diff --git a/go/src/arena/arena.go b/go/src/arena/arena.go
new file mode 100644
index 0000000000000000000000000000000000000000..35b2fbd2aadd8cf69db74a254715afb592e50833
--- /dev/null
+++ b/go/src/arena/arena.go
@@ -0,0 +1,108 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build goexperiment.arenas
+
+/*
+The arena package provides the ability to allocate memory for a collection
+of Go values and free that space manually all at once, safely. The purpose
+of this functionality is to improve efficiency: manually freeing memory
+before a garbage collection delays that cycle. Less frequent cycles means
+the CPU cost of the garbage collector is incurred less frequently.
+
+This functionality in this package is mostly captured in the Arena type.
+Arenas allocate large chunks of memory for Go values, so they're likely to
+be inefficient for allocating only small amounts of small Go values. They're
+best used in bulk, on the order of MiB of memory allocated on each use.
+
+Note that by allowing for this limited form of manual memory allocation
+that use-after-free bugs are possible with regular Go values. This package
+limits the impact of these use-after-free bugs by preventing reuse of freed
+memory regions until the garbage collector is able to determine that it is
+safe. Typically, a use-after-free bug will result in a fault and a helpful
+error message, but this package reserves the right to not force a fault on
+freed memory. That means a valid implementation of this package is to just
+allocate all memory the way the runtime normally would, and in fact, it
+reserves the right to occasionally do so for some Go values.
+*/
+package arena
+
+import (
+ "internal/reflectlite"
+ "unsafe"
+)
+
+// Arena represents a collection of Go values allocated and freed together.
+// Arenas are useful for improving efficiency as they may be freed back to
+// the runtime manually, though any memory obtained from freed arenas must
+// not be accessed once that happens. An Arena is automatically freed once
+// it is no longer referenced, so it must be kept alive (see runtime.KeepAlive)
+// until any memory allocated from it is no longer needed.
+//
+// An Arena must never be used concurrently by multiple goroutines.
+type Arena struct {
+ a unsafe.Pointer
+}
+
+// NewArena allocates a new arena.
+func NewArena() *Arena {
+ return &Arena{a: runtime_arena_newArena()}
+}
+
+// Free frees the arena (and all objects allocated from the arena) so that
+// memory backing the arena can be reused fairly quickly without garbage
+// collection overhead. Applications must not call any method on this
+// arena after it has been freed.
+func (a *Arena) Free() {
+ runtime_arena_arena_Free(a.a)
+ a.a = nil
+}
+
+// New creates a new *T in the provided arena. The *T must not be used after
+// the arena is freed. Accessing the value after free may result in a fault,
+// but this fault is also not guaranteed.
+func New[T any](a *Arena) *T {
+ return runtime_arena_arena_New(a.a, reflectlite.TypeOf((*T)(nil))).(*T)
+}
+
+// MakeSlice creates a new []T with the provided capacity and length. The []T must
+// not be used after the arena is freed. Accessing the underlying storage of the
+// slice after free may result in a fault, but this fault is also not guaranteed.
+func MakeSlice[T any](a *Arena, len, cap int) []T {
+ var sl []T
+ runtime_arena_arena_Slice(a.a, &sl, cap)
+ return sl[:len]
+}
+
+// Clone makes a shallow copy of the input value that is no longer bound to any
+// arena it may have been allocated from, returning the copy. If it was not
+// allocated from an arena, it is returned untouched. This function is useful
+// to more easily let an arena-allocated value out-live its arena.
+// T must be a pointer, a slice, or a string, otherwise this function will panic.
+func Clone[T any](s T) T {
+ return runtime_arena_heapify(s).(T)
+}
+
+//go:linkname reflect_arena_New reflect.arena_New
+func reflect_arena_New(a *Arena, typ any) any {
+ return runtime_arena_arena_New(a.a, typ)
+}
+
+//go:linkname runtime_arena_newArena
+func runtime_arena_newArena() unsafe.Pointer
+
+//go:linkname runtime_arena_arena_New
+func runtime_arena_arena_New(arena unsafe.Pointer, typ any) any
+
+// Mark as noescape to avoid escaping the slice header.
+//
+//go:noescape
+//go:linkname runtime_arena_arena_Slice
+func runtime_arena_arena_Slice(arena unsafe.Pointer, slice any, cap int)
+
+//go:linkname runtime_arena_arena_Free
+func runtime_arena_arena_Free(arena unsafe.Pointer)
+
+//go:linkname runtime_arena_heapify
+func runtime_arena_heapify(any) any
diff --git a/go/src/arena/arena_test.go b/go/src/arena/arena_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..017c33c502a7183c7e64f839ac3b36d0cf82396b
--- /dev/null
+++ b/go/src/arena/arena_test.go
@@ -0,0 +1,42 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build goexperiment.arenas
+
+package arena_test
+
+import (
+ "arena"
+ "testing"
+)
+
+type T1 struct {
+ n int
+}
+type T2 [1 << 20]byte // 1MiB
+
+func TestSmoke(t *testing.T) {
+ a := arena.NewArena()
+ defer a.Free()
+
+ tt := arena.New[T1](a)
+ tt.n = 1
+
+ ts := arena.MakeSlice[T1](a, 99, 100)
+ if len(ts) != 99 {
+ t.Errorf("Slice() len = %d, want 99", len(ts))
+ }
+ if cap(ts) != 100 {
+ t.Errorf("Slice() cap = %d, want 100", cap(ts))
+ }
+ ts[1].n = 42
+}
+
+func TestSmokeLarge(t *testing.T) {
+ a := arena.NewArena()
+ defer a.Free()
+ for i := 0; i < 10*64; i++ {
+ _ = arena.New[T2](a)
+ }
+}
diff --git a/go/src/bufio/bufio.go b/go/src/bufio/bufio.go
new file mode 100644
index 0000000000000000000000000000000000000000..141a9a1a2a2305f070ec7ecf38ca16152ee2aeb9
--- /dev/null
+++ b/go/src/bufio/bufio.go
@@ -0,0 +1,842 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package bufio implements buffered I/O. It wraps an io.Reader or io.Writer
+// object, creating another object (Reader or Writer) that also implements
+// the interface but provides buffering and some help for textual I/O.
+package bufio
+
+import (
+ "bytes"
+ "errors"
+ "io"
+ "strings"
+ "unicode/utf8"
+)
+
+const (
+ defaultBufSize = 4096
+)
+
+var (
+ ErrInvalidUnreadByte = errors.New("bufio: invalid use of UnreadByte")
+ ErrInvalidUnreadRune = errors.New("bufio: invalid use of UnreadRune")
+ ErrBufferFull = errors.New("bufio: buffer full")
+ ErrNegativeCount = errors.New("bufio: negative count")
+)
+
+// Buffered input.
+
+// Reader implements buffering for an io.Reader object.
+// A new Reader is created by calling [NewReader] or [NewReaderSize];
+// alternatively the zero value of a Reader may be used after calling [Reset]
+// on it.
+type Reader struct {
+ buf []byte
+ rd io.Reader // reader provided by the client
+ r, w int // buf read and write positions
+ err error
+ lastByte int // last byte read for UnreadByte; -1 means invalid
+ lastRuneSize int // size of last rune read for UnreadRune; -1 means invalid
+}
+
+const minReadBufferSize = 16
+const maxConsecutiveEmptyReads = 100
+
+// NewReaderSize returns a new [Reader] whose buffer has at least the specified
+// size. If the argument io.Reader is already a [Reader] with large enough
+// size, it returns the underlying [Reader].
+func NewReaderSize(rd io.Reader, size int) *Reader {
+ // Is it already a Reader?
+ b, ok := rd.(*Reader)
+ if ok && len(b.buf) >= size {
+ return b
+ }
+ r := new(Reader)
+ r.reset(make([]byte, max(size, minReadBufferSize)), rd)
+ return r
+}
+
+// NewReader returns a new [Reader] whose buffer has the default size.
+func NewReader(rd io.Reader) *Reader {
+ return NewReaderSize(rd, defaultBufSize)
+}
+
+// Size returns the size of the underlying buffer in bytes.
+func (b *Reader) Size() int { return len(b.buf) }
+
+// Reset discards any buffered data, resets all state, and switches
+// the buffered reader to read from r.
+// Calling Reset on the zero value of [Reader] initializes the internal buffer
+// to the default size.
+// Calling b.Reset(b) (that is, resetting a [Reader] to itself) does nothing.
+func (b *Reader) Reset(r io.Reader) {
+ // If a Reader r is passed to NewReader, NewReader will return r.
+ // Different layers of code may do that, and then later pass r
+ // to Reset. Avoid infinite recursion in that case.
+ if b == r {
+ return
+ }
+ if b.buf == nil {
+ b.buf = make([]byte, defaultBufSize)
+ }
+ b.reset(b.buf, r)
+}
+
+func (b *Reader) reset(buf []byte, r io.Reader) {
+ *b = Reader{
+ buf: buf,
+ rd: r,
+ lastByte: -1,
+ lastRuneSize: -1,
+ }
+}
+
+var errNegativeRead = errors.New("bufio: reader returned negative count from Read")
+
+// fill reads a new chunk into the buffer.
+func (b *Reader) fill() {
+ // Slide existing data to beginning.
+ if b.r > 0 {
+ copy(b.buf, b.buf[b.r:b.w])
+ b.w -= b.r
+ b.r = 0
+ }
+
+ if b.w >= len(b.buf) {
+ panic("bufio: tried to fill full buffer")
+ }
+
+ // Read new data: try a limited number of times.
+ for i := maxConsecutiveEmptyReads; i > 0; i-- {
+ n, err := b.rd.Read(b.buf[b.w:])
+ if n < 0 {
+ panic(errNegativeRead)
+ }
+ b.w += n
+ if err != nil {
+ b.err = err
+ return
+ }
+ if n > 0 {
+ return
+ }
+ }
+ b.err = io.ErrNoProgress
+}
+
+func (b *Reader) readErr() error {
+ err := b.err
+ b.err = nil
+ return err
+}
+
+// Peek returns the next n bytes without advancing the reader. The bytes stop
+// being valid at the next read call. If necessary, Peek will read more bytes
+// into the buffer in order to make n bytes available. If Peek returns fewer
+// than n bytes, it also returns an error explaining why the read is short.
+// The error is [ErrBufferFull] if n is larger than b's buffer size.
+//
+// Calling Peek prevents a [Reader.UnreadByte] or [Reader.UnreadRune] call from succeeding
+// until the next read operation.
+func (b *Reader) Peek(n int) ([]byte, error) {
+ if n < 0 {
+ return nil, ErrNegativeCount
+ }
+
+ b.lastByte = -1
+ b.lastRuneSize = -1
+
+ for b.w-b.r < n && b.w-b.r < len(b.buf) && b.err == nil {
+ b.fill() // b.w-b.r < len(b.buf) => buffer is not full
+ }
+
+ if n > len(b.buf) {
+ return b.buf[b.r:b.w], ErrBufferFull
+ }
+
+ // 0 <= n <= len(b.buf)
+ var err error
+ if avail := b.w - b.r; avail < n {
+ // not enough data in buffer
+ n = avail
+ err = b.readErr()
+ if err == nil {
+ err = ErrBufferFull
+ }
+ }
+ return b.buf[b.r : b.r+n], err
+}
+
+// Discard skips the next n bytes, returning the number of bytes discarded.
+//
+// If Discard skips fewer than n bytes, it also returns an error.
+// If 0 <= n <= b.Buffered(), Discard is guaranteed to succeed without
+// reading from the underlying io.Reader.
+func (b *Reader) Discard(n int) (discarded int, err error) {
+ if n < 0 {
+ return 0, ErrNegativeCount
+ }
+ if n == 0 {
+ return
+ }
+
+ b.lastByte = -1
+ b.lastRuneSize = -1
+
+ remain := n
+ for {
+ skip := b.Buffered()
+ if skip == 0 {
+ b.fill()
+ skip = b.Buffered()
+ }
+ if skip > remain {
+ skip = remain
+ }
+ b.r += skip
+ remain -= skip
+ if remain == 0 {
+ return n, nil
+ }
+ if b.err != nil {
+ return n - remain, b.readErr()
+ }
+ }
+}
+
+// Read reads data into p.
+// It returns the number of bytes read into p.
+// The bytes are taken from at most one Read on the underlying [Reader],
+// hence n may be less than len(p).
+// To read exactly len(p) bytes, use io.ReadFull(b, p).
+// If the underlying [Reader] can return a non-zero count with io.EOF,
+// then this Read method can do so as well; see the [io.Reader] docs.
+func (b *Reader) Read(p []byte) (n int, err error) {
+ n = len(p)
+ if n == 0 {
+ if b.Buffered() > 0 {
+ return 0, nil
+ }
+ return 0, b.readErr()
+ }
+ if b.r == b.w {
+ if b.err != nil {
+ return 0, b.readErr()
+ }
+ if len(p) >= len(b.buf) {
+ // Large read, empty buffer.
+ // Read directly into p to avoid copy.
+ n, b.err = b.rd.Read(p)
+ if n < 0 {
+ panic(errNegativeRead)
+ }
+ if n > 0 {
+ b.lastByte = int(p[n-1])
+ b.lastRuneSize = -1
+ }
+ return n, b.readErr()
+ }
+ // One read.
+ // Do not use b.fill, which will loop.
+ b.r = 0
+ b.w = 0
+ n, b.err = b.rd.Read(b.buf)
+ if n < 0 {
+ panic(errNegativeRead)
+ }
+ if n == 0 {
+ return 0, b.readErr()
+ }
+ b.w += n
+ }
+
+ // copy as much as we can
+ // Note: if the slice panics here, it is probably because
+ // the underlying reader returned a bad count. See issue 49795.
+ n = copy(p, b.buf[b.r:b.w])
+ b.r += n
+ b.lastByte = int(b.buf[b.r-1])
+ b.lastRuneSize = -1
+ return n, nil
+}
+
+// ReadByte reads and returns a single byte.
+// If no byte is available, returns an error.
+func (b *Reader) ReadByte() (byte, error) {
+ b.lastRuneSize = -1
+ for b.r == b.w {
+ if b.err != nil {
+ return 0, b.readErr()
+ }
+ b.fill() // buffer is empty
+ }
+ c := b.buf[b.r]
+ b.r++
+ b.lastByte = int(c)
+ return c, nil
+}
+
+// UnreadByte unreads the last byte. Only the most recently read byte can be unread.
+//
+// UnreadByte returns an error if the most recent method called on the
+// [Reader] was not a read operation. Notably, [Reader.Peek], [Reader.Discard], and [Reader.WriteTo] are not
+// considered read operations.
+func (b *Reader) UnreadByte() error {
+ if b.lastByte < 0 || b.r == 0 && b.w > 0 {
+ return ErrInvalidUnreadByte
+ }
+ // b.r > 0 || b.w == 0
+ if b.r > 0 {
+ b.r--
+ } else {
+ // b.r == 0 && b.w == 0
+ b.w = 1
+ }
+ b.buf[b.r] = byte(b.lastByte)
+ b.lastByte = -1
+ b.lastRuneSize = -1
+ return nil
+}
+
+// ReadRune reads a single UTF-8 encoded Unicode character and returns the
+// rune and its size in bytes. If the encoded rune is invalid, it consumes one byte
+// and returns unicode.ReplacementChar (U+FFFD) with a size of 1.
+func (b *Reader) ReadRune() (r rune, size int, err error) {
+ for b.r+utf8.UTFMax > b.w && !utf8.FullRune(b.buf[b.r:b.w]) && b.err == nil && b.w-b.r < len(b.buf) {
+ b.fill() // b.w-b.r < len(buf) => buffer is not full
+ }
+ b.lastRuneSize = -1
+ if b.r == b.w {
+ return 0, 0, b.readErr()
+ }
+ r, size = utf8.DecodeRune(b.buf[b.r:b.w])
+ b.r += size
+ b.lastByte = int(b.buf[b.r-1])
+ b.lastRuneSize = size
+ return r, size, nil
+}
+
+// UnreadRune unreads the last rune. If the most recent method called on
+// the [Reader] was not a [Reader.ReadRune], [Reader.UnreadRune] returns an error. (In this
+// regard it is stricter than [Reader.UnreadByte], which will unread the last byte
+// from any read operation.)
+func (b *Reader) UnreadRune() error {
+ if b.lastRuneSize < 0 || b.r < b.lastRuneSize {
+ return ErrInvalidUnreadRune
+ }
+ b.r -= b.lastRuneSize
+ b.lastByte = -1
+ b.lastRuneSize = -1
+ return nil
+}
+
+// Buffered returns the number of bytes that can be read from the current buffer.
+func (b *Reader) Buffered() int { return b.w - b.r }
+
+// ReadSlice reads until the first occurrence of delim in the input,
+// returning a slice pointing at the bytes in the buffer.
+// The bytes stop being valid at the next read.
+// If ReadSlice encounters an error before finding a delimiter,
+// it returns all the data in the buffer and the error itself (often io.EOF).
+// ReadSlice fails with error [ErrBufferFull] if the buffer fills without a delim.
+// Because the data returned from ReadSlice will be overwritten
+// by the next I/O operation, most clients should use
+// [Reader.ReadBytes] or ReadString instead.
+// ReadSlice returns err != nil if and only if line does not end in delim.
+func (b *Reader) ReadSlice(delim byte) (line []byte, err error) {
+ s := 0 // search start index
+ for {
+ // Search buffer.
+ if i := bytes.IndexByte(b.buf[b.r+s:b.w], delim); i >= 0 {
+ i += s
+ line = b.buf[b.r : b.r+i+1]
+ b.r += i + 1
+ break
+ }
+
+ // Pending error?
+ if b.err != nil {
+ line = b.buf[b.r:b.w]
+ b.r = b.w
+ err = b.readErr()
+ break
+ }
+
+ // Buffer full?
+ if b.Buffered() >= len(b.buf) {
+ b.r = b.w
+ line = b.buf
+ err = ErrBufferFull
+ break
+ }
+
+ s = b.w - b.r // do not rescan area we scanned before
+
+ b.fill() // buffer is not full
+ }
+
+ // Handle last byte, if any.
+ if i := len(line) - 1; i >= 0 {
+ b.lastByte = int(line[i])
+ b.lastRuneSize = -1
+ }
+
+ return
+}
+
+// ReadLine is a low-level line-reading primitive. Most callers should use
+// [Reader.ReadBytes]('\n') or [Reader.ReadString]('\n') instead or use a [Scanner].
+//
+// ReadLine tries to return a single line, not including the end-of-line bytes.
+// If the line was too long for the buffer then isPrefix is set and the
+// beginning of the line is returned. The rest of the line will be returned
+// from future calls. isPrefix will be false when returning the last fragment
+// of the line. The returned buffer is only valid until the next call to
+// ReadLine. ReadLine either returns a non-nil line or it returns an error,
+// never both.
+//
+// The text returned from ReadLine does not include the line end ("\r\n" or "\n").
+// No indication or error is given if the input ends without a final line end.
+// Calling [Reader.UnreadByte] after ReadLine will always unread the last byte read
+// (possibly a character belonging to the line end) even if that byte is not
+// part of the line returned by ReadLine.
+func (b *Reader) ReadLine() (line []byte, isPrefix bool, err error) {
+ line, err = b.ReadSlice('\n')
+ if err == ErrBufferFull {
+ // Handle the case where "\r\n" straddles the buffer.
+ if len(line) > 0 && line[len(line)-1] == '\r' {
+ // Put the '\r' back on buf and drop it from line.
+ // Let the next call to ReadLine check for "\r\n".
+ if b.r == 0 {
+ // should be unreachable
+ panic("bufio: tried to rewind past start of buffer")
+ }
+ b.r--
+ line = line[:len(line)-1]
+ }
+ return line, true, nil
+ }
+
+ if len(line) == 0 {
+ if err != nil {
+ line = nil
+ }
+ return
+ }
+ err = nil
+
+ if line[len(line)-1] == '\n' {
+ drop := 1
+ if len(line) > 1 && line[len(line)-2] == '\r' {
+ drop = 2
+ }
+ line = line[:len(line)-drop]
+ }
+ return
+}
+
+// collectFragments reads until the first occurrence of delim in the input. It
+// returns (slice of full buffers, remaining bytes before delim, total number
+// of bytes in the combined first two elements, error).
+// The complete result is equal to
+// `bytes.Join(append(fullBuffers, finalFragment), nil)`, which has a
+// length of `totalLen`. The result is structured in this way to allow callers
+// to minimize allocations and copies.
+func (b *Reader) collectFragments(delim byte) (fullBuffers [][]byte, finalFragment []byte, totalLen int, err error) {
+ var frag []byte
+ // Use ReadSlice to look for delim, accumulating full buffers.
+ for {
+ var e error
+ frag, e = b.ReadSlice(delim)
+ if e == nil { // got final fragment
+ break
+ }
+ if e != ErrBufferFull { // unexpected error
+ err = e
+ break
+ }
+
+ // Make a copy of the buffer.
+ buf := bytes.Clone(frag)
+ fullBuffers = append(fullBuffers, buf)
+ totalLen += len(buf)
+ }
+
+ totalLen += len(frag)
+ return fullBuffers, frag, totalLen, err
+}
+
+// ReadBytes reads until the first occurrence of delim in the input,
+// returning a slice containing the data up to and including the delimiter.
+// If ReadBytes encounters an error before finding a delimiter,
+// it returns the data read before the error and the error itself (often io.EOF).
+// ReadBytes returns err != nil if and only if the returned data does not end in
+// delim.
+// For simple uses, a Scanner may be more convenient.
+func (b *Reader) ReadBytes(delim byte) ([]byte, error) {
+ full, frag, n, err := b.collectFragments(delim)
+ // Allocate new buffer to hold the full pieces and the fragment.
+ buf := make([]byte, n)
+ n = 0
+ // Copy full pieces and fragment in.
+ for i := range full {
+ n += copy(buf[n:], full[i])
+ }
+ copy(buf[n:], frag)
+ return buf, err
+}
+
+// ReadString reads until the first occurrence of delim in the input,
+// returning a string containing the data up to and including the delimiter.
+// If ReadString encounters an error before finding a delimiter,
+// it returns the data read before the error and the error itself (often io.EOF).
+// ReadString returns err != nil if and only if the returned data does not end in
+// delim.
+// For simple uses, a Scanner may be more convenient.
+func (b *Reader) ReadString(delim byte) (string, error) {
+ full, frag, n, err := b.collectFragments(delim)
+ // Allocate new buffer to hold the full pieces and the fragment.
+ var buf strings.Builder
+ buf.Grow(n)
+ // Copy full pieces and fragment in.
+ for _, fb := range full {
+ buf.Write(fb)
+ }
+ buf.Write(frag)
+ return buf.String(), err
+}
+
+// WriteTo implements io.WriterTo.
+// This may make multiple calls to the [Reader.Read] method of the underlying [Reader].
+// If the underlying reader supports the [Reader.WriteTo] method,
+// this calls the underlying [Reader.WriteTo] without buffering.
+func (b *Reader) WriteTo(w io.Writer) (n int64, err error) {
+ b.lastByte = -1
+ b.lastRuneSize = -1
+
+ if b.r < b.w {
+ n, err = b.writeBuf(w)
+ if err != nil {
+ return
+ }
+ }
+
+ if r, ok := b.rd.(io.WriterTo); ok {
+ m, err := r.WriteTo(w)
+ n += m
+ return n, err
+ }
+
+ if w, ok := w.(io.ReaderFrom); ok {
+ m, err := w.ReadFrom(b.rd)
+ n += m
+ return n, err
+ }
+
+ if b.w-b.r < len(b.buf) {
+ b.fill() // buffer not full
+ }
+
+ for b.r < b.w {
+ // b.r < b.w => buffer is not empty
+ m, err := b.writeBuf(w)
+ n += m
+ if err != nil {
+ return n, err
+ }
+ b.fill() // buffer is empty
+ }
+
+ if b.err == io.EOF {
+ b.err = nil
+ }
+
+ return n, b.readErr()
+}
+
+var errNegativeWrite = errors.New("bufio: writer returned negative count from Write")
+
+// writeBuf writes the [Reader]'s buffer to the writer.
+func (b *Reader) writeBuf(w io.Writer) (int64, error) {
+ n, err := w.Write(b.buf[b.r:b.w])
+ if n < 0 {
+ panic(errNegativeWrite)
+ }
+ b.r += n
+ return int64(n), err
+}
+
+// buffered output
+
+// Writer implements buffering for an [io.Writer] object.
+// If an error occurs writing to a [Writer], no more data will be
+// accepted and all subsequent writes, and [Writer.Flush], will return the error.
+// After all data has been written, the client should call the
+// [Writer.Flush] method to guarantee all data has been forwarded to
+// the underlying [io.Writer].
+type Writer struct {
+ err error
+ buf []byte
+ n int
+ wr io.Writer
+}
+
+// NewWriterSize returns a new [Writer] whose buffer has at least the specified
+// size. If the argument io.Writer is already a [Writer] with large enough
+// size, it returns the underlying [Writer].
+func NewWriterSize(w io.Writer, size int) *Writer {
+ // Is it already a Writer?
+ b, ok := w.(*Writer)
+ if ok && len(b.buf) >= size {
+ return b
+ }
+ if size <= 0 {
+ size = defaultBufSize
+ }
+ return &Writer{
+ buf: make([]byte, size),
+ wr: w,
+ }
+}
+
+// NewWriter returns a new [Writer] whose buffer has the default size.
+// If the argument io.Writer is already a [Writer] with large enough buffer size,
+// it returns the underlying [Writer].
+func NewWriter(w io.Writer) *Writer {
+ return NewWriterSize(w, defaultBufSize)
+}
+
+// Size returns the size of the underlying buffer in bytes.
+func (b *Writer) Size() int { return len(b.buf) }
+
+// Reset discards any unflushed buffered data, clears any error, and
+// resets b to write its output to w.
+// Calling Reset on the zero value of [Writer] initializes the internal buffer
+// to the default size.
+// Calling w.Reset(w) (that is, resetting a [Writer] to itself) does nothing.
+func (b *Writer) Reset(w io.Writer) {
+ // If a Writer w is passed to NewWriter, NewWriter will return w.
+ // Different layers of code may do that, and then later pass w
+ // to Reset. Avoid infinite recursion in that case.
+ if b == w {
+ return
+ }
+ if b.buf == nil {
+ b.buf = make([]byte, defaultBufSize)
+ }
+ b.err = nil
+ b.n = 0
+ b.wr = w
+}
+
+// Flush writes any buffered data to the underlying [io.Writer].
+func (b *Writer) Flush() error {
+ if b.err != nil {
+ return b.err
+ }
+ if b.n == 0 {
+ return nil
+ }
+ n, err := b.wr.Write(b.buf[0:b.n])
+ if n < b.n && err == nil {
+ err = io.ErrShortWrite
+ }
+ if err != nil {
+ if n > 0 && n < b.n {
+ copy(b.buf[0:b.n-n], b.buf[n:b.n])
+ }
+ b.n -= n
+ b.err = err
+ return err
+ }
+ b.n = 0
+ return nil
+}
+
+// Available returns how many bytes are unused in the buffer.
+func (b *Writer) Available() int { return len(b.buf) - b.n }
+
+// AvailableBuffer returns an empty buffer with b.Available() capacity.
+// This buffer is intended to be appended to and
+// passed to an immediately succeeding [Writer.Write] call.
+// The buffer is only valid until the next write operation on b.
+func (b *Writer) AvailableBuffer() []byte {
+ return b.buf[b.n:][:0]
+}
+
+// Buffered returns the number of bytes that have been written into the current buffer.
+func (b *Writer) Buffered() int { return b.n }
+
+// Write writes the contents of p into the buffer.
+// It returns the number of bytes written.
+// If nn < len(p), it also returns an error explaining
+// why the write is short.
+func (b *Writer) Write(p []byte) (nn int, err error) {
+ for len(p) > b.Available() && b.err == nil {
+ var n int
+ if b.Buffered() == 0 {
+ // Large write, empty buffer.
+ // Write directly from p to avoid copy.
+ n, b.err = b.wr.Write(p)
+ } else {
+ n = copy(b.buf[b.n:], p)
+ b.n += n
+ b.Flush()
+ }
+ nn += n
+ p = p[n:]
+ }
+ if b.err != nil {
+ return nn, b.err
+ }
+ n := copy(b.buf[b.n:], p)
+ b.n += n
+ nn += n
+ return nn, nil
+}
+
+// WriteByte writes a single byte.
+func (b *Writer) WriteByte(c byte) error {
+ if b.err != nil {
+ return b.err
+ }
+ if b.Available() <= 0 && b.Flush() != nil {
+ return b.err
+ }
+ b.buf[b.n] = c
+ b.n++
+ return nil
+}
+
+// WriteRune writes a single Unicode code point, returning
+// the number of bytes written and any error.
+func (b *Writer) WriteRune(r rune) (size int, err error) {
+ // Compare as uint32 to correctly handle negative runes.
+ if uint32(r) < utf8.RuneSelf {
+ err = b.WriteByte(byte(r))
+ if err != nil {
+ return 0, err
+ }
+ return 1, nil
+ }
+ if b.err != nil {
+ return 0, b.err
+ }
+ n := b.Available()
+ if n < utf8.UTFMax {
+ if b.Flush(); b.err != nil {
+ return 0, b.err
+ }
+ n = b.Available()
+ if n < utf8.UTFMax {
+ // Can only happen if buffer is silly small.
+ return b.WriteString(string(r))
+ }
+ }
+ size = utf8.EncodeRune(b.buf[b.n:], r)
+ b.n += size
+ return size, nil
+}
+
+// WriteString writes a string.
+// It returns the number of bytes written.
+// If the count is less than len(s), it also returns an error explaining
+// why the write is short.
+func (b *Writer) WriteString(s string) (int, error) {
+ var sw io.StringWriter
+ tryStringWriter := true
+
+ nn := 0
+ for len(s) > b.Available() && b.err == nil {
+ var n int
+ if b.Buffered() == 0 && sw == nil && tryStringWriter {
+ // Check at most once whether b.wr is a StringWriter.
+ sw, tryStringWriter = b.wr.(io.StringWriter)
+ }
+ if b.Buffered() == 0 && tryStringWriter {
+ // Large write, empty buffer, and the underlying writer supports
+ // WriteString: forward the write to the underlying StringWriter.
+ // This avoids an extra copy.
+ n, b.err = sw.WriteString(s)
+ } else {
+ n = copy(b.buf[b.n:], s)
+ b.n += n
+ b.Flush()
+ }
+ nn += n
+ s = s[n:]
+ }
+ if b.err != nil {
+ return nn, b.err
+ }
+ n := copy(b.buf[b.n:], s)
+ b.n += n
+ nn += n
+ return nn, nil
+}
+
+// ReadFrom implements [io.ReaderFrom]. If the underlying writer
+// supports the ReadFrom method, this calls the underlying ReadFrom.
+// If there is buffered data and an underlying ReadFrom, this fills
+// the buffer and writes it before calling ReadFrom.
+func (b *Writer) ReadFrom(r io.Reader) (n int64, err error) {
+ if b.err != nil {
+ return 0, b.err
+ }
+ readerFrom, readerFromOK := b.wr.(io.ReaderFrom)
+ var m int
+ for {
+ if b.Available() == 0 {
+ if err1 := b.Flush(); err1 != nil {
+ return n, err1
+ }
+ }
+ if readerFromOK && b.Buffered() == 0 {
+ nn, err := readerFrom.ReadFrom(r)
+ b.err = err
+ n += nn
+ return n, err
+ }
+ nr := 0
+ for nr < maxConsecutiveEmptyReads {
+ m, err = r.Read(b.buf[b.n:])
+ if m != 0 || err != nil {
+ break
+ }
+ nr++
+ }
+ if nr == maxConsecutiveEmptyReads {
+ return n, io.ErrNoProgress
+ }
+ b.n += m
+ n += int64(m)
+ if err != nil {
+ break
+ }
+ }
+ if err == io.EOF {
+ // If we filled the buffer exactly, flush preemptively.
+ if b.Available() == 0 {
+ err = b.Flush()
+ } else {
+ err = nil
+ }
+ }
+ return n, err
+}
+
+// buffered input and output
+
+// ReadWriter stores pointers to a [Reader] and a [Writer].
+// It implements [io.ReadWriter].
+type ReadWriter struct {
+ *Reader
+ *Writer
+}
+
+// NewReadWriter allocates a new [ReadWriter] that dispatches to r and w.
+func NewReadWriter(r *Reader, w *Writer) *ReadWriter {
+ return &ReadWriter{r, w}
+}
diff --git a/go/src/bufio/bufio_test.go b/go/src/bufio/bufio_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..742e195425690332dcf32487df3834e04a4a38ea
--- /dev/null
+++ b/go/src/bufio/bufio_test.go
@@ -0,0 +1,1999 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bufio_test
+
+import (
+ . "bufio"
+ "bytes"
+ "errors"
+ "fmt"
+ "internal/asan"
+ "io"
+ "math/rand"
+ "strconv"
+ "strings"
+ "testing"
+ "testing/iotest"
+ "time"
+ "unicode/utf8"
+)
+
+// Reads from a reader and rot13s the result.
+type rot13Reader struct {
+ r io.Reader
+}
+
+func newRot13Reader(r io.Reader) *rot13Reader {
+ r13 := new(rot13Reader)
+ r13.r = r
+ return r13
+}
+
+func (r13 *rot13Reader) Read(p []byte) (int, error) {
+ n, err := r13.r.Read(p)
+ for i := 0; i < n; i++ {
+ c := p[i] | 0x20 // lowercase byte
+ if 'a' <= c && c <= 'm' {
+ p[i] += 13
+ } else if 'n' <= c && c <= 'z' {
+ p[i] -= 13
+ }
+ }
+ return n, err
+}
+
+// Call ReadByte to accumulate the text of a file
+func readBytes(buf *Reader) string {
+ var b [1000]byte
+ nb := 0
+ for {
+ c, err := buf.ReadByte()
+ if err == io.EOF {
+ break
+ }
+ if err == nil {
+ b[nb] = c
+ nb++
+ } else if err != iotest.ErrTimeout {
+ panic("Data: " + err.Error())
+ }
+ }
+ return string(b[0:nb])
+}
+
+func TestReaderSimple(t *testing.T) {
+ data := "hello world"
+ b := NewReader(strings.NewReader(data))
+ if s := readBytes(b); s != "hello world" {
+ t.Errorf("simple hello world test failed: got %q", s)
+ }
+
+ b = NewReader(newRot13Reader(strings.NewReader(data)))
+ if s := readBytes(b); s != "uryyb jbeyq" {
+ t.Errorf("rot13 hello world test failed: got %q", s)
+ }
+}
+
+type readMaker struct {
+ name string
+ fn func(io.Reader) io.Reader
+}
+
+var readMakers = []readMaker{
+ {"full", func(r io.Reader) io.Reader { return r }},
+ {"byte", iotest.OneByteReader},
+ {"half", iotest.HalfReader},
+ {"data+err", iotest.DataErrReader},
+ {"timeout", iotest.TimeoutReader},
+}
+
+// Call ReadString (which ends up calling everything else)
+// to accumulate the text of a file.
+func readLines(b *Reader) string {
+ s := ""
+ for {
+ s1, err := b.ReadString('\n')
+ if err == io.EOF {
+ break
+ }
+ if err != nil && err != iotest.ErrTimeout {
+ panic("GetLines: " + err.Error())
+ }
+ s += s1
+ }
+ return s
+}
+
+// Call Read to accumulate the text of a file
+func reads(buf *Reader, m int) string {
+ var b [1000]byte
+ nb := 0
+ for {
+ n, err := buf.Read(b[nb : nb+m])
+ nb += n
+ if err == io.EOF {
+ break
+ }
+ }
+ return string(b[0:nb])
+}
+
+type bufReader struct {
+ name string
+ fn func(*Reader) string
+}
+
+var bufreaders = []bufReader{
+ {"1", func(b *Reader) string { return reads(b, 1) }},
+ {"2", func(b *Reader) string { return reads(b, 2) }},
+ {"3", func(b *Reader) string { return reads(b, 3) }},
+ {"4", func(b *Reader) string { return reads(b, 4) }},
+ {"5", func(b *Reader) string { return reads(b, 5) }},
+ {"7", func(b *Reader) string { return reads(b, 7) }},
+ {"bytes", readBytes},
+ {"lines", readLines},
+}
+
+const minReadBufferSize = 16
+
+var bufsizes = []int{
+ 0, minReadBufferSize, 23, 32, 46, 64, 93, 128, 1024, 4096,
+}
+
+func TestReader(t *testing.T) {
+ var texts [31]string
+ str := ""
+ all := ""
+ for i := 0; i < len(texts)-1; i++ {
+ texts[i] = str + "\n"
+ all += texts[i]
+ str += string(rune(i%26 + 'a'))
+ }
+ texts[len(texts)-1] = all
+
+ for h := 0; h < len(texts); h++ {
+ text := texts[h]
+ for i := 0; i < len(readMakers); i++ {
+ for j := 0; j < len(bufreaders); j++ {
+ for k := 0; k < len(bufsizes); k++ {
+ readmaker := readMakers[i]
+ bufreader := bufreaders[j]
+ bufsize := bufsizes[k]
+ read := readmaker.fn(strings.NewReader(text))
+ buf := NewReaderSize(read, bufsize)
+ s := bufreader.fn(buf)
+ if s != text {
+ t.Errorf("reader=%s fn=%s bufsize=%d want=%q got=%q",
+ readmaker.name, bufreader.name, bufsize, text, s)
+ }
+ }
+ }
+ }
+ }
+}
+
+type zeroReader struct{}
+
+func (zeroReader) Read(p []byte) (int, error) {
+ return 0, nil
+}
+
+func TestZeroReader(t *testing.T) {
+ var z zeroReader
+ r := NewReader(z)
+
+ c := make(chan error)
+ go func() {
+ _, err := r.ReadByte()
+ c <- err
+ }()
+
+ select {
+ case err := <-c:
+ if err == nil {
+ t.Error("error expected")
+ } else if err != io.ErrNoProgress {
+ t.Error("unexpected error:", err)
+ }
+ case <-time.After(time.Second):
+ t.Error("test timed out (endless loop in ReadByte?)")
+ }
+}
+
+// A StringReader delivers its data one string segment at a time via Read.
+type StringReader struct {
+ data []string
+ step int
+}
+
+func (r *StringReader) Read(p []byte) (n int, err error) {
+ if r.step < len(r.data) {
+ s := r.data[r.step]
+ n = copy(p, s)
+ r.step++
+ } else {
+ err = io.EOF
+ }
+ return
+}
+
+func readRuneSegments(t *testing.T, segments []string) {
+ got := ""
+ want := strings.Join(segments, "")
+ r := NewReader(&StringReader{data: segments})
+ for {
+ r, _, err := r.ReadRune()
+ if err != nil {
+ if err != io.EOF {
+ return
+ }
+ break
+ }
+ got += string(r)
+ }
+ if got != want {
+ t.Errorf("segments=%v got=%s want=%s", segments, got, want)
+ }
+}
+
+var segmentList = [][]string{
+ {},
+ {""},
+ {"日", "本語"},
+ {"\u65e5", "\u672c", "\u8a9e"},
+ {"\U000065e5", "\U0000672c", "\U00008a9e"},
+ {"\xe6", "\x97\xa5\xe6", "\x9c\xac\xe8\xaa\x9e"},
+ {"Hello", ", ", "World", "!"},
+ {"Hello", ", ", "", "World", "!"},
+}
+
+func TestReadRune(t *testing.T) {
+ for _, s := range segmentList {
+ readRuneSegments(t, s)
+ }
+}
+
+func TestUnreadRune(t *testing.T) {
+ segments := []string{"Hello, world:", "日本語"}
+ r := NewReader(&StringReader{data: segments})
+ got := ""
+ want := strings.Join(segments, "")
+ // Normal execution.
+ for {
+ r1, _, err := r.ReadRune()
+ if err != nil {
+ if err != io.EOF {
+ t.Error("unexpected error on ReadRune:", err)
+ }
+ break
+ }
+ got += string(r1)
+ // Put it back and read it again.
+ if err = r.UnreadRune(); err != nil {
+ t.Fatal("unexpected error on UnreadRune:", err)
+ }
+ r2, _, err := r.ReadRune()
+ if err != nil {
+ t.Fatal("unexpected error reading after unreading:", err)
+ }
+ if r1 != r2 {
+ t.Fatalf("incorrect rune after unread: got %c, want %c", r1, r2)
+ }
+ }
+ if got != want {
+ t.Errorf("got %q, want %q", got, want)
+ }
+}
+
+func TestNoUnreadRuneAfterPeek(t *testing.T) {
+ br := NewReader(strings.NewReader("example"))
+ br.ReadRune()
+ br.Peek(1)
+ if err := br.UnreadRune(); err == nil {
+ t.Error("UnreadRune didn't fail after Peek")
+ }
+}
+
+func TestNoUnreadByteAfterPeek(t *testing.T) {
+ br := NewReader(strings.NewReader("example"))
+ br.ReadByte()
+ br.Peek(1)
+ if err := br.UnreadByte(); err == nil {
+ t.Error("UnreadByte didn't fail after Peek")
+ }
+}
+
+func TestNoUnreadRuneAfterDiscard(t *testing.T) {
+ br := NewReader(strings.NewReader("example"))
+ br.ReadRune()
+ br.Discard(1)
+ if err := br.UnreadRune(); err == nil {
+ t.Error("UnreadRune didn't fail after Discard")
+ }
+}
+
+func TestNoUnreadByteAfterDiscard(t *testing.T) {
+ br := NewReader(strings.NewReader("example"))
+ br.ReadByte()
+ br.Discard(1)
+ if err := br.UnreadByte(); err == nil {
+ t.Error("UnreadByte didn't fail after Discard")
+ }
+}
+
+func TestNoUnreadRuneAfterWriteTo(t *testing.T) {
+ br := NewReader(strings.NewReader("example"))
+ br.WriteTo(io.Discard)
+ if err := br.UnreadRune(); err == nil {
+ t.Error("UnreadRune didn't fail after WriteTo")
+ }
+}
+
+func TestNoUnreadByteAfterWriteTo(t *testing.T) {
+ br := NewReader(strings.NewReader("example"))
+ br.WriteTo(io.Discard)
+ if err := br.UnreadByte(); err == nil {
+ t.Error("UnreadByte didn't fail after WriteTo")
+ }
+}
+
+func TestUnreadByte(t *testing.T) {
+ segments := []string{"Hello, ", "world"}
+ r := NewReader(&StringReader{data: segments})
+ got := ""
+ want := strings.Join(segments, "")
+ // Normal execution.
+ for {
+ b1, err := r.ReadByte()
+ if err != nil {
+ if err != io.EOF {
+ t.Error("unexpected error on ReadByte:", err)
+ }
+ break
+ }
+ got += string(b1)
+ // Put it back and read it again.
+ if err = r.UnreadByte(); err != nil {
+ t.Fatal("unexpected error on UnreadByte:", err)
+ }
+ b2, err := r.ReadByte()
+ if err != nil {
+ t.Fatal("unexpected error reading after unreading:", err)
+ }
+ if b1 != b2 {
+ t.Fatalf("incorrect byte after unread: got %q, want %q", b1, b2)
+ }
+ }
+ if got != want {
+ t.Errorf("got %q, want %q", got, want)
+ }
+}
+
+func TestUnreadByteMultiple(t *testing.T) {
+ segments := []string{"Hello, ", "world"}
+ data := strings.Join(segments, "")
+ for n := 0; n <= len(data); n++ {
+ r := NewReader(&StringReader{data: segments})
+ // Read n bytes.
+ for i := 0; i < n; i++ {
+ b, err := r.ReadByte()
+ if err != nil {
+ t.Fatalf("n = %d: unexpected error on ReadByte: %v", n, err)
+ }
+ if b != data[i] {
+ t.Fatalf("n = %d: incorrect byte returned from ReadByte: got %q, want %q", n, b, data[i])
+ }
+ }
+ // Unread one byte if there is one.
+ if n > 0 {
+ if err := r.UnreadByte(); err != nil {
+ t.Errorf("n = %d: unexpected error on UnreadByte: %v", n, err)
+ }
+ }
+ // Test that we cannot unread any further.
+ if err := r.UnreadByte(); err == nil {
+ t.Errorf("n = %d: expected error on UnreadByte", n)
+ }
+ }
+}
+
+func TestUnreadByteOthers(t *testing.T) {
+ // A list of readers to use in conjunction with UnreadByte.
+ var readers = []func(*Reader, byte) ([]byte, error){
+ (*Reader).ReadBytes,
+ (*Reader).ReadSlice,
+ func(r *Reader, delim byte) ([]byte, error) {
+ data, err := r.ReadString(delim)
+ return []byte(data), err
+ },
+ // ReadLine doesn't fit the data/pattern easily
+ // so we leave it out. It should be covered via
+ // the ReadSlice test since ReadLine simply calls
+ // ReadSlice, and it's that function that handles
+ // the last byte.
+ }
+
+ // Try all readers with UnreadByte.
+ for rno, read := range readers {
+ // Some input data that is longer than the minimum reader buffer size.
+ const n = 10
+ var buf bytes.Buffer
+ for i := 0; i < n; i++ {
+ buf.WriteString("abcdefg")
+ }
+
+ r := NewReaderSize(&buf, minReadBufferSize)
+ readTo := func(delim byte, want string) {
+ data, err := read(r, delim)
+ if err != nil {
+ t.Fatalf("#%d: unexpected error reading to %c: %v", rno, delim, err)
+ }
+ if got := string(data); got != want {
+ t.Fatalf("#%d: got %q, want %q", rno, got, want)
+ }
+ }
+
+ // Read the data with occasional UnreadByte calls.
+ for i := 0; i < n; i++ {
+ readTo('d', "abcd")
+ for j := 0; j < 3; j++ {
+ if err := r.UnreadByte(); err != nil {
+ t.Fatalf("#%d: unexpected error on UnreadByte: %v", rno, err)
+ }
+ readTo('d', "d")
+ }
+ readTo('g', "efg")
+ }
+
+ // All data should have been read.
+ _, err := r.ReadByte()
+ if err != io.EOF {
+ t.Errorf("#%d: got error %v; want EOF", rno, err)
+ }
+ }
+}
+
+// Test that UnreadRune fails if the preceding operation was not a ReadRune.
+func TestUnreadRuneError(t *testing.T) {
+ buf := make([]byte, 3) // All runes in this test are 3 bytes long
+ r := NewReader(&StringReader{data: []string{"日本語日本語日本語"}})
+ if r.UnreadRune() == nil {
+ t.Error("expected error on UnreadRune from fresh buffer")
+ }
+ _, _, err := r.ReadRune()
+ if err != nil {
+ t.Error("unexpected error on ReadRune (1):", err)
+ }
+ if err = r.UnreadRune(); err != nil {
+ t.Error("unexpected error on UnreadRune (1):", err)
+ }
+ if r.UnreadRune() == nil {
+ t.Error("expected error after UnreadRune (1)")
+ }
+ // Test error after Read.
+ _, _, err = r.ReadRune() // reset state
+ if err != nil {
+ t.Error("unexpected error on ReadRune (2):", err)
+ }
+ _, err = r.Read(buf)
+ if err != nil {
+ t.Error("unexpected error on Read (2):", err)
+ }
+ if r.UnreadRune() == nil {
+ t.Error("expected error after Read (2)")
+ }
+ // Test error after ReadByte.
+ _, _, err = r.ReadRune() // reset state
+ if err != nil {
+ t.Error("unexpected error on ReadRune (2):", err)
+ }
+ for range buf {
+ _, err = r.ReadByte()
+ if err != nil {
+ t.Error("unexpected error on ReadByte (2):", err)
+ }
+ }
+ if r.UnreadRune() == nil {
+ t.Error("expected error after ReadByte")
+ }
+ // Test error after UnreadByte.
+ _, _, err = r.ReadRune() // reset state
+ if err != nil {
+ t.Error("unexpected error on ReadRune (3):", err)
+ }
+ _, err = r.ReadByte()
+ if err != nil {
+ t.Error("unexpected error on ReadByte (3):", err)
+ }
+ err = r.UnreadByte()
+ if err != nil {
+ t.Error("unexpected error on UnreadByte (3):", err)
+ }
+ if r.UnreadRune() == nil {
+ t.Error("expected error after UnreadByte (3)")
+ }
+ // Test error after ReadSlice.
+ _, _, err = r.ReadRune() // reset state
+ if err != nil {
+ t.Error("unexpected error on ReadRune (4):", err)
+ }
+ _, err = r.ReadSlice(0)
+ if err != io.EOF {
+ t.Error("unexpected error on ReadSlice (4):", err)
+ }
+ if r.UnreadRune() == nil {
+ t.Error("expected error after ReadSlice (4)")
+ }
+}
+
+func TestUnreadRuneAtEOF(t *testing.T) {
+ // UnreadRune/ReadRune should error at EOF (was a bug; used to panic)
+ r := NewReader(strings.NewReader("x"))
+ r.ReadRune()
+ r.ReadRune()
+ r.UnreadRune()
+ _, _, err := r.ReadRune()
+ if err == nil {
+ t.Error("expected error at EOF")
+ } else if err != io.EOF {
+ t.Error("expected EOF; got", err)
+ }
+}
+
+func TestReadWriteRune(t *testing.T) {
+ const NRune = 1000
+ byteBuf := new(bytes.Buffer)
+ w := NewWriter(byteBuf)
+ // Write the runes out using WriteRune
+ buf := make([]byte, utf8.UTFMax)
+ for r := rune(0); r < NRune; r++ {
+ size := utf8.EncodeRune(buf, r)
+ nbytes, err := w.WriteRune(r)
+ if err != nil {
+ t.Fatalf("WriteRune(0x%x) error: %s", r, err)
+ }
+ if nbytes != size {
+ t.Fatalf("WriteRune(0x%x) expected %d, got %d", r, size, nbytes)
+ }
+ }
+ w.Flush()
+
+ r := NewReader(byteBuf)
+ // Read them back with ReadRune
+ for r1 := rune(0); r1 < NRune; r1++ {
+ size := utf8.EncodeRune(buf, r1)
+ nr, nbytes, err := r.ReadRune()
+ if nr != r1 || nbytes != size || err != nil {
+ t.Fatalf("ReadRune(0x%x) got 0x%x,%d not 0x%x,%d (err=%s)", r1, nr, nbytes, r1, size, err)
+ }
+ }
+}
+
+func TestWriteInvalidRune(t *testing.T) {
+ // Invalid runes, including negative ones, should be written as the
+ // replacement character.
+ for _, r := range []rune{-1, utf8.MaxRune + 1} {
+ var buf strings.Builder
+ w := NewWriter(&buf)
+ w.WriteRune(r)
+ w.Flush()
+ if s := buf.String(); s != "\uFFFD" {
+ t.Errorf("WriteRune(%d) wrote %q, not replacement character", r, s)
+ }
+ }
+}
+
+func TestReadStringAllocs(t *testing.T) {
+ if asan.Enabled {
+ t.Skip("test allocates more with -asan; see #70079")
+ }
+ r := strings.NewReader(" foo foo 42 42 42 42 42 42 42 42 4.2 4.2 4.2 4.2\n")
+ buf := NewReader(r)
+ allocs := testing.AllocsPerRun(100, func() {
+ r.Seek(0, io.SeekStart)
+ buf.Reset(r)
+
+ _, err := buf.ReadString('\n')
+ if err != nil {
+ t.Fatal(err)
+ }
+ })
+ if allocs != 1 {
+ t.Errorf("Unexpected number of allocations, got %f, want 1", allocs)
+ }
+}
+
+func TestWriter(t *testing.T) {
+ var data [8192]byte
+
+ for i := 0; i < len(data); i++ {
+ data[i] = byte(' ' + i%('~'-' '))
+ }
+ w := new(bytes.Buffer)
+ for i := 0; i < len(bufsizes); i++ {
+ for j := 0; j < len(bufsizes); j++ {
+ nwrite := bufsizes[i]
+ bs := bufsizes[j]
+
+ // Write nwrite bytes using buffer size bs.
+ // Check that the right amount makes it out
+ // and that the data is correct.
+
+ w.Reset()
+ buf := NewWriterSize(w, bs)
+ context := fmt.Sprintf("nwrite=%d bufsize=%d", nwrite, bs)
+ n, e1 := buf.Write(data[0:nwrite])
+ if e1 != nil || n != nwrite {
+ t.Errorf("%s: buf.Write %d = %d, %v", context, nwrite, n, e1)
+ continue
+ }
+ if e := buf.Flush(); e != nil {
+ t.Errorf("%s: buf.Flush = %v", context, e)
+ }
+
+ written := w.Bytes()
+ if len(written) != nwrite {
+ t.Errorf("%s: %d bytes written", context, len(written))
+ }
+ for l := 0; l < len(written); l++ {
+ if written[l] != data[l] {
+ t.Errorf("wrong bytes written")
+ t.Errorf("want=%q", data[:len(written)])
+ t.Errorf("have=%q", written)
+ }
+ }
+ }
+ }
+}
+
+func TestWriterAppend(t *testing.T) {
+ got := new(bytes.Buffer)
+ var want []byte
+ rn := rand.New(rand.NewSource(0))
+ w := NewWriterSize(got, 64)
+ for i := 0; i < 100; i++ {
+ // Obtain a buffer to append to.
+ b := w.AvailableBuffer()
+ if w.Available() != cap(b) {
+ t.Fatalf("Available() = %v, want %v", w.Available(), cap(b))
+ }
+
+ // While not recommended, it is valid to append to a shifted buffer.
+ // This forces Write to copy the input.
+ if rn.Intn(8) == 0 && cap(b) > 0 {
+ b = b[1:1:cap(b)]
+ }
+
+ // Append a random integer of varying width.
+ n := int64(rn.Intn(1 << rn.Intn(30)))
+ want = append(strconv.AppendInt(want, n, 10), ' ')
+ b = append(strconv.AppendInt(b, n, 10), ' ')
+ w.Write(b)
+ }
+ w.Flush()
+
+ if !bytes.Equal(got.Bytes(), want) {
+ t.Errorf("output mismatch:\ngot %s\nwant %s", got.Bytes(), want)
+ }
+}
+
+// Check that write errors are returned properly.
+
+type errorWriterTest struct {
+ n, m int
+ err error
+ expect error
+}
+
+func (w errorWriterTest) Write(p []byte) (int, error) {
+ return len(p) * w.n / w.m, w.err
+}
+
+var errorWriterTests = []errorWriterTest{
+ {0, 1, nil, io.ErrShortWrite},
+ {1, 2, nil, io.ErrShortWrite},
+ {1, 1, nil, nil},
+ {0, 1, io.ErrClosedPipe, io.ErrClosedPipe},
+ {1, 2, io.ErrClosedPipe, io.ErrClosedPipe},
+ {1, 1, io.ErrClosedPipe, io.ErrClosedPipe},
+}
+
+func TestWriteErrors(t *testing.T) {
+ for _, w := range errorWriterTests {
+ buf := NewWriter(w)
+ _, e := buf.Write([]byte("hello world"))
+ if e != nil {
+ t.Errorf("Write hello to %v: %v", w, e)
+ continue
+ }
+ // Two flushes, to verify the error is sticky.
+ for i := 0; i < 2; i++ {
+ e = buf.Flush()
+ if e != w.expect {
+ t.Errorf("Flush %d/2 %v: got %v, wanted %v", i+1, w, e, w.expect)
+ }
+ }
+ }
+}
+
+func TestNewReaderSizeIdempotent(t *testing.T) {
+ const BufSize = 1000
+ b := NewReaderSize(strings.NewReader("hello world"), BufSize)
+ // Does it recognize itself?
+ b1 := NewReaderSize(b, BufSize)
+ if b1 != b {
+ t.Error("NewReaderSize did not detect underlying Reader")
+ }
+ // Does it wrap if existing buffer is too small?
+ b2 := NewReaderSize(b, 2*BufSize)
+ if b2 == b {
+ t.Error("NewReaderSize did not enlarge buffer")
+ }
+}
+
+func TestNewWriterSizeIdempotent(t *testing.T) {
+ const BufSize = 1000
+ b := NewWriterSize(new(bytes.Buffer), BufSize)
+ // Does it recognize itself?
+ b1 := NewWriterSize(b, BufSize)
+ if b1 != b {
+ t.Error("NewWriterSize did not detect underlying Writer")
+ }
+ // Does it wrap if existing buffer is too small?
+ b2 := NewWriterSize(b, 2*BufSize)
+ if b2 == b {
+ t.Error("NewWriterSize did not enlarge buffer")
+ }
+}
+
+func TestWriteString(t *testing.T) {
+ const BufSize = 8
+ buf := new(strings.Builder)
+ b := NewWriterSize(buf, BufSize)
+ b.WriteString("0") // easy
+ b.WriteString("123456") // still easy
+ b.WriteString("7890") // easy after flush
+ b.WriteString("abcdefghijklmnopqrstuvwxy") // hard
+ b.WriteString("z")
+ if err := b.Flush(); err != nil {
+ t.Error("WriteString", err)
+ }
+ s := "01234567890abcdefghijklmnopqrstuvwxyz"
+ if buf.String() != s {
+ t.Errorf("WriteString wants %q gets %q", s, buf.String())
+ }
+}
+
+func TestWriteStringStringWriter(t *testing.T) {
+ const BufSize = 8
+ {
+ tw := &teststringwriter{}
+ b := NewWriterSize(tw, BufSize)
+ b.WriteString("1234")
+ tw.check(t, "", "")
+ b.WriteString("56789012") // longer than BufSize
+ tw.check(t, "12345678", "") // but not enough (after filling the partially-filled buffer)
+ b.Flush()
+ tw.check(t, "123456789012", "")
+ }
+ {
+ tw := &teststringwriter{}
+ b := NewWriterSize(tw, BufSize)
+ b.WriteString("123456789") // long string, empty buffer:
+ tw.check(t, "", "123456789") // use WriteString
+ }
+ {
+ tw := &teststringwriter{}
+ b := NewWriterSize(tw, BufSize)
+ b.WriteString("abc")
+ tw.check(t, "", "")
+ b.WriteString("123456789012345") // long string, non-empty buffer
+ tw.check(t, "abc12345", "6789012345") // use Write and then WriteString since the remaining part is still longer than BufSize
+ }
+ {
+ tw := &teststringwriter{}
+ b := NewWriterSize(tw, BufSize)
+ b.Write([]byte("abc")) // same as above, but use Write instead of WriteString
+ tw.check(t, "", "")
+ b.WriteString("123456789012345")
+ tw.check(t, "abc12345", "6789012345") // same as above
+ }
+}
+
+type teststringwriter struct {
+ write string
+ writeString string
+}
+
+func (w *teststringwriter) Write(b []byte) (int, error) {
+ w.write += string(b)
+ return len(b), nil
+}
+
+func (w *teststringwriter) WriteString(s string) (int, error) {
+ w.writeString += s
+ return len(s), nil
+}
+
+func (w *teststringwriter) check(t *testing.T, write, writeString string) {
+ t.Helper()
+ if w.write != write {
+ t.Errorf("write: expected %q, got %q", write, w.write)
+ }
+ if w.writeString != writeString {
+ t.Errorf("writeString: expected %q, got %q", writeString, w.writeString)
+ }
+}
+
+func TestBufferFull(t *testing.T) {
+ const longString = "And now, hello, world! It is the time for all good men to come to the aid of their party"
+ buf := NewReaderSize(strings.NewReader(longString), minReadBufferSize)
+ line, err := buf.ReadSlice('!')
+ if string(line) != "And now, hello, " || err != ErrBufferFull {
+ t.Errorf("first ReadSlice(,) = %q, %v", line, err)
+ }
+ line, err = buf.ReadSlice('!')
+ if string(line) != "world!" || err != nil {
+ t.Errorf("second ReadSlice(,) = %q, %v", line, err)
+ }
+}
+
+func TestPeek(t *testing.T) {
+ p := make([]byte, 10)
+ // string is 16 (minReadBufferSize) long.
+ buf := NewReaderSize(strings.NewReader("abcdefghijklmnop"), minReadBufferSize)
+ if s, err := buf.Peek(1); string(s) != "a" || err != nil {
+ t.Fatalf("want %q got %q, err=%v", "a", string(s), err)
+ }
+ if s, err := buf.Peek(4); string(s) != "abcd" || err != nil {
+ t.Fatalf("want %q got %q, err=%v", "abcd", string(s), err)
+ }
+ if _, err := buf.Peek(-1); err != ErrNegativeCount {
+ t.Fatalf("want ErrNegativeCount got %v", err)
+ }
+ if s, err := buf.Peek(32); string(s) != "abcdefghijklmnop" || err != ErrBufferFull {
+ t.Fatalf("want %q, ErrBufFull got %q, err=%v", "abcdefghijklmnop", string(s), err)
+ }
+ if _, err := buf.Read(p[0:3]); string(p[0:3]) != "abc" || err != nil {
+ t.Fatalf("want %q got %q, err=%v", "abc", string(p[0:3]), err)
+ }
+ if s, err := buf.Peek(1); string(s) != "d" || err != nil {
+ t.Fatalf("want %q got %q, err=%v", "d", string(s), err)
+ }
+ if s, err := buf.Peek(2); string(s) != "de" || err != nil {
+ t.Fatalf("want %q got %q, err=%v", "de", string(s), err)
+ }
+ if _, err := buf.Read(p[0:3]); string(p[0:3]) != "def" || err != nil {
+ t.Fatalf("want %q got %q, err=%v", "def", string(p[0:3]), err)
+ }
+ if s, err := buf.Peek(4); string(s) != "ghij" || err != nil {
+ t.Fatalf("want %q got %q, err=%v", "ghij", string(s), err)
+ }
+ if _, err := buf.Read(p[0:]); string(p[0:]) != "ghijklmnop" || err != nil {
+ t.Fatalf("want %q got %q, err=%v", "ghijklmnop", string(p[0:minReadBufferSize]), err)
+ }
+ if s, err := buf.Peek(0); string(s) != "" || err != nil {
+ t.Fatalf("want %q got %q, err=%v", "", string(s), err)
+ }
+ if _, err := buf.Peek(1); err != io.EOF {
+ t.Fatalf("want EOF got %v", err)
+ }
+
+ // Test for issue 3022, not exposing a reader's error on a successful Peek.
+ buf = NewReaderSize(dataAndEOFReader("abcd"), 32)
+ if s, err := buf.Peek(2); string(s) != "ab" || err != nil {
+ t.Errorf(`Peek(2) on "abcd", EOF = %q, %v; want "ab", nil`, string(s), err)
+ }
+ if s, err := buf.Peek(4); string(s) != "abcd" || err != nil {
+ t.Errorf(`Peek(4) on "abcd", EOF = %q, %v; want "abcd", nil`, string(s), err)
+ }
+ if n, err := buf.Read(p[0:5]); string(p[0:n]) != "abcd" || err != nil {
+ t.Fatalf("Read after peek = %q, %v; want abcd, EOF", p[0:n], err)
+ }
+ if n, err := buf.Read(p[0:1]); string(p[0:n]) != "" || err != io.EOF {
+ t.Fatalf(`second Read after peek = %q, %v; want "", EOF`, p[0:n], err)
+ }
+}
+
+type dataAndEOFReader string
+
+func (r dataAndEOFReader) Read(p []byte) (int, error) {
+ return copy(p, r), io.EOF
+}
+
+func TestPeekThenUnreadRune(t *testing.T) {
+ // This sequence used to cause a crash.
+ r := NewReader(strings.NewReader("x"))
+ r.ReadRune()
+ r.Peek(1)
+ r.UnreadRune()
+ r.ReadRune() // Used to panic here
+}
+
+var testOutput = []byte("0123456789abcdefghijklmnopqrstuvwxy")
+var testInput = []byte("012\n345\n678\n9ab\ncde\nfgh\nijk\nlmn\nopq\nrst\nuvw\nxy")
+var testInputrn = []byte("012\r\n345\r\n678\r\n9ab\r\ncde\r\nfgh\r\nijk\r\nlmn\r\nopq\r\nrst\r\nuvw\r\nxy\r\n\n\r\n")
+
+// TestReader wraps a []byte and returns reads of a specific length.
+type testReader struct {
+ data []byte
+ stride int
+}
+
+func (t *testReader) Read(buf []byte) (n int, err error) {
+ n = t.stride
+ if n > len(t.data) {
+ n = len(t.data)
+ }
+ if n > len(buf) {
+ n = len(buf)
+ }
+ copy(buf, t.data)
+ t.data = t.data[n:]
+ if len(t.data) == 0 {
+ err = io.EOF
+ }
+ return
+}
+
+func testReadLine(t *testing.T, input []byte) {
+ for stride := 1; stride < 2; stride++ {
+ done := 0
+ reader := testReader{input, stride}
+ l := NewReaderSize(&reader, len(input)+1)
+ for {
+ line, isPrefix, err := l.ReadLine()
+ if len(line) > 0 && err != nil {
+ t.Errorf("ReadLine returned both data and error: %s", err)
+ }
+ if isPrefix {
+ t.Errorf("ReadLine returned prefix")
+ }
+ if err != nil {
+ if err != io.EOF {
+ t.Fatalf("Got unknown error: %s", err)
+ }
+ break
+ }
+ if want := testOutput[done : done+len(line)]; !bytes.Equal(want, line) {
+ t.Errorf("Bad line at stride %d: want: %x got: %x", stride, want, line)
+ }
+ done += len(line)
+ }
+ if done != len(testOutput) {
+ t.Errorf("ReadLine didn't return everything: got: %d, want: %d (stride: %d)", done, len(testOutput), stride)
+ }
+ }
+}
+
+func TestReadLine(t *testing.T) {
+ testReadLine(t, testInput)
+ testReadLine(t, testInputrn)
+}
+
+func TestLineTooLong(t *testing.T) {
+ data := make([]byte, 0)
+ for i := 0; i < minReadBufferSize*5/2; i++ {
+ data = append(data, '0'+byte(i%10))
+ }
+ buf := bytes.NewReader(data)
+ l := NewReaderSize(buf, minReadBufferSize)
+ line, isPrefix, err := l.ReadLine()
+ if !isPrefix || !bytes.Equal(line, data[:minReadBufferSize]) || err != nil {
+ t.Errorf("bad result for first line: got %q want %q %v", line, data[:minReadBufferSize], err)
+ }
+ data = data[len(line):]
+ line, isPrefix, err = l.ReadLine()
+ if !isPrefix || !bytes.Equal(line, data[:minReadBufferSize]) || err != nil {
+ t.Errorf("bad result for second line: got %q want %q %v", line, data[:minReadBufferSize], err)
+ }
+ data = data[len(line):]
+ line, isPrefix, err = l.ReadLine()
+ if isPrefix || !bytes.Equal(line, data[:minReadBufferSize/2]) || err != nil {
+ t.Errorf("bad result for third line: got %q want %q %v", line, data[:minReadBufferSize/2], err)
+ }
+ line, isPrefix, err = l.ReadLine()
+ if isPrefix || err == nil {
+ t.Errorf("expected no more lines: %x %s", line, err)
+ }
+}
+
+func TestReadAfterLines(t *testing.T) {
+ line1 := "this is line1"
+ restData := "this is line2\nthis is line 3\n"
+ inbuf := bytes.NewReader([]byte(line1 + "\n" + restData))
+ outbuf := new(strings.Builder)
+ maxLineLength := len(line1) + len(restData)/2
+ l := NewReaderSize(inbuf, maxLineLength)
+ line, isPrefix, err := l.ReadLine()
+ if isPrefix || err != nil || string(line) != line1 {
+ t.Errorf("bad result for first line: isPrefix=%v err=%v line=%q", isPrefix, err, string(line))
+ }
+ n, err := io.Copy(outbuf, l)
+ if int(n) != len(restData) || err != nil {
+ t.Errorf("bad result for Read: n=%d err=%v", n, err)
+ }
+ if outbuf.String() != restData {
+ t.Errorf("bad result for Read: got %q; expected %q", outbuf.String(), restData)
+ }
+}
+
+func TestReadEmptyBuffer(t *testing.T) {
+ l := NewReaderSize(new(bytes.Buffer), minReadBufferSize)
+ line, isPrefix, err := l.ReadLine()
+ if err != io.EOF {
+ t.Errorf("expected EOF from ReadLine, got '%s' %t %s", line, isPrefix, err)
+ }
+}
+
+func TestLinesAfterRead(t *testing.T) {
+ l := NewReaderSize(bytes.NewReader([]byte("foo")), minReadBufferSize)
+ _, err := io.ReadAll(l)
+ if err != nil {
+ t.Error(err)
+ return
+ }
+
+ line, isPrefix, err := l.ReadLine()
+ if err != io.EOF {
+ t.Errorf("expected EOF from ReadLine, got '%s' %t %s", line, isPrefix, err)
+ }
+}
+
+func TestReadLineNonNilLineOrError(t *testing.T) {
+ r := NewReader(strings.NewReader("line 1\n"))
+ for i := 0; i < 2; i++ {
+ l, _, err := r.ReadLine()
+ if l != nil && err != nil {
+ t.Fatalf("on line %d/2; ReadLine=%#v, %v; want non-nil line or Error, but not both",
+ i+1, l, err)
+ }
+ }
+}
+
+type readLineResult struct {
+ line []byte
+ isPrefix bool
+ err error
+}
+
+var readLineNewlinesTests = []struct {
+ input string
+ expect []readLineResult
+}{
+ {"012345678901234\r\n012345678901234\r\n", []readLineResult{
+ {[]byte("012345678901234"), true, nil},
+ {nil, false, nil},
+ {[]byte("012345678901234"), true, nil},
+ {nil, false, nil},
+ {nil, false, io.EOF},
+ }},
+ {"0123456789012345\r012345678901234\r", []readLineResult{
+ {[]byte("0123456789012345"), true, nil},
+ {[]byte("\r012345678901234"), true, nil},
+ {[]byte("\r"), false, nil},
+ {nil, false, io.EOF},
+ }},
+}
+
+func TestReadLineNewlines(t *testing.T) {
+ for _, e := range readLineNewlinesTests {
+ testReadLineNewlines(t, e.input, e.expect)
+ }
+}
+
+func testReadLineNewlines(t *testing.T, input string, expect []readLineResult) {
+ b := NewReaderSize(strings.NewReader(input), minReadBufferSize)
+ for i, e := range expect {
+ line, isPrefix, err := b.ReadLine()
+ if !bytes.Equal(line, e.line) {
+ t.Errorf("%q call %d, line == %q, want %q", input, i, line, e.line)
+ return
+ }
+ if isPrefix != e.isPrefix {
+ t.Errorf("%q call %d, isPrefix == %v, want %v", input, i, isPrefix, e.isPrefix)
+ return
+ }
+ if err != e.err {
+ t.Errorf("%q call %d, err == %v, want %v", input, i, err, e.err)
+ return
+ }
+ }
+}
+
+func createTestInput(n int) []byte {
+ input := make([]byte, n)
+ for i := range input {
+ // 101 and 251 are arbitrary prime numbers.
+ // The idea is to create an input sequence
+ // which doesn't repeat too frequently.
+ input[i] = byte(i % 251)
+ if i%101 == 0 {
+ input[i] ^= byte(i / 101)
+ }
+ }
+ return input
+}
+
+func TestReaderWriteTo(t *testing.T) {
+ input := createTestInput(8192)
+ r := NewReader(onlyReader{bytes.NewReader(input)})
+ w := new(bytes.Buffer)
+ if n, err := r.WriteTo(w); err != nil || n != int64(len(input)) {
+ t.Fatalf("r.WriteTo(w) = %d, %v, want %d, nil", n, err, len(input))
+ }
+
+ for i, val := range w.Bytes() {
+ if val != input[i] {
+ t.Errorf("after write: out[%d] = %#x, want %#x", i, val, input[i])
+ }
+ }
+}
+
+type errorWriterToTest struct {
+ rn, wn int
+ rerr, werr error
+ expected error
+}
+
+func (r errorWriterToTest) Read(p []byte) (int, error) {
+ return len(p) * r.rn, r.rerr
+}
+
+func (w errorWriterToTest) Write(p []byte) (int, error) {
+ return len(p) * w.wn, w.werr
+}
+
+var errorWriterToTests = []errorWriterToTest{
+ {1, 0, nil, io.ErrClosedPipe, io.ErrClosedPipe},
+ {0, 1, io.ErrClosedPipe, nil, io.ErrClosedPipe},
+ {0, 0, io.ErrUnexpectedEOF, io.ErrClosedPipe, io.ErrUnexpectedEOF},
+ {0, 1, io.EOF, nil, nil},
+}
+
+func TestReaderWriteToErrors(t *testing.T) {
+ for i, rw := range errorWriterToTests {
+ r := NewReader(rw)
+ if _, err := r.WriteTo(rw); err != rw.expected {
+ t.Errorf("r.WriteTo(errorWriterToTests[%d]) = _, %v, want _,%v", i, err, rw.expected)
+ }
+ }
+}
+
+func TestWriterReadFrom(t *testing.T) {
+ ws := []func(io.Writer) io.Writer{
+ func(w io.Writer) io.Writer { return onlyWriter{w} },
+ func(w io.Writer) io.Writer { return w },
+ }
+
+ rs := []func(io.Reader) io.Reader{
+ iotest.DataErrReader,
+ func(r io.Reader) io.Reader { return r },
+ }
+
+ for ri, rfunc := range rs {
+ for wi, wfunc := range ws {
+ input := createTestInput(8192)
+ b := new(strings.Builder)
+ w := NewWriter(wfunc(b))
+ r := rfunc(bytes.NewReader(input))
+ if n, err := w.ReadFrom(r); err != nil || n != int64(len(input)) {
+ t.Errorf("ws[%d],rs[%d]: w.ReadFrom(r) = %d, %v, want %d, nil", wi, ri, n, err, len(input))
+ continue
+ }
+ if err := w.Flush(); err != nil {
+ t.Errorf("Flush returned %v", err)
+ continue
+ }
+ if got, want := b.String(), string(input); got != want {
+ t.Errorf("ws[%d], rs[%d]:\ngot %q\nwant %q\n", wi, ri, got, want)
+ }
+ }
+ }
+}
+
+type errorReaderFromTest struct {
+ rn, wn int
+ rerr, werr error
+ expected error
+}
+
+func (r errorReaderFromTest) Read(p []byte) (int, error) {
+ return len(p) * r.rn, r.rerr
+}
+
+func (w errorReaderFromTest) Write(p []byte) (int, error) {
+ return len(p) * w.wn, w.werr
+}
+
+var errorReaderFromTests = []errorReaderFromTest{
+ {0, 1, io.EOF, nil, nil},
+ {1, 1, io.EOF, nil, nil},
+ {0, 1, io.ErrClosedPipe, nil, io.ErrClosedPipe},
+ {0, 0, io.ErrClosedPipe, io.ErrShortWrite, io.ErrClosedPipe},
+ {1, 0, nil, io.ErrShortWrite, io.ErrShortWrite},
+}
+
+func TestWriterReadFromErrors(t *testing.T) {
+ for i, rw := range errorReaderFromTests {
+ w := NewWriter(rw)
+ if _, err := w.ReadFrom(rw); err != rw.expected {
+ t.Errorf("w.ReadFrom(errorReaderFromTests[%d]) = _, %v, want _,%v", i, err, rw.expected)
+ }
+ }
+}
+
+// TestWriterReadFromCounts tests that using io.Copy to copy into a
+// bufio.Writer does not prematurely flush the buffer. For example, when
+// buffering writes to a network socket, excessive network writes should be
+// avoided.
+func TestWriterReadFromCounts(t *testing.T) {
+ var w0 writeCountingDiscard
+ b0 := NewWriterSize(&w0, 1234)
+ b0.WriteString(strings.Repeat("x", 1000))
+ if w0 != 0 {
+ t.Fatalf("write 1000 'x's: got %d writes, want 0", w0)
+ }
+ b0.WriteString(strings.Repeat("x", 200))
+ if w0 != 0 {
+ t.Fatalf("write 1200 'x's: got %d writes, want 0", w0)
+ }
+ io.Copy(b0, onlyReader{strings.NewReader(strings.Repeat("x", 30))})
+ if w0 != 0 {
+ t.Fatalf("write 1230 'x's: got %d writes, want 0", w0)
+ }
+ io.Copy(b0, onlyReader{strings.NewReader(strings.Repeat("x", 9))})
+ if w0 != 1 {
+ t.Fatalf("write 1239 'x's: got %d writes, want 1", w0)
+ }
+
+ var w1 writeCountingDiscard
+ b1 := NewWriterSize(&w1, 1234)
+ b1.WriteString(strings.Repeat("x", 1200))
+ b1.Flush()
+ if w1 != 1 {
+ t.Fatalf("flush 1200 'x's: got %d writes, want 1", w1)
+ }
+ b1.WriteString(strings.Repeat("x", 89))
+ if w1 != 1 {
+ t.Fatalf("write 1200 + 89 'x's: got %d writes, want 1", w1)
+ }
+ io.Copy(b1, onlyReader{strings.NewReader(strings.Repeat("x", 700))})
+ if w1 != 1 {
+ t.Fatalf("write 1200 + 789 'x's: got %d writes, want 1", w1)
+ }
+ io.Copy(b1, onlyReader{strings.NewReader(strings.Repeat("x", 600))})
+ if w1 != 2 {
+ t.Fatalf("write 1200 + 1389 'x's: got %d writes, want 2", w1)
+ }
+ b1.Flush()
+ if w1 != 3 {
+ t.Fatalf("flush 1200 + 1389 'x's: got %d writes, want 3", w1)
+ }
+}
+
+// A writeCountingDiscard is like io.Discard and counts the number of times
+// Write is called on it.
+type writeCountingDiscard int
+
+func (w *writeCountingDiscard) Write(p []byte) (int, error) {
+ *w++
+ return len(p), nil
+}
+
+type negativeReader int
+
+func (r *negativeReader) Read([]byte) (int, error) { return -1, nil }
+
+func TestNegativeRead(t *testing.T) {
+ // should panic with a description pointing at the reader, not at itself.
+ // (should NOT panic with slice index error, for example.)
+ b := NewReader(new(negativeReader))
+ defer func() {
+ switch err := recover().(type) {
+ case nil:
+ t.Fatal("read did not panic")
+ case error:
+ if !strings.Contains(err.Error(), "reader returned negative count from Read") {
+ t.Fatalf("wrong panic: %v", err)
+ }
+ default:
+ t.Fatalf("unexpected panic value: %T(%v)", err, err)
+ }
+ }()
+ b.Read(make([]byte, 100))
+}
+
+var errFake = errors.New("fake error")
+
+type errorThenGoodReader struct {
+ didErr bool
+ nread int
+}
+
+func (r *errorThenGoodReader) Read(p []byte) (int, error) {
+ r.nread++
+ if !r.didErr {
+ r.didErr = true
+ return 0, errFake
+ }
+ return len(p), nil
+}
+
+func TestReaderClearError(t *testing.T) {
+ r := &errorThenGoodReader{}
+ b := NewReader(r)
+ buf := make([]byte, 1)
+ if _, err := b.Read(nil); err != nil {
+ t.Fatalf("1st nil Read = %v; want nil", err)
+ }
+ if _, err := b.Read(buf); err != errFake {
+ t.Fatalf("1st Read = %v; want errFake", err)
+ }
+ if _, err := b.Read(nil); err != nil {
+ t.Fatalf("2nd nil Read = %v; want nil", err)
+ }
+ if _, err := b.Read(buf); err != nil {
+ t.Fatalf("3rd Read with buffer = %v; want nil", err)
+ }
+ if r.nread != 2 {
+ t.Errorf("num reads = %d; want 2", r.nread)
+ }
+}
+
+// Test for golang.org/issue/5947
+func TestWriterReadFromWhileFull(t *testing.T) {
+ buf := new(bytes.Buffer)
+ w := NewWriterSize(buf, 10)
+
+ // Fill buffer exactly.
+ n, err := w.Write([]byte("0123456789"))
+ if n != 10 || err != nil {
+ t.Fatalf("Write returned (%v, %v), want (10, nil)", n, err)
+ }
+
+ // Use ReadFrom to read in some data.
+ n2, err := w.ReadFrom(strings.NewReader("abcdef"))
+ if n2 != 6 || err != nil {
+ t.Fatalf("ReadFrom returned (%v, %v), want (6, nil)", n2, err)
+ }
+}
+
+type emptyThenNonEmptyReader struct {
+ r io.Reader
+ n int
+}
+
+func (r *emptyThenNonEmptyReader) Read(p []byte) (int, error) {
+ if r.n <= 0 {
+ return r.r.Read(p)
+ }
+ r.n--
+ return 0, nil
+}
+
+// Test for golang.org/issue/7611
+func TestWriterReadFromUntilEOF(t *testing.T) {
+ buf := new(bytes.Buffer)
+ w := NewWriterSize(buf, 5)
+
+ // Partially fill buffer
+ n, err := w.Write([]byte("0123"))
+ if n != 4 || err != nil {
+ t.Fatalf("Write returned (%v, %v), want (4, nil)", n, err)
+ }
+
+ // Use ReadFrom to read in some data.
+ r := &emptyThenNonEmptyReader{r: strings.NewReader("abcd"), n: 3}
+ n2, err := w.ReadFrom(r)
+ if n2 != 4 || err != nil {
+ t.Fatalf("ReadFrom returned (%v, %v), want (4, nil)", n2, err)
+ }
+ w.Flush()
+ if got, want := buf.String(), "0123abcd"; got != want {
+ t.Fatalf("buf.Bytes() returned %q, want %q", got, want)
+ }
+}
+
+func TestWriterReadFromErrNoProgress(t *testing.T) {
+ buf := new(bytes.Buffer)
+ w := NewWriterSize(buf, 5)
+
+ // Partially fill buffer
+ n, err := w.Write([]byte("0123"))
+ if n != 4 || err != nil {
+ t.Fatalf("Write returned (%v, %v), want (4, nil)", n, err)
+ }
+
+ // Use ReadFrom to read in some data.
+ r := &emptyThenNonEmptyReader{r: strings.NewReader("abcd"), n: 100}
+ n2, err := w.ReadFrom(r)
+ if n2 != 0 || err != io.ErrNoProgress {
+ t.Fatalf("buf.Bytes() returned (%v, %v), want (0, io.ErrNoProgress)", n2, err)
+ }
+}
+
+type readFromWriter struct {
+ buf []byte
+ writeBytes int
+ readFromBytes int
+}
+
+func (w *readFromWriter) Write(p []byte) (int, error) {
+ w.buf = append(w.buf, p...)
+ w.writeBytes += len(p)
+ return len(p), nil
+}
+
+func (w *readFromWriter) ReadFrom(r io.Reader) (int64, error) {
+ b, err := io.ReadAll(r)
+ w.buf = append(w.buf, b...)
+ w.readFromBytes += len(b)
+ return int64(len(b)), err
+}
+
+// Test that calling (*Writer).ReadFrom with a partially-filled buffer
+// fills the buffer before switching over to ReadFrom.
+func TestWriterReadFromWithBufferedData(t *testing.T) {
+ const bufsize = 16
+
+ input := createTestInput(64)
+ rfw := &readFromWriter{}
+ w := NewWriterSize(rfw, bufsize)
+
+ const writeSize = 8
+ if n, err := w.Write(input[:writeSize]); n != writeSize || err != nil {
+ t.Errorf("w.Write(%v bytes) = %v, %v; want %v, nil", writeSize, n, err, writeSize)
+ }
+ n, err := w.ReadFrom(bytes.NewReader(input[writeSize:]))
+ if wantn := len(input[writeSize:]); int(n) != wantn || err != nil {
+ t.Errorf("io.Copy(w, %v bytes) = %v, %v; want %v, nil", wantn, n, err, wantn)
+ }
+ if err := w.Flush(); err != nil {
+ t.Errorf("w.Flush() = %v, want nil", err)
+ }
+
+ if got, want := rfw.writeBytes, bufsize; got != want {
+ t.Errorf("wrote %v bytes with Write, want %v", got, want)
+ }
+ if got, want := rfw.readFromBytes, len(input)-bufsize; got != want {
+ t.Errorf("wrote %v bytes with ReadFrom, want %v", got, want)
+ }
+}
+
+func TestReadZero(t *testing.T) {
+ for _, size := range []int{100, 2} {
+ t.Run(fmt.Sprintf("bufsize=%d", size), func(t *testing.T) {
+ r := io.MultiReader(strings.NewReader("abc"), &emptyThenNonEmptyReader{r: strings.NewReader("def"), n: 1})
+ br := NewReaderSize(r, size)
+ want := func(s string, wantErr error) {
+ p := make([]byte, 50)
+ n, err := br.Read(p)
+ if err != wantErr || n != len(s) || string(p[:n]) != s {
+ t.Fatalf("read(%d) = %q, %v, want %q, %v", len(p), string(p[:n]), err, s, wantErr)
+ }
+ t.Logf("read(%d) = %q, %v", len(p), string(p[:n]), err)
+ }
+ want("abc", nil)
+ want("", nil)
+ want("def", nil)
+ want("", io.EOF)
+ })
+ }
+}
+
+func TestReaderReset(t *testing.T) {
+ checkAll := func(r *Reader, want string) {
+ t.Helper()
+ all, err := io.ReadAll(r)
+ if err != nil {
+ t.Fatal(err)
+ }
+ if string(all) != want {
+ t.Errorf("ReadAll returned %q, want %q", all, want)
+ }
+ }
+
+ r := NewReader(strings.NewReader("foo foo"))
+ buf := make([]byte, 3)
+ r.Read(buf)
+ if string(buf) != "foo" {
+ t.Errorf("buf = %q; want foo", buf)
+ }
+
+ r.Reset(strings.NewReader("bar bar"))
+ checkAll(r, "bar bar")
+
+ *r = Reader{} // zero out the Reader
+ r.Reset(strings.NewReader("bar bar"))
+ checkAll(r, "bar bar")
+
+ // Wrap a reader and then Reset to that reader.
+ r.Reset(strings.NewReader("recur"))
+ r2 := NewReader(r)
+ checkAll(r2, "recur")
+ r.Reset(strings.NewReader("recur2"))
+ r2.Reset(r)
+ checkAll(r2, "recur2")
+}
+
+func TestWriterReset(t *testing.T) {
+ var buf1, buf2, buf3, buf4, buf5 strings.Builder
+ w := NewWriter(&buf1)
+ w.WriteString("foo")
+
+ w.Reset(&buf2) // and not flushed
+ w.WriteString("bar")
+ w.Flush()
+ if buf1.String() != "" {
+ t.Errorf("buf1 = %q; want empty", buf1.String())
+ }
+ if buf2.String() != "bar" {
+ t.Errorf("buf2 = %q; want bar", buf2.String())
+ }
+
+ *w = Writer{} // zero out the Writer
+ w.Reset(&buf3) // and not flushed
+ w.WriteString("bar")
+ w.Flush()
+ if buf1.String() != "" {
+ t.Errorf("buf1 = %q; want empty", buf1.String())
+ }
+ if buf3.String() != "bar" {
+ t.Errorf("buf3 = %q; want bar", buf3.String())
+ }
+
+ // Wrap a writer and then Reset to that writer.
+ w.Reset(&buf4)
+ w2 := NewWriter(w)
+ w2.WriteString("recur")
+ w2.Flush()
+ if buf4.String() != "recur" {
+ t.Errorf("buf4 = %q, want %q", buf4.String(), "recur")
+ }
+ w.Reset(&buf5)
+ w2.Reset(w)
+ w2.WriteString("recur2")
+ w2.Flush()
+ if buf5.String() != "recur2" {
+ t.Errorf("buf5 = %q, want %q", buf5.String(), "recur2")
+ }
+}
+
+func TestReaderDiscard(t *testing.T) {
+ tests := []struct {
+ name string
+ r io.Reader
+ bufSize int // 0 means 16
+ peekSize int
+
+ n int // input to Discard
+
+ want int // from Discard
+ wantErr error // from Discard
+
+ wantBuffered int
+ }{
+ {
+ name: "normal case",
+ r: strings.NewReader("abcdefghijklmnopqrstuvwxyz"),
+ peekSize: 16,
+ n: 6,
+ want: 6,
+ wantBuffered: 10,
+ },
+ {
+ name: "discard causing read",
+ r: strings.NewReader("abcdefghijklmnopqrstuvwxyz"),
+ n: 6,
+ want: 6,
+ wantBuffered: 10,
+ },
+ {
+ name: "discard all without peek",
+ r: strings.NewReader("abcdefghijklmnopqrstuvwxyz"),
+ n: 26,
+ want: 26,
+ wantBuffered: 0,
+ },
+ {
+ name: "discard more than end",
+ r: strings.NewReader("abcdefghijklmnopqrstuvwxyz"),
+ n: 27,
+ want: 26,
+ wantErr: io.EOF,
+ wantBuffered: 0,
+ },
+ // Any error from filling shouldn't show up until we
+ // get past the valid bytes. Here we return 5 valid bytes at the same time
+ // as an error, but test that we don't see the error from Discard.
+ {
+ name: "fill error, discard less",
+ r: newScriptedReader(func(p []byte) (n int, err error) {
+ if len(p) < 5 {
+ panic("unexpected small read")
+ }
+ return 5, errors.New("5-then-error")
+ }),
+ n: 4,
+ want: 4,
+ wantErr: nil,
+ wantBuffered: 1,
+ },
+ {
+ name: "fill error, discard equal",
+ r: newScriptedReader(func(p []byte) (n int, err error) {
+ if len(p) < 5 {
+ panic("unexpected small read")
+ }
+ return 5, errors.New("5-then-error")
+ }),
+ n: 5,
+ want: 5,
+ wantErr: nil,
+ wantBuffered: 0,
+ },
+ {
+ name: "fill error, discard more",
+ r: newScriptedReader(func(p []byte) (n int, err error) {
+ if len(p) < 5 {
+ panic("unexpected small read")
+ }
+ return 5, errors.New("5-then-error")
+ }),
+ n: 6,
+ want: 5,
+ wantErr: errors.New("5-then-error"),
+ wantBuffered: 0,
+ },
+ // Discard of 0 shouldn't cause a read:
+ {
+ name: "discard zero",
+ r: newScriptedReader(), // will panic on Read
+ n: 0,
+ want: 0,
+ wantErr: nil,
+ wantBuffered: 0,
+ },
+ {
+ name: "discard negative",
+ r: newScriptedReader(), // will panic on Read
+ n: -1,
+ want: 0,
+ wantErr: ErrNegativeCount,
+ wantBuffered: 0,
+ },
+ }
+ for _, tt := range tests {
+ br := NewReaderSize(tt.r, tt.bufSize)
+ if tt.peekSize > 0 {
+ peekBuf, err := br.Peek(tt.peekSize)
+ if err != nil {
+ t.Errorf("%s: Peek(%d): %v", tt.name, tt.peekSize, err)
+ continue
+ }
+ if len(peekBuf) != tt.peekSize {
+ t.Errorf("%s: len(Peek(%d)) = %v; want %v", tt.name, tt.peekSize, len(peekBuf), tt.peekSize)
+ continue
+ }
+ }
+ discarded, err := br.Discard(tt.n)
+ if ge, we := fmt.Sprint(err), fmt.Sprint(tt.wantErr); discarded != tt.want || ge != we {
+ t.Errorf("%s: Discard(%d) = (%v, %v); want (%v, %v)", tt.name, tt.n, discarded, ge, tt.want, we)
+ continue
+ }
+ if bn := br.Buffered(); bn != tt.wantBuffered {
+ t.Errorf("%s: after Discard, Buffered = %d; want %d", tt.name, bn, tt.wantBuffered)
+ }
+ }
+
+}
+
+func TestReaderSize(t *testing.T) {
+ if got, want := NewReader(nil).Size(), DefaultBufSize; got != want {
+ t.Errorf("NewReader's Reader.Size = %d; want %d", got, want)
+ }
+ if got, want := NewReaderSize(nil, 1234).Size(), 1234; got != want {
+ t.Errorf("NewReaderSize's Reader.Size = %d; want %d", got, want)
+ }
+}
+
+func TestWriterSize(t *testing.T) {
+ if got, want := NewWriter(nil).Size(), DefaultBufSize; got != want {
+ t.Errorf("NewWriter's Writer.Size = %d; want %d", got, want)
+ }
+ if got, want := NewWriterSize(nil, 1234).Size(), 1234; got != want {
+ t.Errorf("NewWriterSize's Writer.Size = %d; want %d", got, want)
+ }
+}
+
+// An onlyReader only implements io.Reader, no matter what other methods the underlying implementation may have.
+type onlyReader struct {
+ io.Reader
+}
+
+// An onlyWriter only implements io.Writer, no matter what other methods the underlying implementation may have.
+type onlyWriter struct {
+ io.Writer
+}
+
+// A scriptedReader is an io.Reader that executes its steps sequentially.
+type scriptedReader []func(p []byte) (n int, err error)
+
+func (sr *scriptedReader) Read(p []byte) (n int, err error) {
+ if len(*sr) == 0 {
+ panic("too many Read calls on scripted Reader. No steps remain.")
+ }
+ step := (*sr)[0]
+ *sr = (*sr)[1:]
+ return step(p)
+}
+
+func newScriptedReader(steps ...func(p []byte) (n int, err error)) io.Reader {
+ sr := scriptedReader(steps)
+ return &sr
+}
+
+// eofReader returns the number of bytes read and io.EOF for the read that consumes the last of the content.
+type eofReader struct {
+ buf []byte
+}
+
+func (r *eofReader) Read(p []byte) (int, error) {
+ read := copy(p, r.buf)
+ r.buf = r.buf[read:]
+
+ switch read {
+ case 0, len(r.buf):
+ // As allowed in the documentation, this will return io.EOF
+ // in the same call that consumes the last of the data.
+ // https://godoc.org/io#Reader
+ return read, io.EOF
+ }
+
+ return read, nil
+}
+
+func TestPartialReadEOF(t *testing.T) {
+ src := make([]byte, 10)
+ eofR := &eofReader{buf: src}
+ r := NewReader(eofR)
+
+ // Start by reading 5 of the 10 available bytes.
+ dest := make([]byte, 5)
+ read, err := r.Read(dest)
+ if err != nil {
+ t.Fatalf("unexpected error: %v", err)
+ }
+ if n := len(dest); read != n {
+ t.Fatalf("read %d bytes; wanted %d bytes", read, n)
+ }
+
+ // The Reader should have buffered all the content from the io.Reader.
+ if n := len(eofR.buf); n != 0 {
+ t.Fatalf("got %d bytes left in bufio.Reader source; want 0 bytes", n)
+ }
+ // To prove the point, check that there are still 5 bytes available to read.
+ if n := r.Buffered(); n != 5 {
+ t.Fatalf("got %d bytes buffered in bufio.Reader; want 5 bytes", n)
+ }
+
+ // This is the second read of 0 bytes.
+ read, err = r.Read([]byte{})
+ if err != nil {
+ t.Fatalf("unexpected error: %v", err)
+ }
+ if read != 0 {
+ t.Fatalf("read %d bytes; want 0 bytes", read)
+ }
+}
+
+type writerWithReadFromError struct{}
+
+func (w writerWithReadFromError) ReadFrom(r io.Reader) (int64, error) {
+ return 0, errors.New("writerWithReadFromError error")
+}
+
+func (w writerWithReadFromError) Write(b []byte) (n int, err error) {
+ return 10, nil
+}
+
+func TestWriterReadFromMustSetUnderlyingError(t *testing.T) {
+ var wr = NewWriter(writerWithReadFromError{})
+ if _, err := wr.ReadFrom(strings.NewReader("test2")); err == nil {
+ t.Fatal("expected ReadFrom returns error, got nil")
+ }
+ if _, err := wr.Write([]byte("123")); err == nil {
+ t.Fatal("expected Write returns error, got nil")
+ }
+}
+
+type writeErrorOnlyWriter struct{}
+
+func (w writeErrorOnlyWriter) Write(p []byte) (n int, err error) {
+ return 0, errors.New("writeErrorOnlyWriter error")
+}
+
+// Ensure that previous Write errors are immediately returned
+// on any ReadFrom. See golang.org/issue/35194.
+func TestWriterReadFromMustReturnUnderlyingError(t *testing.T) {
+ var wr = NewWriter(writeErrorOnlyWriter{})
+ s := "test1"
+ wantBuffered := len(s)
+ if _, err := wr.WriteString(s); err != nil {
+ t.Fatalf("unexpected error: %v", err)
+ }
+ if err := wr.Flush(); err == nil {
+ t.Error("expected flush error, got nil")
+ }
+ if _, err := wr.ReadFrom(strings.NewReader("test2")); err == nil {
+ t.Fatal("expected error, got nil")
+ }
+ if buffered := wr.Buffered(); buffered != wantBuffered {
+ t.Fatalf("Buffered = %v; want %v", buffered, wantBuffered)
+ }
+}
+
+func BenchmarkReaderCopyOptimal(b *testing.B) {
+ // Optimal case is where the underlying reader implements io.WriterTo
+ srcBuf := bytes.NewBuffer(make([]byte, 8192))
+ src := NewReader(srcBuf)
+ dstBuf := new(bytes.Buffer)
+ dst := onlyWriter{dstBuf}
+ for i := 0; i < b.N; i++ {
+ srcBuf.Reset()
+ src.Reset(srcBuf)
+ dstBuf.Reset()
+ io.Copy(dst, src)
+ }
+}
+
+func BenchmarkReaderCopyUnoptimal(b *testing.B) {
+ // Unoptimal case is where the underlying reader doesn't implement io.WriterTo
+ srcBuf := bytes.NewBuffer(make([]byte, 8192))
+ src := NewReader(onlyReader{srcBuf})
+ dstBuf := new(bytes.Buffer)
+ dst := onlyWriter{dstBuf}
+ for i := 0; i < b.N; i++ {
+ srcBuf.Reset()
+ src.Reset(onlyReader{srcBuf})
+ dstBuf.Reset()
+ io.Copy(dst, src)
+ }
+}
+
+func BenchmarkReaderCopyNoWriteTo(b *testing.B) {
+ srcBuf := bytes.NewBuffer(make([]byte, 8192))
+ srcReader := NewReader(srcBuf)
+ src := onlyReader{srcReader}
+ dstBuf := new(bytes.Buffer)
+ dst := onlyWriter{dstBuf}
+ for i := 0; i < b.N; i++ {
+ srcBuf.Reset()
+ srcReader.Reset(srcBuf)
+ dstBuf.Reset()
+ io.Copy(dst, src)
+ }
+}
+
+func BenchmarkReaderWriteToOptimal(b *testing.B) {
+ const bufSize = 16 << 10
+ buf := make([]byte, bufSize)
+ r := bytes.NewReader(buf)
+ srcReader := NewReaderSize(onlyReader{r}, 1<<10)
+ if _, ok := io.Discard.(io.ReaderFrom); !ok {
+ b.Fatal("io.Discard doesn't support ReaderFrom")
+ }
+ for i := 0; i < b.N; i++ {
+ r.Seek(0, io.SeekStart)
+ srcReader.Reset(onlyReader{r})
+ n, err := srcReader.WriteTo(io.Discard)
+ if err != nil {
+ b.Fatal(err)
+ }
+ if n != bufSize {
+ b.Fatalf("n = %d; want %d", n, bufSize)
+ }
+ }
+}
+
+func BenchmarkReaderReadString(b *testing.B) {
+ r := strings.NewReader(" foo foo 42 42 42 42 42 42 42 42 4.2 4.2 4.2 4.2\n")
+ buf := NewReader(r)
+ b.ReportAllocs()
+ for i := 0; i < b.N; i++ {
+ r.Seek(0, io.SeekStart)
+ buf.Reset(r)
+
+ _, err := buf.ReadString('\n')
+ if err != nil {
+ b.Fatal(err)
+ }
+ }
+}
+
+func BenchmarkWriterCopyOptimal(b *testing.B) {
+ // Optimal case is where the underlying writer implements io.ReaderFrom
+ srcBuf := bytes.NewBuffer(make([]byte, 8192))
+ src := onlyReader{srcBuf}
+ dstBuf := new(bytes.Buffer)
+ dst := NewWriter(dstBuf)
+ for i := 0; i < b.N; i++ {
+ srcBuf.Reset()
+ dstBuf.Reset()
+ dst.Reset(dstBuf)
+ io.Copy(dst, src)
+ }
+}
+
+func BenchmarkWriterCopyUnoptimal(b *testing.B) {
+ srcBuf := bytes.NewBuffer(make([]byte, 8192))
+ src := onlyReader{srcBuf}
+ dstBuf := new(bytes.Buffer)
+ dst := NewWriter(onlyWriter{dstBuf})
+ for i := 0; i < b.N; i++ {
+ srcBuf.Reset()
+ dstBuf.Reset()
+ dst.Reset(onlyWriter{dstBuf})
+ io.Copy(dst, src)
+ }
+}
+
+func BenchmarkWriterCopyNoReadFrom(b *testing.B) {
+ srcBuf := bytes.NewBuffer(make([]byte, 8192))
+ src := onlyReader{srcBuf}
+ dstBuf := new(bytes.Buffer)
+ dstWriter := NewWriter(dstBuf)
+ dst := onlyWriter{dstWriter}
+ for i := 0; i < b.N; i++ {
+ srcBuf.Reset()
+ dstBuf.Reset()
+ dstWriter.Reset(dstBuf)
+ io.Copy(dst, src)
+ }
+}
+
+func BenchmarkReaderEmpty(b *testing.B) {
+ b.ReportAllocs()
+ str := strings.Repeat("x", 16<<10)
+ for i := 0; i < b.N; i++ {
+ br := NewReader(strings.NewReader(str))
+ n, err := io.Copy(io.Discard, br)
+ if err != nil {
+ b.Fatal(err)
+ }
+ if n != int64(len(str)) {
+ b.Fatal("wrong length")
+ }
+ }
+}
+
+func BenchmarkWriterEmpty(b *testing.B) {
+ b.ReportAllocs()
+ str := strings.Repeat("x", 1<<10)
+ bs := []byte(str)
+ for i := 0; i < b.N; i++ {
+ bw := NewWriter(io.Discard)
+ bw.Flush()
+ bw.WriteByte('a')
+ bw.Flush()
+ bw.WriteRune('B')
+ bw.Flush()
+ bw.Write(bs)
+ bw.Flush()
+ bw.WriteString(str)
+ bw.Flush()
+ }
+}
+
+func BenchmarkWriterFlush(b *testing.B) {
+ b.ReportAllocs()
+ bw := NewWriter(io.Discard)
+ str := strings.Repeat("x", 50)
+ for i := 0; i < b.N; i++ {
+ bw.WriteString(str)
+ bw.Flush()
+ }
+}
diff --git a/go/src/bufio/example_test.go b/go/src/bufio/example_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..7d4f0c1c28dce2d27f7d74b974e5f4746818d716
--- /dev/null
+++ b/go/src/bufio/example_test.go
@@ -0,0 +1,200 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bufio_test
+
+import (
+ "bufio"
+ "bytes"
+ "fmt"
+ "os"
+ "strconv"
+ "strings"
+)
+
+func ExampleWriter() {
+ w := bufio.NewWriter(os.Stdout)
+ fmt.Fprint(w, "Hello, ")
+ fmt.Fprint(w, "world!")
+ w.Flush() // Don't forget to flush!
+ // Output: Hello, world!
+}
+
+func ExampleWriter_AvailableBuffer() {
+ w := bufio.NewWriter(os.Stdout)
+ for _, i := range []int64{1, 2, 3, 4} {
+ b := w.AvailableBuffer()
+ b = strconv.AppendInt(b, i, 10)
+ b = append(b, ' ')
+ w.Write(b)
+ }
+ w.Flush()
+ // Output: 1 2 3 4
+}
+
+// ExampleWriter_ReadFrom demonstrates how to use the ReadFrom method of Writer.
+func ExampleWriter_ReadFrom() {
+ var buf bytes.Buffer
+ writer := bufio.NewWriter(&buf)
+
+ data := "Hello, world!\nThis is a ReadFrom example."
+ reader := strings.NewReader(data)
+
+ n, err := writer.ReadFrom(reader)
+ if err != nil {
+ fmt.Println("ReadFrom Error:", err)
+ return
+ }
+
+ if err = writer.Flush(); err != nil {
+ fmt.Println("Flush Error:", err)
+ return
+ }
+
+ fmt.Println("Bytes written:", n)
+ fmt.Println("Buffer contents:", buf.String())
+ // Output:
+ // Bytes written: 41
+ // Buffer contents: Hello, world!
+ // This is a ReadFrom example.
+}
+
+// The simplest use of a Scanner, to read standard input as a set of lines.
+func ExampleScanner_lines() {
+ scanner := bufio.NewScanner(os.Stdin)
+ for scanner.Scan() {
+ fmt.Println(scanner.Text()) // Println will add back the final '\n'
+ }
+ if err := scanner.Err(); err != nil {
+ fmt.Fprintln(os.Stderr, "reading standard input:", err)
+ }
+}
+
+// Return the most recent call to Scan as a []byte.
+func ExampleScanner_Bytes() {
+ scanner := bufio.NewScanner(strings.NewReader("gopher"))
+ for scanner.Scan() {
+ fmt.Println(len(scanner.Bytes()) == 6)
+ }
+ if err := scanner.Err(); err != nil {
+ fmt.Fprintln(os.Stderr, "shouldn't see an error scanning a string")
+ }
+ // Output:
+ // true
+}
+
+// Use a Scanner to implement a simple word-count utility by scanning the
+// input as a sequence of space-delimited tokens.
+func ExampleScanner_words() {
+ // An artificial input source.
+ const input = "Now is the winter of our discontent,\nMade glorious summer by this sun of York.\n"
+ scanner := bufio.NewScanner(strings.NewReader(input))
+ // Set the split function for the scanning operation.
+ scanner.Split(bufio.ScanWords)
+ // Count the words.
+ count := 0
+ for scanner.Scan() {
+ count++
+ }
+ if err := scanner.Err(); err != nil {
+ fmt.Fprintln(os.Stderr, "reading input:", err)
+ }
+ fmt.Printf("%d\n", count)
+ // Output: 15
+}
+
+// Use a Scanner with a custom split function (built by wrapping ScanWords) to validate
+// 32-bit decimal input.
+func ExampleScanner_custom() {
+ // An artificial input source.
+ const input = "1234 5678 1234567901234567890"
+ scanner := bufio.NewScanner(strings.NewReader(input))
+ // Create a custom split function by wrapping the existing ScanWords function.
+ split := func(data []byte, atEOF bool) (advance int, token []byte, err error) {
+ advance, token, err = bufio.ScanWords(data, atEOF)
+ if err == nil && token != nil {
+ _, err = strconv.ParseInt(string(token), 10, 32)
+ }
+ return
+ }
+ // Set the split function for the scanning operation.
+ scanner.Split(split)
+ // Validate the input
+ for scanner.Scan() {
+ fmt.Printf("%s\n", scanner.Text())
+ }
+
+ if err := scanner.Err(); err != nil {
+ fmt.Printf("Invalid input: %s", err)
+ }
+ // Output:
+ // 1234
+ // 5678
+ // Invalid input: strconv.ParseInt: parsing "1234567901234567890": value out of range
+}
+
+// Use a Scanner with a custom split function to parse a comma-separated
+// list with an empty final value.
+func ExampleScanner_emptyFinalToken() {
+ // Comma-separated list; last entry is empty.
+ const input = "1,2,3,4,"
+ scanner := bufio.NewScanner(strings.NewReader(input))
+ // Define a split function that separates on commas.
+ onComma := func(data []byte, atEOF bool) (advance int, token []byte, err error) {
+ for i := 0; i < len(data); i++ {
+ if data[i] == ',' {
+ return i + 1, data[:i], nil
+ }
+ }
+ if !atEOF {
+ return 0, nil, nil
+ }
+ // There is one final token to be delivered, which may be the empty string.
+ // Returning bufio.ErrFinalToken here tells Scan there are no more tokens after this
+ // but does not trigger an error to be returned from Scan itself.
+ return 0, data, bufio.ErrFinalToken
+ }
+ scanner.Split(onComma)
+ // Scan.
+ for scanner.Scan() {
+ fmt.Printf("%q ", scanner.Text())
+ }
+ if err := scanner.Err(); err != nil {
+ fmt.Fprintln(os.Stderr, "reading input:", err)
+ }
+ // Output: "1" "2" "3" "4" ""
+}
+
+// Use a Scanner with a custom split function to parse a comma-separated
+// list with an empty final value but stops at the token "STOP".
+func ExampleScanner_earlyStop() {
+ onComma := func(data []byte, atEOF bool) (advance int, token []byte, err error) {
+ i := bytes.IndexByte(data, ',')
+ if i == -1 {
+ if !atEOF {
+ return 0, nil, nil
+ }
+ // If we have reached the end, return the last token.
+ return 0, data, bufio.ErrFinalToken
+ }
+ // If the token is "STOP", stop the scanning and ignore the rest.
+ if string(data[:i]) == "STOP" {
+ return i + 1, nil, bufio.ErrFinalToken
+ }
+ // Otherwise, return the token before the comma.
+ return i + 1, data[:i], nil
+ }
+ const input = "1,2,STOP,4,"
+ scanner := bufio.NewScanner(strings.NewReader(input))
+ scanner.Split(onComma)
+ for scanner.Scan() {
+ fmt.Printf("Got a token %q\n", scanner.Text())
+ }
+ if err := scanner.Err(); err != nil {
+ fmt.Fprintln(os.Stderr, "reading input:", err)
+ }
+ // Output:
+ // Got a token "1"
+ // Got a token "2"
+}
diff --git a/go/src/bufio/export_test.go b/go/src/bufio/export_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..1667f01a841e07cba04c62e8cf7da7ab3593ca2b
--- /dev/null
+++ b/go/src/bufio/export_test.go
@@ -0,0 +1,29 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bufio
+
+// Exported for testing only.
+import (
+ "unicode/utf8"
+)
+
+var IsSpace = isSpace
+
+const DefaultBufSize = defaultBufSize
+
+func (s *Scanner) MaxTokenSize(n int) {
+ if n < utf8.UTFMax || n > 1e9 {
+ panic("bad max token size")
+ }
+ if n < len(s.buf) {
+ s.buf = make([]byte, n)
+ }
+ s.maxTokenSize = n
+}
+
+// ErrOrEOF is like Err, but returns EOF. Used to test a corner case.
+func (s *Scanner) ErrOrEOF() error {
+ return s.err
+}
diff --git a/go/src/bufio/net_test.go b/go/src/bufio/net_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..d3b47e4cb99a39264b3f26ecd5ac1cdd3bc7b188
--- /dev/null
+++ b/go/src/bufio/net_test.go
@@ -0,0 +1,96 @@
+// Copyright 2025 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+package bufio_test
+
+import (
+ "bufio"
+ "io"
+ "net"
+ "path/filepath"
+ "strings"
+ "sync"
+ "testing"
+)
+
+// TestCopyUnixpacket tests that we can use bufio when copying
+// across a unixpacket socket. This used to fail due to an unnecessary
+// empty Write call that was interpreted as an EOF.
+func TestCopyUnixpacket(t *testing.T) {
+ tmpDir := t.TempDir()
+ socket := filepath.Join(tmpDir, "unixsock")
+
+ // Start a unixpacket server.
+ addr := &net.UnixAddr{
+ Name: socket,
+ Net: "unixpacket",
+ }
+ server, err := net.ListenUnix("unixpacket", addr)
+ if err != nil {
+ t.Skipf("skipping test because opening a unixpacket socket failed: %v", err)
+ }
+
+ // Start a goroutine for the server to accept one connection
+ // and read all the data sent on the connection,
+ // reporting the number of bytes read on ch.
+ ch := make(chan int, 1)
+ var wg sync.WaitGroup
+ wg.Add(1)
+ go func() {
+ defer wg.Done()
+
+ tot := 0
+ defer func() {
+ ch <- tot
+ }()
+
+ serverConn, err := server.Accept()
+ if err != nil {
+ t.Error(err)
+ return
+ }
+
+ buf := make([]byte, 1024)
+ for {
+ n, err := serverConn.Read(buf)
+ tot += n
+ if err == io.EOF {
+ return
+ }
+ if err != nil {
+ t.Error(err)
+ return
+ }
+ }
+ }()
+
+ clientConn, err := net.DialUnix("unixpacket", nil, addr)
+ if err != nil {
+ // Leaves the server goroutine hanging. Oh well.
+ t.Fatal(err)
+ }
+
+ defer wg.Wait()
+ defer clientConn.Close()
+
+ const data = "data"
+ r := bufio.NewReader(strings.NewReader(data))
+ n, err := io.Copy(clientConn, r)
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ if n != int64(len(data)) {
+ t.Errorf("io.Copy returned %d, want %d", n, len(data))
+ }
+
+ clientConn.Close()
+ tot := <-ch
+
+ if tot != len(data) {
+ t.Errorf("server read %d, want %d", tot, len(data))
+ }
+}
diff --git a/go/src/bufio/scan.go b/go/src/bufio/scan.go
new file mode 100644
index 0000000000000000000000000000000000000000..1a0a3907c9eb8584ebbafa5bbd9dc34511080691
--- /dev/null
+++ b/go/src/bufio/scan.go
@@ -0,0 +1,427 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bufio
+
+import (
+ "bytes"
+ "errors"
+ "io"
+ "unicode/utf8"
+)
+
+// Scanner provides a convenient interface for reading data such as
+// a file of newline-delimited lines of text. Successive calls to
+// the [Scanner.Scan] method will step through the 'tokens' of a file, skipping
+// the bytes between the tokens. The specification of a token is
+// defined by a split function of type [SplitFunc]; the default split
+// function breaks the input into lines with line termination stripped. [Scanner.Split]
+// functions are defined in this package for scanning a file into
+// lines, bytes, UTF-8-encoded runes, and space-delimited words. The
+// client may instead provide a custom split function.
+//
+// Scanning stops unrecoverably at EOF, the first I/O error, or a token too
+// large to fit in the [Scanner.Buffer]. When a scan stops, the reader may have
+// advanced arbitrarily far past the last token. Programs that need more
+// control over error handling or large tokens, or must run sequential scans
+// on a reader, should use [bufio.Reader] instead.
+type Scanner struct {
+ r io.Reader // The reader provided by the client.
+ split SplitFunc // The function to split the tokens.
+ maxTokenSize int // Maximum size of a token; modified by tests.
+ token []byte // Last token returned by split.
+ buf []byte // Buffer used as argument to split.
+ start int // First non-processed byte in buf.
+ end int // End of data in buf.
+ err error // Sticky error.
+ empties int // Count of successive empty tokens.
+ scanCalled bool // Scan has been called; buffer is in use.
+ done bool // Scan has finished.
+}
+
+// SplitFunc is the signature of the split function used to tokenize the
+// input. The arguments are an initial substring of the remaining unprocessed
+// data and a flag, atEOF, that reports whether the [Reader] has no more data
+// to give. The return values are the number of bytes to advance the input
+// and the next token to return to the user, if any, plus an error, if any.
+//
+// Scanning stops if the function returns an error, in which case some of
+// the input may be discarded. If that error is [ErrFinalToken], scanning
+// stops with no error. A non-nil token delivered with [ErrFinalToken]
+// will be the last token, and a nil token with [ErrFinalToken]
+// immediately stops the scanning.
+//
+// Otherwise, the [Scanner] advances the input. If the token is not nil,
+// the [Scanner] returns it to the user. If the token is nil, the
+// Scanner reads more data and continues scanning; if there is no more
+// data--if atEOF was true--the [Scanner] returns. If the data does not
+// yet hold a complete token, for instance if it has no newline while
+// scanning lines, a [SplitFunc] can return (0, nil, nil) to signal the
+// [Scanner] to read more data into the slice and try again with a
+// longer slice starting at the same point in the input.
+//
+// The function is never called with an empty data slice unless atEOF
+// is true. If atEOF is true, however, data may be non-empty and,
+// as always, holds unprocessed text.
+type SplitFunc func(data []byte, atEOF bool) (advance int, token []byte, err error)
+
+// Errors returned by Scanner.
+var (
+ ErrTooLong = errors.New("bufio.Scanner: token too long")
+ ErrNegativeAdvance = errors.New("bufio.Scanner: SplitFunc returns negative advance count")
+ ErrAdvanceTooFar = errors.New("bufio.Scanner: SplitFunc returns advance count beyond input")
+ ErrBadReadCount = errors.New("bufio.Scanner: Read returned impossible count")
+)
+
+const (
+ // MaxScanTokenSize is the maximum size used to buffer a token
+ // unless the user provides an explicit buffer with [Scanner.Buffer].
+ // The actual maximum token size may be smaller as the buffer
+ // may need to include, for instance, a newline.
+ MaxScanTokenSize = 64 * 1024
+
+ startBufSize = 4096 // Size of initial allocation for buffer.
+)
+
+// NewScanner returns a new [Scanner] to read from r.
+// The split function defaults to [ScanLines].
+func NewScanner(r io.Reader) *Scanner {
+ return &Scanner{
+ r: r,
+ split: ScanLines,
+ maxTokenSize: MaxScanTokenSize,
+ }
+}
+
+// Err returns the first non-EOF error that was encountered by the [Scanner].
+func (s *Scanner) Err() error {
+ if s.err == io.EOF {
+ return nil
+ }
+ return s.err
+}
+
+// Bytes returns the most recent token generated by a call to [Scanner.Scan].
+// The underlying array may point to data that will be overwritten
+// by a subsequent call to Scan. It does no allocation.
+func (s *Scanner) Bytes() []byte {
+ return s.token
+}
+
+// Text returns the most recent token generated by a call to [Scanner.Scan]
+// as a newly allocated string holding its bytes.
+func (s *Scanner) Text() string {
+ return string(s.token)
+}
+
+// ErrFinalToken is a special sentinel error value. It is intended to be
+// returned by a Split function to indicate that the scanning should stop
+// with no error. If the token being delivered with this error is not nil,
+// the token is the last token.
+//
+// The value is useful to stop processing early or when it is necessary to
+// deliver a final empty token (which is different from a nil token).
+// One could achieve the same behavior with a custom error value but
+// providing one here is tidier.
+// See the emptyFinalToken example for a use of this value.
+var ErrFinalToken = errors.New("final token")
+
+// Scan advances the [Scanner] to the next token, which will then be
+// available through the [Scanner.Bytes] or [Scanner.Text] method. It returns false when
+// there are no more tokens, either by reaching the end of the input or an error.
+// After Scan returns false, the [Scanner.Err] method will return any error that
+// occurred during scanning, except that if it was [io.EOF], [Scanner.Err]
+// will return nil.
+// Scan panics if the split function returns too many empty
+// tokens without advancing the input. This is a common error mode for
+// scanners.
+func (s *Scanner) Scan() bool {
+ if s.done {
+ return false
+ }
+ s.scanCalled = true
+ // Loop until we have a token.
+ for {
+ // See if we can get a token with what we already have.
+ // If we've run out of data but have an error, give the split function
+ // a chance to recover any remaining, possibly empty token.
+ if s.end > s.start || s.err != nil {
+ advance, token, err := s.split(s.buf[s.start:s.end], s.err != nil)
+ if err != nil {
+ if err == ErrFinalToken {
+ s.token = token
+ s.done = true
+ // When token is not nil, it means the scanning stops
+ // with a trailing token, and thus the return value
+ // should be true to indicate the existence of the token.
+ return token != nil
+ }
+ s.setErr(err)
+ return false
+ }
+ if !s.advance(advance) {
+ return false
+ }
+ s.token = token
+ if token != nil {
+ if s.err == nil || advance > 0 {
+ s.empties = 0
+ } else {
+ // Returning tokens not advancing input at EOF.
+ s.empties++
+ if s.empties > maxConsecutiveEmptyReads {
+ panic("bufio.Scan: too many empty tokens without progressing")
+ }
+ }
+ return true
+ }
+ }
+ // We cannot generate a token with what we are holding.
+ // If we've already hit EOF or an I/O error, we are done.
+ if s.err != nil {
+ // Shut it down.
+ s.start = 0
+ s.end = 0
+ return false
+ }
+ // Must read more data.
+ // First, shift data to beginning of buffer if there's lots of empty space
+ // or space is needed.
+ if s.start > 0 && (s.end == len(s.buf) || s.start > len(s.buf)/2) {
+ copy(s.buf, s.buf[s.start:s.end])
+ s.end -= s.start
+ s.start = 0
+ }
+ // Is the buffer full? If so, resize.
+ if s.end == len(s.buf) {
+ // Guarantee no overflow in the multiplication below.
+ const maxInt = int(^uint(0) >> 1)
+ if len(s.buf) >= s.maxTokenSize || len(s.buf) > maxInt/2 {
+ s.setErr(ErrTooLong)
+ return false
+ }
+ newSize := len(s.buf) * 2
+ if newSize == 0 {
+ newSize = startBufSize
+ }
+ newSize = min(newSize, s.maxTokenSize)
+ newBuf := make([]byte, newSize)
+ copy(newBuf, s.buf[s.start:s.end])
+ s.buf = newBuf
+ s.end -= s.start
+ s.start = 0
+ }
+ // Finally we can read some input. Make sure we don't get stuck with
+ // a misbehaving Reader. Officially we don't need to do this, but let's
+ // be extra careful: Scanner is for safe, simple jobs.
+ for loop := 0; ; {
+ n, err := s.r.Read(s.buf[s.end:len(s.buf)])
+ if n < 0 || len(s.buf)-s.end < n {
+ s.setErr(ErrBadReadCount)
+ break
+ }
+ s.end += n
+ if err != nil {
+ s.setErr(err)
+ break
+ }
+ if n > 0 {
+ s.empties = 0
+ break
+ }
+ loop++
+ if loop > maxConsecutiveEmptyReads {
+ s.setErr(io.ErrNoProgress)
+ break
+ }
+ }
+ }
+}
+
+// advance consumes n bytes of the buffer. It reports whether the advance was legal.
+func (s *Scanner) advance(n int) bool {
+ if n < 0 {
+ s.setErr(ErrNegativeAdvance)
+ return false
+ }
+ if n > s.end-s.start {
+ s.setErr(ErrAdvanceTooFar)
+ return false
+ }
+ s.start += n
+ return true
+}
+
+// setErr records the first error encountered.
+func (s *Scanner) setErr(err error) {
+ if s.err == nil || s.err == io.EOF {
+ s.err = err
+ }
+}
+
+// Buffer controls memory allocation by the Scanner.
+// It sets the initial buffer to use when scanning
+// and the maximum size of buffer that may be allocated during scanning.
+// The contents of the buffer are ignored.
+//
+// The maximum token size must be less than the larger of max and cap(buf).
+// If max <= cap(buf), [Scanner.Scan] will use this buffer only and do no allocation.
+//
+// By default, [Scanner.Scan] uses an internal buffer and sets the
+// maximum token size to [MaxScanTokenSize].
+//
+// Buffer panics if it is called after scanning has started.
+func (s *Scanner) Buffer(buf []byte, max int) {
+ if s.scanCalled {
+ panic("Buffer called after Scan")
+ }
+ s.buf = buf[0:cap(buf)]
+ s.maxTokenSize = max
+}
+
+// Split sets the split function for the [Scanner].
+// The default split function is [ScanLines].
+//
+// Split panics if it is called after scanning has started.
+func (s *Scanner) Split(split SplitFunc) {
+ if s.scanCalled {
+ panic("Split called after Scan")
+ }
+ s.split = split
+}
+
+// Split functions
+
+// ScanBytes is a split function for a [Scanner] that returns each byte as a token.
+func ScanBytes(data []byte, atEOF bool) (advance int, token []byte, err error) {
+ if atEOF && len(data) == 0 {
+ return 0, nil, nil
+ }
+ return 1, data[0:1], nil
+}
+
+var errorRune = []byte(string(utf8.RuneError))
+
+// ScanRunes is a split function for a [Scanner] that returns each
+// UTF-8-encoded rune as a token. The sequence of runes returned is
+// equivalent to that from a range loop over the input as a string, which
+// means that erroneous UTF-8 encodings translate to U+FFFD = "\xef\xbf\xbd".
+// Because of the Scan interface, this makes it impossible for the client to
+// distinguish correctly encoded replacement runes from encoding errors.
+func ScanRunes(data []byte, atEOF bool) (advance int, token []byte, err error) {
+ if atEOF && len(data) == 0 {
+ return 0, nil, nil
+ }
+
+ // Fast path 1: ASCII.
+ if data[0] < utf8.RuneSelf {
+ return 1, data[0:1], nil
+ }
+
+ // Fast path 2: Correct UTF-8 decode without error.
+ _, width := utf8.DecodeRune(data)
+ if width > 1 {
+ // It's a valid encoding. Width cannot be one for a correctly encoded
+ // non-ASCII rune.
+ return width, data[0:width], nil
+ }
+
+ // We know it's an error: we have width==1 and implicitly r==utf8.RuneError.
+ // Is the error because there wasn't a full rune to be decoded?
+ // FullRune distinguishes correctly between erroneous and incomplete encodings.
+ if !atEOF && !utf8.FullRune(data) {
+ // Incomplete; get more bytes.
+ return 0, nil, nil
+ }
+
+ // We have a real UTF-8 encoding error. Return a properly encoded error rune
+ // but advance only one byte. This matches the behavior of a range loop over
+ // an incorrectly encoded string.
+ return 1, errorRune, nil
+}
+
+// dropCR drops a terminal \r from the data.
+func dropCR(data []byte) []byte {
+ if len(data) > 0 && data[len(data)-1] == '\r' {
+ return data[0 : len(data)-1]
+ }
+ return data
+}
+
+// ScanLines is a split function for a [Scanner] that returns each line of
+// text, stripped of any trailing end-of-line marker. The returned line may
+// be empty. The end-of-line marker is one optional carriage return followed
+// by one mandatory newline. In regular expression notation, it is `\r?\n`.
+// The last non-empty line of input will be returned even if it has no
+// newline.
+func ScanLines(data []byte, atEOF bool) (advance int, token []byte, err error) {
+ if atEOF && len(data) == 0 {
+ return 0, nil, nil
+ }
+ if i := bytes.IndexByte(data, '\n'); i >= 0 {
+ // We have a full newline-terminated line.
+ return i + 1, dropCR(data[0:i]), nil
+ }
+ // If we're at EOF, we have a final, non-terminated line. Return it.
+ if atEOF {
+ return len(data), dropCR(data), nil
+ }
+ // Request more data.
+ return 0, nil, nil
+}
+
+// isSpace reports whether the character is a Unicode white space character.
+// We avoid dependency on the unicode package, but check validity of the implementation
+// in the tests.
+func isSpace(r rune) bool {
+ if r <= '\u00FF' {
+ // Obvious ASCII ones: \t through \r plus space. Plus two Latin-1 oddballs.
+ switch r {
+ case ' ', '\t', '\n', '\v', '\f', '\r':
+ return true
+ case '\u0085', '\u00A0':
+ return true
+ }
+ return false
+ }
+ // High-valued ones.
+ if '\u2000' <= r && r <= '\u200a' {
+ return true
+ }
+ switch r {
+ case '\u1680', '\u2028', '\u2029', '\u202f', '\u205f', '\u3000':
+ return true
+ }
+ return false
+}
+
+// ScanWords is a split function for a [Scanner] that returns each
+// space-separated word of text, with surrounding spaces deleted. It will
+// never return an empty string. The definition of space is set by
+// unicode.IsSpace.
+func ScanWords(data []byte, atEOF bool) (advance int, token []byte, err error) {
+ // Skip leading spaces.
+ start := 0
+ for width := 0; start < len(data); start += width {
+ var r rune
+ r, width = utf8.DecodeRune(data[start:])
+ if !isSpace(r) {
+ break
+ }
+ }
+ // Scan until space, marking end of word.
+ for width, i := 0, start; i < len(data); i += width {
+ var r rune
+ r, width = utf8.DecodeRune(data[i:])
+ if isSpace(r) {
+ return i + width, data[start:i], nil
+ }
+ }
+ // If we're at EOF, we have a final, non-empty, non-terminated word. Return it.
+ if atEOF && len(data) > start {
+ return len(data), data[start:], nil
+ }
+ // Request more data.
+ return start, nil, nil
+}
diff --git a/go/src/bufio/scan_test.go b/go/src/bufio/scan_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..6b64f7ba9c5d896356a4a3a7e2646de30e6837e0
--- /dev/null
+++ b/go/src/bufio/scan_test.go
@@ -0,0 +1,596 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bufio_test
+
+import (
+ . "bufio"
+ "bytes"
+ "errors"
+ "io"
+ "strings"
+ "testing"
+ "unicode"
+ "unicode/utf8"
+)
+
+const smallMaxTokenSize = 256 // Much smaller for more efficient testing.
+
+// Test white space table matches the Unicode definition.
+func TestSpace(t *testing.T) {
+ for r := rune(0); r <= utf8.MaxRune; r++ {
+ if IsSpace(r) != unicode.IsSpace(r) {
+ t.Fatalf("white space property disagrees: %#U should be %t", r, unicode.IsSpace(r))
+ }
+ }
+}
+
+var scanTests = []string{
+ "",
+ "a",
+ "¼",
+ "☹",
+ "\x81", // UTF-8 error
+ "\uFFFD", // correctly encoded RuneError
+ "abcdefgh",
+ "abc def\n\t\tgh ",
+ "abc¼☹\x81\uFFFD日本語\x82abc",
+}
+
+func TestScanByte(t *testing.T) {
+ for n, test := range scanTests {
+ buf := strings.NewReader(test)
+ s := NewScanner(buf)
+ s.Split(ScanBytes)
+ var i int
+ for i = 0; s.Scan(); i++ {
+ if b := s.Bytes(); len(b) != 1 || b[0] != test[i] {
+ t.Errorf("#%d: %d: expected %q got %q", n, i, test, b)
+ }
+ }
+ if i != len(test) {
+ t.Errorf("#%d: termination expected at %d; got %d", n, len(test), i)
+ }
+ err := s.Err()
+ if err != nil {
+ t.Errorf("#%d: %v", n, err)
+ }
+ }
+}
+
+// Test that the rune splitter returns same sequence of runes (not bytes) as for range string.
+func TestScanRune(t *testing.T) {
+ for n, test := range scanTests {
+ buf := strings.NewReader(test)
+ s := NewScanner(buf)
+ s.Split(ScanRunes)
+ var i, runeCount int
+ var expect rune
+ // Use a string range loop to validate the sequence of runes.
+ for i, expect = range test {
+ if !s.Scan() {
+ break
+ }
+ runeCount++
+ got, _ := utf8.DecodeRune(s.Bytes())
+ if got != expect {
+ t.Errorf("#%d: %d: expected %q got %q", n, i, expect, got)
+ }
+ }
+ if s.Scan() {
+ t.Errorf("#%d: scan ran too long, got %q", n, s.Text())
+ }
+ testRuneCount := utf8.RuneCountInString(test)
+ if runeCount != testRuneCount {
+ t.Errorf("#%d: termination expected at %d; got %d", n, testRuneCount, runeCount)
+ }
+ err := s.Err()
+ if err != nil {
+ t.Errorf("#%d: %v", n, err)
+ }
+ }
+}
+
+var wordScanTests = []string{
+ "",
+ " ",
+ "\n",
+ "a",
+ " a ",
+ "abc def",
+ " abc def ",
+ " abc\tdef\nghi\rjkl\fmno\vpqr\u0085stu\u00a0\n",
+}
+
+// Test that the word splitter returns the same data as strings.Fields.
+func TestScanWords(t *testing.T) {
+ for n, test := range wordScanTests {
+ buf := strings.NewReader(test)
+ s := NewScanner(buf)
+ s.Split(ScanWords)
+ words := strings.Fields(test)
+ var wordCount int
+ for wordCount = 0; wordCount < len(words); wordCount++ {
+ if !s.Scan() {
+ break
+ }
+ got := s.Text()
+ if got != words[wordCount] {
+ t.Errorf("#%d: %d: expected %q got %q", n, wordCount, words[wordCount], got)
+ }
+ }
+ if s.Scan() {
+ t.Errorf("#%d: scan ran too long, got %q", n, s.Text())
+ }
+ if wordCount != len(words) {
+ t.Errorf("#%d: termination expected at %d; got %d", n, len(words), wordCount)
+ }
+ err := s.Err()
+ if err != nil {
+ t.Errorf("#%d: %v", n, err)
+ }
+ }
+}
+
+// slowReader is a reader that returns only a few bytes at a time, to test the incremental
+// reads in Scanner.Scan.
+type slowReader struct {
+ max int
+ buf io.Reader
+}
+
+func (sr *slowReader) Read(p []byte) (n int, err error) {
+ if len(p) > sr.max {
+ p = p[0:sr.max]
+ }
+ return sr.buf.Read(p)
+}
+
+// genLine writes to buf a predictable but non-trivial line of text of length
+// n, including the terminal newline and an occasional carriage return.
+// If addNewline is false, the \r and \n are not emitted.
+func genLine(buf *bytes.Buffer, lineNum, n int, addNewline bool) {
+ buf.Reset()
+ doCR := lineNum%5 == 0
+ if doCR {
+ n--
+ }
+ for i := 0; i < n-1; i++ { // Stop early for \n.
+ c := 'a' + byte(lineNum+i)
+ if c == '\n' || c == '\r' { // Don't confuse us.
+ c = 'N'
+ }
+ buf.WriteByte(c)
+ }
+ if addNewline {
+ if doCR {
+ buf.WriteByte('\r')
+ }
+ buf.WriteByte('\n')
+ }
+}
+
+// Test the line splitter, including some carriage returns but no long lines.
+func TestScanLongLines(t *testing.T) {
+ // Build a buffer of lots of line lengths up to but not exceeding smallMaxTokenSize.
+ tmp := new(bytes.Buffer)
+ buf := new(bytes.Buffer)
+ lineNum := 0
+ j := 0
+ for i := 0; i < 2*smallMaxTokenSize; i++ {
+ genLine(tmp, lineNum, j, true)
+ if j < smallMaxTokenSize {
+ j++
+ } else {
+ j--
+ }
+ buf.Write(tmp.Bytes())
+ lineNum++
+ }
+ s := NewScanner(&slowReader{1, buf})
+ s.Split(ScanLines)
+ s.MaxTokenSize(smallMaxTokenSize)
+ j = 0
+ for lineNum := 0; s.Scan(); lineNum++ {
+ genLine(tmp, lineNum, j, false)
+ if j < smallMaxTokenSize {
+ j++
+ } else {
+ j--
+ }
+ line := tmp.String() // We use the string-valued token here, for variety.
+ if s.Text() != line {
+ t.Errorf("%d: bad line: %d %d\n%.100q\n%.100q\n", lineNum, len(s.Bytes()), len(line), s.Text(), line)
+ }
+ }
+ err := s.Err()
+ if err != nil {
+ t.Fatal(err)
+ }
+}
+
+// Test that the line splitter errors out on a long line.
+func TestScanLineTooLong(t *testing.T) {
+ const smallMaxTokenSize = 256 // Much smaller for more efficient testing.
+ // Build a buffer of lots of line lengths up to but not exceeding smallMaxTokenSize.
+ tmp := new(bytes.Buffer)
+ buf := new(bytes.Buffer)
+ lineNum := 0
+ j := 0
+ for i := 0; i < 2*smallMaxTokenSize; i++ {
+ genLine(tmp, lineNum, j, true)
+ j++
+ buf.Write(tmp.Bytes())
+ lineNum++
+ }
+ s := NewScanner(&slowReader{3, buf})
+ s.Split(ScanLines)
+ s.MaxTokenSize(smallMaxTokenSize)
+ j = 0
+ for lineNum := 0; s.Scan(); lineNum++ {
+ genLine(tmp, lineNum, j, false)
+ if j < smallMaxTokenSize {
+ j++
+ } else {
+ j--
+ }
+ line := tmp.Bytes()
+ if !bytes.Equal(s.Bytes(), line) {
+ t.Errorf("%d: bad line: %d %d\n%.100q\n%.100q\n", lineNum, len(s.Bytes()), len(line), s.Bytes(), line)
+ }
+ }
+ err := s.Err()
+ if err != ErrTooLong {
+ t.Fatalf("expected ErrTooLong; got %s", err)
+ }
+}
+
+// Test that the line splitter handles a final line without a newline.
+func testNoNewline(text string, lines []string, t *testing.T) {
+ buf := strings.NewReader(text)
+ s := NewScanner(&slowReader{7, buf})
+ s.Split(ScanLines)
+ for lineNum := 0; s.Scan(); lineNum++ {
+ line := lines[lineNum]
+ if s.Text() != line {
+ t.Errorf("%d: bad line: %d %d\n%.100q\n%.100q\n", lineNum, len(s.Bytes()), len(line), s.Bytes(), line)
+ }
+ }
+ err := s.Err()
+ if err != nil {
+ t.Fatal(err)
+ }
+}
+
+// Test that the line splitter handles a final line without a newline.
+func TestScanLineNoNewline(t *testing.T) {
+ const text = "abcdefghijklmn\nopqrstuvwxyz"
+ lines := []string{
+ "abcdefghijklmn",
+ "opqrstuvwxyz",
+ }
+ testNoNewline(text, lines, t)
+}
+
+// Test that the line splitter handles a final line with a carriage return but no newline.
+func TestScanLineReturnButNoNewline(t *testing.T) {
+ const text = "abcdefghijklmn\nopqrstuvwxyz\r"
+ lines := []string{
+ "abcdefghijklmn",
+ "opqrstuvwxyz",
+ }
+ testNoNewline(text, lines, t)
+}
+
+// Test that the line splitter handles a final empty line.
+func TestScanLineEmptyFinalLine(t *testing.T) {
+ const text = "abcdefghijklmn\nopqrstuvwxyz\n\n"
+ lines := []string{
+ "abcdefghijklmn",
+ "opqrstuvwxyz",
+ "",
+ }
+ testNoNewline(text, lines, t)
+}
+
+// Test that the line splitter handles a final empty line with a carriage return but no newline.
+func TestScanLineEmptyFinalLineWithCR(t *testing.T) {
+ const text = "abcdefghijklmn\nopqrstuvwxyz\n\r"
+ lines := []string{
+ "abcdefghijklmn",
+ "opqrstuvwxyz",
+ "",
+ }
+ testNoNewline(text, lines, t)
+}
+
+var testError = errors.New("testError")
+
+// Test the correct error is returned when the split function errors out.
+func TestSplitError(t *testing.T) {
+ // Create a split function that delivers a little data, then a predictable error.
+ numSplits := 0
+ const okCount = 7
+ errorSplit := func(data []byte, atEOF bool) (advance int, token []byte, err error) {
+ if atEOF {
+ panic("didn't get enough data")
+ }
+ if numSplits >= okCount {
+ return 0, nil, testError
+ }
+ numSplits++
+ return 1, data[0:1], nil
+ }
+ // Read the data.
+ const text = "abcdefghijklmnopqrstuvwxyz"
+ buf := strings.NewReader(text)
+ s := NewScanner(&slowReader{1, buf})
+ s.Split(errorSplit)
+ var i int
+ for i = 0; s.Scan(); i++ {
+ if len(s.Bytes()) != 1 || text[i] != s.Bytes()[0] {
+ t.Errorf("#%d: expected %q got %q", i, text[i], s.Bytes()[0])
+ }
+ }
+ // Check correct termination location and error.
+ if i != okCount {
+ t.Errorf("unexpected termination; expected %d tokens got %d", okCount, i)
+ }
+ err := s.Err()
+ if err != testError {
+ t.Fatalf("expected %q got %v", testError, err)
+ }
+}
+
+// Test that an EOF is overridden by a user-generated scan error.
+func TestErrAtEOF(t *testing.T) {
+ s := NewScanner(strings.NewReader("1 2 33"))
+ // This splitter will fail on last entry, after s.err==EOF.
+ split := func(data []byte, atEOF bool) (advance int, token []byte, err error) {
+ advance, token, err = ScanWords(data, atEOF)
+ if len(token) > 1 {
+ if s.ErrOrEOF() != io.EOF {
+ t.Fatal("not testing EOF")
+ }
+ err = testError
+ }
+ return
+ }
+ s.Split(split)
+ for s.Scan() {
+ }
+ if s.Err() != testError {
+ t.Fatal("wrong error:", s.Err())
+ }
+}
+
+// Test for issue 5268.
+type alwaysError struct{}
+
+func (alwaysError) Read(p []byte) (int, error) {
+ return 0, io.ErrUnexpectedEOF
+}
+
+func TestNonEOFWithEmptyRead(t *testing.T) {
+ scanner := NewScanner(alwaysError{})
+ for scanner.Scan() {
+ t.Fatal("read should fail")
+ }
+ err := scanner.Err()
+ if err != io.ErrUnexpectedEOF {
+ t.Errorf("unexpected error: %v", err)
+ }
+}
+
+// Test that Scan finishes if we have endless empty reads.
+type endlessZeros struct{}
+
+func (endlessZeros) Read(p []byte) (int, error) {
+ return 0, nil
+}
+
+func TestBadReader(t *testing.T) {
+ scanner := NewScanner(endlessZeros{})
+ for scanner.Scan() {
+ t.Fatal("read should fail")
+ }
+ err := scanner.Err()
+ if err != io.ErrNoProgress {
+ t.Errorf("unexpected error: %v", err)
+ }
+}
+
+func TestScanWordsExcessiveWhiteSpace(t *testing.T) {
+ const word = "ipsum"
+ s := strings.Repeat(" ", 4*smallMaxTokenSize) + word
+ scanner := NewScanner(strings.NewReader(s))
+ scanner.MaxTokenSize(smallMaxTokenSize)
+ scanner.Split(ScanWords)
+ if !scanner.Scan() {
+ t.Fatalf("scan failed: %v", scanner.Err())
+ }
+ if token := scanner.Text(); token != word {
+ t.Fatalf("unexpected token: %v", token)
+ }
+}
+
+// Test that empty tokens, including at end of line or end of file, are found by the scanner.
+// Issue 8672: Could miss final empty token.
+
+func commaSplit(data []byte, atEOF bool) (advance int, token []byte, err error) {
+ for i := 0; i < len(data); i++ {
+ if data[i] == ',' {
+ return i + 1, data[:i], nil
+ }
+ }
+ return 0, data, ErrFinalToken
+}
+
+func testEmptyTokens(t *testing.T, text string, values []string) {
+ s := NewScanner(strings.NewReader(text))
+ s.Split(commaSplit)
+ var i int
+ for i = 0; s.Scan(); i++ {
+ if i >= len(values) {
+ t.Fatalf("got %d fields, expected %d", i+1, len(values))
+ }
+ if s.Text() != values[i] {
+ t.Errorf("%d: expected %q got %q", i, values[i], s.Text())
+ }
+ }
+ if i != len(values) {
+ t.Fatalf("got %d fields, expected %d", i, len(values))
+ }
+ if err := s.Err(); err != nil {
+ t.Fatal(err)
+ }
+}
+
+func TestEmptyTokens(t *testing.T) {
+ testEmptyTokens(t, "1,2,3,", []string{"1", "2", "3", ""})
+}
+
+func TestWithNoEmptyTokens(t *testing.T) {
+ testEmptyTokens(t, "1,2,3", []string{"1", "2", "3"})
+}
+
+func loopAtEOFSplit(data []byte, atEOF bool) (advance int, token []byte, err error) {
+ if len(data) > 0 {
+ return 1, data[:1], nil
+ }
+ return 0, data, nil
+}
+
+func TestDontLoopForever(t *testing.T) {
+ s := NewScanner(strings.NewReader("abc"))
+ s.Split(loopAtEOFSplit)
+ // Expect a panic
+ defer func() {
+ err := recover()
+ if err == nil {
+ t.Fatal("should have panicked")
+ }
+ if msg, ok := err.(string); !ok || !strings.Contains(msg, "empty tokens") {
+ panic(err)
+ }
+ }()
+ for count := 0; s.Scan(); count++ {
+ if count > 1000 {
+ t.Fatal("looping")
+ }
+ }
+ if s.Err() != nil {
+ t.Fatal("after scan:", s.Err())
+ }
+}
+
+func TestBlankLines(t *testing.T) {
+ s := NewScanner(strings.NewReader(strings.Repeat("\n", 1000)))
+ for count := 0; s.Scan(); count++ {
+ if count > 2000 {
+ t.Fatal("looping")
+ }
+ }
+ if s.Err() != nil {
+ t.Fatal("after scan:", s.Err())
+ }
+}
+
+type countdown int
+
+func (c *countdown) split(data []byte, atEOF bool) (advance int, token []byte, err error) {
+ if *c > 0 {
+ *c--
+ return 1, data[:1], nil
+ }
+ return 0, nil, nil
+}
+
+// Check that the looping-at-EOF check doesn't trigger for merely empty tokens.
+func TestEmptyLinesOK(t *testing.T) {
+ c := countdown(10000)
+ s := NewScanner(strings.NewReader(strings.Repeat("\n", 10000)))
+ s.Split(c.split)
+ for s.Scan() {
+ }
+ if s.Err() != nil {
+ t.Fatal("after scan:", s.Err())
+ }
+ if c != 0 {
+ t.Fatalf("stopped with %d left to process", c)
+ }
+}
+
+// Make sure we can read a huge token if a big enough buffer is provided.
+func TestHugeBuffer(t *testing.T) {
+ text := strings.Repeat("x", 2*MaxScanTokenSize)
+ s := NewScanner(strings.NewReader(text + "\n"))
+ s.Buffer(make([]byte, 100), 3*MaxScanTokenSize)
+ for s.Scan() {
+ token := s.Text()
+ if token != text {
+ t.Errorf("scan got incorrect token of length %d", len(token))
+ }
+ }
+ if s.Err() != nil {
+ t.Fatal("after scan:", s.Err())
+ }
+}
+
+// negativeEOFReader returns an invalid -1 at the end, as though it
+// were wrapping the read system call.
+type negativeEOFReader int
+
+func (r *negativeEOFReader) Read(p []byte) (int, error) {
+ if *r > 0 {
+ c := int(*r)
+ if c > len(p) {
+ c = len(p)
+ }
+ for i := 0; i < c; i++ {
+ p[i] = 'a'
+ }
+ p[c-1] = '\n'
+ *r -= negativeEOFReader(c)
+ return c, nil
+ }
+ return -1, io.EOF
+}
+
+// Test that the scanner doesn't panic and returns ErrBadReadCount
+// on a reader that returns a negative count of bytes read (issue 38053).
+func TestNegativeEOFReader(t *testing.T) {
+ r := negativeEOFReader(10)
+ scanner := NewScanner(&r)
+ c := 0
+ for scanner.Scan() {
+ c++
+ if c > 1 {
+ t.Error("read too many lines")
+ break
+ }
+ }
+ if got, want := scanner.Err(), ErrBadReadCount; got != want {
+ t.Errorf("scanner.Err: got %v, want %v", got, want)
+ }
+}
+
+// largeReader returns an invalid count that is larger than the number
+// of bytes requested.
+type largeReader struct{}
+
+func (largeReader) Read(p []byte) (int, error) {
+ return len(p) + 1, nil
+}
+
+// Test that the scanner doesn't panic and returns ErrBadReadCount
+// on a reader that returns an impossibly large count of bytes read (issue 38053).
+func TestLargeReader(t *testing.T) {
+ scanner := NewScanner(largeReader{})
+ for scanner.Scan() {
+ }
+ if got, want := scanner.Err(), ErrBadReadCount; got != want {
+ t.Errorf("scanner.Err: got %v, want %v", got, want)
+ }
+}
diff --git a/go/src/builtin/builtin.go b/go/src/builtin/builtin.go
new file mode 100644
index 0000000000000000000000000000000000000000..be53077d9cb495e9e1a950ceccf3ceafe76900ce
--- /dev/null
+++ b/go/src/builtin/builtin.go
@@ -0,0 +1,319 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package builtin provides documentation for Go's predeclared identifiers.
+The items documented here are not actually in package builtin
+but their descriptions here allow godoc to present documentation
+for the language's special identifiers.
+*/
+package builtin
+
+import "cmp"
+
+// bool is the set of boolean values, true and false.
+type bool bool
+
+// true and false are the two untyped boolean values.
+const (
+ true = 0 == 0 // Untyped bool.
+ false = 0 != 0 // Untyped bool.
+)
+
+// uint8 is the set of all unsigned 8-bit integers.
+// Range: 0 through 255.
+type uint8 uint8
+
+// uint16 is the set of all unsigned 16-bit integers.
+// Range: 0 through 65535.
+type uint16 uint16
+
+// uint32 is the set of all unsigned 32-bit integers.
+// Range: 0 through 4294967295.
+type uint32 uint32
+
+// uint64 is the set of all unsigned 64-bit integers.
+// Range: 0 through 18446744073709551615.
+type uint64 uint64
+
+// int8 is the set of all signed 8-bit integers.
+// Range: -128 through 127.
+type int8 int8
+
+// int16 is the set of all signed 16-bit integers.
+// Range: -32768 through 32767.
+type int16 int16
+
+// int32 is the set of all signed 32-bit integers.
+// Range: -2147483648 through 2147483647.
+type int32 int32
+
+// int64 is the set of all signed 64-bit integers.
+// Range: -9223372036854775808 through 9223372036854775807.
+type int64 int64
+
+// float32 is the set of all IEEE 754 32-bit floating-point numbers.
+type float32 float32
+
+// float64 is the set of all IEEE 754 64-bit floating-point numbers.
+type float64 float64
+
+// complex64 is the set of all complex numbers with float32 real and
+// imaginary parts.
+type complex64 complex64
+
+// complex128 is the set of all complex numbers with float64 real and
+// imaginary parts.
+type complex128 complex128
+
+// string is the set of all strings of 8-bit bytes, conventionally but not
+// necessarily representing UTF-8-encoded text. A string may be empty, but
+// not nil. Values of string type are immutable.
+type string string
+
+// int is a signed integer type that is at least 32 bits in size. It is a
+// distinct type, however, and not an alias for, say, int32.
+type int int
+
+// uint is an unsigned integer type that is at least 32 bits in size. It is a
+// distinct type, however, and not an alias for, say, uint32.
+type uint uint
+
+// uintptr is an integer type that is large enough to hold the bit pattern of
+// any pointer.
+type uintptr uintptr
+
+// byte is an alias for uint8 and is equivalent to uint8 in all ways. It is
+// used, by convention, to distinguish byte values from 8-bit unsigned
+// integer values.
+type byte = uint8
+
+// rune is an alias for int32 and is equivalent to int32 in all ways. It is
+// used, by convention, to distinguish character values from integer values.
+type rune = int32
+
+// any is an alias for interface{} and is equivalent to interface{} in all ways.
+type any = interface{}
+
+// comparable is an interface that is implemented by all comparable types
+// (booleans, numbers, strings, pointers, channels, arrays of comparable types,
+// structs whose fields are all comparable types).
+// The comparable interface may only be used as a type parameter constraint,
+// not as the type of a variable.
+type comparable interface{ comparable }
+
+// iota is a predeclared identifier representing the untyped integer ordinal
+// number of the current const specification in a (usually parenthesized)
+// const declaration. It is zero-indexed.
+const iota = 0 // Untyped int.
+
+// nil is a predeclared identifier representing the zero value for a
+// pointer, channel, func, interface, map, or slice type.
+var nil Type // Type must be a pointer, channel, func, interface, map, or slice type
+
+// Type is here for the purposes of documentation only. It is a stand-in
+// for any Go type, but represents the same type for any given function
+// invocation.
+type Type int
+
+// Type1 is here for the purposes of documentation only. It is a stand-in
+// for any Go type, but represents the same type for any given function
+// invocation.
+type Type1 int
+
+// TypeOrExpr is here for the purposes of documentation only. It is a stand-in
+// for either a Go type or an expression.
+type TypeOrExpr int
+
+// IntegerType is here for the purposes of documentation only. It is a stand-in
+// for any integer type: int, uint, int8 etc.
+type IntegerType int
+
+// FloatType is here for the purposes of documentation only. It is a stand-in
+// for either float type: float32 or float64.
+type FloatType float32
+
+// ComplexType is here for the purposes of documentation only. It is a
+// stand-in for either complex type: complex64 or complex128.
+type ComplexType complex64
+
+// The append built-in function appends elements to the end of a slice. If
+// it has sufficient capacity, the destination is resliced to accommodate the
+// new elements. If it does not, a new underlying array will be allocated.
+// Append returns the updated slice. It is therefore necessary to store the
+// result of append, often in the variable holding the slice itself:
+//
+// slice = append(slice, elem1, elem2)
+// slice = append(slice, anotherSlice...)
+//
+// As a special case, it is legal to append a string to a byte slice, like this:
+//
+// slice = append([]byte("hello "), "world"...)
+func append(slice []Type, elems ...Type) []Type
+
+// The copy built-in function copies elements from a source slice into a
+// destination slice. (As a special case, it also will copy bytes from a
+// string to a slice of bytes.) The source and destination may overlap. Copy
+// returns the number of elements copied, which will be the minimum of
+// len(src) and len(dst).
+func copy(dst, src []Type) int
+
+// The delete built-in function deletes the element with the specified key
+// (m[key]) from the map. If m is nil or there is no such element, delete
+// is a no-op.
+func delete(m map[Type]Type1, key Type)
+
+// The len built-in function returns the length of v, according to its type:
+//
+// - Array: the number of elements in v.
+// - Pointer to array: the number of elements in *v (even if v is nil).
+// - Slice, or map: the number of elements in v; if v is nil, len(v) is zero.
+// - String: the number of bytes in v.
+// - Channel: the number of elements queued (unread) in the channel buffer;
+// if v is nil, len(v) is zero.
+//
+// For some arguments, such as a string literal or a simple array expression, the
+// result can be a constant. See the Go language specification's "Length and
+// capacity" section for details.
+func len(v Type) int
+
+// The cap built-in function returns the capacity of v, according to its type:
+//
+// - Array: the number of elements in v (same as len(v)).
+// - Pointer to array: the number of elements in *v (same as len(v)).
+// - Slice: the maximum length the slice can reach when resliced;
+// if v is nil, cap(v) is zero.
+// - Channel: the channel buffer capacity, in units of elements;
+// if v is nil, cap(v) is zero.
+//
+// For some arguments, such as a simple array expression, the result can be a
+// constant. See the Go language specification's "Length and capacity" section for
+// details.
+func cap(v Type) int
+
+// The make built-in function allocates and initializes an object of type
+// slice, map, or chan (only). Like new, the first argument is a type, not a
+// value. Unlike new, make's return type is the same as the type of its
+// argument, not a pointer to it. The specification of the result depends on
+// the type:
+//
+// - Slice: The size specifies the length. The capacity of the slice is
+// equal to its length. A second integer argument may be provided to
+// specify a different capacity; it must be no smaller than the
+// length. For example, make([]int, 0, 10) allocates an underlying array
+// of size 10 and returns a slice of length 0 and capacity 10 that is
+// backed by this underlying array.
+// - Map: An empty map is allocated with enough space to hold the
+// specified number of elements. The size may be omitted, in which case
+// a small starting size is allocated.
+// - Channel: The channel's buffer is initialized with the specified
+// buffer capacity. If zero, or the size is omitted, the channel is
+// unbuffered.
+func make(t Type, size ...IntegerType) Type
+
+// The max built-in function returns the largest value of a fixed number of
+// arguments of [cmp.Ordered] types. There must be at least one argument.
+// If T is a floating-point type and any of the arguments are NaNs,
+// max will return NaN.
+func max[T cmp.Ordered](x T, y ...T) T
+
+// The min built-in function returns the smallest value of a fixed number of
+// arguments of [cmp.Ordered] types. There must be at least one argument.
+// If T is a floating-point type and any of the arguments are NaNs,
+// min will return NaN.
+func min[T cmp.Ordered](x T, y ...T) T
+
+// The built-in function new allocates a new, initialized variable and returns
+// a pointer to it. It accepts a single argument, which may be either a type
+// or an expression.
+// If the argument is a type T, then new(T) allocates a variable of type T
+// initialized to its zero value.
+// Otherwise, the argument is an expression x and new(x) allocates a variable
+// of the type of x initialized to the value of x. If that value is an untyped
+// constant, it is first implicitly converted to its default type.
+func new(TypeOrExpr) *Type
+
+// The complex built-in function constructs a complex value from two
+// floating-point values. The real and imaginary parts must be of the same
+// size, either float32 or float64 (or assignable to them), and the return
+// value will be the corresponding complex type (complex64 for float32,
+// complex128 for float64).
+func complex(r, i FloatType) ComplexType
+
+// The real built-in function returns the real part of the complex number c.
+// The return value will be floating point type corresponding to the type of c.
+func real(c ComplexType) FloatType
+
+// The imag built-in function returns the imaginary part of the complex
+// number c. The return value will be floating point type corresponding to
+// the type of c.
+func imag(c ComplexType) FloatType
+
+// The clear built-in function clears maps and slices.
+// For maps, clear deletes all entries, resulting in an empty map.
+// For slices, clear sets all elements up to the length of the slice
+// to the zero value of the respective element type. If the argument
+// type is a type parameter, the type parameter's type set must
+// contain only map or slice types, and clear performs the operation
+// implied by the type argument. If t is nil, clear is a no-op.
+func clear[T ~[]Type | ~map[Type]Type1](t T)
+
+// The close built-in function closes a channel, which must be either
+// bidirectional or send-only. It should be executed only by the sender,
+// never the receiver, and has the effect of shutting down the channel after
+// the last sent value is received. After the last value has been received
+// from a closed channel c, any receive from c will succeed without
+// blocking, returning the zero value for the channel element. The form
+//
+// x, ok := <-c
+//
+// will also set ok to false for a closed and empty channel.
+func close(c chan<- Type)
+
+// The panic built-in function stops normal execution of the current
+// goroutine. When a function F calls panic, normal execution of F stops
+// immediately. Any functions whose execution was deferred by F are run in
+// the usual way, and then F returns to its caller. To the caller G, the
+// invocation of F then behaves like a call to panic, terminating G's
+// execution and running any deferred functions. This continues until all
+// functions in the executing goroutine have stopped, in reverse order. At
+// that point, the program is terminated with a non-zero exit code. This
+// termination sequence is called panicking and can be controlled by the
+// built-in function recover.
+//
+// Starting in Go 1.21, calling panic with a nil interface value or an
+// untyped nil causes a run-time error (a different panic).
+// The GODEBUG setting panicnil=1 disables the run-time error.
+func panic(v any)
+
+// The recover built-in function allows a program to manage behavior of a
+// panicking goroutine. Executing a call to recover inside a deferred
+// function (but not any function called by it) stops the panicking sequence
+// by restoring normal execution and retrieves the error value passed to the
+// call of panic. If recover is called outside the deferred function it will
+// not stop a panicking sequence. In this case, or when the goroutine is not
+// panicking, recover returns nil.
+//
+// Prior to Go 1.21, recover would also return nil if panic is called with
+// a nil argument. See [panic] for details.
+func recover() any
+
+// The print built-in function formats its arguments in an
+// implementation-specific way and writes the result to standard error.
+// Print is useful for bootstrapping and debugging; it is not guaranteed
+// to stay in the language.
+func print(args ...Type)
+
+// The println built-in function formats its arguments in an
+// implementation-specific way and writes the result to standard error.
+// Spaces are always added between arguments and a newline is appended.
+// Println is useful for bootstrapping and debugging; it is not guaranteed
+// to stay in the language.
+func println(args ...Type)
+
+// The error built-in interface type is the conventional interface for
+// representing an error condition, with the nil value representing no error.
+type error interface {
+ Error() string
+}
diff --git a/go/src/bytes/boundary_test.go b/go/src/bytes/boundary_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..67f377e089634f15f06069c28d4779bb161b1614
--- /dev/null
+++ b/go/src/bytes/boundary_test.go
@@ -0,0 +1,115 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+//
+//go:build linux
+
+package bytes_test
+
+import (
+ . "bytes"
+ "syscall"
+ "testing"
+)
+
+// This file tests the situation where byte operations are checking
+// data very near to a page boundary. We want to make sure those
+// operations do not read across the boundary and cause a page
+// fault where they shouldn't.
+
+// These tests run only on linux. The code being tested is
+// not OS-specific, so it does not need to be tested on all
+// operating systems.
+
+// dangerousSlice returns a slice which is immediately
+// preceded and followed by a faulting page.
+func dangerousSlice(t *testing.T) []byte {
+ pagesize := syscall.Getpagesize()
+ b, err := syscall.Mmap(0, 0, 3*pagesize, syscall.PROT_READ|syscall.PROT_WRITE, syscall.MAP_ANONYMOUS|syscall.MAP_PRIVATE)
+ if err != nil {
+ t.Fatalf("mmap failed %s", err)
+ }
+ err = syscall.Mprotect(b[:pagesize], syscall.PROT_NONE)
+ if err != nil {
+ t.Fatalf("mprotect low failed %s\n", err)
+ }
+ err = syscall.Mprotect(b[2*pagesize:], syscall.PROT_NONE)
+ if err != nil {
+ t.Fatalf("mprotect high failed %s\n", err)
+ }
+ return b[pagesize : 2*pagesize]
+}
+
+func TestEqualNearPageBoundary(t *testing.T) {
+ t.Parallel()
+ b := dangerousSlice(t)
+ for i := range b {
+ b[i] = 'A'
+ }
+ for i := 0; i <= len(b); i++ {
+ Equal(b[:i], b[len(b)-i:])
+ Equal(b[len(b)-i:], b[:i])
+ }
+}
+
+func TestIndexByteNearPageBoundary(t *testing.T) {
+ t.Parallel()
+ b := dangerousSlice(t)
+ for i := range b {
+ idx := IndexByte(b[i:], 1)
+ if idx != -1 {
+ t.Fatalf("IndexByte(b[%d:])=%d, want -1\n", i, idx)
+ }
+ }
+}
+
+func TestIndexNearPageBoundary(t *testing.T) {
+ t.Parallel()
+ q := dangerousSlice(t)
+ if len(q) > 64 {
+ // Only worry about when we're near the end of a page.
+ q = q[len(q)-64:]
+ }
+ b := dangerousSlice(t)
+ if len(b) > 256 {
+ // Only worry about when we're near the end of a page.
+ b = b[len(b)-256:]
+ }
+ for j := 1; j < len(q); j++ {
+ q[j-1] = 1 // difference is only found on the last byte
+ for i := range b {
+ idx := Index(b[i:], q[:j])
+ if idx != -1 {
+ t.Fatalf("Index(b[%d:], q[:%d])=%d, want -1\n", i, j, idx)
+ }
+ }
+ q[j-1] = 0
+ }
+
+ // Test differing alignments and sizes of q which always end on a page boundary.
+ q[len(q)-1] = 1 // difference is only found on the last byte
+ for j := 0; j < len(q); j++ {
+ for i := range b {
+ idx := Index(b[i:], q[j:])
+ if idx != -1 {
+ t.Fatalf("Index(b[%d:], q[%d:])=%d, want -1\n", i, j, idx)
+ }
+ }
+ }
+ q[len(q)-1] = 0
+}
+
+func TestCountNearPageBoundary(t *testing.T) {
+ t.Parallel()
+ b := dangerousSlice(t)
+ for i := range b {
+ c := Count(b[i:], []byte{1})
+ if c != 0 {
+ t.Fatalf("Count(b[%d:], {1})=%d, want 0\n", i, c)
+ }
+ c = Count(b[:i], []byte{0})
+ if c != i {
+ t.Fatalf("Count(b[:%d], {0})=%d, want %d\n", i, c, i)
+ }
+ }
+}
diff --git a/go/src/bytes/buffer.go b/go/src/bytes/buffer.go
new file mode 100644
index 0000000000000000000000000000000000000000..6cb4d6a8f66ebf556eb4543f495ec8d537889fd9
--- /dev/null
+++ b/go/src/bytes/buffer.go
@@ -0,0 +1,500 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bytes
+
+// Simple byte buffer for marshaling data.
+
+import (
+ "errors"
+ "io"
+ "unicode/utf8"
+)
+
+// smallBufferSize is an initial allocation minimal capacity.
+const smallBufferSize = 64
+
+// A Buffer is a variable-sized buffer of bytes with [Buffer.Read] and [Buffer.Write] methods.
+// The zero value for Buffer is an empty buffer ready to use.
+type Buffer struct {
+ buf []byte // contents are the bytes buf[off : len(buf)]
+ off int // read at &buf[off], write at &buf[len(buf)]
+ lastRead readOp // last read operation, so that Unread* can work correctly.
+
+ // Copying and modifying a non-zero Buffer is prone to error,
+ // but we cannot employ the noCopy trick used by WaitGroup and Mutex,
+ // which causes vet's copylocks checker to report misuse, as vet
+ // cannot reliably distinguish the zero and non-zero cases.
+ // See #26462, #25907, #47276, #48398 for history.
+}
+
+// The readOp constants describe the last action performed on
+// the buffer, so that UnreadRune and UnreadByte can check for
+// invalid usage. opReadRuneX constants are chosen such that
+// converted to int they correspond to the rune size that was read.
+type readOp int8
+
+// Don't use iota for these, as the values need to correspond with the
+// names and comments, which is easier to see when being explicit.
+const (
+ opRead readOp = -1 // Any other read operation.
+ opInvalid readOp = 0 // Non-read operation.
+ opReadRune1 readOp = 1 // Read rune of size 1.
+ opReadRune2 readOp = 2 // Read rune of size 2.
+ opReadRune3 readOp = 3 // Read rune of size 3.
+ opReadRune4 readOp = 4 // Read rune of size 4.
+)
+
+// ErrTooLarge is passed to panic if memory cannot be allocated to store data in a buffer.
+var ErrTooLarge = errors.New("bytes.Buffer: too large")
+var errNegativeRead = errors.New("bytes.Buffer: reader returned negative count from Read")
+
+const maxInt = int(^uint(0) >> 1)
+
+// Bytes returns a slice of length b.Len() holding the unread portion of the buffer.
+// The slice is valid for use only until the next buffer modification (that is,
+// only until the next call to a method like [Buffer.Read], [Buffer.Write], [Buffer.Reset], or [Buffer.Truncate]).
+// The slice aliases the buffer content at least until the next buffer modification,
+// so immediate changes to the slice will affect the result of future reads.
+func (b *Buffer) Bytes() []byte { return b.buf[b.off:] }
+
+// AvailableBuffer returns an empty buffer with b.Available() capacity.
+// This buffer is intended to be appended to and
+// passed to an immediately succeeding [Buffer.Write] call.
+// The buffer is only valid until the next write operation on b.
+func (b *Buffer) AvailableBuffer() []byte { return b.buf[len(b.buf):] }
+
+// String returns the contents of the unread portion of the buffer
+// as a string. If the [Buffer] is a nil pointer, it returns "".
+//
+// To build strings more efficiently, see the [strings.Builder] type.
+func (b *Buffer) String() string {
+ if b == nil {
+ // Special case, useful in debugging.
+ return ""
+ }
+ return string(b.buf[b.off:])
+}
+
+// Peek returns the next n bytes without advancing the buffer.
+// If Peek returns fewer than n bytes, it also returns [io.EOF].
+// The slice is only valid until the next call to a read or write method.
+// The slice aliases the buffer content at least until the next buffer modification,
+// so immediate changes to the slice will affect the result of future reads.
+func (b *Buffer) Peek(n int) ([]byte, error) {
+ if b.Len() < n {
+ return b.buf[b.off:], io.EOF
+ }
+ return b.buf[b.off : b.off+n], nil
+}
+
+// empty reports whether the unread portion of the buffer is empty.
+func (b *Buffer) empty() bool { return len(b.buf) <= b.off }
+
+// Len returns the number of bytes of the unread portion of the buffer;
+// b.Len() == len(b.Bytes()).
+func (b *Buffer) Len() int { return len(b.buf) - b.off }
+
+// Cap returns the capacity of the buffer's underlying byte slice, that is, the
+// total space allocated for the buffer's data.
+func (b *Buffer) Cap() int { return cap(b.buf) }
+
+// Available returns how many bytes are unused in the buffer.
+func (b *Buffer) Available() int { return cap(b.buf) - len(b.buf) }
+
+// Truncate discards all but the first n unread bytes from the buffer
+// but continues to use the same allocated storage.
+// It panics if n is negative or greater than the length of the buffer.
+func (b *Buffer) Truncate(n int) {
+ if n == 0 {
+ b.Reset()
+ return
+ }
+ b.lastRead = opInvalid
+ if n < 0 || n > b.Len() {
+ panic("bytes.Buffer: truncation out of range")
+ }
+ b.buf = b.buf[:b.off+n]
+}
+
+// Reset resets the buffer to be empty,
+// but it retains the underlying storage for use by future writes.
+// Reset is the same as [Buffer.Truncate](0).
+func (b *Buffer) Reset() {
+ b.buf = b.buf[:0]
+ b.off = 0
+ b.lastRead = opInvalid
+}
+
+// tryGrowByReslice is an inlineable version of grow for the fast-case where the
+// internal buffer only needs to be resliced.
+// It returns the index where bytes should be written and whether it succeeded.
+func (b *Buffer) tryGrowByReslice(n int) (int, bool) {
+ if l := len(b.buf); n <= cap(b.buf)-l {
+ b.buf = b.buf[:l+n]
+ return l, true
+ }
+ return 0, false
+}
+
+// grow grows the buffer to guarantee space for n more bytes.
+// It returns the index where bytes should be written.
+// If the buffer can't grow it will panic with ErrTooLarge.
+func (b *Buffer) grow(n int) int {
+ m := b.Len()
+ // If buffer is empty, reset to recover space.
+ if m == 0 && b.off != 0 {
+ b.Reset()
+ }
+ // Try to grow by means of a reslice.
+ if i, ok := b.tryGrowByReslice(n); ok {
+ return i
+ }
+ if b.buf == nil && n <= smallBufferSize {
+ b.buf = make([]byte, n, smallBufferSize)
+ return 0
+ }
+ c := cap(b.buf)
+ if n <= c/2-m {
+ // We can slide things down instead of allocating a new
+ // slice. We only need m+n <= c to slide, but
+ // we instead let capacity get twice as large so we
+ // don't spend all our time copying.
+ copy(b.buf, b.buf[b.off:])
+ } else if c > maxInt-c-n {
+ panic(ErrTooLarge)
+ } else {
+ // Add b.off to account for b.buf[:b.off] being sliced off the front.
+ b.buf = growSlice(b.buf[b.off:], b.off+n)
+ }
+ // Restore b.off and len(b.buf).
+ b.off = 0
+ b.buf = b.buf[:m+n]
+ return m
+}
+
+// Grow grows the buffer's capacity, if necessary, to guarantee space for
+// another n bytes. After Grow(n), at least n bytes can be written to the
+// buffer without another allocation.
+// If n is negative, Grow will panic.
+// If the buffer can't grow it will panic with [ErrTooLarge].
+func (b *Buffer) Grow(n int) {
+ if n < 0 {
+ panic("bytes.Buffer.Grow: negative count")
+ }
+ m := b.grow(n)
+ b.buf = b.buf[:m]
+}
+
+// Write appends the contents of p to the buffer, growing the buffer as
+// needed. The return value n is the length of p; err is always nil. If the
+// buffer becomes too large, Write will panic with [ErrTooLarge].
+func (b *Buffer) Write(p []byte) (n int, err error) {
+ b.lastRead = opInvalid
+ m, ok := b.tryGrowByReslice(len(p))
+ if !ok {
+ m = b.grow(len(p))
+ }
+ return copy(b.buf[m:], p), nil
+}
+
+// WriteString appends the contents of s to the buffer, growing the buffer as
+// needed. The return value n is the length of s; err is always nil. If the
+// buffer becomes too large, WriteString will panic with [ErrTooLarge].
+func (b *Buffer) WriteString(s string) (n int, err error) {
+ b.lastRead = opInvalid
+ m, ok := b.tryGrowByReslice(len(s))
+ if !ok {
+ m = b.grow(len(s))
+ }
+ return copy(b.buf[m:], s), nil
+}
+
+// MinRead is the minimum slice size passed to a [Buffer.Read] call by
+// [Buffer.ReadFrom]. As long as the [Buffer] has at least MinRead bytes beyond
+// what is required to hold the contents of r, [Buffer.ReadFrom] will not grow the
+// underlying buffer.
+const MinRead = 512
+
+// ReadFrom reads data from r until EOF and appends it to the buffer, growing
+// the buffer as needed. The return value n is the number of bytes read. Any
+// error except io.EOF encountered during the read is also returned. If the
+// buffer becomes too large, ReadFrom will panic with [ErrTooLarge].
+func (b *Buffer) ReadFrom(r io.Reader) (n int64, err error) {
+ b.lastRead = opInvalid
+ for {
+ i := b.grow(MinRead)
+ b.buf = b.buf[:i]
+ m, e := r.Read(b.buf[i:cap(b.buf)])
+ if m < 0 {
+ panic(errNegativeRead)
+ }
+
+ b.buf = b.buf[:i+m]
+ n += int64(m)
+ if e == io.EOF {
+ return n, nil // e is EOF, so return nil explicitly
+ }
+ if e != nil {
+ return n, e
+ }
+ }
+}
+
+// growSlice grows b by n, preserving the original content of b.
+// If the allocation fails, it panics with ErrTooLarge.
+func growSlice(b []byte, n int) []byte {
+ defer func() {
+ if recover() != nil {
+ panic(ErrTooLarge)
+ }
+ }()
+ // TODO(http://golang.org/issue/51462): We should rely on the append-make
+ // pattern so that the compiler can call runtime.growslice. For example:
+ // return append(b, make([]byte, n)...)
+ // This avoids unnecessary zero-ing of the first len(b) bytes of the
+ // allocated slice, but this pattern causes b to escape onto the heap.
+ //
+ // Instead use the append-make pattern with a nil slice to ensure that
+ // we allocate buffers rounded up to the closest size class.
+ c := len(b) + n // ensure enough space for n elements
+ if c < 2*cap(b) {
+ // The growth rate has historically always been 2x. In the future,
+ // we could rely purely on append to determine the growth rate.
+ c = 2 * cap(b)
+ }
+ b2 := append([]byte(nil), make([]byte, c)...)
+ i := copy(b2, b)
+ return b2[:i]
+}
+
+// WriteTo writes data to w until the buffer is drained or an error occurs.
+// The return value n is the number of bytes written; it always fits into an
+// int, but it is int64 to match the [io.WriterTo] interface. Any error
+// encountered during the write is also returned.
+func (b *Buffer) WriteTo(w io.Writer) (n int64, err error) {
+ b.lastRead = opInvalid
+ if nBytes := b.Len(); nBytes > 0 {
+ m, e := w.Write(b.buf[b.off:])
+ if m > nBytes {
+ panic("bytes.Buffer.WriteTo: invalid Write count")
+ }
+ b.off += m
+ n = int64(m)
+ if e != nil {
+ return n, e
+ }
+ // all bytes should have been written, by definition of
+ // Write method in io.Writer
+ if m != nBytes {
+ return n, io.ErrShortWrite
+ }
+ }
+ // Buffer is now empty; reset.
+ b.Reset()
+ return n, nil
+}
+
+// WriteByte appends the byte c to the buffer, growing the buffer as needed.
+// The returned error is always nil, but is included to match [bufio.Writer]'s
+// WriteByte. If the buffer becomes too large, WriteByte will panic with
+// [ErrTooLarge].
+func (b *Buffer) WriteByte(c byte) error {
+ b.lastRead = opInvalid
+ m, ok := b.tryGrowByReslice(1)
+ if !ok {
+ m = b.grow(1)
+ }
+ b.buf[m] = c
+ return nil
+}
+
+// WriteRune appends the UTF-8 encoding of Unicode code point r to the
+// buffer, returning its length and an error, which is always nil but is
+// included to match [bufio.Writer]'s WriteRune. The buffer is grown as needed;
+// if it becomes too large, WriteRune will panic with [ErrTooLarge].
+func (b *Buffer) WriteRune(r rune) (n int, err error) {
+ // Compare as uint32 to correctly handle negative runes.
+ if uint32(r) < utf8.RuneSelf {
+ b.WriteByte(byte(r))
+ return 1, nil
+ }
+ b.lastRead = opInvalid
+ m, ok := b.tryGrowByReslice(utf8.UTFMax)
+ if !ok {
+ m = b.grow(utf8.UTFMax)
+ }
+ b.buf = utf8.AppendRune(b.buf[:m], r)
+ return len(b.buf) - m, nil
+}
+
+// Read reads the next len(p) bytes from the buffer or until the buffer
+// is drained. The return value n is the number of bytes read. If the
+// buffer has no data to return, err is [io.EOF] (unless len(p) is zero);
+// otherwise it is nil.
+func (b *Buffer) Read(p []byte) (n int, err error) {
+ b.lastRead = opInvalid
+ if b.empty() {
+ // Buffer is empty, reset to recover space.
+ b.Reset()
+ if len(p) == 0 {
+ return 0, nil
+ }
+ return 0, io.EOF
+ }
+ n = copy(p, b.buf[b.off:])
+ b.off += n
+ if n > 0 {
+ b.lastRead = opRead
+ }
+ return n, nil
+}
+
+// Next returns a slice containing the next n bytes from the buffer,
+// advancing the buffer as if the bytes had been returned by [Buffer.Read].
+// If there are fewer than n bytes in the buffer, Next returns the entire buffer.
+// The slice is only valid until the next call to a read or write method.
+func (b *Buffer) Next(n int) []byte {
+ b.lastRead = opInvalid
+ m := b.Len()
+ if n > m {
+ n = m
+ }
+ data := b.buf[b.off : b.off+n]
+ b.off += n
+ if n > 0 {
+ b.lastRead = opRead
+ }
+ return data
+}
+
+// ReadByte reads and returns the next byte from the buffer.
+// If no byte is available, it returns error [io.EOF].
+func (b *Buffer) ReadByte() (byte, error) {
+ if b.empty() {
+ // Buffer is empty, reset to recover space.
+ b.Reset()
+ return 0, io.EOF
+ }
+ c := b.buf[b.off]
+ b.off++
+ b.lastRead = opRead
+ return c, nil
+}
+
+// ReadRune reads and returns the next UTF-8-encoded
+// Unicode code point from the buffer.
+// If no bytes are available, the error returned is io.EOF.
+// If the bytes are an erroneous UTF-8 encoding, it
+// consumes one byte and returns U+FFFD, 1.
+func (b *Buffer) ReadRune() (r rune, size int, err error) {
+ if b.empty() {
+ // Buffer is empty, reset to recover space.
+ b.Reset()
+ return 0, 0, io.EOF
+ }
+ c := b.buf[b.off]
+ if c < utf8.RuneSelf {
+ b.off++
+ b.lastRead = opReadRune1
+ return rune(c), 1, nil
+ }
+ r, n := utf8.DecodeRune(b.buf[b.off:])
+ b.off += n
+ b.lastRead = readOp(n)
+ return r, n, nil
+}
+
+// UnreadRune unreads the last rune returned by [Buffer.ReadRune].
+// If the most recent read or write operation on the buffer was
+// not a successful [Buffer.ReadRune], UnreadRune returns an error. (In this regard
+// it is stricter than [Buffer.UnreadByte], which will unread the last byte
+// from any read operation.)
+func (b *Buffer) UnreadRune() error {
+ if b.lastRead <= opInvalid {
+ return errors.New("bytes.Buffer: UnreadRune: previous operation was not a successful ReadRune")
+ }
+ if b.off >= int(b.lastRead) {
+ b.off -= int(b.lastRead)
+ }
+ b.lastRead = opInvalid
+ return nil
+}
+
+var errUnreadByte = errors.New("bytes.Buffer: UnreadByte: previous operation was not a successful read")
+
+// UnreadByte unreads the last byte returned by the most recent successful
+// read operation that read at least one byte. If a write has happened since
+// the last read, if the last read returned an error, or if the read read zero
+// bytes, UnreadByte returns an error.
+func (b *Buffer) UnreadByte() error {
+ if b.lastRead == opInvalid {
+ return errUnreadByte
+ }
+ b.lastRead = opInvalid
+ if b.off > 0 {
+ b.off--
+ }
+ return nil
+}
+
+// ReadBytes reads until the first occurrence of delim in the input,
+// returning a slice containing the data up to and including the delimiter.
+// If ReadBytes encounters an error before finding a delimiter,
+// it returns the data read before the error and the error itself (often [io.EOF]).
+// ReadBytes returns err != nil if and only if the returned data does not end in
+// delim.
+func (b *Buffer) ReadBytes(delim byte) (line []byte, err error) {
+ slice, err := b.readSlice(delim)
+ // return a copy of slice. The buffer's backing array may
+ // be overwritten by later calls.
+ line = append(line, slice...)
+ return line, err
+}
+
+// readSlice is like ReadBytes but returns a reference to internal buffer data.
+func (b *Buffer) readSlice(delim byte) (line []byte, err error) {
+ i := IndexByte(b.buf[b.off:], delim)
+ end := b.off + i + 1
+ if i < 0 {
+ end = len(b.buf)
+ err = io.EOF
+ }
+ line = b.buf[b.off:end]
+ b.off = end
+ b.lastRead = opRead
+ return line, err
+}
+
+// ReadString reads until the first occurrence of delim in the input,
+// returning a string containing the data up to and including the delimiter.
+// If ReadString encounters an error before finding a delimiter,
+// it returns the data read before the error and the error itself (often [io.EOF]).
+// ReadString returns err != nil if and only if the returned data does not end
+// in delim.
+func (b *Buffer) ReadString(delim byte) (line string, err error) {
+ slice, err := b.readSlice(delim)
+ return string(slice), err
+}
+
+// NewBuffer creates and initializes a new [Buffer] using buf as its
+// initial contents. The new [Buffer] takes ownership of buf, and the
+// caller should not use buf after this call. NewBuffer is intended to
+// prepare a [Buffer] to read existing data. It can also be used to set
+// the initial size of the internal buffer for writing. To do that,
+// buf should have the desired capacity but a length of zero.
+//
+// In most cases, new([Buffer]) (or just declaring a [Buffer] variable) is
+// sufficient to initialize a [Buffer].
+func NewBuffer(buf []byte) *Buffer { return &Buffer{buf: buf} }
+
+// NewBufferString creates and initializes a new [Buffer] using string s as its
+// initial contents. It is intended to prepare a buffer to read an existing
+// string.
+//
+// In most cases, new([Buffer]) (or just declaring a [Buffer] variable) is
+// sufficient to initialize a [Buffer].
+func NewBufferString(s string) *Buffer {
+ return &Buffer{buf: []byte(s)}
+}
diff --git a/go/src/bytes/buffer_test.go b/go/src/bytes/buffer_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..9c1ba0a838054f38d7d68890312843af7daf594d
--- /dev/null
+++ b/go/src/bytes/buffer_test.go
@@ -0,0 +1,781 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bytes_test
+
+import (
+ . "bytes"
+ "fmt"
+ "internal/testenv"
+ "io"
+ "math/rand"
+ "strconv"
+ "testing"
+ "unicode/utf8"
+)
+
+const N = 10000 // make this bigger for a larger (and slower) test
+var testString string // test data for write tests
+var testBytes []byte // test data; same as testString but as a slice.
+
+type negativeReader struct{}
+
+func (r *negativeReader) Read([]byte) (int, error) { return -1, nil }
+
+func init() {
+ testBytes = make([]byte, N)
+ for i := 0; i < N; i++ {
+ testBytes[i] = 'a' + byte(i%26)
+ }
+ testString = string(testBytes)
+}
+
+// Verify that contents of buf match the string s.
+func check(t *testing.T, testname string, buf *Buffer, s string) {
+ bytes := buf.Bytes()
+ str := buf.String()
+ if buf.Len() != len(bytes) {
+ t.Errorf("%s: buf.Len() == %d, len(buf.Bytes()) == %d", testname, buf.Len(), len(bytes))
+ }
+
+ if buf.Len() != len(str) {
+ t.Errorf("%s: buf.Len() == %d, len(buf.String()) == %d", testname, buf.Len(), len(str))
+ }
+
+ if buf.Len() != len(s) {
+ t.Errorf("%s: buf.Len() == %d, len(s) == %d", testname, buf.Len(), len(s))
+ }
+
+ if string(bytes) != s {
+ t.Errorf("%s: string(buf.Bytes()) == %q, s == %q", testname, string(bytes), s)
+ }
+}
+
+// Fill buf through n writes of string fus.
+// The initial contents of buf corresponds to the string s;
+// the result is the final contents of buf returned as a string.
+func fillString(t *testing.T, testname string, buf *Buffer, s string, n int, fus string) string {
+ check(t, testname+" (fill 1)", buf, s)
+ for ; n > 0; n-- {
+ m, err := buf.WriteString(fus)
+ if m != len(fus) {
+ t.Errorf(testname+" (fill 2): m == %d, expected %d", m, len(fus))
+ }
+ if err != nil {
+ t.Errorf(testname+" (fill 3): err should always be nil, found err == %s", err)
+ }
+ s += fus
+ check(t, testname+" (fill 4)", buf, s)
+ }
+ return s
+}
+
+// Fill buf through n writes of byte slice fub.
+// The initial contents of buf corresponds to the string s;
+// the result is the final contents of buf returned as a string.
+func fillBytes(t *testing.T, testname string, buf *Buffer, s string, n int, fub []byte) string {
+ check(t, testname+" (fill 1)", buf, s)
+ for ; n > 0; n-- {
+ m, err := buf.Write(fub)
+ if m != len(fub) {
+ t.Errorf(testname+" (fill 2): m == %d, expected %d", m, len(fub))
+ }
+ if err != nil {
+ t.Errorf(testname+" (fill 3): err should always be nil, found err == %s", err)
+ }
+ s += string(fub)
+ check(t, testname+" (fill 4)", buf, s)
+ }
+ return s
+}
+
+func TestNewBuffer(t *testing.T) {
+ buf := NewBuffer(testBytes)
+ check(t, "NewBuffer", buf, testString)
+}
+
+var buf Buffer
+
+// Calling NewBuffer and immediately shallow copying the Buffer struct
+// should not result in any allocations.
+// This can be used to reset the underlying []byte of an existing Buffer.
+func TestNewBufferShallow(t *testing.T) {
+ testenv.SkipIfOptimizationOff(t)
+ n := testing.AllocsPerRun(1000, func() {
+ buf = *NewBuffer(testBytes)
+ })
+ if n > 0 {
+ t.Errorf("allocations occurred while shallow copying")
+ }
+ check(t, "NewBuffer", &buf, testString)
+}
+
+func TestNewBufferString(t *testing.T) {
+ buf := NewBufferString(testString)
+ check(t, "NewBufferString", buf, testString)
+}
+
+// Empty buf through repeated reads into fub.
+// The initial contents of buf corresponds to the string s.
+func empty(t *testing.T, testname string, buf *Buffer, s string, fub []byte) {
+ check(t, testname+" (empty 1)", buf, s)
+
+ for {
+ n, err := buf.Read(fub)
+ if n == 0 {
+ break
+ }
+ if err != nil {
+ t.Errorf(testname+" (empty 2): err should always be nil, found err == %s", err)
+ }
+ s = s[n:]
+ check(t, testname+" (empty 3)", buf, s)
+ }
+
+ check(t, testname+" (empty 4)", buf, "")
+}
+
+func TestBasicOperations(t *testing.T) {
+ var buf Buffer
+
+ for i := 0; i < 5; i++ {
+ check(t, "TestBasicOperations (1)", &buf, "")
+
+ buf.Reset()
+ check(t, "TestBasicOperations (2)", &buf, "")
+
+ buf.Truncate(0)
+ check(t, "TestBasicOperations (3)", &buf, "")
+
+ n, err := buf.Write(testBytes[0:1])
+ if want := 1; err != nil || n != want {
+ t.Errorf("Write: got (%d, %v), want (%d, %v)", n, err, want, nil)
+ }
+ check(t, "TestBasicOperations (4)", &buf, "a")
+
+ buf.WriteByte(testString[1])
+ check(t, "TestBasicOperations (5)", &buf, "ab")
+
+ n, err = buf.Write(testBytes[2:26])
+ if want := 24; err != nil || n != want {
+ t.Errorf("Write: got (%d, %v), want (%d, %v)", n, err, want, nil)
+ }
+ check(t, "TestBasicOperations (6)", &buf, testString[0:26])
+
+ buf.Truncate(26)
+ check(t, "TestBasicOperations (7)", &buf, testString[0:26])
+
+ buf.Truncate(20)
+ check(t, "TestBasicOperations (8)", &buf, testString[0:20])
+
+ empty(t, "TestBasicOperations (9)", &buf, testString[0:20], make([]byte, 5))
+ empty(t, "TestBasicOperations (10)", &buf, "", make([]byte, 100))
+
+ buf.WriteByte(testString[1])
+ c, err := buf.ReadByte()
+ if want := testString[1]; err != nil || c != want {
+ t.Errorf("ReadByte: got (%q, %v), want (%q, %v)", c, err, want, nil)
+ }
+ c, err = buf.ReadByte()
+ if err != io.EOF {
+ t.Errorf("ReadByte: got (%q, %v), want (%q, %v)", c, err, byte(0), io.EOF)
+ }
+ }
+}
+
+func TestLargeStringWrites(t *testing.T) {
+ var buf Buffer
+ limit := 30
+ if testing.Short() {
+ limit = 9
+ }
+ for i := 3; i < limit; i += 3 {
+ s := fillString(t, "TestLargeWrites (1)", &buf, "", 5, testString)
+ empty(t, "TestLargeStringWrites (2)", &buf, s, make([]byte, len(testString)/i))
+ }
+ check(t, "TestLargeStringWrites (3)", &buf, "")
+}
+
+func TestLargeByteWrites(t *testing.T) {
+ var buf Buffer
+ limit := 30
+ if testing.Short() {
+ limit = 9
+ }
+ for i := 3; i < limit; i += 3 {
+ s := fillBytes(t, "TestLargeWrites (1)", &buf, "", 5, testBytes)
+ empty(t, "TestLargeByteWrites (2)", &buf, s, make([]byte, len(testString)/i))
+ }
+ check(t, "TestLargeByteWrites (3)", &buf, "")
+}
+
+func TestLargeStringReads(t *testing.T) {
+ var buf Buffer
+ for i := 3; i < 30; i += 3 {
+ s := fillString(t, "TestLargeReads (1)", &buf, "", 5, testString[:len(testString)/i])
+ empty(t, "TestLargeReads (2)", &buf, s, make([]byte, len(testString)))
+ }
+ check(t, "TestLargeStringReads (3)", &buf, "")
+}
+
+func TestLargeByteReads(t *testing.T) {
+ var buf Buffer
+ for i := 3; i < 30; i += 3 {
+ s := fillBytes(t, "TestLargeReads (1)", &buf, "", 5, testBytes[:len(testBytes)/i])
+ empty(t, "TestLargeReads (2)", &buf, s, make([]byte, len(testString)))
+ }
+ check(t, "TestLargeByteReads (3)", &buf, "")
+}
+
+func TestMixedReadsAndWrites(t *testing.T) {
+ var buf Buffer
+ s := ""
+ for i := 0; i < 50; i++ {
+ wlen := rand.Intn(len(testString))
+ if i%2 == 0 {
+ s = fillString(t, "TestMixedReadsAndWrites (1)", &buf, s, 1, testString[0:wlen])
+ } else {
+ s = fillBytes(t, "TestMixedReadsAndWrites (1)", &buf, s, 1, testBytes[0:wlen])
+ }
+
+ rlen := rand.Intn(len(testString))
+ fub := make([]byte, rlen)
+ n, _ := buf.Read(fub)
+ s = s[n:]
+ }
+ empty(t, "TestMixedReadsAndWrites (2)", &buf, s, make([]byte, buf.Len()))
+}
+
+func TestCapWithPreallocatedSlice(t *testing.T) {
+ buf := NewBuffer(make([]byte, 10))
+ n := buf.Cap()
+ if n != 10 {
+ t.Errorf("expected 10, got %d", n)
+ }
+}
+
+func TestCapWithSliceAndWrittenData(t *testing.T) {
+ buf := NewBuffer(make([]byte, 0, 10))
+ buf.Write([]byte("test"))
+ n := buf.Cap()
+ if n != 10 {
+ t.Errorf("expected 10, got %d", n)
+ }
+}
+
+func TestNil(t *testing.T) {
+ var b *Buffer
+ if b.String() != "" {
+ t.Errorf("expected ; got %q", b.String())
+ }
+}
+
+func TestReadFrom(t *testing.T) {
+ var buf Buffer
+ for i := 3; i < 30; i += 3 {
+ s := fillBytes(t, "TestReadFrom (1)", &buf, "", 5, testBytes[:len(testBytes)/i])
+ var b Buffer
+ b.ReadFrom(&buf)
+ empty(t, "TestReadFrom (2)", &b, s, make([]byte, len(testString)))
+ }
+}
+
+type panicReader struct{ panic bool }
+
+func (r panicReader) Read(p []byte) (int, error) {
+ if r.panic {
+ panic("oops")
+ }
+ return 0, io.EOF
+}
+
+// Make sure that an empty Buffer remains empty when
+// it is "grown" before a Read that panics
+func TestReadFromPanicReader(t *testing.T) {
+
+ // First verify non-panic behaviour
+ var buf Buffer
+ i, err := buf.ReadFrom(panicReader{})
+ if err != nil {
+ t.Fatal(err)
+ }
+ if i != 0 {
+ t.Fatalf("unexpected return from bytes.ReadFrom (1): got: %d, want %d", i, 0)
+ }
+ check(t, "TestReadFromPanicReader (1)", &buf, "")
+
+ // Confirm that when Reader panics, the empty buffer remains empty
+ var buf2 Buffer
+ defer func() {
+ recover()
+ check(t, "TestReadFromPanicReader (2)", &buf2, "")
+ }()
+ buf2.ReadFrom(panicReader{panic: true})
+}
+
+func TestReadFromNegativeReader(t *testing.T) {
+ var b Buffer
+ defer func() {
+ switch err := recover().(type) {
+ case nil:
+ t.Fatal("bytes.Buffer.ReadFrom didn't panic")
+ case error:
+ // this is the error string of errNegativeRead
+ wantError := "bytes.Buffer: reader returned negative count from Read"
+ if err.Error() != wantError {
+ t.Fatalf("recovered panic: got %v, want %v", err.Error(), wantError)
+ }
+ default:
+ t.Fatalf("unexpected panic value: %#v", err)
+ }
+ }()
+
+ b.ReadFrom(new(negativeReader))
+}
+
+func TestWriteTo(t *testing.T) {
+ var buf Buffer
+ for i := 3; i < 30; i += 3 {
+ s := fillBytes(t, "TestWriteTo (1)", &buf, "", 5, testBytes[:len(testBytes)/i])
+ var b Buffer
+ buf.WriteTo(&b)
+ empty(t, "TestWriteTo (2)", &b, s, make([]byte, len(testString)))
+ }
+}
+
+func TestWriteAppend(t *testing.T) {
+ var got Buffer
+ var want []byte
+ for i := 0; i < 1000; i++ {
+ b := got.AvailableBuffer()
+ b = strconv.AppendInt(b, int64(i), 10)
+ want = strconv.AppendInt(want, int64(i), 10)
+ got.Write(b)
+ }
+ if !Equal(got.Bytes(), want) {
+ t.Fatalf("Bytes() = %q, want %q", &got, want)
+ }
+
+ // With a sufficiently sized buffer, there should be no allocations.
+ n := testing.AllocsPerRun(100, func() {
+ got.Reset()
+ for i := 0; i < 1000; i++ {
+ b := got.AvailableBuffer()
+ b = strconv.AppendInt(b, int64(i), 10)
+ got.Write(b)
+ }
+ })
+ if n > 0 {
+ t.Errorf("allocations occurred while appending")
+ }
+}
+
+func TestRuneIO(t *testing.T) {
+ const NRune = 1000
+ // Built a test slice while we write the data
+ b := make([]byte, utf8.UTFMax*NRune)
+ var buf Buffer
+ n := 0
+ for r := rune(0); r < NRune; r++ {
+ size := utf8.EncodeRune(b[n:], r)
+ nbytes, err := buf.WriteRune(r)
+ if err != nil {
+ t.Fatalf("WriteRune(%U) error: %s", r, err)
+ }
+ if nbytes != size {
+ t.Fatalf("WriteRune(%U) expected %d, got %d", r, size, nbytes)
+ }
+ n += size
+ }
+ b = b[0:n]
+
+ // Check the resulting bytes
+ if !Equal(buf.Bytes(), b) {
+ t.Fatalf("incorrect result from WriteRune: %q not %q", buf.Bytes(), b)
+ }
+
+ p := make([]byte, utf8.UTFMax)
+ // Read it back with ReadRune
+ for r := rune(0); r < NRune; r++ {
+ size := utf8.EncodeRune(p, r)
+ nr, nbytes, err := buf.ReadRune()
+ if nr != r || nbytes != size || err != nil {
+ t.Fatalf("ReadRune(%U) got %U,%d not %U,%d (err=%s)", r, nr, nbytes, r, size, err)
+ }
+ }
+
+ // Check that UnreadRune works
+ buf.Reset()
+
+ // check at EOF
+ if err := buf.UnreadRune(); err == nil {
+ t.Fatal("UnreadRune at EOF: got no error")
+ }
+ if _, _, err := buf.ReadRune(); err == nil {
+ t.Fatal("ReadRune at EOF: got no error")
+ }
+ if err := buf.UnreadRune(); err == nil {
+ t.Fatal("UnreadRune after ReadRune at EOF: got no error")
+ }
+
+ // check not at EOF
+ buf.Write(b)
+ for r := rune(0); r < NRune; r++ {
+ r1, size, _ := buf.ReadRune()
+ if err := buf.UnreadRune(); err != nil {
+ t.Fatalf("UnreadRune(%U) got error %q", r, err)
+ }
+ r2, nbytes, err := buf.ReadRune()
+ if r1 != r2 || r1 != r || nbytes != size || err != nil {
+ t.Fatalf("ReadRune(%U) after UnreadRune got %U,%d not %U,%d (err=%s)", r, r2, nbytes, r, size, err)
+ }
+ }
+}
+
+func TestWriteInvalidRune(t *testing.T) {
+ // Invalid runes, including negative ones, should be written as
+ // utf8.RuneError.
+ for _, r := range []rune{-1, utf8.MaxRune + 1} {
+ var buf Buffer
+ buf.WriteRune(r)
+ check(t, fmt.Sprintf("TestWriteInvalidRune (%d)", r), &buf, "\uFFFD")
+ }
+}
+
+func TestNext(t *testing.T) {
+ b := []byte{0, 1, 2, 3, 4}
+ tmp := make([]byte, 5)
+ for i := 0; i <= 5; i++ {
+ for j := i; j <= 5; j++ {
+ for k := 0; k <= 6; k++ {
+ // 0 <= i <= j <= 5; 0 <= k <= 6
+ // Check that if we start with a buffer
+ // of length j at offset i and ask for
+ // Next(k), we get the right bytes.
+ buf := NewBuffer(b[0:j])
+ n, _ := buf.Read(tmp[0:i])
+ if n != i {
+ t.Fatalf("Read %d returned %d", i, n)
+ }
+ bb := buf.Next(k)
+ want := k
+ if want > j-i {
+ want = j - i
+ }
+ if len(bb) != want {
+ t.Fatalf("in %d,%d: len(Next(%d)) == %d", i, j, k, len(bb))
+ }
+ for l, v := range bb {
+ if v != byte(l+i) {
+ t.Fatalf("in %d,%d: Next(%d)[%d] = %d, want %d", i, j, k, l, v, l+i)
+ }
+ }
+ }
+ }
+ }
+}
+
+var readBytesTests = []struct {
+ buffer string
+ delim byte
+ expected []string
+ err error
+}{
+ {"", 0, []string{""}, io.EOF},
+ {"a\x00", 0, []string{"a\x00"}, nil},
+ {"abbbaaaba", 'b', []string{"ab", "b", "b", "aaab"}, nil},
+ {"hello\x01world", 1, []string{"hello\x01"}, nil},
+ {"foo\nbar", 0, []string{"foo\nbar"}, io.EOF},
+ {"alpha\nbeta\ngamma\n", '\n', []string{"alpha\n", "beta\n", "gamma\n"}, nil},
+ {"alpha\nbeta\ngamma", '\n', []string{"alpha\n", "beta\n", "gamma"}, io.EOF},
+}
+
+func TestReadBytes(t *testing.T) {
+ for _, test := range readBytesTests {
+ buf := NewBufferString(test.buffer)
+ var err error
+ for _, expected := range test.expected {
+ var bytes []byte
+ bytes, err = buf.ReadBytes(test.delim)
+ if string(bytes) != expected {
+ t.Errorf("expected %q, got %q", expected, bytes)
+ }
+ if err != nil {
+ break
+ }
+ }
+ if err != test.err {
+ t.Errorf("expected error %v, got %v", test.err, err)
+ }
+ }
+}
+
+func TestReadString(t *testing.T) {
+ for _, test := range readBytesTests {
+ buf := NewBufferString(test.buffer)
+ var err error
+ for _, expected := range test.expected {
+ var s string
+ s, err = buf.ReadString(test.delim)
+ if s != expected {
+ t.Errorf("expected %q, got %q", expected, s)
+ }
+ if err != nil {
+ break
+ }
+ }
+ if err != test.err {
+ t.Errorf("expected error %v, got %v", test.err, err)
+ }
+ }
+}
+
+var peekTests = []struct {
+ buffer string
+ skip int
+ n int
+ expected string
+ err error
+}{
+ {"", 0, 0, "", nil},
+ {"aaa", 0, 3, "aaa", nil},
+ {"foobar", 0, 2, "fo", nil},
+ {"a", 0, 2, "a", io.EOF},
+ {"helloworld", 4, 3, "owo", nil},
+ {"helloworld", 5, 5, "world", nil},
+ {"helloworld", 5, 6, "world", io.EOF},
+ {"helloworld", 10, 1, "", io.EOF},
+}
+
+func TestPeek(t *testing.T) {
+ for _, test := range peekTests {
+ buf := NewBufferString(test.buffer)
+ buf.Next(test.skip)
+ bytes, err := buf.Peek(test.n)
+ if string(bytes) != test.expected {
+ t.Errorf("expected %q, got %q", test.expected, bytes)
+ }
+ if err != test.err {
+ t.Errorf("expected error %v, got %v", test.err, err)
+ }
+ if buf.Len() != len(test.buffer)-test.skip {
+ t.Errorf("bad length after peek: %d, want %d", buf.Len(), len(test.buffer)-test.skip)
+ }
+ }
+}
+
+func BenchmarkReadString(b *testing.B) {
+ const n = 32 << 10
+
+ data := make([]byte, n)
+ data[n-1] = 'x'
+ b.SetBytes(int64(n))
+ for i := 0; i < b.N; i++ {
+ buf := NewBuffer(data)
+ _, err := buf.ReadString('x')
+ if err != nil {
+ b.Fatal(err)
+ }
+ }
+}
+
+func TestGrow(t *testing.T) {
+ x := []byte{'x'}
+ y := []byte{'y'}
+ tmp := make([]byte, 72)
+ for _, growLen := range []int{0, 100, 1000, 10000, 100000} {
+ for _, startLen := range []int{0, 100, 1000, 10000, 100000} {
+ xBytes := Repeat(x, startLen)
+
+ buf := NewBuffer(xBytes)
+ // If we read, this affects buf.off, which is good to test.
+ readBytes, _ := buf.Read(tmp)
+ yBytes := Repeat(y, growLen)
+ allocs := testing.AllocsPerRun(100, func() {
+ buf.Grow(growLen)
+ buf.Write(yBytes)
+ })
+ // Check no allocation occurs in write, as long as we're single-threaded.
+ if allocs != 0 {
+ t.Errorf("allocation occurred during write")
+ }
+ // Check that buffer has correct data.
+ if !Equal(buf.Bytes()[0:startLen-readBytes], xBytes[readBytes:]) {
+ t.Errorf("bad initial data at %d %d", startLen, growLen)
+ }
+ if !Equal(buf.Bytes()[startLen-readBytes:startLen-readBytes+growLen], yBytes) {
+ t.Errorf("bad written data at %d %d", startLen, growLen)
+ }
+ }
+ }
+}
+
+func TestGrowOverflow(t *testing.T) {
+ defer func() {
+ if err := recover(); err != ErrTooLarge {
+ t.Errorf("after too-large Grow, recover() = %v; want %v", err, ErrTooLarge)
+ }
+ }()
+
+ buf := NewBuffer(make([]byte, 1))
+ const maxInt = int(^uint(0) >> 1)
+ buf.Grow(maxInt)
+}
+
+// Was a bug: used to give EOF reading empty slice at EOF.
+func TestReadEmptyAtEOF(t *testing.T) {
+ b := new(Buffer)
+ slice := make([]byte, 0)
+ n, err := b.Read(slice)
+ if err != nil {
+ t.Errorf("read error: %v", err)
+ }
+ if n != 0 {
+ t.Errorf("wrong count; got %d want 0", n)
+ }
+}
+
+func TestUnreadByte(t *testing.T) {
+ b := new(Buffer)
+
+ // check at EOF
+ if err := b.UnreadByte(); err == nil {
+ t.Fatal("UnreadByte at EOF: got no error")
+ }
+ if _, err := b.ReadByte(); err == nil {
+ t.Fatal("ReadByte at EOF: got no error")
+ }
+ if err := b.UnreadByte(); err == nil {
+ t.Fatal("UnreadByte after ReadByte at EOF: got no error")
+ }
+
+ // check not at EOF
+ b.WriteString("abcdefghijklmnopqrstuvwxyz")
+
+ // after unsuccessful read
+ if n, err := b.Read(nil); n != 0 || err != nil {
+ t.Fatalf("Read(nil) = %d,%v; want 0,nil", n, err)
+ }
+ if err := b.UnreadByte(); err == nil {
+ t.Fatal("UnreadByte after Read(nil): got no error")
+ }
+
+ // after successful read
+ if _, err := b.ReadBytes('m'); err != nil {
+ t.Fatalf("ReadBytes: %v", err)
+ }
+ if err := b.UnreadByte(); err != nil {
+ t.Fatalf("UnreadByte: %v", err)
+ }
+ c, err := b.ReadByte()
+ if err != nil {
+ t.Fatalf("ReadByte: %v", err)
+ }
+ if c != 'm' {
+ t.Errorf("ReadByte = %q; want %q", c, 'm')
+ }
+}
+
+// Tests that we occasionally compact. Issue 5154.
+func TestBufferGrowth(t *testing.T) {
+ var b Buffer
+ buf := make([]byte, 1024)
+ b.Write(buf[0:1])
+ var cap0 int
+ for i := 0; i < 5<<10; i++ {
+ b.Write(buf)
+ b.Read(buf)
+ if i == 0 {
+ cap0 = b.Cap()
+ }
+ }
+ cap1 := b.Cap()
+ // (*Buffer).grow allows for 2x capacity slop before sliding,
+ // so set our error threshold at 3x.
+ if cap1 > cap0*3 {
+ t.Errorf("buffer cap = %d; too big (grew from %d)", cap1, cap0)
+ }
+}
+
+func BenchmarkWriteByte(b *testing.B) {
+ const n = 4 << 10
+ b.SetBytes(n)
+ buf := NewBuffer(make([]byte, n))
+ for i := 0; i < b.N; i++ {
+ buf.Reset()
+ for i := 0; i < n; i++ {
+ buf.WriteByte('x')
+ }
+ }
+}
+
+func BenchmarkWriteRune(b *testing.B) {
+ const n = 4 << 10
+ const r = '☺'
+ b.SetBytes(int64(n * utf8.RuneLen(r)))
+ buf := NewBuffer(make([]byte, n*utf8.UTFMax))
+ for i := 0; i < b.N; i++ {
+ buf.Reset()
+ for i := 0; i < n; i++ {
+ buf.WriteRune(r)
+ }
+ }
+}
+
+// From Issue 5154.
+func BenchmarkBufferNotEmptyWriteRead(b *testing.B) {
+ buf := make([]byte, 1024)
+ for i := 0; i < b.N; i++ {
+ var b Buffer
+ b.Write(buf[0:1])
+ for i := 0; i < 5<<10; i++ {
+ b.Write(buf)
+ b.Read(buf)
+ }
+ }
+}
+
+// Check that we don't compact too often. From Issue 5154.
+func BenchmarkBufferFullSmallReads(b *testing.B) {
+ buf := make([]byte, 1024)
+ for i := 0; i < b.N; i++ {
+ var b Buffer
+ b.Write(buf)
+ for b.Len()+20 < b.Cap() {
+ b.Write(buf[:10])
+ }
+ for i := 0; i < 5<<10; i++ {
+ b.Read(buf[:1])
+ b.Write(buf[:1])
+ }
+ }
+}
+
+func BenchmarkBufferWriteBlock(b *testing.B) {
+ block := make([]byte, 1024)
+ for _, n := range []int{1 << 12, 1 << 16, 1 << 20} {
+ b.Run(fmt.Sprintf("N%d", n), func(b *testing.B) {
+ b.ReportAllocs()
+ for i := 0; i < b.N; i++ {
+ var bb Buffer
+ for bb.Len() < n {
+ bb.Write(block)
+ }
+ }
+ })
+ }
+}
+
+func BenchmarkBufferAppendNoCopy(b *testing.B) {
+ var bb Buffer
+ bb.Grow(16 << 20)
+ b.SetBytes(int64(bb.Available()))
+ b.ReportAllocs()
+ for i := 0; i < b.N; i++ {
+ bb.Reset()
+ b := bb.AvailableBuffer()
+ b = b[:cap(b)] // use max capacity to simulate a large append operation
+ bb.Write(b) // should be nearly infinitely fast
+ }
+}
diff --git a/go/src/bytes/bytes.go b/go/src/bytes/bytes.go
new file mode 100644
index 0000000000000000000000000000000000000000..87183c01955829a05b0bcde67757af945244ff1f
--- /dev/null
+++ b/go/src/bytes/bytes.go
@@ -0,0 +1,1415 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package bytes implements functions for the manipulation of byte slices.
+// It is analogous to the facilities of the [strings] package.
+package bytes
+
+import (
+ "internal/bytealg"
+ "math/bits"
+ "unicode"
+ "unicode/utf8"
+ _ "unsafe" // for linkname
+)
+
+// Equal reports whether a and b
+// are the same length and contain the same bytes.
+// A nil argument is equivalent to an empty slice.
+func Equal(a, b []byte) bool {
+ // Neither cmd/compile nor gccgo allocates for these string conversions.
+ return string(a) == string(b)
+}
+
+// Compare returns an integer comparing two byte slices lexicographically.
+// The result will be 0 if a == b, -1 if a < b, and +1 if a > b.
+// A nil argument is equivalent to an empty slice.
+func Compare(a, b []byte) int {
+ return bytealg.Compare(a, b)
+}
+
+// explode splits s into a slice of UTF-8 sequences, one per Unicode code point (still slices of bytes),
+// up to a maximum of n byte slices. Invalid UTF-8 sequences are chopped into individual bytes.
+func explode(s []byte, n int) [][]byte {
+ if n <= 0 || n > len(s) {
+ n = len(s)
+ }
+ a := make([][]byte, n)
+ var size int
+ na := 0
+ for len(s) > 0 {
+ if na+1 >= n {
+ a[na] = s
+ na++
+ break
+ }
+ _, size = utf8.DecodeRune(s)
+ a[na] = s[0:size:size]
+ s = s[size:]
+ na++
+ }
+ return a[0:na]
+}
+
+// Count counts the number of non-overlapping instances of sep in s.
+// If sep is an empty slice, Count returns 1 + the number of UTF-8-encoded code points in s.
+func Count(s, sep []byte) int {
+ // special case
+ if len(sep) == 0 {
+ return utf8.RuneCount(s) + 1
+ }
+ if len(sep) == 1 {
+ return bytealg.Count(s, sep[0])
+ }
+ n := 0
+ for {
+ i := Index(s, sep)
+ if i == -1 {
+ return n
+ }
+ n++
+ s = s[i+len(sep):]
+ }
+}
+
+// Contains reports whether subslice is within b.
+func Contains(b, subslice []byte) bool {
+ return Index(b, subslice) != -1
+}
+
+// ContainsAny reports whether any of the UTF-8-encoded code points in chars are within b.
+func ContainsAny(b []byte, chars string) bool {
+ return IndexAny(b, chars) >= 0
+}
+
+// ContainsRune reports whether the rune is contained in the UTF-8-encoded byte slice b.
+func ContainsRune(b []byte, r rune) bool {
+ return IndexRune(b, r) >= 0
+}
+
+// ContainsFunc reports whether any of the UTF-8-encoded code points r within b satisfy f(r).
+func ContainsFunc(b []byte, f func(rune) bool) bool {
+ return IndexFunc(b, f) >= 0
+}
+
+// IndexByte returns the index of the first instance of c in b, or -1 if c is not present in b.
+func IndexByte(b []byte, c byte) int {
+ return bytealg.IndexByte(b, c)
+}
+
+func indexBytePortable(s []byte, c byte) int {
+ for i, b := range s {
+ if b == c {
+ return i
+ }
+ }
+ return -1
+}
+
+// LastIndex returns the index of the last instance of sep in s, or -1 if sep is not present in s.
+func LastIndex(s, sep []byte) int {
+ n := len(sep)
+ switch {
+ case n == 0:
+ return len(s)
+ case n == 1:
+ return bytealg.LastIndexByte(s, sep[0])
+ case n == len(s):
+ if Equal(s, sep) {
+ return 0
+ }
+ return -1
+ case n > len(s):
+ return -1
+ }
+ return bytealg.LastIndexRabinKarp(s, sep)
+}
+
+// LastIndexByte returns the index of the last instance of c in s, or -1 if c is not present in s.
+func LastIndexByte(s []byte, c byte) int {
+ return bytealg.LastIndexByte(s, c)
+}
+
+// IndexRune interprets s as a sequence of UTF-8-encoded code points.
+// It returns the byte index of the first occurrence in s of the given rune.
+// It returns -1 if rune is not present in s.
+// If r is [utf8.RuneError], it returns the first instance of any
+// invalid UTF-8 byte sequence.
+func IndexRune(s []byte, r rune) int {
+ const haveFastIndex = bytealg.MaxBruteForce > 0
+ switch {
+ case 0 <= r && r < utf8.RuneSelf:
+ return IndexByte(s, byte(r))
+ case r == utf8.RuneError:
+ for i := 0; i < len(s); {
+ r1, n := utf8.DecodeRune(s[i:])
+ if r1 == utf8.RuneError {
+ return i
+ }
+ i += n
+ }
+ return -1
+ case !utf8.ValidRune(r):
+ return -1
+ default:
+ // Search for rune r using the last byte of its UTF-8 encoded form.
+ // The distribution of the last byte is more uniform compared to the
+ // first byte which has a 78% chance of being [240, 243, 244].
+ var b [utf8.UTFMax]byte
+ n := utf8.EncodeRune(b[:], r)
+ last := n - 1
+ i := last
+ fails := 0
+ for i < len(s) {
+ if s[i] != b[last] {
+ o := IndexByte(s[i+1:], b[last])
+ if o < 0 {
+ return -1
+ }
+ i += o + 1
+ }
+ // Step backwards comparing bytes.
+ for j := 1; j < n; j++ {
+ if s[i-j] != b[last-j] {
+ goto next
+ }
+ }
+ return i - last
+ next:
+ fails++
+ i++
+ if (haveFastIndex && fails > bytealg.Cutover(i)) && i < len(s) ||
+ (!haveFastIndex && fails >= 4+i>>4 && i < len(s)) {
+ goto fallback
+ }
+ }
+ return -1
+
+ fallback:
+ // Switch to bytealg.Index, if available, or a brute force search when
+ // IndexByte returns too many false positives.
+ if haveFastIndex {
+ if j := bytealg.Index(s[i-last:], b[:n]); j >= 0 {
+ return i + j - last
+ }
+ } else {
+ // If bytealg.Index is not available a brute force search is
+ // ~1.5-3x faster than Rabin-Karp since n is small.
+ c0 := b[last]
+ c1 := b[last-1] // There are at least 2 chars to match
+ loop:
+ for ; i < len(s); i++ {
+ if s[i] == c0 && s[i-1] == c1 {
+ for k := 2; k < n; k++ {
+ if s[i-k] != b[last-k] {
+ continue loop
+ }
+ }
+ return i - last
+ }
+ }
+ }
+ return -1
+ }
+}
+
+// IndexAny interprets s as a sequence of UTF-8-encoded Unicode code points.
+// It returns the byte index of the first occurrence in s of any of the Unicode
+// code points in chars. It returns -1 if chars is empty or if there is no code
+// point in common.
+func IndexAny(s []byte, chars string) int {
+ if chars == "" {
+ // Avoid scanning all of s.
+ return -1
+ }
+ if len(s) == 1 {
+ r := rune(s[0])
+ if r >= utf8.RuneSelf {
+ // search utf8.RuneError.
+ for _, r = range chars {
+ if r == utf8.RuneError {
+ return 0
+ }
+ }
+ return -1
+ }
+ if bytealg.IndexByteString(chars, s[0]) >= 0 {
+ return 0
+ }
+ return -1
+ }
+ if len(chars) == 1 {
+ r := rune(chars[0])
+ if r >= utf8.RuneSelf {
+ r = utf8.RuneError
+ }
+ return IndexRune(s, r)
+ }
+ if len(s) > 8 {
+ if as, isASCII := makeASCIISet(chars); isASCII {
+ for i, c := range s {
+ if as.contains(c) {
+ return i
+ }
+ }
+ return -1
+ }
+ }
+ var width int
+ for i := 0; i < len(s); i += width {
+ r := rune(s[i])
+ if r < utf8.RuneSelf {
+ if bytealg.IndexByteString(chars, s[i]) >= 0 {
+ return i
+ }
+ width = 1
+ continue
+ }
+ r, width = utf8.DecodeRune(s[i:])
+ if r != utf8.RuneError {
+ // r is 2 to 4 bytes
+ if len(chars) == width {
+ if chars == string(r) {
+ return i
+ }
+ continue
+ }
+ // Use bytealg.IndexString for performance if available.
+ if bytealg.MaxLen >= width {
+ if bytealg.IndexString(chars, string(r)) >= 0 {
+ return i
+ }
+ continue
+ }
+ }
+ for _, ch := range chars {
+ if r == ch {
+ return i
+ }
+ }
+ }
+ return -1
+}
+
+// LastIndexAny interprets s as a sequence of UTF-8-encoded Unicode code
+// points. It returns the byte index of the last occurrence in s of any of
+// the Unicode code points in chars. It returns -1 if chars is empty or if
+// there is no code point in common.
+func LastIndexAny(s []byte, chars string) int {
+ if chars == "" {
+ // Avoid scanning all of s.
+ return -1
+ }
+ if len(s) > 8 {
+ if as, isASCII := makeASCIISet(chars); isASCII {
+ for i := len(s) - 1; i >= 0; i-- {
+ if as.contains(s[i]) {
+ return i
+ }
+ }
+ return -1
+ }
+ }
+ if len(s) == 1 {
+ r := rune(s[0])
+ if r >= utf8.RuneSelf {
+ for _, r = range chars {
+ if r == utf8.RuneError {
+ return 0
+ }
+ }
+ return -1
+ }
+ if bytealg.IndexByteString(chars, s[0]) >= 0 {
+ return 0
+ }
+ return -1
+ }
+ if len(chars) == 1 {
+ cr := rune(chars[0])
+ if cr >= utf8.RuneSelf {
+ cr = utf8.RuneError
+ }
+ for i := len(s); i > 0; {
+ r, size := utf8.DecodeLastRune(s[:i])
+ i -= size
+ if r == cr {
+ return i
+ }
+ }
+ return -1
+ }
+ for i := len(s); i > 0; {
+ r := rune(s[i-1])
+ if r < utf8.RuneSelf {
+ if bytealg.IndexByteString(chars, s[i-1]) >= 0 {
+ return i - 1
+ }
+ i--
+ continue
+ }
+ r, size := utf8.DecodeLastRune(s[:i])
+ i -= size
+ if r != utf8.RuneError {
+ // r is 2 to 4 bytes
+ if len(chars) == size {
+ if chars == string(r) {
+ return i
+ }
+ continue
+ }
+ // Use bytealg.IndexString for performance if available.
+ if bytealg.MaxLen >= size {
+ if bytealg.IndexString(chars, string(r)) >= 0 {
+ return i
+ }
+ continue
+ }
+ }
+ for _, ch := range chars {
+ if r == ch {
+ return i
+ }
+ }
+ }
+ return -1
+}
+
+// Generic split: splits after each instance of sep,
+// including sepSave bytes of sep in the subslices.
+func genSplit(s, sep []byte, sepSave, n int) [][]byte {
+ if n == 0 {
+ return nil
+ }
+ if len(sep) == 0 {
+ return explode(s, n)
+ }
+ if n < 0 {
+ n = Count(s, sep) + 1
+ }
+ if n > len(s)+1 {
+ n = len(s) + 1
+ }
+
+ a := make([][]byte, n)
+ n--
+ i := 0
+ for i < n {
+ m := Index(s, sep)
+ if m < 0 {
+ break
+ }
+ a[i] = s[: m+sepSave : m+sepSave]
+ s = s[m+len(sep):]
+ i++
+ }
+ a[i] = s
+ return a[:i+1]
+}
+
+// SplitN slices s into subslices separated by sep and returns a slice of
+// the subslices between those separators.
+// If sep is empty, SplitN splits after each UTF-8 sequence.
+// The count determines the number of subslices to return:
+// - n > 0: at most n subslices; the last subslice will be the unsplit remainder;
+// - n == 0: the result is nil (zero subslices);
+// - n < 0: all subslices.
+//
+// To split around the first instance of a separator, see [Cut].
+func SplitN(s, sep []byte, n int) [][]byte { return genSplit(s, sep, 0, n) }
+
+// SplitAfterN slices s into subslices after each instance of sep and
+// returns a slice of those subslices.
+// If sep is empty, SplitAfterN splits after each UTF-8 sequence.
+// The count determines the number of subslices to return:
+// - n > 0: at most n subslices; the last subslice will be the unsplit remainder;
+// - n == 0: the result is nil (zero subslices);
+// - n < 0: all subslices.
+func SplitAfterN(s, sep []byte, n int) [][]byte {
+ return genSplit(s, sep, len(sep), n)
+}
+
+// Split slices s into all subslices separated by sep and returns a slice of
+// the subslices between those separators.
+// If sep is empty, Split splits after each UTF-8 sequence.
+// It is equivalent to SplitN with a count of -1.
+//
+// To split around the first instance of a separator, see [Cut].
+func Split(s, sep []byte) [][]byte { return genSplit(s, sep, 0, -1) }
+
+// SplitAfter slices s into all subslices after each instance of sep and
+// returns a slice of those subslices.
+// If sep is empty, SplitAfter splits after each UTF-8 sequence.
+// It is equivalent to SplitAfterN with a count of -1.
+func SplitAfter(s, sep []byte) [][]byte {
+ return genSplit(s, sep, len(sep), -1)
+}
+
+var asciiSpace = [256]uint8{'\t': 1, '\n': 1, '\v': 1, '\f': 1, '\r': 1, ' ': 1}
+
+// Fields interprets s as a sequence of UTF-8-encoded code points.
+// It splits the slice s around each instance of one or more consecutive white space
+// characters, as defined by [unicode.IsSpace], returning a slice of subslices of s or an
+// empty slice if s contains only white space. Every element of the returned slice is
+// non-empty. Unlike [Split], leading and trailing runs of white space characters
+// are discarded.
+func Fields(s []byte) [][]byte {
+ // First count the fields.
+ // This is an exact count if s is ASCII, otherwise it is an approximation.
+ n := 0
+ wasSpace := 1
+ // setBits is used to track which bits are set in the bytes of s.
+ setBits := uint8(0)
+ for i := 0; i < len(s); i++ {
+ r := s[i]
+ setBits |= r
+ isSpace := int(asciiSpace[r])
+ n += wasSpace & ^isSpace
+ wasSpace = isSpace
+ }
+
+ if setBits >= utf8.RuneSelf {
+ // Some runes in the input slice are not ASCII.
+ return FieldsFunc(s, unicode.IsSpace)
+ }
+
+ // ASCII fast path
+ a := make([][]byte, n)
+ na := 0
+ fieldStart := 0
+ i := 0
+ // Skip spaces in the front of the input.
+ for i < len(s) && asciiSpace[s[i]] != 0 {
+ i++
+ }
+ fieldStart = i
+ for i < len(s) {
+ if asciiSpace[s[i]] == 0 {
+ i++
+ continue
+ }
+ a[na] = s[fieldStart:i:i]
+ na++
+ i++
+ // Skip spaces in between fields.
+ for i < len(s) && asciiSpace[s[i]] != 0 {
+ i++
+ }
+ fieldStart = i
+ }
+ if fieldStart < len(s) { // Last field might end at EOF.
+ a[na] = s[fieldStart:len(s):len(s)]
+ }
+ return a
+}
+
+// FieldsFunc interprets s as a sequence of UTF-8-encoded code points.
+// It splits the slice s at each run of code points c satisfying f(c) and
+// returns a slice of subslices of s. If all code points in s satisfy f(c), or
+// len(s) == 0, an empty slice is returned. Every element of the returned slice is
+// non-empty. Unlike [Split], leading and trailing runs of code points
+// satisfying f(c) are discarded.
+//
+// FieldsFunc makes no guarantees about the order in which it calls f(c)
+// and assumes that f always returns the same value for a given c.
+func FieldsFunc(s []byte, f func(rune) bool) [][]byte {
+ // A span is used to record a slice of s of the form s[start:end].
+ // The start index is inclusive and the end index is exclusive.
+ type span struct {
+ start int
+ end int
+ }
+ spans := make([]span, 0, 32)
+
+ // Find the field start and end indices.
+ // Doing this in a separate pass (rather than slicing the string s
+ // and collecting the result substrings right away) is significantly
+ // more efficient, possibly due to cache effects.
+ start := -1 // valid span start if >= 0
+ for i := 0; i < len(s); {
+ r, size := utf8.DecodeRune(s[i:])
+ if f(r) {
+ if start >= 0 {
+ spans = append(spans, span{start, i})
+ start = -1
+ }
+ } else {
+ if start < 0 {
+ start = i
+ }
+ }
+ i += size
+ }
+
+ // Last field might end at EOF.
+ if start >= 0 {
+ spans = append(spans, span{start, len(s)})
+ }
+
+ // Create subslices from recorded field indices.
+ a := make([][]byte, len(spans))
+ for i, span := range spans {
+ a[i] = s[span.start:span.end:span.end]
+ }
+
+ return a
+}
+
+// Join concatenates the elements of s to create a new byte slice. The separator
+// sep is placed between elements in the resulting slice.
+func Join(s [][]byte, sep []byte) []byte {
+ if len(s) == 0 {
+ return []byte{}
+ }
+ if len(s) == 1 {
+ // Just return a copy.
+ return append([]byte(nil), s[0]...)
+ }
+
+ var n int
+ if len(sep) > 0 {
+ if len(sep) >= maxInt/(len(s)-1) {
+ panic("bytes: Join output length overflow")
+ }
+ n += len(sep) * (len(s) - 1)
+ }
+ for _, v := range s {
+ if len(v) > maxInt-n {
+ panic("bytes: Join output length overflow")
+ }
+ n += len(v)
+ }
+
+ b := bytealg.MakeNoZero(n)[:n:n]
+ bp := copy(b, s[0])
+ for _, v := range s[1:] {
+ bp += copy(b[bp:], sep)
+ bp += copy(b[bp:], v)
+ }
+ return b
+}
+
+// HasPrefix reports whether the byte slice s begins with prefix.
+func HasPrefix(s, prefix []byte) bool {
+ return len(s) >= len(prefix) && Equal(s[:len(prefix)], prefix)
+}
+
+// HasSuffix reports whether the byte slice s ends with suffix.
+func HasSuffix(s, suffix []byte) bool {
+ return len(s) >= len(suffix) && Equal(s[len(s)-len(suffix):], suffix)
+}
+
+// Map returns a copy of the byte slice s with all its characters modified
+// according to the mapping function. If mapping returns a negative value, the character is
+// dropped from the byte slice with no replacement. The characters in s and the
+// output are interpreted as UTF-8-encoded code points.
+func Map(mapping func(r rune) rune, s []byte) []byte {
+ // In the worst case, the slice can grow when mapped, making
+ // things unpleasant. But it's so rare we barge in assuming it's
+ // fine. It could also shrink but that falls out naturally.
+ b := make([]byte, 0, len(s))
+ for i := 0; i < len(s); {
+ r, wid := utf8.DecodeRune(s[i:])
+ r = mapping(r)
+ if r >= 0 {
+ b = utf8.AppendRune(b, r)
+ }
+ i += wid
+ }
+ return b
+}
+
+// Despite being an exported symbol,
+// Repeat is linknamed by widely used packages.
+// Notable members of the hall of shame include:
+// - gitee.com/quant1x/num
+//
+// Do not remove or change the type signature.
+// See go.dev/issue/67401.
+//
+// Note that this comment is not part of the doc comment.
+//
+//go:linkname Repeat
+
+// Repeat returns a new byte slice consisting of count copies of b.
+//
+// It panics if count is negative or if the result of (len(b) * count)
+// overflows.
+func Repeat(b []byte, count int) []byte {
+ if count == 0 {
+ return []byte{}
+ }
+
+ // Since we cannot return an error on overflow,
+ // we should panic if the repeat will generate an overflow.
+ // See golang.org/issue/16237.
+ if count < 0 {
+ panic("bytes: negative Repeat count")
+ }
+ hi, lo := bits.Mul(uint(len(b)), uint(count))
+ if hi > 0 || lo > uint(maxInt) {
+ panic("bytes: Repeat output length overflow")
+ }
+ n := int(lo) // lo = len(b) * count
+
+ if len(b) == 0 {
+ return []byte{}
+ }
+
+ // Past a certain chunk size it is counterproductive to use
+ // larger chunks as the source of the write, as when the source
+ // is too large we are basically just thrashing the CPU D-cache.
+ // So if the result length is larger than an empirically-found
+ // limit (8KB), we stop growing the source string once the limit
+ // is reached and keep reusing the same source string - that
+ // should therefore be always resident in the L1 cache - until we
+ // have completed the construction of the result.
+ // This yields significant speedups (up to +100%) in cases where
+ // the result length is large (roughly, over L2 cache size).
+ const chunkLimit = 8 * 1024
+ chunkMax := n
+ if chunkMax > chunkLimit {
+ chunkMax = chunkLimit / len(b) * len(b)
+ if chunkMax == 0 {
+ chunkMax = len(b)
+ }
+ }
+ nb := bytealg.MakeNoZero(n)[:n:n]
+ bp := copy(nb, b)
+ for bp < n {
+ chunk := min(bp, chunkMax)
+ bp += copy(nb[bp:], nb[:chunk])
+ }
+ return nb
+}
+
+// ToUpper returns a copy of the byte slice s with all Unicode letters mapped to
+// their upper case.
+func ToUpper(s []byte) []byte {
+ isASCII, hasLower := true, false
+ for i := 0; i < len(s); i++ {
+ c := s[i]
+ if c >= utf8.RuneSelf {
+ isASCII = false
+ break
+ }
+ hasLower = hasLower || ('a' <= c && c <= 'z')
+ }
+
+ if isASCII { // optimize for ASCII-only byte slices.
+ if !hasLower {
+ // Just return a copy.
+ return append([]byte(""), s...)
+ }
+ b := bytealg.MakeNoZero(len(s))[:len(s):len(s)]
+ for i := 0; i < len(s); i++ {
+ c := s[i]
+ if 'a' <= c && c <= 'z' {
+ c -= 'a' - 'A'
+ }
+ b[i] = c
+ }
+ return b
+ }
+ return Map(unicode.ToUpper, s)
+}
+
+// ToLower returns a copy of the byte slice s with all Unicode letters mapped to
+// their lower case.
+func ToLower(s []byte) []byte {
+ isASCII, hasUpper := true, false
+ for i := 0; i < len(s); i++ {
+ c := s[i]
+ if c >= utf8.RuneSelf {
+ isASCII = false
+ break
+ }
+ hasUpper = hasUpper || ('A' <= c && c <= 'Z')
+ }
+
+ if isASCII { // optimize for ASCII-only byte slices.
+ if !hasUpper {
+ return append([]byte(""), s...)
+ }
+ b := bytealg.MakeNoZero(len(s))[:len(s):len(s)]
+ for i := 0; i < len(s); i++ {
+ c := s[i]
+ if 'A' <= c && c <= 'Z' {
+ c += 'a' - 'A'
+ }
+ b[i] = c
+ }
+ return b
+ }
+ return Map(unicode.ToLower, s)
+}
+
+// ToTitle treats s as UTF-8-encoded bytes and returns a copy with all the Unicode letters mapped to their title case.
+func ToTitle(s []byte) []byte { return Map(unicode.ToTitle, s) }
+
+// ToUpperSpecial treats s as UTF-8-encoded bytes and returns a copy with all the Unicode letters mapped to their
+// upper case, giving priority to the special casing rules.
+func ToUpperSpecial(c unicode.SpecialCase, s []byte) []byte {
+ return Map(c.ToUpper, s)
+}
+
+// ToLowerSpecial treats s as UTF-8-encoded bytes and returns a copy with all the Unicode letters mapped to their
+// lower case, giving priority to the special casing rules.
+func ToLowerSpecial(c unicode.SpecialCase, s []byte) []byte {
+ return Map(c.ToLower, s)
+}
+
+// ToTitleSpecial treats s as UTF-8-encoded bytes and returns a copy with all the Unicode letters mapped to their
+// title case, giving priority to the special casing rules.
+func ToTitleSpecial(c unicode.SpecialCase, s []byte) []byte {
+ return Map(c.ToTitle, s)
+}
+
+// ToValidUTF8 treats s as UTF-8-encoded bytes and returns a copy with each run of bytes
+// representing invalid UTF-8 replaced with the bytes in replacement, which may be empty.
+func ToValidUTF8(s, replacement []byte) []byte {
+ b := make([]byte, 0, len(s)+len(replacement))
+ invalid := false // previous byte was from an invalid UTF-8 sequence
+ for i := 0; i < len(s); {
+ c := s[i]
+ if c < utf8.RuneSelf {
+ i++
+ invalid = false
+ b = append(b, c)
+ continue
+ }
+ _, wid := utf8.DecodeRune(s[i:])
+ if wid == 1 {
+ i++
+ if !invalid {
+ invalid = true
+ b = append(b, replacement...)
+ }
+ continue
+ }
+ invalid = false
+ b = append(b, s[i:i+wid]...)
+ i += wid
+ }
+ return b
+}
+
+// isSeparator reports whether the rune could mark a word boundary.
+// TODO: update when package unicode captures more of the properties.
+func isSeparator(r rune) bool {
+ // ASCII alphanumerics and underscore are not separators
+ if r <= 0x7F {
+ switch {
+ case '0' <= r && r <= '9':
+ return false
+ case 'a' <= r && r <= 'z':
+ return false
+ case 'A' <= r && r <= 'Z':
+ return false
+ case r == '_':
+ return false
+ }
+ return true
+ }
+ // Letters and digits are not separators
+ if unicode.IsLetter(r) || unicode.IsDigit(r) {
+ return false
+ }
+ // Otherwise, all we can do for now is treat spaces as separators.
+ return unicode.IsSpace(r)
+}
+
+// Title treats s as UTF-8-encoded bytes and returns a copy with all Unicode letters that begin
+// words mapped to their title case.
+//
+// Deprecated: The rule Title uses for word boundaries does not handle Unicode
+// punctuation properly. Use golang.org/x/text/cases instead.
+func Title(s []byte) []byte {
+ // Use a closure here to remember state.
+ // Hackish but effective. Depends on Map scanning in order and calling
+ // the closure once per rune.
+ prev := ' '
+ return Map(
+ func(r rune) rune {
+ if isSeparator(prev) {
+ prev = r
+ return unicode.ToTitle(r)
+ }
+ prev = r
+ return r
+ },
+ s)
+}
+
+// TrimLeftFunc treats s as UTF-8-encoded bytes and returns a subslice of s by slicing off
+// all leading UTF-8-encoded code points c that satisfy f(c).
+func TrimLeftFunc(s []byte, f func(r rune) bool) []byte {
+ i := indexFunc(s, f, false)
+ if i == -1 {
+ return nil
+ }
+ return s[i:]
+}
+
+// TrimRightFunc returns a subslice of s by slicing off all trailing
+// UTF-8-encoded code points c that satisfy f(c).
+func TrimRightFunc(s []byte, f func(r rune) bool) []byte {
+ i := lastIndexFunc(s, f, false)
+ if i >= 0 && s[i] >= utf8.RuneSelf {
+ _, wid := utf8.DecodeRune(s[i:])
+ i += wid
+ } else {
+ i++
+ }
+ return s[0:i]
+}
+
+// TrimFunc returns a subslice of s by slicing off all leading and trailing
+// UTF-8-encoded code points c that satisfy f(c).
+func TrimFunc(s []byte, f func(r rune) bool) []byte {
+ return TrimRightFunc(TrimLeftFunc(s, f), f)
+}
+
+// TrimPrefix returns s without the provided leading prefix string.
+// If s doesn't start with prefix, s is returned unchanged.
+func TrimPrefix(s, prefix []byte) []byte {
+ if HasPrefix(s, prefix) {
+ return s[len(prefix):]
+ }
+ return s
+}
+
+// TrimSuffix returns s without the provided trailing suffix string.
+// If s doesn't end with suffix, s is returned unchanged.
+func TrimSuffix(s, suffix []byte) []byte {
+ if HasSuffix(s, suffix) {
+ return s[:len(s)-len(suffix)]
+ }
+ return s
+}
+
+// IndexFunc interprets s as a sequence of UTF-8-encoded code points.
+// It returns the byte index in s of the first Unicode
+// code point satisfying f(c), or -1 if none do.
+func IndexFunc(s []byte, f func(r rune) bool) int {
+ return indexFunc(s, f, true)
+}
+
+// LastIndexFunc interprets s as a sequence of UTF-8-encoded code points.
+// It returns the byte index in s of the last Unicode
+// code point satisfying f(c), or -1 if none do.
+func LastIndexFunc(s []byte, f func(r rune) bool) int {
+ return lastIndexFunc(s, f, true)
+}
+
+// indexFunc is the same as IndexFunc except that if
+// truth==false, the sense of the predicate function is
+// inverted.
+func indexFunc(s []byte, f func(r rune) bool, truth bool) int {
+ start := 0
+ for start < len(s) {
+ r, wid := utf8.DecodeRune(s[start:])
+ if f(r) == truth {
+ return start
+ }
+ start += wid
+ }
+ return -1
+}
+
+// lastIndexFunc is the same as LastIndexFunc except that if
+// truth==false, the sense of the predicate function is
+// inverted.
+func lastIndexFunc(s []byte, f func(r rune) bool, truth bool) int {
+ for i := len(s); i > 0; {
+ r, size := rune(s[i-1]), 1
+ if r >= utf8.RuneSelf {
+ r, size = utf8.DecodeLastRune(s[0:i])
+ }
+ i -= size
+ if f(r) == truth {
+ return i
+ }
+ }
+ return -1
+}
+
+// asciiSet is a 32-byte value, where each bit represents the presence of a
+// given ASCII character in the set. The 128-bits of the lower 16 bytes,
+// starting with the least-significant bit of the lowest word to the
+// most-significant bit of the highest word, map to the full range of all
+// 128 ASCII characters. The 128-bits of the upper 16 bytes will be zeroed,
+// ensuring that any non-ASCII character will be reported as not in the set.
+// This allocates a total of 32 bytes even though the upper half
+// is unused to avoid bounds checks in asciiSet.contains.
+type asciiSet [8]uint32
+
+// makeASCIISet creates a set of ASCII characters and reports whether all
+// characters in chars are ASCII.
+func makeASCIISet(chars string) (as asciiSet, ok bool) {
+ for i := 0; i < len(chars); i++ {
+ c := chars[i]
+ if c >= utf8.RuneSelf {
+ return as, false
+ }
+ as[c/32] |= 1 << (c % 32)
+ }
+ return as, true
+}
+
+// contains reports whether c is inside the set.
+func (as *asciiSet) contains(c byte) bool {
+ return (as[c/32] & (1 << (c % 32))) != 0
+}
+
+// containsRune is a simplified version of strings.ContainsRune
+// to avoid importing the strings package.
+// We avoid bytes.ContainsRune to avoid allocating a temporary copy of s.
+func containsRune(s string, r rune) bool {
+ for _, c := range s {
+ if c == r {
+ return true
+ }
+ }
+ return false
+}
+
+// Trim returns a subslice of s by slicing off all leading and
+// trailing UTF-8-encoded code points contained in cutset.
+func Trim(s []byte, cutset string) []byte {
+ if len(s) == 0 {
+ // This is what we've historically done.
+ return nil
+ }
+ if cutset == "" {
+ return s
+ }
+ if len(cutset) == 1 && cutset[0] < utf8.RuneSelf {
+ return trimLeftByte(trimRightByte(s, cutset[0]), cutset[0])
+ }
+ if as, ok := makeASCIISet(cutset); ok {
+ return trimLeftASCII(trimRightASCII(s, &as), &as)
+ }
+ return trimLeftUnicode(trimRightUnicode(s, cutset), cutset)
+}
+
+// TrimLeft returns a subslice of s by slicing off all leading
+// UTF-8-encoded code points contained in cutset.
+func TrimLeft(s []byte, cutset string) []byte {
+ if len(s) == 0 {
+ // This is what we've historically done.
+ return nil
+ }
+ if cutset == "" {
+ return s
+ }
+ if len(cutset) == 1 && cutset[0] < utf8.RuneSelf {
+ return trimLeftByte(s, cutset[0])
+ }
+ if as, ok := makeASCIISet(cutset); ok {
+ return trimLeftASCII(s, &as)
+ }
+ return trimLeftUnicode(s, cutset)
+}
+
+func trimLeftByte(s []byte, c byte) []byte {
+ for len(s) > 0 && s[0] == c {
+ s = s[1:]
+ }
+ if len(s) == 0 {
+ // This is what we've historically done.
+ return nil
+ }
+ return s
+}
+
+func trimLeftASCII(s []byte, as *asciiSet) []byte {
+ for len(s) > 0 {
+ if !as.contains(s[0]) {
+ break
+ }
+ s = s[1:]
+ }
+ if len(s) == 0 {
+ // This is what we've historically done.
+ return nil
+ }
+ return s
+}
+
+func trimLeftUnicode(s []byte, cutset string) []byte {
+ for len(s) > 0 {
+ r, n := utf8.DecodeRune(s)
+ if !containsRune(cutset, r) {
+ break
+ }
+ s = s[n:]
+ }
+ if len(s) == 0 {
+ // This is what we've historically done.
+ return nil
+ }
+ return s
+}
+
+// TrimRight returns a subslice of s by slicing off all trailing
+// UTF-8-encoded code points that are contained in cutset.
+func TrimRight(s []byte, cutset string) []byte {
+ if len(s) == 0 || cutset == "" {
+ return s
+ }
+ if len(cutset) == 1 && cutset[0] < utf8.RuneSelf {
+ return trimRightByte(s, cutset[0])
+ }
+ if as, ok := makeASCIISet(cutset); ok {
+ return trimRightASCII(s, &as)
+ }
+ return trimRightUnicode(s, cutset)
+}
+
+func trimRightByte(s []byte, c byte) []byte {
+ for len(s) > 0 && s[len(s)-1] == c {
+ s = s[:len(s)-1]
+ }
+ return s
+}
+
+func trimRightASCII(s []byte, as *asciiSet) []byte {
+ for len(s) > 0 {
+ if !as.contains(s[len(s)-1]) {
+ break
+ }
+ s = s[:len(s)-1]
+ }
+ return s
+}
+
+func trimRightUnicode(s []byte, cutset string) []byte {
+ for len(s) > 0 {
+ r, n := rune(s[len(s)-1]), 1
+ if r >= utf8.RuneSelf {
+ r, n = utf8.DecodeLastRune(s)
+ }
+ if !containsRune(cutset, r) {
+ break
+ }
+ s = s[:len(s)-n]
+ }
+ return s
+}
+
+// TrimSpace returns a subslice of s by slicing off all leading and
+// trailing white space, as defined by Unicode.
+func TrimSpace(s []byte) []byte {
+ // Fast path for ASCII: look for the first ASCII non-space byte.
+ for lo, c := range s {
+ if c >= utf8.RuneSelf {
+ // If we run into a non-ASCII byte, fall back to the
+ // slower unicode-aware method on the remaining bytes.
+ return TrimFunc(s[lo:], unicode.IsSpace)
+ }
+ if asciiSpace[c] != 0 {
+ continue
+ }
+ s = s[lo:]
+ // Now look for the first ASCII non-space byte from the end.
+ for hi := len(s) - 1; hi >= 0; hi-- {
+ c := s[hi]
+ if c >= utf8.RuneSelf {
+ return TrimFunc(s[:hi+1], unicode.IsSpace)
+ }
+ if asciiSpace[c] == 0 {
+ // At this point, s[:hi+1] starts and ends with ASCII
+ // non-space bytes, so we're done. Non-ASCII cases have
+ // already been handled above.
+ return s[:hi+1]
+ }
+ }
+ }
+ // Special case to preserve previous TrimLeftFunc behavior,
+ // returning nil instead of empty slice if all spaces.
+ return nil
+}
+
+// Runes interprets s as a sequence of UTF-8-encoded code points.
+// It returns a slice of runes (Unicode code points) equivalent to s.
+func Runes(s []byte) []rune {
+ t := make([]rune, utf8.RuneCount(s))
+ i := 0
+ for len(s) > 0 {
+ r, l := utf8.DecodeRune(s)
+ t[i] = r
+ i++
+ s = s[l:]
+ }
+ return t
+}
+
+// Replace returns a copy of the slice s with the first n
+// non-overlapping instances of old replaced by new.
+// If old is empty, it matches at the beginning of the slice
+// and after each UTF-8 sequence, yielding up to k+1 replacements
+// for a k-rune slice.
+// If n < 0, there is no limit on the number of replacements.
+func Replace(s, old, new []byte, n int) []byte {
+ m := 0
+ if n != 0 {
+ // Compute number of replacements.
+ m = Count(s, old)
+ }
+ if m == 0 {
+ // Just return a copy.
+ return append([]byte(nil), s...)
+ }
+ if n < 0 || m < n {
+ n = m
+ }
+
+ // Apply replacements to buffer.
+ t := make([]byte, len(s)+n*(len(new)-len(old)))
+ w := 0
+ start := 0
+ if len(old) > 0 {
+ for range n {
+ j := start + Index(s[start:], old)
+ w += copy(t[w:], s[start:j])
+ w += copy(t[w:], new)
+ start = j + len(old)
+ }
+ } else { // len(old) == 0
+ w += copy(t[w:], new)
+ for range n - 1 {
+ _, wid := utf8.DecodeRune(s[start:])
+ j := start + wid
+ w += copy(t[w:], s[start:j])
+ w += copy(t[w:], new)
+ start = j
+ }
+ }
+ w += copy(t[w:], s[start:])
+ return t[0:w]
+}
+
+// ReplaceAll returns a copy of the slice s with all
+// non-overlapping instances of old replaced by new.
+// If old is empty, it matches at the beginning of the slice
+// and after each UTF-8 sequence, yielding up to k+1 replacements
+// for a k-rune slice.
+func ReplaceAll(s, old, new []byte) []byte {
+ return Replace(s, old, new, -1)
+}
+
+// EqualFold reports whether s and t, interpreted as UTF-8 strings,
+// are equal under simple Unicode case-folding, which is a more general
+// form of case-insensitivity.
+func EqualFold(s, t []byte) bool {
+ // ASCII fast path
+ i := 0
+ for n := min(len(s), len(t)); i < n; i++ {
+ sr := s[i]
+ tr := t[i]
+ if sr|tr >= utf8.RuneSelf {
+ goto hasUnicode
+ }
+
+ // Easy case.
+ if tr == sr {
+ continue
+ }
+
+ // Make sr < tr to simplify what follows.
+ if tr < sr {
+ tr, sr = sr, tr
+ }
+ // ASCII only, sr/tr must be upper/lower case
+ if 'A' <= sr && sr <= 'Z' && tr == sr+'a'-'A' {
+ continue
+ }
+ return false
+ }
+ // Check if we've exhausted both strings.
+ return len(s) == len(t)
+
+hasUnicode:
+ s = s[i:]
+ t = t[i:]
+ for len(s) != 0 && len(t) != 0 {
+ // Extract first rune from each.
+ sr, size := utf8.DecodeRune(s)
+ s = s[size:]
+ tr, size := utf8.DecodeRune(t)
+ t = t[size:]
+
+ // If they match, keep going; if not, return false.
+
+ // Easy case.
+ if tr == sr {
+ continue
+ }
+
+ // Make sr < tr to simplify what follows.
+ if tr < sr {
+ tr, sr = sr, tr
+ }
+ // Fast check for ASCII.
+ if tr < utf8.RuneSelf {
+ // ASCII only, sr/tr must be upper/lower case
+ if 'A' <= sr && sr <= 'Z' && tr == sr+'a'-'A' {
+ continue
+ }
+ return false
+ }
+
+ // General case. SimpleFold(x) returns the next equivalent rune > x
+ // or wraps around to smaller values.
+ r := unicode.SimpleFold(sr)
+ for r != sr && r < tr {
+ r = unicode.SimpleFold(r)
+ }
+ if r == tr {
+ continue
+ }
+ return false
+ }
+
+ // One string is empty. Are both?
+ return len(s) == len(t)
+}
+
+// Index returns the index of the first instance of sep in s, or -1 if sep is not present in s.
+func Index(s, sep []byte) int {
+ n := len(sep)
+ switch {
+ case n == 0:
+ return 0
+ case n == 1:
+ return IndexByte(s, sep[0])
+ case n == len(s):
+ if Equal(sep, s) {
+ return 0
+ }
+ return -1
+ case n > len(s):
+ return -1
+ case n <= bytealg.MaxLen:
+ // Use brute force when s and sep both are small
+ if len(s) <= bytealg.MaxBruteForce {
+ return bytealg.Index(s, sep)
+ }
+ c0 := sep[0]
+ c1 := sep[1]
+ i := 0
+ t := len(s) - n + 1
+ fails := 0
+ for i < t {
+ if s[i] != c0 {
+ // IndexByte is faster than bytealg.Index, so use it as long as
+ // we're not getting lots of false positives.
+ o := IndexByte(s[i+1:t], c0)
+ if o < 0 {
+ return -1
+ }
+ i += o + 1
+ }
+ if s[i+1] == c1 && Equal(s[i:i+n], sep) {
+ return i
+ }
+ fails++
+ i++
+ // Switch to bytealg.Index when IndexByte produces too many false positives.
+ if fails > bytealg.Cutover(i) {
+ r := bytealg.Index(s[i:], sep)
+ if r >= 0 {
+ return r + i
+ }
+ return -1
+ }
+ }
+ return -1
+ }
+ c0 := sep[0]
+ c1 := sep[1]
+ i := 0
+ fails := 0
+ t := len(s) - n + 1
+ for i < t {
+ if s[i] != c0 {
+ o := IndexByte(s[i+1:t], c0)
+ if o < 0 {
+ break
+ }
+ i += o + 1
+ }
+ if s[i+1] == c1 && Equal(s[i:i+n], sep) {
+ return i
+ }
+ i++
+ fails++
+ if fails >= 4+i>>4 && i < t {
+ // Give up on IndexByte, it isn't skipping ahead
+ // far enough to be better than Rabin-Karp.
+ // Experiments (using IndexPeriodic) suggest
+ // the cutover is about 16 byte skips.
+ // TODO: if large prefixes of sep are matching
+ // we should cutover at even larger average skips,
+ // because Equal becomes that much more expensive.
+ // This code does not take that effect into account.
+ j := bytealg.IndexRabinKarp(s[i:], sep)
+ if j < 0 {
+ return -1
+ }
+ return i + j
+ }
+ }
+ return -1
+}
+
+// Cut slices s around the first instance of sep,
+// returning the text before and after sep.
+// The found result reports whether sep appears in s.
+// If sep does not appear in s, cut returns s, nil, false.
+//
+// Cut returns slices of the original slice s, not copies.
+func Cut(s, sep []byte) (before, after []byte, found bool) {
+ if i := Index(s, sep); i >= 0 {
+ return s[:i], s[i+len(sep):], true
+ }
+ return s, nil, false
+}
+
+// Clone returns a copy of b[:len(b)].
+// The result may have additional unused capacity.
+// Clone(nil) returns nil.
+func Clone(b []byte) []byte {
+ if b == nil {
+ return nil
+ }
+ return append([]byte{}, b...)
+}
+
+// CutPrefix returns s without the provided leading prefix byte slice
+// and reports whether it found the prefix.
+// If s doesn't start with prefix, CutPrefix returns s, false.
+// If prefix is the empty byte slice, CutPrefix returns s, true.
+//
+// CutPrefix returns slices of the original slice s, not copies.
+func CutPrefix(s, prefix []byte) (after []byte, found bool) {
+ if !HasPrefix(s, prefix) {
+ return s, false
+ }
+ return s[len(prefix):], true
+}
+
+// CutSuffix returns s without the provided ending suffix byte slice
+// and reports whether it found the suffix.
+// If s doesn't end with suffix, CutSuffix returns s, false.
+// If suffix is the empty byte slice, CutSuffix returns s, true.
+//
+// CutSuffix returns slices of the original slice s, not copies.
+func CutSuffix(s, suffix []byte) (before []byte, found bool) {
+ if !HasSuffix(s, suffix) {
+ return s, false
+ }
+ return s[:len(s)-len(suffix)], true
+}
diff --git a/go/src/bytes/bytes_js_wasm_test.go b/go/src/bytes/bytes_js_wasm_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..ad9db343184f99faee7b86b5c6ca14425d2c130b
--- /dev/null
+++ b/go/src/bytes/bytes_js_wasm_test.go
@@ -0,0 +1,21 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build js && wasm
+
+package bytes_test
+
+import (
+ "bytes"
+ "testing"
+)
+
+func TestIssue65571(t *testing.T) {
+ b := make([]byte, 1<<31+1)
+ b[1<<31] = 1
+ i := bytes.IndexByte(b, 1)
+ if i != 1<<31 {
+ t.Errorf("IndexByte(b, 1) = %d; want %d", i, 1<<31)
+ }
+}
diff --git a/go/src/bytes/bytes_test.go b/go/src/bytes/bytes_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..891aef2c8b89960899f9d4735420bfd0b24e3aae
--- /dev/null
+++ b/go/src/bytes/bytes_test.go
@@ -0,0 +1,2501 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bytes_test
+
+import (
+ . "bytes"
+ "fmt"
+ "internal/asan"
+ "internal/testenv"
+ "iter"
+ "math"
+ "math/rand"
+ "slices"
+ "strings"
+ "testing"
+ "unicode"
+ "unicode/utf8"
+ "unsafe"
+)
+
+func sliceOfString(s [][]byte) []string {
+ result := make([]string, len(s))
+ for i, v := range s {
+ result[i] = string(v)
+ }
+ return result
+}
+
+func collect(t *testing.T, seq iter.Seq[[]byte]) [][]byte {
+ out := slices.Collect(seq)
+ out1 := slices.Collect(seq)
+ if !slices.Equal(sliceOfString(out), sliceOfString(out1)) {
+ t.Fatalf("inconsistent seq:\n%s\n%s", out, out1)
+ }
+ return out
+}
+
+type LinesTest struct {
+ a string
+ b []string
+}
+
+var linesTests = []LinesTest{
+ {a: "abc\nabc\n", b: []string{"abc\n", "abc\n"}},
+ {a: "abc\r\nabc", b: []string{"abc\r\n", "abc"}},
+ {a: "abc\r\n", b: []string{"abc\r\n"}},
+ {a: "\nabc", b: []string{"\n", "abc"}},
+ {a: "\nabc\n\n", b: []string{"\n", "abc\n", "\n"}},
+}
+
+func TestLines(t *testing.T) {
+ for _, s := range linesTests {
+ result := sliceOfString(slices.Collect(Lines([]byte(s.a))))
+ if !slices.Equal(result, s.b) {
+ t.Errorf(`slices.Collect(Lines(%q)) = %q; want %q`, s.a, result, s.b)
+ }
+ }
+}
+
+// For ease of reading, the test cases use strings that are converted to byte
+// slices before invoking the functions.
+
+var abcd = "abcd"
+var faces = "☺☻☹"
+var commas = "1,2,3,4"
+var dots = "1....2....3....4"
+
+type BinOpTest struct {
+ a string
+ b string
+ i int
+}
+
+func TestEqual(t *testing.T) {
+ // Run the tests and check for allocation at the same time.
+ allocs := testing.AllocsPerRun(10, func() {
+ for _, tt := range compareTests {
+ eql := Equal(tt.a, tt.b)
+ if eql != (tt.i == 0) {
+ t.Errorf(`Equal(%q, %q) = %v`, tt.a, tt.b, eql)
+ }
+ }
+ })
+ if allocs > 0 {
+ t.Errorf("Equal allocated %v times", allocs)
+ }
+}
+
+func TestEqualExhaustive(t *testing.T) {
+ var size = 128
+ if testing.Short() {
+ size = 32
+ }
+ a := make([]byte, size)
+ b := make([]byte, size)
+ b_init := make([]byte, size)
+ // randomish but deterministic data
+ for i := 0; i < size; i++ {
+ a[i] = byte(17 * i)
+ b_init[i] = byte(23*i + 100)
+ }
+
+ for len := 0; len <= size; len++ {
+ for x := 0; x <= size-len; x++ {
+ for y := 0; y <= size-len; y++ {
+ copy(b, b_init)
+ copy(b[y:y+len], a[x:x+len])
+ if !Equal(a[x:x+len], b[y:y+len]) || !Equal(b[y:y+len], a[x:x+len]) {
+ t.Errorf("Equal(%d, %d, %d) = false", len, x, y)
+ }
+ }
+ }
+ }
+}
+
+// make sure Equal returns false for minimally different strings. The data
+// is all zeros except for a single one in one location.
+func TestNotEqual(t *testing.T) {
+ var size = 128
+ if testing.Short() {
+ size = 32
+ }
+ a := make([]byte, size)
+ b := make([]byte, size)
+
+ for len := 0; len <= size; len++ {
+ for x := 0; x <= size-len; x++ {
+ for y := 0; y <= size-len; y++ {
+ for diffpos := x; diffpos < x+len; diffpos++ {
+ a[diffpos] = 1
+ if Equal(a[x:x+len], b[y:y+len]) || Equal(b[y:y+len], a[x:x+len]) {
+ t.Errorf("NotEqual(%d, %d, %d, %d) = true", len, x, y, diffpos)
+ }
+ a[diffpos] = 0
+ }
+ }
+ }
+ }
+}
+
+var indexTests = []BinOpTest{
+ {"", "", 0},
+ {"", "a", -1},
+ {"", "foo", -1},
+ {"fo", "foo", -1},
+ {"foo", "baz", -1},
+ {"foo", "foo", 0},
+ {"oofofoofooo", "f", 2},
+ {"oofofoofooo", "foo", 4},
+ {"barfoobarfoo", "foo", 3},
+ {"foo", "", 0},
+ {"foo", "o", 1},
+ {"abcABCabc", "A", 3},
+ // cases with one byte strings - test IndexByte and special case in Index()
+ {"", "a", -1},
+ {"x", "a", -1},
+ {"x", "x", 0},
+ {"abc", "a", 0},
+ {"abc", "b", 1},
+ {"abc", "c", 2},
+ {"abc", "x", -1},
+ {"barfoobarfooyyyzzzyyyzzzyyyzzzyyyxxxzzzyyy", "x", 33},
+ {"fofofofooofoboo", "oo", 7},
+ {"fofofofofofoboo", "ob", 11},
+ {"fofofofofofoboo", "boo", 12},
+ {"fofofofofofoboo", "oboo", 11},
+ {"fofofofofoooboo", "fooo", 8},
+ {"fofofofofofoboo", "foboo", 10},
+ {"fofofofofofoboo", "fofob", 8},
+ {"fofofofofofofoffofoobarfoo", "foffof", 12},
+ {"fofofofofoofofoffofoobarfoo", "foffof", 13},
+ {"fofofofofofofoffofoobarfoo", "foffofo", 12},
+ {"fofofofofoofofoffofoobarfoo", "foffofo", 13},
+ {"fofofofofoofofoffofoobarfoo", "foffofoo", 13},
+ {"fofofofofofofoffofoobarfoo", "foffofoo", 12},
+ {"fofofofofoofofoffofoobarfoo", "foffofoob", 13},
+ {"fofofofofofofoffofoobarfoo", "foffofoob", 12},
+ {"fofofofofoofofoffofoobarfoo", "foffofooba", 13},
+ {"fofofofofofofoffofoobarfoo", "foffofooba", 12},
+ {"fofofofofoofofoffofoobarfoo", "foffofoobar", 13},
+ {"fofofofofofofoffofoobarfoo", "foffofoobar", 12},
+ {"fofofofofoofofoffofoobarfoo", "foffofoobarf", 13},
+ {"fofofofofofofoffofoobarfoo", "foffofoobarf", 12},
+ {"fofofofofoofofoffofoobarfoo", "foffofoobarfo", 13},
+ {"fofofofofofofoffofoobarfoo", "foffofoobarfo", 12},
+ {"fofofofofoofofoffofoobarfoo", "foffofoobarfoo", 13},
+ {"fofofofofofofoffofoobarfoo", "foffofoobarfoo", 12},
+ {"fofofofofoofofoffofoobarfoo", "ofoffofoobarfoo", 12},
+ {"fofofofofofofoffofoobarfoo", "ofoffofoobarfoo", 11},
+ {"fofofofofoofofoffofoobarfoo", "fofoffofoobarfoo", 11},
+ {"fofofofofofofoffofoobarfoo", "fofoffofoobarfoo", 10},
+ {"fofofofofoofofoffofoobarfoo", "foobars", -1},
+ {"foofyfoobarfoobar", "y", 4},
+ {"oooooooooooooooooooooo", "r", -1},
+ {"oxoxoxoxoxoxoxoxoxoxoxoy", "oy", 22},
+ {"oxoxoxoxoxoxoxoxoxoxoxox", "oy", -1},
+ // test fallback to Rabin-Karp.
+ {"000000000000000000000000000000000000000000000000000000000000000000000001", "0000000000000000000000000000000000000000000000000000000000000000001", 5},
+ // test fallback to IndexRune
+ {"oxoxoxoxoxoxoxoxoxoxox☺", "☺", 22},
+ // invalid UTF-8 byte sequence (must be longer than bytealg.MaxBruteForce to
+ // test that we don't use IndexRune)
+ {"xx0123456789012345678901234567890123456789012345678901234567890120123456789012345678901234567890123456xxx\xed\x9f\xc0", "\xed\x9f\xc0", 105},
+}
+
+var lastIndexTests = []BinOpTest{
+ {"", "", 0},
+ {"", "a", -1},
+ {"", "foo", -1},
+ {"fo", "foo", -1},
+ {"foo", "foo", 0},
+ {"foo", "f", 0},
+ {"oofofoofooo", "f", 7},
+ {"oofofoofooo", "foo", 7},
+ {"barfoobarfoo", "foo", 9},
+ {"foo", "", 3},
+ {"foo", "o", 2},
+ {"abcABCabc", "A", 3},
+ {"abcABCabc", "a", 6},
+}
+
+var indexAnyTests = []BinOpTest{
+ {"", "", -1},
+ {"", "a", -1},
+ {"", "abc", -1},
+ {"a", "", -1},
+ {"a", "a", 0},
+ {"\x80", "\xffb", 0},
+ {"aaa", "a", 0},
+ {"abc", "xyz", -1},
+ {"abc", "xcz", 2},
+ {"ab☺c", "x☺yz", 2},
+ {"a☺b☻c☹d", "cx", len("a☺b☻")},
+ {"a☺b☻c☹d", "uvw☻xyz", len("a☺b")},
+ {"aRegExp*", ".(|)*+?^$[]", 7},
+ {dots + dots + dots, " ", -1},
+ {"012abcba210", "\xffb", 4},
+ {"012\x80bcb\x80210", "\xffb", 3},
+ {"0123456\xcf\x80abc", "\xcfb\x80", 10},
+}
+
+var lastIndexAnyTests = []BinOpTest{
+ {"", "", -1},
+ {"", "a", -1},
+ {"", "abc", -1},
+ {"a", "", -1},
+ {"a", "a", 0},
+ {"\x80", "\xffb", 0},
+ {"aaa", "a", 2},
+ {"abc", "xyz", -1},
+ {"abc", "ab", 1},
+ {"ab☺c", "x☺yz", 2},
+ {"a☺b☻c☹d", "cx", len("a☺b☻")},
+ {"a☺b☻c☹d", "uvw☻xyz", len("a☺b")},
+ {"a.RegExp*", ".(|)*+?^$[]", 8},
+ {dots + dots + dots, " ", -1},
+ {"012abcba210", "\xffb", 6},
+ {"012\x80bcb\x80210", "\xffb", 7},
+ {"0123456\xcf\x80abc", "\xcfb\x80", 10},
+}
+
+// Execute f on each test case. funcName should be the name of f; it's used
+// in failure reports.
+func runIndexTests(t *testing.T, f func(s, sep []byte) int, funcName string, testCases []BinOpTest) {
+ for _, test := range testCases {
+ a := []byte(test.a)
+ b := []byte(test.b)
+ actual := f(a, b)
+ if actual != test.i {
+ t.Errorf("%s(%q,%q) = %v; want %v", funcName, a, b, actual, test.i)
+ }
+ }
+ var allocTests = []struct {
+ a []byte
+ b []byte
+ i int
+ }{
+ // case for function Index.
+ {[]byte("000000000000000000000000000000000000000000000000000000000000000000000001"), []byte("0000000000000000000000000000000000000000000000000000000000000000001"), 5},
+ // case for function LastIndex.
+ {[]byte("000000000000000000000000000000000000000000000000000000000000000010000"), []byte("00000000000000000000000000000000000000000000000000000000000001"), 3},
+ }
+ allocs := testing.AllocsPerRun(100, func() {
+ if i := Index(allocTests[1].a, allocTests[1].b); i != allocTests[1].i {
+ t.Errorf("Index([]byte(%q), []byte(%q)) = %v; want %v", allocTests[1].a, allocTests[1].b, i, allocTests[1].i)
+ }
+ if i := LastIndex(allocTests[0].a, allocTests[0].b); i != allocTests[0].i {
+ t.Errorf("LastIndex([]byte(%q), []byte(%q)) = %v; want %v", allocTests[0].a, allocTests[0].b, i, allocTests[0].i)
+ }
+ })
+ if allocs != 0 {
+ t.Errorf("expected no allocations, got %f", allocs)
+ }
+}
+
+func runIndexAnyTests(t *testing.T, f func(s []byte, chars string) int, funcName string, testCases []BinOpTest) {
+ for _, test := range testCases {
+ a := []byte(test.a)
+ actual := f(a, test.b)
+ if actual != test.i {
+ t.Errorf("%s(%q,%q) = %v; want %v", funcName, a, test.b, actual, test.i)
+ }
+ }
+}
+
+func TestIndex(t *testing.T) { runIndexTests(t, Index, "Index", indexTests) }
+func TestLastIndex(t *testing.T) { runIndexTests(t, LastIndex, "LastIndex", lastIndexTests) }
+func TestIndexAny(t *testing.T) { runIndexAnyTests(t, IndexAny, "IndexAny", indexAnyTests) }
+func TestLastIndexAny(t *testing.T) {
+ runIndexAnyTests(t, LastIndexAny, "LastIndexAny", lastIndexAnyTests)
+}
+
+func TestIndexByte(t *testing.T) {
+ for _, tt := range indexTests {
+ if len(tt.b) != 1 {
+ continue
+ }
+ a := []byte(tt.a)
+ b := tt.b[0]
+ pos := IndexByte(a, b)
+ if pos != tt.i {
+ t.Errorf(`IndexByte(%q, '%c') = %v`, tt.a, b, pos)
+ }
+ posp := IndexBytePortable(a, b)
+ if posp != tt.i {
+ t.Errorf(`indexBytePortable(%q, '%c') = %v`, tt.a, b, posp)
+ }
+ }
+}
+
+func TestLastIndexByte(t *testing.T) {
+ testCases := []BinOpTest{
+ {"", "q", -1},
+ {"abcdef", "q", -1},
+ {"abcdefabcdef", "a", len("abcdef")}, // something in the middle
+ {"abcdefabcdef", "f", len("abcdefabcde")}, // last byte
+ {"zabcdefabcdef", "z", 0}, // first byte
+ {"a☺b☻c☹d", "b", len("a☺")}, // non-ascii
+ }
+ for _, test := range testCases {
+ actual := LastIndexByte([]byte(test.a), test.b[0])
+ if actual != test.i {
+ t.Errorf("LastIndexByte(%q,%c) = %v; want %v", test.a, test.b[0], actual, test.i)
+ }
+ }
+}
+
+// test a larger buffer with different sizes and alignments
+func TestIndexByteBig(t *testing.T) {
+ var n = 1024
+ if testing.Short() {
+ n = 128
+ }
+ b := make([]byte, n)
+ for i := 0; i < n; i++ {
+ // different start alignments
+ b1 := b[i:]
+ for j := 0; j < len(b1); j++ {
+ b1[j] = 'x'
+ pos := IndexByte(b1, 'x')
+ if pos != j {
+ t.Errorf("IndexByte(%q, 'x') = %v", b1, pos)
+ }
+ b1[j] = 0
+ pos = IndexByte(b1, 'x')
+ if pos != -1 {
+ t.Errorf("IndexByte(%q, 'x') = %v", b1, pos)
+ }
+ }
+ // different end alignments
+ b1 = b[:i]
+ for j := 0; j < len(b1); j++ {
+ b1[j] = 'x'
+ pos := IndexByte(b1, 'x')
+ if pos != j {
+ t.Errorf("IndexByte(%q, 'x') = %v", b1, pos)
+ }
+ b1[j] = 0
+ pos = IndexByte(b1, 'x')
+ if pos != -1 {
+ t.Errorf("IndexByte(%q, 'x') = %v", b1, pos)
+ }
+ }
+ // different start and end alignments
+ b1 = b[i/2 : n-(i+1)/2]
+ for j := 0; j < len(b1); j++ {
+ b1[j] = 'x'
+ pos := IndexByte(b1, 'x')
+ if pos != j {
+ t.Errorf("IndexByte(%q, 'x') = %v", b1, pos)
+ }
+ b1[j] = 0
+ pos = IndexByte(b1, 'x')
+ if pos != -1 {
+ t.Errorf("IndexByte(%q, 'x') = %v", b1, pos)
+ }
+ }
+ }
+}
+
+// test a small index across all page offsets
+func TestIndexByteSmall(t *testing.T) {
+ b := make([]byte, 5015) // bigger than a page
+ // Make sure we find the correct byte even when straddling a page.
+ for i := 0; i <= len(b)-15; i++ {
+ for j := 0; j < 15; j++ {
+ b[i+j] = byte(100 + j)
+ }
+ for j := 0; j < 15; j++ {
+ p := IndexByte(b[i:i+15], byte(100+j))
+ if p != j {
+ t.Errorf("IndexByte(%q, %d) = %d", b[i:i+15], 100+j, p)
+ }
+ }
+ for j := 0; j < 15; j++ {
+ b[i+j] = 0
+ }
+ }
+ // Make sure matches outside the slice never trigger.
+ for i := 0; i <= len(b)-15; i++ {
+ for j := 0; j < 15; j++ {
+ b[i+j] = 1
+ }
+ for j := 0; j < 15; j++ {
+ p := IndexByte(b[i:i+15], byte(0))
+ if p != -1 {
+ t.Errorf("IndexByte(%q, %d) = %d", b[i:i+15], 0, p)
+ }
+ }
+ for j := 0; j < 15; j++ {
+ b[i+j] = 0
+ }
+ }
+}
+
+func TestIndexRune(t *testing.T) {
+ tests := []struct {
+ in string
+ rune rune
+ want int
+ }{
+ {"", 'a', -1},
+ {"", '☺', -1},
+ {"foo", '☹', -1},
+ {"foo", 'o', 1},
+ {"foo☺bar", '☺', 3},
+ {"foo☺☻☹bar", '☹', 9},
+ {"a A x", 'A', 2},
+ {"some_text=some_value", '=', 9},
+ {"☺a", 'a', 3},
+ {"a☻☺b", '☺', 4},
+ {"𠀳𠀗𠀾𠁄𠀧𠁆𠁂𠀫𠀖𠀪𠀲𠀴𠁀𠀨𠀿", '𠀿', 56},
+
+ // 2 bytes
+ {"ӆ", 'ӆ', 0},
+ {"a", 'ӆ', -1},
+ {" ӆ", 'ӆ', 2},
+ {" a", 'ӆ', -1},
+ {strings.Repeat("ц", 64) + "ӆ", 'ӆ', 128}, // test cutover
+ {strings.Repeat("ц", 64), 'ӆ', -1},
+
+ // 3 bytes
+ {"Ꚁ", 'Ꚁ', 0},
+ {"a", 'Ꚁ', -1},
+ {" Ꚁ", 'Ꚁ', 2},
+ {" a", 'Ꚁ', -1},
+ {strings.Repeat("Ꙁ", 64) + "Ꚁ", 'Ꚁ', 192}, // test cutover
+ {strings.Repeat("Ꙁ", 64) + "Ꚁ", '䚀', -1}, // 'Ꚁ' and '䚀' share the same last two bytes
+
+ // 4 bytes
+ {"𡌀", '𡌀', 0},
+ {"a", '𡌀', -1},
+ {" 𡌀", '𡌀', 2},
+ {" a", '𡌀', -1},
+ {strings.Repeat("𡋀", 64) + "𡌀", '𡌀', 256}, // test cutover
+ {strings.Repeat("𡋀", 64) + "𡌀", '𣌀', -1}, // '𡌀' and '𣌀' share the same last two bytes
+
+ // RuneError should match any invalid UTF-8 byte sequence.
+ {"�", '�', 0},
+ {"\xff", '�', 0},
+ {"☻x�", '�', len("☻x")},
+ {"☻x\xe2\x98", '�', len("☻x")},
+ {"☻x\xe2\x98�", '�', len("☻x")},
+ {"☻x\xe2\x98x", '�', len("☻x")},
+
+ // Invalid rune values should never match.
+ {"a☺b☻c☹d\xe2\x98�\xff�\xed\xa0\x80", -1, -1},
+ {"a☺b☻c☹d\xe2\x98�\xff�\xed\xa0\x80", 0xD800, -1}, // Surrogate pair
+ {"a☺b☻c☹d\xe2\x98�\xff�\xed\xa0\x80", utf8.MaxRune + 1, -1},
+
+ // Test the cutover to bytealg.Index when it is triggered in
+ // the middle of rune that contains consecutive runs of equal bytes.
+ {"aaaaaKKKK\U000bc104", '\U000bc104', 17}, // cutover: (n + 16) / 8
+ {"aaaaaKKKK鄄", '鄄', 17},
+ {"aaKKKKKa\U000bc104", '\U000bc104', 18}, // cutover: 4 + n>>4
+ {"aaKKKKKa鄄", '鄄', 18},
+ }
+ for _, tt := range tests {
+ if got := IndexRune([]byte(tt.in), tt.rune); got != tt.want {
+ t.Errorf("IndexRune(%q, %d) = %v; want %v", tt.in, tt.rune, got, tt.want)
+ }
+ }
+
+ haystack := []byte("test世界")
+ allocs := testing.AllocsPerRun(1000, func() {
+ if i := IndexRune(haystack, 's'); i != 2 {
+ t.Fatalf("'s' at %d; want 2", i)
+ }
+ if i := IndexRune(haystack, '世'); i != 4 {
+ t.Fatalf("'世' at %d; want 4", i)
+ }
+ })
+ if allocs != 0 {
+ t.Errorf("expected no allocations, got %f", allocs)
+ }
+}
+
+// test count of a single byte across page offsets
+func TestCountByte(t *testing.T) {
+ b := make([]byte, 5015) // bigger than a page
+ windows := []int{1, 2, 3, 4, 15, 16, 17, 31, 32, 33, 63, 64, 65, 128}
+ testCountWindow := func(i, window int) {
+ for j := 0; j < window; j++ {
+ b[i+j] = byte(100)
+ p := Count(b[i:i+window], []byte{100})
+ if p != j+1 {
+ t.Errorf("TestCountByte.Count(%q, 100) = %d", b[i:i+window], p)
+ }
+ }
+ }
+
+ maxWnd := windows[len(windows)-1]
+
+ for i := 0; i <= 2*maxWnd; i++ {
+ for _, window := range windows {
+ if window > len(b[i:]) {
+ window = len(b[i:])
+ }
+ testCountWindow(i, window)
+ for j := 0; j < window; j++ {
+ b[i+j] = byte(0)
+ }
+ }
+ }
+ for i := 4096 - (maxWnd + 1); i < len(b); i++ {
+ for _, window := range windows {
+ if window > len(b[i:]) {
+ window = len(b[i:])
+ }
+ testCountWindow(i, window)
+ for j := 0; j < window; j++ {
+ b[i+j] = byte(0)
+ }
+ }
+ }
+}
+
+// Make sure we don't count bytes outside our window
+func TestCountByteNoMatch(t *testing.T) {
+ b := make([]byte, 5015)
+ windows := []int{1, 2, 3, 4, 15, 16, 17, 31, 32, 33, 63, 64, 65, 128}
+ for i := 0; i <= len(b); i++ {
+ for _, window := range windows {
+ if window > len(b[i:]) {
+ window = len(b[i:])
+ }
+ // Fill the window with non-match
+ for j := 0; j < window; j++ {
+ b[i+j] = byte(100)
+ }
+ // Try to find something that doesn't exist
+ p := Count(b[i:i+window], []byte{0})
+ if p != 0 {
+ t.Errorf("TestCountByteNoMatch(%q, 0) = %d", b[i:i+window], p)
+ }
+ for j := 0; j < window; j++ {
+ b[i+j] = byte(0)
+ }
+ }
+ }
+}
+
+var bmbuf []byte
+
+func valName(x int) string {
+ if s := x >> 20; s<<20 == x {
+ return fmt.Sprintf("%dM", s)
+ }
+ if s := x >> 10; s<<10 == x {
+ return fmt.Sprintf("%dK", s)
+ }
+ return fmt.Sprint(x)
+}
+
+func benchBytes(b *testing.B, sizes []int, f func(b *testing.B, n int)) {
+ for _, n := range sizes {
+ if isRaceBuilder && n > 4<<10 {
+ continue
+ }
+ b.Run(valName(n), func(b *testing.B) {
+ if len(bmbuf) < n {
+ bmbuf = make([]byte, n)
+ }
+ b.SetBytes(int64(n))
+ f(b, n)
+ })
+ }
+}
+
+var indexSizes = []int{10, 32, 4 << 10, 4 << 20, 64 << 20}
+
+var isRaceBuilder = strings.HasSuffix(testenv.Builder(), "-race")
+
+func BenchmarkIndexByte(b *testing.B) {
+ benchBytes(b, indexSizes, bmIndexByte(IndexByte))
+}
+
+func BenchmarkIndexBytePortable(b *testing.B) {
+ benchBytes(b, indexSizes, bmIndexByte(IndexBytePortable))
+}
+
+func bmIndexByte(index func([]byte, byte) int) func(b *testing.B, n int) {
+ return func(b *testing.B, n int) {
+ buf := bmbuf[0:n]
+ buf[n-1] = 'x'
+ for i := 0; i < b.N; i++ {
+ j := index(buf, 'x')
+ if j != n-1 {
+ b.Fatal("bad index", j)
+ }
+ }
+ buf[n-1] = '\x00'
+ }
+}
+
+func BenchmarkIndexRune(b *testing.B) {
+ benchBytes(b, indexSizes, bmIndexRune(IndexRune))
+}
+
+func BenchmarkIndexRuneASCII(b *testing.B) {
+ benchBytes(b, indexSizes, bmIndexRuneASCII(IndexRune))
+}
+
+func BenchmarkIndexRuneUnicode(b *testing.B) {
+ b.Run("Latin", func(b *testing.B) {
+ // Latin is mostly 1, 2, 3 byte runes.
+ benchBytes(b, indexSizes, bmIndexRuneUnicode(unicode.Latin, 'é'))
+ })
+ b.Run("Cyrillic", func(b *testing.B) {
+ // Cyrillic is mostly 2 and 3 byte runes.
+ benchBytes(b, indexSizes, bmIndexRuneUnicode(unicode.Cyrillic, 'Ꙁ'))
+ })
+ b.Run("Han", func(b *testing.B) {
+ // Han consists only of 3 and 4 byte runes.
+ benchBytes(b, indexSizes, bmIndexRuneUnicode(unicode.Han, '𠀿'))
+ })
+}
+
+func bmIndexRuneASCII(index func([]byte, rune) int) func(b *testing.B, n int) {
+ return func(b *testing.B, n int) {
+ buf := bmbuf[0:n]
+ buf[n-1] = 'x'
+ for i := 0; i < b.N; i++ {
+ j := index(buf, 'x')
+ if j != n-1 {
+ b.Fatal("bad index", j)
+ }
+ }
+ buf[n-1] = '\x00'
+ }
+}
+
+func bmIndexRune(index func([]byte, rune) int) func(b *testing.B, n int) {
+ return func(b *testing.B, n int) {
+ buf := bmbuf[0:n]
+ utf8.EncodeRune(buf[n-3:], '世')
+ for i := 0; i < b.N; i++ {
+ j := index(buf, '世')
+ if j != n-3 {
+ b.Fatal("bad index", j)
+ }
+ }
+ buf[n-3] = '\x00'
+ buf[n-2] = '\x00'
+ buf[n-1] = '\x00'
+ }
+}
+
+func bmIndexRuneUnicode(rt *unicode.RangeTable, needle rune) func(b *testing.B, n int) {
+ var rs []rune
+ for _, r16 := range rt.R16 {
+ for r := rune(r16.Lo); r <= rune(r16.Hi); r += rune(r16.Stride) {
+ if r != needle {
+ rs = append(rs, r)
+ }
+ }
+ }
+ for _, r32 := range rt.R32 {
+ for r := rune(r32.Lo); r <= rune(r32.Hi); r += rune(r32.Stride) {
+ if r != needle {
+ rs = append(rs, r)
+ }
+ }
+ }
+ // Shuffle the runes so that they are not in descending order.
+ // The sort is deterministic since this is used for benchmarks,
+ // which need to be repeatable.
+ rr := rand.New(rand.NewSource(1))
+ rr.Shuffle(len(rs), func(i, j int) {
+ rs[i], rs[j] = rs[j], rs[i]
+ })
+ uchars := string(rs)
+
+ return func(b *testing.B, n int) {
+ buf := bmbuf[0:n]
+ o := copy(buf, uchars)
+ for o < len(buf) {
+ o += copy(buf[o:], uchars)
+ }
+
+ // Make space for the needle rune at the end of buf.
+ m := utf8.RuneLen(needle)
+ for o := m; o > 0; {
+ _, sz := utf8.DecodeLastRune(buf)
+ copy(buf[len(buf)-sz:], "\x00\x00\x00\x00")
+ buf = buf[:len(buf)-sz]
+ o -= sz
+ }
+ buf = utf8.AppendRune(buf[:n-m], needle)
+
+ n -= m // adjust for rune len
+ for i := 0; i < b.N; i++ {
+ j := IndexRune(buf, needle)
+ if j != n {
+ b.Fatal("bad index", j)
+ }
+ }
+ for i := range buf {
+ buf[i] = '\x00'
+ }
+ }
+}
+
+func BenchmarkEqual(b *testing.B) {
+ b.Run("0", func(b *testing.B) {
+ var buf [4]byte
+ buf1 := buf[0:0]
+ buf2 := buf[1:1]
+ for i := 0; i < b.N; i++ {
+ eq := Equal(buf1, buf2)
+ if !eq {
+ b.Fatal("bad equal")
+ }
+ }
+ })
+
+ sizes := []int{1, 6, 9, 15, 16, 20, 32, 4 << 10, 4 << 20, 64 << 20}
+
+ b.Run("same", func(b *testing.B) {
+ benchBytes(b, sizes, bmEqual(func(a, b []byte) bool { return Equal(a, a) }))
+ })
+
+ benchBytes(b, sizes, bmEqual(Equal))
+}
+
+func bmEqual(equal func([]byte, []byte) bool) func(b *testing.B, n int) {
+ return func(b *testing.B, n int) {
+ if len(bmbuf) < 2*n {
+ bmbuf = make([]byte, 2*n)
+ }
+ buf1 := bmbuf[0:n]
+ buf2 := bmbuf[n : 2*n]
+ buf1[n-1] = 'x'
+ buf2[n-1] = 'x'
+ for i := 0; i < b.N; i++ {
+ eq := equal(buf1, buf2)
+ if !eq {
+ b.Fatal("bad equal")
+ }
+ }
+ buf1[n-1] = '\x00'
+ buf2[n-1] = '\x00'
+ }
+}
+
+func BenchmarkEqualBothUnaligned(b *testing.B) {
+ sizes := []int{64, 4 << 10}
+ if !isRaceBuilder {
+ sizes = append(sizes, []int{4 << 20, 64 << 20}...)
+ }
+ maxSize := 2 * (sizes[len(sizes)-1] + 8)
+ if len(bmbuf) < maxSize {
+ bmbuf = make([]byte, maxSize)
+ }
+
+ for _, n := range sizes {
+ for _, off := range []int{0, 1, 4, 7} {
+ buf1 := bmbuf[off : off+n]
+ buf2Start := (len(bmbuf) / 2) + off
+ buf2 := bmbuf[buf2Start : buf2Start+n]
+ buf1[n-1] = 'x'
+ buf2[n-1] = 'x'
+ b.Run(fmt.Sprint(n, off), func(b *testing.B) {
+ b.SetBytes(int64(n))
+ for i := 0; i < b.N; i++ {
+ eq := Equal(buf1, buf2)
+ if !eq {
+ b.Fatal("bad equal")
+ }
+ }
+ })
+ buf1[n-1] = '\x00'
+ buf2[n-1] = '\x00'
+ }
+ }
+}
+
+func BenchmarkIndex(b *testing.B) {
+ benchBytes(b, indexSizes, func(b *testing.B, n int) {
+ buf := bmbuf[0:n]
+ buf[n-1] = 'x'
+ for i := 0; i < b.N; i++ {
+ j := Index(buf, buf[n-7:])
+ if j != n-7 {
+ b.Fatal("bad index", j)
+ }
+ }
+ buf[n-1] = '\x00'
+ })
+}
+
+func BenchmarkIndexEasy(b *testing.B) {
+ benchBytes(b, indexSizes, func(b *testing.B, n int) {
+ buf := bmbuf[0:n]
+ buf[n-1] = 'x'
+ buf[n-7] = 'x'
+ for i := 0; i < b.N; i++ {
+ j := Index(buf, buf[n-7:])
+ if j != n-7 {
+ b.Fatal("bad index", j)
+ }
+ }
+ buf[n-1] = '\x00'
+ buf[n-7] = '\x00'
+ })
+}
+
+func BenchmarkCount(b *testing.B) {
+ benchBytes(b, indexSizes, func(b *testing.B, n int) {
+ buf := bmbuf[0:n]
+ buf[n-1] = 'x'
+ for i := 0; i < b.N; i++ {
+ j := Count(buf, buf[n-7:])
+ if j != 1 {
+ b.Fatal("bad count", j)
+ }
+ }
+ buf[n-1] = '\x00'
+ })
+}
+
+func BenchmarkCountEasy(b *testing.B) {
+ benchBytes(b, indexSizes, func(b *testing.B, n int) {
+ buf := bmbuf[0:n]
+ buf[n-1] = 'x'
+ buf[n-7] = 'x'
+ for i := 0; i < b.N; i++ {
+ j := Count(buf, buf[n-7:])
+ if j != 1 {
+ b.Fatal("bad count", j)
+ }
+ }
+ buf[n-1] = '\x00'
+ buf[n-7] = '\x00'
+ })
+}
+
+func BenchmarkCountSingle(b *testing.B) {
+ benchBytes(b, indexSizes, func(b *testing.B, n int) {
+ buf := bmbuf[0:n]
+ step := 8
+ for i := 0; i < len(buf); i += step {
+ buf[i] = 1
+ }
+ expect := (len(buf) + (step - 1)) / step
+ for i := 0; i < b.N; i++ {
+ j := Count(buf, []byte{1})
+ if j != expect {
+ b.Fatal("bad count", j, expect)
+ }
+ }
+ clear(buf)
+ })
+}
+
+type SplitTest struct {
+ s string
+ sep string
+ n int
+ a []string
+}
+
+var splittests = []SplitTest{
+ {"", "", -1, []string{}},
+ {abcd, "a", 0, nil},
+ {abcd, "", 2, []string{"a", "bcd"}},
+ {abcd, "a", -1, []string{"", "bcd"}},
+ {abcd, "z", -1, []string{"abcd"}},
+ {abcd, "", -1, []string{"a", "b", "c", "d"}},
+ {commas, ",", -1, []string{"1", "2", "3", "4"}},
+ {dots, "...", -1, []string{"1", ".2", ".3", ".4"}},
+ {faces, "☹", -1, []string{"☺☻", ""}},
+ {faces, "~", -1, []string{faces}},
+ {faces, "", -1, []string{"☺", "☻", "☹"}},
+ {"1 2 3 4", " ", 3, []string{"1", "2", "3 4"}},
+ {"1 2", " ", 3, []string{"1", "2"}},
+ {"123", "", 2, []string{"1", "23"}},
+ {"123", "", 17, []string{"1", "2", "3"}},
+ {"bT", "T", math.MaxInt / 4, []string{"b", ""}},
+ {"\xff-\xff", "", -1, []string{"\xff", "-", "\xff"}},
+ {"\xff-\xff", "-", -1, []string{"\xff", "\xff"}},
+}
+
+func TestSplit(t *testing.T) {
+ for _, tt := range splittests {
+ a := SplitN([]byte(tt.s), []byte(tt.sep), tt.n)
+
+ // Appending to the results should not change future results.
+ var x []byte
+ for _, v := range a {
+ x = append(v, 'z')
+ }
+
+ result := sliceOfString(a)
+ if !slices.Equal(result, tt.a) {
+ t.Errorf(`Split(%q, %q, %d) = %v; want %v`, tt.s, tt.sep, tt.n, result, tt.a)
+ continue
+ }
+
+ if tt.n < 0 {
+ b := sliceOfString(slices.Collect(SplitSeq([]byte(tt.s), []byte(tt.sep))))
+ if !slices.Equal(b, tt.a) {
+ t.Errorf(`collect(SplitSeq(%q, %q)) = %v; want %v`, tt.s, tt.sep, b, tt.a)
+ }
+ }
+
+ if tt.n == 0 || len(a) == 0 {
+ continue
+ }
+
+ if want := tt.a[len(tt.a)-1] + "z"; string(x) != want {
+ t.Errorf("last appended result was %s; want %s", x, want)
+ }
+
+ s := Join(a, []byte(tt.sep))
+ if string(s) != tt.s {
+ t.Errorf(`Join(Split(%q, %q, %d), %q) = %q`, tt.s, tt.sep, tt.n, tt.sep, s)
+ }
+ if tt.n < 0 {
+ b := sliceOfString(Split([]byte(tt.s), []byte(tt.sep)))
+ if !slices.Equal(result, b) {
+ t.Errorf("Split disagrees with SplitN(%q, %q, %d) = %v; want %v", tt.s, tt.sep, tt.n, b, a)
+ }
+ }
+ if len(a) > 0 {
+ in, out := a[0], s
+ if cap(in) == cap(out) && &in[:1][0] == &out[:1][0] {
+ t.Errorf("Join(%#v, %q) didn't copy", a, tt.sep)
+ }
+ }
+ }
+}
+
+var splitaftertests = []SplitTest{
+ {abcd, "a", -1, []string{"a", "bcd"}},
+ {abcd, "z", -1, []string{"abcd"}},
+ {abcd, "", -1, []string{"a", "b", "c", "d"}},
+ {commas, ",", -1, []string{"1,", "2,", "3,", "4"}},
+ {dots, "...", -1, []string{"1...", ".2...", ".3...", ".4"}},
+ {faces, "☹", -1, []string{"☺☻☹", ""}},
+ {faces, "~", -1, []string{faces}},
+ {faces, "", -1, []string{"☺", "☻", "☹"}},
+ {"1 2 3 4", " ", 3, []string{"1 ", "2 ", "3 4"}},
+ {"1 2 3", " ", 3, []string{"1 ", "2 ", "3"}},
+ {"1 2", " ", 3, []string{"1 ", "2"}},
+ {"123", "", 2, []string{"1", "23"}},
+ {"123", "", 17, []string{"1", "2", "3"}},
+}
+
+func TestSplitAfter(t *testing.T) {
+ for _, tt := range splitaftertests {
+ a := SplitAfterN([]byte(tt.s), []byte(tt.sep), tt.n)
+
+ // Appending to the results should not change future results.
+ var x []byte
+ for _, v := range a {
+ x = append(v, 'z')
+ }
+
+ result := sliceOfString(a)
+ if !slices.Equal(result, tt.a) {
+ t.Errorf(`Split(%q, %q, %d) = %v; want %v`, tt.s, tt.sep, tt.n, result, tt.a)
+ continue
+ }
+
+ if tt.n < 0 {
+ b := sliceOfString(slices.Collect(SplitAfterSeq([]byte(tt.s), []byte(tt.sep))))
+ if !slices.Equal(b, tt.a) {
+ t.Errorf(`collect(SplitAfterSeq(%q, %q)) = %v; want %v`, tt.s, tt.sep, b, tt.a)
+ }
+ }
+
+ if want := tt.a[len(tt.a)-1] + "z"; string(x) != want {
+ t.Errorf("last appended result was %s; want %s", x, want)
+ }
+
+ s := Join(a, nil)
+ if string(s) != tt.s {
+ t.Errorf(`Join(Split(%q, %q, %d), %q) = %q`, tt.s, tt.sep, tt.n, tt.sep, s)
+ }
+ if tt.n < 0 {
+ b := sliceOfString(SplitAfter([]byte(tt.s), []byte(tt.sep)))
+ if !slices.Equal(result, b) {
+ t.Errorf("SplitAfter disagrees with SplitAfterN(%q, %q, %d) = %v; want %v", tt.s, tt.sep, tt.n, b, a)
+ }
+ }
+ }
+}
+
+type FieldsTest struct {
+ s string
+ a []string
+}
+
+var fieldstests = []FieldsTest{
+ {"", []string{}},
+ {" ", []string{}},
+ {" \t ", []string{}},
+ {" abc ", []string{"abc"}},
+ {"1 2 3 4", []string{"1", "2", "3", "4"}},
+ {"1 2 3 4", []string{"1", "2", "3", "4"}},
+ {"1\t\t2\t\t3\t4", []string{"1", "2", "3", "4"}},
+ {"1\u20002\u20013\u20024", []string{"1", "2", "3", "4"}},
+ {"\u2000\u2001\u2002", []string{}},
+ {"\n™\t™\n", []string{"™", "™"}},
+ {faces, []string{faces}},
+}
+
+func TestFields(t *testing.T) {
+ for _, tt := range fieldstests {
+ b := []byte(tt.s)
+ a := Fields(b)
+
+ // Appending to the results should not change future results.
+ var x []byte
+ for _, v := range a {
+ x = append(v, 'z')
+ }
+
+ result := sliceOfString(a)
+ if !slices.Equal(result, tt.a) {
+ t.Errorf("Fields(%q) = %v; want %v", tt.s, a, tt.a)
+ continue
+ }
+
+ result2 := sliceOfString(collect(t, FieldsSeq([]byte(tt.s))))
+ if !slices.Equal(result2, tt.a) {
+ t.Errorf(`collect(FieldsSeq(%q)) = %v; want %v`, tt.s, result2, tt.a)
+ }
+
+ if string(b) != tt.s {
+ t.Errorf("slice changed to %s; want %s", string(b), tt.s)
+ }
+ if len(tt.a) > 0 {
+ if want := tt.a[len(tt.a)-1] + "z"; string(x) != want {
+ t.Errorf("last appended result was %s; want %s", x, want)
+ }
+ }
+ }
+}
+
+func TestFieldsFunc(t *testing.T) {
+ for _, tt := range fieldstests {
+ a := FieldsFunc([]byte(tt.s), unicode.IsSpace)
+ result := sliceOfString(a)
+ if !slices.Equal(result, tt.a) {
+ t.Errorf("FieldsFunc(%q, unicode.IsSpace) = %v; want %v", tt.s, a, tt.a)
+ continue
+ }
+ }
+ pred := func(c rune) bool { return c == 'X' }
+ var fieldsFuncTests = []FieldsTest{
+ {"", []string{}},
+ {"XX", []string{}},
+ {"XXhiXXX", []string{"hi"}},
+ {"aXXbXXXcX", []string{"a", "b", "c"}},
+ }
+ for _, tt := range fieldsFuncTests {
+ b := []byte(tt.s)
+ a := FieldsFunc(b, pred)
+
+ // Appending to the results should not change future results.
+ var x []byte
+ for _, v := range a {
+ x = append(v, 'z')
+ }
+
+ result := sliceOfString(a)
+ if !slices.Equal(result, tt.a) {
+ t.Errorf("FieldsFunc(%q) = %v, want %v", tt.s, a, tt.a)
+ }
+
+ result2 := sliceOfString(collect(t, FieldsFuncSeq([]byte(tt.s), pred)))
+ if !slices.Equal(result2, tt.a) {
+ t.Errorf(`collect(FieldsFuncSeq(%q)) = %v; want %v`, tt.s, result2, tt.a)
+ }
+
+ if string(b) != tt.s {
+ t.Errorf("slice changed to %s; want %s", b, tt.s)
+ }
+ if len(tt.a) > 0 {
+ if want := tt.a[len(tt.a)-1] + "z"; string(x) != want {
+ t.Errorf("last appended result was %s; want %s", x, want)
+ }
+ }
+ }
+}
+
+// Test case for any function which accepts and returns a byte slice.
+// For ease of creation, we write the input byte slice as a string.
+type StringTest struct {
+ in string
+ out []byte
+}
+
+var upperTests = []StringTest{
+ {"", []byte("")},
+ {"ONLYUPPER", []byte("ONLYUPPER")},
+ {"abc", []byte("ABC")},
+ {"AbC123", []byte("ABC123")},
+ {"azAZ09_", []byte("AZAZ09_")},
+ {"longStrinGwitHmixofsmaLLandcAps", []byte("LONGSTRINGWITHMIXOFSMALLANDCAPS")},
+ {"long\u0250string\u0250with\u0250nonascii\u2C6Fchars", []byte("LONG\u2C6FSTRING\u2C6FWITH\u2C6FNONASCII\u2C6FCHARS")},
+ {"\u0250\u0250\u0250\u0250\u0250", []byte("\u2C6F\u2C6F\u2C6F\u2C6F\u2C6F")}, // grows one byte per char
+ {"a\u0080\U0010FFFF", []byte("A\u0080\U0010FFFF")}, // test utf8.RuneSelf and utf8.MaxRune
+}
+
+var lowerTests = []StringTest{
+ {"", []byte("")},
+ {"abc", []byte("abc")},
+ {"AbC123", []byte("abc123")},
+ {"azAZ09_", []byte("azaz09_")},
+ {"longStrinGwitHmixofsmaLLandcAps", []byte("longstringwithmixofsmallandcaps")},
+ {"LONG\u2C6FSTRING\u2C6FWITH\u2C6FNONASCII\u2C6FCHARS", []byte("long\u0250string\u0250with\u0250nonascii\u0250chars")},
+ {"\u2C6D\u2C6D\u2C6D\u2C6D\u2C6D", []byte("\u0251\u0251\u0251\u0251\u0251")}, // shrinks one byte per char
+ {"A\u0080\U0010FFFF", []byte("a\u0080\U0010FFFF")}, // test utf8.RuneSelf and utf8.MaxRune
+}
+
+const space = "\t\v\r\f\n\u0085\u00a0\u2000\u3000"
+
+var trimSpaceTests = []StringTest{
+ {"", nil},
+ {" a", []byte("a")},
+ {"b ", []byte("b")},
+ {"abc", []byte("abc")},
+ {space + "abc" + space, []byte("abc")},
+ {" ", nil},
+ {"\u3000 ", nil},
+ {" \u3000", nil},
+ {" \t\r\n \t\t\r\r\n\n ", nil},
+ {" \t\r\n x\t\t\r\r\n\n ", []byte("x")},
+ {" \u2000\t\r\n x\t\t\r\r\ny\n \u3000", []byte("x\t\t\r\r\ny")},
+ {"1 \t\r\n2", []byte("1 \t\r\n2")},
+ {" x\x80", []byte("x\x80")},
+ {" x\xc0", []byte("x\xc0")},
+ {"x \xc0\xc0 ", []byte("x \xc0\xc0")},
+ {"x \xc0", []byte("x \xc0")},
+ {"x \xc0 ", []byte("x \xc0")},
+ {"x \xc0\xc0 ", []byte("x \xc0\xc0")},
+ {"x ☺\xc0\xc0 ", []byte("x ☺\xc0\xc0")},
+ {"x ☺ ", []byte("x ☺")},
+}
+
+// Execute f on each test case. funcName should be the name of f; it's used
+// in failure reports.
+func runStringTests(t *testing.T, f func([]byte) []byte, funcName string, testCases []StringTest) {
+ for _, tc := range testCases {
+ actual := f([]byte(tc.in))
+ if actual == nil && tc.out != nil {
+ t.Errorf("%s(%q) = nil; want %q", funcName, tc.in, tc.out)
+ }
+ if actual != nil && tc.out == nil {
+ t.Errorf("%s(%q) = %q; want nil", funcName, tc.in, actual)
+ }
+ if !Equal(actual, tc.out) {
+ t.Errorf("%s(%q) = %q; want %q", funcName, tc.in, actual, tc.out)
+ }
+ }
+}
+
+func tenRunes(r rune) string {
+ runes := make([]rune, 10)
+ for i := range runes {
+ runes[i] = r
+ }
+ return string(runes)
+}
+
+// User-defined self-inverse mapping function
+func rot13(r rune) rune {
+ const step = 13
+ if r >= 'a' && r <= 'z' {
+ return ((r - 'a' + step) % 26) + 'a'
+ }
+ if r >= 'A' && r <= 'Z' {
+ return ((r - 'A' + step) % 26) + 'A'
+ }
+ return r
+}
+
+func TestMap(t *testing.T) {
+ // Run a couple of awful growth/shrinkage tests
+ a := tenRunes('a')
+
+ // 1. Grow. This triggers two reallocations in Map.
+ maxRune := func(r rune) rune { return unicode.MaxRune }
+ m := Map(maxRune, []byte(a))
+ expect := tenRunes(unicode.MaxRune)
+ if string(m) != expect {
+ t.Errorf("growing: expected %q got %q", expect, m)
+ }
+
+ // 2. Shrink
+ minRune := func(r rune) rune { return 'a' }
+ m = Map(minRune, []byte(tenRunes(unicode.MaxRune)))
+ expect = a
+ if string(m) != expect {
+ t.Errorf("shrinking: expected %q got %q", expect, m)
+ }
+
+ // 3. Rot13
+ m = Map(rot13, []byte("a to zed"))
+ expect = "n gb mrq"
+ if string(m) != expect {
+ t.Errorf("rot13: expected %q got %q", expect, m)
+ }
+
+ // 4. Rot13^2
+ m = Map(rot13, Map(rot13, []byte("a to zed")))
+ expect = "a to zed"
+ if string(m) != expect {
+ t.Errorf("rot13: expected %q got %q", expect, m)
+ }
+
+ // 5. Drop
+ dropNotLatin := func(r rune) rune {
+ if unicode.Is(unicode.Latin, r) {
+ return r
+ }
+ return -1
+ }
+ m = Map(dropNotLatin, []byte("Hello, 세계"))
+ expect = "Hello"
+ if string(m) != expect {
+ t.Errorf("drop: expected %q got %q", expect, m)
+ }
+
+ // 6. Invalid rune
+ invalidRune := func(r rune) rune {
+ return utf8.MaxRune + 1
+ }
+ m = Map(invalidRune, []byte("x"))
+ expect = "\uFFFD"
+ if string(m) != expect {
+ t.Errorf("invalidRune: expected %q got %q", expect, m)
+ }
+}
+
+func TestToUpper(t *testing.T) { runStringTests(t, ToUpper, "ToUpper", upperTests) }
+
+func TestToLower(t *testing.T) { runStringTests(t, ToLower, "ToLower", lowerTests) }
+
+func BenchmarkToUpper(b *testing.B) {
+ for _, tc := range upperTests {
+ tin := []byte(tc.in)
+ b.Run(tc.in, func(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ actual := ToUpper(tin)
+ if !Equal(actual, tc.out) {
+ b.Errorf("ToUpper(%q) = %q; want %q", tc.in, actual, tc.out)
+ }
+ }
+ })
+ }
+}
+
+func BenchmarkToLower(b *testing.B) {
+ for _, tc := range lowerTests {
+ tin := []byte(tc.in)
+ b.Run(tc.in, func(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ actual := ToLower(tin)
+ if !Equal(actual, tc.out) {
+ b.Errorf("ToLower(%q) = %q; want %q", tc.in, actual, tc.out)
+ }
+ }
+ })
+ }
+}
+
+var toValidUTF8Tests = []struct {
+ in string
+ repl string
+ out string
+}{
+ {"", "\uFFFD", ""},
+ {"abc", "\uFFFD", "abc"},
+ {"\uFDDD", "\uFFFD", "\uFDDD"},
+ {"a\xffb", "\uFFFD", "a\uFFFDb"},
+ {"a\xffb\uFFFD", "X", "aXb\uFFFD"},
+ {"a☺\xffb☺\xC0\xAFc☺\xff", "", "a☺b☺c☺"},
+ {"a☺\xffb☺\xC0\xAFc☺\xff", "日本語", "a☺日本語b☺日本語c☺日本語"},
+ {"\xC0\xAF", "\uFFFD", "\uFFFD"},
+ {"\xE0\x80\xAF", "\uFFFD", "\uFFFD"},
+ {"\xed\xa0\x80", "abc", "abc"},
+ {"\xed\xbf\xbf", "\uFFFD", "\uFFFD"},
+ {"\xF0\x80\x80\xaf", "☺", "☺"},
+ {"\xF8\x80\x80\x80\xAF", "\uFFFD", "\uFFFD"},
+ {"\xFC\x80\x80\x80\x80\xAF", "\uFFFD", "\uFFFD"},
+}
+
+func TestToValidUTF8(t *testing.T) {
+ for _, tc := range toValidUTF8Tests {
+ got := ToValidUTF8([]byte(tc.in), []byte(tc.repl))
+ if !Equal(got, []byte(tc.out)) {
+ t.Errorf("ToValidUTF8(%q, %q) = %q; want %q", tc.in, tc.repl, got, tc.out)
+ }
+ }
+}
+
+func TestTrimSpace(t *testing.T) { runStringTests(t, TrimSpace, "TrimSpace", trimSpaceTests) }
+
+type RepeatTest struct {
+ in, out string
+ count int
+}
+
+var longString = "a" + string(make([]byte, 1<<16)) + "z"
+
+var RepeatTests = []RepeatTest{
+ {"", "", 0},
+ {"", "", 1},
+ {"", "", 2},
+ {"-", "", 0},
+ {"-", "-", 1},
+ {"-", "----------", 10},
+ {"abc ", "abc abc abc ", 3},
+ // Tests for results over the chunkLimit
+ {string(rune(0)), string(make([]byte, 1<<16)), 1 << 16},
+ {longString, longString + longString, 2},
+}
+
+func TestRepeat(t *testing.T) {
+ for _, tt := range RepeatTests {
+ tin := []byte(tt.in)
+ tout := []byte(tt.out)
+ a := Repeat(tin, tt.count)
+ if !Equal(a, tout) {
+ t.Errorf("Repeat(%q, %d) = %q; want %q", tin, tt.count, a, tout)
+ continue
+ }
+ }
+}
+
+func repeat(b []byte, count int) (err error) {
+ defer func() {
+ if r := recover(); r != nil {
+ switch v := r.(type) {
+ case error:
+ err = v
+ default:
+ err = fmt.Errorf("%s", v)
+ }
+ }
+ }()
+
+ Repeat(b, count)
+
+ return
+}
+
+// See Issue golang.org/issue/16237
+func TestRepeatCatchesOverflow(t *testing.T) {
+ type testCase struct {
+ s string
+ count int
+ errStr string
+ }
+
+ runTestCases := func(prefix string, tests []testCase) {
+ for i, tt := range tests {
+ err := repeat([]byte(tt.s), tt.count)
+ if tt.errStr == "" {
+ if err != nil {
+ t.Errorf("#%d panicked %v", i, err)
+ }
+ continue
+ }
+
+ if err == nil || !strings.Contains(err.Error(), tt.errStr) {
+ t.Errorf("%s#%d got %q want %q", prefix, i, err, tt.errStr)
+ }
+ }
+ }
+
+ const maxInt = int(^uint(0) >> 1)
+
+ runTestCases("", []testCase{
+ 0: {"--", -2147483647, "negative"},
+ 1: {"", maxInt, ""},
+ 2: {"-", 10, ""},
+ 3: {"gopher", 0, ""},
+ 4: {"-", -1, "negative"},
+ 5: {"--", -102, "negative"},
+ 6: {string(make([]byte, 255)), int((^uint(0))/255 + 1), "overflow"},
+ })
+
+ const is64Bit = 1<<(^uintptr(0)>>63)/2 != 0
+ if !is64Bit {
+ return
+ }
+
+ runTestCases("64-bit", []testCase{
+ 0: {"-", maxInt, "out of range"},
+ })
+}
+
+type RunesTest struct {
+ in string
+ out []rune
+ lossy bool
+}
+
+var RunesTests = []RunesTest{
+ {"", []rune{}, false},
+ {" ", []rune{32}, false},
+ {"ABC", []rune{65, 66, 67}, false},
+ {"abc", []rune{97, 98, 99}, false},
+ {"\u65e5\u672c\u8a9e", []rune{26085, 26412, 35486}, false},
+ {"ab\x80c", []rune{97, 98, 0xFFFD, 99}, true},
+ {"ab\xc0c", []rune{97, 98, 0xFFFD, 99}, true},
+}
+
+func TestRunes(t *testing.T) {
+ for _, tt := range RunesTests {
+ tin := []byte(tt.in)
+ a := Runes(tin)
+ if !slices.Equal(a, tt.out) {
+ t.Errorf("Runes(%q) = %v; want %v", tin, a, tt.out)
+ continue
+ }
+ if !tt.lossy {
+ // can only test reassembly if we didn't lose information
+ s := string(a)
+ if s != tt.in {
+ t.Errorf("string(Runes(%q)) = %x; want %x", tin, s, tin)
+ }
+ }
+ }
+}
+
+type TrimTest struct {
+ f string
+ in, arg, out string
+}
+
+var trimTests = []TrimTest{
+ {"Trim", "abba", "a", "bb"},
+ {"Trim", "abba", "ab", ""},
+ {"TrimLeft", "abba", "ab", ""},
+ {"TrimRight", "abba", "ab", ""},
+ {"TrimLeft", "abba", "a", "bba"},
+ {"TrimLeft", "abba", "b", "abba"},
+ {"TrimRight", "abba", "a", "abb"},
+ {"TrimRight", "abba", "b", "abba"},
+ {"Trim", "", "<>", "tag"},
+ {"Trim", "* listitem", " *", "listitem"},
+ {"Trim", `"quote"`, `"`, "quote"},
+ {"Trim", "\u2C6F\u2C6F\u0250\u0250\u2C6F\u2C6F", "\u2C6F", "\u0250\u0250"},
+ {"Trim", "\x80test\xff", "\xff", "test"},
+ {"Trim", " Ġ ", " ", "Ġ"},
+ {"Trim", " Ġİ0", "0 ", "Ġİ"},
+ //empty string tests
+ {"Trim", "abba", "", "abba"},
+ {"Trim", "", "123", ""},
+ {"Trim", "", "", ""},
+ {"TrimLeft", "abba", "", "abba"},
+ {"TrimLeft", "", "123", ""},
+ {"TrimLeft", "", "", ""},
+ {"TrimRight", "abba", "", "abba"},
+ {"TrimRight", "", "123", ""},
+ {"TrimRight", "", "", ""},
+ {"TrimRight", "☺\xc0", "☺", "☺\xc0"},
+ {"TrimPrefix", "aabb", "a", "abb"},
+ {"TrimPrefix", "aabb", "b", "aabb"},
+ {"TrimSuffix", "aabb", "a", "aabb"},
+ {"TrimSuffix", "aabb", "b", "aab"},
+}
+
+type TrimNilTest struct {
+ f string
+ in []byte
+ arg string
+ out []byte
+}
+
+var trimNilTests = []TrimNilTest{
+ {"Trim", nil, "", nil},
+ {"Trim", []byte{}, "", nil},
+ {"Trim", []byte{'a'}, "a", nil},
+ {"Trim", []byte{'a', 'a'}, "a", nil},
+ {"Trim", []byte{'a'}, "ab", nil},
+ {"Trim", []byte{'a', 'b'}, "ab", nil},
+ {"Trim", []byte("☺"), "☺", nil},
+ {"TrimLeft", nil, "", nil},
+ {"TrimLeft", []byte{}, "", nil},
+ {"TrimLeft", []byte{'a'}, "a", nil},
+ {"TrimLeft", []byte{'a', 'a'}, "a", nil},
+ {"TrimLeft", []byte{'a'}, "ab", nil},
+ {"TrimLeft", []byte{'a', 'b'}, "ab", nil},
+ {"TrimLeft", []byte("☺"), "☺", nil},
+ {"TrimRight", nil, "", nil},
+ {"TrimRight", []byte{}, "", []byte{}},
+ {"TrimRight", []byte{'a'}, "a", []byte{}},
+ {"TrimRight", []byte{'a', 'a'}, "a", []byte{}},
+ {"TrimRight", []byte{'a'}, "ab", []byte{}},
+ {"TrimRight", []byte{'a', 'b'}, "ab", []byte{}},
+ {"TrimRight", []byte("☺"), "☺", []byte{}},
+ {"TrimPrefix", nil, "", nil},
+ {"TrimPrefix", []byte{}, "", []byte{}},
+ {"TrimPrefix", []byte{'a'}, "a", []byte{}},
+ {"TrimPrefix", []byte("☺"), "☺", []byte{}},
+ {"TrimSuffix", nil, "", nil},
+ {"TrimSuffix", []byte{}, "", []byte{}},
+ {"TrimSuffix", []byte{'a'}, "a", []byte{}},
+ {"TrimSuffix", []byte("☺"), "☺", []byte{}},
+}
+
+func TestTrim(t *testing.T) {
+ toFn := func(name string) (func([]byte, string) []byte, func([]byte, []byte) []byte) {
+ switch name {
+ case "Trim":
+ return Trim, nil
+ case "TrimLeft":
+ return TrimLeft, nil
+ case "TrimRight":
+ return TrimRight, nil
+ case "TrimPrefix":
+ return nil, TrimPrefix
+ case "TrimSuffix":
+ return nil, TrimSuffix
+ default:
+ t.Errorf("Undefined trim function %s", name)
+ return nil, nil
+ }
+ }
+
+ for _, tc := range trimTests {
+ name := tc.f
+ f, fb := toFn(name)
+ if f == nil && fb == nil {
+ continue
+ }
+ var actual string
+ if f != nil {
+ actual = string(f([]byte(tc.in), tc.arg))
+ } else {
+ actual = string(fb([]byte(tc.in), []byte(tc.arg)))
+ }
+ if actual != tc.out {
+ t.Errorf("%s(%q, %q) = %q; want %q", name, tc.in, tc.arg, actual, tc.out)
+ }
+ }
+
+ for _, tc := range trimNilTests {
+ name := tc.f
+ f, fb := toFn(name)
+ if f == nil && fb == nil {
+ continue
+ }
+ var actual []byte
+ if f != nil {
+ actual = f(tc.in, tc.arg)
+ } else {
+ actual = fb(tc.in, []byte(tc.arg))
+ }
+ report := func(s []byte) string {
+ if s == nil {
+ return "nil"
+ } else {
+ return fmt.Sprintf("%q", s)
+ }
+ }
+ if len(actual) != 0 {
+ t.Errorf("%s(%s, %q) returned non-empty value", name, report(tc.in), tc.arg)
+ } else {
+ actualNil := actual == nil
+ outNil := tc.out == nil
+ if actualNil != outNil {
+ t.Errorf("%s(%s, %q) got nil %t; want nil %t", name, report(tc.in), tc.arg, actualNil, outNil)
+ }
+ }
+ }
+}
+
+type predicate struct {
+ f func(r rune) bool
+ name string
+}
+
+var isSpace = predicate{unicode.IsSpace, "IsSpace"}
+var isDigit = predicate{unicode.IsDigit, "IsDigit"}
+var isUpper = predicate{unicode.IsUpper, "IsUpper"}
+var isValidRune = predicate{
+ func(r rune) bool {
+ return r != utf8.RuneError
+ },
+ "IsValidRune",
+}
+
+type TrimFuncTest struct {
+ f predicate
+ in string
+ trimOut []byte
+ leftOut []byte
+ rightOut []byte
+}
+
+func not(p predicate) predicate {
+ return predicate{
+ func(r rune) bool {
+ return !p.f(r)
+ },
+ "not " + p.name,
+ }
+}
+
+var trimFuncTests = []TrimFuncTest{
+ {isSpace, space + " hello " + space,
+ []byte("hello"),
+ []byte("hello " + space),
+ []byte(space + " hello")},
+ {isDigit, "\u0e50\u0e5212hello34\u0e50\u0e51",
+ []byte("hello"),
+ []byte("hello34\u0e50\u0e51"),
+ []byte("\u0e50\u0e5212hello")},
+ {isUpper, "\u2C6F\u2C6F\u2C6F\u2C6FABCDhelloEF\u2C6F\u2C6FGH\u2C6F\u2C6F",
+ []byte("hello"),
+ []byte("helloEF\u2C6F\u2C6FGH\u2C6F\u2C6F"),
+ []byte("\u2C6F\u2C6F\u2C6F\u2C6FABCDhello")},
+ {not(isSpace), "hello" + space + "hello",
+ []byte(space),
+ []byte(space + "hello"),
+ []byte("hello" + space)},
+ {not(isDigit), "hello\u0e50\u0e521234\u0e50\u0e51helo",
+ []byte("\u0e50\u0e521234\u0e50\u0e51"),
+ []byte("\u0e50\u0e521234\u0e50\u0e51helo"),
+ []byte("hello\u0e50\u0e521234\u0e50\u0e51")},
+ {isValidRune, "ab\xc0a\xc0cd",
+ []byte("\xc0a\xc0"),
+ []byte("\xc0a\xc0cd"),
+ []byte("ab\xc0a\xc0")},
+ {not(isValidRune), "\xc0a\xc0",
+ []byte("a"),
+ []byte("a\xc0"),
+ []byte("\xc0a")},
+ // The nils returned by TrimLeftFunc are odd behavior, but we need
+ // to preserve backwards compatibility.
+ {isSpace, "",
+ nil,
+ nil,
+ []byte("")},
+ {isSpace, " ",
+ nil,
+ nil,
+ []byte("")},
+}
+
+func TestTrimFunc(t *testing.T) {
+ for _, tc := range trimFuncTests {
+ trimmers := []struct {
+ name string
+ trim func(s []byte, f func(r rune) bool) []byte
+ out []byte
+ }{
+ {"TrimFunc", TrimFunc, tc.trimOut},
+ {"TrimLeftFunc", TrimLeftFunc, tc.leftOut},
+ {"TrimRightFunc", TrimRightFunc, tc.rightOut},
+ }
+ for _, trimmer := range trimmers {
+ actual := trimmer.trim([]byte(tc.in), tc.f.f)
+ if actual == nil && trimmer.out != nil {
+ t.Errorf("%s(%q, %q) = nil; want %q", trimmer.name, tc.in, tc.f.name, trimmer.out)
+ }
+ if actual != nil && trimmer.out == nil {
+ t.Errorf("%s(%q, %q) = %q; want nil", trimmer.name, tc.in, tc.f.name, actual)
+ }
+ if !Equal(actual, trimmer.out) {
+ t.Errorf("%s(%q, %q) = %q; want %q", trimmer.name, tc.in, tc.f.name, actual, trimmer.out)
+ }
+ }
+ }
+}
+
+type IndexFuncTest struct {
+ in string
+ f predicate
+ first, last int
+}
+
+var indexFuncTests = []IndexFuncTest{
+ {"", isValidRune, -1, -1},
+ {"abc", isDigit, -1, -1},
+ {"0123", isDigit, 0, 3},
+ {"a1b", isDigit, 1, 1},
+ {space, isSpace, 0, len(space) - 3}, // last rune in space is 3 bytes
+ {"\u0e50\u0e5212hello34\u0e50\u0e51", isDigit, 0, 18},
+ {"\u2C6F\u2C6F\u2C6F\u2C6FABCDhelloEF\u2C6F\u2C6FGH\u2C6F\u2C6F", isUpper, 0, 34},
+ {"12\u0e50\u0e52hello34\u0e50\u0e51", not(isDigit), 8, 12},
+
+ // tests of invalid UTF-8
+ {"\x801", isDigit, 1, 1},
+ {"\x80abc", isDigit, -1, -1},
+ {"\xc0a\xc0", isValidRune, 1, 1},
+ {"\xc0a\xc0", not(isValidRune), 0, 2},
+ {"\xc0☺\xc0", not(isValidRune), 0, 4},
+ {"\xc0☺\xc0\xc0", not(isValidRune), 0, 5},
+ {"ab\xc0a\xc0cd", not(isValidRune), 2, 4},
+ {"a\xe0\x80cd", not(isValidRune), 1, 2},
+}
+
+func TestIndexFunc(t *testing.T) {
+ for _, tc := range indexFuncTests {
+ first := IndexFunc([]byte(tc.in), tc.f.f)
+ if first != tc.first {
+ t.Errorf("IndexFunc(%q, %s) = %d; want %d", tc.in, tc.f.name, first, tc.first)
+ }
+ last := LastIndexFunc([]byte(tc.in), tc.f.f)
+ if last != tc.last {
+ t.Errorf("LastIndexFunc(%q, %s) = %d; want %d", tc.in, tc.f.name, last, tc.last)
+ }
+ }
+}
+
+type ReplaceTest struct {
+ in string
+ old, new string
+ n int
+ out string
+}
+
+var ReplaceTests = []ReplaceTest{
+ {"hello", "l", "L", 0, "hello"},
+ {"hello", "l", "L", -1, "heLLo"},
+ {"hello", "x", "X", -1, "hello"},
+ {"", "x", "X", -1, ""},
+ {"radar", "r", "", -1, "ada"},
+ {"", "", "<>", -1, "<>"},
+ {"banana", "a", "<>", -1, "b<>n<>n<>"},
+ {"banana", "a", "<>", 1, "b<>nana"},
+ {"banana", "a", "<>", 1000, "b<>n<>n<>"},
+ {"banana", "an", "<>", -1, "b<><>a"},
+ {"banana", "ana", "<>", -1, "b<>na"},
+ {"banana", "", "<>", -1, "<>b<>a<>n<>a<>n<>a<>"},
+ {"banana", "", "<>", 10, "<>b<>a<>n<>a<>n<>a<>"},
+ {"banana", "", "<>", 6, "<>b<>a<>n<>a<>n<>a"},
+ {"banana", "", "<>", 5, "<>b<>a<>n<>a<>na"},
+ {"banana", "", "<>", 1, "<>banana"},
+ {"banana", "a", "a", -1, "banana"},
+ {"banana", "a", "a", 1, "banana"},
+ {"☺☻☹", "", "<>", -1, "<>☺<>☻<>☹<>"},
+}
+
+func TestReplace(t *testing.T) {
+ for _, tt := range ReplaceTests {
+ var (
+ in = []byte(tt.in)
+ old = []byte(tt.old)
+ new = []byte(tt.new)
+ )
+ if !asan.Enabled {
+ allocs := testing.AllocsPerRun(10, func() { Replace(in, old, new, tt.n) })
+ if allocs > 1 {
+ t.Errorf("Replace(%q, %q, %q, %d) allocates %.2f objects", tt.in, tt.old, tt.new, tt.n, allocs)
+ }
+ }
+ in = append(in, ""...)
+ in = in[:len(tt.in)]
+ out := Replace(in, old, new, tt.n)
+ if s := string(out); s != tt.out {
+ t.Errorf("Replace(%q, %q, %q, %d) = %q, want %q", tt.in, tt.old, tt.new, tt.n, s, tt.out)
+ }
+ if cap(in) == cap(out) && &in[:1][0] == &out[:1][0] {
+ t.Errorf("Replace(%q, %q, %q, %d) didn't copy", tt.in, tt.old, tt.new, tt.n)
+ }
+ if tt.n == -1 {
+ out := ReplaceAll(in, old, new)
+ if s := string(out); s != tt.out {
+ t.Errorf("ReplaceAll(%q, %q, %q) = %q, want %q", tt.in, tt.old, tt.new, s, tt.out)
+ }
+ }
+ }
+}
+
+func FuzzReplace(f *testing.F) {
+ for _, tt := range ReplaceTests {
+ f.Add([]byte(tt.in), []byte(tt.old), []byte(tt.new), tt.n)
+ }
+ f.Fuzz(func(t *testing.T, in, old, new []byte, n int) {
+ differentImpl := func(in, old, new []byte, n int) []byte {
+ var out Buffer
+ if n < 0 {
+ n = math.MaxInt
+ }
+ for i := 0; i < len(in); {
+ if n == 0 {
+ out.Write(in[i:])
+ break
+ }
+ if HasPrefix(in[i:], old) {
+ out.Write(new)
+ i += len(old)
+ n--
+ if len(old) != 0 {
+ continue
+ }
+ if i == len(in) {
+ break
+ }
+ }
+ if len(old) == 0 {
+ _, length := utf8.DecodeRune(in[i:])
+ out.Write(in[i : i+length])
+ i += length
+ } else {
+ out.WriteByte(in[i])
+ i++
+ }
+ }
+ if len(old) == 0 && n != 0 {
+ out.Write(new)
+ }
+ return out.Bytes()
+ }
+ if simple, replace := differentImpl(in, old, new, n), Replace(in, old, new, n); !slices.Equal(simple, replace) {
+ t.Errorf("The two implementations do not match %q != %q for Replace(%q, %q, %q, %d)", simple, replace, in, old, new, n)
+ }
+ })
+}
+
+func BenchmarkReplace(b *testing.B) {
+ for _, tt := range ReplaceTests {
+ desc := fmt.Sprintf("%q %q %q %d", tt.in, tt.old, tt.new, tt.n)
+ var (
+ in = []byte(tt.in)
+ old = []byte(tt.old)
+ new = []byte(tt.new)
+ )
+ b.Run(desc, func(b *testing.B) {
+ b.ReportAllocs()
+ for b.Loop() {
+ Replace(in, old, new, tt.n)
+ }
+ })
+ }
+}
+
+type TitleTest struct {
+ in, out string
+}
+
+var TitleTests = []TitleTest{
+ {"", ""},
+ {"a", "A"},
+ {" aaa aaa aaa ", " Aaa Aaa Aaa "},
+ {" Aaa Aaa Aaa ", " Aaa Aaa Aaa "},
+ {"123a456", "123a456"},
+ {"double-blind", "Double-Blind"},
+ {"ÿøû", "Ÿøû"},
+ {"with_underscore", "With_underscore"},
+ {"unicode \xe2\x80\xa8 line separator", "Unicode \xe2\x80\xa8 Line Separator"},
+}
+
+func TestTitle(t *testing.T) {
+ for _, tt := range TitleTests {
+ if s := string(Title([]byte(tt.in))); s != tt.out {
+ t.Errorf("Title(%q) = %q, want %q", tt.in, s, tt.out)
+ }
+ }
+}
+
+var ToTitleTests = []TitleTest{
+ {"", ""},
+ {"a", "A"},
+ {" aaa aaa aaa ", " AAA AAA AAA "},
+ {" Aaa Aaa Aaa ", " AAA AAA AAA "},
+ {"123a456", "123A456"},
+ {"double-blind", "DOUBLE-BLIND"},
+ {"ÿøû", "ŸØÛ"},
+}
+
+func TestToTitle(t *testing.T) {
+ for _, tt := range ToTitleTests {
+ if s := string(ToTitle([]byte(tt.in))); s != tt.out {
+ t.Errorf("ToTitle(%q) = %q, want %q", tt.in, s, tt.out)
+ }
+ }
+}
+
+var EqualFoldTests = []struct {
+ s, t string
+ out bool
+}{
+ {"abc", "abc", true},
+ {"ABcd", "ABcd", true},
+ {"123abc", "123ABC", true},
+ {"αβδ", "ΑΒΔ", true},
+ {"abc", "xyz", false},
+ {"abc", "XYZ", false},
+ {"abcdefghijk", "abcdefghijX", false},
+ {"abcdefghijk", "abcdefghij\u212A", true},
+ {"abcdefghijK", "abcdefghij\u212A", true},
+ {"abcdefghijkz", "abcdefghij\u212Ay", false},
+ {"abcdefghijKz", "abcdefghij\u212Ay", false},
+}
+
+func TestEqualFold(t *testing.T) {
+ for _, tt := range EqualFoldTests {
+ if out := EqualFold([]byte(tt.s), []byte(tt.t)); out != tt.out {
+ t.Errorf("EqualFold(%#q, %#q) = %v, want %v", tt.s, tt.t, out, tt.out)
+ }
+ if out := EqualFold([]byte(tt.t), []byte(tt.s)); out != tt.out {
+ t.Errorf("EqualFold(%#q, %#q) = %v, want %v", tt.t, tt.s, out, tt.out)
+ }
+ }
+}
+
+var cutTests = []struct {
+ s, sep string
+ before, after string
+ found bool
+}{
+ {"abc", "b", "a", "c", true},
+ {"abc", "a", "", "bc", true},
+ {"abc", "c", "ab", "", true},
+ {"abc", "abc", "", "", true},
+ {"abc", "", "", "abc", true},
+ {"abc", "d", "abc", "", false},
+ {"", "d", "", "", false},
+ {"", "", "", "", true},
+}
+
+func TestCut(t *testing.T) {
+ for _, tt := range cutTests {
+ if before, after, found := Cut([]byte(tt.s), []byte(tt.sep)); string(before) != tt.before || string(after) != tt.after || found != tt.found {
+ t.Errorf("Cut(%q, %q) = %q, %q, %v, want %q, %q, %v", tt.s, tt.sep, before, after, found, tt.before, tt.after, tt.found)
+ }
+ }
+}
+
+var cutPrefixTests = []struct {
+ s, sep string
+ after string
+ found bool
+}{
+ {"abc", "a", "bc", true},
+ {"abc", "abc", "", true},
+ {"abc", "", "abc", true},
+ {"abc", "d", "abc", false},
+ {"", "d", "", false},
+ {"", "", "", true},
+}
+
+func TestCutPrefix(t *testing.T) {
+ for _, tt := range cutPrefixTests {
+ if after, found := CutPrefix([]byte(tt.s), []byte(tt.sep)); string(after) != tt.after || found != tt.found {
+ t.Errorf("CutPrefix(%q, %q) = %q, %v, want %q, %v", tt.s, tt.sep, after, found, tt.after, tt.found)
+ }
+ }
+}
+
+var cutSuffixTests = []struct {
+ s, sep string
+ before string
+ found bool
+}{
+ {"abc", "bc", "a", true},
+ {"abc", "abc", "", true},
+ {"abc", "", "abc", true},
+ {"abc", "d", "abc", false},
+ {"", "d", "", false},
+ {"", "", "", true},
+}
+
+func TestCutSuffix(t *testing.T) {
+ for _, tt := range cutSuffixTests {
+ if before, found := CutSuffix([]byte(tt.s), []byte(tt.sep)); string(before) != tt.before || found != tt.found {
+ t.Errorf("CutSuffix(%q, %q) = %q, %v, want %q, %v", tt.s, tt.sep, before, found, tt.before, tt.found)
+ }
+ }
+}
+
+func TestBufferGrowNegative(t *testing.T) {
+ defer func() {
+ if err := recover(); err == nil {
+ t.Fatal("Grow(-1) should have panicked")
+ }
+ }()
+ var b Buffer
+ b.Grow(-1)
+}
+
+func TestBufferTruncateNegative(t *testing.T) {
+ defer func() {
+ if err := recover(); err == nil {
+ t.Fatal("Truncate(-1) should have panicked")
+ }
+ }()
+ var b Buffer
+ b.Truncate(-1)
+}
+
+func TestBufferTruncateOutOfRange(t *testing.T) {
+ defer func() {
+ if err := recover(); err == nil {
+ t.Fatal("Truncate(20) should have panicked")
+ }
+ }()
+ var b Buffer
+ b.Write(make([]byte, 10))
+ b.Truncate(20)
+}
+
+var containsTests = []struct {
+ b, subslice []byte
+ want bool
+}{
+ {[]byte("hello"), []byte("hel"), true},
+ {[]byte("日本語"), []byte("日本"), true},
+ {[]byte("hello"), []byte("Hello, world"), false},
+ {[]byte("東京"), []byte("京東"), false},
+}
+
+func TestContains(t *testing.T) {
+ for _, tt := range containsTests {
+ if got := Contains(tt.b, tt.subslice); got != tt.want {
+ t.Errorf("Contains(%q, %q) = %v, want %v", tt.b, tt.subslice, got, tt.want)
+ }
+ }
+}
+
+var ContainsAnyTests = []struct {
+ b []byte
+ substr string
+ expected bool
+}{
+ {[]byte(""), "", false},
+ {[]byte(""), "a", false},
+ {[]byte(""), "abc", false},
+ {[]byte("a"), "", false},
+ {[]byte("a"), "a", true},
+ {[]byte("aaa"), "a", true},
+ {[]byte("abc"), "xyz", false},
+ {[]byte("abc"), "xcz", true},
+ {[]byte("a☺b☻c☹d"), "uvw☻xyz", true},
+ {[]byte("aRegExp*"), ".(|)*+?^$[]", true},
+ {[]byte(dots + dots + dots), " ", false},
+}
+
+func TestContainsAny(t *testing.T) {
+ for _, ct := range ContainsAnyTests {
+ if ContainsAny(ct.b, ct.substr) != ct.expected {
+ t.Errorf("ContainsAny(%s, %s) = %v, want %v",
+ ct.b, ct.substr, !ct.expected, ct.expected)
+ }
+ }
+}
+
+var ContainsRuneTests = []struct {
+ b []byte
+ r rune
+ expected bool
+}{
+ {[]byte(""), 'a', false},
+ {[]byte("a"), 'a', true},
+ {[]byte("aaa"), 'a', true},
+ {[]byte("abc"), 'y', false},
+ {[]byte("abc"), 'c', true},
+ {[]byte("a☺b☻c☹d"), 'x', false},
+ {[]byte("a☺b☻c☹d"), '☻', true},
+ {[]byte("aRegExp*"), '*', true},
+}
+
+func TestContainsRune(t *testing.T) {
+ for _, ct := range ContainsRuneTests {
+ if ContainsRune(ct.b, ct.r) != ct.expected {
+ t.Errorf("ContainsRune(%q, %q) = %v, want %v",
+ ct.b, ct.r, !ct.expected, ct.expected)
+ }
+ }
+}
+
+func TestContainsFunc(t *testing.T) {
+ for _, ct := range ContainsRuneTests {
+ if ContainsFunc(ct.b, func(r rune) bool {
+ return ct.r == r
+ }) != ct.expected {
+ t.Errorf("ContainsFunc(%q, func(%q)) = %v, want %v",
+ ct.b, ct.r, !ct.expected, ct.expected)
+ }
+ }
+}
+
+var makeFieldsInput = func() []byte {
+ x := make([]byte, 1<<20)
+ // Input is ~10% space, ~10% 2-byte UTF-8, rest ASCII non-space.
+ r := rand.New(rand.NewSource(99))
+ for i := range x {
+ switch r.Intn(10) {
+ case 0:
+ x[i] = ' '
+ case 1:
+ if i > 0 && x[i-1] == 'x' {
+ copy(x[i-1:], "χ")
+ break
+ }
+ fallthrough
+ default:
+ x[i] = 'x'
+ }
+ }
+ return x
+}
+
+var makeFieldsInputASCII = func() []byte {
+ x := make([]byte, 1<<20)
+ // Input is ~10% space, rest ASCII non-space.
+ r := rand.New(rand.NewSource(99))
+ for i := range x {
+ if r.Intn(10) == 0 {
+ x[i] = ' '
+ } else {
+ x[i] = 'x'
+ }
+ }
+ return x
+}
+
+var bytesdata = []struct {
+ name string
+ data []byte
+}{
+ {"ASCII", makeFieldsInputASCII()},
+ {"Mixed", makeFieldsInput()},
+}
+
+func BenchmarkFields(b *testing.B) {
+ for _, sd := range bytesdata {
+ b.Run(sd.name, func(b *testing.B) {
+ for j := 1 << 4; j <= 1<<20; j <<= 4 {
+ b.Run(fmt.Sprintf("%d", j), func(b *testing.B) {
+ b.ReportAllocs()
+ b.SetBytes(int64(j))
+ data := sd.data[:j]
+ for i := 0; i < b.N; i++ {
+ Fields(data)
+ }
+ })
+ }
+ })
+ }
+}
+
+func BenchmarkFieldsFunc(b *testing.B) {
+ for _, sd := range bytesdata {
+ b.Run(sd.name, func(b *testing.B) {
+ for j := 1 << 4; j <= 1<<20; j <<= 4 {
+ b.Run(fmt.Sprintf("%d", j), func(b *testing.B) {
+ b.ReportAllocs()
+ b.SetBytes(int64(j))
+ data := sd.data[:j]
+ for i := 0; i < b.N; i++ {
+ FieldsFunc(data, unicode.IsSpace)
+ }
+ })
+ }
+ })
+ }
+}
+
+func BenchmarkTrimSpace(b *testing.B) {
+ tests := []struct {
+ name string
+ input []byte
+ }{
+ {"NoTrim", []byte("typical")},
+ {"ASCII", []byte(" foo bar ")},
+ {"SomeNonASCII", []byte(" \u2000\t\r\n x\t\t\r\r\ny\n \u3000 ")},
+ {"JustNonASCII", []byte("\u2000\u2000\u2000☺☺☺☺\u3000\u3000\u3000")},
+ }
+ for _, test := range tests {
+ b.Run(test.name, func(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ TrimSpace(test.input)
+ }
+ })
+ }
+}
+
+func BenchmarkToValidUTF8(b *testing.B) {
+ tests := []struct {
+ name string
+ input []byte
+ }{
+ {"Valid", []byte("typical")},
+ {"InvalidASCII", []byte("foo\xffbar")},
+ {"InvalidNonASCII", []byte("日本語\xff日本語")},
+ }
+ replacement := []byte("\uFFFD")
+ b.ResetTimer()
+ for _, test := range tests {
+ b.Run(test.name, func(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ ToValidUTF8(test.input, replacement)
+ }
+ })
+ }
+}
+
+func makeBenchInputHard() []byte {
+ tokens := [...]string{
+ "", "", "", "",
+ "
", "
", "", "",
+ "hello", "world",
+ }
+ x := make([]byte, 0, 1<<20)
+ r := rand.New(rand.NewSource(99))
+ for {
+ i := r.Intn(len(tokens))
+ if len(x)+len(tokens[i]) >= 1<<20 {
+ break
+ }
+ x = append(x, tokens[i]...)
+ }
+ return x
+}
+
+var benchInputHard = makeBenchInputHard()
+
+func benchmarkIndexHard(b *testing.B, sep []byte) {
+ n := Index(benchInputHard, sep)
+ if n < 0 {
+ n = len(benchInputHard)
+ }
+ b.SetBytes(int64(n))
+ for i := 0; i < b.N; i++ {
+ Index(benchInputHard, sep)
+ }
+}
+
+func benchmarkLastIndexHard(b *testing.B, sep []byte) {
+ for i := 0; i < b.N; i++ {
+ LastIndex(benchInputHard, sep)
+ }
+}
+
+func benchmarkCountHard(b *testing.B, sep []byte) {
+ for i := 0; i < b.N; i++ {
+ Count(benchInputHard, sep)
+ }
+}
+
+func BenchmarkIndexHard1(b *testing.B) { benchmarkIndexHard(b, []byte("<>")) }
+func BenchmarkIndexHard2(b *testing.B) { benchmarkIndexHard(b, []byte("")) }
+func BenchmarkIndexHard3(b *testing.B) { benchmarkIndexHard(b, []byte("hello world")) }
+func BenchmarkIndexHard4(b *testing.B) {
+ benchmarkIndexHard(b, []byte("helloworld
"))
+}
+
+func BenchmarkLastIndexHard1(b *testing.B) { benchmarkLastIndexHard(b, []byte("<>")) }
+func BenchmarkLastIndexHard2(b *testing.B) { benchmarkLastIndexHard(b, []byte("")) }
+func BenchmarkLastIndexHard3(b *testing.B) { benchmarkLastIndexHard(b, []byte("hello world")) }
+
+func BenchmarkCountHard1(b *testing.B) { benchmarkCountHard(b, []byte("<>")) }
+func BenchmarkCountHard2(b *testing.B) { benchmarkCountHard(b, []byte("")) }
+func BenchmarkCountHard3(b *testing.B) { benchmarkCountHard(b, []byte("hello world")) }
+
+func BenchmarkSplitEmptySeparator(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ Split(benchInputHard, nil)
+ }
+}
+
+func BenchmarkSplitSingleByteSeparator(b *testing.B) {
+ sep := []byte("/")
+ for i := 0; i < b.N; i++ {
+ Split(benchInputHard, sep)
+ }
+}
+
+func BenchmarkSplitMultiByteSeparator(b *testing.B) {
+ sep := []byte("hello")
+ for i := 0; i < b.N; i++ {
+ Split(benchInputHard, sep)
+ }
+}
+
+func BenchmarkSplitNSingleByteSeparator(b *testing.B) {
+ sep := []byte("/")
+ for i := 0; i < b.N; i++ {
+ SplitN(benchInputHard, sep, 10)
+ }
+}
+
+func BenchmarkSplitNMultiByteSeparator(b *testing.B) {
+ sep := []byte("hello")
+ for i := 0; i < b.N; i++ {
+ SplitN(benchInputHard, sep, 10)
+ }
+}
+
+func BenchmarkRepeat(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ Repeat([]byte("-"), 80)
+ }
+}
+
+func BenchmarkRepeatLarge(b *testing.B) {
+ s := Repeat([]byte("@"), 8*1024)
+ for j := 8; j <= 30; j++ {
+ for _, k := range []int{1, 16, 4097} {
+ s := s[:k]
+ n := (1 << j) / k
+ if n == 0 {
+ continue
+ }
+ b.Run(fmt.Sprintf("%d/%d", 1< b[:1] failed")
+ }
+}
+
+func TestCompareBytes(t *testing.T) {
+ lengths := make([]int, 0) // lengths to test in ascending order
+ for i := 0; i <= 128; i++ {
+ lengths = append(lengths, i)
+ }
+ lengths = append(lengths, 256, 512, 1024, 1333, 4095, 4096, 4097)
+
+ if !testing.Short() {
+ lengths = append(lengths, 65535, 65536, 65537, 99999)
+ }
+
+ n := lengths[len(lengths)-1]
+ a := make([]byte, n+1)
+ b := make([]byte, n+1)
+ for _, len := range lengths {
+ // randomish but deterministic data. No 0 or 255.
+ for i := 0; i < len; i++ {
+ a[i] = byte(1 + 31*i%254)
+ b[i] = byte(1 + 31*i%254)
+ }
+ // data past the end is different
+ for i := len; i <= n; i++ {
+ a[i] = 8
+ b[i] = 9
+ }
+ cmp := Compare(a[:len], b[:len])
+ if cmp != 0 {
+ t.Errorf(`CompareIdentical(%d) = %d`, len, cmp)
+ }
+ if len > 0 {
+ cmp = Compare(a[:len-1], b[:len])
+ if cmp != -1 {
+ t.Errorf(`CompareAshorter(%d) = %d`, len, cmp)
+ }
+ cmp = Compare(a[:len], b[:len-1])
+ if cmp != 1 {
+ t.Errorf(`CompareBshorter(%d) = %d`, len, cmp)
+ }
+ }
+ for k := 0; k < len; k++ {
+ b[k] = a[k] - 1
+ cmp = Compare(a[:len], b[:len])
+ if cmp != 1 {
+ t.Errorf(`CompareAbigger(%d,%d) = %d`, len, k, cmp)
+ }
+ b[k] = a[k] + 1
+ cmp = Compare(a[:len], b[:len])
+ if cmp != -1 {
+ t.Errorf(`CompareBbigger(%d,%d) = %d`, len, k, cmp)
+ }
+ b[k] = a[k]
+ }
+ }
+}
+
+func TestEndianBaseCompare(t *testing.T) {
+ // This test compares byte slices that are almost identical, except one
+ // difference that for some j, a[j]>b[j] and a[j+1] b2 failed")
+ }
+ }
+}
+
+func BenchmarkCompareBytesEmpty(b *testing.B) {
+ b1 := []byte("")
+ b2 := b1
+ for i := 0; i < b.N; i++ {
+ if Compare(b1, b2) != 0 {
+ b.Fatal("b1 != b2")
+ }
+ }
+}
+
+func BenchmarkCompareBytesIdentical(b *testing.B) {
+ b1 := []byte("Hello Gophers!")
+ b2 := b1
+ for i := 0; i < b.N; i++ {
+ if Compare(b1, b2) != 0 {
+ b.Fatal("b1 != b2")
+ }
+ }
+}
+
+func BenchmarkCompareBytesSameLength(b *testing.B) {
+ b1 := []byte("Hello Gophers!")
+ b2 := []byte("Hello, Gophers")
+ for i := 0; i < b.N; i++ {
+ if Compare(b1, b2) != -1 {
+ b.Fatal("b1 < b2 failed")
+ }
+ }
+}
+
+func BenchmarkCompareBytesDifferentLength(b *testing.B) {
+ b1 := []byte("Hello Gophers!")
+ b2 := []byte("Hello, Gophers!")
+ for i := 0; i < b.N; i++ {
+ if Compare(b1, b2) != -1 {
+ b.Fatal("b1 < b2 failed")
+ }
+ }
+}
+
+func benchmarkCompareBytesBigUnaligned(b *testing.B, offset int) {
+ b.StopTimer()
+ b1 := make([]byte, 0, 1<<20)
+ for len(b1) < 1<<20 {
+ b1 = append(b1, "Hello Gophers!"...)
+ }
+ b2 := append([]byte("12345678")[:offset], b1...)
+ b.StartTimer()
+ for j := 0; j < b.N; j++ {
+ if Compare(b1, b2[offset:]) != 0 {
+ b.Fatal("b1 != b2")
+ }
+ }
+ b.SetBytes(int64(len(b1)))
+}
+
+func BenchmarkCompareBytesBigUnaligned(b *testing.B) {
+ for i := 1; i < 8; i++ {
+ b.Run(fmt.Sprintf("offset=%d", i), func(b *testing.B) {
+ benchmarkCompareBytesBigUnaligned(b, i)
+ })
+ }
+}
+
+func benchmarkCompareBytesBigBothUnaligned(b *testing.B, offset int) {
+ b.StopTimer()
+ pattern := []byte("Hello Gophers!")
+ b1 := make([]byte, 0, 1<<20+len(pattern))
+ for len(b1) < 1<<20 {
+ b1 = append(b1, pattern...)
+ }
+ b2 := make([]byte, len(b1))
+ copy(b2, b1)
+ b.StartTimer()
+ for j := 0; j < b.N; j++ {
+ if Compare(b1[offset:], b2[offset:]) != 0 {
+ b.Fatal("b1 != b2")
+ }
+ }
+ b.SetBytes(int64(len(b1[offset:])))
+}
+
+func BenchmarkCompareBytesBigBothUnaligned(b *testing.B) {
+ for i := 0; i < 8; i++ {
+ b.Run(fmt.Sprintf("offset=%d", i), func(b *testing.B) {
+ benchmarkCompareBytesBigBothUnaligned(b, i)
+ })
+ }
+}
+
+func BenchmarkCompareBytesBig(b *testing.B) {
+ b.StopTimer()
+ b1 := make([]byte, 0, 1<<20)
+ for len(b1) < 1<<20 {
+ b1 = append(b1, "Hello Gophers!"...)
+ }
+ b2 := append([]byte{}, b1...)
+ b.StartTimer()
+ for i := 0; i < b.N; i++ {
+ if Compare(b1, b2) != 0 {
+ b.Fatal("b1 != b2")
+ }
+ }
+ b.SetBytes(int64(len(b1)))
+}
+
+func BenchmarkCompareBytesBigIdentical(b *testing.B) {
+ b.StopTimer()
+ b1 := make([]byte, 0, 1<<20)
+ for len(b1) < 1<<20 {
+ b1 = append(b1, "Hello Gophers!"...)
+ }
+ b2 := b1
+ b.StartTimer()
+ for i := 0; i < b.N; i++ {
+ if Compare(b1, b2) != 0 {
+ b.Fatal("b1 != b2")
+ }
+ }
+ b.SetBytes(int64(len(b1)))
+}
diff --git a/go/src/bytes/example_test.go b/go/src/bytes/example_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..c489b950e59a913d794cd6f6d5568c21abe667c4
--- /dev/null
+++ b/go/src/bytes/example_test.go
@@ -0,0 +1,720 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bytes_test
+
+import (
+ "bytes"
+ "encoding/base64"
+ "fmt"
+ "io"
+ "os"
+ "slices"
+ "strconv"
+ "unicode"
+)
+
+func ExampleBuffer() {
+ var b bytes.Buffer // A Buffer needs no initialization.
+ b.Write([]byte("Hello "))
+ fmt.Fprintf(&b, "world!")
+ b.WriteTo(os.Stdout)
+ // Output: Hello world!
+}
+
+func ExampleBuffer_reader() {
+ // A Buffer can turn a string or a []byte into an io.Reader.
+ buf := bytes.NewBufferString("R29waGVycyBydWxlIQ==")
+ dec := base64.NewDecoder(base64.StdEncoding, buf)
+ io.Copy(os.Stdout, dec)
+ // Output: Gophers rule!
+}
+
+func ExampleBuffer_Bytes() {
+ buf := bytes.Buffer{}
+ buf.Write([]byte{'h', 'e', 'l', 'l', 'o', ' ', 'w', 'o', 'r', 'l', 'd'})
+ os.Stdout.Write(buf.Bytes())
+ // Output: hello world
+}
+
+func ExampleBuffer_AvailableBuffer() {
+ var buf bytes.Buffer
+ for i := 0; i < 4; i++ {
+ b := buf.AvailableBuffer()
+ b = strconv.AppendInt(b, int64(i), 10)
+ b = append(b, ' ')
+ buf.Write(b)
+ }
+ os.Stdout.Write(buf.Bytes())
+ // Output: 0 1 2 3
+}
+
+func ExampleBuffer_Cap() {
+ buf1 := bytes.NewBuffer(make([]byte, 10))
+ buf2 := bytes.NewBuffer(make([]byte, 0, 10))
+ fmt.Println(buf1.Cap())
+ fmt.Println(buf2.Cap())
+ // Output:
+ // 10
+ // 10
+}
+
+func ExampleBuffer_Grow() {
+ var b bytes.Buffer
+ b.Grow(64)
+ bb := b.Bytes()
+ b.Write([]byte("64 bytes or fewer"))
+ fmt.Printf("%q", bb[:b.Len()])
+ // Output: "64 bytes or fewer"
+}
+
+func ExampleBuffer_Len() {
+ var b bytes.Buffer
+ b.Grow(64)
+ b.Write([]byte("abcde"))
+ fmt.Printf("%d", b.Len())
+ // Output: 5
+}
+
+func ExampleBuffer_Next() {
+ var b bytes.Buffer
+ b.Grow(64)
+ b.Write([]byte("abcde"))
+ fmt.Printf("%s\n", b.Next(2))
+ fmt.Printf("%s\n", b.Next(2))
+ fmt.Printf("%s", b.Next(2))
+ // Output:
+ // ab
+ // cd
+ // e
+}
+
+func ExampleBuffer_Read() {
+ var b bytes.Buffer
+ b.Grow(64)
+ b.Write([]byte("abcde"))
+ rdbuf := make([]byte, 1)
+ n, err := b.Read(rdbuf)
+ if err != nil {
+ panic(err)
+ }
+ fmt.Println(n)
+ fmt.Println(b.String())
+ fmt.Println(string(rdbuf))
+ // Output:
+ // 1
+ // bcde
+ // a
+}
+
+func ExampleBuffer_ReadByte() {
+ var b bytes.Buffer
+ b.Grow(64)
+ b.Write([]byte("abcde"))
+ c, err := b.ReadByte()
+ if err != nil {
+ panic(err)
+ }
+ fmt.Println(c)
+ fmt.Println(b.String())
+ // Output:
+ // 97
+ // bcde
+}
+
+func ExampleClone() {
+ b := []byte("abc")
+ clone := bytes.Clone(b)
+ fmt.Printf("%s\n", clone)
+ clone[0] = 'd'
+ fmt.Printf("%s\n", b)
+ fmt.Printf("%s\n", clone)
+ // Output:
+ // abc
+ // abc
+ // dbc
+}
+
+func ExampleCompare() {
+ // Interpret Compare's result by comparing it to zero.
+ var a, b []byte
+ if bytes.Compare(a, b) < 0 {
+ // a less b
+ }
+ if bytes.Compare(a, b) <= 0 {
+ // a less or equal b
+ }
+ if bytes.Compare(a, b) > 0 {
+ // a greater b
+ }
+ if bytes.Compare(a, b) >= 0 {
+ // a greater or equal b
+ }
+
+ // Prefer Equal to Compare for equality comparisons.
+ if bytes.Equal(a, b) {
+ // a equal b
+ }
+ if !bytes.Equal(a, b) {
+ // a not equal b
+ }
+}
+
+func ExampleCompare_search() {
+ // Binary search to find a matching byte slice.
+ var needle []byte
+ var haystack [][]byte // Assume sorted
+ _, found := slices.BinarySearchFunc(haystack, needle, bytes.Compare)
+ if found {
+ // Found it!
+ }
+}
+
+func ExampleContains() {
+ fmt.Println(bytes.Contains([]byte("seafood"), []byte("foo")))
+ fmt.Println(bytes.Contains([]byte("seafood"), []byte("bar")))
+ fmt.Println(bytes.Contains([]byte("seafood"), []byte("")))
+ fmt.Println(bytes.Contains([]byte(""), []byte("")))
+ // Output:
+ // true
+ // false
+ // true
+ // true
+}
+
+func ExampleContainsAny() {
+ fmt.Println(bytes.ContainsAny([]byte("I like seafood."), "fÄo!"))
+ fmt.Println(bytes.ContainsAny([]byte("I like seafood."), "去是伟大的."))
+ fmt.Println(bytes.ContainsAny([]byte("I like seafood."), ""))
+ fmt.Println(bytes.ContainsAny([]byte(""), ""))
+ // Output:
+ // true
+ // true
+ // false
+ // false
+}
+
+func ExampleContainsRune() {
+ fmt.Println(bytes.ContainsRune([]byte("I like seafood."), 'f'))
+ fmt.Println(bytes.ContainsRune([]byte("I like seafood."), 'ö'))
+ fmt.Println(bytes.ContainsRune([]byte("去是伟大的!"), '大'))
+ fmt.Println(bytes.ContainsRune([]byte("去是伟大的!"), '!'))
+ fmt.Println(bytes.ContainsRune([]byte(""), '@'))
+ // Output:
+ // true
+ // false
+ // true
+ // true
+ // false
+}
+
+func ExampleContainsFunc() {
+ f := func(r rune) bool {
+ return r >= 'a' && r <= 'z'
+ }
+ fmt.Println(bytes.ContainsFunc([]byte("HELLO"), f))
+ fmt.Println(bytes.ContainsFunc([]byte("World"), f))
+ // Output:
+ // false
+ // true
+}
+
+func ExampleCount() {
+ fmt.Println(bytes.Count([]byte("cheese"), []byte("e")))
+ fmt.Println(bytes.Count([]byte("five"), []byte(""))) // before & after each rune
+ // Output:
+ // 3
+ // 5
+}
+
+func ExampleCut() {
+ show := func(s, sep string) {
+ before, after, found := bytes.Cut([]byte(s), []byte(sep))
+ fmt.Printf("Cut(%q, %q) = %q, %q, %v\n", s, sep, before, after, found)
+ }
+ show("Gopher", "Go")
+ show("Gopher", "ph")
+ show("Gopher", "er")
+ show("Gopher", "Badger")
+ // Output:
+ // Cut("Gopher", "Go") = "", "pher", true
+ // Cut("Gopher", "ph") = "Go", "er", true
+ // Cut("Gopher", "er") = "Goph", "", true
+ // Cut("Gopher", "Badger") = "Gopher", "", false
+}
+
+func ExampleCutPrefix() {
+ show := func(s, prefix string) {
+ after, found := bytes.CutPrefix([]byte(s), []byte(prefix))
+ fmt.Printf("CutPrefix(%q, %q) = %q, %v\n", s, prefix, after, found)
+ }
+ show("Gopher", "Go")
+ show("Gopher", "ph")
+ // Output:
+ // CutPrefix("Gopher", "Go") = "pher", true
+ // CutPrefix("Gopher", "ph") = "Gopher", false
+}
+
+func ExampleCutSuffix() {
+ show := func(s, suffix string) {
+ before, found := bytes.CutSuffix([]byte(s), []byte(suffix))
+ fmt.Printf("CutSuffix(%q, %q) = %q, %v\n", s, suffix, before, found)
+ }
+ show("Gopher", "Go")
+ show("Gopher", "er")
+ // Output:
+ // CutSuffix("Gopher", "Go") = "Gopher", false
+ // CutSuffix("Gopher", "er") = "Goph", true
+}
+
+func ExampleEqual() {
+ fmt.Println(bytes.Equal([]byte("Go"), []byte("Go")))
+ fmt.Println(bytes.Equal([]byte("Go"), []byte("C++")))
+ // Output:
+ // true
+ // false
+}
+
+func ExampleEqualFold() {
+ fmt.Println(bytes.EqualFold([]byte("Go"), []byte("go")))
+ // Output: true
+}
+
+func ExampleFields() {
+ fmt.Printf("Fields are: %q", bytes.Fields([]byte(" foo bar baz ")))
+ // Output: Fields are: ["foo" "bar" "baz"]
+}
+
+func ExampleFieldsFunc() {
+ f := func(c rune) bool {
+ return !unicode.IsLetter(c) && !unicode.IsNumber(c)
+ }
+ fmt.Printf("Fields are: %q", bytes.FieldsFunc([]byte(" foo1;bar2,baz3..."), f))
+ // Output: Fields are: ["foo1" "bar2" "baz3"]
+}
+
+func ExampleHasPrefix() {
+ fmt.Println(bytes.HasPrefix([]byte("Gopher"), []byte("Go")))
+ fmt.Println(bytes.HasPrefix([]byte("Gopher"), []byte("C")))
+ fmt.Println(bytes.HasPrefix([]byte("Gopher"), []byte("")))
+ // Output:
+ // true
+ // false
+ // true
+}
+
+func ExampleHasSuffix() {
+ fmt.Println(bytes.HasSuffix([]byte("Amigo"), []byte("go")))
+ fmt.Println(bytes.HasSuffix([]byte("Amigo"), []byte("O")))
+ fmt.Println(bytes.HasSuffix([]byte("Amigo"), []byte("Ami")))
+ fmt.Println(bytes.HasSuffix([]byte("Amigo"), []byte("")))
+ // Output:
+ // true
+ // false
+ // false
+ // true
+}
+
+func ExampleIndex() {
+ fmt.Println(bytes.Index([]byte("chicken"), []byte("ken")))
+ fmt.Println(bytes.Index([]byte("chicken"), []byte("dmr")))
+ // Output:
+ // 4
+ // -1
+}
+
+func ExampleIndexByte() {
+ fmt.Println(bytes.IndexByte([]byte("chicken"), byte('k')))
+ fmt.Println(bytes.IndexByte([]byte("chicken"), byte('g')))
+ // Output:
+ // 4
+ // -1
+}
+
+func ExampleIndexFunc() {
+ f := func(c rune) bool {
+ return unicode.Is(unicode.Han, c)
+ }
+ fmt.Println(bytes.IndexFunc([]byte("Hello, 世界"), f))
+ fmt.Println(bytes.IndexFunc([]byte("Hello, world"), f))
+ // Output:
+ // 7
+ // -1
+}
+
+func ExampleIndexAny() {
+ fmt.Println(bytes.IndexAny([]byte("chicken"), "aeiouy"))
+ fmt.Println(bytes.IndexAny([]byte("crwth"), "aeiouy"))
+ // Output:
+ // 2
+ // -1
+}
+
+func ExampleIndexRune() {
+ fmt.Println(bytes.IndexRune([]byte("chicken"), 'k'))
+ fmt.Println(bytes.IndexRune([]byte("chicken"), 'd'))
+ // Output:
+ // 4
+ // -1
+}
+
+func ExampleJoin() {
+ s := [][]byte{[]byte("foo"), []byte("bar"), []byte("baz")}
+ fmt.Printf("%s", bytes.Join(s, []byte(", ")))
+ // Output: foo, bar, baz
+}
+
+func ExampleLastIndex() {
+ fmt.Println(bytes.Index([]byte("go gopher"), []byte("go")))
+ fmt.Println(bytes.LastIndex([]byte("go gopher"), []byte("go")))
+ fmt.Println(bytes.LastIndex([]byte("go gopher"), []byte("rodent")))
+ // Output:
+ // 0
+ // 3
+ // -1
+}
+
+func ExampleLastIndexAny() {
+ fmt.Println(bytes.LastIndexAny([]byte("go gopher"), "MüQp"))
+ fmt.Println(bytes.LastIndexAny([]byte("go 地鼠"), "地大"))
+ fmt.Println(bytes.LastIndexAny([]byte("go gopher"), "z,!."))
+ // Output:
+ // 5
+ // 3
+ // -1
+}
+
+func ExampleLastIndexByte() {
+ fmt.Println(bytes.LastIndexByte([]byte("go gopher"), byte('g')))
+ fmt.Println(bytes.LastIndexByte([]byte("go gopher"), byte('r')))
+ fmt.Println(bytes.LastIndexByte([]byte("go gopher"), byte('z')))
+ // Output:
+ // 3
+ // 8
+ // -1
+}
+
+func ExampleLastIndexFunc() {
+ fmt.Println(bytes.LastIndexFunc([]byte("go gopher!"), unicode.IsLetter))
+ fmt.Println(bytes.LastIndexFunc([]byte("go gopher!"), unicode.IsPunct))
+ fmt.Println(bytes.LastIndexFunc([]byte("go gopher!"), unicode.IsNumber))
+ // Output:
+ // 8
+ // 9
+ // -1
+}
+
+func ExampleMap() {
+ rot13 := func(r rune) rune {
+ switch {
+ case r >= 'A' && r <= 'Z':
+ return 'A' + (r-'A'+13)%26
+ case r >= 'a' && r <= 'z':
+ return 'a' + (r-'a'+13)%26
+ }
+ return r
+ }
+ fmt.Printf("%s\n", bytes.Map(rot13, []byte("'Twas brillig and the slithy gopher...")))
+ // Output:
+ // 'Gjnf oevyyvt naq gur fyvgul tbcure...
+}
+
+func ExampleReader_Len() {
+ fmt.Println(bytes.NewReader([]byte("Hi!")).Len())
+ fmt.Println(bytes.NewReader([]byte("こんにちは!")).Len())
+ // Output:
+ // 3
+ // 16
+}
+
+func ExampleRepeat() {
+ fmt.Printf("ba%s", bytes.Repeat([]byte("na"), 2))
+ // Output: banana
+}
+
+func ExampleReplace() {
+ fmt.Printf("%s\n", bytes.Replace([]byte("oink oink oink"), []byte("k"), []byte("ky"), 2))
+ fmt.Printf("%s\n", bytes.Replace([]byte("oink oink oink"), []byte("oink"), []byte("moo"), -1))
+ // Output:
+ // oinky oinky oink
+ // moo moo moo
+}
+
+func ExampleReplaceAll() {
+ fmt.Printf("%s\n", bytes.ReplaceAll([]byte("oink oink oink"), []byte("oink"), []byte("moo")))
+ // Output:
+ // moo moo moo
+}
+
+func ExampleRunes() {
+ rs := bytes.Runes([]byte("go gopher"))
+ for _, r := range rs {
+ fmt.Printf("%#U\n", r)
+ }
+ // Output:
+ // U+0067 'g'
+ // U+006F 'o'
+ // U+0020 ' '
+ // U+0067 'g'
+ // U+006F 'o'
+ // U+0070 'p'
+ // U+0068 'h'
+ // U+0065 'e'
+ // U+0072 'r'
+}
+
+func ExampleSplit() {
+ fmt.Printf("%q\n", bytes.Split([]byte("a,b,c"), []byte(",")))
+ fmt.Printf("%q\n", bytes.Split([]byte("a man a plan a canal panama"), []byte("a ")))
+ fmt.Printf("%q\n", bytes.Split([]byte(" xyz "), []byte("")))
+ fmt.Printf("%q\n", bytes.Split([]byte(""), []byte("Bernardo O'Higgins")))
+ // Output:
+ // ["a" "b" "c"]
+ // ["" "man " "plan " "canal panama"]
+ // [" " "x" "y" "z" " "]
+ // [""]
+}
+
+func ExampleSplitN() {
+ fmt.Printf("%q\n", bytes.SplitN([]byte("a,b,c"), []byte(","), 2))
+ z := bytes.SplitN([]byte("a,b,c"), []byte(","), 0)
+ fmt.Printf("%q (nil = %v)\n", z, z == nil)
+ // Output:
+ // ["a" "b,c"]
+ // [] (nil = true)
+}
+
+func ExampleSplitAfter() {
+ fmt.Printf("%q\n", bytes.SplitAfter([]byte("a,b,c"), []byte(",")))
+ // Output: ["a," "b," "c"]
+}
+
+func ExampleSplitAfterN() {
+ fmt.Printf("%q\n", bytes.SplitAfterN([]byte("a,b,c"), []byte(","), 2))
+ // Output: ["a," "b,c"]
+}
+
+func ExampleTitle() {
+ fmt.Printf("%s", bytes.Title([]byte("her royal highness")))
+ // Output: Her Royal Highness
+}
+
+func ExampleToTitle() {
+ fmt.Printf("%s\n", bytes.ToTitle([]byte("loud noises")))
+ fmt.Printf("%s\n", bytes.ToTitle([]byte("брат")))
+ // Output:
+ // LOUD NOISES
+ // БРАТ
+}
+
+func ExampleToTitleSpecial() {
+ str := []byte("ahoj vývojári golang")
+ totitle := bytes.ToTitleSpecial(unicode.AzeriCase, str)
+ fmt.Println("Original : " + string(str))
+ fmt.Println("ToTitle : " + string(totitle))
+ // Output:
+ // Original : ahoj vývojári golang
+ // ToTitle : AHOJ VÝVOJÁRİ GOLANG
+}
+
+func ExampleToValidUTF8() {
+ fmt.Printf("%s\n", bytes.ToValidUTF8([]byte("abc"), []byte("\uFFFD")))
+ fmt.Printf("%s\n", bytes.ToValidUTF8([]byte("a\xffb\xC0\xAFc\xff"), []byte("")))
+ fmt.Printf("%s\n", bytes.ToValidUTF8([]byte("\xed\xa0\x80"), []byte("abc")))
+ // Output:
+ // abc
+ // abc
+ // abc
+}
+
+func ExampleTrim() {
+ fmt.Printf("[%q]", bytes.Trim([]byte(" !!! Achtung! Achtung! !!! "), "! "))
+ // Output: ["Achtung! Achtung"]
+}
+
+func ExampleTrimFunc() {
+ fmt.Println(string(bytes.TrimFunc([]byte("go-gopher!"), unicode.IsLetter)))
+ fmt.Println(string(bytes.TrimFunc([]byte("\"go-gopher!\""), unicode.IsLetter)))
+ fmt.Println(string(bytes.TrimFunc([]byte("go-gopher!"), unicode.IsPunct)))
+ fmt.Println(string(bytes.TrimFunc([]byte("1234go-gopher!567"), unicode.IsNumber)))
+ // Output:
+ // -gopher!
+ // "go-gopher!"
+ // go-gopher
+ // go-gopher!
+}
+
+func ExampleTrimLeft() {
+ fmt.Print(string(bytes.TrimLeft([]byte("453gopher8257"), "0123456789")))
+ // Output:
+ // gopher8257
+}
+
+func ExampleTrimLeftFunc() {
+ fmt.Println(string(bytes.TrimLeftFunc([]byte("go-gopher"), unicode.IsLetter)))
+ fmt.Println(string(bytes.TrimLeftFunc([]byte("go-gopher!"), unicode.IsPunct)))
+ fmt.Println(string(bytes.TrimLeftFunc([]byte("1234go-gopher!567"), unicode.IsNumber)))
+ // Output:
+ // -gopher
+ // go-gopher!
+ // go-gopher!567
+}
+
+func ExampleTrimPrefix() {
+ var b = []byte("Goodbye,, world!")
+ b = bytes.TrimPrefix(b, []byte("Goodbye,"))
+ b = bytes.TrimPrefix(b, []byte("See ya,"))
+ fmt.Printf("Hello%s", b)
+ // Output: Hello, world!
+}
+
+func ExampleTrimSpace() {
+ fmt.Printf("%s", bytes.TrimSpace([]byte(" \t\n a lone gopher \n\t\r\n")))
+ // Output: a lone gopher
+}
+
+func ExampleTrimSuffix() {
+ var b = []byte("Hello, goodbye, etc!")
+ b = bytes.TrimSuffix(b, []byte("goodbye, etc!"))
+ b = bytes.TrimSuffix(b, []byte("gopher"))
+ b = append(b, bytes.TrimSuffix([]byte("world!"), []byte("x!"))...)
+ os.Stdout.Write(b)
+ // Output: Hello, world!
+}
+
+func ExampleTrimRight() {
+ fmt.Print(string(bytes.TrimRight([]byte("453gopher8257"), "0123456789")))
+ // Output:
+ // 453gopher
+}
+
+func ExampleTrimRightFunc() {
+ fmt.Println(string(bytes.TrimRightFunc([]byte("go-gopher"), unicode.IsLetter)))
+ fmt.Println(string(bytes.TrimRightFunc([]byte("go-gopher!"), unicode.IsPunct)))
+ fmt.Println(string(bytes.TrimRightFunc([]byte("1234go-gopher!567"), unicode.IsNumber)))
+ // Output:
+ // go-
+ // go-gopher
+ // 1234go-gopher!
+}
+
+func ExampleToLower() {
+ fmt.Printf("%s", bytes.ToLower([]byte("Gopher")))
+ // Output: gopher
+}
+
+func ExampleToLowerSpecial() {
+ str := []byte("AHOJ VÝVOJÁRİ GOLANG")
+ totitle := bytes.ToLowerSpecial(unicode.AzeriCase, str)
+ fmt.Println("Original : " + string(str))
+ fmt.Println("ToLower : " + string(totitle))
+ // Output:
+ // Original : AHOJ VÝVOJÁRİ GOLANG
+ // ToLower : ahoj vývojári golang
+}
+
+func ExampleToUpper() {
+ fmt.Printf("%s", bytes.ToUpper([]byte("Gopher")))
+ // Output: GOPHER
+}
+
+func ExampleToUpperSpecial() {
+ str := []byte("ahoj vývojári golang")
+ totitle := bytes.ToUpperSpecial(unicode.AzeriCase, str)
+ fmt.Println("Original : " + string(str))
+ fmt.Println("ToUpper : " + string(totitle))
+ // Output:
+ // Original : ahoj vývojári golang
+ // ToUpper : AHOJ VÝVOJÁRİ GOLANG
+}
+
+func ExampleLines() {
+ text := []byte("Hello\nWorld\nGo Programming\n")
+ for line := range bytes.Lines(text) {
+ fmt.Printf("%q\n", line)
+ }
+
+ // Output:
+ // "Hello\n"
+ // "World\n"
+ // "Go Programming\n"
+}
+
+func ExampleSplitSeq() {
+ s := []byte("a,b,c,d")
+ for part := range bytes.SplitSeq(s, []byte(",")) {
+ fmt.Printf("%q\n", part)
+ }
+
+ // Output:
+ // "a"
+ // "b"
+ // "c"
+ // "d"
+}
+
+func ExampleSplitAfterSeq() {
+ s := []byte("a,b,c,d")
+ for part := range bytes.SplitAfterSeq(s, []byte(",")) {
+ fmt.Printf("%q\n", part)
+ }
+
+ // Output:
+ // "a,"
+ // "b,"
+ // "c,"
+ // "d"
+}
+
+func ExampleFieldsSeq() {
+ text := []byte("The quick brown fox")
+ fmt.Println("Split byte slice into fields:")
+ for word := range bytes.FieldsSeq(text) {
+ fmt.Printf("%q\n", word)
+ }
+
+ textWithSpaces := []byte(" lots of spaces ")
+ fmt.Println("\nSplit byte slice with multiple spaces:")
+ for word := range bytes.FieldsSeq(textWithSpaces) {
+ fmt.Printf("%q\n", word)
+ }
+
+ // Output:
+ // Split byte slice into fields:
+ // "The"
+ // "quick"
+ // "brown"
+ // "fox"
+ //
+ // Split byte slice with multiple spaces:
+ // "lots"
+ // "of"
+ // "spaces"
+}
+
+func ExampleFieldsFuncSeq() {
+ text := []byte("The quick brown fox")
+ fmt.Println("Split on whitespace(similar to FieldsSeq):")
+ for word := range bytes.FieldsFuncSeq(text, unicode.IsSpace) {
+ fmt.Printf("%q\n", word)
+ }
+
+ mixedText := []byte("abc123def456ghi")
+ fmt.Println("\nSplit on digits:")
+ for word := range bytes.FieldsFuncSeq(mixedText, unicode.IsDigit) {
+ fmt.Printf("%q\n", word)
+ }
+
+ // Output:
+ // Split on whitespace(similar to FieldsSeq):
+ // "The"
+ // "quick"
+ // "brown"
+ // "fox"
+ //
+ // Split on digits:
+ // "abc"
+ // "def"
+ // "ghi"
+}
diff --git a/go/src/bytes/export_test.go b/go/src/bytes/export_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..b65428d9ce84894e05ecd063fa2a53b803a2c9f8
--- /dev/null
+++ b/go/src/bytes/export_test.go
@@ -0,0 +1,8 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bytes
+
+// Export func for testing
+var IndexBytePortable = indexBytePortable
diff --git a/go/src/bytes/iter.go b/go/src/bytes/iter.go
new file mode 100644
index 0000000000000000000000000000000000000000..a4ece881d20fa1ed10490d1e43dbb9179899c013
--- /dev/null
+++ b/go/src/bytes/iter.go
@@ -0,0 +1,137 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bytes
+
+import (
+ "iter"
+ "unicode"
+ "unicode/utf8"
+)
+
+// Lines returns an iterator over the newline-terminated lines in the byte slice s.
+// The lines yielded by the iterator include their terminating newlines.
+// If s is empty, the iterator yields no lines at all.
+// If s does not end in a newline, the final yielded line will not end in a newline.
+// It returns a single-use iterator.
+func Lines(s []byte) iter.Seq[[]byte] {
+ return func(yield func([]byte) bool) {
+ for len(s) > 0 {
+ var line []byte
+ if i := IndexByte(s, '\n'); i >= 0 {
+ line, s = s[:i+1], s[i+1:]
+ } else {
+ line, s = s, nil
+ }
+ if !yield(line[:len(line):len(line)]) {
+ return
+ }
+ }
+ }
+}
+
+// splitSeq is SplitSeq or SplitAfterSeq, configured by how many
+// bytes of sep to include in the results (none or all).
+func splitSeq(s, sep []byte, sepSave int) iter.Seq[[]byte] {
+ return func(yield func([]byte) bool) {
+ if len(sep) == 0 {
+ for len(s) > 0 {
+ _, size := utf8.DecodeRune(s)
+ if !yield(s[:size:size]) {
+ return
+ }
+ s = s[size:]
+ }
+ return
+ }
+ for {
+ i := Index(s, sep)
+ if i < 0 {
+ break
+ }
+ frag := s[:i+sepSave]
+ if !yield(frag[:len(frag):len(frag)]) {
+ return
+ }
+ s = s[i+len(sep):]
+ }
+ yield(s[:len(s):len(s)])
+ }
+}
+
+// SplitSeq returns an iterator over all subslices of s separated by sep.
+// The iterator yields the same subslices that would be returned by [Split](s, sep),
+// but without constructing a new slice containing the subslices.
+// It returns a single-use iterator.
+func SplitSeq(s, sep []byte) iter.Seq[[]byte] {
+ return splitSeq(s, sep, 0)
+}
+
+// SplitAfterSeq returns an iterator over subslices of s split after each instance of sep.
+// The iterator yields the same subslices that would be returned by [SplitAfter](s, sep),
+// but without constructing a new slice containing the subslices.
+// It returns a single-use iterator.
+func SplitAfterSeq(s, sep []byte) iter.Seq[[]byte] {
+ return splitSeq(s, sep, len(sep))
+}
+
+// FieldsSeq returns an iterator over subslices of s split around runs of
+// whitespace characters, as defined by [unicode.IsSpace].
+// The iterator yields the same subslices that would be returned by [Fields](s),
+// but without constructing a new slice containing the subslices.
+func FieldsSeq(s []byte) iter.Seq[[]byte] {
+ return func(yield func([]byte) bool) {
+ start := -1
+ for i := 0; i < len(s); {
+ size := 1
+ r := rune(s[i])
+ isSpace := asciiSpace[s[i]] != 0
+ if r >= utf8.RuneSelf {
+ r, size = utf8.DecodeRune(s[i:])
+ isSpace = unicode.IsSpace(r)
+ }
+ if isSpace {
+ if start >= 0 {
+ if !yield(s[start:i:i]) {
+ return
+ }
+ start = -1
+ }
+ } else if start < 0 {
+ start = i
+ }
+ i += size
+ }
+ if start >= 0 {
+ yield(s[start:len(s):len(s)])
+ }
+ }
+}
+
+// FieldsFuncSeq returns an iterator over subslices of s split around runs of
+// Unicode code points satisfying f(c).
+// The iterator yields the same subslices that would be returned by [FieldsFunc](s),
+// but without constructing a new slice containing the subslices.
+func FieldsFuncSeq(s []byte, f func(rune) bool) iter.Seq[[]byte] {
+ return func(yield func([]byte) bool) {
+ start := -1
+ for i := 0; i < len(s); {
+ r, size := utf8.DecodeRune(s[i:])
+ if f(r) {
+ if start >= 0 {
+ if !yield(s[start:i:i]) {
+ return
+ }
+ start = -1
+ }
+ } else if start < 0 {
+ start = i
+ }
+ i += size
+ }
+ if start >= 0 {
+ yield(s[start:len(s):len(s)])
+ }
+ }
+}
diff --git a/go/src/bytes/iter_test.go b/go/src/bytes/iter_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..e37fdfb96d1b615a481920318e33cd76fd10b089
--- /dev/null
+++ b/go/src/bytes/iter_test.go
@@ -0,0 +1,56 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bytes_test
+
+import (
+ . "bytes"
+ "testing"
+)
+
+func BenchmarkSplitSeqEmptySeparator(b *testing.B) {
+ for range b.N {
+ for range SplitSeq(benchInputHard, nil) {
+ }
+ }
+}
+
+func BenchmarkSplitSeqSingleByteSeparator(b *testing.B) {
+ sep := []byte("/")
+ for range b.N {
+ for range SplitSeq(benchInputHard, sep) {
+ }
+ }
+}
+
+func BenchmarkSplitSeqMultiByteSeparator(b *testing.B) {
+ sep := []byte("hello")
+ for range b.N {
+ for range SplitSeq(benchInputHard, sep) {
+ }
+ }
+}
+
+func BenchmarkSplitAfterSeqEmptySeparator(b *testing.B) {
+ for range b.N {
+ for range SplitAfterSeq(benchInputHard, nil) {
+ }
+ }
+}
+
+func BenchmarkSplitAfterSeqSingleByteSeparator(b *testing.B) {
+ sep := []byte("/")
+ for range b.N {
+ for range SplitAfterSeq(benchInputHard, sep) {
+ }
+ }
+}
+
+func BenchmarkSplitAfterSeqMultiByteSeparator(b *testing.B) {
+ sep := []byte("hello")
+ for range b.N {
+ for range SplitAfterSeq(benchInputHard, sep) {
+ }
+ }
+}
diff --git a/go/src/bytes/reader.go b/go/src/bytes/reader.go
new file mode 100644
index 0000000000000000000000000000000000000000..d4c3066e0620d058c5648b72bf8322cb6b169594
--- /dev/null
+++ b/go/src/bytes/reader.go
@@ -0,0 +1,159 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bytes
+
+import (
+ "errors"
+ "io"
+ "unicode/utf8"
+)
+
+// A Reader implements the [io.Reader], [io.ReaderAt], [io.WriterTo], [io.Seeker],
+// [io.ByteScanner], and [io.RuneScanner] interfaces by reading from
+// a byte slice.
+// Unlike a [Buffer], a Reader is read-only and supports seeking.
+// The zero value for Reader operates like a Reader of an empty slice.
+type Reader struct {
+ s []byte
+ i int64 // current reading index
+ prevRune int // index of previous rune; or < 0
+}
+
+// Len returns the number of bytes of the unread portion of the
+// slice.
+func (r *Reader) Len() int {
+ if r.i >= int64(len(r.s)) {
+ return 0
+ }
+ return int(int64(len(r.s)) - r.i)
+}
+
+// Size returns the original length of the underlying byte slice.
+// Size is the number of bytes available for reading via [Reader.ReadAt].
+// The result is unaffected by any method calls except [Reader.Reset].
+func (r *Reader) Size() int64 { return int64(len(r.s)) }
+
+// Read implements the [io.Reader] interface.
+func (r *Reader) Read(b []byte) (n int, err error) {
+ if r.i >= int64(len(r.s)) {
+ return 0, io.EOF
+ }
+ r.prevRune = -1
+ n = copy(b, r.s[r.i:])
+ r.i += int64(n)
+ return
+}
+
+// ReadAt implements the [io.ReaderAt] interface.
+func (r *Reader) ReadAt(b []byte, off int64) (n int, err error) {
+ // cannot modify state - see io.ReaderAt
+ if off < 0 {
+ return 0, errors.New("bytes.Reader.ReadAt: negative offset")
+ }
+ if off >= int64(len(r.s)) {
+ return 0, io.EOF
+ }
+ n = copy(b, r.s[off:])
+ if n < len(b) {
+ err = io.EOF
+ }
+ return
+}
+
+// ReadByte implements the [io.ByteReader] interface.
+func (r *Reader) ReadByte() (byte, error) {
+ r.prevRune = -1
+ if r.i >= int64(len(r.s)) {
+ return 0, io.EOF
+ }
+ b := r.s[r.i]
+ r.i++
+ return b, nil
+}
+
+// UnreadByte complements [Reader.ReadByte] in implementing the [io.ByteScanner] interface.
+func (r *Reader) UnreadByte() error {
+ if r.i <= 0 {
+ return errors.New("bytes.Reader.UnreadByte: at beginning of slice")
+ }
+ r.prevRune = -1
+ r.i--
+ return nil
+}
+
+// ReadRune implements the [io.RuneReader] interface.
+func (r *Reader) ReadRune() (ch rune, size int, err error) {
+ if r.i >= int64(len(r.s)) {
+ r.prevRune = -1
+ return 0, 0, io.EOF
+ }
+ r.prevRune = int(r.i)
+ if c := r.s[r.i]; c < utf8.RuneSelf {
+ r.i++
+ return rune(c), 1, nil
+ }
+ ch, size = utf8.DecodeRune(r.s[r.i:])
+ r.i += int64(size)
+ return
+}
+
+// UnreadRune complements [Reader.ReadRune] in implementing the [io.RuneScanner] interface.
+func (r *Reader) UnreadRune() error {
+ if r.i <= 0 {
+ return errors.New("bytes.Reader.UnreadRune: at beginning of slice")
+ }
+ if r.prevRune < 0 {
+ return errors.New("bytes.Reader.UnreadRune: previous operation was not ReadRune")
+ }
+ r.i = int64(r.prevRune)
+ r.prevRune = -1
+ return nil
+}
+
+// Seek implements the [io.Seeker] interface.
+func (r *Reader) Seek(offset int64, whence int) (int64, error) {
+ r.prevRune = -1
+ var abs int64
+ switch whence {
+ case io.SeekStart:
+ abs = offset
+ case io.SeekCurrent:
+ abs = r.i + offset
+ case io.SeekEnd:
+ abs = int64(len(r.s)) + offset
+ default:
+ return 0, errors.New("bytes.Reader.Seek: invalid whence")
+ }
+ if abs < 0 {
+ return 0, errors.New("bytes.Reader.Seek: negative position")
+ }
+ r.i = abs
+ return abs, nil
+}
+
+// WriteTo implements the [io.WriterTo] interface.
+func (r *Reader) WriteTo(w io.Writer) (n int64, err error) {
+ r.prevRune = -1
+ if r.i >= int64(len(r.s)) {
+ return 0, nil
+ }
+ b := r.s[r.i:]
+ m, err := w.Write(b)
+ if m > len(b) {
+ panic("bytes.Reader.WriteTo: invalid Write count")
+ }
+ r.i += int64(m)
+ n = int64(m)
+ if m != len(b) && err == nil {
+ err = io.ErrShortWrite
+ }
+ return
+}
+
+// Reset resets the [Reader] to be reading from b.
+func (r *Reader) Reset(b []byte) { *r = Reader{b, 0, -1} }
+
+// NewReader returns a new [Reader] reading from b.
+func NewReader(b []byte) *Reader { return &Reader{b, 0, -1} }
diff --git a/go/src/bytes/reader_test.go b/go/src/bytes/reader_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..9119c944ace4783ebb9fb3295beb7be23336e009
--- /dev/null
+++ b/go/src/bytes/reader_test.go
@@ -0,0 +1,319 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bytes_test
+
+import (
+ . "bytes"
+ "fmt"
+ "io"
+ "sync"
+ "testing"
+)
+
+func TestReader(t *testing.T) {
+ r := NewReader([]byte("0123456789"))
+ tests := []struct {
+ off int64
+ seek int
+ n int
+ want string
+ wantpos int64
+ readerr error
+ seekerr string
+ }{
+ {seek: io.SeekStart, off: 0, n: 20, want: "0123456789"},
+ {seek: io.SeekStart, off: 1, n: 1, want: "1"},
+ {seek: io.SeekCurrent, off: 1, wantpos: 3, n: 2, want: "34"},
+ {seek: io.SeekStart, off: -1, seekerr: "bytes.Reader.Seek: negative position"},
+ {seek: io.SeekStart, off: 1 << 33, wantpos: 1 << 33, readerr: io.EOF},
+ {seek: io.SeekCurrent, off: 1, wantpos: 1<<33 + 1, readerr: io.EOF},
+ {seek: io.SeekStart, n: 5, want: "01234"},
+ {seek: io.SeekCurrent, n: 5, want: "56789"},
+ {seek: io.SeekEnd, off: -1, n: 1, wantpos: 9, want: "9"},
+ }
+
+ for i, tt := range tests {
+ pos, err := r.Seek(tt.off, tt.seek)
+ if err == nil && tt.seekerr != "" {
+ t.Errorf("%d. want seek error %q", i, tt.seekerr)
+ continue
+ }
+ if err != nil && err.Error() != tt.seekerr {
+ t.Errorf("%d. seek error = %q; want %q", i, err.Error(), tt.seekerr)
+ continue
+ }
+ if tt.wantpos != 0 && tt.wantpos != pos {
+ t.Errorf("%d. pos = %d, want %d", i, pos, tt.wantpos)
+ }
+ buf := make([]byte, tt.n)
+ n, err := r.Read(buf)
+ if err != tt.readerr {
+ t.Errorf("%d. read = %v; want %v", i, err, tt.readerr)
+ continue
+ }
+ got := string(buf[:n])
+ if got != tt.want {
+ t.Errorf("%d. got %q; want %q", i, got, tt.want)
+ }
+ }
+}
+
+func TestReadAfterBigSeek(t *testing.T) {
+ r := NewReader([]byte("0123456789"))
+ if _, err := r.Seek(1<<31+5, io.SeekStart); err != nil {
+ t.Fatal(err)
+ }
+ if n, err := r.Read(make([]byte, 10)); n != 0 || err != io.EOF {
+ t.Errorf("Read = %d, %v; want 0, EOF", n, err)
+ }
+}
+
+func TestReaderAt(t *testing.T) {
+ r := NewReader([]byte("0123456789"))
+ tests := []struct {
+ off int64
+ n int
+ want string
+ wanterr any
+ }{
+ {0, 10, "0123456789", nil},
+ {1, 10, "123456789", io.EOF},
+ {1, 9, "123456789", nil},
+ {11, 10, "", io.EOF},
+ {0, 0, "", nil},
+ {-1, 0, "", "bytes.Reader.ReadAt: negative offset"},
+ }
+ for i, tt := range tests {
+ b := make([]byte, tt.n)
+ rn, err := r.ReadAt(b, tt.off)
+ got := string(b[:rn])
+ if got != tt.want {
+ t.Errorf("%d. got %q; want %q", i, got, tt.want)
+ }
+ if fmt.Sprintf("%v", err) != fmt.Sprintf("%v", tt.wanterr) {
+ t.Errorf("%d. got error = %v; want %v", i, err, tt.wanterr)
+ }
+ }
+}
+
+func TestReaderAtConcurrent(t *testing.T) {
+ // Test for the race detector, to verify ReadAt doesn't mutate
+ // any state.
+ r := NewReader([]byte("0123456789"))
+ var wg sync.WaitGroup
+ for i := 0; i < 5; i++ {
+ wg.Add(1)
+ go func(i int) {
+ defer wg.Done()
+ var buf [1]byte
+ r.ReadAt(buf[:], int64(i))
+ }(i)
+ }
+ wg.Wait()
+}
+
+func TestEmptyReaderConcurrent(t *testing.T) {
+ // Test for the race detector, to verify a Read that doesn't yield any bytes
+ // is okay to use from multiple goroutines. This was our historic behavior.
+ // See golang.org/issue/7856
+ r := NewReader([]byte{})
+ var wg sync.WaitGroup
+ for i := 0; i < 5; i++ {
+ wg.Add(2)
+ go func() {
+ defer wg.Done()
+ var buf [1]byte
+ r.Read(buf[:])
+ }()
+ go func() {
+ defer wg.Done()
+ r.Read(nil)
+ }()
+ }
+ wg.Wait()
+}
+
+func TestReaderWriteTo(t *testing.T) {
+ for i := 0; i < 30; i += 3 {
+ var l int
+ if i > 0 {
+ l = len(testString) / i
+ }
+ s := testString[:l]
+ r := NewReader(testBytes[:l])
+ var b Buffer
+ n, err := r.WriteTo(&b)
+ if expect := int64(len(s)); n != expect {
+ t.Errorf("got %v; want %v", n, expect)
+ }
+ if err != nil {
+ t.Errorf("for length %d: got error = %v; want nil", l, err)
+ }
+ if b.String() != s {
+ t.Errorf("got string %q; want %q", b.String(), s)
+ }
+ if r.Len() != 0 {
+ t.Errorf("reader contains %v bytes; want 0", r.Len())
+ }
+ }
+}
+
+func TestReaderLen(t *testing.T) {
+ const data = "hello world"
+ r := NewReader([]byte(data))
+ if got, want := r.Len(), 11; got != want {
+ t.Errorf("r.Len(): got %d, want %d", got, want)
+ }
+ if n, err := r.Read(make([]byte, 10)); err != nil || n != 10 {
+ t.Errorf("Read failed: read %d %v", n, err)
+ }
+ if got, want := r.Len(), 1; got != want {
+ t.Errorf("r.Len(): got %d, want %d", got, want)
+ }
+ if n, err := r.Read(make([]byte, 1)); err != nil || n != 1 {
+ t.Errorf("Read failed: read %d %v; want 1, nil", n, err)
+ }
+ if got, want := r.Len(), 0; got != want {
+ t.Errorf("r.Len(): got %d, want %d", got, want)
+ }
+}
+
+var UnreadRuneErrorTests = []struct {
+ name string
+ f func(*Reader)
+}{
+ {"Read", func(r *Reader) { r.Read([]byte{0}) }},
+ {"ReadByte", func(r *Reader) { r.ReadByte() }},
+ {"UnreadRune", func(r *Reader) { r.UnreadRune() }},
+ {"Seek", func(r *Reader) { r.Seek(0, io.SeekCurrent) }},
+ {"WriteTo", func(r *Reader) { r.WriteTo(&Buffer{}) }},
+}
+
+func TestUnreadRuneError(t *testing.T) {
+ for _, tt := range UnreadRuneErrorTests {
+ reader := NewReader([]byte("0123456789"))
+ if _, _, err := reader.ReadRune(); err != nil {
+ // should not happen
+ t.Fatal(err)
+ }
+ tt.f(reader)
+ err := reader.UnreadRune()
+ if err == nil {
+ t.Errorf("Unreading after %s: expected error", tt.name)
+ }
+ }
+}
+
+func TestReaderDoubleUnreadRune(t *testing.T) {
+ buf := NewBuffer([]byte("groucho"))
+ if _, _, err := buf.ReadRune(); err != nil {
+ // should not happen
+ t.Fatal(err)
+ }
+ if err := buf.UnreadByte(); err != nil {
+ // should not happen
+ t.Fatal(err)
+ }
+ if err := buf.UnreadByte(); err == nil {
+ t.Fatal("UnreadByte: expected error, got nil")
+ }
+}
+
+// verify that copying from an empty reader always has the same results,
+// regardless of the presence of a WriteTo method.
+func TestReaderCopyNothing(t *testing.T) {
+ type nErr struct {
+ n int64
+ err error
+ }
+ type justReader struct {
+ io.Reader
+ }
+ type justWriter struct {
+ io.Writer
+ }
+ discard := justWriter{io.Discard} // hide ReadFrom
+
+ var with, withOut nErr
+ with.n, with.err = io.Copy(discard, NewReader(nil))
+ withOut.n, withOut.err = io.Copy(discard, justReader{NewReader(nil)})
+ if with != withOut {
+ t.Errorf("behavior differs: with = %#v; without: %#v", with, withOut)
+ }
+}
+
+// tests that Len is affected by reads, but Size is not.
+func TestReaderLenSize(t *testing.T) {
+ r := NewReader([]byte("abc"))
+ io.CopyN(io.Discard, r, 1)
+ if r.Len() != 2 {
+ t.Errorf("Len = %d; want 2", r.Len())
+ }
+ if r.Size() != 3 {
+ t.Errorf("Size = %d; want 3", r.Size())
+ }
+}
+
+func TestReaderReset(t *testing.T) {
+ r := NewReader([]byte("世界"))
+ if _, _, err := r.ReadRune(); err != nil {
+ t.Errorf("ReadRune: unexpected error: %v", err)
+ }
+
+ const want = "abcdef"
+ r.Reset([]byte(want))
+ if err := r.UnreadRune(); err == nil {
+ t.Errorf("UnreadRune: expected error, got nil")
+ }
+ buf, err := io.ReadAll(r)
+ if err != nil {
+ t.Errorf("ReadAll: unexpected error: %v", err)
+ }
+ if got := string(buf); got != want {
+ t.Errorf("ReadAll: got %q, want %q", got, want)
+ }
+}
+
+func TestReaderZero(t *testing.T) {
+ if l := (&Reader{}).Len(); l != 0 {
+ t.Errorf("Len: got %d, want 0", l)
+ }
+
+ if n, err := (&Reader{}).Read(nil); n != 0 || err != io.EOF {
+ t.Errorf("Read: got %d, %v; want 0, io.EOF", n, err)
+ }
+
+ if n, err := (&Reader{}).ReadAt(nil, 11); n != 0 || err != io.EOF {
+ t.Errorf("ReadAt: got %d, %v; want 0, io.EOF", n, err)
+ }
+
+ if b, err := (&Reader{}).ReadByte(); b != 0 || err != io.EOF {
+ t.Errorf("ReadByte: got %d, %v; want 0, io.EOF", b, err)
+ }
+
+ if ch, size, err := (&Reader{}).ReadRune(); ch != 0 || size != 0 || err != io.EOF {
+ t.Errorf("ReadRune: got %d, %d, %v; want 0, 0, io.EOF", ch, size, err)
+ }
+
+ if offset, err := (&Reader{}).Seek(11, io.SeekStart); offset != 11 || err != nil {
+ t.Errorf("Seek: got %d, %v; want 11, nil", offset, err)
+ }
+
+ if s := (&Reader{}).Size(); s != 0 {
+ t.Errorf("Size: got %d, want 0", s)
+ }
+
+ if (&Reader{}).UnreadByte() == nil {
+ t.Errorf("UnreadByte: got nil, want error")
+ }
+
+ if (&Reader{}).UnreadRune() == nil {
+ t.Errorf("UnreadRune: got nil, want error")
+ }
+
+ if n, err := (&Reader{}).WriteTo(io.Discard); n != 0 || err != nil {
+ t.Errorf("WriteTo: got %d, %v; want 0, nil", n, err)
+ }
+}
diff --git a/go/src/cmd/README.vendor b/go/src/cmd/README.vendor
new file mode 100644
index 0000000000000000000000000000000000000000..ac0df5e9257124ba06492f523eeed3706041fa1c
--- /dev/null
+++ b/go/src/cmd/README.vendor
@@ -0,0 +1,2 @@
+See src/README.vendor for information on loading vendored packages
+and updating the vendor directory.
diff --git a/go/src/cmd/go.mod b/go/src/cmd/go.mod
new file mode 100644
index 0000000000000000000000000000000000000000..14107c2d8ed9f306480bdfaf63ac45cd2349ab7d
--- /dev/null
+++ b/go/src/cmd/go.mod
@@ -0,0 +1,21 @@
+module cmd
+
+go 1.26
+
+require (
+ github.com/google/pprof v0.0.0-20251114195745-4902fdda35c8
+ golang.org/x/arch v0.23.0
+ golang.org/x/build v0.0.0-20251128064159-b9bfd88b30e8
+ golang.org/x/mod v0.30.1-0.20251115032019-269c237cf350
+ golang.org/x/sync v0.19.0
+ golang.org/x/sys v0.39.0
+ golang.org/x/telemetry v0.0.0-20251128220624-abf20d0e57ec
+ golang.org/x/term v0.38.0
+ golang.org/x/tools v0.39.1-0.20260323181443-4f499ecaa91d
+)
+
+require (
+ github.com/ianlancetaylor/demangle v0.0.0-20250417193237-f615e6bd150b // indirect
+ golang.org/x/text v0.32.0 // indirect
+ rsc.io/markdown v0.0.0-20240306144322-0bf8f97ee8ef // indirect
+)
diff --git a/go/src/cmd/go.sum b/go/src/cmd/go.sum
new file mode 100644
index 0000000000000000000000000000000000000000..c4920417b21b3ddad34b7f663e997680c578315f
--- /dev/null
+++ b/go/src/cmd/go.sum
@@ -0,0 +1,28 @@
+github.com/google/go-cmp v0.7.0 h1:wk8382ETsv4JYUZwIsn6YpYiWiBsYLSJiTsyBybVuN8=
+github.com/google/go-cmp v0.7.0/go.mod h1:pXiqmnSA92OHEEa9HXL2W4E7lf9JzCmGVUdgjX3N/iU=
+github.com/google/pprof v0.0.0-20251114195745-4902fdda35c8 h1:3DsUAV+VNEQa2CUVLxCY3f87278uWfIDhJnbdvDjvmE=
+github.com/google/pprof v0.0.0-20251114195745-4902fdda35c8/go.mod h1:I6V7YzU0XDpsHqbsyrghnFZLO1gwK6NPTNvmetQIk9U=
+github.com/ianlancetaylor/demangle v0.0.0-20250417193237-f615e6bd150b h1:ogbOPx86mIhFy764gGkqnkFC8m5PJA7sPzlk9ppLVQA=
+github.com/ianlancetaylor/demangle v0.0.0-20250417193237-f615e6bd150b/go.mod h1:gx7rwoVhcfuVKG5uya9Hs3Sxj7EIvldVofAWIUtGouw=
+github.com/yuin/goldmark v1.6.0 h1:boZcn2GTjpsynOsC0iJHnBWa4Bi0qzfJjthwauItG68=
+github.com/yuin/goldmark v1.6.0/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
+golang.org/x/arch v0.23.0 h1:lKF64A2jF6Zd8L0knGltUnegD62JMFBiCPBmQpToHhg=
+golang.org/x/arch v0.23.0/go.mod h1:dNHoOeKiyja7GTvF9NJS1l3Z2yntpQNzgrjh1cU103A=
+golang.org/x/build v0.0.0-20251128064159-b9bfd88b30e8 h1:Mp+uRtHbKFW85lGBTOkOOfkPBz7AUKmZGcflkavmGRM=
+golang.org/x/build v0.0.0-20251128064159-b9bfd88b30e8/go.mod h1:Jx2RBBeTWGRSCwfSZ+w2Hg1f7LjWycsSkx+EciLAmPE=
+golang.org/x/mod v0.30.1-0.20251115032019-269c237cf350 h1:JGDMsCp8NahDR9HSvwrF6V8tzEf87m7Bo4oZ07vRxdU=
+golang.org/x/mod v0.30.1-0.20251115032019-269c237cf350/go.mod h1:lAsf5O2EvJeSFMiBxXDki7sCgAxEUcZHXoXMKT4GJKc=
+golang.org/x/sync v0.19.0 h1:vV+1eWNmZ5geRlYjzm2adRgW2/mcpevXNg50YZtPCE4=
+golang.org/x/sync v0.19.0/go.mod h1:9KTHXmSnoGruLpwFjVSX0lNNA75CykiMECbovNTZqGI=
+golang.org/x/sys v0.39.0 h1:CvCKL8MeisomCi6qNZ+wbb0DN9E5AATixKsvNtMoMFk=
+golang.org/x/sys v0.39.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
+golang.org/x/telemetry v0.0.0-20251128220624-abf20d0e57ec h1:dRVkWZl6bUOp+oxnOe4BuyhWSIPmt29N4ooHarm7Ic8=
+golang.org/x/telemetry v0.0.0-20251128220624-abf20d0e57ec/go.mod h1:hKdjCMrbv9skySur+Nek8Hd0uJ0GuxJIoIX2payrIdQ=
+golang.org/x/term v0.38.0 h1:PQ5pkm/rLO6HnxFR7N2lJHOZX6Kez5Y1gDSJla6jo7Q=
+golang.org/x/term v0.38.0/go.mod h1:bSEAKrOT1W+VSu9TSCMtoGEOUcKxOKgl3LE5QEF/xVg=
+golang.org/x/text v0.32.0 h1:ZD01bjUt1FQ9WJ0ClOL5vxgxOI/sVCNgX1YtKwcY0mU=
+golang.org/x/text v0.32.0/go.mod h1:o/rUWzghvpD5TXrTIBuJU77MTaN0ljMWE47kxGJQ7jY=
+golang.org/x/tools v0.39.1-0.20260323181443-4f499ecaa91d h1:d9RYG/Z8xQk+tFy5IyhSwUrt4HhSsqHw/uhwmn1KaJg=
+golang.org/x/tools v0.39.1-0.20260323181443-4f499ecaa91d/go.mod h1:JnefbkDPyD8UU2kI5fuf8ZX4/yUeh9W877ZeBONxUqQ=
+rsc.io/markdown v0.0.0-20240306144322-0bf8f97ee8ef h1:mqLYrXCXYEZOop9/Dbo6RPX11539nwiCNBb1icVPmw8=
+rsc.io/markdown v0.0.0-20240306144322-0bf8f97ee8ef/go.mod h1:8xcPgWmwlZONN1D9bjxtHEjrUtSEa3fakVF8iaewYKQ=
diff --git a/go/src/cmp/cmp.go b/go/src/cmp/cmp.go
new file mode 100644
index 0000000000000000000000000000000000000000..a13834c39858924ba9f1b4b57051124b8f3dc8bb
--- /dev/null
+++ b/go/src/cmp/cmp.go
@@ -0,0 +1,77 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package cmp provides types and functions related to comparing
+// ordered values.
+package cmp
+
+// Ordered is a constraint that permits any ordered type: any type
+// that supports the operators < <= >= >.
+// If future releases of Go add new ordered types,
+// this constraint will be modified to include them.
+//
+// Note that floating-point types may contain NaN ("not-a-number") values.
+// An operator such as == or < will always report false when
+// comparing a NaN value with any other value, NaN or not.
+// See the [Compare] function for a consistent way to compare NaN values.
+type Ordered interface {
+ ~int | ~int8 | ~int16 | ~int32 | ~int64 |
+ ~uint | ~uint8 | ~uint16 | ~uint32 | ~uint64 | ~uintptr |
+ ~float32 | ~float64 |
+ ~string
+}
+
+// Less reports whether x is less than y.
+// For floating-point types, a NaN is considered less than any non-NaN,
+// and -0.0 is not less than (is equal to) 0.0.
+func Less[T Ordered](x, y T) bool {
+ return (isNaN(x) && !isNaN(y)) || x < y
+}
+
+// Compare returns
+//
+// -1 if x is less than y,
+// 0 if x equals y,
+// +1 if x is greater than y.
+//
+// For floating-point types, a NaN is considered less than any non-NaN,
+// a NaN is considered equal to a NaN, and -0.0 is equal to 0.0.
+func Compare[T Ordered](x, y T) int {
+ xNaN := isNaN(x)
+ yNaN := isNaN(y)
+ if xNaN {
+ if yNaN {
+ return 0
+ }
+ return -1
+ }
+ if yNaN {
+ return +1
+ }
+ if x < y {
+ return -1
+ }
+ if x > y {
+ return +1
+ }
+ return 0
+}
+
+// isNaN reports whether x is a NaN without requiring the math package.
+// This will always return false if T is not floating-point.
+func isNaN[T Ordered](x T) bool {
+ return x != x
+}
+
+// Or returns the first of its arguments that is not equal to the zero value.
+// If no argument is non-zero, it returns the zero value.
+func Or[T comparable](vals ...T) T {
+ var zero T
+ for _, val := range vals {
+ if val != zero {
+ return val
+ }
+ }
+ return zero
+}
diff --git a/go/src/cmp/cmp_test.go b/go/src/cmp/cmp_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..c9816cba11665739ed079de1d07570af01df0e9f
--- /dev/null
+++ b/go/src/cmp/cmp_test.go
@@ -0,0 +1,202 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cmp_test
+
+import (
+ "cmp"
+ "fmt"
+ "math"
+ "slices"
+ "sort"
+ "strings"
+ "testing"
+ "unsafe"
+)
+
+var negzero = math.Copysign(0, -1)
+var nonnilptr uintptr = uintptr(unsafe.Pointer(&negzero))
+var nilptr uintptr = uintptr(unsafe.Pointer(nil))
+
+var tests = []struct {
+ x, y any
+ compare int
+}{
+ {1, 2, -1},
+ {1, 1, 0},
+ {2, 1, +1},
+ {"a", "aa", -1},
+ {"a", "a", 0},
+ {"aa", "a", +1},
+ {1.0, 1.1, -1},
+ {1.1, 1.1, 0},
+ {1.1, 1.0, +1},
+ {math.Inf(1), math.Inf(1), 0},
+ {math.Inf(-1), math.Inf(-1), 0},
+ {math.Inf(-1), 1.0, -1},
+ {1.0, math.Inf(-1), +1},
+ {math.Inf(1), 1.0, +1},
+ {1.0, math.Inf(1), -1},
+ {math.NaN(), math.NaN(), 0},
+ {0.0, math.NaN(), +1},
+ {math.NaN(), 0.0, -1},
+ {math.NaN(), math.Inf(-1), -1},
+ {math.Inf(-1), math.NaN(), +1},
+ {0.0, 0.0, 0},
+ {negzero, negzero, 0},
+ {negzero, 0.0, 0},
+ {0.0, negzero, 0},
+ {negzero, 1.0, -1},
+ {negzero, -1.0, +1},
+ {nilptr, nonnilptr, -1},
+ {nonnilptr, nilptr, 1},
+ {nonnilptr, nonnilptr, 0},
+}
+
+func TestLess(t *testing.T) {
+ for _, test := range tests {
+ var b bool
+ switch test.x.(type) {
+ case int:
+ b = cmp.Less(test.x.(int), test.y.(int))
+ case string:
+ b = cmp.Less(test.x.(string), test.y.(string))
+ case float64:
+ b = cmp.Less(test.x.(float64), test.y.(float64))
+ case uintptr:
+ b = cmp.Less(test.x.(uintptr), test.y.(uintptr))
+ }
+ if b != (test.compare < 0) {
+ t.Errorf("Less(%v, %v) == %t, want %t", test.x, test.y, b, test.compare < 0)
+ }
+ }
+}
+
+func TestCompare(t *testing.T) {
+ for _, test := range tests {
+ var c int
+ switch test.x.(type) {
+ case int:
+ c = cmp.Compare(test.x.(int), test.y.(int))
+ case string:
+ c = cmp.Compare(test.x.(string), test.y.(string))
+ case float64:
+ c = cmp.Compare(test.x.(float64), test.y.(float64))
+ case uintptr:
+ c = cmp.Compare(test.x.(uintptr), test.y.(uintptr))
+ }
+ if c != test.compare {
+ t.Errorf("Compare(%v, %v) == %d, want %d", test.x, test.y, c, test.compare)
+ }
+ }
+}
+
+func TestSort(t *testing.T) {
+ // Test that our comparison function is consistent with
+ // sort.Float64s.
+ input := []float64{1.0, 0.0, negzero, math.Inf(1), math.Inf(-1), math.NaN()}
+ sort.Float64s(input)
+ for i := 0; i < len(input)-1; i++ {
+ if cmp.Less(input[i+1], input[i]) {
+ t.Errorf("Less sort mismatch at %d in %v", i, input)
+ }
+ if cmp.Compare(input[i], input[i+1]) > 0 {
+ t.Errorf("Compare sort mismatch at %d in %v", i, input)
+ }
+ }
+}
+
+func TestOr(t *testing.T) {
+ cases := []struct {
+ in []int
+ want int
+ }{
+ {nil, 0},
+ {[]int{0}, 0},
+ {[]int{1}, 1},
+ {[]int{0, 2}, 2},
+ {[]int{3, 0}, 3},
+ {[]int{4, 5}, 4},
+ {[]int{0, 6, 7}, 6},
+ }
+ for _, tc := range cases {
+ if got := cmp.Or(tc.in...); got != tc.want {
+ t.Errorf("cmp.Or(%v) = %v; want %v", tc.in, got, tc.want)
+ }
+ }
+}
+
+func ExampleOr() {
+ // Suppose we have some user input
+ // that may or may not be an empty string
+ userInput1 := ""
+ userInput2 := "some text"
+
+ fmt.Println(cmp.Or(userInput1, "default"))
+ fmt.Println(cmp.Or(userInput2, "default"))
+ fmt.Println(cmp.Or(userInput1, userInput2, "default"))
+ // Output:
+ // default
+ // some text
+ // some text
+}
+
+func ExampleOr_sort() {
+ type Order struct {
+ Product string
+ Customer string
+ Price float64
+ }
+ orders := []Order{
+ {"foo", "alice", 1.00},
+ {"bar", "bob", 3.00},
+ {"baz", "carol", 4.00},
+ {"foo", "alice", 2.00},
+ {"bar", "carol", 1.00},
+ {"foo", "bob", 4.00},
+ }
+ // Sort by customer first, product second, and last by higher price
+ slices.SortFunc(orders, func(a, b Order) int {
+ return cmp.Or(
+ strings.Compare(a.Customer, b.Customer),
+ strings.Compare(a.Product, b.Product),
+ cmp.Compare(b.Price, a.Price),
+ )
+ })
+ for _, order := range orders {
+ fmt.Printf("%s %s %.2f\n", order.Product, order.Customer, order.Price)
+ }
+
+ // Output:
+ // foo alice 2.00
+ // foo alice 1.00
+ // bar bob 3.00
+ // foo bob 4.00
+ // bar carol 1.00
+ // baz carol 4.00
+}
+
+func ExampleLess() {
+ fmt.Println(cmp.Less(1, 2))
+ fmt.Println(cmp.Less("a", "aa"))
+ fmt.Println(cmp.Less(1.0, math.NaN()))
+ fmt.Println(cmp.Less(math.NaN(), 1.0))
+ // Output:
+ // true
+ // true
+ // false
+ // true
+}
+
+func ExampleCompare() {
+ fmt.Println(cmp.Compare(1, 2))
+ fmt.Println(cmp.Compare("a", "aa"))
+ fmt.Println(cmp.Compare(1.5, 1.5))
+ fmt.Println(cmp.Compare(math.NaN(), 1.0))
+ // Output:
+ // -1
+ // -1
+ // 0
+ // -1
+}
diff --git a/go/src/context/afterfunc_test.go b/go/src/context/afterfunc_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..c2ef1062d3851fd055f27009bd1eb613d049619a
--- /dev/null
+++ b/go/src/context/afterfunc_test.go
@@ -0,0 +1,141 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package context_test
+
+import (
+ "context"
+ "sync"
+ "testing"
+ "time"
+)
+
+// afterFuncContext is a context that's not one of the types
+// defined in context.go, that supports registering AfterFuncs.
+type afterFuncContext struct {
+ mu sync.Mutex
+ afterFuncs map[*byte]func()
+ done chan struct{}
+ err error
+}
+
+var _ context.Context = (*afterFuncContext)(nil)
+
+func (c *afterFuncContext) Deadline() (time.Time, bool) {
+ return time.Time{}, false
+}
+
+func (c *afterFuncContext) Done() <-chan struct{} {
+ c.mu.Lock()
+ defer c.mu.Unlock()
+ if c.done == nil {
+ c.done = make(chan struct{})
+ }
+ return c.done
+}
+
+func (c *afterFuncContext) Err() error {
+ c.mu.Lock()
+ defer c.mu.Unlock()
+ return c.err
+}
+
+func (c *afterFuncContext) Value(key any) any {
+ return nil
+}
+
+func (c *afterFuncContext) AfterFunc(f func()) func() bool {
+ c.mu.Lock()
+ defer c.mu.Unlock()
+ k := new(byte)
+ if c.afterFuncs == nil {
+ c.afterFuncs = make(map[*byte]func())
+ }
+ c.afterFuncs[k] = f
+ return func() bool {
+ c.mu.Lock()
+ defer c.mu.Unlock()
+ _, ok := c.afterFuncs[k]
+ delete(c.afterFuncs, k)
+ return ok
+ }
+}
+
+func (c *afterFuncContext) cancel(err error) {
+ c.mu.Lock()
+ defer c.mu.Unlock()
+ if c.err != nil {
+ return
+ }
+ c.err = err
+ for _, f := range c.afterFuncs {
+ go f()
+ }
+ c.afterFuncs = nil
+}
+
+func TestCustomContextAfterFuncCancel(t *testing.T) {
+ ctx0 := &afterFuncContext{}
+ ctx1, cancel := context.WithCancel(ctx0)
+ defer cancel()
+ ctx0.cancel(context.Canceled)
+ <-ctx1.Done()
+}
+
+func TestCustomContextAfterFuncTimeout(t *testing.T) {
+ ctx0 := &afterFuncContext{}
+ ctx1, cancel := context.WithTimeout(ctx0, veryLongDuration)
+ defer cancel()
+ ctx0.cancel(context.Canceled)
+ <-ctx1.Done()
+}
+
+func TestCustomContextAfterFuncAfterFunc(t *testing.T) {
+ ctx0 := &afterFuncContext{}
+ donec := make(chan struct{})
+ stop := context.AfterFunc(ctx0, func() {
+ close(donec)
+ })
+ defer stop()
+ ctx0.cancel(context.Canceled)
+ <-donec
+}
+
+func TestCustomContextAfterFuncUnregisterCancel(t *testing.T) {
+ ctx0 := &afterFuncContext{}
+ _, cancel1 := context.WithCancel(ctx0)
+ _, cancel2 := context.WithCancel(ctx0)
+ if got, want := len(ctx0.afterFuncs), 2; got != want {
+ t.Errorf("after WithCancel(ctx0): ctx0 has %v afterFuncs, want %v", got, want)
+ }
+ cancel1()
+ cancel2()
+ if got, want := len(ctx0.afterFuncs), 0; got != want {
+ t.Errorf("after canceling WithCancel(ctx0): ctx0 has %v afterFuncs, want %v", got, want)
+ }
+}
+
+func TestCustomContextAfterFuncUnregisterTimeout(t *testing.T) {
+ ctx0 := &afterFuncContext{}
+ _, cancel := context.WithTimeout(ctx0, veryLongDuration)
+ if got, want := len(ctx0.afterFuncs), 1; got != want {
+ t.Errorf("after WithTimeout(ctx0, d): ctx0 has %v afterFuncs, want %v", got, want)
+ }
+ cancel()
+ if got, want := len(ctx0.afterFuncs), 0; got != want {
+ t.Errorf("after canceling WithTimeout(ctx0, d): ctx0 has %v afterFuncs, want %v", got, want)
+ }
+}
+
+func TestCustomContextAfterFuncUnregisterAfterFunc(t *testing.T) {
+ ctx0 := &afterFuncContext{}
+ stop := context.AfterFunc(ctx0, func() {})
+ if got, want := len(ctx0.afterFuncs), 1; got != want {
+ t.Errorf("after AfterFunc(ctx0, f): ctx0 has %v afterFuncs, want %v", got, want)
+ }
+ stop()
+ if got, want := len(ctx0.afterFuncs), 0; got != want {
+ t.Errorf("after stopping AfterFunc(ctx0, f): ctx0 has %v afterFuncs, want %v", got, want)
+ }
+}
diff --git a/go/src/context/benchmark_test.go b/go/src/context/benchmark_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..d10950d258970f203bc2aec8def4096fca89fdbf
--- /dev/null
+++ b/go/src/context/benchmark_test.go
@@ -0,0 +1,210 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package context_test
+
+import (
+ . "context"
+ "fmt"
+ "runtime"
+ "sync"
+ "testing"
+ "time"
+)
+
+func BenchmarkCommonParentCancel(b *testing.B) {
+ root := WithValue(Background(), "key", "value")
+ shared, sharedcancel := WithCancel(root)
+ defer sharedcancel()
+
+ b.ResetTimer()
+ b.RunParallel(func(pb *testing.PB) {
+ x := 0
+ for pb.Next() {
+ ctx, cancel := WithCancel(shared)
+ if ctx.Value("key").(string) != "value" {
+ b.Fatal("should not be reached")
+ }
+ for i := 0; i < 100; i++ {
+ x /= x + 1
+ }
+ cancel()
+ for i := 0; i < 100; i++ {
+ x /= x + 1
+ }
+ }
+ })
+}
+
+func BenchmarkWithTimeout(b *testing.B) {
+ for concurrency := 40; concurrency <= 4e5; concurrency *= 100 {
+ name := fmt.Sprintf("concurrency=%d", concurrency)
+ b.Run(name, func(b *testing.B) {
+ benchmarkWithTimeout(b, concurrency)
+ })
+ }
+}
+
+func benchmarkWithTimeout(b *testing.B, concurrentContexts int) {
+ gomaxprocs := runtime.GOMAXPROCS(0)
+ perPContexts := concurrentContexts / gomaxprocs
+ root := Background()
+
+ // Generate concurrent contexts.
+ var wg sync.WaitGroup
+ ccf := make([][]CancelFunc, gomaxprocs)
+ for i := range ccf {
+ wg.Add(1)
+ go func(i int) {
+ defer wg.Done()
+ cf := make([]CancelFunc, perPContexts)
+ for j := range cf {
+ _, cf[j] = WithTimeout(root, time.Hour)
+ }
+ ccf[i] = cf
+ }(i)
+ }
+ wg.Wait()
+
+ b.ResetTimer()
+ b.RunParallel(func(pb *testing.PB) {
+ wcf := make([]CancelFunc, 10)
+ for pb.Next() {
+ for i := range wcf {
+ _, wcf[i] = WithTimeout(root, time.Hour)
+ }
+ for _, f := range wcf {
+ f()
+ }
+ }
+ })
+ b.StopTimer()
+
+ for _, cf := range ccf {
+ for _, f := range cf {
+ f()
+ }
+ }
+}
+
+func BenchmarkCancelTree(b *testing.B) {
+ depths := []int{1, 10, 100, 1000}
+ for _, d := range depths {
+ b.Run(fmt.Sprintf("depth=%d", d), func(b *testing.B) {
+ b.Run("Root=Background", func(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ buildContextTree(Background(), d)
+ }
+ })
+ b.Run("Root=OpenCanceler", func(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ ctx, cancel := WithCancel(Background())
+ buildContextTree(ctx, d)
+ cancel()
+ }
+ })
+ b.Run("Root=ClosedCanceler", func(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ ctx, cancel := WithCancel(Background())
+ cancel()
+ buildContextTree(ctx, d)
+ }
+ })
+ })
+ }
+}
+
+func buildContextTree(root Context, depth int) {
+ for d := 0; d < depth; d++ {
+ root, _ = WithCancel(root)
+ }
+}
+
+func BenchmarkCheckCanceled(b *testing.B) {
+ ctx, cancel := WithCancel(Background())
+ cancel()
+ b.Run("Err", func(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ ctx.Err()
+ }
+ })
+ b.Run("Done", func(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ select {
+ case <-ctx.Done():
+ default:
+ }
+ }
+ })
+}
+
+func BenchmarkContextCancelDone(b *testing.B) {
+ ctx, cancel := WithCancel(Background())
+ defer cancel()
+
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ select {
+ case <-ctx.Done():
+ default:
+ }
+ }
+ })
+}
+
+func BenchmarkDeepValueNewGoRoutine(b *testing.B) {
+ for _, depth := range []int{10, 20, 30, 50, 100} {
+ ctx := Background()
+ for i := 0; i < depth; i++ {
+ ctx = WithValue(ctx, i, i)
+ }
+
+ b.Run(fmt.Sprintf("depth=%d", depth), func(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ var wg sync.WaitGroup
+ wg.Add(1)
+ go func() {
+ defer wg.Done()
+ ctx.Value(-1)
+ }()
+ wg.Wait()
+ }
+ })
+ }
+}
+
+func BenchmarkDeepValueSameGoRoutine(b *testing.B) {
+ for _, depth := range []int{10, 20, 30, 50, 100} {
+ ctx := Background()
+ for i := 0; i < depth; i++ {
+ ctx = WithValue(ctx, i, i)
+ }
+
+ b.Run(fmt.Sprintf("depth=%d", depth), func(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ ctx.Value(-1)
+ }
+ })
+ }
+}
+
+func BenchmarkErrOK(b *testing.B) {
+ ctx, cancel := WithCancel(Background())
+ defer cancel()
+ for b.Loop() {
+ if err := ctx.Err(); err != nil {
+ b.Fatalf("ctx.Err() = %v", err)
+ }
+ }
+}
+
+func BenchmarkErrCanceled(b *testing.B) {
+ ctx, cancel := WithCancel(Background())
+ cancel()
+ for b.Loop() {
+ if err := ctx.Err(); err == nil {
+ b.Fatalf("ctx.Err() = %v", err)
+ }
+ }
+}
diff --git a/go/src/context/context.go b/go/src/context/context.go
new file mode 100644
index 0000000000000000000000000000000000000000..d00ac67e38296573d20520dbd7aceb2fd1a52906
--- /dev/null
+++ b/go/src/context/context.go
@@ -0,0 +1,806 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package context defines the Context type, which carries deadlines,
+// cancellation signals, and other request-scoped values across API boundaries
+// and between processes.
+//
+// Incoming requests to a server should create a [Context], and outgoing
+// calls to servers should accept a Context. The chain of function
+// calls between them must propagate the Context, optionally replacing
+// it with a derived Context created using [WithCancel], [WithDeadline],
+// [WithTimeout], or [WithValue].
+//
+// A Context may be canceled to indicate that work done on its behalf should stop.
+// A Context with a deadline is canceled after the deadline passes.
+// When a Context is canceled, all Contexts derived from it are also canceled.
+//
+// The [WithCancel], [WithDeadline], and [WithTimeout] functions take a
+// Context (the parent) and return a derived Context (the child) and a
+// [CancelFunc]. Calling the CancelFunc directly cancels the child and its
+// children, removes the parent's reference to the child, and stops
+// any associated timers. Failing to call the CancelFunc leaks the
+// child and its children until the parent is canceled. The go vet tool
+// checks that CancelFuncs are used on all control-flow paths.
+//
+// The [WithCancelCause], [WithDeadlineCause], and [WithTimeoutCause] functions
+// return a [CancelCauseFunc], which takes an error and records it as
+// the cancellation cause. Calling [Cause] on the canceled context
+// or any of its children retrieves the cause. If no cause is specified,
+// Cause(ctx) returns the same value as ctx.Err().
+//
+// Programs that use Contexts should follow these rules to keep interfaces
+// consistent across packages and enable static analysis tools to check context
+// propagation:
+//
+// Do not store Contexts inside a struct type; instead, pass a Context
+// explicitly to each function that needs it. This is discussed further in
+// https://go.dev/blog/context-and-structs. The Context should be the first
+// parameter, typically named ctx:
+//
+// func DoSomething(ctx context.Context, arg Arg) error {
+// // ... use ctx ...
+// }
+//
+// Do not pass a nil [Context], even if a function permits it. Pass [context.TODO]
+// if you are unsure about which Context to use.
+//
+// Use context Values only for request-scoped data that transits processes and
+// APIs, not for passing optional parameters to functions.
+//
+// The same Context may be passed to functions running in different goroutines;
+// Contexts are safe for simultaneous use by multiple goroutines.
+//
+// See https://go.dev/blog/context for example code for a server that uses
+// Contexts.
+package context
+
+import (
+ "errors"
+ "internal/reflectlite"
+ "sync"
+ "sync/atomic"
+ "time"
+)
+
+// A Context carries a deadline, a cancellation signal, and other values across
+// API boundaries.
+//
+// Context's methods may be called by multiple goroutines simultaneously.
+type Context interface {
+ // Deadline returns the time when work done on behalf of this context
+ // should be canceled. Deadline returns ok==false when no deadline is
+ // set. Successive calls to Deadline return the same results.
+ Deadline() (deadline time.Time, ok bool)
+
+ // Done returns a channel that's closed when work done on behalf of this
+ // context should be canceled. Done may return nil if this context can
+ // never be canceled. Successive calls to Done return the same value.
+ // The close of the Done channel may happen asynchronously,
+ // after the cancel function returns.
+ //
+ // WithCancel arranges for Done to be closed when cancel is called;
+ // WithDeadline arranges for Done to be closed when the deadline
+ // expires; WithTimeout arranges for Done to be closed when the timeout
+ // elapses.
+ //
+ // Done is provided for use in select statements:
+ //
+ // // Stream generates values with DoSomething and sends them to out
+ // // until DoSomething returns an error or ctx.Done is closed.
+ // func Stream(ctx context.Context, out chan<- Value) error {
+ // for {
+ // v, err := DoSomething(ctx)
+ // if err != nil {
+ // return err
+ // }
+ // select {
+ // case <-ctx.Done():
+ // return ctx.Err()
+ // case out <- v:
+ // }
+ // }
+ // }
+ //
+ // See https://go.dev/blog/pipelines for more examples of how to use
+ // a Done channel for cancellation.
+ Done() <-chan struct{}
+
+ // If Done is not yet closed, Err returns nil.
+ // If Done is closed, Err returns a non-nil error explaining why:
+ // DeadlineExceeded if the context's deadline passed,
+ // or Canceled if the context was canceled for some other reason.
+ // After Err returns a non-nil error, successive calls to Err return the same error.
+ Err() error
+
+ // Value returns the value associated with this context for key, or nil
+ // if no value is associated with key. Successive calls to Value with
+ // the same key returns the same result.
+ //
+ // Use context values only for request-scoped data that transits
+ // processes and API boundaries, not for passing optional parameters to
+ // functions.
+ //
+ // A key identifies a specific value in a Context. Functions that wish
+ // to store values in Context typically allocate a key in a global
+ // variable then use that key as the argument to context.WithValue and
+ // Context.Value. A key can be any type that supports equality;
+ // packages should define keys as an unexported type to avoid
+ // collisions.
+ //
+ // Packages that define a Context key should provide type-safe accessors
+ // for the values stored using that key:
+ //
+ // // Package user defines a User type that's stored in Contexts.
+ // package user
+ //
+ // import "context"
+ //
+ // // User is the type of value stored in the Contexts.
+ // type User struct {...}
+ //
+ // // key is an unexported type for keys defined in this package.
+ // // This prevents collisions with keys defined in other packages.
+ // type key int
+ //
+ // // userKey is the key for user.User values in Contexts. It is
+ // // unexported; clients use user.NewContext and user.FromContext
+ // // instead of using this key directly.
+ // var userKey key
+ //
+ // // NewContext returns a new Context that carries value u.
+ // func NewContext(ctx context.Context, u *User) context.Context {
+ // return context.WithValue(ctx, userKey, u)
+ // }
+ //
+ // // FromContext returns the User value stored in ctx, if any.
+ // func FromContext(ctx context.Context) (*User, bool) {
+ // u, ok := ctx.Value(userKey).(*User)
+ // return u, ok
+ // }
+ Value(key any) any
+}
+
+// Canceled is the error returned by [Context.Err] when the context is canceled
+// for some reason other than its deadline passing.
+var Canceled = errors.New("context canceled")
+
+// DeadlineExceeded is the error returned by [Context.Err] when the context is canceled
+// due to its deadline passing.
+var DeadlineExceeded error = deadlineExceededError{}
+
+type deadlineExceededError struct{}
+
+func (deadlineExceededError) Error() string { return "context deadline exceeded" }
+func (deadlineExceededError) Timeout() bool { return true }
+func (deadlineExceededError) Temporary() bool { return true }
+
+// An emptyCtx is never canceled, has no values, and has no deadline.
+// It is the common base of backgroundCtx and todoCtx.
+type emptyCtx struct{}
+
+func (emptyCtx) Deadline() (deadline time.Time, ok bool) {
+ return
+}
+
+func (emptyCtx) Done() <-chan struct{} {
+ return nil
+}
+
+func (emptyCtx) Err() error {
+ return nil
+}
+
+func (emptyCtx) Value(key any) any {
+ return nil
+}
+
+type backgroundCtx struct{ emptyCtx }
+
+func (backgroundCtx) String() string {
+ return "context.Background"
+}
+
+type todoCtx struct{ emptyCtx }
+
+func (todoCtx) String() string {
+ return "context.TODO"
+}
+
+// Background returns a non-nil, empty [Context]. It is never canceled, has no
+// values, and has no deadline. It is typically used by the main function,
+// initialization, and tests, and as the top-level Context for incoming
+// requests.
+func Background() Context {
+ return backgroundCtx{}
+}
+
+// TODO returns a non-nil, empty [Context]. Code should use context.TODO when
+// it's unclear which Context to use or it is not yet available (because the
+// surrounding function has not yet been extended to accept a Context
+// parameter).
+func TODO() Context {
+ return todoCtx{}
+}
+
+// A CancelFunc tells an operation to abandon its work.
+// A CancelFunc does not wait for the work to stop.
+// A CancelFunc may be called by multiple goroutines simultaneously.
+// After the first call, subsequent calls to a CancelFunc do nothing.
+type CancelFunc func()
+
+// WithCancel returns a derived context that points to the parent context
+// but has a new Done channel. The returned context's Done channel is closed
+// when the returned cancel function is called or when the parent context's
+// Done channel is closed, whichever happens first.
+//
+// Canceling this context releases resources associated with it, so code should
+// call cancel as soon as the operations running in this [Context] complete.
+func WithCancel(parent Context) (ctx Context, cancel CancelFunc) {
+ c := withCancel(parent)
+ return c, func() { c.cancel(true, Canceled, nil) }
+}
+
+// A CancelCauseFunc behaves like a [CancelFunc] but additionally sets the cancellation cause.
+// This cause can be retrieved by calling [Cause] on the canceled Context or on
+// any of its derived Contexts.
+//
+// If the context has already been canceled, CancelCauseFunc does not set the cause.
+// For example, if childContext is derived from parentContext:
+// - if parentContext is canceled with cause1 before childContext is canceled with cause2,
+// then Cause(parentContext) == Cause(childContext) == cause1
+// - if childContext is canceled with cause2 before parentContext is canceled with cause1,
+// then Cause(parentContext) == cause1 and Cause(childContext) == cause2
+type CancelCauseFunc func(cause error)
+
+// WithCancelCause behaves like [WithCancel] but returns a [CancelCauseFunc] instead of a [CancelFunc].
+// Calling cancel with a non-nil error (the "cause") records that error in ctx;
+// it can then be retrieved using Cause(ctx).
+// Calling cancel with nil sets the cause to Canceled.
+//
+// Example use:
+//
+// ctx, cancel := context.WithCancelCause(parent)
+// cancel(myError)
+// ctx.Err() // returns context.Canceled
+// context.Cause(ctx) // returns myError
+func WithCancelCause(parent Context) (ctx Context, cancel CancelCauseFunc) {
+ c := withCancel(parent)
+ return c, func(cause error) { c.cancel(true, Canceled, cause) }
+}
+
+func withCancel(parent Context) *cancelCtx {
+ if parent == nil {
+ panic("cannot create context from nil parent")
+ }
+ c := &cancelCtx{}
+ c.propagateCancel(parent, c)
+ return c
+}
+
+// Cause returns a non-nil error explaining why c was canceled.
+// The first cancellation of c or one of its parents sets the cause.
+// If that cancellation happened via a call to CancelCauseFunc(err),
+// then [Cause] returns err.
+// Otherwise Cause(c) returns the same value as c.Err().
+// Cause returns nil if c has not been canceled yet.
+func Cause(c Context) error {
+ err := c.Err()
+ if err == nil {
+ return nil
+ }
+ if cc, ok := c.Value(&cancelCtxKey).(*cancelCtx); ok {
+ cc.mu.Lock()
+ cause := cc.cause
+ cc.mu.Unlock()
+ if cause != nil {
+ return cause
+ }
+ // The parent cancelCtx doesn't have a cause,
+ // so c must have been canceled in some custom context implementation.
+ }
+ // We don't have a cause to return from a parent cancelCtx,
+ // so return the context's error.
+ return err
+}
+
+// AfterFunc arranges to call f in its own goroutine after ctx is canceled.
+// If ctx is already canceled, AfterFunc calls f immediately in its own goroutine.
+//
+// Multiple calls to AfterFunc on a context operate independently;
+// one does not replace another.
+//
+// Calling the returned stop function stops the association of ctx with f.
+// It returns true if the call stopped f from being run.
+// If stop returns false,
+// either the context is canceled and f has been started in its own goroutine;
+// or f was already stopped.
+// The stop function does not wait for f to complete before returning.
+// If the caller needs to know whether f is completed,
+// it must coordinate with f explicitly.
+//
+// If ctx has a "AfterFunc(func()) func() bool" method,
+// AfterFunc will use it to schedule the call.
+func AfterFunc(ctx Context, f func()) (stop func() bool) {
+ a := &afterFuncCtx{
+ f: f,
+ }
+ a.cancelCtx.propagateCancel(ctx, a)
+ return func() bool {
+ stopped := false
+ a.once.Do(func() {
+ stopped = true
+ })
+ if stopped {
+ a.cancel(true, Canceled, nil)
+ }
+ return stopped
+ }
+}
+
+type afterFuncer interface {
+ AfterFunc(func()) func() bool
+}
+
+type afterFuncCtx struct {
+ cancelCtx
+ once sync.Once // either starts running f or stops f from running
+ f func()
+}
+
+func (a *afterFuncCtx) cancel(removeFromParent bool, err, cause error) {
+ a.cancelCtx.cancel(false, err, cause)
+ if removeFromParent {
+ removeChild(a.Context, a)
+ }
+ a.once.Do(func() {
+ go a.f()
+ })
+}
+
+// A stopCtx is used as the parent context of a cancelCtx when
+// an AfterFunc has been registered with the parent.
+// It holds the stop function used to unregister the AfterFunc.
+type stopCtx struct {
+ Context
+ stop func() bool
+}
+
+// goroutines counts the number of goroutines ever created; for testing.
+var goroutines atomic.Int32
+
+// &cancelCtxKey is the key that a cancelCtx returns itself for.
+var cancelCtxKey int
+
+// parentCancelCtx returns the underlying *cancelCtx for parent.
+// It does this by looking up parent.Value(&cancelCtxKey) to find
+// the innermost enclosing *cancelCtx and then checking whether
+// parent.Done() matches that *cancelCtx. (If not, the *cancelCtx
+// has been wrapped in a custom implementation providing a
+// different done channel, in which case we should not bypass it.)
+func parentCancelCtx(parent Context) (*cancelCtx, bool) {
+ done := parent.Done()
+ if done == closedchan || done == nil {
+ return nil, false
+ }
+ p, ok := parent.Value(&cancelCtxKey).(*cancelCtx)
+ if !ok {
+ return nil, false
+ }
+ pdone, _ := p.done.Load().(chan struct{})
+ if pdone != done {
+ return nil, false
+ }
+ return p, true
+}
+
+// removeChild removes a context from its parent.
+func removeChild(parent Context, child canceler) {
+ if s, ok := parent.(stopCtx); ok {
+ s.stop()
+ return
+ }
+ p, ok := parentCancelCtx(parent)
+ if !ok {
+ return
+ }
+ p.mu.Lock()
+ if p.children != nil {
+ delete(p.children, child)
+ }
+ p.mu.Unlock()
+}
+
+// A canceler is a context type that can be canceled directly. The
+// implementations are *cancelCtx and *timerCtx.
+type canceler interface {
+ cancel(removeFromParent bool, err, cause error)
+ Done() <-chan struct{}
+}
+
+// closedchan is a reusable closed channel.
+var closedchan = make(chan struct{})
+
+func init() {
+ close(closedchan)
+}
+
+// A cancelCtx can be canceled. When canceled, it also cancels any children
+// that implement canceler.
+type cancelCtx struct {
+ Context
+
+ mu sync.Mutex // protects following fields
+ done atomic.Value // of chan struct{}, created lazily, closed by first cancel call
+ children map[canceler]struct{} // set to nil by the first cancel call
+ err atomic.Value // set to non-nil by the first cancel call
+ cause error // set to non-nil by the first cancel call
+}
+
+func (c *cancelCtx) Value(key any) any {
+ if key == &cancelCtxKey {
+ return c
+ }
+ return value(c.Context, key)
+}
+
+func (c *cancelCtx) Done() <-chan struct{} {
+ d := c.done.Load()
+ if d != nil {
+ return d.(chan struct{})
+ }
+ c.mu.Lock()
+ defer c.mu.Unlock()
+ d = c.done.Load()
+ if d == nil {
+ d = make(chan struct{})
+ c.done.Store(d)
+ }
+ return d.(chan struct{})
+}
+
+func (c *cancelCtx) Err() error {
+ // An atomic load is ~5x faster than a mutex, which can matter in tight loops.
+ if err := c.err.Load(); err != nil {
+ // Ensure the done channel has been closed before returning a non-nil error.
+ <-c.Done()
+ return err.(error)
+ }
+ return nil
+}
+
+// propagateCancel arranges for child to be canceled when parent is.
+// It sets the parent context of cancelCtx.
+func (c *cancelCtx) propagateCancel(parent Context, child canceler) {
+ c.Context = parent
+
+ done := parent.Done()
+ if done == nil {
+ return // parent is never canceled
+ }
+
+ select {
+ case <-done:
+ // parent is already canceled
+ child.cancel(false, parent.Err(), Cause(parent))
+ return
+ default:
+ }
+
+ if p, ok := parentCancelCtx(parent); ok {
+ // parent is a *cancelCtx, or derives from one.
+ p.mu.Lock()
+ if err := p.err.Load(); err != nil {
+ // parent has already been canceled
+ child.cancel(false, err.(error), p.cause)
+ } else {
+ if p.children == nil {
+ p.children = make(map[canceler]struct{})
+ }
+ p.children[child] = struct{}{}
+ }
+ p.mu.Unlock()
+ return
+ }
+
+ if a, ok := parent.(afterFuncer); ok {
+ // parent implements an AfterFunc method.
+ c.mu.Lock()
+ stop := a.AfterFunc(func() {
+ child.cancel(false, parent.Err(), Cause(parent))
+ })
+ c.Context = stopCtx{
+ Context: parent,
+ stop: stop,
+ }
+ c.mu.Unlock()
+ return
+ }
+
+ goroutines.Add(1)
+ go func() {
+ select {
+ case <-parent.Done():
+ child.cancel(false, parent.Err(), Cause(parent))
+ case <-child.Done():
+ }
+ }()
+}
+
+type stringer interface {
+ String() string
+}
+
+func contextName(c Context) string {
+ if s, ok := c.(stringer); ok {
+ return s.String()
+ }
+ return reflectlite.TypeOf(c).String()
+}
+
+func (c *cancelCtx) String() string {
+ return contextName(c.Context) + ".WithCancel"
+}
+
+// cancel closes c.done, cancels each of c's children, and, if
+// removeFromParent is true, removes c from its parent's children.
+// cancel sets c.cause to cause if this is the first time c is canceled.
+func (c *cancelCtx) cancel(removeFromParent bool, err, cause error) {
+ if err == nil {
+ panic("context: internal error: missing cancel error")
+ }
+ if cause == nil {
+ cause = err
+ }
+ c.mu.Lock()
+ if c.err.Load() != nil {
+ c.mu.Unlock()
+ return // already canceled
+ }
+ c.err.Store(err)
+ c.cause = cause
+ d, _ := c.done.Load().(chan struct{})
+ if d == nil {
+ c.done.Store(closedchan)
+ } else {
+ close(d)
+ }
+ for child := range c.children {
+ // NOTE: acquiring the child's lock while holding parent's lock.
+ child.cancel(false, err, cause)
+ }
+ c.children = nil
+ c.mu.Unlock()
+
+ if removeFromParent {
+ removeChild(c.Context, c)
+ }
+}
+
+// WithoutCancel returns a derived context that points to the parent context
+// and is not canceled when parent is canceled.
+// The returned context returns no Deadline or Err, and its Done channel is nil.
+// Calling [Cause] on the returned context returns nil.
+func WithoutCancel(parent Context) Context {
+ if parent == nil {
+ panic("cannot create context from nil parent")
+ }
+ return withoutCancelCtx{parent}
+}
+
+type withoutCancelCtx struct {
+ c Context
+}
+
+func (withoutCancelCtx) Deadline() (deadline time.Time, ok bool) {
+ return
+}
+
+func (withoutCancelCtx) Done() <-chan struct{} {
+ return nil
+}
+
+func (withoutCancelCtx) Err() error {
+ return nil
+}
+
+func (c withoutCancelCtx) Value(key any) any {
+ return value(c, key)
+}
+
+func (c withoutCancelCtx) String() string {
+ return contextName(c.c) + ".WithoutCancel"
+}
+
+// WithDeadline returns a derived context that points to the parent context
+// but has the deadline adjusted to be no later than d. If the parent's
+// deadline is already earlier than d, WithDeadline(parent, d) is semantically
+// equivalent to parent. The returned [Context.Done] channel is closed when
+// the deadline expires, when the returned cancel function is called,
+// or when the parent context's Done channel is closed, whichever happens first.
+//
+// Canceling this context releases resources associated with it, so code should
+// call cancel as soon as the operations running in this [Context] complete.
+func WithDeadline(parent Context, d time.Time) (Context, CancelFunc) {
+ return WithDeadlineCause(parent, d, nil)
+}
+
+// WithDeadlineCause behaves like [WithDeadline] but also sets the cause of the
+// returned Context when the deadline is exceeded. The returned [CancelFunc] does
+// not set the cause.
+func WithDeadlineCause(parent Context, d time.Time, cause error) (Context, CancelFunc) {
+ if parent == nil {
+ panic("cannot create context from nil parent")
+ }
+ if cur, ok := parent.Deadline(); ok && cur.Before(d) {
+ // The current deadline is already sooner than the new one.
+ return WithCancel(parent)
+ }
+ c := &timerCtx{
+ deadline: d,
+ }
+ c.cancelCtx.propagateCancel(parent, c)
+ dur := time.Until(d)
+ if dur <= 0 {
+ c.cancel(true, DeadlineExceeded, cause) // deadline has already passed
+ return c, func() { c.cancel(false, Canceled, nil) }
+ }
+ c.mu.Lock()
+ defer c.mu.Unlock()
+ if c.err.Load() == nil {
+ c.timer = time.AfterFunc(dur, func() {
+ c.cancel(true, DeadlineExceeded, cause)
+ })
+ }
+ return c, func() { c.cancel(true, Canceled, nil) }
+}
+
+// A timerCtx carries a timer and a deadline. It embeds a cancelCtx to
+// implement Done and Err. It implements cancel by stopping its timer then
+// delegating to cancelCtx.cancel.
+type timerCtx struct {
+ cancelCtx
+ timer *time.Timer // Under cancelCtx.mu.
+
+ deadline time.Time
+}
+
+func (c *timerCtx) Deadline() (deadline time.Time, ok bool) {
+ return c.deadline, true
+}
+
+func (c *timerCtx) String() string {
+ return contextName(c.cancelCtx.Context) + ".WithDeadline(" +
+ c.deadline.String() + " [" +
+ time.Until(c.deadline).String() + "])"
+}
+
+func (c *timerCtx) cancel(removeFromParent bool, err, cause error) {
+ c.cancelCtx.cancel(false, err, cause)
+ if removeFromParent {
+ // Remove this timerCtx from its parent cancelCtx's children.
+ removeChild(c.cancelCtx.Context, c)
+ }
+ c.mu.Lock()
+ if c.timer != nil {
+ c.timer.Stop()
+ c.timer = nil
+ }
+ c.mu.Unlock()
+}
+
+// WithTimeout returns WithDeadline(parent, time.Now().Add(timeout)).
+//
+// Canceling this context releases resources associated with it, so code should
+// call cancel as soon as the operations running in this [Context] complete:
+//
+// func slowOperationWithTimeout(ctx context.Context) (Result, error) {
+// ctx, cancel := context.WithTimeout(ctx, 100*time.Millisecond)
+// defer cancel() // releases resources if slowOperation completes before timeout elapses
+// return slowOperation(ctx)
+// }
+func WithTimeout(parent Context, timeout time.Duration) (Context, CancelFunc) {
+ return WithDeadline(parent, time.Now().Add(timeout))
+}
+
+// WithTimeoutCause behaves like [WithTimeout] but also sets the cause of the
+// returned Context when the timeout expires. The returned [CancelFunc] does
+// not set the cause.
+func WithTimeoutCause(parent Context, timeout time.Duration, cause error) (Context, CancelFunc) {
+ return WithDeadlineCause(parent, time.Now().Add(timeout), cause)
+}
+
+// WithValue returns a derived context that points to the parent Context.
+// In the derived context, the value associated with key is val.
+//
+// Use context Values only for request-scoped data that transits processes and
+// APIs, not for passing optional parameters to functions.
+//
+// The provided key must be comparable and should not be of type
+// string or any other built-in type to avoid collisions between
+// packages using context. Users of WithValue should define their own
+// types for keys. To avoid allocating when assigning to an
+// interface{}, context keys often have concrete type
+// struct{}. Alternatively, exported context key variables' static
+// type should be a pointer or interface.
+func WithValue(parent Context, key, val any) Context {
+ if parent == nil {
+ panic("cannot create context from nil parent")
+ }
+ if key == nil {
+ panic("nil key")
+ }
+ if !reflectlite.TypeOf(key).Comparable() {
+ panic("key is not comparable")
+ }
+ return &valueCtx{parent, key, val}
+}
+
+// A valueCtx carries a key-value pair. It implements Value for that key and
+// delegates all other calls to the embedded Context.
+type valueCtx struct {
+ Context
+ key, val any
+}
+
+// stringify tries a bit to stringify v, without using fmt, since we don't
+// want context depending on the unicode tables. This is only used by
+// *valueCtx.String().
+func stringify(v any) string {
+ switch s := v.(type) {
+ case stringer:
+ return s.String()
+ case string:
+ return s
+ case nil:
+ return ""
+ }
+ return reflectlite.TypeOf(v).String()
+}
+
+func (c *valueCtx) String() string {
+ return contextName(c.Context) + ".WithValue(" +
+ stringify(c.key) + ", " +
+ stringify(c.val) + ")"
+}
+
+func (c *valueCtx) Value(key any) any {
+ if c.key == key {
+ return c.val
+ }
+ return value(c.Context, key)
+}
+
+func value(c Context, key any) any {
+ for {
+ switch ctx := c.(type) {
+ case *valueCtx:
+ if key == ctx.key {
+ return ctx.val
+ }
+ c = ctx.Context
+ case *cancelCtx:
+ if key == &cancelCtxKey {
+ return c
+ }
+ c = ctx.Context
+ case withoutCancelCtx:
+ if key == &cancelCtxKey {
+ // This implements Cause(ctx) == nil
+ // when ctx is created using WithoutCancel.
+ return nil
+ }
+ c = ctx.c
+ case *timerCtx:
+ if key == &cancelCtxKey {
+ return &ctx.cancelCtx
+ }
+ c = ctx.Context
+ case backgroundCtx, todoCtx:
+ return nil
+ default:
+ return c.Value(key)
+ }
+ }
+}
diff --git a/go/src/context/context_test.go b/go/src/context/context_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..ad47f853dd4b3620df67b12dcc554524546d9a74
--- /dev/null
+++ b/go/src/context/context_test.go
@@ -0,0 +1,297 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package context
+
+// Tests in package context cannot depend directly on package testing due to an import cycle.
+// If your test requires access to unexported members of the context package,
+// add your test below as `func XTestFoo(t testingT)` and add a `TestFoo` to x_test.go
+// that calls it. Otherwise, write a regular test in a test.go file in package context_test.
+
+import (
+ "time"
+)
+
+type testingT interface {
+ Deadline() (time.Time, bool)
+ Error(args ...any)
+ Errorf(format string, args ...any)
+ Fail()
+ FailNow()
+ Failed() bool
+ Fatal(args ...any)
+ Fatalf(format string, args ...any)
+ Helper()
+ Log(args ...any)
+ Logf(format string, args ...any)
+ Name() string
+ Parallel()
+ Skip(args ...any)
+ SkipNow()
+ Skipf(format string, args ...any)
+ Skipped() bool
+}
+
+const veryLongDuration = 1000 * time.Hour // an arbitrary upper bound on the test's running time
+
+func contains(m map[canceler]struct{}, key canceler) bool {
+ _, ret := m[key]
+ return ret
+}
+
+func XTestParentFinishesChild(t testingT) {
+ // Context tree:
+ // parent -> cancelChild
+ // parent -> valueChild -> timerChild
+ // parent -> afterChild
+ parent, cancel := WithCancel(Background())
+ cancelChild, stop := WithCancel(parent)
+ defer stop()
+ valueChild := WithValue(parent, "key", "value")
+ timerChild, stop := WithTimeout(valueChild, veryLongDuration)
+ defer stop()
+ afterStop := AfterFunc(parent, func() {})
+ defer afterStop()
+
+ select {
+ case x := <-parent.Done():
+ t.Errorf("<-parent.Done() == %v want nothing (it should block)", x)
+ case x := <-cancelChild.Done():
+ t.Errorf("<-cancelChild.Done() == %v want nothing (it should block)", x)
+ case x := <-timerChild.Done():
+ t.Errorf("<-timerChild.Done() == %v want nothing (it should block)", x)
+ case x := <-valueChild.Done():
+ t.Errorf("<-valueChild.Done() == %v want nothing (it should block)", x)
+ default:
+ }
+
+ // The parent's children should contain the three cancelable children.
+ pc := parent.(*cancelCtx)
+ cc := cancelChild.(*cancelCtx)
+ tc := timerChild.(*timerCtx)
+ pc.mu.Lock()
+ var ac *afterFuncCtx
+ for c := range pc.children {
+ if a, ok := c.(*afterFuncCtx); ok {
+ ac = a
+ break
+ }
+ }
+ if len(pc.children) != 3 || !contains(pc.children, cc) || !contains(pc.children, tc) || ac == nil {
+ t.Errorf("bad linkage: pc.children = %v, want %v, %v, and an afterFunc",
+ pc.children, cc, tc)
+ }
+ pc.mu.Unlock()
+
+ if p, ok := parentCancelCtx(cc.Context); !ok || p != pc {
+ t.Errorf("bad linkage: parentCancelCtx(cancelChild.Context) = %v, %v want %v, true", p, ok, pc)
+ }
+ if p, ok := parentCancelCtx(tc.Context); !ok || p != pc {
+ t.Errorf("bad linkage: parentCancelCtx(timerChild.Context) = %v, %v want %v, true", p, ok, pc)
+ }
+ if p, ok := parentCancelCtx(ac.Context); !ok || p != pc {
+ t.Errorf("bad linkage: parentCancelCtx(afterChild.Context) = %v, %v want %v, true", p, ok, pc)
+ }
+
+ cancel()
+
+ pc.mu.Lock()
+ if len(pc.children) != 0 {
+ t.Errorf("pc.cancel didn't clear pc.children = %v", pc.children)
+ }
+ pc.mu.Unlock()
+
+ // parent and children should all be finished.
+ check := func(ctx Context, name string) {
+ select {
+ case <-ctx.Done():
+ default:
+ t.Errorf("<-%s.Done() blocked, but shouldn't have", name)
+ }
+ if e := ctx.Err(); e != Canceled {
+ t.Errorf("%s.Err() == %v want %v", name, e, Canceled)
+ }
+ }
+ check(parent, "parent")
+ check(cancelChild, "cancelChild")
+ check(valueChild, "valueChild")
+ check(timerChild, "timerChild")
+
+ // WithCancel should return a canceled context on a canceled parent.
+ precanceledChild := WithValue(parent, "key", "value")
+ select {
+ case <-precanceledChild.Done():
+ default:
+ t.Errorf("<-precanceledChild.Done() blocked, but shouldn't have")
+ }
+ if e := precanceledChild.Err(); e != Canceled {
+ t.Errorf("precanceledChild.Err() == %v want %v", e, Canceled)
+ }
+}
+
+func XTestChildFinishesFirst(t testingT) {
+ cancelable, stop := WithCancel(Background())
+ defer stop()
+ for _, parent := range []Context{Background(), cancelable} {
+ child, cancel := WithCancel(parent)
+
+ select {
+ case x := <-parent.Done():
+ t.Errorf("<-parent.Done() == %v want nothing (it should block)", x)
+ case x := <-child.Done():
+ t.Errorf("<-child.Done() == %v want nothing (it should block)", x)
+ default:
+ }
+
+ cc := child.(*cancelCtx)
+ pc, pcok := parent.(*cancelCtx) // pcok == false when parent == Background()
+ if p, ok := parentCancelCtx(cc.Context); ok != pcok || (ok && pc != p) {
+ t.Errorf("bad linkage: parentCancelCtx(cc.Context) = %v, %v want %v, %v", p, ok, pc, pcok)
+ }
+
+ if pcok {
+ pc.mu.Lock()
+ if len(pc.children) != 1 || !contains(pc.children, cc) {
+ t.Errorf("bad linkage: pc.children = %v, cc = %v", pc.children, cc)
+ }
+ pc.mu.Unlock()
+ }
+
+ cancel()
+
+ if pcok {
+ pc.mu.Lock()
+ if len(pc.children) != 0 {
+ t.Errorf("child's cancel didn't remove self from pc.children = %v", pc.children)
+ }
+ pc.mu.Unlock()
+ }
+
+ // child should be finished.
+ select {
+ case <-child.Done():
+ default:
+ t.Errorf("<-child.Done() blocked, but shouldn't have")
+ }
+ if e := child.Err(); e != Canceled {
+ t.Errorf("child.Err() == %v want %v", e, Canceled)
+ }
+
+ // parent should not be finished.
+ select {
+ case x := <-parent.Done():
+ t.Errorf("<-parent.Done() == %v want nothing (it should block)", x)
+ default:
+ }
+ if e := parent.Err(); e != nil {
+ t.Errorf("parent.Err() == %v want nil", e)
+ }
+ }
+}
+
+func XTestCancelRemoves(t testingT) {
+ checkChildren := func(when string, ctx Context, want int) {
+ if got := len(ctx.(*cancelCtx).children); got != want {
+ t.Errorf("%s: context has %d children, want %d", when, got, want)
+ }
+ }
+
+ ctx, _ := WithCancel(Background())
+ checkChildren("after creation", ctx, 0)
+ _, cancel := WithCancel(ctx)
+ checkChildren("with WithCancel child ", ctx, 1)
+ cancel()
+ checkChildren("after canceling WithCancel child", ctx, 0)
+
+ ctx, _ = WithCancel(Background())
+ checkChildren("after creation", ctx, 0)
+ _, cancel = WithTimeout(ctx, 60*time.Minute)
+ checkChildren("with WithTimeout child ", ctx, 1)
+ cancel()
+ checkChildren("after canceling WithTimeout child", ctx, 0)
+
+ ctx, _ = WithCancel(Background())
+ checkChildren("after creation", ctx, 0)
+ stop := AfterFunc(ctx, func() {})
+ checkChildren("with AfterFunc child ", ctx, 1)
+ stop()
+ checkChildren("after stopping AfterFunc child ", ctx, 0)
+}
+
+type myCtx struct {
+ Context
+}
+
+type myDoneCtx struct {
+ Context
+}
+
+func (d *myDoneCtx) Done() <-chan struct{} {
+ c := make(chan struct{})
+ return c
+}
+func XTestCustomContextGoroutines(t testingT) {
+ g := goroutines.Load()
+ checkNoGoroutine := func() {
+ t.Helper()
+ now := goroutines.Load()
+ if now != g {
+ t.Fatalf("%d goroutines created", now-g)
+ }
+ }
+ checkCreatedGoroutine := func() {
+ t.Helper()
+ now := goroutines.Load()
+ if now != g+1 {
+ t.Fatalf("%d goroutines created, want 1", now-g)
+ }
+ g = now
+ }
+
+ _, cancel0 := WithCancel(&myDoneCtx{Background()})
+ cancel0()
+ checkCreatedGoroutine()
+
+ _, cancel0 = WithTimeout(&myDoneCtx{Background()}, veryLongDuration)
+ cancel0()
+ checkCreatedGoroutine()
+
+ checkNoGoroutine()
+ defer checkNoGoroutine()
+
+ ctx1, cancel1 := WithCancel(Background())
+ defer cancel1()
+ checkNoGoroutine()
+
+ ctx2 := &myCtx{ctx1}
+ ctx3, cancel3 := WithCancel(ctx2)
+ defer cancel3()
+ checkNoGoroutine()
+
+ _, cancel3b := WithCancel(&myDoneCtx{ctx2})
+ defer cancel3b()
+ checkCreatedGoroutine() // ctx1 is not providing Done, must not be used
+
+ ctx4, cancel4 := WithTimeout(ctx3, veryLongDuration)
+ defer cancel4()
+ checkNoGoroutine()
+
+ ctx5, cancel5 := WithCancel(ctx4)
+ defer cancel5()
+ checkNoGoroutine()
+
+ cancel5()
+ checkNoGoroutine()
+
+ _, cancel6 := WithTimeout(ctx5, veryLongDuration)
+ defer cancel6()
+ checkNoGoroutine()
+
+ // Check applied to canceled context.
+ cancel6()
+ cancel1()
+ _, cancel7 := WithCancel(ctx5)
+ defer cancel7()
+ checkNoGoroutine()
+}
diff --git a/go/src/context/example_test.go b/go/src/context/example_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..be8cd8376e173678e1f38c7d09806cce9ac8ecba
--- /dev/null
+++ b/go/src/context/example_test.go
@@ -0,0 +1,263 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package context_test
+
+import (
+ "context"
+ "errors"
+ "fmt"
+ "net"
+ "sync"
+ "time"
+)
+
+var neverReady = make(chan struct{}) // never closed
+
+// This example demonstrates the use of a cancelable context to prevent a
+// goroutine leak. By the end of the example function, the goroutine started
+// by gen will return without leaking.
+func ExampleWithCancel() {
+ // gen generates integers in a separate goroutine and
+ // sends them to the returned channel.
+ // The callers of gen need to cancel the context once
+ // they are done consuming generated integers not to leak
+ // the internal goroutine started by gen.
+ gen := func(ctx context.Context) <-chan int {
+ dst := make(chan int)
+ n := 1
+ go func() {
+ for {
+ select {
+ case <-ctx.Done():
+ return // returning not to leak the goroutine
+ case dst <- n:
+ n++
+ }
+ }
+ }()
+ return dst
+ }
+
+ ctx, cancel := context.WithCancel(context.Background())
+ defer cancel() // cancel when we are finished consuming integers
+
+ for n := range gen(ctx) {
+ fmt.Println(n)
+ if n == 5 {
+ break
+ }
+ }
+ // Output:
+ // 1
+ // 2
+ // 3
+ // 4
+ // 5
+}
+
+// This example passes a context with an arbitrary deadline to tell a blocking
+// function that it should abandon its work as soon as it gets to it.
+func ExampleWithDeadline() {
+ d := time.Now().Add(shortDuration)
+ ctx, cancel := context.WithDeadline(context.Background(), d)
+
+ // Even though ctx will be expired, it is good practice to call its
+ // cancellation function in any case. Failure to do so may keep the
+ // context and its parent alive longer than necessary.
+ defer cancel()
+
+ select {
+ case <-neverReady:
+ fmt.Println("ready")
+ case <-ctx.Done():
+ fmt.Println(ctx.Err())
+ }
+
+ // Output:
+ // context deadline exceeded
+}
+
+// This example passes a context with a timeout to tell a blocking function that
+// it should abandon its work after the timeout elapses.
+func ExampleWithTimeout() {
+ // Pass a context with a timeout to tell a blocking function that it
+ // should abandon its work after the timeout elapses.
+ ctx, cancel := context.WithTimeout(context.Background(), shortDuration)
+ defer cancel()
+
+ select {
+ case <-neverReady:
+ fmt.Println("ready")
+ case <-ctx.Done():
+ fmt.Println(ctx.Err()) // prints "context deadline exceeded"
+ }
+
+ // Output:
+ // context deadline exceeded
+}
+
+// This example demonstrates how a value can be passed to the context
+// and also how to retrieve it if it exists.
+func ExampleWithValue() {
+ type favContextKey string
+
+ f := func(ctx context.Context, k favContextKey) {
+ if v := ctx.Value(k); v != nil {
+ fmt.Println("found value:", v)
+ return
+ }
+ fmt.Println("key not found:", k)
+ }
+
+ k := favContextKey("language")
+ ctx := context.WithValue(context.Background(), k, "Go")
+
+ f(ctx, k)
+ f(ctx, favContextKey("color"))
+
+ // Output:
+ // found value: Go
+ // key not found: color
+}
+
+// This example uses AfterFunc to define a function which waits on a sync.Cond,
+// stopping the wait when a context is canceled.
+func ExampleAfterFunc_cond() {
+ waitOnCond := func(ctx context.Context, cond *sync.Cond, conditionMet func() bool) error {
+ stopf := context.AfterFunc(ctx, func() {
+ // We need to acquire cond.L here to be sure that the Broadcast
+ // below won't occur before the call to Wait, which would result
+ // in a missed signal (and deadlock).
+ cond.L.Lock()
+ defer cond.L.Unlock()
+
+ // If multiple goroutines are waiting on cond simultaneously,
+ // we need to make sure we wake up exactly this one.
+ // That means that we need to Broadcast to all of the goroutines,
+ // which will wake them all up.
+ //
+ // If there are N concurrent calls to waitOnCond, each of the goroutines
+ // will spuriously wake up O(N) other goroutines that aren't ready yet,
+ // so this will cause the overall CPU cost to be O(N²).
+ cond.Broadcast()
+ })
+ defer stopf()
+
+ // Since the wakeups are using Broadcast instead of Signal, this call to
+ // Wait may unblock due to some other goroutine's context being canceled,
+ // so to be sure that ctx is actually canceled we need to check it in a loop.
+ for !conditionMet() {
+ cond.Wait()
+ if ctx.Err() != nil {
+ return ctx.Err()
+ }
+ }
+
+ return nil
+ }
+
+ cond := sync.NewCond(new(sync.Mutex))
+
+ var wg sync.WaitGroup
+ for i := 0; i < 4; i++ {
+ wg.Add(1)
+ go func() {
+ defer wg.Done()
+
+ ctx, cancel := context.WithTimeout(context.Background(), 1*time.Millisecond)
+ defer cancel()
+
+ cond.L.Lock()
+ defer cond.L.Unlock()
+
+ err := waitOnCond(ctx, cond, func() bool { return false })
+ fmt.Println(err)
+ }()
+ }
+ wg.Wait()
+
+ // Output:
+ // context deadline exceeded
+ // context deadline exceeded
+ // context deadline exceeded
+ // context deadline exceeded
+}
+
+// This example uses AfterFunc to define a function which reads from a net.Conn,
+// stopping the read when a context is canceled.
+func ExampleAfterFunc_connection() {
+ readFromConn := func(ctx context.Context, conn net.Conn, b []byte) (n int, err error) {
+ stopc := make(chan struct{})
+ stop := context.AfterFunc(ctx, func() {
+ conn.SetReadDeadline(time.Now())
+ close(stopc)
+ })
+ n, err = conn.Read(b)
+ if !stop() {
+ // The AfterFunc was started.
+ // Wait for it to complete, and reset the Conn's deadline.
+ <-stopc
+ conn.SetReadDeadline(time.Time{})
+ return n, ctx.Err()
+ }
+ return n, err
+ }
+
+ listener, err := net.Listen("tcp", "localhost:0")
+ if err != nil {
+ fmt.Println(err)
+ return
+ }
+ defer listener.Close()
+
+ conn, err := net.Dial(listener.Addr().Network(), listener.Addr().String())
+ if err != nil {
+ fmt.Println(err)
+ return
+ }
+ defer conn.Close()
+
+ ctx, cancel := context.WithTimeout(context.Background(), 1*time.Millisecond)
+ defer cancel()
+
+ b := make([]byte, 1024)
+ _, err = readFromConn(ctx, conn, b)
+ fmt.Println(err)
+
+ // Output:
+ // context deadline exceeded
+}
+
+// This example uses AfterFunc to define a function which combines
+// the cancellation signals of two Contexts.
+func ExampleAfterFunc_merge() {
+ // mergeCancel returns a context that contains the values of ctx,
+ // and which is canceled when either ctx or cancelCtx is canceled.
+ mergeCancel := func(ctx, cancelCtx context.Context) (context.Context, context.CancelFunc) {
+ ctx, cancel := context.WithCancelCause(ctx)
+ stop := context.AfterFunc(cancelCtx, func() {
+ cancel(context.Cause(cancelCtx))
+ })
+ return ctx, func() {
+ stop()
+ cancel(context.Canceled)
+ }
+ }
+
+ ctx1, cancel1 := context.WithCancelCause(context.Background())
+ defer cancel1(errors.New("ctx1 canceled"))
+
+ ctx2, cancel2 := context.WithCancelCause(context.Background())
+
+ mergedCtx, mergedCancel := mergeCancel(ctx1, ctx2)
+ defer mergedCancel()
+
+ cancel2(errors.New("ctx2 canceled"))
+ <-mergedCtx.Done()
+ fmt.Println(context.Cause(mergedCtx))
+
+ // Output:
+ // ctx2 canceled
+}
diff --git a/go/src/context/net_test.go b/go/src/context/net_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..a007689d363713a4c548623ef934c6bb83918ade
--- /dev/null
+++ b/go/src/context/net_test.go
@@ -0,0 +1,21 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package context_test
+
+import (
+ "context"
+ "net"
+ "testing"
+)
+
+func TestDeadlineExceededIsNetError(t *testing.T) {
+ err, ok := context.DeadlineExceeded.(net.Error)
+ if !ok {
+ t.Fatal("DeadlineExceeded does not implement net.Error")
+ }
+ if !err.Timeout() || !err.Temporary() {
+ t.Fatalf("Timeout() = %v, Temporary() = %v, want true, true", err.Timeout(), err.Temporary())
+ }
+}
diff --git a/go/src/context/x_test.go b/go/src/context/x_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..aeb5470399f4eec82a32533c24079f8c653dd2c9
--- /dev/null
+++ b/go/src/context/x_test.go
@@ -0,0 +1,1198 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package context_test
+
+import (
+ . "context"
+ "errors"
+ "fmt"
+ "internal/asan"
+ "math/rand"
+ "runtime"
+ "strings"
+ "sync"
+ "testing"
+ "time"
+)
+
+// Each XTestFoo in context_test.go must be called from a TestFoo here to run.
+func TestParentFinishesChild(t *testing.T) {
+ XTestParentFinishesChild(t) // uses unexported context types
+}
+func TestChildFinishesFirst(t *testing.T) {
+ XTestChildFinishesFirst(t) // uses unexported context types
+}
+func TestCancelRemoves(t *testing.T) {
+ XTestCancelRemoves(t) // uses unexported context types
+}
+func TestCustomContextGoroutines(t *testing.T) {
+ XTestCustomContextGoroutines(t) // reads the context.goroutines counter
+}
+
+// The following are regular tests in package context_test.
+
+// otherContext is a Context that's not one of the types defined in context.go.
+// This lets us test code paths that differ based on the underlying type of the
+// Context.
+type otherContext struct {
+ Context
+}
+
+const (
+ shortDuration = 1 * time.Millisecond // a reasonable duration to block in a test
+ veryLongDuration = 1000 * time.Hour // an arbitrary upper bound on the test's running time
+)
+
+// quiescent returns an arbitrary duration by which the program should have
+// completed any remaining work and reached a steady (idle) state.
+func quiescent(t *testing.T) time.Duration {
+ deadline, ok := t.Deadline()
+ if !ok {
+ return 5 * time.Second
+ }
+
+ const arbitraryCleanupMargin = 1 * time.Second
+ return time.Until(deadline) - arbitraryCleanupMargin
+}
+func TestBackground(t *testing.T) {
+ c := Background()
+ if c == nil {
+ t.Fatalf("Background returned nil")
+ }
+ select {
+ case x := <-c.Done():
+ t.Errorf("<-c.Done() == %v want nothing (it should block)", x)
+ default:
+ }
+ if got, want := fmt.Sprint(c), "context.Background"; got != want {
+ t.Errorf("Background().String() = %q want %q", got, want)
+ }
+}
+
+func TestTODO(t *testing.T) {
+ c := TODO()
+ if c == nil {
+ t.Fatalf("TODO returned nil")
+ }
+ select {
+ case x := <-c.Done():
+ t.Errorf("<-c.Done() == %v want nothing (it should block)", x)
+ default:
+ }
+ if got, want := fmt.Sprint(c), "context.TODO"; got != want {
+ t.Errorf("TODO().String() = %q want %q", got, want)
+ }
+}
+
+func TestWithCancel(t *testing.T) {
+ c1, cancel := WithCancel(Background())
+
+ if got, want := fmt.Sprint(c1), "context.Background.WithCancel"; got != want {
+ t.Errorf("c1.String() = %q want %q", got, want)
+ }
+
+ o := otherContext{c1}
+ c2, _ := WithCancel(o)
+ contexts := []Context{c1, o, c2}
+
+ for i, c := range contexts {
+ if d := c.Done(); d == nil {
+ t.Errorf("c[%d].Done() == %v want non-nil", i, d)
+ }
+ if e := c.Err(); e != nil {
+ t.Errorf("c[%d].Err() == %v want nil", i, e)
+ }
+
+ select {
+ case x := <-c.Done():
+ t.Errorf("<-c.Done() == %v want nothing (it should block)", x)
+ default:
+ }
+ }
+
+ cancel() // Should propagate synchronously.
+ for i, c := range contexts {
+ select {
+ case <-c.Done():
+ default:
+ t.Errorf("<-c[%d].Done() blocked, but shouldn't have", i)
+ }
+ if e := c.Err(); e != Canceled {
+ t.Errorf("c[%d].Err() == %v want %v", i, e, Canceled)
+ }
+ }
+}
+
+func testDeadline(c Context, name string, t *testing.T) {
+ t.Helper()
+ d := quiescent(t)
+ timer := time.NewTimer(d)
+ defer timer.Stop()
+ select {
+ case <-timer.C:
+ t.Fatalf("%s: context not timed out after %v", name, d)
+ case <-c.Done():
+ }
+ if e := c.Err(); e != DeadlineExceeded {
+ t.Errorf("%s: c.Err() == %v; want %v", name, e, DeadlineExceeded)
+ }
+}
+
+func TestDeadline(t *testing.T) {
+ t.Parallel()
+
+ c, _ := WithDeadline(Background(), time.Now().Add(shortDuration))
+ if got, prefix := fmt.Sprint(c), "context.Background.WithDeadline("; !strings.HasPrefix(got, prefix) {
+ t.Errorf("c.String() = %q want prefix %q", got, prefix)
+ }
+ testDeadline(c, "WithDeadline", t)
+
+ c, _ = WithDeadline(Background(), time.Now().Add(shortDuration))
+ o := otherContext{c}
+ testDeadline(o, "WithDeadline+otherContext", t)
+
+ c, _ = WithDeadline(Background(), time.Now().Add(shortDuration))
+ o = otherContext{c}
+ c, _ = WithDeadline(o, time.Now().Add(veryLongDuration))
+ testDeadline(c, "WithDeadline+otherContext+WithDeadline", t)
+
+ c, _ = WithDeadline(Background(), time.Now().Add(-shortDuration))
+ testDeadline(c, "WithDeadline+inthepast", t)
+
+ c, _ = WithDeadline(Background(), time.Now())
+ testDeadline(c, "WithDeadline+now", t)
+}
+
+func TestTimeout(t *testing.T) {
+ t.Parallel()
+
+ c, _ := WithTimeout(Background(), shortDuration)
+ if got, prefix := fmt.Sprint(c), "context.Background.WithDeadline("; !strings.HasPrefix(got, prefix) {
+ t.Errorf("c.String() = %q want prefix %q", got, prefix)
+ }
+ testDeadline(c, "WithTimeout", t)
+
+ c, _ = WithTimeout(Background(), shortDuration)
+ o := otherContext{c}
+ testDeadline(o, "WithTimeout+otherContext", t)
+
+ c, _ = WithTimeout(Background(), shortDuration)
+ o = otherContext{c}
+ c, _ = WithTimeout(o, veryLongDuration)
+ testDeadline(c, "WithTimeout+otherContext+WithTimeout", t)
+}
+
+func TestCanceledTimeout(t *testing.T) {
+ c, _ := WithTimeout(Background(), time.Second)
+ o := otherContext{c}
+ c, cancel := WithTimeout(o, veryLongDuration)
+ cancel() // Should propagate synchronously.
+ select {
+ case <-c.Done():
+ default:
+ t.Errorf("<-c.Done() blocked, but shouldn't have")
+ }
+ if e := c.Err(); e != Canceled {
+ t.Errorf("c.Err() == %v want %v", e, Canceled)
+ }
+}
+
+type key1 int
+type key2 int
+
+func (k key2) String() string { return fmt.Sprintf("%[1]T(%[1]d)", k) }
+
+var k1 = key1(1)
+var k2 = key2(1) // same int as k1, different type
+var k3 = key2(3) // same type as k2, different int
+
+func TestValues(t *testing.T) {
+ check := func(c Context, nm, v1, v2, v3 string) {
+ if v, ok := c.Value(k1).(string); ok == (len(v1) == 0) || v != v1 {
+ t.Errorf(`%s.Value(k1).(string) = %q, %t want %q, %t`, nm, v, ok, v1, len(v1) != 0)
+ }
+ if v, ok := c.Value(k2).(string); ok == (len(v2) == 0) || v != v2 {
+ t.Errorf(`%s.Value(k2).(string) = %q, %t want %q, %t`, nm, v, ok, v2, len(v2) != 0)
+ }
+ if v, ok := c.Value(k3).(string); ok == (len(v3) == 0) || v != v3 {
+ t.Errorf(`%s.Value(k3).(string) = %q, %t want %q, %t`, nm, v, ok, v3, len(v3) != 0)
+ }
+ }
+
+ c0 := Background()
+ check(c0, "c0", "", "", "")
+
+ c1 := WithValue(Background(), k1, "c1k1")
+ check(c1, "c1", "c1k1", "", "")
+
+ if got, want := fmt.Sprint(c1), `context.Background.WithValue(context_test.key1, c1k1)`; got != want {
+ t.Errorf("c.String() = %q want %q", got, want)
+ }
+
+ c2 := WithValue(c1, k2, "c2k2")
+ check(c2, "c2", "c1k1", "c2k2", "")
+
+ if got, want := fmt.Sprint(c2), `context.Background.WithValue(context_test.key1, c1k1).WithValue(context_test.key2(1), c2k2)`; got != want {
+ t.Errorf("c.String() = %q want %q", got, want)
+ }
+
+ c3 := WithValue(c2, k3, "c3k3")
+ check(c3, "c2", "c1k1", "c2k2", "c3k3")
+
+ c4 := WithValue(c3, k1, nil)
+ check(c4, "c4", "", "c2k2", "c3k3")
+
+ if got, want := fmt.Sprint(c4), `context.Background.WithValue(context_test.key1, c1k1).WithValue(context_test.key2(1), c2k2).WithValue(context_test.key2(3), c3k3).WithValue(context_test.key1, )`; got != want {
+ t.Errorf("c.String() = %q want %q", got, want)
+ }
+
+ o0 := otherContext{Background()}
+ check(o0, "o0", "", "", "")
+
+ o1 := otherContext{WithValue(Background(), k1, "c1k1")}
+ check(o1, "o1", "c1k1", "", "")
+
+ o2 := WithValue(o1, k2, "o2k2")
+ check(o2, "o2", "c1k1", "o2k2", "")
+
+ o3 := otherContext{c4}
+ check(o3, "o3", "", "c2k2", "c3k3")
+
+ o4 := WithValue(o3, k3, nil)
+ check(o4, "o4", "", "c2k2", "")
+}
+
+func TestAllocs(t *testing.T) {
+ if asan.Enabled {
+ t.Skip("test allocates more with -asan")
+ }
+ bg := Background()
+ for _, test := range []struct {
+ desc string
+ f func()
+ limit float64
+ gccgoLimit float64
+ }{
+ {
+ desc: "Background()",
+ f: func() { Background() },
+ limit: 0,
+ gccgoLimit: 0,
+ },
+ {
+ desc: fmt.Sprintf("WithValue(bg, %v, nil)", k1),
+ f: func() {
+ c := WithValue(bg, k1, nil)
+ c.Value(k1)
+ },
+ limit: 3,
+ gccgoLimit: 3,
+ },
+ {
+ desc: "WithTimeout(bg, 1*time.Nanosecond)",
+ f: func() {
+ c, _ := WithTimeout(bg, 1*time.Nanosecond)
+ <-c.Done()
+ },
+ limit: 12,
+ gccgoLimit: 15,
+ },
+ {
+ desc: "WithCancel(bg)",
+ f: func() {
+ c, cancel := WithCancel(bg)
+ cancel()
+ <-c.Done()
+ },
+ limit: 5,
+ gccgoLimit: 8,
+ },
+ {
+ desc: "WithTimeout(bg, 5*time.Millisecond)",
+ f: func() {
+ c, cancel := WithTimeout(bg, 5*time.Millisecond)
+ cancel()
+ <-c.Done()
+ },
+ limit: 8,
+ gccgoLimit: 25,
+ },
+ } {
+ limit := test.limit
+ if runtime.Compiler == "gccgo" {
+ // gccgo does not yet do escape analysis.
+ // TODO(iant): Remove this when gccgo does do escape analysis.
+ limit = test.gccgoLimit
+ }
+ numRuns := 100
+ if testing.Short() {
+ numRuns = 10
+ }
+ if n := testing.AllocsPerRun(numRuns, test.f); n > limit {
+ t.Errorf("%s allocs = %f want %d", test.desc, n, int(limit))
+ }
+ }
+}
+
+func TestSimultaneousCancels(t *testing.T) {
+ root, cancel := WithCancel(Background())
+ m := map[Context]CancelFunc{root: cancel}
+ q := []Context{root}
+ // Create a tree of contexts.
+ for len(q) != 0 && len(m) < 100 {
+ parent := q[0]
+ q = q[1:]
+ for i := 0; i < 4; i++ {
+ ctx, cancel := WithCancel(parent)
+ m[ctx] = cancel
+ q = append(q, ctx)
+ }
+ }
+ // Start all the cancels in a random order.
+ var wg sync.WaitGroup
+ wg.Add(len(m))
+ for _, cancel := range m {
+ go func(cancel CancelFunc) {
+ cancel()
+ wg.Done()
+ }(cancel)
+ }
+
+ d := quiescent(t)
+ stuck := make(chan struct{})
+ timer := time.AfterFunc(d, func() { close(stuck) })
+ defer timer.Stop()
+
+ // Wait on all the contexts in a random order.
+ for ctx := range m {
+ select {
+ case <-ctx.Done():
+ case <-stuck:
+ buf := make([]byte, 10<<10)
+ n := runtime.Stack(buf, true)
+ t.Fatalf("timed out after %v waiting for <-ctx.Done(); stacks:\n%s", d, buf[:n])
+ }
+ }
+ // Wait for all the cancel functions to return.
+ done := make(chan struct{})
+ go func() {
+ wg.Wait()
+ close(done)
+ }()
+ select {
+ case <-done:
+ case <-stuck:
+ buf := make([]byte, 10<<10)
+ n := runtime.Stack(buf, true)
+ t.Fatalf("timed out after %v waiting for cancel functions; stacks:\n%s", d, buf[:n])
+ }
+}
+
+func TestInterlockedCancels(t *testing.T) {
+ parent, cancelParent := WithCancel(Background())
+ child, cancelChild := WithCancel(parent)
+ go func() {
+ <-parent.Done()
+ cancelChild()
+ }()
+ cancelParent()
+ d := quiescent(t)
+ timer := time.NewTimer(d)
+ defer timer.Stop()
+ select {
+ case <-child.Done():
+ case <-timer.C:
+ buf := make([]byte, 10<<10)
+ n := runtime.Stack(buf, true)
+ t.Fatalf("timed out after %v waiting for child.Done(); stacks:\n%s", d, buf[:n])
+ }
+}
+
+func TestLayersCancel(t *testing.T) {
+ testLayers(t, time.Now().UnixNano(), false)
+}
+
+func TestLayersTimeout(t *testing.T) {
+ testLayers(t, time.Now().UnixNano(), true)
+}
+
+func testLayers(t *testing.T, seed int64, testTimeout bool) {
+ t.Parallel()
+
+ r := rand.New(rand.NewSource(seed))
+ prefix := fmt.Sprintf("seed=%d", seed)
+ errorf := func(format string, a ...any) {
+ t.Errorf(prefix+format, a...)
+ }
+ const (
+ minLayers = 30
+ )
+ type value int
+ var (
+ vals []*value
+ cancels []CancelFunc
+ numTimers int
+ ctx = Background()
+ )
+ for i := 0; i < minLayers || numTimers == 0 || len(cancels) == 0 || len(vals) == 0; i++ {
+ switch r.Intn(3) {
+ case 0:
+ v := new(value)
+ ctx = WithValue(ctx, v, v)
+ vals = append(vals, v)
+ case 1:
+ var cancel CancelFunc
+ ctx, cancel = WithCancel(ctx)
+ cancels = append(cancels, cancel)
+ case 2:
+ var cancel CancelFunc
+ d := veryLongDuration
+ if testTimeout {
+ d = shortDuration
+ }
+ ctx, cancel = WithTimeout(ctx, d)
+ cancels = append(cancels, cancel)
+ numTimers++
+ }
+ }
+ checkValues := func(when string) {
+ for _, key := range vals {
+ if val := ctx.Value(key).(*value); key != val {
+ errorf("%s: ctx.Value(%p) = %p want %p", when, key, val, key)
+ }
+ }
+ }
+ if !testTimeout {
+ select {
+ case <-ctx.Done():
+ errorf("ctx should not be canceled yet")
+ default:
+ }
+ }
+ if s, prefix := fmt.Sprint(ctx), "context.Background."; !strings.HasPrefix(s, prefix) {
+ t.Errorf("ctx.String() = %q want prefix %q", s, prefix)
+ }
+ t.Log(ctx)
+ checkValues("before cancel")
+ if testTimeout {
+ d := quiescent(t)
+ timer := time.NewTimer(d)
+ defer timer.Stop()
+ select {
+ case <-ctx.Done():
+ case <-timer.C:
+ errorf("ctx should have timed out after %v", d)
+ }
+ checkValues("after timeout")
+ } else {
+ cancel := cancels[r.Intn(len(cancels))]
+ cancel()
+ select {
+ case <-ctx.Done():
+ default:
+ errorf("ctx should be canceled")
+ }
+ checkValues("after cancel")
+ }
+}
+
+func TestWithCancelCanceledParent(t *testing.T) {
+ parent, pcancel := WithCancelCause(Background())
+ cause := fmt.Errorf("Because!")
+ pcancel(cause)
+
+ c, _ := WithCancel(parent)
+ select {
+ case <-c.Done():
+ default:
+ t.Errorf("child not done immediately upon construction")
+ }
+ if got, want := c.Err(), Canceled; got != want {
+ t.Errorf("child not canceled; got = %v, want = %v", got, want)
+ }
+ if got, want := Cause(c), cause; got != want {
+ t.Errorf("child has wrong cause; got = %v, want = %v", got, want)
+ }
+}
+
+func TestWithCancelSimultaneouslyCanceledParent(t *testing.T) {
+ // Cancel the parent goroutine concurrently with creating a child.
+ for i := 0; i < 100; i++ {
+ parent, pcancel := WithCancelCause(Background())
+ cause := fmt.Errorf("Because!")
+ go pcancel(cause)
+
+ c, _ := WithCancel(parent)
+ <-c.Done()
+ if got, want := c.Err(), Canceled; got != want {
+ t.Errorf("child not canceled; got = %v, want = %v", got, want)
+ }
+ if got, want := Cause(c), cause; got != want {
+ t.Errorf("child has wrong cause; got = %v, want = %v", got, want)
+ }
+ }
+}
+
+func TestWithValueChecksKey(t *testing.T) {
+ panicVal := recoveredValue(func() { _ = WithValue(Background(), []byte("foo"), "bar") })
+ if panicVal == nil {
+ t.Error("expected panic")
+ }
+ panicVal = recoveredValue(func() { _ = WithValue(Background(), nil, "bar") })
+ if got, want := fmt.Sprint(panicVal), "nil key"; got != want {
+ t.Errorf("panic = %q; want %q", got, want)
+ }
+}
+
+func TestInvalidDerivedFail(t *testing.T) {
+ panicVal := recoveredValue(func() { _, _ = WithCancel(nil) })
+ if panicVal == nil {
+ t.Error("expected panic")
+ }
+ panicVal = recoveredValue(func() { _, _ = WithDeadline(nil, time.Now().Add(shortDuration)) })
+ if panicVal == nil {
+ t.Error("expected panic")
+ }
+ panicVal = recoveredValue(func() { _ = WithValue(nil, "foo", "bar") })
+ if panicVal == nil {
+ t.Error("expected panic")
+ }
+}
+
+func recoveredValue(fn func()) (v any) {
+ defer func() { v = recover() }()
+ fn()
+ return
+}
+
+func TestDeadlineExceededSupportsTimeout(t *testing.T) {
+ i, ok := DeadlineExceeded.(interface {
+ Timeout() bool
+ })
+ if !ok {
+ t.Fatal("DeadlineExceeded does not support Timeout interface")
+ }
+ if !i.Timeout() {
+ t.Fatal("wrong value for timeout")
+ }
+}
+func TestCause(t *testing.T) {
+ var (
+ forever = 1e6 * time.Second
+ parentCause = fmt.Errorf("parentCause")
+ childCause = fmt.Errorf("childCause")
+ tooSlow = fmt.Errorf("tooSlow")
+ finishedEarly = fmt.Errorf("finishedEarly")
+ )
+ for _, test := range []struct {
+ name string
+ ctx func() Context
+ err error
+ cause error
+ }{
+ {
+ name: "Background",
+ ctx: Background,
+ err: nil,
+ cause: nil,
+ },
+ {
+ name: "TODO",
+ ctx: TODO,
+ err: nil,
+ cause: nil,
+ },
+ {
+ name: "WithCancel",
+ ctx: func() Context {
+ ctx, cancel := WithCancel(Background())
+ cancel()
+ return ctx
+ },
+ err: Canceled,
+ cause: Canceled,
+ },
+ {
+ name: "WithCancelCause",
+ ctx: func() Context {
+ ctx, cancel := WithCancelCause(Background())
+ cancel(parentCause)
+ return ctx
+ },
+ err: Canceled,
+ cause: parentCause,
+ },
+ {
+ name: "WithCancelCause nil",
+ ctx: func() Context {
+ ctx, cancel := WithCancelCause(Background())
+ cancel(nil)
+ return ctx
+ },
+ err: Canceled,
+ cause: Canceled,
+ },
+ {
+ name: "WithCancelCause: parent cause before child",
+ ctx: func() Context {
+ ctx, cancelParent := WithCancelCause(Background())
+ ctx, cancelChild := WithCancelCause(ctx)
+ cancelParent(parentCause)
+ cancelChild(childCause)
+ return ctx
+ },
+ err: Canceled,
+ cause: parentCause,
+ },
+ {
+ name: "WithCancelCause: parent cause after child",
+ ctx: func() Context {
+ ctx, cancelParent := WithCancelCause(Background())
+ ctx, cancelChild := WithCancelCause(ctx)
+ cancelChild(childCause)
+ cancelParent(parentCause)
+ return ctx
+ },
+ err: Canceled,
+ cause: childCause,
+ },
+ {
+ name: "WithCancelCause: parent cause before nil",
+ ctx: func() Context {
+ ctx, cancelParent := WithCancelCause(Background())
+ ctx, cancelChild := WithCancel(ctx)
+ cancelParent(parentCause)
+ cancelChild()
+ return ctx
+ },
+ err: Canceled,
+ cause: parentCause,
+ },
+ {
+ name: "WithCancelCause: parent cause after nil",
+ ctx: func() Context {
+ ctx, cancelParent := WithCancelCause(Background())
+ ctx, cancelChild := WithCancel(ctx)
+ cancelChild()
+ cancelParent(parentCause)
+ return ctx
+ },
+ err: Canceled,
+ cause: Canceled,
+ },
+ {
+ name: "WithCancelCause: child cause after nil",
+ ctx: func() Context {
+ ctx, cancelParent := WithCancel(Background())
+ ctx, cancelChild := WithCancelCause(ctx)
+ cancelParent()
+ cancelChild(childCause)
+ return ctx
+ },
+ err: Canceled,
+ cause: Canceled,
+ },
+ {
+ name: "WithCancelCause: child cause before nil",
+ ctx: func() Context {
+ ctx, cancelParent := WithCancel(Background())
+ ctx, cancelChild := WithCancelCause(ctx)
+ cancelChild(childCause)
+ cancelParent()
+ return ctx
+ },
+ err: Canceled,
+ cause: childCause,
+ },
+ {
+ name: "WithTimeout",
+ ctx: func() Context {
+ ctx, cancel := WithTimeout(Background(), 0)
+ cancel()
+ return ctx
+ },
+ err: DeadlineExceeded,
+ cause: DeadlineExceeded,
+ },
+ {
+ name: "WithTimeout canceled",
+ ctx: func() Context {
+ ctx, cancel := WithTimeout(Background(), forever)
+ cancel()
+ return ctx
+ },
+ err: Canceled,
+ cause: Canceled,
+ },
+ {
+ name: "WithTimeoutCause",
+ ctx: func() Context {
+ ctx, cancel := WithTimeoutCause(Background(), 0, tooSlow)
+ cancel()
+ return ctx
+ },
+ err: DeadlineExceeded,
+ cause: tooSlow,
+ },
+ {
+ name: "WithTimeoutCause canceled",
+ ctx: func() Context {
+ ctx, cancel := WithTimeoutCause(Background(), forever, tooSlow)
+ cancel()
+ return ctx
+ },
+ err: Canceled,
+ cause: Canceled,
+ },
+ {
+ name: "WithTimeoutCause stacked",
+ ctx: func() Context {
+ ctx, cancel := WithCancelCause(Background())
+ ctx, _ = WithTimeoutCause(ctx, 0, tooSlow)
+ cancel(finishedEarly)
+ return ctx
+ },
+ err: DeadlineExceeded,
+ cause: tooSlow,
+ },
+ {
+ name: "WithTimeoutCause stacked canceled",
+ ctx: func() Context {
+ ctx, cancel := WithCancelCause(Background())
+ ctx, _ = WithTimeoutCause(ctx, forever, tooSlow)
+ cancel(finishedEarly)
+ return ctx
+ },
+ err: Canceled,
+ cause: finishedEarly,
+ },
+ {
+ name: "WithoutCancel",
+ ctx: func() Context {
+ return WithoutCancel(Background())
+ },
+ err: nil,
+ cause: nil,
+ },
+ {
+ name: "WithoutCancel canceled",
+ ctx: func() Context {
+ ctx, cancel := WithCancelCause(Background())
+ ctx = WithoutCancel(ctx)
+ cancel(finishedEarly)
+ return ctx
+ },
+ err: nil,
+ cause: nil,
+ },
+ {
+ name: "WithoutCancel timeout",
+ ctx: func() Context {
+ ctx, cancel := WithTimeoutCause(Background(), 0, tooSlow)
+ ctx = WithoutCancel(ctx)
+ cancel()
+ return ctx
+ },
+ err: nil,
+ cause: nil,
+ },
+ {
+ name: "parent of custom context not canceled",
+ ctx: func() Context {
+ ctx, _ := WithCancelCause(Background())
+ ctx, cancel2 := newCustomContext(ctx)
+ cancel2()
+ return ctx
+ },
+ err: Canceled,
+ cause: Canceled,
+ },
+ {
+ name: "parent of custom context is canceled before",
+ ctx: func() Context {
+ ctx, cancel1 := WithCancelCause(Background())
+ ctx, cancel2 := newCustomContext(ctx)
+ cancel1(parentCause)
+ cancel2()
+ return ctx
+ },
+ err: Canceled,
+ cause: parentCause,
+ },
+ {
+ name: "parent of custom context is canceled after",
+ ctx: func() Context {
+ ctx, cancel1 := WithCancelCause(Background())
+ ctx, cancel2 := newCustomContext(ctx)
+ cancel2()
+ cancel1(parentCause)
+ return ctx
+ },
+ err: Canceled,
+ // This isn't really right: the child context was canceled before
+ // the parent context, and shouldn't inherit the parent's cause.
+ // However, since the child is a custom context, Cause has no way
+ // to tell which was canceled first and returns the parent's cause.
+ cause: parentCause,
+ },
+ } {
+ t.Run(test.name, func(t *testing.T) {
+ t.Parallel()
+ ctx := test.ctx()
+ if got, want := ctx.Err(), test.err; want != got {
+ t.Errorf("ctx.Err() = %v want %v", got, want)
+ }
+ if got, want := Cause(ctx), test.cause; want != got {
+ t.Errorf("Cause(ctx) = %v want %v", got, want)
+ }
+ })
+ }
+}
+
+func TestCauseRace(t *testing.T) {
+ cause := errors.New("TestCauseRace")
+ ctx, cancel := WithCancelCause(Background())
+ go func() {
+ cancel(cause)
+ }()
+ for {
+ // Poll Cause, rather than waiting for Done, to test that
+ // access to the underlying cause is synchronized properly.
+ if err := Cause(ctx); err != nil {
+ if err != cause {
+ t.Errorf("Cause returned %v, want %v", err, cause)
+ }
+ break
+ }
+ runtime.Gosched()
+ }
+}
+
+func TestWithoutCancel(t *testing.T) {
+ key, value := "key", "value"
+ ctx := WithValue(Background(), key, value)
+ ctx = WithoutCancel(ctx)
+ if d, ok := ctx.Deadline(); !d.IsZero() || ok != false {
+ t.Errorf("ctx.Deadline() = %v, %v want zero, false", d, ok)
+ }
+ if done := ctx.Done(); done != nil {
+ t.Errorf("ctx.Deadline() = %v want nil", done)
+ }
+ if err := ctx.Err(); err != nil {
+ t.Errorf("ctx.Err() = %v want nil", err)
+ }
+ if v := ctx.Value(key); v != value {
+ t.Errorf("ctx.Value(%q) = %q want %q", key, v, value)
+ }
+}
+
+type customDoneContext struct {
+ Context
+ donec chan struct{}
+}
+
+func (c *customDoneContext) Done() <-chan struct{} {
+ return c.donec
+}
+
+func TestCustomContextPropagation(t *testing.T) {
+ cause := errors.New("TestCustomContextPropagation")
+ donec := make(chan struct{})
+ ctx1, cancel1 := WithCancelCause(Background())
+ ctx2 := &customDoneContext{
+ Context: ctx1,
+ donec: donec,
+ }
+ ctx3, cancel3 := WithCancel(ctx2)
+ defer cancel3()
+
+ cancel1(cause)
+ close(donec)
+
+ <-ctx3.Done()
+ if got, want := ctx3.Err(), Canceled; got != want {
+ t.Errorf("child not canceled; got = %v, want = %v", got, want)
+ }
+ if got, want := Cause(ctx3), cause; got != want {
+ t.Errorf("child has wrong cause; got = %v, want = %v", got, want)
+ }
+}
+
+// customCauseContext is a custom Context used to test context.Cause.
+type customCauseContext struct {
+ mu sync.Mutex
+ done chan struct{}
+ err error
+
+ cancelChild CancelFunc
+}
+
+func (ccc *customCauseContext) Deadline() (deadline time.Time, ok bool) {
+ return
+}
+
+func (ccc *customCauseContext) Done() <-chan struct{} {
+ ccc.mu.Lock()
+ defer ccc.mu.Unlock()
+ return ccc.done
+}
+
+func (ccc *customCauseContext) Err() error {
+ ccc.mu.Lock()
+ defer ccc.mu.Unlock()
+ return ccc.err
+}
+
+func (ccc *customCauseContext) Value(key any) any {
+ return nil
+}
+
+func (ccc *customCauseContext) cancel() {
+ ccc.mu.Lock()
+ ccc.err = Canceled
+ close(ccc.done)
+ cancelChild := ccc.cancelChild
+ ccc.mu.Unlock()
+
+ if cancelChild != nil {
+ cancelChild()
+ }
+}
+
+func (ccc *customCauseContext) setCancelChild(cancelChild CancelFunc) {
+ ccc.cancelChild = cancelChild
+}
+
+func TestCustomContextCause(t *testing.T) {
+ // Test if we cancel a custom context, Err and Cause return Canceled.
+ ccc := &customCauseContext{
+ done: make(chan struct{}),
+ }
+ ccc.cancel()
+ if got := ccc.Err(); got != Canceled {
+ t.Errorf("ccc.Err() = %v, want %v", got, Canceled)
+ }
+ if got := Cause(ccc); got != Canceled {
+ t.Errorf("Cause(ccc) = %v, want %v", got, Canceled)
+ }
+
+ // Test that if we pass a custom context to WithCancelCause,
+ // and then cancel that child context with a cause,
+ // that the cause of the child canceled context is correct
+ // but that the parent custom context is not canceled.
+ ccc = &customCauseContext{
+ done: make(chan struct{}),
+ }
+ ctx, causeFunc := WithCancelCause(ccc)
+ cause := errors.New("TestCustomContextCause")
+ causeFunc(cause)
+ if got := ctx.Err(); got != Canceled {
+ t.Errorf("after CancelCauseFunc ctx.Err() = %v, want %v", got, Canceled)
+ }
+ if got := Cause(ctx); got != cause {
+ t.Errorf("after CancelCauseFunc Cause(ctx) = %v, want %v", got, cause)
+ }
+ if got := ccc.Err(); got != nil {
+ t.Errorf("after CancelCauseFunc ccc.Err() = %v, want %v", got, nil)
+ }
+ if got := Cause(ccc); got != nil {
+ t.Errorf("after CancelCauseFunc Cause(ccc) = %v, want %v", got, nil)
+ }
+
+ // Test that if we now cancel the parent custom context,
+ // the cause of the child canceled context is still correct,
+ // and the parent custom context is canceled without a cause.
+ ccc.cancel()
+ if got := ctx.Err(); got != Canceled {
+ t.Errorf("after CancelCauseFunc ctx.Err() = %v, want %v", got, Canceled)
+ }
+ if got := Cause(ctx); got != cause {
+ t.Errorf("after CancelCauseFunc Cause(ctx) = %v, want %v", got, cause)
+ }
+ if got := ccc.Err(); got != Canceled {
+ t.Errorf("after CancelCauseFunc ccc.Err() = %v, want %v", got, Canceled)
+ }
+ if got := Cause(ccc); got != Canceled {
+ t.Errorf("after CancelCauseFunc Cause(ccc) = %v, want %v", got, Canceled)
+ }
+
+ // Test that if we associate a custom context with a child,
+ // then canceling the custom context cancels the child.
+ ccc = &customCauseContext{
+ done: make(chan struct{}),
+ }
+ ctx, cancelFunc := WithCancel(ccc)
+ ccc.setCancelChild(cancelFunc)
+ ccc.cancel()
+ if got := ctx.Err(); got != Canceled {
+ t.Errorf("after CancelCauseFunc ctx.Err() = %v, want %v", got, Canceled)
+ }
+ if got := Cause(ctx); got != Canceled {
+ t.Errorf("after CancelCauseFunc Cause(ctx) = %v, want %v", got, Canceled)
+ }
+ if got := ccc.Err(); got != Canceled {
+ t.Errorf("after CancelCauseFunc ccc.Err() = %v, want %v", got, Canceled)
+ }
+ if got := Cause(ccc); got != Canceled {
+ t.Errorf("after CancelCauseFunc Cause(ccc) = %v, want %v", got, Canceled)
+ }
+}
+
+func TestAfterFuncCalledAfterCancel(t *testing.T) {
+ ctx, cancel := WithCancel(Background())
+ donec := make(chan struct{})
+ stop := AfterFunc(ctx, func() {
+ close(donec)
+ })
+ select {
+ case <-donec:
+ t.Fatalf("AfterFunc called before context is done")
+ case <-time.After(shortDuration):
+ }
+ cancel()
+ select {
+ case <-donec:
+ case <-time.After(veryLongDuration):
+ t.Fatalf("AfterFunc not called after context is canceled")
+ }
+ if stop() {
+ t.Fatalf("stop() = true, want false")
+ }
+}
+
+func TestAfterFuncCalledAfterTimeout(t *testing.T) {
+ ctx, cancel := WithTimeout(Background(), shortDuration)
+ defer cancel()
+ donec := make(chan struct{})
+ AfterFunc(ctx, func() {
+ close(donec)
+ })
+ select {
+ case <-donec:
+ case <-time.After(veryLongDuration):
+ t.Fatalf("AfterFunc not called after context is canceled")
+ }
+}
+
+func TestAfterFuncCalledImmediately(t *testing.T) {
+ ctx, cancel := WithCancel(Background())
+ cancel()
+ donec := make(chan struct{})
+ AfterFunc(ctx, func() {
+ close(donec)
+ })
+ select {
+ case <-donec:
+ case <-time.After(veryLongDuration):
+ t.Fatalf("AfterFunc not called for already-canceled context")
+ }
+}
+
+func TestAfterFuncNotCalledAfterStop(t *testing.T) {
+ ctx, cancel := WithCancel(Background())
+ donec := make(chan struct{})
+ stop := AfterFunc(ctx, func() {
+ close(donec)
+ })
+ if !stop() {
+ t.Fatalf("stop() = false, want true")
+ }
+ cancel()
+ select {
+ case <-donec:
+ t.Fatalf("AfterFunc called for already-canceled context")
+ case <-time.After(shortDuration):
+ }
+ if stop() {
+ t.Fatalf("stop() = true, want false")
+ }
+}
+
+// This test verifies that canceling a context does not block waiting for AfterFuncs to finish.
+func TestAfterFuncCalledAsynchronously(t *testing.T) {
+ ctx, cancel := WithCancel(Background())
+ donec := make(chan struct{})
+ stop := AfterFunc(ctx, func() {
+ // The channel send blocks until donec is read from.
+ donec <- struct{}{}
+ })
+ defer stop()
+ cancel()
+ // After cancel returns, read from donec and unblock the AfterFunc.
+ select {
+ case <-donec:
+ case <-time.After(veryLongDuration):
+ t.Fatalf("AfterFunc not called after context is canceled")
+ }
+}
+
+// customContext is a custom Context implementation.
+type customContext struct {
+ parent Context
+
+ doneOnce sync.Once
+ donec chan struct{}
+ err error
+}
+
+func newCustomContext(parent Context) (Context, CancelFunc) {
+ c := &customContext{
+ parent: parent,
+ donec: make(chan struct{}),
+ }
+ AfterFunc(parent, func() {
+ c.doneOnce.Do(func() {
+ c.err = parent.Err()
+ close(c.donec)
+ })
+ })
+ return c, func() {
+ c.doneOnce.Do(func() {
+ c.err = Canceled
+ close(c.donec)
+ })
+ }
+}
+
+func (c *customContext) Deadline() (time.Time, bool) {
+ return c.parent.Deadline()
+}
+
+func (c *customContext) Done() <-chan struct{} {
+ return c.donec
+}
+
+func (c *customContext) Err() error {
+ select {
+ case <-c.donec:
+ return c.err
+ default:
+ return nil
+ }
+}
+
+func (c *customContext) Value(key any) any {
+ return c.parent.Value(key)
+}
+
+// Issue #75533.
+func TestContextErrDoneRace(t *testing.T) {
+ // 4 iterations reliably reproduced #75533.
+ for range 10 {
+ ctx, cancel := WithCancel(Background())
+ donec := ctx.Done()
+ go cancel()
+ for ctx.Err() == nil {
+ if runtime.GOARCH == "wasm" {
+ runtime.Gosched() // need to explicitly yield
+ }
+ }
+ select {
+ case <-donec:
+ default:
+ t.Fatalf("ctx.Err is non-nil, but ctx.Done is not closed")
+ }
+ }
+}
diff --git a/go/src/crypto/crypto.go b/go/src/crypto/crypto.go
new file mode 100644
index 0000000000000000000000000000000000000000..0bf9ec834b7d910f23990e133b6caeea5c575012
--- /dev/null
+++ b/go/src/crypto/crypto.go
@@ -0,0 +1,273 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package crypto collects common cryptographic constants.
+package crypto
+
+import (
+ "hash"
+ "io"
+ "strconv"
+)
+
+// Hash identifies a cryptographic hash function that is implemented in another
+// package.
+type Hash uint
+
+// HashFunc simply returns the value of h so that [Hash] implements [SignerOpts].
+func (h Hash) HashFunc() Hash {
+ return h
+}
+
+func (h Hash) String() string {
+ switch h {
+ case MD4:
+ return "MD4"
+ case MD5:
+ return "MD5"
+ case SHA1:
+ return "SHA-1"
+ case SHA224:
+ return "SHA-224"
+ case SHA256:
+ return "SHA-256"
+ case SHA384:
+ return "SHA-384"
+ case SHA512:
+ return "SHA-512"
+ case MD5SHA1:
+ return "MD5+SHA1"
+ case RIPEMD160:
+ return "RIPEMD-160"
+ case SHA3_224:
+ return "SHA3-224"
+ case SHA3_256:
+ return "SHA3-256"
+ case SHA3_384:
+ return "SHA3-384"
+ case SHA3_512:
+ return "SHA3-512"
+ case SHA512_224:
+ return "SHA-512/224"
+ case SHA512_256:
+ return "SHA-512/256"
+ case BLAKE2s_256:
+ return "BLAKE2s-256"
+ case BLAKE2b_256:
+ return "BLAKE2b-256"
+ case BLAKE2b_384:
+ return "BLAKE2b-384"
+ case BLAKE2b_512:
+ return "BLAKE2b-512"
+ default:
+ return "unknown hash value " + strconv.Itoa(int(h))
+ }
+}
+
+const (
+ MD4 Hash = 1 + iota // import golang.org/x/crypto/md4
+ MD5 // import crypto/md5
+ SHA1 // import crypto/sha1
+ SHA224 // import crypto/sha256
+ SHA256 // import crypto/sha256
+ SHA384 // import crypto/sha512
+ SHA512 // import crypto/sha512
+ MD5SHA1 // no implementation; MD5+SHA1 used for TLS RSA
+ RIPEMD160 // import golang.org/x/crypto/ripemd160
+ SHA3_224 // import crypto/sha3
+ SHA3_256 // import crypto/sha3
+ SHA3_384 // import crypto/sha3
+ SHA3_512 // import crypto/sha3
+ SHA512_224 // import crypto/sha512
+ SHA512_256 // import crypto/sha512
+ BLAKE2s_256 // import golang.org/x/crypto/blake2s
+ BLAKE2b_256 // import golang.org/x/crypto/blake2b
+ BLAKE2b_384 // import golang.org/x/crypto/blake2b
+ BLAKE2b_512 // import golang.org/x/crypto/blake2b
+ maxHash
+)
+
+var digestSizes = []uint8{
+ MD4: 16,
+ MD5: 16,
+ SHA1: 20,
+ SHA224: 28,
+ SHA256: 32,
+ SHA384: 48,
+ SHA512: 64,
+ SHA512_224: 28,
+ SHA512_256: 32,
+ SHA3_224: 28,
+ SHA3_256: 32,
+ SHA3_384: 48,
+ SHA3_512: 64,
+ MD5SHA1: 36,
+ RIPEMD160: 20,
+ BLAKE2s_256: 32,
+ BLAKE2b_256: 32,
+ BLAKE2b_384: 48,
+ BLAKE2b_512: 64,
+}
+
+// Size returns the length, in bytes, of a digest resulting from the given hash
+// function. It doesn't require that the hash function in question be linked
+// into the program.
+func (h Hash) Size() int {
+ if h > 0 && h < maxHash {
+ return int(digestSizes[h])
+ }
+ panic("crypto: Size of unknown hash function")
+}
+
+var hashes = make([]func() hash.Hash, maxHash)
+
+// New returns a new hash.Hash calculating the given hash function. New panics
+// if the hash function is not linked into the binary.
+func (h Hash) New() hash.Hash {
+ if h > 0 && h < maxHash {
+ f := hashes[h]
+ if f != nil {
+ return f()
+ }
+ }
+ panic("crypto: requested hash function #" + strconv.Itoa(int(h)) + " is unavailable")
+}
+
+// Available reports whether the given hash function is linked into the binary.
+func (h Hash) Available() bool {
+ return h < maxHash && hashes[h] != nil
+}
+
+// RegisterHash registers a function that returns a new instance of the given
+// hash function. This is intended to be called from the init function in
+// packages that implement hash functions.
+func RegisterHash(h Hash, f func() hash.Hash) {
+ if h >= maxHash {
+ panic("crypto: RegisterHash of unknown hash function")
+ }
+ hashes[h] = f
+}
+
+// PublicKey represents a public key using an unspecified algorithm.
+//
+// Although this type is an empty interface for backwards compatibility reasons,
+// all public key types in the standard library implement the following interface
+//
+// interface{
+// Equal(x crypto.PublicKey) bool
+// }
+//
+// which can be used for increased type safety within applications.
+type PublicKey any
+
+// PrivateKey represents a private key using an unspecified algorithm.
+//
+// Although this type is an empty interface for backwards compatibility reasons,
+// all private key types in the standard library implement the following interface
+//
+// interface{
+// Public() crypto.PublicKey
+// Equal(x crypto.PrivateKey) bool
+// }
+//
+// as well as purpose-specific interfaces such as [Signer] and [Decrypter], which
+// can be used for increased type safety within applications.
+type PrivateKey any
+
+// Signer is an interface for an opaque private key that can be used for
+// signing operations. For example, an RSA key kept in a hardware module.
+type Signer interface {
+ // Public returns the public key corresponding to the opaque,
+ // private key.
+ Public() PublicKey
+
+ // Sign signs digest with the private key, possibly using entropy from
+ // rand. For an RSA key, the resulting signature should be either a
+ // PKCS #1 v1.5 or PSS signature (as indicated by opts). For an (EC)DSA
+ // key, it should be a DER-serialised, ASN.1 signature structure.
+ //
+ // Hash implements the SignerOpts interface and, in most cases, one can
+ // simply pass in the hash function used as opts. Sign may also attempt
+ // to type assert opts to other types in order to obtain algorithm
+ // specific values. See the documentation in each package for details.
+ //
+ // Note that when a signature of a hash of a larger message is needed,
+ // the caller is responsible for hashing the larger message and passing
+ // the hash (as digest) and the hash function (as opts) to Sign.
+ Sign(rand io.Reader, digest []byte, opts SignerOpts) (signature []byte, err error)
+}
+
+// MessageSigner is an interface for an opaque private key that can be used for
+// signing operations where the message is not pre-hashed by the caller.
+// It is a superset of the Signer interface so that it can be passed to APIs
+// which accept Signer, which may try to do an interface upgrade.
+//
+// MessageSigner.SignMessage and MessageSigner.Sign should produce the same
+// result given the same opts. In particular, MessageSigner.SignMessage should
+// only accept a zero opts.HashFunc if the Signer would also accept messages
+// which are not pre-hashed.
+//
+// Implementations which do not provide the pre-hashed Sign API should implement
+// Signer.Sign by always returning an error.
+type MessageSigner interface {
+ Signer
+ SignMessage(rand io.Reader, msg []byte, opts SignerOpts) (signature []byte, err error)
+}
+
+// SignerOpts contains options for signing with a [Signer].
+type SignerOpts interface {
+ // HashFunc returns an identifier for the hash function used to produce
+ // the message passed to Signer.Sign, or else zero to indicate that no
+ // hashing was done.
+ HashFunc() Hash
+}
+
+// Decrypter is an interface for an opaque private key that can be used for
+// asymmetric decryption operations. An example would be an RSA key
+// kept in a hardware module.
+type Decrypter interface {
+ // Public returns the public key corresponding to the opaque,
+ // private key.
+ Public() PublicKey
+
+ // Decrypt decrypts msg. The opts argument should be appropriate for
+ // the primitive used. See the documentation in each implementation for
+ // details.
+ Decrypt(rand io.Reader, msg []byte, opts DecrypterOpts) (plaintext []byte, err error)
+}
+
+type DecrypterOpts any
+
+// SignMessage signs msg with signer. If signer implements [MessageSigner],
+// [MessageSigner.SignMessage] is called directly. Otherwise, msg is hashed
+// with opts.HashFunc() and signed with [Signer.Sign].
+func SignMessage(signer Signer, rand io.Reader, msg []byte, opts SignerOpts) (signature []byte, err error) {
+ if ms, ok := signer.(MessageSigner); ok {
+ return ms.SignMessage(rand, msg, opts)
+ }
+ if opts.HashFunc() != 0 {
+ h := opts.HashFunc().New()
+ h.Write(msg)
+ msg = h.Sum(nil)
+ }
+ return signer.Sign(rand, msg, opts)
+}
+
+// Decapsulator is an interface for an opaque private KEM key that can be used for
+// decapsulation operations. For example, an ML-KEM key kept in a hardware module.
+//
+// It is implemented, for example, by [crypto/mlkem.DecapsulationKey768].
+type Decapsulator interface {
+ Encapsulator() Encapsulator
+ Decapsulate(ciphertext []byte) (sharedKey []byte, err error)
+}
+
+// Encapsulator is an interface for a public KEM key that can be used for
+// encapsulation operations.
+//
+// It is implemented, for example, by [crypto/mlkem.EncapsulationKey768].
+type Encapsulator interface {
+ Bytes() []byte
+ Encapsulate() (sharedKey, ciphertext []byte)
+}
diff --git a/go/src/crypto/crypto_test.go b/go/src/crypto/crypto_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..66babcc2fb0d05bf7f4a985cb5ba9256239783f1
--- /dev/null
+++ b/go/src/crypto/crypto_test.go
@@ -0,0 +1,143 @@
+// Copyright 2025 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package crypto_test
+
+import (
+ "bytes"
+ "crypto"
+ "crypto/rand"
+ "crypto/rsa"
+ "crypto/x509"
+ "encoding/pem"
+ "errors"
+ "internal/testenv"
+ "io"
+ "io/fs"
+ "os"
+ "path/filepath"
+ "regexp"
+ "strings"
+ "testing"
+)
+
+type messageSignerOnly struct {
+ k *rsa.PrivateKey
+}
+
+func (s *messageSignerOnly) Public() crypto.PublicKey {
+ return s.k.Public()
+}
+
+func (s *messageSignerOnly) Sign(_ io.Reader, _ []byte, _ crypto.SignerOpts) ([]byte, error) {
+ return nil, errors.New("unimplemented")
+}
+
+func (s *messageSignerOnly) SignMessage(rand io.Reader, msg []byte, opts crypto.SignerOpts) ([]byte, error) {
+ h := opts.HashFunc().New()
+ h.Write(msg)
+ digest := h.Sum(nil)
+ return s.k.Sign(rand, digest, opts)
+}
+
+func TestSignMessage(t *testing.T) {
+ block, _ := pem.Decode([]byte(strings.ReplaceAll(
+ `-----BEGIN RSA TESTING KEY-----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+-----END RSA TESTING KEY-----`, "TESTING KEY", "PRIVATE KEY")))
+ k, _ := x509.ParsePKCS1PrivateKey(block.Bytes)
+
+ msg := []byte("hello :)")
+
+ h := crypto.SHA256.New()
+ h.Write(msg)
+ digest := h.Sum(nil)
+
+ sig, err := crypto.SignMessage(k, rand.Reader, msg, &rsa.PSSOptions{Hash: crypto.SHA256})
+ if err != nil {
+ t.Fatalf("SignMessage failed with Signer: %s", err)
+ }
+ if err := rsa.VerifyPSS(&k.PublicKey, crypto.SHA256, digest, sig, nil); err != nil {
+ t.Errorf("VerifyPSS failed for Signer signature: %s", err)
+ }
+
+ sig, err = crypto.SignMessage(&messageSignerOnly{k}, rand.Reader, msg, &rsa.PSSOptions{Hash: crypto.SHA256})
+ if err != nil {
+ t.Fatalf("SignMessage failed with MessageSigner: %s", err)
+ }
+ if err := rsa.VerifyPSS(&k.PublicKey, crypto.SHA256, digest, sig, nil); err != nil {
+ t.Errorf("VerifyPSS failed for MessageSigner signature: %s", err)
+ }
+}
+
+func TestDisallowedAssemblyInstructions(t *testing.T) {
+ // This test enforces the cryptography assembly policy rule that we do not
+ // use BYTE or WORD instructions, since these instructions can obscure what
+ // the assembly is actually doing. If we do not support specific
+ // instructions in the assembler, we should not be using them until we do.
+ //
+ // Instead of using the output of the 'go tool asm' tool, we take the simple
+ // approach and just search the text of .s files for usage of BYTE and WORD.
+ // We do this because the assembler itself will sometimes insert WORD
+ // instructions for things like function preambles etc.
+
+ boringSigPath := filepath.Join("internal", "boring", "sig")
+
+ matcher, err := regexp.Compile(`(^|;)\s(BYTE|WORD)\s`)
+ if err != nil {
+ t.Fatal(err)
+ }
+ if err := filepath.WalkDir(filepath.Join(testenv.GOROOT(t), "src/crypto"), func(path string, d fs.DirEntry, err error) error {
+ if err != nil {
+ t.Fatal(err)
+ }
+ if d.IsDir() || !strings.HasSuffix(path, ".s") {
+ return nil
+ }
+ if strings.Contains(path, boringSigPath) {
+ return nil
+ }
+
+ f, err := os.ReadFile(path)
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ i := 1
+ for line := range bytes.Lines(f) {
+ if matcher.Match(line) {
+ t.Errorf("%s:%d assembly contains BYTE or WORD instruction (%q)", path, i, string(line))
+ }
+ i++
+ }
+
+ return nil
+ }); err != nil {
+ t.Fatal(err)
+ }
+}
diff --git a/go/src/crypto/issue21104_test.go b/go/src/crypto/issue21104_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..466208879991e1a12ecf92d34b53d71885ed1b08
--- /dev/null
+++ b/go/src/crypto/issue21104_test.go
@@ -0,0 +1,61 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package crypto_test
+
+import (
+ "crypto/aes"
+ "crypto/cipher"
+ "crypto/rc4"
+ "testing"
+)
+
+func TestRC4OutOfBoundsWrite(t *testing.T) {
+ // This cipherText is encrypted "0123456789"
+ cipherText := []byte{238, 41, 187, 114, 151, 2, 107, 13, 178, 63}
+ cipher, err := rc4.NewCipher([]byte{0})
+ if err != nil {
+ panic(err)
+ }
+ test(t, "RC4", cipherText, cipher.XORKeyStream)
+}
+func TestCTROutOfBoundsWrite(t *testing.T) {
+ testBlock(t, "CTR", cipher.NewCTR)
+}
+func TestOFBOutOfBoundsWrite(t *testing.T) {
+ testBlock(t, "OFB", cipher.NewOFB)
+}
+func TestCFBEncryptOutOfBoundsWrite(t *testing.T) {
+ testBlock(t, "CFB Encrypt", cipher.NewCFBEncrypter)
+}
+func TestCFBDecryptOutOfBoundsWrite(t *testing.T) {
+ testBlock(t, "CFB Decrypt", cipher.NewCFBDecrypter)
+}
+func testBlock(t *testing.T, name string, newCipher func(cipher.Block, []byte) cipher.Stream) {
+ // This cipherText is encrypted "0123456789"
+ cipherText := []byte{86, 216, 121, 231, 219, 191, 26, 12, 176, 117}
+ var iv, key [16]byte
+ block, err := aes.NewCipher(key[:])
+ if err != nil {
+ panic(err)
+ }
+ stream := newCipher(block, iv[:])
+ test(t, name, cipherText, stream.XORKeyStream)
+}
+func test(t *testing.T, name string, cipherText []byte, xor func([]byte, []byte)) {
+ want := "abcdefghij"
+ plainText := []byte(want)
+ shorterLen := len(cipherText) / 2
+ defer func() {
+ err := recover()
+ if err == nil {
+ t.Errorf("%v XORKeyStream expected to panic on len(dst) < len(src), but didn't", name)
+ }
+ const plain = "0123456789"
+ if plainText[shorterLen] == plain[shorterLen] {
+ t.Errorf("%v XORKeyStream did out of bounds write, want %v, got %v", name, want, string(plainText))
+ }
+ }()
+ xor(plainText[:shorterLen], cipherText)
+}
diff --git a/go/src/crypto/purego_test.go b/go/src/crypto/purego_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..ebc9110cecee82bcaea66d2a95987f309a36e633
--- /dev/null
+++ b/go/src/crypto/purego_test.go
@@ -0,0 +1,67 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package crypto_test
+
+import (
+ "go/build"
+ "internal/testenv"
+ "log"
+ "os"
+ "strings"
+ "testing"
+)
+
+// TestPureGoTag checks that when built with the purego build tag, crypto
+// packages don't require any assembly. This is used by alternative compilers
+// such as TinyGo. See also the "crypto/...:purego" test in cmd/dist, which
+// ensures the packages build correctly.
+func TestPureGoTag(t *testing.T) {
+ cmd := testenv.Command(t, testenv.GoToolPath(t), "list", "-e", "crypto/...", "math/big")
+ cmd = testenv.CleanCmdEnv(cmd)
+ cmd.Env = append(cmd.Environ(), "GOOS=linux", "GOFIPS140=off")
+ cmd.Stderr = os.Stderr
+ out, err := cmd.Output()
+ if err != nil {
+ log.Fatalf("loading package list: %v\n%s", err, out)
+ }
+ pkgs := strings.Split(strings.TrimSpace(string(out)), "\n")
+
+ cmd = testenv.Command(t, testenv.GoToolPath(t), "tool", "dist", "list")
+ cmd.Stderr = os.Stderr
+ out, err = testenv.CleanCmdEnv(cmd).Output()
+ if err != nil {
+ log.Fatalf("loading architecture list: %v\n%s", err, out)
+ }
+ allGOARCH := make(map[string]bool)
+ for _, pair := range strings.Split(strings.TrimSpace(string(out)), "\n") {
+ GOARCH := strings.Split(pair, "/")[1]
+ allGOARCH[GOARCH] = true
+ }
+
+ for _, pkgName := range pkgs {
+ if strings.Contains(pkgName, "/boring") {
+ continue
+ }
+
+ for GOARCH := range allGOARCH {
+ context := build.Context{
+ GOOS: "linux", // darwin has custom assembly
+ GOARCH: GOARCH,
+ GOROOT: testenv.GOROOT(t),
+ Compiler: build.Default.Compiler,
+ BuildTags: []string{"purego", "math_big_pure_go"},
+ }
+
+ pkg, err := context.Import(pkgName, "", 0)
+ if err != nil {
+ t.Fatal(err)
+ }
+ if len(pkg.SFiles) == 0 {
+ continue
+ }
+ t.Errorf("package %s has purego assembly files on %s: %v", pkgName, GOARCH, pkg.SFiles)
+ }
+ }
+}
diff --git a/go/src/embed/embed.go b/go/src/embed/embed.go
new file mode 100644
index 0000000000000000000000000000000000000000..4d5e418c9024b338171a204839023e3a0d2d6771
--- /dev/null
+++ b/go/src/embed/embed.go
@@ -0,0 +1,436 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package embed provides access to files embedded in the running Go program.
+//
+// Go source files that import "embed" can use the //go:embed directive
+// to initialize a variable of type string, []byte, or [FS] with the contents of
+// files read from the package directory or subdirectories at compile time.
+//
+// For example, here are three ways to embed a file named hello.txt
+// and then print its contents at run time.
+//
+// Embedding one file into a string:
+//
+// import _ "embed"
+//
+// //go:embed hello.txt
+// var s string
+// print(s)
+//
+// Embedding one file into a slice of bytes:
+//
+// import _ "embed"
+//
+// //go:embed hello.txt
+// var b []byte
+// print(string(b))
+//
+// Embedded one or more files into a file system:
+//
+// import "embed"
+//
+// //go:embed hello.txt
+// var f embed.FS
+// data, _ := f.ReadFile("hello.txt")
+// print(string(data))
+//
+// # Directives
+//
+// A //go:embed directive above a variable declaration specifies which files to embed,
+// using one or more path.Match patterns.
+//
+// The directive must immediately precede a line containing the declaration of a single variable.
+// Only blank lines and ‘//’ line comments are permitted between the directive and the declaration.
+//
+// The type of the variable must be a string type, or a slice of a byte type,
+// or [FS] (or an alias of [FS]).
+//
+// For example:
+//
+// package server
+//
+// import "embed"
+//
+// // content holds our static web server content.
+// //go:embed image/* template/*
+// //go:embed html/index.html
+// var content embed.FS
+//
+// The Go build system will recognize the directives and arrange for the declared variable
+// (in the example above, content) to be populated with the matching files from the file system.
+//
+// The //go:embed directive accepts multiple space-separated patterns for
+// brevity, but it can also be repeated, to avoid very long lines when there are
+// many patterns. The patterns are interpreted relative to the package directory
+// containing the source file. The path separator is a forward slash, even on
+// Windows systems. Patterns may not contain ‘.’ or ‘..’ or empty path elements,
+// nor may they begin or end with a slash. To match everything in the current
+// directory, use ‘*’ instead of ‘.’. To allow for naming files with spaces in
+// their names, patterns can be written as Go double-quoted or back-quoted
+// string literals.
+//
+// If a pattern names a directory, all files in the subtree rooted at that directory are
+// embedded (recursively), except that files with names beginning with ‘.’ or ‘_’
+// are excluded. So the variable in the above example is almost equivalent to:
+//
+// // content is our static web server content.
+// //go:embed image template html/index.html
+// var content embed.FS
+//
+// The difference is that ‘image/*’ embeds ‘image/.tempfile’ while ‘image’ does not.
+// Neither embeds ‘image/dir/.tempfile’.
+//
+// If a pattern begins with the prefix ‘all:’, then the rule for walking directories is changed
+// to include those files beginning with ‘.’ or ‘_’. For example, ‘all:image’ embeds
+// both ‘image/.tempfile’ and ‘image/dir/.tempfile’.
+//
+// The //go:embed directive can be used with both exported and unexported variables,
+// depending on whether the package wants to make the data available to other packages.
+// It can only be used with variables at package scope, not with local variables.
+//
+// Patterns must not match files outside the package's module, such as ‘.git/*’, symbolic links,
+// 'vendor/', or any directories containing go.mod (these are separate modules).
+// Patterns must not match files whose names include the special punctuation characters " * < > ? ` ' | / \ and :.
+// Matches for empty directories are ignored. After that, each pattern in a //go:embed line
+// must match at least one file or non-empty directory.
+//
+// If any patterns are invalid or have invalid matches, the build will fail.
+//
+// # Strings and Bytes
+//
+// The //go:embed line for a variable of type string or []byte can have only a single pattern,
+// and that pattern can match only a single file. The string or []byte is initialized with
+// the contents of that file.
+//
+// The //go:embed directive requires importing "embed", even when using a string or []byte.
+// In source files that don't refer to [embed.FS], use a blank import (import _ "embed").
+//
+// # File Systems
+//
+// For embedding a single file, a variable of type string or []byte is often best.
+// The [FS] type enables embedding a tree of files, such as a directory of static
+// web server content, as in the example above.
+//
+// FS implements the [io/fs] package's [FS] interface, so it can be used with any package that
+// understands file systems, including [net/http], [text/template], and [html/template].
+//
+// For example, given the content variable in the example above, we can write:
+//
+// http.Handle("/static/", http.StripPrefix("/static/", http.FileServer(http.FS(content))))
+//
+// template.ParseFS(content, "*.tmpl")
+//
+// # Tools
+//
+// To support tools that analyze Go packages, the patterns found in //go:embed lines
+// are available in “go list” output. See the EmbedPatterns, TestEmbedPatterns,
+// and XTestEmbedPatterns fields in the “go help list” output.
+package embed
+
+import (
+ "errors"
+ "internal/bytealg"
+ "internal/stringslite"
+ "io"
+ "io/fs"
+ "time"
+)
+
+// An FS is a read-only collection of files, usually initialized with a //go:embed directive.
+// When declared without a //go:embed directive, an FS is an empty file system.
+//
+// An FS is a read-only value, so it is safe to use from multiple goroutines
+// simultaneously and also safe to assign values of type FS to each other.
+//
+// FS implements fs.FS, so it can be used with any package that understands
+// file system interfaces, including net/http, text/template, and html/template.
+//
+// See the package documentation for more details about initializing an FS.
+type FS struct {
+ // The compiler knows the layout of this struct.
+ // See cmd/compile/internal/staticdata's WriteEmbed.
+ //
+ // The files list is sorted by name but not by simple string comparison.
+ // Instead, each file's name takes the form "dir/elem" or "dir/elem/".
+ // The optional trailing slash indicates that the file is itself a directory.
+ // The files list is sorted first by dir (if dir is missing, it is taken to be ".")
+ // and then by base, so this list of files:
+ //
+ // p
+ // q/
+ // q/r
+ // q/s/
+ // q/s/t
+ // q/s/u
+ // q/v
+ // w
+ //
+ // is actually sorted as:
+ //
+ // p # dir=. elem=p
+ // q/ # dir=. elem=q
+ // w # dir=. elem=w
+ // q/r # dir=q elem=r
+ // q/s/ # dir=q elem=s
+ // q/v # dir=q elem=v
+ // q/s/t # dir=q/s elem=t
+ // q/s/u # dir=q/s elem=u
+ //
+ // This order brings directory contents together in contiguous sections
+ // of the list, allowing a directory read to use binary search to find
+ // the relevant sequence of entries.
+ files *[]file
+}
+
+// split splits the name into dir and elem as described in the
+// comment in the FS struct above. isDir reports whether the
+// final trailing slash was present, indicating that name is a directory.
+func split(name string) (dir, elem string, isDir bool) {
+ name, isDir = stringslite.CutSuffix(name, "/")
+ i := bytealg.LastIndexByteString(name, '/')
+ if i < 0 {
+ return ".", name, isDir
+ }
+ return name[:i], name[i+1:], isDir
+}
+
+var (
+ _ fs.ReadDirFS = FS{}
+ _ fs.ReadFileFS = FS{}
+)
+
+// A file is a single file in the FS.
+// It implements fs.FileInfo and fs.DirEntry.
+type file struct {
+ // The compiler knows the layout of this struct.
+ // See cmd/compile/internal/staticdata's WriteEmbed.
+ name string
+ data string
+ hash [16]byte // truncated SHA256 hash
+}
+
+var (
+ _ fs.FileInfo = (*file)(nil)
+ _ fs.DirEntry = (*file)(nil)
+)
+
+func (f *file) Name() string { _, elem, _ := split(f.name); return elem }
+func (f *file) Size() int64 { return int64(len(f.data)) }
+func (f *file) ModTime() time.Time { return time.Time{} }
+func (f *file) IsDir() bool { _, _, isDir := split(f.name); return isDir }
+func (f *file) Sys() any { return nil }
+func (f *file) Type() fs.FileMode { return f.Mode().Type() }
+func (f *file) Info() (fs.FileInfo, error) { return f, nil }
+
+func (f *file) Mode() fs.FileMode {
+ if f.IsDir() {
+ return fs.ModeDir | 0555
+ }
+ return 0444
+}
+
+func (f *file) String() string {
+ return fs.FormatFileInfo(f)
+}
+
+// dotFile is a file for the root directory,
+// which is omitted from the files list in a FS.
+var dotFile = &file{name: "./"}
+
+// lookup returns the named file, or nil if it is not present.
+func (f FS) lookup(name string) *file {
+ if !fs.ValidPath(name) {
+ // The compiler should never emit a file with an invalid name,
+ // so this check is not strictly necessary (if name is invalid,
+ // we shouldn't find a match below), but it's a good backstop anyway.
+ return nil
+ }
+ if name == "." {
+ return dotFile
+ }
+ if f.files == nil {
+ return nil
+ }
+
+ // Binary search to find where name would be in the list,
+ // and then check if name is at that position.
+ dir, elem, _ := split(name)
+ files := *f.files
+ i := sortSearch(len(files), func(i int) bool {
+ idir, ielem, _ := split(files[i].name)
+ return idir > dir || idir == dir && ielem >= elem
+ })
+ if i < len(files) && stringslite.TrimSuffix(files[i].name, "/") == name {
+ return &files[i]
+ }
+ return nil
+}
+
+// readDir returns the list of files corresponding to the directory dir.
+func (f FS) readDir(dir string) []file {
+ if f.files == nil {
+ return nil
+ }
+ // Binary search to find where dir starts and ends in the list
+ // and then return that slice of the list.
+ files := *f.files
+ i := sortSearch(len(files), func(i int) bool {
+ idir, _, _ := split(files[i].name)
+ return idir >= dir
+ })
+ j := sortSearch(len(files), func(j int) bool {
+ jdir, _, _ := split(files[j].name)
+ return jdir > dir
+ })
+ return files[i:j]
+}
+
+// Open opens the named file for reading and returns it as an [fs.File].
+//
+// The returned file implements [io.Seeker] and [io.ReaderAt] when the file is not a directory.
+func (f FS) Open(name string) (fs.File, error) {
+ file := f.lookup(name)
+ if file == nil {
+ return nil, &fs.PathError{Op: "open", Path: name, Err: fs.ErrNotExist}
+ }
+ if file.IsDir() {
+ return &openDir{file, f.readDir(name), 0}, nil
+ }
+ return &openFile{file, 0}, nil
+}
+
+// ReadDir reads and returns the entire named directory.
+func (f FS) ReadDir(name string) ([]fs.DirEntry, error) {
+ file, err := f.Open(name)
+ if err != nil {
+ return nil, err
+ }
+ dir, ok := file.(*openDir)
+ if !ok {
+ return nil, &fs.PathError{Op: "read", Path: name, Err: errors.New("not a directory")}
+ }
+ list := make([]fs.DirEntry, len(dir.files))
+ for i := range list {
+ list[i] = &dir.files[i]
+ }
+ return list, nil
+}
+
+// ReadFile reads and returns the content of the named file.
+func (f FS) ReadFile(name string) ([]byte, error) {
+ file, err := f.Open(name)
+ if err != nil {
+ return nil, err
+ }
+ ofile, ok := file.(*openFile)
+ if !ok {
+ return nil, &fs.PathError{Op: "read", Path: name, Err: errors.New("is a directory")}
+ }
+ return []byte(ofile.f.data), nil
+}
+
+// An openFile is a regular file open for reading.
+type openFile struct {
+ f *file // the file itself
+ offset int64 // current read offset
+}
+
+var (
+ _ io.Seeker = (*openFile)(nil)
+ _ io.ReaderAt = (*openFile)(nil)
+)
+
+func (f *openFile) Close() error { return nil }
+func (f *openFile) Stat() (fs.FileInfo, error) { return f.f, nil }
+
+func (f *openFile) Read(b []byte) (int, error) {
+ if f.offset >= int64(len(f.f.data)) {
+ return 0, io.EOF
+ }
+ if f.offset < 0 {
+ return 0, &fs.PathError{Op: "read", Path: f.f.name, Err: fs.ErrInvalid}
+ }
+ n := copy(b, f.f.data[f.offset:])
+ f.offset += int64(n)
+ return n, nil
+}
+
+func (f *openFile) Seek(offset int64, whence int) (int64, error) {
+ switch whence {
+ case 0:
+ // offset += 0
+ case 1:
+ offset += f.offset
+ case 2:
+ offset += int64(len(f.f.data))
+ }
+ if offset < 0 || offset > int64(len(f.f.data)) {
+ return 0, &fs.PathError{Op: "seek", Path: f.f.name, Err: fs.ErrInvalid}
+ }
+ f.offset = offset
+ return offset, nil
+}
+
+func (f *openFile) ReadAt(b []byte, offset int64) (int, error) {
+ if offset < 0 || offset > int64(len(f.f.data)) {
+ return 0, &fs.PathError{Op: "read", Path: f.f.name, Err: fs.ErrInvalid}
+ }
+ n := copy(b, f.f.data[offset:])
+ if n < len(b) {
+ return n, io.EOF
+ }
+ return n, nil
+}
+
+// An openDir is a directory open for reading.
+type openDir struct {
+ f *file // the directory file itself
+ files []file // the directory contents
+ offset int // the read offset, an index into the files slice
+}
+
+func (d *openDir) Close() error { return nil }
+func (d *openDir) Stat() (fs.FileInfo, error) { return d.f, nil }
+
+func (d *openDir) Read([]byte) (int, error) {
+ return 0, &fs.PathError{Op: "read", Path: d.f.name, Err: errors.New("is a directory")}
+}
+
+func (d *openDir) ReadDir(count int) ([]fs.DirEntry, error) {
+ n := len(d.files) - d.offset
+ if n == 0 {
+ if count <= 0 {
+ return nil, nil
+ }
+ return nil, io.EOF
+ }
+ if count > 0 && n > count {
+ n = count
+ }
+ list := make([]fs.DirEntry, n)
+ for i := range list {
+ list[i] = &d.files[d.offset+i]
+ }
+ d.offset += n
+ return list, nil
+}
+
+// sortSearch is like sort.Search, avoiding an import.
+func sortSearch(n int, f func(int) bool) int {
+ // Define f(-1) == false and f(n) == true.
+ // Invariant: f(i-1) == false, f(j) == true.
+ i, j := 0, n
+ for i < j {
+ h := int(uint(i+j) >> 1) // avoid overflow when computing h
+ // i ≤ h < j
+ if !f(h) {
+ i = h + 1 // preserves f(i-1) == false
+ } else {
+ j = h // preserves f(j) == true
+ }
+ }
+ // i == j, f(i-1) == false, and f(j) (= f(i)) == true => answer is i.
+ return i
+}
diff --git a/go/src/embed/example_test.go b/go/src/embed/example_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..b92eb520092013f4c33e897701c99d0941aec9cb
--- /dev/null
+++ b/go/src/embed/example_test.go
@@ -0,0 +1,23 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package embed_test
+
+import (
+ "embed"
+ "log"
+ "net/http"
+)
+
+//go:embed internal/embedtest/testdata/*.txt
+var content embed.FS
+
+func Example() {
+ mux := http.NewServeMux()
+ mux.Handle("/", http.FileServer(http.FS(content)))
+ err := http.ListenAndServe(":8080", mux)
+ if err != nil {
+ log.Fatal(err)
+ }
+}
diff --git a/go/src/encoding/encoding.go b/go/src/encoding/encoding.go
new file mode 100644
index 0000000000000000000000000000000000000000..4d288b6d3b9b3e30444b634dd0403ea1245ffff2
--- /dev/null
+++ b/go/src/encoding/encoding.go
@@ -0,0 +1,78 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package encoding defines interfaces shared by other packages that
+// convert data to and from byte-level and textual representations.
+// Packages that check for these interfaces include encoding/gob,
+// encoding/json, and encoding/xml. As a result, implementing an
+// interface once can make a type useful in multiple encodings.
+// Standard types that implement these interfaces include time.Time and net.IP.
+// The interfaces come in pairs that produce and consume encoded data.
+//
+// Adding encoding/decoding methods to existing types may constitute a breaking change,
+// as they can be used for serialization in communicating with programs
+// written with different library versions.
+// The policy for packages maintained by the Go project is to only allow
+// the addition of marshaling functions if no existing, reasonable marshaling exists.
+package encoding
+
+// BinaryMarshaler is the interface implemented by an object that can
+// marshal itself into a binary form.
+//
+// MarshalBinary encodes the receiver into a binary form and returns the result.
+type BinaryMarshaler interface {
+ MarshalBinary() (data []byte, err error)
+}
+
+// BinaryUnmarshaler is the interface implemented by an object that can
+// unmarshal a binary representation of itself.
+//
+// UnmarshalBinary must be able to decode the form generated by MarshalBinary.
+// UnmarshalBinary must copy the data if it wishes to retain the data
+// after returning.
+type BinaryUnmarshaler interface {
+ UnmarshalBinary(data []byte) error
+}
+
+// BinaryAppender is the interface implemented by an object
+// that can append the binary representation of itself.
+// If a type implements both [BinaryAppender] and [BinaryMarshaler],
+// then v.MarshalBinary() must be semantically identical to v.AppendBinary(nil).
+type BinaryAppender interface {
+ // AppendBinary appends the binary representation of itself to the end of b
+ // (allocating a larger slice if necessary) and returns the updated slice.
+ //
+ // Implementations must not retain b, nor mutate any bytes within b[:len(b)].
+ AppendBinary(b []byte) ([]byte, error)
+}
+
+// TextMarshaler is the interface implemented by an object that can
+// marshal itself into a textual form.
+//
+// MarshalText encodes the receiver into UTF-8-encoded text and returns the result.
+type TextMarshaler interface {
+ MarshalText() (text []byte, err error)
+}
+
+// TextUnmarshaler is the interface implemented by an object that can
+// unmarshal a textual representation of itself.
+//
+// UnmarshalText must be able to decode the form generated by MarshalText.
+// UnmarshalText must copy the text if it wishes to retain the text
+// after returning.
+type TextUnmarshaler interface {
+ UnmarshalText(text []byte) error
+}
+
+// TextAppender is the interface implemented by an object
+// that can append the textual representation of itself.
+// If a type implements both [TextAppender] and [TextMarshaler],
+// then v.MarshalText() must be semantically identical to v.AppendText(nil).
+type TextAppender interface {
+ // AppendText appends the textual representation of itself to the end of b
+ // (allocating a larger slice if necessary) and returns the updated slice.
+ //
+ // Implementations must not retain b, nor mutate any bytes within b[:len(b)].
+ AppendText(b []byte) ([]byte, error)
+}
diff --git a/go/src/errors/errors.go b/go/src/errors/errors.go
new file mode 100644
index 0000000000000000000000000000000000000000..8b926cfe148c448696750baa12b4ce175d4dc033
--- /dev/null
+++ b/go/src/errors/errors.go
@@ -0,0 +1,90 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package errors implements functions to manipulate errors.
+//
+// The [New] function creates errors whose only content is a text message.
+//
+// An error e wraps another error if e's type has one of the methods
+//
+// Unwrap() error
+// Unwrap() []error
+//
+// If e.Unwrap() returns a non-nil error w or a slice containing w,
+// then we say that e wraps w. A nil error returned from e.Unwrap()
+// indicates that e does not wrap any error. It is invalid for an
+// Unwrap method to return an []error containing a nil error value.
+//
+// An easy way to create wrapped errors is to call [fmt.Errorf] and apply
+// the %w verb to the error argument:
+//
+// wrapsErr := fmt.Errorf("... %w ...", ..., err, ...)
+//
+// Successive unwrapping of an error creates a tree. The [Is] and [As]
+// functions inspect an error's tree by examining first the error
+// itself followed by the tree of each of its children in turn
+// (pre-order, depth-first traversal).
+//
+// See https://go.dev/blog/go1.13-errors for a deeper discussion of the
+// philosophy of wrapping and when to wrap.
+//
+// [Is] examines the tree of its first argument looking for an error that
+// matches the second. It reports whether it finds a match. It should be
+// used in preference to simple equality checks:
+//
+// if errors.Is(err, fs.ErrExist)
+//
+// is preferable to
+//
+// if err == fs.ErrExist
+//
+// because the former will succeed if err wraps [io/fs.ErrExist].
+//
+// [AsType] examines the tree of its argument looking for an error whose
+// type matches its type argument. If it succeeds, it returns the
+// corresponding value of that type and true. Otherwise, it returns the
+// zero value of that type and false. The form
+//
+// if perr, ok := errors.AsType[*fs.PathError](err); ok {
+// fmt.Println(perr.Path)
+// }
+//
+// is preferable to
+//
+// if perr, ok := err.(*fs.PathError); ok {
+// fmt.Println(perr.Path)
+// }
+//
+// because the former will succeed if err wraps an [*io/fs.PathError].
+package errors
+
+// New returns an error that formats as the given text.
+// Each call to New returns a distinct error value even if the text is identical.
+func New(text string) error {
+ return &errorString{text}
+}
+
+// errorString is a trivial implementation of error.
+type errorString struct {
+ s string
+}
+
+func (e *errorString) Error() string {
+ return e.s
+}
+
+// ErrUnsupported indicates that a requested operation cannot be performed,
+// because it is unsupported. For example, a call to [os.Link] when using a
+// file system that does not support hard links.
+//
+// Functions and methods should not return this error but should instead
+// return an error including appropriate context that satisfies
+//
+// errors.Is(err, errors.ErrUnsupported)
+//
+// either by directly wrapping ErrUnsupported or by implementing an [Is] method.
+//
+// Functions and methods should document the cases in which an error
+// wrapping this will be returned.
+var ErrUnsupported = New("unsupported operation")
diff --git a/go/src/errors/errors_test.go b/go/src/errors/errors_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..08ed54e041cf03ab83ffe9146c6f08c0cb5daf05
--- /dev/null
+++ b/go/src/errors/errors_test.go
@@ -0,0 +1,33 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package errors_test
+
+import (
+ "errors"
+ "testing"
+)
+
+func TestNewEqual(t *testing.T) {
+ // Different allocations should not be equal.
+ if errors.New("abc") == errors.New("abc") {
+ t.Errorf(`New("abc") == New("abc")`)
+ }
+ if errors.New("abc") == errors.New("xyz") {
+ t.Errorf(`New("abc") == New("xyz")`)
+ }
+
+ // Same allocation should be equal to itself (not crash).
+ err := errors.New("jkl")
+ if err != err {
+ t.Errorf(`err != err`)
+ }
+}
+
+func TestErrorMethod(t *testing.T) {
+ err := errors.New("abc")
+ if err.Error() != "abc" {
+ t.Errorf(`New("abc").Error() = %q, want %q`, err.Error(), "abc")
+ }
+}
diff --git a/go/src/errors/example_test.go b/go/src/errors/example_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..298612c4eac92c3827c8f70ab68df93d48f79941
--- /dev/null
+++ b/go/src/errors/example_test.go
@@ -0,0 +1,238 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package errors_test
+
+import (
+ "errors"
+ "fmt"
+ "io/fs"
+ "os"
+ "time"
+)
+
+// MyError is an error implementation that includes a time and message.
+type MyError struct {
+ When time.Time
+ What string
+}
+
+func (e MyError) Error() string {
+ return fmt.Sprintf("%v: %v", e.When, e.What)
+}
+
+func oops() error {
+ return MyError{
+ time.Date(1989, 3, 15, 22, 30, 0, 0, time.UTC),
+ "the file system has gone away",
+ }
+}
+
+func Example() {
+ if err := oops(); err != nil {
+ fmt.Println(err)
+ }
+ // Output: 1989-03-15 22:30:00 +0000 UTC: the file system has gone away
+}
+
+func ExampleNew() {
+ err := errors.New("emit macho dwarf: elf header corrupted")
+ if err != nil {
+ fmt.Print(err)
+ }
+ // Output: emit macho dwarf: elf header corrupted
+}
+
+func OopsNew() error {
+ return errors.New("an error")
+}
+
+var ErrSentinel = errors.New("an error")
+
+func OopsSentinel() error {
+ return ErrSentinel
+}
+
+// Each call to [errors.New] returns an unique instance of the error,
+// even if the arguments are the same. To match against errors
+// created by [errors.New], declare a sentinel error and reuse it.
+func ExampleNew_unique() {
+ err1 := OopsNew()
+ err2 := OopsNew()
+ fmt.Println("Errors using distinct errors.New calls:")
+ fmt.Printf("Is(%q, %q) = %v\n", err1, err2, errors.Is(err1, err2))
+
+ err3 := OopsSentinel()
+ err4 := OopsSentinel()
+ fmt.Println()
+ fmt.Println("Errors using a sentinel error:")
+ fmt.Printf("Is(%q, %q) = %v\n", err3, err4, errors.Is(err3, err4))
+
+ // Output:
+ // Errors using distinct errors.New calls:
+ // Is("an error", "an error") = false
+ //
+ // Errors using a sentinel error:
+ // Is("an error", "an error") = true
+}
+
+// The fmt package's Errorf function lets us use the package's formatting
+// features to create descriptive error messages.
+func ExampleNew_errorf() {
+ const name, id = "bimmler", 17
+ err := fmt.Errorf("user %q (id %d) not found", name, id)
+ if err != nil {
+ fmt.Print(err)
+ }
+ // Output: user "bimmler" (id 17) not found
+}
+
+func ExampleJoin() {
+ err1 := errors.New("err1")
+ err2 := errors.New("err2")
+ err := errors.Join(err1, err2)
+ fmt.Println(err)
+ if errors.Is(err, err1) {
+ fmt.Println("err is err1")
+ }
+ if errors.Is(err, err2) {
+ fmt.Println("err is err2")
+ }
+ fmt.Println(err.(interface{ Unwrap() []error }).Unwrap())
+ // Output:
+ // err1
+ // err2
+ // err is err1
+ // err is err2
+ // [err1 err2]
+}
+
+func ExampleIs() {
+ if _, err := os.Open("non-existing"); err != nil {
+ if errors.Is(err, fs.ErrNotExist) {
+ fmt.Println("file does not exist")
+ } else {
+ fmt.Println(err)
+ }
+ }
+
+ // Output:
+ // file does not exist
+}
+
+type MyIsError struct {
+ err string
+}
+
+func (e MyIsError) Error() string {
+ return e.err
+}
+func (e MyIsError) Is(err error) bool {
+ return err == fs.ErrPermission
+}
+
+// Custom errors can implement a method "Is(error) bool" to match other error values,
+// overriding the default matching of [errors.Is].
+func ExampleIs_custom_match() {
+ var err error = MyIsError{"an error"}
+ fmt.Println("Error equals fs.ErrPermission:", err == fs.ErrPermission)
+ fmt.Println("Error is fs.ErrPermission:", errors.Is(err, fs.ErrPermission))
+
+ // Output:
+ // Error equals fs.ErrPermission: false
+ // Error is fs.ErrPermission: true
+}
+
+func ExampleAs() {
+ if _, err := os.Open("non-existing"); err != nil {
+ var pathError *fs.PathError
+ if errors.As(err, &pathError) {
+ fmt.Println("Failed at path:", pathError.Path)
+ } else {
+ fmt.Println(err)
+ }
+ }
+
+ // Output:
+ // Failed at path: non-existing
+}
+
+func ExampleAsType() {
+ if _, err := os.Open("non-existing"); err != nil {
+ if pathError, ok := errors.AsType[*fs.PathError](err); ok {
+ fmt.Println("Failed at path:", pathError.Path)
+ } else {
+ fmt.Println(err)
+ }
+ }
+ // Output:
+ // Failed at path: non-existing
+}
+
+type MyAsError struct {
+ err string
+}
+
+func (e MyAsError) Error() string {
+ return e.err
+}
+func (e MyAsError) As(target any) bool {
+ pe, ok := target.(**fs.PathError)
+ if !ok {
+ return false
+ }
+ *pe = &fs.PathError{
+ Op: "custom",
+ Path: "/",
+ Err: errors.New(e.err),
+ }
+ return true
+}
+
+// Custom errors can implement a method "As(any) bool" to match against other error types,
+// overriding the default matching of [errors.As].
+func ExampleAs_custom_match() {
+ var err error = MyAsError{"an error"}
+ fmt.Println("Error:", err)
+ fmt.Printf("TypeOf err: %T\n", err)
+
+ var pathError *fs.PathError
+ ok := errors.As(err, &pathError)
+ fmt.Println("Error as fs.PathError:", ok)
+ fmt.Println("fs.PathError:", pathError)
+
+ // Output:
+ // Error: an error
+ // TypeOf err: errors_test.MyAsError
+ // Error as fs.PathError: true
+ // fs.PathError: custom /: an error
+}
+
+// Custom errors can implement a method "As(any) bool" to match against other error types,
+// overriding the default matching of [errors.AsType].
+func ExampleAsType_custom_match() {
+ var err error = MyAsError{"an error"}
+ fmt.Println("Error:", err)
+ fmt.Printf("TypeOf err: %T\n", err)
+
+ pathError, ok := errors.AsType[*fs.PathError](err)
+ fmt.Println("Error as fs.PathError:", ok)
+ fmt.Println("fs.PathError:", pathError)
+
+ // Output:
+ // Error: an error
+ // TypeOf err: errors_test.MyAsError
+ // Error as fs.PathError: true
+ // fs.PathError: custom /: an error
+}
+
+func ExampleUnwrap() {
+ err1 := errors.New("error1")
+ err2 := fmt.Errorf("error2: [%w]", err1)
+ fmt.Println(err2)
+ fmt.Println(errors.Unwrap(err2))
+ // Output:
+ // error2: [error1]
+ // error1
+}
diff --git a/go/src/errors/join.go b/go/src/errors/join.go
new file mode 100644
index 0000000000000000000000000000000000000000..730bf7043c683f93dee2270aec25b13380c987b6
--- /dev/null
+++ b/go/src/errors/join.go
@@ -0,0 +1,63 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package errors
+
+import (
+ "unsafe"
+)
+
+// Join returns an error that wraps the given errors.
+// Any nil error values are discarded.
+// Join returns nil if every value in errs is nil.
+// The error formats as the concatenation of the strings obtained
+// by calling the Error method of each element of errs, with a newline
+// between each string.
+//
+// A non-nil error returned by Join implements the Unwrap() []error method.
+// The errors may be inspected with [Is] and [As].
+func Join(errs ...error) error {
+ n := 0
+ for _, err := range errs {
+ if err != nil {
+ n++
+ }
+ }
+ if n == 0 {
+ return nil
+ }
+ e := &joinError{
+ errs: make([]error, 0, n),
+ }
+ for _, err := range errs {
+ if err != nil {
+ e.errs = append(e.errs, err)
+ }
+ }
+ return e
+}
+
+type joinError struct {
+ errs []error
+}
+
+func (e *joinError) Error() string {
+ // Since Join returns nil if every value in errs is nil,
+ // e.errs cannot be empty.
+ if len(e.errs) == 1 {
+ return e.errs[0].Error()
+ }
+
+ b := []byte(e.errs[0].Error())
+ for _, err := range e.errs[1:] {
+ b = append(b, '\n')
+ b = append(b, err.Error()...)
+ }
+ // At this point, b has at least one byte '\n'.
+ return unsafe.String(&b[0], len(b))
+}
+
+func (e *joinError) Unwrap() []error {
+ return e.errs
+}
diff --git a/go/src/errors/join_test.go b/go/src/errors/join_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..8ee4d7f77be8856c1cd4d60fdafd2b5d0eb5cbff
--- /dev/null
+++ b/go/src/errors/join_test.go
@@ -0,0 +1,76 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package errors_test
+
+import (
+ "errors"
+ "reflect"
+ "testing"
+)
+
+func TestJoinReturnsNil(t *testing.T) {
+ if err := errors.Join(); err != nil {
+ t.Errorf("errors.Join() = %v, want nil", err)
+ }
+ if err := errors.Join(nil); err != nil {
+ t.Errorf("errors.Join(nil) = %v, want nil", err)
+ }
+ if err := errors.Join(nil, nil); err != nil {
+ t.Errorf("errors.Join(nil, nil) = %v, want nil", err)
+ }
+}
+
+func TestJoin(t *testing.T) {
+ err1 := errors.New("err1")
+ err2 := errors.New("err2")
+ merr := multiErr{errors.New("err3")}
+ for _, test := range []struct {
+ errs []error
+ want []error
+ }{{
+ errs: []error{err1},
+ want: []error{err1},
+ }, {
+ errs: []error{err1, err2},
+ want: []error{err1, err2},
+ }, {
+ errs: []error{err1, nil, err2},
+ want: []error{err1, err2},
+ }, {
+ errs: []error{merr},
+ want: []error{merr},
+ }} {
+ got := errors.Join(test.errs...).(interface{ Unwrap() []error }).Unwrap()
+ if !reflect.DeepEqual(got, test.want) {
+ t.Errorf("Join(%v) = %v; want %v", test.errs, got, test.want)
+ }
+ if len(got) != cap(got) {
+ t.Errorf("Join(%v) returns errors with len=%v, cap=%v; want len==cap", test.errs, len(got), cap(got))
+ }
+ }
+}
+
+func TestJoinErrorMethod(t *testing.T) {
+ err1 := errors.New("err1")
+ err2 := errors.New("err2")
+ for _, test := range []struct {
+ errs []error
+ want string
+ }{{
+ errs: []error{err1},
+ want: "err1",
+ }, {
+ errs: []error{err1, err2},
+ want: "err1\nerr2",
+ }, {
+ errs: []error{err1, nil, err2},
+ want: "err1\nerr2",
+ }} {
+ got := errors.Join(test.errs...).Error()
+ if got != test.want {
+ t.Errorf("Join(%v).Error() = %q; want %q", test.errs, got, test.want)
+ }
+ }
+}
diff --git a/go/src/errors/wrap.go b/go/src/errors/wrap.go
new file mode 100644
index 0000000000000000000000000000000000000000..e4a5ca33d5e0e7ef3b05c24eb5a516a749decea1
--- /dev/null
+++ b/go/src/errors/wrap.go
@@ -0,0 +1,209 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package errors
+
+import (
+ "internal/reflectlite"
+)
+
+// Unwrap returns the result of calling the Unwrap method on err, if err's
+// type contains an Unwrap method returning error.
+// Otherwise, Unwrap returns nil.
+//
+// Unwrap only calls a method of the form "Unwrap() error".
+// In particular Unwrap does not unwrap errors returned by [Join].
+func Unwrap(err error) error {
+ u, ok := err.(interface {
+ Unwrap() error
+ })
+ if !ok {
+ return nil
+ }
+ return u.Unwrap()
+}
+
+// Is reports whether any error in err's tree matches target.
+// The target must be comparable.
+//
+// The tree consists of err itself, followed by the errors obtained by repeatedly
+// calling its Unwrap() error or Unwrap() []error method. When err wraps multiple
+// errors, Is examines err followed by a depth-first traversal of its children.
+//
+// An error is considered to match a target if it is equal to that target or if
+// it implements a method Is(error) bool such that Is(target) returns true.
+//
+// An error type might provide an Is method so it can be treated as equivalent
+// to an existing error. For example, if MyError defines
+//
+// func (m MyError) Is(target error) bool { return target == fs.ErrExist }
+//
+// then Is(MyError{}, fs.ErrExist) returns true. See [syscall.Errno.Is] for
+// an example in the standard library. An Is method should only shallowly
+// compare err and the target and not call [Unwrap] on either.
+func Is(err, target error) bool {
+ if err == nil || target == nil {
+ return err == target
+ }
+
+ isComparable := reflectlite.TypeOf(target).Comparable()
+ return is(err, target, isComparable)
+}
+
+func is(err, target error, targetComparable bool) bool {
+ for {
+ if targetComparable && err == target {
+ return true
+ }
+ if x, ok := err.(interface{ Is(error) bool }); ok && x.Is(target) {
+ return true
+ }
+ switch x := err.(type) {
+ case interface{ Unwrap() error }:
+ err = x.Unwrap()
+ if err == nil {
+ return false
+ }
+ case interface{ Unwrap() []error }:
+ for _, err := range x.Unwrap() {
+ if is(err, target, targetComparable) {
+ return true
+ }
+ }
+ return false
+ default:
+ return false
+ }
+ }
+}
+
+// As finds the first error in err's tree that matches target, and if one is found, sets
+// target to that error value and returns true. Otherwise, it returns false.
+//
+// For most uses, prefer [AsType]. As is equivalent to [AsType] but sets its target
+// argument rather than returning the matching error and doesn't require its target
+// argument to implement error.
+//
+// The tree consists of err itself, followed by the errors obtained by repeatedly
+// calling its Unwrap() error or Unwrap() []error method. When err wraps multiple
+// errors, As examines err followed by a depth-first traversal of its children.
+//
+// An error matches target if the error's concrete value is assignable to the value
+// pointed to by target, or if the error has a method As(any) bool such that
+// As(target) returns true. In the latter case, the As method is responsible for
+// setting target.
+//
+// An error type might provide an As method so it can be treated as if it were a
+// different error type.
+//
+// As panics if target is not a non-nil pointer to either a type that implements
+// error, or to any interface type.
+func As(err error, target any) bool {
+ if err == nil {
+ return false
+ }
+ if target == nil {
+ panic("errors: target cannot be nil")
+ }
+ val := reflectlite.ValueOf(target)
+ typ := val.Type()
+ if typ.Kind() != reflectlite.Ptr || val.IsNil() {
+ panic("errors: target must be a non-nil pointer")
+ }
+ targetType := typ.Elem()
+ if targetType.Kind() != reflectlite.Interface && !targetType.Implements(errorType) {
+ panic("errors: *target must be interface or implement error")
+ }
+ return as(err, target, val, targetType)
+}
+
+func as(err error, target any, targetVal reflectlite.Value, targetType reflectlite.Type) bool {
+ for {
+ if reflectlite.TypeOf(err).AssignableTo(targetType) {
+ targetVal.Elem().Set(reflectlite.ValueOf(err))
+ return true
+ }
+ if x, ok := err.(interface{ As(any) bool }); ok && x.As(target) {
+ return true
+ }
+ switch x := err.(type) {
+ case interface{ Unwrap() error }:
+ err = x.Unwrap()
+ if err == nil {
+ return false
+ }
+ case interface{ Unwrap() []error }:
+ for _, err := range x.Unwrap() {
+ if err == nil {
+ continue
+ }
+ if as(err, target, targetVal, targetType) {
+ return true
+ }
+ }
+ return false
+ default:
+ return false
+ }
+ }
+}
+
+var errorType = reflectlite.TypeOf((*error)(nil)).Elem()
+
+// AsType finds the first error in err's tree that matches the type E, and
+// if one is found, returns that error value and true. Otherwise, it
+// returns the zero value of E and false.
+//
+// The tree consists of err itself, followed by the errors obtained by
+// repeatedly calling its Unwrap() error or Unwrap() []error method. When
+// err wraps multiple errors, AsType examines err followed by a
+// depth-first traversal of its children.
+//
+// An error err matches the type E if the type assertion err.(E) holds,
+// or if the error has a method As(any) bool such that err.As(target)
+// returns true when target is a non-nil *E. In the latter case, the As
+// method is responsible for setting target.
+func AsType[E error](err error) (E, bool) {
+ if err == nil {
+ var zero E
+ return zero, false
+ }
+ var pe *E // lazily initialized
+ return asType(err, &pe)
+}
+
+func asType[E error](err error, ppe **E) (_ E, _ bool) {
+ for {
+ if e, ok := err.(E); ok {
+ return e, true
+ }
+ if x, ok := err.(interface{ As(any) bool }); ok {
+ if *ppe == nil {
+ *ppe = new(E)
+ }
+ if x.As(*ppe) {
+ return **ppe, true
+ }
+ }
+ switch x := err.(type) {
+ case interface{ Unwrap() error }:
+ err = x.Unwrap()
+ if err == nil {
+ return
+ }
+ case interface{ Unwrap() []error }:
+ for _, err := range x.Unwrap() {
+ if err == nil {
+ continue
+ }
+ if x, ok := asType(err, ppe); ok {
+ return x, true
+ }
+ }
+ return
+ default:
+ return
+ }
+ }
+}
diff --git a/go/src/errors/wrap_test.go b/go/src/errors/wrap_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..81c795a6bb8b18355ae73f4398c9ac8c755c91df
--- /dev/null
+++ b/go/src/errors/wrap_test.go
@@ -0,0 +1,438 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package errors_test
+
+import (
+ "errors"
+ "fmt"
+ "io/fs"
+ "os"
+ "reflect"
+ "testing"
+)
+
+func TestIs(t *testing.T) {
+ err1 := errors.New("1")
+ erra := wrapped{"wrap 2", err1}
+ errb := wrapped{"wrap 3", erra}
+
+ err3 := errors.New("3")
+
+ poser := &poser{"either 1 or 3", func(err error) bool {
+ return err == err1 || err == err3
+ }}
+
+ testCases := []struct {
+ err error
+ target error
+ match bool
+ }{
+ {nil, nil, true},
+ {nil, err1, false},
+ {err1, nil, false},
+ {err1, err1, true},
+ {erra, err1, true},
+ {errb, err1, true},
+ {err1, err3, false},
+ {erra, err3, false},
+ {errb, err3, false},
+ {poser, err1, true},
+ {poser, err3, true},
+ {poser, erra, false},
+ {poser, errb, false},
+ {errorUncomparable{}, errorUncomparable{}, true},
+ {errorUncomparable{}, &errorUncomparable{}, false},
+ {&errorUncomparable{}, errorUncomparable{}, true},
+ {&errorUncomparable{}, &errorUncomparable{}, false},
+ {errorUncomparable{}, err1, false},
+ {&errorUncomparable{}, err1, false},
+ {multiErr{}, err1, false},
+ {multiErr{err1, err3}, err1, true},
+ {multiErr{err3, err1}, err1, true},
+ {multiErr{err1, err3}, errors.New("x"), false},
+ {multiErr{err3, errb}, errb, true},
+ {multiErr{err3, errb}, erra, true},
+ {multiErr{err3, errb}, err1, true},
+ {multiErr{errb, err3}, err1, true},
+ {multiErr{poser}, err1, true},
+ {multiErr{poser}, err3, true},
+ {multiErr{nil}, nil, false},
+ }
+ for _, tc := range testCases {
+ t.Run("", func(t *testing.T) {
+ if got := errors.Is(tc.err, tc.target); got != tc.match {
+ t.Errorf("Is(%v, %v) = %v, want %v", tc.err, tc.target, got, tc.match)
+ }
+ })
+ }
+}
+
+type poser struct {
+ msg string
+ f func(error) bool
+}
+
+var poserPathErr = &fs.PathError{Op: "poser"}
+
+func (p *poser) Error() string { return p.msg }
+func (p *poser) Is(err error) bool { return p.f(err) }
+func (p *poser) As(err any) bool {
+ switch x := err.(type) {
+ case **poser:
+ *x = p
+ case *errorT:
+ *x = errorT{"poser"}
+ case **fs.PathError:
+ *x = poserPathErr
+ default:
+ return false
+ }
+ return true
+}
+
+func TestAs(t *testing.T) {
+ var errT errorT
+ var errP *fs.PathError
+ var timeout interface{ Timeout() bool }
+ var p *poser
+ _, errF := os.Open("non-existing")
+ poserErr := &poser{"oh no", nil}
+
+ testCases := []struct {
+ err error
+ target any
+ match bool
+ want any // value of target on match
+ }{{
+ nil,
+ &errP,
+ false,
+ nil,
+ }, {
+ wrapped{"pitied the fool", errorT{"T"}},
+ &errT,
+ true,
+ errorT{"T"},
+ }, {
+ errF,
+ &errP,
+ true,
+ errF,
+ }, {
+ errorT{},
+ &errP,
+ false,
+ nil,
+ }, {
+ wrapped{"wrapped", nil},
+ &errT,
+ false,
+ nil,
+ }, {
+ &poser{"error", nil},
+ &errT,
+ true,
+ errorT{"poser"},
+ }, {
+ &poser{"path", nil},
+ &errP,
+ true,
+ poserPathErr,
+ }, {
+ poserErr,
+ &p,
+ true,
+ poserErr,
+ }, {
+ errors.New("err"),
+ &timeout,
+ false,
+ nil,
+ }, {
+ errF,
+ &timeout,
+ true,
+ errF,
+ }, {
+ wrapped{"path error", errF},
+ &timeout,
+ true,
+ errF,
+ }, {
+ multiErr{},
+ &errT,
+ false,
+ nil,
+ }, {
+ multiErr{errors.New("a"), errorT{"T"}},
+ &errT,
+ true,
+ errorT{"T"},
+ }, {
+ multiErr{errorT{"T"}, errors.New("a")},
+ &errT,
+ true,
+ errorT{"T"},
+ }, {
+ multiErr{errorT{"a"}, errorT{"b"}},
+ &errT,
+ true,
+ errorT{"a"},
+ }, {
+ multiErr{multiErr{errors.New("a"), errorT{"a"}}, errorT{"b"}},
+ &errT,
+ true,
+ errorT{"a"},
+ }, {
+ multiErr{wrapped{"path error", errF}},
+ &timeout,
+ true,
+ errF,
+ }, {
+ multiErr{nil},
+ &errT,
+ false,
+ nil,
+ }}
+ for i, tc := range testCases {
+ name := fmt.Sprintf("%d:As(Errorf(..., %v), %v)", i, tc.err, tc.target)
+ // Clear the target pointer, in case it was set in a previous test.
+ rtarget := reflect.ValueOf(tc.target)
+ rtarget.Elem().Set(reflect.Zero(reflect.TypeOf(tc.target).Elem()))
+ t.Run(name, func(t *testing.T) {
+ match := errors.As(tc.err, tc.target)
+ if match != tc.match {
+ t.Fatalf("match: got %v; want %v", match, tc.match)
+ }
+ if !match {
+ return
+ }
+ if got := rtarget.Elem().Interface(); got != tc.want {
+ t.Fatalf("got %#v, want %#v", got, tc.want)
+ }
+ })
+ }
+}
+
+func TestAsValidation(t *testing.T) {
+ var s string
+ testCases := []any{
+ nil,
+ (*int)(nil),
+ "error",
+ &s,
+ }
+ err := errors.New("error")
+ for _, tc := range testCases {
+ t.Run(fmt.Sprintf("%T(%v)", tc, tc), func(t *testing.T) {
+ defer func() {
+ recover()
+ }()
+ if errors.As(err, tc) {
+ t.Errorf("As(err, %T(%v)) = true, want false", tc, tc)
+ return
+ }
+ t.Errorf("As(err, %T(%v)) did not panic", tc, tc)
+ })
+ }
+}
+
+func TestAsType(t *testing.T) {
+ var errT errorT
+ var errP *fs.PathError
+ type timeout interface {
+ Timeout() bool
+ error
+ }
+ _, errF := os.Open("non-existing")
+ poserErr := &poser{"oh no", nil}
+
+ testAsType(t,
+ nil,
+ errP,
+ false,
+ )
+ testAsType(t,
+ wrapped{"pitied the fool", errorT{"T"}},
+ errorT{"T"},
+ true,
+ )
+ testAsType(t,
+ errF,
+ errF,
+ true,
+ )
+ testAsType(t,
+ errT,
+ errP,
+ false,
+ )
+ testAsType(t,
+ wrapped{"wrapped", nil},
+ errT,
+ false,
+ )
+ testAsType(t,
+ &poser{"error", nil},
+ errorT{"poser"},
+ true,
+ )
+ testAsType(t,
+ &poser{"path", nil},
+ poserPathErr,
+ true,
+ )
+ testAsType(t,
+ poserErr,
+ poserErr,
+ true,
+ )
+ testAsType(t,
+ errors.New("err"),
+ timeout(nil),
+ false,
+ )
+ testAsType(t,
+ errF,
+ errF.(timeout),
+ true)
+ testAsType(t,
+ wrapped{"path error", errF},
+ errF.(timeout),
+ true,
+ )
+ testAsType(t,
+ multiErr{},
+ errT,
+ false,
+ )
+ testAsType(t,
+ multiErr{errors.New("a"), errorT{"T"}},
+ errorT{"T"},
+ true,
+ )
+ testAsType(t,
+ multiErr{errorT{"T"}, errors.New("a")},
+ errorT{"T"},
+ true,
+ )
+ testAsType(t,
+ multiErr{errorT{"a"}, errorT{"b"}},
+ errorT{"a"},
+ true,
+ )
+ testAsType(t,
+ multiErr{multiErr{errors.New("a"), errorT{"a"}}, errorT{"b"}},
+ errorT{"a"},
+ true,
+ )
+ testAsType(t,
+ multiErr{wrapped{"path error", errF}},
+ errF.(timeout),
+ true,
+ )
+ testAsType(t,
+ multiErr{nil},
+ errT,
+ false,
+ )
+}
+
+type compError interface {
+ comparable
+ error
+}
+
+func testAsType[E compError](t *testing.T, err error, want E, wantOK bool) {
+ t.Helper()
+ name := fmt.Sprintf("AsType[%T](Errorf(..., %v))", want, err)
+ t.Run(name, func(t *testing.T) {
+ got, gotOK := errors.AsType[E](err)
+ if gotOK != wantOK || got != want {
+ t.Fatalf("got %v, %t; want %v, %t", got, gotOK, want, wantOK)
+ }
+ })
+}
+
+func BenchmarkIs(b *testing.B) {
+ err1 := errors.New("1")
+ err2 := multiErr{multiErr{multiErr{err1, errorT{"a"}}, errorT{"b"}}}
+
+ for i := 0; i < b.N; i++ {
+ if !errors.Is(err2, err1) {
+ b.Fatal("Is failed")
+ }
+ }
+}
+
+func BenchmarkAs(b *testing.B) {
+ err := multiErr{multiErr{multiErr{errors.New("a"), errorT{"a"}}, errorT{"b"}}}
+ for i := 0; i < b.N; i++ {
+ var target errorT
+ if !errors.As(err, &target) {
+ b.Fatal("As failed")
+ }
+ }
+}
+
+func BenchmarkAsType(b *testing.B) {
+ err := multiErr{multiErr{multiErr{errors.New("a"), errorT{"a"}}, errorT{"b"}}}
+ for range b.N {
+ if _, ok := errors.AsType[errorT](err); !ok {
+ b.Fatal("AsType failed")
+ }
+ }
+}
+
+func TestUnwrap(t *testing.T) {
+ err1 := errors.New("1")
+ erra := wrapped{"wrap 2", err1}
+
+ testCases := []struct {
+ err error
+ want error
+ }{
+ {nil, nil},
+ {wrapped{"wrapped", nil}, nil},
+ {err1, nil},
+ {erra, err1},
+ {wrapped{"wrap 3", erra}, erra},
+ }
+ for _, tc := range testCases {
+ if got := errors.Unwrap(tc.err); got != tc.want {
+ t.Errorf("Unwrap(%v) = %v, want %v", tc.err, got, tc.want)
+ }
+ }
+}
+
+type errorT struct{ s string }
+
+func (e errorT) Error() string { return fmt.Sprintf("errorT(%s)", e.s) }
+
+type wrapped struct {
+ msg string
+ err error
+}
+
+func (e wrapped) Error() string { return e.msg }
+func (e wrapped) Unwrap() error { return e.err }
+
+type multiErr []error
+
+func (m multiErr) Error() string { return "multiError" }
+func (m multiErr) Unwrap() []error { return []error(m) }
+
+type errorUncomparable struct {
+ f []string
+}
+
+func (errorUncomparable) Error() string {
+ return "uncomparable error"
+}
+
+func (errorUncomparable) Is(target error) bool {
+ _, ok := target.(errorUncomparable)
+ return ok
+}
diff --git a/go/src/expvar/expvar.go b/go/src/expvar/expvar.go
new file mode 100644
index 0000000000000000000000000000000000000000..4f66848f1fe4cf94ea9b50f02beef556ec57270d
--- /dev/null
+++ b/go/src/expvar/expvar.go
@@ -0,0 +1,417 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package expvar provides a standardized interface to public variables, such
+// as operation counters in servers. It exposes these variables via HTTP at
+// /debug/vars in JSON format. As of Go 1.22, the /debug/vars request must
+// use GET.
+//
+// Operations to set or modify these public variables are atomic.
+//
+// In addition to adding the HTTP handler, this package registers the
+// following variables:
+//
+// cmdline os.Args
+// memstats runtime.Memstats
+//
+// The package is sometimes only imported for the side effect of
+// registering its HTTP handler and the above variables. To use it
+// this way, link this package into your program:
+//
+// import _ "expvar"
+package expvar
+
+import (
+ "encoding/json"
+ "internal/godebug"
+ "log"
+ "math"
+ "net/http"
+ "os"
+ "runtime"
+ "slices"
+ "strconv"
+ "sync"
+ "sync/atomic"
+ "unicode/utf8"
+)
+
+// Var is an abstract type for all exported variables.
+type Var interface {
+ // String returns a valid JSON value for the variable.
+ // Types with String methods that do not return valid JSON
+ // (such as time.Time) must not be used as a Var.
+ String() string
+}
+
+type jsonVar interface {
+ // appendJSON appends the JSON representation of the receiver to b.
+ appendJSON(b []byte) []byte
+}
+
+// Int is a 64-bit integer variable that satisfies the [Var] interface.
+type Int struct {
+ i atomic.Int64
+}
+
+func (v *Int) Value() int64 {
+ return v.i.Load()
+}
+
+func (v *Int) String() string {
+ return string(v.appendJSON(nil))
+}
+
+func (v *Int) appendJSON(b []byte) []byte {
+ return strconv.AppendInt(b, v.i.Load(), 10)
+}
+
+func (v *Int) Add(delta int64) {
+ v.i.Add(delta)
+}
+
+func (v *Int) Set(value int64) {
+ v.i.Store(value)
+}
+
+// Float is a 64-bit float variable that satisfies the [Var] interface.
+type Float struct {
+ f atomic.Uint64
+}
+
+func (v *Float) Value() float64 {
+ return math.Float64frombits(v.f.Load())
+}
+
+func (v *Float) String() string {
+ return string(v.appendJSON(nil))
+}
+
+func (v *Float) appendJSON(b []byte) []byte {
+ return strconv.AppendFloat(b, math.Float64frombits(v.f.Load()), 'g', -1, 64)
+}
+
+// Add adds delta to v.
+func (v *Float) Add(delta float64) {
+ for {
+ cur := v.f.Load()
+ curVal := math.Float64frombits(cur)
+ nxtVal := curVal + delta
+ nxt := math.Float64bits(nxtVal)
+ if v.f.CompareAndSwap(cur, nxt) {
+ return
+ }
+ }
+}
+
+// Set sets v to value.
+func (v *Float) Set(value float64) {
+ v.f.Store(math.Float64bits(value))
+}
+
+// Map is a string-to-Var map variable that satisfies the [Var] interface.
+type Map struct {
+ m sync.Map // map[string]Var
+ keysMu sync.RWMutex
+ keys []string // sorted
+}
+
+// KeyValue represents a single entry in a [Map].
+type KeyValue struct {
+ Key string
+ Value Var
+}
+
+func (v *Map) String() string {
+ return string(v.appendJSON(nil))
+}
+
+func (v *Map) appendJSON(b []byte) []byte {
+ return v.appendJSONMayExpand(b, false)
+}
+
+func (v *Map) appendJSONMayExpand(b []byte, expand bool) []byte {
+ afterCommaDelim := byte(' ')
+ mayAppendNewline := func(b []byte) []byte { return b }
+ if expand {
+ afterCommaDelim = '\n'
+ mayAppendNewline = func(b []byte) []byte { return append(b, '\n') }
+ }
+
+ b = append(b, '{')
+ b = mayAppendNewline(b)
+ first := true
+ v.Do(func(kv KeyValue) {
+ if !first {
+ b = append(b, ',', afterCommaDelim)
+ }
+ first = false
+ b = appendJSONQuote(b, kv.Key)
+ b = append(b, ':', ' ')
+ switch v := kv.Value.(type) {
+ case nil:
+ b = append(b, "null"...)
+ case jsonVar:
+ b = v.appendJSON(b)
+ default:
+ b = append(b, v.String()...)
+ }
+ })
+ b = mayAppendNewline(b)
+ b = append(b, '}')
+ b = mayAppendNewline(b)
+ return b
+}
+
+// Init removes all keys from the map.
+func (v *Map) Init() *Map {
+ v.keysMu.Lock()
+ defer v.keysMu.Unlock()
+ v.keys = v.keys[:0]
+ v.m.Clear()
+ return v
+}
+
+// addKey updates the sorted list of keys in v.keys.
+func (v *Map) addKey(key string) {
+ v.keysMu.Lock()
+ defer v.keysMu.Unlock()
+ // Using insertion sort to place key into the already-sorted v.keys.
+ i, found := slices.BinarySearch(v.keys, key)
+ if found {
+ return
+ }
+ v.keys = slices.Insert(v.keys, i, key)
+}
+
+func (v *Map) Get(key string) Var {
+ i, _ := v.m.Load(key)
+ av, _ := i.(Var)
+ return av
+}
+
+func (v *Map) Set(key string, av Var) {
+ // Before we store the value, check to see whether the key is new. Try a Load
+ // before LoadOrStore: LoadOrStore causes the key interface to escape even on
+ // the Load path.
+ if _, ok := v.m.Load(key); !ok {
+ if _, dup := v.m.LoadOrStore(key, av); !dup {
+ v.addKey(key)
+ return
+ }
+ }
+
+ v.m.Store(key, av)
+}
+
+// Add adds delta to the *[Int] value stored under the given map key.
+func (v *Map) Add(key string, delta int64) {
+ i, ok := v.m.Load(key)
+ if !ok {
+ var dup bool
+ i, dup = v.m.LoadOrStore(key, new(Int))
+ if !dup {
+ v.addKey(key)
+ }
+ }
+
+ // Add to Int; ignore otherwise.
+ if iv, ok := i.(*Int); ok {
+ iv.Add(delta)
+ }
+}
+
+// AddFloat adds delta to the *[Float] value stored under the given map key.
+func (v *Map) AddFloat(key string, delta float64) {
+ i, ok := v.m.Load(key)
+ if !ok {
+ var dup bool
+ i, dup = v.m.LoadOrStore(key, new(Float))
+ if !dup {
+ v.addKey(key)
+ }
+ }
+
+ // Add to Float; ignore otherwise.
+ if iv, ok := i.(*Float); ok {
+ iv.Add(delta)
+ }
+}
+
+// Delete deletes the given key from the map.
+func (v *Map) Delete(key string) {
+ v.keysMu.Lock()
+ defer v.keysMu.Unlock()
+ i, found := slices.BinarySearch(v.keys, key)
+ if found {
+ v.keys = slices.Delete(v.keys, i, i+1)
+ v.m.Delete(key)
+ }
+}
+
+// Do calls f for each entry in the map.
+// The map is locked during the iteration,
+// but existing entries may be concurrently updated.
+func (v *Map) Do(f func(KeyValue)) {
+ v.keysMu.RLock()
+ defer v.keysMu.RUnlock()
+ for _, k := range v.keys {
+ i, _ := v.m.Load(k)
+ val, _ := i.(Var)
+ f(KeyValue{k, val})
+ }
+}
+
+// String is a string variable, and satisfies the [Var] interface.
+type String struct {
+ s atomic.Value // string
+}
+
+func (v *String) Value() string {
+ p, _ := v.s.Load().(string)
+ return p
+}
+
+// String implements the [Var] interface. To get the unquoted string
+// use [String.Value].
+func (v *String) String() string {
+ return string(v.appendJSON(nil))
+}
+
+func (v *String) appendJSON(b []byte) []byte {
+ return appendJSONQuote(b, v.Value())
+}
+
+func (v *String) Set(value string) {
+ v.s.Store(value)
+}
+
+// Func implements [Var] by calling the function
+// and formatting the returned value using JSON.
+type Func func() any
+
+func (f Func) Value() any {
+ return f()
+}
+
+func (f Func) String() string {
+ v, _ := json.Marshal(f())
+ return string(v)
+}
+
+// All published variables.
+var vars Map
+
+// Publish declares a named exported variable. This should be called from a
+// package's init function when it creates its Vars. If the name is already
+// registered then this will log.Panic.
+func Publish(name string, v Var) {
+ if _, dup := vars.m.LoadOrStore(name, v); dup {
+ log.Panicln("Reuse of exported var name:", name)
+ }
+ vars.keysMu.Lock()
+ defer vars.keysMu.Unlock()
+ vars.keys = append(vars.keys, name)
+ slices.Sort(vars.keys)
+}
+
+// Get retrieves a named exported variable. It returns nil if the name has
+// not been registered.
+func Get(name string) Var {
+ return vars.Get(name)
+}
+
+// Convenience functions for creating new exported variables.
+
+func NewInt(name string) *Int {
+ v := new(Int)
+ Publish(name, v)
+ return v
+}
+
+func NewFloat(name string) *Float {
+ v := new(Float)
+ Publish(name, v)
+ return v
+}
+
+func NewMap(name string) *Map {
+ v := new(Map).Init()
+ Publish(name, v)
+ return v
+}
+
+func NewString(name string) *String {
+ v := new(String)
+ Publish(name, v)
+ return v
+}
+
+// Do calls f for each exported variable.
+// The global variable map is locked during the iteration,
+// but existing entries may be concurrently updated.
+func Do(f func(KeyValue)) {
+ vars.Do(f)
+}
+
+func expvarHandler(w http.ResponseWriter, r *http.Request) {
+ w.Header().Set("Content-Type", "application/json; charset=utf-8")
+ w.Write(vars.appendJSONMayExpand(nil, true))
+}
+
+// Handler returns the expvar HTTP Handler.
+//
+// This is only needed to install the handler in a non-standard location.
+func Handler() http.Handler {
+ return http.HandlerFunc(expvarHandler)
+}
+
+func cmdline() any {
+ return os.Args
+}
+
+func memstats() any {
+ stats := new(runtime.MemStats)
+ runtime.ReadMemStats(stats)
+ return *stats
+}
+
+func init() {
+ if godebug.New("httpmuxgo121").Value() == "1" {
+ http.HandleFunc("/debug/vars", expvarHandler)
+ } else {
+ http.HandleFunc("GET /debug/vars", expvarHandler)
+ }
+ Publish("cmdline", Func(cmdline))
+ Publish("memstats", Func(memstats))
+}
+
+// TODO: Use json.appendString instead.
+func appendJSONQuote(b []byte, s string) []byte {
+ const hex = "0123456789abcdef"
+ b = append(b, '"')
+ for _, r := range s {
+ switch {
+ case r < ' ' || r == '\\' || r == '"' || r == '<' || r == '>' || r == '&' || r == '\u2028' || r == '\u2029':
+ switch r {
+ case '\\', '"':
+ b = append(b, '\\', byte(r))
+ case '\n':
+ b = append(b, '\\', 'n')
+ case '\r':
+ b = append(b, '\\', 'r')
+ case '\t':
+ b = append(b, '\\', 't')
+ default:
+ b = append(b, '\\', 'u', hex[(r>>12)&0xf], hex[(r>>8)&0xf], hex[(r>>4)&0xf], hex[(r>>0)&0xf])
+ }
+ case r < utf8.RuneSelf:
+ b = append(b, byte(r))
+ default:
+ b = utf8.AppendRune(b, r)
+ }
+ }
+ b = append(b, '"')
+ return b
+}
diff --git a/go/src/expvar/expvar_test.go b/go/src/expvar/expvar_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..def84179532e4e3530ac5ffcaa74e4fe164c0e70
--- /dev/null
+++ b/go/src/expvar/expvar_test.go
@@ -0,0 +1,669 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package expvar
+
+import (
+ "bytes"
+ "crypto/sha1"
+ "encoding/json"
+ "fmt"
+ "net"
+ "net/http/httptest"
+ "reflect"
+ "runtime"
+ "strconv"
+ "sync"
+ "sync/atomic"
+ "testing"
+)
+
+// RemoveAll removes all exported variables.
+// This is for tests only.
+func RemoveAll() {
+ vars.keysMu.Lock()
+ defer vars.keysMu.Unlock()
+ for _, k := range vars.keys {
+ vars.m.Delete(k)
+ }
+ vars.keys = nil
+}
+
+func TestNil(t *testing.T) {
+ RemoveAll()
+ val := Get("missing")
+ if val != nil {
+ t.Errorf("got %v, want nil", val)
+ }
+}
+
+func TestInt(t *testing.T) {
+ RemoveAll()
+ reqs := NewInt("requests")
+ if i := reqs.Value(); i != 0 {
+ t.Errorf("reqs.Value() = %v, want 0", i)
+ }
+ if reqs != Get("requests").(*Int) {
+ t.Errorf("Get() failed.")
+ }
+
+ reqs.Add(1)
+ reqs.Add(3)
+ if i := reqs.Value(); i != 4 {
+ t.Errorf("reqs.Value() = %v, want 4", i)
+ }
+
+ if s := reqs.String(); s != "4" {
+ t.Errorf("reqs.String() = %q, want \"4\"", s)
+ }
+
+ reqs.Set(-2)
+ if i := reqs.Value(); i != -2 {
+ t.Errorf("reqs.Value() = %v, want -2", i)
+ }
+}
+
+func BenchmarkIntAdd(b *testing.B) {
+ var v Int
+
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ v.Add(1)
+ }
+ })
+}
+
+func BenchmarkIntSet(b *testing.B) {
+ var v Int
+
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ v.Set(1)
+ }
+ })
+}
+
+func TestFloat(t *testing.T) {
+ RemoveAll()
+ reqs := NewFloat("requests-float")
+ if reqs.f.Load() != 0.0 {
+ t.Errorf("reqs.f = %v, want 0", reqs.f.Load())
+ }
+ if reqs != Get("requests-float").(*Float) {
+ t.Errorf("Get() failed.")
+ }
+
+ reqs.Add(1.5)
+ reqs.Add(1.25)
+ if v := reqs.Value(); v != 2.75 {
+ t.Errorf("reqs.Value() = %v, want 2.75", v)
+ }
+
+ if s := reqs.String(); s != "2.75" {
+ t.Errorf("reqs.String() = %q, want \"4.64\"", s)
+ }
+
+ reqs.Add(-2)
+ if v := reqs.Value(); v != 0.75 {
+ t.Errorf("reqs.Value() = %v, want 0.75", v)
+ }
+}
+
+func BenchmarkFloatAdd(b *testing.B) {
+ var f Float
+
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ f.Add(1.0)
+ }
+ })
+}
+
+func BenchmarkFloatSet(b *testing.B) {
+ var f Float
+
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ f.Set(1.0)
+ }
+ })
+}
+
+func TestString(t *testing.T) {
+ RemoveAll()
+ name := NewString("my-name")
+ if s := name.Value(); s != "" {
+ t.Errorf(`NewString("my-name").Value() = %q, want ""`, s)
+ }
+
+ name.Set("Mike")
+ if s, want := name.String(), `"Mike"`; s != want {
+ t.Errorf(`after name.Set("Mike"), name.String() = %q, want %q`, s, want)
+ }
+ if s, want := name.Value(), "Mike"; s != want {
+ t.Errorf(`after name.Set("Mike"), name.Value() = %q, want %q`, s, want)
+ }
+
+ // Make sure we produce safe JSON output.
+ name.Set("<")
+ if s, want := name.String(), "\"\\u003c\""; s != want {
+ t.Errorf(`after name.Set("<"), name.String() = %q, want %q`, s, want)
+ }
+}
+
+func BenchmarkStringSet(b *testing.B) {
+ var s String
+
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ s.Set("red")
+ }
+ })
+}
+
+func TestMapInit(t *testing.T) {
+ RemoveAll()
+ colors := NewMap("bike-shed-colors")
+ colors.Add("red", 1)
+ colors.Add("blue", 1)
+ colors.Add("chartreuse", 1)
+
+ n := 0
+ colors.Do(func(KeyValue) { n++ })
+ if n != 3 {
+ t.Errorf("after three Add calls with distinct keys, Do should invoke f 3 times; got %v", n)
+ }
+
+ colors.Init()
+
+ n = 0
+ colors.Do(func(KeyValue) { n++ })
+ if n != 0 {
+ t.Errorf("after Init, Do should invoke f 0 times; got %v", n)
+ }
+}
+
+func TestMapDelete(t *testing.T) {
+ RemoveAll()
+ colors := NewMap("bike-shed-colors")
+
+ colors.Add("red", 1)
+ colors.Add("red", 2)
+ colors.Add("blue", 4)
+
+ n := 0
+ colors.Do(func(KeyValue) { n++ })
+ if n != 2 {
+ t.Errorf("after two Add calls with distinct keys, Do should invoke f 2 times; got %v", n)
+ }
+
+ colors.Delete("red")
+ if v := colors.Get("red"); v != nil {
+ t.Errorf("removed red, Get should return nil; got %v", v)
+ }
+ n = 0
+ colors.Do(func(KeyValue) { n++ })
+ if n != 1 {
+ t.Errorf("removed red, Do should invoke f 1 times; got %v", n)
+ }
+
+ colors.Delete("notfound")
+ n = 0
+ colors.Do(func(KeyValue) { n++ })
+ if n != 1 {
+ t.Errorf("attempted to remove notfound, Do should invoke f 1 times; got %v", n)
+ }
+
+ colors.Delete("blue")
+ colors.Delete("blue")
+ if v := colors.Get("blue"); v != nil {
+ t.Errorf("removed blue, Get should return nil; got %v", v)
+ }
+ n = 0
+ colors.Do(func(KeyValue) { n++ })
+ if n != 0 {
+ t.Errorf("all keys removed, Do should invoke f 0 times; got %v", n)
+ }
+}
+
+func TestMapCounter(t *testing.T) {
+ RemoveAll()
+ colors := NewMap("bike-shed-colors")
+
+ colors.Add("red", 1)
+ colors.Add("red", 2)
+ colors.Add("blue", 4)
+ colors.AddFloat(`green "midori"`, 4.125)
+ if x := colors.Get("red").(*Int).Value(); x != 3 {
+ t.Errorf("colors.m[\"red\"] = %v, want 3", x)
+ }
+ if x := colors.Get("blue").(*Int).Value(); x != 4 {
+ t.Errorf("colors.m[\"blue\"] = %v, want 4", x)
+ }
+ if x := colors.Get(`green "midori"`).(*Float).Value(); x != 4.125 {
+ t.Errorf("colors.m[`green \"midori\"] = %v, want 4.125", x)
+ }
+
+ // colors.String() should be '{"red":3, "blue":4}',
+ // though the order of red and blue could vary.
+ s := colors.String()
+ var j any
+ err := json.Unmarshal([]byte(s), &j)
+ if err != nil {
+ t.Errorf("colors.String() isn't valid JSON: %v", err)
+ }
+ m, ok := j.(map[string]any)
+ if !ok {
+ t.Error("colors.String() didn't produce a map.")
+ }
+ red := m["red"]
+ x, ok := red.(float64)
+ if !ok {
+ t.Error("red.Kind() is not a number.")
+ }
+ if x != 3 {
+ t.Errorf("red = %v, want 3", x)
+ }
+}
+
+func TestMapNil(t *testing.T) {
+ RemoveAll()
+ const key = "key"
+ m := NewMap("issue527719")
+ m.Set(key, nil)
+ s := m.String()
+ var j any
+ if err := json.Unmarshal([]byte(s), &j); err != nil {
+ t.Fatalf("m.String() == %q isn't valid JSON: %v", s, err)
+ }
+ m2, ok := j.(map[string]any)
+ if !ok {
+ t.Fatalf("m.String() produced %T, wanted a map", j)
+ }
+ v, ok := m2[key]
+ if !ok {
+ t.Fatalf("missing %q in %v", key, m2)
+ }
+ if v != nil {
+ t.Fatalf("m[%q] = %v, want nil", key, v)
+ }
+}
+
+func BenchmarkMapSet(b *testing.B) {
+ m := new(Map).Init()
+
+ v := new(Int)
+
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ m.Set("red", v)
+ }
+ })
+}
+
+func BenchmarkMapSetDifferent(b *testing.B) {
+ procKeys := make([][]string, runtime.GOMAXPROCS(0))
+ for i := range procKeys {
+ keys := make([]string, 4)
+ for j := range keys {
+ keys[j] = fmt.Sprint(i, j)
+ }
+ procKeys[i] = keys
+ }
+
+ m := new(Map).Init()
+ v := new(Int)
+ b.ResetTimer()
+
+ var n int32
+ b.RunParallel(func(pb *testing.PB) {
+ i := int(atomic.AddInt32(&n, 1)-1) % len(procKeys)
+ keys := procKeys[i]
+
+ for pb.Next() {
+ for _, k := range keys {
+ m.Set(k, v)
+ }
+ }
+ })
+}
+
+// BenchmarkMapSetDifferentRandom simulates such a case where the concerned
+// keys of Map.Set are generated dynamically and as a result insertion is
+// out of order and the number of the keys may be large.
+func BenchmarkMapSetDifferentRandom(b *testing.B) {
+ keys := make([]string, 100)
+ for i := range keys {
+ keys[i] = fmt.Sprintf("%x", sha1.Sum([]byte(fmt.Sprint(i))))
+ }
+
+ v := new(Int)
+ b.ResetTimer()
+
+ for i := 0; i < b.N; i++ {
+ m := new(Map).Init()
+ for _, k := range keys {
+ m.Set(k, v)
+ }
+ }
+}
+
+func BenchmarkMapSetString(b *testing.B) {
+ m := new(Map).Init()
+
+ v := new(String)
+ v.Set("Hello, !")
+
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ m.Set("red", v)
+ }
+ })
+}
+
+func BenchmarkMapAddSame(b *testing.B) {
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ m := new(Map).Init()
+ m.Add("red", 1)
+ m.Add("red", 1)
+ m.Add("red", 1)
+ m.Add("red", 1)
+ }
+ })
+}
+
+func BenchmarkMapAddDifferent(b *testing.B) {
+ procKeys := make([][]string, runtime.GOMAXPROCS(0))
+ for i := range procKeys {
+ keys := make([]string, 4)
+ for j := range keys {
+ keys[j] = fmt.Sprint(i, j)
+ }
+ procKeys[i] = keys
+ }
+
+ b.ResetTimer()
+
+ var n int32
+ b.RunParallel(func(pb *testing.PB) {
+ i := int(atomic.AddInt32(&n, 1)-1) % len(procKeys)
+ keys := procKeys[i]
+
+ for pb.Next() {
+ m := new(Map).Init()
+ for _, k := range keys {
+ m.Add(k, 1)
+ }
+ }
+ })
+}
+
+// BenchmarkMapAddDifferentRandom simulates such a case where that the concerned
+// keys of Map.Add are generated dynamically and as a result insertion is out of
+// order and the number of the keys may be large.
+func BenchmarkMapAddDifferentRandom(b *testing.B) {
+ keys := make([]string, 100)
+ for i := range keys {
+ keys[i] = fmt.Sprintf("%x", sha1.Sum([]byte(fmt.Sprint(i))))
+ }
+
+ b.ResetTimer()
+
+ for i := 0; i < b.N; i++ {
+ m := new(Map).Init()
+ for _, k := range keys {
+ m.Add(k, 1)
+ }
+ }
+}
+
+func BenchmarkMapAddSameSteadyState(b *testing.B) {
+ m := new(Map).Init()
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ m.Add("red", 1)
+ }
+ })
+}
+
+func BenchmarkMapAddDifferentSteadyState(b *testing.B) {
+ procKeys := make([][]string, runtime.GOMAXPROCS(0))
+ for i := range procKeys {
+ keys := make([]string, 4)
+ for j := range keys {
+ keys[j] = fmt.Sprint(i, j)
+ }
+ procKeys[i] = keys
+ }
+
+ m := new(Map).Init()
+ b.ResetTimer()
+
+ var n int32
+ b.RunParallel(func(pb *testing.PB) {
+ i := int(atomic.AddInt32(&n, 1)-1) % len(procKeys)
+ keys := procKeys[i]
+
+ for pb.Next() {
+ for _, k := range keys {
+ m.Add(k, 1)
+ }
+ }
+ })
+}
+
+func TestFunc(t *testing.T) {
+ RemoveAll()
+ var x any = []string{"a", "b"}
+ f := Func(func() any { return x })
+ if s, exp := f.String(), `["a","b"]`; s != exp {
+ t.Errorf(`f.String() = %q, want %q`, s, exp)
+ }
+ if v := f.Value(); !reflect.DeepEqual(v, x) {
+ t.Errorf(`f.Value() = %q, want %q`, v, x)
+ }
+
+ x = 17
+ if s, exp := f.String(), `17`; s != exp {
+ t.Errorf(`f.String() = %q, want %q`, s, exp)
+ }
+}
+
+func TestHandler(t *testing.T) {
+ RemoveAll()
+ m := NewMap("map1")
+ m.Add("a", 1)
+ m.Add("z", 2)
+ m2 := NewMap("map2")
+ for i := 0; i < 9; i++ {
+ m2.Add(strconv.Itoa(i), int64(i))
+ }
+ rr := httptest.NewRecorder()
+ rr.Body = new(bytes.Buffer)
+ expvarHandler(rr, nil)
+ want := `{
+"map1": {"a": 1, "z": 2},
+"map2": {"0": 0, "1": 1, "2": 2, "3": 3, "4": 4, "5": 5, "6": 6, "7": 7, "8": 8}
+}
+`
+ if got := rr.Body.String(); got != want {
+ t.Errorf("HTTP handler wrote:\n%s\nWant:\n%s", got, want)
+ }
+}
+
+func BenchmarkMapString(b *testing.B) {
+ var m, m1, m2 Map
+ m.Set("map1", &m1)
+ m1.Add("a", 1)
+ m1.Add("z", 2)
+ m.Set("map2", &m2)
+ for i := 0; i < 9; i++ {
+ m2.Add(strconv.Itoa(i), int64(i))
+ }
+ var s1, s2 String
+ m.Set("str1", &s1)
+ s1.Set("hello, world!")
+ m.Set("str2", &s2)
+ s2.Set("fizz buzz")
+ b.ResetTimer()
+
+ b.ReportAllocs()
+ for i := 0; i < b.N; i++ {
+ _ = m.String()
+ }
+}
+
+func BenchmarkRealworldExpvarUsage(b *testing.B) {
+ var (
+ bytesSent Int
+ bytesRead Int
+ )
+
+ // The benchmark creates GOMAXPROCS client/server pairs.
+ // Each pair creates 4 goroutines: client reader/writer and server reader/writer.
+ // The benchmark stresses concurrent reading and writing to the same connection.
+ // Such pattern is used in net/http and net/rpc.
+
+ b.StopTimer()
+
+ P := runtime.GOMAXPROCS(0)
+ N := b.N / P
+ W := 1000
+
+ // Setup P client/server connections.
+ clients := make([]net.Conn, P)
+ servers := make([]net.Conn, P)
+ ln, err := net.Listen("tcp", "127.0.0.1:0")
+ if err != nil {
+ b.Fatalf("Listen failed: %v", err)
+ }
+ defer ln.Close()
+ done := make(chan bool, 1)
+ go func() {
+ for p := 0; p < P; p++ {
+ s, err := ln.Accept()
+ if err != nil {
+ b.Errorf("Accept failed: %v", err)
+ done <- false
+ return
+ }
+ servers[p] = s
+ }
+ done <- true
+ }()
+ for p := 0; p < P; p++ {
+ c, err := net.Dial("tcp", ln.Addr().String())
+ if err != nil {
+ <-done
+ b.Fatalf("Dial failed: %v", err)
+ }
+ clients[p] = c
+ }
+ if !<-done {
+ b.FailNow()
+ }
+
+ b.StartTimer()
+
+ var wg sync.WaitGroup
+ wg.Add(4 * P)
+ for p := 0; p < P; p++ {
+ // Client writer.
+ go func(c net.Conn) {
+ defer wg.Done()
+ var buf [1]byte
+ for i := 0; i < N; i++ {
+ v := byte(i)
+ for w := 0; w < W; w++ {
+ v *= v
+ }
+ buf[0] = v
+ n, err := c.Write(buf[:])
+ if err != nil {
+ b.Errorf("Write failed: %v", err)
+ return
+ }
+
+ bytesSent.Add(int64(n))
+ }
+ }(clients[p])
+
+ // Pipe between server reader and server writer.
+ pipe := make(chan byte, 128)
+
+ // Server reader.
+ go func(s net.Conn) {
+ defer wg.Done()
+ var buf [1]byte
+ for i := 0; i < N; i++ {
+ n, err := s.Read(buf[:])
+
+ if err != nil {
+ b.Errorf("Read failed: %v", err)
+ return
+ }
+
+ bytesRead.Add(int64(n))
+ pipe <- buf[0]
+ }
+ }(servers[p])
+
+ // Server writer.
+ go func(s net.Conn) {
+ defer wg.Done()
+ var buf [1]byte
+ for i := 0; i < N; i++ {
+ v := <-pipe
+ for w := 0; w < W; w++ {
+ v *= v
+ }
+ buf[0] = v
+ n, err := s.Write(buf[:])
+ if err != nil {
+ b.Errorf("Write failed: %v", err)
+ return
+ }
+
+ bytesSent.Add(int64(n))
+ }
+ s.Close()
+ }(servers[p])
+
+ // Client reader.
+ go func(c net.Conn) {
+ defer wg.Done()
+ var buf [1]byte
+ for i := 0; i < N; i++ {
+ n, err := c.Read(buf[:])
+
+ if err != nil {
+ b.Errorf("Read failed: %v", err)
+ return
+ }
+
+ bytesRead.Add(int64(n))
+ }
+ c.Close()
+ }(clients[p])
+ }
+ wg.Wait()
+}
+
+func TestAppendJSONQuote(t *testing.T) {
+ var b []byte
+ for i := 0; i < 128; i++ {
+ b = append(b, byte(i))
+ }
+ b = append(b, "\u2028\u2029"...)
+ got := string(appendJSONQuote(nil, string(b[:])))
+ want := `"` +
+ `\u0000\u0001\u0002\u0003\u0004\u0005\u0006\u0007\u0008\t\n\u000b\u000c\r\u000e\u000f` +
+ `\u0010\u0011\u0012\u0013\u0014\u0015\u0016\u0017\u0018\u0019\u001a\u001b\u001c\u001d\u001e\u001f` +
+ ` !\"#$%\u0026'()*+,-./0123456789:;\u003c=\u003e?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_` +
+ "`" + `abcdefghijklmnopqrstuvwxyz{|}~` + "\x7f" + `\u2028\u2029"`
+ if got != want {
+ t.Errorf("appendJSONQuote mismatch:\ngot %v\nwant %v", got, want)
+ }
+}
diff --git a/go/src/flag/example_flagset_test.go b/go/src/flag/example_flagset_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..cb177e2171e133d8ca8b3a655b2116a50e60676a
--- /dev/null
+++ b/go/src/flag/example_flagset_test.go
@@ -0,0 +1,57 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package flag_test
+
+import (
+ "flag"
+ "fmt"
+ "time"
+)
+
+func ExampleFlagSet() {
+
+ start := func(args []string) {
+ // A real program (not an example) would use flag.ExitOnError.
+ fs := flag.NewFlagSet("start", flag.ContinueOnError)
+ addr := fs.String("addr", ":8080", "`address` to listen on")
+ if err := fs.Parse(args); err != nil {
+ fmt.Printf("error: %s", err)
+ return
+ }
+ fmt.Printf("starting server on %s\n", *addr)
+ }
+
+ stop := func(args []string) {
+ fs := flag.NewFlagSet("stop", flag.ContinueOnError)
+ timeout := fs.Duration("timeout", time.Second, "stop timeout duration")
+ if err := fs.Parse(args); err != nil {
+ fmt.Printf("error: %s", err)
+ return
+ }
+ fmt.Printf("stopping server (timeout=%v)\n", *timeout)
+ }
+
+ main := func(args []string) {
+ subArgs := args[2:] // Drop program name and command.
+ switch args[1] {
+ case "start":
+ start(subArgs)
+ case "stop":
+ stop(subArgs)
+ default:
+ fmt.Printf("error: unknown command - %q\n", args[1])
+ // In a real program (not an example) print to os.Stderr and exit the program with non-zero value.
+ }
+ }
+
+ main([]string{"httpd", "start", "-addr", ":9999"})
+ main([]string{"httpd", "stop"})
+ main([]string{"http", "start", "-log-level", "verbose"})
+
+ // Output:
+ // starting server on :9999
+ // stopping server (timeout=1s)
+ // error: flag provided but not defined: -log-level
+}
diff --git a/go/src/flag/example_func_test.go b/go/src/flag/example_func_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..ac9f9858dfa0013228006cd1bdcb85137a07390c
--- /dev/null
+++ b/go/src/flag/example_func_test.go
@@ -0,0 +1,57 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package flag_test
+
+import (
+ "errors"
+ "flag"
+ "fmt"
+ "net"
+ "os"
+)
+
+func ExampleFunc() {
+ fs := flag.NewFlagSet("ExampleFunc", flag.ContinueOnError)
+ fs.SetOutput(os.Stdout)
+ var ip net.IP
+ fs.Func("ip", "`IP address` to parse", func(s string) error {
+ ip = net.ParseIP(s)
+ if ip == nil {
+ return errors.New("could not parse IP")
+ }
+ return nil
+ })
+ fs.Parse([]string{"-ip", "127.0.0.1"})
+ fmt.Printf("{ip: %v, loopback: %t}\n\n", ip, ip.IsLoopback())
+
+ // 256 is not a valid IPv4 component
+ fs.Parse([]string{"-ip", "256.0.0.1"})
+ fmt.Printf("{ip: %v, loopback: %t}\n\n", ip, ip.IsLoopback())
+
+ // Output:
+ // {ip: 127.0.0.1, loopback: true}
+ //
+ // invalid value "256.0.0.1" for flag -ip: could not parse IP
+ // Usage of ExampleFunc:
+ // -ip IP address
+ // IP address to parse
+ // {ip: , loopback: false}
+}
+
+func ExampleBoolFunc() {
+ fs := flag.NewFlagSet("ExampleBoolFunc", flag.ContinueOnError)
+ fs.SetOutput(os.Stdout)
+
+ fs.BoolFunc("log", "logs a dummy message", func(s string) error {
+ fmt.Println("dummy message:", s)
+ return nil
+ })
+ fs.Parse([]string{"-log"})
+ fs.Parse([]string{"-log=0"})
+
+ // Output:
+ // dummy message: true
+ // dummy message: 0
+}
diff --git a/go/src/flag/example_test.go b/go/src/flag/example_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..088447d43f6195cec3b72c45ac20801c4776ba43
--- /dev/null
+++ b/go/src/flag/example_test.go
@@ -0,0 +1,85 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// These examples demonstrate more intricate uses of the flag package.
+package flag_test
+
+import (
+ "errors"
+ "flag"
+ "fmt"
+ "strings"
+ "time"
+)
+
+// Example 1: A single string flag called "species" with default value "gopher".
+var species = flag.String("species", "gopher", "the species we are studying")
+
+// Example 2: Two flags sharing a variable, so we can have a shorthand.
+// The order of initialization is undefined, so make sure both use the
+// same default value. They must be set up with an init function.
+var gopherType string
+
+func init() {
+ const (
+ defaultGopher = "pocket"
+ usage = "the variety of gopher"
+ )
+ flag.StringVar(&gopherType, "gopher_type", defaultGopher, usage)
+ flag.StringVar(&gopherType, "g", defaultGopher, usage+" (shorthand)")
+}
+
+// Example 3: A user-defined flag type, a slice of durations.
+type interval []time.Duration
+
+// String is the method to format the flag's value, part of the flag.Value interface.
+// The String method's output will be used in diagnostics.
+func (i *interval) String() string {
+ return fmt.Sprint(*i)
+}
+
+// Set is the method to set the flag value, part of the flag.Value interface.
+// Set's argument is a string to be parsed to set the flag.
+// It's a comma-separated list, so we split it.
+func (i *interval) Set(value string) error {
+ // If we wanted to allow the flag to be set multiple times,
+ // accumulating values, we would delete this if statement.
+ // That would permit usages such as
+ // -deltaT 10s -deltaT 15s
+ // and other combinations.
+ if len(*i) > 0 {
+ return errors.New("interval flag already set")
+ }
+ for _, dt := range strings.Split(value, ",") {
+ duration, err := time.ParseDuration(dt)
+ if err != nil {
+ return err
+ }
+ *i = append(*i, duration)
+ }
+ return nil
+}
+
+// Define a flag to accumulate durations. Because it has a special type,
+// we need to use the Var function and therefore create the flag during
+// init.
+
+var intervalFlag interval
+
+func init() {
+ // Tie the command-line flag to the intervalFlag variable and
+ // set a usage message.
+ flag.Var(&intervalFlag, "deltaT", "comma-separated list of intervals to use between events")
+}
+
+func Example() {
+ // All the interesting pieces are with the variables declared above, but
+ // to enable the flag package to see the flags defined there, one must
+ // execute, typically at the start of main (not init!):
+ // flag.Parse()
+ // We don't call it here because this code is a function called "Example"
+ // that is part of the testing suite for the package, which has already
+ // parsed the flags. When viewed at pkg.go.dev, however, the function is
+ // renamed to "main" and it could be run as a standalone example.
+}
diff --git a/go/src/flag/example_textvar_test.go b/go/src/flag/example_textvar_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..8b8cbf6b6c8f6b8040096d75edcd97a830512214
--- /dev/null
+++ b/go/src/flag/example_textvar_test.go
@@ -0,0 +1,35 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package flag_test
+
+import (
+ "flag"
+ "fmt"
+ "net"
+ "os"
+)
+
+func ExampleTextVar() {
+ fs := flag.NewFlagSet("ExampleTextVar", flag.ContinueOnError)
+ fs.SetOutput(os.Stdout)
+ var ip net.IP
+ fs.TextVar(&ip, "ip", net.IPv4(192, 168, 0, 100), "`IP address` to parse")
+ fs.Parse([]string{"-ip", "127.0.0.1"})
+ fmt.Printf("{ip: %v}\n\n", ip)
+
+ // 256 is not a valid IPv4 component
+ ip = nil
+ fs.Parse([]string{"-ip", "256.0.0.1"})
+ fmt.Printf("{ip: %v}\n\n", ip)
+
+ // Output:
+ // {ip: 127.0.0.1}
+ //
+ // invalid value "256.0.0.1" for flag -ip: invalid IP address: 256.0.0.1
+ // Usage of ExampleTextVar:
+ // -ip IP address
+ // IP address to parse (default 192.168.0.100)
+ // {ip: }
+}
diff --git a/go/src/flag/example_value_test.go b/go/src/flag/example_value_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..9d464c62e876b94a07fde8d8cb61b180826ae7c1
--- /dev/null
+++ b/go/src/flag/example_value_test.go
@@ -0,0 +1,44 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package flag_test
+
+import (
+ "flag"
+ "fmt"
+ "net/url"
+)
+
+type URLValue struct {
+ URL *url.URL
+}
+
+func (v URLValue) String() string {
+ if v.URL != nil {
+ return v.URL.String()
+ }
+ return ""
+}
+
+func (v URLValue) Set(s string) error {
+ if u, err := url.Parse(s); err != nil {
+ return err
+ } else {
+ *v.URL = *u
+ }
+ return nil
+}
+
+var u = &url.URL{}
+
+func ExampleValue() {
+ fs := flag.NewFlagSet("ExampleValue", flag.ExitOnError)
+ fs.Var(&URLValue{u}, "url", "URL to parse")
+
+ fs.Parse([]string{"-url", "https://golang.org/pkg/flag/"})
+ fmt.Printf(`{scheme: %q, host: %q, path: %q}`, u.Scheme, u.Host, u.Path)
+
+ // Output:
+ // {scheme: "https", host: "golang.org", path: "/pkg/flag/"}
+}
diff --git a/go/src/flag/export_test.go b/go/src/flag/export_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..9ef93ed6c5be1d0ea9949a150b7e92e6b3d59d44
--- /dev/null
+++ b/go/src/flag/export_test.go
@@ -0,0 +1,24 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package flag
+
+import (
+ "io"
+ "os"
+)
+
+// Additional routines compiled into the package only during testing.
+
+var DefaultUsage = Usage
+
+// ResetForTesting clears all flag state and sets the usage function as directed.
+// After calling ResetForTesting, parse errors in flag handling will not
+// exit the program.
+func ResetForTesting(usage func()) {
+ CommandLine = NewFlagSet(os.Args[0], ContinueOnError)
+ CommandLine.SetOutput(io.Discard)
+ CommandLine.Usage = commandLineUsage
+ Usage = usage
+}
diff --git a/go/src/flag/flag.go b/go/src/flag/flag.go
new file mode 100644
index 0000000000000000000000000000000000000000..71902f7f5913e908665dd2c1ab66ea28bce1c36b
--- /dev/null
+++ b/go/src/flag/flag.go
@@ -0,0 +1,1238 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package flag implements command-line flag parsing.
+
+# Usage
+
+Define flags using [flag.String], [Bool], [Int], etc.
+
+This declares an integer flag, -n, stored in the pointer nFlag, with type *int:
+
+ import "flag"
+ var nFlag = flag.Int("n", 1234, "help message for flag n")
+
+If you like, you can bind the flag to a variable using the Var() functions.
+
+ var flagvar int
+ func init() {
+ flag.IntVar(&flagvar, "flagname", 1234, "help message for flagname")
+ }
+
+Or you can create custom flags that satisfy the Value interface (with
+pointer receivers) and couple them to flag parsing by
+
+ flag.Var(&flagVal, "name", "help message for flagname")
+
+For such flags, the default value is just the initial value of the variable.
+
+After all flags are defined, call
+
+ flag.Parse()
+
+to parse the command line into the defined flags.
+
+Flags may then be used directly. If you're using the flags themselves,
+they are all pointers; if you bind to variables, they're values.
+
+ fmt.Println("ip has value ", *ip)
+ fmt.Println("flagvar has value ", flagvar)
+
+After parsing, the arguments following the flags are available as the
+slice [flag.Args] or individually as [flag.Arg](i).
+The arguments are indexed from 0 through [flag.NArg]-1.
+
+# Command line flag syntax
+
+The following forms are permitted:
+
+ -flag
+ --flag // double dashes are also permitted
+ -flag=x
+ -flag x // non-boolean flags only
+
+One or two dashes may be used; they are equivalent.
+The last form is not permitted for boolean flags because the
+meaning of the command
+
+ cmd -x *
+
+where * is a Unix shell wildcard, will change if there is a file
+called 0, false, etc. You must use the -flag=false form to turn
+off a boolean flag.
+
+Flag parsing stops just before the first non-flag argument
+("-" is a non-flag argument) or after the terminator "--".
+
+Integer flags accept 1234, 0664, 0x1234 and may be negative.
+Boolean flags may be:
+
+ 1, 0, t, f, T, F, true, false, TRUE, FALSE, True, False
+
+Duration flags accept any input valid for time.ParseDuration.
+
+The default set of command-line flags is controlled by
+top-level functions. The [FlagSet] type allows one to define
+independent sets of flags, such as to implement subcommands
+in a command-line interface. The methods of [FlagSet] are
+analogous to the top-level functions for the command-line
+flag set.
+*/
+package flag
+
+import (
+ "encoding"
+ "errors"
+ "fmt"
+ "io"
+ "os"
+ "reflect"
+ "runtime"
+ "slices"
+ "strconv"
+ "strings"
+ "time"
+)
+
+// ErrHelp is the error returned if the -help or -h flag is invoked
+// but no such flag is defined.
+var ErrHelp = errors.New("flag: help requested")
+
+// errParse is returned by Set if a flag's value fails to parse, such as with an invalid integer for Int.
+// It then gets wrapped through failf to provide more information.
+var errParse = errors.New("parse error")
+
+// errRange is returned by Set if a flag's value is out of range.
+// It then gets wrapped through failf to provide more information.
+var errRange = errors.New("value out of range")
+
+func numError(err error) error {
+ ne, ok := err.(*strconv.NumError)
+ if !ok {
+ return err
+ }
+ if ne.Err == strconv.ErrSyntax {
+ return errParse
+ }
+ if ne.Err == strconv.ErrRange {
+ return errRange
+ }
+ return err
+}
+
+// -- bool Value
+type boolValue bool
+
+func newBoolValue(val bool, p *bool) *boolValue {
+ *p = val
+ return (*boolValue)(p)
+}
+
+func (b *boolValue) Set(s string) error {
+ v, err := strconv.ParseBool(s)
+ if err != nil {
+ err = errParse
+ }
+ *b = boolValue(v)
+ return err
+}
+
+func (b *boolValue) Get() any { return bool(*b) }
+
+func (b *boolValue) String() string { return strconv.FormatBool(bool(*b)) }
+
+func (b *boolValue) IsBoolFlag() bool { return true }
+
+// optional interface to indicate boolean flags that can be
+// supplied without "=value" text
+type boolFlag interface {
+ Value
+ IsBoolFlag() bool
+}
+
+// -- int Value
+type intValue int
+
+func newIntValue(val int, p *int) *intValue {
+ *p = val
+ return (*intValue)(p)
+}
+
+func (i *intValue) Set(s string) error {
+ v, err := strconv.ParseInt(s, 0, strconv.IntSize)
+ if err != nil {
+ err = numError(err)
+ }
+ *i = intValue(v)
+ return err
+}
+
+func (i *intValue) Get() any { return int(*i) }
+
+func (i *intValue) String() string { return strconv.Itoa(int(*i)) }
+
+// -- int64 Value
+type int64Value int64
+
+func newInt64Value(val int64, p *int64) *int64Value {
+ *p = val
+ return (*int64Value)(p)
+}
+
+func (i *int64Value) Set(s string) error {
+ v, err := strconv.ParseInt(s, 0, 64)
+ if err != nil {
+ err = numError(err)
+ }
+ *i = int64Value(v)
+ return err
+}
+
+func (i *int64Value) Get() any { return int64(*i) }
+
+func (i *int64Value) String() string { return strconv.FormatInt(int64(*i), 10) }
+
+// -- uint Value
+type uintValue uint
+
+func newUintValue(val uint, p *uint) *uintValue {
+ *p = val
+ return (*uintValue)(p)
+}
+
+func (i *uintValue) Set(s string) error {
+ v, err := strconv.ParseUint(s, 0, strconv.IntSize)
+ if err != nil {
+ err = numError(err)
+ }
+ *i = uintValue(v)
+ return err
+}
+
+func (i *uintValue) Get() any { return uint(*i) }
+
+func (i *uintValue) String() string { return strconv.FormatUint(uint64(*i), 10) }
+
+// -- uint64 Value
+type uint64Value uint64
+
+func newUint64Value(val uint64, p *uint64) *uint64Value {
+ *p = val
+ return (*uint64Value)(p)
+}
+
+func (i *uint64Value) Set(s string) error {
+ v, err := strconv.ParseUint(s, 0, 64)
+ if err != nil {
+ err = numError(err)
+ }
+ *i = uint64Value(v)
+ return err
+}
+
+func (i *uint64Value) Get() any { return uint64(*i) }
+
+func (i *uint64Value) String() string { return strconv.FormatUint(uint64(*i), 10) }
+
+// -- string Value
+type stringValue string
+
+func newStringValue(val string, p *string) *stringValue {
+ *p = val
+ return (*stringValue)(p)
+}
+
+func (s *stringValue) Set(val string) error {
+ *s = stringValue(val)
+ return nil
+}
+
+func (s *stringValue) Get() any { return string(*s) }
+
+func (s *stringValue) String() string { return string(*s) }
+
+// -- float64 Value
+type float64Value float64
+
+func newFloat64Value(val float64, p *float64) *float64Value {
+ *p = val
+ return (*float64Value)(p)
+}
+
+func (f *float64Value) Set(s string) error {
+ v, err := strconv.ParseFloat(s, 64)
+ if err != nil {
+ err = numError(err)
+ }
+ *f = float64Value(v)
+ return err
+}
+
+func (f *float64Value) Get() any { return float64(*f) }
+
+func (f *float64Value) String() string { return strconv.FormatFloat(float64(*f), 'g', -1, 64) }
+
+// -- time.Duration Value
+type durationValue time.Duration
+
+func newDurationValue(val time.Duration, p *time.Duration) *durationValue {
+ *p = val
+ return (*durationValue)(p)
+}
+
+func (d *durationValue) Set(s string) error {
+ v, err := time.ParseDuration(s)
+ if err != nil {
+ err = errParse
+ }
+ *d = durationValue(v)
+ return err
+}
+
+func (d *durationValue) Get() any { return time.Duration(*d) }
+
+func (d *durationValue) String() string { return (*time.Duration)(d).String() }
+
+// -- encoding.TextUnmarshaler Value
+type textValue struct{ p encoding.TextUnmarshaler }
+
+func newTextValue(val encoding.TextMarshaler, p encoding.TextUnmarshaler) textValue {
+ ptrVal := reflect.ValueOf(p)
+ if ptrVal.Kind() != reflect.Ptr {
+ panic("variable value type must be a pointer")
+ }
+ defVal := reflect.ValueOf(val)
+ if defVal.Kind() == reflect.Ptr {
+ defVal = defVal.Elem()
+ }
+ if defVal.Type() != ptrVal.Type().Elem() {
+ panic(fmt.Sprintf("default type does not match variable type: %v != %v", defVal.Type(), ptrVal.Type().Elem()))
+ }
+ ptrVal.Elem().Set(defVal)
+ return textValue{p}
+}
+
+func (v textValue) Set(s string) error {
+ return v.p.UnmarshalText([]byte(s))
+}
+
+func (v textValue) Get() any {
+ return v.p
+}
+
+func (v textValue) String() string {
+ if m, ok := v.p.(encoding.TextMarshaler); ok {
+ if b, err := m.MarshalText(); err == nil {
+ return string(b)
+ }
+ }
+ return ""
+}
+
+// -- func Value
+type funcValue func(string) error
+
+func (f funcValue) Set(s string) error { return f(s) }
+
+func (f funcValue) String() string { return "" }
+
+// -- boolFunc Value
+type boolFuncValue func(string) error
+
+func (f boolFuncValue) Set(s string) error { return f(s) }
+
+func (f boolFuncValue) String() string { return "" }
+
+func (f boolFuncValue) IsBoolFlag() bool { return true }
+
+// Value is the interface to the dynamic value stored in a flag.
+// (The default value is represented as a string.)
+//
+// If a Value has an IsBoolFlag() bool method returning true,
+// the command-line parser makes -name equivalent to -name=true
+// rather than using the next command-line argument.
+//
+// Set is called once, in command line order, for each flag present.
+// The flag package may call the [String] method with a zero-valued receiver,
+// such as a nil pointer.
+type Value interface {
+ String() string
+ Set(string) error
+}
+
+// Getter is an interface that allows the contents of a [Value] to be retrieved.
+// It wraps the [Value] interface, rather than being part of it, because it
+// appeared after Go 1 and its compatibility rules. All [Value] types provided
+// by this package satisfy the [Getter] interface, except the type used by [Func].
+type Getter interface {
+ Value
+ Get() any
+}
+
+// ErrorHandling defines how [FlagSet.Parse] behaves if the parse fails.
+type ErrorHandling int
+
+// These constants cause [FlagSet.Parse] to behave as described if the parse fails.
+const (
+ ContinueOnError ErrorHandling = iota // Return a descriptive error.
+ ExitOnError // Call os.Exit(2) or for -h/-help Exit(0).
+ PanicOnError // Call panic with a descriptive error.
+)
+
+// A FlagSet represents a set of defined flags. The zero value of a FlagSet
+// has no name and has [ContinueOnError] error handling.
+//
+// [Flag] names must be unique within a FlagSet. An attempt to define a flag whose
+// name is already in use will cause a panic.
+type FlagSet struct {
+ // Usage is the function called when an error occurs while parsing flags.
+ // The field is a function (not a method) that may be changed to point to
+ // a custom error handler. What happens after Usage is called depends
+ // on the ErrorHandling setting; for the command line, this defaults
+ // to ExitOnError, which exits the program after calling Usage.
+ Usage func()
+
+ name string
+ parsed bool
+ actual map[string]*Flag
+ formal map[string]*Flag
+ args []string // arguments after flags
+ errorHandling ErrorHandling
+ output io.Writer // nil means stderr; use Output() accessor
+ undef map[string]string // flags which didn't exist at the time of Set
+}
+
+// A Flag represents the state of a flag.
+type Flag struct {
+ Name string // name as it appears on command line
+ Usage string // help message
+ Value Value // value as set
+ DefValue string // default value (as text); for usage message
+}
+
+// sortFlags returns the flags as a slice in lexicographical sorted order.
+func sortFlags(flags map[string]*Flag) []*Flag {
+ result := make([]*Flag, len(flags))
+ i := 0
+ for _, f := range flags {
+ result[i] = f
+ i++
+ }
+ slices.SortFunc(result, func(a, b *Flag) int {
+ return strings.Compare(a.Name, b.Name)
+ })
+ return result
+}
+
+// Output returns the destination for usage and error messages. [os.Stderr] is returned if
+// output was not set or was set to nil.
+func (f *FlagSet) Output() io.Writer {
+ if f.output == nil {
+ return os.Stderr
+ }
+ return f.output
+}
+
+// Name returns the name of the flag set.
+func (f *FlagSet) Name() string {
+ return f.name
+}
+
+// ErrorHandling returns the error handling behavior of the flag set.
+func (f *FlagSet) ErrorHandling() ErrorHandling {
+ return f.errorHandling
+}
+
+// SetOutput sets the destination for usage and error messages.
+// If output is nil, [os.Stderr] is used.
+func (f *FlagSet) SetOutput(output io.Writer) {
+ f.output = output
+}
+
+// VisitAll visits the flags in lexicographical order, calling fn for each.
+// It visits all flags, even those not set.
+func (f *FlagSet) VisitAll(fn func(*Flag)) {
+ for _, flag := range sortFlags(f.formal) {
+ fn(flag)
+ }
+}
+
+// VisitAll visits the command-line flags in lexicographical order, calling
+// fn for each. It visits all flags, even those not set.
+func VisitAll(fn func(*Flag)) {
+ CommandLine.VisitAll(fn)
+}
+
+// Visit visits the flags in lexicographical order, calling fn for each.
+// It visits only those flags that have been set.
+func (f *FlagSet) Visit(fn func(*Flag)) {
+ for _, flag := range sortFlags(f.actual) {
+ fn(flag)
+ }
+}
+
+// Visit visits the command-line flags in lexicographical order, calling fn
+// for each. It visits only those flags that have been set.
+func Visit(fn func(*Flag)) {
+ CommandLine.Visit(fn)
+}
+
+// Lookup returns the [Flag] structure of the named flag, returning nil if none exists.
+func (f *FlagSet) Lookup(name string) *Flag {
+ return f.formal[name]
+}
+
+// Lookup returns the [Flag] structure of the named command-line flag,
+// returning nil if none exists.
+func Lookup(name string) *Flag {
+ return CommandLine.formal[name]
+}
+
+// Set sets the value of the named flag.
+func (f *FlagSet) Set(name, value string) error {
+ return f.set(name, value)
+}
+func (f *FlagSet) set(name, value string) error {
+ flag, ok := f.formal[name]
+ if !ok {
+ // Remember that a flag that isn't defined is being set.
+ // We return an error in this case, but in addition if
+ // subsequently that flag is defined, we want to panic
+ // at the definition point.
+ // This is a problem which occurs if both the definition
+ // and the Set call are in init code and for whatever
+ // reason the init code changes evaluation order.
+ // See issue 57411.
+ _, file, line, ok := runtime.Caller(2)
+ if !ok {
+ file = "?"
+ line = 0
+ }
+ if f.undef == nil {
+ f.undef = map[string]string{}
+ }
+ f.undef[name] = fmt.Sprintf("%s:%d", file, line)
+
+ return fmt.Errorf("no such flag -%v", name)
+ }
+ err := flag.Value.Set(value)
+ if err != nil {
+ return err
+ }
+ if f.actual == nil {
+ f.actual = make(map[string]*Flag)
+ }
+ f.actual[name] = flag
+ return nil
+}
+
+// Set sets the value of the named command-line flag.
+func Set(name, value string) error {
+ return CommandLine.set(name, value)
+}
+
+// isZeroValue determines whether the string represents the zero
+// value for a flag.
+func isZeroValue(flag *Flag, value string) (ok bool, err error) {
+ // Build a zero value of the flag's Value type, and see if the
+ // result of calling its String method equals the value passed in.
+ // This works unless the Value type is itself an interface type.
+ typ := reflect.TypeOf(flag.Value)
+ var z reflect.Value
+ if typ.Kind() == reflect.Pointer {
+ z = reflect.New(typ.Elem())
+ } else {
+ z = reflect.Zero(typ)
+ }
+ // Catch panics calling the String method, which shouldn't prevent the
+ // usage message from being printed, but that we should report to the
+ // user so that they know to fix their code.
+ defer func() {
+ if e := recover(); e != nil {
+ if typ.Kind() == reflect.Pointer {
+ typ = typ.Elem()
+ }
+ err = fmt.Errorf("panic calling String method on zero %v for flag %s: %v", typ, flag.Name, e)
+ }
+ }()
+ return value == z.Interface().(Value).String(), nil
+}
+
+// UnquoteUsage extracts a back-quoted name from the usage
+// string for a flag and returns it and the un-quoted usage.
+// Given "a `name` to show" it returns ("name", "a name to show").
+// If there are no back quotes, the name is an educated guess of the
+// type of the flag's value, or the empty string if the flag is boolean.
+func UnquoteUsage(flag *Flag) (name string, usage string) {
+ // Look for a back-quoted name, but avoid the strings package.
+ usage = flag.Usage
+ for i := 0; i < len(usage); i++ {
+ if usage[i] == '`' {
+ for j := i + 1; j < len(usage); j++ {
+ if usage[j] == '`' {
+ name = usage[i+1 : j]
+ usage = usage[:i] + name + usage[j+1:]
+ return name, usage
+ }
+ }
+ break // Only one back quote; use type name.
+ }
+ }
+ // No explicit name, so use type if we can find one.
+ name = "value"
+ switch fv := flag.Value.(type) {
+ case boolFlag:
+ if fv.IsBoolFlag() {
+ name = ""
+ }
+ case *durationValue:
+ name = "duration"
+ case *float64Value:
+ name = "float"
+ case *intValue, *int64Value:
+ name = "int"
+ case *stringValue:
+ name = "string"
+ case *uintValue, *uint64Value:
+ name = "uint"
+ }
+ return
+}
+
+// PrintDefaults prints, to standard error unless configured otherwise, the
+// default values of all defined command-line flags in the set. See the
+// documentation for the global function PrintDefaults for more information.
+func (f *FlagSet) PrintDefaults() {
+ var isZeroValueErrs []error
+ f.VisitAll(func(flag *Flag) {
+ var b strings.Builder
+ fmt.Fprintf(&b, " -%s", flag.Name) // Two spaces before -; see next two comments.
+ name, usage := UnquoteUsage(flag)
+ if len(name) > 0 {
+ b.WriteString(" ")
+ b.WriteString(name)
+ }
+ // Boolean flags of one ASCII letter are so common we
+ // treat them specially, putting their usage on the same line.
+ if b.Len() <= 4 { // space, space, '-', 'x'.
+ b.WriteString("\t")
+ } else {
+ // Four spaces before the tab triggers good alignment
+ // for both 4- and 8-space tab stops.
+ b.WriteString("\n \t")
+ }
+ b.WriteString(strings.ReplaceAll(usage, "\n", "\n \t"))
+
+ // Print the default value only if it differs to the zero value
+ // for this flag type.
+ if isZero, err := isZeroValue(flag, flag.DefValue); err != nil {
+ isZeroValueErrs = append(isZeroValueErrs, err)
+ } else if !isZero {
+ if _, ok := flag.Value.(*stringValue); ok {
+ // put quotes on the value
+ fmt.Fprintf(&b, " (default %q)", flag.DefValue)
+ } else {
+ fmt.Fprintf(&b, " (default %v)", flag.DefValue)
+ }
+ }
+ fmt.Fprint(f.Output(), b.String(), "\n")
+ })
+ // If calling String on any zero flag.Values triggered a panic, print
+ // the messages after the full set of defaults so that the programmer
+ // knows to fix the panic.
+ if errs := isZeroValueErrs; len(errs) > 0 {
+ fmt.Fprintln(f.Output())
+ for _, err := range errs {
+ fmt.Fprintln(f.Output(), err)
+ }
+ }
+}
+
+// PrintDefaults prints, to standard error unless configured otherwise,
+// a usage message showing the default settings of all defined
+// command-line flags.
+// For an integer valued flag x, the default output has the form
+//
+// -x int
+// usage-message-for-x (default 7)
+//
+// The usage message will appear on a separate line for anything but
+// a bool flag with a one-byte name. For bool flags, the type is
+// omitted and if the flag name is one byte the usage message appears
+// on the same line. The parenthetical default is omitted if the
+// default is the zero value for the type. The listed type, here int,
+// can be changed by placing a back-quoted name in the flag's usage
+// string; the first such item in the message is taken to be a parameter
+// name to show in the message and the back quotes are stripped from
+// the message when displayed. For instance, given
+//
+// flag.String("I", "", "search `directory` for include files")
+//
+// the output will be
+//
+// -I directory
+// search directory for include files.
+//
+// To change the destination for flag messages, call [CommandLine].SetOutput.
+func PrintDefaults() {
+ CommandLine.PrintDefaults()
+}
+
+// defaultUsage is the default function to print a usage message.
+func (f *FlagSet) defaultUsage() {
+ if f.name == "" {
+ fmt.Fprintf(f.Output(), "Usage:\n")
+ } else {
+ fmt.Fprintf(f.Output(), "Usage of %s:\n", f.name)
+ }
+ f.PrintDefaults()
+}
+
+// NOTE: Usage is not just defaultUsage(CommandLine)
+// because it serves (via godoc flag Usage) as the example
+// for how to write your own usage function.
+
+// Usage prints a usage message documenting all defined command-line flags
+// to [CommandLine]'s output, which by default is [os.Stderr].
+// It is called when an error occurs while parsing flags.
+// The function is a variable that may be changed to point to a custom function.
+// By default it prints a simple header and calls [PrintDefaults]; for details about the
+// format of the output and how to control it, see the documentation for [PrintDefaults].
+// Custom usage functions may choose to exit the program; by default exiting
+// happens anyway as the command line's error handling strategy is set to
+// [ExitOnError].
+var Usage = func() {
+ fmt.Fprintf(CommandLine.Output(), "Usage of %s:\n", os.Args[0])
+ PrintDefaults()
+}
+
+// NFlag returns the number of flags that have been set.
+func (f *FlagSet) NFlag() int { return len(f.actual) }
+
+// NFlag returns the number of command-line flags that have been set.
+func NFlag() int { return len(CommandLine.actual) }
+
+// Arg returns the i'th argument. Arg(0) is the first remaining argument
+// after flags have been processed. Arg returns an empty string if the
+// requested element does not exist.
+func (f *FlagSet) Arg(i int) string {
+ if i < 0 || i >= len(f.args) {
+ return ""
+ }
+ return f.args[i]
+}
+
+// Arg returns the i'th command-line argument. Arg(0) is the first remaining argument
+// after flags have been processed. Arg returns an empty string if the
+// requested element does not exist.
+func Arg(i int) string {
+ return CommandLine.Arg(i)
+}
+
+// NArg is the number of arguments remaining after flags have been processed.
+func (f *FlagSet) NArg() int { return len(f.args) }
+
+// NArg is the number of arguments remaining after flags have been processed.
+func NArg() int { return len(CommandLine.args) }
+
+// Args returns the non-flag arguments.
+func (f *FlagSet) Args() []string { return f.args }
+
+// Args returns the non-flag command-line arguments.
+func Args() []string { return CommandLine.args }
+
+// BoolVar defines a bool flag with specified name, default value, and usage string.
+// The argument p points to a bool variable in which to store the value of the flag.
+func (f *FlagSet) BoolVar(p *bool, name string, value bool, usage string) {
+ f.Var(newBoolValue(value, p), name, usage)
+}
+
+// BoolVar defines a bool flag with specified name, default value, and usage string.
+// The argument p points to a bool variable in which to store the value of the flag.
+func BoolVar(p *bool, name string, value bool, usage string) {
+ CommandLine.Var(newBoolValue(value, p), name, usage)
+}
+
+// Bool defines a bool flag with specified name, default value, and usage string.
+// The return value is the address of a bool variable that stores the value of the flag.
+func (f *FlagSet) Bool(name string, value bool, usage string) *bool {
+ p := new(bool)
+ f.BoolVar(p, name, value, usage)
+ return p
+}
+
+// Bool defines a bool flag with specified name, default value, and usage string.
+// The return value is the address of a bool variable that stores the value of the flag.
+func Bool(name string, value bool, usage string) *bool {
+ return CommandLine.Bool(name, value, usage)
+}
+
+// IntVar defines an int flag with specified name, default value, and usage string.
+// The argument p points to an int variable in which to store the value of the flag.
+func (f *FlagSet) IntVar(p *int, name string, value int, usage string) {
+ f.Var(newIntValue(value, p), name, usage)
+}
+
+// IntVar defines an int flag with specified name, default value, and usage string.
+// The argument p points to an int variable in which to store the value of the flag.
+func IntVar(p *int, name string, value int, usage string) {
+ CommandLine.Var(newIntValue(value, p), name, usage)
+}
+
+// Int defines an int flag with specified name, default value, and usage string.
+// The return value is the address of an int variable that stores the value of the flag.
+func (f *FlagSet) Int(name string, value int, usage string) *int {
+ p := new(int)
+ f.IntVar(p, name, value, usage)
+ return p
+}
+
+// Int defines an int flag with specified name, default value, and usage string.
+// The return value is the address of an int variable that stores the value of the flag.
+func Int(name string, value int, usage string) *int {
+ return CommandLine.Int(name, value, usage)
+}
+
+// Int64Var defines an int64 flag with specified name, default value, and usage string.
+// The argument p points to an int64 variable in which to store the value of the flag.
+func (f *FlagSet) Int64Var(p *int64, name string, value int64, usage string) {
+ f.Var(newInt64Value(value, p), name, usage)
+}
+
+// Int64Var defines an int64 flag with specified name, default value, and usage string.
+// The argument p points to an int64 variable in which to store the value of the flag.
+func Int64Var(p *int64, name string, value int64, usage string) {
+ CommandLine.Var(newInt64Value(value, p), name, usage)
+}
+
+// Int64 defines an int64 flag with specified name, default value, and usage string.
+// The return value is the address of an int64 variable that stores the value of the flag.
+func (f *FlagSet) Int64(name string, value int64, usage string) *int64 {
+ p := new(int64)
+ f.Int64Var(p, name, value, usage)
+ return p
+}
+
+// Int64 defines an int64 flag with specified name, default value, and usage string.
+// The return value is the address of an int64 variable that stores the value of the flag.
+func Int64(name string, value int64, usage string) *int64 {
+ return CommandLine.Int64(name, value, usage)
+}
+
+// UintVar defines a uint flag with specified name, default value, and usage string.
+// The argument p points to a uint variable in which to store the value of the flag.
+func (f *FlagSet) UintVar(p *uint, name string, value uint, usage string) {
+ f.Var(newUintValue(value, p), name, usage)
+}
+
+// UintVar defines a uint flag with specified name, default value, and usage string.
+// The argument p points to a uint variable in which to store the value of the flag.
+func UintVar(p *uint, name string, value uint, usage string) {
+ CommandLine.Var(newUintValue(value, p), name, usage)
+}
+
+// Uint defines a uint flag with specified name, default value, and usage string.
+// The return value is the address of a uint variable that stores the value of the flag.
+func (f *FlagSet) Uint(name string, value uint, usage string) *uint {
+ p := new(uint)
+ f.UintVar(p, name, value, usage)
+ return p
+}
+
+// Uint defines a uint flag with specified name, default value, and usage string.
+// The return value is the address of a uint variable that stores the value of the flag.
+func Uint(name string, value uint, usage string) *uint {
+ return CommandLine.Uint(name, value, usage)
+}
+
+// Uint64Var defines a uint64 flag with specified name, default value, and usage string.
+// The argument p points to a uint64 variable in which to store the value of the flag.
+func (f *FlagSet) Uint64Var(p *uint64, name string, value uint64, usage string) {
+ f.Var(newUint64Value(value, p), name, usage)
+}
+
+// Uint64Var defines a uint64 flag with specified name, default value, and usage string.
+// The argument p points to a uint64 variable in which to store the value of the flag.
+func Uint64Var(p *uint64, name string, value uint64, usage string) {
+ CommandLine.Var(newUint64Value(value, p), name, usage)
+}
+
+// Uint64 defines a uint64 flag with specified name, default value, and usage string.
+// The return value is the address of a uint64 variable that stores the value of the flag.
+func (f *FlagSet) Uint64(name string, value uint64, usage string) *uint64 {
+ p := new(uint64)
+ f.Uint64Var(p, name, value, usage)
+ return p
+}
+
+// Uint64 defines a uint64 flag with specified name, default value, and usage string.
+// The return value is the address of a uint64 variable that stores the value of the flag.
+func Uint64(name string, value uint64, usage string) *uint64 {
+ return CommandLine.Uint64(name, value, usage)
+}
+
+// StringVar defines a string flag with specified name, default value, and usage string.
+// The argument p points to a string variable in which to store the value of the flag.
+func (f *FlagSet) StringVar(p *string, name string, value string, usage string) {
+ f.Var(newStringValue(value, p), name, usage)
+}
+
+// StringVar defines a string flag with specified name, default value, and usage string.
+// The argument p points to a string variable in which to store the value of the flag.
+func StringVar(p *string, name string, value string, usage string) {
+ CommandLine.Var(newStringValue(value, p), name, usage)
+}
+
+// String defines a string flag with specified name, default value, and usage string.
+// The return value is the address of a string variable that stores the value of the flag.
+func (f *FlagSet) String(name string, value string, usage string) *string {
+ p := new(string)
+ f.StringVar(p, name, value, usage)
+ return p
+}
+
+// String defines a string flag with specified name, default value, and usage string.
+// The return value is the address of a string variable that stores the value of the flag.
+func String(name string, value string, usage string) *string {
+ return CommandLine.String(name, value, usage)
+}
+
+// Float64Var defines a float64 flag with specified name, default value, and usage string.
+// The argument p points to a float64 variable in which to store the value of the flag.
+func (f *FlagSet) Float64Var(p *float64, name string, value float64, usage string) {
+ f.Var(newFloat64Value(value, p), name, usage)
+}
+
+// Float64Var defines a float64 flag with specified name, default value, and usage string.
+// The argument p points to a float64 variable in which to store the value of the flag.
+func Float64Var(p *float64, name string, value float64, usage string) {
+ CommandLine.Var(newFloat64Value(value, p), name, usage)
+}
+
+// Float64 defines a float64 flag with specified name, default value, and usage string.
+// The return value is the address of a float64 variable that stores the value of the flag.
+func (f *FlagSet) Float64(name string, value float64, usage string) *float64 {
+ p := new(float64)
+ f.Float64Var(p, name, value, usage)
+ return p
+}
+
+// Float64 defines a float64 flag with specified name, default value, and usage string.
+// The return value is the address of a float64 variable that stores the value of the flag.
+func Float64(name string, value float64, usage string) *float64 {
+ return CommandLine.Float64(name, value, usage)
+}
+
+// DurationVar defines a time.Duration flag with specified name, default value, and usage string.
+// The argument p points to a time.Duration variable in which to store the value of the flag.
+// The flag accepts a value acceptable to time.ParseDuration.
+func (f *FlagSet) DurationVar(p *time.Duration, name string, value time.Duration, usage string) {
+ f.Var(newDurationValue(value, p), name, usage)
+}
+
+// DurationVar defines a time.Duration flag with specified name, default value, and usage string.
+// The argument p points to a time.Duration variable in which to store the value of the flag.
+// The flag accepts a value acceptable to time.ParseDuration.
+func DurationVar(p *time.Duration, name string, value time.Duration, usage string) {
+ CommandLine.Var(newDurationValue(value, p), name, usage)
+}
+
+// Duration defines a time.Duration flag with specified name, default value, and usage string.
+// The return value is the address of a time.Duration variable that stores the value of the flag.
+// The flag accepts a value acceptable to time.ParseDuration.
+func (f *FlagSet) Duration(name string, value time.Duration, usage string) *time.Duration {
+ p := new(time.Duration)
+ f.DurationVar(p, name, value, usage)
+ return p
+}
+
+// Duration defines a time.Duration flag with specified name, default value, and usage string.
+// The return value is the address of a time.Duration variable that stores the value of the flag.
+// The flag accepts a value acceptable to time.ParseDuration.
+func Duration(name string, value time.Duration, usage string) *time.Duration {
+ return CommandLine.Duration(name, value, usage)
+}
+
+// TextVar defines a flag with a specified name, default value, and usage string.
+// The argument p must be a pointer to a variable that will hold the value
+// of the flag, and p must implement encoding.TextUnmarshaler.
+// If the flag is used, the flag value will be passed to p's UnmarshalText method.
+// The type of the default value must be the same as the type of p.
+func (f *FlagSet) TextVar(p encoding.TextUnmarshaler, name string, value encoding.TextMarshaler, usage string) {
+ f.Var(newTextValue(value, p), name, usage)
+}
+
+// TextVar defines a flag with a specified name, default value, and usage string.
+// The argument p must be a pointer to a variable that will hold the value
+// of the flag, and p must implement encoding.TextUnmarshaler.
+// If the flag is used, the flag value will be passed to p's UnmarshalText method.
+// The type of the default value must be the same as the type of p.
+func TextVar(p encoding.TextUnmarshaler, name string, value encoding.TextMarshaler, usage string) {
+ CommandLine.Var(newTextValue(value, p), name, usage)
+}
+
+// Func defines a flag with the specified name and usage string.
+// Each time the flag is seen, fn is called with the value of the flag.
+// If fn returns a non-nil error, it will be treated as a flag value parsing error.
+func (f *FlagSet) Func(name, usage string, fn func(string) error) {
+ f.Var(funcValue(fn), name, usage)
+}
+
+// Func defines a flag with the specified name and usage string.
+// Each time the flag is seen, fn is called with the value of the flag.
+// If fn returns a non-nil error, it will be treated as a flag value parsing error.
+func Func(name, usage string, fn func(string) error) {
+ CommandLine.Func(name, usage, fn)
+}
+
+// BoolFunc defines a flag with the specified name and usage string without requiring values.
+// Each time the flag is seen, fn is called with the value of the flag.
+// If fn returns a non-nil error, it will be treated as a flag value parsing error.
+func (f *FlagSet) BoolFunc(name, usage string, fn func(string) error) {
+ f.Var(boolFuncValue(fn), name, usage)
+}
+
+// BoolFunc defines a flag with the specified name and usage string without requiring values.
+// Each time the flag is seen, fn is called with the value of the flag.
+// If fn returns a non-nil error, it will be treated as a flag value parsing error.
+func BoolFunc(name, usage string, fn func(string) error) {
+ CommandLine.BoolFunc(name, usage, fn)
+}
+
+// Var defines a flag with the specified name and usage string. The type and
+// value of the flag are represented by the first argument, of type [Value], which
+// typically holds a user-defined implementation of [Value]. For instance, the
+// caller could create a flag that turns a comma-separated string into a slice
+// of strings by giving the slice the methods of [Value]; in particular, [Set] would
+// decompose the comma-separated string into the slice.
+func (f *FlagSet) Var(value Value, name string, usage string) {
+ // Flag must not begin "-" or contain "=".
+ if strings.HasPrefix(name, "-") {
+ panic(f.sprintf("flag %q begins with -", name))
+ } else if strings.Contains(name, "=") {
+ panic(f.sprintf("flag %q contains =", name))
+ }
+
+ // Remember the default value as a string; it won't change.
+ flag := &Flag{name, usage, value, value.String()}
+ _, alreadythere := f.formal[name]
+ if alreadythere {
+ var msg string
+ if f.name == "" {
+ msg = f.sprintf("flag redefined: %s", name)
+ } else {
+ msg = f.sprintf("%s flag redefined: %s", f.name, name)
+ }
+ panic(msg) // Happens only if flags are declared with identical names
+ }
+ if pos := f.undef[name]; pos != "" {
+ panic(fmt.Sprintf("flag %s set at %s before being defined", name, pos))
+ }
+ if f.formal == nil {
+ f.formal = make(map[string]*Flag)
+ }
+ f.formal[name] = flag
+}
+
+// Var defines a flag with the specified name and usage string. The type and
+// value of the flag are represented by the first argument, of type [Value], which
+// typically holds a user-defined implementation of [Value]. For instance, the
+// caller could create a flag that turns a comma-separated string into a slice
+// of strings by giving the slice the methods of [Value]; in particular, [Set] would
+// decompose the comma-separated string into the slice.
+func Var(value Value, name string, usage string) {
+ CommandLine.Var(value, name, usage)
+}
+
+// sprintf formats the message, prints it to output, and returns it.
+func (f *FlagSet) sprintf(format string, a ...any) string {
+ msg := fmt.Sprintf(format, a...)
+ fmt.Fprintln(f.Output(), msg)
+ return msg
+}
+
+// failf prints to standard error a formatted error and usage message and
+// returns the error.
+func (f *FlagSet) failf(format string, a ...any) error {
+ msg := f.sprintf(format, a...)
+ f.usage()
+ return errors.New(msg)
+}
+
+// usage calls the Usage method for the flag set if one is specified,
+// or the appropriate default usage function otherwise.
+func (f *FlagSet) usage() {
+ if f.Usage == nil {
+ f.defaultUsage()
+ } else {
+ f.Usage()
+ }
+}
+
+// parseOne parses one flag. It reports whether a flag was seen.
+func (f *FlagSet) parseOne() (bool, error) {
+ if len(f.args) == 0 {
+ return false, nil
+ }
+ s := f.args[0]
+ if len(s) < 2 || s[0] != '-' {
+ return false, nil
+ }
+ numMinuses := 1
+ if s[1] == '-' {
+ numMinuses++
+ if len(s) == 2 { // "--" terminates the flags
+ f.args = f.args[1:]
+ return false, nil
+ }
+ }
+ name := s[numMinuses:]
+ if len(name) == 0 || name[0] == '-' || name[0] == '=' {
+ return false, f.failf("bad flag syntax: %s", s)
+ }
+
+ // it's a flag. does it have an argument?
+ f.args = f.args[1:]
+ hasValue := false
+ value := ""
+ for i := 1; i < len(name); i++ { // equals cannot be first
+ if name[i] == '=' {
+ value = name[i+1:]
+ hasValue = true
+ name = name[0:i]
+ break
+ }
+ }
+
+ flag, ok := f.formal[name]
+ if !ok {
+ if name == "help" || name == "h" { // special case for nice help message.
+ f.usage()
+ return false, ErrHelp
+ }
+ return false, f.failf("flag provided but not defined: -%s", name)
+ }
+
+ if fv, ok := flag.Value.(boolFlag); ok && fv.IsBoolFlag() { // special case: doesn't need an arg
+ if hasValue {
+ if err := fv.Set(value); err != nil {
+ return false, f.failf("invalid boolean value %q for -%s: %v", value, name, err)
+ }
+ } else {
+ if err := fv.Set("true"); err != nil {
+ return false, f.failf("invalid boolean flag %s: %v", name, err)
+ }
+ }
+ } else {
+ // It must have a value, which might be the next argument.
+ if !hasValue && len(f.args) > 0 {
+ // value is the next arg
+ hasValue = true
+ value, f.args = f.args[0], f.args[1:]
+ }
+ if !hasValue {
+ return false, f.failf("flag needs an argument: -%s", name)
+ }
+ if err := flag.Value.Set(value); err != nil {
+ return false, f.failf("invalid value %q for flag -%s: %v", value, name, err)
+ }
+ }
+ if f.actual == nil {
+ f.actual = make(map[string]*Flag)
+ }
+ f.actual[name] = flag
+ return true, nil
+}
+
+// Parse parses flag definitions from the argument list, which should not
+// include the command name. Must be called after all flags in the [FlagSet]
+// are defined and before flags are accessed by the program.
+// The return value will be [ErrHelp] if -help or -h were set but not defined.
+func (f *FlagSet) Parse(arguments []string) error {
+ f.parsed = true
+ f.args = arguments
+ for {
+ seen, err := f.parseOne()
+ if seen {
+ continue
+ }
+ if err == nil {
+ break
+ }
+ switch f.errorHandling {
+ case ContinueOnError:
+ return err
+ case ExitOnError:
+ if err == ErrHelp {
+ os.Exit(0)
+ }
+ os.Exit(2)
+ case PanicOnError:
+ panic(err)
+ }
+ }
+ return nil
+}
+
+// Parsed reports whether f.Parse has been called.
+func (f *FlagSet) Parsed() bool {
+ return f.parsed
+}
+
+// Parse parses the command-line flags from [os.Args][1:]. Must be called
+// after all flags are defined and before flags are accessed by the program.
+func Parse() {
+ // Ignore errors; CommandLine is set for ExitOnError.
+ CommandLine.Parse(os.Args[1:])
+}
+
+// Parsed reports whether the command-line flags have been parsed.
+func Parsed() bool {
+ return CommandLine.Parsed()
+}
+
+// CommandLine is the default set of command-line flags, parsed from [os.Args].
+// The top-level functions such as [BoolVar], [Arg], and so on are wrappers for the
+// methods of CommandLine.
+var CommandLine *FlagSet
+
+func init() {
+ // It's possible for execl to hand us an empty os.Args.
+ if len(os.Args) == 0 {
+ CommandLine = NewFlagSet("", ExitOnError)
+ } else {
+ CommandLine = NewFlagSet(os.Args[0], ExitOnError)
+ }
+
+ // Override generic FlagSet default Usage with call to global Usage.
+ // Note: This is not CommandLine.Usage = Usage,
+ // because we want any eventual call to use any updated value of Usage,
+ // not the value it has when this line is run.
+ CommandLine.Usage = commandLineUsage
+}
+
+func commandLineUsage() {
+ Usage()
+}
+
+// NewFlagSet returns a new, empty flag set with the specified name and
+// error handling property. If the name is not empty, it will be printed
+// in the default usage message and in error messages.
+func NewFlagSet(name string, errorHandling ErrorHandling) *FlagSet {
+ f := &FlagSet{
+ name: name,
+ errorHandling: errorHandling,
+ }
+ f.Usage = f.defaultUsage
+ return f
+}
+
+// Init sets the name and error handling property for a flag set.
+// By default, the zero [FlagSet] uses an empty name and the
+// [ContinueOnError] error handling policy.
+func (f *FlagSet) Init(name string, errorHandling ErrorHandling) {
+ f.name = name
+ f.errorHandling = errorHandling
+}
diff --git a/go/src/flag/flag_test.go b/go/src/flag/flag_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..278ae7e4e02aac1abf279e6764af7a20390051af
--- /dev/null
+++ b/go/src/flag/flag_test.go
@@ -0,0 +1,858 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package flag_test
+
+import (
+ "bytes"
+ . "flag"
+ "fmt"
+ "internal/testenv"
+ "io"
+ "os"
+ "os/exec"
+ "regexp"
+ "runtime"
+ "slices"
+ "strconv"
+ "strings"
+ "testing"
+ "time"
+)
+
+func boolString(s string) string {
+ if s == "0" {
+ return "false"
+ }
+ return "true"
+}
+
+func TestEverything(t *testing.T) {
+ ResetForTesting(nil)
+ Bool("test_bool", false, "bool value")
+ Int("test_int", 0, "int value")
+ Int64("test_int64", 0, "int64 value")
+ Uint("test_uint", 0, "uint value")
+ Uint64("test_uint64", 0, "uint64 value")
+ String("test_string", "0", "string value")
+ Float64("test_float64", 0, "float64 value")
+ Duration("test_duration", 0, "time.Duration value")
+ Func("test_func", "func value", func(string) error { return nil })
+ BoolFunc("test_boolfunc", "func", func(string) error { return nil })
+
+ m := make(map[string]*Flag)
+ desired := "0"
+ visitor := func(f *Flag) {
+ if len(f.Name) > 5 && f.Name[0:5] == "test_" {
+ m[f.Name] = f
+ ok := false
+ switch {
+ case f.Value.String() == desired:
+ ok = true
+ case f.Name == "test_bool" && f.Value.String() == boolString(desired):
+ ok = true
+ case f.Name == "test_duration" && f.Value.String() == desired+"s":
+ ok = true
+ case f.Name == "test_func" && f.Value.String() == "":
+ ok = true
+ case f.Name == "test_boolfunc" && f.Value.String() == "":
+ ok = true
+ }
+ if !ok {
+ t.Error("Visit: bad value", f.Value.String(), "for", f.Name)
+ }
+ }
+ }
+ VisitAll(visitor)
+ if len(m) != 10 {
+ t.Error("VisitAll misses some flags")
+ for k, v := range m {
+ t.Log(k, *v)
+ }
+ }
+ m = make(map[string]*Flag)
+ Visit(visitor)
+ if len(m) != 0 {
+ t.Errorf("Visit sees unset flags")
+ for k, v := range m {
+ t.Log(k, *v)
+ }
+ }
+ // Now set all flags
+ Set("test_bool", "true")
+ Set("test_int", "1")
+ Set("test_int64", "1")
+ Set("test_uint", "1")
+ Set("test_uint64", "1")
+ Set("test_string", "1")
+ Set("test_float64", "1")
+ Set("test_duration", "1s")
+ Set("test_func", "1")
+ Set("test_boolfunc", "")
+ desired = "1"
+ Visit(visitor)
+ if len(m) != 10 {
+ t.Error("Visit fails after set")
+ for k, v := range m {
+ t.Log(k, *v)
+ }
+ }
+ // Now test they're visited in sort order.
+ var flagNames []string
+ Visit(func(f *Flag) { flagNames = append(flagNames, f.Name) })
+ if !slices.IsSorted(flagNames) {
+ t.Errorf("flag names not sorted: %v", flagNames)
+ }
+}
+
+func TestGet(t *testing.T) {
+ ResetForTesting(nil)
+ Bool("test_bool", true, "bool value")
+ Int("test_int", 1, "int value")
+ Int64("test_int64", 2, "int64 value")
+ Uint("test_uint", 3, "uint value")
+ Uint64("test_uint64", 4, "uint64 value")
+ String("test_string", "5", "string value")
+ Float64("test_float64", 6, "float64 value")
+ Duration("test_duration", 7, "time.Duration value")
+
+ visitor := func(f *Flag) {
+ if len(f.Name) > 5 && f.Name[0:5] == "test_" {
+ g, ok := f.Value.(Getter)
+ if !ok {
+ t.Errorf("Visit: value does not satisfy Getter: %T", f.Value)
+ return
+ }
+ switch f.Name {
+ case "test_bool":
+ ok = g.Get() == true
+ case "test_int":
+ ok = g.Get() == int(1)
+ case "test_int64":
+ ok = g.Get() == int64(2)
+ case "test_uint":
+ ok = g.Get() == uint(3)
+ case "test_uint64":
+ ok = g.Get() == uint64(4)
+ case "test_string":
+ ok = g.Get() == "5"
+ case "test_float64":
+ ok = g.Get() == float64(6)
+ case "test_duration":
+ ok = g.Get() == time.Duration(7)
+ }
+ if !ok {
+ t.Errorf("Visit: bad value %T(%v) for %s", g.Get(), g.Get(), f.Name)
+ }
+ }
+ }
+ VisitAll(visitor)
+}
+
+func TestUsage(t *testing.T) {
+ called := false
+ ResetForTesting(func() { called = true })
+ if CommandLine.Parse([]string{"-x"}) == nil {
+ t.Error("parse did not fail for unknown flag")
+ }
+ if !called {
+ t.Error("did not call Usage for unknown flag")
+ }
+}
+
+func testParse(f *FlagSet, t *testing.T) {
+ if f.Parsed() {
+ t.Error("f.Parse() = true before Parse")
+ }
+ boolFlag := f.Bool("bool", false, "bool value")
+ bool2Flag := f.Bool("bool2", false, "bool2 value")
+ intFlag := f.Int("int", 0, "int value")
+ int64Flag := f.Int64("int64", 0, "int64 value")
+ uintFlag := f.Uint("uint", 0, "uint value")
+ uint64Flag := f.Uint64("uint64", 0, "uint64 value")
+ stringFlag := f.String("string", "0", "string value")
+ float64Flag := f.Float64("float64", 0, "float64 value")
+ durationFlag := f.Duration("duration", 5*time.Second, "time.Duration value")
+ extra := "one-extra-argument"
+ args := []string{
+ "-bool",
+ "-bool2=true",
+ "--int", "22",
+ "--int64", "0x23",
+ "-uint", "24",
+ "--uint64", "25",
+ "-string", "hello",
+ "-float64", "2718e28",
+ "-duration", "2m",
+ extra,
+ }
+ if err := f.Parse(args); err != nil {
+ t.Fatal(err)
+ }
+ if !f.Parsed() {
+ t.Error("f.Parse() = false after Parse")
+ }
+ if *boolFlag != true {
+ t.Error("bool flag should be true, is ", *boolFlag)
+ }
+ if *bool2Flag != true {
+ t.Error("bool2 flag should be true, is ", *bool2Flag)
+ }
+ if *intFlag != 22 {
+ t.Error("int flag should be 22, is ", *intFlag)
+ }
+ if *int64Flag != 0x23 {
+ t.Error("int64 flag should be 0x23, is ", *int64Flag)
+ }
+ if *uintFlag != 24 {
+ t.Error("uint flag should be 24, is ", *uintFlag)
+ }
+ if *uint64Flag != 25 {
+ t.Error("uint64 flag should be 25, is ", *uint64Flag)
+ }
+ if *stringFlag != "hello" {
+ t.Error("string flag should be `hello`, is ", *stringFlag)
+ }
+ if *float64Flag != 2718e28 {
+ t.Error("float64 flag should be 2718e28, is ", *float64Flag)
+ }
+ if *durationFlag != 2*time.Minute {
+ t.Error("duration flag should be 2m, is ", *durationFlag)
+ }
+ if len(f.Args()) != 1 {
+ t.Error("expected one argument, got", len(f.Args()))
+ } else if f.Args()[0] != extra {
+ t.Errorf("expected argument %q got %q", extra, f.Args()[0])
+ }
+}
+
+func TestParse(t *testing.T) {
+ ResetForTesting(func() { t.Error("bad parse") })
+ testParse(CommandLine, t)
+}
+
+func TestFlagSetParse(t *testing.T) {
+ testParse(NewFlagSet("test", ContinueOnError), t)
+}
+
+// Declare a user-defined flag type.
+type flagVar []string
+
+func (f *flagVar) String() string {
+ return fmt.Sprint([]string(*f))
+}
+
+func (f *flagVar) Set(value string) error {
+ *f = append(*f, value)
+ return nil
+}
+
+func TestUserDefined(t *testing.T) {
+ var flags FlagSet
+ flags.Init("test", ContinueOnError)
+ flags.SetOutput(io.Discard)
+ var v flagVar
+ flags.Var(&v, "v", "usage")
+ if err := flags.Parse([]string{"-v", "1", "-v", "2", "-v=3"}); err != nil {
+ t.Error(err)
+ }
+ if len(v) != 3 {
+ t.Fatal("expected 3 args; got ", len(v))
+ }
+ expect := "[1 2 3]"
+ if v.String() != expect {
+ t.Errorf("expected value %q got %q", expect, v.String())
+ }
+}
+
+func TestUserDefinedFunc(t *testing.T) {
+ flags := NewFlagSet("test", ContinueOnError)
+ flags.SetOutput(io.Discard)
+ var ss []string
+ flags.Func("v", "usage", func(s string) error {
+ ss = append(ss, s)
+ return nil
+ })
+ if err := flags.Parse([]string{"-v", "1", "-v", "2", "-v=3"}); err != nil {
+ t.Error(err)
+ }
+ if len(ss) != 3 {
+ t.Fatal("expected 3 args; got ", len(ss))
+ }
+ expect := "[1 2 3]"
+ if got := fmt.Sprint(ss); got != expect {
+ t.Errorf("expected value %q got %q", expect, got)
+ }
+ // test usage
+ var buf strings.Builder
+ flags.SetOutput(&buf)
+ flags.Parse([]string{"-h"})
+ if usage := buf.String(); !strings.Contains(usage, "usage") {
+ t.Errorf("usage string not included: %q", usage)
+ }
+ // test Func error
+ flags = NewFlagSet("test", ContinueOnError)
+ flags.SetOutput(io.Discard)
+ flags.Func("v", "usage", func(s string) error {
+ return fmt.Errorf("test error")
+ })
+ // flag not set, so no error
+ if err := flags.Parse(nil); err != nil {
+ t.Error(err)
+ }
+ // flag set, expect error
+ if err := flags.Parse([]string{"-v", "1"}); err == nil {
+ t.Error("expected error; got none")
+ } else if errMsg := err.Error(); !strings.Contains(errMsg, "test error") {
+ t.Errorf(`error should contain "test error"; got %q`, errMsg)
+ }
+}
+
+func TestUserDefinedForCommandLine(t *testing.T) {
+ const help = "HELP"
+ var result string
+ ResetForTesting(func() { result = help })
+ Usage()
+ if result != help {
+ t.Fatalf("got %q; expected %q", result, help)
+ }
+}
+
+// Declare a user-defined boolean flag type.
+type boolFlagVar struct {
+ count int
+}
+
+func (b *boolFlagVar) String() string {
+ return fmt.Sprintf("%d", b.count)
+}
+
+func (b *boolFlagVar) Set(value string) error {
+ if value == "true" {
+ b.count++
+ }
+ return nil
+}
+
+func (b *boolFlagVar) IsBoolFlag() bool {
+ return b.count < 4
+}
+
+func TestUserDefinedBool(t *testing.T) {
+ var flags FlagSet
+ flags.Init("test", ContinueOnError)
+ flags.SetOutput(io.Discard)
+ var b boolFlagVar
+ var err error
+ flags.Var(&b, "b", "usage")
+ if err = flags.Parse([]string{"-b", "-b", "-b", "-b=true", "-b=false", "-b", "barg", "-b"}); err != nil {
+ if b.count < 4 {
+ t.Error(err)
+ }
+ }
+
+ if b.count != 4 {
+ t.Errorf("want: %d; got: %d", 4, b.count)
+ }
+
+ if err == nil {
+ t.Error("expected error; got none")
+ }
+}
+
+func TestUserDefinedBoolUsage(t *testing.T) {
+ var flags FlagSet
+ flags.Init("test", ContinueOnError)
+ var buf bytes.Buffer
+ flags.SetOutput(&buf)
+ var b boolFlagVar
+ flags.Var(&b, "b", "X")
+ b.count = 0
+ // b.IsBoolFlag() will return true and usage will look boolean.
+ flags.PrintDefaults()
+ got := buf.String()
+ want := " -b\tX\n"
+ if got != want {
+ t.Errorf("false: want %q; got %q", want, got)
+ }
+ b.count = 4
+ // b.IsBoolFlag() will return false and usage will look non-boolean.
+ flags.PrintDefaults()
+ got = buf.String()
+ want = " -b\tX\n -b value\n \tX\n"
+ if got != want {
+ t.Errorf("false: want %q; got %q", want, got)
+ }
+}
+
+func TestSetOutput(t *testing.T) {
+ var flags FlagSet
+ var buf strings.Builder
+ flags.SetOutput(&buf)
+ flags.Init("test", ContinueOnError)
+ flags.Parse([]string{"-unknown"})
+ if out := buf.String(); !strings.Contains(out, "-unknown") {
+ t.Logf("expected output mentioning unknown; got %q", out)
+ }
+}
+
+// This tests that one can reset the flags. This still works but not well, and is
+// superseded by FlagSet.
+func TestChangingArgs(t *testing.T) {
+ ResetForTesting(func() { t.Fatal("bad parse") })
+ oldArgs := os.Args
+ defer func() { os.Args = oldArgs }()
+ os.Args = []string{"cmd", "-before", "subcmd", "-after", "args"}
+ before := Bool("before", false, "")
+ if err := CommandLine.Parse(os.Args[1:]); err != nil {
+ t.Fatal(err)
+ }
+ cmd := Arg(0)
+ os.Args = Args()
+ after := Bool("after", false, "")
+ Parse()
+ args := Args()
+
+ if !*before || cmd != "subcmd" || !*after || len(args) != 1 || args[0] != "args" {
+ t.Fatalf("expected true subcmd true [args] got %v %v %v %v", *before, cmd, *after, args)
+ }
+}
+
+// Test that -help invokes the usage message and returns ErrHelp.
+func TestHelp(t *testing.T) {
+ var helpCalled = false
+ fs := NewFlagSet("help test", ContinueOnError)
+ fs.Usage = func() { helpCalled = true }
+ var flag bool
+ fs.BoolVar(&flag, "flag", false, "regular flag")
+ // Regular flag invocation should work
+ err := fs.Parse([]string{"-flag=true"})
+ if err != nil {
+ t.Fatal("expected no error; got ", err)
+ }
+ if !flag {
+ t.Error("flag was not set by -flag")
+ }
+ if helpCalled {
+ t.Error("help called for regular flag")
+ helpCalled = false // reset for next test
+ }
+ // Help flag should work as expected.
+ err = fs.Parse([]string{"-help"})
+ if err == nil {
+ t.Fatal("error expected")
+ }
+ if err != ErrHelp {
+ t.Fatal("expected ErrHelp; got ", err)
+ }
+ if !helpCalled {
+ t.Fatal("help was not called")
+ }
+ // If we define a help flag, that should override.
+ var help bool
+ fs.BoolVar(&help, "help", false, "help flag")
+ helpCalled = false
+ err = fs.Parse([]string{"-help"})
+ if err != nil {
+ t.Fatal("expected no error for defined -help; got ", err)
+ }
+ if helpCalled {
+ t.Fatal("help was called; should not have been for defined help flag")
+ }
+}
+
+// zeroPanicker is a flag.Value whose String method panics if its dontPanic
+// field is false.
+type zeroPanicker struct {
+ dontPanic bool
+ v string
+}
+
+func (f *zeroPanicker) Set(s string) error {
+ f.v = s
+ return nil
+}
+
+func (f *zeroPanicker) String() string {
+ if !f.dontPanic {
+ panic("panic!")
+ }
+ return f.v
+}
+
+const defaultOutput = ` -A for bootstrapping, allow 'any' type
+ -Alongflagname
+ disable bounds checking
+ -C a boolean defaulting to true (default true)
+ -D path
+ set relative path for local imports
+ -E string
+ issue 23543 (default "0")
+ -F number
+ a non-zero number (default 2.7)
+ -G float
+ a float that defaults to zero
+ -M string
+ a multiline
+ help
+ string
+ -N int
+ a non-zero int (default 27)
+ -O a flag
+ multiline help string (default true)
+ -V list
+ a list of strings (default [a b])
+ -Z int
+ an int that defaults to zero
+ -ZP0 value
+ a flag whose String method panics when it is zero
+ -ZP1 value
+ a flag whose String method panics when it is zero
+ -maxT timeout
+ set timeout for dial
+
+panic calling String method on zero flag_test.zeroPanicker for flag ZP0: panic!
+panic calling String method on zero flag_test.zeroPanicker for flag ZP1: panic!
+`
+
+func TestPrintDefaults(t *testing.T) {
+ fs := NewFlagSet("print defaults test", ContinueOnError)
+ var buf strings.Builder
+ fs.SetOutput(&buf)
+ fs.Bool("A", false, "for bootstrapping, allow 'any' type")
+ fs.Bool("Alongflagname", false, "disable bounds checking")
+ fs.Bool("C", true, "a boolean defaulting to true")
+ fs.String("D", "", "set relative `path` for local imports")
+ fs.String("E", "0", "issue 23543")
+ fs.Float64("F", 2.7, "a non-zero `number`")
+ fs.Float64("G", 0, "a float that defaults to zero")
+ fs.String("M", "", "a multiline\nhelp\nstring")
+ fs.Int("N", 27, "a non-zero int")
+ fs.Bool("O", true, "a flag\nmultiline help string")
+ fs.Var(&flagVar{"a", "b"}, "V", "a `list` of strings")
+ fs.Int("Z", 0, "an int that defaults to zero")
+ fs.Var(&zeroPanicker{true, ""}, "ZP0", "a flag whose String method panics when it is zero")
+ fs.Var(&zeroPanicker{true, "something"}, "ZP1", "a flag whose String method panics when it is zero")
+ fs.Duration("maxT", 0, "set `timeout` for dial")
+ fs.PrintDefaults()
+ got := buf.String()
+ if got != defaultOutput {
+ t.Errorf("got:\n%q\nwant:\n%q", got, defaultOutput)
+ }
+}
+
+// Issue 19230: validate range of Int and Uint flag values.
+func TestIntFlagOverflow(t *testing.T) {
+ if strconv.IntSize != 32 {
+ return
+ }
+ ResetForTesting(nil)
+ Int("i", 0, "")
+ Uint("u", 0, "")
+ if err := Set("i", "2147483648"); err == nil {
+ t.Error("unexpected success setting Int")
+ }
+ if err := Set("u", "4294967296"); err == nil {
+ t.Error("unexpected success setting Uint")
+ }
+}
+
+// Issue 20998: Usage should respect CommandLine.output.
+func TestUsageOutput(t *testing.T) {
+ ResetForTesting(DefaultUsage)
+ var buf strings.Builder
+ CommandLine.SetOutput(&buf)
+ defer func(old []string) { os.Args = old }(os.Args)
+ os.Args = []string{"app", "-i=1", "-unknown"}
+ Parse()
+ const want = "flag provided but not defined: -i\nUsage of app:\n"
+ if got := buf.String(); got != want {
+ t.Errorf("output = %q; want %q", got, want)
+ }
+}
+
+func TestGetters(t *testing.T) {
+ expectedName := "flag set"
+ expectedErrorHandling := ContinueOnError
+ expectedOutput := io.Writer(os.Stderr)
+ fs := NewFlagSet(expectedName, expectedErrorHandling)
+
+ if fs.Name() != expectedName {
+ t.Errorf("unexpected name: got %s, expected %s", fs.Name(), expectedName)
+ }
+ if fs.ErrorHandling() != expectedErrorHandling {
+ t.Errorf("unexpected ErrorHandling: got %d, expected %d", fs.ErrorHandling(), expectedErrorHandling)
+ }
+ if fs.Output() != expectedOutput {
+ t.Errorf("unexpected output: got %#v, expected %#v", fs.Output(), expectedOutput)
+ }
+
+ expectedName = "gopher"
+ expectedErrorHandling = ExitOnError
+ expectedOutput = os.Stdout
+ fs.Init(expectedName, expectedErrorHandling)
+ fs.SetOutput(expectedOutput)
+
+ if fs.Name() != expectedName {
+ t.Errorf("unexpected name: got %s, expected %s", fs.Name(), expectedName)
+ }
+ if fs.ErrorHandling() != expectedErrorHandling {
+ t.Errorf("unexpected ErrorHandling: got %d, expected %d", fs.ErrorHandling(), expectedErrorHandling)
+ }
+ if fs.Output() != expectedOutput {
+ t.Errorf("unexpected output: got %v, expected %v", fs.Output(), expectedOutput)
+ }
+}
+
+func TestParseError(t *testing.T) {
+ for _, typ := range []string{"bool", "int", "int64", "uint", "uint64", "float64", "duration"} {
+ fs := NewFlagSet("parse error test", ContinueOnError)
+ fs.SetOutput(io.Discard)
+ _ = fs.Bool("bool", false, "")
+ _ = fs.Int("int", 0, "")
+ _ = fs.Int64("int64", 0, "")
+ _ = fs.Uint("uint", 0, "")
+ _ = fs.Uint64("uint64", 0, "")
+ _ = fs.Float64("float64", 0, "")
+ _ = fs.Duration("duration", 0, "")
+ // Strings cannot give errors.
+ args := []string{"-" + typ + "=x"}
+ err := fs.Parse(args) // x is not a valid setting for any flag.
+ if err == nil {
+ t.Errorf("Parse(%q)=%v; expected parse error", args, err)
+ continue
+ }
+ if !strings.Contains(err.Error(), "invalid") || !strings.Contains(err.Error(), "parse error") {
+ t.Errorf("Parse(%q)=%v; expected parse error", args, err)
+ }
+ }
+}
+
+func TestRangeError(t *testing.T) {
+ bad := []string{
+ "-int=123456789012345678901",
+ "-int64=123456789012345678901",
+ "-uint=123456789012345678901",
+ "-uint64=123456789012345678901",
+ "-float64=1e1000",
+ }
+ for _, arg := range bad {
+ fs := NewFlagSet("parse error test", ContinueOnError)
+ fs.SetOutput(io.Discard)
+ _ = fs.Int("int", 0, "")
+ _ = fs.Int64("int64", 0, "")
+ _ = fs.Uint("uint", 0, "")
+ _ = fs.Uint64("uint64", 0, "")
+ _ = fs.Float64("float64", 0, "")
+ // Strings cannot give errors, and bools and durations do not return strconv.NumError.
+ err := fs.Parse([]string{arg})
+ if err == nil {
+ t.Errorf("Parse(%q)=%v; expected range error", arg, err)
+ continue
+ }
+ if !strings.Contains(err.Error(), "invalid") || !strings.Contains(err.Error(), "value out of range") {
+ t.Errorf("Parse(%q)=%v; expected range error", arg, err)
+ }
+ }
+}
+
+func TestExitCode(t *testing.T) {
+ testenv.MustHaveExec(t)
+
+ magic := 123
+ if os.Getenv("GO_CHILD_FLAG") != "" {
+ fs := NewFlagSet("test", ExitOnError)
+ if os.Getenv("GO_CHILD_FLAG_HANDLE") != "" {
+ var b bool
+ fs.BoolVar(&b, os.Getenv("GO_CHILD_FLAG_HANDLE"), false, "")
+ }
+ fs.Parse([]string{os.Getenv("GO_CHILD_FLAG")})
+ os.Exit(magic)
+ }
+
+ tests := []struct {
+ flag string
+ flagHandle string
+ expectExit int
+ }{
+ {
+ flag: "-h",
+ expectExit: 0,
+ },
+ {
+ flag: "-help",
+ expectExit: 0,
+ },
+ {
+ flag: "-undefined",
+ expectExit: 2,
+ },
+ {
+ flag: "-h",
+ flagHandle: "h",
+ expectExit: magic,
+ },
+ {
+ flag: "-help",
+ flagHandle: "help",
+ expectExit: magic,
+ },
+ }
+
+ for _, test := range tests {
+ cmd := exec.Command(testenv.Executable(t), "-test.run=^TestExitCode$")
+ cmd.Env = append(
+ os.Environ(),
+ "GO_CHILD_FLAG="+test.flag,
+ "GO_CHILD_FLAG_HANDLE="+test.flagHandle,
+ )
+ cmd.Run()
+ got := cmd.ProcessState.ExitCode()
+ // ExitCode is either 0 or 1 on Plan 9.
+ if runtime.GOOS == "plan9" && test.expectExit != 0 {
+ test.expectExit = 1
+ }
+ if got != test.expectExit {
+ t.Errorf("unexpected exit code for test case %+v \n: got %d, expect %d",
+ test, got, test.expectExit)
+ }
+ }
+}
+
+func mustPanic(t *testing.T, testName string, expected string, f func()) {
+ t.Helper()
+ defer func() {
+ switch msg := recover().(type) {
+ case nil:
+ t.Errorf("%s\n: expected panic(%q), but did not panic", testName, expected)
+ case string:
+ if ok, _ := regexp.MatchString(expected, msg); !ok {
+ t.Errorf("%s\n: expected panic(%q), but got panic(%q)", testName, expected, msg)
+ }
+ default:
+ t.Errorf("%s\n: expected panic(%q), but got panic(%T%v)", testName, expected, msg, msg)
+ }
+ }()
+ f()
+}
+
+func TestInvalidFlags(t *testing.T) {
+ tests := []struct {
+ flag string
+ errorMsg string
+ }{
+ {
+ flag: "-foo",
+ errorMsg: "flag \"-foo\" begins with -",
+ },
+ {
+ flag: "foo=bar",
+ errorMsg: "flag \"foo=bar\" contains =",
+ },
+ }
+
+ for _, test := range tests {
+ testName := fmt.Sprintf("FlagSet.Var(&v, %q, \"\")", test.flag)
+
+ fs := NewFlagSet("", ContinueOnError)
+ buf := &strings.Builder{}
+ fs.SetOutput(buf)
+
+ mustPanic(t, testName, test.errorMsg, func() {
+ var v flagVar
+ fs.Var(&v, test.flag, "")
+ })
+ if msg := test.errorMsg + "\n"; msg != buf.String() {
+ t.Errorf("%s\n: unexpected output: expected %q, bug got %q", testName, msg, buf)
+ }
+ }
+}
+
+func TestRedefinedFlags(t *testing.T) {
+ tests := []struct {
+ flagSetName string
+ errorMsg string
+ }{
+ {
+ flagSetName: "",
+ errorMsg: "flag redefined: foo",
+ },
+ {
+ flagSetName: "fs",
+ errorMsg: "fs flag redefined: foo",
+ },
+ }
+
+ for _, test := range tests {
+ testName := fmt.Sprintf("flag redefined in FlagSet(%q)", test.flagSetName)
+
+ fs := NewFlagSet(test.flagSetName, ContinueOnError)
+ buf := &strings.Builder{}
+ fs.SetOutput(buf)
+
+ var v flagVar
+ fs.Var(&v, "foo", "")
+
+ mustPanic(t, testName, test.errorMsg, func() {
+ fs.Var(&v, "foo", "")
+ })
+ if msg := test.errorMsg + "\n"; msg != buf.String() {
+ t.Errorf("%s\n: unexpected output: expected %q, bug got %q", testName, msg, buf)
+ }
+ }
+}
+
+func TestUserDefinedBoolFunc(t *testing.T) {
+ flags := NewFlagSet("test", ContinueOnError)
+ flags.SetOutput(io.Discard)
+ var ss []string
+ flags.BoolFunc("v", "usage", func(s string) error {
+ ss = append(ss, s)
+ return nil
+ })
+ if err := flags.Parse([]string{"-v", "", "-v", "1", "-v=2"}); err != nil {
+ t.Error(err)
+ }
+ if len(ss) != 1 {
+ t.Fatalf("got %d args; want 1 arg", len(ss))
+ }
+ want := "[true]"
+ if got := fmt.Sprint(ss); got != want {
+ t.Errorf("got %q; want %q", got, want)
+ }
+ // test usage
+ var buf strings.Builder
+ flags.SetOutput(&buf)
+ flags.Parse([]string{"-h"})
+ if usage := buf.String(); !strings.Contains(usage, "usage") {
+ t.Errorf("usage string not included: %q", usage)
+ }
+ // test BoolFunc error
+ flags = NewFlagSet("test", ContinueOnError)
+ flags.SetOutput(io.Discard)
+ flags.BoolFunc("v", "usage", func(s string) error {
+ return fmt.Errorf("test error")
+ })
+ // flag not set, so no error
+ if err := flags.Parse(nil); err != nil {
+ t.Error(err)
+ }
+ // flag set, expect error
+ if err := flags.Parse([]string{"-v", ""}); err == nil {
+ t.Error("got err == nil; want err != nil")
+ } else if errMsg := err.Error(); !strings.Contains(errMsg, "test error") {
+ t.Errorf(`got %q; error should contain "test error"`, errMsg)
+ }
+}
+
+func TestDefineAfterSet(t *testing.T) {
+ flags := NewFlagSet("test", ContinueOnError)
+ // Set by itself doesn't panic.
+ flags.Set("myFlag", "value")
+
+ // Define-after-set panics.
+ mustPanic(t, "DefineAfterSet", "flag myFlag set at .*/flag_test.go:.* before being defined", func() {
+ _ = flags.String("myFlag", "default", "usage")
+ })
+}
diff --git a/go/src/fmt/doc.go b/go/src/fmt/doc.go
new file mode 100644
index 0000000000000000000000000000000000000000..46f30b44e9a72289772d7078377e61db9259c896
--- /dev/null
+++ b/go/src/fmt/doc.go
@@ -0,0 +1,399 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package fmt implements formatted I/O with functions analogous
+to C's printf and scanf. The format 'verbs' are derived from C's but
+are simpler.
+
+# Printing
+
+There are four families of printing functions defined by their output destination.
+[Print], [Println] and [Printf] write to [os.Stdout];
+[Sprint], [Sprintln] and [Sprintf] return a string;
+[Fprint], [Fprintln] and [Fprintf] write to an [io.Writer]; and
+[Append], [Appendln] and [Appendf] append the output to a byte slice.
+
+The functions within each family do the formatting according to the end of the name.
+Print, Sprint, Fprint and Append use the default format for each argument,
+adding a space between operands when neither is a string.
+Println, Sprintln, Fprintln and Appendln always add spaces and append a newline.
+Printf, Sprintf, Fprintf and Appendf use a sequence of "verbs" to control the formatting.
+
+The verbs:
+
+General:
+
+ %v the value in a default format
+ when printing structs, the plus flag (%+v) adds field names
+ %#v a Go-syntax representation of the value
+ (floating-point infinities and NaNs print as ±Inf and NaN)
+ %T a Go-syntax representation of the type of the value
+ %% a literal percent sign; consumes no value
+
+Boolean:
+
+ %t the word true or false
+
+Integer:
+
+ %b base 2
+ %c the character represented by the corresponding Unicode code point
+ %d base 10
+ %o base 8
+ %O base 8 with 0o prefix
+ %q a single-quoted character literal safely escaped with Go syntax.
+ %x base 16, with lower-case letters for a-f
+ %X base 16, with upper-case letters for A-F
+ %U Unicode format: U+1234; same as "U+%04X"
+
+Floating-point and complex constituents:
+
+ %b decimalless scientific notation with exponent a power of two,
+ in the manner of strconv.FormatFloat with the 'b' format,
+ e.g. -123456p-78
+ %e scientific notation, e.g. -1.234456e+78
+ %E scientific notation, e.g. -1.234456E+78
+ %f decimal point but no exponent, e.g. 123.456
+ %F synonym for %f
+ %g %e for large exponents, %f otherwise. Precision is discussed below.
+ %G %E for large exponents, %F otherwise
+ %x hexadecimal notation (with decimal power of two exponent), e.g. -0x1.23abcp+20
+ %X upper-case hexadecimal notation, e.g. -0X1.23ABCP+20
+
+ The exponent is always a decimal integer.
+ For formats other than %b the exponent is at least two digits.
+
+String and slice of bytes (treated equivalently with these verbs):
+
+ %s the uninterpreted bytes of the string or slice
+ %q a double-quoted string safely escaped with Go syntax
+ %x base 16, lower-case, two characters per byte
+ %X base 16, upper-case, two characters per byte
+
+Slice:
+
+ %p address of 0th element in base 16 notation, with leading 0x
+
+Pointer:
+
+ %p base 16 notation, with leading 0x
+ The %b, %d, %o, %x and %X verbs also work with pointers,
+ formatting the value exactly as if it were an integer.
+
+The default format for %v is:
+
+ bool: %t
+ int, int8 etc.: %d
+ uint, uint8 etc.: %d, %#x if printed with %#v
+ float32, complex64, etc: %g
+ string: %s
+ chan: %p
+ pointer: %p
+
+For compound objects, the elements are printed using these rules, recursively,
+laid out like this:
+
+ struct: {field0 field1 ...}
+ array, slice: [elem0 elem1 ...]
+ maps: map[key1:value1 key2:value2 ...]
+ pointer to above: &{}, &[], &map[]
+
+Width is specified by an optional decimal number immediately preceding the verb.
+If absent, the width is whatever is necessary to represent the value.
+Precision is specified after the (optional) width by a period followed by a
+decimal number. If no period is present, a default precision is used.
+A period with no following number specifies a precision of zero.
+Examples:
+
+ %f default width, default precision
+ %9f width 9, default precision
+ %.2f default width, precision 2
+ %9.2f width 9, precision 2
+ %9.f width 9, precision 0
+
+Width and precision are measured in units of Unicode code points,
+that is, runes. (This differs from C's printf where the
+units are always measured in bytes.) Either or both of the flags
+may be replaced with the character '*', causing their values to be
+obtained from the next operand (preceding the one to format),
+which must be of type int.
+
+For most values, width is the minimum number of runes to output,
+padding the formatted form with spaces if necessary.
+
+For strings, byte slices and byte arrays, however, precision
+limits the length of the input to be formatted (not the size of
+the output), truncating if necessary. Normally it is measured in
+runes, but for these types when formatted with the %x or %X format
+it is measured in bytes.
+
+For floating-point values, width sets the minimum width of the field and
+precision sets the number of places after the decimal, if appropriate,
+except that for %g/%G precision sets the maximum number of significant
+digits (trailing zeros are removed). For example, given 12.345 the format
+%6.3f prints 12.345 while %.3g prints 12.3. The default precision for %e, %f
+and %#g is 6; for %g it is the smallest number of digits necessary to identify
+the value uniquely.
+
+For complex numbers, the width and precision apply to the two
+components independently and the result is parenthesized, so %f applied
+to 1.2+3.4i produces (1.200000+3.400000i).
+
+When formatting a single integer code point or a rune string (type []rune)
+with %q, invalid Unicode code points are changed to the Unicode replacement
+character, U+FFFD, as in [strconv.QuoteRune].
+
+Other flags:
+
+ '+' always print a sign for numeric values;
+ guarantee ASCII-only output for %q (%+q)
+ '-' pad with spaces on the right rather than the left (left-justify the field)
+ '#' alternate format: add leading 0b for binary (%#b), 0 for octal (%#o),
+ 0x or 0X for hex (%#x or %#X); suppress 0x for %p (%#p);
+ for %q, print a raw (backquoted) string if [strconv.CanBackquote]
+ returns true;
+ always print a decimal point for %e, %E, %f, %F, %g and %G;
+ do not remove trailing zeros for %g and %G;
+ write e.g. U+0078 'x' if the character is printable for %U (%#U)
+ ' ' (space) leave a space for elided sign in numbers (% d);
+ put spaces between bytes printing strings or slices in hex (% x, % X)
+ '0' pad with leading zeros rather than spaces;
+ for numbers, this moves the padding after the sign
+
+Flags are ignored by verbs that do not expect them.
+For example there is no alternate decimal format, so %#d and %d
+behave identically.
+
+For each Printf-like function, there is also a Print function
+that takes no format and is equivalent to saying %v for every
+operand. Another variant Println inserts blanks between
+operands and appends a newline.
+
+Regardless of the verb, if an operand is an interface value,
+the internal concrete value is used, not the interface itself.
+Thus:
+
+ var i interface{} = 23
+ fmt.Printf("%v\n", i)
+
+will print 23.
+
+Except when printed using the verbs %T and %p, special
+formatting considerations apply for operands that implement
+certain interfaces. In order of application:
+
+1. If the operand is a [reflect.Value], the operand is replaced by the
+concrete value that it holds, and printing continues with the next rule.
+
+2. If an operand implements the [Formatter] interface, it will
+be invoked. In this case the interpretation of verbs and flags is
+controlled by that implementation.
+
+3. If the %v verb is used with the # flag (%#v) and the operand
+implements the [GoStringer] interface, that will be invoked.
+
+If the format (which is implicitly %v for [Println] etc.) is valid
+for a string (%s %q %x %X), or is %v but not %#v,
+the following two rules apply:
+
+4. If an operand implements the error interface, the Error method
+will be invoked to convert the object to a string, which will then
+be formatted as required by the verb (if any).
+
+5. If an operand implements method String() string, that method
+will be invoked to convert the object to a string, which will then
+be formatted as required by the verb (if any).
+
+For compound operands such as slices and structs, the format
+applies to the elements of each operand, recursively, not to the
+operand as a whole. Thus %q will quote each element of a slice
+of strings, and %6.2f will control formatting for each element
+of a floating-point array.
+
+However, when printing a byte slice with a string-like verb
+(%s %q %x %X), it is treated identically to a string, as a single item.
+
+To avoid recursion in cases such as
+
+ type X string
+ func (x X) String() string { return Sprintf("<%s>", x) }
+
+convert the value before recurring:
+
+ func (x X) String() string { return Sprintf("<%s>", string(x)) }
+
+Infinite recursion can also be triggered by self-referential data
+structures, such as a slice that contains itself as an element, if
+that type has a String method. Such pathologies are rare, however,
+and the package does not protect against them.
+
+When printing a struct, fmt cannot and therefore does not invoke
+formatting methods such as Error or String on unexported fields.
+
+# Explicit argument indexes
+
+In [Printf], [Sprintf], [Fprintf], and [Appendf], the default behavior is for each
+formatting verb to format successive arguments passed in the call.
+However, the notation [n] immediately before the verb indicates that the
+nth one-indexed argument is to be formatted instead. The same notation
+before a '*' for a width or precision selects the argument index holding
+the value. After processing a bracketed expression [n], subsequent verbs
+will use arguments n+1, n+2, etc. unless otherwise directed.
+
+For example,
+
+ fmt.Sprintf("%[2]d %[1]d\n", 11, 22)
+
+will yield "22 11", while
+
+ fmt.Sprintf("%[3]*.[2]*[1]f", 12.0, 2, 6)
+
+equivalent to
+
+ fmt.Sprintf("%6.2f", 12.0)
+
+will yield " 12.00". Because an explicit index affects subsequent verbs,
+this notation can be used to print the same values multiple times
+by resetting the index for the first argument to be repeated:
+
+ fmt.Sprintf("%d %d %#[1]x %#x", 16, 17)
+
+will yield "16 17 0x10 0x11".
+
+# Format errors
+
+If an invalid argument is given for a verb, such as providing
+a string to %d, the generated string will contain a
+description of the problem, as in these examples:
+
+ Wrong type or unknown verb: %!verb(type=value)
+ Printf("%d", "hi"): %!d(string=hi)
+ Too many arguments: %!(EXTRA type=value)
+ Printf("hi", "guys"): hi%!(EXTRA string=guys)
+ Too few arguments: %!verb(MISSING)
+ Printf("hi%d"): hi%!d(MISSING)
+ Non-int for width or precision: %!(BADWIDTH) or %!(BADPREC)
+ Printf("%*s", 4.5, "hi"): %!(BADWIDTH)hi
+ Printf("%.*s", 4.5, "hi"): %!(BADPREC)hi
+ Invalid or invalid use of argument index: %!(BADINDEX)
+ Printf("%*[2]d", 7): %!d(BADINDEX)
+ Printf("%.[2]d", 7): %!d(BADINDEX)
+
+All errors begin with the string "%!" followed sometimes
+by a single character (the verb) and end with a parenthesized
+description.
+
+If an Error or String method triggers a panic when called by a
+print routine, the fmt package reformats the error message
+from the panic, decorating it with an indication that it came
+through the fmt package. For example, if a String method
+calls panic("bad"), the resulting formatted message will look
+like
+
+ %!s(PANIC=bad)
+
+The %!s just shows the print verb in use when the failure
+occurred. If the panic is caused by a nil receiver to an Error,
+String, or GoString method, however, the output is the undecorated
+string, "".
+
+# Scanning
+
+An analogous set of functions scans formatted text to yield
+values. [Scan], [Scanf] and [Scanln] read from [os.Stdin]; [Fscan],
+[Fscanf] and [Fscanln] read from a specified [io.Reader]; [Sscan],
+[Sscanf] and [Sscanln] read from an argument string.
+
+[Scan], [Fscan], [Sscan] treat newlines in the input as spaces.
+
+[Scanln], [Fscanln] and [Sscanln] stop scanning at a newline and
+require that the items be followed by a newline or EOF.
+
+[Scanf], [Fscanf], and [Sscanf] parse the arguments according to a
+format string, analogous to that of [Printf]. In the text that
+follows, 'space' means any Unicode whitespace character
+except newline.
+
+In the format string, a verb introduced by the % character
+consumes and parses input; these verbs are described in more
+detail below. A character other than %, space, or newline in
+the format consumes exactly that input character, which must
+be present. A newline with zero or more spaces before it in
+the format string consumes zero or more spaces in the input
+followed by a single newline or the end of the input. A space
+following a newline in the format string consumes zero or more
+spaces in the input. Otherwise, any run of one or more spaces
+in the format string consumes as many spaces as possible in
+the input. Unless the run of spaces in the format string
+appears adjacent to a newline, the run must consume at least
+one space from the input or find the end of the input.
+
+The handling of spaces and newlines differs from that of C's
+scanf family: in C, newlines are treated as any other space,
+and it is never an error when a run of spaces in the format
+string finds no spaces to consume in the input.
+
+The verbs behave analogously to those of [Printf].
+For example, %x will scan an integer as a hexadecimal number,
+and %v will scan the default representation format for the value.
+The [Printf] verbs %p and %T and the flags # and + are not implemented.
+For floating-point and complex values, all valid formatting verbs
+(%b %e %E %f %F %g %G %x %X and %v) are equivalent and accept
+both decimal and hexadecimal notation (for example: "2.3e+7", "0x4.5p-8")
+and digit-separating underscores (for example: "3.14159_26535_89793").
+
+Input processed by verbs is implicitly space-delimited: the
+implementation of every verb except %c starts by discarding
+leading spaces from the remaining input, and the %s verb
+(and %v reading into a string) stops consuming input at the first
+space or newline character.
+
+The familiar base-setting prefixes 0b (binary), 0o and 0 (octal),
+and 0x (hexadecimal) are accepted when scanning integers
+without a format or with the %v verb, as are digit-separating
+underscores.
+
+Width is interpreted in the input text but there is no
+syntax for scanning with a precision (no %5.2f, just %5f).
+If width is provided, it applies after leading spaces are
+trimmed and specifies the maximum number of runes to read
+to satisfy the verb. For example,
+
+ Sscanf(" 1234567 ", "%5s%d", &s, &i)
+
+will set s to "12345" and i to 67 while
+
+ Sscanf(" 12 34 567 ", "%5s%d", &s, &i)
+
+will set s to "12" and i to 34.
+
+In all the scanning functions, a carriage return followed
+immediately by a newline is treated as a plain newline
+(\r\n means the same as \n).
+
+In all the scanning functions, if an operand implements method
+[Scan] (that is, it implements the [Scanner] interface) that
+method will be used to scan the text for that operand. Also,
+if the number of arguments scanned is less than the number of
+arguments provided, an error is returned.
+
+All arguments to be scanned must be either pointers to basic
+types or implementations of the [Scanner] interface.
+
+Like [Scanf] and [Fscanf], [Sscanf] need not consume its entire input.
+There is no way to recover how much of the input string [Sscanf] used.
+
+Note: [Fscan] etc. can read one character (rune) past the input
+they return, which means that a loop calling a scan routine
+may skip some of the input. This is usually a problem only
+when there is no space between input values. If the reader
+provided to [Fscan] implements ReadRune, that method will be used
+to read characters. If the reader also implements UnreadRune,
+that method will be used to save the character and successive
+calls will not lose data. To attach ReadRune and UnreadRune
+methods to a reader without that capability, use
+[bufio.NewReader].
+*/
+package fmt
diff --git a/go/src/fmt/errors.go b/go/src/fmt/errors.go
new file mode 100644
index 0000000000000000000000000000000000000000..a0ce7ada346dbc0dbb122e1c5006c1ab89bb1e69
--- /dev/null
+++ b/go/src/fmt/errors.go
@@ -0,0 +1,94 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package fmt
+
+import (
+ "errors"
+ "internal/stringslite"
+ "slices"
+)
+
+// Errorf formats according to a format specifier and returns the string as a
+// value that satisfies error.
+//
+// If the format specifier includes a %w verb with an error operand,
+// the returned error will implement an Unwrap method returning the operand.
+// If there is more than one %w verb, the returned error will implement an
+// Unwrap method returning a []error containing all the %w operands in the
+// order they appear in the arguments.
+// It is invalid to supply the %w verb with an operand that does not implement
+// the error interface. The %w verb is otherwise a synonym for %v.
+func Errorf(format string, a ...any) (err error) {
+ // This function has been split in a somewhat unnatural way
+ // so that both it and the errors.New call can be inlined.
+ if err = errorf(format, a...); err != nil {
+ return err
+ }
+ // No formatting was needed. We can avoid some allocations and other work.
+ // See https://go.dev/cl/708836 for details.
+ return errors.New(format)
+}
+
+// errorf formats and returns an error value, or nil if no formatting is required.
+func errorf(format string, a ...any) error {
+ if len(a) == 0 && stringslite.IndexByte(format, '%') == -1 {
+ return nil
+ }
+ p := newPrinter()
+ p.wrapErrs = true
+ p.doPrintf(format, a)
+ s := string(p.buf)
+ var err error
+ switch len(p.wrappedErrs) {
+ case 0:
+ err = errors.New(s)
+ case 1:
+ w := &wrapError{msg: s}
+ w.err, _ = a[p.wrappedErrs[0]].(error)
+ err = w
+ default:
+ if p.reordered {
+ slices.Sort(p.wrappedErrs)
+ }
+ var errs []error
+ for i, argNum := range p.wrappedErrs {
+ if i > 0 && p.wrappedErrs[i-1] == argNum {
+ continue
+ }
+ if e, ok := a[argNum].(error); ok {
+ errs = append(errs, e)
+ }
+ }
+ err = &wrapErrors{s, errs}
+ }
+ p.free()
+ return err
+}
+
+type wrapError struct {
+ msg string
+ err error
+}
+
+func (e *wrapError) Error() string {
+ return e.msg
+}
+
+func (e *wrapError) Unwrap() error {
+ return e.err
+}
+
+type wrapErrors struct {
+ msg string
+ errs []error
+}
+
+func (e *wrapErrors) Error() string {
+ return e.msg
+}
+
+func (e *wrapErrors) Unwrap() []error {
+ return e.errs
+}
diff --git a/go/src/fmt/errors_test.go b/go/src/fmt/errors_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..52bf42d0a623a682dd03fd5016f2af90a48001ba
--- /dev/null
+++ b/go/src/fmt/errors_test.go
@@ -0,0 +1,116 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package fmt_test
+
+import (
+ "errors"
+ "fmt"
+ "reflect"
+ "testing"
+)
+
+func TestErrorf(t *testing.T) {
+ // noVetErrorf is an alias for fmt.Errorf that does not trigger vet warnings for
+ // %w format strings.
+ noVetErrorf := fmt.Errorf
+
+ wrapped := errors.New("inner error")
+ for _, test := range []struct {
+ err error
+ wantText string
+ wantUnwrap error
+ wantSplit []error
+ }{{
+ err: fmt.Errorf("%w", wrapped),
+ wantText: "inner error",
+ wantUnwrap: wrapped,
+ }, {
+ err: fmt.Errorf("added context: %w", wrapped),
+ wantText: "added context: inner error",
+ wantUnwrap: wrapped,
+ }, {
+ err: fmt.Errorf("%w with added context", wrapped),
+ wantText: "inner error with added context",
+ wantUnwrap: wrapped,
+ }, {
+ err: fmt.Errorf("%s %w %v", "prefix", wrapped, "suffix"),
+ wantText: "prefix inner error suffix",
+ wantUnwrap: wrapped,
+ }, {
+ err: fmt.Errorf("%[2]s: %[1]w", wrapped, "positional verb"),
+ wantText: "positional verb: inner error",
+ wantUnwrap: wrapped,
+ }, {
+ err: fmt.Errorf("%v", wrapped),
+ wantText: "inner error",
+ }, {
+ err: fmt.Errorf("added context: %v", wrapped),
+ wantText: "added context: inner error",
+ }, {
+ err: fmt.Errorf("%v with added context", wrapped),
+ wantText: "inner error with added context",
+ }, {
+ err: noVetErrorf("%w is not an error", "not-an-error"),
+ wantText: "%!w(string=not-an-error) is not an error",
+ }, {
+ err: fmt.Errorf("no verbs"),
+ wantText: "no verbs",
+ }, {
+ err: noVetErrorf("no verbs with extra arg", "extra"),
+ wantText: "no verbs with extra arg%!(EXTRA string=extra)",
+ }, {
+ err: noVetErrorf("too many verbs: %w %v"),
+ wantText: "too many verbs: %!w(MISSING) %!v(MISSING)",
+ }, {
+ err: noVetErrorf("wrapped two errors: %w %w", errString("1"), errString("2")),
+ wantText: "wrapped two errors: 1 2",
+ wantSplit: []error{errString("1"), errString("2")},
+ }, {
+ err: noVetErrorf("wrapped three errors: %w %w %w", errString("1"), errString("2"), errString("3")),
+ wantText: "wrapped three errors: 1 2 3",
+ wantSplit: []error{errString("1"), errString("2"), errString("3")},
+ }, {
+ err: noVetErrorf("wrapped nil error: %w %w %w", errString("1"), nil, errString("2")),
+ wantText: "wrapped nil error: 1 %!w() 2",
+ wantSplit: []error{errString("1"), errString("2")},
+ }, {
+ err: noVetErrorf("wrapped one non-error: %w %w %w", errString("1"), "not-an-error", errString("3")),
+ wantText: "wrapped one non-error: 1 %!w(string=not-an-error) 3",
+ wantSplit: []error{errString("1"), errString("3")},
+ }, {
+ err: fmt.Errorf("wrapped errors out of order: %[3]w %[2]w %[1]w", errString("1"), errString("2"), errString("3")),
+ wantText: "wrapped errors out of order: 3 2 1",
+ wantSplit: []error{errString("1"), errString("2"), errString("3")},
+ }, {
+ err: fmt.Errorf("wrapped several times: %[1]w %[1]w %[2]w %[1]w", errString("1"), errString("2")),
+ wantText: "wrapped several times: 1 1 2 1",
+ wantSplit: []error{errString("1"), errString("2")},
+ }, {
+ err: fmt.Errorf("%w", nil),
+ wantText: "%!w()",
+ wantUnwrap: nil, // still nil
+ }} {
+ if got, want := errors.Unwrap(test.err), test.wantUnwrap; got != want {
+ t.Errorf("Formatted error: %v\nerrors.Unwrap() = %v, want %v", test.err, got, want)
+ }
+ if got, want := splitErr(test.err), test.wantSplit; !reflect.DeepEqual(got, want) {
+ t.Errorf("Formatted error: %v\nUnwrap() []error = %v, want %v", test.err, got, want)
+ }
+ if got, want := test.err.Error(), test.wantText; got != want {
+ t.Errorf("err.Error() = %q, want %q", got, want)
+ }
+ }
+}
+
+func splitErr(err error) []error {
+ if e, ok := err.(interface{ Unwrap() []error }); ok {
+ return e.Unwrap()
+ }
+ return nil
+}
+
+type errString string
+
+func (e errString) Error() string { return string(e) }
diff --git a/go/src/fmt/example_test.go b/go/src/fmt/example_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..5962834226b9d58564eafa1b240a9ff4e99171fc
--- /dev/null
+++ b/go/src/fmt/example_test.go
@@ -0,0 +1,365 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package fmt_test
+
+import (
+ "fmt"
+ "io"
+ "math"
+ "os"
+ "strings"
+ "time"
+)
+
+// The Errorf function lets us use formatting features
+// to create descriptive error messages.
+func ExampleErrorf() {
+ const name, id = "bueller", 17
+ err := fmt.Errorf("user %q (id %d) not found", name, id)
+ fmt.Println(err.Error())
+
+ // Output: user "bueller" (id 17) not found
+}
+
+func ExampleFscanf() {
+ var (
+ i int
+ b bool
+ s string
+ )
+ r := strings.NewReader("5 true gophers")
+ n, err := fmt.Fscanf(r, "%d %t %s", &i, &b, &s)
+ if err != nil {
+ fmt.Fprintf(os.Stderr, "Fscanf: %v\n", err)
+ }
+ fmt.Println(i, b, s)
+ fmt.Println(n)
+ // Output:
+ // 5 true gophers
+ // 3
+}
+
+func ExampleFscanln() {
+ s := `dmr 1771 1.61803398875
+ ken 271828 3.14159`
+ r := strings.NewReader(s)
+ var a string
+ var b int
+ var c float64
+ for {
+ n, err := fmt.Fscanln(r, &a, &b, &c)
+ if err == io.EOF {
+ break
+ }
+ if err != nil {
+ panic(err)
+ }
+ fmt.Printf("%d: %s, %d, %f\n", n, a, b, c)
+ }
+ // Output:
+ // 3: dmr, 1771, 1.618034
+ // 3: ken, 271828, 3.141590
+}
+
+func ExampleSscanf() {
+ var name string
+ var age int
+ n, err := fmt.Sscanf("Kim is 22 years old", "%s is %d years old", &name, &age)
+ if err != nil {
+ panic(err)
+ }
+ fmt.Printf("%d: %s, %d\n", n, name, age)
+
+ // Output:
+ // 2: Kim, 22
+}
+
+func ExamplePrint() {
+ const name, age = "Kim", 22
+ fmt.Print(name, " is ", age, " years old.\n")
+
+ // It is conventional not to worry about any
+ // error returned by Print.
+
+ // Output:
+ // Kim is 22 years old.
+}
+
+func ExamplePrintln() {
+ const name, age = "Kim", 22
+ fmt.Println(name, "is", age, "years old.")
+
+ // It is conventional not to worry about any
+ // error returned by Println.
+
+ // Output:
+ // Kim is 22 years old.
+}
+
+func ExamplePrintf() {
+ const name, age = "Kim", 22
+ fmt.Printf("%s is %d years old.\n", name, age)
+
+ // It is conventional not to worry about any
+ // error returned by Printf.
+
+ // Output:
+ // Kim is 22 years old.
+}
+
+func ExampleSprint() {
+ const name, age = "Kim", 22
+ s := fmt.Sprint(name, " is ", age, " years old.\n")
+
+ io.WriteString(os.Stdout, s) // Ignoring error for simplicity.
+
+ // Output:
+ // Kim is 22 years old.
+}
+
+func ExampleSprintln() {
+ const name, age = "Kim", 22
+ s := fmt.Sprintln(name, "is", age, "years old.")
+
+ io.WriteString(os.Stdout, s) // Ignoring error for simplicity.
+
+ // Output:
+ // Kim is 22 years old.
+}
+
+func ExampleSprintf() {
+ const name, age = "Kim", 22
+ s := fmt.Sprintf("%s is %d years old.\n", name, age)
+
+ io.WriteString(os.Stdout, s) // Ignoring error for simplicity.
+
+ // Output:
+ // Kim is 22 years old.
+}
+
+func ExampleFprint() {
+ const name, age = "Kim", 22
+ n, err := fmt.Fprint(os.Stdout, name, " is ", age, " years old.\n")
+
+ // The n and err return values from Fprint are
+ // those returned by the underlying io.Writer.
+ if err != nil {
+ fmt.Fprintf(os.Stderr, "Fprint: %v\n", err)
+ }
+ fmt.Print(n, " bytes written.\n")
+
+ // Output:
+ // Kim is 22 years old.
+ // 21 bytes written.
+}
+
+func ExampleFprintln() {
+ const name, age = "Kim", 22
+ n, err := fmt.Fprintln(os.Stdout, name, "is", age, "years old.")
+
+ // The n and err return values from Fprintln are
+ // those returned by the underlying io.Writer.
+ if err != nil {
+ fmt.Fprintf(os.Stderr, "Fprintln: %v\n", err)
+ }
+ fmt.Println(n, "bytes written.")
+
+ // Output:
+ // Kim is 22 years old.
+ // 21 bytes written.
+}
+
+func ExampleFprintf() {
+ const name, age = "Kim", 22
+ n, err := fmt.Fprintf(os.Stdout, "%s is %d years old.\n", name, age)
+
+ // The n and err return values from Fprintf are
+ // those returned by the underlying io.Writer.
+ if err != nil {
+ fmt.Fprintf(os.Stderr, "Fprintf: %v\n", err)
+ }
+ fmt.Printf("%d bytes written.\n", n)
+
+ // Output:
+ // Kim is 22 years old.
+ // 21 bytes written.
+}
+
+// Print, Println, and Printf lay out their arguments differently. In this example
+// we can compare their behaviors. Println always adds blanks between the items it
+// prints, while Print adds blanks only between non-string arguments and Printf
+// does exactly what it is told.
+// Sprint, Sprintln, Sprintf, Fprint, Fprintln, and Fprintf behave the same as
+// their corresponding Print, Println, and Printf functions shown here.
+func Example_printers() {
+ a, b := 3.0, 4.0
+ h := math.Hypot(a, b)
+
+ // Print inserts blanks between arguments when neither is a string.
+ // It does not add a newline to the output, so we add one explicitly.
+ fmt.Print("The vector (", a, b, ") has length ", h, ".\n")
+
+ // Println always inserts spaces between its arguments,
+ // so it cannot be used to produce the same output as Print in this case;
+ // its output has extra spaces.
+ // Also, Println always adds a newline to the output.
+ fmt.Println("The vector (", a, b, ") has length", h, ".")
+
+ // Printf provides complete control but is more complex to use.
+ // It does not add a newline to the output, so we add one explicitly
+ // at the end of the format specifier string.
+ fmt.Printf("The vector (%g %g) has length %g.\n", a, b, h)
+
+ // Output:
+ // The vector (3 4) has length 5.
+ // The vector ( 3 4 ) has length 5 .
+ // The vector (3 4) has length 5.
+}
+
+// These examples demonstrate the basics of printing using a format string. Printf,
+// Sprintf, and Fprintf all take a format string that specifies how to format the
+// subsequent arguments. For example, %d (we call that a 'verb') says to print the
+// corresponding argument, which must be an integer (or something containing an
+// integer, such as a slice of ints) in decimal. The verb %v ('v' for 'value')
+// always formats the argument in its default form, just how Print or Println would
+// show it. The special verb %T ('T' for 'Type') prints the type of the argument
+// rather than its value. The examples are not exhaustive; see the package comment
+// for all the details.
+func Example_formats() {
+ // A basic set of examples showing that %v is the default format, in this
+ // case decimal for integers, which can be explicitly requested with %d;
+ // the output is just what Println generates.
+ integer := 23
+ // Each of these prints "23" (without the quotes).
+ fmt.Println(integer)
+ fmt.Printf("%v\n", integer)
+ fmt.Printf("%d\n", integer)
+
+ // The special verb %T shows the type of an item rather than its value.
+ fmt.Printf("%T %T\n", integer, &integer)
+ // Result: int *int
+
+ // Println(x) is the same as Printf("%v\n", x) so we will use only Printf
+ // in the following examples. Each one demonstrates how to format values of
+ // a particular type, such as integers or strings. We start each format
+ // string with %v to show the default output and follow that with one or
+ // more custom formats.
+
+ // Booleans print as "true" or "false" with %v or %t.
+ truth := true
+ fmt.Printf("%v %t\n", truth, truth)
+ // Result: true true
+
+ // Integers print as decimals with %v and %d,
+ // or in hex with %x, octal with %o, or binary with %b.
+ answer := 42
+ fmt.Printf("%v %d %x %o %b\n", answer, answer, answer, answer, answer)
+ // Result: 42 42 2a 52 101010
+
+ // Floats have multiple formats: %v and %g print a compact representation,
+ // while %f prints a decimal point and %e uses exponential notation. The
+ // format %6.2f used here shows how to set the width and precision to
+ // control the appearance of a floating-point value. In this instance, 6 is
+ // the total width of the printed text for the value (note the extra spaces
+ // in the output) and 2 is the number of decimal places to show.
+ pi := math.Pi
+ fmt.Printf("%v %g %.2f (%6.2f) %e\n", pi, pi, pi, pi, pi)
+ // Result: 3.141592653589793 3.141592653589793 3.14 ( 3.14) 3.141593e+00
+
+ // Complex numbers format as parenthesized pairs of floats, with an 'i'
+ // after the imaginary part.
+ point := 110.7 + 22.5i
+ fmt.Printf("%v %g %.2f %.2e\n", point, point, point, point)
+ // Result: (110.7+22.5i) (110.7+22.5i) (110.70+22.50i) (1.11e+02+2.25e+01i)
+
+ // Runes are integers but when printed with %c show the character with that
+ // Unicode value. The %q verb shows them as quoted characters, %U as a
+ // hex Unicode code point, and %#U as both a code point and a quoted
+ // printable form if the rune is printable.
+ smile := '😀'
+ fmt.Printf("%v %d %c %q %U %#U\n", smile, smile, smile, smile, smile, smile)
+ // Result: 128512 128512 😀 '😀' U+1F600 U+1F600 '😀'
+
+ // Strings are formatted with %v and %s as-is, with %q as quoted strings,
+ // and %#q as backquoted strings.
+ placeholders := `foo "bar"`
+ fmt.Printf("%v %s %q %#q\n", placeholders, placeholders, placeholders, placeholders)
+ // Result: foo "bar" foo "bar" "foo \"bar\"" `foo "bar"`
+
+ // Maps formatted with %v show keys and values in their default formats.
+ // The %#v form (the # is called a "flag" in this context) shows the map in
+ // the Go source format. Maps are printed in a consistent order, sorted
+ // by the values of the keys.
+ isLegume := map[string]bool{
+ "peanut": true,
+ "dachshund": false,
+ }
+ fmt.Printf("%v %#v\n", isLegume, isLegume)
+ // Result: map[dachshund:false peanut:true] map[string]bool{"dachshund":false, "peanut":true}
+
+ // Structs formatted with %v show field values in their default formats.
+ // The %+v form shows the fields by name, while %#v formats the struct in
+ // Go source format.
+ person := struct {
+ Name string
+ Age int
+ }{"Kim", 22}
+ fmt.Printf("%v %+v %#v\n", person, person, person)
+ // Result: {Kim 22} {Name:Kim Age:22} struct { Name string; Age int }{Name:"Kim", Age:22}
+
+ // The default format for a pointer shows the underlying value preceded by
+ // an ampersand. The %p verb prints the pointer value in hex. We use a
+ // typed nil for the argument to %p here because the value of any non-nil
+ // pointer would change from run to run; run the commented-out Printf
+ // call yourself to see.
+ pointer := &person
+ fmt.Printf("%v %p\n", pointer, (*int)(nil))
+ // Result: &{Kim 22} 0x0
+ // fmt.Printf("%v %p\n", pointer, pointer)
+ // Result: &{Kim 22} 0x010203 // See comment above.
+
+ // Arrays and slices are formatted by applying the format to each element.
+ greats := [5]string{"Kitano", "Kobayashi", "Kurosawa", "Miyazaki", "Ozu"}
+ fmt.Printf("%v %q\n", greats, greats)
+ // Result: [Kitano Kobayashi Kurosawa Miyazaki Ozu] ["Kitano" "Kobayashi" "Kurosawa" "Miyazaki" "Ozu"]
+
+ kGreats := greats[:3]
+ fmt.Printf("%v %q %#v\n", kGreats, kGreats, kGreats)
+ // Result: [Kitano Kobayashi Kurosawa] ["Kitano" "Kobayashi" "Kurosawa"] []string{"Kitano", "Kobayashi", "Kurosawa"}
+
+ // Byte slices are special. Integer verbs like %d print the elements in
+ // that format. The %s and %q forms treat the slice like a string. The %x
+ // verb has a special form with the space flag that puts a space between
+ // the bytes.
+ cmd := []byte("a⌘")
+ fmt.Printf("%v %d %s %q %x % x\n", cmd, cmd, cmd, cmd, cmd, cmd)
+ // Result: [97 226 140 152] [97 226 140 152] a⌘ "a⌘" 61e28c98 61 e2 8c 98
+
+ // Types that implement Stringer are printed the same as strings. Because
+ // Stringers return a string, we can print them using a string-specific
+ // verb such as %q.
+ now := time.Unix(123456789, 0).UTC() // time.Time implements fmt.Stringer.
+ fmt.Printf("%v %q\n", now, now)
+ // Result: 1973-11-29 21:33:09 +0000 UTC "1973-11-29 21:33:09 +0000 UTC"
+
+ // Output:
+ // 23
+ // 23
+ // 23
+ // int *int
+ // true true
+ // 42 42 2a 52 101010
+ // 3.141592653589793 3.141592653589793 3.14 ( 3.14) 3.141593e+00
+ // (110.7+22.5i) (110.7+22.5i) (110.70+22.50i) (1.11e+02+2.25e+01i)
+ // 128512 128512 😀 '😀' U+1F600 U+1F600 '😀'
+ // foo "bar" foo "bar" "foo \"bar\"" `foo "bar"`
+ // map[dachshund:false peanut:true] map[string]bool{"dachshund":false, "peanut":true}
+ // {Kim 22} {Name:Kim Age:22} struct { Name string; Age int }{Name:"Kim", Age:22}
+ // &{Kim 22} 0x0
+ // [Kitano Kobayashi Kurosawa Miyazaki Ozu] ["Kitano" "Kobayashi" "Kurosawa" "Miyazaki" "Ozu"]
+ // [Kitano Kobayashi Kurosawa] ["Kitano" "Kobayashi" "Kurosawa"] []string{"Kitano", "Kobayashi", "Kurosawa"}
+ // [97 226 140 152] [97 226 140 152] a⌘ "a⌘" 61e28c98 61 e2 8c 98
+ // 1973-11-29 21:33:09 +0000 UTC "1973-11-29 21:33:09 +0000 UTC"
+}
diff --git a/go/src/fmt/export_test.go b/go/src/fmt/export_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..14163a29afeb4e1615643220e8d554e1479c3064
--- /dev/null
+++ b/go/src/fmt/export_test.go
@@ -0,0 +1,8 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package fmt
+
+var IsSpace = isSpace
+var Parsenum = parsenum
diff --git a/go/src/fmt/fmt_test.go b/go/src/fmt/fmt_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..c07da5683c24635d02f26ec31d61aca02b438efd
--- /dev/null
+++ b/go/src/fmt/fmt_test.go
@@ -0,0 +1,2028 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package fmt_test
+
+import (
+ "bytes"
+ . "fmt"
+ "internal/race"
+ "io"
+ "math"
+ "reflect"
+ "strings"
+ "testing"
+ "time"
+ "unicode"
+)
+
+type (
+ renamedBool bool
+ renamedInt int
+ renamedInt8 int8
+ renamedInt16 int16
+ renamedInt32 int32
+ renamedInt64 int64
+ renamedUint uint
+ renamedUint8 uint8
+ renamedUint16 uint16
+ renamedUint32 uint32
+ renamedUint64 uint64
+ renamedUintptr uintptr
+ renamedString string
+ renamedBytes []byte
+ renamedFloat32 float32
+ renamedFloat64 float64
+ renamedComplex64 complex64
+ renamedComplex128 complex128
+)
+
+func TestFmtInterface(t *testing.T) {
+ var i1 any
+ i1 = "abc"
+ s := Sprintf("%s", i1)
+ if s != "abc" {
+ t.Errorf(`Sprintf("%%s", empty("abc")) = %q want %q`, s, "abc")
+ }
+}
+
+var (
+ NaN = math.NaN()
+ posInf = math.Inf(1)
+ negInf = math.Inf(-1)
+
+ intVar = 0
+
+ array = [5]int{1, 2, 3, 4, 5}
+ iarray = [4]any{1, "hello", 2.5, nil}
+ slice = array[:]
+ islice = iarray[:]
+)
+
+type A struct {
+ i int
+ j uint
+ s string
+ x []int
+}
+
+type I int
+
+func (i I) String() string { return Sprintf("<%d>", int(i)) }
+
+type B struct {
+ I I
+ j int
+}
+
+type C struct {
+ i int
+ B
+}
+
+type F int
+
+func (f F) Format(s State, c rune) {
+ Fprintf(s, "<%c=F(%d)>", c, int(f))
+}
+
+type G int
+
+func (g G) GoString() string {
+ return Sprintf("GoString(%d)", int(g))
+}
+
+type S struct {
+ F F // a struct field that Formats
+ G G // a struct field that GoStrings
+}
+
+type SI struct {
+ I any
+}
+
+// P is a type with a String method with pointer receiver for testing %p.
+type P int
+
+var pValue P
+
+func (p *P) String() string {
+ return "String(p)"
+}
+
+// Fn is a function type with a String method.
+type Fn func() int
+
+func (fn Fn) String() string { return "String(fn)" }
+
+var fnValue Fn
+
+// U is a type with two unexported function fields.
+type U struct {
+ u func() string
+ fn Fn
+}
+
+var barray = [5]renamedUint8{1, 2, 3, 4, 5}
+var bslice = barray[:]
+
+type byteStringer byte
+
+func (byteStringer) String() string {
+ return "X"
+}
+
+var byteStringerSlice = []byteStringer{'h', 'e', 'l', 'l', 'o'}
+
+type byteFormatter byte
+
+func (byteFormatter) Format(f State, _ rune) {
+ Fprint(f, "X")
+}
+
+var byteFormatterSlice = []byteFormatter{'h', 'e', 'l', 'l', 'o'}
+
+type writeStringFormatter string
+
+func (sf writeStringFormatter) Format(f State, c rune) {
+ if sw, ok := f.(io.StringWriter); ok {
+ sw.WriteString("***" + string(sf) + "***")
+ }
+}
+
+var fmtTests = []struct {
+ fmt string
+ val any
+ out string
+}{
+ {"%d", 12345, "12345"},
+ {"%v", 12345, "12345"},
+ {"%t", true, "true"},
+
+ // basic string
+ {"%s", "abc", "abc"},
+ {"%q", "abc", `"abc"`},
+ {"%x", "abc", "616263"},
+ {"%x", "\xff\xf0\x0f\xff", "fff00fff"},
+ {"%X", "\xff\xf0\x0f\xff", "FFF00FFF"},
+ {"%x", "", ""},
+ {"% x", "", ""},
+ {"%#x", "", ""},
+ {"%# x", "", ""},
+ {"%x", "xyz", "78797a"},
+ {"%X", "xyz", "78797A"},
+ {"% x", "xyz", "78 79 7a"},
+ {"% X", "xyz", "78 79 7A"},
+ {"%#x", "xyz", "0x78797a"},
+ {"%#X", "xyz", "0X78797A"},
+ {"%# x", "xyz", "0x78 0x79 0x7a"},
+ {"%# X", "xyz", "0X78 0X79 0X7A"},
+
+ // basic bytes
+ {"%s", []byte("abc"), "abc"},
+ {"%s", [3]byte{'a', 'b', 'c'}, "abc"},
+ {"%s", &[3]byte{'a', 'b', 'c'}, "&abc"},
+ {"%q", []byte("abc"), `"abc"`},
+ {"%x", []byte("abc"), "616263"},
+ {"%x", []byte("\xff\xf0\x0f\xff"), "fff00fff"},
+ {"%X", []byte("\xff\xf0\x0f\xff"), "FFF00FFF"},
+ {"%x", []byte(""), ""},
+ {"% x", []byte(""), ""},
+ {"%#x", []byte(""), ""},
+ {"%# x", []byte(""), ""},
+ {"%x", []byte("xyz"), "78797a"},
+ {"%X", []byte("xyz"), "78797A"},
+ {"% x", []byte("xyz"), "78 79 7a"},
+ {"% X", []byte("xyz"), "78 79 7A"},
+ {"%#x", []byte("xyz"), "0x78797a"},
+ {"%#X", []byte("xyz"), "0X78797A"},
+ {"%# x", []byte("xyz"), "0x78 0x79 0x7a"},
+ {"%# X", []byte("xyz"), "0X78 0X79 0X7A"},
+
+ // escaped strings
+ {"%q", "", `""`},
+ {"%#q", "", "``"},
+ {"%q", "\"", `"\""`},
+ {"%#q", "\"", "`\"`"},
+ {"%q", "`", `"` + "`" + `"`},
+ {"%#q", "`", `"` + "`" + `"`},
+ {"%q", "\n", `"\n"`},
+ {"%#q", "\n", `"\n"`},
+ {"%q", `\n`, `"\\n"`},
+ {"%#q", `\n`, "`\\n`"},
+ {"%q", "abc", `"abc"`},
+ {"%#q", "abc", "`abc`"},
+ {"%q", "日本語", `"日本語"`},
+ {"%+q", "日本語", `"\u65e5\u672c\u8a9e"`},
+ {"%#q", "日本語", "`日本語`"},
+ {"%#+q", "日本語", "`日本語`"},
+ {"%q", "\a\b\f\n\r\t\v\"\\", `"\a\b\f\n\r\t\v\"\\"`},
+ {"%+q", "\a\b\f\n\r\t\v\"\\", `"\a\b\f\n\r\t\v\"\\"`},
+ {"%#q", "\a\b\f\n\r\t\v\"\\", `"\a\b\f\n\r\t\v\"\\"`},
+ {"%#+q", "\a\b\f\n\r\t\v\"\\", `"\a\b\f\n\r\t\v\"\\"`},
+ {"%q", "☺", `"☺"`},
+ {"% q", "☺", `"☺"`}, // The space modifier should have no effect.
+ {"%+q", "☺", `"\u263a"`},
+ {"%#q", "☺", "`☺`"},
+ {"%#+q", "☺", "`☺`"},
+ {"%10q", "⌘", ` "⌘"`},
+ {"%+10q", "⌘", ` "\u2318"`},
+ {"%-10q", "⌘", `"⌘" `},
+ {"%+-10q", "⌘", `"\u2318" `},
+ {"%010q", "⌘", `0000000"⌘"`},
+ {"%+010q", "⌘", `00"\u2318"`},
+ {"%-010q", "⌘", `"⌘" `}, // 0 has no effect when - is present.
+ {"%+-010q", "⌘", `"\u2318" `},
+ {"%#8q", "\n", ` "\n"`},
+ {"%#+8q", "\r", ` "\r"`},
+ {"%#-8q", "\t", "` ` "},
+ {"%#+-8q", "\b", `"\b" `},
+ {"%q", "abc\xffdef", `"abc\xffdef"`},
+ {"%+q", "abc\xffdef", `"abc\xffdef"`},
+ {"%#q", "abc\xffdef", `"abc\xffdef"`},
+ {"%#+q", "abc\xffdef", `"abc\xffdef"`},
+ // Runes that are not printable.
+ {"%q", "\U0010ffff", `"\U0010ffff"`},
+ {"%+q", "\U0010ffff", `"\U0010ffff"`},
+ {"%#q", "\U0010ffff", "``"},
+ {"%#+q", "\U0010ffff", "``"},
+ // Runes that are not valid.
+ {"%q", string(rune(0x110000)), `"�"`},
+ {"%+q", string(rune(0x110000)), `"\ufffd"`},
+ {"%#q", string(rune(0x110000)), "`�`"},
+ {"%#+q", string(rune(0x110000)), "`�`"},
+
+ // characters
+ {"%c", uint('x'), "x"},
+ {"%c", 0xe4, "ä"},
+ {"%c", 0x672c, "本"},
+ {"%c", '日', "日"},
+ {"%.0c", '⌘', "⌘"}, // Specifying precision should have no effect.
+ {"%3c", '⌘', " ⌘"},
+ {"%-3c", '⌘', "⌘ "},
+ {"%c", uint64(0x100000000), "\ufffd"},
+ // Runes that are not printable.
+ {"%c", '\U00000e00', "\u0e00"},
+ {"%c", '\U0010ffff', "\U0010ffff"},
+ // Runes that are not valid.
+ {"%c", -1, "�"},
+ {"%c", 0xDC80, "�"},
+ {"%c", rune(0x110000), "�"},
+ {"%c", int64(0xFFFFFFFFF), "�"},
+ {"%c", uint64(0xFFFFFFFFF), "�"},
+
+ // escaped characters
+ {"%q", uint(0), `'\x00'`},
+ {"%+q", uint(0), `'\x00'`},
+ {"%q", '"', `'"'`},
+ {"%+q", '"', `'"'`},
+ {"%q", '\'', `'\''`},
+ {"%+q", '\'', `'\''`},
+ {"%q", '`', "'`'"},
+ {"%+q", '`', "'`'"},
+ {"%q", 'x', `'x'`},
+ {"%+q", 'x', `'x'`},
+ {"%q", 'ÿ', `'ÿ'`},
+ {"%+q", 'ÿ', `'\u00ff'`},
+ {"%q", '\n', `'\n'`},
+ {"%+q", '\n', `'\n'`},
+ {"%q", '☺', `'☺'`},
+ {"%+q", '☺', `'\u263a'`},
+ {"% q", '☺', `'☺'`}, // The space modifier should have no effect.
+ {"%.0q", '☺', `'☺'`}, // Specifying precision should have no effect.
+ {"%10q", '⌘', ` '⌘'`},
+ {"%+10q", '⌘', ` '\u2318'`},
+ {"%-10q", '⌘', `'⌘' `},
+ {"%+-10q", '⌘', `'\u2318' `},
+ {"%010q", '⌘', `0000000'⌘'`},
+ {"%+010q", '⌘', `00'\u2318'`},
+ {"%-010q", '⌘', `'⌘' `}, // 0 has no effect when - is present.
+ {"%+-010q", '⌘', `'\u2318' `},
+ // Runes that are not printable.
+ {"%q", '\U00000e00', `'\u0e00'`},
+ {"%q", '\U0010ffff', `'\U0010ffff'`},
+ // Runes that are not valid.
+ {"%q", int32(-1), `'�'`},
+ {"%q", 0xDC80, `'�'`},
+ {"%q", rune(0x110000), `'�'`},
+ {"%q", int64(0xFFFFFFFFF), `'�'`},
+ {"%q", uint64(0xFFFFFFFFF), `'�'`},
+
+ // width
+ {"%5s", "abc", " abc"},
+ {"%5s", []byte("abc"), " abc"},
+ {"%2s", "\u263a", " ☺"},
+ {"%2s", []byte("\u263a"), " ☺"},
+ {"%-5s", "abc", "abc "},
+ {"%-5s", []byte("abc"), "abc "},
+ {"%05s", "abc", "00abc"},
+ {"%05s", []byte("abc"), "00abc"},
+ {"%5s", "abcdefghijklmnopqrstuvwxyz", "abcdefghijklmnopqrstuvwxyz"},
+ {"%5s", []byte("abcdefghijklmnopqrstuvwxyz"), "abcdefghijklmnopqrstuvwxyz"},
+ {"%.5s", "abcdefghijklmnopqrstuvwxyz", "abcde"},
+ {"%.5s", []byte("abcdefghijklmnopqrstuvwxyz"), "abcde"},
+ {"%.0s", "日本語日本語", ""},
+ {"%.0s", []byte("日本語日本語"), ""},
+ {"%.5s", "日本語日本語", "日本語日本"},
+ {"%.5s", []byte("日本語日本語"), "日本語日本"},
+ {"%.10s", "日本語日本語", "日本語日本語"},
+ {"%.10s", []byte("日本語日本語"), "日本語日本語"},
+ {"%08q", "abc", `000"abc"`},
+ {"%08q", []byte("abc"), `000"abc"`},
+ {"%-8q", "abc", `"abc" `},
+ {"%-8q", []byte("abc"), `"abc" `},
+ {"%.5q", "abcdefghijklmnopqrstuvwxyz", `"abcde"`},
+ {"%.5q", []byte("abcdefghijklmnopqrstuvwxyz"), `"abcde"`},
+ {"%.5x", "abcdefghijklmnopqrstuvwxyz", "6162636465"},
+ {"%.5x", []byte("abcdefghijklmnopqrstuvwxyz"), "6162636465"},
+ {"%.3q", "日本語日本語", `"日本語"`},
+ {"%.3q", []byte("日本語日本語"), `"日本語"`},
+ {"%.1q", "日本語", `"日"`},
+ {"%.1q", []byte("日本語"), `"日"`},
+ {"%.1x", "日本語", "e6"},
+ {"%.1X", []byte("日本語"), "E6"},
+ {"%10.1q", "日本語日本語", ` "日"`},
+ {"%10.1q", []byte("日本語日本語"), ` "日"`},
+ {"%10v", nil, " "},
+ {"%-10v", nil, " "},
+
+ // integers
+ {"%d", uint(12345), "12345"},
+ {"%d", int(-12345), "-12345"},
+ {"%d", ^uint8(0), "255"},
+ {"%d", ^uint16(0), "65535"},
+ {"%d", ^uint32(0), "4294967295"},
+ {"%d", ^uint64(0), "18446744073709551615"},
+ {"%d", int8(-1 << 7), "-128"},
+ {"%d", int16(-1 << 15), "-32768"},
+ {"%d", int32(-1 << 31), "-2147483648"},
+ {"%d", int64(-1 << 63), "-9223372036854775808"},
+ {"%.d", 0, ""},
+ {"%.0d", 0, ""},
+ {"%6.0d", 0, " "},
+ {"%06.0d", 0, " "},
+ {"% d", 12345, " 12345"},
+ {"%+d", 12345, "+12345"},
+ {"%+d", -12345, "-12345"},
+ {"%b", 7, "111"},
+ {"%b", -6, "-110"},
+ {"%#b", 7, "0b111"},
+ {"%#b", -6, "-0b110"},
+ {"%b", ^uint32(0), "11111111111111111111111111111111"},
+ {"%b", ^uint64(0), "1111111111111111111111111111111111111111111111111111111111111111"},
+ {"%b", int64(-1 << 63), zeroFill("-1", 63, "")},
+ {"%o", 01234, "1234"},
+ {"%o", -01234, "-1234"},
+ {"%#o", 01234, "01234"},
+ {"%#o", -01234, "-01234"},
+ {"%O", 01234, "0o1234"},
+ {"%O", -01234, "-0o1234"},
+ {"%o", ^uint32(0), "37777777777"},
+ {"%o", ^uint64(0), "1777777777777777777777"},
+ {"%#X", 0, "0X0"},
+ {"%x", 0x12abcdef, "12abcdef"},
+ {"%X", 0x12abcdef, "12ABCDEF"},
+ {"%x", ^uint32(0), "ffffffff"},
+ {"%X", ^uint64(0), "FFFFFFFFFFFFFFFF"},
+ {"%.20b", 7, "00000000000000000111"},
+ {"%10d", 12345, " 12345"},
+ {"%10d", -12345, " -12345"},
+ {"%+10d", 12345, " +12345"},
+ {"%010d", 12345, "0000012345"},
+ {"%010d", -12345, "-000012345"},
+ {"%20.8d", 1234, " 00001234"},
+ {"%20.8d", -1234, " -00001234"},
+ {"%020.8d", 1234, " 00001234"},
+ {"%020.8d", -1234, " -00001234"},
+ {"%-20.8d", 1234, "00001234 "},
+ {"%-20.8d", -1234, "-00001234 "},
+ {"%-#20.8x", 0x1234abc, "0x01234abc "},
+ {"%-#20.8X", 0x1234abc, "0X01234ABC "},
+ {"%-#20.8o", 01234, "00001234 "},
+
+ // Test correct f.intbuf overflow checks.
+ {"%068d", 1, zeroFill("", 68, "1")},
+ {"%068d", -1, zeroFill("-", 67, "1")},
+ {"%#.68x", 42, zeroFill("0x", 68, "2a")},
+ {"%.68d", -42, zeroFill("-", 68, "42")},
+ {"%+.68d", 42, zeroFill("+", 68, "42")},
+ {"% .68d", 42, zeroFill(" ", 68, "42")},
+ {"% +.68d", 42, zeroFill("+", 68, "42")},
+
+ // unicode format
+ {"%U", 0, "U+0000"},
+ {"%U", -1, "U+FFFFFFFFFFFFFFFF"},
+ {"%U", '\n', `U+000A`},
+ {"%#U", '\n', `U+000A`},
+ {"%+U", 'x', `U+0078`}, // Plus flag should have no effect.
+ {"%# U", 'x', `U+0078 'x'`}, // Space flag should have no effect.
+ {"%#.2U", 'x', `U+0078 'x'`}, // Precisions below 4 should print 4 digits.
+ {"%U", '\u263a', `U+263A`},
+ {"%#U", '\u263a', `U+263A '☺'`},
+ {"%U", '\U0001D6C2', `U+1D6C2`},
+ {"%#U", '\U0001D6C2', `U+1D6C2 '𝛂'`},
+ {"%#14.6U", '⌘', " U+002318 '⌘'"},
+ {"%#-14.6U", '⌘', "U+002318 '⌘' "},
+ {"%#014.6U", '⌘', " U+002318 '⌘'"},
+ {"%#-014.6U", '⌘', "U+002318 '⌘' "},
+ {"%.68U", uint(42), zeroFill("U+", 68, "2A")},
+ {"%#.68U", '日', zeroFill("U+", 68, "65E5") + " '日'"},
+
+ // floats
+ {"%+.3e", 0.0, "+0.000e+00"},
+ {"%+.3e", 1.0, "+1.000e+00"},
+ {"%+.3x", 0.0, "+0x0.000p+00"},
+ {"%+.3x", 1.0, "+0x1.000p+00"},
+ {"%+.3f", -1.0, "-1.000"},
+ {"%+.3F", -1.0, "-1.000"},
+ {"%+.3F", float32(-1.0), "-1.000"},
+ {"%+07.2f", 1.0, "+001.00"},
+ {"%+07.2f", -1.0, "-001.00"},
+ {"%-07.2f", 1.0, "1.00 "},
+ {"%-07.2f", -1.0, "-1.00 "},
+ {"%+-07.2f", 1.0, "+1.00 "},
+ {"%+-07.2f", -1.0, "-1.00 "},
+ {"%-+07.2f", 1.0, "+1.00 "},
+ {"%-+07.2f", -1.0, "-1.00 "},
+ {"%+10.2f", +1.0, " +1.00"},
+ {"%+10.2f", -1.0, " -1.00"},
+ {"% .3E", -1.0, "-1.000E+00"},
+ {"% .3e", 1.0, " 1.000e+00"},
+ {"% .3X", -1.0, "-0X1.000P+00"},
+ {"% .3x", 1.0, " 0x1.000p+00"},
+ {"%+.3g", 0.0, "+0"},
+ {"%+.3g", 1.0, "+1"},
+ {"%+.3g", -1.0, "-1"},
+ {"% .3g", -1.0, "-1"},
+ {"% .3g", 1.0, " 1"},
+ {"%b", float32(1.0), "8388608p-23"},
+ {"%b", 1.0, "4503599627370496p-52"},
+ // Test sharp flag used with floats.
+ {"%#g", 1e-323, "1.00000e-323"},
+ {"%#g", -1.0, "-1.00000"},
+ {"%#g", 1.1, "1.10000"},
+ {"%#g", 123456.0, "123456."},
+ {"%#g", 1234567.0, "1.234567e+06"},
+ {"%#g", 1230000.0, "1.23000e+06"},
+ {"%#g", 1000000.0, "1.00000e+06"},
+ {"%#.0f", 1.0, "1."},
+ {"%#.0e", 1.0, "1.e+00"},
+ {"%#.0x", 1.0, "0x1.p+00"},
+ {"%#.0g", 1.0, "1."},
+ {"%#.0g", 1100000.0, "1.e+06"},
+ {"%#.4f", 1.0, "1.0000"},
+ {"%#.4e", 1.0, "1.0000e+00"},
+ {"%#.4x", 1.0, "0x1.0000p+00"},
+ {"%#.4g", 1.0, "1.000"},
+ {"%#.4g", 100000.0, "1.000e+05"},
+ {"%#.4g", 1.234, "1.234"},
+ {"%#.4g", 0.1234, "0.1234"},
+ {"%#.4g", 1.23, "1.230"},
+ {"%#.4g", 0.123, "0.1230"},
+ {"%#.4g", 1.2, "1.200"},
+ {"%#.4g", 0.12, "0.1200"},
+ {"%#.4g", 10.2, "10.20"},
+ {"%#.4g", 0.0, "0.000"},
+ {"%#.4g", 0.012, "0.01200"},
+ {"%#.0f", 123.0, "123."},
+ {"%#.0e", 123.0, "1.e+02"},
+ {"%#.0x", 123.0, "0x1.p+07"},
+ {"%#.0g", 123.0, "1.e+02"},
+ {"%#.4f", 123.0, "123.0000"},
+ {"%#.4e", 123.0, "1.2300e+02"},
+ {"%#.4x", 123.0, "0x1.ec00p+06"},
+ {"%#.4g", 123.0, "123.0"},
+ {"%#.4g", 123000.0, "1.230e+05"},
+ {"%#9.4g", 1.0, " 1.000"},
+ // The sharp flag has no effect for binary float format.
+ {"%#b", 1.0, "4503599627370496p-52"},
+ // Precision has no effect for binary float format.
+ {"%.4b", float32(1.0), "8388608p-23"},
+ {"%.4b", -1.0, "-4503599627370496p-52"},
+ // Test correct f.intbuf boundary checks.
+ {"%.68f", 1.0, zeroFill("1.", 68, "")},
+ {"%.68f", -1.0, zeroFill("-1.", 68, "")},
+ // float infinites and NaNs
+ {"%f", posInf, "+Inf"},
+ {"%.1f", negInf, "-Inf"},
+ {"% f", NaN, " NaN"},
+ {"%20f", posInf, " +Inf"},
+ {"% 20F", posInf, " Inf"},
+ {"% 20e", negInf, " -Inf"},
+ {"% 20x", negInf, " -Inf"},
+ {"%+20E", negInf, " -Inf"},
+ {"%+20X", negInf, " -Inf"},
+ {"% +20g", negInf, " -Inf"},
+ {"%+-20G", posInf, "+Inf "},
+ {"%20e", NaN, " NaN"},
+ {"%20x", NaN, " NaN"},
+ {"% +20E", NaN, " +NaN"},
+ {"% +20X", NaN, " +NaN"},
+ {"% -20g", NaN, " NaN "},
+ {"%+-20G", NaN, "+NaN "},
+ // Zero padding does not apply to infinities and NaN.
+ {"%+020e", posInf, " +Inf"},
+ {"%+020x", posInf, " +Inf"},
+ {"%-020f", negInf, "-Inf "},
+ {"%-020E", NaN, "NaN "},
+ {"%-020X", NaN, "NaN "},
+
+ // complex values
+ {"%.f", 0i, "(0+0i)"},
+ {"% .f", 0i, "( 0+0i)"},
+ {"%+.f", 0i, "(+0+0i)"},
+ {"% +.f", 0i, "(+0+0i)"},
+ {"%+.3e", 0i, "(+0.000e+00+0.000e+00i)"},
+ {"%+.3x", 0i, "(+0x0.000p+00+0x0.000p+00i)"},
+ {"%+.3f", 0i, "(+0.000+0.000i)"},
+ {"%+.3g", 0i, "(+0+0i)"},
+ {"%+.3e", 1 + 2i, "(+1.000e+00+2.000e+00i)"},
+ {"%+.3x", 1 + 2i, "(+0x1.000p+00+0x1.000p+01i)"},
+ {"%+.3f", 1 + 2i, "(+1.000+2.000i)"},
+ {"%+.3g", 1 + 2i, "(+1+2i)"},
+ {"%.3e", 0i, "(0.000e+00+0.000e+00i)"},
+ {"%.3x", 0i, "(0x0.000p+00+0x0.000p+00i)"},
+ {"%.3f", 0i, "(0.000+0.000i)"},
+ {"%.3F", 0i, "(0.000+0.000i)"},
+ {"%.3F", complex64(0i), "(0.000+0.000i)"},
+ {"%.3g", 0i, "(0+0i)"},
+ {"%.3e", 1 + 2i, "(1.000e+00+2.000e+00i)"},
+ {"%.3x", 1 + 2i, "(0x1.000p+00+0x1.000p+01i)"},
+ {"%.3f", 1 + 2i, "(1.000+2.000i)"},
+ {"%.3g", 1 + 2i, "(1+2i)"},
+ {"%.3e", -1 - 2i, "(-1.000e+00-2.000e+00i)"},
+ {"%.3x", -1 - 2i, "(-0x1.000p+00-0x1.000p+01i)"},
+ {"%.3f", -1 - 2i, "(-1.000-2.000i)"},
+ {"%.3g", -1 - 2i, "(-1-2i)"},
+ {"% .3E", -1 - 2i, "(-1.000E+00-2.000E+00i)"},
+ {"% .3X", -1 - 2i, "(-0X1.000P+00-0X1.000P+01i)"},
+ {"%+.3g", 1 + 2i, "(+1+2i)"},
+ {"%+.3g", complex64(1 + 2i), "(+1+2i)"},
+ {"%#g", 1 + 2i, "(1.00000+2.00000i)"},
+ {"%#g", 123456 + 789012i, "(123456.+789012.i)"},
+ {"%#g", 1e-10i, "(0.00000+1.00000e-10i)"},
+ {"%#g", -1e10 - 1.11e100i, "(-1.00000e+10-1.11000e+100i)"},
+ {"%#.0f", 1.23 + 1.0i, "(1.+1.i)"},
+ {"%#.0e", 1.23 + 1.0i, "(1.e+00+1.e+00i)"},
+ {"%#.0x", 1.23 + 1.0i, "(0x1.p+00+0x1.p+00i)"},
+ {"%#.0g", 1.23 + 1.0i, "(1.+1.i)"},
+ {"%#.0g", 0 + 100000i, "(0.+1.e+05i)"},
+ {"%#.0g", 1230000 + 0i, "(1.e+06+0.i)"},
+ {"%#.4f", 1 + 1.23i, "(1.0000+1.2300i)"},
+ {"%#.4e", 123 + 1i, "(1.2300e+02+1.0000e+00i)"},
+ {"%#.4x", 123 + 1i, "(0x1.ec00p+06+0x1.0000p+00i)"},
+ {"%#.4g", 123 + 1.23i, "(123.0+1.230i)"},
+ {"%#12.5g", 0 + 100000i, "( 0.0000 +1.0000e+05i)"},
+ {"%#12.5g", 1230000 - 0i, "( 1.2300e+06 +0.0000i)"},
+ {"%b", 1 + 2i, "(4503599627370496p-52+4503599627370496p-51i)"},
+ {"%b", complex64(1 + 2i), "(8388608p-23+8388608p-22i)"},
+ // The sharp flag has no effect for binary complex format.
+ {"%#b", 1 + 2i, "(4503599627370496p-52+4503599627370496p-51i)"},
+ // Precision has no effect for binary complex format.
+ {"%.4b", 1 + 2i, "(4503599627370496p-52+4503599627370496p-51i)"},
+ {"%.4b", complex64(1 + 2i), "(8388608p-23+8388608p-22i)"},
+ // complex infinites and NaNs
+ {"%f", complex(posInf, posInf), "(+Inf+Infi)"},
+ {"%f", complex(negInf, negInf), "(-Inf-Infi)"},
+ {"%f", complex(NaN, NaN), "(NaN+NaNi)"},
+ {"%.1f", complex(posInf, posInf), "(+Inf+Infi)"},
+ {"% f", complex(posInf, posInf), "( Inf+Infi)"},
+ {"% f", complex(negInf, negInf), "(-Inf-Infi)"},
+ {"% f", complex(NaN, NaN), "( NaN+NaNi)"},
+ {"%8e", complex(posInf, posInf), "( +Inf +Infi)"},
+ {"%8x", complex(posInf, posInf), "( +Inf +Infi)"},
+ {"% 8E", complex(posInf, posInf), "( Inf +Infi)"},
+ {"% 8X", complex(posInf, posInf), "( Inf +Infi)"},
+ {"%+8f", complex(negInf, negInf), "( -Inf -Infi)"},
+ {"% +8g", complex(negInf, negInf), "( -Inf -Infi)"},
+ {"% -8G", complex(NaN, NaN), "( NaN +NaN i)"},
+ {"%+-8b", complex(NaN, NaN), "(+NaN +NaN i)"},
+ // Zero padding does not apply to infinities and NaN.
+ {"%08f", complex(posInf, posInf), "( +Inf +Infi)"},
+ {"%-08g", complex(negInf, negInf), "(-Inf -Inf i)"},
+ {"%-08G", complex(NaN, NaN), "(NaN +NaN i)"},
+
+ // old test/fmt_test.go
+ {"%e", 1.0, "1.000000e+00"},
+ {"%e", 1234.5678e3, "1.234568e+06"},
+ {"%e", 1234.5678e-8, "1.234568e-05"},
+ {"%e", -7.0, "-7.000000e+00"},
+ {"%e", -1e-9, "-1.000000e-09"},
+ {"%f", 1234.5678e3, "1234567.800000"},
+ {"%f", 1234.5678e-8, "0.000012"},
+ {"%f", -7.0, "-7.000000"},
+ {"%f", -1e-9, "-0.000000"},
+ {"%g", 1234.5678e3, "1.2345678e+06"},
+ {"%g", float32(1234.5678e3), "1.2345678e+06"},
+ {"%g", 1234.5678e-8, "1.2345678e-05"},
+ {"%g", -7.0, "-7"},
+ {"%g", -1e-9, "-1e-09"},
+ {"%g", float32(-1e-9), "-1e-09"},
+ {"%E", 1.0, "1.000000E+00"},
+ {"%E", 1234.5678e3, "1.234568E+06"},
+ {"%E", 1234.5678e-8, "1.234568E-05"},
+ {"%E", -7.0, "-7.000000E+00"},
+ {"%E", -1e-9, "-1.000000E-09"},
+ {"%G", 1234.5678e3, "1.2345678E+06"},
+ {"%G", float32(1234.5678e3), "1.2345678E+06"},
+ {"%G", 1234.5678e-8, "1.2345678E-05"},
+ {"%G", -7.0, "-7"},
+ {"%G", -1e-9, "-1E-09"},
+ {"%G", float32(-1e-9), "-1E-09"},
+ {"%20.5s", "qwertyuiop", " qwert"},
+ {"%.5s", "qwertyuiop", "qwert"},
+ {"%-20.5s", "qwertyuiop", "qwert "},
+ {"%20c", 'x', " x"},
+ {"%-20c", 'x', "x "},
+ {"%20.6e", 1.2345e3, " 1.234500e+03"},
+ {"%20.6e", 1.2345e-3, " 1.234500e-03"},
+ {"%20e", 1.2345e3, " 1.234500e+03"},
+ {"%20e", 1.2345e-3, " 1.234500e-03"},
+ {"%20.8e", 1.2345e3, " 1.23450000e+03"},
+ {"%20f", 1.23456789e3, " 1234.567890"},
+ {"%20f", 1.23456789e-3, " 0.001235"},
+ {"%20f", 12345678901.23456789, " 12345678901.234568"},
+ {"%-20f", 1.23456789e3, "1234.567890 "},
+ {"%20.8f", 1.23456789e3, " 1234.56789000"},
+ {"%20.8f", 1.23456789e-3, " 0.00123457"},
+ {"%g", 1.23456789e3, "1234.56789"},
+ {"%g", 1.23456789e-3, "0.00123456789"},
+ {"%g", 1.23456789e20, "1.23456789e+20"},
+
+ // arrays
+ {"%v", array, "[1 2 3 4 5]"},
+ {"%v", iarray, "[1 hello 2.5 ]"},
+ {"%v", barray, "[1 2 3 4 5]"},
+ {"%v", &array, "&[1 2 3 4 5]"},
+ {"%v", &iarray, "&[1 hello 2.5 ]"},
+ {"%v", &barray, "&[1 2 3 4 5]"},
+
+ // slices
+ {"%v", slice, "[1 2 3 4 5]"},
+ {"%v", islice, "[1 hello 2.5 ]"},
+ {"%v", bslice, "[1 2 3 4 5]"},
+ {"%v", &slice, "&[1 2 3 4 5]"},
+ {"%v", &islice, "&[1 hello 2.5 ]"},
+ {"%v", &bslice, "&[1 2 3 4 5]"},
+
+ // byte arrays and slices with %b,%c,%d,%o,%U and %v
+ {"%b", [3]byte{65, 66, 67}, "[1000001 1000010 1000011]"},
+ {"%c", [3]byte{65, 66, 67}, "[A B C]"},
+ {"%d", [3]byte{65, 66, 67}, "[65 66 67]"},
+ {"%o", [3]byte{65, 66, 67}, "[101 102 103]"},
+ {"%U", [3]byte{65, 66, 67}, "[U+0041 U+0042 U+0043]"},
+ {"%v", [3]byte{65, 66, 67}, "[65 66 67]"},
+ {"%v", [1]byte{123}, "[123]"},
+ {"%012v", []byte{}, "[]"},
+ {"%#012v", []byte{}, "[]byte{}"},
+ {"%6v", []byte{1, 11, 111}, "[ 1 11 111]"},
+ {"%06v", []byte{1, 11, 111}, "[000001 000011 000111]"},
+ {"%-6v", []byte{1, 11, 111}, "[1 11 111 ]"},
+ {"%-06v", []byte{1, 11, 111}, "[1 11 111 ]"},
+ {"%#v", []byte{1, 11, 111}, "[]byte{0x1, 0xb, 0x6f}"},
+ {"%#6v", []byte{1, 11, 111}, "[]byte{ 0x1, 0xb, 0x6f}"},
+ {"%#06v", []byte{1, 11, 111}, "[]byte{0x000001, 0x00000b, 0x00006f}"},
+ {"%#-6v", []byte{1, 11, 111}, "[]byte{0x1 , 0xb , 0x6f }"},
+ {"%#-06v", []byte{1, 11, 111}, "[]byte{0x1 , 0xb , 0x6f }"},
+ // f.space should and f.plus should not have an effect with %v.
+ {"% v", []byte{1, 11, 111}, "[ 1 11 111]"},
+ {"%+v", [3]byte{1, 11, 111}, "[1 11 111]"},
+ {"%# -6v", []byte{1, 11, 111}, "[]byte{ 0x1 , 0xb , 0x6f }"},
+ {"%#+-6v", [3]byte{1, 11, 111}, "[3]uint8{0x1 , 0xb , 0x6f }"},
+ // f.space and f.plus should have an effect with %d.
+ {"% d", []byte{1, 11, 111}, "[ 1 11 111]"},
+ {"%+d", [3]byte{1, 11, 111}, "[+1 +11 +111]"},
+ {"%# -6d", []byte{1, 11, 111}, "[ 1 11 111 ]"},
+ {"%#+-6d", [3]byte{1, 11, 111}, "[+1 +11 +111 ]"},
+
+ // floates with %v
+ {"%v", 1.2345678, "1.2345678"},
+ {"%v", float32(1.2345678), "1.2345678"},
+
+ // complexes with %v
+ {"%v", 1 + 2i, "(1+2i)"},
+ {"%v", complex64(1 + 2i), "(1+2i)"},
+
+ // structs
+ {"%v", A{1, 2, "a", []int{1, 2}}, `{1 2 a [1 2]}`},
+ {"%+v", A{1, 2, "a", []int{1, 2}}, `{i:1 j:2 s:a x:[1 2]}`},
+
+ // +v on structs with Stringable items
+ {"%+v", B{1, 2}, `{I:<1> j:2}`},
+ {"%+v", C{1, B{2, 3}}, `{i:1 B:{I:<2> j:3}}`},
+
+ // other formats on Stringable items
+ {"%s", I(23), `<23>`},
+ {"%q", I(23), `"<23>"`},
+ {"%x", I(23), `3c32333e`},
+ {"%#x", I(23), `0x3c32333e`},
+ {"%# x", I(23), `0x3c 0x32 0x33 0x3e`},
+ // Stringer applies only to string formats.
+ {"%d", I(23), `23`},
+ // Stringer applies to the extracted value.
+ {"%s", reflect.ValueOf(I(23)), `<23>`},
+
+ // go syntax
+ {"%#v", A{1, 2, "a", []int{1, 2}}, `fmt_test.A{i:1, j:0x2, s:"a", x:[]int{1, 2}}`},
+ {"%#v", new(byte), "(*uint8)(0xPTR)"},
+ {"%#v", make(chan int), "(chan int)(0xPTR)"},
+ {"%#v", uint64(1<<64 - 1), "0xffffffffffffffff"},
+ {"%#v", 1000000000, "1000000000"},
+ {"%#v", map[string]int{"a": 1}, `map[string]int{"a":1}`},
+ {"%#v", map[string]B{"a": {1, 2}}, `map[string]fmt_test.B{"a":fmt_test.B{I:1, j:2}}`},
+ {"%#v", []string{"a", "b"}, `[]string{"a", "b"}`},
+ {"%#v", SI{}, `fmt_test.SI{I:interface {}(nil)}`},
+ {"%#v", []int(nil), `[]int(nil)`},
+ {"%#v", []int{}, `[]int{}`},
+ {"%#v", array, `[5]int{1, 2, 3, 4, 5}`},
+ {"%#v", &array, `&[5]int{1, 2, 3, 4, 5}`},
+ {"%#v", iarray, `[4]interface {}{1, "hello", 2.5, interface {}(nil)}`},
+ {"%#v", &iarray, `&[4]interface {}{1, "hello", 2.5, interface {}(nil)}`},
+ {"%#v", map[int]byte(nil), `map[int]uint8(nil)`},
+ {"%#v", map[int]byte{}, `map[int]uint8{}`},
+ {"%#v", "foo", `"foo"`},
+ {"%#v", barray, `[5]fmt_test.renamedUint8{0x1, 0x2, 0x3, 0x4, 0x5}`},
+ {"%#v", bslice, `[]fmt_test.renamedUint8{0x1, 0x2, 0x3, 0x4, 0x5}`},
+ {"%#v", []int32(nil), "[]int32(nil)"},
+ {"%#v", 1.2345678, "1.2345678"},
+ {"%#v", float32(1.2345678), "1.2345678"},
+
+ // functions
+ {"%v", TestFmtInterface, "0xPTR"}, // simple function
+ {"%v", reflect.ValueOf(TestFmtInterface), "0xPTR"},
+ {"%v", G.GoString, "0xPTR"}, // method expression
+ {"%v", reflect.ValueOf(G.GoString), "0xPTR"},
+ {"%v", G(23).GoString, "0xPTR"}, // method value
+ {"%v", reflect.ValueOf(G(23).GoString), "0xPTR"},
+ {"%v", reflect.ValueOf(G(23)).Method(0), "0xPTR"},
+ {"%v", Fn.String, "0xPTR"}, // method of function type
+ {"%v", reflect.ValueOf(Fn.String), "0xPTR"},
+ {"%v", fnValue, "String(fn)"}, // variable of function type with String method
+ {"%v", reflect.ValueOf(fnValue), "String(fn)"},
+ {"%v", [1]Fn{fnValue}, "[String(fn)]"}, // array of function type with String method
+ {"%v", reflect.ValueOf([1]Fn{fnValue}), "[String(fn)]"},
+ {"%v", fnValue.String, "0xPTR"}, // method value from function type
+ {"%v", reflect.ValueOf(fnValue.String), "0xPTR"},
+ {"%v", reflect.ValueOf(fnValue).Method(0), "0xPTR"},
+ {"%v", U{}.u, ""}, // unexported function field
+ {"%v", reflect.ValueOf(U{}.u), ""},
+ {"%v", reflect.ValueOf(U{}).Field(0), ""},
+ {"%v", U{fn: fnValue}.fn, "String(fn)"}, // unexported field of function type with String method
+ {"%v", reflect.ValueOf(U{fn: fnValue}.fn), "String(fn)"},
+ {"%v", reflect.ValueOf(U{fn: fnValue}).Field(1), ""},
+
+ // functions with go syntax
+ {"%#v", TestFmtInterface, "(func(*testing.T))(0xPTR)"}, // simple function
+ {"%#v", reflect.ValueOf(TestFmtInterface), "(func(*testing.T))(0xPTR)"},
+ {"%#v", G.GoString, "(func(fmt_test.G) string)(0xPTR)"}, // method expression
+ {"%#v", reflect.ValueOf(G.GoString), "(func(fmt_test.G) string)(0xPTR)"},
+ {"%#v", G(23).GoString, "(func() string)(0xPTR)"}, // method value
+ {"%#v", reflect.ValueOf(G(23).GoString), "(func() string)(0xPTR)"},
+ {"%#v", reflect.ValueOf(G(23)).Method(0), "(func() string)(0xPTR)"},
+ {"%#v", Fn.String, "(func(fmt_test.Fn) string)(0xPTR)"}, // method of function type
+ {"%#v", reflect.ValueOf(Fn.String), "(func(fmt_test.Fn) string)(0xPTR)"},
+ {"%#v", fnValue, "(fmt_test.Fn)(nil)"}, // variable of function type with String method
+ {"%#v", reflect.ValueOf(fnValue), "(fmt_test.Fn)(nil)"},
+ {"%#v", [1]Fn{fnValue}, "[1]fmt_test.Fn{(fmt_test.Fn)(nil)}"}, // array of function type with String method
+ {"%#v", reflect.ValueOf([1]Fn{fnValue}), "[1]fmt_test.Fn{(fmt_test.Fn)(nil)}"},
+ {"%#v", fnValue.String, "(func() string)(0xPTR)"}, // method value from function type
+ {"%#v", reflect.ValueOf(fnValue.String), "(func() string)(0xPTR)"},
+ {"%#v", reflect.ValueOf(fnValue).Method(0), "(func() string)(0xPTR)"},
+ {"%#v", U{}.u, "(func() string)(nil)"}, // unexported function field
+ {"%#v", reflect.ValueOf(U{}.u), "(func() string)(nil)"},
+ {"%#v", reflect.ValueOf(U{}).Field(0), "(func() string)(nil)"},
+ {"%#v", U{fn: fnValue}.fn, "(fmt_test.Fn)(nil)"}, // unexported field of function type with String method
+ {"%#v", reflect.ValueOf(U{fn: fnValue}.fn), "(fmt_test.Fn)(nil)"},
+ {"%#v", reflect.ValueOf(U{fn: fnValue}).Field(1), "(fmt_test.Fn)(nil)"},
+
+ // Whole number floats are printed without decimals. See Issue 27634.
+ {"%#v", 1.0, "1"},
+ {"%#v", 1000000.0, "1e+06"},
+ {"%#v", float32(1.0), "1"},
+ {"%#v", float32(1000000.0), "1e+06"},
+
+ // Only print []byte and []uint8 as type []byte if they appear at the top level.
+ {"%#v", []byte(nil), "[]byte(nil)"},
+ {"%#v", []uint8(nil), "[]byte(nil)"},
+ {"%#v", []byte{}, "[]byte{}"},
+ {"%#v", []uint8{}, "[]byte{}"},
+ {"%#v", reflect.ValueOf([]byte{}), "[]uint8{}"},
+ {"%#v", reflect.ValueOf([]uint8{}), "[]uint8{}"},
+ {"%#v", &[]byte{}, "&[]uint8{}"},
+ {"%#v", &[]byte{}, "&[]uint8{}"},
+ {"%#v", [3]byte{}, "[3]uint8{0x0, 0x0, 0x0}"},
+ {"%#v", [3]uint8{}, "[3]uint8{0x0, 0x0, 0x0}"},
+
+ // slices with other formats
+ {"%#x", []int{1, 2, 15}, `[0x1 0x2 0xf]`},
+ {"%x", []int{1, 2, 15}, `[1 2 f]`},
+ {"%d", []int{1, 2, 15}, `[1 2 15]`},
+ {"%d", []byte{1, 2, 15}, `[1 2 15]`},
+ {"%q", []string{"a", "b"}, `["a" "b"]`},
+ {"% 02x", []byte{1}, "01"},
+ {"% 02x", []byte{1, 2, 3}, "01 02 03"},
+
+ // Padding with byte slices.
+ {"%2x", []byte{}, " "},
+ {"%#2x", []byte{}, " "},
+ {"% 02x", []byte{}, "00"},
+ {"%# 02x", []byte{}, "00"},
+ {"%-2x", []byte{}, " "},
+ {"%-02x", []byte{}, " "},
+ {"%8x", []byte{0xab}, " ab"},
+ {"% 8x", []byte{0xab}, " ab"},
+ {"%#8x", []byte{0xab}, " 0xab"},
+ {"%# 8x", []byte{0xab}, " 0xab"},
+ {"%08x", []byte{0xab}, "000000ab"},
+ {"% 08x", []byte{0xab}, "000000ab"},
+ {"%#08x", []byte{0xab}, "00000xab"},
+ {"%# 08x", []byte{0xab}, "00000xab"},
+ {"%10x", []byte{0xab, 0xcd}, " abcd"},
+ {"% 10x", []byte{0xab, 0xcd}, " ab cd"},
+ {"%#10x", []byte{0xab, 0xcd}, " 0xabcd"},
+ {"%# 10x", []byte{0xab, 0xcd}, " 0xab 0xcd"},
+ {"%010x", []byte{0xab, 0xcd}, "000000abcd"},
+ {"% 010x", []byte{0xab, 0xcd}, "00000ab cd"},
+ {"%#010x", []byte{0xab, 0xcd}, "00000xabcd"},
+ {"%# 010x", []byte{0xab, 0xcd}, "00xab 0xcd"},
+ {"%-10X", []byte{0xab}, "AB "},
+ {"% -010X", []byte{0xab}, "AB "},
+ {"%#-10X", []byte{0xab, 0xcd}, "0XABCD "},
+ {"%# -010X", []byte{0xab, 0xcd}, "0XAB 0XCD "},
+ // Same for strings
+ {"%2x", "", " "},
+ {"%#2x", "", " "},
+ {"% 02x", "", "00"},
+ {"%# 02x", "", "00"},
+ {"%-2x", "", " "},
+ {"%-02x", "", " "},
+ {"%8x", "\xab", " ab"},
+ {"% 8x", "\xab", " ab"},
+ {"%#8x", "\xab", " 0xab"},
+ {"%# 8x", "\xab", " 0xab"},
+ {"%08x", "\xab", "000000ab"},
+ {"% 08x", "\xab", "000000ab"},
+ {"%#08x", "\xab", "00000xab"},
+ {"%# 08x", "\xab", "00000xab"},
+ {"%10x", "\xab\xcd", " abcd"},
+ {"% 10x", "\xab\xcd", " ab cd"},
+ {"%#10x", "\xab\xcd", " 0xabcd"},
+ {"%# 10x", "\xab\xcd", " 0xab 0xcd"},
+ {"%010x", "\xab\xcd", "000000abcd"},
+ {"% 010x", "\xab\xcd", "00000ab cd"},
+ {"%#010x", "\xab\xcd", "00000xabcd"},
+ {"%# 010x", "\xab\xcd", "00xab 0xcd"},
+ {"%-10X", "\xab", "AB "},
+ {"% -010X", "\xab", "AB "},
+ {"%#-10X", "\xab\xcd", "0XABCD "},
+ {"%# -010X", "\xab\xcd", "0XAB 0XCD "},
+
+ // renamings
+ {"%v", renamedBool(true), "true"},
+ {"%d", renamedBool(true), "%!d(fmt_test.renamedBool=true)"},
+ {"%o", renamedInt(8), "10"},
+ {"%d", renamedInt8(-9), "-9"},
+ {"%v", renamedInt16(10), "10"},
+ {"%v", renamedInt32(-11), "-11"},
+ {"%X", renamedInt64(255), "FF"},
+ {"%v", renamedUint(13), "13"},
+ {"%o", renamedUint8(14), "16"},
+ {"%X", renamedUint16(15), "F"},
+ {"%d", renamedUint32(16), "16"},
+ {"%X", renamedUint64(17), "11"},
+ {"%o", renamedUintptr(18), "22"},
+ {"%x", renamedString("thing"), "7468696e67"},
+ {"%d", renamedBytes([]byte{1, 2, 15}), `[1 2 15]`},
+ {"%q", renamedBytes([]byte("hello")), `"hello"`},
+ {"%x", []renamedUint8{'h', 'e', 'l', 'l', 'o'}, "68656c6c6f"},
+ {"%X", []renamedUint8{'h', 'e', 'l', 'l', 'o'}, "68656C6C6F"},
+ {"%s", []renamedUint8{'h', 'e', 'l', 'l', 'o'}, "hello"},
+ {"%q", []renamedUint8{'h', 'e', 'l', 'l', 'o'}, `"hello"`},
+ {"%v", renamedFloat32(22), "22"},
+ {"%v", renamedFloat64(33), "33"},
+ {"%v", renamedComplex64(3 + 4i), "(3+4i)"},
+ {"%v", renamedComplex128(4 - 3i), "(4-3i)"},
+
+ // Formatter
+ {"%x", F(1), ""},
+ {"%x", G(2), "2"},
+ {"%+v", S{F(4), G(5)}, "{F: G:5}"},
+
+ // GoStringer
+ {"%#v", G(6), "GoString(6)"},
+ {"%#v", S{F(7), G(8)}, "fmt_test.S{F:, G:GoString(8)}"},
+
+ // %T
+ {"%T", byte(0), "uint8"},
+ {"%T", reflect.ValueOf(nil), "reflect.Value"},
+ {"%T", (4 - 3i), "complex128"},
+ {"%T", renamedComplex128(4 - 3i), "fmt_test.renamedComplex128"},
+ {"%T", intVar, "int"},
+ {"%6T", &intVar, " *int"},
+ {"%10T", nil, " "},
+ {"%-10T", nil, " "},
+
+ // %p with pointers
+ {"%p", (*int)(nil), "0x0"},
+ {"%#p", (*int)(nil), "0"},
+ {"%p", &intVar, "0xPTR"},
+ {"%#p", &intVar, "PTR"},
+ {"%p", &array, "0xPTR"},
+ {"%p", &slice, "0xPTR"},
+ {"%8.2p", (*int)(nil), " 0x00"},
+ {"%-20.16p", &intVar, "0xPTR "},
+ // %p on non-pointers
+ {"%p", make(chan int), "0xPTR"},
+ {"%p", make(map[int]int), "0xPTR"},
+ {"%p", func() {}, "0xPTR"},
+ {"%p", 27, "%!p(int=27)"}, // not a pointer at all
+ {"%p", nil, "%!p()"}, // nil on its own has no type ...
+ {"%#p", nil, "%!p()"}, // ... and hence is not a pointer type.
+ // pointers with specified base
+ {"%b", &intVar, "PTR_b"},
+ {"%d", &intVar, "PTR_d"},
+ {"%o", &intVar, "PTR_o"},
+ {"%x", &intVar, "PTR_x"},
+ {"%X", &intVar, "PTR_X"},
+ // %v on pointers
+ {"%v", nil, ""},
+ {"%#v", nil, ""},
+ {"%v", (*int)(nil), ""},
+ {"%#v", (*int)(nil), "(*int)(nil)"},
+ {"%v", &intVar, "0xPTR"},
+ {"%#v", &intVar, "(*int)(0xPTR)"},
+ {"%8.2v", (*int)(nil), " "},
+ {"%-20.16v", &intVar, "0xPTR "},
+ // string method on pointer
+ {"%s", &pValue, "String(p)"}, // String method...
+ {"%p", &pValue, "0xPTR"}, // ... is not called with %p.
+
+ // %d on Stringer should give integer if possible
+ {"%s", time.Time{}.Month(), "January"},
+ {"%d", time.Time{}.Month(), "1"},
+
+ // erroneous things
+ {"", nil, "%!(EXTRA )"},
+ {"", 2, "%!(EXTRA int=2)"},
+ {"no args", "hello", "no args%!(EXTRA string=hello)"},
+ {"%s %", "hello", "hello %!(NOVERB)"},
+ {"%s %.2", "hello", "hello %!(NOVERB)"},
+ {"%017091901790959340919092959340919017929593813360", 0, "%!(NOVERB)%!(EXTRA int=0)"},
+ {"%184467440737095516170v", 0, "%!(NOVERB)%!(EXTRA int=0)"},
+ // Extra argument errors should format without flags set.
+ {"%010.2", "12345", "%!(NOVERB)%!(EXTRA string=12345)"},
+
+ // Test that maps with non-reflexive keys print all keys and values.
+ {"%v", map[float64]int{NaN: 1, NaN: 1}, "map[NaN:1 NaN:1]"},
+
+ // Comparison of padding rules with C printf.
+ /*
+ C program:
+ #include
+
+ char *format[] = {
+ "[%.2f]",
+ "[% .2f]",
+ "[%+.2f]",
+ "[%7.2f]",
+ "[% 7.2f]",
+ "[%+7.2f]",
+ "[% +7.2f]",
+ "[%07.2f]",
+ "[% 07.2f]",
+ "[%+07.2f]",
+ "[% +07.2f]"
+ };
+
+ int main(void) {
+ int i;
+ for(i = 0; i < 11; i++) {
+ printf("%s: ", format[i]);
+ printf(format[i], 1.0);
+ printf(" ");
+ printf(format[i], -1.0);
+ printf("\n");
+ }
+ }
+
+ Output:
+ [%.2f]: [1.00] [-1.00]
+ [% .2f]: [ 1.00] [-1.00]
+ [%+.2f]: [+1.00] [-1.00]
+ [%7.2f]: [ 1.00] [ -1.00]
+ [% 7.2f]: [ 1.00] [ -1.00]
+ [%+7.2f]: [ +1.00] [ -1.00]
+ [% +7.2f]: [ +1.00] [ -1.00]
+ [%07.2f]: [0001.00] [-001.00]
+ [% 07.2f]: [ 001.00] [-001.00]
+ [%+07.2f]: [+001.00] [-001.00]
+ [% +07.2f]: [+001.00] [-001.00]
+
+ */
+ {"%.2f", 1.0, "1.00"},
+ {"%.2f", -1.0, "-1.00"},
+ {"% .2f", 1.0, " 1.00"},
+ {"% .2f", -1.0, "-1.00"},
+ {"%+.2f", 1.0, "+1.00"},
+ {"%+.2f", -1.0, "-1.00"},
+ {"%7.2f", 1.0, " 1.00"},
+ {"%7.2f", -1.0, " -1.00"},
+ {"% 7.2f", 1.0, " 1.00"},
+ {"% 7.2f", -1.0, " -1.00"},
+ {"%+7.2f", 1.0, " +1.00"},
+ {"%+7.2f", -1.0, " -1.00"},
+ {"% +7.2f", 1.0, " +1.00"},
+ {"% +7.2f", -1.0, " -1.00"},
+ {"%07.2f", 1.0, "0001.00"},
+ {"%07.2f", -1.0, "-001.00"},
+ {"% 07.2f", 1.0, " 001.00"},
+ {"% 07.2f", -1.0, "-001.00"},
+ {"%+07.2f", 1.0, "+001.00"},
+ {"%+07.2f", -1.0, "-001.00"},
+ {"% +07.2f", 1.0, "+001.00"},
+ {"% +07.2f", -1.0, "-001.00"},
+
+ // Complex numbers: exhaustively tested in TestComplexFormatting.
+ {"%7.2f", 1 + 2i, "( 1.00 +2.00i)"},
+ {"%+07.2f", -1 - 2i, "(-001.00-002.00i)"},
+
+ // Use spaces instead of zero if padding to the right.
+ {"%0-5s", "abc", "abc "},
+ {"%-05.1f", 1.0, "1.0 "},
+
+ // float and complex formatting should not change the padding width
+ // for other elements. See issue 14642.
+ {"%06v", []any{+10.0, 10}, "[000010 000010]"},
+ {"%06v", []any{-10.0, 10}, "[-00010 000010]"},
+ {"%06v", []any{+10.0 + 10i, 10}, "[(000010+00010i) 000010]"},
+ {"%06v", []any{-10.0 + 10i, 10}, "[(-00010+00010i) 000010]"},
+
+ // integer formatting should not alter padding for other elements.
+ {"%03.6v", []any{1, 2.0, "x"}, "[000001 002 00x]"},
+ {"%03.0v", []any{0, 2.0, "x"}, "[ 002 000]"},
+
+ // Complex fmt used to leave the plus flag set for future entries in the array
+ // causing +2+0i and +3+0i instead of 2+0i and 3+0i.
+ {"%v", []complex64{1, 2, 3}, "[(1+0i) (2+0i) (3+0i)]"},
+ {"%v", []complex128{1, 2, 3}, "[(1+0i) (2+0i) (3+0i)]"},
+
+ // Incomplete format specification caused crash.
+ {"%.", 3, "%!.(int=3)"},
+
+ // Padding for complex numbers. Has been bad, then fixed, then bad again.
+ {"%+10.2f", +104.66 + 440.51i, "( +104.66 +440.51i)"},
+ {"%+10.2f", -104.66 + 440.51i, "( -104.66 +440.51i)"},
+ {"%+10.2f", +104.66 - 440.51i, "( +104.66 -440.51i)"},
+ {"%+10.2f", -104.66 - 440.51i, "( -104.66 -440.51i)"},
+ {"%+010.2f", +104.66 + 440.51i, "(+000104.66+000440.51i)"},
+ {"%+010.2f", -104.66 + 440.51i, "(-000104.66+000440.51i)"},
+ {"%+010.2f", +104.66 - 440.51i, "(+000104.66-000440.51i)"},
+ {"%+010.2f", -104.66 - 440.51i, "(-000104.66-000440.51i)"},
+
+ // []T where type T is a byte with a Stringer method.
+ {"%v", byteStringerSlice, "[X X X X X]"},
+ {"%s", byteStringerSlice, "hello"},
+ {"%q", byteStringerSlice, "\"hello\""},
+ {"%x", byteStringerSlice, "68656c6c6f"},
+ {"%X", byteStringerSlice, "68656C6C6F"},
+ {"%#v", byteStringerSlice, "[]fmt_test.byteStringer{0x68, 0x65, 0x6c, 0x6c, 0x6f}"},
+
+ // And the same for Formatter.
+ {"%v", byteFormatterSlice, "[X X X X X]"},
+ {"%s", byteFormatterSlice, "hello"},
+ {"%q", byteFormatterSlice, "\"hello\""},
+ {"%x", byteFormatterSlice, "68656c6c6f"},
+ {"%X", byteFormatterSlice, "68656C6C6F"},
+ // This next case seems wrong, but the docs say the Formatter wins here.
+ {"%#v", byteFormatterSlice, "[]fmt_test.byteFormatter{X, X, X, X, X}"},
+
+ // pp.WriteString
+ {"%s", writeStringFormatter(""), "******"},
+ {"%s", writeStringFormatter("xyz"), "***xyz***"},
+ {"%s", writeStringFormatter("⌘/⌘"), "***⌘/⌘***"},
+
+ // reflect.Value handled specially in Go 1.5, making it possible to
+ // see inside non-exported fields (which cannot be accessed with Interface()).
+ // Issue 8965.
+ {"%v", reflect.ValueOf(A{}).Field(0).String(), ""}, // Equivalent to the old way.
+ {"%v", reflect.ValueOf(A{}).Field(0), "0"}, // Sees inside the field.
+
+ // verbs apply to the extracted value too.
+ {"%s", reflect.ValueOf("hello"), "hello"},
+ {"%q", reflect.ValueOf("hello"), `"hello"`},
+ {"%#04x", reflect.ValueOf(256), "0x0100"},
+
+ // invalid reflect.Value doesn't crash.
+ {"%v", reflect.Value{}, ""},
+ {"%v", &reflect.Value{}, ""},
+ {"%v", SI{reflect.Value{}}, "{}"},
+
+ // Tests to check that not supported verbs generate an error string.
+ {"%☠", nil, "%!☠()"},
+ {"%☠", any(nil), "%!☠()"},
+ {"%☠", int(0), "%!☠(int=0)"},
+ {"%☠", uint(0), "%!☠(uint=0)"},
+ {"%☠", []byte{0, 1}, "[%!☠(uint8=0) %!☠(uint8=1)]"},
+ {"%☠", []uint8{0, 1}, "[%!☠(uint8=0) %!☠(uint8=1)]"},
+ {"%☠", [1]byte{0}, "[%!☠(uint8=0)]"},
+ {"%☠", [1]uint8{0}, "[%!☠(uint8=0)]"},
+ {"%☠", "hello", "%!☠(string=hello)"},
+ {"%☠", 1.2345678, "%!☠(float64=1.2345678)"},
+ {"%☠", float32(1.2345678), "%!☠(float32=1.2345678)"},
+ {"%☠", 1.2345678 + 1.2345678i, "%!☠(complex128=(1.2345678+1.2345678i))"},
+ {"%☠", complex64(1.2345678 + 1.2345678i), "%!☠(complex64=(1.2345678+1.2345678i))"},
+ {"%☠", &intVar, "%!☠(*int=0xPTR)"},
+ {"%☠", make(chan int), "%!☠(chan int=0xPTR)"},
+ {"%☠", func() {}, "%!☠(func()=0xPTR)"},
+ {"%☠", reflect.ValueOf(renamedInt(0)), "%!☠(fmt_test.renamedInt=0)"},
+ {"%☠", SI{renamedInt(0)}, "{%!☠(fmt_test.renamedInt=0)}"},
+ {"%☠", &[]any{I(1), G(2)}, "&[%!☠(fmt_test.I=1) %!☠(fmt_test.G=2)]"},
+ {"%☠", SI{&[]any{I(1), G(2)}}, "{%!☠(*[]interface {}=&[1 2])}"},
+ {"%☠", reflect.Value{}, ""},
+ {"%☠", map[float64]int{NaN: 1}, "map[%!☠(float64=NaN):%!☠(int=1)]"},
+}
+
+// zeroFill generates zero-filled strings of the specified width. The length
+// of the suffix (but not the prefix) is compensated for in the width calculation.
+func zeroFill(prefix string, width int, suffix string) string {
+ return prefix + strings.Repeat("0", width-len(suffix)) + suffix
+}
+
+func TestSprintf(t *testing.T) {
+ for _, tt := range fmtTests {
+ s := Sprintf(tt.fmt, tt.val)
+ i := strings.Index(tt.out, "PTR")
+ if i >= 0 && i < len(s) {
+ var pattern, chars string
+ switch {
+ case strings.HasPrefix(tt.out[i:], "PTR_b"):
+ pattern = "PTR_b"
+ chars = "01"
+ case strings.HasPrefix(tt.out[i:], "PTR_o"):
+ pattern = "PTR_o"
+ chars = "01234567"
+ case strings.HasPrefix(tt.out[i:], "PTR_d"):
+ pattern = "PTR_d"
+ chars = "0123456789"
+ case strings.HasPrefix(tt.out[i:], "PTR_x"):
+ pattern = "PTR_x"
+ chars = "0123456789abcdef"
+ case strings.HasPrefix(tt.out[i:], "PTR_X"):
+ pattern = "PTR_X"
+ chars = "0123456789ABCDEF"
+ default:
+ pattern = "PTR"
+ chars = "0123456789abcdefABCDEF"
+ }
+ p := s[:i] + pattern
+ for j := i; j < len(s); j++ {
+ if !strings.ContainsRune(chars, rune(s[j])) {
+ p += s[j:]
+ break
+ }
+ }
+ s = p
+ }
+ if s != tt.out {
+ if _, ok := tt.val.(string); ok {
+ // Don't requote the already-quoted strings.
+ // It's too confusing to read the errors.
+ t.Errorf("Sprintf(%q, %q) = <%s> want <%s>", tt.fmt, tt.val, s, tt.out)
+ } else {
+ t.Errorf("Sprintf(%q, %v) = %q want %q", tt.fmt, tt.val, s, tt.out)
+ }
+ }
+ }
+}
+
+// TestComplexFormatting checks that a complex always formats to the same
+// thing as if done by hand with two singleton prints.
+func TestComplexFormatting(t *testing.T) {
+ var yesNo = []bool{true, false}
+ var values = []float64{1, 0, -1, posInf, negInf, NaN}
+ for _, plus := range yesNo {
+ for _, zero := range yesNo {
+ for _, space := range yesNo {
+ for _, char := range "fFeEgG" {
+ realFmt := "%"
+ if zero {
+ realFmt += "0"
+ }
+ if space {
+ realFmt += " "
+ }
+ if plus {
+ realFmt += "+"
+ }
+ realFmt += "10.2"
+ realFmt += string(char)
+ // Imaginary part always has a sign, so force + and ignore space.
+ imagFmt := "%"
+ if zero {
+ imagFmt += "0"
+ }
+ imagFmt += "+"
+ imagFmt += "10.2"
+ imagFmt += string(char)
+ for _, realValue := range values {
+ for _, imagValue := range values {
+ one := Sprintf(realFmt, complex(realValue, imagValue))
+ two := Sprintf("("+realFmt+imagFmt+"i)", realValue, imagValue)
+ if one != two {
+ t.Error(f, one, two)
+ }
+ }
+ }
+ }
+ }
+ }
+ }
+}
+
+type SE []any // slice of empty; notational compactness.
+
+var reorderTests = []struct {
+ fmt string
+ val SE
+ out string
+}{
+ {"%[1]d", SE{1}, "1"},
+ {"%[2]d", SE{2, 1}, "1"},
+ {"%[2]d %[1]d", SE{1, 2}, "2 1"},
+ {"%[2]*[1]d", SE{2, 5}, " 2"},
+ {"%6.2f", SE{12.0}, " 12.00"}, // Explicit version of next line.
+ {"%[3]*.[2]*[1]f", SE{12.0, 2, 6}, " 12.00"},
+ {"%[1]*.[2]*[3]f", SE{6, 2, 12.0}, " 12.00"},
+ {"%10f", SE{12.0}, " 12.000000"},
+ {"%[1]*[3]f", SE{10, 99, 12.0}, " 12.000000"},
+ {"%.6f", SE{12.0}, "12.000000"}, // Explicit version of next line.
+ {"%.[1]*[3]f", SE{6, 99, 12.0}, "12.000000"},
+ {"%6.f", SE{12.0}, " 12"}, // // Explicit version of next line; empty precision means zero.
+ {"%[1]*.[3]f", SE{6, 3, 12.0}, " 12"},
+ // An actual use! Print the same arguments twice.
+ {"%d %d %d %#[1]o %#o %#o", SE{11, 12, 13}, "11 12 13 013 014 015"},
+
+ // Erroneous cases.
+ {"%[d", SE{2, 1}, "%!d(BADINDEX)"},
+ {"%]d", SE{2, 1}, "%!](int=2)d%!(EXTRA int=1)"},
+ {"%[]d", SE{2, 1}, "%!d(BADINDEX)"},
+ {"%[-3]d", SE{2, 1}, "%!d(BADINDEX)"},
+ {"%[99]d", SE{2, 1}, "%!d(BADINDEX)"},
+ {"%[3]", SE{2, 1}, "%!(NOVERB)"},
+ {"%[1].2d", SE{5, 6}, "%!d(BADINDEX)"},
+ {"%[1]2d", SE{2, 1}, "%!d(BADINDEX)"},
+ {"%3.[2]d", SE{7}, "%!d(BADINDEX)"},
+ {"%.[2]d", SE{7}, "%!d(BADINDEX)"},
+ {"%d %d %d %#[1]o %#o %#o %#o", SE{11, 12, 13}, "11 12 13 013 014 015 %!o(MISSING)"},
+ {"%[5]d %[2]d %d", SE{1, 2, 3}, "%!d(BADINDEX) 2 3"},
+ {"%d %[3]d %d", SE{1, 2}, "1 %!d(BADINDEX) 2"}, // Erroneous index does not affect sequence.
+ {"%.[]", SE{}, "%!](BADINDEX)"}, // Issue 10675
+ {"%.-3d", SE{42}, "%!-(int=42)3d"}, // TODO: Should this set return better error messages?
+ {"%2147483648d", SE{42}, "%!(NOVERB)%!(EXTRA int=42)"},
+ {"%-2147483648d", SE{42}, "%!(NOVERB)%!(EXTRA int=42)"},
+ {"%.2147483648d", SE{42}, "%!(NOVERB)%!(EXTRA int=42)"},
+}
+
+func TestReorder(t *testing.T) {
+ for _, tt := range reorderTests {
+ s := Sprintf(tt.fmt, tt.val...)
+ if s != tt.out {
+ t.Errorf("Sprintf(%q, %v) = <%s> want <%s>", tt.fmt, tt.val, s, tt.out)
+ }
+ }
+}
+
+func BenchmarkSprintfPadding(b *testing.B) {
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ _ = Sprintf("%16f", 1.0)
+ }
+ })
+}
+
+func BenchmarkSprintfEmpty(b *testing.B) {
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ _ = Sprintf("")
+ }
+ })
+}
+
+func BenchmarkSprintfString(b *testing.B) {
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ _ = Sprintf("%s", "hello")
+ }
+ })
+}
+
+func BenchmarkSprintfTruncateString(b *testing.B) {
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ _ = Sprintf("%.3s", "日本語日本語日本語日本語")
+ }
+ })
+}
+
+func BenchmarkSprintfTruncateBytes(b *testing.B) {
+ var bytes any = []byte("日本語日本語日本語日本語")
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ _ = Sprintf("%.3s", bytes)
+ }
+ })
+}
+
+func BenchmarkSprintfSlowParsingPath(b *testing.B) {
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ _ = Sprintf("%.v", nil)
+ }
+ })
+}
+
+func BenchmarkSprintfQuoteString(b *testing.B) {
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ _ = Sprintf("%q", "日本語日本語日本語")
+ }
+ })
+}
+
+func BenchmarkSprintfInt(b *testing.B) {
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ _ = Sprintf("%d", 5)
+ }
+ })
+}
+
+func BenchmarkSprintfIntInt(b *testing.B) {
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ _ = Sprintf("%d %d", 5, 6)
+ }
+ })
+}
+
+func BenchmarkSprintfPrefixedInt(b *testing.B) {
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ _ = Sprintf("This is some meaningless prefix text that needs to be scanned %d", 6)
+ }
+ })
+}
+
+func BenchmarkSprintfFloat(b *testing.B) {
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ _ = Sprintf("%g", 5.23184)
+ }
+ })
+}
+
+func BenchmarkSprintfComplex(b *testing.B) {
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ _ = Sprintf("%f", 5.23184+5.23184i)
+ }
+ })
+}
+
+func BenchmarkSprintfBoolean(b *testing.B) {
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ _ = Sprintf("%t", true)
+ }
+ })
+}
+
+func BenchmarkSprintfHexString(b *testing.B) {
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ _ = Sprintf("% #x", "0123456789abcdef")
+ }
+ })
+}
+
+func BenchmarkSprintfHexBytes(b *testing.B) {
+ data := []byte("0123456789abcdef")
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ _ = Sprintf("% #x", data)
+ }
+ })
+}
+
+func BenchmarkSprintfBytes(b *testing.B) {
+ data := []byte("0123456789abcdef")
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ _ = Sprintf("%v", data)
+ }
+ })
+}
+
+func BenchmarkSprintfStringer(b *testing.B) {
+ stringer := I(12345)
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ _ = Sprintf("%v", stringer)
+ }
+ })
+}
+
+func BenchmarkSprintfStructure(b *testing.B) {
+ s := &[]any{SI{12345}, map[int]string{0: "hello"}}
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ _ = Sprintf("%#v", s)
+ }
+ })
+}
+
+func BenchmarkManyArgs(b *testing.B) {
+ b.RunParallel(func(pb *testing.PB) {
+ var buf bytes.Buffer
+ for pb.Next() {
+ buf.Reset()
+ Fprintf(&buf, "%2d/%2d/%2d %d:%d:%d %s %s\n", 3, 4, 5, 11, 12, 13, "hello", "world")
+ }
+ })
+}
+
+func BenchmarkFprintInt(b *testing.B) {
+ var buf bytes.Buffer
+ for i := 0; i < b.N; i++ {
+ buf.Reset()
+ Fprint(&buf, 123456)
+ }
+}
+
+func BenchmarkFprintfBytes(b *testing.B) {
+ data := []byte(string("0123456789"))
+ var buf bytes.Buffer
+ for i := 0; i < b.N; i++ {
+ buf.Reset()
+ Fprintf(&buf, "%s", data)
+ }
+}
+
+func BenchmarkFprintIntNoAlloc(b *testing.B) {
+ var x any = 123456
+ var buf bytes.Buffer
+ for i := 0; i < b.N; i++ {
+ buf.Reset()
+ Fprint(&buf, x)
+ }
+}
+
+var mallocBuf bytes.Buffer
+var mallocPointer *int // A pointer so we know the interface value won't allocate.
+var sink any
+
+var mallocTest = []struct {
+ count int
+ desc string
+ fn func()
+}{
+ {0, `Sprintf("")`, func() { _ = Sprintf("") }},
+ {1, `Sprintf("xxx")`, func() { _ = Sprintf("xxx") }},
+ {0, `Sprintf("%x")`, func() { _ = Sprintf("%x", 7) }},
+ {1, `Sprintf("%x")`, func() { _ = Sprintf("%x", 1<<16) }},
+ {3, `Sprintf("%80000s")`, func() { _ = Sprintf("%80000s", "hello") }}, // large buffer (>64KB)
+ {1, `Sprintf("%s")`, func() { _ = Sprintf("%s", "hello") }},
+ {1, `Sprintf("%x %x")`, func() { _ = Sprintf("%x %x", 7, 112) }},
+ {1, `Sprintf("%g")`, func() { _ = Sprintf("%g", float32(3.14159)) }},
+ {0, `Fprintf(buf, "%s")`, func() { mallocBuf.Reset(); Fprintf(&mallocBuf, "%s", "hello") }},
+ {0, `Fprintf(buf, "%s")`, func() { mallocBuf.Reset(); s := "hello"; Fprintf(&mallocBuf, "%s", s) }},
+ {1, `Fprintf(buf, "%s")`, func() { mallocBuf.Reset(); s := "hello"; Fprintf(&mallocBuf, "%s", noliteral(s)) }},
+ {0, `Fprintf(buf, "%x")`, func() { mallocBuf.Reset(); Fprintf(&mallocBuf, "%x", 7) }},
+ {0, `Fprintf(buf, "%x")`, func() { mallocBuf.Reset(); Fprintf(&mallocBuf, "%x", 1<<16) }},
+ {0, `Fprintf(buf, "%x")`, func() { mallocBuf.Reset(); i := 1 << 16; Fprintf(&mallocBuf, "%x", i) }},
+ {1, `Fprintf(buf, "%x")`, func() { mallocBuf.Reset(); i := 1 << 16; Fprintf(&mallocBuf, "%x", noliteral(i)) }},
+ {4, `Fprintf(buf, "%v")`, func() { mallocBuf.Reset(); s := []int{1, 2}; Fprintf(&mallocBuf, "%v", s) }},
+ {0, `Fprintf(buf, "%v")`, func() { mallocBuf.Reset(); type P struct{ x, y int }; Fprintf(&mallocBuf, "%v", P{1, 2}) }},
+ {1, `Fprintf(buf, "%v")`, func() { mallocBuf.Reset(); type P struct{ x, y int }; Fprintf(&mallocBuf, "%v", noliteral(P{1, 2})) }},
+ {2, `Fprintf(buf, "%80000s")`, func() { mallocBuf.Reset(); Fprintf(&mallocBuf, "%80000s", "hello") }}, // large buffer (>64KB)
+ // If the interface value doesn't need to allocate, amortized allocation overhead should be zero.
+ {0, `Fprintf(buf, "%x %x %x")`, func() {
+ mallocBuf.Reset()
+ Fprintf(&mallocBuf, "%x %x %x", mallocPointer, mallocPointer, mallocPointer)
+ }},
+ {0, `Errorf("hello")`, func() { _ = Errorf("hello") }},
+ {2, `Errorf("hello: %x")`, func() { _ = Errorf("hello: %x", mallocPointer) }},
+ {1, `sink = Errorf("hello")`, func() { sink = Errorf("hello") }},
+ {2, `sink = Errorf("hello: %x")`, func() { sink = Errorf("hello: %x", mallocPointer) }},
+}
+
+var _ bytes.Buffer
+
+func TestCountMallocs(t *testing.T) {
+ switch {
+ case testing.Short():
+ t.Skip("skipping malloc count in short mode")
+ case race.Enabled:
+ t.Skip("skipping malloc count under race detector")
+ }
+ for _, mt := range mallocTest {
+ mallocs := testing.AllocsPerRun(100, mt.fn)
+ if got, max := mallocs, float64(mt.count); got != max {
+ t.Errorf("%s: got %v allocs, want %v", mt.desc, got, max)
+ }
+ }
+}
+
+type flagPrinter struct{}
+
+func (flagPrinter) Format(f State, c rune) {
+ s := "%"
+ for i := 0; i < 128; i++ {
+ if f.Flag(i) {
+ s += string(rune(i))
+ }
+ }
+ if w, ok := f.Width(); ok {
+ s += Sprintf("%d", w)
+ }
+ if p, ok := f.Precision(); ok {
+ s += Sprintf(".%d", p)
+ }
+ s += string(c)
+ io.WriteString(f, "["+s+"]")
+}
+
+var flagtests = []struct {
+ in string
+ out string
+}{
+ {"%a", "[%a]"},
+ {"%-a", "[%-a]"},
+ {"%+a", "[%+a]"},
+ {"%#a", "[%#a]"},
+ {"% a", "[% a]"},
+ {"%0a", "[%0a]"},
+ {"%1.2a", "[%1.2a]"},
+ {"%-1.2a", "[%-1.2a]"},
+ {"%+1.2a", "[%+1.2a]"},
+ {"%-+1.2a", "[%+-1.2a]"},
+ {"%-+1.2abc", "[%+-1.2a]bc"},
+ {"%-1.2abc", "[%-1.2a]bc"},
+ {"%-0abc", "[%-0a]bc"},
+}
+
+func TestFlagParser(t *testing.T) {
+ var flagprinter flagPrinter
+ for _, tt := range flagtests {
+ s := Sprintf(tt.in, &flagprinter)
+ if s != tt.out {
+ t.Errorf("Sprintf(%q, &flagprinter) => %q, want %q", tt.in, s, tt.out)
+ }
+ }
+}
+
+func TestStructPrinter(t *testing.T) {
+ type T struct {
+ a string
+ b string
+ c int
+ }
+ var s T
+ s.a = "abc"
+ s.b = "def"
+ s.c = 123
+ var tests = []struct {
+ fmt string
+ out string
+ }{
+ {"%v", "{abc def 123}"},
+ {"%+v", "{a:abc b:def c:123}"},
+ {"%#v", `fmt_test.T{a:"abc", b:"def", c:123}`},
+ }
+ for _, tt := range tests {
+ out := Sprintf(tt.fmt, s)
+ if out != tt.out {
+ t.Errorf("Sprintf(%q, s) = %#q, want %#q", tt.fmt, out, tt.out)
+ }
+ // The same but with a pointer.
+ out = Sprintf(tt.fmt, &s)
+ if out != "&"+tt.out {
+ t.Errorf("Sprintf(%q, &s) = %#q, want %#q", tt.fmt, out, "&"+tt.out)
+ }
+ }
+}
+
+func TestSlicePrinter(t *testing.T) {
+ slice := []int{}
+ s := Sprint(slice)
+ if s != "[]" {
+ t.Errorf("empty slice printed as %q not %q", s, "[]")
+ }
+ slice = []int{1, 2, 3}
+ s = Sprint(slice)
+ if s != "[1 2 3]" {
+ t.Errorf("slice: got %q expected %q", s, "[1 2 3]")
+ }
+ s = Sprint(&slice)
+ if s != "&[1 2 3]" {
+ t.Errorf("&slice: got %q expected %q", s, "&[1 2 3]")
+ }
+}
+
+// presentInMap checks map printing using substrings so we don't depend on the
+// print order.
+func presentInMap(s string, a []string, t *testing.T) {
+ for i := 0; i < len(a); i++ {
+ loc := strings.Index(s, a[i])
+ if loc < 0 {
+ t.Errorf("map print: expected to find %q in %q", a[i], s)
+ }
+ // make sure the match ends here
+ loc += len(a[i])
+ if loc >= len(s) || (s[loc] != ' ' && s[loc] != ']') {
+ t.Errorf("map print: %q not properly terminated in %q", a[i], s)
+ }
+ }
+}
+
+func TestMapPrinter(t *testing.T) {
+ m0 := make(map[int]string)
+ s := Sprint(m0)
+ if s != "map[]" {
+ t.Errorf("empty map printed as %q not %q", s, "map[]")
+ }
+ m1 := map[int]string{1: "one", 2: "two", 3: "three"}
+ a := []string{"1:one", "2:two", "3:three"}
+ presentInMap(Sprintf("%v", m1), a, t)
+ presentInMap(Sprint(m1), a, t)
+ // Pointer to map prints the same but with initial &.
+ if !strings.HasPrefix(Sprint(&m1), "&") {
+ t.Errorf("no initial & for address of map")
+ }
+ presentInMap(Sprintf("%v", &m1), a, t)
+ presentInMap(Sprint(&m1), a, t)
+}
+
+func TestEmptyMap(t *testing.T) {
+ const emptyMapStr = "map[]"
+ var m map[string]int
+ s := Sprint(m)
+ if s != emptyMapStr {
+ t.Errorf("nil map printed as %q not %q", s, emptyMapStr)
+ }
+ m = make(map[string]int)
+ s = Sprint(m)
+ if s != emptyMapStr {
+ t.Errorf("empty map printed as %q not %q", s, emptyMapStr)
+ }
+}
+
+// TestBlank checks that Sprint (and hence Print, Fprint) puts spaces in the
+// right places, that is, between arg pairs in which neither is a string.
+func TestBlank(t *testing.T) {
+ got := Sprint("<", 1, ">:", 1, 2, 3, "!")
+ expect := "<1>:1 2 3!"
+ if got != expect {
+ t.Errorf("got %q expected %q", got, expect)
+ }
+}
+
+// TestBlankln checks that Sprintln (and hence Println, Fprintln) puts spaces in
+// the right places, that is, between all arg pairs.
+func TestBlankln(t *testing.T) {
+ got := Sprintln("<", 1, ">:", 1, 2, 3, "!")
+ expect := "< 1 >: 1 2 3 !\n"
+ if got != expect {
+ t.Errorf("got %q expected %q", got, expect)
+ }
+}
+
+// TestFormatterPrintln checks Formatter with Sprint, Sprintln, Sprintf.
+func TestFormatterPrintln(t *testing.T) {
+ f := F(1)
+ expect := "\n"
+ s := Sprint(f, "\n")
+ if s != expect {
+ t.Errorf("Sprint wrong with Formatter: expected %q got %q", expect, s)
+ }
+ s = Sprintln(f)
+ if s != expect {
+ t.Errorf("Sprintln wrong with Formatter: expected %q got %q", expect, s)
+ }
+ s = Sprintf("%v\n", f)
+ if s != expect {
+ t.Errorf("Sprintf wrong with Formatter: expected %q got %q", expect, s)
+ }
+}
+
+func args(a ...any) []any { return a }
+
+var startests = []struct {
+ fmt string
+ in []any
+ out string
+}{
+ {"%*d", args(4, 42), " 42"},
+ {"%-*d", args(4, 42), "42 "},
+ {"%*d", args(-4, 42), "42 "},
+ {"%-*d", args(-4, 42), "42 "},
+ {"%.*d", args(4, 42), "0042"},
+ {"%*.*d", args(8, 4, 42), " 0042"},
+ {"%0*d", args(4, 42), "0042"},
+ // Some non-int types for width. (Issue 10732).
+ {"%0*d", args(uint(4), 42), "0042"},
+ {"%0*d", args(uint64(4), 42), "0042"},
+ {"%0*d", args('\x04', 42), "0042"},
+ {"%0*d", args(uintptr(4), 42), "0042"},
+
+ // erroneous
+ {"%*d", args(nil, 42), "%!(BADWIDTH)42"},
+ {"%*d", args(int(1e7), 42), "%!(BADWIDTH)42"},
+ {"%*d", args(int(-1e7), 42), "%!(BADWIDTH)42"},
+ {"%.*d", args(nil, 42), "%!(BADPREC)42"},
+ {"%.*d", args(-1, 42), "%!(BADPREC)42"},
+ {"%.*d", args(int(1e7), 42), "%!(BADPREC)42"},
+ {"%.*d", args(uint(1e7), 42), "%!(BADPREC)42"},
+ {"%.*d", args(uint64(1<<63), 42), "%!(BADPREC)42"}, // Huge negative (-inf).
+ {"%.*d", args(uint64(1<<64-1), 42), "%!(BADPREC)42"}, // Small negative (-1).
+ {"%*d", args(5, "foo"), "%!d(string= foo)"},
+ {"%*% %d", args(20, 5), "% 5"},
+ {"%*", args(4), "%!(NOVERB)"},
+}
+
+func TestWidthAndPrecision(t *testing.T) {
+ for i, tt := range startests {
+ s := Sprintf(tt.fmt, tt.in...)
+ if s != tt.out {
+ t.Errorf("#%d: %q: got %q expected %q", i, tt.fmt, s, tt.out)
+ }
+ }
+}
+
+// PanicS is a type that panics in String.
+type PanicS struct {
+ message any
+}
+
+// Value receiver.
+func (p PanicS) String() string {
+ panic(p.message)
+}
+
+// PanicGo is a type that panics in GoString.
+type PanicGo struct {
+ message any
+}
+
+// Value receiver.
+func (p PanicGo) GoString() string {
+ panic(p.message)
+}
+
+// PanicF is a type that panics in Format.
+type PanicF struct {
+ message any
+}
+
+// Value receiver.
+func (p PanicF) Format(f State, c rune) {
+ panic(p.message)
+}
+
+var panictests = []struct {
+ fmt string
+ in any
+ out string
+}{
+ // String
+ {"%s", (*PanicS)(nil), ""}, // nil pointer special case
+ {"%s", PanicS{io.ErrUnexpectedEOF}, "%!s(PANIC=String method: unexpected EOF)"},
+ {"%s", PanicS{3}, "%!s(PANIC=String method: 3)"},
+ // GoString
+ {"%#v", (*PanicGo)(nil), ""}, // nil pointer special case
+ {"%#v", PanicGo{io.ErrUnexpectedEOF}, "%!v(PANIC=GoString method: unexpected EOF)"},
+ {"%#v", PanicGo{3}, "%!v(PANIC=GoString method: 3)"},
+ // Issue 18282. catchPanic should not clear fmtFlags permanently.
+ {"%#v", []any{PanicGo{3}, PanicGo{3}}, "[]interface {}{%!v(PANIC=GoString method: 3), %!v(PANIC=GoString method: 3)}"},
+ // Format
+ {"%s", (*PanicF)(nil), ""}, // nil pointer special case
+ {"%s", PanicF{io.ErrUnexpectedEOF}, "%!s(PANIC=Format method: unexpected EOF)"},
+ {"%s", PanicF{3}, "%!s(PANIC=Format method: 3)"},
+}
+
+func TestPanics(t *testing.T) {
+ for i, tt := range panictests {
+ s := Sprintf(tt.fmt, tt.in)
+ if s != tt.out {
+ t.Errorf("%d: %q: got %q expected %q", i, tt.fmt, s, tt.out)
+ }
+ }
+}
+
+// recurCount tests that erroneous String routine doesn't cause fatal recursion.
+var recurCount = 0
+
+type Recur struct {
+ i int
+ failed *bool
+}
+
+func (r *Recur) String() string {
+ if recurCount++; recurCount > 10 {
+ *r.failed = true
+ return "FAIL"
+ }
+ // This will call badVerb. Before the fix, that would cause us to recur into
+ // this routine to print %!p(value). Now we don't call the user's method
+ // during an error.
+ return Sprintf("recur@%p value: %d", r, r.i)
+}
+
+func TestBadVerbRecursion(t *testing.T) {
+ failed := false
+ r := &Recur{3, &failed}
+ _ = Sprintf("recur@%p value: %d\n", &r, r.i)
+ if failed {
+ t.Error("fail with pointer")
+ }
+ failed = false
+ r = &Recur{4, &failed}
+ _ = Sprintf("recur@%p, value: %d\n", r, r.i)
+ if failed {
+ t.Error("fail with value")
+ }
+}
+
+func TestIsSpace(t *testing.T) {
+ // This tests the internal isSpace function.
+ // IsSpace = isSpace is defined in export_test.go.
+ for i := rune(0); i <= unicode.MaxRune; i++ {
+ if IsSpace(i) != unicode.IsSpace(i) {
+ t.Errorf("isSpace(%U) = %v, want %v", i, IsSpace(i), unicode.IsSpace(i))
+ }
+ }
+}
+
+func hideFromVet(s string) string { return s }
+
+func TestNilDoesNotBecomeTyped(t *testing.T) {
+ type A struct{}
+ type B struct{}
+ var a *A = nil
+ var b B = B{}
+ got := Sprintf(hideFromVet("%s %s %s %s %s"), nil, a, nil, b, nil)
+ const expect = "%!s() %!s(*fmt_test.A=) %!s() {} %!s()"
+ if got != expect {
+ t.Errorf("expected:\n\t%q\ngot:\n\t%q", expect, got)
+ }
+}
+
+var formatterFlagTests = []struct {
+ in string
+ val any
+ out string
+}{
+ // scalar values with the (unused by fmt) 'a' verb.
+ {"%a", flagPrinter{}, "[%a]"},
+ {"%-a", flagPrinter{}, "[%-a]"},
+ {"%+a", flagPrinter{}, "[%+a]"},
+ {"%#a", flagPrinter{}, "[%#a]"},
+ {"% a", flagPrinter{}, "[% a]"},
+ {"%0a", flagPrinter{}, "[%0a]"},
+ {"%1.2a", flagPrinter{}, "[%1.2a]"},
+ {"%-1.2a", flagPrinter{}, "[%-1.2a]"},
+ {"%+1.2a", flagPrinter{}, "[%+1.2a]"},
+ {"%-+1.2a", flagPrinter{}, "[%+-1.2a]"},
+ {"%-+1.2abc", flagPrinter{}, "[%+-1.2a]bc"},
+ {"%-1.2abc", flagPrinter{}, "[%-1.2a]bc"},
+ {"%-0abc", flagPrinter{}, "[%-0a]bc"},
+
+ // composite values with the 'a' verb
+ {"%a", [1]flagPrinter{}, "[[%a]]"},
+ {"%-a", [1]flagPrinter{}, "[[%-a]]"},
+ {"%+a", [1]flagPrinter{}, "[[%+a]]"},
+ {"%#a", [1]flagPrinter{}, "[[%#a]]"},
+ {"% a", [1]flagPrinter{}, "[[% a]]"},
+ {"%0a", [1]flagPrinter{}, "[[%0a]]"},
+ {"%1.2a", [1]flagPrinter{}, "[[%1.2a]]"},
+ {"%-1.2a", [1]flagPrinter{}, "[[%-1.2a]]"},
+ {"%+1.2a", [1]flagPrinter{}, "[[%+1.2a]]"},
+ {"%-+1.2a", [1]flagPrinter{}, "[[%+-1.2a]]"},
+ {"%-+1.2abc", [1]flagPrinter{}, "[[%+-1.2a]]bc"},
+ {"%-1.2abc", [1]flagPrinter{}, "[[%-1.2a]]bc"},
+ {"%-0abc", [1]flagPrinter{}, "[[%-0a]]bc"},
+
+ // simple values with the 'v' verb
+ {"%v", flagPrinter{}, "[%v]"},
+ {"%-v", flagPrinter{}, "[%-v]"},
+ {"%+v", flagPrinter{}, "[%+v]"},
+ {"%#v", flagPrinter{}, "[%#v]"},
+ {"% v", flagPrinter{}, "[% v]"},
+ {"%0v", flagPrinter{}, "[%0v]"},
+ {"%1.2v", flagPrinter{}, "[%1.2v]"},
+ {"%-1.2v", flagPrinter{}, "[%-1.2v]"},
+ {"%+1.2v", flagPrinter{}, "[%+1.2v]"},
+ {"%-+1.2v", flagPrinter{}, "[%+-1.2v]"},
+ {"%-+1.2vbc", flagPrinter{}, "[%+-1.2v]bc"},
+ {"%-1.2vbc", flagPrinter{}, "[%-1.2v]bc"},
+ {"%-0vbc", flagPrinter{}, "[%-0v]bc"},
+
+ // composite values with the 'v' verb.
+ {"%v", [1]flagPrinter{}, "[[%v]]"},
+ {"%-v", [1]flagPrinter{}, "[[%-v]]"},
+ {"%+v", [1]flagPrinter{}, "[[%+v]]"},
+ {"%#v", [1]flagPrinter{}, "[1]fmt_test.flagPrinter{[%#v]}"},
+ {"% v", [1]flagPrinter{}, "[[% v]]"},
+ {"%0v", [1]flagPrinter{}, "[[%0v]]"},
+ {"%1.2v", [1]flagPrinter{}, "[[%1.2v]]"},
+ {"%-1.2v", [1]flagPrinter{}, "[[%-1.2v]]"},
+ {"%+1.2v", [1]flagPrinter{}, "[[%+1.2v]]"},
+ {"%-+1.2v", [1]flagPrinter{}, "[[%+-1.2v]]"},
+ {"%-+1.2vbc", [1]flagPrinter{}, "[[%+-1.2v]]bc"},
+ {"%-1.2vbc", [1]flagPrinter{}, "[[%-1.2v]]bc"},
+ {"%-0vbc", [1]flagPrinter{}, "[[%-0v]]bc"},
+}
+
+func TestFormatterFlags(t *testing.T) {
+ for _, tt := range formatterFlagTests {
+ s := Sprintf(tt.in, tt.val)
+ if s != tt.out {
+ t.Errorf("Sprintf(%q, %T) = %q, want %q", tt.in, tt.val, s, tt.out)
+ }
+ }
+}
+
+func TestParsenum(t *testing.T) {
+ testCases := []struct {
+ s string
+ start, end int
+ num int
+ isnum bool
+ newi int
+ }{
+ {"a123", 0, 4, 0, false, 0},
+ {"1234", 1, 1, 0, false, 1},
+ {"123a", 0, 4, 123, true, 3},
+ {"12a3", 0, 4, 12, true, 2},
+ {"1234", 0, 4, 1234, true, 4},
+ {"1a234", 1, 3, 0, false, 1},
+ }
+ for _, tt := range testCases {
+ num, isnum, newi := Parsenum(tt.s, tt.start, tt.end)
+ if num != tt.num || isnum != tt.isnum || newi != tt.newi {
+ t.Errorf("parsenum(%q, %d, %d) = %d, %v, %d, want %d, %v, %d", tt.s, tt.start, tt.end, num, isnum, newi, tt.num, tt.isnum, tt.newi)
+ }
+ }
+}
+
+// Test the various Append printers. The details are well tested above;
+// here we just make sure the byte slice is updated.
+
+const (
+ appendResult = "hello world, 23"
+ hello = "hello "
+)
+
+func TestAppendf(t *testing.T) {
+ b := make([]byte, 100)
+ b = b[:copy(b, hello)]
+ got := Appendf(b, "world, %d", 23)
+ if string(got) != appendResult {
+ t.Fatalf("Appendf returns %q not %q", got, appendResult)
+ }
+ if &b[0] != &got[0] {
+ t.Fatalf("Appendf allocated a new slice")
+ }
+}
+
+func TestAppend(t *testing.T) {
+ b := make([]byte, 100)
+ b = b[:copy(b, hello)]
+ got := Append(b, "world", ", ", 23)
+ if string(got) != appendResult {
+ t.Fatalf("Append returns %q not %q", got, appendResult)
+ }
+ if &b[0] != &got[0] {
+ t.Fatalf("Append allocated a new slice")
+ }
+}
+
+func TestAppendln(t *testing.T) {
+ b := make([]byte, 100)
+ b = b[:copy(b, hello)]
+ got := Appendln(b, "world,", 23)
+ if string(got) != appendResult+"\n" {
+ t.Fatalf("Appendln returns %q not %q", got, appendResult+"\n")
+ }
+ if &b[0] != &got[0] {
+ t.Fatalf("Appendln allocated a new slice")
+ }
+}
+
+// noliteral prevents escape analysis from recognizing a literal value.
+//
+//go:noinline
+func noliteral[T any](t T) T {
+ return t
+}
diff --git a/go/src/fmt/format.go b/go/src/fmt/format.go
new file mode 100644
index 0000000000000000000000000000000000000000..334a94e2983e634a0d010742e93dc39d30fa6b9d
--- /dev/null
+++ b/go/src/fmt/format.go
@@ -0,0 +1,595 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package fmt
+
+import (
+ "strconv"
+ "unicode/utf8"
+)
+
+const (
+ ldigits = "0123456789abcdefx"
+ udigits = "0123456789ABCDEFX"
+)
+
+const (
+ signed = true
+ unsigned = false
+)
+
+// flags placed in a separate struct for easy clearing.
+type fmtFlags struct {
+ widPresent bool
+ precPresent bool
+ minus bool
+ plus bool
+ sharp bool
+ space bool
+ zero bool
+
+ // For the formats %+v %#v, we set the plusV/sharpV flags
+ // and clear the plus/sharp flags since %+v and %#v are in effect
+ // different, flagless formats set at the top level.
+ plusV bool
+ sharpV bool
+}
+
+// A fmt is the raw formatter used by Printf etc.
+// It prints into a buffer that must be set up separately.
+type fmt struct {
+ buf *buffer
+
+ fmtFlags
+
+ wid int // width
+ prec int // precision
+
+ // intbuf is large enough to store %b of an int64 with a sign and
+ // avoids padding at the end of the struct on 32 bit architectures.
+ intbuf [68]byte
+}
+
+func (f *fmt) clearflags() {
+ f.fmtFlags = fmtFlags{}
+ f.wid = 0
+ f.prec = 0
+}
+
+func (f *fmt) init(buf *buffer) {
+ f.buf = buf
+ f.clearflags()
+}
+
+// writePadding generates n bytes of padding.
+func (f *fmt) writePadding(n int) {
+ if n <= 0 { // No padding bytes needed.
+ return
+ }
+ buf := *f.buf
+ oldLen := len(buf)
+ newLen := oldLen + n
+ // Make enough room for padding.
+ if newLen > cap(buf) {
+ buf = make(buffer, cap(buf)*2+n)
+ copy(buf, *f.buf)
+ }
+ // Decide which byte the padding should be filled with.
+ padByte := byte(' ')
+ // Zero padding is allowed only to the left.
+ if f.zero && !f.minus {
+ padByte = byte('0')
+ }
+ // Fill padding with padByte.
+ padding := buf[oldLen:newLen]
+ for i := range padding {
+ padding[i] = padByte
+ }
+ *f.buf = buf[:newLen]
+}
+
+// pad appends b to f.buf, padded on left (!f.minus) or right (f.minus).
+func (f *fmt) pad(b []byte) {
+ if !f.widPresent || f.wid == 0 {
+ f.buf.write(b)
+ return
+ }
+ width := f.wid - utf8.RuneCount(b)
+ if !f.minus {
+ // left padding
+ f.writePadding(width)
+ f.buf.write(b)
+ } else {
+ // right padding
+ f.buf.write(b)
+ f.writePadding(width)
+ }
+}
+
+// padString appends s to f.buf, padded on left (!f.minus) or right (f.minus).
+func (f *fmt) padString(s string) {
+ if !f.widPresent || f.wid == 0 {
+ f.buf.writeString(s)
+ return
+ }
+ width := f.wid - utf8.RuneCountInString(s)
+ if !f.minus {
+ // left padding
+ f.writePadding(width)
+ f.buf.writeString(s)
+ } else {
+ // right padding
+ f.buf.writeString(s)
+ f.writePadding(width)
+ }
+}
+
+// fmtBoolean formats a boolean.
+func (f *fmt) fmtBoolean(v bool) {
+ if v {
+ f.padString("true")
+ } else {
+ f.padString("false")
+ }
+}
+
+// fmtUnicode formats a uint64 as "U+0078" or with f.sharp set as "U+0078 'x'".
+func (f *fmt) fmtUnicode(u uint64) {
+ buf := f.intbuf[0:]
+
+ // With default precision set the maximum needed buf length is 18
+ // for formatting -1 with %#U ("U+FFFFFFFFFFFFFFFF") which fits
+ // into the already allocated intbuf with a capacity of 68 bytes.
+ prec := 4
+ if f.precPresent && f.prec > 4 {
+ prec = f.prec
+ // Compute space needed for "U+" , number, " '", character, "'".
+ width := 2 + prec + 2 + utf8.UTFMax + 1
+ if width > len(buf) {
+ buf = make([]byte, width)
+ }
+ }
+
+ // Format into buf, ending at buf[i]. Formatting numbers is easier right-to-left.
+ i := len(buf)
+
+ // For %#U we want to add a space and a quoted character at the end of the buffer.
+ if f.sharp && u <= utf8.MaxRune && strconv.IsPrint(rune(u)) {
+ i--
+ buf[i] = '\''
+ i -= utf8.RuneLen(rune(u))
+ utf8.EncodeRune(buf[i:], rune(u))
+ i--
+ buf[i] = '\''
+ i--
+ buf[i] = ' '
+ }
+ // Format the Unicode code point u as a hexadecimal number.
+ for u >= 16 {
+ i--
+ buf[i] = udigits[u&0xF]
+ prec--
+ u >>= 4
+ }
+ i--
+ buf[i] = udigits[u]
+ prec--
+ // Add zeros in front of the number until requested precision is reached.
+ for prec > 0 {
+ i--
+ buf[i] = '0'
+ prec--
+ }
+ // Add a leading "U+".
+ i--
+ buf[i] = '+'
+ i--
+ buf[i] = 'U'
+
+ oldZero := f.zero
+ f.zero = false
+ f.pad(buf[i:])
+ f.zero = oldZero
+}
+
+// fmtInteger formats signed and unsigned integers.
+func (f *fmt) fmtInteger(u uint64, base int, isSigned bool, verb rune, digits string) {
+ negative := isSigned && int64(u) < 0
+ if negative {
+ u = -u
+ }
+
+ buf := f.intbuf[0:]
+ // The already allocated f.intbuf with a capacity of 68 bytes
+ // is large enough for integer formatting when no precision or width is set.
+ if f.widPresent || f.precPresent {
+ // Account 3 extra bytes for possible addition of a sign and "0x".
+ width := 3 + f.wid + f.prec // wid and prec are always positive.
+ if width > len(buf) {
+ // We're going to need a bigger boat.
+ buf = make([]byte, width)
+ }
+ }
+
+ // Two ways to ask for extra leading zero digits: %.3d or %03d.
+ // If both are specified the f.zero flag is ignored and
+ // padding with spaces is used instead.
+ prec := 0
+ if f.precPresent {
+ prec = f.prec
+ // Precision of 0 and value of 0 means "print nothing" but padding.
+ if prec == 0 && u == 0 {
+ oldZero := f.zero
+ f.zero = false
+ f.writePadding(f.wid)
+ f.zero = oldZero
+ return
+ }
+ } else if f.zero && !f.minus && f.widPresent { // Zero padding is allowed only to the left.
+ prec = f.wid
+ if negative || f.plus || f.space {
+ prec-- // leave room for sign
+ }
+ }
+
+ // Because printing is easier right-to-left: format u into buf, ending at buf[i].
+ // We could make things marginally faster by splitting the 32-bit case out
+ // into a separate block but it's not worth the duplication, so u has 64 bits.
+ i := len(buf)
+ // Use constants for the division and modulo for more efficient code.
+ // Switch cases ordered by popularity.
+ switch base {
+ case 10:
+ for u >= 10 {
+ i--
+ next := u / 10
+ buf[i] = byte('0' + u - next*10)
+ u = next
+ }
+ case 16:
+ for u >= 16 {
+ i--
+ buf[i] = digits[u&0xF]
+ u >>= 4
+ }
+ case 8:
+ for u >= 8 {
+ i--
+ buf[i] = byte('0' + u&7)
+ u >>= 3
+ }
+ case 2:
+ for u >= 2 {
+ i--
+ buf[i] = byte('0' + u&1)
+ u >>= 1
+ }
+ default:
+ panic("fmt: unknown base; can't happen")
+ }
+ i--
+ buf[i] = digits[u]
+ for i > 0 && prec > len(buf)-i {
+ i--
+ buf[i] = '0'
+ }
+
+ // Various prefixes: 0x, -, etc.
+ if f.sharp {
+ switch base {
+ case 2:
+ // Add a leading 0b.
+ i--
+ buf[i] = 'b'
+ i--
+ buf[i] = '0'
+ case 8:
+ if buf[i] != '0' {
+ i--
+ buf[i] = '0'
+ }
+ case 16:
+ // Add a leading 0x or 0X.
+ i--
+ buf[i] = digits[16]
+ i--
+ buf[i] = '0'
+ }
+ }
+ if verb == 'O' {
+ i--
+ buf[i] = 'o'
+ i--
+ buf[i] = '0'
+ }
+
+ if negative {
+ i--
+ buf[i] = '-'
+ } else if f.plus {
+ i--
+ buf[i] = '+'
+ } else if f.space {
+ i--
+ buf[i] = ' '
+ }
+
+ // Left padding with zeros has already been handled like precision earlier
+ // or the f.zero flag is ignored due to an explicitly set precision.
+ oldZero := f.zero
+ f.zero = false
+ f.pad(buf[i:])
+ f.zero = oldZero
+}
+
+// truncateString truncates the string s to the specified precision, if present.
+func (f *fmt) truncateString(s string) string {
+ if f.precPresent {
+ n := f.prec
+ for i := range s {
+ n--
+ if n < 0 {
+ return s[:i]
+ }
+ }
+ }
+ return s
+}
+
+// truncate truncates the byte slice b as a string of the specified precision, if present.
+func (f *fmt) truncate(b []byte) []byte {
+ if f.precPresent {
+ n := f.prec
+ for i := 0; i < len(b); {
+ n--
+ if n < 0 {
+ return b[:i]
+ }
+ _, wid := utf8.DecodeRune(b[i:])
+ i += wid
+ }
+ }
+ return b
+}
+
+// fmtS formats a string.
+func (f *fmt) fmtS(s string) {
+ s = f.truncateString(s)
+ f.padString(s)
+}
+
+// fmtBs formats the byte slice b as if it was formatted as string with fmtS.
+func (f *fmt) fmtBs(b []byte) {
+ b = f.truncate(b)
+ f.pad(b)
+}
+
+// fmtSbx formats a string or byte slice as a hexadecimal encoding of its bytes.
+func (f *fmt) fmtSbx(s string, b []byte, digits string) {
+ length := len(b)
+ if b == nil {
+ // No byte slice present. Assume string s should be encoded.
+ length = len(s)
+ }
+ // Set length to not process more bytes than the precision demands.
+ if f.precPresent && f.prec < length {
+ length = f.prec
+ }
+ // Compute width of the encoding taking into account the f.sharp and f.space flag.
+ width := 2 * length
+ if width > 0 {
+ if f.space {
+ // Each element encoded by two hexadecimals will get a leading 0x or 0X.
+ if f.sharp {
+ width *= 2
+ }
+ // Elements will be separated by a space.
+ width += length - 1
+ } else if f.sharp {
+ // Only a leading 0x or 0X will be added for the whole string.
+ width += 2
+ }
+ } else { // The byte slice or string that should be encoded is empty.
+ if f.widPresent {
+ f.writePadding(f.wid)
+ }
+ return
+ }
+ // Handle padding to the left.
+ if f.widPresent && f.wid > width && !f.minus {
+ f.writePadding(f.wid - width)
+ }
+ // Write the encoding directly into the output buffer.
+ buf := *f.buf
+ if f.sharp {
+ // Add leading 0x or 0X.
+ buf = append(buf, '0', digits[16])
+ }
+ var c byte
+ for i := 0; i < length; i++ {
+ if f.space && i > 0 {
+ // Separate elements with a space.
+ buf = append(buf, ' ')
+ if f.sharp {
+ // Add leading 0x or 0X for each element.
+ buf = append(buf, '0', digits[16])
+ }
+ }
+ if b != nil {
+ c = b[i] // Take a byte from the input byte slice.
+ } else {
+ c = s[i] // Take a byte from the input string.
+ }
+ // Encode each byte as two hexadecimal digits.
+ buf = append(buf, digits[c>>4], digits[c&0xF])
+ }
+ *f.buf = buf
+ // Handle padding to the right.
+ if f.widPresent && f.wid > width && f.minus {
+ f.writePadding(f.wid - width)
+ }
+}
+
+// fmtSx formats a string as a hexadecimal encoding of its bytes.
+func (f *fmt) fmtSx(s, digits string) {
+ f.fmtSbx(s, nil, digits)
+}
+
+// fmtBx formats a byte slice as a hexadecimal encoding of its bytes.
+func (f *fmt) fmtBx(b []byte, digits string) {
+ f.fmtSbx("", b, digits)
+}
+
+// fmtQ formats a string as a double-quoted, escaped Go string constant.
+// If f.sharp is set a raw (backquoted) string may be returned instead
+// if the string does not contain any control characters other than tab.
+func (f *fmt) fmtQ(s string) {
+ s = f.truncateString(s)
+ if f.sharp && strconv.CanBackquote(s) {
+ f.padString("`" + s + "`")
+ return
+ }
+ buf := f.intbuf[:0]
+ if f.plus {
+ f.pad(strconv.AppendQuoteToASCII(buf, s))
+ } else {
+ f.pad(strconv.AppendQuote(buf, s))
+ }
+}
+
+// fmtC formats an integer as a Unicode character.
+// If the character is not valid Unicode, it will print '\ufffd'.
+func (f *fmt) fmtC(c uint64) {
+ // Explicitly check whether c exceeds utf8.MaxRune since the conversion
+ // of a uint64 to a rune may lose precision that indicates an overflow.
+ r := rune(c)
+ if c > utf8.MaxRune {
+ r = utf8.RuneError
+ }
+ buf := f.intbuf[:0]
+ f.pad(utf8.AppendRune(buf, r))
+}
+
+// fmtQc formats an integer as a single-quoted, escaped Go character constant.
+// If the character is not valid Unicode, it will print '\ufffd'.
+func (f *fmt) fmtQc(c uint64) {
+ r := rune(c)
+ if c > utf8.MaxRune {
+ r = utf8.RuneError
+ }
+ buf := f.intbuf[:0]
+ if f.plus {
+ f.pad(strconv.AppendQuoteRuneToASCII(buf, r))
+ } else {
+ f.pad(strconv.AppendQuoteRune(buf, r))
+ }
+}
+
+// fmtFloat formats a float64. It assumes that verb is a valid format specifier
+// for strconv.AppendFloat and therefore fits into a byte.
+func (f *fmt) fmtFloat(v float64, size int, verb rune, prec int) {
+ // Explicit precision in format specifier overrules default precision.
+ if f.precPresent {
+ prec = f.prec
+ }
+ // Format number, reserving space for leading + sign if needed.
+ num := strconv.AppendFloat(f.intbuf[:1], v, byte(verb), prec, size)
+ if num[1] == '-' || num[1] == '+' {
+ num = num[1:]
+ } else {
+ num[0] = '+'
+ }
+ // f.space means to add a leading space instead of a "+" sign unless
+ // the sign is explicitly asked for by f.plus.
+ if f.space && num[0] == '+' && !f.plus {
+ num[0] = ' '
+ }
+ // Special handling for infinities and NaN,
+ // which don't look like a number so shouldn't be padded with zeros.
+ if num[1] == 'I' || num[1] == 'N' {
+ oldZero := f.zero
+ f.zero = false
+ // Remove sign before NaN if not asked for.
+ if num[1] == 'N' && !f.space && !f.plus {
+ num = num[1:]
+ }
+ f.pad(num)
+ f.zero = oldZero
+ return
+ }
+ // The sharp flag forces printing a decimal point for non-binary formats
+ // and retains trailing zeros, which we may need to restore.
+ if f.sharp && verb != 'b' {
+ digits := 0
+ switch verb {
+ case 'v', 'g', 'G', 'x':
+ digits = prec
+ // If no precision is set explicitly use a precision of 6.
+ if digits == -1 {
+ digits = 6
+ }
+ }
+
+ // Buffer pre-allocated with enough room for
+ // exponent notations of the form "e+123" or "p-1023".
+ var tailBuf [6]byte
+ tail := tailBuf[:0]
+
+ hasDecimalPoint := false
+ sawNonzeroDigit := false
+ // Starting from i = 1 to skip sign at num[0].
+ for i := 1; i < len(num); i++ {
+ switch num[i] {
+ case '.':
+ hasDecimalPoint = true
+ case 'p', 'P':
+ tail = append(tail, num[i:]...)
+ num = num[:i]
+ case 'e', 'E':
+ if verb != 'x' && verb != 'X' {
+ tail = append(tail, num[i:]...)
+ num = num[:i]
+ break
+ }
+ fallthrough
+ default:
+ if num[i] != '0' {
+ sawNonzeroDigit = true
+ }
+ // Count significant digits after the first non-zero digit.
+ if sawNonzeroDigit {
+ digits--
+ }
+ }
+ }
+ if !hasDecimalPoint {
+ // Leading digit 0 should contribute once to digits.
+ if len(num) == 2 && num[1] == '0' {
+ digits--
+ }
+ num = append(num, '.')
+ }
+ for digits > 0 {
+ num = append(num, '0')
+ digits--
+ }
+ num = append(num, tail...)
+ }
+ // We want a sign if asked for and if the sign is not positive.
+ if f.plus || num[0] != '+' {
+ // If we're zero padding to the left we want the sign before the leading zeros.
+ // Achieve this by writing the sign out and then padding the unsigned number.
+ // Zero padding is allowed only to the left.
+ if f.zero && !f.minus && f.widPresent && f.wid > len(num) {
+ f.buf.writeByte(num[0])
+ f.writePadding(f.wid - len(num))
+ f.buf.write(num[1:])
+ return
+ }
+ f.pad(num)
+ return
+ }
+ // No sign to show and the number is positive; just print the unsigned number.
+ f.pad(num[1:])
+}
diff --git a/go/src/fmt/gostringer_example_test.go b/go/src/fmt/gostringer_example_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..ab19ee3b94d2e310c8962e85aed95cabd0203bd2
--- /dev/null
+++ b/go/src/fmt/gostringer_example_test.go
@@ -0,0 +1,59 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package fmt_test
+
+import (
+ "fmt"
+)
+
+// Address has a City, State and a Country.
+type Address struct {
+ City string
+ State string
+ Country string
+}
+
+// Person has a Name, Age and Address.
+type Person struct {
+ Name string
+ Age uint
+ Addr *Address
+}
+
+// GoString makes Person satisfy the GoStringer interface.
+// The return value is valid Go code that can be used to reproduce the Person struct.
+func (p Person) GoString() string {
+ if p.Addr != nil {
+ return fmt.Sprintf("Person{Name: %q, Age: %d, Addr: &Address{City: %q, State: %q, Country: %q}}", p.Name, int(p.Age), p.Addr.City, p.Addr.State, p.Addr.Country)
+ }
+ return fmt.Sprintf("Person{Name: %q, Age: %d}", p.Name, int(p.Age))
+}
+
+func ExampleGoStringer() {
+ p1 := Person{
+ Name: "Warren",
+ Age: 31,
+ Addr: &Address{
+ City: "Denver",
+ State: "CO",
+ Country: "U.S.A.",
+ },
+ }
+ // If GoString() wasn't implemented, the output of `fmt.Printf("%#v", p1)` would be similar to
+ // Person{Name:"Warren", Age:0x1f, Addr:(*main.Address)(0x10448240)}
+ fmt.Printf("%#v\n", p1)
+
+ p2 := Person{
+ Name: "Theia",
+ Age: 4,
+ }
+ // If GoString() wasn't implemented, the output of `fmt.Printf("%#v", p2)` would be similar to
+ // Person{Name:"Theia", Age:0x4, Addr:(*main.Address)(nil)}
+ fmt.Printf("%#v\n", p2)
+
+ // Output:
+ // Person{Name: "Warren", Age: 31, Addr: &Address{City: "Denver", State: "CO", Country: "U.S.A."}}
+ // Person{Name: "Theia", Age: 4}
+}
diff --git a/go/src/fmt/print.go b/go/src/fmt/print.go
new file mode 100644
index 0000000000000000000000000000000000000000..2340ceed8f294488d73d28e1ffd26a3fa67a2eb1
--- /dev/null
+++ b/go/src/fmt/print.go
@@ -0,0 +1,1221 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package fmt
+
+import (
+ "internal/fmtsort"
+ "io"
+ "os"
+ "reflect"
+ "strconv"
+ "sync"
+ "unicode/utf8"
+)
+
+// Strings for use with buffer.WriteString.
+// This is less overhead than using buffer.Write with byte arrays.
+const (
+ commaSpaceString = ", "
+ nilAngleString = ""
+ nilParenString = "(nil)"
+ nilString = "nil"
+ mapString = "map["
+ percentBangString = "%!"
+ missingString = "(MISSING)"
+ badIndexString = "(BADINDEX)"
+ panicString = "(PANIC="
+ extraString = "%!(EXTRA "
+ badWidthString = "%!(BADWIDTH)"
+ badPrecString = "%!(BADPREC)"
+ noVerbString = "%!(NOVERB)"
+ invReflectString = ""
+)
+
+// State represents the printer state passed to custom formatters.
+// It provides access to the [io.Writer] interface plus information about
+// the flags and options for the operand's format specifier.
+type State interface {
+ // Write is the function to call to emit formatted output to be printed.
+ Write(b []byte) (n int, err error)
+ // Width returns the value of the width option and whether it has been set.
+ Width() (wid int, ok bool)
+ // Precision returns the value of the precision option and whether it has been set.
+ Precision() (prec int, ok bool)
+
+ // Flag reports whether the flag c, a character, has been set.
+ Flag(c int) bool
+}
+
+// Formatter is implemented by any value that has a Format method.
+// The implementation controls how [State] and rune are interpreted,
+// and may call [Sprint] or [Fprint](f) etc. to generate its output.
+type Formatter interface {
+ Format(f State, verb rune)
+}
+
+// Stringer is implemented by any value that has a String method,
+// which defines the “native” format for that value.
+// The String method is used to print values passed as an operand
+// to any format that accepts a string or to an unformatted printer
+// such as [Print].
+type Stringer interface {
+ String() string
+}
+
+// GoStringer is implemented by any value that has a GoString method,
+// which defines the Go syntax for that value.
+// The GoString method is used to print values passed as an operand
+// to a %#v format.
+type GoStringer interface {
+ GoString() string
+}
+
+// FormatString returns a string representing the fully qualified formatting
+// directive captured by the [State], followed by the argument verb. ([State] does not
+// itself contain the verb.) The result has a leading percent sign followed by any
+// flags, the width, and the precision. Missing flags, width, and precision are
+// omitted. This function allows a [Formatter] to reconstruct the original
+// directive triggering the call to Format.
+func FormatString(state State, verb rune) string {
+ var tmp [16]byte // Use a local buffer.
+ b := append(tmp[:0], '%')
+ for _, c := range " +-#0" { // All known flags
+ if state.Flag(int(c)) { // The argument is an int for historical reasons.
+ b = append(b, byte(c))
+ }
+ }
+ if w, ok := state.Width(); ok {
+ b = strconv.AppendInt(b, int64(w), 10)
+ }
+ if p, ok := state.Precision(); ok {
+ b = append(b, '.')
+ b = strconv.AppendInt(b, int64(p), 10)
+ }
+ b = utf8.AppendRune(b, verb)
+ return string(b)
+}
+
+// Use simple []byte instead of bytes.Buffer to avoid large dependency.
+type buffer []byte
+
+func (b *buffer) write(p []byte) {
+ *b = append(*b, p...)
+}
+
+func (b *buffer) writeString(s string) {
+ *b = append(*b, s...)
+}
+
+func (b *buffer) writeByte(c byte) {
+ *b = append(*b, c)
+}
+
+func (b *buffer) writeRune(r rune) {
+ *b = utf8.AppendRune(*b, r)
+}
+
+// pp is used to store a printer's state and is reused with sync.Pool to avoid allocations.
+type pp struct {
+ buf buffer
+
+ // arg holds the current item, as an interface{}.
+ arg any
+
+ // value is used instead of arg for reflect values.
+ value reflect.Value
+
+ // fmt is used to format basic items such as integers or strings.
+ fmt fmt
+
+ // reordered records whether the format string used argument reordering.
+ reordered bool
+ // goodArgNum records whether the most recent reordering directive was valid.
+ goodArgNum bool
+ // panicking is set by catchPanic to avoid infinite panic, recover, panic, ... recursion.
+ panicking bool
+ // erroring is set when printing an error string to guard against calling handleMethods.
+ erroring bool
+ // wrapErrs is set when the format string may contain a %w verb.
+ wrapErrs bool
+ // wrappedErrs records the targets of the %w verb.
+ wrappedErrs []int
+}
+
+var ppFree = sync.Pool{
+ New: func() any { return new(pp) },
+}
+
+// newPrinter allocates a new pp struct or grabs a cached one.
+func newPrinter() *pp {
+ p := ppFree.Get().(*pp)
+ p.panicking = false
+ p.erroring = false
+ p.wrapErrs = false
+ p.fmt.init(&p.buf)
+ return p
+}
+
+// free saves used pp structs in ppFree; avoids an allocation per invocation.
+func (p *pp) free() {
+ // Proper usage of a sync.Pool requires each entry to have approximately
+ // the same memory cost. To obtain this property when the stored type
+ // contains a variably-sized buffer, we add a hard limit on the maximum
+ // buffer to place back in the pool. If the buffer is larger than the
+ // limit, we drop the buffer and recycle just the printer.
+ //
+ // See https://golang.org/issue/23199.
+ if cap(p.buf) > 64*1024 {
+ p.buf = nil
+ } else {
+ p.buf = p.buf[:0]
+ }
+ if cap(p.wrappedErrs) > 8 {
+ p.wrappedErrs = nil
+ }
+
+ p.arg = nil
+ p.value = reflect.Value{}
+ p.wrappedErrs = p.wrappedErrs[:0]
+ ppFree.Put(p)
+}
+
+func (p *pp) Width() (wid int, ok bool) { return p.fmt.wid, p.fmt.widPresent }
+
+func (p *pp) Precision() (prec int, ok bool) { return p.fmt.prec, p.fmt.precPresent }
+
+func (p *pp) Flag(b int) bool {
+ switch b {
+ case '-':
+ return p.fmt.minus
+ case '+':
+ return p.fmt.plus || p.fmt.plusV
+ case '#':
+ return p.fmt.sharp || p.fmt.sharpV
+ case ' ':
+ return p.fmt.space
+ case '0':
+ return p.fmt.zero
+ }
+ return false
+}
+
+// Write implements [io.Writer] so we can call [Fprintf] on a pp (through [State]), for
+// recursive use in custom verbs.
+func (p *pp) Write(b []byte) (ret int, err error) {
+ p.buf.write(b)
+ return len(b), nil
+}
+
+// WriteString implements [io.StringWriter] so that we can call [io.WriteString]
+// on a pp (through state), for efficiency.
+func (p *pp) WriteString(s string) (ret int, err error) {
+ p.buf.writeString(s)
+ return len(s), nil
+}
+
+// These routines end in 'f' and take a format string.
+
+// Fprintf formats according to a format specifier and writes to w.
+// It returns the number of bytes written and any write error encountered.
+func Fprintf(w io.Writer, format string, a ...any) (n int, err error) {
+ p := newPrinter()
+ p.doPrintf(format, a)
+ n, err = w.Write(p.buf)
+ p.free()
+ return
+}
+
+// Printf formats according to a format specifier and writes to standard output.
+// It returns the number of bytes written and any write error encountered.
+func Printf(format string, a ...any) (n int, err error) {
+ return Fprintf(os.Stdout, format, a...)
+}
+
+// Sprintf formats according to a format specifier and returns the resulting string.
+func Sprintf(format string, a ...any) string {
+ p := newPrinter()
+ p.doPrintf(format, a)
+ s := string(p.buf)
+ p.free()
+ return s
+}
+
+// Appendf formats according to a format specifier, appends the result to the byte
+// slice, and returns the updated slice.
+func Appendf(b []byte, format string, a ...any) []byte {
+ p := newPrinter()
+ p.doPrintf(format, a)
+ b = append(b, p.buf...)
+ p.free()
+ return b
+}
+
+// These routines do not take a format string
+
+// Fprint formats using the default formats for its operands and writes to w.
+// Spaces are added between operands when neither is a string.
+// It returns the number of bytes written and any write error encountered.
+func Fprint(w io.Writer, a ...any) (n int, err error) {
+ p := newPrinter()
+ p.doPrint(a)
+ n, err = w.Write(p.buf)
+ p.free()
+ return
+}
+
+// Print formats using the default formats for its operands and writes to standard output.
+// Spaces are added between operands when neither is a string.
+// It returns the number of bytes written and any write error encountered.
+func Print(a ...any) (n int, err error) {
+ return Fprint(os.Stdout, a...)
+}
+
+// Sprint formats using the default formats for its operands and returns the resulting string.
+// Spaces are added between operands when neither is a string.
+func Sprint(a ...any) string {
+ p := newPrinter()
+ p.doPrint(a)
+ s := string(p.buf)
+ p.free()
+ return s
+}
+
+// Append formats using the default formats for its operands, appends the result to
+// the byte slice, and returns the updated slice.
+// Spaces are added between operands when neither is a string.
+func Append(b []byte, a ...any) []byte {
+ p := newPrinter()
+ p.doPrint(a)
+ b = append(b, p.buf...)
+ p.free()
+ return b
+}
+
+// These routines end in 'ln', do not take a format string,
+// always add spaces between operands, and add a newline
+// after the last operand.
+
+// Fprintln formats using the default formats for its operands and writes to w.
+// Spaces are always added between operands and a newline is appended.
+// It returns the number of bytes written and any write error encountered.
+func Fprintln(w io.Writer, a ...any) (n int, err error) {
+ p := newPrinter()
+ p.doPrintln(a)
+ n, err = w.Write(p.buf)
+ p.free()
+ return
+}
+
+// Println formats using the default formats for its operands and writes to standard output.
+// Spaces are always added between operands and a newline is appended.
+// It returns the number of bytes written and any write error encountered.
+func Println(a ...any) (n int, err error) {
+ return Fprintln(os.Stdout, a...)
+}
+
+// Sprintln formats using the default formats for its operands and returns the resulting string.
+// Spaces are always added between operands and a newline is appended.
+func Sprintln(a ...any) string {
+ p := newPrinter()
+ p.doPrintln(a)
+ s := string(p.buf)
+ p.free()
+ return s
+}
+
+// Appendln formats using the default formats for its operands, appends the result
+// to the byte slice, and returns the updated slice. Spaces are always added
+// between operands and a newline is appended.
+func Appendln(b []byte, a ...any) []byte {
+ p := newPrinter()
+ p.doPrintln(a)
+ b = append(b, p.buf...)
+ p.free()
+ return b
+}
+
+// getField gets the i'th field of the struct value.
+// If the field itself is a non-nil interface, return a value for
+// the thing inside the interface, not the interface itself.
+func getField(v reflect.Value, i int) reflect.Value {
+ val := v.Field(i)
+ if val.Kind() == reflect.Interface && !val.IsNil() {
+ val = val.Elem()
+ }
+ return val
+}
+
+// tooLarge reports whether the magnitude of the integer is
+// too large to be used as a formatting width or precision.
+func tooLarge(x int) bool {
+ const max int = 1e6
+ return x > max || x < -max
+}
+
+// parsenum converts ASCII to integer. num is 0 (and isnum is false) if no number present.
+func parsenum(s string, start, end int) (num int, isnum bool, newi int) {
+ if start >= end {
+ return 0, false, end
+ }
+ for newi = start; newi < end && '0' <= s[newi] && s[newi] <= '9'; newi++ {
+ if tooLarge(num) {
+ return 0, false, end // Overflow; crazy long number most likely.
+ }
+ num = num*10 + int(s[newi]-'0')
+ isnum = true
+ }
+ return
+}
+
+func (p *pp) unknownType(v reflect.Value) {
+ if !v.IsValid() {
+ p.buf.writeString(nilAngleString)
+ return
+ }
+ p.buf.writeByte('?')
+ p.buf.writeString(v.Type().String())
+ p.buf.writeByte('?')
+}
+
+func (p *pp) badVerb(verb rune) {
+ p.erroring = true
+ p.buf.writeString(percentBangString)
+ p.buf.writeRune(verb)
+ p.buf.writeByte('(')
+ switch {
+ case p.arg != nil:
+ p.buf.writeString(reflect.TypeOf(p.arg).String())
+ p.buf.writeByte('=')
+ p.printArg(p.arg, 'v')
+ case p.value.IsValid():
+ p.buf.writeString(p.value.Type().String())
+ p.buf.writeByte('=')
+ p.printValue(p.value, 'v', 0)
+ default:
+ p.buf.writeString(nilAngleString)
+ }
+ p.buf.writeByte(')')
+ p.erroring = false
+}
+
+func (p *pp) fmtBool(v bool, verb rune) {
+ switch verb {
+ case 't', 'v':
+ p.fmt.fmtBoolean(v)
+ default:
+ p.badVerb(verb)
+ }
+}
+
+// fmt0x64 formats a uint64 in hexadecimal and prefixes it with 0x or
+// not, as requested, by temporarily setting the sharp flag.
+func (p *pp) fmt0x64(v uint64, leading0x bool) {
+ sharp := p.fmt.sharp
+ p.fmt.sharp = leading0x
+ p.fmt.fmtInteger(v, 16, unsigned, 'v', ldigits)
+ p.fmt.sharp = sharp
+}
+
+// fmtInteger formats a signed or unsigned integer.
+func (p *pp) fmtInteger(v uint64, isSigned bool, verb rune) {
+ switch verb {
+ case 'v':
+ if p.fmt.sharpV && !isSigned {
+ p.fmt0x64(v, true)
+ } else {
+ p.fmt.fmtInteger(v, 10, isSigned, verb, ldigits)
+ }
+ case 'd':
+ p.fmt.fmtInteger(v, 10, isSigned, verb, ldigits)
+ case 'b':
+ p.fmt.fmtInteger(v, 2, isSigned, verb, ldigits)
+ case 'o', 'O':
+ p.fmt.fmtInteger(v, 8, isSigned, verb, ldigits)
+ case 'x':
+ p.fmt.fmtInteger(v, 16, isSigned, verb, ldigits)
+ case 'X':
+ p.fmt.fmtInteger(v, 16, isSigned, verb, udigits)
+ case 'c':
+ p.fmt.fmtC(v)
+ case 'q':
+ p.fmt.fmtQc(v)
+ case 'U':
+ p.fmt.fmtUnicode(v)
+ default:
+ p.badVerb(verb)
+ }
+}
+
+// fmtFloat formats a float. The default precision for each verb
+// is specified as last argument in the call to fmt_float.
+func (p *pp) fmtFloat(v float64, size int, verb rune) {
+ switch verb {
+ case 'v':
+ p.fmt.fmtFloat(v, size, 'g', -1)
+ case 'b', 'g', 'G', 'x', 'X':
+ p.fmt.fmtFloat(v, size, verb, -1)
+ case 'f', 'e', 'E':
+ p.fmt.fmtFloat(v, size, verb, 6)
+ case 'F':
+ p.fmt.fmtFloat(v, size, 'f', 6)
+ default:
+ p.badVerb(verb)
+ }
+}
+
+// fmtComplex formats a complex number v with
+// r = real(v) and j = imag(v) as (r+ji) using
+// fmtFloat for r and j formatting.
+func (p *pp) fmtComplex(v complex128, size int, verb rune) {
+ // Make sure any unsupported verbs are found before the
+ // calls to fmtFloat to not generate an incorrect error string.
+ switch verb {
+ case 'v', 'b', 'g', 'G', 'x', 'X', 'f', 'F', 'e', 'E':
+ oldPlus := p.fmt.plus
+ p.buf.writeByte('(')
+ p.fmtFloat(real(v), size/2, verb)
+ // Imaginary part always has a sign.
+ p.fmt.plus = true
+ p.fmtFloat(imag(v), size/2, verb)
+ p.buf.writeString("i)")
+ p.fmt.plus = oldPlus
+ default:
+ p.badVerb(verb)
+ }
+}
+
+func (p *pp) fmtString(v string, verb rune) {
+ switch verb {
+ case 'v':
+ if p.fmt.sharpV {
+ p.fmt.fmtQ(v)
+ } else {
+ p.fmt.fmtS(v)
+ }
+ case 's':
+ p.fmt.fmtS(v)
+ case 'x':
+ p.fmt.fmtSx(v, ldigits)
+ case 'X':
+ p.fmt.fmtSx(v, udigits)
+ case 'q':
+ p.fmt.fmtQ(v)
+ default:
+ p.badVerb(verb)
+ }
+}
+
+func (p *pp) fmtBytes(v []byte, verb rune, typeString string) {
+ switch verb {
+ case 'v', 'd':
+ if p.fmt.sharpV {
+ p.buf.writeString(typeString)
+ if v == nil {
+ p.buf.writeString(nilParenString)
+ return
+ }
+ p.buf.writeByte('{')
+ for i, c := range v {
+ if i > 0 {
+ p.buf.writeString(commaSpaceString)
+ }
+ p.fmt0x64(uint64(c), true)
+ }
+ p.buf.writeByte('}')
+ } else {
+ p.buf.writeByte('[')
+ for i, c := range v {
+ if i > 0 {
+ p.buf.writeByte(' ')
+ }
+ p.fmt.fmtInteger(uint64(c), 10, unsigned, verb, ldigits)
+ }
+ p.buf.writeByte(']')
+ }
+ case 's':
+ p.fmt.fmtBs(v)
+ case 'x':
+ p.fmt.fmtBx(v, ldigits)
+ case 'X':
+ p.fmt.fmtBx(v, udigits)
+ case 'q':
+ p.fmt.fmtQ(string(v))
+ default:
+ p.printValue(reflect.ValueOf(v), verb, 0)
+ }
+}
+
+func (p *pp) fmtPointer(value reflect.Value, verb rune) {
+ var u uintptr
+ switch value.Kind() {
+ case reflect.Chan, reflect.Func, reflect.Map, reflect.Pointer, reflect.Slice, reflect.UnsafePointer:
+ u = uintptr(value.UnsafePointer())
+ default:
+ p.badVerb(verb)
+ return
+ }
+
+ switch verb {
+ case 'v':
+ if p.fmt.sharpV {
+ p.buf.writeByte('(')
+ p.buf.writeString(value.Type().String())
+ p.buf.writeString(")(")
+ if u == 0 {
+ p.buf.writeString(nilString)
+ } else {
+ p.fmt0x64(uint64(u), true)
+ }
+ p.buf.writeByte(')')
+ } else {
+ if u == 0 {
+ p.fmt.padString(nilAngleString)
+ } else {
+ p.fmt0x64(uint64(u), !p.fmt.sharp)
+ }
+ }
+ case 'p':
+ p.fmt0x64(uint64(u), !p.fmt.sharp)
+ case 'b', 'o', 'd', 'x', 'X':
+ p.fmtInteger(uint64(u), unsigned, verb)
+ default:
+ p.badVerb(verb)
+ }
+}
+
+func (p *pp) catchPanic(arg any, verb rune, method string) {
+ if err := recover(); err != nil {
+ // If it's a nil pointer, just say "". The likeliest causes are a
+ // Stringer that fails to guard against nil or a nil pointer for a
+ // value receiver, and in either case, "" is a nice result.
+ if v := reflect.ValueOf(arg); v.Kind() == reflect.Pointer && v.IsNil() {
+ p.buf.writeString(nilAngleString)
+ return
+ }
+ // Otherwise print a concise panic message. Most of the time the panic
+ // value will print itself nicely.
+ if p.panicking {
+ // Nested panics; the recursion in printArg cannot succeed.
+ panic(err)
+ }
+
+ oldFlags := p.fmt.fmtFlags
+ // For this output we want default behavior.
+ p.fmt.clearflags()
+
+ p.buf.writeString(percentBangString)
+ p.buf.writeRune(verb)
+ p.buf.writeString(panicString)
+ p.buf.writeString(method)
+ p.buf.writeString(" method: ")
+ p.panicking = true
+ p.printArg(err, 'v')
+ p.panicking = false
+ p.buf.writeByte(')')
+
+ p.fmt.fmtFlags = oldFlags
+ }
+}
+
+func (p *pp) handleMethods(verb rune) (handled bool) {
+ if p.erroring {
+ return
+ }
+ if verb == 'w' {
+ // It is invalid to use %w other than with Errorf or with a non-error arg.
+ _, ok := p.arg.(error)
+ if !ok || !p.wrapErrs {
+ p.badVerb(verb)
+ return true
+ }
+ // If the arg is a Formatter, pass 'v' as the verb to it.
+ verb = 'v'
+ }
+
+ // Is it a Formatter?
+ if formatter, ok := p.arg.(Formatter); ok {
+ handled = true
+ defer p.catchPanic(p.arg, verb, "Format")
+ formatter.Format(p, verb)
+ return
+ }
+
+ // If we're doing Go syntax and the argument knows how to supply it, take care of it now.
+ if p.fmt.sharpV {
+ if stringer, ok := p.arg.(GoStringer); ok {
+ handled = true
+ defer p.catchPanic(p.arg, verb, "GoString")
+ // Print the result of GoString unadorned.
+ p.fmt.fmtS(stringer.GoString())
+ return
+ }
+ } else {
+ // If a string is acceptable according to the format, see if
+ // the value satisfies one of the string-valued interfaces.
+ // Println etc. set verb to %v, which is "stringable".
+ switch verb {
+ case 'v', 's', 'x', 'X', 'q':
+ // Is it an error or Stringer?
+ // The duplication in the bodies is necessary:
+ // setting handled and deferring catchPanic
+ // must happen before calling the method.
+ switch v := p.arg.(type) {
+ case error:
+ handled = true
+ defer p.catchPanic(p.arg, verb, "Error")
+ p.fmtString(v.Error(), verb)
+ return
+
+ case Stringer:
+ handled = true
+ defer p.catchPanic(p.arg, verb, "String")
+ p.fmtString(v.String(), verb)
+ return
+ }
+ }
+ }
+ return false
+}
+
+func (p *pp) printArg(arg any, verb rune) {
+ p.arg = arg
+ p.value = reflect.Value{}
+
+ if arg == nil {
+ switch verb {
+ case 'T', 'v':
+ p.fmt.padString(nilAngleString)
+ default:
+ p.badVerb(verb)
+ }
+ return
+ }
+
+ // Special processing considerations.
+ // %T (the value's type) and %p (its address) are special; we always do them first.
+ switch verb {
+ case 'T':
+ p.fmt.fmtS(reflect.TypeOf(arg).String())
+ return
+ case 'p':
+ p.fmtPointer(reflect.ValueOf(arg), 'p')
+ return
+ }
+
+ // Some types can be done without reflection.
+ switch f := arg.(type) {
+ case bool:
+ p.fmtBool(f, verb)
+ case float32:
+ p.fmtFloat(float64(f), 32, verb)
+ case float64:
+ p.fmtFloat(f, 64, verb)
+ case complex64:
+ p.fmtComplex(complex128(f), 64, verb)
+ case complex128:
+ p.fmtComplex(f, 128, verb)
+ case int:
+ p.fmtInteger(uint64(f), signed, verb)
+ case int8:
+ p.fmtInteger(uint64(f), signed, verb)
+ case int16:
+ p.fmtInteger(uint64(f), signed, verb)
+ case int32:
+ p.fmtInteger(uint64(f), signed, verb)
+ case int64:
+ p.fmtInteger(uint64(f), signed, verb)
+ case uint:
+ p.fmtInteger(uint64(f), unsigned, verb)
+ case uint8:
+ p.fmtInteger(uint64(f), unsigned, verb)
+ case uint16:
+ p.fmtInteger(uint64(f), unsigned, verb)
+ case uint32:
+ p.fmtInteger(uint64(f), unsigned, verb)
+ case uint64:
+ p.fmtInteger(f, unsigned, verb)
+ case uintptr:
+ p.fmtInteger(uint64(f), unsigned, verb)
+ case string:
+ p.fmtString(f, verb)
+ case []byte:
+ p.fmtBytes(f, verb, "[]byte")
+ case reflect.Value:
+ // Handle extractable values with special methods
+ // since printValue does not handle them at depth 0.
+ if f.IsValid() && f.CanInterface() {
+ p.arg = f.Interface()
+ if p.handleMethods(verb) {
+ return
+ }
+ }
+ p.printValue(f, verb, 0)
+ default:
+ // If the type is not simple, it might have methods.
+ if !p.handleMethods(verb) {
+ // Need to use reflection, since the type had no
+ // interface methods that could be used for formatting.
+ p.printValue(reflect.ValueOf(f), verb, 0)
+ }
+ }
+}
+
+// printValue is similar to printArg but starts with a reflect value, not an interface{} value.
+// It does not handle 'p' and 'T' verbs because these should have been already handled by printArg.
+func (p *pp) printValue(value reflect.Value, verb rune, depth int) {
+ // Handle values with special methods if not already handled by printArg (depth == 0).
+ if depth > 0 && value.IsValid() && value.CanInterface() {
+ p.arg = value.Interface()
+ if p.handleMethods(verb) {
+ return
+ }
+ }
+ p.arg = nil
+ p.value = value
+
+ switch f := value; value.Kind() {
+ case reflect.Invalid:
+ if depth == 0 {
+ p.buf.writeString(invReflectString)
+ } else {
+ switch verb {
+ case 'v':
+ p.buf.writeString(nilAngleString)
+ default:
+ p.badVerb(verb)
+ }
+ }
+ case reflect.Bool:
+ p.fmtBool(f.Bool(), verb)
+ case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+ p.fmtInteger(uint64(f.Int()), signed, verb)
+ case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+ p.fmtInteger(f.Uint(), unsigned, verb)
+ case reflect.Float32:
+ p.fmtFloat(f.Float(), 32, verb)
+ case reflect.Float64:
+ p.fmtFloat(f.Float(), 64, verb)
+ case reflect.Complex64:
+ p.fmtComplex(f.Complex(), 64, verb)
+ case reflect.Complex128:
+ p.fmtComplex(f.Complex(), 128, verb)
+ case reflect.String:
+ p.fmtString(f.String(), verb)
+ case reflect.Map:
+ if p.fmt.sharpV {
+ p.buf.writeString(f.Type().String())
+ if f.IsNil() {
+ p.buf.writeString(nilParenString)
+ return
+ }
+ p.buf.writeByte('{')
+ } else {
+ p.buf.writeString(mapString)
+ }
+ sorted := fmtsort.Sort(f)
+ for i, m := range sorted {
+ if i > 0 {
+ if p.fmt.sharpV {
+ p.buf.writeString(commaSpaceString)
+ } else {
+ p.buf.writeByte(' ')
+ }
+ }
+ p.printValue(m.Key, verb, depth+1)
+ p.buf.writeByte(':')
+ p.printValue(m.Value, verb, depth+1)
+ }
+ if p.fmt.sharpV {
+ p.buf.writeByte('}')
+ } else {
+ p.buf.writeByte(']')
+ }
+ case reflect.Struct:
+ if p.fmt.sharpV {
+ p.buf.writeString(f.Type().String())
+ }
+ p.buf.writeByte('{')
+ for i := 0; i < f.NumField(); i++ {
+ if i > 0 {
+ if p.fmt.sharpV {
+ p.buf.writeString(commaSpaceString)
+ } else {
+ p.buf.writeByte(' ')
+ }
+ }
+ if p.fmt.plusV || p.fmt.sharpV {
+ if name := f.Type().Field(i).Name; name != "" {
+ p.buf.writeString(name)
+ p.buf.writeByte(':')
+ }
+ }
+ p.printValue(getField(f, i), verb, depth+1)
+ }
+ p.buf.writeByte('}')
+ case reflect.Interface:
+ value := f.Elem()
+ if !value.IsValid() {
+ if p.fmt.sharpV {
+ p.buf.writeString(f.Type().String())
+ p.buf.writeString(nilParenString)
+ } else {
+ p.buf.writeString(nilAngleString)
+ }
+ } else {
+ p.printValue(value, verb, depth+1)
+ }
+ case reflect.Array, reflect.Slice:
+ switch verb {
+ case 's', 'q', 'x', 'X':
+ // Handle byte and uint8 slices and arrays special for the above verbs.
+ t := f.Type()
+ if t.Elem().Kind() == reflect.Uint8 {
+ var bytes []byte
+ if f.Kind() == reflect.Slice || f.CanAddr() {
+ bytes = f.Bytes()
+ } else {
+ // We have an array, but we cannot Bytes() a non-addressable array,
+ // so we build a slice by hand. This is a rare case but it would be nice
+ // if reflection could help a little more.
+ bytes = make([]byte, f.Len())
+ for i := range bytes {
+ bytes[i] = byte(f.Index(i).Uint())
+ }
+ }
+ p.fmtBytes(bytes, verb, t.String())
+ return
+ }
+ }
+ if p.fmt.sharpV {
+ p.buf.writeString(f.Type().String())
+ if f.Kind() == reflect.Slice && f.IsNil() {
+ p.buf.writeString(nilParenString)
+ return
+ }
+ p.buf.writeByte('{')
+ for i := 0; i < f.Len(); i++ {
+ if i > 0 {
+ p.buf.writeString(commaSpaceString)
+ }
+ p.printValue(f.Index(i), verb, depth+1)
+ }
+ p.buf.writeByte('}')
+ } else {
+ p.buf.writeByte('[')
+ for i := 0; i < f.Len(); i++ {
+ if i > 0 {
+ p.buf.writeByte(' ')
+ }
+ p.printValue(f.Index(i), verb, depth+1)
+ }
+ p.buf.writeByte(']')
+ }
+ case reflect.Pointer:
+ // pointer to array or slice or struct? ok at top level
+ // but not embedded (avoid loops)
+ if depth == 0 && f.UnsafePointer() != nil {
+ switch a := f.Elem(); a.Kind() {
+ case reflect.Array, reflect.Slice, reflect.Struct, reflect.Map:
+ p.buf.writeByte('&')
+ p.printValue(a, verb, depth+1)
+ return
+ }
+ }
+ fallthrough
+ case reflect.Chan, reflect.Func, reflect.UnsafePointer:
+ p.fmtPointer(f, verb)
+ default:
+ p.unknownType(f)
+ }
+}
+
+// intFromArg gets the argNumth element of a. On return, isInt reports whether the argument has integer type.
+func intFromArg(a []any, argNum int) (num int, isInt bool, newArgNum int) {
+ newArgNum = argNum
+ if argNum < len(a) {
+ num, isInt = a[argNum].(int) // Almost always OK.
+ if !isInt {
+ // Work harder.
+ switch v := reflect.ValueOf(a[argNum]); v.Kind() {
+ case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+ n := v.Int()
+ if int64(int(n)) == n {
+ num = int(n)
+ isInt = true
+ }
+ case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+ n := v.Uint()
+ if int64(n) >= 0 && uint64(int(n)) == n {
+ num = int(n)
+ isInt = true
+ }
+ default:
+ // Already 0, false.
+ }
+ }
+ newArgNum = argNum + 1
+ if tooLarge(num) {
+ num = 0
+ isInt = false
+ }
+ }
+ return
+}
+
+// parseArgNumber returns the value of the bracketed number, minus 1
+// (explicit argument numbers are one-indexed but we want zero-indexed).
+// The opening bracket is known to be present at format[0].
+// The returned values are the index, the number of bytes to consume
+// up to the closing paren, if present, and whether the number parsed
+// ok. The bytes to consume will be 1 if no closing paren is present.
+func parseArgNumber(format string) (index int, wid int, ok bool) {
+ // There must be at least 3 bytes: [n].
+ if len(format) < 3 {
+ return 0, 1, false
+ }
+
+ // Find closing bracket.
+ for i := 1; i < len(format); i++ {
+ if format[i] == ']' {
+ width, ok, newi := parsenum(format, 1, i)
+ if !ok || newi != i {
+ return 0, i + 1, false
+ }
+ return width - 1, i + 1, true // arg numbers are one-indexed and skip paren.
+ }
+ }
+ return 0, 1, false
+}
+
+// argNumber returns the next argument to evaluate, which is either the value of the passed-in
+// argNum or the value of the bracketed integer that begins format[i:]. It also returns
+// the new value of i, that is, the index of the next byte of the format to process.
+func (p *pp) argNumber(argNum int, format string, i int, numArgs int) (newArgNum, newi int, found bool) {
+ if len(format) <= i || format[i] != '[' {
+ return argNum, i, false
+ }
+ p.reordered = true
+ index, wid, ok := parseArgNumber(format[i:])
+ if ok && 0 <= index && index < numArgs {
+ return index, i + wid, true
+ }
+ p.goodArgNum = false
+ return argNum, i + wid, ok
+}
+
+func (p *pp) badArgNum(verb rune) {
+ p.buf.writeString(percentBangString)
+ p.buf.writeRune(verb)
+ p.buf.writeString(badIndexString)
+}
+
+func (p *pp) missingArg(verb rune) {
+ p.buf.writeString(percentBangString)
+ p.buf.writeRune(verb)
+ p.buf.writeString(missingString)
+}
+
+func (p *pp) doPrintf(format string, a []any) {
+ end := len(format)
+ argNum := 0 // we process one argument per non-trivial format
+ afterIndex := false // previous item in format was an index like [3].
+ p.reordered = false
+formatLoop:
+ for i := 0; i < end; {
+ p.goodArgNum = true
+ lasti := i
+ for i < end && format[i] != '%' {
+ i++
+ }
+ if i > lasti {
+ p.buf.writeString(format[lasti:i])
+ }
+ if i >= end {
+ // done processing format string
+ break
+ }
+
+ // Process one verb
+ i++
+
+ // Do we have flags?
+ p.fmt.clearflags()
+ simpleFormat:
+ for ; i < end; i++ {
+ c := format[i]
+ switch c {
+ case '#':
+ p.fmt.sharp = true
+ case '0':
+ p.fmt.zero = true
+ case '+':
+ p.fmt.plus = true
+ case '-':
+ p.fmt.minus = true
+ case ' ':
+ p.fmt.space = true
+ default:
+ // Fast path for common case of ascii lower case simple verbs
+ // without precision or width or argument indices.
+ if 'a' <= c && c <= 'z' && argNum < len(a) {
+ switch c {
+ case 'w':
+ p.wrappedErrs = append(p.wrappedErrs, argNum)
+ fallthrough
+ case 'v':
+ // Go syntax
+ p.fmt.sharpV = p.fmt.sharp
+ p.fmt.sharp = false
+ // Struct-field syntax
+ p.fmt.plusV = p.fmt.plus
+ p.fmt.plus = false
+ }
+ p.printArg(a[argNum], rune(c))
+ argNum++
+ i++
+ continue formatLoop
+ }
+ // Format is more complex than simple flags and a verb or is malformed.
+ break simpleFormat
+ }
+ }
+
+ // Do we have an explicit argument index?
+ argNum, i, afterIndex = p.argNumber(argNum, format, i, len(a))
+
+ // Do we have width?
+ if i < end && format[i] == '*' {
+ i++
+ p.fmt.wid, p.fmt.widPresent, argNum = intFromArg(a, argNum)
+
+ if !p.fmt.widPresent {
+ p.buf.writeString(badWidthString)
+ }
+
+ // We have a negative width, so take its value and ensure
+ // that the minus flag is set
+ if p.fmt.wid < 0 {
+ p.fmt.wid = -p.fmt.wid
+ p.fmt.minus = true
+ p.fmt.zero = false // Do not pad with zeros to the right.
+ }
+ afterIndex = false
+ } else {
+ p.fmt.wid, p.fmt.widPresent, i = parsenum(format, i, end)
+ if afterIndex && p.fmt.widPresent { // "%[3]2d"
+ p.goodArgNum = false
+ }
+ }
+
+ // Do we have precision?
+ if i+1 < end && format[i] == '.' {
+ i++
+ if afterIndex { // "%[3].2d"
+ p.goodArgNum = false
+ }
+ argNum, i, afterIndex = p.argNumber(argNum, format, i, len(a))
+ if i < end && format[i] == '*' {
+ i++
+ p.fmt.prec, p.fmt.precPresent, argNum = intFromArg(a, argNum)
+ // Negative precision arguments don't make sense
+ if p.fmt.prec < 0 {
+ p.fmt.prec = 0
+ p.fmt.precPresent = false
+ }
+ if !p.fmt.precPresent {
+ p.buf.writeString(badPrecString)
+ }
+ afterIndex = false
+ } else {
+ p.fmt.prec, p.fmt.precPresent, i = parsenum(format, i, end)
+ if !p.fmt.precPresent {
+ p.fmt.prec = 0
+ p.fmt.precPresent = true
+ }
+ }
+ }
+
+ if !afterIndex {
+ argNum, i, afterIndex = p.argNumber(argNum, format, i, len(a))
+ }
+
+ if i >= end {
+ p.buf.writeString(noVerbString)
+ break
+ }
+
+ verb, size := utf8.DecodeRuneInString(format[i:])
+ i += size
+
+ switch {
+ case verb == '%': // Percent does not absorb operands and ignores f.wid and f.prec.
+ p.buf.writeByte('%')
+ case !p.goodArgNum:
+ p.badArgNum(verb)
+ case argNum >= len(a): // No argument left over to print for the current verb.
+ p.missingArg(verb)
+ case verb == 'w':
+ p.wrappedErrs = append(p.wrappedErrs, argNum)
+ fallthrough
+ case verb == 'v':
+ // Go syntax
+ p.fmt.sharpV = p.fmt.sharp
+ p.fmt.sharp = false
+ // Struct-field syntax
+ p.fmt.plusV = p.fmt.plus
+ p.fmt.plus = false
+ fallthrough
+ default:
+ p.printArg(a[argNum], verb)
+ argNum++
+ }
+ }
+
+ // Check for extra arguments unless the call accessed the arguments
+ // out of order, in which case it's too expensive to detect if they've all
+ // been used and arguably OK if they're not.
+ if !p.reordered && argNum < len(a) {
+ p.fmt.clearflags()
+ p.buf.writeString(extraString)
+ for i, arg := range a[argNum:] {
+ if i > 0 {
+ p.buf.writeString(commaSpaceString)
+ }
+ if arg == nil {
+ p.buf.writeString(nilAngleString)
+ } else {
+ p.buf.writeString(reflect.TypeOf(arg).String())
+ p.buf.writeByte('=')
+ p.printArg(arg, 'v')
+ }
+ }
+ p.buf.writeByte(')')
+ }
+}
+
+func (p *pp) doPrint(a []any) {
+ prevString := false
+ for argNum, arg := range a {
+ isString := arg != nil && reflect.TypeOf(arg).Kind() == reflect.String
+ // Add a space between two non-string arguments.
+ if argNum > 0 && !isString && !prevString {
+ p.buf.writeByte(' ')
+ }
+ p.printArg(arg, 'v')
+ prevString = isString
+ }
+}
+
+// doPrintln is like doPrint but always adds a space between arguments
+// and a newline after the last argument.
+func (p *pp) doPrintln(a []any) {
+ for argNum, arg := range a {
+ if argNum > 0 {
+ p.buf.writeByte(' ')
+ }
+ p.printArg(arg, 'v')
+ }
+ p.buf.writeByte('\n')
+}
diff --git a/go/src/fmt/scan.go b/go/src/fmt/scan.go
new file mode 100644
index 0000000000000000000000000000000000000000..d8c7d263e059271bc591e5c29260601e4325145f
--- /dev/null
+++ b/go/src/fmt/scan.go
@@ -0,0 +1,1238 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package fmt
+
+import (
+ "errors"
+ "io"
+ "math"
+ "os"
+ "reflect"
+ "strconv"
+ "sync"
+ "unicode/utf8"
+)
+
+// ScanState represents the scanner state passed to custom scanners.
+// Scanners may do rune-at-a-time scanning or ask the ScanState
+// to discover the next space-delimited token.
+type ScanState interface {
+ // ReadRune reads the next rune (Unicode code point) from the input.
+ // If invoked during Scanln, Fscanln, or Sscanln, ReadRune() will
+ // return EOF after returning the first '\n' or when reading beyond
+ // the specified width.
+ ReadRune() (r rune, size int, err error)
+ // UnreadRune causes the next call to ReadRune to return the same rune.
+ UnreadRune() error
+ // SkipSpace skips space in the input. Newlines are treated appropriately
+ // for the operation being performed; see the package documentation
+ // for more information.
+ SkipSpace()
+ // Token skips space in the input if skipSpace is true, then returns the
+ // run of Unicode code points c satisfying f(c). If f is nil,
+ // !unicode.IsSpace(c) is used; that is, the token will hold non-space
+ // characters. Newlines are treated appropriately for the operation being
+ // performed; see the package documentation for more information.
+ // The returned slice points to shared data that may be overwritten
+ // by the next call to Token, a call to a Scan function using the ScanState
+ // as input, or when the calling Scan method returns.
+ Token(skipSpace bool, f func(rune) bool) (token []byte, err error)
+ // Width returns the value of the width option and whether it has been set.
+ // The unit is Unicode code points.
+ Width() (wid int, ok bool)
+ // Because ReadRune is implemented by the interface, Read should never be
+ // called by the scanning routines and a valid implementation of
+ // ScanState may choose always to return an error from Read.
+ Read(buf []byte) (n int, err error)
+}
+
+// Scanner is implemented by any value that has a Scan method, which scans
+// the input for the representation of a value and stores the result in the
+// receiver, which must be a pointer to be useful. The Scan method is called
+// for any argument to [Scan], [Scanf], or [Scanln] that implements it.
+type Scanner interface {
+ Scan(state ScanState, verb rune) error
+}
+
+// Scan scans text read from standard input, storing successive
+// space-separated values into successive arguments. Newlines count
+// as space. It returns the number of items successfully scanned.
+// If that is less than the number of arguments, err will report why.
+func Scan(a ...any) (n int, err error) {
+ return Fscan(os.Stdin, a...)
+}
+
+// Scanln is similar to [Scan], but stops scanning at a newline and
+// after the final item there must be a newline or EOF.
+func Scanln(a ...any) (n int, err error) {
+ return Fscanln(os.Stdin, a...)
+}
+
+// Scanf scans text read from standard input, storing successive
+// space-separated values into successive arguments as determined by
+// the format. It returns the number of items successfully scanned.
+// If that is less than the number of arguments, err will report why.
+// Newlines in the input must match newlines in the format.
+// The one exception: the verb %c always scans the next rune in the
+// input, even if it is a space (or tab etc.) or newline.
+func Scanf(format string, a ...any) (n int, err error) {
+ return Fscanf(os.Stdin, format, a...)
+}
+
+type stringReader string
+
+func (r *stringReader) Read(b []byte) (n int, err error) {
+ n = copy(b, *r)
+ *r = (*r)[n:]
+ if n == 0 {
+ err = io.EOF
+ }
+ return
+}
+
+// Sscan scans the argument string, storing successive space-separated
+// values into successive arguments. Newlines count as space. It
+// returns the number of items successfully scanned. If that is less
+// than the number of arguments, err will report why.
+func Sscan(str string, a ...any) (n int, err error) {
+ return Fscan((*stringReader)(&str), a...)
+}
+
+// Sscanln is similar to [Sscan], but stops scanning at a newline and
+// after the final item there must be a newline or EOF.
+func Sscanln(str string, a ...any) (n int, err error) {
+ return Fscanln((*stringReader)(&str), a...)
+}
+
+// Sscanf scans the argument string, storing successive space-separated
+// values into successive arguments as determined by the format. It
+// returns the number of items successfully parsed.
+// Newlines in the input must match newlines in the format.
+func Sscanf(str string, format string, a ...any) (n int, err error) {
+ return Fscanf((*stringReader)(&str), format, a...)
+}
+
+// Fscan scans text read from r, storing successive space-separated
+// values into successive arguments. Newlines count as space. It
+// returns the number of items successfully scanned. If that is less
+// than the number of arguments, err will report why.
+func Fscan(r io.Reader, a ...any) (n int, err error) {
+ s, old := newScanState(r, true, false)
+ n, err = s.doScan(a)
+ s.free(old)
+ return
+}
+
+// Fscanln is similar to [Fscan], but stops scanning at a newline and
+// after the final item there must be a newline or EOF.
+func Fscanln(r io.Reader, a ...any) (n int, err error) {
+ s, old := newScanState(r, false, true)
+ n, err = s.doScan(a)
+ s.free(old)
+ return
+}
+
+// Fscanf scans text read from r, storing successive space-separated
+// values into successive arguments as determined by the format. It
+// returns the number of items successfully parsed.
+// Newlines in the input must match newlines in the format.
+func Fscanf(r io.Reader, format string, a ...any) (n int, err error) {
+ s, old := newScanState(r, false, false)
+ n, err = s.doScanf(format, a)
+ s.free(old)
+ return
+}
+
+// scanError represents an error generated by the scanning software.
+// It's used as a unique signature to identify such errors when recovering.
+type scanError struct {
+ err error
+}
+
+const eof = -1
+
+// ss is the internal implementation of ScanState.
+type ss struct {
+ rs io.RuneScanner // where to read input
+ buf buffer // token accumulator
+ count int // runes consumed so far.
+ atEOF bool // already read EOF
+ ssave
+}
+
+// ssave holds the parts of ss that need to be
+// saved and restored on recursive scans.
+type ssave struct {
+ validSave bool // is or was a part of an actual ss.
+ nlIsEnd bool // whether newline terminates scan
+ nlIsSpace bool // whether newline counts as white space
+ argLimit int // max value of ss.count for this arg; argLimit <= limit
+ limit int // max value of ss.count.
+ maxWid int // width of this arg.
+}
+
+// The Read method is only in ScanState so that ScanState
+// satisfies io.Reader. It will never be called when used as
+// intended, so there is no need to make it actually work.
+func (s *ss) Read(buf []byte) (n int, err error) {
+ return 0, errors.New("ScanState's Read should not be called. Use ReadRune")
+}
+
+func (s *ss) ReadRune() (r rune, size int, err error) {
+ if s.atEOF || s.count >= s.argLimit {
+ err = io.EOF
+ return
+ }
+
+ r, size, err = s.rs.ReadRune()
+ if err == nil {
+ s.count++
+ if s.nlIsEnd && r == '\n' {
+ s.atEOF = true
+ }
+ } else if err == io.EOF {
+ s.atEOF = true
+ }
+ return
+}
+
+func (s *ss) Width() (wid int, ok bool) {
+ if s.maxWid == hugeWid {
+ return 0, false
+ }
+ return s.maxWid, true
+}
+
+// The public method returns an error; this private one panics.
+// If getRune reaches EOF, the return value is EOF (-1).
+func (s *ss) getRune() (r rune) {
+ r, _, err := s.ReadRune()
+ if err != nil {
+ if err == io.EOF {
+ return eof
+ }
+ s.error(err)
+ }
+ return
+}
+
+// mustReadRune turns io.EOF into a panic(io.ErrUnexpectedEOF).
+// It is called in cases such as string scanning where an EOF is a
+// syntax error.
+func (s *ss) mustReadRune() (r rune) {
+ r = s.getRune()
+ if r == eof {
+ s.error(io.ErrUnexpectedEOF)
+ }
+ return
+}
+
+func (s *ss) UnreadRune() error {
+ s.rs.UnreadRune()
+ s.atEOF = false
+ s.count--
+ return nil
+}
+
+func (s *ss) error(err error) {
+ panic(scanError{err})
+}
+
+func (s *ss) errorString(err string) {
+ panic(scanError{errors.New(err)})
+}
+
+func (s *ss) Token(skipSpace bool, f func(rune) bool) (tok []byte, err error) {
+ defer func() {
+ if e := recover(); e != nil {
+ if se, ok := e.(scanError); ok {
+ err = se.err
+ } else {
+ panic(e)
+ }
+ }
+ }()
+ if f == nil {
+ f = notSpace
+ }
+ s.buf = s.buf[:0]
+ tok = s.token(skipSpace, f)
+ return
+}
+
+// space is a copy of the unicode.White_Space ranges,
+// to avoid depending on package unicode.
+var space = [][2]uint16{
+ {0x0009, 0x000d},
+ {0x0020, 0x0020},
+ {0x0085, 0x0085},
+ {0x00a0, 0x00a0},
+ {0x1680, 0x1680},
+ {0x2000, 0x200a},
+ {0x2028, 0x2029},
+ {0x202f, 0x202f},
+ {0x205f, 0x205f},
+ {0x3000, 0x3000},
+}
+
+func isSpace(r rune) bool {
+ if r >= 1<<16 {
+ return false
+ }
+ rx := uint16(r)
+ for _, rng := range space {
+ if rx < rng[0] {
+ return false
+ }
+ if rx <= rng[1] {
+ return true
+ }
+ }
+ return false
+}
+
+// notSpace is the default scanning function used in Token.
+func notSpace(r rune) bool {
+ return !isSpace(r)
+}
+
+// readRune is a structure to enable reading UTF-8 encoded code points
+// from an io.Reader. It is used if the Reader given to the scanner does
+// not already implement io.RuneScanner.
+type readRune struct {
+ reader io.Reader
+ buf [utf8.UTFMax]byte // used only inside ReadRune
+ pending int // number of bytes in pendBuf; only >0 for bad UTF-8
+ pendBuf [utf8.UTFMax]byte // bytes left over
+ peekRune rune // if >=0 next rune; when <0 is ^(previous Rune)
+}
+
+// readByte returns the next byte from the input, which may be
+// left over from a previous read if the UTF-8 was ill-formed.
+func (r *readRune) readByte() (b byte, err error) {
+ if r.pending > 0 {
+ b = r.pendBuf[0]
+ copy(r.pendBuf[0:], r.pendBuf[1:])
+ r.pending--
+ return
+ }
+ n, err := io.ReadFull(r.reader, r.pendBuf[:1])
+ if n != 1 {
+ return 0, err
+ }
+ return r.pendBuf[0], err
+}
+
+// ReadRune returns the next UTF-8 encoded code point from the
+// io.Reader inside r.
+func (r *readRune) ReadRune() (rr rune, size int, err error) {
+ if r.peekRune >= 0 {
+ rr = r.peekRune
+ r.peekRune = ^r.peekRune
+ size = utf8.RuneLen(rr)
+ return
+ }
+ r.buf[0], err = r.readByte()
+ if err != nil {
+ return
+ }
+ if r.buf[0] < utf8.RuneSelf { // fast check for common ASCII case
+ rr = rune(r.buf[0])
+ size = 1 // Known to be 1.
+ // Flip the bits of the rune so it's available to UnreadRune.
+ r.peekRune = ^rr
+ return
+ }
+ var n int
+ for n = 1; !utf8.FullRune(r.buf[:n]); n++ {
+ r.buf[n], err = r.readByte()
+ if err != nil {
+ if err == io.EOF {
+ err = nil
+ break
+ }
+ return
+ }
+ }
+ rr, size = utf8.DecodeRune(r.buf[:n])
+ if size < n { // an error, save the bytes for the next read
+ copy(r.pendBuf[r.pending:], r.buf[size:n])
+ r.pending += n - size
+ }
+ // Flip the bits of the rune so it's available to UnreadRune.
+ r.peekRune = ^rr
+ return
+}
+
+func (r *readRune) UnreadRune() error {
+ if r.peekRune >= 0 {
+ return errors.New("fmt: scanning called UnreadRune with no rune available")
+ }
+ // Reverse bit flip of previously read rune to obtain valid >=0 state.
+ r.peekRune = ^r.peekRune
+ return nil
+}
+
+var ssFree = sync.Pool{
+ New: func() any { return new(ss) },
+}
+
+// newScanState allocates a new ss struct or grab a cached one.
+func newScanState(r io.Reader, nlIsSpace, nlIsEnd bool) (s *ss, old ssave) {
+ s = ssFree.Get().(*ss)
+ if rs, ok := r.(io.RuneScanner); ok {
+ s.rs = rs
+ } else {
+ s.rs = &readRune{reader: r, peekRune: -1}
+ }
+ s.nlIsSpace = nlIsSpace
+ s.nlIsEnd = nlIsEnd
+ s.atEOF = false
+ s.limit = hugeWid
+ s.argLimit = hugeWid
+ s.maxWid = hugeWid
+ s.validSave = true
+ s.count = 0
+ return
+}
+
+// free saves used ss structs in ssFree; avoid an allocation per invocation.
+func (s *ss) free(old ssave) {
+ // If it was used recursively, just restore the old state.
+ if old.validSave {
+ s.ssave = old
+ return
+ }
+ // Don't hold on to ss structs with large buffers.
+ if cap(s.buf) > 1024 {
+ return
+ }
+ s.buf = s.buf[:0]
+ s.rs = nil
+ ssFree.Put(s)
+}
+
+// SkipSpace provides Scan methods the ability to skip space and newline
+// characters in keeping with the current scanning mode set by format strings
+// and [Scan]/[Scanln].
+func (s *ss) SkipSpace() {
+ for {
+ r := s.getRune()
+ if r == eof {
+ return
+ }
+ if r == '\r' && s.peek("\n") {
+ continue
+ }
+ if r == '\n' {
+ if s.nlIsSpace {
+ continue
+ }
+ s.errorString("unexpected newline")
+ return
+ }
+ if !isSpace(r) {
+ s.UnreadRune()
+ break
+ }
+ }
+}
+
+// token returns the next space-delimited string from the input. It
+// skips white space. For Scanln, it stops at newlines. For Scan,
+// newlines are treated as spaces.
+func (s *ss) token(skipSpace bool, f func(rune) bool) []byte {
+ if skipSpace {
+ s.SkipSpace()
+ }
+ // read until white space or newline
+ for {
+ r := s.getRune()
+ if r == eof {
+ break
+ }
+ if !f(r) {
+ s.UnreadRune()
+ break
+ }
+ s.buf.writeRune(r)
+ }
+ return s.buf
+}
+
+var errComplex = errors.New("syntax error scanning complex number")
+var errBool = errors.New("syntax error scanning boolean")
+
+func indexRune(s string, r rune) int {
+ for i, c := range s {
+ if c == r {
+ return i
+ }
+ }
+ return -1
+}
+
+// consume reads the next rune in the input and reports whether it is in the ok string.
+// If accept is true, it puts the character into the input token.
+func (s *ss) consume(ok string, accept bool) bool {
+ r := s.getRune()
+ if r == eof {
+ return false
+ }
+ if indexRune(ok, r) >= 0 {
+ if accept {
+ s.buf.writeRune(r)
+ }
+ return true
+ }
+ if r != eof && accept {
+ s.UnreadRune()
+ }
+ return false
+}
+
+// peek reports whether the next character is in the ok string, without consuming it.
+func (s *ss) peek(ok string) bool {
+ r := s.getRune()
+ if r != eof {
+ s.UnreadRune()
+ }
+ return indexRune(ok, r) >= 0
+}
+
+func (s *ss) notEOF() {
+ // Guarantee there is data to be read.
+ if r := s.getRune(); r == eof {
+ panic(io.EOF)
+ }
+ s.UnreadRune()
+}
+
+// accept checks the next rune in the input. If it's a byte (sic) in the string, it puts it in the
+// buffer and returns true. Otherwise it return false.
+func (s *ss) accept(ok string) bool {
+ return s.consume(ok, true)
+}
+
+// okVerb verifies that the verb is present in the list, setting s.err appropriately if not.
+func (s *ss) okVerb(verb rune, okVerbs, typ string) bool {
+ for _, v := range okVerbs {
+ if v == verb {
+ return true
+ }
+ }
+ s.errorString("bad verb '%" + string(verb) + "' for " + typ)
+ return false
+}
+
+// scanBool returns the value of the boolean represented by the next token.
+func (s *ss) scanBool(verb rune) bool {
+ s.SkipSpace()
+ s.notEOF()
+ if !s.okVerb(verb, "tv", "boolean") {
+ return false
+ }
+ // Syntax-checking a boolean is annoying. We're not fastidious about case.
+ switch s.getRune() {
+ case '0':
+ return false
+ case '1':
+ return true
+ case 't', 'T':
+ if s.accept("rR") && (!s.accept("uU") || !s.accept("eE")) {
+ s.error(errBool)
+ }
+ return true
+ case 'f', 'F':
+ if s.accept("aA") && (!s.accept("lL") || !s.accept("sS") || !s.accept("eE")) {
+ s.error(errBool)
+ }
+ return false
+ }
+ return false
+}
+
+// Numerical elements
+const (
+ binaryDigits = "01"
+ octalDigits = "01234567"
+ decimalDigits = "0123456789"
+ hexadecimalDigits = "0123456789aAbBcCdDeEfF"
+ sign = "+-"
+ period = "."
+ exponent = "eEpP"
+)
+
+// getBase returns the numeric base represented by the verb and its digit string.
+func (s *ss) getBase(verb rune) (base int, digits string) {
+ s.okVerb(verb, "bdoUxXv", "integer") // sets s.err
+ base = 10
+ digits = decimalDigits
+ switch verb {
+ case 'b':
+ base = 2
+ digits = binaryDigits
+ case 'o':
+ base = 8
+ digits = octalDigits
+ case 'x', 'X', 'U':
+ base = 16
+ digits = hexadecimalDigits
+ }
+ return
+}
+
+// scanNumber returns the numerical string with specified digits starting here.
+func (s *ss) scanNumber(digits string, haveDigits bool) string {
+ if !haveDigits {
+ s.notEOF()
+ if !s.accept(digits) {
+ s.errorString("expected integer")
+ }
+ }
+ for s.accept(digits) {
+ }
+ return string(s.buf)
+}
+
+// scanRune returns the next rune value in the input.
+func (s *ss) scanRune(bitSize int) int64 {
+ s.notEOF()
+ r := s.getRune()
+ n := uint(bitSize)
+ x := (int64(r) << (64 - n)) >> (64 - n)
+ if x != int64(r) {
+ s.errorString("overflow on character value " + string(r))
+ }
+ return int64(r)
+}
+
+// scanBasePrefix reports whether the integer begins with a base prefix
+// and returns the base, digit string, and whether a zero was found.
+// It is called only if the verb is %v.
+func (s *ss) scanBasePrefix() (base int, digits string, zeroFound bool) {
+ if !s.peek("0") {
+ return 0, decimalDigits + "_", false
+ }
+ s.accept("0")
+ // Special cases for 0, 0b, 0o, 0x.
+ switch {
+ case s.peek("bB"):
+ s.consume("bB", true)
+ return 0, binaryDigits + "_", true
+ case s.peek("oO"):
+ s.consume("oO", true)
+ return 0, octalDigits + "_", true
+ case s.peek("xX"):
+ s.consume("xX", true)
+ return 0, hexadecimalDigits + "_", true
+ default:
+ return 0, octalDigits + "_", true
+ }
+}
+
+// scanInt returns the value of the integer represented by the next
+// token, checking for overflow. Any error is stored in s.err.
+func (s *ss) scanInt(verb rune, bitSize int) int64 {
+ if verb == 'c' {
+ return s.scanRune(bitSize)
+ }
+ s.SkipSpace()
+ s.notEOF()
+ base, digits := s.getBase(verb)
+ haveDigits := false
+ if verb == 'U' {
+ if !s.consume("U", false) || !s.consume("+", false) {
+ s.errorString("bad unicode format ")
+ }
+ } else {
+ s.accept(sign) // If there's a sign, it will be left in the token buffer.
+ if verb == 'v' {
+ base, digits, haveDigits = s.scanBasePrefix()
+ }
+ }
+ tok := s.scanNumber(digits, haveDigits)
+ i, err := strconv.ParseInt(tok, base, 64)
+ if err != nil {
+ s.error(err)
+ }
+ n := uint(bitSize)
+ x := (i << (64 - n)) >> (64 - n)
+ if x != i {
+ s.errorString("integer overflow on token " + tok)
+ }
+ return i
+}
+
+// scanUint returns the value of the unsigned integer represented
+// by the next token, checking for overflow. Any error is stored in s.err.
+func (s *ss) scanUint(verb rune, bitSize int) uint64 {
+ if verb == 'c' {
+ return uint64(s.scanRune(bitSize))
+ }
+ s.SkipSpace()
+ s.notEOF()
+ base, digits := s.getBase(verb)
+ haveDigits := false
+ if verb == 'U' {
+ if !s.consume("U", false) || !s.consume("+", false) {
+ s.errorString("bad unicode format ")
+ }
+ } else if verb == 'v' {
+ base, digits, haveDigits = s.scanBasePrefix()
+ }
+ tok := s.scanNumber(digits, haveDigits)
+ i, err := strconv.ParseUint(tok, base, 64)
+ if err != nil {
+ s.error(err)
+ }
+ n := uint(bitSize)
+ x := (i << (64 - n)) >> (64 - n)
+ if x != i {
+ s.errorString("unsigned integer overflow on token " + tok)
+ }
+ return i
+}
+
+// floatToken returns the floating-point number starting here, no longer than swid
+// if the width is specified. It's not rigorous about syntax because it doesn't check that
+// we have at least some digits, but Atof will do that.
+func (s *ss) floatToken() string {
+ s.buf = s.buf[:0]
+ // NaN?
+ if s.accept("nN") && s.accept("aA") && s.accept("nN") {
+ return string(s.buf)
+ }
+ // leading sign?
+ s.accept(sign)
+ // Inf?
+ if s.accept("iI") && s.accept("nN") && s.accept("fF") {
+ return string(s.buf)
+ }
+ digits := decimalDigits + "_"
+ exp := exponent
+ if s.accept("0") && s.accept("xX") {
+ digits = hexadecimalDigits + "_"
+ exp = "pP"
+ }
+ // digits?
+ for s.accept(digits) {
+ }
+ // decimal point?
+ if s.accept(period) {
+ // fraction?
+ for s.accept(digits) {
+ }
+ }
+ // exponent?
+ if s.accept(exp) {
+ // leading sign?
+ s.accept(sign)
+ // digits?
+ for s.accept(decimalDigits + "_") {
+ }
+ }
+ return string(s.buf)
+}
+
+// complexTokens returns the real and imaginary parts of the complex number starting here.
+// The number might be parenthesized and has the format (N+Ni) where N is a floating-point
+// number and there are no spaces within.
+func (s *ss) complexTokens() (real, imag string) {
+ // TODO: accept N and Ni independently?
+ parens := s.accept("(")
+ real = s.floatToken()
+ s.buf = s.buf[:0]
+ // Must now have a sign.
+ if !s.accept("+-") {
+ s.error(errComplex)
+ }
+ // Sign is now in buffer
+ imagSign := string(s.buf)
+ imag = s.floatToken()
+ if !s.accept("i") {
+ s.error(errComplex)
+ }
+ if parens && !s.accept(")") {
+ s.error(errComplex)
+ }
+ return real, imagSign + imag
+}
+
+func hasX(s string) bool {
+ for i := 0; i < len(s); i++ {
+ if s[i] == 'x' || s[i] == 'X' {
+ return true
+ }
+ }
+ return false
+}
+
+// convertFloat converts the string to a float64value.
+func (s *ss) convertFloat(str string, n int) float64 {
+ // strconv.ParseFloat will handle "+0x1.fp+2",
+ // but we have to implement our non-standard
+ // decimal+binary exponent mix (1.2p4) ourselves.
+ if p := indexRune(str, 'p'); p >= 0 && !hasX(str) {
+ // Atof doesn't handle power-of-2 exponents,
+ // but they're easy to evaluate.
+ f, err := strconv.ParseFloat(str[:p], n)
+ if err != nil {
+ // Put full string into error.
+ if e, ok := err.(*strconv.NumError); ok {
+ e.Num = str
+ }
+ s.error(err)
+ }
+ m, err := strconv.Atoi(str[p+1:])
+ if err != nil {
+ // Put full string into error.
+ if e, ok := err.(*strconv.NumError); ok {
+ e.Num = str
+ }
+ s.error(err)
+ }
+ return math.Ldexp(f, m)
+ }
+ f, err := strconv.ParseFloat(str, n)
+ if err != nil {
+ s.error(err)
+ }
+ return f
+}
+
+// scanComplex converts the next token to a complex128 value.
+// The atof argument is a type-specific reader for the underlying type.
+// If we're reading complex64, atof will parse float32s and convert them
+// to float64's to avoid reproducing this code for each complex type.
+func (s *ss) scanComplex(verb rune, n int) complex128 {
+ if !s.okVerb(verb, floatVerbs, "complex") {
+ return 0
+ }
+ s.SkipSpace()
+ s.notEOF()
+ sreal, simag := s.complexTokens()
+ real := s.convertFloat(sreal, n/2)
+ imag := s.convertFloat(simag, n/2)
+ return complex(real, imag)
+}
+
+// convertString returns the string represented by the next input characters.
+// The format of the input is determined by the verb.
+func (s *ss) convertString(verb rune) (str string) {
+ if !s.okVerb(verb, "svqxX", "string") {
+ return ""
+ }
+ s.SkipSpace()
+ s.notEOF()
+ switch verb {
+ case 'q':
+ str = s.quotedString()
+ case 'x', 'X':
+ str = s.hexString()
+ default:
+ str = string(s.token(true, notSpace)) // %s and %v just return the next word
+ }
+ return
+}
+
+// quotedString returns the double- or back-quoted string represented by the next input characters.
+func (s *ss) quotedString() string {
+ s.notEOF()
+ quote := s.getRune()
+ switch quote {
+ case '`':
+ // Back-quoted: Anything goes until EOF or back quote.
+ for {
+ r := s.mustReadRune()
+ if r == quote {
+ break
+ }
+ s.buf.writeRune(r)
+ }
+ return string(s.buf)
+ case '"':
+ // Double-quoted: Include the quotes and let strconv.Unquote do the backslash escapes.
+ s.buf.writeByte('"')
+ for {
+ r := s.mustReadRune()
+ s.buf.writeRune(r)
+ if r == '\\' {
+ // In a legal backslash escape, no matter how long, only the character
+ // immediately after the escape can itself be a backslash or quote.
+ // Thus we only need to protect the first character after the backslash.
+ s.buf.writeRune(s.mustReadRune())
+ } else if r == '"' {
+ break
+ }
+ }
+ result, err := strconv.Unquote(string(s.buf))
+ if err != nil {
+ s.error(err)
+ }
+ return result
+ default:
+ s.errorString("expected quoted string")
+ }
+ return ""
+}
+
+// hexDigit returns the value of the hexadecimal digit.
+func hexDigit(d rune) (int, bool) {
+ digit := int(d)
+ switch digit {
+ case '0', '1', '2', '3', '4', '5', '6', '7', '8', '9':
+ return digit - '0', true
+ case 'a', 'b', 'c', 'd', 'e', 'f':
+ return 10 + digit - 'a', true
+ case 'A', 'B', 'C', 'D', 'E', 'F':
+ return 10 + digit - 'A', true
+ }
+ return -1, false
+}
+
+// hexByte returns the next hex-encoded (two-character) byte from the input.
+// It returns ok==false if the next bytes in the input do not encode a hex byte.
+// If the first byte is hex and the second is not, processing stops.
+func (s *ss) hexByte() (b byte, ok bool) {
+ rune1 := s.getRune()
+ if rune1 == eof {
+ return
+ }
+ value1, ok := hexDigit(rune1)
+ if !ok {
+ s.UnreadRune()
+ return
+ }
+ value2, ok := hexDigit(s.mustReadRune())
+ if !ok {
+ s.errorString("illegal hex digit")
+ return
+ }
+ return byte(value1<<4 | value2), true
+}
+
+// hexString returns the space-delimited hexpair-encoded string.
+func (s *ss) hexString() string {
+ s.notEOF()
+ for {
+ b, ok := s.hexByte()
+ if !ok {
+ break
+ }
+ s.buf.writeByte(b)
+ }
+ if len(s.buf) == 0 {
+ s.errorString("no hex data for %x string")
+ return ""
+ }
+ return string(s.buf)
+}
+
+const (
+ floatVerbs = "beEfFgGv"
+
+ hugeWid = 1 << 30
+
+ intBits = 32 << (^uint(0) >> 63)
+ uintptrBits = 32 << (^uintptr(0) >> 63)
+)
+
+// scanPercent scans a literal percent character.
+func (s *ss) scanPercent() {
+ s.SkipSpace()
+ s.notEOF()
+ if !s.accept("%") {
+ s.errorString("missing literal %")
+ }
+}
+
+// scanOne scans a single value, deriving the scanner from the type of the argument.
+func (s *ss) scanOne(verb rune, arg any) {
+ s.buf = s.buf[:0]
+ var err error
+ // If the parameter has its own Scan method, use that.
+ if v, ok := arg.(Scanner); ok {
+ err = v.Scan(s, verb)
+ if err != nil {
+ if err == io.EOF {
+ err = io.ErrUnexpectedEOF
+ }
+ s.error(err)
+ }
+ return
+ }
+
+ switch v := arg.(type) {
+ case *bool:
+ *v = s.scanBool(verb)
+ case *complex64:
+ *v = complex64(s.scanComplex(verb, 64))
+ case *complex128:
+ *v = s.scanComplex(verb, 128)
+ case *int:
+ *v = int(s.scanInt(verb, intBits))
+ case *int8:
+ *v = int8(s.scanInt(verb, 8))
+ case *int16:
+ *v = int16(s.scanInt(verb, 16))
+ case *int32:
+ *v = int32(s.scanInt(verb, 32))
+ case *int64:
+ *v = s.scanInt(verb, 64)
+ case *uint:
+ *v = uint(s.scanUint(verb, intBits))
+ case *uint8:
+ *v = uint8(s.scanUint(verb, 8))
+ case *uint16:
+ *v = uint16(s.scanUint(verb, 16))
+ case *uint32:
+ *v = uint32(s.scanUint(verb, 32))
+ case *uint64:
+ *v = s.scanUint(verb, 64)
+ case *uintptr:
+ *v = uintptr(s.scanUint(verb, uintptrBits))
+ // Floats are tricky because you want to scan in the precision of the result, not
+ // scan in high precision and convert, in order to preserve the correct error condition.
+ case *float32:
+ if s.okVerb(verb, floatVerbs, "float32") {
+ s.SkipSpace()
+ s.notEOF()
+ *v = float32(s.convertFloat(s.floatToken(), 32))
+ }
+ case *float64:
+ if s.okVerb(verb, floatVerbs, "float64") {
+ s.SkipSpace()
+ s.notEOF()
+ *v = s.convertFloat(s.floatToken(), 64)
+ }
+ case *string:
+ *v = s.convertString(verb)
+ case *[]byte:
+ // We scan to string and convert so we get a copy of the data.
+ // If we scanned to bytes, the slice would point at the buffer.
+ *v = []byte(s.convertString(verb))
+ default:
+ val := reflect.ValueOf(v)
+ ptr := val
+ if ptr.Kind() != reflect.Pointer {
+ s.errorString("type not a pointer: " + val.Type().String())
+ return
+ }
+ switch v := ptr.Elem(); v.Kind() {
+ case reflect.Bool:
+ v.SetBool(s.scanBool(verb))
+ case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+ v.SetInt(s.scanInt(verb, v.Type().Bits()))
+ case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+ v.SetUint(s.scanUint(verb, v.Type().Bits()))
+ case reflect.String:
+ v.SetString(s.convertString(verb))
+ case reflect.Slice:
+ // For now, can only handle (renamed) []byte.
+ typ := v.Type()
+ if typ.Elem().Kind() != reflect.Uint8 {
+ s.errorString("can't scan type: " + val.Type().String())
+ }
+ str := s.convertString(verb)
+ v.Set(reflect.MakeSlice(typ, len(str), len(str)))
+ for i := 0; i < len(str); i++ {
+ v.Index(i).SetUint(uint64(str[i]))
+ }
+ case reflect.Float32, reflect.Float64:
+ s.SkipSpace()
+ s.notEOF()
+ v.SetFloat(s.convertFloat(s.floatToken(), v.Type().Bits()))
+ case reflect.Complex64, reflect.Complex128:
+ v.SetComplex(s.scanComplex(verb, v.Type().Bits()))
+ default:
+ s.errorString("can't scan type: " + val.Type().String())
+ }
+ }
+}
+
+// errorHandler turns local panics into error returns.
+func errorHandler(errp *error) {
+ if e := recover(); e != nil {
+ if se, ok := e.(scanError); ok { // catch local error
+ *errp = se.err
+ } else if eof, ok := e.(error); ok && eof == io.EOF { // out of input
+ *errp = eof
+ } else {
+ panic(e)
+ }
+ }
+}
+
+// doScan does the real work for scanning without a format string.
+func (s *ss) doScan(a []any) (numProcessed int, err error) {
+ defer errorHandler(&err)
+ for _, arg := range a {
+ s.scanOne('v', arg)
+ numProcessed++
+ }
+ // Check for newline (or EOF) if required (Scanln etc.).
+ if s.nlIsEnd {
+ for {
+ r := s.getRune()
+ if r == '\n' || r == eof {
+ break
+ }
+ if !isSpace(r) {
+ s.errorString("expected newline")
+ break
+ }
+ }
+ }
+ return
+}
+
+// advance determines whether the next characters in the input match
+// those of the format. It returns the number of bytes (sic) consumed
+// in the format. All runs of space characters in either input or
+// format behave as a single space. Newlines are special, though:
+// newlines in the format must match those in the input and vice versa.
+// This routine also handles the %% case. If the return value is zero,
+// either format starts with a % (with no following %) or the input
+// is empty. If it is negative, the input did not match the string.
+func (s *ss) advance(format string) (i int) {
+ for i < len(format) {
+ fmtc, w := utf8.DecodeRuneInString(format[i:])
+
+ // Space processing.
+ // In the rest of this comment "space" means spaces other than newline.
+ // Newline in the format matches input of zero or more spaces and then newline or end-of-input.
+ // Spaces in the format before the newline are collapsed into the newline.
+ // Spaces in the format after the newline match zero or more spaces after the corresponding input newline.
+ // Other spaces in the format match input of one or more spaces or end-of-input.
+ if isSpace(fmtc) {
+ newlines := 0
+ trailingSpace := false
+ for isSpace(fmtc) && i < len(format) {
+ if fmtc == '\n' {
+ newlines++
+ trailingSpace = false
+ } else {
+ trailingSpace = true
+ }
+ i += w
+ fmtc, w = utf8.DecodeRuneInString(format[i:])
+ }
+ for j := 0; j < newlines; j++ {
+ inputc := s.getRune()
+ for isSpace(inputc) && inputc != '\n' {
+ inputc = s.getRune()
+ }
+ if inputc != '\n' && inputc != eof {
+ s.errorString("newline in format does not match input")
+ }
+ }
+ if trailingSpace {
+ inputc := s.getRune()
+ if newlines == 0 {
+ // If the trailing space stood alone (did not follow a newline),
+ // it must find at least one space to consume.
+ if !isSpace(inputc) && inputc != eof {
+ s.errorString("expected space in input to match format")
+ }
+ if inputc == '\n' {
+ s.errorString("newline in input does not match format")
+ }
+ }
+ for isSpace(inputc) && inputc != '\n' {
+ inputc = s.getRune()
+ }
+ if inputc != eof {
+ s.UnreadRune()
+ }
+ }
+ continue
+ }
+
+ // Verbs.
+ if fmtc == '%' {
+ // % at end of string is an error.
+ if i+w == len(format) {
+ s.errorString("missing verb: % at end of format string")
+ }
+ // %% acts like a real percent
+ nextc, _ := utf8.DecodeRuneInString(format[i+w:]) // will not match % if string is empty
+ if nextc != '%' {
+ return
+ }
+ i += w // skip the first %
+ }
+
+ // Literals.
+ inputc := s.mustReadRune()
+ if fmtc != inputc {
+ s.UnreadRune()
+ return -1
+ }
+ i += w
+ }
+ return
+}
+
+// doScanf does the real work when scanning with a format string.
+// At the moment, it handles only pointers to basic types.
+func (s *ss) doScanf(format string, a []any) (numProcessed int, err error) {
+ defer errorHandler(&err)
+ end := len(format) - 1
+ // We process one item per non-trivial format
+ for i := 0; i <= end; {
+ w := s.advance(format[i:])
+ if w > 0 {
+ i += w
+ continue
+ }
+ // Either we failed to advance, we have a percent character, or we ran out of input.
+ if format[i] != '%' {
+ // Can't advance format. Why not?
+ if w < 0 {
+ s.errorString("input does not match format")
+ }
+ // Otherwise at EOF; "too many operands" error handled below
+ break
+ }
+ i++ // % is one byte
+
+ // do we have 20 (width)?
+ var widPresent bool
+ s.maxWid, widPresent, i = parsenum(format, i, end)
+ if !widPresent {
+ s.maxWid = hugeWid
+ }
+
+ c, w := utf8.DecodeRuneInString(format[i:])
+ i += w
+
+ if c != 'c' {
+ s.SkipSpace()
+ }
+ if c == '%' {
+ s.scanPercent()
+ continue // Do not consume an argument.
+ }
+ s.argLimit = s.limit
+ if f := s.count + s.maxWid; f < s.argLimit {
+ s.argLimit = f
+ }
+
+ if numProcessed >= len(a) { // out of operands
+ s.errorString("too few operands for format '%" + format[i-w:] + "'")
+ break
+ }
+ arg := a[numProcessed]
+
+ s.scanOne(c, arg)
+ numProcessed++
+ s.argLimit = s.limit
+ }
+ if numProcessed < len(a) {
+ s.errorString("too many operands")
+ }
+ return
+}
diff --git a/go/src/fmt/scan_test.go b/go/src/fmt/scan_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..ff9e4f30ca8c873f89457c4f8fa2fcf62453a9a6
--- /dev/null
+++ b/go/src/fmt/scan_test.go
@@ -0,0 +1,1334 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package fmt_test
+
+import (
+ "bufio"
+ "bytes"
+ "errors"
+ . "fmt"
+ "io"
+ "math"
+ "reflect"
+ "regexp"
+ "strings"
+ "testing"
+ "testing/iotest"
+ "unicode/utf8"
+)
+
+type ScanTest struct {
+ text string
+ in any
+ out any
+}
+
+type ScanfTest struct {
+ format string
+ text string
+ in any
+ out any
+}
+
+type ScanfMultiTest struct {
+ format string
+ text string
+ in []any
+ out []any
+ err string
+}
+
+var (
+ boolVal bool
+ intVal int
+ int8Val int8
+ int16Val int16
+ int32Val int32
+ int64Val int64
+ uintVal uint
+ uint8Val uint8
+ uint16Val uint16
+ uint32Val uint32
+ uint64Val uint64
+ uintptrVal uintptr
+ float32Val float32
+ float64Val float64
+ stringVal string
+ bytesVal []byte
+ runeVal rune
+ complex64Val complex64
+ complex128Val complex128
+ renamedBoolVal renamedBool
+ renamedIntVal renamedInt
+ renamedInt8Val renamedInt8
+ renamedInt16Val renamedInt16
+ renamedInt32Val renamedInt32
+ renamedInt64Val renamedInt64
+ renamedUintVal renamedUint
+ renamedUint8Val renamedUint8
+ renamedUint16Val renamedUint16
+ renamedUint32Val renamedUint32
+ renamedUint64Val renamedUint64
+ renamedUintptrVal renamedUintptr
+ renamedStringVal renamedString
+ renamedBytesVal renamedBytes
+ renamedFloat32Val renamedFloat32
+ renamedFloat64Val renamedFloat64
+ renamedComplex64Val renamedComplex64
+ renamedComplex128Val renamedComplex128
+)
+
+// Xs accepts any non-empty run of the verb character
+type Xs string
+
+func (x *Xs) Scan(state ScanState, verb rune) error {
+ tok, err := state.Token(true, func(r rune) bool { return r == verb })
+ if err != nil {
+ return err
+ }
+ s := string(tok)
+ if !regexp.MustCompile("^" + string(verb) + "+$").MatchString(s) {
+ return errors.New("syntax error for xs")
+ }
+ *x = Xs(s)
+ return nil
+}
+
+var xVal Xs
+
+// IntString accepts an integer followed immediately by a string.
+// It tests the embedding of a scan within a scan.
+type IntString struct {
+ i int
+ s string
+}
+
+func (s *IntString) Scan(state ScanState, verb rune) error {
+ if _, err := Fscan(state, &s.i); err != nil {
+ return err
+ }
+
+ tok, err := state.Token(true, nil)
+ if err != nil {
+ return err
+ }
+ s.s = string(tok)
+ return nil
+}
+
+var intStringVal IntString
+
+var scanTests = []ScanTest{
+ // Basic types
+ {"T\n", &boolVal, true}, // boolean test vals toggle to be sure they are written
+ {"F\n", &boolVal, false}, // restored to zero value
+ {"21\n", &intVal, 21},
+ {"2_1\n", &intVal, 21},
+ {"0\n", &intVal, 0},
+ {"000\n", &intVal, 0},
+ {"0x10\n", &intVal, 0x10},
+ {"0x_1_0\n", &intVal, 0x10},
+ {"-0x10\n", &intVal, -0x10},
+ {"0377\n", &intVal, 0377},
+ {"0_3_7_7\n", &intVal, 0377},
+ {"0o377\n", &intVal, 0377},
+ {"0o_3_7_7\n", &intVal, 0377},
+ {"-0377\n", &intVal, -0377},
+ {"-0o377\n", &intVal, -0377},
+ {"0\n", &uintVal, uint(0)},
+ {"000\n", &uintVal, uint(0)},
+ {"0x10\n", &uintVal, uint(0x10)},
+ {"0377\n", &uintVal, uint(0377)},
+ {"22\n", &int8Val, int8(22)},
+ {"23\n", &int16Val, int16(23)},
+ {"24\n", &int32Val, int32(24)},
+ {"25\n", &int64Val, int64(25)},
+ {"127\n", &int8Val, int8(127)},
+ {"-21\n", &intVal, -21},
+ {"-22\n", &int8Val, int8(-22)},
+ {"-23\n", &int16Val, int16(-23)},
+ {"-24\n", &int32Val, int32(-24)},
+ {"-25\n", &int64Val, int64(-25)},
+ {"-128\n", &int8Val, int8(-128)},
+ {"+21\n", &intVal, +21},
+ {"+22\n", &int8Val, int8(+22)},
+ {"+23\n", &int16Val, int16(+23)},
+ {"+24\n", &int32Val, int32(+24)},
+ {"+25\n", &int64Val, int64(+25)},
+ {"+127\n", &int8Val, int8(+127)},
+ {"26\n", &uintVal, uint(26)},
+ {"27\n", &uint8Val, uint8(27)},
+ {"28\n", &uint16Val, uint16(28)},
+ {"29\n", &uint32Val, uint32(29)},
+ {"30\n", &uint64Val, uint64(30)},
+ {"31\n", &uintptrVal, uintptr(31)},
+ {"255\n", &uint8Val, uint8(255)},
+ {"32767\n", &int16Val, int16(32767)},
+ {"2.3\n", &float64Val, 2.3},
+ {"2.3e1\n", &float32Val, float32(2.3e1)},
+ {"2.3e2\n", &float64Val, 2.3e2},
+ {"2.3p2\n", &float64Val, 2.3 * 4},
+ {"2.3p+2\n", &float64Val, 2.3 * 4},
+ {"2.3p+66\n", &float64Val, 2.3 * (1 << 66)},
+ {"2.3p-66\n", &float64Val, 2.3 / (1 << 66)},
+ {"0x2.3p-66\n", &float64Val, float64(0x23) / (1 << 70)},
+ {"2_3.4_5\n", &float64Val, 23.45},
+ {"2.35\n", &stringVal, "2.35"},
+ {"2345678\n", &bytesVal, []byte("2345678")},
+ {"(3.4e1-2i)\n", &complex128Val, 3.4e1 - 2i},
+ {"-3.45e1-3i\n", &complex64Val, complex64(-3.45e1 - 3i)},
+ {"-.45e1-1e2i\n", &complex128Val, complex128(-.45e1 - 100i)},
+ {"-.4_5e1-1E2i\n", &complex128Val, complex128(-.45e1 - 100i)},
+ {"0x1.0p1+0x1.0P2i\n", &complex128Val, complex128(2 + 4i)},
+ {"-0x1p1-0x1p2i\n", &complex128Val, complex128(-2 - 4i)},
+ {"-0x1ep-1-0x1p2i\n", &complex128Val, complex128(-15 - 4i)},
+ {"-0x1_Ep-1-0x1p0_2i\n", &complex128Val, complex128(-15 - 4i)},
+ {"hello\n", &stringVal, "hello"},
+
+ // Carriage-return followed by newline. (We treat \r\n as \n always.)
+ {"hello\r\n", &stringVal, "hello"},
+ {"27\r\n", &uint8Val, uint8(27)},
+
+ // Renamed types
+ {"true\n", &renamedBoolVal, renamedBool(true)},
+ {"F\n", &renamedBoolVal, renamedBool(false)},
+ {"101\n", &renamedIntVal, renamedInt(101)},
+ {"102\n", &renamedIntVal, renamedInt(102)},
+ {"103\n", &renamedUintVal, renamedUint(103)},
+ {"104\n", &renamedUintVal, renamedUint(104)},
+ {"105\n", &renamedInt8Val, renamedInt8(105)},
+ {"106\n", &renamedInt16Val, renamedInt16(106)},
+ {"107\n", &renamedInt32Val, renamedInt32(107)},
+ {"108\n", &renamedInt64Val, renamedInt64(108)},
+ {"109\n", &renamedUint8Val, renamedUint8(109)},
+ {"110\n", &renamedUint16Val, renamedUint16(110)},
+ {"111\n", &renamedUint32Val, renamedUint32(111)},
+ {"112\n", &renamedUint64Val, renamedUint64(112)},
+ {"113\n", &renamedUintptrVal, renamedUintptr(113)},
+ {"114\n", &renamedStringVal, renamedString("114")},
+ {"115\n", &renamedBytesVal, renamedBytes([]byte("115"))},
+
+ // Custom scanners.
+ {" vvv ", &xVal, Xs("vvv")},
+ {" 1234hello", &intStringVal, IntString{1234, "hello"}},
+
+ // Fixed bugs
+ {"2147483648\n", &int64Val, int64(2147483648)}, // was: integer overflow
+}
+
+var scanfTests = []ScanfTest{
+ {"%v", "TRUE\n", &boolVal, true},
+ {"%t", "false\n", &boolVal, false},
+ {"%v", "-71\n", &intVal, -71},
+ {"%v", "-7_1\n", &intVal, -71},
+ {"%v", "0b111\n", &intVal, 7},
+ {"%v", "0b_1_1_1\n", &intVal, 7},
+ {"%v", "0377\n", &intVal, 0377},
+ {"%v", "0_3_7_7\n", &intVal, 0377},
+ {"%v", "0o377\n", &intVal, 0377},
+ {"%v", "0o_3_7_7\n", &intVal, 0377},
+ {"%v", "0x44\n", &intVal, 0x44},
+ {"%v", "0x_4_4\n", &intVal, 0x44},
+ {"%d", "72\n", &intVal, 72},
+ {"%c", "a\n", &runeVal, 'a'},
+ {"%c", "\u5072\n", &runeVal, '\u5072'},
+ {"%c", "\u1234\n", &runeVal, '\u1234'},
+ {"%d", "73\n", &int8Val, int8(73)},
+ {"%d", "+74\n", &int16Val, int16(74)},
+ {"%d", "75\n", &int32Val, int32(75)},
+ {"%d", "76\n", &int64Val, int64(76)},
+ {"%b", "1001001\n", &intVal, 73},
+ {"%o", "075\n", &intVal, 075},
+ {"%x", "a75\n", &intVal, 0xa75},
+ {"%v", "71\n", &uintVal, uint(71)},
+ {"%d", "72\n", &uintVal, uint(72)},
+ {"%d", "7_2\n", &uintVal, uint(7)}, // only %v takes underscores
+ {"%d", "73\n", &uint8Val, uint8(73)},
+ {"%d", "74\n", &uint16Val, uint16(74)},
+ {"%d", "75\n", &uint32Val, uint32(75)},
+ {"%d", "76\n", &uint64Val, uint64(76)},
+ {"%d", "77\n", &uintptrVal, uintptr(77)},
+ {"%b", "1001001\n", &uintVal, uint(73)},
+ {"%b", "100_1001\n", &uintVal, uint(4)},
+ {"%o", "075\n", &uintVal, uint(075)},
+ {"%o", "07_5\n", &uintVal, uint(07)}, // only %v takes underscores
+ {"%x", "a75\n", &uintVal, uint(0xa75)},
+ {"%x", "A75\n", &uintVal, uint(0xa75)},
+ {"%x", "A7_5\n", &uintVal, uint(0xa7)}, // only %v takes underscores
+ {"%U", "U+1234\n", &intVal, int(0x1234)},
+ {"%U", "U+4567\n", &uintVal, uint(0x4567)},
+
+ {"%e", "2.3\n", &float64Val, 2.3},
+ {"%E", "2.3e1\n", &float32Val, float32(2.3e1)},
+ {"%f", "2.3e2\n", &float64Val, 2.3e2},
+ {"%g", "2.3p2\n", &float64Val, 2.3 * 4},
+ {"%G", "2.3p+2\n", &float64Val, 2.3 * 4},
+ {"%v", "2.3p+66\n", &float64Val, 2.3 * (1 << 66)},
+ {"%f", "2.3p-66\n", &float64Val, 2.3 / (1 << 66)},
+ {"%G", "0x2.3p-66\n", &float64Val, float64(0x23) / (1 << 70)},
+ {"%E", "2_3.4_5\n", &float64Val, 23.45},
+
+ // Strings
+ {"%s", "using-%s\n", &stringVal, "using-%s"},
+ {"%x", "7573696e672d2578\n", &stringVal, "using-%x"},
+ {"%X", "7573696E672D2558\n", &stringVal, "using-%X"},
+ {"%q", `"quoted\twith\\do\u0075bl\x65s"` + "\n", &stringVal, "quoted\twith\\doubles"},
+ {"%q", "`quoted with backs`\n", &stringVal, "quoted with backs"},
+
+ // Byte slices
+ {"%s", "bytes-%s\n", &bytesVal, []byte("bytes-%s")},
+ {"%x", "62797465732d2578\n", &bytesVal, []byte("bytes-%x")},
+ {"%X", "62797465732D2558\n", &bytesVal, []byte("bytes-%X")},
+ {"%q", `"bytes\rwith\vdo\u0075bl\x65s"` + "\n", &bytesVal, []byte("bytes\rwith\vdoubles")},
+ {"%q", "`bytes with backs`\n", &bytesVal, []byte("bytes with backs")},
+
+ // Renamed types
+ {"%v\n", "true\n", &renamedBoolVal, renamedBool(true)},
+ {"%t\n", "F\n", &renamedBoolVal, renamedBool(false)},
+ {"%v", "101\n", &renamedIntVal, renamedInt(101)},
+ {"%c", "\u0101\n", &renamedIntVal, renamedInt('\u0101')},
+ {"%o", "0146\n", &renamedIntVal, renamedInt(102)},
+ {"%v", "103\n", &renamedUintVal, renamedUint(103)},
+ {"%d", "104\n", &renamedUintVal, renamedUint(104)},
+ {"%d", "105\n", &renamedInt8Val, renamedInt8(105)},
+ {"%d", "106\n", &renamedInt16Val, renamedInt16(106)},
+ {"%d", "107\n", &renamedInt32Val, renamedInt32(107)},
+ {"%d", "108\n", &renamedInt64Val, renamedInt64(108)},
+ {"%x", "6D\n", &renamedUint8Val, renamedUint8(109)},
+ {"%o", "0156\n", &renamedUint16Val, renamedUint16(110)},
+ {"%d", "111\n", &renamedUint32Val, renamedUint32(111)},
+ {"%d", "112\n", &renamedUint64Val, renamedUint64(112)},
+ {"%d", "113\n", &renamedUintptrVal, renamedUintptr(113)},
+ {"%s", "114\n", &renamedStringVal, renamedString("114")},
+ {"%q", "\"1155\"\n", &renamedBytesVal, renamedBytes([]byte("1155"))},
+ {"%g", "116e1\n", &renamedFloat32Val, renamedFloat32(116e1)},
+ {"%g", "-11.7e+1", &renamedFloat64Val, renamedFloat64(-11.7e+1)},
+ {"%g", "11+6e1i\n", &renamedComplex64Val, renamedComplex64(11 + 6e1i)},
+ {"%g", "-11.+7e+1i", &renamedComplex128Val, renamedComplex128(-11. + 7e+1i)},
+
+ // Interesting formats
+ {"here is\tthe value:%d", "here is the\tvalue:118\n", &intVal, 118},
+ {"%% %%:%d", "% %:119\n", &intVal, 119},
+ {"%d%%", "42%", &intVal, 42}, // %% at end of string.
+
+ // Corner cases
+ {"%x", "FFFFFFFF\n", &uint32Val, uint32(0xFFFFFFFF)},
+
+ // Custom scanner.
+ {"%s", " sss ", &xVal, Xs("sss")},
+ {"%2s", "sssss", &xVal, Xs("ss")},
+
+ // Fixed bugs
+ {"%d\n", "27\n", &intVal, 27}, // ok
+ {"%d\n", "28 \n", &intVal, 28}, // was: "unexpected newline"
+ {"%v", "0", &intVal, 0}, // was: "EOF"; 0 was taken as base prefix and not counted.
+ {"%v", "0", &uintVal, uint(0)}, // was: "EOF"; 0 was taken as base prefix and not counted.
+ {"%c", " ", &uintVal, uint(' ')}, // %c must accept a blank.
+ {"%c", "\t", &uintVal, uint('\t')}, // %c must accept any space.
+ {"%c", "\n", &uintVal, uint('\n')}, // %c must accept any space.
+ {"%d%%", "23%\n", &uintVal, uint(23)}, // %% matches literal %.
+ {"%%%d", "%23\n", &uintVal, uint(23)}, // %% matches literal %.
+
+ // space handling
+ {"%d", "27", &intVal, 27},
+ {"%d", "27 ", &intVal, 27},
+ {"%d", " 27", &intVal, 27},
+ {"%d", " 27 ", &intVal, 27},
+
+ {"X%d", "X27", &intVal, 27},
+ {"X%d", "X27 ", &intVal, 27},
+ {"X%d", "X 27", &intVal, 27},
+ {"X%d", "X 27 ", &intVal, 27},
+
+ {"X %d", "X27", &intVal, nil}, // expected space in input to match format
+ {"X %d", "X27 ", &intVal, nil}, // expected space in input to match format
+ {"X %d", "X 27", &intVal, 27},
+ {"X %d", "X 27 ", &intVal, 27},
+
+ {"%dX", "27X", &intVal, 27},
+ {"%dX", "27 X", &intVal, nil}, // input does not match format
+ {"%dX", " 27X", &intVal, 27},
+ {"%dX", " 27 X", &intVal, nil}, // input does not match format
+
+ {"%d X", "27X", &intVal, nil}, // expected space in input to match format
+ {"%d X", "27 X", &intVal, 27},
+ {"%d X", " 27X", &intVal, nil}, // expected space in input to match format
+ {"%d X", " 27 X", &intVal, 27},
+
+ {"X %d X", "X27X", &intVal, nil}, // expected space in input to match format
+ {"X %d X", "X27 X", &intVal, nil}, // expected space in input to match format
+ {"X %d X", "X 27X", &intVal, nil}, // expected space in input to match format
+ {"X %d X", "X 27 X", &intVal, 27},
+
+ {"X %s X", "X27X", &stringVal, nil}, // expected space in input to match format
+ {"X %s X", "X27 X", &stringVal, nil}, // expected space in input to match format
+ {"X %s X", "X 27X", &stringVal, nil}, // unexpected EOF
+ {"X %s X", "X 27 X", &stringVal, "27"},
+
+ {"X%sX", "X27X", &stringVal, nil}, // unexpected EOF
+ {"X%sX", "X27 X", &stringVal, nil}, // input does not match format
+ {"X%sX", "X 27X", &stringVal, nil}, // unexpected EOF
+ {"X%sX", "X 27 X", &stringVal, nil}, // input does not match format
+
+ {"X%s", "X27", &stringVal, "27"},
+ {"X%s", "X27 ", &stringVal, "27"},
+ {"X%s", "X 27", &stringVal, "27"},
+ {"X%s", "X 27 ", &stringVal, "27"},
+
+ {"X%dX", "X27X", &intVal, 27},
+ {"X%dX", "X27 X", &intVal, nil}, // input does not match format
+ {"X%dX", "X 27X", &intVal, 27},
+ {"X%dX", "X 27 X", &intVal, nil}, // input does not match format
+
+ {"X%dX", "X27X", &intVal, 27},
+ {"X%dX", "X27X ", &intVal, 27},
+ {"X%dX", " X27X", &intVal, nil}, // input does not match format
+ {"X%dX", " X27X ", &intVal, nil}, // input does not match format
+
+ {"X%dX\n", "X27X", &intVal, 27},
+ {"X%dX \n", "X27X ", &intVal, 27},
+ {"X%dX\n", "X27X\n", &intVal, 27},
+ {"X%dX\n", "X27X \n", &intVal, 27},
+
+ {"X%dX \n", "X27X", &intVal, 27},
+ {"X%dX \n", "X27X ", &intVal, 27},
+ {"X%dX \n", "X27X\n", &intVal, 27},
+ {"X%dX \n", "X27X \n", &intVal, 27},
+
+ {"X%c", "X\n", &runeVal, '\n'},
+ {"X%c", "X \n", &runeVal, ' '},
+ {"X %c", "X!", &runeVal, nil}, // expected space in input to match format
+ {"X %c", "X\n", &runeVal, nil}, // newline in input does not match format
+ {"X %c", "X !", &runeVal, '!'},
+ {"X %c", "X \n", &runeVal, '\n'},
+
+ {" X%dX", "X27X", &intVal, nil}, // expected space in input to match format
+ {" X%dX", "X27X ", &intVal, nil}, // expected space in input to match format
+ {" X%dX", " X27X", &intVal, 27},
+ {" X%dX", " X27X ", &intVal, 27},
+
+ {"X%dX ", "X27X", &intVal, 27},
+ {"X%dX ", "X27X ", &intVal, 27},
+ {"X%dX ", " X27X", &intVal, nil}, // input does not match format
+ {"X%dX ", " X27X ", &intVal, nil}, // input does not match format
+
+ {" X%dX ", "X27X", &intVal, nil}, // expected space in input to match format
+ {" X%dX ", "X27X ", &intVal, nil}, // expected space in input to match format
+ {" X%dX ", " X27X", &intVal, 27},
+ {" X%dX ", " X27X ", &intVal, 27},
+
+ {"%d\nX", "27\nX", &intVal, 27},
+ {"%dX\n X", "27X\n X", &intVal, 27},
+}
+
+var overflowTests = []ScanTest{
+ {"128", &int8Val, 0},
+ {"32768", &int16Val, 0},
+ {"-129", &int8Val, 0},
+ {"-32769", &int16Val, 0},
+ {"256", &uint8Val, 0},
+ {"65536", &uint16Val, 0},
+ {"1e100", &float32Val, 0},
+ {"1e500", &float64Val, 0},
+ {"(1e100+0i)", &complex64Val, 0},
+ {"(1+1e100i)", &complex64Val, 0},
+ {"(1-1e500i)", &complex128Val, 0},
+}
+
+var truth bool
+var i, j, k int
+var f float64
+var s, t string
+var c complex128
+var x, y Xs
+var z IntString
+var r1, r2, r3 rune
+
+var multiTests = []ScanfMultiTest{
+ {"", "", []any{}, []any{}, ""},
+ {"%d", "23", args(&i), args(23), ""},
+ {"%2s%3s", "22333", args(&s, &t), args("22", "333"), ""},
+ {"%2d%3d", "44555", args(&i, &j), args(44, 555), ""},
+ {"%2d.%3d", "66.777", args(&i, &j), args(66, 777), ""},
+ {"%d, %d", "23, 18", args(&i, &j), args(23, 18), ""},
+ {"%3d22%3d", "33322333", args(&i, &j), args(333, 333), ""},
+ {"%6vX=%3fY", "3+2iX=2.5Y", args(&c, &f), args((3 + 2i), 2.5), ""},
+ {"%d%s", "123abc", args(&i, &s), args(123, "abc"), ""},
+ {"%c%c%c", "2\u50c2X", args(&r1, &r2, &r3), args('2', '\u50c2', 'X'), ""},
+ {"%5s%d", " 1234567 ", args(&s, &i), args("12345", 67), ""},
+ {"%5s%d", " 12 34 567 ", args(&s, &i), args("12", 34), ""},
+
+ // Custom scanners.
+ {"%e%f", "eefffff", args(&x, &y), args(Xs("ee"), Xs("fffff")), ""},
+ {"%4v%s", "12abcd", args(&z, &s), args(IntString{12, "ab"}, "cd"), ""},
+
+ // Errors
+ {"%t", "23 18", args(&i), nil, "bad verb"},
+ {"%d %d %d", "23 18", args(&i, &j), args(23, 18), "too few operands"},
+ {"%d %d", "23 18 27", args(&i, &j, &k), args(23, 18), "too many operands"},
+ {"%c", "\u0100", args(&int8Val), nil, "overflow"},
+ {"X%d", "10X", args(&intVal), nil, "input does not match format"},
+ {"%d%", "42%", args(&intVal), args(42), "missing verb: % at end of format string"},
+ {"%d% ", "42%", args(&intVal), args(42), "too few operands for format '% '"}, // Slightly odd error, but correct.
+ {"%%%d", "xxx 42", args(&intVal), args(42), "missing literal %"},
+ {"%%%d", "x42", args(&intVal), args(42), "missing literal %"},
+ {"%%%d", "42", args(&intVal), args(42), "missing literal %"},
+
+ // Bad UTF-8: should see every byte.
+ {"%c%c%c", "\xc2X\xc2", args(&r1, &r2, &r3), args(utf8.RuneError, 'X', utf8.RuneError), ""},
+
+ // Fixed bugs
+ {"%v%v", "FALSE23", args(&truth, &i), args(false, 23), ""},
+}
+
+var readers = []struct {
+ name string
+ f func(string) io.Reader
+}{
+ {"StringReader", func(s string) io.Reader {
+ return strings.NewReader(s)
+ }},
+ {"ReaderOnly", func(s string) io.Reader {
+ return struct{ io.Reader }{strings.NewReader(s)}
+ }},
+ {"OneByteReader", func(s string) io.Reader {
+ return iotest.OneByteReader(strings.NewReader(s))
+ }},
+ {"DataErrReader", func(s string) io.Reader {
+ return iotest.DataErrReader(strings.NewReader(s))
+ }},
+}
+
+func testScan(t *testing.T, f func(string) io.Reader, scan func(r io.Reader, a ...any) (int, error)) {
+ for _, test := range scanTests {
+ r := f(test.text)
+ n, err := scan(r, test.in)
+ if err != nil {
+ m := ""
+ if n > 0 {
+ m = Sprintf(" (%d fields ok)", n)
+ }
+ t.Errorf("got error scanning %q: %s%s", test.text, err, m)
+ continue
+ }
+ if n != 1 {
+ t.Errorf("count error on entry %q: got %d", test.text, n)
+ continue
+ }
+ // The incoming value may be a pointer
+ v := reflect.ValueOf(test.in)
+ if p := v; p.Kind() == reflect.Pointer {
+ v = p.Elem()
+ }
+ val := v.Interface()
+ if !reflect.DeepEqual(val, test.out) {
+ t.Errorf("scanning %q: expected %#v got %#v, type %T", test.text, test.out, val, val)
+ }
+ }
+}
+
+func TestScan(t *testing.T) {
+ for _, r := range readers {
+ t.Run(r.name, func(t *testing.T) {
+ testScan(t, r.f, Fscan)
+ })
+ }
+}
+
+func TestScanln(t *testing.T) {
+ for _, r := range readers {
+ t.Run(r.name, func(t *testing.T) {
+ testScan(t, r.f, Fscanln)
+ })
+ }
+}
+
+func TestScanf(t *testing.T) {
+ for _, test := range scanfTests {
+ n, err := Sscanf(test.text, test.format, test.in)
+ if err != nil {
+ if test.out != nil {
+ t.Errorf("Sscanf(%q, %q): unexpected error: %v", test.text, test.format, err)
+ }
+ continue
+ }
+ if test.out == nil {
+ t.Errorf("Sscanf(%q, %q): unexpected success", test.text, test.format)
+ continue
+ }
+ if n != 1 {
+ t.Errorf("Sscanf(%q, %q): parsed %d field, want 1", test.text, test.format, n)
+ continue
+ }
+ // The incoming value may be a pointer
+ v := reflect.ValueOf(test.in)
+ if p := v; p.Kind() == reflect.Pointer {
+ v = p.Elem()
+ }
+ val := v.Interface()
+ if !reflect.DeepEqual(val, test.out) {
+ t.Errorf("Sscanf(%q, %q): parsed value %T(%#v), want %T(%#v)", test.text, test.format, val, val, test.out, test.out)
+ }
+ }
+}
+
+func TestScanOverflow(t *testing.T) {
+ // different machines and different types report errors with different strings.
+ re := regexp.MustCompile("overflow|too large|out of range|not representable")
+ for _, test := range overflowTests {
+ _, err := Sscan(test.text, test.in)
+ if err == nil {
+ t.Errorf("expected overflow scanning %q", test.text)
+ continue
+ }
+ if !re.MatchString(err.Error()) {
+ t.Errorf("expected overflow error scanning %q: %s", test.text, err)
+ }
+ }
+}
+
+func verifyNaN(str string, t *testing.T) {
+ var f float64
+ var f32 float32
+ var f64 float64
+ text := str + " " + str + " " + str
+ n, err := Fscan(strings.NewReader(text), &f, &f32, &f64)
+ if err != nil {
+ t.Errorf("got error scanning %q: %s", text, err)
+ }
+ if n != 3 {
+ t.Errorf("count error scanning %q: got %d", text, n)
+ }
+ if !math.IsNaN(float64(f)) || !math.IsNaN(float64(f32)) || !math.IsNaN(f64) {
+ t.Errorf("didn't get NaNs scanning %q: got %g %g %g", text, f, f32, f64)
+ }
+}
+
+func TestNaN(t *testing.T) {
+ for _, s := range []string{"nan", "NAN", "NaN"} {
+ verifyNaN(s, t)
+ }
+}
+
+func verifyInf(str string, t *testing.T) {
+ var f float64
+ var f32 float32
+ var f64 float64
+ text := str + " " + str + " " + str
+ n, err := Fscan(strings.NewReader(text), &f, &f32, &f64)
+ if err != nil {
+ t.Errorf("got error scanning %q: %s", text, err)
+ }
+ if n != 3 {
+ t.Errorf("count error scanning %q: got %d", text, n)
+ }
+ sign := 1
+ if str[0] == '-' {
+ sign = -1
+ }
+ if !math.IsInf(float64(f), sign) || !math.IsInf(float64(f32), sign) || !math.IsInf(f64, sign) {
+ t.Errorf("didn't get right Infs scanning %q: got %g %g %g", text, f, f32, f64)
+ }
+}
+
+func TestInf(t *testing.T) {
+ for _, s := range []string{"inf", "+inf", "-inf", "INF", "-INF", "+INF", "Inf", "-Inf", "+Inf"} {
+ verifyInf(s, t)
+ }
+}
+
+func testScanfMulti(t *testing.T, f func(string) io.Reader) {
+ sliceType := reflect.TypeOf(make([]any, 1))
+ for _, test := range multiTests {
+ r := f(test.text)
+ n, err := Fscanf(r, test.format, test.in...)
+ if err != nil {
+ if test.err == "" {
+ t.Errorf("got error scanning (%q, %q): %q", test.format, test.text, err)
+ } else if !strings.Contains(err.Error(), test.err) {
+ t.Errorf("got wrong error scanning (%q, %q): %q; expected %q", test.format, test.text, err, test.err)
+ }
+ continue
+ }
+ if test.err != "" {
+ t.Errorf("expected error %q error scanning (%q, %q)", test.err, test.format, test.text)
+ }
+ if n != len(test.out) {
+ t.Errorf("count error on entry (%q, %q): expected %d got %d", test.format, test.text, len(test.out), n)
+ continue
+ }
+ // Convert the slice of pointers into a slice of values
+ resultVal := reflect.MakeSlice(sliceType, n, n)
+ for i := 0; i < n; i++ {
+ v := reflect.ValueOf(test.in[i]).Elem()
+ resultVal.Index(i).Set(v)
+ }
+ result := resultVal.Interface()
+ if !reflect.DeepEqual(result, test.out) {
+ t.Errorf("scanning (%q, %q): expected %#v got %#v", test.format, test.text, test.out, result)
+ }
+ }
+}
+
+func TestScanfMulti(t *testing.T) {
+ for _, r := range readers {
+ t.Run(r.name, func(t *testing.T) {
+ testScanfMulti(t, r.f)
+ })
+ }
+}
+
+func TestScanMultiple(t *testing.T) {
+ var a int
+ var s string
+ n, err := Sscan("123abc", &a, &s)
+ if n != 2 {
+ t.Errorf("Sscan count error: expected 2: got %d", n)
+ }
+ if err != nil {
+ t.Errorf("Sscan expected no error; got %s", err)
+ }
+ if a != 123 || s != "abc" {
+ t.Errorf("Sscan wrong values: got (%d %q) expected (123 \"abc\")", a, s)
+ }
+ n, err = Sscan("asdf", &s, &a)
+ if n != 1 {
+ t.Errorf("Sscan count error: expected 1: got %d", n)
+ }
+ if err == nil {
+ t.Errorf("Sscan expected error; got none: %s", err)
+ }
+ if s != "asdf" {
+ t.Errorf("Sscan wrong values: got %q expected \"asdf\"", s)
+ }
+}
+
+// Empty strings are not valid input when scanning a string.
+func TestScanEmpty(t *testing.T) {
+ var s1, s2 string
+ n, err := Sscan("abc", &s1, &s2)
+ if n != 1 {
+ t.Errorf("Sscan count error: expected 1: got %d", n)
+ }
+ if err == nil {
+ t.Error("Sscan expected error; got none")
+ }
+ if s1 != "abc" {
+ t.Errorf("Sscan wrong values: got %q expected \"abc\"", s1)
+ }
+ n, err = Sscan("", &s1, &s2)
+ if n != 0 {
+ t.Errorf("Sscan count error: expected 0: got %d", n)
+ }
+ if err == nil {
+ t.Error("Sscan expected error; got none")
+ }
+ // Quoted empty string is OK.
+ n, err = Sscanf(`""`, "%q", &s1)
+ if n != 1 {
+ t.Errorf("Sscanf count error: expected 1: got %d", n)
+ }
+ if err != nil {
+ t.Errorf("Sscanf expected no error with quoted string; got %s", err)
+ }
+}
+
+func TestScanNotPointer(t *testing.T) {
+ r := strings.NewReader("1")
+ var a int
+ _, err := Fscan(r, a)
+ if err == nil {
+ t.Error("expected error scanning non-pointer")
+ } else if !strings.Contains(err.Error(), "pointer") {
+ t.Errorf("expected pointer error scanning non-pointer, got: %s", err)
+ }
+}
+
+func TestScanlnNoNewline(t *testing.T) {
+ var a int
+ _, err := Sscanln("1 x\n", &a)
+ if err == nil {
+ t.Error("expected error scanning string missing newline")
+ } else if !strings.Contains(err.Error(), "newline") {
+ t.Errorf("expected newline error scanning string missing newline, got: %s", err)
+ }
+}
+
+func TestScanlnWithMiddleNewline(t *testing.T) {
+ r := strings.NewReader("123\n456\n")
+ var a, b int
+ _, err := Fscanln(r, &a, &b)
+ if err == nil {
+ t.Error("expected error scanning string with extra newline")
+ } else if !strings.Contains(err.Error(), "newline") {
+ t.Errorf("expected newline error scanning string with extra newline, got: %s", err)
+ }
+}
+
+// eofCounter is a special Reader that counts reads at end of file.
+type eofCounter struct {
+ reader *strings.Reader
+ eofCount int
+}
+
+func (ec *eofCounter) Read(b []byte) (n int, err error) {
+ n, err = ec.reader.Read(b)
+ if n == 0 {
+ ec.eofCount++
+ }
+ return
+}
+
+// TestEOF verifies that when we scan, we see at most EOF once per call to a
+// Scan function, and then only when it's really an EOF.
+func TestEOF(t *testing.T) {
+ ec := &eofCounter{strings.NewReader("123\n"), 0}
+ var a int
+ n, err := Fscanln(ec, &a)
+ if err != nil {
+ t.Error("unexpected error", err)
+ }
+ if n != 1 {
+ t.Error("expected to scan one item, got", n)
+ }
+ if ec.eofCount != 0 {
+ t.Error("expected zero EOFs", ec.eofCount)
+ ec.eofCount = 0 // reset for next test
+ }
+ n, err = Fscanln(ec, &a)
+ if err == nil {
+ t.Error("expected error scanning empty string")
+ }
+ if n != 0 {
+ t.Error("expected to scan zero items, got", n)
+ }
+ if ec.eofCount != 1 {
+ t.Error("expected one EOF, got", ec.eofCount)
+ }
+}
+
+// TestEOFAtEndOfInput verifies that we see an EOF error if we run out of input.
+// This was a buglet: we used to get "expected integer".
+func TestEOFAtEndOfInput(t *testing.T) {
+ var i, j int
+ n, err := Sscanf("23", "%d %d", &i, &j)
+ if n != 1 || i != 23 {
+ t.Errorf("Sscanf expected one value of 23; got %d %d", n, i)
+ }
+ if err != io.EOF {
+ t.Errorf("Sscanf expected EOF; got %q", err)
+ }
+ n, err = Sscan("234", &i, &j)
+ if n != 1 || i != 234 {
+ t.Errorf("Sscan expected one value of 234; got %d %d", n, i)
+ }
+ if err != io.EOF {
+ t.Errorf("Sscan expected EOF; got %q", err)
+ }
+ // Trailing space is tougher.
+ n, err = Sscan("234 ", &i, &j)
+ if n != 1 || i != 234 {
+ t.Errorf("Sscan expected one value of 234; got %d %d", n, i)
+ }
+ if err != io.EOF {
+ t.Errorf("Sscan expected EOF; got %q", err)
+ }
+}
+
+var eofTests = []struct {
+ format string
+ v any
+}{
+ {"%s", &stringVal},
+ {"%q", &stringVal},
+ {"%x", &stringVal},
+ {"%v", &stringVal},
+ {"%v", &bytesVal},
+ {"%v", &intVal},
+ {"%v", &uintVal},
+ {"%v", &boolVal},
+ {"%v", &float32Val},
+ {"%v", &complex64Val},
+ {"%v", &renamedStringVal},
+ {"%v", &renamedBytesVal},
+ {"%v", &renamedIntVal},
+ {"%v", &renamedUintVal},
+ {"%v", &renamedBoolVal},
+ {"%v", &renamedFloat32Val},
+ {"%v", &renamedComplex64Val},
+}
+
+func TestEOFAllTypes(t *testing.T) {
+ for i, test := range eofTests {
+ if _, err := Sscanf("", test.format, test.v); err != io.EOF {
+ t.Errorf("#%d: %s %T not eof on empty string: %s", i, test.format, test.v, err)
+ }
+ if _, err := Sscanf(" ", test.format, test.v); err != io.EOF {
+ t.Errorf("#%d: %s %T not eof on trailing blanks: %s", i, test.format, test.v, err)
+ }
+ }
+}
+
+// TestUnreadRuneWithBufio verifies that, at least when using bufio, successive
+// calls to Fscan do not lose runes.
+func TestUnreadRuneWithBufio(t *testing.T) {
+ r := bufio.NewReader(strings.NewReader("123αb"))
+ var i int
+ var a string
+ n, err := Fscanf(r, "%d", &i)
+ if n != 1 || err != nil {
+ t.Errorf("reading int expected one item, no errors; got %d %q", n, err)
+ }
+ if i != 123 {
+ t.Errorf("expected 123; got %d", i)
+ }
+ n, err = Fscanf(r, "%s", &a)
+ if n != 1 || err != nil {
+ t.Errorf("reading string expected one item, no errors; got %d %q", n, err)
+ }
+ if a != "αb" {
+ t.Errorf("expected αb; got %q", a)
+ }
+}
+
+type TwoLines string
+
+// Scan attempts to read two lines into the object. Scanln should prevent this
+// because it stops at newline; Scan and Scanf should be fine.
+func (t *TwoLines) Scan(state ScanState, verb rune) error {
+ chars := make([]rune, 0, 100)
+ for nlCount := 0; nlCount < 2; {
+ c, _, err := state.ReadRune()
+ if err != nil {
+ return err
+ }
+ chars = append(chars, c)
+ if c == '\n' {
+ nlCount++
+ }
+ }
+ *t = TwoLines(string(chars))
+ return nil
+}
+
+func TestMultiLine(t *testing.T) {
+ input := "abc\ndef\n"
+ // Sscan should work
+ var tscan TwoLines
+ n, err := Sscan(input, &tscan)
+ if n != 1 {
+ t.Errorf("Sscan: expected 1 item; got %d", n)
+ }
+ if err != nil {
+ t.Errorf("Sscan: expected no error; got %s", err)
+ }
+ if string(tscan) != input {
+ t.Errorf("Sscan: expected %q; got %q", input, tscan)
+ }
+ // Sscanf should work
+ var tscanf TwoLines
+ n, err = Sscanf(input, "%s", &tscanf)
+ if n != 1 {
+ t.Errorf("Sscanf: expected 1 item; got %d", n)
+ }
+ if err != nil {
+ t.Errorf("Sscanf: expected no error; got %s", err)
+ }
+ if string(tscanf) != input {
+ t.Errorf("Sscanf: expected %q; got %q", input, tscanf)
+ }
+ // Sscanln should not work
+ var tscanln TwoLines
+ n, err = Sscanln(input, &tscanln)
+ if n != 0 {
+ t.Errorf("Sscanln: expected 0 items; got %d: %q", n, tscanln)
+ }
+ if err == nil {
+ t.Error("Sscanln: expected error; got none")
+ } else if err != io.ErrUnexpectedEOF {
+ t.Errorf("Sscanln: expected io.ErrUnexpectedEOF (ha!); got %s", err)
+ }
+}
+
+// TestLineByLineFscanf tests that Fscanf does not read past newline. Issue
+// 3481.
+func TestLineByLineFscanf(t *testing.T) {
+ r := struct{ io.Reader }{strings.NewReader("1\n2\n")}
+ var i, j int
+ n, err := Fscanf(r, "%v\n", &i)
+ if n != 1 || err != nil {
+ t.Fatalf("first read: %d %q", n, err)
+ }
+ n, err = Fscanf(r, "%v\n", &j)
+ if n != 1 || err != nil {
+ t.Fatalf("second read: %d %q", n, err)
+ }
+ if i != 1 || j != 2 {
+ t.Errorf("wrong values; wanted 1 2 got %d %d", i, j)
+ }
+}
+
+// TestScanStateCount verifies the correct byte count is returned. Issue 8512.
+
+// runeScanner implements the Scanner interface for TestScanStateCount.
+type runeScanner struct {
+ rune rune
+ size int
+}
+
+func (rs *runeScanner) Scan(state ScanState, verb rune) error {
+ r, size, err := state.ReadRune()
+ rs.rune = r
+ rs.size = size
+ return err
+}
+
+func TestScanStateCount(t *testing.T) {
+ var a, b, c runeScanner
+ n, err := Sscanf("12➂", "%c%c%c", &a, &b, &c)
+ if err != nil {
+ t.Fatal(err)
+ }
+ if n != 3 {
+ t.Fatalf("expected 3 items consumed, got %d", n)
+ }
+ if a.rune != '1' || b.rune != '2' || c.rune != '➂' {
+ t.Errorf("bad scan rune: %q %q %q should be '1' '2' '➂'", a.rune, b.rune, c.rune)
+ }
+ if a.size != 1 || b.size != 1 || c.size != 3 {
+ t.Errorf("bad scan size: %d %d %d should be 1 1 3", a.size, b.size, c.size)
+ }
+}
+
+// RecursiveInt accepts a string matching %d.%d.%d....
+// and parses it into a linked list.
+// It allows us to benchmark recursive descent style scanners.
+type RecursiveInt struct {
+ i int
+ next *RecursiveInt
+}
+
+func (r *RecursiveInt) Scan(state ScanState, verb rune) (err error) {
+ _, err = Fscan(state, &r.i)
+ if err != nil {
+ return
+ }
+ next := new(RecursiveInt)
+ _, err = Fscanf(state, ".%v", next)
+ if err != nil {
+ if err == io.ErrUnexpectedEOF {
+ err = nil
+ }
+ return
+ }
+ r.next = next
+ return
+}
+
+// scanInts performs the same scanning task as RecursiveInt.Scan
+// but without recurring through scanner, so we can compare
+// performance more directly.
+func scanInts(r *RecursiveInt, b *bytes.Buffer) (err error) {
+ r.next = nil
+ _, err = Fscan(b, &r.i)
+ if err != nil {
+ return
+ }
+ c, _, err := b.ReadRune()
+ if err != nil {
+ if err == io.EOF {
+ err = nil
+ }
+ return
+ }
+ if c != '.' {
+ return
+ }
+ next := new(RecursiveInt)
+ err = scanInts(next, b)
+ if err == nil {
+ r.next = next
+ }
+ return
+}
+
+func makeInts(n int) []byte {
+ var buf bytes.Buffer
+ Fprintf(&buf, "1")
+ for i := 1; i < n; i++ {
+ Fprintf(&buf, ".%d", i+1)
+ }
+ return buf.Bytes()
+}
+
+func TestScanInts(t *testing.T) {
+ testScanInts(t, scanInts)
+ testScanInts(t, func(r *RecursiveInt, b *bytes.Buffer) (err error) {
+ _, err = Fscan(b, r)
+ return
+ })
+}
+
+// 800 is small enough to not overflow the stack when using gccgo on a
+// platform that does not support split stack.
+const intCount = 800
+
+func testScanInts(t *testing.T, scan func(*RecursiveInt, *bytes.Buffer) error) {
+ r := new(RecursiveInt)
+ ints := makeInts(intCount)
+ buf := bytes.NewBuffer(ints)
+ err := scan(r, buf)
+ if err != nil {
+ t.Error("unexpected error", err)
+ }
+ i := 1
+ for ; r != nil; r = r.next {
+ if r.i != i {
+ t.Fatalf("bad scan: expected %d got %d", i, r.i)
+ }
+ i++
+ }
+ if i-1 != intCount {
+ t.Fatalf("bad scan count: expected %d got %d", intCount, i-1)
+ }
+}
+
+func BenchmarkScanInts(b *testing.B) {
+ b.StopTimer()
+ ints := makeInts(intCount)
+ var r RecursiveInt
+ for i := 0; i < b.N; i++ {
+ buf := bytes.NewBuffer(ints)
+ b.StartTimer()
+ scanInts(&r, buf)
+ b.StopTimer()
+ }
+}
+
+func BenchmarkScanRecursiveInt(b *testing.B) {
+ b.StopTimer()
+ ints := makeInts(intCount)
+ var r RecursiveInt
+ for i := 0; i < b.N; i++ {
+ buf := bytes.NewBuffer(ints)
+ b.StartTimer()
+ Fscan(buf, &r)
+ b.StopTimer()
+ }
+}
+
+func BenchmarkScanRecursiveIntReaderWrapper(b *testing.B) {
+ b.StopTimer()
+ ints := makeInts(intCount)
+ var r RecursiveInt
+ for i := 0; i < b.N; i++ {
+ buf := struct{ io.Reader }{strings.NewReader(string(ints))}
+ b.StartTimer()
+ Fscan(buf, &r)
+ b.StopTimer()
+ }
+}
+
+// Issue 9124.
+// %x on bytes couldn't handle non-space bytes terminating the scan.
+func TestHexBytes(t *testing.T) {
+ var a, b []byte
+ n, err := Sscanf("00010203", "%x", &a)
+ if n != 1 || err != nil {
+ t.Errorf("simple: got count, err = %d, %v; expected 1, nil", n, err)
+ }
+ check := func(msg string, x []byte) {
+ if len(x) != 4 {
+ t.Errorf("%s: bad length %d", msg, len(x))
+ }
+ for i, b := range x {
+ if int(b) != i {
+ t.Errorf("%s: bad x[%d] = %x", msg, i, x[i])
+ }
+ }
+ }
+ check("simple", a)
+ a = nil
+
+ n, err = Sscanf("00010203 00010203", "%x %x", &a, &b)
+ if n != 2 || err != nil {
+ t.Errorf("simple pair: got count, err = %d, %v; expected 2, nil", n, err)
+ }
+ check("simple pair a", a)
+ check("simple pair b", b)
+ a = nil
+ b = nil
+
+ n, err = Sscanf("00010203:", "%x", &a)
+ if n != 1 || err != nil {
+ t.Errorf("colon: got count, err = %d, %v; expected 1, nil", n, err)
+ }
+ check("colon", a)
+ a = nil
+
+ n, err = Sscanf("00010203:00010203", "%x:%x", &a, &b)
+ if n != 2 || err != nil {
+ t.Errorf("colon pair: got count, err = %d, %v; expected 2, nil", n, err)
+ }
+ check("colon pair a", a)
+ check("colon pair b", b)
+ a = nil
+ b = nil
+
+ // This one fails because there is a hex byte after the data,
+ // that is, an odd number of hex input bytes.
+ n, err = Sscanf("000102034:", "%x", &a)
+ if n != 0 || err == nil {
+ t.Errorf("odd count: got count, err = %d, %v; expected 0, error", n, err)
+ }
+}
+
+func TestScanNewlinesAreSpaces(t *testing.T) {
+ var a, b int
+ var tests = []struct {
+ name string
+ text string
+ count int
+ }{
+ {"newlines", "1\n2\n", 2},
+ {"no final newline", "1\n2", 2},
+ {"newlines with spaces ", "1 \n 2 \n", 2},
+ {"no final newline with spaces", "1 \n 2", 2},
+ }
+ for _, test := range tests {
+ n, err := Sscan(test.text, &a, &b)
+ if n != test.count {
+ t.Errorf("%s: expected to scan %d item(s), scanned %d", test.name, test.count, n)
+ }
+ if err != nil {
+ t.Errorf("%s: unexpected error: %s", test.name, err)
+ }
+ }
+}
+
+func TestScanlnNewlinesTerminate(t *testing.T) {
+ var a, b int
+ var tests = []struct {
+ name string
+ text string
+ count int
+ ok bool
+ }{
+ {"one line one item", "1\n", 1, false},
+ {"one line two items with spaces ", " 1 2 \n", 2, true},
+ {"one line two items no newline", " 1 2", 2, true},
+ {"two lines two items", "1\n2\n", 1, false},
+ }
+ for _, test := range tests {
+ n, err := Sscanln(test.text, &a, &b)
+ if n != test.count {
+ t.Errorf("%s: expected to scan %d item(s), scanned %d", test.name, test.count, n)
+ }
+ if test.ok && err != nil {
+ t.Errorf("%s: unexpected error: %s", test.name, err)
+ }
+ if !test.ok && err == nil {
+ t.Errorf("%s: expected error; got none", test.name)
+ }
+ }
+}
+
+func TestScanfNewlineMatchFormat(t *testing.T) {
+ var a, b int
+ var tests = []struct {
+ name string
+ text string
+ format string
+ count int
+ ok bool
+ }{
+ {"newline in both", "1\n2", "%d\n%d\n", 2, true},
+ {"newline in input", "1\n2", "%d %d", 1, false},
+ {"space-newline in input", "1 \n2", "%d %d", 1, false},
+ {"newline in format", "1 2", "%d\n%d", 1, false},
+ {"space-newline in format", "1 2", "%d \n%d", 1, false},
+ {"space-newline in both", "1 \n2", "%d \n%d", 2, true},
+ {"extra space in format", "1\n2", "%d\n %d", 2, true},
+ {"two extra spaces in format", "1\n2", "%d \n %d", 2, true},
+ {"space vs newline 0000", "1\n2", "%d\n%d", 2, true},
+ {"space vs newline 0001", "1\n2", "%d\n %d", 2, true},
+ {"space vs newline 0010", "1\n2", "%d \n%d", 2, true},
+ {"space vs newline 0011", "1\n2", "%d \n %d", 2, true},
+ {"space vs newline 0100", "1\n 2", "%d\n%d", 2, true},
+ {"space vs newline 0101", "1\n 2", "%d\n%d ", 2, true},
+ {"space vs newline 0110", "1\n 2", "%d \n%d", 2, true},
+ {"space vs newline 0111", "1\n 2", "%d \n %d", 2, true},
+ {"space vs newline 1000", "1 \n2", "%d\n%d", 2, true},
+ {"space vs newline 1001", "1 \n2", "%d\n %d", 2, true},
+ {"space vs newline 1010", "1 \n2", "%d \n%d", 2, true},
+ {"space vs newline 1011", "1 \n2", "%d \n %d", 2, true},
+ {"space vs newline 1100", "1 \n 2", "%d\n%d", 2, true},
+ {"space vs newline 1101", "1 \n 2", "%d\n %d", 2, true},
+ {"space vs newline 1110", "1 \n 2", "%d \n%d", 2, true},
+ {"space vs newline 1111", "1 \n 2", "%d \n %d", 2, true},
+ {"space vs newline no-percent 0000", "1\n2", "1\n2", 0, true},
+ {"space vs newline no-percent 0001", "1\n2", "1\n 2", 0, true},
+ {"space vs newline no-percent 0010", "1\n2", "1 \n2", 0, true},
+ {"space vs newline no-percent 0011", "1\n2", "1 \n 2", 0, true},
+ {"space vs newline no-percent 0100", "1\n 2", "1\n2", 0, false}, // fails: space after nl in input but not pattern
+ {"space vs newline no-percent 0101", "1\n 2", "1\n2 ", 0, false}, // fails: space after nl in input but not pattern
+ {"space vs newline no-percent 0110", "1\n 2", "1 \n2", 0, false}, // fails: space after nl in input but not pattern
+ {"space vs newline no-percent 0111", "1\n 2", "1 \n 2", 0, true},
+ {"space vs newline no-percent 1000", "1 \n2", "1\n2", 0, true},
+ {"space vs newline no-percent 1001", "1 \n2", "1\n 2", 0, true},
+ {"space vs newline no-percent 1010", "1 \n2", "1 \n2", 0, true},
+ {"space vs newline no-percent 1011", "1 \n2", "1 \n 2", 0, true},
+ {"space vs newline no-percent 1100", "1 \n 2", "1\n2", 0, false}, // fails: space after nl in input but not pattern
+ {"space vs newline no-percent 1101", "1 \n 2", "1\n 2", 0, true},
+ {"space vs newline no-percent 1110", "1 \n 2", "1 \n2", 0, false}, // fails: space after nl in input but not pattern
+ {"space vs newline no-percent 1111", "1 \n 2", "1 \n 2", 0, true},
+ }
+ for _, test := range tests {
+ var n int
+ var err error
+ if strings.Contains(test.format, "%") {
+ n, err = Sscanf(test.text, test.format, &a, &b)
+ } else {
+ n, err = Sscanf(test.text, test.format)
+ }
+ if n != test.count {
+ t.Errorf("%s: expected to scan %d item(s), scanned %d", test.name, test.count, n)
+ }
+ if test.ok && err != nil {
+ t.Errorf("%s: unexpected error: %s", test.name, err)
+ }
+ if !test.ok && err == nil {
+ t.Errorf("%s: expected error; got none", test.name)
+ }
+ }
+}
+
+// Test for issue 12090: Was unreading at EOF, double-scanning a byte.
+
+type hexBytes [2]byte
+
+func (h *hexBytes) Scan(ss ScanState, verb rune) error {
+ var b []byte
+ _, err := Fscanf(ss, "%4x", &b)
+ if err != nil {
+ panic(err) // Really shouldn't happen.
+ }
+ copy((*h)[:], b)
+ return err
+}
+
+func TestHexByte(t *testing.T) {
+ var h hexBytes
+ n, err := Sscanln("0123\n", &h)
+ if err != nil {
+ t.Fatal(err)
+ }
+ if n != 1 {
+ t.Fatalf("expected 1 item; scanned %d", n)
+ }
+ if h[0] != 0x01 || h[1] != 0x23 {
+ t.Fatalf("expected 0123 got %x", h)
+ }
+}
diff --git a/go/src/fmt/state_test.go b/go/src/fmt/state_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..fda660aa3241bbdec6bc81f39913fdd8e8d6b1b9
--- /dev/null
+++ b/go/src/fmt/state_test.go
@@ -0,0 +1,80 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package fmt_test
+
+import (
+ "fmt"
+ "testing"
+)
+
+type testState struct {
+ width int
+ widthOK bool
+ prec int
+ precOK bool
+ flag map[int]bool
+}
+
+var _ fmt.State = testState{}
+
+func (s testState) Write(b []byte) (n int, err error) {
+ panic("unimplemented")
+}
+
+func (s testState) Width() (wid int, ok bool) {
+ return s.width, s.widthOK
+}
+
+func (s testState) Precision() (prec int, ok bool) {
+ return s.prec, s.precOK
+}
+
+func (s testState) Flag(c int) bool {
+ return s.flag[c]
+}
+
+const NO = -1000
+
+func mkState(w, p int, flags string) testState {
+ s := testState{}
+ if w != NO {
+ s.width = w
+ s.widthOK = true
+ }
+ if p != NO {
+ s.prec = p
+ s.precOK = true
+ }
+ s.flag = make(map[int]bool)
+ for _, c := range flags {
+ s.flag[int(c)] = true
+ }
+ return s
+}
+
+func TestFormatString(t *testing.T) {
+ var tests = []struct {
+ width, prec int
+ flags string
+ result string
+ }{
+ {NO, NO, "", "%x"},
+ {NO, 3, "", "%.3x"},
+ {3, NO, "", "%3x"},
+ {7, 3, "", "%7.3x"},
+ {NO, NO, " +-#0", "% +-#0x"},
+ {7, 3, "+", "%+7.3x"},
+ {7, -3, "-", "%-7.-3x"},
+ {7, 3, " ", "% 7.3x"},
+ {7, 3, "#", "%#7.3x"},
+ {7, 3, "0", "%07.3x"},
+ }
+ for _, test := range tests {
+ got := fmt.FormatString(mkState(test.width, test.prec, test.flags), 'x')
+ if got != test.result {
+ t.Errorf("%v: got %s", test, got)
+ }
+ }
+}
diff --git a/go/src/fmt/stringer_example_test.go b/go/src/fmt/stringer_example_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..c77e78809cc56ccdfa0f13aaddeed1a7a58e3abc
--- /dev/null
+++ b/go/src/fmt/stringer_example_test.go
@@ -0,0 +1,29 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package fmt_test
+
+import (
+ "fmt"
+)
+
+// Animal has a Name and an Age to represent an animal.
+type Animal struct {
+ Name string
+ Age uint
+}
+
+// String makes Animal satisfy the Stringer interface.
+func (a Animal) String() string {
+ return fmt.Sprintf("%v (%d)", a.Name, a.Age)
+}
+
+func ExampleStringer() {
+ a := Animal{
+ Name: "Gopher",
+ Age: 2,
+ }
+ fmt.Println(a)
+ // Output: Gopher (2)
+}
diff --git a/go/src/fmt/stringer_test.go b/go/src/fmt/stringer_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..0ca3f522d622aa7d6b2af6a97f253fa3eca869b5
--- /dev/null
+++ b/go/src/fmt/stringer_test.go
@@ -0,0 +1,61 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package fmt_test
+
+import (
+ . "fmt"
+ "testing"
+)
+
+type TI int
+type TI8 int8
+type TI16 int16
+type TI32 int32
+type TI64 int64
+type TU uint
+type TU8 uint8
+type TU16 uint16
+type TU32 uint32
+type TU64 uint64
+type TUI uintptr
+type TF float64
+type TF32 float32
+type TF64 float64
+type TB bool
+type TS string
+
+func (v TI) String() string { return Sprintf("I: %d", int(v)) }
+func (v TI8) String() string { return Sprintf("I8: %d", int8(v)) }
+func (v TI16) String() string { return Sprintf("I16: %d", int16(v)) }
+func (v TI32) String() string { return Sprintf("I32: %d", int32(v)) }
+func (v TI64) String() string { return Sprintf("I64: %d", int64(v)) }
+func (v TU) String() string { return Sprintf("U: %d", uint(v)) }
+func (v TU8) String() string { return Sprintf("U8: %d", uint8(v)) }
+func (v TU16) String() string { return Sprintf("U16: %d", uint16(v)) }
+func (v TU32) String() string { return Sprintf("U32: %d", uint32(v)) }
+func (v TU64) String() string { return Sprintf("U64: %d", uint64(v)) }
+func (v TUI) String() string { return Sprintf("UI: %d", uintptr(v)) }
+func (v TF) String() string { return Sprintf("F: %f", float64(v)) }
+func (v TF32) String() string { return Sprintf("F32: %f", float32(v)) }
+func (v TF64) String() string { return Sprintf("F64: %f", float64(v)) }
+func (v TB) String() string { return Sprintf("B: %t", bool(v)) }
+func (v TS) String() string { return Sprintf("S: %q", string(v)) }
+
+func check(t *testing.T, got, want string) {
+ if got != want {
+ t.Error(got, "!=", want)
+ }
+}
+
+func TestStringer(t *testing.T) {
+ s := Sprintf("%v %v %v %v %v", TI(0), TI8(1), TI16(2), TI32(3), TI64(4))
+ check(t, s, "I: 0 I8: 1 I16: 2 I32: 3 I64: 4")
+ s = Sprintf("%v %v %v %v %v %v", TU(5), TU8(6), TU16(7), TU32(8), TU64(9), TUI(10))
+ check(t, s, "U: 5 U8: 6 U16: 7 U32: 8 U64: 9 UI: 10")
+ s = Sprintf("%v %v %v", TF(1.0), TF32(2.0), TF64(3.0))
+ check(t, s, "F: 1.000000 F32: 2.000000 F64: 3.000000")
+ s = Sprintf("%v %v", TB(true), TS("x"))
+ check(t, s, "B: true S: \"x\"")
+}
diff --git a/go/src/hash/example_test.go b/go/src/hash/example_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..f07b9aaa2c4898b5765ba66da0faf6cf48fa4e42
--- /dev/null
+++ b/go/src/hash/example_test.go
@@ -0,0 +1,51 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package hash_test
+
+import (
+ "bytes"
+ "crypto/sha256"
+ "encoding"
+ "fmt"
+ "log"
+)
+
+func Example_binaryMarshaler() {
+ const (
+ input1 = "The tunneling gopher digs downwards, "
+ input2 = "unaware of what he will find."
+ )
+
+ first := sha256.New()
+ first.Write([]byte(input1))
+
+ marshaler, ok := first.(encoding.BinaryMarshaler)
+ if !ok {
+ log.Fatal("first does not implement encoding.BinaryMarshaler")
+ }
+ state, err := marshaler.MarshalBinary()
+ if err != nil {
+ log.Fatal("unable to marshal hash:", err)
+ }
+
+ second := sha256.New()
+
+ unmarshaler, ok := second.(encoding.BinaryUnmarshaler)
+ if !ok {
+ log.Fatal("second does not implement encoding.BinaryUnmarshaler")
+ }
+ if err := unmarshaler.UnmarshalBinary(state); err != nil {
+ log.Fatal("unable to unmarshal hash:", err)
+ }
+
+ first.Write([]byte(input2))
+ second.Write([]byte(input2))
+
+ fmt.Printf("%x\n", first.Sum(nil))
+ fmt.Println(bytes.Equal(first.Sum(nil), second.Sum(nil)))
+ // Output:
+ // 57d51a066f3a39942649cd9a76c77e97ceab246756ff3888659e6aa5a07f4a52
+ // true
+}
diff --git a/go/src/hash/hash.go b/go/src/hash/hash.go
new file mode 100644
index 0000000000000000000000000000000000000000..24ee9929c9587d7873675febe6b4bb59e6f57a07
--- /dev/null
+++ b/go/src/hash/hash.go
@@ -0,0 +1,92 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package hash provides interfaces for hash functions.
+package hash
+
+import "io"
+
+// Hash is the common interface implemented by all hash functions.
+//
+// Hash implementations in the standard library (e.g. [hash/crc32] and
+// [crypto/sha256]) implement the [encoding.BinaryMarshaler], [encoding.BinaryAppender],
+// [encoding.BinaryUnmarshaler] and [Cloner] interfaces. Marshaling a hash implementation
+// allows its internal state to be saved and used for additional processing
+// later, without having to re-write the data previously written to the hash.
+// The hash state may contain portions of the input in its original form,
+// which users are expected to handle for any possible security implications.
+//
+// Compatibility: Any future changes to hash or crypto packages will endeavor
+// to maintain compatibility with state encoded using previous versions.
+// That is, any released versions of the packages should be able to
+// decode data written with any previously released version,
+// subject to issues such as security fixes.
+// See the Go compatibility document for background: https://golang.org/doc/go1compat
+type Hash interface {
+ // Write (via the embedded io.Writer interface) adds more data to the running hash.
+ // It never returns an error.
+ io.Writer
+
+ // Sum appends the current hash to b and returns the resulting slice.
+ // It does not change the underlying hash state.
+ Sum(b []byte) []byte
+
+ // Reset resets the Hash to its initial state.
+ Reset()
+
+ // Size returns the number of bytes Sum will return.
+ Size() int
+
+ // BlockSize returns the hash's underlying block size.
+ // The Write method must be able to accept any amount
+ // of data, but it may operate more efficiently if all writes
+ // are a multiple of the block size.
+ BlockSize() int
+}
+
+// Hash32 is the common interface implemented by all 32-bit hash functions.
+type Hash32 interface {
+ Hash
+ Sum32() uint32
+}
+
+// Hash64 is the common interface implemented by all 64-bit hash functions.
+type Hash64 interface {
+ Hash
+ Sum64() uint64
+}
+
+// A Cloner is a hash function whose state can be cloned, returning a value with
+// equivalent and independent state.
+//
+// All [Hash] implementations in the standard library implement this interface,
+// unless GOFIPS140=v1.0.0 is set.
+//
+// If a hash can only determine at runtime if it can be cloned (e.g. if it wraps
+// another hash), Clone may return an error wrapping [errors.ErrUnsupported].
+// Otherwise, Clone must always return a nil error.
+type Cloner interface {
+ Hash
+ Clone() (Cloner, error)
+}
+
+// XOF (extendable output function) is a hash function with arbitrary or unlimited output length.
+type XOF interface {
+ // Write absorbs more data into the XOF's state. It panics if called
+ // after Read.
+ io.Writer
+
+ // Read reads more output from the XOF. It may return io.EOF if there
+ // is a limit to the XOF output length.
+ io.Reader
+
+ // Reset resets the XOF to its initial state.
+ Reset()
+
+ // BlockSize returns the XOF's underlying block size.
+ // The Write method must be able to accept any amount
+ // of data, but it may operate more efficiently if all writes
+ // are a multiple of the block size.
+ BlockSize() int
+}
diff --git a/go/src/hash/marshal_test.go b/go/src/hash/marshal_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..3091f7a67acedeaf72fd3851cf295c1e7bd88e8f
--- /dev/null
+++ b/go/src/hash/marshal_test.go
@@ -0,0 +1,107 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test that the hashes in the standard library implement
+// BinaryMarshaler, BinaryUnmarshaler,
+// and lock in the current representations.
+
+package hash_test
+
+import (
+ "bytes"
+ "crypto/md5"
+ "crypto/sha1"
+ "crypto/sha256"
+ "crypto/sha512"
+ "encoding"
+ "encoding/hex"
+ "hash"
+ "hash/adler32"
+ "hash/crc32"
+ "hash/crc64"
+ "hash/fnv"
+ "testing"
+)
+
+func fromHex(s string) []byte {
+ b, err := hex.DecodeString(s)
+ if err != nil {
+ panic(err)
+ }
+ return b
+}
+
+var marshalTests = []struct {
+ name string
+ new func() hash.Hash
+ golden []byte
+}{
+ {"adler32", func() hash.Hash { return adler32.New() }, fromHex("61646c01460a789d")},
+ {"crc32", func() hash.Hash { return crc32.NewIEEE() }, fromHex("63726301ca87914dc956d3e8")},
+ {"crc64", func() hash.Hash { return crc64.New(crc64.MakeTable(crc64.ISO)) }, fromHex("6372630273ba8484bbcd5def5d51c83c581695be")},
+ {"fnv32", func() hash.Hash { return fnv.New32() }, fromHex("666e760171ba3d77")},
+ {"fnv32a", func() hash.Hash { return fnv.New32a() }, fromHex("666e76027439f86f")},
+ {"fnv64", func() hash.Hash { return fnv.New64() }, fromHex("666e7603cc64e0e97692c637")},
+ {"fnv64a", func() hash.Hash { return fnv.New64a() }, fromHex("666e7604c522af9b0dede66f")},
+ {"fnv128", func() hash.Hash { return fnv.New128() }, fromHex("666e760561587a70a0f66d7981dc980e2cabbaf7")},
+ {"fnv128a", func() hash.Hash { return fnv.New128a() }, fromHex("666e7606a955802b0136cb67622b461d9f91e6ff")},
+ {"md5", md5.New, fromHex("6d643501a91b0023007aa14740a3979210b5f024c0c1c2c3c4c5c6c7c8c9cacbcccdcecfd0d1d2d3d4d5d6d7d8d9dadbdcdddedfe0e1e2e3e4e5e6e7e8e9eaebecedeeeff0f1f2f3f4f5f6f7f80000000000000000000000000000f9")},
+ {"sha1", sha1.New, fromHex("736861016dad5acb4dc003952f7a0b352ee5537ec381a228c0c1c2c3c4c5c6c7c8c9cacbcccdcecfd0d1d2d3d4d5d6d7d8d9dadbdcdddedfe0e1e2e3e4e5e6e7e8e9eaebecedeeeff0f1f2f3f4f5f6f7f80000000000000000000000000000f9")},
+ {"sha224", sha256.New224, fromHex("73686102f8b92fc047c9b4d82f01a6370841277b7a0d92108440178c83db855a8e66c2d9c0c1c2c3c4c5c6c7c8c9cacbcccdcecfd0d1d2d3d4d5d6d7d8d9dadbdcdddedfe0e1e2e3e4e5e6e7e8e9eaebecedeeeff0f1f2f3f4f5f6f7f80000000000000000000000000000f9")},
+ {"sha256", sha256.New, fromHex("736861032bed68b99987cae48183b2b049d393d0050868e4e8ba3730e9112b08765929b7c0c1c2c3c4c5c6c7c8c9cacbcccdcecfd0d1d2d3d4d5d6d7d8d9dadbdcdddedfe0e1e2e3e4e5e6e7e8e9eaebecedeeeff0f1f2f3f4f5f6f7f80000000000000000000000000000f9")},
+ {"sha384", sha512.New384, fromHex("736861046f1664d213dd802f7c47bc50637cf93592570a2b8695839148bf38341c6eacd05326452ef1cbe64d90f1ef73bb5ac7d2803565467d0ddb10c5ee3fc050f9f0c1808182838485868788898a8b8c8d8e8f909192939495969798999a9b9c9d9e9fa0a1a2a3a4a5a6a7a8a9aaabacadaeafb0b1b2b3b4b5b6b7b8b9babbbcbdbebfc0c1c2c3c4c5c6c7c8c9cacbcccdcecfd0d1d2d3d4d5d6d7d8d9dadbdcdddedfe0e1e2e3e4e5e6e7e8e9eaebecedeeeff0f1f2f3f4f5f6f7f80000000000000000000000000000f9")},
+ {"sha512_224", sha512.New512_224, fromHex("736861056f1a450ec15af20572d0d1ee6518104d7cbbbe79a038557af5450ed7dbd420b53b7335209e951b4d9aff401f90549b9604fa3d823fbb8581c73582a88aa84022808182838485868788898a8b8c8d8e8f909192939495969798999a9b9c9d9e9fa0a1a2a3a4a5a6a7a8a9aaabacadaeafb0b1b2b3b4b5b6b7b8b9babbbcbdbebfc0c1c2c3c4c5c6c7c8c9cacbcccdcecfd0d1d2d3d4d5d6d7d8d9dadbdcdddedfe0e1e2e3e4e5e6e7e8e9eaebecedeeeff0f1f2f3f4f5f6f7f80000000000000000000000000000f9")},
+ {"sha512_256", sha512.New512_256, fromHex("736861067c541f1d1a72536b1f5dad64026bcc7c508f8a2126b51f46f8b9bff63a26fee70980718031e96832e95547f4fe76160ff84076db53b4549b86354af8e17b5116808182838485868788898a8b8c8d8e8f909192939495969798999a9b9c9d9e9fa0a1a2a3a4a5a6a7a8a9aaabacadaeafb0b1b2b3b4b5b6b7b8b9babbbcbdbebfc0c1c2c3c4c5c6c7c8c9cacbcccdcecfd0d1d2d3d4d5d6d7d8d9dadbdcdddedfe0e1e2e3e4e5e6e7e8e9eaebecedeeeff0f1f2f3f4f5f6f7f80000000000000000000000000000f9")},
+ {"sha512", sha512.New, fromHex("736861078e03953cd57cd6879321270afa70c5827bb5b69be59a8f0130147e94f2aedf7bdc01c56c92343ca8bd837bb7f0208f5a23e155694516b6f147099d491a30b151808182838485868788898a8b8c8d8e8f909192939495969798999a9b9c9d9e9fa0a1a2a3a4a5a6a7a8a9aaabacadaeafb0b1b2b3b4b5b6b7b8b9babbbcbdbebfc0c1c2c3c4c5c6c7c8c9cacbcccdcecfd0d1d2d3d4d5d6d7d8d9dadbdcdddedfe0e1e2e3e4e5e6e7e8e9eaebecedeeeff0f1f2f3f4f5f6f7f80000000000000000000000000000f9")},
+}
+
+func TestMarshalHash(t *testing.T) {
+ for _, tt := range marshalTests {
+ t.Run(tt.name, func(t *testing.T) {
+ buf := make([]byte, 256)
+ for i := range buf {
+ buf[i] = byte(i)
+ }
+
+ h := tt.new()
+ h.Write(buf[:256])
+ sum := h.Sum(nil)
+
+ h2 := tt.new()
+ h3 := tt.new()
+ const split = 249
+ for i := 0; i < split; i++ {
+ h2.Write(buf[i : i+1])
+ }
+ h2m, ok := h2.(encoding.BinaryMarshaler)
+ if !ok {
+ t.Fatalf("Hash does not implement MarshalBinary")
+ }
+ enc, err := h2m.MarshalBinary()
+ if err != nil {
+ t.Fatalf("MarshalBinary: %v", err)
+ }
+ if !bytes.Equal(enc, tt.golden) {
+ t.Errorf("MarshalBinary = %x, want %x", enc, tt.golden)
+ }
+ h3u, ok := h3.(encoding.BinaryUnmarshaler)
+ if !ok {
+ t.Fatalf("Hash does not implement UnmarshalBinary")
+ }
+ if err := h3u.UnmarshalBinary(enc); err != nil {
+ t.Fatalf("UnmarshalBinary: %v", err)
+ }
+ h2.Write(buf[split:])
+ h3.Write(buf[split:])
+ sum2 := h2.Sum(nil)
+ sum3 := h3.Sum(nil)
+ if !bytes.Equal(sum2, sum) {
+ t.Fatalf("Sum after MarshalBinary = %x, want %x", sum2, sum)
+ }
+ if !bytes.Equal(sum3, sum) {
+ t.Fatalf("Sum after UnmarshalBinary = %x, want %x", sum3, sum)
+ }
+ })
+ }
+}
diff --git a/go/src/hash/test_cases.txt b/go/src/hash/test_cases.txt
new file mode 100644
index 0000000000000000000000000000000000000000..26d3ccc052495c1517ce4e5a30af947c3fb176c0
--- /dev/null
+++ b/go/src/hash/test_cases.txt
@@ -0,0 +1,31 @@
+
+a
+ab
+abc
+abcd
+abcde
+abcdef
+abcdefg
+abcdefgh
+abcdefghi
+abcdefghij
+Discard medicine more than two years old.
+He who has a shady past knows that nice guys finish last.
+I wouldn't marry him with a ten foot pole.
+Free! Free!/A trip/to Mars/for 900/empty jars/Burma Shave
+The days of the digital watch are numbered. -Tom Stoppard
+Nepal premier won't resign.
+For every action there is an equal and opposite government program.
+His money is twice tainted: 'taint yours and 'taint mine.
+There is no reason for any individual to have a computer in their home. -Ken Olsen, 1977
+It's a tiny change to the code and not completely disgusting. - Bob Manchek
+size: a.out: bad magic
+The major problem is with sendmail. -Mark Horton
+Give me a rock, paper and scissors and I will move the world. CCFestoon
+If the enemy is within range, then so are you.
+It's well we cannot hear the screams/That we create in others' dreams.
+You remind me of a TV show, but that's all right: I watch it anyway.
+C is as portable as Stonehedge!!
+Even if I could be Shakespeare, I think I should still choose to be Faraday. - A. Huxley
+The fugacity of a constituent in a mixture of gases at a given temperature is proportional to its mole fraction. Lewis-Randall Rule
+How can you write a big system without C++? -Paul Glick
diff --git a/go/src/hash/test_gen.awk b/go/src/hash/test_gen.awk
new file mode 100644
index 0000000000000000000000000000000000000000..804f786795fa84cae233259bde18c1d7997ffa74
--- /dev/null
+++ b/go/src/hash/test_gen.awk
@@ -0,0 +1,14 @@
+# Copyright 2009 The Go Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+
+# awk -f test_gen.awk test_cases.txt
+# generates test case table.
+# edit next line to set particular reference implementation and name.
+BEGIN { cmd = "echo -n `9 sha1sum`"; name = "Sha1Test" }
+{
+ printf("\t%s{ \"", name);
+ printf("%s", $0) |cmd;
+ close(cmd);
+ printf("\", \"%s\" },\n", $0);
+}
diff --git a/go/src/html/entity.go b/go/src/html/entity.go
new file mode 100644
index 0000000000000000000000000000000000000000..421a54ab572eb27cfa15b2f415007ae751bb4a64
--- /dev/null
+++ b/go/src/html/entity.go
@@ -0,0 +1,2261 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package html
+
+import "sync"
+
+// All entities that do not end with ';' are 6 or fewer bytes long.
+const longestEntityWithoutSemicolon = 6
+
+// entityMaps returns entity and entity2.
+//
+// entity is a map from HTML entity names to their values. The semicolon matters:
+// https://html.spec.whatwg.org/multipage/named-characters.html
+// lists both "amp" and "amp;" as two separate entries.
+// Note that the HTML5 list is larger than the HTML4 list at
+// http://www.w3.org/TR/html4/sgml/entities.html
+//
+// entity2 is a map of HTML entities to two unicode codepoints.
+var entityMaps = sync.OnceValues(func() (entity map[string]rune, entity2 map[string][2]rune) {
+ entity = map[string]rune{
+ "AElig;": '\U000000C6',
+ "AMP;": '\U00000026',
+ "Aacute;": '\U000000C1',
+ "Abreve;": '\U00000102',
+ "Acirc;": '\U000000C2',
+ "Acy;": '\U00000410',
+ "Afr;": '\U0001D504',
+ "Agrave;": '\U000000C0',
+ "Alpha;": '\U00000391',
+ "Amacr;": '\U00000100',
+ "And;": '\U00002A53',
+ "Aogon;": '\U00000104',
+ "Aopf;": '\U0001D538',
+ "ApplyFunction;": '\U00002061',
+ "Aring;": '\U000000C5',
+ "Ascr;": '\U0001D49C',
+ "Assign;": '\U00002254',
+ "Atilde;": '\U000000C3',
+ "Auml;": '\U000000C4',
+ "Backslash;": '\U00002216',
+ "Barv;": '\U00002AE7',
+ "Barwed;": '\U00002306',
+ "Bcy;": '\U00000411',
+ "Because;": '\U00002235',
+ "Bernoullis;": '\U0000212C',
+ "Beta;": '\U00000392',
+ "Bfr;": '\U0001D505',
+ "Bopf;": '\U0001D539',
+ "Breve;": '\U000002D8',
+ "Bscr;": '\U0000212C',
+ "Bumpeq;": '\U0000224E',
+ "CHcy;": '\U00000427',
+ "COPY;": '\U000000A9',
+ "Cacute;": '\U00000106',
+ "Cap;": '\U000022D2',
+ "CapitalDifferentialD;": '\U00002145',
+ "Cayleys;": '\U0000212D',
+ "Ccaron;": '\U0000010C',
+ "Ccedil;": '\U000000C7',
+ "Ccirc;": '\U00000108',
+ "Cconint;": '\U00002230',
+ "Cdot;": '\U0000010A',
+ "Cedilla;": '\U000000B8',
+ "CenterDot;": '\U000000B7',
+ "Cfr;": '\U0000212D',
+ "Chi;": '\U000003A7',
+ "CircleDot;": '\U00002299',
+ "CircleMinus;": '\U00002296',
+ "CirclePlus;": '\U00002295',
+ "CircleTimes;": '\U00002297',
+ "ClockwiseContourIntegral;": '\U00002232',
+ "CloseCurlyDoubleQuote;": '\U0000201D',
+ "CloseCurlyQuote;": '\U00002019',
+ "Colon;": '\U00002237',
+ "Colone;": '\U00002A74',
+ "Congruent;": '\U00002261',
+ "Conint;": '\U0000222F',
+ "ContourIntegral;": '\U0000222E',
+ "Copf;": '\U00002102',
+ "Coproduct;": '\U00002210',
+ "CounterClockwiseContourIntegral;": '\U00002233',
+ "Cross;": '\U00002A2F',
+ "Cscr;": '\U0001D49E',
+ "Cup;": '\U000022D3',
+ "CupCap;": '\U0000224D',
+ "DD;": '\U00002145',
+ "DDotrahd;": '\U00002911',
+ "DJcy;": '\U00000402',
+ "DScy;": '\U00000405',
+ "DZcy;": '\U0000040F',
+ "Dagger;": '\U00002021',
+ "Darr;": '\U000021A1',
+ "Dashv;": '\U00002AE4',
+ "Dcaron;": '\U0000010E',
+ "Dcy;": '\U00000414',
+ "Del;": '\U00002207',
+ "Delta;": '\U00000394',
+ "Dfr;": '\U0001D507',
+ "DiacriticalAcute;": '\U000000B4',
+ "DiacriticalDot;": '\U000002D9',
+ "DiacriticalDoubleAcute;": '\U000002DD',
+ "DiacriticalGrave;": '\U00000060',
+ "DiacriticalTilde;": '\U000002DC',
+ "Diamond;": '\U000022C4',
+ "DifferentialD;": '\U00002146',
+ "Dopf;": '\U0001D53B',
+ "Dot;": '\U000000A8',
+ "DotDot;": '\U000020DC',
+ "DotEqual;": '\U00002250',
+ "DoubleContourIntegral;": '\U0000222F',
+ "DoubleDot;": '\U000000A8',
+ "DoubleDownArrow;": '\U000021D3',
+ "DoubleLeftArrow;": '\U000021D0',
+ "DoubleLeftRightArrow;": '\U000021D4',
+ "DoubleLeftTee;": '\U00002AE4',
+ "DoubleLongLeftArrow;": '\U000027F8',
+ "DoubleLongLeftRightArrow;": '\U000027FA',
+ "DoubleLongRightArrow;": '\U000027F9',
+ "DoubleRightArrow;": '\U000021D2',
+ "DoubleRightTee;": '\U000022A8',
+ "DoubleUpArrow;": '\U000021D1',
+ "DoubleUpDownArrow;": '\U000021D5',
+ "DoubleVerticalBar;": '\U00002225',
+ "DownArrow;": '\U00002193',
+ "DownArrowBar;": '\U00002913',
+ "DownArrowUpArrow;": '\U000021F5',
+ "DownBreve;": '\U00000311',
+ "DownLeftRightVector;": '\U00002950',
+ "DownLeftTeeVector;": '\U0000295E',
+ "DownLeftVector;": '\U000021BD',
+ "DownLeftVectorBar;": '\U00002956',
+ "DownRightTeeVector;": '\U0000295F',
+ "DownRightVector;": '\U000021C1',
+ "DownRightVectorBar;": '\U00002957',
+ "DownTee;": '\U000022A4',
+ "DownTeeArrow;": '\U000021A7',
+ "Downarrow;": '\U000021D3',
+ "Dscr;": '\U0001D49F',
+ "Dstrok;": '\U00000110',
+ "ENG;": '\U0000014A',
+ "ETH;": '\U000000D0',
+ "Eacute;": '\U000000C9',
+ "Ecaron;": '\U0000011A',
+ "Ecirc;": '\U000000CA',
+ "Ecy;": '\U0000042D',
+ "Edot;": '\U00000116',
+ "Efr;": '\U0001D508',
+ "Egrave;": '\U000000C8',
+ "Element;": '\U00002208',
+ "Emacr;": '\U00000112',
+ "EmptySmallSquare;": '\U000025FB',
+ "EmptyVerySmallSquare;": '\U000025AB',
+ "Eogon;": '\U00000118',
+ "Eopf;": '\U0001D53C',
+ "Epsilon;": '\U00000395',
+ "Equal;": '\U00002A75',
+ "EqualTilde;": '\U00002242',
+ "Equilibrium;": '\U000021CC',
+ "Escr;": '\U00002130',
+ "Esim;": '\U00002A73',
+ "Eta;": '\U00000397',
+ "Euml;": '\U000000CB',
+ "Exists;": '\U00002203',
+ "ExponentialE;": '\U00002147',
+ "Fcy;": '\U00000424',
+ "Ffr;": '\U0001D509',
+ "FilledSmallSquare;": '\U000025FC',
+ "FilledVerySmallSquare;": '\U000025AA',
+ "Fopf;": '\U0001D53D',
+ "ForAll;": '\U00002200',
+ "Fouriertrf;": '\U00002131',
+ "Fscr;": '\U00002131',
+ "GJcy;": '\U00000403',
+ "GT;": '\U0000003E',
+ "Gamma;": '\U00000393',
+ "Gammad;": '\U000003DC',
+ "Gbreve;": '\U0000011E',
+ "Gcedil;": '\U00000122',
+ "Gcirc;": '\U0000011C',
+ "Gcy;": '\U00000413',
+ "Gdot;": '\U00000120',
+ "Gfr;": '\U0001D50A',
+ "Gg;": '\U000022D9',
+ "Gopf;": '\U0001D53E',
+ "GreaterEqual;": '\U00002265',
+ "GreaterEqualLess;": '\U000022DB',
+ "GreaterFullEqual;": '\U00002267',
+ "GreaterGreater;": '\U00002AA2',
+ "GreaterLess;": '\U00002277',
+ "GreaterSlantEqual;": '\U00002A7E',
+ "GreaterTilde;": '\U00002273',
+ "Gscr;": '\U0001D4A2',
+ "Gt;": '\U0000226B',
+ "HARDcy;": '\U0000042A',
+ "Hacek;": '\U000002C7',
+ "Hat;": '\U0000005E',
+ "Hcirc;": '\U00000124',
+ "Hfr;": '\U0000210C',
+ "HilbertSpace;": '\U0000210B',
+ "Hopf;": '\U0000210D',
+ "HorizontalLine;": '\U00002500',
+ "Hscr;": '\U0000210B',
+ "Hstrok;": '\U00000126',
+ "HumpDownHump;": '\U0000224E',
+ "HumpEqual;": '\U0000224F',
+ "IEcy;": '\U00000415',
+ "IJlig;": '\U00000132',
+ "IOcy;": '\U00000401',
+ "Iacute;": '\U000000CD',
+ "Icirc;": '\U000000CE',
+ "Icy;": '\U00000418',
+ "Idot;": '\U00000130',
+ "Ifr;": '\U00002111',
+ "Igrave;": '\U000000CC',
+ "Im;": '\U00002111',
+ "Imacr;": '\U0000012A',
+ "ImaginaryI;": '\U00002148',
+ "Implies;": '\U000021D2',
+ "Int;": '\U0000222C',
+ "Integral;": '\U0000222B',
+ "Intersection;": '\U000022C2',
+ "InvisibleComma;": '\U00002063',
+ "InvisibleTimes;": '\U00002062',
+ "Iogon;": '\U0000012E',
+ "Iopf;": '\U0001D540',
+ "Iota;": '\U00000399',
+ "Iscr;": '\U00002110',
+ "Itilde;": '\U00000128',
+ "Iukcy;": '\U00000406',
+ "Iuml;": '\U000000CF',
+ "Jcirc;": '\U00000134',
+ "Jcy;": '\U00000419',
+ "Jfr;": '\U0001D50D',
+ "Jopf;": '\U0001D541',
+ "Jscr;": '\U0001D4A5',
+ "Jsercy;": '\U00000408',
+ "Jukcy;": '\U00000404',
+ "KHcy;": '\U00000425',
+ "KJcy;": '\U0000040C',
+ "Kappa;": '\U0000039A',
+ "Kcedil;": '\U00000136',
+ "Kcy;": '\U0000041A',
+ "Kfr;": '\U0001D50E',
+ "Kopf;": '\U0001D542',
+ "Kscr;": '\U0001D4A6',
+ "LJcy;": '\U00000409',
+ "LT;": '\U0000003C',
+ "Lacute;": '\U00000139',
+ "Lambda;": '\U0000039B',
+ "Lang;": '\U000027EA',
+ "Laplacetrf;": '\U00002112',
+ "Larr;": '\U0000219E',
+ "Lcaron;": '\U0000013D',
+ "Lcedil;": '\U0000013B',
+ "Lcy;": '\U0000041B',
+ "LeftAngleBracket;": '\U000027E8',
+ "LeftArrow;": '\U00002190',
+ "LeftArrowBar;": '\U000021E4',
+ "LeftArrowRightArrow;": '\U000021C6',
+ "LeftCeiling;": '\U00002308',
+ "LeftDoubleBracket;": '\U000027E6',
+ "LeftDownTeeVector;": '\U00002961',
+ "LeftDownVector;": '\U000021C3',
+ "LeftDownVectorBar;": '\U00002959',
+ "LeftFloor;": '\U0000230A',
+ "LeftRightArrow;": '\U00002194',
+ "LeftRightVector;": '\U0000294E',
+ "LeftTee;": '\U000022A3',
+ "LeftTeeArrow;": '\U000021A4',
+ "LeftTeeVector;": '\U0000295A',
+ "LeftTriangle;": '\U000022B2',
+ "LeftTriangleBar;": '\U000029CF',
+ "LeftTriangleEqual;": '\U000022B4',
+ "LeftUpDownVector;": '\U00002951',
+ "LeftUpTeeVector;": '\U00002960',
+ "LeftUpVector;": '\U000021BF',
+ "LeftUpVectorBar;": '\U00002958',
+ "LeftVector;": '\U000021BC',
+ "LeftVectorBar;": '\U00002952',
+ "Leftarrow;": '\U000021D0',
+ "Leftrightarrow;": '\U000021D4',
+ "LessEqualGreater;": '\U000022DA',
+ "LessFullEqual;": '\U00002266',
+ "LessGreater;": '\U00002276',
+ "LessLess;": '\U00002AA1',
+ "LessSlantEqual;": '\U00002A7D',
+ "LessTilde;": '\U00002272',
+ "Lfr;": '\U0001D50F',
+ "Ll;": '\U000022D8',
+ "Lleftarrow;": '\U000021DA',
+ "Lmidot;": '\U0000013F',
+ "LongLeftArrow;": '\U000027F5',
+ "LongLeftRightArrow;": '\U000027F7',
+ "LongRightArrow;": '\U000027F6',
+ "Longleftarrow;": '\U000027F8',
+ "Longleftrightarrow;": '\U000027FA',
+ "Longrightarrow;": '\U000027F9',
+ "Lopf;": '\U0001D543',
+ "LowerLeftArrow;": '\U00002199',
+ "LowerRightArrow;": '\U00002198',
+ "Lscr;": '\U00002112',
+ "Lsh;": '\U000021B0',
+ "Lstrok;": '\U00000141',
+ "Lt;": '\U0000226A',
+ "Map;": '\U00002905',
+ "Mcy;": '\U0000041C',
+ "MediumSpace;": '\U0000205F',
+ "Mellintrf;": '\U00002133',
+ "Mfr;": '\U0001D510',
+ "MinusPlus;": '\U00002213',
+ "Mopf;": '\U0001D544',
+ "Mscr;": '\U00002133',
+ "Mu;": '\U0000039C',
+ "NJcy;": '\U0000040A',
+ "Nacute;": '\U00000143',
+ "Ncaron;": '\U00000147',
+ "Ncedil;": '\U00000145',
+ "Ncy;": '\U0000041D',
+ "NegativeMediumSpace;": '\U0000200B',
+ "NegativeThickSpace;": '\U0000200B',
+ "NegativeThinSpace;": '\U0000200B',
+ "NegativeVeryThinSpace;": '\U0000200B',
+ "NestedGreaterGreater;": '\U0000226B',
+ "NestedLessLess;": '\U0000226A',
+ "NewLine;": '\U0000000A',
+ "Nfr;": '\U0001D511',
+ "NoBreak;": '\U00002060',
+ "NonBreakingSpace;": '\U000000A0',
+ "Nopf;": '\U00002115',
+ "Not;": '\U00002AEC',
+ "NotCongruent;": '\U00002262',
+ "NotCupCap;": '\U0000226D',
+ "NotDoubleVerticalBar;": '\U00002226',
+ "NotElement;": '\U00002209',
+ "NotEqual;": '\U00002260',
+ "NotExists;": '\U00002204',
+ "NotGreater;": '\U0000226F',
+ "NotGreaterEqual;": '\U00002271',
+ "NotGreaterLess;": '\U00002279',
+ "NotGreaterTilde;": '\U00002275',
+ "NotLeftTriangle;": '\U000022EA',
+ "NotLeftTriangleEqual;": '\U000022EC',
+ "NotLess;": '\U0000226E',
+ "NotLessEqual;": '\U00002270',
+ "NotLessGreater;": '\U00002278',
+ "NotLessTilde;": '\U00002274',
+ "NotPrecedes;": '\U00002280',
+ "NotPrecedesSlantEqual;": '\U000022E0',
+ "NotReverseElement;": '\U0000220C',
+ "NotRightTriangle;": '\U000022EB',
+ "NotRightTriangleEqual;": '\U000022ED',
+ "NotSquareSubsetEqual;": '\U000022E2',
+ "NotSquareSupersetEqual;": '\U000022E3',
+ "NotSubsetEqual;": '\U00002288',
+ "NotSucceeds;": '\U00002281',
+ "NotSucceedsSlantEqual;": '\U000022E1',
+ "NotSupersetEqual;": '\U00002289',
+ "NotTilde;": '\U00002241',
+ "NotTildeEqual;": '\U00002244',
+ "NotTildeFullEqual;": '\U00002247',
+ "NotTildeTilde;": '\U00002249',
+ "NotVerticalBar;": '\U00002224',
+ "Nscr;": '\U0001D4A9',
+ "Ntilde;": '\U000000D1',
+ "Nu;": '\U0000039D',
+ "OElig;": '\U00000152',
+ "Oacute;": '\U000000D3',
+ "Ocirc;": '\U000000D4',
+ "Ocy;": '\U0000041E',
+ "Odblac;": '\U00000150',
+ "Ofr;": '\U0001D512',
+ "Ograve;": '\U000000D2',
+ "Omacr;": '\U0000014C',
+ "Omega;": '\U000003A9',
+ "Omicron;": '\U0000039F',
+ "Oopf;": '\U0001D546',
+ "OpenCurlyDoubleQuote;": '\U0000201C',
+ "OpenCurlyQuote;": '\U00002018',
+ "Or;": '\U00002A54',
+ "Oscr;": '\U0001D4AA',
+ "Oslash;": '\U000000D8',
+ "Otilde;": '\U000000D5',
+ "Otimes;": '\U00002A37',
+ "Ouml;": '\U000000D6',
+ "OverBar;": '\U0000203E',
+ "OverBrace;": '\U000023DE',
+ "OverBracket;": '\U000023B4',
+ "OverParenthesis;": '\U000023DC',
+ "PartialD;": '\U00002202',
+ "Pcy;": '\U0000041F',
+ "Pfr;": '\U0001D513',
+ "Phi;": '\U000003A6',
+ "Pi;": '\U000003A0',
+ "PlusMinus;": '\U000000B1',
+ "Poincareplane;": '\U0000210C',
+ "Popf;": '\U00002119',
+ "Pr;": '\U00002ABB',
+ "Precedes;": '\U0000227A',
+ "PrecedesEqual;": '\U00002AAF',
+ "PrecedesSlantEqual;": '\U0000227C',
+ "PrecedesTilde;": '\U0000227E',
+ "Prime;": '\U00002033',
+ "Product;": '\U0000220F',
+ "Proportion;": '\U00002237',
+ "Proportional;": '\U0000221D',
+ "Pscr;": '\U0001D4AB',
+ "Psi;": '\U000003A8',
+ "QUOT;": '\U00000022',
+ "Qfr;": '\U0001D514',
+ "Qopf;": '\U0000211A',
+ "Qscr;": '\U0001D4AC',
+ "RBarr;": '\U00002910',
+ "REG;": '\U000000AE',
+ "Racute;": '\U00000154',
+ "Rang;": '\U000027EB',
+ "Rarr;": '\U000021A0',
+ "Rarrtl;": '\U00002916',
+ "Rcaron;": '\U00000158',
+ "Rcedil;": '\U00000156',
+ "Rcy;": '\U00000420',
+ "Re;": '\U0000211C',
+ "ReverseElement;": '\U0000220B',
+ "ReverseEquilibrium;": '\U000021CB',
+ "ReverseUpEquilibrium;": '\U0000296F',
+ "Rfr;": '\U0000211C',
+ "Rho;": '\U000003A1',
+ "RightAngleBracket;": '\U000027E9',
+ "RightArrow;": '\U00002192',
+ "RightArrowBar;": '\U000021E5',
+ "RightArrowLeftArrow;": '\U000021C4',
+ "RightCeiling;": '\U00002309',
+ "RightDoubleBracket;": '\U000027E7',
+ "RightDownTeeVector;": '\U0000295D',
+ "RightDownVector;": '\U000021C2',
+ "RightDownVectorBar;": '\U00002955',
+ "RightFloor;": '\U0000230B',
+ "RightTee;": '\U000022A2',
+ "RightTeeArrow;": '\U000021A6',
+ "RightTeeVector;": '\U0000295B',
+ "RightTriangle;": '\U000022B3',
+ "RightTriangleBar;": '\U000029D0',
+ "RightTriangleEqual;": '\U000022B5',
+ "RightUpDownVector;": '\U0000294F',
+ "RightUpTeeVector;": '\U0000295C',
+ "RightUpVector;": '\U000021BE',
+ "RightUpVectorBar;": '\U00002954',
+ "RightVector;": '\U000021C0',
+ "RightVectorBar;": '\U00002953',
+ "Rightarrow;": '\U000021D2',
+ "Ropf;": '\U0000211D',
+ "RoundImplies;": '\U00002970',
+ "Rrightarrow;": '\U000021DB',
+ "Rscr;": '\U0000211B',
+ "Rsh;": '\U000021B1',
+ "RuleDelayed;": '\U000029F4',
+ "SHCHcy;": '\U00000429',
+ "SHcy;": '\U00000428',
+ "SOFTcy;": '\U0000042C',
+ "Sacute;": '\U0000015A',
+ "Sc;": '\U00002ABC',
+ "Scaron;": '\U00000160',
+ "Scedil;": '\U0000015E',
+ "Scirc;": '\U0000015C',
+ "Scy;": '\U00000421',
+ "Sfr;": '\U0001D516',
+ "ShortDownArrow;": '\U00002193',
+ "ShortLeftArrow;": '\U00002190',
+ "ShortRightArrow;": '\U00002192',
+ "ShortUpArrow;": '\U00002191',
+ "Sigma;": '\U000003A3',
+ "SmallCircle;": '\U00002218',
+ "Sopf;": '\U0001D54A',
+ "Sqrt;": '\U0000221A',
+ "Square;": '\U000025A1',
+ "SquareIntersection;": '\U00002293',
+ "SquareSubset;": '\U0000228F',
+ "SquareSubsetEqual;": '\U00002291',
+ "SquareSuperset;": '\U00002290',
+ "SquareSupersetEqual;": '\U00002292',
+ "SquareUnion;": '\U00002294',
+ "Sscr;": '\U0001D4AE',
+ "Star;": '\U000022C6',
+ "Sub;": '\U000022D0',
+ "Subset;": '\U000022D0',
+ "SubsetEqual;": '\U00002286',
+ "Succeeds;": '\U0000227B',
+ "SucceedsEqual;": '\U00002AB0',
+ "SucceedsSlantEqual;": '\U0000227D',
+ "SucceedsTilde;": '\U0000227F',
+ "SuchThat;": '\U0000220B',
+ "Sum;": '\U00002211',
+ "Sup;": '\U000022D1',
+ "Superset;": '\U00002283',
+ "SupersetEqual;": '\U00002287',
+ "Supset;": '\U000022D1',
+ "THORN;": '\U000000DE',
+ "TRADE;": '\U00002122',
+ "TSHcy;": '\U0000040B',
+ "TScy;": '\U00000426',
+ "Tab;": '\U00000009',
+ "Tau;": '\U000003A4',
+ "Tcaron;": '\U00000164',
+ "Tcedil;": '\U00000162',
+ "Tcy;": '\U00000422',
+ "Tfr;": '\U0001D517',
+ "Therefore;": '\U00002234',
+ "Theta;": '\U00000398',
+ "ThinSpace;": '\U00002009',
+ "Tilde;": '\U0000223C',
+ "TildeEqual;": '\U00002243',
+ "TildeFullEqual;": '\U00002245',
+ "TildeTilde;": '\U00002248',
+ "Topf;": '\U0001D54B',
+ "TripleDot;": '\U000020DB',
+ "Tscr;": '\U0001D4AF',
+ "Tstrok;": '\U00000166',
+ "Uacute;": '\U000000DA',
+ "Uarr;": '\U0000219F',
+ "Uarrocir;": '\U00002949',
+ "Ubrcy;": '\U0000040E',
+ "Ubreve;": '\U0000016C',
+ "Ucirc;": '\U000000DB',
+ "Ucy;": '\U00000423',
+ "Udblac;": '\U00000170',
+ "Ufr;": '\U0001D518',
+ "Ugrave;": '\U000000D9',
+ "Umacr;": '\U0000016A',
+ "UnderBar;": '\U0000005F',
+ "UnderBrace;": '\U000023DF',
+ "UnderBracket;": '\U000023B5',
+ "UnderParenthesis;": '\U000023DD',
+ "Union;": '\U000022C3',
+ "UnionPlus;": '\U0000228E',
+ "Uogon;": '\U00000172',
+ "Uopf;": '\U0001D54C',
+ "UpArrow;": '\U00002191',
+ "UpArrowBar;": '\U00002912',
+ "UpArrowDownArrow;": '\U000021C5',
+ "UpDownArrow;": '\U00002195',
+ "UpEquilibrium;": '\U0000296E',
+ "UpTee;": '\U000022A5',
+ "UpTeeArrow;": '\U000021A5',
+ "Uparrow;": '\U000021D1',
+ "Updownarrow;": '\U000021D5',
+ "UpperLeftArrow;": '\U00002196',
+ "UpperRightArrow;": '\U00002197',
+ "Upsi;": '\U000003D2',
+ "Upsilon;": '\U000003A5',
+ "Uring;": '\U0000016E',
+ "Uscr;": '\U0001D4B0',
+ "Utilde;": '\U00000168',
+ "Uuml;": '\U000000DC',
+ "VDash;": '\U000022AB',
+ "Vbar;": '\U00002AEB',
+ "Vcy;": '\U00000412',
+ "Vdash;": '\U000022A9',
+ "Vdashl;": '\U00002AE6',
+ "Vee;": '\U000022C1',
+ "Verbar;": '\U00002016',
+ "Vert;": '\U00002016',
+ "VerticalBar;": '\U00002223',
+ "VerticalLine;": '\U0000007C',
+ "VerticalSeparator;": '\U00002758',
+ "VerticalTilde;": '\U00002240',
+ "VeryThinSpace;": '\U0000200A',
+ "Vfr;": '\U0001D519',
+ "Vopf;": '\U0001D54D',
+ "Vscr;": '\U0001D4B1',
+ "Vvdash;": '\U000022AA',
+ "Wcirc;": '\U00000174',
+ "Wedge;": '\U000022C0',
+ "Wfr;": '\U0001D51A',
+ "Wopf;": '\U0001D54E',
+ "Wscr;": '\U0001D4B2',
+ "Xfr;": '\U0001D51B',
+ "Xi;": '\U0000039E',
+ "Xopf;": '\U0001D54F',
+ "Xscr;": '\U0001D4B3',
+ "YAcy;": '\U0000042F',
+ "YIcy;": '\U00000407',
+ "YUcy;": '\U0000042E',
+ "Yacute;": '\U000000DD',
+ "Ycirc;": '\U00000176',
+ "Ycy;": '\U0000042B',
+ "Yfr;": '\U0001D51C',
+ "Yopf;": '\U0001D550',
+ "Yscr;": '\U0001D4B4',
+ "Yuml;": '\U00000178',
+ "ZHcy;": '\U00000416',
+ "Zacute;": '\U00000179',
+ "Zcaron;": '\U0000017D',
+ "Zcy;": '\U00000417',
+ "Zdot;": '\U0000017B',
+ "ZeroWidthSpace;": '\U0000200B',
+ "Zeta;": '\U00000396',
+ "Zfr;": '\U00002128',
+ "Zopf;": '\U00002124',
+ "Zscr;": '\U0001D4B5',
+ "aacute;": '\U000000E1',
+ "abreve;": '\U00000103',
+ "ac;": '\U0000223E',
+ "acd;": '\U0000223F',
+ "acirc;": '\U000000E2',
+ "acute;": '\U000000B4',
+ "acy;": '\U00000430',
+ "aelig;": '\U000000E6',
+ "af;": '\U00002061',
+ "afr;": '\U0001D51E',
+ "agrave;": '\U000000E0',
+ "alefsym;": '\U00002135',
+ "aleph;": '\U00002135',
+ "alpha;": '\U000003B1',
+ "amacr;": '\U00000101',
+ "amalg;": '\U00002A3F',
+ "amp;": '\U00000026',
+ "and;": '\U00002227',
+ "andand;": '\U00002A55',
+ "andd;": '\U00002A5C',
+ "andslope;": '\U00002A58',
+ "andv;": '\U00002A5A',
+ "ang;": '\U00002220',
+ "ange;": '\U000029A4',
+ "angle;": '\U00002220',
+ "angmsd;": '\U00002221',
+ "angmsdaa;": '\U000029A8',
+ "angmsdab;": '\U000029A9',
+ "angmsdac;": '\U000029AA',
+ "angmsdad;": '\U000029AB',
+ "angmsdae;": '\U000029AC',
+ "angmsdaf;": '\U000029AD',
+ "angmsdag;": '\U000029AE',
+ "angmsdah;": '\U000029AF',
+ "angrt;": '\U0000221F',
+ "angrtvb;": '\U000022BE',
+ "angrtvbd;": '\U0000299D',
+ "angsph;": '\U00002222',
+ "angst;": '\U000000C5',
+ "angzarr;": '\U0000237C',
+ "aogon;": '\U00000105',
+ "aopf;": '\U0001D552',
+ "ap;": '\U00002248',
+ "apE;": '\U00002A70',
+ "apacir;": '\U00002A6F',
+ "ape;": '\U0000224A',
+ "apid;": '\U0000224B',
+ "apos;": '\U00000027',
+ "approx;": '\U00002248',
+ "approxeq;": '\U0000224A',
+ "aring;": '\U000000E5',
+ "ascr;": '\U0001D4B6',
+ "ast;": '\U0000002A',
+ "asymp;": '\U00002248',
+ "asympeq;": '\U0000224D',
+ "atilde;": '\U000000E3',
+ "auml;": '\U000000E4',
+ "awconint;": '\U00002233',
+ "awint;": '\U00002A11',
+ "bNot;": '\U00002AED',
+ "backcong;": '\U0000224C',
+ "backepsilon;": '\U000003F6',
+ "backprime;": '\U00002035',
+ "backsim;": '\U0000223D',
+ "backsimeq;": '\U000022CD',
+ "barvee;": '\U000022BD',
+ "barwed;": '\U00002305',
+ "barwedge;": '\U00002305',
+ "bbrk;": '\U000023B5',
+ "bbrktbrk;": '\U000023B6',
+ "bcong;": '\U0000224C',
+ "bcy;": '\U00000431',
+ "bdquo;": '\U0000201E',
+ "becaus;": '\U00002235',
+ "because;": '\U00002235',
+ "bemptyv;": '\U000029B0',
+ "bepsi;": '\U000003F6',
+ "bernou;": '\U0000212C',
+ "beta;": '\U000003B2',
+ "beth;": '\U00002136',
+ "between;": '\U0000226C',
+ "bfr;": '\U0001D51F',
+ "bigcap;": '\U000022C2',
+ "bigcirc;": '\U000025EF',
+ "bigcup;": '\U000022C3',
+ "bigodot;": '\U00002A00',
+ "bigoplus;": '\U00002A01',
+ "bigotimes;": '\U00002A02',
+ "bigsqcup;": '\U00002A06',
+ "bigstar;": '\U00002605',
+ "bigtriangledown;": '\U000025BD',
+ "bigtriangleup;": '\U000025B3',
+ "biguplus;": '\U00002A04',
+ "bigvee;": '\U000022C1',
+ "bigwedge;": '\U000022C0',
+ "bkarow;": '\U0000290D',
+ "blacklozenge;": '\U000029EB',
+ "blacksquare;": '\U000025AA',
+ "blacktriangle;": '\U000025B4',
+ "blacktriangledown;": '\U000025BE',
+ "blacktriangleleft;": '\U000025C2',
+ "blacktriangleright;": '\U000025B8',
+ "blank;": '\U00002423',
+ "blk12;": '\U00002592',
+ "blk14;": '\U00002591',
+ "blk34;": '\U00002593',
+ "block;": '\U00002588',
+ "bnot;": '\U00002310',
+ "bopf;": '\U0001D553',
+ "bot;": '\U000022A5',
+ "bottom;": '\U000022A5',
+ "bowtie;": '\U000022C8',
+ "boxDL;": '\U00002557',
+ "boxDR;": '\U00002554',
+ "boxDl;": '\U00002556',
+ "boxDr;": '\U00002553',
+ "boxH;": '\U00002550',
+ "boxHD;": '\U00002566',
+ "boxHU;": '\U00002569',
+ "boxHd;": '\U00002564',
+ "boxHu;": '\U00002567',
+ "boxUL;": '\U0000255D',
+ "boxUR;": '\U0000255A',
+ "boxUl;": '\U0000255C',
+ "boxUr;": '\U00002559',
+ "boxV;": '\U00002551',
+ "boxVH;": '\U0000256C',
+ "boxVL;": '\U00002563',
+ "boxVR;": '\U00002560',
+ "boxVh;": '\U0000256B',
+ "boxVl;": '\U00002562',
+ "boxVr;": '\U0000255F',
+ "boxbox;": '\U000029C9',
+ "boxdL;": '\U00002555',
+ "boxdR;": '\U00002552',
+ "boxdl;": '\U00002510',
+ "boxdr;": '\U0000250C',
+ "boxh;": '\U00002500',
+ "boxhD;": '\U00002565',
+ "boxhU;": '\U00002568',
+ "boxhd;": '\U0000252C',
+ "boxhu;": '\U00002534',
+ "boxminus;": '\U0000229F',
+ "boxplus;": '\U0000229E',
+ "boxtimes;": '\U000022A0',
+ "boxuL;": '\U0000255B',
+ "boxuR;": '\U00002558',
+ "boxul;": '\U00002518',
+ "boxur;": '\U00002514',
+ "boxv;": '\U00002502',
+ "boxvH;": '\U0000256A',
+ "boxvL;": '\U00002561',
+ "boxvR;": '\U0000255E',
+ "boxvh;": '\U0000253C',
+ "boxvl;": '\U00002524',
+ "boxvr;": '\U0000251C',
+ "bprime;": '\U00002035',
+ "breve;": '\U000002D8',
+ "brvbar;": '\U000000A6',
+ "bscr;": '\U0001D4B7',
+ "bsemi;": '\U0000204F',
+ "bsim;": '\U0000223D',
+ "bsime;": '\U000022CD',
+ "bsol;": '\U0000005C',
+ "bsolb;": '\U000029C5',
+ "bsolhsub;": '\U000027C8',
+ "bull;": '\U00002022',
+ "bullet;": '\U00002022',
+ "bump;": '\U0000224E',
+ "bumpE;": '\U00002AAE',
+ "bumpe;": '\U0000224F',
+ "bumpeq;": '\U0000224F',
+ "cacute;": '\U00000107',
+ "cap;": '\U00002229',
+ "capand;": '\U00002A44',
+ "capbrcup;": '\U00002A49',
+ "capcap;": '\U00002A4B',
+ "capcup;": '\U00002A47',
+ "capdot;": '\U00002A40',
+ "caret;": '\U00002041',
+ "caron;": '\U000002C7',
+ "ccaps;": '\U00002A4D',
+ "ccaron;": '\U0000010D',
+ "ccedil;": '\U000000E7',
+ "ccirc;": '\U00000109',
+ "ccups;": '\U00002A4C',
+ "ccupssm;": '\U00002A50',
+ "cdot;": '\U0000010B',
+ "cedil;": '\U000000B8',
+ "cemptyv;": '\U000029B2',
+ "cent;": '\U000000A2',
+ "centerdot;": '\U000000B7',
+ "cfr;": '\U0001D520',
+ "chcy;": '\U00000447',
+ "check;": '\U00002713',
+ "checkmark;": '\U00002713',
+ "chi;": '\U000003C7',
+ "cir;": '\U000025CB',
+ "cirE;": '\U000029C3',
+ "circ;": '\U000002C6',
+ "circeq;": '\U00002257',
+ "circlearrowleft;": '\U000021BA',
+ "circlearrowright;": '\U000021BB',
+ "circledR;": '\U000000AE',
+ "circledS;": '\U000024C8',
+ "circledast;": '\U0000229B',
+ "circledcirc;": '\U0000229A',
+ "circleddash;": '\U0000229D',
+ "cire;": '\U00002257',
+ "cirfnint;": '\U00002A10',
+ "cirmid;": '\U00002AEF',
+ "cirscir;": '\U000029C2',
+ "clubs;": '\U00002663',
+ "clubsuit;": '\U00002663',
+ "colon;": '\U0000003A',
+ "colone;": '\U00002254',
+ "coloneq;": '\U00002254',
+ "comma;": '\U0000002C',
+ "commat;": '\U00000040',
+ "comp;": '\U00002201',
+ "compfn;": '\U00002218',
+ "complement;": '\U00002201',
+ "complexes;": '\U00002102',
+ "cong;": '\U00002245',
+ "congdot;": '\U00002A6D',
+ "conint;": '\U0000222E',
+ "copf;": '\U0001D554',
+ "coprod;": '\U00002210',
+ "copy;": '\U000000A9',
+ "copysr;": '\U00002117',
+ "crarr;": '\U000021B5',
+ "cross;": '\U00002717',
+ "cscr;": '\U0001D4B8',
+ "csub;": '\U00002ACF',
+ "csube;": '\U00002AD1',
+ "csup;": '\U00002AD0',
+ "csupe;": '\U00002AD2',
+ "ctdot;": '\U000022EF',
+ "cudarrl;": '\U00002938',
+ "cudarrr;": '\U00002935',
+ "cuepr;": '\U000022DE',
+ "cuesc;": '\U000022DF',
+ "cularr;": '\U000021B6',
+ "cularrp;": '\U0000293D',
+ "cup;": '\U0000222A',
+ "cupbrcap;": '\U00002A48',
+ "cupcap;": '\U00002A46',
+ "cupcup;": '\U00002A4A',
+ "cupdot;": '\U0000228D',
+ "cupor;": '\U00002A45',
+ "curarr;": '\U000021B7',
+ "curarrm;": '\U0000293C',
+ "curlyeqprec;": '\U000022DE',
+ "curlyeqsucc;": '\U000022DF',
+ "curlyvee;": '\U000022CE',
+ "curlywedge;": '\U000022CF',
+ "curren;": '\U000000A4',
+ "curvearrowleft;": '\U000021B6',
+ "curvearrowright;": '\U000021B7',
+ "cuvee;": '\U000022CE',
+ "cuwed;": '\U000022CF',
+ "cwconint;": '\U00002232',
+ "cwint;": '\U00002231',
+ "cylcty;": '\U0000232D',
+ "dArr;": '\U000021D3',
+ "dHar;": '\U00002965',
+ "dagger;": '\U00002020',
+ "daleth;": '\U00002138',
+ "darr;": '\U00002193',
+ "dash;": '\U00002010',
+ "dashv;": '\U000022A3',
+ "dbkarow;": '\U0000290F',
+ "dblac;": '\U000002DD',
+ "dcaron;": '\U0000010F',
+ "dcy;": '\U00000434',
+ "dd;": '\U00002146',
+ "ddagger;": '\U00002021',
+ "ddarr;": '\U000021CA',
+ "ddotseq;": '\U00002A77',
+ "deg;": '\U000000B0',
+ "delta;": '\U000003B4',
+ "demptyv;": '\U000029B1',
+ "dfisht;": '\U0000297F',
+ "dfr;": '\U0001D521',
+ "dharl;": '\U000021C3',
+ "dharr;": '\U000021C2',
+ "diam;": '\U000022C4',
+ "diamond;": '\U000022C4',
+ "diamondsuit;": '\U00002666',
+ "diams;": '\U00002666',
+ "die;": '\U000000A8',
+ "digamma;": '\U000003DD',
+ "disin;": '\U000022F2',
+ "div;": '\U000000F7',
+ "divide;": '\U000000F7',
+ "divideontimes;": '\U000022C7',
+ "divonx;": '\U000022C7',
+ "djcy;": '\U00000452',
+ "dlcorn;": '\U0000231E',
+ "dlcrop;": '\U0000230D',
+ "dollar;": '\U00000024',
+ "dopf;": '\U0001D555',
+ "dot;": '\U000002D9',
+ "doteq;": '\U00002250',
+ "doteqdot;": '\U00002251',
+ "dotminus;": '\U00002238',
+ "dotplus;": '\U00002214',
+ "dotsquare;": '\U000022A1',
+ "doublebarwedge;": '\U00002306',
+ "downarrow;": '\U00002193',
+ "downdownarrows;": '\U000021CA',
+ "downharpoonleft;": '\U000021C3',
+ "downharpoonright;": '\U000021C2',
+ "drbkarow;": '\U00002910',
+ "drcorn;": '\U0000231F',
+ "drcrop;": '\U0000230C',
+ "dscr;": '\U0001D4B9',
+ "dscy;": '\U00000455',
+ "dsol;": '\U000029F6',
+ "dstrok;": '\U00000111',
+ "dtdot;": '\U000022F1',
+ "dtri;": '\U000025BF',
+ "dtrif;": '\U000025BE',
+ "duarr;": '\U000021F5',
+ "duhar;": '\U0000296F',
+ "dwangle;": '\U000029A6',
+ "dzcy;": '\U0000045F',
+ "dzigrarr;": '\U000027FF',
+ "eDDot;": '\U00002A77',
+ "eDot;": '\U00002251',
+ "eacute;": '\U000000E9',
+ "easter;": '\U00002A6E',
+ "ecaron;": '\U0000011B',
+ "ecir;": '\U00002256',
+ "ecirc;": '\U000000EA',
+ "ecolon;": '\U00002255',
+ "ecy;": '\U0000044D',
+ "edot;": '\U00000117',
+ "ee;": '\U00002147',
+ "efDot;": '\U00002252',
+ "efr;": '\U0001D522',
+ "eg;": '\U00002A9A',
+ "egrave;": '\U000000E8',
+ "egs;": '\U00002A96',
+ "egsdot;": '\U00002A98',
+ "el;": '\U00002A99',
+ "elinters;": '\U000023E7',
+ "ell;": '\U00002113',
+ "els;": '\U00002A95',
+ "elsdot;": '\U00002A97',
+ "emacr;": '\U00000113',
+ "empty;": '\U00002205',
+ "emptyset;": '\U00002205',
+ "emptyv;": '\U00002205',
+ "emsp;": '\U00002003',
+ "emsp13;": '\U00002004',
+ "emsp14;": '\U00002005',
+ "eng;": '\U0000014B',
+ "ensp;": '\U00002002',
+ "eogon;": '\U00000119',
+ "eopf;": '\U0001D556',
+ "epar;": '\U000022D5',
+ "eparsl;": '\U000029E3',
+ "eplus;": '\U00002A71',
+ "epsi;": '\U000003B5',
+ "epsilon;": '\U000003B5',
+ "epsiv;": '\U000003F5',
+ "eqcirc;": '\U00002256',
+ "eqcolon;": '\U00002255',
+ "eqsim;": '\U00002242',
+ "eqslantgtr;": '\U00002A96',
+ "eqslantless;": '\U00002A95',
+ "equals;": '\U0000003D',
+ "equest;": '\U0000225F',
+ "equiv;": '\U00002261',
+ "equivDD;": '\U00002A78',
+ "eqvparsl;": '\U000029E5',
+ "erDot;": '\U00002253',
+ "erarr;": '\U00002971',
+ "escr;": '\U0000212F',
+ "esdot;": '\U00002250',
+ "esim;": '\U00002242',
+ "eta;": '\U000003B7',
+ "eth;": '\U000000F0',
+ "euml;": '\U000000EB',
+ "euro;": '\U000020AC',
+ "excl;": '\U00000021',
+ "exist;": '\U00002203',
+ "expectation;": '\U00002130',
+ "exponentiale;": '\U00002147',
+ "fallingdotseq;": '\U00002252',
+ "fcy;": '\U00000444',
+ "female;": '\U00002640',
+ "ffilig;": '\U0000FB03',
+ "fflig;": '\U0000FB00',
+ "ffllig;": '\U0000FB04',
+ "ffr;": '\U0001D523',
+ "filig;": '\U0000FB01',
+ "flat;": '\U0000266D',
+ "fllig;": '\U0000FB02',
+ "fltns;": '\U000025B1',
+ "fnof;": '\U00000192',
+ "fopf;": '\U0001D557',
+ "forall;": '\U00002200',
+ "fork;": '\U000022D4',
+ "forkv;": '\U00002AD9',
+ "fpartint;": '\U00002A0D',
+ "frac12;": '\U000000BD',
+ "frac13;": '\U00002153',
+ "frac14;": '\U000000BC',
+ "frac15;": '\U00002155',
+ "frac16;": '\U00002159',
+ "frac18;": '\U0000215B',
+ "frac23;": '\U00002154',
+ "frac25;": '\U00002156',
+ "frac34;": '\U000000BE',
+ "frac35;": '\U00002157',
+ "frac38;": '\U0000215C',
+ "frac45;": '\U00002158',
+ "frac56;": '\U0000215A',
+ "frac58;": '\U0000215D',
+ "frac78;": '\U0000215E',
+ "frasl;": '\U00002044',
+ "frown;": '\U00002322',
+ "fscr;": '\U0001D4BB',
+ "gE;": '\U00002267',
+ "gEl;": '\U00002A8C',
+ "gacute;": '\U000001F5',
+ "gamma;": '\U000003B3',
+ "gammad;": '\U000003DD',
+ "gap;": '\U00002A86',
+ "gbreve;": '\U0000011F',
+ "gcirc;": '\U0000011D',
+ "gcy;": '\U00000433',
+ "gdot;": '\U00000121',
+ "ge;": '\U00002265',
+ "gel;": '\U000022DB',
+ "geq;": '\U00002265',
+ "geqq;": '\U00002267',
+ "geqslant;": '\U00002A7E',
+ "ges;": '\U00002A7E',
+ "gescc;": '\U00002AA9',
+ "gesdot;": '\U00002A80',
+ "gesdoto;": '\U00002A82',
+ "gesdotol;": '\U00002A84',
+ "gesles;": '\U00002A94',
+ "gfr;": '\U0001D524',
+ "gg;": '\U0000226B',
+ "ggg;": '\U000022D9',
+ "gimel;": '\U00002137',
+ "gjcy;": '\U00000453',
+ "gl;": '\U00002277',
+ "glE;": '\U00002A92',
+ "gla;": '\U00002AA5',
+ "glj;": '\U00002AA4',
+ "gnE;": '\U00002269',
+ "gnap;": '\U00002A8A',
+ "gnapprox;": '\U00002A8A',
+ "gne;": '\U00002A88',
+ "gneq;": '\U00002A88',
+ "gneqq;": '\U00002269',
+ "gnsim;": '\U000022E7',
+ "gopf;": '\U0001D558',
+ "grave;": '\U00000060',
+ "gscr;": '\U0000210A',
+ "gsim;": '\U00002273',
+ "gsime;": '\U00002A8E',
+ "gsiml;": '\U00002A90',
+ "gt;": '\U0000003E',
+ "gtcc;": '\U00002AA7',
+ "gtcir;": '\U00002A7A',
+ "gtdot;": '\U000022D7',
+ "gtlPar;": '\U00002995',
+ "gtquest;": '\U00002A7C',
+ "gtrapprox;": '\U00002A86',
+ "gtrarr;": '\U00002978',
+ "gtrdot;": '\U000022D7',
+ "gtreqless;": '\U000022DB',
+ "gtreqqless;": '\U00002A8C',
+ "gtrless;": '\U00002277',
+ "gtrsim;": '\U00002273',
+ "hArr;": '\U000021D4',
+ "hairsp;": '\U0000200A',
+ "half;": '\U000000BD',
+ "hamilt;": '\U0000210B',
+ "hardcy;": '\U0000044A',
+ "harr;": '\U00002194',
+ "harrcir;": '\U00002948',
+ "harrw;": '\U000021AD',
+ "hbar;": '\U0000210F',
+ "hcirc;": '\U00000125',
+ "hearts;": '\U00002665',
+ "heartsuit;": '\U00002665',
+ "hellip;": '\U00002026',
+ "hercon;": '\U000022B9',
+ "hfr;": '\U0001D525',
+ "hksearow;": '\U00002925',
+ "hkswarow;": '\U00002926',
+ "hoarr;": '\U000021FF',
+ "homtht;": '\U0000223B',
+ "hookleftarrow;": '\U000021A9',
+ "hookrightarrow;": '\U000021AA',
+ "hopf;": '\U0001D559',
+ "horbar;": '\U00002015',
+ "hscr;": '\U0001D4BD',
+ "hslash;": '\U0000210F',
+ "hstrok;": '\U00000127',
+ "hybull;": '\U00002043',
+ "hyphen;": '\U00002010',
+ "iacute;": '\U000000ED',
+ "ic;": '\U00002063',
+ "icirc;": '\U000000EE',
+ "icy;": '\U00000438',
+ "iecy;": '\U00000435',
+ "iexcl;": '\U000000A1',
+ "iff;": '\U000021D4',
+ "ifr;": '\U0001D526',
+ "igrave;": '\U000000EC',
+ "ii;": '\U00002148',
+ "iiiint;": '\U00002A0C',
+ "iiint;": '\U0000222D',
+ "iinfin;": '\U000029DC',
+ "iiota;": '\U00002129',
+ "ijlig;": '\U00000133',
+ "imacr;": '\U0000012B',
+ "image;": '\U00002111',
+ "imagline;": '\U00002110',
+ "imagpart;": '\U00002111',
+ "imath;": '\U00000131',
+ "imof;": '\U000022B7',
+ "imped;": '\U000001B5',
+ "in;": '\U00002208',
+ "incare;": '\U00002105',
+ "infin;": '\U0000221E',
+ "infintie;": '\U000029DD',
+ "inodot;": '\U00000131',
+ "int;": '\U0000222B',
+ "intcal;": '\U000022BA',
+ "integers;": '\U00002124',
+ "intercal;": '\U000022BA',
+ "intlarhk;": '\U00002A17',
+ "intprod;": '\U00002A3C',
+ "iocy;": '\U00000451',
+ "iogon;": '\U0000012F',
+ "iopf;": '\U0001D55A',
+ "iota;": '\U000003B9',
+ "iprod;": '\U00002A3C',
+ "iquest;": '\U000000BF',
+ "iscr;": '\U0001D4BE',
+ "isin;": '\U00002208',
+ "isinE;": '\U000022F9',
+ "isindot;": '\U000022F5',
+ "isins;": '\U000022F4',
+ "isinsv;": '\U000022F3',
+ "isinv;": '\U00002208',
+ "it;": '\U00002062',
+ "itilde;": '\U00000129',
+ "iukcy;": '\U00000456',
+ "iuml;": '\U000000EF',
+ "jcirc;": '\U00000135',
+ "jcy;": '\U00000439',
+ "jfr;": '\U0001D527',
+ "jmath;": '\U00000237',
+ "jopf;": '\U0001D55B',
+ "jscr;": '\U0001D4BF',
+ "jsercy;": '\U00000458',
+ "jukcy;": '\U00000454',
+ "kappa;": '\U000003BA',
+ "kappav;": '\U000003F0',
+ "kcedil;": '\U00000137',
+ "kcy;": '\U0000043A',
+ "kfr;": '\U0001D528',
+ "kgreen;": '\U00000138',
+ "khcy;": '\U00000445',
+ "kjcy;": '\U0000045C',
+ "kopf;": '\U0001D55C',
+ "kscr;": '\U0001D4C0',
+ "lAarr;": '\U000021DA',
+ "lArr;": '\U000021D0',
+ "lAtail;": '\U0000291B',
+ "lBarr;": '\U0000290E',
+ "lE;": '\U00002266',
+ "lEg;": '\U00002A8B',
+ "lHar;": '\U00002962',
+ "lacute;": '\U0000013A',
+ "laemptyv;": '\U000029B4',
+ "lagran;": '\U00002112',
+ "lambda;": '\U000003BB',
+ "lang;": '\U000027E8',
+ "langd;": '\U00002991',
+ "langle;": '\U000027E8',
+ "lap;": '\U00002A85',
+ "laquo;": '\U000000AB',
+ "larr;": '\U00002190',
+ "larrb;": '\U000021E4',
+ "larrbfs;": '\U0000291F',
+ "larrfs;": '\U0000291D',
+ "larrhk;": '\U000021A9',
+ "larrlp;": '\U000021AB',
+ "larrpl;": '\U00002939',
+ "larrsim;": '\U00002973',
+ "larrtl;": '\U000021A2',
+ "lat;": '\U00002AAB',
+ "latail;": '\U00002919',
+ "late;": '\U00002AAD',
+ "lbarr;": '\U0000290C',
+ "lbbrk;": '\U00002772',
+ "lbrace;": '\U0000007B',
+ "lbrack;": '\U0000005B',
+ "lbrke;": '\U0000298B',
+ "lbrksld;": '\U0000298F',
+ "lbrkslu;": '\U0000298D',
+ "lcaron;": '\U0000013E',
+ "lcedil;": '\U0000013C',
+ "lceil;": '\U00002308',
+ "lcub;": '\U0000007B',
+ "lcy;": '\U0000043B',
+ "ldca;": '\U00002936',
+ "ldquo;": '\U0000201C',
+ "ldquor;": '\U0000201E',
+ "ldrdhar;": '\U00002967',
+ "ldrushar;": '\U0000294B',
+ "ldsh;": '\U000021B2',
+ "le;": '\U00002264',
+ "leftarrow;": '\U00002190',
+ "leftarrowtail;": '\U000021A2',
+ "leftharpoondown;": '\U000021BD',
+ "leftharpoonup;": '\U000021BC',
+ "leftleftarrows;": '\U000021C7',
+ "leftrightarrow;": '\U00002194',
+ "leftrightarrows;": '\U000021C6',
+ "leftrightharpoons;": '\U000021CB',
+ "leftrightsquigarrow;": '\U000021AD',
+ "leftthreetimes;": '\U000022CB',
+ "leg;": '\U000022DA',
+ "leq;": '\U00002264',
+ "leqq;": '\U00002266',
+ "leqslant;": '\U00002A7D',
+ "les;": '\U00002A7D',
+ "lescc;": '\U00002AA8',
+ "lesdot;": '\U00002A7F',
+ "lesdoto;": '\U00002A81',
+ "lesdotor;": '\U00002A83',
+ "lesges;": '\U00002A93',
+ "lessapprox;": '\U00002A85',
+ "lessdot;": '\U000022D6',
+ "lesseqgtr;": '\U000022DA',
+ "lesseqqgtr;": '\U00002A8B',
+ "lessgtr;": '\U00002276',
+ "lesssim;": '\U00002272',
+ "lfisht;": '\U0000297C',
+ "lfloor;": '\U0000230A',
+ "lfr;": '\U0001D529',
+ "lg;": '\U00002276',
+ "lgE;": '\U00002A91',
+ "lhard;": '\U000021BD',
+ "lharu;": '\U000021BC',
+ "lharul;": '\U0000296A',
+ "lhblk;": '\U00002584',
+ "ljcy;": '\U00000459',
+ "ll;": '\U0000226A',
+ "llarr;": '\U000021C7',
+ "llcorner;": '\U0000231E',
+ "llhard;": '\U0000296B',
+ "lltri;": '\U000025FA',
+ "lmidot;": '\U00000140',
+ "lmoust;": '\U000023B0',
+ "lmoustache;": '\U000023B0',
+ "lnE;": '\U00002268',
+ "lnap;": '\U00002A89',
+ "lnapprox;": '\U00002A89',
+ "lne;": '\U00002A87',
+ "lneq;": '\U00002A87',
+ "lneqq;": '\U00002268',
+ "lnsim;": '\U000022E6',
+ "loang;": '\U000027EC',
+ "loarr;": '\U000021FD',
+ "lobrk;": '\U000027E6',
+ "longleftarrow;": '\U000027F5',
+ "longleftrightarrow;": '\U000027F7',
+ "longmapsto;": '\U000027FC',
+ "longrightarrow;": '\U000027F6',
+ "looparrowleft;": '\U000021AB',
+ "looparrowright;": '\U000021AC',
+ "lopar;": '\U00002985',
+ "lopf;": '\U0001D55D',
+ "loplus;": '\U00002A2D',
+ "lotimes;": '\U00002A34',
+ "lowast;": '\U00002217',
+ "lowbar;": '\U0000005F',
+ "loz;": '\U000025CA',
+ "lozenge;": '\U000025CA',
+ "lozf;": '\U000029EB',
+ "lpar;": '\U00000028',
+ "lparlt;": '\U00002993',
+ "lrarr;": '\U000021C6',
+ "lrcorner;": '\U0000231F',
+ "lrhar;": '\U000021CB',
+ "lrhard;": '\U0000296D',
+ "lrm;": '\U0000200E',
+ "lrtri;": '\U000022BF',
+ "lsaquo;": '\U00002039',
+ "lscr;": '\U0001D4C1',
+ "lsh;": '\U000021B0',
+ "lsim;": '\U00002272',
+ "lsime;": '\U00002A8D',
+ "lsimg;": '\U00002A8F',
+ "lsqb;": '\U0000005B',
+ "lsquo;": '\U00002018',
+ "lsquor;": '\U0000201A',
+ "lstrok;": '\U00000142',
+ "lt;": '\U0000003C',
+ "ltcc;": '\U00002AA6',
+ "ltcir;": '\U00002A79',
+ "ltdot;": '\U000022D6',
+ "lthree;": '\U000022CB',
+ "ltimes;": '\U000022C9',
+ "ltlarr;": '\U00002976',
+ "ltquest;": '\U00002A7B',
+ "ltrPar;": '\U00002996',
+ "ltri;": '\U000025C3',
+ "ltrie;": '\U000022B4',
+ "ltrif;": '\U000025C2',
+ "lurdshar;": '\U0000294A',
+ "luruhar;": '\U00002966',
+ "mDDot;": '\U0000223A',
+ "macr;": '\U000000AF',
+ "male;": '\U00002642',
+ "malt;": '\U00002720',
+ "maltese;": '\U00002720',
+ "map;": '\U000021A6',
+ "mapsto;": '\U000021A6',
+ "mapstodown;": '\U000021A7',
+ "mapstoleft;": '\U000021A4',
+ "mapstoup;": '\U000021A5',
+ "marker;": '\U000025AE',
+ "mcomma;": '\U00002A29',
+ "mcy;": '\U0000043C',
+ "mdash;": '\U00002014',
+ "measuredangle;": '\U00002221',
+ "mfr;": '\U0001D52A',
+ "mho;": '\U00002127',
+ "micro;": '\U000000B5',
+ "mid;": '\U00002223',
+ "midast;": '\U0000002A',
+ "midcir;": '\U00002AF0',
+ "middot;": '\U000000B7',
+ "minus;": '\U00002212',
+ "minusb;": '\U0000229F',
+ "minusd;": '\U00002238',
+ "minusdu;": '\U00002A2A',
+ "mlcp;": '\U00002ADB',
+ "mldr;": '\U00002026',
+ "mnplus;": '\U00002213',
+ "models;": '\U000022A7',
+ "mopf;": '\U0001D55E',
+ "mp;": '\U00002213',
+ "mscr;": '\U0001D4C2',
+ "mstpos;": '\U0000223E',
+ "mu;": '\U000003BC',
+ "multimap;": '\U000022B8',
+ "mumap;": '\U000022B8',
+ "nLeftarrow;": '\U000021CD',
+ "nLeftrightarrow;": '\U000021CE',
+ "nRightarrow;": '\U000021CF',
+ "nVDash;": '\U000022AF',
+ "nVdash;": '\U000022AE',
+ "nabla;": '\U00002207',
+ "nacute;": '\U00000144',
+ "nap;": '\U00002249',
+ "napos;": '\U00000149',
+ "napprox;": '\U00002249',
+ "natur;": '\U0000266E',
+ "natural;": '\U0000266E',
+ "naturals;": '\U00002115',
+ "nbsp;": '\U000000A0',
+ "ncap;": '\U00002A43',
+ "ncaron;": '\U00000148',
+ "ncedil;": '\U00000146',
+ "ncong;": '\U00002247',
+ "ncup;": '\U00002A42',
+ "ncy;": '\U0000043D',
+ "ndash;": '\U00002013',
+ "ne;": '\U00002260',
+ "neArr;": '\U000021D7',
+ "nearhk;": '\U00002924',
+ "nearr;": '\U00002197',
+ "nearrow;": '\U00002197',
+ "nequiv;": '\U00002262',
+ "nesear;": '\U00002928',
+ "nexist;": '\U00002204',
+ "nexists;": '\U00002204',
+ "nfr;": '\U0001D52B',
+ "nge;": '\U00002271',
+ "ngeq;": '\U00002271',
+ "ngsim;": '\U00002275',
+ "ngt;": '\U0000226F',
+ "ngtr;": '\U0000226F',
+ "nhArr;": '\U000021CE',
+ "nharr;": '\U000021AE',
+ "nhpar;": '\U00002AF2',
+ "ni;": '\U0000220B',
+ "nis;": '\U000022FC',
+ "nisd;": '\U000022FA',
+ "niv;": '\U0000220B',
+ "njcy;": '\U0000045A',
+ "nlArr;": '\U000021CD',
+ "nlarr;": '\U0000219A',
+ "nldr;": '\U00002025',
+ "nle;": '\U00002270',
+ "nleftarrow;": '\U0000219A',
+ "nleftrightarrow;": '\U000021AE',
+ "nleq;": '\U00002270',
+ "nless;": '\U0000226E',
+ "nlsim;": '\U00002274',
+ "nlt;": '\U0000226E',
+ "nltri;": '\U000022EA',
+ "nltrie;": '\U000022EC',
+ "nmid;": '\U00002224',
+ "nopf;": '\U0001D55F',
+ "not;": '\U000000AC',
+ "notin;": '\U00002209',
+ "notinva;": '\U00002209',
+ "notinvb;": '\U000022F7',
+ "notinvc;": '\U000022F6',
+ "notni;": '\U0000220C',
+ "notniva;": '\U0000220C',
+ "notnivb;": '\U000022FE',
+ "notnivc;": '\U000022FD',
+ "npar;": '\U00002226',
+ "nparallel;": '\U00002226',
+ "npolint;": '\U00002A14',
+ "npr;": '\U00002280',
+ "nprcue;": '\U000022E0',
+ "nprec;": '\U00002280',
+ "nrArr;": '\U000021CF',
+ "nrarr;": '\U0000219B',
+ "nrightarrow;": '\U0000219B',
+ "nrtri;": '\U000022EB',
+ "nrtrie;": '\U000022ED',
+ "nsc;": '\U00002281',
+ "nsccue;": '\U000022E1',
+ "nscr;": '\U0001D4C3',
+ "nshortmid;": '\U00002224',
+ "nshortparallel;": '\U00002226',
+ "nsim;": '\U00002241',
+ "nsime;": '\U00002244',
+ "nsimeq;": '\U00002244',
+ "nsmid;": '\U00002224',
+ "nspar;": '\U00002226',
+ "nsqsube;": '\U000022E2',
+ "nsqsupe;": '\U000022E3',
+ "nsub;": '\U00002284',
+ "nsube;": '\U00002288',
+ "nsubseteq;": '\U00002288',
+ "nsucc;": '\U00002281',
+ "nsup;": '\U00002285',
+ "nsupe;": '\U00002289',
+ "nsupseteq;": '\U00002289',
+ "ntgl;": '\U00002279',
+ "ntilde;": '\U000000F1',
+ "ntlg;": '\U00002278',
+ "ntriangleleft;": '\U000022EA',
+ "ntrianglelefteq;": '\U000022EC',
+ "ntriangleright;": '\U000022EB',
+ "ntrianglerighteq;": '\U000022ED',
+ "nu;": '\U000003BD',
+ "num;": '\U00000023',
+ "numero;": '\U00002116',
+ "numsp;": '\U00002007',
+ "nvDash;": '\U000022AD',
+ "nvHarr;": '\U00002904',
+ "nvdash;": '\U000022AC',
+ "nvinfin;": '\U000029DE',
+ "nvlArr;": '\U00002902',
+ "nvrArr;": '\U00002903',
+ "nwArr;": '\U000021D6',
+ "nwarhk;": '\U00002923',
+ "nwarr;": '\U00002196',
+ "nwarrow;": '\U00002196',
+ "nwnear;": '\U00002927',
+ "oS;": '\U000024C8',
+ "oacute;": '\U000000F3',
+ "oast;": '\U0000229B',
+ "ocir;": '\U0000229A',
+ "ocirc;": '\U000000F4',
+ "ocy;": '\U0000043E',
+ "odash;": '\U0000229D',
+ "odblac;": '\U00000151',
+ "odiv;": '\U00002A38',
+ "odot;": '\U00002299',
+ "odsold;": '\U000029BC',
+ "oelig;": '\U00000153',
+ "ofcir;": '\U000029BF',
+ "ofr;": '\U0001D52C',
+ "ogon;": '\U000002DB',
+ "ograve;": '\U000000F2',
+ "ogt;": '\U000029C1',
+ "ohbar;": '\U000029B5',
+ "ohm;": '\U000003A9',
+ "oint;": '\U0000222E',
+ "olarr;": '\U000021BA',
+ "olcir;": '\U000029BE',
+ "olcross;": '\U000029BB',
+ "oline;": '\U0000203E',
+ "olt;": '\U000029C0',
+ "omacr;": '\U0000014D',
+ "omega;": '\U000003C9',
+ "omicron;": '\U000003BF',
+ "omid;": '\U000029B6',
+ "ominus;": '\U00002296',
+ "oopf;": '\U0001D560',
+ "opar;": '\U000029B7',
+ "operp;": '\U000029B9',
+ "oplus;": '\U00002295',
+ "or;": '\U00002228',
+ "orarr;": '\U000021BB',
+ "ord;": '\U00002A5D',
+ "order;": '\U00002134',
+ "orderof;": '\U00002134',
+ "ordf;": '\U000000AA',
+ "ordm;": '\U000000BA',
+ "origof;": '\U000022B6',
+ "oror;": '\U00002A56',
+ "orslope;": '\U00002A57',
+ "orv;": '\U00002A5B',
+ "oscr;": '\U00002134',
+ "oslash;": '\U000000F8',
+ "osol;": '\U00002298',
+ "otilde;": '\U000000F5',
+ "otimes;": '\U00002297',
+ "otimesas;": '\U00002A36',
+ "ouml;": '\U000000F6',
+ "ovbar;": '\U0000233D',
+ "par;": '\U00002225',
+ "para;": '\U000000B6',
+ "parallel;": '\U00002225',
+ "parsim;": '\U00002AF3',
+ "parsl;": '\U00002AFD',
+ "part;": '\U00002202',
+ "pcy;": '\U0000043F',
+ "percnt;": '\U00000025',
+ "period;": '\U0000002E',
+ "permil;": '\U00002030',
+ "perp;": '\U000022A5',
+ "pertenk;": '\U00002031',
+ "pfr;": '\U0001D52D',
+ "phi;": '\U000003C6',
+ "phiv;": '\U000003D5',
+ "phmmat;": '\U00002133',
+ "phone;": '\U0000260E',
+ "pi;": '\U000003C0',
+ "pitchfork;": '\U000022D4',
+ "piv;": '\U000003D6',
+ "planck;": '\U0000210F',
+ "planckh;": '\U0000210E',
+ "plankv;": '\U0000210F',
+ "plus;": '\U0000002B',
+ "plusacir;": '\U00002A23',
+ "plusb;": '\U0000229E',
+ "pluscir;": '\U00002A22',
+ "plusdo;": '\U00002214',
+ "plusdu;": '\U00002A25',
+ "pluse;": '\U00002A72',
+ "plusmn;": '\U000000B1',
+ "plussim;": '\U00002A26',
+ "plustwo;": '\U00002A27',
+ "pm;": '\U000000B1',
+ "pointint;": '\U00002A15',
+ "popf;": '\U0001D561',
+ "pound;": '\U000000A3',
+ "pr;": '\U0000227A',
+ "prE;": '\U00002AB3',
+ "prap;": '\U00002AB7',
+ "prcue;": '\U0000227C',
+ "pre;": '\U00002AAF',
+ "prec;": '\U0000227A',
+ "precapprox;": '\U00002AB7',
+ "preccurlyeq;": '\U0000227C',
+ "preceq;": '\U00002AAF',
+ "precnapprox;": '\U00002AB9',
+ "precneqq;": '\U00002AB5',
+ "precnsim;": '\U000022E8',
+ "precsim;": '\U0000227E',
+ "prime;": '\U00002032',
+ "primes;": '\U00002119',
+ "prnE;": '\U00002AB5',
+ "prnap;": '\U00002AB9',
+ "prnsim;": '\U000022E8',
+ "prod;": '\U0000220F',
+ "profalar;": '\U0000232E',
+ "profline;": '\U00002312',
+ "profsurf;": '\U00002313',
+ "prop;": '\U0000221D',
+ "propto;": '\U0000221D',
+ "prsim;": '\U0000227E',
+ "prurel;": '\U000022B0',
+ "pscr;": '\U0001D4C5',
+ "psi;": '\U000003C8',
+ "puncsp;": '\U00002008',
+ "qfr;": '\U0001D52E',
+ "qint;": '\U00002A0C',
+ "qopf;": '\U0001D562',
+ "qprime;": '\U00002057',
+ "qscr;": '\U0001D4C6',
+ "quaternions;": '\U0000210D',
+ "quatint;": '\U00002A16',
+ "quest;": '\U0000003F',
+ "questeq;": '\U0000225F',
+ "quot;": '\U00000022',
+ "rAarr;": '\U000021DB',
+ "rArr;": '\U000021D2',
+ "rAtail;": '\U0000291C',
+ "rBarr;": '\U0000290F',
+ "rHar;": '\U00002964',
+ "racute;": '\U00000155',
+ "radic;": '\U0000221A',
+ "raemptyv;": '\U000029B3',
+ "rang;": '\U000027E9',
+ "rangd;": '\U00002992',
+ "range;": '\U000029A5',
+ "rangle;": '\U000027E9',
+ "raquo;": '\U000000BB',
+ "rarr;": '\U00002192',
+ "rarrap;": '\U00002975',
+ "rarrb;": '\U000021E5',
+ "rarrbfs;": '\U00002920',
+ "rarrc;": '\U00002933',
+ "rarrfs;": '\U0000291E',
+ "rarrhk;": '\U000021AA',
+ "rarrlp;": '\U000021AC',
+ "rarrpl;": '\U00002945',
+ "rarrsim;": '\U00002974',
+ "rarrtl;": '\U000021A3',
+ "rarrw;": '\U0000219D',
+ "ratail;": '\U0000291A',
+ "ratio;": '\U00002236',
+ "rationals;": '\U0000211A',
+ "rbarr;": '\U0000290D',
+ "rbbrk;": '\U00002773',
+ "rbrace;": '\U0000007D',
+ "rbrack;": '\U0000005D',
+ "rbrke;": '\U0000298C',
+ "rbrksld;": '\U0000298E',
+ "rbrkslu;": '\U00002990',
+ "rcaron;": '\U00000159',
+ "rcedil;": '\U00000157',
+ "rceil;": '\U00002309',
+ "rcub;": '\U0000007D',
+ "rcy;": '\U00000440',
+ "rdca;": '\U00002937',
+ "rdldhar;": '\U00002969',
+ "rdquo;": '\U0000201D',
+ "rdquor;": '\U0000201D',
+ "rdsh;": '\U000021B3',
+ "real;": '\U0000211C',
+ "realine;": '\U0000211B',
+ "realpart;": '\U0000211C',
+ "reals;": '\U0000211D',
+ "rect;": '\U000025AD',
+ "reg;": '\U000000AE',
+ "rfisht;": '\U0000297D',
+ "rfloor;": '\U0000230B',
+ "rfr;": '\U0001D52F',
+ "rhard;": '\U000021C1',
+ "rharu;": '\U000021C0',
+ "rharul;": '\U0000296C',
+ "rho;": '\U000003C1',
+ "rhov;": '\U000003F1',
+ "rightarrow;": '\U00002192',
+ "rightarrowtail;": '\U000021A3',
+ "rightharpoondown;": '\U000021C1',
+ "rightharpoonup;": '\U000021C0',
+ "rightleftarrows;": '\U000021C4',
+ "rightleftharpoons;": '\U000021CC',
+ "rightrightarrows;": '\U000021C9',
+ "rightsquigarrow;": '\U0000219D',
+ "rightthreetimes;": '\U000022CC',
+ "ring;": '\U000002DA',
+ "risingdotseq;": '\U00002253',
+ "rlarr;": '\U000021C4',
+ "rlhar;": '\U000021CC',
+ "rlm;": '\U0000200F',
+ "rmoust;": '\U000023B1',
+ "rmoustache;": '\U000023B1',
+ "rnmid;": '\U00002AEE',
+ "roang;": '\U000027ED',
+ "roarr;": '\U000021FE',
+ "robrk;": '\U000027E7',
+ "ropar;": '\U00002986',
+ "ropf;": '\U0001D563',
+ "roplus;": '\U00002A2E',
+ "rotimes;": '\U00002A35',
+ "rpar;": '\U00000029',
+ "rpargt;": '\U00002994',
+ "rppolint;": '\U00002A12',
+ "rrarr;": '\U000021C9',
+ "rsaquo;": '\U0000203A',
+ "rscr;": '\U0001D4C7',
+ "rsh;": '\U000021B1',
+ "rsqb;": '\U0000005D',
+ "rsquo;": '\U00002019',
+ "rsquor;": '\U00002019',
+ "rthree;": '\U000022CC',
+ "rtimes;": '\U000022CA',
+ "rtri;": '\U000025B9',
+ "rtrie;": '\U000022B5',
+ "rtrif;": '\U000025B8',
+ "rtriltri;": '\U000029CE',
+ "ruluhar;": '\U00002968',
+ "rx;": '\U0000211E',
+ "sacute;": '\U0000015B',
+ "sbquo;": '\U0000201A',
+ "sc;": '\U0000227B',
+ "scE;": '\U00002AB4',
+ "scap;": '\U00002AB8',
+ "scaron;": '\U00000161',
+ "sccue;": '\U0000227D',
+ "sce;": '\U00002AB0',
+ "scedil;": '\U0000015F',
+ "scirc;": '\U0000015D',
+ "scnE;": '\U00002AB6',
+ "scnap;": '\U00002ABA',
+ "scnsim;": '\U000022E9',
+ "scpolint;": '\U00002A13',
+ "scsim;": '\U0000227F',
+ "scy;": '\U00000441',
+ "sdot;": '\U000022C5',
+ "sdotb;": '\U000022A1',
+ "sdote;": '\U00002A66',
+ "seArr;": '\U000021D8',
+ "searhk;": '\U00002925',
+ "searr;": '\U00002198',
+ "searrow;": '\U00002198',
+ "sect;": '\U000000A7',
+ "semi;": '\U0000003B',
+ "seswar;": '\U00002929',
+ "setminus;": '\U00002216',
+ "setmn;": '\U00002216',
+ "sext;": '\U00002736',
+ "sfr;": '\U0001D530',
+ "sfrown;": '\U00002322',
+ "sharp;": '\U0000266F',
+ "shchcy;": '\U00000449',
+ "shcy;": '\U00000448',
+ "shortmid;": '\U00002223',
+ "shortparallel;": '\U00002225',
+ "shy;": '\U000000AD',
+ "sigma;": '\U000003C3',
+ "sigmaf;": '\U000003C2',
+ "sigmav;": '\U000003C2',
+ "sim;": '\U0000223C',
+ "simdot;": '\U00002A6A',
+ "sime;": '\U00002243',
+ "simeq;": '\U00002243',
+ "simg;": '\U00002A9E',
+ "simgE;": '\U00002AA0',
+ "siml;": '\U00002A9D',
+ "simlE;": '\U00002A9F',
+ "simne;": '\U00002246',
+ "simplus;": '\U00002A24',
+ "simrarr;": '\U00002972',
+ "slarr;": '\U00002190',
+ "smallsetminus;": '\U00002216',
+ "smashp;": '\U00002A33',
+ "smeparsl;": '\U000029E4',
+ "smid;": '\U00002223',
+ "smile;": '\U00002323',
+ "smt;": '\U00002AAA',
+ "smte;": '\U00002AAC',
+ "softcy;": '\U0000044C',
+ "sol;": '\U0000002F',
+ "solb;": '\U000029C4',
+ "solbar;": '\U0000233F',
+ "sopf;": '\U0001D564',
+ "spades;": '\U00002660',
+ "spadesuit;": '\U00002660',
+ "spar;": '\U00002225',
+ "sqcap;": '\U00002293',
+ "sqcup;": '\U00002294',
+ "sqsub;": '\U0000228F',
+ "sqsube;": '\U00002291',
+ "sqsubset;": '\U0000228F',
+ "sqsubseteq;": '\U00002291',
+ "sqsup;": '\U00002290',
+ "sqsupe;": '\U00002292',
+ "sqsupset;": '\U00002290',
+ "sqsupseteq;": '\U00002292',
+ "squ;": '\U000025A1',
+ "square;": '\U000025A1',
+ "squarf;": '\U000025AA',
+ "squf;": '\U000025AA',
+ "srarr;": '\U00002192',
+ "sscr;": '\U0001D4C8',
+ "ssetmn;": '\U00002216',
+ "ssmile;": '\U00002323',
+ "sstarf;": '\U000022C6',
+ "star;": '\U00002606',
+ "starf;": '\U00002605',
+ "straightepsilon;": '\U000003F5',
+ "straightphi;": '\U000003D5',
+ "strns;": '\U000000AF',
+ "sub;": '\U00002282',
+ "subE;": '\U00002AC5',
+ "subdot;": '\U00002ABD',
+ "sube;": '\U00002286',
+ "subedot;": '\U00002AC3',
+ "submult;": '\U00002AC1',
+ "subnE;": '\U00002ACB',
+ "subne;": '\U0000228A',
+ "subplus;": '\U00002ABF',
+ "subrarr;": '\U00002979',
+ "subset;": '\U00002282',
+ "subseteq;": '\U00002286',
+ "subseteqq;": '\U00002AC5',
+ "subsetneq;": '\U0000228A',
+ "subsetneqq;": '\U00002ACB',
+ "subsim;": '\U00002AC7',
+ "subsub;": '\U00002AD5',
+ "subsup;": '\U00002AD3',
+ "succ;": '\U0000227B',
+ "succapprox;": '\U00002AB8',
+ "succcurlyeq;": '\U0000227D',
+ "succeq;": '\U00002AB0',
+ "succnapprox;": '\U00002ABA',
+ "succneqq;": '\U00002AB6',
+ "succnsim;": '\U000022E9',
+ "succsim;": '\U0000227F',
+ "sum;": '\U00002211',
+ "sung;": '\U0000266A',
+ "sup;": '\U00002283',
+ "sup1;": '\U000000B9',
+ "sup2;": '\U000000B2',
+ "sup3;": '\U000000B3',
+ "supE;": '\U00002AC6',
+ "supdot;": '\U00002ABE',
+ "supdsub;": '\U00002AD8',
+ "supe;": '\U00002287',
+ "supedot;": '\U00002AC4',
+ "suphsol;": '\U000027C9',
+ "suphsub;": '\U00002AD7',
+ "suplarr;": '\U0000297B',
+ "supmult;": '\U00002AC2',
+ "supnE;": '\U00002ACC',
+ "supne;": '\U0000228B',
+ "supplus;": '\U00002AC0',
+ "supset;": '\U00002283',
+ "supseteq;": '\U00002287',
+ "supseteqq;": '\U00002AC6',
+ "supsetneq;": '\U0000228B',
+ "supsetneqq;": '\U00002ACC',
+ "supsim;": '\U00002AC8',
+ "supsub;": '\U00002AD4',
+ "supsup;": '\U00002AD6',
+ "swArr;": '\U000021D9',
+ "swarhk;": '\U00002926',
+ "swarr;": '\U00002199',
+ "swarrow;": '\U00002199',
+ "swnwar;": '\U0000292A',
+ "szlig;": '\U000000DF',
+ "target;": '\U00002316',
+ "tau;": '\U000003C4',
+ "tbrk;": '\U000023B4',
+ "tcaron;": '\U00000165',
+ "tcedil;": '\U00000163',
+ "tcy;": '\U00000442',
+ "tdot;": '\U000020DB',
+ "telrec;": '\U00002315',
+ "tfr;": '\U0001D531',
+ "there4;": '\U00002234',
+ "therefore;": '\U00002234',
+ "theta;": '\U000003B8',
+ "thetasym;": '\U000003D1',
+ "thetav;": '\U000003D1',
+ "thickapprox;": '\U00002248',
+ "thicksim;": '\U0000223C',
+ "thinsp;": '\U00002009',
+ "thkap;": '\U00002248',
+ "thksim;": '\U0000223C',
+ "thorn;": '\U000000FE',
+ "tilde;": '\U000002DC',
+ "times;": '\U000000D7',
+ "timesb;": '\U000022A0',
+ "timesbar;": '\U00002A31',
+ "timesd;": '\U00002A30',
+ "tint;": '\U0000222D',
+ "toea;": '\U00002928',
+ "top;": '\U000022A4',
+ "topbot;": '\U00002336',
+ "topcir;": '\U00002AF1',
+ "topf;": '\U0001D565',
+ "topfork;": '\U00002ADA',
+ "tosa;": '\U00002929',
+ "tprime;": '\U00002034',
+ "trade;": '\U00002122',
+ "triangle;": '\U000025B5',
+ "triangledown;": '\U000025BF',
+ "triangleleft;": '\U000025C3',
+ "trianglelefteq;": '\U000022B4',
+ "triangleq;": '\U0000225C',
+ "triangleright;": '\U000025B9',
+ "trianglerighteq;": '\U000022B5',
+ "tridot;": '\U000025EC',
+ "trie;": '\U0000225C',
+ "triminus;": '\U00002A3A',
+ "triplus;": '\U00002A39',
+ "trisb;": '\U000029CD',
+ "tritime;": '\U00002A3B',
+ "trpezium;": '\U000023E2',
+ "tscr;": '\U0001D4C9',
+ "tscy;": '\U00000446',
+ "tshcy;": '\U0000045B',
+ "tstrok;": '\U00000167',
+ "twixt;": '\U0000226C',
+ "twoheadleftarrow;": '\U0000219E',
+ "twoheadrightarrow;": '\U000021A0',
+ "uArr;": '\U000021D1',
+ "uHar;": '\U00002963',
+ "uacute;": '\U000000FA',
+ "uarr;": '\U00002191',
+ "ubrcy;": '\U0000045E',
+ "ubreve;": '\U0000016D',
+ "ucirc;": '\U000000FB',
+ "ucy;": '\U00000443',
+ "udarr;": '\U000021C5',
+ "udblac;": '\U00000171',
+ "udhar;": '\U0000296E',
+ "ufisht;": '\U0000297E',
+ "ufr;": '\U0001D532',
+ "ugrave;": '\U000000F9',
+ "uharl;": '\U000021BF',
+ "uharr;": '\U000021BE',
+ "uhblk;": '\U00002580',
+ "ulcorn;": '\U0000231C',
+ "ulcorner;": '\U0000231C',
+ "ulcrop;": '\U0000230F',
+ "ultri;": '\U000025F8',
+ "umacr;": '\U0000016B',
+ "uml;": '\U000000A8',
+ "uogon;": '\U00000173',
+ "uopf;": '\U0001D566',
+ "uparrow;": '\U00002191',
+ "updownarrow;": '\U00002195',
+ "upharpoonleft;": '\U000021BF',
+ "upharpoonright;": '\U000021BE',
+ "uplus;": '\U0000228E',
+ "upsi;": '\U000003C5',
+ "upsih;": '\U000003D2',
+ "upsilon;": '\U000003C5',
+ "upuparrows;": '\U000021C8',
+ "urcorn;": '\U0000231D',
+ "urcorner;": '\U0000231D',
+ "urcrop;": '\U0000230E',
+ "uring;": '\U0000016F',
+ "urtri;": '\U000025F9',
+ "uscr;": '\U0001D4CA',
+ "utdot;": '\U000022F0',
+ "utilde;": '\U00000169',
+ "utri;": '\U000025B5',
+ "utrif;": '\U000025B4',
+ "uuarr;": '\U000021C8',
+ "uuml;": '\U000000FC',
+ "uwangle;": '\U000029A7',
+ "vArr;": '\U000021D5',
+ "vBar;": '\U00002AE8',
+ "vBarv;": '\U00002AE9',
+ "vDash;": '\U000022A8',
+ "vangrt;": '\U0000299C',
+ "varepsilon;": '\U000003F5',
+ "varkappa;": '\U000003F0',
+ "varnothing;": '\U00002205',
+ "varphi;": '\U000003D5',
+ "varpi;": '\U000003D6',
+ "varpropto;": '\U0000221D',
+ "varr;": '\U00002195',
+ "varrho;": '\U000003F1',
+ "varsigma;": '\U000003C2',
+ "vartheta;": '\U000003D1',
+ "vartriangleleft;": '\U000022B2',
+ "vartriangleright;": '\U000022B3',
+ "vcy;": '\U00000432',
+ "vdash;": '\U000022A2',
+ "vee;": '\U00002228',
+ "veebar;": '\U000022BB',
+ "veeeq;": '\U0000225A',
+ "vellip;": '\U000022EE',
+ "verbar;": '\U0000007C',
+ "vert;": '\U0000007C',
+ "vfr;": '\U0001D533',
+ "vltri;": '\U000022B2',
+ "vopf;": '\U0001D567',
+ "vprop;": '\U0000221D',
+ "vrtri;": '\U000022B3',
+ "vscr;": '\U0001D4CB',
+ "vzigzag;": '\U0000299A',
+ "wcirc;": '\U00000175',
+ "wedbar;": '\U00002A5F',
+ "wedge;": '\U00002227',
+ "wedgeq;": '\U00002259',
+ "weierp;": '\U00002118',
+ "wfr;": '\U0001D534',
+ "wopf;": '\U0001D568',
+ "wp;": '\U00002118',
+ "wr;": '\U00002240',
+ "wreath;": '\U00002240',
+ "wscr;": '\U0001D4CC',
+ "xcap;": '\U000022C2',
+ "xcirc;": '\U000025EF',
+ "xcup;": '\U000022C3',
+ "xdtri;": '\U000025BD',
+ "xfr;": '\U0001D535',
+ "xhArr;": '\U000027FA',
+ "xharr;": '\U000027F7',
+ "xi;": '\U000003BE',
+ "xlArr;": '\U000027F8',
+ "xlarr;": '\U000027F5',
+ "xmap;": '\U000027FC',
+ "xnis;": '\U000022FB',
+ "xodot;": '\U00002A00',
+ "xopf;": '\U0001D569',
+ "xoplus;": '\U00002A01',
+ "xotime;": '\U00002A02',
+ "xrArr;": '\U000027F9',
+ "xrarr;": '\U000027F6',
+ "xscr;": '\U0001D4CD',
+ "xsqcup;": '\U00002A06',
+ "xuplus;": '\U00002A04',
+ "xutri;": '\U000025B3',
+ "xvee;": '\U000022C1',
+ "xwedge;": '\U000022C0',
+ "yacute;": '\U000000FD',
+ "yacy;": '\U0000044F',
+ "ycirc;": '\U00000177',
+ "ycy;": '\U0000044B',
+ "yen;": '\U000000A5',
+ "yfr;": '\U0001D536',
+ "yicy;": '\U00000457',
+ "yopf;": '\U0001D56A',
+ "yscr;": '\U0001D4CE',
+ "yucy;": '\U0000044E',
+ "yuml;": '\U000000FF',
+ "zacute;": '\U0000017A',
+ "zcaron;": '\U0000017E',
+ "zcy;": '\U00000437',
+ "zdot;": '\U0000017C',
+ "zeetrf;": '\U00002128',
+ "zeta;": '\U000003B6',
+ "zfr;": '\U0001D537',
+ "zhcy;": '\U00000436',
+ "zigrarr;": '\U000021DD',
+ "zopf;": '\U0001D56B',
+ "zscr;": '\U0001D4CF',
+ "zwj;": '\U0000200D',
+ "zwnj;": '\U0000200C',
+ "AElig": '\U000000C6',
+ "AMP": '\U00000026',
+ "Aacute": '\U000000C1',
+ "Acirc": '\U000000C2',
+ "Agrave": '\U000000C0',
+ "Aring": '\U000000C5',
+ "Atilde": '\U000000C3',
+ "Auml": '\U000000C4',
+ "COPY": '\U000000A9',
+ "Ccedil": '\U000000C7',
+ "ETH": '\U000000D0',
+ "Eacute": '\U000000C9',
+ "Ecirc": '\U000000CA',
+ "Egrave": '\U000000C8',
+ "Euml": '\U000000CB',
+ "GT": '\U0000003E',
+ "Iacute": '\U000000CD',
+ "Icirc": '\U000000CE',
+ "Igrave": '\U000000CC',
+ "Iuml": '\U000000CF',
+ "LT": '\U0000003C',
+ "Ntilde": '\U000000D1',
+ "Oacute": '\U000000D3',
+ "Ocirc": '\U000000D4',
+ "Ograve": '\U000000D2',
+ "Oslash": '\U000000D8',
+ "Otilde": '\U000000D5',
+ "Ouml": '\U000000D6',
+ "QUOT": '\U00000022',
+ "REG": '\U000000AE',
+ "THORN": '\U000000DE',
+ "Uacute": '\U000000DA',
+ "Ucirc": '\U000000DB',
+ "Ugrave": '\U000000D9',
+ "Uuml": '\U000000DC',
+ "Yacute": '\U000000DD',
+ "aacute": '\U000000E1',
+ "acirc": '\U000000E2',
+ "acute": '\U000000B4',
+ "aelig": '\U000000E6',
+ "agrave": '\U000000E0',
+ "amp": '\U00000026',
+ "aring": '\U000000E5',
+ "atilde": '\U000000E3',
+ "auml": '\U000000E4',
+ "brvbar": '\U000000A6',
+ "ccedil": '\U000000E7',
+ "cedil": '\U000000B8',
+ "cent": '\U000000A2',
+ "copy": '\U000000A9',
+ "curren": '\U000000A4',
+ "deg": '\U000000B0',
+ "divide": '\U000000F7',
+ "eacute": '\U000000E9',
+ "ecirc": '\U000000EA',
+ "egrave": '\U000000E8',
+ "eth": '\U000000F0',
+ "euml": '\U000000EB',
+ "frac12": '\U000000BD',
+ "frac14": '\U000000BC',
+ "frac34": '\U000000BE',
+ "gt": '\U0000003E',
+ "iacute": '\U000000ED',
+ "icirc": '\U000000EE',
+ "iexcl": '\U000000A1',
+ "igrave": '\U000000EC',
+ "iquest": '\U000000BF',
+ "iuml": '\U000000EF',
+ "laquo": '\U000000AB',
+ "lt": '\U0000003C',
+ "macr": '\U000000AF',
+ "micro": '\U000000B5',
+ "middot": '\U000000B7',
+ "nbsp": '\U000000A0',
+ "not": '\U000000AC',
+ "ntilde": '\U000000F1',
+ "oacute": '\U000000F3',
+ "ocirc": '\U000000F4',
+ "ograve": '\U000000F2',
+ "ordf": '\U000000AA',
+ "ordm": '\U000000BA',
+ "oslash": '\U000000F8',
+ "otilde": '\U000000F5',
+ "ouml": '\U000000F6',
+ "para": '\U000000B6',
+ "plusmn": '\U000000B1',
+ "pound": '\U000000A3',
+ "quot": '\U00000022',
+ "raquo": '\U000000BB',
+ "reg": '\U000000AE',
+ "sect": '\U000000A7',
+ "shy": '\U000000AD',
+ "sup1": '\U000000B9',
+ "sup2": '\U000000B2',
+ "sup3": '\U000000B3',
+ "szlig": '\U000000DF',
+ "thorn": '\U000000FE',
+ "times": '\U000000D7',
+ "uacute": '\U000000FA',
+ "ucirc": '\U000000FB',
+ "ugrave": '\U000000F9',
+ "uml": '\U000000A8',
+ "uuml": '\U000000FC',
+ "yacute": '\U000000FD',
+ "yen": '\U000000A5',
+ "yuml": '\U000000FF',
+ }
+
+ entity2 = map[string][2]rune{
+ // TODO(nigeltao): Handle replacements that are wider than their names.
+ // "nLt;": {'\u226A', '\u20D2'},
+ // "nGt;": {'\u226B', '\u20D2'},
+ "NotEqualTilde;": {'\u2242', '\u0338'},
+ "NotGreaterFullEqual;": {'\u2267', '\u0338'},
+ "NotGreaterGreater;": {'\u226B', '\u0338'},
+ "NotGreaterSlantEqual;": {'\u2A7E', '\u0338'},
+ "NotHumpDownHump;": {'\u224E', '\u0338'},
+ "NotHumpEqual;": {'\u224F', '\u0338'},
+ "NotLeftTriangleBar;": {'\u29CF', '\u0338'},
+ "NotLessLess;": {'\u226A', '\u0338'},
+ "NotLessSlantEqual;": {'\u2A7D', '\u0338'},
+ "NotNestedGreaterGreater;": {'\u2AA2', '\u0338'},
+ "NotNestedLessLess;": {'\u2AA1', '\u0338'},
+ "NotPrecedesEqual;": {'\u2AAF', '\u0338'},
+ "NotRightTriangleBar;": {'\u29D0', '\u0338'},
+ "NotSquareSubset;": {'\u228F', '\u0338'},
+ "NotSquareSuperset;": {'\u2290', '\u0338'},
+ "NotSubset;": {'\u2282', '\u20D2'},
+ "NotSucceedsEqual;": {'\u2AB0', '\u0338'},
+ "NotSucceedsTilde;": {'\u227F', '\u0338'},
+ "NotSuperset;": {'\u2283', '\u20D2'},
+ "ThickSpace;": {'\u205F', '\u200A'},
+ "acE;": {'\u223E', '\u0333'},
+ "bne;": {'\u003D', '\u20E5'},
+ "bnequiv;": {'\u2261', '\u20E5'},
+ "caps;": {'\u2229', '\uFE00'},
+ "cups;": {'\u222A', '\uFE00'},
+ "fjlig;": {'\u0066', '\u006A'},
+ "gesl;": {'\u22DB', '\uFE00'},
+ "gvertneqq;": {'\u2269', '\uFE00'},
+ "gvnE;": {'\u2269', '\uFE00'},
+ "lates;": {'\u2AAD', '\uFE00'},
+ "lesg;": {'\u22DA', '\uFE00'},
+ "lvertneqq;": {'\u2268', '\uFE00'},
+ "lvnE;": {'\u2268', '\uFE00'},
+ "nGg;": {'\u22D9', '\u0338'},
+ "nGtv;": {'\u226B', '\u0338'},
+ "nLl;": {'\u22D8', '\u0338'},
+ "nLtv;": {'\u226A', '\u0338'},
+ "nang;": {'\u2220', '\u20D2'},
+ "napE;": {'\u2A70', '\u0338'},
+ "napid;": {'\u224B', '\u0338'},
+ "nbump;": {'\u224E', '\u0338'},
+ "nbumpe;": {'\u224F', '\u0338'},
+ "ncongdot;": {'\u2A6D', '\u0338'},
+ "nedot;": {'\u2250', '\u0338'},
+ "nesim;": {'\u2242', '\u0338'},
+ "ngE;": {'\u2267', '\u0338'},
+ "ngeqq;": {'\u2267', '\u0338'},
+ "ngeqslant;": {'\u2A7E', '\u0338'},
+ "nges;": {'\u2A7E', '\u0338'},
+ "nlE;": {'\u2266', '\u0338'},
+ "nleqq;": {'\u2266', '\u0338'},
+ "nleqslant;": {'\u2A7D', '\u0338'},
+ "nles;": {'\u2A7D', '\u0338'},
+ "notinE;": {'\u22F9', '\u0338'},
+ "notindot;": {'\u22F5', '\u0338'},
+ "nparsl;": {'\u2AFD', '\u20E5'},
+ "npart;": {'\u2202', '\u0338'},
+ "npre;": {'\u2AAF', '\u0338'},
+ "npreceq;": {'\u2AAF', '\u0338'},
+ "nrarrc;": {'\u2933', '\u0338'},
+ "nrarrw;": {'\u219D', '\u0338'},
+ "nsce;": {'\u2AB0', '\u0338'},
+ "nsubE;": {'\u2AC5', '\u0338'},
+ "nsubset;": {'\u2282', '\u20D2'},
+ "nsubseteqq;": {'\u2AC5', '\u0338'},
+ "nsucceq;": {'\u2AB0', '\u0338'},
+ "nsupE;": {'\u2AC6', '\u0338'},
+ "nsupset;": {'\u2283', '\u20D2'},
+ "nsupseteqq;": {'\u2AC6', '\u0338'},
+ "nvap;": {'\u224D', '\u20D2'},
+ "nvge;": {'\u2265', '\u20D2'},
+ "nvgt;": {'\u003E', '\u20D2'},
+ "nvle;": {'\u2264', '\u20D2'},
+ "nvlt;": {'\u003C', '\u20D2'},
+ "nvltrie;": {'\u22B4', '\u20D2'},
+ "nvrtrie;": {'\u22B5', '\u20D2'},
+ "nvsim;": {'\u223C', '\u20D2'},
+ "race;": {'\u223D', '\u0331'},
+ "smtes;": {'\u2AAC', '\uFE00'},
+ "sqcaps;": {'\u2293', '\uFE00'},
+ "sqcups;": {'\u2294', '\uFE00'},
+ "varsubsetneq;": {'\u228A', '\uFE00'},
+ "varsubsetneqq;": {'\u2ACB', '\uFE00'},
+ "varsupsetneq;": {'\u228B', '\uFE00'},
+ "varsupsetneqq;": {'\u2ACC', '\uFE00'},
+ "vnsub;": {'\u2282', '\u20D2'},
+ "vnsup;": {'\u2283', '\u20D2'},
+ "vsubnE;": {'\u2ACB', '\uFE00'},
+ "vsubne;": {'\u228A', '\uFE00'},
+ "vsupnE;": {'\u2ACC', '\uFE00'},
+ "vsupne;": {'\u228B', '\uFE00'},
+ }
+
+ return entity, entity2
+})
diff --git a/go/src/html/entity_test.go b/go/src/html/entity_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..4011da6141db4bc9fc82021b6a7ba59001ab0c78
--- /dev/null
+++ b/go/src/html/entity_test.go
@@ -0,0 +1,35 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package html
+
+import (
+ "testing"
+ "unicode/utf8"
+)
+
+func TestEntityLength(t *testing.T) {
+ entity, entity2 := entityMaps()
+
+ if len(entity) == 0 || len(entity2) == 0 {
+ t.Fatal("maps not loaded")
+ }
+
+ // We verify that the length of UTF-8 encoding of each value is <= 1 + len(key).
+ // The +1 comes from the leading "&". This property implies that the length of
+ // unescaped text is <= the length of escaped text.
+ for k, v := range entity {
+ if 1+len(k) < utf8.RuneLen(v) {
+ t.Error("escaped entity &" + k + " is shorter than its UTF-8 encoding " + string(v))
+ }
+ if len(k) > longestEntityWithoutSemicolon && k[len(k)-1] != ';' {
+ t.Errorf("entity name %s is %d characters, but longestEntityWithoutSemicolon=%d", k, len(k), longestEntityWithoutSemicolon)
+ }
+ }
+ for k, v := range entity2 {
+ if 1+len(k) < utf8.RuneLen(v[0])+utf8.RuneLen(v[1]) {
+ t.Error("escaped entity &" + k + " is shorter than its UTF-8 encoding " + string(v[0]) + string(v[1]))
+ }
+ }
+}
diff --git a/go/src/html/escape.go b/go/src/html/escape.go
new file mode 100644
index 0000000000000000000000000000000000000000..d66a3e48378faa4beba20ed388d22afc1f605cfa
--- /dev/null
+++ b/go/src/html/escape.go
@@ -0,0 +1,214 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package html provides functions for escaping and unescaping HTML text.
+package html
+
+import (
+ "strings"
+ "unicode/utf8"
+)
+
+// These replacements permit compatibility with old numeric entities that
+// assumed Windows-1252 encoding.
+// https://html.spec.whatwg.org/multipage/parsing.html#numeric-character-reference-end-state
+var replacementTable = [...]rune{
+ '\u20AC', // First entry is what 0x80 should be replaced with.
+ '\u0081',
+ '\u201A',
+ '\u0192',
+ '\u201E',
+ '\u2026',
+ '\u2020',
+ '\u2021',
+ '\u02C6',
+ '\u2030',
+ '\u0160',
+ '\u2039',
+ '\u0152',
+ '\u008D',
+ '\u017D',
+ '\u008F',
+ '\u0090',
+ '\u2018',
+ '\u2019',
+ '\u201C',
+ '\u201D',
+ '\u2022',
+ '\u2013',
+ '\u2014',
+ '\u02DC',
+ '\u2122',
+ '\u0161',
+ '\u203A',
+ '\u0153',
+ '\u009D',
+ '\u017E',
+ '\u0178', // Last entry is 0x9F.
+ // 0x00->'\uFFFD' is handled programmatically.
+ // 0x0D->'\u000D' is a no-op.
+}
+
+// unescapeEntity reads an entity like "<" from b[src:] and writes the
+// corresponding "<" to b[dst:], returning the incremented dst and src cursors.
+// Precondition: b[src] == '&' && dst <= src.
+func unescapeEntity(b []byte, dst, src int, entity map[string]rune, entity2 map[string][2]rune) (dst1, src1 int) {
+ const attribute = false
+
+ // http://www.whatwg.org/specs/web-apps/current-work/multipage/tokenization.html#consume-a-character-reference
+
+ // i starts at 1 because we already know that s[0] == '&'.
+ i, s := 1, b[src:]
+
+ if len(s) <= 1 {
+ b[dst] = b[src]
+ return dst + 1, src + 1
+ }
+
+ if s[i] == '#' {
+ if len(s) <= 3 { // We need to have at least ".".
+ b[dst] = b[src]
+ return dst + 1, src + 1
+ }
+ i++
+ c := s[i]
+ hex := false
+ if c == 'x' || c == 'X' {
+ hex = true
+ i++
+ }
+
+ x := '\x00'
+ for i < len(s) {
+ c = s[i]
+ i++
+ if hex {
+ if '0' <= c && c <= '9' {
+ x = 16*x + rune(c) - '0'
+ continue
+ } else if 'a' <= c && c <= 'f' {
+ x = 16*x + rune(c) - 'a' + 10
+ continue
+ } else if 'A' <= c && c <= 'F' {
+ x = 16*x + rune(c) - 'A' + 10
+ continue
+ }
+ } else if '0' <= c && c <= '9' {
+ x = 10*x + rune(c) - '0'
+ continue
+ }
+ if c != ';' {
+ i--
+ }
+ break
+ }
+
+ if i <= 3 { // No characters matched.
+ b[dst] = b[src]
+ return dst + 1, src + 1
+ }
+
+ if 0x80 <= x && x <= 0x9F {
+ // Replace characters from Windows-1252 with UTF-8 equivalents.
+ x = replacementTable[x-0x80]
+ } else if x == 0 || (0xD800 <= x && x <= 0xDFFF) || x > 0x10FFFF {
+ // Replace invalid characters with the replacement character.
+ x = '\uFFFD'
+ }
+
+ return dst + utf8.EncodeRune(b[dst:], x), src + i
+ }
+
+ // Consume the maximum number of characters possible, with the
+ // consumed characters matching one of the named references.
+
+ for i < len(s) {
+ c := s[i]
+ i++
+ // Lower-cased characters are more common in entities, so we check for them first.
+ if 'a' <= c && c <= 'z' || 'A' <= c && c <= 'Z' || '0' <= c && c <= '9' {
+ continue
+ }
+ if c != ';' {
+ i--
+ }
+ break
+ }
+
+ entityName := s[1:i]
+ if len(entityName) == 0 {
+ // No-op.
+ } else if attribute && entityName[len(entityName)-1] != ';' && len(s) > i && s[i] == '=' {
+ // No-op.
+ } else if x := entity[string(entityName)]; x != 0 {
+ return dst + utf8.EncodeRune(b[dst:], x), src + i
+ } else if x := entity2[string(entityName)]; x[0] != 0 {
+ dst1 := dst + utf8.EncodeRune(b[dst:], x[0])
+ return dst1 + utf8.EncodeRune(b[dst1:], x[1]), src + i
+ } else if !attribute {
+ maxLen := len(entityName) - 1
+ if maxLen > longestEntityWithoutSemicolon {
+ maxLen = longestEntityWithoutSemicolon
+ }
+ for j := maxLen; j > 1; j-- {
+ if x := entity[string(entityName[:j])]; x != 0 {
+ return dst + utf8.EncodeRune(b[dst:], x), src + j + 1
+ }
+ }
+ }
+
+ dst1, src1 = dst+i, src+i
+ copy(b[dst:dst1], b[src:src1])
+ return dst1, src1
+}
+
+var htmlEscaper = strings.NewReplacer(
+ `&`, "&",
+ `'`, "'", // "'" is shorter than "'" and apos was not in HTML until HTML5.
+ `<`, "<",
+ `>`, ">",
+ `"`, """, // """ is shorter than """.
+)
+
+// EscapeString escapes special characters like "<" to become "<". It
+// escapes only five such characters: <, >, &, ' and ".
+// [UnescapeString](EscapeString(s)) == s always holds, but the converse isn't
+// always true.
+func EscapeString(s string) string {
+ return htmlEscaper.Replace(s)
+}
+
+// UnescapeString unescapes entities like "<" to become "<". It unescapes a
+// larger range of entities than [EscapeString] escapes. For example, "á"
+// unescapes to "á", as does "á" and "á".
+// UnescapeString([EscapeString](s)) == s always holds, but the converse isn't
+// always true.
+func UnescapeString(s string) string {
+ i := strings.IndexByte(s, '&')
+
+ if i < 0 {
+ return s
+ }
+
+ b := []byte(s)
+ entity, entity2 := entityMaps()
+ dst, src := unescapeEntity(b, i, i, entity, entity2)
+ for len(s[src:]) > 0 {
+ if s[src] == '&' {
+ i = 0
+ } else {
+ i = strings.IndexByte(s[src:], '&')
+ }
+ if i < 0 {
+ dst += copy(b[dst:], s[src:])
+ break
+ }
+
+ if i > 0 {
+ copy(b[dst:], s[src:src+i])
+ }
+ dst, src = unescapeEntity(b, dst+i, src+i, entity, entity2)
+ }
+ return string(b[:dst])
+}
diff --git a/go/src/html/escape_test.go b/go/src/html/escape_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..8b51a55409fa55ee04149b31bafbe4657312d138
--- /dev/null
+++ b/go/src/html/escape_test.go
@@ -0,0 +1,169 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package html
+
+import (
+ "strings"
+ "testing"
+)
+
+type unescapeTest struct {
+ // A short description of the test case.
+ desc string
+ // The HTML text.
+ html string
+ // The unescaped text.
+ unescaped string
+}
+
+var unescapeTests = []unescapeTest{
+ // Handle no entities.
+ {
+ "copy",
+ "A\ttext\nstring",
+ "A\ttext\nstring",
+ },
+ // Handle simple named entities.
+ {
+ "simple",
+ "& > <",
+ "& > <",
+ },
+ // Handle hitting the end of the string.
+ {
+ "stringEnd",
+ "& &",
+ "& &",
+ },
+ // Handle entities with two codepoints.
+ {
+ "multiCodepoint",
+ "text ⋛︀ blah",
+ "text \u22db\ufe00 blah",
+ },
+ // Handle decimal numeric entities.
+ {
+ "decimalEntity",
+ "Delta = Δ ",
+ "Delta = Δ ",
+ },
+ // Handle hexadecimal numeric entities.
+ {
+ "hexadecimalEntity",
+ "Lambda = λ = λ ",
+ "Lambda = λ = λ ",
+ },
+ // Handle numeric early termination.
+ {
+ "numericEnds",
+ " 43 © = ©f = ©",
+ " €43 © = ©f = ©",
+ },
+ // Handle numeric ISO-8859-1 entity replacements.
+ {
+ "numericReplacements",
+ "Footnote",
+ "Footnote‡",
+ },
+ // Handle single ampersand.
+ {
+ "copySingleAmpersand",
+ "&",
+ "&",
+ },
+ // Handle ampersand followed by non-entity.
+ {
+ "copyAmpersandNonEntity",
+ "text &test",
+ "text &test",
+ },
+ // Handle "".
+ {
+ "copyAmpersandHash",
+ "text ",
+ "text ",
+ },
+}
+
+func TestUnescape(t *testing.T) {
+ for _, tt := range unescapeTests {
+ unescaped := UnescapeString(tt.html)
+ if unescaped != tt.unescaped {
+ t.Errorf("TestUnescape %s: want %q, got %q", tt.desc, tt.unescaped, unescaped)
+ }
+ }
+}
+
+func TestUnescapeEscape(t *testing.T) {
+ ss := []string{
+ ``,
+ `abc def`,
+ `a & b`,
+ `a&b`,
+ `a & b`,
+ `"`,
+ `"`,
+ `"<&>"`,
+ `"<&>"`,
+ `3&5==1 && 0<1, "0<1", a+acute=á`,
+ `The special characters are: <, >, &, ' and "`,
+ }
+ for _, s := range ss {
+ if got := UnescapeString(EscapeString(s)); got != s {
+ t.Errorf("got %q want %q", got, s)
+ }
+ }
+}
+
+var (
+ benchEscapeData = strings.Repeat("AAAAA < BBBBB > CCCCC & DDDDD ' EEEEE \" ", 100)
+ benchEscapeNone = strings.Repeat("AAAAA x BBBBB x CCCCC x DDDDD x EEEEE x ", 100)
+ benchUnescapeSparse = strings.Repeat(strings.Repeat("AAAAA x BBBBB x CCCCC x DDDDD x EEEEE x ", 10)+"&", 10)
+ benchUnescapeDense = strings.Repeat("&< & <", 100)
+)
+
+func BenchmarkEscape(b *testing.B) {
+ n := 0
+ for i := 0; i < b.N; i++ {
+ n += len(EscapeString(benchEscapeData))
+ }
+}
+
+func BenchmarkEscapeNone(b *testing.B) {
+ n := 0
+ for i := 0; i < b.N; i++ {
+ n += len(EscapeString(benchEscapeNone))
+ }
+}
+
+func BenchmarkUnescape(b *testing.B) {
+ s := EscapeString(benchEscapeData)
+ n := 0
+ for i := 0; i < b.N; i++ {
+ n += len(UnescapeString(s))
+ }
+}
+
+func BenchmarkUnescapeNone(b *testing.B) {
+ s := EscapeString(benchEscapeNone)
+ n := 0
+ for i := 0; i < b.N; i++ {
+ n += len(UnescapeString(s))
+ }
+}
+
+func BenchmarkUnescapeSparse(b *testing.B) {
+ n := 0
+ for i := 0; i < b.N; i++ {
+ n += len(UnescapeString(benchUnescapeSparse))
+ }
+}
+
+func BenchmarkUnescapeDense(b *testing.B) {
+ n := 0
+ for i := 0; i < b.N; i++ {
+ n += len(UnescapeString(benchUnescapeDense))
+ }
+}
diff --git a/go/src/html/example_test.go b/go/src/html/example_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..0e28cac1be5e4f8ead17ffb4b4cfd90803fc2e48
--- /dev/null
+++ b/go/src/html/example_test.go
@@ -0,0 +1,22 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package html_test
+
+import (
+ "fmt"
+ "html"
+)
+
+func ExampleEscapeString() {
+ const s = `"Fran & Freddie's Diner" `
+ fmt.Println(html.EscapeString(s))
+ // Output: "Fran & Freddie's Diner" <tasty@example.com>
+}
+
+func ExampleUnescapeString() {
+ const s = `"Fran & Freddie's Diner" <tasty@example.com>`
+ fmt.Println(html.UnescapeString(s))
+ // Output: "Fran & Freddie's Diner"
+}
diff --git a/go/src/html/fuzz_test.go b/go/src/html/fuzz_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..ed15d8f270b93e49ee852ba1b7bec901256b9076
--- /dev/null
+++ b/go/src/html/fuzz_test.go
@@ -0,0 +1,22 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package html
+
+import "testing"
+
+func FuzzEscapeUnescape(f *testing.F) {
+ f.Fuzz(func(t *testing.T, v string) {
+ e := EscapeString(v)
+ u := UnescapeString(e)
+ if u != v {
+ t.Errorf("EscapeString(%q) = %q, UnescapeString(%q) = %q, want %q", v, e, e, u, v)
+ }
+
+ // As per the documentation, this isn't always equal to v, so it makes
+ // no sense to check for equality. It can still be interesting to find
+ // panics in it though.
+ EscapeString(UnescapeString(v))
+ })
+}
diff --git a/go/src/image/decode_example_test.go b/go/src/image/decode_example_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..252ac868c0fc6cba22ee80ed4f98b76adf37a0ab
--- /dev/null
+++ b/go/src/image/decode_example_test.go
@@ -0,0 +1,149 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This example demonstrates decoding a JPEG image and examining its pixels.
+package image_test
+
+import (
+ "encoding/base64"
+ "fmt"
+ "image"
+ "log"
+ "strings"
+
+ // Package image/jpeg is not used explicitly in the code below,
+ // but is imported for its initialization side-effect, which allows
+ // image.Decode to understand JPEG formatted images. Uncomment these
+ // two lines to also understand GIF and PNG images:
+ // _ "image/gif"
+ // _ "image/png"
+ _ "image/jpeg"
+)
+
+func Example_decodeConfig() {
+ reader := base64.NewDecoder(base64.StdEncoding, strings.NewReader(data))
+ config, format, err := image.DecodeConfig(reader)
+ if err != nil {
+ log.Fatal(err)
+ }
+ fmt.Println("Width:", config.Width, "Height:", config.Height, "Format:", format)
+}
+
+func Example() {
+ // Decode the JPEG data. If reading from file, create a reader with
+ //
+ // reader, err := os.Open("testdata/video-001.q50.420.jpeg")
+ // if err != nil {
+ // log.Fatal(err)
+ // }
+ // defer reader.Close()
+ reader := base64.NewDecoder(base64.StdEncoding, strings.NewReader(data))
+ m, _, err := image.Decode(reader)
+ if err != nil {
+ log.Fatal(err)
+ }
+ bounds := m.Bounds()
+
+ // Calculate a 16-bin histogram for m's red, green, blue and alpha components.
+ //
+ // An image's bounds do not necessarily start at (0, 0), so the two loops start
+ // at bounds.Min.Y and bounds.Min.X. Looping over Y first and X second is more
+ // likely to result in better memory access patterns than X first and Y second.
+ var histogram [16][4]int
+ for y := bounds.Min.Y; y < bounds.Max.Y; y++ {
+ for x := bounds.Min.X; x < bounds.Max.X; x++ {
+ r, g, b, a := m.At(x, y).RGBA()
+ // A color's RGBA method returns values in the range [0, 65535].
+ // Shifting by 12 reduces this to the range [0, 15].
+ histogram[r>>12][0]++
+ histogram[g>>12][1]++
+ histogram[b>>12][2]++
+ histogram[a>>12][3]++
+ }
+ }
+
+ // Print the results.
+ fmt.Printf("%-14s %6s %6s %6s %6s\n", "bin", "red", "green", "blue", "alpha")
+ for i, x := range histogram {
+ fmt.Printf("0x%04x-0x%04x: %6d %6d %6d %6d\n", i<<12, (i+1)<<12-1, x[0], x[1], x[2], x[3])
+ }
+ // Output:
+ // bin red green blue alpha
+ // 0x0000-0x0fff: 362 793 7245 0
+ // 0x1000-0x1fff: 648 2963 1036 0
+ // 0x2000-0x2fff: 1072 2301 977 0
+ // 0x3000-0x3fff: 819 2266 982 0
+ // 0x4000-0x4fff: 537 1303 541 0
+ // 0x5000-0x5fff: 321 964 261 0
+ // 0x6000-0x6fff: 321 375 177 0
+ // 0x7000-0x7fff: 599 278 213 0
+ // 0x8000-0x8fff: 3478 228 275 0
+ // 0x9000-0x9fff: 2260 233 328 0
+ // 0xa000-0xafff: 921 282 374 0
+ // 0xb000-0xbfff: 322 335 395 0
+ // 0xc000-0xcfff: 228 388 299 0
+ // 0xd000-0xdfff: 261 415 277 0
+ // 0xe000-0xefff: 516 423 297 0
+ // 0xf000-0xffff: 2785 1903 1773 15450
+}
+
+const data = `
+/9j/4AAQSkZJRgABAQIAHAAcAAD/2wBDABALDA4MChAODQ4SERATGCgaGBYWGDEjJR0oOjM9PDkzODdA
+SFxOQERXRTc4UG1RV19iZ2hnPk1xeXBkeFxlZ2P/2wBDARESEhgVGC8aGi9jQjhCY2NjY2NjY2NjY2Nj
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+HwAAAQUBAQEBAQEAAAAAAAAAAAECAwQFBgcICQoL/8QAtRAAAgEDAwIEAwUFBAQAAAF9AQIDAAQRBRIh
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+x8jJytLT1NXW19jZ2uHi4+Tl5ufo6erx8vP09fb3+Pn6/8QAHwEAAwEBAQEBAQEBAQAAAAAAAAECAwQF
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+X/PoP++2/wAan6rAr6wzkWt0II+1Rc/7Lf4Vd1eeCSKBbdZDdShYoiZNoyfY10P/AAj2lf8APmP++2/x
+oPh/SjKspsozIuNrZORjp3qo0FHYPb3OZt7ae3SzjuItsiRSAgnccl/UA+3Q1yNjKLR4ZZYY5VD7tkv3
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+N0oy1RzOtaN/Y1tHNFO06u+zYy4I4Jzx9KKveJblXuordSGES5b6n/62PzorKVdp2LjQTVyWz8UWEWlq
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+GHk245CZ6/X1qPTLq40q+W5t2QybSpDAkEEc55/zilk5k2r91eKhLDzWz2rpsczbbuemeD76fUNG865I
+MiysmQMZAAwa3a5j4ftu0ByP+fh/5CulkLLG7INzhSVHqe1Fh3uOoqn9qQQxyhndmHIxwOmSR2xQ13KD
+KoiBZOV9JBnt707MVy5RWdNdy7wRGf3bfMinnO1jg+vY03WXLaJO3mhQ20b0zwpYf0qlG7S7icrJs08U
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+b+VP0bnSrb94ZMJgOecj1rl/GfidUE2k2gy5+SeQjgA/wj3rlas2jdao48qrjLAGkSKPk4Gc1WMj92I+
+lIJnU8OfxPWo5inBokmtQTmM4OOh71b0q6vbFmWCbaxHyqQGAP0PT8KhSTzVyo5ocSKA5VfTOTmqsmRd
+pl99XjPzThzK3zOeOSeveirNmkgg/fIpYsTkYORxRXmzlTjJqx6EVUcU7mhkKCzdAK59QI9zYxtG1fYU
+UVtgtmY4nZEa8Ak9aqFv3rfSiiu1nMeifDv/AJF+T/r4f+QrqqKKQwzQenNFFMCOKFIgNuThdoJ5OPSk
+ubeK6t3gnXdG4wwziiii/UTKMOg6dbzJLFE4dSCP3rEdeOM8805tDsGMvySgSsS6rM6gk9eAcUUVftZt
+3uyVGNthuq3Eei6DK8H7sRR7YuMgHtXkc8rzTNLM26RyWY+p70UVnLY0iEsUipG7rhZBlDkc1HgYoorM
+0HwyBXGeRjmrcUhMg2ghezd//rUUVcTKW5s2jZtY/QDaOKKKK8ip8bPRj8KP/9k=
+`
diff --git a/go/src/image/decode_test.go b/go/src/image/decode_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..2b3ff6ba582662c11c4e19392741513e584e0b38
--- /dev/null
+++ b/go/src/image/decode_test.go
@@ -0,0 +1,135 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package image_test
+
+import (
+ "bufio"
+ "fmt"
+ "image"
+ "image/color"
+ "os"
+ "testing"
+
+ _ "image/gif"
+ _ "image/jpeg"
+ _ "image/png"
+)
+
+type imageTest struct {
+ goldenFilename string
+ filename string
+ tolerance int
+}
+
+var imageTests = []imageTest{
+ {"testdata/video-001.png", "testdata/video-001.png", 0},
+ // GIF images are restricted to a 256-color palette and the conversion
+ // to GIF loses significant image quality.
+ {"testdata/video-001.png", "testdata/video-001.gif", 64 << 8},
+ {"testdata/video-001.png", "testdata/video-001.interlaced.gif", 64 << 8},
+ {"testdata/video-001.png", "testdata/video-001.5bpp.gif", 128 << 8},
+ // JPEG is a lossy format and hence needs a non-zero tolerance.
+ {"testdata/video-001.png", "testdata/video-001.jpeg", 8 << 8},
+ {"testdata/video-001.png", "testdata/video-001.progressive.jpeg", 8 << 8},
+ {"testdata/video-001.221212.png", "testdata/video-001.221212.jpeg", 8 << 8},
+ {"testdata/video-001.cmyk.png", "testdata/video-001.cmyk.jpeg", 8 << 8},
+ {"testdata/video-001.rgb.png", "testdata/video-001.rgb.jpeg", 8 << 8},
+ {"testdata/video-001.progressive.truncated.png", "testdata/video-001.progressive.truncated.jpeg", 8 << 8},
+ // Grayscale images.
+ {"testdata/video-005.gray.png", "testdata/video-005.gray.jpeg", 8 << 8},
+ {"testdata/video-005.gray.png", "testdata/video-005.gray.png", 0},
+}
+
+func decode(filename string) (image.Image, string, error) {
+ f, err := os.Open(filename)
+ if err != nil {
+ return nil, "", err
+ }
+ defer f.Close()
+ return image.Decode(bufio.NewReader(f))
+}
+
+func decodeConfig(filename string) (image.Config, string, error) {
+ f, err := os.Open(filename)
+ if err != nil {
+ return image.Config{}, "", err
+ }
+ defer f.Close()
+ return image.DecodeConfig(bufio.NewReader(f))
+}
+
+func delta(u0, u1 uint32) int {
+ d := int(u0) - int(u1)
+ if d < 0 {
+ return -d
+ }
+ return d
+}
+
+func withinTolerance(c0, c1 color.Color, tolerance int) bool {
+ r0, g0, b0, a0 := c0.RGBA()
+ r1, g1, b1, a1 := c1.RGBA()
+ r := delta(r0, r1)
+ g := delta(g0, g1)
+ b := delta(b0, b1)
+ a := delta(a0, a1)
+ return r <= tolerance && g <= tolerance && b <= tolerance && a <= tolerance
+}
+
+func TestDecode(t *testing.T) {
+ rgba := func(c color.Color) string {
+ r, g, b, a := c.RGBA()
+ return fmt.Sprintf("rgba = 0x%04x, 0x%04x, 0x%04x, 0x%04x for %T%v", r, g, b, a, c, c)
+ }
+
+ golden := make(map[string]image.Image)
+loop:
+ for _, it := range imageTests {
+ g := golden[it.goldenFilename]
+ if g == nil {
+ var err error
+ g, _, err = decode(it.goldenFilename)
+ if err != nil {
+ t.Errorf("%s: %v", it.goldenFilename, err)
+ continue loop
+ }
+ golden[it.goldenFilename] = g
+ }
+ m, imageFormat, err := decode(it.filename)
+ if err != nil {
+ t.Errorf("%s: %v", it.filename, err)
+ continue loop
+ }
+ b := g.Bounds()
+ if !b.Eq(m.Bounds()) {
+ t.Errorf("%s: got bounds %v want %v", it.filename, m.Bounds(), b)
+ continue loop
+ }
+ for y := b.Min.Y; y < b.Max.Y; y++ {
+ for x := b.Min.X; x < b.Max.X; x++ {
+ if !withinTolerance(g.At(x, y), m.At(x, y), it.tolerance) {
+ t.Errorf("%s: at (%d, %d):\ngot %v\nwant %v",
+ it.filename, x, y, rgba(m.At(x, y)), rgba(g.At(x, y)))
+ continue loop
+ }
+ }
+ }
+ if imageFormat == "gif" {
+ // Each frame of a GIF can have a frame-local palette override the
+ // GIF-global palette. Thus, image.Decode can yield a different ColorModel
+ // than image.DecodeConfig.
+ continue
+ }
+ c, _, err := decodeConfig(it.filename)
+ if err != nil {
+ t.Errorf("%s: %v", it.filename, err)
+ continue loop
+ }
+ if m.ColorModel() != c.ColorModel {
+ t.Errorf("%s: color models differ", it.filename)
+ continue loop
+ }
+ }
+}
diff --git a/go/src/image/format.go b/go/src/image/format.go
new file mode 100644
index 0000000000000000000000000000000000000000..7426afb3e69e906406ad69ed68f051366d18a0e8
--- /dev/null
+++ b/go/src/image/format.go
@@ -0,0 +1,109 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package image
+
+import (
+ "bufio"
+ "errors"
+ "io"
+ "sync"
+ "sync/atomic"
+)
+
+// ErrFormat indicates that decoding encountered an unknown format.
+var ErrFormat = errors.New("image: unknown format")
+
+// A format holds an image format's name, magic header and how to decode it.
+type format struct {
+ name, magic string
+ decode func(io.Reader) (Image, error)
+ decodeConfig func(io.Reader) (Config, error)
+}
+
+// Formats is the list of registered formats.
+var (
+ formatsMu sync.Mutex
+ atomicFormats atomic.Value
+)
+
+// RegisterFormat registers an image format for use by [Decode].
+// Name is the name of the format, like "jpeg" or "png".
+// Magic is the magic prefix that identifies the format's encoding. The magic
+// string can contain "?" wildcards that each match any one byte.
+// [Decode] is the function that decodes the encoded image.
+// [DecodeConfig] is the function that decodes just its configuration.
+func RegisterFormat(name, magic string, decode func(io.Reader) (Image, error), decodeConfig func(io.Reader) (Config, error)) {
+ formatsMu.Lock()
+ formats, _ := atomicFormats.Load().([]format)
+ atomicFormats.Store(append(formats, format{name, magic, decode, decodeConfig}))
+ formatsMu.Unlock()
+}
+
+// A reader is an io.Reader that can also peek ahead.
+type reader interface {
+ io.Reader
+ Peek(int) ([]byte, error)
+}
+
+// asReader converts an io.Reader to a reader.
+func asReader(r io.Reader) reader {
+ if rr, ok := r.(reader); ok {
+ return rr
+ }
+ return bufio.NewReader(r)
+}
+
+// match reports whether magic matches b. Magic may contain "?" wildcards.
+func match(magic string, b []byte) bool {
+ if len(magic) != len(b) {
+ return false
+ }
+ for i, c := range b {
+ if magic[i] != c && magic[i] != '?' {
+ return false
+ }
+ }
+ return true
+}
+
+// sniff determines the format of r's data.
+func sniff(r reader) format {
+ formats, _ := atomicFormats.Load().([]format)
+ for _, f := range formats {
+ b, err := r.Peek(len(f.magic))
+ if err == nil && match(f.magic, b) {
+ return f
+ }
+ }
+ return format{}
+}
+
+// Decode decodes an image that has been encoded in a registered format.
+// The string returned is the format name used during format registration.
+// Format registration is typically done by an init function in the codec-
+// specific package.
+func Decode(r io.Reader) (Image, string, error) {
+ rr := asReader(r)
+ f := sniff(rr)
+ if f.decode == nil {
+ return nil, "", ErrFormat
+ }
+ m, err := f.decode(rr)
+ return m, f.name, err
+}
+
+// DecodeConfig decodes the color model and dimensions of an image that has
+// been encoded in a registered format. The string returned is the format name
+// used during format registration. Format registration is typically done by
+// an init function in the codec-specific package.
+func DecodeConfig(r io.Reader) (Config, string, error) {
+ rr := asReader(r)
+ f := sniff(rr)
+ if f.decodeConfig == nil {
+ return Config{}, "", ErrFormat
+ }
+ c, err := f.decodeConfig(rr)
+ return c, f.name, err
+}
diff --git a/go/src/image/geom.go b/go/src/image/geom.go
new file mode 100644
index 0000000000000000000000000000000000000000..4ee14bff980cf0fde464731f0fb9041215a42631
--- /dev/null
+++ b/go/src/image/geom.go
@@ -0,0 +1,317 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package image
+
+import (
+ "image/color"
+ "math/bits"
+ "strconv"
+)
+
+// A Point is an X, Y coordinate pair. The axes increase right and down.
+type Point struct {
+ X, Y int
+}
+
+// String returns a string representation of p like "(3,4)".
+func (p Point) String() string {
+ return "(" + strconv.Itoa(p.X) + "," + strconv.Itoa(p.Y) + ")"
+}
+
+// Add returns the vector p+q.
+func (p Point) Add(q Point) Point {
+ return Point{p.X + q.X, p.Y + q.Y}
+}
+
+// Sub returns the vector p-q.
+func (p Point) Sub(q Point) Point {
+ return Point{p.X - q.X, p.Y - q.Y}
+}
+
+// Mul returns the vector p*k.
+func (p Point) Mul(k int) Point {
+ return Point{p.X * k, p.Y * k}
+}
+
+// Div returns the vector p/k.
+func (p Point) Div(k int) Point {
+ return Point{p.X / k, p.Y / k}
+}
+
+// In reports whether p is in r.
+func (p Point) In(r Rectangle) bool {
+ return r.Min.X <= p.X && p.X < r.Max.X &&
+ r.Min.Y <= p.Y && p.Y < r.Max.Y
+}
+
+// Mod returns the point q in r such that p.X-q.X is a multiple of r's width
+// and p.Y-q.Y is a multiple of r's height.
+func (p Point) Mod(r Rectangle) Point {
+ w, h := r.Dx(), r.Dy()
+ p = p.Sub(r.Min)
+ p.X = p.X % w
+ if p.X < 0 {
+ p.X += w
+ }
+ p.Y = p.Y % h
+ if p.Y < 0 {
+ p.Y += h
+ }
+ return p.Add(r.Min)
+}
+
+// Eq reports whether p and q are equal.
+func (p Point) Eq(q Point) bool {
+ return p == q
+}
+
+// ZP is the zero [Point].
+//
+// Deprecated: Use a literal [image.Point] instead.
+var ZP Point
+
+// Pt is shorthand for [Point]{X, Y}.
+func Pt(X, Y int) Point {
+ return Point{X, Y}
+}
+
+// A Rectangle contains the points with Min.X <= X < Max.X, Min.Y <= Y < Max.Y.
+// It is well-formed if Min.X <= Max.X and likewise for Y. Points are always
+// well-formed. A rectangle's methods always return well-formed outputs for
+// well-formed inputs.
+//
+// A Rectangle is also an [Image] whose bounds are the rectangle itself. At
+// returns color.Opaque for points in the rectangle and color.Transparent
+// otherwise.
+type Rectangle struct {
+ Min, Max Point
+}
+
+// String returns a string representation of r like "(3,4)-(6,5)".
+func (r Rectangle) String() string {
+ return r.Min.String() + "-" + r.Max.String()
+}
+
+// Dx returns r's width.
+func (r Rectangle) Dx() int {
+ return r.Max.X - r.Min.X
+}
+
+// Dy returns r's height.
+func (r Rectangle) Dy() int {
+ return r.Max.Y - r.Min.Y
+}
+
+// Size returns r's width and height.
+func (r Rectangle) Size() Point {
+ return Point{
+ r.Max.X - r.Min.X,
+ r.Max.Y - r.Min.Y,
+ }
+}
+
+// Add returns the rectangle r translated by p.
+func (r Rectangle) Add(p Point) Rectangle {
+ return Rectangle{
+ Point{r.Min.X + p.X, r.Min.Y + p.Y},
+ Point{r.Max.X + p.X, r.Max.Y + p.Y},
+ }
+}
+
+// Sub returns the rectangle r translated by -p.
+func (r Rectangle) Sub(p Point) Rectangle {
+ return Rectangle{
+ Point{r.Min.X - p.X, r.Min.Y - p.Y},
+ Point{r.Max.X - p.X, r.Max.Y - p.Y},
+ }
+}
+
+// Inset returns the rectangle r inset by n, which may be negative. If either
+// of r's dimensions is less than 2*n then an empty rectangle near the center
+// of r will be returned.
+func (r Rectangle) Inset(n int) Rectangle {
+ if r.Dx() < 2*n {
+ r.Min.X = (r.Min.X + r.Max.X) / 2
+ r.Max.X = r.Min.X
+ } else {
+ r.Min.X += n
+ r.Max.X -= n
+ }
+ if r.Dy() < 2*n {
+ r.Min.Y = (r.Min.Y + r.Max.Y) / 2
+ r.Max.Y = r.Min.Y
+ } else {
+ r.Min.Y += n
+ r.Max.Y -= n
+ }
+ return r
+}
+
+// Intersect returns the largest rectangle contained by both r and s. If the
+// two rectangles do not overlap then the zero rectangle will be returned.
+func (r Rectangle) Intersect(s Rectangle) Rectangle {
+ if r.Min.X < s.Min.X {
+ r.Min.X = s.Min.X
+ }
+ if r.Min.Y < s.Min.Y {
+ r.Min.Y = s.Min.Y
+ }
+ if r.Max.X > s.Max.X {
+ r.Max.X = s.Max.X
+ }
+ if r.Max.Y > s.Max.Y {
+ r.Max.Y = s.Max.Y
+ }
+ // Letting r0 and s0 be the values of r and s at the time that the method
+ // is called, this next line is equivalent to:
+ //
+ // if max(r0.Min.X, s0.Min.X) >= min(r0.Max.X, s0.Max.X) || likewiseForY { etc }
+ if r.Empty() {
+ return Rectangle{}
+ }
+ return r
+}
+
+// Union returns the smallest rectangle that contains both r and s.
+func (r Rectangle) Union(s Rectangle) Rectangle {
+ if r.Empty() {
+ return s
+ }
+ if s.Empty() {
+ return r
+ }
+ if r.Min.X > s.Min.X {
+ r.Min.X = s.Min.X
+ }
+ if r.Min.Y > s.Min.Y {
+ r.Min.Y = s.Min.Y
+ }
+ if r.Max.X < s.Max.X {
+ r.Max.X = s.Max.X
+ }
+ if r.Max.Y < s.Max.Y {
+ r.Max.Y = s.Max.Y
+ }
+ return r
+}
+
+// Empty reports whether the rectangle contains no points.
+func (r Rectangle) Empty() bool {
+ return r.Min.X >= r.Max.X || r.Min.Y >= r.Max.Y
+}
+
+// Eq reports whether r and s contain the same set of points. All empty
+// rectangles are considered equal.
+func (r Rectangle) Eq(s Rectangle) bool {
+ return r == s || r.Empty() && s.Empty()
+}
+
+// Overlaps reports whether r and s have a non-empty intersection.
+func (r Rectangle) Overlaps(s Rectangle) bool {
+ return !r.Empty() && !s.Empty() &&
+ r.Min.X < s.Max.X && s.Min.X < r.Max.X &&
+ r.Min.Y < s.Max.Y && s.Min.Y < r.Max.Y
+}
+
+// In reports whether every point in r is in s.
+func (r Rectangle) In(s Rectangle) bool {
+ if r.Empty() {
+ return true
+ }
+ // Note that r.Max is an exclusive bound for r, so that r.In(s)
+ // does not require that r.Max.In(s).
+ return s.Min.X <= r.Min.X && r.Max.X <= s.Max.X &&
+ s.Min.Y <= r.Min.Y && r.Max.Y <= s.Max.Y
+}
+
+// Canon returns the canonical version of r. The returned rectangle has minimum
+// and maximum coordinates swapped if necessary so that it is well-formed.
+func (r Rectangle) Canon() Rectangle {
+ if r.Max.X < r.Min.X {
+ r.Min.X, r.Max.X = r.Max.X, r.Min.X
+ }
+ if r.Max.Y < r.Min.Y {
+ r.Min.Y, r.Max.Y = r.Max.Y, r.Min.Y
+ }
+ return r
+}
+
+// At implements the [Image] interface.
+func (r Rectangle) At(x, y int) color.Color {
+ if (Point{x, y}).In(r) {
+ return color.Opaque
+ }
+ return color.Transparent
+}
+
+// RGBA64At implements the [RGBA64Image] interface.
+func (r Rectangle) RGBA64At(x, y int) color.RGBA64 {
+ if (Point{x, y}).In(r) {
+ return color.RGBA64{0xffff, 0xffff, 0xffff, 0xffff}
+ }
+ return color.RGBA64{}
+}
+
+// Bounds implements the [Image] interface.
+func (r Rectangle) Bounds() Rectangle {
+ return r
+}
+
+// ColorModel implements the [Image] interface.
+func (r Rectangle) ColorModel() color.Model {
+ return color.Alpha16Model
+}
+
+// ZR is the zero [Rectangle].
+//
+// Deprecated: Use a literal [image.Rectangle] instead.
+var ZR Rectangle
+
+// Rect is shorthand for [Rectangle]{Pt(x0, y0), [Pt](x1, y1)}. The returned
+// rectangle has minimum and maximum coordinates swapped if necessary so that
+// it is well-formed.
+func Rect(x0, y0, x1, y1 int) Rectangle {
+ if x0 > x1 {
+ x0, x1 = x1, x0
+ }
+ if y0 > y1 {
+ y0, y1 = y1, y0
+ }
+ return Rectangle{Point{x0, y0}, Point{x1, y1}}
+}
+
+// mul3NonNeg returns (x * y * z), unless at least one argument is negative or
+// if the computation overflows the int type, in which case it returns -1.
+func mul3NonNeg(x int, y int, z int) int {
+ if (x < 0) || (y < 0) || (z < 0) {
+ return -1
+ }
+ hi, lo := bits.Mul64(uint64(x), uint64(y))
+ if hi != 0 {
+ return -1
+ }
+ hi, lo = bits.Mul64(lo, uint64(z))
+ if hi != 0 {
+ return -1
+ }
+ a := int(lo)
+ if (a < 0) || (uint64(a) != lo) {
+ return -1
+ }
+ return a
+}
+
+// add2NonNeg returns (x + y), unless at least one argument is negative or if
+// the computation overflows the int type, in which case it returns -1.
+func add2NonNeg(x int, y int) int {
+ if (x < 0) || (y < 0) {
+ return -1
+ }
+ a := x + y
+ if a < 0 {
+ return -1
+ }
+ return a
+}
diff --git a/go/src/image/geom_test.go b/go/src/image/geom_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..9fede027218c31e54a478cd6a40bd4e34fac577b
--- /dev/null
+++ b/go/src/image/geom_test.go
@@ -0,0 +1,116 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package image
+
+import (
+ "fmt"
+ "testing"
+)
+
+func TestRectangle(t *testing.T) {
+ // in checks that every point in f is in g.
+ in := func(f, g Rectangle) error {
+ if !f.In(g) {
+ return fmt.Errorf("f=%s, f.In(%s): got false, want true", f, g)
+ }
+ for y := f.Min.Y; y < f.Max.Y; y++ {
+ for x := f.Min.X; x < f.Max.X; x++ {
+ p := Point{x, y}
+ if !p.In(g) {
+ return fmt.Errorf("p=%s, p.In(%s): got false, want true", p, g)
+ }
+ }
+ }
+ return nil
+ }
+
+ rects := []Rectangle{
+ Rect(0, 0, 10, 10),
+ Rect(10, 0, 20, 10),
+ Rect(1, 2, 3, 4),
+ Rect(4, 6, 10, 10),
+ Rect(2, 3, 12, 5),
+ Rect(-1, -2, 0, 0),
+ Rect(-1, -2, 4, 6),
+ Rect(-10, -20, 30, 40),
+ Rect(8, 8, 8, 8),
+ Rect(88, 88, 88, 88),
+ Rect(6, 5, 4, 3),
+ }
+
+ // r.Eq(s) should be equivalent to every point in r being in s, and every
+ // point in s being in r.
+ for _, r := range rects {
+ for _, s := range rects {
+ got := r.Eq(s)
+ want := in(r, s) == nil && in(s, r) == nil
+ if got != want {
+ t.Errorf("Eq: r=%s, s=%s: got %t, want %t", r, s, got, want)
+ }
+ }
+ }
+
+ // The intersection should be the largest rectangle a such that every point
+ // in a is both in r and in s.
+ for _, r := range rects {
+ for _, s := range rects {
+ a := r.Intersect(s)
+ if err := in(a, r); err != nil {
+ t.Errorf("Intersect: r=%s, s=%s, a=%s, a not in r: %v", r, s, a, err)
+ }
+ if err := in(a, s); err != nil {
+ t.Errorf("Intersect: r=%s, s=%s, a=%s, a not in s: %v", r, s, a, err)
+ }
+ if isZero, overlaps := a == (Rectangle{}), r.Overlaps(s); isZero == overlaps {
+ t.Errorf("Intersect: r=%s, s=%s, a=%s: isZero=%t same as overlaps=%t",
+ r, s, a, isZero, overlaps)
+ }
+ largerThanA := [4]Rectangle{a, a, a, a}
+ largerThanA[0].Min.X--
+ largerThanA[1].Min.Y--
+ largerThanA[2].Max.X++
+ largerThanA[3].Max.Y++
+ for i, b := range largerThanA {
+ if b.Empty() {
+ // b isn't actually larger than a.
+ continue
+ }
+ if in(b, r) == nil && in(b, s) == nil {
+ t.Errorf("Intersect: r=%s, s=%s, a=%s, b=%s, i=%d: intersection could be larger",
+ r, s, a, b, i)
+ }
+ }
+ }
+ }
+
+ // The union should be the smallest rectangle a such that every point in r
+ // is in a and every point in s is in a.
+ for _, r := range rects {
+ for _, s := range rects {
+ a := r.Union(s)
+ if err := in(r, a); err != nil {
+ t.Errorf("Union: r=%s, s=%s, a=%s, r not in a: %v", r, s, a, err)
+ }
+ if err := in(s, a); err != nil {
+ t.Errorf("Union: r=%s, s=%s, a=%s, s not in a: %v", r, s, a, err)
+ }
+ if a.Empty() {
+ // You can't get any smaller than a.
+ continue
+ }
+ smallerThanA := [4]Rectangle{a, a, a, a}
+ smallerThanA[0].Min.X++
+ smallerThanA[1].Min.Y++
+ smallerThanA[2].Max.X--
+ smallerThanA[3].Max.Y--
+ for i, b := range smallerThanA {
+ if in(r, b) == nil && in(s, b) == nil {
+ t.Errorf("Union: r=%s, s=%s, a=%s, b=%s, i=%d: union could be smaller",
+ r, s, a, b, i)
+ }
+ }
+ }
+ }
+}
diff --git a/go/src/image/image.go b/go/src/image/image.go
new file mode 100644
index 0000000000000000000000000000000000000000..2cc94075b29ed3286c79c7857ee8fa74340c557c
--- /dev/null
+++ b/go/src/image/image.go
@@ -0,0 +1,1289 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package image implements a basic 2-D image library.
+//
+// The fundamental interface is called [Image]. An [Image] contains colors, which
+// are described in the image/color package.
+//
+// Values of the [Image] interface are created either by calling functions such
+// as [NewRGBA] and [NewPaletted], or by calling [Decode] on an [io.Reader] containing
+// image data in a format such as GIF, JPEG or PNG. Decoding any particular
+// image format requires the prior registration of a decoder function.
+// Registration is typically automatic as a side effect of initializing that
+// format's package so that, to decode a PNG image, it suffices to have
+//
+// import _ "image/png"
+//
+// in a program's main package. The _ means to import a package purely for its
+// initialization side effects.
+//
+// See "The Go image package" for more details:
+// https://golang.org/doc/articles/image_package.html
+//
+// # Security Considerations
+//
+// The image package can be used to parse arbitrarily large images, which can
+// cause resource exhaustion on machines which do not have enough memory to
+// store them. When operating on arbitrary images, [DecodeConfig] should be called
+// before [Decode], so that the program can decide whether the image, as defined
+// in the returned header, can be safely decoded with the available resources. A
+// call to [Decode] which produces an extremely large image, as defined in the
+// header returned by [DecodeConfig], is not considered a security issue,
+// regardless of whether the image is itself malformed or not. A call to
+// [DecodeConfig] which returns a header which does not match the image returned
+// by [Decode] may be considered a security issue, and should be reported per the
+// [Go Security Policy].
+//
+// [Go Security Policy]: https://go.dev/security/policy
+package image
+
+import (
+ "image/color"
+)
+
+// Config holds an image's color model and dimensions.
+type Config struct {
+ ColorModel color.Model
+ Width, Height int
+}
+
+// Image is a finite rectangular grid of [color.Color] values taken from a color
+// model.
+type Image interface {
+ // ColorModel returns the Image's color model.
+ ColorModel() color.Model
+ // Bounds returns the domain for which At can return non-zero color.
+ // The bounds do not necessarily contain the point (0, 0).
+ Bounds() Rectangle
+ // At returns the color of the pixel at (x, y).
+ // At(Bounds().Min.X, Bounds().Min.Y) returns the upper-left pixel of the grid.
+ // At(Bounds().Max.X-1, Bounds().Max.Y-1) returns the lower-right one.
+ At(x, y int) color.Color
+}
+
+// RGBA64Image is an [Image] whose pixels can be converted directly to a
+// color.RGBA64.
+type RGBA64Image interface {
+ // RGBA64At returns the RGBA64 color of the pixel at (x, y). It is
+ // equivalent to calling At(x, y).RGBA() and converting the resulting
+ // 32-bit return values to a color.RGBA64, but it can avoid allocations
+ // from converting concrete color types to the color.Color interface type.
+ RGBA64At(x, y int) color.RGBA64
+ Image
+}
+
+// PalettedImage is an image whose colors may come from a limited palette.
+// If m is a PalettedImage and m.ColorModel() returns a [color.Palette] p,
+// then m.At(x, y) should be equivalent to p[m.ColorIndexAt(x, y)]. If m's
+// color model is not a color.Palette, then ColorIndexAt's behavior is
+// undefined.
+type PalettedImage interface {
+ // ColorIndexAt returns the palette index of the pixel at (x, y).
+ ColorIndexAt(x, y int) uint8
+ Image
+}
+
+// pixelBufferLength returns the length of the []uint8 typed Pix slice field
+// for the NewXxx functions. Conceptually, this is just (bpp * width * height),
+// but this function panics if at least one of those is negative or if the
+// computation would overflow the int type.
+//
+// This panics instead of returning an error because of backwards
+// compatibility. The NewXxx functions do not return an error.
+func pixelBufferLength(bytesPerPixel int, r Rectangle, imageTypeName string) int {
+ totalLength := mul3NonNeg(bytesPerPixel, r.Dx(), r.Dy())
+ if totalLength < 0 {
+ panic("image: New" + imageTypeName + " Rectangle has huge or negative dimensions")
+ }
+ return totalLength
+}
+
+// RGBA is an in-memory image whose At method returns [color.RGBA] values.
+type RGBA struct {
+ // Pix holds the image's pixels, in R, G, B, A order. The pixel at
+ // (x, y) starts at Pix[(y-Rect.Min.Y)*Stride + (x-Rect.Min.X)*4].
+ Pix []uint8
+ // Stride is the Pix stride (in bytes) between vertically adjacent pixels.
+ Stride int
+ // Rect is the image's bounds.
+ Rect Rectangle
+}
+
+func (p *RGBA) ColorModel() color.Model { return color.RGBAModel }
+
+func (p *RGBA) Bounds() Rectangle { return p.Rect }
+
+func (p *RGBA) At(x, y int) color.Color {
+ return p.RGBAAt(x, y)
+}
+
+func (p *RGBA) RGBA64At(x, y int) color.RGBA64 {
+ if !(Point{x, y}.In(p.Rect)) {
+ return color.RGBA64{}
+ }
+ i := p.PixOffset(x, y)
+ s := p.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857
+ r := uint16(s[0])
+ g := uint16(s[1])
+ b := uint16(s[2])
+ a := uint16(s[3])
+ return color.RGBA64{
+ (r << 8) | r,
+ (g << 8) | g,
+ (b << 8) | b,
+ (a << 8) | a,
+ }
+}
+
+func (p *RGBA) RGBAAt(x, y int) color.RGBA {
+ if !(Point{x, y}.In(p.Rect)) {
+ return color.RGBA{}
+ }
+ i := p.PixOffset(x, y)
+ s := p.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857
+ return color.RGBA{s[0], s[1], s[2], s[3]}
+}
+
+// PixOffset returns the index of the first element of Pix that corresponds to
+// the pixel at (x, y).
+func (p *RGBA) PixOffset(x, y int) int {
+ return (y-p.Rect.Min.Y)*p.Stride + (x-p.Rect.Min.X)*4
+}
+
+func (p *RGBA) Set(x, y int, c color.Color) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ c1 := color.RGBAModel.Convert(c).(color.RGBA)
+ s := p.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857
+ s[0] = c1.R
+ s[1] = c1.G
+ s[2] = c1.B
+ s[3] = c1.A
+}
+
+func (p *RGBA) SetRGBA64(x, y int, c color.RGBA64) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ s := p.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857
+ s[0] = uint8(c.R >> 8)
+ s[1] = uint8(c.G >> 8)
+ s[2] = uint8(c.B >> 8)
+ s[3] = uint8(c.A >> 8)
+}
+
+func (p *RGBA) SetRGBA(x, y int, c color.RGBA) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ s := p.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857
+ s[0] = c.R
+ s[1] = c.G
+ s[2] = c.B
+ s[3] = c.A
+}
+
+// SubImage returns an image representing the portion of the image p visible
+// through r. The returned value shares pixels with the original image.
+func (p *RGBA) SubImage(r Rectangle) Image {
+ r = r.Intersect(p.Rect)
+ // If r1 and r2 are Rectangles, r1.Intersect(r2) is not guaranteed to be inside
+ // either r1 or r2 if the intersection is empty. Without explicitly checking for
+ // this, the Pix[i:] expression below can panic.
+ if r.Empty() {
+ return &RGBA{}
+ }
+ i := p.PixOffset(r.Min.X, r.Min.Y)
+ return &RGBA{
+ Pix: p.Pix[i:],
+ Stride: p.Stride,
+ Rect: r,
+ }
+}
+
+// Opaque scans the entire image and reports whether it is fully opaque.
+func (p *RGBA) Opaque() bool {
+ if p.Rect.Empty() {
+ return true
+ }
+ i0, i1 := 3, p.Rect.Dx()*4
+ for y := p.Rect.Min.Y; y < p.Rect.Max.Y; y++ {
+ for i := i0; i < i1; i += 4 {
+ if p.Pix[i] != 0xff {
+ return false
+ }
+ }
+ i0 += p.Stride
+ i1 += p.Stride
+ }
+ return true
+}
+
+// NewRGBA returns a new [RGBA] image with the given bounds.
+func NewRGBA(r Rectangle) *RGBA {
+ return &RGBA{
+ Pix: make([]uint8, pixelBufferLength(4, r, "RGBA")),
+ Stride: 4 * r.Dx(),
+ Rect: r,
+ }
+}
+
+// RGBA64 is an in-memory image whose At method returns [color.RGBA64] values.
+type RGBA64 struct {
+ // Pix holds the image's pixels, in R, G, B, A order and big-endian format. The pixel at
+ // (x, y) starts at Pix[(y-Rect.Min.Y)*Stride + (x-Rect.Min.X)*8].
+ Pix []uint8
+ // Stride is the Pix stride (in bytes) between vertically adjacent pixels.
+ Stride int
+ // Rect is the image's bounds.
+ Rect Rectangle
+}
+
+func (p *RGBA64) ColorModel() color.Model { return color.RGBA64Model }
+
+func (p *RGBA64) Bounds() Rectangle { return p.Rect }
+
+func (p *RGBA64) At(x, y int) color.Color {
+ return p.RGBA64At(x, y)
+}
+
+func (p *RGBA64) RGBA64At(x, y int) color.RGBA64 {
+ if !(Point{x, y}.In(p.Rect)) {
+ return color.RGBA64{}
+ }
+ i := p.PixOffset(x, y)
+ s := p.Pix[i : i+8 : i+8] // Small cap improves performance, see https://golang.org/issue/27857
+ return color.RGBA64{
+ uint16(s[0])<<8 | uint16(s[1]),
+ uint16(s[2])<<8 | uint16(s[3]),
+ uint16(s[4])<<8 | uint16(s[5]),
+ uint16(s[6])<<8 | uint16(s[7]),
+ }
+}
+
+// PixOffset returns the index of the first element of Pix that corresponds to
+// the pixel at (x, y).
+func (p *RGBA64) PixOffset(x, y int) int {
+ return (y-p.Rect.Min.Y)*p.Stride + (x-p.Rect.Min.X)*8
+}
+
+func (p *RGBA64) Set(x, y int, c color.Color) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ c1 := color.RGBA64Model.Convert(c).(color.RGBA64)
+ s := p.Pix[i : i+8 : i+8] // Small cap improves performance, see https://golang.org/issue/27857
+ s[0] = uint8(c1.R >> 8)
+ s[1] = uint8(c1.R)
+ s[2] = uint8(c1.G >> 8)
+ s[3] = uint8(c1.G)
+ s[4] = uint8(c1.B >> 8)
+ s[5] = uint8(c1.B)
+ s[6] = uint8(c1.A >> 8)
+ s[7] = uint8(c1.A)
+}
+
+func (p *RGBA64) SetRGBA64(x, y int, c color.RGBA64) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ s := p.Pix[i : i+8 : i+8] // Small cap improves performance, see https://golang.org/issue/27857
+ s[0] = uint8(c.R >> 8)
+ s[1] = uint8(c.R)
+ s[2] = uint8(c.G >> 8)
+ s[3] = uint8(c.G)
+ s[4] = uint8(c.B >> 8)
+ s[5] = uint8(c.B)
+ s[6] = uint8(c.A >> 8)
+ s[7] = uint8(c.A)
+}
+
+// SubImage returns an image representing the portion of the image p visible
+// through r. The returned value shares pixels with the original image.
+func (p *RGBA64) SubImage(r Rectangle) Image {
+ r = r.Intersect(p.Rect)
+ // If r1 and r2 are Rectangles, r1.Intersect(r2) is not guaranteed to be inside
+ // either r1 or r2 if the intersection is empty. Without explicitly checking for
+ // this, the Pix[i:] expression below can panic.
+ if r.Empty() {
+ return &RGBA64{}
+ }
+ i := p.PixOffset(r.Min.X, r.Min.Y)
+ return &RGBA64{
+ Pix: p.Pix[i:],
+ Stride: p.Stride,
+ Rect: r,
+ }
+}
+
+// Opaque scans the entire image and reports whether it is fully opaque.
+func (p *RGBA64) Opaque() bool {
+ if p.Rect.Empty() {
+ return true
+ }
+ i0, i1 := 6, p.Rect.Dx()*8
+ for y := p.Rect.Min.Y; y < p.Rect.Max.Y; y++ {
+ for i := i0; i < i1; i += 8 {
+ if p.Pix[i+0] != 0xff || p.Pix[i+1] != 0xff {
+ return false
+ }
+ }
+ i0 += p.Stride
+ i1 += p.Stride
+ }
+ return true
+}
+
+// NewRGBA64 returns a new [RGBA64] image with the given bounds.
+func NewRGBA64(r Rectangle) *RGBA64 {
+ return &RGBA64{
+ Pix: make([]uint8, pixelBufferLength(8, r, "RGBA64")),
+ Stride: 8 * r.Dx(),
+ Rect: r,
+ }
+}
+
+// NRGBA is an in-memory image whose At method returns [color.NRGBA] values.
+type NRGBA struct {
+ // Pix holds the image's pixels, in R, G, B, A order. The pixel at
+ // (x, y) starts at Pix[(y-Rect.Min.Y)*Stride + (x-Rect.Min.X)*4].
+ Pix []uint8
+ // Stride is the Pix stride (in bytes) between vertically adjacent pixels.
+ Stride int
+ // Rect is the image's bounds.
+ Rect Rectangle
+}
+
+func (p *NRGBA) ColorModel() color.Model { return color.NRGBAModel }
+
+func (p *NRGBA) Bounds() Rectangle { return p.Rect }
+
+func (p *NRGBA) At(x, y int) color.Color {
+ return p.NRGBAAt(x, y)
+}
+
+func (p *NRGBA) RGBA64At(x, y int) color.RGBA64 {
+ r, g, b, a := p.NRGBAAt(x, y).RGBA()
+ return color.RGBA64{uint16(r), uint16(g), uint16(b), uint16(a)}
+}
+
+func (p *NRGBA) NRGBAAt(x, y int) color.NRGBA {
+ if !(Point{x, y}.In(p.Rect)) {
+ return color.NRGBA{}
+ }
+ i := p.PixOffset(x, y)
+ s := p.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857
+ return color.NRGBA{s[0], s[1], s[2], s[3]}
+}
+
+// PixOffset returns the index of the first element of Pix that corresponds to
+// the pixel at (x, y).
+func (p *NRGBA) PixOffset(x, y int) int {
+ return (y-p.Rect.Min.Y)*p.Stride + (x-p.Rect.Min.X)*4
+}
+
+func (p *NRGBA) Set(x, y int, c color.Color) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ c1 := color.NRGBAModel.Convert(c).(color.NRGBA)
+ s := p.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857
+ s[0] = c1.R
+ s[1] = c1.G
+ s[2] = c1.B
+ s[3] = c1.A
+}
+
+func (p *NRGBA) SetRGBA64(x, y int, c color.RGBA64) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ r, g, b, a := uint32(c.R), uint32(c.G), uint32(c.B), uint32(c.A)
+ if (a != 0) && (a != 0xffff) {
+ r = (r * 0xffff) / a
+ g = (g * 0xffff) / a
+ b = (b * 0xffff) / a
+ }
+ i := p.PixOffset(x, y)
+ s := p.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857
+ s[0] = uint8(r >> 8)
+ s[1] = uint8(g >> 8)
+ s[2] = uint8(b >> 8)
+ s[3] = uint8(a >> 8)
+}
+
+func (p *NRGBA) SetNRGBA(x, y int, c color.NRGBA) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ s := p.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857
+ s[0] = c.R
+ s[1] = c.G
+ s[2] = c.B
+ s[3] = c.A
+}
+
+// SubImage returns an image representing the portion of the image p visible
+// through r. The returned value shares pixels with the original image.
+func (p *NRGBA) SubImage(r Rectangle) Image {
+ r = r.Intersect(p.Rect)
+ // If r1 and r2 are Rectangles, r1.Intersect(r2) is not guaranteed to be inside
+ // either r1 or r2 if the intersection is empty. Without explicitly checking for
+ // this, the Pix[i:] expression below can panic.
+ if r.Empty() {
+ return &NRGBA{}
+ }
+ i := p.PixOffset(r.Min.X, r.Min.Y)
+ return &NRGBA{
+ Pix: p.Pix[i:],
+ Stride: p.Stride,
+ Rect: r,
+ }
+}
+
+// Opaque scans the entire image and reports whether it is fully opaque.
+func (p *NRGBA) Opaque() bool {
+ if p.Rect.Empty() {
+ return true
+ }
+ i0, i1 := 3, p.Rect.Dx()*4
+ for y := p.Rect.Min.Y; y < p.Rect.Max.Y; y++ {
+ for i := i0; i < i1; i += 4 {
+ if p.Pix[i] != 0xff {
+ return false
+ }
+ }
+ i0 += p.Stride
+ i1 += p.Stride
+ }
+ return true
+}
+
+// NewNRGBA returns a new [NRGBA] image with the given bounds.
+func NewNRGBA(r Rectangle) *NRGBA {
+ return &NRGBA{
+ Pix: make([]uint8, pixelBufferLength(4, r, "NRGBA")),
+ Stride: 4 * r.Dx(),
+ Rect: r,
+ }
+}
+
+// NRGBA64 is an in-memory image whose At method returns [color.NRGBA64] values.
+type NRGBA64 struct {
+ // Pix holds the image's pixels, in R, G, B, A order and big-endian format. The pixel at
+ // (x, y) starts at Pix[(y-Rect.Min.Y)*Stride + (x-Rect.Min.X)*8].
+ Pix []uint8
+ // Stride is the Pix stride (in bytes) between vertically adjacent pixels.
+ Stride int
+ // Rect is the image's bounds.
+ Rect Rectangle
+}
+
+func (p *NRGBA64) ColorModel() color.Model { return color.NRGBA64Model }
+
+func (p *NRGBA64) Bounds() Rectangle { return p.Rect }
+
+func (p *NRGBA64) At(x, y int) color.Color {
+ return p.NRGBA64At(x, y)
+}
+
+func (p *NRGBA64) RGBA64At(x, y int) color.RGBA64 {
+ r, g, b, a := p.NRGBA64At(x, y).RGBA()
+ return color.RGBA64{uint16(r), uint16(g), uint16(b), uint16(a)}
+}
+
+func (p *NRGBA64) NRGBA64At(x, y int) color.NRGBA64 {
+ if !(Point{x, y}.In(p.Rect)) {
+ return color.NRGBA64{}
+ }
+ i := p.PixOffset(x, y)
+ s := p.Pix[i : i+8 : i+8] // Small cap improves performance, see https://golang.org/issue/27857
+ return color.NRGBA64{
+ uint16(s[0])<<8 | uint16(s[1]),
+ uint16(s[2])<<8 | uint16(s[3]),
+ uint16(s[4])<<8 | uint16(s[5]),
+ uint16(s[6])<<8 | uint16(s[7]),
+ }
+}
+
+// PixOffset returns the index of the first element of Pix that corresponds to
+// the pixel at (x, y).
+func (p *NRGBA64) PixOffset(x, y int) int {
+ return (y-p.Rect.Min.Y)*p.Stride + (x-p.Rect.Min.X)*8
+}
+
+func (p *NRGBA64) Set(x, y int, c color.Color) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ c1 := color.NRGBA64Model.Convert(c).(color.NRGBA64)
+ s := p.Pix[i : i+8 : i+8] // Small cap improves performance, see https://golang.org/issue/27857
+ s[0] = uint8(c1.R >> 8)
+ s[1] = uint8(c1.R)
+ s[2] = uint8(c1.G >> 8)
+ s[3] = uint8(c1.G)
+ s[4] = uint8(c1.B >> 8)
+ s[5] = uint8(c1.B)
+ s[6] = uint8(c1.A >> 8)
+ s[7] = uint8(c1.A)
+}
+
+func (p *NRGBA64) SetRGBA64(x, y int, c color.RGBA64) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ r, g, b, a := uint32(c.R), uint32(c.G), uint32(c.B), uint32(c.A)
+ if (a != 0) && (a != 0xffff) {
+ r = (r * 0xffff) / a
+ g = (g * 0xffff) / a
+ b = (b * 0xffff) / a
+ }
+ i := p.PixOffset(x, y)
+ s := p.Pix[i : i+8 : i+8] // Small cap improves performance, see https://golang.org/issue/27857
+ s[0] = uint8(r >> 8)
+ s[1] = uint8(r)
+ s[2] = uint8(g >> 8)
+ s[3] = uint8(g)
+ s[4] = uint8(b >> 8)
+ s[5] = uint8(b)
+ s[6] = uint8(a >> 8)
+ s[7] = uint8(a)
+}
+
+func (p *NRGBA64) SetNRGBA64(x, y int, c color.NRGBA64) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ s := p.Pix[i : i+8 : i+8] // Small cap improves performance, see https://golang.org/issue/27857
+ s[0] = uint8(c.R >> 8)
+ s[1] = uint8(c.R)
+ s[2] = uint8(c.G >> 8)
+ s[3] = uint8(c.G)
+ s[4] = uint8(c.B >> 8)
+ s[5] = uint8(c.B)
+ s[6] = uint8(c.A >> 8)
+ s[7] = uint8(c.A)
+}
+
+// SubImage returns an image representing the portion of the image p visible
+// through r. The returned value shares pixels with the original image.
+func (p *NRGBA64) SubImage(r Rectangle) Image {
+ r = r.Intersect(p.Rect)
+ // If r1 and r2 are Rectangles, r1.Intersect(r2) is not guaranteed to be inside
+ // either r1 or r2 if the intersection is empty. Without explicitly checking for
+ // this, the Pix[i:] expression below can panic.
+ if r.Empty() {
+ return &NRGBA64{}
+ }
+ i := p.PixOffset(r.Min.X, r.Min.Y)
+ return &NRGBA64{
+ Pix: p.Pix[i:],
+ Stride: p.Stride,
+ Rect: r,
+ }
+}
+
+// Opaque scans the entire image and reports whether it is fully opaque.
+func (p *NRGBA64) Opaque() bool {
+ if p.Rect.Empty() {
+ return true
+ }
+ i0, i1 := 6, p.Rect.Dx()*8
+ for y := p.Rect.Min.Y; y < p.Rect.Max.Y; y++ {
+ for i := i0; i < i1; i += 8 {
+ if p.Pix[i+0] != 0xff || p.Pix[i+1] != 0xff {
+ return false
+ }
+ }
+ i0 += p.Stride
+ i1 += p.Stride
+ }
+ return true
+}
+
+// NewNRGBA64 returns a new [NRGBA64] image with the given bounds.
+func NewNRGBA64(r Rectangle) *NRGBA64 {
+ return &NRGBA64{
+ Pix: make([]uint8, pixelBufferLength(8, r, "NRGBA64")),
+ Stride: 8 * r.Dx(),
+ Rect: r,
+ }
+}
+
+// Alpha is an in-memory image whose At method returns [color.Alpha] values.
+type Alpha struct {
+ // Pix holds the image's pixels, as alpha values. The pixel at
+ // (x, y) starts at Pix[(y-Rect.Min.Y)*Stride + (x-Rect.Min.X)*1].
+ Pix []uint8
+ // Stride is the Pix stride (in bytes) between vertically adjacent pixels.
+ Stride int
+ // Rect is the image's bounds.
+ Rect Rectangle
+}
+
+func (p *Alpha) ColorModel() color.Model { return color.AlphaModel }
+
+func (p *Alpha) Bounds() Rectangle { return p.Rect }
+
+func (p *Alpha) At(x, y int) color.Color {
+ return p.AlphaAt(x, y)
+}
+
+func (p *Alpha) RGBA64At(x, y int) color.RGBA64 {
+ a := uint16(p.AlphaAt(x, y).A)
+ a |= a << 8
+ return color.RGBA64{a, a, a, a}
+}
+
+func (p *Alpha) AlphaAt(x, y int) color.Alpha {
+ if !(Point{x, y}.In(p.Rect)) {
+ return color.Alpha{}
+ }
+ i := p.PixOffset(x, y)
+ return color.Alpha{p.Pix[i]}
+}
+
+// PixOffset returns the index of the first element of Pix that corresponds to
+// the pixel at (x, y).
+func (p *Alpha) PixOffset(x, y int) int {
+ return (y-p.Rect.Min.Y)*p.Stride + (x-p.Rect.Min.X)*1
+}
+
+func (p *Alpha) Set(x, y int, c color.Color) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ p.Pix[i] = color.AlphaModel.Convert(c).(color.Alpha).A
+}
+
+func (p *Alpha) SetRGBA64(x, y int, c color.RGBA64) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ p.Pix[i] = uint8(c.A >> 8)
+}
+
+func (p *Alpha) SetAlpha(x, y int, c color.Alpha) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ p.Pix[i] = c.A
+}
+
+// SubImage returns an image representing the portion of the image p visible
+// through r. The returned value shares pixels with the original image.
+func (p *Alpha) SubImage(r Rectangle) Image {
+ r = r.Intersect(p.Rect)
+ // If r1 and r2 are Rectangles, r1.Intersect(r2) is not guaranteed to be inside
+ // either r1 or r2 if the intersection is empty. Without explicitly checking for
+ // this, the Pix[i:] expression below can panic.
+ if r.Empty() {
+ return &Alpha{}
+ }
+ i := p.PixOffset(r.Min.X, r.Min.Y)
+ return &Alpha{
+ Pix: p.Pix[i:],
+ Stride: p.Stride,
+ Rect: r,
+ }
+}
+
+// Opaque scans the entire image and reports whether it is fully opaque.
+func (p *Alpha) Opaque() bool {
+ if p.Rect.Empty() {
+ return true
+ }
+ i0, i1 := 0, p.Rect.Dx()
+ for y := p.Rect.Min.Y; y < p.Rect.Max.Y; y++ {
+ for i := i0; i < i1; i++ {
+ if p.Pix[i] != 0xff {
+ return false
+ }
+ }
+ i0 += p.Stride
+ i1 += p.Stride
+ }
+ return true
+}
+
+// NewAlpha returns a new [Alpha] image with the given bounds.
+func NewAlpha(r Rectangle) *Alpha {
+ return &Alpha{
+ Pix: make([]uint8, pixelBufferLength(1, r, "Alpha")),
+ Stride: 1 * r.Dx(),
+ Rect: r,
+ }
+}
+
+// Alpha16 is an in-memory image whose At method returns [color.Alpha16] values.
+type Alpha16 struct {
+ // Pix holds the image's pixels, as alpha values in big-endian format. The pixel at
+ // (x, y) starts at Pix[(y-Rect.Min.Y)*Stride + (x-Rect.Min.X)*2].
+ Pix []uint8
+ // Stride is the Pix stride (in bytes) between vertically adjacent pixels.
+ Stride int
+ // Rect is the image's bounds.
+ Rect Rectangle
+}
+
+func (p *Alpha16) ColorModel() color.Model { return color.Alpha16Model }
+
+func (p *Alpha16) Bounds() Rectangle { return p.Rect }
+
+func (p *Alpha16) At(x, y int) color.Color {
+ return p.Alpha16At(x, y)
+}
+
+func (p *Alpha16) RGBA64At(x, y int) color.RGBA64 {
+ a := p.Alpha16At(x, y).A
+ return color.RGBA64{a, a, a, a}
+}
+
+func (p *Alpha16) Alpha16At(x, y int) color.Alpha16 {
+ if !(Point{x, y}.In(p.Rect)) {
+ return color.Alpha16{}
+ }
+ i := p.PixOffset(x, y)
+ return color.Alpha16{uint16(p.Pix[i+0])<<8 | uint16(p.Pix[i+1])}
+}
+
+// PixOffset returns the index of the first element of Pix that corresponds to
+// the pixel at (x, y).
+func (p *Alpha16) PixOffset(x, y int) int {
+ return (y-p.Rect.Min.Y)*p.Stride + (x-p.Rect.Min.X)*2
+}
+
+func (p *Alpha16) Set(x, y int, c color.Color) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ c1 := color.Alpha16Model.Convert(c).(color.Alpha16)
+ p.Pix[i+0] = uint8(c1.A >> 8)
+ p.Pix[i+1] = uint8(c1.A)
+}
+
+func (p *Alpha16) SetRGBA64(x, y int, c color.RGBA64) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ p.Pix[i+0] = uint8(c.A >> 8)
+ p.Pix[i+1] = uint8(c.A)
+}
+
+func (p *Alpha16) SetAlpha16(x, y int, c color.Alpha16) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ p.Pix[i+0] = uint8(c.A >> 8)
+ p.Pix[i+1] = uint8(c.A)
+}
+
+// SubImage returns an image representing the portion of the image p visible
+// through r. The returned value shares pixels with the original image.
+func (p *Alpha16) SubImage(r Rectangle) Image {
+ r = r.Intersect(p.Rect)
+ // If r1 and r2 are Rectangles, r1.Intersect(r2) is not guaranteed to be inside
+ // either r1 or r2 if the intersection is empty. Without explicitly checking for
+ // this, the Pix[i:] expression below can panic.
+ if r.Empty() {
+ return &Alpha16{}
+ }
+ i := p.PixOffset(r.Min.X, r.Min.Y)
+ return &Alpha16{
+ Pix: p.Pix[i:],
+ Stride: p.Stride,
+ Rect: r,
+ }
+}
+
+// Opaque scans the entire image and reports whether it is fully opaque.
+func (p *Alpha16) Opaque() bool {
+ if p.Rect.Empty() {
+ return true
+ }
+ i0, i1 := 0, p.Rect.Dx()*2
+ for y := p.Rect.Min.Y; y < p.Rect.Max.Y; y++ {
+ for i := i0; i < i1; i += 2 {
+ if p.Pix[i+0] != 0xff || p.Pix[i+1] != 0xff {
+ return false
+ }
+ }
+ i0 += p.Stride
+ i1 += p.Stride
+ }
+ return true
+}
+
+// NewAlpha16 returns a new [Alpha16] image with the given bounds.
+func NewAlpha16(r Rectangle) *Alpha16 {
+ return &Alpha16{
+ Pix: make([]uint8, pixelBufferLength(2, r, "Alpha16")),
+ Stride: 2 * r.Dx(),
+ Rect: r,
+ }
+}
+
+// Gray is an in-memory image whose At method returns [color.Gray] values.
+type Gray struct {
+ // Pix holds the image's pixels, as gray values. The pixel at
+ // (x, y) starts at Pix[(y-Rect.Min.Y)*Stride + (x-Rect.Min.X)*1].
+ Pix []uint8
+ // Stride is the Pix stride (in bytes) between vertically adjacent pixels.
+ Stride int
+ // Rect is the image's bounds.
+ Rect Rectangle
+}
+
+func (p *Gray) ColorModel() color.Model { return color.GrayModel }
+
+func (p *Gray) Bounds() Rectangle { return p.Rect }
+
+func (p *Gray) At(x, y int) color.Color {
+ return p.GrayAt(x, y)
+}
+
+func (p *Gray) RGBA64At(x, y int) color.RGBA64 {
+ gray := uint16(p.GrayAt(x, y).Y)
+ gray |= gray << 8
+ return color.RGBA64{gray, gray, gray, 0xffff}
+}
+
+func (p *Gray) GrayAt(x, y int) color.Gray {
+ if !(Point{x, y}.In(p.Rect)) {
+ return color.Gray{}
+ }
+ i := p.PixOffset(x, y)
+ return color.Gray{p.Pix[i]}
+}
+
+// PixOffset returns the index of the first element of Pix that corresponds to
+// the pixel at (x, y).
+func (p *Gray) PixOffset(x, y int) int {
+ return (y-p.Rect.Min.Y)*p.Stride + (x-p.Rect.Min.X)*1
+}
+
+func (p *Gray) Set(x, y int, c color.Color) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ p.Pix[i] = color.GrayModel.Convert(c).(color.Gray).Y
+}
+
+func (p *Gray) SetRGBA64(x, y int, c color.RGBA64) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ // This formula is the same as in color.grayModel.
+ gray := (19595*uint32(c.R) + 38470*uint32(c.G) + 7471*uint32(c.B) + 1<<15) >> 24
+ i := p.PixOffset(x, y)
+ p.Pix[i] = uint8(gray)
+}
+
+func (p *Gray) SetGray(x, y int, c color.Gray) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ p.Pix[i] = c.Y
+}
+
+// SubImage returns an image representing the portion of the image p visible
+// through r. The returned value shares pixels with the original image.
+func (p *Gray) SubImage(r Rectangle) Image {
+ r = r.Intersect(p.Rect)
+ // If r1 and r2 are Rectangles, r1.Intersect(r2) is not guaranteed to be inside
+ // either r1 or r2 if the intersection is empty. Without explicitly checking for
+ // this, the Pix[i:] expression below can panic.
+ if r.Empty() {
+ return &Gray{}
+ }
+ i := p.PixOffset(r.Min.X, r.Min.Y)
+ return &Gray{
+ Pix: p.Pix[i:],
+ Stride: p.Stride,
+ Rect: r,
+ }
+}
+
+// Opaque scans the entire image and reports whether it is fully opaque.
+func (p *Gray) Opaque() bool {
+ return true
+}
+
+// NewGray returns a new [Gray] image with the given bounds.
+func NewGray(r Rectangle) *Gray {
+ return &Gray{
+ Pix: make([]uint8, pixelBufferLength(1, r, "Gray")),
+ Stride: 1 * r.Dx(),
+ Rect: r,
+ }
+}
+
+// Gray16 is an in-memory image whose At method returns [color.Gray16] values.
+type Gray16 struct {
+ // Pix holds the image's pixels, as gray values in big-endian format. The pixel at
+ // (x, y) starts at Pix[(y-Rect.Min.Y)*Stride + (x-Rect.Min.X)*2].
+ Pix []uint8
+ // Stride is the Pix stride (in bytes) between vertically adjacent pixels.
+ Stride int
+ // Rect is the image's bounds.
+ Rect Rectangle
+}
+
+func (p *Gray16) ColorModel() color.Model { return color.Gray16Model }
+
+func (p *Gray16) Bounds() Rectangle { return p.Rect }
+
+func (p *Gray16) At(x, y int) color.Color {
+ return p.Gray16At(x, y)
+}
+
+func (p *Gray16) RGBA64At(x, y int) color.RGBA64 {
+ gray := p.Gray16At(x, y).Y
+ return color.RGBA64{gray, gray, gray, 0xffff}
+}
+
+func (p *Gray16) Gray16At(x, y int) color.Gray16 {
+ if !(Point{x, y}.In(p.Rect)) {
+ return color.Gray16{}
+ }
+ i := p.PixOffset(x, y)
+ return color.Gray16{uint16(p.Pix[i+0])<<8 | uint16(p.Pix[i+1])}
+}
+
+// PixOffset returns the index of the first element of Pix that corresponds to
+// the pixel at (x, y).
+func (p *Gray16) PixOffset(x, y int) int {
+ return (y-p.Rect.Min.Y)*p.Stride + (x-p.Rect.Min.X)*2
+}
+
+func (p *Gray16) Set(x, y int, c color.Color) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ c1 := color.Gray16Model.Convert(c).(color.Gray16)
+ p.Pix[i+0] = uint8(c1.Y >> 8)
+ p.Pix[i+1] = uint8(c1.Y)
+}
+
+func (p *Gray16) SetRGBA64(x, y int, c color.RGBA64) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ // This formula is the same as in color.gray16Model.
+ gray := (19595*uint32(c.R) + 38470*uint32(c.G) + 7471*uint32(c.B) + 1<<15) >> 16
+ i := p.PixOffset(x, y)
+ p.Pix[i+0] = uint8(gray >> 8)
+ p.Pix[i+1] = uint8(gray)
+}
+
+func (p *Gray16) SetGray16(x, y int, c color.Gray16) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ p.Pix[i+0] = uint8(c.Y >> 8)
+ p.Pix[i+1] = uint8(c.Y)
+}
+
+// SubImage returns an image representing the portion of the image p visible
+// through r. The returned value shares pixels with the original image.
+func (p *Gray16) SubImage(r Rectangle) Image {
+ r = r.Intersect(p.Rect)
+ // If r1 and r2 are Rectangles, r1.Intersect(r2) is not guaranteed to be inside
+ // either r1 or r2 if the intersection is empty. Without explicitly checking for
+ // this, the Pix[i:] expression below can panic.
+ if r.Empty() {
+ return &Gray16{}
+ }
+ i := p.PixOffset(r.Min.X, r.Min.Y)
+ return &Gray16{
+ Pix: p.Pix[i:],
+ Stride: p.Stride,
+ Rect: r,
+ }
+}
+
+// Opaque scans the entire image and reports whether it is fully opaque.
+func (p *Gray16) Opaque() bool {
+ return true
+}
+
+// NewGray16 returns a new [Gray16] image with the given bounds.
+func NewGray16(r Rectangle) *Gray16 {
+ return &Gray16{
+ Pix: make([]uint8, pixelBufferLength(2, r, "Gray16")),
+ Stride: 2 * r.Dx(),
+ Rect: r,
+ }
+}
+
+// CMYK is an in-memory image whose At method returns [color.CMYK] values.
+type CMYK struct {
+ // Pix holds the image's pixels, in C, M, Y, K order. The pixel at
+ // (x, y) starts at Pix[(y-Rect.Min.Y)*Stride + (x-Rect.Min.X)*4].
+ Pix []uint8
+ // Stride is the Pix stride (in bytes) between vertically adjacent pixels.
+ Stride int
+ // Rect is the image's bounds.
+ Rect Rectangle
+}
+
+func (p *CMYK) ColorModel() color.Model { return color.CMYKModel }
+
+func (p *CMYK) Bounds() Rectangle { return p.Rect }
+
+func (p *CMYK) At(x, y int) color.Color {
+ return p.CMYKAt(x, y)
+}
+
+func (p *CMYK) RGBA64At(x, y int) color.RGBA64 {
+ r, g, b, a := p.CMYKAt(x, y).RGBA()
+ return color.RGBA64{uint16(r), uint16(g), uint16(b), uint16(a)}
+}
+
+func (p *CMYK) CMYKAt(x, y int) color.CMYK {
+ if !(Point{x, y}.In(p.Rect)) {
+ return color.CMYK{}
+ }
+ i := p.PixOffset(x, y)
+ s := p.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857
+ return color.CMYK{s[0], s[1], s[2], s[3]}
+}
+
+// PixOffset returns the index of the first element of Pix that corresponds to
+// the pixel at (x, y).
+func (p *CMYK) PixOffset(x, y int) int {
+ return (y-p.Rect.Min.Y)*p.Stride + (x-p.Rect.Min.X)*4
+}
+
+func (p *CMYK) Set(x, y int, c color.Color) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ c1 := color.CMYKModel.Convert(c).(color.CMYK)
+ s := p.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857
+ s[0] = c1.C
+ s[1] = c1.M
+ s[2] = c1.Y
+ s[3] = c1.K
+}
+
+func (p *CMYK) SetRGBA64(x, y int, c color.RGBA64) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ cc, mm, yy, kk := color.RGBToCMYK(uint8(c.R>>8), uint8(c.G>>8), uint8(c.B>>8))
+ i := p.PixOffset(x, y)
+ s := p.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857
+ s[0] = cc
+ s[1] = mm
+ s[2] = yy
+ s[3] = kk
+}
+
+func (p *CMYK) SetCMYK(x, y int, c color.CMYK) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ s := p.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857
+ s[0] = c.C
+ s[1] = c.M
+ s[2] = c.Y
+ s[3] = c.K
+}
+
+// SubImage returns an image representing the portion of the image p visible
+// through r. The returned value shares pixels with the original image.
+func (p *CMYK) SubImage(r Rectangle) Image {
+ r = r.Intersect(p.Rect)
+ // If r1 and r2 are Rectangles, r1.Intersect(r2) is not guaranteed to be inside
+ // either r1 or r2 if the intersection is empty. Without explicitly checking for
+ // this, the Pix[i:] expression below can panic.
+ if r.Empty() {
+ return &CMYK{}
+ }
+ i := p.PixOffset(r.Min.X, r.Min.Y)
+ return &CMYK{
+ Pix: p.Pix[i:],
+ Stride: p.Stride,
+ Rect: r,
+ }
+}
+
+// Opaque scans the entire image and reports whether it is fully opaque.
+func (p *CMYK) Opaque() bool {
+ return true
+}
+
+// NewCMYK returns a new CMYK image with the given bounds.
+func NewCMYK(r Rectangle) *CMYK {
+ return &CMYK{
+ Pix: make([]uint8, pixelBufferLength(4, r, "CMYK")),
+ Stride: 4 * r.Dx(),
+ Rect: r,
+ }
+}
+
+// Paletted is an in-memory image of uint8 indices into a given palette.
+type Paletted struct {
+ // Pix holds the image's pixels, as palette indices. The pixel at
+ // (x, y) starts at Pix[(y-Rect.Min.Y)*Stride + (x-Rect.Min.X)*1].
+ Pix []uint8
+ // Stride is the Pix stride (in bytes) between vertically adjacent pixels.
+ Stride int
+ // Rect is the image's bounds.
+ Rect Rectangle
+ // Palette is the image's palette.
+ Palette color.Palette
+}
+
+func (p *Paletted) ColorModel() color.Model { return p.Palette }
+
+func (p *Paletted) Bounds() Rectangle { return p.Rect }
+
+func (p *Paletted) At(x, y int) color.Color {
+ if len(p.Palette) == 0 {
+ return nil
+ }
+ if !(Point{x, y}.In(p.Rect)) {
+ return p.Palette[0]
+ }
+ i := p.PixOffset(x, y)
+ return p.Palette[p.Pix[i]]
+}
+
+func (p *Paletted) RGBA64At(x, y int) color.RGBA64 {
+ if len(p.Palette) == 0 {
+ return color.RGBA64{}
+ }
+ c := color.Color(nil)
+ if !(Point{x, y}.In(p.Rect)) {
+ c = p.Palette[0]
+ } else {
+ i := p.PixOffset(x, y)
+ c = p.Palette[p.Pix[i]]
+ }
+ r, g, b, a := c.RGBA()
+ return color.RGBA64{
+ uint16(r),
+ uint16(g),
+ uint16(b),
+ uint16(a),
+ }
+}
+
+// PixOffset returns the index of the first element of Pix that corresponds to
+// the pixel at (x, y).
+func (p *Paletted) PixOffset(x, y int) int {
+ return (y-p.Rect.Min.Y)*p.Stride + (x-p.Rect.Min.X)*1
+}
+
+func (p *Paletted) Set(x, y int, c color.Color) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ p.Pix[i] = uint8(p.Palette.Index(c))
+}
+
+func (p *Paletted) SetRGBA64(x, y int, c color.RGBA64) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ p.Pix[i] = uint8(p.Palette.Index(c))
+}
+
+func (p *Paletted) ColorIndexAt(x, y int) uint8 {
+ if !(Point{x, y}.In(p.Rect)) {
+ return 0
+ }
+ i := p.PixOffset(x, y)
+ return p.Pix[i]
+}
+
+func (p *Paletted) SetColorIndex(x, y int, index uint8) {
+ if !(Point{x, y}.In(p.Rect)) {
+ return
+ }
+ i := p.PixOffset(x, y)
+ p.Pix[i] = index
+}
+
+// SubImage returns an image representing the portion of the image p visible
+// through r. The returned value shares pixels with the original image.
+func (p *Paletted) SubImage(r Rectangle) Image {
+ r = r.Intersect(p.Rect)
+ // If r1 and r2 are Rectangles, r1.Intersect(r2) is not guaranteed to be inside
+ // either r1 or r2 if the intersection is empty. Without explicitly checking for
+ // this, the Pix[i:] expression below can panic.
+ if r.Empty() {
+ return &Paletted{
+ Palette: p.Palette,
+ }
+ }
+ i := p.PixOffset(r.Min.X, r.Min.Y)
+ return &Paletted{
+ Pix: p.Pix[i:],
+ Stride: p.Stride,
+ Rect: p.Rect.Intersect(r),
+ Palette: p.Palette,
+ }
+}
+
+// Opaque scans the entire image and reports whether it is fully opaque.
+func (p *Paletted) Opaque() bool {
+ var present [256]bool
+ i0, i1 := 0, p.Rect.Dx()
+ for y := p.Rect.Min.Y; y < p.Rect.Max.Y; y++ {
+ for _, c := range p.Pix[i0:i1] {
+ present[c] = true
+ }
+ i0 += p.Stride
+ i1 += p.Stride
+ }
+ for i, c := range p.Palette {
+ if !present[i] {
+ continue
+ }
+ _, _, _, a := c.RGBA()
+ if a != 0xffff {
+ return false
+ }
+ }
+ return true
+}
+
+// NewPaletted returns a new [Paletted] image with the given width, height and
+// palette.
+func NewPaletted(r Rectangle, p color.Palette) *Paletted {
+ return &Paletted{
+ Pix: make([]uint8, pixelBufferLength(1, r, "Paletted")),
+ Stride: 1 * r.Dx(),
+ Rect: r,
+ Palette: p,
+ }
+}
diff --git a/go/src/image/image_test.go b/go/src/image/image_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..7f41bcb6c7086f1eb737fdd33cac1cd8135c488a
--- /dev/null
+++ b/go/src/image/image_test.go
@@ -0,0 +1,458 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package image
+
+import (
+ "image/color"
+ "image/color/palette"
+ "testing"
+)
+
+type image interface {
+ Image
+ Opaque() bool
+ Set(int, int, color.Color)
+ SubImage(Rectangle) Image
+}
+
+func cmp(cm color.Model, c0, c1 color.Color) bool {
+ r0, g0, b0, a0 := cm.Convert(c0).RGBA()
+ r1, g1, b1, a1 := cm.Convert(c1).RGBA()
+ return r0 == r1 && g0 == g1 && b0 == b1 && a0 == a1
+}
+
+var testImages = []struct {
+ name string
+ image func() image
+}{
+ {"rgba", func() image { return NewRGBA(Rect(0, 0, 10, 10)) }},
+ {"rgba64", func() image { return NewRGBA64(Rect(0, 0, 10, 10)) }},
+ {"nrgba", func() image { return NewNRGBA(Rect(0, 0, 10, 10)) }},
+ {"nrgba64", func() image { return NewNRGBA64(Rect(0, 0, 10, 10)) }},
+ {"alpha", func() image { return NewAlpha(Rect(0, 0, 10, 10)) }},
+ {"alpha16", func() image { return NewAlpha16(Rect(0, 0, 10, 10)) }},
+ {"gray", func() image { return NewGray(Rect(0, 0, 10, 10)) }},
+ {"gray16", func() image { return NewGray16(Rect(0, 0, 10, 10)) }},
+ {"paletted", func() image {
+ return NewPaletted(Rect(0, 0, 10, 10), color.Palette{
+ Transparent,
+ Opaque,
+ })
+ }},
+}
+
+func TestImage(t *testing.T) {
+ for _, tc := range testImages {
+ m := tc.image()
+ if !Rect(0, 0, 10, 10).Eq(m.Bounds()) {
+ t.Errorf("%T: want bounds %v, got %v", m, Rect(0, 0, 10, 10), m.Bounds())
+ continue
+ }
+ if !cmp(m.ColorModel(), Transparent, m.At(6, 3)) {
+ t.Errorf("%T: at (6, 3), want a zero color, got %v", m, m.At(6, 3))
+ continue
+ }
+ m.Set(6, 3, Opaque)
+ if !cmp(m.ColorModel(), Opaque, m.At(6, 3)) {
+ t.Errorf("%T: at (6, 3), want a non-zero color, got %v", m, m.At(6, 3))
+ continue
+ }
+ if !m.SubImage(Rect(6, 3, 7, 4)).(image).Opaque() {
+ t.Errorf("%T: at (6, 3) was not opaque", m)
+ continue
+ }
+ m = m.SubImage(Rect(3, 2, 9, 8)).(image)
+ if !Rect(3, 2, 9, 8).Eq(m.Bounds()) {
+ t.Errorf("%T: sub-image want bounds %v, got %v", m, Rect(3, 2, 9, 8), m.Bounds())
+ continue
+ }
+ if !cmp(m.ColorModel(), Opaque, m.At(6, 3)) {
+ t.Errorf("%T: sub-image at (6, 3), want a non-zero color, got %v", m, m.At(6, 3))
+ continue
+ }
+ if !cmp(m.ColorModel(), Transparent, m.At(3, 3)) {
+ t.Errorf("%T: sub-image at (3, 3), want a zero color, got %v", m, m.At(3, 3))
+ continue
+ }
+ m.Set(3, 3, Opaque)
+ if !cmp(m.ColorModel(), Opaque, m.At(3, 3)) {
+ t.Errorf("%T: sub-image at (3, 3), want a non-zero color, got %v", m, m.At(3, 3))
+ continue
+ }
+ // Test that taking an empty sub-image starting at a corner does not panic.
+ m.SubImage(Rect(0, 0, 0, 0))
+ m.SubImage(Rect(10, 0, 10, 0))
+ m.SubImage(Rect(0, 10, 0, 10))
+ m.SubImage(Rect(10, 10, 10, 10))
+ }
+}
+
+func TestNewXxxBadRectangle(t *testing.T) {
+ // call calls f(r) and reports whether it ran without panicking.
+ call := func(f func(Rectangle), r Rectangle) (ok bool) {
+ defer func() {
+ if recover() != nil {
+ ok = false
+ }
+ }()
+ f(r)
+ return true
+ }
+
+ testCases := []struct {
+ name string
+ f func(Rectangle)
+ }{
+ {"RGBA", func(r Rectangle) { NewRGBA(r) }},
+ {"RGBA64", func(r Rectangle) { NewRGBA64(r) }},
+ {"NRGBA", func(r Rectangle) { NewNRGBA(r) }},
+ {"NRGBA64", func(r Rectangle) { NewNRGBA64(r) }},
+ {"Alpha", func(r Rectangle) { NewAlpha(r) }},
+ {"Alpha16", func(r Rectangle) { NewAlpha16(r) }},
+ {"Gray", func(r Rectangle) { NewGray(r) }},
+ {"Gray16", func(r Rectangle) { NewGray16(r) }},
+ {"CMYK", func(r Rectangle) { NewCMYK(r) }},
+ {"Paletted", func(r Rectangle) { NewPaletted(r, color.Palette{color.Black, color.White}) }},
+ {"YCbCr", func(r Rectangle) { NewYCbCr(r, YCbCrSubsampleRatio422) }},
+ {"NYCbCrA", func(r Rectangle) { NewNYCbCrA(r, YCbCrSubsampleRatio444) }},
+ }
+
+ for _, tc := range testCases {
+ // Calling NewXxx(r) should fail (panic, since NewXxx doesn't return an
+ // error) unless r's width and height are both non-negative.
+ for _, negDx := range []bool{false, true} {
+ for _, negDy := range []bool{false, true} {
+ r := Rectangle{
+ Min: Point{15, 28},
+ Max: Point{16, 29},
+ }
+ if negDx {
+ r.Max.X = 14
+ }
+ if negDy {
+ r.Max.Y = 27
+ }
+
+ got := call(tc.f, r)
+ want := !negDx && !negDy
+ if got != want {
+ t.Errorf("New%s: negDx=%t, negDy=%t: got %t, want %t",
+ tc.name, negDx, negDy, got, want)
+ }
+ }
+ }
+
+ // Passing a Rectangle whose width and height is MaxInt should also fail
+ // (panic), due to overflow.
+ {
+ zeroAsUint := uint(0)
+ maxUint := zeroAsUint - 1
+ maxInt := int(maxUint / 2)
+ got := call(tc.f, Rectangle{
+ Min: Point{0, 0},
+ Max: Point{maxInt, maxInt},
+ })
+ if got {
+ t.Errorf("New%s: overflow: got ok, want !ok", tc.name)
+ }
+ }
+ }
+}
+
+func Test16BitsPerColorChannel(t *testing.T) {
+ testColorModel := []color.Model{
+ color.RGBA64Model,
+ color.NRGBA64Model,
+ color.Alpha16Model,
+ color.Gray16Model,
+ }
+ for _, cm := range testColorModel {
+ c := cm.Convert(color.RGBA64{0x1234, 0x1234, 0x1234, 0x1234}) // Premultiplied alpha.
+ r, _, _, _ := c.RGBA()
+ if r != 0x1234 {
+ t.Errorf("%T: want red value 0x%04x got 0x%04x", c, 0x1234, r)
+ continue
+ }
+ }
+ testImage := []image{
+ NewRGBA64(Rect(0, 0, 10, 10)),
+ NewNRGBA64(Rect(0, 0, 10, 10)),
+ NewAlpha16(Rect(0, 0, 10, 10)),
+ NewGray16(Rect(0, 0, 10, 10)),
+ }
+ for _, m := range testImage {
+ m.Set(1, 2, color.NRGBA64{0xffff, 0xffff, 0xffff, 0x1357}) // Non-premultiplied alpha.
+ r, _, _, _ := m.At(1, 2).RGBA()
+ if r != 0x1357 {
+ t.Errorf("%T: want red value 0x%04x got 0x%04x", m, 0x1357, r)
+ continue
+ }
+ }
+}
+
+func TestRGBA64Image(t *testing.T) {
+ // memset sets every element of s to v.
+ memset := func(s []byte, v byte) {
+ for i := range s {
+ s[i] = v
+ }
+ }
+
+ r := Rect(0, 0, 3, 2)
+ testCases := []Image{
+ NewAlpha(r),
+ NewAlpha16(r),
+ NewCMYK(r),
+ NewGray(r),
+ NewGray16(r),
+ NewNRGBA(r),
+ NewNRGBA64(r),
+ NewNYCbCrA(r, YCbCrSubsampleRatio444),
+ NewPaletted(r, palette.Plan9),
+ NewRGBA(r),
+ NewRGBA64(r),
+ NewUniform(color.RGBA64{}),
+ NewYCbCr(r, YCbCrSubsampleRatio444),
+ r,
+ }
+ for _, tc := range testCases {
+ switch tc := tc.(type) {
+ // Most of the concrete image types in the testCases implement the
+ // draw.RGBA64Image interface: they have a SetRGBA64 method. We use an
+ // interface literal here, instead of importing "image/draw", to avoid
+ // an import cycle.
+ //
+ // The YCbCr and NYCbCrA types are special-cased. Chroma subsampling
+ // means that setting one pixel can modify neighboring pixels. They
+ // don't have Set or SetRGBA64 methods because that side effect could
+ // be surprising. Here, we just memset the channel buffers instead.
+ //
+ // The Uniform and Rectangle types are also special-cased, as they
+ // don't have a Set or SetRGBA64 method.
+ case interface {
+ SetRGBA64(x, y int, c color.RGBA64)
+ }:
+ tc.SetRGBA64(1, 1, color.RGBA64{0x7FFF, 0x3FFF, 0x0000, 0x7FFF})
+
+ case *NYCbCrA:
+ memset(tc.YCbCr.Y, 0x77)
+ memset(tc.YCbCr.Cb, 0x88)
+ memset(tc.YCbCr.Cr, 0x99)
+ memset(tc.A, 0xAA)
+
+ case *Uniform:
+ tc.C = color.RGBA64{0x7FFF, 0x3FFF, 0x0000, 0x7FFF}
+
+ case *YCbCr:
+ memset(tc.Y, 0x77)
+ memset(tc.Cb, 0x88)
+ memset(tc.Cr, 0x99)
+
+ case Rectangle:
+ // No-op. Rectangle pixels' colors are immutable. They're always
+ // color.Opaque.
+
+ default:
+ t.Errorf("could not initialize pixels for %T", tc)
+ continue
+ }
+
+ // Check that RGBA64At(x, y) is equivalent to At(x, y).RGBA().
+ rgba64Image, ok := tc.(RGBA64Image)
+ if !ok {
+ t.Errorf("%T is not an RGBA64Image", tc)
+ continue
+ }
+ got := rgba64Image.RGBA64At(1, 1)
+ wantR, wantG, wantB, wantA := tc.At(1, 1).RGBA()
+ if (uint32(got.R) != wantR) || (uint32(got.G) != wantG) ||
+ (uint32(got.B) != wantB) || (uint32(got.A) != wantA) {
+ t.Errorf("%T:\ngot (0x%04X, 0x%04X, 0x%04X, 0x%04X)\n"+
+ "want (0x%04X, 0x%04X, 0x%04X, 0x%04X)", tc,
+ got.R, got.G, got.B, got.A,
+ wantR, wantG, wantB, wantA)
+ continue
+ }
+ }
+}
+
+func BenchmarkAt(b *testing.B) {
+ for _, tc := range testImages {
+ b.Run(tc.name, func(b *testing.B) {
+ m := tc.image()
+ b.ReportAllocs()
+ b.ResetTimer()
+ for i := 0; i < b.N; i++ {
+ m.At(4, 5)
+ }
+ })
+ }
+}
+
+func BenchmarkSet(b *testing.B) {
+ c := color.Gray{0xff}
+ for _, tc := range testImages {
+ b.Run(tc.name, func(b *testing.B) {
+ m := tc.image()
+ b.ReportAllocs()
+ b.ResetTimer()
+ for i := 0; i < b.N; i++ {
+ m.Set(4, 5, c)
+ }
+ })
+ }
+}
+
+func BenchmarkRGBAAt(b *testing.B) {
+ m := NewRGBA(Rect(0, 0, 10, 10))
+ b.ResetTimer()
+
+ for i := 0; i < b.N; i++ {
+ m.RGBAAt(4, 5)
+ }
+}
+
+func BenchmarkRGBASetRGBA(b *testing.B) {
+ m := NewRGBA(Rect(0, 0, 10, 10))
+ c := color.RGBA{0xff, 0xff, 0xff, 0x13}
+ b.ResetTimer()
+
+ for i := 0; i < b.N; i++ {
+ m.SetRGBA(4, 5, c)
+ }
+}
+
+func BenchmarkRGBA64At(b *testing.B) {
+ m := NewRGBA64(Rect(0, 0, 10, 10))
+ b.ResetTimer()
+
+ for i := 0; i < b.N; i++ {
+ m.RGBA64At(4, 5)
+ }
+}
+
+func BenchmarkRGBA64SetRGBA64(b *testing.B) {
+ m := NewRGBA64(Rect(0, 0, 10, 10))
+ c := color.RGBA64{0xffff, 0xffff, 0xffff, 0x1357}
+ b.ResetTimer()
+
+ for i := 0; i < b.N; i++ {
+ m.SetRGBA64(4, 5, c)
+ }
+}
+
+func BenchmarkNRGBAAt(b *testing.B) {
+ m := NewNRGBA(Rect(0, 0, 10, 10))
+ b.ResetTimer()
+
+ for i := 0; i < b.N; i++ {
+ m.NRGBAAt(4, 5)
+ }
+}
+
+func BenchmarkNRGBASetNRGBA(b *testing.B) {
+ m := NewNRGBA(Rect(0, 0, 10, 10))
+ c := color.NRGBA{0xff, 0xff, 0xff, 0x13}
+ b.ResetTimer()
+
+ for i := 0; i < b.N; i++ {
+ m.SetNRGBA(4, 5, c)
+ }
+}
+
+func BenchmarkNRGBA64At(b *testing.B) {
+ m := NewNRGBA64(Rect(0, 0, 10, 10))
+ b.ResetTimer()
+
+ for i := 0; i < b.N; i++ {
+ m.NRGBA64At(4, 5)
+ }
+}
+
+func BenchmarkNRGBA64SetNRGBA64(b *testing.B) {
+ m := NewNRGBA64(Rect(0, 0, 10, 10))
+ c := color.NRGBA64{0xffff, 0xffff, 0xffff, 0x1357}
+ b.ResetTimer()
+
+ for i := 0; i < b.N; i++ {
+ m.SetNRGBA64(4, 5, c)
+ }
+}
+
+func BenchmarkAlphaAt(b *testing.B) {
+ m := NewAlpha(Rect(0, 0, 10, 10))
+ b.ResetTimer()
+
+ for i := 0; i < b.N; i++ {
+ m.AlphaAt(4, 5)
+ }
+}
+
+func BenchmarkAlphaSetAlpha(b *testing.B) {
+ m := NewAlpha(Rect(0, 0, 10, 10))
+ c := color.Alpha{0x13}
+ b.ResetTimer()
+
+ for i := 0; i < b.N; i++ {
+ m.SetAlpha(4, 5, c)
+ }
+}
+
+func BenchmarkAlpha16At(b *testing.B) {
+ m := NewAlpha16(Rect(0, 0, 10, 10))
+ b.ResetTimer()
+
+ for i := 0; i < b.N; i++ {
+ m.Alpha16At(4, 5)
+ }
+}
+
+func BenchmarkAlphaSetAlpha16(b *testing.B) {
+ m := NewAlpha16(Rect(0, 0, 10, 10))
+ c := color.Alpha16{0x13}
+ b.ResetTimer()
+
+ for i := 0; i < b.N; i++ {
+ m.SetAlpha16(4, 5, c)
+ }
+}
+
+func BenchmarkGrayAt(b *testing.B) {
+ m := NewGray(Rect(0, 0, 10, 10))
+ b.ResetTimer()
+
+ for i := 0; i < b.N; i++ {
+ m.GrayAt(4, 5)
+ }
+}
+
+func BenchmarkGraySetGray(b *testing.B) {
+ m := NewGray(Rect(0, 0, 10, 10))
+ c := color.Gray{0x13}
+ b.ResetTimer()
+
+ for i := 0; i < b.N; i++ {
+ m.SetGray(4, 5, c)
+ }
+}
+
+func BenchmarkGray16At(b *testing.B) {
+ m := NewGray16(Rect(0, 0, 10, 10))
+ b.ResetTimer()
+
+ for i := 0; i < b.N; i++ {
+ m.Gray16At(4, 5)
+ }
+}
+
+func BenchmarkGraySetGray16(b *testing.B) {
+ m := NewGray16(Rect(0, 0, 10, 10))
+ c := color.Gray16{0x13}
+ b.ResetTimer()
+
+ for i := 0; i < b.N; i++ {
+ m.SetGray16(4, 5, c)
+ }
+}
diff --git a/go/src/image/names.go b/go/src/image/names.go
new file mode 100644
index 0000000000000000000000000000000000000000..a2968fabe27d275c60d336801deb1f6b26d2cd66
--- /dev/null
+++ b/go/src/image/names.go
@@ -0,0 +1,58 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package image
+
+import (
+ "image/color"
+)
+
+var (
+ // Black is an opaque black uniform image.
+ Black = NewUniform(color.Black)
+ // White is an opaque white uniform image.
+ White = NewUniform(color.White)
+ // Transparent is a fully transparent uniform image.
+ Transparent = NewUniform(color.Transparent)
+ // Opaque is a fully opaque uniform image.
+ Opaque = NewUniform(color.Opaque)
+)
+
+// Uniform is an infinite-sized [Image] of uniform color.
+// It implements the [color.Color], [color.Model], and [Image] interfaces.
+type Uniform struct {
+ C color.Color
+}
+
+func (c *Uniform) RGBA() (r, g, b, a uint32) {
+ return c.C.RGBA()
+}
+
+func (c *Uniform) ColorModel() color.Model {
+ return c
+}
+
+func (c *Uniform) Convert(color.Color) color.Color {
+ return c.C
+}
+
+func (c *Uniform) Bounds() Rectangle { return Rectangle{Point{-1e9, -1e9}, Point{1e9, 1e9}} }
+
+func (c *Uniform) At(x, y int) color.Color { return c.C }
+
+func (c *Uniform) RGBA64At(x, y int) color.RGBA64 {
+ r, g, b, a := c.C.RGBA()
+ return color.RGBA64{uint16(r), uint16(g), uint16(b), uint16(a)}
+}
+
+// Opaque scans the entire image and reports whether it is fully opaque.
+func (c *Uniform) Opaque() bool {
+ _, _, _, a := c.C.RGBA()
+ return a == 0xffff
+}
+
+// NewUniform returns a new [Uniform] image of the given color.
+func NewUniform(c color.Color) *Uniform {
+ return &Uniform{c}
+}
diff --git a/go/src/image/ycbcr.go b/go/src/image/ycbcr.go
new file mode 100644
index 0000000000000000000000000000000000000000..54333119431d0f756e80b8e9aaa2443fa6c62d97
--- /dev/null
+++ b/go/src/image/ycbcr.go
@@ -0,0 +1,329 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package image
+
+import (
+ "image/color"
+)
+
+// YCbCrSubsampleRatio is the chroma subsample ratio used in a YCbCr image.
+type YCbCrSubsampleRatio int
+
+const (
+ YCbCrSubsampleRatio444 YCbCrSubsampleRatio = iota
+ YCbCrSubsampleRatio422
+ YCbCrSubsampleRatio420
+ YCbCrSubsampleRatio440
+ YCbCrSubsampleRatio411
+ YCbCrSubsampleRatio410
+)
+
+func (s YCbCrSubsampleRatio) String() string {
+ switch s {
+ case YCbCrSubsampleRatio444:
+ return "YCbCrSubsampleRatio444"
+ case YCbCrSubsampleRatio422:
+ return "YCbCrSubsampleRatio422"
+ case YCbCrSubsampleRatio420:
+ return "YCbCrSubsampleRatio420"
+ case YCbCrSubsampleRatio440:
+ return "YCbCrSubsampleRatio440"
+ case YCbCrSubsampleRatio411:
+ return "YCbCrSubsampleRatio411"
+ case YCbCrSubsampleRatio410:
+ return "YCbCrSubsampleRatio410"
+ }
+ return "YCbCrSubsampleRatioUnknown"
+}
+
+// YCbCr is an in-memory image of Y'CbCr colors. There is one Y sample per
+// pixel, but each Cb and Cr sample can span one or more pixels.
+// YStride is the Y slice index delta between vertically adjacent pixels.
+// CStride is the Cb and Cr slice index delta between vertically adjacent pixels
+// that map to separate chroma samples.
+// It is not an absolute requirement, but YStride and len(Y) are typically
+// multiples of 8, and:
+//
+// For 4:4:4, CStride == YStride/1 && len(Cb) == len(Cr) == len(Y)/1.
+// For 4:2:2, CStride == YStride/2 && len(Cb) == len(Cr) == len(Y)/2.
+// For 4:2:0, CStride == YStride/2 && len(Cb) == len(Cr) == len(Y)/4.
+// For 4:4:0, CStride == YStride/1 && len(Cb) == len(Cr) == len(Y)/2.
+// For 4:1:1, CStride == YStride/4 && len(Cb) == len(Cr) == len(Y)/4.
+// For 4:1:0, CStride == YStride/4 && len(Cb) == len(Cr) == len(Y)/8.
+type YCbCr struct {
+ Y, Cb, Cr []uint8
+ YStride int
+ CStride int
+ SubsampleRatio YCbCrSubsampleRatio
+ Rect Rectangle
+}
+
+func (p *YCbCr) ColorModel() color.Model {
+ return color.YCbCrModel
+}
+
+func (p *YCbCr) Bounds() Rectangle {
+ return p.Rect
+}
+
+func (p *YCbCr) At(x, y int) color.Color {
+ return p.YCbCrAt(x, y)
+}
+
+func (p *YCbCr) RGBA64At(x, y int) color.RGBA64 {
+ r, g, b, a := p.YCbCrAt(x, y).RGBA()
+ return color.RGBA64{uint16(r), uint16(g), uint16(b), uint16(a)}
+}
+
+func (p *YCbCr) YCbCrAt(x, y int) color.YCbCr {
+ if !(Point{x, y}.In(p.Rect)) {
+ return color.YCbCr{}
+ }
+ yi := p.YOffset(x, y)
+ ci := p.COffset(x, y)
+ return color.YCbCr{
+ p.Y[yi],
+ p.Cb[ci],
+ p.Cr[ci],
+ }
+}
+
+// YOffset returns the index of the first element of Y that corresponds to
+// the pixel at (x, y).
+func (p *YCbCr) YOffset(x, y int) int {
+ return (y-p.Rect.Min.Y)*p.YStride + (x - p.Rect.Min.X)
+}
+
+// COffset returns the index of the first element of Cb or Cr that corresponds
+// to the pixel at (x, y).
+func (p *YCbCr) COffset(x, y int) int {
+ switch p.SubsampleRatio {
+ case YCbCrSubsampleRatio422:
+ return (y-p.Rect.Min.Y)*p.CStride + (x/2 - p.Rect.Min.X/2)
+ case YCbCrSubsampleRatio420:
+ return (y/2-p.Rect.Min.Y/2)*p.CStride + (x/2 - p.Rect.Min.X/2)
+ case YCbCrSubsampleRatio440:
+ return (y/2-p.Rect.Min.Y/2)*p.CStride + (x - p.Rect.Min.X)
+ case YCbCrSubsampleRatio411:
+ return (y-p.Rect.Min.Y)*p.CStride + (x/4 - p.Rect.Min.X/4)
+ case YCbCrSubsampleRatio410:
+ return (y/2-p.Rect.Min.Y/2)*p.CStride + (x/4 - p.Rect.Min.X/4)
+ }
+ // Default to 4:4:4 subsampling.
+ return (y-p.Rect.Min.Y)*p.CStride + (x - p.Rect.Min.X)
+}
+
+// SubImage returns an image representing the portion of the image p visible
+// through r. The returned value shares pixels with the original image.
+func (p *YCbCr) SubImage(r Rectangle) Image {
+ r = r.Intersect(p.Rect)
+ // If r1 and r2 are Rectangles, r1.Intersect(r2) is not guaranteed to be inside
+ // either r1 or r2 if the intersection is empty. Without explicitly checking for
+ // this, the Pix[i:] expression below can panic.
+ if r.Empty() {
+ return &YCbCr{
+ SubsampleRatio: p.SubsampleRatio,
+ }
+ }
+ yi := p.YOffset(r.Min.X, r.Min.Y)
+ ci := p.COffset(r.Min.X, r.Min.Y)
+ return &YCbCr{
+ Y: p.Y[yi:],
+ Cb: p.Cb[ci:],
+ Cr: p.Cr[ci:],
+ SubsampleRatio: p.SubsampleRatio,
+ YStride: p.YStride,
+ CStride: p.CStride,
+ Rect: r,
+ }
+}
+
+func (p *YCbCr) Opaque() bool {
+ return true
+}
+
+func yCbCrSize(r Rectangle, subsampleRatio YCbCrSubsampleRatio) (w, h, cw, ch int) {
+ w, h = r.Dx(), r.Dy()
+ switch subsampleRatio {
+ case YCbCrSubsampleRatio422:
+ cw = (r.Max.X+1)/2 - r.Min.X/2
+ ch = h
+ case YCbCrSubsampleRatio420:
+ cw = (r.Max.X+1)/2 - r.Min.X/2
+ ch = (r.Max.Y+1)/2 - r.Min.Y/2
+ case YCbCrSubsampleRatio440:
+ cw = w
+ ch = (r.Max.Y+1)/2 - r.Min.Y/2
+ case YCbCrSubsampleRatio411:
+ cw = (r.Max.X+3)/4 - r.Min.X/4
+ ch = h
+ case YCbCrSubsampleRatio410:
+ cw = (r.Max.X+3)/4 - r.Min.X/4
+ ch = (r.Max.Y+1)/2 - r.Min.Y/2
+ default:
+ // Default to 4:4:4 subsampling.
+ cw = w
+ ch = h
+ }
+ return
+}
+
+// NewYCbCr returns a new YCbCr image with the given bounds and subsample
+// ratio.
+func NewYCbCr(r Rectangle, subsampleRatio YCbCrSubsampleRatio) *YCbCr {
+ w, h, cw, ch := yCbCrSize(r, subsampleRatio)
+
+ // totalLength should be the same as i2, below, for a valid Rectangle r.
+ totalLength := add2NonNeg(
+ mul3NonNeg(1, w, h),
+ mul3NonNeg(2, cw, ch),
+ )
+ if totalLength < 0 {
+ panic("image: NewYCbCr Rectangle has huge or negative dimensions")
+ }
+
+ i0 := w*h + 0*cw*ch
+ i1 := w*h + 1*cw*ch
+ i2 := w*h + 2*cw*ch
+ b := make([]byte, i2)
+ return &YCbCr{
+ Y: b[:i0:i0],
+ Cb: b[i0:i1:i1],
+ Cr: b[i1:i2:i2],
+ SubsampleRatio: subsampleRatio,
+ YStride: w,
+ CStride: cw,
+ Rect: r,
+ }
+}
+
+// NYCbCrA is an in-memory image of non-alpha-premultiplied Y'CbCr-with-alpha
+// colors. A and AStride are analogous to the Y and YStride fields of the
+// embedded YCbCr.
+type NYCbCrA struct {
+ YCbCr
+ A []uint8
+ AStride int
+}
+
+func (p *NYCbCrA) ColorModel() color.Model {
+ return color.NYCbCrAModel
+}
+
+func (p *NYCbCrA) At(x, y int) color.Color {
+ return p.NYCbCrAAt(x, y)
+}
+
+func (p *NYCbCrA) RGBA64At(x, y int) color.RGBA64 {
+ r, g, b, a := p.NYCbCrAAt(x, y).RGBA()
+ return color.RGBA64{uint16(r), uint16(g), uint16(b), uint16(a)}
+}
+
+func (p *NYCbCrA) NYCbCrAAt(x, y int) color.NYCbCrA {
+ if !(Point{X: x, Y: y}.In(p.Rect)) {
+ return color.NYCbCrA{}
+ }
+ yi := p.YOffset(x, y)
+ ci := p.COffset(x, y)
+ ai := p.AOffset(x, y)
+ return color.NYCbCrA{
+ color.YCbCr{
+ Y: p.Y[yi],
+ Cb: p.Cb[ci],
+ Cr: p.Cr[ci],
+ },
+ p.A[ai],
+ }
+}
+
+// AOffset returns the index of the first element of A that corresponds to the
+// pixel at (x, y).
+func (p *NYCbCrA) AOffset(x, y int) int {
+ return (y-p.Rect.Min.Y)*p.AStride + (x - p.Rect.Min.X)
+}
+
+// SubImage returns an image representing the portion of the image p visible
+// through r. The returned value shares pixels with the original image.
+func (p *NYCbCrA) SubImage(r Rectangle) Image {
+ r = r.Intersect(p.Rect)
+ // If r1 and r2 are Rectangles, r1.Intersect(r2) is not guaranteed to be inside
+ // either r1 or r2 if the intersection is empty. Without explicitly checking for
+ // this, the Pix[i:] expression below can panic.
+ if r.Empty() {
+ return &NYCbCrA{
+ YCbCr: YCbCr{
+ SubsampleRatio: p.SubsampleRatio,
+ },
+ }
+ }
+ yi := p.YOffset(r.Min.X, r.Min.Y)
+ ci := p.COffset(r.Min.X, r.Min.Y)
+ ai := p.AOffset(r.Min.X, r.Min.Y)
+ return &NYCbCrA{
+ YCbCr: YCbCr{
+ Y: p.Y[yi:],
+ Cb: p.Cb[ci:],
+ Cr: p.Cr[ci:],
+ SubsampleRatio: p.SubsampleRatio,
+ YStride: p.YStride,
+ CStride: p.CStride,
+ Rect: r,
+ },
+ A: p.A[ai:],
+ AStride: p.AStride,
+ }
+}
+
+// Opaque scans the entire image and reports whether it is fully opaque.
+func (p *NYCbCrA) Opaque() bool {
+ if p.Rect.Empty() {
+ return true
+ }
+ i0, i1 := 0, p.Rect.Dx()
+ for y := p.Rect.Min.Y; y < p.Rect.Max.Y; y++ {
+ for _, a := range p.A[i0:i1] {
+ if a != 0xff {
+ return false
+ }
+ }
+ i0 += p.AStride
+ i1 += p.AStride
+ }
+ return true
+}
+
+// NewNYCbCrA returns a new [NYCbCrA] image with the given bounds and subsample
+// ratio.
+func NewNYCbCrA(r Rectangle, subsampleRatio YCbCrSubsampleRatio) *NYCbCrA {
+ w, h, cw, ch := yCbCrSize(r, subsampleRatio)
+
+ // totalLength should be the same as i3, below, for a valid Rectangle r.
+ totalLength := add2NonNeg(
+ mul3NonNeg(2, w, h),
+ mul3NonNeg(2, cw, ch),
+ )
+ if totalLength < 0 {
+ panic("image: NewNYCbCrA Rectangle has huge or negative dimension")
+ }
+
+ i0 := 1*w*h + 0*cw*ch
+ i1 := 1*w*h + 1*cw*ch
+ i2 := 1*w*h + 2*cw*ch
+ i3 := 2*w*h + 2*cw*ch
+ b := make([]byte, i3)
+ return &NYCbCrA{
+ YCbCr: YCbCr{
+ Y: b[:i0:i0],
+ Cb: b[i0:i1:i1],
+ Cr: b[i1:i2:i2],
+ SubsampleRatio: subsampleRatio,
+ YStride: w,
+ CStride: cw,
+ Rect: r,
+ },
+ A: b[i2:],
+ AStride: w,
+ }
+}
diff --git a/go/src/image/ycbcr_test.go b/go/src/image/ycbcr_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..4996bc8dcaeeb1d67b5adbdcbf58aa4723179c6e
--- /dev/null
+++ b/go/src/image/ycbcr_test.go
@@ -0,0 +1,133 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package image
+
+import (
+ "image/color"
+ "testing"
+)
+
+func TestYCbCr(t *testing.T) {
+ rects := []Rectangle{
+ Rect(0, 0, 16, 16),
+ Rect(1, 0, 16, 16),
+ Rect(0, 1, 16, 16),
+ Rect(1, 1, 16, 16),
+ Rect(1, 1, 15, 16),
+ Rect(1, 1, 16, 15),
+ Rect(1, 1, 15, 15),
+ Rect(2, 3, 14, 15),
+ Rect(7, 0, 7, 16),
+ Rect(0, 8, 16, 8),
+ Rect(0, 0, 10, 11),
+ Rect(5, 6, 16, 16),
+ Rect(7, 7, 8, 8),
+ Rect(7, 8, 8, 9),
+ Rect(8, 7, 9, 8),
+ Rect(8, 8, 9, 9),
+ Rect(7, 7, 17, 17),
+ Rect(8, 8, 17, 17),
+ Rect(9, 9, 17, 17),
+ Rect(10, 10, 17, 17),
+ }
+ subsampleRatios := []YCbCrSubsampleRatio{
+ YCbCrSubsampleRatio444,
+ YCbCrSubsampleRatio422,
+ YCbCrSubsampleRatio420,
+ YCbCrSubsampleRatio440,
+ YCbCrSubsampleRatio411,
+ YCbCrSubsampleRatio410,
+ }
+ deltas := []Point{
+ Pt(0, 0),
+ Pt(1000, 1001),
+ Pt(5001, -400),
+ Pt(-701, -801),
+ }
+ for _, r := range rects {
+ for _, subsampleRatio := range subsampleRatios {
+ for _, delta := range deltas {
+ testYCbCr(t, r, subsampleRatio, delta)
+ }
+ }
+ if testing.Short() {
+ break
+ }
+ }
+}
+
+func testYCbCr(t *testing.T, r Rectangle, subsampleRatio YCbCrSubsampleRatio, delta Point) {
+ // Create a YCbCr image m, whose bounds are r translated by (delta.X, delta.Y).
+ r1 := r.Add(delta)
+ m := NewYCbCr(r1, subsampleRatio)
+
+ // Test that the image buffer is reasonably small even if (delta.X, delta.Y) is far from the origin.
+ if len(m.Y) > 100*100 {
+ t.Errorf("r=%v, subsampleRatio=%v, delta=%v: image buffer is too large",
+ r, subsampleRatio, delta)
+ return
+ }
+
+ // Initialize m's pixels. For 422 and 420 subsampling, some of the Cb and Cr elements
+ // will be set multiple times. That's OK. We just want to avoid a uniform image.
+ for y := r1.Min.Y; y < r1.Max.Y; y++ {
+ for x := r1.Min.X; x < r1.Max.X; x++ {
+ yi := m.YOffset(x, y)
+ ci := m.COffset(x, y)
+ m.Y[yi] = uint8(16*y + x)
+ m.Cb[ci] = uint8(y + 16*x)
+ m.Cr[ci] = uint8(y + 16*x)
+ }
+ }
+
+ // Make various sub-images of m.
+ for y0 := delta.Y + 3; y0 < delta.Y+7; y0++ {
+ for y1 := delta.Y + 8; y1 < delta.Y+13; y1++ {
+ for x0 := delta.X + 3; x0 < delta.X+7; x0++ {
+ for x1 := delta.X + 8; x1 < delta.X+13; x1++ {
+ subRect := Rect(x0, y0, x1, y1)
+ sub := m.SubImage(subRect).(*YCbCr)
+
+ // For each point in the sub-image's bounds, check that m.At(x, y) equals sub.At(x, y).
+ for y := sub.Rect.Min.Y; y < sub.Rect.Max.Y; y++ {
+ for x := sub.Rect.Min.X; x < sub.Rect.Max.X; x++ {
+ color0 := m.At(x, y).(color.YCbCr)
+ color1 := sub.At(x, y).(color.YCbCr)
+ if color0 != color1 {
+ t.Errorf("r=%v, subsampleRatio=%v, delta=%v, x=%d, y=%d, color0=%v, color1=%v",
+ r, subsampleRatio, delta, x, y, color0, color1)
+ return
+ }
+ }
+ }
+ }
+ }
+ }
+ }
+}
+
+func TestYCbCrSlicesDontOverlap(t *testing.T) {
+ m := NewYCbCr(Rect(0, 0, 8, 8), YCbCrSubsampleRatio420)
+ names := []string{"Y", "Cb", "Cr"}
+ slices := [][]byte{
+ m.Y[:cap(m.Y)],
+ m.Cb[:cap(m.Cb)],
+ m.Cr[:cap(m.Cr)],
+ }
+ for i, slice := range slices {
+ want := uint8(10 + i)
+ for j := range slice {
+ slice[j] = want
+ }
+ }
+ for i, slice := range slices {
+ want := uint8(10 + i)
+ for j, got := range slice {
+ if got != want {
+ t.Fatalf("m.%s[%d]: got %d, want %d", names[i], j, got, want)
+ }
+ }
+ }
+}
diff --git a/go/src/io/example_test.go b/go/src/io/example_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..818020e9dec6dd1b11456d996f123403b8b9bcdf
--- /dev/null
+++ b/go/src/io/example_test.go
@@ -0,0 +1,284 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package io_test
+
+import (
+ "fmt"
+ "io"
+ "log"
+ "os"
+ "strings"
+)
+
+func ExampleCopy() {
+ r := strings.NewReader("some io.Reader stream to be read\n")
+
+ if _, err := io.Copy(os.Stdout, r); err != nil {
+ log.Fatal(err)
+ }
+
+ // Output:
+ // some io.Reader stream to be read
+}
+
+func ExampleCopyBuffer() {
+ r1 := strings.NewReader("first reader\n")
+ r2 := strings.NewReader("second reader\n")
+ buf := make([]byte, 8)
+
+ // buf is used here...
+ if _, err := io.CopyBuffer(os.Stdout, r1, buf); err != nil {
+ log.Fatal(err)
+ }
+
+ // ... reused here also. No need to allocate an extra buffer.
+ if _, err := io.CopyBuffer(os.Stdout, r2, buf); err != nil {
+ log.Fatal(err)
+ }
+
+ // Output:
+ // first reader
+ // second reader
+}
+
+func ExampleCopyN() {
+ r := strings.NewReader("some io.Reader stream to be read")
+
+ if _, err := io.CopyN(os.Stdout, r, 4); err != nil {
+ log.Fatal(err)
+ }
+
+ // Output:
+ // some
+}
+
+func ExampleReadAtLeast() {
+ r := strings.NewReader("some io.Reader stream to be read\n")
+
+ buf := make([]byte, 14)
+ if _, err := io.ReadAtLeast(r, buf, 4); err != nil {
+ log.Fatal(err)
+ }
+ fmt.Printf("%s\n", buf)
+
+ // buffer smaller than minimal read size.
+ shortBuf := make([]byte, 3)
+ if _, err := io.ReadAtLeast(r, shortBuf, 4); err != nil {
+ fmt.Println("error:", err)
+ }
+
+ // minimal read size bigger than io.Reader stream
+ longBuf := make([]byte, 64)
+ if _, err := io.ReadAtLeast(r, longBuf, 64); err != nil {
+ fmt.Println("error:", err)
+ }
+
+ // Output:
+ // some io.Reader
+ // error: short buffer
+ // error: unexpected EOF
+}
+
+func ExampleReadFull() {
+ r := strings.NewReader("some io.Reader stream to be read\n")
+
+ buf := make([]byte, 4)
+ if _, err := io.ReadFull(r, buf); err != nil {
+ log.Fatal(err)
+ }
+ fmt.Printf("%s\n", buf)
+
+ // minimal read size bigger than io.Reader stream
+ longBuf := make([]byte, 64)
+ if _, err := io.ReadFull(r, longBuf); err != nil {
+ fmt.Println("error:", err)
+ }
+
+ // Output:
+ // some
+ // error: unexpected EOF
+}
+
+func ExampleWriteString() {
+ if _, err := io.WriteString(os.Stdout, "Hello World"); err != nil {
+ log.Fatal(err)
+ }
+
+ // Output: Hello World
+}
+
+func ExampleLimitReader() {
+ r := strings.NewReader("some io.Reader stream to be read\n")
+ lr := io.LimitReader(r, 4)
+
+ if _, err := io.Copy(os.Stdout, lr); err != nil {
+ log.Fatal(err)
+ }
+
+ // Output:
+ // some
+}
+
+func ExampleMultiReader() {
+ r1 := strings.NewReader("first reader ")
+ r2 := strings.NewReader("second reader ")
+ r3 := strings.NewReader("third reader\n")
+ r := io.MultiReader(r1, r2, r3)
+
+ if _, err := io.Copy(os.Stdout, r); err != nil {
+ log.Fatal(err)
+ }
+
+ // Output:
+ // first reader second reader third reader
+}
+
+func ExampleTeeReader() {
+ var r io.Reader = strings.NewReader("some io.Reader stream to be read\n")
+
+ r = io.TeeReader(r, os.Stdout)
+
+ // Everything read from r will be copied to stdout.
+ if _, err := io.ReadAll(r); err != nil {
+ log.Fatal(err)
+ }
+
+ // Output:
+ // some io.Reader stream to be read
+}
+
+func ExampleSectionReader() {
+ r := strings.NewReader("some io.Reader stream to be read\n")
+ s := io.NewSectionReader(r, 5, 17)
+
+ if _, err := io.Copy(os.Stdout, s); err != nil {
+ log.Fatal(err)
+ }
+
+ // Output:
+ // io.Reader stream
+}
+
+func ExampleSectionReader_Read() {
+ r := strings.NewReader("some io.Reader stream to be read\n")
+ s := io.NewSectionReader(r, 5, 17)
+
+ buf := make([]byte, 9)
+ if _, err := s.Read(buf); err != nil {
+ log.Fatal(err)
+ }
+
+ fmt.Printf("%s\n", buf)
+
+ // Output:
+ // io.Reader
+}
+
+func ExampleSectionReader_ReadAt() {
+ r := strings.NewReader("some io.Reader stream to be read\n")
+ s := io.NewSectionReader(r, 5, 17)
+
+ buf := make([]byte, 6)
+ if _, err := s.ReadAt(buf, 10); err != nil {
+ log.Fatal(err)
+ }
+
+ fmt.Printf("%s\n", buf)
+
+ // Output:
+ // stream
+}
+
+func ExampleSectionReader_Seek() {
+ r := strings.NewReader("some io.Reader stream to be read\n")
+ s := io.NewSectionReader(r, 5, 17)
+
+ if _, err := s.Seek(10, io.SeekStart); err != nil {
+ log.Fatal(err)
+ }
+
+ if _, err := io.Copy(os.Stdout, s); err != nil {
+ log.Fatal(err)
+ }
+
+ // Output:
+ // stream
+}
+
+func ExampleSectionReader_Size() {
+ r := strings.NewReader("some io.Reader stream to be read\n")
+ s := io.NewSectionReader(r, 5, 17)
+
+ fmt.Println(s.Size())
+
+ // Output:
+ // 17
+}
+
+func ExampleSeeker_Seek() {
+ r := strings.NewReader("some io.Reader stream to be read\n")
+
+ r.Seek(5, io.SeekStart) // move to the 5th char from the start
+ if _, err := io.Copy(os.Stdout, r); err != nil {
+ log.Fatal(err)
+ }
+
+ r.Seek(-5, io.SeekEnd)
+ if _, err := io.Copy(os.Stdout, r); err != nil {
+ log.Fatal(err)
+ }
+
+ // Output:
+ // io.Reader stream to be read
+ // read
+}
+
+func ExampleMultiWriter() {
+ r := strings.NewReader("some io.Reader stream to be read\n")
+
+ var buf1, buf2 strings.Builder
+ w := io.MultiWriter(&buf1, &buf2)
+
+ if _, err := io.Copy(w, r); err != nil {
+ log.Fatal(err)
+ }
+
+ fmt.Print(buf1.String())
+ fmt.Print(buf2.String())
+
+ // Output:
+ // some io.Reader stream to be read
+ // some io.Reader stream to be read
+}
+
+func ExamplePipe() {
+ r, w := io.Pipe()
+
+ go func() {
+ fmt.Fprint(w, "some io.Reader stream to be read\n")
+ w.Close()
+ }()
+
+ if _, err := io.Copy(os.Stdout, r); err != nil {
+ log.Fatal(err)
+ }
+
+ // Output:
+ // some io.Reader stream to be read
+}
+
+func ExampleReadAll() {
+ r := strings.NewReader("Go is a general-purpose language designed with systems programming in mind.")
+
+ b, err := io.ReadAll(r)
+ if err != nil {
+ log.Fatal(err)
+ }
+
+ fmt.Printf("%s", b)
+
+ // Output:
+ // Go is a general-purpose language designed with systems programming in mind.
+}
diff --git a/go/src/io/export_test.go b/go/src/io/export_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..06853f975f577f15c3b3a2f532a195ce8b4679e6
--- /dev/null
+++ b/go/src/io/export_test.go
@@ -0,0 +1,10 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package io
+
+// exported for test
+var ErrInvalidWrite = errInvalidWrite
+var ErrWhence = errWhence
+var ErrOffset = errOffset
diff --git a/go/src/io/io.go b/go/src/io/io.go
new file mode 100644
index 0000000000000000000000000000000000000000..5b039e985789b77ddfdbbd75e9962b1c29293b86
--- /dev/null
+++ b/go/src/io/io.go
@@ -0,0 +1,750 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package io provides basic interfaces to I/O primitives.
+// Its primary job is to wrap existing implementations of such primitives,
+// such as those in package os, into shared public interfaces that
+// abstract the functionality, plus some other related primitives.
+//
+// Because these interfaces and primitives wrap lower-level operations with
+// various implementations, unless otherwise informed clients should not
+// assume they are safe for parallel execution.
+package io
+
+import (
+ "errors"
+ "sync"
+)
+
+// Seek whence values.
+const (
+ SeekStart = 0 // seek relative to the origin of the file
+ SeekCurrent = 1 // seek relative to the current offset
+ SeekEnd = 2 // seek relative to the end
+)
+
+// ErrShortWrite means that a write accepted fewer bytes than requested
+// but failed to return an explicit error.
+var ErrShortWrite = errors.New("short write")
+
+// errInvalidWrite means that a write returned an impossible count.
+var errInvalidWrite = errors.New("invalid write result")
+
+// ErrShortBuffer means that a read required a longer buffer than was provided.
+var ErrShortBuffer = errors.New("short buffer")
+
+// EOF is the error returned by Read when no more input is available.
+// (Read must return EOF itself, not an error wrapping EOF,
+// because callers will test for EOF using ==.)
+// Functions should return EOF only to signal a graceful end of input.
+// If the EOF occurs unexpectedly in a structured data stream,
+// the appropriate error is either [ErrUnexpectedEOF] or some other error
+// giving more detail.
+var EOF = errors.New("EOF")
+
+// ErrUnexpectedEOF means that EOF was encountered in the
+// middle of reading a fixed-size block or data structure.
+var ErrUnexpectedEOF = errors.New("unexpected EOF")
+
+// ErrNoProgress is returned by some clients of a [Reader] when
+// many calls to Read have failed to return any data or error,
+// usually the sign of a broken [Reader] implementation.
+var ErrNoProgress = errors.New("multiple Read calls return no data or error")
+
+// Reader is the interface that wraps the basic Read method.
+//
+// Read reads up to len(p) bytes into p. It returns the number of bytes
+// read (0 <= n <= len(p)) and any error encountered. Even if Read
+// returns n < len(p), it may use all of p as scratch space during the call.
+// If some data is available but not len(p) bytes, Read conventionally
+// returns what is available instead of waiting for more.
+//
+// When Read encounters an error or end-of-file condition after
+// successfully reading n > 0 bytes, it returns the number of
+// bytes read. It may return the (non-nil) error from the same call
+// or return the error (and n == 0) from a subsequent call.
+// An instance of this general case is that a Reader returning
+// a non-zero number of bytes at the end of the input stream may
+// return either err == EOF or err == nil. The next Read should
+// return 0, EOF.
+//
+// Callers should always process the n > 0 bytes returned before
+// considering the error err. Doing so correctly handles I/O errors
+// that happen after reading some bytes and also both of the
+// allowed EOF behaviors.
+//
+// If len(p) == 0, Read should always return n == 0. It may return a
+// non-nil error if some error condition is known, such as EOF.
+//
+// Implementations of Read are discouraged from returning a
+// zero byte count with a nil error, except when len(p) == 0.
+// Callers should treat a return of 0 and nil as indicating that
+// nothing happened; in particular it does not indicate EOF.
+//
+// Implementations must not retain p.
+type Reader interface {
+ Read(p []byte) (n int, err error)
+}
+
+// Writer is the interface that wraps the basic Write method.
+//
+// Write writes len(p) bytes from p to the underlying data stream.
+// It returns the number of bytes written from p (0 <= n <= len(p))
+// and any error encountered that caused the write to stop early.
+// Write must return a non-nil error if it returns n < len(p).
+// Write must not modify the slice data, even temporarily.
+//
+// Implementations must not retain p.
+type Writer interface {
+ Write(p []byte) (n int, err error)
+}
+
+// Closer is the interface that wraps the basic Close method.
+//
+// The behavior of Close after the first call is undefined.
+// Specific implementations may document their own behavior.
+type Closer interface {
+ Close() error
+}
+
+// Seeker is the interface that wraps the basic Seek method.
+//
+// Seek sets the offset for the next Read or Write to offset,
+// interpreted according to whence:
+// [SeekStart] means relative to the start of the file,
+// [SeekCurrent] means relative to the current offset, and
+// [SeekEnd] means relative to the end
+// (for example, offset = -2 specifies the penultimate byte of the file).
+// Seek returns the new offset relative to the start of the
+// file or an error, if any.
+//
+// Seeking to an offset before the start of the file is an error.
+// Seeking to any positive offset may be allowed, but if the new offset exceeds
+// the size of the underlying object the behavior of subsequent I/O operations
+// is implementation-dependent.
+type Seeker interface {
+ Seek(offset int64, whence int) (int64, error)
+}
+
+// ReadWriter is the interface that groups the basic Read and Write methods.
+type ReadWriter interface {
+ Reader
+ Writer
+}
+
+// ReadCloser is the interface that groups the basic Read and Close methods.
+type ReadCloser interface {
+ Reader
+ Closer
+}
+
+// WriteCloser is the interface that groups the basic Write and Close methods.
+type WriteCloser interface {
+ Writer
+ Closer
+}
+
+// ReadWriteCloser is the interface that groups the basic Read, Write and Close methods.
+type ReadWriteCloser interface {
+ Reader
+ Writer
+ Closer
+}
+
+// ReadSeeker is the interface that groups the basic Read and Seek methods.
+type ReadSeeker interface {
+ Reader
+ Seeker
+}
+
+// ReadSeekCloser is the interface that groups the basic Read, Seek and Close
+// methods.
+type ReadSeekCloser interface {
+ Reader
+ Seeker
+ Closer
+}
+
+// WriteSeeker is the interface that groups the basic Write and Seek methods.
+type WriteSeeker interface {
+ Writer
+ Seeker
+}
+
+// ReadWriteSeeker is the interface that groups the basic Read, Write and Seek methods.
+type ReadWriteSeeker interface {
+ Reader
+ Writer
+ Seeker
+}
+
+// ReaderFrom is the interface that wraps the ReadFrom method.
+//
+// ReadFrom reads data from r until EOF or error.
+// The return value n is the number of bytes read.
+// Any error except EOF encountered during the read is also returned.
+//
+// The [Copy] function uses [ReaderFrom] if available.
+type ReaderFrom interface {
+ ReadFrom(r Reader) (n int64, err error)
+}
+
+// WriterTo is the interface that wraps the WriteTo method.
+//
+// WriteTo writes data to w until there's no more data to write or
+// when an error occurs. The return value n is the number of bytes
+// written. Any error encountered during the write is also returned.
+//
+// The Copy function uses WriterTo if available.
+type WriterTo interface {
+ WriteTo(w Writer) (n int64, err error)
+}
+
+// ReaderAt is the interface that wraps the basic ReadAt method.
+//
+// ReadAt reads len(p) bytes into p starting at offset off in the
+// underlying input source. It returns the number of bytes
+// read (0 <= n <= len(p)) and any error encountered.
+//
+// When ReadAt returns n < len(p), it returns a non-nil error
+// explaining why more bytes were not returned. In this respect,
+// ReadAt is stricter than Read.
+//
+// Even if ReadAt returns n < len(p), it may use all of p as scratch
+// space during the call. If some data is available but not len(p) bytes,
+// ReadAt blocks until either all the data is available or an error occurs.
+// In this respect ReadAt is different from Read.
+//
+// If the n = len(p) bytes returned by ReadAt are at the end of the
+// input source, ReadAt may return either err == EOF or err == nil.
+//
+// If ReadAt is reading from an input source with a seek offset,
+// ReadAt should not affect nor be affected by the underlying
+// seek offset.
+//
+// Clients of ReadAt can execute parallel ReadAt calls on the
+// same input source.
+//
+// Implementations must not retain p.
+type ReaderAt interface {
+ ReadAt(p []byte, off int64) (n int, err error)
+}
+
+// WriterAt is the interface that wraps the basic WriteAt method.
+//
+// WriteAt writes len(p) bytes from p to the underlying data stream
+// at offset off. It returns the number of bytes written from p (0 <= n <= len(p))
+// and any error encountered that caused the write to stop early.
+// WriteAt must return a non-nil error if it returns n < len(p).
+//
+// If WriteAt is writing to a destination with a seek offset,
+// WriteAt should not affect nor be affected by the underlying
+// seek offset.
+//
+// Clients of WriteAt can execute parallel WriteAt calls on the same
+// destination if the ranges do not overlap.
+//
+// Implementations must not retain p.
+type WriterAt interface {
+ WriteAt(p []byte, off int64) (n int, err error)
+}
+
+// ByteReader is the interface that wraps the ReadByte method.
+//
+// ReadByte reads and returns the next byte from the input or
+// any error encountered. If ReadByte returns an error, no input
+// byte was consumed, and the returned byte value is undefined.
+//
+// ReadByte provides an efficient interface for byte-at-time
+// processing. A [Reader] that does not implement ByteReader
+// can be wrapped using bufio.NewReader to add this method.
+type ByteReader interface {
+ ReadByte() (byte, error)
+}
+
+// ByteScanner is the interface that adds the UnreadByte method to the
+// basic ReadByte method.
+//
+// UnreadByte causes the next call to ReadByte to return the last byte read.
+// If the last operation was not a successful call to ReadByte, UnreadByte may
+// return an error, unread the last byte read (or the byte prior to the
+// last-unread byte), or (in implementations that support the [Seeker] interface)
+// seek to one byte before the current offset.
+type ByteScanner interface {
+ ByteReader
+ UnreadByte() error
+}
+
+// ByteWriter is the interface that wraps the WriteByte method.
+type ByteWriter interface {
+ WriteByte(c byte) error
+}
+
+// RuneReader is the interface that wraps the ReadRune method.
+//
+// ReadRune reads a single encoded Unicode character
+// and returns the rune and its size in bytes. If no character is
+// available, err will be set.
+type RuneReader interface {
+ ReadRune() (r rune, size int, err error)
+}
+
+// RuneScanner is the interface that adds the UnreadRune method to the
+// basic ReadRune method.
+//
+// UnreadRune causes the next call to ReadRune to return the last rune read.
+// If the last operation was not a successful call to ReadRune, UnreadRune may
+// return an error, unread the last rune read (or the rune prior to the
+// last-unread rune), or (in implementations that support the [Seeker] interface)
+// seek to the start of the rune before the current offset.
+type RuneScanner interface {
+ RuneReader
+ UnreadRune() error
+}
+
+// StringWriter is the interface that wraps the WriteString method.
+type StringWriter interface {
+ WriteString(s string) (n int, err error)
+}
+
+// WriteString writes the contents of the string s to w, which accepts a slice of bytes.
+// If w implements [StringWriter], [StringWriter.WriteString] is invoked directly.
+// Otherwise, [Writer.Write] is called exactly once.
+func WriteString(w Writer, s string) (n int, err error) {
+ if sw, ok := w.(StringWriter); ok {
+ return sw.WriteString(s)
+ }
+ return w.Write([]byte(s))
+}
+
+// ReadAtLeast reads from r into buf until it has read at least min bytes.
+// It returns the number of bytes copied and an error if fewer bytes were read.
+// The error is EOF only if no bytes were read.
+// If an EOF happens after reading fewer than min bytes,
+// ReadAtLeast returns [ErrUnexpectedEOF].
+// If min is greater than the length of buf, ReadAtLeast returns [ErrShortBuffer].
+// On return, n >= min if and only if err == nil.
+// If r returns an error having read at least min bytes, the error is dropped.
+func ReadAtLeast(r Reader, buf []byte, min int) (n int, err error) {
+ if len(buf) < min {
+ return 0, ErrShortBuffer
+ }
+ for n < min && err == nil {
+ var nn int
+ nn, err = r.Read(buf[n:])
+ n += nn
+ }
+ if n >= min {
+ err = nil
+ } else if n > 0 && err == EOF {
+ err = ErrUnexpectedEOF
+ }
+ return
+}
+
+// ReadFull reads exactly len(buf) bytes from r into buf.
+// It returns the number of bytes copied and an error if fewer bytes were read.
+// The error is EOF only if no bytes were read.
+// If an EOF happens after reading some but not all the bytes,
+// ReadFull returns [ErrUnexpectedEOF].
+// On return, n == len(buf) if and only if err == nil.
+// If r returns an error having read at least len(buf) bytes, the error is dropped.
+func ReadFull(r Reader, buf []byte) (n int, err error) {
+ return ReadAtLeast(r, buf, len(buf))
+}
+
+// CopyN copies n bytes (or until an error) from src to dst.
+// It returns the number of bytes copied and the earliest
+// error encountered while copying.
+// On return, written == n if and only if err == nil.
+//
+// If dst implements [ReaderFrom], the copy is implemented using it.
+func CopyN(dst Writer, src Reader, n int64) (written int64, err error) {
+ written, err = Copy(dst, LimitReader(src, n))
+ if written == n {
+ return n, nil
+ }
+ if written < n && err == nil {
+ // src stopped early; must have been EOF.
+ err = EOF
+ }
+ return
+}
+
+// Copy copies from src to dst until either EOF is reached
+// on src or an error occurs. It returns the number of bytes
+// copied and the first error encountered while copying, if any.
+//
+// A successful Copy returns err == nil, not err == EOF.
+// Because Copy is defined to read from src until EOF, it does
+// not treat an EOF from Read as an error to be reported.
+//
+// If src implements [WriterTo],
+// the copy is implemented by calling src.WriteTo(dst).
+// Otherwise, if dst implements [ReaderFrom],
+// the copy is implemented by calling dst.ReadFrom(src).
+func Copy(dst Writer, src Reader) (written int64, err error) {
+ return copyBuffer(dst, src, nil)
+}
+
+// CopyBuffer is identical to Copy except that it stages through the
+// provided buffer (if one is required) rather than allocating a
+// temporary one. If buf is nil, one is allocated; otherwise if it has
+// zero length, CopyBuffer panics.
+//
+// If either src implements [WriterTo] or dst implements [ReaderFrom],
+// buf will not be used to perform the copy.
+func CopyBuffer(dst Writer, src Reader, buf []byte) (written int64, err error) {
+ if buf != nil && len(buf) == 0 {
+ panic("empty buffer in CopyBuffer")
+ }
+ return copyBuffer(dst, src, buf)
+}
+
+// copyBuffer is the actual implementation of Copy and CopyBuffer.
+// if buf is nil, one is allocated.
+func copyBuffer(dst Writer, src Reader, buf []byte) (written int64, err error) {
+ // If the reader has a WriteTo method, use it to do the copy.
+ // Avoids an allocation and a copy.
+ if wt, ok := src.(WriterTo); ok {
+ return wt.WriteTo(dst)
+ }
+ // Similarly, if the writer has a ReadFrom method, use it to do the copy.
+ if rf, ok := dst.(ReaderFrom); ok {
+ return rf.ReadFrom(src)
+ }
+ if buf == nil {
+ size := 32 * 1024
+ if l, ok := src.(*LimitedReader); ok && int64(size) > l.N {
+ if l.N < 1 {
+ size = 1
+ } else {
+ size = int(l.N)
+ }
+ }
+ buf = make([]byte, size)
+ }
+ for {
+ nr, er := src.Read(buf)
+ if nr > 0 {
+ nw, ew := dst.Write(buf[0:nr])
+ if nw < 0 || nr < nw {
+ nw = 0
+ if ew == nil {
+ ew = errInvalidWrite
+ }
+ }
+ written += int64(nw)
+ if ew != nil {
+ err = ew
+ break
+ }
+ if nr != nw {
+ err = ErrShortWrite
+ break
+ }
+ }
+ if er != nil {
+ if er != EOF {
+ err = er
+ }
+ break
+ }
+ }
+ return written, err
+}
+
+// LimitReader returns a Reader that reads from r
+// but stops with EOF after n bytes.
+// The underlying implementation is a *LimitedReader.
+func LimitReader(r Reader, n int64) Reader { return &LimitedReader{r, n} }
+
+// A LimitedReader reads from R but limits the amount of
+// data returned to just N bytes. Each call to Read
+// updates N to reflect the new amount remaining.
+// Read returns EOF when N <= 0 or when the underlying R returns EOF.
+type LimitedReader struct {
+ R Reader // underlying reader
+ N int64 // max bytes remaining
+}
+
+func (l *LimitedReader) Read(p []byte) (n int, err error) {
+ if l.N <= 0 {
+ return 0, EOF
+ }
+ if int64(len(p)) > l.N {
+ p = p[0:l.N]
+ }
+ n, err = l.R.Read(p)
+ l.N -= int64(n)
+ return
+}
+
+// NewSectionReader returns a [SectionReader] that reads from r
+// starting at offset off and stops with EOF after n bytes.
+func NewSectionReader(r ReaderAt, off int64, n int64) *SectionReader {
+ var remaining int64
+ const maxint64 = 1<<63 - 1
+ if off <= maxint64-n {
+ remaining = n + off
+ } else {
+ // Overflow, with no way to return error.
+ // Assume we can read up to an offset of 1<<63 - 1.
+ remaining = maxint64
+ }
+ return &SectionReader{r, off, off, remaining, n}
+}
+
+// SectionReader implements Read, Seek, and ReadAt on a section
+// of an underlying [ReaderAt].
+type SectionReader struct {
+ r ReaderAt // constant after creation
+ base int64 // constant after creation
+ off int64
+ limit int64 // constant after creation
+ n int64 // constant after creation
+}
+
+func (s *SectionReader) Read(p []byte) (n int, err error) {
+ if s.off >= s.limit {
+ return 0, EOF
+ }
+ if max := s.limit - s.off; int64(len(p)) > max {
+ p = p[0:max]
+ }
+ n, err = s.r.ReadAt(p, s.off)
+ s.off += int64(n)
+ return
+}
+
+var errWhence = errors.New("Seek: invalid whence")
+var errOffset = errors.New("Seek: invalid offset")
+
+func (s *SectionReader) Seek(offset int64, whence int) (int64, error) {
+ switch whence {
+ default:
+ return 0, errWhence
+ case SeekStart:
+ offset += s.base
+ case SeekCurrent:
+ offset += s.off
+ case SeekEnd:
+ offset += s.limit
+ }
+ if offset < s.base {
+ return 0, errOffset
+ }
+ s.off = offset
+ return offset - s.base, nil
+}
+
+func (s *SectionReader) ReadAt(p []byte, off int64) (n int, err error) {
+ if off < 0 || off >= s.Size() {
+ return 0, EOF
+ }
+ off += s.base
+ if max := s.limit - off; int64(len(p)) > max {
+ p = p[0:max]
+ n, err = s.r.ReadAt(p, off)
+ if err == nil {
+ err = EOF
+ }
+ return n, err
+ }
+ return s.r.ReadAt(p, off)
+}
+
+// Size returns the size of the section in bytes.
+func (s *SectionReader) Size() int64 { return s.limit - s.base }
+
+// Outer returns the underlying [ReaderAt] and offsets for the section.
+//
+// The returned values are the same that were passed to [NewSectionReader]
+// when the [SectionReader] was created.
+func (s *SectionReader) Outer() (r ReaderAt, off int64, n int64) {
+ return s.r, s.base, s.n
+}
+
+// An OffsetWriter maps writes at offset base to offset base+off in the underlying writer.
+type OffsetWriter struct {
+ w WriterAt
+ base int64 // the original offset
+ off int64 // the current offset
+}
+
+// NewOffsetWriter returns an [OffsetWriter] that writes to w
+// starting at offset off.
+func NewOffsetWriter(w WriterAt, off int64) *OffsetWriter {
+ return &OffsetWriter{w, off, off}
+}
+
+func (o *OffsetWriter) Write(p []byte) (n int, err error) {
+ n, err = o.w.WriteAt(p, o.off)
+ o.off += int64(n)
+ return
+}
+
+func (o *OffsetWriter) WriteAt(p []byte, off int64) (n int, err error) {
+ if off < 0 {
+ return 0, errOffset
+ }
+
+ off += o.base
+ return o.w.WriteAt(p, off)
+}
+
+func (o *OffsetWriter) Seek(offset int64, whence int) (int64, error) {
+ switch whence {
+ default:
+ return 0, errWhence
+ case SeekStart:
+ offset += o.base
+ case SeekCurrent:
+ offset += o.off
+ }
+ if offset < o.base {
+ return 0, errOffset
+ }
+ o.off = offset
+ return offset - o.base, nil
+}
+
+// TeeReader returns a [Reader] that writes to w what it reads from r.
+// All reads from r performed through it are matched with
+// corresponding writes to w. There is no internal buffering -
+// the write must complete before the read completes.
+// Any error encountered while writing is reported as a read error.
+func TeeReader(r Reader, w Writer) Reader {
+ return &teeReader{r, w}
+}
+
+type teeReader struct {
+ r Reader
+ w Writer
+}
+
+func (t *teeReader) Read(p []byte) (n int, err error) {
+ n, err = t.r.Read(p)
+ if n > 0 {
+ if n, err := t.w.Write(p[:n]); err != nil {
+ return n, err
+ }
+ }
+ return
+}
+
+// Discard is a [Writer] on which all Write calls succeed
+// without doing anything.
+var Discard Writer = discard{}
+
+type discard struct{}
+
+// discard implements ReaderFrom as an optimization so Copy to
+// io.Discard can avoid doing unnecessary work.
+var _ ReaderFrom = discard{}
+
+func (discard) Write(p []byte) (int, error) {
+ return len(p), nil
+}
+
+func (discard) WriteString(s string) (int, error) {
+ return len(s), nil
+}
+
+var blackHolePool = sync.Pool{
+ New: func() any {
+ b := make([]byte, 8192)
+ return &b
+ },
+}
+
+func (discard) ReadFrom(r Reader) (n int64, err error) {
+ bufp := blackHolePool.Get().(*[]byte)
+ readSize := 0
+ for {
+ readSize, err = r.Read(*bufp)
+ n += int64(readSize)
+ if err != nil {
+ blackHolePool.Put(bufp)
+ if err == EOF {
+ return n, nil
+ }
+ return
+ }
+ }
+}
+
+// NopCloser returns a [ReadCloser] with a no-op Close method wrapping
+// the provided [Reader] r.
+// If r implements [WriterTo], the returned [ReadCloser] will implement [WriterTo]
+// by forwarding calls to r.
+func NopCloser(r Reader) ReadCloser {
+ if _, ok := r.(WriterTo); ok {
+ return nopCloserWriterTo{r}
+ }
+ return nopCloser{r}
+}
+
+type nopCloser struct {
+ Reader
+}
+
+func (nopCloser) Close() error { return nil }
+
+type nopCloserWriterTo struct {
+ Reader
+}
+
+func (nopCloserWriterTo) Close() error { return nil }
+
+func (c nopCloserWriterTo) WriteTo(w Writer) (n int64, err error) {
+ return c.Reader.(WriterTo).WriteTo(w)
+}
+
+// ReadAll reads from r until an error or EOF and returns the data it read.
+// A successful call returns err == nil, not err == EOF. Because ReadAll is
+// defined to read from src until EOF, it does not treat an EOF from Read
+// as an error to be reported.
+func ReadAll(r Reader) ([]byte, error) {
+ // Build slices of exponentially growing size,
+ // then copy into a perfectly-sized slice at the end.
+ b := make([]byte, 0, 512)
+ // Starting with next equal to 256 (instead of say 512 or 1024)
+ // allows less memory usage for small inputs that finish in the
+ // early growth stages, but we grow the read sizes quickly such that
+ // it does not materially impact medium or large inputs.
+ next := 256
+ chunks := make([][]byte, 0, 4)
+ // Invariant: finalSize = sum(len(c) for c in chunks)
+ var finalSize int
+ for {
+ n, err := r.Read(b[len(b):cap(b)])
+ b = b[:len(b)+n]
+ if err != nil {
+ if err == EOF {
+ err = nil
+ }
+ if len(chunks) == 0 {
+ return b, err
+ }
+
+ // Build our final right-sized slice.
+ finalSize += len(b)
+ final := append([]byte(nil), make([]byte, finalSize)...)[:0]
+ for _, chunk := range chunks {
+ final = append(final, chunk...)
+ }
+ final = append(final, b...)
+ return final, err
+ }
+
+ if cap(b)-len(b) < cap(b)/16 {
+ // Move to the next intermediate slice.
+ chunks = append(chunks, b)
+ finalSize += len(b)
+ b = append([]byte(nil), make([]byte, next)...)[:0]
+ next += next / 2
+ }
+ }
+}
diff --git a/go/src/io/io_test.go b/go/src/io/io_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..38bec8243e7baa5e76a6fb128ba204785b082cab
--- /dev/null
+++ b/go/src/io/io_test.go
@@ -0,0 +1,694 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package io_test
+
+import (
+ "bytes"
+ "errors"
+ "fmt"
+ . "io"
+ "os"
+ "strings"
+ "sync"
+ "sync/atomic"
+ "testing"
+)
+
+// A version of bytes.Buffer without ReadFrom and WriteTo
+type Buffer struct {
+ bytes.Buffer
+ ReaderFrom // conflicts with and hides bytes.Buffer's ReaderFrom.
+ WriterTo // conflicts with and hides bytes.Buffer's WriterTo.
+}
+
+// Simple tests, primarily to verify the ReadFrom and WriteTo callouts inside Copy, CopyBuffer and CopyN.
+
+func TestCopy(t *testing.T) {
+ rb := new(Buffer)
+ wb := new(Buffer)
+ rb.WriteString("hello, world.")
+ Copy(wb, rb)
+ if wb.String() != "hello, world." {
+ t.Errorf("Copy did not work properly")
+ }
+}
+
+func TestCopyNegative(t *testing.T) {
+ rb := new(Buffer)
+ wb := new(Buffer)
+ rb.WriteString("hello")
+ Copy(wb, &LimitedReader{R: rb, N: -1})
+ if wb.String() != "" {
+ t.Errorf("Copy on LimitedReader with N<0 copied data")
+ }
+
+ CopyN(wb, rb, -1)
+ if wb.String() != "" {
+ t.Errorf("CopyN with N<0 copied data")
+ }
+}
+
+func TestCopyBuffer(t *testing.T) {
+ rb := new(Buffer)
+ wb := new(Buffer)
+ rb.WriteString("hello, world.")
+ CopyBuffer(wb, rb, make([]byte, 1)) // Tiny buffer to keep it honest.
+ if wb.String() != "hello, world." {
+ t.Errorf("CopyBuffer did not work properly")
+ }
+}
+
+func TestCopyBufferNil(t *testing.T) {
+ rb := new(Buffer)
+ wb := new(Buffer)
+ rb.WriteString("hello, world.")
+ CopyBuffer(wb, rb, nil) // Should allocate a buffer.
+ if wb.String() != "hello, world." {
+ t.Errorf("CopyBuffer did not work properly")
+ }
+}
+
+func TestCopyReadFrom(t *testing.T) {
+ rb := new(Buffer)
+ wb := new(bytes.Buffer) // implements ReadFrom.
+ rb.WriteString("hello, world.")
+ Copy(wb, rb)
+ if wb.String() != "hello, world." {
+ t.Errorf("Copy did not work properly")
+ }
+}
+
+func TestCopyWriteTo(t *testing.T) {
+ rb := new(bytes.Buffer) // implements WriteTo.
+ wb := new(Buffer)
+ rb.WriteString("hello, world.")
+ Copy(wb, rb)
+ if wb.String() != "hello, world." {
+ t.Errorf("Copy did not work properly")
+ }
+}
+
+// Version of bytes.Buffer that checks whether WriteTo was called or not
+type writeToChecker struct {
+ bytes.Buffer
+ writeToCalled bool
+}
+
+func (wt *writeToChecker) WriteTo(w Writer) (int64, error) {
+ wt.writeToCalled = true
+ return wt.Buffer.WriteTo(w)
+}
+
+// It's preferable to choose WriterTo over ReaderFrom, since a WriterTo can issue one large write,
+// while the ReaderFrom must read until EOF, potentially allocating when running out of buffer.
+// Make sure that we choose WriterTo when both are implemented.
+func TestCopyPriority(t *testing.T) {
+ rb := new(writeToChecker)
+ wb := new(bytes.Buffer)
+ rb.WriteString("hello, world.")
+ Copy(wb, rb)
+ if wb.String() != "hello, world." {
+ t.Errorf("Copy did not work properly")
+ } else if !rb.writeToCalled {
+ t.Errorf("WriteTo was not prioritized over ReadFrom")
+ }
+}
+
+type zeroErrReader struct {
+ err error
+}
+
+func (r zeroErrReader) Read(p []byte) (int, error) {
+ return copy(p, []byte{0}), r.err
+}
+
+type errWriter struct {
+ err error
+}
+
+func (w errWriter) Write([]byte) (int, error) {
+ return 0, w.err
+}
+
+// In case a Read results in an error with non-zero bytes read, and
+// the subsequent Write also results in an error, the error from Write
+// is returned, as it is the one that prevented progressing further.
+func TestCopyReadErrWriteErr(t *testing.T) {
+ er, ew := errors.New("readError"), errors.New("writeError")
+ r, w := zeroErrReader{err: er}, errWriter{err: ew}
+ n, err := Copy(w, r)
+ if n != 0 || err != ew {
+ t.Errorf("Copy(zeroErrReader, errWriter) = %d, %v; want 0, writeError", n, err)
+ }
+}
+
+func TestCopyN(t *testing.T) {
+ rb := new(Buffer)
+ wb := new(Buffer)
+ rb.WriteString("hello, world.")
+ CopyN(wb, rb, 5)
+ if wb.String() != "hello" {
+ t.Errorf("CopyN did not work properly")
+ }
+}
+
+func TestCopyNReadFrom(t *testing.T) {
+ rb := new(Buffer)
+ wb := new(bytes.Buffer) // implements ReadFrom.
+ rb.WriteString("hello")
+ CopyN(wb, rb, 5)
+ if wb.String() != "hello" {
+ t.Errorf("CopyN did not work properly")
+ }
+}
+
+func TestCopyNWriteTo(t *testing.T) {
+ rb := new(bytes.Buffer) // implements WriteTo.
+ wb := new(Buffer)
+ rb.WriteString("hello, world.")
+ CopyN(wb, rb, 5)
+ if wb.String() != "hello" {
+ t.Errorf("CopyN did not work properly")
+ }
+}
+
+func BenchmarkCopyNSmall(b *testing.B) {
+ bs := bytes.Repeat([]byte{0}, 512+1)
+ rd := bytes.NewReader(bs)
+ buf := new(Buffer)
+ b.ResetTimer()
+
+ for i := 0; i < b.N; i++ {
+ CopyN(buf, rd, 512)
+ rd.Reset(bs)
+ }
+}
+
+func BenchmarkCopyNLarge(b *testing.B) {
+ bs := bytes.Repeat([]byte{0}, (32*1024)+1)
+ rd := bytes.NewReader(bs)
+ buf := new(Buffer)
+ b.ResetTimer()
+
+ for i := 0; i < b.N; i++ {
+ CopyN(buf, rd, 32*1024)
+ rd.Reset(bs)
+ }
+}
+
+type noReadFrom struct {
+ w Writer
+}
+
+func (w *noReadFrom) Write(p []byte) (n int, err error) {
+ return w.w.Write(p)
+}
+
+type wantedAndErrReader struct{}
+
+func (wantedAndErrReader) Read(p []byte) (int, error) {
+ return len(p), errors.New("wantedAndErrReader error")
+}
+
+func TestCopyNEOF(t *testing.T) {
+ // Test that EOF behavior is the same regardless of whether
+ // argument to CopyN has ReadFrom.
+
+ b := new(bytes.Buffer)
+
+ n, err := CopyN(&noReadFrom{b}, strings.NewReader("foo"), 3)
+ if n != 3 || err != nil {
+ t.Errorf("CopyN(noReadFrom, foo, 3) = %d, %v; want 3, nil", n, err)
+ }
+
+ n, err = CopyN(&noReadFrom{b}, strings.NewReader("foo"), 4)
+ if n != 3 || err != EOF {
+ t.Errorf("CopyN(noReadFrom, foo, 4) = %d, %v; want 3, EOF", n, err)
+ }
+
+ n, err = CopyN(b, strings.NewReader("foo"), 3) // b has read from
+ if n != 3 || err != nil {
+ t.Errorf("CopyN(bytes.Buffer, foo, 3) = %d, %v; want 3, nil", n, err)
+ }
+
+ n, err = CopyN(b, strings.NewReader("foo"), 4) // b has read from
+ if n != 3 || err != EOF {
+ t.Errorf("CopyN(bytes.Buffer, foo, 4) = %d, %v; want 3, EOF", n, err)
+ }
+
+ n, err = CopyN(b, wantedAndErrReader{}, 5)
+ if n != 5 || err != nil {
+ t.Errorf("CopyN(bytes.Buffer, wantedAndErrReader, 5) = %d, %v; want 5, nil", n, err)
+ }
+
+ n, err = CopyN(&noReadFrom{b}, wantedAndErrReader{}, 5)
+ if n != 5 || err != nil {
+ t.Errorf("CopyN(noReadFrom, wantedAndErrReader, 5) = %d, %v; want 5, nil", n, err)
+ }
+}
+
+func TestReadAtLeast(t *testing.T) {
+ var rb bytes.Buffer
+ testReadAtLeast(t, &rb)
+}
+
+// A version of bytes.Buffer that returns n > 0, err on Read
+// when the input is exhausted.
+type dataAndErrorBuffer struct {
+ err error
+ bytes.Buffer
+}
+
+func (r *dataAndErrorBuffer) Read(p []byte) (n int, err error) {
+ n, err = r.Buffer.Read(p)
+ if n > 0 && r.Buffer.Len() == 0 && err == nil {
+ err = r.err
+ }
+ return
+}
+
+func TestReadAtLeastWithDataAndEOF(t *testing.T) {
+ var rb dataAndErrorBuffer
+ rb.err = EOF
+ testReadAtLeast(t, &rb)
+}
+
+func TestReadAtLeastWithDataAndError(t *testing.T) {
+ var rb dataAndErrorBuffer
+ rb.err = fmt.Errorf("fake error")
+ testReadAtLeast(t, &rb)
+}
+
+func testReadAtLeast(t *testing.T, rb ReadWriter) {
+ rb.Write([]byte("0123"))
+ buf := make([]byte, 2)
+ n, err := ReadAtLeast(rb, buf, 2)
+ if err != nil {
+ t.Error(err)
+ }
+ if n != 2 {
+ t.Errorf("expected to have read 2 bytes, got %v", n)
+ }
+ n, err = ReadAtLeast(rb, buf, 4)
+ if err != ErrShortBuffer {
+ t.Errorf("expected ErrShortBuffer got %v", err)
+ }
+ if n != 0 {
+ t.Errorf("expected to have read 0 bytes, got %v", n)
+ }
+ n, err = ReadAtLeast(rb, buf, 1)
+ if err != nil {
+ t.Error(err)
+ }
+ if n != 2 {
+ t.Errorf("expected to have read 2 bytes, got %v", n)
+ }
+ n, err = ReadAtLeast(rb, buf, 2)
+ if err != EOF {
+ t.Errorf("expected EOF, got %v", err)
+ }
+ if n != 0 {
+ t.Errorf("expected to have read 0 bytes, got %v", n)
+ }
+ rb.Write([]byte("4"))
+ n, err = ReadAtLeast(rb, buf, 2)
+ want := ErrUnexpectedEOF
+ if rb, ok := rb.(*dataAndErrorBuffer); ok && rb.err != EOF {
+ want = rb.err
+ }
+ if err != want {
+ t.Errorf("expected %v, got %v", want, err)
+ }
+ if n != 1 {
+ t.Errorf("expected to have read 1 bytes, got %v", n)
+ }
+}
+
+func TestTeeReader(t *testing.T) {
+ src := []byte("hello, world")
+ dst := make([]byte, len(src))
+ rb := bytes.NewBuffer(src)
+ wb := new(bytes.Buffer)
+ r := TeeReader(rb, wb)
+ if n, err := ReadFull(r, dst); err != nil || n != len(src) {
+ t.Fatalf("ReadFull(r, dst) = %d, %v; want %d, nil", n, err, len(src))
+ }
+ if !bytes.Equal(dst, src) {
+ t.Errorf("bytes read = %q want %q", dst, src)
+ }
+ if !bytes.Equal(wb.Bytes(), src) {
+ t.Errorf("bytes written = %q want %q", wb.Bytes(), src)
+ }
+ if n, err := r.Read(dst); n != 0 || err != EOF {
+ t.Errorf("r.Read at EOF = %d, %v want 0, EOF", n, err)
+ }
+ rb = bytes.NewBuffer(src)
+ pr, pw := Pipe()
+ pr.Close()
+ r = TeeReader(rb, pw)
+ if n, err := ReadFull(r, dst); n != 0 || err != ErrClosedPipe {
+ t.Errorf("closed tee: ReadFull(r, dst) = %d, %v; want 0, EPIPE", n, err)
+ }
+}
+
+func TestSectionReader_ReadAt(t *testing.T) {
+ dat := "a long sample data, 1234567890"
+ tests := []struct {
+ data string
+ off int
+ n int
+ bufLen int
+ at int
+ exp string
+ err error
+ }{
+ {data: "", off: 0, n: 10, bufLen: 2, at: 0, exp: "", err: EOF},
+ {data: dat, off: 0, n: len(dat), bufLen: 0, at: 0, exp: "", err: nil},
+ {data: dat, off: len(dat), n: 1, bufLen: 1, at: 0, exp: "", err: EOF},
+ {data: dat, off: 0, n: len(dat) + 2, bufLen: len(dat), at: 0, exp: dat, err: nil},
+ {data: dat, off: 0, n: len(dat), bufLen: len(dat) / 2, at: 0, exp: dat[:len(dat)/2], err: nil},
+ {data: dat, off: 0, n: len(dat), bufLen: len(dat), at: 0, exp: dat, err: nil},
+ {data: dat, off: 0, n: len(dat), bufLen: len(dat) / 2, at: 2, exp: dat[2 : 2+len(dat)/2], err: nil},
+ {data: dat, off: 3, n: len(dat), bufLen: len(dat) / 2, at: 2, exp: dat[5 : 5+len(dat)/2], err: nil},
+ {data: dat, off: 3, n: len(dat) / 2, bufLen: len(dat)/2 - 2, at: 2, exp: dat[5 : 5+len(dat)/2-2], err: nil},
+ {data: dat, off: 3, n: len(dat) / 2, bufLen: len(dat)/2 + 2, at: 2, exp: dat[5 : 5+len(dat)/2-2], err: EOF},
+ {data: dat, off: 0, n: 0, bufLen: 0, at: -1, exp: "", err: EOF},
+ {data: dat, off: 0, n: 0, bufLen: 0, at: 1, exp: "", err: EOF},
+ }
+ for i, tt := range tests {
+ r := strings.NewReader(tt.data)
+ s := NewSectionReader(r, int64(tt.off), int64(tt.n))
+ buf := make([]byte, tt.bufLen)
+ if n, err := s.ReadAt(buf, int64(tt.at)); n != len(tt.exp) || string(buf[:n]) != tt.exp || err != tt.err {
+ t.Fatalf("%d: ReadAt(%d) = %q, %v; expected %q, %v", i, tt.at, buf[:n], err, tt.exp, tt.err)
+ }
+ if _r, off, n := s.Outer(); _r != r || off != int64(tt.off) || n != int64(tt.n) {
+ t.Fatalf("%d: Outer() = %v, %d, %d; expected %v, %d, %d", i, _r, off, n, r, tt.off, tt.n)
+ }
+ }
+}
+
+func TestSectionReader_Seek(t *testing.T) {
+ // Verifies that NewSectionReader's Seeker behaves like bytes.NewReader (which is like strings.NewReader)
+ br := bytes.NewReader([]byte("foo"))
+ sr := NewSectionReader(br, 0, int64(len("foo")))
+
+ for _, whence := range []int{SeekStart, SeekCurrent, SeekEnd} {
+ for offset := int64(-3); offset <= 4; offset++ {
+ brOff, brErr := br.Seek(offset, whence)
+ srOff, srErr := sr.Seek(offset, whence)
+ if (brErr != nil) != (srErr != nil) || brOff != srOff {
+ t.Errorf("For whence %d, offset %d: bytes.Reader.Seek = (%v, %v) != SectionReader.Seek = (%v, %v)",
+ whence, offset, brOff, brErr, srErr, srOff)
+ }
+ }
+ }
+
+ // And verify we can just seek past the end and get an EOF
+ got, err := sr.Seek(100, SeekStart)
+ if err != nil || got != 100 {
+ t.Errorf("Seek = %v, %v; want 100, nil", got, err)
+ }
+
+ n, err := sr.Read(make([]byte, 10))
+ if n != 0 || err != EOF {
+ t.Errorf("Read = %v, %v; want 0, EOF", n, err)
+ }
+}
+
+func TestSectionReader_Size(t *testing.T) {
+ tests := []struct {
+ data string
+ want int64
+ }{
+ {"a long sample data, 1234567890", 30},
+ {"", 0},
+ }
+
+ for _, tt := range tests {
+ r := strings.NewReader(tt.data)
+ sr := NewSectionReader(r, 0, int64(len(tt.data)))
+ if got := sr.Size(); got != tt.want {
+ t.Errorf("Size = %v; want %v", got, tt.want)
+ }
+ }
+}
+
+func TestSectionReader_Max(t *testing.T) {
+ r := strings.NewReader("abcdef")
+ const maxint64 = 1<<63 - 1
+ sr := NewSectionReader(r, 3, maxint64)
+ n, err := sr.Read(make([]byte, 3))
+ if n != 3 || err != nil {
+ t.Errorf("Read = %v %v, want 3, nil", n, err)
+ }
+ n, err = sr.Read(make([]byte, 3))
+ if n != 0 || err != EOF {
+ t.Errorf("Read = %v, %v, want 0, EOF", n, err)
+ }
+ if _r, off, n := sr.Outer(); _r != r || off != 3 || n != maxint64 {
+ t.Fatalf("Outer = %v, %d, %d; expected %v, %d, %d", _r, off, n, r, 3, int64(maxint64))
+ }
+}
+
+// largeWriter returns an invalid count that is larger than the number
+// of bytes provided (issue 39978).
+type largeWriter struct {
+ err error
+}
+
+func (w largeWriter) Write(p []byte) (int, error) {
+ return len(p) + 1, w.err
+}
+
+func TestCopyLargeWriter(t *testing.T) {
+ want := ErrInvalidWrite
+ rb := new(Buffer)
+ wb := largeWriter{}
+ rb.WriteString("hello, world.")
+ if _, err := Copy(wb, rb); err != want {
+ t.Errorf("Copy error: got %v, want %v", err, want)
+ }
+
+ want = errors.New("largeWriterError")
+ rb = new(Buffer)
+ wb = largeWriter{err: want}
+ rb.WriteString("hello, world.")
+ if _, err := Copy(wb, rb); err != want {
+ t.Errorf("Copy error: got %v, want %v", err, want)
+ }
+}
+
+func TestNopCloserWriterToForwarding(t *testing.T) {
+ for _, tc := range [...]struct {
+ Name string
+ r Reader
+ }{
+ {"not a WriterTo", Reader(nil)},
+ {"a WriterTo", struct {
+ Reader
+ WriterTo
+ }{}},
+ } {
+ nc := NopCloser(tc.r)
+
+ _, expected := tc.r.(WriterTo)
+ _, got := nc.(WriterTo)
+ if expected != got {
+ t.Errorf("NopCloser incorrectly forwards WriterTo for %s, got %t want %t", tc.Name, got, expected)
+ }
+ }
+}
+
+func TestOffsetWriter_Seek(t *testing.T) {
+ tmpfilename := "TestOffsetWriter_Seek"
+ tmpfile, err := os.CreateTemp(t.TempDir(), tmpfilename)
+ if err != nil {
+ t.Fatalf("CreateTemp(%s) failed: %v", tmpfilename, err)
+ }
+ defer tmpfile.Close()
+ w := NewOffsetWriter(tmpfile, 0)
+
+ // Should throw error errWhence if whence is not valid
+ t.Run("errWhence", func(t *testing.T) {
+ for _, whence := range []int{-3, -2, -1, 3, 4, 5} {
+ var offset int64 = 0
+ gotOff, gotErr := w.Seek(offset, whence)
+ if gotOff != 0 || gotErr != ErrWhence {
+ t.Errorf("For whence %d, offset %d, OffsetWriter.Seek got: (%d, %v), want: (%d, %v)",
+ whence, offset, gotOff, gotErr, 0, ErrWhence)
+ }
+ }
+ })
+
+ // Should throw error errOffset if offset is negative
+ t.Run("errOffset", func(t *testing.T) {
+ for _, whence := range []int{SeekStart, SeekCurrent} {
+ for offset := int64(-3); offset < 0; offset++ {
+ gotOff, gotErr := w.Seek(offset, whence)
+ if gotOff != 0 || gotErr != ErrOffset {
+ t.Errorf("For whence %d, offset %d, OffsetWriter.Seek got: (%d, %v), want: (%d, %v)",
+ whence, offset, gotOff, gotErr, 0, ErrOffset)
+ }
+ }
+ }
+ })
+
+ // Normal tests
+ t.Run("normal", func(t *testing.T) {
+ tests := []struct {
+ offset int64
+ whence int
+ returnOff int64
+ }{
+ // keep in order
+ {whence: SeekStart, offset: 1, returnOff: 1},
+ {whence: SeekStart, offset: 2, returnOff: 2},
+ {whence: SeekStart, offset: 3, returnOff: 3},
+ {whence: SeekCurrent, offset: 1, returnOff: 4},
+ {whence: SeekCurrent, offset: 2, returnOff: 6},
+ {whence: SeekCurrent, offset: 3, returnOff: 9},
+ }
+ for idx, tt := range tests {
+ gotOff, gotErr := w.Seek(tt.offset, tt.whence)
+ if gotOff != tt.returnOff || gotErr != nil {
+ t.Errorf("%d:: For whence %d, offset %d, OffsetWriter.Seek got: (%d, %v), want: (%d, )",
+ idx+1, tt.whence, tt.offset, gotOff, gotErr, tt.returnOff)
+ }
+ }
+ })
+}
+
+func TestOffsetWriter_WriteAt(t *testing.T) {
+ const content = "0123456789ABCDEF"
+ contentSize := int64(len(content))
+ tmpdir := t.TempDir()
+
+ work := func(off, at int64) {
+ position := fmt.Sprintf("off_%d_at_%d", off, at)
+ tmpfile, err := os.CreateTemp(tmpdir, position)
+ if err != nil {
+ t.Fatalf("CreateTemp(%s) failed: %v", position, err)
+ }
+ defer tmpfile.Close()
+
+ var writeN int64
+ var wg sync.WaitGroup
+ // Concurrent writes, one byte at a time
+ for step, value := range []byte(content) {
+ wg.Add(1)
+ go func(wg *sync.WaitGroup, tmpfile *os.File, value byte, off, at int64, step int) {
+ defer wg.Done()
+
+ w := NewOffsetWriter(tmpfile, off)
+ n, e := w.WriteAt([]byte{value}, at+int64(step))
+ if e != nil {
+ t.Errorf("WriteAt failed. off: %d, at: %d, step: %d\n error: %v", off, at, step, e)
+ }
+ atomic.AddInt64(&writeN, int64(n))
+ }(&wg, tmpfile, value, off, at, step)
+ }
+ wg.Wait()
+
+ // Read one more byte to reach EOF
+ buf := make([]byte, contentSize+1)
+ readN, err := tmpfile.ReadAt(buf, off+at)
+ if err != EOF {
+ t.Fatalf("ReadAt failed: %v", err)
+ }
+ readContent := string(buf[:contentSize])
+ if writeN != int64(readN) || writeN != contentSize || readContent != content {
+ t.Fatalf("%s:: WriteAt(%s, %d) error. \ngot n: %v, content: %s \nexpected n: %v, content: %v",
+ position, content, at, readN, readContent, contentSize, content)
+ }
+ }
+ for off := int64(0); off < 2; off++ {
+ for at := int64(0); at < 2; at++ {
+ work(off, at)
+ }
+ }
+}
+
+func TestWriteAt_PositionPriorToBase(t *testing.T) {
+ tmpdir := t.TempDir()
+ tmpfilename := "TestOffsetWriter_WriteAt"
+ tmpfile, err := os.CreateTemp(tmpdir, tmpfilename)
+ if err != nil {
+ t.Fatalf("CreateTemp(%s) failed: %v", tmpfilename, err)
+ }
+ defer tmpfile.Close()
+
+ // start writing position in OffsetWriter
+ offset := int64(10)
+ // position we want to write to the tmpfile
+ at := int64(-1)
+ w := NewOffsetWriter(tmpfile, offset)
+ _, e := w.WriteAt([]byte("hello"), at)
+ if e == nil {
+ t.Errorf("error expected to be not nil")
+ }
+}
+
+func TestOffsetWriter_Write(t *testing.T) {
+ const content = "0123456789ABCDEF"
+ contentSize := len(content)
+ tmpdir := t.TempDir()
+
+ makeOffsetWriter := func(name string) (*OffsetWriter, *os.File) {
+ tmpfilename := "TestOffsetWriter_Write_" + name
+ tmpfile, err := os.CreateTemp(tmpdir, tmpfilename)
+ if err != nil {
+ t.Fatalf("CreateTemp(%s) failed: %v", tmpfilename, err)
+ }
+ return NewOffsetWriter(tmpfile, 0), tmpfile
+ }
+ checkContent := func(name string, f *os.File) {
+ // Read one more byte to reach EOF
+ buf := make([]byte, contentSize+1)
+ readN, err := f.ReadAt(buf, 0)
+ if err != EOF {
+ t.Fatalf("ReadAt failed, err: %v", err)
+ }
+ readContent := string(buf[:contentSize])
+ if readN != contentSize || readContent != content {
+ t.Fatalf("%s error. \ngot n: %v, content: %s \nexpected n: %v, content: %v",
+ name, readN, readContent, contentSize, content)
+ }
+ }
+
+ var name string
+ name = "Write"
+ t.Run(name, func(t *testing.T) {
+ // Write directly (off: 0, at: 0)
+ // Write content to file
+ w, f := makeOffsetWriter(name)
+ defer f.Close()
+ for _, value := range []byte(content) {
+ n, err := w.Write([]byte{value})
+ if err != nil {
+ t.Fatalf("Write failed, n: %d, err: %v", n, err)
+ }
+ }
+ checkContent(name, f)
+
+ // Copy -> Write
+ // Copy file f to file f2
+ name = "Copy"
+ w2, f2 := makeOffsetWriter(name)
+ defer f2.Close()
+ Copy(w2, f)
+ checkContent(name, f2)
+ })
+
+ // Copy -> WriteTo -> Write
+ // Note: strings.Reader implements the io.WriterTo interface.
+ name = "Write_Of_Copy_WriteTo"
+ t.Run(name, func(t *testing.T) {
+ w, f := makeOffsetWriter(name)
+ defer f.Close()
+ Copy(w, strings.NewReader(content))
+ checkContent(name, f)
+ })
+}
diff --git a/go/src/io/multi.go b/go/src/io/multi.go
new file mode 100644
index 0000000000000000000000000000000000000000..07a9afffda38272d264a47af01afb37b827236c7
--- /dev/null
+++ b/go/src/io/multi.go
@@ -0,0 +1,137 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package io
+
+type eofReader struct{}
+
+func (eofReader) Read([]byte) (int, error) {
+ return 0, EOF
+}
+
+type multiReader struct {
+ readers []Reader
+}
+
+func (mr *multiReader) Read(p []byte) (n int, err error) {
+ for len(mr.readers) > 0 {
+ // Optimization to flatten nested multiReaders (Issue 13558).
+ if len(mr.readers) == 1 {
+ if r, ok := mr.readers[0].(*multiReader); ok {
+ mr.readers = r.readers
+ continue
+ }
+ }
+ n, err = mr.readers[0].Read(p)
+ if err == EOF {
+ // Use eofReader instead of nil to avoid nil panic
+ // after performing flatten (Issue 18232).
+ mr.readers[0] = eofReader{} // permit earlier GC
+ mr.readers = mr.readers[1:]
+ }
+ if n > 0 || err != EOF {
+ if err == EOF && len(mr.readers) > 0 {
+ // Don't return EOF yet. More readers remain.
+ err = nil
+ }
+ return
+ }
+ }
+ return 0, EOF
+}
+
+func (mr *multiReader) WriteTo(w Writer) (sum int64, err error) {
+ return mr.writeToWithBuffer(w, make([]byte, 1024*32))
+}
+
+func (mr *multiReader) writeToWithBuffer(w Writer, buf []byte) (sum int64, err error) {
+ for i, r := range mr.readers {
+ var n int64
+ if subMr, ok := r.(*multiReader); ok { // reuse buffer with nested multiReaders
+ n, err = subMr.writeToWithBuffer(w, buf)
+ } else {
+ n, err = copyBuffer(w, r, buf)
+ }
+ sum += n
+ if err != nil {
+ mr.readers = mr.readers[i:] // permit resume / retry after error
+ return sum, err
+ }
+ mr.readers[i] = nil // permit early GC
+ }
+ mr.readers = nil
+ return sum, nil
+}
+
+var _ WriterTo = (*multiReader)(nil)
+
+// MultiReader returns a Reader that's the logical concatenation of
+// the provided input readers. They're read sequentially. Once all
+// inputs have returned EOF, Read will return EOF. If any of the readers
+// return a non-nil, non-EOF error, Read will return that error.
+func MultiReader(readers ...Reader) Reader {
+ r := make([]Reader, len(readers))
+ copy(r, readers)
+ return &multiReader{r}
+}
+
+type multiWriter struct {
+ writers []Writer
+}
+
+func (t *multiWriter) Write(p []byte) (n int, err error) {
+ for _, w := range t.writers {
+ n, err = w.Write(p)
+ if err != nil {
+ return
+ }
+ if n != len(p) {
+ err = ErrShortWrite
+ return
+ }
+ }
+ return len(p), nil
+}
+
+var _ StringWriter = (*multiWriter)(nil)
+
+func (t *multiWriter) WriteString(s string) (n int, err error) {
+ var p []byte // lazily initialized if/when needed
+ for _, w := range t.writers {
+ if sw, ok := w.(StringWriter); ok {
+ n, err = sw.WriteString(s)
+ } else {
+ if p == nil {
+ p = []byte(s)
+ }
+ n, err = w.Write(p)
+ }
+ if err != nil {
+ return
+ }
+ if n != len(s) {
+ err = ErrShortWrite
+ return
+ }
+ }
+ return len(s), nil
+}
+
+// MultiWriter creates a writer that duplicates its writes to all the
+// provided writers, similar to the Unix tee(1) command.
+//
+// Each write is written to each listed writer, one at a time.
+// If a listed writer returns an error, that overall write operation
+// stops and returns the error; it does not continue down the list.
+func MultiWriter(writers ...Writer) Writer {
+ allWriters := make([]Writer, 0, len(writers))
+ for _, w := range writers {
+ if mw, ok := w.(*multiWriter); ok {
+ allWriters = append(allWriters, mw.writers...)
+ } else {
+ allWriters = append(allWriters, w)
+ }
+ }
+ return &multiWriter{allWriters}
+}
diff --git a/go/src/io/multi_test.go b/go/src/io/multi_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..934a6ec785fda4eddcc6d0308f523317207819f1
--- /dev/null
+++ b/go/src/io/multi_test.go
@@ -0,0 +1,377 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package io_test
+
+import (
+ "bytes"
+ "crypto/sha1"
+ "errors"
+ "fmt"
+ . "io"
+ "runtime"
+ "strings"
+ "testing"
+ "time"
+)
+
+func TestMultiReader(t *testing.T) {
+ var mr Reader
+ var buf []byte
+ nread := 0
+ withFooBar := func(tests func()) {
+ r1 := strings.NewReader("foo ")
+ r2 := strings.NewReader("")
+ r3 := strings.NewReader("bar")
+ mr = MultiReader(r1, r2, r3)
+ buf = make([]byte, 20)
+ tests()
+ }
+ expectRead := func(size int, expected string, eerr error) {
+ nread++
+ n, gerr := mr.Read(buf[0:size])
+ if n != len(expected) {
+ t.Errorf("#%d, expected %d bytes; got %d",
+ nread, len(expected), n)
+ }
+ got := string(buf[0:n])
+ if got != expected {
+ t.Errorf("#%d, expected %q; got %q",
+ nread, expected, got)
+ }
+ if gerr != eerr {
+ t.Errorf("#%d, expected error %v; got %v",
+ nread, eerr, gerr)
+ }
+ buf = buf[n:]
+ }
+ withFooBar(func() {
+ expectRead(2, "fo", nil)
+ expectRead(5, "o ", nil)
+ expectRead(5, "bar", nil)
+ expectRead(5, "", EOF)
+ })
+ withFooBar(func() {
+ expectRead(4, "foo ", nil)
+ expectRead(1, "b", nil)
+ expectRead(3, "ar", nil)
+ expectRead(1, "", EOF)
+ })
+ withFooBar(func() {
+ expectRead(5, "foo ", nil)
+ })
+}
+
+func TestMultiReaderAsWriterTo(t *testing.T) {
+ mr := MultiReader(
+ strings.NewReader("foo "),
+ MultiReader( // Tickle the buffer reusing codepath
+ strings.NewReader(""),
+ strings.NewReader("bar"),
+ ),
+ )
+ mrAsWriterTo, ok := mr.(WriterTo)
+ if !ok {
+ t.Fatalf("expected cast to WriterTo to succeed")
+ }
+ sink := &strings.Builder{}
+ n, err := mrAsWriterTo.WriteTo(sink)
+ if err != nil {
+ t.Fatalf("expected no error; got %v", err)
+ }
+ if n != 7 {
+ t.Errorf("expected read 7 bytes; got %d", n)
+ }
+ if result := sink.String(); result != "foo bar" {
+ t.Errorf(`expected "foo bar"; got %q`, result)
+ }
+}
+
+func TestMultiWriter(t *testing.T) {
+ sink := new(bytes.Buffer)
+ // Hide bytes.Buffer's WriteString method:
+ testMultiWriter(t, struct {
+ Writer
+ fmt.Stringer
+ }{sink, sink})
+}
+
+func TestMultiWriter_String(t *testing.T) {
+ testMultiWriter(t, new(bytes.Buffer))
+}
+
+// Test that a multiWriter.WriteString calls results in at most 1 allocation,
+// even if multiple targets don't support WriteString.
+func TestMultiWriter_WriteStringSingleAlloc(t *testing.T) {
+ var sink1, sink2 bytes.Buffer
+ type simpleWriter struct { // hide bytes.Buffer's WriteString
+ Writer
+ }
+ mw := MultiWriter(simpleWriter{&sink1}, simpleWriter{&sink2})
+ allocs := int(testing.AllocsPerRun(1000, func() {
+ WriteString(mw, "foo")
+ }))
+ if allocs != 1 {
+ t.Errorf("num allocations = %d; want 1", allocs)
+ }
+}
+
+type writeStringChecker struct{ called bool }
+
+func (c *writeStringChecker) WriteString(s string) (n int, err error) {
+ c.called = true
+ return len(s), nil
+}
+
+func (c *writeStringChecker) Write(p []byte) (n int, err error) {
+ return len(p), nil
+}
+
+func TestMultiWriter_StringCheckCall(t *testing.T) {
+ var c writeStringChecker
+ mw := MultiWriter(&c)
+ WriteString(mw, "foo")
+ if !c.called {
+ t.Error("did not see WriteString call to writeStringChecker")
+ }
+}
+
+func testMultiWriter(t *testing.T, sink interface {
+ Writer
+ fmt.Stringer
+}) {
+ sha1 := sha1.New()
+ mw := MultiWriter(sha1, sink)
+
+ sourceString := "My input text."
+ source := strings.NewReader(sourceString)
+ written, err := Copy(mw, source)
+
+ if written != int64(len(sourceString)) {
+ t.Errorf("short write of %d, not %d", written, len(sourceString))
+ }
+
+ if err != nil {
+ t.Errorf("unexpected error: %v", err)
+ }
+
+ sha1hex := fmt.Sprintf("%x", sha1.Sum(nil))
+ if sha1hex != "01cb303fa8c30a64123067c5aa6284ba7ec2d31b" {
+ t.Error("incorrect sha1 value")
+ }
+
+ if sink.String() != sourceString {
+ t.Errorf("expected %q; got %q", sourceString, sink.String())
+ }
+}
+
+// writerFunc is a Writer implemented by the underlying func.
+type writerFunc func(p []byte) (int, error)
+
+func (f writerFunc) Write(p []byte) (int, error) {
+ return f(p)
+}
+
+// Test that MultiWriter properly flattens chained multiWriters.
+func TestMultiWriterSingleChainFlatten(t *testing.T) {
+ pc := make([]uintptr, 1000) // 1000 should fit the full stack
+ n := runtime.Callers(0, pc)
+ var myDepth = callDepth(pc[:n])
+ var writeDepth int // will contain the depth from which writerFunc.Writer was called
+ var w Writer = MultiWriter(writerFunc(func(p []byte) (int, error) {
+ n := runtime.Callers(1, pc)
+ writeDepth += callDepth(pc[:n])
+ return 0, nil
+ }))
+
+ mw := w
+ // chain a bunch of multiWriters
+ for i := 0; i < 100; i++ {
+ mw = MultiWriter(w)
+ }
+
+ mw = MultiWriter(w, mw, w, mw)
+ mw.Write(nil) // don't care about errors, just want to check the call-depth for Write
+
+ if writeDepth != 4*(myDepth+2) { // 2 should be multiWriter.Write and writerFunc.Write
+ t.Errorf("multiWriter did not flatten chained multiWriters: expected writeDepth %d, got %d",
+ 4*(myDepth+2), writeDepth)
+ }
+}
+
+func TestMultiWriterError(t *testing.T) {
+ f1 := writerFunc(func(p []byte) (int, error) {
+ return len(p) / 2, ErrShortWrite
+ })
+ f2 := writerFunc(func(p []byte) (int, error) {
+ t.Errorf("MultiWriter called f2.Write")
+ return len(p), nil
+ })
+ w := MultiWriter(f1, f2)
+ n, err := w.Write(make([]byte, 100))
+ if n != 50 || err != ErrShortWrite {
+ t.Errorf("Write = %d, %v, want 50, ErrShortWrite", n, err)
+ }
+}
+
+// Test that MultiReader copies the input slice and is insulated from future modification.
+func TestMultiReaderCopy(t *testing.T) {
+ slice := []Reader{strings.NewReader("hello world")}
+ r := MultiReader(slice...)
+ slice[0] = nil
+ data, err := ReadAll(r)
+ if err != nil || string(data) != "hello world" {
+ t.Errorf("ReadAll() = %q, %v, want %q, nil", data, err, "hello world")
+ }
+}
+
+// Test that MultiWriter copies the input slice and is insulated from future modification.
+func TestMultiWriterCopy(t *testing.T) {
+ var buf strings.Builder
+ slice := []Writer{&buf}
+ w := MultiWriter(slice...)
+ slice[0] = nil
+ n, err := w.Write([]byte("hello world"))
+ if err != nil || n != 11 {
+ t.Errorf("Write(`hello world`) = %d, %v, want 11, nil", n, err)
+ }
+ if buf.String() != "hello world" {
+ t.Errorf("buf.String() = %q, want %q", buf.String(), "hello world")
+ }
+}
+
+// readerFunc is a Reader implemented by the underlying func.
+type readerFunc func(p []byte) (int, error)
+
+func (f readerFunc) Read(p []byte) (int, error) {
+ return f(p)
+}
+
+// callDepth returns the logical call depth for the given PCs.
+func callDepth(callers []uintptr) (depth int) {
+ frames := runtime.CallersFrames(callers)
+ more := true
+ for more {
+ _, more = frames.Next()
+ depth++
+ }
+ return
+}
+
+// Test that MultiReader properly flattens chained multiReaders when Read is called
+func TestMultiReaderFlatten(t *testing.T) {
+ pc := make([]uintptr, 1000) // 1000 should fit the full stack
+ n := runtime.Callers(0, pc)
+ var myDepth = callDepth(pc[:n])
+ var readDepth int // will contain the depth from which fakeReader.Read was called
+ var r Reader = MultiReader(readerFunc(func(p []byte) (int, error) {
+ n := runtime.Callers(1, pc)
+ readDepth = callDepth(pc[:n])
+ return 0, errors.New("irrelevant")
+ }))
+
+ // chain a bunch of multiReaders
+ for i := 0; i < 100; i++ {
+ r = MultiReader(r)
+ }
+
+ r.Read(nil) // don't care about errors, just want to check the call-depth for Read
+
+ if readDepth != myDepth+2 { // 2 should be multiReader.Read and fakeReader.Read
+ t.Errorf("multiReader did not flatten chained multiReaders: expected readDepth %d, got %d",
+ myDepth+2, readDepth)
+ }
+}
+
+// byteAndEOFReader is a Reader which reads one byte (the underlying
+// byte) and EOF at once in its Read call.
+type byteAndEOFReader byte
+
+func (b byteAndEOFReader) Read(p []byte) (n int, err error) {
+ if len(p) == 0 {
+ // Read(0 bytes) is useless. We expect no such useless
+ // calls in this test.
+ panic("unexpected call")
+ }
+ p[0] = byte(b)
+ return 1, EOF
+}
+
+// This used to yield bytes forever; issue 16795.
+func TestMultiReaderSingleByteWithEOF(t *testing.T) {
+ got, err := ReadAll(LimitReader(MultiReader(byteAndEOFReader('a'), byteAndEOFReader('b')), 10))
+ if err != nil {
+ t.Fatal(err)
+ }
+ const want = "ab"
+ if string(got) != want {
+ t.Errorf("got %q; want %q", got, want)
+ }
+}
+
+// Test that a reader returning (n, EOF) at the end of a MultiReader
+// chain continues to return EOF on its final read, rather than
+// yielding a (0, EOF).
+func TestMultiReaderFinalEOF(t *testing.T) {
+ r := MultiReader(bytes.NewReader(nil), byteAndEOFReader('a'))
+ buf := make([]byte, 2)
+ n, err := r.Read(buf)
+ if n != 1 || err != EOF {
+ t.Errorf("got %v, %v; want 1, EOF", n, err)
+ }
+}
+
+func TestMultiReaderFreesExhaustedReaders(t *testing.T) {
+ var mr Reader
+ closed := make(chan struct{})
+ // The closure ensures that we don't have a live reference to buf1
+ // on our stack after MultiReader is inlined (Issue 18819). This
+ // is a work around for a limitation in liveness analysis.
+ func() {
+ buf1 := bytes.NewReader([]byte("foo"))
+ buf2 := bytes.NewReader([]byte("bar"))
+ mr = MultiReader(buf1, buf2)
+ runtime.AddCleanup(buf1, func(ch chan struct{}) { close(ch) }, closed)
+ }()
+
+ buf := make([]byte, 4)
+ if n, err := ReadFull(mr, buf); err != nil || string(buf) != "foob" {
+ t.Fatalf(`ReadFull = %d (%q), %v; want 3, "foo", nil`, n, buf[:n], err)
+ }
+
+ runtime.GC()
+ select {
+ case <-closed:
+ case <-time.After(5 * time.Second):
+ t.Fatal("timeout waiting for collection of buf1")
+ }
+
+ if n, err := ReadFull(mr, buf[:2]); err != nil || string(buf[:2]) != "ar" {
+ t.Fatalf(`ReadFull = %d (%q), %v; want 2, "ar", nil`, n, buf[:n], err)
+ }
+}
+
+func TestInterleavedMultiReader(t *testing.T) {
+ r1 := strings.NewReader("123")
+ r2 := strings.NewReader("45678")
+
+ mr1 := MultiReader(r1, r2)
+ mr2 := MultiReader(mr1)
+
+ buf := make([]byte, 4)
+
+ // Have mr2 use mr1's []Readers.
+ // Consume r1 (and clear it for GC to handle) and consume part of r2.
+ n, err := ReadFull(mr2, buf)
+ if got := string(buf[:n]); got != "1234" || err != nil {
+ t.Errorf(`ReadFull(mr2) = (%q, %v), want ("1234", nil)`, got, err)
+ }
+
+ // Consume the rest of r2 via mr1.
+ // This should not panic even though mr2 cleared r1.
+ n, err = ReadFull(mr1, buf)
+ if got := string(buf[:n]); got != "5678" || err != nil {
+ t.Errorf(`ReadFull(mr1) = (%q, %v), want ("5678", nil)`, got, err)
+ }
+}
diff --git a/go/src/io/pipe.go b/go/src/io/pipe.go
new file mode 100644
index 0000000000000000000000000000000000000000..f34cf25e9de5bdf1a4843b39ceccb45cc4d74950
--- /dev/null
+++ b/go/src/io/pipe.go
@@ -0,0 +1,202 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Pipe adapter to connect code expecting an io.Reader
+// with code expecting an io.Writer.
+
+package io
+
+import (
+ "errors"
+ "sync"
+)
+
+// onceError is an object that will only store an error once.
+type onceError struct {
+ sync.Mutex // guards following
+ err error
+}
+
+func (a *onceError) Store(err error) {
+ a.Lock()
+ defer a.Unlock()
+ if a.err != nil {
+ return
+ }
+ a.err = err
+}
+func (a *onceError) Load() error {
+ a.Lock()
+ defer a.Unlock()
+ return a.err
+}
+
+// ErrClosedPipe is the error used for read or write operations on a closed pipe.
+var ErrClosedPipe = errors.New("io: read/write on closed pipe")
+
+// A pipe is the shared pipe structure underlying PipeReader and PipeWriter.
+type pipe struct {
+ wrMu sync.Mutex // Serializes Write operations
+ wrCh chan []byte
+ rdCh chan int
+
+ once sync.Once // Protects closing done
+ done chan struct{}
+ rerr onceError
+ werr onceError
+}
+
+func (p *pipe) read(b []byte) (n int, err error) {
+ select {
+ case <-p.done:
+ return 0, p.readCloseError()
+ default:
+ }
+
+ select {
+ case bw := <-p.wrCh:
+ nr := copy(b, bw)
+ p.rdCh <- nr
+ return nr, nil
+ case <-p.done:
+ return 0, p.readCloseError()
+ }
+}
+
+func (p *pipe) closeRead(err error) error {
+ if err == nil {
+ err = ErrClosedPipe
+ }
+ p.rerr.Store(err)
+ p.once.Do(func() { close(p.done) })
+ return nil
+}
+
+func (p *pipe) write(b []byte) (n int, err error) {
+ select {
+ case <-p.done:
+ return 0, p.writeCloseError()
+ default:
+ p.wrMu.Lock()
+ defer p.wrMu.Unlock()
+ }
+
+ for once := true; once || len(b) > 0; once = false {
+ select {
+ case p.wrCh <- b:
+ nw := <-p.rdCh
+ b = b[nw:]
+ n += nw
+ case <-p.done:
+ return n, p.writeCloseError()
+ }
+ }
+ return n, nil
+}
+
+func (p *pipe) closeWrite(err error) error {
+ if err == nil {
+ err = EOF
+ }
+ p.werr.Store(err)
+ p.once.Do(func() { close(p.done) })
+ return nil
+}
+
+// readCloseError is considered internal to the pipe type.
+func (p *pipe) readCloseError() error {
+ rerr := p.rerr.Load()
+ if werr := p.werr.Load(); rerr == nil && werr != nil {
+ return werr
+ }
+ return ErrClosedPipe
+}
+
+// writeCloseError is considered internal to the pipe type.
+func (p *pipe) writeCloseError() error {
+ werr := p.werr.Load()
+ if rerr := p.rerr.Load(); werr == nil && rerr != nil {
+ return rerr
+ }
+ return ErrClosedPipe
+}
+
+// A PipeReader is the read half of a pipe.
+type PipeReader struct{ pipe }
+
+// Read implements the standard Read interface:
+// it reads data from the pipe, blocking until a writer
+// arrives or the write end is closed.
+// If the write end is closed with an error, that error is
+// returned as err; otherwise err is EOF.
+func (r *PipeReader) Read(data []byte) (n int, err error) {
+ return r.pipe.read(data)
+}
+
+// Close closes the reader; subsequent writes to the
+// write half of the pipe will return the error [ErrClosedPipe].
+func (r *PipeReader) Close() error {
+ return r.CloseWithError(nil)
+}
+
+// CloseWithError closes the reader; subsequent writes
+// to the write half of the pipe will return the error err.
+//
+// CloseWithError never overwrites the previous error if it exists
+// and always returns nil.
+func (r *PipeReader) CloseWithError(err error) error {
+ return r.pipe.closeRead(err)
+}
+
+// A PipeWriter is the write half of a pipe.
+type PipeWriter struct{ r PipeReader }
+
+// Write implements the standard Write interface:
+// it writes data to the pipe, blocking until one or more readers
+// have consumed all the data or the read end is closed.
+// If the read end is closed with an error, that err is
+// returned as err; otherwise err is [ErrClosedPipe].
+func (w *PipeWriter) Write(data []byte) (n int, err error) {
+ return w.r.pipe.write(data)
+}
+
+// Close closes the writer; subsequent reads from the
+// read half of the pipe will return no bytes and EOF.
+func (w *PipeWriter) Close() error {
+ return w.CloseWithError(nil)
+}
+
+// CloseWithError closes the writer; subsequent reads from the
+// read half of the pipe will return no bytes and the error err,
+// or EOF if err is nil.
+//
+// CloseWithError never overwrites the previous error if it exists
+// and always returns nil.
+func (w *PipeWriter) CloseWithError(err error) error {
+ return w.r.pipe.closeWrite(err)
+}
+
+// Pipe creates a synchronous in-memory pipe.
+// It can be used to connect code expecting an [io.Reader]
+// with code expecting an [io.Writer].
+//
+// Reads and Writes on the pipe are matched one to one
+// except when multiple Reads are needed to consume a single Write.
+// That is, each Write to the [PipeWriter] blocks until it has satisfied
+// one or more Reads from the [PipeReader] that fully consume
+// the written data.
+// The data is copied directly from the Write to the corresponding
+// Read (or Reads); there is no internal buffering.
+//
+// It is safe to call Read and Write in parallel with each other or with Close.
+// Parallel calls to Read and parallel calls to Write are also safe:
+// the individual calls will be gated sequentially.
+func Pipe() (*PipeReader, *PipeWriter) {
+ pw := &PipeWriter{r: PipeReader{pipe: pipe{
+ wrCh: make(chan []byte),
+ rdCh: make(chan int),
+ done: make(chan struct{}),
+ }}}
+ return &pw.r, pw
+}
diff --git a/go/src/io/pipe_test.go b/go/src/io/pipe_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..fcf94d52d21bcd4234c3492e6f39910fa2abf582
--- /dev/null
+++ b/go/src/io/pipe_test.go
@@ -0,0 +1,441 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package io_test
+
+import (
+ "bytes"
+ "fmt"
+ . "io"
+ "slices"
+ "strings"
+ "testing"
+ "time"
+)
+
+func checkWrite(t *testing.T, w Writer, data []byte, c chan int) {
+ n, err := w.Write(data)
+ if err != nil {
+ t.Errorf("write: %v", err)
+ }
+ if n != len(data) {
+ t.Errorf("short write: %d != %d", n, len(data))
+ }
+ c <- 0
+}
+
+// Test a single read/write pair.
+func TestPipe1(t *testing.T) {
+ c := make(chan int)
+ r, w := Pipe()
+ var buf = make([]byte, 64)
+ go checkWrite(t, w, []byte("hello, world"), c)
+ n, err := r.Read(buf)
+ if err != nil {
+ t.Errorf("read: %v", err)
+ } else if n != 12 || string(buf[0:12]) != "hello, world" {
+ t.Errorf("bad read: got %q", buf[0:n])
+ }
+ <-c
+ r.Close()
+ w.Close()
+}
+
+func reader(t *testing.T, r Reader, c chan int) {
+ var buf = make([]byte, 64)
+ for {
+ n, err := r.Read(buf)
+ if err == EOF {
+ c <- 0
+ break
+ }
+ if err != nil {
+ t.Errorf("read: %v", err)
+ }
+ c <- n
+ }
+}
+
+// Test a sequence of read/write pairs.
+func TestPipe2(t *testing.T) {
+ c := make(chan int)
+ r, w := Pipe()
+ go reader(t, r, c)
+ var buf = make([]byte, 64)
+ for i := 0; i < 5; i++ {
+ p := buf[0 : 5+i*10]
+ n, err := w.Write(p)
+ if n != len(p) {
+ t.Errorf("wrote %d, got %d", len(p), n)
+ }
+ if err != nil {
+ t.Errorf("write: %v", err)
+ }
+ nn := <-c
+ if nn != n {
+ t.Errorf("wrote %d, read got %d", n, nn)
+ }
+ }
+ w.Close()
+ nn := <-c
+ if nn != 0 {
+ t.Errorf("final read got %d", nn)
+ }
+}
+
+type pipeReturn struct {
+ n int
+ err error
+}
+
+// Test a large write that requires multiple reads to satisfy.
+func writer(w WriteCloser, buf []byte, c chan pipeReturn) {
+ n, err := w.Write(buf)
+ w.Close()
+ c <- pipeReturn{n, err}
+}
+
+func TestPipe3(t *testing.T) {
+ c := make(chan pipeReturn)
+ r, w := Pipe()
+ var wdat = make([]byte, 128)
+ for i := 0; i < len(wdat); i++ {
+ wdat[i] = byte(i)
+ }
+ go writer(w, wdat, c)
+ var rdat = make([]byte, 1024)
+ tot := 0
+ for n := 1; n <= 256; n *= 2 {
+ nn, err := r.Read(rdat[tot : tot+n])
+ if err != nil && err != EOF {
+ t.Fatalf("read: %v", err)
+ }
+
+ // only final two reads should be short - 1 byte, then 0
+ expect := n
+ if n == 128 {
+ expect = 1
+ } else if n == 256 {
+ expect = 0
+ if err != EOF {
+ t.Fatalf("read at end: %v", err)
+ }
+ }
+ if nn != expect {
+ t.Fatalf("read %d, expected %d, got %d", n, expect, nn)
+ }
+ tot += nn
+ }
+ pr := <-c
+ if pr.n != 128 || pr.err != nil {
+ t.Fatalf("write 128: %d, %v", pr.n, pr.err)
+ }
+ if tot != 128 {
+ t.Fatalf("total read %d != 128", tot)
+ }
+ for i := 0; i < 128; i++ {
+ if rdat[i] != byte(i) {
+ t.Fatalf("rdat[%d] = %d", i, rdat[i])
+ }
+ }
+}
+
+// Test read after/before writer close.
+
+type closer interface {
+ CloseWithError(error) error
+ Close() error
+}
+
+type pipeTest struct {
+ async bool
+ err error
+ closeWithError bool
+}
+
+func (p pipeTest) String() string {
+ return fmt.Sprintf("async=%v err=%v closeWithError=%v", p.async, p.err, p.closeWithError)
+}
+
+var pipeTests = []pipeTest{
+ {true, nil, false},
+ {true, nil, true},
+ {true, ErrShortWrite, true},
+ {false, nil, false},
+ {false, nil, true},
+ {false, ErrShortWrite, true},
+}
+
+func delayClose(t *testing.T, cl closer, ch chan int, tt pipeTest) {
+ time.Sleep(1 * time.Millisecond)
+ var err error
+ if tt.closeWithError {
+ err = cl.CloseWithError(tt.err)
+ } else {
+ err = cl.Close()
+ }
+ if err != nil {
+ t.Errorf("delayClose: %v", err)
+ }
+ ch <- 0
+}
+
+func TestPipeReadClose(t *testing.T) {
+ for _, tt := range pipeTests {
+ c := make(chan int, 1)
+ r, w := Pipe()
+ if tt.async {
+ go delayClose(t, w, c, tt)
+ } else {
+ delayClose(t, w, c, tt)
+ }
+ var buf = make([]byte, 64)
+ n, err := r.Read(buf)
+ <-c
+ want := tt.err
+ if want == nil {
+ want = EOF
+ }
+ if err != want {
+ t.Errorf("read from closed pipe: %v want %v", err, want)
+ }
+ if n != 0 {
+ t.Errorf("read on closed pipe returned %d", n)
+ }
+ if err = r.Close(); err != nil {
+ t.Errorf("r.Close: %v", err)
+ }
+ }
+}
+
+// Test close on Read side during Read.
+func TestPipeReadClose2(t *testing.T) {
+ c := make(chan int, 1)
+ r, _ := Pipe()
+ go delayClose(t, r, c, pipeTest{})
+ n, err := r.Read(make([]byte, 64))
+ <-c
+ if n != 0 || err != ErrClosedPipe {
+ t.Errorf("read from closed pipe: %v, %v want %v, %v", n, err, 0, ErrClosedPipe)
+ }
+}
+
+// Test write after/before reader close.
+
+func TestPipeWriteClose(t *testing.T) {
+ for _, tt := range pipeTests {
+ c := make(chan int, 1)
+ r, w := Pipe()
+ if tt.async {
+ go delayClose(t, r, c, tt)
+ } else {
+ delayClose(t, r, c, tt)
+ }
+ n, err := WriteString(w, "hello, world")
+ <-c
+ expect := tt.err
+ if expect == nil {
+ expect = ErrClosedPipe
+ }
+ if err != expect {
+ t.Errorf("write on closed pipe: %v want %v", err, expect)
+ }
+ if n != 0 {
+ t.Errorf("write on closed pipe returned %d", n)
+ }
+ if err = w.Close(); err != nil {
+ t.Errorf("w.Close: %v", err)
+ }
+ }
+}
+
+// Test close on Write side during Write.
+func TestPipeWriteClose2(t *testing.T) {
+ c := make(chan int, 1)
+ _, w := Pipe()
+ go delayClose(t, w, c, pipeTest{})
+ n, err := w.Write(make([]byte, 64))
+ <-c
+ if n != 0 || err != ErrClosedPipe {
+ t.Errorf("write to closed pipe: %v, %v want %v, %v", n, err, 0, ErrClosedPipe)
+ }
+}
+
+func TestWriteEmpty(t *testing.T) {
+ r, w := Pipe()
+ go func() {
+ w.Write([]byte{})
+ w.Close()
+ }()
+ var b [2]byte
+ ReadFull(r, b[0:2])
+ r.Close()
+}
+
+func TestWriteNil(t *testing.T) {
+ r, w := Pipe()
+ go func() {
+ w.Write(nil)
+ w.Close()
+ }()
+ var b [2]byte
+ ReadFull(r, b[0:2])
+ r.Close()
+}
+
+func TestWriteAfterWriterClose(t *testing.T) {
+ r, w := Pipe()
+ defer r.Close()
+ done := make(chan bool)
+ var writeErr error
+ go func() {
+ _, err := w.Write([]byte("hello"))
+ if err != nil {
+ t.Errorf("got error: %q; expected none", err)
+ }
+ w.Close()
+ _, writeErr = w.Write([]byte("world"))
+ done <- true
+ }()
+
+ buf := make([]byte, 100)
+ var result string
+ n, err := ReadFull(r, buf)
+ if err != nil && err != ErrUnexpectedEOF {
+ t.Fatalf("got: %q; want: %q", err, ErrUnexpectedEOF)
+ }
+ result = string(buf[0:n])
+ <-done
+
+ if result != "hello" {
+ t.Errorf("got: %q; want: %q", result, "hello")
+ }
+ if writeErr != ErrClosedPipe {
+ t.Errorf("got: %q; want: %q", writeErr, ErrClosedPipe)
+ }
+}
+
+func TestPipeCloseError(t *testing.T) {
+ type testError1 struct{ error }
+ type testError2 struct{ error }
+
+ r, w := Pipe()
+ r.CloseWithError(testError1{})
+ if _, err := w.Write(nil); err != (testError1{}) {
+ t.Errorf("Write error: got %T, want testError1", err)
+ }
+ r.CloseWithError(testError2{})
+ if _, err := w.Write(nil); err != (testError1{}) {
+ t.Errorf("Write error: got %T, want testError1", err)
+ }
+
+ r, w = Pipe()
+ w.CloseWithError(testError1{})
+ if _, err := r.Read(nil); err != (testError1{}) {
+ t.Errorf("Read error: got %T, want testError1", err)
+ }
+ w.CloseWithError(testError2{})
+ if _, err := r.Read(nil); err != (testError1{}) {
+ t.Errorf("Read error: got %T, want testError1", err)
+ }
+}
+
+func TestPipeConcurrent(t *testing.T) {
+ const (
+ input = "0123456789abcdef"
+ count = 8
+ readSize = 2
+ )
+
+ t.Run("Write", func(t *testing.T) {
+ r, w := Pipe()
+
+ for i := 0; i < count; i++ {
+ go func() {
+ time.Sleep(time.Millisecond) // Increase probability of race
+ if n, err := w.Write([]byte(input)); n != len(input) || err != nil {
+ t.Errorf("Write() = (%d, %v); want (%d, nil)", n, err, len(input))
+ }
+ }()
+ }
+
+ buf := make([]byte, count*len(input))
+ for i := 0; i < len(buf); i += readSize {
+ if n, err := r.Read(buf[i : i+readSize]); n != readSize || err != nil {
+ t.Errorf("Read() = (%d, %v); want (%d, nil)", n, err, readSize)
+ }
+ }
+
+ // Since each Write is fully gated, if multiple Read calls were needed,
+ // the contents of Write should still appear together in the output.
+ got := string(buf)
+ want := strings.Repeat(input, count)
+ if got != want {
+ t.Errorf("got: %q; want: %q", got, want)
+ }
+ })
+
+ t.Run("Read", func(t *testing.T) {
+ r, w := Pipe()
+
+ c := make(chan []byte, count*len(input)/readSize)
+ for i := 0; i < cap(c); i++ {
+ go func() {
+ time.Sleep(time.Millisecond) // Increase probability of race
+ buf := make([]byte, readSize)
+ if n, err := r.Read(buf); n != readSize || err != nil {
+ t.Errorf("Read() = (%d, %v); want (%d, nil)", n, err, readSize)
+ }
+ c <- buf
+ }()
+ }
+
+ for i := 0; i < count; i++ {
+ if n, err := w.Write([]byte(input)); n != len(input) || err != nil {
+ t.Errorf("Write() = (%d, %v); want (%d, nil)", n, err, len(input))
+ }
+ }
+
+ // Since each read is independent, the only guarantee about the output
+ // is that it is a permutation of the input in readSized groups.
+ got := make([]byte, 0, count*len(input))
+ for i := 0; i < cap(c); i++ {
+ got = append(got, (<-c)...)
+ }
+ got = sortBytesInGroups(got, readSize)
+ want := bytes.Repeat([]byte(input), count)
+ want = sortBytesInGroups(want, readSize)
+ if string(got) != string(want) {
+ t.Errorf("got: %q; want: %q", got, want)
+ }
+ })
+}
+
+func sortBytesInGroups(b []byte, n int) []byte {
+ var groups [][]byte
+ for len(b) > 0 {
+ groups = append(groups, b[:n])
+ b = b[n:]
+ }
+ slices.SortFunc(groups, bytes.Compare)
+ return bytes.Join(groups, nil)
+}
+
+var (
+ rSink *PipeReader
+ wSink *PipeWriter
+)
+
+func TestPipeAllocations(t *testing.T) {
+ numAllocs := testing.AllocsPerRun(10, func() {
+ rSink, wSink = Pipe()
+ })
+
+ // go.dev/cl/473535 claimed Pipe() should only do 2 allocations,
+ // plus the 2 escaping to heap for simulating real world usages.
+ expectedAllocs := 4
+ if int(numAllocs) > expectedAllocs {
+ t.Fatalf("too many allocations for io.Pipe() call: %f", numAllocs)
+ }
+}
diff --git a/go/src/iter/iter.go b/go/src/iter/iter.go
new file mode 100644
index 0000000000000000000000000000000000000000..f119eae995199546c2674135aca141e086876ff8
--- /dev/null
+++ b/go/src/iter/iter.go
@@ -0,0 +1,473 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package iter provides basic definitions and operations related to
+iterators over sequences.
+
+# Iterators
+
+An iterator is a function that passes successive elements of a
+sequence to a callback function, conventionally named yield.
+The function stops either when the sequence is finished or
+when yield returns false, indicating to stop the iteration early.
+This package defines [Seq] and [Seq2]
+(pronounced like seek—the first syllable of sequence)
+as shorthands for iterators that pass 1 or 2 values per sequence element
+to yield:
+
+ type (
+ Seq[V any] func(yield func(V) bool)
+ Seq2[K, V any] func(yield func(K, V) bool)
+ )
+
+Seq2 represents a sequence of paired values, conventionally key-value
+or index-value pairs.
+
+Yield returns true if the iterator should continue with the next
+element in the sequence, false if it should stop.
+
+Yield panics if called after it returns false.
+
+For instance, [maps.Keys] returns an iterator that produces the sequence
+of keys of the map m, implemented as follows:
+
+ func Keys[Map ~map[K]V, K comparable, V any](m Map) iter.Seq[K] {
+ return func(yield func(K) bool) {
+ for k := range m {
+ if !yield(k) {
+ return
+ }
+ }
+ }
+ }
+
+Further examples can be found in [The Go Blog: Range Over Function Types].
+
+Iterator functions are most often called by a [range loop], as in:
+
+ func PrintAll[V any](seq iter.Seq[V]) {
+ for v := range seq {
+ fmt.Println(v)
+ }
+ }
+
+# Naming Conventions
+
+Iterator functions and methods are named for the sequence being walked:
+
+ // All returns an iterator over all elements in s.
+ func (s *Set[V]) All() iter.Seq[V]
+
+The iterator method on a collection type is conventionally named All,
+because it iterates a sequence of all the values in the collection.
+
+For a type containing multiple possible sequences, the iterator's name
+can indicate which sequence is being provided:
+
+ // Cities returns an iterator over the major cities in the country.
+ func (c *Country) Cities() iter.Seq[*City]
+
+ // Languages returns an iterator over the official spoken languages of the country.
+ func (c *Country) Languages() iter.Seq[string]
+
+If an iterator requires additional configuration, the constructor function
+can take additional configuration arguments:
+
+ // Scan returns an iterator over key-value pairs with min ≤ key ≤ max.
+ func (m *Map[K, V]) Scan(min, max K) iter.Seq2[K, V]
+
+ // Split returns an iterator over the (possibly-empty) substrings of s
+ // separated by sep.
+ func Split(s, sep string) iter.Seq[string]
+
+When there are multiple possible iteration orders, the method name may
+indicate that order:
+
+ // All returns an iterator over the list from head to tail.
+ func (l *List[V]) All() iter.Seq[V]
+
+ // Backward returns an iterator over the list from tail to head.
+ func (l *List[V]) Backward() iter.Seq[V]
+
+ // Preorder returns an iterator over all nodes of the syntax tree
+ // beneath (and including) the specified root, in depth-first preorder,
+ // visiting a parent node before its children.
+ func Preorder(root Node) iter.Seq[Node]
+
+# Single-Use Iterators
+
+Most iterators provide the ability to walk an entire sequence:
+when called, the iterator does any setup necessary to start the
+sequence, then calls yield on successive elements of the sequence,
+and then cleans up before returning. Calling the iterator again
+walks the sequence again.
+
+Some iterators break that convention, providing the ability to walk a
+sequence only once. These “single-use iterators” typically report values
+from a data stream that cannot be rewound to start over.
+Calling the iterator again after stopping early may continue the
+stream, but calling it again after the sequence is finished will yield
+no values at all. Doc comments for functions or methods that return
+single-use iterators should document this fact:
+
+ // Lines returns an iterator over lines read from r.
+ // It returns a single-use iterator.
+ func (r *Reader) Lines() iter.Seq[string]
+
+# Pulling Values
+
+Functions and methods that accept or return iterators
+should use the standard [Seq] or [Seq2] types, to ensure
+compatibility with range loops and other iterator adapters.
+The standard iterators can be thought of as “push iterators”, which
+push values to the yield function.
+
+Sometimes a range loop is not the most natural way to consume values
+of the sequence. In this case, [Pull] converts a standard push iterator
+to a “pull iterator”, which can be called to pull one value at a time
+from the sequence. [Pull] starts an iterator and returns a pair
+of functions—next and stop—which return the next value from the iterator
+and stop it, respectively.
+
+For example:
+
+ // Pairs returns an iterator over successive pairs of values from seq.
+ func Pairs[V any](seq iter.Seq[V]) iter.Seq2[V, V] {
+ return func(yield func(V, V) bool) {
+ next, stop := iter.Pull(seq)
+ defer stop()
+ for {
+ v1, ok1 := next()
+ if !ok1 {
+ return
+ }
+ v2, ok2 := next()
+ // If ok2 is false, v2 should be the
+ // zero value; yield one last pair.
+ if !yield(v1, v2) {
+ return
+ }
+ if !ok2 {
+ return
+ }
+ }
+ }
+ }
+
+If clients do not consume the sequence to completion, they must call stop,
+which allows the iterator function to finish and return. As shown in
+the example, the conventional way to ensure this is to use defer.
+
+# Standard Library Usage
+
+A few packages in the standard library provide iterator-based APIs,
+most notably the [maps] and [slices] packages.
+For example, [maps.Keys] returns an iterator over the keys of a map,
+while [slices.Sorted] collects the values of an iterator into a slice,
+sorts them, and returns the slice, so to iterate over the sorted keys of a map:
+
+ for _, key := range slices.Sorted(maps.Keys(m)) {
+ ...
+ }
+
+# Mutation
+
+Iterators provide only the values of the sequence, not any direct way
+to modify it. If an iterator wishes to provide a mechanism for modifying
+a sequence during iteration, the usual approach is to define a position type
+with the extra operations and then provide an iterator over positions.
+
+For example, a tree implementation might provide:
+
+ // Positions returns an iterator over positions in the sequence.
+ func (t *Tree[V]) Positions() iter.Seq[*Pos[V]]
+
+ // A Pos represents a position in the sequence.
+ // It is only valid during the yield call it is passed to.
+ type Pos[V any] struct { ... }
+
+ // Value returns the value at the cursor.
+ func (p *Pos[V]) Value() V
+
+ // Delete deletes the value at this point in the iteration.
+ func (p *Pos[V]) Delete()
+
+ // Set changes the value v at the cursor.
+ func (p *Pos[V]) Set(v V)
+
+And then a client could delete boring values from the tree using:
+
+ for p := range t.Positions() {
+ if boring(p.Value()) {
+ p.Delete()
+ }
+ }
+
+[The Go Blog: Range Over Function Types]: https://go.dev/blog/range-functions
+[range loop]: https://go.dev/ref/spec#For_range
+*/
+package iter
+
+import (
+ "internal/race"
+ "runtime"
+ "unsafe"
+)
+
+// Seq is an iterator over sequences of individual values.
+// When called as seq(yield), seq calls yield(v) for each value v in the sequence,
+// stopping early if yield returns false.
+// See the [iter] package documentation for more details.
+type Seq[V any] func(yield func(V) bool)
+
+// Seq2 is an iterator over sequences of pairs of values, most commonly key-value pairs.
+// When called as seq(yield), seq calls yield(k, v) for each pair (k, v) in the sequence,
+// stopping early if yield returns false.
+// See the [iter] package documentation for more details.
+type Seq2[K, V any] func(yield func(K, V) bool)
+
+type coro struct{}
+
+//go:linkname newcoro runtime.newcoro
+func newcoro(func(*coro)) *coro
+
+//go:linkname coroswitch runtime.coroswitch
+func coroswitch(*coro)
+
+// Pull converts the “push-style” iterator sequence seq
+// into a “pull-style” iterator accessed by the two functions
+// next and stop.
+//
+// Next returns the next value in the sequence
+// and a boolean indicating whether the value is valid.
+// When the sequence is over, next returns the zero V and false.
+// It is valid to call next after reaching the end of the sequence
+// or after calling stop. These calls will continue
+// to return the zero V and false.
+//
+// Stop ends the iteration. It must be called when the caller is
+// no longer interested in next values and next has not yet
+// signaled that the sequence is over (with a false boolean return).
+// It is valid to call stop multiple times and when next has
+// already returned false. Typically, callers should “defer stop()”.
+//
+// It is an error to call next or stop from multiple goroutines
+// simultaneously.
+//
+// If the iterator panics during a call to next (or stop),
+// then next (or stop) itself panics with the same value.
+func Pull[V any](seq Seq[V]) (next func() (V, bool), stop func()) {
+ var pull struct {
+ v V
+ ok bool
+ done bool
+ yieldNext bool
+ seqDone bool // to detect Goexit
+ racer int
+ panicValue any
+ }
+ c := newcoro(func(c *coro) {
+ race.Acquire(unsafe.Pointer(&pull.racer))
+ if pull.done {
+ race.Release(unsafe.Pointer(&pull.racer))
+ return
+ }
+ yield := func(v1 V) bool {
+ if pull.done {
+ return false
+ }
+ if !pull.yieldNext {
+ panic("iter.Pull: yield called again before next")
+ }
+ pull.yieldNext = false
+ pull.v, pull.ok = v1, true
+ race.Release(unsafe.Pointer(&pull.racer))
+ coroswitch(c)
+ race.Acquire(unsafe.Pointer(&pull.racer))
+ return !pull.done
+ }
+ // Recover and propagate panics from seq.
+ defer func() {
+ if p := recover(); p != nil {
+ pull.panicValue = p
+ } else if !pull.seqDone {
+ pull.panicValue = goexitPanicValue
+ }
+ pull.done = true // Invalidate iterator
+ race.Release(unsafe.Pointer(&pull.racer))
+ }()
+ seq(yield)
+ var v0 V
+ pull.v, pull.ok = v0, false
+ pull.seqDone = true
+ })
+ next = func() (v1 V, ok1 bool) {
+ race.Write(unsafe.Pointer(&pull.racer)) // detect races
+
+ if pull.done {
+ return
+ }
+ if pull.yieldNext {
+ panic("iter.Pull: next called again before yield")
+ }
+ pull.yieldNext = true
+ race.Release(unsafe.Pointer(&pull.racer))
+ coroswitch(c)
+ race.Acquire(unsafe.Pointer(&pull.racer))
+
+ // Propagate panics and goexits from seq.
+ if pull.panicValue != nil {
+ if pull.panicValue == goexitPanicValue {
+ // Propagate runtime.Goexit from seq.
+ runtime.Goexit()
+ } else {
+ panic(pull.panicValue)
+ }
+ }
+ return pull.v, pull.ok
+ }
+ stop = func() {
+ race.Write(unsafe.Pointer(&pull.racer)) // detect races
+
+ if !pull.done {
+ pull.done = true
+ race.Release(unsafe.Pointer(&pull.racer))
+ coroswitch(c)
+ race.Acquire(unsafe.Pointer(&pull.racer))
+
+ // Propagate panics and goexits from seq.
+ if pull.panicValue != nil {
+ if pull.panicValue == goexitPanicValue {
+ // Propagate runtime.Goexit from seq.
+ runtime.Goexit()
+ } else {
+ panic(pull.panicValue)
+ }
+ }
+ }
+ }
+ return next, stop
+}
+
+// Pull2 converts the “push-style” iterator sequence seq
+// into a “pull-style” iterator accessed by the two functions
+// next and stop.
+//
+// Next returns the next pair in the sequence
+// and a boolean indicating whether the pair is valid.
+// When the sequence is over, next returns a pair of zero values and false.
+// It is valid to call next after reaching the end of the sequence
+// or after calling stop. These calls will continue
+// to return a pair of zero values and false.
+//
+// Stop ends the iteration. It must be called when the caller is
+// no longer interested in next values and next has not yet
+// signaled that the sequence is over (with a false boolean return).
+// It is valid to call stop multiple times and when next has
+// already returned false. Typically, callers should “defer stop()”.
+//
+// It is an error to call next or stop from multiple goroutines
+// simultaneously.
+//
+// If the iterator panics during a call to next (or stop),
+// then next (or stop) itself panics with the same value.
+func Pull2[K, V any](seq Seq2[K, V]) (next func() (K, V, bool), stop func()) {
+ var pull struct {
+ k K
+ v V
+ ok bool
+ done bool
+ yieldNext bool
+ seqDone bool
+ racer int
+ panicValue any
+ }
+ c := newcoro(func(c *coro) {
+ race.Acquire(unsafe.Pointer(&pull.racer))
+ if pull.done {
+ race.Release(unsafe.Pointer(&pull.racer))
+ return
+ }
+ yield := func(k1 K, v1 V) bool {
+ if pull.done {
+ return false
+ }
+ if !pull.yieldNext {
+ panic("iter.Pull2: yield called again before next")
+ }
+ pull.yieldNext = false
+ pull.k, pull.v, pull.ok = k1, v1, true
+ race.Release(unsafe.Pointer(&pull.racer))
+ coroswitch(c)
+ race.Acquire(unsafe.Pointer(&pull.racer))
+ return !pull.done
+ }
+ // Recover and propagate panics from seq.
+ defer func() {
+ if p := recover(); p != nil {
+ pull.panicValue = p
+ } else if !pull.seqDone {
+ pull.panicValue = goexitPanicValue
+ }
+ pull.done = true // Invalidate iterator.
+ race.Release(unsafe.Pointer(&pull.racer))
+ }()
+ seq(yield)
+ var k0 K
+ var v0 V
+ pull.k, pull.v, pull.ok = k0, v0, false
+ pull.seqDone = true
+ })
+ next = func() (k1 K, v1 V, ok1 bool) {
+ race.Write(unsafe.Pointer(&pull.racer)) // detect races
+
+ if pull.done {
+ return
+ }
+ if pull.yieldNext {
+ panic("iter.Pull2: next called again before yield")
+ }
+ pull.yieldNext = true
+ race.Release(unsafe.Pointer(&pull.racer))
+ coroswitch(c)
+ race.Acquire(unsafe.Pointer(&pull.racer))
+
+ // Propagate panics and goexits from seq.
+ if pull.panicValue != nil {
+ if pull.panicValue == goexitPanicValue {
+ // Propagate runtime.Goexit from seq.
+ runtime.Goexit()
+ } else {
+ panic(pull.panicValue)
+ }
+ }
+ return pull.k, pull.v, pull.ok
+ }
+ stop = func() {
+ race.Write(unsafe.Pointer(&pull.racer)) // detect races
+
+ if !pull.done {
+ pull.done = true
+ race.Release(unsafe.Pointer(&pull.racer))
+ coroswitch(c)
+ race.Acquire(unsafe.Pointer(&pull.racer))
+
+ // Propagate panics and goexits from seq.
+ if pull.panicValue != nil {
+ if pull.panicValue == goexitPanicValue {
+ // Propagate runtime.Goexit from seq.
+ runtime.Goexit()
+ } else {
+ panic(pull.panicValue)
+ }
+ }
+ }
+ }
+ return next, stop
+}
+
+// goexitPanicValue is a sentinel value indicating that an iterator
+// exited via runtime.Goexit.
+var goexitPanicValue any = new(int)
diff --git a/go/src/iter/pull_test.go b/go/src/iter/pull_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..c66e20897bd8af05596c08448e8214bad7c64407
--- /dev/null
+++ b/go/src/iter/pull_test.go
@@ -0,0 +1,509 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package iter_test
+
+import (
+ "fmt"
+ . "iter"
+ "runtime"
+ "testing"
+)
+
+func count(n int) Seq[int] {
+ return func(yield func(int) bool) {
+ for i := range n {
+ if !yield(i) {
+ break
+ }
+ }
+ }
+}
+
+func squares(n int) Seq2[int, int64] {
+ return func(yield func(int, int64) bool) {
+ for i := range n {
+ if !yield(i, int64(i)*int64(i)) {
+ break
+ }
+ }
+ }
+}
+
+func TestPull(t *testing.T) {
+ for end := 0; end <= 3; end++ {
+ t.Run(fmt.Sprint(end), func(t *testing.T) {
+ ng := stableNumGoroutine()
+ wantNG := func(want int) {
+ if xg := runtime.NumGoroutine() - ng; xg != want {
+ t.Helper()
+ t.Errorf("have %d extra goroutines, want %d", xg, want)
+ }
+ }
+ wantNG(0)
+ next, stop := Pull(count(3))
+ wantNG(1)
+ for i := range end {
+ v, ok := next()
+ if v != i || ok != true {
+ t.Fatalf("next() = %d, %v, want %d, %v", v, ok, i, true)
+ }
+ wantNG(1)
+ }
+ wantNG(1)
+ if end < 3 {
+ stop()
+ wantNG(0)
+ }
+ for range 2 {
+ v, ok := next()
+ if v != 0 || ok != false {
+ t.Fatalf("next() = %d, %v, want %d, %v", v, ok, 0, false)
+ }
+ wantNG(0)
+ }
+ wantNG(0)
+
+ stop()
+ stop()
+ stop()
+ wantNG(0)
+ })
+ }
+}
+
+func TestPull2(t *testing.T) {
+ for end := 0; end <= 3; end++ {
+ t.Run(fmt.Sprint(end), func(t *testing.T) {
+ ng := stableNumGoroutine()
+ wantNG := func(want int) {
+ if xg := runtime.NumGoroutine() - ng; xg != want {
+ t.Helper()
+ t.Errorf("have %d extra goroutines, want %d", xg, want)
+ }
+ }
+ wantNG(0)
+ next, stop := Pull2(squares(3))
+ wantNG(1)
+ for i := range end {
+ k, v, ok := next()
+ if k != i || v != int64(i*i) || ok != true {
+ t.Fatalf("next() = %d, %d, %v, want %d, %d, %v", k, v, ok, i, i*i, true)
+ }
+ wantNG(1)
+ }
+ wantNG(1)
+ if end < 3 {
+ stop()
+ wantNG(0)
+ }
+ for range 2 {
+ k, v, ok := next()
+ if v != 0 || ok != false {
+ t.Fatalf("next() = %d, %d, %v, want %d, %d, %v", k, v, ok, 0, 0, false)
+ }
+ wantNG(0)
+ }
+ wantNG(0)
+
+ stop()
+ stop()
+ stop()
+ wantNG(0)
+ })
+ }
+}
+
+// stableNumGoroutine is like NumGoroutine but tries to ensure stability of
+// the value by letting any exiting goroutines finish exiting.
+func stableNumGoroutine() int {
+ // The idea behind stablizing the value of NumGoroutine is to
+ // see the same value enough times in a row in between calls to
+ // runtime.Gosched. With GOMAXPROCS=1, we're trying to make sure
+ // that other goroutines run, so that they reach a stable point.
+ // It's not guaranteed, because it is still possible for a goroutine
+ // to Gosched back into itself, so we require NumGoroutine to be
+ // the same 100 times in a row. This should be more than enough to
+ // ensure all goroutines get a chance to run to completion (or to
+ // some block point) for a small group of test goroutines.
+ defer runtime.GOMAXPROCS(runtime.GOMAXPROCS(1))
+
+ c := 0
+ ng := runtime.NumGoroutine()
+ for i := 0; i < 1000; i++ {
+ nng := runtime.NumGoroutine()
+ if nng == ng {
+ c++
+ } else {
+ c = 0
+ ng = nng
+ }
+ if c >= 100 {
+ // The same value 100 times in a row is good enough.
+ return ng
+ }
+ runtime.Gosched()
+ }
+ panic("failed to stabilize NumGoroutine after 1000 iterations")
+}
+
+func TestPullDoubleNext(t *testing.T) {
+ next, _ := Pull(doDoubleNext())
+ nextSlot = next
+ next()
+ if nextSlot != nil {
+ t.Fatal("double next did not fail")
+ }
+}
+
+var nextSlot func() (int, bool)
+
+func doDoubleNext() Seq[int] {
+ return func(_ func(int) bool) {
+ defer func() {
+ if recover() != nil {
+ nextSlot = nil
+ }
+ }()
+ nextSlot()
+ }
+}
+
+func TestPullDoubleNext2(t *testing.T) {
+ next, _ := Pull2(doDoubleNext2())
+ nextSlot2 = next
+ next()
+ if nextSlot2 != nil {
+ t.Fatal("double next did not fail")
+ }
+}
+
+var nextSlot2 func() (int, int, bool)
+
+func doDoubleNext2() Seq2[int, int] {
+ return func(_ func(int, int) bool) {
+ defer func() {
+ if recover() != nil {
+ nextSlot2 = nil
+ }
+ }()
+ nextSlot2()
+ }
+}
+
+func TestPullDoubleYield(t *testing.T) {
+ next, stop := Pull(storeYield())
+ next()
+ if yieldSlot == nil {
+ t.Fatal("yield failed")
+ }
+ defer func() {
+ if recover() != nil {
+ yieldSlot = nil
+ }
+ stop()
+ }()
+ yieldSlot(5)
+ if yieldSlot != nil {
+ t.Fatal("double yield did not fail")
+ }
+}
+
+func storeYield() Seq[int] {
+ return func(yield func(int) bool) {
+ yieldSlot = yield
+ if !yield(5) {
+ return
+ }
+ }
+}
+
+var yieldSlot func(int) bool
+
+func TestPullDoubleYield2(t *testing.T) {
+ next, stop := Pull2(storeYield2())
+ next()
+ if yieldSlot2 == nil {
+ t.Fatal("yield failed")
+ }
+ defer func() {
+ if recover() != nil {
+ yieldSlot2 = nil
+ }
+ stop()
+ }()
+ yieldSlot2(23, 77)
+ if yieldSlot2 != nil {
+ t.Fatal("double yield did not fail")
+ }
+}
+
+func storeYield2() Seq2[int, int] {
+ return func(yield func(int, int) bool) {
+ yieldSlot2 = yield
+ if !yield(23, 77) {
+ return
+ }
+ }
+}
+
+var yieldSlot2 func(int, int) bool
+
+func TestPullPanic(t *testing.T) {
+ t.Run("next", func(t *testing.T) {
+ next, stop := Pull(panicSeq())
+ if !panicsWith("boom", func() { next() }) {
+ t.Fatal("failed to propagate panic on first next")
+ }
+ // Make sure we don't panic again if we try to call next or stop.
+ if _, ok := next(); ok {
+ t.Fatal("next returned true after iterator panicked")
+ }
+ // Calling stop again should be a no-op.
+ stop()
+ })
+ t.Run("stop", func(t *testing.T) {
+ next, stop := Pull(panicCleanupSeq())
+ x, ok := next()
+ if !ok || x != 55 {
+ t.Fatalf("expected (55, true) from next, got (%d, %t)", x, ok)
+ }
+ if !panicsWith("boom", func() { stop() }) {
+ t.Fatal("failed to propagate panic on stop")
+ }
+ // Make sure we don't panic again if we try to call next or stop.
+ if _, ok := next(); ok {
+ t.Fatal("next returned true after iterator panicked")
+ }
+ // Calling stop again should be a no-op.
+ stop()
+ })
+}
+
+func panicSeq() Seq[int] {
+ return func(yield func(int) bool) {
+ panic("boom")
+ }
+}
+
+func panicCleanupSeq() Seq[int] {
+ return func(yield func(int) bool) {
+ for {
+ if !yield(55) {
+ panic("boom")
+ }
+ }
+ }
+}
+
+func TestPull2Panic(t *testing.T) {
+ t.Run("next", func(t *testing.T) {
+ next, stop := Pull2(panicSeq2())
+ if !panicsWith("boom", func() { next() }) {
+ t.Fatal("failed to propagate panic on first next")
+ }
+ // Make sure we don't panic again if we try to call next or stop.
+ if _, _, ok := next(); ok {
+ t.Fatal("next returned true after iterator panicked")
+ }
+ // Calling stop again should be a no-op.
+ stop()
+ })
+ t.Run("stop", func(t *testing.T) {
+ next, stop := Pull2(panicCleanupSeq2())
+ x, y, ok := next()
+ if !ok || x != 55 || y != 100 {
+ t.Fatalf("expected (55, 100, true) from next, got (%d, %d, %t)", x, y, ok)
+ }
+ if !panicsWith("boom", func() { stop() }) {
+ t.Fatal("failed to propagate panic on stop")
+ }
+ // Make sure we don't panic again if we try to call next or stop.
+ if _, _, ok := next(); ok {
+ t.Fatal("next returned true after iterator panicked")
+ }
+ // Calling stop again should be a no-op.
+ stop()
+ })
+}
+
+func panicSeq2() Seq2[int, int] {
+ return func(yield func(int, int) bool) {
+ panic("boom")
+ }
+}
+
+func panicCleanupSeq2() Seq2[int, int] {
+ return func(yield func(int, int) bool) {
+ for {
+ if !yield(55, 100) {
+ panic("boom")
+ }
+ }
+ }
+}
+
+func panicsWith(v any, f func()) (panicked bool) {
+ defer func() {
+ if r := recover(); r != nil {
+ if r != v {
+ panic(r)
+ }
+ panicked = true
+ }
+ }()
+ f()
+ return
+}
+
+func TestPullGoexit(t *testing.T) {
+ t.Run("next", func(t *testing.T) {
+ var next func() (int, bool)
+ var stop func()
+ if !goexits(t, func() {
+ next, stop = Pull(goexitSeq())
+ next()
+ }) {
+ t.Fatal("failed to Goexit from next")
+ }
+ if x, ok := next(); x != 0 || ok {
+ t.Fatal("iterator returned valid value after iterator Goexited")
+ }
+ stop()
+ })
+ t.Run("stop", func(t *testing.T) {
+ next, stop := Pull(goexitCleanupSeq())
+ x, ok := next()
+ if !ok || x != 55 {
+ t.Fatalf("expected (55, true) from next, got (%d, %t)", x, ok)
+ }
+ if !goexits(t, func() {
+ stop()
+ }) {
+ t.Fatal("failed to Goexit from stop")
+ }
+ // Make sure we don't panic again if we try to call next or stop.
+ if x, ok := next(); x != 0 || ok {
+ t.Fatal("next returned true or non-zero value after iterator Goexited")
+ }
+ // Calling stop again should be a no-op.
+ stop()
+ })
+}
+
+func goexitSeq() Seq[int] {
+ return func(yield func(int) bool) {
+ runtime.Goexit()
+ }
+}
+
+func goexitCleanupSeq() Seq[int] {
+ return func(yield func(int) bool) {
+ for {
+ if !yield(55) {
+ runtime.Goexit()
+ }
+ }
+ }
+}
+
+func TestPull2Goexit(t *testing.T) {
+ t.Run("next", func(t *testing.T) {
+ var next func() (int, int, bool)
+ var stop func()
+ if !goexits(t, func() {
+ next, stop = Pull2(goexitSeq2())
+ next()
+ }) {
+ t.Fatal("failed to Goexit from next")
+ }
+ if x, y, ok := next(); x != 0 || y != 0 || ok {
+ t.Fatal("iterator returned valid value after iterator Goexited")
+ }
+ stop()
+ })
+ t.Run("stop", func(t *testing.T) {
+ next, stop := Pull2(goexitCleanupSeq2())
+ x, y, ok := next()
+ if !ok || x != 55 || y != 100 {
+ t.Fatalf("expected (55, 100, true) from next, got (%d, %d, %t)", x, y, ok)
+ }
+ if !goexits(t, func() {
+ stop()
+ }) {
+ t.Fatal("failed to Goexit from stop")
+ }
+ // Make sure we don't panic again if we try to call next or stop.
+ if x, y, ok := next(); x != 0 || y != 0 || ok {
+ t.Fatal("next returned true or non-zero after iterator Goexited")
+ }
+ // Calling stop again should be a no-op.
+ stop()
+ })
+}
+
+func goexitSeq2() Seq2[int, int] {
+ return func(yield func(int, int) bool) {
+ runtime.Goexit()
+ }
+}
+
+func goexitCleanupSeq2() Seq2[int, int] {
+ return func(yield func(int, int) bool) {
+ for {
+ if !yield(55, 100) {
+ runtime.Goexit()
+ }
+ }
+ }
+}
+
+func goexits(t *testing.T, f func()) bool {
+ t.Helper()
+
+ exit := make(chan bool)
+ go func() {
+ cleanExit := false
+ defer func() {
+ exit <- recover() == nil && !cleanExit
+ }()
+ f()
+ cleanExit = true
+ }()
+ return <-exit
+}
+
+func TestPullImmediateStop(t *testing.T) {
+ next, stop := Pull(panicSeq())
+ stop()
+ // Make sure we don't panic if we try to call next or stop.
+ if _, ok := next(); ok {
+ t.Fatal("next returned true after iterator was stopped")
+ }
+}
+
+func TestPull2ImmediateStop(t *testing.T) {
+ next, stop := Pull2(panicSeq2())
+ stop()
+ // Make sure we don't panic if we try to call next or stop.
+ if _, _, ok := next(); ok {
+ t.Fatal("next returned true after iterator was stopped")
+ }
+}
+
+func BenchmarkPull(b *testing.B) {
+ seq := count(1)
+ for range b.N {
+ _, stop := Pull(seq)
+ stop()
+ }
+}
+
+func BenchmarkPull2(b *testing.B) {
+ seq := squares(1)
+ for range b.N {
+ _, stop := Pull2(seq)
+ stop()
+ }
+}
diff --git a/go/src/log/example_test.go b/go/src/log/example_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..769d076e9d59870bc93cacee20dd5e57d08ebd70
--- /dev/null
+++ b/go/src/log/example_test.go
@@ -0,0 +1,41 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package log_test
+
+import (
+ "bytes"
+ "fmt"
+ "log"
+)
+
+func ExampleLogger() {
+ var (
+ buf bytes.Buffer
+ logger = log.New(&buf, "logger: ", log.Lshortfile)
+ )
+
+ logger.Print("Hello, log file!")
+
+ fmt.Print(&buf)
+ // Output:
+ // logger: example_test.go:19: Hello, log file!
+}
+
+func ExampleLogger_Output() {
+ var (
+ buf bytes.Buffer
+ logger = log.New(&buf, "INFO: ", log.Lshortfile)
+
+ infof = func(info string) {
+ logger.Output(2, info)
+ }
+ )
+
+ infof("Hello world")
+
+ fmt.Print(&buf)
+ // Output:
+ // INFO: example_test.go:36: Hello world
+}
diff --git a/go/src/log/log.go b/go/src/log/log.go
new file mode 100644
index 0000000000000000000000000000000000000000..c79b3a9b7428db49387fbde49017194541f8dd18
--- /dev/null
+++ b/go/src/log/log.go
@@ -0,0 +1,483 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package log implements a simple logging package. It defines a type, [Logger],
+// with methods for formatting output. It also has a predefined 'standard'
+// Logger accessible through helper functions Print[f|ln], Fatal[f|ln], and
+// Panic[f|ln], which are easier to use than creating a Logger manually.
+// That logger writes to standard error and prints the date and time
+// of each logged message.
+// Every log message is output on a separate line: if the message being
+// printed does not end in a newline, the logger will add one.
+// The Fatal functions call [os.Exit](1) after writing the log message.
+// The Panic functions call panic after writing the log message.
+package log
+
+import (
+ "fmt"
+ "io"
+ "log/internal"
+ "os"
+ "runtime"
+ "sync"
+ "sync/atomic"
+ "time"
+)
+
+// These flags define which text to prefix to each log entry generated by the [Logger].
+// Bits are or'ed together to control what's printed.
+// With the exception of the Lmsgprefix flag, there is no
+// control over the order they appear (the order listed here)
+// or the format they present (as described in the comments).
+// The prefix is followed by a colon only when Llongfile or Lshortfile
+// is specified.
+// For example, flags Ldate | Ltime (or LstdFlags) produce,
+//
+// 2009/01/23 01:23:23 message
+//
+// while flags Ldate | Ltime | Lmicroseconds | Llongfile produce,
+//
+// 2009/01/23 01:23:23.123123 /a/b/c/d.go:23: message
+const (
+ Ldate = 1 << iota // the date in the local time zone: 2009/01/23
+ Ltime // the time in the local time zone: 01:23:23
+ Lmicroseconds // microsecond resolution: 01:23:23.123123. assumes Ltime.
+ Llongfile // full file name and line number: /a/b/c/d.go:23
+ Lshortfile // final file name element and line number: d.go:23. overrides Llongfile
+ LUTC // if Ldate or Ltime is set, use UTC rather than the local time zone
+ Lmsgprefix // move the "prefix" from the beginning of the line to before the message
+ LstdFlags = Ldate | Ltime // initial values for the standard logger
+)
+
+// A Logger represents an active logging object that generates lines of
+// output to an [io.Writer]. Each logging operation makes a single call to
+// the Writer's Write method. A Logger can be used simultaneously from
+// multiple goroutines; it guarantees to serialize access to the Writer.
+type Logger struct {
+ outMu sync.Mutex
+ out io.Writer // destination for output
+
+ prefix atomic.Pointer[string] // prefix on each line to identify the logger (but see Lmsgprefix)
+ flag atomic.Int32 // properties
+ isDiscard atomic.Bool
+}
+
+// New creates a new [Logger]. The out variable sets the
+// destination to which log data will be written.
+// The prefix appears at the beginning of each generated log line, or
+// after the log header if the [Lmsgprefix] flag is provided.
+// The flag argument defines the logging properties.
+func New(out io.Writer, prefix string, flag int) *Logger {
+ l := new(Logger)
+ l.SetOutput(out)
+ l.SetPrefix(prefix)
+ l.SetFlags(flag)
+ return l
+}
+
+// SetOutput sets the output destination for the logger.
+func (l *Logger) SetOutput(w io.Writer) {
+ l.outMu.Lock()
+ defer l.outMu.Unlock()
+ l.out = w
+ l.isDiscard.Store(w == io.Discard)
+}
+
+var std = New(os.Stderr, "", LstdFlags)
+
+// Default returns the standard logger used by the package-level output functions.
+func Default() *Logger { return std }
+
+// Cheap integer to fixed-width decimal ASCII. Give a negative width to avoid zero-padding.
+func itoa(buf *[]byte, i int, wid int) {
+ // Assemble decimal in reverse order.
+ var b [20]byte
+ bp := len(b) - 1
+ for i >= 10 || wid > 1 {
+ wid--
+ q := i / 10
+ b[bp] = byte('0' + i - q*10)
+ bp--
+ i = q
+ }
+ // i < 10
+ b[bp] = byte('0' + i)
+ *buf = append(*buf, b[bp:]...)
+}
+
+// formatHeader writes log header to buf in following order:
+// - l.prefix (if it's not blank and Lmsgprefix is unset),
+// - date and/or time (if corresponding flags are provided),
+// - file and line number (if corresponding flags are provided),
+// - l.prefix (if it's not blank and Lmsgprefix is set).
+func formatHeader(buf *[]byte, t time.Time, prefix string, flag int, file string, line int) {
+ if flag&Lmsgprefix == 0 {
+ *buf = append(*buf, prefix...)
+ }
+ if flag&(Ldate|Ltime|Lmicroseconds) != 0 {
+ if flag&LUTC != 0 {
+ t = t.UTC()
+ }
+ if flag&Ldate != 0 {
+ year, month, day := t.Date()
+ itoa(buf, year, 4)
+ *buf = append(*buf, '/')
+ itoa(buf, int(month), 2)
+ *buf = append(*buf, '/')
+ itoa(buf, day, 2)
+ *buf = append(*buf, ' ')
+ }
+ if flag&(Ltime|Lmicroseconds) != 0 {
+ hour, min, sec := t.Clock()
+ itoa(buf, hour, 2)
+ *buf = append(*buf, ':')
+ itoa(buf, min, 2)
+ *buf = append(*buf, ':')
+ itoa(buf, sec, 2)
+ if flag&Lmicroseconds != 0 {
+ *buf = append(*buf, '.')
+ itoa(buf, t.Nanosecond()/1e3, 6)
+ }
+ *buf = append(*buf, ' ')
+ }
+ }
+ if flag&(Lshortfile|Llongfile) != 0 {
+ if flag&Lshortfile != 0 {
+ short := file
+ for i := len(file) - 1; i > 0; i-- {
+ if file[i] == '/' {
+ short = file[i+1:]
+ break
+ }
+ }
+ file = short
+ }
+ *buf = append(*buf, file...)
+ *buf = append(*buf, ':')
+ itoa(buf, line, -1)
+ *buf = append(*buf, ": "...)
+ }
+ if flag&Lmsgprefix != 0 {
+ *buf = append(*buf, prefix...)
+ }
+}
+
+var bufferPool = sync.Pool{New: func() any { return new([]byte) }}
+
+func getBuffer() *[]byte {
+ p := bufferPool.Get().(*[]byte)
+ *p = (*p)[:0]
+ return p
+}
+
+func putBuffer(p *[]byte) {
+ // Proper usage of a sync.Pool requires each entry to have approximately
+ // the same memory cost. To obtain this property when the stored type
+ // contains a variably-sized buffer, we add a hard limit on the maximum buffer
+ // to place back in the pool.
+ //
+ // See https://go.dev/issue/23199
+ if cap(*p) > 64<<10 {
+ *p = nil
+ }
+ bufferPool.Put(p)
+}
+
+// Output writes the output for a logging event. The string s contains
+// the text to print after the prefix specified by the flags of the
+// Logger. A newline is appended if the last character of s is not
+// already a newline. Calldepth is used to recover the PC and is
+// provided for generality, although at the moment on all pre-defined
+// paths it will be 2.
+func (l *Logger) Output(calldepth int, s string) error {
+ return l.output(0, calldepth+1, func(b []byte) []byte { // +1 for this frame.
+ return append(b, s...)
+ })
+}
+
+// output can take either a calldepth or a pc to get source line information.
+// It uses the pc if it is non-zero.
+func (l *Logger) output(pc uintptr, calldepth int, appendOutput func([]byte) []byte) error {
+ if l.isDiscard.Load() {
+ return nil
+ }
+
+ now := time.Now() // get this early.
+
+ // Load prefix and flag once so that their value is consistent within
+ // this call regardless of any concurrent changes to their value.
+ prefix := l.Prefix()
+ flag := l.Flags()
+
+ var file string
+ var line int
+ if flag&(Lshortfile|Llongfile) != 0 {
+ if pc == 0 {
+ var ok bool
+ _, file, line, ok = runtime.Caller(calldepth)
+ if !ok {
+ file = "???"
+ line = 0
+ }
+ } else {
+ fs := runtime.CallersFrames([]uintptr{pc})
+ f, _ := fs.Next()
+ file = f.File
+ if file == "" {
+ file = "???"
+ }
+ line = f.Line
+ }
+ }
+
+ buf := getBuffer()
+ defer putBuffer(buf)
+ formatHeader(buf, now, prefix, flag, file, line)
+ *buf = appendOutput(*buf)
+ if len(*buf) == 0 || (*buf)[len(*buf)-1] != '\n' {
+ *buf = append(*buf, '\n')
+ }
+
+ l.outMu.Lock()
+ defer l.outMu.Unlock()
+ _, err := l.out.Write(*buf)
+ return err
+}
+
+func init() {
+ internal.DefaultOutput = func(pc uintptr, data []byte) error {
+ return std.output(pc, 0, func(buf []byte) []byte {
+ return append(buf, data...)
+ })
+ }
+}
+
+// Print calls l.Output to print to the logger.
+// Arguments are handled in the manner of [fmt.Print].
+func (l *Logger) Print(v ...any) {
+ l.output(0, 2, func(b []byte) []byte {
+ return fmt.Append(b, v...)
+ })
+}
+
+// Printf calls l.Output to print to the logger.
+// Arguments are handled in the manner of [fmt.Printf].
+func (l *Logger) Printf(format string, v ...any) {
+ l.output(0, 2, func(b []byte) []byte {
+ return fmt.Appendf(b, format, v...)
+ })
+}
+
+// Println calls l.Output to print to the logger.
+// Arguments are handled in the manner of [fmt.Println].
+func (l *Logger) Println(v ...any) {
+ l.output(0, 2, func(b []byte) []byte {
+ return fmt.Appendln(b, v...)
+ })
+}
+
+// Fatal is equivalent to l.Print() followed by a call to [os.Exit](1).
+func (l *Logger) Fatal(v ...any) {
+ l.output(0, 2, func(b []byte) []byte {
+ return fmt.Append(b, v...)
+ })
+ os.Exit(1)
+}
+
+// Fatalf is equivalent to l.Printf() followed by a call to [os.Exit](1).
+func (l *Logger) Fatalf(format string, v ...any) {
+ l.output(0, 2, func(b []byte) []byte {
+ return fmt.Appendf(b, format, v...)
+ })
+ os.Exit(1)
+}
+
+// Fatalln is equivalent to l.Println() followed by a call to [os.Exit](1).
+func (l *Logger) Fatalln(v ...any) {
+ l.output(0, 2, func(b []byte) []byte {
+ return fmt.Appendln(b, v...)
+ })
+ os.Exit(1)
+}
+
+// Panic is equivalent to l.Print() followed by a call to panic().
+func (l *Logger) Panic(v ...any) {
+ s := fmt.Sprint(v...)
+ l.output(0, 2, func(b []byte) []byte {
+ return append(b, s...)
+ })
+ panic(s)
+}
+
+// Panicf is equivalent to l.Printf() followed by a call to panic().
+func (l *Logger) Panicf(format string, v ...any) {
+ s := fmt.Sprintf(format, v...)
+ l.output(0, 2, func(b []byte) []byte {
+ return append(b, s...)
+ })
+ panic(s)
+}
+
+// Panicln is equivalent to l.Println() followed by a call to panic().
+func (l *Logger) Panicln(v ...any) {
+ s := fmt.Sprintln(v...)
+ l.output(0, 2, func(b []byte) []byte {
+ return append(b, s...)
+ })
+ panic(s)
+}
+
+// Flags returns the output flags for the logger.
+// The flag bits are [Ldate], [Ltime], and so on.
+func (l *Logger) Flags() int {
+ return int(l.flag.Load())
+}
+
+// SetFlags sets the output flags for the logger.
+// The flag bits are [Ldate], [Ltime], and so on.
+func (l *Logger) SetFlags(flag int) {
+ l.flag.Store(int32(flag))
+}
+
+// Prefix returns the output prefix for the logger.
+func (l *Logger) Prefix() string {
+ if p := l.prefix.Load(); p != nil {
+ return *p
+ }
+ return ""
+}
+
+// SetPrefix sets the output prefix for the logger.
+func (l *Logger) SetPrefix(prefix string) {
+ l.prefix.Store(&prefix)
+}
+
+// Writer returns the output destination for the logger.
+func (l *Logger) Writer() io.Writer {
+ l.outMu.Lock()
+ defer l.outMu.Unlock()
+ return l.out
+}
+
+// SetOutput sets the output destination for the standard logger.
+func SetOutput(w io.Writer) {
+ std.SetOutput(w)
+}
+
+// Flags returns the output flags for the standard logger.
+// The flag bits are [Ldate], [Ltime], and so on.
+func Flags() int {
+ return std.Flags()
+}
+
+// SetFlags sets the output flags for the standard logger.
+// The flag bits are [Ldate], [Ltime], and so on.
+func SetFlags(flag int) {
+ std.SetFlags(flag)
+}
+
+// Prefix returns the output prefix for the standard logger.
+func Prefix() string {
+ return std.Prefix()
+}
+
+// SetPrefix sets the output prefix for the standard logger.
+func SetPrefix(prefix string) {
+ std.SetPrefix(prefix)
+}
+
+// Writer returns the output destination for the standard logger.
+func Writer() io.Writer {
+ return std.Writer()
+}
+
+// These functions write to the standard logger.
+
+// Print calls Output to print to the standard logger.
+// Arguments are handled in the manner of [fmt.Print].
+func Print(v ...any) {
+ std.output(0, 2, func(b []byte) []byte {
+ return fmt.Append(b, v...)
+ })
+}
+
+// Printf calls Output to print to the standard logger.
+// Arguments are handled in the manner of [fmt.Printf].
+func Printf(format string, v ...any) {
+ std.output(0, 2, func(b []byte) []byte {
+ return fmt.Appendf(b, format, v...)
+ })
+}
+
+// Println calls Output to print to the standard logger.
+// Arguments are handled in the manner of [fmt.Println].
+func Println(v ...any) {
+ std.output(0, 2, func(b []byte) []byte {
+ return fmt.Appendln(b, v...)
+ })
+}
+
+// Fatal is equivalent to [Print] followed by a call to [os.Exit](1).
+func Fatal(v ...any) {
+ std.output(0, 2, func(b []byte) []byte {
+ return fmt.Append(b, v...)
+ })
+ os.Exit(1)
+}
+
+// Fatalf is equivalent to [Printf] followed by a call to [os.Exit](1).
+func Fatalf(format string, v ...any) {
+ std.output(0, 2, func(b []byte) []byte {
+ return fmt.Appendf(b, format, v...)
+ })
+ os.Exit(1)
+}
+
+// Fatalln is equivalent to [Println] followed by a call to [os.Exit](1).
+func Fatalln(v ...any) {
+ std.output(0, 2, func(b []byte) []byte {
+ return fmt.Appendln(b, v...)
+ })
+ os.Exit(1)
+}
+
+// Panic is equivalent to [Print] followed by a call to panic().
+func Panic(v ...any) {
+ s := fmt.Sprint(v...)
+ std.output(0, 2, func(b []byte) []byte {
+ return append(b, s...)
+ })
+ panic(s)
+}
+
+// Panicf is equivalent to [Printf] followed by a call to panic().
+func Panicf(format string, v ...any) {
+ s := fmt.Sprintf(format, v...)
+ std.output(0, 2, func(b []byte) []byte {
+ return append(b, s...)
+ })
+ panic(s)
+}
+
+// Panicln is equivalent to [Println] followed by a call to panic().
+func Panicln(v ...any) {
+ s := fmt.Sprintln(v...)
+ std.output(0, 2, func(b []byte) []byte {
+ return append(b, s...)
+ })
+ panic(s)
+}
+
+// Output writes the output for a logging event. The string s contains
+// the text to print after the prefix specified by the flags of the
+// Logger. A newline is appended if the last character of s is not
+// already a newline. Calldepth is the count of the number of
+// frames to skip when computing the file name and line number
+// if [Llongfile] or [Lshortfile] is set; a value of 1 will print the details
+// for the caller of Output.
+func Output(calldepth int, s string) error {
+ return std.output(0, calldepth+1, func(b []byte) []byte { // +1 for this frame.
+ return append(b, s...)
+ })
+}
diff --git a/go/src/log/log_test.go b/go/src/log/log_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..5d5d38cc10dbaea262ed15e0dd42fe2787a512f7
--- /dev/null
+++ b/go/src/log/log_test.go
@@ -0,0 +1,364 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package log
+
+// These tests are too simple.
+
+import (
+ "bufio"
+ "bytes"
+ "errors"
+ "fmt"
+ "internal/testenv"
+ "io"
+ "os"
+ "os/exec"
+ "regexp"
+ "runtime"
+ "strings"
+ "sync"
+ "testing"
+ "time"
+)
+
+const (
+ Rdate = `[0-9][0-9][0-9][0-9]/[0-9][0-9]/[0-9][0-9]`
+ Rtime = `[0-9][0-9]:[0-9][0-9]:[0-9][0-9]`
+ Rmicroseconds = `\.[0-9][0-9][0-9][0-9][0-9][0-9]`
+ Rline = `(67|69):` // must update if the calls to l.Printf / l.Print below move
+ Rlongfile = `.*/[A-Za-z0-9_\-]+\.go:` + Rline
+ Rshortfile = `[A-Za-z0-9_\-]+\.go:` + Rline
+)
+
+type tester struct {
+ flag int
+ prefix string
+ pattern string // regexp that log output must match; we add ^ and expected_text$ always
+}
+
+var tests = []tester{
+ // individual pieces:
+ {0, "", ""},
+ {0, "XXX", "XXX"},
+ {Ldate, "", Rdate + " "},
+ {Ltime, "", Rtime + " "},
+ {Ltime | Lmsgprefix, "XXX", Rtime + " XXX"},
+ {Ltime | Lmicroseconds, "", Rtime + Rmicroseconds + " "},
+ {Lmicroseconds, "", Rtime + Rmicroseconds + " "}, // microsec implies time
+ {Llongfile, "", Rlongfile + " "},
+ {Lshortfile, "", Rshortfile + " "},
+ {Llongfile | Lshortfile, "", Rshortfile + " "}, // shortfile overrides longfile
+ // everything at once:
+ {Ldate | Ltime | Lmicroseconds | Llongfile, "XXX", "XXX" + Rdate + " " + Rtime + Rmicroseconds + " " + Rlongfile + " "},
+ {Ldate | Ltime | Lmicroseconds | Lshortfile, "XXX", "XXX" + Rdate + " " + Rtime + Rmicroseconds + " " + Rshortfile + " "},
+ {Ldate | Ltime | Lmicroseconds | Llongfile | Lmsgprefix, "XXX", Rdate + " " + Rtime + Rmicroseconds + " " + Rlongfile + " XXX"},
+ {Ldate | Ltime | Lmicroseconds | Lshortfile | Lmsgprefix, "XXX", Rdate + " " + Rtime + Rmicroseconds + " " + Rshortfile + " XXX"},
+}
+
+// Test using Println("hello", 23, "world") or using Printf("hello %d world", 23)
+func testPrint(t *testing.T, flag int, prefix string, pattern string, useFormat bool) {
+ buf := new(strings.Builder)
+ SetOutput(buf)
+ SetFlags(flag)
+ SetPrefix(prefix)
+ if useFormat {
+ Printf("hello %d world", 23)
+ } else {
+ Println("hello", 23, "world")
+ }
+ line := buf.String()
+ line = line[0 : len(line)-1]
+ pattern = "^" + pattern + "hello 23 world$"
+ matched, err := regexp.MatchString(pattern, line)
+ if err != nil {
+ t.Fatal("pattern did not compile:", err)
+ }
+ if !matched {
+ t.Errorf("log output should match %q is %q", pattern, line)
+ }
+ SetOutput(os.Stderr)
+}
+
+func TestDefault(t *testing.T) {
+ if got := Default(); got != std {
+ t.Errorf("Default [%p] should be std [%p]", got, std)
+ }
+}
+
+func TestAll(t *testing.T) {
+ for _, testcase := range tests {
+ testPrint(t, testcase.flag, testcase.prefix, testcase.pattern, false)
+ testPrint(t, testcase.flag, testcase.prefix, testcase.pattern, true)
+ }
+}
+
+func TestOutput(t *testing.T) {
+ const testString = "test"
+ var b strings.Builder
+ l := New(&b, "", 0)
+ l.Println(testString)
+ if expect := testString + "\n"; b.String() != expect {
+ t.Errorf("log output should match %q is %q", expect, b.String())
+ }
+}
+
+func TestNonNewLogger(t *testing.T) {
+ var l Logger
+ l.SetOutput(new(bytes.Buffer)) // minimal work to initialize a Logger
+ l.Print("hello")
+}
+
+func TestOutputRace(t *testing.T) {
+ var b bytes.Buffer
+ l := New(&b, "", 0)
+ var wg sync.WaitGroup
+ wg.Add(100)
+ for i := 0; i < 100; i++ {
+ go func() {
+ defer wg.Done()
+ l.SetFlags(0)
+ l.Output(0, "")
+ }()
+ }
+ wg.Wait()
+}
+
+func TestFlagAndPrefixSetting(t *testing.T) {
+ var b bytes.Buffer
+ l := New(&b, "Test:", LstdFlags)
+ f := l.Flags()
+ if f != LstdFlags {
+ t.Errorf("Flags 1: expected %x got %x", LstdFlags, f)
+ }
+ l.SetFlags(f | Lmicroseconds)
+ f = l.Flags()
+ if f != LstdFlags|Lmicroseconds {
+ t.Errorf("Flags 2: expected %x got %x", LstdFlags|Lmicroseconds, f)
+ }
+ p := l.Prefix()
+ if p != "Test:" {
+ t.Errorf(`Prefix: expected "Test:" got %q`, p)
+ }
+ l.SetPrefix("Reality:")
+ p = l.Prefix()
+ if p != "Reality:" {
+ t.Errorf(`Prefix: expected "Reality:" got %q`, p)
+ }
+ // Verify a log message looks right, with our prefix and microseconds present.
+ l.Print("hello")
+ pattern := "^Reality:" + Rdate + " " + Rtime + Rmicroseconds + " hello\n"
+ matched, err := regexp.Match(pattern, b.Bytes())
+ if err != nil {
+ t.Fatalf("pattern %q did not compile: %s", pattern, err)
+ }
+ if !matched {
+ t.Error("message did not match pattern")
+ }
+
+ // Ensure that a newline is added only if the buffer lacks a newline suffix.
+ b.Reset()
+ l.SetFlags(0)
+ l.SetPrefix("\n")
+ l.Output(0, "")
+ if got := b.String(); got != "\n" {
+ t.Errorf("message mismatch:\ngot %q\nwant %q", got, "\n")
+ }
+}
+
+func TestUTCFlag(t *testing.T) {
+ var b strings.Builder
+ l := New(&b, "Test:", LstdFlags)
+ l.SetFlags(Ldate | Ltime | LUTC)
+ // Verify a log message looks right in the right time zone. Quantize to the second only.
+ now := time.Now().UTC()
+ l.Print("hello")
+ want := fmt.Sprintf("Test:%d/%.2d/%.2d %.2d:%.2d:%.2d hello\n",
+ now.Year(), now.Month(), now.Day(), now.Hour(), now.Minute(), now.Second())
+ got := b.String()
+ if got == want {
+ return
+ }
+ // It's possible we crossed a second boundary between getting now and logging,
+ // so add a second and try again. This should very nearly always work.
+ now = now.Add(time.Second)
+ want = fmt.Sprintf("Test:%d/%.2d/%.2d %.2d:%.2d:%.2d hello\n",
+ now.Year(), now.Month(), now.Day(), now.Hour(), now.Minute(), now.Second())
+ if got == want {
+ return
+ }
+ t.Errorf("got %q; want %q", got, want)
+}
+
+func TestEmptyPrintCreatesLine(t *testing.T) {
+ var b strings.Builder
+ l := New(&b, "Header:", LstdFlags)
+ l.Print()
+ l.Println("non-empty")
+ output := b.String()
+ if n := strings.Count(output, "Header"); n != 2 {
+ t.Errorf("expected 2 headers, got %d", n)
+ }
+ if n := strings.Count(output, "\n"); n != 2 {
+ t.Errorf("expected 2 lines, got %d", n)
+ }
+}
+
+func TestDiscard(t *testing.T) {
+ l := New(io.Discard, "", 0)
+ s := strings.Repeat("a", 102400)
+ c := testing.AllocsPerRun(100, func() { l.Printf("%s", s) })
+ // One allocation for slice passed to Printf,
+ // but none for formatting of long string.
+ if c > 1 {
+ t.Errorf("got %v allocs, want at most 1", c)
+ }
+}
+
+func TestCallDepth(t *testing.T) {
+ if testing.Short() {
+ t.Skip("skipping test in short mode")
+ }
+
+ testenv.MustHaveExec(t)
+ ep, err := os.Executable()
+ if err != nil {
+ t.Fatalf("Executable failed: %v", err)
+ }
+
+ tests := []struct {
+ name string
+ log func()
+ }{
+ {"Fatal", func() { Fatal("Fatal") }},
+ {"Fatalf", func() { Fatalf("Fatalf") }},
+ {"Fatalln", func() { Fatalln("Fatalln") }},
+ {"Output", func() { Output(1, "Output") }},
+ {"Panic", func() { Panic("Panic") }},
+ {"Panicf", func() { Panicf("Panicf") }},
+ {"Panicln", func() { Panicf("Panicln") }},
+ {"Default.Fatal", func() { Default().Fatal("Default.Fatal") }},
+ {"Default.Fatalf", func() { Default().Fatalf("Default.Fatalf") }},
+ {"Default.Fatalln", func() { Default().Fatalln("Default.Fatalln") }},
+ {"Default.Output", func() { Default().Output(1, "Default.Output") }},
+ {"Default.Panic", func() { Default().Panic("Default.Panic") }},
+ {"Default.Panicf", func() { Default().Panicf("Default.Panicf") }},
+ {"Default.Panicln", func() { Default().Panicf("Default.Panicln") }},
+ }
+
+ // calculate the line offset until the first test case
+ _, _, line, ok := runtime.Caller(0)
+ if !ok {
+ t.Fatalf("runtime.Caller failed")
+ }
+ line -= len(tests) + 3
+
+ for i, tt := range tests {
+ t.Run(tt.name, func(t *testing.T) {
+ // some of these calls uses os.Exit() to spawn a command and capture output
+ const envVar = "LOGTEST_CALL_DEPTH"
+ if os.Getenv(envVar) == "1" {
+ SetFlags(Lshortfile)
+ tt.log()
+ os.Exit(1)
+ }
+
+ // spawn test executable
+ cmd := testenv.Command(t, ep,
+ "-test.run=^"+regexp.QuoteMeta(t.Name())+"$",
+ "-test.count=1",
+ )
+ cmd.Env = append(cmd.Environ(), envVar+"=1")
+
+ out, err := cmd.CombinedOutput()
+ if _, ok := errors.AsType[*exec.ExitError](err); !ok {
+ t.Fatalf("expected exec.ExitError: %v", err)
+ }
+
+ _, firstLine, err := bufio.ScanLines(out, true)
+ if err != nil {
+ t.Fatalf("failed to split line: %v", err)
+ }
+ got := string(firstLine)
+
+ want := fmt.Sprintf(
+ "log_test.go:%d: %s",
+ line+i, tt.name,
+ )
+ if got != want {
+ t.Errorf(
+ "output from %s() mismatch:\n\t got: %s\n\twant: %s",
+ tt.name, got, want,
+ )
+ }
+ })
+ }
+}
+
+func BenchmarkItoa(b *testing.B) {
+ dst := make([]byte, 0, 64)
+ for i := 0; i < b.N; i++ {
+ dst = dst[0:0]
+ itoa(&dst, 2015, 4) // year
+ itoa(&dst, 1, 2) // month
+ itoa(&dst, 30, 2) // day
+ itoa(&dst, 12, 2) // hour
+ itoa(&dst, 56, 2) // minute
+ itoa(&dst, 0, 2) // second
+ itoa(&dst, 987654, 6) // microsecond
+ }
+}
+
+func BenchmarkPrintln(b *testing.B) {
+ const testString = "test"
+ var buf bytes.Buffer
+ l := New(&buf, "", LstdFlags)
+ b.ReportAllocs()
+ for i := 0; i < b.N; i++ {
+ buf.Reset()
+ l.Println(testString)
+ }
+}
+
+func BenchmarkPrintlnNoFlags(b *testing.B) {
+ const testString = "test"
+ var buf bytes.Buffer
+ l := New(&buf, "", 0)
+ b.ReportAllocs()
+ for i := 0; i < b.N; i++ {
+ buf.Reset()
+ l.Println(testString)
+ }
+}
+
+// discard is identical to io.Discard,
+// but copied here to avoid the io.Discard optimization in Logger.
+type discard struct{}
+
+func (discard) Write(p []byte) (int, error) {
+ return len(p), nil
+}
+
+func BenchmarkConcurrent(b *testing.B) {
+ l := New(discard{}, "prefix: ", Ldate|Ltime|Lmicroseconds|Llongfile|Lmsgprefix)
+ var group sync.WaitGroup
+ for i := runtime.NumCPU(); i > 0; i-- {
+ group.Add(1)
+ go func() {
+ for i := 0; i < b.N; i++ {
+ l.Output(0, "hello, world!")
+ }
+ defer group.Done()
+ }()
+ }
+ group.Wait()
+}
+
+func BenchmarkDiscard(b *testing.B) {
+ l := New(io.Discard, "", LstdFlags|Lshortfile)
+ b.ReportAllocs()
+ for i := 0; i < b.N; i++ {
+ l.Printf("processing %d objects from bucket %q", 1234, "fizzbuzz")
+ }
+}
diff --git a/go/src/maps/example_test.go b/go/src/maps/example_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..b4ccff6d45c2b57e158b538b87bb4c95fe352404
--- /dev/null
+++ b/go/src/maps/example_test.go
@@ -0,0 +1,193 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package maps_test
+
+import (
+ "fmt"
+ "maps"
+ "slices"
+ "strings"
+)
+
+func ExampleClone() {
+ m1 := map[string]int{
+ "key": 1,
+ }
+ m2 := maps.Clone(m1)
+ m2["key"] = 100
+ fmt.Println(m1["key"])
+ fmt.Println(m2["key"])
+
+ m3 := map[string][]int{
+ "key": {1, 2, 3},
+ }
+ m4 := maps.Clone(m3)
+ fmt.Println(m4["key"][0])
+ m4["key"][0] = 100
+ fmt.Println(m3["key"][0])
+ fmt.Println(m4["key"][0])
+
+ // Output:
+ // 1
+ // 100
+ // 1
+ // 100
+ // 100
+}
+
+func ExampleCopy() {
+ m1 := map[string]int{
+ "one": 1,
+ "two": 2,
+ }
+ m2 := map[string]int{
+ "one": 10,
+ }
+
+ maps.Copy(m2, m1)
+ fmt.Println("m2 is:", m2)
+
+ m2["one"] = 100
+ fmt.Println("m1 is:", m1)
+ fmt.Println("m2 is:", m2)
+
+ m3 := map[string][]int{
+ "one": {1, 2, 3},
+ "two": {4, 5, 6},
+ }
+ m4 := map[string][]int{
+ "one": {7, 8, 9},
+ }
+
+ maps.Copy(m4, m3)
+ fmt.Println("m4 is:", m4)
+
+ m4["one"][0] = 100
+ fmt.Println("m3 is:", m3)
+ fmt.Println("m4 is:", m4)
+
+ // Output:
+ // m2 is: map[one:1 two:2]
+ // m1 is: map[one:1 two:2]
+ // m2 is: map[one:100 two:2]
+ // m4 is: map[one:[1 2 3] two:[4 5 6]]
+ // m3 is: map[one:[100 2 3] two:[4 5 6]]
+ // m4 is: map[one:[100 2 3] two:[4 5 6]]
+}
+
+func ExampleDeleteFunc() {
+ m := map[string]int{
+ "one": 1,
+ "two": 2,
+ "three": 3,
+ "four": 4,
+ }
+ maps.DeleteFunc(m, func(k string, v int) bool {
+ return v%2 != 0 // delete odd values
+ })
+ fmt.Println(m)
+ // Output:
+ // map[four:4 two:2]
+}
+
+func ExampleEqual() {
+ m1 := map[int]string{
+ 1: "one",
+ 10: "Ten",
+ 1000: "THOUSAND",
+ }
+ m2 := map[int]string{
+ 1: "one",
+ 10: "Ten",
+ 1000: "THOUSAND",
+ }
+ m3 := map[int]string{
+ 1: "one",
+ 10: "ten",
+ 1000: "thousand",
+ }
+
+ fmt.Println(maps.Equal(m1, m2))
+ fmt.Println(maps.Equal(m1, m3))
+ // Output:
+ // true
+ // false
+}
+
+func ExampleEqualFunc() {
+ m1 := map[int]string{
+ 1: "one",
+ 10: "Ten",
+ 1000: "THOUSAND",
+ }
+ m2 := map[int][]byte{
+ 1: []byte("One"),
+ 10: []byte("Ten"),
+ 1000: []byte("Thousand"),
+ }
+ eq := maps.EqualFunc(m1, m2, func(v1 string, v2 []byte) bool {
+ return strings.EqualFold(v1, string(v2))
+ })
+ fmt.Println(eq)
+ // Output:
+ // true
+}
+
+func ExampleAll() {
+ m1 := map[string]int{
+ "one": 1,
+ "two": 2,
+ }
+ m2 := map[string]int{
+ "one": 10,
+ }
+ maps.Insert(m2, maps.All(m1))
+ fmt.Println("m2 is:", m2)
+ // Output:
+ // m2 is: map[one:1 two:2]
+}
+
+func ExampleKeys() {
+ m1 := map[int]string{
+ 1: "one",
+ 10: "Ten",
+ 1000: "THOUSAND",
+ }
+ keys := slices.Sorted(maps.Keys(m1))
+ fmt.Println(keys)
+ // Output:
+ // [1 10 1000]
+}
+
+func ExampleValues() {
+ m1 := map[int]string{
+ 1: "one",
+ 10: "Ten",
+ 1000: "THOUSAND",
+ }
+ values := slices.Sorted(maps.Values(m1))
+ fmt.Println(values)
+ // Output:
+ // [THOUSAND Ten one]
+}
+
+func ExampleInsert() {
+ m1 := map[int]string{
+ 1000: "THOUSAND",
+ }
+ s1 := []string{"zero", "one", "two", "three"}
+ maps.Insert(m1, slices.All(s1))
+ fmt.Println("m1 is:", m1)
+ // Output:
+ // m1 is: map[0:zero 1:one 2:two 3:three 1000:THOUSAND]
+}
+
+func ExampleCollect() {
+ s1 := []string{"zero", "one", "two", "three"}
+ m1 := maps.Collect(slices.All(s1))
+ fmt.Println("m1 is:", m1)
+ // Output:
+ // m1 is: map[0:zero 1:one 2:two 3:three]
+}
diff --git a/go/src/maps/iter.go b/go/src/maps/iter.go
new file mode 100644
index 0000000000000000000000000000000000000000..32f2d514c150b98027d92b0a54a6c1b00fb0ef3d
--- /dev/null
+++ b/go/src/maps/iter.go
@@ -0,0 +1,62 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package maps
+
+import "iter"
+
+// All returns an iterator over key-value pairs from m.
+// The iteration order is not specified and is not guaranteed
+// to be the same from one call to the next.
+func All[Map ~map[K]V, K comparable, V any](m Map) iter.Seq2[K, V] {
+ return func(yield func(K, V) bool) {
+ for k, v := range m {
+ if !yield(k, v) {
+ return
+ }
+ }
+ }
+}
+
+// Keys returns an iterator over keys in m.
+// The iteration order is not specified and is not guaranteed
+// to be the same from one call to the next.
+func Keys[Map ~map[K]V, K comparable, V any](m Map) iter.Seq[K] {
+ return func(yield func(K) bool) {
+ for k := range m {
+ if !yield(k) {
+ return
+ }
+ }
+ }
+}
+
+// Values returns an iterator over values in m.
+// The iteration order is not specified and is not guaranteed
+// to be the same from one call to the next.
+func Values[Map ~map[K]V, K comparable, V any](m Map) iter.Seq[V] {
+ return func(yield func(V) bool) {
+ for _, v := range m {
+ if !yield(v) {
+ return
+ }
+ }
+ }
+}
+
+// Insert adds the key-value pairs from seq to m.
+// If a key in seq already exists in m, its value will be overwritten.
+func Insert[Map ~map[K]V, K comparable, V any](m Map, seq iter.Seq2[K, V]) {
+ for k, v := range seq {
+ m[k] = v
+ }
+}
+
+// Collect collects key-value pairs from seq into a new map
+// and returns it.
+func Collect[K comparable, V any](seq iter.Seq2[K, V]) map[K]V {
+ m := make(map[K]V)
+ Insert(m, seq)
+ return m
+}
diff --git a/go/src/maps/iter_test.go b/go/src/maps/iter_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..64ea42aeaf6b7b4ab48995ccdbfaeee57e9f86a9
--- /dev/null
+++ b/go/src/maps/iter_test.go
@@ -0,0 +1,116 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package maps
+
+import (
+ "slices"
+ "testing"
+)
+
+func TestAll(t *testing.T) {
+ for size := 0; size < 10; size++ {
+ m := make(map[int]int)
+ for i := range size {
+ m[i] = i
+ }
+ cnt := 0
+ for i, v := range All(m) {
+ v1, ok := m[i]
+ if !ok || v != v1 {
+ t.Errorf("at iteration %d got %d, %d want %d, %d", cnt, i, v, i, v1)
+ }
+ cnt++
+ }
+ if cnt != size {
+ t.Errorf("read %d values expected %d", cnt, size)
+ }
+ }
+}
+
+func TestKeys(t *testing.T) {
+ for size := 0; size < 10; size++ {
+ var want []int
+ m := make(map[int]int)
+ for i := range size {
+ m[i] = i
+ want = append(want, i)
+ }
+
+ var got []int
+ for k := range Keys(m) {
+ got = append(got, k)
+ }
+ slices.Sort(got)
+ if !slices.Equal(got, want) {
+ t.Errorf("Keys(%v) = %v, want %v", m, got, want)
+ }
+ }
+}
+
+func TestValues(t *testing.T) {
+ for size := 0; size < 10; size++ {
+ var want []int
+ m := make(map[int]int)
+ for i := range size {
+ m[i] = i
+ want = append(want, i)
+ }
+
+ var got []int
+ for v := range Values(m) {
+ got = append(got, v)
+ }
+ slices.Sort(got)
+ if !slices.Equal(got, want) {
+ t.Errorf("Values(%v) = %v, want %v", m, got, want)
+ }
+ }
+}
+
+func TestInsert(t *testing.T) {
+ got := map[int]int{
+ 1: 1,
+ 2: 1,
+ }
+ Insert(got, func(yield func(int, int) bool) {
+ for i := 0; i < 10; i += 2 {
+ if !yield(i, i+1) {
+ return
+ }
+ }
+ })
+
+ want := map[int]int{
+ 1: 1,
+ 2: 1,
+ }
+ for i, v := range map[int]int{
+ 0: 1,
+ 2: 3,
+ 4: 5,
+ 6: 7,
+ 8: 9,
+ } {
+ want[i] = v
+ }
+
+ if !Equal(got, want) {
+ t.Errorf("Insert got: %v, want: %v", got, want)
+ }
+}
+
+func TestCollect(t *testing.T) {
+ m := map[int]int{
+ 0: 1,
+ 2: 3,
+ 4: 5,
+ 6: 7,
+ 8: 9,
+ }
+ got := Collect(All(m))
+ if !Equal(got, m) {
+ t.Errorf("Collect got: %v, want: %v", got, m)
+ }
+}
diff --git a/go/src/maps/maps.go b/go/src/maps/maps.go
new file mode 100644
index 0000000000000000000000000000000000000000..b712dd3fe8ebaa26a4fac960cfa0eacd0adfa517
--- /dev/null
+++ b/go/src/maps/maps.go
@@ -0,0 +1,75 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package maps defines various functions useful with maps of any type.
+//
+// This package does not have any special handling for non-reflexive keys
+// (keys k where k != k), such as floating-point NaNs.
+package maps
+
+import (
+ _ "unsafe"
+)
+
+// Equal reports whether two maps contain the same key/value pairs.
+// Values are compared using ==.
+func Equal[M1, M2 ~map[K]V, K, V comparable](m1 M1, m2 M2) bool {
+ if len(m1) != len(m2) {
+ return false
+ }
+ for k, v1 := range m1 {
+ if v2, ok := m2[k]; !ok || v1 != v2 {
+ return false
+ }
+ }
+ return true
+}
+
+// EqualFunc is like Equal, but compares values using eq.
+// Keys are still compared with ==.
+func EqualFunc[M1 ~map[K]V1, M2 ~map[K]V2, K comparable, V1, V2 any](m1 M1, m2 M2, eq func(V1, V2) bool) bool {
+ if len(m1) != len(m2) {
+ return false
+ }
+ for k, v1 := range m1 {
+ if v2, ok := m2[k]; !ok || !eq(v1, v2) {
+ return false
+ }
+ }
+ return true
+}
+
+// clone is implemented in the runtime package.
+//
+//go:linkname clone maps.clone
+func clone(m any) any
+
+// Clone returns a copy of m. This is a shallow clone:
+// the new keys and values are set using ordinary assignment.
+func Clone[M ~map[K]V, K comparable, V any](m M) M {
+ // Preserve nil in case it matters.
+ if m == nil {
+ return nil
+ }
+ return clone(m).(M)
+}
+
+// Copy copies all key/value pairs in src adding them to dst.
+// When a key in src is already present in dst,
+// the value in dst will be overwritten by the value associated
+// with the key in src.
+func Copy[M1 ~map[K]V, M2 ~map[K]V, K comparable, V any](dst M1, src M2) {
+ for k, v := range src {
+ dst[k] = v
+ }
+}
+
+// DeleteFunc deletes any key/value pairs from m for which del returns true.
+func DeleteFunc[M ~map[K]V, K comparable, V any](m M, del func(K, V) bool) {
+ for k, v := range m {
+ if del(k, v) {
+ delete(m, k)
+ }
+ }
+}
diff --git a/go/src/maps/maps_test.go b/go/src/maps/maps_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..c8ee3cd0311f5ffe98a693ccb849ec50974eb77b
--- /dev/null
+++ b/go/src/maps/maps_test.go
@@ -0,0 +1,242 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package maps
+
+import (
+ "math"
+ "strconv"
+ "testing"
+)
+
+var m1 = map[int]int{1: 2, 2: 4, 4: 8, 8: 16}
+var m2 = map[int]string{1: "2", 2: "4", 4: "8", 8: "16"}
+
+func TestEqual(t *testing.T) {
+ if !Equal(m1, m1) {
+ t.Errorf("Equal(%v, %v) = false, want true", m1, m1)
+ }
+ if Equal(m1, (map[int]int)(nil)) {
+ t.Errorf("Equal(%v, nil) = true, want false", m1)
+ }
+ if Equal((map[int]int)(nil), m1) {
+ t.Errorf("Equal(nil, %v) = true, want false", m1)
+ }
+ if !Equal[map[int]int, map[int]int](nil, nil) {
+ t.Error("Equal(nil, nil) = false, want true")
+ }
+ if ms := map[int]int{1: 2}; Equal(m1, ms) {
+ t.Errorf("Equal(%v, %v) = true, want false", m1, ms)
+ }
+
+ // Comparing NaN for equality is expected to fail.
+ mf := map[int]float64{1: 0, 2: math.NaN()}
+ if Equal(mf, mf) {
+ t.Errorf("Equal(%v, %v) = true, want false", mf, mf)
+ }
+}
+
+// equal is simply ==.
+func equal[T comparable](v1, v2 T) bool {
+ return v1 == v2
+}
+
+// equalNaN is like == except that all NaNs are equal.
+func equalNaN[T comparable](v1, v2 T) bool {
+ isNaN := func(f T) bool { return f != f }
+ return v1 == v2 || (isNaN(v1) && isNaN(v2))
+}
+
+// equalIntStr compares ints and strings.
+func equalIntStr(v1 int, v2 string) bool {
+ return strconv.Itoa(v1) == v2
+}
+
+func TestEqualFunc(t *testing.T) {
+ if !EqualFunc(m1, m1, equal[int]) {
+ t.Errorf("EqualFunc(%v, %v, equal) = false, want true", m1, m1)
+ }
+ if EqualFunc(m1, (map[int]int)(nil), equal[int]) {
+ t.Errorf("EqualFunc(%v, nil, equal) = true, want false", m1)
+ }
+ if EqualFunc((map[int]int)(nil), m1, equal[int]) {
+ t.Errorf("EqualFunc(nil, %v, equal) = true, want false", m1)
+ }
+ if !EqualFunc[map[int]int, map[int]int](nil, nil, equal[int]) {
+ t.Error("EqualFunc(nil, nil, equal) = false, want true")
+ }
+ if ms := map[int]int{1: 2}; EqualFunc(m1, ms, equal[int]) {
+ t.Errorf("EqualFunc(%v, %v, equal) = true, want false", m1, ms)
+ }
+
+ // Comparing NaN for equality is expected to fail.
+ mf := map[int]float64{1: 0, 2: math.NaN()}
+ if EqualFunc(mf, mf, equal[float64]) {
+ t.Errorf("EqualFunc(%v, %v, equal) = true, want false", mf, mf)
+ }
+ // But it should succeed using equalNaN.
+ if !EqualFunc(mf, mf, equalNaN[float64]) {
+ t.Errorf("EqualFunc(%v, %v, equalNaN) = false, want true", mf, mf)
+ }
+
+ if !EqualFunc(m1, m2, equalIntStr) {
+ t.Errorf("EqualFunc(%v, %v, equalIntStr) = false, want true", m1, m2)
+ }
+}
+
+func TestClone(t *testing.T) {
+ mc := Clone(m1)
+ if !Equal(mc, m1) {
+ t.Errorf("Clone(%v) = %v, want %v", m1, mc, m1)
+ }
+ mc[16] = 32
+ if Equal(mc, m1) {
+ t.Errorf("Equal(%v, %v) = true, want false", mc, m1)
+ }
+}
+
+func TestCloneNil(t *testing.T) {
+ var m1 map[string]int
+ mc := Clone(m1)
+ if mc != nil {
+ t.Errorf("Clone(%v) = %v, want %v", m1, mc, m1)
+ }
+}
+
+func TestCopy(t *testing.T) {
+ mc := Clone(m1)
+ Copy(mc, mc)
+ if !Equal(mc, m1) {
+ t.Errorf("Copy(%v, %v) = %v, want %v", m1, m1, mc, m1)
+ }
+ Copy(mc, map[int]int{16: 32})
+ want := map[int]int{1: 2, 2: 4, 4: 8, 8: 16, 16: 32}
+ if !Equal(mc, want) {
+ t.Errorf("Copy result = %v, want %v", mc, want)
+ }
+
+ type M1 map[int]bool
+ type M2 map[int]bool
+ Copy(make(M1), make(M2))
+}
+
+func TestDeleteFunc(t *testing.T) {
+ mc := Clone(m1)
+ DeleteFunc(mc, func(int, int) bool { return false })
+ if !Equal(mc, m1) {
+ t.Errorf("DeleteFunc(%v, true) = %v, want %v", m1, mc, m1)
+ }
+ DeleteFunc(mc, func(k, v int) bool { return k > 3 })
+ want := map[int]int{1: 2, 2: 4}
+ if !Equal(mc, want) {
+ t.Errorf("DeleteFunc result = %v, want %v", mc, want)
+ }
+}
+
+var n map[int]int
+
+func BenchmarkMapClone(b *testing.B) {
+ var m = make(map[int]int)
+ for i := 0; i < 1000000; i++ {
+ m[i] = i
+ }
+ b.ResetTimer()
+ for i := 0; i < b.N; i++ {
+ n = Clone(m)
+ }
+}
+
+func TestCloneWithDelete(t *testing.T) {
+ var m = make(map[int]int)
+ for i := 0; i < 32; i++ {
+ m[i] = i
+ }
+ for i := 8; i < 32; i++ {
+ delete(m, i)
+ }
+ m2 := Clone(m)
+ if len(m2) != 8 {
+ t.Errorf("len2(m2) = %d, want %d", len(m2), 8)
+ }
+ for i := 0; i < 8; i++ {
+ if m2[i] != m[i] {
+ t.Errorf("m2[%d] = %d, want %d", i, m2[i], m[i])
+ }
+ }
+}
+
+func TestCloneWithMapAssign(t *testing.T) {
+ var m = make(map[int]int)
+ const N = 25
+ for i := 0; i < N; i++ {
+ m[i] = i
+ }
+ m2 := Clone(m)
+ if len(m2) != N {
+ t.Errorf("len2(m2) = %d, want %d", len(m2), N)
+ }
+ for i := 0; i < N; i++ {
+ if m2[i] != m[i] {
+ t.Errorf("m2[%d] = %d, want %d", i, m2[i], m[i])
+ }
+ }
+}
+
+func TestCloneLarge(t *testing.T) {
+ // See issue 64474.
+ type K [17]float64 // > 128 bytes
+ type V [17]float64
+
+ var zero float64
+ negZero := -zero
+
+ for tst := 0; tst < 3; tst++ {
+ // Initialize m with a key and value.
+ m := map[K]V{}
+ var k1 K
+ var v1 V
+ m[k1] = v1
+
+ switch tst {
+ case 0: // nothing, just a 1-entry map
+ case 1:
+ // Add more entries to make it 2 buckets
+ // 1 entry already
+ // 7 more fill up 1 bucket
+ // 1 more to grow to 2 buckets
+ for i := 0; i < 7+1; i++ {
+ m[K{float64(i) + 1}] = V{}
+ }
+ case 2:
+ // Capture the map mid-grow
+ // 1 entry already
+ // 7 more fill up 1 bucket
+ // 5 more (13 total) fill up 2 buckets
+ // 13 more (26 total) fill up 4 buckets
+ // 1 more to start the 4->8 bucket grow
+ for i := 0; i < 7+5+13+1; i++ {
+ m[K{float64(i) + 1}] = V{}
+ }
+ }
+
+ // Clone m, which should freeze the map's contents.
+ c := Clone(m)
+
+ // Update m with new key and value.
+ k2, v2 := k1, v1
+ k2[0] = negZero
+ v2[0] = 1.0
+ m[k2] = v2
+
+ // Make sure c still has its old key and value.
+ for k, v := range c {
+ if math.Signbit(k[0]) {
+ t.Errorf("tst%d: sign bit of key changed; got %v want %v", tst, k, k1)
+ }
+ if v != v1 {
+ t.Errorf("tst%d: value changed; got %v want %v", tst, v, v1)
+ }
+ }
+ }
+}
diff --git a/go/src/math/abs.go b/go/src/math/abs.go
new file mode 100644
index 0000000000000000000000000000000000000000..08be14548dd778c37411864ad119e859e8855151
--- /dev/null
+++ b/go/src/math/abs.go
@@ -0,0 +1,15 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Abs returns the absolute value of x.
+//
+// Special cases are:
+//
+// Abs(±Inf) = +Inf
+// Abs(NaN) = NaN
+func Abs(x float64) float64 {
+ return Float64frombits(Float64bits(x) &^ (1 << 63))
+}
diff --git a/go/src/math/acos_s390x.s b/go/src/math/acos_s390x.s
new file mode 100644
index 0000000000000000000000000000000000000000..4431b99e1cbd7e2e41f21ee69e1ff3db712821d6
--- /dev/null
+++ b/go/src/math/acos_s390x.s
@@ -0,0 +1,144 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// Minimax polynomial coefficients and other constants
+DATA ·acosrodataL13<> + 0(SB)/8, $0.314159265358979323E+01 //pi
+DATA ·acosrodataL13<> + 8(SB)/8, $-0.0
+DATA ·acosrodataL13<> + 16(SB)/8, $0x7ff8000000000000 //Nan
+DATA ·acosrodataL13<> + 24(SB)/8, $-1.0
+DATA ·acosrodataL13<> + 32(SB)/8, $1.0
+DATA ·acosrodataL13<> + 40(SB)/8, $0.166666666666651626E+00
+DATA ·acosrodataL13<> + 48(SB)/8, $0.750000000042621169E-01
+DATA ·acosrodataL13<> + 56(SB)/8, $0.446428567178116477E-01
+DATA ·acosrodataL13<> + 64(SB)/8, $0.303819660378071894E-01
+DATA ·acosrodataL13<> + 72(SB)/8, $0.223715011892010405E-01
+DATA ·acosrodataL13<> + 80(SB)/8, $0.173659424522364952E-01
+DATA ·acosrodataL13<> + 88(SB)/8, $0.137810186504372266E-01
+DATA ·acosrodataL13<> + 96(SB)/8, $0.134066870961173521E-01
+DATA ·acosrodataL13<> + 104(SB)/8, $-.412335502831898721E-02
+DATA ·acosrodataL13<> + 112(SB)/8, $0.867383739532082719E-01
+DATA ·acosrodataL13<> + 120(SB)/8, $-.328765950607171649E+00
+DATA ·acosrodataL13<> + 128(SB)/8, $0.110401073869414626E+01
+DATA ·acosrodataL13<> + 136(SB)/8, $-.270694366992537307E+01
+DATA ·acosrodataL13<> + 144(SB)/8, $0.500196500770928669E+01
+DATA ·acosrodataL13<> + 152(SB)/8, $-.665866959108585165E+01
+DATA ·acosrodataL13<> + 160(SB)/8, $-.344895269334086578E+01
+DATA ·acosrodataL13<> + 168(SB)/8, $0.927437952918301659E+00
+DATA ·acosrodataL13<> + 176(SB)/8, $0.610487478874645653E+01
+DATA ·acosrodataL13<> + 184(SB)/8, $0.157079632679489656e+01
+DATA ·acosrodataL13<> + 192(SB)/8, $0.0
+GLOBL ·acosrodataL13<> + 0(SB), RODATA, $200
+
+// Acos returns the arccosine, in radians, of the argument.
+//
+// Special case is:
+// Acos(x) = NaN if x < -1 or x > 1
+// The algorithm used is minimax polynomial approximation
+// with coefficients determined with a Remez exchange algorithm.
+
+TEXT ·acosAsm(SB), NOSPLIT, $0-16
+ FMOVD x+0(FP), F0
+ MOVD $·acosrodataL13<>+0(SB), R9
+ LGDR F0, R12
+ FMOVD F0, F10
+ SRAD $32, R12
+ WORD $0xC0293FE6 //iilf %r2,1072079005
+ BYTE $0xA0
+ BYTE $0x9D
+ WORD $0xB917001C //llgtr %r1,%r12
+ CMPW R1,R2
+ BGT L2
+ FMOVD 192(R9), F8
+ FMADD F0, F0, F8
+ FMOVD 184(R9), F1
+L3:
+ WFMDB V8, V8, V2
+ FMOVD 176(R9), F6
+ FMOVD 168(R9), F0
+ FMOVD 160(R9), F4
+ WFMADB V2, V0, V6, V0
+ FMOVD 152(R9), F6
+ WFMADB V2, V4, V6, V4
+ FMOVD 144(R9), F6
+ WFMADB V2, V0, V6, V0
+ FMOVD 136(R9), F6
+ WFMADB V2, V4, V6, V4
+ FMOVD 128(R9), F6
+ WFMADB V2, V0, V6, V0
+ FMOVD 120(R9), F6
+ WFMADB V2, V4, V6, V4
+ FMOVD 112(R9), F6
+ WFMADB V2, V0, V6, V0
+ FMOVD 104(R9), F6
+ WFMADB V2, V4, V6, V4
+ FMOVD 96(R9), F6
+ WFMADB V2, V0, V6, V0
+ FMOVD 88(R9), F6
+ WFMADB V2, V4, V6, V4
+ FMOVD 80(R9), F6
+ WFMADB V2, V0, V6, V0
+ FMOVD 72(R9), F6
+ WFMADB V2, V4, V6, V4
+ FMOVD 64(R9), F6
+ WFMADB V2, V0, V6, V0
+ FMOVD 56(R9), F6
+ WFMADB V2, V4, V6, V4
+ FMOVD 48(R9), F6
+ WFMADB V2, V0, V6, V0
+ FMOVD 40(R9), F6
+ WFMADB V2, V4, V6, V2
+ FMOVD 192(R9), F4
+ WFMADB V8, V0, V2, V0
+ WFMADB V10, V8, V4, V8
+ FMADD F0, F8, F10
+ WFSDB V10, V1, V10
+L1:
+ FMOVD F10, ret+8(FP)
+ RET
+
+L2:
+ WORD $0xC0293FEF //iilf %r2,1072693247
+ BYTE $0xFF
+ BYTE $0xFF
+ CMPW R1, R2
+ BLE L12
+L4:
+ WORD $0xED009020 //cdb %f0,.L34-.L13(%r9)
+ BYTE $0x00
+ BYTE $0x19
+ BEQ L8
+ WORD $0xED009018 //cdb %f0,.L35-.L13(%r9)
+ BYTE $0x00
+ BYTE $0x19
+ BEQ L9
+ WFCEDBS V10, V10, V0
+ BVS L1
+ FMOVD 16(R9), F10
+ BR L1
+L12:
+ FMOVD 24(R9), F0
+ FMADD F10, F10, F0
+ LCDBR F0, F8
+ WORD $0xED009008 //cdb %f0,.L37-.L13(%r9)
+ BYTE $0x00
+ BYTE $0x19
+ FSQRT F8, F10
+L5:
+ MOVW R12, R4
+ CMPBLE R4, $0, L7
+ LCDBR F10, F10
+ FMOVD $0, F1
+ BR L3
+L9:
+ FMOVD 0(R9), F10
+ BR L1
+L8:
+ FMOVD $0, F0
+ FMOVD F0, ret+8(FP)
+ RET
+L7:
+ FMOVD 0(R9), F1
+ BR L3
diff --git a/go/src/math/acosh.go b/go/src/math/acosh.go
new file mode 100644
index 0000000000000000000000000000000000000000..a85d003d3eabe768995aaa7a6976b155dbfe6836
--- /dev/null
+++ b/go/src/math/acosh.go
@@ -0,0 +1,65 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// The original C code, the long comment, and the constants
+// below are from FreeBSD's /usr/src/lib/msun/src/e_acosh.c
+// and came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+//
+// __ieee754_acosh(x)
+// Method :
+// Based on
+// acosh(x) = log [ x + sqrt(x*x-1) ]
+// we have
+// acosh(x) := log(x)+ln2, if x is large; else
+// acosh(x) := log(2x-1/(sqrt(x*x-1)+x)) if x>2; else
+// acosh(x) := log1p(t+sqrt(2.0*t+t*t)); where t=x-1.
+//
+// Special cases:
+// acosh(x) is NaN with signal if x<1.
+// acosh(NaN) is NaN without signal.
+//
+
+// Acosh returns the inverse hyperbolic cosine of x.
+//
+// Special cases are:
+//
+// Acosh(+Inf) = +Inf
+// Acosh(x) = NaN if x < 1
+// Acosh(NaN) = NaN
+func Acosh(x float64) float64 {
+ if haveArchAcosh {
+ return archAcosh(x)
+ }
+ return acosh(x)
+}
+
+func acosh(x float64) float64 {
+ const Large = 1 << 28 // 2**28
+ // first case is special case
+ switch {
+ case x < 1 || IsNaN(x):
+ return NaN()
+ case x == 1:
+ return 0
+ case x >= Large:
+ return Log(x) + Ln2 // x > 2**28
+ case x > 2:
+ return Log(2*x - 1/(x+Sqrt(x*x-1))) // 2**28 > x > 2
+ }
+ t := x - 1
+ return Log1p(t + Sqrt(2*t+t*t)) // 2 >= x > 1
+}
diff --git a/go/src/math/acosh_s390x.s b/go/src/math/acosh_s390x.s
new file mode 100644
index 0000000000000000000000000000000000000000..9294c48e6b92b3e8669d076ad4881bc7fa98aa82
--- /dev/null
+++ b/go/src/math/acosh_s390x.s
@@ -0,0 +1,158 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// Minimax polynomial coefficients and other constants
+DATA ·acoshrodataL11<> + 0(SB)/8, $-1.0
+DATA ·acoshrodataL11<> + 8(SB)/8, $.41375273347623353626
+DATA ·acoshrodataL11<> + 16(SB)/8, $.51487302528619766235E+04
+DATA ·acoshrodataL11<> + 24(SB)/8, $-1.67526912689208984375
+DATA ·acoshrodataL11<> + 32(SB)/8, $0.181818181818181826E+00
+DATA ·acoshrodataL11<> + 40(SB)/8, $-.165289256198351540E-01
+DATA ·acoshrodataL11<> + 48(SB)/8, $0.200350613573012186E-02
+DATA ·acoshrodataL11<> + 56(SB)/8, $-.273205381970859341E-03
+DATA ·acoshrodataL11<> + 64(SB)/8, $0.397389654305194527E-04
+DATA ·acoshrodataL11<> + 72(SB)/8, $0.938370938292558173E-06
+DATA ·acoshrodataL11<> + 80(SB)/8, $-.602107458843052029E-05
+DATA ·acoshrodataL11<> + 88(SB)/8, $0.212881813645679599E-07
+DATA ·acoshrodataL11<> + 96(SB)/8, $-.148682720127920854E-06
+DATA ·acoshrodataL11<> + 104(SB)/8, $-5.5
+DATA ·acoshrodataL11<> + 112(SB)/8, $0x7ff8000000000000 //Nan
+GLOBL ·acoshrodataL11<> + 0(SB), RODATA, $120
+
+// Table of log correction terms
+DATA ·acoshtab2068<> + 0(SB)/8, $0.585235384085551248E-01
+DATA ·acoshtab2068<> + 8(SB)/8, $0.412206153771168640E-01
+DATA ·acoshtab2068<> + 16(SB)/8, $0.273839003221648339E-01
+DATA ·acoshtab2068<> + 24(SB)/8, $0.166383778368856480E-01
+DATA ·acoshtab2068<> + 32(SB)/8, $0.866678223433169637E-02
+DATA ·acoshtab2068<> + 40(SB)/8, $0.319831684989627514E-02
+DATA ·acoshtab2068<> + 48(SB)/8, $0.0
+DATA ·acoshtab2068<> + 56(SB)/8, $-.113006378583725549E-02
+DATA ·acoshtab2068<> + 64(SB)/8, $-.367979419636602491E-03
+DATA ·acoshtab2068<> + 72(SB)/8, $0.213172484510484979E-02
+DATA ·acoshtab2068<> + 80(SB)/8, $0.623271047682013536E-02
+DATA ·acoshtab2068<> + 88(SB)/8, $0.118140812789696885E-01
+DATA ·acoshtab2068<> + 96(SB)/8, $0.187681358930914206E-01
+DATA ·acoshtab2068<> + 104(SB)/8, $0.269985148668178992E-01
+DATA ·acoshtab2068<> + 112(SB)/8, $0.364186619761331328E-01
+DATA ·acoshtab2068<> + 120(SB)/8, $0.469505379381388441E-01
+GLOBL ·acoshtab2068<> + 0(SB), RODATA, $128
+
+// Acosh returns the inverse hyperbolic cosine of the argument.
+//
+// Special cases are:
+// Acosh(+Inf) = +Inf
+// Acosh(x) = NaN if x < 1
+// Acosh(NaN) = NaN
+// The algorithm used is minimax polynomial approximation
+// with coefficients determined with a Remez exchange algorithm.
+
+TEXT ·acoshAsm(SB), NOSPLIT, $0-16
+ FMOVD x+0(FP), F0
+ MOVD $·acoshrodataL11<>+0(SB), R9
+ LGDR F0, R1
+ WORD $0xC0295FEF //iilf %r2,1609564159
+ BYTE $0xFF
+ BYTE $0xFF
+ SRAD $32, R1
+ CMPW R1, R2
+ BGT L2
+ WORD $0xC0293FEF //iilf %r2,1072693247
+ BYTE $0xFF
+ BYTE $0xFF
+ CMPW R1, R2
+ BGT L10
+L3:
+ WFCEDBS V0, V0, V2
+ BVS L1
+ FMOVD 112(R9), F0
+L1:
+ FMOVD F0, ret+8(FP)
+ RET
+L2:
+ WORD $0xC0297FEF //iilf %r2,2146435071
+ BYTE $0xFF
+ BYTE $0xFF
+ MOVW R1, R6
+ MOVW R2, R7
+ CMPBGT R6, R7, L1
+ FMOVD F0, F8
+ FMOVD $0, F0
+ WFADB V0, V8, V0
+ WORD $0xC0398006 //iilf %r3,2147909631
+ BYTE $0x7F
+ BYTE $0xFF
+ LGDR F0, R5
+ SRAD $32, R5
+ MOVH $0x0, R1
+ SUBW R5, R3
+ FMOVD $0, F10
+ RISBGZ $32, $47, $0, R3, R4
+ RISBGZ $57, $60, $51, R3, R3
+ BYTE $0x18 //lr %r2,%r4
+ BYTE $0x24
+ RISBGN $0, $31, $32, R4, R1
+ SUBW $0x100000, R2
+ SRAW $8, R2, R2
+ ORW $0x45000000, R2
+L5:
+ LDGR R1, F0
+ FMOVD 104(R9), F2
+ FMADD F8, F0, F2
+ FMOVD 96(R9), F4
+ WFMADB V10, V0, V2, V0
+ FMOVD 88(R9), F6
+ FMOVD 80(R9), F2
+ WFMADB V0, V6, V4, V6
+ FMOVD 72(R9), F1
+ WFMDB V0, V0, V4
+ WFMADB V0, V1, V2, V1
+ FMOVD 64(R9), F2
+ WFMADB V6, V4, V1, V6
+ FMOVD 56(R9), F1
+ RISBGZ $57, $60, $0, R3, R3
+ WFMADB V0, V2, V1, V2
+ FMOVD 48(R9), F1
+ WFMADB V4, V6, V2, V6
+ FMOVD 40(R9), F2
+ WFMADB V0, V1, V2, V1
+ VLVGF $0, R2, V2
+ WFMADB V4, V6, V1, V4
+ LDEBR F2, F2
+ FMOVD 32(R9), F6
+ WFMADB V0, V4, V6, V4
+ FMOVD 24(R9), F1
+ FMOVD 16(R9), F6
+ MOVD $·acoshtab2068<>+0(SB), R1
+ WFMADB V2, V1, V6, V2
+ FMOVD 0(R3)(R1*1), F3
+ WFMADB V0, V4, V3, V0
+ FMOVD 8(R9), F4
+ FMADD F4, F2, F0
+ FMOVD F0, ret+8(FP)
+ RET
+L10:
+ FMOVD F0, F8
+ FMOVD 0(R9), F0
+ FMADD F8, F8, F0
+ LTDBR F0, F0
+ FSQRT F0, F10
+L4:
+ WFADB V10, V8, V0
+ WORD $0xC0398006 //iilf %r3,2147909631
+ BYTE $0x7F
+ BYTE $0xFF
+ LGDR F0, R5
+ SRAD $32, R5
+ MOVH $0x0, R1
+ SUBW R5, R3
+ SRAW $8, R3, R2
+ RISBGZ $32, $47, $0, R3, R4
+ ANDW $0xFFFFFF00, R2
+ RISBGZ $57, $60, $51, R3, R3
+ ORW $0x45000000, R2
+ RISBGN $0, $31, $32, R4, R1
+ BR L5
diff --git a/go/src/math/all_test.go b/go/src/math/all_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..4e5f4517629dd83565e18713c9d65bdca8597c04
--- /dev/null
+++ b/go/src/math/all_test.go
@@ -0,0 +1,3960 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math_test
+
+import (
+ "fmt"
+ . "math"
+ "testing"
+ "unsafe"
+)
+
+var vf = []float64{
+ 4.9790119248836735e+00,
+ 7.7388724745781045e+00,
+ -2.7688005719200159e-01,
+ -5.0106036182710749e+00,
+ 9.6362937071984173e+00,
+ 2.9263772392439646e+00,
+ 5.2290834314593066e+00,
+ 2.7279399104360102e+00,
+ 1.8253080916808550e+00,
+ -8.6859247685756013e+00,
+}
+
+// The expected results below were computed by the high precision calculators
+// at https://keisan.casio.com/. More exact input values (array vf[], above)
+// were obtained by printing them with "%.26f". The answers were calculated
+// to 26 digits (by using the "Digit number" drop-down control of each
+// calculator).
+var acos = []float64{
+ 1.0496193546107222142571536e+00,
+ 6.8584012813664425171660692e-01,
+ 1.5984878714577160325521819e+00,
+ 2.0956199361475859327461799e+00,
+ 2.7053008467824138592616927e-01,
+ 1.2738121680361776018155625e+00,
+ 1.0205369421140629186287407e+00,
+ 1.2945003481781246062157835e+00,
+ 1.3872364345374451433846657e+00,
+ 2.6231510803970463967294145e+00,
+}
+var acosh = []float64{
+ 2.4743347004159012494457618e+00,
+ 2.8576385344292769649802701e+00,
+ 7.2796961502981066190593175e-01,
+ 2.4796794418831451156471977e+00,
+ 3.0552020742306061857212962e+00,
+ 2.044238592688586588942468e+00,
+ 2.5158701513104513595766636e+00,
+ 1.99050839282411638174299e+00,
+ 1.6988625798424034227205445e+00,
+ 2.9611454842470387925531875e+00,
+}
+var asin = []float64{
+ 5.2117697218417440497416805e-01,
+ 8.8495619865825236751471477e-01,
+ -02.769154466281941332086016e-02,
+ -5.2482360935268931351485822e-01,
+ 1.3002662421166552333051524e+00,
+ 2.9698415875871901741575922e-01,
+ 5.5025938468083370060258102e-01,
+ 2.7629597861677201301553823e-01,
+ 1.83559892257451475846656e-01,
+ -1.0523547536021497774980928e+00,
+}
+var asinh = []float64{
+ 2.3083139124923523427628243e+00,
+ 2.743551594301593620039021e+00,
+ -2.7345908534880091229413487e-01,
+ -2.3145157644718338650499085e+00,
+ 2.9613652154015058521951083e+00,
+ 1.7949041616585821933067568e+00,
+ 2.3564032905983506405561554e+00,
+ 1.7287118790768438878045346e+00,
+ 1.3626658083714826013073193e+00,
+ -2.8581483626513914445234004e+00,
+}
+var atan = []float64{
+ 1.372590262129621651920085e+00,
+ 1.442290609645298083020664e+00,
+ -2.7011324359471758245192595e-01,
+ -1.3738077684543379452781531e+00,
+ 1.4673921193587666049154681e+00,
+ 1.2415173565870168649117764e+00,
+ 1.3818396865615168979966498e+00,
+ 1.2194305844639670701091426e+00,
+ 1.0696031952318783760193244e+00,
+ -1.4561721938838084990898679e+00,
+}
+var atanh = []float64{
+ 5.4651163712251938116878204e-01,
+ 1.0299474112843111224914709e+00,
+ -2.7695084420740135145234906e-02,
+ -5.5072096119207195480202529e-01,
+ 1.9943940993171843235906642e+00,
+ 3.01448604578089708203017e-01,
+ 5.8033427206942188834370595e-01,
+ 2.7987997499441511013958297e-01,
+ 1.8459947964298794318714228e-01,
+ -1.3273186910532645867272502e+00,
+}
+var atan2 = []float64{
+ 1.1088291730037004444527075e+00,
+ 9.1218183188715804018797795e-01,
+ 1.5984772603216203736068915e+00,
+ 2.0352918654092086637227327e+00,
+ 8.0391819139044720267356014e-01,
+ 1.2861075249894661588866752e+00,
+ 1.0889904479131695712182587e+00,
+ 1.3044821793397925293797357e+00,
+ 1.3902530903455392306872261e+00,
+ 2.2859857424479142655411058e+00,
+}
+var cbrt = []float64{
+ 1.7075799841925094446722675e+00,
+ 1.9779982212970353936691498e+00,
+ -6.5177429017779910853339447e-01,
+ -1.7111838886544019873338113e+00,
+ 2.1279920909827937423960472e+00,
+ 1.4303536770460741452312367e+00,
+ 1.7357021059106154902341052e+00,
+ 1.3972633462554328350552916e+00,
+ 1.2221149580905388454977636e+00,
+ -2.0556003730500069110343596e+00,
+}
+var ceil = []float64{
+ 5.0000000000000000e+00,
+ 8.0000000000000000e+00,
+ Copysign(0, -1),
+ -5.0000000000000000e+00,
+ 1.0000000000000000e+01,
+ 3.0000000000000000e+00,
+ 6.0000000000000000e+00,
+ 3.0000000000000000e+00,
+ 2.0000000000000000e+00,
+ -8.0000000000000000e+00,
+}
+var copysign = []float64{
+ -4.9790119248836735e+00,
+ -7.7388724745781045e+00,
+ -2.7688005719200159e-01,
+ -5.0106036182710749e+00,
+ -9.6362937071984173e+00,
+ -2.9263772392439646e+00,
+ -5.2290834314593066e+00,
+ -2.7279399104360102e+00,
+ -1.8253080916808550e+00,
+ -8.6859247685756013e+00,
+}
+var cos = []float64{
+ 2.634752140995199110787593e-01,
+ 1.148551260848219865642039e-01,
+ 9.6191297325640768154550453e-01,
+ 2.938141150061714816890637e-01,
+ -9.777138189897924126294461e-01,
+ -9.7693041344303219127199518e-01,
+ 4.940088096948647263961162e-01,
+ -9.1565869021018925545016502e-01,
+ -2.517729313893103197176091e-01,
+ -7.39241351595676573201918e-01,
+}
+
+// Results for 100000 * Pi + vf[i]
+var cosLarge = []float64{
+ 2.634752141185559426744e-01,
+ 1.14855126055543100712e-01,
+ 9.61912973266488928113e-01,
+ 2.9381411499556122552e-01,
+ -9.777138189880161924641e-01,
+ -9.76930413445147608049e-01,
+ 4.940088097314976789841e-01,
+ -9.15658690217517835002e-01,
+ -2.51772931436786954751e-01,
+ -7.3924135157173099849e-01,
+}
+
+var cosh = []float64{
+ 7.2668796942212842775517446e+01,
+ 1.1479413465659254502011135e+03,
+ 1.0385767908766418550935495e+00,
+ 7.5000957789658051428857788e+01,
+ 7.655246669605357888468613e+03,
+ 9.3567491758321272072888257e+00,
+ 9.331351599270605471131735e+01,
+ 7.6833430994624643209296404e+00,
+ 3.1829371625150718153881164e+00,
+ 2.9595059261916188501640911e+03,
+}
+var erf = []float64{
+ 5.1865354817738701906913566e-01,
+ 7.2623875834137295116929844e-01,
+ -3.123458688281309990629839e-02,
+ -5.2143121110253302920437013e-01,
+ 8.2704742671312902508629582e-01,
+ 3.2101767558376376743993945e-01,
+ 5.403990312223245516066252e-01,
+ 3.0034702916738588551174831e-01,
+ 2.0369924417882241241559589e-01,
+ -7.8069386968009226729944677e-01,
+}
+var erfc = []float64{
+ 4.8134645182261298093086434e-01,
+ 2.7376124165862704883070156e-01,
+ 1.0312345868828130999062984e+00,
+ 1.5214312111025330292043701e+00,
+ 1.7295257328687097491370418e-01,
+ 6.7898232441623623256006055e-01,
+ 4.596009687776754483933748e-01,
+ 6.9965297083261411448825169e-01,
+ 7.9630075582117758758440411e-01,
+ 1.7806938696800922672994468e+00,
+}
+var erfinv = []float64{
+ 4.746037673358033586786350696e-01,
+ 8.559054432692110956388764172e-01,
+ -2.45427830571707336251331946e-02,
+ -4.78116683518973366268905506e-01,
+ 1.479804430319470983648120853e+00,
+ 2.654485787128896161882650211e-01,
+ 5.027444534221520197823192493e-01,
+ 2.466703532707627818954585670e-01,
+ 1.632011465103005426240343116e-01,
+ -1.06672334642196900710000389e+00,
+}
+var exp = []float64{
+ 1.4533071302642137507696589e+02,
+ 2.2958822575694449002537581e+03,
+ 7.5814542574851666582042306e-01,
+ 6.6668778421791005061482264e-03,
+ 1.5310493273896033740861206e+04,
+ 1.8659907517999328638667732e+01,
+ 1.8662167355098714543942057e+02,
+ 1.5301332413189378961665788e+01,
+ 6.2047063430646876349125085e+00,
+ 1.6894712385826521111610438e-04,
+}
+var expm1 = []float64{
+ 5.105047796122957327384770212e-02,
+ 8.046199708567344080562675439e-02,
+ -2.764970978891639815187418703e-03,
+ -4.8871434888875355394330300273e-02,
+ 1.0115864277221467777117227494e-01,
+ 2.969616407795910726014621657e-02,
+ 5.368214487944892300914037972e-02,
+ 2.765488851131274068067445335e-02,
+ 1.842068661871398836913874273e-02,
+ -8.3193870863553801814961137573e-02,
+}
+var expm1Large = []float64{
+ 4.2031418113550844e+21,
+ 4.0690789717473863e+33,
+ -0.9372627915981363e+00,
+ -1.0,
+ 7.077694784145933e+41,
+ 5.117936223839153e+12,
+ 5.124137759001189e+22,
+ 7.03546003972584e+11,
+ 8.456921800389698e+07,
+ -1.0,
+}
+var exp2 = []float64{
+ 3.1537839463286288034313104e+01,
+ 2.1361549283756232296144849e+02,
+ 8.2537402562185562902577219e-01,
+ 3.1021158628740294833424229e-02,
+ 7.9581744110252191462569661e+02,
+ 7.6019905892596359262696423e+00,
+ 3.7506882048388096973183084e+01,
+ 6.6250893439173561733216375e+00,
+ 3.5438267900243941544605339e+00,
+ 2.4281533133513300984289196e-03,
+}
+var fabs = []float64{
+ 4.9790119248836735e+00,
+ 7.7388724745781045e+00,
+ 2.7688005719200159e-01,
+ 5.0106036182710749e+00,
+ 9.6362937071984173e+00,
+ 2.9263772392439646e+00,
+ 5.2290834314593066e+00,
+ 2.7279399104360102e+00,
+ 1.8253080916808550e+00,
+ 8.6859247685756013e+00,
+}
+var fdim = []float64{
+ 4.9790119248836735e+00,
+ 7.7388724745781045e+00,
+ 0.0000000000000000e+00,
+ 0.0000000000000000e+00,
+ 9.6362937071984173e+00,
+ 2.9263772392439646e+00,
+ 5.2290834314593066e+00,
+ 2.7279399104360102e+00,
+ 1.8253080916808550e+00,
+ 0.0000000000000000e+00,
+}
+var floor = []float64{
+ 4.0000000000000000e+00,
+ 7.0000000000000000e+00,
+ -1.0000000000000000e+00,
+ -6.0000000000000000e+00,
+ 9.0000000000000000e+00,
+ 2.0000000000000000e+00,
+ 5.0000000000000000e+00,
+ 2.0000000000000000e+00,
+ 1.0000000000000000e+00,
+ -9.0000000000000000e+00,
+}
+var fmod = []float64{
+ 4.197615023265299782906368e-02,
+ 2.261127525421895434476482e+00,
+ 3.231794108794261433104108e-02,
+ 4.989396381728925078391512e+00,
+ 3.637062928015826201999516e-01,
+ 1.220868282268106064236690e+00,
+ 4.770916568540693347699744e+00,
+ 1.816180268691969246219742e+00,
+ 8.734595415957246977711748e-01,
+ 1.314075231424398637614104e+00,
+}
+
+type fi struct {
+ f float64
+ i int
+}
+
+var frexp = []fi{
+ {6.2237649061045918750e-01, 3},
+ {9.6735905932226306250e-01, 3},
+ {-5.5376011438400318000e-01, -1},
+ {-6.2632545228388436250e-01, 3},
+ {6.02268356699901081250e-01, 4},
+ {7.3159430981099115000e-01, 2},
+ {6.5363542893241332500e-01, 3},
+ {6.8198497760900255000e-01, 2},
+ {9.1265404584042750000e-01, 1},
+ {-5.4287029803597508250e-01, 4},
+}
+var gamma = []float64{
+ 2.3254348370739963835386613898e+01,
+ 2.991153837155317076427529816e+03,
+ -4.561154336726758060575129109e+00,
+ 7.719403468842639065959210984e-01,
+ 1.6111876618855418534325755566e+05,
+ 1.8706575145216421164173224946e+00,
+ 3.4082787447257502836734201635e+01,
+ 1.579733951448952054898583387e+00,
+ 9.3834586598354592860187267089e-01,
+ -2.093995902923148389186189429e-05,
+}
+var j0 = []float64{
+ -1.8444682230601672018219338e-01,
+ 2.27353668906331975435892e-01,
+ 9.809259936157051116270273e-01,
+ -1.741170131426226587841181e-01,
+ -2.1389448451144143352039069e-01,
+ -2.340905848928038763337414e-01,
+ -1.0029099691890912094586326e-01,
+ -1.5466726714884328135358907e-01,
+ 3.252650187653420388714693e-01,
+ -8.72218484409407250005360235e-03,
+}
+var j1 = []float64{
+ -3.251526395295203422162967e-01,
+ 1.893581711430515718062564e-01,
+ -1.3711761352467242914491514e-01,
+ 3.287486536269617297529617e-01,
+ 1.3133899188830978473849215e-01,
+ 3.660243417832986825301766e-01,
+ -3.4436769271848174665420672e-01,
+ 4.329481396640773768835036e-01,
+ 5.8181350531954794639333955e-01,
+ -2.7030574577733036112996607e-01,
+}
+var j2 = []float64{
+ 5.3837518920137802565192769e-02,
+ -1.7841678003393207281244667e-01,
+ 9.521746934916464142495821e-03,
+ 4.28958355470987397983072e-02,
+ 2.4115371837854494725492872e-01,
+ 4.842458532394520316844449e-01,
+ -3.142145220618633390125946e-02,
+ 4.720849184745124761189957e-01,
+ 3.122312022520957042957497e-01,
+ 7.096213118930231185707277e-02,
+}
+var jM3 = []float64{
+ -3.684042080996403091021151e-01,
+ 2.8157665936340887268092661e-01,
+ 4.401005480841948348343589e-04,
+ 3.629926999056814081597135e-01,
+ 3.123672198825455192489266e-02,
+ -2.958805510589623607540455e-01,
+ -3.2033177696533233403289416e-01,
+ -2.592737332129663376736604e-01,
+ -1.0241334641061485092351251e-01,
+ -2.3762660886100206491674503e-01,
+}
+var lgamma = []fi{
+ {3.146492141244545774319734e+00, 1},
+ {8.003414490659126375852113e+00, 1},
+ {1.517575735509779707488106e+00, -1},
+ {-2.588480028182145853558748e-01, 1},
+ {1.1989897050205555002007985e+01, 1},
+ {6.262899811091257519386906e-01, 1},
+ {3.5287924899091566764846037e+00, 1},
+ {4.5725644770161182299423372e-01, 1},
+ {-6.363667087767961257654854e-02, 1},
+ {-1.077385130910300066425564e+01, -1},
+}
+var log = []float64{
+ 1.605231462693062999102599e+00,
+ 2.0462560018708770653153909e+00,
+ -1.2841708730962657801275038e+00,
+ 1.6115563905281545116286206e+00,
+ 2.2655365644872016636317461e+00,
+ 1.0737652208918379856272735e+00,
+ 1.6542360106073546632707956e+00,
+ 1.0035467127723465801264487e+00,
+ 6.0174879014578057187016475e-01,
+ 2.161703872847352815363655e+00,
+}
+var logb = []float64{
+ 2.0000000000000000e+00,
+ 2.0000000000000000e+00,
+ -2.0000000000000000e+00,
+ 2.0000000000000000e+00,
+ 3.0000000000000000e+00,
+ 1.0000000000000000e+00,
+ 2.0000000000000000e+00,
+ 1.0000000000000000e+00,
+ 0.0000000000000000e+00,
+ 3.0000000000000000e+00,
+}
+var log10 = []float64{
+ 6.9714316642508290997617083e-01,
+ 8.886776901739320576279124e-01,
+ -5.5770832400658929815908236e-01,
+ 6.998900476822994346229723e-01,
+ 9.8391002850684232013281033e-01,
+ 4.6633031029295153334285302e-01,
+ 7.1842557117242328821552533e-01,
+ 4.3583479968917773161304553e-01,
+ 2.6133617905227038228626834e-01,
+ 9.3881606348649405716214241e-01,
+}
+var log1p = []float64{
+ 4.8590257759797794104158205e-02,
+ 7.4540265965225865330849141e-02,
+ -2.7726407903942672823234024e-03,
+ -5.1404917651627649094953380e-02,
+ 9.1998280672258624681335010e-02,
+ 2.8843762576593352865894824e-02,
+ 5.0969534581863707268992645e-02,
+ 2.6913947602193238458458594e-02,
+ 1.8088493239630770262045333e-02,
+ -9.0865245631588989681559268e-02,
+}
+var log2 = []float64{
+ 2.3158594707062190618898251e+00,
+ 2.9521233862883917703341018e+00,
+ -1.8526669502700329984917062e+00,
+ 2.3249844127278861543568029e+00,
+ 3.268478366538305087466309e+00,
+ 1.5491157592596970278166492e+00,
+ 2.3865580889631732407886495e+00,
+ 1.447811865817085365540347e+00,
+ 8.6813999540425116282815557e-01,
+ 3.118679457227342224364709e+00,
+}
+var modf = [][2]float64{
+ {4.0000000000000000e+00, 9.7901192488367350108546816e-01},
+ {7.0000000000000000e+00, 7.3887247457810456552351752e-01},
+ {Copysign(0, -1), -2.7688005719200159404635997e-01},
+ {-5.0000000000000000e+00, -1.060361827107492160848778e-02},
+ {9.0000000000000000e+00, 6.3629370719841737980004837e-01},
+ {2.0000000000000000e+00, 9.2637723924396464525443662e-01},
+ {5.0000000000000000e+00, 2.2908343145930665230025625e-01},
+ {2.0000000000000000e+00, 7.2793991043601025126008608e-01},
+ {1.0000000000000000e+00, 8.2530809168085506044576505e-01},
+ {-8.0000000000000000e+00, -6.8592476857560136238589621e-01},
+}
+var nextafter32 = []float32{
+ 4.979012489318848e+00,
+ 7.738873004913330e+00,
+ -2.768800258636475e-01,
+ -5.010602951049805e+00,
+ 9.636294364929199e+00,
+ 2.926377534866333e+00,
+ 5.229084014892578e+00,
+ 2.727940082550049e+00,
+ 1.825308203697205e+00,
+ -8.685923576354980e+00,
+}
+var nextafter64 = []float64{
+ 4.97901192488367438926388786e+00,
+ 7.73887247457810545370193722e+00,
+ -2.7688005719200153853520874e-01,
+ -5.01060361827107403343006808e+00,
+ 9.63629370719841915615688777e+00,
+ 2.92637723924396508934364647e+00,
+ 5.22908343145930754047867595e+00,
+ 2.72793991043601069534929593e+00,
+ 1.82530809168085528249036997e+00,
+ -8.68592476857559958602905681e+00,
+}
+var pow = []float64{
+ 9.5282232631648411840742957e+04,
+ 5.4811599352999901232411871e+07,
+ 5.2859121715894396531132279e-01,
+ 9.7587991957286474464259698e-06,
+ 4.328064329346044846740467e+09,
+ 8.4406761805034547437659092e+02,
+ 1.6946633276191194947742146e+05,
+ 5.3449040147551939075312879e+02,
+ 6.688182138451414936380374e+01,
+ 2.0609869004248742886827439e-09,
+}
+var remainder = []float64{
+ 4.197615023265299782906368e-02,
+ 2.261127525421895434476482e+00,
+ 3.231794108794261433104108e-02,
+ -2.120723654214984321697556e-02,
+ 3.637062928015826201999516e-01,
+ 1.220868282268106064236690e+00,
+ -4.581668629186133046005125e-01,
+ -9.117596417440410050403443e-01,
+ 8.734595415957246977711748e-01,
+ 1.314075231424398637614104e+00,
+}
+var round = []float64{
+ 5,
+ 8,
+ Copysign(0, -1),
+ -5,
+ 10,
+ 3,
+ 5,
+ 3,
+ 2,
+ -9,
+}
+var signbit = []bool{
+ false,
+ false,
+ true,
+ true,
+ false,
+ false,
+ false,
+ false,
+ false,
+ true,
+}
+var sin = []float64{
+ -9.6466616586009283766724726e-01,
+ 9.9338225271646545763467022e-01,
+ -2.7335587039794393342449301e-01,
+ 9.5586257685042792878173752e-01,
+ -2.099421066779969164496634e-01,
+ 2.135578780799860532750616e-01,
+ -8.694568971167362743327708e-01,
+ 4.019566681155577786649878e-01,
+ 9.6778633541687993721617774e-01,
+ -6.734405869050344734943028e-01,
+}
+
+// Results for 100000 * Pi + vf[i]
+var sinLarge = []float64{
+ -9.646661658548936063912e-01,
+ 9.933822527198506903752e-01,
+ -2.7335587036246899796e-01,
+ 9.55862576853689321268e-01,
+ -2.099421066862688873691e-01,
+ 2.13557878070308981163e-01,
+ -8.694568970959221300497e-01,
+ 4.01956668098863248917e-01,
+ 9.67786335404528727927e-01,
+ -6.7344058693131973066e-01,
+}
+var sinh = []float64{
+ 7.2661916084208532301448439e+01,
+ 1.1479409110035194500526446e+03,
+ -2.8043136512812518927312641e-01,
+ -7.499429091181587232835164e+01,
+ 7.6552466042906758523925934e+03,
+ 9.3031583421672014313789064e+00,
+ 9.330815755828109072810322e+01,
+ 7.6179893137269146407361477e+00,
+ 3.021769180549615819524392e+00,
+ -2.95950575724449499189888e+03,
+}
+var sqrt = []float64{
+ 2.2313699659365484748756904e+00,
+ 2.7818829009464263511285458e+00,
+ 5.2619393496314796848143251e-01,
+ 2.2384377628763938724244104e+00,
+ 3.1042380236055381099288487e+00,
+ 1.7106657298385224403917771e+00,
+ 2.286718922705479046148059e+00,
+ 1.6516476350711159636222979e+00,
+ 1.3510396336454586262419247e+00,
+ 2.9471892997524949215723329e+00,
+}
+var tan = []float64{
+ -3.661316565040227801781974e+00,
+ 8.64900232648597589369854e+00,
+ -2.8417941955033612725238097e-01,
+ 3.253290185974728640827156e+00,
+ 2.147275640380293804770778e-01,
+ -2.18600910711067004921551e-01,
+ -1.760002817872367935518928e+00,
+ -4.389808914752818126249079e-01,
+ -3.843885560201130679995041e+00,
+ 9.10988793377685105753416e-01,
+}
+
+// Results for 100000 * Pi + vf[i]
+var tanLarge = []float64{
+ -3.66131656475596512705e+00,
+ 8.6490023287202547927e+00,
+ -2.841794195104782406e-01,
+ 3.2532901861033120983e+00,
+ 2.14727564046880001365e-01,
+ -2.18600910700688062874e-01,
+ -1.760002817699722747043e+00,
+ -4.38980891453536115952e-01,
+ -3.84388555942723509071e+00,
+ 9.1098879344275101051e-01,
+}
+var tanh = []float64{
+ 9.9990531206936338549262119e-01,
+ 9.9999962057085294197613294e-01,
+ -2.7001505097318677233756845e-01,
+ -9.9991110943061718603541401e-01,
+ 9.9999999146798465745022007e-01,
+ 9.9427249436125236705001048e-01,
+ 9.9994257600983138572705076e-01,
+ 9.9149409509772875982054701e-01,
+ 9.4936501296239685514466577e-01,
+ -9.9999994291374030946055701e-01,
+}
+var trunc = []float64{
+ 4.0000000000000000e+00,
+ 7.0000000000000000e+00,
+ Copysign(0, -1),
+ -5.0000000000000000e+00,
+ 9.0000000000000000e+00,
+ 2.0000000000000000e+00,
+ 5.0000000000000000e+00,
+ 2.0000000000000000e+00,
+ 1.0000000000000000e+00,
+ -8.0000000000000000e+00,
+}
+var y0 = []float64{
+ -3.053399153780788357534855e-01,
+ 1.7437227649515231515503649e-01,
+ -8.6221781263678836910392572e-01,
+ -3.100664880987498407872839e-01,
+ 1.422200649300982280645377e-01,
+ 4.000004067997901144239363e-01,
+ -3.3340749753099352392332536e-01,
+ 4.5399790746668954555205502e-01,
+ 4.8290004112497761007536522e-01,
+ 2.7036697826604756229601611e-01,
+}
+var y1 = []float64{
+ 0.15494213737457922210218611,
+ -0.2165955142081145245075746,
+ -2.4644949631241895201032829,
+ 0.1442740489541836405154505,
+ 0.2215379960518984777080163,
+ 0.3038800915160754150565448,
+ 0.0691107642452362383808547,
+ 0.2380116417809914424860165,
+ -0.20849492979459761009678934,
+ 0.0242503179793232308250804,
+}
+var y2 = []float64{
+ 0.3675780219390303613394936,
+ -0.23034826393250119879267257,
+ -16.939677983817727205631397,
+ 0.367653980523052152867791,
+ -0.0962401471767804440353136,
+ -0.1923169356184851105200523,
+ 0.35984072054267882391843766,
+ -0.2794987252299739821654982,
+ -0.7113490692587462579757954,
+ -0.2647831587821263302087457,
+}
+var yM3 = []float64{
+ -0.14035984421094849100895341,
+ -0.097535139617792072703973,
+ 242.25775994555580176377379,
+ -0.1492267014802818619511046,
+ 0.26148702629155918694500469,
+ 0.56675383593895176530394248,
+ -0.206150264009006981070575,
+ 0.64784284687568332737963658,
+ 1.3503631555901938037008443,
+ 0.1461869756579956803341844,
+}
+
+// arguments and expected results for special cases
+var vfacosSC = []float64{
+ -Pi,
+ 1,
+ Pi,
+ NaN(),
+}
+var acosSC = []float64{
+ NaN(),
+ 0,
+ NaN(),
+ NaN(),
+}
+
+var vfacoshSC = []float64{
+ Inf(-1),
+ 0.5,
+ 1,
+ Inf(1),
+ NaN(),
+}
+var acoshSC = []float64{
+ NaN(),
+ NaN(),
+ 0,
+ Inf(1),
+ NaN(),
+}
+
+var vfasinSC = []float64{
+ -Pi,
+ Copysign(0, -1),
+ 0,
+ Pi,
+ NaN(),
+}
+var asinSC = []float64{
+ NaN(),
+ Copysign(0, -1),
+ 0,
+ NaN(),
+ NaN(),
+}
+
+var vfasinhSC = []float64{
+ Inf(-1),
+ Copysign(0, -1),
+ 0,
+ Inf(1),
+ NaN(),
+}
+var asinhSC = []float64{
+ Inf(-1),
+ Copysign(0, -1),
+ 0,
+ Inf(1),
+ NaN(),
+}
+
+var vfatanSC = []float64{
+ Inf(-1),
+ Copysign(0, -1),
+ 0,
+ Inf(1),
+ NaN(),
+}
+var atanSC = []float64{
+ -Pi / 2,
+ Copysign(0, -1),
+ 0,
+ Pi / 2,
+ NaN(),
+}
+
+var vfatanhSC = []float64{
+ Inf(-1),
+ -Pi,
+ -1,
+ Copysign(0, -1),
+ 0,
+ 1,
+ Pi,
+ Inf(1),
+ NaN(),
+}
+var atanhSC = []float64{
+ NaN(),
+ NaN(),
+ Inf(-1),
+ Copysign(0, -1),
+ 0,
+ Inf(1),
+ NaN(),
+ NaN(),
+ NaN(),
+}
+var vfatan2SC = [][2]float64{
+ {Inf(-1), Inf(-1)},
+ {Inf(-1), -Pi},
+ {Inf(-1), 0},
+ {Inf(-1), +Pi},
+ {Inf(-1), Inf(1)},
+ {Inf(-1), NaN()},
+ {-Pi, Inf(-1)},
+ {-Pi, 0},
+ {-Pi, Inf(1)},
+ {-Pi, NaN()},
+ {Copysign(0, -1), Inf(-1)},
+ {Copysign(0, -1), -Pi},
+ {Copysign(0, -1), Copysign(0, -1)},
+ {Copysign(0, -1), 0},
+ {Copysign(0, -1), +Pi},
+ {Copysign(0, -1), Inf(1)},
+ {Copysign(0, -1), NaN()},
+ {0, Inf(-1)},
+ {0, -Pi},
+ {0, Copysign(0, -1)},
+ {0, 0},
+ {0, +Pi},
+ {0, Inf(1)},
+ {0, NaN()},
+ {+Pi, Inf(-1)},
+ {+Pi, 0},
+ {+Pi, Inf(1)},
+ {1.0, Inf(1)},
+ {-1.0, Inf(1)},
+ {+Pi, NaN()},
+ {Inf(1), Inf(-1)},
+ {Inf(1), -Pi},
+ {Inf(1), 0},
+ {Inf(1), +Pi},
+ {Inf(1), Inf(1)},
+ {Inf(1), NaN()},
+ {NaN(), NaN()},
+}
+var atan2SC = []float64{
+ -3 * Pi / 4, // atan2(-Inf, -Inf)
+ -Pi / 2, // atan2(-Inf, -Pi)
+ -Pi / 2, // atan2(-Inf, +0)
+ -Pi / 2, // atan2(-Inf, +Pi)
+ -Pi / 4, // atan2(-Inf, +Inf)
+ NaN(), // atan2(-Inf, NaN)
+ -Pi, // atan2(-Pi, -Inf)
+ -Pi / 2, // atan2(-Pi, +0)
+ Copysign(0, -1), // atan2(-Pi, Inf)
+ NaN(), // atan2(-Pi, NaN)
+ -Pi, // atan2(-0, -Inf)
+ -Pi, // atan2(-0, -Pi)
+ -Pi, // atan2(-0, -0)
+ Copysign(0, -1), // atan2(-0, +0)
+ Copysign(0, -1), // atan2(-0, +Pi)
+ Copysign(0, -1), // atan2(-0, +Inf)
+ NaN(), // atan2(-0, NaN)
+ Pi, // atan2(+0, -Inf)
+ Pi, // atan2(+0, -Pi)
+ Pi, // atan2(+0, -0)
+ 0, // atan2(+0, +0)
+ 0, // atan2(+0, +Pi)
+ 0, // atan2(+0, +Inf)
+ NaN(), // atan2(+0, NaN)
+ Pi, // atan2(+Pi, -Inf)
+ Pi / 2, // atan2(+Pi, +0)
+ 0, // atan2(+Pi, +Inf)
+ 0, // atan2(+1, +Inf)
+ Copysign(0, -1), // atan2(-1, +Inf)
+ NaN(), // atan2(+Pi, NaN)
+ 3 * Pi / 4, // atan2(+Inf, -Inf)
+ Pi / 2, // atan2(+Inf, -Pi)
+ Pi / 2, // atan2(+Inf, +0)
+ Pi / 2, // atan2(+Inf, +Pi)
+ Pi / 4, // atan2(+Inf, +Inf)
+ NaN(), // atan2(+Inf, NaN)
+ NaN(), // atan2(NaN, NaN)
+}
+
+var vfcbrtSC = []float64{
+ Inf(-1),
+ Copysign(0, -1),
+ 0,
+ Inf(1),
+ NaN(),
+}
+var cbrtSC = []float64{
+ Inf(-1),
+ Copysign(0, -1),
+ 0,
+ Inf(1),
+ NaN(),
+}
+
+var vfceilSC = []float64{
+ Inf(-1),
+ Copysign(0, -1),
+ 0,
+ Inf(1),
+ NaN(),
+ 1<<52 - 1,
+ 1<<52 - 0.5, // largest fractional float64
+ 1 << 52,
+ -1 << 52,
+ -1<<52 + 0.5, // smallest fractional float64
+ -1<<52 + 1,
+ 1 << 53,
+ -1 << 53,
+}
+
+var ceilBaseSC = []float64{
+ Inf(-1),
+ Copysign(0, -1),
+ 0,
+ Inf(1),
+ NaN(),
+}
+
+var ceilSC = append(ceilBaseSC,
+ 1<<52-1,
+ 1<<52,
+ 1<<52,
+ -1<<52,
+ -1<<52+1,
+ -1<<52+1,
+ 1<<53,
+ -1<<53,
+)
+
+var floorSC = append(ceilBaseSC,
+ 1<<52-1,
+ 1<<52-1,
+ 1<<52,
+ -1<<52,
+ -1<<52,
+ -1<<52+1,
+ 1<<53,
+ -1<<53,
+)
+
+var truncSC = append(ceilBaseSC,
+ 1<<52-1,
+ 1<<52-1,
+ 1<<52,
+ -1<<52,
+ -1<<52+1,
+ -1<<52+1,
+ 1<<53,
+ -1<<53,
+)
+
+var vfcopysignSC = []float64{
+ Inf(-1),
+ Inf(1),
+ NaN(),
+}
+var copysignSC = []float64{
+ Inf(-1),
+ Inf(-1),
+ NaN(),
+}
+
+var vfcosSC = []float64{
+ Inf(-1),
+ Inf(1),
+ NaN(),
+}
+var cosSC = []float64{
+ NaN(),
+ NaN(),
+ NaN(),
+}
+
+var vfcoshSC = []float64{
+ Inf(-1),
+ Copysign(0, -1),
+ 0,
+ Inf(1),
+ NaN(),
+}
+var coshSC = []float64{
+ Inf(1),
+ 1,
+ 1,
+ Inf(1),
+ NaN(),
+}
+
+var vferfSC = []float64{
+ Inf(-1),
+ Copysign(0, -1),
+ 0,
+ Inf(1),
+ NaN(),
+ -1000,
+ 1000,
+}
+var erfSC = []float64{
+ -1,
+ Copysign(0, -1),
+ 0,
+ 1,
+ NaN(),
+ -1,
+ 1,
+}
+
+var vferfcSC = []float64{
+ Inf(-1),
+ Inf(1),
+ NaN(),
+ -1000,
+ 1000,
+}
+var erfcSC = []float64{
+ 2,
+ 0,
+ NaN(),
+ 2,
+ 0,
+}
+
+var vferfinvSC = []float64{
+ 1,
+ -1,
+ 0,
+ Inf(-1),
+ Inf(1),
+ NaN(),
+}
+var erfinvSC = []float64{
+ Inf(+1),
+ Inf(-1),
+ 0,
+ NaN(),
+ NaN(),
+ NaN(),
+}
+
+var vferfcinvSC = []float64{
+ 0,
+ 2,
+ 1,
+ Inf(1),
+ Inf(-1),
+ NaN(),
+}
+var erfcinvSC = []float64{
+ Inf(+1),
+ Inf(-1),
+ 0,
+ NaN(),
+ NaN(),
+ NaN(),
+}
+
+var vfexpSC = []float64{
+ Inf(-1),
+ -2000,
+ 2000,
+ Inf(1),
+ NaN(),
+ // smallest float64 that overflows Exp(x)
+ 7.097827128933841e+02,
+ // Issue 18912
+ 1.48852223e+09,
+ 1.4885222e+09,
+ 1,
+ // near zero
+ 3.725290298461915e-09,
+ // denormal
+ -740,
+}
+var expSC = []float64{
+ 0,
+ 0,
+ Inf(1),
+ Inf(1),
+ NaN(),
+ Inf(1),
+ Inf(1),
+ Inf(1),
+ 2.718281828459045,
+ 1.0000000037252903,
+ 4.2e-322,
+}
+
+var vfexp2SC = []float64{
+ Inf(-1),
+ -2000,
+ 2000,
+ Inf(1),
+ NaN(),
+ // smallest float64 that overflows Exp2(x)
+ 1024,
+ // near underflow
+ -1.07399999999999e+03,
+ // near zero
+ 3.725290298461915e-09,
+}
+var exp2SC = []float64{
+ 0,
+ 0,
+ Inf(1),
+ Inf(1),
+ NaN(),
+ Inf(1),
+ 5e-324,
+ 1.0000000025821745,
+}
+
+var vfexpm1SC = []float64{
+ Inf(-1),
+ -710,
+ Copysign(0, -1),
+ 0,
+ 710,
+ Inf(1),
+ NaN(),
+}
+var expm1SC = []float64{
+ -1,
+ -1,
+ Copysign(0, -1),
+ 0,
+ Inf(1),
+ Inf(1),
+ NaN(),
+}
+
+var vffabsSC = []float64{
+ Inf(-1),
+ Copysign(0, -1),
+ 0,
+ Inf(1),
+ NaN(),
+}
+var fabsSC = []float64{
+ Inf(1),
+ 0,
+ 0,
+ Inf(1),
+ NaN(),
+}
+
+var vffdimSC = [][2]float64{
+ {Inf(-1), Inf(-1)},
+ {Inf(-1), Inf(1)},
+ {Inf(-1), NaN()},
+ {Copysign(0, -1), Copysign(0, -1)},
+ {Copysign(0, -1), 0},
+ {0, Copysign(0, -1)},
+ {0, 0},
+ {Inf(1), Inf(-1)},
+ {Inf(1), Inf(1)},
+ {Inf(1), NaN()},
+ {NaN(), Inf(-1)},
+ {NaN(), Copysign(0, -1)},
+ {NaN(), 0},
+ {NaN(), Inf(1)},
+ {NaN(), NaN()},
+}
+var nan = Float64frombits(0xFFF8000000000000) // SSE2 DIVSD 0/0
+var vffdim2SC = [][2]float64{
+ {Inf(-1), Inf(-1)},
+ {Inf(-1), Inf(1)},
+ {Inf(-1), nan},
+ {Copysign(0, -1), Copysign(0, -1)},
+ {Copysign(0, -1), 0},
+ {0, Copysign(0, -1)},
+ {0, 0},
+ {Inf(1), Inf(-1)},
+ {Inf(1), Inf(1)},
+ {Inf(1), nan},
+ {nan, Inf(-1)},
+ {nan, Copysign(0, -1)},
+ {nan, 0},
+ {nan, Inf(1)},
+ {nan, nan},
+}
+var fdimSC = []float64{
+ NaN(),
+ 0,
+ NaN(),
+ 0,
+ 0,
+ 0,
+ 0,
+ Inf(1),
+ NaN(),
+ NaN(),
+ NaN(),
+ NaN(),
+ NaN(),
+ NaN(),
+ NaN(),
+}
+var fmaxSC = []float64{
+ Inf(-1),
+ Inf(1),
+ NaN(),
+ Copysign(0, -1),
+ 0,
+ 0,
+ 0,
+ Inf(1),
+ Inf(1),
+ Inf(1),
+ NaN(),
+ NaN(),
+ NaN(),
+ Inf(1),
+ NaN(),
+}
+var fminSC = []float64{
+ Inf(-1),
+ Inf(-1),
+ Inf(-1),
+ Copysign(0, -1),
+ Copysign(0, -1),
+ Copysign(0, -1),
+ 0,
+ Inf(-1),
+ Inf(1),
+ NaN(),
+ Inf(-1),
+ NaN(),
+ NaN(),
+ NaN(),
+ NaN(),
+}
+
+var vffmodSC = [][2]float64{
+ {Inf(-1), Inf(-1)},
+ {Inf(-1), -Pi},
+ {Inf(-1), 0},
+ {Inf(-1), Pi},
+ {Inf(-1), Inf(1)},
+ {Inf(-1), NaN()},
+ {-Pi, Inf(-1)},
+ {-Pi, 0},
+ {-Pi, Inf(1)},
+ {-Pi, NaN()},
+ {Copysign(0, -1), Inf(-1)},
+ {Copysign(0, -1), 0},
+ {Copysign(0, -1), Inf(1)},
+ {Copysign(0, -1), NaN()},
+ {0, Inf(-1)},
+ {0, 0},
+ {0, Inf(1)},
+ {0, NaN()},
+ {Pi, Inf(-1)},
+ {Pi, 0},
+ {Pi, Inf(1)},
+ {Pi, NaN()},
+ {Inf(1), Inf(-1)},
+ {Inf(1), -Pi},
+ {Inf(1), 0},
+ {Inf(1), Pi},
+ {Inf(1), Inf(1)},
+ {Inf(1), NaN()},
+ {NaN(), Inf(-1)},
+ {NaN(), -Pi},
+ {NaN(), 0},
+ {NaN(), Pi},
+ {NaN(), Inf(1)},
+ {NaN(), NaN()},
+}
+var fmodSC = []float64{
+ NaN(), // fmod(-Inf, -Inf)
+ NaN(), // fmod(-Inf, -Pi)
+ NaN(), // fmod(-Inf, 0)
+ NaN(), // fmod(-Inf, Pi)
+ NaN(), // fmod(-Inf, +Inf)
+ NaN(), // fmod(-Inf, NaN)
+ -Pi, // fmod(-Pi, -Inf)
+ NaN(), // fmod(-Pi, 0)
+ -Pi, // fmod(-Pi, +Inf)
+ NaN(), // fmod(-Pi, NaN)
+ Copysign(0, -1), // fmod(-0, -Inf)
+ NaN(), // fmod(-0, 0)
+ Copysign(0, -1), // fmod(-0, Inf)
+ NaN(), // fmod(-0, NaN)
+ 0, // fmod(0, -Inf)
+ NaN(), // fmod(0, 0)
+ 0, // fmod(0, +Inf)
+ NaN(), // fmod(0, NaN)
+ Pi, // fmod(Pi, -Inf)
+ NaN(), // fmod(Pi, 0)
+ Pi, // fmod(Pi, +Inf)
+ NaN(), // fmod(Pi, NaN)
+ NaN(), // fmod(+Inf, -Inf)
+ NaN(), // fmod(+Inf, -Pi)
+ NaN(), // fmod(+Inf, 0)
+ NaN(), // fmod(+Inf, Pi)
+ NaN(), // fmod(+Inf, +Inf)
+ NaN(), // fmod(+Inf, NaN)
+ NaN(), // fmod(NaN, -Inf)
+ NaN(), // fmod(NaN, -Pi)
+ NaN(), // fmod(NaN, 0)
+ NaN(), // fmod(NaN, Pi)
+ NaN(), // fmod(NaN, +Inf)
+ NaN(), // fmod(NaN, NaN)
+}
+
+var vffrexpSC = []float64{
+ Inf(-1),
+ Copysign(0, -1),
+ 0,
+ Inf(1),
+ NaN(),
+}
+var frexpSC = []fi{
+ {Inf(-1), 0},
+ {Copysign(0, -1), 0},
+ {0, 0},
+ {Inf(1), 0},
+ {NaN(), 0},
+}
+
+var vfgamma = [][2]float64{
+ {Inf(1), Inf(1)},
+ {Inf(-1), NaN()},
+ {0, Inf(1)},
+ {Copysign(0, -1), Inf(-1)},
+ {NaN(), NaN()},
+ {-1, NaN()},
+ {-2, NaN()},
+ {-3, NaN()},
+ {-1e16, NaN()},
+ {-1e300, NaN()},
+ {1.7e308, Inf(1)},
+
+ // Test inputs inspired by Python test suite.
+ // Outputs computed at high precision by PARI/GP.
+ // If recomputing table entries, be careful to use
+ // high-precision (%.1000g) formatting of the float64 inputs.
+ // For example, -2.0000000000000004 is the float64 with exact value
+ // -2.00000000000000044408920985626161695, and
+ // gamma(-2.0000000000000004) = -1249999999999999.5386078562728167651513, while
+ // gamma(-2.00000000000000044408920985626161695) = -1125899906826907.2044875028130093136826.
+ // Thus the table lists -1.1258999068426235e+15 as the answer.
+ {0.5, 1.772453850905516},
+ {1.5, 0.886226925452758},
+ {2.5, 1.329340388179137},
+ {3.5, 3.3233509704478426},
+ {-0.5, -3.544907701811032},
+ {-1.5, 2.363271801207355},
+ {-2.5, -0.9453087204829419},
+ {-3.5, 0.2700882058522691},
+ {0.1, 9.51350769866873},
+ {0.01, 99.4325851191506},
+ {1e-08, 9.999999942278434e+07},
+ {1e-16, 1e+16},
+ {0.001, 999.4237724845955},
+ {1e-16, 1e+16},
+ {1e-308, 1e+308},
+ {5.6e-309, 1.7857142857142864e+308},
+ {5.5e-309, Inf(1)},
+ {1e-309, Inf(1)},
+ {1e-323, Inf(1)},
+ {5e-324, Inf(1)},
+ {-0.1, -10.686287021193193},
+ {-0.01, -100.58719796441078},
+ {-1e-08, -1.0000000057721567e+08},
+ {-1e-16, -1e+16},
+ {-0.001, -1000.5782056293586},
+ {-1e-16, -1e+16},
+ {-1e-308, -1e+308},
+ {-5.6e-309, -1.7857142857142864e+308},
+ {-5.5e-309, Inf(-1)},
+ {-1e-309, Inf(-1)},
+ {-1e-323, Inf(-1)},
+ {-5e-324, Inf(-1)},
+ {-0.9999999999999999, -9.007199254740992e+15},
+ {-1.0000000000000002, 4.5035996273704955e+15},
+ {-1.9999999999999998, 2.2517998136852485e+15},
+ {-2.0000000000000004, -1.1258999068426235e+15},
+ {-100.00000000000001, -7.540083334883109e-145},
+ {-99.99999999999999, 7.540083334884096e-145},
+ {17, 2.0922789888e+13},
+ {171, 7.257415615307999e+306},
+ {171.6, 1.5858969096672565e+308},
+ {171.624, 1.7942117599248104e+308},
+ {171.625, Inf(1)},
+ {172, Inf(1)},
+ {2000, Inf(1)},
+ {-100.5, -3.3536908198076787e-159},
+ {-160.5, -5.255546447007829e-286},
+ {-170.5, -3.3127395215386074e-308},
+ {-171.5, 1.9316265431712e-310},
+ {-176.5, -1.196e-321},
+ {-177.5, 5e-324},
+ {-178.5, Copysign(0, -1)},
+ {-179.5, 0},
+ {-201.0001, 0},
+ {-202.9999, Copysign(0, -1)},
+ {-1000.5, Copysign(0, -1)},
+ {-1.0000000003e+09, Copysign(0, -1)},
+ {-4.5035996273704955e+15, 0},
+ {-63.349078729022985, 4.177797167776188e-88},
+ {-127.45117632943295, 1.183111089623681e-214},
+}
+
+var vfhypotSC = [][2]float64{
+ {Inf(-1), Inf(-1)},
+ {Inf(-1), 0},
+ {Inf(-1), Inf(1)},
+ {Inf(-1), NaN()},
+ {Copysign(0, -1), Copysign(0, -1)},
+ {Copysign(0, -1), 0},
+ {0, Copysign(0, -1)},
+ {0, 0}, // +0, +0
+ {0, Inf(-1)},
+ {0, Inf(1)},
+ {0, NaN()},
+ {Inf(1), Inf(-1)},
+ {Inf(1), 0},
+ {Inf(1), Inf(1)},
+ {Inf(1), NaN()},
+ {NaN(), Inf(-1)},
+ {NaN(), 0},
+ {NaN(), Inf(1)},
+ {NaN(), NaN()},
+}
+var hypotSC = []float64{
+ Inf(1),
+ Inf(1),
+ Inf(1),
+ Inf(1),
+ 0,
+ 0,
+ 0,
+ 0,
+ Inf(1),
+ Inf(1),
+ NaN(),
+ Inf(1),
+ Inf(1),
+ Inf(1),
+ Inf(1),
+ Inf(1),
+ NaN(),
+ Inf(1),
+ NaN(),
+}
+
+var ilogbSC = []int{
+ MaxInt32,
+ MinInt32,
+ MaxInt32,
+ MaxInt32,
+}
+
+var vfj0SC = []float64{
+ Inf(-1),
+ 0,
+ Inf(1),
+ NaN(),
+}
+var j0SC = []float64{
+ 0,
+ 1,
+ 0,
+ NaN(),
+}
+var j1SC = []float64{
+ 0,
+ 0,
+ 0,
+ NaN(),
+}
+var j2SC = []float64{
+ 0,
+ 0,
+ 0,
+ NaN(),
+}
+var jM3SC = []float64{
+ 0,
+ 0,
+ 0,
+ NaN(),
+}
+
+var vfldexpSC = []fi{
+ {0, 0},
+ {0, -1075},
+ {0, 1024},
+ {Copysign(0, -1), 0},
+ {Copysign(0, -1), -1075},
+ {Copysign(0, -1), 1024},
+ {Inf(1), 0},
+ {Inf(1), -1024},
+ {Inf(-1), 0},
+ {Inf(-1), -1024},
+ {NaN(), -1024},
+ {10, int(1) << (uint64(unsafe.Sizeof(0)-1) * 8)},
+ {10, -(int(1) << (uint64(unsafe.Sizeof(0)-1) * 8))},
+}
+var ldexpSC = []float64{
+ 0,
+ 0,
+ 0,
+ Copysign(0, -1),
+ Copysign(0, -1),
+ Copysign(0, -1),
+ Inf(1),
+ Inf(1),
+ Inf(-1),
+ Inf(-1),
+ NaN(),
+ Inf(1),
+ 0,
+}
+
+var vflgammaSC = []float64{
+ Inf(-1),
+ -3,
+ 0,
+ 1,
+ 2,
+ Inf(1),
+ NaN(),
+}
+var lgammaSC = []fi{
+ {Inf(-1), 1},
+ {Inf(1), 1},
+ {Inf(1), 1},
+ {0, 1},
+ {0, 1},
+ {Inf(1), 1},
+ {NaN(), 1},
+}
+
+var vflogSC = []float64{
+ Inf(-1),
+ -Pi,
+ Copysign(0, -1),
+ 0,
+ 1,
+ Inf(1),
+ NaN(),
+}
+var logSC = []float64{
+ NaN(),
+ NaN(),
+ Inf(-1),
+ Inf(-1),
+ 0,
+ Inf(1),
+ NaN(),
+}
+
+var vflogbSC = []float64{
+ Inf(-1),
+ 0,
+ Inf(1),
+ NaN(),
+}
+var logbSC = []float64{
+ Inf(1),
+ Inf(-1),
+ Inf(1),
+ NaN(),
+}
+
+var vflog1pSC = []float64{
+ Inf(-1),
+ -Pi,
+ -1,
+ Copysign(0, -1),
+ 0,
+ Inf(1),
+ NaN(),
+ 4503599627370496.5, // Issue #29488
+}
+var log1pSC = []float64{
+ NaN(),
+ NaN(),
+ Inf(-1),
+ Copysign(0, -1),
+ 0,
+ Inf(1),
+ NaN(),
+ 36.04365338911715, // Issue #29488
+}
+
+var vfmodfSC = []float64{
+ Inf(-1),
+ Copysign(0, -1),
+ Inf(1),
+ NaN(),
+}
+var modfSC = [][2]float64{
+ {Inf(-1), NaN()}, // [2]float64{Copysign(0, -1), Inf(-1)},
+ {Copysign(0, -1), Copysign(0, -1)},
+ {Inf(1), NaN()}, // [2]float64{0, Inf(1)},
+ {NaN(), NaN()},
+}
+
+var vfnextafter32SC = [][2]float32{
+ {0, 0},
+ {0, float32(Copysign(0, -1))},
+ {0, -1},
+ {0, float32(NaN())},
+ {float32(Copysign(0, -1)), 1},
+ {float32(Copysign(0, -1)), 0},
+ {float32(Copysign(0, -1)), float32(Copysign(0, -1))},
+ {float32(Copysign(0, -1)), -1},
+ {float32(NaN()), 0},
+ {float32(NaN()), float32(NaN())},
+}
+var nextafter32SC = []float32{
+ 0,
+ 0,
+ -1.401298464e-45, // Float32frombits(0x80000001)
+ float32(NaN()),
+ 1.401298464e-45, // Float32frombits(0x00000001)
+ float32(Copysign(0, -1)),
+ float32(Copysign(0, -1)),
+ -1.401298464e-45, // Float32frombits(0x80000001)
+ float32(NaN()),
+ float32(NaN()),
+}
+
+var vfnextafter64SC = [][2]float64{
+ {0, 0},
+ {0, Copysign(0, -1)},
+ {0, -1},
+ {0, NaN()},
+ {Copysign(0, -1), 1},
+ {Copysign(0, -1), 0},
+ {Copysign(0, -1), Copysign(0, -1)},
+ {Copysign(0, -1), -1},
+ {NaN(), 0},
+ {NaN(), NaN()},
+}
+var nextafter64SC = []float64{
+ 0,
+ 0,
+ -4.9406564584124654418e-324, // Float64frombits(0x8000000000000001)
+ NaN(),
+ 4.9406564584124654418e-324, // Float64frombits(0x0000000000000001)
+ Copysign(0, -1),
+ Copysign(0, -1),
+ -4.9406564584124654418e-324, // Float64frombits(0x8000000000000001)
+ NaN(),
+ NaN(),
+}
+
+var vfpowSC = [][2]float64{
+ {Inf(-1), -Pi},
+ {Inf(-1), -3},
+ {Inf(-1), Copysign(0, -1)},
+ {Inf(-1), 0},
+ {Inf(-1), 1},
+ {Inf(-1), 3},
+ {Inf(-1), Pi},
+ {Inf(-1), 0.5},
+ {Inf(-1), NaN()},
+
+ {-Pi, Inf(-1)},
+ {-Pi, -Pi},
+ {-Pi, Copysign(0, -1)},
+ {-Pi, 0},
+ {-Pi, 1},
+ {-Pi, Pi},
+ {-Pi, Inf(1)},
+ {-Pi, NaN()},
+
+ {-1, Inf(-1)},
+ {-1, Inf(1)},
+ {-1, NaN()},
+ {-0.5, Inf(-1)},
+ {-0.5, Inf(1)},
+ {Copysign(0, -1), Inf(-1)},
+ {Copysign(0, -1), -Pi},
+ {Copysign(0, -1), -0.5},
+ {Copysign(0, -1), -3},
+ {Copysign(0, -1), 3},
+ {Copysign(0, -1), Pi},
+ {Copysign(0, -1), 0.5},
+ {Copysign(0, -1), Inf(1)},
+
+ {0, Inf(-1)},
+ {0, -Pi},
+ {0, -3},
+ {0, Copysign(0, -1)},
+ {0, 0},
+ {0, 3},
+ {0, Pi},
+ {0, Inf(1)},
+ {0, NaN()},
+
+ {0.5, Inf(-1)},
+ {0.5, Inf(1)},
+ {1, Inf(-1)},
+ {1, Inf(1)},
+ {1, NaN()},
+
+ {Pi, Inf(-1)},
+ {Pi, Copysign(0, -1)},
+ {Pi, 0},
+ {Pi, 1},
+ {Pi, Inf(1)},
+ {Pi, NaN()},
+ {Inf(1), -Pi},
+ {Inf(1), Copysign(0, -1)},
+ {Inf(1), 0},
+ {Inf(1), 1},
+ {Inf(1), Pi},
+ {Inf(1), NaN()},
+ {NaN(), -Pi},
+ {NaN(), Copysign(0, -1)},
+ {NaN(), 0},
+ {NaN(), 1},
+ {NaN(), Pi},
+ {NaN(), NaN()},
+
+ // Issue #7394 overflow checks
+ {2, float64(1 << 32)},
+ {2, -float64(1 << 32)},
+ {-2, float64(1<<32 + 1)},
+ {0.5, float64(1 << 45)},
+ {0.5, -float64(1 << 45)},
+ {Nextafter(1, 2), float64(1 << 63)},
+ {Nextafter(1, -2), float64(1 << 63)},
+ {Nextafter(-1, 2), float64(1 << 63)},
+ {Nextafter(-1, -2), float64(1 << 63)},
+
+ // Issue #57465
+ {Copysign(0, -1), 1e19},
+ {Copysign(0, -1), -1e19},
+ {Copysign(0, -1), 1<<53 - 1},
+ {Copysign(0, -1), -(1<<53 - 1)},
+}
+var powSC = []float64{
+ 0, // pow(-Inf, -Pi)
+ Copysign(0, -1), // pow(-Inf, -3)
+ 1, // pow(-Inf, -0)
+ 1, // pow(-Inf, +0)
+ Inf(-1), // pow(-Inf, 1)
+ Inf(-1), // pow(-Inf, 3)
+ Inf(1), // pow(-Inf, Pi)
+ Inf(1), // pow(-Inf, 0.5)
+ NaN(), // pow(-Inf, NaN)
+ 0, // pow(-Pi, -Inf)
+ NaN(), // pow(-Pi, -Pi)
+ 1, // pow(-Pi, -0)
+ 1, // pow(-Pi, +0)
+ -Pi, // pow(-Pi, 1)
+ NaN(), // pow(-Pi, Pi)
+ Inf(1), // pow(-Pi, +Inf)
+ NaN(), // pow(-Pi, NaN)
+ 1, // pow(-1, -Inf) IEEE 754-2008
+ 1, // pow(-1, +Inf) IEEE 754-2008
+ NaN(), // pow(-1, NaN)
+ Inf(1), // pow(-1/2, -Inf)
+ 0, // pow(-1/2, +Inf)
+ Inf(1), // pow(-0, -Inf)
+ Inf(1), // pow(-0, -Pi)
+ Inf(1), // pow(-0, -0.5)
+ Inf(-1), // pow(-0, -3) IEEE 754-2008
+ Copysign(0, -1), // pow(-0, 3) IEEE 754-2008
+ 0, // pow(-0, +Pi)
+ 0, // pow(-0, 0.5)
+ 0, // pow(-0, +Inf)
+ Inf(1), // pow(+0, -Inf)
+ Inf(1), // pow(+0, -Pi)
+ Inf(1), // pow(+0, -3)
+ 1, // pow(+0, -0)
+ 1, // pow(+0, +0)
+ 0, // pow(+0, 3)
+ 0, // pow(+0, +Pi)
+ 0, // pow(+0, +Inf)
+ NaN(), // pow(+0, NaN)
+ Inf(1), // pow(1/2, -Inf)
+ 0, // pow(1/2, +Inf)
+ 1, // pow(1, -Inf) IEEE 754-2008
+ 1, // pow(1, +Inf) IEEE 754-2008
+ 1, // pow(1, NaN) IEEE 754-2008
+ 0, // pow(+Pi, -Inf)
+ 1, // pow(+Pi, -0)
+ 1, // pow(+Pi, +0)
+ Pi, // pow(+Pi, 1)
+ Inf(1), // pow(+Pi, +Inf)
+ NaN(), // pow(+Pi, NaN)
+ 0, // pow(+Inf, -Pi)
+ 1, // pow(+Inf, -0)
+ 1, // pow(+Inf, +0)
+ Inf(1), // pow(+Inf, 1)
+ Inf(1), // pow(+Inf, Pi)
+ NaN(), // pow(+Inf, NaN)
+ NaN(), // pow(NaN, -Pi)
+ 1, // pow(NaN, -0)
+ 1, // pow(NaN, +0)
+ NaN(), // pow(NaN, 1)
+ NaN(), // pow(NaN, +Pi)
+ NaN(), // pow(NaN, NaN)
+
+ // Issue #7394 overflow checks
+ Inf(1), // pow(2, float64(1 << 32))
+ 0, // pow(2, -float64(1 << 32))
+ Inf(-1), // pow(-2, float64(1<<32 + 1))
+ 0, // pow(1/2, float64(1 << 45))
+ Inf(1), // pow(1/2, -float64(1 << 45))
+ Inf(1), // pow(Nextafter(1, 2), float64(1 << 63))
+ 0, // pow(Nextafter(1, -2), float64(1 << 63))
+ 0, // pow(Nextafter(-1, 2), float64(1 << 63))
+ Inf(1), // pow(Nextafter(-1, -2), float64(1 << 63))
+
+ // Issue #57465
+ 0, // pow(-0, 1e19)
+ Inf(1), // pow(-0, -1e19)
+ Copysign(0, -1), // pow(-0, 1<<53 -1)
+ Inf(-1), // pow(-0, -(1<<53 -1))
+}
+
+var vfpow10SC = []int{
+ MinInt32,
+ -324,
+ -323,
+ -50,
+ -22,
+ -1,
+ 0,
+ 1,
+ 22,
+ 50,
+ 100,
+ 200,
+ 308,
+ 309,
+ MaxInt32,
+}
+
+var pow10SC = []float64{
+ 0, // pow10(MinInt32)
+ 0, // pow10(-324)
+ 1.0e-323, // pow10(-323)
+ 1.0e-50, // pow10(-50)
+ 1.0e-22, // pow10(-22)
+ 1.0e-1, // pow10(-1)
+ 1.0e0, // pow10(0)
+ 1.0e1, // pow10(1)
+ 1.0e22, // pow10(22)
+ 1.0e50, // pow10(50)
+ 1.0e100, // pow10(100)
+ 1.0e200, // pow10(200)
+ 1.0e308, // pow10(308)
+ Inf(1), // pow10(309)
+ Inf(1), // pow10(MaxInt32)
+}
+
+var vfroundSC = [][2]float64{
+ {0, 0},
+ {1.390671161567e-309, 0}, // denormal
+ {0.49999999999999994, 0}, // 0.5-epsilon
+ {0.5, 1},
+ {0.5000000000000001, 1}, // 0.5+epsilon
+ {-1.5, -2},
+ {-2.5, -3},
+ {NaN(), NaN()},
+ {Inf(1), Inf(1)},
+ {2251799813685249.5, 2251799813685250}, // 1 bit fraction
+ {2251799813685250.5, 2251799813685251},
+ {4503599627370495.5, 4503599627370496}, // 1 bit fraction, rounding to 0 bit fraction
+ {4503599627370497, 4503599627370497}, // large integer
+}
+var vfroundEvenSC = [][2]float64{
+ {0, 0},
+ {1.390671161567e-309, 0}, // denormal
+ {0.49999999999999994, 0}, // 0.5-epsilon
+ {0.5, 0},
+ {0.5000000000000001, 1}, // 0.5+epsilon
+ {-1.5, -2},
+ {-2.5, -2},
+ {NaN(), NaN()},
+ {Inf(1), Inf(1)},
+ {2251799813685249.5, 2251799813685250}, // 1 bit fraction
+ {2251799813685250.5, 2251799813685250},
+ {4503599627370495.5, 4503599627370496}, // 1 bit fraction, rounding to 0 bit fraction
+ {4503599627370497, 4503599627370497}, // large integer
+}
+
+var vfsignbitSC = []float64{
+ Inf(-1),
+ Copysign(0, -1),
+ 0,
+ Inf(1),
+ NaN(),
+}
+var signbitSC = []bool{
+ true,
+ true,
+ false,
+ false,
+ false,
+}
+
+var vfsinSC = []float64{
+ Inf(-1),
+ Copysign(0, -1),
+ 0,
+ Inf(1),
+ NaN(),
+}
+var sinSC = []float64{
+ NaN(),
+ Copysign(0, -1),
+ 0,
+ NaN(),
+ NaN(),
+}
+
+var vfsinhSC = []float64{
+ Inf(-1),
+ Copysign(0, -1),
+ 0,
+ Inf(1),
+ NaN(),
+}
+var sinhSC = []float64{
+ Inf(-1),
+ Copysign(0, -1),
+ 0,
+ Inf(1),
+ NaN(),
+}
+
+var vfsqrtSC = []float64{
+ Inf(-1),
+ -Pi,
+ Copysign(0, -1),
+ 0,
+ Inf(1),
+ NaN(),
+ Float64frombits(2), // subnormal; see https://golang.org/issue/13013
+}
+var sqrtSC = []float64{
+ NaN(),
+ NaN(),
+ Copysign(0, -1),
+ 0,
+ Inf(1),
+ NaN(),
+ 3.1434555694052576e-162,
+}
+
+var vftanhSC = []float64{
+ Inf(-1),
+ Copysign(0, -1),
+ 0,
+ Inf(1),
+ NaN(),
+}
+var tanhSC = []float64{
+ -1,
+ Copysign(0, -1),
+ 0,
+ 1,
+ NaN(),
+}
+
+var vfy0SC = []float64{
+ Inf(-1),
+ 0,
+ Inf(1),
+ NaN(),
+ -1,
+}
+var y0SC = []float64{
+ NaN(),
+ Inf(-1),
+ 0,
+ NaN(),
+ NaN(),
+}
+var y1SC = []float64{
+ NaN(),
+ Inf(-1),
+ 0,
+ NaN(),
+ NaN(),
+}
+var y2SC = []float64{
+ NaN(),
+ Inf(-1),
+ 0,
+ NaN(),
+ NaN(),
+}
+var yM3SC = []float64{
+ NaN(),
+ Inf(1),
+ 0,
+ NaN(),
+ NaN(),
+}
+
+// arguments and expected results for boundary cases
+const (
+ SmallestNormalFloat64 = 2.2250738585072014e-308 // 2**-1022
+ LargestSubnormalFloat64 = SmallestNormalFloat64 - SmallestNonzeroFloat64
+)
+
+var vffrexpBC = []float64{
+ SmallestNormalFloat64,
+ LargestSubnormalFloat64,
+ SmallestNonzeroFloat64,
+ MaxFloat64,
+ -SmallestNormalFloat64,
+ -LargestSubnormalFloat64,
+ -SmallestNonzeroFloat64,
+ -MaxFloat64,
+}
+var frexpBC = []fi{
+ {0.5, -1021},
+ {0.99999999999999978, -1022},
+ {0.5, -1073},
+ {0.99999999999999989, 1024},
+ {-0.5, -1021},
+ {-0.99999999999999978, -1022},
+ {-0.5, -1073},
+ {-0.99999999999999989, 1024},
+}
+
+var vfldexpBC = []fi{
+ {SmallestNormalFloat64, -52},
+ {LargestSubnormalFloat64, -51},
+ {SmallestNonzeroFloat64, 1074},
+ {MaxFloat64, -(1023 + 1074)},
+ {1, -1075},
+ {-1, -1075},
+ {1, 1024},
+ {-1, 1024},
+ {1.0000000000000002, -1075},
+ {1, -1075},
+}
+var ldexpBC = []float64{
+ SmallestNonzeroFloat64,
+ 1e-323, // 2**-1073
+ 1,
+ 1e-323, // 2**-1073
+ 0,
+ Copysign(0, -1),
+ Inf(1),
+ Inf(-1),
+ SmallestNonzeroFloat64,
+ 0,
+}
+
+var logbBC = []float64{
+ -1022,
+ -1023,
+ -1074,
+ 1023,
+ -1022,
+ -1023,
+ -1074,
+ 1023,
+}
+
+// Test cases were generated with Berkeley TestFloat-3e/testfloat_gen.
+// http://www.jhauser.us/arithmetic/TestFloat.html.
+// The default rounding mode is selected (nearest/even), and exception flags are ignored.
+var fmaC = []struct{ x, y, z, want float64 }{
+ // Large exponent spread
+ {-3.999999999999087, -1.1123914289620494e-16, -7.999877929687506, -7.999877929687505},
+ {-262112.0000004768, -0.06251525855623184, 1.1102230248837136e-16, 16385.99945072085},
+ {-6.462348523533467e-27, -2.3763644720331857e-211, 4.000000000931324, 4.000000000931324},
+
+ // Effective addition
+ {-2.0000000037252907, 6.7904383376e-313, -3.3951933161e-313, -1.697607001654e-312},
+ {-0.12499999999999999, 512.007568359375, -1.4193627164960366e-16, -64.00094604492188},
+ {-2.7550648847397148e-39, -3.4028301595800694e+38, 0.9960937495343386, 1.9335955376735676},
+ {5.723369164769208e+24, 3.8149300927159385e-06, 1.84489958778182e+19, 4.028324913621874e+19},
+ {-0.4843749999990904, -3.6893487872543293e+19, 9.223653786709391e+18, 2.7093936974938993e+19},
+ {-3.8146972665201165e-06, 4.2949672959999385e+09, -2.2204460489938386e-16, -16384.000003844263},
+ {6.98156394130982e-309, -1.1072962560000002e+09, -4.4414561548793455e-308, -7.73065965765153e-300},
+
+ // Effective subtraction
+ {5e-324, 4.5, -2e-323, 0},
+ {5e-324, 7, -3.5e-323, 0},
+ {5e-324, 0.5000000000000001, -5e-324, Copysign(0, -1)},
+ {-2.1240680525e-314, -1.233647078189316e+308, -0.25781249999954525, -0.25780987964919844},
+ {8.579992955364441e-308, 0.6037391876780558, -4.4501307410480706e-308, 7.29947236107098e-309},
+ {-4.450143471986689e-308, -0.9960937499927239, -4.450419332475649e-308, -1.7659233458788e-310},
+ {1.4932076393918112, -2.2248022430460833e-308, 4.449875571054211e-308, 1.127783865601762e-308},
+
+ // Overflow
+ {-2.288020632214759e+38, -8.98846570988901e+307, 1.7696041796300924e+308, Inf(0)},
+ {1.4888652783208255e+308, -9.007199254742012e+15, -6.807282911929205e+38, Inf(-1)},
+ {9.142703268902826e+192, -1.3504889569802838e+296, -1.9082200803806996e-89, Inf(-1)},
+
+ // Finite x and y, but non-finite z.
+ {31.99218749627471, -1.7976930544991702e+308, Inf(0), Inf(0)},
+ {-1.7976931281784667e+308, -2.0009765625002265, Inf(-1), Inf(-1)},
+
+ // Special
+ {0, 0, 0, 0},
+ {Copysign(0, -1), 0, 0, 0},
+ {0, 0, Copysign(0, -1), 0},
+ {Copysign(0, -1), 0, Copysign(0, -1), Copysign(0, -1)},
+ {-1.1754226043408471e-38, NaN(), Inf(0), NaN()},
+ {0, 0, 2.22507385643494e-308, 2.22507385643494e-308},
+ {-8.65697792e+09, NaN(), -7.516192799999999e+09, NaN()},
+ {-0.00012207403779029757, 3.221225471996093e+09, NaN(), NaN()},
+ {Inf(-1), 0.1252441407414153, -1.387184532981584e-76, Inf(-1)},
+ {Inf(0), 1.525878907671432e-05, -9.214364835452549e+18, Inf(0)},
+
+ // Random
+ {0.1777916152213626, -32.000015266239636, -2.2204459148334633e-16, -5.689334401293007},
+ {-2.0816681711722314e-16, -0.4997558592585846, -0.9465627129124969, -0.9465627129124968},
+ {-1.9999997615814211, 1.8518819259933516e+19, 16.874999999999996, -3.703763410463646e+19},
+ {-0.12499994039717421, 32767.99999976135, -2.0752587082923246e+19, -2.075258708292325e+19},
+ {7.705600568510257e-34, -1.801432979000528e+16, -0.17224197722973714, -0.17224197722973716},
+ {3.8988133103758913e-308, -0.9848632812499999, 3.893879244098556e-308, 5.40811742605814e-310},
+ {-0.012651981190687427, 6.911985574912436e+38, 6.669240527007144e+18, -8.745031148409496e+36},
+ {4.612811918325842e+18, 1.4901161193847641e-08, 2.6077032311277997e-08, 6.873625395187494e+10},
+ {-9.094947033611148e-13, 4.450691014249257e-308, 2.086006742350485e-308, 2.086006742346437e-308},
+ {-7.751454006381804e-05, 5.588653777189071e-308, -2.2207280111272877e-308, -2.2211612130544025e-308},
+
+ // Issue #61130
+ {-1, 1, 1, 0},
+ {1, 1, -1, 0},
+
+ // Issue #73757
+ {0x1p-1022, -0x1p-1022, 0, Copysign(0, -1)},
+ {Copysign(0, -1), 1, 0, 0},
+ {1, Copysign(0, -1), 0, 0},
+}
+
+var sqrt32 = []float32{
+ 0,
+ float32(Copysign(0, -1)),
+ float32(NaN()),
+ float32(Inf(1)),
+ float32(Inf(-1)),
+ 1,
+ 2,
+ -2,
+ 4.9790119248836735e+00,
+ 7.7388724745781045e+00,
+ -2.7688005719200159e-01,
+ -5.0106036182710749e+00,
+}
+
+func tolerance(a, b, e float64) bool {
+ // Multiplying by e here can underflow denormal values to zero.
+ // Check a==b so that at least if a and b are small and identical
+ // we say they match.
+ if a == b {
+ return true
+ }
+ d := a - b
+ if d < 0 {
+ d = -d
+ }
+
+ // note: b is correct (expected) value, a is actual value.
+ // make error tolerance a fraction of b, not a.
+ if b != 0 {
+ e = e * b
+ if e < 0 {
+ e = -e
+ }
+ }
+ return d < e
+}
+func close(a, b float64) bool { return tolerance(a, b, 1e-14) }
+func veryclose(a, b float64) bool { return tolerance(a, b, 4e-16) }
+func soclose(a, b, e float64) bool { return tolerance(a, b, e) }
+func alike(a, b float64) bool {
+ switch {
+ case IsNaN(a) && IsNaN(b):
+ return true
+ case a == b:
+ return Signbit(a) == Signbit(b)
+ }
+ return false
+}
+
+func TestNaN(t *testing.T) {
+ f64 := NaN()
+ if f64 == f64 {
+ t.Fatalf("NaN() returns %g, expected NaN", f64)
+ }
+ f32 := float32(f64)
+ if f32 == f32 {
+ t.Fatalf("float32(NaN()) is %g, expected NaN", f32)
+ }
+}
+
+func TestAcos(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ a := vf[i] / 10
+ if f := Acos(a); !close(acos[i], f) {
+ t.Errorf("Acos(%g) = %g, want %g", a, f, acos[i])
+ }
+ }
+ for i := 0; i < len(vfacosSC); i++ {
+ if f := Acos(vfacosSC[i]); !alike(acosSC[i], f) {
+ t.Errorf("Acos(%g) = %g, want %g", vfacosSC[i], f, acosSC[i])
+ }
+ }
+}
+
+func TestAcosh(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ a := 1 + Abs(vf[i])
+ if f := Acosh(a); !veryclose(acosh[i], f) {
+ t.Errorf("Acosh(%g) = %g, want %g", a, f, acosh[i])
+ }
+ }
+ for i := 0; i < len(vfacoshSC); i++ {
+ if f := Acosh(vfacoshSC[i]); !alike(acoshSC[i], f) {
+ t.Errorf("Acosh(%g) = %g, want %g", vfacoshSC[i], f, acoshSC[i])
+ }
+ }
+}
+
+func TestAsin(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ a := vf[i] / 10
+ if f := Asin(a); !veryclose(asin[i], f) {
+ t.Errorf("Asin(%g) = %g, want %g", a, f, asin[i])
+ }
+ }
+ for i := 0; i < len(vfasinSC); i++ {
+ if f := Asin(vfasinSC[i]); !alike(asinSC[i], f) {
+ t.Errorf("Asin(%g) = %g, want %g", vfasinSC[i], f, asinSC[i])
+ }
+ }
+}
+
+func TestAsinh(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Asinh(vf[i]); !veryclose(asinh[i], f) {
+ t.Errorf("Asinh(%g) = %g, want %g", vf[i], f, asinh[i])
+ }
+ }
+ for i := 0; i < len(vfasinhSC); i++ {
+ if f := Asinh(vfasinhSC[i]); !alike(asinhSC[i], f) {
+ t.Errorf("Asinh(%g) = %g, want %g", vfasinhSC[i], f, asinhSC[i])
+ }
+ }
+}
+
+func TestAtan(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Atan(vf[i]); !veryclose(atan[i], f) {
+ t.Errorf("Atan(%g) = %g, want %g", vf[i], f, atan[i])
+ }
+ }
+ for i := 0; i < len(vfatanSC); i++ {
+ if f := Atan(vfatanSC[i]); !alike(atanSC[i], f) {
+ t.Errorf("Atan(%g) = %g, want %g", vfatanSC[i], f, atanSC[i])
+ }
+ }
+}
+
+func TestAtanh(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ a := vf[i] / 10
+ if f := Atanh(a); !veryclose(atanh[i], f) {
+ t.Errorf("Atanh(%g) = %g, want %g", a, f, atanh[i])
+ }
+ }
+ for i := 0; i < len(vfatanhSC); i++ {
+ if f := Atanh(vfatanhSC[i]); !alike(atanhSC[i], f) {
+ t.Errorf("Atanh(%g) = %g, want %g", vfatanhSC[i], f, atanhSC[i])
+ }
+ }
+}
+
+func TestAtan2(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Atan2(10, vf[i]); !veryclose(atan2[i], f) {
+ t.Errorf("Atan2(10, %g) = %g, want %g", vf[i], f, atan2[i])
+ }
+ }
+ for i := 0; i < len(vfatan2SC); i++ {
+ if f := Atan2(vfatan2SC[i][0], vfatan2SC[i][1]); !alike(atan2SC[i], f) {
+ t.Errorf("Atan2(%g, %g) = %g, want %g", vfatan2SC[i][0], vfatan2SC[i][1], f, atan2SC[i])
+ }
+ }
+}
+
+func TestCbrt(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Cbrt(vf[i]); !veryclose(cbrt[i], f) {
+ t.Errorf("Cbrt(%g) = %g, want %g", vf[i], f, cbrt[i])
+ }
+ }
+ for i := 0; i < len(vfcbrtSC); i++ {
+ if f := Cbrt(vfcbrtSC[i]); !alike(cbrtSC[i], f) {
+ t.Errorf("Cbrt(%g) = %g, want %g", vfcbrtSC[i], f, cbrtSC[i])
+ }
+ }
+}
+
+func TestCeil(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Ceil(vf[i]); !alike(ceil[i], f) {
+ t.Errorf("Ceil(%g) = %g, want %g", vf[i], f, ceil[i])
+ }
+ }
+ for i := 0; i < len(vfceilSC); i++ {
+ if f := Ceil(vfceilSC[i]); !alike(ceilSC[i], f) {
+ t.Errorf("Ceil(%g) = %g, want %g", vfceilSC[i], f, ceilSC[i])
+ }
+ }
+}
+
+func TestCopysign(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Copysign(vf[i], -1); copysign[i] != f {
+ t.Errorf("Copysign(%g, -1) = %g, want %g", vf[i], f, copysign[i])
+ }
+ }
+ for i := 0; i < len(vf); i++ {
+ if f := Copysign(vf[i], 1); -copysign[i] != f {
+ t.Errorf("Copysign(%g, 1) = %g, want %g", vf[i], f, -copysign[i])
+ }
+ }
+ for i := 0; i < len(vfcopysignSC); i++ {
+ if f := Copysign(vfcopysignSC[i], -1); !alike(copysignSC[i], f) {
+ t.Errorf("Copysign(%g, -1) = %g, want %g", vfcopysignSC[i], f, copysignSC[i])
+ }
+ }
+}
+
+func TestCos(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Cos(vf[i]); !veryclose(cos[i], f) {
+ t.Errorf("Cos(%g) = %g, want %g", vf[i], f, cos[i])
+ }
+ }
+ for i := 0; i < len(vfcosSC); i++ {
+ if f := Cos(vfcosSC[i]); !alike(cosSC[i], f) {
+ t.Errorf("Cos(%g) = %g, want %g", vfcosSC[i], f, cosSC[i])
+ }
+ }
+}
+
+func TestCosh(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Cosh(vf[i]); !close(cosh[i], f) {
+ t.Errorf("Cosh(%g) = %g, want %g", vf[i], f, cosh[i])
+ }
+ }
+ for i := 0; i < len(vfcoshSC); i++ {
+ if f := Cosh(vfcoshSC[i]); !alike(coshSC[i], f) {
+ t.Errorf("Cosh(%g) = %g, want %g", vfcoshSC[i], f, coshSC[i])
+ }
+ }
+}
+
+func TestErf(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ a := vf[i] / 10
+ if f := Erf(a); !veryclose(erf[i], f) {
+ t.Errorf("Erf(%g) = %g, want %g", a, f, erf[i])
+ }
+ }
+ for i := 0; i < len(vferfSC); i++ {
+ if f := Erf(vferfSC[i]); !alike(erfSC[i], f) {
+ t.Errorf("Erf(%g) = %g, want %g", vferfSC[i], f, erfSC[i])
+ }
+ }
+}
+
+func TestErfc(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ a := vf[i] / 10
+ if f := Erfc(a); !veryclose(erfc[i], f) {
+ t.Errorf("Erfc(%g) = %g, want %g", a, f, erfc[i])
+ }
+ }
+ for i := 0; i < len(vferfcSC); i++ {
+ if f := Erfc(vferfcSC[i]); !alike(erfcSC[i], f) {
+ t.Errorf("Erfc(%g) = %g, want %g", vferfcSC[i], f, erfcSC[i])
+ }
+ }
+}
+
+func TestErfinv(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ a := vf[i] / 10
+ if f := Erfinv(a); !veryclose(erfinv[i], f) {
+ t.Errorf("Erfinv(%g) = %g, want %g", a, f, erfinv[i])
+ }
+ }
+ for i := 0; i < len(vferfinvSC); i++ {
+ if f := Erfinv(vferfinvSC[i]); !alike(erfinvSC[i], f) {
+ t.Errorf("Erfinv(%g) = %g, want %g", vferfinvSC[i], f, erfinvSC[i])
+ }
+ }
+ for x := -0.9; x <= 0.90; x += 1e-2 {
+ if f := Erf(Erfinv(x)); !close(x, f) {
+ t.Errorf("Erf(Erfinv(%g)) = %g, want %g", x, f, x)
+ }
+ }
+ for x := -0.9; x <= 0.90; x += 1e-2 {
+ if f := Erfinv(Erf(x)); !close(x, f) {
+ t.Errorf("Erfinv(Erf(%g)) = %g, want %g", x, f, x)
+ }
+ }
+}
+
+func TestErfcinv(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ a := 1.0 - (vf[i] / 10)
+ if f := Erfcinv(a); !veryclose(erfinv[i], f) {
+ t.Errorf("Erfcinv(%g) = %g, want %g", a, f, erfinv[i])
+ }
+ }
+ for i := 0; i < len(vferfcinvSC); i++ {
+ if f := Erfcinv(vferfcinvSC[i]); !alike(erfcinvSC[i], f) {
+ t.Errorf("Erfcinv(%g) = %g, want %g", vferfcinvSC[i], f, erfcinvSC[i])
+ }
+ }
+ for x := 0.1; x <= 1.9; x += 1e-2 {
+ if f := Erfc(Erfcinv(x)); !close(x, f) {
+ t.Errorf("Erfc(Erfcinv(%g)) = %g, want %g", x, f, x)
+ }
+ }
+ for x := 0.1; x <= 1.9; x += 1e-2 {
+ if f := Erfcinv(Erfc(x)); !close(x, f) {
+ t.Errorf("Erfcinv(Erfc(%g)) = %g, want %g", x, f, x)
+ }
+ }
+}
+
+func TestExp(t *testing.T) {
+ testExp(t, Exp, "Exp")
+ testExp(t, ExpGo, "ExpGo")
+}
+
+func testExp(t *testing.T, Exp func(float64) float64, name string) {
+ for i := 0; i < len(vf); i++ {
+ if f := Exp(vf[i]); !veryclose(exp[i], f) {
+ t.Errorf("%s(%g) = %g, want %g", name, vf[i], f, exp[i])
+ }
+ }
+ for i := 0; i < len(vfexpSC); i++ {
+ if f := Exp(vfexpSC[i]); !alike(expSC[i], f) {
+ t.Errorf("%s(%g) = %g, want %g", name, vfexpSC[i], f, expSC[i])
+ }
+ }
+}
+
+func TestExpm1(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ a := vf[i] / 100
+ if f := Expm1(a); !veryclose(expm1[i], f) {
+ t.Errorf("Expm1(%g) = %g, want %g", a, f, expm1[i])
+ }
+ }
+ for i := 0; i < len(vf); i++ {
+ a := vf[i] * 10
+ if f := Expm1(a); !close(expm1Large[i], f) {
+ t.Errorf("Expm1(%g) = %g, want %g", a, f, expm1Large[i])
+ }
+ }
+ for i := 0; i < len(vfexpm1SC); i++ {
+ if f := Expm1(vfexpm1SC[i]); !alike(expm1SC[i], f) {
+ t.Errorf("Expm1(%g) = %g, want %g", vfexpm1SC[i], f, expm1SC[i])
+ }
+ }
+}
+
+func TestExp2(t *testing.T) {
+ testExp2(t, Exp2, "Exp2")
+ testExp2(t, Exp2Go, "Exp2Go")
+}
+
+func testExp2(t *testing.T, Exp2 func(float64) float64, name string) {
+ for i := 0; i < len(vf); i++ {
+ if f := Exp2(vf[i]); !close(exp2[i], f) {
+ t.Errorf("%s(%g) = %g, want %g", name, vf[i], f, exp2[i])
+ }
+ }
+ for i := 0; i < len(vfexp2SC); i++ {
+ if f := Exp2(vfexp2SC[i]); !alike(exp2SC[i], f) {
+ t.Errorf("%s(%g) = %g, want %g", name, vfexp2SC[i], f, exp2SC[i])
+ }
+ }
+ for n := -1074; n < 1024; n++ {
+ f := Exp2(float64(n))
+ vf := Ldexp(1, n)
+ if f != vf {
+ t.Errorf("%s(%d) = %g, want %g", name, n, f, vf)
+ }
+ }
+}
+
+func TestAbs(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Abs(vf[i]); fabs[i] != f {
+ t.Errorf("Abs(%g) = %g, want %g", vf[i], f, fabs[i])
+ }
+ }
+ for i := 0; i < len(vffabsSC); i++ {
+ if f := Abs(vffabsSC[i]); !alike(fabsSC[i], f) {
+ t.Errorf("Abs(%g) = %g, want %g", vffabsSC[i], f, fabsSC[i])
+ }
+ }
+}
+
+func TestDim(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Dim(vf[i], 0); fdim[i] != f {
+ t.Errorf("Dim(%g, %g) = %g, want %g", vf[i], 0.0, f, fdim[i])
+ }
+ }
+ for i := 0; i < len(vffdimSC); i++ {
+ if f := Dim(vffdimSC[i][0], vffdimSC[i][1]); !alike(fdimSC[i], f) {
+ t.Errorf("Dim(%g, %g) = %g, want %g", vffdimSC[i][0], vffdimSC[i][1], f, fdimSC[i])
+ }
+ }
+ for i := 0; i < len(vffdim2SC); i++ {
+ if f := Dim(vffdim2SC[i][0], vffdim2SC[i][1]); !alike(fdimSC[i], f) {
+ t.Errorf("Dim(%g, %g) = %g, want %g", vffdim2SC[i][0], vffdim2SC[i][1], f, fdimSC[i])
+ }
+ }
+}
+
+func TestFloor(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Floor(vf[i]); !alike(floor[i], f) {
+ t.Errorf("Floor(%g) = %g, want %g", vf[i], f, floor[i])
+ }
+ }
+ for i := 0; i < len(vfceilSC); i++ {
+ if f := Floor(vfceilSC[i]); !alike(floorSC[i], f) {
+ t.Errorf("Floor(%g) = %g, want %g", vfceilSC[i], f, floorSC[i])
+ }
+ }
+}
+
+func TestMax(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Max(vf[i], ceil[i]); ceil[i] != f {
+ t.Errorf("Max(%g, %g) = %g, want %g", vf[i], ceil[i], f, ceil[i])
+ }
+ }
+ for i := 0; i < len(vffdimSC); i++ {
+ if f := Max(vffdimSC[i][0], vffdimSC[i][1]); !alike(fmaxSC[i], f) {
+ t.Errorf("Max(%g, %g) = %g, want %g", vffdimSC[i][0], vffdimSC[i][1], f, fmaxSC[i])
+ }
+ }
+ for i := 0; i < len(vffdim2SC); i++ {
+ if f := Max(vffdim2SC[i][0], vffdim2SC[i][1]); !alike(fmaxSC[i], f) {
+ t.Errorf("Max(%g, %g) = %g, want %g", vffdim2SC[i][0], vffdim2SC[i][1], f, fmaxSC[i])
+ }
+ }
+}
+
+func TestMin(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Min(vf[i], floor[i]); floor[i] != f {
+ t.Errorf("Min(%g, %g) = %g, want %g", vf[i], floor[i], f, floor[i])
+ }
+ }
+ for i := 0; i < len(vffdimSC); i++ {
+ if f := Min(vffdimSC[i][0], vffdimSC[i][1]); !alike(fminSC[i], f) {
+ t.Errorf("Min(%g, %g) = %g, want %g", vffdimSC[i][0], vffdimSC[i][1], f, fminSC[i])
+ }
+ }
+ for i := 0; i < len(vffdim2SC); i++ {
+ if f := Min(vffdim2SC[i][0], vffdim2SC[i][1]); !alike(fminSC[i], f) {
+ t.Errorf("Min(%g, %g) = %g, want %g", vffdim2SC[i][0], vffdim2SC[i][1], f, fminSC[i])
+ }
+ }
+}
+
+func TestMod(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Mod(10, vf[i]); fmod[i] != f {
+ t.Errorf("Mod(10, %g) = %g, want %g", vf[i], f, fmod[i])
+ }
+ }
+ for i := 0; i < len(vffmodSC); i++ {
+ if f := Mod(vffmodSC[i][0], vffmodSC[i][1]); !alike(fmodSC[i], f) {
+ t.Errorf("Mod(%g, %g) = %g, want %g", vffmodSC[i][0], vffmodSC[i][1], f, fmodSC[i])
+ }
+ }
+ // verify precision of result for extreme inputs
+ if f := Mod(5.9790119248836734e+200, 1.1258465975523544); 0.6447968302508578 != f {
+ t.Errorf("Remainder(5.9790119248836734e+200, 1.1258465975523544) = %g, want 0.6447968302508578", f)
+ }
+}
+
+func TestFrexp(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f, j := Frexp(vf[i]); !veryclose(frexp[i].f, f) || frexp[i].i != j {
+ t.Errorf("Frexp(%g) = %g, %d, want %g, %d", vf[i], f, j, frexp[i].f, frexp[i].i)
+ }
+ }
+ for i := 0; i < len(vffrexpSC); i++ {
+ if f, j := Frexp(vffrexpSC[i]); !alike(frexpSC[i].f, f) || frexpSC[i].i != j {
+ t.Errorf("Frexp(%g) = %g, %d, want %g, %d", vffrexpSC[i], f, j, frexpSC[i].f, frexpSC[i].i)
+ }
+ }
+ for i := 0; i < len(vffrexpBC); i++ {
+ if f, j := Frexp(vffrexpBC[i]); !alike(frexpBC[i].f, f) || frexpBC[i].i != j {
+ t.Errorf("Frexp(%g) = %g, %d, want %g, %d", vffrexpBC[i], f, j, frexpBC[i].f, frexpBC[i].i)
+ }
+ }
+}
+
+func TestGamma(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Gamma(vf[i]); !close(gamma[i], f) {
+ t.Errorf("Gamma(%g) = %g, want %g", vf[i], f, gamma[i])
+ }
+ }
+ for _, g := range vfgamma {
+ f := Gamma(g[0])
+ var ok bool
+ if IsNaN(g[1]) || IsInf(g[1], 0) || g[1] == 0 || f == 0 {
+ ok = alike(g[1], f)
+ } else if g[0] > -50 && g[0] <= 171 {
+ ok = veryclose(g[1], f)
+ } else {
+ ok = close(g[1], f)
+ }
+ if !ok {
+ t.Errorf("Gamma(%g) = %g, want %g", g[0], f, g[1])
+ }
+ }
+}
+
+func TestHypot(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ a := Abs(1e200 * tanh[i] * Sqrt(2))
+ if f := Hypot(1e200*tanh[i], 1e200*tanh[i]); !veryclose(a, f) {
+ t.Errorf("Hypot(%g, %g) = %g, want %g", 1e200*tanh[i], 1e200*tanh[i], f, a)
+ }
+ }
+ for i := 0; i < len(vfhypotSC); i++ {
+ if f := Hypot(vfhypotSC[i][0], vfhypotSC[i][1]); !alike(hypotSC[i], f) {
+ t.Errorf("Hypot(%g, %g) = %g, want %g", vfhypotSC[i][0], vfhypotSC[i][1], f, hypotSC[i])
+ }
+ }
+}
+
+func TestHypotGo(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ a := Abs(1e200 * tanh[i] * Sqrt(2))
+ if f := HypotGo(1e200*tanh[i], 1e200*tanh[i]); !veryclose(a, f) {
+ t.Errorf("HypotGo(%g, %g) = %g, want %g", 1e200*tanh[i], 1e200*tanh[i], f, a)
+ }
+ }
+ for i := 0; i < len(vfhypotSC); i++ {
+ if f := HypotGo(vfhypotSC[i][0], vfhypotSC[i][1]); !alike(hypotSC[i], f) {
+ t.Errorf("HypotGo(%g, %g) = %g, want %g", vfhypotSC[i][0], vfhypotSC[i][1], f, hypotSC[i])
+ }
+ }
+}
+
+func TestIlogb(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ a := frexp[i].i - 1 // adjust because fr in the interval [½, 1)
+ if e := Ilogb(vf[i]); a != e {
+ t.Errorf("Ilogb(%g) = %d, want %d", vf[i], e, a)
+ }
+ }
+ for i := 0; i < len(vflogbSC); i++ {
+ if e := Ilogb(vflogbSC[i]); ilogbSC[i] != e {
+ t.Errorf("Ilogb(%g) = %d, want %d", vflogbSC[i], e, ilogbSC[i])
+ }
+ }
+ for i := 0; i < len(vffrexpBC); i++ {
+ if e := Ilogb(vffrexpBC[i]); int(logbBC[i]) != e {
+ t.Errorf("Ilogb(%g) = %d, want %d", vffrexpBC[i], e, int(logbBC[i]))
+ }
+ }
+}
+
+func TestJ0(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := J0(vf[i]); !soclose(j0[i], f, 4e-14) {
+ t.Errorf("J0(%g) = %g, want %g", vf[i], f, j0[i])
+ }
+ }
+ for i := 0; i < len(vfj0SC); i++ {
+ if f := J0(vfj0SC[i]); !alike(j0SC[i], f) {
+ t.Errorf("J0(%g) = %g, want %g", vfj0SC[i], f, j0SC[i])
+ }
+ }
+}
+
+func TestJ1(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := J1(vf[i]); !close(j1[i], f) {
+ t.Errorf("J1(%g) = %g, want %g", vf[i], f, j1[i])
+ }
+ }
+ for i := 0; i < len(vfj0SC); i++ {
+ if f := J1(vfj0SC[i]); !alike(j1SC[i], f) {
+ t.Errorf("J1(%g) = %g, want %g", vfj0SC[i], f, j1SC[i])
+ }
+ }
+}
+
+func TestJn(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Jn(2, vf[i]); !close(j2[i], f) {
+ t.Errorf("Jn(2, %g) = %g, want %g", vf[i], f, j2[i])
+ }
+ if f := Jn(-3, vf[i]); !close(jM3[i], f) {
+ t.Errorf("Jn(-3, %g) = %g, want %g", vf[i], f, jM3[i])
+ }
+ }
+ for i := 0; i < len(vfj0SC); i++ {
+ if f := Jn(2, vfj0SC[i]); !alike(j2SC[i], f) {
+ t.Errorf("Jn(2, %g) = %g, want %g", vfj0SC[i], f, j2SC[i])
+ }
+ if f := Jn(-3, vfj0SC[i]); !alike(jM3SC[i], f) {
+ t.Errorf("Jn(-3, %g) = %g, want %g", vfj0SC[i], f, jM3SC[i])
+ }
+ }
+}
+
+func TestLdexp(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Ldexp(frexp[i].f, frexp[i].i); !veryclose(vf[i], f) {
+ t.Errorf("Ldexp(%g, %d) = %g, want %g", frexp[i].f, frexp[i].i, f, vf[i])
+ }
+ }
+ for i := 0; i < len(vffrexpSC); i++ {
+ if f := Ldexp(frexpSC[i].f, frexpSC[i].i); !alike(vffrexpSC[i], f) {
+ t.Errorf("Ldexp(%g, %d) = %g, want %g", frexpSC[i].f, frexpSC[i].i, f, vffrexpSC[i])
+ }
+ }
+ for i := 0; i < len(vfldexpSC); i++ {
+ if f := Ldexp(vfldexpSC[i].f, vfldexpSC[i].i); !alike(ldexpSC[i], f) {
+ t.Errorf("Ldexp(%g, %d) = %g, want %g", vfldexpSC[i].f, vfldexpSC[i].i, f, ldexpSC[i])
+ }
+ }
+ for i := 0; i < len(vffrexpBC); i++ {
+ if f := Ldexp(frexpBC[i].f, frexpBC[i].i); !alike(vffrexpBC[i], f) {
+ t.Errorf("Ldexp(%g, %d) = %g, want %g", frexpBC[i].f, frexpBC[i].i, f, vffrexpBC[i])
+ }
+ }
+ for i := 0; i < len(vfldexpBC); i++ {
+ if f := Ldexp(vfldexpBC[i].f, vfldexpBC[i].i); !alike(ldexpBC[i], f) {
+ t.Errorf("Ldexp(%g, %d) = %g, want %g", vfldexpBC[i].f, vfldexpBC[i].i, f, ldexpBC[i])
+ }
+ }
+}
+
+func TestLgamma(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f, s := Lgamma(vf[i]); !close(lgamma[i].f, f) || lgamma[i].i != s {
+ t.Errorf("Lgamma(%g) = %g, %d, want %g, %d", vf[i], f, s, lgamma[i].f, lgamma[i].i)
+ }
+ }
+ for i := 0; i < len(vflgammaSC); i++ {
+ if f, s := Lgamma(vflgammaSC[i]); !alike(lgammaSC[i].f, f) || lgammaSC[i].i != s {
+ t.Errorf("Lgamma(%g) = %g, %d, want %g, %d", vflgammaSC[i], f, s, lgammaSC[i].f, lgammaSC[i].i)
+ }
+ }
+}
+
+func TestLog(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ a := Abs(vf[i])
+ if f := Log(a); log[i] != f {
+ t.Errorf("Log(%g) = %g, want %g", a, f, log[i])
+ }
+ }
+ if f := Log(10); f != Ln10 {
+ t.Errorf("Log(%g) = %g, want %g", 10.0, f, Ln10)
+ }
+ for i := 0; i < len(vflogSC); i++ {
+ if f := Log(vflogSC[i]); !alike(logSC[i], f) {
+ t.Errorf("Log(%g) = %g, want %g", vflogSC[i], f, logSC[i])
+ }
+ }
+}
+
+func TestLogb(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Logb(vf[i]); logb[i] != f {
+ t.Errorf("Logb(%g) = %g, want %g", vf[i], f, logb[i])
+ }
+ }
+ for i := 0; i < len(vflogbSC); i++ {
+ if f := Logb(vflogbSC[i]); !alike(logbSC[i], f) {
+ t.Errorf("Logb(%g) = %g, want %g", vflogbSC[i], f, logbSC[i])
+ }
+ }
+ for i := 0; i < len(vffrexpBC); i++ {
+ if f := Logb(vffrexpBC[i]); !alike(logbBC[i], f) {
+ t.Errorf("Logb(%g) = %g, want %g", vffrexpBC[i], f, logbBC[i])
+ }
+ }
+}
+
+func TestLog10(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ a := Abs(vf[i])
+ if f := Log10(a); !veryclose(log10[i], f) {
+ t.Errorf("Log10(%g) = %g, want %g", a, f, log10[i])
+ }
+ }
+ if f := Log10(E); f != Log10E {
+ t.Errorf("Log10(%g) = %g, want %g", E, f, Log10E)
+ }
+ for i := 0; i < len(vflogSC); i++ {
+ if f := Log10(vflogSC[i]); !alike(logSC[i], f) {
+ t.Errorf("Log10(%g) = %g, want %g", vflogSC[i], f, logSC[i])
+ }
+ }
+}
+
+func TestLog1p(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ a := vf[i] / 100
+ if f := Log1p(a); !veryclose(log1p[i], f) {
+ t.Errorf("Log1p(%g) = %g, want %g", a, f, log1p[i])
+ }
+ }
+ a := 9.0
+ if f := Log1p(a); f != Ln10 {
+ t.Errorf("Log1p(%g) = %g, want %g", a, f, Ln10)
+ }
+ for i := 0; i < len(vflogSC); i++ {
+ if f := Log1p(vflog1pSC[i]); !alike(log1pSC[i], f) {
+ t.Errorf("Log1p(%g) = %g, want %g", vflog1pSC[i], f, log1pSC[i])
+ }
+ }
+}
+
+func TestLog2(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ a := Abs(vf[i])
+ if f := Log2(a); !veryclose(log2[i], f) {
+ t.Errorf("Log2(%g) = %g, want %g", a, f, log2[i])
+ }
+ }
+ if f := Log2(E); f != Log2E {
+ t.Errorf("Log2(%g) = %g, want %g", E, f, Log2E)
+ }
+ for i := 0; i < len(vflogSC); i++ {
+ if f := Log2(vflogSC[i]); !alike(logSC[i], f) {
+ t.Errorf("Log2(%g) = %g, want %g", vflogSC[i], f, logSC[i])
+ }
+ }
+ for i := -1074; i <= 1023; i++ {
+ f := Ldexp(1, i)
+ l := Log2(f)
+ if l != float64(i) {
+ t.Errorf("Log2(2**%d) = %g, want %d", i, l, i)
+ }
+ }
+}
+
+func TestModf(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f, g := Modf(vf[i]); !veryclose(modf[i][0], f) || !veryclose(modf[i][1], g) {
+ t.Errorf("Modf(%g) = %g, %g, want %g, %g", vf[i], f, g, modf[i][0], modf[i][1])
+ }
+ }
+ for i := 0; i < len(vfmodfSC); i++ {
+ if f, g := Modf(vfmodfSC[i]); !alike(modfSC[i][0], f) || !alike(modfSC[i][1], g) {
+ t.Errorf("Modf(%g) = %g, %g, want %g, %g", vfmodfSC[i], f, g, modfSC[i][0], modfSC[i][1])
+ }
+ }
+}
+
+func TestNextafter32(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ vfi := float32(vf[i])
+ if f := Nextafter32(vfi, 10); nextafter32[i] != f {
+ t.Errorf("Nextafter32(%g, %g) = %g want %g", vfi, 10.0, f, nextafter32[i])
+ }
+ }
+ for i := 0; i < len(vfnextafter32SC); i++ {
+ if f := Nextafter32(vfnextafter32SC[i][0], vfnextafter32SC[i][1]); !alike(float64(nextafter32SC[i]), float64(f)) {
+ t.Errorf("Nextafter32(%g, %g) = %g want %g", vfnextafter32SC[i][0], vfnextafter32SC[i][1], f, nextafter32SC[i])
+ }
+ }
+}
+
+func TestNextafter64(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Nextafter(vf[i], 10); nextafter64[i] != f {
+ t.Errorf("Nextafter64(%g, %g) = %g want %g", vf[i], 10.0, f, nextafter64[i])
+ }
+ }
+ for i := 0; i < len(vfnextafter64SC); i++ {
+ if f := Nextafter(vfnextafter64SC[i][0], vfnextafter64SC[i][1]); !alike(nextafter64SC[i], f) {
+ t.Errorf("Nextafter64(%g, %g) = %g want %g", vfnextafter64SC[i][0], vfnextafter64SC[i][1], f, nextafter64SC[i])
+ }
+ }
+}
+
+func TestPow(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Pow(10, vf[i]); !close(pow[i], f) {
+ t.Errorf("Pow(10, %g) = %g, want %g", vf[i], f, pow[i])
+ }
+ }
+ for i := 0; i < len(vfpowSC); i++ {
+ if f := Pow(vfpowSC[i][0], vfpowSC[i][1]); !alike(powSC[i], f) {
+ t.Errorf("Pow(%g, %g) = %g, want %g", vfpowSC[i][0], vfpowSC[i][1], f, powSC[i])
+ }
+ }
+}
+
+func TestPow10(t *testing.T) {
+ for i := 0; i < len(vfpow10SC); i++ {
+ if f := Pow10(vfpow10SC[i]); !alike(pow10SC[i], f) {
+ t.Errorf("Pow10(%d) = %g, want %g", vfpow10SC[i], f, pow10SC[i])
+ }
+ }
+}
+
+func TestRemainder(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Remainder(10, vf[i]); remainder[i] != f {
+ t.Errorf("Remainder(10, %g) = %g, want %g", vf[i], f, remainder[i])
+ }
+ }
+ for i := 0; i < len(vffmodSC); i++ {
+ if f := Remainder(vffmodSC[i][0], vffmodSC[i][1]); !alike(fmodSC[i], f) {
+ t.Errorf("Remainder(%g, %g) = %g, want %g", vffmodSC[i][0], vffmodSC[i][1], f, fmodSC[i])
+ }
+ }
+ // verify precision of result for extreme inputs
+ if f := Remainder(5.9790119248836734e+200, 1.1258465975523544); -0.4810497673014966 != f {
+ t.Errorf("Remainder(5.9790119248836734e+200, 1.1258465975523544) = %g, want -0.4810497673014966", f)
+ }
+ // verify that sign is correct when r == 0.
+ test := func(x, y float64) {
+ if r := Remainder(x, y); r == 0 && Signbit(r) != Signbit(x) {
+ t.Errorf("Remainder(x=%f, y=%f) = %f, sign of (zero) result should agree with sign of x", x, y, r)
+ }
+ }
+ for x := 0.0; x <= 3.0; x += 1 {
+ for y := 1.0; y <= 3.0; y += 1 {
+ test(x, y)
+ test(x, -y)
+ test(-x, y)
+ test(-x, -y)
+ }
+ }
+}
+
+func TestRound(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Round(vf[i]); !alike(round[i], f) {
+ t.Errorf("Round(%g) = %g, want %g", vf[i], f, round[i])
+ }
+ }
+ for i := 0; i < len(vfroundSC); i++ {
+ if f := Round(vfroundSC[i][0]); !alike(vfroundSC[i][1], f) {
+ t.Errorf("Round(%g) = %g, want %g", vfroundSC[i][0], f, vfroundSC[i][1])
+ }
+ }
+}
+
+func TestRoundToEven(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := RoundToEven(vf[i]); !alike(round[i], f) {
+ t.Errorf("RoundToEven(%g) = %g, want %g", vf[i], f, round[i])
+ }
+ }
+ for i := 0; i < len(vfroundEvenSC); i++ {
+ if f := RoundToEven(vfroundEvenSC[i][0]); !alike(vfroundEvenSC[i][1], f) {
+ t.Errorf("RoundToEven(%g) = %g, want %g", vfroundEvenSC[i][0], f, vfroundEvenSC[i][1])
+ }
+ }
+}
+
+func TestSignbit(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Signbit(vf[i]); signbit[i] != f {
+ t.Errorf("Signbit(%g) = %t, want %t", vf[i], f, signbit[i])
+ }
+ }
+ for i := 0; i < len(vfsignbitSC); i++ {
+ if f := Signbit(vfsignbitSC[i]); signbitSC[i] != f {
+ t.Errorf("Signbit(%g) = %t, want %t", vfsignbitSC[i], f, signbitSC[i])
+ }
+ }
+}
+func TestSin(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Sin(vf[i]); !veryclose(sin[i], f) {
+ t.Errorf("Sin(%g) = %g, want %g", vf[i], f, sin[i])
+ }
+ }
+ for i := 0; i < len(vfsinSC); i++ {
+ if f := Sin(vfsinSC[i]); !alike(sinSC[i], f) {
+ t.Errorf("Sin(%g) = %g, want %g", vfsinSC[i], f, sinSC[i])
+ }
+ }
+}
+
+func TestSincos(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if s, c := Sincos(vf[i]); !veryclose(sin[i], s) || !veryclose(cos[i], c) {
+ t.Errorf("Sincos(%g) = %g, %g want %g, %g", vf[i], s, c, sin[i], cos[i])
+ }
+ }
+}
+
+func TestSinh(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Sinh(vf[i]); !close(sinh[i], f) {
+ t.Errorf("Sinh(%g) = %g, want %g", vf[i], f, sinh[i])
+ }
+ }
+ for i := 0; i < len(vfsinhSC); i++ {
+ if f := Sinh(vfsinhSC[i]); !alike(sinhSC[i], f) {
+ t.Errorf("Sinh(%g) = %g, want %g", vfsinhSC[i], f, sinhSC[i])
+ }
+ }
+}
+
+func TestSqrt(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ a := Abs(vf[i])
+ if f := SqrtGo(a); sqrt[i] != f {
+ t.Errorf("SqrtGo(%g) = %g, want %g", a, f, sqrt[i])
+ }
+ a = Abs(vf[i])
+ if f := Sqrt(a); sqrt[i] != f {
+ t.Errorf("Sqrt(%g) = %g, want %g", a, f, sqrt[i])
+ }
+ }
+ for i := 0; i < len(vfsqrtSC); i++ {
+ if f := SqrtGo(vfsqrtSC[i]); !alike(sqrtSC[i], f) {
+ t.Errorf("SqrtGo(%g) = %g, want %g", vfsqrtSC[i], f, sqrtSC[i])
+ }
+ if f := Sqrt(vfsqrtSC[i]); !alike(sqrtSC[i], f) {
+ t.Errorf("Sqrt(%g) = %g, want %g", vfsqrtSC[i], f, sqrtSC[i])
+ }
+ }
+}
+
+func TestTan(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Tan(vf[i]); !veryclose(tan[i], f) {
+ t.Errorf("Tan(%g) = %g, want %g", vf[i], f, tan[i])
+ }
+ }
+ // same special cases as Sin
+ for i := 0; i < len(vfsinSC); i++ {
+ if f := Tan(vfsinSC[i]); !alike(sinSC[i], f) {
+ t.Errorf("Tan(%g) = %g, want %g", vfsinSC[i], f, sinSC[i])
+ }
+ }
+}
+
+func TestTanh(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Tanh(vf[i]); !veryclose(tanh[i], f) {
+ t.Errorf("Tanh(%g) = %g, want %g", vf[i], f, tanh[i])
+ }
+ }
+ for i := 0; i < len(vftanhSC); i++ {
+ if f := Tanh(vftanhSC[i]); !alike(tanhSC[i], f) {
+ t.Errorf("Tanh(%g) = %g, want %g", vftanhSC[i], f, tanhSC[i])
+ }
+ }
+}
+
+func TestTrunc(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ if f := Trunc(vf[i]); !alike(trunc[i], f) {
+ t.Errorf("Trunc(%g) = %g, want %g", vf[i], f, trunc[i])
+ }
+ }
+ for i := 0; i < len(vfceilSC); i++ {
+ if f := Trunc(vfceilSC[i]); !alike(truncSC[i], f) {
+ t.Errorf("Trunc(%g) = %g, want %g", vfceilSC[i], f, truncSC[i])
+ }
+ }
+}
+
+func TestY0(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ a := Abs(vf[i])
+ if f := Y0(a); !close(y0[i], f) {
+ t.Errorf("Y0(%g) = %g, want %g", a, f, y0[i])
+ }
+ }
+ for i := 0; i < len(vfy0SC); i++ {
+ if f := Y0(vfy0SC[i]); !alike(y0SC[i], f) {
+ t.Errorf("Y0(%g) = %g, want %g", vfy0SC[i], f, y0SC[i])
+ }
+ }
+}
+
+func TestY1(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ a := Abs(vf[i])
+ if f := Y1(a); !soclose(y1[i], f, 2e-14) {
+ t.Errorf("Y1(%g) = %g, want %g", a, f, y1[i])
+ }
+ }
+ for i := 0; i < len(vfy0SC); i++ {
+ if f := Y1(vfy0SC[i]); !alike(y1SC[i], f) {
+ t.Errorf("Y1(%g) = %g, want %g", vfy0SC[i], f, y1SC[i])
+ }
+ }
+}
+
+func TestYn(t *testing.T) {
+ for i := 0; i < len(vf); i++ {
+ a := Abs(vf[i])
+ if f := Yn(2, a); !close(y2[i], f) {
+ t.Errorf("Yn(2, %g) = %g, want %g", a, f, y2[i])
+ }
+ if f := Yn(-3, a); !close(yM3[i], f) {
+ t.Errorf("Yn(-3, %g) = %g, want %g", a, f, yM3[i])
+ }
+ }
+ for i := 0; i < len(vfy0SC); i++ {
+ if f := Yn(2, vfy0SC[i]); !alike(y2SC[i], f) {
+ t.Errorf("Yn(2, %g) = %g, want %g", vfy0SC[i], f, y2SC[i])
+ }
+ if f := Yn(-3, vfy0SC[i]); !alike(yM3SC[i], f) {
+ t.Errorf("Yn(-3, %g) = %g, want %g", vfy0SC[i], f, yM3SC[i])
+ }
+ }
+ if f := Yn(0, 0); !alike(Inf(-1), f) {
+ t.Errorf("Yn(0, 0) = %g, want %g", f, Inf(-1))
+ }
+}
+
+var PortableFMA = FMA // hide call from compiler intrinsic; falls back to portable code
+
+func TestFMA(t *testing.T) {
+ for _, c := range fmaC {
+ got := FMA(c.x, c.y, c.z)
+ if !alike(got, c.want) {
+ t.Errorf("FMA(%g,%g,%g) == %g; want %g", c.x, c.y, c.z, got, c.want)
+ }
+ got = PortableFMA(c.x, c.y, c.z)
+ if !alike(got, c.want) {
+ t.Errorf("PortableFMA(%g,%g,%g) == %g; want %g", c.x, c.y, c.z, got, c.want)
+ }
+ }
+}
+
+//go:noinline
+func fmsub(x, y, z float64) float64 {
+ return FMA(x, y, -z)
+}
+
+//go:noinline
+func fnmsub(x, y, z float64) float64 {
+ return FMA(-x, y, z)
+}
+
+//go:noinline
+func fnmadd(x, y, z float64) float64 {
+ return FMA(-x, y, -z)
+}
+
+func TestFMANegativeArgs(t *testing.T) {
+ // Some architectures have instructions for fused multiply-subtract and
+ // also negated variants of fused multiply-add and subtract. This test
+ // aims to check that the optimizations that generate those instructions
+ // are applied correctly, if they exist.
+ for _, c := range fmaC {
+ want := PortableFMA(c.x, c.y, -c.z)
+ got := fmsub(c.x, c.y, c.z)
+ if !alike(got, want) {
+ t.Errorf("FMA(%g, %g, -(%g)) == %g, want %g", c.x, c.y, c.z, got, want)
+ }
+ want = PortableFMA(-c.x, c.y, c.z)
+ got = fnmsub(c.x, c.y, c.z)
+ if !alike(got, want) {
+ t.Errorf("FMA(-(%g), %g, %g) == %g, want %g", c.x, c.y, c.z, got, want)
+ }
+ want = PortableFMA(-c.x, c.y, -c.z)
+ got = fnmadd(c.x, c.y, c.z)
+ if !alike(got, want) {
+ t.Errorf("FMA(-(%g), %g, -(%g)) == %g, want %g", c.x, c.y, c.z, got, want)
+ }
+ }
+}
+
+// Check that math functions of high angle values
+// return accurate results. [Since (vf[i] + large) - large != vf[i],
+// testing for Trig(vf[i] + large) == Trig(vf[i]), where large is
+// a multiple of 2*Pi, is misleading.]
+func TestLargeCos(t *testing.T) {
+ large := float64(100000 * Pi)
+ for i := 0; i < len(vf); i++ {
+ f1 := cosLarge[i]
+ f2 := Cos(vf[i] + large)
+ if !close(f1, f2) {
+ t.Errorf("Cos(%g) = %g, want %g", vf[i]+large, f2, f1)
+ }
+ }
+}
+
+func TestLargeSin(t *testing.T) {
+ large := float64(100000 * Pi)
+ for i := 0; i < len(vf); i++ {
+ f1 := sinLarge[i]
+ f2 := Sin(vf[i] + large)
+ if !close(f1, f2) {
+ t.Errorf("Sin(%g) = %g, want %g", vf[i]+large, f2, f1)
+ }
+ }
+}
+
+func TestLargeSincos(t *testing.T) {
+ large := float64(100000 * Pi)
+ for i := 0; i < len(vf); i++ {
+ f1, g1 := sinLarge[i], cosLarge[i]
+ f2, g2 := Sincos(vf[i] + large)
+ if !close(f1, f2) || !close(g1, g2) {
+ t.Errorf("Sincos(%g) = %g, %g, want %g, %g", vf[i]+large, f2, g2, f1, g1)
+ }
+ }
+}
+
+func TestLargeTan(t *testing.T) {
+ large := float64(100000 * Pi)
+ for i := 0; i < len(vf); i++ {
+ f1 := tanLarge[i]
+ f2 := Tan(vf[i] + large)
+ if !close(f1, f2) {
+ t.Errorf("Tan(%g) = %g, want %g", vf[i]+large, f2, f1)
+ }
+ }
+}
+
+// Check that trigReduce matches the standard reduction results for input values
+// below reduceThreshold.
+func TestTrigReduce(t *testing.T) {
+ inputs := make([]float64, len(vf))
+ // all of the standard inputs
+ copy(inputs, vf)
+ // all of the large inputs
+ large := float64(100000 * Pi)
+ for _, v := range vf {
+ inputs = append(inputs, v+large)
+ }
+ // Also test some special inputs, Pi and right below the reduceThreshold
+ inputs = append(inputs, Pi, Nextafter(ReduceThreshold, 0))
+ for _, x := range inputs {
+ // reduce the value to compare
+ j, z := TrigReduce(x)
+ xred := float64(j)*(Pi/4) + z
+
+ if f, fred := Sin(x), Sin(xred); !close(f, fred) {
+ t.Errorf("Sin(trigReduce(%g)) != Sin(%g), got %g, want %g", x, x, fred, f)
+ }
+ if f, fred := Cos(x), Cos(xred); !close(f, fred) {
+ t.Errorf("Cos(trigReduce(%g)) != Cos(%g), got %g, want %g", x, x, fred, f)
+ }
+ if f, fred := Tan(x), Tan(xred); !close(f, fred) {
+ t.Errorf(" Tan(trigReduce(%g)) != Tan(%g), got %g, want %g", x, x, fred, f)
+ }
+ f, g := Sincos(x)
+ fred, gred := Sincos(xred)
+ if !close(f, fred) || !close(g, gred) {
+ t.Errorf(" Sincos(trigReduce(%g)) != Sincos(%g), got %g, %g, want %g, %g", x, x, fred, gred, f, g)
+ }
+ }
+}
+
+// Check that math constants are accepted by compiler
+// and have right value (assumes strconv.ParseFloat works).
+// https://golang.org/issue/201
+
+type floatTest struct {
+ val any
+ name string
+ str string
+}
+
+var floatTests = []floatTest{
+ {float64(MaxFloat64), "MaxFloat64", "1.7976931348623157e+308"},
+ {float64(SmallestNonzeroFloat64), "SmallestNonzeroFloat64", "5e-324"},
+ {float32(MaxFloat32), "MaxFloat32", "3.4028235e+38"},
+ {float32(SmallestNonzeroFloat32), "SmallestNonzeroFloat32", "1e-45"},
+}
+
+func TestFloatMinMax(t *testing.T) {
+ for _, tt := range floatTests {
+ s := fmt.Sprint(tt.val)
+ if s != tt.str {
+ t.Errorf("Sprint(%v) = %s, want %s", tt.name, s, tt.str)
+ }
+ }
+}
+
+func TestFloatMinima(t *testing.T) {
+ if q := float32(SmallestNonzeroFloat32 / 2); q != 0 {
+ t.Errorf("float32(SmallestNonzeroFloat32 / 2) = %g, want 0", q)
+ }
+ if q := float64(SmallestNonzeroFloat64 / 2); q != 0 {
+ t.Errorf("float64(SmallestNonzeroFloat64 / 2) = %g, want 0", q)
+ }
+}
+
+var indirectSqrt = Sqrt
+
+// TestFloat32Sqrt checks the correctness of the float32 square root optimization result.
+func TestFloat32Sqrt(t *testing.T) {
+ for _, v := range sqrt32 {
+ want := float32(indirectSqrt(float64(v)))
+ got := float32(Sqrt(float64(v)))
+ if IsNaN(float64(want)) {
+ if !IsNaN(float64(got)) {
+ t.Errorf("got=%#v want=NaN, v=%#v", got, v)
+ }
+ continue
+ }
+ if got != want {
+ t.Errorf("got=%#v want=%#v, v=%#v", got, want, v)
+ }
+ }
+}
+
+// Benchmarks
+
+// Global exported variables are used to store the
+// return values of functions measured in the benchmarks.
+// Storing the results in these variables prevents the compiler
+// from completely optimizing the benchmarked functions away.
+var (
+ GlobalI int
+ GlobalB bool
+ GlobalF float64
+)
+
+func BenchmarkAcos(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Acos(.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkAcosh(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Acosh(1.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkAsin(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Asin(.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkAsinh(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Asinh(.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkAtan(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Atan(.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkAtanh(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Atanh(.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkAtan2(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Atan2(.5, 1)
+ }
+ GlobalF = x
+}
+
+func BenchmarkCbrt(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Cbrt(10)
+ }
+ GlobalF = x
+}
+
+func BenchmarkCeil(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Ceil(.5)
+ }
+ GlobalF = x
+}
+
+var copysignNeg = -1.0
+
+func BenchmarkCopysign(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Copysign(.5, copysignNeg)
+ }
+ GlobalF = x
+}
+
+func BenchmarkCos(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Cos(.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkCosh(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Cosh(2.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkErf(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Erf(.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkErfc(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Erfc(.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkErfinv(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Erfinv(.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkErfcinv(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Erfcinv(.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkExp(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Exp(.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkExpGo(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = ExpGo(.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkExpm1(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Expm1(.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkExp2(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Exp2(.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkExp2Go(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Exp2Go(.5)
+ }
+ GlobalF = x
+}
+
+var absPos = .5
+
+func BenchmarkAbs(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Abs(absPos)
+ }
+ GlobalF = x
+
+}
+
+func BenchmarkDim(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Dim(GlobalF, x)
+ }
+ GlobalF = x
+}
+
+func BenchmarkFloor(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Floor(.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkMax(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Max(10, 3)
+ }
+ GlobalF = x
+}
+
+func BenchmarkMin(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Min(10, 3)
+ }
+ GlobalF = x
+}
+
+func BenchmarkMod(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Mod(10, 3)
+ }
+ GlobalF = x
+}
+
+func BenchmarkFrexp(b *testing.B) {
+ x := 0.0
+ y := 0
+ for i := 0; i < b.N; i++ {
+ x, y = Frexp(8)
+ }
+ GlobalF = x
+ GlobalI = y
+}
+
+func BenchmarkGamma(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Gamma(2.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkHypot(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Hypot(3, 4)
+ }
+ GlobalF = x
+}
+
+func BenchmarkHypotGo(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = HypotGo(3, 4)
+ }
+ GlobalF = x
+}
+
+func BenchmarkIlogb(b *testing.B) {
+ x := 0
+ for i := 0; i < b.N; i++ {
+ x = Ilogb(.5)
+ }
+ GlobalI = x
+}
+
+func BenchmarkJ0(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = J0(2.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkJ1(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = J1(2.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkJn(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Jn(2, 2.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkLdexp(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Ldexp(.5, 2)
+ }
+ GlobalF = x
+}
+
+func BenchmarkLgamma(b *testing.B) {
+ x := 0.0
+ y := 0
+ for i := 0; i < b.N; i++ {
+ x, y = Lgamma(2.5)
+ }
+ GlobalF = x
+ GlobalI = y
+}
+
+func BenchmarkLog(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Log(.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkLogb(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Logb(.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkLog1p(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Log1p(.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkLog10(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Log10(.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkLog2(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Log2(.5)
+ }
+ GlobalF += x
+}
+
+func BenchmarkModf(b *testing.B) {
+ x := 0.0
+ y := 0.0
+ for i := 0; i < b.N; i++ {
+ x, y = Modf(1.5)
+ }
+ GlobalF += x
+ GlobalF += y
+}
+
+func BenchmarkNextafter32(b *testing.B) {
+ x := float32(0.0)
+ for i := 0; i < b.N; i++ {
+ x = Nextafter32(.5, 1)
+ }
+ GlobalF = float64(x)
+}
+
+func BenchmarkNextafter64(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Nextafter(.5, 1)
+ }
+ GlobalF = x
+}
+
+func BenchmarkPowInt(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Pow(2, 2)
+ }
+ GlobalF = x
+}
+
+func BenchmarkPowFrac(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Pow(2.5, 1.5)
+ }
+ GlobalF = x
+}
+
+var pow10pos = int(300)
+
+func BenchmarkPow10Pos(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Pow10(pow10pos)
+ }
+ GlobalF = x
+}
+
+var pow10neg = int(-300)
+
+func BenchmarkPow10Neg(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Pow10(pow10neg)
+ }
+ GlobalF = x
+}
+
+var roundNeg = float64(-2.5)
+
+func BenchmarkRound(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Round(roundNeg)
+ }
+ GlobalF = x
+}
+
+func BenchmarkRoundToEven(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = RoundToEven(roundNeg)
+ }
+ GlobalF = x
+}
+
+func BenchmarkRemainder(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Remainder(10, 3)
+ }
+ GlobalF = x
+}
+
+var signbitPos = 2.5
+
+func BenchmarkSignbit(b *testing.B) {
+ x := false
+ for i := 0; i < b.N; i++ {
+ x = Signbit(signbitPos)
+ }
+ GlobalB = x
+}
+
+func BenchmarkSin(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Sin(.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkSincos(b *testing.B) {
+ x := 0.0
+ y := 0.0
+ for i := 0; i < b.N; i++ {
+ x, y = Sincos(.5)
+ }
+ GlobalF += x
+ GlobalF += y
+}
+
+func BenchmarkSinh(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Sinh(2.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkSqrtIndirect(b *testing.B) {
+ x, y := 0.0, 10.0
+ f := Sqrt
+ for i := 0; i < b.N; i++ {
+ x += f(y)
+ }
+ GlobalF = x
+}
+
+func BenchmarkSqrtLatency(b *testing.B) {
+ x := 10.0
+ for i := 0; i < b.N; i++ {
+ x = Sqrt(x)
+ }
+ GlobalF = x
+}
+
+func BenchmarkSqrtIndirectLatency(b *testing.B) {
+ x := 10.0
+ f := Sqrt
+ for i := 0; i < b.N; i++ {
+ x = f(x)
+ }
+ GlobalF = x
+}
+
+func BenchmarkSqrtGoLatency(b *testing.B) {
+ x := 10.0
+ for i := 0; i < b.N; i++ {
+ x = SqrtGo(x)
+ }
+ GlobalF = x
+}
+
+func isPrime(i int) bool {
+ // Yes, this is a dumb way to write this code,
+ // but calling Sqrt repeatedly in this way demonstrates
+ // the benefit of using a direct SQRT instruction on systems
+ // that have one, whereas the obvious loop seems not to
+ // demonstrate such a benefit.
+ for j := 2; float64(j) <= Sqrt(float64(i)); j++ {
+ if i%j == 0 {
+ return false
+ }
+ }
+ return true
+}
+
+func BenchmarkSqrtPrime(b *testing.B) {
+ x := false
+ for i := 0; i < b.N; i++ {
+ x = isPrime(100003)
+ }
+ GlobalB = x
+}
+
+func BenchmarkTan(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Tan(.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkTanh(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Tanh(2.5)
+ }
+ GlobalF = x
+}
+func BenchmarkTrunc(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Trunc(.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkY0(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Y0(2.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkY1(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Y1(2.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkYn(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Yn(2, 2.5)
+ }
+ GlobalF = x
+}
+
+func BenchmarkFloat64bits(b *testing.B) {
+ y := uint64(0)
+ for i := 0; i < b.N; i++ {
+ y = Float64bits(roundNeg)
+ }
+ GlobalI = int(y)
+}
+
+var roundUint64 = uint64(5)
+
+func BenchmarkFloat64frombits(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = Float64frombits(roundUint64)
+ }
+ GlobalF = x
+}
+
+var roundFloat32 = float32(-2.5)
+
+func BenchmarkFloat32bits(b *testing.B) {
+ y := uint32(0)
+ for i := 0; i < b.N; i++ {
+ y = Float32bits(roundFloat32)
+ }
+ GlobalI = int(y)
+}
+
+var roundUint32 = uint32(5)
+
+func BenchmarkFloat32frombits(b *testing.B) {
+ x := float32(0.0)
+ for i := 0; i < b.N; i++ {
+ x = Float32frombits(roundUint32)
+ }
+ GlobalF = float64(x)
+}
+
+func BenchmarkFMA(b *testing.B) {
+ x := 0.0
+ for i := 0; i < b.N; i++ {
+ x = FMA(E, Pi, x)
+ }
+ GlobalF = x
+}
diff --git a/go/src/math/arith_s390x.go b/go/src/math/arith_s390x.go
new file mode 100644
index 0000000000000000000000000000000000000000..2fda82fff4e8f6111f9406933f973e1bb86c8c9b
--- /dev/null
+++ b/go/src/math/arith_s390x.go
@@ -0,0 +1,170 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+import "internal/cpu"
+
+func expTrampolineSetup(x float64) float64
+func expAsm(x float64) float64
+
+func logTrampolineSetup(x float64) float64
+func logAsm(x float64) float64
+
+// Below here all functions are grouped in stubs.go for other
+// architectures.
+
+const haveArchLog10 = true
+
+func archLog10(x float64) float64
+func log10TrampolineSetup(x float64) float64
+func log10Asm(x float64) float64
+
+const haveArchCos = true
+
+func archCos(x float64) float64
+func cosTrampolineSetup(x float64) float64
+func cosAsm(x float64) float64
+
+const haveArchCosh = true
+
+func archCosh(x float64) float64
+func coshTrampolineSetup(x float64) float64
+func coshAsm(x float64) float64
+
+const haveArchSin = true
+
+func archSin(x float64) float64
+func sinTrampolineSetup(x float64) float64
+func sinAsm(x float64) float64
+
+const haveArchSinh = true
+
+func archSinh(x float64) float64
+func sinhTrampolineSetup(x float64) float64
+func sinhAsm(x float64) float64
+
+const haveArchTanh = true
+
+func archTanh(x float64) float64
+func tanhTrampolineSetup(x float64) float64
+func tanhAsm(x float64) float64
+
+const haveArchLog1p = true
+
+func archLog1p(x float64) float64
+func log1pTrampolineSetup(x float64) float64
+func log1pAsm(x float64) float64
+
+const haveArchAtanh = true
+
+func archAtanh(x float64) float64
+func atanhTrampolineSetup(x float64) float64
+func atanhAsm(x float64) float64
+
+const haveArchAcos = true
+
+func archAcos(x float64) float64
+func acosTrampolineSetup(x float64) float64
+func acosAsm(x float64) float64
+
+const haveArchAcosh = true
+
+func archAcosh(x float64) float64
+func acoshTrampolineSetup(x float64) float64
+func acoshAsm(x float64) float64
+
+const haveArchAsin = true
+
+func archAsin(x float64) float64
+func asinTrampolineSetup(x float64) float64
+func asinAsm(x float64) float64
+
+const haveArchAsinh = true
+
+func archAsinh(x float64) float64
+func asinhTrampolineSetup(x float64) float64
+func asinhAsm(x float64) float64
+
+const haveArchErf = true
+
+func archErf(x float64) float64
+func erfTrampolineSetup(x float64) float64
+func erfAsm(x float64) float64
+
+const haveArchErfc = true
+
+func archErfc(x float64) float64
+func erfcTrampolineSetup(x float64) float64
+func erfcAsm(x float64) float64
+
+const haveArchAtan = true
+
+func archAtan(x float64) float64
+func atanTrampolineSetup(x float64) float64
+func atanAsm(x float64) float64
+
+const haveArchAtan2 = true
+
+func archAtan2(y, x float64) float64
+func atan2TrampolineSetup(x, y float64) float64
+func atan2Asm(x, y float64) float64
+
+const haveArchCbrt = true
+
+func archCbrt(x float64) float64
+func cbrtTrampolineSetup(x float64) float64
+func cbrtAsm(x float64) float64
+
+const haveArchTan = true
+
+func archTan(x float64) float64
+func tanTrampolineSetup(x float64) float64
+func tanAsm(x float64) float64
+
+const haveArchExpm1 = true
+
+func archExpm1(x float64) float64
+func expm1TrampolineSetup(x float64) float64
+func expm1Asm(x float64) float64
+
+const haveArchPow = false
+
+func archPow(x, y float64) float64
+func powTrampolineSetup(x, y float64) float64
+func powAsm(x, y float64) float64
+
+const haveArchFrexp = false
+
+func archFrexp(x float64) (float64, int) {
+ panic("not implemented")
+}
+
+const haveArchLdexp = false
+
+func archLdexp(frac float64, exp int) float64 {
+ panic("not implemented")
+}
+
+const haveArchLog2 = false
+
+func archLog2(x float64) float64 {
+ panic("not implemented")
+}
+
+const haveArchMod = false
+
+func archMod(x, y float64) float64 {
+ panic("not implemented")
+}
+
+const haveArchRemainder = false
+
+func archRemainder(x, y float64) float64 {
+ panic("not implemented")
+}
+
+// hasVX reports whether the machine has the z/Architecture
+// vector facility installed and enabled.
+var hasVX = cpu.S390X.HasVX
diff --git a/go/src/math/arith_s390x_test.go b/go/src/math/arith_s390x_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..cfbc7b7823a93c3a3ae7457607c13e1b4f5ce640
--- /dev/null
+++ b/go/src/math/arith_s390x_test.go
@@ -0,0 +1,442 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Tests whether the non vector routines are working, even when the tests are run on a
+// vector-capable machine.
+package math_test
+
+import (
+ . "math"
+ "testing"
+)
+
+func TestCosNovec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ for i := 0; i < len(vf); i++ {
+ if f := CosNoVec(vf[i]); !veryclose(cos[i], f) {
+ t.Errorf("Cos(%g) = %g, want %g", vf[i], f, cos[i])
+ }
+ }
+ for i := 0; i < len(vfcosSC); i++ {
+ if f := CosNoVec(vfcosSC[i]); !alike(cosSC[i], f) {
+ t.Errorf("Cos(%g) = %g, want %g", vfcosSC[i], f, cosSC[i])
+ }
+ }
+}
+
+func TestCoshNovec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ for i := 0; i < len(vf); i++ {
+ if f := CoshNoVec(vf[i]); !close(cosh[i], f) {
+ t.Errorf("Cosh(%g) = %g, want %g", vf[i], f, cosh[i])
+ }
+ }
+ for i := 0; i < len(vfcoshSC); i++ {
+ if f := CoshNoVec(vfcoshSC[i]); !alike(coshSC[i], f) {
+ t.Errorf("Cosh(%g) = %g, want %g", vfcoshSC[i], f, coshSC[i])
+ }
+ }
+}
+func TestSinNovec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ for i := 0; i < len(vf); i++ {
+ if f := SinNoVec(vf[i]); !veryclose(sin[i], f) {
+ t.Errorf("Sin(%g) = %g, want %g", vf[i], f, sin[i])
+ }
+ }
+ for i := 0; i < len(vfsinSC); i++ {
+ if f := SinNoVec(vfsinSC[i]); !alike(sinSC[i], f) {
+ t.Errorf("Sin(%g) = %g, want %g", vfsinSC[i], f, sinSC[i])
+ }
+ }
+}
+
+func TestSinhNovec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ for i := 0; i < len(vf); i++ {
+ if f := SinhNoVec(vf[i]); !close(sinh[i], f) {
+ t.Errorf("Sinh(%g) = %g, want %g", vf[i], f, sinh[i])
+ }
+ }
+ for i := 0; i < len(vfsinhSC); i++ {
+ if f := SinhNoVec(vfsinhSC[i]); !alike(sinhSC[i], f) {
+ t.Errorf("Sinh(%g) = %g, want %g", vfsinhSC[i], f, sinhSC[i])
+ }
+ }
+}
+
+// Check that math functions of high angle values
+// return accurate results. [Since (vf[i] + large) - large != vf[i],
+// testing for Trig(vf[i] + large) == Trig(vf[i]), where large is
+// a multiple of 2*Pi, is misleading.]
+func TestLargeCosNovec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ large := float64(100000 * Pi)
+ for i := 0; i < len(vf); i++ {
+ f1 := cosLarge[i]
+ f2 := CosNoVec(vf[i] + large)
+ if !close(f1, f2) {
+ t.Errorf("Cos(%g) = %g, want %g", vf[i]+large, f2, f1)
+ }
+ }
+}
+
+func TestLargeSinNovec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ large := float64(100000 * Pi)
+ for i := 0; i < len(vf); i++ {
+ f1 := sinLarge[i]
+ f2 := SinNoVec(vf[i] + large)
+ if !close(f1, f2) {
+ t.Errorf("Sin(%g) = %g, want %g", vf[i]+large, f2, f1)
+ }
+ }
+}
+
+func TestLargeTanNovec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ large := float64(100000 * Pi)
+ for i := 0; i < len(vf); i++ {
+ f1 := tanLarge[i]
+ f2 := TanNovec(vf[i] + large)
+ if !close(f1, f2) {
+ t.Errorf("Tan(%g) = %g, want %g", vf[i]+large, f2, f1)
+ }
+ }
+}
+
+func TestTanNovec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ for i := 0; i < len(vf); i++ {
+ if f := TanNovec(vf[i]); !veryclose(tan[i], f) {
+ t.Errorf("Tan(%g) = %g, want %g", vf[i], f, tan[i])
+ }
+ }
+ // same special cases as Sin
+ for i := 0; i < len(vfsinSC); i++ {
+ if f := TanNovec(vfsinSC[i]); !alike(sinSC[i], f) {
+ t.Errorf("Tan(%g) = %g, want %g", vfsinSC[i], f, sinSC[i])
+ }
+ }
+}
+
+func TestTanhNovec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ for i := 0; i < len(vf); i++ {
+ if f := TanhNoVec(vf[i]); !veryclose(tanh[i], f) {
+ t.Errorf("Tanh(%g) = %g, want %g", vf[i], f, tanh[i])
+ }
+ }
+ for i := 0; i < len(vftanhSC); i++ {
+ if f := TanhNoVec(vftanhSC[i]); !alike(tanhSC[i], f) {
+ t.Errorf("Tanh(%g) = %g, want %g", vftanhSC[i], f, tanhSC[i])
+ }
+ }
+
+}
+
+func TestLog10Novec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ for i := 0; i < len(vf); i++ {
+ a := Abs(vf[i])
+ if f := Log10NoVec(a); !veryclose(log10[i], f) {
+ t.Errorf("Log10(%g) = %g, want %g", a, f, log10[i])
+ }
+ }
+ if f := Log10NoVec(E); f != Log10E {
+ t.Errorf("Log10(%g) = %g, want %g", E, f, Log10E)
+ }
+ for i := 0; i < len(vflogSC); i++ {
+ if f := Log10NoVec(vflogSC[i]); !alike(logSC[i], f) {
+ t.Errorf("Log10(%g) = %g, want %g", vflogSC[i], f, logSC[i])
+ }
+ }
+}
+
+func TestLog1pNovec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ for i := 0; i < len(vf); i++ {
+ a := vf[i] / 100
+ if f := Log1pNovec(a); !veryclose(log1p[i], f) {
+ t.Errorf("Log1p(%g) = %g, want %g", a, f, log1p[i])
+ }
+ }
+ a := 9.0
+ if f := Log1pNovec(a); f != Ln10 {
+ t.Errorf("Log1p(%g) = %g, want %g", a, f, Ln10)
+ }
+ for i := 0; i < len(vflogSC); i++ {
+ if f := Log1pNovec(vflog1pSC[i]); !alike(log1pSC[i], f) {
+ t.Errorf("Log1p(%g) = %g, want %g", vflog1pSC[i], f, log1pSC[i])
+ }
+ }
+}
+
+func TestAtanhNovec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ for i := 0; i < len(vf); i++ {
+ a := vf[i] / 10
+ if f := AtanhNovec(a); !veryclose(atanh[i], f) {
+ t.Errorf("Atanh(%g) = %g, want %g", a, f, atanh[i])
+ }
+ }
+ for i := 0; i < len(vfatanhSC); i++ {
+ if f := AtanhNovec(vfatanhSC[i]); !alike(atanhSC[i], f) {
+ t.Errorf("Atanh(%g) = %g, want %g", vfatanhSC[i], f, atanhSC[i])
+ }
+ }
+}
+
+func TestAcosNovec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ for i := 0; i < len(vf); i++ {
+ a := vf[i] / 10
+ if f := AcosNovec(a); !close(acos[i], f) {
+ t.Errorf("Acos(%g) = %g, want %g", a, f, acos[i])
+ }
+ }
+ for i := 0; i < len(vfacosSC); i++ {
+ if f := AcosNovec(vfacosSC[i]); !alike(acosSC[i], f) {
+ t.Errorf("Acos(%g) = %g, want %g", vfacosSC[i], f, acosSC[i])
+ }
+ }
+}
+
+func TestAsinNovec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ for i := 0; i < len(vf); i++ {
+ a := vf[i] / 10
+ if f := AsinNovec(a); !veryclose(asin[i], f) {
+ t.Errorf("Asin(%g) = %g, want %g", a, f, asin[i])
+ }
+ }
+ for i := 0; i < len(vfasinSC); i++ {
+ if f := AsinNovec(vfasinSC[i]); !alike(asinSC[i], f) {
+ t.Errorf("Asin(%g) = %g, want %g", vfasinSC[i], f, asinSC[i])
+ }
+ }
+}
+
+func TestAcoshNovec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ for i := 0; i < len(vf); i++ {
+ a := 1 + Abs(vf[i])
+ if f := AcoshNovec(a); !veryclose(acosh[i], f) {
+ t.Errorf("Acosh(%g) = %g, want %g", a, f, acosh[i])
+ }
+ }
+ for i := 0; i < len(vfacoshSC); i++ {
+ if f := AcoshNovec(vfacoshSC[i]); !alike(acoshSC[i], f) {
+ t.Errorf("Acosh(%g) = %g, want %g", vfacoshSC[i], f, acoshSC[i])
+ }
+ }
+}
+
+func TestAsinhNovec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ for i := 0; i < len(vf); i++ {
+ if f := AsinhNovec(vf[i]); !veryclose(asinh[i], f) {
+ t.Errorf("Asinh(%g) = %g, want %g", vf[i], f, asinh[i])
+ }
+ }
+ for i := 0; i < len(vfasinhSC); i++ {
+ if f := AsinhNovec(vfasinhSC[i]); !alike(asinhSC[i], f) {
+ t.Errorf("Asinh(%g) = %g, want %g", vfasinhSC[i], f, asinhSC[i])
+ }
+ }
+}
+
+func TestErfNovec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ for i := 0; i < len(vf); i++ {
+ a := vf[i] / 10
+ if f := ErfNovec(a); !veryclose(erf[i], f) {
+ t.Errorf("Erf(%g) = %g, want %g", a, f, erf[i])
+ }
+ }
+ for i := 0; i < len(vferfSC); i++ {
+ if f := ErfNovec(vferfSC[i]); !alike(erfSC[i], f) {
+ t.Errorf("Erf(%g) = %g, want %g", vferfSC[i], f, erfSC[i])
+ }
+ }
+}
+
+func TestErfcNovec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ for i := 0; i < len(vf); i++ {
+ a := vf[i] / 10
+ if f := ErfcNovec(a); !veryclose(erfc[i], f) {
+ t.Errorf("Erfc(%g) = %g, want %g", a, f, erfc[i])
+ }
+ }
+ for i := 0; i < len(vferfcSC); i++ {
+ if f := ErfcNovec(vferfcSC[i]); !alike(erfcSC[i], f) {
+ t.Errorf("Erfc(%g) = %g, want %g", vferfcSC[i], f, erfcSC[i])
+ }
+ }
+}
+
+func TestAtanNovec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ for i := 0; i < len(vf); i++ {
+ if f := AtanNovec(vf[i]); !veryclose(atan[i], f) {
+ t.Errorf("Atan(%g) = %g, want %g", vf[i], f, atan[i])
+ }
+ }
+ for i := 0; i < len(vfatanSC); i++ {
+ if f := AtanNovec(vfatanSC[i]); !alike(atanSC[i], f) {
+ t.Errorf("Atan(%g) = %g, want %g", vfatanSC[i], f, atanSC[i])
+ }
+ }
+}
+
+func TestAtan2Novec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ for i := 0; i < len(vf); i++ {
+ if f := Atan2Novec(10, vf[i]); !veryclose(atan2[i], f) {
+ t.Errorf("Atan2(10, %g) = %g, want %g", vf[i], f, atan2[i])
+ }
+ }
+ for i := 0; i < len(vfatan2SC); i++ {
+ if f := Atan2Novec(vfatan2SC[i][0], vfatan2SC[i][1]); !alike(atan2SC[i], f) {
+ t.Errorf("Atan2(%g, %g) = %g, want %g", vfatan2SC[i][0], vfatan2SC[i][1], f, atan2SC[i])
+ }
+ }
+}
+
+func TestCbrtNovec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ for i := 0; i < len(vf); i++ {
+ if f := CbrtNovec(vf[i]); !veryclose(cbrt[i], f) {
+ t.Errorf("Cbrt(%g) = %g, want %g", vf[i], f, cbrt[i])
+ }
+ }
+ for i := 0; i < len(vfcbrtSC); i++ {
+ if f := CbrtNovec(vfcbrtSC[i]); !alike(cbrtSC[i], f) {
+ t.Errorf("Cbrt(%g) = %g, want %g", vfcbrtSC[i], f, cbrtSC[i])
+ }
+ }
+}
+
+func TestLogNovec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ for i := 0; i < len(vf); i++ {
+ a := Abs(vf[i])
+ if f := LogNovec(a); log[i] != f {
+ t.Errorf("Log(%g) = %g, want %g", a, f, log[i])
+ }
+ }
+ if f := LogNovec(10); f != Ln10 {
+ t.Errorf("Log(%g) = %g, want %g", 10.0, f, Ln10)
+ }
+ for i := 0; i < len(vflogSC); i++ {
+ if f := LogNovec(vflogSC[i]); !alike(logSC[i], f) {
+ t.Errorf("Log(%g) = %g, want %g", vflogSC[i], f, logSC[i])
+ }
+ }
+}
+
+func TestExpNovec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ testExpNovec(t, Exp, "Exp")
+ testExpNovec(t, ExpGo, "ExpGo")
+}
+
+func testExpNovec(t *testing.T, Exp func(float64) float64, name string) {
+ for i := 0; i < len(vf); i++ {
+ if f := ExpNovec(vf[i]); !veryclose(exp[i], f) {
+ t.Errorf("%s(%g) = %g, want %g", name, vf[i], f, exp[i])
+ }
+ }
+ for i := 0; i < len(vfexpSC); i++ {
+ if f := ExpNovec(vfexpSC[i]); !alike(expSC[i], f) {
+ t.Errorf("%s(%g) = %g, want %g", name, vfexpSC[i], f, expSC[i])
+ }
+ }
+}
+
+func TestExpm1Novec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ for i := 0; i < len(vf); i++ {
+ a := vf[i] / 100
+ if f := Expm1Novec(a); !veryclose(expm1[i], f) {
+ t.Errorf("Expm1(%g) = %g, want %g", a, f, expm1[i])
+ }
+ }
+ for i := 0; i < len(vf); i++ {
+ a := vf[i] * 10
+ if f := Expm1Novec(a); !close(expm1Large[i], f) {
+ t.Errorf("Expm1(%g) = %g, want %g", a, f, expm1Large[i])
+ }
+ }
+ for i := 0; i < len(vfexpm1SC); i++ {
+ if f := Expm1Novec(vfexpm1SC[i]); !alike(expm1SC[i], f) {
+ t.Errorf("Expm1(%g) = %g, want %g", vfexpm1SC[i], f, expm1SC[i])
+ }
+ }
+}
+
+func TestPowNovec(t *testing.T) {
+ if !HasVX {
+ t.Skipf("no vector support")
+ }
+ for i := 0; i < len(vf); i++ {
+ if f := PowNovec(10, vf[i]); !close(pow[i], f) {
+ t.Errorf("Pow(10, %g) = %g, want %g", vf[i], f, pow[i])
+ }
+ }
+ for i := 0; i < len(vfpowSC); i++ {
+ if f := PowNovec(vfpowSC[i][0], vfpowSC[i][1]); !alike(powSC[i], f) {
+ t.Errorf("Pow(%g, %g) = %g, want %g", vfpowSC[i][0], vfpowSC[i][1], f, powSC[i])
+ }
+ }
+}
diff --git a/go/src/math/asin.go b/go/src/math/asin.go
new file mode 100644
index 0000000000000000000000000000000000000000..8e1b2ab4916ed13202df297981a0346b6a51277a
--- /dev/null
+++ b/go/src/math/asin.go
@@ -0,0 +1,67 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+ Floating-point arcsine and arccosine.
+
+ They are implemented by computing the arctangent
+ after appropriate range reduction.
+*/
+
+// Asin returns the arcsine, in radians, of x.
+//
+// Special cases are:
+//
+// Asin(±0) = ±0
+// Asin(x) = NaN if x < -1 or x > 1
+func Asin(x float64) float64 {
+ if haveArchAsin {
+ return archAsin(x)
+ }
+ return asin(x)
+}
+
+func asin(x float64) float64 {
+ if x == 0 {
+ return x // special case
+ }
+ sign := false
+ if x < 0 {
+ x = -x
+ sign = true
+ }
+ if x > 1 {
+ return NaN() // special case
+ }
+
+ temp := Sqrt(1 - x*x)
+ if x > 0.7 {
+ temp = Pi/2 - satan(temp/x)
+ } else {
+ temp = satan(x / temp)
+ }
+
+ if sign {
+ temp = -temp
+ }
+ return temp
+}
+
+// Acos returns the arccosine, in radians, of x.
+//
+// Special case is:
+//
+// Acos(x) = NaN if x < -1 or x > 1
+func Acos(x float64) float64 {
+ if haveArchAcos {
+ return archAcos(x)
+ }
+ return acos(x)
+}
+
+func acos(x float64) float64 {
+ return Pi/2 - Asin(x)
+}
diff --git a/go/src/math/asin_s390x.s b/go/src/math/asin_s390x.s
new file mode 100644
index 0000000000000000000000000000000000000000..e5887c9bea3336a1f1695c222377a9aa290248f4
--- /dev/null
+++ b/go/src/math/asin_s390x.s
@@ -0,0 +1,162 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// Minimax polynomial coefficients and other constants
+DATA ·asinrodataL15<> + 0(SB)/8, $-1.309611320495605469
+DATA ·asinrodataL15<> + 8(SB)/8, $0x3ff921fb54442d18
+DATA ·asinrodataL15<> + 16(SB)/8, $0xbff921fb54442d18
+DATA ·asinrodataL15<> + 24(SB)/8, $1.309611320495605469
+DATA ·asinrodataL15<> + 32(SB)/8, $-0.0
+DATA ·asinrodataL15<> + 40(SB)/8, $1.199437040755305217
+DATA ·asinrodataL15<> + 48(SB)/8, $0.166666666666651626E+00
+DATA ·asinrodataL15<> + 56(SB)/8, $0.750000000042621169E-01
+DATA ·asinrodataL15<> + 64(SB)/8, $0.446428567178116477E-01
+DATA ·asinrodataL15<> + 72(SB)/8, $0.303819660378071894E-01
+DATA ·asinrodataL15<> + 80(SB)/8, $0.223715011892010405E-01
+DATA ·asinrodataL15<> + 88(SB)/8, $0.173659424522364952E-01
+DATA ·asinrodataL15<> + 96(SB)/8, $0.137810186504372266E-01
+DATA ·asinrodataL15<> + 104(SB)/8, $0.134066870961173521E-01
+DATA ·asinrodataL15<> + 112(SB)/8, $-.412335502831898721E-02
+DATA ·asinrodataL15<> + 120(SB)/8, $0.867383739532082719E-01
+DATA ·asinrodataL15<> + 128(SB)/8, $-.328765950607171649E+00
+DATA ·asinrodataL15<> + 136(SB)/8, $0.110401073869414626E+01
+DATA ·asinrodataL15<> + 144(SB)/8, $-.270694366992537307E+01
+DATA ·asinrodataL15<> + 152(SB)/8, $0.500196500770928669E+01
+DATA ·asinrodataL15<> + 160(SB)/8, $-.665866959108585165E+01
+DATA ·asinrodataL15<> + 168(SB)/8, $-.344895269334086578E+01
+DATA ·asinrodataL15<> + 176(SB)/8, $0.927437952918301659E+00
+DATA ·asinrodataL15<> + 184(SB)/8, $0.610487478874645653E+01
+DATA ·asinrodataL15<> + 192(SB)/8, $0x7ff8000000000000 //+Inf
+DATA ·asinrodataL15<> + 200(SB)/8, $-1.0
+DATA ·asinrodataL15<> + 208(SB)/8, $1.0
+DATA ·asinrodataL15<> + 216(SB)/8, $1.00000000000000000e-20
+GLOBL ·asinrodataL15<> + 0(SB), RODATA, $224
+
+// Asin returns the arcsine, in radians, of the argument.
+//
+// Special cases are:
+// Asin(±0) = ±0=
+// Asin(x) = NaN if x < -1 or x > 1
+// The algorithm used is minimax polynomial approximation
+// with coefficients determined with a Remez exchange algorithm.
+
+TEXT ·asinAsm(SB), NOSPLIT, $0-16
+ FMOVD x+0(FP), F0
+ MOVD $·asinrodataL15<>+0(SB), R9
+ LGDR F0, R7
+ FMOVD F0, F8
+ SRAD $32, R7
+ WORD $0xC0193FE6 //iilf %r1,1072079005
+ BYTE $0xA0
+ BYTE $0x9D
+ WORD $0xB91700C7 //llgtr %r12,%r7
+ MOVW R12, R8
+ MOVW R1, R6
+ CMPBGT R8, R6, L2
+ WORD $0xC0193BFF //iilf %r1,1006632959
+ BYTE $0xFF
+ BYTE $0xFF
+ MOVW R1, R6
+ CMPBGT R8, R6, L13
+L3:
+ FMOVD 216(R9), F0
+ FMADD F0, F8, F8
+L1:
+ FMOVD F8, ret+8(FP)
+ RET
+L2:
+ WORD $0xC0193FEF //iilf %r1,1072693247
+ BYTE $0xFF
+ BYTE $0xFF
+ CMPW R12, R1
+ BLE L14
+L5:
+ WORD $0xED0090D0 //cdb %f0,.L17-.L15(%r9)
+ BYTE $0x00
+ BYTE $0x19
+ BEQ L9
+ WORD $0xED0090C8 //cdb %f0,.L18-.L15(%r9)
+ BYTE $0x00
+ BYTE $0x19
+ BEQ L10
+ WFCEDBS V8, V8, V0
+ BVS L1
+ FMOVD 192(R9), F8
+ BR L1
+L13:
+ WFMDB V0, V0, V10
+L4:
+ WFMDB V10, V10, V0
+ FMOVD 184(R9), F6
+ FMOVD 176(R9), F2
+ FMOVD 168(R9), F4
+ WFMADB V0, V2, V6, V2
+ FMOVD 160(R9), F6
+ WFMADB V0, V4, V6, V4
+ FMOVD 152(R9), F6
+ WFMADB V0, V2, V6, V2
+ FMOVD 144(R9), F6
+ WFMADB V0, V4, V6, V4
+ FMOVD 136(R9), F6
+ WFMADB V0, V2, V6, V2
+ WORD $0xC0193FE6 //iilf %r1,1072079005
+ BYTE $0xA0
+ BYTE $0x9D
+ FMOVD 128(R9), F6
+ WFMADB V0, V4, V6, V4
+ FMOVD 120(R9), F6
+ WFMADB V0, V2, V6, V2
+ FMOVD 112(R9), F6
+ WFMADB V0, V4, V6, V4
+ FMOVD 104(R9), F6
+ WFMADB V0, V2, V6, V2
+ FMOVD 96(R9), F6
+ WFMADB V0, V4, V6, V4
+ FMOVD 88(R9), F6
+ WFMADB V0, V2, V6, V2
+ FMOVD 80(R9), F6
+ WFMADB V0, V4, V6, V4
+ FMOVD 72(R9), F6
+ WFMADB V0, V2, V6, V2
+ FMOVD 64(R9), F6
+ WFMADB V0, V4, V6, V4
+ FMOVD 56(R9), F6
+ WFMADB V0, V2, V6, V2
+ FMOVD 48(R9), F6
+ WFMADB V0, V4, V6, V0
+ WFMDB V8, V10, V4
+ FMADD F2, F10, F0
+ FMADD F0, F4, F8
+ CMPW R12, R1
+ BLE L1
+ FMOVD 40(R9), F0
+ FMADD F0, F1, F8
+ FMOVD F8, ret+8(FP)
+ RET
+L14:
+ FMOVD 200(R9), F0
+ FMADD F8, F8, F0
+ LCDBR F0, F10
+ WORD $0xED009020 //cdb %f0,.L39-.L15(%r9)
+ BYTE $0x00
+ BYTE $0x19
+ FSQRT F10, F8
+L6:
+ MOVW R7, R6
+ CMPBLE R6, $0, L8
+ LCDBR F8, F8
+ FMOVD 24(R9), F1
+ BR L4
+L10:
+ FMOVD 16(R9), F8
+ BR L1
+L9:
+ FMOVD 8(R9), F8
+ FMOVD F8, ret+8(FP)
+ RET
+L8:
+ FMOVD 0(R9), F1
+ BR L4
diff --git a/go/src/math/asinh.go b/go/src/math/asinh.go
new file mode 100644
index 0000000000000000000000000000000000000000..d913239d1e2c681f34005f527e301a5bcdbbe8e4
--- /dev/null
+++ b/go/src/math/asinh.go
@@ -0,0 +1,77 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// The original C code, the long comment, and the constants
+// below are from FreeBSD's /usr/src/lib/msun/src/s_asinh.c
+// and came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+//
+// asinh(x)
+// Method :
+// Based on
+// asinh(x) = sign(x) * log [ |x| + sqrt(x*x+1) ]
+// we have
+// asinh(x) := x if 1+x*x=1,
+// := sign(x)*(log(x)+ln2) for large |x|, else
+// := sign(x)*log(2|x|+1/(|x|+sqrt(x*x+1))) if|x|>2, else
+// := sign(x)*log1p(|x| + x**2/(1 + sqrt(1+x**2)))
+//
+
+// Asinh returns the inverse hyperbolic sine of x.
+//
+// Special cases are:
+//
+// Asinh(±0) = ±0
+// Asinh(±Inf) = ±Inf
+// Asinh(NaN) = NaN
+func Asinh(x float64) float64 {
+ if haveArchAsinh {
+ return archAsinh(x)
+ }
+ return asinh(x)
+}
+
+func asinh(x float64) float64 {
+ const (
+ Ln2 = 6.93147180559945286227e-01 // 0x3FE62E42FEFA39EF
+ NearZero = 1.0 / (1 << 28) // 2**-28
+ Large = 1 << 28 // 2**28
+ )
+ // special cases
+ if IsNaN(x) || IsInf(x, 0) {
+ return x
+ }
+ sign := false
+ if x < 0 {
+ x = -x
+ sign = true
+ }
+ var temp float64
+ switch {
+ case x > Large:
+ temp = Log(x) + Ln2 // |x| > 2**28
+ case x > 2:
+ temp = Log(2*x + 1/(Sqrt(x*x+1)+x)) // 2**28 > |x| > 2.0
+ case x < NearZero:
+ temp = x // |x| < 2**-28
+ default:
+ temp = Log1p(x + x*x/(1+Sqrt(1+x*x))) // 2.0 > |x| > 2**-28
+ }
+ if sign {
+ temp = -temp
+ }
+ return temp
+}
diff --git a/go/src/math/asinh_s390x.s b/go/src/math/asinh_s390x.s
new file mode 100644
index 0000000000000000000000000000000000000000..94081d3b15ce0517793cb1ec97cb8db9db98bad5
--- /dev/null
+++ b/go/src/math/asinh_s390x.s
@@ -0,0 +1,213 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// Minimax polynomial coefficients and other constants
+DATA ·asinhrodataL18<> + 0(SB)/8, $0.749999999977387502E-01
+DATA ·asinhrodataL18<> + 8(SB)/8, $-.166666666666657082E+00
+DATA ·asinhrodataL18<> + 16(SB)/8, $0.303819368237360639E-01
+DATA ·asinhrodataL18<> + 24(SB)/8, $-.446428569571752982E-01
+DATA ·asinhrodataL18<> + 32(SB)/8, $0.173500047922695924E-01
+DATA ·asinhrodataL18<> + 40(SB)/8, $-.223719767210027185E-01
+DATA ·asinhrodataL18<> + 48(SB)/8, $0.113655037946822130E-01
+DATA ·asinhrodataL18<> + 56(SB)/8, $0.579747490622448943E-02
+DATA ·asinhrodataL18<> + 64(SB)/8, $-.139372433914359122E-01
+DATA ·asinhrodataL18<> + 72(SB)/8, $-.218674325255800840E-02
+DATA ·asinhrodataL18<> + 80(SB)/8, $-.891074277756961157E-02
+DATA ·asinhrodataL18<> + 88(SB)/8, $.41375273347623353626
+DATA ·asinhrodataL18<> + 96(SB)/8, $.51487302528619766235E+04
+DATA ·asinhrodataL18<> + 104(SB)/8, $-1.67526912689208984375
+DATA ·asinhrodataL18<> + 112(SB)/8, $0.181818181818181826E+00
+DATA ·asinhrodataL18<> + 120(SB)/8, $-.165289256198351540E-01
+DATA ·asinhrodataL18<> + 128(SB)/8, $0.200350613573012186E-02
+DATA ·asinhrodataL18<> + 136(SB)/8, $-.273205381970859341E-03
+DATA ·asinhrodataL18<> + 144(SB)/8, $0.397389654305194527E-04
+DATA ·asinhrodataL18<> + 152(SB)/8, $0.938370938292558173E-06
+DATA ·asinhrodataL18<> + 160(SB)/8, $0.212881813645679599E-07
+DATA ·asinhrodataL18<> + 168(SB)/8, $-.602107458843052029E-05
+DATA ·asinhrodataL18<> + 176(SB)/8, $-.148682720127920854E-06
+DATA ·asinhrodataL18<> + 184(SB)/8, $-5.5
+DATA ·asinhrodataL18<> + 192(SB)/8, $1.0
+DATA ·asinhrodataL18<> + 200(SB)/8, $1.0E-20
+GLOBL ·asinhrodataL18<> + 0(SB), RODATA, $208
+
+// Table of log correction terms
+DATA ·asinhtab2080<> + 0(SB)/8, $0.585235384085551248E-01
+DATA ·asinhtab2080<> + 8(SB)/8, $0.412206153771168640E-01
+DATA ·asinhtab2080<> + 16(SB)/8, $0.273839003221648339E-01
+DATA ·asinhtab2080<> + 24(SB)/8, $0.166383778368856480E-01
+DATA ·asinhtab2080<> + 32(SB)/8, $0.866678223433169637E-02
+DATA ·asinhtab2080<> + 40(SB)/8, $0.319831684989627514E-02
+DATA ·asinhtab2080<> + 48(SB)/8, $0.0
+DATA ·asinhtab2080<> + 56(SB)/8, $-.113006378583725549E-02
+DATA ·asinhtab2080<> + 64(SB)/8, $-.367979419636602491E-03
+DATA ·asinhtab2080<> + 72(SB)/8, $0.213172484510484979E-02
+DATA ·asinhtab2080<> + 80(SB)/8, $0.623271047682013536E-02
+DATA ·asinhtab2080<> + 88(SB)/8, $0.118140812789696885E-01
+DATA ·asinhtab2080<> + 96(SB)/8, $0.187681358930914206E-01
+DATA ·asinhtab2080<> + 104(SB)/8, $0.269985148668178992E-01
+DATA ·asinhtab2080<> + 112(SB)/8, $0.364186619761331328E-01
+DATA ·asinhtab2080<> + 120(SB)/8, $0.469505379381388441E-01
+GLOBL ·asinhtab2080<> + 0(SB), RODATA, $128
+
+// Asinh returns the inverse hyperbolic sine of the argument.
+//
+// Special cases are:
+// Asinh(±0) = ±0
+// Asinh(±Inf) = ±Inf
+// Asinh(NaN) = NaN
+// The algorithm used is minimax polynomial approximation
+// with coefficients determined with a Remez exchange algorithm.
+
+TEXT ·asinhAsm(SB), NOSPLIT, $0-16
+ FMOVD x+0(FP), F0
+ MOVD $·asinhrodataL18<>+0(SB), R9
+ LGDR F0, R12
+ WORD $0xC0293FDF //iilf %r2,1071644671
+ BYTE $0xFF
+ BYTE $0xFF
+ SRAD $32, R12
+ WORD $0xB917001C //llgtr %r1,%r12
+ MOVW R1, R6
+ MOVW R2, R7
+ CMPBLE R6, R7, L2
+ WORD $0xC0295FEF //iilf %r2,1609564159
+ BYTE $0xFF
+ BYTE $0xFF
+ MOVW R2, R7
+ CMPBLE R6, R7, L14
+L3:
+ WORD $0xC0297FEF //iilf %r2,2146435071
+ BYTE $0xFF
+ BYTE $0xFF
+ CMPW R1, R2
+ BGT L1
+ LTDBR F0, F0
+ FMOVD F0, F10
+ BLTU L15
+L9:
+ FMOVD $0, F0
+ WFADB V0, V10, V0
+ WORD $0xC0398006 //iilf %r3,2147909631
+ BYTE $0x7F
+ BYTE $0xFF
+ LGDR F0, R5
+ SRAD $32, R5
+ MOVH $0x0, R2
+ SUBW R5, R3
+ FMOVD $0, F8
+ RISBGZ $32, $47, $0, R3, R4
+ BYTE $0x18 //lr %r1,%r4
+ BYTE $0x14
+ RISBGN $0, $31, $32, R4, R2
+ SUBW $0x100000, R1
+ SRAW $8, R1, R1
+ ORW $0x45000000, R1
+ BR L6
+L2:
+ MOVD $0x30000000, R2
+ CMPW R1, R2
+ BGT L16
+ FMOVD 200(R9), F2
+ FMADD F2, F0, F0
+L1:
+ FMOVD F0, ret+8(FP)
+ RET
+L14:
+ LTDBR F0, F0
+ BLTU L17
+ FMOVD F0, F10
+L4:
+ FMOVD 192(R9), F2
+ WFMADB V0, V0, V2, V0
+ LTDBR F0, F0
+ FSQRT F0, F8
+L5:
+ WFADB V8, V10, V0
+ WORD $0xC0398006 //iilf %r3,2147909631
+ BYTE $0x7F
+ BYTE $0xFF
+ LGDR F0, R5
+ SRAD $32, R5
+ MOVH $0x0, R2
+ SUBW R5, R3
+ RISBGZ $32, $47, $0, R3, R4
+ SRAW $8, R4, R1
+ RISBGN $0, $31, $32, R4, R2
+ ORW $0x45000000, R1
+L6:
+ LDGR R2, F2
+ FMOVD 184(R9), F0
+ WFMADB V8, V2, V0, V8
+ FMOVD 176(R9), F4
+ WFMADB V10, V2, V8, V2
+ FMOVD 168(R9), F0
+ FMOVD 160(R9), F6
+ FMOVD 152(R9), F1
+ WFMADB V2, V6, V4, V6
+ WFMADB V2, V1, V0, V1
+ WFMDB V2, V2, V4
+ FMOVD 144(R9), F0
+ WFMADB V6, V4, V1, V6
+ FMOVD 136(R9), F1
+ RISBGZ $57, $60, $51, R3, R3
+ WFMADB V2, V0, V1, V0
+ FMOVD 128(R9), F1
+ WFMADB V4, V6, V0, V6
+ FMOVD 120(R9), F0
+ WFMADB V2, V1, V0, V1
+ VLVGF $0, R1, V0
+ WFMADB V4, V6, V1, V4
+ LDEBR F0, F0
+ FMOVD 112(R9), F6
+ WFMADB V2, V4, V6, V4
+ MOVD $·asinhtab2080<>+0(SB), R1
+ FMOVD 104(R9), F1
+ WORD $0x68331000 //ld %f3,0(%r3,%r1)
+ FMOVD 96(R9), F6
+ WFMADB V2, V4, V3, V2
+ WFMADB V0, V1, V6, V0
+ FMOVD 88(R9), F4
+ WFMADB V0, V4, V2, V0
+ MOVD R12, R6
+ CMPBGT R6, $0, L1
+
+ LCDBR F0, F0
+ FMOVD F0, ret+8(FP)
+ RET
+L16:
+ WFMDB V0, V0, V1
+ FMOVD 80(R9), F6
+ WFMDB V1, V1, V4
+ FMOVD 72(R9), F2
+ WFMADB V4, V2, V6, V2
+ FMOVD 64(R9), F3
+ FMOVD 56(R9), F6
+ WFMADB V4, V2, V3, V2
+ FMOVD 48(R9), F3
+ WFMADB V4, V6, V3, V6
+ FMOVD 40(R9), F5
+ FMOVD 32(R9), F3
+ WFMADB V4, V2, V5, V2
+ WFMADB V4, V6, V3, V6
+ FMOVD 24(R9), F5
+ FMOVD 16(R9), F3
+ WFMADB V4, V2, V5, V2
+ WFMADB V4, V6, V3, V6
+ FMOVD 8(R9), F5
+ FMOVD 0(R9), F3
+ WFMADB V4, V2, V5, V2
+ WFMADB V4, V6, V3, V4
+ WFMDB V0, V1, V6
+ WFMADB V1, V4, V2, V4
+ FMADD F4, F6, F0
+ FMOVD F0, ret+8(FP)
+ RET
+L17:
+ LCDBR F0, F10
+ BR L4
+L15:
+ LCDBR F0, F10
+ BR L9
diff --git a/go/src/math/atan.go b/go/src/math/atan.go
new file mode 100644
index 0000000000000000000000000000000000000000..e722e99757fd2048f4d80fc6941b2c93f0b81442
--- /dev/null
+++ b/go/src/math/atan.go
@@ -0,0 +1,111 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+ Floating-point arctangent.
+*/
+
+// The original C code, the long comment, and the constants below were
+// from http://netlib.sandia.gov/cephes/cmath/atan.c, available from
+// http://www.netlib.org/cephes/cmath.tgz.
+// The go code is a version of the original C.
+//
+// atan.c
+// Inverse circular tangent (arctangent)
+//
+// SYNOPSIS:
+// double x, y, atan();
+// y = atan( x );
+//
+// DESCRIPTION:
+// Returns radian angle between -pi/2 and +pi/2 whose tangent is x.
+//
+// Range reduction is from three intervals into the interval from zero to 0.66.
+// The approximant uses a rational function of degree 4/5 of the form
+// x + x**3 P(x)/Q(x).
+//
+// ACCURACY:
+// Relative error:
+// arithmetic domain # trials peak rms
+// DEC -10, 10 50000 2.4e-17 8.3e-18
+// IEEE -10, 10 10^6 1.8e-16 5.0e-17
+//
+// Cephes Math Library Release 2.8: June, 2000
+// Copyright 1984, 1987, 1989, 1992, 2000 by Stephen L. Moshier
+//
+// The readme file at http://netlib.sandia.gov/cephes/ says:
+// Some software in this archive may be from the book _Methods and
+// Programs for Mathematical Functions_ (Prentice-Hall or Simon & Schuster
+// International, 1989) or from the Cephes Mathematical Library, a
+// commercial product. In either event, it is copyrighted by the author.
+// What you see here may be used freely but it comes with no support or
+// guarantee.
+//
+// The two known misprints in the book are repaired here in the
+// source listings for the gamma function and the incomplete beta
+// integral.
+//
+// Stephen L. Moshier
+// moshier@na-net.ornl.gov
+
+// xatan evaluates a series valid in the range [0, 0.66].
+func xatan(x float64) float64 {
+ const (
+ P0 = -8.750608600031904122785e-01
+ P1 = -1.615753718733365076637e+01
+ P2 = -7.500855792314704667340e+01
+ P3 = -1.228866684490136173410e+02
+ P4 = -6.485021904942025371773e+01
+ Q0 = +2.485846490142306297962e+01
+ Q1 = +1.650270098316988542046e+02
+ Q2 = +4.328810604912902668951e+02
+ Q3 = +4.853903996359136964868e+02
+ Q4 = +1.945506571482613964425e+02
+ )
+ z := x * x
+ z = z * ((((P0*z+P1)*z+P2)*z+P3)*z + P4) / (((((z+Q0)*z+Q1)*z+Q2)*z+Q3)*z + Q4)
+ z = x*z + x
+ return z
+}
+
+// satan reduces its argument (known to be positive)
+// to the range [0, 0.66] and calls xatan.
+func satan(x float64) float64 {
+ const (
+ Morebits = 6.123233995736765886130e-17 // pi/2 = PIO2 + Morebits
+ Tan3pio8 = 2.41421356237309504880 // tan(3*pi/8)
+ )
+ if x <= 0.66 {
+ return xatan(x)
+ }
+ if x > Tan3pio8 {
+ return Pi/2 - xatan(1/x) + Morebits
+ }
+ return Pi/4 + xatan((x-1)/(x+1)) + 0.5*Morebits
+}
+
+// Atan returns the arctangent, in radians, of x.
+//
+// Special cases are:
+//
+// Atan(±0) = ±0
+// Atan(±Inf) = ±Pi/2
+func Atan(x float64) float64 {
+ if haveArchAtan {
+ return archAtan(x)
+ }
+ return atan(x)
+}
+
+func atan(x float64) float64 {
+ if x == 0 {
+ return x
+ }
+ if x > 0 {
+ return satan(x)
+ }
+ return -satan(-x)
+}
diff --git a/go/src/math/atan2.go b/go/src/math/atan2.go
new file mode 100644
index 0000000000000000000000000000000000000000..c324ed0a1578a25195586ebc448d11374824e23d
--- /dev/null
+++ b/go/src/math/atan2.go
@@ -0,0 +1,77 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Atan2 returns the arc tangent of y/x, using
+// the signs of the two to determine the quadrant
+// of the return value.
+//
+// Special cases are (in order):
+//
+// Atan2(y, NaN) = NaN
+// Atan2(NaN, x) = NaN
+// Atan2(+0, x>=0) = +0
+// Atan2(-0, x>=0) = -0
+// Atan2(+0, x<=-0) = +Pi
+// Atan2(-0, x<=-0) = -Pi
+// Atan2(y>0, 0) = +Pi/2
+// Atan2(y<0, 0) = -Pi/2
+// Atan2(+Inf, +Inf) = +Pi/4
+// Atan2(-Inf, +Inf) = -Pi/4
+// Atan2(+Inf, -Inf) = 3Pi/4
+// Atan2(-Inf, -Inf) = -3Pi/4
+// Atan2(y, +Inf) = 0
+// Atan2(y>0, -Inf) = +Pi
+// Atan2(y<0, -Inf) = -Pi
+// Atan2(+Inf, x) = +Pi/2
+// Atan2(-Inf, x) = -Pi/2
+func Atan2(y, x float64) float64 {
+ if haveArchAtan2 {
+ return archAtan2(y, x)
+ }
+ return atan2(y, x)
+}
+
+func atan2(y, x float64) float64 {
+ // special cases
+ switch {
+ case IsNaN(y) || IsNaN(x):
+ return NaN()
+ case y == 0:
+ if x >= 0 && !Signbit(x) {
+ return Copysign(0, y)
+ }
+ return Copysign(Pi, y)
+ case x == 0:
+ return Copysign(Pi/2, y)
+ case IsInf(x, 0):
+ if IsInf(x, 1) {
+ switch {
+ case IsInf(y, 0):
+ return Copysign(Pi/4, y)
+ default:
+ return Copysign(0, y)
+ }
+ }
+ switch {
+ case IsInf(y, 0):
+ return Copysign(3*Pi/4, y)
+ default:
+ return Copysign(Pi, y)
+ }
+ case IsInf(y, 0):
+ return Copysign(Pi/2, y)
+ }
+
+ // Call atan and determine the quadrant.
+ q := Atan(y / x)
+ if x < 0 {
+ if q <= 0 {
+ return q + Pi
+ }
+ return q - Pi
+ }
+ return q
+}
diff --git a/go/src/math/atan2_s390x.s b/go/src/math/atan2_s390x.s
new file mode 100644
index 0000000000000000000000000000000000000000..13ff31977b5376676c0aa622286a8ff6b0a8d719
--- /dev/null
+++ b/go/src/math/atan2_s390x.s
@@ -0,0 +1,297 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+#define PosInf 0x7FF0000000000000
+#define NegInf 0xFFF0000000000000
+#define NegZero 0x8000000000000000
+#define Pi 0x400921FB54442D18
+#define NegPi 0xC00921FB54442D18
+#define Pi3Div4 0x4002D97C7F3321D2 // 3Pi/4
+#define NegPi3Div4 0xC002D97C7F3321D2 // -3Pi/4
+#define PiDiv4 0x3FE921FB54442D18 // Pi/4
+#define NegPiDiv4 0xBFE921FB54442D18 // -Pi/4
+
+// Minimax polynomial coefficients and other constants
+DATA ·atan2rodataL25<> + 0(SB)/8, $0.199999999999554423E+00
+DATA ·atan2rodataL25<> + 8(SB)/8, $-.333333333333330928E+00
+DATA ·atan2rodataL25<> + 16(SB)/8, $0.111111110136634272E+00
+DATA ·atan2rodataL25<> + 24(SB)/8, $-.142857142828026806E+00
+DATA ·atan2rodataL25<> + 32(SB)/8, $0.769228118888682505E-01
+DATA ·atan2rodataL25<> + 40(SB)/8, $0.588059263575587687E-01
+DATA ·atan2rodataL25<> + 48(SB)/8, $-.909090711945939878E-01
+DATA ·atan2rodataL25<> + 56(SB)/8, $-.666641501287528609E-01
+DATA ·atan2rodataL25<> + 64(SB)/8, $0.472329433805024762E-01
+DATA ·atan2rodataL25<> + 72(SB)/8, $-.525380587584426406E-01
+DATA ·atan2rodataL25<> + 80(SB)/8, $-.422172007412067035E-01
+DATA ·atan2rodataL25<> + 88(SB)/8, $0.366935664549587481E-01
+DATA ·atan2rodataL25<> + 96(SB)/8, $0.220852012160300086E-01
+DATA ·atan2rodataL25<> + 104(SB)/8, $-.299856214685512712E-01
+DATA ·atan2rodataL25<> + 112(SB)/8, $0.726338160757602439E-02
+DATA ·atan2rodataL25<> + 120(SB)/8, $0.134893651284712515E-04
+DATA ·atan2rodataL25<> + 128(SB)/8, $-.291935324869629616E-02
+DATA ·atan2rodataL25<> + 136(SB)/8, $-.154797890856877418E-03
+DATA ·atan2rodataL25<> + 144(SB)/8, $0.843488472994227321E-03
+DATA ·atan2rodataL25<> + 152(SB)/8, $-.139950258898989925E-01
+GLOBL ·atan2rodataL25<> + 0(SB), RODATA, $160
+
+DATA ·atan2xpi2h<> + 0(SB)/8, $0x3ff330e4e4fa7b1b
+DATA ·atan2xpi2h<> + 8(SB)/8, $0xbff330e4e4fa7b1b
+DATA ·atan2xpi2h<> + 16(SB)/8, $0x400330e4e4fa7b1b
+DATA ·atan2xpi2h<> + 24(SB)/8, $0xc00330e4e4fa7b1b
+GLOBL ·atan2xpi2h<> + 0(SB), RODATA, $32
+DATA ·atan2xpim<> + 0(SB)/8, $0x3ff4f42b00000000
+GLOBL ·atan2xpim<> + 0(SB), RODATA, $8
+
+// Atan2 returns the arc tangent of y/x, using
+// the signs of the two to determine the quadrant
+// of the return value.
+//
+// Special cases are (in order):
+// Atan2(y, NaN) = NaN
+// Atan2(NaN, x) = NaN
+// Atan2(+0, x>=0) = +0
+// Atan2(-0, x>=0) = -0
+// Atan2(+0, x<=-0) = +Pi
+// Atan2(-0, x<=-0) = -Pi
+// Atan2(y>0, 0) = +Pi/2
+// Atan2(y<0, 0) = -Pi/2
+// Atan2(+Inf, +Inf) = +Pi/4
+// Atan2(-Inf, +Inf) = -Pi/4
+// Atan2(+Inf, -Inf) = 3Pi/4
+// Atan2(-Inf, -Inf) = -3Pi/4
+// Atan2(y, +Inf) = 0
+// Atan2(y>0, -Inf) = +Pi
+// Atan2(y<0, -Inf) = -Pi
+// Atan2(+Inf, x) = +Pi/2
+// Atan2(-Inf, x) = -Pi/2
+// The algorithm used is minimax polynomial approximation
+// with coefficients determined with a Remez exchange algorithm.
+
+TEXT ·atan2Asm(SB), NOSPLIT, $0-24
+ // special case
+ MOVD x+0(FP), R1
+ MOVD y+8(FP), R2
+
+ // special case Atan2(NaN, y) = NaN
+ MOVD $~(1<<63), R5
+ AND R1, R5 // x = |x|
+ MOVD $PosInf, R3
+ CMPUBLT R3, R5, returnX
+
+ // special case Atan2(x, NaN) = NaN
+ MOVD $~(1<<63), R5
+ AND R2, R5
+ CMPUBLT R3, R5, returnY
+
+ MOVD $NegZero, R3
+ CMPUBEQ R3, R1, xIsNegZero
+
+ MOVD $0, R3
+ CMPUBEQ R3, R1, xIsPosZero
+
+ MOVD $PosInf, R4
+ CMPUBEQ R4, R2, yIsPosInf
+
+ MOVD $NegInf, R4
+ CMPUBEQ R4, R2, yIsNegInf
+ BR Normal
+xIsNegZero:
+ // special case Atan(-0, y>=0) = -0
+ MOVD $0, R4
+ CMPBLE R4, R2, returnX
+
+ //special case Atan2(-0, y<=-0) = -Pi
+ MOVD $NegZero, R4
+ CMPBGE R4, R2, returnNegPi
+ BR Normal
+xIsPosZero:
+ //special case Atan2(0, 0) = 0
+ MOVD $0, R4
+ CMPUBEQ R4, R2, returnX
+
+ //special case Atan2(0, y<=-0) = Pi
+ MOVD $NegZero, R4
+ CMPBGE R4, R2, returnPi
+ BR Normal
+yIsNegInf:
+ //special case Atan2(+Inf, -Inf) = 3Pi/4
+ MOVD $PosInf, R3
+ CMPUBEQ R3, R1, posInfNegInf
+
+ //special case Atan2(-Inf, -Inf) = -3Pi/4
+ MOVD $NegInf, R3
+ CMPUBEQ R3, R1, negInfNegInf
+ BR Normal
+yIsPosInf:
+ //special case Atan2(+Inf, +Inf) = Pi/4
+ MOVD $PosInf, R3
+ CMPUBEQ R3, R1, posInfPosInf
+
+ //special case Atan2(-Inf, +Inf) = -Pi/4
+ MOVD $NegInf, R3
+ CMPUBEQ R3, R1, negInfPosInf
+
+ //special case Atan2(x, +Inf) = Copysign(0, x)
+ CMPBLT R1, $0, returnNegZero
+ BR returnPosZero
+
+Normal:
+ FMOVD x+0(FP), F0
+ FMOVD y+8(FP), F2
+ MOVD $·atan2rodataL25<>+0(SB), R9
+ LGDR F0, R2
+ LGDR F2, R1
+ RISBGNZ $32, $63, $32, R2, R2
+ RISBGNZ $32, $63, $32, R1, R1
+ WORD $0xB9170032 //llgtr %r3,%r2
+ RISBGZ $63, $63, $33, R2, R5
+ WORD $0xB9170041 //llgtr %r4,%r1
+ WFLCDB V0, V20
+ MOVW R4, R6
+ MOVW R3, R7
+ CMPUBLT R6, R7, L17
+ WFDDB V2, V0, V3
+ ADDW $2, R5, R2
+ MOVW R4, R6
+ MOVW R3, R7
+ CMPUBLE R6, R7, L20
+L3:
+ WFMDB V3, V3, V4
+ VLEG $0, 152(R9), V18
+ VLEG $0, 144(R9), V16
+ FMOVD 136(R9), F1
+ FMOVD 128(R9), F5
+ FMOVD 120(R9), F6
+ WFMADB V4, V16, V5, V16
+ WFMADB V4, V6, V1, V6
+ FMOVD 112(R9), F7
+ WFMDB V4, V4, V1
+ WFMADB V4, V7, V18, V7
+ VLEG $0, 104(R9), V18
+ WFMADB V1, V6, V16, V6
+ CMPWU R4, R3
+ FMOVD 96(R9), F5
+ VLEG $0, 88(R9), V16
+ WFMADB V4, V5, V18, V5
+ VLEG $0, 80(R9), V18
+ VLEG $0, 72(R9), V22
+ WFMADB V4, V16, V18, V16
+ VLEG $0, 64(R9), V18
+ WFMADB V1, V7, V5, V7
+ WFMADB V4, V18, V22, V18
+ WFMDB V1, V1, V5
+ WFMADB V1, V16, V18, V16
+ VLEG $0, 56(R9), V18
+ WFMADB V5, V6, V7, V6
+ VLEG $0, 48(R9), V22
+ FMOVD 40(R9), F7
+ WFMADB V4, V7, V18, V7
+ VLEG $0, 32(R9), V18
+ WFMADB V5, V6, V16, V6
+ WFMADB V4, V18, V22, V18
+ VLEG $0, 24(R9), V16
+ WFMADB V1, V7, V18, V7
+ VLEG $0, 16(R9), V18
+ VLEG $0, 8(R9), V22
+ WFMADB V4, V18, V16, V18
+ VLEG $0, 0(R9), V16
+ WFMADB V5, V6, V7, V6
+ WFMADB V4, V16, V22, V16
+ FMUL F3, F4
+ WFMADB V1, V18, V16, V1
+ FMADD F6, F5, F1
+ WFMADB V4, V1, V3, V4
+ BLT L18
+ BGT L7
+ LTDBR F2, F2
+ BLTU L21
+L8:
+ LTDBR F0, F0
+ BLTU L22
+L9:
+ WFCHDBS V2, V0, V0
+ BNE L18
+L7:
+ MOVW R1, R6
+ CMPBGE R6, $0, L1
+L18:
+ RISBGZ $58, $60, $3, R2, R2
+ MOVD $·atan2xpi2h<>+0(SB), R1
+ MOVD ·atan2xpim<>+0(SB), R3
+ LDGR R3, F0
+ WORD $0xED021000 //madb %f4,%f0,0(%r2,%r1)
+ BYTE $0x40
+ BYTE $0x1E
+L1:
+ FMOVD F4, ret+16(FP)
+ RET
+
+L20:
+ LTDBR F2, F2
+ BLTU L23
+ FMOVD F2, F6
+L4:
+ LTDBR F0, F0
+ BLTU L24
+ FMOVD F0, F4
+L5:
+ WFCHDBS V6, V4, V4
+ BEQ L3
+L17:
+ WFDDB V0, V2, V4
+ BYTE $0x18 //lr %r2,%r5
+ BYTE $0x25
+ LCDBR F4, F3
+ BR L3
+L23:
+ LCDBR F2, F6
+ BR L4
+L22:
+ VLR V20, V0
+ BR L9
+L21:
+ LCDBR F2, F2
+ BR L8
+L24:
+ VLR V20, V4
+ BR L5
+returnX: //the result is same as the first argument
+ MOVD R1, ret+16(FP)
+ RET
+returnY: //the result is same as the second argument
+ MOVD R2, ret+16(FP)
+ RET
+returnPi:
+ MOVD $Pi, R1
+ MOVD R1, ret+16(FP)
+ RET
+returnNegPi:
+ MOVD $NegPi, R1
+ MOVD R1, ret+16(FP)
+ RET
+posInfNegInf:
+ MOVD $Pi3Div4, R1
+ MOVD R1, ret+16(FP)
+ RET
+negInfNegInf:
+ MOVD $NegPi3Div4, R1
+ MOVD R1, ret+16(FP)
+ RET
+posInfPosInf:
+ MOVD $PiDiv4, R1
+ MOVD R1, ret+16(FP)
+ RET
+negInfPosInf:
+ MOVD $NegPiDiv4, R1
+ MOVD R1, ret+16(FP)
+ RET
+returnNegZero:
+ MOVD $NegZero, R1
+ MOVD R1, ret+16(FP)
+ RET
+returnPosZero:
+ MOVD $0, ret+16(FP)
+ RET
diff --git a/go/src/math/atan_s390x.s b/go/src/math/atan_s390x.s
new file mode 100644
index 0000000000000000000000000000000000000000..3a7e59bb1ac62852663cbcbdee31c72e9ad11428
--- /dev/null
+++ b/go/src/math/atan_s390x.s
@@ -0,0 +1,128 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// Minimax polynomial coefficients and other constants
+DATA ·atanrodataL8<> + 0(SB)/8, $0.199999999999554423E+00
+DATA ·atanrodataL8<> + 8(SB)/8, $0.111111110136634272E+00
+DATA ·atanrodataL8<> + 16(SB)/8, $-.142857142828026806E+00
+DATA ·atanrodataL8<> + 24(SB)/8, $-.333333333333330928E+00
+DATA ·atanrodataL8<> + 32(SB)/8, $0.769228118888682505E-01
+DATA ·atanrodataL8<> + 40(SB)/8, $0.588059263575587687E-01
+DATA ·atanrodataL8<> + 48(SB)/8, $-.666641501287528609E-01
+DATA ·atanrodataL8<> + 56(SB)/8, $-.909090711945939878E-01
+DATA ·atanrodataL8<> + 64(SB)/8, $0.472329433805024762E-01
+DATA ·atanrodataL8<> + 72(SB)/8, $0.366935664549587481E-01
+DATA ·atanrodataL8<> + 80(SB)/8, $-.422172007412067035E-01
+DATA ·atanrodataL8<> + 88(SB)/8, $-.299856214685512712E-01
+DATA ·atanrodataL8<> + 96(SB)/8, $0.220852012160300086E-01
+DATA ·atanrodataL8<> + 104(SB)/8, $0.726338160757602439E-02
+DATA ·atanrodataL8<> + 112(SB)/8, $0.843488472994227321E-03
+DATA ·atanrodataL8<> + 120(SB)/8, $0.134893651284712515E-04
+DATA ·atanrodataL8<> + 128(SB)/8, $-.525380587584426406E-01
+DATA ·atanrodataL8<> + 136(SB)/8, $-.139950258898989925E-01
+DATA ·atanrodataL8<> + 144(SB)/8, $-.291935324869629616E-02
+DATA ·atanrodataL8<> + 152(SB)/8, $-.154797890856877418E-03
+GLOBL ·atanrodataL8<> + 0(SB), RODATA, $160
+
+DATA ·atanxpi2h<> + 0(SB)/8, $0x3ff330e4e4fa7b1b
+DATA ·atanxpi2h<> + 8(SB)/8, $0xbff330e4e4fa7b1b
+DATA ·atanxpi2h<> + 16(SB)/8, $0x400330e4e4fa7b1b
+DATA ·atanxpi2h<> + 24(SB)/4, $0xc00330e4e4fa7b1b
+GLOBL ·atanxpi2h<> + 0(SB), RODATA, $32
+DATA ·atanxpim<> + 0(SB)/8, $0x3ff4f42b00000000
+GLOBL ·atanxpim<> + 0(SB), RODATA, $8
+DATA ·atanxmone<> + 0(SB)/8, $-1.0
+GLOBL ·atanxmone<> + 0(SB), RODATA, $8
+
+// Atan returns the arctangent, in radians, of the argument.
+//
+// Special cases are:
+// Atan(±0) = ±0
+// Atan(±Inf) = ±Pi/2Pi
+// The algorithm used is minimax polynomial approximation
+// with coefficients determined with a Remez exchange algorithm.
+
+TEXT ·atanAsm(SB), NOSPLIT, $0-16
+ FMOVD x+0(FP), F0
+ //special case Atan(±0) = ±0
+ FMOVD $(0.0), F1
+ FCMPU F0, F1
+ BEQ atanIsZero
+
+ MOVD $·atanrodataL8<>+0(SB), R5
+ MOVH $0x3FE0, R3
+ LGDR F0, R1
+ RISBGNZ $32, $63, $32, R1, R1
+ RLL $16, R1, R2
+ ANDW $0x7FF0, R2
+ MOVW R2, R6
+ MOVW R3, R7
+ CMPUBLE R6, R7, L6
+ MOVD $·atanxmone<>+0(SB), R3
+ FMOVD 0(R3), F2
+ WFDDB V0, V2, V0
+ RISBGZ $63, $63, $33, R1, R1
+ MOVD $·atanxpi2h<>+0(SB), R3
+ MOVWZ R1, R1
+ SLD $3, R1, R1
+ WORD $0x68813000 //ld %f8,0(%r1,%r3)
+L6:
+ WFMDB V0, V0, V2
+ FMOVD 152(R5), F6
+ FMOVD 144(R5), F1
+ FMOVD 136(R5), F7
+ VLEG $0, 128(R5), V16
+ FMOVD 120(R5), F4
+ FMOVD 112(R5), F5
+ WFMADB V2, V4, V6, V4
+ WFMADB V2, V5, V1, V5
+ WFMDB V2, V2, V6
+ FMOVD 104(R5), F3
+ FMOVD 96(R5), F1
+ WFMADB V2, V3, V7, V3
+ MOVH $0x3FE0, R1
+ FMOVD 88(R5), F7
+ WFMADB V2, V1, V7, V1
+ FMOVD 80(R5), F7
+ WFMADB V6, V3, V1, V3
+ WFMADB V6, V4, V5, V4
+ WFMDB V6, V6, V1
+ FMOVD 72(R5), F5
+ WFMADB V2, V5, V7, V5
+ FMOVD 64(R5), F7
+ WFMADB V2, V7, V16, V7
+ VLEG $0, 56(R5), V16
+ WFMADB V6, V5, V7, V5
+ WFMADB V1, V4, V3, V4
+ FMOVD 48(R5), F7
+ FMOVD 40(R5), F3
+ WFMADB V2, V3, V7, V3
+ FMOVD 32(R5), F7
+ WFMADB V2, V7, V16, V7
+ VLEG $0, 24(R5), V16
+ WFMADB V1, V4, V5, V4
+ FMOVD 16(R5), F5
+ WFMADB V6, V3, V7, V3
+ FMOVD 8(R5), F7
+ WFMADB V2, V7, V5, V7
+ FMOVD 0(R5), F5
+ WFMADB V2, V5, V16, V5
+ WFMADB V1, V4, V3, V4
+ WFMADB V6, V7, V5, V6
+ FMUL F0, F2
+ FMADD F4, F1, F6
+ FMADD F6, F2, F0
+ MOVW R2, R6
+ MOVW R1, R7
+ CMPUBLE R6, R7, L1
+ MOVD $·atanxpim<>+0(SB), R1
+ WORD $0xED801000 //madb %f0,%f8,0(%r1)
+ BYTE $0x00
+ BYTE $0x1E
+L1:
+atanIsZero:
+ FMOVD F0, ret+8(FP)
+ RET
diff --git a/go/src/math/atanh.go b/go/src/math/atanh.go
new file mode 100644
index 0000000000000000000000000000000000000000..9d594625a5c04a41954d3bf2fbef2d078751ad11
--- /dev/null
+++ b/go/src/math/atanh.go
@@ -0,0 +1,85 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// The original C code, the long comment, and the constants
+// below are from FreeBSD's /usr/src/lib/msun/src/e_atanh.c
+// and came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+//
+// __ieee754_atanh(x)
+// Method :
+// 1. Reduce x to positive by atanh(-x) = -atanh(x)
+// 2. For x>=0.5
+// 1 2x x
+// atanh(x) = --- * log(1 + -------) = 0.5 * log1p(2 * --------)
+// 2 1 - x 1 - x
+//
+// For x<0.5
+// atanh(x) = 0.5*log1p(2x+2x*x/(1-x))
+//
+// Special cases:
+// atanh(x) is NaN if |x| > 1 with signal;
+// atanh(NaN) is that NaN with no signal;
+// atanh(+-1) is +-INF with signal.
+//
+
+// Atanh returns the inverse hyperbolic tangent of x.
+//
+// Special cases are:
+//
+// Atanh(1) = +Inf
+// Atanh(±0) = ±0
+// Atanh(-1) = -Inf
+// Atanh(x) = NaN if x < -1 or x > 1
+// Atanh(NaN) = NaN
+func Atanh(x float64) float64 {
+ if haveArchAtanh {
+ return archAtanh(x)
+ }
+ return atanh(x)
+}
+
+func atanh(x float64) float64 {
+ const NearZero = 1.0 / (1 << 28) // 2**-28
+ // special cases
+ switch {
+ case x < -1 || x > 1 || IsNaN(x):
+ return NaN()
+ case x == 1:
+ return Inf(1)
+ case x == -1:
+ return Inf(-1)
+ }
+ sign := false
+ if x < 0 {
+ x = -x
+ sign = true
+ }
+ var temp float64
+ switch {
+ case x < NearZero:
+ temp = x
+ case x < 0.5:
+ temp = x + x
+ temp = 0.5 * Log1p(temp+temp*x/(1-x))
+ default:
+ temp = 0.5 * Log1p((x+x)/(1-x))
+ }
+ if sign {
+ temp = -temp
+ }
+ return temp
+}
diff --git a/go/src/math/atanh_s390x.s b/go/src/math/atanh_s390x.s
new file mode 100644
index 0000000000000000000000000000000000000000..ba0e92696720b3c95c1ebfd5a99594b42c17afe8
--- /dev/null
+++ b/go/src/math/atanh_s390x.s
@@ -0,0 +1,174 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// Minimax polynomial coefficients and other constants
+DATA ·atanhrodataL10<> + 0(SB)/8, $.41375273347623353626
+DATA ·atanhrodataL10<> + 8(SB)/8, $.51487302528619766235E+04
+DATA ·atanhrodataL10<> + 16(SB)/8, $-1.67526912689208984375
+DATA ·atanhrodataL10<> + 24(SB)/8, $0.181818181818181826E+00
+DATA ·atanhrodataL10<> + 32(SB)/8, $-.165289256198351540E-01
+DATA ·atanhrodataL10<> + 40(SB)/8, $0.200350613573012186E-02
+DATA ·atanhrodataL10<> + 48(SB)/8, $0.397389654305194527E-04
+DATA ·atanhrodataL10<> + 56(SB)/8, $-.273205381970859341E-03
+DATA ·atanhrodataL10<> + 64(SB)/8, $0.938370938292558173E-06
+DATA ·atanhrodataL10<> + 72(SB)/8, $-.148682720127920854E-06
+DATA ·atanhrodataL10<> + 80(SB)/8, $ 0.212881813645679599E-07
+DATA ·atanhrodataL10<> + 88(SB)/8, $-.602107458843052029E-05
+DATA ·atanhrodataL10<> + 96(SB)/8, $-5.5
+DATA ·atanhrodataL10<> + 104(SB)/8, $-0.5
+DATA ·atanhrodataL10<> + 112(SB)/8, $0.0
+DATA ·atanhrodataL10<> + 120(SB)/8, $0x7ff8000000000000 //Nan
+DATA ·atanhrodataL10<> + 128(SB)/8, $-1.0
+DATA ·atanhrodataL10<> + 136(SB)/8, $1.0
+DATA ·atanhrodataL10<> + 144(SB)/8, $1.0E-20
+GLOBL ·atanhrodataL10<> + 0(SB), RODATA, $152
+
+// Table of log correction terms
+DATA ·atanhtab2076<> + 0(SB)/8, $0.585235384085551248E-01
+DATA ·atanhtab2076<> + 8(SB)/8, $0.412206153771168640E-01
+DATA ·atanhtab2076<> + 16(SB)/8, $0.273839003221648339E-01
+DATA ·atanhtab2076<> + 24(SB)/8, $0.166383778368856480E-01
+DATA ·atanhtab2076<> + 32(SB)/8, $0.866678223433169637E-02
+DATA ·atanhtab2076<> + 40(SB)/8, $0.319831684989627514E-02
+DATA ·atanhtab2076<> + 48(SB)/8, $0.000000000000000000E+00
+DATA ·atanhtab2076<> + 56(SB)/8, $-.113006378583725549E-02
+DATA ·atanhtab2076<> + 64(SB)/8, $-.367979419636602491E-03
+DATA ·atanhtab2076<> + 72(SB)/8, $0.213172484510484979E-02
+DATA ·atanhtab2076<> + 80(SB)/8, $0.623271047682013536E-02
+DATA ·atanhtab2076<> + 88(SB)/8, $0.118140812789696885E-01
+DATA ·atanhtab2076<> + 96(SB)/8, $0.187681358930914206E-01
+DATA ·atanhtab2076<> + 104(SB)/8, $0.269985148668178992E-01
+DATA ·atanhtab2076<> + 112(SB)/8, $0.364186619761331328E-01
+DATA ·atanhtab2076<> + 120(SB)/8, $0.469505379381388441E-01
+GLOBL ·atanhtab2076<> + 0(SB), RODATA, $128
+
+// Table of +/- .5
+DATA ·atanhtabh2075<> + 0(SB)/8, $0.5
+DATA ·atanhtabh2075<> + 8(SB)/8, $-.5
+GLOBL ·atanhtabh2075<> + 0(SB), RODATA, $16
+
+// Atanh returns the inverse hyperbolic tangent of the argument.
+//
+// Special cases are:
+// Atanh(1) = +Inf
+// Atanh(±0) = ±0
+// Atanh(-1) = -Inf
+// Atanh(x) = NaN if x < -1 or x > 1
+// Atanh(NaN) = NaN
+// The algorithm used is minimax polynomial approximation
+// with coefficients determined with a Remez exchange algorithm.
+
+TEXT ·atanhAsm(SB), NOSPLIT, $0-16
+ FMOVD x+0(FP), F0
+ MOVD $·atanhrodataL10<>+0(SB), R5
+ LGDR F0, R1
+ WORD $0xC0393FEF //iilf %r3,1072693247
+ BYTE $0xFF
+ BYTE $0xFF
+ SRAD $32, R1
+ WORD $0xB9170021 //llgtr %r2,%r1
+ MOVW R2, R6
+ MOVW R3, R7
+ CMPBGT R6, R7, L2
+ WORD $0xC0392FFF //iilf %r3,805306367
+ BYTE $0xFF
+ BYTE $0xFF
+ MOVW R2, R6
+ MOVW R3, R7
+ CMPBGT R6, R7, L9
+L3:
+ FMOVD 144(R5), F2
+ FMADD F2, F0, F0
+L1:
+ FMOVD F0, ret+8(FP)
+ RET
+
+L2:
+ WORD $0xED005088 //cdb %f0,.L12-.L10(%r5)
+ BYTE $0x00
+ BYTE $0x19
+ BEQ L5
+ WORD $0xED005080 //cdb %f0,.L13-.L10(%r5)
+ BYTE $0x00
+ BYTE $0x19
+ BEQ L5
+ WFCEDBS V0, V0, V2
+ BVS L1
+ FMOVD 120(R5), F0
+ BR L1
+L5:
+ WORD $0xED005070 //ddb %f0,.L15-.L10(%r5)
+ BYTE $0x00
+ BYTE $0x1D
+ FMOVD F0, ret+8(FP)
+ RET
+
+L9:
+ FMOVD F0, F2
+ MOVD $·atanhtabh2075<>+0(SB), R2
+ SRW $31, R1, R1
+ FMOVD 104(R5), F4
+ MOVW R1, R1
+ SLD $3, R1, R1
+ WORD $0x68012000 //ld %f0,0(%r1,%r2)
+ WFMADB V2, V4, V0, V4
+ VLEG $0, 96(R5), V16
+ FDIV F4, F2
+ WORD $0xC0298006 //iilf %r2,2147909631
+ BYTE $0x7F
+ BYTE $0xFF
+ FMOVD 88(R5), F6
+ FMOVD 80(R5), F1
+ FMOVD 72(R5), F7
+ FMOVD 64(R5), F5
+ FMOVD F2, F4
+ WORD $0xED405088 //adb %f4,.L12-.L10(%r5)
+ BYTE $0x00
+ BYTE $0x1A
+ LGDR F4, R4
+ SRAD $32, R4
+ FMOVD F4, F3
+ WORD $0xED305088 //sdb %f3,.L12-.L10(%r5)
+ BYTE $0x00
+ BYTE $0x1B
+ SUBW R4, R2
+ WFSDB V3, V2, V3
+ RISBGZ $32, $47, $0, R2, R1
+ SLD $32, R1, R1
+ LDGR R1, F2
+ WFMADB V4, V2, V16, V4
+ SRAW $8, R2, R1
+ WFMADB V4, V5, V6, V5
+ WFMDB V4, V4, V6
+ WFMADB V4, V1, V7, V1
+ WFMADB V2, V3, V4, V2
+ WFMADB V1, V6, V5, V1
+ FMOVD 56(R5), F3
+ FMOVD 48(R5), F5
+ WFMADB V4, V5, V3, V4
+ FMOVD 40(R5), F3
+ FMADD F1, F6, F4
+ FMOVD 32(R5), F1
+ FMADD F3, F2, F1
+ ANDW $0xFFFFFF00, R1
+ WFMADB V6, V4, V1, V6
+ FMOVD 24(R5), F3
+ ORW $0x45000000, R1
+ WFMADB V2, V6, V3, V6
+ VLVGF $0, R1, V4
+ LDEBR F4, F4
+ RISBGZ $57, $60, $51, R2, R2
+ MOVD $·atanhtab2076<>+0(SB), R1
+ FMOVD 16(R5), F3
+ WORD $0x68521000 //ld %f5,0(%r2,%r1)
+ FMOVD 8(R5), F1
+ WFMADB V2, V6, V5, V2
+ WFMADB V4, V3, V1, V4
+ FMOVD 0(R5), F6
+ FMADD F6, F4, F2
+ FMUL F2, F0
+ FMOVD F0, ret+8(FP)
+ RET
diff --git a/go/src/math/bits.go b/go/src/math/bits.go
new file mode 100644
index 0000000000000000000000000000000000000000..3716a411f4f1b81bb99f441f0102ab3082e8477b
--- /dev/null
+++ b/go/src/math/bits.go
@@ -0,0 +1,67 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+const (
+ uvnan = 0x7FF8000000000001
+ uvinf = 0x7FF0000000000000
+ uvneginf = 0xFFF0000000000000
+ uvone = 0x3FF0000000000000
+ mask = 0x7FF
+ shift = 64 - 11 - 1
+ bias = 1023
+ signMask = 1 << 63
+ fracMask = 1<= 0, negative infinity if sign < 0.
+func Inf(sign int) float64 {
+ var v uint64
+ if sign >= 0 {
+ v = uvinf
+ } else {
+ v = uvneginf
+ }
+ return Float64frombits(v)
+}
+
+// NaN returns an IEEE 754 “not-a-number” value.
+func NaN() float64 { return Float64frombits(uvnan) }
+
+// IsNaN reports whether f is an IEEE 754 “not-a-number” value.
+func IsNaN(f float64) (is bool) {
+ // IEEE 754 says that only NaNs satisfy f != f.
+ // To avoid the floating-point hardware, could use:
+ // x := Float64bits(f);
+ // return uint32(x>>shift)&mask == mask && x != uvinf && x != uvneginf
+ return f != f
+}
+
+// IsInf reports whether f is an infinity, according to sign.
+// If sign > 0, IsInf reports whether f is positive infinity.
+// If sign < 0, IsInf reports whether f is negative infinity.
+// If sign == 0, IsInf reports whether f is either infinity.
+func IsInf(f float64, sign int) bool {
+ // Test for infinity by comparing against maximum float.
+ // To avoid the floating-point hardware, could use:
+ // x := Float64bits(f);
+ // return sign >= 0 && x == uvinf || sign <= 0 && x == uvneginf;
+ if sign == 0 {
+ f = Abs(f)
+ } else if sign < 0 {
+ f = -f
+ }
+ return f > MaxFloat64
+}
+
+// normalize returns a normal number y and exponent exp
+// satisfying x == y × 2**exp. It assumes x is finite and non-zero.
+func normalize(x float64) (y float64, exp int) {
+ const SmallestNormal = 2.2250738585072014e-308 // 2**-1022
+ if Abs(x) < SmallestNormal {
+ return x * (1 << 52), -52
+ }
+ return x, 0
+}
diff --git a/go/src/math/cbrt.go b/go/src/math/cbrt.go
new file mode 100644
index 0000000000000000000000000000000000000000..e5e9548cb1f39489df6d8185b5e8c36b6e72876e
--- /dev/null
+++ b/go/src/math/cbrt.go
@@ -0,0 +1,85 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// The go code is a modified version of the original C code from
+// http://www.netlib.org/fdlibm/s_cbrt.c and came with this notice.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunSoft, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+
+// Cbrt returns the cube root of x.
+//
+// Special cases are:
+//
+// Cbrt(±0) = ±0
+// Cbrt(±Inf) = ±Inf
+// Cbrt(NaN) = NaN
+func Cbrt(x float64) float64 {
+ if haveArchCbrt {
+ return archCbrt(x)
+ }
+ return cbrt(x)
+}
+
+func cbrt(x float64) float64 {
+ const (
+ B1 = 715094163 // (682-0.03306235651)*2**20
+ B2 = 696219795 // (664-0.03306235651)*2**20
+ C = 5.42857142857142815906e-01 // 19/35 = 0x3FE15F15F15F15F1
+ D = -7.05306122448979611050e-01 // -864/1225 = 0xBFE691DE2532C834
+ E = 1.41428571428571436819e+00 // 99/70 = 0x3FF6A0EA0EA0EA0F
+ F = 1.60714285714285720630e+00 // 45/28 = 0x3FF9B6DB6DB6DB6E
+ G = 3.57142857142857150787e-01 // 5/14 = 0x3FD6DB6DB6DB6DB7
+ SmallestNormal = 2.22507385850720138309e-308 // 2**-1022 = 0x0010000000000000
+ )
+ // special cases
+ switch {
+ case x == 0 || IsNaN(x) || IsInf(x, 0):
+ return x
+ }
+
+ sign := false
+ if x < 0 {
+ x = -x
+ sign = true
+ }
+
+ // rough cbrt to 5 bits
+ t := Float64frombits(Float64bits(x)/3 + B1<<32)
+ if x < SmallestNormal {
+ // subnormal number
+ t = float64(1 << 54) // set t= 2**54
+ t *= x
+ t = Float64frombits(Float64bits(t)/3 + B2<<32)
+ }
+
+ // new cbrt to 23 bits
+ r := t * t / x
+ s := C + r*t
+ t *= G + F/(s+E+D/s)
+
+ // chop to 22 bits, make larger than cbrt(x)
+ t = Float64frombits(Float64bits(t)&(0xFFFFFFFFC<<28) + 1<<30)
+
+ // one step newton iteration to 53 bits with error less than 0.667ulps
+ s = t * t // t*t is exact
+ r = x / s
+ w := t + t
+ r = (r - t) / (w + r) // r-s is exact
+ t = t + t*r
+
+ // restore the sign bit
+ if sign {
+ t = -t
+ }
+ return t
+}
diff --git a/go/src/math/cbrt_s390x.s b/go/src/math/cbrt_s390x.s
new file mode 100644
index 0000000000000000000000000000000000000000..87bba531b8cb8d9c38edbf650cf74d599e2c4c0e
--- /dev/null
+++ b/go/src/math/cbrt_s390x.s
@@ -0,0 +1,156 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// Minimax polynomial coefficients and other constants
+DATA ·cbrtrodataL9<> + 0(SB)/8, $-.00016272731015974436E+00
+DATA ·cbrtrodataL9<> + 8(SB)/8, $0.66639548758285293179E+00
+DATA ·cbrtrodataL9<> + 16(SB)/8, $0.55519402697349815993E+00
+DATA ·cbrtrodataL9<> + 24(SB)/8, $0.49338566048766782004E+00
+DATA ·cbrtrodataL9<> + 32(SB)/8, $0.45208160036325611486E+00
+DATA ·cbrtrodataL9<> + 40(SB)/8, $0.43099892837778637816E+00
+DATA ·cbrtrodataL9<> + 48(SB)/8, $1.000244140625
+DATA ·cbrtrodataL9<> + 56(SB)/8, $0.33333333333333333333E+00
+DATA ·cbrtrodataL9<> + 64(SB)/8, $79228162514264337593543950336.
+GLOBL ·cbrtrodataL9<> + 0(SB), RODATA, $72
+
+// Index tables
+DATA ·cbrttab32069<> + 0(SB)/8, $0x404030303020202
+DATA ·cbrttab32069<> + 8(SB)/8, $0x101010101000000
+DATA ·cbrttab32069<> + 16(SB)/8, $0x808070706060605
+DATA ·cbrttab32069<> + 24(SB)/8, $0x505040404040303
+DATA ·cbrttab32069<> + 32(SB)/8, $0xe0d0c0c0b0b0b0a
+DATA ·cbrttab32069<> + 40(SB)/8, $0xa09090908080808
+DATA ·cbrttab32069<> + 48(SB)/8, $0x11111010100f0f0f
+DATA ·cbrttab32069<> + 56(SB)/8, $0xe0e0e0e0e0d0d0d
+DATA ·cbrttab32069<> + 64(SB)/8, $0x1515141413131312
+DATA ·cbrttab32069<> + 72(SB)/8, $0x1212111111111010
+GLOBL ·cbrttab32069<> + 0(SB), RODATA, $80
+
+DATA ·cbrttab22068<> + 0(SB)/8, $0x151015001420141
+DATA ·cbrttab22068<> + 8(SB)/8, $0x140013201310130
+DATA ·cbrttab22068<> + 16(SB)/8, $0x122012101200112
+DATA ·cbrttab22068<> + 24(SB)/8, $0x111011001020101
+DATA ·cbrttab22068<> + 32(SB)/8, $0x10000f200f100f0
+DATA ·cbrttab22068<> + 40(SB)/8, $0xe200e100e000d2
+DATA ·cbrttab22068<> + 48(SB)/8, $0xd100d000c200c1
+DATA ·cbrttab22068<> + 56(SB)/8, $0xc000b200b100b0
+DATA ·cbrttab22068<> + 64(SB)/8, $0xa200a100a00092
+DATA ·cbrttab22068<> + 72(SB)/8, $0x91009000820081
+DATA ·cbrttab22068<> + 80(SB)/8, $0x80007200710070
+DATA ·cbrttab22068<> + 88(SB)/8, $0x62006100600052
+DATA ·cbrttab22068<> + 96(SB)/8, $0x51005000420041
+DATA ·cbrttab22068<> + 104(SB)/8, $0x40003200310030
+DATA ·cbrttab22068<> + 112(SB)/8, $0x22002100200012
+DATA ·cbrttab22068<> + 120(SB)/8, $0x11001000020001
+GLOBL ·cbrttab22068<> + 0(SB), RODATA, $128
+
+DATA ·cbrttab12067<> + 0(SB)/8, $0x53e1529051324fe1
+DATA ·cbrttab12067<> + 8(SB)/8, $0x4e904d324be14a90
+DATA ·cbrttab12067<> + 16(SB)/8, $0x493247e146904532
+DATA ·cbrttab12067<> + 24(SB)/8, $0x43e1429041323fe1
+DATA ·cbrttab12067<> + 32(SB)/8, $0x3e903d323be13a90
+DATA ·cbrttab12067<> + 40(SB)/8, $0x393237e136903532
+DATA ·cbrttab12067<> + 48(SB)/8, $0x33e1329031322fe1
+DATA ·cbrttab12067<> + 56(SB)/8, $0x2e902d322be12a90
+DATA ·cbrttab12067<> + 64(SB)/8, $0xd3e1d290d132cfe1
+DATA ·cbrttab12067<> + 72(SB)/8, $0xce90cd32cbe1ca90
+DATA ·cbrttab12067<> + 80(SB)/8, $0xc932c7e1c690c532
+DATA ·cbrttab12067<> + 88(SB)/8, $0xc3e1c290c132bfe1
+DATA ·cbrttab12067<> + 96(SB)/8, $0xbe90bd32bbe1ba90
+DATA ·cbrttab12067<> + 104(SB)/8, $0xb932b7e1b690b532
+DATA ·cbrttab12067<> + 112(SB)/8, $0xb3e1b290b132afe1
+DATA ·cbrttab12067<> + 120(SB)/8, $0xae90ad32abe1aa90
+GLOBL ·cbrttab12067<> + 0(SB), RODATA, $128
+
+// Cbrt returns the cube root of the argument.
+//
+// Special cases are:
+// Cbrt(±0) = ±0
+// Cbrt(±Inf) = ±Inf
+// Cbrt(NaN) = NaN
+// The algorithm used is minimax polynomial approximation
+// with coefficients determined with a Remez exchange algorithm.
+
+TEXT ·cbrtAsm(SB), NOSPLIT, $0-16
+ FMOVD x+0(FP), F0
+ MOVD $·cbrtrodataL9<>+0(SB), R9
+ LGDR F0, R2
+ WORD $0xC039000F //iilf %r3,1048575
+ BYTE $0xFF
+ BYTE $0xFF
+ SRAD $32, R2
+ WORD $0xB9170012 //llgtr %r1,%r2
+ MOVW R1, R6
+ MOVW R3, R7
+ CMPBLE R6, R7, L2
+ WORD $0xC0397FEF //iilf %r3,2146435071
+ BYTE $0xFF
+ BYTE $0xFF
+ MOVW R3, R7
+ CMPBLE R6, R7, L8
+L1:
+ FMOVD F0, ret+8(FP)
+ RET
+L3:
+L2:
+ LTDBR F0, F0
+ BEQ L1
+ FMOVD F0, F2
+ WORD $0xED209040 //mdb %f2,.L10-.L9(%r9)
+ BYTE $0x00
+ BYTE $0x1C
+ MOVH $0x200, R4
+ LGDR F2, R2
+ SRAD $32, R2
+L4:
+ RISBGZ $57, $62, $39, R2, R3
+ MOVD $·cbrttab12067<>+0(SB), R1
+ WORD $0x48131000 //lh %r1,0(%r3,%r1)
+ RISBGZ $57, $62, $45, R2, R3
+ MOVD $·cbrttab22068<>+0(SB), R5
+ RISBGNZ $60, $63, $48, R2, R2
+ WORD $0x4A135000 //ah %r1,0(%r3,%r5)
+ BYTE $0x18 //lr %r3,%r1
+ BYTE $0x31
+ MOVD $·cbrttab32069<>+0(SB), R1
+ FMOVD 56(R9), F1
+ FMOVD 48(R9), F5
+ WORD $0xEC23393B //rosbg %r2,%r3,57,59,4
+ BYTE $0x04
+ BYTE $0x56
+ WORD $0xE3121000 //llc %r1,0(%r2,%r1)
+ BYTE $0x00
+ BYTE $0x94
+ ADDW R3, R1
+ ADDW R4, R1
+ SLW $16, R1, R1
+ SLD $32, R1, R1
+ LDGR R1, F2
+ WFMDB V2, V2, V4
+ WFMDB V4, V0, V6
+ WFMSDB V4, V6, V2, V4
+ FMOVD 40(R9), F6
+ FMSUB F1, F4, F2
+ FMOVD 32(R9), F4
+ WFMDB V2, V2, V3
+ FMOVD 24(R9), F1
+ FMUL F3, F0
+ FMOVD 16(R9), F3
+ WFMADB V2, V0, V5, V2
+ FMOVD 8(R9), F5
+ FMADD F6, F2, F4
+ WFMADB V2, V1, V3, V1
+ WFMDB V2, V2, V6
+ FMOVD 0(R9), F3
+ WFMADB V4, V6, V1, V4
+ WFMADB V2, V5, V3, V2
+ FMADD F4, F6, F2
+ FMADD F2, F0, F0
+ FMOVD F0, ret+8(FP)
+ RET
+L8:
+ MOVH $0x0, R4
+ BR L4
diff --git a/go/src/math/const.go b/go/src/math/const.go
new file mode 100644
index 0000000000000000000000000000000000000000..b15e50e01820837acc344aa5646e1633f07dc8f1
--- /dev/null
+++ b/go/src/math/const.go
@@ -0,0 +1,57 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package math provides basic constants and mathematical functions.
+//
+// This package does not guarantee bit-identical results across architectures.
+package math
+
+// Mathematical constants.
+const (
+ E = 2.71828182845904523536028747135266249775724709369995957496696763 // https://oeis.org/A001113
+ Pi = 3.14159265358979323846264338327950288419716939937510582097494459 // https://oeis.org/A000796
+ Phi = 1.61803398874989484820458683436563811772030917980576286213544862 // https://oeis.org/A001622
+
+ Sqrt2 = 1.41421356237309504880168872420969807856967187537694807317667974 // https://oeis.org/A002193
+ SqrtE = 1.64872127070012814684865078781416357165377610071014801157507931 // https://oeis.org/A019774
+ SqrtPi = 1.77245385090551602729816748334114518279754945612238712821380779 // https://oeis.org/A002161
+ SqrtPhi = 1.27201964951406896425242246173749149171560804184009624861664038 // https://oeis.org/A139339
+
+ Ln2 = 0.693147180559945309417232121458176568075500134360255254120680009 // https://oeis.org/A002162
+ Log2E = 1 / Ln2
+ Ln10 = 2.30258509299404568401799145468436420760110148862877297603332790 // https://oeis.org/A002392
+ Log10E = 1 / Ln10
+)
+
+// Floating-point limit values.
+// Max is the largest finite value representable by the type.
+// SmallestNonzero is the smallest positive, non-zero value representable by the type.
+const (
+ MaxFloat32 = 0x1p127 * (1 + (1 - 0x1p-23)) // 3.40282346638528859811704183484516925440e+38
+ SmallestNonzeroFloat32 = 0x1p-126 * 0x1p-23 // 1.401298464324817070923729583289916131280e-45
+
+ MaxFloat64 = 0x1p1023 * (1 + (1 - 0x1p-52)) // 1.79769313486231570814527423731704356798070e+308
+ SmallestNonzeroFloat64 = 0x1p-1022 * 0x1p-52 // 4.9406564584124654417656879286822137236505980e-324
+)
+
+// Integer limit values.
+const (
+ intSize = 32 << (^uint(0) >> 63) // 32 or 64
+
+ MaxInt = 1<<(intSize-1) - 1 // MaxInt32 or MaxInt64 depending on intSize.
+ MinInt = -1 << (intSize - 1) // MinInt32 or MinInt64 depending on intSize.
+ MaxInt8 = 1<<7 - 1 // 127
+ MinInt8 = -1 << 7 // -128
+ MaxInt16 = 1<<15 - 1 // 32767
+ MinInt16 = -1 << 15 // -32768
+ MaxInt32 = 1<<31 - 1 // 2147483647
+ MinInt32 = -1 << 31 // -2147483648
+ MaxInt64 = 1<<63 - 1 // 9223372036854775807
+ MinInt64 = -1 << 63 // -9223372036854775808
+ MaxUint = 1<+0(SB)/8, $0.231904681384629956E-16
+DATA coshrodataL23<>+8(SB)/8, $0.693147180559945286E+00
+DATA coshrodataL23<>+16(SB)/8, $0.144269504088896339E+01
+DATA coshrodataL23<>+24(SB)/8, $704.E0
+GLOBL coshrodataL23<>+0(SB), RODATA, $32
+DATA coshxinf<>+0(SB)/8, $0x7FF0000000000000
+GLOBL coshxinf<>+0(SB), RODATA, $8
+DATA coshxlim1<>+0(SB)/8, $800.E0
+GLOBL coshxlim1<>+0(SB), RODATA, $8
+DATA coshxaddhy<>+0(SB)/8, $0xc2f0000100003fdf
+GLOBL coshxaddhy<>+0(SB), RODATA, $8
+DATA coshx4ff<>+0(SB)/8, $0x4ff0000000000000
+GLOBL coshx4ff<>+0(SB), RODATA, $8
+DATA coshe1<>+0(SB)/8, $0x3ff000000000000a
+GLOBL coshe1<>+0(SB), RODATA, $8
+
+// Log multiplier table
+DATA coshtab<>+0(SB)/8, $0.442737824274138381E-01
+DATA coshtab<>+8(SB)/8, $0.263602189790660309E-01
+DATA coshtab<>+16(SB)/8, $0.122565642281703586E-01
+DATA coshtab<>+24(SB)/8, $0.143757052860721398E-02
+DATA coshtab<>+32(SB)/8, $-.651375034121276075E-02
+DATA coshtab<>+40(SB)/8, $-.119317678849450159E-01
+DATA coshtab<>+48(SB)/8, $-.150868749549871069E-01
+DATA coshtab<>+56(SB)/8, $-.161992609578469234E-01
+DATA coshtab<>+64(SB)/8, $-.154492360403337917E-01
+DATA coshtab<>+72(SB)/8, $-.129850717389178721E-01
+DATA coshtab<>+80(SB)/8, $-.892902649276657891E-02
+DATA coshtab<>+88(SB)/8, $-.338202636596794887E-02
+DATA coshtab<>+96(SB)/8, $0.357266307045684762E-02
+DATA coshtab<>+104(SB)/8, $0.118665304327406698E-01
+DATA coshtab<>+112(SB)/8, $0.214434994118118914E-01
+DATA coshtab<>+120(SB)/8, $0.322580645161290314E-01
+GLOBL coshtab<>+0(SB), RODATA, $128
+
+// Minimax polynomial approximations
+DATA coshe2<>+0(SB)/8, $0.500000000000004237e+00
+GLOBL coshe2<>+0(SB), RODATA, $8
+DATA coshe3<>+0(SB)/8, $0.166666666630345592e+00
+GLOBL coshe3<>+0(SB), RODATA, $8
+DATA coshe4<>+0(SB)/8, $0.416666664838056960e-01
+GLOBL coshe4<>+0(SB), RODATA, $8
+DATA coshe5<>+0(SB)/8, $0.833349307718286047e-02
+GLOBL coshe5<>+0(SB), RODATA, $8
+DATA coshe6<>+0(SB)/8, $0.138926439368309441e-02
+GLOBL coshe6<>+0(SB), RODATA, $8
+
+// Cosh returns the hyperbolic cosine of x.
+//
+// Special cases are:
+// Cosh(±0) = 1
+// Cosh(±Inf) = +Inf
+// Cosh(NaN) = NaN
+// The algorithm used is minimax polynomial approximation
+// with coefficients determined with a Remez exchange algorithm.
+
+TEXT ·coshAsm(SB),NOSPLIT,$0-16
+ FMOVD x+0(FP), F0
+ MOVD $coshrodataL23<>+0(SB), R9
+ LTDBR F0, F0
+ MOVD $0x4086000000000000, R2
+ MOVD $0x4086000000000000, R3
+ BLTU L19
+ FMOVD F0, F4
+L2:
+ WORD $0xED409018 //cdb %f4,.L24-.L23(%r9)
+ BYTE $0x00
+ BYTE $0x19
+ BGE L14 //jnl .L14
+ BVS L14
+ WFCEDBS V4, V4, V2
+ BEQ L20
+L1:
+ FMOVD F0, ret+8(FP)
+ RET
+
+L14:
+ WFCEDBS V4, V4, V2
+ BVS L1
+ MOVD $coshxlim1<>+0(SB), R1
+ FMOVD 0(R1), F2
+ WFCHEDBS V4, V2, V2
+ BEQ L21
+ MOVD $coshxaddhy<>+0(SB), R1
+ FMOVD coshrodataL23<>+16(SB), F5
+ FMOVD 0(R1), F2
+ WFMSDB V0, V5, V2, V5
+ FMOVD coshrodataL23<>+8(SB), F3
+ FADD F5, F2
+ MOVD $coshe6<>+0(SB), R1
+ WFMSDB V2, V3, V0, V3
+ FMOVD 0(R1), F6
+ WFMDB V3, V3, V1
+ MOVD $coshe4<>+0(SB), R1
+ FMOVD coshrodataL23<>+0(SB), F7
+ WFMADB V2, V7, V3, V2
+ FMOVD 0(R1), F3
+ MOVD $coshe5<>+0(SB), R1
+ WFMADB V1, V6, V3, V6
+ FMOVD 0(R1), F7
+ MOVD $coshe3<>+0(SB), R1
+ FMOVD 0(R1), F3
+ WFMADB V1, V7, V3, V7
+ FNEG F2, F3
+ LGDR F5, R1
+ MOVD $coshe2<>+0(SB), R3
+ WFCEDBS V4, V0, V0
+ FMOVD 0(R3), F5
+ MOVD $coshe1<>+0(SB), R3
+ WFMADB V1, V6, V5, V6
+ FMOVD 0(R3), F5
+ RISBGN $0, $15, $48, R1, R2
+ WFMADB V1, V7, V5, V1
+ BVS L22
+ RISBGZ $57, $60, $3, R1, R4
+ MOVD $coshtab<>+0(SB), R3
+ WFMADB V3, V6, V1, V6
+ WORD $0x68043000 //ld %f0,0(%r4,%r3)
+ FMSUB F0, F3, F2
+ WORD $0xA71AF000 //ahi %r1,-4096
+ WFMADB V2, V6, V0, V6
+L17:
+ RISBGN $0, $15, $48, R1, R2
+ LDGR R2, F2
+ FMADD F2, F6, F2
+ MOVD $coshx4ff<>+0(SB), R1
+ FMOVD 0(R1), F0
+ FMUL F2, F0
+ FMOVD F0, ret+8(FP)
+ RET
+
+L19:
+ FNEG F0, F4
+ BR L2
+L20:
+ MOVD $coshxaddhy<>+0(SB), R1
+ FMOVD coshrodataL23<>+16(SB), F3
+ FMOVD 0(R1), F2
+ WFMSDB V0, V3, V2, V3
+ FMOVD coshrodataL23<>+8(SB), F4
+ FADD F3, F2
+ MOVD $coshe6<>+0(SB), R1
+ FMSUB F4, F2, F0
+ FMOVD 0(R1), F6
+ WFMDB V0, V0, V1
+ MOVD $coshe4<>+0(SB), R1
+ FMOVD 0(R1), F4
+ MOVD $coshe5<>+0(SB), R1
+ FMOVD coshrodataL23<>+0(SB), F5
+ WFMADB V1, V6, V4, V6
+ FMADD F5, F2, F0
+ FMOVD 0(R1), F2
+ MOVD $coshe3<>+0(SB), R1
+ FMOVD 0(R1), F4
+ WFMADB V1, V2, V4, V2
+ MOVD $coshe2<>+0(SB), R1
+ FMOVD 0(R1), F5
+ FNEG F0, F4
+ WFMADB V1, V6, V5, V6
+ MOVD $coshe1<>+0(SB), R1
+ FMOVD 0(R1), F5
+ WFMADB V1, V2, V5, V1
+ LGDR F3, R1
+ MOVD $coshtab<>+0(SB), R5
+ WFMADB V4, V6, V1, V3
+ RISBGZ $57, $60, $3, R1, R4
+ WFMSDB V4, V6, V1, V6
+ WORD $0x68145000 //ld %f1,0(%r4,%r5)
+ WFMSDB V4, V1, V0, V2
+ WORD $0xA7487FBE //lhi %r4,32702
+ FMADD F3, F2, F1
+ SUBW R1, R4
+ RISBGZ $57, $60, $3, R4, R12
+ WORD $0x682C5000 //ld %f2,0(%r12,%r5)
+ FMSUB F2, F4, F0
+ RISBGN $0, $15, $48, R1, R2
+ WFMADB V0, V6, V2, V6
+ RISBGN $0, $15, $48, R4, R3
+ LDGR R2, F2
+ LDGR R3, F0
+ FMADD F2, F1, F2
+ FMADD F0, F6, F0
+ FADD F2, F0
+ FMOVD F0, ret+8(FP)
+ RET
+
+L22:
+ WORD $0xA7387FBE //lhi %r3,32702
+ MOVD $coshtab<>+0(SB), R4
+ SUBW R1, R3
+ WFMSDB V3, V6, V1, V6
+ RISBGZ $57, $60, $3, R3, R3
+ WORD $0x68034000 //ld %f0,0(%r3,%r4)
+ FMSUB F0, F3, F2
+ WORD $0xA7386FBE //lhi %r3,28606
+ WFMADB V2, V6, V0, V6
+ SUBW R1, R3, R1
+ BR L17
+L21:
+ MOVD $coshxinf<>+0(SB), R1
+ FMOVD 0(R1), F0
+ FMOVD F0, ret+8(FP)
+ RET
+
diff --git a/go/src/math/dim.go b/go/src/math/dim.go
new file mode 100644
index 0000000000000000000000000000000000000000..f369f70f000fbb69823dfe987af6b6ac0191c756
--- /dev/null
+++ b/go/src/math/dim.go
@@ -0,0 +1,100 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Dim returns the maximum of x-y or 0.
+//
+// Special cases are:
+//
+// Dim(+Inf, +Inf) = NaN
+// Dim(-Inf, -Inf) = NaN
+// Dim(x, NaN) = Dim(NaN, x) = NaN
+func Dim(x, y float64) float64 {
+ // The special cases result in NaN after the subtraction:
+ // +Inf - +Inf = NaN
+ // -Inf - -Inf = NaN
+ // NaN - y = NaN
+ // x - NaN = NaN
+ v := x - y
+ if v <= 0 {
+ // v is negative or 0
+ return 0
+ }
+ // v is positive or NaN
+ return v
+}
+
+// Max returns the larger of x or y.
+//
+// Special cases are:
+//
+// Max(x, +Inf) = Max(+Inf, x) = +Inf
+// Max(x, NaN) = Max(NaN, x) = NaN
+// Max(+0, ±0) = Max(±0, +0) = +0
+// Max(-0, -0) = -0
+//
+// Note that this differs from the built-in function max when called
+// with NaN and +Inf.
+func Max(x, y float64) float64 {
+ if haveArchMax {
+ return archMax(x, y)
+ }
+ return max(x, y)
+}
+
+func max(x, y float64) float64 {
+ // special cases
+ switch {
+ case IsInf(x, 1) || IsInf(y, 1):
+ return Inf(1)
+ case IsNaN(x) || IsNaN(y):
+ return NaN()
+ case x == 0 && x == y:
+ if Signbit(x) {
+ return y
+ }
+ return x
+ }
+ if x > y {
+ return x
+ }
+ return y
+}
+
+// Min returns the smaller of x or y.
+//
+// Special cases are:
+//
+// Min(x, -Inf) = Min(-Inf, x) = -Inf
+// Min(x, NaN) = Min(NaN, x) = NaN
+// Min(-0, ±0) = Min(±0, -0) = -0
+//
+// Note that this differs from the built-in function min when called
+// with NaN and -Inf.
+func Min(x, y float64) float64 {
+ if haveArchMin {
+ return archMin(x, y)
+ }
+ return min(x, y)
+}
+
+func min(x, y float64) float64 {
+ // special cases
+ switch {
+ case IsInf(x, -1) || IsInf(y, -1):
+ return Inf(-1)
+ case IsNaN(x) || IsNaN(y):
+ return NaN()
+ case x == 0 && x == y:
+ if Signbit(x) {
+ return x
+ }
+ return y
+ }
+ if x < y {
+ return x
+ }
+ return y
+}
diff --git a/go/src/math/dim_amd64.s b/go/src/math/dim_amd64.s
new file mode 100644
index 0000000000000000000000000000000000000000..253f03b97e713314a6ffa395f7a92b69e16ee634
--- /dev/null
+++ b/go/src/math/dim_amd64.s
@@ -0,0 +1,98 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+#define PosInf 0x7FF0000000000000
+#define NaN 0x7FF8000000000001
+#define NegInf 0xFFF0000000000000
+
+// func ·archMax(x, y float64) float64
+TEXT ·archMax(SB),NOSPLIT,$0
+ // +Inf special cases
+ MOVQ $PosInf, AX
+ MOVQ x+0(FP), R8
+ CMPQ AX, R8
+ JEQ isPosInf
+ MOVQ y+8(FP), R9
+ CMPQ AX, R9
+ JEQ isPosInf
+ // NaN special cases
+ MOVQ $~(1<<63), DX // bit mask
+ MOVQ $PosInf, AX
+ MOVQ R8, BX
+ ANDQ DX, BX // x = |x|
+ CMPQ AX, BX
+ JLT isMaxNaN
+ MOVQ R9, CX
+ ANDQ DX, CX // y = |y|
+ CMPQ AX, CX
+ JLT isMaxNaN
+ // ±0 special cases
+ ORQ CX, BX
+ JEQ isMaxZero
+
+ MOVQ R8, X0
+ MOVQ R9, X1
+ MAXSD X1, X0
+ MOVSD X0, ret+16(FP)
+ RET
+isMaxNaN: // return NaN
+ MOVQ $NaN, AX
+isPosInf: // return +Inf
+ MOVQ AX, ret+16(FP)
+ RET
+isMaxZero:
+ MOVQ $(1<<63), AX // -0.0
+ CMPQ AX, R8
+ JEQ +3(PC)
+ MOVQ R8, ret+16(FP) // return 0
+ RET
+ MOVQ R9, ret+16(FP) // return other 0
+ RET
+
+// func archMin(x, y float64) float64
+TEXT ·archMin(SB),NOSPLIT,$0
+ // -Inf special cases
+ MOVQ $NegInf, AX
+ MOVQ x+0(FP), R8
+ CMPQ AX, R8
+ JEQ isNegInf
+ MOVQ y+8(FP), R9
+ CMPQ AX, R9
+ JEQ isNegInf
+ // NaN special cases
+ MOVQ $~(1<<63), DX
+ MOVQ $PosInf, AX
+ MOVQ R8, BX
+ ANDQ DX, BX // x = |x|
+ CMPQ AX, BX
+ JLT isMinNaN
+ MOVQ R9, CX
+ ANDQ DX, CX // y = |y|
+ CMPQ AX, CX
+ JLT isMinNaN
+ // ±0 special cases
+ ORQ CX, BX
+ JEQ isMinZero
+
+ MOVQ R8, X0
+ MOVQ R9, X1
+ MINSD X1, X0
+ MOVSD X0, ret+16(FP)
+ RET
+isMinNaN: // return NaN
+ MOVQ $NaN, AX
+isNegInf: // return -Inf
+ MOVQ AX, ret+16(FP)
+ RET
+isMinZero:
+ MOVQ $(1<<63), AX // -0.0
+ CMPQ AX, R8
+ JEQ +3(PC)
+ MOVQ R9, ret+16(FP) // return other 0
+ RET
+ MOVQ R8, ret+16(FP) // return -0
+ RET
+
diff --git a/go/src/math/dim_arm64.s b/go/src/math/dim_arm64.s
new file mode 100644
index 0000000000000000000000000000000000000000..f112003dc0f615a23e1ebecbb9ef946fa953e6e1
--- /dev/null
+++ b/go/src/math/dim_arm64.s
@@ -0,0 +1,49 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+#define PosInf 0x7FF0000000000000
+#define NaN 0x7FF8000000000001
+#define NegInf 0xFFF0000000000000
+
+// func ·archMax(x, y float64) float64
+TEXT ·archMax(SB),NOSPLIT,$0
+ // +Inf special cases
+ MOVD $PosInf, R0
+ MOVD x+0(FP), R1
+ CMP R0, R1
+ BEQ isPosInf
+ MOVD y+8(FP), R2
+ CMP R0, R2
+ BEQ isPosInf
+ // normal case
+ FMOVD R1, F0
+ FMOVD R2, F1
+ FMAXD F0, F1, F0
+ FMOVD F0, ret+16(FP)
+ RET
+isPosInf: // return +Inf
+ MOVD R0, ret+16(FP)
+ RET
+
+// func archMin(x, y float64) float64
+TEXT ·archMin(SB),NOSPLIT,$0
+ // -Inf special cases
+ MOVD $NegInf, R0
+ MOVD x+0(FP), R1
+ CMP R0, R1
+ BEQ isNegInf
+ MOVD y+8(FP), R2
+ CMP R0, R2
+ BEQ isNegInf
+ // normal case
+ FMOVD R1, F0
+ FMOVD R2, F1
+ FMIND F0, F1, F0
+ FMOVD F0, ret+16(FP)
+ RET
+isNegInf: // return -Inf
+ MOVD R0, ret+16(FP)
+ RET
diff --git a/go/src/math/dim_asm.go b/go/src/math/dim_asm.go
new file mode 100644
index 0000000000000000000000000000000000000000..a1d23dd0962b07cc72b983e37218abaf5f6085ef
--- /dev/null
+++ b/go/src/math/dim_asm.go
@@ -0,0 +1,15 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build amd64 || arm64 || loong64 || riscv64 || s390x
+
+package math
+
+const haveArchMax = true
+
+func archMax(x, y float64) float64
+
+const haveArchMin = true
+
+func archMin(x, y float64) float64
diff --git a/go/src/math/dim_loong64.s b/go/src/math/dim_loong64.s
new file mode 100644
index 0000000000000000000000000000000000000000..1484bf7638112348f83105834010a63a70ec99cf
--- /dev/null
+++ b/go/src/math/dim_loong64.s
@@ -0,0 +1,77 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+#define PosInf 0x7FF0000000000000
+#define NaN 0x7FF8000000000001
+#define NegInf 0xFFF0000000000000
+
+TEXT ·archMax(SB),NOSPLIT,$0
+ MOVD x+0(FP), F0
+ MOVD y+8(FP), F1
+ FCLASSD F0, F2
+ FCLASSD F1, F3
+
+ // combine x and y categories together to judge
+ MOVV F2, R4
+ MOVV F3, R5
+ OR R5, R4
+
+ // +Inf special cases
+ AND $64, R4, R5
+ BNE R5, isPosInf
+
+ // NaN special cases
+ AND $2, R4, R5
+ BNE R5, isMaxNaN
+
+ // normal case
+ FMAXD F0, F1, F0
+ MOVD F0, ret+16(FP)
+ RET
+
+isMaxNaN:
+ MOVV $NaN, R6
+ MOVV R6, ret+16(FP)
+ RET
+
+isPosInf:
+ MOVV $PosInf, R6
+ MOVV R6, ret+16(FP)
+ RET
+
+TEXT ·archMin(SB),NOSPLIT,$0
+ MOVD x+0(FP), F0
+ MOVD y+8(FP), F1
+ FCLASSD F0, F2
+ FCLASSD F1, F3
+
+ // combine x and y categories together to judge
+ MOVV F2, R4
+ MOVV F3, R5
+ OR R5, R4
+
+ // -Inf special cases
+ AND $4, R4, R5
+ BNE R5, isNegInf
+
+ // NaN special cases
+ AND $2, R4, R5
+ BNE R5, isMinNaN
+
+ // normal case
+ FMIND F0, F1, F0
+ MOVD F0, ret+16(FP)
+ RET
+
+isMinNaN:
+ MOVV $NaN, R6
+ MOVV R6, ret+16(FP)
+ RET
+
+isNegInf:
+ MOVV $NegInf, R6
+ MOVV R6, ret+16(FP)
+ RET
diff --git a/go/src/math/dim_noasm.go b/go/src/math/dim_noasm.go
new file mode 100644
index 0000000000000000000000000000000000000000..6f4917b8e8247b58152ee5d8123f9e7e600e82ea
--- /dev/null
+++ b/go/src/math/dim_noasm.go
@@ -0,0 +1,19 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !amd64 && !arm64 && !loong64 && !riscv64 && !s390x
+
+package math
+
+const haveArchMax = false
+
+func archMax(x, y float64) float64 {
+ panic("not implemented")
+}
+
+const haveArchMin = false
+
+func archMin(x, y float64) float64 {
+ panic("not implemented")
+}
diff --git a/go/src/math/dim_riscv64.s b/go/src/math/dim_riscv64.s
new file mode 100644
index 0000000000000000000000000000000000000000..5b2fd3d0633f47514e570c90797d7f7039f76c2b
--- /dev/null
+++ b/go/src/math/dim_riscv64.s
@@ -0,0 +1,70 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// Values returned from an FCLASS instruction.
+#define NegInf 0x001
+#define PosInf 0x080
+#define NaN 0x200
+
+// func archMax(x, y float64) float64
+TEXT ·archMax(SB),NOSPLIT,$0
+ MOVD x+0(FP), F0
+ MOVD y+8(FP), F1
+ FCLASSD F0, X5
+ FCLASSD F1, X6
+
+ // +Inf special cases
+ MOV $PosInf, X7
+ BEQ X7, X5, isMaxX
+ BEQ X7, X6, isMaxY
+
+ // NaN special cases
+ MOV $NaN, X7
+ BEQ X7, X5, isMaxX
+ BEQ X7, X6, isMaxY
+
+ // normal case
+ FMAXD F0, F1, F0
+ MOVD F0, ret+16(FP)
+ RET
+
+isMaxX: // return x
+ MOVD F0, ret+16(FP)
+ RET
+
+isMaxY: // return y
+ MOVD F1, ret+16(FP)
+ RET
+
+// func archMin(x, y float64) float64
+TEXT ·archMin(SB),NOSPLIT,$0
+ MOVD x+0(FP), F0
+ MOVD y+8(FP), F1
+ FCLASSD F0, X5
+ FCLASSD F1, X6
+
+ // -Inf special cases
+ MOV $NegInf, X7
+ BEQ X7, X5, isMinX
+ BEQ X7, X6, isMinY
+
+ // NaN special cases
+ MOV $NaN, X7
+ BEQ X7, X5, isMinX
+ BEQ X7, X6, isMinY
+
+ // normal case
+ FMIND F0, F1, F0
+ MOVD F0, ret+16(FP)
+ RET
+
+isMinX: // return x
+ MOVD F0, ret+16(FP)
+ RET
+
+isMinY: // return y
+ MOVD F1, ret+16(FP)
+ RET
diff --git a/go/src/math/dim_s390x.s b/go/src/math/dim_s390x.s
new file mode 100644
index 0000000000000000000000000000000000000000..12770261f2e78d325f770f7e5af7aaa6f049a76b
--- /dev/null
+++ b/go/src/math/dim_s390x.s
@@ -0,0 +1,96 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Based on dim_amd64.s
+
+#include "textflag.h"
+
+#define PosInf 0x7FF0000000000000
+#define NaN 0x7FF8000000000001
+#define NegInf 0xFFF0000000000000
+
+// func ·Max(x, y float64) float64
+TEXT ·archMax(SB),NOSPLIT,$0
+ // +Inf special cases
+ MOVD $PosInf, R4
+ MOVD x+0(FP), R8
+ CMPUBEQ R4, R8, isPosInf
+ MOVD y+8(FP), R9
+ CMPUBEQ R4, R9, isPosInf
+ // NaN special cases
+ MOVD $~(1<<63), R5 // bit mask
+ MOVD $PosInf, R4
+ MOVD R8, R2
+ AND R5, R2 // x = |x|
+ CMPUBLT R4, R2, isMaxNaN
+ MOVD R9, R3
+ AND R5, R3 // y = |y|
+ CMPUBLT R4, R3, isMaxNaN
+ // ±0 special cases
+ OR R3, R2
+ BEQ isMaxZero
+
+ FMOVD x+0(FP), F1
+ FMOVD y+8(FP), F2
+ FCMPU F2, F1
+ BGT +3(PC)
+ FMOVD F1, ret+16(FP)
+ RET
+ FMOVD F2, ret+16(FP)
+ RET
+isMaxNaN: // return NaN
+ MOVD $NaN, R4
+isPosInf: // return +Inf
+ MOVD R4, ret+16(FP)
+ RET
+isMaxZero:
+ MOVD $(1<<63), R4 // -0.0
+ CMPUBEQ R4, R8, +3(PC)
+ MOVD R8, ret+16(FP) // return 0
+ RET
+ MOVD R9, ret+16(FP) // return other 0
+ RET
+
+// func archMin(x, y float64) float64
+TEXT ·archMin(SB),NOSPLIT,$0
+ // -Inf special cases
+ MOVD $NegInf, R4
+ MOVD x+0(FP), R8
+ CMPUBEQ R4, R8, isNegInf
+ MOVD y+8(FP), R9
+ CMPUBEQ R4, R9, isNegInf
+ // NaN special cases
+ MOVD $~(1<<63), R5
+ MOVD $PosInf, R4
+ MOVD R8, R2
+ AND R5, R2 // x = |x|
+ CMPUBLT R4, R2, isMinNaN
+ MOVD R9, R3
+ AND R5, R3 // y = |y|
+ CMPUBLT R4, R3, isMinNaN
+ // ±0 special cases
+ OR R3, R2
+ BEQ isMinZero
+
+ FMOVD x+0(FP), F1
+ FMOVD y+8(FP), F2
+ FCMPU F2, F1
+ BLT +3(PC)
+ FMOVD F1, ret+16(FP)
+ RET
+ FMOVD F2, ret+16(FP)
+ RET
+isMinNaN: // return NaN
+ MOVD $NaN, R4
+isNegInf: // return -Inf
+ MOVD R4, ret+16(FP)
+ RET
+isMinZero:
+ MOVD $(1<<63), R4 // -0.0
+ CMPUBEQ R4, R8, +3(PC)
+ MOVD R9, ret+16(FP) // return other 0
+ RET
+ MOVD R8, ret+16(FP) // return -0
+ RET
+
diff --git a/go/src/math/erf.go b/go/src/math/erf.go
new file mode 100644
index 0000000000000000000000000000000000000000..ba00c7d03edc1101c4705cc6b79649b5c094e556
--- /dev/null
+++ b/go/src/math/erf.go
@@ -0,0 +1,351 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+ Floating-point error function and complementary error function.
+*/
+
+// The original C code and the long comment below are
+// from FreeBSD's /usr/src/lib/msun/src/s_erf.c and
+// came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+//
+// double erf(double x)
+// double erfc(double x)
+// x
+// 2 |\
+// erf(x) = --------- | exp(-t*t)dt
+// sqrt(pi) \|
+// 0
+//
+// erfc(x) = 1-erf(x)
+// Note that
+// erf(-x) = -erf(x)
+// erfc(-x) = 2 - erfc(x)
+//
+// Method:
+// 1. For |x| in [0, 0.84375]
+// erf(x) = x + x*R(x**2)
+// erfc(x) = 1 - erf(x) if x in [-.84375,0.25]
+// = 0.5 + ((0.5-x)-x*R) if x in [0.25,0.84375]
+// where R = P/Q where P is an odd poly of degree 8 and
+// Q is an odd poly of degree 10.
+// -57.90
+// | R - (erf(x)-x)/x | <= 2
+//
+//
+// Remark. The formula is derived by noting
+// erf(x) = (2/sqrt(pi))*(x - x**3/3 + x**5/10 - x**7/42 + ....)
+// and that
+// 2/sqrt(pi) = 1.128379167095512573896158903121545171688
+// is close to one. The interval is chosen because the fix
+// point of erf(x) is near 0.6174 (i.e., erf(x)=x when x is
+// near 0.6174), and by some experiment, 0.84375 is chosen to
+// guarantee the error is less than one ulp for erf.
+//
+// 2. For |x| in [0.84375,1.25], let s = |x| - 1, and
+// c = 0.84506291151 rounded to single (24 bits)
+// erf(x) = sign(x) * (c + P1(s)/Q1(s))
+// erfc(x) = (1-c) - P1(s)/Q1(s) if x > 0
+// 1+(c+P1(s)/Q1(s)) if x < 0
+// |P1/Q1 - (erf(|x|)-c)| <= 2**-59.06
+// Remark: here we use the taylor series expansion at x=1.
+// erf(1+s) = erf(1) + s*Poly(s)
+// = 0.845.. + P1(s)/Q1(s)
+// That is, we use rational approximation to approximate
+// erf(1+s) - (c = (single)0.84506291151)
+// Note that |P1/Q1|< 0.078 for x in [0.84375,1.25]
+// where
+// P1(s) = degree 6 poly in s
+// Q1(s) = degree 6 poly in s
+//
+// 3. For x in [1.25,1/0.35(~2.857143)],
+// erfc(x) = (1/x)*exp(-x*x-0.5625+R1/S1)
+// erf(x) = 1 - erfc(x)
+// where
+// R1(z) = degree 7 poly in z, (z=1/x**2)
+// S1(z) = degree 8 poly in z
+//
+// 4. For x in [1/0.35,28]
+// erfc(x) = (1/x)*exp(-x*x-0.5625+R2/S2) if x > 0
+// = 2.0 - (1/x)*exp(-x*x-0.5625+R2/S2) if -6 x >= 28
+// erf(x) = sign(x) *(1 - tiny) (raise inexact)
+// erfc(x) = tiny*tiny (raise underflow) if x > 0
+// = 2 - tiny if x<0
+//
+// 7. Special case:
+// erf(0) = 0, erf(inf) = 1, erf(-inf) = -1,
+// erfc(0) = 1, erfc(inf) = 0, erfc(-inf) = 2,
+// erfc/erf(NaN) is NaN
+
+const (
+ erx = 8.45062911510467529297e-01 // 0x3FEB0AC160000000
+ // Coefficients for approximation to erf in [0, 0.84375]
+ efx = 1.28379167095512586316e-01 // 0x3FC06EBA8214DB69
+ efx8 = 1.02703333676410069053e+00 // 0x3FF06EBA8214DB69
+ pp0 = 1.28379167095512558561e-01 // 0x3FC06EBA8214DB68
+ pp1 = -3.25042107247001499370e-01 // 0xBFD4CD7D691CB913
+ pp2 = -2.84817495755985104766e-02 // 0xBF9D2A51DBD7194F
+ pp3 = -5.77027029648944159157e-03 // 0xBF77A291236668E4
+ pp4 = -2.37630166566501626084e-05 // 0xBEF8EAD6120016AC
+ qq1 = 3.97917223959155352819e-01 // 0x3FD97779CDDADC09
+ qq2 = 6.50222499887672944485e-02 // 0x3FB0A54C5536CEBA
+ qq3 = 5.08130628187576562776e-03 // 0x3F74D022C4D36B0F
+ qq4 = 1.32494738004321644526e-04 // 0x3F215DC9221C1A10
+ qq5 = -3.96022827877536812320e-06 // 0xBED09C4342A26120
+ // Coefficients for approximation to erf in [0.84375, 1.25]
+ pa0 = -2.36211856075265944077e-03 // 0xBF6359B8BEF77538
+ pa1 = 4.14856118683748331666e-01 // 0x3FDA8D00AD92B34D
+ pa2 = -3.72207876035701323847e-01 // 0xBFD7D240FBB8C3F1
+ pa3 = 3.18346619901161753674e-01 // 0x3FD45FCA805120E4
+ pa4 = -1.10894694282396677476e-01 // 0xBFBC63983D3E28EC
+ pa5 = 3.54783043256182359371e-02 // 0x3FA22A36599795EB
+ pa6 = -2.16637559486879084300e-03 // 0xBF61BF380A96073F
+ qa1 = 1.06420880400844228286e-01 // 0x3FBB3E6618EEE323
+ qa2 = 5.40397917702171048937e-01 // 0x3FE14AF092EB6F33
+ qa3 = 7.18286544141962662868e-02 // 0x3FB2635CD99FE9A7
+ qa4 = 1.26171219808761642112e-01 // 0x3FC02660E763351F
+ qa5 = 1.36370839120290507362e-02 // 0x3F8BEDC26B51DD1C
+ qa6 = 1.19844998467991074170e-02 // 0x3F888B545735151D
+ // Coefficients for approximation to erfc in [1.25, 1/0.35]
+ ra0 = -9.86494403484714822705e-03 // 0xBF843412600D6435
+ ra1 = -6.93858572707181764372e-01 // 0xBFE63416E4BA7360
+ ra2 = -1.05586262253232909814e+01 // 0xC0251E0441B0E726
+ ra3 = -6.23753324503260060396e+01 // 0xC04F300AE4CBA38D
+ ra4 = -1.62396669462573470355e+02 // 0xC0644CB184282266
+ ra5 = -1.84605092906711035994e+02 // 0xC067135CEBCCABB2
+ ra6 = -8.12874355063065934246e+01 // 0xC054526557E4D2F2
+ ra7 = -9.81432934416914548592e+00 // 0xC023A0EFC69AC25C
+ sa1 = 1.96512716674392571292e+01 // 0x4033A6B9BD707687
+ sa2 = 1.37657754143519042600e+02 // 0x4061350C526AE721
+ sa3 = 4.34565877475229228821e+02 // 0x407B290DD58A1A71
+ sa4 = 6.45387271733267880336e+02 // 0x40842B1921EC2868
+ sa5 = 4.29008140027567833386e+02 // 0x407AD02157700314
+ sa6 = 1.08635005541779435134e+02 // 0x405B28A3EE48AE2C
+ sa7 = 6.57024977031928170135e+00 // 0x401A47EF8E484A93
+ sa8 = -6.04244152148580987438e-02 // 0xBFAEEFF2EE749A62
+ // Coefficients for approximation to erfc in [1/.35, 28]
+ rb0 = -9.86494292470009928597e-03 // 0xBF84341239E86F4A
+ rb1 = -7.99283237680523006574e-01 // 0xBFE993BA70C285DE
+ rb2 = -1.77579549177547519889e+01 // 0xC031C209555F995A
+ rb3 = -1.60636384855821916062e+02 // 0xC064145D43C5ED98
+ rb4 = -6.37566443368389627722e+02 // 0xC083EC881375F228
+ rb5 = -1.02509513161107724954e+03 // 0xC09004616A2E5992
+ rb6 = -4.83519191608651397019e+02 // 0xC07E384E9BDC383F
+ sb1 = 3.03380607434824582924e+01 // 0x403E568B261D5190
+ sb2 = 3.25792512996573918826e+02 // 0x40745CAE221B9F0A
+ sb3 = 1.53672958608443695994e+03 // 0x409802EB189D5118
+ sb4 = 3.19985821950859553908e+03 // 0x40A8FFB7688C246A
+ sb5 = 2.55305040643316442583e+03 // 0x40A3F219CEDF3BE6
+ sb6 = 4.74528541206955367215e+02 // 0x407DA874E79FE763
+ sb7 = -2.24409524465858183362e+01 // 0xC03670E242712D62
+)
+
+// Erf returns the error function of x.
+//
+// Special cases are:
+//
+// Erf(+Inf) = 1
+// Erf(-Inf) = -1
+// Erf(NaN) = NaN
+func Erf(x float64) float64 {
+ if haveArchErf {
+ return archErf(x)
+ }
+ return erf(x)
+}
+
+func erf(x float64) float64 {
+ const (
+ VeryTiny = 2.848094538889218e-306 // 0x0080000000000000
+ Small = 1.0 / (1 << 28) // 2**-28
+ )
+ // special cases
+ switch {
+ case IsNaN(x):
+ return NaN()
+ case IsInf(x, 1):
+ return 1
+ case IsInf(x, -1):
+ return -1
+ }
+ sign := false
+ if x < 0 {
+ x = -x
+ sign = true
+ }
+ if x < 0.84375 { // |x| < 0.84375
+ var temp float64
+ if x < Small { // |x| < 2**-28
+ if x < VeryTiny {
+ temp = 0.125 * (8.0*x + efx8*x) // avoid underflow
+ } else {
+ temp = x + efx*x
+ }
+ } else {
+ z := x * x
+ r := pp0 + z*(pp1+z*(pp2+z*(pp3+z*pp4)))
+ s := 1 + z*(qq1+z*(qq2+z*(qq3+z*(qq4+z*qq5))))
+ y := r / s
+ temp = x + x*y
+ }
+ if sign {
+ return -temp
+ }
+ return temp
+ }
+ if x < 1.25 { // 0.84375 <= |x| < 1.25
+ s := x - 1
+ P := pa0 + s*(pa1+s*(pa2+s*(pa3+s*(pa4+s*(pa5+s*pa6)))))
+ Q := 1 + s*(qa1+s*(qa2+s*(qa3+s*(qa4+s*(qa5+s*qa6)))))
+ if sign {
+ return -erx - P/Q
+ }
+ return erx + P/Q
+ }
+ if x >= 6 { // inf > |x| >= 6
+ if sign {
+ return -1
+ }
+ return 1
+ }
+ s := 1 / (x * x)
+ var R, S float64
+ if x < 1/0.35 { // |x| < 1 / 0.35 ~ 2.857143
+ R = ra0 + s*(ra1+s*(ra2+s*(ra3+s*(ra4+s*(ra5+s*(ra6+s*ra7))))))
+ S = 1 + s*(sa1+s*(sa2+s*(sa3+s*(sa4+s*(sa5+s*(sa6+s*(sa7+s*sa8)))))))
+ } else { // |x| >= 1 / 0.35 ~ 2.857143
+ R = rb0 + s*(rb1+s*(rb2+s*(rb3+s*(rb4+s*(rb5+s*rb6)))))
+ S = 1 + s*(sb1+s*(sb2+s*(sb3+s*(sb4+s*(sb5+s*(sb6+s*sb7))))))
+ }
+ z := Float64frombits(Float64bits(x) & 0xffffffff00000000) // pseudo-single (20-bit) precision x
+ r := Exp(-z*z-0.5625) * Exp((z-x)*(z+x)+R/S)
+ if sign {
+ return r/x - 1
+ }
+ return 1 - r/x
+}
+
+// Erfc returns the complementary error function of x.
+//
+// Special cases are:
+//
+// Erfc(+Inf) = 0
+// Erfc(-Inf) = 2
+// Erfc(NaN) = NaN
+func Erfc(x float64) float64 {
+ if haveArchErfc {
+ return archErfc(x)
+ }
+ return erfc(x)
+}
+
+func erfc(x float64) float64 {
+ const Tiny = 1.0 / (1 << 56) // 2**-56
+ // special cases
+ switch {
+ case IsNaN(x):
+ return NaN()
+ case IsInf(x, 1):
+ return 0
+ case IsInf(x, -1):
+ return 2
+ }
+ sign := false
+ if x < 0 {
+ x = -x
+ sign = true
+ }
+ if x < 0.84375 { // |x| < 0.84375
+ var temp float64
+ if x < Tiny { // |x| < 2**-56
+ temp = x
+ } else {
+ z := x * x
+ r := pp0 + z*(pp1+z*(pp2+z*(pp3+z*pp4)))
+ s := 1 + z*(qq1+z*(qq2+z*(qq3+z*(qq4+z*qq5))))
+ y := r / s
+ if x < 0.25 { // |x| < 1/4
+ temp = x + x*y
+ } else {
+ temp = 0.5 + (x*y + (x - 0.5))
+ }
+ }
+ if sign {
+ return 1 + temp
+ }
+ return 1 - temp
+ }
+ if x < 1.25 { // 0.84375 <= |x| < 1.25
+ s := x - 1
+ P := pa0 + s*(pa1+s*(pa2+s*(pa3+s*(pa4+s*(pa5+s*pa6)))))
+ Q := 1 + s*(qa1+s*(qa2+s*(qa3+s*(qa4+s*(qa5+s*qa6)))))
+ if sign {
+ return 1 + erx + P/Q
+ }
+ return 1 - erx - P/Q
+
+ }
+ if x < 28 { // |x| < 28
+ s := 1 / (x * x)
+ var R, S float64
+ if x < 1/0.35 { // |x| < 1 / 0.35 ~ 2.857143
+ R = ra0 + s*(ra1+s*(ra2+s*(ra3+s*(ra4+s*(ra5+s*(ra6+s*ra7))))))
+ S = 1 + s*(sa1+s*(sa2+s*(sa3+s*(sa4+s*(sa5+s*(sa6+s*(sa7+s*sa8)))))))
+ } else { // |x| >= 1 / 0.35 ~ 2.857143
+ if sign && x > 6 {
+ return 2 // x < -6
+ }
+ R = rb0 + s*(rb1+s*(rb2+s*(rb3+s*(rb4+s*(rb5+s*rb6)))))
+ S = 1 + s*(sb1+s*(sb2+s*(sb3+s*(sb4+s*(sb5+s*(sb6+s*sb7))))))
+ }
+ z := Float64frombits(Float64bits(x) & 0xffffffff00000000) // pseudo-single (20-bit) precision x
+ r := Exp(-z*z-0.5625) * Exp((z-x)*(z+x)+R/S)
+ if sign {
+ return 2 - r/x
+ }
+ return r / x
+ }
+ if sign {
+ return 2
+ }
+ return 0
+}
diff --git a/go/src/math/erf_s390x.s b/go/src/math/erf_s390x.s
new file mode 100644
index 0000000000000000000000000000000000000000..99ab436e0945147eb19fe8f444abe58ddea4eecf
--- /dev/null
+++ b/go/src/math/erf_s390x.s
@@ -0,0 +1,293 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// Minimax polynomial coefficients and other constants
+DATA ·erfrodataL13<> + 0(SB)/8, $0.243673229298474689E+01
+DATA ·erfrodataL13<> + 8(SB)/8, $-.654905018503145600E+00
+DATA ·erfrodataL13<> + 16(SB)/8, $0.404669310217538718E+01
+DATA ·erfrodataL13<> + 24(SB)/8, $-.564189219162765367E+00
+DATA ·erfrodataL13<> + 32(SB)/8, $-.200104300906596851E+01
+DATA ·erfrodataL13<> + 40(SB)/8, $0.5
+DATA ·erfrodataL13<> + 48(SB)/8, $0.144070097650207154E+00
+DATA ·erfrodataL13<> + 56(SB)/8, $-.116697735205906191E+00
+DATA ·erfrodataL13<> + 64(SB)/8, $0.256847684882319665E-01
+DATA ·erfrodataL13<> + 72(SB)/8, $-.510805169106229148E-02
+DATA ·erfrodataL13<> + 80(SB)/8, $0.885258164825590267E-03
+DATA ·erfrodataL13<> + 88(SB)/8, $-.133861989591931411E-03
+DATA ·erfrodataL13<> + 96(SB)/8, $0.178294867340272534E-04
+DATA ·erfrodataL13<> + 104(SB)/8, $-.211436095674019218E-05
+DATA ·erfrodataL13<> + 112(SB)/8, $0.225503753499344434E-06
+DATA ·erfrodataL13<> + 120(SB)/8, $-.218247939190783624E-07
+DATA ·erfrodataL13<> + 128(SB)/8, $0.193179206264594029E-08
+DATA ·erfrodataL13<> + 136(SB)/8, $-.157440643541715319E-09
+DATA ·erfrodataL13<> + 144(SB)/8, $0.118878583237342616E-10
+DATA ·erfrodataL13<> + 152(SB)/8, $0.554289288424588473E-13
+DATA ·erfrodataL13<> + 160(SB)/8, $-.277649758489502214E-14
+DATA ·erfrodataL13<> + 168(SB)/8, $-.839318416990049443E-12
+DATA ·erfrodataL13<> + 176(SB)/8, $-2.25
+DATA ·erfrodataL13<> + 184(SB)/8, $.12837916709551258632
+DATA ·erfrodataL13<> + 192(SB)/8, $1.0
+DATA ·erfrodataL13<> + 200(SB)/8, $0.500000000000004237e+00
+DATA ·erfrodataL13<> + 208(SB)/8, $1.0
+DATA ·erfrodataL13<> + 216(SB)/8, $0.416666664838056960e-01
+DATA ·erfrodataL13<> + 224(SB)/8, $0.166666666630345592e+00
+DATA ·erfrodataL13<> + 232(SB)/8, $0.138926439368309441e-02
+DATA ·erfrodataL13<> + 240(SB)/8, $0.833349307718286047e-02
+DATA ·erfrodataL13<> + 248(SB)/8, $-.693147180559945286e+00
+DATA ·erfrodataL13<> + 256(SB)/8, $-.144269504088896339e+01
+DATA ·erfrodataL13<> + 264(SB)/8, $281475245147134.9375
+DATA ·erfrodataL13<> + 272(SB)/8, $0.358256136398192529E+01
+DATA ·erfrodataL13<> + 280(SB)/8, $-.554084396500738270E+00
+DATA ·erfrodataL13<> + 288(SB)/8, $0.203630123025312046E+02
+DATA ·erfrodataL13<> + 296(SB)/8, $-.735750304705934424E+01
+DATA ·erfrodataL13<> + 304(SB)/8, $0.250491598091071797E+02
+DATA ·erfrodataL13<> + 312(SB)/8, $-.118955882760959931E+02
+DATA ·erfrodataL13<> + 320(SB)/8, $0.942903335085524187E+01
+DATA ·erfrodataL13<> + 328(SB)/8, $-.564189522219085689E+00
+DATA ·erfrodataL13<> + 336(SB)/8, $-.503767199403555540E+01
+DATA ·erfrodataL13<> + 344(SB)/8, $0xbbc79ca10c924223
+DATA ·erfrodataL13<> + 352(SB)/8, $0.004099975562609307E+01
+DATA ·erfrodataL13<> + 360(SB)/8, $-.324434353381296556E+00
+DATA ·erfrodataL13<> + 368(SB)/8, $0.945204812084476250E-01
+DATA ·erfrodataL13<> + 376(SB)/8, $-.221407443830058214E-01
+DATA ·erfrodataL13<> + 384(SB)/8, $0.426072376238804349E-02
+DATA ·erfrodataL13<> + 392(SB)/8, $-.692229229127016977E-03
+DATA ·erfrodataL13<> + 400(SB)/8, $0.971111253652087188E-04
+DATA ·erfrodataL13<> + 408(SB)/8, $-.119752226272050504E-04
+DATA ·erfrodataL13<> + 416(SB)/8, $0.131662993588532278E-05
+DATA ·erfrodataL13<> + 424(SB)/8, $0.115776482315851236E-07
+DATA ·erfrodataL13<> + 432(SB)/8, $-.780118522218151687E-09
+DATA ·erfrodataL13<> + 440(SB)/8, $-.130465975877241088E-06
+DATA ·erfrodataL13<> + 448(SB)/8, $-0.25
+GLOBL ·erfrodataL13<> + 0(SB), RODATA, $456
+
+// Table of log correction terms
+DATA ·erftab2066<> + 0(SB)/8, $0.442737824274138381e-01
+DATA ·erftab2066<> + 8(SB)/8, $0.263602189790660309e-01
+DATA ·erftab2066<> + 16(SB)/8, $0.122565642281703586e-01
+DATA ·erftab2066<> + 24(SB)/8, $0.143757052860721398e-02
+DATA ·erftab2066<> + 32(SB)/8, $-.651375034121276075e-02
+DATA ·erftab2066<> + 40(SB)/8, $-.119317678849450159e-01
+DATA ·erftab2066<> + 48(SB)/8, $-.150868749549871069e-01
+DATA ·erftab2066<> + 56(SB)/8, $-.161992609578469234e-01
+DATA ·erftab2066<> + 64(SB)/8, $-.154492360403337917e-01
+DATA ·erftab2066<> + 72(SB)/8, $-.129850717389178721e-01
+DATA ·erftab2066<> + 80(SB)/8, $-.892902649276657891e-02
+DATA ·erftab2066<> + 88(SB)/8, $-.338202636596794887e-02
+DATA ·erftab2066<> + 96(SB)/8, $0.357266307045684762e-02
+DATA ·erftab2066<> + 104(SB)/8, $0.118665304327406698e-01
+DATA ·erftab2066<> + 112(SB)/8, $0.214434994118118914e-01
+DATA ·erftab2066<> + 120(SB)/8, $0.322580645161290314e-01
+GLOBL ·erftab2066<> + 0(SB), RODATA, $128
+
+// Table of +/- 1.0
+DATA ·erftab12067<> + 0(SB)/8, $1.0
+DATA ·erftab12067<> + 8(SB)/8, $-1.0
+GLOBL ·erftab12067<> + 0(SB), RODATA, $16
+
+// Erf returns the error function of the argument.
+//
+// Special cases are:
+// Erf(+Inf) = 1
+// Erf(-Inf) = -1
+// Erf(NaN) = NaN
+// The algorithm used is minimax polynomial approximation
+// with coefficients determined with a Remez exchange algorithm.
+
+TEXT ·erfAsm(SB), NOSPLIT, $0-16
+ FMOVD x+0(FP), F0
+ MOVD $·erfrodataL13<>+0(SB), R5
+ LGDR F0, R1
+ FMOVD F0, F6
+ SRAD $48, R1
+ MOVH $16383, R3
+ RISBGZ $49, $63, $0, R1, R2
+ MOVW R2, R6
+ MOVW R3, R7
+ CMPBGT R6, R7, L2
+ MOVH $12287, R1
+ MOVW R1, R7
+ CMPBLE R6, R7 ,L12
+ MOVH $16367, R1
+ MOVW R1, R7
+ CMPBGT R6, R7, L5
+ FMOVD 448(R5), F4
+ FMADD F0, F0, F4
+ FMOVD 440(R5), F3
+ WFMDB V4, V4, V2
+ FMOVD 432(R5), F0
+ FMOVD 424(R5), F1
+ WFMADB V2, V0, V3, V0
+ FMOVD 416(R5), F3
+ WFMADB V2, V1, V3, V1
+ FMOVD 408(R5), F5
+ FMOVD 400(R5), F3
+ WFMADB V2, V0, V5, V0
+ WFMADB V2, V1, V3, V1
+ FMOVD 392(R5), F5
+ FMOVD 384(R5), F3
+ WFMADB V2, V0, V5, V0
+ WFMADB V2, V1, V3, V1
+ FMOVD 376(R5), F5
+ FMOVD 368(R5), F3
+ WFMADB V2, V0, V5, V0
+ WFMADB V2, V1, V3, V1
+ FMOVD 360(R5), F5
+ FMOVD 352(R5), F3
+ WFMADB V2, V0, V5, V0
+ WFMADB V2, V1, V3, V2
+ WFMADB V4, V0, V2, V0
+ WFMADB V6, V0, V6, V0
+L1:
+ FMOVD F0, ret+8(FP)
+ RET
+L2:
+ MOVH R1, R1
+ MOVH $16407, R3
+ SRW $31, R1, R1
+ MOVW R2, R6
+ MOVW R3, R7
+ CMPBLE R6, R7, L6
+ MOVW R1, R1
+ SLD $3, R1, R1
+ MOVD $·erftab12067<>+0(SB), R3
+ WORD $0x68013000 //ld %f0,0(%r1,%r3)
+ MOVH $32751, R1
+ MOVW R1, R7
+ CMPBGT R6, R7, L7
+ FMOVD 344(R5), F2
+ FMADD F2, F0, F0
+L7:
+ WFCEDBS V6, V6, V2
+ BEQ L1
+ FMOVD F6, F0
+ FMOVD F0, ret+8(FP)
+ RET
+
+L6:
+ MOVW R1, R1
+ SLD $3, R1, R1
+ MOVD $·erftab12067<>+0(SB), R4
+ WFMDB V0, V0, V1
+ MOVH $0x0, R3
+ WORD $0x68014000 //ld %f0,0(%r1,%r4)
+ MOVH $16399, R1
+ MOVW R2, R6
+ MOVW R1, R7
+ CMPBGT R6, R7, L8
+ FMOVD 336(R5), F3
+ FMOVD 328(R5), F2
+ FMOVD F1, F4
+ WFMADB V1, V2, V3, V2
+ WORD $0xED405140 //adb %f4,.L30-.L13(%r5)
+ BYTE $0x00
+ BYTE $0x1A
+ FMOVD 312(R5), F3
+ WFMADB V1, V2, V3, V2
+ FMOVD 304(R5), F3
+ WFMADB V1, V4, V3, V4
+ FMOVD 296(R5), F3
+ WFMADB V1, V2, V3, V2
+ FMOVD 288(R5), F3
+ WFMADB V1, V4, V3, V4
+ FMOVD 280(R5), F3
+ WFMADB V1, V2, V3, V2
+ FMOVD 272(R5), F3
+ WFMADB V1, V4, V3, V4
+L9:
+ FMOVD 264(R5), F3
+ FMUL F4, F6
+ FMOVD 256(R5), F4
+ WFMADB V1, V4, V3, V4
+ FDIV F6, F2
+ LGDR F4, R1
+ FSUB F3, F4
+ FMOVD 248(R5), F6
+ WFMSDB V4, V6, V1, V4
+ FMOVD 240(R5), F1
+ FMOVD 232(R5), F6
+ WFMADB V4, V6, V1, V6
+ FMOVD 224(R5), F1
+ FMOVD 216(R5), F3
+ WFMADB V4, V3, V1, V3
+ WFMDB V4, V4, V1
+ FMOVD 208(R5), F5
+ WFMADB V6, V1, V3, V6
+ FMOVD 200(R5), F3
+ MOVH R1,R1
+ WFMADB V4, V3, V5, V3
+ RISBGZ $57, $60, $3, R1, R2
+ WFMADB V1, V6, V3, V6
+ RISBGN $0, $15, $48, R1, R3
+ MOVD $·erftab2066<>+0(SB), R1
+ FMOVD 192(R5), F1
+ LDGR R3, F3
+ WORD $0xED221000 //madb %f2,%f2,0(%r2,%r1)
+ BYTE $0x20
+ BYTE $0x1E
+ WFMADB V4, V6, V1, V4
+ FMUL F3, F2
+ FMADD F4, F2, F0
+ FMOVD F0, ret+8(FP)
+ RET
+L12:
+ FMOVD 184(R5), F0
+ WFMADB V6, V0, V6, V0
+ FMOVD F0, ret+8(FP)
+ RET
+L5:
+ FMOVD 176(R5), F1
+ FMADD F0, F0, F1
+ FMOVD 168(R5), F3
+ WFMDB V1, V1, V2
+ FMOVD 160(R5), F0
+ FMOVD 152(R5), F4
+ WFMADB V2, V0, V3, V0
+ FMOVD 144(R5), F3
+ WFMADB V2, V4, V3, V4
+ FMOVD 136(R5), F5
+ FMOVD 128(R5), F3
+ WFMADB V2, V0, V5, V0
+ WFMADB V2, V4, V3, V4
+ FMOVD 120(R5), F5
+ FMOVD 112(R5), F3
+ WFMADB V2, V0, V5, V0
+ WFMADB V2, V4, V3, V4
+ FMOVD 104(R5), F5
+ FMOVD 96(R5), F3
+ WFMADB V2, V0, V5, V0
+ WFMADB V2, V4, V3, V4
+ FMOVD 88(R5), F5
+ FMOVD 80(R5), F3
+ WFMADB V2, V0, V5, V0
+ WFMADB V2, V4, V3, V4
+ FMOVD 72(R5), F5
+ FMOVD 64(R5), F3
+ WFMADB V2, V0, V5, V0
+ WFMADB V2, V4, V3, V4
+ FMOVD 56(R5), F5
+ FMOVD 48(R5), F3
+ WFMADB V2, V0, V5, V0
+ WFMADB V2, V4, V3, V2
+ FMOVD 40(R5), F4
+ WFMADB V1, V0, V2, V0
+ FMUL F6, F0
+ FMADD F4, F6, F0
+ FMOVD F0, ret+8(FP)
+ RET
+L8:
+ FMOVD 32(R5), F3
+ FMOVD 24(R5), F2
+ FMOVD F1, F4
+ WFMADB V1, V2, V3, V2
+ WORD $0xED405010 //adb %f4,.L68-.L13(%r5)
+ BYTE $0x00
+ BYTE $0x1A
+ FMOVD 8(R5), F3
+ WFMADB V1, V2, V3, V2
+ FMOVD ·erfrodataL13<>+0(SB), F3
+ WFMADB V1, V4, V3, V4
+ BR L9
diff --git a/go/src/math/erfc_s390x.s b/go/src/math/erfc_s390x.s
new file mode 100644
index 0000000000000000000000000000000000000000..e03a7749ff290cafe58fea0d15eca0b0ebeadb81
--- /dev/null
+++ b/go/src/math/erfc_s390x.s
@@ -0,0 +1,527 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+#define Neg2p11 0xC000E147AE147AE1
+#define Pos15 0x402E
+
+// Minimax polynomial coefficients and other constants
+DATA ·erfcrodataL38<> + 0(SB)/8, $.234875460637085087E-01
+DATA ·erfcrodataL38<> + 8(SB)/8, $.234469449299256284E-01
+DATA ·erfcrodataL38<> + 16(SB)/8, $-.606918710392844955E-04
+DATA ·erfcrodataL38<> + 24(SB)/8, $-.198827088077636213E-04
+DATA ·erfcrodataL38<> + 32(SB)/8, $.257805645845475331E-06
+DATA ·erfcrodataL38<> + 40(SB)/8, $-.184427218110620284E-09
+DATA ·erfcrodataL38<> + 48(SB)/8, $.122408098288933181E-10
+DATA ·erfcrodataL38<> + 56(SB)/8, $.484691106751495392E-07
+DATA ·erfcrodataL38<> + 64(SB)/8, $-.150147637632890281E-08
+DATA ·erfcrodataL38<> + 72(SB)/8, $23.999999999973521625
+DATA ·erfcrodataL38<> + 80(SB)/8, $27.226017111108365754
+DATA ·erfcrodataL38<> + 88(SB)/8, $-2.0
+DATA ·erfcrodataL38<> + 96(SB)/8, $0.100108802034478228E+00
+DATA ·erfcrodataL38<> + 104(SB)/8, $0.244588413746558125E+00
+DATA ·erfcrodataL38<> + 112(SB)/8, $-.669188879646637174E-01
+DATA ·erfcrodataL38<> + 120(SB)/8, $0.151311447000953551E-01
+DATA ·erfcrodataL38<> + 128(SB)/8, $-.284720833493302061E-02
+DATA ·erfcrodataL38<> + 136(SB)/8, $0.455491239358743212E-03
+DATA ·erfcrodataL38<> + 144(SB)/8, $-.631850539280720949E-04
+DATA ·erfcrodataL38<> + 152(SB)/8, $0.772532660726086679E-05
+DATA ·erfcrodataL38<> + 160(SB)/8, $-.843706007150936940E-06
+DATA ·erfcrodataL38<> + 168(SB)/8, $-.735330214904227472E-08
+DATA ·erfcrodataL38<> + 176(SB)/8, $0.753002008837084967E-09
+DATA ·erfcrodataL38<> + 184(SB)/8, $0.832482036660624637E-07
+DATA ·erfcrodataL38<> + 192(SB)/8, $-0.75
+DATA ·erfcrodataL38<> + 200(SB)/8, $.927765678007128609E-01
+DATA ·erfcrodataL38<> + 208(SB)/8, $.903621209344751506E-01
+DATA ·erfcrodataL38<> + 216(SB)/8, $-.344203375025257265E-02
+DATA ·erfcrodataL38<> + 224(SB)/8, $-.869243428221791329E-03
+DATA ·erfcrodataL38<> + 232(SB)/8, $.174699813107105603E-03
+DATA ·erfcrodataL38<> + 240(SB)/8, $.649481036316130000E-05
+DATA ·erfcrodataL38<> + 248(SB)/8, $-.895265844897118382E-05
+DATA ·erfcrodataL38<> + 256(SB)/8, $.135970046909529513E-05
+DATA ·erfcrodataL38<> + 264(SB)/8, $.277617717014748015E-06
+DATA ·erfcrodataL38<> + 272(SB)/8, $.810628018408232910E-08
+DATA ·erfcrodataL38<> + 280(SB)/8, $.210430084693497985E-07
+DATA ·erfcrodataL38<> + 288(SB)/8, $-.342138077525615091E-08
+DATA ·erfcrodataL38<> + 296(SB)/8, $-.165467946798610800E-06
+DATA ·erfcrodataL38<> + 304(SB)/8, $5.999999999988412824
+DATA ·erfcrodataL38<> + 312(SB)/8, $.468542210149072159E-01
+DATA ·erfcrodataL38<> + 320(SB)/8, $.465343528567604256E-01
+DATA ·erfcrodataL38<> + 328(SB)/8, $-.473338083650201733E-03
+DATA ·erfcrodataL38<> + 336(SB)/8, $-.147220659069079156E-03
+DATA ·erfcrodataL38<> + 344(SB)/8, $.755284723554388339E-05
+DATA ·erfcrodataL38<> + 352(SB)/8, $.116158570631428789E-05
+DATA ·erfcrodataL38<> + 360(SB)/8, $-.155445501551602389E-06
+DATA ·erfcrodataL38<> + 368(SB)/8, $-.616940119847805046E-10
+DATA ·erfcrodataL38<> + 376(SB)/8, $-.728705590727563158E-10
+DATA ·erfcrodataL38<> + 384(SB)/8, $-.983452460354586779E-08
+DATA ·erfcrodataL38<> + 392(SB)/8, $.365156164194346316E-08
+DATA ·erfcrodataL38<> + 400(SB)/8, $11.999999999996530775
+DATA ·erfcrodataL38<> + 408(SB)/8, $0.467773498104726584E-02
+DATA ·erfcrodataL38<> + 416(SB)/8, $0.206669853540920535E-01
+DATA ·erfcrodataL38<> + 424(SB)/8, $0.413339707081841473E-01
+DATA ·erfcrodataL38<> + 432(SB)/8, $0.482229658262131320E-01
+DATA ·erfcrodataL38<> + 440(SB)/8, $0.344449755901841897E-01
+DATA ·erfcrodataL38<> + 448(SB)/8, $0.130890907240765465E-01
+DATA ·erfcrodataL38<> + 456(SB)/8, $-.459266344100642687E-03
+DATA ·erfcrodataL38<> + 464(SB)/8, $-.337888800856913728E-02
+DATA ·erfcrodataL38<> + 472(SB)/8, $-.159103061687062373E-02
+DATA ·erfcrodataL38<> + 480(SB)/8, $-.501128905515922644E-04
+DATA ·erfcrodataL38<> + 488(SB)/8, $0.262775855852903132E-03
+DATA ·erfcrodataL38<> + 496(SB)/8, $0.103860982197462436E-03
+DATA ·erfcrodataL38<> + 504(SB)/8, $-.548835785414200775E-05
+DATA ·erfcrodataL38<> + 512(SB)/8, $-.157075054646618214E-04
+DATA ·erfcrodataL38<> + 520(SB)/8, $-.480056366276045110E-05
+DATA ·erfcrodataL38<> + 528(SB)/8, $0.198263013759701555E-05
+DATA ·erfcrodataL38<> + 536(SB)/8, $-.224394262958888780E-06
+DATA ·erfcrodataL38<> + 544(SB)/8, $-.321853693146683428E-06
+DATA ·erfcrodataL38<> + 552(SB)/8, $0.445073894984683537E-07
+DATA ·erfcrodataL38<> + 560(SB)/8, $0.660425940000555729E-06
+DATA ·erfcrodataL38<> + 568(SB)/8, $2.0
+DATA ·erfcrodataL38<> + 576(SB)/8, $8.63616855509444462538e-78
+DATA ·erfcrodataL38<> + 584(SB)/8, $1.00000000000000222044
+DATA ·erfcrodataL38<> + 592(SB)/8, $0.500000000000004237e+00
+DATA ·erfcrodataL38<> + 600(SB)/8, $0.416666664838056960e-01
+DATA ·erfcrodataL38<> + 608(SB)/8, $0.166666666630345592e+00
+DATA ·erfcrodataL38<> + 616(SB)/8, $0.138926439368309441e-02
+DATA ·erfcrodataL38<> + 624(SB)/8, $0.833349307718286047e-02
+DATA ·erfcrodataL38<> + 632(SB)/8, $-.693147180558298714e+00
+DATA ·erfcrodataL38<> + 640(SB)/8, $-.164659495826017651e-11
+DATA ·erfcrodataL38<> + 648(SB)/8, $.179001151181866548E+00
+DATA ·erfcrodataL38<> + 656(SB)/8, $-.144269504088896339e+01
+DATA ·erfcrodataL38<> + 664(SB)/8, $+281475245147134.9375
+DATA ·erfcrodataL38<> + 672(SB)/8, $.163116780021877404E+00
+DATA ·erfcrodataL38<> + 680(SB)/8, $-.201574395828120710E-01
+DATA ·erfcrodataL38<> + 688(SB)/8, $-.185726336009394125E-02
+DATA ·erfcrodataL38<> + 696(SB)/8, $.199349204957273749E-02
+DATA ·erfcrodataL38<> + 704(SB)/8, $-.554902415532606242E-03
+DATA ·erfcrodataL38<> + 712(SB)/8, $-.638914789660242846E-05
+DATA ·erfcrodataL38<> + 720(SB)/8, $-.424441522653742898E-04
+DATA ·erfcrodataL38<> + 728(SB)/8, $.827967511921486190E-04
+DATA ·erfcrodataL38<> + 736(SB)/8, $.913965446284062654E-05
+DATA ·erfcrodataL38<> + 744(SB)/8, $.277344791076320853E-05
+DATA ·erfcrodataL38<> + 752(SB)/8, $-.467239678927239526E-06
+DATA ·erfcrodataL38<> + 760(SB)/8, $.344814065920419986E-07
+DATA ·erfcrodataL38<> + 768(SB)/8, $-.366013491552527132E-05
+DATA ·erfcrodataL38<> + 776(SB)/8, $.181242810023783439E-05
+DATA ·erfcrodataL38<> + 784(SB)/8, $2.999999999991234567
+DATA ·erfcrodataL38<> + 792(SB)/8, $1.0
+GLOBL ·erfcrodataL38<> + 0(SB), RODATA, $800
+
+// Table of log correction terms
+DATA ·erfctab2069<> + 0(SB)/8, $0.442737824274138381e-01
+DATA ·erfctab2069<> + 8(SB)/8, $0.263602189790660309e-01
+DATA ·erfctab2069<> + 16(SB)/8, $0.122565642281703586e-01
+DATA ·erfctab2069<> + 24(SB)/8, $0.143757052860721398e-02
+DATA ·erfctab2069<> + 32(SB)/8, $-.651375034121276075e-02
+DATA ·erfctab2069<> + 40(SB)/8, $-.119317678849450159e-01
+DATA ·erfctab2069<> + 48(SB)/8, $-.150868749549871069e-01
+DATA ·erfctab2069<> + 56(SB)/8, $-.161992609578469234e-01
+DATA ·erfctab2069<> + 64(SB)/8, $-.154492360403337917e-01
+DATA ·erfctab2069<> + 72(SB)/8, $-.129850717389178721e-01
+DATA ·erfctab2069<> + 80(SB)/8, $-.892902649276657891e-02
+DATA ·erfctab2069<> + 88(SB)/8, $-.338202636596794887e-02
+DATA ·erfctab2069<> + 96(SB)/8, $0.357266307045684762e-02
+DATA ·erfctab2069<> + 104(SB)/8, $0.118665304327406698e-01
+DATA ·erfctab2069<> + 112(SB)/8, $0.214434994118118914e-01
+DATA ·erfctab2069<> + 120(SB)/8, $0.322580645161290314e-01
+GLOBL ·erfctab2069<> + 0(SB), RODATA, $128
+
+// Erfc returns the complementary error function of the argument.
+//
+// Special cases are:
+// Erfc(+Inf) = 0
+// Erfc(-Inf) = 2
+// Erfc(NaN) = NaN
+// The algorithm used is minimax polynomial approximation
+// with coefficients determined with a Remez exchange algorithm.
+// This assembly implementation handles inputs in the range [-2.11, +15].
+// For all other inputs we call the generic Go implementation.
+
+TEXT ·erfcAsm(SB), NOSPLIT|NOFRAME, $0-16
+ MOVD x+0(FP), R1
+ MOVD $Neg2p11, R2
+ CMPUBGT R1, R2, usego
+
+ FMOVD x+0(FP), F0
+ MOVD $·erfcrodataL38<>+0(SB), R9
+ FMOVD F0, F2
+ SRAD $48, R1
+ MOVH R1, R2
+ ANDW $0x7FFF, R1
+ MOVH $Pos15, R3
+ CMPW R1, R3
+ BGT usego
+ MOVH $0x3FFF, R3
+ MOVW R1, R6
+ MOVW R3, R7
+ CMPBGT R6, R7, L2
+ MOVH $0x3FEF, R3
+ MOVW R3, R7
+ CMPBGT R6, R7, L3
+ MOVH $0x2FFF, R2
+ MOVW R2, R7
+ CMPBGT R6, R7, L4
+ FMOVD 792(R9), F0
+ WFSDB V2, V0, V2
+ FMOVD F2, ret+8(FP)
+ RET
+
+L2:
+ LTDBR F0, F0
+ MOVH $0x0, R4
+ BLTU L3
+ FMOVD F0, F1
+L9:
+ MOVH $0x400F, R3
+ MOVW R1, R6
+ MOVW R3, R7
+ CMPBGT R6, R7, L10
+ FMOVD 784(R9), F3
+ FSUB F1, F3
+ VLEG $0, 776(R9), V20
+ WFDDB V1, V3, V6
+ VLEG $0, 768(R9), V18
+ FMOVD 760(R9), F7
+ FMOVD 752(R9), F5
+ VLEG $0, 744(R9), V16
+ FMOVD 736(R9), F3
+ FMOVD 728(R9), F2
+ FMOVD 720(R9), F4
+ WFMDB V6, V6, V1
+ FMUL F0, F0
+ MOVH $0x0, R3
+ WFMADB V1, V7, V20, V7
+ WFMADB V1, V5, V18, V5
+ WFMADB V1, V7, V16, V7
+ WFMADB V1, V5, V3, V5
+ WFMADB V1, V7, V4, V7
+ WFMADB V1, V5, V2, V5
+ FMOVD 712(R9), F2
+ WFMADB V1, V7, V2, V7
+ FMOVD 704(R9), F2
+ WFMADB V1, V5, V2, V5
+ FMOVD 696(R9), F2
+ WFMADB V1, V7, V2, V7
+ FMOVD 688(R9), F2
+ MOVH $0x0, R1
+ WFMADB V1, V5, V2, V5
+ FMOVD 680(R9), F2
+ WFMADB V1, V7, V2, V7
+ FMOVD 672(R9), F2
+ WFMADB V1, V5, V2, V1
+ FMOVD 664(R9), F3
+ WFMADB V6, V7, V1, V7
+ FMOVD 656(R9), F5
+ FMOVD 648(R9), F2
+ WFMADB V0, V5, V3, V5
+ WFMADB V6, V7, V2, V7
+L11:
+ LGDR F5, R6
+ WFSDB V0, V0, V2
+ WORD $0xED509298 //sdb %f5,.L55-.L38(%r9)
+ BYTE $0x00
+ BYTE $0x1B
+ FMOVD 640(R9), F6
+ FMOVD 632(R9), F4
+ WFMSDB V5, V6, V2, V6
+ WFMSDB V5, V4, V0, V4
+ FMOVD 624(R9), F2
+ FADD F6, F4
+ FMOVD 616(R9), F0
+ FMOVD 608(R9), F6
+ WFMADB V4, V0, V2, V0
+ FMOVD 600(R9), F3
+ WFMDB V4, V4, V2
+ MOVH R6,R6
+ ADD R6, R3
+ WFMADB V4, V3, V6, V3
+ FMOVD 592(R9), F6
+ WFMADB V0, V2, V3, V0
+ FMOVD 584(R9), F3
+ WFMADB V4, V6, V3, V6
+ RISBGZ $57, $60, $3, R3, R12
+ WFMADB V2, V0, V6, V0
+ MOVD $·erfctab2069<>+0(SB), R5
+ WORD $0x682C5000 //ld %f2,0(%r12,%r5)
+ FMADD F2, F4, F4
+ RISBGN $0, $15, $48, R3, R4
+ WFMADB V4, V0, V2, V4
+ LDGR R4, F2
+ FMADD F4, F2, F2
+ MOVW R2, R6
+ CMPBLE R6, $0, L20
+ MOVW R1, R6
+ CMPBEQ R6, $0, L21
+ WORD $0xED709240 //mdb %f7,.L66-.L38(%r9)
+ BYTE $0x00
+ BYTE $0x1C
+L21:
+ FMUL F7, F2
+L1:
+ FMOVD F2, ret+8(FP)
+ RET
+L3:
+ LTDBR F0, F0
+ BLTU L30
+ FMOVD 568(R9), F2
+ WFSDB V0, V2, V0
+L8:
+ WFMDB V0, V0, V4
+ FMOVD 560(R9), F2
+ FMOVD 552(R9), F6
+ FMOVD 544(R9), F1
+ WFMADB V4, V6, V2, V6
+ FMOVD 536(R9), F2
+ WFMADB V4, V1, V2, V1
+ FMOVD 528(R9), F3
+ FMOVD 520(R9), F2
+ WFMADB V4, V6, V3, V6
+ WFMADB V4, V1, V2, V1
+ FMOVD 512(R9), F3
+ FMOVD 504(R9), F2
+ WFMADB V4, V6, V3, V6
+ WFMADB V4, V1, V2, V1
+ FMOVD 496(R9), F3
+ FMOVD 488(R9), F2
+ WFMADB V4, V6, V3, V6
+ WFMADB V4, V1, V2, V1
+ FMOVD 480(R9), F3
+ FMOVD 472(R9), F2
+ WFMADB V4, V6, V3, V6
+ WFMADB V4, V1, V2, V1
+ FMOVD 464(R9), F3
+ FMOVD 456(R9), F2
+ WFMADB V4, V6, V3, V6
+ WFMADB V4, V1, V2, V1
+ FMOVD 448(R9), F3
+ FMOVD 440(R9), F2
+ WFMADB V4, V6, V3, V6
+ WFMADB V4, V1, V2, V1
+ FMOVD 432(R9), F3
+ FMOVD 424(R9), F2
+ WFMADB V4, V6, V3, V6
+ WFMADB V4, V1, V2, V1
+ FMOVD 416(R9), F3
+ FMOVD 408(R9), F2
+ WFMADB V4, V6, V3, V6
+ FMADD F1, F4, F2
+ FMADD F6, F0, F2
+ MOVW R2, R6
+ CMPBGE R6, $0, L1
+ FMOVD 568(R9), F0
+ WFSDB V2, V0, V2
+ BR L1
+L10:
+ MOVH $0x401F, R3
+ MOVW R1, R6
+ MOVW R3, R7
+ CMPBLE R6, R7, L36
+ MOVH $0x402F, R3
+ MOVW R3, R7
+ CMPBGT R6, R7, L13
+ FMOVD 400(R9), F3
+ FSUB F1, F3
+ VLEG $0, 392(R9), V20
+ WFDDB V1, V3, V6
+ VLEG $0, 384(R9), V18
+ FMOVD 376(R9), F2
+ FMOVD 368(R9), F4
+ VLEG $0, 360(R9), V16
+ FMOVD 352(R9), F7
+ FMOVD 344(R9), F3
+ FMUL F0, F0
+ WFMDB V6, V6, V1
+ FMOVD 656(R9), F5
+ MOVH $0x0, R3
+ WFMADB V1, V2, V20, V2
+ WFMADB V1, V4, V18, V4
+ WFMADB V1, V2, V16, V2
+ WFMADB V1, V4, V7, V4
+ WFMADB V1, V2, V3, V2
+ FMOVD 336(R9), F3
+ WFMADB V1, V4, V3, V4
+ FMOVD 328(R9), F3
+ WFMADB V1, V2, V3, V2
+ FMOVD 320(R9), F3
+ WFMADB V1, V4, V3, V1
+ FMOVD 312(R9), F7
+ WFMADB V6, V2, V1, V2
+ MOVH $0x0, R1
+ FMOVD 664(R9), F3
+ FMADD F2, F6, F7
+ WFMADB V0, V5, V3, V5
+ BR L11
+L35:
+ LCDBR F0, F1
+ BR L9
+L36:
+ FMOVD 304(R9), F3
+ FSUB F1, F3
+ VLEG $0, 296(R9), V20
+ WFDDB V1, V3, V6
+ FMOVD 288(R9), F5
+ FMOVD 280(R9), F1
+ FMOVD 272(R9), F2
+ VLEG $0, 264(R9), V18
+ VLEG $0, 256(R9), V16
+ FMOVD 248(R9), F3
+ FMOVD 240(R9), F4
+ WFMDB V6, V6, V7
+ FMUL F0, F0
+ MOVH $0x0, R3
+ FMADD F5, F7, F1
+ WFMADB V7, V2, V20, V2
+ WFMADB V7, V1, V18, V1
+ WFMADB V7, V2, V16, V2
+ WFMADB V7, V1, V3, V1
+ WFMADB V7, V2, V4, V2
+ FMOVD 232(R9), F4
+ WFMADB V7, V1, V4, V1
+ FMOVD 224(R9), F4
+ WFMADB V7, V2, V4, V2
+ FMOVD 216(R9), F4
+ WFMADB V7, V1, V4, V1
+ FMOVD 208(R9), F4
+ MOVH $0x0, R1
+ WFMADB V7, V2, V4, V7
+ FMOVD 656(R9), F5
+ WFMADB V6, V1, V7, V1
+ FMOVD 664(R9), F3
+ FMOVD 200(R9), F7
+ WFMADB V0, V5, V3, V5
+ FMADD F1, F6, F7
+ BR L11
+L4:
+ FMOVD 192(R9), F1
+ FMADD F0, F0, F1
+ FMOVD 184(R9), F3
+ WFMDB V1, V1, V0
+ FMOVD 176(R9), F4
+ FMOVD 168(R9), F6
+ WFMADB V0, V4, V3, V4
+ FMOVD 160(R9), F3
+ WFMADB V0, V6, V3, V6
+ FMOVD 152(R9), F5
+ FMOVD 144(R9), F3
+ WFMADB V0, V4, V5, V4
+ WFMADB V0, V6, V3, V6
+ FMOVD 136(R9), F5
+ FMOVD 128(R9), F3
+ WFMADB V0, V4, V5, V4
+ WFMADB V0, V6, V3, V6
+ FMOVD 120(R9), F5
+ FMOVD 112(R9), F3
+ WFMADB V0, V4, V5, V4
+ WFMADB V0, V6, V3, V6
+ FMOVD 104(R9), F5
+ FMOVD 96(R9), F3
+ WFMADB V0, V4, V5, V4
+ WFMADB V0, V6, V3, V0
+ FMOVD F2, F6
+ FMADD F4, F1, F0
+ WORD $0xED609318 //sdb %f6,.L39-.L38(%r9)
+ BYTE $0x00
+ BYTE $0x1B
+ WFMSDB V2, V0, V6, V2
+ FMOVD F2, ret+8(FP)
+ RET
+L30:
+ WORD $0xED009238 //adb %f0,.L67-.L38(%r9)
+ BYTE $0x00
+ BYTE $0x1A
+ BR L8
+L20:
+ FMOVD 88(R9), F0
+ WFMADB V7, V2, V0, V2
+ LCDBR F2, F2
+ FMOVD F2, ret+8(FP)
+ RET
+L13:
+ MOVH $0x403A, R3
+ MOVW R1, R6
+ MOVW R3, R7
+ CMPBLE R6, R7, L4
+ WORD $0xED109050 //cdb %f1,.L128-.L38(%r9)
+ BYTE $0x00
+ BYTE $0x19
+ BGE L37
+ BVS L37
+ FMOVD 72(R9), F6
+ FSUB F1, F6
+ MOVH $0x1000, R3
+ FDIV F1, F6
+ MOVH $0x1000, R1
+L17:
+ WFMDB V6, V6, V1
+ FMOVD 64(R9), F2
+ FMOVD 56(R9), F4
+ FMOVD 48(R9), F3
+ WFMADB V1, V3, V2, V3
+ FMOVD 40(R9), F2
+ WFMADB V1, V2, V4, V2
+ FMOVD 32(R9), F4
+ WFMADB V1, V3, V4, V3
+ FMOVD 24(R9), F4
+ WFMADB V1, V2, V4, V2
+ FMOVD 16(R9), F4
+ WFMADB V1, V3, V4, V3
+ FMOVD 8(R9), F4
+ WFMADB V1, V2, V4, V1
+ FMUL F0, F0
+ WFMADB V3, V6, V1, V3
+ FMOVD 656(R9), F5
+ FMOVD 664(R9), F4
+ FMOVD 0(R9), F7
+ WFMADB V0, V5, V4, V5
+ FMADD F6, F3, F7
+ BR L11
+L14:
+ FMOVD 72(R9), F6
+ FSUB F1, F6
+ MOVH $0x403A, R3
+ FDIV F1, F6
+ MOVW R1, R6
+ MOVW R3, R7
+ CMPBEQ R6, R7, L23
+ MOVH $0x0, R3
+ MOVH $0x0, R1
+ BR L17
+L37:
+ WFCEDBS V0, V0, V0
+ BVS L1
+ MOVW R2, R6
+ CMPBLE R6, $0, L18
+ MOVH $0x7FEF, R2
+ MOVW R1, R6
+ MOVW R2, R7
+ CMPBGT R6, R7, L24
+
+ WORD $0xA5400010 //iihh %r4,16
+ LDGR R4, F2
+ FMUL F2, F2
+ BR L1
+L23:
+ MOVH $0x1000, R3
+ MOVH $0x1000, R1
+ BR L17
+L24:
+ FMOVD $0, F2
+ BR L1
+L18:
+ MOVH $0x7FEF, R2
+ MOVW R1, R6
+ MOVW R2, R7
+ CMPBGT R6, R7, L25
+ WORD $0xA5408010 //iihh %r4,32784
+ FMOVD 568(R9), F2
+ LDGR R4, F0
+ FMADD F2, F0, F2
+ BR L1
+L25:
+ FMOVD 568(R9), F2
+ BR L1
+usego:
+ BR ·erfc(SB)
diff --git a/go/src/math/erfinv.go b/go/src/math/erfinv.go
new file mode 100644
index 0000000000000000000000000000000000000000..8e630f9736810e13cd32f8701fa38efb5cac3269
--- /dev/null
+++ b/go/src/math/erfinv.go
@@ -0,0 +1,129 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+ Inverse of the floating-point error function.
+*/
+
+// This implementation is based on the rational approximation
+// of percentage points of normal distribution available from
+// https://www.jstor.org/stable/2347330.
+
+const (
+ // Coefficients for approximation to erf in |x| <= 0.85
+ a0 = 1.1975323115670912564578e0
+ a1 = 4.7072688112383978012285e1
+ a2 = 6.9706266534389598238465e2
+ a3 = 4.8548868893843886794648e3
+ a4 = 1.6235862515167575384252e4
+ a5 = 2.3782041382114385731252e4
+ a6 = 1.1819493347062294404278e4
+ a7 = 8.8709406962545514830200e2
+ b0 = 1.0000000000000000000e0
+ b1 = 4.2313330701600911252e1
+ b2 = 6.8718700749205790830e2
+ b3 = 5.3941960214247511077e3
+ b4 = 2.1213794301586595867e4
+ b5 = 3.9307895800092710610e4
+ b6 = 2.8729085735721942674e4
+ b7 = 5.2264952788528545610e3
+ // Coefficients for approximation to erf in 0.85 < |x| <= 1-2*exp(-25)
+ c0 = 1.42343711074968357734e0
+ c1 = 4.63033784615654529590e0
+ c2 = 5.76949722146069140550e0
+ c3 = 3.64784832476320460504e0
+ c4 = 1.27045825245236838258e0
+ c5 = 2.41780725177450611770e-1
+ c6 = 2.27238449892691845833e-2
+ c7 = 7.74545014278341407640e-4
+ d0 = 1.4142135623730950488016887e0
+ d1 = 2.9036514445419946173133295e0
+ d2 = 2.3707661626024532365971225e0
+ d3 = 9.7547832001787427186894837e-1
+ d4 = 2.0945065210512749128288442e-1
+ d5 = 2.1494160384252876777097297e-2
+ d6 = 7.7441459065157709165577218e-4
+ d7 = 1.4859850019840355905497876e-9
+ // Coefficients for approximation to erf in 1-2*exp(-25) < |x| < 1
+ e0 = 6.65790464350110377720e0
+ e1 = 5.46378491116411436990e0
+ e2 = 1.78482653991729133580e0
+ e3 = 2.96560571828504891230e-1
+ e4 = 2.65321895265761230930e-2
+ e5 = 1.24266094738807843860e-3
+ e6 = 2.71155556874348757815e-5
+ e7 = 2.01033439929228813265e-7
+ f0 = 1.414213562373095048801689e0
+ f1 = 8.482908416595164588112026e-1
+ f2 = 1.936480946950659106176712e-1
+ f3 = 2.103693768272068968719679e-2
+ f4 = 1.112800997078859844711555e-3
+ f5 = 2.611088405080593625138020e-5
+ f6 = 2.010321207683943062279931e-7
+ f7 = 2.891024605872965461538222e-15
+)
+
+// Erfinv returns the inverse error function of x.
+//
+// Special cases are:
+//
+// Erfinv(1) = +Inf
+// Erfinv(-1) = -Inf
+// Erfinv(x) = NaN if x < -1 or x > 1
+// Erfinv(NaN) = NaN
+func Erfinv(x float64) float64 {
+ // special cases
+ if IsNaN(x) || x <= -1 || x >= 1 {
+ if x == -1 || x == 1 {
+ return Inf(int(x))
+ }
+ return NaN()
+ }
+
+ sign := false
+ if x < 0 {
+ x = -x
+ sign = true
+ }
+
+ var ans float64
+ if x <= 0.85 { // |x| <= 0.85
+ r := 0.180625 - 0.25*x*x
+ z1 := ((((((a7*r+a6)*r+a5)*r+a4)*r+a3)*r+a2)*r+a1)*r + a0
+ z2 := ((((((b7*r+b6)*r+b5)*r+b4)*r+b3)*r+b2)*r+b1)*r + b0
+ ans = (x * z1) / z2
+ } else {
+ var z1, z2 float64
+ r := Sqrt(Ln2 - Log(1.0-x))
+ if r <= 5.0 {
+ r -= 1.6
+ z1 = ((((((c7*r+c6)*r+c5)*r+c4)*r+c3)*r+c2)*r+c1)*r + c0
+ z2 = ((((((d7*r+d6)*r+d5)*r+d4)*r+d3)*r+d2)*r+d1)*r + d0
+ } else {
+ r -= 5.0
+ z1 = ((((((e7*r+e6)*r+e5)*r+e4)*r+e3)*r+e2)*r+e1)*r + e0
+ z2 = ((((((f7*r+f6)*r+f5)*r+f4)*r+f3)*r+f2)*r+f1)*r + f0
+ }
+ ans = z1 / z2
+ }
+
+ if sign {
+ return -ans
+ }
+ return ans
+}
+
+// Erfcinv returns the inverse of [Erfc](x).
+//
+// Special cases are:
+//
+// Erfcinv(0) = +Inf
+// Erfcinv(2) = -Inf
+// Erfcinv(x) = NaN if x < 0 or x > 2
+// Erfcinv(NaN) = NaN
+func Erfcinv(x float64) float64 {
+ return Erfinv(1 - x)
+}
diff --git a/go/src/math/example_test.go b/go/src/math/example_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..a26d8cbe97d8b463cbcb1ea6e57197545a253dbc
--- /dev/null
+++ b/go/src/math/example_test.go
@@ -0,0 +1,245 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math_test
+
+import (
+ "fmt"
+ "math"
+)
+
+func ExampleAcos() {
+ fmt.Printf("%.2f", math.Acos(1))
+ // Output: 0.00
+}
+
+func ExampleAcosh() {
+ fmt.Printf("%.2f", math.Acosh(1))
+ // Output: 0.00
+}
+
+func ExampleAsin() {
+ fmt.Printf("%.2f", math.Asin(0))
+ // Output: 0.00
+}
+
+func ExampleAsinh() {
+ fmt.Printf("%.2f", math.Asinh(0))
+ // Output: 0.00
+}
+
+func ExampleAtan() {
+ fmt.Printf("%.2f", math.Atan(0))
+ // Output: 0.00
+}
+
+func ExampleAtan2() {
+ fmt.Printf("%.2f", math.Atan2(0, 0))
+ // Output: 0.00
+}
+
+func ExampleAtanh() {
+ fmt.Printf("%.2f", math.Atanh(0))
+ // Output: 0.00
+}
+
+func ExampleCopysign() {
+ fmt.Printf("%.2f", math.Copysign(3.2, -1))
+ // Output: -3.20
+}
+
+func ExampleCos() {
+ fmt.Printf("%.2f", math.Cos(math.Pi/2))
+ // Output: 0.00
+}
+
+func ExampleCosh() {
+ fmt.Printf("%.2f", math.Cosh(0))
+ // Output: 1.00
+}
+
+func ExampleSin() {
+ fmt.Printf("%.2f", math.Sin(math.Pi))
+ // Output: 0.00
+}
+
+func ExampleSincos() {
+ sin, cos := math.Sincos(0)
+ fmt.Printf("%.2f, %.2f", sin, cos)
+ // Output: 0.00, 1.00
+}
+
+func ExampleSinh() {
+ fmt.Printf("%.2f", math.Sinh(0))
+ // Output: 0.00
+}
+
+func ExampleTan() {
+ fmt.Printf("%.2f", math.Tan(0))
+ // Output: 0.00
+}
+
+func ExampleTanh() {
+ fmt.Printf("%.2f", math.Tanh(0))
+ // Output: 0.00
+}
+
+func ExampleSqrt() {
+ const (
+ a = 3
+ b = 4
+ )
+ c := math.Sqrt(a*a + b*b)
+ fmt.Printf("%.1f", c)
+ // Output: 5.0
+}
+
+func ExampleCeil() {
+ c := math.Ceil(1.49)
+ fmt.Printf("%.1f", c)
+ // Output: 2.0
+}
+
+func ExampleFloor() {
+ c := math.Floor(1.51)
+ fmt.Printf("%.1f", c)
+ // Output: 1.0
+}
+
+func ExamplePow() {
+ c := math.Pow(2, 3)
+ fmt.Printf("%.1f", c)
+ // Output: 8.0
+}
+
+func ExamplePow10() {
+ c := math.Pow10(2)
+ fmt.Printf("%.1f", c)
+ // Output: 100.0
+}
+
+func ExampleRound() {
+ p := math.Round(10.5)
+ fmt.Printf("%.1f\n", p)
+
+ n := math.Round(-10.5)
+ fmt.Printf("%.1f\n", n)
+ // Output:
+ // 11.0
+ // -11.0
+}
+
+func ExampleRoundToEven() {
+ u := math.RoundToEven(11.5)
+ fmt.Printf("%.1f\n", u)
+
+ d := math.RoundToEven(12.5)
+ fmt.Printf("%.1f\n", d)
+ // Output:
+ // 12.0
+ // 12.0
+}
+
+func ExampleLog() {
+ x := math.Log(1)
+ fmt.Printf("%.1f\n", x)
+
+ y := math.Log(2.7183)
+ fmt.Printf("%.1f\n", y)
+ // Output:
+ // 0.0
+ // 1.0
+}
+
+func ExampleLog2() {
+ fmt.Printf("%.1f", math.Log2(256))
+ // Output: 8.0
+}
+
+func ExampleLog10() {
+ fmt.Printf("%.1f", math.Log10(100))
+ // Output: 2.0
+}
+
+func ExampleRemainder() {
+ fmt.Printf("%.1f", math.Remainder(100, 30))
+ // Output: 10.0
+}
+
+func ExampleMod() {
+ c := math.Mod(7, 4)
+ fmt.Printf("%.1f", c)
+ // Output: 3.0
+}
+
+func ExampleAbs() {
+ x := math.Abs(-2)
+ fmt.Printf("%.1f\n", x)
+
+ y := math.Abs(2)
+ fmt.Printf("%.1f\n", y)
+ // Output:
+ // 2.0
+ // 2.0
+}
+func ExampleDim() {
+ fmt.Printf("%.2f\n", math.Dim(4, -2))
+ fmt.Printf("%.2f\n", math.Dim(-4, 2))
+ // Output:
+ // 6.00
+ // 0.00
+}
+
+func ExampleExp() {
+ fmt.Printf("%.2f\n", math.Exp(1))
+ fmt.Printf("%.2f\n", math.Exp(2))
+ fmt.Printf("%.2f\n", math.Exp(-1))
+ // Output:
+ // 2.72
+ // 7.39
+ // 0.37
+}
+
+func ExampleExp2() {
+ fmt.Printf("%.2f\n", math.Exp2(1))
+ fmt.Printf("%.2f\n", math.Exp2(-3))
+ // Output:
+ // 2.00
+ // 0.12
+}
+
+func ExampleExpm1() {
+ fmt.Printf("%.6f\n", math.Expm1(0.01))
+ fmt.Printf("%.6f\n", math.Expm1(-1))
+ // Output:
+ // 0.010050
+ // -0.632121
+}
+
+func ExampleTrunc() {
+ fmt.Printf("%.2f\n", math.Trunc(math.Pi))
+ fmt.Printf("%.2f\n", math.Trunc(-1.2345))
+ // Output:
+ // 3.00
+ // -1.00
+}
+
+func ExampleCbrt() {
+ fmt.Printf("%.2f\n", math.Cbrt(8))
+ fmt.Printf("%.2f\n", math.Cbrt(27))
+ // Output:
+ // 2.00
+ // 3.00
+}
+
+func ExampleModf() {
+ int, frac := math.Modf(3.14)
+ fmt.Printf("%.2f, %.2f\n", int, frac)
+
+ int, frac = math.Modf(-2.71)
+ fmt.Printf("%.2f, %.2f\n", int, frac)
+ // Output:
+ // 3.00, 0.14
+ // -2.00, -0.71
+}
diff --git a/go/src/math/exp.go b/go/src/math/exp.go
new file mode 100644
index 0000000000000000000000000000000000000000..029a4f8163698fe694c8c9375ae189d80cb31671
--- /dev/null
+++ b/go/src/math/exp.go
@@ -0,0 +1,199 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Exp returns e**x, the base-e exponential of x.
+//
+// Special cases are:
+//
+// Exp(+Inf) = +Inf
+// Exp(NaN) = NaN
+//
+// Very large values overflow to 0 or +Inf.
+// Very small values underflow to 1.
+func Exp(x float64) float64 {
+ if haveArchExp {
+ return archExp(x)
+ }
+ return exp(x)
+}
+
+// The original C code, the long comment, and the constants
+// below are from FreeBSD's /usr/src/lib/msun/src/e_exp.c
+// and came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 2004 by Sun Microsystems, Inc. All rights reserved.
+//
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+//
+// exp(x)
+// Returns the exponential of x.
+//
+// Method
+// 1. Argument reduction:
+// Reduce x to an r so that |r| <= 0.5*ln2 ~ 0.34658.
+// Given x, find r and integer k such that
+//
+// x = k*ln2 + r, |r| <= 0.5*ln2.
+//
+// Here r will be represented as r = hi-lo for better
+// accuracy.
+//
+// 2. Approximation of exp(r) by a special rational function on
+// the interval [0,0.34658]:
+// Write
+// R(r**2) = r*(exp(r)+1)/(exp(r)-1) = 2 + r*r/6 - r**4/360 + ...
+// We use a special Remez algorithm on [0,0.34658] to generate
+// a polynomial of degree 5 to approximate R. The maximum error
+// of this polynomial approximation is bounded by 2**-59. In
+// other words,
+// R(z) ~ 2.0 + P1*z + P2*z**2 + P3*z**3 + P4*z**4 + P5*z**5
+// (where z=r*r, and the values of P1 to P5 are listed below)
+// and
+// | 5 | -59
+// | 2.0+P1*z+...+P5*z - R(z) | <= 2
+// | |
+// The computation of exp(r) thus becomes
+// 2*r
+// exp(r) = 1 + -------
+// R - r
+// r*R1(r)
+// = 1 + r + ----------- (for better accuracy)
+// 2 - R1(r)
+// where
+// 2 4 10
+// R1(r) = r - (P1*r + P2*r + ... + P5*r ).
+//
+// 3. Scale back to obtain exp(x):
+// From step 1, we have
+// exp(x) = 2**k * exp(r)
+//
+// Special cases:
+// exp(INF) is INF, exp(NaN) is NaN;
+// exp(-INF) is 0, and
+// for finite argument, only exp(0)=1 is exact.
+//
+// Accuracy:
+// according to an error analysis, the error is always less than
+// 1 ulp (unit in the last place).
+//
+// Misc. info.
+// For IEEE double
+// if x > 7.09782712893383973096e+02 then exp(x) overflow
+// if x < -7.45133219101941108420e+02 then exp(x) underflow
+//
+// Constants:
+// The hexadecimal values are the intended ones for the following
+// constants. The decimal values may be used, provided that the
+// compiler will convert from decimal to binary accurately enough
+// to produce the hexadecimal values shown.
+
+func exp(x float64) float64 {
+ const (
+ Ln2Hi = 6.93147180369123816490e-01
+ Ln2Lo = 1.90821492927058770002e-10
+ Log2e = 1.44269504088896338700e+00
+
+ Overflow = 7.09782712893383973096e+02
+ Underflow = -7.45133219101941108420e+02
+ NearZero = 1.0 / (1 << 28) // 2**-28
+ )
+
+ // special cases
+ switch {
+ case IsNaN(x):
+ return x
+ case x > Overflow: // handles case where x is +∞
+ return Inf(1)
+ case x < Underflow: // handles case where x is -∞
+ return 0
+ case -NearZero < x && x < NearZero:
+ return 1 + x
+ }
+
+ // reduce; computed as r = hi - lo for extra precision.
+ var k int
+ switch {
+ case x < 0:
+ k = int(Log2e*x - 0.5)
+ case x > 0:
+ k = int(Log2e*x + 0.5)
+ }
+ hi := x - float64(k)*Ln2Hi
+ lo := float64(k) * Ln2Lo
+
+ // compute
+ return expmulti(hi, lo, k)
+}
+
+// Exp2 returns 2**x, the base-2 exponential of x.
+//
+// Special cases are the same as [Exp].
+func Exp2(x float64) float64 {
+ if haveArchExp2 {
+ return archExp2(x)
+ }
+ return exp2(x)
+}
+
+func exp2(x float64) float64 {
+ const (
+ Ln2Hi = 6.93147180369123816490e-01
+ Ln2Lo = 1.90821492927058770002e-10
+
+ Overflow = 1.0239999999999999e+03
+ Underflow = -1.0740e+03
+ )
+
+ // special cases
+ switch {
+ case IsNaN(x):
+ return x
+ case x > Overflow: // handles case where x is +∞
+ return Inf(1)
+ case x < Underflow: // handles case where x is -∞
+ return 0
+ }
+
+ // argument reduction; x = r×lg(e) + k with |r| ≤ ln(2)/2.
+ // computed as r = hi - lo for extra precision.
+ var k int
+ switch {
+ case x > 0:
+ k = int(x + 0.5)
+ case x < 0:
+ k = int(x - 0.5)
+ }
+ t := x - float64(k)
+ hi := t * Ln2Hi
+ lo := -t * Ln2Lo
+
+ // compute
+ return expmulti(hi, lo, k)
+}
+
+// exp1 returns e**r × 2**k where r = hi - lo and |r| ≤ ln(2)/2.
+func expmulti(hi, lo float64, k int) float64 {
+ const (
+ P1 = 1.66666666666666657415e-01 /* 0x3FC55555; 0x55555555 */
+ P2 = -2.77777777770155933842e-03 /* 0xBF66C16C; 0x16BEBD93 */
+ P3 = 6.61375632143793436117e-05 /* 0x3F11566A; 0xAF25DE2C */
+ P4 = -1.65339022054652515390e-06 /* 0xBEBBBD41; 0xC5D26BF1 */
+ P5 = 4.13813679705723846039e-08 /* 0x3E663769; 0x72BEA4D0 */
+ )
+
+ r := hi - lo
+ t := r * r
+ c := r - t*(P1+t*(P2+t*(P3+t*(P4+t*P5))))
+ y := 1 - ((lo - (r*c)/(2-c)) - hi)
+ // TODO(rsc): make sure Ldexp can handle boundary k
+ return Ldexp(y, k)
+}
diff --git a/go/src/math/exp2_asm.go b/go/src/math/exp2_asm.go
new file mode 100644
index 0000000000000000000000000000000000000000..1e7875937432e83b0107ba10740a6a6173863730
--- /dev/null
+++ b/go/src/math/exp2_asm.go
@@ -0,0 +1,11 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build arm64 || loong64
+
+package math
+
+const haveArchExp2 = true
+
+func archExp2(x float64) float64
diff --git a/go/src/math/exp2_noasm.go b/go/src/math/exp2_noasm.go
new file mode 100644
index 0000000000000000000000000000000000000000..847138b622ce671b10355597720600a7a79d7377
--- /dev/null
+++ b/go/src/math/exp2_noasm.go
@@ -0,0 +1,13 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !arm64 && !loong64
+
+package math
+
+const haveArchExp2 = false
+
+func archExp2(x float64) float64 {
+ panic("not implemented")
+}
diff --git a/go/src/math/exp_amd64.go b/go/src/math/exp_amd64.go
new file mode 100644
index 0000000000000000000000000000000000000000..0f701b1d6d8da1fa4bf3c8e14c3c45bb348df9d2
--- /dev/null
+++ b/go/src/math/exp_amd64.go
@@ -0,0 +1,11 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build amd64
+
+package math
+
+import "internal/cpu"
+
+var useFMA = cpu.X86.HasAVX && cpu.X86.HasFMA
diff --git a/go/src/math/exp_amd64.s b/go/src/math/exp_amd64.s
new file mode 100644
index 0000000000000000000000000000000000000000..02b71c81eb636c06dc396102ac7d3024defcf246
--- /dev/null
+++ b/go/src/math/exp_amd64.s
@@ -0,0 +1,159 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// The method is based on a paper by Naoki Shibata: "Efficient evaluation
+// methods of elementary functions suitable for SIMD computation", Proc.
+// of International Supercomputing Conference 2010 (ISC'10), pp. 25 -- 32
+// (May 2010). The paper is available at
+// https://link.springer.com/article/10.1007/s00450-010-0108-2
+//
+// The original code and the constants below are from the author's
+// implementation available at http://freshmeat.net/projects/sleef.
+// The README file says, "The software is in public domain.
+// You can use the software without any obligation."
+//
+// This code is a simplified version of the original.
+
+#define LN2 0.6931471805599453094172321214581766 // log_e(2)
+#define LOG2E 1.4426950408889634073599246810018920 // 1/LN2
+#define LN2U 0.69314718055966295651160180568695068359375 // upper half LN2
+#define LN2L 0.28235290563031577122588448175013436025525412068e-12 // lower half LN2
+#define PosInf 0x7FF0000000000000
+#define NegInf 0xFFF0000000000000
+#define Overflow 7.09782712893384e+02
+
+DATA exprodata<>+0(SB)/8, $0.5
+DATA exprodata<>+8(SB)/8, $1.0
+DATA exprodata<>+16(SB)/8, $2.0
+DATA exprodata<>+24(SB)/8, $1.6666666666666666667e-1
+DATA exprodata<>+32(SB)/8, $4.1666666666666666667e-2
+DATA exprodata<>+40(SB)/8, $8.3333333333333333333e-3
+DATA exprodata<>+48(SB)/8, $1.3888888888888888889e-3
+DATA exprodata<>+56(SB)/8, $1.9841269841269841270e-4
+DATA exprodata<>+64(SB)/8, $2.4801587301587301587e-5
+GLOBL exprodata<>+0(SB), RODATA, $72
+
+// func Exp(x float64) float64
+TEXT ·archExp(SB),NOSPLIT,$0
+ // test bits for not-finite
+ MOVQ x+0(FP), BX
+ MOVQ $~(1<<63), AX // sign bit mask
+ MOVQ BX, DX
+ ANDQ AX, DX
+ MOVQ $PosInf, AX
+ CMPQ AX, DX
+ JLE notFinite
+ // check if argument will overflow
+ MOVQ BX, X0
+ MOVSD $Overflow, X1
+ COMISD X1, X0
+ JA overflow
+ MOVSD $LOG2E, X1
+ MULSD X0, X1
+ CVTSD2SL X1, BX // BX = exponent
+ CVTSL2SD BX, X1
+ CMPB ·useFMA(SB), $1
+ JE avxfma
+ MOVSD $LN2U, X2
+ MULSD X1, X2
+ SUBSD X2, X0
+ MOVSD $LN2L, X2
+ MULSD X1, X2
+ SUBSD X2, X0
+ // reduce argument
+ MULSD $0.0625, X0
+ // Taylor series evaluation
+ MOVSD exprodata<>+64(SB), X1
+ MULSD X0, X1
+ ADDSD exprodata<>+56(SB), X1
+ MULSD X0, X1
+ ADDSD exprodata<>+48(SB), X1
+ MULSD X0, X1
+ ADDSD exprodata<>+40(SB), X1
+ MULSD X0, X1
+ ADDSD exprodata<>+32(SB), X1
+ MULSD X0, X1
+ ADDSD exprodata<>+24(SB), X1
+ MULSD X0, X1
+ ADDSD exprodata<>+0(SB), X1
+ MULSD X0, X1
+ ADDSD exprodata<>+8(SB), X1
+ MULSD X1, X0
+ MOVSD exprodata<>+16(SB), X1
+ ADDSD X0, X1
+ MULSD X1, X0
+ MOVSD exprodata<>+16(SB), X1
+ ADDSD X0, X1
+ MULSD X1, X0
+ MOVSD exprodata<>+16(SB), X1
+ ADDSD X0, X1
+ MULSD X1, X0
+ MOVSD exprodata<>+16(SB), X1
+ ADDSD X0, X1
+ MULSD X1, X0
+ ADDSD exprodata<>+8(SB), X0
+ // return fr * 2**exponent
+ldexp:
+ ADDL $0x3FF, BX // add bias
+ JLE denormal
+ CMPL BX, $0x7FF
+ JGE overflow
+lastStep:
+ SHLQ $52, BX
+ MOVQ BX, X1
+ MULSD X1, X0
+ MOVSD X0, ret+8(FP)
+ RET
+notFinite:
+ // test bits for -Inf
+ MOVQ $NegInf, AX
+ CMPQ AX, BX
+ JNE notNegInf
+ // -Inf, return 0
+underflow: // return 0
+ MOVQ $0, ret+8(FP)
+ RET
+overflow: // return +Inf
+ MOVQ $PosInf, BX
+notNegInf: // NaN or +Inf, return x
+ MOVQ BX, ret+8(FP)
+ RET
+denormal:
+ CMPL BX, $-52
+ JL underflow
+ ADDL $0x3FE, BX // add bias - 1
+ SHLQ $52, BX
+ MOVQ BX, X1
+ MULSD X1, X0
+ MOVQ $1, BX
+ JMP lastStep
+
+avxfma:
+ MOVSD $LN2U, X2
+ VFNMADD231SD X2, X1, X0
+ MOVSD $LN2L, X2
+ VFNMADD231SD X2, X1, X0
+ // reduce argument
+ MULSD $0.0625, X0
+ // Taylor series evaluation
+ MOVSD exprodata<>+64(SB), X1
+ VFMADD213SD exprodata<>+56(SB), X0, X1
+ VFMADD213SD exprodata<>+48(SB), X0, X1
+ VFMADD213SD exprodata<>+40(SB), X0, X1
+ VFMADD213SD exprodata<>+32(SB), X0, X1
+ VFMADD213SD exprodata<>+24(SB), X0, X1
+ VFMADD213SD exprodata<>+0(SB), X0, X1
+ VFMADD213SD exprodata<>+8(SB), X0, X1
+ MULSD X1, X0
+ VADDSD exprodata<>+16(SB), X0, X1
+ MULSD X1, X0
+ VADDSD exprodata<>+16(SB), X0, X1
+ MULSD X1, X0
+ VADDSD exprodata<>+16(SB), X0, X1
+ MULSD X1, X0
+ VADDSD exprodata<>+16(SB), X0, X1
+ VFMADD213SD exprodata<>+8(SB), X1, X0
+ JMP ldexp
diff --git a/go/src/math/exp_arm64.s b/go/src/math/exp_arm64.s
new file mode 100644
index 0000000000000000000000000000000000000000..44673abefe4cce681346455a6928746b3354b33a
--- /dev/null
+++ b/go/src/math/exp_arm64.s
@@ -0,0 +1,182 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#define Ln2Hi 6.93147180369123816490e-01
+#define Ln2Lo 1.90821492927058770002e-10
+#define Log2e 1.44269504088896338700e+00
+#define Overflow 7.09782712893383973096e+02
+#define Underflow -7.45133219101941108420e+02
+#define Overflow2 1.0239999999999999e+03
+#define Underflow2 -1.0740e+03
+#define NearZero 0x3e30000000000000 // 2**-28
+#define PosInf 0x7ff0000000000000
+#define FracMask 0x000fffffffffffff
+#define C1 0x3cb0000000000000 // 2**-52
+#define P1 1.66666666666666657415e-01 // 0x3FC55555; 0x55555555
+#define P2 -2.77777777770155933842e-03 // 0xBF66C16C; 0x16BEBD93
+#define P3 6.61375632143793436117e-05 // 0x3F11566A; 0xAF25DE2C
+#define P4 -1.65339022054652515390e-06 // 0xBEBBBD41; 0xC5D26BF1
+#define P5 4.13813679705723846039e-08 // 0x3E663769; 0x72BEA4D0
+
+// Exp returns e**x, the base-e exponential of x.
+// This is an assembly implementation of the method used for function Exp in file exp.go.
+//
+// func Exp(x float64) float64
+TEXT ·archExp(SB),$0-16
+ FMOVD x+0(FP), F0 // F0 = x
+ FCMPD F0, F0
+ BNE isNaN // x = NaN, return NaN
+ FMOVD $Overflow, F1
+ FCMPD F1, F0
+ BGT overflow // x > Overflow, return PosInf
+ FMOVD $Underflow, F1
+ FCMPD F1, F0
+ BLT underflow // x < Underflow, return 0
+ MOVD $NearZero, R0
+ FMOVD R0, F2
+ FABSD F0, F3
+ FMOVD $1.0, F1 // F1 = 1.0
+ FCMPD F2, F3
+ BLT nearzero // fabs(x) < NearZero, return 1 + x
+ // argument reduction, x = k*ln2 + r, |r| <= 0.5*ln2
+ // computed as r = hi - lo for extra precision.
+ FMOVD $Log2e, F2
+ FMOVD $0.5, F3
+ FNMSUBD F0, F3, F2, F4 // Log2e*x - 0.5
+ FMADDD F0, F3, F2, F3 // Log2e*x + 0.5
+ FCMPD $0.0, F0
+ FCSELD LT, F4, F3, F3 // F3 = k
+ FCVTZSD F3, R1 // R1 = int(k)
+ SCVTFD R1, F3 // F3 = float64(int(k))
+ FMOVD $Ln2Hi, F4 // F4 = Ln2Hi
+ FMOVD $Ln2Lo, F5 // F5 = Ln2Lo
+ FMSUBD F3, F0, F4, F4 // F4 = hi = x - float64(int(k))*Ln2Hi
+ FMULD F3, F5 // F5 = lo = float64(int(k)) * Ln2Lo
+ FSUBD F5, F4, F6 // F6 = r = hi - lo
+ FMULD F6, F6, F7 // F7 = t = r * r
+ // compute y
+ FMOVD $P5, F8 // F8 = P5
+ FMOVD $P4, F9 // F9 = P4
+ FMADDD F7, F9, F8, F13 // P4+t*P5
+ FMOVD $P3, F10 // F10 = P3
+ FMADDD F7, F10, F13, F13 // P3+t*(P4+t*P5)
+ FMOVD $P2, F11 // F11 = P2
+ FMADDD F7, F11, F13, F13 // P2+t*(P3+t*(P4+t*P5))
+ FMOVD $P1, F12 // F12 = P1
+ FMADDD F7, F12, F13, F13 // P1+t*(P2+t*(P3+t*(P4+t*P5)))
+ FMSUBD F7, F6, F13, F13 // F13 = c = r - t*(P1+t*(P2+t*(P3+t*(P4+t*P5))))
+ FMOVD $2.0, F14
+ FSUBD F13, F14
+ FMULD F6, F13, F15
+ FDIVD F14, F15 // F15 = (r*c)/(2-c)
+ FSUBD F15, F5, F15 // lo-(r*c)/(2-c)
+ FSUBD F4, F15, F15 // (lo-(r*c)/(2-c))-hi
+ FSUBD F15, F1, F16 // F16 = y = 1-((lo-(r*c)/(2-c))-hi)
+ // inline Ldexp(y, k), benefit:
+ // 1, no parameter pass overhead.
+ // 2, skip unnecessary checks for Inf/NaN/Zero
+ FMOVD F16, R0
+ AND $FracMask, R0, R2 // fraction
+ LSR $52, R0, R5 // exponent
+ ADD R1, R5 // R1 = int(k)
+ CMP $1, R5
+ BGE normal
+ ADD $52, R5 // denormal
+ MOVD $C1, R8
+ FMOVD R8, F1 // m = 2**-52
+normal:
+ ORR R5<<52, R2, R0
+ FMOVD R0, F0
+ FMULD F1, F0 // return m * x
+ FMOVD F0, ret+8(FP)
+ RET
+nearzero:
+ FADDD F1, F0
+isNaN:
+ FMOVD F0, ret+8(FP)
+ RET
+underflow:
+ MOVD ZR, ret+8(FP)
+ RET
+overflow:
+ MOVD $PosInf, R0
+ MOVD R0, ret+8(FP)
+ RET
+
+
+// Exp2 returns 2**x, the base-2 exponential of x.
+// This is an assembly implementation of the method used for function Exp2 in file exp.go.
+//
+// func Exp2(x float64) float64
+TEXT ·archExp2(SB),$0-16
+ FMOVD x+0(FP), F0 // F0 = x
+ FCMPD F0, F0
+ BNE isNaN // x = NaN, return NaN
+ FMOVD $Overflow2, F1
+ FCMPD F1, F0
+ BGT overflow // x > Overflow, return PosInf
+ FMOVD $Underflow2, F1
+ FCMPD F1, F0
+ BLT underflow // x < Underflow, return 0
+ // argument reduction; x = r*lg(e) + k with |r| <= ln(2)/2
+ // computed as r = hi - lo for extra precision.
+ FMOVD $0.5, F2
+ FSUBD F2, F0, F3 // x + 0.5
+ FADDD F2, F0, F4 // x - 0.5
+ FCMPD $0.0, F0
+ FCSELD LT, F3, F4, F3 // F3 = k
+ FCVTZSD F3, R1 // R1 = int(k)
+ SCVTFD R1, F3 // F3 = float64(int(k))
+ FSUBD F3, F0, F3 // t = x - float64(int(k))
+ FMOVD $Ln2Hi, F4 // F4 = Ln2Hi
+ FMOVD $Ln2Lo, F5 // F5 = Ln2Lo
+ FMULD F3, F4 // F4 = hi = t * Ln2Hi
+ FNMULD F3, F5 // F5 = lo = -t * Ln2Lo
+ FSUBD F5, F4, F6 // F6 = r = hi - lo
+ FMULD F6, F6, F7 // F7 = t = r * r
+ // compute y
+ FMOVD $P5, F8 // F8 = P5
+ FMOVD $P4, F9 // F9 = P4
+ FMADDD F7, F9, F8, F13 // P4+t*P5
+ FMOVD $P3, F10 // F10 = P3
+ FMADDD F7, F10, F13, F13 // P3+t*(P4+t*P5)
+ FMOVD $P2, F11 // F11 = P2
+ FMADDD F7, F11, F13, F13 // P2+t*(P3+t*(P4+t*P5))
+ FMOVD $P1, F12 // F12 = P1
+ FMADDD F7, F12, F13, F13 // P1+t*(P2+t*(P3+t*(P4+t*P5)))
+ FMSUBD F7, F6, F13, F13 // F13 = c = r - t*(P1+t*(P2+t*(P3+t*(P4+t*P5))))
+ FMOVD $2.0, F14
+ FSUBD F13, F14
+ FMULD F6, F13, F15
+ FDIVD F14, F15 // F15 = (r*c)/(2-c)
+ FMOVD $1.0, F1 // F1 = 1.0
+ FSUBD F15, F5, F15 // lo-(r*c)/(2-c)
+ FSUBD F4, F15, F15 // (lo-(r*c)/(2-c))-hi
+ FSUBD F15, F1, F16 // F16 = y = 1-((lo-(r*c)/(2-c))-hi)
+ // inline Ldexp(y, k), benefit:
+ // 1, no parameter pass overhead.
+ // 2, skip unnecessary checks for Inf/NaN/Zero
+ FMOVD F16, R0
+ AND $FracMask, R0, R2 // fraction
+ LSR $52, R0, R5 // exponent
+ ADD R1, R5 // R1 = int(k)
+ CMP $1, R5
+ BGE normal
+ ADD $52, R5 // denormal
+ MOVD $C1, R8
+ FMOVD R8, F1 // m = 2**-52
+normal:
+ ORR R5<<52, R2, R0
+ FMOVD R0, F0
+ FMULD F1, F0 // return m * x
+isNaN:
+ FMOVD F0, ret+8(FP)
+ RET
+underflow:
+ MOVD ZR, ret+8(FP)
+ RET
+overflow:
+ MOVD $PosInf, R0
+ MOVD R0, ret+8(FP)
+ RET
diff --git a/go/src/math/exp_asm.go b/go/src/math/exp_asm.go
new file mode 100644
index 0000000000000000000000000000000000000000..125529fca360a206d082fb950bb4dd18da845ed8
--- /dev/null
+++ b/go/src/math/exp_asm.go
@@ -0,0 +1,11 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build amd64 || arm64 || loong64 || s390x
+
+package math
+
+const haveArchExp = true
+
+func archExp(x float64) float64
diff --git a/go/src/math/exp_loong64.s b/go/src/math/exp_loong64.s
new file mode 100644
index 0000000000000000000000000000000000000000..bf2823f888510b61562d1b1490dc7bf3dd227e84
--- /dev/null
+++ b/go/src/math/exp_loong64.s
@@ -0,0 +1,236 @@
+// Copyright 2025 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+#define NearZero 0x3e30000000000000 // 2**-28
+#define PosInf 0x7ff0000000000000
+#define FracMask 0x000fffffffffffff
+#define C1 0x3cb0000000000000 // 2**-52
+
+DATA exprodata<>+0(SB)/8, $0.0
+DATA exprodata<>+8(SB)/8, $0.5
+DATA exprodata<>+16(SB)/8, $1.0
+DATA exprodata<>+24(SB)/8, $2.0
+DATA exprodata<>+32(SB)/8, $6.93147180369123816490e-01 // Ln2Hi
+DATA exprodata<>+40(SB)/8, $1.90821492927058770002e-10 // Ln2Lo
+DATA exprodata<>+48(SB)/8, $1.44269504088896338700e+00 // Log2e
+DATA exprodata<>+56(SB)/8, $7.09782712893383973096e+02 // Overflow
+DATA exprodata<>+64(SB)/8, $-7.45133219101941108420e+02 // Underflow
+DATA exprodata<>+72(SB)/8, $1.0239999999999999e+03 // Overflow2
+DATA exprodata<>+80(SB)/8, $-1.0740e+03 // Underflow2
+DATA exprodata<>+88(SB)/8, $3.7252902984619141e-09 // NearZero
+GLOBL exprodata<>+0(SB), NOPTR|RODATA, $96
+
+DATA expmultirodata<>+0(SB)/8, $1.66666666666666657415e-01 // P1
+DATA expmultirodata<>+8(SB)/8, $-2.77777777770155933842e-03 // P2
+DATA expmultirodata<>+16(SB)/8, $6.61375632143793436117e-05 // P3
+DATA expmultirodata<>+24(SB)/8, $-1.65339022054652515390e-06 // P4
+DATA expmultirodata<>+32(SB)/8, $4.13813679705723846039e-08 // P5
+GLOBL expmultirodata<>+0(SB), NOPTR|RODATA, $40
+
+// Exp returns e**x, the base-e exponential of x.
+// This is an assembly implementation of the method used for function Exp in file exp.go.
+//
+// func Exp(x float64) float64
+TEXT ·archExp(SB),$0-16
+ MOVD x+0(FP), F0 // F0 = x
+
+ MOVV $exprodata<>+0(SB), R10
+ MOVD 56(R10), F1 // Overflow
+ MOVD 64(R10), F2 // Underflow
+ MOVD 88(R10), F3 // NearZero
+ MOVD 16(R10), F17 // 1.0
+
+ CMPEQD F0, F0, FCC0
+ BFPF isNaN // x = NaN, return NaN
+
+ CMPGTD F0, F1, FCC0
+ BFPT overflow // x > Overflow, return PosInf
+
+ CMPGTD F2, F0, FCC0
+ BFPT underflow // x < Underflow, return 0
+
+ ABSD F0, F5
+ CMPGTD F3, F5, FCC0
+ BFPT nearzero // fabs(x) < NearZero, return 1 + x
+
+ // argument reduction, x = k*ln2 + r, |r| <= 0.5*ln2
+ // computed as r = hi - lo for extra precision.
+ MOVD 0(R10), F5
+ MOVD 8(R10), F3
+ MOVD 48(R10), F2
+ CMPGTD F0, F5, FCC0
+ BFPT add // x > 0
+sub:
+ FMSUBD F3, F2, F0, F3 // Log2e*x - 0.5
+ JMP 2(PC)
+add:
+ FMADDD F3, F2, F0, F3 // Log2e*x + 0.5
+
+ FTINTRZVD F3, F4 // float64 -> int64
+ MOVV F4, R5 // R5 = int(k)
+ FFINTDV F4, F3 // int64 -> float64
+
+ MOVD 32(R10), F4
+ MOVD 40(R10), F5
+ FNMSUBD F0, F3, F4, F4
+ MULD F3, F5, F5
+ SUBD F5, F4, F6
+ MULD F6, F6, F7
+
+ // compute c
+ MOVV $expmultirodata<>+0(SB), R11
+ MOVD 32(R11), F8
+ MOVD 24(R11), F9
+ FMADDD F9, F8, F7, F13
+ MOVD 16(R11), F10
+ FMADDD F10, F13, F7, F13
+ MOVD 8(R11), F11
+ FMADDD F11, F13, F7, F13
+ MOVD 0(R11), F12
+ FMADDD F12, F13, F7, F13
+ FNMSUBD F6, F13, F7, F13
+
+ // compute y
+ MOVD 24(R10), F14
+ SUBD F13, F14, F14
+ MULD F6, F13, F15
+ DIVD F14, F15, F15
+ SUBD F15, F5, F15
+ SUBD F4, F15, F15
+ SUBD F15, F17, F16
+
+ // inline Ldexp(y, k), benefit:
+ // 1, no parameter pass overhead.
+ // 2, skip unnecessary checks for Inf/NaN/Zero
+ MOVV F16, R4
+ MOVV $FracMask, R9
+ AND R9, R4, R6 // fraction
+ SRLV $52, R4, R7 // exponent
+ ADDV R5, R7
+ MOVV $1, R12
+ BGE R7, R12, normal
+ ADDV $52, R7 // denormal
+ MOVV $C1, R8
+ MOVV R8, F17
+normal:
+ SLLV $52, R7
+ OR R7, R6, R4
+ MOVV R4, F0
+ MULD F17, F0 // return m * x
+ MOVD F0, ret+8(FP)
+ RET
+nearzero:
+ ADDD F17, F0, F0
+isNaN:
+ MOVD F0, ret+8(FP)
+ RET
+underflow:
+ MOVV R0, ret+8(FP)
+ RET
+overflow:
+ MOVV $PosInf, R4
+ MOVV R4, ret+8(FP)
+ RET
+
+
+// Exp2 returns 2**x, the base-2 exponential of x.
+// This is an assembly implementation of the method used for function Exp2 in file exp.go.
+//
+// func Exp2(x float64) float64
+TEXT ·archExp2(SB),$0-16
+ MOVD x+0(FP), F0 // F0 = x
+
+ MOVV $exprodata<>+0(SB), R10
+ MOVD 72(R10), F1 // Overflow2
+ MOVD 80(R10), F2 // Underflow2
+ MOVD 88(R10), F3 // NearZero
+
+ CMPEQD F0, F0, FCC0
+ BFPF isNaN // x = NaN, return NaN
+
+ CMPGTD F0, F1, FCC0
+ BFPT overflow // x > Overflow, return PosInf
+
+ CMPGTD F2, F0, FCC0
+ BFPT underflow // x < Underflow, return 0
+
+ // argument reduction; x = r*lg(e) + k with |r| <= ln(2)/2
+ // computed as r = hi - lo for extra precision.
+ MOVD 0(R10), F10
+ MOVD 8(R10), F2
+ CMPGTD F0, F10, FCC0
+ BFPT add
+sub:
+ SUBD F2, F0, F3 // x - 0.5
+ JMP 2(PC)
+add:
+ ADDD F2, F0, F3 // x + 0.5
+
+ FTINTRZVD F3, F4
+ MOVV F4, R5
+ FFINTDV F4, F3
+
+ MOVD 32(R10), F4
+ MOVD 40(R10), F5
+ SUBD F3, F0, F3
+ MULD F3, F4
+ FNMSUBD F10, F3, F5, F5
+ SUBD F5, F4, F6
+ MULD F6, F6, F7
+
+ // compute c
+ MOVV $expmultirodata<>+0(SB), R11
+ MOVD 32(R11), F8
+ MOVD 24(R11), F9
+ FMADDD F9, F8, F7, F13
+ MOVD 16(R11), F10
+ FMADDD F10, F13, F7, F13
+ MOVD 8(R11), F11
+ FMADDD F11, F13, F7, F13
+ MOVD 0(R11), F12
+ FMADDD F12, F13, F7, F13
+ FNMSUBD F6, F13, F7, F13
+
+ // compute y
+ MOVD 24(R10), F14
+ SUBD F13, F14, F14
+ MULD F6, F13, F15
+ DIVD F14, F15
+
+ MOVD 16(R10), F17
+ SUBD F15, F5, F15
+ SUBD F4, F15, F15
+ SUBD F15, F17, F16
+
+ // inline Ldexp(y, k), benefit:
+ // 1, no parameter pass overhead.
+ // 2, skip unnecessary checks for Inf/NaN/Zero
+ MOVV F16, R4
+ MOVV $FracMask, R9
+ SRLV $52, R4, R7 // exponent
+ AND R9, R4, R6 // fraction
+ ADDV R5, R7
+ MOVV $1, R12
+ BGE R7, R12, normal
+
+ ADDV $52, R7 // denormal
+ MOVV $C1, R8
+ MOVV R8, F17
+normal:
+ SLLV $52, R7
+ OR R7, R6, R4
+ MOVV R4, F0
+ MULD F17, F0
+isNaN:
+ MOVD F0, ret+8(FP)
+ RET
+underflow:
+ MOVV R0, ret+8(FP)
+ RET
+overflow:
+ MOVV $PosInf, R4
+ MOVV R4, ret+8(FP)
+ RET
diff --git a/go/src/math/exp_noasm.go b/go/src/math/exp_noasm.go
new file mode 100644
index 0000000000000000000000000000000000000000..bf5e84b736b26f700f6f7fb5c1569c28dfa4f17f
--- /dev/null
+++ b/go/src/math/exp_noasm.go
@@ -0,0 +1,13 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !amd64 && !arm64 && !loong64 && !s390x
+
+package math
+
+const haveArchExp = false
+
+func archExp(x float64) float64 {
+ panic("not implemented")
+}
diff --git a/go/src/math/exp_s390x.s b/go/src/math/exp_s390x.s
new file mode 100644
index 0000000000000000000000000000000000000000..baf0e985a1e2939410df95508eda904cf5613864
--- /dev/null
+++ b/go/src/math/exp_s390x.s
@@ -0,0 +1,177 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// Minimax polynomial approximation and other constants
+DATA ·exprodataL22<> + 0(SB)/8, $800.0E+00
+DATA ·exprodataL22<> + 8(SB)/8, $1.0000000000000022e+00
+DATA ·exprodataL22<> + 16(SB)/8, $0.500000000000004237e+00
+DATA ·exprodataL22<> + 24(SB)/8, $0.166666666630345592e+00
+DATA ·exprodataL22<> + 32(SB)/8, $0.138926439368309441e-02
+DATA ·exprodataL22<> + 40(SB)/8, $0.833349307718286047e-02
+DATA ·exprodataL22<> + 48(SB)/8, $0.416666664838056960e-01
+DATA ·exprodataL22<> + 56(SB)/8, $-.231904681384629956E-16
+DATA ·exprodataL22<> + 64(SB)/8, $-.693147180559945286E+00
+DATA ·exprodataL22<> + 72(SB)/8, $0.144269504088896339E+01
+DATA ·exprodataL22<> + 80(SB)/8, $704.0E+00
+GLOBL ·exprodataL22<> + 0(SB), RODATA, $88
+
+DATA ·expxinf<> + 0(SB)/8, $0x7ff0000000000000
+GLOBL ·expxinf<> + 0(SB), RODATA, $8
+DATA ·expx4ff<> + 0(SB)/8, $0x4ff0000000000000
+GLOBL ·expx4ff<> + 0(SB), RODATA, $8
+DATA ·expx2ff<> + 0(SB)/8, $0x2ff0000000000000
+GLOBL ·expx2ff<> + 0(SB), RODATA, $8
+DATA ·expxaddexp<> + 0(SB)/8, $0xc2f0000100003fef
+GLOBL ·expxaddexp<> + 0(SB), RODATA, $8
+
+// Log multipliers table
+DATA ·exptexp<> + 0(SB)/8, $0.442737824274138381E-01
+DATA ·exptexp<> + 8(SB)/8, $0.263602189790660309E-01
+DATA ·exptexp<> + 16(SB)/8, $0.122565642281703586E-01
+DATA ·exptexp<> + 24(SB)/8, $0.143757052860721398E-02
+DATA ·exptexp<> + 32(SB)/8, $-.651375034121276075E-02
+DATA ·exptexp<> + 40(SB)/8, $-.119317678849450159E-01
+DATA ·exptexp<> + 48(SB)/8, $-.150868749549871069E-01
+DATA ·exptexp<> + 56(SB)/8, $-.161992609578469234E-01
+DATA ·exptexp<> + 64(SB)/8, $-.154492360403337917E-01
+DATA ·exptexp<> + 72(SB)/8, $-.129850717389178721E-01
+DATA ·exptexp<> + 80(SB)/8, $-.892902649276657891E-02
+DATA ·exptexp<> + 88(SB)/8, $-.338202636596794887E-02
+DATA ·exptexp<> + 96(SB)/8, $0.357266307045684762E-02
+DATA ·exptexp<> + 104(SB)/8, $0.118665304327406698E-01
+DATA ·exptexp<> + 112(SB)/8, $0.214434994118118914E-01
+DATA ·exptexp<> + 120(SB)/8, $0.322580645161290314E-01
+GLOBL ·exptexp<> + 0(SB), RODATA, $128
+
+// Exp returns e**x, the base-e exponential of x.
+//
+// Special cases are:
+// Exp(+Inf) = +Inf
+// Exp(NaN) = NaN
+// Very large values overflow to 0 or +Inf.
+// Very small values underflow to 1.
+// The algorithm used is minimax polynomial approximation using a table of
+// polynomial coefficients determined with a Remez exchange algorithm.
+
+TEXT ·expAsm(SB), NOSPLIT, $0-16
+ FMOVD x+0(FP), F0
+ MOVD $·exprodataL22<>+0(SB), R5
+ LTDBR F0, F0
+ BLTU L20
+ FMOVD F0, F2
+L2:
+ WORD $0xED205050 //cdb %f2,.L23-.L22(%r5)
+ BYTE $0x00
+ BYTE $0x19
+ BGE L16
+ BVS L16
+ WFCEDBS V2, V2, V2
+ BVS LEXITTAGexp
+ MOVD $·expxaddexp<>+0(SB), R1
+ FMOVD 72(R5), F6
+ FMOVD 0(R1), F2
+ WFMSDB V0, V6, V2, V6
+ FMOVD 64(R5), F4
+ FADD F6, F2
+ FMOVD 56(R5), F1
+ FMADD F4, F2, F0
+ FMOVD 48(R5), F3
+ WFMADB V2, V1, V0, V2
+ FMOVD 40(R5), F1
+ FMOVD 32(R5), F4
+ FMUL F0, F0
+ WFMADB V2, V4, V1, V4
+ LGDR F6, R1
+ FMOVD 24(R5), F1
+ WFMADB V2, V3, V1, V3
+ FMOVD 16(R5), F1
+ WFMADB V0, V4, V3, V4
+ FMOVD 8(R5), F3
+ WFMADB V2, V1, V3, V1
+ RISBGZ $57, $60, $3, R1, R3
+ WFMADB V0, V4, V1, V0
+ MOVD $·exptexp<>+0(SB), R2
+ WORD $0x68432000 //ld %f4,0(%r3,%r2)
+ FMADD F4, F2, F2
+ SLD $48, R1, R2
+ WFMADB V2, V0, V4, V2
+ LDGR R2, F0
+ FMADD F0, F2, F0
+ FMOVD F0, ret+8(FP)
+ RET
+L16:
+ WFCEDBS V2, V2, V4
+ BVS LEXITTAGexp
+ WORD $0xED205000 //cdb %f2,.L33-.L22(%r5)
+ BYTE $0x00
+ BYTE $0x19
+ BLT L6
+ WFCEDBS V2, V0, V0
+ BVS L13
+ MOVD $·expxinf<>+0(SB), R1
+ FMOVD 0(R1), F0
+ FMOVD F0, ret+8(FP)
+ RET
+L20:
+ LCDBR F0, F2
+ BR L2
+L6:
+ MOVD $·expxaddexp<>+0(SB), R1
+ FMOVD 72(R5), F3
+ FMOVD 0(R1), F4
+ WFMSDB V0, V3, V4, V3
+ FMOVD 64(R5), F6
+ FADD F3, F4
+ FMOVD 56(R5), F5
+ WFMADB V4, V6, V0, V6
+ FMOVD 32(R5), F1
+ WFMADB V4, V5, V6, V4
+ FMOVD 40(R5), F5
+ FMUL F6, F6
+ WFMADB V4, V1, V5, V1
+ FMOVD 48(R5), F7
+ LGDR F3, R1
+ FMOVD 24(R5), F5
+ WFMADB V4, V7, V5, V7
+ FMOVD 16(R5), F5
+ WFMADB V6, V1, V7, V1
+ FMOVD 8(R5), F7
+ WFMADB V4, V5, V7, V5
+ RISBGZ $57, $60, $3, R1, R3
+ WFMADB V6, V1, V5, V6
+ MOVD $·exptexp<>+0(SB), R2
+ WFCHDBS V2, V0, V0
+ WORD $0x68132000 //ld %f1,0(%r3,%r2)
+ FMADD F1, F4, F4
+ MOVD $0x4086000000000000, R2
+ WFMADB V4, V6, V1, V4
+ BEQ L21
+ ADDW $0xF000, R1
+ RISBGN $0, $15, $48, R1, R2
+ LDGR R2, F0
+ FMADD F0, F4, F0
+ MOVD $·expx4ff<>+0(SB), R3
+ FMOVD 0(R3), F2
+ FMUL F2, F0
+ FMOVD F0, ret+8(FP)
+ RET
+L13:
+ FMOVD $0, F0
+ FMOVD F0, ret+8(FP)
+ RET
+L21:
+ ADDW $0x1000, R1
+ RISBGN $0, $15, $48, R1, R2
+ LDGR R2, F0
+ FMADD F0, F4, F0
+ MOVD $·expx2ff<>+0(SB), R3
+ FMOVD 0(R3), F2
+ FMUL F2, F0
+ FMOVD F0, ret+8(FP)
+ RET
+LEXITTAGexp:
+ FMOVD F0, ret+8(FP)
+ RET
diff --git a/go/src/math/expm1.go b/go/src/math/expm1.go
new file mode 100644
index 0000000000000000000000000000000000000000..f8e45d9becf2be550498dd58d2b3efb56cfd107d
--- /dev/null
+++ b/go/src/math/expm1.go
@@ -0,0 +1,244 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// The original C code, the long comment, and the constants
+// below are from FreeBSD's /usr/src/lib/msun/src/s_expm1.c
+// and came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+// expm1(x)
+// Returns exp(x)-1, the exponential of x minus 1.
+//
+// Method
+// 1. Argument reduction:
+// Given x, find r and integer k such that
+//
+// x = k*ln2 + r, |r| <= 0.5*ln2 ~ 0.34658
+//
+// Here a correction term c will be computed to compensate
+// the error in r when rounded to a floating-point number.
+//
+// 2. Approximating expm1(r) by a special rational function on
+// the interval [0,0.34658]:
+// Since
+// r*(exp(r)+1)/(exp(r)-1) = 2+ r**2/6 - r**4/360 + ...
+// we define R1(r*r) by
+// r*(exp(r)+1)/(exp(r)-1) = 2+ r**2/6 * R1(r*r)
+// That is,
+// R1(r**2) = 6/r *((exp(r)+1)/(exp(r)-1) - 2/r)
+// = 6/r * ( 1 + 2.0*(1/(exp(r)-1) - 1/r))
+// = 1 - r**2/60 + r**4/2520 - r**6/100800 + ...
+// We use a special Reme algorithm on [0,0.347] to generate
+// a polynomial of degree 5 in r*r to approximate R1. The
+// maximum error of this polynomial approximation is bounded
+// by 2**-61. In other words,
+// R1(z) ~ 1.0 + Q1*z + Q2*z**2 + Q3*z**3 + Q4*z**4 + Q5*z**5
+// where Q1 = -1.6666666666666567384E-2,
+// Q2 = 3.9682539681370365873E-4,
+// Q3 = -9.9206344733435987357E-6,
+// Q4 = 2.5051361420808517002E-7,
+// Q5 = -6.2843505682382617102E-9;
+// (where z=r*r, and the values of Q1 to Q5 are listed below)
+// with error bounded by
+// | 5 | -61
+// | 1.0+Q1*z+...+Q5*z - R1(z) | <= 2
+// | |
+//
+// expm1(r) = exp(r)-1 is then computed by the following
+// specific way which minimize the accumulation rounding error:
+// 2 3
+// r r [ 3 - (R1 + R1*r/2) ]
+// expm1(r) = r + --- + --- * [--------------------]
+// 2 2 [ 6 - r*(3 - R1*r/2) ]
+//
+// To compensate the error in the argument reduction, we use
+// expm1(r+c) = expm1(r) + c + expm1(r)*c
+// ~ expm1(r) + c + r*c
+// Thus c+r*c will be added in as the correction terms for
+// expm1(r+c). Now rearrange the term to avoid optimization
+// screw up:
+// ( 2 2 )
+// ({ ( r [ R1 - (3 - R1*r/2) ] ) } r )
+// expm1(r+c)~r - ({r*(--- * [--------------------]-c)-c} - --- )
+// ({ ( 2 [ 6 - r*(3 - R1*r/2) ] ) } 2 )
+// ( )
+//
+// = r - E
+// 3. Scale back to obtain expm1(x):
+// From step 1, we have
+// expm1(x) = either 2**k*[expm1(r)+1] - 1
+// = or 2**k*[expm1(r) + (1-2**-k)]
+// 4. Implementation notes:
+// (A). To save one multiplication, we scale the coefficient Qi
+// to Qi*2**i, and replace z by (x**2)/2.
+// (B). To achieve maximum accuracy, we compute expm1(x) by
+// (i) if x < -56*ln2, return -1.0, (raise inexact if x!=inf)
+// (ii) if k=0, return r-E
+// (iii) if k=-1, return 0.5*(r-E)-0.5
+// (iv) if k=1 if r < -0.25, return 2*((r+0.5)- E)
+// else return 1.0+2.0*(r-E);
+// (v) if (k<-2||k>56) return 2**k(1-(E-r)) - 1 (or exp(x)-1)
+// (vi) if k <= 20, return 2**k((1-2**-k)-(E-r)), else
+// (vii) return 2**k(1-((E+2**-k)-r))
+//
+// Special cases:
+// expm1(INF) is INF, expm1(NaN) is NaN;
+// expm1(-INF) is -1, and
+// for finite argument, only expm1(0)=0 is exact.
+//
+// Accuracy:
+// according to an error analysis, the error is always less than
+// 1 ulp (unit in the last place).
+//
+// Misc. info.
+// For IEEE double
+// if x > 7.09782712893383973096e+02 then expm1(x) overflow
+//
+// Constants:
+// The hexadecimal values are the intended ones for the following
+// constants. The decimal values may be used, provided that the
+// compiler will convert from decimal to binary accurately enough
+// to produce the hexadecimal values shown.
+//
+
+// Expm1 returns e**x - 1, the base-e exponential of x minus 1.
+// It is more accurate than [Exp](x) - 1 when x is near zero.
+//
+// Special cases are:
+//
+// Expm1(+Inf) = +Inf
+// Expm1(-Inf) = -1
+// Expm1(NaN) = NaN
+//
+// Very large values overflow to -1 or +Inf.
+func Expm1(x float64) float64 {
+ if haveArchExpm1 {
+ return archExpm1(x)
+ }
+ return expm1(x)
+}
+
+func expm1(x float64) float64 {
+ const (
+ Othreshold = 7.09782712893383973096e+02 // 0x40862E42FEFA39EF
+ Ln2X56 = 3.88162421113569373274e+01 // 0x4043687a9f1af2b1
+ Ln2HalfX3 = 1.03972077083991796413e+00 // 0x3ff0a2b23f3bab73
+ Ln2Half = 3.46573590279972654709e-01 // 0x3fd62e42fefa39ef
+ Ln2Hi = 6.93147180369123816490e-01 // 0x3fe62e42fee00000
+ Ln2Lo = 1.90821492927058770002e-10 // 0x3dea39ef35793c76
+ InvLn2 = 1.44269504088896338700e+00 // 0x3ff71547652b82fe
+ Tiny = 1.0 / (1 << 54) // 2**-54 = 0x3c90000000000000
+ // scaled coefficients related to expm1
+ Q1 = -3.33333333333331316428e-02 // 0xBFA11111111110F4
+ Q2 = 1.58730158725481460165e-03 // 0x3F5A01A019FE5585
+ Q3 = -7.93650757867487942473e-05 // 0xBF14CE199EAADBB7
+ Q4 = 4.00821782732936239552e-06 // 0x3ED0CFCA86E65239
+ Q5 = -2.01099218183624371326e-07 // 0xBE8AFDB76E09C32D
+ )
+
+ // special cases
+ switch {
+ case IsInf(x, 1) || IsNaN(x):
+ return x
+ case IsInf(x, -1):
+ return -1
+ }
+
+ absx := x
+ sign := false
+ if x < 0 {
+ absx = -absx
+ sign = true
+ }
+
+ // filter out huge argument
+ if absx >= Ln2X56 { // if |x| >= 56 * ln2
+ if sign {
+ return -1 // x < -56*ln2, return -1
+ }
+ if absx >= Othreshold { // if |x| >= 709.78...
+ return Inf(1)
+ }
+ }
+
+ // argument reduction
+ var c float64
+ var k int
+ if absx > Ln2Half { // if |x| > 0.5 * ln2
+ var hi, lo float64
+ if absx < Ln2HalfX3 { // and |x| < 1.5 * ln2
+ if !sign {
+ hi = x - Ln2Hi
+ lo = Ln2Lo
+ k = 1
+ } else {
+ hi = x + Ln2Hi
+ lo = -Ln2Lo
+ k = -1
+ }
+ } else {
+ if !sign {
+ k = int(InvLn2*x + 0.5)
+ } else {
+ k = int(InvLn2*x - 0.5)
+ }
+ t := float64(k)
+ hi = x - t*Ln2Hi // t * Ln2Hi is exact here
+ lo = t * Ln2Lo
+ }
+ x = hi - lo
+ c = (hi - x) - lo
+ } else if absx < Tiny { // when |x| < 2**-54, return x
+ return x
+ } else {
+ k = 0
+ }
+
+ // x is now in primary range
+ hfx := 0.5 * x
+ hxs := x * hfx
+ r1 := 1 + hxs*(Q1+hxs*(Q2+hxs*(Q3+hxs*(Q4+hxs*Q5))))
+ t := 3 - r1*hfx
+ e := hxs * ((r1 - t) / (6.0 - x*t))
+ if k == 0 {
+ return x - (x*e - hxs) // c is 0
+ }
+ e = (x*(e-c) - c)
+ e -= hxs
+ switch {
+ case k == -1:
+ return 0.5*(x-e) - 0.5
+ case k == 1:
+ if x < -0.25 {
+ return -2 * (e - (x + 0.5))
+ }
+ return 1 + 2*(x-e)
+ case k <= -2 || k > 56: // suffice to return exp(x)-1
+ y := 1 - (e - x)
+ y = Float64frombits(Float64bits(y) + uint64(k)<<52) // add k to y's exponent
+ return y - 1
+ }
+ if k < 20 {
+ t := Float64frombits(0x3ff0000000000000 - (0x20000000000000 >> uint(k))) // t=1-2**-k
+ y := t - (e - x)
+ y = Float64frombits(Float64bits(y) + uint64(k)<<52) // add k to y's exponent
+ return y
+ }
+ t = Float64frombits(uint64(0x3ff-k) << 52) // 2**-k
+ y := x - (e + t)
+ y++
+ y = Float64frombits(Float64bits(y) + uint64(k)<<52) // add k to y's exponent
+ return y
+}
diff --git a/go/src/math/expm1_s390x.s b/go/src/math/expm1_s390x.s
new file mode 100644
index 0000000000000000000000000000000000000000..c193edc7cb8794127d8c393ef2ebdfbe44b95380
--- /dev/null
+++ b/go/src/math/expm1_s390x.s
@@ -0,0 +1,194 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// Minimax polynomial approximation and other constants
+DATA ·expm1rodataL22<> + 0(SB)/8, $-1.0
+DATA ·expm1rodataL22<> + 8(SB)/8, $800.0E+00
+DATA ·expm1rodataL22<> + 16(SB)/8, $1.0
+DATA ·expm1rodataL22<> + 24(SB)/8, $-.231904681384629956E-16
+DATA ·expm1rodataL22<> + 32(SB)/8, $0.50000000000000029671E+00
+DATA ·expm1rodataL22<> + 40(SB)/8, $0.16666666666666676570E+00
+DATA ·expm1rodataL22<> + 48(SB)/8, $0.83333333323590973444E-02
+DATA ·expm1rodataL22<> + 56(SB)/8, $0.13889096526400683566E-02
+DATA ·expm1rodataL22<> + 64(SB)/8, $0.41666666661701152924E-01
+DATA ·expm1rodataL22<> + 72(SB)/8, $0.19841562053987360264E-03
+DATA ·expm1rodataL22<> + 80(SB)/8, $-.693147180559945286E+00
+DATA ·expm1rodataL22<> + 88(SB)/8, $0.144269504088896339E+01
+DATA ·expm1rodataL22<> + 96(SB)/8, $704.0E+00
+GLOBL ·expm1rodataL22<> + 0(SB), RODATA, $104
+
+DATA ·expm1xmone<> + 0(SB)/8, $0xbff0000000000000
+GLOBL ·expm1xmone<> + 0(SB), RODATA, $8
+DATA ·expm1xinf<> + 0(SB)/8, $0x7ff0000000000000
+GLOBL ·expm1xinf<> + 0(SB), RODATA, $8
+DATA ·expm1x4ff<> + 0(SB)/8, $0x4ff0000000000000
+GLOBL ·expm1x4ff<> + 0(SB), RODATA, $8
+DATA ·expm1x2ff<> + 0(SB)/8, $0x2ff0000000000000
+GLOBL ·expm1x2ff<> + 0(SB), RODATA, $8
+DATA ·expm1xaddexp<> + 0(SB)/8, $0xc2f0000100003ff0
+GLOBL ·expm1xaddexp<> + 0(SB), RODATA, $8
+
+// Log multipliers table
+DATA ·expm1tab<> + 0(SB)/8, $0.0
+DATA ·expm1tab<> + 8(SB)/8, $-.171540871271399150E-01
+DATA ·expm1tab<> + 16(SB)/8, $-.306597931864376363E-01
+DATA ·expm1tab<> + 24(SB)/8, $-.410200970469965021E-01
+DATA ·expm1tab<> + 32(SB)/8, $-.486343079978231466E-01
+DATA ·expm1tab<> + 40(SB)/8, $-.538226193725835820E-01
+DATA ·expm1tab<> + 48(SB)/8, $-.568439602538111520E-01
+DATA ·expm1tab<> + 56(SB)/8, $-.579091847395528847E-01
+DATA ·expm1tab<> + 64(SB)/8, $-.571909584179366341E-01
+DATA ·expm1tab<> + 72(SB)/8, $-.548312665987204407E-01
+DATA ·expm1tab<> + 80(SB)/8, $-.509471843643441085E-01
+DATA ·expm1tab<> + 88(SB)/8, $-.456353588448863359E-01
+DATA ·expm1tab<> + 96(SB)/8, $-.389755254243262365E-01
+DATA ·expm1tab<> + 104(SB)/8, $-.310332908285244231E-01
+DATA ·expm1tab<> + 112(SB)/8, $-.218623539150173528E-01
+DATA ·expm1tab<> + 120(SB)/8, $-.115062908917949451E-01
+GLOBL ·expm1tab<> + 0(SB), RODATA, $128
+
+// Expm1 returns e**x - 1, the base-e exponential of x minus 1.
+// It is more accurate than Exp(x) - 1 when x is near zero.
+//
+// Special cases are:
+// Expm1(+Inf) = +Inf
+// Expm1(-Inf) = -1
+// Expm1(NaN) = NaN
+// Very large values overflow to -1 or +Inf.
+// The algorithm used is minimax polynomial approximation using a table of
+// polynomial coefficients determined with a Remez exchange algorithm.
+
+TEXT ·expm1Asm(SB), NOSPLIT, $0-16
+ FMOVD x+0(FP), F0
+ MOVD $·expm1rodataL22<>+0(SB), R5
+ LTDBR F0, F0
+ BLTU L20
+ FMOVD F0, F2
+L2:
+ WORD $0xED205060 //cdb %f2,.L23-.L22(%r5)
+ BYTE $0x00
+ BYTE $0x19
+ BGE L16
+ BVS L16
+ WFCEDBS V2, V2, V2
+ BVS LEXITTAGexpm1
+ MOVD $·expm1xaddexp<>+0(SB), R1
+ FMOVD 88(R5), F1
+ FMOVD 0(R1), F2
+ WFMSDB V0, V1, V2, V1
+ FMOVD 80(R5), F6
+ WFADB V1, V2, V4
+ FMOVD 72(R5), F2
+ FMADD F6, F4, F0
+ FMOVD 64(R5), F3
+ FMOVD 56(R5), F6
+ FMOVD 48(R5), F5
+ FMADD F2, F0, F6
+ WFMADB V0, V5, V3, V5
+ WFMDB V0, V0, V2
+ LGDR F1, R1
+ WFMADB V6, V2, V5, V6
+ FMOVD 40(R5), F3
+ FMOVD 32(R5), F5
+ WFMADB V0, V3, V5, V3
+ FMOVD 24(R5), F5
+ WFMADB V2, V6, V3, V2
+ FMADD F5, F4, F0
+ FMOVD 16(R5), F6
+ WFMADB V0, V2, V6, V2
+ RISBGZ $57, $60, $3, R1, R3
+ LCDBR F2, F2
+ MOVD $·expm1tab<>+0(SB), R2
+ WORD $0x68432000 //ld %f4,0(%r3,%r2)
+ FMADD F4, F0, F0
+ SLD $48, R1, R2
+ WFMSDB V2, V0, V4, V0
+ LDGR R2, F4
+ LCDBR F0, F0
+ FSUB F4, F6
+ WFMSDB V0, V4, V6, V0
+ FMOVD F0, ret+8(FP)
+ RET
+L16:
+ WFCEDBS V2, V2, V4
+ BVS LEXITTAGexpm1
+ WORD $0xED205008 //cdb %f2,.L34-.L22(%r5)
+ BYTE $0x00
+ BYTE $0x19
+ BLT L6
+ WFCEDBS V2, V0, V0
+ BVS L7
+ MOVD $·expm1xinf<>+0(SB), R1
+ FMOVD 0(R1), F0
+ FMOVD F0, ret+8(FP)
+ RET
+L20:
+ LCDBR F0, F2
+ BR L2
+L6:
+ MOVD $·expm1xaddexp<>+0(SB), R1
+ FMOVD 88(R5), F5
+ FMOVD 0(R1), F4
+ WFMSDB V0, V5, V4, V5
+ FMOVD 80(R5), F3
+ WFADB V5, V4, V1
+ VLEG $0, 48(R5), V16
+ WFMADB V1, V3, V0, V3
+ FMOVD 56(R5), F4
+ FMOVD 64(R5), F7
+ FMOVD 72(R5), F6
+ WFMADB V3, V16, V7, V16
+ WFMADB V3, V6, V4, V6
+ WFMDB V3, V3, V4
+ MOVD $·expm1tab<>+0(SB), R2
+ WFMADB V6, V4, V16, V6
+ VLEG $0, 32(R5), V16
+ FMOVD 40(R5), F7
+ WFMADB V3, V7, V16, V7
+ VLEG $0, 24(R5), V16
+ WFMADB V4, V6, V7, V4
+ WFMADB V1, V16, V3, V1
+ FMOVD 16(R5), F6
+ FMADD F4, F1, F6
+ LGDR F5, R1
+ LCDBR F6, F6
+ RISBGZ $57, $60, $3, R1, R3
+ WORD $0x68432000 //ld %f4,0(%r3,%r2)
+ FMADD F4, F1, F1
+ MOVD $0x4086000000000000, R2
+ FMSUB F1, F6, F4
+ LCDBR F4, F4
+ WFCHDBS V2, V0, V0
+ BEQ L21
+ ADDW $0xF000, R1
+ RISBGN $0, $15, $48, R1, R2
+ LDGR R2, F0
+ FMADD F0, F4, F0
+ MOVD $·expm1x4ff<>+0(SB), R3
+ FMOVD 0(R5), F4
+ FMOVD 0(R3), F2
+ WFMADB V2, V0, V4, V0
+ FMOVD F0, ret+8(FP)
+ RET
+L7:
+ MOVD $·expm1xmone<>+0(SB), R1
+ FMOVD 0(R1), F0
+ FMOVD F0, ret+8(FP)
+ RET
+L21:
+ ADDW $0x1000, R1
+ RISBGN $0, $15, $48, R1, R2
+ LDGR R2, F0
+ FMADD F0, F4, F0
+ MOVD $·expm1x2ff<>+0(SB), R3
+ FMOVD 0(R5), F4
+ FMOVD 0(R3), F2
+ WFMADB V2, V0, V4, V0
+ FMOVD F0, ret+8(FP)
+ RET
+LEXITTAGexpm1:
+ FMOVD F0, ret+8(FP)
+ RET
diff --git a/go/src/math/export_s390x_test.go b/go/src/math/export_s390x_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..827bf1c8f60f3846d72836782a6a1d968e076252
--- /dev/null
+++ b/go/src/math/export_s390x_test.go
@@ -0,0 +1,31 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Export internal functions and variable for testing.
+var Log10NoVec = log10
+var CosNoVec = cos
+var CoshNoVec = cosh
+var SinNoVec = sin
+var SinhNoVec = sinh
+var TanhNoVec = tanh
+var Log1pNovec = log1p
+var AtanhNovec = atanh
+var AcosNovec = acos
+var AcoshNovec = acosh
+var AsinNovec = asin
+var AsinhNovec = asinh
+var ErfNovec = erf
+var ErfcNovec = erfc
+var AtanNovec = atan
+var Atan2Novec = atan2
+var CbrtNovec = cbrt
+var LogNovec = log
+var TanNovec = tan
+var ExpNovec = exp
+var Expm1Novec = expm1
+var PowNovec = pow
+var HypotNovec = hypot
+var HasVX = hasVX
diff --git a/go/src/math/export_test.go b/go/src/math/export_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..53d9205b9d1693d745e12695cb3d05fe576aef32
--- /dev/null
+++ b/go/src/math/export_test.go
@@ -0,0 +1,14 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Export internal functions for testing.
+var ExpGo = exp
+var Exp2Go = exp2
+var HypotGo = hypot
+var SqrtGo = sqrt
+var TrigReduce = trigReduce
+
+const ReduceThreshold = reduceThreshold
diff --git a/go/src/math/floor.go b/go/src/math/floor.go
new file mode 100644
index 0000000000000000000000000000000000000000..20a764112478c8713157ea63703dab451f367873
--- /dev/null
+++ b/go/src/math/floor.go
@@ -0,0 +1,158 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Floor returns the greatest integer value less than or equal to x.
+//
+// Special cases are:
+//
+// Floor(±0) = ±0
+// Floor(±Inf) = ±Inf
+// Floor(NaN) = NaN
+func Floor(x float64) float64 {
+ if haveArchFloor {
+ return archFloor(x)
+ }
+ return floor(x)
+}
+
+func floor(x float64) float64 {
+ if x == 0 || IsNaN(x) || IsInf(x, 0) {
+ return x
+ }
+ if x < 0 {
+ d, fract := Modf(-x)
+ if fract != 0.0 {
+ d = d + 1
+ }
+ return -d
+ }
+ d, _ := Modf(x)
+ return d
+}
+
+// Ceil returns the least integer value greater than or equal to x.
+//
+// Special cases are:
+//
+// Ceil(±0) = ±0
+// Ceil(±Inf) = ±Inf
+// Ceil(NaN) = NaN
+func Ceil(x float64) float64 {
+ if haveArchCeil {
+ return archCeil(x)
+ }
+ return ceil(x)
+}
+
+func ceil(x float64) float64 {
+ return -Floor(-x)
+}
+
+// Trunc returns the integer value of x.
+//
+// Special cases are:
+//
+// Trunc(±0) = ±0
+// Trunc(±Inf) = ±Inf
+// Trunc(NaN) = NaN
+func Trunc(x float64) float64 {
+ if haveArchTrunc {
+ return archTrunc(x)
+ }
+ return trunc(x)
+}
+
+func trunc(x float64) float64 {
+ if Abs(x) < 1 {
+ return Copysign(0, x)
+ }
+
+ b := Float64bits(x)
+ e := uint(b>>shift)&mask - bias
+
+ // Keep the top 12+e bits, the integer part; clear the rest.
+ if e < 64-12 {
+ b &^= 1<<(64-12-e) - 1
+ }
+ return Float64frombits(b)
+}
+
+// Round returns the nearest integer, rounding half away from zero.
+//
+// Special cases are:
+//
+// Round(±0) = ±0
+// Round(±Inf) = ±Inf
+// Round(NaN) = NaN
+func Round(x float64) float64 {
+ // Round is a faster implementation of:
+ //
+ // func Round(x float64) float64 {
+ // t := Trunc(x)
+ // if Abs(x-t) >= 0.5 {
+ // return t + Copysign(1, x)
+ // }
+ // return t
+ // }
+ bits := Float64bits(x)
+ e := uint(bits>>shift) & mask
+ if e < bias {
+ // Round abs(x) < 1 including denormals.
+ bits &= signMask // +-0
+ if e == bias-1 {
+ bits |= uvone // +-1
+ }
+ } else if e < bias+shift {
+ // Round any abs(x) >= 1 containing a fractional component [0,1).
+ //
+ // Numbers with larger exponents are returned unchanged since they
+ // must be either an integer, infinity, or NaN.
+ const half = 1 << (shift - 1)
+ e -= bias
+ bits += half >> e
+ bits &^= fracMask >> e
+ }
+ return Float64frombits(bits)
+}
+
+// RoundToEven returns the nearest integer, rounding ties to even.
+//
+// Special cases are:
+//
+// RoundToEven(±0) = ±0
+// RoundToEven(±Inf) = ±Inf
+// RoundToEven(NaN) = NaN
+func RoundToEven(x float64) float64 {
+ // RoundToEven is a faster implementation of:
+ //
+ // func RoundToEven(x float64) float64 {
+ // t := math.Trunc(x)
+ // odd := math.Remainder(t, 2) != 0
+ // if d := math.Abs(x - t); d > 0.5 || (d == 0.5 && odd) {
+ // return t + math.Copysign(1, x)
+ // }
+ // return t
+ // }
+ bits := Float64bits(x)
+ e := uint(bits>>shift) & mask
+ if e >= bias {
+ // Round abs(x) >= 1.
+ // - Large numbers without fractional components, infinity, and NaN are unchanged.
+ // - Add 0.499.. or 0.5 before truncating depending on whether the truncated
+ // number is even or odd (respectively).
+ const halfMinusULP = (1 << (shift - 1)) - 1
+ e -= bias
+ bits += (halfMinusULP + (bits>>(shift-e))&1) >> e
+ bits &^= fracMask >> e
+ } else if e == bias-1 && bits&fracMask != 0 {
+ // Round 0.5 < abs(x) < 1.
+ bits = bits&signMask | uvone // +-1
+ } else {
+ // Round abs(x) <= 0.5 including denormals.
+ bits &= signMask // +-0
+ }
+ return Float64frombits(bits)
+}
diff --git a/go/src/math/floor_386.s b/go/src/math/floor_386.s
new file mode 100644
index 0000000000000000000000000000000000000000..1990cb0c8c00d56c2dffa7e9eab5613afd95f2b4
--- /dev/null
+++ b/go/src/math/floor_386.s
@@ -0,0 +1,46 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// func archCeil(x float64) float64
+TEXT ·archCeil(SB),NOSPLIT,$0
+ FMOVD x+0(FP), F0 // F0=x
+ FSTCW -2(SP) // save old Control Word
+ MOVW -2(SP), AX
+ ANDW $0xf3ff, AX
+ ORW $0x0800, AX // Rounding Control set to +Inf
+ MOVW AX, -4(SP) // store new Control Word
+ FLDCW -4(SP) // load new Control Word
+ FRNDINT // F0=Ceil(x)
+ FLDCW -2(SP) // load old Control Word
+ FMOVDP F0, ret+8(FP)
+ RET
+
+// func archFloor(x float64) float64
+TEXT ·archFloor(SB),NOSPLIT,$0
+ FMOVD x+0(FP), F0 // F0=x
+ FSTCW -2(SP) // save old Control Word
+ MOVW -2(SP), AX
+ ANDW $0xf3ff, AX
+ ORW $0x0400, AX // Rounding Control set to -Inf
+ MOVW AX, -4(SP) // store new Control Word
+ FLDCW -4(SP) // load new Control Word
+ FRNDINT // F0=Floor(x)
+ FLDCW -2(SP) // load old Control Word
+ FMOVDP F0, ret+8(FP)
+ RET
+
+// func archTrunc(x float64) float64
+TEXT ·archTrunc(SB),NOSPLIT,$0
+ FMOVD x+0(FP), F0 // F0=x
+ FSTCW -2(SP) // save old Control Word
+ MOVW -2(SP), AX
+ ORW $0x0c00, AX // Rounding Control set to truncate
+ MOVW AX, -4(SP) // store new Control Word
+ FLDCW -4(SP) // load new Control Word
+ FRNDINT // F0=Trunc(x)
+ FLDCW -2(SP) // load old Control Word
+ FMOVDP F0, ret+8(FP)
+ RET
diff --git a/go/src/math/floor_amd64.s b/go/src/math/floor_amd64.s
new file mode 100644
index 0000000000000000000000000000000000000000..088049958ab4c7bf392bc119bcb710c48f7b0422
--- /dev/null
+++ b/go/src/math/floor_amd64.s
@@ -0,0 +1,76 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+#define Big 0x4330000000000000 // 2**52
+
+// func archFloor(x float64) float64
+TEXT ·archFloor(SB),NOSPLIT,$0
+ MOVQ x+0(FP), AX
+ MOVQ $~(1<<63), DX // sign bit mask
+ ANDQ AX,DX // DX = |x|
+ SUBQ $1,DX
+ MOVQ $(Big - 1), CX // if |x| >= 2**52-1 or IsNaN(x) or |x| == 0, return x
+ CMPQ DX,CX
+ JAE isBig_floor
+ MOVQ AX, X0 // X0 = x
+ CVTTSD2SQ X0, AX
+ CVTSQ2SD AX, X1 // X1 = float(int(x))
+ CMPSD X1, X0, 1 // compare LT; X0 = 0xffffffffffffffff or 0
+ MOVSD $(-1.0), X2
+ ANDPD X2, X0 // if x < float(int(x)) {X0 = -1} else {X0 = 0}
+ ADDSD X1, X0
+ MOVSD X0, ret+8(FP)
+ RET
+isBig_floor:
+ MOVQ AX, ret+8(FP) // return x
+ RET
+
+// func archCeil(x float64) float64
+TEXT ·archCeil(SB),NOSPLIT,$0
+ MOVQ x+0(FP), AX
+ MOVQ $~(1<<63), DX // sign bit mask
+ MOVQ AX, BX // BX = copy of x
+ ANDQ DX, BX // BX = |x|
+ MOVQ $Big, CX // if |x| >= 2**52 or IsNaN(x), return x
+ CMPQ BX, CX
+ JAE isBig_ceil
+ MOVQ AX, X0 // X0 = x
+ MOVQ DX, X2 // X2 = sign bit mask
+ CVTTSD2SQ X0, AX
+ ANDNPD X0, X2 // X2 = sign
+ CVTSQ2SD AX, X1 // X1 = float(int(x))
+ CMPSD X1, X0, 2 // compare LE; X0 = 0xffffffffffffffff or 0
+ ORPD X2, X1 // if X1 = 0.0, incorporate sign
+ MOVSD $1.0, X3
+ ANDNPD X3, X0
+ ORPD X2, X0 // if float(int(x)) <= x {X0 = 1} else {X0 = -0}
+ ADDSD X1, X0
+ MOVSD X0, ret+8(FP)
+ RET
+isBig_ceil:
+ MOVQ AX, ret+8(FP)
+ RET
+
+// func archTrunc(x float64) float64
+TEXT ·archTrunc(SB),NOSPLIT,$0
+ MOVQ x+0(FP), AX
+ MOVQ $~(1<<63), DX // sign bit mask
+ MOVQ AX, BX // BX = copy of x
+ ANDQ DX, BX // BX = |x|
+ MOVQ $Big, CX // if |x| >= 2**52 or IsNaN(x), return x
+ CMPQ BX, CX
+ JAE isBig_trunc
+ MOVQ AX, X0
+ MOVQ DX, X2 // X2 = sign bit mask
+ CVTTSD2SQ X0, AX
+ ANDNPD X0, X2 // X2 = sign
+ CVTSQ2SD AX, X0 // X0 = float(int(x))
+ ORPD X2, X0 // if X0 = 0.0, incorporate sign
+ MOVSD X0, ret+8(FP)
+ RET
+isBig_trunc:
+ MOVQ AX, ret+8(FP) // return x
+ RET
diff --git a/go/src/math/floor_arm64.s b/go/src/math/floor_arm64.s
new file mode 100644
index 0000000000000000000000000000000000000000..d9c5df7b2472dbff1566042612a18e5181871718
--- /dev/null
+++ b/go/src/math/floor_arm64.s
@@ -0,0 +1,26 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// func archFloor(x float64) float64
+TEXT ·archFloor(SB),NOSPLIT,$0
+ FMOVD x+0(FP), F0
+ FRINTMD F0, F0
+ FMOVD F0, ret+8(FP)
+ RET
+
+// func archCeil(x float64) float64
+TEXT ·archCeil(SB),NOSPLIT,$0
+ FMOVD x+0(FP), F0
+ FRINTPD F0, F0
+ FMOVD F0, ret+8(FP)
+ RET
+
+// func archTrunc(x float64) float64
+TEXT ·archTrunc(SB),NOSPLIT,$0
+ FMOVD x+0(FP), F0
+ FRINTZD F0, F0
+ FMOVD F0, ret+8(FP)
+ RET
diff --git a/go/src/math/floor_asm.go b/go/src/math/floor_asm.go
new file mode 100644
index 0000000000000000000000000000000000000000..1b06b8def9c65095e15373f35933499542b283a9
--- /dev/null
+++ b/go/src/math/floor_asm.go
@@ -0,0 +1,19 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build 386 || amd64 || arm64 || loong64 || ppc64 || ppc64le || riscv64 || s390x || wasm
+
+package math
+
+const haveArchFloor = true
+
+func archFloor(x float64) float64
+
+const haveArchCeil = true
+
+func archCeil(x float64) float64
+
+const haveArchTrunc = true
+
+func archTrunc(x float64) float64
diff --git a/go/src/math/floor_loong64.s b/go/src/math/floor_loong64.s
new file mode 100644
index 0000000000000000000000000000000000000000..0df7deee60588d8ef76696da393222e4fa3605f1
--- /dev/null
+++ b/go/src/math/floor_loong64.s
@@ -0,0 +1,41 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+//
+// derived from math/floor_riscv64.s
+
+#include "textflag.h"
+
+#define ROUNDFN(NAME, FUNC) \
+TEXT NAME(SB),NOSPLIT,$0; \
+ MOVD x+0(FP), F0; \
+ MOVV F0, R11; \
+ /* 1023: bias of exponent, [-2^53, 2^53]: exactly integer represent range */; \
+ MOVV $1023+53, R12; \
+ /* Drop all fraction bits */; \
+ SRLV $52, R11, R11; \
+ /* Remove sign bit */; \
+ AND $0x7FF, R11, R11; \
+ BLTU R12, R11, isExtremum; \
+normal:; \
+ FUNC F0, F2; \
+ MOVV F2, R10; \
+ BEQ R10, R0, is0; \
+ FFINTDV F2, F0; \
+/* Return either input is +-Inf, NaN(0x7FF) or out of precision limitation */; \
+isExtremum:; \
+ MOVD F0, ret+8(FP); \
+ RET; \
+is0:; \
+ FCOPYSGD F0, F2, F2; \
+ MOVD F2, ret+8(FP); \
+ RET
+
+// func archFloor(x float64) float64
+ROUNDFN(·archFloor, FTINTRMVD)
+
+// func archCeil(x float64) float64
+ROUNDFN(·archCeil, FTINTRPVD)
+
+// func archTrunc(x float64) float64
+ROUNDFN(·archTrunc, FTINTRZVD)
diff --git a/go/src/math/floor_noasm.go b/go/src/math/floor_noasm.go
new file mode 100644
index 0000000000000000000000000000000000000000..34bd292f0e7751db536d61efca8b81230bc98416
--- /dev/null
+++ b/go/src/math/floor_noasm.go
@@ -0,0 +1,25 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !386 && !amd64 && !arm64 && !loong64 && !ppc64 && !ppc64le && !riscv64 && !s390x && !wasm
+
+package math
+
+const haveArchFloor = false
+
+func archFloor(x float64) float64 {
+ panic("not implemented")
+}
+
+const haveArchCeil = false
+
+func archCeil(x float64) float64 {
+ panic("not implemented")
+}
+
+const haveArchTrunc = false
+
+func archTrunc(x float64) float64 {
+ panic("not implemented")
+}
diff --git a/go/src/math/floor_ppc64x.s b/go/src/math/floor_ppc64x.s
new file mode 100644
index 0000000000000000000000000000000000000000..e9c5d49f4a5aaf6dfd2a438ad2ec98acc8e5cfc9
--- /dev/null
+++ b/go/src/math/floor_ppc64x.s
@@ -0,0 +1,25 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build ppc64 || ppc64le
+
+#include "textflag.h"
+
+TEXT ·archFloor(SB),NOSPLIT,$0
+ FMOVD x+0(FP), F0
+ FRIM F0, F0
+ FMOVD F0, ret+8(FP)
+ RET
+
+TEXT ·archCeil(SB),NOSPLIT,$0
+ FMOVD x+0(FP), F0
+ FRIP F0, F0
+ FMOVD F0, ret+8(FP)
+ RET
+
+TEXT ·archTrunc(SB),NOSPLIT,$0
+ FMOVD x+0(FP), F0
+ FRIZ F0, F0
+ FMOVD F0, ret+8(FP)
+ RET
diff --git a/go/src/math/floor_riscv64.s b/go/src/math/floor_riscv64.s
new file mode 100644
index 0000000000000000000000000000000000000000..d9fe0ed8e2828ac860448943c3fca6065baf17e3
--- /dev/null
+++ b/go/src/math/floor_riscv64.s
@@ -0,0 +1,48 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// RISC-V offered floating-point (FP) rounding by FP conversion instructions (FCVT)
+// with rounding mode field.
+// As Go spec expects FP rounding result in FP, we have to use FCVT integer
+// back to FP (fp -> int -> fp).
+// RISC-V only set Inexact flag during invalid FP-integer conversion without changing any data,
+// on the other hand, RISC-V sets out of integer represent range yet valid FP into NaN.
+// When it comes to integer-FP conversion, invalid FP like NaN, +-Inf will be
+// converted into the closest valid FP, for example:
+//
+// `Floor(-Inf) -> int64(0x7fffffffffffffff) -> float64(9.22e+18)`
+// `Floor(18446744073709549568.0) -> int64(0x7fffffffffffffff) -> float64(9.22e+18)`
+//
+// This ISA conversion limitation requires we skip all invalid or out of range FP
+// before any normal rounding operations.
+
+#define ROUNDFN(NAME, MODE) \
+TEXT NAME(SB),NOSPLIT,$0; \
+ MOVD x+0(FP), F10; \
+ FMVXD F10, X10; \
+ /* Drop all fraction bits */;\
+ SRL $52, X10, X12; \
+ /* Remove sign bit */; \
+ AND $0x7FF, X12, X12;\
+ /* Return either input is +-Inf, NaN(0x7FF) or out of precision limitation */;\
+ /* 1023: bias of exponent, [-2^53, 2^53]: exactly integer represent range */;\
+ MOV $1023+53, X11; \
+ BLTU X11, X12, 4(PC);\
+ FCVTLD.MODE F10, X11; \
+ FCVTDL X11, F11; \
+ /* RISC-V rounds negative values to +0, restore original sign */;\
+ FSGNJD F10, F11, F10; \
+ MOVD F10, ret+8(FP); \
+ RET
+
+// func archFloor(x float64) float64
+ROUNDFN(·archFloor, RDN)
+
+// func archCeil(x float64) float64
+ROUNDFN(·archCeil, RUP)
+
+// func archTrunc(x float64) float64
+ROUNDFN(·archTrunc, RTZ)
diff --git a/go/src/math/floor_s390x.s b/go/src/math/floor_s390x.s
new file mode 100644
index 0000000000000000000000000000000000000000..b5dd462e526926bfb6d61911a898c37907f05c25
--- /dev/null
+++ b/go/src/math/floor_s390x.s
@@ -0,0 +1,26 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// func archFloor(x float64) float64
+TEXT ·archFloor(SB),NOSPLIT,$0
+ FMOVD x+0(FP), F0
+ FIDBR $7, F0, F0
+ FMOVD F0, ret+8(FP)
+ RET
+
+// func archCeil(x float64) float64
+TEXT ·archCeil(SB),NOSPLIT,$0
+ FMOVD x+0(FP), F0
+ FIDBR $6, F0, F0
+ FMOVD F0, ret+8(FP)
+ RET
+
+// func archTrunc(x float64) float64
+TEXT ·archTrunc(SB),NOSPLIT,$0
+ FMOVD x+0(FP), F0
+ FIDBR $5, F0, F0
+ FMOVD F0, ret+8(FP)
+ RET
diff --git a/go/src/math/floor_wasm.s b/go/src/math/floor_wasm.s
new file mode 100644
index 0000000000000000000000000000000000000000..3751471574610c5c2c85793b7c8a01f77ef89ffc
--- /dev/null
+++ b/go/src/math/floor_wasm.s
@@ -0,0 +1,26 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+TEXT ·archFloor(SB),NOSPLIT,$0
+ Get SP
+ F64Load x+0(FP)
+ F64Floor
+ F64Store ret+8(FP)
+ RET
+
+TEXT ·archCeil(SB),NOSPLIT,$0
+ Get SP
+ F64Load x+0(FP)
+ F64Ceil
+ F64Store ret+8(FP)
+ RET
+
+TEXT ·archTrunc(SB),NOSPLIT,$0
+ Get SP
+ F64Load x+0(FP)
+ F64Trunc
+ F64Store ret+8(FP)
+ RET
diff --git a/go/src/math/fma.go b/go/src/math/fma.go
new file mode 100644
index 0000000000000000000000000000000000000000..c806b914dab5b60cced29e1e284db32177747a83
--- /dev/null
+++ b/go/src/math/fma.go
@@ -0,0 +1,182 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+import "math/bits"
+
+func zero(x uint64) uint64 {
+ if x == 0 {
+ return 1
+ }
+ return 0
+ // branchless:
+ // return ((x>>1 | x&1) - 1) >> 63
+}
+
+func nonzero(x uint64) uint64 {
+ if x != 0 {
+ return 1
+ }
+ return 0
+ // branchless:
+ // return 1 - ((x>>1|x&1)-1)>>63
+}
+
+func shl(u1, u2 uint64, n uint) (r1, r2 uint64) {
+ r1 = u1<>(64-n) | u2<<(n-64)
+ r2 = u2 << n
+ return
+}
+
+func shr(u1, u2 uint64, n uint) (r1, r2 uint64) {
+ r2 = u2>>n | u1<<(64-n) | u1>>(n-64)
+ r1 = u1 >> n
+ return
+}
+
+// shrcompress compresses the bottom n+1 bits of the two-word
+// value into a single bit. the result is equal to the value
+// shifted to the right by n, except the result's 0th bit is
+// set to the bitwise OR of the bottom n+1 bits.
+func shrcompress(u1, u2 uint64, n uint) (r1, r2 uint64) {
+ // TODO: Performance here is really sensitive to the
+ // order/placement of these branches. n == 0 is common
+ // enough to be in the fast path. Perhaps more measurement
+ // needs to be done to find the optimal order/placement?
+ switch {
+ case n == 0:
+ return u1, u2
+ case n == 64:
+ return 0, u1 | nonzero(u2)
+ case n >= 128:
+ return 0, nonzero(u1 | u2)
+ case n < 64:
+ r1, r2 = shr(u1, u2, n)
+ r2 |= nonzero(u2 & (1<> 63)
+ exp = int32(b>>52) & mask
+ mantissa = b & fracMask
+
+ if exp == 0 {
+ // Normalize value if subnormal.
+ shift := uint(bits.LeadingZeros64(mantissa) - 11)
+ mantissa <<= shift
+ exp = 1 - int32(shift)
+ } else {
+ // Add implicit 1 bit
+ mantissa |= 1 << 52
+ }
+ return
+}
+
+// FMA returns x * y + z, computed with only one rounding.
+// (That is, FMA returns the fused multiply-add of x, y, and z.)
+func FMA(x, y, z float64) float64 {
+ bx, by, bz := Float64bits(x), Float64bits(y), Float64bits(z)
+
+ // Inf or NaN or zero involved. At most one rounding will occur.
+ if x == 0.0 || y == 0.0 || bx&uvinf == uvinf || by&uvinf == uvinf {
+ return x*y + z
+ }
+ // Handle z == 0.0 separately.
+ // Adding zero usually does not change the original value.
+ // However, there is an exception with negative zero. (e.g. (-0) + (+0) = (+0))
+ // This applies when x * y is negative and underflows.
+ if z == 0.0 {
+ return x * y
+ }
+ // Handle non-finite z separately. Evaluating x*y+z where
+ // x and y are finite, but z is infinite, should always result in z.
+ if bz&uvinf == uvinf {
+ return z
+ }
+
+ // Inputs are (sub)normal.
+ // Split x, y, z into sign, exponent, mantissa.
+ xs, xe, xm := split(bx)
+ ys, ye, ym := split(by)
+ zs, ze, zm := split(bz)
+
+ // Compute product p = x*y as sign, exponent, two-word mantissa.
+ // Start with exponent. "is normal" bit isn't subtracted yet.
+ pe := xe + ye - bias + 1
+
+ // pm1:pm2 is the double-word mantissa for the product p.
+ // Shift left to leave top bit in product. Effectively
+ // shifts the 106-bit product to the left by 21.
+ pm1, pm2 := bits.Mul64(xm<<10, ym<<11)
+ zm1, zm2 := zm<<10, uint64(0)
+ ps := xs ^ ys // product sign
+
+ // normalize to 62nd bit
+ is62zero := uint((^pm1 >> 62) & 1)
+ pm1, pm2 = shl(pm1, pm2, is62zero)
+ pe -= int32(is62zero)
+
+ // Swap addition operands so |p| >= |z|
+ if pe < ze || pe == ze && pm1 < zm1 {
+ ps, pe, pm1, pm2, zs, ze, zm1, zm2 = zs, ze, zm1, zm2, ps, pe, pm1, pm2
+ }
+
+ // Special case: if p == -z the result is always +0 since neither operand is zero.
+ if ps != zs && pe == ze && pm1 == zm1 && pm2 == zm2 {
+ return 0
+ }
+
+ // Align significands
+ zm1, zm2 = shrcompress(zm1, zm2, uint(pe-ze))
+
+ // Compute resulting significands, normalizing if necessary.
+ var m, c uint64
+ if ps == zs {
+ // Adding (pm1:pm2) + (zm1:zm2)
+ pm2, c = bits.Add64(pm2, zm2, 0)
+ pm1, _ = bits.Add64(pm1, zm1, c)
+ pe -= int32(^pm1 >> 63)
+ pm1, m = shrcompress(pm1, pm2, uint(64+pm1>>63))
+ } else {
+ // Subtracting (pm1:pm2) - (zm1:zm2)
+ // TODO: should we special-case cancellation?
+ pm2, c = bits.Sub64(pm2, zm2, 0)
+ pm1, _ = bits.Sub64(pm1, zm1, c)
+ nz := lz(pm1, pm2)
+ pe -= nz
+ m, pm2 = shl(pm1, pm2, uint(nz-1))
+ m |= nonzero(pm2)
+ }
+
+ // Round and break ties to even
+ if pe > 1022+bias || pe == 1022+bias && (m+1<<9)>>63 == 1 {
+ // rounded value overflows exponent range
+ return Float64frombits(uint64(ps)<<63 | uvinf)
+ }
+ if pe < 0 {
+ n := uint(-pe)
+ m = m>>n | nonzero(m&(1<> 10) & ^zero((m&(1<<10-1))^1<<9)
+ pe &= -int32(nonzero(m))
+ return Float64frombits(uint64(ps)<<63 + uint64(pe)<<52 + m)
+}
diff --git a/go/src/math/frexp.go b/go/src/math/frexp.go
new file mode 100644
index 0000000000000000000000000000000000000000..e194947e646af437a251de11271f5635dbebcde7
--- /dev/null
+++ b/go/src/math/frexp.go
@@ -0,0 +1,39 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Frexp breaks f into a normalized fraction
+// and an integral power of two.
+// It returns frac and exp satisfying f == frac × 2**exp,
+// with the absolute value of frac in the interval [½, 1).
+//
+// Special cases are:
+//
+// Frexp(±0) = ±0, 0
+// Frexp(±Inf) = ±Inf, 0
+// Frexp(NaN) = NaN, 0
+func Frexp(f float64) (frac float64, exp int) {
+ if haveArchFrexp {
+ return archFrexp(f)
+ }
+ return frexp(f)
+}
+
+func frexp(f float64) (frac float64, exp int) {
+ // special cases
+ switch {
+ case f == 0:
+ return f, 0 // correctly return -0
+ case IsInf(f, 0) || IsNaN(f):
+ return f, 0
+ }
+ f, exp = normalize(f)
+ x := Float64bits(f)
+ exp += int((x>>shift)&mask) - bias + 1
+ x &^= mask << shift
+ x |= (-1 + bias) << shift
+ frac = Float64frombits(x)
+ return
+}
diff --git a/go/src/math/gamma.go b/go/src/math/gamma.go
new file mode 100644
index 0000000000000000000000000000000000000000..86c67232580154070c44634d7bdbc6021d66db7f
--- /dev/null
+++ b/go/src/math/gamma.go
@@ -0,0 +1,222 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// The original C code, the long comment, and the constants
+// below are from http://netlib.sandia.gov/cephes/cprob/gamma.c.
+// The go code is a simplified version of the original C.
+//
+// tgamma.c
+//
+// Gamma function
+//
+// SYNOPSIS:
+//
+// double x, y, tgamma();
+// extern int signgam;
+//
+// y = tgamma( x );
+//
+// DESCRIPTION:
+//
+// Returns gamma function of the argument. The result is
+// correctly signed, and the sign (+1 or -1) is also
+// returned in a global (extern) variable named signgam.
+// This variable is also filled in by the logarithmic gamma
+// function lgamma().
+//
+// Arguments |x| <= 34 are reduced by recurrence and the function
+// approximated by a rational function of degree 6/7 in the
+// interval (2,3). Large arguments are handled by Stirling's
+// formula. Large negative arguments are made positive using
+// a reflection formula.
+//
+// ACCURACY:
+//
+// Relative error:
+// arithmetic domain # trials peak rms
+// DEC -34, 34 10000 1.3e-16 2.5e-17
+// IEEE -170,-33 20000 2.3e-15 3.3e-16
+// IEEE -33, 33 20000 9.4e-16 2.2e-16
+// IEEE 33, 171.6 20000 2.3e-15 3.2e-16
+//
+// Error for arguments outside the test range will be larger
+// owing to error amplification by the exponential function.
+//
+// Cephes Math Library Release 2.8: June, 2000
+// Copyright 1984, 1987, 1989, 1992, 2000 by Stephen L. Moshier
+//
+// The readme file at http://netlib.sandia.gov/cephes/ says:
+// Some software in this archive may be from the book _Methods and
+// Programs for Mathematical Functions_ (Prentice-Hall or Simon & Schuster
+// International, 1989) or from the Cephes Mathematical Library, a
+// commercial product. In either event, it is copyrighted by the author.
+// What you see here may be used freely but it comes with no support or
+// guarantee.
+//
+// The two known misprints in the book are repaired here in the
+// source listings for the gamma function and the incomplete beta
+// integral.
+//
+// Stephen L. Moshier
+// moshier@na-net.ornl.gov
+
+var _gamP = [...]float64{
+ 1.60119522476751861407e-04,
+ 1.19135147006586384913e-03,
+ 1.04213797561761569935e-02,
+ 4.76367800457137231464e-02,
+ 2.07448227648435975150e-01,
+ 4.94214826801497100753e-01,
+ 9.99999999999999996796e-01,
+}
+var _gamQ = [...]float64{
+ -2.31581873324120129819e-05,
+ 5.39605580493303397842e-04,
+ -4.45641913851797240494e-03,
+ 1.18139785222060435552e-02,
+ 3.58236398605498653373e-02,
+ -2.34591795718243348568e-01,
+ 7.14304917030273074085e-02,
+ 1.00000000000000000320e+00,
+}
+var _gamS = [...]float64{
+ 7.87311395793093628397e-04,
+ -2.29549961613378126380e-04,
+ -2.68132617805781232825e-03,
+ 3.47222221605458667310e-03,
+ 8.33333333333482257126e-02,
+}
+
+// Gamma function computed by Stirling's formula.
+// The pair of results must be multiplied together to get the actual answer.
+// The multiplication is left to the caller so that, if careful, the caller can avoid
+// infinity for 172 <= x <= 180.
+// The polynomial is valid for 33 <= x <= 172; larger values are only used
+// in reciprocal and produce denormalized floats. The lower precision there
+// masks any imprecision in the polynomial.
+func stirling(x float64) (float64, float64) {
+ if x > 200 {
+ return Inf(1), 1
+ }
+ const (
+ SqrtTwoPi = 2.506628274631000502417
+ MaxStirling = 143.01608
+ )
+ w := 1 / x
+ w = 1 + w*((((_gamS[0]*w+_gamS[1])*w+_gamS[2])*w+_gamS[3])*w+_gamS[4])
+ y1 := Exp(x)
+ y2 := 1.0
+ if x > MaxStirling { // avoid Pow() overflow
+ v := Pow(x, 0.5*x-0.25)
+ y1, y2 = v, v/y1
+ } else {
+ y1 = Pow(x, x-0.5) / y1
+ }
+ return y1, SqrtTwoPi * w * y2
+}
+
+// Gamma returns the Gamma function of x.
+//
+// Special cases are:
+//
+// Gamma(+Inf) = +Inf
+// Gamma(+0) = +Inf
+// Gamma(-0) = -Inf
+// Gamma(x) = NaN for integer x < 0
+// Gamma(-Inf) = NaN
+// Gamma(NaN) = NaN
+func Gamma(x float64) float64 {
+ const Euler = 0.57721566490153286060651209008240243104215933593992 // A001620
+ // special cases
+ switch {
+ case isNegInt(x) || IsInf(x, -1) || IsNaN(x):
+ return NaN()
+ case IsInf(x, 1):
+ return Inf(1)
+ case x == 0:
+ if Signbit(x) {
+ return Inf(-1)
+ }
+ return Inf(1)
+ }
+ q := Abs(x)
+ p := Floor(q)
+ if q > 33 {
+ if x >= 0 {
+ y1, y2 := stirling(x)
+ return y1 * y2
+ }
+ // Note: x is negative but (checked above) not a negative integer,
+ // so x must be small enough to be in range for conversion to int64.
+ // If |x| were >= 2⁶³ it would have to be an integer.
+ signgam := 1
+ if ip := int64(p); ip&1 == 0 {
+ signgam = -1
+ }
+ z := q - p
+ if z > 0.5 {
+ p = p + 1
+ z = q - p
+ }
+ z = q * Sin(Pi*z)
+ if z == 0 {
+ return Inf(signgam)
+ }
+ sq1, sq2 := stirling(q)
+ absz := Abs(z)
+ d := absz * sq1 * sq2
+ if IsInf(d, 0) {
+ z = Pi / absz / sq1 / sq2
+ } else {
+ z = Pi / d
+ }
+ return float64(signgam) * z
+ }
+
+ // Reduce argument
+ z := 1.0
+ for x >= 3 {
+ x = x - 1
+ z = z * x
+ }
+ for x < 0 {
+ if x > -1e-09 {
+ goto small
+ }
+ z = z / x
+ x = x + 1
+ }
+ for x < 2 {
+ if x < 1e-09 {
+ goto small
+ }
+ z = z / x
+ x = x + 1
+ }
+
+ if x == 2 {
+ return z
+ }
+
+ x = x - 2
+ p = (((((x*_gamP[0]+_gamP[1])*x+_gamP[2])*x+_gamP[3])*x+_gamP[4])*x+_gamP[5])*x + _gamP[6]
+ q = ((((((x*_gamQ[0]+_gamQ[1])*x+_gamQ[2])*x+_gamQ[3])*x+_gamQ[4])*x+_gamQ[5])*x+_gamQ[6])*x + _gamQ[7]
+ return z * p / q
+
+small:
+ if x == 0 {
+ return Inf(1)
+ }
+ return z / ((1 + Euler*x) * x)
+}
+
+func isNegInt(x float64) bool {
+ if x < 0 {
+ _, xf := Modf(x)
+ return xf == 0
+ }
+ return false
+}
diff --git a/go/src/math/huge_test.go b/go/src/math/huge_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..2eadb7f89a8a8cbe3fd2ded3ccb1abc6624fa5db
--- /dev/null
+++ b/go/src/math/huge_test.go
@@ -0,0 +1,126 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math_test
+
+import (
+ . "math"
+ "testing"
+)
+
+// Inputs to test trig_reduce
+var trigHuge = []float64{
+ 1 << 28,
+ 1 << 29,
+ 1 << 30,
+ 1 << 35,
+ 1 << 120,
+ 1 << 240,
+ 1 << 480,
+ 1234567891234567 << 180,
+ 1234567891234567 << 300,
+ MaxFloat64,
+}
+
+// Results for trigHuge[i] calculated with https://github.com/robpike/ivy
+// using 4096 bits of working precision. Values requiring less than
+// 102 decimal digits (1 << 120, 1 << 240, 1 << 480, 1234567891234567 << 180)
+// were confirmed via https://keisan.casio.com/
+var cosHuge = []float64{
+ -0.16556897949057876,
+ -0.94517382606089662,
+ 0.78670712294118812,
+ -0.76466301249635305,
+ -0.92587902285483787,
+ 0.93601042593353793,
+ -0.28282777640193788,
+ -0.14616431394103619,
+ -0.79456058210671406,
+ -0.99998768942655994,
+}
+
+var sinHuge = []float64{
+ -0.98619821183697566,
+ 0.32656766301856334,
+ -0.61732641504604217,
+ -0.64443035102329113,
+ 0.37782010936075202,
+ -0.35197227524865778,
+ 0.95917070894368716,
+ 0.98926032637023618,
+ -0.60718488235646949,
+ 0.00496195478918406,
+}
+
+var tanHuge = []float64{
+ 5.95641897939639421,
+ -0.34551069233430392,
+ -0.78469661331920043,
+ 0.84276385870875983,
+ -0.40806638884180424,
+ -0.37603456702698076,
+ -3.39135965054779932,
+ -6.76813854009065030,
+ 0.76417695016604922,
+ -0.00496201587444489,
+}
+
+// Check that trig values of huge angles return accurate results.
+// This confirms that argument reduction works for very large values
+// up to MaxFloat64.
+func TestHugeCos(t *testing.T) {
+ for i := 0; i < len(trigHuge); i++ {
+ f1 := cosHuge[i]
+ f2 := Cos(trigHuge[i])
+ if !close(f1, f2) {
+ t.Errorf("Cos(%g) = %g, want %g", trigHuge[i], f2, f1)
+ }
+ f3 := Cos(-trigHuge[i])
+ if !close(f1, f3) {
+ t.Errorf("Cos(%g) = %g, want %g", -trigHuge[i], f3, f1)
+ }
+ }
+}
+
+func TestHugeSin(t *testing.T) {
+ for i := 0; i < len(trigHuge); i++ {
+ f1 := sinHuge[i]
+ f2 := Sin(trigHuge[i])
+ if !close(f1, f2) {
+ t.Errorf("Sin(%g) = %g, want %g", trigHuge[i], f2, f1)
+ }
+ f3 := Sin(-trigHuge[i])
+ if !close(-f1, f3) {
+ t.Errorf("Sin(%g) = %g, want %g", -trigHuge[i], f3, -f1)
+ }
+ }
+}
+
+func TestHugeSinCos(t *testing.T) {
+ for i := 0; i < len(trigHuge); i++ {
+ f1, g1 := sinHuge[i], cosHuge[i]
+ f2, g2 := Sincos(trigHuge[i])
+ if !close(f1, f2) || !close(g1, g2) {
+ t.Errorf("Sincos(%g) = %g, %g, want %g, %g", trigHuge[i], f2, g2, f1, g1)
+ }
+ f3, g3 := Sincos(-trigHuge[i])
+ if !close(-f1, f3) || !close(g1, g3) {
+ t.Errorf("Sincos(%g) = %g, %g, want %g, %g", -trigHuge[i], f3, g3, -f1, g1)
+ }
+ }
+}
+
+func TestHugeTan(t *testing.T) {
+ for i := 0; i < len(trigHuge); i++ {
+ f1 := tanHuge[i]
+ f2 := Tan(trigHuge[i])
+ if !close(f1, f2) {
+ t.Errorf("Tan(%g) = %g, want %g", trigHuge[i], f2, f1)
+ }
+ f3 := Tan(-trigHuge[i])
+ if !close(-f1, f3) {
+ t.Errorf("Tan(%g) = %g, want %g", -trigHuge[i], f3, -f1)
+ }
+ }
+}
diff --git a/go/src/math/hypot.go b/go/src/math/hypot.go
new file mode 100644
index 0000000000000000000000000000000000000000..03c3602acfe2851ff068ab08ec247116dab0e756
--- /dev/null
+++ b/go/src/math/hypot.go
@@ -0,0 +1,44 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+ Hypot -- sqrt(p*p + q*q), but overflows only if the result does.
+*/
+
+// Hypot returns [Sqrt](p*p + q*q), taking care to avoid
+// unnecessary overflow and underflow.
+//
+// Special cases are:
+//
+// Hypot(±Inf, q) = +Inf
+// Hypot(p, ±Inf) = +Inf
+// Hypot(NaN, q) = NaN
+// Hypot(p, NaN) = NaN
+func Hypot(p, q float64) float64 {
+ if haveArchHypot {
+ return archHypot(p, q)
+ }
+ return hypot(p, q)
+}
+
+func hypot(p, q float64) float64 {
+ p, q = Abs(p), Abs(q)
+ // special cases
+ switch {
+ case IsInf(p, 1) || IsInf(q, 1):
+ return Inf(1)
+ case IsNaN(p) || IsNaN(q):
+ return NaN()
+ }
+ if p < q {
+ p, q = q, p
+ }
+ if p == 0 {
+ return 0
+ }
+ q = q / p
+ return p * Sqrt(1+q*q)
+}
diff --git a/go/src/math/hypot_386.s b/go/src/math/hypot_386.s
new file mode 100644
index 0000000000000000000000000000000000000000..80a8fd3fd02a01ae4b15337e0f6e89ae9b730545
--- /dev/null
+++ b/go/src/math/hypot_386.s
@@ -0,0 +1,59 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// func archHypot(p, q float64) float64
+TEXT ·archHypot(SB),NOSPLIT,$0
+// test bits for not-finite
+ MOVL p_hi+4(FP), AX // high word p
+ ANDL $0x7ff00000, AX
+ CMPL AX, $0x7ff00000
+ JEQ not_finite
+ MOVL q_hi+12(FP), AX // high word q
+ ANDL $0x7ff00000, AX
+ CMPL AX, $0x7ff00000
+ JEQ not_finite
+ FMOVD p+0(FP), F0 // F0=p
+ FABS // F0=|p|
+ FMOVD q+8(FP), F0 // F0=q, F1=|p|
+ FABS // F0=|q|, F1=|p|
+ FUCOMI F0, F1 // compare F0 to F1
+ JCC 2(PC) // jump if F0 >= F1
+ FXCHD F0, F1 // F0=|p| (larger), F1=|q| (smaller)
+ FTST // compare F0 to 0
+ FSTSW AX
+ ANDW $0x4000, AX
+ JNE 10(PC) // jump if F0 = 0
+ FXCHD F0, F1 // F0=q (smaller), F1=p (larger)
+ FDIVD F1, F0 // F0=q(=q/p), F1=p
+ FMULD F0, F0 // F0=q*q, F1=p
+ FLD1 // F0=1, F1=q*q, F2=p
+ FADDDP F0, F1 // F0=1+q*q, F1=p
+ FSQRT // F0=sqrt(1+q*q), F1=p
+ FMULDP F0, F1 // F0=p*sqrt(1+q*q)
+ FMOVDP F0, ret+16(FP)
+ RET
+ FMOVDP F0, F1 // F0=0
+ FMOVDP F0, ret+16(FP)
+ RET
+not_finite:
+// test bits for -Inf or +Inf
+ MOVL p_hi+4(FP), AX // high word p
+ ORL p_lo+0(FP), AX // low word p
+ ANDL $0x7fffffff, AX
+ CMPL AX, $0x7ff00000
+ JEQ is_inf
+ MOVL q_hi+12(FP), AX // high word q
+ ORL q_lo+8(FP), AX // low word q
+ ANDL $0x7fffffff, AX
+ CMPL AX, $0x7ff00000
+ JEQ is_inf
+ MOVL $0x7ff80000, ret_hi+20(FP) // return NaN = 0x7FF8000000000001
+ MOVL $0x00000001, ret_lo+16(FP)
+ RET
+is_inf:
+ MOVL AX, ret_hi+20(FP) // return +Inf = 0x7FF0000000000000
+ MOVL $0x00000000, ret_lo+16(FP)
+ RET
diff --git a/go/src/math/hypot_amd64.s b/go/src/math/hypot_amd64.s
new file mode 100644
index 0000000000000000000000000000000000000000..fe326c928173f51cdacdff63c55c534645b995f9
--- /dev/null
+++ b/go/src/math/hypot_amd64.s
@@ -0,0 +1,52 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+#define PosInf 0x7FF0000000000000
+#define NaN 0x7FF8000000000001
+
+// func archHypot(p, q float64) float64
+TEXT ·archHypot(SB),NOSPLIT,$0
+ // test bits for special cases
+ MOVQ p+0(FP), BX
+ MOVQ $~(1<<63), AX
+ ANDQ AX, BX // p = |p|
+ MOVQ q+8(FP), CX
+ ANDQ AX, CX // q = |q|
+ MOVQ $PosInf, AX
+ CMPQ AX, BX
+ JLE isInfOrNaN
+ CMPQ AX, CX
+ JLE isInfOrNaN
+ // hypot = max * sqrt(1 + (min/max)**2)
+ MOVQ BX, X0
+ MOVQ CX, X1
+ ORQ CX, BX
+ JEQ isZero
+ MOVAPD X0, X2
+ MAXSD X1, X0
+ MINSD X2, X1
+ DIVSD X0, X1
+ MULSD X1, X1
+ ADDSD $1.0, X1
+ SQRTSD X1, X1
+ MULSD X1, X0
+ MOVSD X0, ret+16(FP)
+ RET
+isInfOrNaN:
+ CMPQ AX, BX
+ JEQ isInf
+ CMPQ AX, CX
+ JEQ isInf
+ MOVQ $NaN, AX
+ MOVQ AX, ret+16(FP) // return NaN
+ RET
+isInf:
+ MOVQ AX, ret+16(FP) // return +Inf
+ RET
+isZero:
+ MOVQ $0, AX
+ MOVQ AX, ret+16(FP) // return 0
+ RET
diff --git a/go/src/math/hypot_asm.go b/go/src/math/hypot_asm.go
new file mode 100644
index 0000000000000000000000000000000000000000..852691037f6f4bc4a8e848d17bebc682181073eb
--- /dev/null
+++ b/go/src/math/hypot_asm.go
@@ -0,0 +1,11 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build 386 || amd64
+
+package math
+
+const haveArchHypot = true
+
+func archHypot(p, q float64) float64
diff --git a/go/src/math/hypot_noasm.go b/go/src/math/hypot_noasm.go
new file mode 100644
index 0000000000000000000000000000000000000000..8b64812a1c197e048839bf23858ff4bafbd3aaa7
--- /dev/null
+++ b/go/src/math/hypot_noasm.go
@@ -0,0 +1,13 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !386 && !amd64
+
+package math
+
+const haveArchHypot = false
+
+func archHypot(p, q float64) float64 {
+ panic("not implemented")
+}
diff --git a/go/src/math/j0.go b/go/src/math/j0.go
new file mode 100644
index 0000000000000000000000000000000000000000..a311e18d62d4d3c60127159719bb0df1187745a6
--- /dev/null
+++ b/go/src/math/j0.go
@@ -0,0 +1,429 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+ Bessel function of the first and second kinds of order zero.
+*/
+
+// The original C code and the long comment below are
+// from FreeBSD's /usr/src/lib/msun/src/e_j0.c and
+// came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+// __ieee754_j0(x), __ieee754_y0(x)
+// Bessel function of the first and second kinds of order zero.
+// Method -- j0(x):
+// 1. For tiny x, we use j0(x) = 1 - x**2/4 + x**4/64 - ...
+// 2. Reduce x to |x| since j0(x)=j0(-x), and
+// for x in (0,2)
+// j0(x) = 1-z/4+ z**2*R0/S0, where z = x*x;
+// (precision: |j0-1+z/4-z**2R0/S0 |<2**-63.67 )
+// for x in (2,inf)
+// j0(x) = sqrt(2/(pi*x))*(p0(x)*cos(x0)-q0(x)*sin(x0))
+// where x0 = x-pi/4. It is better to compute sin(x0),cos(x0)
+// as follow:
+// cos(x0) = cos(x)cos(pi/4)+sin(x)sin(pi/4)
+// = 1/sqrt(2) * (cos(x) + sin(x))
+// sin(x0) = sin(x)cos(pi/4)-cos(x)sin(pi/4)
+// = 1/sqrt(2) * (sin(x) - cos(x))
+// (To avoid cancellation, use
+// sin(x) +- cos(x) = -cos(2x)/(sin(x) -+ cos(x))
+// to compute the worse one.)
+//
+// 3 Special cases
+// j0(nan)= nan
+// j0(0) = 1
+// j0(inf) = 0
+//
+// Method -- y0(x):
+// 1. For x<2.
+// Since
+// y0(x) = 2/pi*(j0(x)*(ln(x/2)+Euler) + x**2/4 - ...)
+// therefore y0(x)-2/pi*j0(x)*ln(x) is an even function.
+// We use the following function to approximate y0,
+// y0(x) = U(z)/V(z) + (2/pi)*(j0(x)*ln(x)), z= x**2
+// where
+// U(z) = u00 + u01*z + ... + u06*z**6
+// V(z) = 1 + v01*z + ... + v04*z**4
+// with absolute approximation error bounded by 2**-72.
+// Note: For tiny x, U/V = u0 and j0(x)~1, hence
+// y0(tiny) = u0 + (2/pi)*ln(tiny), (choose tiny<2**-27)
+// 2. For x>=2.
+// y0(x) = sqrt(2/(pi*x))*(p0(x)*cos(x0)+q0(x)*sin(x0))
+// where x0 = x-pi/4. It is better to compute sin(x0),cos(x0)
+// by the method mentioned above.
+// 3. Special cases: y0(0)=-inf, y0(x<0)=NaN, y0(inf)=0.
+//
+
+// J0 returns the order-zero Bessel function of the first kind.
+//
+// Special cases are:
+//
+// J0(±Inf) = 0
+// J0(0) = 1
+// J0(NaN) = NaN
+func J0(x float64) float64 {
+ const (
+ Huge = 1e300
+ TwoM27 = 1.0 / (1 << 27) // 2**-27 0x3e40000000000000
+ TwoM13 = 1.0 / (1 << 13) // 2**-13 0x3f20000000000000
+ Two129 = 1 << 129 // 2**129 0x4800000000000000
+ // R0/S0 on [0, 2]
+ R02 = 1.56249999999999947958e-02 // 0x3F8FFFFFFFFFFFFD
+ R03 = -1.89979294238854721751e-04 // 0xBF28E6A5B61AC6E9
+ R04 = 1.82954049532700665670e-06 // 0x3EBEB1D10C503919
+ R05 = -4.61832688532103189199e-09 // 0xBE33D5E773D63FCE
+ S01 = 1.56191029464890010492e-02 // 0x3F8FFCE882C8C2A4
+ S02 = 1.16926784663337450260e-04 // 0x3F1EA6D2DD57DBF4
+ S03 = 5.13546550207318111446e-07 // 0x3EA13B54CE84D5A9
+ S04 = 1.16614003333790000205e-09 // 0x3E1408BCF4745D8F
+ )
+ // special cases
+ switch {
+ case IsNaN(x):
+ return x
+ case IsInf(x, 0):
+ return 0
+ case x == 0:
+ return 1
+ }
+
+ x = Abs(x)
+ if x >= 2 {
+ s, c := Sincos(x)
+ ss := s - c
+ cc := s + c
+
+ // make sure x+x does not overflow
+ if x < MaxFloat64/2 {
+ z := -Cos(x + x)
+ if s*c < 0 {
+ cc = z / ss
+ } else {
+ ss = z / cc
+ }
+ }
+
+ // j0(x) = 1/sqrt(pi) * (P(0,x)*cc - Q(0,x)*ss) / sqrt(x)
+ // y0(x) = 1/sqrt(pi) * (P(0,x)*ss + Q(0,x)*cc) / sqrt(x)
+
+ var z float64
+ if x > Two129 { // |x| > ~6.8056e+38
+ z = (1 / SqrtPi) * cc / Sqrt(x)
+ } else {
+ u := pzero(x)
+ v := qzero(x)
+ z = (1 / SqrtPi) * (u*cc - v*ss) / Sqrt(x)
+ }
+ return z // |x| >= 2.0
+ }
+ if x < TwoM13 { // |x| < ~1.2207e-4
+ if x < TwoM27 {
+ return 1 // |x| < ~7.4506e-9
+ }
+ return 1 - 0.25*x*x // ~7.4506e-9 < |x| < ~1.2207e-4
+ }
+ z := x * x
+ r := z * (R02 + z*(R03+z*(R04+z*R05)))
+ s := 1 + z*(S01+z*(S02+z*(S03+z*S04)))
+ if x < 1 {
+ return 1 + z*(-0.25+(r/s)) // |x| < 1.00
+ }
+ u := 0.5 * x
+ return (1+u)*(1-u) + z*(r/s) // 1.0 < |x| < 2.0
+}
+
+// Y0 returns the order-zero Bessel function of the second kind.
+//
+// Special cases are:
+//
+// Y0(+Inf) = 0
+// Y0(0) = -Inf
+// Y0(x < 0) = NaN
+// Y0(NaN) = NaN
+func Y0(x float64) float64 {
+ const (
+ TwoM27 = 1.0 / (1 << 27) // 2**-27 0x3e40000000000000
+ Two129 = 1 << 129 // 2**129 0x4800000000000000
+ U00 = -7.38042951086872317523e-02 // 0xBFB2E4D699CBD01F
+ U01 = 1.76666452509181115538e-01 // 0x3FC69D019DE9E3FC
+ U02 = -1.38185671945596898896e-02 // 0xBF8C4CE8B16CFA97
+ U03 = 3.47453432093683650238e-04 // 0x3F36C54D20B29B6B
+ U04 = -3.81407053724364161125e-06 // 0xBECFFEA773D25CAD
+ U05 = 1.95590137035022920206e-08 // 0x3E5500573B4EABD4
+ U06 = -3.98205194132103398453e-11 // 0xBDC5E43D693FB3C8
+ V01 = 1.27304834834123699328e-02 // 0x3F8A127091C9C71A
+ V02 = 7.60068627350353253702e-05 // 0x3F13ECBBF578C6C1
+ V03 = 2.59150851840457805467e-07 // 0x3E91642D7FF202FD
+ V04 = 4.41110311332675467403e-10 // 0x3DFE50183BD6D9EF
+ )
+ // special cases
+ switch {
+ case x < 0 || IsNaN(x):
+ return NaN()
+ case IsInf(x, 1):
+ return 0
+ case x == 0:
+ return Inf(-1)
+ }
+
+ if x >= 2 { // |x| >= 2.0
+
+ // y0(x) = sqrt(2/(pi*x))*(p0(x)*sin(x0)+q0(x)*cos(x0))
+ // where x0 = x-pi/4
+ // Better formula:
+ // cos(x0) = cos(x)cos(pi/4)+sin(x)sin(pi/4)
+ // = 1/sqrt(2) * (sin(x) + cos(x))
+ // sin(x0) = sin(x)cos(3pi/4)-cos(x)sin(3pi/4)
+ // = 1/sqrt(2) * (sin(x) - cos(x))
+ // To avoid cancellation, use
+ // sin(x) +- cos(x) = -cos(2x)/(sin(x) -+ cos(x))
+ // to compute the worse one.
+
+ s, c := Sincos(x)
+ ss := s - c
+ cc := s + c
+
+ // j0(x) = 1/sqrt(pi) * (P(0,x)*cc - Q(0,x)*ss) / sqrt(x)
+ // y0(x) = 1/sqrt(pi) * (P(0,x)*ss + Q(0,x)*cc) / sqrt(x)
+
+ // make sure x+x does not overflow
+ if x < MaxFloat64/2 {
+ z := -Cos(x + x)
+ if s*c < 0 {
+ cc = z / ss
+ } else {
+ ss = z / cc
+ }
+ }
+ var z float64
+ if x > Two129 { // |x| > ~6.8056e+38
+ z = (1 / SqrtPi) * ss / Sqrt(x)
+ } else {
+ u := pzero(x)
+ v := qzero(x)
+ z = (1 / SqrtPi) * (u*ss + v*cc) / Sqrt(x)
+ }
+ return z // |x| >= 2.0
+ }
+ if x <= TwoM27 {
+ return U00 + (2/Pi)*Log(x) // |x| < ~7.4506e-9
+ }
+ z := x * x
+ u := U00 + z*(U01+z*(U02+z*(U03+z*(U04+z*(U05+z*U06)))))
+ v := 1 + z*(V01+z*(V02+z*(V03+z*V04)))
+ return u/v + (2/Pi)*J0(x)*Log(x) // ~7.4506e-9 < |x| < 2.0
+}
+
+// The asymptotic expansions of pzero is
+// 1 - 9/128 s**2 + 11025/98304 s**4 - ..., where s = 1/x.
+// For x >= 2, We approximate pzero by
+// pzero(x) = 1 + (R/S)
+// where R = pR0 + pR1*s**2 + pR2*s**4 + ... + pR5*s**10
+// S = 1 + pS0*s**2 + ... + pS4*s**10
+// and
+// | pzero(x)-1-R/S | <= 2 ** ( -60.26)
+
+// for x in [inf, 8]=1/[0,0.125]
+var p0R8 = [6]float64{
+ 0.00000000000000000000e+00, // 0x0000000000000000
+ -7.03124999999900357484e-02, // 0xBFB1FFFFFFFFFD32
+ -8.08167041275349795626e+00, // 0xC02029D0B44FA779
+ -2.57063105679704847262e+02, // 0xC07011027B19E863
+ -2.48521641009428822144e+03, // 0xC0A36A6ECD4DCAFC
+ -5.25304380490729545272e+03, // 0xC0B4850B36CC643D
+}
+var p0S8 = [5]float64{
+ 1.16534364619668181717e+02, // 0x405D223307A96751
+ 3.83374475364121826715e+03, // 0x40ADF37D50596938
+ 4.05978572648472545552e+04, // 0x40E3D2BB6EB6B05F
+ 1.16752972564375915681e+05, // 0x40FC810F8F9FA9BD
+ 4.76277284146730962675e+04, // 0x40E741774F2C49DC
+}
+
+// for x in [8,4.5454]=1/[0.125,0.22001]
+var p0R5 = [6]float64{
+ -1.14125464691894502584e-11, // 0xBDA918B147E495CC
+ -7.03124940873599280078e-02, // 0xBFB1FFFFE69AFBC6
+ -4.15961064470587782438e+00, // 0xC010A370F90C6BBF
+ -6.76747652265167261021e+01, // 0xC050EB2F5A7D1783
+ -3.31231299649172967747e+02, // 0xC074B3B36742CC63
+ -3.46433388365604912451e+02, // 0xC075A6EF28A38BD7
+}
+var p0S5 = [5]float64{
+ 6.07539382692300335975e+01, // 0x404E60810C98C5DE
+ 1.05125230595704579173e+03, // 0x40906D025C7E2864
+ 5.97897094333855784498e+03, // 0x40B75AF88FBE1D60
+ 9.62544514357774460223e+03, // 0x40C2CCB8FA76FA38
+ 2.40605815922939109441e+03, // 0x40A2CC1DC70BE864
+}
+
+// for x in [4.547,2.8571]=1/[0.2199,0.35001]
+var p0R3 = [6]float64{
+ -2.54704601771951915620e-09, // 0xBE25E1036FE1AA86
+ -7.03119616381481654654e-02, // 0xBFB1FFF6F7C0E24B
+ -2.40903221549529611423e+00, // 0xC00345B2AEA48074
+ -2.19659774734883086467e+01, // 0xC035F74A4CB94E14
+ -5.80791704701737572236e+01, // 0xC04D0A22420A1A45
+ -3.14479470594888503854e+01, // 0xC03F72ACA892D80F
+}
+var p0S3 = [5]float64{
+ 3.58560338055209726349e+01, // 0x4041ED9284077DD3
+ 3.61513983050303863820e+02, // 0x40769839464A7C0E
+ 1.19360783792111533330e+03, // 0x4092A66E6D1061D6
+ 1.12799679856907414432e+03, // 0x40919FFCB8C39B7E
+ 1.73580930813335754692e+02, // 0x4065B296FC379081
+}
+
+// for x in [2.8570,2]=1/[0.3499,0.5]
+var p0R2 = [6]float64{
+ -8.87534333032526411254e-08, // 0xBE77D316E927026D
+ -7.03030995483624743247e-02, // 0xBFB1FF62495E1E42
+ -1.45073846780952986357e+00, // 0xBFF736398A24A843
+ -7.63569613823527770791e+00, // 0xC01E8AF3EDAFA7F3
+ -1.11931668860356747786e+01, // 0xC02662E6C5246303
+ -3.23364579351335335033e+00, // 0xC009DE81AF8FE70F
+}
+var p0S2 = [5]float64{
+ 2.22202997532088808441e+01, // 0x40363865908B5959
+ 1.36206794218215208048e+02, // 0x4061069E0EE8878F
+ 2.70470278658083486789e+02, // 0x4070E78642EA079B
+ 1.53875394208320329881e+02, // 0x40633C033AB6FAFF
+ 1.46576176948256193810e+01, // 0x402D50B344391809
+}
+
+func pzero(x float64) float64 {
+ var p *[6]float64
+ var q *[5]float64
+ if x >= 8 {
+ p = &p0R8
+ q = &p0S8
+ } else if x >= 4.5454 {
+ p = &p0R5
+ q = &p0S5
+ } else if x >= 2.8571 {
+ p = &p0R3
+ q = &p0S3
+ } else if x >= 2 {
+ p = &p0R2
+ q = &p0S2
+ }
+ z := 1 / (x * x)
+ r := p[0] + z*(p[1]+z*(p[2]+z*(p[3]+z*(p[4]+z*p[5]))))
+ s := 1 + z*(q[0]+z*(q[1]+z*(q[2]+z*(q[3]+z*q[4]))))
+ return 1 + r/s
+}
+
+// For x >= 8, the asymptotic expansions of qzero is
+// -1/8 s + 75/1024 s**3 - ..., where s = 1/x.
+// We approximate pzero by
+// qzero(x) = s*(-1.25 + (R/S))
+// where R = qR0 + qR1*s**2 + qR2*s**4 + ... + qR5*s**10
+// S = 1 + qS0*s**2 + ... + qS5*s**12
+// and
+// | qzero(x)/s +1.25-R/S | <= 2**(-61.22)
+
+// for x in [inf, 8]=1/[0,0.125]
+var q0R8 = [6]float64{
+ 0.00000000000000000000e+00, // 0x0000000000000000
+ 7.32421874999935051953e-02, // 0x3FB2BFFFFFFFFE2C
+ 1.17682064682252693899e+01, // 0x402789525BB334D6
+ 5.57673380256401856059e+02, // 0x40816D6315301825
+ 8.85919720756468632317e+03, // 0x40C14D993E18F46D
+ 3.70146267776887834771e+04, // 0x40E212D40E901566
+}
+var q0S8 = [6]float64{
+ 1.63776026895689824414e+02, // 0x406478D5365B39BC
+ 8.09834494656449805916e+03, // 0x40BFA2584E6B0563
+ 1.42538291419120476348e+05, // 0x4101665254D38C3F
+ 8.03309257119514397345e+05, // 0x412883DA83A52B43
+ 8.40501579819060512818e+05, // 0x4129A66B28DE0B3D
+ -3.43899293537866615225e+05, // 0xC114FD6D2C9530C5
+}
+
+// for x in [8,4.5454]=1/[0.125,0.22001]
+var q0R5 = [6]float64{
+ 1.84085963594515531381e-11, // 0x3DB43D8F29CC8CD9
+ 7.32421766612684765896e-02, // 0x3FB2BFFFD172B04C
+ 5.83563508962056953777e+00, // 0x401757B0B9953DD3
+ 1.35111577286449829671e+02, // 0x4060E3920A8788E9
+ 1.02724376596164097464e+03, // 0x40900CF99DC8C481
+ 1.98997785864605384631e+03, // 0x409F17E953C6E3A6
+}
+var q0S5 = [6]float64{
+ 8.27766102236537761883e+01, // 0x4054B1B3FB5E1543
+ 2.07781416421392987104e+03, // 0x40A03BA0DA21C0CE
+ 1.88472887785718085070e+04, // 0x40D267D27B591E6D
+ 5.67511122894947329769e+04, // 0x40EBB5E397E02372
+ 3.59767538425114471465e+04, // 0x40E191181F7A54A0
+ -5.35434275601944773371e+03, // 0xC0B4EA57BEDBC609
+}
+
+// for x in [4.547,2.8571]=1/[0.2199,0.35001]
+var q0R3 = [6]float64{
+ 4.37741014089738620906e-09, // 0x3E32CD036ADECB82
+ 7.32411180042911447163e-02, // 0x3FB2BFEE0E8D0842
+ 3.34423137516170720929e+00, // 0x400AC0FC61149CF5
+ 4.26218440745412650017e+01, // 0x40454F98962DAEDD
+ 1.70808091340565596283e+02, // 0x406559DBE25EFD1F
+ 1.66733948696651168575e+02, // 0x4064D77C81FA21E0
+}
+var q0S3 = [6]float64{
+ 4.87588729724587182091e+01, // 0x40486122BFE343A6
+ 7.09689221056606015736e+02, // 0x40862D8386544EB3
+ 3.70414822620111362994e+03, // 0x40ACF04BE44DFC63
+ 6.46042516752568917582e+03, // 0x40B93C6CD7C76A28
+ 2.51633368920368957333e+03, // 0x40A3A8AAD94FB1C0
+ -1.49247451836156386662e+02, // 0xC062A7EB201CF40F
+}
+
+// for x in [2.8570,2]=1/[0.3499,0.5]
+var q0R2 = [6]float64{
+ 1.50444444886983272379e-07, // 0x3E84313B54F76BDB
+ 7.32234265963079278272e-02, // 0x3FB2BEC53E883E34
+ 1.99819174093815998816e+00, // 0x3FFFF897E727779C
+ 1.44956029347885735348e+01, // 0x402CFDBFAAF96FE5
+ 3.16662317504781540833e+01, // 0x403FAA8E29FBDC4A
+ 1.62527075710929267416e+01, // 0x403040B171814BB4
+}
+var q0S2 = [6]float64{
+ 3.03655848355219184498e+01, // 0x403E5D96F7C07AED
+ 2.69348118608049844624e+02, // 0x4070D591E4D14B40
+ 8.44783757595320139444e+02, // 0x408A664522B3BF22
+ 8.82935845112488550512e+02, // 0x408B977C9C5CC214
+ 2.12666388511798828631e+02, // 0x406A95530E001365
+ -5.31095493882666946917e+00, // 0xC0153E6AF8B32931
+}
+
+func qzero(x float64) float64 {
+ var p, q *[6]float64
+ if x >= 8 {
+ p = &q0R8
+ q = &q0S8
+ } else if x >= 4.5454 {
+ p = &q0R5
+ q = &q0S5
+ } else if x >= 2.8571 {
+ p = &q0R3
+ q = &q0S3
+ } else if x >= 2 {
+ p = &q0R2
+ q = &q0S2
+ }
+ z := 1 / (x * x)
+ r := p[0] + z*(p[1]+z*(p[2]+z*(p[3]+z*(p[4]+z*p[5]))))
+ s := 1 + z*(q[0]+z*(q[1]+z*(q[2]+z*(q[3]+z*(q[4]+z*q[5])))))
+ return (-0.125 + r/s) / x
+}
diff --git a/go/src/math/j1.go b/go/src/math/j1.go
new file mode 100644
index 0000000000000000000000000000000000000000..cc19e75b95002a6ce3de86d17bb1e73639de8d9b
--- /dev/null
+++ b/go/src/math/j1.go
@@ -0,0 +1,424 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+ Bessel function of the first and second kinds of order one.
+*/
+
+// The original C code and the long comment below are
+// from FreeBSD's /usr/src/lib/msun/src/e_j1.c and
+// came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+// __ieee754_j1(x), __ieee754_y1(x)
+// Bessel function of the first and second kinds of order one.
+// Method -- j1(x):
+// 1. For tiny x, we use j1(x) = x/2 - x**3/16 + x**5/384 - ...
+// 2. Reduce x to |x| since j1(x)=-j1(-x), and
+// for x in (0,2)
+// j1(x) = x/2 + x*z*R0/S0, where z = x*x;
+// (precision: |j1/x - 1/2 - R0/S0 |<2**-61.51 )
+// for x in (2,inf)
+// j1(x) = sqrt(2/(pi*x))*(p1(x)*cos(x1)-q1(x)*sin(x1))
+// y1(x) = sqrt(2/(pi*x))*(p1(x)*sin(x1)+q1(x)*cos(x1))
+// where x1 = x-3*pi/4. It is better to compute sin(x1),cos(x1)
+// as follow:
+// cos(x1) = cos(x)cos(3pi/4)+sin(x)sin(3pi/4)
+// = 1/sqrt(2) * (sin(x) - cos(x))
+// sin(x1) = sin(x)cos(3pi/4)-cos(x)sin(3pi/4)
+// = -1/sqrt(2) * (sin(x) + cos(x))
+// (To avoid cancellation, use
+// sin(x) +- cos(x) = -cos(2x)/(sin(x) -+ cos(x))
+// to compute the worse one.)
+//
+// 3 Special cases
+// j1(nan)= nan
+// j1(0) = 0
+// j1(inf) = 0
+//
+// Method -- y1(x):
+// 1. screen out x<=0 cases: y1(0)=-inf, y1(x<0)=NaN
+// 2. For x<2.
+// Since
+// y1(x) = 2/pi*(j1(x)*(ln(x/2)+Euler)-1/x-x/2+5/64*x**3-...)
+// therefore y1(x)-2/pi*j1(x)*ln(x)-1/x is an odd function.
+// We use the following function to approximate y1,
+// y1(x) = x*U(z)/V(z) + (2/pi)*(j1(x)*ln(x)-1/x), z= x**2
+// where for x in [0,2] (abs err less than 2**-65.89)
+// U(z) = U0[0] + U0[1]*z + ... + U0[4]*z**4
+// V(z) = 1 + v0[0]*z + ... + v0[4]*z**5
+// Note: For tiny x, 1/x dominate y1 and hence
+// y1(tiny) = -2/pi/tiny, (choose tiny<2**-54)
+// 3. For x>=2.
+// y1(x) = sqrt(2/(pi*x))*(p1(x)*sin(x1)+q1(x)*cos(x1))
+// where x1 = x-3*pi/4. It is better to compute sin(x1),cos(x1)
+// by method mentioned above.
+
+// J1 returns the order-one Bessel function of the first kind.
+//
+// Special cases are:
+//
+// J1(±Inf) = 0
+// J1(NaN) = NaN
+func J1(x float64) float64 {
+ const (
+ TwoM27 = 1.0 / (1 << 27) // 2**-27 0x3e40000000000000
+ Two129 = 1 << 129 // 2**129 0x4800000000000000
+ // R0/S0 on [0, 2]
+ R00 = -6.25000000000000000000e-02 // 0xBFB0000000000000
+ R01 = 1.40705666955189706048e-03 // 0x3F570D9F98472C61
+ R02 = -1.59955631084035597520e-05 // 0xBEF0C5C6BA169668
+ R03 = 4.96727999609584448412e-08 // 0x3E6AAAFA46CA0BD9
+ S01 = 1.91537599538363460805e-02 // 0x3F939D0B12637E53
+ S02 = 1.85946785588630915560e-04 // 0x3F285F56B9CDF664
+ S03 = 1.17718464042623683263e-06 // 0x3EB3BFF8333F8498
+ S04 = 5.04636257076217042715e-09 // 0x3E35AC88C97DFF2C
+ S05 = 1.23542274426137913908e-11 // 0x3DAB2ACFCFB97ED8
+ )
+ // special cases
+ switch {
+ case IsNaN(x):
+ return x
+ case IsInf(x, 0) || x == 0:
+ return 0
+ }
+
+ sign := false
+ if x < 0 {
+ x = -x
+ sign = true
+ }
+ if x >= 2 {
+ s, c := Sincos(x)
+ ss := -s - c
+ cc := s - c
+
+ // make sure x+x does not overflow
+ if x < MaxFloat64/2 {
+ z := Cos(x + x)
+ if s*c > 0 {
+ cc = z / ss
+ } else {
+ ss = z / cc
+ }
+ }
+
+ // j1(x) = 1/sqrt(pi) * (P(1,x)*cc - Q(1,x)*ss) / sqrt(x)
+ // y1(x) = 1/sqrt(pi) * (P(1,x)*ss + Q(1,x)*cc) / sqrt(x)
+
+ var z float64
+ if x > Two129 {
+ z = (1 / SqrtPi) * cc / Sqrt(x)
+ } else {
+ u := pone(x)
+ v := qone(x)
+ z = (1 / SqrtPi) * (u*cc - v*ss) / Sqrt(x)
+ }
+ if sign {
+ return -z
+ }
+ return z
+ }
+ if x < TwoM27 { // |x|<2**-27
+ return 0.5 * x // inexact if x!=0 necessary
+ }
+ z := x * x
+ r := z * (R00 + z*(R01+z*(R02+z*R03)))
+ s := 1.0 + z*(S01+z*(S02+z*(S03+z*(S04+z*S05))))
+ r *= x
+ z = 0.5*x + r/s
+ if sign {
+ return -z
+ }
+ return z
+}
+
+// Y1 returns the order-one Bessel function of the second kind.
+//
+// Special cases are:
+//
+// Y1(+Inf) = 0
+// Y1(0) = -Inf
+// Y1(x < 0) = NaN
+// Y1(NaN) = NaN
+func Y1(x float64) float64 {
+ const (
+ TwoM54 = 1.0 / (1 << 54) // 2**-54 0x3c90000000000000
+ Two129 = 1 << 129 // 2**129 0x4800000000000000
+ U00 = -1.96057090646238940668e-01 // 0xBFC91866143CBC8A
+ U01 = 5.04438716639811282616e-02 // 0x3FA9D3C776292CD1
+ U02 = -1.91256895875763547298e-03 // 0xBF5F55E54844F50F
+ U03 = 2.35252600561610495928e-05 // 0x3EF8AB038FA6B88E
+ U04 = -9.19099158039878874504e-08 // 0xBE78AC00569105B8
+ V00 = 1.99167318236649903973e-02 // 0x3F94650D3F4DA9F0
+ V01 = 2.02552581025135171496e-04 // 0x3F2A8C896C257764
+ V02 = 1.35608801097516229404e-06 // 0x3EB6C05A894E8CA6
+ V03 = 6.22741452364621501295e-09 // 0x3E3ABF1D5BA69A86
+ V04 = 1.66559246207992079114e-11 // 0x3DB25039DACA772A
+ )
+ // special cases
+ switch {
+ case x < 0 || IsNaN(x):
+ return NaN()
+ case IsInf(x, 1):
+ return 0
+ case x == 0:
+ return Inf(-1)
+ }
+
+ if x >= 2 {
+ s, c := Sincos(x)
+ ss := -s - c
+ cc := s - c
+
+ // make sure x+x does not overflow
+ if x < MaxFloat64/2 {
+ z := Cos(x + x)
+ if s*c > 0 {
+ cc = z / ss
+ } else {
+ ss = z / cc
+ }
+ }
+ // y1(x) = sqrt(2/(pi*x))*(p1(x)*sin(x0)+q1(x)*cos(x0))
+ // where x0 = x-3pi/4
+ // Better formula:
+ // cos(x0) = cos(x)cos(3pi/4)+sin(x)sin(3pi/4)
+ // = 1/sqrt(2) * (sin(x) - cos(x))
+ // sin(x0) = sin(x)cos(3pi/4)-cos(x)sin(3pi/4)
+ // = -1/sqrt(2) * (cos(x) + sin(x))
+ // To avoid cancellation, use
+ // sin(x) +- cos(x) = -cos(2x)/(sin(x) -+ cos(x))
+ // to compute the worse one.
+
+ var z float64
+ if x > Two129 {
+ z = (1 / SqrtPi) * ss / Sqrt(x)
+ } else {
+ u := pone(x)
+ v := qone(x)
+ z = (1 / SqrtPi) * (u*ss + v*cc) / Sqrt(x)
+ }
+ return z
+ }
+ if x <= TwoM54 { // x < 2**-54
+ return -(2 / Pi) / x
+ }
+ z := x * x
+ u := U00 + z*(U01+z*(U02+z*(U03+z*U04)))
+ v := 1 + z*(V00+z*(V01+z*(V02+z*(V03+z*V04))))
+ return x*(u/v) + (2/Pi)*(J1(x)*Log(x)-1/x)
+}
+
+// For x >= 8, the asymptotic expansions of pone is
+// 1 + 15/128 s**2 - 4725/2**15 s**4 - ..., where s = 1/x.
+// We approximate pone by
+// pone(x) = 1 + (R/S)
+// where R = pr0 + pr1*s**2 + pr2*s**4 + ... + pr5*s**10
+// S = 1 + ps0*s**2 + ... + ps4*s**10
+// and
+// | pone(x)-1-R/S | <= 2**(-60.06)
+
+// for x in [inf, 8]=1/[0,0.125]
+var p1R8 = [6]float64{
+ 0.00000000000000000000e+00, // 0x0000000000000000
+ 1.17187499999988647970e-01, // 0x3FBDFFFFFFFFFCCE
+ 1.32394806593073575129e+01, // 0x402A7A9D357F7FCE
+ 4.12051854307378562225e+02, // 0x4079C0D4652EA590
+ 3.87474538913960532227e+03, // 0x40AE457DA3A532CC
+ 7.91447954031891731574e+03, // 0x40BEEA7AC32782DD
+}
+var p1S8 = [5]float64{
+ 1.14207370375678408436e+02, // 0x405C8D458E656CAC
+ 3.65093083420853463394e+03, // 0x40AC85DC964D274F
+ 3.69562060269033463555e+04, // 0x40E20B8697C5BB7F
+ 9.76027935934950801311e+04, // 0x40F7D42CB28F17BB
+ 3.08042720627888811578e+04, // 0x40DE1511697A0B2D
+}
+
+// for x in [8,4.5454] = 1/[0.125,0.22001]
+var p1R5 = [6]float64{
+ 1.31990519556243522749e-11, // 0x3DAD0667DAE1CA7D
+ 1.17187493190614097638e-01, // 0x3FBDFFFFE2C10043
+ 6.80275127868432871736e+00, // 0x401B36046E6315E3
+ 1.08308182990189109773e+02, // 0x405B13B9452602ED
+ 5.17636139533199752805e+02, // 0x40802D16D052D649
+ 5.28715201363337541807e+02, // 0x408085B8BB7E0CB7
+}
+var p1S5 = [5]float64{
+ 5.92805987221131331921e+01, // 0x404DA3EAA8AF633D
+ 9.91401418733614377743e+02, // 0x408EFB361B066701
+ 5.35326695291487976647e+03, // 0x40B4E9445706B6FB
+ 7.84469031749551231769e+03, // 0x40BEA4B0B8A5BB15
+ 1.50404688810361062679e+03, // 0x40978030036F5E51
+}
+
+// for x in[4.5453,2.8571] = 1/[0.2199,0.35001]
+var p1R3 = [6]float64{
+ 3.02503916137373618024e-09, // 0x3E29FC21A7AD9EDD
+ 1.17186865567253592491e-01, // 0x3FBDFFF55B21D17B
+ 3.93297750033315640650e+00, // 0x400F76BCE85EAD8A
+ 3.51194035591636932736e+01, // 0x40418F489DA6D129
+ 9.10550110750781271918e+01, // 0x4056C3854D2C1837
+ 4.85590685197364919645e+01, // 0x4048478F8EA83EE5
+}
+var p1S3 = [5]float64{
+ 3.47913095001251519989e+01, // 0x40416549A134069C
+ 3.36762458747825746741e+02, // 0x40750C3307F1A75F
+ 1.04687139975775130551e+03, // 0x40905B7C5037D523
+ 8.90811346398256432622e+02, // 0x408BD67DA32E31E9
+ 1.03787932439639277504e+02, // 0x4059F26D7C2EED53
+}
+
+// for x in [2.8570,2] = 1/[0.3499,0.5]
+var p1R2 = [6]float64{
+ 1.07710830106873743082e-07, // 0x3E7CE9D4F65544F4
+ 1.17176219462683348094e-01, // 0x3FBDFF42BE760D83
+ 2.36851496667608785174e+00, // 0x4002F2B7F98FAEC0
+ 1.22426109148261232917e+01, // 0x40287C377F71A964
+ 1.76939711271687727390e+01, // 0x4031B1A8177F8EE2
+ 5.07352312588818499250e+00, // 0x40144B49A574C1FE
+}
+var p1S2 = [5]float64{
+ 2.14364859363821409488e+01, // 0x40356FBD8AD5ECDC
+ 1.25290227168402751090e+02, // 0x405F529314F92CD5
+ 2.32276469057162813669e+02, // 0x406D08D8D5A2DBD9
+ 1.17679373287147100768e+02, // 0x405D6B7ADA1884A9
+ 8.36463893371618283368e+00, // 0x4020BAB1F44E5192
+}
+
+func pone(x float64) float64 {
+ var p *[6]float64
+ var q *[5]float64
+ if x >= 8 {
+ p = &p1R8
+ q = &p1S8
+ } else if x >= 4.5454 {
+ p = &p1R5
+ q = &p1S5
+ } else if x >= 2.8571 {
+ p = &p1R3
+ q = &p1S3
+ } else if x >= 2 {
+ p = &p1R2
+ q = &p1S2
+ }
+ z := 1 / (x * x)
+ r := p[0] + z*(p[1]+z*(p[2]+z*(p[3]+z*(p[4]+z*p[5]))))
+ s := 1.0 + z*(q[0]+z*(q[1]+z*(q[2]+z*(q[3]+z*q[4]))))
+ return 1 + r/s
+}
+
+// For x >= 8, the asymptotic expansions of qone is
+// 3/8 s - 105/1024 s**3 - ..., where s = 1/x.
+// We approximate qone by
+// qone(x) = s*(0.375 + (R/S))
+// where R = qr1*s**2 + qr2*s**4 + ... + qr5*s**10
+// S = 1 + qs1*s**2 + ... + qs6*s**12
+// and
+// | qone(x)/s -0.375-R/S | <= 2**(-61.13)
+
+// for x in [inf, 8] = 1/[0,0.125]
+var q1R8 = [6]float64{
+ 0.00000000000000000000e+00, // 0x0000000000000000
+ -1.02539062499992714161e-01, // 0xBFBA3FFFFFFFFDF3
+ -1.62717534544589987888e+01, // 0xC0304591A26779F7
+ -7.59601722513950107896e+02, // 0xC087BCD053E4B576
+ -1.18498066702429587167e+04, // 0xC0C724E740F87415
+ -4.84385124285750353010e+04, // 0xC0E7A6D065D09C6A
+}
+var q1S8 = [6]float64{
+ 1.61395369700722909556e+02, // 0x40642CA6DE5BCDE5
+ 7.82538599923348465381e+03, // 0x40BE9162D0D88419
+ 1.33875336287249578163e+05, // 0x4100579AB0B75E98
+ 7.19657723683240939863e+05, // 0x4125F65372869C19
+ 6.66601232617776375264e+05, // 0x412457D27719AD5C
+ -2.94490264303834643215e+05, // 0xC111F9690EA5AA18
+}
+
+// for x in [8,4.5454] = 1/[0.125,0.22001]
+var q1R5 = [6]float64{
+ -2.08979931141764104297e-11, // 0xBDB6FA431AA1A098
+ -1.02539050241375426231e-01, // 0xBFBA3FFFCB597FEF
+ -8.05644828123936029840e+00, // 0xC0201CE6CA03AD4B
+ -1.83669607474888380239e+02, // 0xC066F56D6CA7B9B0
+ -1.37319376065508163265e+03, // 0xC09574C66931734F
+ -2.61244440453215656817e+03, // 0xC0A468E388FDA79D
+}
+var q1S5 = [6]float64{
+ 8.12765501384335777857e+01, // 0x405451B2FF5A11B2
+ 1.99179873460485964642e+03, // 0x409F1F31E77BF839
+ 1.74684851924908907677e+04, // 0x40D10F1F0D64CE29
+ 4.98514270910352279316e+04, // 0x40E8576DAABAD197
+ 2.79480751638918118260e+04, // 0x40DB4B04CF7C364B
+ -4.71918354795128470869e+03, // 0xC0B26F2EFCFFA004
+}
+
+// for x in [4.5454,2.8571] = 1/[0.2199,0.35001] ???
+var q1R3 = [6]float64{
+ -5.07831226461766561369e-09, // 0xBE35CFA9D38FC84F
+ -1.02537829820837089745e-01, // 0xBFBA3FEB51AEED54
+ -4.61011581139473403113e+00, // 0xC01270C23302D9FF
+ -5.78472216562783643212e+01, // 0xC04CEC71C25D16DA
+ -2.28244540737631695038e+02, // 0xC06C87D34718D55F
+ -2.19210128478909325622e+02, // 0xC06B66B95F5C1BF6
+}
+var q1S3 = [6]float64{
+ 4.76651550323729509273e+01, // 0x4047D523CCD367E4
+ 6.73865112676699709482e+02, // 0x40850EEBC031EE3E
+ 3.38015286679526343505e+03, // 0x40AA684E448E7C9A
+ 5.54772909720722782367e+03, // 0x40B5ABBAA61D54A6
+ 1.90311919338810798763e+03, // 0x409DBC7A0DD4DF4B
+ -1.35201191444307340817e+02, // 0xC060E670290A311F
+}
+
+// for x in [2.8570,2] = 1/[0.3499,0.5]
+var q1R2 = [6]float64{
+ -1.78381727510958865572e-07, // 0xBE87F12644C626D2
+ -1.02517042607985553460e-01, // 0xBFBA3E8E9148B010
+ -2.75220568278187460720e+00, // 0xC006048469BB4EDA
+ -1.96636162643703720221e+01, // 0xC033A9E2C168907F
+ -4.23253133372830490089e+01, // 0xC04529A3DE104AAA
+ -2.13719211703704061733e+01, // 0xC0355F3639CF6E52
+}
+var q1S2 = [6]float64{
+ 2.95333629060523854548e+01, // 0x403D888A78AE64FF
+ 2.52981549982190529136e+02, // 0x406F9F68DB821CBA
+ 7.57502834868645436472e+02, // 0x4087AC05CE49A0F7
+ 7.39393205320467245656e+02, // 0x40871B2548D4C029
+ 1.55949003336666123687e+02, // 0x40637E5E3C3ED8D4
+ -4.95949898822628210127e+00, // 0xC013D686E71BE86B
+}
+
+func qone(x float64) float64 {
+ var p, q *[6]float64
+ if x >= 8 {
+ p = &q1R8
+ q = &q1S8
+ } else if x >= 4.5454 {
+ p = &q1R5
+ q = &q1S5
+ } else if x >= 2.8571 {
+ p = &q1R3
+ q = &q1S3
+ } else if x >= 2 {
+ p = &q1R2
+ q = &q1S2
+ }
+ z := 1 / (x * x)
+ r := p[0] + z*(p[1]+z*(p[2]+z*(p[3]+z*(p[4]+z*p[5]))))
+ s := 1 + z*(q[0]+z*(q[1]+z*(q[2]+z*(q[3]+z*(q[4]+z*q[5])))))
+ return (0.375 + r/s) / x
+}
diff --git a/go/src/math/jn.go b/go/src/math/jn.go
new file mode 100644
index 0000000000000000000000000000000000000000..3491692a96ca7f3e570a2545d1cca7353ad6524a
--- /dev/null
+++ b/go/src/math/jn.go
@@ -0,0 +1,306 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+ Bessel function of the first and second kinds of order n.
+*/
+
+// The original C code and the long comment below are
+// from FreeBSD's /usr/src/lib/msun/src/e_jn.c and
+// came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+// __ieee754_jn(n, x), __ieee754_yn(n, x)
+// floating point Bessel's function of the 1st and 2nd kind
+// of order n
+//
+// Special cases:
+// y0(0)=y1(0)=yn(n,0) = -inf with division by zero signal;
+// y0(-ve)=y1(-ve)=yn(n,-ve) are NaN with invalid signal.
+// Note 2. About jn(n,x), yn(n,x)
+// For n=0, j0(x) is called,
+// for n=1, j1(x) is called,
+// for nx, a continued fraction approximation to
+// j(n,x)/j(n-1,x) is evaluated and then backward
+// recursion is used starting from a supposed value
+// for j(n,x). The resulting value of j(0,x) is
+// compared with the actual value to correct the
+// supposed value of j(n,x).
+//
+// yn(n,x) is similar in all respects, except
+// that forward recursion is used for all
+// values of n>1.
+
+// Jn returns the order-n Bessel function of the first kind.
+//
+// Special cases are:
+//
+// Jn(n, ±Inf) = 0
+// Jn(n, NaN) = NaN
+func Jn(n int, x float64) float64 {
+ const (
+ TwoM29 = 1.0 / (1 << 29) // 2**-29 0x3e10000000000000
+ Two302 = 1 << 302 // 2**302 0x52D0000000000000
+ )
+ // special cases
+ switch {
+ case IsNaN(x):
+ return x
+ case IsInf(x, 0):
+ return 0
+ }
+ // J(-n, x) = (-1)**n * J(n, x), J(n, -x) = (-1)**n * J(n, x)
+ // Thus, J(-n, x) = J(n, -x)
+
+ if n == 0 {
+ return J0(x)
+ }
+ if x == 0 {
+ return 0
+ }
+ if n < 0 {
+ n, x = -n, -x
+ }
+ if n == 1 {
+ return J1(x)
+ }
+ sign := false
+ if x < 0 {
+ x = -x
+ if n&1 == 1 {
+ sign = true // odd n and negative x
+ }
+ }
+ var b float64
+ if float64(n) <= x {
+ // Safe to use J(n+1,x)=2n/x *J(n,x)-J(n-1,x)
+ if x >= Two302 { // x > 2**302
+
+ // (x >> n**2)
+ // Jn(x) = cos(x-(2n+1)*pi/4)*sqrt(2/x*pi)
+ // Yn(x) = sin(x-(2n+1)*pi/4)*sqrt(2/x*pi)
+ // Let s=sin(x), c=cos(x),
+ // xn=x-(2n+1)*pi/4, sqt2 = sqrt(2),then
+ //
+ // n sin(xn)*sqt2 cos(xn)*sqt2
+ // ----------------------------------
+ // 0 s-c c+s
+ // 1 -s-c -c+s
+ // 2 -s+c -c-s
+ // 3 s+c c-s
+
+ var temp float64
+ switch s, c := Sincos(x); n & 3 {
+ case 0:
+ temp = c + s
+ case 1:
+ temp = -c + s
+ case 2:
+ temp = -c - s
+ case 3:
+ temp = c - s
+ }
+ b = (1 / SqrtPi) * temp / Sqrt(x)
+ } else {
+ b = J1(x)
+ for i, a := 1, J0(x); i < n; i++ {
+ a, b = b, b*(float64(i+i)/x)-a // avoid underflow
+ }
+ }
+ } else {
+ if x < TwoM29 { // x < 2**-29
+ // x is tiny, return the first Taylor expansion of J(n,x)
+ // J(n,x) = 1/n!*(x/2)**n - ...
+
+ if n > 33 { // underflow
+ b = 0
+ } else {
+ temp := x * 0.5
+ b = temp
+ a := 1.0
+ for i := 2; i <= n; i++ {
+ a *= float64(i) // a = n!
+ b *= temp // b = (x/2)**n
+ }
+ b /= a
+ }
+ } else {
+ // use backward recurrence
+ // x x**2 x**2
+ // J(n,x)/J(n-1,x) = ---- ------ ------ .....
+ // 2n - 2(n+1) - 2(n+2)
+ //
+ // 1 1 1
+ // (for large x) = ---- ------ ------ .....
+ // 2n 2(n+1) 2(n+2)
+ // -- - ------ - ------ -
+ // x x x
+ //
+ // Let w = 2n/x and h=2/x, then the above quotient
+ // is equal to the continued fraction:
+ // 1
+ // = -----------------------
+ // 1
+ // w - -----------------
+ // 1
+ // w+h - ---------
+ // w+2h - ...
+ //
+ // To determine how many terms needed, let
+ // Q(0) = w, Q(1) = w(w+h) - 1,
+ // Q(k) = (w+k*h)*Q(k-1) - Q(k-2),
+ // When Q(k) > 1e4 good for single
+ // When Q(k) > 1e9 good for double
+ // When Q(k) > 1e17 good for quadruple
+
+ // determine k
+ w := float64(n+n) / x
+ h := 2 / x
+ q0 := w
+ z := w + h
+ q1 := w*z - 1
+ k := 1
+ for q1 < 1e9 {
+ k++
+ z += h
+ q0, q1 = q1, z*q1-q0
+ }
+ m := n + n
+ t := 0.0
+ for i := 2 * (n + k); i >= m; i -= 2 {
+ t = 1 / (float64(i)/x - t)
+ }
+ a := t
+ b = 1
+ // estimate log((2/x)**n*n!) = n*log(2/x)+n*ln(n)
+ // Hence, if n*(log(2n/x)) > ...
+ // single 8.8722839355e+01
+ // double 7.09782712893383973096e+02
+ // long double 1.1356523406294143949491931077970765006170e+04
+ // then recurrent value may overflow and the result is
+ // likely underflow to zero
+
+ tmp := float64(n)
+ v := 2 / x
+ tmp = tmp * Log(Abs(v*tmp))
+ if tmp < 7.09782712893383973096e+02 {
+ for i := n - 1; i > 0; i-- {
+ di := float64(i + i)
+ a, b = b, b*di/x-a
+ }
+ } else {
+ for i := n - 1; i > 0; i-- {
+ di := float64(i + i)
+ a, b = b, b*di/x-a
+ // scale b to avoid spurious overflow
+ if b > 1e100 {
+ a /= b
+ t /= b
+ b = 1
+ }
+ }
+ }
+ b = t * J0(x) / b
+ }
+ }
+ if sign {
+ return -b
+ }
+ return b
+}
+
+// Yn returns the order-n Bessel function of the second kind.
+//
+// Special cases are:
+//
+// Yn(n, +Inf) = 0
+// Yn(n ≥ 0, 0) = -Inf
+// Yn(n < 0, 0) = +Inf if n is odd, -Inf if n is even
+// Yn(n, x < 0) = NaN
+// Yn(n, NaN) = NaN
+func Yn(n int, x float64) float64 {
+ const Two302 = 1 << 302 // 2**302 0x52D0000000000000
+ // special cases
+ switch {
+ case x < 0 || IsNaN(x):
+ return NaN()
+ case IsInf(x, 1):
+ return 0
+ }
+
+ if n == 0 {
+ return Y0(x)
+ }
+ if x == 0 {
+ if n < 0 && n&1 == 1 {
+ return Inf(1)
+ }
+ return Inf(-1)
+ }
+ sign := false
+ if n < 0 {
+ n = -n
+ if n&1 == 1 {
+ sign = true // sign true if n < 0 && |n| odd
+ }
+ }
+ if n == 1 {
+ if sign {
+ return -Y1(x)
+ }
+ return Y1(x)
+ }
+ var b float64
+ if x >= Two302 { // x > 2**302
+ // (x >> n**2)
+ // Jn(x) = cos(x-(2n+1)*pi/4)*sqrt(2/x*pi)
+ // Yn(x) = sin(x-(2n+1)*pi/4)*sqrt(2/x*pi)
+ // Let s=sin(x), c=cos(x),
+ // xn=x-(2n+1)*pi/4, sqt2 = sqrt(2),then
+ //
+ // n sin(xn)*sqt2 cos(xn)*sqt2
+ // ----------------------------------
+ // 0 s-c c+s
+ // 1 -s-c -c+s
+ // 2 -s+c -c-s
+ // 3 s+c c-s
+
+ var temp float64
+ switch s, c := Sincos(x); n & 3 {
+ case 0:
+ temp = s - c
+ case 1:
+ temp = -s - c
+ case 2:
+ temp = -s + c
+ case 3:
+ temp = s + c
+ }
+ b = (1 / SqrtPi) * temp / Sqrt(x)
+ } else {
+ a := Y0(x)
+ b = Y1(x)
+ // quit if b is -inf
+ for i := 1; i < n && !IsInf(b, -1); i++ {
+ a, b = b, (float64(i+i)/x)*b-a
+ }
+ }
+ if sign {
+ return -b
+ }
+ return b
+}
diff --git a/go/src/math/ldexp.go b/go/src/math/ldexp.go
new file mode 100644
index 0000000000000000000000000000000000000000..fad099dfa26e6f18aad278766f159d2130384b5c
--- /dev/null
+++ b/go/src/math/ldexp.go
@@ -0,0 +1,51 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Ldexp is the inverse of [Frexp].
+// It returns frac × 2**exp.
+//
+// Special cases are:
+//
+// Ldexp(±0, exp) = ±0
+// Ldexp(±Inf, exp) = ±Inf
+// Ldexp(NaN, exp) = NaN
+func Ldexp(frac float64, exp int) float64 {
+ if haveArchLdexp {
+ return archLdexp(frac, exp)
+ }
+ return ldexp(frac, exp)
+}
+
+func ldexp(frac float64, exp int) float64 {
+ // special cases
+ switch {
+ case frac == 0:
+ return frac // correctly return -0
+ case IsInf(frac, 0) || IsNaN(frac):
+ return frac
+ }
+ frac, e := normalize(frac)
+ exp += e
+ x := Float64bits(frac)
+ exp += int(x>>shift)&mask - bias
+ if exp < -1075 {
+ return Copysign(0, frac) // underflow
+ }
+ if exp > 1023 { // overflow
+ if frac < 0 {
+ return Inf(-1)
+ }
+ return Inf(1)
+ }
+ var m float64 = 1
+ if exp < -1022 { // denormal
+ exp += 53
+ m = 1.0 / (1 << 53) // 2**-53
+ }
+ x &^= mask << shift
+ x |= uint64(exp+bias) << shift
+ return m * Float64frombits(x)
+}
diff --git a/go/src/math/lgamma.go b/go/src/math/lgamma.go
new file mode 100644
index 0000000000000000000000000000000000000000..5a7ea2a58c7cf0a918b78938369090b2d518591f
--- /dev/null
+++ b/go/src/math/lgamma.go
@@ -0,0 +1,366 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+ Floating-point logarithm of the Gamma function.
+*/
+
+// The original C code and the long comment below are
+// from FreeBSD's /usr/src/lib/msun/src/e_lgamma_r.c and
+// came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+// __ieee754_lgamma_r(x, signgamp)
+// Reentrant version of the logarithm of the Gamma function
+// with user provided pointer for the sign of Gamma(x).
+//
+// Method:
+// 1. Argument Reduction for 0 < x <= 8
+// Since gamma(1+s)=s*gamma(s), for x in [0,8], we may
+// reduce x to a number in [1.5,2.5] by
+// lgamma(1+s) = log(s) + lgamma(s)
+// for example,
+// lgamma(7.3) = log(6.3) + lgamma(6.3)
+// = log(6.3*5.3) + lgamma(5.3)
+// = log(6.3*5.3*4.3*3.3*2.3) + lgamma(2.3)
+// 2. Polynomial approximation of lgamma around its
+// minimum (ymin=1.461632144968362245) to maintain monotonicity.
+// On [ymin-0.23, ymin+0.27] (i.e., [1.23164,1.73163]), use
+// Let z = x-ymin;
+// lgamma(x) = -1.214862905358496078218 + z**2*poly(z)
+// poly(z) is a 14 degree polynomial.
+// 2. Rational approximation in the primary interval [2,3]
+// We use the following approximation:
+// s = x-2.0;
+// lgamma(x) = 0.5*s + s*P(s)/Q(s)
+// with accuracy
+// |P/Q - (lgamma(x)-0.5s)| < 2**-61.71
+// Our algorithms are based on the following observation
+//
+// zeta(2)-1 2 zeta(3)-1 3
+// lgamma(2+s) = s*(1-Euler) + --------- * s - --------- * s + ...
+// 2 3
+//
+// where Euler = 0.5772156649... is the Euler constant, which
+// is very close to 0.5.
+//
+// 3. For x>=8, we have
+// lgamma(x)~(x-0.5)log(x)-x+0.5*log(2pi)+1/(12x)-1/(360x**3)+....
+// (better formula:
+// lgamma(x)~(x-0.5)*(log(x)-1)-.5*(log(2pi)-1) + ...)
+// Let z = 1/x, then we approximation
+// f(z) = lgamma(x) - (x-0.5)(log(x)-1)
+// by
+// 3 5 11
+// w = w0 + w1*z + w2*z + w3*z + ... + w6*z
+// where
+// |w - f(z)| < 2**-58.74
+//
+// 4. For negative x, since (G is gamma function)
+// -x*G(-x)*G(x) = pi/sin(pi*x),
+// we have
+// G(x) = pi/(sin(pi*x)*(-x)*G(-x))
+// since G(-x) is positive, sign(G(x)) = sign(sin(pi*x)) for x<0
+// Hence, for x<0, signgam = sign(sin(pi*x)) and
+// lgamma(x) = log(|Gamma(x)|)
+// = log(pi/(|x*sin(pi*x)|)) - lgamma(-x);
+// Note: one should avoid computing pi*(-x) directly in the
+// computation of sin(pi*(-x)).
+//
+// 5. Special Cases
+// lgamma(2+s) ~ s*(1-Euler) for tiny s
+// lgamma(1)=lgamma(2)=0
+// lgamma(x) ~ -log(x) for tiny x
+// lgamma(0) = lgamma(inf) = inf
+// lgamma(-integer) = +-inf
+//
+//
+
+var _lgamA = [...]float64{
+ 7.72156649015328655494e-02, // 0x3FB3C467E37DB0C8
+ 3.22467033424113591611e-01, // 0x3FD4A34CC4A60FAD
+ 6.73523010531292681824e-02, // 0x3FB13E001A5562A7
+ 2.05808084325167332806e-02, // 0x3F951322AC92547B
+ 7.38555086081402883957e-03, // 0x3F7E404FB68FEFE8
+ 2.89051383673415629091e-03, // 0x3F67ADD8CCB7926B
+ 1.19270763183362067845e-03, // 0x3F538A94116F3F5D
+ 5.10069792153511336608e-04, // 0x3F40B6C689B99C00
+ 2.20862790713908385557e-04, // 0x3F2CF2ECED10E54D
+ 1.08011567247583939954e-04, // 0x3F1C5088987DFB07
+ 2.52144565451257326939e-05, // 0x3EFA7074428CFA52
+ 4.48640949618915160150e-05, // 0x3F07858E90A45837
+}
+var _lgamR = [...]float64{
+ 1.0, // placeholder
+ 1.39200533467621045958e+00, // 0x3FF645A762C4AB74
+ 7.21935547567138069525e-01, // 0x3FE71A1893D3DCDC
+ 1.71933865632803078993e-01, // 0x3FC601EDCCFBDF27
+ 1.86459191715652901344e-02, // 0x3F9317EA742ED475
+ 7.77942496381893596434e-04, // 0x3F497DDACA41A95B
+ 7.32668430744625636189e-06, // 0x3EDEBAF7A5B38140
+}
+var _lgamS = [...]float64{
+ -7.72156649015328655494e-02, // 0xBFB3C467E37DB0C8
+ 2.14982415960608852501e-01, // 0x3FCB848B36E20878
+ 3.25778796408930981787e-01, // 0x3FD4D98F4F139F59
+ 1.46350472652464452805e-01, // 0x3FC2BB9CBEE5F2F7
+ 2.66422703033638609560e-02, // 0x3F9B481C7E939961
+ 1.84028451407337715652e-03, // 0x3F5E26B67368F239
+ 3.19475326584100867617e-05, // 0x3F00BFECDD17E945
+}
+var _lgamT = [...]float64{
+ 4.83836122723810047042e-01, // 0x3FDEF72BC8EE38A2
+ -1.47587722994593911752e-01, // 0xBFC2E4278DC6C509
+ 6.46249402391333854778e-02, // 0x3FB08B4294D5419B
+ -3.27885410759859649565e-02, // 0xBFA0C9A8DF35B713
+ 1.79706750811820387126e-02, // 0x3F9266E7970AF9EC
+ -1.03142241298341437450e-02, // 0xBF851F9FBA91EC6A
+ 6.10053870246291332635e-03, // 0x3F78FCE0E370E344
+ -3.68452016781138256760e-03, // 0xBF6E2EFFB3E914D7
+ 2.25964780900612472250e-03, // 0x3F6282D32E15C915
+ -1.40346469989232843813e-03, // 0xBF56FE8EBF2D1AF1
+ 8.81081882437654011382e-04, // 0x3F4CDF0CEF61A8E9
+ -5.38595305356740546715e-04, // 0xBF41A6109C73E0EC
+ 3.15632070903625950361e-04, // 0x3F34AF6D6C0EBBF7
+ -3.12754168375120860518e-04, // 0xBF347F24ECC38C38
+ 3.35529192635519073543e-04, // 0x3F35FD3EE8C2D3F4
+}
+var _lgamU = [...]float64{
+ -7.72156649015328655494e-02, // 0xBFB3C467E37DB0C8
+ 6.32827064025093366517e-01, // 0x3FE4401E8B005DFF
+ 1.45492250137234768737e+00, // 0x3FF7475CD119BD6F
+ 9.77717527963372745603e-01, // 0x3FEF497644EA8450
+ 2.28963728064692451092e-01, // 0x3FCD4EAEF6010924
+ 1.33810918536787660377e-02, // 0x3F8B678BBF2BAB09
+}
+var _lgamV = [...]float64{
+ 1.0,
+ 2.45597793713041134822e+00, // 0x4003A5D7C2BD619C
+ 2.12848976379893395361e+00, // 0x40010725A42B18F5
+ 7.69285150456672783825e-01, // 0x3FE89DFBE45050AF
+ 1.04222645593369134254e-01, // 0x3FBAAE55D6537C88
+ 3.21709242282423911810e-03, // 0x3F6A5ABB57D0CF61
+}
+var _lgamW = [...]float64{
+ 4.18938533204672725052e-01, // 0x3FDACFE390C97D69
+ 8.33333333333329678849e-02, // 0x3FB555555555553B
+ -2.77777777728775536470e-03, // 0xBF66C16C16B02E5C
+ 7.93650558643019558500e-04, // 0x3F4A019F98CF38B6
+ -5.95187557450339963135e-04, // 0xBF4380CB8C0FE741
+ 8.36339918996282139126e-04, // 0x3F4B67BA4CDAD5D1
+ -1.63092934096575273989e-03, // 0xBF5AB89D0B9E43E4
+}
+
+// Lgamma returns the natural logarithm and sign (-1 or +1) of [Gamma](x).
+//
+// Special cases are:
+//
+// Lgamma(+Inf) = +Inf
+// Lgamma(0) = +Inf
+// Lgamma(-integer) = +Inf
+// Lgamma(-Inf) = -Inf
+// Lgamma(NaN) = NaN
+func Lgamma(x float64) (lgamma float64, sign int) {
+ const (
+ Ymin = 1.461632144968362245
+ Two52 = 1 << 52 // 0x4330000000000000 ~4.5036e+15
+ Two53 = 1 << 53 // 0x4340000000000000 ~9.0072e+15
+ Two58 = 1 << 58 // 0x4390000000000000 ~2.8823e+17
+ Tiny = 1.0 / (1 << 70) // 0x3b90000000000000 ~8.47033e-22
+ Tc = 1.46163214496836224576e+00 // 0x3FF762D86356BE3F
+ Tf = -1.21486290535849611461e-01 // 0xBFBF19B9BCC38A42
+ // Tt = -(tail of Tf)
+ Tt = -3.63867699703950536541e-18 // 0xBC50C7CAA48A971F
+ )
+ // special cases
+ sign = 1
+ switch {
+ case IsNaN(x):
+ lgamma = x
+ return
+ case IsInf(x, 0):
+ lgamma = x
+ return
+ case x == 0:
+ lgamma = Inf(1)
+ return
+ }
+
+ neg := false
+ if x < 0 {
+ x = -x
+ neg = true
+ }
+
+ if x < Tiny { // if |x| < 2**-70, return -log(|x|)
+ if neg {
+ sign = -1
+ }
+ lgamma = -Log(x)
+ return
+ }
+ var nadj float64
+ if neg {
+ if x >= Two52 { // |x| >= 2**52, must be -integer
+ lgamma = Inf(1)
+ return
+ }
+ t := sinPi(x)
+ if t == 0 {
+ lgamma = Inf(1) // -integer
+ return
+ }
+ nadj = Log(Pi / Abs(t*x))
+ if t < 0 {
+ sign = -1
+ }
+ }
+
+ switch {
+ case x == 1 || x == 2: // purge off 1 and 2
+ lgamma = 0
+ return
+ case x < 2: // use lgamma(x) = lgamma(x+1) - log(x)
+ var y float64
+ var i int
+ if x <= 0.9 {
+ lgamma = -Log(x)
+ switch {
+ case x >= (Ymin - 1 + 0.27): // 0.7316 <= x <= 0.9
+ y = 1 - x
+ i = 0
+ case x >= (Ymin - 1 - 0.27): // 0.2316 <= x < 0.7316
+ y = x - (Tc - 1)
+ i = 1
+ default: // 0 < x < 0.2316
+ y = x
+ i = 2
+ }
+ } else {
+ lgamma = 0
+ switch {
+ case x >= (Ymin + 0.27): // 1.7316 <= x < 2
+ y = 2 - x
+ i = 0
+ case x >= (Ymin - 0.27): // 1.2316 <= x < 1.7316
+ y = x - Tc
+ i = 1
+ default: // 0.9 < x < 1.2316
+ y = x - 1
+ i = 2
+ }
+ }
+ switch i {
+ case 0:
+ z := y * y
+ p1 := _lgamA[0] + z*(_lgamA[2]+z*(_lgamA[4]+z*(_lgamA[6]+z*(_lgamA[8]+z*_lgamA[10]))))
+ p2 := z * (_lgamA[1] + z*(+_lgamA[3]+z*(_lgamA[5]+z*(_lgamA[7]+z*(_lgamA[9]+z*_lgamA[11])))))
+ p := y*p1 + p2
+ lgamma += (p - 0.5*y)
+ case 1:
+ z := y * y
+ w := z * y
+ p1 := _lgamT[0] + w*(_lgamT[3]+w*(_lgamT[6]+w*(_lgamT[9]+w*_lgamT[12]))) // parallel comp
+ p2 := _lgamT[1] + w*(_lgamT[4]+w*(_lgamT[7]+w*(_lgamT[10]+w*_lgamT[13])))
+ p3 := _lgamT[2] + w*(_lgamT[5]+w*(_lgamT[8]+w*(_lgamT[11]+w*_lgamT[14])))
+ p := z*p1 - (Tt - w*(p2+y*p3))
+ lgamma += (Tf + p)
+ case 2:
+ p1 := y * (_lgamU[0] + y*(_lgamU[1]+y*(_lgamU[2]+y*(_lgamU[3]+y*(_lgamU[4]+y*_lgamU[5])))))
+ p2 := 1 + y*(_lgamV[1]+y*(_lgamV[2]+y*(_lgamV[3]+y*(_lgamV[4]+y*_lgamV[5]))))
+ lgamma += (-0.5*y + p1/p2)
+ }
+ case x < 8: // 2 <= x < 8
+ i := int(x)
+ y := x - float64(i)
+ p := y * (_lgamS[0] + y*(_lgamS[1]+y*(_lgamS[2]+y*(_lgamS[3]+y*(_lgamS[4]+y*(_lgamS[5]+y*_lgamS[6]))))))
+ q := 1 + y*(_lgamR[1]+y*(_lgamR[2]+y*(_lgamR[3]+y*(_lgamR[4]+y*(_lgamR[5]+y*_lgamR[6])))))
+ lgamma = 0.5*y + p/q
+ z := 1.0 // Lgamma(1+s) = Log(s) + Lgamma(s)
+ switch i {
+ case 7:
+ z *= (y + 6)
+ fallthrough
+ case 6:
+ z *= (y + 5)
+ fallthrough
+ case 5:
+ z *= (y + 4)
+ fallthrough
+ case 4:
+ z *= (y + 3)
+ fallthrough
+ case 3:
+ z *= (y + 2)
+ lgamma += Log(z)
+ }
+ case x < Two58: // 8 <= x < 2**58
+ t := Log(x)
+ z := 1 / x
+ y := z * z
+ w := _lgamW[0] + z*(_lgamW[1]+y*(_lgamW[2]+y*(_lgamW[3]+y*(_lgamW[4]+y*(_lgamW[5]+y*_lgamW[6])))))
+ lgamma = (x-0.5)*(t-1) + w
+ default: // 2**58 <= x <= Inf
+ lgamma = x * (Log(x) - 1)
+ }
+ if neg {
+ lgamma = nadj - lgamma
+ }
+ return
+}
+
+// sinPi(x) is a helper function for negative x
+func sinPi(x float64) float64 {
+ const (
+ Two52 = 1 << 52 // 0x4330000000000000 ~4.5036e+15
+ Two53 = 1 << 53 // 0x4340000000000000 ~9.0072e+15
+ )
+ if x < 0.25 {
+ return -Sin(Pi * x)
+ }
+
+ // argument reduction
+ z := Floor(x)
+ var n int
+ if z != x { // inexact
+ x = Mod(x, 2)
+ n = int(x * 4)
+ } else {
+ if x >= Two53 { // x must be even
+ x = 0
+ n = 0
+ } else {
+ if x < Two52 {
+ z = x + Two52 // exact
+ }
+ n = int(1 & Float64bits(z))
+ x = float64(n)
+ n <<= 2
+ }
+ }
+ switch n {
+ case 0:
+ x = Sin(Pi * x)
+ case 1, 2:
+ x = Cos(Pi * (0.5 - x))
+ case 3, 4:
+ x = Sin(Pi * (1 - x))
+ case 5, 6:
+ x = -Cos(Pi * (x - 1.5))
+ default:
+ x = Sin(Pi * (x - 2))
+ }
+ return -x
+}
diff --git a/go/src/math/log.go b/go/src/math/log.go
new file mode 100644
index 0000000000000000000000000000000000000000..695a545e7f00ec23ccf024e91c6172a454613fe4
--- /dev/null
+++ b/go/src/math/log.go
@@ -0,0 +1,129 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+ Floating-point logarithm.
+*/
+
+// The original C code, the long comment, and the constants
+// below are from FreeBSD's /usr/src/lib/msun/src/e_log.c
+// and came with this notice. The go code is a simpler
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+// __ieee754_log(x)
+// Return the logarithm of x
+//
+// Method :
+// 1. Argument Reduction: find k and f such that
+// x = 2**k * (1+f),
+// where sqrt(2)/2 < 1+f < sqrt(2) .
+//
+// 2. Approximation of log(1+f).
+// Let s = f/(2+f) ; based on log(1+f) = log(1+s) - log(1-s)
+// = 2s + 2/3 s**3 + 2/5 s**5 + .....,
+// = 2s + s*R
+// We use a special Reme algorithm on [0,0.1716] to generate
+// a polynomial of degree 14 to approximate R. The maximum error
+// of this polynomial approximation is bounded by 2**-58.45. In
+// other words,
+// 2 4 6 8 10 12 14
+// R(z) ~ L1*s +L2*s +L3*s +L4*s +L5*s +L6*s +L7*s
+// (the values of L1 to L7 are listed in the program) and
+// | 2 14 | -58.45
+// | L1*s +...+L7*s - R(z) | <= 2
+// | |
+// Note that 2s = f - s*f = f - hfsq + s*hfsq, where hfsq = f*f/2.
+// In order to guarantee error in log below 1ulp, we compute log by
+// log(1+f) = f - s*(f - R) (if f is not too large)
+// log(1+f) = f - (hfsq - s*(hfsq+R)). (better accuracy)
+//
+// 3. Finally, log(x) = k*Ln2 + log(1+f).
+// = k*Ln2_hi+(f-(hfsq-(s*(hfsq+R)+k*Ln2_lo)))
+// Here Ln2 is split into two floating point number:
+// Ln2_hi + Ln2_lo,
+// where n*Ln2_hi is always exact for |n| < 2000.
+//
+// Special cases:
+// log(x) is NaN with signal if x < 0 (including -INF) ;
+// log(+INF) is +INF; log(0) is -INF with signal;
+// log(NaN) is that NaN with no signal.
+//
+// Accuracy:
+// according to an error analysis, the error is always less than
+// 1 ulp (unit in the last place).
+//
+// Constants:
+// The hexadecimal values are the intended ones for the following
+// constants. The decimal values may be used, provided that the
+// compiler will convert from decimal to binary accurately enough
+// to produce the hexadecimal values shown.
+
+// Log returns the natural logarithm of x.
+//
+// Special cases are:
+//
+// Log(+Inf) = +Inf
+// Log(0) = -Inf
+// Log(x < 0) = NaN
+// Log(NaN) = NaN
+func Log(x float64) float64 {
+ if haveArchLog {
+ return archLog(x)
+ }
+ return log(x)
+}
+
+func log(x float64) float64 {
+ const (
+ Ln2Hi = 6.93147180369123816490e-01 /* 3fe62e42 fee00000 */
+ Ln2Lo = 1.90821492927058770002e-10 /* 3dea39ef 35793c76 */
+ L1 = 6.666666666666735130e-01 /* 3FE55555 55555593 */
+ L2 = 3.999999999940941908e-01 /* 3FD99999 9997FA04 */
+ L3 = 2.857142874366239149e-01 /* 3FD24924 94229359 */
+ L4 = 2.222219843214978396e-01 /* 3FCC71C5 1D8E78AF */
+ L5 = 1.818357216161805012e-01 /* 3FC74664 96CB03DE */
+ L6 = 1.531383769920937332e-01 /* 3FC39A09 D078C69F */
+ L7 = 1.479819860511658591e-01 /* 3FC2F112 DF3E5244 */
+ )
+
+ // special cases
+ switch {
+ case IsNaN(x) || IsInf(x, 1):
+ return x
+ case x < 0:
+ return NaN()
+ case x == 0:
+ return Inf(-1)
+ }
+
+ // reduce
+ f1, ki := Frexp(x)
+ if f1 < Sqrt2/2 {
+ f1 *= 2
+ ki--
+ }
+ f := f1 - 1
+ k := float64(ki)
+
+ // compute
+ s := f / (2 + f)
+ s2 := s * s
+ s4 := s2 * s2
+ t1 := s2 * (L1 + s4*(L3+s4*(L5+s4*L7)))
+ t2 := s4 * (L2 + s4*(L4+s4*L6))
+ R := t1 + t2
+ hfsq := 0.5 * f * f
+ return k*Ln2Hi - ((hfsq - (s*(hfsq+R) + k*Ln2Lo)) - f)
+}
diff --git a/go/src/math/log10.go b/go/src/math/log10.go
new file mode 100644
index 0000000000000000000000000000000000000000..02c3a757c012be60ff3654fe063364390b8b947a
--- /dev/null
+++ b/go/src/math/log10.go
@@ -0,0 +1,37 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Log10 returns the decimal logarithm of x.
+// The special cases are the same as for [Log].
+func Log10(x float64) float64 {
+ if haveArchLog10 {
+ return archLog10(x)
+ }
+ return log10(x)
+}
+
+func log10(x float64) float64 {
+ return Log(x) * (1 / Ln10)
+}
+
+// Log2 returns the binary logarithm of x.
+// The special cases are the same as for [Log].
+func Log2(x float64) float64 {
+ if haveArchLog2 {
+ return archLog2(x)
+ }
+ return log2(x)
+}
+
+func log2(x float64) float64 {
+ frac, exp := Frexp(x)
+ // Make sure exact powers of two give an exact answer.
+ // Don't depend on Log(0.5)*(1/Ln2)+exp being exactly exp-1.
+ if frac == 0.5 {
+ return float64(exp - 1)
+ }
+ return Log(frac)*(1/Ln2) + float64(exp)
+}
diff --git a/go/src/math/log10_s390x.s b/go/src/math/log10_s390x.s
new file mode 100644
index 0000000000000000000000000000000000000000..3638afe700df47ad95aa2bc16c9e07ed5ee04b23
--- /dev/null
+++ b/go/src/math/log10_s390x.s
@@ -0,0 +1,156 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// Minimax polynomial coefficients and other constants
+DATA log10rodataL19<>+0(SB)/8, $0.000000000000000000E+00
+DATA log10rodataL19<>+8(SB)/8, $-1.0
+DATA log10rodataL19<>+16(SB)/8, $0x7FF8000000000000 //+NanN
+DATA log10rodataL19<>+24(SB)/8, $.15375570329280596749
+DATA log10rodataL19<>+32(SB)/8, $.60171950900703668594E+04
+DATA log10rodataL19<>+40(SB)/8, $-1.9578460454940795898
+DATA log10rodataL19<>+48(SB)/8, $0.78962633073318517310E-01
+DATA log10rodataL19<>+56(SB)/8, $-.71784211884836937993E-02
+DATA log10rodataL19<>+64(SB)/8, $0.87011165920689940661E-03
+DATA log10rodataL19<>+72(SB)/8, $-.11865158981621437541E-03
+DATA log10rodataL19<>+80(SB)/8, $0.17258413403018680410E-04
+DATA log10rodataL19<>+88(SB)/8, $0.40752932047883484315E-06
+DATA log10rodataL19<>+96(SB)/8, $-.26149194688832680410E-05
+DATA log10rodataL19<>+104(SB)/8, $0.92453396963875026759E-08
+DATA log10rodataL19<>+112(SB)/8, $-.64572084905921579630E-07
+DATA log10rodataL19<>+120(SB)/8, $-5.5
+DATA log10rodataL19<>+128(SB)/8, $18446744073709551616.
+GLOBL log10rodataL19<>+0(SB), RODATA, $136
+
+// Table of log10 correction terms
+DATA log10tab2074<>+0(SB)/8, $0.254164497922885069E-01
+DATA log10tab2074<>+8(SB)/8, $0.179018857989381839E-01
+DATA log10tab2074<>+16(SB)/8, $0.118926768029048674E-01
+DATA log10tab2074<>+24(SB)/8, $0.722595568238080033E-02
+DATA log10tab2074<>+32(SB)/8, $0.376393570022739135E-02
+DATA log10tab2074<>+40(SB)/8, $0.138901135928814326E-02
+DATA log10tab2074<>+48(SB)/8, $0
+DATA log10tab2074<>+56(SB)/8, $-0.490780466387818203E-03
+DATA log10tab2074<>+64(SB)/8, $-0.159811431402137571E-03
+DATA log10tab2074<>+72(SB)/8, $0.925796337165100494E-03
+DATA log10tab2074<>+80(SB)/8, $0.270683176738357035E-02
+DATA log10tab2074<>+88(SB)/8, $0.513079030821304758E-02
+DATA log10tab2074<>+96(SB)/8, $0.815089785397996303E-02
+DATA log10tab2074<>+104(SB)/8, $0.117253060262419215E-01
+DATA log10tab2074<>+112(SB)/8, $0.158164239345343963E-01
+DATA log10tab2074<>+120(SB)/8, $0.203903595489229786E-01
+GLOBL log10tab2074<>+0(SB), RODATA, $128
+
+// Log10 returns the decimal logarithm of the argument.
+//
+// Special cases are:
+// Log(+Inf) = +Inf
+// Log(0) = -Inf
+// Log(x < 0) = NaN
+// Log(NaN) = NaN
+// The algorithm used is minimax polynomial approximation
+// with coefficients determined with a Remez exchange algorithm.
+
+TEXT ·log10Asm(SB),NOSPLIT,$8-16
+ FMOVD x+0(FP), F0
+ MOVD $log10rodataL19<>+0(SB), R9
+ FMOVD F0, x-8(SP)
+ WORD $0xC0298006 //iilf %r2,2147909631
+ BYTE $0x7F
+ BYTE $0xFF
+ WORD $0x5840F008 //l %r4, 8(%r15)
+ SUBW R4, R2, R3
+ RISBGZ $32, $47, $0, R3, R5
+ MOVH $0x0, R1
+ RISBGN $0, $31, $32, R5, R1
+ WORD $0xC0590016 //iilf %r5,1507327
+ BYTE $0xFF
+ BYTE $0xFF
+ MOVW R4, R10
+ MOVW R5, R11
+ CMPBLE R10, R11, L2
+ WORD $0xC0297FEF //iilf %r2,2146435071
+ BYTE $0xFF
+ BYTE $0xFF
+ MOVW R4, R10
+ MOVW R2, R11
+ CMPBLE R10, R11, L16
+L3:
+L1:
+ FMOVD F0, ret+8(FP)
+ RET
+
+L2:
+ LTDBR F0, F0
+ BLEU L13
+ WORD $0xED009080 //mdb %f0,.L20-.L19(%r9)
+ BYTE $0x00
+ BYTE $0x1C
+ FMOVD F0, x-8(SP)
+ WORD $0x5B20F008 //s %r2, 8(%r15)
+ RISBGZ $57, $60, $51, R2, R3
+ ANDW $0xFFFF0000, R2
+ RISBGN $0, $31, $32, R2, R1
+ ADDW $0x4000000, R2
+ BLEU L17
+L8:
+ SRW $8, R2, R2
+ ORW $0x45000000, R2
+L4:
+ FMOVD log10rodataL19<>+120(SB), F2
+ LDGR R1, F4
+ WFMADB V4, V0, V2, V0
+ FMOVD log10rodataL19<>+112(SB), F4
+ FMOVD log10rodataL19<>+104(SB), F6
+ WFMADB V0, V6, V4, V6
+ FMOVD log10rodataL19<>+96(SB), F4
+ FMOVD log10rodataL19<>+88(SB), F1
+ WFMADB V0, V1, V4, V1
+ WFMDB V0, V0, V4
+ FMOVD log10rodataL19<>+80(SB), F2
+ WFMADB V6, V4, V1, V6
+ FMOVD log10rodataL19<>+72(SB), F1
+ WFMADB V0, V2, V1, V2
+ FMOVD log10rodataL19<>+64(SB), F1
+ RISBGZ $57, $60, $0, R3, R3
+ WFMADB V4, V6, V2, V6
+ FMOVD log10rodataL19<>+56(SB), F2
+ WFMADB V0, V1, V2, V1
+ VLVGF $0, R2, V2
+ WFMADB V4, V6, V1, V4
+ LDEBR F2, F2
+ FMOVD log10rodataL19<>+48(SB), F6
+ WFMADB V0, V4, V6, V4
+ FMOVD log10rodataL19<>+40(SB), F1
+ FMOVD log10rodataL19<>+32(SB), F6
+ MOVD $log10tab2074<>+0(SB), R1
+ WFMADB V2, V1, V6, V2
+ WORD $0x68331000 //ld %f3,0(%r3,%r1)
+ WFMADB V0, V4, V3, V0
+ FMOVD log10rodataL19<>+24(SB), F4
+ FMADD F4, F2, F0
+ FMOVD F0, ret+8(FP)
+ RET
+
+L16:
+ RISBGZ $40, $55, $56, R3, R2
+ RISBGZ $57, $60, $51, R3, R3
+ ORW $0x45000000, R2
+ BR L4
+L13:
+ BGE L18 //jnl .L18
+ BVS L18
+ FMOVD log10rodataL19<>+16(SB), F0
+ BR L1
+L17:
+ SRAW $1, R2, R2
+ SUBW $0x40000000, R2
+ BR L8
+L18:
+ FMOVD log10rodataL19<>+8(SB), F0
+ WORD $0xED009000 //ddb %f0,.L36-.L19(%r9)
+ BYTE $0x00
+ BYTE $0x1D
+ BR L1
diff --git a/go/src/math/log1p.go b/go/src/math/log1p.go
new file mode 100644
index 0000000000000000000000000000000000000000..bfcb813be8ceeccd197e374fdfb2595cc41346fe
--- /dev/null
+++ b/go/src/math/log1p.go
@@ -0,0 +1,203 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// The original C code, the long comment, and the constants
+// below are from FreeBSD's /usr/src/lib/msun/src/s_log1p.c
+// and came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+//
+// double log1p(double x)
+//
+// Method :
+// 1. Argument Reduction: find k and f such that
+// 1+x = 2**k * (1+f),
+// where sqrt(2)/2 < 1+f < sqrt(2) .
+//
+// Note. If k=0, then f=x is exact. However, if k!=0, then f
+// may not be representable exactly. In that case, a correction
+// term is need. Let u=1+x rounded. Let c = (1+x)-u, then
+// log(1+x) - log(u) ~ c/u. Thus, we proceed to compute log(u),
+// and add back the correction term c/u.
+// (Note: when x > 2**53, one can simply return log(x))
+//
+// 2. Approximation of log1p(f).
+// Let s = f/(2+f) ; based on log(1+f) = log(1+s) - log(1-s)
+// = 2s + 2/3 s**3 + 2/5 s**5 + .....,
+// = 2s + s*R
+// We use a special Reme algorithm on [0,0.1716] to generate
+// a polynomial of degree 14 to approximate R The maximum error
+// of this polynomial approximation is bounded by 2**-58.45. In
+// other words,
+// 2 4 6 8 10 12 14
+// R(z) ~ Lp1*s +Lp2*s +Lp3*s +Lp4*s +Lp5*s +Lp6*s +Lp7*s
+// (the values of Lp1 to Lp7 are listed in the program)
+// and
+// | 2 14 | -58.45
+// | Lp1*s +...+Lp7*s - R(z) | <= 2
+// | |
+// Note that 2s = f - s*f = f - hfsq + s*hfsq, where hfsq = f*f/2.
+// In order to guarantee error in log below 1ulp, we compute log
+// by
+// log1p(f) = f - (hfsq - s*(hfsq+R)).
+//
+// 3. Finally, log1p(x) = k*ln2 + log1p(f).
+// = k*ln2_hi+(f-(hfsq-(s*(hfsq+R)+k*ln2_lo)))
+// Here ln2 is split into two floating point number:
+// ln2_hi + ln2_lo,
+// where n*ln2_hi is always exact for |n| < 2000.
+//
+// Special cases:
+// log1p(x) is NaN with signal if x < -1 (including -INF) ;
+// log1p(+INF) is +INF; log1p(-1) is -INF with signal;
+// log1p(NaN) is that NaN with no signal.
+//
+// Accuracy:
+// according to an error analysis, the error is always less than
+// 1 ulp (unit in the last place).
+//
+// Constants:
+// The hexadecimal values are the intended ones for the following
+// constants. The decimal values may be used, provided that the
+// compiler will convert from decimal to binary accurately enough
+// to produce the hexadecimal values shown.
+//
+// Note: Assuming log() return accurate answer, the following
+// algorithm can be used to compute log1p(x) to within a few ULP:
+//
+// u = 1+x;
+// if(u==1.0) return x ; else
+// return log(u)*(x/(u-1.0));
+//
+// See HP-15C Advanced Functions Handbook, p.193.
+
+// Log1p returns the natural logarithm of 1 plus its argument x.
+// It is more accurate than [Log](1 + x) when x is near zero.
+//
+// Special cases are:
+//
+// Log1p(+Inf) = +Inf
+// Log1p(±0) = ±0
+// Log1p(-1) = -Inf
+// Log1p(x < -1) = NaN
+// Log1p(NaN) = NaN
+func Log1p(x float64) float64 {
+ if haveArchLog1p {
+ return archLog1p(x)
+ }
+ return log1p(x)
+}
+
+func log1p(x float64) float64 {
+ const (
+ Sqrt2M1 = 4.142135623730950488017e-01 // Sqrt(2)-1 = 0x3fda827999fcef34
+ Sqrt2HalfM1 = -2.928932188134524755992e-01 // Sqrt(2)/2-1 = 0xbfd2bec333018866
+ Small = 1.0 / (1 << 29) // 2**-29 = 0x3e20000000000000
+ Tiny = 1.0 / (1 << 54) // 2**-54
+ Two53 = 1 << 53 // 2**53
+ Ln2Hi = 6.93147180369123816490e-01 // 3fe62e42fee00000
+ Ln2Lo = 1.90821492927058770002e-10 // 3dea39ef35793c76
+ Lp1 = 6.666666666666735130e-01 // 3FE5555555555593
+ Lp2 = 3.999999999940941908e-01 // 3FD999999997FA04
+ Lp3 = 2.857142874366239149e-01 // 3FD2492494229359
+ Lp4 = 2.222219843214978396e-01 // 3FCC71C51D8E78AF
+ Lp5 = 1.818357216161805012e-01 // 3FC7466496CB03DE
+ Lp6 = 1.531383769920937332e-01 // 3FC39A09D078C69F
+ Lp7 = 1.479819860511658591e-01 // 3FC2F112DF3E5244
+ )
+
+ // special cases
+ switch {
+ case x < -1 || IsNaN(x): // includes -Inf
+ return NaN()
+ case x == -1:
+ return Inf(-1)
+ case IsInf(x, 1):
+ return Inf(1)
+ }
+
+ absx := Abs(x)
+
+ var f float64
+ var iu uint64
+ k := 1
+ if absx < Sqrt2M1 { // |x| < Sqrt(2)-1
+ if absx < Small { // |x| < 2**-29
+ if absx < Tiny { // |x| < 2**-54
+ return x
+ }
+ return x - x*x*0.5
+ }
+ if x > Sqrt2HalfM1 { // Sqrt(2)/2-1 < x
+ // (Sqrt(2)/2-1) < x < (Sqrt(2)-1)
+ k = 0
+ f = x
+ iu = 1
+ }
+ }
+ var c float64
+ if k != 0 {
+ var u float64
+ if absx < Two53 { // 1<<53
+ u = 1.0 + x
+ iu = Float64bits(u)
+ k = int((iu >> 52) - 1023)
+ // correction term
+ if k > 0 {
+ c = 1.0 - (u - x)
+ } else {
+ c = x - (u - 1.0)
+ }
+ c /= u
+ } else {
+ u = x
+ iu = Float64bits(u)
+ k = int((iu >> 52) - 1023)
+ c = 0
+ }
+ iu &= 0x000fffffffffffff
+ if iu < 0x0006a09e667f3bcd { // mantissa of Sqrt(2)
+ u = Float64frombits(iu | 0x3ff0000000000000) // normalize u
+ } else {
+ k++
+ u = Float64frombits(iu | 0x3fe0000000000000) // normalize u/2
+ iu = (0x0010000000000000 - iu) >> 2
+ }
+ f = u - 1.0 // Sqrt(2)/2 < u < Sqrt(2)
+ }
+ hfsq := 0.5 * f * f
+ var s, R, z float64
+ if iu == 0 { // |f| < 2**-20
+ if f == 0 {
+ if k == 0 {
+ return 0
+ }
+ c += float64(k) * Ln2Lo
+ return float64(k)*Ln2Hi + c
+ }
+ R = hfsq * (1.0 - 0.66666666666666666*f) // avoid division
+ if k == 0 {
+ return f - R
+ }
+ return float64(k)*Ln2Hi - ((R - (float64(k)*Ln2Lo + c)) - f)
+ }
+ s = f / (2.0 + f)
+ z = s * s
+ R = z * (Lp1 + z*(Lp2+z*(Lp3+z*(Lp4+z*(Lp5+z*(Lp6+z*Lp7))))))
+ if k == 0 {
+ return f - (hfsq - s*(hfsq+R))
+ }
+ return float64(k)*Ln2Hi - ((hfsq - (s*(hfsq+R) + (float64(k)*Ln2Lo + c))) - f)
+}
diff --git a/go/src/math/log1p_s390x.s b/go/src/math/log1p_s390x.s
new file mode 100644
index 0000000000000000000000000000000000000000..98fe82c9c390029aebab7474bdcb536c1a414c2c
--- /dev/null
+++ b/go/src/math/log1p_s390x.s
@@ -0,0 +1,180 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// Constants
+DATA ·log1pxlim<> + 0(SB)/4, $0xfff00000
+GLOBL ·log1pxlim<> + 0(SB), RODATA, $4
+DATA ·log1pxzero<> + 0(SB)/8, $0.0
+GLOBL ·log1pxzero<> + 0(SB), RODATA, $8
+DATA ·log1pxminf<> + 0(SB)/8, $0xfff0000000000000
+GLOBL ·log1pxminf<> + 0(SB), RODATA, $8
+DATA ·log1pxnan<> + 0(SB)/8, $0x7ff8000000000000
+GLOBL ·log1pxnan<> + 0(SB), RODATA, $8
+DATA ·log1pyout<> + 0(SB)/8, $0x40fce621e71da000
+GLOBL ·log1pyout<> + 0(SB), RODATA, $8
+DATA ·log1pxout<> + 0(SB)/8, $0x40f1000000000000
+GLOBL ·log1pxout<> + 0(SB), RODATA, $8
+DATA ·log1pxl2<> + 0(SB)/8, $0xbfda7aecbeba4e46
+GLOBL ·log1pxl2<> + 0(SB), RODATA, $8
+DATA ·log1pxl1<> + 0(SB)/8, $0x3ffacde700000000
+GLOBL ·log1pxl1<> + 0(SB), RODATA, $8
+DATA ·log1pxa<> + 0(SB)/8, $5.5
+GLOBL ·log1pxa<> + 0(SB), RODATA, $8
+DATA ·log1pxmone<> + 0(SB)/8, $-1.0
+GLOBL ·log1pxmone<> + 0(SB), RODATA, $8
+
+// Minimax polynomial approximations
+DATA ·log1pc8<> + 0(SB)/8, $0.212881813645679599E-07
+GLOBL ·log1pc8<> + 0(SB), RODATA, $8
+DATA ·log1pc7<> + 0(SB)/8, $-.148682720127920854E-06
+GLOBL ·log1pc7<> + 0(SB), RODATA, $8
+DATA ·log1pc6<> + 0(SB)/8, $0.938370938292558173E-06
+GLOBL ·log1pc6<> + 0(SB), RODATA, $8
+DATA ·log1pc5<> + 0(SB)/8, $-.602107458843052029E-05
+GLOBL ·log1pc5<> + 0(SB), RODATA, $8
+DATA ·log1pc4<> + 0(SB)/8, $0.397389654305194527E-04
+GLOBL ·log1pc4<> + 0(SB), RODATA, $8
+DATA ·log1pc3<> + 0(SB)/8, $-.273205381970859341E-03
+GLOBL ·log1pc3<> + 0(SB), RODATA, $8
+DATA ·log1pc2<> + 0(SB)/8, $0.200350613573012186E-02
+GLOBL ·log1pc2<> + 0(SB), RODATA, $8
+DATA ·log1pc1<> + 0(SB)/8, $-.165289256198351540E-01
+GLOBL ·log1pc1<> + 0(SB), RODATA, $8
+DATA ·log1pc0<> + 0(SB)/8, $0.181818181818181826E+00
+GLOBL ·log1pc0<> + 0(SB), RODATA, $8
+
+
+// Table of log10 correction terms
+DATA ·log1ptab<> + 0(SB)/8, $0.585235384085551248E-01
+DATA ·log1ptab<> + 8(SB)/8, $0.412206153771168640E-01
+DATA ·log1ptab<> + 16(SB)/8, $0.273839003221648339E-01
+DATA ·log1ptab<> + 24(SB)/8, $0.166383778368856480E-01
+DATA ·log1ptab<> + 32(SB)/8, $0.866678223433169637E-02
+DATA ·log1ptab<> + 40(SB)/8, $0.319831684989627514E-02
+DATA ·log1ptab<> + 48(SB)/8, $-.000000000000000000E+00
+DATA ·log1ptab<> + 56(SB)/8, $-.113006378583725549E-02
+DATA ·log1ptab<> + 64(SB)/8, $-.367979419636602491E-03
+DATA ·log1ptab<> + 72(SB)/8, $0.213172484510484979E-02
+DATA ·log1ptab<> + 80(SB)/8, $0.623271047682013536E-02
+DATA ·log1ptab<> + 88(SB)/8, $0.118140812789696885E-01
+DATA ·log1ptab<> + 96(SB)/8, $0.187681358930914206E-01
+DATA ·log1ptab<> + 104(SB)/8, $0.269985148668178992E-01
+DATA ·log1ptab<> + 112(SB)/8, $0.364186619761331328E-01
+DATA ·log1ptab<> + 120(SB)/8, $0.469505379381388441E-01
+GLOBL ·log1ptab<> + 0(SB), RODATA, $128
+
+// Log1p returns the natural logarithm of 1 plus its argument x.
+// It is more accurate than Log(1 + x) when x is near zero.
+//
+// Special cases are:
+// Log1p(+Inf) = +Inf
+// Log1p(±0) = ±0
+// Log1p(-1) = -Inf
+// Log1p(x < -1) = NaN
+// Log1p(NaN) = NaN
+// The algorithm used is minimax polynomial approximation
+// with coefficients determined with a Remez exchange algorithm.
+
+TEXT ·log1pAsm(SB), NOSPLIT, $0-16
+ FMOVD x+0(FP), F0
+ MOVD $·log1pxmone<>+0(SB), R1
+ MOVD ·log1pxout<>+0(SB), R2
+ FMOVD 0(R1), F3
+ MOVD $·log1pxa<>+0(SB), R1
+ MOVWZ ·log1pxlim<>+0(SB), R0
+ FMOVD 0(R1), F1
+ MOVD $·log1pc8<>+0(SB), R1
+ FMOVD 0(R1), F5
+ MOVD $·log1pc7<>+0(SB), R1
+ VLEG $0, 0(R1), V20
+ MOVD $·log1pc6<>+0(SB), R1
+ WFSDB V0, V3, V4
+ VLEG $0, 0(R1), V18
+ MOVD $·log1pc5<>+0(SB), R1
+ VLEG $0, 0(R1), V16
+ MOVD R2, R5
+ LGDR F4, R3
+ WORD $0xC0190006 //iilf %r1,425983
+ BYTE $0x7F
+ BYTE $0xFF
+ SRAD $32, R3, R3
+ SUBW R3, R1
+ SRW $16, R1, R1
+ BYTE $0x18 //lr %r4,%r1
+ BYTE $0x41
+ RISBGN $0, $15, $48, R4, R2
+ RISBGN $16, $31, $32, R4, R5
+ MOVW R0, R6
+ MOVW R3, R7
+ CMPBGT R6, R7, L8
+ WFCEDBS V4, V4, V6
+ MOVD $·log1pxzero<>+0(SB), R1
+ FMOVD 0(R1), F2
+ BVS LEXITTAGlog1p
+ LCDBR F4, F4
+ WFCEDBS V2, V4, V6
+ BEQ L9
+ WFCHDBS V4, V2, V2
+ BEQ LEXITTAGlog1p
+ MOVD $·log1pxnan<>+0(SB), R1
+ FMOVD 0(R1), F0
+ FMOVD F0, ret+8(FP)
+ RET
+
+L8:
+ LDGR R2, F2
+ FSUB F4, F3
+ FMADD F2, F4, F1
+ MOVD $·log1pc4<>+0(SB), R2
+ LCDBR F1, F4
+ FMOVD 0(R2), F7
+ FSUB F3, F0
+ MOVD $·log1pc3<>+0(SB), R2
+ FMOVD 0(R2), F3
+ MOVD $·log1pc2<>+0(SB), R2
+ WFMDB V1, V1, V6
+ FMADD F7, F4, F3
+ WFMSDB V0, V2, V1, V0
+ FMOVD 0(R2), F7
+ WFMADB V4, V5, V20, V5
+ MOVD $·log1pc1<>+0(SB), R2
+ FMOVD 0(R2), F2
+ FMADD F7, F4, F2
+ WFMADB V4, V18, V16, V4
+ FMADD F3, F6, F2
+ WFMADB V5, V6, V4, V5
+ FMUL F6, F6
+ MOVD $·log1pc0<>+0(SB), R2
+ WFMADB V6, V5, V2, V6
+ FMOVD 0(R2), F4
+ WFMADB V0, V6, V4, V6
+ RISBGZ $57, $60, $3, R1, R1
+ MOVD $·log1ptab<>+0(SB), R2
+ MOVD $·log1pxl1<>+0(SB), R3
+ WORD $0x68112000 //ld %f1,0(%r1,%r2)
+ FMOVD 0(R3), F2
+ WFMADB V0, V6, V1, V0
+ MOVD $·log1pyout<>+0(SB), R1
+ LDGR R5, F6
+ FMOVD 0(R1), F4
+ WFMSDB V2, V6, V4, V2
+ MOVD $·log1pxl2<>+0(SB), R1
+ FMOVD 0(R1), F4
+ FMADD F4, F2, F0
+ FMOVD F0, ret+8(FP)
+ RET
+
+L9:
+ MOVD $·log1pxminf<>+0(SB), R1
+ FMOVD 0(R1), F0
+ FMOVD F0, ret+8(FP)
+ RET
+
+
+LEXITTAGlog1p:
+ FMOVD F0, ret+8(FP)
+ RET
+
diff --git a/go/src/math/log_amd64.s b/go/src/math/log_amd64.s
new file mode 100644
index 0000000000000000000000000000000000000000..508df68a9bddce0ced5e6017934679b581704620
--- /dev/null
+++ b/go/src/math/log_amd64.s
@@ -0,0 +1,112 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+#define HSqrt2 7.07106781186547524401e-01 // sqrt(2)/2
+#define Ln2Hi 6.93147180369123816490e-01 // 0x3fe62e42fee00000
+#define Ln2Lo 1.90821492927058770002e-10 // 0x3dea39ef35793c76
+#define L1 6.666666666666735130e-01 // 0x3FE5555555555593
+#define L2 3.999999999940941908e-01 // 0x3FD999999997FA04
+#define L3 2.857142874366239149e-01 // 0x3FD2492494229359
+#define L4 2.222219843214978396e-01 // 0x3FCC71C51D8E78AF
+#define L5 1.818357216161805012e-01 // 0x3FC7466496CB03DE
+#define L6 1.531383769920937332e-01 // 0x3FC39A09D078C69F
+#define L7 1.479819860511658591e-01 // 0x3FC2F112DF3E5244
+#define NaN 0x7FF8000000000001
+#define NegInf 0xFFF0000000000000
+#define PosInf 0x7FF0000000000000
+
+// func Log(x float64) float64
+TEXT ·archLog(SB),NOSPLIT,$0
+ // test bits for special cases
+ MOVQ x+0(FP), BX
+ MOVQ $~(1<<63), AX // sign bit mask
+ ANDQ BX, AX
+ JEQ isZero
+ MOVQ $0, AX
+ CMPQ AX, BX
+ JGT isNegative
+ MOVQ $PosInf, AX
+ CMPQ AX, BX
+ JLE isInfOrNaN
+ // f1, ki := math.Frexp(x); k := float64(ki)
+ MOVQ BX, X0
+ MOVQ $0x000FFFFFFFFFFFFF, AX
+ MOVQ AX, X2
+ ANDPD X0, X2
+ MOVSD $0.5, X0 // 0x3FE0000000000000
+ ORPD X0, X2 // X2= f1
+ SHRQ $52, BX
+ ANDL $0x7FF, BX
+ SUBL $0x3FE, BX
+ XORPS X1, X1 // break dependency for CVTSL2SD
+ CVTSL2SD BX, X1 // x1= k, x2= f1
+ // if f1 < math.Sqrt2/2 { k -= 1; f1 *= 2 }
+ MOVSD $HSqrt2, X0 // x0= 0.7071, x1= k, x2= f1
+ CMPSD X2, X0, 5 // cmpnlt; x0= 0 or ^0, x1= k, x2 = f1
+ MOVSD $1.0, X3 // x0= 0 or ^0, x1= k, x2 = f1, x3= 1
+ ANDPD X0, X3 // x0= 0 or ^0, x1= k, x2 = f1, x3= 0 or 1
+ SUBSD X3, X1 // x0= 0 or ^0, x1= k, x2 = f1, x3= 0 or 1
+ MOVSD $1.0, X0 // x0= 1, x1= k, x2= f1, x3= 0 or 1
+ ADDSD X0, X3 // x0= 1, x1= k, x2= f1, x3= 1 or 2
+ MULSD X3, X2 // x0= 1, x1= k, x2= f1
+ // f := f1 - 1
+ SUBSD X0, X2 // x1= k, x2= f
+ // s := f / (2 + f)
+ MOVSD $2.0, X0
+ ADDSD X2, X0
+ MOVAPD X2, X3
+ DIVSD X0, X3 // x1=k, x2= f, x3= s
+ // s2 := s * s
+ MOVAPD X3, X4 // x1= k, x2= f, x3= s
+ MULSD X4, X4 // x1= k, x2= f, x3= s, x4= s2
+ // s4 := s2 * s2
+ MOVAPD X4, X5 // x1= k, x2= f, x3= s, x4= s2
+ MULSD X5, X5 // x1= k, x2= f, x3= s, x4= s2, x5= s4
+ // t1 := s2 * (L1 + s4*(L3+s4*(L5+s4*L7)))
+ MOVSD $L7, X6
+ MULSD X5, X6
+ ADDSD $L5, X6
+ MULSD X5, X6
+ ADDSD $L3, X6
+ MULSD X5, X6
+ ADDSD $L1, X6
+ MULSD X6, X4 // x1= k, x2= f, x3= s, x4= t1, x5= s4
+ // t2 := s4 * (L2 + s4*(L4+s4*L6))
+ MOVSD $L6, X6
+ MULSD X5, X6
+ ADDSD $L4, X6
+ MULSD X5, X6
+ ADDSD $L2, X6
+ MULSD X6, X5 // x1= k, x2= f, x3= s, x4= t1, x5= t2
+ // R := t1 + t2
+ ADDSD X5, X4 // x1= k, x2= f, x3= s, x4= R
+ // hfsq := 0.5 * f * f
+ MOVSD $0.5, X0
+ MULSD X2, X0
+ MULSD X2, X0 // x0= hfsq, x1= k, x2= f, x3= s, x4= R
+ // return k*Ln2Hi - ((hfsq - (s*(hfsq+R) + k*Ln2Lo)) - f)
+ ADDSD X0, X4 // x0= hfsq, x1= k, x2= f, x3= s, x4= hfsq+R
+ MULSD X4, X3 // x0= hfsq, x1= k, x2= f, x3= s*(hfsq+R)
+ MOVSD $Ln2Lo, X4
+ MULSD X1, X4 // x4= k*Ln2Lo
+ ADDSD X4, X3 // x0= hfsq, x1= k, x2= f, x3= s*(hfsq+R)+k*Ln2Lo
+ SUBSD X3, X0 // x0= hfsq-(s*(hfsq+R)+k*Ln2Lo), x1= k, x2= f
+ SUBSD X2, X0 // x0= (hfsq-(s*(hfsq+R)+k*Ln2Lo))-f, x1= k
+ MULSD $Ln2Hi, X1 // x0= (hfsq-(s*(hfsq+R)+k*Ln2Lo))-f, x1= k*Ln2Hi
+ SUBSD X0, X1 // x1= k*Ln2Hi-((hfsq-(s*(hfsq+R)+k*Ln2Lo))-f)
+ MOVSD X1, ret+8(FP)
+ RET
+isInfOrNaN:
+ MOVQ BX, ret+8(FP) // +Inf or NaN, return x
+ RET
+isNegative:
+ MOVQ $NaN, AX
+ MOVQ AX, ret+8(FP) // return NaN
+ RET
+isZero:
+ MOVQ $NegInf, AX
+ MOVQ AX, ret+8(FP) // return -Inf
+ RET
diff --git a/go/src/math/log_asm.go b/go/src/math/log_asm.go
new file mode 100644
index 0000000000000000000000000000000000000000..848cce13b289b52e37c8f08e9c3d6d0c149831d7
--- /dev/null
+++ b/go/src/math/log_asm.go
@@ -0,0 +1,11 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build amd64 || s390x
+
+package math
+
+const haveArchLog = true
+
+func archLog(x float64) float64
diff --git a/go/src/math/log_s390x.s b/go/src/math/log_s390x.s
new file mode 100644
index 0000000000000000000000000000000000000000..215d7a03a7509f8a2739431f2d6fb1e0832fe428
--- /dev/null
+++ b/go/src/math/log_s390x.s
@@ -0,0 +1,168 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// Minimax polynomial approximations
+DATA ·logrodataL21<> + 0(SB)/8, $-.499999999999999778E+00
+DATA ·logrodataL21<> + 8(SB)/8, $0.333333333333343751E+00
+DATA ·logrodataL21<> + 16(SB)/8, $-.250000000001606881E+00
+DATA ·logrodataL21<> + 24(SB)/8, $0.199999999971603032E+00
+DATA ·logrodataL21<> + 32(SB)/8, $-.166666663114122038E+00
+DATA ·logrodataL21<> + 40(SB)/8, $-.125002923782692399E+00
+DATA ·logrodataL21<> + 48(SB)/8, $0.111142014580396256E+00
+DATA ·logrodataL21<> + 56(SB)/8, $0.759438932618934220E-01
+DATA ·logrodataL21<> + 64(SB)/8, $0.142857144267212549E+00
+DATA ·logrodataL21<> + 72(SB)/8, $-.993038938793590759E-01
+DATA ·logrodataL21<> + 80(SB)/8, $-1.0
+GLOBL ·logrodataL21<> + 0(SB), RODATA, $88
+
+// Constants
+DATA ·logxminf<> + 0(SB)/8, $0xfff0000000000000
+GLOBL ·logxminf<> + 0(SB), RODATA, $8
+DATA ·logxnan<> + 0(SB)/8, $0x7ff8000000000000
+GLOBL ·logxnan<> + 0(SB), RODATA, $8
+DATA ·logx43f<> + 0(SB)/8, $0x43f0000000000000
+GLOBL ·logx43f<> + 0(SB), RODATA, $8
+DATA ·logxl2<> + 0(SB)/8, $0x3fda7aecbeba4e46
+GLOBL ·logxl2<> + 0(SB), RODATA, $8
+DATA ·logxl1<> + 0(SB)/8, $0x3ffacde700000000
+GLOBL ·logxl1<> + 0(SB), RODATA, $8
+
+/* Input transform scale and add constants */
+DATA ·logxm<> + 0(SB)/8, $0x3fc77604e63c84b1
+DATA ·logxm<> + 8(SB)/8, $0x40fb39456ab53250
+DATA ·logxm<> + 16(SB)/8, $0x3fc9ee358b945f3f
+DATA ·logxm<> + 24(SB)/8, $0x40fb39418bf3b137
+DATA ·logxm<> + 32(SB)/8, $0x3fccfb2e1304f4b6
+DATA ·logxm<> + 40(SB)/8, $0x40fb393d3eda3022
+DATA ·logxm<> + 48(SB)/8, $0x3fd0000000000000
+DATA ·logxm<> + 56(SB)/8, $0x40fb393969e70000
+DATA ·logxm<> + 64(SB)/8, $0x3fd11117aafbfe04
+DATA ·logxm<> + 72(SB)/8, $0x40fb3936eaefafcf
+DATA ·logxm<> + 80(SB)/8, $0x3fd2492af5e658b2
+DATA ·logxm<> + 88(SB)/8, $0x40fb39343ff01715
+DATA ·logxm<> + 96(SB)/8, $0x3fd3b50c622a43dd
+DATA ·logxm<> + 104(SB)/8, $0x40fb39315adae2f3
+DATA ·logxm<> + 112(SB)/8, $0x3fd56bbeea918777
+DATA ·logxm<> + 120(SB)/8, $0x40fb392e21698552
+GLOBL ·logxm<> + 0(SB), RODATA, $128
+
+// Log returns the natural logarithm of the argument.
+//
+// Special cases are:
+// Log(+Inf) = +Inf
+// Log(0) = -Inf
+// Log(x < 0) = NaN
+// Log(NaN) = NaN
+// The algorithm used is minimax polynomial approximation using a table of
+// polynomial coefficients determined with a Remez exchange algorithm.
+
+TEXT ·logAsm(SB), NOSPLIT, $0-16
+ FMOVD x+0(FP), F0
+ MOVD $·logrodataL21<>+0(SB), R9
+ MOVH $0x8006, R4
+ LGDR F0, R1
+ MOVD $0x3FF0000000000000, R6
+ SRAD $48, R1, R1
+ MOVD $0x40F03E8000000000, R8
+ SUBW R1, R4
+ RISBGZ $32, $59, $0, R4, R2
+ RISBGN $0, $15, $48, R2, R6
+ RISBGN $16, $31, $32, R2, R8
+ MOVW R1, R7
+ CMPBGT R7, $22, L17
+ LTDBR F0, F0
+ MOVD $·logx43f<>+0(SB), R1
+ FMOVD 0(R1), F2
+ BLEU L3
+ MOVH $0x8005, R12
+ MOVH $0x8405, R0
+ BR L15
+L7:
+ LTDBR F0, F0
+ BLEU L3
+L15:
+ FMUL F2, F0
+ LGDR F0, R1
+ SRAD $48, R1, R1
+ SUBW R1, R0, R2
+ SUBW R1, R12, R3
+ BYTE $0x18 //lr %r4,%r2
+ BYTE $0x42
+ ANDW $0xFFFFFFF0, R3
+ ANDW $0xFFFFFFF0, R2
+ BYTE $0x18 //lr %r5,%r1
+ BYTE $0x51
+ MOVW R1, R7
+ CMPBLE R7, $22, L7
+ RISBGN $0, $15, $48, R3, R6
+ RISBGN $16, $31, $32, R2, R8
+L2:
+ MOVH R5, R5
+ MOVH $0x7FEF, R1
+ CMPW R5, R1
+ BGT L1
+ LDGR R6, F2
+ FMUL F2, F0
+ RISBGZ $57, $59, $3, R4, R4
+ FMOVD 80(R9), F2
+ MOVD $·logxm<>+0(SB), R7
+ ADD R7, R4
+ FMOVD 72(R9), F4
+ WORD $0xED004000 //madb %f2,%f0,0(%r4)
+ BYTE $0x20
+ BYTE $0x1E
+ FMOVD 64(R9), F1
+ FMOVD F2, F0
+ FMOVD 56(R9), F2
+ WFMADB V0, V2, V4, V2
+ WFMDB V0, V0, V6
+ FMOVD 48(R9), F4
+ WFMADB V0, V2, V4, V2
+ FMOVD 40(R9), F4
+ WFMADB V2, V6, V1, V2
+ FMOVD 32(R9), F1
+ WFMADB V6, V4, V1, V4
+ FMOVD 24(R9), F1
+ WFMADB V6, V2, V1, V2
+ FMOVD 16(R9), F1
+ WFMADB V6, V4, V1, V4
+ MOVD $·logxl1<>+0(SB), R1
+ FMOVD 8(R9), F1
+ WFMADB V6, V2, V1, V2
+ FMOVD 0(R9), F1
+ WFMADB V6, V4, V1, V4
+ FMOVD 8(R4), F1
+ WFMADB V0, V2, V4, V2
+ LDGR R8, F4
+ WFMADB V6, V2, V0, V2
+ WORD $0xED401000 //msdb %f1,%f4,0(%r1)
+ BYTE $0x10
+ BYTE $0x1F
+ MOVD ·logxl2<>+0(SB), R1
+ LCDBR F1, F0
+ LDGR R1, F4
+ WFMADB V0, V4, V2, V0
+L1:
+ FMOVD F0, ret+8(FP)
+ RET
+L3:
+ LTDBR F0, F0
+ BEQ L20
+ BGE L1
+ BVS L1
+
+ MOVD $·logxnan<>+0(SB), R1
+ FMOVD 0(R1), F0
+ BR L1
+L20:
+ MOVD $·logxminf<>+0(SB), R1
+ FMOVD 0(R1), F0
+ FMOVD F0, ret+8(FP)
+ RET
+L17:
+ BYTE $0x18 //lr %r5,%r1
+ BYTE $0x51
+ BR L2
diff --git a/go/src/math/log_stub.go b/go/src/math/log_stub.go
new file mode 100644
index 0000000000000000000000000000000000000000..d35992bf37ab69227a4afe49a21cef7e37d0fc30
--- /dev/null
+++ b/go/src/math/log_stub.go
@@ -0,0 +1,13 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !amd64 && !s390x
+
+package math
+
+const haveArchLog = false
+
+func archLog(x float64) float64 {
+ panic("not implemented")
+}
diff --git a/go/src/math/logb.go b/go/src/math/logb.go
new file mode 100644
index 0000000000000000000000000000000000000000..1a46464127cc886aa78ad825c075fda4eab05614
--- /dev/null
+++ b/go/src/math/logb.go
@@ -0,0 +1,52 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Logb returns the binary exponent of x.
+//
+// Special cases are:
+//
+// Logb(±Inf) = +Inf
+// Logb(0) = -Inf
+// Logb(NaN) = NaN
+func Logb(x float64) float64 {
+ // special cases
+ switch {
+ case x == 0:
+ return Inf(-1)
+ case IsInf(x, 0):
+ return Inf(1)
+ case IsNaN(x):
+ return x
+ }
+ return float64(ilogb(x))
+}
+
+// Ilogb returns the binary exponent of x as an integer.
+//
+// Special cases are:
+//
+// Ilogb(±Inf) = MaxInt32
+// Ilogb(0) = MinInt32
+// Ilogb(NaN) = MaxInt32
+func Ilogb(x float64) int {
+ // special cases
+ switch {
+ case x == 0:
+ return MinInt32
+ case IsNaN(x):
+ return MaxInt32
+ case IsInf(x, 0):
+ return MaxInt32
+ }
+ return ilogb(x)
+}
+
+// ilogb returns the binary exponent of x. It assumes x is finite and
+// non-zero.
+func ilogb(x float64) int {
+ x, exp := normalize(x)
+ return int((Float64bits(x)>>shift)&mask) - bias + exp
+}
diff --git a/go/src/math/mod.go b/go/src/math/mod.go
new file mode 100644
index 0000000000000000000000000000000000000000..6f24250cfb461265fa51362c7ccc140c559abfc7
--- /dev/null
+++ b/go/src/math/mod.go
@@ -0,0 +1,52 @@
+// Copyright 2009-2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+ Floating-point mod function.
+*/
+
+// Mod returns the floating-point remainder of x/y.
+// The magnitude of the result is less than y and its
+// sign agrees with that of x.
+//
+// Special cases are:
+//
+// Mod(±Inf, y) = NaN
+// Mod(NaN, y) = NaN
+// Mod(x, 0) = NaN
+// Mod(x, ±Inf) = x
+// Mod(x, NaN) = NaN
+func Mod(x, y float64) float64 {
+ if haveArchMod {
+ return archMod(x, y)
+ }
+ return mod(x, y)
+}
+
+func mod(x, y float64) float64 {
+ if y == 0 || IsInf(x, 0) || IsNaN(x) || IsNaN(y) {
+ return NaN()
+ }
+ y = Abs(y)
+
+ yfr, yexp := Frexp(y)
+ r := x
+ if x < 0 {
+ r = -x
+ }
+
+ for r >= y {
+ rfr, rexp := Frexp(r)
+ if rfr < yfr {
+ rexp = rexp - 1
+ }
+ r = r - Ldexp(y, rexp-yexp)
+ }
+ if x < 0 {
+ r = -r
+ }
+ return r
+}
diff --git a/go/src/math/modf.go b/go/src/math/modf.go
new file mode 100644
index 0000000000000000000000000000000000000000..12630958e969b7a820016d4b005216ebcb515486
--- /dev/null
+++ b/go/src/math/modf.go
@@ -0,0 +1,18 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Modf returns integer and fractional floating-point numbers
+// that sum to f. Both values have the same sign as f.
+//
+// Special cases are:
+//
+// Modf(±Inf) = ±Inf, NaN
+// Modf(NaN) = NaN, NaN
+func Modf(f float64) (integer float64, fractional float64) {
+ integer = Trunc(f)
+ fractional = Copysign(f-integer, f)
+ return
+}
diff --git a/go/src/math/nextafter.go b/go/src/math/nextafter.go
new file mode 100644
index 0000000000000000000000000000000000000000..ec18d542d9c0371d0b69831971faa415ab0f216c
--- /dev/null
+++ b/go/src/math/nextafter.go
@@ -0,0 +1,51 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Nextafter32 returns the next representable float32 value after x towards y.
+//
+// Special cases are:
+//
+// Nextafter32(x, x) = x
+// Nextafter32(NaN, y) = NaN
+// Nextafter32(x, NaN) = NaN
+func Nextafter32(x, y float32) (r float32) {
+ switch {
+ case IsNaN(float64(x)) || IsNaN(float64(y)): // special case
+ r = float32(NaN())
+ case x == y:
+ r = x
+ case x == 0:
+ r = float32(Copysign(float64(Float32frombits(1)), float64(y)))
+ case (y > x) == (x > 0):
+ r = Float32frombits(Float32bits(x) + 1)
+ default:
+ r = Float32frombits(Float32bits(x) - 1)
+ }
+ return
+}
+
+// Nextafter returns the next representable float64 value after x towards y.
+//
+// Special cases are:
+//
+// Nextafter(x, x) = x
+// Nextafter(NaN, y) = NaN
+// Nextafter(x, NaN) = NaN
+func Nextafter(x, y float64) (r float64) {
+ switch {
+ case IsNaN(x) || IsNaN(y): // special case
+ r = NaN()
+ case x == y:
+ r = x
+ case x == 0:
+ r = Copysign(Float64frombits(1), y)
+ case (y > x) == (x > 0):
+ r = Float64frombits(Float64bits(x) + 1)
+ default:
+ r = Float64frombits(Float64bits(x) - 1)
+ }
+ return
+}
diff --git a/go/src/math/pow.go b/go/src/math/pow.go
new file mode 100644
index 0000000000000000000000000000000000000000..3f42945376d3fac2888d27cfe848ffecdf3abfdc
--- /dev/null
+++ b/go/src/math/pow.go
@@ -0,0 +1,166 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+func isOddInt(x float64) bool {
+ if Abs(x) >= (1 << 53) {
+ // 1 << 53 is the largest exact integer in the float64 format.
+ // Any number outside this range will be truncated before the decimal point and therefore will always be
+ // an even integer.
+ // Without this check and if x overflows int64 the int64(xi) conversion below may produce incorrect results
+ // on some architectures (and does so on arm64). See issue #57465.
+ return false
+ }
+
+ xi, xf := Modf(x)
+ return xf == 0 && int64(xi)&1 == 1
+}
+
+// Special cases taken from FreeBSD's /usr/src/lib/msun/src/e_pow.c
+// updated by IEEE Std. 754-2008 "Section 9.2.1 Special values".
+
+// Pow returns x**y, the base-x exponential of y.
+//
+// Special cases are (in order):
+//
+// Pow(x, ±0) = 1 for any x
+// Pow(1, y) = 1 for any y
+// Pow(x, 1) = x for any x
+// Pow(NaN, y) = NaN
+// Pow(x, NaN) = NaN
+// Pow(±0, y) = ±Inf for y an odd integer < 0
+// Pow(±0, -Inf) = +Inf
+// Pow(±0, +Inf) = +0
+// Pow(±0, y) = +Inf for finite y < 0 and not an odd integer
+// Pow(±0, y) = ±0 for y an odd integer > 0
+// Pow(±0, y) = +0 for finite y > 0 and not an odd integer
+// Pow(-1, ±Inf) = 1
+// Pow(x, +Inf) = +Inf for |x| > 1
+// Pow(x, -Inf) = +0 for |x| > 1
+// Pow(x, +Inf) = +0 for |x| < 1
+// Pow(x, -Inf) = +Inf for |x| < 1
+// Pow(+Inf, y) = +Inf for y > 0
+// Pow(+Inf, y) = +0 for y < 0
+// Pow(-Inf, y) = Pow(-0, -y)
+// Pow(x, y) = NaN for finite x < 0 and finite non-integer y
+func Pow(x, y float64) float64 {
+ if haveArchPow {
+ return archPow(x, y)
+ }
+ return pow(x, y)
+}
+
+func pow(x, y float64) float64 {
+ switch {
+ case y == 0 || x == 1:
+ return 1
+ case y == 1:
+ return x
+ case IsNaN(x) || IsNaN(y):
+ return NaN()
+ case x == 0:
+ switch {
+ case y < 0:
+ if Signbit(x) && isOddInt(y) {
+ return Inf(-1)
+ }
+ return Inf(1)
+ case y > 0:
+ if Signbit(x) && isOddInt(y) {
+ return x
+ }
+ return 0
+ }
+ case IsInf(y, 0):
+ switch {
+ case x == -1:
+ return 1
+ case (Abs(x) < 1) == IsInf(y, 1):
+ return 0
+ default:
+ return Inf(1)
+ }
+ case IsInf(x, 0):
+ if IsInf(x, -1) {
+ return Pow(1/x, -y) // Pow(-0, -y)
+ }
+ switch {
+ case y < 0:
+ return 0
+ case y > 0:
+ return Inf(1)
+ }
+ case y == 0.5:
+ return Sqrt(x)
+ case y == -0.5:
+ return 1 / Sqrt(x)
+ }
+
+ yi, yf := Modf(Abs(y))
+ if yf != 0 && x < 0 {
+ return NaN()
+ }
+ if yi >= 1<<63 {
+ // yi is a large even int that will lead to overflow (or underflow to 0)
+ // for all x except -1 (x == 1 was handled earlier)
+ switch {
+ case x == -1:
+ return 1
+ case (Abs(x) < 1) == (y > 0):
+ return 0
+ default:
+ return Inf(1)
+ }
+ }
+
+ // ans = a1 * 2**ae (= 1 for now).
+ a1 := 1.0
+ ae := 0
+
+ // ans *= x**yf
+ if yf != 0 {
+ if yf > 0.5 {
+ yf--
+ yi++
+ }
+ a1 = Exp(yf * Log(x))
+ }
+
+ // ans *= x**yi
+ // by multiplying in successive squarings
+ // of x according to bits of yi.
+ // accumulate powers of two into exp.
+ x1, xe := Frexp(x)
+ for i := int64(yi); i != 0; i >>= 1 {
+ if xe < -1<<12 || 1<<12 < xe {
+ // catch xe before it overflows the left shift below
+ // Since i !=0 it has at least one bit still set, so ae will accumulate xe
+ // on at least one more iteration, ae += xe is a lower bound on ae
+ // the lower bound on ae exceeds the size of a float64 exp
+ // so the final call to Ldexp will produce under/overflow (0/Inf)
+ ae += xe
+ break
+ }
+ if i&1 == 1 {
+ a1 *= x1
+ ae += xe
+ }
+ x1 *= x1
+ xe <<= 1
+ if x1 < .5 {
+ x1 += x1
+ xe--
+ }
+ }
+
+ // ans = a1*2**ae
+ // if y < 0 { ans = 1 / ans }
+ // but in the opposite order
+ if y < 0 {
+ a1 = 1 / a1
+ ae = -ae
+ }
+ return Ldexp(a1, ae)
+}
diff --git a/go/src/math/pow10.go b/go/src/math/pow10.go
new file mode 100644
index 0000000000000000000000000000000000000000..c31ad8dbc778fe5dbd2a676645019b7ac0e91974
--- /dev/null
+++ b/go/src/math/pow10.go
@@ -0,0 +1,47 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// pow10tab stores the pre-computed values 10**i for i < 32.
+var pow10tab = [...]float64{
+ 1e00, 1e01, 1e02, 1e03, 1e04, 1e05, 1e06, 1e07, 1e08, 1e09,
+ 1e10, 1e11, 1e12, 1e13, 1e14, 1e15, 1e16, 1e17, 1e18, 1e19,
+ 1e20, 1e21, 1e22, 1e23, 1e24, 1e25, 1e26, 1e27, 1e28, 1e29,
+ 1e30, 1e31,
+}
+
+// pow10postab32 stores the pre-computed value for 10**(i*32) at index i.
+var pow10postab32 = [...]float64{
+ 1e00, 1e32, 1e64, 1e96, 1e128, 1e160, 1e192, 1e224, 1e256, 1e288,
+}
+
+// pow10negtab32 stores the pre-computed value for 10**(-i*32) at index i.
+var pow10negtab32 = [...]float64{
+ 1e-00, 1e-32, 1e-64, 1e-96, 1e-128, 1e-160, 1e-192, 1e-224, 1e-256, 1e-288, 1e-320,
+}
+
+// Pow10 returns 10**n, the base-10 exponential of n.
+//
+// Special cases are:
+//
+// Pow10(n) = 0 for n < -323
+// Pow10(n) = +Inf for n > 308
+func Pow10(n int) float64 {
+ if 0 <= n && n <= 308 {
+ return pow10postab32[uint(n)/32] * pow10tab[uint(n)%32]
+ }
+
+ if -323 <= n && n <= 0 {
+ return pow10negtab32[uint(-n)/32] / pow10tab[uint(-n)%32]
+ }
+
+ // n < -323 || 308 < n
+ if n > 0 {
+ return Inf(1)
+ }
+
+ // n < -323
+ return 0
+}
diff --git a/go/src/math/pow_s390x.s b/go/src/math/pow_s390x.s
new file mode 100644
index 0000000000000000000000000000000000000000..97cd48d96ec85008138c877c0ebadc0172690f53
--- /dev/null
+++ b/go/src/math/pow_s390x.s
@@ -0,0 +1,634 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+#define PosInf 0x7FF0000000000000
+#define NaN 0x7FF8000000000001
+#define NegInf 0xFFF0000000000000
+#define PosOne 0x3FF0000000000000
+#define NegOne 0xBFF0000000000000
+#define NegZero 0x8000000000000000
+
+// Minimax polynomial approximation
+DATA ·powrodataL51<> + 0(SB)/8, $-1.0
+DATA ·powrodataL51<> + 8(SB)/8, $1.0
+DATA ·powrodataL51<> + 16(SB)/8, $0.24022650695910110361E+00
+DATA ·powrodataL51<> + 24(SB)/8, $0.69314718055994686185E+00
+DATA ·powrodataL51<> + 32(SB)/8, $0.96181291057109484809E-02
+DATA ·powrodataL51<> + 40(SB)/8, $0.15403814778342868389E-03
+DATA ·powrodataL51<> + 48(SB)/8, $0.55504108652095235601E-01
+DATA ·powrodataL51<> + 56(SB)/8, $0.13333818813168698658E-02
+DATA ·powrodataL51<> + 64(SB)/8, $0.68205322933914439200E-12
+DATA ·powrodataL51<> + 72(SB)/8, $-.18466496523378731640E-01
+DATA ·powrodataL51<> + 80(SB)/8, $0.19697596291603973706E-02
+DATA ·powrodataL51<> + 88(SB)/8, $0.23083120654155209200E+00
+DATA ·powrodataL51<> + 96(SB)/8, $0.55324356012093416771E-06
+DATA ·powrodataL51<> + 104(SB)/8, $-.40340677224649339048E-05
+DATA ·powrodataL51<> + 112(SB)/8, $0.30255507904062541562E-04
+DATA ·powrodataL51<> + 120(SB)/8, $-.77453979912413008787E-07
+DATA ·powrodataL51<> + 128(SB)/8, $-.23637115549923464737E-03
+DATA ·powrodataL51<> + 136(SB)/8, $0.11016119077267717198E-07
+DATA ·powrodataL51<> + 144(SB)/8, $0.22608272174486123035E-09
+DATA ·powrodataL51<> + 152(SB)/8, $-.15895808101370190382E-08
+DATA ·powrodataL51<> + 160(SB)/8, $0x4540190000000000
+GLOBL ·powrodataL51<> + 0(SB), RODATA, $168
+
+// Constants
+DATA ·pow_x001a<> + 0(SB)/8, $0x1a000000000000
+GLOBL ·pow_x001a<> + 0(SB), RODATA, $8
+DATA ·pow_xinf<> + 0(SB)/8, $0x7ff0000000000000 //+Inf
+GLOBL ·pow_xinf<> + 0(SB), RODATA, $8
+DATA ·pow_xnan<> + 0(SB)/8, $0x7ff8000000000000 //NaN
+GLOBL ·pow_xnan<> + 0(SB), RODATA, $8
+DATA ·pow_x434<> + 0(SB)/8, $0x4340000000000000
+GLOBL ·pow_x434<> + 0(SB), RODATA, $8
+DATA ·pow_x433<> + 0(SB)/8, $0x4330000000000000
+GLOBL ·pow_x433<> + 0(SB), RODATA, $8
+DATA ·pow_x43f<> + 0(SB)/8, $0x43f0000000000000
+GLOBL ·pow_x43f<> + 0(SB), RODATA, $8
+DATA ·pow_xadd<> + 0(SB)/8, $0xc2f0000100003fef
+GLOBL ·pow_xadd<> + 0(SB), RODATA, $8
+DATA ·pow_xa<> + 0(SB)/8, $0x4019000000000000
+GLOBL ·pow_xa<> + 0(SB), RODATA, $8
+
+// Scale correction tables
+DATA powiadd<> + 0(SB)/8, $0xf000000000000000
+DATA powiadd<> + 8(SB)/8, $0x1000000000000000
+GLOBL powiadd<> + 0(SB), RODATA, $16
+DATA powxscale<> + 0(SB)/8, $0x4ff0000000000000
+DATA powxscale<> + 8(SB)/8, $0x2ff0000000000000
+GLOBL powxscale<> + 0(SB), RODATA, $16
+
+// Fractional powers of 2 table
+DATA ·powtexp<> + 0(SB)/8, $0.442737824274138381E-01
+DATA ·powtexp<> + 8(SB)/8, $0.263602189790660309E-01
+DATA ·powtexp<> + 16(SB)/8, $0.122565642281703586E-01
+DATA ·powtexp<> + 24(SB)/8, $0.143757052860721398E-02
+DATA ·powtexp<> + 32(SB)/8, $-.651375034121276075E-02
+DATA ·powtexp<> + 40(SB)/8, $-.119317678849450159E-01
+DATA ·powtexp<> + 48(SB)/8, $-.150868749549871069E-01
+DATA ·powtexp<> + 56(SB)/8, $-.161992609578469234E-01
+DATA ·powtexp<> + 64(SB)/8, $-.154492360403337917E-01
+DATA ·powtexp<> + 72(SB)/8, $-.129850717389178721E-01
+DATA ·powtexp<> + 80(SB)/8, $-.892902649276657891E-02
+DATA ·powtexp<> + 88(SB)/8, $-.338202636596794887E-02
+DATA ·powtexp<> + 96(SB)/8, $0.357266307045684762E-02
+DATA ·powtexp<> + 104(SB)/8, $0.118665304327406698E-01
+DATA ·powtexp<> + 112(SB)/8, $0.214434994118118914E-01
+DATA ·powtexp<> + 120(SB)/8, $0.322580645161290314E-01
+GLOBL ·powtexp<> + 0(SB), RODATA, $128
+
+// Log multiplier tables
+DATA ·powtl<> + 0(SB)/8, $0xbdf9723a80db6a05
+DATA ·powtl<> + 8(SB)/8, $0x3e0cfe4a0babe862
+DATA ·powtl<> + 16(SB)/8, $0xbe163b42dd33dada
+DATA ·powtl<> + 24(SB)/8, $0xbe0cdf9de2a8429c
+DATA ·powtl<> + 32(SB)/8, $0xbde9723a80db6a05
+DATA ·powtl<> + 40(SB)/8, $0xbdb37fcae081745e
+DATA ·powtl<> + 48(SB)/8, $0xbdd8b2f901ac662c
+DATA ·powtl<> + 56(SB)/8, $0xbde867dc68c36cc9
+DATA ·powtl<> + 64(SB)/8, $0xbdd23e36b47256b7
+DATA ·powtl<> + 72(SB)/8, $0xbde4c9b89fcc7933
+DATA ·powtl<> + 80(SB)/8, $0xbdd16905cad7cf66
+DATA ·powtl<> + 88(SB)/8, $0x3ddb417414aa5529
+DATA ·powtl<> + 96(SB)/8, $0xbdce046f2889983c
+DATA ·powtl<> + 104(SB)/8, $0x3dc2c3865d072897
+DATA ·powtl<> + 112(SB)/8, $0x8000000000000000
+DATA ·powtl<> + 120(SB)/8, $0x3dc1ca48817f8afe
+DATA ·powtl<> + 128(SB)/8, $0xbdd703518a88bfb7
+DATA ·powtl<> + 136(SB)/8, $0x3dc64afcc46942ce
+DATA ·powtl<> + 144(SB)/8, $0xbd9d79191389891a
+DATA ·powtl<> + 152(SB)/8, $0x3ddd563044da4fa0
+DATA ·powtl<> + 160(SB)/8, $0x3e0f42b5e5f8f4b6
+DATA ·powtl<> + 168(SB)/8, $0x3e0dfa2c2cbf6ead
+DATA ·powtl<> + 176(SB)/8, $0x3e14e25e91661293
+DATA ·powtl<> + 184(SB)/8, $0x3e0aac461509e20c
+GLOBL ·powtl<> + 0(SB), RODATA, $192
+
+DATA ·powtm<> + 0(SB)/8, $0x3da69e13
+DATA ·powtm<> + 8(SB)/8, $0x100003d66fcb6
+DATA ·powtm<> + 16(SB)/8, $0x200003d1538df
+DATA ·powtm<> + 24(SB)/8, $0x300003cab729e
+DATA ·powtm<> + 32(SB)/8, $0x400003c1a784c
+DATA ·powtm<> + 40(SB)/8, $0x500003ac9b074
+DATA ·powtm<> + 48(SB)/8, $0x60000bb498d22
+DATA ·powtm<> + 56(SB)/8, $0x68000bb8b29a2
+DATA ·powtm<> + 64(SB)/8, $0x70000bb9a32d4
+DATA ·powtm<> + 72(SB)/8, $0x74000bb9946bb
+DATA ·powtm<> + 80(SB)/8, $0x78000bb92e34b
+DATA ·powtm<> + 88(SB)/8, $0x80000bb6c57dc
+DATA ·powtm<> + 96(SB)/8, $0x84000bb4020f7
+DATA ·powtm<> + 104(SB)/8, $0x8c000ba93832d
+DATA ·powtm<> + 112(SB)/8, $0x9000080000000
+DATA ·powtm<> + 120(SB)/8, $0x940003aa66c4c
+DATA ·powtm<> + 128(SB)/8, $0x980003b2fb12a
+DATA ·powtm<> + 136(SB)/8, $0xa00003bc1def6
+DATA ·powtm<> + 144(SB)/8, $0xa80003c1eb0eb
+DATA ·powtm<> + 152(SB)/8, $0xb00003c64dcec
+DATA ·powtm<> + 160(SB)/8, $0xc00003cc49e4e
+DATA ·powtm<> + 168(SB)/8, $0xd00003d12f1de
+DATA ·powtm<> + 176(SB)/8, $0xe00003d4a9c6f
+DATA ·powtm<> + 184(SB)/8, $0xf00003d846c66
+GLOBL ·powtm<> + 0(SB), RODATA, $192
+
+// Table of indices into multiplier tables
+// Adjusted from asm to remove offset and convert
+DATA ·powtabi<> + 0(SB)/8, $0x1010101
+DATA ·powtabi<> + 8(SB)/8, $0x101020202020203
+DATA ·powtabi<> + 16(SB)/8, $0x303030404040405
+DATA ·powtabi<> + 24(SB)/8, $0x505050606060708
+DATA ·powtabi<> + 32(SB)/8, $0x90a0b0c0d0e0f10
+DATA ·powtabi<> + 40(SB)/8, $0x1011111212121313
+DATA ·powtabi<> + 48(SB)/8, $0x1314141414151515
+DATA ·powtabi<> + 56(SB)/8, $0x1516161617171717
+GLOBL ·powtabi<> + 0(SB), RODATA, $64
+
+// Pow returns x**y, the base-x exponential of y.
+//
+// Special cases are (in order):
+// Pow(x, ±0) = 1 for any x
+// Pow(1, y) = 1 for any y
+// Pow(x, 1) = x for any x
+// Pow(NaN, y) = NaN
+// Pow(x, NaN) = NaN
+// Pow(±0, y) = ±Inf for y an odd integer < 0
+// Pow(±0, -Inf) = +Inf
+// Pow(±0, +Inf) = +0
+// Pow(±0, y) = +Inf for finite y < 0 and not an odd integer
+// Pow(±0, y) = ±0 for y an odd integer > 0
+// Pow(±0, y) = +0 for finite y > 0 and not an odd integer
+// Pow(-1, ±Inf) = 1
+// Pow(x, +Inf) = +Inf for |x| > 1
+// Pow(x, -Inf) = +0 for |x| > 1
+// Pow(x, +Inf) = +0 for |x| < 1
+// Pow(x, -Inf) = +Inf for |x| < 1
+// Pow(+Inf, y) = +Inf for y > 0
+// Pow(+Inf, y) = +0 for y < 0
+// Pow(-Inf, y) = Pow(-0, -y)
+// Pow(x, y) = NaN for finite x < 0 and finite non-integer y
+
+TEXT ·powAsm(SB), NOSPLIT, $0-24
+ // special case
+ MOVD x+0(FP), R1
+ MOVD y+8(FP), R2
+
+ // special case Pow(1, y) = 1 for any y
+ MOVD $PosOne, R3
+ CMPUBEQ R1, R3, xIsOne
+
+ // special case Pow(x, 1) = x for any x
+ MOVD $PosOne, R4
+ CMPUBEQ R2, R4, yIsOne
+
+ // special case Pow(x, NaN) = NaN for any x
+ MOVD $~(1<<63), R5
+ AND R2, R5 // y = |y|
+ MOVD $PosInf, R4
+ CMPUBLT R4, R5, yIsNan
+
+ MOVD $NegInf, R3
+ CMPUBEQ R1, R3, xIsNegInf
+
+ MOVD $NegOne, R3
+ CMPUBEQ R1, R3, xIsNegOne
+
+ MOVD $PosInf, R3
+ CMPUBEQ R1, R3, xIsPosInf
+
+ MOVD $NegZero, R3
+ CMPUBEQ R1, R3, xIsNegZero
+
+ MOVD $PosInf, R4
+ CMPUBEQ R2, R4, yIsPosInf
+
+ MOVD $0x0, R3
+ CMPUBEQ R1, R3, xIsPosZero
+ CMPBLT R1, R3, xLtZero
+ BR Normal
+xIsPosInf:
+ // special case Pow(+Inf, y) = +Inf for y > 0
+ MOVD $0x0, R4
+ CMPBGT R2, R4, posInfGeZero
+ BR Normal
+xIsNegInf:
+ //Pow(-Inf, y) = Pow(-0, -y)
+ FMOVD y+8(FP), F2
+ FNEG F2, F2 // y = -y
+ BR negZeroNegY // call Pow(-0, -y)
+xIsNegOne:
+ // special case Pow(-1, ±Inf) = 1
+ MOVD $PosInf, R4
+ CMPUBEQ R2, R4, negOnePosInf
+ MOVD $NegInf, R4
+ CMPUBEQ R2, R4, negOneNegInf
+ BR Normal
+xIsPosZero:
+ // special case Pow(+0, -Inf) = +Inf
+ MOVD $NegInf, R4
+ CMPUBEQ R2, R4, zeroNegInf
+
+ // special case Pow(+0, y < 0) = +Inf
+ FMOVD y+8(FP), F2
+ FMOVD $(0.0), F4
+ FCMPU F2, F4
+ BLT posZeroLtZero //y < 0.0
+ BR Normal
+xIsNegZero:
+ // special case Pow(-0, -Inf) = +Inf
+ MOVD $NegInf, R4
+ CMPUBEQ R2, R4, zeroNegInf
+ FMOVD y+8(FP), F2
+negZeroNegY:
+ // special case Pow(x, ±0) = 1 for any x
+ FMOVD $(0.0), F4
+ FCMPU F4, F2
+ BLT negZeroGtZero // y > 0.0
+ BEQ yIsZero // y = 0.0
+
+ FMOVD $(-0.0), F4
+ FCMPU F4, F2
+ BLT negZeroGtZero // y > -0.0
+ BEQ yIsZero // y = -0.0
+
+ // special case Pow(-0, y) = -Inf for y an odd integer < 0
+ // special case Pow(-0, y) = +Inf for finite y < 0 and not an odd integer
+ FIDBR $5, F2, F4 //F2 translate to integer F4
+ FCMPU F2, F4
+ BNE zeroNotOdd // y is not an (odd) integer and y < 0
+ FMOVD $(2.0), F4
+ FDIV F4, F2 // F2 = F2 / 2.0
+ FIDBR $5, F2, F4 //F2 translate to integer F4
+ FCMPU F2, F4
+ BNE negZeroOddInt // y is an odd integer and y < 0
+ BR zeroNotOdd // y is not an (odd) integer and y < 0
+
+negZeroGtZero:
+ // special case Pow(-0, y) = -0 for y an odd integer > 0
+ // special case Pow(±0, y) = +0 for finite y > 0 and not an odd integer
+ FIDBR $5, F2, F4 //F2 translate to integer F4
+ FCMPU F2, F4
+ BNE zeroNotOddGtZero // y is not an (odd) integer and y > 0
+ FMOVD $(2.0), F4
+ FDIV F4, F2 // F2 = F2 / 2.0
+ FIDBR $5, F2, F4 //F2 translate to integer F4
+ FCMPU F2, F4
+ BNE negZeroOddIntGtZero // y is an odd integer and y > 0
+ BR zeroNotOddGtZero // y is not an (odd) integer
+
+xLtZero:
+ // special case Pow(x, y) = NaN for finite x < 0 and finite non-integer y
+ FMOVD y+8(FP), F2
+ FIDBR $5, F2, F4
+ FCMPU F2, F4
+ BNE ltZeroInt
+ BR Normal
+yIsPosInf:
+ // special case Pow(x, +Inf) = +Inf for |x| > 1
+ FMOVD x+0(FP), F1
+ FMOVD $(1.0), F3
+ FCMPU F1, F3
+ BGT gtOnePosInf
+ FMOVD $(-1.0), F3
+ FCMPU F1, F3
+ BLT ltNegOnePosInf
+Normal:
+ FMOVD x+0(FP), F0
+ FMOVD y+8(FP), F2
+ MOVD $·powrodataL51<>+0(SB), R9
+ LGDR F0, R3
+ WORD $0xC0298009 //iilf %r2,2148095317
+ BYTE $0x55
+ BYTE $0x55
+ RISBGNZ $32, $63, $32, R3, R1
+ SUBW R1, R2
+ RISBGNZ $58, $63, $50, R2, R3
+ BYTE $0x18 //lr %r5,%r1
+ BYTE $0x51
+ MOVD $·powtabi<>+0(SB), R12
+ WORD $0xE303C000 //llgc %r0,0(%r3,%r12)
+ BYTE $0x00
+ BYTE $0x90
+ SUBW $0x1A0000, R5
+ SLD $3, R0, R3
+ MOVD $·powtm<>+0(SB), R4
+ MOVH $0x0, R8
+ ANDW $0x7FF00000, R2
+ ORW R5, R1
+ WORD $0x5A234000 //a %r2,0(%r3,%r4)
+ MOVD $0x3FF0000000000000, R5
+ RISBGZ $40, $63, $56, R2, R3
+ RISBGN $0, $31, $32, R2, R8
+ ORW $0x45000000, R3
+ MOVW R1, R6
+ CMPBLT R6, $0, L42
+ FMOVD F0, F4
+L2:
+ VLVGF $0, R3, V1
+ MOVD $·pow_xa<>+0(SB), R2
+ WORD $0xED3090A0 //lde %f3,.L52-.L51(%r9)
+ BYTE $0x00
+ BYTE $0x24
+ FMOVD 0(R2), F6
+ FSUBS F1, F3
+ LDGR R8, F1
+ WFMSDB V4, V1, V6, V4
+ FMOVD 152(R9), F6
+ WFMDB V4, V4, V7
+ FMOVD 144(R9), F1
+ FMOVD 136(R9), F5
+ WFMADB V4, V1, V6, V1
+ VLEG $0, 128(R9), V16
+ FMOVD 120(R9), F6
+ WFMADB V4, V5, V6, V5
+ FMOVD 112(R9), F6
+ WFMADB V1, V7, V5, V1
+ WFMADB V4, V6, V16, V16
+ SLD $3, R0, R2
+ FMOVD 104(R9), F5
+ WORD $0xED824004 //ldeb %f8,4(%r2,%r4)
+ BYTE $0x00
+ BYTE $0x04
+ LDEBR F3, F3
+ FMOVD 96(R9), F6
+ WFMADB V4, V6, V5, V6
+ FADD F8, F3
+ WFMADB V7, V6, V16, V6
+ FMUL F7, F7
+ FMOVD 88(R9), F5
+ FMADD F7, F1, F6
+ WFMADB V4, V5, V3, V16
+ FMOVD 80(R9), F1
+ WFSDB V16, V3, V3
+ MOVD $·powtl<>+0(SB), R3
+ WFMADB V4, V6, V1, V6
+ FMADD F5, F4, F3
+ FMOVD 72(R9), F1
+ WFMADB V4, V6, V1, V6
+ WORD $0xED323000 //adb %f3,0(%r2,%r3)
+ BYTE $0x00
+ BYTE $0x1A
+ FMOVD 64(R9), F1
+ WFMADB V4, V6, V1, V6
+ MOVD $·pow_xadd<>+0(SB), R2
+ WFMADB V4, V6, V3, V4
+ FMOVD 0(R2), F5
+ WFADB V4, V16, V3
+ VLEG $0, 56(R9), V20
+ WFMSDB V2, V3, V5, V3
+ VLEG $0, 48(R9), V18
+ WFADB V3, V5, V6
+ LGDR F3, R2
+ WFMSDB V2, V16, V6, V16
+ FMOVD 40(R9), F1
+ WFMADB V2, V4, V16, V4
+ FMOVD 32(R9), F7
+ WFMDB V4, V4, V3
+ WFMADB V4, V1, V20, V1
+ WFMADB V4, V7, V18, V7
+ VLEG $0, 24(R9), V16
+ WFMADB V1, V3, V7, V1
+ FMOVD 16(R9), F5
+ WFMADB V4, V5, V16, V5
+ RISBGZ $57, $60, $3, R2, R4
+ WFMADB V3, V1, V5, V1
+ MOVD $·powtexp<>+0(SB), R3
+ WORD $0x68343000 //ld %f3,0(%r4,%r3)
+ FMADD F3, F4, F4
+ RISBGN $0, $15, $48, R2, R5
+ WFMADB V4, V1, V3, V4
+ LGDR F6, R2
+ LDGR R5, F1
+ SRAD $48, R2, R2
+ FMADD F1, F4, F1
+ RLL $16, R2, R2
+ ANDW $0x7FFF0000, R2
+ WORD $0xC22B3F71 //alfi %r2,1064370176
+ BYTE $0x00
+ BYTE $0x00
+ ORW R2, R1, R3
+ MOVW R3, R6
+ CMPBLT R6, $0, L43
+L1:
+ FMOVD F1, ret+16(FP)
+ RET
+L43:
+ LTDBR F0, F0
+ BLTU L44
+ FMOVD F0, F3
+L7:
+ MOVD $·pow_xinf<>+0(SB), R3
+ FMOVD 0(R3), F5
+ WFCEDBS V3, V5, V7
+ BVS L8
+ WFMDB V3, V2, V6
+L8:
+ WFCEDBS V2, V2, V3
+ BVS L9
+ LTDBR F2, F2
+ BEQ L26
+ MOVW R1, R6
+ CMPBLT R6, $0, L45
+L11:
+ WORD $0xC0190003 //iilf %r1,262143
+ BYTE $0xFF
+ BYTE $0xFF
+ MOVW R2, R7
+ MOVW R1, R6
+ CMPBLE R7, R6, L34
+ RISBGNZ $32, $63, $32, R5, R1
+ LGDR F6, R2
+ MOVD $powiadd<>+0(SB), R3
+ RISBGZ $60, $60, $4, R2, R2
+ WORD $0x5A123000 //a %r1,0(%r2,%r3)
+ RISBGN $0, $31, $32, R1, R5
+ LDGR R5, F1
+ FMADD F1, F4, F1
+ MOVD $powxscale<>+0(SB), R1
+ WORD $0xED121000 //mdb %f1,0(%r2,%r1)
+ BYTE $0x00
+ BYTE $0x1C
+ BR L1
+L42:
+ LTDBR F0, F0
+ BLTU L46
+ FMOVD F0, F4
+L3:
+ MOVD $·pow_x001a<>+0(SB), R2
+ WORD $0xED402000 //cdb %f4,0(%r2)
+ BYTE $0x00
+ BYTE $0x19
+ BGE L2
+ BVS L2
+ MOVD $·pow_x43f<>+0(SB), R2
+ WORD $0xED402000 //mdb %f4,0(%r2)
+ BYTE $0x00
+ BYTE $0x1C
+ WORD $0xC0298009 //iilf %r2,2148095317
+ BYTE $0x55
+ BYTE $0x55
+ LGDR F4, R3
+ RISBGNZ $32, $63, $32, R3, R3
+ SUBW R3, R2, R3
+ RISBGZ $33, $43, $0, R3, R2
+ RISBGNZ $58, $63, $50, R3, R3
+ WORD $0xE303C000 //llgc %r0,0(%r3,%r12)
+ BYTE $0x00
+ BYTE $0x90
+ SLD $3, R0, R3
+ WORD $0x5A234000 //a %r2,0(%r3,%r4)
+ BYTE $0x18 //lr %r3,%r2
+ BYTE $0x32
+ RISBGN $0, $31, $32, R3, R8
+ ADDW $0x4000000, R3
+ BLEU L5
+ RISBGZ $40, $63, $56, R3, R3
+ ORW $0x45000000, R3
+ BR L2
+L9:
+ WFCEDBS V0, V0, V4
+ BVS L35
+ FMOVD F2, F1
+ BR L1
+L46:
+ LCDBR F0, F4
+ BR L3
+L44:
+ LCDBR F0, F3
+ BR L7
+L35:
+ FMOVD F0, F1
+ BR L1
+L26:
+ FMOVD 8(R9), F1
+ BR L1
+L34:
+ FMOVD 8(R9), F4
+L19:
+ LTDBR F6, F6
+ BLEU L47
+L18:
+ WFMDB V4, V5, V1
+ BR L1
+L5:
+ RISBGZ $33, $50, $63, R3, R3
+ WORD $0xC23B4000 //alfi %r3,1073741824
+ BYTE $0x00
+ BYTE $0x00
+ RLL $24, R3, R3
+ ORW $0x45000000, R3
+ BR L2
+L45:
+ WFCEDBS V0, V0, V4
+ BVS L35
+ LTDBR F0, F0
+ BLEU L48
+ FMOVD 8(R9), F4
+L12:
+ MOVW R2, R6
+ CMPBLT R6, $0, L19
+ FMUL F4, F1
+ BR L1
+L47:
+ BLT L40
+ WFCEDBS V0, V0, V2
+ BVS L49
+L16:
+ MOVD ·pow_xnan<>+0(SB), R1
+ LDGR R1, F0
+ WFMDB V4, V0, V1
+ BR L1
+L48:
+ LGDR F0, R3
+ RISBGNZ $32, $63, $32, R3, R1
+ MOVW R1, R6
+ CMPBEQ R6, $0, L29
+ LTDBR F2, F2
+ BLTU L50
+ FMOVD F2, F4
+L14:
+ MOVD $·pow_x433<>+0(SB), R1
+ FMOVD 0(R1), F7
+ WFCHDBS V4, V7, V3
+ BEQ L15
+ WFADB V7, V4, V3
+ FSUB F7, F3
+ WFCEDBS V4, V3, V3
+ BEQ L15
+ LTDBR F0, F0
+ FMOVD 8(R9), F4
+ BNE L16
+L13:
+ LTDBR F2, F2
+ BLT L18
+L40:
+ FMOVD $0, F0
+ WFMDB V4, V0, V1
+ BR L1
+L49:
+ WFMDB V0, V4, V1
+ BR L1
+L29:
+ FMOVD 8(R9), F4
+ BR L13
+L15:
+ MOVD $·pow_x434<>+0(SB), R1
+ FMOVD 0(R1), F7
+ WFCHDBS V4, V7, V3
+ BEQ L32
+ WFADB V7, V4, V3
+ FSUB F7, F3
+ WFCEDBS V4, V3, V4
+ BEQ L32
+ FMOVD 0(R9), F4
+L17:
+ LTDBR F0, F0
+ BNE L12
+ BR L13
+L32:
+ FMOVD 8(R9), F4
+ BR L17
+L50:
+ LCDBR F2, F4
+ BR L14
+xIsOne: // Pow(1, y) = 1 for any y
+yIsOne: // Pow(x, 1) = x for any x
+posInfGeZero: // Pow(+Inf, y) = +Inf for y > 0
+ MOVD R1, ret+16(FP)
+ RET
+yIsNan: // Pow(NaN, y) = NaN
+ltZeroInt: // Pow(x, y) = NaN for finite x < 0 and finite non-integer y
+ MOVD $NaN, R2
+ MOVD R2, ret+16(FP)
+ RET
+negOnePosInf: // Pow(-1, ±Inf) = 1
+negOneNegInf:
+ MOVD $PosOne, R3
+ MOVD R3, ret+16(FP)
+ RET
+negZeroOddInt:
+ MOVD $NegInf, R3
+ MOVD R3, ret+16(FP)
+ RET
+zeroNotOdd: // Pow(±0, y) = +Inf for finite y < 0 and not an odd integer
+posZeroLtZero: // special case Pow(+0, y < 0) = +Inf
+zeroNegInf: // Pow(±0, -Inf) = +Inf
+ MOVD $PosInf, R3
+ MOVD R3, ret+16(FP)
+ RET
+gtOnePosInf: //Pow(x, +Inf) = +Inf for |x| > 1
+ltNegOnePosInf:
+ MOVD R2, ret+16(FP)
+ RET
+yIsZero: //Pow(x, ±0) = 1 for any x
+ MOVD $PosOne, R4
+ MOVD R4, ret+16(FP)
+ RET
+negZeroOddIntGtZero: // Pow(-0, y) = -0 for y an odd integer > 0
+ MOVD $NegZero, R3
+ MOVD R3, ret+16(FP)
+ RET
+zeroNotOddGtZero: // Pow(±0, y) = +0 for finite y > 0 and not an odd integer
+ MOVD $0, ret+16(FP)
+ RET
diff --git a/go/src/math/remainder.go b/go/src/math/remainder.go
new file mode 100644
index 0000000000000000000000000000000000000000..8e99345c59b79733440ae789b1a3dc265fca6c25
--- /dev/null
+++ b/go/src/math/remainder.go
@@ -0,0 +1,95 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// The original C code and the comment below are from
+// FreeBSD's /usr/src/lib/msun/src/e_remainder.c and came
+// with this notice. The go code is a simplified version of
+// the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+// __ieee754_remainder(x,y)
+// Return :
+// returns x REM y = x - [x/y]*y as if in infinite
+// precision arithmetic, where [x/y] is the (infinite bit)
+// integer nearest x/y (in half way cases, choose the even one).
+// Method :
+// Based on Mod() returning x - [x/y]chopped * y exactly.
+
+// Remainder returns the IEEE 754 floating-point remainder of x/y.
+//
+// Special cases are:
+//
+// Remainder(±Inf, y) = NaN
+// Remainder(NaN, y) = NaN
+// Remainder(x, 0) = NaN
+// Remainder(x, ±Inf) = x
+// Remainder(x, NaN) = NaN
+func Remainder(x, y float64) float64 {
+ if haveArchRemainder {
+ return archRemainder(x, y)
+ }
+ return remainder(x, y)
+}
+
+func remainder(x, y float64) float64 {
+ const (
+ Tiny = 4.45014771701440276618e-308 // 0x0020000000000000
+ HalfMax = MaxFloat64 / 2
+ )
+ // special cases
+ switch {
+ case IsNaN(x) || IsNaN(y) || IsInf(x, 0) || y == 0:
+ return NaN()
+ case IsInf(y, 0):
+ return x
+ }
+ sign := false
+ if x < 0 {
+ x = -x
+ sign = true
+ }
+ if y < 0 {
+ y = -y
+ }
+ if x == y {
+ if sign {
+ zero := 0.0
+ return -zero
+ }
+ return 0
+ }
+ if y <= HalfMax {
+ x = Mod(x, y+y) // now x < 2y
+ }
+ if y < Tiny {
+ if x+x > y {
+ x -= y
+ if x+x >= y {
+ x -= y
+ }
+ }
+ } else {
+ yHalf := 0.5 * y
+ if x > yHalf {
+ x -= y
+ if x >= yHalf {
+ x -= y
+ }
+ }
+ }
+ if sign {
+ x = -x
+ }
+ return x
+}
diff --git a/go/src/math/signbit.go b/go/src/math/signbit.go
new file mode 100644
index 0000000000000000000000000000000000000000..fe6b5a22af69ee026c96ef7ef9b2efba61d79572
--- /dev/null
+++ b/go/src/math/signbit.go
@@ -0,0 +1,10 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Signbit reports whether x is negative or negative zero.
+func Signbit(x float64) bool {
+ return int64(Float64bits(x)) < 0
+}
diff --git a/go/src/math/sin.go b/go/src/math/sin.go
new file mode 100644
index 0000000000000000000000000000000000000000..4793d7e7cd63da1f7eb9634aa6c76ba3328bca1d
--- /dev/null
+++ b/go/src/math/sin.go
@@ -0,0 +1,244 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+ Floating-point sine and cosine.
+*/
+
+// The original C code, the long comment, and the constants
+// below were from http://netlib.sandia.gov/cephes/cmath/sin.c,
+// available from http://www.netlib.org/cephes/cmath.tgz.
+// The go code is a simplified version of the original C.
+//
+// sin.c
+//
+// Circular sine
+//
+// SYNOPSIS:
+//
+// double x, y, sin();
+// y = sin( x );
+//
+// DESCRIPTION:
+//
+// Range reduction is into intervals of pi/4. The reduction error is nearly
+// eliminated by contriving an extended precision modular arithmetic.
+//
+// Two polynomial approximating functions are employed.
+// Between 0 and pi/4 the sine is approximated by
+// x + x**3 P(x**2).
+// Between pi/4 and pi/2 the cosine is represented as
+// 1 - x**2 Q(x**2).
+//
+// ACCURACY:
+//
+// Relative error:
+// arithmetic domain # trials peak rms
+// DEC 0, 10 150000 3.0e-17 7.8e-18
+// IEEE -1.07e9,+1.07e9 130000 2.1e-16 5.4e-17
+//
+// Partial loss of accuracy begins to occur at x = 2**30 = 1.074e9. The loss
+// is not gradual, but jumps suddenly to about 1 part in 10e7. Results may
+// be meaningless for x > 2**49 = 5.6e14.
+//
+// cos.c
+//
+// Circular cosine
+//
+// SYNOPSIS:
+//
+// double x, y, cos();
+// y = cos( x );
+//
+// DESCRIPTION:
+//
+// Range reduction is into intervals of pi/4. The reduction error is nearly
+// eliminated by contriving an extended precision modular arithmetic.
+//
+// Two polynomial approximating functions are employed.
+// Between 0 and pi/4 the cosine is approximated by
+// 1 - x**2 Q(x**2).
+// Between pi/4 and pi/2 the sine is represented as
+// x + x**3 P(x**2).
+//
+// ACCURACY:
+//
+// Relative error:
+// arithmetic domain # trials peak rms
+// IEEE -1.07e9,+1.07e9 130000 2.1e-16 5.4e-17
+// DEC 0,+1.07e9 17000 3.0e-17 7.2e-18
+//
+// Cephes Math Library Release 2.8: June, 2000
+// Copyright 1984, 1987, 1989, 1992, 2000 by Stephen L. Moshier
+//
+// The readme file at http://netlib.sandia.gov/cephes/ says:
+// Some software in this archive may be from the book _Methods and
+// Programs for Mathematical Functions_ (Prentice-Hall or Simon & Schuster
+// International, 1989) or from the Cephes Mathematical Library, a
+// commercial product. In either event, it is copyrighted by the author.
+// What you see here may be used freely but it comes with no support or
+// guarantee.
+//
+// The two known misprints in the book are repaired here in the
+// source listings for the gamma function and the incomplete beta
+// integral.
+//
+// Stephen L. Moshier
+// moshier@na-net.ornl.gov
+
+// sin coefficients
+var _sin = [...]float64{
+ 1.58962301576546568060e-10, // 0x3de5d8fd1fd19ccd
+ -2.50507477628578072866e-8, // 0xbe5ae5e5a9291f5d
+ 2.75573136213857245213e-6, // 0x3ec71de3567d48a1
+ -1.98412698295895385996e-4, // 0xbf2a01a019bfdf03
+ 8.33333333332211858878e-3, // 0x3f8111111110f7d0
+ -1.66666666666666307295e-1, // 0xbfc5555555555548
+}
+
+// cos coefficients
+var _cos = [...]float64{
+ -1.13585365213876817300e-11, // 0xbda8fa49a0861a9b
+ 2.08757008419747316778e-9, // 0x3e21ee9d7b4e3f05
+ -2.75573141792967388112e-7, // 0xbe927e4f7eac4bc6
+ 2.48015872888517045348e-5, // 0x3efa01a019c844f5
+ -1.38888888888730564116e-3, // 0xbf56c16c16c14f91
+ 4.16666666666665929218e-2, // 0x3fa555555555554b
+}
+
+// Cos returns the cosine of the radian argument x.
+//
+// Special cases are:
+//
+// Cos(±Inf) = NaN
+// Cos(NaN) = NaN
+func Cos(x float64) float64 {
+ if haveArchCos {
+ return archCos(x)
+ }
+ return cos(x)
+}
+
+func cos(x float64) float64 {
+ const (
+ PI4A = 7.85398125648498535156e-1 // 0x3fe921fb40000000, Pi/4 split into three parts
+ PI4B = 3.77489470793079817668e-8 // 0x3e64442d00000000,
+ PI4C = 2.69515142907905952645e-15 // 0x3ce8469898cc5170,
+ )
+ // special cases
+ switch {
+ case IsNaN(x) || IsInf(x, 0):
+ return NaN()
+ }
+
+ // make argument positive
+ sign := false
+ x = Abs(x)
+
+ var j uint64
+ var y, z float64
+ if x >= reduceThreshold {
+ j, z = trigReduce(x)
+ } else {
+ j = uint64(x * (4 / Pi)) // integer part of x/(Pi/4), as integer for tests on the phase angle
+ y = float64(j) // integer part of x/(Pi/4), as float
+
+ // map zeros to origin
+ if j&1 == 1 {
+ j++
+ y++
+ }
+ j &= 7 // octant modulo 2Pi radians (360 degrees)
+ z = ((x - y*PI4A) - y*PI4B) - y*PI4C // Extended precision modular arithmetic
+ }
+
+ if j > 3 {
+ j -= 4
+ sign = !sign
+ }
+ if j > 1 {
+ sign = !sign
+ }
+
+ zz := z * z
+ if j == 1 || j == 2 {
+ y = z + z*zz*((((((_sin[0]*zz)+_sin[1])*zz+_sin[2])*zz+_sin[3])*zz+_sin[4])*zz+_sin[5])
+ } else {
+ y = 1.0 - 0.5*zz + zz*zz*((((((_cos[0]*zz)+_cos[1])*zz+_cos[2])*zz+_cos[3])*zz+_cos[4])*zz+_cos[5])
+ }
+ if sign {
+ y = -y
+ }
+ return y
+}
+
+// Sin returns the sine of the radian argument x.
+//
+// Special cases are:
+//
+// Sin(±0) = ±0
+// Sin(±Inf) = NaN
+// Sin(NaN) = NaN
+func Sin(x float64) float64 {
+ if haveArchSin {
+ return archSin(x)
+ }
+ return sin(x)
+}
+
+func sin(x float64) float64 {
+ const (
+ PI4A = 7.85398125648498535156e-1 // 0x3fe921fb40000000, Pi/4 split into three parts
+ PI4B = 3.77489470793079817668e-8 // 0x3e64442d00000000,
+ PI4C = 2.69515142907905952645e-15 // 0x3ce8469898cc5170,
+ )
+ // special cases
+ switch {
+ case x == 0 || IsNaN(x):
+ return x // return ±0 || NaN()
+ case IsInf(x, 0):
+ return NaN()
+ }
+
+ // make argument positive but save the sign
+ sign := false
+ if x < 0 {
+ x = -x
+ sign = true
+ }
+
+ var j uint64
+ var y, z float64
+ if x >= reduceThreshold {
+ j, z = trigReduce(x)
+ } else {
+ j = uint64(x * (4 / Pi)) // integer part of x/(Pi/4), as integer for tests on the phase angle
+ y = float64(j) // integer part of x/(Pi/4), as float
+
+ // map zeros to origin
+ if j&1 == 1 {
+ j++
+ y++
+ }
+ j &= 7 // octant modulo 2Pi radians (360 degrees)
+ z = ((x - y*PI4A) - y*PI4B) - y*PI4C // Extended precision modular arithmetic
+ }
+ // reflect in x axis
+ if j > 3 {
+ sign = !sign
+ j -= 4
+ }
+ zz := z * z
+ if j == 1 || j == 2 {
+ y = 1.0 - 0.5*zz + zz*zz*((((((_cos[0]*zz)+_cos[1])*zz+_cos[2])*zz+_cos[3])*zz+_cos[4])*zz+_cos[5])
+ } else {
+ y = z + z*zz*((((((_sin[0]*zz)+_sin[1])*zz+_sin[2])*zz+_sin[3])*zz+_sin[4])*zz+_sin[5])
+ }
+ if sign {
+ y = -y
+ }
+ return y
+}
diff --git a/go/src/math/sin_s390x.s b/go/src/math/sin_s390x.s
new file mode 100644
index 0000000000000000000000000000000000000000..79d564b938ec2881296957e159c823f187a12f7b
--- /dev/null
+++ b/go/src/math/sin_s390x.s
@@ -0,0 +1,369 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// Various constants
+DATA sincosxnan<>+0(SB)/8, $0x7ff8000000000000
+GLOBL sincosxnan<>+0(SB), RODATA, $8
+DATA sincosxlim<>+0(SB)/8, $0x432921fb54442d19
+GLOBL sincosxlim<>+0(SB), RODATA, $8
+DATA sincosxadd<>+0(SB)/8, $0xc338000000000000
+GLOBL sincosxadd<>+0(SB), RODATA, $8
+DATA sincosxpi2l<>+0(SB)/8, $0.108285667392191389e-31
+GLOBL sincosxpi2l<>+0(SB), RODATA, $8
+DATA sincosxpi2m<>+0(SB)/8, $0.612323399573676480e-16
+GLOBL sincosxpi2m<>+0(SB), RODATA, $8
+DATA sincosxpi2h<>+0(SB)/8, $0.157079632679489656e+01
+GLOBL sincosxpi2h<>+0(SB), RODATA, $8
+DATA sincosrpi2<>+0(SB)/8, $0.636619772367581341e+00
+GLOBL sincosrpi2<>+0(SB), RODATA, $8
+
+// Minimax polynomial approximations
+DATA sincosc0<>+0(SB)/8, $0.100000000000000000E+01
+GLOBL sincosc0<>+0(SB), RODATA, $8
+DATA sincosc1<>+0(SB)/8, $-.499999999999999833E+00
+GLOBL sincosc1<>+0(SB), RODATA, $8
+DATA sincosc2<>+0(SB)/8, $0.416666666666625843E-01
+GLOBL sincosc2<>+0(SB), RODATA, $8
+DATA sincosc3<>+0(SB)/8, $-.138888888885498984E-02
+GLOBL sincosc3<>+0(SB), RODATA, $8
+DATA sincosc4<>+0(SB)/8, $0.248015871681607202E-04
+GLOBL sincosc4<>+0(SB), RODATA, $8
+DATA sincosc5<>+0(SB)/8, $-.275572911309937875E-06
+GLOBL sincosc5<>+0(SB), RODATA, $8
+DATA sincosc6<>+0(SB)/8, $0.208735047247632818E-08
+GLOBL sincosc6<>+0(SB), RODATA, $8
+DATA sincosc7<>+0(SB)/8, $-.112753632738365317E-10
+GLOBL sincosc7<>+0(SB), RODATA, $8
+DATA sincoss0<>+0(SB)/8, $0.100000000000000000E+01
+GLOBL sincoss0<>+0(SB), RODATA, $8
+DATA sincoss1<>+0(SB)/8, $-.166666666666666657E+00
+GLOBL sincoss1<>+0(SB), RODATA, $8
+DATA sincoss2<>+0(SB)/8, $0.833333333333309209E-02
+GLOBL sincoss2<>+0(SB), RODATA, $8
+DATA sincoss3<>+0(SB)/8, $-.198412698410701448E-03
+GLOBL sincoss3<>+0(SB), RODATA, $8
+DATA sincoss4<>+0(SB)/8, $0.275573191453906794E-05
+GLOBL sincoss4<>+0(SB), RODATA, $8
+DATA sincoss5<>+0(SB)/8, $-.250520918387633290E-07
+GLOBL sincoss5<>+0(SB), RODATA, $8
+DATA sincoss6<>+0(SB)/8, $0.160571285514715856E-09
+GLOBL sincoss6<>+0(SB), RODATA, $8
+DATA sincoss7<>+0(SB)/8, $-.753213484933210972E-12
+GLOBL sincoss7<>+0(SB), RODATA, $8
+
+// Sin returns the sine of the radian argument x.
+//
+// Special cases are:
+// Sin(±0) = ±0
+// Sin(±Inf) = NaN
+// Sin(NaN) = NaN
+// The algorithm used is minimax polynomial approximation.
+// with coefficients determined with a Remez exchange algorithm.
+
+TEXT ·sinAsm(SB),NOSPLIT,$0-16
+ FMOVD x+0(FP), F0
+ //special case Sin(±0) = ±0
+ FMOVD $(0.0), F1
+ FCMPU F0, F1
+ BEQ sinIsZero
+ LTDBR F0, F0
+ BLTU L17
+ FMOVD F0, F5
+L2:
+ MOVD $sincosxlim<>+0(SB), R1
+ FMOVD 0(R1), F1
+ FCMPU F5, F1
+ BGT L16
+ MOVD $sincoss7<>+0(SB), R1
+ FMOVD 0(R1), F4
+ MOVD $sincoss6<>+0(SB), R1
+ FMOVD 0(R1), F1
+ MOVD $sincoss5<>+0(SB), R1
+ VLEG $0, 0(R1), V18
+ MOVD $sincoss4<>+0(SB), R1
+ FMOVD 0(R1), F6
+ MOVD $sincoss2<>+0(SB), R1
+ VLEG $0, 0(R1), V16
+ MOVD $sincoss3<>+0(SB), R1
+ FMOVD 0(R1), F7
+ MOVD $sincoss1<>+0(SB), R1
+ FMOVD 0(R1), F3
+ MOVD $sincoss0<>+0(SB), R1
+ FMOVD 0(R1), F2
+ WFCHDBS V2, V5, V2
+ BEQ L18
+ MOVD $sincosrpi2<>+0(SB), R1
+ FMOVD 0(R1), F3
+ MOVD $sincosxadd<>+0(SB), R1
+ FMOVD 0(R1), F2
+ WFMSDB V0, V3, V2, V3
+ FMOVD 0(R1), F6
+ FADD F3, F6
+ MOVD $sincosxpi2h<>+0(SB), R1
+ FMOVD 0(R1), F2
+ FMSUB F2, F6, F0
+ MOVD $sincosxpi2m<>+0(SB), R1
+ FMOVD 0(R1), F4
+ FMADD F4, F6, F0
+ MOVD $sincosxpi2l<>+0(SB), R1
+ WFMDB V0, V0, V1
+ FMOVD 0(R1), F7
+ WFMDB V1, V1, V2
+ LGDR F3, R1
+ MOVD $sincosxlim<>+0(SB), R2
+ TMLL R1, $1
+ BEQ L6
+ FMOVD 0(R2), F0
+ WFCHDBS V0, V5, V0
+ BNE L14
+ MOVD $sincosc7<>+0(SB), R2
+ FMOVD 0(R2), F0
+ MOVD $sincosc6<>+0(SB), R2
+ FMOVD 0(R2), F4
+ MOVD $sincosc5<>+0(SB), R2
+ WFMADB V1, V0, V4, V0
+ FMOVD 0(R2), F6
+ MOVD $sincosc4<>+0(SB), R2
+ WFMADB V1, V0, V6, V0
+ FMOVD 0(R2), F4
+ MOVD $sincosc2<>+0(SB), R2
+ FMOVD 0(R2), F6
+ WFMADB V2, V4, V6, V4
+ MOVD $sincosc3<>+0(SB), R2
+ FMOVD 0(R2), F3
+ MOVD $sincosc1<>+0(SB), R2
+ WFMADB V2, V0, V3, V0
+ FMOVD 0(R2), F6
+ WFMADB V1, V4, V6, V4
+ TMLL R1, $2
+ WFMADB V2, V0, V4, V0
+ MOVD $sincosc0<>+0(SB), R1
+ FMOVD 0(R1), F2
+ WFMADB V1, V0, V2, V0
+ BNE L15
+ FMOVD F0, ret+8(FP)
+ RET
+
+L6:
+ FMOVD 0(R2), F4
+ WFCHDBS V4, V5, V4
+ BNE L14
+ MOVD $sincoss7<>+0(SB), R2
+ FMOVD 0(R2), F4
+ MOVD $sincoss6<>+0(SB), R2
+ FMOVD 0(R2), F3
+ MOVD $sincoss5<>+0(SB), R2
+ WFMADB V1, V4, V3, V4
+ WFMADB V6, V7, V0, V6
+ FMOVD 0(R2), F0
+ MOVD $sincoss4<>+0(SB), R2
+ FMADD F4, F1, F0
+ FMOVD 0(R2), F3
+ MOVD $sincoss2<>+0(SB), R2
+ FMOVD 0(R2), F4
+ MOVD $sincoss3<>+0(SB), R2
+ WFMADB V2, V3, V4, V3
+ FMOVD 0(R2), F4
+ MOVD $sincoss1<>+0(SB), R2
+ WFMADB V2, V0, V4, V0
+ FMOVD 0(R2), F4
+ WFMADB V1, V3, V4, V3
+ FNEG F6, F4
+ WFMADB V2, V0, V3, V2
+ WFMDB V4, V1, V0
+ TMLL R1, $2
+ WFMSDB V0, V2, V6, V0
+ BNE L15
+ FMOVD F0, ret+8(FP)
+ RET
+
+L14:
+ MOVD $sincosxnan<>+0(SB), R1
+ FMOVD 0(R1), F0
+ FMOVD F0, ret+8(FP)
+ RET
+
+L18:
+ WFMDB V0, V0, V2
+ WFMADB V2, V4, V1, V4
+ WFMDB V2, V2, V1
+ WFMADB V2, V4, V18, V4
+ WFMADB V1, V6, V16, V6
+ WFMADB V1, V4, V7, V4
+ WFMADB V2, V6, V3, V6
+ FMUL F0, F2
+ WFMADB V1, V4, V6, V4
+ FMADD F4, F2, F0
+ FMOVD F0, ret+8(FP)
+ RET
+
+L17:
+ FNEG F0, F5
+ BR L2
+L15:
+ FNEG F0, F0
+ FMOVD F0, ret+8(FP)
+ RET
+
+
+L16:
+ BR ·sin(SB) //tail call
+sinIsZero:
+ FMOVD F0, ret+8(FP)
+ RET
+
+// Cos returns the cosine of the radian argument.
+//
+// Special cases are:
+// Cos(±Inf) = NaN
+// Cos(NaN) = NaN
+// The algorithm used is minimax polynomial approximation.
+// with coefficients determined with a Remez exchange algorithm.
+
+TEXT ·cosAsm(SB),NOSPLIT,$0-16
+ FMOVD x+0(FP), F0
+ LTDBR F0, F0
+ BLTU L35
+ FMOVD F0, F1
+L21:
+ MOVD $sincosxlim<>+0(SB), R1
+ FMOVD 0(R1), F2
+ FCMPU F1, F2
+ BGT L30
+ MOVD $sincosc7<>+0(SB), R1
+ FMOVD 0(R1), F4
+ MOVD $sincosc6<>+0(SB), R1
+ VLEG $0, 0(R1), V20
+ MOVD $sincosc5<>+0(SB), R1
+ VLEG $0, 0(R1), V18
+ MOVD $sincosc4<>+0(SB), R1
+ FMOVD 0(R1), F6
+ MOVD $sincosc2<>+0(SB), R1
+ VLEG $0, 0(R1), V16
+ MOVD $sincosc3<>+0(SB), R1
+ FMOVD 0(R1), F7
+ MOVD $sincosc1<>+0(SB), R1
+ FMOVD 0(R1), F5
+ MOVD $sincosrpi2<>+0(SB), R1
+ FMOVD 0(R1), F2
+ MOVD $sincosxadd<>+0(SB), R1
+ FMOVD 0(R1), F3
+ MOVD $sincoss0<>+0(SB), R1
+ WFMSDB V0, V2, V3, V2
+ FMOVD 0(R1), F3
+ WFCHDBS V3, V1, V3
+ LGDR F2, R1
+ BEQ L36
+ MOVD $sincosxadd<>+0(SB), R2
+ FMOVD 0(R2), F4
+ FADD F2, F4
+ MOVD $sincosxpi2h<>+0(SB), R2
+ FMOVD 0(R2), F2
+ WFMSDB V4, V2, V0, V2
+ MOVD $sincosxpi2m<>+0(SB), R2
+ FMOVD 0(R2), F0
+ WFMADB V4, V0, V2, V0
+ MOVD $sincosxpi2l<>+0(SB), R2
+ WFMDB V0, V0, V2
+ FMOVD 0(R2), F5
+ WFMDB V2, V2, V6
+ MOVD $sincosxlim<>+0(SB), R2
+ TMLL R1, $1
+ BNE L25
+ FMOVD 0(R2), F0
+ WFCHDBS V0, V1, V0
+ BNE L33
+ MOVD $sincosc7<>+0(SB), R2
+ FMOVD 0(R2), F0
+ MOVD $sincosc6<>+0(SB), R2
+ FMOVD 0(R2), F4
+ MOVD $sincosc5<>+0(SB), R2
+ WFMADB V2, V0, V4, V0
+ FMOVD 0(R2), F1
+ MOVD $sincosc4<>+0(SB), R2
+ WFMADB V2, V0, V1, V0
+ FMOVD 0(R2), F4
+ MOVD $sincosc2<>+0(SB), R2
+ FMOVD 0(R2), F1
+ WFMADB V6, V4, V1, V4
+ MOVD $sincosc3<>+0(SB), R2
+ FMOVD 0(R2), F3
+ MOVD $sincosc1<>+0(SB), R2
+ WFMADB V6, V0, V3, V0
+ FMOVD 0(R2), F1
+ WFMADB V2, V4, V1, V4
+ TMLL R1, $2
+ WFMADB V6, V0, V4, V0
+ MOVD $sincosc0<>+0(SB), R1
+ FMOVD 0(R1), F4
+ WFMADB V2, V0, V4, V0
+ BNE L34
+ FMOVD F0, ret+8(FP)
+ RET
+
+L25:
+ FMOVD 0(R2), F3
+ WFCHDBS V3, V1, V1
+ BNE L33
+ MOVD $sincoss7<>+0(SB), R2
+ FMOVD 0(R2), F1
+ MOVD $sincoss6<>+0(SB), R2
+ FMOVD 0(R2), F3
+ MOVD $sincoss5<>+0(SB), R2
+ WFMADB V2, V1, V3, V1
+ FMOVD 0(R2), F3
+ MOVD $sincoss4<>+0(SB), R2
+ WFMADB V2, V1, V3, V1
+ FMOVD 0(R2), F3
+ MOVD $sincoss2<>+0(SB), R2
+ FMOVD 0(R2), F7
+ WFMADB V6, V3, V7, V3
+ MOVD $sincoss3<>+0(SB), R2
+ FMADD F5, F4, F0
+ FMOVD 0(R2), F4
+ MOVD $sincoss1<>+0(SB), R2
+ FMADD F1, F6, F4
+ FMOVD 0(R2), F1
+ FMADD F3, F2, F1
+ FMUL F0, F2
+ WFMADB V6, V4, V1, V6
+ TMLL R1, $2
+ FMADD F6, F2, F0
+ BNE L34
+ FMOVD F0, ret+8(FP)
+ RET
+
+L33:
+ MOVD $sincosxnan<>+0(SB), R1
+ FMOVD 0(R1), F0
+ FMOVD F0, ret+8(FP)
+ RET
+
+L36:
+ FMUL F0, F0
+ MOVD $sincosc0<>+0(SB), R1
+ WFMDB V0, V0, V1
+ WFMADB V0, V4, V20, V4
+ WFMADB V1, V6, V16, V6
+ WFMADB V0, V4, V18, V4
+ WFMADB V0, V6, V5, V6
+ WFMADB V1, V4, V7, V4
+ FMOVD 0(R1), F2
+ WFMADB V1, V4, V6, V4
+ WFMADB V0, V4, V2, V0
+ FMOVD F0, ret+8(FP)
+ RET
+
+L35:
+ FNEG F0, F1
+ BR L21
+L34:
+ FNEG F0, F0
+ FMOVD F0, ret+8(FP)
+ RET
+
+L30:
+ BR ·cos(SB) //tail call
diff --git a/go/src/math/sincos.go b/go/src/math/sincos.go
new file mode 100644
index 0000000000000000000000000000000000000000..e3fb96094fa75f33727cd676bb937b17233707d9
--- /dev/null
+++ b/go/src/math/sincos.go
@@ -0,0 +1,73 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// Coefficients _sin[] and _cos[] are found in pkg/math/sin.go.
+
+// Sincos returns Sin(x), Cos(x).
+//
+// Special cases are:
+//
+// Sincos(±0) = ±0, 1
+// Sincos(±Inf) = NaN, NaN
+// Sincos(NaN) = NaN, NaN
+func Sincos(x float64) (sin, cos float64) {
+ const (
+ PI4A = 7.85398125648498535156e-1 // 0x3fe921fb40000000, Pi/4 split into three parts
+ PI4B = 3.77489470793079817668e-8 // 0x3e64442d00000000,
+ PI4C = 2.69515142907905952645e-15 // 0x3ce8469898cc5170,
+ )
+ // special cases
+ switch {
+ case x == 0:
+ return x, 1 // return ±0.0, 1.0
+ case IsNaN(x) || IsInf(x, 0):
+ return NaN(), NaN()
+ }
+
+ // make argument positive
+ sinSign, cosSign := false, false
+ if x < 0 {
+ x = -x
+ sinSign = true
+ }
+
+ var j uint64
+ var y, z float64
+ if x >= reduceThreshold {
+ j, z = trigReduce(x)
+ } else {
+ j = uint64(x * (4 / Pi)) // integer part of x/(Pi/4), as integer for tests on the phase angle
+ y = float64(j) // integer part of x/(Pi/4), as float
+
+ if j&1 == 1 { // map zeros to origin
+ j++
+ y++
+ }
+ j &= 7 // octant modulo 2Pi radians (360 degrees)
+ z = ((x - y*PI4A) - y*PI4B) - y*PI4C // Extended precision modular arithmetic
+ }
+ if j > 3 { // reflect in x axis
+ j -= 4
+ sinSign, cosSign = !sinSign, !cosSign
+ }
+ if j > 1 {
+ cosSign = !cosSign
+ }
+
+ zz := z * z
+ cos = 1.0 - 0.5*zz + zz*zz*((((((_cos[0]*zz)+_cos[1])*zz+_cos[2])*zz+_cos[3])*zz+_cos[4])*zz+_cos[5])
+ sin = z + z*zz*((((((_sin[0]*zz)+_sin[1])*zz+_sin[2])*zz+_sin[3])*zz+_sin[4])*zz+_sin[5])
+ if j == 1 || j == 2 {
+ sin, cos = cos, sin
+ }
+ if cosSign {
+ cos = -cos
+ }
+ if sinSign {
+ sin = -sin
+ }
+ return
+}
diff --git a/go/src/math/sinh.go b/go/src/math/sinh.go
new file mode 100644
index 0000000000000000000000000000000000000000..78b3c299d668931fb0289328a99b0ab5ce29f723
--- /dev/null
+++ b/go/src/math/sinh.go
@@ -0,0 +1,93 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+/*
+ Floating-point hyperbolic sine and cosine.
+
+ The exponential func is called for arguments
+ greater in magnitude than 0.5.
+
+ A series is used for arguments smaller in magnitude than 0.5.
+
+ Cosh(x) is computed from the exponential func for
+ all arguments.
+*/
+
+// Sinh returns the hyperbolic sine of x.
+//
+// Special cases are:
+//
+// Sinh(±0) = ±0
+// Sinh(±Inf) = ±Inf
+// Sinh(NaN) = NaN
+func Sinh(x float64) float64 {
+ if haveArchSinh {
+ return archSinh(x)
+ }
+ return sinh(x)
+}
+
+func sinh(x float64) float64 {
+ // The coefficients are #2029 from Hart & Cheney. (20.36D)
+ const (
+ P0 = -0.6307673640497716991184787251e+6
+ P1 = -0.8991272022039509355398013511e+5
+ P2 = -0.2894211355989563807284660366e+4
+ P3 = -0.2630563213397497062819489e+2
+ Q0 = -0.6307673640497716991212077277e+6
+ Q1 = 0.1521517378790019070696485176e+5
+ Q2 = -0.173678953558233699533450911e+3
+ )
+
+ sign := false
+ if x < 0 {
+ x = -x
+ sign = true
+ }
+
+ var temp float64
+ switch {
+ case x > 21:
+ temp = Exp(x) * 0.5
+
+ case x > 0.5:
+ ex := Exp(x)
+ temp = (ex - 1/ex) * 0.5
+
+ default:
+ sq := x * x
+ temp = (((P3*sq+P2)*sq+P1)*sq + P0) * x
+ temp = temp / (((sq+Q2)*sq+Q1)*sq + Q0)
+ }
+
+ if sign {
+ temp = -temp
+ }
+ return temp
+}
+
+// Cosh returns the hyperbolic cosine of x.
+//
+// Special cases are:
+//
+// Cosh(±0) = 1
+// Cosh(±Inf) = +Inf
+// Cosh(NaN) = NaN
+func Cosh(x float64) float64 {
+ if haveArchCosh {
+ return archCosh(x)
+ }
+ return cosh(x)
+}
+
+func cosh(x float64) float64 {
+ x = Abs(x)
+ if x > 21 {
+ return Exp(x) * 0.5
+ }
+ ex := Exp(x)
+ return (ex + 1/ex) * 0.5
+}
diff --git a/go/src/math/sinh_s390x.s b/go/src/math/sinh_s390x.s
new file mode 100644
index 0000000000000000000000000000000000000000..d684968a3a87e684c80d166369fc3dc229a1186c
--- /dev/null
+++ b/go/src/math/sinh_s390x.s
@@ -0,0 +1,251 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+
+#include "textflag.h"
+
+// Constants
+DATA sinhrodataL21<>+0(SB)/8, $0.231904681384629956E-16
+DATA sinhrodataL21<>+8(SB)/8, $0.693147180559945286E+00
+DATA sinhrodataL21<>+16(SB)/8, $704.E0
+GLOBL sinhrodataL21<>+0(SB), RODATA, $24
+DATA sinhrlog2<>+0(SB)/8, $0x3ff7154760000000
+GLOBL sinhrlog2<>+0(SB), RODATA, $8
+DATA sinhxinf<>+0(SB)/8, $0x7ff0000000000000
+GLOBL sinhxinf<>+0(SB), RODATA, $8
+DATA sinhxinit<>+0(SB)/8, $0x3ffb504f333f9de6
+GLOBL sinhxinit<>+0(SB), RODATA, $8
+DATA sinhxlim1<>+0(SB)/8, $800.E0
+GLOBL sinhxlim1<>+0(SB), RODATA, $8
+DATA sinhxadd<>+0(SB)/8, $0xc3200001610007fb
+GLOBL sinhxadd<>+0(SB), RODATA, $8
+DATA sinhx4ff<>+0(SB)/8, $0x4ff0000000000000
+GLOBL sinhx4ff<>+0(SB), RODATA, $8
+
+// Minimax polynomial approximations
+DATA sinhe0<>+0(SB)/8, $0.11715728752538099300E+01
+GLOBL sinhe0<>+0(SB), RODATA, $8
+DATA sinhe1<>+0(SB)/8, $0.11715728752538099300E+01
+GLOBL sinhe1<>+0(SB), RODATA, $8
+DATA sinhe2<>+0(SB)/8, $0.58578643762688526692E+00
+GLOBL sinhe2<>+0(SB), RODATA, $8
+DATA sinhe3<>+0(SB)/8, $0.19526214587563004497E+00
+GLOBL sinhe3<>+0(SB), RODATA, $8
+DATA sinhe4<>+0(SB)/8, $0.48815536475176217404E-01
+GLOBL sinhe4<>+0(SB), RODATA, $8
+DATA sinhe5<>+0(SB)/8, $0.97631072948627397816E-02
+GLOBL sinhe5<>+0(SB), RODATA, $8
+DATA sinhe6<>+0(SB)/8, $0.16271839297756073153E-02
+GLOBL sinhe6<>+0(SB), RODATA, $8
+DATA sinhe7<>+0(SB)/8, $0.23245485387271142509E-03
+GLOBL sinhe7<>+0(SB), RODATA, $8
+DATA sinhe8<>+0(SB)/8, $0.29080955860869629131E-04
+GLOBL sinhe8<>+0(SB), RODATA, $8
+DATA sinhe9<>+0(SB)/8, $0.32311267157667725278E-05
+GLOBL sinhe9<>+0(SB), RODATA, $8
+
+// Sinh returns the hyperbolic sine of the argument.
+//
+// Special cases are:
+// Sinh(±0) = ±0
+// Sinh(±Inf) = ±Inf
+// Sinh(NaN) = NaN
+// The algorithm used is minimax polynomial approximation
+// with coefficients determined with a Remez exchange algorithm.
+
+TEXT ·sinhAsm(SB),NOSPLIT,$0-16
+ FMOVD x+0(FP), F0
+ //special case Sinh(±0) = ±0
+ FMOVD $(0.0), F1
+ FCMPU F0, F1
+ BEQ sinhIsZero
+ //special case Sinh(±Inf) = ±Inf
+ FMOVD $1.797693134862315708145274237317043567981e+308, F1
+ FCMPU F1, F0
+ BLEU sinhIsInf
+ FMOVD $-1.797693134862315708145274237317043567981e+308, F1
+ FCMPU F1, F0
+ BGT sinhIsInf
+
+ MOVD $sinhrodataL21<>+0(SB), R5
+ LTDBR F0, F0
+ MOVD sinhxinit<>+0(SB), R1
+ FMOVD F0, F4
+ MOVD R1, R3
+ BLTU L19
+ FMOVD F0, F2
+L2:
+ WORD $0xED205010 //cdb %f2,.L22-.L21(%r5)
+ BYTE $0x00
+ BYTE $0x19
+ BGE L15 //jnl .L15
+ BVS L15
+ WFCEDBS V2, V2, V0
+ BEQ L20
+L12:
+ FMOVD F4, F0
+ FMOVD F0, ret+8(FP)
+ RET
+
+L15:
+ WFCEDBS V2, V2, V0
+ BVS L12
+ MOVD $sinhxlim1<>+0(SB), R2
+ FMOVD 0(R2), F0
+ WFCHDBS V0, V2, V0
+ BEQ L6
+ WFCHEDBS V4, V2, V6
+ MOVD $sinhxinf<>+0(SB), R1
+ FMOVD 0(R1), F0
+ BNE LEXITTAGsinh
+ WFCHDBS V2, V4, V2
+ BNE L16
+ FNEG F0, F0
+ FMOVD F0, ret+8(FP)
+ RET
+
+L19:
+ FNEG F0, F2
+ BR L2
+L6:
+ MOVD $sinhxadd<>+0(SB), R2
+ FMOVD 0(R2), F0
+ MOVD sinhrlog2<>+0(SB), R2
+ LDGR R2, F6
+ WFMSDB V4, V6, V0, V16
+ FMOVD sinhrodataL21<>+8(SB), F6
+ WFADB V0, V16, V0
+ FMOVD sinhrodataL21<>+0(SB), F3
+ WFMSDB V0, V6, V4, V6
+ MOVD $sinhe9<>+0(SB), R2
+ WFMADB V0, V3, V6, V0
+ FMOVD 0(R2), F1
+ MOVD $sinhe7<>+0(SB), R2
+ WFMDB V0, V0, V6
+ FMOVD 0(R2), F5
+ MOVD $sinhe8<>+0(SB), R2
+ FMOVD 0(R2), F3
+ MOVD $sinhe6<>+0(SB), R2
+ WFMADB V6, V1, V5, V1
+ FMOVD 0(R2), F5
+ MOVD $sinhe5<>+0(SB), R2
+ FMOVD 0(R2), F7
+ MOVD $sinhe3<>+0(SB), R2
+ WFMADB V6, V3, V5, V3
+ FMOVD 0(R2), F5
+ MOVD $sinhe4<>+0(SB), R2
+ WFMADB V6, V7, V5, V7
+ FMOVD 0(R2), F5
+ MOVD $sinhe2<>+0(SB), R2
+ VLEG $0, 0(R2), V20
+ WFMDB V6, V6, V18
+ WFMADB V6, V5, V20, V5
+ WFMADB V1, V18, V7, V1
+ FNEG F0, F0
+ WFMADB V3, V18, V5, V3
+ MOVD $sinhe1<>+0(SB), R3
+ WFCEDBS V2, V4, V2
+ FMOVD 0(R3), F5
+ MOVD $sinhe0<>+0(SB), R3
+ WFMADB V6, V1, V5, V1
+ FMOVD 0(R3), F5
+ VLGVG $0, V16, R2
+ WFMADB V6, V3, V5, V6
+ RLL $3, R2, R2
+ RISBGN $0, $15, $48, R2, R1
+ BEQ L9
+ WFMSDB V0, V1, V6, V0
+ MOVD $sinhx4ff<>+0(SB), R3
+ FNEG F0, F0
+ FMOVD 0(R3), F2
+ FMUL F2, F0
+ ANDW $0xFFFF, R2
+ WORD $0xA53FEFB6 //llill %r3,61366
+ SUBW R2, R3, R2
+ RISBGN $0, $15, $48, R2, R1
+ LDGR R1, F2
+ FMUL F2, F0
+ FMOVD F0, ret+8(FP)
+ RET
+
+L20:
+ MOVD $sinhxadd<>+0(SB), R2
+ FMOVD 0(R2), F2
+ MOVD sinhrlog2<>+0(SB), R2
+ LDGR R2, F0
+ WFMSDB V4, V0, V2, V6
+ FMOVD sinhrodataL21<>+8(SB), F0
+ FADD F6, F2
+ MOVD $sinhe9<>+0(SB), R2
+ FMSUB F0, F2, F4
+ FMOVD 0(R2), F1
+ FMOVD sinhrodataL21<>+0(SB), F3
+ MOVD $sinhe7<>+0(SB), R2
+ FMADD F3, F2, F4
+ FMOVD 0(R2), F0
+ MOVD $sinhe8<>+0(SB), R2
+ WFMDB V4, V4, V2
+ FMOVD 0(R2), F3
+ MOVD $sinhe6<>+0(SB), R2
+ FMOVD 0(R2), F5
+ LGDR F6, R2
+ RLL $3, R2, R2
+ RISBGN $0, $15, $48, R2, R1
+ WFMADB V2, V1, V0, V1
+ LDGR R1, F0
+ MOVD $sinhe5<>+0(SB), R1
+ WFMADB V2, V3, V5, V3
+ FMOVD 0(R1), F5
+ MOVD $sinhe3<>+0(SB), R1
+ FMOVD 0(R1), F6
+ WFMDB V2, V2, V7
+ WFMADB V2, V5, V6, V5
+ WORD $0xA7487FB6 //lhi %r4,32694
+ FNEG F4, F4
+ ANDW $0xFFFF, R2
+ SUBW R2, R4, R2
+ RISBGN $0, $15, $48, R2, R3
+ LDGR R3, F6
+ WFADB V0, V6, V16
+ MOVD $sinhe4<>+0(SB), R1
+ WFMADB V1, V7, V5, V1
+ WFMDB V4, V16, V4
+ FMOVD 0(R1), F5
+ MOVD $sinhe2<>+0(SB), R1
+ VLEG $0, 0(R1), V16
+ MOVD $sinhe1<>+0(SB), R1
+ WFMADB V2, V5, V16, V5
+ VLEG $0, 0(R1), V16
+ WFMADB V3, V7, V5, V3
+ WFMADB V2, V1, V16, V1
+ FSUB F6, F0
+ FMUL F1, F4
+ MOVD $sinhe0<>+0(SB), R1
+ FMOVD 0(R1), F6
+ WFMADB V2, V3, V6, V2
+ WFMADB V0, V2, V4, V0
+ FMOVD F0, ret+8(FP)
+ RET
+
+L9:
+ WFMADB V0, V1, V6, V0
+ MOVD $sinhx4ff<>+0(SB), R3
+ FMOVD 0(R3), F2
+ FMUL F2, F0
+ WORD $0xA72AF000 //ahi %r2,-4096
+ RISBGN $0, $15, $48, R2, R1
+ LDGR R1, F2
+ FMUL F2, F0
+ FMOVD F0, ret+8(FP)
+ RET
+
+L16:
+ FMOVD F0, ret+8(FP)
+ RET
+
+LEXITTAGsinh:
+sinhIsInf:
+sinhIsZero:
+ FMOVD F0, ret+8(FP)
+ RET
diff --git a/go/src/math/sqrt.go b/go/src/math/sqrt.go
new file mode 100644
index 0000000000000000000000000000000000000000..54929ebcaf74c30fdf6462d521e5aab5fc28942e
--- /dev/null
+++ b/go/src/math/sqrt.go
@@ -0,0 +1,145 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// The original C code and the long comment below are
+// from FreeBSD's /usr/src/lib/msun/src/e_sqrt.c and
+// came with this notice. The go code is a simplified
+// version of the original C.
+//
+// ====================================================
+// Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+//
+// Developed at SunPro, a Sun Microsystems, Inc. business.
+// Permission to use, copy, modify, and distribute this
+// software is freely granted, provided that this notice
+// is preserved.
+// ====================================================
+//
+// __ieee754_sqrt(x)
+// Return correctly rounded sqrt.
+// -----------------------------------------
+// | Use the hardware sqrt if you have one |
+// -----------------------------------------
+// Method:
+// Bit by bit method using integer arithmetic. (Slow, but portable)
+// 1. Normalization
+// Scale x to y in [1,4) with even powers of 2:
+// find an integer k such that 1 <= (y=x*2**(2k)) < 4, then
+// sqrt(x) = 2**k * sqrt(y)
+// 2. Bit by bit computation
+// Let q = sqrt(y) truncated to i bit after binary point (q = 1),
+// i 0
+// i+1 2
+// s = 2*q , and y = 2 * ( y - q ). (1)
+// i i i i
+//
+// To compute q from q , one checks whether
+// i+1 i
+//
+// -(i+1) 2
+// (q + 2 ) <= y. (2)
+// i
+// -(i+1)
+// If (2) is false, then q = q ; otherwise q = q + 2 .
+// i+1 i i+1 i
+//
+// With some algebraic manipulation, it is not difficult to see
+// that (2) is equivalent to
+// -(i+1)
+// s + 2 <= y (3)
+// i i
+//
+// The advantage of (3) is that s and y can be computed by
+// i i
+// the following recurrence formula:
+// if (3) is false
+//
+// s = s , y = y ; (4)
+// i+1 i i+1 i
+//
+// otherwise,
+// -i -(i+1)
+// s = s + 2 , y = y - s - 2 (5)
+// i+1 i i+1 i i
+//
+// One may easily use induction to prove (4) and (5).
+// Note. Since the left hand side of (3) contain only i+2 bits,
+// it is not necessary to do a full (53-bit) comparison
+// in (3).
+// 3. Final rounding
+// After generating the 53 bits result, we compute one more bit.
+// Together with the remainder, we can decide whether the
+// result is exact, bigger than 1/2ulp, or less than 1/2ulp
+// (it will never equal to 1/2ulp).
+// The rounding mode can be detected by checking whether
+// huge + tiny is equal to huge, and whether huge - tiny is
+// equal to huge for some floating point number "huge" and "tiny".
+//
+//
+// Notes: Rounding mode detection omitted. The constants "mask", "shift",
+// and "bias" are found in src/math/bits.go
+
+// Sqrt returns the square root of x.
+//
+// Special cases are:
+//
+// Sqrt(+Inf) = +Inf
+// Sqrt(±0) = ±0
+// Sqrt(x < 0) = NaN
+// Sqrt(NaN) = NaN
+func Sqrt(x float64) float64 {
+ return sqrt(x)
+}
+
+// Note: On systems where Sqrt is a single instruction, the compiler
+// may turn a direct call into a direct use of that instruction instead.
+
+func sqrt(x float64) float64 {
+ // special cases
+ switch {
+ case x == 0 || IsNaN(x) || IsInf(x, 1):
+ return x
+ case x < 0:
+ return NaN()
+ }
+ ix := Float64bits(x)
+ // normalize x
+ exp := int((ix >> shift) & mask)
+ if exp == 0 { // subnormal x
+ for ix&(1<>= 1 // exp = exp/2, exponent of square root
+ // generate sqrt(x) bit by bit
+ ix <<= 1
+ var q, s uint64 // q = sqrt(x)
+ r := uint64(1 << (shift + 1)) // r = moving bit from MSB to LSB
+ for r != 0 {
+ t := s + r
+ if t <= ix {
+ s = t + r
+ ix -= t
+ q += r
+ }
+ ix <<= 1
+ r >>= 1
+ }
+ // final rounding
+ if ix != 0 { // remainder, result not exact
+ q += q & 1 // round according to extra bit
+ }
+ ix = q>>1 + uint64(exp-1+bias)< 2**49 = 5.6e14.
+// [Accuracy loss statement from sin.go comments.]
+//
+// Cephes Math Library Release 2.8: June, 2000
+// Copyright 1984, 1987, 1989, 1992, 2000 by Stephen L. Moshier
+//
+// The readme file at http://netlib.sandia.gov/cephes/ says:
+// Some software in this archive may be from the book _Methods and
+// Programs for Mathematical Functions_ (Prentice-Hall or Simon & Schuster
+// International, 1989) or from the Cephes Mathematical Library, a
+// commercial product. In either event, it is copyrighted by the author.
+// What you see here may be used freely but it comes with no support or
+// guarantee.
+//
+// The two known misprints in the book are repaired here in the
+// source listings for the gamma function and the incomplete beta
+// integral.
+//
+// Stephen L. Moshier
+// moshier@na-net.ornl.gov
+
+// tan coefficients
+var _tanP = [...]float64{
+ -1.30936939181383777646e4, // 0xc0c992d8d24f3f38
+ 1.15351664838587416140e6, // 0x413199eca5fc9ddd
+ -1.79565251976484877988e7, // 0xc1711fead3299176
+}
+var _tanQ = [...]float64{
+ 1.00000000000000000000e0,
+ 1.36812963470692954678e4, // 0x40cab8a5eeb36572
+ -1.32089234440210967447e6, // 0xc13427bc582abc96
+ 2.50083801823357915839e7, // 0x4177d98fc2ead8ef
+ -5.38695755929454629881e7, // 0xc189afe03cbe5a31
+}
+
+// Tan returns the tangent of the radian argument x.
+//
+// Special cases are:
+//
+// Tan(±0) = ±0
+// Tan(±Inf) = NaN
+// Tan(NaN) = NaN
+func Tan(x float64) float64 {
+ if haveArchTan {
+ return archTan(x)
+ }
+ return tan(x)
+}
+
+func tan(x float64) float64 {
+ const (
+ PI4A = 7.85398125648498535156e-1 // 0x3fe921fb40000000, Pi/4 split into three parts
+ PI4B = 3.77489470793079817668e-8 // 0x3e64442d00000000,
+ PI4C = 2.69515142907905952645e-15 // 0x3ce8469898cc5170,
+ )
+ // special cases
+ switch {
+ case x == 0 || IsNaN(x):
+ return x // return ±0 || NaN()
+ case IsInf(x, 0):
+ return NaN()
+ }
+
+ // make argument positive but save the sign
+ sign := false
+ if x < 0 {
+ x = -x
+ sign = true
+ }
+ var j uint64
+ var y, z float64
+ if x >= reduceThreshold {
+ j, z = trigReduce(x)
+ } else {
+ j = uint64(x * (4 / Pi)) // integer part of x/(Pi/4), as integer for tests on the phase angle
+ y = float64(j) // integer part of x/(Pi/4), as float
+
+ /* map zeros and singularities to origin */
+ if j&1 == 1 {
+ j++
+ y++
+ }
+
+ z = ((x - y*PI4A) - y*PI4B) - y*PI4C
+ }
+ zz := z * z
+
+ if zz > 1e-14 {
+ y = z + z*(zz*(((_tanP[0]*zz)+_tanP[1])*zz+_tanP[2])/((((zz+_tanQ[1])*zz+_tanQ[2])*zz+_tanQ[3])*zz+_tanQ[4]))
+ } else {
+ y = z
+ }
+ if j&2 == 2 {
+ y = -1 / y
+ }
+ if sign {
+ y = -y
+ }
+ return y
+}
diff --git a/go/src/math/tan_s390x.s b/go/src/math/tan_s390x.s
new file mode 100644
index 0000000000000000000000000000000000000000..48cd2841e881e00c272640d792bcc25ffa91a574
--- /dev/null
+++ b/go/src/math/tan_s390x.s
@@ -0,0 +1,111 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// Minimax polynomial approximations
+DATA ·tanrodataL13<> + 0(SB)/8, $0.181017336383229927e-07
+DATA ·tanrodataL13<> + 8(SB)/8, $-.256590857271311164e-03
+DATA ·tanrodataL13<> + 16(SB)/8, $-.464359274328689195e+00
+DATA ·tanrodataL13<> + 24(SB)/8, $1.0
+DATA ·tanrodataL13<> + 32(SB)/8, $-.333333333333333464e+00
+DATA ·tanrodataL13<> + 40(SB)/8, $0.245751217306830032e-01
+DATA ·tanrodataL13<> + 48(SB)/8, $-.245391301343844510e-03
+DATA ·tanrodataL13<> + 56(SB)/8, $0.214530914428992319e-01
+DATA ·tanrodataL13<> + 64(SB)/8, $0.108285667160535624e-31
+DATA ·tanrodataL13<> + 72(SB)/8, $0.612323399573676480e-16
+DATA ·tanrodataL13<> + 80(SB)/8, $0.157079632679489656e+01
+DATA ·tanrodataL13<> + 88(SB)/8, $0.636619772367581341e+00
+GLOBL ·tanrodataL13<> + 0(SB), RODATA, $96
+
+// Constants
+DATA ·tanxnan<> + 0(SB)/8, $0x7ff8000000000000
+GLOBL ·tanxnan<> + 0(SB), RODATA, $8
+DATA ·tanxlim<> + 0(SB)/8, $0x432921fb54442d19
+GLOBL ·tanxlim<> + 0(SB), RODATA, $8
+DATA ·tanxadd<> + 0(SB)/8, $0xc338000000000000
+GLOBL ·tanxadd<> + 0(SB), RODATA, $8
+
+// Tan returns the tangent of the radian argument.
+//
+// Special cases are:
+// Tan(±0) = ±0
+// Tan(±Inf) = NaN
+// Tan(NaN) = NaN
+// The algorithm used is minimax polynomial approximation using a table of
+// polynomial coefficients determined with a Remez exchange algorithm.
+
+TEXT ·tanAsm(SB), NOSPLIT, $0-16
+ FMOVD x+0(FP), F0
+ //special case Tan(±0) = ±0
+ FMOVD $(0.0), F1
+ FCMPU F0, F1
+ BEQ atanIsZero
+
+ MOVD $·tanrodataL13<>+0(SB), R5
+ LTDBR F0, F0
+ BLTU L10
+ FMOVD F0, F2
+L2:
+ MOVD $·tanxlim<>+0(SB), R1
+ FMOVD 0(R1), F1
+ FCMPU F2, F1
+ BGT L9
+ BVS L11
+ MOVD $·tanxadd<>+0(SB), R1
+ FMOVD 88(R5), F6
+ FMOVD 0(R1), F4
+ WFMSDB V0, V6, V4, V6
+ FMOVD 80(R5), F1
+ FADD F6, F4
+ FMOVD 72(R5), F2
+ FMSUB F1, F4, F0
+ FMOVD 64(R5), F3
+ WFMADB V4, V2, V0, V2
+ FMOVD 56(R5), F1
+ WFMADB V4, V3, V2, V4
+ FMUL F2, F2
+ VLEG $0, 48(R5), V18
+ LGDR F6, R1
+ FMOVD 40(R5), F5
+ FMOVD 32(R5), F3
+ FMADD F1, F2, F3
+ FMOVD 24(R5), F1
+ FMOVD 16(R5), F7
+ FMOVD 8(R5), F0
+ WFMADB V2, V7, V1, V7
+ WFMADB V2, V0, V5, V0
+ WFMDB V2, V2, V1
+ FMOVD 0(R5), F5
+ WFLCDB V4, V16
+ WFMADB V2, V5, V18, V5
+ WFMADB V1, V0, V7, V0
+ TMLL R1, $1
+ WFMADB V1, V5, V3, V1
+ BNE L12
+ WFDDB V0, V1, V0
+ WFMDB V2, V16, V2
+ WFMADB V2, V0, V4, V0
+ LCDBR F0, F0
+ FMOVD F0, ret+8(FP)
+ RET
+L12:
+ WFMSDB V2, V1, V0, V2
+ WFMDB V16, V2, V2
+ FDIV F2, F0
+ FMOVD F0, ret+8(FP)
+ RET
+L11:
+ MOVD $·tanxnan<>+0(SB), R1
+ FMOVD 0(R1), F0
+ FMOVD F0, ret+8(FP)
+ RET
+L10:
+ LCDBR F0, F2
+ BR L2
+L9:
+ BR ·tan(SB)
+atanIsZero:
+ FMOVD F0, ret+8(FP)
+ RET
diff --git a/go/src/math/tanh.go b/go/src/math/tanh.go
new file mode 100644
index 0000000000000000000000000000000000000000..94ebc3b6515d52cb8eccdc62f341518913c2ec7a
--- /dev/null
+++ b/go/src/math/tanh.go
@@ -0,0 +1,105 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+// The original C code, the long comment, and the constants
+// below were from http://netlib.sandia.gov/cephes/cmath/sin.c,
+// available from http://www.netlib.org/cephes/cmath.tgz.
+// The go code is a simplified version of the original C.
+// tanh.c
+//
+// Hyperbolic tangent
+//
+// SYNOPSIS:
+//
+// double x, y, tanh();
+//
+// y = tanh( x );
+//
+// DESCRIPTION:
+//
+// Returns hyperbolic tangent of argument in the range MINLOG to MAXLOG.
+// MAXLOG = 8.8029691931113054295988e+01 = log(2**127)
+// MINLOG = -8.872283911167299960540e+01 = log(2**-128)
+//
+// A rational function is used for |x| < 0.625. The form
+// x + x**3 P(x)/Q(x) of Cody & Waite is employed.
+// Otherwise,
+// tanh(x) = sinh(x)/cosh(x) = 1 - 2/(exp(2x) + 1).
+//
+// ACCURACY:
+//
+// Relative error:
+// arithmetic domain # trials peak rms
+// IEEE -2,2 30000 2.5e-16 5.8e-17
+//
+// Cephes Math Library Release 2.8: June, 2000
+// Copyright 1984, 1987, 1989, 1992, 2000 by Stephen L. Moshier
+//
+// The readme file at http://netlib.sandia.gov/cephes/ says:
+// Some software in this archive may be from the book _Methods and
+// Programs for Mathematical Functions_ (Prentice-Hall or Simon & Schuster
+// International, 1989) or from the Cephes Mathematical Library, a
+// commercial product. In either event, it is copyrighted by the author.
+// What you see here may be used freely but it comes with no support or
+// guarantee.
+//
+// The two known misprints in the book are repaired here in the
+// source listings for the gamma function and the incomplete beta
+// integral.
+//
+// Stephen L. Moshier
+// moshier@na-net.ornl.gov
+//
+
+var tanhP = [...]float64{
+ -9.64399179425052238628e-1,
+ -9.92877231001918586564e1,
+ -1.61468768441708447952e3,
+}
+var tanhQ = [...]float64{
+ 1.12811678491632931402e2,
+ 2.23548839060100448583e3,
+ 4.84406305325125486048e3,
+}
+
+// Tanh returns the hyperbolic tangent of x.
+//
+// Special cases are:
+//
+// Tanh(±0) = ±0
+// Tanh(±Inf) = ±1
+// Tanh(NaN) = NaN
+func Tanh(x float64) float64 {
+ if haveArchTanh {
+ return archTanh(x)
+ }
+ return tanh(x)
+}
+
+func tanh(x float64) float64 {
+ const MAXLOG = 8.8029691931113054295988e+01 // log(2**127)
+ z := Abs(x)
+ switch {
+ case z > 0.5*MAXLOG:
+ if x < 0 {
+ return -1
+ }
+ return 1
+ case z >= 0.625:
+ s := Exp(2 * z)
+ z = 1 - 2/(s+1)
+ if x < 0 {
+ z = -z
+ }
+ default:
+ if x == 0 {
+ return x
+ }
+ s := x * x
+ z = x + x*s*((tanhP[0]*s+tanhP[1])*s+tanhP[2])/(((s+tanhQ[0])*s+tanhQ[1])*s+tanhQ[2])
+ }
+ return z
+}
diff --git a/go/src/math/tanh_s390x.s b/go/src/math/tanh_s390x.s
new file mode 100644
index 0000000000000000000000000000000000000000..7e2d4dd7972935c305848a407ee6f6c91bdd1b4c
--- /dev/null
+++ b/go/src/math/tanh_s390x.s
@@ -0,0 +1,169 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// Minimax polynomial approximations
+DATA tanhrodataL18<>+0(SB)/8, $-1.0
+DATA tanhrodataL18<>+8(SB)/8, $-2.0
+DATA tanhrodataL18<>+16(SB)/8, $1.0
+DATA tanhrodataL18<>+24(SB)/8, $2.0
+DATA tanhrodataL18<>+32(SB)/8, $0.20000000000000011868E+01
+DATA tanhrodataL18<>+40(SB)/8, $0.13333333333333341256E+01
+DATA tanhrodataL18<>+48(SB)/8, $0.26666666663549111502E+00
+DATA tanhrodataL18<>+56(SB)/8, $0.66666666658721844678E+00
+DATA tanhrodataL18<>+64(SB)/8, $0.88890217768964374821E-01
+DATA tanhrodataL18<>+72(SB)/8, $0.25397199429103821138E-01
+DATA tanhrodataL18<>+80(SB)/8, $-.346573590279972643E+00
+DATA tanhrodataL18<>+88(SB)/8, $20.E0
+GLOBL tanhrodataL18<>+0(SB), RODATA, $96
+
+// Constants
+DATA tanhrlog2<>+0(SB)/8, $0x4007154760000000
+GLOBL tanhrlog2<>+0(SB), RODATA, $8
+DATA tanhxadd<>+0(SB)/8, $0xc2f0000100003ff0
+GLOBL tanhxadd<>+0(SB), RODATA, $8
+DATA tanhxmone<>+0(SB)/8, $-1.0
+GLOBL tanhxmone<>+0(SB), RODATA, $8
+DATA tanhxzero<>+0(SB)/8, $0
+GLOBL tanhxzero<>+0(SB), RODATA, $8
+
+// Polynomial coefficients
+DATA tanhtab<>+0(SB)/8, $0.000000000000000000E+00
+DATA tanhtab<>+8(SB)/8, $-.171540871271399150E-01
+DATA tanhtab<>+16(SB)/8, $-.306597931864376363E-01
+DATA tanhtab<>+24(SB)/8, $-.410200970469965021E-01
+DATA tanhtab<>+32(SB)/8, $-.486343079978231466E-01
+DATA tanhtab<>+40(SB)/8, $-.538226193725835820E-01
+DATA tanhtab<>+48(SB)/8, $-.568439602538111520E-01
+DATA tanhtab<>+56(SB)/8, $-.579091847395528847E-01
+DATA tanhtab<>+64(SB)/8, $-.571909584179366341E-01
+DATA tanhtab<>+72(SB)/8, $-.548312665987204407E-01
+DATA tanhtab<>+80(SB)/8, $-.509471843643441085E-01
+DATA tanhtab<>+88(SB)/8, $-.456353588448863359E-01
+DATA tanhtab<>+96(SB)/8, $-.389755254243262365E-01
+DATA tanhtab<>+104(SB)/8, $-.310332908285244231E-01
+DATA tanhtab<>+112(SB)/8, $-.218623539150173528E-01
+DATA tanhtab<>+120(SB)/8, $-.115062908917949451E-01
+GLOBL tanhtab<>+0(SB), RODATA, $128
+
+// Tanh returns the hyperbolic tangent of the argument.
+//
+// Special cases are:
+// Tanh(±0) = ±0
+// Tanh(±Inf) = ±1
+// Tanh(NaN) = NaN
+// The algorithm used is minimax polynomial approximation using a table of
+// polynomial coefficients determined with a Remez exchange algorithm.
+
+TEXT ·tanhAsm(SB),NOSPLIT,$0-16
+ FMOVD x+0(FP), F0
+ // special case Tanh(±0) = ±0
+ FMOVD $(0.0), F1
+ FCMPU F0, F1
+ BEQ tanhIsZero
+ MOVD $tanhrodataL18<>+0(SB), R5
+ LTDBR F0, F0
+ MOVD $0x4034000000000000, R1
+ BLTU L15
+ FMOVD F0, F1
+L2:
+ MOVD $tanhxadd<>+0(SB), R2
+ FMOVD 0(R2), F2
+ MOVD tanhrlog2<>+0(SB), R2
+ LDGR R2, F4
+ WFMSDB V0, V4, V2, V4
+ MOVD $tanhtab<>+0(SB), R3
+ LGDR F4, R2
+ RISBGZ $57, $60, $3, R2, R4
+ WORD $0xED105058 //cdb %f1,.L19-.L18(%r5)
+ BYTE $0x00
+ BYTE $0x19
+ RISBGN $0, $15, $48, R2, R1
+ WORD $0x68543000 //ld %f5,0(%r4,%r3)
+ LDGR R1, F6
+ BLT L3
+ MOVD $tanhxzero<>+0(SB), R1
+ FMOVD 0(R1), F2
+ WFCHDBS V0, V2, V4
+ BEQ L9
+ WFCHDBS V2, V0, V2
+ BNE L1
+ MOVD $tanhxmone<>+0(SB), R1
+ FMOVD 0(R1), F0
+ FMOVD F0, ret+8(FP)
+ RET
+
+L3:
+ FADD F4, F2
+ FMOVD tanhrodataL18<>+80(SB), F4
+ FMADD F4, F2, F0
+ FMOVD tanhrodataL18<>+72(SB), F1
+ WFMDB V0, V0, V3
+ FMOVD tanhrodataL18<>+64(SB), F2
+ WFMADB V0, V1, V2, V1
+ FMOVD tanhrodataL18<>+56(SB), F4
+ FMOVD tanhrodataL18<>+48(SB), F2
+ WFMADB V1, V3, V4, V1
+ FMOVD tanhrodataL18<>+40(SB), F4
+ WFMADB V3, V2, V4, V2
+ FMOVD tanhrodataL18<>+32(SB), F4
+ WORD $0xB9270022 //lhr %r2,%r2
+ WFMADB V3, V1, V4, V1
+ FMOVD tanhrodataL18<>+24(SB), F4
+ WFMADB V3, V2, V4, V3
+ WFMADB V0, V5, V0, V2
+ WFMADB V0, V1, V3, V0
+ WORD $0xA7183ECF //lhi %r1,16079
+ WFMADB V0, V2, V5, V2
+ FMUL F6, F2
+ MOVW R2, R10
+ MOVW R1, R11
+ CMPBLE R10, R11, L16
+ FMOVD F6, F0
+ WORD $0xED005010 //adb %f0,.L28-.L18(%r5)
+ BYTE $0x00
+ BYTE $0x1A
+ WORD $0xA7184330 //lhi %r1,17200
+ FADD F2, F0
+ MOVW R2, R10
+ MOVW R1, R11
+ CMPBGT R10, R11, L17
+ WORD $0xED605010 //sdb %f6,.L28-.L18(%r5)
+ BYTE $0x00
+ BYTE $0x1B
+ FADD F6, F2
+ WFDDB V0, V2, V0
+ FMOVD F0, ret+8(FP)
+ RET
+
+L9:
+ FMOVD tanhrodataL18<>+16(SB), F0
+L1:
+ FMOVD F0, ret+8(FP)
+ RET
+
+L15:
+ FNEG F0, F1
+ BR L2
+L16:
+ FADD F6, F2
+ FMOVD tanhrodataL18<>+8(SB), F0
+ FMADD F4, F2, F0
+ FMOVD tanhrodataL18<>+0(SB), F4
+ FNEG F0, F0
+ WFMADB V0, V2, V4, V0
+ FMOVD F0, ret+8(FP)
+ RET
+
+L17:
+ WFDDB V0, V4, V0
+ FMOVD tanhrodataL18<>+16(SB), F2
+ WFSDB V0, V2, V0
+ FMOVD F0, ret+8(FP)
+ RET
+
+tanhIsZero: //return ±0
+ FMOVD F0, ret+8(FP)
+ RET
diff --git a/go/src/math/trig_reduce.go b/go/src/math/trig_reduce.go
new file mode 100644
index 0000000000000000000000000000000000000000..5ecdd8375e3295b5aa3f9bc60f0ab40b06db9f54
--- /dev/null
+++ b/go/src/math/trig_reduce.go
@@ -0,0 +1,102 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+import (
+ "math/bits"
+)
+
+// reduceThreshold is the maximum value of x where the reduction using Pi/4
+// in 3 float64 parts still gives accurate results. This threshold
+// is set by y*C being representable as a float64 without error
+// where y is given by y = floor(x * (4 / Pi)) and C is the leading partial
+// terms of 4/Pi. Since the leading terms (PI4A and PI4B in sin.go) have 30
+// and 32 trailing zero bits, y should have less than 30 significant bits.
+//
+// y < 1<<30 -> floor(x*4/Pi) < 1<<30 -> x < (1<<30 - 1) * Pi/4
+//
+// So, conservatively we can take x < 1<<29.
+// Above this threshold Payne-Hanek range reduction must be used.
+const reduceThreshold = 1 << 29
+
+// trigReduce implements Payne-Hanek range reduction by Pi/4
+// for x > 0. It returns the integer part mod 8 (j) and
+// the fractional part (z) of x / (Pi/4).
+// The implementation is based on:
+// "ARGUMENT REDUCTION FOR HUGE ARGUMENTS: Good to the Last Bit"
+// K. C. Ng et al, March 24, 1992
+// The simulated multi-precision calculation of x*B uses 64-bit integer arithmetic.
+func trigReduce(x float64) (j uint64, z float64) {
+ const PI4 = Pi / 4
+ if x < PI4 {
+ return 0, x
+ }
+ // Extract out the integer and exponent such that,
+ // x = ix * 2 ** exp.
+ ix := Float64bits(x)
+ exp := int(ix>>shift&mask) - bias - shift
+ ix &^= mask << shift
+ ix |= 1 << shift
+ // Use the exponent to extract the 3 appropriate uint64 digits from mPi4,
+ // B ~ (z0, z1, z2), such that the product leading digit has the exponent -61.
+ // Note, exp >= -53 since x >= PI4 and exp < 971 for maximum float64.
+ digit, bitshift := uint(exp+61)/64, uint(exp+61)%64
+ z0 := (mPi4[digit] << bitshift) | (mPi4[digit+1] >> (64 - bitshift))
+ z1 := (mPi4[digit+1] << bitshift) | (mPi4[digit+2] >> (64 - bitshift))
+ z2 := (mPi4[digit+2] << bitshift) | (mPi4[digit+3] >> (64 - bitshift))
+ // Multiply mantissa by the digits and extract the upper two digits (hi, lo).
+ z2hi, _ := bits.Mul64(z2, ix)
+ z1hi, z1lo := bits.Mul64(z1, ix)
+ z0lo := z0 * ix
+ lo, c := bits.Add64(z1lo, z2hi, 0)
+ hi, _ := bits.Add64(z0lo, z1hi, c)
+ // The top 3 bits are j.
+ j = hi >> 61
+ // Extract the fraction and find its magnitude.
+ hi = hi<<3 | lo>>61
+ lz := uint(bits.LeadingZeros64(hi))
+ e := uint64(bias - (lz + 1))
+ // Clear implicit mantissa bit and shift into place.
+ hi = (hi << (lz + 1)) | (lo >> (64 - (lz + 1)))
+ hi >>= 64 - shift
+ // Include the exponent and convert to a float.
+ hi |= e << shift
+ z = Float64frombits(hi)
+ // Map zeros to origin.
+ if j&1 == 1 {
+ j++
+ j &= 7
+ z--
+ }
+ // Multiply the fractional part by pi/4.
+ return j, z * PI4
+}
+
+// mPi4 is the binary digits of 4/pi as a uint64 array,
+// that is, 4/pi = Sum mPi4[i]*2^(-64*i)
+// 19 64-bit digits and the leading one bit give 1217 bits
+// of precision to handle the largest possible float64 exponent.
+var mPi4 = [...]uint64{
+ 0x0000000000000001,
+ 0x45f306dc9c882a53,
+ 0xf84eafa3ea69bb81,
+ 0xb6c52b3278872083,
+ 0xfca2c757bd778ac3,
+ 0x6e48dc74849ba5c0,
+ 0x0c925dd413a32439,
+ 0xfc3bd63962534e7d,
+ 0xd1046bea5d768909,
+ 0xd338e04d68befc82,
+ 0x7323ac7306a673e9,
+ 0x3908bf177bf25076,
+ 0x3ff12fffbc0b301f,
+ 0xde5e2316b414da3e,
+ 0xda6cfd9e4f96136e,
+ 0x9e8c7ecd3cbfd45a,
+ 0xea4f758fd7cbe2f6,
+ 0x7a0e73ef14a525d4,
+ 0xd7f6bf623f1aba10,
+ 0xac06608df8f6d757,
+}
diff --git a/go/src/math/unsafe.go b/go/src/math/unsafe.go
new file mode 100644
index 0000000000000000000000000000000000000000..e251f62a2a138508484a76e6dd66f3d8675efe3f
--- /dev/null
+++ b/go/src/math/unsafe.go
@@ -0,0 +1,41 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package math
+
+import "unsafe"
+
+// Despite being an exported symbol,
+// Float32bits is linknamed by widely used packages.
+// Notable members of the hall of shame include:
+// - gitee.com/quant1x/num
+//
+// Do not remove or change the type signature.
+// See go.dev/issue/67401.
+//
+// Note that this comment is not part of the doc comment.
+//
+//go:linkname Float32bits
+
+// Float32bits returns the IEEE 754 binary representation of f,
+// with the sign bit of f and the result in the same bit position.
+// Float32bits(Float32frombits(x)) == x.
+func Float32bits(f float32) uint32 { return *(*uint32)(unsafe.Pointer(&f)) }
+
+// Float32frombits returns the floating-point number corresponding
+// to the IEEE 754 binary representation b, with the sign bit of b
+// and the result in the same bit position.
+// Float32frombits(Float32bits(x)) == x.
+func Float32frombits(b uint32) float32 { return *(*float32)(unsafe.Pointer(&b)) }
+
+// Float64bits returns the IEEE 754 binary representation of f,
+// with the sign bit of f and the result in the same bit position,
+// and Float64bits(Float64frombits(x)) == x.
+func Float64bits(f float64) uint64 { return *(*uint64)(unsafe.Pointer(&f)) }
+
+// Float64frombits returns the floating-point number corresponding
+// to the IEEE 754 binary representation b, with the sign bit of b
+// and the result in the same bit position.
+// Float64frombits(Float64bits(x)) == x.
+func Float64frombits(b uint64) float64 { return *(*float64)(unsafe.Pointer(&b)) }
diff --git a/go/src/mime/encodedword.go b/go/src/mime/encodedword.go
new file mode 100644
index 0000000000000000000000000000000000000000..c4afad043a290837ef51e5d177e96e7b843e071a
--- /dev/null
+++ b/go/src/mime/encodedword.go
@@ -0,0 +1,414 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mime
+
+import (
+ "bytes"
+ "encoding/base64"
+ "errors"
+ "fmt"
+ "io"
+ "strings"
+ "unicode"
+ "unicode/utf8"
+)
+
+// A WordEncoder is an RFC 2047 encoded-word encoder.
+type WordEncoder byte
+
+const (
+ // BEncoding represents Base64 encoding scheme as defined by RFC 2045.
+ BEncoding = WordEncoder('b')
+ // QEncoding represents the Q-encoding scheme as defined by RFC 2047.
+ QEncoding = WordEncoder('q')
+)
+
+var (
+ errInvalidWord = errors.New("mime: invalid RFC 2047 encoded-word")
+)
+
+// Encode returns the encoded-word form of s. If s is ASCII without special
+// characters, it is returned unchanged. The provided charset is the IANA
+// charset name of s. It is case insensitive.
+func (e WordEncoder) Encode(charset, s string) string {
+ if !needsEncoding(s) {
+ return s
+ }
+ return e.encodeWord(charset, s)
+}
+
+func needsEncoding(s string) bool {
+ for _, b := range s {
+ if (b < ' ' || b > '~') && b != '\t' {
+ return true
+ }
+ }
+ return false
+}
+
+// encodeWord encodes a string into an encoded-word.
+func (e WordEncoder) encodeWord(charset, s string) string {
+ var buf strings.Builder
+ // Could use a hint like len(s)*3, but that's not enough for cases
+ // with word splits and too much for simpler inputs.
+ // 48 is close to maxEncodedWordLen/2, but adjusted to allocator size class.
+ buf.Grow(48)
+
+ e.openWord(&buf, charset)
+ if e == BEncoding {
+ e.bEncode(&buf, charset, s)
+ } else {
+ e.qEncode(&buf, charset, s)
+ }
+ closeWord(&buf)
+
+ return buf.String()
+}
+
+const (
+ // The maximum length of an encoded-word is 75 characters.
+ // See RFC 2047, section 2.
+ maxEncodedWordLen = 75
+ // maxContentLen is how much content can be encoded, ignoring the header and
+ // 2-byte footer.
+ maxContentLen = maxEncodedWordLen - len("=?UTF-8?q?") - len("?=")
+)
+
+var maxBase64Len = base64.StdEncoding.DecodedLen(maxContentLen)
+
+// bEncode encodes s using base64 encoding and writes it to buf.
+func (e WordEncoder) bEncode(buf *strings.Builder, charset, s string) {
+ w := base64.NewEncoder(base64.StdEncoding, buf)
+ // If the charset is not UTF-8 or if the content is short, do not bother
+ // splitting the encoded-word.
+ if !isUTF8(charset) || base64.StdEncoding.EncodedLen(len(s)) <= maxContentLen {
+ io.WriteString(w, s)
+ w.Close()
+ return
+ }
+
+ var currentLen, last, runeLen int
+ for i := 0; i < len(s); i += runeLen {
+ // Multi-byte characters must not be split across encoded-words.
+ // See RFC 2047, section 5.3.
+ _, runeLen = utf8.DecodeRuneInString(s[i:])
+
+ if currentLen+runeLen <= maxBase64Len {
+ currentLen += runeLen
+ } else {
+ io.WriteString(w, s[last:i])
+ w.Close()
+ e.splitWord(buf, charset)
+ last = i
+ currentLen = runeLen
+ }
+ }
+ io.WriteString(w, s[last:])
+ w.Close()
+}
+
+// qEncode encodes s using Q encoding and writes it to buf. It splits the
+// encoded-words when necessary.
+func (e WordEncoder) qEncode(buf *strings.Builder, charset, s string) {
+ // We only split encoded-words when the charset is UTF-8.
+ if !isUTF8(charset) {
+ writeQString(buf, s)
+ return
+ }
+
+ var currentLen, runeLen int
+ for i := 0; i < len(s); i += runeLen {
+ b := s[i]
+ // Multi-byte characters must not be split across encoded-words.
+ // See RFC 2047, section 5.3.
+ var encLen int
+ if b >= ' ' && b <= '~' && b != '=' && b != '?' && b != '_' {
+ runeLen, encLen = 1, 1
+ } else {
+ _, runeLen = utf8.DecodeRuneInString(s[i:])
+ encLen = 3 * runeLen
+ }
+
+ if currentLen+encLen > maxContentLen {
+ e.splitWord(buf, charset)
+ currentLen = 0
+ }
+ writeQString(buf, s[i:i+runeLen])
+ currentLen += encLen
+ }
+}
+
+// writeQString encodes s using Q encoding and writes it to buf.
+func writeQString(buf *strings.Builder, s string) {
+ for i := 0; i < len(s); i++ {
+ switch b := s[i]; {
+ case b == ' ':
+ buf.WriteByte('_')
+ case b >= '!' && b <= '~' && b != '=' && b != '?' && b != '_':
+ buf.WriteByte(b)
+ default:
+ buf.WriteByte('=')
+ buf.WriteByte(upperhex[b>>4])
+ buf.WriteByte(upperhex[b&0x0f])
+ }
+ }
+}
+
+// openWord writes the beginning of an encoded-word into buf.
+func (e WordEncoder) openWord(buf *strings.Builder, charset string) {
+ buf.WriteString("=?")
+ buf.WriteString(charset)
+ buf.WriteByte('?')
+ buf.WriteByte(byte(e))
+ buf.WriteByte('?')
+}
+
+// closeWord writes the end of an encoded-word into buf.
+func closeWord(buf *strings.Builder) {
+ buf.WriteString("?=")
+}
+
+// splitWord closes the current encoded-word and opens a new one.
+func (e WordEncoder) splitWord(buf *strings.Builder, charset string) {
+ closeWord(buf)
+ buf.WriteByte(' ')
+ e.openWord(buf, charset)
+}
+
+func isUTF8(charset string) bool {
+ return strings.EqualFold(charset, "UTF-8")
+}
+
+const upperhex = "0123456789ABCDEF"
+
+// A WordDecoder decodes MIME headers containing RFC 2047 encoded-words.
+type WordDecoder struct {
+ // CharsetReader, if non-nil, defines a function to generate
+ // charset-conversion readers, converting from the provided
+ // charset into UTF-8.
+ // Charsets are always lower-case. utf-8, iso-8859-1 and us-ascii charsets
+ // are handled by default.
+ // One of the CharsetReader's result values must be non-nil.
+ CharsetReader func(charset string, input io.Reader) (io.Reader, error)
+}
+
+// Decode decodes an RFC 2047 encoded-word.
+func (d *WordDecoder) Decode(word string) (string, error) {
+ // See https://tools.ietf.org/html/rfc2047#section-2 for details.
+ // Our decoder is permissive, we accept empty encoded-text.
+ if len(word) < 8 || !strings.HasPrefix(word, "=?") || !strings.HasSuffix(word, "?=") || strings.Count(word, "?") != 4 {
+ return "", errInvalidWord
+ }
+ word = word[2 : len(word)-2]
+
+ // split word "UTF-8?q?text" into "UTF-8", 'q', and "text"
+ charset, text, _ := strings.Cut(word, "?")
+ if charset == "" {
+ return "", errInvalidWord
+ }
+ encoding, text, _ := strings.Cut(text, "?")
+ if len(encoding) != 1 {
+ return "", errInvalidWord
+ }
+
+ content, err := decode(encoding[0], text)
+ if err != nil {
+ return "", err
+ }
+
+ var buf strings.Builder
+ if err := d.convert(&buf, charset, content); err != nil {
+ return "", err
+ }
+ return buf.String(), nil
+}
+
+// DecodeHeader decodes all encoded-words of the given string. It returns an
+// error if and only if [WordDecoder.CharsetReader] of d returns an error.
+func (d *WordDecoder) DecodeHeader(header string) (string, error) {
+ // If there is no encoded-word, returns before creating a buffer.
+ i := strings.Index(header, "=?")
+ if i == -1 {
+ return header, nil
+ }
+
+ var buf strings.Builder
+
+ buf.WriteString(header[:i])
+ header = header[i:]
+
+ betweenWords := false
+ for {
+ start := strings.Index(header, "=?")
+ if start == -1 {
+ break
+ }
+ cur := start + len("=?")
+
+ i := strings.Index(header[cur:], "?")
+ if i == -1 {
+ break
+ }
+ charset := header[cur : cur+i]
+ cur += i + len("?")
+
+ if len(header) < cur+len("Q??=") {
+ break
+ }
+ encoding := header[cur]
+ cur++
+
+ if header[cur] != '?' {
+ break
+ }
+ cur++
+
+ j := strings.Index(header[cur:], "?=")
+ if j == -1 {
+ break
+ }
+ text := header[cur : cur+j]
+ end := cur + j + len("?=")
+
+ content, err := decode(encoding, text)
+ if err != nil {
+ betweenWords = false
+ buf.WriteString(header[:start+2])
+ header = header[start+2:]
+ continue
+ }
+
+ // Write characters before the encoded-word. White-space and newline
+ // characters separating two encoded-words must be deleted.
+ if start > 0 && (!betweenWords || hasNonWhitespace(header[:start])) {
+ buf.WriteString(header[:start])
+ }
+
+ if err := d.convert(&buf, charset, content); err != nil {
+ return "", err
+ }
+
+ header = header[end:]
+ betweenWords = true
+ }
+
+ if len(header) > 0 {
+ buf.WriteString(header)
+ }
+
+ return buf.String(), nil
+}
+
+func decode(encoding byte, text string) ([]byte, error) {
+ switch encoding {
+ case 'B', 'b':
+ return base64.StdEncoding.DecodeString(text)
+ case 'Q', 'q':
+ return qDecode(text)
+ default:
+ return nil, errInvalidWord
+ }
+}
+
+func (d *WordDecoder) convert(buf *strings.Builder, charset string, content []byte) error {
+ switch {
+ case strings.EqualFold("utf-8", charset):
+ buf.Write(content)
+ case strings.EqualFold("iso-8859-1", charset):
+ for _, c := range content {
+ buf.WriteRune(rune(c))
+ }
+ case strings.EqualFold("us-ascii", charset):
+ for _, c := range content {
+ if c >= utf8.RuneSelf {
+ buf.WriteRune(unicode.ReplacementChar)
+ } else {
+ buf.WriteByte(c)
+ }
+ }
+ default:
+ if d.CharsetReader == nil {
+ return fmt.Errorf("mime: unhandled charset %q", charset)
+ }
+ r, err := d.CharsetReader(strings.ToLower(charset), bytes.NewReader(content))
+ if err != nil {
+ return err
+ }
+ if _, err = io.Copy(buf, r); err != nil {
+ return err
+ }
+ }
+ return nil
+}
+
+// hasNonWhitespace reports whether s (assumed to be ASCII) contains at least
+// one byte of non-whitespace.
+func hasNonWhitespace(s string) bool {
+ for _, b := range s {
+ switch b {
+ // Encoded-words can only be separated by linear white spaces which does
+ // not include vertical tabs (\v).
+ case ' ', '\t', '\n', '\r':
+ default:
+ return true
+ }
+ }
+ return false
+}
+
+// qDecode decodes a Q encoded string.
+func qDecode(s string) ([]byte, error) {
+ dec := make([]byte, len(s))
+ n := 0
+ for i := 0; i < len(s); i++ {
+ switch c := s[i]; {
+ case c == '_':
+ dec[n] = ' '
+ case c == '=':
+ if i+2 >= len(s) {
+ return nil, errInvalidWord
+ }
+ b, err := readHexByte(s[i+1], s[i+2])
+ if err != nil {
+ return nil, err
+ }
+ dec[n] = b
+ i += 2
+ case (c <= '~' && c >= ' ') || c == '\n' || c == '\r' || c == '\t':
+ dec[n] = c
+ default:
+ return nil, errInvalidWord
+ }
+ n++
+ }
+
+ return dec[:n], nil
+}
+
+// readHexByte returns the byte from its quoted-printable representation.
+func readHexByte(a, b byte) (byte, error) {
+ var hb, lb byte
+ var err error
+ if hb, err = fromHex(a); err != nil {
+ return 0, err
+ }
+ if lb, err = fromHex(b); err != nil {
+ return 0, err
+ }
+ return hb<<4 | lb, nil
+}
+
+func fromHex(b byte) (byte, error) {
+ switch {
+ case b >= '0' && b <= '9':
+ return b - '0', nil
+ case b >= 'A' && b <= 'F':
+ return b - 'A' + 10, nil
+ // Accept badly encoded bytes.
+ case b >= 'a' && b <= 'f':
+ return b - 'a' + 10, nil
+ }
+ return 0, fmt.Errorf("mime: invalid hex byte %#02x", b)
+}
diff --git a/go/src/mime/encodedword_test.go b/go/src/mime/encodedword_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..2a98794380fb029bb61b51d59a9de8eb67d81cf6
--- /dev/null
+++ b/go/src/mime/encodedword_test.go
@@ -0,0 +1,239 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mime
+
+import (
+ "errors"
+ "io"
+ "strings"
+ "testing"
+)
+
+func TestEncodeWord(t *testing.T) {
+ utf8, iso88591 := "utf-8", "iso-8859-1"
+ tests := []struct {
+ enc WordEncoder
+ charset string
+ src, exp string
+ }{
+ {QEncoding, utf8, "François-Jérôme", "=?utf-8?q?Fran=C3=A7ois-J=C3=A9r=C3=B4me?="},
+ {BEncoding, utf8, "Café", "=?utf-8?b?Q2Fmw6k=?="},
+ {QEncoding, iso88591, "La Seleção", "=?iso-8859-1?q?La_Sele=C3=A7=C3=A3o?="},
+ {QEncoding, utf8, "", ""},
+ {QEncoding, utf8, "A", "A"},
+ {QEncoding, iso88591, "a", "a"},
+ {QEncoding, utf8, "123 456", "123 456"},
+ {QEncoding, utf8, "\t !\"#$%&'()*+,-./ :;<>?@[\\]^_`{|}~", "\t !\"#$%&'()*+,-./ :;<>?@[\\]^_`{|}~"},
+ {QEncoding, utf8, strings.Repeat("é", 10), "=?utf-8?q?" + strings.Repeat("=C3=A9", 10) + "?="},
+ {QEncoding, utf8, strings.Repeat("é", 11), "=?utf-8?q?" + strings.Repeat("=C3=A9", 10) + "?= =?utf-8?q?=C3=A9?="},
+ {QEncoding, iso88591, strings.Repeat("\xe9", 22), "=?iso-8859-1?q?" + strings.Repeat("=E9", 22) + "?="},
+ {QEncoding, utf8, strings.Repeat("\x80", 22), "=?utf-8?q?" + strings.Repeat("=80", 21) + "?= =?utf-8?q?=80?="},
+ {BEncoding, iso88591, strings.Repeat("\xe9", 45), "=?iso-8859-1?b?" + strings.Repeat("6enp", 15) + "?="},
+ {BEncoding, utf8, strings.Repeat("\x80", 48), "=?utf-8?b?" + strings.Repeat("gICA", 15) + "?= =?utf-8?b?gICA?="},
+ }
+
+ for _, test := range tests {
+ if s := test.enc.Encode(test.charset, test.src); s != test.exp {
+ t.Errorf("Encode(%q) = %q, want %q", test.src, s, test.exp)
+ }
+ }
+}
+
+func TestEncodedWordLength(t *testing.T) {
+ tests := []struct {
+ enc WordEncoder
+ src string
+ }{
+ {QEncoding, strings.Repeat("à", 30)},
+ {QEncoding, strings.Repeat("é", 60)},
+ {BEncoding, strings.Repeat("ï", 25)},
+ {BEncoding, strings.Repeat("ô", 37)},
+ {BEncoding, strings.Repeat("\x80", 50)},
+ {QEncoding, "{$firstname} Bienvendio a Apostolica, aquà inicia el camino de tu"},
+ }
+
+ for _, test := range tests {
+ s := test.enc.Encode("utf-8", test.src)
+ wordLen := 0
+ for i := 0; i < len(s); i++ {
+ if s[i] == ' ' {
+ wordLen = 0
+ continue
+ }
+
+ wordLen++
+ if wordLen > maxEncodedWordLen {
+ t.Errorf("Encode(%q) has more than %d characters: %q",
+ test.src, maxEncodedWordLen, s)
+ }
+ }
+ }
+}
+
+func TestDecodeWord(t *testing.T) {
+ tests := []struct {
+ src, exp string
+ hasErr bool
+ }{
+ {"=?UTF-8?Q?=C2=A1Hola,_se=C3=B1or!?=", "¡Hola, señor!", false},
+ {"=?UTF-8?Q?Fran=C3=A7ois-J=C3=A9r=C3=B4me?=", "François-Jérôme", false},
+ {"=?UTF-8?q?ascii?=", "ascii", false},
+ {"=?utf-8?B?QW5kcsOp?=", "André", false},
+ {"=?ISO-8859-1?Q?Rapha=EBl_Dupont?=", "Raphaël Dupont", false},
+ {"=?utf-8?b?IkFudG9uaW8gSm9zw6kiIDxqb3NlQGV4YW1wbGUub3JnPg==?=", `"Antonio José" `, false},
+ {"=?UTF-8?A?Test?=", "", true},
+ {"=?UTF-8?Q?A=B?=", "", true},
+ {"=?UTF-8?Q?=A?=", "", true},
+ {"=?UTF-8?A?A?=", "", true},
+ {"=????=", "", true},
+ {"=?UTF-8???=", "", true},
+ {"=?UTF-8?Q??=", "", false},
+ }
+
+ for _, test := range tests {
+ dec := new(WordDecoder)
+ s, err := dec.Decode(test.src)
+ if test.hasErr && err == nil {
+ t.Errorf("Decode(%q) should return an error", test.src)
+ continue
+ }
+ if !test.hasErr && err != nil {
+ t.Errorf("Decode(%q): %v", test.src, err)
+ continue
+ }
+ if s != test.exp {
+ t.Errorf("Decode(%q) = %q, want %q", test.src, s, test.exp)
+ }
+ }
+}
+
+func TestDecodeHeader(t *testing.T) {
+ tests := []struct {
+ src, exp string
+ }{
+ {"=?UTF-8?Q?=C2=A1Hola,_se=C3=B1or!?=", "¡Hola, señor!"},
+ {"=?UTF-8?Q?Fran=C3=A7ois-J=C3=A9r=C3=B4me?=", "François-Jérôme"},
+ {"=?UTF-8?q?ascii?=", "ascii"},
+ {"=?utf-8?B?QW5kcsOp?=", "André"},
+ {"=?ISO-8859-1?Q?Rapha=EBl_Dupont?=", "Raphaël Dupont"},
+ {"Jean", "Jean"},
+ {"=?utf-8?b?IkFudG9uaW8gSm9zw6kiIDxqb3NlQGV4YW1wbGUub3JnPg==?=", `"Antonio José" `},
+ {"=?UTF-8?A?Test?=", "=?UTF-8?A?Test?="},
+ {"=?UTF-8?Q?A=B?=", "=?UTF-8?Q?A=B?="},
+ {"=?UTF-8?Q?=A?=", "=?UTF-8?Q?=A?="},
+ {"=?UTF-8?A?A?=", "=?UTF-8?A?A?="},
+ // Incomplete words
+ {"=?", "=?"},
+ {"=?UTF-8?", "=?UTF-8?"},
+ {"=?UTF-8?=", "=?UTF-8?="},
+ {"=?UTF-8?Q", "=?UTF-8?Q"},
+ {"=?UTF-8?Q?", "=?UTF-8?Q?"},
+ {"=?UTF-8?Q?=", "=?UTF-8?Q?="},
+ {"=?UTF-8?Q?A", "=?UTF-8?Q?A"},
+ {"=?UTF-8?Q?A?", "=?UTF-8?Q?A?"},
+ // Tests from RFC 2047
+ {"=?ISO-8859-1?Q?a?=", "a"},
+ {"=?ISO-8859-1?Q?a?= b", "a b"},
+ {"=?ISO-8859-1?Q?a?= =?ISO-8859-1?Q?b?=", "ab"},
+ {"=?ISO-8859-1?Q?a?= =?ISO-8859-1?Q?b?=", "ab"},
+ {"=?ISO-8859-1?Q?a?= \r\n\t =?ISO-8859-1?Q?b?=", "ab"},
+ {"=?ISO-8859-1?Q?a_b?=", "a b"},
+ }
+
+ for _, test := range tests {
+ dec := new(WordDecoder)
+ s, err := dec.DecodeHeader(test.src)
+ if err != nil {
+ t.Errorf("DecodeHeader(%q): %v", test.src, err)
+ }
+ if s != test.exp {
+ t.Errorf("DecodeHeader(%q) = %q, want %q", test.src, s, test.exp)
+ }
+ }
+}
+
+func TestCharsetDecoder(t *testing.T) {
+ tests := []struct {
+ src string
+ want string
+ charsets []string
+ content []string
+ }{
+ {"=?utf-8?b?Q2Fmw6k=?=", "Café", nil, nil},
+ {"=?ISO-8859-1?Q?caf=E9?=", "café", nil, nil},
+ {"=?US-ASCII?Q?foo_bar?=", "foo bar", nil, nil},
+ {"=?utf-8?Q?=?=", "=?utf-8?Q?=?=", nil, nil},
+ {"=?utf-8?Q?=A?=", "=?utf-8?Q?=A?=", nil, nil},
+ {
+ "=?ISO-8859-15?Q?f=F5=F6?= =?windows-1252?Q?b=E0r?=",
+ "f\xf5\xf6b\xe0r",
+ []string{"iso-8859-15", "windows-1252"},
+ []string{"f\xf5\xf6", "b\xe0r"},
+ },
+ }
+
+ for _, test := range tests {
+ i := 0
+ dec := &WordDecoder{
+ CharsetReader: func(charset string, input io.Reader) (io.Reader, error) {
+ if charset != test.charsets[i] {
+ t.Errorf("DecodeHeader(%q), got charset %q, want %q", test.src, charset, test.charsets[i])
+ }
+ content, err := io.ReadAll(input)
+ if err != nil {
+ t.Errorf("DecodeHeader(%q), error in reader: %v", test.src, err)
+ }
+ got := string(content)
+ if got != test.content[i] {
+ t.Errorf("DecodeHeader(%q), got content %q, want %q", test.src, got, test.content[i])
+ }
+ i++
+
+ return strings.NewReader(got), nil
+ },
+ }
+ got, err := dec.DecodeHeader(test.src)
+ if err != nil {
+ t.Errorf("DecodeHeader(%q): %v", test.src, err)
+ }
+ if got != test.want {
+ t.Errorf("DecodeHeader(%q) = %q, want %q", test.src, got, test.want)
+ }
+ }
+}
+
+func TestCharsetDecoderError(t *testing.T) {
+ dec := &WordDecoder{
+ CharsetReader: func(charset string, input io.Reader) (io.Reader, error) {
+ return nil, errors.New("Test error")
+ },
+ }
+
+ if _, err := dec.DecodeHeader("=?charset?Q?foo?="); err == nil {
+ t.Error("DecodeHeader should return an error")
+ }
+}
+
+func BenchmarkQEncodeWord(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ QEncoding.Encode("UTF-8", "¡Hola, señor!")
+ }
+}
+
+func BenchmarkQDecodeWord(b *testing.B) {
+ dec := new(WordDecoder)
+
+ for i := 0; i < b.N; i++ {
+ dec.Decode("=?utf-8?q?=C2=A1Hola,_se=C3=B1or!?=")
+ }
+}
+
+func BenchmarkQDecodeHeader(b *testing.B) {
+ dec := new(WordDecoder)
+
+ for i := 0; i < b.N; i++ {
+ dec.DecodeHeader("=?utf-8?q?=C2=A1Hola,_se=C3=B1or!?=")
+ }
+}
diff --git a/go/src/mime/example_test.go b/go/src/mime/example_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..8a96873e5dc6b77d34f69563e8fea4f9e40b6743
--- /dev/null
+++ b/go/src/mime/example_test.go
@@ -0,0 +1,123 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mime_test
+
+import (
+ "bytes"
+ "fmt"
+ "io"
+ "mime"
+)
+
+func ExampleWordEncoder_Encode() {
+ fmt.Println(mime.QEncoding.Encode("utf-8", "¡Hola, señor!"))
+ fmt.Println(mime.QEncoding.Encode("utf-8", "Hello!"))
+ fmt.Println(mime.BEncoding.Encode("UTF-8", "¡Hola, señor!"))
+ fmt.Println(mime.QEncoding.Encode("ISO-8859-1", "Caf\xE9"))
+ // Output:
+ // =?utf-8?q?=C2=A1Hola,_se=C3=B1or!?=
+ // Hello!
+ // =?UTF-8?b?wqFIb2xhLCBzZcOxb3Ih?=
+ // =?ISO-8859-1?q?Caf=E9?=
+}
+
+func ExampleWordDecoder_Decode() {
+ dec := new(mime.WordDecoder)
+ header, err := dec.Decode("=?utf-8?q?=C2=A1Hola,_se=C3=B1or!?=")
+ if err != nil {
+ panic(err)
+ }
+ fmt.Println(header)
+
+ dec.CharsetReader = func(charset string, input io.Reader) (io.Reader, error) {
+ switch charset {
+ case "x-case":
+ // Fake character set for example.
+ // Real use would integrate with packages such
+ // as code.google.com/p/go-charset
+ content, err := io.ReadAll(input)
+ if err != nil {
+ return nil, err
+ }
+ return bytes.NewReader(bytes.ToUpper(content)), nil
+ default:
+ return nil, fmt.Errorf("unhandled charset %q", charset)
+ }
+ }
+ header, err = dec.Decode("=?x-case?q?hello!?=")
+ if err != nil {
+ panic(err)
+ }
+ fmt.Println(header)
+ // Output:
+ // ¡Hola, señor!
+ // HELLO!
+}
+
+func ExampleWordDecoder_DecodeHeader() {
+ dec := new(mime.WordDecoder)
+ header, err := dec.DecodeHeader("=?utf-8?q?=C3=89ric?= , =?utf-8?q?Ana=C3=AFs?= ")
+ if err != nil {
+ panic(err)
+ }
+ fmt.Println(header)
+
+ header, err = dec.DecodeHeader("=?utf-8?q?=C2=A1Hola,?= =?utf-8?q?_se=C3=B1or!?=")
+ if err != nil {
+ panic(err)
+ }
+ fmt.Println(header)
+
+ dec.CharsetReader = func(charset string, input io.Reader) (io.Reader, error) {
+ switch charset {
+ case "x-case":
+ // Fake character set for example.
+ // Real use would integrate with packages such
+ // as code.google.com/p/go-charset
+ content, err := io.ReadAll(input)
+ if err != nil {
+ return nil, err
+ }
+ return bytes.NewReader(bytes.ToUpper(content)), nil
+ default:
+ return nil, fmt.Errorf("unhandled charset %q", charset)
+ }
+ }
+ header, err = dec.DecodeHeader("=?x-case?q?hello_?= =?x-case?q?world!?=")
+ if err != nil {
+ panic(err)
+ }
+ fmt.Println(header)
+ // Output:
+ // Éric , Anaïs
+ // ¡Hola, señor!
+ // HELLO WORLD!
+}
+
+func ExampleFormatMediaType() {
+ mediatype := "text/html"
+ params := map[string]string{
+ "charset": "utf-8",
+ }
+
+ result := mime.FormatMediaType(mediatype, params)
+
+ fmt.Println("result:", result)
+ // Output:
+ // result: text/html; charset=utf-8
+}
+
+func ExampleParseMediaType() {
+ mediatype, params, err := mime.ParseMediaType("text/html; charset=utf-8")
+ if err != nil {
+ panic(err)
+ }
+
+ fmt.Println("type:", mediatype)
+ fmt.Println("charset:", params["charset"])
+ // Output:
+ // type: text/html
+ // charset: utf-8
+}
diff --git a/go/src/mime/grammar.go b/go/src/mime/grammar.go
new file mode 100644
index 0000000000000000000000000000000000000000..1efd8a16dec607de16233b9279e4b45ff2f1a964
--- /dev/null
+++ b/go/src/mime/grammar.go
@@ -0,0 +1,85 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mime
+
+// isTSpecial reports whether c is in 'tspecials' as defined by RFC
+// 1521 and RFC 2045.
+func isTSpecial(c byte) bool {
+ // tspecials := "(" / ")" / "<" / ">" / "@" /
+ // "," / ";" / ":" / "\" / <">
+ // "/" / "[" / "]" / "?" / "="
+ //
+ // mask is a 128-bit bitmap with 1s for allowed bytes,
+ // so that the byte c can be tested with a shift and an and.
+ // If c >= 128, then 1<' |
+ 1<<'@' |
+ 1<<',' |
+ 1<<';' |
+ 1<<':' |
+ 1<<'\\' |
+ 1<<'"' |
+ 1<<'/' |
+ 1<<'[' |
+ 1<<']' |
+ 1<<'?' |
+ 1<<'='
+ return ((uint64(1)<>64)) != 0
+}
+
+// isTokenChar reports whether c is in 'token' as defined by RFC
+// 1521 and RFC 2045.
+func isTokenChar(c byte) bool {
+ // token := 1*
+ //
+ // mask is a 128-bit bitmap with 1s for allowed bytes,
+ // so that the byte c can be tested with a shift and an and.
+ // If c >= 128, then 1<>64)) != 0
+}
+
+// isToken reports whether s is a 'token' as defined by RFC 1521
+// and RFC 2045.
+func isToken(s string) bool {
+ if s == "" {
+ return false
+ }
+ for _, c := range []byte(s) {
+ if !isTokenChar(c) {
+ return false
+ }
+ }
+ return true
+}
diff --git a/go/src/mime/mediatype.go b/go/src/mime/mediatype.go
new file mode 100644
index 0000000000000000000000000000000000000000..c6006b614f319e06126d0b21a42ea9cf9487b011
--- /dev/null
+++ b/go/src/mime/mediatype.go
@@ -0,0 +1,402 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mime
+
+import (
+ "errors"
+ "fmt"
+ "maps"
+ "slices"
+ "strings"
+ "unicode"
+)
+
+// FormatMediaType serializes mediatype t and the parameters
+// param as a media type conforming to RFC 2045 and RFC 2616.
+// The type and parameter names are written in lower-case.
+// When any of the arguments result in a standard violation then
+// FormatMediaType returns the empty string.
+func FormatMediaType(t string, param map[string]string) string {
+ var b strings.Builder
+ if major, sub, ok := strings.Cut(t, "/"); !ok {
+ if !isToken(t) {
+ return ""
+ }
+ b.WriteString(strings.ToLower(t))
+ } else {
+ if !isToken(major) || !isToken(sub) {
+ return ""
+ }
+ b.WriteString(strings.ToLower(major))
+ b.WriteByte('/')
+ b.WriteString(strings.ToLower(sub))
+ }
+
+ for _, attribute := range slices.Sorted(maps.Keys(param)) {
+ value := param[attribute]
+ b.WriteByte(';')
+ b.WriteByte(' ')
+ if !isToken(attribute) {
+ return ""
+ }
+ b.WriteString(strings.ToLower(attribute))
+
+ needEnc := needsEncoding(value)
+ if needEnc {
+ // RFC 2231 section 4
+ b.WriteByte('*')
+ }
+ b.WriteByte('=')
+
+ if needEnc {
+ b.WriteString("utf-8''")
+
+ offset := 0
+ for index := 0; index < len(value); index++ {
+ ch := value[index]
+ // {RFC 2231 section 7}
+ // attribute-char :=
+ if ch <= ' ' || ch >= 0x7F ||
+ ch == '*' || ch == '\'' || ch == '%' ||
+ isTSpecial(ch) {
+
+ b.WriteString(value[offset:index])
+ offset = index + 1
+
+ b.WriteByte('%')
+ b.WriteByte(upperhex[ch>>4])
+ b.WriteByte(upperhex[ch&0x0F])
+ }
+ }
+ b.WriteString(value[offset:])
+ continue
+ }
+
+ if isToken(value) {
+ b.WriteString(value)
+ continue
+ }
+
+ b.WriteByte('"')
+ offset := 0
+ for index := 0; index < len(value); index++ {
+ character := value[index]
+ if character == '"' || character == '\\' {
+ b.WriteString(value[offset:index])
+ offset = index
+ b.WriteByte('\\')
+ }
+ }
+ b.WriteString(value[offset:])
+ b.WriteByte('"')
+ }
+ return b.String()
+}
+
+func checkMediaTypeDisposition(s string) error {
+ typ, rest := consumeToken(s)
+ if typ == "" {
+ return errNoMediaType
+ }
+ if rest == "" {
+ return nil
+ }
+ var ok bool
+ if rest, ok = strings.CutPrefix(rest, "/"); !ok {
+ return errNoSlashAfterFirstToken
+ }
+ subtype, rest := consumeToken(rest)
+ if subtype == "" {
+ return errNoTokenAfterSlash
+ }
+ if rest != "" {
+ return errUnexpectedContentAfterMediaSubtype
+ }
+ return nil
+}
+
+var (
+ errNoMediaType = errors.New("mime: no media type")
+ errNoSlashAfterFirstToken = errors.New("mime: expected slash after first token")
+ errNoTokenAfterSlash = errors.New("mime: expected token after slash")
+ errUnexpectedContentAfterMediaSubtype = errors.New("mime: unexpected content after media subtype")
+)
+
+// ErrInvalidMediaParameter is returned by [ParseMediaType] if
+// the media type value was found but there was an error parsing
+// the optional parameters
+var ErrInvalidMediaParameter = errors.New("mime: invalid media parameter")
+
+// ParseMediaType parses a media type value and any optional
+// parameters, per RFC 1521. Media types are the values in
+// Content-Type and Content-Disposition headers (RFC 2183).
+// On success, ParseMediaType returns the media type converted
+// to lowercase and trimmed of white space and a non-nil map.
+// If there is an error parsing the optional parameter,
+// the media type will be returned along with the error
+// [ErrInvalidMediaParameter].
+// The returned map, params, maps from the lowercase
+// attribute to the attribute value with its case preserved.
+func ParseMediaType(v string) (mediatype string, params map[string]string, err error) {
+ base, _, _ := strings.Cut(v, ";")
+ mediatype = strings.TrimSpace(strings.ToLower(base))
+
+ err = checkMediaTypeDisposition(mediatype)
+ if err != nil {
+ return "", nil, err
+ }
+
+ params = make(map[string]string)
+
+ // Map of base parameter name -> parameter name -> value
+ // for parameters containing a '*' character.
+ // Lazily initialized.
+ var continuation map[string]map[string]string
+
+ v = v[len(base):]
+ for len(v) > 0 {
+ v = strings.TrimLeftFunc(v, unicode.IsSpace)
+ if len(v) == 0 {
+ break
+ }
+ key, value, rest := consumeMediaParam(v)
+ if key == "" {
+ if strings.TrimSpace(rest) == ";" {
+ // Ignore trailing semicolons.
+ // Not an error.
+ break
+ }
+ // Parse error.
+ return mediatype, nil, ErrInvalidMediaParameter
+ }
+
+ pmap := params
+ if baseName, _, ok := strings.Cut(key, "*"); ok {
+ if continuation == nil {
+ continuation = make(map[string]map[string]string)
+ }
+ if pmap, ok = continuation[baseName]; !ok {
+ continuation[baseName] = make(map[string]string)
+ pmap = continuation[baseName]
+ }
+ }
+ if v, exists := pmap[key]; exists && v != value {
+ // Duplicate parameter names are incorrect, but we allow them if they are equal.
+ return "", nil, errDuplicateParamName
+ }
+ pmap[key] = value
+ v = rest
+ }
+
+ // Stitch together any continuations or things with stars
+ // (i.e. RFC 2231 things with stars: "foo*0" or "foo*")
+ var buf strings.Builder
+ for key, pieceMap := range continuation {
+ singlePartKey := key + "*"
+ if v, ok := pieceMap[singlePartKey]; ok {
+ if decv, ok := decode2231Enc(v); ok {
+ params[key] = decv
+ }
+ continue
+ }
+
+ buf.Reset()
+ valid := false
+ for n := 0; ; n++ {
+ simplePart := fmt.Sprintf("%s*%d", key, n)
+ if v, ok := pieceMap[simplePart]; ok {
+ valid = true
+ buf.WriteString(v)
+ continue
+ }
+ encodedPart := simplePart + "*"
+ v, ok := pieceMap[encodedPart]
+ if !ok {
+ break
+ }
+ valid = true
+ if n == 0 {
+ if decv, ok := decode2231Enc(v); ok {
+ buf.WriteString(decv)
+ }
+ } else {
+ decv, _ := percentHexUnescape(v)
+ buf.WriteString(decv)
+ }
+ }
+ if valid {
+ params[key] = buf.String()
+ }
+ }
+
+ return
+}
+
+var errDuplicateParamName = errors.New("mime: duplicate parameter name")
+
+func decode2231Enc(v string) (string, bool) {
+ charset, v, ok := strings.Cut(v, "'")
+ if !ok {
+ return "", false
+ }
+ // TODO: ignoring the language part for now. If anybody needs it, we'll
+ // need to decide how to expose it in the API. But I'm not sure
+ // anybody uses it in practice.
+ _, extOtherVals, ok := strings.Cut(v, "'")
+ if !ok {
+ return "", false
+ }
+ charset = strings.ToLower(charset)
+ switch charset {
+ case "us-ascii", "utf-8":
+ default:
+ // Empty or unsupported encoding.
+ return "", false
+ }
+ return percentHexUnescape(extOtherVals)
+}
+
+// consumeToken consumes a token from the beginning of provided
+// string, per RFC 2045 section 5.1 (referenced from 2183), and return
+// the token consumed and the rest of the string. Returns ("", v) on
+// failure to consume at least one character.
+func consumeToken(v string) (token, rest string) {
+ for i := range len(v) {
+ if !isTokenChar(v[i]) {
+ return v[:i], v[i:]
+ }
+ }
+ return v, ""
+}
+
+// consumeValue consumes a "value" per RFC 2045, where a value is
+// either a 'token' or a 'quoted-string'. On success, consumeValue
+// returns the value consumed (and de-quoted/escaped, if a
+// quoted-string) and the rest of the string. On failure, returns
+// ("", v).
+func consumeValue(v string) (value, rest string) {
+ if v == "" {
+ return
+ }
+ if v[0] != '"' {
+ return consumeToken(v)
+ }
+
+ // parse a quoted-string
+ buffer := new(strings.Builder)
+ for i := 1; i < len(v); i++ {
+ r := v[i]
+ if r == '"' {
+ return buffer.String(), v[i+1:]
+ }
+ // When MSIE sends a full file path (in "intranet mode"), it does not
+ // escape backslashes: "C:\dev\go\foo.txt", not "C:\\dev\\go\\foo.txt".
+ //
+ // No known MIME generators emit unnecessary backslash escapes
+ // for simple token characters like numbers and letters.
+ //
+ // If we see an unnecessary backslash escape, assume it is from MSIE
+ // and intended as a literal backslash. This makes Go servers deal better
+ // with MSIE without affecting the way they handle conforming MIME
+ // generators.
+ if r == '\\' && i+1 < len(v) && isTSpecial(v[i+1]) {
+ buffer.WriteByte(v[i+1])
+ i++
+ continue
+ }
+ if r == '\r' || r == '\n' {
+ return "", v
+ }
+ buffer.WriteByte(v[i])
+ }
+ // Did not find end quote.
+ return "", v
+}
+
+func consumeMediaParam(v string) (param, value, rest string) {
+ rest = strings.TrimLeftFunc(v, unicode.IsSpace)
+ var ok bool
+ if rest, ok = strings.CutPrefix(rest, ";"); !ok {
+ return "", "", v
+ }
+
+ rest = strings.TrimLeftFunc(rest, unicode.IsSpace)
+ param, rest = consumeToken(rest)
+ param = strings.ToLower(param)
+ if param == "" {
+ return "", "", v
+ }
+
+ rest = strings.TrimLeftFunc(rest, unicode.IsSpace)
+ if rest, ok = strings.CutPrefix(rest, "="); !ok {
+ return "", "", v
+ }
+ rest = strings.TrimLeftFunc(rest, unicode.IsSpace)
+ value, rest2 := consumeValue(rest)
+ if value == "" && rest2 == rest {
+ return "", "", v
+ }
+ rest = rest2
+ return param, value, rest
+}
+
+func percentHexUnescape(s string) (string, bool) {
+ // Count %, check that they're well-formed.
+ percents := 0
+ for i := 0; i < len(s); {
+ if s[i] != '%' {
+ i++
+ continue
+ }
+ percents++
+ if i+2 >= len(s) || !ishex(s[i+1]) || !ishex(s[i+2]) {
+ return "", false
+ }
+ i += 3
+ }
+ if percents == 0 {
+ return s, true
+ }
+
+ t := make([]byte, len(s)-2*percents)
+ j := 0
+ for i := 0; i < len(s); {
+ switch s[i] {
+ case '%':
+ t[j] = unhex(s[i+1])<<4 | unhex(s[i+2])
+ j++
+ i += 3
+ default:
+ t[j] = s[i]
+ j++
+ i++
+ }
+ }
+ return string(t), true
+}
+
+func ishex(c byte) bool {
+ switch {
+ case '0' <= c && c <= '9':
+ return true
+ case 'a' <= c && c <= 'f':
+ return true
+ case 'A' <= c && c <= 'F':
+ return true
+ }
+ return false
+}
+
+func unhex(c byte) byte {
+ switch {
+ case '0' <= c && c <= '9':
+ return c - '0'
+ case 'a' <= c && c <= 'f':
+ return c - 'a' + 10
+ case 'A' <= c && c <= 'F':
+ return c - 'A' + 10
+ }
+ return 0
+}
diff --git a/go/src/mime/mediatype_test.go b/go/src/mime/mediatype_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..da8d64de7a3f0cbc7c855fd002fbb65e8a5a9d15
--- /dev/null
+++ b/go/src/mime/mediatype_test.go
@@ -0,0 +1,564 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mime
+
+import (
+ "maps"
+ "strings"
+ "testing"
+)
+
+func TestConsumeToken(t *testing.T) {
+ tests := [...][3]string{
+ {"foo bar", "foo", " bar"},
+ {"bar", "bar", ""},
+ {"", "", ""},
+ {" foo", "", " foo"},
+ }
+ for _, test := range tests {
+ token, rest := consumeToken(test[0])
+ expectedToken := test[1]
+ expectedRest := test[2]
+ if token != expectedToken {
+ t.Errorf("expected to consume token '%s', not '%s' from '%s'",
+ expectedToken, token, test[0])
+ } else if rest != expectedRest {
+ t.Errorf("expected to have left '%s', not '%s' after reading token '%s' from '%s'",
+ expectedRest, rest, token, test[0])
+ }
+ }
+}
+
+func TestConsumeValue(t *testing.T) {
+ tests := [...][3]string{
+ {"foo bar", "foo", " bar"},
+ {"bar", "bar", ""},
+ {" bar ", "", " bar "},
+ {`"My value"end`, "My value", "end"},
+ {`"My value" end`, "My value", " end"},
+ {`"\\" rest`, "\\", " rest"},
+ {`"My \" value"end`, "My \" value", "end"},
+ {`"\" rest`, "", `"\" rest`},
+ {`"C:\dev\go\robots.txt"`, `C:\dev\go\robots.txt`, ""},
+ {`"C:\新建文件夹\中文第二次测试.mp4"`, `C:\新建文件夹\中文第二次测试.mp4`, ""},
+ }
+ for _, test := range tests {
+ value, rest := consumeValue(test[0])
+ expectedValue := test[1]
+ expectedRest := test[2]
+ if value != expectedValue {
+ t.Errorf("expected to consume value [%s], not [%s] from [%s]",
+ expectedValue, value, test[0])
+ } else if rest != expectedRest {
+ t.Errorf("expected to have left [%s], not [%s] after reading value [%s] from [%s]",
+ expectedRest, rest, value, test[0])
+ }
+ }
+}
+
+func TestConsumeMediaParam(t *testing.T) {
+ tests := [...][4]string{
+ {" ; foo=bar", "foo", "bar", ""},
+ {"; foo=bar", "foo", "bar", ""},
+ {";foo=bar", "foo", "bar", ""},
+ {";FOO=bar", "foo", "bar", ""},
+ {`;foo="bar"`, "foo", "bar", ""},
+ {`;foo="bar"; `, "foo", "bar", "; "},
+ {`;foo="bar"; foo=baz`, "foo", "bar", "; foo=baz"},
+ {` ; boundary=----CUT;`, "boundary", "----CUT", ";"},
+ {` ; key=value; blah="value";name="foo" `, "key", "value", `; blah="value";name="foo" `},
+ {`; blah="value";name="foo" `, "blah", "value", `;name="foo" `},
+ {`;name="foo" `, "name", "foo", ` `},
+ }
+ for _, test := range tests {
+ param, value, rest := consumeMediaParam(test[0])
+ expectedParam := test[1]
+ expectedValue := test[2]
+ expectedRest := test[3]
+ if param != expectedParam {
+ t.Errorf("expected to consume param [%s], not [%s] from [%s]",
+ expectedParam, param, test[0])
+ } else if value != expectedValue {
+ t.Errorf("expected to consume value [%s], not [%s] from [%s]",
+ expectedValue, value, test[0])
+ } else if rest != expectedRest {
+ t.Errorf("expected to have left [%s], not [%s] after reading [%s/%s] from [%s]",
+ expectedRest, rest, param, value, test[0])
+ }
+ }
+}
+
+type mediaTypeTest struct {
+ in string
+ t string
+ p map[string]string
+}
+
+var parseMediaTypeTests []mediaTypeTest
+
+func init() {
+ // Convenience map initializer
+ m := func(s ...string) map[string]string {
+ sm := make(map[string]string)
+ for i := 0; i < len(s); i += 2 {
+ sm[s[i]] = s[i+1]
+ }
+ return sm
+ }
+
+ nameFoo := map[string]string{"name": "foo"}
+ parseMediaTypeTests = []mediaTypeTest{
+ {`form-data; name="foo"`, "form-data", nameFoo},
+ {` form-data ; name=foo`, "form-data", nameFoo},
+ {`FORM-DATA;name="foo"`, "form-data", nameFoo},
+ {` FORM-DATA ; name="foo"`, "form-data", nameFoo},
+ {` FORM-DATA ; name="foo"`, "form-data", nameFoo},
+
+ {`form-data; key=value; blah="value";name="foo" `,
+ "form-data",
+ m("key", "value", "blah", "value", "name", "foo")},
+
+ {`foo; key=val1; key=the-key-appears-again-which-is-bogus`,
+ "", m()},
+
+ // From RFC 2231:
+ {`application/x-stuff; title*=us-ascii'en-us'This%20is%20%2A%2A%2Afun%2A%2A%2A`,
+ "application/x-stuff",
+ m("title", "This is ***fun***")},
+
+ {`message/external-body; access-type=URL; ` +
+ `URL*0="ftp://";` +
+ `URL*1="cs.utk.edu/pub/moore/bulk-mailer/bulk-mailer.tar"`,
+ "message/external-body",
+ m("access-type", "URL",
+ "url", "ftp://cs.utk.edu/pub/moore/bulk-mailer/bulk-mailer.tar")},
+
+ {`application/x-stuff; ` +
+ `title*0*=us-ascii'en'This%20is%20even%20more%20; ` +
+ `title*1*=%2A%2A%2Afun%2A%2A%2A%20; ` +
+ `title*2="isn't it!"`,
+ "application/x-stuff",
+ m("title", "This is even more ***fun*** isn't it!")},
+
+ // Tests from http://greenbytes.de/tech/tc2231/
+ // Note: Backslash escape handling is a bit loose, like MSIE.
+
+ // #attonly
+ {`attachment`,
+ "attachment",
+ m()},
+ // #attonlyucase
+ {`ATTACHMENT`,
+ "attachment",
+ m()},
+ // #attwithasciifilename
+ {`attachment; filename="foo.html"`,
+ "attachment",
+ m("filename", "foo.html")},
+ // #attwithasciifilename25
+ {`attachment; filename="0000000000111111111122222"`,
+ "attachment",
+ m("filename", "0000000000111111111122222")},
+ // #attwithasciifilename35
+ {`attachment; filename="00000000001111111111222222222233333"`,
+ "attachment",
+ m("filename", "00000000001111111111222222222233333")},
+ // #attwithasciifnescapedchar
+ {`attachment; filename="f\oo.html"`,
+ "attachment",
+ m("filename", "f\\oo.html")},
+ // #attwithasciifnescapedquote
+ {`attachment; filename="\"quoting\" tested.html"`,
+ "attachment",
+ m("filename", `"quoting" tested.html`)},
+ // #attwithquotedsemicolon
+ {`attachment; filename="Here's a semicolon;.html"`,
+ "attachment",
+ m("filename", "Here's a semicolon;.html")},
+ // #attwithfilenameandextparam
+ {`attachment; foo="bar"; filename="foo.html"`,
+ "attachment",
+ m("foo", "bar", "filename", "foo.html")},
+ // #attwithfilenameandextparamescaped
+ {`attachment; foo="\"\\";filename="foo.html"`,
+ "attachment",
+ m("foo", "\"\\", "filename", "foo.html")},
+ // #attwithasciifilenameucase
+ {`attachment; FILENAME="foo.html"`,
+ "attachment",
+ m("filename", "foo.html")},
+ // #attwithasciifilenamenq
+ {`attachment; filename=foo.html`,
+ "attachment",
+ m("filename", "foo.html")},
+ // #attwithasciifilenamenqs
+ {`attachment; filename=foo.html ;`,
+ "attachment",
+ m("filename", "foo.html")},
+ // #attwithfntokensq
+ {`attachment; filename='foo.html'`,
+ "attachment",
+ m("filename", "'foo.html'")},
+ // #attwithisofnplain
+ {`attachment; filename="foo-ä.html"`,
+ "attachment",
+ m("filename", "foo-ä.html")},
+ // #attwithutf8fnplain
+ {`attachment; filename="foo-ä.html"`,
+ "attachment",
+ m("filename", "foo-ä.html")},
+ // #attwithfnrawpctenca
+ {`attachment; filename="foo-%41.html"`,
+ "attachment",
+ m("filename", "foo-%41.html")},
+ // #attwithfnusingpct
+ {`attachment; filename="50%.html"`,
+ "attachment",
+ m("filename", "50%.html")},
+ // #attwithfnrawpctencaq
+ {`attachment; filename="foo-%\41.html"`,
+ "attachment",
+ m("filename", "foo-%\\41.html")},
+ // #attwithnamepct
+ {`attachment; name="foo-%41.html"`,
+ "attachment",
+ m("name", "foo-%41.html")},
+ // #attwithfilenamepctandiso
+ {`attachment; name="ä-%41.html"`,
+ "attachment",
+ m("name", "ä-%41.html")},
+ // #attwithfnrawpctenclong
+ {`attachment; filename="foo-%c3%a4-%e2%82%ac.html"`,
+ "attachment",
+ m("filename", "foo-%c3%a4-%e2%82%ac.html")},
+ // #attwithasciifilenamews1
+ {`attachment; filename ="foo.html"`,
+ "attachment",
+ m("filename", "foo.html")},
+ // #attmissingdisposition
+ {`filename=foo.html`,
+ "", m()},
+ // #attmissingdisposition2
+ {`x=y; filename=foo.html`,
+ "", m()},
+ // #attmissingdisposition3
+ {`"foo; filename=bar;baz"; filename=qux`,
+ "", m()},
+ // #attmissingdisposition4
+ {`filename=foo.html, filename=bar.html`,
+ "", m()},
+ // #emptydisposition
+ {`; filename=foo.html`,
+ "", m()},
+ // #doublecolon
+ {`: inline; attachment; filename=foo.html`,
+ "", m()},
+ // #attandinline
+ {`inline; attachment; filename=foo.html`,
+ "", m()},
+ // #attandinline2
+ {`attachment; inline; filename=foo.html`,
+ "", m()},
+ // #attbrokenquotedfn
+ {`attachment; filename="foo.html".txt`,
+ "", m()},
+ // #attbrokenquotedfn2
+ {`attachment; filename="bar`,
+ "", m()},
+ // #attbrokenquotedfn3
+ {`attachment; filename=foo"bar;baz"qux`,
+ "", m()},
+ // #attmultinstances
+ {`attachment; filename=foo.html, attachment; filename=bar.html`,
+ "", m()},
+ // #attmissingdelim
+ {`attachment; foo=foo filename=bar`,
+ "", m()},
+ // #attmissingdelim2
+ {`attachment; filename=bar foo=foo`,
+ "", m()},
+ // #attmissingdelim3
+ {`attachment filename=bar`,
+ "", m()},
+ // #attreversed
+ {`filename=foo.html; attachment`,
+ "", m()},
+ // #attconfusedparam
+ {`attachment; xfilename=foo.html`,
+ "attachment",
+ m("xfilename", "foo.html")},
+ // #attcdate
+ {`attachment; creation-date="Wed, 12 Feb 1997 16:29:51 -0500"`,
+ "attachment",
+ m("creation-date", "Wed, 12 Feb 1997 16:29:51 -0500")},
+ // #attmdate
+ {`attachment; modification-date="Wed, 12 Feb 1997 16:29:51 -0500"`,
+ "attachment",
+ m("modification-date", "Wed, 12 Feb 1997 16:29:51 -0500")},
+ // #dispext
+ {`foobar`, "foobar", m()},
+ // #dispextbadfn
+ {`attachment; example="filename=example.txt"`,
+ "attachment",
+ m("example", "filename=example.txt")},
+ // #attwithfn2231utf8
+ {`attachment; filename*=UTF-8''foo-%c3%a4-%e2%82%ac.html`,
+ "attachment",
+ m("filename", "foo-ä-€.html")},
+ // #attwithfn2231noc
+ {`attachment; filename*=''foo-%c3%a4-%e2%82%ac.html`,
+ "attachment",
+ m()},
+ // #attwithfn2231utf8comp
+ {`attachment; filename*=UTF-8''foo-a%cc%88.html`,
+ "attachment",
+ m("filename", "foo-ä.html")},
+ // #attwithfn2231ws2
+ {`attachment; filename*= UTF-8''foo-%c3%a4.html`,
+ "attachment",
+ m("filename", "foo-ä.html")},
+ // #attwithfn2231ws3
+ {`attachment; filename* =UTF-8''foo-%c3%a4.html`,
+ "attachment",
+ m("filename", "foo-ä.html")},
+ // #attwithfn2231quot
+ {`attachment; filename*="UTF-8''foo-%c3%a4.html"`,
+ "attachment",
+ m("filename", "foo-ä.html")},
+ // #attwithfn2231quot2
+ {`attachment; filename*="foo%20bar.html"`,
+ "attachment",
+ m()},
+ // #attwithfn2231singleqmissing
+ {`attachment; filename*=UTF-8'foo-%c3%a4.html`,
+ "attachment",
+ m()},
+ // #attwithfn2231nbadpct1
+ {`attachment; filename*=UTF-8''foo%`,
+ "attachment",
+ m()},
+ // #attwithfn2231nbadpct2
+ {`attachment; filename*=UTF-8''f%oo.html`,
+ "attachment",
+ m()},
+ // #attwithfn2231dpct
+ {`attachment; filename*=UTF-8''A-%2541.html`,
+ "attachment",
+ m("filename", "A-%41.html")},
+ // #attfncont
+ {`attachment; filename*0="foo."; filename*1="html"`,
+ "attachment",
+ m("filename", "foo.html")},
+ // #attfncontenc
+ {`attachment; filename*0*=UTF-8''foo-%c3%a4; filename*1=".html"`,
+ "attachment",
+ m("filename", "foo-ä.html")},
+ // #attfncontlz
+ {`attachment; filename*0="foo"; filename*01="bar"`,
+ "attachment",
+ m("filename", "foo")},
+ // #attfncontnc
+ {`attachment; filename*0="foo"; filename*2="bar"`,
+ "attachment",
+ m("filename", "foo")},
+ // #attfnconts1
+ {`attachment; filename*1="foo."; filename*2="html"`,
+ "attachment", m()},
+ // #attfncontord
+ {`attachment; filename*1="bar"; filename*0="foo"`,
+ "attachment",
+ m("filename", "foobar")},
+ // #attfnboth
+ {`attachment; filename="foo-ae.html"; filename*=UTF-8''foo-%c3%a4.html`,
+ "attachment",
+ m("filename", "foo-ä.html")},
+ // #attfnboth2
+ {`attachment; filename*=UTF-8''foo-%c3%a4.html; filename="foo-ae.html"`,
+ "attachment",
+ m("filename", "foo-ä.html")},
+ // #attfnboth3
+ {`attachment; filename*0*=ISO-8859-15''euro-sign%3d%a4; filename*=ISO-8859-1''currency-sign%3d%a4`,
+ "attachment",
+ m()},
+ // #attnewandfn
+ {`attachment; foobar=x; filename="foo.html"`,
+ "attachment",
+ m("foobar", "x", "filename", "foo.html")},
+
+ // Browsers also just send UTF-8 directly without RFC 2231,
+ // at least when the source page is served with UTF-8.
+ {`form-data; firstname="Брэд"; lastname="Фицпатрик"`,
+ "form-data",
+ m("firstname", "Брэд", "lastname", "Фицпатрик")},
+
+ // Empty string used to be mishandled.
+ {`foo; bar=""`, "foo", m("bar", "")},
+
+ // Microsoft browsers in intranet mode do not think they need to escape \ in file name.
+ {`form-data; name="file"; filename="C:\dev\go\robots.txt"`, "form-data", m("name", "file", "filename", `C:\dev\go\robots.txt`)},
+ {`form-data; name="file"; filename="C:\新建文件夹\中文第二次测试.mp4"`, "form-data", m("name", "file", "filename", `C:\新建文件夹\中文第二次测试.mp4`)},
+
+ // issue #46323 (https://github.com/golang/go/issues/46323)
+ {
+ // example from rfc2231-p.3 (https://datatracker.ietf.org/doc/html/rfc2231)
+ `message/external-body; access-type=URL;
+ URL*0="ftp://";
+ URL*1="cs.utk.edu/pub/moore/bulk-mailer/bulk-mailer.tar";`, // <-- trailing semicolon
+ `message/external-body`,
+ m("access-type", "URL", "url", "ftp://cs.utk.edu/pub/moore/bulk-mailer/bulk-mailer.tar"),
+ },
+
+ // Issue #48866: duplicate parameters containing equal values should be allowed
+ {`text; charset=utf-8; charset=utf-8; format=fixed`, "text", m("charset", "utf-8", "format", "fixed")},
+ {`text; charset=utf-8; format=flowed; charset=utf-8`, "text", m("charset", "utf-8", "format", "flowed")},
+
+ // Issue #76236: '{' and '}' are token chars.
+ {"attachment; filename={file}.png", "attachment", m("filename", "{file}.png")},
+ }
+}
+
+func TestParseMediaType(t *testing.T) {
+ for _, test := range parseMediaTypeTests {
+ mt, params, err := ParseMediaType(test.in)
+ if err != nil {
+ if test.t != "" {
+ t.Errorf("for input %#q, unexpected error: %v", test.in, err)
+ continue
+ }
+ continue
+ }
+ if g, e := mt, test.t; g != e {
+ t.Errorf("for input %#q, expected type %q, got %q",
+ test.in, e, g)
+ continue
+ }
+ if len(params) == 0 && len(test.p) == 0 {
+ continue
+ }
+ if !maps.Equal(params, test.p) {
+ t.Errorf("for input %#q, wrong params.\n"+
+ "expected: %#v\n"+
+ " got: %#v",
+ test.in, test.p, params)
+ }
+ }
+}
+
+func BenchmarkParseMediaType(b *testing.B) {
+ for range b.N {
+ for _, test := range parseMediaTypeTests {
+ ParseMediaType(test.in)
+ }
+ }
+}
+
+type badMediaTypeTest struct {
+ in string
+ mt string
+ err string
+}
+
+var badMediaTypeTests = []badMediaTypeTest{
+ {"bogus ;=========", "bogus", "mime: invalid media parameter"},
+ // The following example is from real email delivered by gmail (error: missing semicolon)
+ // and it is there to check behavior described in #19498
+ {"application/pdf; x-mac-type=\"3F3F3F3F\"; x-mac-creator=\"3F3F3F3F\" name=\"a.pdf\";",
+ "application/pdf", "mime: invalid media parameter"},
+ {"bogus/", "", "mime: expected token after slash"},
+ {"bogus/bogus", "", "mime: unexpected content after media subtype"},
+ // Tests from http://greenbytes.de/tech/tc2231/
+ {`"attachment"`, "attachment", "mime: no media type"},
+ {"attachment; filename=foo,bar.html", "attachment", "mime: invalid media parameter"},
+ {"attachment; ;filename=foo", "attachment", "mime: invalid media parameter"},
+ {"attachment; filename=foo bar.html", "attachment", "mime: invalid media parameter"},
+ {`attachment; filename="foo.html"; filename="bar.html"`, "attachment", "mime: duplicate parameter name"},
+ {"attachment; filename=foo[1](2).html", "attachment", "mime: invalid media parameter"},
+ {"attachment; filename=foo-ä.html", "attachment", "mime: invalid media parameter"},
+ {"attachment; filename=foo-ä.html", "attachment", "mime: invalid media parameter"},
+ {`attachment; filename *=UTF-8''foo-%c3%a4.html`, "attachment", "mime: invalid media parameter"},
+}
+
+func TestParseMediaTypeBogus(t *testing.T) {
+ for _, tt := range badMediaTypeTests {
+ mt, params, err := ParseMediaType(tt.in)
+ if err == nil {
+ t.Errorf("ParseMediaType(%q) = nil error; want parse error", tt.in)
+ continue
+ }
+ if err.Error() != tt.err {
+ t.Errorf("ParseMediaType(%q) = err %q; want %q", tt.in, err.Error(), tt.err)
+ }
+ if params != nil {
+ t.Errorf("ParseMediaType(%q): got non-nil params on error", tt.in)
+ }
+ if err != ErrInvalidMediaParameter && mt != "" {
+ t.Errorf("ParseMediaType(%q): got unexpected non-empty media type string", tt.in)
+ }
+ if err == ErrInvalidMediaParameter && mt != tt.mt {
+ t.Errorf("ParseMediaType(%q): in case of invalid parameters: expected type %q, got %q", tt.in, tt.mt, mt)
+ }
+ }
+}
+
+func BenchmarkParseMediaTypeBogus(b *testing.B) {
+ for range b.N {
+ for _, test := range badMediaTypeTests {
+ ParseMediaType(test.in)
+ }
+ }
+}
+
+type formatTest struct {
+ typ string
+ params map[string]string
+ want string
+}
+
+var formatTests = []formatTest{
+ {"noslash", map[string]string{"X": "Y"}, "noslash; x=Y"}, // e.g. Content-Disposition values (RFC 2183); issue 11289
+ {"foo bar/baz", nil, ""},
+ {"foo/bar baz", nil, ""},
+ {"attachment", map[string]string{"filename": "ĄĄŽŽČČŠŠ"}, "attachment; filename*=utf-8''%C4%84%C4%84%C5%BD%C5%BD%C4%8C%C4%8C%C5%A0%C5%A0"},
+ {"attachment", map[string]string{"filename": "ÁÁÊÊÇÇÎÎ"}, "attachment; filename*=utf-8''%C3%81%C3%81%C3%8A%C3%8A%C3%87%C3%87%C3%8E%C3%8E"},
+ {"attachment", map[string]string{"filename": "数据统计.png"}, "attachment; filename*=utf-8''%E6%95%B0%E6%8D%AE%E7%BB%9F%E8%AE%A1.png"},
+ {"foo/BAR", nil, "foo/bar"},
+ {"foo/BAR", map[string]string{"X": "Y"}, "foo/bar; x=Y"},
+ {"foo/BAR", map[string]string{"space": "With space"}, `foo/bar; space="With space"`},
+ {"foo/BAR", map[string]string{"quote": `With "quote`}, `foo/bar; quote="With \"quote"`},
+ {"foo/BAR", map[string]string{"bslash": `With \backslash`}, `foo/bar; bslash="With \\backslash"`},
+ {"foo/BAR", map[string]string{"both": `With \backslash and "quote`}, `foo/bar; both="With \\backslash and \"quote"`},
+ {"foo/BAR", map[string]string{"": "empty attribute"}, ""},
+ {"foo/BAR", map[string]string{"bad attribute": "baz"}, ""},
+ {"foo/BAR", map[string]string{"nonascii": "not an ascii character: ä"}, "foo/bar; nonascii*=utf-8''not%20an%20ascii%20character%3A%20%C3%A4"},
+ {"foo/BAR", map[string]string{"ctl": "newline: \n nil: \000"}, "foo/bar; ctl*=utf-8''newline%3A%20%0A%20nil%3A%20%00"},
+ {"foo/bar", map[string]string{"a": "av", "b": "bv", "c": "cv"}, "foo/bar; a=av; b=bv; c=cv"},
+ {"foo/bar", map[string]string{"0": "'", "9": "'"}, "foo/bar; 0='; 9='"},
+ {"foo", map[string]string{"bar": ""}, `foo; bar=""`},
+}
+
+func TestFormatMediaType(t *testing.T) {
+ for i, tt := range formatTests {
+ got := FormatMediaType(tt.typ, tt.params)
+ if got != tt.want {
+ t.Errorf("%d. FormatMediaType(%q, %v) = %q; want %q", i, tt.typ, tt.params, got, tt.want)
+ }
+ if got == "" {
+ continue
+ }
+ typ, params, err := ParseMediaType(got)
+ if err != nil {
+ t.Errorf("%d. ParseMediaType(%q) err: %v", i, got, err)
+ }
+ if typ != strings.ToLower(tt.typ) {
+ t.Errorf("%d. ParseMediaType(%q) typ = %q; want %q", i, got, typ, tt.typ)
+ }
+ for k, v := range tt.params {
+ k = strings.ToLower(k)
+ if params[k] != v {
+ t.Errorf("%d. ParseMediaType(%q) params[%s] = %q; want %q", i, got, k, params[k], v)
+ }
+ }
+ }
+}
diff --git a/go/src/mime/type.go b/go/src/mime/type.go
new file mode 100644
index 0000000000000000000000000000000000000000..58cc22fdb0135c331b0cc2d3fd6f409d6eca807e
--- /dev/null
+++ b/go/src/mime/type.go
@@ -0,0 +1,268 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package mime implements parts of the MIME spec.
+package mime
+
+import (
+ "fmt"
+ "slices"
+ "strings"
+ "sync"
+)
+
+var (
+ mimeTypes sync.Map // map[string]string; ".Z" => "application/x-compress"
+ mimeTypesLower sync.Map // map[string]string; ".z" => "application/x-compress"
+
+ // extensions maps from MIME type to list of lowercase file
+ // extensions: "image/jpeg" => [".jfif", ".jpg", ".jpeg", ".pjp", ".pjpeg"]
+ extensionsMu sync.Mutex // Guards stores (but not loads) on extensions.
+ extensions sync.Map // map[string][]string; slice values are append-only.
+)
+
+// setMimeTypes is used by initMime's non-test path, and by tests.
+func setMimeTypes(lowerExt, mixExt map[string]string) {
+ mimeTypes.Clear()
+ mimeTypesLower.Clear()
+ extensions.Clear()
+
+ for k, v := range lowerExt {
+ mimeTypesLower.Store(k, v)
+ }
+ for k, v := range mixExt {
+ mimeTypes.Store(k, v)
+ }
+
+ extensionsMu.Lock()
+ defer extensionsMu.Unlock()
+ for k, v := range lowerExt {
+ justType, _, err := ParseMediaType(v)
+ if err != nil {
+ panic(err)
+ }
+ var exts []string
+ if ei, ok := extensions.Load(justType); ok {
+ exts = ei.([]string)
+ }
+ extensions.Store(justType, append(exts, k))
+ }
+}
+
+// A type is listed here if both Firefox and Chrome included them in their own
+// lists. In the case where they contradict they are deconflicted using IANA's
+// listed media types https://www.iana.org/assignments/media-types/media-types.xhtml
+//
+// Chrome's MIME mappings to file extensions are defined at
+// https://chromium.googlesource.com/chromium/src.git/+/refs/heads/main/net/base/mime_util.cc
+//
+// Firefox's MIME types can be found at
+// https://github.com/mozilla-firefox/firefox/blob/main/netwerk/mime/nsMimeTypes.h
+// and the mappings to file extensions at
+// https://github.com/mozilla-firefox/firefox/blob/main/uriloader/exthandler/nsExternalHelperAppService.cpp
+var builtinTypesLower = map[string]string{
+ ".ai": "application/postscript",
+ ".apk": "application/vnd.android.package-archive",
+ ".apng": "image/apng",
+ ".avif": "image/avif",
+ ".bin": "application/octet-stream",
+ ".bmp": "image/bmp",
+ ".com": "application/octet-stream",
+ ".css": "text/css; charset=utf-8",
+ ".csv": "text/csv; charset=utf-8",
+ ".doc": "application/msword",
+ ".docx": "application/vnd.openxmlformats-officedocument.wordprocessingml.document",
+ ".ehtml": "text/html; charset=utf-8",
+ ".eml": "message/rfc822",
+ ".eps": "application/postscript",
+ ".exe": "application/octet-stream",
+ ".flac": "audio/flac",
+ ".gif": "image/gif",
+ ".gz": "application/gzip",
+ ".htm": "text/html; charset=utf-8",
+ ".html": "text/html; charset=utf-8",
+ ".ico": "image/vnd.microsoft.icon",
+ ".ics": "text/calendar; charset=utf-8",
+ ".jfif": "image/jpeg",
+ ".jpeg": "image/jpeg",
+ ".jpg": "image/jpeg",
+ ".js": "text/javascript; charset=utf-8",
+ ".json": "application/json",
+ ".m4a": "audio/mp4",
+ ".mjs": "text/javascript; charset=utf-8",
+ ".mp3": "audio/mpeg",
+ ".mp4": "video/mp4",
+ ".oga": "audio/ogg",
+ ".ogg": "audio/ogg",
+ ".ogv": "video/ogg",
+ ".opus": "audio/ogg",
+ ".pdf": "application/pdf",
+ ".pjp": "image/jpeg",
+ ".pjpeg": "image/jpeg",
+ ".png": "image/png",
+ ".ppt": "application/vnd.ms-powerpoint",
+ ".pptx": "application/vnd.openxmlformats-officedocument.presentationml.presentation",
+ ".ps": "application/postscript",
+ ".rdf": "application/rdf+xml",
+ ".rtf": "application/rtf",
+ ".shtml": "text/html; charset=utf-8",
+ ".svg": "image/svg+xml",
+ ".text": "text/plain; charset=utf-8",
+ ".tif": "image/tiff",
+ ".tiff": "image/tiff",
+ ".txt": "text/plain; charset=utf-8",
+ ".vtt": "text/vtt; charset=utf-8",
+ ".wasm": "application/wasm",
+ ".wav": "audio/wav",
+ ".webm": "audio/webm",
+ ".webp": "image/webp",
+ ".xbl": "text/xml; charset=utf-8",
+ ".xbm": "image/x-xbitmap",
+ ".xht": "application/xhtml+xml",
+ ".xhtml": "application/xhtml+xml",
+ ".xls": "application/vnd.ms-excel",
+ ".xlsx": "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
+ ".xml": "text/xml; charset=utf-8",
+ ".xsl": "text/xml; charset=utf-8",
+ ".zip": "application/zip",
+}
+
+var once sync.Once // guards initMime
+
+var testInitMime, osInitMime func()
+
+func initMime() {
+ if fn := testInitMime; fn != nil {
+ fn()
+ } else {
+ setMimeTypes(builtinTypesLower, builtinTypesLower)
+ osInitMime()
+ }
+}
+
+// TypeByExtension returns the MIME type associated with the file extension ext.
+// The extension ext should begin with a leading dot, as in ".html".
+// When ext has no associated type, TypeByExtension returns "".
+//
+// Extensions are looked up first case-sensitively, then case-insensitively.
+//
+// The built-in table is small but on unix it is augmented by the local
+// system's MIME-info database or mime.types file(s) if available under one or
+// more of these names:
+//
+// /usr/local/share/mime/globs2
+// /usr/share/mime/globs2
+// /etc/mime.types
+// /etc/apache2/mime.types
+// /etc/apache/mime.types
+// /etc/httpd/conf/mime.types
+//
+// On Windows, MIME types are extracted from the registry.
+//
+// Text types have the charset parameter set to "utf-8" by default.
+func TypeByExtension(ext string) string {
+ once.Do(initMime)
+
+ // Case-sensitive lookup.
+ if v, ok := mimeTypes.Load(ext); ok {
+ return v.(string)
+ }
+
+ // Case-insensitive lookup.
+ // Optimistically assume a short ASCII extension and be
+ // allocation-free in that case.
+ var buf [10]byte
+ lower := buf[:0]
+ const utf8RuneSelf = 0x80 // from utf8 package, but not importing it.
+ for i := 0; i < len(ext); i++ {
+ c := ext[i]
+ if c >= utf8RuneSelf {
+ // Slow path.
+ si, _ := mimeTypesLower.Load(strings.ToLower(ext))
+ s, _ := si.(string)
+ return s
+ }
+ if 'A' <= c && c <= 'Z' {
+ lower = append(lower, c+('a'-'A'))
+ } else {
+ lower = append(lower, c)
+ }
+ }
+ si, _ := mimeTypesLower.Load(string(lower))
+ s, _ := si.(string)
+ return s
+}
+
+// ExtensionsByType returns the extensions known to be associated with the MIME
+// type typ. The returned extensions will each begin with a leading dot, as in
+// ".html". When typ has no associated extensions, ExtensionsByType returns an
+// nil slice.
+//
+// The built-in table is small but on unix it is augmented by the local
+// system's MIME-info database or mime.types file(s) if available under one or
+// more of these names:
+//
+// /usr/local/share/mime/globs2
+// /usr/share/mime/globs2
+// /etc/mime.types
+// /etc/apache2/mime.types
+// /etc/apache/mime.types
+// /etc/httpd/conf/mime.types
+//
+// On Windows, extensions are extracted from the registry.
+func ExtensionsByType(typ string) ([]string, error) {
+ justType, _, err := ParseMediaType(typ)
+ if err != nil {
+ return nil, err
+ }
+
+ once.Do(initMime)
+ s, ok := extensions.Load(justType)
+ if !ok {
+ return nil, nil
+ }
+ ret := append([]string(nil), s.([]string)...)
+ slices.Sort(ret)
+ return ret, nil
+}
+
+// AddExtensionType sets the MIME type associated with
+// the extension ext to typ. The extension should begin with
+// a leading dot, as in ".html".
+func AddExtensionType(ext, typ string) error {
+ if !strings.HasPrefix(ext, ".") {
+ return fmt.Errorf("mime: extension %q missing leading dot", ext)
+ }
+ once.Do(initMime)
+ return setExtensionType(ext, typ)
+}
+
+func setExtensionType(extension, mimeType string) error {
+ justType, param, err := ParseMediaType(mimeType)
+ if err != nil {
+ return err
+ }
+ if strings.HasPrefix(mimeType, "text/") && param["charset"] == "" {
+ param["charset"] = "utf-8"
+ mimeType = FormatMediaType(mimeType, param)
+ }
+ extLower := strings.ToLower(extension)
+
+ mimeTypes.Store(extension, mimeType)
+ mimeTypesLower.Store(extLower, mimeType)
+
+ extensionsMu.Lock()
+ defer extensionsMu.Unlock()
+ var exts []string
+ if ei, ok := extensions.Load(justType); ok {
+ exts = ei.([]string)
+ }
+ for _, v := range exts {
+ if v == extLower {
+ return nil
+ }
+ }
+ extensions.Store(justType, append(exts, extLower))
+ return nil
+}
diff --git a/go/src/mime/type_dragonfly.go b/go/src/mime/type_dragonfly.go
new file mode 100644
index 0000000000000000000000000000000000000000..d09d74a9cce251236f2831a3ef71575fdd138c87
--- /dev/null
+++ b/go/src/mime/type_dragonfly.go
@@ -0,0 +1,9 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mime
+
+func init() {
+ typeFiles = append(typeFiles, "/usr/local/etc/mime.types")
+}
diff --git a/go/src/mime/type_freebsd.go b/go/src/mime/type_freebsd.go
new file mode 100644
index 0000000000000000000000000000000000000000..d09d74a9cce251236f2831a3ef71575fdd138c87
--- /dev/null
+++ b/go/src/mime/type_freebsd.go
@@ -0,0 +1,9 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mime
+
+func init() {
+ typeFiles = append(typeFiles, "/usr/local/etc/mime.types")
+}
diff --git a/go/src/mime/type_openbsd.go b/go/src/mime/type_openbsd.go
new file mode 100644
index 0000000000000000000000000000000000000000..c3b1abb99fc0a457373b9f01b8d45fc7e7251154
--- /dev/null
+++ b/go/src/mime/type_openbsd.go
@@ -0,0 +1,9 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mime
+
+func init() {
+ typeFiles = append(typeFiles, "/usr/share/misc/mime.types")
+}
diff --git a/go/src/mime/type_plan9.go b/go/src/mime/type_plan9.go
new file mode 100644
index 0000000000000000000000000000000000000000..14ff973405186392163ed42dd5db5b1d6e47fec7
--- /dev/null
+++ b/go/src/mime/type_plan9.go
@@ -0,0 +1,57 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mime
+
+import (
+ "bufio"
+ "os"
+ "strings"
+)
+
+func init() {
+ osInitMime = initMimePlan9
+}
+
+func initMimePlan9() {
+ for _, filename := range typeFiles {
+ loadMimeFile(filename)
+ }
+}
+
+var typeFiles = []string{
+ "/sys/lib/mimetype",
+}
+
+func initMimeForTests() map[string]string {
+ typeFiles = []string{"testdata/test.types.plan9"}
+ return map[string]string{
+ ".t1": "application/test",
+ ".t2": "text/test; charset=utf-8",
+ ".pNg": "image/png",
+ }
+}
+
+func loadMimeFile(filename string) {
+ f, err := os.Open(filename)
+ if err != nil {
+ return
+ }
+ defer f.Close()
+
+ scanner := bufio.NewScanner(f)
+ for scanner.Scan() {
+ fields := strings.Fields(scanner.Text())
+ if len(fields) <= 2 || fields[0][0] != '.' {
+ continue
+ }
+ if fields[1] == "-" || fields[2] == "-" {
+ continue
+ }
+ setExtensionType(fields[0], fields[1]+"/"+fields[2])
+ }
+ if err := scanner.Err(); err != nil {
+ panic(err)
+ }
+}
diff --git a/go/src/mime/type_test.go b/go/src/mime/type_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..f4ec8c8754e69fd373bc37f02e59a988b8b46a3f
--- /dev/null
+++ b/go/src/mime/type_test.go
@@ -0,0 +1,268 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mime
+
+import (
+ "internal/asan"
+ "slices"
+ "strings"
+ "sync"
+ "testing"
+)
+
+func setMimeInit(fn func()) (cleanup func()) {
+ once = sync.Once{}
+ testInitMime = fn
+ return func() {
+ testInitMime = nil
+ once = sync.Once{}
+ }
+}
+
+func clearMimeTypes() {
+ setMimeTypes(map[string]string{}, map[string]string{})
+}
+
+func setType(ext, typ string) {
+ if !strings.HasPrefix(ext, ".") {
+ panic("missing leading dot")
+ }
+ if err := setExtensionType(ext, typ); err != nil {
+ panic("bad test data: " + err.Error())
+ }
+}
+
+func TestTypeByExtension(t *testing.T) {
+ once = sync.Once{}
+ // initMimeForTests returns the platform-specific extension =>
+ // type tests. On Unix and Plan 9, this also tests the parsing
+ // of MIME text files (in testdata/*). On Windows, we test the
+ // real registry on the machine and assume that ".png" exists
+ // there, which empirically it always has, for all versions of
+ // Windows.
+ typeTests := initMimeForTests()
+
+ for ext, want := range typeTests {
+ val := TypeByExtension(ext)
+ if val != want {
+ t.Errorf("TypeByExtension(%q) = %q, want %q", ext, val, want)
+ }
+ }
+}
+
+func TestTypeByExtension_LocalData(t *testing.T) {
+ cleanup := setMimeInit(func() {
+ clearMimeTypes()
+ setType(".foo", "x/foo")
+ setType(".bar", "x/bar")
+ setType(".Bar", "x/bar; capital=1")
+ })
+ defer cleanup()
+
+ tests := map[string]string{
+ ".foo": "x/foo",
+ ".bar": "x/bar",
+ ".Bar": "x/bar; capital=1",
+ ".sdlkfjskdlfj": "",
+ ".t1": "", // testdata shouldn't be used
+ }
+
+ for ext, want := range tests {
+ val := TypeByExtension(ext)
+ if val != want {
+ t.Errorf("TypeByExtension(%q) = %q, want %q", ext, val, want)
+ }
+ }
+}
+
+func TestTypeByExtensionCase(t *testing.T) {
+ const custom = "test/test; charset=iso-8859-1"
+ const caps = "test/test; WAS=ALLCAPS"
+
+ cleanup := setMimeInit(func() {
+ clearMimeTypes()
+ setType(".TEST", caps)
+ setType(".tesT", custom)
+ })
+ defer cleanup()
+
+ // case-sensitive lookup
+ if got := TypeByExtension(".tesT"); got != custom {
+ t.Fatalf("for .tesT, got %q; want %q", got, custom)
+ }
+ if got := TypeByExtension(".TEST"); got != caps {
+ t.Fatalf("for .TEST, got %q; want %s", got, caps)
+ }
+
+ // case-insensitive
+ if got := TypeByExtension(".TesT"); got != custom {
+ t.Fatalf("for .TesT, got %q; want %q", got, custom)
+ }
+}
+
+func TestExtensionsByType(t *testing.T) {
+ cleanup := setMimeInit(func() {
+ clearMimeTypes()
+ setType(".gif", "image/gif")
+ setType(".a", "foo/letter")
+ setType(".b", "foo/letter")
+ setType(".B", "foo/letter")
+ setType(".PNG", "image/png")
+ })
+ defer cleanup()
+
+ tests := []struct {
+ typ string
+ want []string
+ wantErr string
+ }{
+ {typ: "image/gif", want: []string{".gif"}},
+ {typ: "image/png", want: []string{".png"}}, // lowercase
+ {typ: "foo/letter", want: []string{".a", ".b"}},
+ {typ: "x/unknown", want: nil},
+ }
+
+ for _, tt := range tests {
+ got, err := ExtensionsByType(tt.typ)
+ if err != nil && tt.wantErr != "" && strings.Contains(err.Error(), tt.wantErr) {
+ continue
+ }
+ if err != nil {
+ t.Errorf("ExtensionsByType(%q) error: %v", tt.typ, err)
+ continue
+ }
+ if tt.wantErr != "" {
+ t.Errorf("ExtensionsByType(%q) = %q, %v; want error substring %q", tt.typ, got, err, tt.wantErr)
+ continue
+ }
+ if !slices.Equal(got, tt.want) {
+ t.Errorf("ExtensionsByType(%q) = %q; want %q", tt.typ, got, tt.want)
+ }
+ }
+}
+
+func TestLookupMallocs(t *testing.T) {
+ if asan.Enabled {
+ t.Skip("test allocates more with -asan; see #70079")
+ }
+ n := testing.AllocsPerRun(10000, func() {
+ TypeByExtension(".html")
+ TypeByExtension(".HtML")
+ })
+ if n > 0 {
+ t.Errorf("allocs = %v; want 0", n)
+ }
+}
+
+func BenchmarkTypeByExtension(b *testing.B) {
+ initMime()
+ b.ResetTimer()
+
+ for _, ext := range []string{
+ ".html",
+ ".HTML",
+ ".unused",
+ } {
+ b.Run(ext, func(b *testing.B) {
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ TypeByExtension(ext)
+ }
+ })
+ })
+ }
+}
+
+func BenchmarkExtensionsByType(b *testing.B) {
+ initMime()
+ b.ResetTimer()
+
+ for _, typ := range []string{
+ "text/html",
+ "text/html; charset=utf-8",
+ "application/octet-stream",
+ } {
+ b.Run(typ, func(b *testing.B) {
+ b.RunParallel(func(pb *testing.PB) {
+ for pb.Next() {
+ if _, err := ExtensionsByType(typ); err != nil {
+ b.Fatal(err)
+ }
+ }
+ })
+ })
+ }
+}
+
+func TestExtensionsByType2(t *testing.T) {
+ cleanup := setMimeInit(func() {
+ clearMimeTypes()
+ // Initialize built-in types like in type.go before osInitMime.
+ setMimeTypes(builtinTypesLower, builtinTypesLower)
+ })
+ defer cleanup()
+
+ tests := []struct {
+ typ string
+ want []string
+ }{
+ {typ: "application/postscript", want: []string{".ai", ".eps", ".ps"}},
+ {typ: "application/vnd.android.package-archive", want: []string{".apk"}},
+ {typ: "image/apng", want: []string{".apng"}},
+ {typ: "image/avif", want: []string{".avif"}},
+ {typ: "application/octet-stream", want: []string{".bin", ".com", ".exe"}},
+ {typ: "image/bmp", want: []string{".bmp"}},
+ {typ: "text/css; charset=utf-8", want: []string{".css"}},
+ {typ: "text/csv; charset=utf-8", want: []string{".csv"}},
+ {typ: "application/msword", want: []string{".doc"}},
+ {typ: "application/vnd.openxmlformats-officedocument.wordprocessingml.document", want: []string{".docx"}},
+ {typ: "text/html; charset=utf-8", want: []string{".ehtml", ".htm", ".html", ".shtml"}},
+ {typ: "message/rfc822", want: []string{".eml"}},
+ {typ: "audio/flac", want: []string{".flac"}},
+ {typ: "image/gif", want: []string{".gif"}},
+ {typ: "application/gzip", want: []string{".gz"}},
+ {typ: "image/vnd.microsoft.icon", want: []string{".ico"}},
+ {typ: "text/calendar; charset=utf-8", want: []string{".ics"}},
+ {typ: "image/jpeg", want: []string{".jfif", ".jpeg", ".jpg", ".pjp", ".pjpeg"}},
+ {typ: "text/javascript; charset=utf-8", want: []string{".js", ".mjs"}},
+ {typ: "application/json", want: []string{".json"}},
+ {typ: "audio/mp4", want: []string{".m4a"}},
+ {typ: "audio/mpeg", want: []string{".mp3"}},
+ {typ: "video/mp4", want: []string{".mp4"}},
+ {typ: "audio/ogg", want: []string{".oga", ".ogg", ".opus"}},
+ {typ: "video/ogg", want: []string{".ogv"}},
+ {typ: "application/pdf", want: []string{".pdf"}},
+ {typ: "image/png", want: []string{".png"}},
+ {typ: "application/vnd.ms-powerpoint", want: []string{".ppt"}},
+ {typ: "application/vnd.openxmlformats-officedocument.presentationml.presentation", want: []string{".pptx"}},
+ {typ: "application/rdf+xml", want: []string{".rdf"}},
+ {typ: "application/rtf", want: []string{".rtf"}},
+ {typ: "image/svg+xml", want: []string{".svg"}},
+ {typ: "text/plain; charset=utf-8", want: []string{".text", ".txt"}},
+ {typ: "image/tiff", want: []string{".tif", ".tiff"}},
+ {typ: "text/vtt; charset=utf-8", want: []string{".vtt"}},
+ {typ: "application/wasm", want: []string{".wasm"}},
+ {typ: "audio/wav", want: []string{".wav"}},
+ {typ: "audio/webm", want: []string{".webm"}},
+ {typ: "image/webp", want: []string{".webp"}},
+ {typ: "text/xml; charset=utf-8", want: []string{".xbl", ".xml", ".xsl"}},
+ {typ: "image/x-xbitmap", want: []string{".xbm"}},
+ {typ: "application/xhtml+xml", want: []string{".xht", ".xhtml"}},
+ {typ: "application/vnd.ms-excel", want: []string{".xls"}},
+ {typ: "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet", want: []string{".xlsx"}},
+ {typ: "application/zip", want: []string{".zip"}},
+ }
+
+ for _, tt := range tests {
+ got, err := ExtensionsByType(tt.typ)
+ if err != nil {
+ t.Errorf("ExtensionsByType(%q): %v", tt.typ, err)
+ continue
+ }
+ if !slices.Equal(got, tt.want) {
+ t.Errorf("ExtensionsByType(%q) = %q; want %q", tt.typ, got, tt.want)
+ }
+ }
+}
diff --git a/go/src/mime/type_unix.go b/go/src/mime/type_unix.go
new file mode 100644
index 0000000000000000000000000000000000000000..90414c1a18d06fa745be402f66b731a61923e4a1
--- /dev/null
+++ b/go/src/mime/type_unix.go
@@ -0,0 +1,126 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm) || wasip1
+
+package mime
+
+import (
+ "bufio"
+ "os"
+ "strings"
+)
+
+func init() {
+ osInitMime = initMimeUnix
+}
+
+// See https://specifications.freedesktop.org/shared-mime-info-spec/shared-mime-info-spec-0.21.html
+// for the FreeDesktop Shared MIME-info Database specification.
+var mimeGlobs = []string{
+ "/usr/local/share/mime/globs2",
+ "/usr/share/mime/globs2",
+}
+
+// Common locations for mime.types files on unix.
+var typeFiles = []string{
+ "/etc/mime.types",
+ "/etc/apache2/mime.types",
+ "/etc/apache/mime.types",
+ "/etc/httpd/conf/mime.types",
+}
+
+func loadMimeGlobsFile(filename string) error {
+ f, err := os.Open(filename)
+ if err != nil {
+ return err
+ }
+ defer f.Close()
+
+ scanner := bufio.NewScanner(f)
+ for scanner.Scan() {
+ // Each line should be of format: weight:mimetype:glob[:morefields...]
+ fields := strings.Split(scanner.Text(), ":")
+ if len(fields) < 3 || len(fields[0]) < 1 || len(fields[2]) < 3 {
+ continue
+ } else if fields[0][0] == '#' || fields[2][0] != '*' || fields[2][1] != '.' {
+ continue
+ }
+
+ extension := fields[2][1:]
+ if strings.ContainsAny(extension, "?*[") {
+ // Not a bare extension, but a glob. Ignore for now:
+ // - we do not have an implementation for this glob
+ // syntax (translation to path/filepath.Match could
+ // be possible)
+ // - support for globs with weight ordering would have
+ // performance impact to all lookups to support the
+ // rarely seen glob entries
+ // - trying to match glob metacharacters literally is
+ // not useful
+ continue
+ }
+ if _, ok := mimeTypes.Load(extension); ok {
+ // We've already seen this extension.
+ // The file is in weight order, so we keep
+ // the first entry that we see.
+ continue
+ }
+
+ setExtensionType(extension, fields[1])
+ }
+ if err := scanner.Err(); err != nil {
+ panic(err)
+ }
+ return nil
+}
+
+func loadMimeFile(filename string) {
+ f, err := os.Open(filename)
+ if err != nil {
+ return
+ }
+ defer f.Close()
+
+ scanner := bufio.NewScanner(f)
+ for scanner.Scan() {
+ fields := strings.Fields(scanner.Text())
+ if len(fields) <= 1 || fields[0][0] == '#' {
+ continue
+ }
+ mimeType := fields[0]
+ for _, ext := range fields[1:] {
+ if ext[0] == '#' {
+ break
+ }
+ setExtensionType("."+ext, mimeType)
+ }
+ }
+ if err := scanner.Err(); err != nil {
+ panic(err)
+ }
+}
+
+func initMimeUnix() {
+ for _, filename := range mimeGlobs {
+ if err := loadMimeGlobsFile(filename); err == nil {
+ return // Stop checking more files if mimetype database is found.
+ }
+ }
+
+ // Fallback if no system-generated mimetype database exists.
+ for _, filename := range typeFiles {
+ loadMimeFile(filename)
+ }
+}
+
+func initMimeForTests() map[string]string {
+ mimeGlobs = []string{""}
+ typeFiles = []string{"testdata/test.types"}
+ return map[string]string{
+ ".T1": "application/test",
+ ".t2": "text/test; charset=utf-8",
+ ".png": "image/png",
+ }
+}
diff --git a/go/src/mime/type_unix_test.go b/go/src/mime/type_unix_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..7b8db79d272a986b3a0df156a5489187d0fabf80
--- /dev/null
+++ b/go/src/mime/type_unix_test.go
@@ -0,0 +1,44 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || (js && wasm)
+
+package mime
+
+import (
+ "testing"
+)
+
+func initMimeUnixTest(t *testing.T) {
+ once.Do(initMime)
+ err := loadMimeGlobsFile("testdata/test.types.globs2")
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ loadMimeFile("testdata/test.types")
+}
+
+func TestTypeByExtensionUNIX(t *testing.T) {
+ initMimeUnixTest(t)
+ typeTests := map[string]string{
+ ".T1": "application/test",
+ ".t2": "text/test; charset=utf-8",
+ ".t3": "document/test",
+ ".t4": "example/test",
+ ".png": "image/png",
+ ",v": "",
+ "~": "",
+ ".foo?ar": "",
+ ".foo*r": "",
+ ".foo[1-3]": "",
+ }
+
+ for ext, want := range typeTests {
+ val := TypeByExtension(ext)
+ if val != want {
+ t.Errorf("TypeByExtension(%q) = %q, want %q", ext, val, want)
+ }
+ }
+}
diff --git a/go/src/mime/type_windows.go b/go/src/mime/type_windows.go
new file mode 100644
index 0000000000000000000000000000000000000000..93802141c532d0f79daeecd356d022a89cbd6167
--- /dev/null
+++ b/go/src/mime/type_windows.go
@@ -0,0 +1,52 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mime
+
+import (
+ "internal/syscall/windows/registry"
+)
+
+func init() {
+ osInitMime = initMimeWindows
+}
+
+func initMimeWindows() {
+ names, err := registry.CLASSES_ROOT.ReadSubKeyNames()
+ if err != nil {
+ return
+ }
+ for _, name := range names {
+ if len(name) < 2 || name[0] != '.' { // looking for extensions only
+ continue
+ }
+ k, err := registry.OpenKey(registry.CLASSES_ROOT, name, registry.READ)
+ if err != nil {
+ continue
+ }
+ v, _, err := k.GetStringValue("Content Type")
+ k.Close()
+ if err != nil {
+ continue
+ }
+
+ // There is a long-standing problem on Windows: the
+ // registry sometimes records that the ".js" extension
+ // should be "text/plain". See issue #32350. While
+ // normally local configuration should override
+ // defaults, this problem is common enough that we
+ // handle it here by ignoring that registry setting.
+ if name == ".js" && (v == "text/plain" || v == "text/plain; charset=utf-8") {
+ continue
+ }
+
+ setExtensionType(name, v)
+ }
+}
+
+func initMimeForTests() map[string]string {
+ return map[string]string{
+ ".PnG": "image/png",
+ }
+}
diff --git a/go/src/net/addrselect.go b/go/src/net/addrselect.go
new file mode 100644
index 0000000000000000000000000000000000000000..0ff8ec37c8de35cdfa2cb2b7c8dbc5f99d233dba
--- /dev/null
+++ b/go/src/net/addrselect.go
@@ -0,0 +1,368 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Minimal RFC 6724 address selection.
+
+package net
+
+import (
+ "net/netip"
+ "slices"
+)
+
+func sortByRFC6724(addrs []IPAddr) {
+ if len(addrs) < 2 {
+ return
+ }
+ sortByRFC6724withSrcs(addrs, srcAddrs(addrs))
+}
+
+func sortByRFC6724withSrcs(addrs []IPAddr, srcs []netip.Addr) {
+ if len(addrs) != len(srcs) {
+ panic("internal error")
+ }
+ addrInfos := make([]byRFC6724Info, len(addrs))
+ for i, v := range addrs {
+ addrAttrIP, _ := netip.AddrFromSlice(v.IP)
+ addrInfos[i] = byRFC6724Info{
+ addr: addrs[i],
+ addrAttr: ipAttrOf(addrAttrIP),
+ src: srcs[i],
+ srcAttr: ipAttrOf(srcs[i]),
+ }
+ }
+ slices.SortStableFunc(addrInfos, compareByRFC6724)
+ for i := range addrInfos {
+ addrs[i] = addrInfos[i].addr
+ }
+}
+
+// srcAddrs tries to UDP-connect to each address to see if it has a
+// route. (This doesn't send any packets). The destination port
+// number is irrelevant.
+func srcAddrs(addrs []IPAddr) []netip.Addr {
+ srcs := make([]netip.Addr, len(addrs))
+ dst := UDPAddr{Port: 53}
+ for i := range addrs {
+ dst.IP = addrs[i].IP
+ dst.Zone = addrs[i].Zone
+ c, err := DialUDP("udp", nil, &dst)
+ if err == nil {
+ if src, ok := c.LocalAddr().(*UDPAddr); ok {
+ srcs[i], _ = netip.AddrFromSlice(src.IP)
+ }
+ c.Close()
+ }
+ }
+ return srcs
+}
+
+type ipAttr struct {
+ Scope scope
+ Precedence uint8
+ Label uint8
+}
+
+func ipAttrOf(ip netip.Addr) ipAttr {
+ if !ip.IsValid() {
+ return ipAttr{}
+ }
+ match := rfc6724policyTable.Classify(ip)
+ return ipAttr{
+ Scope: classifyScope(ip),
+ Precedence: match.Precedence,
+ Label: match.Label,
+ }
+}
+
+type byRFC6724Info struct {
+ addr IPAddr
+ addrAttr ipAttr
+ src netip.Addr
+ srcAttr ipAttr
+}
+
+// compareByRFC6724 compares two byRFC6724Info records and returns an integer
+// indicating the order. It follows the algorithm and variable names from
+// RFC 6724 section 6. Returns -1 if a is preferred, 1 if b is preferred,
+// and 0 if they are equal.
+func compareByRFC6724(a, b byRFC6724Info) int {
+ DA := a.addr.IP
+ DB := b.addr.IP
+ SourceDA := a.src
+ SourceDB := b.src
+ attrDA := &a.addrAttr
+ attrDB := &b.addrAttr
+ attrSourceDA := &a.srcAttr
+ attrSourceDB := &b.srcAttr
+
+ const preferDA = -1
+ const preferDB = 1
+
+ // Rule 1: Avoid unusable destinations.
+ // If DB is known to be unreachable or if Source(DB) is undefined, then
+ // prefer DA. Similarly, if DA is known to be unreachable or if
+ // Source(DA) is undefined, then prefer DB.
+ if !SourceDA.IsValid() && !SourceDB.IsValid() {
+ return 0 // "equal"
+ }
+ if !SourceDB.IsValid() {
+ return preferDA
+ }
+ if !SourceDA.IsValid() {
+ return preferDB
+ }
+
+ // Rule 2: Prefer matching scope.
+ // If Scope(DA) = Scope(Source(DA)) and Scope(DB) <> Scope(Source(DB)),
+ // then prefer DA. Similarly, if Scope(DA) <> Scope(Source(DA)) and
+ // Scope(DB) = Scope(Source(DB)), then prefer DB.
+ if attrDA.Scope == attrSourceDA.Scope && attrDB.Scope != attrSourceDB.Scope {
+ return preferDA
+ }
+ if attrDA.Scope != attrSourceDA.Scope && attrDB.Scope == attrSourceDB.Scope {
+ return preferDB
+ }
+
+ // Rule 3: Avoid deprecated addresses.
+ // If Source(DA) is deprecated and Source(DB) is not, then prefer DB.
+ // Similarly, if Source(DA) is not deprecated and Source(DB) is
+ // deprecated, then prefer DA.
+
+ // TODO(bradfitz): implement? low priority for now.
+
+ // Rule 4: Prefer home addresses.
+ // If Source(DA) is simultaneously a home address and care-of address
+ // and Source(DB) is not, then prefer DA. Similarly, if Source(DB) is
+ // simultaneously a home address and care-of address and Source(DA) is
+ // not, then prefer DB.
+
+ // TODO(bradfitz): implement? low priority for now.
+
+ // Rule 5: Prefer matching label.
+ // If Label(Source(DA)) = Label(DA) and Label(Source(DB)) <> Label(DB),
+ // then prefer DA. Similarly, if Label(Source(DA)) <> Label(DA) and
+ // Label(Source(DB)) = Label(DB), then prefer DB.
+ if attrSourceDA.Label == attrDA.Label &&
+ attrSourceDB.Label != attrDB.Label {
+ return preferDA
+ }
+ if attrSourceDA.Label != attrDA.Label &&
+ attrSourceDB.Label == attrDB.Label {
+ return preferDB
+ }
+
+ // Rule 6: Prefer higher precedence.
+ // If Precedence(DA) > Precedence(DB), then prefer DA. Similarly, if
+ // Precedence(DA) < Precedence(DB), then prefer DB.
+ if attrDA.Precedence > attrDB.Precedence {
+ return preferDA
+ }
+ if attrDA.Precedence < attrDB.Precedence {
+ return preferDB
+ }
+
+ // Rule 7: Prefer native transport.
+ // If DA is reached via an encapsulating transition mechanism (e.g.,
+ // IPv6 in IPv4) and DB is not, then prefer DB. Similarly, if DB is
+ // reached via encapsulation and DA is not, then prefer DA.
+
+ // TODO(bradfitz): implement? low priority for now.
+
+ // Rule 8: Prefer smaller scope.
+ // If Scope(DA) < Scope(DB), then prefer DA. Similarly, if Scope(DA) >
+ // Scope(DB), then prefer DB.
+ if attrDA.Scope < attrDB.Scope {
+ return preferDA
+ }
+ if attrDA.Scope > attrDB.Scope {
+ return preferDB
+ }
+
+ // Rule 9: Use the longest matching prefix.
+ // When DA and DB belong to the same address family (both are IPv6 or
+ // both are IPv4 [but see below]): If CommonPrefixLen(Source(DA), DA) >
+ // CommonPrefixLen(Source(DB), DB), then prefer DA. Similarly, if
+ // CommonPrefixLen(Source(DA), DA) < CommonPrefixLen(Source(DB), DB),
+ // then prefer DB.
+ //
+ // However, applying this rule to IPv4 addresses causes
+ // problems (see issues 13283 and 18518), so limit to IPv6.
+ if DA.To4() == nil && DB.To4() == nil {
+ commonA := commonPrefixLen(SourceDA, DA)
+ commonB := commonPrefixLen(SourceDB, DB)
+
+ if commonA > commonB {
+ return preferDA
+ }
+ if commonA < commonB {
+ return preferDB
+ }
+ }
+
+ // Rule 10: Otherwise, leave the order unchanged.
+ // If DA preceded DB in the original list, prefer DA.
+ // Otherwise, prefer DB.
+ return 0 // "equal"
+}
+
+type policyTableEntry struct {
+ Prefix netip.Prefix
+ Precedence uint8
+ Label uint8
+}
+
+type policyTable []policyTableEntry
+
+// RFC 6724 section 2.1.
+// Items are sorted by the size of their Prefix.Mask.Size,
+var rfc6724policyTable = policyTable{
+ {
+ // "::1/128"
+ Prefix: netip.PrefixFrom(netip.AddrFrom16([16]byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x01}), 128),
+ Precedence: 50,
+ Label: 0,
+ },
+ {
+ // "::ffff:0:0/96"
+ // IPv4-compatible, etc.
+ Prefix: netip.PrefixFrom(netip.AddrFrom16([16]byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xff, 0xff}), 96),
+ Precedence: 35,
+ Label: 4,
+ },
+ {
+ // "::/96"
+ Prefix: netip.PrefixFrom(netip.AddrFrom16([16]byte{}), 96),
+ Precedence: 1,
+ Label: 3,
+ },
+ {
+ // "2001::/32"
+ // Teredo
+ Prefix: netip.PrefixFrom(netip.AddrFrom16([16]byte{0x20, 0x01}), 32),
+ Precedence: 5,
+ Label: 5,
+ },
+ {
+ // "2002::/16"
+ // 6to4
+ Prefix: netip.PrefixFrom(netip.AddrFrom16([16]byte{0x20, 0x02}), 16),
+ Precedence: 30,
+ Label: 2,
+ },
+ {
+ // "3ffe::/16"
+ Prefix: netip.PrefixFrom(netip.AddrFrom16([16]byte{0x3f, 0xfe}), 16),
+ Precedence: 1,
+ Label: 12,
+ },
+ {
+ // "fec0::/10"
+ Prefix: netip.PrefixFrom(netip.AddrFrom16([16]byte{0xfe, 0xc0}), 10),
+ Precedence: 1,
+ Label: 11,
+ },
+ {
+ // "fc00::/7"
+ Prefix: netip.PrefixFrom(netip.AddrFrom16([16]byte{0xfc}), 7),
+ Precedence: 3,
+ Label: 13,
+ },
+ {
+ // "::/0"
+ Prefix: netip.PrefixFrom(netip.AddrFrom16([16]byte{}), 0),
+ Precedence: 40,
+ Label: 1,
+ },
+}
+
+// Classify returns the policyTableEntry of the entry with the longest
+// matching prefix that contains ip.
+// The table t must be sorted from largest mask size to smallest.
+func (t policyTable) Classify(ip netip.Addr) policyTableEntry {
+ // Prefix.Contains() will not match an IPv6 prefix for an IPv4 address.
+ if ip.Is4() {
+ ip = netip.AddrFrom16(ip.As16())
+ }
+ for _, ent := range t {
+ if ent.Prefix.Contains(ip) {
+ return ent
+ }
+ }
+ return policyTableEntry{}
+}
+
+// RFC 6724 section 3.1.
+type scope uint8
+
+const (
+ scopeInterfaceLocal scope = 0x1
+ scopeLinkLocal scope = 0x2
+ scopeAdminLocal scope = 0x4
+ scopeSiteLocal scope = 0x5
+ scopeOrgLocal scope = 0x8
+ scopeGlobal scope = 0xe
+)
+
+func classifyScope(ip netip.Addr) scope {
+ if ip.IsLoopback() || ip.IsLinkLocalUnicast() {
+ return scopeLinkLocal
+ }
+ ipv6 := ip.Is6() && !ip.Is4In6()
+ ipv6AsBytes := ip.As16()
+ if ipv6 && ip.IsMulticast() {
+ return scope(ipv6AsBytes[1] & 0xf)
+ }
+ // Site-local addresses are defined in RFC 3513 section 2.5.6
+ // (and deprecated in RFC 3879).
+ if ipv6 && ipv6AsBytes[0] == 0xfe && ipv6AsBytes[1]&0xc0 == 0xc0 {
+ return scopeSiteLocal
+ }
+ return scopeGlobal
+}
+
+// commonPrefixLen reports the length of the longest prefix (looking
+// at the most significant, or leftmost, bits) that the
+// two addresses have in common, up to the length of a's prefix (i.e.,
+// the portion of the address not including the interface ID).
+//
+// If a or b is an IPv4 address as an IPv6 address, the IPv4 addresses
+// are compared (with max common prefix length of 32).
+// If a and b are different IP versions, 0 is returned.
+//
+// See https://tools.ietf.org/html/rfc6724#section-2.2
+func commonPrefixLen(a netip.Addr, b IP) (cpl int) {
+ if b4 := b.To4(); b4 != nil {
+ b = b4
+ }
+ aAsSlice := a.AsSlice()
+ if len(aAsSlice) != len(b) {
+ return 0
+ }
+ // If IPv6, only up to the prefix (first 64 bits)
+ if len(aAsSlice) > 8 {
+ aAsSlice = aAsSlice[:8]
+ b = b[:8]
+ }
+ for len(aAsSlice) > 0 {
+ if aAsSlice[0] == b[0] {
+ cpl += 8
+ aAsSlice = aAsSlice[1:]
+ b = b[1:]
+ continue
+ }
+ bits := 8
+ ab, bb := aAsSlice[0], b[0]
+ for {
+ ab >>= 1
+ bb >>= 1
+ bits--
+ if ab == bb {
+ cpl += bits
+ return
+ }
+ }
+ }
+ return
+}
diff --git a/go/src/net/addrselect_test.go b/go/src/net/addrselect_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..7e8134d754447b2d97eef3b8e4e979a5f1a729d1
--- /dev/null
+++ b/go/src/net/addrselect_test.go
@@ -0,0 +1,312 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
+
+package net
+
+import (
+ "net/netip"
+ "reflect"
+ "testing"
+)
+
+func TestSortByRFC6724(t *testing.T) {
+ tests := []struct {
+ in []IPAddr
+ srcs []netip.Addr
+ want []IPAddr
+ reverse bool // also test it starting backwards
+ }{
+ // Examples from RFC 6724 section 10.2:
+
+ // Prefer matching scope.
+ {
+ in: []IPAddr{
+ {IP: ParseIP("2001:db8:1::1")},
+ {IP: ParseIP("198.51.100.121")},
+ },
+ srcs: []netip.Addr{
+ netip.MustParseAddr("2001:db8:1::2"),
+ netip.MustParseAddr("169.254.13.78"),
+ },
+ want: []IPAddr{
+ {IP: ParseIP("2001:db8:1::1")},
+ {IP: ParseIP("198.51.100.121")},
+ },
+ reverse: true,
+ },
+
+ // Prefer matching scope.
+ {
+ in: []IPAddr{
+ {IP: ParseIP("2001:db8:1::1")},
+ {IP: ParseIP("198.51.100.121")},
+ },
+ srcs: []netip.Addr{
+ netip.MustParseAddr("fe80::1"),
+ netip.MustParseAddr("198.51.100.117"),
+ },
+ want: []IPAddr{
+ {IP: ParseIP("198.51.100.121")},
+ {IP: ParseIP("2001:db8:1::1")},
+ },
+ reverse: true,
+ },
+
+ // Prefer higher precedence.
+ {
+ in: []IPAddr{
+ {IP: ParseIP("2001:db8:1::1")},
+ {IP: ParseIP("10.1.2.3")},
+ },
+ srcs: []netip.Addr{
+ netip.MustParseAddr("2001:db8:1::2"),
+ netip.MustParseAddr("10.1.2.4"),
+ },
+ want: []IPAddr{
+ {IP: ParseIP("2001:db8:1::1")},
+ {IP: ParseIP("10.1.2.3")},
+ },
+ reverse: true,
+ },
+
+ // Prefer smaller scope.
+ {
+ in: []IPAddr{
+ {IP: ParseIP("2001:db8:1::1")},
+ {IP: ParseIP("fe80::1")},
+ },
+ srcs: []netip.Addr{
+ netip.MustParseAddr("2001:db8:1::2"),
+ netip.MustParseAddr("fe80::2"),
+ },
+ want: []IPAddr{
+ {IP: ParseIP("fe80::1")},
+ {IP: ParseIP("2001:db8:1::1")},
+ },
+ reverse: true,
+ },
+
+ // Issue 13283. Having a 10/8 source address does not
+ // mean we should prefer 23/8 destination addresses.
+ {
+ in: []IPAddr{
+ {IP: ParseIP("54.83.193.112")},
+ {IP: ParseIP("184.72.238.214")},
+ {IP: ParseIP("23.23.172.185")},
+ {IP: ParseIP("75.101.148.21")},
+ {IP: ParseIP("23.23.134.56")},
+ {IP: ParseIP("23.21.50.150")},
+ },
+ srcs: []netip.Addr{
+ netip.MustParseAddr("10.2.3.4"),
+ netip.MustParseAddr("10.2.3.4"),
+ netip.MustParseAddr("10.2.3.4"),
+ netip.MustParseAddr("10.2.3.4"),
+ netip.MustParseAddr("10.2.3.4"),
+ netip.MustParseAddr("10.2.3.4"),
+ },
+ want: []IPAddr{
+ {IP: ParseIP("54.83.193.112")},
+ {IP: ParseIP("184.72.238.214")},
+ {IP: ParseIP("23.23.172.185")},
+ {IP: ParseIP("75.101.148.21")},
+ {IP: ParseIP("23.23.134.56")},
+ {IP: ParseIP("23.21.50.150")},
+ },
+ reverse: false,
+ },
+ }
+ for i, tt := range tests {
+ inCopy := make([]IPAddr, len(tt.in))
+ copy(inCopy, tt.in)
+ srcCopy := make([]netip.Addr, len(tt.in))
+ copy(srcCopy, tt.srcs)
+ sortByRFC6724withSrcs(inCopy, srcCopy)
+ if !reflect.DeepEqual(inCopy, tt.want) {
+ t.Errorf("test %d:\nin = %s\ngot: %s\nwant: %s\n", i, tt.in, inCopy, tt.want)
+ }
+ if tt.reverse {
+ copy(inCopy, tt.in)
+ copy(srcCopy, tt.srcs)
+ for j := 0; j < len(inCopy)/2; j++ {
+ k := len(inCopy) - j - 1
+ inCopy[j], inCopy[k] = inCopy[k], inCopy[j]
+ srcCopy[j], srcCopy[k] = srcCopy[k], srcCopy[j]
+ }
+ sortByRFC6724withSrcs(inCopy, srcCopy)
+ if !reflect.DeepEqual(inCopy, tt.want) {
+ t.Errorf("test %d, starting backwards:\nin = %s\ngot: %s\nwant: %s\n", i, tt.in, inCopy, tt.want)
+ }
+ }
+
+ }
+
+}
+
+func TestRFC6724PolicyTableOrder(t *testing.T) {
+ for i := 0; i < len(rfc6724policyTable)-1; i++ {
+ if !(rfc6724policyTable[i].Prefix.Bits() >= rfc6724policyTable[i+1].Prefix.Bits()) {
+ t.Errorf("rfc6724policyTable item number %d sorted in wrong order = %d bits, next item = %d bits;", i, rfc6724policyTable[i].Prefix.Bits(), rfc6724policyTable[i+1].Prefix.Bits())
+ }
+ }
+}
+
+func TestRFC6724PolicyTableContent(t *testing.T) {
+ expectedRfc6724policyTable := policyTable{
+ {
+ Prefix: netip.MustParsePrefix("::1/128"),
+ Precedence: 50,
+ Label: 0,
+ },
+ {
+ Prefix: netip.MustParsePrefix("::ffff:0:0/96"),
+ Precedence: 35,
+ Label: 4,
+ },
+ {
+ Prefix: netip.MustParsePrefix("::/96"),
+ Precedence: 1,
+ Label: 3,
+ },
+ {
+ Prefix: netip.MustParsePrefix("2001::/32"),
+ Precedence: 5,
+ Label: 5,
+ },
+ {
+ Prefix: netip.MustParsePrefix("2002::/16"),
+ Precedence: 30,
+ Label: 2,
+ },
+ {
+ Prefix: netip.MustParsePrefix("3ffe::/16"),
+ Precedence: 1,
+ Label: 12,
+ },
+ {
+ Prefix: netip.MustParsePrefix("fec0::/10"),
+ Precedence: 1,
+ Label: 11,
+ },
+ {
+ Prefix: netip.MustParsePrefix("fc00::/7"),
+ Precedence: 3,
+ Label: 13,
+ },
+ {
+ Prefix: netip.MustParsePrefix("::/0"),
+ Precedence: 40,
+ Label: 1,
+ },
+ }
+ if !reflect.DeepEqual(rfc6724policyTable, expectedRfc6724policyTable) {
+ t.Errorf("rfc6724policyTable has wrong contend = %v; want %v", rfc6724policyTable, expectedRfc6724policyTable)
+ }
+}
+
+func TestRFC6724PolicyTableClassify(t *testing.T) {
+ tests := []struct {
+ ip netip.Addr
+ want policyTableEntry
+ }{
+ {
+ ip: netip.MustParseAddr("127.0.0.1"),
+ want: policyTableEntry{
+ Prefix: netip.MustParsePrefix("::ffff:0:0/96"),
+ Precedence: 35,
+ Label: 4,
+ },
+ },
+ {
+ ip: netip.MustParseAddr("2601:645:8002:a500:986f:1db8:c836:bd65"),
+ want: policyTableEntry{
+ Prefix: netip.MustParsePrefix("::/0"),
+ Precedence: 40,
+ Label: 1,
+ },
+ },
+ {
+ ip: netip.MustParseAddr("::1"),
+ want: policyTableEntry{
+ Prefix: netip.MustParsePrefix("::1/128"),
+ Precedence: 50,
+ Label: 0,
+ },
+ },
+ {
+ ip: netip.MustParseAddr("2002::ab12"),
+ want: policyTableEntry{
+ Prefix: netip.MustParsePrefix("2002::/16"),
+ Precedence: 30,
+ Label: 2,
+ },
+ },
+ }
+ for i, tt := range tests {
+ got := rfc6724policyTable.Classify(tt.ip)
+ if !reflect.DeepEqual(got, tt.want) {
+ t.Errorf("%d. Classify(%s) = %v; want %v", i, tt.ip, got, tt.want)
+ }
+ }
+}
+
+func TestRFC6724ClassifyScope(t *testing.T) {
+ tests := []struct {
+ ip netip.Addr
+ want scope
+ }{
+ {netip.MustParseAddr("127.0.0.1"), scopeLinkLocal}, // rfc6724#section-3.2
+ {netip.MustParseAddr("::1"), scopeLinkLocal}, // rfc4007#section-4
+ {netip.MustParseAddr("169.254.1.2"), scopeLinkLocal}, // rfc6724#section-3.2
+ {netip.MustParseAddr("fec0::1"), scopeSiteLocal},
+ {netip.MustParseAddr("8.8.8.8"), scopeGlobal},
+
+ {netip.MustParseAddr("ff02::"), scopeLinkLocal}, // IPv6 multicast
+ {netip.MustParseAddr("ff05::"), scopeSiteLocal}, // IPv6 multicast
+ {netip.MustParseAddr("ff04::"), scopeAdminLocal}, // IPv6 multicast
+ {netip.MustParseAddr("ff0e::"), scopeGlobal}, // IPv6 multicast
+
+ {netip.AddrFrom16([16]byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xe0, 0, 0, 0}), scopeGlobal}, // IPv4 link-local multicast as 16 bytes
+ {netip.AddrFrom16([16]byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xe0, 2, 2, 2}), scopeGlobal}, // IPv4 global multicast as 16 bytes
+ {netip.AddrFrom4([4]byte{0xe0, 0, 0, 0}), scopeGlobal}, // IPv4 link-local multicast as 4 bytes
+ {netip.AddrFrom4([4]byte{0xe0, 2, 2, 2}), scopeGlobal}, // IPv4 global multicast as 4 bytes
+ }
+ for i, tt := range tests {
+ got := classifyScope(tt.ip)
+ if got != tt.want {
+ t.Errorf("%d. classifyScope(%s) = %x; want %x", i, tt.ip, got, tt.want)
+ }
+ }
+}
+
+func TestRFC6724CommonPrefixLength(t *testing.T) {
+ tests := []struct {
+ a netip.Addr
+ b IP
+ want int
+ }{
+ {netip.MustParseAddr("fe80::1"), ParseIP("fe80::2"), 64},
+ {netip.MustParseAddr("fe81::1"), ParseIP("fe80::2"), 15},
+ {netip.MustParseAddr("127.0.0.1"), ParseIP("fe80::1"), 0}, // diff size
+ {netip.AddrFrom4([4]byte{1, 2, 3, 4}), IP{1, 2, 3, 4}, 32},
+ {netip.AddrFrom4([4]byte{1, 2, 255, 255}), IP{1, 2, 0, 0}, 16},
+ {netip.AddrFrom4([4]byte{1, 2, 127, 255}), IP{1, 2, 0, 0}, 17},
+ {netip.AddrFrom4([4]byte{1, 2, 63, 255}), IP{1, 2, 0, 0}, 18},
+ {netip.AddrFrom4([4]byte{1, 2, 31, 255}), IP{1, 2, 0, 0}, 19},
+ {netip.AddrFrom4([4]byte{1, 2, 15, 255}), IP{1, 2, 0, 0}, 20},
+ {netip.AddrFrom4([4]byte{1, 2, 7, 255}), IP{1, 2, 0, 0}, 21},
+ {netip.AddrFrom4([4]byte{1, 2, 3, 255}), IP{1, 2, 0, 0}, 22},
+ {netip.AddrFrom4([4]byte{1, 2, 1, 255}), IP{1, 2, 0, 0}, 23},
+ {netip.AddrFrom4([4]byte{1, 2, 0, 255}), IP{1, 2, 0, 0}, 24},
+ }
+ for i, tt := range tests {
+ got := commonPrefixLen(tt.a, tt.b)
+ if got != tt.want {
+ t.Errorf("%d. commonPrefixLen(%s, %s) = %d; want %d", i, tt.a, tt.b, got, tt.want)
+ }
+ }
+
+}
diff --git a/go/src/net/cgo_aix.go b/go/src/net/cgo_aix.go
new file mode 100644
index 0000000000000000000000000000000000000000..f3478148b4f60e352dec179b9c5e8304c446f6e2
--- /dev/null
+++ b/go/src/net/cgo_aix.go
@@ -0,0 +1,24 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build cgo && !netgo
+
+package net
+
+/*
+#include
+#include
+
+#include
+*/
+import "C"
+
+import "unsafe"
+
+const cgoAddrInfoFlags = C.AI_CANONNAME
+
+func cgoNameinfoPTR(b []byte, sa *C.struct_sockaddr, salen C.socklen_t) (int, error) {
+ gerrno, err := C.getnameinfo(sa, C.size_t(salen), (*C.char)(unsafe.Pointer(&b[0])), C.size_t(len(b)), nil, 0, C.NI_NAMEREQD)
+ return int(gerrno), err
+}
diff --git a/go/src/net/cgo_android.go b/go/src/net/cgo_android.go
new file mode 100644
index 0000000000000000000000000000000000000000..5ab8b5fedea13aacbdc9bb0758c5e4b9da232b73
--- /dev/null
+++ b/go/src/net/cgo_android.go
@@ -0,0 +1,12 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build cgo && !netgo
+
+package net
+
+//#include
+import "C"
+
+const cgoAddrInfoFlags = C.AI_CANONNAME
diff --git a/go/src/net/cgo_bsd.go b/go/src/net/cgo_bsd.go
new file mode 100644
index 0000000000000000000000000000000000000000..082e91faa8afb737bbbe92f95202872d560939da
--- /dev/null
+++ b/go/src/net/cgo_bsd.go
@@ -0,0 +1,14 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build cgo && !netgo && (dragonfly || freebsd)
+
+package net
+
+/*
+#include
+*/
+import "C"
+
+const cgoAddrInfoFlags = (C.AI_CANONNAME | C.AI_V4MAPPED | C.AI_ALL) & C.AI_MASK
diff --git a/go/src/net/cgo_darwin.go b/go/src/net/cgo_darwin.go
new file mode 100644
index 0000000000000000000000000000000000000000..129dd937fe0778c48a656dc99390e5f0f3be2073
--- /dev/null
+++ b/go/src/net/cgo_darwin.go
@@ -0,0 +1,9 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import "internal/syscall/unix"
+
+const cgoAddrInfoFlags = (unix.AI_CANONNAME | unix.AI_V4MAPPED | unix.AI_ALL) & unix.AI_MASK
diff --git a/go/src/net/cgo_linux.go b/go/src/net/cgo_linux.go
new file mode 100644
index 0000000000000000000000000000000000000000..de6e87f17622df6a46a73c1b99ae2e21be6672c4
--- /dev/null
+++ b/go/src/net/cgo_linux.go
@@ -0,0 +1,20 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !android && cgo && !netgo
+
+package net
+
+/*
+#include
+*/
+import "C"
+
+// NOTE(rsc): In theory there are approximately balanced
+// arguments for and against including AI_ADDRCONFIG
+// in the flags (it includes IPv4 results only on IPv4 systems,
+// and similarly for IPv6), but in practice setting it causes
+// getaddrinfo to return the wrong canonical name on Linux.
+// So definitely leave it out.
+const cgoAddrInfoFlags = C.AI_CANONNAME | C.AI_V4MAPPED | C.AI_ALL
diff --git a/go/src/net/cgo_netbsd.go b/go/src/net/cgo_netbsd.go
new file mode 100644
index 0000000000000000000000000000000000000000..03392e8ff34c596a979e6b20469e8f636a4925c2
--- /dev/null
+++ b/go/src/net/cgo_netbsd.go
@@ -0,0 +1,14 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build cgo && !netgo
+
+package net
+
+/*
+#include
+*/
+import "C"
+
+const cgoAddrInfoFlags = C.AI_CANONNAME
diff --git a/go/src/net/cgo_openbsd.go b/go/src/net/cgo_openbsd.go
new file mode 100644
index 0000000000000000000000000000000000000000..03392e8ff34c596a979e6b20469e8f636a4925c2
--- /dev/null
+++ b/go/src/net/cgo_openbsd.go
@@ -0,0 +1,14 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build cgo && !netgo
+
+package net
+
+/*
+#include
+*/
+import "C"
+
+const cgoAddrInfoFlags = C.AI_CANONNAME
diff --git a/go/src/net/cgo_resnew.go b/go/src/net/cgo_resnew.go
new file mode 100644
index 0000000000000000000000000000000000000000..3f21c5c4c4fd5bb899cbe9a174b681c905f45c5a
--- /dev/null
+++ b/go/src/net/cgo_resnew.go
@@ -0,0 +1,22 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build cgo && !netgo && ((linux && !android) || netbsd || solaris)
+
+package net
+
+/*
+#include
+#include
+
+#include
+*/
+import "C"
+
+import "unsafe"
+
+func cgoNameinfoPTR(b []byte, sa *C.struct_sockaddr, salen C.socklen_t) (int, error) {
+ gerrno, err := C.getnameinfo(sa, salen, (*C.char)(unsafe.Pointer(&b[0])), C.socklen_t(len(b)), nil, 0, C.NI_NAMEREQD)
+ return int(gerrno), err
+}
diff --git a/go/src/net/cgo_resold.go b/go/src/net/cgo_resold.go
new file mode 100644
index 0000000000000000000000000000000000000000..37c75527f95c0dedf8b36792cc94fb22eb89abc9
--- /dev/null
+++ b/go/src/net/cgo_resold.go
@@ -0,0 +1,22 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build cgo && !netgo && (android || freebsd || dragonfly || openbsd)
+
+package net
+
+/*
+#include
+#include
+
+#include
+*/
+import "C"
+
+import "unsafe"
+
+func cgoNameinfoPTR(b []byte, sa *C.struct_sockaddr, salen C.socklen_t) (int, error) {
+ gerrno, err := C.getnameinfo(sa, salen, (*C.char)(unsafe.Pointer(&b[0])), C.size_t(len(b)), nil, 0, C.NI_NAMEREQD)
+ return int(gerrno), err
+}
diff --git a/go/src/net/cgo_socknew.go b/go/src/net/cgo_socknew.go
new file mode 100644
index 0000000000000000000000000000000000000000..fbb9e10f3401967f2018f477392fb8428f7df752
--- /dev/null
+++ b/go/src/net/cgo_socknew.go
@@ -0,0 +1,32 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build cgo && !netgo && (android || linux || solaris)
+
+package net
+
+/*
+#include
+#include
+
+#include
+*/
+import "C"
+
+import (
+ "syscall"
+ "unsafe"
+)
+
+func cgoSockaddrInet4(ip IP) *C.struct_sockaddr {
+ sa := syscall.RawSockaddrInet4{Family: syscall.AF_INET}
+ copy(sa.Addr[:], ip)
+ return (*C.struct_sockaddr)(unsafe.Pointer(&sa))
+}
+
+func cgoSockaddrInet6(ip IP, zone int) *C.struct_sockaddr {
+ sa := syscall.RawSockaddrInet6{Family: syscall.AF_INET6, Scope_id: uint32(zone)}
+ copy(sa.Addr[:], ip)
+ return (*C.struct_sockaddr)(unsafe.Pointer(&sa))
+}
diff --git a/go/src/net/cgo_sockold.go b/go/src/net/cgo_sockold.go
new file mode 100644
index 0000000000000000000000000000000000000000..d0a99e073d82c2b98c812b01969cba08761a1350
--- /dev/null
+++ b/go/src/net/cgo_sockold.go
@@ -0,0 +1,32 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build cgo && !netgo && (aix || dragonfly || freebsd || netbsd || openbsd)
+
+package net
+
+/*
+#include
+#include
+
+#include
+*/
+import "C"
+
+import (
+ "syscall"
+ "unsafe"
+)
+
+func cgoSockaddrInet4(ip IP) *C.struct_sockaddr {
+ sa := syscall.RawSockaddrInet4{Len: syscall.SizeofSockaddrInet4, Family: syscall.AF_INET}
+ copy(sa.Addr[:], ip)
+ return (*C.struct_sockaddr)(unsafe.Pointer(&sa))
+}
+
+func cgoSockaddrInet6(ip IP, zone int) *C.struct_sockaddr {
+ sa := syscall.RawSockaddrInet6{Len: syscall.SizeofSockaddrInet6, Family: syscall.AF_INET6, Scope_id: uint32(zone)}
+ copy(sa.Addr[:], ip)
+ return (*C.struct_sockaddr)(unsafe.Pointer(&sa))
+}
diff --git a/go/src/net/cgo_solaris.go b/go/src/net/cgo_solaris.go
new file mode 100644
index 0000000000000000000000000000000000000000..98a0e819565d3fb58fe5e7a4d7e6feda2c2ee9ee
--- /dev/null
+++ b/go/src/net/cgo_solaris.go
@@ -0,0 +1,15 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build cgo && !netgo
+
+package net
+
+/*
+#cgo LDFLAGS: -lsocket -lnsl
+#include
+*/
+import "C"
+
+const cgoAddrInfoFlags = C.AI_CANONNAME | C.AI_V4MAPPED | C.AI_ALL
diff --git a/go/src/net/cgo_stub.go b/go/src/net/cgo_stub.go
new file mode 100644
index 0000000000000000000000000000000000000000..640f5a4fd65a552a2503255a3117c8f02bde9339
--- /dev/null
+++ b/go/src/net/cgo_stub.go
@@ -0,0 +1,40 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file holds stub versions of the cgo functions called on Unix systems.
+// We build this file:
+// - if using the netgo build tag on a Unix system
+// - on a Unix system without the cgo resolver functions
+// (Darwin always provides the cgo functions, in cgo_unix_syscall.go)
+// - on wasip1, where cgo is never available
+
+//go:build (netgo && unix) || (unix && !cgo && !darwin) || js || wasip1
+
+package net
+
+import "context"
+
+// cgoAvailable set to false to indicate that the cgo resolver
+// is not available on this system.
+const cgoAvailable = false
+
+func cgoLookupHost(ctx context.Context, name string) (addrs []string, err error) {
+ panic("cgo stub: cgo not available")
+}
+
+func cgoLookupPort(ctx context.Context, network, service string) (port int, err error) {
+ panic("cgo stub: cgo not available")
+}
+
+func cgoLookupIP(ctx context.Context, network, name string) (addrs []IPAddr, err error) {
+ panic("cgo stub: cgo not available")
+}
+
+func cgoLookupCNAME(ctx context.Context, name string) (cname string, err error) {
+ panic("cgo stub: cgo not available")
+}
+
+func cgoLookupPTR(ctx context.Context, addr string) (ptrs []string, err error) {
+ panic("cgo stub: cgo not available")
+}
diff --git a/go/src/net/cgo_unix.go b/go/src/net/cgo_unix.go
new file mode 100644
index 0000000000000000000000000000000000000000..7d970cfeaba9e916ca503ede1de13eef15edf908
--- /dev/null
+++ b/go/src/net/cgo_unix.go
@@ -0,0 +1,381 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file is called cgo_unix.go, but to allow syscalls-to-libc-based
+// implementations to share the code, it does not use cgo directly.
+// Instead of C.foo it uses _C_foo, which is defined in either
+// cgo_unix_cgo.go or cgo_unix_syscall.go
+
+//go:build !netgo && ((cgo && unix) || darwin)
+
+package net
+
+import (
+ "context"
+ "errors"
+ "internal/bytealg"
+ "net/netip"
+ "runtime"
+ "syscall"
+ "unsafe"
+
+ "golang.org/x/net/dns/dnsmessage"
+)
+
+// cgoAvailable set to true to indicate that the cgo resolver
+// is available on this system.
+const cgoAvailable = true
+
+// An addrinfoErrno represents a getaddrinfo, getnameinfo-specific
+// error number. It's a signed number and a zero value is a non-error
+// by convention.
+type addrinfoErrno int
+
+func (eai addrinfoErrno) Error() string { return _C_gai_strerror(_C_int(eai)) }
+func (eai addrinfoErrno) Temporary() bool { return eai == _C_EAI_AGAIN }
+func (eai addrinfoErrno) Timeout() bool { return false }
+
+// isAddrinfoErrno is just for testing purposes.
+func (eai addrinfoErrno) isAddrinfoErrno() {}
+
+// doBlockingWithCtx executes a blocking function in a separate goroutine when the provided
+// context is cancellable. It is intended for use with calls that don't support context
+// cancellation (cgo, syscalls). blocking func may still be running after this function finishes.
+// For the duration of the execution of the blocking function, the thread is 'acquired' using [acquireThread],
+// blocking might not be executed when the context gets canceled early.
+func doBlockingWithCtx[T any](ctx context.Context, lookupName string, blocking func() (T, error)) (T, error) {
+ if err := acquireThread(ctx); err != nil {
+ var zero T
+ return zero, newDNSError(mapErr(err), lookupName, "")
+ }
+
+ if ctx.Done() == nil {
+ defer releaseThread()
+ return blocking()
+ }
+
+ type result struct {
+ res T
+ err error
+ }
+
+ res := make(chan result, 1)
+ go func() {
+ defer releaseThread()
+ var r result
+ r.res, r.err = blocking()
+ res <- r
+ }()
+
+ select {
+ case r := <-res:
+ return r.res, r.err
+ case <-ctx.Done():
+ var zero T
+ return zero, newDNSError(mapErr(ctx.Err()), lookupName, "")
+ }
+}
+
+func cgoLookupHost(ctx context.Context, name string) (hosts []string, err error) {
+ addrs, err := cgoLookupIP(ctx, "ip", name)
+ if err != nil {
+ return nil, err
+ }
+ for _, addr := range addrs {
+ hosts = append(hosts, addr.String())
+ }
+ return hosts, nil
+}
+
+func cgoLookupPort(ctx context.Context, network, service string) (port int, err error) {
+ var hints _C_struct_addrinfo
+ switch network {
+ case "ip": // no hints
+ case "tcp", "tcp4", "tcp6":
+ *_C_ai_socktype(&hints) = _C_SOCK_STREAM
+ *_C_ai_protocol(&hints) = _C_IPPROTO_TCP
+ case "udp", "udp4", "udp6":
+ *_C_ai_socktype(&hints) = _C_SOCK_DGRAM
+ *_C_ai_protocol(&hints) = _C_IPPROTO_UDP
+ default:
+ return 0, &DNSError{Err: "unknown network", Name: network + "/" + service}
+ }
+ switch ipVersion(network) {
+ case '4':
+ *_C_ai_family(&hints) = _C_AF_INET
+ case '6':
+ *_C_ai_family(&hints) = _C_AF_INET6
+ }
+
+ return doBlockingWithCtx(ctx, network+"/"+service, func() (int, error) {
+ return cgoLookupServicePort(&hints, network, service)
+ })
+}
+
+func cgoLookupServicePort(hints *_C_struct_addrinfo, network, service string) (port int, err error) {
+ cservice, err := syscall.ByteSliceFromString(service)
+ if err != nil {
+ return 0, &DNSError{Err: err.Error(), Name: network + "/" + service}
+ }
+ // Lowercase the C service name.
+ for i, b := range cservice[:len(service)] {
+ cservice[i] = lowerASCII(b)
+ }
+ var res *_C_struct_addrinfo
+ gerrno, err := _C_getaddrinfo(nil, (*_C_char)(unsafe.Pointer(&cservice[0])), hints, &res)
+ if gerrno != 0 {
+ switch gerrno {
+ case _C_EAI_SYSTEM:
+ if err == nil { // see golang.org/issue/6232
+ err = syscall.EMFILE
+ }
+ return 0, newDNSError(err, network+"/"+service, "")
+ case _C_EAI_SERVICE, _C_EAI_NONAME: // Darwin returns EAI_NONAME.
+ return 0, newDNSError(errUnknownPort, network+"/"+service, "")
+ default:
+ return 0, newDNSError(addrinfoErrno(gerrno), network+"/"+service, "")
+ }
+ }
+ defer _C_freeaddrinfo(res)
+
+ for r := res; r != nil; r = *_C_ai_next(r) {
+ switch *_C_ai_family(r) {
+ case _C_AF_INET:
+ sa := (*syscall.RawSockaddrInet4)(unsafe.Pointer(*_C_ai_addr(r)))
+ p := (*[2]byte)(unsafe.Pointer(&sa.Port))
+ return int(p[0])<<8 | int(p[1]), nil
+ case _C_AF_INET6:
+ sa := (*syscall.RawSockaddrInet6)(unsafe.Pointer(*_C_ai_addr(r)))
+ p := (*[2]byte)(unsafe.Pointer(&sa.Port))
+ return int(p[0])<<8 | int(p[1]), nil
+ }
+ }
+ return 0, newDNSError(errUnknownPort, network+"/"+service, "")
+}
+
+func cgoLookupHostIP(network, name string) (addrs []IPAddr, err error) {
+ var hints _C_struct_addrinfo
+ *_C_ai_flags(&hints) = cgoAddrInfoFlags
+ *_C_ai_socktype(&hints) = _C_SOCK_STREAM
+ *_C_ai_family(&hints) = _C_AF_UNSPEC
+ switch ipVersion(network) {
+ case '4':
+ *_C_ai_family(&hints) = _C_AF_INET
+ case '6':
+ *_C_ai_family(&hints) = _C_AF_INET6
+ }
+
+ h, err := syscall.BytePtrFromString(name)
+ if err != nil {
+ return nil, &DNSError{Err: err.Error(), Name: name}
+ }
+ var res *_C_struct_addrinfo
+ gerrno, err := _C_getaddrinfo((*_C_char)(unsafe.Pointer(h)), nil, &hints, &res)
+ if gerrno != 0 {
+ switch gerrno {
+ case _C_EAI_SYSTEM:
+ if err == nil {
+ // err should not be nil, but sometimes getaddrinfo returns
+ // gerrno == _C_EAI_SYSTEM with err == nil on Linux.
+ // The report claims that it happens when we have too many
+ // open files, so use syscall.EMFILE (too many open files in system).
+ // Most system calls would return ENFILE (too many open files),
+ // so at the least EMFILE should be easy to recognize if this
+ // comes up again. golang.org/issue/6232.
+ err = syscall.EMFILE
+ }
+ return nil, newDNSError(err, name, "")
+ case _C_EAI_NONAME, _C_EAI_NODATA:
+ return nil, newDNSError(errNoSuchHost, name, "")
+ case _C_EAI_ADDRFAMILY:
+ if runtime.GOOS == "freebsd" {
+ // FreeBSD began returning EAI_ADDRFAMILY for valid hosts without
+ // an A record in 13.2. We previously returned "no such host" for
+ // this case.
+ //
+ // https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=273912
+ return nil, newDNSError(errNoSuchHost, name, "")
+ }
+ fallthrough
+ default:
+ return nil, newDNSError(addrinfoErrno(gerrno), name, "")
+ }
+
+ }
+ defer _C_freeaddrinfo(res)
+
+ for r := res; r != nil; r = *_C_ai_next(r) {
+ // We only asked for SOCK_STREAM, but check anyhow.
+ if *_C_ai_socktype(r) != _C_SOCK_STREAM {
+ continue
+ }
+ switch *_C_ai_family(r) {
+ case _C_AF_INET:
+ sa := (*syscall.RawSockaddrInet4)(unsafe.Pointer(*_C_ai_addr(r)))
+ addr := IPAddr{IP: copyIP(sa.Addr[:])}
+ addrs = append(addrs, addr)
+ case _C_AF_INET6:
+ sa := (*syscall.RawSockaddrInet6)(unsafe.Pointer(*_C_ai_addr(r)))
+ addr := IPAddr{IP: copyIP(sa.Addr[:]), Zone: zoneCache.name(int(sa.Scope_id))}
+ addrs = append(addrs, addr)
+ }
+ }
+ return addrs, nil
+}
+
+func cgoLookupIP(ctx context.Context, network, name string) (addrs []IPAddr, err error) {
+ return doBlockingWithCtx(ctx, name, func() ([]IPAddr, error) {
+ return cgoLookupHostIP(network, name)
+ })
+}
+
+// These are roughly enough for the following:
+//
+// Source Encoding Maximum length of single name entry
+// Unicast DNS ASCII or <=253 + a NUL terminator
+// Unicode in RFC 5892 252 * total number of labels + delimiters + a NUL terminator
+// Multicast DNS UTF-8 in RFC 5198 or <=253 + a NUL terminator
+// the same as unicast DNS ASCII <=253 + a NUL terminator
+// Local database various depends on implementation
+const (
+ nameinfoLen = 64
+ maxNameinfoLen = 4096
+)
+
+func cgoLookupPTR(ctx context.Context, addr string) (names []string, err error) {
+ ip, err := netip.ParseAddr(addr)
+ if err != nil {
+ return nil, &DNSError{Err: "invalid address", Name: addr}
+ }
+ sa, salen := cgoSockaddr(IP(ip.AsSlice()), ip.Zone())
+ if sa == nil {
+ return nil, &DNSError{Err: "invalid address " + ip.String(), Name: addr}
+ }
+
+ return doBlockingWithCtx(ctx, addr, func() ([]string, error) {
+ return cgoLookupAddrPTR(addr, sa, salen)
+ })
+}
+
+func cgoLookupAddrPTR(addr string, sa *_C_struct_sockaddr, salen _C_socklen_t) (names []string, err error) {
+ var gerrno int
+ var b []byte
+ for l := nameinfoLen; l <= maxNameinfoLen; l *= 2 {
+ b = make([]byte, l)
+ gerrno, err = cgoNameinfoPTR(b, sa, salen)
+ if gerrno == 0 || gerrno != _C_EAI_OVERFLOW {
+ break
+ }
+ }
+ if gerrno != 0 {
+ switch gerrno {
+ case _C_EAI_SYSTEM:
+ if err == nil { // see golang.org/issue/6232
+ err = syscall.EMFILE
+ }
+ return nil, newDNSError(err, addr, "")
+ case _C_EAI_NONAME:
+ return nil, newDNSError(errNoSuchHost, addr, "")
+ default:
+ return nil, newDNSError(addrinfoErrno(gerrno), addr, "")
+ }
+ }
+ if i := bytealg.IndexByte(b, 0); i != -1 {
+ b = b[:i]
+ }
+ return []string{absDomainName(string(b))}, nil
+}
+
+func cgoSockaddr(ip IP, zone string) (*_C_struct_sockaddr, _C_socklen_t) {
+ if ip4 := ip.To4(); ip4 != nil {
+ return cgoSockaddrInet4(ip4), _C_socklen_t(syscall.SizeofSockaddrInet4)
+ }
+ if ip6 := ip.To16(); ip6 != nil {
+ return cgoSockaddrInet6(ip6, zoneCache.index(zone)), _C_socklen_t(syscall.SizeofSockaddrInet6)
+ }
+ return nil, 0
+}
+
+func cgoLookupCNAME(ctx context.Context, name string) (cname string, err error) {
+ resources, err := resSearch(ctx, name, int(dnsmessage.TypeCNAME), int(dnsmessage.ClassINET))
+ if err != nil {
+ return "", err
+ }
+ cname, err = parseCNAMEFromResources(resources)
+ if err != nil {
+ return "", err
+ }
+ return cname, nil
+}
+
+// resSearch will make a call to the 'res_nsearch' routine in the C library
+// and parse the output as a slice of DNS resources.
+func resSearch(ctx context.Context, hostname string, rtype, class int) ([]dnsmessage.Resource, error) {
+ return doBlockingWithCtx(ctx, hostname, func() ([]dnsmessage.Resource, error) {
+ return cgoResSearch(hostname, rtype, class)
+ })
+}
+
+func cgoResSearch(hostname string, rtype, class int) ([]dnsmessage.Resource, error) {
+ resStateSize := unsafe.Sizeof(_C_struct___res_state{})
+ var state *_C_struct___res_state
+ if resStateSize > 0 {
+ mem := _C_malloc(resStateSize)
+ defer _C_free(mem)
+ memSlice := unsafe.Slice((*byte)(mem), resStateSize)
+ clear(memSlice)
+ state = (*_C_struct___res_state)(unsafe.Pointer(&memSlice[0]))
+ }
+ if err := _C_res_ninit(state); err != nil {
+ return nil, errors.New("res_ninit failure: " + err.Error())
+ }
+ defer _C_res_nclose(state)
+
+ // Some res_nsearch implementations (like macOS) do not set errno.
+ // They set h_errno, which is not per-thread and useless to us.
+ // res_nsearch returns the size of the DNS response packet.
+ // But if the DNS response packet contains failure-like response codes,
+ // res_search returns -1 even though it has copied the packet into buf,
+ // giving us no way to find out how big the packet is.
+ // For now, we are willing to take res_search's word that there's nothing
+ // useful in the response, even though there *is* a response.
+ bufSize := maxDNSPacketSize
+ buf := (*_C_uchar)(_C_malloc(uintptr(bufSize)))
+ defer func() {
+ // Free in a closure which captures buf to pick up a reallocated buffer from below.
+ _C_free(unsafe.Pointer(buf))
+ }()
+
+ s, err := syscall.BytePtrFromString(hostname)
+ if err != nil {
+ return nil, err
+ }
+
+ var size int
+ for {
+ size = _C_res_nsearch(state, (*_C_char)(unsafe.Pointer(s)), class, rtype, buf, bufSize)
+ if size <= 0 || size > 0xffff {
+ return nil, errors.New("res_nsearch failure")
+ }
+ if size <= bufSize {
+ break
+ }
+
+ // Allocate a bigger buffer to fit the entire msg.
+ _C_free(unsafe.Pointer(buf))
+ bufSize = size
+ buf = (*_C_uchar)(_C_malloc(uintptr(bufSize)))
+ }
+
+ var p dnsmessage.Parser
+ if _, err := p.Start(unsafe.Slice((*byte)(unsafe.Pointer(buf)), size)); err != nil {
+ return nil, err
+ }
+ p.SkipAllQuestions()
+ resources, err := p.AllAnswers()
+ if err != nil {
+ return nil, err
+ }
+ return resources, nil
+}
diff --git a/go/src/net/cgo_unix_cgo.go b/go/src/net/cgo_unix_cgo.go
new file mode 100644
index 0000000000000000000000000000000000000000..c4b8197c620458fa9871ed872a5133730c668b79
--- /dev/null
+++ b/go/src/net/cgo_unix_cgo.go
@@ -0,0 +1,86 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build cgo && !netgo && unix && !darwin
+
+package net
+
+/*
+#define _GNU_SOURCE 1
+
+#cgo CFLAGS: -fno-stack-protector
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+
+#ifndef EAI_NODATA
+#define EAI_NODATA -5
+#endif
+
+// If nothing else defined EAI_ADDRFAMILY, make sure it has a value.
+#ifndef EAI_ADDRFAMILY
+#define EAI_ADDRFAMILY -9
+#endif
+
+// If nothing else defined EAI_OVERFLOW, make sure it has a value.
+#ifndef EAI_OVERFLOW
+#define EAI_OVERFLOW -12
+#endif
+*/
+import "C"
+import "unsafe"
+
+const (
+ _C_AF_INET = C.AF_INET
+ _C_AF_INET6 = C.AF_INET6
+ _C_AF_UNSPEC = C.AF_UNSPEC
+ _C_EAI_ADDRFAMILY = C.EAI_ADDRFAMILY
+ _C_EAI_AGAIN = C.EAI_AGAIN
+ _C_EAI_NODATA = C.EAI_NODATA
+ _C_EAI_NONAME = C.EAI_NONAME
+ _C_EAI_SERVICE = C.EAI_SERVICE
+ _C_EAI_OVERFLOW = C.EAI_OVERFLOW
+ _C_EAI_SYSTEM = C.EAI_SYSTEM
+ _C_IPPROTO_TCP = C.IPPROTO_TCP
+ _C_IPPROTO_UDP = C.IPPROTO_UDP
+ _C_SOCK_DGRAM = C.SOCK_DGRAM
+ _C_SOCK_STREAM = C.SOCK_STREAM
+)
+
+type (
+ _C_char = C.char
+ _C_uchar = C.uchar
+ _C_int = C.int
+ _C_uint = C.uint
+ _C_socklen_t = C.socklen_t
+ _C_struct_addrinfo = C.struct_addrinfo
+ _C_struct_sockaddr = C.struct_sockaddr
+)
+
+func _C_malloc(n uintptr) unsafe.Pointer { return C.malloc(C.size_t(n)) }
+func _C_free(p unsafe.Pointer) { C.free(p) }
+
+func _C_ai_addr(ai *_C_struct_addrinfo) **_C_struct_sockaddr { return &ai.ai_addr }
+func _C_ai_family(ai *_C_struct_addrinfo) *_C_int { return &ai.ai_family }
+func _C_ai_flags(ai *_C_struct_addrinfo) *_C_int { return &ai.ai_flags }
+func _C_ai_next(ai *_C_struct_addrinfo) **_C_struct_addrinfo { return &ai.ai_next }
+func _C_ai_protocol(ai *_C_struct_addrinfo) *_C_int { return &ai.ai_protocol }
+func _C_ai_socktype(ai *_C_struct_addrinfo) *_C_int { return &ai.ai_socktype }
+
+func _C_freeaddrinfo(ai *_C_struct_addrinfo) {
+ C.freeaddrinfo(ai)
+}
+
+func _C_gai_strerror(eai _C_int) string {
+ return C.GoString(C.gai_strerror(eai))
+}
+
+func _C_getaddrinfo(hostname, servname *_C_char, hints *_C_struct_addrinfo, res **_C_struct_addrinfo) (int, error) {
+ x, err := C.getaddrinfo(hostname, servname, hints, res)
+ return int(x), err
+}
diff --git a/go/src/net/cgo_unix_cgo_res.go b/go/src/net/cgo_unix_cgo_res.go
new file mode 100644
index 0000000000000000000000000000000000000000..c5f30238a13c8f0ce25f1b0656725ef04c00e965
--- /dev/null
+++ b/go/src/net/cgo_unix_cgo_res.go
@@ -0,0 +1,38 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// res_search, for cgo systems where that is thread-safe.
+
+//go:build cgo && !netgo && (linux || openbsd)
+
+package net
+
+/*
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+
+#cgo !android,!openbsd LDFLAGS: -lresolv
+*/
+import "C"
+
+type _C_struct___res_state = struct{}
+
+func _C_res_ninit(state *_C_struct___res_state) error {
+ return nil
+}
+
+func _C_res_nclose(state *_C_struct___res_state) {
+ return
+}
+
+func _C_res_nsearch(state *_C_struct___res_state, dname *_C_char, class, typ int, ans *_C_uchar, anslen int) int {
+ x := C.res_search(dname, C.int(class), C.int(typ), ans, C.int(anslen))
+ return int(x)
+}
diff --git a/go/src/net/cgo_unix_cgo_resn.go b/go/src/net/cgo_unix_cgo_resn.go
new file mode 100644
index 0000000000000000000000000000000000000000..4fc747b5a339079a086b85cc54f29b1b04e7b84f
--- /dev/null
+++ b/go/src/net/cgo_unix_cgo_resn.go
@@ -0,0 +1,39 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// res_nsearch, for cgo systems where that's available.
+
+//go:build cgo && !netgo && unix && !(darwin || linux || openbsd)
+
+package net
+
+/*
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+
+#cgo !aix,!dragonfly,!freebsd LDFLAGS: -lresolv
+*/
+import "C"
+
+type _C_struct___res_state = C.struct___res_state
+
+func _C_res_ninit(state *_C_struct___res_state) error {
+ _, err := C.res_ninit(state)
+ return err
+}
+
+func _C_res_nclose(state *_C_struct___res_state) {
+ C.res_nclose(state)
+}
+
+func _C_res_nsearch(state *_C_struct___res_state, dname *_C_char, class, typ int, ans *_C_uchar, anslen int) int {
+ x := C.res_nsearch(state, dname, C.int(class), C.int(typ), ans, C.int(anslen))
+ return int(x)
+}
diff --git a/go/src/net/cgo_unix_syscall.go b/go/src/net/cgo_unix_syscall.go
new file mode 100644
index 0000000000000000000000000000000000000000..6b7ef74bd2b94559b46a86a7fddf8691b2871538
--- /dev/null
+++ b/go/src/net/cgo_unix_syscall.go
@@ -0,0 +1,100 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !netgo && darwin
+
+package net
+
+import (
+ "internal/syscall/unix"
+ "runtime"
+ "syscall"
+ "unsafe"
+)
+
+const (
+ _C_AF_INET = syscall.AF_INET
+ _C_AF_INET6 = syscall.AF_INET6
+ _C_AF_UNSPEC = syscall.AF_UNSPEC
+ _C_EAI_ADDRFAMILY = unix.EAI_ADDRFAMILY
+ _C_EAI_AGAIN = unix.EAI_AGAIN
+ _C_EAI_NONAME = unix.EAI_NONAME
+ _C_EAI_SERVICE = unix.EAI_SERVICE
+ _C_EAI_NODATA = unix.EAI_NODATA
+ _C_EAI_OVERFLOW = unix.EAI_OVERFLOW
+ _C_EAI_SYSTEM = unix.EAI_SYSTEM
+ _C_IPPROTO_TCP = syscall.IPPROTO_TCP
+ _C_IPPROTO_UDP = syscall.IPPROTO_UDP
+ _C_SOCK_DGRAM = syscall.SOCK_DGRAM
+ _C_SOCK_STREAM = syscall.SOCK_STREAM
+)
+
+type (
+ _C_char = byte
+ _C_int = int32
+ _C_uchar = byte
+ _C_uint = uint32
+ _C_socklen_t = int
+ _C_struct___res_state = unix.ResState
+ _C_struct_addrinfo = unix.Addrinfo
+ _C_struct_sockaddr = syscall.RawSockaddr
+)
+
+func _C_free(p unsafe.Pointer) { runtime.KeepAlive(p) }
+
+func _C_malloc(n uintptr) unsafe.Pointer {
+ if n <= 0 {
+ n = 1
+ }
+ return unsafe.Pointer(&make([]byte, n)[0])
+}
+
+func _C_ai_addr(ai *_C_struct_addrinfo) **_C_struct_sockaddr { return &ai.Addr }
+func _C_ai_family(ai *_C_struct_addrinfo) *_C_int { return &ai.Family }
+func _C_ai_flags(ai *_C_struct_addrinfo) *_C_int { return &ai.Flags }
+func _C_ai_next(ai *_C_struct_addrinfo) **_C_struct_addrinfo { return &ai.Next }
+func _C_ai_protocol(ai *_C_struct_addrinfo) *_C_int { return &ai.Protocol }
+func _C_ai_socktype(ai *_C_struct_addrinfo) *_C_int { return &ai.Socktype }
+
+func _C_freeaddrinfo(ai *_C_struct_addrinfo) {
+ unix.Freeaddrinfo(ai)
+}
+
+func _C_gai_strerror(eai _C_int) string {
+ return unix.GaiStrerror(int(eai))
+}
+
+func _C_getaddrinfo(hostname, servname *byte, hints *_C_struct_addrinfo, res **_C_struct_addrinfo) (int, error) {
+ return unix.Getaddrinfo(hostname, servname, hints, res)
+}
+
+func _C_res_ninit(state *_C_struct___res_state) error {
+ unix.ResNinit(state)
+ return nil
+}
+
+func _C_res_nsearch(state *_C_struct___res_state, dname *_C_char, class, typ int, ans *_C_char, anslen int) int {
+ x, _ := unix.ResNsearch(state, dname, class, typ, ans, anslen)
+ return x
+}
+
+func _C_res_nclose(state *_C_struct___res_state) {
+ unix.ResNclose(state)
+}
+
+func cgoNameinfoPTR(b []byte, sa *syscall.RawSockaddr, salen int) (int, error) {
+ return unix.Getnameinfo(sa, salen, &b[0], len(b), nil, 0, unix.NI_NAMEREQD)
+}
+
+func cgoSockaddrInet4(ip IP) *syscall.RawSockaddr {
+ sa := syscall.RawSockaddrInet4{Len: syscall.SizeofSockaddrInet4, Family: syscall.AF_INET}
+ copy(sa.Addr[:], ip)
+ return (*syscall.RawSockaddr)(unsafe.Pointer(&sa))
+}
+
+func cgoSockaddrInet6(ip IP, zone int) *syscall.RawSockaddr {
+ sa := syscall.RawSockaddrInet6{Len: syscall.SizeofSockaddrInet6, Family: syscall.AF_INET6, Scope_id: uint32(zone)}
+ copy(sa.Addr[:], ip)
+ return (*syscall.RawSockaddr)(unsafe.Pointer(&sa))
+}
diff --git a/go/src/net/cgo_unix_test.go b/go/src/net/cgo_unix_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..9aaeccc5f057090a3ee2bdc184c801b5f7b1cff2
--- /dev/null
+++ b/go/src/net/cgo_unix_test.go
@@ -0,0 +1,79 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !netgo && ((cgo && unix) || darwin)
+
+package net
+
+import (
+ "context"
+ "internal/testenv"
+ "testing"
+)
+
+func TestCgoLookupIP(t *testing.T) {
+ defer dnsWaitGroup.Wait()
+ ctx := context.Background()
+ _, err := cgoLookupIP(ctx, "ip", "localhost")
+ if err != nil {
+ t.Error(err)
+ }
+}
+
+func TestCgoLookupIPWithCancel(t *testing.T) {
+ defer dnsWaitGroup.Wait()
+ ctx, cancel := context.WithCancel(context.Background())
+ defer cancel()
+ _, err := cgoLookupIP(ctx, "ip", "localhost")
+ if err != nil {
+ t.Error(err)
+ }
+}
+
+func TestCgoLookupPort(t *testing.T) {
+ defer dnsWaitGroup.Wait()
+ ctx := context.Background()
+ _, err := cgoLookupPort(ctx, "tcp", "smtp")
+ if err != nil {
+ t.Error(err)
+ }
+}
+
+func TestCgoLookupPortWithCancel(t *testing.T) {
+ defer dnsWaitGroup.Wait()
+ ctx, cancel := context.WithCancel(context.Background())
+ defer cancel()
+ _, err := cgoLookupPort(ctx, "tcp", "smtp")
+ if err != nil {
+ t.Error(err)
+ }
+}
+
+func TestCgoLookupPTR(t *testing.T) {
+ defer dnsWaitGroup.Wait()
+ ctx := context.Background()
+ _, err := cgoLookupPTR(ctx, "127.0.0.1")
+ if err != nil {
+ t.Error(err)
+ }
+}
+
+func TestCgoLookupPTRWithCancel(t *testing.T) {
+ defer dnsWaitGroup.Wait()
+ ctx, cancel := context.WithCancel(context.Background())
+ defer cancel()
+ _, err := cgoLookupPTR(ctx, "127.0.0.1")
+ if err != nil {
+ t.Error(err)
+ }
+}
+
+func TestCgoLookupCNAME(t *testing.T) {
+ mustHaveExternalNetwork(t)
+ testenv.SkipFlakyNet(t)
+ defer dnsWaitGroup.Wait()
+ if _, err := cgoLookupCNAME(t.Context(), "www.iana.org."); err != nil {
+ t.Error(err)
+ }
+}
diff --git a/go/src/net/conf.go b/go/src/net/conf.go
new file mode 100644
index 0000000000000000000000000000000000000000..92c5618d1ec2217ff50bdffe38a63d5b19773ed6
--- /dev/null
+++ b/go/src/net/conf.go
@@ -0,0 +1,535 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "errors"
+ "internal/bytealg"
+ "internal/godebug"
+ "internal/stringslite"
+ "io/fs"
+ "os"
+ "runtime"
+ "sync"
+)
+
+// The net package's name resolution is rather complicated.
+// There are two main approaches, go and cgo.
+// The cgo resolver uses C functions like getaddrinfo.
+// The go resolver reads system files directly and
+// sends DNS packets directly to servers.
+//
+// The netgo build tag prefers the go resolver.
+// The netcgo build tag prefers the cgo resolver.
+//
+// The netgo build tag also prohibits the use of the cgo tool.
+// However, on Darwin, Plan 9, and Windows the cgo resolver is still available.
+// On those systems the cgo resolver does not require the cgo tool.
+// (The term "cgo resolver" was locked in by GODEBUG settings
+// at a time when the cgo resolver did require the cgo tool.)
+//
+// Adding netdns=go to GODEBUG will prefer the go resolver.
+// Adding netdns=cgo to GODEBUG will prefer the cgo resolver.
+//
+// The Resolver struct has a PreferGo field that user code
+// may set to prefer the go resolver. It is documented as being
+// equivalent to adding netdns=go to GODEBUG.
+//
+// When deciding which resolver to use, we first check the PreferGo field.
+// If that is not set, we check the GODEBUG setting.
+// If that is not set, we check the netgo or netcgo build tag.
+// If none of those are set, we normally prefer the go resolver by default.
+// However, if the cgo resolver is available,
+// there is a complex set of conditions for which we prefer the cgo resolver.
+//
+// Other files define the netGoBuildTag, netCgoBuildTag, and cgoAvailable
+// constants.
+
+// conf is used to determine name resolution configuration.
+type conf struct {
+ netGo bool // prefer go approach, based on build tag and GODEBUG
+ netCgo bool // prefer cgo approach, based on build tag and GODEBUG
+
+ dnsDebugLevel int // from GODEBUG
+
+ preferCgo bool // if no explicit preference, use cgo
+
+ goos string // copy of runtime.GOOS, used for testing
+ mdnsTest mdnsTest // assume /etc/mdns.allow exists, for testing
+}
+
+// mdnsTest is for testing only.
+type mdnsTest int
+
+const (
+ mdnsFromSystem mdnsTest = iota
+ mdnsAssumeExists
+ mdnsAssumeDoesNotExist
+)
+
+var (
+ confOnce sync.Once // guards init of confVal via initConfVal
+ confVal = &conf{goos: runtime.GOOS}
+)
+
+// systemConf returns the machine's network configuration.
+func systemConf() *conf {
+ confOnce.Do(initConfVal)
+ return confVal
+}
+
+// initConfVal initializes confVal based on the environment
+// that will not change during program execution.
+func initConfVal() {
+ dnsMode, debugLevel := goDebugNetDNS()
+ confVal.netGo = netGoBuildTag || dnsMode == "go"
+ confVal.netCgo = netCgoBuildTag || dnsMode == "cgo"
+ confVal.dnsDebugLevel = debugLevel
+
+ if confVal.dnsDebugLevel > 0 {
+ defer func() {
+ if confVal.dnsDebugLevel > 1 {
+ println("go package net: confVal.netCgo =", confVal.netCgo, " netGo =", confVal.netGo)
+ }
+ if dnsMode != "go" && dnsMode != "cgo" && dnsMode != "" {
+ println("go package net: GODEBUG=netdns contains an invalid dns mode, ignoring it")
+ }
+ switch {
+ case netGoBuildTag || !cgoAvailable:
+ if dnsMode == "cgo" {
+ println("go package net: ignoring GODEBUG=netdns=cgo as the binary was compiled without support for the cgo resolver")
+ } else {
+ println("go package net: using the Go DNS resolver")
+ }
+ case netCgoBuildTag:
+ if dnsMode == "go" {
+ println("go package net: GODEBUG setting forcing use of the Go resolver")
+ } else {
+ println("go package net: using the cgo DNS resolver")
+ }
+ default:
+ if dnsMode == "go" {
+ println("go package net: GODEBUG setting forcing use of the Go resolver")
+ } else if dnsMode == "cgo" {
+ println("go package net: GODEBUG setting forcing use of the cgo resolver")
+ } else {
+ println("go package net: dynamic selection of DNS resolver")
+ }
+ }
+ }()
+ }
+
+ // The remainder of this function sets preferCgo based on
+ // conditions that will not change during program execution.
+
+ // By default, prefer the go resolver.
+ confVal.preferCgo = false
+
+ // If the cgo resolver is not available, we can't prefer it.
+ if !cgoAvailable {
+ return
+ }
+
+ // Some operating systems always prefer the cgo resolver.
+ if goosPrefersCgo() {
+ confVal.preferCgo = true
+ return
+ }
+
+ // The remaining checks are specific to Unix systems.
+ switch runtime.GOOS {
+ case "plan9", "windows", "js", "wasip1":
+ return
+ }
+
+ // If any environment-specified resolver options are specified,
+ // prefer the cgo resolver.
+ // Note that LOCALDOMAIN can change behavior merely by being
+ // specified with the empty string.
+ _, localDomainDefined := os.LookupEnv("LOCALDOMAIN")
+ if localDomainDefined || os.Getenv("RES_OPTIONS") != "" || os.Getenv("HOSTALIASES") != "" {
+ confVal.preferCgo = true
+ return
+ }
+
+ // OpenBSD apparently lets you override the location of resolv.conf
+ // with ASR_CONFIG. If we notice that, defer to libc.
+ if runtime.GOOS == "openbsd" && os.Getenv("ASR_CONFIG") != "" {
+ confVal.preferCgo = true
+ return
+ }
+}
+
+// goosPrefersCgo reports whether the GOOS value passed in prefers
+// the cgo resolver.
+func goosPrefersCgo() bool {
+ switch runtime.GOOS {
+ // Historically on Windows and Plan 9 we prefer the
+ // cgo resolver (which doesn't use the cgo tool) rather than
+ // the go resolver. This is because originally these
+ // systems did not support the go resolver.
+ // Keep it this way for better compatibility.
+ // Perhaps we can revisit this some day.
+ case "windows", "plan9":
+ return true
+
+ // Darwin pops up annoying dialog boxes if programs try to
+ // do their own DNS requests, so prefer cgo.
+ case "darwin", "ios":
+ return true
+
+ // DNS requests don't work on Android, so prefer the cgo resolver.
+ // Issue #10714.
+ case "android":
+ return true
+
+ default:
+ return false
+ }
+}
+
+// mustUseGoResolver reports whether a DNS lookup of any sort is
+// required to use the go resolver. The provided Resolver is optional.
+// This will report true if the cgo resolver is not available.
+func (c *conf) mustUseGoResolver(r *Resolver) bool {
+ if !cgoAvailable {
+ return true
+ }
+
+ if runtime.GOOS == "plan9" {
+ // TODO(bradfitz): for now we only permit use of the PreferGo
+ // implementation when there's a non-nil Resolver with a
+ // non-nil Dialer. This is a sign that the code is trying
+ // to use their DNS-speaking net.Conn (such as an in-memory
+ // DNS cache) and they don't want to actually hit the network.
+ // Once we add support for looking the default DNS servers
+ // from plan9, though, then we can relax this.
+ if r == nil || r.Dial == nil {
+ return false
+ }
+ }
+
+ return c.netGo || r.preferGo()
+}
+
+// addrLookupOrder determines which strategy to use to resolve addresses.
+// The provided Resolver is optional. nil means to not consider its options.
+// It also returns dnsConfig when it was used to determine the lookup order.
+func (c *conf) addrLookupOrder(r *Resolver, addr string) (ret hostLookupOrder, dnsConf *dnsConfig) {
+ if c.dnsDebugLevel > 1 {
+ defer func() {
+ print("go package net: addrLookupOrder(", addr, ") = ", ret.String(), "\n")
+ }()
+ }
+ return c.lookupOrder(r, "")
+}
+
+// hostLookupOrder determines which strategy to use to resolve hostname.
+// The provided Resolver is optional. nil means to not consider its options.
+// It also returns dnsConfig when it was used to determine the lookup order.
+func (c *conf) hostLookupOrder(r *Resolver, hostname string) (ret hostLookupOrder, dnsConf *dnsConfig) {
+ if c.dnsDebugLevel > 1 {
+ defer func() {
+ print("go package net: hostLookupOrder(", hostname, ") = ", ret.String(), "\n")
+ }()
+ }
+ return c.lookupOrder(r, hostname)
+}
+
+func (c *conf) lookupOrder(r *Resolver, hostname string) (ret hostLookupOrder, dnsConf *dnsConfig) {
+ // fallbackOrder is the order we return if we can't figure it out.
+ var fallbackOrder hostLookupOrder
+
+ var canUseCgo bool
+ if c.mustUseGoResolver(r) {
+ // Go resolver was explicitly requested
+ // or cgo resolver is not available.
+ // Figure out the order below.
+ fallbackOrder = hostLookupFilesDNS
+ canUseCgo = false
+ } else if c.netCgo {
+ // Cgo resolver was explicitly requested.
+ return hostLookupCgo, nil
+ } else if c.preferCgo {
+ // Given a choice, we prefer the cgo resolver.
+ return hostLookupCgo, nil
+ } else {
+ // Neither resolver was explicitly requested
+ // and we have no preference.
+
+ if bytealg.IndexByteString(hostname, '\\') != -1 || bytealg.IndexByteString(hostname, '%') != -1 {
+ // Don't deal with special form hostnames
+ // with backslashes or '%'.
+ return hostLookupCgo, nil
+ }
+
+ // If something is unrecognized, use cgo.
+ fallbackOrder = hostLookupCgo
+ canUseCgo = true
+ }
+
+ // On systems that don't use /etc/resolv.conf or /etc/nsswitch.conf, we are done.
+ switch c.goos {
+ case "windows", "plan9", "android", "ios":
+ return fallbackOrder, nil
+ }
+
+ // Try to figure out the order to use for searches.
+ // If we don't recognize something, use fallbackOrder.
+ // That will use cgo unless the Go resolver was explicitly requested.
+ // If we do figure out the order, return something other
+ // than fallbackOrder to use the Go resolver with that order.
+
+ dnsConf = getSystemDNSConfig()
+
+ if canUseCgo && dnsConf.err != nil && !errors.Is(dnsConf.err, fs.ErrNotExist) && !errors.Is(dnsConf.err, fs.ErrPermission) {
+ // We can't read the resolv.conf file, so use cgo if we can.
+ return hostLookupCgo, dnsConf
+ }
+
+ if canUseCgo && dnsConf.unknownOpt {
+ // We didn't recognize something in resolv.conf,
+ // so use cgo if we can.
+ return hostLookupCgo, dnsConf
+ }
+
+ // OpenBSD is unique and doesn't use nsswitch.conf.
+ // It also doesn't support mDNS.
+ if c.goos == "openbsd" {
+ // OpenBSD's resolv.conf manpage says that a
+ // non-existent resolv.conf means "lookup" defaults
+ // to only "files", without DNS lookups.
+ if errors.Is(dnsConf.err, fs.ErrNotExist) {
+ return hostLookupFiles, dnsConf
+ }
+
+ lookup := dnsConf.lookup
+ if len(lookup) == 0 {
+ // https://www.openbsd.org/cgi-bin/man.cgi/OpenBSD-current/man5/resolv.conf.5
+ // "If the lookup keyword is not used in the
+ // system's resolv.conf file then the assumed
+ // order is 'bind file'"
+ return hostLookupDNSFiles, dnsConf
+ }
+ if len(lookup) < 1 || len(lookup) > 2 {
+ // We don't recognize this format.
+ return fallbackOrder, dnsConf
+ }
+ switch lookup[0] {
+ case "bind":
+ if len(lookup) == 2 {
+ if lookup[1] == "file" {
+ return hostLookupDNSFiles, dnsConf
+ }
+ // Unrecognized.
+ return fallbackOrder, dnsConf
+ }
+ return hostLookupDNS, dnsConf
+ case "file":
+ if len(lookup) == 2 {
+ if lookup[1] == "bind" {
+ return hostLookupFilesDNS, dnsConf
+ }
+ // Unrecognized.
+ return fallbackOrder, dnsConf
+ }
+ return hostLookupFiles, dnsConf
+ default:
+ // Unrecognized.
+ return fallbackOrder, dnsConf
+ }
+
+ // We always return before this point.
+ // The code below is for non-OpenBSD.
+ }
+
+ // Canonicalize the hostname by removing any trailing dot.
+ hostname = stringslite.TrimSuffix(hostname, ".")
+
+ nss := getSystemNSS()
+ srcs := nss.sources["hosts"]
+ // If /etc/nsswitch.conf doesn't exist or doesn't specify any
+ // sources for "hosts", assume Go's DNS will work fine.
+ if errors.Is(nss.err, fs.ErrNotExist) || (nss.err == nil && len(srcs) == 0) {
+ if canUseCgo && c.goos == "solaris" {
+ // illumos defaults to
+ // "nis [NOTFOUND=return] files",
+ // which the go resolver doesn't support.
+ return hostLookupCgo, dnsConf
+ }
+
+ return hostLookupFilesDNS, dnsConf
+ }
+ if nss.err != nil {
+ // We failed to parse or open nsswitch.conf, so
+ // we have nothing to base an order on.
+ return fallbackOrder, dnsConf
+ }
+
+ var hasDNSSource bool
+ var hasDNSSourceChecked bool
+
+ var filesSource, dnsSource bool
+ var first string
+ for i, src := range srcs {
+ if src.source == "files" || src.source == "dns" {
+ if canUseCgo && !src.standardCriteria() {
+ // non-standard; let libc deal with it.
+ return hostLookupCgo, dnsConf
+ }
+ if src.source == "files" {
+ filesSource = true
+ } else {
+ hasDNSSource = true
+ hasDNSSourceChecked = true
+ dnsSource = true
+ }
+ if first == "" {
+ first = src.source
+ }
+ continue
+ }
+
+ if canUseCgo {
+ switch {
+ case hostname != "" && src.source == "myhostname":
+ // Let the cgo resolver handle myhostname
+ // if we are looking up the local hostname.
+ if isLocalhost(hostname) || isGateway(hostname) || isOutbound(hostname) {
+ return hostLookupCgo, dnsConf
+ }
+ hn, err := getHostname()
+ if err != nil || stringsEqualFold(hostname, hn) {
+ return hostLookupCgo, dnsConf
+ }
+ continue
+ case hostname != "" && stringslite.HasPrefix(src.source, "mdns"):
+ if stringsHasSuffixFold(hostname, ".local") {
+ // Per RFC 6762, the ".local" TLD is special. And
+ // because Go's native resolver doesn't do mDNS or
+ // similar local resolution mechanisms, assume that
+ // libc might (via Avahi, etc) and use cgo.
+ return hostLookupCgo, dnsConf
+ }
+
+ // We don't parse mdns.allow files. They're rare. If one
+ // exists, it might list other TLDs (besides .local) or even
+ // '*', so just let libc deal with it.
+ var haveMDNSAllow bool
+ switch c.mdnsTest {
+ case mdnsFromSystem:
+ _, err := os.Stat("/etc/mdns.allow")
+ if err != nil && !errors.Is(err, fs.ErrNotExist) {
+ // Let libc figure out what is going on.
+ return hostLookupCgo, dnsConf
+ }
+ haveMDNSAllow = err == nil
+ case mdnsAssumeExists:
+ haveMDNSAllow = true
+ case mdnsAssumeDoesNotExist:
+ haveMDNSAllow = false
+ }
+ if haveMDNSAllow {
+ return hostLookupCgo, dnsConf
+ }
+ continue
+ default:
+ // Some source we don't know how to deal with.
+ return hostLookupCgo, dnsConf
+ }
+ }
+
+ if !hasDNSSourceChecked {
+ hasDNSSourceChecked = true
+ for _, v := range srcs[i+1:] {
+ if v.source == "dns" {
+ hasDNSSource = true
+ break
+ }
+ }
+ }
+
+ // If we saw a source we don't recognize, which can only
+ // happen if we can't use the cgo resolver, treat it as DNS,
+ // but only when there is no dns in all other sources.
+ if !hasDNSSource {
+ dnsSource = true
+ if first == "" {
+ first = "dns"
+ }
+ }
+ }
+
+ // Cases where Go can handle it without cgo and C thread overhead,
+ // or where the Go resolver has been forced.
+ switch {
+ case filesSource && dnsSource:
+ if first == "files" {
+ return hostLookupFilesDNS, dnsConf
+ } else {
+ return hostLookupDNSFiles, dnsConf
+ }
+ case filesSource:
+ return hostLookupFiles, dnsConf
+ case dnsSource:
+ return hostLookupDNS, dnsConf
+ }
+
+ // Something weird. Fallback to the default.
+ return fallbackOrder, dnsConf
+}
+
+var netdns = godebug.New("netdns")
+
+// goDebugNetDNS parses the value of the GODEBUG "netdns" value.
+// The netdns value can be of the form:
+//
+// 1 // debug level 1
+// 2 // debug level 2
+// cgo // use cgo for DNS lookups
+// go // use go for DNS lookups
+// cgo+1 // use cgo for DNS lookups + debug level 1
+// 1+cgo // same
+// cgo+2 // same, but debug level 2
+//
+// etc.
+func goDebugNetDNS() (dnsMode string, debugLevel int) {
+ goDebug := netdns.Value()
+ parsePart := func(s string) {
+ if s == "" {
+ return
+ }
+ if '0' <= s[0] && s[0] <= '9' {
+ debugLevel, _, _ = dtoi(s)
+ } else {
+ dnsMode = s
+ }
+ }
+ if i := bytealg.IndexByteString(goDebug, '+'); i != -1 {
+ parsePart(goDebug[:i])
+ parsePart(goDebug[i+1:])
+ return
+ }
+ parsePart(goDebug)
+ return
+}
+
+// isLocalhost reports whether h should be considered a "localhost"
+// name for the myhostname NSS module.
+func isLocalhost(h string) bool {
+ return stringsEqualFold(h, "localhost") || stringsEqualFold(h, "localhost.localdomain") || stringsHasSuffixFold(h, ".localhost") || stringsHasSuffixFold(h, ".localhost.localdomain")
+}
+
+// isGateway reports whether h should be considered a "gateway"
+// name for the myhostname NSS module.
+func isGateway(h string) bool {
+ return stringsEqualFold(h, "_gateway")
+}
+
+// isOutbound reports whether h should be considered an "outbound"
+// name for the myhostname NSS module.
+func isOutbound(h string) bool {
+ return stringsEqualFold(h, "_outbound")
+}
diff --git a/go/src/net/conf_test.go b/go/src/net/conf_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..6ebd6be635c95ad7a4379eb2d4d5c82f9574d832
--- /dev/null
+++ b/go/src/net/conf_test.go
@@ -0,0 +1,461 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+package net
+
+import (
+ "io/fs"
+ "os"
+ "testing"
+ "time"
+)
+
+type nssHostTest struct {
+ host string
+ localhost string
+ want hostLookupOrder
+}
+
+func nssStr(t *testing.T, s string) *nssConf {
+ f, err := os.CreateTemp(t.TempDir(), "nss")
+ if err != nil {
+ t.Fatal(err)
+ }
+ if _, err := f.WriteString(s); err != nil {
+ t.Fatal(err)
+ }
+ if err := f.Close(); err != nil {
+ t.Fatal(err)
+ }
+ return parseNSSConfFile(f.Name())
+}
+
+// represents a dnsConfig returned by parsing a nonexistent resolv.conf
+var defaultResolvConf = &dnsConfig{
+ servers: defaultNS,
+ ndots: 1,
+ timeout: 5,
+ attempts: 2,
+ err: fs.ErrNotExist,
+}
+
+func TestConfHostLookupOrder(t *testing.T) {
+ // These tests are written for a system with cgo available,
+ // without using the netgo tag.
+ if netGoBuildTag {
+ t.Skip("skipping test because net package built with netgo tag")
+ }
+ if !cgoAvailable {
+ t.Skip("skipping test because cgo resolver not available")
+ }
+
+ tests := []struct {
+ name string
+ c *conf
+ nss *nssConf
+ resolver *Resolver
+ resolv *dnsConfig
+ hostTests []nssHostTest
+ }{
+ {
+ name: "force",
+ c: &conf{
+ preferCgo: true,
+ netCgo: true,
+ },
+ resolv: defaultResolvConf,
+ nss: nssStr(t, "foo: bar"),
+ hostTests: []nssHostTest{
+ {"foo.local", "myhostname", hostLookupCgo},
+ {"google.com", "myhostname", hostLookupCgo},
+ },
+ },
+ {
+ name: "netgo_dns_before_files",
+ c: &conf{
+ netGo: true,
+ },
+ resolv: defaultResolvConf,
+ nss: nssStr(t, "hosts: dns files"),
+ hostTests: []nssHostTest{
+ {"x.com", "myhostname", hostLookupDNSFiles},
+ },
+ },
+ {
+ name: "netgo_fallback_on_cgo",
+ c: &conf{
+ netGo: true,
+ },
+ resolv: defaultResolvConf,
+ nss: nssStr(t, "hosts: dns files something_custom"),
+ hostTests: []nssHostTest{
+ {"x.com", "myhostname", hostLookupDNSFiles},
+ },
+ },
+ {
+ name: "ubuntu_trusty_avahi",
+ c: &conf{
+ mdnsTest: mdnsAssumeDoesNotExist,
+ },
+ resolv: defaultResolvConf,
+ nss: nssStr(t, "hosts: files mdns4_minimal [NOTFOUND=return] dns mdns4"),
+ hostTests: []nssHostTest{
+ {"foo.local", "myhostname", hostLookupCgo},
+ {"foo.local.", "myhostname", hostLookupCgo},
+ {"foo.LOCAL", "myhostname", hostLookupCgo},
+ {"foo.LOCAL.", "myhostname", hostLookupCgo},
+ {"google.com", "myhostname", hostLookupFilesDNS},
+ },
+ },
+ {
+ name: "freebsdlinux_no_resolv_conf",
+ c: &conf{
+ goos: "freebsd",
+ },
+ resolv: defaultResolvConf,
+ nss: nssStr(t, "foo: bar"),
+ hostTests: []nssHostTest{{"google.com", "myhostname", hostLookupFilesDNS}},
+ },
+ // On OpenBSD, no resolv.conf means no DNS.
+ {
+ name: "openbsd_no_resolv_conf",
+ c: &conf{
+ goos: "openbsd",
+ },
+ resolv: defaultResolvConf,
+ hostTests: []nssHostTest{{"google.com", "myhostname", hostLookupFiles}},
+ },
+ {
+ name: "solaris_no_nsswitch",
+ c: &conf{
+ goos: "solaris",
+ },
+ resolv: defaultResolvConf,
+ nss: &nssConf{err: fs.ErrNotExist},
+ hostTests: []nssHostTest{{"google.com", "myhostname", hostLookupCgo}},
+ },
+ {
+ name: "openbsd_lookup_bind_file",
+ c: &conf{
+ goos: "openbsd",
+ },
+ resolv: &dnsConfig{lookup: []string{"bind", "file"}},
+ hostTests: []nssHostTest{
+ {"google.com", "myhostname", hostLookupDNSFiles},
+ {"foo.local", "myhostname", hostLookupDNSFiles},
+ },
+ },
+ {
+ name: "openbsd_lookup_file_bind",
+ c: &conf{
+ goos: "openbsd",
+ },
+ resolv: &dnsConfig{lookup: []string{"file", "bind"}},
+ hostTests: []nssHostTest{{"google.com", "myhostname", hostLookupFilesDNS}},
+ },
+ {
+ name: "openbsd_lookup_bind",
+ c: &conf{
+ goos: "openbsd",
+ },
+ resolv: &dnsConfig{lookup: []string{"bind"}},
+ hostTests: []nssHostTest{{"google.com", "myhostname", hostLookupDNS}},
+ },
+ {
+ name: "openbsd_lookup_file",
+ c: &conf{
+ goos: "openbsd",
+ },
+ resolv: &dnsConfig{lookup: []string{"file"}},
+ hostTests: []nssHostTest{{"google.com", "myhostname", hostLookupFiles}},
+ },
+ {
+ name: "openbsd_lookup_yp",
+ c: &conf{
+ goos: "openbsd",
+ },
+ resolv: &dnsConfig{lookup: []string{"file", "bind", "yp"}},
+ hostTests: []nssHostTest{{"google.com", "myhostname", hostLookupCgo}},
+ },
+ {
+ name: "openbsd_lookup_two",
+ c: &conf{
+ goos: "openbsd",
+ },
+ resolv: &dnsConfig{lookup: []string{"file", "foo"}},
+ hostTests: []nssHostTest{{"google.com", "myhostname", hostLookupCgo}},
+ },
+ {
+ name: "openbsd_lookup_empty",
+ c: &conf{
+ goos: "openbsd",
+ },
+ resolv: &dnsConfig{lookup: nil},
+ hostTests: []nssHostTest{{"google.com", "myhostname", hostLookupDNSFiles}},
+ },
+ {
+ name: "linux_no_nsswitch.conf",
+ c: &conf{
+ goos: "linux",
+ },
+ resolv: defaultResolvConf,
+ nss: &nssConf{err: fs.ErrNotExist},
+ hostTests: []nssHostTest{{"google.com", "myhostname", hostLookupFilesDNS}},
+ },
+ {
+ name: "linux_empty_nsswitch.conf",
+ c: &conf{
+ goos: "linux",
+ },
+ resolv: defaultResolvConf,
+ nss: nssStr(t, ""),
+ hostTests: []nssHostTest{{"google.com", "myhostname", hostLookupFilesDNS}},
+ },
+ {
+ name: "files_mdns_dns",
+ c: &conf{
+ mdnsTest: mdnsAssumeDoesNotExist,
+ },
+ resolv: defaultResolvConf,
+ nss: nssStr(t, "hosts: files mdns dns"),
+ hostTests: []nssHostTest{
+ {"x.com", "myhostname", hostLookupFilesDNS},
+ {"x.local", "myhostname", hostLookupCgo},
+ },
+ },
+ {
+ name: "dns_special_hostnames",
+ c: &conf{},
+ resolv: defaultResolvConf,
+ nss: nssStr(t, "hosts: dns"),
+ hostTests: []nssHostTest{
+ {"x.com", "myhostname", hostLookupDNS},
+ {"x\\.com", "myhostname", hostLookupCgo}, // punt on weird glibc escape
+ {"foo.com%en0", "myhostname", hostLookupCgo}, // and IPv6 zones
+ },
+ },
+ {
+ name: "mdns_allow",
+ c: &conf{
+ mdnsTest: mdnsAssumeExists,
+ },
+ resolv: defaultResolvConf,
+ nss: nssStr(t, "hosts: files mdns dns"),
+ hostTests: []nssHostTest{
+ {"x.com", "myhostname", hostLookupCgo},
+ {"x.local", "myhostname", hostLookupCgo},
+ },
+ },
+ {
+ name: "files_dns",
+ c: &conf{},
+ resolv: defaultResolvConf,
+ nss: nssStr(t, "hosts: files dns"),
+ hostTests: []nssHostTest{
+ {"x.com", "myhostname", hostLookupFilesDNS},
+ {"x", "myhostname", hostLookupFilesDNS},
+ {"x.local", "myhostname", hostLookupFilesDNS},
+ },
+ },
+ {
+ name: "dns_files",
+ c: &conf{},
+ resolv: defaultResolvConf,
+ nss: nssStr(t, "hosts: dns files"),
+ hostTests: []nssHostTest{
+ {"x.com", "myhostname", hostLookupDNSFiles},
+ {"x", "myhostname", hostLookupDNSFiles},
+ {"x.local", "myhostname", hostLookupDNSFiles},
+ },
+ },
+ {
+ name: "something_custom",
+ c: &conf{},
+ resolv: defaultResolvConf,
+ nss: nssStr(t, "hosts: dns files something_custom"),
+ hostTests: []nssHostTest{
+ {"x.com", "myhostname", hostLookupCgo},
+ },
+ },
+ {
+ name: "myhostname",
+ c: &conf{},
+ resolv: defaultResolvConf,
+ nss: nssStr(t, "hosts: files dns myhostname"),
+ hostTests: []nssHostTest{
+ {"x.com", "myhostname", hostLookupFilesDNS},
+ {"myhostname", "myhostname", hostLookupCgo},
+ {"myHostname", "myhostname", hostLookupCgo},
+ {"myhostname.dot", "myhostname.dot", hostLookupCgo},
+ {"myHostname.dot", "myhostname.dot", hostLookupCgo},
+ {"_gateway", "myhostname", hostLookupCgo},
+ {"_Gateway", "myhostname", hostLookupCgo},
+ {"_outbound", "myhostname", hostLookupCgo},
+ {"_Outbound", "myhostname", hostLookupCgo},
+ {"localhost", "myhostname", hostLookupCgo},
+ {"Localhost", "myhostname", hostLookupCgo},
+ {"anything.localhost", "myhostname", hostLookupCgo},
+ {"Anything.localhost", "myhostname", hostLookupCgo},
+ {"localhost.localdomain", "myhostname", hostLookupCgo},
+ {"Localhost.Localdomain", "myhostname", hostLookupCgo},
+ {"anything.localhost.localdomain", "myhostname", hostLookupCgo},
+ {"Anything.Localhost.Localdomain", "myhostname", hostLookupCgo},
+ {"somehostname", "myhostname", hostLookupFilesDNS},
+ },
+ },
+ {
+ name: "ubuntu14.04.02",
+ c: &conf{
+ mdnsTest: mdnsAssumeDoesNotExist,
+ },
+ resolv: defaultResolvConf,
+ nss: nssStr(t, "hosts: files myhostname mdns4_minimal [NOTFOUND=return] dns mdns4"),
+ hostTests: []nssHostTest{
+ {"x.com", "myhostname", hostLookupFilesDNS},
+ {"somehostname", "myhostname", hostLookupFilesDNS},
+ {"myhostname", "myhostname", hostLookupCgo},
+ },
+ },
+ // Debian Squeeze is just "dns,files", but lists all
+ // the default criteria for dns, but then has a
+ // non-standard but redundant notfound=return for the
+ // files.
+ {
+ name: "debian_squeeze",
+ c: &conf{},
+ resolv: defaultResolvConf,
+ nss: nssStr(t, "hosts: dns [success=return notfound=continue unavail=continue tryagain=continue] files [notfound=return]"),
+ hostTests: []nssHostTest{
+ {"x.com", "myhostname", hostLookupDNSFiles},
+ {"somehostname", "myhostname", hostLookupDNSFiles},
+ },
+ },
+ {
+ name: "resolv.conf-unknown",
+ c: &conf{},
+ resolv: &dnsConfig{servers: defaultNS, ndots: 1, timeout: 5, attempts: 2, unknownOpt: true},
+ nss: nssStr(t, "foo: bar"),
+ hostTests: []nssHostTest{{"google.com", "myhostname", hostLookupCgo}},
+ },
+ // Issue 24393: make sure "Resolver.PreferGo = true" acts like netgo.
+ {
+ name: "resolver-prefergo",
+ resolver: &Resolver{PreferGo: true},
+ c: &conf{
+ preferCgo: true,
+ netCgo: true,
+ },
+ resolv: defaultResolvConf,
+ nss: nssStr(t, ""),
+ hostTests: []nssHostTest{
+ {"localhost", "myhostname", hostLookupFilesDNS},
+ },
+ },
+ {
+ name: "unknown-source",
+ resolver: &Resolver{PreferGo: true},
+ c: &conf{},
+ resolv: defaultResolvConf,
+ nss: nssStr(t, "hosts: resolve files"),
+ hostTests: []nssHostTest{
+ {"x.com", "myhostname", hostLookupDNSFiles},
+ },
+ },
+ {
+ name: "dns-among-unknown-sources",
+ resolver: &Resolver{PreferGo: true},
+ c: &conf{},
+ resolv: defaultResolvConf,
+ nss: nssStr(t, "hosts: mymachines files dns"),
+ hostTests: []nssHostTest{
+ {"x.com", "myhostname", hostLookupFilesDNS},
+ },
+ },
+ {
+ name: "dns-among-unknown-sources-2",
+ resolver: &Resolver{PreferGo: true},
+ c: &conf{},
+ resolv: defaultResolvConf,
+ nss: nssStr(t, "hosts: dns mymachines files"),
+ hostTests: []nssHostTest{
+ {"x.com", "myhostname", hostLookupDNSFiles},
+ },
+ },
+ }
+
+ origGetHostname := getHostname
+ defer func() { getHostname = origGetHostname }()
+ defer setSystemNSS(getSystemNSS(), 0)
+ conf, err := newResolvConfTest()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer conf.teardown()
+
+ for _, tt := range tests {
+ if !conf.forceUpdateConf(tt.resolv, time.Now().Add(time.Hour)) {
+ t.Errorf("%s: failed to change resolv config", tt.name)
+ }
+ for _, ht := range tt.hostTests {
+ getHostname = func() (string, error) { return ht.localhost, nil }
+ setSystemNSS(tt.nss, time.Hour)
+
+ gotOrder, _ := tt.c.hostLookupOrder(tt.resolver, ht.host)
+ if gotOrder != ht.want {
+ t.Errorf("%s: hostLookupOrder(%q) = %v; want %v", tt.name, ht.host, gotOrder, ht.want)
+ }
+ }
+ }
+}
+
+func TestAddrLookupOrder(t *testing.T) {
+ // This test is written for a system with cgo available,
+ // without using the netgo tag.
+ if netGoBuildTag {
+ t.Skip("skipping test because net package built with netgo tag")
+ }
+ if !cgoAvailable {
+ t.Skip("skipping test because cgo resolver not available")
+ }
+
+ defer setSystemNSS(getSystemNSS(), 0)
+ c, err := newResolvConfTest()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer c.teardown()
+
+ if !c.forceUpdateConf(defaultResolvConf, time.Now().Add(time.Hour)) {
+ t.Fatal("failed to change resolv config")
+ }
+
+ setSystemNSS(nssStr(t, "hosts: files myhostname dns"), time.Hour)
+ cnf := &conf{}
+ order, _ := cnf.addrLookupOrder(nil, "192.0.2.1")
+ if order != hostLookupCgo {
+ t.Errorf("addrLookupOrder returned: %v, want cgo", order)
+ }
+
+ setSystemNSS(nssStr(t, "hosts: files mdns4 dns"), time.Hour)
+ order, _ = cnf.addrLookupOrder(nil, "192.0.2.1")
+ if order != hostLookupCgo {
+ t.Errorf("addrLookupOrder returned: %v, want cgo", order)
+ }
+
+}
+
+func setSystemNSS(nss *nssConf, addDur time.Duration) {
+ nssConfig.mu.Lock()
+ nssConfig.nssConf = nss
+ nssConfig.mu.Unlock()
+ nssConfig.acquireSema()
+ nssConfig.lastChecked = time.Now().Add(addDur)
+ nssConfig.releaseSema()
+}
+
+func TestSystemConf(t *testing.T) {
+ systemConf()
+}
diff --git a/go/src/net/conn_test.go b/go/src/net/conn_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..87097e10ee3281c46744fad7d713fc7335f4a7d2
--- /dev/null
+++ b/go/src/net/conn_test.go
@@ -0,0 +1,63 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements API tests across platforms and should never have a build
+// constraint.
+
+package net
+
+import (
+ "testing"
+ "time"
+)
+
+// someTimeout is used just to test that net.Conn implementations
+// don't explode when their SetFooDeadline methods are called.
+// It isn't actually used for testing timeouts.
+const someTimeout = 1 * time.Hour
+
+func TestConnAndListener(t *testing.T) {
+ for i, network := range []string{"tcp", "unix", "unixpacket"} {
+ t.Run(network, func(t *testing.T) {
+ if !testableNetwork(network) {
+ t.Skipf("skipping %s test", network)
+ }
+
+ ls := newLocalServer(t, network)
+ defer ls.teardown()
+ ch := make(chan error, 1)
+ handler := func(ls *localServer, ln Listener) { ls.transponder(ln, ch) }
+ if err := ls.buildup(handler); err != nil {
+ t.Fatal(err)
+ }
+ if ls.Listener.Addr().Network() != network {
+ t.Fatalf("got %s; want %s", ls.Listener.Addr().Network(), network)
+ }
+
+ c, err := Dial(ls.Listener.Addr().Network(), ls.Listener.Addr().String())
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer c.Close()
+ if c.LocalAddr().Network() != network || c.RemoteAddr().Network() != network {
+ t.Fatalf("got %s->%s; want %s->%s", c.LocalAddr().Network(), c.RemoteAddr().Network(), network, network)
+ }
+ c.SetDeadline(time.Now().Add(someTimeout))
+ c.SetReadDeadline(time.Now().Add(someTimeout))
+ c.SetWriteDeadline(time.Now().Add(someTimeout))
+
+ if _, err := c.Write([]byte("CONN AND LISTENER TEST")); err != nil {
+ t.Fatal(err)
+ }
+ rb := make([]byte, 128)
+ if _, err := c.Read(rb); err != nil {
+ t.Fatal(err)
+ }
+
+ for err := range ch {
+ t.Errorf("#%d: %v", i, err)
+ }
+ })
+ }
+}
diff --git a/go/src/net/dial.go b/go/src/net/dial.go
new file mode 100644
index 0000000000000000000000000000000000000000..a87c57603a813ce70e64584da345507d1144db7d
--- /dev/null
+++ b/go/src/net/dial.go
@@ -0,0 +1,999 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "context"
+ "internal/bytealg"
+ "internal/godebug"
+ "internal/nettrace"
+ "net/netip"
+ "syscall"
+ "time"
+)
+
+const (
+ // defaultTCPKeepAliveIdle is a default constant value for TCP_KEEPIDLE.
+ // See go.dev/issue/31510 for details.
+ defaultTCPKeepAliveIdle = 15 * time.Second
+
+ // defaultTCPKeepAliveInterval is a default constant value for TCP_KEEPINTVL.
+ // It is the same as defaultTCPKeepAliveIdle, see go.dev/issue/31510 for details.
+ defaultTCPKeepAliveInterval = 15 * time.Second
+
+ // defaultTCPKeepAliveCount is a default constant value for TCP_KEEPCNT.
+ defaultTCPKeepAliveCount = 9
+
+ // For the moment, MultiPath TCP is used by default with listeners, if
+ // available, but not with dialers.
+ // See go.dev/issue/56539
+ defaultMPTCPEnabledListen = true
+ defaultMPTCPEnabledDial = false
+)
+
+// The type of service offered
+//
+// 0 == MPTCP disabled
+// 1 == MPTCP enabled
+// 2 == MPTCP enabled on listeners only
+// 3 == MPTCP enabled on dialers only
+var multipathtcp = godebug.New("multipathtcp")
+
+// mptcpStatusDial is a tristate for Multipath TCP on clients,
+// see go.dev/issue/56539
+type mptcpStatusDial uint8
+
+const (
+ // The value 0 is the system default, linked to defaultMPTCPEnabledDial
+ mptcpUseDefaultDial mptcpStatusDial = iota
+ mptcpEnabledDial
+ mptcpDisabledDial
+)
+
+func (m *mptcpStatusDial) get() bool {
+ switch *m {
+ case mptcpEnabledDial:
+ return true
+ case mptcpDisabledDial:
+ return false
+ }
+
+ // If MPTCP is forced via GODEBUG=multipathtcp=1
+ if multipathtcp.Value() == "1" || multipathtcp.Value() == "3" {
+ multipathtcp.IncNonDefault()
+
+ return true
+ }
+
+ return defaultMPTCPEnabledDial
+}
+
+func (m *mptcpStatusDial) set(use bool) {
+ if use {
+ *m = mptcpEnabledDial
+ } else {
+ *m = mptcpDisabledDial
+ }
+}
+
+// mptcpStatusListen is a tristate for Multipath TCP on servers,
+// see go.dev/issue/56539
+type mptcpStatusListen uint8
+
+const (
+ // The value 0 is the system default, linked to defaultMPTCPEnabledListen
+ mptcpUseDefaultListen mptcpStatusListen = iota
+ mptcpEnabledListen
+ mptcpDisabledListen
+)
+
+func (m *mptcpStatusListen) get() bool {
+ switch *m {
+ case mptcpEnabledListen:
+ return true
+ case mptcpDisabledListen:
+ return false
+ }
+
+ // If MPTCP is disabled via GODEBUG=multipathtcp=0 or only
+ // enabled on dialers, but not on listeners.
+ if multipathtcp.Value() == "0" || multipathtcp.Value() == "3" {
+ multipathtcp.IncNonDefault()
+
+ return false
+ }
+
+ return defaultMPTCPEnabledListen
+}
+
+func (m *mptcpStatusListen) set(use bool) {
+ if use {
+ *m = mptcpEnabledListen
+ } else {
+ *m = mptcpDisabledListen
+ }
+}
+
+// A Dialer contains options for connecting to an address.
+//
+// The zero value for each field is equivalent to dialing
+// without that option. Dialing with the zero value of Dialer
+// is therefore equivalent to just calling the [Dial] function.
+//
+// It is safe to call Dialer's methods concurrently.
+type Dialer struct {
+ // Timeout is the maximum amount of time a dial will wait for
+ // a connect to complete. If Deadline is also set, it may fail
+ // earlier.
+ //
+ // The default is no timeout.
+ //
+ // When using TCP and dialing a host name with multiple IP
+ // addresses, the timeout may be divided between them.
+ //
+ // With or without a timeout, the operating system may impose
+ // its own earlier timeout. For instance, TCP timeouts are
+ // often around 3 minutes.
+ Timeout time.Duration
+
+ // Deadline is the absolute point in time after which dials
+ // will fail. If Timeout is set, it may fail earlier.
+ // Zero means no deadline, or dependent on the operating system
+ // as with the Timeout option.
+ Deadline time.Time
+
+ // LocalAddr is the local address to use when dialing an
+ // address. The address must be of a compatible type for the
+ // network being dialed.
+ // If nil, a local address is automatically chosen.
+ LocalAddr Addr
+
+ // DualStack previously enabled RFC 6555 Fast Fallback
+ // support, also known as "Happy Eyeballs", in which IPv4 is
+ // tried soon if IPv6 appears to be misconfigured and
+ // hanging.
+ //
+ // Deprecated: Fast Fallback is enabled by default. To
+ // disable, set FallbackDelay to a negative value.
+ DualStack bool
+
+ // FallbackDelay specifies the length of time to wait before
+ // spawning a RFC 6555 Fast Fallback connection. That is, this
+ // is the amount of time to wait for IPv6 to succeed before
+ // assuming that IPv6 is misconfigured and falling back to
+ // IPv4.
+ //
+ // If zero, a default delay of 300ms is used.
+ // A negative value disables Fast Fallback support.
+ FallbackDelay time.Duration
+
+ // KeepAlive specifies the interval between keep-alive
+ // probes for an active network connection.
+ //
+ // KeepAlive is ignored if KeepAliveConfig.Enable is true.
+ //
+ // If zero, keep-alive probes are sent with a default value
+ // (currently 15 seconds), if supported by the protocol and operating
+ // system. Network protocols or operating systems that do
+ // not support keep-alive ignore this field.
+ // If negative, keep-alive probes are disabled.
+ KeepAlive time.Duration
+
+ // KeepAliveConfig specifies the keep-alive probe configuration
+ // for an active network connection, when supported by the
+ // protocol and operating system.
+ //
+ // If KeepAliveConfig.Enable is true, keep-alive probes are enabled.
+ // If KeepAliveConfig.Enable is false and KeepAlive is negative,
+ // keep-alive probes are disabled.
+ KeepAliveConfig KeepAliveConfig
+
+ // Resolver optionally specifies an alternate resolver to use.
+ Resolver *Resolver
+
+ // Cancel is an optional channel whose closure indicates that
+ // the dial should be canceled. Not all types of dials support
+ // cancellation.
+ //
+ // Deprecated: Use DialContext instead.
+ Cancel <-chan struct{}
+
+ // If Control is not nil, it is called after creating the network
+ // connection but before actually dialing.
+ //
+ // Network and address parameters passed to Control function are not
+ // necessarily the ones passed to Dial. Calling Dial with TCP networks
+ // will cause the Control function to be called with "tcp4" or "tcp6",
+ // UDP networks become "udp4" or "udp6", IP networks become "ip4" or "ip6",
+ // and other known networks are passed as-is.
+ //
+ // Control is ignored if ControlContext is not nil.
+ Control func(network, address string, c syscall.RawConn) error
+
+ // If ControlContext is not nil, it is called after creating the network
+ // connection but before actually dialing.
+ //
+ // Network and address parameters passed to ControlContext function are not
+ // necessarily the ones passed to Dial. Calling Dial with TCP networks
+ // will cause the ControlContext function to be called with "tcp4" or "tcp6",
+ // UDP networks become "udp4" or "udp6", IP networks become "ip4" or "ip6",
+ // and other known networks are passed as-is.
+ //
+ // If ControlContext is not nil, Control is ignored.
+ ControlContext func(ctx context.Context, network, address string, c syscall.RawConn) error
+
+ // If mptcpStatus is set to a value allowing Multipath TCP (MPTCP) to be
+ // used, any call to Dial with "tcp(4|6)" as network will use MPTCP if
+ // supported by the operating system.
+ mptcpStatus mptcpStatusDial
+}
+
+func (d *Dialer) dualStack() bool { return d.FallbackDelay >= 0 }
+
+func minNonzeroTime(a, b time.Time) time.Time {
+ if a.IsZero() {
+ return b
+ }
+ if b.IsZero() || a.Before(b) {
+ return a
+ }
+ return b
+}
+
+// deadline returns the earliest of:
+// - now+Timeout
+// - d.Deadline
+// - the context's deadline
+//
+// Or zero, if none of Timeout, Deadline, or context's deadline is set.
+func (d *Dialer) deadline(ctx context.Context, now time.Time) (earliest time.Time) {
+ if d.Timeout != 0 { // including negative, for historical reasons
+ earliest = now.Add(d.Timeout)
+ }
+ if d, ok := ctx.Deadline(); ok {
+ earliest = minNonzeroTime(earliest, d)
+ }
+ return minNonzeroTime(earliest, d.Deadline)
+}
+
+func (d *Dialer) resolver() *Resolver {
+ if d.Resolver != nil {
+ return d.Resolver
+ }
+ return DefaultResolver
+}
+
+// partialDeadline returns the deadline to use for a single address,
+// when multiple addresses are pending.
+func partialDeadline(now, deadline time.Time, addrsRemaining int) (time.Time, error) {
+ if deadline.IsZero() {
+ return deadline, nil
+ }
+ timeRemaining := deadline.Sub(now)
+ if timeRemaining <= 0 {
+ return time.Time{}, errTimeout
+ }
+ // Tentatively allocate equal time to each remaining address.
+ timeout := timeRemaining / time.Duration(addrsRemaining)
+ // If the time per address is too short, steal from the end of the list.
+ const saneMinimum = 2 * time.Second
+ if timeout < saneMinimum {
+ if timeRemaining < saneMinimum {
+ timeout = timeRemaining
+ } else {
+ timeout = saneMinimum
+ }
+ }
+ return now.Add(timeout), nil
+}
+
+func (d *Dialer) fallbackDelay() time.Duration {
+ if d.FallbackDelay > 0 {
+ return d.FallbackDelay
+ } else {
+ return 300 * time.Millisecond
+ }
+}
+
+func parseNetwork(ctx context.Context, network string, needsProto bool) (afnet string, proto int, err error) {
+ i := bytealg.LastIndexByteString(network, ':')
+ if i < 0 { // no colon
+ switch network {
+ case "tcp", "tcp4", "tcp6":
+ case "udp", "udp4", "udp6":
+ case "ip", "ip4", "ip6":
+ if needsProto {
+ return "", 0, UnknownNetworkError(network)
+ }
+ case "unix", "unixgram", "unixpacket":
+ default:
+ return "", 0, UnknownNetworkError(network)
+ }
+ return network, 0, nil
+ }
+ afnet = network[:i]
+ switch afnet {
+ case "ip", "ip4", "ip6":
+ protostr := network[i+1:]
+ proto, i, ok := dtoi(protostr)
+ if !ok || i != len(protostr) {
+ proto, err = lookupProtocol(ctx, protostr)
+ if err != nil {
+ return "", 0, err
+ }
+ }
+ return afnet, proto, nil
+ }
+ return "", 0, UnknownNetworkError(network)
+}
+
+// resolveAddrList resolves addr using hint and returns a list of
+// addresses. The result contains at least one address when error is
+// nil.
+func (r *Resolver) resolveAddrList(ctx context.Context, op, network, addr string, hint Addr) (addrList, error) {
+ afnet, _, err := parseNetwork(ctx, network, true)
+ if err != nil {
+ return nil, err
+ }
+ if op == "dial" && addr == "" {
+ return nil, errMissingAddress
+ }
+ switch afnet {
+ case "unix", "unixgram", "unixpacket":
+ addr, err := ResolveUnixAddr(afnet, addr)
+ if err != nil {
+ return nil, err
+ }
+ if op == "dial" && hint != nil && addr.Network() != hint.Network() {
+ return nil, &AddrError{Err: "mismatched local address type", Addr: hint.String()}
+ }
+ return addrList{addr}, nil
+ }
+ addrs, err := r.internetAddrList(ctx, afnet, addr)
+ if err != nil || op != "dial" || hint == nil {
+ return addrs, err
+ }
+ var (
+ tcp *TCPAddr
+ udp *UDPAddr
+ ip *IPAddr
+ wildcard bool
+ )
+ switch hint := hint.(type) {
+ case *TCPAddr:
+ tcp = hint
+ wildcard = tcp.isWildcard()
+ case *UDPAddr:
+ udp = hint
+ wildcard = udp.isWildcard()
+ case *IPAddr:
+ ip = hint
+ wildcard = ip.isWildcard()
+ }
+ naddrs := addrs[:0]
+ for _, addr := range addrs {
+ if addr.Network() != hint.Network() {
+ return nil, &AddrError{Err: "mismatched local address type", Addr: hint.String()}
+ }
+ switch addr := addr.(type) {
+ case *TCPAddr:
+ if !wildcard && !addr.isWildcard() && !addr.IP.matchAddrFamily(tcp.IP) {
+ continue
+ }
+ naddrs = append(naddrs, addr)
+ case *UDPAddr:
+ if !wildcard && !addr.isWildcard() && !addr.IP.matchAddrFamily(udp.IP) {
+ continue
+ }
+ naddrs = append(naddrs, addr)
+ case *IPAddr:
+ if !wildcard && !addr.isWildcard() && !addr.IP.matchAddrFamily(ip.IP) {
+ continue
+ }
+ naddrs = append(naddrs, addr)
+ }
+ }
+ if len(naddrs) == 0 {
+ return nil, &AddrError{Err: errNoSuitableAddress.Error(), Addr: hint.String()}
+ }
+ return naddrs, nil
+}
+
+// MultipathTCP reports whether MPTCP will be used.
+//
+// This method doesn't check if MPTCP is supported by the operating
+// system or not.
+func (d *Dialer) MultipathTCP() bool {
+ return d.mptcpStatus.get()
+}
+
+// SetMultipathTCP directs the [Dial] methods to use, or not use, MPTCP,
+// if supported by the operating system. This method overrides the
+// system default and the GODEBUG=multipathtcp=... setting if any.
+//
+// If MPTCP is not available on the host or not supported by the server,
+// the Dial methods will fall back to TCP.
+func (d *Dialer) SetMultipathTCP(use bool) {
+ d.mptcpStatus.set(use)
+}
+
+// Dial connects to the address on the named network.
+//
+// Known networks are "tcp", "tcp4" (IPv4-only), "tcp6" (IPv6-only),
+// "udp", "udp4" (IPv4-only), "udp6" (IPv6-only), "ip", "ip4"
+// (IPv4-only), "ip6" (IPv6-only), "unix", "unixgram" and
+// "unixpacket".
+//
+// For TCP and UDP networks, the address has the form "host:port".
+// The host must be a literal IP address, or a host name that can be
+// resolved to IP addresses.
+// The port must be a literal port number or a service name.
+// If the host is a literal IPv6 address it must be enclosed in square
+// brackets, as in "[2001:db8::1]:80" or "[fe80::1%zone]:80".
+// The zone specifies the scope of the literal IPv6 address as defined
+// in RFC 4007.
+// The functions [JoinHostPort] and [SplitHostPort] manipulate a pair of
+// host and port in this form.
+// When using TCP, and the host resolves to multiple IP addresses,
+// Dial will try each IP address in order until one succeeds.
+//
+// Examples:
+//
+// Dial("tcp", "golang.org:http")
+// Dial("tcp", "192.0.2.1:http")
+// Dial("tcp", "198.51.100.1:80")
+// Dial("udp", "[2001:db8::1]:domain")
+// Dial("udp", "[fe80::1%lo0]:53")
+// Dial("tcp", ":80")
+//
+// For IP networks, the network must be "ip", "ip4" or "ip6" followed
+// by a colon and a literal protocol number or a protocol name, and
+// the address has the form "host". The host must be a literal IP
+// address or a literal IPv6 address with zone.
+// It depends on each operating system how the operating system
+// behaves with a non-well known protocol number such as "0" or "255".
+//
+// Examples:
+//
+// Dial("ip4:1", "192.0.2.1")
+// Dial("ip6:ipv6-icmp", "2001:db8::1")
+// Dial("ip6:58", "fe80::1%lo0")
+//
+// For TCP, UDP and IP networks, if the host is empty or a literal
+// unspecified IP address, as in ":80", "0.0.0.0:80" or "[::]:80" for
+// TCP and UDP, "", "0.0.0.0" or "::" for IP, the local system is
+// assumed.
+//
+// For Unix networks, the address must be a file system path.
+func Dial(network, address string) (Conn, error) {
+ var d Dialer
+ return d.Dial(network, address)
+}
+
+// DialTimeout acts like [Dial] but takes a timeout.
+//
+// The timeout includes name resolution, if required.
+// When using TCP, and the host in the address parameter resolves to
+// multiple IP addresses, the timeout is spread over each consecutive
+// dial, such that each is given an appropriate fraction of the time
+// to connect.
+//
+// See func Dial for a description of the network and address
+// parameters.
+func DialTimeout(network, address string, timeout time.Duration) (Conn, error) {
+ d := Dialer{Timeout: timeout}
+ return d.Dial(network, address)
+}
+
+// sysDialer contains a Dial's parameters and configuration.
+type sysDialer struct {
+ Dialer
+ network, address string
+ testHookDialTCP func(ctx context.Context, net string, laddr, raddr *TCPAddr) (*TCPConn, error)
+}
+
+// Dial connects to the address on the named network.
+//
+// See func Dial for a description of the network and address
+// parameters.
+//
+// Dial uses [context.Background] internally; to specify the context, use
+// [Dialer.DialContext].
+func (d *Dialer) Dial(network, address string) (Conn, error) {
+ return d.DialContext(context.Background(), network, address)
+}
+
+// DialContext connects to the address on the named network using
+// the provided context.
+//
+// The provided Context must be non-nil. If the context expires before
+// the connection is complete, an error is returned. Once successfully
+// connected, any expiration of the context will not affect the
+// connection.
+//
+// When using TCP, and the host in the address parameter resolves to multiple
+// network addresses, any dial timeout (from d.Timeout or ctx) is spread
+// over each consecutive dial, such that each is given an appropriate
+// fraction of the time to connect.
+// For example, if a host has 4 IP addresses and the timeout is 1 minute,
+// the connect to each single address will be given 15 seconds to complete
+// before trying the next one.
+//
+// See func [Dial] for a description of the network and address
+// parameters.
+func (d *Dialer) DialContext(ctx context.Context, network, address string) (Conn, error) {
+ ctx, cancel := d.dialCtx(ctx)
+ defer cancel()
+
+ // Shadow the nettrace (if any) during resolve so Connect events don't fire for DNS lookups.
+ resolveCtx := ctx
+ if trace, _ := ctx.Value(nettrace.TraceKey{}).(*nettrace.Trace); trace != nil {
+ shadow := *trace
+ shadow.ConnectStart = nil
+ shadow.ConnectDone = nil
+ resolveCtx = context.WithValue(resolveCtx, nettrace.TraceKey{}, &shadow)
+ }
+
+ addrs, err := d.resolver().resolveAddrList(resolveCtx, "dial", network, address, d.LocalAddr)
+ if err != nil {
+ return nil, &OpError{Op: "dial", Net: network, Source: nil, Addr: nil, Err: err}
+ }
+
+ sd := &sysDialer{
+ Dialer: *d,
+ network: network,
+ address: address,
+ }
+
+ var primaries, fallbacks addrList
+ if d.dualStack() && network == "tcp" {
+ primaries, fallbacks = addrs.partition(isIPv4)
+ } else {
+ primaries = addrs
+ }
+
+ return sd.dialParallel(ctx, primaries, fallbacks)
+}
+
+func (d *Dialer) dialCtx(ctx context.Context) (context.Context, context.CancelFunc) {
+ if ctx == nil {
+ panic("nil context")
+ }
+ deadline := d.deadline(ctx, time.Now())
+ var cancel1, cancel2 context.CancelFunc
+ if !deadline.IsZero() {
+ testHookStepTime()
+ if d, ok := ctx.Deadline(); !ok || deadline.Before(d) {
+ var subCtx context.Context
+ subCtx, cancel1 = context.WithDeadline(ctx, deadline)
+ ctx = subCtx
+ }
+ }
+ if oldCancel := d.Cancel; oldCancel != nil {
+ subCtx, cancel2 := context.WithCancel(ctx)
+ go func() {
+ select {
+ case <-oldCancel:
+ cancel2()
+ case <-subCtx.Done():
+ }
+ }()
+ ctx = subCtx
+ }
+ return ctx, func() {
+ if cancel1 != nil {
+ cancel1()
+ }
+ if cancel2 != nil {
+ cancel2()
+ }
+ }
+}
+
+// DialTCP acts like Dial for TCP networks using the provided context.
+//
+// The provided Context must be non-nil. If the context expires before
+// the connection is complete, an error is returned. Once successfully
+// connected, any expiration of the context will not affect the
+// connection.
+//
+// The network must be a TCP network name; see func Dial for details.
+func (d *Dialer) DialTCP(ctx context.Context, network string, laddr netip.AddrPort, raddr netip.AddrPort) (*TCPConn, error) {
+ ctx, cancel := d.dialCtx(ctx)
+ defer cancel()
+ return dialTCP(ctx, d, network, TCPAddrFromAddrPort(laddr), TCPAddrFromAddrPort(raddr))
+}
+
+// DialUDP acts like Dial for UDP networks using the provided context.
+//
+// The provided Context must be non-nil. If the context expires before
+// the connection is complete, an error is returned. Once successfully
+// connected, any expiration of the context will not affect the
+// connection.
+//
+// The network must be a UDP network name; see func Dial for details.
+func (d *Dialer) DialUDP(ctx context.Context, network string, laddr netip.AddrPort, raddr netip.AddrPort) (*UDPConn, error) {
+ ctx, cancel := d.dialCtx(ctx)
+ defer cancel()
+ return dialUDP(ctx, d, network, UDPAddrFromAddrPort(laddr), UDPAddrFromAddrPort(raddr))
+}
+
+// DialIP acts like Dial for IP networks using the provided context.
+//
+// The provided Context must be non-nil. If the context expires before
+// the connection is complete, an error is returned. Once successfully
+// connected, any expiration of the context will not affect the
+// connection.
+//
+// The network must be an IP network name; see func Dial for details.
+func (d *Dialer) DialIP(ctx context.Context, network string, laddr netip.Addr, raddr netip.Addr) (*IPConn, error) {
+ ctx, cancel := d.dialCtx(ctx)
+ defer cancel()
+ return dialIP(ctx, d, network, ipAddrFromAddr(laddr), ipAddrFromAddr(raddr))
+}
+
+// DialUnix acts like Dial for Unix networks using the provided context.
+//
+// The provided Context must be non-nil. If the context expires before
+// the connection is complete, an error is returned. Once successfully
+// connected, any expiration of the context will not affect the
+// connection.
+//
+// The network must be a Unix network name; see func Dial for details.
+func (d *Dialer) DialUnix(ctx context.Context, network string, laddr *UnixAddr, raddr *UnixAddr) (*UnixConn, error) {
+ ctx, cancel := d.dialCtx(ctx)
+ defer cancel()
+ return dialUnix(ctx, d, network, laddr, raddr)
+}
+
+// dialParallel races two copies of dialSerial, giving the first a
+// head start. It returns the first established connection and
+// closes the others. Otherwise it returns an error from the first
+// primary address.
+func (sd *sysDialer) dialParallel(ctx context.Context, primaries, fallbacks addrList) (Conn, error) {
+ if len(fallbacks) == 0 {
+ return sd.dialSerial(ctx, primaries)
+ }
+
+ returned := make(chan struct{})
+ defer close(returned)
+
+ type dialResult struct {
+ Conn
+ error
+ primary bool
+ done bool
+ }
+ results := make(chan dialResult) // unbuffered
+
+ startRacer := func(ctx context.Context, primary bool) {
+ ras := primaries
+ if !primary {
+ ras = fallbacks
+ }
+ c, err := sd.dialSerial(ctx, ras)
+ select {
+ case results <- dialResult{Conn: c, error: err, primary: primary, done: true}:
+ case <-returned:
+ if c != nil {
+ c.Close()
+ }
+ }
+ }
+
+ var primary, fallback dialResult
+
+ // Start the main racer.
+ primaryCtx, primaryCancel := context.WithCancel(ctx)
+ defer primaryCancel()
+ go startRacer(primaryCtx, true)
+
+ // Start the timer for the fallback racer.
+ fallbackTimer := time.NewTimer(sd.fallbackDelay())
+ defer fallbackTimer.Stop()
+
+ for {
+ select {
+ case <-fallbackTimer.C:
+ fallbackCtx, fallbackCancel := context.WithCancel(ctx)
+ defer fallbackCancel()
+ go startRacer(fallbackCtx, false)
+
+ case res := <-results:
+ if res.error == nil {
+ return res.Conn, nil
+ }
+ if res.primary {
+ primary = res
+ } else {
+ fallback = res
+ }
+ if primary.done && fallback.done {
+ return nil, primary.error
+ }
+ if res.primary && fallbackTimer.Stop() {
+ // If we were able to stop the timer, that means it
+ // was running (hadn't yet started the fallback), but
+ // we just got an error on the primary path, so start
+ // the fallback immediately (in 0 nanoseconds).
+ fallbackTimer.Reset(0)
+ }
+ }
+ }
+}
+
+// dialSerial connects to a list of addresses in sequence, returning
+// either the first successful connection, or the first error.
+func (sd *sysDialer) dialSerial(ctx context.Context, ras addrList) (Conn, error) {
+ var firstErr error // The error from the first address is most relevant.
+
+ for i, ra := range ras {
+ select {
+ case <-ctx.Done():
+ return nil, &OpError{Op: "dial", Net: sd.network, Source: sd.LocalAddr, Addr: ra, Err: mapErr(ctx.Err())}
+ default:
+ }
+
+ dialCtx := ctx
+ if deadline, hasDeadline := ctx.Deadline(); hasDeadline {
+ partialDeadline, err := partialDeadline(time.Now(), deadline, len(ras)-i)
+ if err != nil {
+ // Ran out of time.
+ if firstErr == nil {
+ firstErr = &OpError{Op: "dial", Net: sd.network, Source: sd.LocalAddr, Addr: ra, Err: err}
+ }
+ break
+ }
+ if partialDeadline.Before(deadline) {
+ var cancel context.CancelFunc
+ dialCtx, cancel = context.WithDeadline(ctx, partialDeadline)
+ defer cancel()
+ }
+ }
+
+ c, err := sd.dialSingle(dialCtx, ra)
+ if err == nil {
+ return c, nil
+ }
+ if firstErr == nil {
+ firstErr = err
+ }
+ }
+
+ if firstErr == nil {
+ firstErr = &OpError{Op: "dial", Net: sd.network, Source: nil, Addr: nil, Err: errMissingAddress}
+ }
+ return nil, firstErr
+}
+
+// dialSingle attempts to establish and returns a single connection to
+// the destination address.
+func (sd *sysDialer) dialSingle(ctx context.Context, ra Addr) (c Conn, err error) {
+ trace, _ := ctx.Value(nettrace.TraceKey{}).(*nettrace.Trace)
+ if trace != nil {
+ raStr := ra.String()
+ if trace.ConnectStart != nil {
+ trace.ConnectStart(sd.network, raStr)
+ }
+ if trace.ConnectDone != nil {
+ defer func() { trace.ConnectDone(sd.network, raStr, err) }()
+ }
+ }
+ la := sd.LocalAddr
+ switch ra := ra.(type) {
+ case *TCPAddr:
+ la, _ := la.(*TCPAddr)
+ if sd.MultipathTCP() {
+ c, err = sd.dialMPTCP(ctx, la, ra)
+ } else {
+ c, err = sd.dialTCP(ctx, la, ra)
+ }
+ case *UDPAddr:
+ la, _ := la.(*UDPAddr)
+ c, err = sd.dialUDP(ctx, la, ra)
+ case *IPAddr:
+ la, _ := la.(*IPAddr)
+ c, err = sd.dialIP(ctx, la, ra)
+ case *UnixAddr:
+ la, _ := la.(*UnixAddr)
+ c, err = sd.dialUnix(ctx, la, ra)
+ default:
+ return nil, &OpError{Op: "dial", Net: sd.network, Source: la, Addr: ra, Err: &AddrError{Err: "unexpected address type", Addr: sd.address}}
+ }
+ if err != nil {
+ return nil, &OpError{Op: "dial", Net: sd.network, Source: la, Addr: ra, Err: err} // c is non-nil interface containing nil pointer
+ }
+ return c, nil
+}
+
+// ListenConfig contains options for listening to an address.
+type ListenConfig struct {
+ // If Control is not nil, it is called after creating the network
+ // connection but before binding it to the operating system.
+ //
+ // Network and address parameters passed to Control function are not
+ // necessarily the ones passed to Listen. Calling Listen with TCP networks
+ // will cause the Control function to be called with "tcp4" or "tcp6",
+ // UDP networks become "udp4" or "udp6", IP networks become "ip4" or "ip6",
+ // and other known networks are passed as-is.
+ Control func(network, address string, c syscall.RawConn) error
+
+ // KeepAlive specifies the keep-alive period for network
+ // connections accepted by this listener.
+ //
+ // KeepAlive is ignored if KeepAliveConfig.Enable is true.
+ //
+ // If zero, keep-alive are enabled if supported by the protocol
+ // and operating system. Network protocols or operating systems
+ // that do not support keep-alive ignore this field.
+ // If negative, keep-alive are disabled.
+ KeepAlive time.Duration
+
+ // KeepAliveConfig specifies the keep-alive probe configuration
+ // for an active network connection, when supported by the
+ // protocol and operating system.
+ //
+ // If KeepAliveConfig.Enable is true, keep-alive probes are enabled.
+ // If KeepAliveConfig.Enable is false and KeepAlive is negative,
+ // keep-alive probes are disabled.
+ KeepAliveConfig KeepAliveConfig
+
+ // If mptcpStatus is set to a value allowing Multipath TCP (MPTCP) to be
+ // used, any call to Listen with "tcp(4|6)" as network will use MPTCP if
+ // supported by the operating system.
+ mptcpStatus mptcpStatusListen
+}
+
+// MultipathTCP reports whether MPTCP will be used.
+//
+// This method doesn't check if MPTCP is supported by the operating
+// system or not.
+func (lc *ListenConfig) MultipathTCP() bool {
+ return lc.mptcpStatus.get()
+}
+
+// SetMultipathTCP directs the [Listen] method to use, or not use, MPTCP,
+// if supported by the operating system. This method overrides the
+// system default and the GODEBUG=multipathtcp=... setting if any.
+//
+// If MPTCP is not available on the host or not supported by the client,
+// the Listen method will fall back to TCP.
+func (lc *ListenConfig) SetMultipathTCP(use bool) {
+ lc.mptcpStatus.set(use)
+}
+
+// Listen announces on the local network address.
+//
+// See func Listen for a description of the network and address
+// parameters.
+//
+// The ctx argument is used while resolving the address on which to listen;
+// it does not affect the returned Listener.
+func (lc *ListenConfig) Listen(ctx context.Context, network, address string) (Listener, error) {
+ addrs, err := DefaultResolver.resolveAddrList(ctx, "listen", network, address, nil)
+ if err != nil {
+ return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: nil, Err: err}
+ }
+ sl := &sysListener{
+ ListenConfig: *lc,
+ network: network,
+ address: address,
+ }
+ var l Listener
+ la := addrs.first(isIPv4)
+ switch la := la.(type) {
+ case *TCPAddr:
+ if sl.MultipathTCP() {
+ l, err = sl.listenMPTCP(ctx, la)
+ } else {
+ l, err = sl.listenTCP(ctx, la)
+ }
+ case *UnixAddr:
+ l, err = sl.listenUnix(ctx, la)
+ default:
+ return nil, &OpError{Op: "listen", Net: sl.network, Source: nil, Addr: la, Err: &AddrError{Err: "unexpected address type", Addr: address}}
+ }
+ if err != nil {
+ return nil, &OpError{Op: "listen", Net: sl.network, Source: nil, Addr: la, Err: err} // l is non-nil interface containing nil pointer
+ }
+ return l, nil
+}
+
+// ListenPacket announces on the local network address.
+//
+// See func ListenPacket for a description of the network and address
+// parameters.
+//
+// The ctx argument is used while resolving the address on which to listen;
+// it does not affect the returned PacketConn.
+func (lc *ListenConfig) ListenPacket(ctx context.Context, network, address string) (PacketConn, error) {
+ addrs, err := DefaultResolver.resolveAddrList(ctx, "listen", network, address, nil)
+ if err != nil {
+ return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: nil, Err: err}
+ }
+ sl := &sysListener{
+ ListenConfig: *lc,
+ network: network,
+ address: address,
+ }
+ var c PacketConn
+ la := addrs.first(isIPv4)
+ switch la := la.(type) {
+ case *UDPAddr:
+ c, err = sl.listenUDP(ctx, la)
+ case *IPAddr:
+ c, err = sl.listenIP(ctx, la)
+ case *UnixAddr:
+ c, err = sl.listenUnixgram(ctx, la)
+ default:
+ return nil, &OpError{Op: "listen", Net: sl.network, Source: nil, Addr: la, Err: &AddrError{Err: "unexpected address type", Addr: address}}
+ }
+ if err != nil {
+ return nil, &OpError{Op: "listen", Net: sl.network, Source: nil, Addr: la, Err: err} // c is non-nil interface containing nil pointer
+ }
+ return c, nil
+}
+
+// sysListener contains a Listen's parameters and configuration.
+type sysListener struct {
+ ListenConfig
+ network, address string
+}
+
+// Listen announces on the local network address.
+//
+// The network must be "tcp", "tcp4", "tcp6", "unix" or "unixpacket".
+//
+// For TCP networks, if the host in the address parameter is empty or
+// a literal unspecified IP address, Listen listens on all available
+// unicast and anycast IP addresses of the local system.
+// To only use IPv4, use network "tcp4".
+// The address can use a host name, but this is not recommended,
+// because it will create a listener for at most one of the host's IP
+// addresses.
+// If the port in the address parameter is empty or "0", as in
+// "127.0.0.1:" or "[::1]:0", a port number is automatically chosen.
+// The [Addr] method of [Listener] can be used to discover the chosen
+// port.
+//
+// See func [Dial] for a description of the network and address
+// parameters.
+//
+// Listen uses context.Background internally; to specify the context, use
+// [ListenConfig.Listen].
+func Listen(network, address string) (Listener, error) {
+ var lc ListenConfig
+ return lc.Listen(context.Background(), network, address)
+}
+
+// ListenPacket announces on the local network address.
+//
+// The network must be "udp", "udp4", "udp6", "unixgram", or an IP
+// transport. The IP transports are "ip", "ip4", or "ip6" followed by
+// a colon and a literal protocol number or a protocol name, as in
+// "ip:1" or "ip:icmp".
+//
+// For UDP and IP networks, if the host in the address parameter is
+// empty or a literal unspecified IP address, ListenPacket listens on
+// all available IP addresses of the local system except multicast IP
+// addresses.
+// To only use IPv4, use network "udp4" or "ip4:proto".
+// The address can use a host name, but this is not recommended,
+// because it will create a listener for at most one of the host's IP
+// addresses.
+// If the port in the address parameter is empty or "0", as in
+// "127.0.0.1:" or "[::1]:0", a port number is automatically chosen.
+// The LocalAddr method of [PacketConn] can be used to discover the
+// chosen port.
+//
+// See func [Dial] for a description of the network and address
+// parameters.
+//
+// ListenPacket uses context.Background internally; to specify the context, use
+// [ListenConfig.ListenPacket].
+func ListenPacket(network, address string) (PacketConn, error) {
+ var lc ListenConfig
+ return lc.ListenPacket(context.Background(), network, address)
+}
diff --git a/go/src/net/dial_test.go b/go/src/net/dial_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..07a9b46ddb69ef450a8502c159d5418c2dad7cdb
--- /dev/null
+++ b/go/src/net/dial_test.go
@@ -0,0 +1,1202 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "bufio"
+ "context"
+ "errors"
+ "fmt"
+ "internal/testenv"
+ "io"
+ "net/netip"
+ "os"
+ "runtime"
+ "strings"
+ "sync"
+ "syscall"
+ "testing"
+ "time"
+)
+
+var prohibitionaryDialArgTests = []struct {
+ network string
+ address string
+}{
+ {"tcp6", "127.0.0.1"},
+ {"tcp6", "::ffff:127.0.0.1"},
+}
+
+func TestProhibitionaryDialArg(t *testing.T) {
+ testenv.MustHaveExternalNetwork(t)
+
+ switch runtime.GOOS {
+ case "plan9":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+ if !supportsIPv4map() {
+ t.Skip("mapping ipv4 address inside ipv6 address not supported")
+ }
+
+ ln, err := Listen("tcp", "[::]:0")
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer ln.Close()
+
+ _, port, err := SplitHostPort(ln.Addr().String())
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ for i, tt := range prohibitionaryDialArgTests {
+ c, err := Dial(tt.network, JoinHostPort(tt.address, port))
+ if err == nil {
+ c.Close()
+ t.Errorf("#%d: %v", i, err)
+ }
+ }
+}
+
+func TestDialLocal(t *testing.T) {
+ ln := newLocalListener(t, "tcp")
+ defer ln.Close()
+ _, port, err := SplitHostPort(ln.Addr().String())
+ if err != nil {
+ t.Fatal(err)
+ }
+ c, err := Dial("tcp", JoinHostPort("", port))
+ if err != nil {
+ t.Fatal(err)
+ }
+ c.Close()
+}
+
+func TestDialerDualStackFDLeak(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9":
+ t.Skipf("%s does not have full support of socktest", runtime.GOOS)
+ case "windows":
+ t.Skipf("not implemented a way to cancel dial racers in TCP SYN-SENT state on %s", runtime.GOOS)
+ case "openbsd":
+ testenv.SkipFlaky(t, 15157)
+ }
+ if !supportsIPv4() || !supportsIPv6() {
+ t.Skip("both IPv4 and IPv6 are required")
+ }
+
+ before := sw.Sockets()
+ origTestHookLookupIP := testHookLookupIP
+ defer func() { testHookLookupIP = origTestHookLookupIP }()
+ testHookLookupIP = lookupLocalhost
+ handler := func(dss *dualStackServer, ln Listener) {
+ for {
+ c, err := ln.Accept()
+ if err != nil {
+ return
+ }
+ c.Close()
+ }
+ }
+ dss, err := newDualStackServer()
+ if err != nil {
+ t.Fatal(err)
+ }
+ if err := dss.buildup(handler); err != nil {
+ dss.teardown()
+ t.Fatal(err)
+ }
+
+ const N = 10
+ var wg sync.WaitGroup
+ wg.Add(N)
+ d := &Dialer{DualStack: true, Timeout: 5 * time.Second}
+ for i := 0; i < N; i++ {
+ go func() {
+ defer wg.Done()
+ c, err := d.Dial("tcp", JoinHostPort("localhost", dss.port))
+ if err != nil {
+ t.Error(err)
+ return
+ }
+ c.Close()
+ }()
+ }
+ wg.Wait()
+ dss.teardown()
+ after := sw.Sockets()
+ if len(after) != len(before) {
+ t.Errorf("got %d; want %d", len(after), len(before))
+ }
+}
+
+// Define a pair of blackholed (IPv4, IPv6) addresses, for which dialTCP is
+// expected to hang until the timeout elapses. These addresses are reserved
+// for benchmarking by RFC 6890.
+const (
+ slowDst4 = "198.18.0.254"
+ slowDst6 = "2001:2::254"
+)
+
+// In some environments, the slow IPs may be explicitly unreachable, and fail
+// more quickly than expected. This test hook prevents dialTCP from returning
+// before the deadline.
+func slowDialTCP(ctx context.Context, network string, laddr, raddr *TCPAddr) (*TCPConn, error) {
+ sd := &sysDialer{network: network, address: raddr.String()}
+ c, err := sd.doDialTCP(ctx, laddr, raddr)
+ if ParseIP(slowDst4).Equal(raddr.IP) || ParseIP(slowDst6).Equal(raddr.IP) {
+ // Wait for the deadline, or indefinitely if none exists.
+ <-ctx.Done()
+ }
+ return c, err
+}
+
+func dialClosedPort(t *testing.T) (dialLatency time.Duration) {
+ // On most platforms, dialing a closed port should be nearly instantaneous —
+ // less than a few hundred milliseconds. However, on some platforms it may be
+ // much slower: on Windows and OpenBSD, it has been observed to take up to a
+ // few seconds.
+
+ l, err := Listen("tcp", "127.0.0.1:0")
+ if err != nil {
+ t.Fatalf("dialClosedPort: Listen failed: %v", err)
+ }
+ addr := l.Addr().String()
+ l.Close()
+
+ startTime := time.Now()
+ c, err := Dial("tcp", addr)
+ if err == nil {
+ c.Close()
+ }
+ elapsed := time.Since(startTime)
+ t.Logf("dialClosedPort: measured delay %v", elapsed)
+ return elapsed
+}
+
+func TestDialParallel(t *testing.T) {
+ const instant time.Duration = 0
+ const fallbackDelay = 200 * time.Millisecond
+
+ nCopies := func(s string, n int) []string {
+ out := make([]string, n)
+ for i := 0; i < n; i++ {
+ out[i] = s
+ }
+ return out
+ }
+
+ var testCases = []struct {
+ primaries []string
+ fallbacks []string
+ teardownNetwork string
+ expectOk bool
+ expectElapsed time.Duration
+ }{
+ // These should just work on the first try.
+ {[]string{"127.0.0.1"}, []string{}, "", true, instant},
+ {[]string{"::1"}, []string{}, "", true, instant},
+ {[]string{"127.0.0.1", "::1"}, []string{slowDst6}, "tcp6", true, instant},
+ {[]string{"::1", "127.0.0.1"}, []string{slowDst4}, "tcp4", true, instant},
+ // Primary is slow; fallback should kick in.
+ {[]string{slowDst4}, []string{"::1"}, "", true, fallbackDelay},
+ // Skip a "connection refused" in the primary thread.
+ {[]string{"127.0.0.1", "::1"}, []string{}, "tcp4", true, instant},
+ {[]string{"::1", "127.0.0.1"}, []string{}, "tcp6", true, instant},
+ // Skip a "connection refused" in the fallback thread.
+ {[]string{slowDst4, slowDst6}, []string{"::1", "127.0.0.1"}, "tcp6", true, fallbackDelay},
+ // Primary refused, fallback without delay.
+ {[]string{"127.0.0.1"}, []string{"::1"}, "tcp4", true, instant},
+ {[]string{"::1"}, []string{"127.0.0.1"}, "tcp6", true, instant},
+ // Everything is refused.
+ {[]string{"127.0.0.1"}, []string{}, "tcp4", false, instant},
+ // Nothing to do; fail instantly.
+ {[]string{}, []string{}, "", false, instant},
+ // Connecting to tons of addresses should not trip the deadline.
+ {nCopies("::1", 1000), []string{}, "", true, instant},
+ }
+
+ // Convert a list of IP strings into TCPAddrs.
+ makeAddrs := func(ips []string, port string) addrList {
+ var out addrList
+ for _, ip := range ips {
+ addr, err := ResolveTCPAddr("tcp", JoinHostPort(ip, port))
+ if err != nil {
+ t.Fatal(err)
+ }
+ out = append(out, addr)
+ }
+ return out
+ }
+
+ for i, tt := range testCases {
+ t.Run(fmt.Sprint(i), func(t *testing.T) {
+ dialTCP := func(ctx context.Context, network string, laddr, raddr *TCPAddr) (*TCPConn, error) {
+ n := "tcp6"
+ if raddr.IP.To4() != nil {
+ n = "tcp4"
+ }
+ if n == tt.teardownNetwork {
+ return nil, errors.New("unreachable")
+ }
+ if r := raddr.IP.String(); r == slowDst4 || r == slowDst6 {
+ <-ctx.Done()
+ return nil, ctx.Err()
+ }
+ return &TCPConn{}, nil
+ }
+
+ primaries := makeAddrs(tt.primaries, "80")
+ fallbacks := makeAddrs(tt.fallbacks, "80")
+ d := Dialer{
+ FallbackDelay: fallbackDelay,
+ }
+ const forever = 60 * time.Minute
+ if tt.expectElapsed == instant {
+ d.FallbackDelay = forever
+ }
+ startTime := time.Now()
+ sd := &sysDialer{
+ Dialer: d,
+ network: "tcp",
+ address: "?",
+ testHookDialTCP: dialTCP,
+ }
+ c, err := sd.dialParallel(context.Background(), primaries, fallbacks)
+ elapsed := time.Since(startTime)
+
+ if c != nil {
+ c.Close()
+ }
+
+ if tt.expectOk && err != nil {
+ t.Errorf("#%d: got %v; want nil", i, err)
+ } else if !tt.expectOk && err == nil {
+ t.Errorf("#%d: got nil; want non-nil", i)
+ }
+
+ if elapsed < tt.expectElapsed || elapsed >= forever {
+ t.Errorf("#%d: got %v; want >= %v, < forever", i, elapsed, tt.expectElapsed)
+ }
+
+ // Repeat each case, ensuring that it can be canceled.
+ ctx, cancel := context.WithCancel(context.Background())
+ var wg sync.WaitGroup
+ wg.Add(1)
+ go func() {
+ time.Sleep(5 * time.Millisecond)
+ cancel()
+ wg.Done()
+ }()
+ // Ignore errors, since all we care about is that the
+ // call can be canceled.
+ c, _ = sd.dialParallel(ctx, primaries, fallbacks)
+ if c != nil {
+ c.Close()
+ }
+ wg.Wait()
+ })
+ }
+}
+
+func lookupSlowFast(ctx context.Context, fn func(context.Context, string, string) ([]IPAddr, error), network, host string) ([]IPAddr, error) {
+ switch host {
+ case "slow6loopback4":
+ // Returns a slow IPv6 address, and a local IPv4 address.
+ return []IPAddr{
+ {IP: ParseIP(slowDst6)},
+ {IP: ParseIP("127.0.0.1")},
+ }, nil
+ default:
+ return fn(ctx, network, host)
+ }
+}
+
+func TestDialerFallbackDelay(t *testing.T) {
+ testenv.MustHaveExternalNetwork(t)
+
+ if !supportsIPv4() || !supportsIPv6() {
+ t.Skip("both IPv4 and IPv6 are required")
+ }
+
+ origTestHookLookupIP := testHookLookupIP
+ defer func() { testHookLookupIP = origTestHookLookupIP }()
+ testHookLookupIP = lookupSlowFast
+
+ origTestHookDialTCP := testHookDialTCP
+ defer func() { testHookDialTCP = origTestHookDialTCP }()
+ testHookDialTCP = slowDialTCP
+
+ var testCases = []struct {
+ dualstack bool
+ delay time.Duration
+ expectElapsed time.Duration
+ }{
+ // Use a very brief delay, which should fallback immediately.
+ {true, 1 * time.Nanosecond, 0},
+ // Use a 200ms explicit timeout.
+ {true, 200 * time.Millisecond, 200 * time.Millisecond},
+ // The default is 300ms.
+ {true, 0, 300 * time.Millisecond},
+ }
+
+ handler := func(dss *dualStackServer, ln Listener) {
+ for {
+ c, err := ln.Accept()
+ if err != nil {
+ return
+ }
+ c.Close()
+ }
+ }
+ dss, err := newDualStackServer()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer dss.teardown()
+ if err := dss.buildup(handler); err != nil {
+ t.Fatal(err)
+ }
+
+ for i, tt := range testCases {
+ d := &Dialer{DualStack: tt.dualstack, FallbackDelay: tt.delay}
+
+ startTime := time.Now()
+ c, err := d.Dial("tcp", JoinHostPort("slow6loopback4", dss.port))
+ elapsed := time.Since(startTime)
+ if err == nil {
+ c.Close()
+ } else if tt.dualstack {
+ t.Error(err)
+ }
+ expectMin := tt.expectElapsed - 1*time.Millisecond
+ expectMax := tt.expectElapsed + 95*time.Millisecond
+ if elapsed < expectMin {
+ t.Errorf("#%d: got %v; want >= %v", i, elapsed, expectMin)
+ }
+ if elapsed > expectMax {
+ t.Errorf("#%d: got %v; want <= %v", i, elapsed, expectMax)
+ }
+ }
+}
+
+func TestDialParallelSpuriousConnection(t *testing.T) {
+ if !supportsIPv4() || !supportsIPv6() {
+ t.Skip("both IPv4 and IPv6 are required")
+ }
+
+ var readDeadline time.Time
+ if td, ok := t.Deadline(); ok {
+ const arbitraryCleanupMargin = 1 * time.Second
+ readDeadline = td.Add(-arbitraryCleanupMargin)
+ } else {
+ readDeadline = time.Now().Add(5 * time.Second)
+ }
+
+ var closed sync.WaitGroup
+ closed.Add(2)
+ handler := func(dss *dualStackServer, ln Listener) {
+ // Accept one connection per address.
+ c, err := ln.Accept()
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ // Workaround for https://go.dev/issue/37795.
+ // On arm64 macOS (current as of macOS 12.4),
+ // reading from a socket at the same time as the client
+ // is closing it occasionally hangs for 60 seconds before
+ // returning ECONNRESET. Sleep for a bit to give the
+ // socket time to close before trying to read from it.
+ if runtime.GOOS == "darwin" && runtime.GOARCH == "arm64" {
+ time.Sleep(10 * time.Millisecond)
+ }
+
+ // The client should close itself, without sending data.
+ c.SetReadDeadline(readDeadline)
+ var b [1]byte
+ if _, err := c.Read(b[:]); err != io.EOF {
+ t.Errorf("got %v; want %v", err, io.EOF)
+ }
+ c.Close()
+ closed.Done()
+ }
+ dss, err := newDualStackServer()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer dss.teardown()
+ if err := dss.buildup(handler); err != nil {
+ t.Fatal(err)
+ }
+
+ const fallbackDelay = 100 * time.Millisecond
+
+ var dialing sync.WaitGroup
+ dialing.Add(2)
+ origTestHookDialTCP := testHookDialTCP
+ defer func() { testHookDialTCP = origTestHookDialTCP }()
+ testHookDialTCP = func(ctx context.Context, net string, laddr, raddr *TCPAddr) (*TCPConn, error) {
+ // Wait until Happy Eyeballs kicks in and both connections are dialing,
+ // and inhibit cancellation.
+ // This forces dialParallel to juggle two successful connections.
+ dialing.Done()
+ dialing.Wait()
+
+ // Now ignore the provided context (which will be canceled) and use a
+ // different one to make sure this completes with a valid connection,
+ // which we hope to be closed below:
+ sd := &sysDialer{network: net, address: raddr.String()}
+ return sd.doDialTCP(context.Background(), laddr, raddr)
+ }
+
+ d := Dialer{
+ FallbackDelay: fallbackDelay,
+ }
+ sd := &sysDialer{
+ Dialer: d,
+ network: "tcp",
+ address: "?",
+ }
+
+ makeAddr := func(ip string) addrList {
+ addr, err := ResolveTCPAddr("tcp", JoinHostPort(ip, dss.port))
+ if err != nil {
+ t.Fatal(err)
+ }
+ return addrList{addr}
+ }
+
+ // dialParallel returns one connection (and closes the other.)
+ c, err := sd.dialParallel(context.Background(), makeAddr("127.0.0.1"), makeAddr("::1"))
+ if err != nil {
+ t.Fatal(err)
+ }
+ c.Close()
+
+ // The server should've seen both connections.
+ closed.Wait()
+}
+
+func TestDialerPartialDeadline(t *testing.T) {
+ now := time.Date(2000, time.January, 1, 0, 0, 0, 0, time.UTC)
+ var testCases = []struct {
+ now time.Time
+ deadline time.Time
+ addrs int
+ expectDeadline time.Time
+ expectErr error
+ }{
+ // Regular division.
+ {now, now.Add(12 * time.Second), 1, now.Add(12 * time.Second), nil},
+ {now, now.Add(12 * time.Second), 2, now.Add(6 * time.Second), nil},
+ {now, now.Add(12 * time.Second), 3, now.Add(4 * time.Second), nil},
+ // Bump against the 2-second sane minimum.
+ {now, now.Add(12 * time.Second), 999, now.Add(2 * time.Second), nil},
+ // Total available is now below the sane minimum.
+ {now, now.Add(1900 * time.Millisecond), 999, now.Add(1900 * time.Millisecond), nil},
+ // Null deadline.
+ {now, noDeadline, 1, noDeadline, nil},
+ // Step the clock forward and cross the deadline.
+ {now.Add(-1 * time.Millisecond), now, 1, now, nil},
+ {now.Add(0 * time.Millisecond), now, 1, noDeadline, errTimeout},
+ {now.Add(1 * time.Millisecond), now, 1, noDeadline, errTimeout},
+ }
+ for i, tt := range testCases {
+ deadline, err := partialDeadline(tt.now, tt.deadline, tt.addrs)
+ if err != tt.expectErr {
+ t.Errorf("#%d: got %v; want %v", i, err, tt.expectErr)
+ }
+ if !deadline.Equal(tt.expectDeadline) {
+ t.Errorf("#%d: got %v; want %v", i, deadline, tt.expectDeadline)
+ }
+ }
+}
+
+// isEADDRINUSE reports whether err is syscall.EADDRINUSE.
+var isEADDRINUSE = func(err error) bool { return false }
+
+func TestDialerLocalAddr(t *testing.T) {
+ if !supportsIPv4() || !supportsIPv6() {
+ t.Skip("both IPv4 and IPv6 are required")
+ }
+
+ type test struct {
+ network, raddr string
+ laddr Addr
+ error
+ }
+ var tests = []test{
+ {"tcp4", "127.0.0.1", nil, nil},
+ {"tcp4", "127.0.0.1", &TCPAddr{}, nil},
+ {"tcp4", "127.0.0.1", &TCPAddr{IP: ParseIP("0.0.0.0")}, nil},
+ {"tcp4", "127.0.0.1", &TCPAddr{IP: ParseIP("0.0.0.0").To4()}, nil},
+ {"tcp4", "127.0.0.1", &TCPAddr{IP: ParseIP("::")}, &AddrError{Err: "some error"}},
+ {"tcp4", "127.0.0.1", &TCPAddr{IP: ParseIP("127.0.0.1").To4()}, nil},
+ {"tcp4", "127.0.0.1", &TCPAddr{IP: ParseIP("127.0.0.1").To16()}, nil},
+ {"tcp4", "127.0.0.1", &TCPAddr{IP: IPv6loopback}, errNoSuitableAddress},
+ {"tcp4", "127.0.0.1", &UDPAddr{}, &AddrError{Err: "some error"}},
+ {"tcp4", "127.0.0.1", &UnixAddr{}, &AddrError{Err: "some error"}},
+
+ {"tcp6", "::1", nil, nil},
+ {"tcp6", "::1", &TCPAddr{}, nil},
+ {"tcp6", "::1", &TCPAddr{IP: ParseIP("0.0.0.0")}, nil},
+ {"tcp6", "::1", &TCPAddr{IP: ParseIP("0.0.0.0").To4()}, nil},
+ {"tcp6", "::1", &TCPAddr{IP: ParseIP("::")}, nil},
+ {"tcp6", "::1", &TCPAddr{IP: ParseIP("127.0.0.1").To4()}, errNoSuitableAddress},
+ {"tcp6", "::1", &TCPAddr{IP: ParseIP("127.0.0.1").To16()}, errNoSuitableAddress},
+ {"tcp6", "::1", &TCPAddr{IP: IPv6loopback}, nil},
+ {"tcp6", "::1", &UDPAddr{}, &AddrError{Err: "some error"}},
+ {"tcp6", "::1", &UnixAddr{}, &AddrError{Err: "some error"}},
+
+ {"tcp", "127.0.0.1", nil, nil},
+ {"tcp", "127.0.0.1", &TCPAddr{}, nil},
+ {"tcp", "127.0.0.1", &TCPAddr{IP: ParseIP("0.0.0.0")}, nil},
+ {"tcp", "127.0.0.1", &TCPAddr{IP: ParseIP("0.0.0.0").To4()}, nil},
+ {"tcp", "127.0.0.1", &TCPAddr{IP: ParseIP("127.0.0.1").To4()}, nil},
+ {"tcp", "127.0.0.1", &TCPAddr{IP: ParseIP("127.0.0.1").To16()}, nil},
+ {"tcp", "127.0.0.1", &TCPAddr{IP: IPv6loopback}, errNoSuitableAddress},
+ {"tcp", "127.0.0.1", &UDPAddr{}, &AddrError{Err: "some error"}},
+ {"tcp", "127.0.0.1", &UnixAddr{}, &AddrError{Err: "some error"}},
+
+ {"tcp", "::1", nil, nil},
+ {"tcp", "::1", &TCPAddr{}, nil},
+ {"tcp", "::1", &TCPAddr{IP: ParseIP("0.0.0.0")}, nil},
+ {"tcp", "::1", &TCPAddr{IP: ParseIP("0.0.0.0").To4()}, nil},
+ {"tcp", "::1", &TCPAddr{IP: ParseIP("::")}, nil},
+ {"tcp", "::1", &TCPAddr{IP: ParseIP("127.0.0.1").To4()}, errNoSuitableAddress},
+ {"tcp", "::1", &TCPAddr{IP: ParseIP("127.0.0.1").To16()}, errNoSuitableAddress},
+ {"tcp", "::1", &TCPAddr{IP: IPv6loopback}, nil},
+ {"tcp", "::1", &UDPAddr{}, &AddrError{Err: "some error"}},
+ {"tcp", "::1", &UnixAddr{}, &AddrError{Err: "some error"}},
+ }
+
+ issue34264Index := -1
+ if supportsIPv4map() {
+ issue34264Index = len(tests)
+ tests = append(tests, test{
+ "tcp", "127.0.0.1", &TCPAddr{IP: ParseIP("::")}, nil,
+ })
+ } else {
+ tests = append(tests, test{
+ "tcp", "127.0.0.1", &TCPAddr{IP: ParseIP("::")}, &AddrError{Err: "some error"},
+ })
+ }
+
+ origTestHookLookupIP := testHookLookupIP
+ defer func() { testHookLookupIP = origTestHookLookupIP }()
+ testHookLookupIP = lookupLocalhost
+ handler := func(ls *localServer, ln Listener) {
+ for {
+ c, err := ln.Accept()
+ if err != nil {
+ return
+ }
+ c.Close()
+ }
+ }
+ var lss [2]*localServer
+ for i, network := range []string{"tcp4", "tcp6"} {
+ lss[i] = newLocalServer(t, network)
+ defer lss[i].teardown()
+ if err := lss[i].buildup(handler); err != nil {
+ t.Fatal(err)
+ }
+ }
+
+ for i, tt := range tests {
+ d := &Dialer{LocalAddr: tt.laddr}
+ var addr string
+ ip := ParseIP(tt.raddr)
+ if ip.To4() != nil {
+ addr = lss[0].Listener.Addr().String()
+ }
+ if ip.To16() != nil && ip.To4() == nil {
+ addr = lss[1].Listener.Addr().String()
+ }
+ c, err := d.Dial(tt.network, addr)
+ if err == nil && tt.error != nil || err != nil && tt.error == nil {
+ if i == issue34264Index && runtime.GOOS == "freebsd" && isEADDRINUSE(err) {
+ // https://golang.org/issue/34264: FreeBSD through at least version 12.2
+ // has been observed to fail with EADDRINUSE when dialing from an IPv6
+ // local address to an IPv4 remote address.
+ t.Logf("%s %v->%s: got %v; want %v", tt.network, tt.laddr, tt.raddr, err, tt.error)
+ t.Logf("(spurious EADDRINUSE ignored on freebsd: see https://golang.org/issue/34264)")
+ } else {
+ t.Errorf("%s %v->%s: got %v; want %v", tt.network, tt.laddr, tt.raddr, err, tt.error)
+ }
+ }
+ if err != nil {
+ if perr := parseDialError(err); perr != nil {
+ t.Error(perr)
+ }
+ continue
+ }
+ c.Close()
+ }
+}
+
+func TestDialerDualStack(t *testing.T) {
+ testenv.SkipFlaky(t, 13324)
+
+ if !supportsIPv4() || !supportsIPv6() {
+ t.Skip("both IPv4 and IPv6 are required")
+ }
+
+ closedPortDelay := dialClosedPort(t)
+
+ origTestHookLookupIP := testHookLookupIP
+ defer func() { testHookLookupIP = origTestHookLookupIP }()
+ testHookLookupIP = lookupLocalhost
+ handler := func(dss *dualStackServer, ln Listener) {
+ for {
+ c, err := ln.Accept()
+ if err != nil {
+ return
+ }
+ c.Close()
+ }
+ }
+
+ var timeout = 150*time.Millisecond + closedPortDelay
+ for _, dualstack := range []bool{false, true} {
+ dss, err := newDualStackServer()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer dss.teardown()
+ if err := dss.buildup(handler); err != nil {
+ t.Fatal(err)
+ }
+
+ d := &Dialer{DualStack: dualstack, Timeout: timeout}
+ for range dss.lns {
+ c, err := d.Dial("tcp", JoinHostPort("localhost", dss.port))
+ if err != nil {
+ t.Error(err)
+ continue
+ }
+ switch addr := c.LocalAddr().(*TCPAddr); {
+ case addr.IP.To4() != nil:
+ dss.teardownNetwork("tcp4")
+ case addr.IP.To16() != nil && addr.IP.To4() == nil:
+ dss.teardownNetwork("tcp6")
+ }
+ c.Close()
+ }
+ }
+}
+
+func TestDialerKeepAlive(t *testing.T) {
+ t.Cleanup(func() {
+ testHookSetKeepAlive = func(KeepAliveConfig) {}
+ })
+
+ handler := func(ls *localServer, ln Listener) {
+ for {
+ c, err := ln.Accept()
+ if err != nil {
+ return
+ }
+ c.Close()
+ }
+ }
+ ln := newLocalListener(t, "tcp", &ListenConfig{
+ KeepAlive: -1, // prevent calling hook from accepting
+ })
+ ls := (&streamListener{Listener: ln}).newLocalServer()
+ defer ls.teardown()
+ if err := ls.buildup(handler); err != nil {
+ t.Fatal(err)
+ }
+
+ tests := []struct {
+ ka time.Duration
+ expected time.Duration
+ }{
+ {-1, -1},
+ {0, 0},
+ {5 * time.Second, 5 * time.Second},
+ {30 * time.Second, 30 * time.Second},
+ }
+
+ var got time.Duration = -1
+ testHookSetKeepAlive = func(cfg KeepAliveConfig) { got = cfg.Idle }
+
+ for _, test := range tests {
+ got = -1
+ d := Dialer{KeepAlive: test.ka}
+ c, err := d.Dial("tcp", ls.Listener.Addr().String())
+ if err != nil {
+ t.Fatal(err)
+ }
+ c.Close()
+ if got != test.expected {
+ t.Errorf("Dialer.KeepAlive = %v: SetKeepAlive set to %v, want %v", d.KeepAlive, got, test.expected)
+ }
+ }
+}
+
+func TestDialCancel(t *testing.T) {
+ mustHaveExternalNetwork(t)
+
+ blackholeIPPort := JoinHostPort(slowDst4, "1234")
+ if !supportsIPv4() {
+ blackholeIPPort = JoinHostPort(slowDst6, "1234")
+ }
+
+ ticker := time.NewTicker(10 * time.Millisecond)
+ defer ticker.Stop()
+
+ const cancelTick = 5 // the timer tick we cancel the dial at
+ const timeoutTick = 100
+
+ var d Dialer
+ cancel := make(chan struct{})
+ d.Cancel = cancel
+ errc := make(chan error, 1)
+ connc := make(chan Conn, 1)
+ go func() {
+ if c, err := d.Dial("tcp", blackholeIPPort); err != nil {
+ errc <- err
+ } else {
+ connc <- c
+ }
+ }()
+ ticks := 0
+ for {
+ select {
+ case <-ticker.C:
+ ticks++
+ if ticks == cancelTick {
+ close(cancel)
+ }
+ if ticks == timeoutTick {
+ t.Fatal("timeout waiting for dial to fail")
+ }
+ case c := <-connc:
+ c.Close()
+ t.Fatal("unexpected successful connection")
+ case err := <-errc:
+ if perr := parseDialError(err); perr != nil {
+ t.Error(perr)
+ }
+ if ticks < cancelTick {
+ // Using strings.Contains is ugly but
+ // may work on plan9 and windows.
+ ignorable := []string{
+ "connection refused",
+ "unreachable",
+ "no route to host",
+ "invalid argument",
+ }
+ e := err.Error()
+ for _, ignore := range ignorable {
+ if strings.Contains(e, ignore) {
+ t.Skipf("connection to %v failed fast with %v", blackholeIPPort, err)
+ }
+ }
+
+ t.Fatalf("dial error after %d ticks (%d before cancel sent): %v",
+ ticks, cancelTick-ticks, err)
+ }
+ if oe, ok := err.(*OpError); !ok || oe.Err != errCanceled {
+ t.Fatalf("dial error = %v (%T); want OpError with Err == errCanceled", err, err)
+ }
+ return // success.
+ }
+ }
+}
+
+func TestCancelAfterDial(t *testing.T) {
+ if testing.Short() {
+ t.Skip("avoiding time.Sleep")
+ }
+
+ ln := newLocalListener(t, "tcp")
+
+ var wg sync.WaitGroup
+ wg.Add(1)
+ defer func() {
+ ln.Close()
+ wg.Wait()
+ }()
+
+ // Echo back the first line of each incoming connection.
+ go func() {
+ for {
+ c, err := ln.Accept()
+ if err != nil {
+ break
+ }
+ rb := bufio.NewReader(c)
+ line, err := rb.ReadString('\n')
+ if err != nil {
+ t.Error(err)
+ c.Close()
+ continue
+ }
+ if _, err := c.Write([]byte(line)); err != nil {
+ t.Error(err)
+ }
+ c.Close()
+ }
+ wg.Done()
+ }()
+
+ try := func() {
+ cancel := make(chan struct{})
+ d := &Dialer{Cancel: cancel}
+ c, err := d.Dial("tcp", ln.Addr().String())
+
+ // Immediately after dialing, request cancellation and sleep.
+ // Before Issue 15078 was fixed, this would cause subsequent operations
+ // to fail with an i/o timeout roughly 50% of the time.
+ close(cancel)
+ time.Sleep(10 * time.Millisecond)
+
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer c.Close()
+
+ // Send some data to confirm that the connection is still alive.
+ const message = "echo!\n"
+ if _, err := c.Write([]byte(message)); err != nil {
+ t.Fatal(err)
+ }
+
+ // The server should echo the line, and close the connection.
+ rb := bufio.NewReader(c)
+ line, err := rb.ReadString('\n')
+ if err != nil {
+ t.Fatal(err)
+ }
+ if line != message {
+ t.Errorf("got %q; want %q", line, message)
+ }
+ if _, err := rb.ReadByte(); err != io.EOF {
+ t.Errorf("got %v; want %v", err, io.EOF)
+ }
+ }
+
+ // This bug manifested about 50% of the time, so try it a few times.
+ for i := 0; i < 10; i++ {
+ try()
+ }
+}
+
+func TestDialClosedPortFailFast(t *testing.T) {
+ if runtime.GOOS != "windows" {
+ // Reported by go.dev/issues/23366.
+ t.Skip("skipping windows only test")
+ }
+ for _, network := range []string{"tcp", "tcp4", "tcp6"} {
+ t.Run(network, func(t *testing.T) {
+ if !testableNetwork(network) {
+ t.Skipf("skipping: can't listen on %s", network)
+ }
+ // Reserve a local port till the end of the
+ // test by opening a listener and connecting to
+ // it using Dial.
+ ln := newLocalListener(t, network)
+ addr := ln.Addr().String()
+ conn1, err := Dial(network, addr)
+ if err != nil {
+ ln.Close()
+ t.Fatal(err)
+ }
+ defer conn1.Close()
+ // Now close the listener so the next Dial fails
+ // keeping conn1 alive so the port is not made
+ // available.
+ ln.Close()
+
+ maxElapsed := time.Second
+ // The host can be heavy-loaded and take
+ // longer than configured. Retry until
+ // Dial takes less than maxElapsed or
+ // the test times out.
+ for {
+ startTime := time.Now()
+ conn2, err := Dial(network, addr)
+ if err == nil {
+ conn2.Close()
+ t.Fatal("error expected")
+ }
+ elapsed := time.Since(startTime)
+ if elapsed < maxElapsed {
+ break
+ }
+ t.Logf("got %v; want < %v", elapsed, maxElapsed)
+ }
+ })
+ }
+}
+
+// Issue 18806: it should always be possible to net.Dial a
+// net.Listener().Addr().String when the listen address was ":n", even
+// if the machine has halfway configured IPv6 such that it can bind on
+// "::" not connect back to that same address.
+func TestDialListenerAddr(t *testing.T) {
+ if !testableNetwork("tcp4") {
+ t.Skipf("skipping: can't listen on tcp4")
+ }
+
+ // The original issue report was for listening on just ":0" on a system that
+ // supports both tcp4 and tcp6 for external traffic but only tcp4 for loopback
+ // traffic. However, the port opened by ":0" is externally-accessible, and may
+ // trigger firewall alerts or otherwise be mistaken for malicious activity
+ // (see https://go.dev/issue/59497). Moreover, it often does not reproduce
+ // the scenario in the issue, in which the port *cannot* be dialed as tcp6.
+ //
+ // To address both of those problems, we open a tcp4-only localhost port, but
+ // then dial the address string that the listener would have reported for a
+ // dual-stack port.
+ ln, err := Listen("tcp4", "localhost:0")
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer ln.Close()
+
+ t.Logf("listening on %q", ln.Addr())
+ _, port, err := SplitHostPort(ln.Addr().String())
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ // If we had opened a dual-stack port without an explicit "localhost" address,
+ // the Listener would arbitrarily report an empty tcp6 address in its Addr
+ // string.
+ //
+ // The documentation for Dial says ‘if the host is empty or a literal
+ // unspecified IP address, as in ":80", "0.0.0.0:80" or "[::]:80" for TCP and
+ // UDP, "", "0.0.0.0" or "::" for IP, the local system is assumed.’
+ // In #18806, it was decided that that should include the local tcp4 host
+ // even if the string is in the tcp6 format.
+ dialAddr := "[::]:" + port
+ c, err := Dial("tcp4", dialAddr)
+ if err != nil {
+ t.Fatalf(`Dial("tcp4", %q): %v`, dialAddr, err)
+ }
+ c.Close()
+ t.Logf(`Dial("tcp4", %q) succeeded`, dialAddr)
+}
+
+func TestDialerControl(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ case "js", "wasip1":
+ t.Skipf("skipping: fake net does not support Dialer.Control")
+ }
+
+ t.Run("StreamDial", func(t *testing.T) {
+ for _, network := range []string{"tcp", "tcp4", "tcp6", "unix", "unixpacket"} {
+ if !testableNetwork(network) {
+ continue
+ }
+ ln := newLocalListener(t, network)
+ defer ln.Close()
+ d := Dialer{Control: controlOnConnSetup}
+ c, err := d.Dial(network, ln.Addr().String())
+ if err != nil {
+ t.Error(err)
+ continue
+ }
+ c.Close()
+ }
+ })
+ t.Run("PacketDial", func(t *testing.T) {
+ for _, network := range []string{"udp", "udp4", "udp6", "unixgram"} {
+ if !testableNetwork(network) {
+ continue
+ }
+ c1 := newLocalPacketListener(t, network)
+ if network == "unixgram" {
+ defer os.Remove(c1.LocalAddr().String())
+ }
+ defer c1.Close()
+ d := Dialer{Control: controlOnConnSetup}
+ c2, err := d.Dial(network, c1.LocalAddr().String())
+ if err != nil {
+ t.Error(err)
+ continue
+ }
+ c2.Close()
+ }
+ })
+}
+
+func TestDialerControlContext(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9":
+ t.Skipf("%s does not have full support of socktest", runtime.GOOS)
+ case "js", "wasip1":
+ t.Skipf("skipping: fake net does not support Dialer.ControlContext")
+ }
+ t.Run("StreamDial", func(t *testing.T) {
+ for i, network := range []string{"tcp", "tcp4", "tcp6", "unix", "unixpacket"} {
+ t.Run(network, func(t *testing.T) {
+ if !testableNetwork(network) {
+ t.Skipf("skipping: %s not available", network)
+ }
+
+ ln := newLocalListener(t, network)
+ defer ln.Close()
+ var id int
+ d := Dialer{ControlContext: func(ctx context.Context, network string, address string, c syscall.RawConn) error {
+ id = ctx.Value("id").(int)
+ return controlOnConnSetup(network, address, c)
+ }}
+ c, err := d.DialContext(context.WithValue(context.Background(), "id", i+1), network, ln.Addr().String())
+ if err != nil {
+ t.Fatal(err)
+ }
+ if id != i+1 {
+ t.Errorf("got id %d, want %d", id, i+1)
+ }
+ c.Close()
+ })
+ }
+ })
+}
+
+func TestDialContext(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ case "js", "wasip1":
+ t.Skipf("skipping: fake net does not support Dialer.ControlContext")
+ }
+
+ t.Run("StreamDial", func(t *testing.T) {
+ var err error
+ for i, network := range []string{"tcp", "tcp4", "tcp6", "unix", "unixpacket"} {
+ if !testableNetwork(network) {
+ continue
+ }
+ ln := newLocalListener(t, network)
+ defer ln.Close()
+ var id int
+ d := Dialer{ControlContext: func(ctx context.Context, network string, address string, c syscall.RawConn) error {
+ id = ctx.Value("id").(int)
+ return controlOnConnSetup(network, address, c)
+ }}
+ var c Conn
+ switch network {
+ case "tcp", "tcp4", "tcp6":
+ raddr, err := netip.ParseAddrPort(ln.Addr().String())
+ if err != nil {
+ t.Error(err)
+ continue
+ }
+ c, err = d.DialTCP(context.WithValue(context.Background(), "id", i+1), network, (*TCPAddr)(nil).AddrPort(), raddr)
+ case "unix", "unixpacket":
+ raddr, err := ResolveUnixAddr(network, ln.Addr().String())
+ if err != nil {
+ t.Error(err)
+ continue
+ }
+ c, err = d.DialUnix(context.WithValue(context.Background(), "id", i+1), network, nil, raddr)
+ }
+ if err != nil {
+ t.Error(err)
+ continue
+ }
+ if id != i+1 {
+ t.Errorf("%s: got id %d, want %d", network, id, i+1)
+ }
+ c.Close()
+ }
+ })
+ t.Run("PacketDial", func(t *testing.T) {
+ var err error
+ for i, network := range []string{"udp", "udp4", "udp6", "unixgram"} {
+ if !testableNetwork(network) {
+ continue
+ }
+ c1 := newLocalPacketListener(t, network)
+ if network == "unixgram" {
+ defer os.Remove(c1.LocalAddr().String())
+ }
+ defer c1.Close()
+ var id int
+ d := Dialer{ControlContext: func(ctx context.Context, network string, address string, c syscall.RawConn) error {
+ id = ctx.Value("id").(int)
+ return controlOnConnSetup(network, address, c)
+ }}
+ var c2 Conn
+ switch network {
+ case "udp", "udp4", "udp6":
+ raddr, err := netip.ParseAddrPort(c1.LocalAddr().String())
+ if err != nil {
+ t.Error(err)
+ continue
+ }
+ c2, err = d.DialUDP(context.WithValue(context.Background(), "id", i+1), network, (*UDPAddr)(nil).AddrPort(), raddr)
+ case "unixgram":
+ raddr, err := ResolveUnixAddr(network, c1.LocalAddr().String())
+ if err != nil {
+ t.Error(err)
+ continue
+ }
+ c2, err = d.DialUnix(context.WithValue(context.Background(), "id", i+1), network, nil, raddr)
+ }
+ if err != nil {
+ t.Error(err)
+ continue
+ }
+ if id != i+1 {
+ t.Errorf("%s: got id %d, want %d", network, id, i+1)
+ }
+ c2.Close()
+ }
+ })
+}
+
+// mustHaveExternalNetwork is like testenv.MustHaveExternalNetwork
+// except on non-Linux, non-mobile builders it permits the test to
+// run in -short mode.
+func mustHaveExternalNetwork(t *testing.T) {
+ t.Helper()
+ definitelyHasLongtestBuilder := runtime.GOOS == "linux"
+ mobile := runtime.GOOS == "android" || runtime.GOOS == "ios"
+ fake := runtime.GOOS == "js" || runtime.GOOS == "wasip1"
+ if testenv.Builder() != "" && !definitelyHasLongtestBuilder && !mobile && !fake {
+ // On a non-Linux, non-mobile builder (e.g., freebsd-amd64-13_0).
+ //
+ // Don't skip testing because otherwise the test may never run on
+ // any builder if this port doesn't also have a -longtest builder.
+ return
+ }
+ testenv.MustHaveExternalNetwork(t)
+}
+
+type contextWithNonZeroDeadline struct {
+ context.Context
+}
+
+func (contextWithNonZeroDeadline) Deadline() (time.Time, bool) {
+ // Return non-zero time.Time value with false indicating that no deadline is set.
+ return time.Unix(0, 0), false
+}
+
+func TestDialWithNonZeroDeadline(t *testing.T) {
+ ln := newLocalListener(t, "tcp")
+ defer ln.Close()
+ _, port, err := SplitHostPort(ln.Addr().String())
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ ctx := contextWithNonZeroDeadline{Context: context.Background()}
+ var dialer Dialer
+ c, err := dialer.DialContext(ctx, "tcp", JoinHostPort("", port))
+ if err != nil {
+ t.Fatal(err)
+ }
+ c.Close()
+}
diff --git a/go/src/net/dial_unix_test.go b/go/src/net/dial_unix_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..d0df0b71eaeea5fb6b624897140c25f20bbc4884
--- /dev/null
+++ b/go/src/net/dial_unix_test.go
@@ -0,0 +1,113 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+package net
+
+import (
+ "context"
+ "errors"
+ "syscall"
+ "testing"
+ "time"
+)
+
+func init() {
+ isEADDRINUSE = func(err error) bool {
+ return errors.Is(err, syscall.EADDRINUSE)
+ }
+}
+
+// Issue 16523
+func TestDialContextCancelRace(t *testing.T) {
+ oldConnectFunc := connectFunc
+ oldGetsockoptIntFunc := getsockoptIntFunc
+ oldTestHookCanceledDial := testHookCanceledDial
+ defer func() {
+ connectFunc = oldConnectFunc
+ getsockoptIntFunc = oldGetsockoptIntFunc
+ testHookCanceledDial = oldTestHookCanceledDial
+ }()
+
+ ln := newLocalListener(t, "tcp")
+ listenerDone := make(chan struct{})
+ go func() {
+ defer close(listenerDone)
+ c, err := ln.Accept()
+ if err == nil {
+ c.Close()
+ }
+ }()
+ defer func() { <-listenerDone }()
+ defer ln.Close()
+
+ sawCancel := make(chan bool, 1)
+ testHookCanceledDial = func() {
+ sawCancel <- true
+ }
+
+ ctx, cancelCtx := context.WithCancel(context.Background())
+
+ connectFunc = func(fd int, addr syscall.Sockaddr) error {
+ err := oldConnectFunc(fd, addr)
+ t.Logf("connect(%d, addr) = %v", fd, err)
+ if err == nil {
+ // On some operating systems, localhost
+ // connects _sometimes_ succeed immediately.
+ // Prevent that, so we exercise the code path
+ // we're interested in testing. This seems
+ // harmless. It makes FreeBSD 10.10 work when
+ // run with many iterations. It failed about
+ // half the time previously.
+ return syscall.EINPROGRESS
+ }
+ return err
+ }
+
+ getsockoptIntFunc = func(fd, level, opt int) (val int, err error) {
+ val, err = oldGetsockoptIntFunc(fd, level, opt)
+ t.Logf("getsockoptIntFunc(%d, %d, %d) = (%v, %v)", fd, level, opt, val, err)
+ if level == syscall.SOL_SOCKET && opt == syscall.SO_ERROR && err == nil && val == 0 {
+ t.Logf("canceling context")
+
+ // Cancel the context at just the moment which
+ // caused the race in issue 16523.
+ cancelCtx()
+
+ // And wait for the "interrupter" goroutine to
+ // cancel the dial by messing with its write
+ // timeout before returning.
+ select {
+ case <-sawCancel:
+ t.Logf("saw cancel")
+ case <-time.After(5 * time.Second):
+ t.Errorf("didn't see cancel after 5 seconds")
+ }
+ }
+ return
+ }
+
+ var d Dialer
+ c, err := d.DialContext(ctx, "tcp", ln.Addr().String())
+ if err == nil {
+ c.Close()
+ t.Fatal("unexpected successful dial; want context canceled error")
+ }
+
+ select {
+ case <-ctx.Done():
+ case <-time.After(5 * time.Second):
+ t.Fatal("expected context to be canceled")
+ }
+
+ oe, ok := err.(*OpError)
+ if !ok || oe.Op != "dial" {
+ t.Fatalf("Dial error = %#v; want dial *OpError", err)
+ }
+
+ if oe.Err != errCanceled {
+ t.Errorf("DialContext = (%v, %v); want OpError with error %v", c, err, errCanceled)
+ }
+}
diff --git a/go/src/net/dnsclient.go b/go/src/net/dnsclient.go
new file mode 100644
index 0000000000000000000000000000000000000000..eb509d175fc1a0a53a0c68162802d688bb25b5ab
--- /dev/null
+++ b/go/src/net/dnsclient.go
@@ -0,0 +1,239 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "cmp"
+ "internal/bytealg"
+ "internal/strconv"
+ "slices"
+ _ "unsafe" // for go:linkname
+
+ "golang.org/x/net/dns/dnsmessage"
+)
+
+// provided by runtime
+//
+//go:linkname runtime_rand runtime.rand
+func runtime_rand() uint64
+
+func randInt() int {
+ return int(uint(runtime_rand()) >> 1) // clear sign bit
+}
+
+func randIntn(n int) int {
+ return randInt() % n
+}
+
+// reverseaddr returns the in-addr.arpa. or ip6.arpa. hostname of the IP
+// address addr suitable for rDNS (PTR) record lookup or an error if it fails
+// to parse the IP address.
+func reverseaddr(addr string) (arpa string, err error) {
+ ip := ParseIP(addr)
+ if ip == nil {
+ return "", &DNSError{Err: "unrecognized address", Name: addr}
+ }
+ if ip.To4() != nil {
+ return strconv.Itoa(int(ip[15])) + "." + strconv.Itoa(int(ip[14])) + "." + strconv.Itoa(int(ip[13])) + "." + strconv.Itoa(int(ip[12])) + ".in-addr.arpa.", nil
+ }
+ // Must be IPv6
+ buf := make([]byte, 0, len(ip)*4+len("ip6.arpa."))
+ // Add it, in reverse, to the buffer
+ for i := len(ip) - 1; i >= 0; i-- {
+ v := ip[i]
+ buf = append(buf, hexDigit[v&0xF],
+ '.',
+ hexDigit[v>>4],
+ '.')
+ }
+ // Append "ip6.arpa." and return (buf already has the final .)
+ buf = append(buf, "ip6.arpa."...)
+ return string(buf), nil
+}
+
+func equalASCIIName(x, y dnsmessage.Name) bool {
+ if x.Length != y.Length {
+ return false
+ }
+ for i := 0; i < int(x.Length); i++ {
+ a := x.Data[i]
+ b := y.Data[i]
+ if 'A' <= a && a <= 'Z' {
+ a += 0x20
+ }
+ if 'A' <= b && b <= 'Z' {
+ b += 0x20
+ }
+ if a != b {
+ return false
+ }
+ }
+ return true
+}
+
+// isDomainName checks if a string is a presentation-format domain name
+// (currently restricted to hostname-compatible "preferred name" LDH labels and
+// SRV-like "underscore labels"; see golang.org/issue/12421).
+//
+// isDomainName should be an internal detail,
+// but widely used packages access it using linkname.
+// Notable members of the hall of shame include:
+// - github.com/sagernet/sing
+//
+// Do not remove or change the type signature.
+// See go.dev/issue/67401.
+//
+//go:linkname isDomainName
+func isDomainName(s string) bool {
+ // The root domain name is valid. See golang.org/issue/45715.
+ if s == "." {
+ return true
+ }
+
+ // See RFC 1035, RFC 3696.
+ // Presentation format has dots before every label except the first, and the
+ // terminal empty label is optional here because we assume fully-qualified
+ // (absolute) input. We must therefore reserve space for the first and last
+ // labels' length octets in wire format, where they are necessary and the
+ // maximum total length is 255.
+ // So our _effective_ maximum is 253, but 254 is not rejected if the last
+ // character is a dot.
+ l := len(s)
+ if l == 0 || l > 254 || l == 254 && s[l-1] != '.' {
+ return false
+ }
+
+ last := byte('.')
+ nonNumeric := false // true once we've seen a letter or hyphen
+ partlen := 0
+ for i := 0; i < len(s); i++ {
+ c := s[i]
+ switch {
+ default:
+ return false
+ case 'a' <= c && c <= 'z' || 'A' <= c && c <= 'Z' || c == '_':
+ nonNumeric = true
+ partlen++
+ case '0' <= c && c <= '9':
+ // fine
+ partlen++
+ case c == '-':
+ // Byte before dash cannot be dot.
+ if last == '.' {
+ return false
+ }
+ partlen++
+ nonNumeric = true
+ case c == '.':
+ // Byte before dot cannot be dot, dash.
+ if last == '.' || last == '-' {
+ return false
+ }
+ if partlen > 63 || partlen == 0 {
+ return false
+ }
+ partlen = 0
+ }
+ last = c
+ }
+ if last == '-' || partlen > 63 {
+ return false
+ }
+
+ return nonNumeric
+}
+
+// absDomainName returns an absolute domain name which ends with a
+// trailing dot to match pure Go reverse resolver and all other lookup
+// routines.
+// See golang.org/issue/12189.
+// But we don't want to add dots for local names from /etc/hosts.
+// It's hard to tell so we settle on the heuristic that names without dots
+// (like "localhost" or "myhost") do not get trailing dots, but any other
+// names do.
+func absDomainName(s string) string {
+ if bytealg.IndexByteString(s, '.') != -1 && s[len(s)-1] != '.' {
+ s += "."
+ }
+ return s
+}
+
+// An SRV represents a single DNS SRV record.
+type SRV struct {
+ Target string
+ Port uint16
+ Priority uint16
+ Weight uint16
+}
+
+// byPriorityWeight sorts SRV records by ascending priority and weight.
+type byPriorityWeight []*SRV
+
+// shuffleByWeight shuffles SRV records by weight using the algorithm
+// described in RFC 2782.
+func (addrs byPriorityWeight) shuffleByWeight() {
+ sum := 0
+ for _, addr := range addrs {
+ sum += int(addr.Weight)
+ }
+ for sum > 0 && len(addrs) > 1 {
+ s := 0
+ n := randIntn(sum)
+ for i := range addrs {
+ s += int(addrs[i].Weight)
+ if s > n {
+ if i > 0 {
+ addrs[0], addrs[i] = addrs[i], addrs[0]
+ }
+ break
+ }
+ }
+ sum -= int(addrs[0].Weight)
+ addrs = addrs[1:]
+ }
+}
+
+// sort reorders SRV records as specified in RFC 2782.
+func (addrs byPriorityWeight) sort() {
+ slices.SortFunc(addrs, func(a, b *SRV) int {
+ if r := cmp.Compare(a.Priority, b.Priority); r != 0 {
+ return r
+ }
+ return cmp.Compare(a.Weight, b.Weight)
+ })
+ i := 0
+ for j := 1; j < len(addrs); j++ {
+ if addrs[i].Priority != addrs[j].Priority {
+ addrs[i:j].shuffleByWeight()
+ i = j
+ }
+ }
+ addrs[i:].shuffleByWeight()
+}
+
+// An MX represents a single DNS MX record.
+type MX struct {
+ Host string
+ Pref uint16
+}
+
+// byPref sorts MX records by preference
+type byPref []*MX
+
+// sort reorders MX records as specified in RFC 5321.
+func (s byPref) sort() {
+ for i := range s {
+ j := randIntn(i + 1)
+ s[i], s[j] = s[j], s[i]
+ }
+ slices.SortFunc(s, func(a, b *MX) int {
+ return cmp.Compare(a.Pref, b.Pref)
+ })
+}
+
+// An NS represents a single DNS NS record.
+type NS struct {
+ Host string
+}
diff --git a/go/src/net/dnsclient_test.go b/go/src/net/dnsclient_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..24cd69e13be25d932760cdd4e195c46625dd004f
--- /dev/null
+++ b/go/src/net/dnsclient_test.go
@@ -0,0 +1,66 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "testing"
+)
+
+func checkDistribution(t *testing.T, data []*SRV, margin float64) {
+ sum := 0
+ for _, srv := range data {
+ sum += int(srv.Weight)
+ }
+
+ results := make(map[string]int)
+
+ count := 10000
+ for j := 0; j < count; j++ {
+ d := make([]*SRV, len(data))
+ copy(d, data)
+ byPriorityWeight(d).shuffleByWeight()
+ key := d[0].Target
+ results[key] = results[key] + 1
+ }
+
+ actual := results[data[0].Target]
+ expected := float64(count) * float64(data[0].Weight) / float64(sum)
+ diff := float64(actual) - expected
+ t.Logf("actual: %v diff: %v e: %v m: %v", actual, diff, expected, margin)
+ if diff < 0 {
+ diff = -diff
+ }
+ if diff > (expected * margin) {
+ t.Errorf("missed target weight: expected %v, %v", expected, actual)
+ }
+}
+
+func testUniformity(t *testing.T, size int, margin float64) {
+ data := make([]*SRV, size)
+ for i := 0; i < size; i++ {
+ data[i] = &SRV{Target: string('a' + rune(i)), Weight: 1}
+ }
+ checkDistribution(t, data, margin)
+}
+
+func TestDNSSRVUniformity(t *testing.T) {
+ testUniformity(t, 2, 0.05)
+ testUniformity(t, 3, 0.10)
+ testUniformity(t, 10, 0.20)
+ testWeighting(t, 0.05)
+}
+
+func testWeighting(t *testing.T, margin float64) {
+ data := []*SRV{
+ {Target: "a", Weight: 60},
+ {Target: "b", Weight: 30},
+ {Target: "c", Weight: 10},
+ }
+ checkDistribution(t, data, margin)
+}
+
+func TestWeighting(t *testing.T) {
+ testWeighting(t, 0.05)
+}
diff --git a/go/src/net/dnsclient_unix.go b/go/src/net/dnsclient_unix.go
new file mode 100644
index 0000000000000000000000000000000000000000..40f76062944f465fc05e7c2d690477565a261e5c
--- /dev/null
+++ b/go/src/net/dnsclient_unix.go
@@ -0,0 +1,892 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// DNS client: see RFC 1035.
+// Has to be linked into package net for Dial.
+
+// TODO(rsc):
+// Could potentially handle many outstanding lookups faster.
+// Random UDP source port (net.Dial should do that for us).
+// Random request IDs.
+
+package net
+
+import (
+ "context"
+ "errors"
+ "internal/bytealg"
+ "internal/godebug"
+ "internal/strconv"
+ "internal/stringslite"
+ "io"
+ "os"
+ "runtime"
+ "sync"
+ "sync/atomic"
+ "time"
+
+ "golang.org/x/net/dns/dnsmessage"
+)
+
+const (
+ // to be used as a useTCP parameter to exchange
+ useTCPOnly = true
+ useUDPOrTCP = false
+
+ // Maximum DNS packet size.
+ // Value taken from https://dnsflagday.net/2020/.
+ maxDNSPacketSize = 1232
+)
+
+var (
+ errLameReferral = errors.New("lame referral")
+ errCannotUnmarshalDNSMessage = errors.New("cannot unmarshal DNS message")
+ errCannotMarshalDNSMessage = errors.New("cannot marshal DNS message")
+ errServerMisbehaving = errors.New("server misbehaving")
+ errInvalidDNSResponse = errors.New("invalid DNS response")
+ errNoAnswerFromDNSServer = errors.New("no answer from DNS server")
+
+ // errServerTemporarilyMisbehaving is like errServerMisbehaving, except
+ // that when it gets translated to a DNSError, the IsTemporary field
+ // gets set to true.
+ errServerTemporarilyMisbehaving = &temporaryError{"server misbehaving"}
+)
+
+// netedns0 controls whether we send an EDNS0 additional header.
+var netedns0 = godebug.New("netedns0")
+
+func newRequest(q dnsmessage.Question, ad bool) (id uint16, udpReq, tcpReq []byte, err error) {
+ id = uint16(randInt())
+ b := dnsmessage.NewBuilder(make([]byte, 2, 514), dnsmessage.Header{ID: id, RecursionDesired: true, AuthenticData: ad})
+ if err := b.StartQuestions(); err != nil {
+ return 0, nil, nil, err
+ }
+ if err := b.Question(q); err != nil {
+ return 0, nil, nil, err
+ }
+
+ if netedns0.Value() == "0" {
+ netedns0.IncNonDefault()
+ } else {
+ // Accept packets up to maxDNSPacketSize. RFC 6891.
+ if err := b.StartAdditionals(); err != nil {
+ return 0, nil, nil, err
+ }
+ var rh dnsmessage.ResourceHeader
+ if err := rh.SetEDNS0(maxDNSPacketSize, dnsmessage.RCodeSuccess, false); err != nil {
+ return 0, nil, nil, err
+ }
+ if err := b.OPTResource(rh, dnsmessage.OPTResource{}); err != nil {
+ return 0, nil, nil, err
+ }
+ }
+
+ tcpReq, err = b.Finish()
+ if err != nil {
+ return 0, nil, nil, err
+ }
+ udpReq = tcpReq[2:]
+ l := len(tcpReq) - 2
+ tcpReq[0] = byte(l >> 8)
+ tcpReq[1] = byte(l)
+ return id, udpReq, tcpReq, nil
+}
+
+func checkResponse(reqID uint16, reqQues dnsmessage.Question, respHdr dnsmessage.Header, respQues dnsmessage.Question) bool {
+ if !respHdr.Response {
+ return false
+ }
+ if reqID != respHdr.ID {
+ return false
+ }
+ if reqQues.Type != respQues.Type || reqQues.Class != respQues.Class || !equalASCIIName(reqQues.Name, respQues.Name) {
+ return false
+ }
+ return true
+}
+
+func dnsPacketRoundTrip(c Conn, id uint16, query dnsmessage.Question, b []byte) (dnsmessage.Parser, dnsmessage.Header, error) {
+ if _, err := c.Write(b); err != nil {
+ return dnsmessage.Parser{}, dnsmessage.Header{}, err
+ }
+
+ b = make([]byte, maxDNSPacketSize)
+ for {
+ n, err := c.Read(b)
+ if err != nil {
+ return dnsmessage.Parser{}, dnsmessage.Header{}, err
+ }
+ var p dnsmessage.Parser
+ // Ignore invalid responses as they may be malicious
+ // forgery attempts. Instead continue waiting until
+ // timeout. See golang.org/issue/13281.
+ h, err := p.Start(b[:n])
+ if err != nil {
+ continue
+ }
+ q, err := p.Question()
+ if err != nil || !checkResponse(id, query, h, q) {
+ continue
+ }
+ return p, h, nil
+ }
+}
+
+func dnsStreamRoundTrip(c Conn, id uint16, query dnsmessage.Question, b []byte) (dnsmessage.Parser, dnsmessage.Header, error) {
+ if _, err := c.Write(b); err != nil {
+ return dnsmessage.Parser{}, dnsmessage.Header{}, err
+ }
+
+ b = make([]byte, 1280) // 1280 is a reasonable initial size for IP over Ethernet, see RFC 4035
+ if _, err := io.ReadFull(c, b[:2]); err != nil {
+ return dnsmessage.Parser{}, dnsmessage.Header{}, err
+ }
+ l := int(b[0])<<8 | int(b[1])
+ if l > len(b) {
+ b = make([]byte, l)
+ }
+ n, err := io.ReadFull(c, b[:l])
+ if err != nil {
+ return dnsmessage.Parser{}, dnsmessage.Header{}, err
+ }
+ var p dnsmessage.Parser
+ h, err := p.Start(b[:n])
+ if err != nil {
+ return dnsmessage.Parser{}, dnsmessage.Header{}, errCannotUnmarshalDNSMessage
+ }
+ q, err := p.Question()
+ if err != nil {
+ return dnsmessage.Parser{}, dnsmessage.Header{}, errCannotUnmarshalDNSMessage
+ }
+ if !checkResponse(id, query, h, q) {
+ return dnsmessage.Parser{}, dnsmessage.Header{}, errInvalidDNSResponse
+ }
+ return p, h, nil
+}
+
+// exchange sends a query on the connection and hopes for a response.
+func (r *Resolver) exchange(ctx context.Context, server string, q dnsmessage.Question, timeout time.Duration, useTCP, ad bool) (dnsmessage.Parser, dnsmessage.Header, error) {
+ q.Class = dnsmessage.ClassINET
+ id, udpReq, tcpReq, err := newRequest(q, ad)
+ if err != nil {
+ return dnsmessage.Parser{}, dnsmessage.Header{}, errCannotMarshalDNSMessage
+ }
+ var networks []string
+ if useTCP {
+ networks = []string{"tcp"}
+ } else {
+ networks = []string{"udp", "tcp"}
+ }
+ for _, network := range networks {
+ ctx, cancel := context.WithDeadline(ctx, time.Now().Add(timeout))
+ defer cancel()
+
+ c, err := r.dial(ctx, network, server)
+ if err != nil {
+ return dnsmessage.Parser{}, dnsmessage.Header{}, err
+ }
+ if d, ok := ctx.Deadline(); ok && !d.IsZero() {
+ c.SetDeadline(d)
+ }
+ var p dnsmessage.Parser
+ var h dnsmessage.Header
+ if _, ok := c.(PacketConn); ok {
+ p, h, err = dnsPacketRoundTrip(c, id, q, udpReq)
+ } else {
+ p, h, err = dnsStreamRoundTrip(c, id, q, tcpReq)
+ }
+ c.Close()
+ if err != nil {
+ return dnsmessage.Parser{}, dnsmessage.Header{}, mapErr(err)
+ }
+ if err := p.SkipQuestion(); err != dnsmessage.ErrSectionDone {
+ return dnsmessage.Parser{}, dnsmessage.Header{}, errInvalidDNSResponse
+ }
+ // RFC 5966 indicates that when a client receives a UDP response with
+ // the TC flag set, it should take the TC flag as an indication that it
+ // should retry over TCP instead.
+ // The case when the TC flag is set in a TCP response is not well specified,
+ // so this implements the glibc resolver behavior, returning the existing
+ // dns response instead of returning a "errNoAnswerFromDNSServer" error.
+ // See go.dev/issue/64896
+ if h.Truncated && network == "udp" {
+ continue
+ }
+ return p, h, nil
+ }
+ return dnsmessage.Parser{}, dnsmessage.Header{}, errNoAnswerFromDNSServer
+}
+
+// checkHeader performs basic sanity checks on the header.
+func checkHeader(p *dnsmessage.Parser, h dnsmessage.Header) error {
+ rcode, hasAdd := extractExtendedRCode(*p, h)
+
+ if rcode == dnsmessage.RCodeNameError {
+ return errNoSuchHost
+ }
+
+ _, err := p.AnswerHeader()
+ if err != nil && err != dnsmessage.ErrSectionDone {
+ return errCannotUnmarshalDNSMessage
+ }
+
+ // libresolv continues to the next server when it receives
+ // an invalid referral response. See golang.org/issue/15434.
+ if rcode == dnsmessage.RCodeSuccess && !h.Authoritative && !h.RecursionAvailable && err == dnsmessage.ErrSectionDone && !hasAdd {
+ return errLameReferral
+ }
+
+ if rcode != dnsmessage.RCodeSuccess && rcode != dnsmessage.RCodeNameError {
+ // None of the error codes make sense
+ // for the query we sent. If we didn't get
+ // a name error and we didn't get success,
+ // the server is behaving incorrectly or
+ // having temporary trouble.
+ if rcode == dnsmessage.RCodeServerFailure {
+ return errServerTemporarilyMisbehaving
+ }
+ return errServerMisbehaving
+ }
+
+ return nil
+}
+
+func skipToAnswer(p *dnsmessage.Parser, qtype dnsmessage.Type) error {
+ for {
+ h, err := p.AnswerHeader()
+ if err == dnsmessage.ErrSectionDone {
+ return errNoSuchHost
+ }
+ if err != nil {
+ return errCannotUnmarshalDNSMessage
+ }
+ if h.Type == qtype {
+ return nil
+ }
+ if err := p.SkipAnswer(); err != nil {
+ return errCannotUnmarshalDNSMessage
+ }
+ }
+}
+
+// extractExtendedRCode extracts the extended RCode from the OPT resource (EDNS(0))
+// If an OPT record is not found, the RCode from the hdr is returned.
+// Another return value indicates whether an additional resource was found.
+func extractExtendedRCode(p dnsmessage.Parser, hdr dnsmessage.Header) (dnsmessage.RCode, bool) {
+ p.SkipAllAnswers()
+ p.SkipAllAuthorities()
+ hasAdd := false
+ for {
+ ahdr, err := p.AdditionalHeader()
+ if err != nil {
+ return hdr.RCode, hasAdd
+ }
+ hasAdd = true
+ if ahdr.Type == dnsmessage.TypeOPT {
+ return ahdr.ExtendedRCode(hdr.RCode), hasAdd
+ }
+ if err := p.SkipAdditional(); err != nil {
+ return hdr.RCode, hasAdd
+ }
+ }
+}
+
+// Do a lookup for a single name, which must be rooted
+// (otherwise answer will not find the answers).
+func (r *Resolver) tryOneName(ctx context.Context, cfg *dnsConfig, name string, qtype dnsmessage.Type) (dnsmessage.Parser, string, error) {
+ var lastErr error
+ serverOffset := cfg.serverOffset()
+ sLen := uint32(len(cfg.servers))
+
+ n, err := dnsmessage.NewName(name)
+ if err != nil {
+ return dnsmessage.Parser{}, "", &DNSError{Err: errCannotMarshalDNSMessage.Error(), Name: name}
+ }
+ q := dnsmessage.Question{
+ Name: n,
+ Type: qtype,
+ Class: dnsmessage.ClassINET,
+ }
+
+ for i := 0; i < cfg.attempts; i++ {
+ for j := uint32(0); j < sLen; j++ {
+ server := cfg.servers[(serverOffset+j)%sLen]
+
+ p, h, err := r.exchange(ctx, server, q, cfg.timeout, cfg.useTCP, cfg.trustAD)
+ if err != nil {
+ dnsErr := newDNSError(err, name, server)
+ // Set IsTemporary for socket-level errors. Note that this flag
+ // may also be used to indicate a SERVFAIL response.
+ if _, ok := err.(*OpError); ok {
+ dnsErr.IsTemporary = true
+ }
+ lastErr = dnsErr
+ continue
+ }
+
+ if err := checkHeader(&p, h); err != nil {
+ if err == errNoSuchHost {
+ // The name does not exist, so trying
+ // another server won't help.
+ return p, server, newDNSError(errNoSuchHost, name, server)
+ }
+ lastErr = newDNSError(err, name, server)
+ continue
+ }
+
+ if err := skipToAnswer(&p, qtype); err != nil {
+ if err == errNoSuchHost {
+ // The name does not exist, so trying
+ // another server won't help.
+ return p, server, newDNSError(errNoSuchHost, name, server)
+ }
+ lastErr = newDNSError(err, name, server)
+ continue
+ }
+
+ return p, server, nil
+ }
+ }
+ return dnsmessage.Parser{}, "", lastErr
+}
+
+// A resolverConfig represents a DNS stub resolver configuration.
+type resolverConfig struct {
+ initOnce sync.Once // guards init of resolverConfig
+
+ // ch is used as a semaphore that only allows one lookup at a
+ // time to recheck resolv.conf.
+ ch chan struct{} // guards lastChecked and modTime
+ lastChecked time.Time // last time resolv.conf was checked
+
+ dnsConfig atomic.Pointer[dnsConfig] // parsed resolv.conf structure used in lookups
+}
+
+var resolvConf resolverConfig
+
+func getSystemDNSConfig() *dnsConfig {
+ resolvConf.tryUpdate("/etc/resolv.conf")
+ return resolvConf.dnsConfig.Load()
+}
+
+// init initializes conf and is only called via conf.initOnce.
+func (conf *resolverConfig) init() {
+ // Set dnsConfig and lastChecked so we don't parse
+ // resolv.conf twice the first time.
+ conf.dnsConfig.Store(dnsReadConfig("/etc/resolv.conf"))
+ conf.lastChecked = time.Now()
+
+ // Prepare ch so that only one update of resolverConfig may
+ // run at once.
+ conf.ch = make(chan struct{}, 1)
+}
+
+// tryUpdate tries to update conf with the named resolv.conf file.
+// The name variable only exists for testing. It is otherwise always
+// "/etc/resolv.conf".
+func (conf *resolverConfig) tryUpdate(name string) {
+ conf.initOnce.Do(conf.init)
+
+ if conf.dnsConfig.Load().noReload {
+ return
+ }
+
+ // Ensure only one update at a time checks resolv.conf.
+ if !conf.tryAcquireSema() {
+ return
+ }
+ defer conf.releaseSema()
+
+ now := time.Now()
+ if conf.lastChecked.After(now.Add(-5 * time.Second)) {
+ return
+ }
+ conf.lastChecked = now
+
+ switch runtime.GOOS {
+ case "windows":
+ // There's no file on disk, so don't bother checking
+ // and failing.
+ //
+ // The Windows implementation of dnsReadConfig (called
+ // below) ignores the name.
+ default:
+ var mtime time.Time
+ if fi, err := os.Stat(name); err == nil {
+ mtime = fi.ModTime()
+ }
+ if mtime.Equal(conf.dnsConfig.Load().mtime) {
+ return
+ }
+ }
+
+ dnsConf := dnsReadConfig(name)
+ conf.dnsConfig.Store(dnsConf)
+}
+
+func (conf *resolverConfig) tryAcquireSema() bool {
+ select {
+ case conf.ch <- struct{}{}:
+ return true
+ default:
+ return false
+ }
+}
+
+func (conf *resolverConfig) releaseSema() {
+ <-conf.ch
+}
+
+func (r *Resolver) lookup(ctx context.Context, name string, qtype dnsmessage.Type, conf *dnsConfig) (dnsmessage.Parser, string, error) {
+ if !isDomainName(name) {
+ // We used to use "invalid domain name" as the error,
+ // but that is a detail of the specific lookup mechanism.
+ // Other lookups might allow broader name syntax
+ // (for example Multicast DNS allows UTF-8; see RFC 6762).
+ // For consistency with libc resolvers, report no such host.
+ return dnsmessage.Parser{}, "", newDNSError(errNoSuchHost, name, "")
+ }
+
+ if conf == nil {
+ conf = getSystemDNSConfig()
+ }
+
+ var (
+ p dnsmessage.Parser
+ server string
+ err error
+ )
+ for _, fqdn := range conf.nameList(name) {
+ p, server, err = r.tryOneName(ctx, conf, fqdn, qtype)
+ if err == nil {
+ break
+ }
+ if nerr, ok := err.(Error); ok && nerr.Temporary() && r.strictErrors() {
+ // If we hit a temporary error with StrictErrors enabled,
+ // stop immediately instead of trying more names.
+ break
+ }
+ }
+ if err == nil {
+ return p, server, nil
+ }
+ if err, ok := err.(*DNSError); ok {
+ // Show original name passed to lookup, not suffixed one.
+ // In general we might have tried many suffixes; showing
+ // just one is misleading. See also golang.org/issue/6324.
+ err.Name = name
+ }
+ return dnsmessage.Parser{}, "", err
+}
+
+// avoidDNS reports whether this is a hostname for which we should not
+// use DNS. Currently this includes only .onion, per RFC 7686. See
+// golang.org/issue/13705. Does not cover .local names (RFC 6762),
+// see golang.org/issue/16739.
+func avoidDNS(name string) bool {
+ if name == "" {
+ return true
+ }
+ name = stringslite.TrimSuffix(name, ".")
+ return stringsHasSuffixFold(name, ".onion")
+}
+
+// nameList returns a list of names for sequential DNS queries.
+func (conf *dnsConfig) nameList(name string) []string {
+ // Check name length (see isDomainName).
+ l := len(name)
+ rooted := l > 0 && name[l-1] == '.'
+ if l > 254 || l == 254 && !rooted {
+ return nil
+ }
+
+ // If name is rooted (trailing dot), try only that name.
+ if rooted {
+ if avoidDNS(name) {
+ return nil
+ }
+ return []string{name}
+ }
+
+ hasNdots := bytealg.CountString(name, '.') >= conf.ndots
+ name += "."
+ l++
+
+ // Build list of search choices.
+ names := make([]string, 0, 1+len(conf.search))
+ // If name has enough dots, try unsuffixed first.
+ if hasNdots && !avoidDNS(name) {
+ names = append(names, name)
+ }
+ // Try suffixes that are not too long (see isDomainName).
+ for _, suffix := range conf.search {
+ fqdn := name + suffix
+ if !avoidDNS(fqdn) && len(fqdn) <= 254 {
+ names = append(names, fqdn)
+ }
+ }
+ // Try unsuffixed, if not tried first above.
+ if !hasNdots && !avoidDNS(name) {
+ names = append(names, name)
+ }
+ return names
+}
+
+// hostLookupOrder specifies the order of LookupHost lookup strategies.
+// It is basically a simplified representation of nsswitch.conf.
+// "files" means /etc/hosts.
+type hostLookupOrder int
+
+const (
+ // hostLookupCgo means defer to cgo.
+ hostLookupCgo hostLookupOrder = iota
+ hostLookupFilesDNS // files first
+ hostLookupDNSFiles // dns first
+ hostLookupFiles // only files
+ hostLookupDNS // only DNS
+)
+
+var lookupOrderName = map[hostLookupOrder]string{
+ hostLookupCgo: "cgo",
+ hostLookupFilesDNS: "files,dns",
+ hostLookupDNSFiles: "dns,files",
+ hostLookupFiles: "files",
+ hostLookupDNS: "dns",
+}
+
+func (o hostLookupOrder) String() string {
+ if s, ok := lookupOrderName[o]; ok {
+ return s
+ }
+ return "hostLookupOrder=" + strconv.Itoa(int(o)) + "??"
+}
+
+func (r *Resolver) goLookupHostOrder(ctx context.Context, name string, order hostLookupOrder, conf *dnsConfig) (addrs []string, err error) {
+ if order == hostLookupFilesDNS || order == hostLookupFiles {
+ // Use entries from /etc/hosts if they match.
+ addrs, _ = lookupStaticHost(name)
+ if len(addrs) > 0 {
+ return
+ }
+
+ if order == hostLookupFiles {
+ return nil, newDNSError(errNoSuchHost, name, "")
+ }
+ }
+ ips, _, err := r.goLookupIPCNAMEOrder(ctx, "ip", name, order, conf)
+ if err != nil {
+ return
+ }
+ addrs = make([]string, 0, len(ips))
+ for _, ip := range ips {
+ addrs = append(addrs, ip.String())
+ }
+ return
+}
+
+// lookup entries from /etc/hosts
+func goLookupIPFiles(name string) (addrs []IPAddr, canonical string) {
+ addr, canonical := lookupStaticHost(name)
+ for _, haddr := range addr {
+ haddr, zone := splitHostZone(haddr)
+ if ip := ParseIP(haddr); ip != nil {
+ addr := IPAddr{IP: ip, Zone: zone}
+ addrs = append(addrs, addr)
+ }
+ }
+ sortByRFC6724(addrs)
+ return addrs, canonical
+}
+
+// goLookupIP is the native Go implementation of LookupIP.
+// The libc versions are in cgo_*.go.
+func (r *Resolver) goLookupIP(ctx context.Context, network, host string, order hostLookupOrder, conf *dnsConfig) (addrs []IPAddr, err error) {
+ addrs, _, err = r.goLookupIPCNAMEOrder(ctx, network, host, order, conf)
+ return
+}
+
+func (r *Resolver) goLookupIPCNAMEOrder(ctx context.Context, network, name string, order hostLookupOrder, conf *dnsConfig) (addrs []IPAddr, cname dnsmessage.Name, err error) {
+ if order == hostLookupFilesDNS || order == hostLookupFiles {
+ var canonical string
+ addrs, canonical = goLookupIPFiles(name)
+
+ if len(addrs) > 0 {
+ var err error
+ cname, err = dnsmessage.NewName(canonical)
+ if err != nil {
+ return nil, dnsmessage.Name{}, err
+ }
+ return addrs, cname, nil
+ }
+
+ if order == hostLookupFiles {
+ return nil, dnsmessage.Name{}, newDNSError(errNoSuchHost, name, "")
+ }
+ }
+
+ if !isDomainName(name) {
+ // See comment in func lookup above about use of errNoSuchHost.
+ return nil, dnsmessage.Name{}, newDNSError(errNoSuchHost, name, "")
+ }
+ type result struct {
+ p dnsmessage.Parser
+ server string
+ error
+ }
+
+ if conf == nil {
+ conf = getSystemDNSConfig()
+ }
+
+ lane := make(chan result, 1)
+ qtypes := []dnsmessage.Type{dnsmessage.TypeA, dnsmessage.TypeAAAA}
+ if network == "CNAME" {
+ qtypes = append(qtypes, dnsmessage.TypeCNAME)
+ }
+ switch ipVersion(network) {
+ case '4':
+ qtypes = []dnsmessage.Type{dnsmessage.TypeA}
+ case '6':
+ qtypes = []dnsmessage.Type{dnsmessage.TypeAAAA}
+ }
+ var queryFn func(fqdn string, qtype dnsmessage.Type)
+ var responseFn func(fqdn string, qtype dnsmessage.Type) result
+ if conf.singleRequest {
+ queryFn = func(fqdn string, qtype dnsmessage.Type) {}
+ responseFn = func(fqdn string, qtype dnsmessage.Type) result {
+ dnsWaitGroup.Add(1)
+ defer dnsWaitGroup.Done()
+ p, server, err := r.tryOneName(ctx, conf, fqdn, qtype)
+ return result{p, server, err}
+ }
+ } else {
+ queryFn = func(fqdn string, qtype dnsmessage.Type) {
+ dnsWaitGroup.Add(1)
+ go func(qtype dnsmessage.Type) {
+ p, server, err := r.tryOneName(ctx, conf, fqdn, qtype)
+ lane <- result{p, server, err}
+ dnsWaitGroup.Done()
+ }(qtype)
+ }
+ responseFn = func(fqdn string, qtype dnsmessage.Type) result {
+ return <-lane
+ }
+ }
+ var lastErr error
+ for _, fqdn := range conf.nameList(name) {
+ for _, qtype := range qtypes {
+ queryFn(fqdn, qtype)
+ }
+ hitStrictError := false
+ for _, qtype := range qtypes {
+ result := responseFn(fqdn, qtype)
+ if result.error != nil {
+ if nerr, ok := result.error.(Error); ok && nerr.Temporary() && r.strictErrors() {
+ // This error will abort the nameList loop.
+ hitStrictError = true
+ lastErr = result.error
+ } else if lastErr == nil || fqdn == name+"." {
+ // Prefer error for original name.
+ lastErr = result.error
+ }
+ continue
+ }
+
+ // Presotto says it's okay to assume that servers listed in
+ // /etc/resolv.conf are recursive resolvers.
+ //
+ // We asked for recursion, so it should have included all the
+ // answers we need in this one packet.
+ //
+ // Further, RFC 1034 section 4.3.1 says that "the recursive
+ // response to a query will be... The answer to the query,
+ // possibly preface by one or more CNAME RRs that specify
+ // aliases encountered on the way to an answer."
+ //
+ // Therefore, we should be able to assume that we can ignore
+ // CNAMEs and that the A and AAAA records we requested are
+ // for the canonical name.
+
+ loop:
+ for {
+ h, err := result.p.AnswerHeader()
+ if err != nil && err != dnsmessage.ErrSectionDone {
+ lastErr = &DNSError{
+ Err: errCannotUnmarshalDNSMessage.Error(),
+ Name: name,
+ Server: result.server,
+ }
+ }
+ if err != nil {
+ break
+ }
+ switch h.Type {
+ case dnsmessage.TypeA:
+ a, err := result.p.AResource()
+ if err != nil {
+ lastErr = &DNSError{
+ Err: errCannotUnmarshalDNSMessage.Error(),
+ Name: name,
+ Server: result.server,
+ }
+ break loop
+ }
+ addrs = append(addrs, IPAddr{IP: IP(a.A[:])})
+ if cname.Length == 0 && h.Name.Length != 0 {
+ cname = h.Name
+ }
+
+ case dnsmessage.TypeAAAA:
+ aaaa, err := result.p.AAAAResource()
+ if err != nil {
+ lastErr = &DNSError{
+ Err: errCannotUnmarshalDNSMessage.Error(),
+ Name: name,
+ Server: result.server,
+ }
+ break loop
+ }
+ addrs = append(addrs, IPAddr{IP: IP(aaaa.AAAA[:])})
+ if cname.Length == 0 && h.Name.Length != 0 {
+ cname = h.Name
+ }
+
+ case dnsmessage.TypeCNAME:
+ c, err := result.p.CNAMEResource()
+ if err != nil {
+ lastErr = &DNSError{
+ Err: errCannotUnmarshalDNSMessage.Error(),
+ Name: name,
+ Server: result.server,
+ }
+ break loop
+ }
+ if cname.Length == 0 && c.CNAME.Length > 0 {
+ cname = c.CNAME
+ }
+
+ default:
+ if err := result.p.SkipAnswer(); err != nil {
+ lastErr = &DNSError{
+ Err: errCannotUnmarshalDNSMessage.Error(),
+ Name: name,
+ Server: result.server,
+ }
+ break loop
+ }
+ continue
+ }
+ }
+ }
+ if hitStrictError {
+ // If either family hit an error with StrictErrors enabled,
+ // discard all addresses. This ensures that network flakiness
+ // cannot turn a dualstack hostname IPv4/IPv6-only.
+ addrs = nil
+ break
+ }
+ if len(addrs) > 0 || network == "CNAME" && cname.Length > 0 {
+ break
+ }
+ }
+ if lastErr, ok := lastErr.(*DNSError); ok {
+ // Show original name passed to lookup, not suffixed one.
+ // In general we might have tried many suffixes; showing
+ // just one is misleading. See also golang.org/issue/6324.
+ lastErr.Name = name
+ }
+ sortByRFC6724(addrs)
+ if len(addrs) == 0 && !(network == "CNAME" && cname.Length > 0) {
+ if order == hostLookupDNSFiles {
+ var canonical string
+ addrs, canonical = goLookupIPFiles(name)
+ if len(addrs) > 0 {
+ var err error
+ cname, err = dnsmessage.NewName(canonical)
+ if err != nil {
+ return nil, dnsmessage.Name{}, err
+ }
+ return addrs, cname, nil
+ }
+ }
+ if lastErr != nil {
+ return nil, dnsmessage.Name{}, lastErr
+ }
+ }
+ return addrs, cname, nil
+}
+
+// goLookupCNAME is the native Go (non-cgo) implementation of LookupCNAME.
+func (r *Resolver) goLookupCNAME(ctx context.Context, host string, order hostLookupOrder, conf *dnsConfig) (string, error) {
+ _, cname, err := r.goLookupIPCNAMEOrder(ctx, "CNAME", host, order, conf)
+ return cname.String(), err
+}
+
+// goLookupPTR is the native Go implementation of LookupAddr.
+func (r *Resolver) goLookupPTR(ctx context.Context, addr string, order hostLookupOrder, conf *dnsConfig) ([]string, error) {
+ if order == hostLookupFiles || order == hostLookupFilesDNS {
+ names := lookupStaticAddr(addr)
+ if len(names) > 0 {
+ return names, nil
+ }
+
+ if order == hostLookupFiles {
+ return nil, newDNSError(errNoSuchHost, addr, "")
+ }
+ }
+
+ arpa, err := reverseaddr(addr)
+ if err != nil {
+ return nil, err
+ }
+ p, server, err := r.lookup(ctx, arpa, dnsmessage.TypePTR, conf)
+ if err != nil {
+ if dnsErr, ok := errors.AsType[*DNSError](err); ok && dnsErr.IsNotFound {
+ if order == hostLookupDNSFiles {
+ names := lookupStaticAddr(addr)
+ if len(names) > 0 {
+ return names, nil
+ }
+ }
+ }
+ return nil, err
+ }
+ var ptrs []string
+ for {
+ h, err := p.AnswerHeader()
+ if err == dnsmessage.ErrSectionDone {
+ break
+ }
+ if err != nil {
+ return nil, &DNSError{
+ Err: errCannotUnmarshalDNSMessage.Error(),
+ Name: addr,
+ Server: server,
+ }
+ }
+ if h.Type != dnsmessage.TypePTR {
+ err := p.SkipAnswer()
+ if err != nil {
+ return nil, &DNSError{
+ Err: errCannotUnmarshalDNSMessage.Error(),
+ Name: addr,
+ Server: server,
+ }
+ }
+ continue
+ }
+ ptr, err := p.PTRResource()
+ if err != nil {
+ return nil, &DNSError{
+ Err: errCannotUnmarshalDNSMessage.Error(),
+ Name: addr,
+ Server: server,
+ }
+ }
+ ptrs = append(ptrs, ptr.PTR.String())
+
+ }
+
+ return ptrs, nil
+}
diff --git a/go/src/net/dnsclient_unix_test.go b/go/src/net/dnsclient_unix_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..fc1d40f18b6f9a75c9e5daf506991bd8bf6340b9
--- /dev/null
+++ b/go/src/net/dnsclient_unix_test.go
@@ -0,0 +1,2857 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+package net
+
+import (
+ "context"
+ "errors"
+ "fmt"
+ "maps"
+ "os"
+ "path"
+ "path/filepath"
+ "reflect"
+ "runtime"
+ "slices"
+ "strings"
+ "sync"
+ "sync/atomic"
+ "testing"
+ "time"
+
+ "golang.org/x/net/dns/dnsmessage"
+)
+
+// Test address from 192.0.2.0/24 block, reserved by RFC 5737 for documentation.
+var TestAddr = [4]byte{0xc0, 0x00, 0x02, 0x01}
+
+// Test address from 2001:db8::/32 block, reserved by RFC 3849 for documentation.
+var TestAddr6 = [16]byte{0x20, 0x01, 0x0d, 0xb8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}
+
+func mustNewName(name string) dnsmessage.Name {
+ nn, err := dnsmessage.NewName(name)
+ if err != nil {
+ panic(fmt.Sprint("creating name: ", err))
+ }
+ return nn
+}
+
+func mustQuestion(name string, qtype dnsmessage.Type, class dnsmessage.Class) dnsmessage.Question {
+ return dnsmessage.Question{
+ Name: mustNewName(name),
+ Type: qtype,
+ Class: class,
+ }
+}
+
+var dnsTransportFallbackTests = []struct {
+ server string
+ question dnsmessage.Question
+ timeout int
+ rcode dnsmessage.RCode
+}{
+ // Querying "com." with qtype=255 usually makes an answer
+ // which requires more than 512 bytes.
+ {"8.8.8.8:53", mustQuestion("com.", dnsmessage.TypeALL, dnsmessage.ClassINET), 2, dnsmessage.RCodeSuccess},
+ {"8.8.4.4:53", mustQuestion("com.", dnsmessage.TypeALL, dnsmessage.ClassINET), 4, dnsmessage.RCodeSuccess},
+}
+
+func TestDNSTransportFallback(t *testing.T) {
+ fake := fakeDNSServer{
+ rh: func(n, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ r := dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.Header.ID,
+ Response: true,
+ RCode: dnsmessage.RCodeSuccess,
+ },
+ Questions: q.Questions,
+ }
+ if n == "udp" {
+ r.Header.Truncated = true
+ }
+ return r, nil
+ },
+ }
+ r := Resolver{PreferGo: true, Dial: fake.DialContext}
+ for _, tt := range dnsTransportFallbackTests {
+ ctx, cancel := context.WithCancel(context.Background())
+ defer cancel()
+ _, h, err := r.exchange(ctx, tt.server, tt.question, time.Second, useUDPOrTCP, false)
+ if err != nil {
+ t.Error(err)
+ continue
+ }
+ if h.RCode != tt.rcode {
+ t.Errorf("got %v from %v; want %v", h.RCode, tt.server, tt.rcode)
+ continue
+ }
+ }
+}
+
+func TestDNSTransportNoFallbackOnTCP(t *testing.T) {
+ fake := fakeDNSServer{
+ rh: func(n, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ r := dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.Header.ID,
+ Response: true,
+ RCode: dnsmessage.RCodeSuccess,
+ Truncated: true,
+ },
+ Questions: q.Questions,
+ }
+ if n == "tcp" {
+ r.Answers = []dnsmessage.Resource{
+ {
+ Header: dnsmessage.ResourceHeader{
+ Name: q.Questions[0].Name,
+ Type: dnsmessage.TypeA,
+ Class: dnsmessage.ClassINET,
+ Length: 4,
+ },
+ Body: &dnsmessage.AResource{
+ A: TestAddr,
+ },
+ },
+ }
+ }
+ return r, nil
+ },
+ }
+ r := Resolver{PreferGo: true, Dial: fake.DialContext}
+ for _, tt := range dnsTransportFallbackTests {
+ ctx, cancel := context.WithCancel(context.Background())
+ defer cancel()
+ p, h, err := r.exchange(ctx, tt.server, tt.question, time.Second, useUDPOrTCP, false)
+ if err != nil {
+ t.Error(err)
+ continue
+ }
+ if h.RCode != tt.rcode {
+ t.Errorf("got %v from %v; want %v", h.RCode, tt.server, tt.rcode)
+ continue
+ }
+ a, err := p.AllAnswers()
+ if err != nil {
+ t.Errorf("unexpected error %v getting all answers from %v", err, tt.server)
+ continue
+ }
+ if len(a) != 1 {
+ t.Errorf("got %d answers from %v; want 1", len(a), tt.server)
+ continue
+ }
+ }
+}
+
+// See RFC 6761 for further information about the reserved, pseudo
+// domain names.
+var specialDomainNameTests = []struct {
+ question dnsmessage.Question
+ rcode dnsmessage.RCode
+}{
+ // Name resolution APIs and libraries should not recognize the
+ // followings as special.
+ {mustQuestion("1.0.168.192.in-addr.arpa.", dnsmessage.TypePTR, dnsmessage.ClassINET), dnsmessage.RCodeNameError},
+ {mustQuestion("test.", dnsmessage.TypeALL, dnsmessage.ClassINET), dnsmessage.RCodeNameError},
+ {mustQuestion("example.com.", dnsmessage.TypeALL, dnsmessage.ClassINET), dnsmessage.RCodeSuccess},
+
+ // Name resolution APIs and libraries should recognize the
+ // followings as special and should not send any queries.
+ // Though, we test those names here for verifying negative
+ // answers at DNS query-response interaction level.
+ {mustQuestion("localhost.", dnsmessage.TypeALL, dnsmessage.ClassINET), dnsmessage.RCodeNameError},
+ {mustQuestion("invalid.", dnsmessage.TypeALL, dnsmessage.ClassINET), dnsmessage.RCodeNameError},
+}
+
+func TestSpecialDomainName(t *testing.T) {
+ fake := fakeDNSServer{rh: func(_, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ r := dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.ID,
+ Response: true,
+ },
+ Questions: q.Questions,
+ }
+
+ switch q.Questions[0].Name.String() {
+ case "example.com.":
+ r.Header.RCode = dnsmessage.RCodeSuccess
+ default:
+ r.Header.RCode = dnsmessage.RCodeNameError
+ }
+
+ return r, nil
+ }}
+ r := Resolver{PreferGo: true, Dial: fake.DialContext}
+ server := "8.8.8.8:53"
+ for _, tt := range specialDomainNameTests {
+ ctx, cancel := context.WithCancel(context.Background())
+ defer cancel()
+ _, h, err := r.exchange(ctx, server, tt.question, 3*time.Second, useUDPOrTCP, false)
+ if err != nil {
+ t.Error(err)
+ continue
+ }
+ if h.RCode != tt.rcode {
+ t.Errorf("got %v from %v; want %v", h.RCode, server, tt.rcode)
+ continue
+ }
+ }
+}
+
+// Issue 13705: don't try to resolve onion addresses, etc
+func TestAvoidDNSName(t *testing.T) {
+ tests := []struct {
+ name string
+ avoid bool
+ }{
+ {"foo.com", false},
+ {"foo.com.", false},
+
+ {"foo.onion.", true},
+ {"foo.onion", true},
+ {"foo.ONION", true},
+ {"foo.ONION.", true},
+
+ // But do resolve *.local address; Issue 16739
+ {"foo.local.", false},
+ {"foo.local", false},
+ {"foo.LOCAL", false},
+ {"foo.LOCAL.", false},
+
+ {"", true}, // will be rejected earlier too
+
+ // Without stuff before onion/local, they're fine to
+ // use DNS. With a search path,
+ // "onion.vegetables.com" can use DNS. Without a
+ // search path (or with a trailing dot), the queries
+ // are just kinda useless, but don't reveal anything
+ // private.
+ {"local", false},
+ {"onion", false},
+ {"local.", false},
+ {"onion.", false},
+ }
+ for _, tt := range tests {
+ got := avoidDNS(tt.name)
+ if got != tt.avoid {
+ t.Errorf("avoidDNS(%q) = %v; want %v", tt.name, got, tt.avoid)
+ }
+ }
+}
+
+func TestNameListAvoidDNS(t *testing.T) {
+ c := &dnsConfig{search: []string{"go.dev.", "onion."}}
+ got := c.nameList("www")
+ if !slices.Equal(got, []string{"www.", "www.go.dev."}) {
+ t.Fatalf(`nameList("www") = %v, want "www.", "www.go.dev."`, got)
+ }
+
+ got = c.nameList("www.onion")
+ if !slices.Equal(got, []string{"www.onion.go.dev."}) {
+ t.Fatalf(`nameList("www.onion") = %v, want "www.onion.go.dev."`, got)
+ }
+}
+
+var fakeDNSServerSuccessful = fakeDNSServer{rh: func(_, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ r := dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.ID,
+ Response: true,
+ },
+ Questions: q.Questions,
+ }
+ if len(q.Questions) == 1 && q.Questions[0].Type == dnsmessage.TypeA {
+ r.Answers = []dnsmessage.Resource{
+ {
+ Header: dnsmessage.ResourceHeader{
+ Name: q.Questions[0].Name,
+ Type: dnsmessage.TypeA,
+ Class: dnsmessage.ClassINET,
+ Length: 4,
+ },
+ Body: &dnsmessage.AResource{
+ A: TestAddr,
+ },
+ },
+ }
+ }
+ return r, nil
+}}
+
+// Issue 13705: don't try to resolve onion addresses, etc
+func TestLookupTorOnion(t *testing.T) {
+ defer dnsWaitGroup.Wait()
+ r := Resolver{PreferGo: true, Dial: fakeDNSServerSuccessful.DialContext}
+ addrs, err := r.LookupIPAddr(context.Background(), "foo.onion.")
+ if err != nil {
+ t.Fatalf("lookup = %v; want nil", err)
+ }
+ if len(addrs) > 0 {
+ t.Errorf("unexpected addresses: %v", addrs)
+ }
+}
+
+type resolvConfTest struct {
+ dir string
+ path string
+ *resolverConfig
+}
+
+func newResolvConfTest() (*resolvConfTest, error) {
+ dir, err := os.MkdirTemp("", "go-resolvconftest")
+ if err != nil {
+ return nil, err
+ }
+ conf := &resolvConfTest{
+ dir: dir,
+ path: path.Join(dir, "resolv.conf"),
+ resolverConfig: &resolvConf,
+ }
+ conf.initOnce.Do(conf.init)
+ return conf, nil
+}
+
+func (conf *resolvConfTest) write(lines []string) error {
+ f, err := os.OpenFile(conf.path, os.O_CREATE|os.O_TRUNC|os.O_WRONLY, 0600)
+ if err != nil {
+ return err
+ }
+ if _, err := f.WriteString(strings.Join(lines, "\n")); err != nil {
+ f.Close()
+ return err
+ }
+ f.Close()
+ return nil
+}
+
+func (conf *resolvConfTest) writeAndUpdate(lines []string) error {
+ return conf.writeAndUpdateWithLastCheckedTime(lines, time.Now().Add(time.Hour))
+}
+
+func (conf *resolvConfTest) writeAndUpdateWithLastCheckedTime(lines []string, lastChecked time.Time) error {
+ if err := conf.write(lines); err != nil {
+ return err
+ }
+ return conf.forceUpdate(conf.path, lastChecked)
+}
+
+func (conf *resolvConfTest) forceUpdate(name string, lastChecked time.Time) error {
+ dnsConf := dnsReadConfig(name)
+ if !conf.forceUpdateConf(dnsConf, lastChecked) {
+ return fmt.Errorf("tryAcquireSema for %s failed", name)
+ }
+ return nil
+}
+
+func (conf *resolvConfTest) forceUpdateConf(c *dnsConfig, lastChecked time.Time) bool {
+ conf.dnsConfig.Store(c)
+ for i := 0; i < 5; i++ {
+ if conf.tryAcquireSema() {
+ conf.lastChecked = lastChecked
+ conf.releaseSema()
+ return true
+ }
+ }
+ return false
+}
+
+func (conf *resolvConfTest) servers() []string {
+ return conf.dnsConfig.Load().servers
+}
+
+func (conf *resolvConfTest) teardown() error {
+ err := conf.forceUpdate("/etc/resolv.conf", time.Time{})
+ os.RemoveAll(conf.dir)
+ return err
+}
+
+var updateResolvConfTests = []struct {
+ name string // query name
+ lines []string // resolver configuration lines
+ servers []string // expected name servers
+}{
+ {
+ name: "golang.org",
+ lines: []string{"nameserver 8.8.8.8"},
+ servers: []string{"8.8.8.8:53"},
+ },
+ {
+ name: "",
+ lines: nil, // an empty resolv.conf should use defaultNS as name servers
+ servers: defaultNS,
+ },
+ {
+ name: "www.example.com",
+ lines: []string{"nameserver 8.8.4.4"},
+ servers: []string{"8.8.4.4:53"},
+ },
+}
+
+func TestUpdateResolvConf(t *testing.T) {
+ defer dnsWaitGroup.Wait()
+
+ r := Resolver{PreferGo: true, Dial: fakeDNSServerSuccessful.DialContext}
+
+ conf, err := newResolvConfTest()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer conf.teardown()
+
+ for i, tt := range updateResolvConfTests {
+ if err := conf.writeAndUpdate(tt.lines); err != nil {
+ t.Error(err)
+ continue
+ }
+ if tt.name != "" {
+ var wg sync.WaitGroup
+ const N = 10
+ wg.Add(N)
+ for j := 0; j < N; j++ {
+ go func(name string) {
+ defer wg.Done()
+ ips, err := r.LookupIPAddr(context.Background(), name)
+ if err != nil {
+ t.Error(err)
+ return
+ }
+ if len(ips) == 0 {
+ t.Errorf("no records for %s", name)
+ return
+ }
+ }(tt.name)
+ }
+ wg.Wait()
+ }
+ servers := conf.servers()
+ if !slices.Equal(servers, tt.servers) {
+ t.Errorf("#%d: got %v; want %v", i, servers, tt.servers)
+ continue
+ }
+ }
+}
+
+var goLookupIPWithResolverConfigTests = []struct {
+ name string
+ lines []string // resolver configuration lines
+ error
+ a, aaaa bool // whether response contains A, AAAA-record
+}{
+ // no records, transport timeout
+ {
+ "jgahvsekduiv9bw4b3qhn4ykdfgj0493iohkrjfhdvhjiu4j",
+ []string{
+ "options timeout:1 attempts:1",
+ "nameserver 255.255.255.255", // please forgive us for abuse of limited broadcast address
+ },
+ &DNSError{Name: "jgahvsekduiv9bw4b3qhn4ykdfgj0493iohkrjfhdvhjiu4j", Server: "255.255.255.255:53", IsTimeout: true},
+ false, false,
+ },
+
+ // no records, non-existent domain
+ {
+ "jgahvsekduiv9bw4b3qhn4ykdfgj0493iohkrjfhdvhjiu4j",
+ []string{
+ "options timeout:3 attempts:1",
+ "nameserver 8.8.8.8",
+ },
+ &DNSError{Name: "jgahvsekduiv9bw4b3qhn4ykdfgj0493iohkrjfhdvhjiu4j", Server: "8.8.8.8:53", IsTimeout: false},
+ false, false,
+ },
+
+ // a few A records, no AAAA records
+ {
+ "ipv4.google.com.",
+ []string{
+ "nameserver 8.8.8.8",
+ "nameserver 2001:4860:4860::8888",
+ },
+ nil,
+ true, false,
+ },
+ {
+ "ipv4.google.com",
+ []string{
+ "domain golang.org",
+ "nameserver 2001:4860:4860::8888",
+ "nameserver 8.8.8.8",
+ },
+ nil,
+ true, false,
+ },
+ {
+ "ipv4.google.com",
+ []string{
+ "search x.golang.org y.golang.org",
+ "nameserver 2001:4860:4860::8888",
+ "nameserver 8.8.8.8",
+ },
+ nil,
+ true, false,
+ },
+
+ // no A records, a few AAAA records
+ {
+ "ipv6.google.com.",
+ []string{
+ "nameserver 2001:4860:4860::8888",
+ "nameserver 8.8.8.8",
+ },
+ nil,
+ false, true,
+ },
+ {
+ "ipv6.google.com",
+ []string{
+ "domain golang.org",
+ "nameserver 8.8.8.8",
+ "nameserver 2001:4860:4860::8888",
+ },
+ nil,
+ false, true,
+ },
+ {
+ "ipv6.google.com",
+ []string{
+ "search x.golang.org y.golang.org",
+ "nameserver 8.8.8.8",
+ "nameserver 2001:4860:4860::8888",
+ },
+ nil,
+ false, true,
+ },
+
+ // both A and AAAA records
+ {
+ "hostname.as112.net", // see RFC 7534
+ []string{
+ "domain golang.org",
+ "nameserver 2001:4860:4860::8888",
+ "nameserver 8.8.8.8",
+ },
+ nil,
+ true, true,
+ },
+ {
+ "hostname.as112.net", // see RFC 7534
+ []string{
+ "search x.golang.org y.golang.org",
+ "nameserver 2001:4860:4860::8888",
+ "nameserver 8.8.8.8",
+ },
+ nil,
+ true, true,
+ },
+}
+
+func TestGoLookupIPWithResolverConfig(t *testing.T) {
+ defer dnsWaitGroup.Wait()
+ fake := fakeDNSServer{rh: func(n, s string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ switch s {
+ case "[2001:4860:4860::8888]:53", "8.8.8.8:53":
+ break
+ default:
+ time.Sleep(10 * time.Millisecond)
+ return dnsmessage.Message{}, os.ErrDeadlineExceeded
+ }
+ r := dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.ID,
+ Response: true,
+ },
+ Questions: q.Questions,
+ }
+ for _, question := range q.Questions {
+ switch question.Type {
+ case dnsmessage.TypeA:
+ switch question.Name.String() {
+ case "hostname.as112.net.":
+ break
+ case "ipv4.google.com.":
+ r.Answers = append(r.Answers, dnsmessage.Resource{
+ Header: dnsmessage.ResourceHeader{
+ Name: q.Questions[0].Name,
+ Type: dnsmessage.TypeA,
+ Class: dnsmessage.ClassINET,
+ Length: 4,
+ },
+ Body: &dnsmessage.AResource{
+ A: TestAddr,
+ },
+ })
+ default:
+
+ }
+ case dnsmessage.TypeAAAA:
+ switch question.Name.String() {
+ case "hostname.as112.net.":
+ break
+ case "ipv6.google.com.":
+ r.Answers = append(r.Answers, dnsmessage.Resource{
+ Header: dnsmessage.ResourceHeader{
+ Name: q.Questions[0].Name,
+ Type: dnsmessage.TypeAAAA,
+ Class: dnsmessage.ClassINET,
+ Length: 16,
+ },
+ Body: &dnsmessage.AAAAResource{
+ AAAA: TestAddr6,
+ },
+ })
+ }
+ }
+ }
+ return r, nil
+ }}
+ r := Resolver{PreferGo: true, Dial: fake.DialContext}
+
+ conf, err := newResolvConfTest()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer conf.teardown()
+
+ for _, tt := range goLookupIPWithResolverConfigTests {
+ if err := conf.writeAndUpdate(tt.lines); err != nil {
+ t.Error(err)
+ continue
+ }
+ addrs, err := r.LookupIPAddr(context.Background(), tt.name)
+ if err != nil {
+ if err, ok := err.(*DNSError); !ok || tt.error != nil && (err.Name != tt.error.(*DNSError).Name || err.Server != tt.error.(*DNSError).Server || err.IsTimeout != tt.error.(*DNSError).IsTimeout) {
+ t.Errorf("got %v; want %v", err, tt.error)
+ }
+ continue
+ }
+ if len(addrs) == 0 {
+ t.Errorf("no records for %s", tt.name)
+ }
+ if !tt.a && !tt.aaaa && len(addrs) > 0 {
+ t.Errorf("unexpected %v for %s", addrs, tt.name)
+ }
+ for _, addr := range addrs {
+ if !tt.a && addr.IP.To4() != nil {
+ t.Errorf("got %v; must not be IPv4 address", addr)
+ }
+ if !tt.aaaa && addr.IP.To16() != nil && addr.IP.To4() == nil {
+ t.Errorf("got %v; must not be IPv6 address", addr)
+ }
+ }
+ }
+}
+
+// Test that goLookupIPOrder falls back to the host file when no DNS servers are available.
+func TestGoLookupIPOrderFallbackToFile(t *testing.T) {
+ defer dnsWaitGroup.Wait()
+
+ fake := fakeDNSServer{rh: func(n, s string, q dnsmessage.Message, tm time.Time) (dnsmessage.Message, error) {
+ r := dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.ID,
+ Response: true,
+ },
+ Questions: q.Questions,
+ }
+ return r, nil
+ }}
+ r := Resolver{PreferGo: true, Dial: fake.DialContext}
+
+ // Add a config that simulates no dns servers being available.
+ conf, err := newResolvConfTest()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer conf.teardown()
+
+ if err := conf.writeAndUpdate([]string{}); err != nil {
+ t.Fatal(err)
+ }
+ // Redirect host file lookups.
+ defer func(orig string) { hostsFilePath = orig }(hostsFilePath)
+ hostsFilePath = "testdata/hosts"
+
+ for _, order := range []hostLookupOrder{hostLookupFilesDNS, hostLookupDNSFiles} {
+ name := fmt.Sprintf("order %v", order)
+ // First ensure that we get an error when contacting a non-existent host.
+ _, _, err := r.goLookupIPCNAMEOrder(context.Background(), "ip", "notarealhost", order, nil)
+ if err == nil {
+ t.Errorf("%s: expected error while looking up name not in hosts file", name)
+ continue
+ }
+
+ // Now check that we get an address when the name appears in the hosts file.
+ addrs, _, err := r.goLookupIPCNAMEOrder(context.Background(), "ip", "thor", order, nil) // entry is in "testdata/hosts"
+ if err != nil {
+ t.Errorf("%s: expected to successfully lookup host entry", name)
+ continue
+ }
+ if len(addrs) != 1 {
+ t.Errorf("%s: expected exactly one result, but got %v", name, addrs)
+ continue
+ }
+ if got, want := addrs[0].String(), "127.1.1.1"; got != want {
+ t.Errorf("%s: address doesn't match expectation. got %v, want %v", name, got, want)
+ }
+ }
+}
+
+// Issue 12712.
+// When using search domains, return the error encountered
+// querying the original name instead of an error encountered
+// querying a generated name.
+func TestErrorForOriginalNameWhenSearching(t *testing.T) {
+ defer dnsWaitGroup.Wait()
+
+ const fqdn = "doesnotexist.domain"
+
+ conf, err := newResolvConfTest()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer conf.teardown()
+
+ if err := conf.writeAndUpdate([]string{"search servfail"}); err != nil {
+ t.Fatal(err)
+ }
+
+ fake := fakeDNSServer{rh: func(_, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ r := dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.ID,
+ Response: true,
+ },
+ Questions: q.Questions,
+ }
+
+ switch q.Questions[0].Name.String() {
+ case fqdn + ".servfail.":
+ r.Header.RCode = dnsmessage.RCodeServerFailure
+ default:
+ r.Header.RCode = dnsmessage.RCodeNameError
+ }
+
+ return r, nil
+ }}
+
+ cases := []struct {
+ strictErrors bool
+ wantErr *DNSError
+ }{
+ {true, &DNSError{Name: fqdn, Err: "server misbehaving", IsTemporary: true}},
+ {false, &DNSError{Name: fqdn, Err: errNoSuchHost.Error(), IsNotFound: true}},
+ }
+ for _, tt := range cases {
+ r := Resolver{PreferGo: true, StrictErrors: tt.strictErrors, Dial: fake.DialContext}
+ _, err = r.LookupIPAddr(context.Background(), fqdn)
+ if err == nil {
+ t.Fatal("expected an error")
+ }
+
+ want := tt.wantErr
+ if err, ok := err.(*DNSError); !ok || err.Name != want.Name || err.Err != want.Err || err.IsTemporary != want.IsTemporary {
+ t.Errorf("got %v; want %v", err, want)
+ }
+ }
+}
+
+// Issue 15434. If a name server gives a lame referral, continue to the next.
+func TestIgnoreLameReferrals(t *testing.T) {
+ defer dnsWaitGroup.Wait()
+
+ conf, err := newResolvConfTest()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer conf.teardown()
+
+ if err := conf.writeAndUpdate([]string{"nameserver 192.0.2.1", // the one that will give a lame referral
+ "nameserver 192.0.2.2"}); err != nil {
+ t.Fatal(err)
+ }
+
+ fake := fakeDNSServer{rh: func(_, s string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ t.Log(s, q)
+ r := dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.ID,
+ Response: true,
+ },
+ Questions: q.Questions,
+ }
+
+ if s == "192.0.2.2:53" {
+ r.Header.RecursionAvailable = true
+ if q.Questions[0].Type == dnsmessage.TypeA {
+ r.Answers = []dnsmessage.Resource{
+ {
+ Header: dnsmessage.ResourceHeader{
+ Name: q.Questions[0].Name,
+ Type: dnsmessage.TypeA,
+ Class: dnsmessage.ClassINET,
+ Length: 4,
+ },
+ Body: &dnsmessage.AResource{
+ A: TestAddr,
+ },
+ },
+ }
+ }
+ } else if s == "192.0.2.1:53" {
+ if q.Questions[0].Type == dnsmessage.TypeA && strings.HasPrefix(q.Questions[0].Name.String(), "empty.com.") {
+ var edns0Hdr dnsmessage.ResourceHeader
+ edns0Hdr.SetEDNS0(maxDNSPacketSize, dnsmessage.RCodeSuccess, false)
+
+ r.Additionals = []dnsmessage.Resource{
+ {
+ Header: edns0Hdr,
+ Body: &dnsmessage.OPTResource{},
+ },
+ }
+ }
+ }
+
+ return r, nil
+ }}
+ r := Resolver{PreferGo: true, Dial: fake.DialContext}
+
+ addrs, err := r.LookupIP(context.Background(), "ip4", "www.golang.org")
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ if got := len(addrs); got != 1 {
+ t.Fatalf("got %d addresses, want 1", got)
+ }
+
+ if got, want := addrs[0].String(), "192.0.2.1"; got != want {
+ t.Fatalf("got address %v, want %v", got, want)
+ }
+
+ _, err = r.LookupIP(context.Background(), "ip4", "empty.com")
+ de, ok := err.(*DNSError)
+ if !ok {
+ t.Fatalf("err = %#v; wanted a *net.DNSError", err)
+ }
+ if de.Err != errNoSuchHost.Error() {
+ t.Fatalf("Err = %#v; wanted %q", de.Err, errNoSuchHost.Error())
+ }
+}
+
+func BenchmarkGoLookupIP(b *testing.B) {
+ testHookUninstaller.Do(uninstallTestHooks)
+ ctx := context.Background()
+ b.ReportAllocs()
+
+ for i := 0; i < b.N; i++ {
+ goResolver.LookupIPAddr(ctx, "www.example.com")
+ }
+}
+
+func BenchmarkGoLookupIPNoSuchHost(b *testing.B) {
+ testHookUninstaller.Do(uninstallTestHooks)
+ ctx := context.Background()
+ b.ReportAllocs()
+
+ for i := 0; i < b.N; i++ {
+ goResolver.LookupIPAddr(ctx, "some.nonexistent")
+ }
+}
+
+func BenchmarkGoLookupIPWithBrokenNameServer(b *testing.B) {
+ testHookUninstaller.Do(uninstallTestHooks)
+
+ conf, err := newResolvConfTest()
+ if err != nil {
+ b.Fatal(err)
+ }
+ defer conf.teardown()
+
+ lines := []string{
+ "nameserver 203.0.113.254", // use TEST-NET-3 block, see RFC 5737
+ "nameserver 8.8.8.8",
+ }
+ if err := conf.writeAndUpdate(lines); err != nil {
+ b.Fatal(err)
+ }
+ ctx := context.Background()
+ b.ReportAllocs()
+
+ for i := 0; i < b.N; i++ {
+ goResolver.LookupIPAddr(ctx, "www.example.com")
+ }
+}
+
+type fakeDNSServer struct {
+ rh func(n, s string, q dnsmessage.Message, t time.Time) (dnsmessage.Message, error)
+ alwaysTCP bool
+}
+
+func (server *fakeDNSServer) DialContext(_ context.Context, n, s string) (Conn, error) {
+ if server.alwaysTCP || n == "tcp" || n == "tcp4" || n == "tcp6" {
+ return &fakeDNSConn{tcp: true, server: server, n: n, s: s}, nil
+ }
+ return &fakeDNSPacketConn{fakeDNSConn: fakeDNSConn{tcp: false, server: server, n: n, s: s}}, nil
+}
+
+type fakeDNSConn struct {
+ Conn
+ tcp bool
+ server *fakeDNSServer
+ n string
+ s string
+ q dnsmessage.Message
+ t time.Time
+ buf []byte
+}
+
+func (f *fakeDNSConn) Close() error {
+ return nil
+}
+
+func (f *fakeDNSConn) Read(b []byte) (int, error) {
+ if len(f.buf) > 0 {
+ n := copy(b, f.buf)
+ f.buf = f.buf[n:]
+ return n, nil
+ }
+
+ resp, err := f.server.rh(f.n, f.s, f.q, f.t)
+ if err != nil {
+ return 0, err
+ }
+
+ bb := make([]byte, 2, 514)
+ bb, err = resp.AppendPack(bb)
+ if err != nil {
+ return 0, fmt.Errorf("cannot marshal DNS message: %v", err)
+ }
+
+ if f.tcp {
+ l := len(bb) - 2
+ bb[0] = byte(l >> 8)
+ bb[1] = byte(l)
+ f.buf = bb
+ return f.Read(b)
+ }
+
+ bb = bb[2:]
+ if len(b) < len(bb) {
+ return 0, errors.New("read would fragment DNS message")
+ }
+
+ copy(b, bb)
+ return len(bb), nil
+}
+
+func (f *fakeDNSConn) Write(b []byte) (int, error) {
+ if f.tcp && len(b) >= 2 {
+ b = b[2:]
+ }
+ if f.q.Unpack(b) != nil {
+ return 0, fmt.Errorf("cannot unmarshal DNS message fake %s (%d)", f.n, len(b))
+ }
+ return len(b), nil
+}
+
+func (f *fakeDNSConn) SetDeadline(t time.Time) error {
+ f.t = t
+ return nil
+}
+
+type fakeDNSPacketConn struct {
+ PacketConn
+ fakeDNSConn
+}
+
+func (f *fakeDNSPacketConn) SetDeadline(t time.Time) error {
+ return f.fakeDNSConn.SetDeadline(t)
+}
+
+func (f *fakeDNSPacketConn) Close() error {
+ return f.fakeDNSConn.Close()
+}
+
+// UDP round-tripper algorithm should ignore invalid DNS responses (issue 13281).
+func TestIgnoreDNSForgeries(t *testing.T) {
+ c, s := Pipe()
+ go func() {
+ b := make([]byte, maxDNSPacketSize)
+ n, err := s.Read(b)
+ if err != nil {
+ t.Error(err)
+ return
+ }
+
+ var msg dnsmessage.Message
+ if msg.Unpack(b[:n]) != nil {
+ t.Error("invalid DNS query:", err)
+ return
+ }
+
+ s.Write([]byte("garbage DNS response packet"))
+
+ msg.Header.Response = true
+ msg.Header.ID++ // make invalid ID
+
+ if b, err = msg.Pack(); err != nil {
+ t.Error("failed to pack DNS response:", err)
+ return
+ }
+ s.Write(b)
+
+ msg.Header.ID-- // restore original ID
+ msg.Answers = []dnsmessage.Resource{
+ {
+ Header: dnsmessage.ResourceHeader{
+ Name: mustNewName("www.example.com."),
+ Type: dnsmessage.TypeA,
+ Class: dnsmessage.ClassINET,
+ Length: 4,
+ },
+ Body: &dnsmessage.AResource{
+ A: TestAddr,
+ },
+ },
+ }
+
+ b, err = msg.Pack()
+ if err != nil {
+ t.Error("failed to pack DNS response:", err)
+ return
+ }
+ s.Write(b)
+ }()
+
+ msg := dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: 42,
+ },
+ Questions: []dnsmessage.Question{
+ {
+ Name: mustNewName("www.example.com."),
+ Type: dnsmessage.TypeA,
+ Class: dnsmessage.ClassINET,
+ },
+ },
+ }
+
+ b, err := msg.Pack()
+ if err != nil {
+ t.Fatal("Pack failed:", err)
+ }
+
+ p, _, err := dnsPacketRoundTrip(c, 42, msg.Questions[0], b)
+ if err != nil {
+ t.Fatalf("dnsPacketRoundTrip failed: %v", err)
+ }
+
+ p.SkipAllQuestions()
+ as, err := p.AllAnswers()
+ if err != nil {
+ t.Fatal("AllAnswers failed:", err)
+ }
+ if got := as[0].Body.(*dnsmessage.AResource).A; got != TestAddr {
+ t.Errorf("got address %v, want %v", got, TestAddr)
+ }
+}
+
+// Issue 16865. If a name server times out, continue to the next.
+func TestRetryTimeout(t *testing.T) {
+ defer dnsWaitGroup.Wait()
+
+ conf, err := newResolvConfTest()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer conf.teardown()
+
+ testConf := []string{
+ "nameserver 192.0.2.1", // the one that will timeout
+ "nameserver 192.0.2.2",
+ }
+ if err := conf.writeAndUpdate(testConf); err != nil {
+ t.Fatal(err)
+ }
+
+ var deadline0 time.Time
+
+ fake := fakeDNSServer{rh: func(_, s string, q dnsmessage.Message, deadline time.Time) (dnsmessage.Message, error) {
+ t.Log(s, q, deadline)
+
+ if deadline.IsZero() {
+ t.Error("zero deadline")
+ }
+
+ if s == "192.0.2.1:53" {
+ deadline0 = deadline
+ time.Sleep(10 * time.Millisecond)
+ return dnsmessage.Message{}, os.ErrDeadlineExceeded
+ }
+
+ if deadline.Equal(deadline0) {
+ t.Error("deadline didn't change")
+ }
+
+ return mockTXTResponse(q), nil
+ }}
+ r := &Resolver{PreferGo: true, Dial: fake.DialContext}
+
+ _, err = r.LookupTXT(context.Background(), "www.golang.org")
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ if deadline0.IsZero() {
+ t.Error("deadline0 still zero", deadline0)
+ }
+}
+
+func TestRotate(t *testing.T) {
+ // without rotation, always uses the first server
+ testRotate(t, false, []string{"192.0.2.1", "192.0.2.2"}, []string{"192.0.2.1:53", "192.0.2.1:53", "192.0.2.1:53"})
+
+ // with rotation, rotates through back to first
+ testRotate(t, true, []string{"192.0.2.1", "192.0.2.2"}, []string{"192.0.2.1:53", "192.0.2.2:53", "192.0.2.1:53"})
+}
+
+func testRotate(t *testing.T, rotate bool, nameservers, wantServers []string) {
+ defer dnsWaitGroup.Wait()
+
+ conf, err := newResolvConfTest()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer conf.teardown()
+
+ var confLines []string
+ for _, ns := range nameservers {
+ confLines = append(confLines, "nameserver "+ns)
+ }
+ if rotate {
+ confLines = append(confLines, "options rotate")
+ }
+
+ if err := conf.writeAndUpdate(confLines); err != nil {
+ t.Fatal(err)
+ }
+
+ var usedServers []string
+ fake := fakeDNSServer{rh: func(_, s string, q dnsmessage.Message, deadline time.Time) (dnsmessage.Message, error) {
+ usedServers = append(usedServers, s)
+ return mockTXTResponse(q), nil
+ }}
+ r := Resolver{PreferGo: true, Dial: fake.DialContext}
+
+ // len(nameservers) + 1 to allow rotation to get back to start
+ for i := 0; i < len(nameservers)+1; i++ {
+ if _, err := r.LookupTXT(context.Background(), "www.golang.org"); err != nil {
+ t.Fatal(err)
+ }
+ }
+
+ if !slices.Equal(usedServers, wantServers) {
+ t.Errorf("rotate=%t got used servers:\n%v\nwant:\n%v", rotate, usedServers, wantServers)
+ }
+}
+
+func mockTXTResponse(q dnsmessage.Message) dnsmessage.Message {
+ r := dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.ID,
+ Response: true,
+ RecursionAvailable: true,
+ },
+ Questions: q.Questions,
+ Answers: []dnsmessage.Resource{
+ {
+ Header: dnsmessage.ResourceHeader{
+ Name: q.Questions[0].Name,
+ Type: dnsmessage.TypeTXT,
+ Class: dnsmessage.ClassINET,
+ },
+ Body: &dnsmessage.TXTResource{
+ TXT: []string{"ok"},
+ },
+ },
+ },
+ }
+
+ return r
+}
+
+// Issue 17448. With StrictErrors enabled, temporary errors should make
+// LookupIP fail rather than return a partial result.
+func TestStrictErrorsLookupIP(t *testing.T) {
+ defer dnsWaitGroup.Wait()
+
+ conf, err := newResolvConfTest()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer conf.teardown()
+
+ confData := []string{
+ "nameserver 192.0.2.53",
+ "search x.golang.org y.golang.org",
+ }
+ if err := conf.writeAndUpdate(confData); err != nil {
+ t.Fatal(err)
+ }
+
+ const name = "test-issue19592"
+ const server = "192.0.2.53:53"
+ const searchX = "test-issue19592.x.golang.org."
+ const searchY = "test-issue19592.y.golang.org."
+ const ip4 = "192.0.2.1"
+ const ip6 = "2001:db8::1"
+
+ type resolveWhichEnum int
+ const (
+ resolveOK resolveWhichEnum = iota
+ resolveOpError
+ resolveServfail
+ resolveTimeout
+ )
+
+ makeTempError := func(err string) error {
+ return &DNSError{
+ Err: err,
+ Name: name,
+ Server: server,
+ IsTemporary: true,
+ }
+ }
+ makeTimeout := func() error {
+ return &DNSError{
+ Err: os.ErrDeadlineExceeded.Error(),
+ Name: name,
+ Server: server,
+ IsTimeout: true,
+ IsTemporary: true,
+ }
+ }
+ makeNxDomain := func() error {
+ return &DNSError{
+ Err: errNoSuchHost.Error(),
+ Name: name,
+ Server: server,
+ IsNotFound: true,
+ }
+ }
+
+ cases := []struct {
+ desc string
+ resolveWhich func(quest dnsmessage.Question) resolveWhichEnum
+ wantStrictErr error
+ wantLaxErr error
+ wantIPs []string
+ }{
+ {
+ desc: "No errors",
+ resolveWhich: func(quest dnsmessage.Question) resolveWhichEnum {
+ return resolveOK
+ },
+ wantIPs: []string{ip4, ip6},
+ },
+ {
+ desc: "searchX error fails in strict mode",
+ resolveWhich: func(quest dnsmessage.Question) resolveWhichEnum {
+ if quest.Name.String() == searchX {
+ return resolveTimeout
+ }
+ return resolveOK
+ },
+ wantStrictErr: makeTimeout(),
+ wantIPs: []string{ip4, ip6},
+ },
+ {
+ desc: "searchX IPv4-only timeout fails in strict mode",
+ resolveWhich: func(quest dnsmessage.Question) resolveWhichEnum {
+ if quest.Name.String() == searchX && quest.Type == dnsmessage.TypeA {
+ return resolveTimeout
+ }
+ return resolveOK
+ },
+ wantStrictErr: makeTimeout(),
+ wantIPs: []string{ip4, ip6},
+ },
+ {
+ desc: "searchX IPv6-only servfail fails in strict mode",
+ resolveWhich: func(quest dnsmessage.Question) resolveWhichEnum {
+ if quest.Name.String() == searchX && quest.Type == dnsmessage.TypeAAAA {
+ return resolveServfail
+ }
+ return resolveOK
+ },
+ wantStrictErr: makeTempError("server misbehaving"),
+ wantIPs: []string{ip4, ip6},
+ },
+ {
+ desc: "searchY error always fails",
+ resolveWhich: func(quest dnsmessage.Question) resolveWhichEnum {
+ if quest.Name.String() == searchY {
+ return resolveTimeout
+ }
+ return resolveOK
+ },
+ wantStrictErr: makeTimeout(),
+ wantLaxErr: makeNxDomain(), // This one reaches the "test." FQDN.
+ },
+ {
+ desc: "searchY IPv4-only socket error fails in strict mode",
+ resolveWhich: func(quest dnsmessage.Question) resolveWhichEnum {
+ if quest.Name.String() == searchY && quest.Type == dnsmessage.TypeA {
+ return resolveOpError
+ }
+ return resolveOK
+ },
+ wantStrictErr: makeTempError("write: socket on fire"),
+ wantIPs: []string{ip6},
+ },
+ {
+ desc: "searchY IPv6-only timeout fails in strict mode",
+ resolveWhich: func(quest dnsmessage.Question) resolveWhichEnum {
+ if quest.Name.String() == searchY && quest.Type == dnsmessage.TypeAAAA {
+ return resolveTimeout
+ }
+ return resolveOK
+ },
+ wantStrictErr: makeTimeout(),
+ wantIPs: []string{ip4},
+ },
+ }
+
+ for i, tt := range cases {
+ fake := fakeDNSServer{rh: func(_, s string, q dnsmessage.Message, deadline time.Time) (dnsmessage.Message, error) {
+ t.Log(s, q)
+
+ switch tt.resolveWhich(q.Questions[0]) {
+ case resolveOK:
+ // Handle below.
+ case resolveOpError:
+ return dnsmessage.Message{}, &OpError{Op: "write", Err: fmt.Errorf("socket on fire")}
+ case resolveServfail:
+ return dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.ID,
+ Response: true,
+ RCode: dnsmessage.RCodeServerFailure,
+ },
+ Questions: q.Questions,
+ }, nil
+ case resolveTimeout:
+ return dnsmessage.Message{}, os.ErrDeadlineExceeded
+ default:
+ t.Fatal("Impossible resolveWhich")
+ }
+
+ switch q.Questions[0].Name.String() {
+ case searchX, name + ".":
+ // Return NXDOMAIN to utilize the search list.
+ return dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.ID,
+ Response: true,
+ RCode: dnsmessage.RCodeNameError,
+ },
+ Questions: q.Questions,
+ }, nil
+ case searchY:
+ // Return records below.
+ default:
+ return dnsmessage.Message{}, fmt.Errorf("Unexpected Name: %v", q.Questions[0].Name)
+ }
+
+ r := dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.ID,
+ Response: true,
+ },
+ Questions: q.Questions,
+ }
+ switch q.Questions[0].Type {
+ case dnsmessage.TypeA:
+ r.Answers = []dnsmessage.Resource{
+ {
+ Header: dnsmessage.ResourceHeader{
+ Name: q.Questions[0].Name,
+ Type: dnsmessage.TypeA,
+ Class: dnsmessage.ClassINET,
+ Length: 4,
+ },
+ Body: &dnsmessage.AResource{
+ A: TestAddr,
+ },
+ },
+ }
+ case dnsmessage.TypeAAAA:
+ r.Answers = []dnsmessage.Resource{
+ {
+ Header: dnsmessage.ResourceHeader{
+ Name: q.Questions[0].Name,
+ Type: dnsmessage.TypeAAAA,
+ Class: dnsmessage.ClassINET,
+ Length: 16,
+ },
+ Body: &dnsmessage.AAAAResource{
+ AAAA: TestAddr6,
+ },
+ },
+ }
+ default:
+ return dnsmessage.Message{}, fmt.Errorf("Unexpected Type: %v", q.Questions[0].Type)
+ }
+ return r, nil
+ }}
+
+ for _, strict := range []bool{true, false} {
+ r := Resolver{PreferGo: true, StrictErrors: strict, Dial: fake.DialContext}
+ ips, err := r.LookupIPAddr(context.Background(), name)
+
+ var wantErr error
+ if strict {
+ wantErr = tt.wantStrictErr
+ } else {
+ wantErr = tt.wantLaxErr
+ }
+ if !reflect.DeepEqual(err, wantErr) {
+ t.Errorf("#%d (%s) strict=%v: got err %#v; want %#v", i, tt.desc, strict, err, wantErr)
+ }
+
+ gotIPs := map[string]struct{}{}
+ for _, ip := range ips {
+ gotIPs[ip.String()] = struct{}{}
+ }
+ wantIPs := map[string]struct{}{}
+ if wantErr == nil {
+ for _, ip := range tt.wantIPs {
+ wantIPs[ip] = struct{}{}
+ }
+ }
+ if !maps.Equal(gotIPs, wantIPs) {
+ t.Errorf("#%d (%s) strict=%v: got ips %v; want %v", i, tt.desc, strict, gotIPs, wantIPs)
+ }
+ }
+ }
+}
+
+// Issue 17448. With StrictErrors enabled, temporary errors should make
+// LookupTXT stop walking the search list.
+func TestStrictErrorsLookupTXT(t *testing.T) {
+ defer dnsWaitGroup.Wait()
+
+ conf, err := newResolvConfTest()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer conf.teardown()
+
+ confData := []string{
+ "nameserver 192.0.2.53",
+ "search x.golang.org y.golang.org",
+ }
+ if err := conf.writeAndUpdate(confData); err != nil {
+ t.Fatal(err)
+ }
+
+ const name = "test"
+ const server = "192.0.2.53:53"
+ const searchX = "test.x.golang.org."
+ const searchY = "test.y.golang.org."
+ const txt = "Hello World"
+
+ fake := fakeDNSServer{rh: func(_, s string, q dnsmessage.Message, deadline time.Time) (dnsmessage.Message, error) {
+ t.Log(s, q)
+
+ switch q.Questions[0].Name.String() {
+ case searchX:
+ return dnsmessage.Message{}, os.ErrDeadlineExceeded
+ case searchY:
+ return mockTXTResponse(q), nil
+ default:
+ return dnsmessage.Message{}, fmt.Errorf("Unexpected Name: %v", q.Questions[0].Name)
+ }
+ }}
+
+ for _, strict := range []bool{true, false} {
+ r := Resolver{StrictErrors: strict, Dial: fake.DialContext}
+ p, _, err := r.lookup(context.Background(), name, dnsmessage.TypeTXT, nil)
+ var wantErr error
+ var wantRRs int
+ if strict {
+ wantErr = &DNSError{
+ Err: os.ErrDeadlineExceeded.Error(),
+ Name: name,
+ Server: server,
+ IsTimeout: true,
+ IsTemporary: true,
+ }
+ } else {
+ wantRRs = 1
+ }
+ if !reflect.DeepEqual(err, wantErr) {
+ t.Errorf("strict=%v: got err %#v; want %#v", strict, err, wantErr)
+ }
+ a, err := p.AllAnswers()
+ if err != nil {
+ a = nil
+ }
+ if len(a) != wantRRs {
+ t.Errorf("strict=%v: got %v; want %v", strict, len(a), wantRRs)
+ }
+ }
+}
+
+// Test for a race between uninstalling the test hooks and closing a
+// socket connection. This used to fail when testing with -race.
+func TestDNSGoroutineRace(t *testing.T) {
+ defer dnsWaitGroup.Wait()
+
+ fake := fakeDNSServer{rh: func(n, s string, q dnsmessage.Message, t time.Time) (dnsmessage.Message, error) {
+ time.Sleep(10 * time.Microsecond)
+ return dnsmessage.Message{}, os.ErrDeadlineExceeded
+ }}
+ r := Resolver{PreferGo: true, Dial: fake.DialContext}
+
+ // The timeout here is less than the timeout used by the server,
+ // so the goroutine started to query the (fake) server will hang
+ // around after this test is done if we don't call dnsWaitGroup.Wait.
+ ctx, cancel := context.WithTimeout(context.Background(), 2*time.Microsecond)
+ defer cancel()
+ _, err := r.LookupIPAddr(ctx, "where.are.they.now")
+ if err == nil {
+ t.Fatal("fake DNS lookup unexpectedly succeeded")
+ }
+}
+
+func lookupWithFake(fake fakeDNSServer, name string, typ dnsmessage.Type) error {
+ r := Resolver{PreferGo: true, Dial: fake.DialContext}
+
+ conf := getSystemDNSConfig()
+
+ ctx, cancel := context.WithCancel(context.Background())
+ defer cancel()
+
+ _, _, err := r.tryOneName(ctx, conf, name, typ)
+ return err
+}
+
+// Issue 8434: verify that Temporary returns true on an error when rcode
+// is SERVFAIL
+func TestIssue8434(t *testing.T) {
+ err := lookupWithFake(fakeDNSServer{
+ rh: func(n, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ return dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.ID,
+ Response: true,
+ RCode: dnsmessage.RCodeServerFailure,
+ },
+ Questions: q.Questions,
+ }, nil
+ },
+ }, "golang.org.", dnsmessage.TypeALL)
+ if err == nil {
+ t.Fatal("expected an error")
+ }
+ if ne, ok := err.(Error); !ok {
+ t.Fatalf("err = %#v; wanted something supporting net.Error", err)
+ } else if !ne.Temporary() {
+ t.Fatalf("Temporary = false for err = %#v; want Temporary == true", err)
+ }
+ if de, ok := err.(*DNSError); !ok {
+ t.Fatalf("err = %#v; wanted a *net.DNSError", err)
+ } else if !de.IsTemporary {
+ t.Fatalf("IsTemporary = false for err = %#v; want IsTemporary == true", err)
+ }
+}
+
+func TestIssueNoSuchHostExists(t *testing.T) {
+ err := lookupWithFake(fakeDNSServer{
+ rh: func(n, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ return dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.ID,
+ Response: true,
+ RCode: dnsmessage.RCodeNameError,
+ },
+ Questions: q.Questions,
+ }, nil
+ },
+ }, "golang.org.", dnsmessage.TypeALL)
+ if err == nil {
+ t.Fatal("expected an error")
+ }
+ if _, ok := err.(Error); !ok {
+ t.Fatalf("err = %#v; wanted something supporting net.Error", err)
+ }
+ if de, ok := err.(*DNSError); !ok {
+ t.Fatalf("err = %#v; wanted a *net.DNSError", err)
+ } else if !de.IsNotFound {
+ t.Fatalf("IsNotFound = false for err = %#v; want IsNotFound == true", err)
+ }
+}
+
+// TestNoSuchHost verifies that tryOneName works correctly when the domain does
+// not exist.
+//
+// Issue 12778: verify that NXDOMAIN without RA bit errors as "no such host"
+// and not "server misbehaving"
+//
+// Issue 25336: verify that NXDOMAIN errors fail fast.
+//
+// Issue 27525: verify that empty answers fail fast.
+func TestNoSuchHost(t *testing.T) {
+ tests := []struct {
+ name string
+ f func(string, string, dnsmessage.Message, time.Time) (dnsmessage.Message, error)
+ }{
+ {
+ "NXDOMAIN",
+ func(n, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ return dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.ID,
+ Response: true,
+ RCode: dnsmessage.RCodeNameError,
+ RecursionAvailable: false,
+ },
+ Questions: q.Questions,
+ }, nil
+ },
+ },
+ {
+ "no answers",
+ func(n, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ return dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.ID,
+ Response: true,
+ RCode: dnsmessage.RCodeSuccess,
+ RecursionAvailable: false,
+ Authoritative: true,
+ },
+ Questions: q.Questions,
+ }, nil
+ },
+ },
+ }
+
+ for _, test := range tests {
+ t.Run(test.name, func(t *testing.T) {
+ lookups := 0
+ err := lookupWithFake(fakeDNSServer{
+ rh: func(n, s string, q dnsmessage.Message, d time.Time) (dnsmessage.Message, error) {
+ lookups++
+ return test.f(n, s, q, d)
+ },
+ }, ".", dnsmessage.TypeALL)
+
+ if lookups != 1 {
+ t.Errorf("got %d lookups, wanted 1", lookups)
+ }
+
+ if err == nil {
+ t.Fatal("expected an error")
+ }
+ de, ok := err.(*DNSError)
+ if !ok {
+ t.Fatalf("err = %#v; wanted a *net.DNSError", err)
+ }
+ if de.Err != errNoSuchHost.Error() {
+ t.Fatalf("Err = %#v; wanted %q", de.Err, errNoSuchHost.Error())
+ }
+ if !de.IsNotFound {
+ t.Fatalf("IsNotFound = %v wanted true", de.IsNotFound)
+ }
+ })
+ }
+}
+
+// Issue 26573: verify that Conns that don't implement PacketConn are treated
+// as streams even when udp was requested.
+func TestDNSDialTCP(t *testing.T) {
+ fake := fakeDNSServer{
+ rh: func(n, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ r := dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.Header.ID,
+ Response: true,
+ RCode: dnsmessage.RCodeSuccess,
+ },
+ Questions: q.Questions,
+ }
+ return r, nil
+ },
+ alwaysTCP: true,
+ }
+ r := Resolver{PreferGo: true, Dial: fake.DialContext}
+ ctx := context.Background()
+ _, _, err := r.exchange(ctx, "0.0.0.0", mustQuestion("com.", dnsmessage.TypeALL, dnsmessage.ClassINET), time.Second, useUDPOrTCP, false)
+ if err != nil {
+ t.Fatal("exchange failed:", err)
+ }
+}
+
+// Issue 27763: verify that two strings in one TXT record are concatenated.
+func TestTXTRecordTwoStrings(t *testing.T) {
+ fake := fakeDNSServer{
+ rh: func(n, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ r := dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.Header.ID,
+ Response: true,
+ RCode: dnsmessage.RCodeSuccess,
+ },
+ Questions: q.Questions,
+ Answers: []dnsmessage.Resource{
+ {
+ Header: dnsmessage.ResourceHeader{
+ Name: q.Questions[0].Name,
+ Type: dnsmessage.TypeA,
+ Class: dnsmessage.ClassINET,
+ },
+ Body: &dnsmessage.TXTResource{
+ TXT: []string{"string1 ", "string2"},
+ },
+ },
+ {
+ Header: dnsmessage.ResourceHeader{
+ Name: q.Questions[0].Name,
+ Type: dnsmessage.TypeA,
+ Class: dnsmessage.ClassINET,
+ },
+ Body: &dnsmessage.TXTResource{
+ TXT: []string{"onestring"},
+ },
+ },
+ },
+ }
+ return r, nil
+ },
+ }
+ r := Resolver{PreferGo: true, Dial: fake.DialContext}
+ txt, err := r.lookupTXT(context.Background(), "golang.org")
+ if err != nil {
+ t.Fatal("LookupTXT failed:", err)
+ }
+ if want := 2; len(txt) != want {
+ t.Fatalf("len(txt), got %d, want %d", len(txt), want)
+ }
+ if want := "string1 string2"; txt[0] != want {
+ t.Errorf("txt[0], got %q, want %q", txt[0], want)
+ }
+ if want := "onestring"; txt[1] != want {
+ t.Errorf("txt[1], got %q, want %q", txt[1], want)
+ }
+}
+
+// Issue 29644: support single-request resolv.conf option in pure Go resolver.
+// The A and AAAA queries will be sent sequentially, not in parallel.
+func TestSingleRequestLookup(t *testing.T) {
+ defer dnsWaitGroup.Wait()
+ var (
+ firstcalled int32
+ ipv4 int32 = 1
+ ipv6 int32 = 2
+ )
+ fake := fakeDNSServer{rh: func(n, s string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ r := dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.ID,
+ Response: true,
+ },
+ Questions: q.Questions,
+ }
+ for _, question := range q.Questions {
+ switch question.Type {
+ case dnsmessage.TypeA:
+ if question.Name.String() == "slowipv4.example.net." {
+ time.Sleep(10 * time.Millisecond)
+ }
+ if !atomic.CompareAndSwapInt32(&firstcalled, 0, ipv4) {
+ t.Errorf("the A query was received after the AAAA query !")
+ }
+ r.Answers = append(r.Answers, dnsmessage.Resource{
+ Header: dnsmessage.ResourceHeader{
+ Name: q.Questions[0].Name,
+ Type: dnsmessage.TypeA,
+ Class: dnsmessage.ClassINET,
+ Length: 4,
+ },
+ Body: &dnsmessage.AResource{
+ A: TestAddr,
+ },
+ })
+ case dnsmessage.TypeAAAA:
+ atomic.CompareAndSwapInt32(&firstcalled, 0, ipv6)
+ r.Answers = append(r.Answers, dnsmessage.Resource{
+ Header: dnsmessage.ResourceHeader{
+ Name: q.Questions[0].Name,
+ Type: dnsmessage.TypeAAAA,
+ Class: dnsmessage.ClassINET,
+ Length: 16,
+ },
+ Body: &dnsmessage.AAAAResource{
+ AAAA: TestAddr6,
+ },
+ })
+ }
+ }
+ return r, nil
+ }}
+ r := Resolver{PreferGo: true, Dial: fake.DialContext}
+
+ conf, err := newResolvConfTest()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer conf.teardown()
+ if err := conf.writeAndUpdate([]string{"options single-request"}); err != nil {
+ t.Fatal(err)
+ }
+ for _, name := range []string{"hostname.example.net", "slowipv4.example.net"} {
+ firstcalled = 0
+ _, err := r.LookupIPAddr(context.Background(), name)
+ if err != nil {
+ t.Error(err)
+ }
+ }
+}
+
+// Issue 29358. Add configuration knob to force TCP-only DNS requests in the pure Go resolver.
+func TestDNSUseTCP(t *testing.T) {
+ fake := fakeDNSServer{
+ rh: func(n, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ r := dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.Header.ID,
+ Response: true,
+ RCode: dnsmessage.RCodeSuccess,
+ },
+ Questions: q.Questions,
+ }
+ if n == "udp" {
+ t.Fatal("udp protocol was used instead of tcp")
+ }
+ return r, nil
+ },
+ }
+ r := Resolver{PreferGo: true, Dial: fake.DialContext}
+ ctx, cancel := context.WithCancel(context.Background())
+ defer cancel()
+ _, _, err := r.exchange(ctx, "0.0.0.0", mustQuestion("com.", dnsmessage.TypeALL, dnsmessage.ClassINET), time.Second, useTCPOnly, false)
+ if err != nil {
+ t.Fatal("exchange failed:", err)
+ }
+}
+
+func TestDNSUseTCPTruncated(t *testing.T) {
+ fake := fakeDNSServer{
+ rh: func(n, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ r := dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.Header.ID,
+ Response: true,
+ RCode: dnsmessage.RCodeSuccess,
+ Truncated: true,
+ },
+ Questions: q.Questions,
+ Answers: []dnsmessage.Resource{
+ {
+ Header: dnsmessage.ResourceHeader{
+ Name: q.Questions[0].Name,
+ Type: dnsmessage.TypeA,
+ Class: dnsmessage.ClassINET,
+ Length: 4,
+ },
+ Body: &dnsmessage.AResource{
+ A: TestAddr,
+ },
+ },
+ },
+ }
+ if n == "udp" {
+ t.Fatal("udp protocol was used instead of tcp")
+ }
+ return r, nil
+ },
+ }
+ r := Resolver{PreferGo: true, Dial: fake.DialContext}
+ ctx, cancel := context.WithCancel(context.Background())
+ defer cancel()
+ p, _, err := r.exchange(ctx, "0.0.0.0", mustQuestion("com.", dnsmessage.TypeALL, dnsmessage.ClassINET), time.Second, useTCPOnly, false)
+ if err != nil {
+ t.Fatal("exchange failed:", err)
+ }
+ a, err := p.AllAnswers()
+ if err != nil {
+ t.Fatalf("unexpected error %v getting all answers", err)
+ }
+ if len(a) != 1 {
+ t.Fatalf("got %d answers; want 1", len(a))
+ }
+}
+
+// Issue 34660: PTR response with non-PTR answers should ignore non-PTR
+func TestPTRandNonPTR(t *testing.T) {
+ fake := fakeDNSServer{
+ rh: func(n, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ r := dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.Header.ID,
+ Response: true,
+ RCode: dnsmessage.RCodeSuccess,
+ },
+ Questions: q.Questions,
+ Answers: []dnsmessage.Resource{
+ {
+ Header: dnsmessage.ResourceHeader{
+ Name: q.Questions[0].Name,
+ Type: dnsmessage.TypePTR,
+ Class: dnsmessage.ClassINET,
+ },
+ Body: &dnsmessage.PTRResource{
+ PTR: dnsmessage.MustNewName("golang.org."),
+ },
+ },
+ {
+ Header: dnsmessage.ResourceHeader{
+ Name: q.Questions[0].Name,
+ Type: dnsmessage.TypeTXT,
+ Class: dnsmessage.ClassINET,
+ },
+ Body: &dnsmessage.TXTResource{
+ TXT: []string{"PTR 8 6 60 ..."}, // fake RRSIG
+ },
+ },
+ },
+ }
+ return r, nil
+ },
+ }
+ r := Resolver{PreferGo: true, Dial: fake.DialContext}
+ names, err := r.lookupAddr(context.Background(), "192.0.2.123")
+ if err != nil {
+ t.Fatalf("LookupAddr: %v", err)
+ }
+ if want := []string{"golang.org."}; !slices.Equal(names, want) {
+ t.Errorf("names = %q; want %q", names, want)
+ }
+}
+
+func TestCVE202133195(t *testing.T) {
+ fake := fakeDNSServer{
+ rh: func(n, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ r := dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.Header.ID,
+ Response: true,
+ RCode: dnsmessage.RCodeSuccess,
+ RecursionAvailable: true,
+ },
+ Questions: q.Questions,
+ }
+ switch q.Questions[0].Type {
+ case dnsmessage.TypeCNAME:
+ r.Answers = []dnsmessage.Resource{}
+ case dnsmessage.TypeA: // CNAME lookup uses a A/AAAA as a proxy
+ r.Answers = append(r.Answers,
+ dnsmessage.Resource{
+ Header: dnsmessage.ResourceHeader{
+ Name: dnsmessage.MustNewName(".golang.org."),
+ Type: dnsmessage.TypeA,
+ Class: dnsmessage.ClassINET,
+ Length: 4,
+ },
+ Body: &dnsmessage.AResource{
+ A: TestAddr,
+ },
+ },
+ )
+ case dnsmessage.TypeSRV:
+ n := q.Questions[0].Name
+ if n.String() == "_hdr._tcp.golang.org." {
+ n = dnsmessage.MustNewName(".golang.org.")
+ }
+ r.Answers = append(r.Answers,
+ dnsmessage.Resource{
+ Header: dnsmessage.ResourceHeader{
+ Name: n,
+ Type: dnsmessage.TypeSRV,
+ Class: dnsmessage.ClassINET,
+ Length: 4,
+ },
+ Body: &dnsmessage.SRVResource{
+ Target: dnsmessage.MustNewName(".golang.org."),
+ },
+ },
+ dnsmessage.Resource{
+ Header: dnsmessage.ResourceHeader{
+ Name: n,
+ Type: dnsmessage.TypeSRV,
+ Class: dnsmessage.ClassINET,
+ Length: 4,
+ },
+ Body: &dnsmessage.SRVResource{
+ Target: dnsmessage.MustNewName("good.golang.org."),
+ },
+ },
+ )
+ case dnsmessage.TypeMX:
+ r.Answers = append(r.Answers,
+ dnsmessage.Resource{
+ Header: dnsmessage.ResourceHeader{
+ Name: dnsmessage.MustNewName(".golang.org."),
+ Type: dnsmessage.TypeMX,
+ Class: dnsmessage.ClassINET,
+ Length: 4,
+ },
+ Body: &dnsmessage.MXResource{
+ MX: dnsmessage.MustNewName(".golang.org."),
+ },
+ },
+ dnsmessage.Resource{
+ Header: dnsmessage.ResourceHeader{
+ Name: dnsmessage.MustNewName("good.golang.org."),
+ Type: dnsmessage.TypeMX,
+ Class: dnsmessage.ClassINET,
+ Length: 4,
+ },
+ Body: &dnsmessage.MXResource{
+ MX: dnsmessage.MustNewName("good.golang.org."),
+ },
+ },
+ dnsmessage.Resource{
+ Header: dnsmessage.ResourceHeader{
+ Name: dnsmessage.MustNewName("127.0.0.1."),
+ Type: dnsmessage.TypeMX,
+ Class: dnsmessage.ClassINET,
+ Length: 4,
+ },
+ Body: &dnsmessage.MXResource{
+ MX: dnsmessage.MustNewName("127.0.0.1."),
+ },
+ },
+ dnsmessage.Resource{
+ Header: dnsmessage.ResourceHeader{
+ Name: dnsmessage.MustNewName("1.2.3.4.5."),
+ Type: dnsmessage.TypeMX,
+ Class: dnsmessage.ClassINET,
+ Length: 4,
+ },
+ Body: &dnsmessage.MXResource{
+ MX: dnsmessage.MustNewName("1.2.3.4.5."),
+ },
+ },
+ dnsmessage.Resource{
+ Header: dnsmessage.ResourceHeader{
+ Name: dnsmessage.MustNewName("2001:4860:0:2001::68."),
+ Type: dnsmessage.TypeMX,
+ Class: dnsmessage.ClassINET,
+ Length: 4,
+ },
+ Body: &dnsmessage.MXResource{
+ MX: dnsmessage.MustNewName("2001:4860:0:2001::68."),
+ },
+ },
+ dnsmessage.Resource{
+ Header: dnsmessage.ResourceHeader{
+ Name: dnsmessage.MustNewName("2001:4860:0:2001::68%zone."),
+ Type: dnsmessage.TypeMX,
+ Class: dnsmessage.ClassINET,
+ Length: 4,
+ },
+ Body: &dnsmessage.MXResource{
+ MX: dnsmessage.MustNewName("2001:4860:0:2001::68%zone."),
+ },
+ },
+ )
+ case dnsmessage.TypeNS:
+ r.Answers = append(r.Answers,
+ dnsmessage.Resource{
+ Header: dnsmessage.ResourceHeader{
+ Name: dnsmessage.MustNewName(".golang.org."),
+ Type: dnsmessage.TypeNS,
+ Class: dnsmessage.ClassINET,
+ Length: 4,
+ },
+ Body: &dnsmessage.NSResource{
+ NS: dnsmessage.MustNewName(".golang.org."),
+ },
+ },
+ dnsmessage.Resource{
+ Header: dnsmessage.ResourceHeader{
+ Name: dnsmessage.MustNewName("good.golang.org."),
+ Type: dnsmessage.TypeNS,
+ Class: dnsmessage.ClassINET,
+ Length: 4,
+ },
+ Body: &dnsmessage.NSResource{
+ NS: dnsmessage.MustNewName("good.golang.org."),
+ },
+ },
+ )
+ case dnsmessage.TypePTR:
+ r.Answers = append(r.Answers,
+ dnsmessage.Resource{
+ Header: dnsmessage.ResourceHeader{
+ Name: dnsmessage.MustNewName(".golang.org."),
+ Type: dnsmessage.TypePTR,
+ Class: dnsmessage.ClassINET,
+ Length: 4,
+ },
+ Body: &dnsmessage.PTRResource{
+ PTR: dnsmessage.MustNewName(".golang.org."),
+ },
+ },
+ dnsmessage.Resource{
+ Header: dnsmessage.ResourceHeader{
+ Name: dnsmessage.MustNewName("good.golang.org."),
+ Type: dnsmessage.TypePTR,
+ Class: dnsmessage.ClassINET,
+ Length: 4,
+ },
+ Body: &dnsmessage.PTRResource{
+ PTR: dnsmessage.MustNewName("good.golang.org."),
+ },
+ },
+ )
+ }
+ return r, nil
+ },
+ }
+
+ r := Resolver{PreferGo: true, Dial: fake.DialContext}
+ // Change the default resolver to match our manipulated resolver
+ originalDefault := DefaultResolver
+ DefaultResolver = &r
+ defer func() { DefaultResolver = originalDefault }()
+ // Redirect host file lookups.
+ defer func(orig string) { hostsFilePath = orig }(hostsFilePath)
+ hostsFilePath = "testdata/hosts"
+
+ tests := []struct {
+ name string
+ f func(*testing.T)
+ }{
+ {
+ name: "CNAME",
+ f: func(t *testing.T) {
+ expectedErr := &DNSError{Err: errMalformedDNSRecordsDetail, Name: "golang.org"}
+ _, err := r.LookupCNAME(context.Background(), "golang.org")
+ if err.Error() != expectedErr.Error() {
+ t.Fatalf("unexpected error: %s", err)
+ }
+ _, err = LookupCNAME("golang.org")
+ if err.Error() != expectedErr.Error() {
+ t.Fatalf("unexpected error: %s", err)
+ }
+ },
+ },
+ {
+ name: "SRV (bad record)",
+ f: func(t *testing.T) {
+ expected := []*SRV{
+ {
+ Target: "good.golang.org.",
+ },
+ }
+ expectedErr := &DNSError{Err: errMalformedDNSRecordsDetail, Name: "golang.org"}
+ _, records, err := r.LookupSRV(context.Background(), "target", "tcp", "golang.org")
+ if err.Error() != expectedErr.Error() {
+ t.Fatalf("unexpected error: %s", err)
+ }
+ if !reflect.DeepEqual(records, expected) {
+ t.Error("Unexpected record set")
+ }
+ _, records, err = LookupSRV("target", "tcp", "golang.org")
+ if err.Error() != expectedErr.Error() {
+ t.Errorf("unexpected error: %s", err)
+ }
+ if !reflect.DeepEqual(records, expected) {
+ t.Error("Unexpected record set")
+ }
+ },
+ },
+ {
+ name: "SRV (bad header)",
+ f: func(t *testing.T) {
+ _, _, err := r.LookupSRV(context.Background(), "hdr", "tcp", "golang.org.")
+ if expected := "lookup golang.org.: SRV header name is invalid"; err == nil || err.Error() != expected {
+ t.Errorf("Resolver.LookupSRV returned unexpected error, got %q, want %q", err, expected)
+ }
+ _, _, err = LookupSRV("hdr", "tcp", "golang.org.")
+ if expected := "lookup golang.org.: SRV header name is invalid"; err == nil || err.Error() != expected {
+ t.Errorf("LookupSRV returned unexpected error, got %q, want %q", err, expected)
+ }
+ },
+ },
+ {
+ name: "MX",
+ f: func(t *testing.T) {
+ expected := []string{
+ "127.0.0.1.",
+ "2001:4860:0:2001::68.",
+ "good.golang.org.",
+ }
+ expectedErr := &DNSError{Err: errMalformedDNSRecordsDetail, Name: "golang.org"}
+ records, err := r.LookupMX(context.Background(), "golang.org")
+ if err.Error() != expectedErr.Error() {
+ t.Fatalf("unexpected error: %s", err)
+ }
+
+ hosts := func(records []*MX) []string {
+ var got []string
+ for _, mx := range records {
+ got = append(got, mx.Host)
+ }
+ slices.Sort(got)
+ return got
+ }
+
+ got := hosts(records)
+ if !slices.Equal(got, expected) {
+ t.Errorf("Unexpected record set: got %v, want %v", got, expected)
+ }
+ records, err = LookupMX("golang.org")
+ if err.Error() != expectedErr.Error() {
+ t.Fatalf("unexpected error: %s", err)
+ }
+ got = hosts(records)
+ if !slices.Equal(got, expected) {
+ t.Errorf("Unexpected record set: got %v, want %v", got, expected)
+ }
+ },
+ },
+ {
+ name: "NS",
+ f: func(t *testing.T) {
+ expected := []*NS{
+ {
+ Host: "good.golang.org.",
+ },
+ }
+ expectedErr := &DNSError{Err: errMalformedDNSRecordsDetail, Name: "golang.org"}
+ records, err := r.LookupNS(context.Background(), "golang.org")
+ if err.Error() != expectedErr.Error() {
+ t.Fatalf("unexpected error: %s", err)
+ }
+ if !reflect.DeepEqual(records, expected) {
+ t.Error("Unexpected record set")
+ }
+ records, err = LookupNS("golang.org")
+ if err.Error() != expectedErr.Error() {
+ t.Fatalf("unexpected error: %s", err)
+ }
+ if !reflect.DeepEqual(records, expected) {
+ t.Error("Unexpected record set")
+ }
+ },
+ },
+ {
+ name: "Addr",
+ f: func(t *testing.T) {
+ expected := []string{"good.golang.org."}
+ expectedErr := &DNSError{Err: errMalformedDNSRecordsDetail, Name: "192.0.2.42"}
+ records, err := r.LookupAddr(context.Background(), "192.0.2.42")
+ if err.Error() != expectedErr.Error() {
+ t.Fatalf("unexpected error: %s", err)
+ }
+ if !slices.Equal(records, expected) {
+ t.Error("Unexpected record set")
+ }
+ records, err = LookupAddr("192.0.2.42")
+ if err.Error() != expectedErr.Error() {
+ t.Fatalf("unexpected error: %s", err)
+ }
+ if !slices.Equal(records, expected) {
+ t.Error("Unexpected record set")
+ }
+ },
+ },
+ }
+
+ for _, tc := range tests {
+ t.Run(tc.name, tc.f)
+ }
+
+}
+
+func TestNullMX(t *testing.T) {
+ fake := fakeDNSServer{
+ rh: func(n, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ r := dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.Header.ID,
+ Response: true,
+ RCode: dnsmessage.RCodeSuccess,
+ },
+ Questions: q.Questions,
+ Answers: []dnsmessage.Resource{
+ {
+ Header: dnsmessage.ResourceHeader{
+ Name: q.Questions[0].Name,
+ Type: dnsmessage.TypeMX,
+ Class: dnsmessage.ClassINET,
+ },
+ Body: &dnsmessage.MXResource{
+ MX: dnsmessage.MustNewName("."),
+ },
+ },
+ },
+ }
+ return r, nil
+ },
+ }
+ r := Resolver{PreferGo: true, Dial: fake.DialContext}
+ rrset, err := r.LookupMX(context.Background(), "golang.org")
+ if err != nil {
+ t.Fatalf("LookupMX: %v", err)
+ }
+ if want := []*MX{&MX{Host: "."}}; !reflect.DeepEqual(rrset, want) {
+ records := []string{}
+ for _, rr := range rrset {
+ records = append(records, fmt.Sprintf("%v", rr))
+ }
+ t.Errorf("records = [%v]; want [%v]", strings.Join(records, " "), want[0])
+ }
+}
+
+func TestRootNS(t *testing.T) {
+ // See https://golang.org/issue/45715.
+ fake := fakeDNSServer{
+ rh: func(n, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ r := dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.Header.ID,
+ Response: true,
+ RCode: dnsmessage.RCodeSuccess,
+ },
+ Questions: q.Questions,
+ Answers: []dnsmessage.Resource{
+ {
+ Header: dnsmessage.ResourceHeader{
+ Name: q.Questions[0].Name,
+ Type: dnsmessage.TypeNS,
+ Class: dnsmessage.ClassINET,
+ },
+ Body: &dnsmessage.NSResource{
+ NS: dnsmessage.MustNewName("i.root-servers.net."),
+ },
+ },
+ },
+ }
+ return r, nil
+ },
+ }
+ r := Resolver{PreferGo: true, Dial: fake.DialContext}
+ rrset, err := r.LookupNS(context.Background(), ".")
+ if err != nil {
+ t.Fatalf("LookupNS: %v", err)
+ }
+ if want := []*NS{&NS{Host: "i.root-servers.net."}}; !reflect.DeepEqual(rrset, want) {
+ records := []string{}
+ for _, rr := range rrset {
+ records = append(records, fmt.Sprintf("%v", rr))
+ }
+ t.Errorf("records = [%v]; want [%v]", strings.Join(records, " "), want[0])
+ }
+}
+
+func TestGoLookupIPCNAMEOrderHostsAliasesFilesOnlyMode(t *testing.T) {
+ defer func(orig string) { hostsFilePath = orig }(hostsFilePath)
+ hostsFilePath = "testdata/aliases"
+ mode := hostLookupFiles
+
+ for _, v := range lookupStaticHostAliasesTest {
+ testGoLookupIPCNAMEOrderHostsAliases(t, mode, v.lookup, absDomainName(v.res))
+ }
+}
+
+func TestGoLookupIPCNAMEOrderHostsAliasesFilesDNSMode(t *testing.T) {
+ defer func(orig string) { hostsFilePath = orig }(hostsFilePath)
+ hostsFilePath = "testdata/aliases"
+ mode := hostLookupFilesDNS
+
+ for _, v := range lookupStaticHostAliasesTest {
+ testGoLookupIPCNAMEOrderHostsAliases(t, mode, v.lookup, absDomainName(v.res))
+ }
+}
+
+var goLookupIPCNAMEOrderDNSFilesModeTests = []struct {
+ lookup, res string
+}{
+ // 127.0.1.1
+ {"invalid.invalid", "invalid.test"},
+}
+
+func TestGoLookupIPCNAMEOrderHostsAliasesDNSFilesMode(t *testing.T) {
+ defer func(orig string) { hostsFilePath = orig }(hostsFilePath)
+ hostsFilePath = "testdata/aliases"
+ mode := hostLookupDNSFiles
+
+ for _, v := range goLookupIPCNAMEOrderDNSFilesModeTests {
+ testGoLookupIPCNAMEOrderHostsAliases(t, mode, v.lookup, absDomainName(v.res))
+ }
+}
+
+func testGoLookupIPCNAMEOrderHostsAliases(t *testing.T, mode hostLookupOrder, lookup, lookupRes string) {
+ fake := fakeDNSServer{
+ rh: func(_, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ var answers []dnsmessage.Resource
+
+ if mode != hostLookupDNSFiles {
+ t.Fatal("received unexpected DNS query")
+ }
+
+ return dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.Header.ID,
+ Response: true,
+ },
+ Questions: []dnsmessage.Question{q.Questions[0]},
+ Answers: answers,
+ }, nil
+ },
+ }
+
+ r := Resolver{PreferGo: true, Dial: fake.DialContext}
+ ins := []string{lookup, absDomainName(lookup), strings.ToLower(lookup), strings.ToUpper(lookup)}
+ for _, in := range ins {
+ _, res, err := r.goLookupIPCNAMEOrder(context.Background(), "ip", in, mode, nil)
+ if err != nil {
+ t.Errorf("expected err == nil, but got error: %v", err)
+ }
+ if res.String() != lookupRes {
+ t.Errorf("goLookupIPCNAMEOrder(%v): got %v, want %v", in, res, lookupRes)
+ }
+ }
+}
+
+// Test that we advertise support for a larger DNS packet size.
+// This isn't a great test as it just tests the dnsmessage package
+// against itself.
+func TestDNSPacketSize(t *testing.T) {
+ t.Run("enabled", func(t *testing.T) {
+ testDNSPacketSize(t, false)
+ })
+ t.Run("disabled", func(t *testing.T) {
+ testDNSPacketSize(t, true)
+ })
+}
+
+func testDNSPacketSize(t *testing.T, disable bool) {
+ fake := fakeDNSServer{
+ rh: func(_, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ if disable {
+ if len(q.Additionals) > 0 {
+ t.Error("unexpected additional record")
+ }
+ } else {
+ if len(q.Additionals) == 0 {
+ t.Error("missing EDNS record")
+ } else if opt, ok := q.Additionals[0].Body.(*dnsmessage.OPTResource); !ok {
+ t.Errorf("additional record type %T, expected OPTResource", q.Additionals[0])
+ } else if len(opt.Options) != 0 {
+ t.Errorf("found %d Options, expected none", len(opt.Options))
+ } else {
+ got := int(q.Additionals[0].Header.Class)
+ t.Logf("EDNS packet size == %d", got)
+ if got != maxDNSPacketSize {
+ t.Errorf("EDNS packet size == %d, want %d", got, maxDNSPacketSize)
+ }
+ }
+ }
+
+ // Hand back a dummy answer to verify that
+ // LookupIPAddr completes.
+ r := dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.Header.ID,
+ Response: true,
+ RCode: dnsmessage.RCodeSuccess,
+ },
+ Questions: q.Questions,
+ }
+ if q.Questions[0].Type == dnsmessage.TypeA {
+ r.Answers = []dnsmessage.Resource{
+ {
+ Header: dnsmessage.ResourceHeader{
+ Name: q.Questions[0].Name,
+ Type: dnsmessage.TypeA,
+ Class: dnsmessage.ClassINET,
+ Length: 4,
+ },
+ Body: &dnsmessage.AResource{
+ A: TestAddr,
+ },
+ },
+ }
+ }
+ return r, nil
+ },
+ }
+
+ if disable {
+ t.Setenv("GODEBUG", "netedns0=0")
+ }
+
+ r := &Resolver{PreferGo: true, Dial: fake.DialContext}
+ if _, err := r.LookupIPAddr(context.Background(), "go.dev"); err != nil {
+ t.Errorf("lookup failed: %v", err)
+ }
+}
+
+func TestLongDNSNames(t *testing.T) {
+ const longDNSsuffix = ".go.dev."
+ const longDNSsuffixNoEndingDot = ".go.dev"
+
+ var longDNSPrefix = strings.Repeat("verylongdomainlabel.", 20)
+
+ var longDNSNamesTests = []struct {
+ req string
+ fail bool
+ }{
+ {req: longDNSPrefix[:255-len(longDNSsuffix)] + longDNSsuffix, fail: true},
+ {req: longDNSPrefix[:254-len(longDNSsuffix)] + longDNSsuffix},
+ {req: longDNSPrefix[:253-len(longDNSsuffix)] + longDNSsuffix},
+
+ {req: longDNSPrefix[:253-len(longDNSsuffixNoEndingDot)] + longDNSsuffixNoEndingDot},
+ {req: longDNSPrefix[:254-len(longDNSsuffixNoEndingDot)] + longDNSsuffixNoEndingDot, fail: true},
+ }
+
+ fake := fakeDNSServer{
+ rh: func(_, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ r := dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.Header.ID,
+ Response: true,
+ RCode: dnsmessage.RCodeSuccess,
+ },
+ Questions: q.Questions,
+ Answers: []dnsmessage.Resource{
+ {
+ Header: dnsmessage.ResourceHeader{
+ Name: q.Questions[0].Name,
+ Type: q.Questions[0].Type,
+ Class: dnsmessage.ClassINET,
+ },
+ },
+ },
+ }
+
+ switch q.Questions[0].Type {
+ case dnsmessage.TypeA:
+ r.Answers[0].Body = &dnsmessage.AResource{A: TestAddr}
+ case dnsmessage.TypeAAAA:
+ r.Answers[0].Body = &dnsmessage.AAAAResource{AAAA: TestAddr6}
+ case dnsmessage.TypeTXT:
+ r.Answers[0].Body = &dnsmessage.TXTResource{TXT: []string{"."}}
+ case dnsmessage.TypeMX:
+ r.Answers[0].Body = &dnsmessage.MXResource{
+ MX: dnsmessage.MustNewName("go.dev."),
+ }
+ case dnsmessage.TypeNS:
+ r.Answers[0].Body = &dnsmessage.NSResource{
+ NS: dnsmessage.MustNewName("go.dev."),
+ }
+ case dnsmessage.TypeSRV:
+ r.Answers[0].Body = &dnsmessage.SRVResource{
+ Target: dnsmessage.MustNewName("go.dev."),
+ }
+ case dnsmessage.TypeCNAME:
+ r.Answers[0].Body = &dnsmessage.CNAMEResource{
+ CNAME: dnsmessage.MustNewName("fake.cname."),
+ }
+ default:
+ panic("unknown dnsmessage type")
+ }
+
+ return r, nil
+ },
+ }
+
+ r := &Resolver{PreferGo: true, Dial: fake.DialContext}
+
+ methodTests := []string{"CNAME", "Host", "IP", "IPAddr", "MX", "NS", "NetIP", "SRV", "TXT"}
+ query := func(t string, req string) error {
+ switch t {
+ case "CNAME":
+ _, err := r.LookupCNAME(context.Background(), req)
+ return err
+ case "Host":
+ _, err := r.LookupHost(context.Background(), req)
+ return err
+ case "IP":
+ _, err := r.LookupIP(context.Background(), "ip", req)
+ return err
+ case "IPAddr":
+ _, err := r.LookupIPAddr(context.Background(), req)
+ return err
+ case "MX":
+ _, err := r.LookupMX(context.Background(), req)
+ return err
+ case "NS":
+ _, err := r.LookupNS(context.Background(), req)
+ return err
+ case "NetIP":
+ _, err := r.LookupNetIP(context.Background(), "ip", req)
+ return err
+ case "SRV":
+ const service = "service"
+ const proto = "proto"
+ req = req[len(service)+len(proto)+4:]
+ _, _, err := r.LookupSRV(context.Background(), service, proto, req)
+ return err
+ case "TXT":
+ _, err := r.LookupTXT(context.Background(), req)
+ return err
+ }
+ panic("unknown query method")
+ }
+
+ for i, v := range longDNSNamesTests {
+ for _, testName := range methodTests {
+ err := query(testName, v.req)
+ if v.fail {
+ if err == nil {
+ t.Errorf("%v: Lookup%v: unexpected success", i, testName)
+ break
+ }
+
+ expectedErr := DNSError{Err: errNoSuchHost.Error(), Name: v.req, IsNotFound: true}
+ dnsErr, _ := errors.AsType[*DNSError](err)
+ if dnsErr == nil || *dnsErr != expectedErr {
+ t.Errorf("%v: Lookup%v: unexpected error: %v", i, testName, err)
+ }
+ break
+ }
+ if err != nil {
+ t.Errorf("%v: Lookup%v: unexpected error: %v", i, testName, err)
+ }
+ }
+ }
+}
+
+func TestDNSTrustAD(t *testing.T) {
+ fake := fakeDNSServer{
+ rh: func(_, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ if q.Questions[0].Name.String() == "notrustad.go.dev." && q.Header.AuthenticData {
+ t.Error("unexpected AD bit")
+ }
+
+ if q.Questions[0].Name.String() == "trustad.go.dev." && !q.Header.AuthenticData {
+ t.Error("expected AD bit")
+ }
+
+ r := dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.Header.ID,
+ Response: true,
+ RCode: dnsmessage.RCodeSuccess,
+ },
+ Questions: q.Questions,
+ }
+ if q.Questions[0].Type == dnsmessage.TypeA {
+ r.Answers = []dnsmessage.Resource{
+ {
+ Header: dnsmessage.ResourceHeader{
+ Name: q.Questions[0].Name,
+ Type: dnsmessage.TypeA,
+ Class: dnsmessage.ClassINET,
+ Length: 4,
+ },
+ Body: &dnsmessage.AResource{
+ A: TestAddr,
+ },
+ },
+ }
+ }
+
+ return r, nil
+ }}
+
+ r := &Resolver{PreferGo: true, Dial: fake.DialContext}
+
+ conf, err := newResolvConfTest()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer conf.teardown()
+
+ err = conf.writeAndUpdate([]string{"nameserver 127.0.0.1"})
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ if _, err := r.LookupIPAddr(context.Background(), "notrustad.go.dev"); err != nil {
+ t.Errorf("lookup failed: %v", err)
+ }
+
+ err = conf.writeAndUpdate([]string{"nameserver 127.0.0.1", "options trust-ad"})
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ if _, err := r.LookupIPAddr(context.Background(), "trustad.go.dev"); err != nil {
+ t.Errorf("lookup failed: %v", err)
+ }
+}
+
+func TestDNSConfigNoReload(t *testing.T) {
+ r := &Resolver{PreferGo: true, Dial: func(ctx context.Context, network, address string) (Conn, error) {
+ if address != "192.0.2.1:53" {
+ return nil, errors.New("configuration unexpectedly changed")
+ }
+ return fakeDNSServerSuccessful.DialContext(ctx, network, address)
+ }}
+
+ conf, err := newResolvConfTest()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer conf.teardown()
+
+ err = conf.writeAndUpdateWithLastCheckedTime([]string{"nameserver 192.0.2.1", "options no-reload"}, time.Now().Add(-time.Hour))
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ if _, err = r.LookupHost(context.Background(), "go.dev"); err != nil {
+ t.Fatal(err)
+ }
+
+ err = conf.write([]string{"nameserver 192.0.2.200"})
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ if _, err = r.LookupHost(context.Background(), "go.dev"); err != nil {
+ t.Fatal(err)
+ }
+}
+
+func TestLookupOrderFilesNoSuchHost(t *testing.T) {
+ defer func(orig string) { hostsFilePath = orig }(hostsFilePath)
+ if runtime.GOOS != "openbsd" {
+ defer setSystemNSS(getSystemNSS(), 0)
+ setSystemNSS(nssStr(t, "hosts: files"), time.Hour)
+ }
+
+ conf, err := newResolvConfTest()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer conf.teardown()
+
+ resolvConf := dnsConfig{servers: defaultNS}
+ if runtime.GOOS == "openbsd" {
+ // Set error to ErrNotExist, so that the hostLookupOrder
+ // returns hostLookupFiles for openbsd.
+ resolvConf.err = os.ErrNotExist
+ }
+
+ if !conf.forceUpdateConf(&resolvConf, time.Now().Add(time.Hour)) {
+ t.Fatal("failed to update resolv config")
+ }
+
+ tmpFile := filepath.Join(t.TempDir(), "hosts")
+ if err := os.WriteFile(tmpFile, []byte{}, 0660); err != nil {
+ t.Fatal(err)
+ }
+ hostsFilePath = tmpFile
+
+ const testName = "test.invalid"
+
+ order, _ := systemConf().hostLookupOrder(DefaultResolver, testName)
+ if order != hostLookupFiles {
+ // skip test for systems which do not return hostLookupFiles
+ t.Skipf("hostLookupOrder did not return hostLookupFiles")
+ }
+
+ var lookupTests = []struct {
+ name string
+ lookup func(name string) error
+ }{
+ {
+ name: "Host",
+ lookup: func(name string) error {
+ _, err = DefaultResolver.LookupHost(context.Background(), name)
+ return err
+ },
+ },
+ {
+ name: "IP",
+ lookup: func(name string) error {
+ _, err = DefaultResolver.LookupIP(context.Background(), "ip", name)
+ return err
+ },
+ },
+ {
+ name: "IPAddr",
+ lookup: func(name string) error {
+ _, err = DefaultResolver.LookupIPAddr(context.Background(), name)
+ return err
+ },
+ },
+ {
+ name: "NetIP",
+ lookup: func(name string) error {
+ _, err = DefaultResolver.LookupNetIP(context.Background(), "ip", name)
+ return err
+ },
+ },
+ }
+
+ for _, v := range lookupTests {
+ err := v.lookup(testName)
+
+ if err == nil {
+ t.Errorf("Lookup%v: unexpected success", v.name)
+ continue
+ }
+
+ expectedErr := DNSError{Err: errNoSuchHost.Error(), Name: testName, IsNotFound: true}
+ dnsErr, _ := errors.AsType[*DNSError](err)
+ if dnsErr == nil || *dnsErr != expectedErr {
+ t.Errorf("Lookup%v: unexpected error: %v", v.name, err)
+ }
+ }
+}
+
+func TestExtendedRCode(t *testing.T) {
+ fake := fakeDNSServer{
+ rh: func(_, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) {
+ fraudSuccessCode := dnsmessage.RCodeSuccess | 1<<10
+
+ var edns0Hdr dnsmessage.ResourceHeader
+ edns0Hdr.SetEDNS0(maxDNSPacketSize, fraudSuccessCode, false)
+
+ return dnsmessage.Message{
+ Header: dnsmessage.Header{
+ ID: q.Header.ID,
+ Response: true,
+ RCode: fraudSuccessCode,
+ },
+ Questions: []dnsmessage.Question{q.Questions[0]},
+ Additionals: []dnsmessage.Resource{{
+ Header: edns0Hdr,
+ Body: &dnsmessage.OPTResource{},
+ }},
+ }, nil
+ },
+ }
+
+ r := &Resolver{PreferGo: true, Dial: fake.DialContext}
+ _, _, err := r.tryOneName(context.Background(), getSystemDNSConfig(), "go.dev.", dnsmessage.TypeA)
+ if dnsErr, ok := errors.AsType[*DNSError](err); !ok || dnsErr.Err != errServerMisbehaving.Error() {
+ t.Fatalf("r.tryOneName(): unexpected error: %v", err)
+ }
+}
diff --git a/go/src/net/dnsconfig.go b/go/src/net/dnsconfig.go
new file mode 100644
index 0000000000000000000000000000000000000000..5a156ea0e4b6a7c7c9e009fe60a6dd8d621cb74b
--- /dev/null
+++ b/go/src/net/dnsconfig.go
@@ -0,0 +1,57 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "os"
+ "sync/atomic"
+ "time"
+ _ "unsafe"
+)
+
+// defaultNS is the default name servers to use in the absence of DNS configuration.
+//
+// defaultNS should be an internal detail,
+// but widely used packages access it using linkname.
+// Notable members of the hall of shame include:
+// - github.com/pojntfx/hydrapp/hydrapp
+// - github.com/mtibben/androiddnsfix
+//
+// Do not remove or change the type signature.
+// See go.dev/issue/67401.
+//
+//go:linkname defaultNS
+var defaultNS = []string{"127.0.0.1:53", "[::1]:53"}
+
+var getHostname = os.Hostname // variable for testing
+
+type dnsConfig struct {
+ servers []string // server addresses (in host:port form) to use
+ search []string // rooted suffixes to append to local name
+ ndots int // number of dots in name to trigger absolute lookup
+ timeout time.Duration // wait before giving up on a query, including retries
+ attempts int // lost packets before giving up on server
+ rotate bool // round robin among servers
+ unknownOpt bool // anything unknown was encountered
+ lookup []string // OpenBSD top-level database "lookup" order
+ err error // any error that occurs during open of resolv.conf
+ mtime time.Time // time of resolv.conf modification
+ soffset uint32 // used by serverOffset
+ singleRequest bool // use sequential A and AAAA queries instead of parallel queries
+ useTCP bool // force usage of TCP for DNS resolutions
+ trustAD bool // add AD flag to queries
+ noReload bool // do not check for config file updates
+}
+
+// serverOffset returns an offset that can be used to determine
+// indices of servers in c.servers when making queries.
+// When the rotate option is enabled, this offset increases.
+// Otherwise it is always 0.
+func (c *dnsConfig) serverOffset() uint32 {
+ if c.rotate {
+ return atomic.AddUint32(&c.soffset, 1) - 1 // return 0 to start
+ }
+ return 0
+}
diff --git a/go/src/net/dnsconfig_unix.go b/go/src/net/dnsconfig_unix.go
new file mode 100644
index 0000000000000000000000000000000000000000..0fcf2c6cc38426c735f5ca0404c39218a5f8f1eb
--- /dev/null
+++ b/go/src/net/dnsconfig_unix.go
@@ -0,0 +1,164 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !windows
+
+// Read system DNS config from /etc/resolv.conf
+
+package net
+
+import (
+ "internal/bytealg"
+ "internal/stringslite"
+ "net/netip"
+ "time"
+)
+
+// See resolv.conf(5) on a Linux machine.
+func dnsReadConfig(filename string) *dnsConfig {
+ conf := &dnsConfig{
+ ndots: 1,
+ timeout: 5 * time.Second,
+ attempts: 2,
+ }
+ file, err := open(filename)
+ if err != nil {
+ conf.servers = defaultNS
+ conf.search = dnsDefaultSearch()
+ conf.err = err
+ return conf
+ }
+ defer file.close()
+ if fi, err := file.file.Stat(); err == nil {
+ conf.mtime = fi.ModTime()
+ } else {
+ conf.servers = defaultNS
+ conf.search = dnsDefaultSearch()
+ conf.err = err
+ return conf
+ }
+ for line, ok := file.readLine(); ok; line, ok = file.readLine() {
+ if len(line) > 0 && (line[0] == ';' || line[0] == '#') {
+ // comment.
+ continue
+ }
+ f := getFields(line)
+ if len(f) < 1 {
+ continue
+ }
+ switch f[0] {
+ case "nameserver": // add one name server
+ if len(f) > 1 && len(conf.servers) < 3 { // small, but the standard limit
+ // One more check: make sure server name is
+ // just an IP address. Otherwise we need DNS
+ // to look it up.
+ if _, err := netip.ParseAddr(f[1]); err == nil {
+ conf.servers = append(conf.servers, JoinHostPort(f[1], "53"))
+ }
+ }
+
+ case "domain": // set search path to just this domain
+ if len(f) > 1 {
+ conf.search = []string{ensureRooted(f[1])}
+ }
+
+ case "search": // set search path to given servers
+ conf.search = make([]string, 0, len(f)-1)
+ for i := 1; i < len(f); i++ {
+ name := ensureRooted(f[i])
+ if name == "." {
+ continue
+ }
+ conf.search = append(conf.search, name)
+ }
+
+ case "options": // magic options
+ for _, s := range f[1:] {
+ switch {
+ case stringslite.HasPrefix(s, "ndots:"):
+ n, _, _ := dtoi(s[6:])
+ if n < 0 {
+ n = 0
+ } else if n > 15 {
+ n = 15
+ }
+ conf.ndots = n
+ case stringslite.HasPrefix(s, "timeout:"):
+ n, _, _ := dtoi(s[8:])
+ if n < 1 {
+ n = 1
+ }
+ conf.timeout = time.Duration(n) * time.Second
+ case stringslite.HasPrefix(s, "attempts:"):
+ n, _, _ := dtoi(s[9:])
+ if n < 1 {
+ n = 1
+ }
+ conf.attempts = n
+ case s == "rotate":
+ conf.rotate = true
+ case s == "single-request" || s == "single-request-reopen":
+ // Linux option:
+ // http://man7.org/linux/man-pages/man5/resolv.conf.5.html
+ // "By default, glibc performs IPv4 and IPv6 lookups in parallel [...]
+ // This option disables the behavior and makes glibc
+ // perform the IPv6 and IPv4 requests sequentially."
+ conf.singleRequest = true
+ case s == "use-vc" || s == "usevc" || s == "tcp":
+ // Linux (use-vc), FreeBSD (usevc) and OpenBSD (tcp) option:
+ // http://man7.org/linux/man-pages/man5/resolv.conf.5.html
+ // "Sets RES_USEVC in _res.options.
+ // This option forces the use of TCP for DNS resolutions."
+ // https://www.freebsd.org/cgi/man.cgi?query=resolv.conf&sektion=5&manpath=freebsd-release-ports
+ // https://man.openbsd.org/resolv.conf.5
+ conf.useTCP = true
+ case s == "trust-ad":
+ conf.trustAD = true
+ case s == "edns0":
+ // We use EDNS by default.
+ // Ignore this option.
+ case s == "no-reload":
+ conf.noReload = true
+ default:
+ conf.unknownOpt = true
+ }
+ }
+
+ case "lookup":
+ // OpenBSD option:
+ // https://www.openbsd.org/cgi-bin/man.cgi/OpenBSD-current/man5/resolv.conf.5
+ // "the legal space-separated values are: bind, file, yp"
+ conf.lookup = f[1:]
+
+ default:
+ conf.unknownOpt = true
+ }
+ }
+ if len(conf.servers) == 0 {
+ conf.servers = defaultNS
+ }
+ if len(conf.search) == 0 {
+ conf.search = dnsDefaultSearch()
+ }
+ return conf
+}
+
+func dnsDefaultSearch() []string {
+ hn, err := getHostname()
+ if err != nil {
+ // best effort
+ return nil
+ }
+ if i := bytealg.IndexByteString(hn, '.'); i >= 0 && i < len(hn)-1 {
+ return []string{ensureRooted(hn[i+1:])}
+ }
+ return nil
+}
+
+func ensureRooted(s string) string {
+ if len(s) > 0 && s[len(s)-1] == '.' {
+ return s
+ }
+ return s + "."
+}
diff --git a/go/src/net/dnsconfig_unix_test.go b/go/src/net/dnsconfig_unix_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..4db1c5a4af9e5336fb41ae254550b1dff520732a
--- /dev/null
+++ b/go/src/net/dnsconfig_unix_test.go
@@ -0,0 +1,315 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+package net
+
+import (
+ "errors"
+ "io/fs"
+ "os"
+ "reflect"
+ "slices"
+ "strings"
+ "testing"
+ "time"
+)
+
+var dnsReadConfigTests = []struct {
+ name string
+ want *dnsConfig
+}{
+ {
+ name: "testdata/resolv.conf",
+ want: &dnsConfig{
+ servers: []string{"8.8.8.8:53", "[2001:4860:4860::8888]:53", "[fe80::1%lo0]:53"},
+ search: []string{"localdomain."},
+ ndots: 5,
+ timeout: 10 * time.Second,
+ attempts: 3,
+ rotate: true,
+ unknownOpt: true, // the "options attempts 3" line
+ },
+ },
+ {
+ name: "testdata/domain-resolv.conf",
+ want: &dnsConfig{
+ servers: []string{"8.8.8.8:53"},
+ search: []string{"localdomain."},
+ ndots: 1,
+ timeout: 5 * time.Second,
+ attempts: 2,
+ },
+ },
+ {
+ name: "testdata/search-resolv.conf",
+ want: &dnsConfig{
+ servers: []string{"8.8.8.8:53"},
+ search: []string{"test.", "invalid."},
+ ndots: 1,
+ timeout: 5 * time.Second,
+ attempts: 2,
+ },
+ },
+ {
+ name: "testdata/search-single-dot-resolv.conf",
+ want: &dnsConfig{
+ servers: []string{"8.8.8.8:53"},
+ search: []string{},
+ ndots: 1,
+ timeout: 5 * time.Second,
+ attempts: 2,
+ },
+ },
+ {
+ name: "testdata/empty-resolv.conf",
+ want: &dnsConfig{
+ servers: defaultNS,
+ ndots: 1,
+ timeout: 5 * time.Second,
+ attempts: 2,
+ search: []string{"domain.local."},
+ },
+ },
+ {
+ name: "testdata/invalid-ndots-resolv.conf",
+ want: &dnsConfig{
+ servers: defaultNS,
+ ndots: 0,
+ timeout: 5 * time.Second,
+ attempts: 2,
+ search: []string{"domain.local."},
+ },
+ },
+ {
+ name: "testdata/large-ndots-resolv.conf",
+ want: &dnsConfig{
+ servers: defaultNS,
+ ndots: 15,
+ timeout: 5 * time.Second,
+ attempts: 2,
+ search: []string{"domain.local."},
+ },
+ },
+ {
+ name: "testdata/negative-ndots-resolv.conf",
+ want: &dnsConfig{
+ servers: defaultNS,
+ ndots: 0,
+ timeout: 5 * time.Second,
+ attempts: 2,
+ search: []string{"domain.local."},
+ },
+ },
+ {
+ name: "testdata/openbsd-resolv.conf",
+ want: &dnsConfig{
+ ndots: 1,
+ timeout: 5 * time.Second,
+ attempts: 2,
+ lookup: []string{"file", "bind"},
+ servers: []string{"169.254.169.254:53", "10.240.0.1:53"},
+ search: []string{"c.symbolic-datum-552.internal."},
+ },
+ },
+ {
+ name: "testdata/single-request-resolv.conf",
+ want: &dnsConfig{
+ servers: defaultNS,
+ ndots: 1,
+ singleRequest: true,
+ timeout: 5 * time.Second,
+ attempts: 2,
+ search: []string{"domain.local."},
+ },
+ },
+ {
+ name: "testdata/single-request-reopen-resolv.conf",
+ want: &dnsConfig{
+ servers: defaultNS,
+ ndots: 1,
+ singleRequest: true,
+ timeout: 5 * time.Second,
+ attempts: 2,
+ search: []string{"domain.local."},
+ },
+ },
+ {
+ name: "testdata/linux-use-vc-resolv.conf",
+ want: &dnsConfig{
+ servers: defaultNS,
+ ndots: 1,
+ useTCP: true,
+ timeout: 5 * time.Second,
+ attempts: 2,
+ search: []string{"domain.local."},
+ },
+ },
+ {
+ name: "testdata/freebsd-usevc-resolv.conf",
+ want: &dnsConfig{
+ servers: defaultNS,
+ ndots: 1,
+ useTCP: true,
+ timeout: 5 * time.Second,
+ attempts: 2,
+ search: []string{"domain.local."},
+ },
+ },
+ {
+ name: "testdata/openbsd-tcp-resolv.conf",
+ want: &dnsConfig{
+ servers: defaultNS,
+ ndots: 1,
+ useTCP: true,
+ timeout: 5 * time.Second,
+ attempts: 2,
+ search: []string{"domain.local."},
+ },
+ },
+}
+
+func TestDNSReadConfig(t *testing.T) {
+ origGetHostname := getHostname
+ defer func() { getHostname = origGetHostname }()
+ getHostname = func() (string, error) { return "host.domain.local", nil }
+
+ for _, tt := range dnsReadConfigTests {
+ want := *tt.want
+ if len(want.search) == 0 {
+ want.search = dnsDefaultSearch()
+ }
+ conf := dnsReadConfig(tt.name)
+ if conf.err != nil {
+ t.Fatal(conf.err)
+ }
+ conf.mtime = time.Time{}
+ if !reflect.DeepEqual(conf, &want) {
+ t.Errorf("%s:\ngot: %+v\nwant: %+v", tt.name, conf, want)
+ }
+ }
+}
+
+func TestDNSReadMissingFile(t *testing.T) {
+ origGetHostname := getHostname
+ defer func() { getHostname = origGetHostname }()
+ getHostname = func() (string, error) { return "host.domain.local", nil }
+
+ conf := dnsReadConfig("a-nonexistent-file")
+ if !os.IsNotExist(conf.err) {
+ t.Errorf("missing resolv.conf:\ngot: %v\nwant: %v", conf.err, fs.ErrNotExist)
+ }
+ conf.err = nil
+ want := &dnsConfig{
+ servers: defaultNS,
+ ndots: 1,
+ timeout: 5 * time.Second,
+ attempts: 2,
+ search: []string{"domain.local."},
+ }
+ if !reflect.DeepEqual(conf, want) {
+ t.Errorf("missing resolv.conf:\ngot: %+v\nwant: %+v", conf, want)
+ }
+}
+
+var dnsDefaultSearchTests = []struct {
+ name string
+ err error
+ want []string
+}{
+ {
+ name: "host.long.domain.local",
+ want: []string{"long.domain.local."},
+ },
+ {
+ name: "host.local",
+ want: []string{"local."},
+ },
+ {
+ name: "host",
+ want: nil,
+ },
+ {
+ name: "host.domain.local",
+ err: errors.New("errored"),
+ want: nil,
+ },
+ {
+ // ensures we don't return []string{""}
+ // which causes duplicate lookups
+ name: "foo.",
+ want: nil,
+ },
+}
+
+func TestDNSDefaultSearch(t *testing.T) {
+ origGetHostname := getHostname
+ defer func() { getHostname = origGetHostname }()
+
+ for _, tt := range dnsDefaultSearchTests {
+ getHostname = func() (string, error) { return tt.name, tt.err }
+ got := dnsDefaultSearch()
+ if !slices.Equal(got, tt.want) {
+ t.Errorf("dnsDefaultSearch with hostname %q and error %+v = %q, wanted %q", tt.name, tt.err, got, tt.want)
+ }
+ }
+}
+
+func TestDNSNameLength(t *testing.T) {
+ origGetHostname := getHostname
+ defer func() { getHostname = origGetHostname }()
+ getHostname = func() (string, error) { return "host.domain.local", nil }
+
+ var char63 = ""
+ for i := 0; i < 63; i++ {
+ char63 += "a"
+ }
+ longDomain := strings.Repeat(char63+".", 5) + "example"
+
+ for _, tt := range dnsReadConfigTests {
+ conf := dnsReadConfig(tt.name)
+ if conf.err != nil {
+ t.Fatal(conf.err)
+ }
+
+ suffixList := tt.want.search
+ if len(suffixList) == 0 {
+ suffixList = dnsDefaultSearch()
+ }
+
+ var shortestSuffix int
+ for _, suffix := range suffixList {
+ if shortestSuffix == 0 || len(suffix) < shortestSuffix {
+ shortestSuffix = len(suffix)
+ }
+ }
+
+ // Test a name that will be maximally long when prefixing the shortest
+ // suffix (accounting for the intervening dot).
+ longName := longDomain[len(longDomain)-254+1+shortestSuffix:]
+ if longName[0] == '.' || longName[1] == '.' {
+ longName = "aa." + longName[3:]
+ }
+ for _, fqdn := range conf.nameList(longName) {
+ if len(fqdn) > 254 {
+ t.Errorf("got %d; want less than or equal to 254", len(fqdn))
+ }
+ }
+
+ // Now test a name that's too long for suffixing.
+ unsuffixable := "a." + longName[1:]
+ unsuffixableResults := conf.nameList(unsuffixable)
+ if len(unsuffixableResults) != 1 {
+ t.Errorf("suffixed names %v; want []", unsuffixableResults[1:])
+ }
+
+ // Now test a name that's too long for DNS.
+ tooLong := "a." + longDomain
+ tooLongResults := conf.nameList(tooLong)
+ if tooLongResults != nil {
+ t.Errorf("suffixed names %v; want nil", tooLongResults)
+ }
+ }
+}
diff --git a/go/src/net/dnsconfig_windows.go b/go/src/net/dnsconfig_windows.go
new file mode 100644
index 0000000000000000000000000000000000000000..34455309dbb297b513ed84b5eaa1540b4b0142a1
--- /dev/null
+++ b/go/src/net/dnsconfig_windows.go
@@ -0,0 +1,68 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "internal/syscall/windows"
+ "syscall"
+ "time"
+)
+
+func dnsReadConfig(ignoredFilename string) (conf *dnsConfig) {
+ conf = &dnsConfig{
+ ndots: 1,
+ timeout: 5 * time.Second,
+ attempts: 2,
+ }
+ defer func() {
+ if len(conf.servers) == 0 {
+ conf.servers = defaultNS
+ }
+ }()
+ aas, err := adapterAddresses()
+ if err != nil {
+ return
+ }
+
+ for _, aa := range aas {
+ // Only take interfaces whose OperStatus is IfOperStatusUp(0x01) into DNS configs.
+ if aa.OperStatus != windows.IfOperStatusUp {
+ continue
+ }
+
+ // Only take interfaces which have at least one gateway
+ if aa.FirstGatewayAddress == nil {
+ continue
+ }
+
+ for dns := aa.FirstDnsServerAddress; dns != nil; dns = dns.Next {
+ sa, err := dns.Address.Sockaddr.Sockaddr()
+ if err != nil {
+ continue
+ }
+ var ip IP
+ switch sa := sa.(type) {
+ case *syscall.SockaddrInet4:
+ ip = IPv4(sa.Addr[0], sa.Addr[1], sa.Addr[2], sa.Addr[3])
+ case *syscall.SockaddrInet6:
+ ip = make(IP, IPv6len)
+ copy(ip, sa.Addr[:])
+ if ip[0] == 0xfe && ip[1] == 0xc0 {
+ // fec0/10 IPv6 addresses are site local anycast DNS
+ // addresses Microsoft sets by default if no other
+ // IPv6 DNS address is set. Site local anycast is
+ // deprecated since 2004, see
+ // https://datatracker.ietf.org/doc/html/rfc3879
+ continue
+ }
+ default:
+ // Unexpected type.
+ continue
+ }
+ conf.servers = append(conf.servers, JoinHostPort(ip.String(), "53"))
+ }
+ }
+ return conf
+}
diff --git a/go/src/net/dnsname_test.go b/go/src/net/dnsname_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..601a33af9f4c0af4ea06c7d780064ed69a60112e
--- /dev/null
+++ b/go/src/net/dnsname_test.go
@@ -0,0 +1,84 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "strings"
+ "testing"
+)
+
+type dnsNameTest struct {
+ name string
+ result bool
+}
+
+var dnsNameTests = []dnsNameTest{
+ // RFC 2181, section 11.
+ {"_xmpp-server._tcp.google.com", true},
+ {"foo.com", true},
+ {"1foo.com", true},
+ {"26.0.0.73.com", true},
+ {"10-0-0-1", true},
+ {"fo-o.com", true},
+ {"fo1o.com", true},
+ {"foo1.com", true},
+ {"a.b..com", false},
+ {"a.b-.com", false},
+ {"a.b.com-", false},
+ {"a.b..", false},
+ {"b.com.", true},
+}
+
+func emitDNSNameTest(ch chan<- dnsNameTest) {
+ defer close(ch)
+ var char63 = ""
+ for i := 0; i < 63; i++ {
+ char63 += "a"
+ }
+ char64 := char63 + "a"
+ longDomain := strings.Repeat(char63+".", 5) + "example"
+
+ for _, tc := range dnsNameTests {
+ ch <- tc
+ }
+
+ ch <- dnsNameTest{char63 + ".com", true}
+ ch <- dnsNameTest{char64 + ".com", false}
+
+ // Remember: wire format is two octets longer than presentation
+ // (length octets for the first and [root] last labels).
+ // 253 is fine:
+ ch <- dnsNameTest{longDomain[len(longDomain)-253:], true}
+ // A terminal dot doesn't contribute to length:
+ ch <- dnsNameTest{longDomain[len(longDomain)-253:] + ".", true}
+ // 254 is bad:
+ ch <- dnsNameTest{longDomain[len(longDomain)-254:], false}
+}
+
+func TestDNSName(t *testing.T) {
+ ch := make(chan dnsNameTest)
+ go emitDNSNameTest(ch)
+ for tc := range ch {
+ if isDomainName(tc.name) != tc.result {
+ t.Errorf("isDomainName(%q) = %v; want %v", tc.name, !tc.result, tc.result)
+ }
+ }
+}
+
+func BenchmarkDNSName(b *testing.B) {
+ testHookUninstaller.Do(uninstallTestHooks)
+
+ benchmarks := append(dnsNameTests, []dnsNameTest{
+ {strings.Repeat("a", 63), true},
+ {strings.Repeat("a", 64), false},
+ }...)
+ for n := 0; n < b.N; n++ {
+ for _, tc := range benchmarks {
+ if isDomainName(tc.name) != tc.result {
+ b.Errorf("isDomainName(%q) = %v; want %v", tc.name, !tc.result, tc.result)
+ }
+ }
+ }
+}
diff --git a/go/src/net/error_plan9.go b/go/src/net/error_plan9.go
new file mode 100644
index 0000000000000000000000000000000000000000..caad133b774dc5c43e60a06fedb0502ea3948d9a
--- /dev/null
+++ b/go/src/net/error_plan9.go
@@ -0,0 +1,9 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+func isConnError(err error) bool {
+ return false
+}
diff --git a/go/src/net/error_plan9_test.go b/go/src/net/error_plan9_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..f86c96c0d2fbac145fa22f8f4983373e171e222f
--- /dev/null
+++ b/go/src/net/error_plan9_test.go
@@ -0,0 +1,22 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import "syscall"
+
+var (
+ errOpNotSupported = syscall.EPLAN9
+
+ abortedConnRequestErrors []error
+)
+
+func isPlatformError(err error) bool {
+ _, ok := err.(syscall.ErrorString)
+ return ok
+}
+
+func isENOBUFS(err error) bool {
+ return false // ENOBUFS is Unix-specific
+}
diff --git a/go/src/net/error_posix.go b/go/src/net/error_posix.go
new file mode 100644
index 0000000000000000000000000000000000000000..84f80440454b37dd01d6e01f56c7422d2f63e15c
--- /dev/null
+++ b/go/src/net/error_posix.go
@@ -0,0 +1,21 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || js || wasip1 || windows
+
+package net
+
+import (
+ "os"
+ "syscall"
+)
+
+// wrapSyscallError takes an error and a syscall name. If the error is
+// a syscall.Errno, it wraps it in an os.SyscallError using the syscall name.
+func wrapSyscallError(name string, err error) error {
+ if _, ok := err.(syscall.Errno); ok {
+ err = os.NewSyscallError(name, err)
+ }
+ return err
+}
diff --git a/go/src/net/error_posix_test.go b/go/src/net/error_posix_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..081176f771aebf72fa02563e862e82da678dc3f8
--- /dev/null
+++ b/go/src/net/error_posix_test.go
@@ -0,0 +1,34 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !plan9
+
+package net
+
+import (
+ "os"
+ "syscall"
+ "testing"
+)
+
+func TestSpuriousENOTAVAIL(t *testing.T) {
+ for _, tt := range []struct {
+ error
+ ok bool
+ }{
+ {syscall.EADDRNOTAVAIL, true},
+ {&os.SyscallError{Syscall: "syscall", Err: syscall.EADDRNOTAVAIL}, true},
+ {&OpError{Op: "op", Err: syscall.EADDRNOTAVAIL}, true},
+ {&OpError{Op: "op", Err: &os.SyscallError{Syscall: "syscall", Err: syscall.EADDRNOTAVAIL}}, true},
+
+ {syscall.EINVAL, false},
+ {&os.SyscallError{Syscall: "syscall", Err: syscall.EINVAL}, false},
+ {&OpError{Op: "op", Err: syscall.EINVAL}, false},
+ {&OpError{Op: "op", Err: &os.SyscallError{Syscall: "syscall", Err: syscall.EINVAL}}, false},
+ } {
+ if ok := spuriousENOTAVAIL(tt.error); ok != tt.ok {
+ t.Errorf("spuriousENOTAVAIL(%v) = %v; want %v", tt.error, ok, tt.ok)
+ }
+ }
+}
diff --git a/go/src/net/error_test.go b/go/src/net/error_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..8026144c3da7f523090f52c7829e956877b93baa
--- /dev/null
+++ b/go/src/net/error_test.go
@@ -0,0 +1,818 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "context"
+ "errors"
+ "fmt"
+ "internal/poll"
+ "io"
+ "io/fs"
+ "net/internal/socktest"
+ "os"
+ "runtime"
+ "strings"
+ "testing"
+ "time"
+)
+
+func (e *OpError) isValid() error {
+ if e.Op == "" {
+ return fmt.Errorf("OpError.Op is empty: %v", e)
+ }
+ if e.Net == "" {
+ return fmt.Errorf("OpError.Net is empty: %v", e)
+ }
+ for _, addr := range []Addr{e.Source, e.Addr} {
+ switch addr := addr.(type) {
+ case nil:
+ case *TCPAddr:
+ if addr == nil {
+ return fmt.Errorf("OpError.Source or Addr is non-nil interface: %#v, %v", addr, e)
+ }
+ case *UDPAddr:
+ if addr == nil {
+ return fmt.Errorf("OpError.Source or Addr is non-nil interface: %#v, %v", addr, e)
+ }
+ case *IPAddr:
+ if addr == nil {
+ return fmt.Errorf("OpError.Source or Addr is non-nil interface: %#v, %v", addr, e)
+ }
+ case *IPNet:
+ if addr == nil {
+ return fmt.Errorf("OpError.Source or Addr is non-nil interface: %#v, %v", addr, e)
+ }
+ case *UnixAddr:
+ if addr == nil {
+ return fmt.Errorf("OpError.Source or Addr is non-nil interface: %#v, %v", addr, e)
+ }
+ case *pipeAddr:
+ if addr == nil {
+ return fmt.Errorf("OpError.Source or Addr is non-nil interface: %#v, %v", addr, e)
+ }
+ case fileAddr:
+ if addr == "" {
+ return fmt.Errorf("OpError.Source or Addr is empty: %#v, %v", addr, e)
+ }
+ default:
+ return fmt.Errorf("OpError.Source or Addr is unknown type: %T, %v", addr, e)
+ }
+ }
+ if e.Err == nil {
+ return fmt.Errorf("OpError.Err is empty: %v", e)
+ }
+ return nil
+}
+
+// parseDialError parses nestedErr and reports whether it is a valid
+// error value from Dial, Listen functions.
+// It returns nil when nestedErr is valid.
+func parseDialError(nestedErr error) error {
+ if nestedErr == nil {
+ return nil
+ }
+
+ switch err := nestedErr.(type) {
+ case *OpError:
+ if err := err.isValid(); err != nil {
+ return err
+ }
+ nestedErr = err.Err
+ goto second
+ }
+ return fmt.Errorf("unexpected type on 1st nested level: %T", nestedErr)
+
+second:
+ if isPlatformError(nestedErr) {
+ return nil
+ }
+ switch err := nestedErr.(type) {
+ case *AddrError, *timeoutError, *DNSError, InvalidAddrError, *ParseError, *poll.DeadlineExceededError, UnknownNetworkError:
+ return nil
+ case interface{ isAddrinfoErrno() }:
+ return nil
+ case *os.SyscallError:
+ nestedErr = err.Err
+ goto third
+ case *fs.PathError: // for Plan 9
+ nestedErr = err.Err
+ goto third
+ }
+ switch nestedErr {
+ case errCanceled, ErrClosed, errMissingAddress, errNoSuitableAddress,
+ context.DeadlineExceeded, context.Canceled:
+ return nil
+ }
+ return fmt.Errorf("unexpected type on 2nd nested level: %T", nestedErr)
+
+third:
+ if isPlatformError(nestedErr) {
+ return nil
+ }
+ return fmt.Errorf("unexpected type on 3rd nested level: %T", nestedErr)
+}
+
+var dialErrorTests = []struct {
+ network, address string
+}{
+ {"foo", ""},
+ {"bar", "baz"},
+ {"datakit", "mh/astro/r70"},
+ {"tcp", ""},
+ {"tcp", "127.0.0.1:☺"},
+ {"tcp", "no-such-name:80"},
+ {"tcp", "mh/astro/r70:http"},
+
+ {"tcp", JoinHostPort("127.0.0.1", "-1")},
+ {"tcp", JoinHostPort("127.0.0.1", "123456789")},
+ {"udp", JoinHostPort("127.0.0.1", "-1")},
+ {"udp", JoinHostPort("127.0.0.1", "123456789")},
+ {"ip:icmp", "127.0.0.1"},
+
+ {"unix", "/path/to/somewhere"},
+ {"unixgram", "/path/to/somewhere"},
+ {"unixpacket", "/path/to/somewhere"},
+}
+
+func TestDialError(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9":
+ t.Skipf("%s does not have full support of socktest", runtime.GOOS)
+ }
+
+ origTestHookLookupIP := testHookLookupIP
+ defer func() { testHookLookupIP = origTestHookLookupIP }()
+ testHookLookupIP = func(ctx context.Context, fn func(context.Context, string, string) ([]IPAddr, error), network, host string) ([]IPAddr, error) {
+ return nil, &DNSError{Err: "dial error test", Name: "name", Server: "server", IsTimeout: true}
+ }
+ sw.Set(socktest.FilterConnect, func(so *socktest.Status) (socktest.AfterFilter, error) {
+ return nil, errOpNotSupported
+ })
+ defer sw.Set(socktest.FilterConnect, nil)
+
+ d := Dialer{Timeout: someTimeout}
+ for i, tt := range dialErrorTests {
+ t.Run(fmt.Sprint(i), func(t *testing.T) {
+ c, err := d.Dial(tt.network, tt.address)
+ if err == nil {
+ t.Errorf("should fail; %s:%s->%s", c.LocalAddr().Network(), c.LocalAddr(), c.RemoteAddr())
+ c.Close()
+ return
+ }
+ if tt.network == "tcp" || tt.network == "udp" {
+ nerr := err
+ if op, ok := nerr.(*OpError); ok {
+ nerr = op.Err
+ }
+ if sys, ok := nerr.(*os.SyscallError); ok {
+ nerr = sys.Err
+ }
+ if nerr == errOpNotSupported {
+ t.Fatalf("should fail without %v; %s:%s->", nerr, tt.network, tt.address)
+ }
+ }
+ if c != nil {
+ t.Errorf("Dial returned non-nil interface %T(%v) with err != nil", c, c)
+ }
+ if err = parseDialError(err); err != nil {
+ t.Error(err)
+ }
+ })
+ }
+}
+
+func TestProtocolDialError(t *testing.T) {
+ switch runtime.GOOS {
+ case "solaris", "illumos":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+
+ for _, network := range []string{"tcp", "udp", "ip:4294967296", "unix", "unixpacket", "unixgram"} {
+ var err error
+ switch network {
+ case "tcp":
+ _, err = DialTCP(network, nil, &TCPAddr{Port: 1 << 16})
+ case "udp":
+ _, err = DialUDP(network, nil, &UDPAddr{Port: 1 << 16})
+ case "ip:4294967296":
+ _, err = DialIP(network, nil, nil)
+ case "unix", "unixpacket", "unixgram":
+ _, err = DialUnix(network, nil, &UnixAddr{Name: "//"})
+ }
+ if err == nil {
+ t.Errorf("%s: should fail", network)
+ continue
+ }
+ if err := parseDialError(err); err != nil {
+ t.Errorf("%s: %v", network, err)
+ continue
+ }
+ t.Logf("%s: error as expected: %v", network, err)
+ }
+}
+
+func TestDialAddrError(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+
+ if !supportsIPv4() || !supportsIPv6() {
+ t.Skip("both IPv4 and IPv6 are required")
+ }
+
+ for _, tt := range []struct {
+ network string
+ lit string
+ addr *TCPAddr
+ }{
+ {"tcp4", "::1", nil},
+ {"tcp4", "", &TCPAddr{IP: IPv6loopback}},
+ // We don't test the {"tcp6", "byte sequence", nil}
+ // case for now because there is no easy way to
+ // control name resolution.
+ {"tcp6", "", &TCPAddr{IP: IP{0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef}}},
+ } {
+ desc := tt.lit
+ if desc == "" {
+ desc = tt.addr.String()
+ }
+ t.Run(fmt.Sprintf("%s/%s", tt.network, desc), func(t *testing.T) {
+ var err error
+ var c Conn
+ var op string
+ if tt.lit != "" {
+ c, err = Dial(tt.network, JoinHostPort(tt.lit, "0"))
+ op = fmt.Sprintf("Dial(%q, %q)", tt.network, JoinHostPort(tt.lit, "0"))
+ } else {
+ c, err = DialTCP(tt.network, nil, tt.addr)
+ op = fmt.Sprintf("DialTCP(%q, %q)", tt.network, tt.addr)
+ }
+ t.Logf("%s: %v", op, err)
+ if err == nil {
+ c.Close()
+ t.Fatalf("%s succeeded, want error", op)
+ }
+ if perr := parseDialError(err); perr != nil {
+ t.Fatal(perr)
+ }
+ operr := err.(*OpError).Err
+ aerr, ok := operr.(*AddrError)
+ if !ok {
+ t.Fatalf("OpError.Err is %T, want *AddrError", operr)
+ }
+ want := tt.lit
+ if tt.lit == "" {
+ want = tt.addr.IP.String()
+ }
+ if aerr.Addr != want {
+ t.Errorf("error Addr=%q, want %q", aerr.Addr, want)
+ }
+ })
+ }
+}
+
+var listenErrorTests = []struct {
+ network, address string
+}{
+ {"foo", ""},
+ {"bar", "baz"},
+ {"datakit", "mh/astro/r70"},
+ {"tcp", "127.0.0.1:☺"},
+ {"tcp", "no-such-name:80"},
+ {"tcp", "mh/astro/r70:http"},
+
+ {"tcp", JoinHostPort("127.0.0.1", "-1")},
+ {"tcp", JoinHostPort("127.0.0.1", "123456789")},
+
+ {"unix", "/path/to/somewhere"},
+ {"unixpacket", "/path/to/somewhere"},
+}
+
+func TestListenError(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9":
+ t.Skipf("%s does not have full support of socktest", runtime.GOOS)
+ }
+
+ origTestHookLookupIP := testHookLookupIP
+ defer func() { testHookLookupIP = origTestHookLookupIP }()
+ testHookLookupIP = func(_ context.Context, fn func(context.Context, string, string) ([]IPAddr, error), network, host string) ([]IPAddr, error) {
+ return nil, &DNSError{Err: "listen error test", Name: "name", Server: "server", IsTimeout: true}
+ }
+ sw.Set(socktest.FilterListen, func(so *socktest.Status) (socktest.AfterFilter, error) {
+ return nil, errOpNotSupported
+ })
+ defer sw.Set(socktest.FilterListen, nil)
+
+ for i, tt := range listenErrorTests {
+ t.Run(fmt.Sprintf("%s_%s", tt.network, tt.address), func(t *testing.T) {
+ ln, err := Listen(tt.network, tt.address)
+ if err == nil {
+ t.Errorf("#%d: should fail; %s:%s->", i, ln.Addr().Network(), ln.Addr())
+ ln.Close()
+ return
+ }
+ if tt.network == "tcp" {
+ nerr := err
+ if op, ok := nerr.(*OpError); ok {
+ nerr = op.Err
+ }
+ if sys, ok := nerr.(*os.SyscallError); ok {
+ nerr = sys.Err
+ }
+ if nerr == errOpNotSupported {
+ t.Fatalf("#%d: should fail without %v; %s:%s->", i, nerr, tt.network, tt.address)
+ }
+ }
+ if ln != nil {
+ t.Errorf("Listen returned non-nil interface %T(%v) with err != nil", ln, ln)
+ }
+ if err = parseDialError(err); err != nil {
+ t.Errorf("#%d: %v", i, err)
+ }
+ })
+ }
+}
+
+var listenPacketErrorTests = []struct {
+ network, address string
+}{
+ {"foo", ""},
+ {"bar", "baz"},
+ {"datakit", "mh/astro/r70"},
+ {"udp", "127.0.0.1:☺"},
+ {"udp", "no-such-name:80"},
+ {"udp", "mh/astro/r70:http"},
+
+ {"udp", JoinHostPort("127.0.0.1", "-1")},
+ {"udp", JoinHostPort("127.0.0.1", "123456789")},
+}
+
+func TestListenPacketError(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9":
+ t.Skipf("%s does not have full support of socktest", runtime.GOOS)
+ }
+
+ origTestHookLookupIP := testHookLookupIP
+ defer func() { testHookLookupIP = origTestHookLookupIP }()
+ testHookLookupIP = func(_ context.Context, fn func(context.Context, string, string) ([]IPAddr, error), network, host string) ([]IPAddr, error) {
+ return nil, &DNSError{Err: "listen error test", Name: "name", Server: "server", IsTimeout: true}
+ }
+
+ for i, tt := range listenPacketErrorTests {
+ t.Run(fmt.Sprintf("%s_%s", tt.network, tt.address), func(t *testing.T) {
+ c, err := ListenPacket(tt.network, tt.address)
+ if err == nil {
+ t.Errorf("#%d: should fail; %s:%s->", i, c.LocalAddr().Network(), c.LocalAddr())
+ c.Close()
+ return
+ }
+ if c != nil {
+ t.Errorf("ListenPacket returned non-nil interface %T(%v) with err != nil", c, c)
+ }
+ if err = parseDialError(err); err != nil {
+ t.Errorf("#%d: %v", i, err)
+ }
+ })
+ }
+}
+
+func TestProtocolListenError(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+
+ for _, network := range []string{"tcp", "udp", "ip:4294967296", "unix", "unixpacket", "unixgram"} {
+ var err error
+ switch network {
+ case "tcp":
+ _, err = ListenTCP(network, &TCPAddr{Port: 1 << 16})
+ case "udp":
+ _, err = ListenUDP(network, &UDPAddr{Port: 1 << 16})
+ case "ip:4294967296":
+ _, err = ListenIP(network, nil)
+ case "unix", "unixpacket":
+ _, err = ListenUnix(network, &UnixAddr{Name: "//"})
+ case "unixgram":
+ _, err = ListenUnixgram(network, &UnixAddr{Name: "//"})
+ }
+ if err == nil {
+ t.Errorf("%s: should fail", network)
+ continue
+ }
+ if err = parseDialError(err); err != nil {
+ t.Errorf("%s: %v", network, err)
+ continue
+ }
+ }
+}
+
+// parseReadError parses nestedErr and reports whether it is a valid
+// error value from Read functions.
+// It returns nil when nestedErr is valid.
+func parseReadError(nestedErr error) error {
+ if nestedErr == nil {
+ return nil
+ }
+
+ switch err := nestedErr.(type) {
+ case *OpError:
+ if err := err.isValid(); err != nil {
+ return err
+ }
+ nestedErr = err.Err
+ goto second
+ }
+ if nestedErr == io.EOF {
+ return nil
+ }
+ return fmt.Errorf("unexpected type on 1st nested level: %T", nestedErr)
+
+second:
+ if isPlatformError(nestedErr) {
+ return nil
+ }
+ switch err := nestedErr.(type) {
+ case *os.SyscallError:
+ nestedErr = err.Err
+ goto third
+ }
+ switch nestedErr {
+ case ErrClosed, errTimeout, poll.ErrNotPollable, os.ErrDeadlineExceeded:
+ return nil
+ }
+ return fmt.Errorf("unexpected type on 2nd nested level: %T", nestedErr)
+
+third:
+ if isPlatformError(nestedErr) {
+ return nil
+ }
+ return fmt.Errorf("unexpected type on 3rd nested level: %T", nestedErr)
+}
+
+// parseWriteError parses nestedErr and reports whether it is a valid
+// error value from Write functions.
+// It returns nil when nestedErr is valid.
+func parseWriteError(nestedErr error) error {
+ if nestedErr == nil {
+ return nil
+ }
+
+ switch err := nestedErr.(type) {
+ case *OpError:
+ if err := err.isValid(); err != nil {
+ return err
+ }
+ nestedErr = err.Err
+ goto second
+ }
+ return fmt.Errorf("unexpected type on 1st nested level: %T", nestedErr)
+
+second:
+ if isPlatformError(nestedErr) {
+ return nil
+ }
+ switch err := nestedErr.(type) {
+ case *AddrError, *timeoutError, *DNSError, InvalidAddrError, *ParseError, *poll.DeadlineExceededError, UnknownNetworkError:
+ return nil
+ case interface{ isAddrinfoErrno() }:
+ return nil
+ case *os.SyscallError:
+ nestedErr = err.Err
+ goto third
+ }
+ switch nestedErr {
+ case errCanceled, ErrClosed, errMissingAddress, errTimeout, os.ErrDeadlineExceeded, ErrWriteToConnected, io.ErrUnexpectedEOF:
+ return nil
+ }
+ return fmt.Errorf("unexpected type on 2nd nested level: %T", nestedErr)
+
+third:
+ if isPlatformError(nestedErr) {
+ return nil
+ }
+ return fmt.Errorf("unexpected type on 3rd nested level: %T", nestedErr)
+}
+
+// parseCloseError parses nestedErr and reports whether it is a valid
+// error value from Close functions.
+// It returns nil when nestedErr is valid.
+func parseCloseError(nestedErr error, isShutdown bool) error {
+ if nestedErr == nil {
+ return nil
+ }
+
+ // Because historically we have not exported the error that we
+ // return for an operation on a closed network connection,
+ // there are programs that test for the exact error string.
+ // Verify that string here so that we don't break those
+ // programs unexpectedly. See issues #4373 and #19252.
+ want := "use of closed network connection"
+ if !isShutdown && !strings.Contains(nestedErr.Error(), want) {
+ return fmt.Errorf("error string %q does not contain expected string %q", nestedErr, want)
+ }
+
+ if !isShutdown && !errors.Is(nestedErr, ErrClosed) {
+ return fmt.Errorf("errors.Is(%v, errClosed) returns false, want true", nestedErr)
+ }
+
+ switch err := nestedErr.(type) {
+ case *OpError:
+ if err := err.isValid(); err != nil {
+ return err
+ }
+ nestedErr = err.Err
+ goto second
+ }
+ return fmt.Errorf("unexpected type on 1st nested level: %T", nestedErr)
+
+second:
+ if isPlatformError(nestedErr) {
+ return nil
+ }
+ switch err := nestedErr.(type) {
+ case *os.SyscallError:
+ nestedErr = err.Err
+ goto third
+ case *fs.PathError: // for Plan 9
+ nestedErr = err.Err
+ goto third
+ }
+ switch nestedErr {
+ case ErrClosed:
+ return nil
+ }
+ return fmt.Errorf("unexpected type on 2nd nested level: %T", nestedErr)
+
+third:
+ if isPlatformError(nestedErr) {
+ return nil
+ }
+ switch nestedErr {
+ case fs.ErrClosed: // for Plan 9
+ return nil
+ }
+ return fmt.Errorf("unexpected type on 3rd nested level: %T", nestedErr)
+}
+
+func TestCloseError(t *testing.T) {
+ t.Run("tcp", func(t *testing.T) {
+ ln := newLocalListener(t, "tcp")
+ defer ln.Close()
+ c, err := Dial(ln.Addr().Network(), ln.Addr().String())
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer c.Close()
+
+ for i := 0; i < 3; i++ {
+ err = c.(*TCPConn).CloseRead()
+ if perr := parseCloseError(err, true); perr != nil {
+ t.Errorf("#%d: %v", i, perr)
+ }
+ }
+ for i := 0; i < 3; i++ {
+ err = c.(*TCPConn).CloseWrite()
+ if perr := parseCloseError(err, true); perr != nil {
+ t.Errorf("#%d: %v", i, perr)
+ }
+ }
+ for i := 0; i < 3; i++ {
+ err = c.Close()
+ if perr := parseCloseError(err, false); perr != nil {
+ t.Errorf("#%d: %v", i, perr)
+ }
+ err = ln.Close()
+ if perr := parseCloseError(err, false); perr != nil {
+ t.Errorf("#%d: %v", i, perr)
+ }
+ }
+ })
+
+ t.Run("udp", func(t *testing.T) {
+ if !testableNetwork("udp") {
+ t.Skipf("skipping: udp not available")
+ }
+
+ pc, err := ListenPacket("udp", "127.0.0.1:0")
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer pc.Close()
+
+ for i := 0; i < 3; i++ {
+ err = pc.Close()
+ if perr := parseCloseError(err, false); perr != nil {
+ t.Errorf("#%d: %v", i, perr)
+ }
+ }
+ })
+}
+
+// parseAcceptError parses nestedErr and reports whether it is a valid
+// error value from Accept functions.
+// It returns nil when nestedErr is valid.
+func parseAcceptError(nestedErr error) error {
+ if nestedErr == nil {
+ return nil
+ }
+
+ switch err := nestedErr.(type) {
+ case *OpError:
+ if err := err.isValid(); err != nil {
+ return err
+ }
+ nestedErr = err.Err
+ goto second
+ }
+ return fmt.Errorf("unexpected type on 1st nested level: %T", nestedErr)
+
+second:
+ if isPlatformError(nestedErr) {
+ return nil
+ }
+ switch err := nestedErr.(type) {
+ case *os.SyscallError:
+ nestedErr = err.Err
+ goto third
+ case *fs.PathError: // for Plan 9
+ nestedErr = err.Err
+ goto third
+ }
+ switch nestedErr {
+ case ErrClosed, errTimeout, poll.ErrNotPollable, os.ErrDeadlineExceeded:
+ return nil
+ }
+ return fmt.Errorf("unexpected type on 2nd nested level: %T", nestedErr)
+
+third:
+ if isPlatformError(nestedErr) {
+ return nil
+ }
+ return fmt.Errorf("unexpected type on 3rd nested level: %T", nestedErr)
+}
+
+func TestAcceptError(t *testing.T) {
+ handler := func(ls *localServer, ln Listener) {
+ for {
+ ln.(*TCPListener).SetDeadline(time.Now().Add(5 * time.Millisecond))
+ c, err := ln.Accept()
+ if perr := parseAcceptError(err); perr != nil {
+ t.Error(perr)
+ }
+ if err != nil {
+ if c != nil {
+ t.Errorf("Accept returned non-nil interface %T(%v) with err != nil", c, c)
+ }
+ if nerr, ok := err.(Error); !ok || (!nerr.Timeout() && !nerr.Temporary()) {
+ return
+ }
+ continue
+ }
+ c.Close()
+ }
+ }
+ ls := newLocalServer(t, "tcp")
+ if err := ls.buildup(handler); err != nil {
+ ls.teardown()
+ t.Fatal(err)
+ }
+
+ time.Sleep(100 * time.Millisecond)
+ ls.teardown()
+}
+
+// parseCommonError parses nestedErr and reports whether it is a valid
+// error value from miscellaneous functions.
+// It returns nil when nestedErr is valid.
+func parseCommonError(nestedErr error) error {
+ if nestedErr == nil {
+ return nil
+ }
+
+ switch err := nestedErr.(type) {
+ case *OpError:
+ if err := err.isValid(); err != nil {
+ return err
+ }
+ nestedErr = err.Err
+ goto second
+ }
+ return fmt.Errorf("unexpected type on 1st nested level: %T", nestedErr)
+
+second:
+ if isPlatformError(nestedErr) {
+ return nil
+ }
+ switch err := nestedErr.(type) {
+ case *os.SyscallError:
+ nestedErr = err.Err
+ goto third
+ case *os.LinkError:
+ nestedErr = err.Err
+ goto third
+ case *fs.PathError:
+ nestedErr = err.Err
+ goto third
+ }
+ switch nestedErr {
+ case ErrClosed:
+ return nil
+ }
+ return fmt.Errorf("unexpected type on 2nd nested level: %T", nestedErr)
+
+third:
+ if isPlatformError(nestedErr) {
+ return nil
+ }
+ return fmt.Errorf("unexpected type on 3rd nested level: %T", nestedErr)
+}
+
+func TestFileError(t *testing.T) {
+ f, err := os.CreateTemp("", "go-nettest")
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer os.Remove(f.Name())
+ defer f.Close()
+
+ c, err := FileConn(f)
+ if err != nil {
+ if c != nil {
+ t.Errorf("FileConn returned non-nil interface %T(%v) with err != nil", c, c)
+ }
+ if perr := parseCommonError(err); perr != nil {
+ t.Error(perr)
+ }
+ } else {
+ c.Close()
+ t.Error("should fail")
+ }
+ ln, err := FileListener(f)
+ if err != nil {
+ if ln != nil {
+ t.Errorf("FileListener returned non-nil interface %T(%v) with err != nil", ln, ln)
+ }
+ if perr := parseCommonError(err); perr != nil {
+ t.Error(perr)
+ }
+ } else {
+ ln.Close()
+ t.Error("should fail")
+ }
+ pc, err := FilePacketConn(f)
+ if err != nil {
+ if pc != nil {
+ t.Errorf("FilePacketConn returned non-nil interface %T(%v) with err != nil", pc, pc)
+ }
+ if perr := parseCommonError(err); perr != nil {
+ t.Error(perr)
+ }
+ } else {
+ pc.Close()
+ t.Error("should fail")
+ }
+
+ ln = newLocalListener(t, "tcp")
+
+ for i := 0; i < 3; i++ {
+ f, err := ln.(*TCPListener).File()
+ if err != nil {
+ if perr := parseCommonError(err); perr != nil {
+ t.Error(perr)
+ }
+ } else {
+ f.Close()
+ }
+ ln.Close()
+ }
+}
+
+func parseLookupPortError(nestedErr error) error {
+ if nestedErr == nil {
+ return nil
+ }
+
+ switch nestedErr.(type) {
+ case *AddrError, *DNSError:
+ return nil
+ case *fs.PathError: // for Plan 9
+ return nil
+ }
+ return fmt.Errorf("unexpected type on 1st nested level: %T", nestedErr)
+}
+
+func TestContextError(t *testing.T) {
+ if !errors.Is(errCanceled, context.Canceled) {
+ t.Error("errCanceled is not context.Canceled")
+ }
+ if !errors.Is(errTimeout, context.DeadlineExceeded) {
+ t.Error("errTimeout is not context.DeadlineExceeded")
+ }
+}
diff --git a/go/src/net/error_unix.go b/go/src/net/error_unix.go
new file mode 100644
index 0000000000000000000000000000000000000000..d6948670b6a305606753214e3f0398b5f4b6df9a
--- /dev/null
+++ b/go/src/net/error_unix.go
@@ -0,0 +1,16 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || js || wasip1
+
+package net
+
+import "syscall"
+
+func isConnError(err error) bool {
+ if se, ok := err.(syscall.Errno); ok {
+ return se == syscall.ECONNRESET || se == syscall.ECONNABORTED
+ }
+ return false
+}
diff --git a/go/src/net/error_unix_test.go b/go/src/net/error_unix_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..963ba21f1a0ac1dd6ba05fe8886a258bdda6ee8d
--- /dev/null
+++ b/go/src/net/error_unix_test.go
@@ -0,0 +1,38 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !plan9 && !windows
+
+package net
+
+import (
+ "errors"
+ "os"
+ "syscall"
+)
+
+var (
+ errOpNotSupported = syscall.EOPNOTSUPP
+
+ abortedConnRequestErrors = []error{syscall.ECONNABORTED} // see accept in fd_unix.go
+)
+
+func isPlatformError(err error) bool {
+ _, ok := err.(syscall.Errno)
+ return ok
+}
+
+func samePlatformError(err, want error) bool {
+ if op, ok := err.(*OpError); ok {
+ err = op.Err
+ }
+ if sys, ok := err.(*os.SyscallError); ok {
+ err = sys.Err
+ }
+ return err == want
+}
+
+func isENOBUFS(err error) bool {
+ return errors.Is(err, syscall.ENOBUFS)
+}
diff --git a/go/src/net/error_windows.go b/go/src/net/error_windows.go
new file mode 100644
index 0000000000000000000000000000000000000000..570b97b278b7f90a46cdaadb74d73de3a1f45def
--- /dev/null
+++ b/go/src/net/error_windows.go
@@ -0,0 +1,14 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import "syscall"
+
+func isConnError(err error) bool {
+ if se, ok := err.(syscall.Errno); ok {
+ return se == syscall.WSAECONNRESET || se == syscall.WSAECONNABORTED
+ }
+ return false
+}
diff --git a/go/src/net/error_windows_test.go b/go/src/net/error_windows_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..7847af055160f332b06062dc7a6eb921efeb0b34
--- /dev/null
+++ b/go/src/net/error_windows_test.go
@@ -0,0 +1,28 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "errors"
+ "syscall"
+)
+
+var (
+ errOpNotSupported = syscall.EOPNOTSUPP
+
+ abortedConnRequestErrors = []error{syscall.ERROR_NETNAME_DELETED, syscall.WSAECONNRESET} // see accept in fd_windows.go
+)
+
+func isPlatformError(err error) bool {
+ _, ok := err.(syscall.Errno)
+ return ok
+}
+
+func isENOBUFS(err error) bool {
+ // syscall.ENOBUFS is a completely made-up value on Windows: we don't expect
+ // a real system call to ever actually return it. However, since it is already
+ // defined in the syscall package we may as well check for it.
+ return errors.Is(err, syscall.ENOBUFS)
+}
diff --git a/go/src/net/example_test.go b/go/src/net/example_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..12c83970940ab0647faa03d67592a61c9afbb275
--- /dev/null
+++ b/go/src/net/example_test.go
@@ -0,0 +1,387 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net_test
+
+import (
+ "context"
+ "fmt"
+ "io"
+ "log"
+ "net"
+ "time"
+)
+
+func ExampleListener() {
+ // Listen on TCP port 2000 on all available unicast and
+ // anycast IP addresses of the local system.
+ l, err := net.Listen("tcp", ":2000")
+ if err != nil {
+ log.Fatal(err)
+ }
+ defer l.Close()
+ for {
+ // Wait for a connection.
+ conn, err := l.Accept()
+ if err != nil {
+ log.Fatal(err)
+ }
+ // Handle the connection in a new goroutine.
+ // The loop then returns to accepting, so that
+ // multiple connections may be served concurrently.
+ go func(c net.Conn) {
+ // Echo all incoming data.
+ io.Copy(c, c)
+ // Shut down the connection.
+ c.Close()
+ }(conn)
+ }
+}
+
+func ExampleDialer() {
+ var d net.Dialer
+ ctx, cancel := context.WithTimeout(context.Background(), time.Minute)
+ defer cancel()
+
+ conn, err := d.DialContext(ctx, "tcp", "localhost:12345")
+ if err != nil {
+ log.Fatalf("Failed to dial: %v", err)
+ }
+ defer conn.Close()
+
+ if _, err := conn.Write([]byte("Hello, World!")); err != nil {
+ log.Fatal(err)
+ }
+}
+
+func ExampleDialer_unix() {
+ // DialUnix does not take a context.Context parameter. This example shows
+ // how to dial a Unix socket with a Context. Note that the Context only
+ // applies to the dial operation; it does not apply to the connection once
+ // it has been established.
+ var d net.Dialer
+ ctx, cancel := context.WithTimeout(context.Background(), time.Minute)
+ defer cancel()
+
+ d.LocalAddr = nil // if you have a local addr, add it here
+ raddr := net.UnixAddr{Name: "/path/to/unix.sock", Net: "unix"}
+ conn, err := d.DialContext(ctx, "unix", raddr.String())
+ if err != nil {
+ log.Fatalf("Failed to dial: %v", err)
+ }
+ defer conn.Close()
+ if _, err := conn.Write([]byte("Hello, socket!")); err != nil {
+ log.Fatal(err)
+ }
+}
+
+func ExampleIPv4() {
+ fmt.Println(net.IPv4(8, 8, 8, 8))
+
+ // Output:
+ // 8.8.8.8
+}
+
+func ExampleParseCIDR() {
+ ipv4Addr, ipv4Net, err := net.ParseCIDR("192.0.2.1/24")
+ if err != nil {
+ log.Fatal(err)
+ }
+ fmt.Println(ipv4Addr)
+ fmt.Println(ipv4Net)
+
+ ipv6Addr, ipv6Net, err := net.ParseCIDR("2001:db8:a0b:12f0::1/32")
+ if err != nil {
+ log.Fatal(err)
+ }
+ fmt.Println(ipv6Addr)
+ fmt.Println(ipv6Net)
+
+ // Output:
+ // 192.0.2.1
+ // 192.0.2.0/24
+ // 2001:db8:a0b:12f0::1
+ // 2001:db8::/32
+}
+
+func ExampleParseIP() {
+ fmt.Println(net.ParseIP("192.0.2.1"))
+ fmt.Println(net.ParseIP("2001:db8::68"))
+ fmt.Println(net.ParseIP("192.0.2"))
+
+ // Output:
+ // 192.0.2.1
+ // 2001:db8::68
+ //
+}
+
+func ExampleIP_DefaultMask() {
+ ip := net.ParseIP("192.0.2.1")
+ fmt.Println(ip.DefaultMask())
+
+ // Output:
+ // ffffff00
+}
+
+func ExampleIP_Equal() {
+ ipv4DNS := net.ParseIP("8.8.8.8")
+ ipv4Lo := net.ParseIP("127.0.0.1")
+ ipv6DNS := net.ParseIP("0:0:0:0:0:FFFF:0808:0808")
+
+ fmt.Println(ipv4DNS.Equal(ipv4DNS))
+ fmt.Println(ipv4DNS.Equal(ipv4Lo))
+ fmt.Println(ipv4DNS.Equal(ipv6DNS))
+
+ // Output:
+ // true
+ // false
+ // true
+}
+
+func ExampleIP_IsGlobalUnicast() {
+ ipv6Global := net.ParseIP("2000::")
+ ipv6UniqLocal := net.ParseIP("2000::")
+ ipv6Multi := net.ParseIP("FF00::")
+
+ ipv4Private := net.ParseIP("10.255.0.0")
+ ipv4Public := net.ParseIP("8.8.8.8")
+ ipv4Broadcast := net.ParseIP("255.255.255.255")
+
+ fmt.Println(ipv6Global.IsGlobalUnicast())
+ fmt.Println(ipv6UniqLocal.IsGlobalUnicast())
+ fmt.Println(ipv6Multi.IsGlobalUnicast())
+
+ fmt.Println(ipv4Private.IsGlobalUnicast())
+ fmt.Println(ipv4Public.IsGlobalUnicast())
+ fmt.Println(ipv4Broadcast.IsGlobalUnicast())
+
+ // Output:
+ // true
+ // true
+ // false
+ // true
+ // true
+ // false
+}
+
+func ExampleIP_IsInterfaceLocalMulticast() {
+ ipv6InterfaceLocalMulti := net.ParseIP("ff01::1")
+ ipv6Global := net.ParseIP("2000::")
+ ipv4 := net.ParseIP("255.0.0.0")
+
+ fmt.Println(ipv6InterfaceLocalMulti.IsInterfaceLocalMulticast())
+ fmt.Println(ipv6Global.IsInterfaceLocalMulticast())
+ fmt.Println(ipv4.IsInterfaceLocalMulticast())
+
+ // Output:
+ // true
+ // false
+ // false
+}
+
+func ExampleIP_IsLinkLocalMulticast() {
+ ipv6LinkLocalMulti := net.ParseIP("ff02::2")
+ ipv6LinkLocalUni := net.ParseIP("fe80::")
+ ipv4LinkLocalMulti := net.ParseIP("224.0.0.0")
+ ipv4LinkLocalUni := net.ParseIP("169.254.0.0")
+
+ fmt.Println(ipv6LinkLocalMulti.IsLinkLocalMulticast())
+ fmt.Println(ipv6LinkLocalUni.IsLinkLocalMulticast())
+ fmt.Println(ipv4LinkLocalMulti.IsLinkLocalMulticast())
+ fmt.Println(ipv4LinkLocalUni.IsLinkLocalMulticast())
+
+ // Output:
+ // true
+ // false
+ // true
+ // false
+}
+
+func ExampleIP_IsLinkLocalUnicast() {
+ ipv6LinkLocalUni := net.ParseIP("fe80::")
+ ipv6Global := net.ParseIP("2000::")
+ ipv4LinkLocalUni := net.ParseIP("169.254.0.0")
+ ipv4LinkLocalMulti := net.ParseIP("224.0.0.0")
+
+ fmt.Println(ipv6LinkLocalUni.IsLinkLocalUnicast())
+ fmt.Println(ipv6Global.IsLinkLocalUnicast())
+ fmt.Println(ipv4LinkLocalUni.IsLinkLocalUnicast())
+ fmt.Println(ipv4LinkLocalMulti.IsLinkLocalUnicast())
+
+ // Output:
+ // true
+ // false
+ // true
+ // false
+}
+
+func ExampleIP_IsLoopback() {
+ ipv6Lo := net.ParseIP("::1")
+ ipv6 := net.ParseIP("ff02::1")
+ ipv4Lo := net.ParseIP("127.0.0.0")
+ ipv4 := net.ParseIP("128.0.0.0")
+
+ fmt.Println(ipv6Lo.IsLoopback())
+ fmt.Println(ipv6.IsLoopback())
+ fmt.Println(ipv4Lo.IsLoopback())
+ fmt.Println(ipv4.IsLoopback())
+
+ // Output:
+ // true
+ // false
+ // true
+ // false
+}
+
+func ExampleIP_IsMulticast() {
+ ipv6Multi := net.ParseIP("FF00::")
+ ipv6LinkLocalMulti := net.ParseIP("ff02::1")
+ ipv6Lo := net.ParseIP("::1")
+ ipv4Multi := net.ParseIP("239.0.0.0")
+ ipv4LinkLocalMulti := net.ParseIP("224.0.0.0")
+ ipv4Lo := net.ParseIP("127.0.0.0")
+
+ fmt.Println(ipv6Multi.IsMulticast())
+ fmt.Println(ipv6LinkLocalMulti.IsMulticast())
+ fmt.Println(ipv6Lo.IsMulticast())
+ fmt.Println(ipv4Multi.IsMulticast())
+ fmt.Println(ipv4LinkLocalMulti.IsMulticast())
+ fmt.Println(ipv4Lo.IsMulticast())
+
+ // Output:
+ // true
+ // true
+ // false
+ // true
+ // true
+ // false
+}
+
+func ExampleIP_IsPrivate() {
+ ipv6Private := net.ParseIP("fc00::")
+ ipv6Public := net.ParseIP("fe00::")
+ ipv4Private := net.ParseIP("10.255.0.0")
+ ipv4Public := net.ParseIP("11.0.0.0")
+
+ fmt.Println(ipv6Private.IsPrivate())
+ fmt.Println(ipv6Public.IsPrivate())
+ fmt.Println(ipv4Private.IsPrivate())
+ fmt.Println(ipv4Public.IsPrivate())
+
+ // Output:
+ // true
+ // false
+ // true
+ // false
+}
+
+func ExampleIP_IsUnspecified() {
+ ipv6Unspecified := net.ParseIP("::")
+ ipv6Specified := net.ParseIP("fe00::")
+ ipv4Unspecified := net.ParseIP("0.0.0.0")
+ ipv4Specified := net.ParseIP("8.8.8.8")
+
+ fmt.Println(ipv6Unspecified.IsUnspecified())
+ fmt.Println(ipv6Specified.IsUnspecified())
+ fmt.Println(ipv4Unspecified.IsUnspecified())
+ fmt.Println(ipv4Specified.IsUnspecified())
+
+ // Output:
+ // true
+ // false
+ // true
+ // false
+}
+
+func ExampleIP_Mask() {
+ ipv4Addr := net.ParseIP("192.0.2.1")
+ // This mask corresponds to a /24 subnet for IPv4.
+ ipv4Mask := net.CIDRMask(24, 32)
+ fmt.Println(ipv4Addr.Mask(ipv4Mask))
+
+ ipv6Addr := net.ParseIP("2001:db8:a0b:12f0::1")
+ // This mask corresponds to a /32 subnet for IPv6.
+ ipv6Mask := net.CIDRMask(32, 128)
+ fmt.Println(ipv6Addr.Mask(ipv6Mask))
+
+ // Output:
+ // 192.0.2.0
+ // 2001:db8::
+}
+
+func ExampleIP_String() {
+ ipv6 := net.IP{0xfc, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
+ ipv4 := net.IPv4(10, 255, 0, 0)
+
+ fmt.Println(ipv6.String())
+ fmt.Println(ipv4.String())
+
+ // Output:
+ // fc00::
+ // 10.255.0.0
+}
+
+func ExampleIP_To16() {
+ ipv6 := net.IP{0xfc, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
+ ipv4 := net.IPv4(10, 255, 0, 0)
+
+ fmt.Println(ipv6.To16())
+ fmt.Println(ipv4.To16())
+
+ // Output:
+ // fc00::
+ // 10.255.0.0
+}
+
+func ExampleIP_To4() {
+ ipv6 := net.IP{0xfc, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
+ ipv4 := net.IPv4(10, 255, 0, 0)
+
+ fmt.Println(ipv6.To4())
+ fmt.Println(ipv4.To4())
+
+ // Output:
+ //
+ // 10.255.0.0
+}
+
+func ExampleCIDRMask() {
+ // This mask corresponds to a /31 subnet for IPv4.
+ fmt.Println(net.CIDRMask(31, 32))
+
+ // This mask corresponds to a /64 subnet for IPv6.
+ fmt.Println(net.CIDRMask(64, 128))
+
+ // Output:
+ // fffffffe
+ // ffffffffffffffff0000000000000000
+}
+
+func ExampleIPv4Mask() {
+ fmt.Println(net.IPv4Mask(255, 255, 255, 0))
+
+ // Output:
+ // ffffff00
+}
+
+func ExampleUDPConn_WriteTo() {
+ // Unlike Dial, ListenPacket creates a connection without any
+ // association with peers.
+ conn, err := net.ListenPacket("udp", ":0")
+ if err != nil {
+ log.Fatal(err)
+ }
+ defer conn.Close()
+
+ dst, err := net.ResolveUDPAddr("udp", "192.0.2.1:2000")
+ if err != nil {
+ log.Fatal(err)
+ }
+
+ // The connection can write data to the desired address.
+ _, err = conn.WriteTo([]byte("data"), dst)
+ if err != nil {
+ log.Fatal(err)
+ }
+}
diff --git a/go/src/net/external_test.go b/go/src/net/external_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..9b918f8986a1f5ad813629918fbd142c0bb37d3a
--- /dev/null
+++ b/go/src/net/external_test.go
@@ -0,0 +1,165 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "fmt"
+ "internal/testenv"
+ "io"
+ "strings"
+ "testing"
+)
+
+func TestResolveGoogle(t *testing.T) {
+ testenv.MustHaveExternalNetwork(t)
+
+ if !supportsIPv4() || !supportsIPv6() || !*testIPv4 || !*testIPv6 {
+ t.Skip("both IPv4 and IPv6 are required")
+ }
+
+ for _, network := range []string{"tcp", "tcp4", "tcp6"} {
+ addr, err := ResolveTCPAddr(network, "www.google.com:http")
+ if err != nil {
+ t.Error(err)
+ continue
+ }
+ switch {
+ case network == "tcp" && addr.IP.To4() == nil:
+ fallthrough
+ case network == "tcp4" && addr.IP.To4() == nil:
+ t.Errorf("got %v; want an IPv4 address on %s", addr, network)
+ case network == "tcp6" && (addr.IP.To16() == nil || addr.IP.To4() != nil):
+ t.Errorf("got %v; want an IPv6 address on %s", addr, network)
+ }
+ }
+}
+
+var dialGoogleTests = []struct {
+ dial func(string, string) (Conn, error)
+ unreachableNetwork string
+ networks []string
+ addrs []string
+}{
+ {
+ dial: (&Dialer{DualStack: true}).Dial,
+ networks: []string{"tcp", "tcp4", "tcp6"},
+ addrs: []string{"www.google.com:http"},
+ },
+ {
+ dial: Dial,
+ unreachableNetwork: "tcp6",
+ networks: []string{"tcp", "tcp4"},
+ },
+ {
+ dial: Dial,
+ unreachableNetwork: "tcp4",
+ networks: []string{"tcp", "tcp6"},
+ },
+}
+
+func TestDialGoogle(t *testing.T) {
+ testenv.MustHaveExternalNetwork(t)
+
+ if !supportsIPv4() || !supportsIPv6() || !*testIPv4 || !*testIPv6 {
+ t.Skip("both IPv4 and IPv6 are required")
+ }
+
+ var err error
+ dialGoogleTests[1].addrs, dialGoogleTests[2].addrs, err = googleLiteralAddrs()
+ if err != nil {
+ t.Error(err)
+ }
+ for _, tt := range dialGoogleTests {
+ for _, network := range tt.networks {
+ disableSocketConnect(tt.unreachableNetwork)
+ for _, addr := range tt.addrs {
+ if err := fetchGoogle(tt.dial, network, addr); err != nil {
+ t.Error(err)
+ }
+ }
+ enableSocketConnect()
+ }
+ }
+}
+
+var (
+ literalAddrs4 = [...]string{
+ "%d.%d.%d.%d:80",
+ "www.google.com:80",
+ "%d.%d.%d.%d:http",
+ "www.google.com:http",
+ "[::ffff:%d.%d.%d.%d]:80",
+ "[::ffff:%02x%02x:%02x%02x]:80",
+ "[0:0:0:0:0000:ffff:%d.%d.%d.%d]:80",
+ "[0:0:0:0:000000:ffff:%d.%d.%d.%d]:80",
+ "[0:0:0:0::ffff:%d.%d.%d.%d]:80",
+ }
+ literalAddrs6 = [...]string{
+ "[%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x]:80",
+ "ipv6.google.com:80",
+ "[%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x]:http",
+ "ipv6.google.com:http",
+ }
+)
+
+func googleLiteralAddrs() (lits4, lits6 []string, err error) {
+ ips, err := LookupIP("www.google.com")
+ if err != nil {
+ return nil, nil, err
+ }
+ if len(ips) == 0 {
+ return nil, nil, nil
+ }
+ var ip4, ip6 IP
+ for _, ip := range ips {
+ if ip4 == nil && ip.To4() != nil {
+ ip4 = ip.To4()
+ }
+ if ip6 == nil && ip.To16() != nil && ip.To4() == nil {
+ ip6 = ip.To16()
+ }
+ if ip4 != nil && ip6 != nil {
+ break
+ }
+ }
+ if ip4 != nil {
+ for i, lit4 := range literalAddrs4 {
+ if strings.Contains(lit4, "%") {
+ literalAddrs4[i] = fmt.Sprintf(lit4, ip4[0], ip4[1], ip4[2], ip4[3])
+ }
+ }
+ lits4 = literalAddrs4[:]
+ }
+ if ip6 != nil {
+ for i, lit6 := range literalAddrs6 {
+ if strings.Contains(lit6, "%") {
+ literalAddrs6[i] = fmt.Sprintf(lit6, ip6[0], ip6[1], ip6[2], ip6[3], ip6[4], ip6[5], ip6[6], ip6[7], ip6[8], ip6[9], ip6[10], ip6[11], ip6[12], ip6[13], ip6[14], ip6[15])
+ }
+ }
+ lits6 = literalAddrs6[:]
+ }
+ return
+}
+
+func fetchGoogle(dial func(string, string) (Conn, error), network, address string) error {
+ c, err := dial(network, address)
+ if err != nil {
+ return err
+ }
+ defer c.Close()
+ req := []byte("GET /robots.txt HTTP/1.0\r\nHost: www.google.com\r\n\r\n")
+ if _, err := c.Write(req); err != nil {
+ return err
+ }
+ b := make([]byte, 1000)
+ n, err := io.ReadFull(c, b)
+ if err != nil {
+ return err
+ }
+ if n < 1000 {
+ return fmt.Errorf("short read from %s:%s->%s", network, c.RemoteAddr(), c.LocalAddr())
+ }
+ return nil
+}
diff --git a/go/src/net/fd_fake.go b/go/src/net/fd_fake.go
new file mode 100644
index 0000000000000000000000000000000000000000..946805ab940b7a2c49f42113759759501dbb70d2
--- /dev/null
+++ b/go/src/net/fd_fake.go
@@ -0,0 +1,171 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build js || wasip1
+
+package net
+
+import (
+ "internal/poll"
+ "runtime"
+ "time"
+)
+
+const (
+ readSyscallName = "fd_read"
+ writeSyscallName = "fd_write"
+)
+
+// Network file descriptor.
+type netFD struct {
+ pfd poll.FD
+
+ // immutable until Close
+ family int
+ sotype int
+ isConnected bool // handshake completed or use of association with peer
+ net string
+ laddr Addr
+ raddr Addr
+
+ // The only networking available in WASI preview 1 is the ability to
+ // sock_accept on a pre-opened socket, and then fd_read, fd_write,
+ // fd_close, and sock_shutdown on the resulting connection. We
+ // intercept applicable netFD calls on this instance, and then pass
+ // the remainder of the netFD calls to fakeNetFD.
+ *fakeNetFD
+}
+
+func newFD(net string, sysfd int) *netFD {
+ return newPollFD(net, poll.FD{
+ Sysfd: sysfd,
+ IsStream: true,
+ ZeroReadIsEOF: true,
+ })
+}
+
+func newPollFD(net string, pfd poll.FD) *netFD {
+ var laddr Addr
+ var raddr Addr
+ // WASI preview 1 does not have functions like getsockname/getpeername,
+ // so we cannot get access to the underlying IP address used by connections.
+ //
+ // However, listeners created by FileListener are of type *TCPListener,
+ // which can be asserted by a Go program. The (*TCPListener).Addr method
+ // documents that the returned value will be of type *TCPAddr, we satisfy
+ // the documented behavior by creating addresses of the expected type here.
+ switch net {
+ case "tcp":
+ laddr = new(TCPAddr)
+ raddr = new(TCPAddr)
+ case "udp":
+ laddr = new(UDPAddr)
+ raddr = new(UDPAddr)
+ default:
+ laddr = unknownAddr{}
+ raddr = unknownAddr{}
+ }
+ return &netFD{
+ pfd: pfd,
+ net: net,
+ laddr: laddr,
+ raddr: raddr,
+ }
+}
+
+func (fd *netFD) init() error {
+ return fd.pfd.Init(fd.net, true)
+}
+
+func (fd *netFD) name() string {
+ return "unknown"
+}
+
+func (fd *netFD) accept() (netfd *netFD, err error) {
+ if fd.fakeNetFD != nil {
+ return fd.fakeNetFD.accept(fd.laddr)
+ }
+ d, _, errcall, err := fd.pfd.Accept()
+ if err != nil {
+ if errcall != "" {
+ err = wrapSyscallError(errcall, err)
+ }
+ return nil, err
+ }
+ netfd = newFD("tcp", d)
+ if err = netfd.init(); err != nil {
+ netfd.Close()
+ return nil, err
+ }
+ return netfd, nil
+}
+
+func (fd *netFD) setAddr(laddr, raddr Addr) {
+ fd.laddr = laddr
+ fd.raddr = raddr
+ // TODO Replace with runtime.AddCleanup.
+ runtime.SetFinalizer(fd, (*netFD).Close)
+}
+
+func (fd *netFD) Close() error {
+ if fd.fakeNetFD != nil {
+ return fd.fakeNetFD.Close()
+ }
+ // TODO Replace with runtime.AddCleanup.
+ runtime.SetFinalizer(fd, nil)
+ return fd.pfd.Close()
+}
+
+func (fd *netFD) shutdown(how int) error {
+ if fd.fakeNetFD != nil {
+ return nil
+ }
+ err := fd.pfd.Shutdown(how)
+ runtime.KeepAlive(fd)
+ return wrapSyscallError("shutdown", err)
+}
+
+func (fd *netFD) Read(p []byte) (n int, err error) {
+ if fd.fakeNetFD != nil {
+ return fd.fakeNetFD.Read(p)
+ }
+ n, err = fd.pfd.Read(p)
+ runtime.KeepAlive(fd)
+ return n, wrapSyscallError(readSyscallName, err)
+}
+
+func (fd *netFD) Write(p []byte) (nn int, err error) {
+ if fd.fakeNetFD != nil {
+ return fd.fakeNetFD.Write(p)
+ }
+ nn, err = fd.pfd.Write(p)
+ runtime.KeepAlive(fd)
+ return nn, wrapSyscallError(writeSyscallName, err)
+}
+
+func (fd *netFD) SetDeadline(t time.Time) error {
+ if fd.fakeNetFD != nil {
+ return fd.fakeNetFD.SetDeadline(t)
+ }
+ return fd.pfd.SetDeadline(t)
+}
+
+func (fd *netFD) SetReadDeadline(t time.Time) error {
+ if fd.fakeNetFD != nil {
+ return fd.fakeNetFD.SetReadDeadline(t)
+ }
+ return fd.pfd.SetReadDeadline(t)
+}
+
+func (fd *netFD) SetWriteDeadline(t time.Time) error {
+ if fd.fakeNetFD != nil {
+ return fd.fakeNetFD.SetWriteDeadline(t)
+ }
+ return fd.pfd.SetWriteDeadline(t)
+}
+
+type unknownAddr struct{}
+
+func (unknownAddr) Network() string { return "unknown" }
+func (unknownAddr) String() string { return "unknown" }
diff --git a/go/src/net/fd_js.go b/go/src/net/fd_js.go
new file mode 100644
index 0000000000000000000000000000000000000000..0fce036ef13c1cef33a1d603397801c1c4ec5553
--- /dev/null
+++ b/go/src/net/fd_js.go
@@ -0,0 +1,28 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Fake networking for js/wasm. It is intended to allow tests of other package to pass.
+
+//go:build js
+
+package net
+
+import (
+ "os"
+ "syscall"
+)
+
+func (fd *netFD) closeRead() error {
+ if fd.fakeNetFD != nil {
+ return fd.fakeNetFD.closeRead()
+ }
+ return os.NewSyscallError("closeRead", syscall.ENOTSUP)
+}
+
+func (fd *netFD) closeWrite() error {
+ if fd.fakeNetFD != nil {
+ return fd.fakeNetFD.closeWrite()
+ }
+ return os.NewSyscallError("closeRead", syscall.ENOTSUP)
+}
diff --git a/go/src/net/fd_plan9.go b/go/src/net/fd_plan9.go
new file mode 100644
index 0000000000000000000000000000000000000000..66a12e7d7dabdc2c886925f6b0486f2413d72fa3
--- /dev/null
+++ b/go/src/net/fd_plan9.go
@@ -0,0 +1,192 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "internal/poll"
+ "io"
+ "os"
+ "syscall"
+ "time"
+)
+
+// Network file descriptor.
+type netFD struct {
+ pfd poll.FD
+
+ // immutable until Close
+ net string
+ n string
+ dir string
+ listen, ctl, data *os.File
+ laddr, raddr Addr
+ isStream bool
+}
+
+var netdir = "/net" // default network
+
+func newFD(net, name string, listen, ctl, data *os.File, laddr, raddr Addr) (*netFD, error) {
+ ret := &netFD{
+ net: net,
+ n: name,
+ dir: netdir + "/" + net + "/" + name,
+ listen: listen,
+ ctl: ctl, data: data,
+ laddr: laddr,
+ raddr: raddr,
+ }
+ ret.pfd.Destroy = ret.destroy
+ return ret, nil
+}
+
+func (fd *netFD) init() error {
+ // stub for future fd.pd.Init(fd)
+ return nil
+}
+
+func (fd *netFD) name() string {
+ var ls, rs string
+ if fd.laddr != nil {
+ ls = fd.laddr.String()
+ }
+ if fd.raddr != nil {
+ rs = fd.raddr.String()
+ }
+ return fd.net + ":" + ls + "->" + rs
+}
+
+func (fd *netFD) ok() bool { return fd != nil && fd.ctl != nil }
+
+func (fd *netFD) destroy() {
+ if !fd.ok() {
+ return
+ }
+ err := fd.ctl.Close()
+ if fd.data != nil {
+ if err1 := fd.data.Close(); err1 != nil && err == nil {
+ err = err1
+ }
+ }
+ if fd.listen != nil {
+ if err1 := fd.listen.Close(); err1 != nil && err == nil {
+ err = err1
+ }
+ }
+ fd.ctl = nil
+ fd.data = nil
+ fd.listen = nil
+}
+
+func (fd *netFD) Read(b []byte) (n int, err error) {
+ if !fd.ok() || fd.data == nil {
+ return 0, syscall.EINVAL
+ }
+ n, err = fd.pfd.Read(fd.data.Read, b)
+ if fd.net == "udp" && err == io.EOF {
+ n = 0
+ err = nil
+ }
+ return
+}
+
+func (fd *netFD) Write(b []byte) (n int, err error) {
+ if !fd.ok() || fd.data == nil {
+ return 0, syscall.EINVAL
+ }
+ return fd.pfd.Write(fd.data.Write, b)
+}
+
+func (fd *netFD) closeRead() error {
+ if !fd.ok() {
+ return syscall.EINVAL
+ }
+ return syscall.EPLAN9
+}
+
+func (fd *netFD) closeWrite() error {
+ if !fd.ok() {
+ return syscall.EINVAL
+ }
+ return syscall.EPLAN9
+}
+
+func (fd *netFD) Close() error {
+ if err := fd.pfd.Close(); err != nil {
+ return err
+ }
+ if !fd.ok() {
+ return syscall.EINVAL
+ }
+ if fd.net == "tcp" {
+ // The following line is required to unblock Reads.
+ _, err := fd.ctl.WriteString("close")
+ if err != nil {
+ return err
+ }
+ }
+ if fd.net == "udp" {
+ // The following line is required to unblock Reads.
+ // See https://go.dev/issue/72770.
+ fd.SetReadDeadline(time.Now().Add(-time.Hour))
+ }
+ err := fd.ctl.Close()
+ if fd.data != nil {
+ if err1 := fd.data.Close(); err1 != nil && err == nil {
+ err = err1
+ }
+ }
+ if fd.listen != nil {
+ if err1 := fd.listen.Close(); err1 != nil && err == nil {
+ err = err1
+ }
+ }
+ fd.ctl = nil
+ fd.data = nil
+ fd.listen = nil
+ return err
+}
+
+// This method is only called via Conn.
+func (fd *netFD) dup() (*os.File, error) {
+ if !fd.ok() || fd.data == nil {
+ return nil, syscall.EINVAL
+ }
+ return fd.file(fd.data, fd.dir+"/data")
+}
+
+func (l *TCPListener) dup() (*os.File, error) {
+ if !l.fd.ok() {
+ return nil, syscall.EINVAL
+ }
+ return l.fd.file(l.fd.ctl, l.fd.dir+"/ctl")
+}
+
+func (fd *netFD) file(f *os.File, s string) (*os.File, error) {
+ dfd, err := syscall.Dup(int(f.Fd()), -1)
+ if err != nil {
+ return nil, os.NewSyscallError("dup", err)
+ }
+ return os.NewFile(uintptr(dfd), s), nil
+}
+
+func setReadBuffer(fd *netFD, bytes int) error {
+ return syscall.EPLAN9
+}
+
+func setWriteBuffer(fd *netFD, bytes int) error {
+ return syscall.EPLAN9
+}
+
+func (fd *netFD) SetDeadline(t time.Time) error {
+ return fd.pfd.SetDeadline(t)
+}
+
+func (fd *netFD) SetReadDeadline(t time.Time) error {
+ return fd.pfd.SetReadDeadline(t)
+}
+
+func (fd *netFD) SetWriteDeadline(t time.Time) error {
+ return fd.pfd.SetWriteDeadline(t)
+}
diff --git a/go/src/net/fd_posix.go b/go/src/net/fd_posix.go
new file mode 100644
index 0000000000000000000000000000000000000000..023cd534e4206fe8a21c6f44dc8f10403b6b4a63
--- /dev/null
+++ b/go/src/net/fd_posix.go
@@ -0,0 +1,160 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || windows
+
+package net
+
+import (
+ "internal/poll"
+ "runtime"
+ "syscall"
+ "time"
+)
+
+// Network file descriptor.
+type netFD struct {
+ pfd poll.FD
+
+ // immutable until Close
+ family int
+ sotype int
+ isConnected bool // handshake completed or use of association with peer
+ net string
+ laddr Addr
+ raddr Addr
+}
+
+func (fd *netFD) name() string {
+ var ls, rs string
+ if fd.laddr != nil {
+ ls = fd.laddr.String()
+ }
+ if fd.raddr != nil {
+ rs = fd.raddr.String()
+ }
+ return fd.net + ":" + ls + "->" + rs
+}
+
+func (fd *netFD) setAddr(laddr, raddr Addr) {
+ fd.laddr = laddr
+ fd.raddr = raddr
+ // TODO Replace with runtime.AddCleanup.
+ runtime.SetFinalizer(fd, (*netFD).Close)
+}
+
+func (fd *netFD) Close() error {
+ // TODO Replace with runtime.AddCleanup.
+ runtime.SetFinalizer(fd, nil)
+ return fd.pfd.Close()
+}
+
+func (fd *netFD) shutdown(how int) error {
+ err := fd.pfd.Shutdown(how)
+ runtime.KeepAlive(fd)
+ return wrapSyscallError("shutdown", err)
+}
+
+func (fd *netFD) closeRead() error {
+ return fd.shutdown(syscall.SHUT_RD)
+}
+
+func (fd *netFD) closeWrite() error {
+ return fd.shutdown(syscall.SHUT_WR)
+}
+
+func (fd *netFD) Read(p []byte) (n int, err error) {
+ n, err = fd.pfd.Read(p)
+ runtime.KeepAlive(fd)
+ return n, wrapSyscallError(readSyscallName, err)
+}
+
+func (fd *netFD) readFrom(p []byte) (n int, sa syscall.Sockaddr, err error) {
+ n, sa, err = fd.pfd.ReadFrom(p)
+ runtime.KeepAlive(fd)
+ return n, sa, wrapSyscallError(readFromSyscallName, err)
+}
+func (fd *netFD) readFromInet4(p []byte, from *syscall.SockaddrInet4) (n int, err error) {
+ n, err = fd.pfd.ReadFromInet4(p, from)
+ runtime.KeepAlive(fd)
+ return n, wrapSyscallError(readFromSyscallName, err)
+}
+
+func (fd *netFD) readFromInet6(p []byte, from *syscall.SockaddrInet6) (n int, err error) {
+ n, err = fd.pfd.ReadFromInet6(p, from)
+ runtime.KeepAlive(fd)
+ return n, wrapSyscallError(readFromSyscallName, err)
+}
+
+func (fd *netFD) readMsg(p []byte, oob []byte, flags int) (n, oobn, retflags int, sa syscall.Sockaddr, err error) {
+ n, oobn, retflags, sa, err = fd.pfd.ReadMsg(p, oob, flags)
+ runtime.KeepAlive(fd)
+ return n, oobn, retflags, sa, wrapSyscallError(readMsgSyscallName, err)
+}
+
+func (fd *netFD) readMsgInet4(p []byte, oob []byte, flags int, sa *syscall.SockaddrInet4) (n, oobn, retflags int, err error) {
+ n, oobn, retflags, err = fd.pfd.ReadMsgInet4(p, oob, flags, sa)
+ runtime.KeepAlive(fd)
+ return n, oobn, retflags, wrapSyscallError(readMsgSyscallName, err)
+}
+
+func (fd *netFD) readMsgInet6(p []byte, oob []byte, flags int, sa *syscall.SockaddrInet6) (n, oobn, retflags int, err error) {
+ n, oobn, retflags, err = fd.pfd.ReadMsgInet6(p, oob, flags, sa)
+ runtime.KeepAlive(fd)
+ return n, oobn, retflags, wrapSyscallError(readMsgSyscallName, err)
+}
+
+func (fd *netFD) Write(p []byte) (nn int, err error) {
+ nn, err = fd.pfd.Write(p)
+ runtime.KeepAlive(fd)
+ return nn, wrapSyscallError(writeSyscallName, err)
+}
+
+func (fd *netFD) writeTo(p []byte, sa syscall.Sockaddr) (n int, err error) {
+ n, err = fd.pfd.WriteTo(p, sa)
+ runtime.KeepAlive(fd)
+ return n, wrapSyscallError(writeToSyscallName, err)
+}
+
+func (fd *netFD) writeToInet4(p []byte, sa *syscall.SockaddrInet4) (n int, err error) {
+ n, err = fd.pfd.WriteToInet4(p, sa)
+ runtime.KeepAlive(fd)
+ return n, wrapSyscallError(writeToSyscallName, err)
+}
+
+func (fd *netFD) writeToInet6(p []byte, sa *syscall.SockaddrInet6) (n int, err error) {
+ n, err = fd.pfd.WriteToInet6(p, sa)
+ runtime.KeepAlive(fd)
+ return n, wrapSyscallError(writeToSyscallName, err)
+}
+
+func (fd *netFD) writeMsg(p []byte, oob []byte, sa syscall.Sockaddr) (n int, oobn int, err error) {
+ n, oobn, err = fd.pfd.WriteMsg(p, oob, sa)
+ runtime.KeepAlive(fd)
+ return n, oobn, wrapSyscallError(writeMsgSyscallName, err)
+}
+
+func (fd *netFD) writeMsgInet4(p []byte, oob []byte, sa *syscall.SockaddrInet4) (n int, oobn int, err error) {
+ n, oobn, err = fd.pfd.WriteMsgInet4(p, oob, sa)
+ runtime.KeepAlive(fd)
+ return n, oobn, wrapSyscallError(writeMsgSyscallName, err)
+}
+
+func (fd *netFD) writeMsgInet6(p []byte, oob []byte, sa *syscall.SockaddrInet6) (n int, oobn int, err error) {
+ n, oobn, err = fd.pfd.WriteMsgInet6(p, oob, sa)
+ runtime.KeepAlive(fd)
+ return n, oobn, wrapSyscallError(writeMsgSyscallName, err)
+}
+
+func (fd *netFD) SetDeadline(t time.Time) error {
+ return fd.pfd.SetDeadline(t)
+}
+
+func (fd *netFD) SetReadDeadline(t time.Time) error {
+ return fd.pfd.SetReadDeadline(t)
+}
+
+func (fd *netFD) SetWriteDeadline(t time.Time) error {
+ return fd.pfd.SetWriteDeadline(t)
+}
diff --git a/go/src/net/fd_unix.go b/go/src/net/fd_unix.go
new file mode 100644
index 0000000000000000000000000000000000000000..0d4303e2cc0cbee5e64f9bad4c647bc541678c5d
--- /dev/null
+++ b/go/src/net/fd_unix.go
@@ -0,0 +1,184 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+package net
+
+import (
+ "context"
+ "internal/poll"
+ "os"
+ "runtime"
+ "syscall"
+)
+
+const (
+ readSyscallName = "read"
+ readFromSyscallName = "recvfrom"
+ readMsgSyscallName = "recvmsg"
+ writeSyscallName = "write"
+ writeToSyscallName = "sendto"
+ writeMsgSyscallName = "sendmsg"
+)
+
+func newFD(sysfd, family, sotype int, net string) (*netFD, error) {
+ ret := &netFD{
+ pfd: poll.FD{
+ Sysfd: sysfd,
+ IsStream: sotype == syscall.SOCK_STREAM,
+ ZeroReadIsEOF: sotype != syscall.SOCK_DGRAM && sotype != syscall.SOCK_RAW,
+ },
+ family: family,
+ sotype: sotype,
+ net: net,
+ }
+ return ret, nil
+}
+
+func (fd *netFD) init() error {
+ return fd.pfd.Init(fd.net, true)
+}
+
+func (fd *netFD) connect(ctx context.Context, la, ra syscall.Sockaddr) (rsa syscall.Sockaddr, ret error) {
+ // Do not need to call fd.writeLock here,
+ // because fd is not yet accessible to user,
+ // so no concurrent operations are possible.
+ switch err := connectFunc(fd.pfd.Sysfd, ra); err {
+ case syscall.EINPROGRESS, syscall.EALREADY, syscall.EINTR:
+ case nil, syscall.EISCONN:
+ select {
+ case <-ctx.Done():
+ return nil, mapErr(ctx.Err())
+ default:
+ }
+ if err := fd.pfd.Init(fd.net, true); err != nil {
+ return nil, err
+ }
+ runtime.KeepAlive(fd)
+ return nil, nil
+ case syscall.EINVAL:
+ // On Solaris and illumos we can see EINVAL if the socket has
+ // already been accepted and closed by the server. Treat this
+ // as a successful connection--writes to the socket will see
+ // EOF. For details and a test case in C see
+ // https://golang.org/issue/6828.
+ if runtime.GOOS == "solaris" || runtime.GOOS == "illumos" {
+ return nil, nil
+ }
+ fallthrough
+ default:
+ return nil, os.NewSyscallError("connect", err)
+ }
+ if err := fd.pfd.Init(fd.net, true); err != nil {
+ return nil, err
+ }
+
+ ctxDone := ctx.Done()
+ if ctxDone != nil {
+ if deadline, hasDeadline := ctx.Deadline(); hasDeadline {
+ fd.pfd.SetWriteDeadline(deadline)
+ defer fd.pfd.SetWriteDeadline(noDeadline)
+ }
+
+ // Load the hook function synchronously to prevent a race
+ // with test code that restores the old value.
+ testHookCanceledDial := testHookCanceledDial
+ stop := context.AfterFunc(ctx, func() {
+ // Force the runtime's poller to immediately give up
+ // waiting for writability, unblocking waitWrite
+ // below.
+ _ = fd.pfd.SetWriteDeadline(aLongTimeAgo)
+ testHookCanceledDial()
+ })
+ defer func() {
+ if !stop() && ret == nil {
+ // The context.AfterFunc has called or is about to call
+ // SetWriteDeadline, but the connect code below had
+ // returned from waitWrite already and did a successful
+ // connect (ret == nil). Because we've now poisoned the
+ // connection by making it unwritable, don't return a
+ // successful dial. This was issue 16523.
+ ret = mapErr(ctx.Err())
+ // The caller closes fd on error, so there's no need to
+ // wait for the SetWriteDeadline call to return.
+ }
+ }()
+ }
+
+ for {
+ // Performing multiple connect system calls on a
+ // non-blocking socket under Unix variants does not
+ // necessarily result in earlier errors being
+ // returned. Instead, once runtime-integrated network
+ // poller tells us that the socket is ready, get the
+ // SO_ERROR socket option to see if the connection
+ // succeeded or failed. See issue 7474 for further
+ // details.
+ if err := fd.pfd.WaitWrite(); err != nil {
+ select {
+ case <-ctxDone:
+ return nil, mapErr(ctx.Err())
+ default:
+ }
+ return nil, err
+ }
+ nerr, err := getsockoptIntFunc(fd.pfd.Sysfd, syscall.SOL_SOCKET, syscall.SO_ERROR)
+ if err != nil {
+ return nil, os.NewSyscallError("getsockopt", err)
+ }
+ switch err := syscall.Errno(nerr); err {
+ case syscall.EINPROGRESS, syscall.EALREADY, syscall.EINTR:
+ case syscall.EISCONN:
+ return nil, nil
+ case syscall.Errno(0):
+ // The runtime poller can wake us up spuriously;
+ // see issues 14548 and 19289. Check that we are
+ // really connected; if not, wait again.
+ if rsa, err := syscall.Getpeername(fd.pfd.Sysfd); err == nil {
+ return rsa, nil
+ }
+ default:
+ return nil, os.NewSyscallError("connect", err)
+ }
+ runtime.KeepAlive(fd)
+ }
+}
+
+func (fd *netFD) accept() (netfd *netFD, err error) {
+ d, rsa, errcall, err := fd.pfd.Accept()
+ if err != nil {
+ if errcall != "" {
+ err = wrapSyscallError(errcall, err)
+ }
+ return nil, err
+ }
+
+ if netfd, err = newFD(d, fd.family, fd.sotype, fd.net); err != nil {
+ poll.CloseFunc(d)
+ return nil, err
+ }
+ if err = netfd.init(); err != nil {
+ netfd.Close()
+ return nil, err
+ }
+ lsa, _ := syscall.Getsockname(netfd.pfd.Sysfd)
+ netfd.setAddr(netfd.addrFunc()(lsa), netfd.addrFunc()(rsa))
+ return netfd, nil
+}
+
+// Defined in os package.
+func newUnixFile(fd int, name string) *os.File
+
+func (fd *netFD) dup() (f *os.File, err error) {
+ ns, call, err := fd.pfd.Dup()
+ if err != nil {
+ if call != "" {
+ err = os.NewSyscallError(call, err)
+ }
+ return nil, err
+ }
+
+ return newUnixFile(ns, fd.name()), nil
+}
diff --git a/go/src/net/fd_wasip1.go b/go/src/net/fd_wasip1.go
new file mode 100644
index 0000000000000000000000000000000000000000..d50effc05d32bfb4430cadf001b33006f21d8d6f
--- /dev/null
+++ b/go/src/net/fd_wasip1.go
@@ -0,0 +1,25 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build wasip1
+
+package net
+
+import (
+ "syscall"
+)
+
+func (fd *netFD) closeRead() error {
+ if fd.fakeNetFD != nil {
+ return fd.fakeNetFD.closeRead()
+ }
+ return fd.shutdown(syscall.SHUT_RD)
+}
+
+func (fd *netFD) closeWrite() error {
+ if fd.fakeNetFD != nil {
+ return fd.fakeNetFD.closeWrite()
+ }
+ return fd.shutdown(syscall.SHUT_WR)
+}
diff --git a/go/src/net/fd_windows.go b/go/src/net/fd_windows.go
new file mode 100644
index 0000000000000000000000000000000000000000..c28ce045c47811202395fb9477c28325234f8e10
--- /dev/null
+++ b/go/src/net/fd_windows.go
@@ -0,0 +1,261 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "context"
+ "internal/poll"
+ "internal/syscall/windows"
+ "os"
+ "runtime"
+ "syscall"
+ "unsafe"
+)
+
+const (
+ readSyscallName = "wsarecv"
+ readFromSyscallName = "wsarecvfrom"
+ readMsgSyscallName = "wsarecvmsg"
+ writeSyscallName = "wsasend"
+ writeToSyscallName = "wsasendto"
+ writeMsgSyscallName = "wsasendmsg"
+)
+
+func init() {
+ poll.InitWSA()
+}
+
+// canUseConnectEx reports whether we can use the ConnectEx Windows API call
+// for the given network type.
+func canUseConnectEx(net string) bool {
+ switch net {
+ case "tcp", "tcp4", "tcp6":
+ return true
+ }
+ // ConnectEx windows API does not support connectionless sockets.
+ return false
+}
+
+func newFD(sysfd syscall.Handle, family, sotype int, net string) (*netFD, error) {
+ ret := &netFD{
+ pfd: poll.FD{
+ Sysfd: sysfd,
+ IsStream: sotype == syscall.SOCK_STREAM,
+ ZeroReadIsEOF: sotype != syscall.SOCK_DGRAM && sotype != syscall.SOCK_RAW,
+ },
+ family: family,
+ sotype: sotype,
+ net: net,
+ }
+ return ret, nil
+}
+
+func (fd *netFD) init() error {
+ if err := fd.pfd.Init(fd.net, true); err != nil {
+ return err
+ }
+ switch fd.net {
+ case "udp", "udp4", "udp6":
+ // Disable reporting of PORT_UNREACHABLE errors.
+ // See https://go.dev/issue/5834.
+ ret := uint32(0)
+ flag := uint32(0)
+ size := uint32(unsafe.Sizeof(flag))
+ err := syscall.WSAIoctl(fd.pfd.Sysfd, syscall.SIO_UDP_CONNRESET, (*byte)(unsafe.Pointer(&flag)), size, nil, 0, &ret, nil, 0)
+ if err != nil {
+ return wrapSyscallError("wsaioctl", err)
+ }
+ // Disable reporting of NET_UNREACHABLE errors.
+ // See https://go.dev/issue/68614.
+ ret = 0
+ flag = 0
+ size = uint32(unsafe.Sizeof(flag))
+ err = syscall.WSAIoctl(fd.pfd.Sysfd, windows.SIO_UDP_NETRESET, (*byte)(unsafe.Pointer(&flag)), size, nil, 0, &ret, nil, 0)
+ if err != nil {
+ return wrapSyscallError("wsaioctl", err)
+ }
+ }
+ return nil
+}
+
+// Always returns nil for connected peer address result.
+func (fd *netFD) connect(ctx context.Context, la, ra syscall.Sockaddr) (syscall.Sockaddr, error) {
+ // Do not need to call fd.writeLock here,
+ // because fd is not yet accessible to user,
+ // so no concurrent operations are possible.
+ if err := fd.init(); err != nil {
+ return nil, err
+ }
+
+ if ctx.Done() != nil {
+ // Propagate the Context's deadline and cancellation.
+ // If the context is already done, or if it has a nonzero deadline,
+ // ensure that that is applied before the call to ConnectEx begins
+ // so that we don't return spurious connections.
+ defer fd.pfd.SetWriteDeadline(noDeadline)
+
+ if ctx.Err() != nil {
+ fd.pfd.SetWriteDeadline(aLongTimeAgo)
+ } else {
+ if deadline, ok := ctx.Deadline(); ok && !deadline.IsZero() {
+ fd.pfd.SetWriteDeadline(deadline)
+ }
+
+ done := make(chan struct{})
+ stop := context.AfterFunc(ctx, func() {
+ // Force the runtime's poller to immediately give
+ // up waiting for writability.
+ fd.pfd.SetWriteDeadline(aLongTimeAgo)
+ close(done)
+ })
+ defer func() {
+ if !stop() {
+ // Wait for the call to SetWriteDeadline to complete so that we can
+ // reset the deadline if everything else succeeded.
+ <-done
+ }
+ }()
+ }
+ }
+
+ if !canUseConnectEx(fd.net) {
+ err := connectFunc(fd.pfd.Sysfd, ra)
+ return nil, os.NewSyscallError("connect", err)
+ }
+ // ConnectEx windows API requires an unconnected, previously bound socket.
+ if la == nil {
+ switch ra.(type) {
+ case *syscall.SockaddrInet4:
+ la = &syscall.SockaddrInet4{}
+ case *syscall.SockaddrInet6:
+ la = &syscall.SockaddrInet6{}
+ default:
+ panic("unexpected type in connect")
+ }
+ if err := syscall.Bind(fd.pfd.Sysfd, la); err != nil {
+ return nil, os.NewSyscallError("bind", err)
+ }
+ }
+
+ var isloopback bool
+ switch ra := ra.(type) {
+ case *syscall.SockaddrInet4:
+ isloopback = ra.Addr[0] == 127
+ case *syscall.SockaddrInet6:
+ isloopback = ra.Addr == [16]byte(IPv6loopback)
+ default:
+ panic("unexpected type in connect")
+ }
+ if isloopback {
+ // This makes ConnectEx() fails faster if the target port on the localhost
+ // is not reachable, instead of waiting for 2s.
+ params := windows.TCP_INITIAL_RTO_PARAMETERS{
+ Rtt: windows.TCP_INITIAL_RTO_UNSPECIFIED_RTT, // use the default or overridden by the Administrator
+ MaxSynRetransmissions: 1, // minimum possible value before Windows 10.0.16299
+ }
+ if windows.SupportTCPInitialRTONoSYNRetransmissions() {
+ // In Windows 10.0.16299 TCP_INITIAL_RTO_NO_SYN_RETRANSMISSIONS makes ConnectEx() fails instantly.
+ params.MaxSynRetransmissions = windows.TCP_INITIAL_RTO_NO_SYN_RETRANSMISSIONS
+ }
+ var out uint32
+ // Don't abort the connection if WSAIoctl fails, as it is only an optimization.
+ // If it fails reliably, we expect TestDialClosedPortFailFast to detect it.
+ _ = fd.pfd.WSAIoctl(windows.SIO_TCP_INITIAL_RTO, (*byte)(unsafe.Pointer(¶ms)), uint32(unsafe.Sizeof(params)), nil, 0, &out, nil, 0)
+ }
+
+ // Call ConnectEx API.
+ if err := fd.pfd.ConnectEx(ra); err != nil {
+ select {
+ case <-ctx.Done():
+ return nil, mapErr(ctx.Err())
+ default:
+ if _, ok := err.(syscall.Errno); ok {
+ err = os.NewSyscallError("connectex", err)
+ }
+ return nil, err
+ }
+ }
+ // Refresh socket properties.
+ return nil, os.NewSyscallError("setsockopt", syscall.Setsockopt(fd.pfd.Sysfd, syscall.SOL_SOCKET, syscall.SO_UPDATE_CONNECT_CONTEXT, (*byte)(unsafe.Pointer(&fd.pfd.Sysfd)), int32(unsafe.Sizeof(fd.pfd.Sysfd))))
+}
+
+func (c *conn) writeBuffers(v *Buffers) (int64, error) {
+ if !c.ok() {
+ return 0, syscall.EINVAL
+ }
+ n, err := c.fd.writeBuffers(v)
+ if err != nil {
+ return n, &OpError{Op: "wsasend", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+ }
+ return n, nil
+}
+
+func (fd *netFD) writeBuffers(buf *Buffers) (int64, error) {
+ n, err := fd.pfd.Writev((*[][]byte)(buf))
+ runtime.KeepAlive(fd)
+ return n, wrapSyscallError("wsasend", err)
+}
+
+func (fd *netFD) accept() (*netFD, error) {
+ s, rawsa, rsan, errcall, err := fd.pfd.Accept(func() (syscall.Handle, error) {
+ return sysSocket(fd.family, fd.sotype, 0)
+ })
+
+ if err != nil {
+ if errcall != "" {
+ err = wrapSyscallError(errcall, err)
+ }
+ return nil, err
+ }
+
+ // Associate our new socket with IOCP.
+ netfd, err := newFD(s, fd.family, fd.sotype, fd.net)
+ if err != nil {
+ poll.CloseFunc(s)
+ return nil, err
+ }
+ if err := netfd.init(); err != nil {
+ fd.Close()
+ return nil, err
+ }
+
+ // Get local and peer addr out of AcceptEx buffer.
+ var lrsa, rrsa *syscall.RawSockaddrAny
+ var llen, rlen int32
+ syscall.GetAcceptExSockaddrs((*byte)(unsafe.Pointer(&rawsa[0])),
+ 0, rsan, rsan, &lrsa, &llen, &rrsa, &rlen)
+ lsa, _ := lrsa.Sockaddr()
+ rsa, _ := rrsa.Sockaddr()
+
+ netfd.setAddr(netfd.addrFunc()(lsa), netfd.addrFunc()(rsa))
+ return netfd, nil
+}
+
+// Defined in os package.
+func newWindowsFile(h syscall.Handle, name string) *os.File
+
+func (fd *netFD) dup() (*os.File, error) {
+ // Disassociate the IOCP from the socket,
+ // it is not safe to share a duplicated handle
+ // that is associated with IOCP.
+ if err := fd.pfd.DisassociateIOCP(); err != nil {
+ return nil, err
+ }
+ var h syscall.Handle
+ var syserr error
+ err := fd.pfd.RawControl(func(fd uintptr) {
+ h, syserr = dupSocket(syscall.Handle(fd))
+ })
+ if err == nil {
+ err = syserr
+ }
+ if err != nil {
+ return nil, err
+ }
+ // All WSASocket calls must be match with a syscall.Closesocket call,
+ // but os.NewFile calls syscall.CloseHandle instead. We need to use
+ // a hidden function so that the returned file is aware of this fact.
+ return newWindowsFile(h, fd.name()), nil
+}
diff --git a/go/src/net/file.go b/go/src/net/file.go
new file mode 100644
index 0000000000000000000000000000000000000000..3e33c9afad65845eeb3a85a378d038d42a230c6b
--- /dev/null
+++ b/go/src/net/file.go
@@ -0,0 +1,51 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import "os"
+
+// BUG(mikio): On JS, the FileConn, FileListener and
+// FilePacketConn functions are not implemented.
+
+type fileAddr string
+
+func (fileAddr) Network() string { return "file+net" }
+func (f fileAddr) String() string { return string(f) }
+
+// FileConn returns a copy of the network connection corresponding to
+// the open file f.
+// It is the caller's responsibility to close f when finished.
+// Closing c does not affect f, and closing f does not affect c.
+func FileConn(f *os.File) (c Conn, err error) {
+ c, err = fileConn(f)
+ if err != nil {
+ err = &OpError{Op: "file", Net: "file+net", Source: nil, Addr: fileAddr(f.Name()), Err: err}
+ }
+ return
+}
+
+// FileListener returns a copy of the network listener corresponding
+// to the open file f.
+// It is the caller's responsibility to close ln when finished.
+// Closing ln does not affect f, and closing f does not affect ln.
+func FileListener(f *os.File) (ln Listener, err error) {
+ ln, err = fileListener(f)
+ if err != nil {
+ err = &OpError{Op: "file", Net: "file+net", Source: nil, Addr: fileAddr(f.Name()), Err: err}
+ }
+ return
+}
+
+// FilePacketConn returns a copy of the packet network connection
+// corresponding to the open file f.
+// It is the caller's responsibility to close f when finished.
+// Closing c does not affect f, and closing f does not affect c.
+func FilePacketConn(f *os.File) (c PacketConn, err error) {
+ c, err = filePacketConn(f)
+ if err != nil {
+ err = &OpError{Op: "file", Net: "file+net", Source: nil, Addr: fileAddr(f.Name()), Err: err}
+ }
+ return
+}
diff --git a/go/src/net/file_plan9.go b/go/src/net/file_plan9.go
new file mode 100644
index 0000000000000000000000000000000000000000..6c2151c4098a8af643db8a41e6a47e84ad33a691
--- /dev/null
+++ b/go/src/net/file_plan9.go
@@ -0,0 +1,135 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "errors"
+ "io"
+ "os"
+ "syscall"
+)
+
+func (fd *netFD) status(ln int) (string, error) {
+ if !fd.ok() {
+ return "", syscall.EINVAL
+ }
+
+ status, err := os.Open(fd.dir + "/status")
+ if err != nil {
+ return "", err
+ }
+ defer status.Close()
+ buf := make([]byte, ln)
+ n, err := io.ReadFull(status, buf[:])
+ if err != nil {
+ return "", err
+ }
+ return string(buf[:n]), nil
+}
+
+func newFileFD(f *os.File) (net *netFD, err error) {
+ var ctl *os.File
+ close := func(fd int) {
+ if err != nil {
+ syscall.Close(fd)
+ }
+ }
+
+ path, err := syscall.Fd2path(int(f.Fd()))
+ if err != nil {
+ return nil, os.NewSyscallError("fd2path", err)
+ }
+ comp := splitAtBytes(path, "/")
+ n := len(comp)
+ if n < 3 || comp[0][0:3] != "net" {
+ return nil, syscall.EPLAN9
+ }
+
+ name := comp[2]
+ switch file := comp[n-1]; file {
+ case "ctl", "clone":
+ fd, err := syscall.Dup(int(f.Fd()), -1)
+ if err != nil {
+ return nil, os.NewSyscallError("dup", err)
+ }
+ defer close(fd)
+
+ dir := netdir + "/" + comp[n-2]
+ ctl = os.NewFile(uintptr(fd), dir+"/"+file)
+ ctl.Seek(0, io.SeekStart)
+ var buf [16]byte
+ n, err := ctl.Read(buf[:])
+ if err != nil {
+ return nil, err
+ }
+ name = string(buf[:n])
+ default:
+ if len(comp) < 4 {
+ return nil, errors.New("could not find control file for connection")
+ }
+ dir := netdir + "/" + comp[1] + "/" + name
+ ctl, err = os.OpenFile(dir+"/ctl", os.O_RDWR, 0)
+ if err != nil {
+ return nil, err
+ }
+ defer close(int(ctl.Fd()))
+ }
+ dir := netdir + "/" + comp[1] + "/" + name
+ laddr, err := readPlan9Addr(comp[1], dir+"/local")
+ if err != nil {
+ return nil, err
+ }
+ return newFD(comp[1], name, nil, ctl, nil, laddr, nil)
+}
+
+func fileConn(f *os.File) (Conn, error) {
+ fd, err := newFileFD(f)
+ if err != nil {
+ return nil, err
+ }
+ if !fd.ok() {
+ return nil, syscall.EINVAL
+ }
+
+ fd.data, err = os.OpenFile(fd.dir+"/data", os.O_RDWR, 0)
+ if err != nil {
+ return nil, err
+ }
+
+ switch fd.laddr.(type) {
+ case *TCPAddr:
+ return newTCPConn(fd, defaultTCPKeepAliveIdle, KeepAliveConfig{}, testPreHookSetKeepAlive, testHookSetKeepAlive), nil
+ case *UDPAddr:
+ return newUDPConn(fd), nil
+ }
+ return nil, syscall.EPLAN9
+}
+
+func fileListener(f *os.File) (Listener, error) {
+ fd, err := newFileFD(f)
+ if err != nil {
+ return nil, err
+ }
+ switch fd.laddr.(type) {
+ case *TCPAddr:
+ default:
+ return nil, syscall.EPLAN9
+ }
+
+ // check that file corresponds to a listener
+ s, err := fd.status(len("Listen"))
+ if err != nil {
+ return nil, err
+ }
+ if s != "Listen" {
+ return nil, errors.New("file does not represent a listener")
+ }
+
+ return &TCPListener{fd: fd}, nil
+}
+
+func filePacketConn(f *os.File) (PacketConn, error) {
+ return nil, syscall.EPLAN9
+}
diff --git a/go/src/net/file_posix.go b/go/src/net/file_posix.go
new file mode 100644
index 0000000000000000000000000000000000000000..b28ff5845d70d1ee1ab0805a880d1bd73d154551
--- /dev/null
+++ b/go/src/net/file_posix.go
@@ -0,0 +1,108 @@
+// Copyright 2025 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || windows
+
+package net
+
+import (
+ "internal/poll"
+ "os"
+ "syscall"
+)
+
+func newFileFD(f *os.File) (*netFD, error) {
+ s, err := dupFileSocket(f)
+ if err != nil {
+ return nil, err
+ }
+ family := syscall.AF_UNSPEC
+ sotype, err := syscall.GetsockoptInt(s, syscall.SOL_SOCKET, _SO_TYPE)
+ if err != nil {
+ poll.CloseFunc(s)
+ return nil, os.NewSyscallError("getsockopt", err)
+ }
+ lsa, err := syscall.Getsockname(s)
+ if err != nil {
+ poll.CloseFunc(s)
+ return nil, os.NewSyscallError("getsockname", err)
+ }
+ rsa, _ := syscall.Getpeername(s)
+ switch lsa.(type) {
+ case *syscall.SockaddrInet4:
+ family = syscall.AF_INET
+ case *syscall.SockaddrInet6:
+ family = syscall.AF_INET6
+ case *syscall.SockaddrUnix:
+ family = syscall.AF_UNIX
+ default:
+ poll.CloseFunc(s)
+ return nil, syscall.EPROTONOSUPPORT
+ }
+ fd, err := newFD(s, family, sotype, "")
+ if err != nil {
+ poll.CloseFunc(s)
+ return nil, err
+ }
+ laddr := fd.addrFunc()(lsa)
+ raddr := fd.addrFunc()(rsa)
+ fd.net = laddr.Network()
+ if err := fd.init(); err != nil {
+ fd.Close()
+ return nil, err
+ }
+ fd.setAddr(laddr, raddr)
+ return fd, nil
+}
+
+func fileConn(f *os.File) (Conn, error) {
+ fd, err := newFileFD(f)
+ if err != nil {
+ return nil, err
+ }
+ switch fd.laddr.(type) {
+ case *TCPAddr:
+ return newTCPConn(fd, defaultTCPKeepAliveIdle, KeepAliveConfig{}, testPreHookSetKeepAlive, testHookSetKeepAlive), nil
+ case *UDPAddr:
+ return newUDPConn(fd), nil
+ case *IPAddr:
+ return newIPConn(fd), nil
+ case *UnixAddr:
+ return newUnixConn(fd), nil
+ }
+ fd.Close()
+ return nil, syscall.EINVAL
+}
+
+func fileListener(f *os.File) (Listener, error) {
+ fd, err := newFileFD(f)
+ if err != nil {
+ return nil, err
+ }
+ switch laddr := fd.laddr.(type) {
+ case *TCPAddr:
+ return &TCPListener{fd: fd}, nil
+ case *UnixAddr:
+ return &UnixListener{fd: fd, path: laddr.Name, unlink: false}, nil
+ }
+ fd.Close()
+ return nil, syscall.EINVAL
+}
+
+func filePacketConn(f *os.File) (PacketConn, error) {
+ fd, err := newFileFD(f)
+ if err != nil {
+ return nil, err
+ }
+ switch fd.laddr.(type) {
+ case *UDPAddr:
+ return newUDPConn(fd), nil
+ case *IPAddr:
+ return newIPConn(fd), nil
+ case *UnixAddr:
+ return newUnixConn(fd), nil
+ }
+ fd.Close()
+ return nil, syscall.EINVAL
+}
diff --git a/go/src/net/file_stub.go b/go/src/net/file_stub.go
new file mode 100644
index 0000000000000000000000000000000000000000..6fd3eec48d9c09f4fe2802bd70cc09b61580de8a
--- /dev/null
+++ b/go/src/net/file_stub.go
@@ -0,0 +1,16 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build js
+
+package net
+
+import (
+ "os"
+ "syscall"
+)
+
+func fileConn(f *os.File) (Conn, error) { return nil, syscall.ENOPROTOOPT }
+func fileListener(f *os.File) (Listener, error) { return nil, syscall.ENOPROTOOPT }
+func filePacketConn(f *os.File) (PacketConn, error) { return nil, syscall.ENOPROTOOPT }
diff --git a/go/src/net/file_test.go b/go/src/net/file_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..51e54ff506bd1f6a9e2f427abfd63e3f19bb6163
--- /dev/null
+++ b/go/src/net/file_test.go
@@ -0,0 +1,341 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "os"
+ "reflect"
+ "runtime"
+ "sync"
+ "testing"
+)
+
+// The full stack test cases for IPConn have been moved to the
+// following:
+// golang.org/x/net/ipv4
+// golang.org/x/net/ipv6
+// golang.org/x/net/icmp
+
+var fileConnTests = []struct {
+ network string
+}{
+ {"tcp"},
+ {"udp"},
+ {"unix"},
+ {"unixpacket"},
+}
+
+func TestFileConn(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9", "js", "wasip1":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+
+ for _, tt := range fileConnTests {
+ t.Run(tt.network, func(t *testing.T) {
+ if !testableNetwork(tt.network) {
+ t.Skipf("skipping %s test", tt.network)
+ }
+
+ var network, address string
+ switch tt.network {
+ case "udp":
+ c := newLocalPacketListener(t, tt.network)
+ defer c.Close()
+ network = c.LocalAddr().Network()
+ address = c.LocalAddr().String()
+ default:
+ handler := func(ls *localServer, ln Listener) {
+ c, err := ln.Accept()
+ if err != nil {
+ return
+ }
+ defer c.Close()
+ var b [1]byte
+ c.Read(b[:])
+ }
+ ls := newLocalServer(t, tt.network)
+ defer ls.teardown()
+ if err := ls.buildup(handler); err != nil {
+ t.Fatal(err)
+ }
+ network = ls.Listener.Addr().Network()
+ address = ls.Listener.Addr().String()
+ }
+
+ c1, err := Dial(network, address)
+ if err != nil {
+ if perr := parseDialError(err); perr != nil {
+ t.Error(perr)
+ }
+ t.Fatal(err)
+ }
+ addr := c1.LocalAddr()
+
+ var f *os.File
+ switch c1 := c1.(type) {
+ case *TCPConn:
+ f, err = c1.File()
+ case *UDPConn:
+ f, err = c1.File()
+ case *UnixConn:
+ f, err = c1.File()
+ }
+ if err := c1.Close(); err != nil {
+ if perr := parseCloseError(err, false); perr != nil {
+ t.Error(perr)
+ }
+ t.Error(err)
+ }
+ if err != nil {
+ if perr := parseCommonError(err); perr != nil {
+ t.Error(perr)
+ }
+ t.Fatal(err)
+ }
+
+ c2, err := FileConn(f)
+ if err := f.Close(); err != nil {
+ t.Error(err)
+ }
+ if err != nil {
+ if perr := parseCommonError(err); perr != nil {
+ t.Error(perr)
+ }
+ t.Fatal(err)
+ }
+ defer c2.Close()
+
+ if _, err := c2.Write([]byte("FILECONN TEST")); err != nil {
+ if perr := parseWriteError(err); perr != nil {
+ t.Error(perr)
+ }
+ t.Fatal(err)
+ }
+ if !reflect.DeepEqual(c2.LocalAddr(), addr) {
+ t.Fatalf("got %#v; want %#v", c2.LocalAddr(), addr)
+ }
+ })
+ }
+}
+
+var fileListenerTests = []struct {
+ network string
+}{
+ {"tcp"},
+ {"unix"},
+ {"unixpacket"},
+}
+
+func TestFileListener(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9", "js", "wasip1":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+
+ for _, tt := range fileListenerTests {
+ t.Run(tt.network, func(t *testing.T) {
+ if !testableNetwork(tt.network) {
+ t.Skipf("skipping %s test", tt.network)
+ }
+
+ ln1 := newLocalListener(t, tt.network)
+ switch tt.network {
+ case "unix", "unixpacket":
+ defer os.Remove(ln1.Addr().String())
+ }
+ addr := ln1.Addr()
+
+ var (
+ f *os.File
+ err error
+ )
+ switch ln1 := ln1.(type) {
+ case *TCPListener:
+ f, err = ln1.File()
+ case *UnixListener:
+ f, err = ln1.File()
+ }
+ switch tt.network {
+ case "unix", "unixpacket":
+ defer ln1.Close() // UnixListener.Close calls syscall.Unlink internally
+ default:
+ if err := ln1.Close(); err != nil {
+ t.Error(err)
+ }
+ }
+ if err != nil {
+ if perr := parseCommonError(err); perr != nil {
+ t.Error(perr)
+ }
+ t.Fatal(err)
+ }
+
+ ln2, err := FileListener(f)
+ if err := f.Close(); err != nil {
+ t.Error(err)
+ }
+ if err != nil {
+ if perr := parseCommonError(err); perr != nil {
+ t.Error(perr)
+ }
+ t.Fatal(err)
+ }
+ defer ln2.Close()
+
+ var wg sync.WaitGroup
+ wg.Add(1)
+ go func() {
+ defer wg.Done()
+ c, err := Dial(ln2.Addr().Network(), ln2.Addr().String())
+ if err != nil {
+ if perr := parseDialError(err); perr != nil {
+ t.Error(perr)
+ }
+ t.Error(err)
+ return
+ }
+ c.Close()
+ }()
+ c, err := ln2.Accept()
+ if err != nil {
+ if perr := parseAcceptError(err); perr != nil {
+ t.Error(perr)
+ }
+ t.Fatal(err)
+ }
+ c.Close()
+ wg.Wait()
+ if !reflect.DeepEqual(ln2.Addr(), addr) {
+ t.Fatalf("got %#v; want %#v", ln2.Addr(), addr)
+ }
+ })
+ }
+}
+
+var filePacketConnTests = []struct {
+ network string
+}{
+ {"udp"},
+ {"unixgram"},
+}
+
+func TestFilePacketConn(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9", "js", "wasip1":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+
+ for _, tt := range filePacketConnTests {
+ t.Run(tt.network, func(t *testing.T) {
+ if !testableNetwork(tt.network) {
+ t.Skipf("skipping %s test", tt.network)
+ }
+
+ c1 := newLocalPacketListener(t, tt.network)
+ switch tt.network {
+ case "unixgram":
+ defer os.Remove(c1.LocalAddr().String())
+ }
+ addr := c1.LocalAddr()
+
+ var (
+ f *os.File
+ err error
+ )
+ switch c1 := c1.(type) {
+ case *UDPConn:
+ f, err = c1.File()
+ case *UnixConn:
+ f, err = c1.File()
+ }
+ if err := c1.Close(); err != nil {
+ if perr := parseCloseError(err, false); perr != nil {
+ t.Error(perr)
+ }
+ t.Error(err)
+ }
+ if err != nil {
+ if perr := parseCommonError(err); perr != nil {
+ t.Error(perr)
+ }
+ t.Fatal(err)
+ }
+
+ c2, err := FilePacketConn(f)
+ if err := f.Close(); err != nil {
+ t.Error(err)
+ }
+ if err != nil {
+ if perr := parseCommonError(err); perr != nil {
+ t.Error(perr)
+ }
+ t.Fatal(err)
+ }
+ defer c2.Close()
+
+ if _, err := c2.WriteTo([]byte("FILEPACKETCONN TEST"), addr); err != nil {
+ if perr := parseWriteError(err); perr != nil {
+ t.Error(perr)
+ }
+ t.Fatal(err)
+ }
+ if !reflect.DeepEqual(c2.LocalAddr(), addr) {
+ t.Fatalf("got %#v; want %#v", c2.LocalAddr(), addr)
+ }
+ })
+ }
+}
+
+// Issue 24483.
+func TestFileCloseRace(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9", "js", "wasip1":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+ if !testableNetwork("tcp") {
+ t.Skip("tcp not supported")
+ }
+
+ handler := func(ls *localServer, ln Listener) {
+ c, err := ln.Accept()
+ if err != nil {
+ return
+ }
+ defer c.Close()
+ var b [1]byte
+ c.Read(b[:])
+ }
+
+ ls := newLocalServer(t, "tcp")
+ defer ls.teardown()
+ if err := ls.buildup(handler); err != nil {
+ t.Fatal(err)
+ }
+
+ const tries = 100
+ for i := 0; i < tries; i++ {
+ c1, err := Dial(ls.Listener.Addr().Network(), ls.Listener.Addr().String())
+ if err != nil {
+ t.Fatal(err)
+ }
+ tc := c1.(*TCPConn)
+
+ var wg sync.WaitGroup
+ wg.Add(2)
+ go func() {
+ defer wg.Done()
+ f, err := tc.File()
+ if err == nil {
+ f.Close()
+ }
+ }()
+ go func() {
+ defer wg.Done()
+ c1.Close()
+ }()
+ wg.Wait()
+ }
+}
diff --git a/go/src/net/file_unix.go b/go/src/net/file_unix.go
new file mode 100644
index 0000000000000000000000000000000000000000..d56da9003747ab0f94b10b175ec5719a7d5fe8df
--- /dev/null
+++ b/go/src/net/file_unix.go
@@ -0,0 +1,30 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+package net
+
+import (
+ "internal/poll"
+ "os"
+ "syscall"
+)
+
+const _SO_TYPE = syscall.SO_TYPE
+
+func dupFileSocket(f *os.File) (int, error) {
+ s, call, err := poll.DupCloseOnExec(int(f.Fd()))
+ if err != nil {
+ if call != "" {
+ err = os.NewSyscallError(call, err)
+ }
+ return -1, err
+ }
+ if err := syscall.SetNonblock(s, true); err != nil {
+ poll.CloseFunc(s)
+ return -1, os.NewSyscallError("setnonblock", err)
+ }
+ return s, nil
+}
diff --git a/go/src/net/file_unix_test.go b/go/src/net/file_unix_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..0499a02404a3ac7cd2fd1521dd04e29d6a4cc068
--- /dev/null
+++ b/go/src/net/file_unix_test.go
@@ -0,0 +1,101 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+package net
+
+import (
+ "internal/syscall/unix"
+ "testing"
+)
+
+// For backward compatibility, opening a net.Conn, turning it into an os.File,
+// and calling the Fd method should return a blocking descriptor.
+func TestFileFdBlocks(t *testing.T) {
+ if !testableNetwork("unix") {
+ t.Skipf("skipping: unix sockets not supported")
+ }
+
+ ls := newLocalServer(t, "unix")
+ defer ls.teardown()
+
+ errc := make(chan error, 1)
+ done := make(chan bool)
+ handler := func(ls *localServer, ln Listener) {
+ server, err := ln.Accept()
+ errc <- err
+ if err != nil {
+ return
+ }
+ defer server.Close()
+ <-done
+ }
+ if err := ls.buildup(handler); err != nil {
+ t.Fatal(err)
+ }
+ defer close(done)
+
+ client, err := Dial(ls.Listener.Addr().Network(), ls.Listener.Addr().String())
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer client.Close()
+
+ if err := <-errc; err != nil {
+ t.Fatalf("server error: %v", err)
+ }
+
+ // The socket should be non-blocking.
+ rawconn, err := client.(*UnixConn).SyscallConn()
+ if err != nil {
+ t.Fatal(err)
+ }
+ err = rawconn.Control(func(fd uintptr) {
+ nonblock, err := unix.IsNonblock(int(fd))
+ if err != nil {
+ t.Fatal(err)
+ }
+ if !nonblock {
+ t.Fatal("unix socket is in blocking mode")
+ }
+ })
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ file, err := client.(*UnixConn).File()
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ // At this point the descriptor should still be non-blocking.
+ rawconn, err = file.SyscallConn()
+ if err != nil {
+ t.Fatal(err)
+ }
+ err = rawconn.Control(func(fd uintptr) {
+ nonblock, err := unix.IsNonblock(int(fd))
+ if err != nil {
+ t.Fatal(err)
+ }
+ if !nonblock {
+ t.Fatal("unix socket as os.File is in blocking mode")
+ }
+ })
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ fd := file.Fd()
+
+ // Calling Fd should have put the descriptor into blocking mode.
+ nonblock, err := unix.IsNonblock(int(fd))
+ if err != nil {
+ t.Fatal(err)
+ }
+ if nonblock {
+ t.Error("unix socket through os.File.Fd is non-blocking")
+ }
+}
diff --git a/go/src/net/file_wasip1.go b/go/src/net/file_wasip1.go
new file mode 100644
index 0000000000000000000000000000000000000000..a3624efb55e4ba904ee1806c7092957fa96beb2d
--- /dev/null
+++ b/go/src/net/file_wasip1.go
@@ -0,0 +1,102 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build wasip1
+
+package net
+
+import (
+ "os"
+ "syscall"
+ _ "unsafe" // for go:linkname
+)
+
+func fileListener(f *os.File) (Listener, error) {
+ filetype, err := fd_fdstat_get_type(f.PollFD().Sysfd)
+ if err != nil {
+ return nil, err
+ }
+ net, err := fileListenNet(filetype)
+ if err != nil {
+ return nil, err
+ }
+ pfd := f.PollFD().Copy()
+ fd := newPollFD(net, pfd)
+ if err := fd.init(); err != nil {
+ pfd.Close()
+ return nil, err
+ }
+ return newFileListener(fd), nil
+}
+
+func fileConn(f *os.File) (Conn, error) {
+ filetype, err := fd_fdstat_get_type(f.PollFD().Sysfd)
+ if err != nil {
+ return nil, err
+ }
+ net, err := fileConnNet(filetype)
+ if err != nil {
+ return nil, err
+ }
+ pfd := f.PollFD().Copy()
+ fd := newPollFD(net, pfd)
+ if err := fd.init(); err != nil {
+ pfd.Close()
+ return nil, err
+ }
+ return newFileConn(fd), nil
+}
+
+func filePacketConn(f *os.File) (PacketConn, error) {
+ return nil, syscall.ENOPROTOOPT
+}
+
+func fileListenNet(filetype syscall.Filetype) (string, error) {
+ switch filetype {
+ case syscall.FILETYPE_SOCKET_STREAM:
+ return "tcp", nil
+ case syscall.FILETYPE_SOCKET_DGRAM:
+ return "", syscall.EOPNOTSUPP
+ default:
+ return "", syscall.ENOTSOCK
+ }
+}
+
+func fileConnNet(filetype syscall.Filetype) (string, error) {
+ switch filetype {
+ case syscall.FILETYPE_SOCKET_STREAM:
+ return "tcp", nil
+ case syscall.FILETYPE_SOCKET_DGRAM:
+ return "udp", nil
+ default:
+ return "", syscall.ENOTSOCK
+ }
+}
+
+func newFileListener(fd *netFD) Listener {
+ switch fd.net {
+ case "tcp":
+ return &TCPListener{fd: fd}
+ default:
+ panic("unsupported network for file listener: " + fd.net)
+ }
+}
+
+func newFileConn(fd *netFD) Conn {
+ switch fd.net {
+ case "tcp":
+ return &TCPConn{conn{fd: fd}}
+ case "udp":
+ return &UDPConn{conn{fd: fd}}
+ default:
+ panic("unsupported network for file connection: " + fd.net)
+ }
+}
+
+// This helper is implemented in the syscall package. It means we don't have
+// to redefine the fd_fdstat_get host import or the fdstat struct it
+// populates.
+//
+//go:linkname fd_fdstat_get_type syscall.fd_fdstat_get_type
+func fd_fdstat_get_type(fd int) (uint8, error)
diff --git a/go/src/net/file_wasip1_test.go b/go/src/net/file_wasip1_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..91f57eecdacf6ea5d32853a1bacb33cf6b63b70e
--- /dev/null
+++ b/go/src/net/file_wasip1_test.go
@@ -0,0 +1,112 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build wasip1
+
+package net
+
+import (
+ "syscall"
+ "testing"
+)
+
+// The tests in this file intend to validate the ability for net.FileConn and
+// net.FileListener to handle both TCP and UDP sockets. Ideally we would test
+// the public interface by constructing an *os.File from a file descriptor
+// opened on a socket, but the WASI preview 1 specification is too limited to
+// support this approach for UDP sockets. Instead, we test the internals that
+// make it possible for WASI host runtimes and guest programs to integrate
+// socket extensions with the net package using net.FileConn/net.FileListener.
+//
+// Note that the creation of net.Conn and net.Listener values for TCP sockets
+// has an end-to-end test in src/internal/runtime/wasitest, here we are only
+// verifying the code paths specific to UDP, and error handling for invalid use
+// of the functions.
+
+func TestWasip1FileConnNet(t *testing.T) {
+ tests := []struct {
+ filetype syscall.Filetype
+ network string
+ error error
+ }{
+ {syscall.FILETYPE_SOCKET_STREAM, "tcp", nil},
+ {syscall.FILETYPE_SOCKET_DGRAM, "udp", nil},
+ {syscall.FILETYPE_BLOCK_DEVICE, "", syscall.ENOTSOCK},
+ {syscall.FILETYPE_CHARACTER_DEVICE, "", syscall.ENOTSOCK},
+ {syscall.FILETYPE_DIRECTORY, "", syscall.ENOTSOCK},
+ {syscall.FILETYPE_REGULAR_FILE, "", syscall.ENOTSOCK},
+ {syscall.FILETYPE_SYMBOLIC_LINK, "", syscall.ENOTSOCK},
+ {syscall.FILETYPE_UNKNOWN, "", syscall.ENOTSOCK},
+ }
+ for _, test := range tests {
+ net, err := fileConnNet(test.filetype)
+ if net != test.network {
+ t.Errorf("fileConnNet: network mismatch: want=%q got=%q", test.network, net)
+ }
+ if err != test.error {
+ t.Errorf("fileConnNet: error mismatch: want=%v got=%v", test.error, err)
+ }
+ }
+}
+
+func TestWasip1FileListenNet(t *testing.T) {
+ tests := []struct {
+ filetype syscall.Filetype
+ network string
+ error error
+ }{
+ {syscall.FILETYPE_SOCKET_STREAM, "tcp", nil},
+ {syscall.FILETYPE_SOCKET_DGRAM, "", syscall.EOPNOTSUPP},
+ {syscall.FILETYPE_BLOCK_DEVICE, "", syscall.ENOTSOCK},
+ {syscall.FILETYPE_CHARACTER_DEVICE, "", syscall.ENOTSOCK},
+ {syscall.FILETYPE_DIRECTORY, "", syscall.ENOTSOCK},
+ {syscall.FILETYPE_REGULAR_FILE, "", syscall.ENOTSOCK},
+ {syscall.FILETYPE_SYMBOLIC_LINK, "", syscall.ENOTSOCK},
+ {syscall.FILETYPE_UNKNOWN, "", syscall.ENOTSOCK},
+ }
+ for _, test := range tests {
+ net, err := fileListenNet(test.filetype)
+ if net != test.network {
+ t.Errorf("fileListenNet: network mismatch: want=%q got=%q", test.network, net)
+ }
+ if err != test.error {
+ t.Errorf("fileListenNet: error mismatch: want=%v got=%v", test.error, err)
+ }
+ }
+}
+
+func TestWasip1NewFileListener(t *testing.T) {
+ if l, ok := newFileListener(newFD("tcp", -1)).(*TCPListener); !ok {
+ t.Errorf("newFileListener: tcp listener type mismatch: %T", l)
+ } else {
+ testIsTCPAddr(t, "Addr", l.Addr())
+ }
+}
+
+func TestWasip1NewFileConn(t *testing.T) {
+ if c, ok := newFileConn(newFD("tcp", -1)).(*TCPConn); !ok {
+ t.Errorf("newFileConn: tcp conn type mismatch: %T", c)
+ } else {
+ testIsTCPAddr(t, "LocalAddr", c.LocalAddr())
+ testIsTCPAddr(t, "RemoteAddr", c.RemoteAddr())
+ }
+ if c, ok := newFileConn(newFD("udp", -1)).(*UDPConn); !ok {
+ t.Errorf("newFileConn: udp conn type mismatch: %T", c)
+ } else {
+ testIsUDPAddr(t, "LocalAddr", c.LocalAddr())
+ testIsUDPAddr(t, "RemoteAddr", c.RemoteAddr())
+ }
+}
+
+func testIsTCPAddr(t *testing.T, method string, addr Addr) {
+ if _, ok := addr.(*TCPAddr); !ok {
+ t.Errorf("%s: returned address is not a *TCPAddr: %T", method, addr)
+ }
+}
+
+func testIsUDPAddr(t *testing.T, method string, addr Addr) {
+ if _, ok := addr.(*UDPAddr); !ok {
+ t.Errorf("%s: returned address is not a *UDPAddr: %T", method, addr)
+ }
+}
diff --git a/go/src/net/file_windows.go b/go/src/net/file_windows.go
new file mode 100644
index 0000000000000000000000000000000000000000..6a6305035a151aae3c9da9c7cd14beaa9051bcd0
--- /dev/null
+++ b/go/src/net/file_windows.go
@@ -0,0 +1,49 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "internal/syscall/windows"
+ "os"
+ "syscall"
+)
+
+const _SO_TYPE = windows.SO_TYPE
+
+func dupSocket(h syscall.Handle) (syscall.Handle, error) {
+ var info syscall.WSAProtocolInfo
+ err := windows.WSADuplicateSocket(h, uint32(syscall.Getpid()), &info)
+ if err != nil {
+ return 0, err
+ }
+ return windows.WSASocket(-1, -1, -1, &info, 0, windows.WSA_FLAG_OVERLAPPED|windows.WSA_FLAG_NO_HANDLE_INHERIT)
+}
+
+func dupFileSocket(f *os.File) (syscall.Handle, error) {
+ // Call Fd to disassociate the IOCP from the handle,
+ // it is not safe to share a duplicated handle
+ // that is associated with IOCP.
+ // Don't use the returned fd, as it might be closed
+ // if f happens to be the last reference to the file.
+ f.Fd()
+
+ sc, err := f.SyscallConn()
+ if err != nil {
+ return 0, err
+ }
+
+ var h syscall.Handle
+ var syserr error
+ err = sc.Control(func(fd uintptr) {
+ h, syserr = dupSocket(syscall.Handle(fd))
+ })
+ if err == nil {
+ err = syserr
+ }
+ if err != nil {
+ return 0, err
+ }
+ return h, nil
+}
diff --git a/go/src/net/hook.go b/go/src/net/hook.go
new file mode 100644
index 0000000000000000000000000000000000000000..08d1aa893481f2003f8ea61352ee632742c5288e
--- /dev/null
+++ b/go/src/net/hook.go
@@ -0,0 +1,31 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "context"
+)
+
+var (
+ // if non-nil, overrides dialTCP.
+ testHookDialTCP func(ctx context.Context, net string, laddr, raddr *TCPAddr) (*TCPConn, error)
+
+ testHookLookupIP = func(
+ ctx context.Context,
+ fn func(context.Context, string, string) ([]IPAddr, error),
+ network string,
+ host string,
+ ) ([]IPAddr, error) {
+ return fn(ctx, network, host)
+ }
+ testPreHookSetKeepAlive = func(*netFD) {}
+ testHookSetKeepAlive = func(KeepAliveConfig) {}
+
+ // testHookStepTime sleeps until time has moved forward by a nonzero amount.
+ // This helps to avoid flakes in timeout tests by ensuring that an implausibly
+ // short deadline (such as 1ns in the future) is always expired by the time
+ // a relevant system call occurs.
+ testHookStepTime = func() {}
+)
diff --git a/go/src/net/hook_plan9.go b/go/src/net/hook_plan9.go
new file mode 100644
index 0000000000000000000000000000000000000000..6020d329240272e0933034a59fbb03a8f312908e
--- /dev/null
+++ b/go/src/net/hook_plan9.go
@@ -0,0 +1,9 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+var (
+ hostsFilePath = "/etc/hosts"
+)
diff --git a/go/src/net/hook_unix.go b/go/src/net/hook_unix.go
new file mode 100644
index 0000000000000000000000000000000000000000..69b375598dc6adbd4a071681da67c704ef9fa38a
--- /dev/null
+++ b/go/src/net/hook_unix.go
@@ -0,0 +1,21 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || js || wasip1
+
+package net
+
+import "syscall"
+
+var (
+ testHookCanceledDial = func() {} // for golang.org/issue/16523
+
+ hostsFilePath = "/etc/hosts"
+
+ // Placeholders for socket system calls.
+ socketFunc func(int, int, int) (int, error) = syscall.Socket
+ connectFunc func(int, syscall.Sockaddr) error = syscall.Connect
+ listenFunc func(int, int) error = syscall.Listen
+ getsockoptIntFunc func(int, int, int) (int, error) = syscall.GetsockoptInt
+)
diff --git a/go/src/net/hook_windows.go b/go/src/net/hook_windows.go
new file mode 100644
index 0000000000000000000000000000000000000000..f7c5b5af90fe354f9d4238dade86aa0e08481e35
--- /dev/null
+++ b/go/src/net/hook_windows.go
@@ -0,0 +1,19 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "internal/syscall/windows"
+ "syscall"
+)
+
+var (
+ hostsFilePath = windows.GetSystemDirectory() + "/Drivers/etc/hosts"
+
+ // Placeholders for socket system calls.
+ wsaSocketFunc func(int32, int32, int32, *syscall.WSAProtocolInfo, uint32, uint32) (syscall.Handle, error) = windows.WSASocket
+ connectFunc func(syscall.Handle, syscall.Sockaddr) error = syscall.Connect
+ listenFunc func(syscall.Handle, int) error = syscall.Listen
+)
diff --git a/go/src/net/hosts.go b/go/src/net/hosts.go
new file mode 100644
index 0000000000000000000000000000000000000000..73e6fcc7a4ae7dfbab02a44d6b4fb0e531beb8c9
--- /dev/null
+++ b/go/src/net/hosts.go
@@ -0,0 +1,165 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "errors"
+ "internal/bytealg"
+ "io/fs"
+ "net/netip"
+ "sync"
+ "time"
+)
+
+const cacheMaxAge = 5 * time.Second
+
+func parseLiteralIP(addr string) string {
+ ip, err := netip.ParseAddr(addr)
+ if err != nil {
+ return ""
+ }
+ return ip.String()
+}
+
+type byName struct {
+ addrs []string
+ canonicalName string
+}
+
+// hosts contains known host entries.
+var hosts struct {
+ sync.Mutex
+
+ // Key for the list of literal IP addresses must be a host
+ // name. It would be part of DNS labels, a FQDN or an absolute
+ // FQDN.
+ // For now the key is converted to lower case for convenience.
+ byName map[string]byName
+
+ // Key for the list of host names must be a literal IP address
+ // including IPv6 address with zone identifier.
+ // We don't support old-classful IP address notation.
+ byAddr map[string][]string
+
+ expire time.Time
+ path string
+ mtime time.Time
+ size int64
+}
+
+func readHosts() {
+ now := time.Now()
+ hp := hostsFilePath
+
+ if now.Before(hosts.expire) && hosts.path == hp && len(hosts.byName) > 0 {
+ return
+ }
+ mtime, size, err := stat(hp)
+ if err == nil && hosts.path == hp && hosts.mtime.Equal(mtime) && hosts.size == size {
+ hosts.expire = now.Add(cacheMaxAge)
+ return
+ }
+
+ hs := make(map[string]byName)
+ is := make(map[string][]string)
+
+ file, err := open(hp)
+ if err != nil {
+ if !errors.Is(err, fs.ErrNotExist) && !errors.Is(err, fs.ErrPermission) {
+ return
+ }
+ }
+
+ if file != nil {
+ defer file.close()
+ for line, ok := file.readLine(); ok; line, ok = file.readLine() {
+ if i := bytealg.IndexByteString(line, '#'); i >= 0 {
+ // Discard comments.
+ line = line[0:i]
+ }
+ f := getFields(line)
+ if len(f) < 2 {
+ continue
+ }
+ addr := parseLiteralIP(f[0])
+ if addr == "" {
+ continue
+ }
+
+ var canonical string
+ for i := 1; i < len(f); i++ {
+ name := absDomainName(f[i])
+ h := []byte(f[i])
+ lowerASCIIBytes(h)
+ key := absDomainName(string(h))
+
+ if i == 1 {
+ canonical = key
+ }
+
+ is[addr] = append(is[addr], name)
+
+ if v, ok := hs[key]; ok {
+ hs[key] = byName{
+ addrs: append(v.addrs, addr),
+ canonicalName: v.canonicalName,
+ }
+ continue
+ }
+
+ hs[key] = byName{
+ addrs: []string{addr},
+ canonicalName: canonical,
+ }
+ }
+ }
+ }
+ // Update the data cache.
+ hosts.expire = now.Add(cacheMaxAge)
+ hosts.path = hp
+ hosts.byName = hs
+ hosts.byAddr = is
+ hosts.mtime = mtime
+ hosts.size = size
+}
+
+// lookupStaticHost looks up the addresses and the canonical name for the given host from /etc/hosts.
+func lookupStaticHost(host string) ([]string, string) {
+ hosts.Lock()
+ defer hosts.Unlock()
+ readHosts()
+ if len(hosts.byName) != 0 {
+ if hasUpperCase(host) {
+ lowerHost := []byte(host)
+ lowerASCIIBytes(lowerHost)
+ host = string(lowerHost)
+ }
+ if byName, ok := hosts.byName[absDomainName(host)]; ok {
+ ipsCp := make([]string, len(byName.addrs))
+ copy(ipsCp, byName.addrs)
+ return ipsCp, byName.canonicalName
+ }
+ }
+ return nil, ""
+}
+
+// lookupStaticAddr looks up the hosts for the given address from /etc/hosts.
+func lookupStaticAddr(addr string) []string {
+ hosts.Lock()
+ defer hosts.Unlock()
+ readHosts()
+ addr = parseLiteralIP(addr)
+ if addr == "" {
+ return nil
+ }
+ if len(hosts.byAddr) != 0 {
+ if hosts, ok := hosts.byAddr[addr]; ok {
+ hostsCp := make([]string, len(hosts))
+ copy(hostsCp, hosts)
+ return hostsCp
+ }
+ }
+ return nil
+}
diff --git a/go/src/net/hosts_test.go b/go/src/net/hosts_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..2661e79d993d203641b8f4e169ec8e8cbacdd959
--- /dev/null
+++ b/go/src/net/hosts_test.go
@@ -0,0 +1,214 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "slices"
+ "strings"
+ "testing"
+)
+
+type staticHostEntry struct {
+ in string
+ out []string
+}
+
+var lookupStaticHostTests = []struct {
+ name string
+ ents []staticHostEntry
+}{
+ {
+ "testdata/hosts",
+ []staticHostEntry{
+ {"odin", []string{"127.0.0.2", "127.0.0.3", "::2"}},
+ {"thor", []string{"127.1.1.1"}},
+ {"ullr", []string{"127.1.1.2"}},
+ {"ullrhost", []string{"127.1.1.2"}},
+ {"localhost", []string{"fe80::1%lo0"}},
+ },
+ },
+ {
+ "testdata/singleline-hosts", // see golang.org/issue/6646
+ []staticHostEntry{
+ {"odin", []string{"127.0.0.2"}},
+ },
+ },
+ {
+ "testdata/ipv4-hosts",
+ []staticHostEntry{
+ {"localhost", []string{"127.0.0.1", "127.0.0.2", "127.0.0.3"}},
+ {"localhost.localdomain", []string{"127.0.0.3"}},
+ },
+ },
+ {
+ "testdata/ipv6-hosts", // see golang.org/issue/8996
+ []staticHostEntry{
+ {"localhost", []string{"::1", "fe80::1", "fe80::2%lo0", "fe80::3%lo0"}},
+ {"localhost.localdomain", []string{"fe80::3%lo0"}},
+ },
+ },
+ {
+ "testdata/case-hosts", // see golang.org/issue/12806
+ []staticHostEntry{
+ {"PreserveMe", []string{"127.0.0.1", "::1"}},
+ {"PreserveMe.local", []string{"127.0.0.1", "::1"}},
+ },
+ },
+}
+
+func TestLookupStaticHost(t *testing.T) {
+ defer func(orig string) { hostsFilePath = orig }(hostsFilePath)
+
+ for _, tt := range lookupStaticHostTests {
+ hostsFilePath = tt.name
+ for _, ent := range tt.ents {
+ testStaticHost(t, tt.name, ent)
+ }
+ }
+}
+
+func testStaticHost(t *testing.T, hostsPath string, ent staticHostEntry) {
+ ins := []string{ent.in, absDomainName(ent.in), strings.ToLower(ent.in), strings.ToUpper(ent.in)}
+ for _, in := range ins {
+ addrs, _ := lookupStaticHost(in)
+ if !slices.Equal(addrs, ent.out) {
+ t.Errorf("%s, lookupStaticHost(%s) = %v; want %v", hostsPath, in, addrs, ent.out)
+ }
+ }
+}
+
+var lookupStaticAddrTests = []struct {
+ name string
+ ents []staticHostEntry
+}{
+ {
+ "testdata/hosts",
+ []staticHostEntry{
+ {"255.255.255.255", []string{"broadcasthost"}},
+ {"127.0.0.2", []string{"odin"}},
+ {"127.0.0.3", []string{"odin"}},
+ {"::2", []string{"odin"}},
+ {"127.1.1.1", []string{"thor"}},
+ {"127.1.1.2", []string{"ullr", "ullrhost"}},
+ {"fe80::1%lo0", []string{"localhost"}},
+ },
+ },
+ {
+ "testdata/singleline-hosts", // see golang.org/issue/6646
+ []staticHostEntry{
+ {"127.0.0.2", []string{"odin"}},
+ },
+ },
+ {
+ "testdata/ipv4-hosts",
+ []staticHostEntry{
+ {"127.0.0.1", []string{"localhost"}},
+ {"127.0.0.2", []string{"localhost"}},
+ {"127.0.0.3", []string{"localhost", "localhost.localdomain"}},
+ },
+ },
+ {
+ "testdata/ipv6-hosts", // see golang.org/issue/8996
+ []staticHostEntry{
+ {"::1", []string{"localhost"}},
+ {"fe80::1", []string{"localhost"}},
+ {"fe80::2%lo0", []string{"localhost"}},
+ {"fe80::3%lo0", []string{"localhost", "localhost.localdomain"}},
+ },
+ },
+ {
+ "testdata/case-hosts", // see golang.org/issue/12806
+ []staticHostEntry{
+ {"127.0.0.1", []string{"PreserveMe", "PreserveMe.local"}},
+ {"::1", []string{"PreserveMe", "PreserveMe.local"}},
+ },
+ },
+}
+
+func TestLookupStaticAddr(t *testing.T) {
+ defer func(orig string) { hostsFilePath = orig }(hostsFilePath)
+
+ for _, tt := range lookupStaticAddrTests {
+ hostsFilePath = tt.name
+ for _, ent := range tt.ents {
+ testStaticAddr(t, tt.name, ent)
+ }
+ }
+}
+
+func testStaticAddr(t *testing.T, hostsPath string, ent staticHostEntry) {
+ hosts := lookupStaticAddr(ent.in)
+ for i := range ent.out {
+ ent.out[i] = absDomainName(ent.out[i])
+ }
+ if !slices.Equal(hosts, ent.out) {
+ t.Errorf("%s, lookupStaticAddr(%s) = %v; want %v", hostsPath, ent.in, hosts, ent.out)
+ }
+}
+
+func TestHostCacheModification(t *testing.T) {
+ // Ensure that programs can't modify the internals of the host cache.
+ // See https://golang.org/issues/14212.
+ defer func(orig string) { hostsFilePath = orig }(hostsFilePath)
+
+ hostsFilePath = "testdata/ipv4-hosts"
+ ent := staticHostEntry{"localhost", []string{"127.0.0.1", "127.0.0.2", "127.0.0.3"}}
+ testStaticHost(t, hostsFilePath, ent)
+ // Modify the addresses return by lookupStaticHost.
+ addrs, _ := lookupStaticHost(ent.in)
+ for i := range addrs {
+ addrs[i] += "junk"
+ }
+ testStaticHost(t, hostsFilePath, ent)
+
+ hostsFilePath = "testdata/ipv6-hosts"
+ ent = staticHostEntry{"::1", []string{"localhost"}}
+ testStaticAddr(t, hostsFilePath, ent)
+ // Modify the hosts return by lookupStaticAddr.
+ hosts := lookupStaticAddr(ent.in)
+ for i := range hosts {
+ hosts[i] += "junk"
+ }
+ testStaticAddr(t, hostsFilePath, ent)
+}
+
+var lookupStaticHostAliasesTest = []struct {
+ lookup, res string
+}{
+ // 127.0.0.1
+ {"test", "test"},
+ // 127.0.0.2
+ {"test2.example.com", "test2.example.com"},
+ {"2.test", "test2.example.com"},
+ // 127.0.0.3
+ {"test3.example.com", "3.test"},
+ {"3.test", "3.test"},
+ // 127.0.0.4
+ {"example.com", "example.com"},
+ // 127.0.0.5
+ {"test5.example.com", "test4.example.com"},
+ {"5.test", "test4.example.com"},
+ {"4.test", "test4.example.com"},
+ {"test4.example.com", "test4.example.com"},
+}
+
+func TestLookupStaticHostAliases(t *testing.T) {
+ defer func(orig string) { hostsFilePath = orig }(hostsFilePath)
+
+ hostsFilePath = "testdata/aliases"
+ for _, ent := range lookupStaticHostAliasesTest {
+ testLookupStaticHostAliases(t, ent.lookup, absDomainName(ent.res))
+ }
+}
+
+func testLookupStaticHostAliases(t *testing.T, lookup, lookupRes string) {
+ ins := []string{lookup, absDomainName(lookup), strings.ToLower(lookup), strings.ToUpper(lookup)}
+ for _, in := range ins {
+ _, res := lookupStaticHost(in)
+ if res != lookupRes {
+ t.Errorf("lookupStaticHost(%v): got %v, want %v", in, res, lookupRes)
+ }
+ }
+}
diff --git a/go/src/net/interface.go b/go/src/net/interface.go
new file mode 100644
index 0000000000000000000000000000000000000000..3cf52c53713001c9ec8af1078bb5341135c06573
--- /dev/null
+++ b/go/src/net/interface.go
@@ -0,0 +1,262 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "errors"
+ "internal/strconv"
+ "sync"
+ "time"
+ _ "unsafe"
+)
+
+// BUG(mikio): On JS, methods and functions related to
+// Interface are not implemented.
+
+// BUG(mikio): On AIX, DragonFly BSD, NetBSD, OpenBSD, Plan 9 and
+// Solaris, the MulticastAddrs method of Interface is not implemented.
+
+var (
+ errInvalidInterface = errors.New("invalid network interface")
+ errInvalidInterfaceIndex = errors.New("invalid network interface index")
+ errInvalidInterfaceName = errors.New("invalid network interface name")
+ errNoSuchInterface = errors.New("no such network interface")
+ errNoSuchMulticastInterface = errors.New("no such multicast network interface")
+)
+
+// Interface represents a mapping between network interface name
+// and index. It also represents network interface facility
+// information.
+type Interface struct {
+ Index int // positive integer that starts at one, zero is never used
+ MTU int // maximum transmission unit
+ Name string // e.g., "en0", "lo0", "eth0.100"; may be the empty string
+ HardwareAddr HardwareAddr // IEEE MAC-48, EUI-48 and EUI-64 form
+ Flags Flags // e.g., FlagUp, FlagLoopback, FlagMulticast
+}
+
+type Flags uint
+
+const (
+ FlagUp Flags = 1 << iota // interface is administratively up
+ FlagBroadcast // interface supports broadcast access capability
+ FlagLoopback // interface is a loopback interface
+ FlagPointToPoint // interface belongs to a point-to-point link
+ FlagMulticast // interface supports multicast access capability
+ FlagRunning // interface is in running state
+)
+
+var flagNames = []string{
+ "up",
+ "broadcast",
+ "loopback",
+ "pointtopoint",
+ "multicast",
+ "running",
+}
+
+func (f Flags) String() string {
+ s := ""
+ for i, name := range flagNames {
+ if f&(1< 0 {
+ ifm := (*syscall.IfMsgHdr)(unsafe.Pointer(&tab[0]))
+ if ifm.Msglen == 0 {
+ break
+ }
+ if ifm.Type == syscall.RTM_IFINFO {
+ if ifindex == 0 || ifindex == int(ifm.Index) {
+ sdl := (*rawSockaddrDatalink)(unsafe.Pointer(&tab[syscall.SizeofIfMsghdr]))
+
+ ifi := &Interface{Index: int(ifm.Index), Flags: linkFlags(ifm.Flags)}
+ ifi.Name = string(sdl.Data[:sdl.Nlen])
+ ifi.HardwareAddr = sdl.Data[sdl.Nlen : sdl.Nlen+sdl.Alen]
+
+ // Retrieve MTU
+ ifr := &ifreq{}
+ copy(ifr.Name[:], ifi.Name)
+ err = unix.Ioctl(sock, syscall.SIOCGIFMTU, unsafe.Pointer(ifr))
+ if err != nil {
+ return nil, err
+ }
+ ifi.MTU = int(ifr.Ifru[0])<<24 | int(ifr.Ifru[1])<<16 | int(ifr.Ifru[2])<<8 | int(ifr.Ifru[3])
+
+ ift = append(ift, *ifi)
+ if ifindex == int(ifm.Index) {
+ break
+ }
+ }
+ }
+ tab = tab[ifm.Msglen:]
+ }
+
+ return ift, nil
+}
+
+func linkFlags(rawFlags int32) Flags {
+ var f Flags
+ if rawFlags&syscall.IFF_UP != 0 {
+ f |= FlagUp
+ }
+ if rawFlags&syscall.IFF_RUNNING != 0 {
+ f |= FlagRunning
+ }
+ if rawFlags&syscall.IFF_BROADCAST != 0 {
+ f |= FlagBroadcast
+ }
+ if rawFlags&syscall.IFF_LOOPBACK != 0 {
+ f |= FlagLoopback
+ }
+ if rawFlags&syscall.IFF_POINTOPOINT != 0 {
+ f |= FlagPointToPoint
+ }
+ if rawFlags&syscall.IFF_MULTICAST != 0 {
+ f |= FlagMulticast
+ }
+ return f
+}
+
+// If the ifi is nil, interfaceAddrTable returns addresses for all
+// network interfaces. Otherwise it returns addresses for a specific
+// interface.
+func interfaceAddrTable(ifi *Interface) ([]Addr, error) {
+ tab, err := getIfList()
+ if err != nil {
+ return nil, err
+ }
+
+ var ifat []Addr
+ for len(tab) > 0 {
+ ifm := (*syscall.IfMsgHdr)(unsafe.Pointer(&tab[0]))
+ if ifm.Msglen == 0 {
+ break
+ }
+ if ifm.Type == syscall.RTM_NEWADDR {
+ if ifi == nil || ifi.Index == int(ifm.Index) {
+ mask := ifm.Addrs
+ off := uint(syscall.SizeofIfMsghdr)
+
+ var iprsa, nmrsa *syscall.RawSockaddr
+ for i := uint(0); i < _RTAX_MAX; i++ {
+ if mask&(1< 0 {
+ ift[n].HardwareAddr = make([]byte, len(sa.Addr))
+ copy(ift[n].HardwareAddr, sa.Addr)
+ }
+ ift[n].MTU = m.MTU()
+ n++
+ if ifindex == m.Index {
+ return ift[:n], nil
+ }
+ }
+ }
+ return ift[:n], nil
+}
+
+func linkFlags(rawFlags int) Flags {
+ var f Flags
+ if rawFlags&syscall.IFF_UP != 0 {
+ f |= FlagUp
+ }
+ if rawFlags&syscall.IFF_RUNNING != 0 {
+ f |= FlagRunning
+ }
+ if rawFlags&syscall.IFF_BROADCAST != 0 {
+ f |= FlagBroadcast
+ }
+ if rawFlags&syscall.IFF_LOOPBACK != 0 {
+ f |= FlagLoopback
+ }
+ if rawFlags&syscall.IFF_POINTOPOINT != 0 {
+ f |= FlagPointToPoint
+ }
+ if rawFlags&syscall.IFF_MULTICAST != 0 {
+ f |= FlagMulticast
+ }
+ return f
+}
+
+// If the ifi is nil, interfaceAddrTable returns addresses for all
+// network interfaces. Otherwise it returns addresses for a specific
+// interface.
+func interfaceAddrTable(ifi *Interface) ([]Addr, error) {
+ index := 0
+ if ifi != nil {
+ index = ifi.Index
+ }
+ msgs, err := interfaceMessages(index)
+ if err != nil {
+ return nil, err
+ }
+ ifat := make([]Addr, 0, len(msgs))
+ for _, m := range msgs {
+ switch m := m.(type) {
+ case *routebsd.InterfaceAddrMessage:
+ if index != 0 && index != m.Index {
+ continue
+ }
+ var mask IPMask
+ switch sa := m.Addrs[syscall.RTAX_NETMASK].(type) {
+ case *routebsd.InetAddr:
+ if sa.IP.Is4() {
+ a := sa.IP.As4()
+ mask = IPv4Mask(a[0], a[1], a[2], a[3])
+ } else if sa.IP.Is6() {
+ a := sa.IP.As16()
+ mask = make(IPMask, IPv6len)
+ copy(mask, a[:])
+ }
+ }
+ var ip IP
+ switch sa := m.Addrs[syscall.RTAX_IFA].(type) {
+ case *routebsd.InetAddr:
+ if sa.IP.Is4() {
+ a := sa.IP.As4()
+ ip = IPv4(a[0], a[1], a[2], a[3])
+ } else if sa.IP.Is6() {
+ a := sa.IP.As16()
+ ip = make(IP, IPv6len)
+ copy(ip, a[:])
+ }
+ }
+ if ip != nil && mask != nil { // NetBSD may contain routebsd.LinkAddr
+ ifat = append(ifat, &IPNet{IP: ip, Mask: mask})
+ }
+ }
+ }
+ return ifat, nil
+}
diff --git a/go/src/net/interface_bsd_test.go b/go/src/net/interface_bsd_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..ce59962f6108f42e50f4f740b368933dbd420b15
--- /dev/null
+++ b/go/src/net/interface_bsd_test.go
@@ -0,0 +1,60 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build darwin || dragonfly || freebsd || netbsd || openbsd
+
+package net
+
+import (
+ "errors"
+ "fmt"
+ "os/exec"
+ "runtime"
+)
+
+func (ti *testInterface) setBroadcast(vid int) error {
+ if runtime.GOOS == "openbsd" {
+ ti.name = fmt.Sprintf("vether%d", vid)
+ } else {
+ ti.name = fmt.Sprintf("vlan%d", vid)
+ }
+ xname, err := exec.LookPath("ifconfig")
+ if err != nil {
+ return err
+ }
+ ti.setupCmds = append(ti.setupCmds, &exec.Cmd{
+ Path: xname,
+ Args: []string{"ifconfig", ti.name, "create"},
+ })
+ ti.teardownCmds = append(ti.teardownCmds, &exec.Cmd{
+ Path: xname,
+ Args: []string{"ifconfig", ti.name, "destroy"},
+ })
+ return nil
+}
+
+func (ti *testInterface) setPointToPoint(suffix int) error {
+ ti.name = fmt.Sprintf("gif%d", suffix)
+ xname, err := exec.LookPath("ifconfig")
+ if err != nil {
+ return err
+ }
+ ti.setupCmds = append(ti.setupCmds, &exec.Cmd{
+ Path: xname,
+ Args: []string{"ifconfig", ti.name, "create"},
+ })
+ ti.setupCmds = append(ti.setupCmds, &exec.Cmd{
+ Path: xname,
+ Args: []string{"ifconfig", ti.name, "inet", ti.local, ti.remote},
+ })
+ ti.teardownCmds = append(ti.teardownCmds, &exec.Cmd{
+ Path: xname,
+ Args: []string{"ifconfig", ti.name, "destroy"},
+ })
+ return nil
+}
+
+func (ti *testInterface) setLinkLocal(suffix int) error {
+ return errors.New("not yet implemented for BSD")
+}
diff --git a/go/src/net/interface_bsdvar.go b/go/src/net/interface_bsdvar.go
new file mode 100644
index 0000000000000000000000000000000000000000..dc6c293a8e4b1abb4dfbc708eebfcdcc6f9a19c9
--- /dev/null
+++ b/go/src/net/interface_bsdvar.go
@@ -0,0 +1,23 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build dragonfly || netbsd || openbsd
+
+package net
+
+import (
+ "internal/routebsd"
+ "syscall"
+)
+
+func interfaceMessages(ifindex int) ([]routebsd.Message, error) {
+ return routebsd.FetchRIBMessages(syscall.NET_RT_IFLIST, ifindex)
+}
+
+// interfaceMulticastAddrTable returns addresses for a specific
+// interface.
+func interfaceMulticastAddrTable(ifi *Interface) ([]Addr, error) {
+ // TODO(mikio): Implement this like other platforms.
+ return nil, nil
+}
diff --git a/go/src/net/interface_darwin.go b/go/src/net/interface_darwin.go
new file mode 100644
index 0000000000000000000000000000000000000000..95c44e68e63a1ec9d478a38372f2e9d2ff8f8de2
--- /dev/null
+++ b/go/src/net/interface_darwin.go
@@ -0,0 +1,48 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "internal/routebsd"
+ "syscall"
+)
+
+func interfaceMessages(ifindex int) ([]routebsd.Message, error) {
+ return routebsd.FetchRIBMessages(syscall.NET_RT_IFLIST, ifindex)
+}
+
+// interfaceMulticastAddrTable returns addresses for a specific
+// interface.
+func interfaceMulticastAddrTable(ifi *Interface) ([]Addr, error) {
+ msgs, err := routebsd.FetchRIBMessages(syscall.NET_RT_IFLIST2, ifi.Index)
+ if err != nil {
+ return nil, err
+ }
+ ifmat := make([]Addr, 0, len(msgs))
+ for _, m := range msgs {
+ switch m := m.(type) {
+ case *routebsd.InterfaceMulticastAddrMessage:
+ if ifi.Index != m.Index {
+ continue
+ }
+ var ip IP
+ switch sa := m.Addrs[syscall.RTAX_IFA].(type) {
+ case *routebsd.InetAddr:
+ if sa.IP.Is4() {
+ a := sa.IP.As4()
+ ip = IPv4(a[0], a[1], a[2], a[3])
+ } else if sa.IP.Is6() {
+ a := sa.IP.As16()
+ ip = make(IP, IPv6len)
+ copy(ip, a[:])
+ }
+ }
+ if ip != nil {
+ ifmat = append(ifmat, &IPAddr{IP: ip})
+ }
+ }
+ }
+ return ifmat, nil
+}
diff --git a/go/src/net/interface_freebsd.go b/go/src/net/interface_freebsd.go
new file mode 100644
index 0000000000000000000000000000000000000000..301faa47baef791d3768b1254496e6e30683b692
--- /dev/null
+++ b/go/src/net/interface_freebsd.go
@@ -0,0 +1,48 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "internal/routebsd"
+ "syscall"
+)
+
+func interfaceMessages(ifindex int) ([]routebsd.Message, error) {
+ return routebsd.FetchRIBMessages(syscall.NET_RT_IFLIST, ifindex)
+}
+
+// interfaceMulticastAddrTable returns addresses for a specific
+// interface.
+func interfaceMulticastAddrTable(ifi *Interface) ([]Addr, error) {
+ msgs, err := routebsd.FetchRIBMessages(syscall.NET_RT_IFMALIST, ifi.Index)
+ if err != nil {
+ return nil, err
+ }
+ ifmat := make([]Addr, 0, len(msgs))
+ for _, m := range msgs {
+ switch m := m.(type) {
+ case *routebsd.InterfaceMulticastAddrMessage:
+ if ifi.Index != m.Index {
+ continue
+ }
+ var ip IP
+ switch sa := m.Addrs[syscall.RTAX_IFA].(type) {
+ case *routebsd.InetAddr:
+ if sa.IP.Is4() {
+ a := sa.IP.As4()
+ ip = IPv4(a[0], a[1], a[2], a[3])
+ } else if sa.IP.Is6() {
+ a := sa.IP.As16()
+ ip = make(IP, IPv6len)
+ copy(ip, a[:])
+ }
+ }
+ if ip != nil {
+ ifmat = append(ifmat, &IPAddr{IP: ip})
+ }
+ }
+ }
+ return ifmat, nil
+}
diff --git a/go/src/net/interface_linux.go b/go/src/net/interface_linux.go
new file mode 100644
index 0000000000000000000000000000000000000000..7856dae8fc878b72a5444a069b53580498418d63
--- /dev/null
+++ b/go/src/net/interface_linux.go
@@ -0,0 +1,257 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "os"
+ "syscall"
+ "unsafe"
+)
+
+// If the ifindex is zero, interfaceTable returns mappings of all
+// network interfaces. Otherwise it returns a mapping of a specific
+// interface.
+func interfaceTable(ifindex int) ([]Interface, error) {
+ tab, err := syscall.NetlinkRIB(syscall.RTM_GETLINK, syscall.AF_UNSPEC)
+ if err != nil {
+ return nil, os.NewSyscallError("netlinkrib", err)
+ }
+ msgs, err := syscall.ParseNetlinkMessage(tab)
+ if err != nil {
+ return nil, os.NewSyscallError("parsenetlinkmessage", err)
+ }
+ var ift []Interface
+loop:
+ for _, m := range msgs {
+ switch m.Header.Type {
+ case syscall.NLMSG_DONE:
+ break loop
+ case syscall.RTM_NEWLINK:
+ ifim := (*syscall.IfInfomsg)(unsafe.Pointer(&m.Data[0]))
+ if ifindex == 0 || ifindex == int(ifim.Index) {
+ attrs, err := syscall.ParseNetlinkRouteAttr(&m)
+ if err != nil {
+ return nil, os.NewSyscallError("parsenetlinkrouteattr", err)
+ }
+ ift = append(ift, *newLink(ifim, attrs))
+ if ifindex == int(ifim.Index) {
+ break loop
+ }
+ }
+ }
+ }
+ return ift, nil
+}
+
+const (
+ // See linux/if_arp.h.
+ // Note that Linux doesn't support IPv4 over IPv6 tunneling.
+ sysARPHardwareIPv4IPv4 = 768 // IPv4 over IPv4 tunneling
+ sysARPHardwareIPv6IPv6 = 769 // IPv6 over IPv6 tunneling
+ sysARPHardwareIPv6IPv4 = 776 // IPv6 over IPv4 tunneling
+ sysARPHardwareGREIPv4 = 778 // any over GRE over IPv4 tunneling
+ sysARPHardwareGREIPv6 = 823 // any over GRE over IPv6 tunneling
+)
+
+func newLink(ifim *syscall.IfInfomsg, attrs []syscall.NetlinkRouteAttr) *Interface {
+ ifi := &Interface{Index: int(ifim.Index), Flags: linkFlags(ifim.Flags)}
+ for _, a := range attrs {
+ switch a.Attr.Type {
+ case syscall.IFLA_ADDRESS:
+ // We never return any /32 or /128 IP address
+ // prefix on any IP tunnel interface as the
+ // hardware address.
+ switch len(a.Value) {
+ case IPv4len:
+ switch ifim.Type {
+ case sysARPHardwareIPv4IPv4, sysARPHardwareGREIPv4, sysARPHardwareIPv6IPv4:
+ continue
+ }
+ case IPv6len:
+ switch ifim.Type {
+ case sysARPHardwareIPv6IPv6, sysARPHardwareGREIPv6:
+ continue
+ }
+ }
+ var nonzero bool
+ for _, b := range a.Value {
+ if b != 0 {
+ nonzero = true
+ break
+ }
+ }
+ if nonzero {
+ ifi.HardwareAddr = a.Value[:]
+ }
+ case syscall.IFLA_IFNAME:
+ ifi.Name = string(a.Value[:len(a.Value)-1])
+ case syscall.IFLA_MTU:
+ ifi.MTU = int(*(*uint32)(unsafe.Pointer(&a.Value[:4][0])))
+ }
+ }
+ return ifi
+}
+
+func linkFlags(rawFlags uint32) Flags {
+ var f Flags
+ if rawFlags&syscall.IFF_UP != 0 {
+ f |= FlagUp
+ }
+ if rawFlags&syscall.IFF_RUNNING != 0 {
+ f |= FlagRunning
+ }
+ if rawFlags&syscall.IFF_BROADCAST != 0 {
+ f |= FlagBroadcast
+ }
+ if rawFlags&syscall.IFF_LOOPBACK != 0 {
+ f |= FlagLoopback
+ }
+ if rawFlags&syscall.IFF_POINTOPOINT != 0 {
+ f |= FlagPointToPoint
+ }
+ if rawFlags&syscall.IFF_MULTICAST != 0 {
+ f |= FlagMulticast
+ }
+ return f
+}
+
+// If the ifi is nil, interfaceAddrTable returns addresses for all
+// network interfaces. Otherwise it returns addresses for a specific
+// interface.
+func interfaceAddrTable(ifi *Interface) ([]Addr, error) {
+ tab, err := syscall.NetlinkRIB(syscall.RTM_GETADDR, syscall.AF_UNSPEC)
+ if err != nil {
+ return nil, os.NewSyscallError("netlinkrib", err)
+ }
+ msgs, err := syscall.ParseNetlinkMessage(tab)
+ if err != nil {
+ return nil, os.NewSyscallError("parsenetlinkmessage", err)
+ }
+ ifat, err := addrTable(ifi, msgs)
+ if err != nil {
+ return nil, err
+ }
+ return ifat, nil
+}
+
+func addrTable(ifi *Interface, msgs []syscall.NetlinkMessage) ([]Addr, error) {
+ var ifat []Addr
+loop:
+ for _, m := range msgs {
+ switch m.Header.Type {
+ case syscall.NLMSG_DONE:
+ break loop
+ case syscall.RTM_NEWADDR:
+ ifam := (*syscall.IfAddrmsg)(unsafe.Pointer(&m.Data[0]))
+ if ifi == nil || ifi.Index == int(ifam.Index) {
+ attrs, err := syscall.ParseNetlinkRouteAttr(&m)
+ if err != nil {
+ return nil, os.NewSyscallError("parsenetlinkrouteattr", err)
+ }
+ ifa := newAddr(ifam, attrs)
+ if ifa != nil {
+ ifat = append(ifat, ifa)
+ }
+ }
+ }
+ }
+ return ifat, nil
+}
+
+func newAddr(ifam *syscall.IfAddrmsg, attrs []syscall.NetlinkRouteAttr) Addr {
+ var ipPointToPoint bool
+ // Seems like we need to make sure whether the IP interface
+ // stack consists of IP point-to-point numbered or unnumbered
+ // addressing.
+ for _, a := range attrs {
+ if a.Attr.Type == syscall.IFA_LOCAL {
+ ipPointToPoint = true
+ break
+ }
+ }
+ for _, a := range attrs {
+ if ipPointToPoint && a.Attr.Type == syscall.IFA_ADDRESS {
+ continue
+ }
+ switch ifam.Family {
+ case syscall.AF_INET:
+ return &IPNet{IP: IPv4(a.Value[0], a.Value[1], a.Value[2], a.Value[3]), Mask: CIDRMask(int(ifam.Prefixlen), 8*IPv4len)}
+ case syscall.AF_INET6:
+ ifa := &IPNet{IP: make(IP, IPv6len), Mask: CIDRMask(int(ifam.Prefixlen), 8*IPv6len)}
+ copy(ifa.IP, a.Value[:])
+ return ifa
+ }
+ }
+ return nil
+}
+
+// interfaceMulticastAddrTable returns addresses for a specific
+// interface.
+func interfaceMulticastAddrTable(ifi *Interface) ([]Addr, error) {
+ ifmat4 := parseProcNetIGMP("/proc/net/igmp", ifi)
+ ifmat6 := parseProcNetIGMP6("/proc/net/igmp6", ifi)
+ return append(ifmat4, ifmat6...), nil
+}
+
+func parseProcNetIGMP(path string, ifi *Interface) []Addr {
+ fd, err := open(path)
+ if err != nil {
+ return nil
+ }
+ defer fd.close()
+ var (
+ ifmat []Addr
+ name string
+ )
+ fd.readLine() // skip first line
+ b := make([]byte, IPv4len)
+ for l, ok := fd.readLine(); ok; l, ok = fd.readLine() {
+ f := splitAtBytes(l, " :\r\t\n")
+ if len(f) < 4 {
+ continue
+ }
+ switch {
+ case l[0] != ' ' && l[0] != '\t': // new interface line
+ name = f[1]
+ case len(f[0]) == 8:
+ if ifi == nil || name == ifi.Name {
+ // The Linux kernel puts the IP
+ // address in /proc/net/igmp in native
+ // endianness.
+ for i := 0; i+1 < len(f[0]); i += 2 {
+ b[i/2], _ = xtoi2(f[0][i:i+2], 0)
+ }
+ i := *(*uint32)(unsafe.Pointer(&b[:4][0]))
+ ifma := &IPAddr{IP: IPv4(byte(i>>24), byte(i>>16), byte(i>>8), byte(i))}
+ ifmat = append(ifmat, ifma)
+ }
+ }
+ }
+ return ifmat
+}
+
+func parseProcNetIGMP6(path string, ifi *Interface) []Addr {
+ fd, err := open(path)
+ if err != nil {
+ return nil
+ }
+ defer fd.close()
+ var ifmat []Addr
+ b := make([]byte, IPv6len)
+ for l, ok := fd.readLine(); ok; l, ok = fd.readLine() {
+ f := splitAtBytes(l, " \r\t\n")
+ if len(f) < 6 {
+ continue
+ }
+ if ifi == nil || f[1] == ifi.Name {
+ for i := 0; i+1 < len(f[2]); i += 2 {
+ b[i/2], _ = xtoi2(f[2][i:i+2], 0)
+ }
+ ifma := &IPAddr{IP: IP{b[0], b[1], b[2], b[3], b[4], b[5], b[6], b[7], b[8], b[9], b[10], b[11], b[12], b[13], b[14], b[15]}}
+ ifmat = append(ifmat, ifma)
+ }
+ }
+ return ifmat
+}
diff --git a/go/src/net/interface_linux_test.go b/go/src/net/interface_linux_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..0699fec636833f8fe36469012ebb569222e60c1b
--- /dev/null
+++ b/go/src/net/interface_linux_test.go
@@ -0,0 +1,133 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "fmt"
+ "os/exec"
+ "testing"
+)
+
+func (ti *testInterface) setBroadcast(suffix int) error {
+ ti.name = fmt.Sprintf("gotest%d", suffix)
+ xname, err := exec.LookPath("ip")
+ if err != nil {
+ return err
+ }
+ ti.setupCmds = append(ti.setupCmds, &exec.Cmd{
+ Path: xname,
+ Args: []string{"ip", "link", "add", ti.name, "type", "dummy"},
+ })
+ ti.setupCmds = append(ti.setupCmds, &exec.Cmd{
+ Path: xname,
+ Args: []string{"ip", "address", "add", ti.local, "peer", ti.remote, "dev", ti.name},
+ })
+ ti.teardownCmds = append(ti.teardownCmds, &exec.Cmd{
+ Path: xname,
+ Args: []string{"ip", "address", "del", ti.local, "peer", ti.remote, "dev", ti.name},
+ })
+ ti.teardownCmds = append(ti.teardownCmds, &exec.Cmd{
+ Path: xname,
+ Args: []string{"ip", "link", "delete", ti.name, "type", "dummy"},
+ })
+ return nil
+}
+
+func (ti *testInterface) setLinkLocal(suffix int) error {
+ ti.name = fmt.Sprintf("gotest%d", suffix)
+ xname, err := exec.LookPath("ip")
+ if err != nil {
+ return err
+ }
+ ti.setupCmds = append(ti.setupCmds, &exec.Cmd{
+ Path: xname,
+ Args: []string{"ip", "link", "add", ti.name, "type", "dummy"},
+ })
+ ti.setupCmds = append(ti.setupCmds, &exec.Cmd{
+ Path: xname,
+ Args: []string{"ip", "address", "add", ti.local, "dev", ti.name},
+ })
+ ti.teardownCmds = append(ti.teardownCmds, &exec.Cmd{
+ Path: xname,
+ Args: []string{"ip", "address", "del", ti.local, "dev", ti.name},
+ })
+ ti.teardownCmds = append(ti.teardownCmds, &exec.Cmd{
+ Path: xname,
+ Args: []string{"ip", "link", "delete", ti.name, "type", "dummy"},
+ })
+ return nil
+}
+
+func (ti *testInterface) setPointToPoint(suffix int) error {
+ ti.name = fmt.Sprintf("gotest%d", suffix)
+ xname, err := exec.LookPath("ip")
+ if err != nil {
+ return err
+ }
+ ti.setupCmds = append(ti.setupCmds, &exec.Cmd{
+ Path: xname,
+ Args: []string{"ip", "tunnel", "add", ti.name, "mode", "gre", "local", ti.local, "remote", ti.remote},
+ })
+ ti.setupCmds = append(ti.setupCmds, &exec.Cmd{
+ Path: xname,
+ Args: []string{"ip", "address", "add", ti.local, "peer", ti.remote, "dev", ti.name},
+ })
+ ti.teardownCmds = append(ti.teardownCmds, &exec.Cmd{
+ Path: xname,
+ Args: []string{"ip", "address", "del", ti.local, "peer", ti.remote, "dev", ti.name},
+ })
+ ti.teardownCmds = append(ti.teardownCmds, &exec.Cmd{
+ Path: xname,
+ Args: []string{"ip", "tunnel", "del", ti.name, "mode", "gre", "local", ti.local, "remote", ti.remote},
+ })
+ return nil
+}
+
+const (
+ numOfTestIPv4MCAddrs = 14
+ numOfTestIPv6MCAddrs = 18
+)
+
+var (
+ igmpInterfaceTable = []Interface{
+ {Name: "lo"},
+ {Name: "eth0"}, {Name: "eth1"}, {Name: "eth2"},
+ {Name: "eth0.100"}, {Name: "eth0.101"}, {Name: "eth0.102"}, {Name: "eth0.103"},
+ {Name: "device1tap2"},
+ }
+ igmp6InterfaceTable = []Interface{
+ {Name: "lo"},
+ {Name: "eth0"}, {Name: "eth1"}, {Name: "eth2"},
+ {Name: "eth0.100"}, {Name: "eth0.101"}, {Name: "eth0.102"}, {Name: "eth0.103"},
+ {Name: "device1tap2"},
+ {Name: "pan0"},
+ }
+)
+
+func TestParseProcNet(t *testing.T) {
+ defer func() {
+ if p := recover(); p != nil {
+ t.Fatalf("panicked: %v", p)
+ }
+ }()
+
+ var ifmat4 []Addr
+ for _, ifi := range igmpInterfaceTable {
+ ifmat := parseProcNetIGMP("testdata/igmp", &ifi)
+ ifmat4 = append(ifmat4, ifmat...)
+ }
+ if len(ifmat4) != numOfTestIPv4MCAddrs {
+ t.Fatalf("got %d; want %d", len(ifmat4), numOfTestIPv4MCAddrs)
+ }
+
+ var ifmat6 []Addr
+ for _, ifi := range igmp6InterfaceTable {
+ ifmat := parseProcNetIGMP6("testdata/igmp6", &ifi)
+ ifmat6 = append(ifmat6, ifmat...)
+ }
+ if len(ifmat6) != numOfTestIPv6MCAddrs {
+ t.Fatalf("got %d; want %d", len(ifmat6), numOfTestIPv6MCAddrs)
+ }
+}
diff --git a/go/src/net/interface_plan9.go b/go/src/net/interface_plan9.go
new file mode 100644
index 0000000000000000000000000000000000000000..88f1325ab22039970f9ef80666f4c327aa658eda
--- /dev/null
+++ b/go/src/net/interface_plan9.go
@@ -0,0 +1,212 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "errors"
+ "internal/strconv"
+ "internal/stringslite"
+ "os"
+)
+
+// If the ifindex is zero, interfaceTable returns mappings of all
+// network interfaces. Otherwise it returns a mapping of a specific
+// interface.
+func interfaceTable(ifindex int) ([]Interface, error) {
+ if ifindex == 0 {
+ n, err := interfaceCount()
+ if err != nil {
+ return nil, err
+ }
+ ifcs := make([]Interface, n)
+ for i := range ifcs {
+ ifc, err := readInterface(i)
+ if err != nil {
+ return nil, err
+ }
+ ifcs[i] = *ifc
+ }
+ return ifcs, nil
+ }
+
+ ifc, err := readInterface(ifindex - 1)
+ if err != nil {
+ return nil, err
+ }
+ return []Interface{*ifc}, nil
+}
+
+func readInterface(i int) (*Interface, error) {
+ ifc := &Interface{
+ Index: i + 1, // Offset the index by one to suit the contract
+ Name: netdir + "/ipifc/" + strconv.Itoa(i), // Name is the full path to the interface path in plan9
+ }
+
+ ifcstat := ifc.Name + "/status"
+ ifcstatf, err := open(ifcstat)
+ if err != nil {
+ return nil, err
+ }
+ defer ifcstatf.close()
+
+ line, ok := ifcstatf.readLine()
+ if !ok {
+ return nil, errors.New("invalid interface status file: " + ifcstat)
+ }
+
+ fields := getFields(line)
+
+ // If the interface has no device file then we see two spaces between "device" and
+ // "maxtu" and getFields treats the two spaces as one delimiter.
+ // Insert a gap for the missing device name.
+ // See https://go.dev/issue/72060.
+ if stringslite.HasPrefix(line, "device maxtu ") {
+ fields = append(fields, "")
+ copy(fields[2:], fields[1:])
+ fields[1] = ""
+ }
+
+ if len(fields) < 4 {
+ return nil, errors.New("invalid interface status file: " + ifcstat)
+ }
+
+ device := fields[1]
+ mtustr := fields[3]
+
+ mtu, _, ok := dtoi(mtustr)
+ if !ok {
+ return nil, errors.New("invalid status file of interface: " + ifcstat)
+ }
+ ifc.MTU = mtu
+
+ // Not a loopback device ("/dev/null") or packet interface (e.g. "pkt2")
+ if stringslite.HasPrefix(device, netdir+"/") {
+ deviceaddrf, err := open(device + "/addr")
+ if err != nil {
+ return nil, err
+ }
+ defer deviceaddrf.close()
+
+ line, ok = deviceaddrf.readLine()
+ if !ok {
+ return nil, errors.New("invalid address file for interface: " + device + "/addr")
+ }
+
+ if len(line) > 0 && len(line)%2 == 0 {
+ ifc.HardwareAddr = make([]byte, len(line)/2)
+ var ok bool
+ for i := range ifc.HardwareAddr {
+ j := (i + 1) * 2
+ ifc.HardwareAddr[i], ok = xtoi2(line[i*2:j], 0)
+ if !ok {
+ ifc.HardwareAddr = ifc.HardwareAddr[:i]
+ break
+ }
+ }
+ }
+
+ ifc.Flags = FlagUp | FlagRunning | FlagBroadcast | FlagMulticast
+ } else {
+ ifc.Flags = FlagUp | FlagRunning | FlagMulticast | FlagLoopback
+ }
+
+ return ifc, nil
+}
+
+func interfaceCount() (int, error) {
+ d, err := os.Open(netdir + "/ipifc")
+ if err != nil {
+ return -1, err
+ }
+ defer d.Close()
+
+ names, err := d.Readdirnames(0)
+ if err != nil {
+ return -1, err
+ }
+
+ // Assumes that numbered files in ipifc are strictly
+ // the incrementing numbered directories for the
+ // interfaces
+ c := 0
+ for _, name := range names {
+ if _, _, ok := dtoi(name); !ok {
+ continue
+ }
+ c++
+ }
+
+ return c, nil
+}
+
+// If the ifi is nil, interfaceAddrTable returns addresses for all
+// network interfaces. Otherwise it returns addresses for a specific
+// interface.
+func interfaceAddrTable(ifi *Interface) ([]Addr, error) {
+ var ifcs []Interface
+ if ifi == nil {
+ var err error
+ ifcs, err = interfaceTable(0)
+ if err != nil {
+ return nil, err
+ }
+ } else {
+ ifcs = []Interface{*ifi}
+ }
+
+ var addrs []Addr
+ for _, ifc := range ifcs {
+ status := ifc.Name + "/status"
+ statusf, err := open(status)
+ if err != nil {
+ return nil, err
+ }
+ defer statusf.close()
+
+ // Read but ignore first line as it only contains the table header.
+ // See https://9p.io/magic/man2html/3/ip
+ if _, ok := statusf.readLine(); !ok {
+ return nil, errors.New("cannot read header line for interface: " + status)
+ }
+
+ for line, ok := statusf.readLine(); ok; line, ok = statusf.readLine() {
+ fields := getFields(line)
+ if len(fields) < 1 {
+ continue
+ }
+ addr := fields[0]
+ ip := ParseIP(addr)
+ if ip == nil {
+ return nil, errors.New("cannot parse IP address for interface: " + status)
+ }
+
+ // The mask is represented as CIDR relative to the IPv6 address.
+ // Plan 9 internal representation is always IPv6.
+ maskfld := fields[1]
+ maskfld = maskfld[1:]
+ pfxlen, _, ok := dtoi(maskfld)
+ if !ok {
+ return nil, errors.New("cannot parse network mask for interface: " + status)
+ }
+ var mask IPMask
+ if ip.To4() != nil { // IPv4 or IPv6 IPv4-mapped address
+ mask = CIDRMask(pfxlen-8*len(v4InV6Prefix), 8*IPv4len)
+ }
+ if ip.To16() != nil && ip.To4() == nil { // IPv6 address
+ mask = CIDRMask(pfxlen, 8*IPv6len)
+ }
+
+ addrs = append(addrs, &IPNet{IP: ip, Mask: mask})
+ }
+ }
+
+ return addrs, nil
+}
+
+// interfaceMulticastAddrTable returns addresses for a specific
+// interface.
+func interfaceMulticastAddrTable(ifi *Interface) ([]Addr, error) {
+ return nil, nil
+}
diff --git a/go/src/net/interface_solaris.go b/go/src/net/interface_solaris.go
new file mode 100644
index 0000000000000000000000000000000000000000..32f503f45b29bac6857cd1e93f142747cc0fed4f
--- /dev/null
+++ b/go/src/net/interface_solaris.go
@@ -0,0 +1,92 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "syscall"
+
+ "golang.org/x/net/lif"
+)
+
+// If the ifindex is zero, interfaceTable returns mappings of all
+// network interfaces. Otherwise it returns a mapping of a specific
+// interface.
+func interfaceTable(ifindex int) ([]Interface, error) {
+ lls, err := lif.Links(syscall.AF_UNSPEC, "")
+ if err != nil {
+ return nil, err
+ }
+ var ift []Interface
+ for _, ll := range lls {
+ if ifindex != 0 && ifindex != ll.Index {
+ continue
+ }
+ ifi := Interface{Index: ll.Index, MTU: ll.MTU, Name: ll.Name, Flags: linkFlags(ll.Flags)}
+ if len(ll.Addr) > 0 {
+ ifi.HardwareAddr = HardwareAddr(ll.Addr)
+ }
+ ift = append(ift, ifi)
+ }
+ return ift, nil
+}
+
+func linkFlags(rawFlags int) Flags {
+ var f Flags
+ if rawFlags&syscall.IFF_UP != 0 {
+ f |= FlagUp
+ }
+ if rawFlags&syscall.IFF_RUNNING != 0 {
+ f |= FlagRunning
+ }
+ if rawFlags&syscall.IFF_BROADCAST != 0 {
+ f |= FlagBroadcast
+ }
+ if rawFlags&syscall.IFF_LOOPBACK != 0 {
+ f |= FlagLoopback
+ }
+ if rawFlags&syscall.IFF_POINTOPOINT != 0 {
+ f |= FlagPointToPoint
+ }
+ if rawFlags&syscall.IFF_MULTICAST != 0 {
+ f |= FlagMulticast
+ }
+ return f
+}
+
+// If the ifi is nil, interfaceAddrTable returns addresses for all
+// network interfaces. Otherwise it returns addresses for a specific
+// interface.
+func interfaceAddrTable(ifi *Interface) ([]Addr, error) {
+ var name string
+ if ifi != nil {
+ name = ifi.Name
+ }
+ as, err := lif.Addrs(syscall.AF_UNSPEC, name)
+ if err != nil {
+ return nil, err
+ }
+ var ifat []Addr
+ for _, a := range as {
+ var ip IP
+ var mask IPMask
+ switch a := a.(type) {
+ case *lif.Inet4Addr:
+ ip = IPv4(a.IP[0], a.IP[1], a.IP[2], a.IP[3])
+ mask = CIDRMask(a.PrefixLen, 8*IPv4len)
+ case *lif.Inet6Addr:
+ ip = make(IP, IPv6len)
+ copy(ip, a.IP[:])
+ mask = CIDRMask(a.PrefixLen, 8*IPv6len)
+ }
+ ifat = append(ifat, &IPNet{IP: ip, Mask: mask})
+ }
+ return ifat, nil
+}
+
+// interfaceMulticastAddrTable returns addresses for a specific
+// interface.
+func interfaceMulticastAddrTable(ifi *Interface) ([]Addr, error) {
+ return nil, nil
+}
diff --git a/go/src/net/interface_stub.go b/go/src/net/interface_stub.go
new file mode 100644
index 0000000000000000000000000000000000000000..4c280c6ff2efa48250d0a60359165fe32430a616
--- /dev/null
+++ b/go/src/net/interface_stub.go
@@ -0,0 +1,27 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build js || wasip1
+
+package net
+
+// If the ifindex is zero, interfaceTable returns mappings of all
+// network interfaces. Otherwise it returns a mapping of a specific
+// interface.
+func interfaceTable(ifindex int) ([]Interface, error) {
+ return nil, nil
+}
+
+// If the ifi is nil, interfaceAddrTable returns addresses for all
+// network interfaces. Otherwise it returns addresses for a specific
+// interface.
+func interfaceAddrTable(ifi *Interface) ([]Addr, error) {
+ return nil, nil
+}
+
+// interfaceMulticastAddrTable returns addresses for a specific
+// interface.
+func interfaceMulticastAddrTable(ifi *Interface) ([]Addr, error) {
+ return nil, nil
+}
diff --git a/go/src/net/interface_test.go b/go/src/net/interface_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..72befca0d89c9543c56c90d17d1cc307fcf1f243
--- /dev/null
+++ b/go/src/net/interface_test.go
@@ -0,0 +1,382 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "fmt"
+ "reflect"
+ "runtime"
+ "testing"
+)
+
+// loopbackInterface returns an available logical network interface
+// for loopback tests. It returns nil if no suitable interface is
+// found.
+func loopbackInterface() *Interface {
+ ift, err := Interfaces()
+ if err != nil {
+ return nil
+ }
+ for _, ifi := range ift {
+ if ifi.Flags&FlagLoopback != 0 && ifi.Flags&FlagUp != 0 {
+ return &ifi
+ }
+ }
+ return nil
+}
+
+// ipv6LinkLocalUnicastAddr returns an IPv6 link-local unicast address
+// on the given network interface for tests. It returns "" if no
+// suitable address is found.
+func ipv6LinkLocalUnicastAddr(ifi *Interface) string {
+ if ifi == nil {
+ return ""
+ }
+ ifat, err := ifi.Addrs()
+ if err != nil {
+ return ""
+ }
+ for _, ifa := range ifat {
+ if ifa, ok := ifa.(*IPNet); ok {
+ if ifa.IP.To4() == nil && ifa.IP.IsLinkLocalUnicast() {
+ return ifa.IP.String()
+ }
+ }
+ }
+ return ""
+}
+
+func TestInterfaces(t *testing.T) {
+ ift, err := Interfaces()
+ if err != nil {
+ t.Fatal(err)
+ }
+ for _, ifi := range ift {
+ ifxi, err := InterfaceByIndex(ifi.Index)
+ if err != nil {
+ t.Fatal(err)
+ }
+ switch runtime.GOOS {
+ case "solaris", "illumos":
+ if ifxi.Index != ifi.Index {
+ t.Errorf("got %v; want %v", ifxi, ifi)
+ }
+ default:
+ if !reflect.DeepEqual(ifxi, &ifi) {
+ t.Errorf("got %v; want %v", ifxi, ifi)
+ }
+ }
+ if ifi.Name != "" {
+ ifxn, err := InterfaceByName(ifi.Name)
+ if err != nil {
+ t.Fatal(err)
+ }
+ if !reflect.DeepEqual(ifxn, &ifi) {
+ t.Errorf("got %v; want %v", ifxn, ifi)
+ }
+ }
+ t.Logf("%s: flags=%v index=%d mtu=%d hwaddr=%v", ifi.Name, ifi.Flags, ifi.Index, ifi.MTU, ifi.HardwareAddr)
+ }
+}
+
+func TestInterfaceAddrs(t *testing.T) {
+ ift, err := Interfaces()
+ if err != nil {
+ t.Fatal(err)
+ }
+ ifStats := interfaceStats(ift)
+ ifat, err := InterfaceAddrs()
+ if err != nil {
+ t.Fatal(err)
+ }
+ uniStats, err := validateInterfaceUnicastAddrs(ifat)
+ if err != nil {
+ t.Fatal(err)
+ }
+ if err := checkUnicastStats(ifStats, uniStats); err != nil {
+ t.Fatal(err)
+ }
+}
+
+func TestInterfaceUnicastAddrs(t *testing.T) {
+ ift, err := Interfaces()
+ if err != nil {
+ t.Fatal(err)
+ }
+ ifStats := interfaceStats(ift)
+ if err != nil {
+ t.Fatal(err)
+ }
+ var uniStats routeStats
+ for _, ifi := range ift {
+ ifat, err := ifi.Addrs()
+ if err != nil {
+ t.Fatal(ifi, err)
+ }
+ stats, err := validateInterfaceUnicastAddrs(ifat)
+ if err != nil {
+ t.Fatal(ifi, err)
+ }
+ uniStats.ipv4 += stats.ipv4
+ uniStats.ipv6 += stats.ipv6
+ }
+ if err := checkUnicastStats(ifStats, &uniStats); err != nil {
+ t.Fatal(err)
+ }
+}
+
+func TestInterfaceMulticastAddrs(t *testing.T) {
+ ift, err := Interfaces()
+ if err != nil {
+ t.Fatal(err)
+ }
+ ifStats := interfaceStats(ift)
+ ifat, err := InterfaceAddrs()
+ if err != nil {
+ t.Fatal(err)
+ }
+ uniStats, err := validateInterfaceUnicastAddrs(ifat)
+ if err != nil {
+ t.Fatal(err)
+ }
+ var multiStats routeStats
+ for _, ifi := range ift {
+ ifmat, err := ifi.MulticastAddrs()
+ if err != nil {
+ t.Fatal(ifi, err)
+ }
+ stats, err := validateInterfaceMulticastAddrs(ifmat)
+ if err != nil {
+ t.Fatal(ifi, err)
+ }
+ multiStats.ipv4 += stats.ipv4
+ multiStats.ipv6 += stats.ipv6
+ }
+ if err := checkMulticastStats(ifStats, uniStats, &multiStats); err != nil {
+ t.Fatal(err)
+ }
+}
+
+type ifStats struct {
+ loop int // # of active loopback interfaces
+ other int // # of active other interfaces
+}
+
+func interfaceStats(ift []Interface) *ifStats {
+ var stats ifStats
+ for _, ifi := range ift {
+ if ifi.Flags&FlagUp != 0 {
+ if ifi.Flags&FlagLoopback != 0 {
+ stats.loop++
+ } else {
+ stats.other++
+ }
+ }
+ }
+ return &stats
+}
+
+type routeStats struct {
+ ipv4, ipv6 int // # of active connected unicast, anycast or multicast routes
+}
+
+func validateInterfaceUnicastAddrs(ifat []Addr) (*routeStats, error) {
+ // Note: BSD variants allow assigning any IPv4/IPv6 address
+ // prefix to IP interface. For example,
+ // - 0.0.0.0/0 through 255.255.255.255/32
+ // - ::/0 through ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff/128
+ // In other words, there is no tightly-coupled combination of
+ // interface address prefixes and connected routes.
+ stats := new(routeStats)
+ for _, ifa := range ifat {
+ switch ifa := ifa.(type) {
+ case *IPNet:
+ if ifa == nil || ifa.IP == nil || ifa.IP.IsMulticast() || ifa.Mask == nil {
+ return nil, fmt.Errorf("unexpected value: %#v", ifa)
+ }
+ if len(ifa.IP) != IPv6len {
+ return nil, fmt.Errorf("should be internal representation either IPv6 or IPv4-mapped IPv6 address: %#v", ifa)
+ }
+ prefixLen, maxPrefixLen := ifa.Mask.Size()
+ if ifa.IP.To4() != nil {
+ if 0 >= prefixLen || prefixLen > 8*IPv4len || maxPrefixLen != 8*IPv4len {
+ return nil, fmt.Errorf("unexpected prefix length: %d/%d for %#v", prefixLen, maxPrefixLen, ifa)
+ }
+ if ifa.IP.IsLoopback() && prefixLen < 8 { // see RFC 1122
+ return nil, fmt.Errorf("unexpected prefix length: %d/%d for %#v", prefixLen, maxPrefixLen, ifa)
+ }
+ stats.ipv4++
+ }
+ if ifa.IP.To16() != nil && ifa.IP.To4() == nil {
+ if 0 >= prefixLen || prefixLen > 8*IPv6len || maxPrefixLen != 8*IPv6len {
+ return nil, fmt.Errorf("unexpected prefix length: %d/%d for %#v", prefixLen, maxPrefixLen, ifa)
+ }
+ if ifa.IP.IsLoopback() && prefixLen != 8*IPv6len { // see RFC 4291
+ return nil, fmt.Errorf("unexpected prefix length: %d/%d for %#v", prefixLen, maxPrefixLen, ifa)
+ }
+ stats.ipv6++
+ }
+ case *IPAddr:
+ if ifa == nil || ifa.IP == nil || ifa.IP.IsMulticast() {
+ return nil, fmt.Errorf("unexpected value: %#v", ifa)
+ }
+ if len(ifa.IP) != IPv6len {
+ return nil, fmt.Errorf("should be internal representation either IPv6 or IPv4-mapped IPv6 address: %#v", ifa)
+ }
+ if ifa.IP.To4() != nil {
+ stats.ipv4++
+ }
+ if ifa.IP.To16() != nil && ifa.IP.To4() == nil {
+ stats.ipv6++
+ }
+ default:
+ return nil, fmt.Errorf("unexpected type: %T", ifa)
+ }
+ }
+ return stats, nil
+}
+
+func validateInterfaceMulticastAddrs(ifat []Addr) (*routeStats, error) {
+ stats := new(routeStats)
+ for _, ifa := range ifat {
+ switch ifa := ifa.(type) {
+ case *IPAddr:
+ if ifa == nil || ifa.IP == nil || ifa.IP.IsUnspecified() || !ifa.IP.IsMulticast() {
+ return nil, fmt.Errorf("unexpected value: %#v", ifa)
+ }
+ if len(ifa.IP) != IPv6len {
+ return nil, fmt.Errorf("should be internal representation either IPv6 or IPv4-mapped IPv6 address: %#v", ifa)
+ }
+ if ifa.IP.To4() != nil {
+ stats.ipv4++
+ }
+ if ifa.IP.To16() != nil && ifa.IP.To4() == nil {
+ stats.ipv6++
+ }
+ default:
+ return nil, fmt.Errorf("unexpected type: %T", ifa)
+ }
+ }
+ return stats, nil
+}
+
+func checkUnicastStats(ifStats *ifStats, uniStats *routeStats) error {
+ // Test the existence of connected unicast routes for IPv4.
+ if supportsIPv4() && ifStats.loop+ifStats.other > 0 && uniStats.ipv4 == 0 {
+ return fmt.Errorf("num IPv4 unicast routes = 0; want >0; summary: %+v, %+v", ifStats, uniStats)
+ }
+ // Test the existence of connected unicast routes for IPv6.
+ // We can assume the existence of ::1/128 when at least one
+ // loopback interface is installed.
+ if supportsIPv6() && ifStats.loop > 0 && uniStats.ipv6 == 0 {
+ return fmt.Errorf("num IPv6 unicast routes = 0; want >0; summary: %+v, %+v", ifStats, uniStats)
+ }
+ return nil
+}
+
+func checkMulticastStats(ifStats *ifStats, uniStats, multiStats *routeStats) error {
+ switch runtime.GOOS {
+ case "aix", "dragonfly", "netbsd", "openbsd", "plan9", "solaris", "illumos":
+ default:
+ // Test the existence of connected multicast route
+ // clones for IPv4. Unlike IPv6, IPv4 multicast
+ // capability is not a mandatory feature, and so IPv4
+ // multicast validation is ignored and we only check
+ // IPv6 below.
+ //
+ // Test the existence of connected multicast route
+ // clones for IPv6. Some platform never uses loopback
+ // interface as the nexthop for multicast routing.
+ // We can assume the existence of connected multicast
+ // route clones when at least two connected unicast
+ // routes, ::1/128 and other, are installed.
+ if supportsIPv6() && ifStats.loop > 0 && uniStats.ipv6 > 1 && multiStats.ipv6 == 0 {
+ return fmt.Errorf("num IPv6 multicast route clones = 0; want >0; summary: %+v, %+v, %+v", ifStats, uniStats, multiStats)
+ }
+ }
+ return nil
+}
+
+func BenchmarkInterfaces(b *testing.B) {
+ b.ReportAllocs()
+ testHookUninstaller.Do(uninstallTestHooks)
+
+ for i := 0; i < b.N; i++ {
+ if _, err := Interfaces(); err != nil {
+ b.Fatal(err)
+ }
+ }
+}
+
+func BenchmarkInterfaceByIndex(b *testing.B) {
+ b.ReportAllocs()
+ testHookUninstaller.Do(uninstallTestHooks)
+
+ ifi := loopbackInterface()
+ if ifi == nil {
+ b.Skip("loopback interface not found")
+ }
+ for i := 0; i < b.N; i++ {
+ if _, err := InterfaceByIndex(ifi.Index); err != nil {
+ b.Fatal(err)
+ }
+ }
+}
+
+func BenchmarkInterfaceByName(b *testing.B) {
+ b.ReportAllocs()
+ testHookUninstaller.Do(uninstallTestHooks)
+
+ ifi := loopbackInterface()
+ if ifi == nil {
+ b.Skip("loopback interface not found")
+ }
+ for i := 0; i < b.N; i++ {
+ if _, err := InterfaceByName(ifi.Name); err != nil {
+ b.Fatal(err)
+ }
+ }
+}
+
+func BenchmarkInterfaceAddrs(b *testing.B) {
+ b.ReportAllocs()
+ testHookUninstaller.Do(uninstallTestHooks)
+
+ for i := 0; i < b.N; i++ {
+ if _, err := InterfaceAddrs(); err != nil {
+ b.Fatal(err)
+ }
+ }
+}
+
+func BenchmarkInterfacesAndAddrs(b *testing.B) {
+ b.ReportAllocs()
+ testHookUninstaller.Do(uninstallTestHooks)
+
+ ifi := loopbackInterface()
+ if ifi == nil {
+ b.Skip("loopback interface not found")
+ }
+ for i := 0; i < b.N; i++ {
+ if _, err := ifi.Addrs(); err != nil {
+ b.Fatal(err)
+ }
+ }
+}
+
+func BenchmarkInterfacesAndMulticastAddrs(b *testing.B) {
+ b.ReportAllocs()
+ testHookUninstaller.Do(uninstallTestHooks)
+
+ ifi := loopbackInterface()
+ if ifi == nil {
+ b.Skip("loopback interface not found")
+ }
+ for i := 0; i < b.N; i++ {
+ if _, err := ifi.MulticastAddrs(); err != nil {
+ b.Fatal(err)
+ }
+ }
+}
diff --git a/go/src/net/interface_unix_test.go b/go/src/net/interface_unix_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..b0a9bcf253d1ce20f7c08c3e976d7f28abf5de62
--- /dev/null
+++ b/go/src/net/interface_unix_test.go
@@ -0,0 +1,215 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build darwin || dragonfly || freebsd || linux || netbsd || openbsd
+
+package net
+
+import (
+ "fmt"
+ "os"
+ "os/exec"
+ "runtime"
+ "strings"
+ "testing"
+ "time"
+)
+
+type testInterface struct {
+ name string
+ local string
+ remote string
+ setupCmds []*exec.Cmd
+ teardownCmds []*exec.Cmd
+}
+
+func (ti *testInterface) setup() error {
+ for _, cmd := range ti.setupCmds {
+ if out, err := cmd.CombinedOutput(); err != nil {
+ return fmt.Errorf("args=%v out=%q err=%v", cmd.Args, string(out), err)
+ }
+ }
+ return nil
+}
+
+func (ti *testInterface) teardown() error {
+ for _, cmd := range ti.teardownCmds {
+ if out, err := cmd.CombinedOutput(); err != nil {
+ return fmt.Errorf("args=%v out=%q err=%v ", cmd.Args, string(out), err)
+ }
+ }
+ return nil
+}
+
+func TestPointToPointInterface(t *testing.T) {
+ if testing.Short() {
+ t.Skip("avoid external network")
+ }
+ if runtime.GOOS == "darwin" || runtime.GOOS == "ios" {
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+ if os.Getuid() != 0 {
+ t.Skip("must be root")
+ }
+
+ // We suppose that using IPv4 link-local addresses doesn't
+ // harm anyone.
+ local, remote := "169.254.0.1", "169.254.0.254"
+ ip := ParseIP(remote)
+ for i := 0; i < 3; i++ {
+ ti := &testInterface{local: local, remote: remote}
+ if err := ti.setPointToPoint(5963 + i); err != nil {
+ t.Skipf("test requires external command: %v", err)
+ }
+ if err := ti.setup(); err != nil {
+ if e := err.Error(); strings.Contains(e, "No such device") && strings.Contains(e, "gre0") {
+ t.Skip("skipping test; no gre0 device. likely running in container?")
+ }
+ t.Fatal(err)
+ } else {
+ time.Sleep(3 * time.Millisecond)
+ }
+ ift, err := Interfaces()
+ if err != nil {
+ ti.teardown()
+ t.Fatal(err)
+ }
+ for _, ifi := range ift {
+ if ti.name != ifi.Name {
+ continue
+ }
+ ifat, err := ifi.Addrs()
+ if err != nil {
+ ti.teardown()
+ t.Fatal(err)
+ }
+ for _, ifa := range ifat {
+ if ip.Equal(ifa.(*IPNet).IP) {
+ ti.teardown()
+ t.Fatalf("got %v", ifa)
+ }
+ }
+ }
+ if err := ti.teardown(); err != nil {
+ t.Fatal(err)
+ } else {
+ time.Sleep(3 * time.Millisecond)
+ }
+ }
+}
+
+func TestInterfaceArrivalAndDeparture(t *testing.T) {
+ if testing.Short() {
+ t.Skip("avoid external network")
+ }
+ if os.Getuid() != 0 {
+ t.Skip("must be root")
+ }
+
+ // We suppose that using IPv4 link-local addresses and the
+ // dot1Q ID for Token Ring and FDDI doesn't harm anyone.
+ local, remote := "169.254.0.1", "169.254.0.254"
+ ip := ParseIP(remote)
+ for _, vid := range []int{1002, 1003, 1004, 1005} {
+ ift1, err := Interfaces()
+ if err != nil {
+ t.Fatal(err)
+ }
+ ti := &testInterface{local: local, remote: remote}
+ if err := ti.setBroadcast(vid); err != nil {
+ t.Skipf("test requires external command: %v", err)
+ }
+ if err := ti.setup(); err != nil {
+ t.Fatal(err)
+ } else {
+ time.Sleep(3 * time.Millisecond)
+ }
+ ift2, err := Interfaces()
+ if err != nil {
+ ti.teardown()
+ t.Fatal(err)
+ }
+ if len(ift2) <= len(ift1) {
+ for _, ifi := range ift1 {
+ t.Logf("before: %v", ifi)
+ }
+ for _, ifi := range ift2 {
+ t.Logf("after: %v", ifi)
+ }
+ ti.teardown()
+ t.Fatalf("got %v; want gt %v", len(ift2), len(ift1))
+ }
+ for _, ifi := range ift2 {
+ if ti.name != ifi.Name {
+ continue
+ }
+ ifat, err := ifi.Addrs()
+ if err != nil {
+ ti.teardown()
+ t.Fatal(err)
+ }
+ for _, ifa := range ifat {
+ if ip.Equal(ifa.(*IPNet).IP) {
+ ti.teardown()
+ t.Fatalf("got %v", ifa)
+ }
+ }
+ }
+ if err := ti.teardown(); err != nil {
+ t.Fatal(err)
+ } else {
+ time.Sleep(3 * time.Millisecond)
+ }
+ ift3, err := Interfaces()
+ if err != nil {
+ t.Fatal(err)
+ }
+ if len(ift3) >= len(ift2) {
+ for _, ifi := range ift2 {
+ t.Logf("before: %v", ifi)
+ }
+ for _, ifi := range ift3 {
+ t.Logf("after: %v", ifi)
+ }
+ t.Fatalf("got %v; want lt %v", len(ift3), len(ift2))
+ }
+ }
+}
+
+func TestInterfaceArrivalAndDepartureZoneCache(t *testing.T) {
+ if testing.Short() {
+ t.Skip("avoid external network")
+ }
+ if os.Getuid() != 0 {
+ t.Skip("must be root")
+ }
+
+ // Ensure zoneCache is filled:
+ _, _ = Listen("tcp", "[fe80::1%nonexistent]:0")
+
+ ti := &testInterface{local: "fe80::1"}
+ if err := ti.setLinkLocal(0); err != nil {
+ t.Skipf("test requires external command: %v", err)
+ }
+ if err := ti.setup(); err != nil {
+ if e := err.Error(); strings.Contains(e, "Permission denied") {
+ t.Skipf("permission denied, skipping test: %v", e)
+ }
+ t.Fatal(err)
+ }
+ defer ti.teardown()
+
+ time.Sleep(3 * time.Millisecond)
+
+ // If Listen fails (on Linux with “bind: invalid argument”), zoneCache was
+ // not updated when encountering a nonexistent interface:
+ ln, err := Listen("tcp", "[fe80::1%"+ti.name+"]:0")
+ if err != nil {
+ t.Fatal(err)
+ }
+ ln.Close()
+ if err := ti.teardown(); err != nil {
+ t.Fatal(err)
+ }
+}
diff --git a/go/src/net/interface_windows.go b/go/src/net/interface_windows.go
new file mode 100644
index 0000000000000000000000000000000000000000..7a5cb5723f1b6bce3239a7ed30fe0d7b5074f25d
--- /dev/null
+++ b/go/src/net/interface_windows.go
@@ -0,0 +1,179 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "internal/syscall/windows"
+ "os"
+ "syscall"
+ "unsafe"
+)
+
+// adapterAddresses returns a list of IP adapter and address
+// structures. The structure contains an IP adapter and flattened
+// multiple IP addresses including unicast, anycast and multicast
+// addresses.
+func adapterAddresses() ([]*windows.IpAdapterAddresses, error) {
+ var b []byte
+ l := uint32(15000) // recommended initial size
+ for {
+ b = make([]byte, l)
+ const flags = windows.GAA_FLAG_INCLUDE_PREFIX | windows.GAA_FLAG_INCLUDE_GATEWAYS
+ err := windows.GetAdaptersAddresses(syscall.AF_UNSPEC, flags, nil, (*windows.IpAdapterAddresses)(unsafe.Pointer(&b[0])), &l)
+ if err == nil {
+ if l == 0 {
+ return nil, nil
+ }
+ break
+ }
+ if err.(syscall.Errno) != syscall.ERROR_BUFFER_OVERFLOW {
+ return nil, os.NewSyscallError("getadaptersaddresses", err)
+ }
+ if l <= uint32(len(b)) {
+ return nil, os.NewSyscallError("getadaptersaddresses", err)
+ }
+ }
+ var aas []*windows.IpAdapterAddresses
+ for aa := (*windows.IpAdapterAddresses)(unsafe.Pointer(&b[0])); aa != nil; aa = aa.Next {
+ aas = append(aas, aa)
+ }
+ return aas, nil
+}
+
+// If the ifindex is zero, interfaceTable returns mappings of all
+// network interfaces. Otherwise it returns a mapping of a specific
+// interface.
+func interfaceTable(ifindex int) ([]Interface, error) {
+ aas, err := adapterAddresses()
+ if err != nil {
+ return nil, err
+ }
+ var ift []Interface
+ for _, aa := range aas {
+ index := aa.IfIndex
+ if index == 0 { // ipv6IfIndex is a substitute for ifIndex
+ index = aa.Ipv6IfIndex
+ }
+ if ifindex == 0 || ifindex == int(index) {
+ ifi := Interface{
+ Index: int(index),
+ Name: windows.UTF16PtrToString(aa.FriendlyName),
+ }
+ if aa.OperStatus == windows.IfOperStatusUp {
+ ifi.Flags |= FlagUp
+ ifi.Flags |= FlagRunning
+ }
+ // For now we need to infer link-layer service
+ // capabilities from media types.
+ // TODO: use MIB_IF_ROW2.AccessType now that we no longer support
+ // Windows XP.
+ switch aa.IfType {
+ case windows.IF_TYPE_ETHERNET_CSMACD, windows.IF_TYPE_ISO88025_TOKENRING, windows.IF_TYPE_IEEE80211, windows.IF_TYPE_IEEE1394:
+ ifi.Flags |= FlagBroadcast | FlagMulticast
+ case windows.IF_TYPE_PPP, windows.IF_TYPE_TUNNEL:
+ ifi.Flags |= FlagPointToPoint | FlagMulticast
+ case windows.IF_TYPE_SOFTWARE_LOOPBACK:
+ ifi.Flags |= FlagLoopback | FlagMulticast
+ case windows.IF_TYPE_ATM:
+ ifi.Flags |= FlagBroadcast | FlagPointToPoint | FlagMulticast // assume all services available; LANE, point-to-point and point-to-multipoint
+ }
+ if aa.Mtu == 0xffffffff {
+ ifi.MTU = -1
+ } else {
+ ifi.MTU = int(aa.Mtu)
+ }
+ if aa.PhysicalAddressLength > 0 {
+ ifi.HardwareAddr = make(HardwareAddr, aa.PhysicalAddressLength)
+ copy(ifi.HardwareAddr, aa.PhysicalAddress[:])
+ }
+ ift = append(ift, ifi)
+ if ifindex == ifi.Index {
+ break
+ }
+ }
+ }
+ return ift, nil
+}
+
+// If the ifi is nil, interfaceAddrTable returns addresses for all
+// network interfaces. Otherwise it returns addresses for a specific
+// interface.
+func interfaceAddrTable(ifi *Interface) ([]Addr, error) {
+ aas, err := adapterAddresses()
+ if err != nil {
+ return nil, err
+ }
+ var ifat []Addr
+ for _, aa := range aas {
+ index := aa.IfIndex
+ if index == 0 { // ipv6IfIndex is a substitute for ifIndex
+ index = aa.Ipv6IfIndex
+ }
+ if ifi == nil || ifi.Index == int(index) {
+ for puni := aa.FirstUnicastAddress; puni != nil; puni = puni.Next {
+ sa, err := puni.Address.Sockaddr.Sockaddr()
+ if err != nil {
+ return nil, os.NewSyscallError("sockaddr", err)
+ }
+ switch sa := sa.(type) {
+ case *syscall.SockaddrInet4:
+ ifat = append(ifat, &IPNet{IP: IPv4(sa.Addr[0], sa.Addr[1], sa.Addr[2], sa.Addr[3]), Mask: CIDRMask(int(puni.OnLinkPrefixLength), 8*IPv4len)})
+ case *syscall.SockaddrInet6:
+ ifa := &IPNet{IP: make(IP, IPv6len), Mask: CIDRMask(int(puni.OnLinkPrefixLength), 8*IPv6len)}
+ copy(ifa.IP, sa.Addr[:])
+ ifat = append(ifat, ifa)
+ }
+ }
+ for pany := aa.FirstAnycastAddress; pany != nil; pany = pany.Next {
+ sa, err := pany.Address.Sockaddr.Sockaddr()
+ if err != nil {
+ return nil, os.NewSyscallError("sockaddr", err)
+ }
+ switch sa := sa.(type) {
+ case *syscall.SockaddrInet4:
+ ifat = append(ifat, &IPAddr{IP: IPv4(sa.Addr[0], sa.Addr[1], sa.Addr[2], sa.Addr[3])})
+ case *syscall.SockaddrInet6:
+ ifa := &IPAddr{IP: make(IP, IPv6len)}
+ copy(ifa.IP, sa.Addr[:])
+ ifat = append(ifat, ifa)
+ }
+ }
+ }
+ }
+ return ifat, nil
+}
+
+// interfaceMulticastAddrTable returns addresses for a specific
+// interface.
+func interfaceMulticastAddrTable(ifi *Interface) ([]Addr, error) {
+ aas, err := adapterAddresses()
+ if err != nil {
+ return nil, err
+ }
+ var ifat []Addr
+ for _, aa := range aas {
+ index := aa.IfIndex
+ if index == 0 { // ipv6IfIndex is a substitute for ifIndex
+ index = aa.Ipv6IfIndex
+ }
+ if ifi == nil || ifi.Index == int(index) {
+ for pmul := aa.FirstMulticastAddress; pmul != nil; pmul = pmul.Next {
+ sa, err := pmul.Address.Sockaddr.Sockaddr()
+ if err != nil {
+ return nil, os.NewSyscallError("sockaddr", err)
+ }
+ switch sa := sa.(type) {
+ case *syscall.SockaddrInet4:
+ ifat = append(ifat, &IPAddr{IP: IPv4(sa.Addr[0], sa.Addr[1], sa.Addr[2], sa.Addr[3])})
+ case *syscall.SockaddrInet6:
+ ifa := &IPAddr{IP: make(IP, IPv6len)}
+ copy(ifa.IP, sa.Addr[:])
+ ifat = append(ifat, ifa)
+ }
+ }
+ }
+ }
+ return ifat, nil
+}
diff --git a/go/src/net/ip.go b/go/src/net/ip.go
new file mode 100644
index 0000000000000000000000000000000000000000..7d58e89e112786d8b38cdb1db85d6ed73afc6601
--- /dev/null
+++ b/go/src/net/ip.go
@@ -0,0 +1,574 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// IP address manipulations
+//
+// IPv4 addresses are 4 bytes; IPv6 addresses are 16 bytes.
+// An IPv4 address can be converted to an IPv6 address by
+// adding a canonical prefix (10 zeros, 2 0xFFs).
+// This library accepts either size of byte slice but always
+// returns 16-byte addresses.
+
+package net
+
+import (
+ "internal/bytealg"
+ "internal/strconv"
+ "internal/stringslite"
+ "net/netip"
+)
+
+// IP address lengths (bytes).
+const (
+ IPv4len = 4
+ IPv6len = 16
+)
+
+// An IP is a single IP address, a slice of bytes.
+// Functions in this package accept either 4-byte (IPv4)
+// or 16-byte (IPv6) slices as input.
+//
+// Note that in this documentation, referring to an
+// IP address as an IPv4 address or an IPv6 address
+// is a semantic property of the address, not just the
+// length of the byte slice: a 16-byte slice can still
+// be an IPv4 address.
+type IP []byte
+
+// An IPMask is a bitmask that can be used to manipulate
+// IP addresses for IP addressing and routing.
+//
+// See type [IPNet] and func [ParseCIDR] for details.
+type IPMask []byte
+
+// An IPNet represents an IP network.
+type IPNet struct {
+ IP IP // network number
+ Mask IPMask // network mask
+}
+
+// IPv4 returns the IP address (in 16-byte form) of the
+// IPv4 address a.b.c.d.
+func IPv4(a, b, c, d byte) IP {
+ p := make(IP, IPv6len)
+ copy(p, v4InV6Prefix)
+ p[12] = a
+ p[13] = b
+ p[14] = c
+ p[15] = d
+ return p
+}
+
+var v4InV6Prefix = []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xff, 0xff}
+
+// IPv4Mask returns the IP mask (in 4-byte form) of the
+// IPv4 mask a.b.c.d.
+func IPv4Mask(a, b, c, d byte) IPMask {
+ p := make(IPMask, IPv4len)
+ p[0] = a
+ p[1] = b
+ p[2] = c
+ p[3] = d
+ return p
+}
+
+// CIDRMask returns an [IPMask] consisting of 'ones' 1 bits
+// followed by 0s up to a total length of 'bits' bits.
+// For a mask of this form, CIDRMask is the inverse of [IPMask.Size].
+func CIDRMask(ones, bits int) IPMask {
+ if bits != 8*IPv4len && bits != 8*IPv6len {
+ return nil
+ }
+ if ones < 0 || ones > bits {
+ return nil
+ }
+ l := bits / 8
+ m := make(IPMask, l)
+ n := uint(ones)
+ for i := 0; i < l; i++ {
+ if n >= 8 {
+ m[i] = 0xff
+ n -= 8
+ continue
+ }
+ m[i] = ^byte(0xff >> n)
+ n = 0
+ }
+ return m
+}
+
+// Well-known IPv4 addresses
+var (
+ IPv4bcast = IPv4(255, 255, 255, 255) // limited broadcast
+ IPv4allsys = IPv4(224, 0, 0, 1) // all systems
+ IPv4allrouter = IPv4(224, 0, 0, 2) // all routers
+ IPv4zero = IPv4(0, 0, 0, 0) // all zeros
+)
+
+// Well-known IPv6 addresses
+var (
+ IPv6zero = IP{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
+ IPv6unspecified = IP{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
+ IPv6loopback = IP{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}
+ IPv6interfacelocalallnodes = IP{0xff, 0x01, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x01}
+ IPv6linklocalallnodes = IP{0xff, 0x02, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x01}
+ IPv6linklocalallrouters = IP{0xff, 0x02, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x02}
+)
+
+// IsUnspecified reports whether ip is an unspecified address, either
+// the IPv4 address "0.0.0.0" or the IPv6 address "::".
+func (ip IP) IsUnspecified() bool {
+ return ip.Equal(IPv4zero) || ip.Equal(IPv6unspecified)
+}
+
+// IsLoopback reports whether ip is a loopback address.
+func (ip IP) IsLoopback() bool {
+ if ip4 := ip.To4(); ip4 != nil {
+ return ip4[0] == 127
+ }
+ return ip.Equal(IPv6loopback)
+}
+
+// IsPrivate reports whether ip is a private address, according to
+// RFC 1918 (IPv4 addresses) and RFC 4193 (IPv6 addresses).
+func (ip IP) IsPrivate() bool {
+ if ip4 := ip.To4(); ip4 != nil {
+ // Following RFC 1918, Section 3. Private Address Space which says:
+ // The Internet Assigned Numbers Authority (IANA) has reserved the
+ // following three blocks of the IP address space for private internets:
+ // 10.0.0.0 - 10.255.255.255 (10/8 prefix)
+ // 172.16.0.0 - 172.31.255.255 (172.16/12 prefix)
+ // 192.168.0.0 - 192.168.255.255 (192.168/16 prefix)
+ return ip4[0] == 10 ||
+ (ip4[0] == 172 && ip4[1]&0xf0 == 16) ||
+ (ip4[0] == 192 && ip4[1] == 168)
+ }
+ // Following RFC 4193, Section 8. IANA Considerations which says:
+ // The IANA has assigned the FC00::/7 prefix to "Unique Local Unicast".
+ return len(ip) == IPv6len && ip[0]&0xfe == 0xfc
+}
+
+// IsMulticast reports whether ip is a multicast address.
+func (ip IP) IsMulticast() bool {
+ if ip4 := ip.To4(); ip4 != nil {
+ return ip4[0]&0xf0 == 0xe0
+ }
+ return len(ip) == IPv6len && ip[0] == 0xff
+}
+
+// IsInterfaceLocalMulticast reports whether ip is
+// an interface-local multicast address.
+func (ip IP) IsInterfaceLocalMulticast() bool {
+ return len(ip) == IPv6len && ip[0] == 0xff && ip[1]&0x0f == 0x01
+}
+
+// IsLinkLocalMulticast reports whether ip is a link-local
+// multicast address.
+func (ip IP) IsLinkLocalMulticast() bool {
+ if ip4 := ip.To4(); ip4 != nil {
+ return ip4[0] == 224 && ip4[1] == 0 && ip4[2] == 0
+ }
+ return len(ip) == IPv6len && ip[0] == 0xff && ip[1]&0x0f == 0x02
+}
+
+// IsLinkLocalUnicast reports whether ip is a link-local
+// unicast address.
+func (ip IP) IsLinkLocalUnicast() bool {
+ if ip4 := ip.To4(); ip4 != nil {
+ return ip4[0] == 169 && ip4[1] == 254
+ }
+ return len(ip) == IPv6len && ip[0] == 0xfe && ip[1]&0xc0 == 0x80
+}
+
+// IsGlobalUnicast reports whether ip is a global unicast
+// address.
+//
+// The identification of global unicast addresses uses address type
+// identification as defined in RFC 1122, RFC 4632 and RFC 4291 with
+// the exception of IPv4 directed broadcast addresses.
+// It returns true even if ip is in IPv4 private address space or
+// local IPv6 unicast address space.
+func (ip IP) IsGlobalUnicast() bool {
+ return (len(ip) == IPv4len || len(ip) == IPv6len) &&
+ !ip.Equal(IPv4bcast) &&
+ !ip.IsUnspecified() &&
+ !ip.IsLoopback() &&
+ !ip.IsMulticast() &&
+ !ip.IsLinkLocalUnicast()
+}
+
+// Is p all zeros?
+func isZeros(p IP) bool {
+ for i := 0; i < len(p); i++ {
+ if p[i] != 0 {
+ return false
+ }
+ }
+ return true
+}
+
+// To4 converts the IPv4 address ip to a 4-byte representation.
+// If ip is not an IPv4 address, To4 returns nil.
+func (ip IP) To4() IP {
+ if len(ip) == IPv4len {
+ return ip
+ }
+ if len(ip) == IPv6len &&
+ isZeros(ip[0:10]) &&
+ ip[10] == 0xff &&
+ ip[11] == 0xff {
+ return ip[12:16]
+ }
+ return nil
+}
+
+// To16 converts the IP address ip to a 16-byte representation.
+// If ip is not an IP address (it is the wrong length), To16 returns nil.
+func (ip IP) To16() IP {
+ if len(ip) == IPv4len {
+ return IPv4(ip[0], ip[1], ip[2], ip[3])
+ }
+ if len(ip) == IPv6len {
+ return ip
+ }
+ return nil
+}
+
+// Default route masks for IPv4.
+var (
+ classAMask = IPv4Mask(0xff, 0, 0, 0)
+ classBMask = IPv4Mask(0xff, 0xff, 0, 0)
+ classCMask = IPv4Mask(0xff, 0xff, 0xff, 0)
+)
+
+// DefaultMask returns the default IP mask for the IP address ip.
+// Only IPv4 addresses have default masks; DefaultMask returns
+// nil if ip is not a valid IPv4 address.
+func (ip IP) DefaultMask() IPMask {
+ if ip = ip.To4(); ip == nil {
+ return nil
+ }
+ switch {
+ case ip[0] < 0x80:
+ return classAMask
+ case ip[0] < 0xC0:
+ return classBMask
+ default:
+ return classCMask
+ }
+}
+
+func allFF(b []byte) bool {
+ for _, c := range b {
+ if c != 0xff {
+ return false
+ }
+ }
+ return true
+}
+
+// Mask returns the result of masking the IP address ip with mask.
+func (ip IP) Mask(mask IPMask) IP {
+ if len(mask) == IPv6len && len(ip) == IPv4len && allFF(mask[:12]) {
+ mask = mask[12:]
+ }
+ if len(mask) == IPv4len && len(ip) == IPv6len && bytealg.Equal(ip[:12], v4InV6Prefix) {
+ ip = ip[12:]
+ }
+ n := len(ip)
+ if n != len(mask) {
+ return nil
+ }
+ out := make(IP, n)
+ for i := 0; i < n; i++ {
+ out[i] = ip[i] & mask[i]
+ }
+ return out
+}
+
+// String returns the string form of the IP address ip.
+// It returns one of 4 forms:
+// - "", if ip has length 0
+// - dotted decimal ("192.0.2.1"), if ip is an IPv4 or IP4-mapped IPv6 address
+// - IPv6 conforming to RFC 5952 ("2001:db8::1"), if ip is a valid IPv6 address
+// - the hexadecimal form of ip, without punctuation, if no other cases apply
+func (ip IP) String() string {
+ if len(ip) == 0 {
+ return ""
+ }
+
+ if len(ip) != IPv4len && len(ip) != IPv6len {
+ return "?" + hexString(ip)
+ }
+
+ var buf []byte
+ switch len(ip) {
+ case IPv4len:
+ const maxCap = len("255.255.255.255")
+ buf = make([]byte, 0, maxCap)
+ case IPv6len:
+ const maxCap = len("ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff")
+ buf = make([]byte, 0, maxCap)
+ }
+ buf = ip.appendTo(buf)
+ return string(buf)
+}
+
+func hexString(b []byte) string {
+ s := make([]byte, len(b)*2)
+ for i, tn := range b {
+ s[i*2], s[i*2+1] = hexDigit[tn>>4], hexDigit[tn&0xf]
+ }
+ return string(s)
+}
+
+// ipEmptyString is like ip.String except that it returns
+// an empty string when ip is unset.
+func ipEmptyString(ip IP) string {
+ if len(ip) == 0 {
+ return ""
+ }
+ return ip.String()
+}
+
+// appendTo appends the string representation of ip to b and returns the expanded b
+// If len(ip) != IPv4len or IPv6len, it appends nothing.
+func (ip IP) appendTo(b []byte) []byte {
+ // If IPv4, use dotted notation.
+ if p4 := ip.To4(); len(p4) == IPv4len {
+ ip = p4
+ }
+ addr, _ := netip.AddrFromSlice(ip)
+ return addr.AppendTo(b)
+}
+
+// AppendText implements the [encoding.TextAppender] interface.
+// The encoding is the same as returned by [IP.String], with one exception:
+// When len(ip) is zero, it appends nothing.
+func (ip IP) AppendText(b []byte) ([]byte, error) {
+ if len(ip) == 0 {
+ return b, nil
+ }
+ if len(ip) != IPv4len && len(ip) != IPv6len {
+ return b, &AddrError{Err: "invalid IP address", Addr: hexString(ip)}
+ }
+
+ return ip.appendTo(b), nil
+}
+
+// MarshalText implements the [encoding.TextMarshaler] interface.
+// The encoding is the same as returned by [IP.String], with one exception:
+// When len(ip) is zero, it returns an empty slice.
+func (ip IP) MarshalText() ([]byte, error) {
+ // 24 is satisfied with all IPv4 addresses and short IPv6 addresses
+ b, err := ip.AppendText(make([]byte, 0, 24))
+ if err != nil {
+ return nil, err
+ }
+ return b, nil
+}
+
+// UnmarshalText implements the [encoding.TextUnmarshaler] interface.
+// The IP address is expected in a form accepted by [ParseIP].
+func (ip *IP) UnmarshalText(text []byte) error {
+ if len(text) == 0 {
+ *ip = nil
+ return nil
+ }
+ s := string(text)
+ x := ParseIP(s)
+ if x == nil {
+ return &ParseError{Type: "IP address", Text: s}
+ }
+ *ip = x
+ return nil
+}
+
+// Equal reports whether ip and x are the same IP address.
+// An IPv4 address and that same address in IPv6 form are
+// considered to be equal.
+func (ip IP) Equal(x IP) bool {
+ if len(ip) == len(x) {
+ return bytealg.Equal(ip, x)
+ }
+ if len(ip) == IPv4len && len(x) == IPv6len {
+ return bytealg.Equal(x[0:12], v4InV6Prefix) && bytealg.Equal(ip, x[12:])
+ }
+ if len(ip) == IPv6len && len(x) == IPv4len {
+ return bytealg.Equal(ip[0:12], v4InV6Prefix) && bytealg.Equal(ip[12:], x)
+ }
+ return false
+}
+
+func (ip IP) matchAddrFamily(x IP) bool {
+ return ip.To4() != nil && x.To4() != nil || ip.To16() != nil && ip.To4() == nil && x.To16() != nil && x.To4() == nil
+}
+
+// If mask is a sequence of 1 bits followed by 0 bits,
+// return the number of 1 bits.
+func simpleMaskLength(mask IPMask) int {
+ var n int
+ for i, v := range mask {
+ if v == 0xff {
+ n += 8
+ continue
+ }
+ // found non-ff byte
+ // count 1 bits
+ for v&0x80 != 0 {
+ n++
+ v <<= 1
+ }
+ // rest must be 0 bits
+ if v != 0 {
+ return -1
+ }
+ for i++; i < len(mask); i++ {
+ if mask[i] != 0 {
+ return -1
+ }
+ }
+ break
+ }
+ return n
+}
+
+// Size returns the number of leading ones and total bits in the mask.
+// If the mask is not in the canonical form--ones followed by zeros--then
+// Size returns 0, 0.
+func (m IPMask) Size() (ones, bits int) {
+ ones, bits = simpleMaskLength(m), len(m)*8
+ if ones == -1 {
+ return 0, 0
+ }
+ return
+}
+
+// String returns the hexadecimal form of m, with no punctuation.
+func (m IPMask) String() string {
+ if len(m) == 0 {
+ return ""
+ }
+ return hexString(m)
+}
+
+func networkNumberAndMask(n *IPNet) (ip IP, m IPMask) {
+ if ip = n.IP.To4(); ip == nil {
+ ip = n.IP
+ if len(ip) != IPv6len {
+ return nil, nil
+ }
+ }
+ m = n.Mask
+ switch len(m) {
+ case IPv4len:
+ if len(ip) != IPv4len {
+ return nil, nil
+ }
+ case IPv6len:
+ if len(ip) == IPv4len {
+ m = m[12:]
+ }
+ default:
+ return nil, nil
+ }
+ return
+}
+
+// Contains reports whether the network includes ip.
+func (n *IPNet) Contains(ip IP) bool {
+ nn, m := networkNumberAndMask(n)
+ if x := ip.To4(); x != nil {
+ ip = x
+ }
+ l := len(ip)
+ if l != len(nn) {
+ return false
+ }
+ for i := 0; i < l; i++ {
+ if nn[i]&m[i] != ip[i]&m[i] {
+ return false
+ }
+ }
+ return true
+}
+
+// Network returns the address's network name, "ip+net".
+func (n *IPNet) Network() string { return "ip+net" }
+
+// String returns the CIDR notation of n like "192.0.2.0/24"
+// or "2001:db8::/48" as defined in RFC 4632 and RFC 4291.
+// If the mask is not in the canonical form, it returns the
+// string which consists of an IP address, followed by a slash
+// character and a mask expressed as hexadecimal form with no
+// punctuation like "198.51.100.0/c000ff00".
+func (n *IPNet) String() string {
+ if n == nil {
+ return ""
+ }
+ nn, m := networkNumberAndMask(n)
+ if nn == nil || m == nil {
+ return ""
+ }
+ l := simpleMaskLength(m)
+ if l == -1 {
+ return nn.String() + "/" + m.String()
+ }
+ return nn.String() + "/" + strconv.Itoa(l)
+}
+
+// ParseIP parses s as an IP address, returning the result.
+// The string s can be in IPv4 dotted decimal ("192.0.2.1"), IPv6
+// ("2001:db8::68"), or IPv4-mapped IPv6 ("::ffff:192.0.2.1") form.
+// If s is not a valid textual representation of an IP address,
+// ParseIP returns nil. The returned address is always 16 bytes,
+// IPv4 addresses are returned in IPv4-mapped IPv6 form.
+func ParseIP(s string) IP {
+ if addr, valid := parseIP(s); valid {
+ return IP(addr[:])
+ }
+ return nil
+}
+
+func parseIP(s string) ([16]byte, bool) {
+ ip, err := netip.ParseAddr(s)
+ if err != nil || ip.Zone() != "" {
+ return [16]byte{}, false
+ }
+ return ip.As16(), true
+}
+
+// ParseCIDR parses s as a CIDR notation IP address and prefix length,
+// like "192.0.2.0/24" or "2001:db8::/32", as defined in
+// RFC 4632 and RFC 4291.
+//
+// It returns the IP address and the network implied by the IP and
+// prefix length.
+// For example, ParseCIDR("192.0.2.1/24") returns the IP address
+// 192.0.2.1 and the network 192.0.2.0/24.
+func ParseCIDR(s string) (IP, *IPNet, error) {
+ addr, mask, found := stringslite.Cut(s, "/")
+ if !found {
+ return nil, nil, &ParseError{Type: "CIDR address", Text: s}
+ }
+
+ ipAddr, err := netip.ParseAddr(addr)
+ if err != nil || ipAddr.Zone() != "" {
+ return nil, nil, &ParseError{Type: "CIDR address", Text: s}
+ }
+
+ n, i, ok := dtoi(mask)
+ if !ok || i != len(mask) || n < 0 || n > ipAddr.BitLen() {
+ return nil, nil, &ParseError{Type: "CIDR address", Text: s}
+ }
+ m := CIDRMask(n, ipAddr.BitLen())
+ addr16 := ipAddr.As16()
+ return IP(addr16[:]), &IPNet{IP: IP(addr16[:]).Mask(m), Mask: m}, nil
+}
+
+func copyIP(x IP) IP {
+ y := make(IP, len(x))
+ copy(y, x)
+ return y
+}
diff --git a/go/src/net/ip_test.go b/go/src/net/ip_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..55c66fdf31e116903b8d8e90a93bcb41274a9810
--- /dev/null
+++ b/go/src/net/ip_test.go
@@ -0,0 +1,839 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "bytes"
+ "math/rand"
+ "reflect"
+ "runtime"
+ "testing"
+)
+
+var parseIPTests = []struct {
+ in string
+ out IP
+}{
+ {"127.0.1.2", IPv4(127, 0, 1, 2)},
+ {"127.0.0.1", IPv4(127, 0, 0, 1)},
+ {"::ffff:127.1.2.3", IPv4(127, 1, 2, 3)},
+ {"::ffff:7f01:0203", IPv4(127, 1, 2, 3)},
+ {"0:0:0:0:0000:ffff:127.1.2.3", IPv4(127, 1, 2, 3)},
+ {"0:0:0:0::ffff:127.1.2.3", IPv4(127, 1, 2, 3)},
+
+ {"2001:4860:0:2001::68", IP{0x20, 0x01, 0x48, 0x60, 0, 0, 0x20, 0x01, 0, 0, 0, 0, 0, 0, 0x00, 0x68}},
+ {"2001:4860:0000:2001:0000:0000:0000:0068", IP{0x20, 0x01, 0x48, 0x60, 0, 0, 0x20, 0x01, 0, 0, 0, 0, 0, 0, 0x00, 0x68}},
+
+ {"-0.0.0.0", nil},
+ {"0.-1.0.0", nil},
+ {"0.0.-2.0", nil},
+ {"0.0.0.-3", nil},
+ {"127.0.0.256", nil},
+ {"abc", nil},
+ {"123:", nil},
+ {"fe80::1%lo0", nil},
+ {"fe80::1%911", nil},
+ {"", nil},
+ //6 zeroes in one group
+ {"0:0:0:0:000000:ffff:127.1.2.3", nil},
+ //5 zeroes in one group edge case
+ {"0:0:0:0:00000:ffff:127.1.2.3", nil},
+ {"a1:a2:a3:a4::b1:b2:b3:b4", nil}, // Issue 6628
+ {"127.001.002.003", nil},
+ {"::ffff:127.001.002.003", nil},
+ {"123.000.000.000", nil},
+ {"1.2..4", nil},
+ {"0123.0.0.1", nil},
+}
+
+func TestParseIP(t *testing.T) {
+ for _, tt := range parseIPTests {
+ if out := ParseIP(tt.in); !reflect.DeepEqual(out, tt.out) {
+ t.Errorf("ParseIP(%q) = %v, want %v", tt.in, out, tt.out)
+ }
+ if tt.in == "" {
+ // Tested in TestMarshalEmptyIP below.
+ continue
+ }
+ var out IP
+ if err := out.UnmarshalText([]byte(tt.in)); !reflect.DeepEqual(out, tt.out) || (tt.out == nil) != (err != nil) {
+ t.Errorf("IP.UnmarshalText(%q) = %v, %v, want %v", tt.in, out, err, tt.out)
+ }
+ }
+}
+
+func TestLookupWithIP(t *testing.T) {
+ _, err := LookupIP("")
+ if err == nil {
+ t.Errorf(`LookupIP("") succeeded, should fail`)
+ }
+ _, err = LookupHost("")
+ if err == nil {
+ t.Errorf(`LookupIP("") succeeded, should fail`)
+ }
+
+ // Test that LookupHost and LookupIP, which normally
+ // expect host names, work with IP addresses.
+ for _, tt := range parseIPTests {
+ if tt.out != nil {
+ addrs, err := LookupHost(tt.in)
+ if len(addrs) != 1 || addrs[0] != tt.in || err != nil {
+ t.Errorf("LookupHost(%q) = %v, %v, want %v, nil", tt.in, addrs, err, []string{tt.in})
+ }
+ } else if !testing.Short() {
+ // We can't control what the host resolver does; if it can resolve, say,
+ // 127.0.0.256 or fe80::1%911 or a host named 'abc', who are we to judge?
+ // Warn about these discrepancies but don't fail the test.
+ addrs, err := LookupHost(tt.in)
+ if err == nil {
+ t.Logf("warning: LookupHost(%q) = %v, want error", tt.in, addrs)
+ }
+ }
+
+ if tt.out != nil {
+ ips, err := LookupIP(tt.in)
+ if len(ips) != 1 || !reflect.DeepEqual(ips[0], tt.out) || err != nil {
+ t.Errorf("LookupIP(%q) = %v, %v, want %v, nil", tt.in, ips, err, []IP{tt.out})
+ }
+ } else if !testing.Short() {
+ ips, err := LookupIP(tt.in)
+ // We can't control what the host resolver does. See above.
+ if err == nil {
+ t.Logf("warning: LookupIP(%q) = %v, want error", tt.in, ips)
+ }
+ }
+ }
+}
+
+func BenchmarkParseIP(b *testing.B) {
+ testHookUninstaller.Do(uninstallTestHooks)
+
+ for i := 0; i < b.N; i++ {
+ for _, tt := range parseIPTests {
+ ParseIP(tt.in)
+ }
+ }
+}
+
+func BenchmarkParseIPValidIPv4(b *testing.B) {
+ testHookUninstaller.Do(uninstallTestHooks)
+
+ for i := 0; i < b.N; i++ {
+ ParseIP("192.0.2.1")
+ }
+}
+
+func BenchmarkParseIPValidIPv6(b *testing.B) {
+ testHookUninstaller.Do(uninstallTestHooks)
+
+ for i := 0; i < b.N; i++ {
+ ParseIP("2001:DB8::1")
+ }
+}
+
+// Issue 6339
+func TestMarshalEmptyIP(t *testing.T) {
+ for _, in := range [][]byte{nil, []byte("")} {
+ var out = IP{1, 2, 3, 4}
+ if err := out.UnmarshalText(in); err != nil || out != nil {
+ t.Errorf("UnmarshalText(%v) = %v, %v; want nil, nil", in, out, err)
+ }
+ }
+ var ip IP
+ got, err := ip.MarshalText()
+ if err != nil {
+ t.Fatal(err)
+ }
+ if !reflect.DeepEqual(got, []byte("")) {
+ t.Errorf(`got %#v, want []byte("")`, got)
+ }
+
+ buf := make([]byte, 4)
+ got, err = ip.AppendText(buf)
+ if err != nil {
+ t.Fatal(err)
+ }
+ if !reflect.DeepEqual(got, []byte("\x00\x00\x00\x00")) {
+ t.Errorf(`got %#v, want []byte("\x00\x00\x00\x00")`, got)
+ }
+}
+
+var ipStringTests = []*struct {
+ in IP // see RFC 791 and RFC 4291
+ str string // see RFC 791, RFC 4291 and RFC 5952
+ byt []byte
+ error
+}{
+ // IPv4 address
+ {
+ IP{192, 0, 2, 1},
+ "192.0.2.1",
+ []byte("192.0.2.1"),
+ nil,
+ },
+ {
+ IP{0, 0, 0, 0},
+ "0.0.0.0",
+ []byte("0.0.0.0"),
+ nil,
+ },
+
+ // IPv4-mapped IPv6 address
+ {
+ IP{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xff, 0xff, 192, 0, 2, 1},
+ "192.0.2.1",
+ []byte("192.0.2.1"),
+ nil,
+ },
+ {
+ IP{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xff, 0xff, 0, 0, 0, 0},
+ "0.0.0.0",
+ []byte("0.0.0.0"),
+ nil,
+ },
+
+ // IPv6 address
+ {
+ IP{0x20, 0x1, 0xd, 0xb8, 0, 0, 0, 0, 0, 0, 0x1, 0x23, 0, 0x12, 0, 0x1},
+ "2001:db8::123:12:1",
+ []byte("2001:db8::123:12:1"),
+ nil,
+ },
+ {
+ IP{0x20, 0x1, 0xd, 0xb8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x1},
+ "2001:db8::1",
+ []byte("2001:db8::1"),
+ nil,
+ },
+ {
+ IP{0x20, 0x1, 0xd, 0xb8, 0, 0, 0, 0x1, 0, 0, 0, 0x1, 0, 0, 0, 0x1},
+ "2001:db8:0:1:0:1:0:1",
+ []byte("2001:db8:0:1:0:1:0:1"),
+ nil,
+ },
+ {
+ IP{0x20, 0x1, 0xd, 0xb8, 0, 0x1, 0, 0, 0, 0x1, 0, 0, 0, 0x1, 0, 0},
+ "2001:db8:1:0:1:0:1:0",
+ []byte("2001:db8:1:0:1:0:1:0"),
+ nil,
+ },
+ {
+ IP{0x20, 0x1, 0, 0, 0, 0, 0, 0, 0, 0x1, 0, 0, 0, 0, 0, 0x1},
+ "2001::1:0:0:1",
+ []byte("2001::1:0:0:1"),
+ nil,
+ },
+ {
+ IP{0x20, 0x1, 0xd, 0xb8, 0, 0, 0, 0, 0, 0x1, 0, 0, 0, 0, 0, 0},
+ "2001:db8:0:0:1::",
+ []byte("2001:db8:0:0:1::"),
+ nil,
+ },
+ {
+ IP{0x20, 0x1, 0xd, 0xb8, 0, 0, 0, 0, 0, 0x1, 0, 0, 0, 0, 0, 0x1},
+ "2001:db8::1:0:0:1",
+ []byte("2001:db8::1:0:0:1"),
+ nil,
+ },
+ {
+ IP{0x20, 0x1, 0xd, 0xb8, 0, 0, 0, 0, 0, 0xa, 0, 0xb, 0, 0xc, 0, 0xd},
+ "2001:db8::a:b:c:d",
+ []byte("2001:db8::a:b:c:d"),
+ nil,
+ },
+ {
+ IPv6unspecified,
+ "::",
+ []byte("::"),
+ nil,
+ },
+
+ // IP wildcard equivalent address in Dial/Listen API
+ {
+ nil,
+ "",
+ nil,
+ nil,
+ },
+
+ // Opaque byte sequence
+ {
+ IP{0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef},
+ "?0123456789abcdef",
+ nil,
+ &AddrError{Err: "invalid IP address", Addr: "0123456789abcdef"},
+ },
+}
+
+func TestIPString(t *testing.T) {
+ for _, tt := range ipStringTests {
+ if out := tt.in.String(); out != tt.str {
+ t.Errorf("IP.String(%v) = %q, want %q", tt.in, out, tt.str)
+ }
+ if out, err := tt.in.MarshalText(); !bytes.Equal(out, tt.byt) || !reflect.DeepEqual(err, tt.error) {
+ t.Errorf("IP.MarshalText(%v) = %v, %v, want %v, %v", tt.in, out, err, tt.byt, tt.error)
+ }
+ buf := make([]byte, 4, 32)
+ if out, err := tt.in.AppendText(buf); !bytes.Equal(out[4:], tt.byt) || !reflect.DeepEqual(err, tt.error) {
+ t.Errorf("IP.AppendText(%v) = %v, %v, want %v, %v", tt.in, out[4:], err, tt.byt, tt.error)
+ }
+ }
+}
+
+func TestIPAppendTextNoAllocs(t *testing.T) {
+ // except the invalid IP
+ for _, tt := range ipStringTests[:len(ipStringTests)-1] {
+ allocs := int(testing.AllocsPerRun(1000, func() {
+ buf := make([]byte, 0, 64)
+ _, _ = tt.in.AppendText(buf)
+ }))
+ if allocs != 0 {
+ t.Errorf("IP(%q) AppendText allocs: %d times, want 0", tt.in, allocs)
+ }
+ }
+}
+
+func BenchmarkIPMarshalText(b *testing.B) {
+ b.Run("IPv4", func(b *testing.B) {
+ b.ReportAllocs()
+ b.ResetTimer()
+ ip := IP{192, 0, 2, 1}
+ for range b.N {
+ _, _ = ip.MarshalText()
+ }
+ })
+ b.Run("IPv6", func(b *testing.B) {
+ b.ReportAllocs()
+ b.ResetTimer()
+ ip := IP{0x20, 0x1, 0xd, 0xb8, 0, 0, 0, 0, 0, 0xa, 0, 0xb, 0, 0xc, 0, 0xd}
+ for range b.N {
+ _, _ = ip.MarshalText()
+ }
+ })
+ b.Run("IPv6_long", func(b *testing.B) {
+ b.ReportAllocs()
+ b.ResetTimer()
+ // fd7a:115c:a1e0:ab12:4843:cd96:626b:430b
+ ip := IP{253, 122, 17, 92, 161, 224, 171, 18, 72, 67, 205, 150, 98, 107, 67, 11}
+ for range b.N {
+ _, _ = ip.MarshalText()
+ }
+ })
+}
+
+var sink string
+
+func BenchmarkIPString(b *testing.B) {
+ testHookUninstaller.Do(uninstallTestHooks)
+
+ b.Run("IPv4", func(b *testing.B) {
+ benchmarkIPString(b, IPv4len)
+ })
+
+ b.Run("IPv6", func(b *testing.B) {
+ benchmarkIPString(b, IPv6len)
+ })
+}
+
+func benchmarkIPString(b *testing.B, size int) {
+ b.ReportAllocs()
+ b.ResetTimer()
+ for i := 0; i < b.N; i++ {
+ for _, tt := range ipStringTests {
+ if tt.in != nil && len(tt.in) == size {
+ sink = tt.in.String()
+ }
+ }
+ }
+}
+
+var ipMaskTests = []struct {
+ in IP
+ mask IPMask
+ out IP
+}{
+ {IPv4(192, 168, 1, 127), IPv4Mask(255, 255, 255, 128), IPv4(192, 168, 1, 0)},
+ {IPv4(192, 168, 1, 127), IPMask(ParseIP("255.255.255.192")), IPv4(192, 168, 1, 64)},
+ {IPv4(192, 168, 1, 127), IPMask(ParseIP("ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffe0")), IPv4(192, 168, 1, 96)},
+ {IPv4(192, 168, 1, 127), IPv4Mask(255, 0, 255, 0), IPv4(192, 0, 1, 0)},
+ {ParseIP("2001:db8::1"), IPMask(ParseIP("ffff:ff80::")), ParseIP("2001:d80::")},
+ {ParseIP("2001:db8::1"), IPMask(ParseIP("f0f0:0f0f::")), ParseIP("2000:d08::")},
+}
+
+func TestIPMask(t *testing.T) {
+ for _, tt := range ipMaskTests {
+ if out := tt.in.Mask(tt.mask); out == nil || !tt.out.Equal(out) {
+ t.Errorf("IP(%v).Mask(%v) = %v, want %v", tt.in, tt.mask, out, tt.out)
+ }
+ }
+}
+
+var ipMaskStringTests = []struct {
+ in IPMask
+ out string
+}{
+ {IPv4Mask(255, 255, 255, 240), "fffffff0"},
+ {IPv4Mask(255, 0, 128, 0), "ff008000"},
+ {IPMask(ParseIP("ffff:ff80::")), "ffffff80000000000000000000000000"},
+ {IPMask(ParseIP("ef00:ff80::cafe:0")), "ef00ff800000000000000000cafe0000"},
+ {nil, ""},
+}
+
+func TestIPMaskString(t *testing.T) {
+ for _, tt := range ipMaskStringTests {
+ if out := tt.in.String(); out != tt.out {
+ t.Errorf("IPMask.String(%v) = %q, want %q", tt.in, out, tt.out)
+ }
+ }
+}
+
+func BenchmarkIPMaskString(b *testing.B) {
+ testHookUninstaller.Do(uninstallTestHooks)
+
+ for i := 0; i < b.N; i++ {
+ for _, tt := range ipMaskStringTests {
+ sink = tt.in.String()
+ }
+ }
+}
+
+var parseCIDRTests = []struct {
+ in string
+ ip IP
+ net *IPNet
+ err error
+}{
+ {"135.104.0.0/32", IPv4(135, 104, 0, 0), &IPNet{IP: IPv4(135, 104, 0, 0), Mask: IPv4Mask(255, 255, 255, 255)}, nil},
+ {"0.0.0.0/24", IPv4(0, 0, 0, 0), &IPNet{IP: IPv4(0, 0, 0, 0), Mask: IPv4Mask(255, 255, 255, 0)}, nil},
+ {"135.104.0.0/24", IPv4(135, 104, 0, 0), &IPNet{IP: IPv4(135, 104, 0, 0), Mask: IPv4Mask(255, 255, 255, 0)}, nil},
+ {"135.104.0.1/32", IPv4(135, 104, 0, 1), &IPNet{IP: IPv4(135, 104, 0, 1), Mask: IPv4Mask(255, 255, 255, 255)}, nil},
+ {"135.104.0.1/24", IPv4(135, 104, 0, 1), &IPNet{IP: IPv4(135, 104, 0, 0), Mask: IPv4Mask(255, 255, 255, 0)}, nil},
+ {"::1/128", ParseIP("::1"), &IPNet{IP: ParseIP("::1"), Mask: IPMask(ParseIP("ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff"))}, nil},
+ {"abcd:2345::/127", ParseIP("abcd:2345::"), &IPNet{IP: ParseIP("abcd:2345::"), Mask: IPMask(ParseIP("ffff:ffff:ffff:ffff:ffff:ffff:ffff:fffe"))}, nil},
+ {"abcd:2345::/65", ParseIP("abcd:2345::"), &IPNet{IP: ParseIP("abcd:2345::"), Mask: IPMask(ParseIP("ffff:ffff:ffff:ffff:8000::"))}, nil},
+ {"abcd:2345::/64", ParseIP("abcd:2345::"), &IPNet{IP: ParseIP("abcd:2345::"), Mask: IPMask(ParseIP("ffff:ffff:ffff:ffff::"))}, nil},
+ {"abcd:2345::/63", ParseIP("abcd:2345::"), &IPNet{IP: ParseIP("abcd:2345::"), Mask: IPMask(ParseIP("ffff:ffff:ffff:fffe::"))}, nil},
+ {"abcd:2345::/33", ParseIP("abcd:2345::"), &IPNet{IP: ParseIP("abcd:2345::"), Mask: IPMask(ParseIP("ffff:ffff:8000::"))}, nil},
+ {"abcd:2345::/32", ParseIP("abcd:2345::"), &IPNet{IP: ParseIP("abcd:2345::"), Mask: IPMask(ParseIP("ffff:ffff::"))}, nil},
+ {"abcd:2344::/31", ParseIP("abcd:2344::"), &IPNet{IP: ParseIP("abcd:2344::"), Mask: IPMask(ParseIP("ffff:fffe::"))}, nil},
+ {"abcd:2300::/24", ParseIP("abcd:2300::"), &IPNet{IP: ParseIP("abcd:2300::"), Mask: IPMask(ParseIP("ffff:ff00::"))}, nil},
+ {"abcd:2345::/24", ParseIP("abcd:2345::"), &IPNet{IP: ParseIP("abcd:2300::"), Mask: IPMask(ParseIP("ffff:ff00::"))}, nil},
+ {"2001:DB8::/48", ParseIP("2001:DB8::"), &IPNet{IP: ParseIP("2001:DB8::"), Mask: IPMask(ParseIP("ffff:ffff:ffff::"))}, nil},
+ {"2001:DB8::1/48", ParseIP("2001:DB8::1"), &IPNet{IP: ParseIP("2001:DB8::"), Mask: IPMask(ParseIP("ffff:ffff:ffff::"))}, nil},
+ {"192.168.1.1/255.255.255.0", nil, nil, &ParseError{Type: "CIDR address", Text: "192.168.1.1/255.255.255.0"}},
+ {"192.168.1.1/35", nil, nil, &ParseError{Type: "CIDR address", Text: "192.168.1.1/35"}},
+ {"2001:db8::1/-1", nil, nil, &ParseError{Type: "CIDR address", Text: "2001:db8::1/-1"}},
+ {"2001:db8::1/-0", nil, nil, &ParseError{Type: "CIDR address", Text: "2001:db8::1/-0"}},
+ {"-0.0.0.0/32", nil, nil, &ParseError{Type: "CIDR address", Text: "-0.0.0.0/32"}},
+ {"0.-1.0.0/32", nil, nil, &ParseError{Type: "CIDR address", Text: "0.-1.0.0/32"}},
+ {"0.0.-2.0/32", nil, nil, &ParseError{Type: "CIDR address", Text: "0.0.-2.0/32"}},
+ {"0.0.0.-3/32", nil, nil, &ParseError{Type: "CIDR address", Text: "0.0.0.-3/32"}},
+ {"0.0.0.0/-0", nil, nil, &ParseError{Type: "CIDR address", Text: "0.0.0.0/-0"}},
+ {"127.000.000.001/32", nil, nil, &ParseError{Type: "CIDR address", Text: "127.000.000.001/32"}},
+ {"", nil, nil, &ParseError{Type: "CIDR address", Text: ""}},
+}
+
+func TestParseCIDR(t *testing.T) {
+ for _, tt := range parseCIDRTests {
+ ip, net, err := ParseCIDR(tt.in)
+ if !reflect.DeepEqual(err, tt.err) {
+ t.Errorf("ParseCIDR(%q) = %v, %v; want %v, %v", tt.in, ip, net, tt.ip, tt.net)
+ }
+ if err == nil && (!tt.ip.Equal(ip) || !tt.net.IP.Equal(net.IP) || !reflect.DeepEqual(net.Mask, tt.net.Mask)) {
+ t.Errorf("ParseCIDR(%q) = %v, {%v, %v}; want %v, {%v, %v}", tt.in, ip, net.IP, net.Mask, tt.ip, tt.net.IP, tt.net.Mask)
+ }
+ }
+}
+
+var ipNetContainsTests = []struct {
+ ip IP
+ net *IPNet
+ ok bool
+}{
+ {IPv4(172, 16, 1, 1), &IPNet{IP: IPv4(172, 16, 0, 0), Mask: CIDRMask(12, 32)}, true},
+ {IPv4(172, 24, 0, 1), &IPNet{IP: IPv4(172, 16, 0, 0), Mask: CIDRMask(13, 32)}, false},
+ {IPv4(192, 168, 0, 3), &IPNet{IP: IPv4(192, 168, 0, 0), Mask: IPv4Mask(0, 0, 255, 252)}, true},
+ {IPv4(192, 168, 0, 4), &IPNet{IP: IPv4(192, 168, 0, 0), Mask: IPv4Mask(0, 255, 0, 252)}, false},
+ {ParseIP("2001:db8:1:2::1"), &IPNet{IP: ParseIP("2001:db8:1::"), Mask: CIDRMask(47, 128)}, true},
+ {ParseIP("2001:db8:1:2::1"), &IPNet{IP: ParseIP("2001:db8:2::"), Mask: CIDRMask(47, 128)}, false},
+ {ParseIP("2001:db8:1:2::1"), &IPNet{IP: ParseIP("2001:db8:1::"), Mask: IPMask(ParseIP("ffff:0:ffff::"))}, true},
+ {ParseIP("2001:db8:1:2::1"), &IPNet{IP: ParseIP("2001:db8:1::"), Mask: IPMask(ParseIP("0:0:0:ffff::"))}, false},
+}
+
+func TestIPNetContains(t *testing.T) {
+ for _, tt := range ipNetContainsTests {
+ if ok := tt.net.Contains(tt.ip); ok != tt.ok {
+ t.Errorf("IPNet(%v).Contains(%v) = %v, want %v", tt.net, tt.ip, ok, tt.ok)
+ }
+ }
+}
+
+var ipNetStringTests = []struct {
+ in *IPNet
+ out string
+}{
+ {&IPNet{IP: IPv4(192, 168, 1, 0), Mask: CIDRMask(26, 32)}, "192.168.1.0/26"},
+ {&IPNet{IP: IPv4(192, 168, 1, 0), Mask: IPv4Mask(255, 0, 255, 0)}, "192.168.1.0/ff00ff00"},
+ {&IPNet{IP: ParseIP("2001:db8::"), Mask: CIDRMask(55, 128)}, "2001:db8::/55"},
+ {&IPNet{IP: ParseIP("2001:db8::"), Mask: IPMask(ParseIP("8000:f123:0:cafe::"))}, "2001:db8::/8000f1230000cafe0000000000000000"},
+ {nil, ""},
+}
+
+func TestIPNetString(t *testing.T) {
+ for _, tt := range ipNetStringTests {
+ if out := tt.in.String(); out != tt.out {
+ t.Errorf("IPNet.String(%v) = %q, want %q", tt.in, out, tt.out)
+ }
+ }
+}
+
+var cidrMaskTests = []struct {
+ ones int
+ bits int
+ out IPMask
+}{
+ {0, 32, IPv4Mask(0, 0, 0, 0)},
+ {12, 32, IPv4Mask(255, 240, 0, 0)},
+ {24, 32, IPv4Mask(255, 255, 255, 0)},
+ {32, 32, IPv4Mask(255, 255, 255, 255)},
+ {0, 128, IPMask{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}},
+ {4, 128, IPMask{0xf0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}},
+ {48, 128, IPMask{0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}},
+ {128, 128, IPMask{0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff}},
+ {33, 32, nil},
+ {32, 33, nil},
+ {-1, 128, nil},
+ {128, -1, nil},
+}
+
+func TestCIDRMask(t *testing.T) {
+ for _, tt := range cidrMaskTests {
+ if out := CIDRMask(tt.ones, tt.bits); !reflect.DeepEqual(out, tt.out) {
+ t.Errorf("CIDRMask(%v, %v) = %v, want %v", tt.ones, tt.bits, out, tt.out)
+ }
+ }
+}
+
+var (
+ v4addr = IP{192, 168, 0, 1}
+ v4mappedv6addr = IP{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xff, 0xff, 192, 168, 0, 1}
+ v6addr = IP{0x20, 0x1, 0xd, 0xb8, 0, 0, 0, 0, 0, 0, 0x1, 0x23, 0, 0x12, 0, 0x1}
+ v4mask = IPMask{255, 255, 255, 0}
+ v4mappedv6mask = IPMask{0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 255, 255, 255, 0}
+ v6mask = IPMask{0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0, 0, 0, 0, 0, 0, 0, 0}
+ badaddr = IP{192, 168, 0}
+ badmask = IPMask{255, 255, 0}
+ v4maskzero = IPMask{0, 0, 0, 0}
+)
+
+var networkNumberAndMaskTests = []struct {
+ in IPNet
+ out IPNet
+}{
+ {IPNet{IP: v4addr, Mask: v4mask}, IPNet{IP: v4addr, Mask: v4mask}},
+ {IPNet{IP: v4addr, Mask: v4mappedv6mask}, IPNet{IP: v4addr, Mask: v4mask}},
+ {IPNet{IP: v4mappedv6addr, Mask: v4mappedv6mask}, IPNet{IP: v4addr, Mask: v4mask}},
+ {IPNet{IP: v4mappedv6addr, Mask: v6mask}, IPNet{IP: v4addr, Mask: v4maskzero}},
+ {IPNet{IP: v4addr, Mask: v6mask}, IPNet{IP: v4addr, Mask: v4maskzero}},
+ {IPNet{IP: v6addr, Mask: v6mask}, IPNet{IP: v6addr, Mask: v6mask}},
+ {IPNet{IP: v6addr, Mask: v4mappedv6mask}, IPNet{IP: v6addr, Mask: v4mappedv6mask}},
+ {in: IPNet{IP: v6addr, Mask: v4mask}},
+ {in: IPNet{IP: v4addr, Mask: badmask}},
+ {in: IPNet{IP: v4mappedv6addr, Mask: badmask}},
+ {in: IPNet{IP: v6addr, Mask: badmask}},
+ {in: IPNet{IP: badaddr, Mask: v4mask}},
+ {in: IPNet{IP: badaddr, Mask: v4mappedv6mask}},
+ {in: IPNet{IP: badaddr, Mask: v6mask}},
+ {in: IPNet{IP: badaddr, Mask: badmask}},
+}
+
+func TestNetworkNumberAndMask(t *testing.T) {
+ for _, tt := range networkNumberAndMaskTests {
+ ip, m := networkNumberAndMask(&tt.in)
+ out := &IPNet{IP: ip, Mask: m}
+ if !reflect.DeepEqual(&tt.out, out) {
+ t.Errorf("networkNumberAndMask(%v) = %v, want %v", tt.in, out, &tt.out)
+ }
+ }
+}
+
+func TestSplitHostPort(t *testing.T) {
+ for _, tt := range []struct {
+ hostPort string
+ host string
+ port string
+ }{
+ // Host name
+ {"localhost:http", "localhost", "http"},
+ {"localhost:80", "localhost", "80"},
+
+ // Go-specific host name with zone identifier
+ {"localhost%lo0:http", "localhost%lo0", "http"},
+ {"localhost%lo0:80", "localhost%lo0", "80"},
+ {"[localhost%lo0]:http", "localhost%lo0", "http"}, // Go 1 behavior
+ {"[localhost%lo0]:80", "localhost%lo0", "80"}, // Go 1 behavior
+
+ // IP literal
+ {"127.0.0.1:http", "127.0.0.1", "http"},
+ {"127.0.0.1:80", "127.0.0.1", "80"},
+ {"[::1]:http", "::1", "http"},
+ {"[::1]:80", "::1", "80"},
+
+ // IP literal with zone identifier
+ {"[::1%lo0]:http", "::1%lo0", "http"},
+ {"[::1%lo0]:80", "::1%lo0", "80"},
+
+ // Go-specific wildcard for host name
+ {":http", "", "http"}, // Go 1 behavior
+ {":80", "", "80"}, // Go 1 behavior
+
+ // Go-specific wildcard for service name or transport port number
+ {"golang.org:", "golang.org", ""}, // Go 1 behavior
+ {"127.0.0.1:", "127.0.0.1", ""}, // Go 1 behavior
+ {"[::1]:", "::1", ""}, // Go 1 behavior
+
+ // Opaque service name
+ {"golang.org:https%foo", "golang.org", "https%foo"}, // Go 1 behavior
+ } {
+ if host, port, err := SplitHostPort(tt.hostPort); host != tt.host || port != tt.port || err != nil {
+ t.Errorf("SplitHostPort(%q) = %q, %q, %v; want %q, %q, nil", tt.hostPort, host, port, err, tt.host, tt.port)
+ }
+ }
+
+ for _, tt := range []struct {
+ hostPort string
+ err string
+ }{
+ {"golang.org", "missing port in address"},
+ {"127.0.0.1", "missing port in address"},
+ {"[::1]", "missing port in address"},
+ {"[fe80::1%lo0]", "missing port in address"},
+ {"[localhost%lo0]", "missing port in address"},
+ {"localhost%lo0", "missing port in address"},
+
+ {"::1", "too many colons in address"},
+ {"fe80::1%lo0", "too many colons in address"},
+ {"fe80::1%lo0:80", "too many colons in address"},
+
+ // Test cases that didn't fail in Go 1
+
+ {"[foo:bar]", "missing port in address"},
+ {"[foo:bar]baz", "missing port in address"},
+ {"[foo]bar:baz", "missing port in address"},
+
+ {"[foo]:[bar]:baz", "too many colons in address"},
+
+ {"[foo]:[bar]baz", "unexpected '[' in address"},
+ {"foo[bar]:baz", "unexpected '[' in address"},
+
+ {"foo]bar:baz", "unexpected ']' in address"},
+ } {
+ if host, port, err := SplitHostPort(tt.hostPort); err == nil {
+ t.Errorf("SplitHostPort(%q) should have failed", tt.hostPort)
+ } else {
+ e := err.(*AddrError)
+ if e.Err != tt.err {
+ t.Errorf("SplitHostPort(%q) = _, _, %q; want %q", tt.hostPort, e.Err, tt.err)
+ }
+ if host != "" || port != "" {
+ t.Errorf("SplitHostPort(%q) = %q, %q, err; want %q, %q, err on failure", tt.hostPort, host, port, "", "")
+ }
+ }
+ }
+}
+
+func TestJoinHostPort(t *testing.T) {
+ for _, tt := range []struct {
+ host string
+ port string
+ hostPort string
+ }{
+ // Host name
+ {"localhost", "http", "localhost:http"},
+ {"localhost", "80", "localhost:80"},
+
+ // Go-specific host name with zone identifier
+ {"localhost%lo0", "http", "localhost%lo0:http"},
+ {"localhost%lo0", "80", "localhost%lo0:80"},
+
+ // IP literal
+ {"127.0.0.1", "http", "127.0.0.1:http"},
+ {"127.0.0.1", "80", "127.0.0.1:80"},
+ {"::1", "http", "[::1]:http"},
+ {"::1", "80", "[::1]:80"},
+
+ // IP literal with zone identifier
+ {"::1%lo0", "http", "[::1%lo0]:http"},
+ {"::1%lo0", "80", "[::1%lo0]:80"},
+
+ // Go-specific wildcard for host name
+ {"", "http", ":http"}, // Go 1 behavior
+ {"", "80", ":80"}, // Go 1 behavior
+
+ // Go-specific wildcard for service name or transport port number
+ {"golang.org", "", "golang.org:"}, // Go 1 behavior
+ {"127.0.0.1", "", "127.0.0.1:"}, // Go 1 behavior
+ {"::1", "", "[::1]:"}, // Go 1 behavior
+
+ // Opaque service name
+ {"golang.org", "https%foo", "golang.org:https%foo"}, // Go 1 behavior
+ } {
+ if hostPort := JoinHostPort(tt.host, tt.port); hostPort != tt.hostPort {
+ t.Errorf("JoinHostPort(%q, %q) = %q; want %q", tt.host, tt.port, hostPort, tt.hostPort)
+ }
+ }
+}
+
+var ipAddrFamilyTests = []struct {
+ in IP
+ af4 bool
+ af6 bool
+}{
+ {IPv4bcast, true, false},
+ {IPv4allsys, true, false},
+ {IPv4allrouter, true, false},
+ {IPv4zero, true, false},
+ {IPv4(224, 0, 0, 1), true, false},
+ {IPv4(127, 0, 0, 1), true, false},
+ {IPv4(240, 0, 0, 1), true, false},
+ {IPv6unspecified, false, true},
+ {IPv6loopback, false, true},
+ {IPv6interfacelocalallnodes, false, true},
+ {IPv6linklocalallnodes, false, true},
+ {IPv6linklocalallrouters, false, true},
+ {ParseIP("ff05::a:b:c:d"), false, true},
+ {ParseIP("fe80::1:2:3:4"), false, true},
+ {ParseIP("2001:db8::123:12:1"), false, true},
+}
+
+func TestIPAddrFamily(t *testing.T) {
+ for _, tt := range ipAddrFamilyTests {
+ if af := tt.in.To4() != nil; af != tt.af4 {
+ t.Errorf("verifying IPv4 address family for %q = %v, want %v", tt.in, af, tt.af4)
+ }
+ if af := len(tt.in) == IPv6len && tt.in.To4() == nil; af != tt.af6 {
+ t.Errorf("verifying IPv6 address family for %q = %v, want %v", tt.in, af, tt.af6)
+ }
+ }
+}
+
+var ipAddrScopeTests = []struct {
+ scope func(IP) bool
+ in IP
+ ok bool
+}{
+ {IP.IsUnspecified, IPv4zero, true},
+ {IP.IsUnspecified, IPv4(127, 0, 0, 1), false},
+ {IP.IsUnspecified, IPv6unspecified, true},
+ {IP.IsUnspecified, IPv6interfacelocalallnodes, false},
+ {IP.IsUnspecified, nil, false},
+ {IP.IsLoopback, IPv4(127, 0, 0, 1), true},
+ {IP.IsLoopback, IPv4(127, 255, 255, 254), true},
+ {IP.IsLoopback, IPv4(128, 1, 2, 3), false},
+ {IP.IsLoopback, IPv6loopback, true},
+ {IP.IsLoopback, IPv6linklocalallrouters, false},
+ {IP.IsLoopback, nil, false},
+ {IP.IsMulticast, IPv4(224, 0, 0, 0), true},
+ {IP.IsMulticast, IPv4(239, 0, 0, 0), true},
+ {IP.IsMulticast, IPv4(240, 0, 0, 0), false},
+ {IP.IsMulticast, IPv6linklocalallnodes, true},
+ {IP.IsMulticast, IP{0xff, 0x05, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, true},
+ {IP.IsMulticast, IP{0xfe, 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, false},
+ {IP.IsMulticast, nil, false},
+ {IP.IsInterfaceLocalMulticast, IPv4(224, 0, 0, 0), false},
+ {IP.IsInterfaceLocalMulticast, IPv4(0xff, 0x01, 0, 0), false},
+ {IP.IsInterfaceLocalMulticast, IPv6interfacelocalallnodes, true},
+ {IP.IsInterfaceLocalMulticast, nil, false},
+ {IP.IsLinkLocalMulticast, IPv4(224, 0, 0, 0), true},
+ {IP.IsLinkLocalMulticast, IPv4(239, 0, 0, 0), false},
+ {IP.IsLinkLocalMulticast, IPv4(0xff, 0x02, 0, 0), false},
+ {IP.IsLinkLocalMulticast, IPv6linklocalallrouters, true},
+ {IP.IsLinkLocalMulticast, IP{0xff, 0x05, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, false},
+ {IP.IsLinkLocalMulticast, nil, false},
+ {IP.IsLinkLocalUnicast, IPv4(169, 254, 0, 0), true},
+ {IP.IsLinkLocalUnicast, IPv4(169, 255, 0, 0), false},
+ {IP.IsLinkLocalUnicast, IPv4(0xfe, 0x80, 0, 0), false},
+ {IP.IsLinkLocalUnicast, IP{0xfe, 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, true},
+ {IP.IsLinkLocalUnicast, IP{0xfe, 0xc0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, false},
+ {IP.IsLinkLocalUnicast, nil, false},
+ {IP.IsGlobalUnicast, IPv4(240, 0, 0, 0), true},
+ {IP.IsGlobalUnicast, IPv4(232, 0, 0, 0), false},
+ {IP.IsGlobalUnicast, IPv4(169, 254, 0, 0), false},
+ {IP.IsGlobalUnicast, IPv4bcast, false},
+ {IP.IsGlobalUnicast, IP{0x20, 0x1, 0xd, 0xb8, 0, 0, 0, 0, 0, 0, 0x1, 0x23, 0, 0x12, 0, 0x1}, true},
+ {IP.IsGlobalUnicast, IP{0xfe, 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, false},
+ {IP.IsGlobalUnicast, IP{0xff, 0x05, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, false},
+ {IP.IsGlobalUnicast, nil, false},
+ {IP.IsPrivate, nil, false},
+ {IP.IsPrivate, IPv4(1, 1, 1, 1), false},
+ {IP.IsPrivate, IPv4(9, 255, 255, 255), false},
+ {IP.IsPrivate, IPv4(10, 0, 0, 0), true},
+ {IP.IsPrivate, IPv4(10, 255, 255, 255), true},
+ {IP.IsPrivate, IPv4(11, 0, 0, 0), false},
+ {IP.IsPrivate, IPv4(172, 15, 255, 255), false},
+ {IP.IsPrivate, IPv4(172, 16, 0, 0), true},
+ {IP.IsPrivate, IPv4(172, 16, 255, 255), true},
+ {IP.IsPrivate, IPv4(172, 23, 18, 255), true},
+ {IP.IsPrivate, IPv4(172, 31, 255, 255), true},
+ {IP.IsPrivate, IPv4(172, 31, 0, 0), true},
+ {IP.IsPrivate, IPv4(172, 32, 0, 0), false},
+ {IP.IsPrivate, IPv4(192, 167, 255, 255), false},
+ {IP.IsPrivate, IPv4(192, 168, 0, 0), true},
+ {IP.IsPrivate, IPv4(192, 168, 255, 255), true},
+ {IP.IsPrivate, IPv4(192, 169, 0, 0), false},
+ {IP.IsPrivate, IP{0xfb, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff}, false},
+ {IP.IsPrivate, IP{0xfc, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, true},
+ {IP.IsPrivate, IP{0xfc, 0xff, 0x12, 0, 0, 0, 0, 0x44, 0, 0, 0, 0, 0, 0, 0, 0}, true},
+ {IP.IsPrivate, IP{0xfd, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff}, true},
+ {IP.IsPrivate, IP{0xfe, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, false},
+}
+
+func name(f any) string {
+ return runtime.FuncForPC(reflect.ValueOf(f).Pointer()).Name()
+}
+
+func TestIPAddrScope(t *testing.T) {
+ for _, tt := range ipAddrScopeTests {
+ if ok := tt.scope(tt.in); ok != tt.ok {
+ t.Errorf("%s(%q) = %v, want %v", name(tt.scope), tt.in, ok, tt.ok)
+ }
+ ip := tt.in.To4()
+ if ip == nil {
+ continue
+ }
+ if ok := tt.scope(ip); ok != tt.ok {
+ t.Errorf("%s(%q) = %v, want %v", name(tt.scope), ip, ok, tt.ok)
+ }
+ }
+}
+
+func BenchmarkIPEqual(b *testing.B) {
+ b.Run("IPv4", func(b *testing.B) {
+ benchmarkIPEqual(b, IPv4len)
+ })
+ b.Run("IPv6", func(b *testing.B) {
+ benchmarkIPEqual(b, IPv6len)
+ })
+}
+
+func benchmarkIPEqual(b *testing.B, size int) {
+ ips := make([]IP, 1000)
+ for i := range ips {
+ ips[i] = make(IP, size)
+ rand.Read(ips[i])
+ }
+ // Half of the N are equal.
+ for i := 0; i < b.N/2; i++ {
+ x := ips[i%len(ips)]
+ y := ips[i%len(ips)]
+ x.Equal(y)
+ }
+ // The other half are not equal.
+ for i := 0; i < b.N/2; i++ {
+ x := ips[i%len(ips)]
+ y := ips[(i+1)%len(ips)]
+ x.Equal(y)
+ }
+}
diff --git a/go/src/net/iprawsock.go b/go/src/net/iprawsock.go
new file mode 100644
index 0000000000000000000000000000000000000000..26134d7e76a2ecbaed85aa692d7d1de458ad193f
--- /dev/null
+++ b/go/src/net/iprawsock.go
@@ -0,0 +1,258 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "context"
+ "net/netip"
+ "syscall"
+)
+
+// BUG(mikio): On every POSIX platform, reads from the "ip4" network
+// using the ReadFrom or ReadFromIP method might not return a complete
+// IPv4 packet, including its header, even if there is space
+// available. This can occur even in cases where Read or ReadMsgIP
+// could return a complete packet. For this reason, it is recommended
+// that you do not use these methods if it is important to receive a
+// full packet.
+//
+// The Go 1 compatibility guidelines make it impossible for us to
+// change the behavior of these methods; use Read or ReadMsgIP
+// instead.
+
+// BUG(mikio): On JS and Plan 9, methods and functions related
+// to IPConn are not implemented.
+
+// BUG: On Windows, raw IP sockets are restricted by the operating system.
+// Sending TCP data, sending UDP data with invalid source addresses,
+// and calling bind with TCP protocol don't work.
+//
+// See Winsock reference for details.
+
+func ipAddrFromAddr(addr netip.Addr) *IPAddr {
+ return &IPAddr{
+ IP: addr.AsSlice(),
+ Zone: addr.Zone(),
+ }
+}
+
+// IPAddr represents the address of an IP end point.
+type IPAddr struct {
+ IP IP
+ Zone string // IPv6 scoped addressing zone
+}
+
+// Network returns the address's network name, "ip".
+func (a *IPAddr) Network() string { return "ip" }
+
+func (a *IPAddr) String() string {
+ if a == nil {
+ return ""
+ }
+ ip := ipEmptyString(a.IP)
+ if a.Zone != "" {
+ return ip + "%" + a.Zone
+ }
+ return ip
+}
+
+func (a *IPAddr) isWildcard() bool {
+ if a == nil || a.IP == nil {
+ return true
+ }
+ return a.IP.IsUnspecified()
+}
+
+func (a *IPAddr) opAddr() Addr {
+ if a == nil {
+ return nil
+ }
+ return a
+}
+
+// ResolveIPAddr returns an address of IP end point.
+//
+// The network must be an IP network name.
+//
+// If the host in the address parameter is not a literal IP address,
+// ResolveIPAddr resolves the address to an address of IP end point.
+// Otherwise, it parses the address as a literal IP address.
+// The address parameter can use a host name, but this is not
+// recommended, because it will return at most one of the host name's
+// IP addresses.
+//
+// See func [Dial] for a description of the network and address
+// parameters.
+func ResolveIPAddr(network, address string) (*IPAddr, error) {
+ if network == "" { // a hint wildcard for Go 1.0 undocumented behavior
+ network = "ip"
+ }
+ afnet, _, err := parseNetwork(context.Background(), network, false)
+ if err != nil {
+ return nil, err
+ }
+ switch afnet {
+ case "ip", "ip4", "ip6":
+ default:
+ return nil, UnknownNetworkError(network)
+ }
+ addrs, err := DefaultResolver.internetAddrList(context.Background(), afnet, address)
+ if err != nil {
+ return nil, err
+ }
+ return addrs.forResolve(network, address).(*IPAddr), nil
+}
+
+// IPConn is the implementation of the [Conn] and [PacketConn] interfaces
+// for IP network connections.
+type IPConn struct {
+ conn
+}
+
+// SyscallConn returns a raw network connection.
+// This implements the [syscall.Conn] interface.
+func (c *IPConn) SyscallConn() (syscall.RawConn, error) {
+ if !c.ok() {
+ return nil, syscall.EINVAL
+ }
+ return newRawConn(c.fd), nil
+}
+
+// ReadFromIP acts like ReadFrom but returns an IPAddr.
+func (c *IPConn) ReadFromIP(b []byte) (int, *IPAddr, error) {
+ if !c.ok() {
+ return 0, nil, syscall.EINVAL
+ }
+ n, addr, err := c.readFrom(b)
+ if err != nil {
+ err = &OpError{Op: "read", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+ }
+ return n, addr, err
+}
+
+// ReadFrom implements the [PacketConn] ReadFrom method.
+func (c *IPConn) ReadFrom(b []byte) (int, Addr, error) {
+ if !c.ok() {
+ return 0, nil, syscall.EINVAL
+ }
+ n, addr, err := c.readFrom(b)
+ if err != nil {
+ err = &OpError{Op: "read", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+ }
+ if addr == nil {
+ return n, nil, err
+ }
+ return n, addr, err
+}
+
+// ReadMsgIP reads a message from c, copying the payload into b and
+// the associated out-of-band data into oob. It returns the number of
+// bytes copied into b, the number of bytes copied into oob, the flags
+// that were set on the message and the source address of the message.
+//
+// The packages golang.org/x/net/ipv4 and golang.org/x/net/ipv6 can be
+// used to manipulate IP-level socket options in oob.
+func (c *IPConn) ReadMsgIP(b, oob []byte) (n, oobn, flags int, addr *IPAddr, err error) {
+ if !c.ok() {
+ return 0, 0, 0, nil, syscall.EINVAL
+ }
+ n, oobn, flags, addr, err = c.readMsg(b, oob)
+ if err != nil {
+ err = &OpError{Op: "read", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+ }
+ return
+}
+
+// WriteToIP acts like [IPConn.WriteTo] but takes an [IPAddr].
+func (c *IPConn) WriteToIP(b []byte, addr *IPAddr) (int, error) {
+ if !c.ok() {
+ return 0, syscall.EINVAL
+ }
+ n, err := c.writeTo(b, addr)
+ if err != nil {
+ err = &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: addr.opAddr(), Err: err}
+ }
+ return n, err
+}
+
+// WriteTo implements the [PacketConn] WriteTo method.
+func (c *IPConn) WriteTo(b []byte, addr Addr) (int, error) {
+ if !c.ok() {
+ return 0, syscall.EINVAL
+ }
+ a, ok := addr.(*IPAddr)
+ if !ok {
+ return 0, &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: addr, Err: syscall.EINVAL}
+ }
+ n, err := c.writeTo(b, a)
+ if err != nil {
+ err = &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: a.opAddr(), Err: err}
+ }
+ return n, err
+}
+
+// WriteMsgIP writes a message to addr via c, copying the payload from
+// b and the associated out-of-band data from oob. It returns the
+// number of payload and out-of-band bytes written.
+//
+// The packages golang.org/x/net/ipv4 and golang.org/x/net/ipv6 can be
+// used to manipulate IP-level socket options in oob.
+func (c *IPConn) WriteMsgIP(b, oob []byte, addr *IPAddr) (n, oobn int, err error) {
+ if !c.ok() {
+ return 0, 0, syscall.EINVAL
+ }
+ n, oobn, err = c.writeMsg(b, oob, addr)
+ if err != nil {
+ err = &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: addr.opAddr(), Err: err}
+ }
+ return
+}
+
+func newIPConn(fd *netFD) *IPConn { return &IPConn{conn{fd}} }
+
+// DialIP acts like [Dial] for IP networks.
+//
+// The network must be an IP network name; see func Dial for details.
+//
+// If laddr is nil, a local address is automatically chosen.
+// If the IP field of raddr is nil or an unspecified IP address, the
+// local system is assumed.
+func DialIP(network string, laddr, raddr *IPAddr) (*IPConn, error) {
+ return dialIP(context.Background(), nil, network, laddr, raddr)
+}
+
+func dialIP(ctx context.Context, dialer *Dialer, network string, laddr, raddr *IPAddr) (*IPConn, error) {
+ if raddr == nil {
+ return nil, &OpError{Op: "dial", Net: network, Source: laddr.opAddr(), Addr: nil, Err: errMissingAddress}
+ }
+ sd := &sysDialer{network: network, address: raddr.String()}
+ if dialer != nil {
+ sd.Dialer = *dialer
+ }
+ c, err := sd.dialIP(ctx, laddr, raddr)
+ if err != nil {
+ return nil, &OpError{Op: "dial", Net: network, Source: laddr.opAddr(), Addr: raddr.opAddr(), Err: err}
+ }
+ return c, nil
+}
+
+// ListenIP acts like [ListenPacket] for IP networks.
+//
+// The network must be an IP network name; see func Dial for details.
+//
+// If the IP field of laddr is nil or an unspecified IP address,
+// ListenIP listens on all available IP addresses of the local system
+// except multicast IP addresses.
+func ListenIP(network string, laddr *IPAddr) (*IPConn, error) {
+ if laddr == nil {
+ laddr = &IPAddr{}
+ }
+ sl := &sysListener{network: network, address: laddr.String()}
+ c, err := sl.listenIP(context.Background(), laddr)
+ if err != nil {
+ return nil, &OpError{Op: "listen", Net: network, Source: nil, Addr: laddr.opAddr(), Err: err}
+ }
+ return c, nil
+}
diff --git a/go/src/net/iprawsock_plan9.go b/go/src/net/iprawsock_plan9.go
new file mode 100644
index 0000000000000000000000000000000000000000..ebe58088642de4b2f0bfaccb0f478af95cda44bd
--- /dev/null
+++ b/go/src/net/iprawsock_plan9.go
@@ -0,0 +1,34 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "context"
+ "syscall"
+)
+
+func (c *IPConn) readFrom(b []byte) (int, *IPAddr, error) {
+ return 0, nil, syscall.EPLAN9
+}
+
+func (c *IPConn) readMsg(b, oob []byte) (n, oobn, flags int, addr *IPAddr, err error) {
+ return 0, 0, 0, nil, syscall.EPLAN9
+}
+
+func (c *IPConn) writeTo(b []byte, addr *IPAddr) (int, error) {
+ return 0, syscall.EPLAN9
+}
+
+func (c *IPConn) writeMsg(b, oob []byte, addr *IPAddr) (n, oobn int, err error) {
+ return 0, 0, syscall.EPLAN9
+}
+
+func (sd *sysDialer) dialIP(ctx context.Context, laddr, raddr *IPAddr) (*IPConn, error) {
+ return nil, syscall.EPLAN9
+}
+
+func (sl *sysListener) listenIP(ctx context.Context, laddr *IPAddr) (*IPConn, error) {
+ return nil, syscall.EPLAN9
+}
diff --git a/go/src/net/iprawsock_posix.go b/go/src/net/iprawsock_posix.go
new file mode 100644
index 0000000000000000000000000000000000000000..b25cb648c3dc0d1bf51e9692b887ff651519db38
--- /dev/null
+++ b/go/src/net/iprawsock_posix.go
@@ -0,0 +1,159 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || js || wasip1 || windows
+
+package net
+
+import (
+ "context"
+ "syscall"
+)
+
+func sockaddrToIP(sa syscall.Sockaddr) Addr {
+ switch sa := sa.(type) {
+ case *syscall.SockaddrInet4:
+ return &IPAddr{IP: sa.Addr[0:]}
+ case *syscall.SockaddrInet6:
+ return &IPAddr{IP: sa.Addr[0:], Zone: zoneCache.name(int(sa.ZoneId))}
+ }
+ return nil
+}
+
+func (a *IPAddr) family() int {
+ if a == nil || len(a.IP) <= IPv4len {
+ return syscall.AF_INET
+ }
+ if a.IP.To4() != nil {
+ return syscall.AF_INET
+ }
+ return syscall.AF_INET6
+}
+
+func (a *IPAddr) sockaddr(family int) (syscall.Sockaddr, error) {
+ if a == nil {
+ return nil, nil
+ }
+ return ipToSockaddr(family, a.IP, 0, a.Zone)
+}
+
+func (a *IPAddr) toLocal(net string) sockaddr {
+ return &IPAddr{loopbackIP(net), a.Zone}
+}
+
+func (c *IPConn) readFrom(b []byte) (int, *IPAddr, error) {
+ // TODO(cw,rsc): consider using readv if we know the family
+ // type to avoid the header trim/copy
+ var addr *IPAddr
+ n, sa, err := c.fd.readFrom(b)
+ switch sa := sa.(type) {
+ case *syscall.SockaddrInet4:
+ addr = &IPAddr{IP: sa.Addr[0:]}
+ n = stripIPv4Header(n, b)
+ case *syscall.SockaddrInet6:
+ addr = &IPAddr{IP: sa.Addr[0:], Zone: zoneCache.name(int(sa.ZoneId))}
+ }
+ return n, addr, err
+}
+
+func stripIPv4Header(n int, b []byte) int {
+ if len(b) < 20 {
+ return n
+ }
+ l := int(b[0]&0x0f) << 2
+ if 20 > l || l > len(b) {
+ return n
+ }
+ if b[0]>>4 != 4 {
+ return n
+ }
+ copy(b, b[l:])
+ return n - l
+}
+
+func (c *IPConn) readMsg(b, oob []byte) (n, oobn, flags int, addr *IPAddr, err error) {
+ var sa syscall.Sockaddr
+ n, oobn, flags, sa, err = c.fd.readMsg(b, oob, 0)
+ switch sa := sa.(type) {
+ case *syscall.SockaddrInet4:
+ addr = &IPAddr{IP: sa.Addr[0:]}
+ case *syscall.SockaddrInet6:
+ addr = &IPAddr{IP: sa.Addr[0:], Zone: zoneCache.name(int(sa.ZoneId))}
+ }
+ return
+}
+
+func (c *IPConn) writeTo(b []byte, addr *IPAddr) (int, error) {
+ if c.fd.isConnected {
+ return 0, ErrWriteToConnected
+ }
+ if addr == nil {
+ return 0, errMissingAddress
+ }
+ sa, err := addr.sockaddr(c.fd.family)
+ if err != nil {
+ return 0, err
+ }
+ return c.fd.writeTo(b, sa)
+}
+
+func (c *IPConn) writeMsg(b, oob []byte, addr *IPAddr) (n, oobn int, err error) {
+ if c.fd.isConnected {
+ return 0, 0, ErrWriteToConnected
+ }
+ if addr == nil {
+ return 0, 0, errMissingAddress
+ }
+ sa, err := addr.sockaddr(c.fd.family)
+ if err != nil {
+ return 0, 0, err
+ }
+ return c.fd.writeMsg(b, oob, sa)
+}
+
+func (sd *sysDialer) dialIP(ctx context.Context, laddr, raddr *IPAddr) (*IPConn, error) {
+ network, proto, err := parseNetwork(ctx, sd.network, true)
+ if err != nil {
+ return nil, err
+ }
+ switch network {
+ case "ip", "ip4", "ip6":
+ default:
+ return nil, UnknownNetworkError(sd.network)
+ }
+ ctrlCtxFn := sd.Dialer.ControlContext
+ if ctrlCtxFn == nil && sd.Dialer.Control != nil {
+ ctrlCtxFn = func(ctx context.Context, network, address string, c syscall.RawConn) error {
+ return sd.Dialer.Control(network, address, c)
+ }
+ }
+ fd, err := internetSocket(ctx, network, laddr, raddr, syscall.SOCK_RAW, proto, "dial", ctrlCtxFn)
+ if err != nil {
+ return nil, err
+ }
+ return newIPConn(fd), nil
+}
+
+func (sl *sysListener) listenIP(ctx context.Context, laddr *IPAddr) (*IPConn, error) {
+ network, proto, err := parseNetwork(ctx, sl.network, true)
+ if err != nil {
+ return nil, err
+ }
+ switch network {
+ case "ip", "ip4", "ip6":
+ default:
+ return nil, UnknownNetworkError(sl.network)
+ }
+ var ctrlCtxFn func(ctx context.Context, network, address string, c syscall.RawConn) error
+ if sl.ListenConfig.Control != nil {
+ ctrlCtxFn = func(ctx context.Context, network, address string, c syscall.RawConn) error {
+ return sl.ListenConfig.Control(network, address, c)
+ }
+ }
+ fd, err := internetSocket(ctx, network, laddr, nil, syscall.SOCK_RAW, proto, "listen", ctrlCtxFn)
+ if err != nil {
+ return nil, err
+ }
+ return newIPConn(fd), nil
+}
diff --git a/go/src/net/iprawsock_test.go b/go/src/net/iprawsock_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..7f1fc139abc82c4589213eb3a0beb70eb44d58d4
--- /dev/null
+++ b/go/src/net/iprawsock_test.go
@@ -0,0 +1,200 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "internal/testenv"
+ "reflect"
+ "testing"
+)
+
+// The full stack test cases for IPConn have been moved to the
+// following:
+// golang.org/x/net/ipv4
+// golang.org/x/net/ipv6
+// golang.org/x/net/icmp
+
+type resolveIPAddrTest struct {
+ network string
+ litAddrOrName string
+ addr *IPAddr
+ err error
+}
+
+var resolveIPAddrTests = []resolveIPAddrTest{
+ {"ip", "127.0.0.1", &IPAddr{IP: IPv4(127, 0, 0, 1)}, nil},
+ {"ip4", "127.0.0.1", &IPAddr{IP: IPv4(127, 0, 0, 1)}, nil},
+ {"ip4:icmp", "127.0.0.1", &IPAddr{IP: IPv4(127, 0, 0, 1)}, nil},
+
+ {"ip", "::1", &IPAddr{IP: ParseIP("::1")}, nil},
+ {"ip6", "::1", &IPAddr{IP: ParseIP("::1")}, nil},
+ {"ip6:ipv6-icmp", "::1", &IPAddr{IP: ParseIP("::1")}, nil},
+ {"ip6:IPv6-ICMP", "::1", &IPAddr{IP: ParseIP("::1")}, nil},
+
+ {"ip", "::1%en0", &IPAddr{IP: ParseIP("::1"), Zone: "en0"}, nil},
+ {"ip6", "::1%911", &IPAddr{IP: ParseIP("::1"), Zone: "911"}, nil},
+
+ {"", "127.0.0.1", &IPAddr{IP: IPv4(127, 0, 0, 1)}, nil}, // Go 1.0 behavior
+ {"", "::1", &IPAddr{IP: ParseIP("::1")}, nil}, // Go 1.0 behavior
+
+ {"ip4:icmp", "", &IPAddr{}, nil},
+
+ {"l2tp", "127.0.0.1", nil, UnknownNetworkError("l2tp")},
+ {"l2tp:gre", "127.0.0.1", nil, UnknownNetworkError("l2tp:gre")},
+ {"tcp", "1.2.3.4:123", nil, UnknownNetworkError("tcp")},
+
+ {"ip4", "2001:db8::1", nil, &AddrError{Err: errNoSuitableAddress.Error(), Addr: "2001:db8::1"}},
+ {"ip4:icmp", "2001:db8::1", nil, &AddrError{Err: errNoSuitableAddress.Error(), Addr: "2001:db8::1"}},
+ {"ip6", "127.0.0.1", nil, &AddrError{Err: errNoSuitableAddress.Error(), Addr: "127.0.0.1"}},
+ {"ip6", "::ffff:127.0.0.1", nil, &AddrError{Err: errNoSuitableAddress.Error(), Addr: "::ffff:127.0.0.1"}},
+ {"ip6:ipv6-icmp", "127.0.0.1", nil, &AddrError{Err: errNoSuitableAddress.Error(), Addr: "127.0.0.1"}},
+ {"ip6:ipv6-icmp", "::ffff:127.0.0.1", nil, &AddrError{Err: errNoSuitableAddress.Error(), Addr: "::ffff:127.0.0.1"}},
+}
+
+func TestResolveIPAddr(t *testing.T) {
+ if !testableNetwork("ip+nopriv") {
+ t.Skip("ip+nopriv test")
+ }
+
+ origTestHookLookupIP := testHookLookupIP
+ defer func() { testHookLookupIP = origTestHookLookupIP }()
+ testHookLookupIP = lookupLocalhost
+
+ for _, tt := range resolveIPAddrTests {
+ addr, err := ResolveIPAddr(tt.network, tt.litAddrOrName)
+ if !reflect.DeepEqual(addr, tt.addr) || !reflect.DeepEqual(err, tt.err) {
+ t.Errorf("ResolveIPAddr(%q, %q) = %#v, %v, want %#v, %v", tt.network, tt.litAddrOrName, addr, err, tt.addr, tt.err)
+ continue
+ }
+ if err == nil {
+ addr2, err := ResolveIPAddr(addr.Network(), addr.String())
+ if !reflect.DeepEqual(addr2, tt.addr) || err != tt.err {
+ t.Errorf("(%q, %q): ResolveIPAddr(%q, %q) = %#v, %v, want %#v, %v", tt.network, tt.litAddrOrName, addr.Network(), addr.String(), addr2, err, tt.addr, tt.err)
+ }
+ }
+ }
+}
+
+var ipConnLocalNameTests = []struct {
+ net string
+ laddr *IPAddr
+}{
+ {"ip4:icmp", &IPAddr{IP: IPv4(127, 0, 0, 1)}},
+ {"ip4:icmp", &IPAddr{}},
+ {"ip4:icmp", nil},
+}
+
+func TestIPConnLocalName(t *testing.T) {
+ for _, tt := range ipConnLocalNameTests {
+ if !testableNetwork(tt.net) {
+ t.Logf("skipping %s test", tt.net)
+ continue
+ }
+ c, err := ListenIP(tt.net, tt.laddr)
+ if testenv.SyscallIsNotSupported(err) {
+ // May be inside a container that disallows creating a socket.
+ t.Logf("skipping %s test: %v", tt.net, err)
+ continue
+ } else if err != nil {
+ t.Fatal(err)
+ }
+ defer c.Close()
+ if la := c.LocalAddr(); la == nil {
+ t.Fatal("should not fail")
+ }
+ }
+}
+
+func TestIPConnRemoteName(t *testing.T) {
+ network := "ip:tcp"
+ if !testableNetwork(network) {
+ t.Skipf("skipping %s test", network)
+ }
+
+ raddr := &IPAddr{IP: IPv4(127, 0, 0, 1).To4()}
+ c, err := DialIP(network, &IPAddr{IP: IPv4(127, 0, 0, 1)}, raddr)
+ if testenv.SyscallIsNotSupported(err) {
+ // May be inside a container that disallows creating a socket.
+ t.Skipf("skipping %s test: %v", network, err)
+ } else if err != nil {
+ t.Fatal(err)
+ }
+ defer c.Close()
+ if !reflect.DeepEqual(raddr, c.RemoteAddr()) {
+ t.Fatalf("got %#v; want %#v", c.RemoteAddr(), raddr)
+ }
+}
+
+func TestDialListenIPArgs(t *testing.T) {
+ type test struct {
+ argLists [][2]string
+ shouldFail bool
+ }
+ tests := []test{
+ {
+ argLists: [][2]string{
+ {"ip", "127.0.0.1"},
+ {"ip:", "127.0.0.1"},
+ {"ip::", "127.0.0.1"},
+ {"ip", "::1"},
+ {"ip:", "::1"},
+ {"ip::", "::1"},
+ {"ip4", "127.0.0.1"},
+ {"ip4:", "127.0.0.1"},
+ {"ip4::", "127.0.0.1"},
+ {"ip6", "::1"},
+ {"ip6:", "::1"},
+ {"ip6::", "::1"},
+ },
+ shouldFail: true,
+ },
+ }
+ if testableNetwork("ip") {
+ priv := test{shouldFail: false}
+ for _, tt := range []struct {
+ network, address string
+ args [2]string
+ }{
+ {"ip4:47", "127.0.0.1", [2]string{"ip4:47", "127.0.0.1"}},
+ {"ip6:47", "::1", [2]string{"ip6:47", "::1"}},
+ } {
+ c, err := ListenPacket(tt.network, tt.address)
+ if err != nil {
+ continue
+ }
+ c.Close()
+ priv.argLists = append(priv.argLists, tt.args)
+ }
+ if len(priv.argLists) > 0 {
+ tests = append(tests, priv)
+ }
+ }
+
+ for _, tt := range tests {
+ for _, args := range tt.argLists {
+ _, err := Dial(args[0], args[1])
+ if tt.shouldFail != (err != nil) {
+ t.Errorf("Dial(%q, %q) = %v; want (err != nil) is %t", args[0], args[1], err, tt.shouldFail)
+ }
+ _, err = ListenPacket(args[0], args[1])
+ if tt.shouldFail != (err != nil) {
+ t.Errorf("ListenPacket(%q, %q) = %v; want (err != nil) is %t", args[0], args[1], err, tt.shouldFail)
+ }
+ a, err := ResolveIPAddr("ip", args[1])
+ if err != nil {
+ t.Errorf("ResolveIPAddr(\"ip\", %q) = %v", args[1], err)
+ continue
+ }
+ _, err = DialIP(args[0], nil, a)
+ if tt.shouldFail != (err != nil) {
+ t.Errorf("DialIP(%q, %v) = %v; want (err != nil) is %t", args[0], a, err, tt.shouldFail)
+ }
+ _, err = ListenIP(args[0], a)
+ if tt.shouldFail != (err != nil) {
+ t.Errorf("ListenIP(%q, %v) = %v; want (err != nil) is %t", args[0], a, err, tt.shouldFail)
+ }
+ }
+ }
+}
diff --git a/go/src/net/ipsock.go b/go/src/net/ipsock.go
new file mode 100644
index 0000000000000000000000000000000000000000..496faf346ec1e0e33ba5c3779d4455d5d94bd154
--- /dev/null
+++ b/go/src/net/ipsock.go
@@ -0,0 +1,327 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "context"
+ "internal/bytealg"
+ "runtime"
+ "sync"
+ _ "unsafe" // for linkname
+)
+
+// BUG(rsc,mikio): On DragonFly BSD and OpenBSD, listening on the
+// "tcp" and "udp" networks does not listen for both IPv4 and IPv6
+// connections. This is due to the fact that IPv4 traffic will not be
+// routed to an IPv6 socket - two separate sockets are required if
+// both address families are to be supported.
+// See inet6(4) for details.
+
+type ipStackCapabilities struct {
+ sync.Once // guards following
+ ipv4Enabled bool
+ ipv6Enabled bool
+ ipv4MappedIPv6Enabled bool
+}
+
+var ipStackCaps ipStackCapabilities
+
+// supportsIPv4 reports whether the platform supports IPv4 networking
+// functionality.
+func supportsIPv4() bool {
+ ipStackCaps.Once.Do(ipStackCaps.probe)
+ return ipStackCaps.ipv4Enabled
+}
+
+// supportsIPv6 reports whether the platform supports IPv6 networking
+// functionality.
+func supportsIPv6() bool {
+ ipStackCaps.Once.Do(ipStackCaps.probe)
+ return ipStackCaps.ipv6Enabled
+}
+
+// supportsIPv4map reports whether the platform supports mapping an
+// IPv4 address inside an IPv6 address at transport layer
+// protocols. See RFC 4291, RFC 4038 and RFC 3493.
+func supportsIPv4map() bool {
+ // Some operating systems provide no support for mapping IPv4
+ // addresses to IPv6, and a runtime check is unnecessary.
+ switch runtime.GOOS {
+ case "dragonfly", "openbsd":
+ return false
+ }
+
+ ipStackCaps.Once.Do(ipStackCaps.probe)
+ return ipStackCaps.ipv4MappedIPv6Enabled
+}
+
+// An addrList represents a list of network endpoint addresses.
+type addrList []Addr
+
+// isIPv4 reports whether addr contains an IPv4 address.
+func isIPv4(addr Addr) bool {
+ switch addr := addr.(type) {
+ case *TCPAddr:
+ return addr.IP.To4() != nil
+ case *UDPAddr:
+ return addr.IP.To4() != nil
+ case *IPAddr:
+ return addr.IP.To4() != nil
+ }
+ return false
+}
+
+// isNotIPv4 reports whether addr does not contain an IPv4 address.
+func isNotIPv4(addr Addr) bool { return !isIPv4(addr) }
+
+// forResolve returns the most appropriate address in address for
+// a call to ResolveTCPAddr, ResolveUDPAddr, or ResolveIPAddr.
+// IPv4 is preferred, unless addr contains an IPv6 literal.
+func (addrs addrList) forResolve(network, addr string) Addr {
+ var want6 bool
+ switch network {
+ case "ip":
+ // IPv6 literal (addr does NOT contain a port)
+ want6 = bytealg.CountString(addr, ':') > 0
+ case "tcp", "udp":
+ // IPv6 literal. (addr contains a port, so look for '[')
+ want6 = bytealg.CountString(addr, '[') > 0
+ }
+ if want6 {
+ return addrs.first(isNotIPv4)
+ }
+ return addrs.first(isIPv4)
+}
+
+// first returns the first address which satisfies strategy, or if
+// none do, then the first address of any kind.
+func (addrs addrList) first(strategy func(Addr) bool) Addr {
+ for _, addr := range addrs {
+ if strategy(addr) {
+ return addr
+ }
+ }
+ return addrs[0]
+}
+
+// partition divides an address list into two categories, using a
+// strategy function to assign a boolean label to each address.
+// The first address, and any with a matching label, are returned as
+// primaries, while addresses with the opposite label are returned
+// as fallbacks. For non-empty inputs, primaries is guaranteed to be
+// non-empty.
+func (addrs addrList) partition(strategy func(Addr) bool) (primaries, fallbacks addrList) {
+ var primaryLabel bool
+ for i, addr := range addrs {
+ label := strategy(addr)
+ if i == 0 || label == primaryLabel {
+ primaryLabel = label
+ primaries = append(primaries, addr)
+ } else {
+ fallbacks = append(fallbacks, addr)
+ }
+ }
+ return
+}
+
+// filterAddrList applies a filter to a list of IP addresses,
+// yielding a list of Addr objects. Known filters are nil, ipv4only,
+// and ipv6only. It returns every address when the filter is nil.
+// The result contains at least one address when error is nil.
+func filterAddrList(filter func(IPAddr) bool, ips []IPAddr, inetaddr func(IPAddr) Addr, originalAddr string) (addrList, error) {
+ var addrs addrList
+ for _, ip := range ips {
+ if filter == nil || filter(ip) {
+ addrs = append(addrs, inetaddr(ip))
+ }
+ }
+ if len(addrs) == 0 {
+ return nil, &AddrError{Err: errNoSuitableAddress.Error(), Addr: originalAddr}
+ }
+ return addrs, nil
+}
+
+// ipv4only reports whether addr is an IPv4 address.
+func ipv4only(addr IPAddr) bool {
+ return addr.IP.To4() != nil
+}
+
+// ipv6only reports whether addr is an IPv6 address except IPv4-mapped IPv6 address.
+func ipv6only(addr IPAddr) bool {
+ return len(addr.IP) == IPv6len && addr.IP.To4() == nil
+}
+
+// SplitHostPort splits a network address of the form "host:port",
+// "host%zone:port", "[host]:port" or "[host%zone]:port" into host or
+// host%zone and port.
+//
+// A literal IPv6 address in hostport must be enclosed in square
+// brackets, as in "[::1]:80", "[::1%lo0]:80".
+//
+// See func Dial for a description of the hostport parameter, and host
+// and port results.
+func SplitHostPort(hostport string) (host, port string, err error) {
+ const (
+ missingPort = "missing port in address"
+ tooManyColons = "too many colons in address"
+ )
+ addrErr := func(addr, why string) (host, port string, err error) {
+ return "", "", &AddrError{Err: why, Addr: addr}
+ }
+ j, k := 0, 0
+
+ // The port starts after the last colon.
+ i := bytealg.LastIndexByteString(hostport, ':')
+ if i < 0 {
+ return addrErr(hostport, missingPort)
+ }
+
+ if hostport[0] == '[' {
+ // Expect the first ']' just before the last ':'.
+ end := bytealg.IndexByteString(hostport, ']')
+ if end < 0 {
+ return addrErr(hostport, "missing ']' in address")
+ }
+ switch end + 1 {
+ case len(hostport):
+ // There can't be a ':' behind the ']' now.
+ return addrErr(hostport, missingPort)
+ case i:
+ // The expected result.
+ default:
+ // Either ']' isn't followed by a colon, or it is
+ // followed by a colon that is not the last one.
+ if hostport[end+1] == ':' {
+ return addrErr(hostport, tooManyColons)
+ }
+ return addrErr(hostport, missingPort)
+ }
+ host = hostport[1:end]
+ j, k = 1, end+1 // there can't be a '[' resp. ']' before these positions
+ } else {
+ host = hostport[:i]
+ if bytealg.IndexByteString(host, ':') >= 0 {
+ return addrErr(hostport, tooManyColons)
+ }
+ }
+ if bytealg.IndexByteString(hostport[j:], '[') >= 0 {
+ return addrErr(hostport, "unexpected '[' in address")
+ }
+ if bytealg.IndexByteString(hostport[k:], ']') >= 0 {
+ return addrErr(hostport, "unexpected ']' in address")
+ }
+
+ port = hostport[i+1:]
+ return host, port, nil
+}
+
+func splitHostZone(s string) (host, zone string) {
+ // The IPv6 scoped addressing zone identifier starts after the
+ // last percent sign.
+ if i := bytealg.LastIndexByteString(s, '%'); i > 0 {
+ host, zone = s[:i], s[i+1:]
+ } else {
+ host = s
+ }
+ return
+}
+
+// JoinHostPort combines host and port into a network address of the
+// form "host:port". If host contains a colon, as found in literal
+// IPv6 addresses, then JoinHostPort returns "[host]:port".
+//
+// See func Dial for a description of the host and port parameters.
+func JoinHostPort(host, port string) string {
+ // We assume that host is a literal IPv6 address if host has
+ // colons.
+ if bytealg.IndexByteString(host, ':') >= 0 {
+ return "[" + host + "]:" + port
+ }
+ return host + ":" + port
+}
+
+// internetAddrList resolves addr, which may be a literal IP
+// address or a DNS name, and returns a list of internet protocol
+// family addresses. The result contains at least one address when
+// error is nil.
+func (r *Resolver) internetAddrList(ctx context.Context, net, addr string) (addrList, error) {
+ var (
+ err error
+ host, port string
+ portnum int
+ )
+ switch net {
+ case "tcp", "tcp4", "tcp6", "udp", "udp4", "udp6":
+ if addr != "" {
+ if host, port, err = SplitHostPort(addr); err != nil {
+ return nil, err
+ }
+ if portnum, err = r.LookupPort(ctx, net, port); err != nil {
+ return nil, err
+ }
+ }
+ case "ip", "ip4", "ip6":
+ if addr != "" {
+ host = addr
+ }
+ default:
+ return nil, UnknownNetworkError(net)
+ }
+ inetaddr := func(ip IPAddr) Addr {
+ switch net {
+ case "tcp", "tcp4", "tcp6":
+ return &TCPAddr{IP: ip.IP, Port: portnum, Zone: ip.Zone}
+ case "udp", "udp4", "udp6":
+ return &UDPAddr{IP: ip.IP, Port: portnum, Zone: ip.Zone}
+ case "ip", "ip4", "ip6":
+ return &IPAddr{IP: ip.IP, Zone: ip.Zone}
+ default:
+ panic("unexpected network: " + net)
+ }
+ }
+ if host == "" {
+ return addrList{inetaddr(IPAddr{})}, nil
+ }
+
+ // Try as a literal IP address, then as a DNS name.
+ ips, err := r.lookupIPAddr(ctx, net, host)
+ if err != nil {
+ return nil, err
+ }
+ // Issue 18806: if the machine has halfway configured
+ // IPv6 such that it can bind on "::" (IPv6unspecified)
+ // but not connect back to that same address, fall
+ // back to dialing 0.0.0.0.
+ if len(ips) == 1 && ips[0].IP.Equal(IPv6unspecified) {
+ ips = append(ips, IPAddr{IP: IPv4zero})
+ }
+
+ var filter func(IPAddr) bool
+ if net != "" && net[len(net)-1] == '4' {
+ filter = ipv4only
+ }
+ if net != "" && net[len(net)-1] == '6' {
+ filter = ipv6only
+ }
+ return filterAddrList(filter, ips, inetaddr, host)
+}
+
+// loopbackIP should be an internal detail,
+// but widely used packages access it using linkname.
+// Notable members of the hall of shame include:
+// - github.com/database64128/tfo-go/v2
+// - github.com/metacubex/tfo-go
+// - github.com/sagernet/tfo-go
+//
+// Do not remove or change the type signature.
+// See go.dev/issue/67401.
+//
+//go:linkname loopbackIP
+func loopbackIP(net string) IP {
+ if net != "" && net[len(net)-1] == '6' {
+ return IPv6loopback
+ }
+ return IP{127, 0, 0, 1}
+}
diff --git a/go/src/net/ipsock_plan9.go b/go/src/net/ipsock_plan9.go
new file mode 100644
index 0000000000000000000000000000000000000000..2bd5071d56a598f61ba53d0348fd2a174135ddb4
--- /dev/null
+++ b/go/src/net/ipsock_plan9.go
@@ -0,0 +1,367 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "context"
+ "internal/bytealg"
+ "internal/strconv"
+ "io/fs"
+ "os"
+ "syscall"
+)
+
+// probe probes IPv4, IPv6 and IPv4-mapped IPv6 communication
+// capabilities.
+//
+// Plan 9 uses IPv6 natively, see ip(3).
+func (p *ipStackCapabilities) probe() {
+ p.ipv4Enabled = probe(netdir+"/iproute", "4i")
+ p.ipv6Enabled = probe(netdir+"/iproute", "6i")
+ if p.ipv4Enabled && p.ipv6Enabled {
+ p.ipv4MappedIPv6Enabled = true
+ }
+}
+
+func probe(filename, query string) bool {
+ var file *file
+ var err error
+ if file, err = open(filename); err != nil {
+ return false
+ }
+ defer file.close()
+
+ r := false
+ for line, ok := file.readLine(); ok && !r; line, ok = file.readLine() {
+ f := getFields(line)
+ if len(f) < 3 {
+ continue
+ }
+ for i := 0; i < len(f); i++ {
+ if query == f[i] {
+ r = true
+ break
+ }
+ }
+ }
+ return r
+}
+
+// parsePlan9Addr parses address of the form [ip!]port (e.g. 127.0.0.1!80).
+func parsePlan9Addr(s string) (ip IP, iport int, err error) {
+ addr := IPv4zero // address contains port only
+ i := bytealg.IndexByteString(s, '!')
+ if i >= 0 {
+ addr = ParseIP(s[:i])
+ if addr == nil {
+ return nil, 0, &ParseError{Type: "IP address", Text: s}
+ }
+ }
+ p, plen, ok := dtoi(s[i+1:])
+ if !ok {
+ return nil, 0, &ParseError{Type: "port", Text: s}
+ }
+ if p < 0 || p > 0xFFFF {
+ return nil, 0, &AddrError{Err: "invalid port", Addr: s[i+1 : i+1+plen]}
+ }
+ return addr, p, nil
+}
+
+func readPlan9Addr(net, filename string) (addr Addr, err error) {
+ var buf [128]byte
+
+ f, err := os.Open(filename)
+ if err != nil {
+ return
+ }
+ defer f.Close()
+ n, err := f.Read(buf[:])
+ if err != nil {
+ return
+ }
+ ip, port, err := parsePlan9Addr(string(buf[:n]))
+ if err != nil {
+ return
+ }
+ switch net {
+ case "tcp4", "udp4":
+ if ip.Equal(IPv6zero) {
+ ip = ip[:IPv4len]
+ }
+ }
+ switch net {
+ case "tcp", "tcp4", "tcp6":
+ addr = &TCPAddr{IP: ip, Port: port}
+ case "udp", "udp4", "udp6":
+ addr = &UDPAddr{IP: ip, Port: port}
+ default:
+ return nil, UnknownNetworkError(net)
+ }
+ return addr, nil
+}
+
+func startPlan9(ctx context.Context, net string, addr Addr) (ctl *os.File, dest, proto, name string, err error) {
+ var (
+ ip IP
+ port int
+ )
+ switch a := addr.(type) {
+ case *TCPAddr:
+ proto = "tcp"
+ ip = a.IP
+ port = a.Port
+ case *UDPAddr:
+ proto = "udp"
+ ip = a.IP
+ port = a.Port
+ default:
+ err = UnknownNetworkError(net)
+ return
+ }
+
+ if port > 65535 {
+ err = InvalidAddrError("port should be < 65536")
+ return
+ }
+
+ clone, dest, err := queryCS1(ctx, proto, ip, port)
+ if err != nil {
+ err = handlePlan9DNSError(err, net+":"+ip.String()+":"+strconv.Itoa(port))
+ return
+ }
+ f, err := os.OpenFile(clone, os.O_RDWR, 0)
+ if err != nil {
+ return
+ }
+ var buf [16]byte
+ n, err := f.Read(buf[:])
+ if err != nil {
+ f.Close()
+ return
+ }
+ return f, dest, proto, string(buf[:n]), nil
+}
+
+func fixErr(err error) {
+ oe, ok := err.(*OpError)
+ if !ok {
+ return
+ }
+ nonNilInterface := func(a Addr) bool {
+ switch a := a.(type) {
+ case *TCPAddr:
+ return a == nil
+ case *UDPAddr:
+ return a == nil
+ case *IPAddr:
+ return a == nil
+ default:
+ return false
+ }
+ }
+ if nonNilInterface(oe.Source) {
+ oe.Source = nil
+ }
+ if nonNilInterface(oe.Addr) {
+ oe.Addr = nil
+ }
+ if pe, ok := oe.Err.(*fs.PathError); ok {
+ if _, ok = pe.Err.(syscall.ErrorString); ok {
+ oe.Err = pe.Err
+ }
+ }
+}
+
+func dialPlan9(ctx context.Context, net string, laddr, raddr Addr) (fd *netFD, err error) {
+ defer func() { fixErr(err) }()
+ type res struct {
+ fd *netFD
+ err error
+ }
+ resc := make(chan res)
+ go func() {
+ fd, err := dialPlan9Blocking(ctx, net, laddr, raddr)
+ select {
+ case resc <- res{fd, err}:
+ case <-ctx.Done():
+ if fd != nil {
+ fd.Close()
+ }
+ }
+ }()
+ select {
+ case res := <-resc:
+ return res.fd, res.err
+ case <-ctx.Done():
+ return nil, mapErr(ctx.Err())
+ }
+}
+
+func dialPlan9Blocking(ctx context.Context, net string, laddr, raddr Addr) (fd *netFD, err error) {
+ if isWildcard(raddr) {
+ raddr = toLocal(raddr, net)
+ }
+ f, dest, proto, name, err := startPlan9(ctx, net, raddr)
+ if err != nil {
+ return nil, err
+ }
+ if la := plan9LocalAddr(laddr); la == "" {
+ err = hangupCtlWrite(ctx, proto, f, "connect "+dest)
+ } else {
+ err = hangupCtlWrite(ctx, proto, f, "connect "+dest+" "+la)
+ }
+ if err != nil {
+ f.Close()
+ return nil, err
+ }
+ data, err := os.OpenFile(netdir+"/"+proto+"/"+name+"/data", os.O_RDWR, 0)
+ if err != nil {
+ f.Close()
+ return nil, err
+ }
+ laddr, err = readPlan9Addr(net, netdir+"/"+proto+"/"+name+"/local")
+ if err != nil {
+ data.Close()
+ f.Close()
+ return nil, err
+ }
+ return newFD(proto, name, nil, f, data, laddr, raddr)
+}
+
+func listenPlan9(ctx context.Context, net string, laddr Addr) (fd *netFD, err error) {
+ defer func() { fixErr(err) }()
+ f, dest, proto, name, err := startPlan9(ctx, net, laddr)
+ if err != nil {
+ return nil, err
+ }
+ _, err = f.WriteString("announce " + dest)
+ if err != nil {
+ f.Close()
+ return nil, &OpError{Op: "announce", Net: net, Source: laddr, Addr: nil, Err: err}
+ }
+ laddr, err = readPlan9Addr(net, netdir+"/"+proto+"/"+name+"/local")
+ if err != nil {
+ f.Close()
+ return nil, err
+ }
+ return newFD(proto, name, nil, f, nil, laddr, nil)
+}
+
+func (fd *netFD) netFD() (*netFD, error) {
+ return newFD(fd.net, fd.n, fd.listen, fd.ctl, fd.data, fd.laddr, fd.raddr)
+}
+
+func (fd *netFD) acceptPlan9() (nfd *netFD, err error) {
+ defer func() { fixErr(err) }()
+ if err := fd.pfd.ReadLock(); err != nil {
+ return nil, err
+ }
+ defer fd.pfd.ReadUnlock()
+ listen, err := os.Open(fd.dir + "/listen")
+ if err != nil {
+ return nil, err
+ }
+ var buf [16]byte
+ n, err := listen.Read(buf[:])
+ if err != nil {
+ listen.Close()
+ return nil, err
+ }
+ name := string(buf[:n])
+ ctl, err := os.OpenFile(netdir+"/"+fd.net+"/"+name+"/ctl", os.O_RDWR, 0)
+ if err != nil {
+ listen.Close()
+ return nil, err
+ }
+ data, err := os.OpenFile(netdir+"/"+fd.net+"/"+name+"/data", os.O_RDWR, 0)
+ if err != nil {
+ listen.Close()
+ ctl.Close()
+ return nil, err
+ }
+ raddr, err := readPlan9Addr(fd.net, netdir+"/"+fd.net+"/"+name+"/remote")
+ if err != nil {
+ listen.Close()
+ ctl.Close()
+ data.Close()
+ return nil, err
+ }
+ return newFD(fd.net, name, listen, ctl, data, fd.laddr, raddr)
+}
+
+func isWildcard(a Addr) bool {
+ var wildcard bool
+ switch a := a.(type) {
+ case *TCPAddr:
+ wildcard = a.isWildcard()
+ case *UDPAddr:
+ wildcard = a.isWildcard()
+ case *IPAddr:
+ wildcard = a.isWildcard()
+ }
+ return wildcard
+}
+
+func toLocal(a Addr, net string) Addr {
+ switch a := a.(type) {
+ case *TCPAddr:
+ a.IP = loopbackIP(net)
+ case *UDPAddr:
+ a.IP = loopbackIP(net)
+ case *IPAddr:
+ a.IP = loopbackIP(net)
+ }
+ return a
+}
+
+// plan9LocalAddr returns a Plan 9 local address string.
+// See setladdrport at https://9p.io/sources/plan9/sys/src/9/ip/devip.c.
+func plan9LocalAddr(addr Addr) string {
+ var ip IP
+ port := 0
+ switch a := addr.(type) {
+ case *TCPAddr:
+ if a != nil {
+ ip = a.IP
+ port = a.Port
+ }
+ case *UDPAddr:
+ if a != nil {
+ ip = a.IP
+ port = a.Port
+ }
+ }
+ if len(ip) == 0 || ip.IsUnspecified() {
+ if port == 0 {
+ return ""
+ }
+ return strconv.Itoa(port)
+ }
+ return ip.String() + "!" + strconv.Itoa(port)
+}
+
+func hangupCtlWrite(ctx context.Context, proto string, ctl *os.File, msg string) error {
+ if proto != "tcp" {
+ _, err := ctl.WriteString(msg)
+ return err
+ }
+ written := make(chan struct{})
+ errc := make(chan error)
+ go func() {
+ select {
+ case <-ctx.Done():
+ ctl.WriteString("hangup")
+ errc <- mapErr(ctx.Err())
+ case <-written:
+ errc <- nil
+ }
+ }()
+ _, err := ctl.WriteString(msg)
+ close(written)
+ if e := <-errc; err == nil && e != nil { // we hung up
+ return e
+ }
+ return err
+}
diff --git a/go/src/net/ipsock_plan9_test.go b/go/src/net/ipsock_plan9_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..e5fb9ff965dd8600d468f3e833e0b816e8e6f9b5
--- /dev/null
+++ b/go/src/net/ipsock_plan9_test.go
@@ -0,0 +1,29 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import "testing"
+
+func TestTCP4ListenZero(t *testing.T) {
+ l, err := Listen("tcp4", "0.0.0.0:0")
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer l.Close()
+ if a := l.Addr(); isNotIPv4(a) {
+ t.Errorf("address does not contain IPv4: %v", a)
+ }
+}
+
+func TestUDP4ListenZero(t *testing.T) {
+ c, err := ListenPacket("udp4", "0.0.0.0:0")
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer c.Close()
+ if a := c.LocalAddr(); isNotIPv4(a) {
+ t.Errorf("address does not contain IPv4: %v", a)
+ }
+}
diff --git a/go/src/net/ipsock_posix.go b/go/src/net/ipsock_posix.go
new file mode 100644
index 0000000000000000000000000000000000000000..1ed37d7e6eaf251968a931e6f93443b76ea833ed
--- /dev/null
+++ b/go/src/net/ipsock_posix.go
@@ -0,0 +1,269 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || js || wasip1 || windows
+
+package net
+
+import (
+ "context"
+ "internal/poll"
+ "net/netip"
+ "runtime"
+ "syscall"
+ _ "unsafe" // for linkname
+)
+
+// probe probes IPv4, IPv6 and IPv4-mapped IPv6 communication
+// capabilities which are controlled by the IPV6_V6ONLY socket option
+// and kernel configuration.
+//
+// Should we try to use the IPv4 socket interface if we're only
+// dealing with IPv4 sockets? As long as the host system understands
+// IPv4-mapped IPv6, it's okay to pass IPv4-mapped IPv6 addresses to
+// the IPv6 interface. That simplifies our code and is most
+// general. Unfortunately, we need to run on kernels built without
+// IPv6 support too. So probe the kernel to figure it out.
+func (p *ipStackCapabilities) probe() {
+ switch runtime.GOOS {
+ case "js", "wasip1":
+ // Both ipv4 and ipv6 are faked; see net_fake.go.
+ p.ipv4Enabled = true
+ p.ipv6Enabled = true
+ p.ipv4MappedIPv6Enabled = true
+ return
+ }
+
+ s, err := sysSocket(syscall.AF_INET, syscall.SOCK_STREAM, syscall.IPPROTO_TCP)
+ switch err {
+ case syscall.EAFNOSUPPORT, syscall.EPROTONOSUPPORT:
+ case nil:
+ poll.CloseFunc(s)
+ p.ipv4Enabled = true
+ }
+ var probes = []struct {
+ laddr TCPAddr
+ value int
+ }{
+ // IPv6 communication capability
+ {laddr: TCPAddr{IP: ParseIP("::1")}, value: 1},
+ // IPv4-mapped IPv6 address communication capability
+ {laddr: TCPAddr{IP: IPv4(127, 0, 0, 1)}, value: 0},
+ }
+ switch runtime.GOOS {
+ case "dragonfly", "openbsd":
+ // The latest DragonFly BSD and OpenBSD kernels don't
+ // support IPV6_V6ONLY=0. They always return an error
+ // and we don't need to probe the capability.
+ probes = probes[:1]
+ }
+ for i := range probes {
+ s, err := sysSocket(syscall.AF_INET6, syscall.SOCK_STREAM, syscall.IPPROTO_TCP)
+ if err != nil {
+ continue
+ }
+ defer poll.CloseFunc(s)
+ syscall.SetsockoptInt(s, syscall.IPPROTO_IPV6, syscall.IPV6_V6ONLY, probes[i].value)
+ sa, err := probes[i].laddr.sockaddr(syscall.AF_INET6)
+ if err != nil {
+ continue
+ }
+ if err := syscall.Bind(s, sa); err != nil {
+ continue
+ }
+ if i == 0 {
+ p.ipv6Enabled = true
+ } else {
+ p.ipv4MappedIPv6Enabled = true
+ }
+ }
+}
+
+// favoriteAddrFamily returns the appropriate address family for the
+// given network, laddr, raddr and mode.
+//
+// If mode indicates "listen" and laddr is a wildcard, we assume that
+// the user wants to make a passive-open connection with a wildcard
+// address family, both AF_INET and AF_INET6, and a wildcard address
+// like the following:
+//
+// - A listen for a wildcard communication domain, "tcp" or
+// "udp", with a wildcard address: If the platform supports
+// both IPv6 and IPv4-mapped IPv6 communication capabilities,
+// or does not support IPv4, we use a dual stack, AF_INET6 and
+// IPV6_V6ONLY=0, wildcard address listen. The dual stack
+// wildcard address listen may fall back to an IPv6-only,
+// AF_INET6 and IPV6_V6ONLY=1, wildcard address listen.
+// Otherwise we prefer an IPv4-only, AF_INET, wildcard address
+// listen.
+//
+// - A listen for a wildcard communication domain, "tcp" or
+// "udp", with an IPv4 wildcard address: same as above.
+//
+// - A listen for a wildcard communication domain, "tcp" or
+// "udp", with an IPv6 wildcard address: same as above.
+//
+// - A listen for an IPv4 communication domain, "tcp4" or "udp4",
+// with an IPv4 wildcard address: We use an IPv4-only, AF_INET,
+// wildcard address listen.
+//
+// - A listen for an IPv6 communication domain, "tcp6" or "udp6",
+// with an IPv6 wildcard address: We use an IPv6-only, AF_INET6
+// and IPV6_V6ONLY=1, wildcard address listen.
+//
+// Otherwise guess: If the addresses are IPv4 then returns AF_INET,
+// or else returns AF_INET6. It also returns a boolean value what
+// designates IPV6_V6ONLY option.
+//
+// Note that the latest DragonFly BSD and OpenBSD kernels allow
+// neither "net.inet6.ip6.v6only=1" change nor IPPROTO_IPV6 level
+// IPV6_V6ONLY socket option setting.
+//
+// favoriteAddrFamily should be an internal detail,
+// but widely used packages access it using linkname.
+// Notable members of the hall of shame include:
+// - github.com/database64128/tfo-go/v2
+// - github.com/metacubex/tfo-go
+// - github.com/sagernet/tfo-go
+//
+// Do not remove or change the type signature.
+// See go.dev/issue/67401.
+//
+//go:linkname favoriteAddrFamily
+func favoriteAddrFamily(network string, laddr, raddr sockaddr, mode string) (family int, ipv6only bool) {
+ switch network[len(network)-1] {
+ case '4':
+ return syscall.AF_INET, false
+ case '6':
+ return syscall.AF_INET6, true
+ }
+
+ if mode == "listen" && (laddr == nil || laddr.isWildcard()) {
+ if supportsIPv4map() || !supportsIPv4() {
+ return syscall.AF_INET6, false
+ }
+ if laddr == nil {
+ return syscall.AF_INET, false
+ }
+ return laddr.family(), false
+ }
+
+ if (laddr == nil || laddr.family() == syscall.AF_INET) &&
+ (raddr == nil || raddr.family() == syscall.AF_INET) {
+ return syscall.AF_INET, false
+ }
+ return syscall.AF_INET6, false
+}
+
+func internetSocket(ctx context.Context, net string, laddr, raddr sockaddr, sotype, proto int, mode string, ctrlCtxFn func(context.Context, string, string, syscall.RawConn) error) (fd *netFD, err error) {
+ switch runtime.GOOS {
+ case "aix", "windows", "openbsd", "js", "wasip1":
+ if mode == "dial" && raddr.isWildcard() {
+ raddr = raddr.toLocal(net)
+ }
+ }
+ family, ipv6only := favoriteAddrFamily(net, laddr, raddr, mode)
+ return socket(ctx, net, family, sotype, proto, ipv6only, laddr, raddr, ctrlCtxFn)
+}
+
+func ipToSockaddrInet4(ip IP, port int) (syscall.SockaddrInet4, error) {
+ if len(ip) == 0 {
+ ip = IPv4zero
+ }
+ ip4 := ip.To4()
+ if ip4 == nil {
+ return syscall.SockaddrInet4{}, &AddrError{Err: "non-IPv4 address", Addr: ip.String()}
+ }
+ sa := syscall.SockaddrInet4{Port: port}
+ copy(sa.Addr[:], ip4)
+ return sa, nil
+}
+
+func ipToSockaddrInet6(ip IP, port int, zone string) (syscall.SockaddrInet6, error) {
+ // In general, an IP wildcard address, which is either
+ // "0.0.0.0" or "::", means the entire IP addressing
+ // space. For some historical reason, it is used to
+ // specify "any available address" on some operations
+ // of IP node.
+ //
+ // When the IP node supports IPv4-mapped IPv6 address,
+ // we allow a listener to listen to the wildcard
+ // address of both IP addressing spaces by specifying
+ // IPv6 wildcard address.
+ if len(ip) == 0 || ip.Equal(IPv4zero) {
+ ip = IPv6zero
+ }
+ // We accept any IPv6 address including IPv4-mapped
+ // IPv6 address.
+ ip6 := ip.To16()
+ if ip6 == nil {
+ return syscall.SockaddrInet6{}, &AddrError{Err: "non-IPv6 address", Addr: ip.String()}
+ }
+ sa := syscall.SockaddrInet6{Port: port, ZoneId: uint32(zoneCache.index(zone))}
+ copy(sa.Addr[:], ip6)
+ return sa, nil
+}
+
+// ipToSockaddr should be an internal detail,
+// but widely used packages access it using linkname.
+// Notable members of the hall of shame include:
+// - github.com/database64128/tfo-go/v2
+// - github.com/metacubex/tfo-go
+// - github.com/sagernet/tfo-go
+//
+// Do not remove or change the type signature.
+// See go.dev/issue/67401.
+//
+//go:linkname ipToSockaddr
+func ipToSockaddr(family int, ip IP, port int, zone string) (syscall.Sockaddr, error) {
+ switch family {
+ case syscall.AF_INET:
+ sa, err := ipToSockaddrInet4(ip, port)
+ if err != nil {
+ return nil, err
+ }
+ return &sa, nil
+ case syscall.AF_INET6:
+ sa, err := ipToSockaddrInet6(ip, port, zone)
+ if err != nil {
+ return nil, err
+ }
+ return &sa, nil
+ }
+ return nil, &AddrError{Err: "invalid address family", Addr: ip.String()}
+}
+
+func addrPortToSockaddrInet4(ap netip.AddrPort) (syscall.SockaddrInet4, error) {
+ // ipToSockaddrInet4 has special handling here for zero length slices.
+ // We do not, because netip has no concept of a generic zero IP address.
+ //
+ // addr is allowed to be an IPv4-mapped IPv6 address.
+ // As4 will unmap it to an IPv4 address.
+ // The error message is kept consistent with ipToSockaddrInet4.
+ addr := ap.Addr()
+ if !addr.Is4() && !addr.Is4In6() {
+ return syscall.SockaddrInet4{}, &AddrError{Err: "non-IPv4 address", Addr: addr.String()}
+ }
+ sa := syscall.SockaddrInet4{
+ Addr: addr.As4(),
+ Port: int(ap.Port()),
+ }
+ return sa, nil
+}
+
+func addrPortToSockaddrInet6(ap netip.AddrPort) (syscall.SockaddrInet6, error) {
+ // ipToSockaddrInet6 has special handling here for zero length slices.
+ // We do not, because netip has no concept of a generic zero IP address.
+ //
+ // addr is allowed to be an IPv4 address, because As16 will convert it
+ // to an IPv4-mapped IPv6 address.
+ // The error message is kept consistent with ipToSockaddrInet6.
+ addr := ap.Addr()
+ sa := syscall.SockaddrInet6{
+ Addr: addr.As16(),
+ Port: int(ap.Port()),
+ ZoneId: uint32(zoneCache.index(addr.Zone())),
+ }
+ return sa, nil
+}
diff --git a/go/src/net/ipsock_test.go b/go/src/net/ipsock_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..aede354844748449039aa71d0541ac70a0225f1c
--- /dev/null
+++ b/go/src/net/ipsock_test.go
@@ -0,0 +1,282 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "reflect"
+ "testing"
+)
+
+var testInetaddr = func(ip IPAddr) Addr { return &TCPAddr{IP: ip.IP, Port: 5682, Zone: ip.Zone} }
+
+var addrListTests = []struct {
+ filter func(IPAddr) bool
+ ips []IPAddr
+ inetaddr func(IPAddr) Addr
+ first Addr
+ primaries addrList
+ fallbacks addrList
+ err error
+}{
+ {
+ nil,
+ []IPAddr{
+ {IP: IPv4(127, 0, 0, 1)},
+ {IP: IPv6loopback},
+ },
+ testInetaddr,
+ &TCPAddr{IP: IPv4(127, 0, 0, 1), Port: 5682},
+ addrList{&TCPAddr{IP: IPv4(127, 0, 0, 1), Port: 5682}},
+ addrList{&TCPAddr{IP: IPv6loopback, Port: 5682}},
+ nil,
+ },
+ {
+ nil,
+ []IPAddr{
+ {IP: IPv6loopback},
+ {IP: IPv4(127, 0, 0, 1)},
+ },
+ testInetaddr,
+ &TCPAddr{IP: IPv4(127, 0, 0, 1), Port: 5682},
+ addrList{&TCPAddr{IP: IPv6loopback, Port: 5682}},
+ addrList{&TCPAddr{IP: IPv4(127, 0, 0, 1), Port: 5682}},
+ nil,
+ },
+ {
+ nil,
+ []IPAddr{
+ {IP: IPv4(127, 0, 0, 1)},
+ {IP: IPv4(192, 168, 0, 1)},
+ },
+ testInetaddr,
+ &TCPAddr{IP: IPv4(127, 0, 0, 1), Port: 5682},
+ addrList{
+ &TCPAddr{IP: IPv4(127, 0, 0, 1), Port: 5682},
+ &TCPAddr{IP: IPv4(192, 168, 0, 1), Port: 5682},
+ },
+ nil,
+ nil,
+ },
+ {
+ nil,
+ []IPAddr{
+ {IP: IPv6loopback},
+ {IP: ParseIP("fe80::1"), Zone: "eth0"},
+ },
+ testInetaddr,
+ &TCPAddr{IP: IPv6loopback, Port: 5682},
+ addrList{
+ &TCPAddr{IP: IPv6loopback, Port: 5682},
+ &TCPAddr{IP: ParseIP("fe80::1"), Port: 5682, Zone: "eth0"},
+ },
+ nil,
+ nil,
+ },
+ {
+ nil,
+ []IPAddr{
+ {IP: IPv4(127, 0, 0, 1)},
+ {IP: IPv4(192, 168, 0, 1)},
+ {IP: IPv6loopback},
+ {IP: ParseIP("fe80::1"), Zone: "eth0"},
+ },
+ testInetaddr,
+ &TCPAddr{IP: IPv4(127, 0, 0, 1), Port: 5682},
+ addrList{
+ &TCPAddr{IP: IPv4(127, 0, 0, 1), Port: 5682},
+ &TCPAddr{IP: IPv4(192, 168, 0, 1), Port: 5682},
+ },
+ addrList{
+ &TCPAddr{IP: IPv6loopback, Port: 5682},
+ &TCPAddr{IP: ParseIP("fe80::1"), Port: 5682, Zone: "eth0"},
+ },
+ nil,
+ },
+ {
+ nil,
+ []IPAddr{
+ {IP: IPv6loopback},
+ {IP: ParseIP("fe80::1"), Zone: "eth0"},
+ {IP: IPv4(127, 0, 0, 1)},
+ {IP: IPv4(192, 168, 0, 1)},
+ },
+ testInetaddr,
+ &TCPAddr{IP: IPv4(127, 0, 0, 1), Port: 5682},
+ addrList{
+ &TCPAddr{IP: IPv6loopback, Port: 5682},
+ &TCPAddr{IP: ParseIP("fe80::1"), Port: 5682, Zone: "eth0"},
+ },
+ addrList{
+ &TCPAddr{IP: IPv4(127, 0, 0, 1), Port: 5682},
+ &TCPAddr{IP: IPv4(192, 168, 0, 1), Port: 5682},
+ },
+ nil,
+ },
+ {
+ nil,
+ []IPAddr{
+ {IP: IPv4(127, 0, 0, 1)},
+ {IP: IPv6loopback},
+ {IP: IPv4(192, 168, 0, 1)},
+ {IP: ParseIP("fe80::1"), Zone: "eth0"},
+ },
+ testInetaddr,
+ &TCPAddr{IP: IPv4(127, 0, 0, 1), Port: 5682},
+ addrList{
+ &TCPAddr{IP: IPv4(127, 0, 0, 1), Port: 5682},
+ &TCPAddr{IP: IPv4(192, 168, 0, 1), Port: 5682},
+ },
+ addrList{
+ &TCPAddr{IP: IPv6loopback, Port: 5682},
+ &TCPAddr{IP: ParseIP("fe80::1"), Port: 5682, Zone: "eth0"},
+ },
+ nil,
+ },
+ {
+ nil,
+ []IPAddr{
+ {IP: IPv6loopback},
+ {IP: IPv4(127, 0, 0, 1)},
+ {IP: ParseIP("fe80::1"), Zone: "eth0"},
+ {IP: IPv4(192, 168, 0, 1)},
+ },
+ testInetaddr,
+ &TCPAddr{IP: IPv4(127, 0, 0, 1), Port: 5682},
+ addrList{
+ &TCPAddr{IP: IPv6loopback, Port: 5682},
+ &TCPAddr{IP: ParseIP("fe80::1"), Port: 5682, Zone: "eth0"},
+ },
+ addrList{
+ &TCPAddr{IP: IPv4(127, 0, 0, 1), Port: 5682},
+ &TCPAddr{IP: IPv4(192, 168, 0, 1), Port: 5682},
+ },
+ nil,
+ },
+
+ {
+ ipv4only,
+ []IPAddr{
+ {IP: IPv4(127, 0, 0, 1)},
+ {IP: IPv6loopback},
+ },
+ testInetaddr,
+ &TCPAddr{IP: IPv4(127, 0, 0, 1), Port: 5682},
+ addrList{&TCPAddr{IP: IPv4(127, 0, 0, 1), Port: 5682}},
+ nil,
+ nil,
+ },
+ {
+ ipv4only,
+ []IPAddr{
+ {IP: IPv6loopback},
+ {IP: IPv4(127, 0, 0, 1)},
+ },
+ testInetaddr,
+ &TCPAddr{IP: IPv4(127, 0, 0, 1), Port: 5682},
+ addrList{&TCPAddr{IP: IPv4(127, 0, 0, 1), Port: 5682}},
+ nil,
+ nil,
+ },
+
+ {
+ ipv6only,
+ []IPAddr{
+ {IP: IPv4(127, 0, 0, 1)},
+ {IP: IPv6loopback},
+ },
+ testInetaddr,
+ &TCPAddr{IP: IPv6loopback, Port: 5682},
+ addrList{&TCPAddr{IP: IPv6loopback, Port: 5682}},
+ nil,
+ nil,
+ },
+ {
+ ipv6only,
+ []IPAddr{
+ {IP: IPv6loopback},
+ {IP: IPv4(127, 0, 0, 1)},
+ },
+ testInetaddr,
+ &TCPAddr{IP: IPv6loopback, Port: 5682},
+ addrList{&TCPAddr{IP: IPv6loopback, Port: 5682}},
+ nil,
+ nil,
+ },
+
+ {nil, nil, testInetaddr, nil, nil, nil, &AddrError{errNoSuitableAddress.Error(), "ADDR"}},
+
+ {ipv4only, nil, testInetaddr, nil, nil, nil, &AddrError{errNoSuitableAddress.Error(), "ADDR"}},
+ {ipv4only, []IPAddr{{IP: IPv6loopback}}, testInetaddr, nil, nil, nil, &AddrError{errNoSuitableAddress.Error(), "ADDR"}},
+
+ {ipv6only, nil, testInetaddr, nil, nil, nil, &AddrError{errNoSuitableAddress.Error(), "ADDR"}},
+ {ipv6only, []IPAddr{{IP: IPv4(127, 0, 0, 1)}}, testInetaddr, nil, nil, nil, &AddrError{errNoSuitableAddress.Error(), "ADDR"}},
+}
+
+func TestAddrList(t *testing.T) {
+ if !supportsIPv4() || !supportsIPv6() {
+ t.Skip("both IPv4 and IPv6 are required")
+ }
+
+ for i, tt := range addrListTests {
+ addrs, err := filterAddrList(tt.filter, tt.ips, tt.inetaddr, "ADDR")
+ if !reflect.DeepEqual(err, tt.err) {
+ t.Errorf("#%v: got %v; want %v", i, err, tt.err)
+ }
+ if tt.err != nil {
+ if len(addrs) != 0 {
+ t.Errorf("#%v: got %v; want 0", i, len(addrs))
+ }
+ continue
+ }
+ first := addrs.first(isIPv4)
+ if !reflect.DeepEqual(first, tt.first) {
+ t.Errorf("#%v: got %v; want %v", i, first, tt.first)
+ }
+ primaries, fallbacks := addrs.partition(isIPv4)
+ if !reflect.DeepEqual(primaries, tt.primaries) {
+ t.Errorf("#%v: got %v; want %v", i, primaries, tt.primaries)
+ }
+ if !reflect.DeepEqual(fallbacks, tt.fallbacks) {
+ t.Errorf("#%v: got %v; want %v", i, fallbacks, tt.fallbacks)
+ }
+ expectedLen := len(primaries) + len(fallbacks)
+ if len(addrs) != expectedLen {
+ t.Errorf("#%v: got %v; want %v", i, len(addrs), expectedLen)
+ }
+ }
+}
+
+func TestAddrListPartition(t *testing.T) {
+ addrs := addrList{
+ &IPAddr{IP: ParseIP("fe80::"), Zone: "eth0"},
+ &IPAddr{IP: ParseIP("fe80::1"), Zone: "eth0"},
+ &IPAddr{IP: ParseIP("fe80::2"), Zone: "eth0"},
+ }
+ cases := []struct {
+ lastByte byte
+ primaries addrList
+ fallbacks addrList
+ }{
+ {0, addrList{addrs[0]}, addrList{addrs[1], addrs[2]}},
+ {1, addrList{addrs[0], addrs[2]}, addrList{addrs[1]}},
+ {2, addrList{addrs[0], addrs[1]}, addrList{addrs[2]}},
+ {3, addrList{addrs[0], addrs[1], addrs[2]}, nil},
+ }
+ for i, tt := range cases {
+ // Inverting the function's output should not affect the outcome.
+ for _, invert := range []bool{false, true} {
+ primaries, fallbacks := addrs.partition(func(a Addr) bool {
+ ip := a.(*IPAddr).IP
+ return (ip[len(ip)-1] == tt.lastByte) != invert
+ })
+ if !reflect.DeepEqual(primaries, tt.primaries) {
+ t.Errorf("#%v: got %v; want %v", i, primaries, tt.primaries)
+ }
+ if !reflect.DeepEqual(fallbacks, tt.fallbacks) {
+ t.Errorf("#%v: got %v; want %v", i, fallbacks, tt.fallbacks)
+ }
+ }
+ }
+}
diff --git a/go/src/net/listen_test.go b/go/src/net/listen_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..59c1277a97966cb9e565c16e0e5968abd7dc1bf2
--- /dev/null
+++ b/go/src/net/listen_test.go
@@ -0,0 +1,751 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !plan9
+
+package net
+
+import (
+ "fmt"
+ "internal/testenv"
+ "os"
+ "runtime"
+ "syscall"
+ "testing"
+ "time"
+)
+
+func (ln *TCPListener) port() string {
+ _, port, err := SplitHostPort(ln.Addr().String())
+ if err != nil {
+ return ""
+ }
+ return port
+}
+
+func (c *UDPConn) port() string {
+ _, port, err := SplitHostPort(c.LocalAddr().String())
+ if err != nil {
+ return ""
+ }
+ return port
+}
+
+var tcpListenerTests = []struct {
+ network string
+ address string
+}{
+ {"tcp", ""},
+ {"tcp", "0.0.0.0"},
+ {"tcp", "::ffff:0.0.0.0"},
+ {"tcp", "::"},
+
+ {"tcp", "127.0.0.1"},
+ {"tcp", "::ffff:127.0.0.1"},
+ {"tcp", "::1"},
+
+ {"tcp4", ""},
+ {"tcp4", "0.0.0.0"},
+ {"tcp4", "::ffff:0.0.0.0"},
+
+ {"tcp4", "127.0.0.1"},
+ {"tcp4", "::ffff:127.0.0.1"},
+
+ {"tcp6", ""},
+ {"tcp6", "::"},
+
+ {"tcp6", "::1"},
+}
+
+// TestTCPListener tests both single and double listen to a test
+// listener with same address family, same listening address and
+// same port.
+func TestTCPListener(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+
+ for _, tt := range tcpListenerTests {
+ if !testableListenArgs(tt.network, JoinHostPort(tt.address, "0"), "") {
+ t.Logf("skipping %s test", tt.network+" "+tt.address)
+ continue
+ }
+
+ ln1, err := Listen(tt.network, JoinHostPort(tt.address, "0"))
+ if err != nil {
+ t.Fatal(err)
+ }
+ if err := checkFirstListener(tt.network, ln1); err != nil {
+ ln1.Close()
+ t.Fatal(err)
+ }
+ ln2, err := Listen(tt.network, JoinHostPort(tt.address, ln1.(*TCPListener).port()))
+ if err == nil {
+ ln2.Close()
+ }
+ if err := checkSecondListener(tt.network, tt.address, err); err != nil {
+ ln1.Close()
+ t.Fatal(err)
+ }
+ ln1.Close()
+ }
+}
+
+var udpListenerTests = []struct {
+ network string
+ address string
+}{
+ {"udp", ""},
+ {"udp", "0.0.0.0"},
+ {"udp", "::ffff:0.0.0.0"},
+ {"udp", "::"},
+
+ {"udp", "127.0.0.1"},
+ {"udp", "::ffff:127.0.0.1"},
+ {"udp", "::1"},
+
+ {"udp4", ""},
+ {"udp4", "0.0.0.0"},
+ {"udp4", "::ffff:0.0.0.0"},
+
+ {"udp4", "127.0.0.1"},
+ {"udp4", "::ffff:127.0.0.1"},
+
+ {"udp6", ""},
+ {"udp6", "::"},
+
+ {"udp6", "::1"},
+}
+
+// TestUDPListener tests both single and double listen to a test
+// listener with same address family, same listening address and
+// same port.
+func TestUDPListener(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+
+ for _, tt := range udpListenerTests {
+ if !testableListenArgs(tt.network, JoinHostPort(tt.address, "0"), "") {
+ t.Logf("skipping %s test", tt.network+" "+tt.address)
+ continue
+ }
+
+ c1, err := ListenPacket(tt.network, JoinHostPort(tt.address, "0"))
+ if err != nil {
+ t.Fatal(err)
+ }
+ if err := checkFirstListener(tt.network, c1); err != nil {
+ c1.Close()
+ t.Fatal(err)
+ }
+ c2, err := ListenPacket(tt.network, JoinHostPort(tt.address, c1.(*UDPConn).port()))
+ if err == nil {
+ c2.Close()
+ }
+ if err := checkSecondListener(tt.network, tt.address, err); err != nil {
+ c1.Close()
+ t.Fatal(err)
+ }
+ c1.Close()
+ }
+}
+
+var dualStackTCPListenerTests = []struct {
+ network1, address1 string // first listener
+ network2, address2 string // second listener
+ xerr error // expected error value, nil or other
+}{
+ // Test cases and expected results for the attempting 2nd listen on the same port
+ // 1st listen 2nd listen darwin freebsd linux openbsd
+ // ------------------------------------------------------------------------------------
+ // "tcp" "" "tcp" "" - - - -
+ // "tcp" "" "tcp" "0.0.0.0" - - - -
+ // "tcp" "0.0.0.0" "tcp" "" - - - -
+ // ------------------------------------------------------------------------------------
+ // "tcp" "" "tcp" "[::]" - - - ok
+ // "tcp" "[::]" "tcp" "" - - - ok
+ // "tcp" "0.0.0.0" "tcp" "[::]" - - - ok
+ // "tcp" "[::]" "tcp" "0.0.0.0" - - - ok
+ // "tcp" "[::ffff:0.0.0.0]" "tcp" "[::]" - - - ok
+ // "tcp" "[::]" "tcp" "[::ffff:0.0.0.0]" - - - ok
+ // ------------------------------------------------------------------------------------
+ // "tcp4" "" "tcp6" "" ok ok ok ok
+ // "tcp6" "" "tcp4" "" ok ok ok ok
+ // "tcp4" "0.0.0.0" "tcp6" "[::]" ok ok ok ok
+ // "tcp6" "[::]" "tcp4" "0.0.0.0" ok ok ok ok
+ // ------------------------------------------------------------------------------------
+ // "tcp" "127.0.0.1" "tcp" "[::1]" ok ok ok ok
+ // "tcp" "[::1]" "tcp" "127.0.0.1" ok ok ok ok
+ // "tcp4" "127.0.0.1" "tcp6" "[::1]" ok ok ok ok
+ // "tcp6" "[::1]" "tcp4" "127.0.0.1" ok ok ok ok
+ //
+ // Platform default configurations:
+ // darwin, kernel version 11.3.0
+ // net.inet6.ip6.v6only=0 (overridable by sysctl or IPV6_V6ONLY option)
+ // freebsd, kernel version 8.2
+ // net.inet6.ip6.v6only=1 (overridable by sysctl or IPV6_V6ONLY option)
+ // linux, kernel version 3.0.0
+ // net.ipv6.bindv6only=0 (overridable by sysctl or IPV6_V6ONLY option)
+ // openbsd, kernel version 5.0
+ // net.inet6.ip6.v6only=1 (overriding is prohibited)
+
+ {"tcp", "", "tcp", "", syscall.EADDRINUSE},
+ {"tcp", "", "tcp", "0.0.0.0", syscall.EADDRINUSE},
+ {"tcp", "0.0.0.0", "tcp", "", syscall.EADDRINUSE},
+
+ {"tcp", "", "tcp", "::", syscall.EADDRINUSE},
+ {"tcp", "::", "tcp", "", syscall.EADDRINUSE},
+ {"tcp", "0.0.0.0", "tcp", "::", syscall.EADDRINUSE},
+ {"tcp", "::", "tcp", "0.0.0.0", syscall.EADDRINUSE},
+ {"tcp", "::ffff:0.0.0.0", "tcp", "::", syscall.EADDRINUSE},
+ {"tcp", "::", "tcp", "::ffff:0.0.0.0", syscall.EADDRINUSE},
+
+ {"tcp4", "", "tcp6", "", nil},
+ {"tcp6", "", "tcp4", "", nil},
+ {"tcp4", "0.0.0.0", "tcp6", "::", nil},
+ {"tcp6", "::", "tcp4", "0.0.0.0", nil},
+
+ {"tcp", "127.0.0.1", "tcp", "::1", nil},
+ {"tcp", "::1", "tcp", "127.0.0.1", nil},
+ {"tcp4", "127.0.0.1", "tcp6", "::1", nil},
+ {"tcp6", "::1", "tcp4", "127.0.0.1", nil},
+}
+
+// TestDualStackTCPListener tests both single and double listen
+// to a test listener with various address families, different
+// listening address and same port.
+//
+// On DragonFly BSD, we expect the kernel version of node under test
+// to be greater than or equal to 4.4.
+func TestDualStackTCPListener(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+ if !supportsIPv4() || !supportsIPv6() {
+ t.Skip("both IPv4 and IPv6 are required")
+ }
+
+ for _, tt := range dualStackTCPListenerTests {
+ if !testableListenArgs(tt.network1, JoinHostPort(tt.address1, "0"), "") {
+ t.Logf("skipping %s test", tt.network1+" "+tt.address1)
+ continue
+ }
+
+ if !supportsIPv4map() && differentWildcardAddr(tt.address1, tt.address2) {
+ tt.xerr = nil
+ }
+ var firstErr, secondErr error
+ for i := 0; i < 5; i++ {
+ lns, err := newDualStackListener()
+ if err != nil {
+ t.Fatal(err)
+ }
+ port := lns[0].port()
+ for _, ln := range lns {
+ ln.Close()
+ }
+ var ln1 Listener
+ ln1, firstErr = Listen(tt.network1, JoinHostPort(tt.address1, port))
+ if firstErr != nil {
+ continue
+ }
+ if err := checkFirstListener(tt.network1, ln1); err != nil {
+ ln1.Close()
+ t.Fatal(err)
+ }
+ ln2, err := Listen(tt.network2, JoinHostPort(tt.address2, ln1.(*TCPListener).port()))
+ if err == nil {
+ ln2.Close()
+ }
+ if secondErr = checkDualStackSecondListener(tt.network2, tt.address2, err, tt.xerr); secondErr != nil {
+ ln1.Close()
+ continue
+ }
+ ln1.Close()
+ break
+ }
+ if firstErr != nil {
+ t.Error(firstErr)
+ }
+ if secondErr != nil {
+ t.Error(secondErr)
+ }
+ }
+}
+
+var dualStackUDPListenerTests = []struct {
+ network1, address1 string // first listener
+ network2, address2 string // second listener
+ xerr error // expected error value, nil or other
+}{
+ {"udp", "", "udp", "", syscall.EADDRINUSE},
+ {"udp", "", "udp", "0.0.0.0", syscall.EADDRINUSE},
+ {"udp", "0.0.0.0", "udp", "", syscall.EADDRINUSE},
+
+ {"udp", "", "udp", "::", syscall.EADDRINUSE},
+ {"udp", "::", "udp", "", syscall.EADDRINUSE},
+ {"udp", "0.0.0.0", "udp", "::", syscall.EADDRINUSE},
+ {"udp", "::", "udp", "0.0.0.0", syscall.EADDRINUSE},
+ {"udp", "::ffff:0.0.0.0", "udp", "::", syscall.EADDRINUSE},
+ {"udp", "::", "udp", "::ffff:0.0.0.0", syscall.EADDRINUSE},
+
+ {"udp4", "", "udp6", "", nil},
+ {"udp6", "", "udp4", "", nil},
+ {"udp4", "0.0.0.0", "udp6", "::", nil},
+ {"udp6", "::", "udp4", "0.0.0.0", nil},
+
+ {"udp", "127.0.0.1", "udp", "::1", nil},
+ {"udp", "::1", "udp", "127.0.0.1", nil},
+ {"udp4", "127.0.0.1", "udp6", "::1", nil},
+ {"udp6", "::1", "udp4", "127.0.0.1", nil},
+}
+
+// TestDualStackUDPListener tests both single and double listen
+// to a test listener with various address families, different
+// listening address and same port.
+//
+// On DragonFly BSD, we expect the kernel version of node under test
+// to be greater than or equal to 4.4.
+func TestDualStackUDPListener(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+ if !supportsIPv4() || !supportsIPv6() {
+ t.Skip("both IPv4 and IPv6 are required")
+ }
+
+ for _, tt := range dualStackUDPListenerTests {
+ if !testableListenArgs(tt.network1, JoinHostPort(tt.address1, "0"), "") {
+ t.Logf("skipping %s test", tt.network1+" "+tt.address1)
+ continue
+ }
+
+ if !supportsIPv4map() && differentWildcardAddr(tt.address1, tt.address2) {
+ tt.xerr = nil
+ }
+ var firstErr, secondErr error
+ for i := 0; i < 5; i++ {
+ cs, err := newDualStackPacketListener()
+ if err != nil {
+ t.Fatal(err)
+ }
+ port := cs[0].port()
+ for _, c := range cs {
+ c.Close()
+ }
+ var c1 PacketConn
+ c1, firstErr = ListenPacket(tt.network1, JoinHostPort(tt.address1, port))
+ if firstErr != nil {
+ continue
+ }
+ if err := checkFirstListener(tt.network1, c1); err != nil {
+ c1.Close()
+ t.Fatal(err)
+ }
+ c2, err := ListenPacket(tt.network2, JoinHostPort(tt.address2, c1.(*UDPConn).port()))
+ if err == nil {
+ c2.Close()
+ }
+ if secondErr = checkDualStackSecondListener(tt.network2, tt.address2, err, tt.xerr); secondErr != nil {
+ c1.Close()
+ continue
+ }
+ c1.Close()
+ break
+ }
+ if firstErr != nil {
+ t.Error(firstErr)
+ }
+ if secondErr != nil {
+ t.Error(secondErr)
+ }
+ }
+}
+
+func differentWildcardAddr(i, j string) bool {
+ if (i == "" || i == "0.0.0.0" || i == "::ffff:0.0.0.0") && (j == "" || j == "0.0.0.0" || j == "::ffff:0.0.0.0") {
+ return false
+ }
+ if i == "[::]" && j == "[::]" {
+ return false
+ }
+ return true
+}
+
+func checkFirstListener(network string, ln any) error {
+ switch network {
+ case "tcp":
+ fd := ln.(*TCPListener).fd
+ if err := checkDualStackAddrFamily(fd); err != nil {
+ return err
+ }
+ case "tcp4":
+ fd := ln.(*TCPListener).fd
+ if fd.family != syscall.AF_INET {
+ return fmt.Errorf("%v got %v; want %v", fd.laddr, fd.family, syscall.AF_INET)
+ }
+ case "tcp6":
+ fd := ln.(*TCPListener).fd
+ if fd.family != syscall.AF_INET6 {
+ return fmt.Errorf("%v got %v; want %v", fd.laddr, fd.family, syscall.AF_INET6)
+ }
+ case "udp":
+ fd := ln.(*UDPConn).fd
+ if err := checkDualStackAddrFamily(fd); err != nil {
+ return err
+ }
+ case "udp4":
+ fd := ln.(*UDPConn).fd
+ if fd.family != syscall.AF_INET {
+ return fmt.Errorf("%v got %v; want %v", fd.laddr, fd.family, syscall.AF_INET)
+ }
+ case "udp6":
+ fd := ln.(*UDPConn).fd
+ if fd.family != syscall.AF_INET6 {
+ return fmt.Errorf("%v got %v; want %v", fd.laddr, fd.family, syscall.AF_INET6)
+ }
+ default:
+ return UnknownNetworkError(network)
+ }
+ return nil
+}
+
+func checkSecondListener(network, address string, err error) error {
+ switch network {
+ case "tcp", "tcp4", "tcp6":
+ if err == nil {
+ return fmt.Errorf("%s should fail", network+" "+address)
+ }
+ case "udp", "udp4", "udp6":
+ if err == nil {
+ return fmt.Errorf("%s should fail", network+" "+address)
+ }
+ default:
+ return UnknownNetworkError(network)
+ }
+ return nil
+}
+
+func checkDualStackSecondListener(network, address string, err, xerr error) error {
+ switch network {
+ case "tcp", "tcp4", "tcp6":
+ if xerr == nil && err != nil || xerr != nil && err == nil {
+ return fmt.Errorf("%s got %v; want %v", network+" "+address, err, xerr)
+ }
+ case "udp", "udp4", "udp6":
+ if xerr == nil && err != nil || xerr != nil && err == nil {
+ return fmt.Errorf("%s got %v; want %v", network+" "+address, err, xerr)
+ }
+ default:
+ return UnknownNetworkError(network)
+ }
+ return nil
+}
+
+func checkDualStackAddrFamily(fd *netFD) error {
+ switch a := fd.laddr.(type) {
+ case *TCPAddr:
+ // If a node under test supports both IPv6 capability
+ // and IPv6 IPv4-mapping capability, we can assume
+ // that the node listens on a wildcard address with an
+ // AF_INET6 socket.
+ if supportsIPv4map() && fd.laddr.(*TCPAddr).isWildcard() {
+ if fd.family != syscall.AF_INET6 {
+ return fmt.Errorf("Listen(%s, %v) returns %v; want %v", fd.net, fd.laddr, fd.family, syscall.AF_INET6)
+ }
+ } else {
+ if fd.family != a.family() {
+ return fmt.Errorf("Listen(%s, %v) returns %v; want %v", fd.net, fd.laddr, fd.family, a.family())
+ }
+ }
+ case *UDPAddr:
+ // If a node under test supports both IPv6 capability
+ // and IPv6 IPv4-mapping capability, we can assume
+ // that the node listens on a wildcard address with an
+ // AF_INET6 socket.
+ if supportsIPv4map() && fd.laddr.(*UDPAddr).isWildcard() {
+ if fd.family != syscall.AF_INET6 {
+ return fmt.Errorf("ListenPacket(%s, %v) returns %v; want %v", fd.net, fd.laddr, fd.family, syscall.AF_INET6)
+ }
+ } else {
+ if fd.family != a.family() {
+ return fmt.Errorf("ListenPacket(%s, %v) returns %v; want %v", fd.net, fd.laddr, fd.family, a.family())
+ }
+ }
+ default:
+ return fmt.Errorf("unexpected protocol address type: %T", a)
+ }
+ return nil
+}
+
+func TestWildWildcardListener(t *testing.T) {
+ testenv.MustHaveExternalNetwork(t)
+
+ switch runtime.GOOS {
+ case "plan9":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+
+ defer func() {
+ if p := recover(); p != nil {
+ t.Fatalf("panicked: %v", p)
+ }
+ }()
+
+ if ln, err := Listen("tcp", ""); err == nil {
+ ln.Close()
+ }
+ if ln, err := ListenPacket("udp", ""); err == nil {
+ ln.Close()
+ }
+ if ln, err := ListenTCP("tcp", nil); err == nil {
+ ln.Close()
+ }
+ if ln, err := ListenUDP("udp", nil); err == nil {
+ ln.Close()
+ }
+ if ln, err := ListenIP("ip:icmp", nil); err == nil {
+ ln.Close()
+ }
+}
+
+var ipv4MulticastListenerTests = []struct {
+ net string
+ gaddr *UDPAddr // see RFC 4727
+}{
+ {"udp", &UDPAddr{IP: IPv4(224, 0, 0, 254), Port: 12345}},
+
+ {"udp4", &UDPAddr{IP: IPv4(224, 0, 0, 254), Port: 12345}},
+}
+
+// TestIPv4MulticastListener tests both single and double listen to a
+// test listener with same address family, same group address and same
+// port.
+func TestIPv4MulticastListener(t *testing.T) {
+ testenv.MustHaveExternalNetwork(t)
+
+ switch runtime.GOOS {
+ case "android", "plan9":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+ if !supportsIPv4() {
+ t.Skip("IPv4 is not supported")
+ }
+
+ closer := func(cs []*UDPConn) {
+ for _, c := range cs {
+ if c != nil {
+ c.Close()
+ }
+ }
+ }
+
+ for _, ifi := range []*Interface{loopbackInterface(), nil} {
+ // Note that multicast interface assignment by system
+ // is not recommended because it usually relies on
+ // routing stuff for finding out an appropriate
+ // nexthop containing both network and link layer
+ // adjacencies.
+ if ifi == nil || !*testIPv4 {
+ continue
+ }
+ for _, tt := range ipv4MulticastListenerTests {
+ var err error
+ cs := make([]*UDPConn, 2)
+ if cs[0], err = ListenMulticastUDP(tt.net, ifi, tt.gaddr); err != nil {
+ t.Fatal(err)
+ }
+ if err := checkMulticastListener(cs[0], tt.gaddr.IP); err != nil {
+ closer(cs)
+ t.Fatal(err)
+ }
+ if cs[1], err = ListenMulticastUDP(tt.net, ifi, tt.gaddr); err != nil {
+ closer(cs)
+ t.Fatal(err)
+ }
+ if err := checkMulticastListener(cs[1], tt.gaddr.IP); err != nil {
+ closer(cs)
+ t.Fatal(err)
+ }
+ closer(cs)
+ }
+ }
+}
+
+var ipv6MulticastListenerTests = []struct {
+ net string
+ gaddr *UDPAddr // see RFC 4727
+}{
+ {"udp", &UDPAddr{IP: ParseIP("ff01::114"), Port: 12345}},
+ {"udp", &UDPAddr{IP: ParseIP("ff02::114"), Port: 12345}},
+ {"udp", &UDPAddr{IP: ParseIP("ff04::114"), Port: 12345}},
+ {"udp", &UDPAddr{IP: ParseIP("ff05::114"), Port: 12345}},
+ {"udp", &UDPAddr{IP: ParseIP("ff08::114"), Port: 12345}},
+ {"udp", &UDPAddr{IP: ParseIP("ff0e::114"), Port: 12345}},
+
+ {"udp6", &UDPAddr{IP: ParseIP("ff01::114"), Port: 12345}},
+ {"udp6", &UDPAddr{IP: ParseIP("ff02::114"), Port: 12345}},
+ {"udp6", &UDPAddr{IP: ParseIP("ff04::114"), Port: 12345}},
+ {"udp6", &UDPAddr{IP: ParseIP("ff05::114"), Port: 12345}},
+ {"udp6", &UDPAddr{IP: ParseIP("ff08::114"), Port: 12345}},
+ {"udp6", &UDPAddr{IP: ParseIP("ff0e::114"), Port: 12345}},
+}
+
+// TestIPv6MulticastListener tests both single and double listen to a
+// test listener with same address family, same group address and same
+// port.
+func TestIPv6MulticastListener(t *testing.T) {
+ testenv.MustHaveExternalNetwork(t)
+
+ switch runtime.GOOS {
+ case "plan9":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+ if !supportsIPv6() {
+ t.Skip("IPv6 is not supported")
+ }
+ // On Windows, the test can be run by non-admin users.
+ if runtime.GOOS != "windows" && os.Getuid() != 0 {
+ t.Skip("must be root")
+ }
+
+ closer := func(cs []*UDPConn) {
+ for _, c := range cs {
+ if c != nil {
+ c.Close()
+ }
+ }
+ }
+
+ for _, ifi := range []*Interface{loopbackInterface(), nil} {
+ // Note that multicast interface assignment by system
+ // is not recommended because it usually relies on
+ // routing stuff for finding out an appropriate
+ // nexthop containing both network and link layer
+ // adjacencies.
+ if ifi == nil && !*testIPv6 {
+ continue
+ }
+ for _, tt := range ipv6MulticastListenerTests {
+ var err error
+ cs := make([]*UDPConn, 2)
+ if cs[0], err = ListenMulticastUDP(tt.net, ifi, tt.gaddr); err != nil {
+ t.Fatal(err)
+ }
+ if err := checkMulticastListener(cs[0], tt.gaddr.IP); err != nil {
+ closer(cs)
+ t.Fatal(err)
+ }
+ if cs[1], err = ListenMulticastUDP(tt.net, ifi, tt.gaddr); err != nil {
+ closer(cs)
+ t.Fatal(err)
+ }
+ if err := checkMulticastListener(cs[1], tt.gaddr.IP); err != nil {
+ closer(cs)
+ t.Fatal(err)
+ }
+ closer(cs)
+ }
+ }
+}
+
+func checkMulticastListener(c *UDPConn, ip IP) error {
+ if ok, err := multicastRIBContains(ip); err != nil {
+ return err
+ } else if !ok {
+ return fmt.Errorf("%s not found in multicast rib", ip.String())
+ }
+ la := c.LocalAddr()
+ if la, ok := la.(*UDPAddr); !ok || la.Port == 0 {
+ return fmt.Errorf("got %v; want a proper address with non-zero port number", la)
+ }
+ return nil
+}
+
+func multicastRIBContains(ip IP) (bool, error) {
+ switch runtime.GOOS {
+ case "aix", "dragonfly", "netbsd", "openbsd", "plan9", "solaris", "illumos":
+ return true, nil // not implemented yet
+ case "linux":
+ if runtime.GOARCH == "arm" || runtime.GOARCH == "alpha" {
+ return true, nil // not implemented yet
+ }
+ }
+ ift, err := Interfaces()
+ if err != nil {
+ return false, err
+ }
+ for _, ifi := range ift {
+ ifmat, err := ifi.MulticastAddrs()
+ if err != nil {
+ return false, err
+ }
+ for _, ifma := range ifmat {
+ if ifma.(*IPAddr).IP.Equal(ip) {
+ return true, nil
+ }
+ }
+ }
+ return false, nil
+}
+
+// Issue 21856.
+func TestClosingListener(t *testing.T) {
+ ln := newLocalListener(t, "tcp")
+ addr := ln.Addr()
+
+ go func() {
+ for {
+ c, err := ln.Accept()
+ if err != nil {
+ return
+ }
+ c.Close()
+ }
+ }()
+
+ // Let the goroutine start. We don't sleep long: if the
+ // goroutine doesn't start, the test will pass without really
+ // testing anything, which is OK.
+ time.Sleep(time.Millisecond)
+
+ ln.Close()
+
+ ln2, err := Listen("tcp", addr.String())
+ if err != nil {
+ t.Fatal(err)
+ }
+ ln2.Close()
+}
+
+func TestListenConfigControl(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+
+ t.Run("StreamListen", func(t *testing.T) {
+ for _, network := range []string{"tcp", "tcp4", "tcp6", "unix", "unixpacket"} {
+ if !testableNetwork(network) {
+ continue
+ }
+ ln := newLocalListener(t, network, &ListenConfig{Control: controlOnConnSetup})
+ ln.Close()
+ }
+ })
+ t.Run("PacketListen", func(t *testing.T) {
+ for _, network := range []string{"udp", "udp4", "udp6", "unixgram"} {
+ if !testableNetwork(network) {
+ continue
+ }
+ c := newLocalPacketListener(t, network, &ListenConfig{Control: controlOnConnSetup})
+ c.Close()
+ }
+ })
+}
diff --git a/go/src/net/lookup.go b/go/src/net/lookup.go
new file mode 100644
index 0000000000000000000000000000000000000000..d4be8eaa0e10c3786fd99a4358daa0b71f94c504
--- /dev/null
+++ b/go/src/net/lookup.go
@@ -0,0 +1,917 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "context"
+ "errors"
+ "internal/nettrace"
+ "internal/singleflight"
+ "internal/stringslite"
+ "net/netip"
+ "sync"
+
+ "golang.org/x/net/dns/dnsmessage"
+)
+
+// protocols contains minimal mappings between internet protocol
+// names and numbers for platforms that don't have a complete list of
+// protocol numbers.
+//
+// See https://www.iana.org/assignments/protocol-numbers
+//
+// On Unix, this map is augmented by readProtocols via lookupProtocol.
+var protocols = map[string]int{
+ "icmp": 1,
+ "igmp": 2,
+ "tcp": 6,
+ "udp": 17,
+ "ipv6-icmp": 58,
+}
+
+// services contains minimal mappings between services names and port
+// numbers for platforms that don't have a complete list of port numbers.
+//
+// See https://www.iana.org/assignments/service-names-port-numbers
+//
+// On Unix, this map is augmented by readServices via goLookupPort.
+var services = map[string]map[string]int{
+ "udp": {
+ "domain": 53,
+ },
+ "tcp": {
+ "ftp": 21,
+ "ftps": 990,
+ "gopher": 70, // ʕ◔ϖ◔ʔ
+ "http": 80,
+ "https": 443,
+ "imap2": 143,
+ "imap3": 220,
+ "imaps": 993,
+ "pop3": 110,
+ "pop3s": 995,
+ "smtp": 25,
+ "submissions": 465,
+ "ssh": 22,
+ "telnet": 23,
+ },
+}
+
+// dnsWaitGroup can be used by tests to wait for all DNS goroutines to
+// complete. This avoids races on the test hooks.
+var dnsWaitGroup sync.WaitGroup
+
+const maxProtoLength = len("RSVP-E2E-IGNORE") + 10 // with room to grow
+
+func lookupProtocolMap(name string) (int, error) {
+ var lowerProtocol [maxProtoLength]byte
+ n := copy(lowerProtocol[:], name)
+ lowerASCIIBytes(lowerProtocol[:n])
+ proto, found := protocols[string(lowerProtocol[:n])]
+ if !found || n != len(name) {
+ return 0, &AddrError{Err: "unknown IP protocol specified", Addr: name}
+ }
+ return proto, nil
+}
+
+// maxPortBufSize is the longest reasonable name of a service
+// (non-numeric port).
+// Currently the longest known IANA-unregistered name is
+// "mobility-header", so we use that length, plus some slop in case
+// something longer is added in the future.
+const maxPortBufSize = len("mobility-header") + 10
+
+func lookupPortMap(network, service string) (port int, error error) {
+ switch network {
+ case "ip": // no hints
+ if p, err := lookupPortMapWithNetwork("tcp", "ip", service); err == nil {
+ return p, nil
+ }
+ return lookupPortMapWithNetwork("udp", "ip", service)
+ case "tcp", "tcp4", "tcp6":
+ return lookupPortMapWithNetwork("tcp", "tcp", service)
+ case "udp", "udp4", "udp6":
+ return lookupPortMapWithNetwork("udp", "udp", service)
+ }
+ return 0, &DNSError{Err: "unknown network", Name: network + "/" + service}
+}
+
+func lookupPortMapWithNetwork(network, errNetwork, service string) (port int, error error) {
+ if m, ok := services[network]; ok {
+ var lowerService [maxPortBufSize]byte
+ n := copy(lowerService[:], service)
+ lowerASCIIBytes(lowerService[:n])
+ if port, ok := m[string(lowerService[:n])]; ok && n == len(service) {
+ return port, nil
+ }
+ return 0, newDNSError(errUnknownPort, errNetwork+"/"+service, "")
+ }
+ return 0, &DNSError{Err: "unknown network", Name: errNetwork + "/" + service}
+}
+
+// ipVersion returns the provided network's IP version: '4', '6' or 0
+// if network does not end in a '4' or '6' byte.
+func ipVersion(network string) byte {
+ if network == "" {
+ return 0
+ }
+ n := network[len(network)-1]
+ if n != '4' && n != '6' {
+ n = 0
+ }
+ return n
+}
+
+// DefaultResolver is the resolver used by the package-level Lookup
+// functions and by Dialers without a specified Resolver.
+var DefaultResolver = &Resolver{}
+
+// A Resolver looks up names and numbers.
+//
+// A nil *Resolver is equivalent to a zero Resolver.
+type Resolver struct {
+ // PreferGo controls whether Go's built-in DNS resolver is preferred
+ // on platforms where it's available. It is equivalent to setting
+ // GODEBUG=netdns=go, but scoped to just this resolver.
+ PreferGo bool
+
+ // StrictErrors controls the behavior of temporary errors
+ // (including timeout, socket errors, and SERVFAIL) when using
+ // Go's built-in resolver. For a query composed of multiple
+ // sub-queries (such as an A+AAAA address lookup, or walking the
+ // DNS search list), this option causes such errors to abort the
+ // whole query instead of returning a partial result. This is
+ // not enabled by default because it may affect compatibility
+ // with resolvers that process AAAA queries incorrectly.
+ StrictErrors bool
+
+ // Dial optionally specifies an alternate dialer for use by
+ // Go's built-in DNS resolver to make TCP and UDP connections
+ // to DNS services. The host in the address parameter will
+ // always be a literal IP address and not a host name, and the
+ // port in the address parameter will be a literal port number
+ // and not a service name.
+ // If the Conn returned is also a PacketConn, sent and received DNS
+ // messages must adhere to RFC 1035 section 4.2.1, "UDP usage".
+ // Otherwise, DNS messages transmitted over Conn must adhere
+ // to RFC 7766 section 5, "Transport Protocol Selection".
+ // If nil, the default dialer is used.
+ Dial func(ctx context.Context, network, address string) (Conn, error)
+
+ // lookupGroup merges LookupIPAddr calls together for lookups for the same
+ // host. The lookupGroup key is the LookupIPAddr.host argument.
+ // The return values are ([]IPAddr, error).
+ lookupGroup singleflight.Group
+
+ // TODO(bradfitz): optional interface impl override hook
+ // TODO(bradfitz): Timeout time.Duration?
+}
+
+func (r *Resolver) preferGo() bool { return r != nil && r.PreferGo }
+func (r *Resolver) strictErrors() bool { return r != nil && r.StrictErrors }
+
+func (r *Resolver) getLookupGroup() *singleflight.Group {
+ if r == nil {
+ return &DefaultResolver.lookupGroup
+ }
+ return &r.lookupGroup
+}
+
+// LookupHost looks up the given host using the local resolver.
+// It returns a slice of that host's addresses.
+//
+// LookupHost uses [context.Background] internally; to specify the context, use
+// [Resolver.LookupHost].
+func LookupHost(host string) (addrs []string, err error) {
+ return DefaultResolver.LookupHost(context.Background(), host)
+}
+
+// LookupHost looks up the given host using the local resolver.
+// It returns a slice of that host's addresses.
+func (r *Resolver) LookupHost(ctx context.Context, host string) (addrs []string, err error) {
+ // Make sure that no matter what we do later, host=="" is rejected.
+ if host == "" {
+ return nil, newDNSError(errNoSuchHost, host, "")
+ }
+ if _, err := netip.ParseAddr(host); err == nil {
+ return []string{host}, nil
+ }
+ return r.lookupHost(ctx, host)
+}
+
+// LookupIP looks up host using the local resolver.
+// It returns a slice of that host's IPv4 and IPv6 addresses.
+func LookupIP(host string) ([]IP, error) {
+ addrs, err := DefaultResolver.LookupIPAddr(context.Background(), host)
+ if err != nil {
+ return nil, err
+ }
+ ips := make([]IP, len(addrs))
+ for i, ia := range addrs {
+ ips[i] = ia.IP
+ }
+ return ips, nil
+}
+
+// LookupIPAddr looks up host using the local resolver.
+// It returns a slice of that host's IPv4 and IPv6 addresses.
+func (r *Resolver) LookupIPAddr(ctx context.Context, host string) ([]IPAddr, error) {
+ return r.lookupIPAddr(ctx, "ip", host)
+}
+
+// LookupIP looks up host for the given network using the local resolver.
+// It returns a slice of that host's IP addresses of the type specified by
+// network.
+// network must be one of "ip", "ip4" or "ip6".
+func (r *Resolver) LookupIP(ctx context.Context, network, host string) ([]IP, error) {
+ afnet, _, err := parseNetwork(ctx, network, false)
+ if err != nil {
+ return nil, err
+ }
+ switch afnet {
+ case "ip", "ip4", "ip6":
+ default:
+ return nil, UnknownNetworkError(network)
+ }
+
+ if host == "" {
+ return nil, newDNSError(errNoSuchHost, host, "")
+ }
+ addrs, err := r.internetAddrList(ctx, afnet, host)
+ if err != nil {
+ return nil, err
+ }
+
+ ips := make([]IP, 0, len(addrs))
+ for _, addr := range addrs {
+ ips = append(ips, addr.(*IPAddr).IP)
+ }
+ return ips, nil
+}
+
+// LookupNetIP looks up host using the local resolver.
+// It returns a slice of that host's IP addresses of the type specified by
+// network.
+// The network must be one of "ip", "ip4" or "ip6".
+func (r *Resolver) LookupNetIP(ctx context.Context, network, host string) ([]netip.Addr, error) {
+ // TODO(bradfitz): make this efficient, making the internal net package
+ // type throughout be netip.Addr and only converting to the net.IP slice
+ // version at the edge. But for now (2021-10-20), this is a wrapper around
+ // the old way.
+ ips, err := r.LookupIP(ctx, network, host)
+ if err != nil {
+ return nil, err
+ }
+ ret := make([]netip.Addr, 0, len(ips))
+ for _, ip := range ips {
+ if a, ok := netip.AddrFromSlice(ip); ok {
+ ret = append(ret, a)
+ }
+ }
+ return ret, nil
+}
+
+// onlyValuesCtx is a context that uses an underlying context
+// for value lookup if the underlying context hasn't yet expired.
+type onlyValuesCtx struct {
+ context.Context
+ lookupValues context.Context
+}
+
+var _ context.Context = (*onlyValuesCtx)(nil)
+
+// Value performs a lookup if the original context hasn't expired.
+func (ovc *onlyValuesCtx) Value(key any) any {
+ select {
+ case <-ovc.lookupValues.Done():
+ return nil
+ default:
+ return ovc.lookupValues.Value(key)
+ }
+}
+
+// withUnexpiredValuesPreserved returns a context.Context that only uses lookupCtx
+// for its values, otherwise it is never canceled and has no deadline.
+// If the lookup context expires, any looked up values will return nil.
+// See Issue 28600.
+func withUnexpiredValuesPreserved(lookupCtx context.Context) context.Context {
+ return &onlyValuesCtx{Context: context.Background(), lookupValues: lookupCtx}
+}
+
+// lookupIPAddr looks up host using the local resolver and particular network.
+// It returns a slice of that host's IPv4 and IPv6 addresses.
+func (r *Resolver) lookupIPAddr(ctx context.Context, network, host string) ([]IPAddr, error) {
+ // Make sure that no matter what we do later, host=="" is rejected.
+ if host == "" {
+ return nil, newDNSError(errNoSuchHost, host, "")
+ }
+ if ip, err := netip.ParseAddr(host); err == nil {
+ return []IPAddr{{IP: IP(ip.AsSlice()).To16(), Zone: ip.Zone()}}, nil
+ }
+ trace, _ := ctx.Value(nettrace.TraceKey{}).(*nettrace.Trace)
+ if trace != nil && trace.DNSStart != nil {
+ trace.DNSStart(host)
+ }
+ // The underlying resolver func is lookupIP by default but it
+ // can be overridden by tests. This is needed by net/http, so it
+ // uses a context key instead of unexported variables.
+ resolverFunc := r.lookupIP
+ if alt, _ := ctx.Value(nettrace.LookupIPAltResolverKey{}).(func(context.Context, string, string) ([]IPAddr, error)); alt != nil {
+ resolverFunc = alt
+ }
+
+ // We don't want a cancellation of ctx to affect the
+ // lookupGroup operation. Otherwise if our context gets
+ // canceled it might cause an error to be returned to a lookup
+ // using a completely different context. However we need to preserve
+ // only the values in context. See Issue 28600.
+ lookupGroupCtx, lookupGroupCancel := context.WithCancel(withUnexpiredValuesPreserved(ctx))
+
+ lookupKey := network + "\000" + host
+ dnsWaitGroup.Add(1)
+ ch := r.getLookupGroup().DoChan(lookupKey, func() (any, error) {
+ return testHookLookupIP(lookupGroupCtx, resolverFunc, network, host)
+ })
+
+ dnsWaitGroupDone := func(ch <-chan singleflight.Result, cancelFn context.CancelFunc) {
+ <-ch
+ dnsWaitGroup.Done()
+ cancelFn()
+ }
+ select {
+ case <-ctx.Done():
+ // Our context was canceled. If we are the only
+ // goroutine looking up this key, then drop the key
+ // from the lookupGroup and cancel the lookup.
+ // If there are other goroutines looking up this key,
+ // let the lookup continue uncanceled, and let later
+ // lookups with the same key share the result.
+ // See issues 8602, 20703, 22724.
+ if r.getLookupGroup().ForgetUnshared(lookupKey) {
+ lookupGroupCancel()
+ go dnsWaitGroupDone(ch, func() {})
+ } else {
+ go dnsWaitGroupDone(ch, lookupGroupCancel)
+ }
+ err := newDNSError(mapErr(ctx.Err()), host, "")
+ if trace != nil && trace.DNSDone != nil {
+ trace.DNSDone(nil, false, err)
+ }
+ return nil, err
+ case r := <-ch:
+ dnsWaitGroup.Done()
+ lookupGroupCancel()
+ err := r.Err
+ if err != nil {
+ if _, ok := err.(*DNSError); !ok {
+ err = newDNSError(mapErr(err), host, "")
+ }
+ }
+ if trace != nil && trace.DNSDone != nil {
+ addrs, _ := r.Val.([]IPAddr)
+ trace.DNSDone(ipAddrsEface(addrs), r.Shared, err)
+ }
+ return lookupIPReturn(r.Val, err, r.Shared)
+ }
+}
+
+// lookupIPReturn turns the return values from singleflight.Do into
+// the return values from LookupIP.
+func lookupIPReturn(addrsi any, err error, shared bool) ([]IPAddr, error) {
+ if err != nil {
+ return nil, err
+ }
+ addrs := addrsi.([]IPAddr)
+ if shared {
+ clone := make([]IPAddr, len(addrs))
+ copy(clone, addrs)
+ addrs = clone
+ }
+ return addrs, nil
+}
+
+// ipAddrsEface returns an empty interface slice of addrs.
+func ipAddrsEface(addrs []IPAddr) []any {
+ s := make([]any, len(addrs))
+ for i, v := range addrs {
+ s[i] = v
+ }
+ return s
+}
+
+// LookupPort looks up the port for the given network and service.
+//
+// LookupPort uses [context.Background] internally; to specify the context, use
+// [Resolver.LookupPort].
+func LookupPort(network, service string) (port int, err error) {
+ return DefaultResolver.LookupPort(context.Background(), network, service)
+}
+
+// LookupPort looks up the port for the given network and service.
+//
+// The network must be one of "tcp", "tcp4", "tcp6", "udp", "udp4", "udp6" or "ip".
+func (r *Resolver) LookupPort(ctx context.Context, network, service string) (port int, err error) {
+ port, needsLookup := parsePort(service)
+ if needsLookup {
+ switch network {
+ case "tcp", "tcp4", "tcp6", "udp", "udp4", "udp6", "ip":
+ case "": // a hint wildcard for Go 1.0 undocumented behavior
+ network = "ip"
+ default:
+ return 0, &AddrError{Err: "unknown network", Addr: network}
+ }
+ port, err = r.lookupPort(ctx, network, service)
+ if err != nil {
+ return 0, err
+ }
+ }
+ if 0 > port || port > 65535 {
+ return 0, &AddrError{Err: "invalid port", Addr: service}
+ }
+ return port, nil
+}
+
+// LookupCNAME returns the canonical name for the given host.
+// Callers that do not care about the canonical name can call
+// [LookupHost] or [LookupIP] directly; both take care of resolving
+// the canonical name as part of the lookup.
+//
+// A canonical name is the final name after following zero
+// or more CNAME records.
+// LookupCNAME does not return an error if host does not
+// contain DNS "CNAME" records, as long as host resolves to
+// address records.
+//
+// The returned canonical name is validated to be a properly
+// formatted presentation-format domain name.
+//
+// LookupCNAME uses [context.Background] internally; to specify the context, use
+// [Resolver.LookupCNAME].
+func LookupCNAME(host string) (cname string, err error) {
+ return DefaultResolver.LookupCNAME(context.Background(), host)
+}
+
+// LookupCNAME returns the canonical name for the given host.
+// Callers that do not care about the canonical name can call
+// [LookupHost] or [LookupIP] directly; both take care of resolving
+// the canonical name as part of the lookup.
+//
+// A canonical name is the final name after following zero
+// or more CNAME records.
+// LookupCNAME does not return an error if host does not
+// contain DNS "CNAME" records, as long as host resolves to
+// address records.
+//
+// The returned canonical name is validated to be a properly
+// formatted presentation-format domain name.
+func (r *Resolver) LookupCNAME(ctx context.Context, host string) (string, error) {
+ cname, err := r.lookupCNAME(ctx, host)
+ if err != nil {
+ return "", err
+ }
+ if !isDomainName(cname) {
+ return "", &DNSError{Err: errMalformedDNSRecordsDetail, Name: host}
+ }
+ return cname, nil
+}
+
+// LookupSRV tries to resolve an [SRV] query of the given service,
+// protocol, and domain name. The proto is "tcp" or "udp".
+// The returned records are sorted by priority and randomized
+// by weight within a priority.
+//
+// LookupSRV constructs the DNS name to look up following RFC 2782.
+// That is, it looks up _service._proto.name. To accommodate services
+// publishing SRV records under non-standard names, if both service
+// and proto are empty strings, LookupSRV looks up name directly.
+//
+// The returned service names are validated to be properly
+// formatted presentation-format domain names. If the response contains
+// invalid names, those records are filtered out and an error
+// will be returned alongside the remaining results, if any.
+func LookupSRV(service, proto, name string) (cname string, addrs []*SRV, err error) {
+ return DefaultResolver.LookupSRV(context.Background(), service, proto, name)
+}
+
+// LookupSRV tries to resolve an [SRV] query of the given service,
+// protocol, and domain name. The proto is "tcp" or "udp".
+// The returned records are sorted by priority and randomized
+// by weight within a priority.
+//
+// LookupSRV constructs the DNS name to look up following RFC 2782.
+// That is, it looks up _service._proto.name. To accommodate services
+// publishing SRV records under non-standard names, if both service
+// and proto are empty strings, LookupSRV looks up name directly.
+//
+// The returned service names are validated to be properly
+// formatted presentation-format domain names. If the response contains
+// invalid names, those records are filtered out and an error
+// will be returned alongside the remaining results, if any.
+func (r *Resolver) LookupSRV(ctx context.Context, service, proto, name string) (string, []*SRV, error) {
+ cname, addrs, err := r.lookupSRV(ctx, service, proto, name)
+ if err != nil {
+ return "", nil, err
+ }
+ if cname != "" && !isDomainName(cname) {
+ return "", nil, &DNSError{Err: "SRV header name is invalid", Name: name}
+ }
+ filteredAddrs := make([]*SRV, 0, len(addrs))
+ for _, addr := range addrs {
+ if addr == nil {
+ continue
+ }
+ if !isDomainName(addr.Target) {
+ continue
+ }
+ filteredAddrs = append(filteredAddrs, addr)
+ }
+ if len(addrs) != len(filteredAddrs) {
+ return cname, filteredAddrs, &DNSError{Err: errMalformedDNSRecordsDetail, Name: name}
+ }
+ return cname, filteredAddrs, nil
+}
+
+// LookupMX returns the DNS MX records for the given domain name sorted by preference.
+//
+// The returned mail server names are validated to be properly
+// formatted presentation-format domain names, or numeric IP addresses.
+// If the response contains invalid names, those records are filtered out
+// and an error will be returned alongside the remaining results, if any.
+//
+// LookupMX uses [context.Background] internally; to specify the context, use
+// [Resolver.LookupMX].
+func LookupMX(name string) ([]*MX, error) {
+ return DefaultResolver.LookupMX(context.Background(), name)
+}
+
+// LookupMX returns the DNS MX records for the given domain name sorted by preference.
+//
+// The returned mail server names are validated to be properly
+// formatted presentation-format domain names, or numeric IP addresses.
+// If the response contains invalid names, those records are filtered out
+// and an error will be returned alongside the remaining results, if any.
+func (r *Resolver) LookupMX(ctx context.Context, name string) ([]*MX, error) {
+ records, err := r.lookupMX(ctx, name)
+ if err != nil {
+ return nil, err
+ }
+ filteredMX := make([]*MX, 0, len(records))
+ for _, mx := range records {
+ if mx == nil {
+ continue
+ }
+ if !isDomainName(mx.Host) {
+ // Check for IP address. In practice we observe
+ // these with a trailing dot, so strip that.
+ ip, err := netip.ParseAddr(stringslite.TrimSuffix(mx.Host, "."))
+ if err != nil || ip.Zone() != "" {
+ continue
+ }
+ }
+ filteredMX = append(filteredMX, mx)
+ }
+ if len(records) != len(filteredMX) {
+ return filteredMX, &DNSError{Err: errMalformedDNSRecordsDetail, Name: name}
+ }
+ return filteredMX, nil
+}
+
+// LookupNS returns the DNS NS records for the given domain name.
+//
+// The returned name server names are validated to be properly
+// formatted presentation-format domain names. If the response contains
+// invalid names, those records are filtered out and an error
+// will be returned alongside the remaining results, if any.
+//
+// LookupNS uses [context.Background] internally; to specify the context, use
+// [Resolver.LookupNS].
+func LookupNS(name string) ([]*NS, error) {
+ return DefaultResolver.LookupNS(context.Background(), name)
+}
+
+// LookupNS returns the DNS NS records for the given domain name.
+//
+// The returned name server names are validated to be properly
+// formatted presentation-format domain names. If the response contains
+// invalid names, those records are filtered out and an error
+// will be returned alongside the remaining results, if any.
+func (r *Resolver) LookupNS(ctx context.Context, name string) ([]*NS, error) {
+ records, err := r.lookupNS(ctx, name)
+ if err != nil {
+ return nil, err
+ }
+ filteredNS := make([]*NS, 0, len(records))
+ for _, ns := range records {
+ if ns == nil {
+ continue
+ }
+ if !isDomainName(ns.Host) {
+ continue
+ }
+ filteredNS = append(filteredNS, ns)
+ }
+ if len(records) != len(filteredNS) {
+ return filteredNS, &DNSError{Err: errMalformedDNSRecordsDetail, Name: name}
+ }
+ return filteredNS, nil
+}
+
+// LookupTXT returns the DNS TXT records for the given domain name.
+//
+// If a DNS TXT record holds multiple strings, they are concatenated as a
+// single string.
+//
+// LookupTXT uses [context.Background] internally; to specify the context, use
+// [Resolver.LookupTXT].
+func LookupTXT(name string) ([]string, error) {
+ return DefaultResolver.lookupTXT(context.Background(), name)
+}
+
+// LookupTXT returns the DNS TXT records for the given domain name.
+//
+// If a DNS TXT record holds multiple strings, they are concatenated as a
+// single string.
+func (r *Resolver) LookupTXT(ctx context.Context, name string) ([]string, error) {
+ return r.lookupTXT(ctx, name)
+}
+
+// LookupAddr performs a reverse lookup for the given address, returning a list
+// of names mapping to that address.
+//
+// The returned names are validated to be properly formatted presentation-format
+// domain names. If the response contains invalid names, those records are filtered
+// out and an error will be returned alongside the remaining results, if any.
+//
+// When using the host C library resolver, at most one result will be
+// returned. To bypass the host resolver, use a custom [Resolver].
+//
+// LookupAddr uses [context.Background] internally; to specify the context, use
+// [Resolver.LookupAddr].
+func LookupAddr(addr string) (names []string, err error) {
+ return DefaultResolver.LookupAddr(context.Background(), addr)
+}
+
+// LookupAddr performs a reverse lookup for the given address, returning a list
+// of names mapping to that address.
+//
+// The returned names are validated to be properly formatted presentation-format
+// domain names. If the response contains invalid names, those records are filtered
+// out and an error will be returned alongside the remaining results, if any.
+func (r *Resolver) LookupAddr(ctx context.Context, addr string) ([]string, error) {
+ names, err := r.lookupAddr(ctx, addr)
+ if err != nil {
+ return nil, err
+ }
+ filteredNames := make([]string, 0, len(names))
+ for _, name := range names {
+ if isDomainName(name) {
+ filteredNames = append(filteredNames, name)
+ }
+ }
+ if len(names) != len(filteredNames) {
+ return filteredNames, &DNSError{Err: errMalformedDNSRecordsDetail, Name: addr}
+ }
+ return filteredNames, nil
+}
+
+// errMalformedDNSRecordsDetail is the DNSError detail which is returned when a Resolver.Lookup...
+// method receives DNS records which contain invalid DNS names. This may be returned alongside
+// results which have had the malformed records filtered out.
+var errMalformedDNSRecordsDetail = "DNS response contained records which contain invalid names"
+
+// dial makes a new connection to the provided server (which must be
+// an IP address) with the provided network type, using either r.Dial
+// (if both r and r.Dial are non-nil) or else Dialer.DialContext.
+func (r *Resolver) dial(ctx context.Context, network, server string) (Conn, error) {
+ // Calling Dial here is scary -- we have to be sure not to
+ // dial a name that will require a DNS lookup, or Dial will
+ // call back here to translate it. The DNS config parser has
+ // already checked that all the cfg.servers are IP
+ // addresses, which Dial will use without a DNS lookup.
+ var c Conn
+ var err error
+ if r != nil && r.Dial != nil {
+ c, err = r.Dial(ctx, network, server)
+ } else {
+ var d Dialer
+ c, err = d.DialContext(ctx, network, server)
+ }
+ if err != nil {
+ return nil, mapErr(err)
+ }
+ return c, nil
+}
+
+// goLookupSRV returns the SRV records for a target name, built either
+// from its component service ("sip"), protocol ("tcp"), and name
+// ("example.com."), or from name directly (if service and proto are
+// both empty).
+//
+// In either case, the returned target name ("_sip._tcp.example.com.")
+// is also returned on success.
+//
+// The records are sorted by weight.
+func (r *Resolver) goLookupSRV(ctx context.Context, service, proto, name string) (target string, srvs []*SRV, err error) {
+ if service == "" && proto == "" {
+ target = name
+ } else {
+ target = "_" + service + "._" + proto + "." + name
+ }
+ p, server, err := r.lookup(ctx, target, dnsmessage.TypeSRV, nil)
+ if err != nil {
+ return "", nil, err
+ }
+ var cname dnsmessage.Name
+ for {
+ h, err := p.AnswerHeader()
+ if err == dnsmessage.ErrSectionDone {
+ break
+ }
+ if err != nil {
+ return "", nil, &DNSError{
+ Err: "cannot unmarshal DNS message",
+ Name: name,
+ Server: server,
+ }
+ }
+ if h.Type != dnsmessage.TypeSRV {
+ if err := p.SkipAnswer(); err != nil {
+ return "", nil, &DNSError{
+ Err: "cannot unmarshal DNS message",
+ Name: name,
+ Server: server,
+ }
+ }
+ continue
+ }
+ if cname.Length == 0 && h.Name.Length != 0 {
+ cname = h.Name
+ }
+ srv, err := p.SRVResource()
+ if err != nil {
+ return "", nil, &DNSError{
+ Err: "cannot unmarshal DNS message",
+ Name: name,
+ Server: server,
+ }
+ }
+ srvs = append(srvs, &SRV{Target: srv.Target.String(), Port: srv.Port, Priority: srv.Priority, Weight: srv.Weight})
+ }
+ byPriorityWeight(srvs).sort()
+ return cname.String(), srvs, nil
+}
+
+// goLookupMX returns the MX records for name.
+func (r *Resolver) goLookupMX(ctx context.Context, name string) ([]*MX, error) {
+ p, server, err := r.lookup(ctx, name, dnsmessage.TypeMX, nil)
+ if err != nil {
+ return nil, err
+ }
+ var mxs []*MX
+ for {
+ h, err := p.AnswerHeader()
+ if err == dnsmessage.ErrSectionDone {
+ break
+ }
+ if err != nil {
+ return nil, &DNSError{
+ Err: "cannot unmarshal DNS message",
+ Name: name,
+ Server: server,
+ }
+ }
+ if h.Type != dnsmessage.TypeMX {
+ if err := p.SkipAnswer(); err != nil {
+ return nil, &DNSError{
+ Err: "cannot unmarshal DNS message",
+ Name: name,
+ Server: server,
+ }
+ }
+ continue
+ }
+ mx, err := p.MXResource()
+ if err != nil {
+ return nil, &DNSError{
+ Err: "cannot unmarshal DNS message",
+ Name: name,
+ Server: server,
+ }
+ }
+ mxs = append(mxs, &MX{Host: mx.MX.String(), Pref: mx.Pref})
+
+ }
+ byPref(mxs).sort()
+ return mxs, nil
+}
+
+// goLookupNS returns the NS records for name.
+func (r *Resolver) goLookupNS(ctx context.Context, name string) ([]*NS, error) {
+ p, server, err := r.lookup(ctx, name, dnsmessage.TypeNS, nil)
+ if err != nil {
+ return nil, err
+ }
+ var nss []*NS
+ for {
+ h, err := p.AnswerHeader()
+ if err == dnsmessage.ErrSectionDone {
+ break
+ }
+ if err != nil {
+ return nil, &DNSError{
+ Err: "cannot unmarshal DNS message",
+ Name: name,
+ Server: server,
+ }
+ }
+ if h.Type != dnsmessage.TypeNS {
+ if err := p.SkipAnswer(); err != nil {
+ return nil, &DNSError{
+ Err: "cannot unmarshal DNS message",
+ Name: name,
+ Server: server,
+ }
+ }
+ continue
+ }
+ ns, err := p.NSResource()
+ if err != nil {
+ return nil, &DNSError{
+ Err: "cannot unmarshal DNS message",
+ Name: name,
+ Server: server,
+ }
+ }
+ nss = append(nss, &NS{Host: ns.NS.String()})
+ }
+ return nss, nil
+}
+
+// goLookupTXT returns the TXT records from name.
+func (r *Resolver) goLookupTXT(ctx context.Context, name string) ([]string, error) {
+ p, server, err := r.lookup(ctx, name, dnsmessage.TypeTXT, nil)
+ if err != nil {
+ return nil, err
+ }
+ var txts []string
+ for {
+ h, err := p.AnswerHeader()
+ if err == dnsmessage.ErrSectionDone {
+ break
+ }
+ if err != nil {
+ return nil, &DNSError{
+ Err: "cannot unmarshal DNS message",
+ Name: name,
+ Server: server,
+ }
+ }
+ if h.Type != dnsmessage.TypeTXT {
+ if err := p.SkipAnswer(); err != nil {
+ return nil, &DNSError{
+ Err: "cannot unmarshal DNS message",
+ Name: name,
+ Server: server,
+ }
+ }
+ continue
+ }
+ txt, err := p.TXTResource()
+ if err != nil {
+ return nil, &DNSError{
+ Err: "cannot unmarshal DNS message",
+ Name: name,
+ Server: server,
+ }
+ }
+ // Multiple strings in one TXT record need to be
+ // concatenated without separator to be consistent
+ // with previous Go resolver.
+ n := 0
+ for _, s := range txt.TXT {
+ n += len(s)
+ }
+ txtJoin := make([]byte, 0, n)
+ for _, s := range txt.TXT {
+ txtJoin = append(txtJoin, s...)
+ }
+ if len(txts) == 0 {
+ txts = make([]string, 0, 1)
+ }
+ txts = append(txts, string(txtJoin))
+ }
+ return txts, nil
+}
+
+func parseCNAMEFromResources(resources []dnsmessage.Resource) (string, error) {
+ if len(resources) == 0 {
+ return "", errors.New("no CNAME record received")
+ }
+ c, ok := resources[0].Body.(*dnsmessage.CNAMEResource)
+ if !ok {
+ return "", errors.New("could not parse CNAME record")
+ }
+ return c.CNAME.String(), nil
+}
diff --git a/go/src/net/lookup_plan9.go b/go/src/net/lookup_plan9.go
new file mode 100644
index 0000000000000000000000000000000000000000..836beb3b17158b06e454a8848e4f842d0a7c28a2
--- /dev/null
+++ b/go/src/net/lookup_plan9.go
@@ -0,0 +1,384 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "context"
+ "errors"
+ "internal/bytealg"
+ "internal/strconv"
+ "internal/stringslite"
+ "io"
+ "os"
+)
+
+// cgoAvailable set to true to indicate that the cgo resolver
+// is available on Plan 9. Note that on Plan 9 the cgo resolver
+// does not actually use cgo.
+const cgoAvailable = true
+
+func query(ctx context.Context, filename, query string, bufSize int) (addrs []string, err error) {
+ queryAddrs := func() (addrs []string, err error) {
+ file, err := os.OpenFile(filename, os.O_RDWR, 0)
+ if err != nil {
+ return nil, err
+ }
+ defer file.Close()
+
+ _, err = file.Seek(0, io.SeekStart)
+ if err != nil {
+ return nil, err
+ }
+ _, err = file.WriteString(query)
+ if err != nil {
+ return nil, err
+ }
+ _, err = file.Seek(0, io.SeekStart)
+ if err != nil {
+ return nil, err
+ }
+ buf := make([]byte, bufSize)
+ for {
+ n, _ := file.Read(buf)
+ if n <= 0 {
+ break
+ }
+ addrs = append(addrs, string(buf[:n]))
+ }
+ return addrs, nil
+ }
+
+ type ret struct {
+ addrs []string
+ err error
+ }
+
+ ch := make(chan ret, 1)
+ go func() {
+ addrs, err := queryAddrs()
+ ch <- ret{addrs: addrs, err: err}
+ }()
+
+ select {
+ case r := <-ch:
+ return r.addrs, r.err
+ case <-ctx.Done():
+ return nil, mapErr(ctx.Err())
+ }
+}
+
+func queryCS(ctx context.Context, net, host, service string) (res []string, err error) {
+ switch net {
+ case "tcp4", "tcp6":
+ net = "tcp"
+ case "udp4", "udp6":
+ net = "udp"
+ }
+ if host == "" {
+ host = "*"
+ }
+ return query(ctx, netdir+"/cs", net+"!"+host+"!"+service, 128)
+}
+
+func queryCS1(ctx context.Context, net string, ip IP, port int) (clone, dest string, err error) {
+ ips := "*"
+ if len(ip) != 0 && !ip.IsUnspecified() {
+ ips = ip.String()
+ }
+ lines, err := queryCS(ctx, net, ips, strconv.Itoa(port))
+ if err != nil {
+ return
+ }
+ f := getFields(lines[0])
+ if len(f) < 2 {
+ return "", "", errors.New("bad response from ndb/cs")
+ }
+ clone, dest = f[0], f[1]
+ return
+}
+
+func queryDNS(ctx context.Context, addr string, typ string) (res []string, err error) {
+ return query(ctx, netdir+"/dns", addr+" "+typ, 1024)
+}
+
+func handlePlan9DNSError(err error, name string) error {
+ if stringslite.HasSuffix(err.Error(), "dns: name does not exist") ||
+ stringslite.HasSuffix(err.Error(), "dns: resource does not exist; negrcode 0") ||
+ stringslite.HasSuffix(err.Error(), "dns: resource does not exist; negrcode") ||
+ stringslite.HasSuffix(err.Error(), "dns failure") {
+ err = errNoSuchHost
+ }
+ return newDNSError(err, name, "")
+}
+
+// toLower returns a lower-case version of in. Restricting us to
+// ASCII is sufficient to handle the IP protocol names and allow
+// us to not depend on the strings and unicode packages.
+func toLower(in string) string {
+ for _, c := range in {
+ if 'A' <= c && c <= 'Z' {
+ // Has upper case; need to fix.
+ out := []byte(in)
+ for i := 0; i < len(in); i++ {
+ c := in[i]
+ if 'A' <= c && c <= 'Z' {
+ c += 'a' - 'A'
+ }
+ out[i] = c
+ }
+ return string(out)
+ }
+ }
+ return in
+}
+
+// lookupProtocol looks up IP protocol name and returns
+// the corresponding protocol number.
+func lookupProtocol(ctx context.Context, name string) (proto int, err error) {
+ lines, err := query(ctx, netdir+"/cs", "!protocol="+toLower(name), 128)
+ if err != nil {
+ return 0, newDNSError(err, name, "")
+ }
+ if len(lines) == 0 {
+ return 0, UnknownNetworkError(name)
+ }
+ f := getFields(lines[0])
+ if len(f) < 2 {
+ return 0, UnknownNetworkError(name)
+ }
+ s := f[1]
+ if n, _, ok := dtoi(s[bytealg.IndexByteString(s, '=')+1:]); ok {
+ return n, nil
+ }
+ return 0, UnknownNetworkError(name)
+}
+
+func (*Resolver) lookupHost(ctx context.Context, host string) (addrs []string, err error) {
+ // Use netdir/cs instead of netdir/dns because cs knows about
+ // host names in local network (e.g. from /lib/ndb/local)
+ lines, err := queryCS(ctx, "net", host, "1")
+ if err != nil {
+ return nil, handlePlan9DNSError(err, host)
+ }
+loop:
+ for _, line := range lines {
+ f := getFields(line)
+ if len(f) < 2 {
+ continue
+ }
+ addr := f[1]
+ if i := bytealg.IndexByteString(addr, '!'); i >= 0 {
+ addr = addr[:i] // remove port
+ }
+ if ParseIP(addr) == nil {
+ continue
+ }
+ // only return unique addresses
+ for _, a := range addrs {
+ if a == addr {
+ continue loop
+ }
+ }
+ addrs = append(addrs, addr)
+ }
+ return
+}
+
+func (r *Resolver) lookupIP(ctx context.Context, network, host string) (addrs []IPAddr, err error) {
+ if order, conf := systemConf().hostLookupOrder(r, host); order != hostLookupCgo {
+ return r.goLookupIP(ctx, network, host, order, conf)
+ }
+
+ lits, err := r.lookupHost(ctx, host)
+ if err != nil {
+ return
+ }
+ for _, lit := range lits {
+ host, zone := splitHostZone(lit)
+ if ip := ParseIP(host); ip != nil {
+ addr := IPAddr{IP: ip, Zone: zone}
+ addrs = append(addrs, addr)
+ }
+ }
+ return
+}
+
+func (r *Resolver) lookupPort(ctx context.Context, network, service string) (port int, err error) {
+ switch network {
+ case "ip": // no hints
+ if p, err := r.lookupPortWithNetwork(ctx, "tcp", "ip", service); err == nil {
+ return p, nil
+ }
+ return r.lookupPortWithNetwork(ctx, "udp", "ip", service)
+ case "tcp", "tcp4", "tcp6":
+ return r.lookupPortWithNetwork(ctx, "tcp", "tcp", service)
+ case "udp", "udp4", "udp6":
+ return r.lookupPortWithNetwork(ctx, "udp", "udp", service)
+ default:
+ return 0, &DNSError{Err: "unknown network", Name: network + "/" + service}
+ }
+}
+
+func (*Resolver) lookupPortWithNetwork(ctx context.Context, network, errNetwork, service string) (port int, err error) {
+ lines, err := queryCS(ctx, network, "127.0.0.1", toLower(service))
+ if err != nil {
+ if stringslite.HasSuffix(err.Error(), "can't translate service") {
+ return 0, newDNSError(errUnknownPort, errNetwork+"/"+service, "")
+ }
+ return 0, newDNSError(err, errNetwork+"/"+service, "")
+ }
+ if len(lines) == 0 {
+ return 0, newDNSError(errUnknownPort, errNetwork+"/"+service, "")
+ }
+ f := getFields(lines[0])
+ if len(f) < 2 {
+ return 0, newDNSError(errUnknownPort, errNetwork+"/"+service, "")
+ }
+ s := f[1]
+ if i := bytealg.IndexByteString(s, '!'); i >= 0 {
+ s = s[i+1:] // remove address
+ }
+ if n, _, ok := dtoi(s); ok {
+ return n, nil
+ }
+ return 0, newDNSError(errUnknownPort, errNetwork+"/"+service, "")
+}
+
+func (r *Resolver) lookupCNAME(ctx context.Context, name string) (cname string, err error) {
+ if order, conf := systemConf().hostLookupOrder(r, name); order != hostLookupCgo {
+ return r.goLookupCNAME(ctx, name, order, conf)
+ }
+
+ lines, err := queryDNS(ctx, name, "cname")
+ if err != nil {
+ if stringslite.HasSuffix(err.Error(), "dns failure") ||
+ stringslite.HasSuffix(err.Error(), "resource does not exist; negrcode 0") ||
+ stringslite.HasSuffix(err.Error(), "resource does not exist; negrcode") {
+ return absDomainName(name), nil
+ }
+ return "", handlePlan9DNSError(err, cname)
+ }
+ if len(lines) > 0 {
+ if f := getFields(lines[0]); len(f) >= 3 {
+ return f[2] + ".", nil
+ }
+ }
+ return "", &DNSError{Err: "bad response from ndb/dns", Name: name}
+}
+
+func (r *Resolver) lookupSRV(ctx context.Context, service, proto, name string) (cname string, addrs []*SRV, err error) {
+ if systemConf().mustUseGoResolver(r) {
+ return r.goLookupSRV(ctx, service, proto, name)
+ }
+ var target string
+ if service == "" && proto == "" {
+ target = name
+ } else {
+ target = "_" + service + "._" + proto + "." + name
+ }
+ lines, err := queryDNS(ctx, target, "srv")
+ if err != nil {
+ return "", nil, handlePlan9DNSError(err, name)
+ }
+ for _, line := range lines {
+ f := getFields(line)
+ if len(f) < 6 {
+ continue
+ }
+ port, _, portOk := dtoi(f[4])
+ priority, _, priorityOk := dtoi(f[3])
+ weight, _, weightOk := dtoi(f[2])
+ if !(portOk && priorityOk && weightOk) {
+ continue
+ }
+ addrs = append(addrs, &SRV{absDomainName(f[5]), uint16(port), uint16(priority), uint16(weight)})
+ cname = absDomainName(f[0])
+ }
+ byPriorityWeight(addrs).sort()
+ return
+}
+
+func (r *Resolver) lookupMX(ctx context.Context, name string) (mx []*MX, err error) {
+ if systemConf().mustUseGoResolver(r) {
+ return r.goLookupMX(ctx, name)
+ }
+ lines, err := queryDNS(ctx, name, "mx")
+ if err != nil {
+ return nil, handlePlan9DNSError(err, name)
+ }
+ for _, line := range lines {
+ f := getFields(line)
+ if len(f) < 4 {
+ continue
+ }
+ if pref, _, ok := dtoi(f[2]); ok {
+ mx = append(mx, &MX{absDomainName(f[3]), uint16(pref)})
+ }
+ }
+ byPref(mx).sort()
+ return
+}
+
+func (r *Resolver) lookupNS(ctx context.Context, name string) (ns []*NS, err error) {
+ if systemConf().mustUseGoResolver(r) {
+ return r.goLookupNS(ctx, name)
+ }
+ lines, err := queryDNS(ctx, name, "ns")
+ if err != nil {
+ return nil, handlePlan9DNSError(err, name)
+ }
+ for _, line := range lines {
+ f := getFields(line)
+ if len(f) < 3 {
+ continue
+ }
+ ns = append(ns, &NS{absDomainName(f[2])})
+ }
+ return
+}
+
+func (r *Resolver) lookupTXT(ctx context.Context, name string) (txt []string, err error) {
+ if systemConf().mustUseGoResolver(r) {
+ return r.goLookupTXT(ctx, name)
+ }
+ lines, err := queryDNS(ctx, name, "txt")
+ if err != nil {
+ return nil, handlePlan9DNSError(err, name)
+ }
+ for _, line := range lines {
+ if i := bytealg.IndexByteString(line, '\t'); i >= 0 {
+ txt = append(txt, line[i+1:])
+ }
+ }
+ return
+}
+
+func (r *Resolver) lookupAddr(ctx context.Context, addr string) (name []string, err error) {
+ if order, conf := systemConf().addrLookupOrder(r, addr); order != hostLookupCgo {
+ return r.goLookupPTR(ctx, addr, order, conf)
+ }
+ arpa, err := reverseaddr(addr)
+ if err != nil {
+ return
+ }
+ lines, err := queryDNS(ctx, arpa, "ptr")
+ if err != nil {
+ return nil, handlePlan9DNSError(err, addr)
+ }
+ for _, line := range lines {
+ f := getFields(line)
+ if len(f) < 3 {
+ continue
+ }
+ name = append(name, absDomainName(f[2]))
+ }
+ return
+}
+
+// concurrentThreadsLimit returns the number of threads we permit to
+// run concurrently doing DNS lookups.
+func concurrentThreadsLimit() int {
+ return 500
+}
diff --git a/go/src/net/lookup_test.go b/go/src/net/lookup_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..42211ed099ed1e7fe9d96c4da7328465dfd89e58
--- /dev/null
+++ b/go/src/net/lookup_test.go
@@ -0,0 +1,1652 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "context"
+ "errors"
+ "fmt"
+ "internal/testenv"
+ "net/netip"
+ "reflect"
+ "runtime"
+ "slices"
+ "strings"
+ "sync"
+ "sync/atomic"
+ "testing"
+ "time"
+)
+
+var goResolver = Resolver{PreferGo: true}
+
+func hasSuffixFold(s, suffix string) bool {
+ return strings.HasSuffix(strings.ToLower(s), strings.ToLower(suffix))
+}
+
+func lookupLocalhost(ctx context.Context, fn func(context.Context, string, string) ([]IPAddr, error), network, host string) ([]IPAddr, error) {
+ switch host {
+ case "localhost":
+ return []IPAddr{
+ {IP: IPv4(127, 0, 0, 1)},
+ {IP: IPv6loopback},
+ }, nil
+ default:
+ return fn(ctx, network, host)
+ }
+}
+
+// The Lookup APIs use various sources such as local database, DNS or
+// mDNS, and may use platform-dependent DNS stub resolver if possible.
+// The APIs accept any of forms for a query; host name in various
+// encodings, UTF-8 encoded net name, domain name, FQDN or absolute
+// FQDN, but the result would be one of the forms and it depends on
+// the circumstances.
+
+var lookupGoogleSRVTests = []struct {
+ service, proto, name string
+ cname, target string
+}{
+ {
+ "ldap", "tcp", "google.com",
+ "google.com.", "google.com.",
+ },
+ {
+ "ldap", "tcp", "google.com.",
+ "google.com.", "google.com.",
+ },
+
+ // non-standard back door
+ {
+ "", "", "_ldap._tcp.google.com",
+ "google.com.", "google.com.",
+ },
+ {
+ "", "", "_ldap._tcp.google.com.",
+ "google.com.", "google.com.",
+ },
+}
+
+var backoffDuration = [...]time.Duration{time.Second, 5 * time.Second, 30 * time.Second}
+
+func TestLookupGoogleSRV(t *testing.T) {
+ t.Parallel()
+ mustHaveExternalNetwork(t)
+
+ if runtime.GOOS == "ios" {
+ t.Skip("no resolv.conf on iOS")
+ }
+
+ if !supportsIPv4() || !*testIPv4 {
+ t.Skip("IPv4 is required")
+ }
+
+ attempts := 0
+ for i := 0; i < len(lookupGoogleSRVTests); i++ {
+ tt := lookupGoogleSRVTests[i]
+ cname, srvs, err := LookupSRV(tt.service, tt.proto, tt.name)
+ if err != nil {
+ testenv.SkipFlakyNet(t)
+ if attempts < len(backoffDuration) {
+ dur := backoffDuration[attempts]
+ t.Logf("backoff %v after failure %v\n", dur, err)
+ time.Sleep(dur)
+ attempts++
+ i--
+ continue
+ }
+ t.Fatal(err)
+ }
+ if len(srvs) == 0 {
+ t.Error("got no record")
+ }
+ if !hasSuffixFold(cname, tt.cname) {
+ t.Errorf("got %s; want %s", cname, tt.cname)
+ }
+ for _, srv := range srvs {
+ if !hasSuffixFold(srv.Target, tt.target) {
+ t.Errorf("got %v; want a record containing %s", srv, tt.target)
+ }
+ }
+ }
+}
+
+var lookupGmailMXTests = []struct {
+ name, host string
+}{
+ {"gmail.com", "google.com."},
+ {"gmail.com.", "google.com."},
+}
+
+func TestLookupGmailMX(t *testing.T) {
+ t.Parallel()
+ mustHaveExternalNetwork(t)
+
+ if runtime.GOOS == "ios" {
+ t.Skip("no resolv.conf on iOS")
+ }
+
+ if !supportsIPv4() || !*testIPv4 {
+ t.Skip("IPv4 is required")
+ }
+
+ attempts := 0
+ for i := 0; i < len(lookupGmailMXTests); i++ {
+ tt := lookupGmailMXTests[i]
+ mxs, err := LookupMX(tt.name)
+ if err != nil {
+ testenv.SkipFlakyNet(t)
+ if attempts < len(backoffDuration) {
+ dur := backoffDuration[attempts]
+ t.Logf("backoff %v after failure %v\n", dur, err)
+ time.Sleep(dur)
+ attempts++
+ i--
+ continue
+ }
+ t.Fatal(err)
+ }
+ if len(mxs) == 0 {
+ t.Error("got no record")
+ }
+ for _, mx := range mxs {
+ if !hasSuffixFold(mx.Host, tt.host) {
+ t.Errorf("got %v; want a record containing %s", mx, tt.host)
+ }
+ }
+ }
+}
+
+var lookupGmailNSTests = []struct {
+ name, host string
+}{
+ {"gmail.com", "google.com."},
+ {"gmail.com.", "google.com."},
+}
+
+func TestLookupGmailNS(t *testing.T) {
+ t.Parallel()
+ mustHaveExternalNetwork(t)
+
+ if runtime.GOOS == "ios" {
+ t.Skip("no resolv.conf on iOS")
+ }
+
+ if !supportsIPv4() || !*testIPv4 {
+ t.Skip("IPv4 is required")
+ }
+
+ attempts := 0
+ for i := 0; i < len(lookupGmailNSTests); i++ {
+ tt := lookupGmailNSTests[i]
+ nss, err := LookupNS(tt.name)
+ if err != nil {
+ testenv.SkipFlakyNet(t)
+ if attempts < len(backoffDuration) {
+ dur := backoffDuration[attempts]
+ t.Logf("backoff %v after failure %v\n", dur, err)
+ time.Sleep(dur)
+ attempts++
+ i--
+ continue
+ }
+ t.Fatal(err)
+ }
+ if len(nss) == 0 {
+ t.Error("got no record")
+ }
+ for _, ns := range nss {
+ if !hasSuffixFold(ns.Host, tt.host) {
+ t.Errorf("got %v; want a record containing %s", ns, tt.host)
+ }
+ }
+ }
+}
+
+var lookupGmailTXTTests = []struct {
+ name, txt, host string
+}{
+ {"gmail.com", "spf", "google.com"},
+ {"gmail.com.", "spf", "google.com"},
+}
+
+func TestLookupGmailTXT(t *testing.T) {
+ if runtime.GOOS == "plan9" {
+ t.Skip("skipping on plan9; see https://golang.org/issue/29722")
+ }
+ t.Parallel()
+ mustHaveExternalNetwork(t)
+
+ if runtime.GOOS == "ios" {
+ t.Skip("no resolv.conf on iOS")
+ }
+
+ if !supportsIPv4() || !*testIPv4 {
+ t.Skip("IPv4 is required")
+ }
+
+ attempts := 0
+ for i := 0; i < len(lookupGmailTXTTests); i++ {
+ tt := lookupGmailTXTTests[i]
+ txts, err := LookupTXT(tt.name)
+ if err != nil {
+ testenv.SkipFlakyNet(t)
+ if attempts < len(backoffDuration) {
+ dur := backoffDuration[attempts]
+ t.Logf("backoff %v after failure %v\n", dur, err)
+ time.Sleep(dur)
+ attempts++
+ i--
+ continue
+ }
+ t.Fatal(err)
+ }
+ if len(txts) == 0 {
+ t.Error("got no record")
+ }
+
+ if !slices.ContainsFunc(txts, func(txt string) bool {
+ return strings.Contains(txt, tt.txt) && (strings.HasSuffix(txt, tt.host) || strings.HasSuffix(txt, tt.host+"."))
+ }) {
+ t.Errorf("got %v; want a record containing %s, %s", txts, tt.txt, tt.host)
+ }
+ }
+}
+
+var lookupGooglePublicDNSAddrTests = []string{
+ "8.8.8.8",
+ "8.8.4.4",
+ "2001:4860:4860::8888",
+ "2001:4860:4860::8844",
+}
+
+func TestLookupGooglePublicDNSAddr(t *testing.T) {
+ mustHaveExternalNetwork(t)
+
+ if !supportsIPv4() || !supportsIPv6() || !*testIPv4 || !*testIPv6 {
+ t.Skip("both IPv4 and IPv6 are required")
+ }
+
+ defer dnsWaitGroup.Wait()
+
+ for _, ip := range lookupGooglePublicDNSAddrTests {
+ names, err := LookupAddr(ip)
+ if err != nil {
+ t.Fatal(err)
+ }
+ if len(names) == 0 {
+ t.Error("got no record")
+ }
+ for _, name := range names {
+ if !hasSuffixFold(name, ".google.com.") && !hasSuffixFold(name, ".google.") {
+ t.Errorf("got %q; want a record ending in .google.com. or .google.", name)
+ }
+ }
+ }
+}
+
+func TestLookupIPv6LinkLocalAddr(t *testing.T) {
+ if !supportsIPv6() || !*testIPv6 {
+ t.Skip("IPv6 is required")
+ }
+
+ defer dnsWaitGroup.Wait()
+
+ addrs, err := LookupHost("localhost")
+ if err != nil {
+ t.Fatal(err)
+ }
+ if !slices.Contains(addrs, "fe80::1%lo0") {
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+ if _, err := LookupAddr("fe80::1%lo0"); err != nil {
+ t.Error(err)
+ }
+}
+
+func TestLookupIPv6LinkLocalAddrWithZone(t *testing.T) {
+ if !supportsIPv6() || !*testIPv6 {
+ t.Skip("IPv6 is required")
+ }
+
+ ipaddrs, err := DefaultResolver.LookupIPAddr(context.Background(), "fe80::1%lo0")
+ if err != nil {
+ t.Error(err)
+ }
+ for _, addr := range ipaddrs {
+ if e, a := "lo0", addr.Zone; e != a {
+ t.Errorf("wrong zone: want %q, got %q", e, a)
+ }
+ }
+
+ addrs, err := DefaultResolver.LookupHost(context.Background(), "fe80::1%lo0")
+ if err != nil {
+ t.Error(err)
+ }
+ for _, addr := range addrs {
+ if e, a := "fe80::1%lo0", addr; e != a {
+ t.Errorf("wrong host: want %q got %q", e, a)
+ }
+ }
+}
+
+var lookupCNAMETests = []struct {
+ name, cname string
+}{
+ {"www.iana.org", "icann.org."},
+ {"www.iana.org.", "icann.org."},
+ {"www.google.com", "google.com."},
+ {"google.com", "google.com."},
+ {"cname-to-txt.go4.org", "test-txt-record.go4.org."},
+}
+
+func TestLookupCNAME(t *testing.T) {
+ mustHaveExternalNetwork(t)
+ testenv.SkipFlakyNet(t)
+
+ if !supportsIPv4() || !*testIPv4 {
+ t.Skip("IPv4 is required")
+ }
+
+ defer dnsWaitGroup.Wait()
+
+ attempts := 0
+ for i := 0; i < len(lookupCNAMETests); i++ {
+ tt := lookupCNAMETests[i]
+ cname, err := LookupCNAME(tt.name)
+ if err != nil {
+ testenv.SkipFlakyNet(t)
+ if attempts < len(backoffDuration) {
+ dur := backoffDuration[attempts]
+ t.Logf("backoff %v after failure %v\n", dur, err)
+ time.Sleep(dur)
+ attempts++
+ i--
+ continue
+ }
+ t.Fatal(err)
+ }
+ if !hasSuffixFold(cname, tt.cname) {
+ t.Errorf("got %s; want a record containing %s", cname, tt.cname)
+ }
+ }
+}
+
+var lookupGoogleHostTests = []struct {
+ name string
+}{
+ {"google.com"},
+ {"google.com."},
+}
+
+func TestLookupGoogleHost(t *testing.T) {
+ mustHaveExternalNetwork(t)
+ testenv.SkipFlakyNet(t)
+
+ if !supportsIPv4() || !*testIPv4 {
+ t.Skip("IPv4 is required")
+ }
+
+ defer dnsWaitGroup.Wait()
+
+ for _, tt := range lookupGoogleHostTests {
+ addrs, err := LookupHost(tt.name)
+ if err != nil {
+ t.Fatal(err)
+ }
+ if len(addrs) == 0 {
+ t.Error("got no record")
+ }
+ for _, addr := range addrs {
+ if ParseIP(addr) == nil {
+ t.Errorf("got %q; want a literal IP address", addr)
+ }
+ }
+ }
+}
+
+func TestLookupLongTXT(t *testing.T) {
+ testenv.SkipFlaky(t, 22857)
+ mustHaveExternalNetwork(t)
+
+ defer dnsWaitGroup.Wait()
+
+ txts, err := LookupTXT("golang.rsc.io")
+ if err != nil {
+ t.Fatal(err)
+ }
+ slices.Sort(txts)
+ want := []string{
+ strings.Repeat("abcdefghijklmnopqrstuvwxyABCDEFGHJIKLMNOPQRSTUVWXY", 10),
+ "gophers rule",
+ }
+ if !slices.Equal(txts, want) {
+ t.Fatalf("LookupTXT golang.rsc.io incorrect\nhave %q\nwant %q", txts, want)
+ }
+}
+
+var lookupGoogleIPTests = []struct {
+ name string
+}{
+ {"google.com"},
+ {"google.com."},
+}
+
+func TestLookupGoogleIP(t *testing.T) {
+ mustHaveExternalNetwork(t)
+ testenv.SkipFlakyNet(t)
+
+ if !supportsIPv4() || !*testIPv4 {
+ t.Skip("IPv4 is required")
+ }
+
+ defer dnsWaitGroup.Wait()
+
+ for _, tt := range lookupGoogleIPTests {
+ ips, err := LookupIP(tt.name)
+ if err != nil {
+ t.Fatal(err)
+ }
+ if len(ips) == 0 {
+ t.Error("got no record")
+ }
+ for _, ip := range ips {
+ if ip.To4() == nil && ip.To16() == nil {
+ t.Errorf("got %v; want an IP address", ip)
+ }
+ }
+ }
+}
+
+var revAddrTests = []struct {
+ Addr string
+ Reverse string
+ ErrPrefix string
+}{
+ {"1.2.3.4", "4.3.2.1.in-addr.arpa.", ""},
+ {"245.110.36.114", "114.36.110.245.in-addr.arpa.", ""},
+ {"::ffff:12.34.56.78", "78.56.34.12.in-addr.arpa.", ""},
+ {"::1", "1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa.", ""},
+ {"1::", "0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.1.0.0.0.ip6.arpa.", ""},
+ {"1234:567::89a:bcde", "e.d.c.b.a.9.8.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.7.6.5.0.4.3.2.1.ip6.arpa.", ""},
+ {"1234:567:fefe:bcbc:adad:9e4a:89a:bcde", "e.d.c.b.a.9.8.0.a.4.e.9.d.a.d.a.c.b.c.b.e.f.e.f.7.6.5.0.4.3.2.1.ip6.arpa.", ""},
+ {"1.2.3", "", "unrecognized address"},
+ {"1.2.3.4.5", "", "unrecognized address"},
+ {"1234:567:bcbca::89a:bcde", "", "unrecognized address"},
+ {"1234:567::bcbc:adad::89a:bcde", "", "unrecognized address"},
+}
+
+func TestReverseAddress(t *testing.T) {
+ defer dnsWaitGroup.Wait()
+ for i, tt := range revAddrTests {
+ a, err := reverseaddr(tt.Addr)
+ if len(tt.ErrPrefix) > 0 && err == nil {
+ t.Errorf("#%d: expected %q, got (error)", i, tt.ErrPrefix)
+ continue
+ }
+ if len(tt.ErrPrefix) == 0 && err != nil {
+ t.Errorf("#%d: expected , got %q (error)", i, err)
+ }
+ if err != nil && err.(*DNSError).Err != tt.ErrPrefix {
+ t.Errorf("#%d: expected %q, got %q (mismatched error)", i, tt.ErrPrefix, err.(*DNSError).Err)
+ }
+ if a != tt.Reverse {
+ t.Errorf("#%d: expected %q, got %q (reverse address)", i, tt.Reverse, a)
+ }
+ }
+}
+
+func TestDNSFlood(t *testing.T) {
+ if !*testDNSFlood {
+ t.Skip("test disabled; use -dnsflood to enable")
+ }
+
+ defer dnsWaitGroup.Wait()
+
+ var N = 5000
+ if runtime.GOOS == "darwin" || runtime.GOOS == "ios" {
+ // On Darwin this test consumes kernel threads much
+ // than other platforms for some reason.
+ // When we monitor the number of allocated Ms by
+ // observing on runtime.newm calls, we can see that it
+ // easily reaches the per process ceiling
+ // kern.num_threads when CGO_ENABLED=1 and
+ // GODEBUG=netdns=go.
+ N = 500
+ }
+
+ const timeout = 3 * time.Second
+ ctxHalfTimeout, cancel := context.WithTimeout(context.Background(), timeout/2)
+ defer cancel()
+ ctxTimeout, cancel := context.WithTimeout(context.Background(), timeout)
+ defer cancel()
+
+ c := make(chan error, 2*N)
+ for i := 0; i < N; i++ {
+ name := fmt.Sprintf("%d.net-test.golang.org", i)
+ go func() {
+ _, err := DefaultResolver.LookupIPAddr(ctxHalfTimeout, name)
+ c <- err
+ }()
+ go func() {
+ _, err := DefaultResolver.LookupIPAddr(ctxTimeout, name)
+ c <- err
+ }()
+ }
+ qstats := struct {
+ succeeded, failed int
+ timeout, temporary, other int
+ unknown int
+ }{}
+ deadline := time.After(timeout + time.Second)
+ for i := 0; i < 2*N; i++ {
+ select {
+ case <-deadline:
+ t.Fatal("deadline exceeded")
+ case err := <-c:
+ switch err := err.(type) {
+ case nil:
+ qstats.succeeded++
+ case Error:
+ qstats.failed++
+ if err.Timeout() {
+ qstats.timeout++
+ }
+ if err.Temporary() {
+ qstats.temporary++
+ }
+ if !err.Timeout() && !err.Temporary() {
+ qstats.other++
+ }
+ default:
+ qstats.failed++
+ qstats.unknown++
+ }
+ }
+ }
+
+ // A high volume of DNS queries for sub-domain of golang.org
+ // would be coordinated by authoritative or recursive server,
+ // or stub resolver which implements query-response rate
+ // limitation, so we can expect some query successes and more
+ // failures including timeout, temporary and other here.
+ // As a rule, unknown must not be shown but it might possibly
+ // happen due to issue 4856 for now.
+ t.Logf("%v succeeded, %v failed (%v timeout, %v temporary, %v other, %v unknown)", qstats.succeeded, qstats.failed, qstats.timeout, qstats.temporary, qstats.other, qstats.unknown)
+}
+
+func TestLookupDotsWithLocalSource(t *testing.T) {
+ if !supportsIPv4() || !*testIPv4 {
+ t.Skip("IPv4 is required")
+ }
+
+ mustHaveExternalNetwork(t)
+
+ defer dnsWaitGroup.Wait()
+
+ for i, fn := range []func() func(){forceGoDNS, forceCgoDNS} {
+ fixup := fn()
+ if fixup == nil {
+ continue
+ }
+ names, err := LookupAddr("127.0.0.1")
+ fixup()
+ if err != nil {
+ t.Logf("#%d: %v", i, err)
+ continue
+ }
+ mode := "netgo"
+ if i == 1 {
+ mode = "netcgo"
+ }
+ loop:
+ for i, name := range names {
+ if strings.Index(name, ".") == len(name)-1 { // "localhost" not "localhost."
+ for j := range names {
+ if j == i {
+ continue
+ }
+ if names[j] == name[:len(name)-1] {
+ // It's OK if we find the name without the dot,
+ // as some systems say 127.0.0.1 localhost localhost.
+ continue loop
+ }
+ }
+ t.Errorf("%s: got %s; want %s", mode, name, name[:len(name)-1])
+ } else if strings.Contains(name, ".") && !strings.HasSuffix(name, ".") { // "localhost.localdomain." not "localhost.localdomain"
+ t.Errorf("%s: got %s; want name ending with trailing dot", mode, name)
+ }
+ }
+ }
+}
+
+func TestLookupDotsWithRemoteSource(t *testing.T) {
+ if runtime.GOOS == "darwin" || runtime.GOOS == "ios" {
+ testenv.SkipFlaky(t, 27992)
+ }
+ mustHaveExternalNetwork(t)
+ testenv.SkipFlakyNet(t)
+
+ if !supportsIPv4() || !*testIPv4 {
+ t.Skip("IPv4 is required")
+ }
+
+ if runtime.GOOS == "ios" {
+ t.Skip("no resolv.conf on iOS")
+ }
+
+ defer dnsWaitGroup.Wait()
+
+ if fixup := forceGoDNS(); fixup != nil {
+ testDots(t, "go")
+ fixup()
+ }
+ if fixup := forceCgoDNS(); fixup != nil {
+ testDots(t, "cgo")
+ fixup()
+ }
+}
+
+func testDots(t *testing.T, mode string) {
+ names, err := LookupAddr("8.8.8.8") // Google dns server
+ if err != nil {
+ t.Errorf("LookupAddr(8.8.8.8): %v (mode=%v)", err, mode)
+ } else {
+ for _, name := range names {
+ if !hasSuffixFold(name, ".google.com.") && !hasSuffixFold(name, ".google.") {
+ t.Errorf("LookupAddr(8.8.8.8) = %v, want names ending in .google.com or .google with trailing dot (mode=%v)", names, mode)
+ break
+ }
+ }
+ }
+
+ cname, err := LookupCNAME("www.mit.edu")
+ if err != nil {
+ t.Errorf("LookupCNAME(www.mit.edu, mode=%v): %v", mode, err)
+ } else if !strings.HasSuffix(cname, ".") {
+ t.Errorf("LookupCNAME(www.mit.edu) = %v, want cname ending in . with trailing dot (mode=%v)", cname, mode)
+ }
+
+ mxs, err := LookupMX("google.com")
+ if err != nil {
+ t.Errorf("LookupMX(google.com): %v (mode=%v)", err, mode)
+ } else {
+ for _, mx := range mxs {
+ if !hasSuffixFold(mx.Host, ".google.com.") {
+ t.Errorf("LookupMX(google.com) = %v, want names ending in .google.com. with trailing dot (mode=%v)", mxString(mxs), mode)
+ break
+ }
+ }
+ }
+
+ nss, err := LookupNS("google.com")
+ if err != nil {
+ t.Errorf("LookupNS(google.com): %v (mode=%v)", err, mode)
+ } else {
+ for _, ns := range nss {
+ if !hasSuffixFold(ns.Host, ".google.com.") {
+ t.Errorf("LookupNS(google.com) = %v, want names ending in .google.com. with trailing dot (mode=%v)", nsString(nss), mode)
+ break
+ }
+ }
+ }
+
+ cname, srvs, err := LookupSRV("ldap", "tcp", "google.com")
+ if err != nil {
+ t.Errorf("LookupSRV(ldap, tcp, google.com): %v (mode=%v)", err, mode)
+ } else {
+ if !hasSuffixFold(cname, ".google.com.") {
+ t.Errorf("LookupSRV(ldap, tcp, google.com) returned cname=%v, want name ending in .google.com. with trailing dot (mode=%v)", cname, mode)
+ }
+ for _, srv := range srvs {
+ if !hasSuffixFold(srv.Target, ".google.com.") {
+ t.Errorf("LookupSRV(ldap, tcp, google.com) returned addrs=%v, want names ending in .google.com. with trailing dot (mode=%v)", srvString(srvs), mode)
+ break
+ }
+ }
+ }
+}
+
+func mxString(mxs []*MX) string {
+ var buf strings.Builder
+ sep := ""
+ fmt.Fprintf(&buf, "[")
+ for _, mx := range mxs {
+ fmt.Fprintf(&buf, "%s%s:%d", sep, mx.Host, mx.Pref)
+ sep = " "
+ }
+ fmt.Fprintf(&buf, "]")
+ return buf.String()
+}
+
+func nsString(nss []*NS) string {
+ var buf strings.Builder
+ sep := ""
+ fmt.Fprintf(&buf, "[")
+ for _, ns := range nss {
+ fmt.Fprintf(&buf, "%s%s", sep, ns.Host)
+ sep = " "
+ }
+ fmt.Fprintf(&buf, "]")
+ return buf.String()
+}
+
+func srvString(srvs []*SRV) string {
+ var buf strings.Builder
+ sep := ""
+ fmt.Fprintf(&buf, "[")
+ for _, srv := range srvs {
+ fmt.Fprintf(&buf, "%s%s:%d:%d:%d", sep, srv.Target, srv.Port, srv.Priority, srv.Weight)
+ sep = " "
+ }
+ fmt.Fprintf(&buf, "]")
+ return buf.String()
+}
+
+func TestLookupPort(t *testing.T) {
+ // See https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml
+ //
+ // Please be careful about adding new test cases.
+ // There are platforms which have incomplete mappings for
+ // restricted resource access and security reasons.
+ type test struct {
+ network string
+ name string
+ port int
+ ok bool
+ }
+ var tests = []test{
+ {"tcp", "0", 0, true},
+ {"udp", "0", 0, true},
+ {"udp", "domain", 53, true},
+
+ {"--badnet--", "zzz", 0, false},
+ {"tcp", "--badport--", 0, false},
+ {"tcp", "-1", 0, false},
+ {"tcp", "65536", 0, false},
+ {"udp", "-1", 0, false},
+ {"udp", "65536", 0, false},
+ {"tcp", "123456789", 0, false},
+ {"tcp", "bad\x00port", 0, false},
+
+ // Issue 13610: LookupPort("tcp", "")
+ {"tcp", "", 0, true},
+ {"tcp4", "", 0, true},
+ {"tcp6", "", 0, true},
+ {"udp", "", 0, true},
+ {"udp4", "", 0, true},
+ {"udp6", "", 0, true},
+ }
+
+ switch runtime.GOOS {
+ case "android":
+ if netGoBuildTag {
+ t.Skipf("not supported on %s without cgo; see golang.org/issues/14576", runtime.GOOS)
+ }
+ default:
+ tests = append(tests, test{"tcp", "http", 80, true})
+ }
+
+ for _, tt := range tests {
+ port, err := LookupPort(tt.network, tt.name)
+ if port != tt.port || (err == nil) != tt.ok {
+ t.Errorf("LookupPort(%q, %q) = %d, %v; want %d, error=%t", tt.network, tt.name, port, err, tt.port, !tt.ok)
+ }
+ if err != nil {
+ if perr := parseLookupPortError(err); perr != nil {
+ t.Error(perr)
+ }
+ }
+ }
+}
+
+// Like TestLookupPort but with minimal tests that should always pass
+// because the answers are baked-in to the net package.
+func TestLookupPort_Minimal(t *testing.T) {
+ type test struct {
+ network string
+ name string
+ port int
+ }
+ var tests = []test{
+ {"tcp", "http", 80},
+ {"tcp", "HTTP", 80}, // case shouldn't matter
+ {"tcp", "https", 443},
+ {"tcp", "ssh", 22},
+ {"tcp", "gopher", 70},
+ {"tcp4", "http", 80},
+ {"tcp6", "http", 80},
+ }
+
+ for _, tt := range tests {
+ port, err := LookupPort(tt.network, tt.name)
+ if port != tt.port || err != nil {
+ t.Errorf("LookupPort(%q, %q) = %d, %v; want %d, error=nil", tt.network, tt.name, port, err, tt.port)
+ }
+ }
+}
+
+func TestLookupProtocol_Minimal(t *testing.T) {
+ type test struct {
+ name string
+ want int
+ }
+ var tests = []test{
+ {"tcp", 6},
+ {"TcP", 6}, // case shouldn't matter
+ {"icmp", 1},
+ {"igmp", 2},
+ {"udp", 17},
+ {"ipv6-icmp", 58},
+ }
+
+ for _, tt := range tests {
+ got, err := lookupProtocol(context.Background(), tt.name)
+ if got != tt.want || err != nil {
+ t.Errorf("LookupProtocol(%q) = %d, %v; want %d, error=nil", tt.name, got, err, tt.want)
+ }
+ }
+
+}
+
+func TestLookupNonLDH(t *testing.T) {
+ defer dnsWaitGroup.Wait()
+
+ if fixup := forceGoDNS(); fixup != nil {
+ defer fixup()
+ }
+
+ // "LDH" stands for letters, digits, and hyphens and is the usual
+ // description of standard DNS names.
+ // This test is checking that other kinds of names are reported
+ // as not found, not reported as invalid names.
+ addrs, err := LookupHost("!!!.###.bogus..domain.")
+ if err == nil {
+ t.Fatalf("lookup succeeded: %v", addrs)
+ }
+ if !strings.HasSuffix(err.Error(), errNoSuchHost.Error()) {
+ t.Fatalf("lookup error = %v, want %v", err, errNoSuchHost)
+ }
+ if !err.(*DNSError).IsNotFound {
+ t.Fatalf("lookup error = %v, want true", err.(*DNSError).IsNotFound)
+ }
+}
+
+func TestLookupContextCancel(t *testing.T) {
+ mustHaveExternalNetwork(t)
+ testenv.SkipFlakyNet(t)
+
+ origTestHookLookupIP := testHookLookupIP
+ defer func() {
+ dnsWaitGroup.Wait()
+ testHookLookupIP = origTestHookLookupIP
+ }()
+
+ lookupCtx, cancelLookup := context.WithCancel(context.Background())
+ unblockLookup := make(chan struct{})
+
+ // Set testHookLookupIP to start a new, concurrent call to LookupIPAddr
+ // and cancel the original one, then block until the canceled call has returned
+ // (ensuring that it has performed any synchronous cleanup).
+ testHookLookupIP = func(
+ ctx context.Context,
+ fn func(context.Context, string, string) ([]IPAddr, error),
+ network string,
+ host string,
+ ) ([]IPAddr, error) {
+ select {
+ case <-unblockLookup:
+ default:
+ // Start a concurrent LookupIPAddr for the same host while the caller is
+ // still blocked, and sleep a little to give it time to be deduplicated
+ // before we cancel (and unblock) the caller.
+ // (If the timing doesn't quite work out, we'll end up testing sequential
+ // calls instead of concurrent ones, but the test should still pass.)
+ t.Logf("starting concurrent LookupIPAddr")
+ dnsWaitGroup.Add(1)
+ go func() {
+ defer dnsWaitGroup.Done()
+ _, err := DefaultResolver.LookupIPAddr(context.Background(), host)
+ if err != nil {
+ t.Error(err)
+ }
+ }()
+ time.Sleep(1 * time.Millisecond)
+ }
+
+ cancelLookup()
+ <-unblockLookup
+ // If the concurrent lookup above is deduplicated to this one
+ // (as we expect to happen most of the time), it is important
+ // that the original call does not cancel the shared Context.
+ // (See https://go.dev/issue/22724.) Explicitly check for
+ // cancellation now, just in case fn itself doesn't notice it.
+ if err := ctx.Err(); err != nil {
+ t.Logf("testHookLookupIP canceled")
+ return nil, err
+ }
+ t.Logf("testHookLookupIP performing lookup")
+ return fn(ctx, network, host)
+ }
+
+ _, err := DefaultResolver.LookupIPAddr(lookupCtx, "google.com")
+ if dnsErr, ok := err.(*DNSError); !ok || dnsErr.Err != errCanceled.Error() {
+ t.Errorf("unexpected error from canceled, blocked LookupIPAddr: %v", err)
+ }
+ close(unblockLookup)
+}
+
+// Issue 24330: treat the nil *Resolver like a zero value. Verify nothing
+// crashes if nil is used.
+func TestNilResolverLookup(t *testing.T) {
+ mustHaveExternalNetwork(t)
+ var r *Resolver = nil
+ ctx := context.Background()
+
+ // Don't care about the results, just that nothing panics:
+ r.LookupAddr(ctx, "8.8.8.8")
+ r.LookupCNAME(ctx, "google.com")
+ r.LookupHost(ctx, "google.com")
+ r.LookupIPAddr(ctx, "google.com")
+ r.LookupIP(ctx, "ip", "google.com")
+ r.LookupMX(ctx, "gmail.com")
+ r.LookupNS(ctx, "google.com")
+ r.LookupPort(ctx, "tcp", "smtp")
+ r.LookupSRV(ctx, "service", "proto", "name")
+ r.LookupTXT(ctx, "gmail.com")
+}
+
+// TestLookupHostCancel verifies that lookup works even after many
+// canceled lookups (see golang.org/issue/24178 for details).
+func TestLookupHostCancel(t *testing.T) {
+ mustHaveExternalNetwork(t)
+ testenv.SkipFlakyNet(t)
+ t.Parallel() // Executes 600ms worth of sequential sleeps.
+
+ const (
+ google = "www.google.com"
+ invalidDomain = "invalid.invalid" // RFC 2606 reserves .invalid
+ n = 600 // this needs to be larger than threadLimit size
+ )
+
+ _, err := LookupHost(google)
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ ctx, cancel := context.WithCancel(context.Background())
+ cancel()
+ for i := 0; i < n; i++ {
+ addr, err := DefaultResolver.LookupHost(ctx, invalidDomain)
+ if err == nil {
+ t.Fatalf("LookupHost(%q): returns %v, but should fail", invalidDomain, addr)
+ }
+
+ // Don't verify what the actual error is.
+ // We know that it must be non-nil because the domain is invalid,
+ // but we don't have any guarantee that LookupHost actually bothers
+ // to check for cancellation on the fast path.
+ // (For example, it could use a local cache to avoid blocking entirely.)
+
+ // The lookup may deduplicate in-flight requests, so give it time to settle
+ // in between.
+ time.Sleep(time.Millisecond * 1)
+ }
+
+ _, err = LookupHost(google)
+ if err != nil {
+ t.Fatal(err)
+ }
+}
+
+type lookupCustomResolver struct {
+ *Resolver
+ mu sync.RWMutex
+ dialed bool
+}
+
+func (lcr *lookupCustomResolver) dial() func(ctx context.Context, network, address string) (Conn, error) {
+ return func(ctx context.Context, network, address string) (Conn, error) {
+ lcr.mu.Lock()
+ lcr.dialed = true
+ lcr.mu.Unlock()
+ return Dial(network, address)
+ }
+}
+
+// TestConcurrentPreferGoResolversDial tests that multiple resolvers with the
+// PreferGo option used concurrently are all dialed properly.
+func TestConcurrentPreferGoResolversDial(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9":
+ // TODO: plan9 implementation of the resolver uses the Dial function since
+ // https://go.dev/cl/409234, this test could probably be reenabled.
+ t.Skipf("skip on %v", runtime.GOOS)
+ }
+
+ testenv.MustHaveExternalNetwork(t)
+ testenv.SkipFlakyNet(t)
+
+ defer dnsWaitGroup.Wait()
+
+ resolvers := make([]*lookupCustomResolver, 2)
+ for i := range resolvers {
+ cs := lookupCustomResolver{Resolver: &Resolver{PreferGo: true}}
+ cs.Dial = cs.dial()
+ resolvers[i] = &cs
+ }
+
+ var wg sync.WaitGroup
+ wg.Add(len(resolvers))
+ for i, resolver := range resolvers {
+ go func(r *Resolver, index int) {
+ defer wg.Done()
+ _, err := r.LookupIPAddr(context.Background(), "google.com")
+ if err != nil {
+ t.Errorf("lookup failed for resolver %d: %q", index, err)
+ }
+ }(resolver.Resolver, i)
+ }
+ wg.Wait()
+
+ if t.Failed() {
+ t.FailNow()
+ }
+
+ for i, resolver := range resolvers {
+ if !resolver.dialed {
+ t.Errorf("custom resolver %d not dialed during lookup", i)
+ }
+ }
+}
+
+var ipVersionTests = []struct {
+ network string
+ version byte
+}{
+ {"tcp", 0},
+ {"tcp4", '4'},
+ {"tcp6", '6'},
+ {"udp", 0},
+ {"udp4", '4'},
+ {"udp6", '6'},
+ {"ip", 0},
+ {"ip4", '4'},
+ {"ip6", '6'},
+ {"ip7", 0},
+ {"", 0},
+}
+
+func TestIPVersion(t *testing.T) {
+ for _, tt := range ipVersionTests {
+ if version := ipVersion(tt.network); version != tt.version {
+ t.Errorf("Family for: %s. Expected: %s, Got: %s", tt.network,
+ string(tt.version), string(version))
+ }
+ }
+}
+
+// Issue 28600: The context that is used to lookup ips should always
+// preserve the values from the context that was passed into LookupIPAddr.
+func TestLookupIPAddrPreservesContextValues(t *testing.T) {
+ origTestHookLookupIP := testHookLookupIP
+ defer func() { testHookLookupIP = origTestHookLookupIP }()
+
+ keyValues := []struct {
+ key, value any
+ }{
+ {"key-1", 12},
+ {384, "value2"},
+ {new(float64), 137},
+ }
+ ctx := context.Background()
+ for _, kv := range keyValues {
+ ctx = context.WithValue(ctx, kv.key, kv.value)
+ }
+
+ wantIPs := []IPAddr{
+ {IP: IPv4(127, 0, 0, 1)},
+ {IP: IPv6loopback},
+ }
+
+ checkCtxValues := func(ctx_ context.Context, fn func(context.Context, string, string) ([]IPAddr, error), network, host string) ([]IPAddr, error) {
+ for _, kv := range keyValues {
+ g, w := ctx_.Value(kv.key), kv.value
+ if !reflect.DeepEqual(g, w) {
+ t.Errorf("Value lookup:\n\tGot: %v\n\tWant: %v", g, w)
+ }
+ }
+ return wantIPs, nil
+ }
+ testHookLookupIP = checkCtxValues
+
+ resolvers := []*Resolver{
+ nil,
+ new(Resolver),
+ }
+
+ for i, resolver := range resolvers {
+ gotIPs, err := resolver.LookupIPAddr(ctx, "golang.org")
+ if err != nil {
+ t.Errorf("Resolver #%d: unexpected error: %v", i, err)
+ }
+ if !reflect.DeepEqual(gotIPs, wantIPs) {
+ t.Errorf("#%d: mismatched IPAddr results\n\tGot: %v\n\tWant: %v", i, gotIPs, wantIPs)
+ }
+ }
+}
+
+// Issue 30521: The lookup group should call the resolver for each network.
+func TestLookupIPAddrConcurrentCallsForNetworks(t *testing.T) {
+ origTestHookLookupIP := testHookLookupIP
+ defer func() { testHookLookupIP = origTestHookLookupIP }()
+
+ queries := [][]string{
+ {"udp", "golang.org"},
+ {"udp4", "golang.org"},
+ {"udp6", "golang.org"},
+ {"udp", "golang.org"},
+ {"udp", "golang.org"},
+ }
+ results := map[[2]string][]IPAddr{
+ {"udp", "golang.org"}: {
+ {IP: IPv4(127, 0, 0, 1)},
+ {IP: IPv6loopback},
+ },
+ {"udp4", "golang.org"}: {
+ {IP: IPv4(127, 0, 0, 1)},
+ },
+ {"udp6", "golang.org"}: {
+ {IP: IPv6loopback},
+ },
+ }
+ calls := int32(0)
+ waitCh := make(chan struct{})
+ testHookLookupIP = func(ctx context.Context, fn func(context.Context, string, string) ([]IPAddr, error), network, host string) ([]IPAddr, error) {
+ // We'll block until this is called one time for each different
+ // expected result. This will ensure that the lookup group would wait
+ // for the existing call if it was to be reused.
+ if atomic.AddInt32(&calls, 1) == int32(len(results)) {
+ close(waitCh)
+ }
+ select {
+ case <-waitCh:
+ case <-ctx.Done():
+ return nil, ctx.Err()
+ }
+ return results[[2]string{network, host}], nil
+ }
+
+ ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+ defer cancel()
+ wg := sync.WaitGroup{}
+ for _, q := range queries {
+ network := q[0]
+ host := q[1]
+ wg.Add(1)
+ go func() {
+ defer wg.Done()
+ gotIPs, err := DefaultResolver.lookupIPAddr(ctx, network, host)
+ if err != nil {
+ t.Errorf("lookupIPAddr(%v, %v): unexpected error: %v", network, host, err)
+ }
+ wantIPs := results[[2]string{network, host}]
+ if !reflect.DeepEqual(gotIPs, wantIPs) {
+ t.Errorf("lookupIPAddr(%v, %v): mismatched IPAddr results\n\tGot: %v\n\tWant: %v", network, host, gotIPs, wantIPs)
+ }
+ }()
+ }
+ wg.Wait()
+}
+
+// Issue 53995: Resolver.LookupIP should return error for empty host name.
+func TestResolverLookupIPWithEmptyHost(t *testing.T) {
+ _, err := DefaultResolver.LookupIP(context.Background(), "ip", "")
+ if err == nil {
+ t.Fatal("DefaultResolver.LookupIP for empty host success, want no host error")
+ }
+ if !strings.HasSuffix(err.Error(), errNoSuchHost.Error()) {
+ t.Fatalf("lookup error = %v, want %v", err, errNoSuchHost)
+ }
+}
+
+func TestWithUnexpiredValuesPreserved(t *testing.T) {
+ ctx, cancel := context.WithCancel(context.Background())
+
+ // Insert a value into it.
+ key, value := "key-1", 2
+ ctx = context.WithValue(ctx, key, value)
+
+ // Now use the "values preserving context" like
+ // we would for LookupIPAddr. See Issue 28600.
+ ctx = withUnexpiredValuesPreserved(ctx)
+
+ // Lookup before expiry.
+ if g, w := ctx.Value(key), value; g != w {
+ t.Errorf("Lookup before expiry: Got %v Want %v", g, w)
+ }
+
+ // Cancel the context.
+ cancel()
+
+ // Lookup after expiry should return nil
+ if g := ctx.Value(key); g != nil {
+ t.Errorf("Lookup after expiry: Got %v want nil", g)
+ }
+}
+
+// Issue 31597: don't panic on null byte in name
+func TestLookupNullByte(t *testing.T) {
+ testenv.MustHaveExternalNetwork(t)
+ testenv.SkipFlakyNet(t)
+ LookupHost("foo\x00bar") // check that it doesn't panic; it used to on Windows
+}
+
+func TestResolverLookupIP(t *testing.T) {
+ testenv.MustHaveExternalNetwork(t)
+
+ v4Ok := supportsIPv4() && *testIPv4
+ v6Ok := supportsIPv6() && *testIPv6
+
+ defer dnsWaitGroup.Wait()
+
+ for _, impl := range []struct {
+ name string
+ fn func() func()
+ }{
+ {"go", forceGoDNS},
+ {"cgo", forceCgoDNS},
+ } {
+ t.Run("implementation: "+impl.name, func(t *testing.T) {
+ fixup := impl.fn()
+ if fixup == nil {
+ t.Skip("not supported")
+ }
+ defer fixup()
+
+ for _, network := range []string{"ip", "ip4", "ip6"} {
+ t.Run("network: "+network, func(t *testing.T) {
+ switch {
+ case network == "ip4" && !v4Ok:
+ t.Skip("IPv4 is not supported")
+ case network == "ip6" && !v6Ok:
+ t.Skip("IPv6 is not supported")
+ }
+
+ // google.com has both A and AAAA records.
+ const host = "google.com"
+ ips, err := DefaultResolver.LookupIP(context.Background(), network, host)
+ if err != nil {
+ testenv.SkipFlakyNet(t)
+ t.Fatalf("DefaultResolver.LookupIP(%q, %q): failed with unexpected error: %v", network, host, err)
+ }
+
+ var v4Addrs []netip.Addr
+ var v6Addrs []netip.Addr
+ for _, ip := range ips {
+ if addr, ok := netip.AddrFromSlice(ip); ok {
+ if addr.Is4() {
+ v4Addrs = append(v4Addrs, addr)
+ } else {
+ v6Addrs = append(v6Addrs, addr)
+ }
+ } else {
+ t.Fatalf("IP=%q is neither IPv4 nor IPv6", ip)
+ }
+ }
+
+ // Check that we got the expected addresses.
+ if network == "ip4" || network == "ip" && v4Ok {
+ if len(v4Addrs) == 0 {
+ t.Errorf("DefaultResolver.LookupIP(%q, %q): no IPv4 addresses", network, host)
+ }
+ }
+ if network == "ip6" || network == "ip" && v6Ok {
+ if len(v6Addrs) == 0 {
+ t.Errorf("DefaultResolver.LookupIP(%q, %q): no IPv6 addresses", network, host)
+ }
+ }
+
+ // Check that we didn't get any unexpected addresses.
+ if network == "ip6" && len(v4Addrs) > 0 {
+ t.Errorf("DefaultResolver.LookupIP(%q, %q): unexpected IPv4 addresses: %v", network, host, v4Addrs)
+ }
+ if network == "ip4" && len(v6Addrs) > 0 {
+ t.Errorf("DefaultResolver.LookupIP(%q, %q): unexpected IPv6 or IPv4-mapped IPv6 addresses: %v", network, host, v6Addrs)
+ }
+ })
+ }
+ })
+ }
+}
+
+// A context timeout should still return a DNSError.
+func TestDNSTimeout(t *testing.T) {
+ origTestHookLookupIP := testHookLookupIP
+ defer func() { testHookLookupIP = origTestHookLookupIP }()
+ defer dnsWaitGroup.Wait()
+
+ timeoutHookGo := make(chan bool, 1)
+ timeoutHook := func(ctx context.Context, fn func(context.Context, string, string) ([]IPAddr, error), network, host string) ([]IPAddr, error) {
+ <-timeoutHookGo
+ return nil, context.DeadlineExceeded
+ }
+ testHookLookupIP = timeoutHook
+
+ checkErr := func(err error) {
+ t.Helper()
+ if err == nil {
+ t.Error("expected an error")
+ } else if dnserr, ok := err.(*DNSError); !ok {
+ t.Errorf("got error type %T, want %T", err, (*DNSError)(nil))
+ } else if !dnserr.IsTimeout {
+ t.Errorf("got error %#v, want IsTimeout == true", dnserr)
+ } else if isTimeout := dnserr.Timeout(); !isTimeout {
+ t.Errorf("got err.Timeout() == %t, want true", isTimeout)
+ }
+ }
+
+ // Single lookup.
+ timeoutHookGo <- true
+ _, err := LookupIP("golang.org")
+ checkErr(err)
+
+ // Double lookup.
+ var err1, err2 error
+ var wg sync.WaitGroup
+ wg.Add(2)
+ go func() {
+ defer wg.Done()
+ _, err1 = LookupIP("golang1.org")
+ }()
+ go func() {
+ defer wg.Done()
+ _, err2 = LookupIP("golang1.org")
+ }()
+ close(timeoutHookGo)
+ wg.Wait()
+ checkErr(err1)
+ checkErr(err2)
+
+ // Double lookup with context.
+ timeoutHookGo = make(chan bool)
+ ctx, cancel := context.WithTimeout(context.Background(), time.Nanosecond)
+ wg.Add(2)
+ go func() {
+ defer wg.Done()
+ _, err1 = DefaultResolver.LookupIPAddr(ctx, "golang2.org")
+ }()
+ go func() {
+ defer wg.Done()
+ _, err2 = DefaultResolver.LookupIPAddr(ctx, "golang2.org")
+ }()
+ time.Sleep(10 * time.Nanosecond)
+ close(timeoutHookGo)
+ wg.Wait()
+ checkErr(err1)
+ checkErr(err2)
+ cancel()
+}
+
+func TestLookupNoData(t *testing.T) {
+ if runtime.GOOS == "plan9" {
+ t.Skip("not supported on plan9")
+ }
+
+ mustHaveExternalNetwork(t)
+
+ testLookupNoData(t, "default resolver")
+
+ func() {
+ defer forceGoDNS()()
+ testLookupNoData(t, "forced go resolver")
+ }()
+
+ func() {
+ defer forceCgoDNS()()
+ testLookupNoData(t, "forced cgo resolver")
+ }()
+}
+
+func testLookupNoData(t *testing.T, prefix string) {
+ attempts := 0
+ for {
+ // Domain that doesn't have any A/AAAA RRs, but has different one (in this case a TXT),
+ // so that it returns an empty response without any error codes (NXDOMAIN).
+ _, err := LookupHost("golang.rsc.io.")
+ if err == nil {
+ t.Errorf("%v: unexpected success", prefix)
+ return
+ }
+
+ dnsErr, ok := errors.AsType[*DNSError](err)
+ if ok {
+ succeeded := true
+ if !dnsErr.IsNotFound {
+ succeeded = false
+ t.Logf("%v: IsNotFound is set to false", prefix)
+ }
+
+ if dnsErr.Err != errNoSuchHost.Error() {
+ succeeded = false
+ t.Logf("%v: error message is not equal to: %v", prefix, errNoSuchHost.Error())
+ }
+
+ if succeeded {
+ return
+ }
+ }
+
+ testenv.SkipFlakyNet(t)
+ if attempts < len(backoffDuration) {
+ dur := backoffDuration[attempts]
+ t.Logf("%v: backoff %v after failure %v\n", prefix, dur, err)
+ time.Sleep(dur)
+ attempts++
+ continue
+ }
+
+ t.Errorf("%v: unexpected error: %v", prefix, err)
+ return
+ }
+}
+
+func TestLookupPortNotFound(t *testing.T) {
+ allResolvers(t, func(t *testing.T) {
+ _, err := LookupPort("udp", "_-unknown-service-")
+ if dnsErr, ok := errors.AsType[*DNSError](err); !ok || !dnsErr.IsNotFound {
+ t.Fatalf("unexpected error: %v", err)
+ }
+ })
+}
+
+// submissions service is only available through a tcp network, see:
+// https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=submissions
+var tcpOnlyService = func() string {
+ // plan9 does not have submissions service defined in the service database.
+ if runtime.GOOS == "plan9" {
+ return "https"
+ }
+ return "submissions"
+}()
+
+func TestLookupPortDifferentNetwork(t *testing.T) {
+ allResolvers(t, func(t *testing.T) {
+ _, err := LookupPort("udp", tcpOnlyService)
+ if dnsErr, ok := errors.AsType[*DNSError](err); !ok || !dnsErr.IsNotFound {
+ t.Fatalf("unexpected error: %v", err)
+ }
+ })
+}
+
+func TestLookupPortEmptyNetworkString(t *testing.T) {
+ allResolvers(t, func(t *testing.T) {
+ _, err := LookupPort("", tcpOnlyService)
+ if err != nil {
+ t.Fatalf("unexpected error: %v", err)
+ }
+ })
+}
+
+func TestLookupPortIPNetworkString(t *testing.T) {
+ allResolvers(t, func(t *testing.T) {
+ _, err := LookupPort("ip", tcpOnlyService)
+ if err != nil {
+ t.Fatalf("unexpected error: %v", err)
+ }
+ })
+}
+
+func TestLookupNoSuchHost(t *testing.T) {
+ mustHaveExternalNetwork(t)
+
+ const testNXDOMAIN = "invalid.invalid."
+ const testNODATA = "_ldap._tcp.google.com."
+
+ tests := []struct {
+ name string
+ query func() error
+ }{
+ {
+ name: "LookupCNAME NXDOMAIN",
+ query: func() error {
+ _, err := LookupCNAME(testNXDOMAIN)
+ return err
+ },
+ },
+ {
+ name: "LookupHost NXDOMAIN",
+ query: func() error {
+ _, err := LookupHost(testNXDOMAIN)
+ return err
+ },
+ },
+ {
+ name: "LookupHost NODATA",
+ query: func() error {
+ _, err := LookupHost(testNODATA)
+ return err
+ },
+ },
+ {
+ name: "LookupMX NXDOMAIN",
+ query: func() error {
+ _, err := LookupMX(testNXDOMAIN)
+ return err
+ },
+ },
+ {
+ name: "LookupMX NODATA",
+ query: func() error {
+ _, err := LookupMX(testNODATA)
+ return err
+ },
+ },
+ {
+ name: "LookupNS NXDOMAIN",
+ query: func() error {
+ _, err := LookupNS(testNXDOMAIN)
+ return err
+ },
+ },
+ {
+ name: "LookupNS NODATA",
+ query: func() error {
+ _, err := LookupNS(testNODATA)
+ return err
+ },
+ },
+ {
+ name: "LookupSRV NXDOMAIN",
+ query: func() error {
+ _, _, err := LookupSRV("unknown", "tcp", testNXDOMAIN)
+ return err
+ },
+ },
+ {
+ name: "LookupTXT NXDOMAIN",
+ query: func() error {
+ _, err := LookupTXT(testNXDOMAIN)
+ return err
+ },
+ },
+ {
+ name: "LookupTXT NODATA",
+ query: func() error {
+ _, err := LookupTXT(testNODATA)
+ return err
+ },
+ },
+ }
+
+ for _, v := range tests {
+ t.Run(v.name, func(t *testing.T) {
+ allResolvers(t, func(t *testing.T) {
+ attempts := 0
+ for {
+ err := v.query()
+ if err == nil {
+ t.Errorf("unexpected success")
+ return
+ }
+ if dnsErr, ok := err.(*DNSError); ok {
+ succeeded := true
+ if !dnsErr.IsNotFound {
+ succeeded = false
+ t.Log("IsNotFound is set to false")
+ }
+ if dnsErr.Err != errNoSuchHost.Error() {
+ succeeded = false
+ t.Logf("error message is not equal to: %v", errNoSuchHost.Error())
+ }
+ if succeeded {
+ return
+ }
+ }
+ testenv.SkipFlakyNet(t)
+ if attempts < len(backoffDuration) {
+ dur := backoffDuration[attempts]
+ t.Logf("backoff %v after failure %v\n", dur, err)
+ time.Sleep(dur)
+ attempts++
+ continue
+ }
+ t.Errorf("unexpected error: %v", err)
+ return
+ }
+ })
+ })
+ }
+}
+
+func TestDNSErrorUnwrap(t *testing.T) {
+ if runtime.GOOS == "plan9" {
+ // The Plan 9 implementation of the resolver doesn't use the Dial function yet. See https://go.dev/cl/409234
+ t.Skip("skipping on plan9")
+ }
+ rDeadlineExcceeded := &Resolver{PreferGo: true, Dial: func(ctx context.Context, network, address string) (Conn, error) {
+ return nil, context.DeadlineExceeded
+ }}
+ rCancelled := &Resolver{PreferGo: true, Dial: func(ctx context.Context, network, address string) (Conn, error) {
+ return nil, context.Canceled
+ }}
+
+ _, err := rDeadlineExcceeded.LookupHost(context.Background(), "test.go.dev")
+ if !errors.Is(err, context.DeadlineExceeded) {
+ t.Errorf("errors.Is(err, context.DeadlineExceeded) = false; want = true")
+ }
+
+ _, err = rCancelled.LookupHost(context.Background(), "test.go.dev")
+ if !errors.Is(err, context.Canceled) {
+ t.Errorf("errors.Is(err, context.Canceled) = false; want = true")
+ }
+
+ ctx, cancel := context.WithCancel(context.Background())
+ cancel()
+ _, err = goResolver.LookupHost(ctx, "text.go.dev")
+ if !errors.Is(err, context.Canceled) {
+ t.Errorf("errors.Is(err, context.Canceled) = false; want = true")
+ }
+}
diff --git a/go/src/net/lookup_unix.go b/go/src/net/lookup_unix.go
new file mode 100644
index 0000000000000000000000000000000000000000..86108939cd03d61dc5a52fb212dcc4508e7f89f6
--- /dev/null
+++ b/go/src/net/lookup_unix.go
@@ -0,0 +1,119 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || js || wasip1
+
+package net
+
+import (
+ "context"
+ "internal/bytealg"
+ "sync"
+)
+
+// readProtocolsOnce loads contents of /etc/protocols into protocols map
+// for quick access.
+var readProtocolsOnce = sync.OnceFunc(func() {
+ file, err := open("/etc/protocols")
+ if err != nil {
+ return
+ }
+ defer file.close()
+
+ for line, ok := file.readLine(); ok; line, ok = file.readLine() {
+ // tcp 6 TCP # transmission control protocol
+ if i := bytealg.IndexByteString(line, '#'); i >= 0 {
+ line = line[0:i]
+ }
+ f := getFields(line)
+ if len(f) < 2 {
+ continue
+ }
+ if proto, _, ok := dtoi(f[1]); ok {
+ if _, ok := protocols[f[0]]; !ok {
+ protocols[f[0]] = proto
+ }
+ for _, alias := range f[2:] {
+ if _, ok := protocols[alias]; !ok {
+ protocols[alias] = proto
+ }
+ }
+ }
+ }
+})
+
+// lookupProtocol looks up IP protocol name in /etc/protocols and
+// returns correspondent protocol number.
+func lookupProtocol(_ context.Context, name string) (int, error) {
+ readProtocolsOnce()
+ return lookupProtocolMap(name)
+}
+
+func (r *Resolver) lookupHost(ctx context.Context, host string) (addrs []string, err error) {
+ order, conf := systemConf().hostLookupOrder(r, host)
+ if order == hostLookupCgo {
+ return cgoLookupHost(ctx, host)
+ }
+ return r.goLookupHostOrder(ctx, host, order, conf)
+}
+
+func (r *Resolver) lookupIP(ctx context.Context, network, host string) (addrs []IPAddr, err error) {
+ order, conf := systemConf().hostLookupOrder(r, host)
+ if order == hostLookupCgo {
+ return cgoLookupIP(ctx, network, host)
+ }
+ ips, _, err := r.goLookupIPCNAMEOrder(ctx, network, host, order, conf)
+ return ips, err
+}
+
+func (r *Resolver) lookupPort(ctx context.Context, network, service string) (int, error) {
+ // Port lookup is not a DNS operation.
+ // Prefer the cgo resolver if possible.
+ if !systemConf().mustUseGoResolver(r) {
+ port, err := cgoLookupPort(ctx, network, service)
+ if err != nil {
+ // Issue 18213: if cgo fails, first check to see whether we
+ // have the answer baked-in to the net package.
+ if port, err := goLookupPort(network, service); err == nil {
+ return port, nil
+ }
+ }
+ return port, err
+ }
+ return goLookupPort(network, service)
+}
+
+func (r *Resolver) lookupCNAME(ctx context.Context, name string) (string, error) {
+ order, conf := systemConf().hostLookupOrder(r, name)
+ if order == hostLookupCgo {
+ if cname, err := cgoLookupCNAME(ctx, name); err == nil {
+ return cname, nil
+ }
+ }
+ return r.goLookupCNAME(ctx, name, order, conf)
+}
+
+func (r *Resolver) lookupSRV(ctx context.Context, service, proto, name string) (string, []*SRV, error) {
+ return r.goLookupSRV(ctx, service, proto, name)
+}
+
+func (r *Resolver) lookupMX(ctx context.Context, name string) ([]*MX, error) {
+ return r.goLookupMX(ctx, name)
+}
+
+func (r *Resolver) lookupNS(ctx context.Context, name string) ([]*NS, error) {
+ return r.goLookupNS(ctx, name)
+}
+
+func (r *Resolver) lookupTXT(ctx context.Context, name string) ([]string, error) {
+ return r.goLookupTXT(ctx, name)
+}
+
+func (r *Resolver) lookupAddr(ctx context.Context, addr string) ([]string, error) {
+ order, conf := systemConf().addrLookupOrder(r, addr)
+ if order == hostLookupCgo {
+ return cgoLookupPTR(ctx, addr)
+ }
+ return r.goLookupPTR(ctx, addr, order, conf)
+}
diff --git a/go/src/net/lookup_windows.go b/go/src/net/lookup_windows.go
new file mode 100644
index 0000000000000000000000000000000000000000..9af20bbb2bc1b008fb84b04e70fbfc4b23062b88
--- /dev/null
+++ b/go/src/net/lookup_windows.go
@@ -0,0 +1,479 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "context"
+ "internal/syscall/windows"
+ "os"
+ "runtime"
+ "syscall"
+ "time"
+ "unsafe"
+)
+
+// cgoAvailable set to true to indicate that the cgo resolver
+// is available on Windows. Note that on Windows the cgo resolver
+// does not actually use cgo.
+const cgoAvailable = true
+
+const (
+ _DNS_ERROR_RCODE_NAME_ERROR = syscall.Errno(9003)
+ _DNS_INFO_NO_RECORDS = syscall.Errno(9501)
+
+ _WSAHOST_NOT_FOUND = syscall.Errno(11001)
+ _WSATRY_AGAIN = syscall.Errno(11002)
+ _WSATYPE_NOT_FOUND = syscall.Errno(10109)
+)
+
+func winError(call string, err error) error {
+ switch err {
+ case _WSAHOST_NOT_FOUND, _DNS_ERROR_RCODE_NAME_ERROR, _DNS_INFO_NO_RECORDS:
+ return errNoSuchHost
+ }
+ return os.NewSyscallError(call, err)
+}
+
+func getprotobyname(name string) (proto int, err error) {
+ p, err := syscall.GetProtoByName(name)
+ if err != nil {
+ return 0, winError("getprotobyname", err)
+ }
+ return int(p.Proto), nil
+}
+
+// lookupProtocol looks up IP protocol name and returns correspondent protocol number.
+func lookupProtocol(ctx context.Context, name string) (int, error) {
+ // GetProtoByName return value is stored in thread local storage.
+ // Start new os thread before the call to prevent races.
+ type result struct {
+ proto int
+ err error
+ }
+ ch := make(chan result, 1) // buffer so that next goroutine never blocks
+ go func() {
+ if err := acquireThread(ctx); err != nil {
+ ch <- result{err: mapErr(err)}
+ return
+ }
+ defer releaseThread()
+ runtime.LockOSThread()
+ defer runtime.UnlockOSThread()
+ proto, err := getprotobyname(name)
+ ch <- result{proto: proto, err: err}
+ }()
+ select {
+ case r := <-ch:
+ if r.err != nil {
+ if proto, err := lookupProtocolMap(name); err == nil {
+ return proto, nil
+ }
+ r.err = newDNSError(r.err, name, "")
+ }
+ return r.proto, r.err
+ case <-ctx.Done():
+ return 0, newDNSError(mapErr(ctx.Err()), name, "")
+ }
+}
+
+func (r *Resolver) lookupHost(ctx context.Context, name string) ([]string, error) {
+ ips, err := r.lookupIP(ctx, "ip", name)
+ if err != nil {
+ return nil, err
+ }
+ addrs := make([]string, 0, len(ips))
+ for _, ip := range ips {
+ addrs = append(addrs, ip.String())
+ }
+ return addrs, nil
+}
+
+func (r *Resolver) lookupIP(ctx context.Context, network, name string) ([]IPAddr, error) {
+ if order, conf := systemConf().hostLookupOrder(r, name); order != hostLookupCgo {
+ return r.goLookupIP(ctx, network, name, order, conf)
+ }
+
+ // TODO(bradfitz,brainman): use ctx more. See TODO below.
+
+ var family int32 = syscall.AF_UNSPEC
+ switch ipVersion(network) {
+ case '4':
+ family = syscall.AF_INET
+ case '6':
+ family = syscall.AF_INET6
+ }
+
+ getaddr := func() ([]IPAddr, error) {
+ if err := acquireThread(ctx); err != nil {
+ return nil, newDNSError(mapErr(err), name, "")
+ }
+ defer releaseThread()
+ hints := syscall.AddrinfoW{
+ Family: family,
+ Socktype: syscall.SOCK_STREAM,
+ Protocol: syscall.IPPROTO_IP,
+ }
+ var result *syscall.AddrinfoW
+ name16p, err := syscall.UTF16PtrFromString(name)
+ if err != nil {
+ return nil, newDNSError(err, name, "")
+ }
+
+ dnsConf := getSystemDNSConfig()
+ start := time.Now()
+
+ var e error
+ for i := 0; i < dnsConf.attempts; i++ {
+ e = syscall.GetAddrInfoW(name16p, nil, &hints, &result)
+ if e == nil || e != _WSATRY_AGAIN || time.Since(start) > dnsConf.timeout {
+ break
+ }
+ }
+ if e != nil {
+ return nil, newDNSError(winError("getaddrinfow", e), name, "")
+ }
+ defer syscall.FreeAddrInfoW(result)
+ addrs := make([]IPAddr, 0, 5)
+ for ; result != nil; result = result.Next {
+ addr := unsafe.Pointer(result.Addr)
+ switch result.Family {
+ case syscall.AF_INET:
+ a := (*syscall.RawSockaddrInet4)(addr).Addr
+ addrs = append(addrs, IPAddr{IP: copyIP(a[:])})
+ case syscall.AF_INET6:
+ a := (*syscall.RawSockaddrInet6)(addr).Addr
+ zone := zoneCache.name(int((*syscall.RawSockaddrInet6)(addr).Scope_id))
+ addrs = append(addrs, IPAddr{IP: copyIP(a[:]), Zone: zone})
+ default:
+ return nil, newDNSError(syscall.EWINDOWS, name, "")
+ }
+ }
+ return addrs, nil
+ }
+
+ type ret struct {
+ addrs []IPAddr
+ err error
+ }
+
+ var ch chan ret
+ if ctx.Err() == nil {
+ ch = make(chan ret, 1)
+ go func() {
+ addr, err := getaddr()
+ ch <- ret{addrs: addr, err: err}
+ }()
+ }
+
+ select {
+ case r := <-ch:
+ return r.addrs, r.err
+ case <-ctx.Done():
+ // TODO(bradfitz,brainman): cancel the ongoing
+ // GetAddrInfoW? It would require conditionally using
+ // GetAddrInfoEx with lpOverlapped, which requires
+ // Windows 8 or newer. I guess we'll need oldLookupIP,
+ // newLookupIP, and newerLookUP.
+ //
+ // For now we just let it finish and write to the
+ // buffered channel.
+ return nil, newDNSError(mapErr(ctx.Err()), name, "")
+ }
+}
+
+func (r *Resolver) lookupPort(ctx context.Context, network, service string) (int, error) {
+ if systemConf().mustUseGoResolver(r) {
+ return lookupPortMap(network, service)
+ }
+
+ // TODO(bradfitz): finish ctx plumbing
+ if err := acquireThread(ctx); err != nil {
+ return 0, newDNSError(mapErr(err), network+"/"+service, "")
+ }
+ defer releaseThread()
+
+ var hints syscall.AddrinfoW
+
+ switch network {
+ case "ip": // no hints
+ case "tcp", "tcp4", "tcp6":
+ hints.Socktype = syscall.SOCK_STREAM
+ hints.Protocol = syscall.IPPROTO_TCP
+ case "udp", "udp4", "udp6":
+ hints.Socktype = syscall.SOCK_DGRAM
+ hints.Protocol = syscall.IPPROTO_UDP
+ default:
+ return 0, &DNSError{Err: "unknown network", Name: network + "/" + service}
+ }
+
+ switch ipVersion(network) {
+ case '4':
+ hints.Family = syscall.AF_INET
+ case '6':
+ hints.Family = syscall.AF_INET6
+ }
+
+ servicep, err := syscall.UTF16PtrFromString(service)
+ if err != nil {
+ return 0, newDNSError(err, network+"/"+service, "")
+ }
+
+ var result *syscall.AddrinfoW
+ e := syscall.GetAddrInfoW(nil, servicep, &hints, &result)
+ if e != nil {
+ if port, err := lookupPortMap(network, service); err == nil {
+ return port, nil
+ }
+
+ // The _WSATYPE_NOT_FOUND error is returned by GetAddrInfoW
+ // when the service name is unknown. We are also checking
+ // for _WSAHOST_NOT_FOUND here to match the cgo (unix) version
+ // cgo_unix.go (cgoLookupServicePort).
+ if e == _WSATYPE_NOT_FOUND || e == _WSAHOST_NOT_FOUND {
+ return 0, newDNSError(errUnknownPort, network+"/"+service, "")
+ }
+ return 0, newDNSError(winError("getaddrinfow", e), network+"/"+service, "")
+ }
+ defer syscall.FreeAddrInfoW(result)
+ if result == nil {
+ return 0, newDNSError(syscall.EINVAL, network+"/"+service, "")
+ }
+ addr := unsafe.Pointer(result.Addr)
+ switch result.Family {
+ case syscall.AF_INET:
+ a := (*syscall.RawSockaddrInet4)(addr)
+ return int(syscall.Ntohs(a.Port)), nil
+ case syscall.AF_INET6:
+ a := (*syscall.RawSockaddrInet6)(addr)
+ return int(syscall.Ntohs(a.Port)), nil
+ }
+ return 0, newDNSError(syscall.EINVAL, network+"/"+service, "")
+}
+
+func (r *Resolver) lookupCNAME(ctx context.Context, name string) (string, error) {
+ if order, conf := systemConf().hostLookupOrder(r, name); order != hostLookupCgo {
+ return r.goLookupCNAME(ctx, name, order, conf)
+ }
+
+ // TODO(bradfitz): finish ctx plumbing
+ if err := acquireThread(ctx); err != nil {
+ return "", newDNSError(mapErr(err), name, "")
+ }
+ defer releaseThread()
+ var rec *syscall.DNSRecord
+ e := syscall.DnsQuery(name, syscall.DNS_TYPE_CNAME, 0, nil, &rec, nil)
+ // windows returns DNS_INFO_NO_RECORDS if there are no CNAME-s
+ if errno, ok := e.(syscall.Errno); ok && errno == syscall.DNS_INFO_NO_RECORDS {
+ // if there are no aliases, the canonical name is the input name
+ return absDomainName(name), nil
+ }
+ if e != nil {
+ return "", newDNSError(winError("dnsquery", e), name, "")
+ }
+ defer syscall.DnsRecordListFree(rec, 1)
+
+ namep, err := syscall.UTF16PtrFromString(name)
+ if err != nil {
+ return "", newDNSError(err, name, "")
+ }
+
+ resolved := resolveCNAME(namep, rec)
+ cname := windows.UTF16PtrToString(resolved)
+ return absDomainName(cname), nil
+}
+
+func (r *Resolver) lookupSRV(ctx context.Context, service, proto, name string) (string, []*SRV, error) {
+ if systemConf().mustUseGoResolver(r) {
+ return r.goLookupSRV(ctx, service, proto, name)
+ }
+ // TODO(bradfitz): finish ctx plumbing
+ if err := acquireThread(ctx); err != nil {
+ return "", nil, newDNSError(mapErr(err), name, "")
+ }
+ defer releaseThread()
+ var target string
+ if service == "" && proto == "" {
+ target = name
+ } else {
+ target = "_" + service + "._" + proto + "." + name
+ }
+ var rec *syscall.DNSRecord
+ e := syscall.DnsQuery(target, syscall.DNS_TYPE_SRV, 0, nil, &rec, nil)
+ if e != nil {
+ return "", nil, newDNSError(winError("dnsquery", e), name, "")
+ }
+ defer syscall.DnsRecordListFree(rec, 1)
+
+ srvs := make([]*SRV, 0, 10)
+ for _, p := range validRecs(rec, syscall.DNS_TYPE_SRV, target) {
+ v := (*syscall.DNSSRVData)(unsafe.Pointer(&p.Data[0]))
+ srvs = append(srvs, &SRV{absDomainName(syscall.UTF16ToString((*[256]uint16)(unsafe.Pointer(v.Target))[:])), v.Port, v.Priority, v.Weight})
+ }
+ byPriorityWeight(srvs).sort()
+ return absDomainName(target), srvs, nil
+}
+
+func (r *Resolver) lookupMX(ctx context.Context, name string) ([]*MX, error) {
+ if systemConf().mustUseGoResolver(r) {
+ return r.goLookupMX(ctx, name)
+ }
+ // TODO(bradfitz): finish ctx plumbing.
+ if err := acquireThread(ctx); err != nil {
+ return nil, newDNSError(mapErr(err), name, "")
+ }
+ defer releaseThread()
+ var rec *syscall.DNSRecord
+ e := syscall.DnsQuery(name, syscall.DNS_TYPE_MX, 0, nil, &rec, nil)
+ if e != nil {
+ return nil, newDNSError(winError("dnsquery", e), name, "")
+ }
+ defer syscall.DnsRecordListFree(rec, 1)
+
+ mxs := make([]*MX, 0, 10)
+ for _, p := range validRecs(rec, syscall.DNS_TYPE_MX, name) {
+ v := (*syscall.DNSMXData)(unsafe.Pointer(&p.Data[0]))
+ mxs = append(mxs, &MX{absDomainName(windows.UTF16PtrToString(v.NameExchange)), v.Preference})
+ }
+ byPref(mxs).sort()
+ return mxs, nil
+}
+
+func (r *Resolver) lookupNS(ctx context.Context, name string) ([]*NS, error) {
+ if systemConf().mustUseGoResolver(r) {
+ return r.goLookupNS(ctx, name)
+ }
+ // TODO(bradfitz): finish ctx plumbing.
+ if err := acquireThread(ctx); err != nil {
+ return nil, newDNSError(mapErr(err), name, "")
+ }
+ defer releaseThread()
+ var rec *syscall.DNSRecord
+ e := syscall.DnsQuery(name, syscall.DNS_TYPE_NS, 0, nil, &rec, nil)
+ if e != nil {
+ return nil, newDNSError(winError("dnsquery", e), name, "")
+ }
+ defer syscall.DnsRecordListFree(rec, 1)
+
+ nss := make([]*NS, 0, 10)
+ for _, p := range validRecs(rec, syscall.DNS_TYPE_NS, name) {
+ v := (*syscall.DNSPTRData)(unsafe.Pointer(&p.Data[0]))
+ nss = append(nss, &NS{absDomainName(syscall.UTF16ToString((*[256]uint16)(unsafe.Pointer(v.Host))[:]))})
+ }
+ return nss, nil
+}
+
+func (r *Resolver) lookupTXT(ctx context.Context, name string) ([]string, error) {
+ if systemConf().mustUseGoResolver(r) {
+ return r.goLookupTXT(ctx, name)
+ }
+ // TODO(bradfitz): finish ctx plumbing.
+ if err := acquireThread(ctx); err != nil {
+ return nil, newDNSError(mapErr(err), name, "")
+ }
+ defer releaseThread()
+ var rec *syscall.DNSRecord
+ e := syscall.DnsQuery(name, syscall.DNS_TYPE_TEXT, 0, nil, &rec, nil)
+ if e != nil {
+ return nil, newDNSError(winError("dnsquery", e), name, "")
+ }
+ defer syscall.DnsRecordListFree(rec, 1)
+
+ txts := make([]string, 0, 10)
+ for _, p := range validRecs(rec, syscall.DNS_TYPE_TEXT, name) {
+ d := (*syscall.DNSTXTData)(unsafe.Pointer(&p.Data[0]))
+ s := ""
+ for _, v := range (*[1 << 10]*uint16)(unsafe.Pointer(&(d.StringArray[0])))[:d.StringCount:d.StringCount] {
+ s += windows.UTF16PtrToString(v)
+ }
+ txts = append(txts, s)
+ }
+ return txts, nil
+}
+
+func (r *Resolver) lookupAddr(ctx context.Context, addr string) ([]string, error) {
+ if order, conf := systemConf().addrLookupOrder(r, addr); order != hostLookupCgo {
+ return r.goLookupPTR(ctx, addr, order, conf)
+ }
+
+ // TODO(bradfitz): finish ctx plumbing.
+ if err := acquireThread(ctx); err != nil {
+ return nil, newDNSError(mapErr(err), addr, "")
+ }
+ defer releaseThread()
+ arpa, err := reverseaddr(addr)
+ if err != nil {
+ return nil, err
+ }
+ var rec *syscall.DNSRecord
+ e := syscall.DnsQuery(arpa, syscall.DNS_TYPE_PTR, 0, nil, &rec, nil)
+ if e != nil {
+ return nil, newDNSError(winError("dnsquery", e), addr, "")
+ }
+ defer syscall.DnsRecordListFree(rec, 1)
+
+ ptrs := make([]string, 0, 10)
+ for _, p := range validRecs(rec, syscall.DNS_TYPE_PTR, arpa) {
+ v := (*syscall.DNSPTRData)(unsafe.Pointer(&p.Data[0]))
+ ptrs = append(ptrs, absDomainName(windows.UTF16PtrToString(v.Host)))
+ }
+ return ptrs, nil
+}
+
+const dnsSectionMask = 0x0003
+
+// returns only results applicable to name and resolves CNAME entries.
+func validRecs(r *syscall.DNSRecord, dnstype uint16, name string) []*syscall.DNSRecord {
+ cname, err := syscall.UTF16PtrFromString(name)
+ if err != nil {
+ return nil
+ }
+ if dnstype != syscall.DNS_TYPE_CNAME {
+ cname = resolveCNAME(cname, r)
+ }
+ rec := make([]*syscall.DNSRecord, 0, 10)
+ for p := r; p != nil; p = p.Next {
+ // in case of a local machine, DNS records are returned with DNSREC_QUESTION flag instead of DNS_ANSWER
+ if p.Dw&dnsSectionMask != syscall.DnsSectionAnswer && p.Dw&dnsSectionMask != syscall.DnsSectionQuestion {
+ continue
+ }
+ if p.Type != dnstype {
+ continue
+ }
+ if !syscall.DnsNameCompare(cname, p.Name) {
+ continue
+ }
+ rec = append(rec, p)
+ }
+ return rec
+}
+
+// returns the last CNAME in chain.
+func resolveCNAME(name *uint16, r *syscall.DNSRecord) *uint16 {
+ // limit cname resolving to 10 in case of an infinite CNAME loop
+Cname:
+ for cnameloop := 0; cnameloop < 10; cnameloop++ {
+ for p := r; p != nil; p = p.Next {
+ if p.Dw&dnsSectionMask != syscall.DnsSectionAnswer {
+ continue
+ }
+ if p.Type != syscall.DNS_TYPE_CNAME {
+ continue
+ }
+ if !syscall.DnsNameCompare(name, p.Name) {
+ continue
+ }
+ name = (*syscall.DNSPTRData)(unsafe.Pointer(&r.Data[0])).Host
+ continue Cname
+ }
+ break
+ }
+ return name
+}
+
+// concurrentThreadsLimit returns the number of threads we permit to
+// run concurrently doing DNS lookups.
+func concurrentThreadsLimit() int {
+ return 500
+}
diff --git a/go/src/net/lookup_windows_test.go b/go/src/net/lookup_windows_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..bee1a6150c30d479867401c813574eab082ee6dc
--- /dev/null
+++ b/go/src/net/lookup_windows_test.go
@@ -0,0 +1,331 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "cmp"
+ "context"
+ "encoding/json"
+ "errors"
+ "fmt"
+ "internal/testenv"
+ "os/exec"
+ "reflect"
+ "regexp"
+ "slices"
+ "strings"
+ "syscall"
+ "testing"
+)
+
+var nslookupTestServers = []string{"mail.golang.com", "gmail.com"}
+var lookupTestIPs = []string{"8.8.8.8", "1.1.1.1"}
+
+func toJson(v any) string {
+ data, _ := json.Marshal(v)
+ return string(data)
+}
+
+func testLookup(t *testing.T, fn func(*testing.T, *Resolver, string)) {
+ for _, def := range []bool{true, false} {
+ for _, server := range nslookupTestServers {
+ var name string
+ if def {
+ name = "default/"
+ } else {
+ name = "go/"
+ }
+ t.Run(name+server, func(t *testing.T) {
+ t.Parallel()
+ r := DefaultResolver
+ if !def {
+ r = &Resolver{PreferGo: true}
+ }
+ fn(t, r, server)
+ })
+ }
+ }
+}
+
+func TestNSLookupMX(t *testing.T) {
+ testenv.MustHaveExternalNetwork(t)
+
+ testLookup(t, func(t *testing.T, r *Resolver, server string) {
+ mx, err := r.LookupMX(context.Background(), server)
+ if err != nil {
+ t.Fatal(err)
+ }
+ if len(mx) == 0 {
+ t.Fatal("no results")
+ }
+ expected, err := nslookupMX(server)
+ if err != nil {
+ t.Skipf("skipping failed nslookup %s test: %s", server, err)
+ }
+ byPrefAndHost := func(a, b *MX) int {
+ if r := cmp.Compare(a.Pref, b.Pref); r != 0 {
+ return r
+ }
+ return strings.Compare(a.Host, b.Host)
+ }
+ slices.SortFunc(expected, byPrefAndHost)
+ slices.SortFunc(mx, byPrefAndHost)
+ if !reflect.DeepEqual(expected, mx) {
+ t.Errorf("different results %s:\texp:%v\tgot:%v", server, toJson(expected), toJson(mx))
+ }
+ })
+}
+
+func TestNSLookupCNAME(t *testing.T) {
+ testenv.MustHaveExternalNetwork(t)
+
+ testLookup(t, func(t *testing.T, r *Resolver, server string) {
+ cname, err := r.LookupCNAME(context.Background(), server)
+ if err != nil {
+ t.Fatalf("failed %s: %s", server, err)
+ }
+ if cname == "" {
+ t.Fatalf("no result %s", server)
+ }
+ expected, err := nslookupCNAME(server)
+ if err != nil {
+ t.Skipf("skipping failed nslookup %s test: %s", server, err)
+ }
+ if expected != cname {
+ t.Errorf("different results %s:\texp:%v\tgot:%v", server, expected, cname)
+ }
+ })
+}
+
+func TestNSLookupNS(t *testing.T) {
+ testenv.MustHaveExternalNetwork(t)
+
+ testLookup(t, func(t *testing.T, r *Resolver, server string) {
+ ns, err := r.LookupNS(context.Background(), server)
+ if err != nil {
+ t.Fatalf("failed %s: %s", server, err)
+ }
+ if len(ns) == 0 {
+ t.Fatal("no results")
+ }
+ expected, err := nslookupNS(server)
+ if err != nil {
+ t.Skipf("skipping failed nslookup %s test: %s", server, err)
+ }
+ byHost := func(a, b *NS) int {
+ return strings.Compare(a.Host, b.Host)
+ }
+ slices.SortFunc(expected, byHost)
+ slices.SortFunc(ns, byHost)
+ if !reflect.DeepEqual(expected, ns) {
+ t.Errorf("different results %s:\texp:%v\tgot:%v", toJson(server), toJson(expected), ns)
+ }
+ })
+}
+
+func TestNSLookupTXT(t *testing.T) {
+ testenv.MustHaveExternalNetwork(t)
+
+ testLookup(t, func(t *testing.T, r *Resolver, server string) {
+ txt, err := r.LookupTXT(context.Background(), server)
+ if err != nil {
+ t.Fatalf("failed %s: %s", server, err)
+ }
+ if len(txt) == 0 {
+ t.Fatalf("no results")
+ }
+ expected, err := nslookupTXT(server)
+ if err != nil {
+ t.Skipf("skipping failed nslookup %s test: %s", server, err)
+ }
+ slices.Sort(expected)
+ slices.Sort(txt)
+ if !slices.Equal(expected, txt) {
+ t.Errorf("different results %s:\texp:%v\tgot:%v", server, toJson(expected), toJson(txt))
+ }
+ })
+}
+
+func TestLookupLocalPTR(t *testing.T) {
+ testenv.MustHaveExternalNetwork(t)
+
+ addr, err := localIP()
+ if err != nil {
+ t.Errorf("failed to get local ip: %s", err)
+ }
+ names, err := LookupAddr(addr.String())
+ if err != nil {
+ t.Errorf("failed %s: %s", addr, err)
+ }
+ if len(names) == 0 {
+ t.Errorf("no results")
+ }
+ expected, err := lookupPTR(addr.String())
+ if err != nil {
+ t.Skipf("skipping failed lookup %s test: %s", addr.String(), err)
+ }
+ slices.Sort(expected)
+ slices.Sort(names)
+ if !slices.Equal(expected, names) {
+ t.Errorf("different results %s:\texp:%v\tgot:%v", addr, toJson(expected), toJson(names))
+ }
+}
+
+func TestLookupPTR(t *testing.T) {
+ testenv.MustHaveExternalNetwork(t)
+
+ for _, addr := range lookupTestIPs {
+ names, err := LookupAddr(addr)
+ if err != nil {
+ // The DNSError type stores the error as a string, so it cannot wrap the
+ // original error code and we cannot check for it here. However, we can at
+ // least use its error string to identify the correct localized text for
+ // the error to skip.
+ var DNS_ERROR_RCODE_SERVER_FAILURE syscall.Errno = 9002
+ if strings.HasSuffix(err.Error(), DNS_ERROR_RCODE_SERVER_FAILURE.Error()) {
+ testenv.SkipFlaky(t, 38111)
+ }
+ t.Errorf("failed %s: %s", addr, err)
+ }
+ if len(names) == 0 {
+ t.Errorf("no results")
+ }
+ expected, err := lookupPTR(addr)
+ if err != nil {
+ t.Logf("skipping failed lookup %s test: %s", addr, err)
+ continue
+ }
+ slices.Sort(expected)
+ slices.Sort(names)
+ if !slices.Equal(expected, names) {
+ t.Errorf("different results %s:\texp:%v\tgot:%v", addr, toJson(expected), toJson(names))
+ }
+ }
+}
+
+func nslookup(qtype, name string) (string, error) {
+ var out strings.Builder
+ var err strings.Builder
+ cmd := exec.Command("nslookup", "-querytype="+qtype, name)
+ cmd.Stdout = &out
+ cmd.Stderr = &err
+ if err := cmd.Run(); err != nil {
+ return "", err
+ }
+ r := strings.ReplaceAll(out.String(), "\r\n", "\n")
+ // nslookup stderr output contains also debug information such as
+ // "Non-authoritative answer" and it doesn't return the correct errcode
+ if strings.Contains(err.String(), "can't find") {
+ return r, errors.New(err.String())
+ }
+ return r, nil
+}
+
+func nslookupMX(name string) (mx []*MX, err error) {
+ var r string
+ if r, err = nslookup("mx", name); err != nil {
+ return
+ }
+ mx = make([]*MX, 0, 10)
+ // linux nslookup syntax
+ // golang.org mail exchanger = 2 alt1.aspmx.l.google.com.
+ rx := regexp.MustCompile(`(?m)^([a-z0-9.\-]+)\s+mail exchanger\s*=\s*([0-9]+)\s*([a-z0-9.\-]+)$`)
+ for _, ans := range rx.FindAllStringSubmatch(r, -1) {
+ pref, _, _ := dtoi(ans[2])
+ mx = append(mx, &MX{absDomainName(ans[3]), uint16(pref)})
+ }
+ // windows nslookup syntax
+ // gmail.com MX preference = 30, mail exchanger = alt3.gmail-smtp-in.l.google.com
+ rx = regexp.MustCompile(`(?m)^([a-z0-9.\-]+)\s+MX preference\s*=\s*([0-9]+)\s*,\s*mail exchanger\s*=\s*([a-z0-9.\-]+)$`)
+ for _, ans := range rx.FindAllStringSubmatch(r, -1) {
+ pref, _, _ := dtoi(ans[2])
+ mx = append(mx, &MX{absDomainName(ans[3]), uint16(pref)})
+ }
+ return
+}
+
+func nslookupNS(name string) (ns []*NS, err error) {
+ var r string
+ if r, err = nslookup("ns", name); err != nil {
+ return
+ }
+ ns = make([]*NS, 0, 10)
+ // golang.org nameserver = ns1.google.com.
+ rx := regexp.MustCompile(`(?m)^([a-z0-9.\-]+)\s+nameserver\s*=\s*([a-z0-9.\-]+)$`)
+ for _, ans := range rx.FindAllStringSubmatch(r, -1) {
+ ns = append(ns, &NS{absDomainName(ans[2])})
+ }
+ return
+}
+
+func nslookupCNAME(name string) (cname string, err error) {
+ var r string
+ if r, err = nslookup("cname", name); err != nil {
+ return
+ }
+ // mail.golang.com canonical name = golang.org.
+ rx := regexp.MustCompile(`(?m)^([a-z0-9.\-]+)\s+canonical name\s*=\s*([a-z0-9.\-]+)$`)
+ // assumes the last CNAME is the correct one
+ last := name
+ for _, ans := range rx.FindAllStringSubmatch(r, -1) {
+ last = ans[2]
+ }
+ return absDomainName(last), nil
+}
+
+func nslookupTXT(name string) (txt []string, err error) {
+ var r string
+ if r, err = nslookup("txt", name); err != nil {
+ return
+ }
+ txt = make([]string, 0, 10)
+ // linux
+ // golang.org text = "v=spf1 redirect=_spf.google.com"
+
+ // windows
+ // golang.org text =
+ //
+ // "v=spf1 redirect=_spf.google.com"
+ rx := regexp.MustCompile(`(?m)^([a-z0-9.\-]+)\s+text\s*=\s*"(.*)"$`)
+ for _, ans := range rx.FindAllStringSubmatch(r, -1) {
+ txt = append(txt, ans[2])
+ }
+ return
+}
+
+func ping(name string) (string, error) {
+ cmd := exec.Command("ping", "-n", "1", "-a", name)
+ stdoutStderr, err := cmd.CombinedOutput()
+ if err != nil {
+ return "", fmt.Errorf("%v: %v", err, string(stdoutStderr))
+ }
+ r := strings.ReplaceAll(string(stdoutStderr), "\r\n", "\n")
+ return r, nil
+}
+
+func lookupPTR(name string) (ptr []string, err error) {
+ var r string
+ if r, err = ping(name); err != nil {
+ return
+ }
+ ptr = make([]string, 0, 10)
+ rx := regexp.MustCompile(`(?m)^Pinging\s+([a-zA-Z0-9.\-]+)\s+\[.*$`)
+ for _, ans := range rx.FindAllStringSubmatch(r, -1) {
+ ptr = append(ptr, absDomainName(ans[1]))
+ }
+ return
+}
+
+func localIP() (ip IP, err error) {
+ conn, err := Dial("udp", "golang.org:80")
+ if err != nil {
+ return nil, err
+ }
+ defer conn.Close()
+
+ localAddr := conn.LocalAddr().(*UDPAddr)
+
+ return localAddr.IP, nil
+}
diff --git a/go/src/net/mac.go b/go/src/net/mac.go
new file mode 100644
index 0000000000000000000000000000000000000000..b69a42d40b949d450bf1bc2c3b68c38f5ff00be7
--- /dev/null
+++ b/go/src/net/mac.go
@@ -0,0 +1,103 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+const hexDigit = "0123456789abcdef"
+
+// A HardwareAddr represents a physical hardware address.
+type HardwareAddr []byte
+
+func (a HardwareAddr) String() string {
+ if len(a) == 0 {
+ return ""
+ }
+ buf := make([]byte, 0, len(a)*3-1)
+ for i, b := range a {
+ if i > 0 {
+ buf = append(buf, ':')
+ }
+ buf = append(buf, hexDigit[b>>4])
+ buf = append(buf, hexDigit[b&0xF])
+ }
+ return string(buf)
+}
+
+// ParseMAC parses s as an IEEE 802 MAC-48, EUI-48, EUI-64, or a 20-octet
+// IP over InfiniBand link-layer address using one of the following formats:
+//
+// 00:00:5e:00:53:01
+// 02:00:5e:10:00:00:00:01
+// 00:00:00:00:fe:80:00:00:00:00:00:00:02:00:5e:10:00:00:00:01
+// 00-00-5e-00-53-01
+// 02-00-5e-10-00-00-00-01
+// 00-00-00-00-fe-80-00-00-00-00-00-00-02-00-5e-10-00-00-00-01
+// 0000.5e00.5301
+// 0200.5e10.0000.0001
+// 0000.0000.fe80.0000.0000.0000.0200.5e10.0000.0001
+// 00005e005301
+func ParseMAC(s string) (hw HardwareAddr, err error) {
+ if len(s) < 12 {
+ goto error
+ }
+
+ if s[2] == ':' || s[2] == '-' {
+ if (len(s)+1)%3 != 0 {
+ goto error
+ }
+ n := (len(s) + 1) / 3
+ if n != 6 && n != 8 && n != 20 {
+ goto error
+ }
+ hw = make(HardwareAddr, n)
+ for x, i := 0, 0; i < n; i++ {
+ var ok bool
+ if hw[i], ok = xtoi2(s[x:], s[2]); !ok {
+ goto error
+ }
+ x += 3
+ }
+ } else if s[4] == '.' {
+ if (len(s)+1)%5 != 0 {
+ goto error
+ }
+ n := 2 * (len(s) + 1) / 5
+ if n != 6 && n != 8 && n != 20 {
+ goto error
+ }
+ hw = make(HardwareAddr, n)
+ for x, i := 0, 0; i < n; i += 2 {
+ var ok bool
+ if hw[i], ok = xtoi2(s[x:x+2], 0); !ok {
+ goto error
+ }
+ if hw[i+1], ok = xtoi2(s[x+2:], s[4]); !ok {
+ goto error
+ }
+ x += 5
+ }
+ } else {
+ if len(s)%2 != 0 {
+ goto error
+ }
+
+ n := len(s) / 2
+ if n != 6 && n != 8 && n != 20 {
+ goto error
+ }
+
+ hw = make(HardwareAddr, len(s)/2)
+ for x, i := 0, 0; i < n; i++ {
+ var ok bool
+ if hw[i], ok = xtoi2(s[x:x+2], 0); !ok {
+ goto error
+ }
+ x += 2
+ }
+ }
+ return hw, nil
+
+error:
+ return nil, &AddrError{Err: "invalid MAC address", Addr: s}
+}
diff --git a/go/src/net/mac_test.go b/go/src/net/mac_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..9bfad4f12e806f0c003b6192a67859c09d930a72
--- /dev/null
+++ b/go/src/net/mac_test.go
@@ -0,0 +1,121 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "reflect"
+ "strings"
+ "testing"
+)
+
+var parseMACTests = []struct {
+ in string
+ out HardwareAddr
+ err string
+}{
+ // See RFC 7042, Section 2.1.1.
+ {"00:00:5e:00:53:01", HardwareAddr{0x00, 0x00, 0x5e, 0x00, 0x53, 0x01}, ""},
+ {"00-00-5e-00-53-01", HardwareAddr{0x00, 0x00, 0x5e, 0x00, 0x53, 0x01}, ""},
+ {"0000.5e00.5301", HardwareAddr{0x00, 0x00, 0x5e, 0x00, 0x53, 0x01}, ""},
+ {"00005e005301", HardwareAddr{0x00, 0x00, 0x5e, 0x00, 0x53, 0x01}, ""},
+
+ // See RFC 7042, Section 2.2.2.
+ {"02:00:5e:10:00:00:00:01", HardwareAddr{0x02, 0x00, 0x5e, 0x10, 0x00, 0x00, 0x00, 0x01}, ""},
+ {"02-00-5e-10-00-00-00-01", HardwareAddr{0x02, 0x00, 0x5e, 0x10, 0x00, 0x00, 0x00, 0x01}, ""},
+ {"0200.5e10.0000.0001", HardwareAddr{0x02, 0x00, 0x5e, 0x10, 0x00, 0x00, 0x00, 0x01}, ""},
+ {"02005e1000000001", HardwareAddr{0x02, 0x00, 0x5e, 0x10, 0x00, 0x00, 0x00, 0x01}, ""},
+
+ // See RFC 4391, Section 9.1.1.
+ {
+ "00:00:00:00:fe:80:00:00:00:00:00:00:02:00:5e:10:00:00:00:01",
+ HardwareAddr{
+ 0x00, 0x00, 0x00, 0x00,
+ 0xfe, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x02, 0x00, 0x5e, 0x10, 0x00, 0x00, 0x00, 0x01,
+ },
+ "",
+ },
+ {
+ "00-00-00-00-fe-80-00-00-00-00-00-00-02-00-5e-10-00-00-00-01",
+ HardwareAddr{
+ 0x00, 0x00, 0x00, 0x00,
+ 0xfe, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x02, 0x00, 0x5e, 0x10, 0x00, 0x00, 0x00, 0x01,
+ },
+ "",
+ },
+ {
+ "0000.0000.fe80.0000.0000.0000.0200.5e10.0000.0001",
+ HardwareAddr{
+ 0x00, 0x00, 0x00, 0x00,
+ 0xfe, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x02, 0x00, 0x5e, 0x10, 0x00, 0x00, 0x00, 0x01,
+ },
+ "",
+ },
+ {
+ "00000000fe8000000000000002005e1000000001",
+ HardwareAddr{
+ 0x00, 0x00, 0x00, 0x00,
+ 0xfe, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x02, 0x00, 0x5e, 0x10, 0x00, 0x00, 0x00, 0x01,
+ },
+ "",
+ },
+
+ {"ab:cd:ef:AB:CD:EF", HardwareAddr{0xab, 0xcd, 0xef, 0xab, 0xcd, 0xef}, ""},
+ {"ab:cd:ef:AB:CD:EF:ab:cd", HardwareAddr{0xab, 0xcd, 0xef, 0xab, 0xcd, 0xef, 0xab, 0xcd}, ""},
+ {
+ "ab:cd:ef:AB:CD:EF:ab:cd:ef:AB:CD:EF:ab:cd:ef:AB:CD:EF:ab:cd",
+ HardwareAddr{
+ 0xab, 0xcd, 0xef, 0xab,
+ 0xcd, 0xef, 0xab, 0xcd, 0xef, 0xab, 0xcd, 0xef,
+ 0xab, 0xcd, 0xef, 0xab, 0xcd, 0xef, 0xab, 0xcd,
+ },
+ "",
+ },
+
+ {"01.02.03.04.05.06", nil, "invalid MAC address"},
+ {"01:02:03:04:05:06:", nil, "invalid MAC address"},
+ {"x1:02:03:04:05:06", nil, "invalid MAC address"},
+ {"01002:03:04:05:06", nil, "invalid MAC address"},
+ {"01:02003:04:05:06", nil, "invalid MAC address"},
+ {"01:02:03004:05:06", nil, "invalid MAC address"},
+ {"01:02:03:04005:06", nil, "invalid MAC address"},
+ {"01:02:03:04:05006", nil, "invalid MAC address"},
+ {"01-02:03:04:05:06", nil, "invalid MAC address"},
+ {"01:02-03-04-05-06", nil, "invalid MAC address"},
+ {"0123:4567:89AF", nil, "invalid MAC address"},
+ {"0123-4567-89AF", nil, "invalid MAC address"},
+ {"0123456789AF0", nil, "invalid MAC address"},
+}
+
+func TestParseMAC(t *testing.T) {
+ match := func(err error, s string) bool {
+ if s == "" {
+ return err == nil
+ }
+ return err != nil && strings.Contains(err.Error(), s)
+ }
+
+ for i, tt := range parseMACTests {
+ out, err := ParseMAC(tt.in)
+ if !reflect.DeepEqual(out, tt.out) || !match(err, tt.err) {
+ t.Errorf("ParseMAC(%q) = %v, %v, want %v, %v", tt.in, out, err, tt.out, tt.err)
+ }
+ if tt.err == "" {
+ // Verify that serialization works too, and that it round-trips.
+ s := out.String()
+ out2, err := ParseMAC(s)
+ if err != nil {
+ t.Errorf("%d. ParseMAC(%q) = %v", i, s, err)
+ continue
+ }
+ if !reflect.DeepEqual(out2, out) {
+ t.Errorf("%d. ParseMAC(%q) = %v, want %v", i, s, out2, out)
+ }
+ }
+ }
+}
diff --git a/go/src/net/main_cloexec_test.go b/go/src/net/main_cloexec_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..6ea99ad6469cc954b8e4489554b37fdd269a3b2f
--- /dev/null
+++ b/go/src/net/main_cloexec_test.go
@@ -0,0 +1,27 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build dragonfly || freebsd || linux || netbsd || openbsd || solaris
+
+package net
+
+import "internal/poll"
+
+func init() {
+ extraTestHookInstallers = append(extraTestHookInstallers, installAccept4TestHook)
+ extraTestHookUninstallers = append(extraTestHookUninstallers, uninstallAccept4TestHook)
+}
+
+var (
+ // Placeholders for saving original socket system calls.
+ origAccept4 = poll.Accept4Func
+)
+
+func installAccept4TestHook() {
+ poll.Accept4Func = sw.Accept4
+}
+
+func uninstallAccept4TestHook() {
+ poll.Accept4Func = origAccept4
+}
diff --git a/go/src/net/main_conf_test.go b/go/src/net/main_conf_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..bb140240ed92c4fb813e54bbe2343e5462d9f05c
--- /dev/null
+++ b/go/src/net/main_conf_test.go
@@ -0,0 +1,97 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "context"
+ "runtime"
+ "testing"
+)
+
+func allResolvers(t *testing.T, f func(t *testing.T)) {
+ t.Run("default resolver", f)
+ t.Run("forced go resolver", func(t *testing.T) {
+ // On plan9 the forceGoDNS might not force the go resolver, currently
+ // it is only forced when the Resolver.Dial field is populated.
+ // See conf.go mustUseGoResolver.
+ defer forceGoDNS()()
+ f(t)
+ })
+ t.Run("forced cgo resolver", func(t *testing.T) {
+ defer forceCgoDNS()()
+ f(t)
+ })
+}
+
+// forceGoDNS forces the resolver configuration to use the pure Go resolver
+// and returns a fixup function to restore the old settings.
+func forceGoDNS() func() {
+ c := systemConf()
+ oldGo := c.netGo
+ oldCgo := c.netCgo
+ fixup := func() {
+ c.netGo = oldGo
+ c.netCgo = oldCgo
+ }
+ c.netGo = true
+ c.netCgo = false
+ return fixup
+}
+
+// forceCgoDNS forces the resolver configuration to use the cgo resolver
+// and returns a fixup function to restore the old settings.
+func forceCgoDNS() func() {
+ c := systemConf()
+ oldGo := c.netGo
+ oldCgo := c.netCgo
+ fixup := func() {
+ c.netGo = oldGo
+ c.netCgo = oldCgo
+ }
+ c.netGo = false
+ c.netCgo = true
+ return fixup
+}
+
+func TestForceCgoDNS(t *testing.T) {
+ if !cgoAvailable {
+ t.Skip("cgo resolver not available")
+ }
+ defer forceCgoDNS()()
+ order, _ := systemConf().hostLookupOrder(nil, "go.dev")
+ if order != hostLookupCgo {
+ t.Fatalf("hostLookupOrder returned: %v, want cgo", order)
+ }
+ order, _ = systemConf().addrLookupOrder(nil, "192.0.2.1")
+ if order != hostLookupCgo {
+ t.Fatalf("addrLookupOrder returned: %v, want cgo", order)
+ }
+ if systemConf().mustUseGoResolver(nil) {
+ t.Fatal("mustUseGoResolver = true, want false")
+ }
+}
+
+func TestForceGoDNS(t *testing.T) {
+ var resolver *Resolver
+ if runtime.GOOS == "plan9" {
+ resolver = &Resolver{
+ Dial: func(_ context.Context, _, _ string) (Conn, error) {
+ panic("unreachable")
+ },
+ }
+ }
+ defer forceGoDNS()()
+ order, _ := systemConf().hostLookupOrder(resolver, "go.dev")
+ if order == hostLookupCgo {
+ t.Fatalf("hostLookupOrder returned: %v, want go resolver order", order)
+ }
+ order, _ = systemConf().addrLookupOrder(resolver, "192.0.2.1")
+ if order == hostLookupCgo {
+ t.Fatalf("addrLookupOrder returned: %v, want go resolver order", order)
+ }
+ if !systemConf().mustUseGoResolver(resolver) {
+ t.Fatal("mustUseGoResolver = false, want true")
+ }
+}
diff --git a/go/src/net/main_plan9_test.go b/go/src/net/main_plan9_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..ca5f19adc149ac026fcc48f9c4e848991bfed822
--- /dev/null
+++ b/go/src/net/main_plan9_test.go
@@ -0,0 +1,20 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import "os/exec"
+
+func installTestHooks() {}
+
+func uninstallTestHooks() {}
+
+// forceCloseSockets must be called only from TestMain.
+func forceCloseSockets() {}
+
+func enableSocketConnect() {}
+
+func disableSocketConnect(network string) {}
+
+func addCmdInheritedHandle(cmd *exec.Cmd, fd uintptr) {}
diff --git a/go/src/net/main_posix_test.go b/go/src/net/main_posix_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..24a2a556605f738a6dd91705123a68832df49ac8
--- /dev/null
+++ b/go/src/net/main_posix_test.go
@@ -0,0 +1,50 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !plan9
+
+package net
+
+import (
+ "net/internal/socktest"
+ "strings"
+ "syscall"
+)
+
+func enableSocketConnect() {
+ sw.Set(socktest.FilterConnect, nil)
+}
+
+func disableSocketConnect(network string) {
+ net, _, _ := strings.Cut(network, ":")
+ sw.Set(socktest.FilterConnect, func(so *socktest.Status) (socktest.AfterFilter, error) {
+ switch net {
+ case "tcp4":
+ if so.Cookie.Family() == syscall.AF_INET && so.Cookie.Type() == syscall.SOCK_STREAM {
+ return nil, syscall.EHOSTUNREACH
+ }
+ case "udp4":
+ if so.Cookie.Family() == syscall.AF_INET && so.Cookie.Type() == syscall.SOCK_DGRAM {
+ return nil, syscall.EHOSTUNREACH
+ }
+ case "ip4":
+ if so.Cookie.Family() == syscall.AF_INET && so.Cookie.Type() == syscall.SOCK_RAW {
+ return nil, syscall.EHOSTUNREACH
+ }
+ case "tcp6":
+ if so.Cookie.Family() == syscall.AF_INET6 && so.Cookie.Type() == syscall.SOCK_STREAM {
+ return nil, syscall.EHOSTUNREACH
+ }
+ case "udp6":
+ if so.Cookie.Family() == syscall.AF_INET6 && so.Cookie.Type() == syscall.SOCK_DGRAM {
+ return nil, syscall.EHOSTUNREACH
+ }
+ case "ip6":
+ if so.Cookie.Family() == syscall.AF_INET6 && so.Cookie.Type() == syscall.SOCK_RAW {
+ return nil, syscall.EHOSTUNREACH
+ }
+ }
+ return nil, nil
+ })
+}
diff --git a/go/src/net/main_test.go b/go/src/net/main_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..66735962f103737846f6460cb8c89a9b3951f51c
--- /dev/null
+++ b/go/src/net/main_test.go
@@ -0,0 +1,222 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "flag"
+ "fmt"
+ "net/internal/socktest"
+ "os"
+ "runtime"
+ "slices"
+ "strings"
+ "sync"
+ "testing"
+ "time"
+)
+
+var (
+ sw socktest.Switch
+
+ // uninstallTestHooks runs just before a run of benchmarks.
+ testHookUninstaller sync.Once
+)
+
+var (
+ testTCPBig = flag.Bool("tcpbig", false, "whether to test massive size of data per read or write call on TCP connection")
+
+ testDNSFlood = flag.Bool("dnsflood", false, "whether to test DNS query flooding")
+
+ // If external IPv4 connectivity exists, we can try dialing
+ // non-node/interface local scope IPv4 addresses.
+ // On Windows, Lookup APIs may not return IPv4-related
+ // resource records when a node has no external IPv4
+ // connectivity.
+ testIPv4 = flag.Bool("ipv4", true, "assume external IPv4 connectivity exists")
+
+ // If external IPv6 connectivity exists, we can try dialing
+ // non-node/interface local scope IPv6 addresses.
+ // On Windows, Lookup APIs may not return IPv6-related
+ // resource records when a node has no external IPv6
+ // connectivity.
+ testIPv6 = flag.Bool("ipv6", false, "assume external IPv6 connectivity exists")
+)
+
+func TestMain(m *testing.M) {
+ setupTestData()
+ installTestHooks()
+
+ st := m.Run()
+
+ testHookUninstaller.Do(uninstallTestHooks)
+ if testing.Verbose() {
+ printRunningGoroutines()
+ printInflightSockets()
+ printSocketStats()
+ }
+ forceCloseSockets()
+ os.Exit(st)
+}
+
+// mustSetDeadline calls the bound method m to set a deadline on a Conn.
+// If the call fails, mustSetDeadline skips t if the current GOOS is believed
+// not to support deadlines, or fails the test otherwise.
+func mustSetDeadline(t testing.TB, m func(time.Time) error, d time.Duration) {
+ err := m(time.Now().Add(d))
+ if err != nil {
+ t.Helper()
+ if runtime.GOOS == "plan9" {
+ t.Skipf("skipping: %s does not support deadlines", runtime.GOOS)
+ }
+ t.Fatal(err)
+ }
+}
+
+type ipv6LinkLocalUnicastTest struct {
+ network, address string
+ nameLookup bool
+}
+
+var (
+ ipv6LinkLocalUnicastTCPTests []ipv6LinkLocalUnicastTest
+ ipv6LinkLocalUnicastUDPTests []ipv6LinkLocalUnicastTest
+)
+
+func setupTestData() {
+ if supportsIPv4() {
+ resolveTCPAddrTests = append(resolveTCPAddrTests, []resolveTCPAddrTest{
+ {"tcp", "localhost:1", &TCPAddr{IP: IPv4(127, 0, 0, 1), Port: 1}, nil},
+ {"tcp4", "localhost:2", &TCPAddr{IP: IPv4(127, 0, 0, 1), Port: 2}, nil},
+ }...)
+ resolveUDPAddrTests = append(resolveUDPAddrTests, []resolveUDPAddrTest{
+ {"udp", "localhost:1", &UDPAddr{IP: IPv4(127, 0, 0, 1), Port: 1}, nil},
+ {"udp4", "localhost:2", &UDPAddr{IP: IPv4(127, 0, 0, 1), Port: 2}, nil},
+ }...)
+ resolveIPAddrTests = append(resolveIPAddrTests, []resolveIPAddrTest{
+ {"ip", "localhost", &IPAddr{IP: IPv4(127, 0, 0, 1)}, nil},
+ {"ip4", "localhost", &IPAddr{IP: IPv4(127, 0, 0, 1)}, nil},
+ }...)
+ }
+
+ if supportsIPv6() {
+ resolveTCPAddrTests = append(resolveTCPAddrTests, resolveTCPAddrTest{"tcp6", "localhost:3", &TCPAddr{IP: IPv6loopback, Port: 3}, nil})
+ resolveUDPAddrTests = append(resolveUDPAddrTests, resolveUDPAddrTest{"udp6", "localhost:3", &UDPAddr{IP: IPv6loopback, Port: 3}, nil})
+ resolveIPAddrTests = append(resolveIPAddrTests, resolveIPAddrTest{"ip6", "localhost", &IPAddr{IP: IPv6loopback}, nil})
+
+ // Issue 20911: don't return IPv4 addresses for
+ // Resolve*Addr calls of the IPv6 unspecified address.
+ resolveTCPAddrTests = append(resolveTCPAddrTests, resolveTCPAddrTest{"tcp", "[::]:4", &TCPAddr{IP: IPv6unspecified, Port: 4}, nil})
+ resolveUDPAddrTests = append(resolveUDPAddrTests, resolveUDPAddrTest{"udp", "[::]:4", &UDPAddr{IP: IPv6unspecified, Port: 4}, nil})
+ resolveIPAddrTests = append(resolveIPAddrTests, resolveIPAddrTest{"ip", "::", &IPAddr{IP: IPv6unspecified}, nil})
+ }
+
+ ifi := loopbackInterface()
+ if ifi != nil {
+ index := fmt.Sprintf("%v", ifi.Index)
+ resolveTCPAddrTests = append(resolveTCPAddrTests, []resolveTCPAddrTest{
+ {"tcp6", "[fe80::1%" + ifi.Name + "]:1", &TCPAddr{IP: ParseIP("fe80::1"), Port: 1, Zone: zoneCache.name(ifi.Index)}, nil},
+ {"tcp6", "[fe80::1%" + index + "]:2", &TCPAddr{IP: ParseIP("fe80::1"), Port: 2, Zone: index}, nil},
+ }...)
+ resolveUDPAddrTests = append(resolveUDPAddrTests, []resolveUDPAddrTest{
+ {"udp6", "[fe80::1%" + ifi.Name + "]:1", &UDPAddr{IP: ParseIP("fe80::1"), Port: 1, Zone: zoneCache.name(ifi.Index)}, nil},
+ {"udp6", "[fe80::1%" + index + "]:2", &UDPAddr{IP: ParseIP("fe80::1"), Port: 2, Zone: index}, nil},
+ }...)
+ resolveIPAddrTests = append(resolveIPAddrTests, []resolveIPAddrTest{
+ {"ip6", "fe80::1%" + ifi.Name, &IPAddr{IP: ParseIP("fe80::1"), Zone: zoneCache.name(ifi.Index)}, nil},
+ {"ip6", "fe80::1%" + index, &IPAddr{IP: ParseIP("fe80::1"), Zone: index}, nil},
+ }...)
+ }
+
+ addr := ipv6LinkLocalUnicastAddr(ifi)
+ if addr != "" {
+ if runtime.GOOS != "dragonfly" {
+ ipv6LinkLocalUnicastTCPTests = append(ipv6LinkLocalUnicastTCPTests, []ipv6LinkLocalUnicastTest{
+ {"tcp", "[" + addr + "%" + ifi.Name + "]:0", false},
+ }...)
+ ipv6LinkLocalUnicastUDPTests = append(ipv6LinkLocalUnicastUDPTests, []ipv6LinkLocalUnicastTest{
+ {"udp", "[" + addr + "%" + ifi.Name + "]:0", false},
+ }...)
+ }
+ ipv6LinkLocalUnicastTCPTests = append(ipv6LinkLocalUnicastTCPTests, []ipv6LinkLocalUnicastTest{
+ {"tcp6", "[" + addr + "%" + ifi.Name + "]:0", false},
+ }...)
+ ipv6LinkLocalUnicastUDPTests = append(ipv6LinkLocalUnicastUDPTests, []ipv6LinkLocalUnicastTest{
+ {"udp6", "[" + addr + "%" + ifi.Name + "]:0", false},
+ }...)
+ switch runtime.GOOS {
+ case "darwin", "ios", "dragonfly", "freebsd", "openbsd", "netbsd":
+ ipv6LinkLocalUnicastTCPTests = append(ipv6LinkLocalUnicastTCPTests, []ipv6LinkLocalUnicastTest{
+ {"tcp", "[localhost%" + ifi.Name + "]:0", true},
+ {"tcp6", "[localhost%" + ifi.Name + "]:0", true},
+ }...)
+ ipv6LinkLocalUnicastUDPTests = append(ipv6LinkLocalUnicastUDPTests, []ipv6LinkLocalUnicastTest{
+ {"udp", "[localhost%" + ifi.Name + "]:0", true},
+ {"udp6", "[localhost%" + ifi.Name + "]:0", true},
+ }...)
+ case "linux":
+ ipv6LinkLocalUnicastTCPTests = append(ipv6LinkLocalUnicastTCPTests, []ipv6LinkLocalUnicastTest{
+ {"tcp", "[ip6-localhost%" + ifi.Name + "]:0", true},
+ {"tcp6", "[ip6-localhost%" + ifi.Name + "]:0", true},
+ }...)
+ ipv6LinkLocalUnicastUDPTests = append(ipv6LinkLocalUnicastUDPTests, []ipv6LinkLocalUnicastTest{
+ {"udp", "[ip6-localhost%" + ifi.Name + "]:0", true},
+ {"udp6", "[ip6-localhost%" + ifi.Name + "]:0", true},
+ }...)
+ }
+ }
+}
+
+func printRunningGoroutines() {
+ gss := runningGoroutines()
+ if len(gss) == 0 {
+ return
+ }
+ fmt.Fprintf(os.Stderr, "Running goroutines:\n")
+ for _, gs := range gss {
+ fmt.Fprintf(os.Stderr, "%v\n", gs)
+ }
+ fmt.Fprintf(os.Stderr, "\n")
+}
+
+// runningGoroutines returns a list of remaining goroutines.
+func runningGoroutines() []string {
+ var gss []string
+ b := make([]byte, 2<<20)
+ b = b[:runtime.Stack(b, true)]
+ for s := range strings.SplitSeq(string(b), "\n\n") {
+ _, stack, _ := strings.Cut(s, "\n")
+ stack = strings.TrimSpace(stack)
+ if !strings.Contains(stack, "created by net") {
+ continue
+ }
+ gss = append(gss, stack)
+ }
+ slices.Sort(gss)
+ return gss
+}
+
+func printInflightSockets() {
+ sos := sw.Sockets()
+ if len(sos) == 0 {
+ return
+ }
+ fmt.Fprintf(os.Stderr, "Inflight sockets:\n")
+ for s, so := range sos {
+ fmt.Fprintf(os.Stderr, "%v: %v\n", s, so)
+ }
+ fmt.Fprintf(os.Stderr, "\n")
+}
+
+func printSocketStats() {
+ sts := sw.Stats()
+ if len(sts) == 0 {
+ return
+ }
+ fmt.Fprintf(os.Stderr, "Socket statistical information:\n")
+ for _, st := range sts {
+ fmt.Fprintf(os.Stderr, "%v\n", st)
+ }
+ fmt.Fprintf(os.Stderr, "\n")
+}
diff --git a/go/src/net/main_unix_test.go b/go/src/net/main_unix_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..49d15b963e26301886211a10cab0212003735282
--- /dev/null
+++ b/go/src/net/main_unix_test.go
@@ -0,0 +1,60 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+package net
+
+import (
+ "internal/poll"
+ "os/exec"
+)
+
+var (
+ // Placeholders for saving original socket system calls.
+ origSocket = socketFunc
+ origClose = poll.CloseFunc
+ origConnect = connectFunc
+ origListen = listenFunc
+ origAccept = poll.AcceptFunc
+ origGetsockoptInt = getsockoptIntFunc
+
+ extraTestHookInstallers []func()
+ extraTestHookUninstallers []func()
+)
+
+func installTestHooks() {
+ socketFunc = sw.Socket
+ poll.CloseFunc = sw.Close
+ connectFunc = sw.Connect
+ listenFunc = sw.Listen
+ poll.AcceptFunc = sw.Accept
+ getsockoptIntFunc = sw.GetsockoptInt
+
+ for _, fn := range extraTestHookInstallers {
+ fn()
+ }
+}
+
+func uninstallTestHooks() {
+ socketFunc = origSocket
+ poll.CloseFunc = origClose
+ connectFunc = origConnect
+ listenFunc = origListen
+ poll.AcceptFunc = origAccept
+ getsockoptIntFunc = origGetsockoptInt
+
+ for _, fn := range extraTestHookUninstallers {
+ fn()
+ }
+}
+
+// forceCloseSockets must be called only from TestMain.
+func forceCloseSockets() {
+ for s := range sw.Sockets() {
+ poll.CloseFunc(s)
+ }
+}
+
+func addCmdInheritedHandle(cmd *exec.Cmd, fd uintptr) {}
diff --git a/go/src/net/main_wasm_test.go b/go/src/net/main_wasm_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..2dcfdabb3b444bc520b35cf79ef11389dc47eb52
--- /dev/null
+++ b/go/src/net/main_wasm_test.go
@@ -0,0 +1,17 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build wasip1 || js
+
+package net
+
+import "os/exec"
+
+func installTestHooks() {}
+
+func uninstallTestHooks() {}
+
+func forceCloseSockets() {}
+
+func addCmdInheritedHandle(cmd *exec.Cmd, fd uintptr) {}
diff --git a/go/src/net/main_windows_test.go b/go/src/net/main_windows_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..425030133535ca90c007e40c87f41ee496f2ad3f
--- /dev/null
+++ b/go/src/net/main_windows_test.go
@@ -0,0 +1,57 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "internal/poll"
+ "os/exec"
+ "syscall"
+)
+
+var (
+ // Placeholders for saving original socket system calls.
+ origWSASocket = wsaSocketFunc
+ origClosesocket = poll.CloseFunc
+ origConnect = connectFunc
+ origConnectEx = poll.ConnectExFunc
+ origListen = listenFunc
+ origAccept = poll.AcceptFunc
+)
+
+func installTestHooks() {
+ wsaSocketFunc = sw.WSASocket
+ poll.CloseFunc = sw.Closesocket
+ connectFunc = sw.Connect
+ poll.ConnectExFunc = sw.ConnectEx
+ listenFunc = sw.Listen
+ poll.AcceptFunc = sw.AcceptEx
+}
+
+func uninstallTestHooks() {
+ wsaSocketFunc = origWSASocket
+ poll.CloseFunc = origClosesocket
+ connectFunc = origConnect
+ poll.ConnectExFunc = origConnectEx
+ listenFunc = origListen
+ poll.AcceptFunc = origAccept
+}
+
+// forceCloseSockets must be called only from TestMain.
+func forceCloseSockets() {
+ for s := range sw.Sockets() {
+ poll.CloseFunc(s)
+ }
+}
+
+func addCmdInheritedHandle(cmd *exec.Cmd, fd uintptr) {
+ // Inherited handles are not inherited by default in Windows.
+ // We need to set the handle inheritance flag explicitly.
+ // See https://learn.microsoft.com/en-us/windows/win32/api/processthreadsapi/nf-processthreadsapi-createprocessa#parameters
+ // for more details.
+ if cmd.SysProcAttr == nil {
+ cmd.SysProcAttr = &syscall.SysProcAttr{}
+ }
+ cmd.SysProcAttr.AdditionalInheritedHandles = append(cmd.SysProcAttr.AdditionalInheritedHandles, syscall.Handle(fd))
+}
diff --git a/go/src/net/mockserver_test.go b/go/src/net/mockserver_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..66b8cbe40da5369c9722040446c5c63c03b83972
--- /dev/null
+++ b/go/src/net/mockserver_test.go
@@ -0,0 +1,645 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "context"
+ "errors"
+ "fmt"
+ "internal/testenv"
+ "log"
+ "os"
+ "path/filepath"
+ "runtime"
+ "strconv"
+ "sync"
+ "testing"
+ "time"
+)
+
+// testUnixAddr uses os.MkdirTemp to get a name that is unique.
+func testUnixAddr(t testing.TB) string {
+ // Pass an empty pattern to get a directory name that is as short as possible.
+ // If we end up with a name longer than the sun_path field in the sockaddr_un
+ // struct, we won't be able to make the syscall to open the socket.
+ d, err := os.MkdirTemp("", "")
+ if err != nil {
+ t.Fatal(err)
+ }
+ t.Cleanup(func() {
+ if err := os.RemoveAll(d); err != nil {
+ t.Error(err)
+ }
+ })
+ return filepath.Join(d, "sock")
+}
+
+func newLocalListener(t testing.TB, network string, lcOpt ...*ListenConfig) Listener {
+ var lc *ListenConfig
+ switch len(lcOpt) {
+ case 0:
+ lc = new(ListenConfig)
+ case 1:
+ lc = lcOpt[0]
+ default:
+ t.Helper()
+ t.Fatal("too many ListenConfigs passed to newLocalListener: want 0 or 1")
+ }
+
+ listen := func(net, addr string) Listener {
+ ln, err := lc.Listen(context.Background(), net, addr)
+ if err != nil {
+ t.Helper()
+ t.Fatal(err)
+ }
+ return ln
+ }
+
+ switch network {
+ case "tcp":
+ if supportsIPv4() {
+ return listen("tcp4", "127.0.0.1:0")
+ }
+ if supportsIPv6() {
+ return listen("tcp6", "[::1]:0")
+ }
+ case "tcp4":
+ if supportsIPv4() {
+ return listen("tcp4", "127.0.0.1:0")
+ }
+ case "tcp6":
+ if supportsIPv6() {
+ return listen("tcp6", "[::1]:0")
+ }
+ case "unix", "unixpacket":
+ return listen(network, testUnixAddr(t))
+ }
+
+ t.Helper()
+ t.Fatalf("%s is not supported", network)
+ return nil
+}
+
+func newDualStackListener() (lns []*TCPListener, err error) {
+ var args = []struct {
+ network string
+ TCPAddr
+ }{
+ {"tcp4", TCPAddr{IP: IPv4(127, 0, 0, 1)}},
+ {"tcp6", TCPAddr{IP: IPv6loopback}},
+ }
+ for i := 0; i < 64; i++ {
+ var port int
+ var lns []*TCPListener
+ for _, arg := range args {
+ arg.TCPAddr.Port = port
+ ln, err := ListenTCP(arg.network, &arg.TCPAddr)
+ if err != nil {
+ continue
+ }
+ port = ln.Addr().(*TCPAddr).Port
+ lns = append(lns, ln)
+ }
+ if len(lns) != len(args) {
+ for _, ln := range lns {
+ ln.Close()
+ }
+ continue
+ }
+ return lns, nil
+ }
+ return nil, errors.New("no dualstack port available")
+}
+
+type localServer struct {
+ lnmu sync.RWMutex
+ Listener
+ done chan bool // signal that indicates server stopped
+ cl []Conn // accepted connection list
+}
+
+func (ls *localServer) buildup(handler func(*localServer, Listener)) error {
+ go func() {
+ handler(ls, ls.Listener)
+ close(ls.done)
+ }()
+ return nil
+}
+
+func (ls *localServer) teardown() error {
+ ls.lnmu.Lock()
+ defer ls.lnmu.Unlock()
+ if ls.Listener != nil {
+ network := ls.Listener.Addr().Network()
+ address := ls.Listener.Addr().String()
+ ls.Listener.Close()
+ for _, c := range ls.cl {
+ if err := c.Close(); err != nil {
+ return err
+ }
+ }
+ <-ls.done
+ ls.Listener = nil
+ switch network {
+ case "unix", "unixpacket":
+ os.Remove(address)
+ }
+ }
+ return nil
+}
+
+func newLocalServer(t testing.TB, network string) *localServer {
+ t.Helper()
+ ln := newLocalListener(t, network)
+ return &localServer{Listener: ln, done: make(chan bool)}
+}
+
+type streamListener struct {
+ network, address string
+ Listener
+ done chan bool // signal that indicates server stopped
+}
+
+func (sl *streamListener) newLocalServer() *localServer {
+ return &localServer{Listener: sl.Listener, done: make(chan bool)}
+}
+
+type dualStackServer struct {
+ lnmu sync.RWMutex
+ lns []streamListener
+ port string
+
+ cmu sync.RWMutex
+ cs []Conn // established connections at the passive open side
+}
+
+func (dss *dualStackServer) buildup(handler func(*dualStackServer, Listener)) error {
+ for i := range dss.lns {
+ go func(i int) {
+ handler(dss, dss.lns[i].Listener)
+ close(dss.lns[i].done)
+ }(i)
+ }
+ return nil
+}
+
+func (dss *dualStackServer) teardownNetwork(network string) error {
+ dss.lnmu.Lock()
+ for i := range dss.lns {
+ if network == dss.lns[i].network && dss.lns[i].Listener != nil {
+ dss.lns[i].Listener.Close()
+ <-dss.lns[i].done
+ dss.lns[i].Listener = nil
+ }
+ }
+ dss.lnmu.Unlock()
+ return nil
+}
+
+func (dss *dualStackServer) teardown() error {
+ dss.lnmu.Lock()
+ for i := range dss.lns {
+ if dss.lns[i].Listener != nil {
+ dss.lns[i].Listener.Close()
+ <-dss.lns[i].done
+ }
+ }
+ dss.lns = dss.lns[:0]
+ dss.lnmu.Unlock()
+ dss.cmu.Lock()
+ for _, c := range dss.cs {
+ c.Close()
+ }
+ dss.cs = dss.cs[:0]
+ dss.cmu.Unlock()
+ return nil
+}
+
+func newDualStackServer() (*dualStackServer, error) {
+ lns, err := newDualStackListener()
+ if err != nil {
+ return nil, err
+ }
+ _, port, err := SplitHostPort(lns[0].Addr().String())
+ if err != nil {
+ lns[0].Close()
+ lns[1].Close()
+ return nil, err
+ }
+ return &dualStackServer{
+ lns: []streamListener{
+ {network: "tcp4", address: lns[0].Addr().String(), Listener: lns[0], done: make(chan bool)},
+ {network: "tcp6", address: lns[1].Addr().String(), Listener: lns[1], done: make(chan bool)},
+ },
+ port: port,
+ }, nil
+}
+
+func (ls *localServer) transponder(ln Listener, ch chan<- error) {
+ defer close(ch)
+
+ switch ln := ln.(type) {
+ case *TCPListener:
+ ln.SetDeadline(time.Now().Add(someTimeout))
+ case *UnixListener:
+ ln.SetDeadline(time.Now().Add(someTimeout))
+ }
+ c, err := ln.Accept()
+ if err != nil {
+ if perr := parseAcceptError(err); perr != nil {
+ ch <- perr
+ }
+ ch <- err
+ return
+ }
+ ls.cl = append(ls.cl, c)
+
+ network := ln.Addr().Network()
+ if c.LocalAddr().Network() != network || c.RemoteAddr().Network() != network {
+ ch <- fmt.Errorf("got %v->%v; expected %v->%v", c.LocalAddr().Network(), c.RemoteAddr().Network(), network, network)
+ return
+ }
+ c.SetDeadline(time.Now().Add(someTimeout))
+ c.SetReadDeadline(time.Now().Add(someTimeout))
+ c.SetWriteDeadline(time.Now().Add(someTimeout))
+
+ b := make([]byte, 256)
+ n, err := c.Read(b)
+ if err != nil {
+ if perr := parseReadError(err); perr != nil {
+ ch <- perr
+ }
+ ch <- err
+ return
+ }
+ if _, err := c.Write(b[:n]); err != nil {
+ if perr := parseWriteError(err); perr != nil {
+ ch <- perr
+ }
+ ch <- err
+ return
+ }
+}
+
+func transceiver(c Conn, wb []byte, ch chan<- error) {
+ defer close(ch)
+
+ c.SetDeadline(time.Now().Add(someTimeout))
+ c.SetReadDeadline(time.Now().Add(someTimeout))
+ c.SetWriteDeadline(time.Now().Add(someTimeout))
+
+ n, err := c.Write(wb)
+ if err != nil {
+ if perr := parseWriteError(err); perr != nil {
+ ch <- perr
+ }
+ ch <- err
+ return
+ }
+ if n != len(wb) {
+ ch <- fmt.Errorf("wrote %d; want %d", n, len(wb))
+ }
+ rb := make([]byte, len(wb))
+ n, err = c.Read(rb)
+ if err != nil {
+ if perr := parseReadError(err); perr != nil {
+ ch <- perr
+ }
+ ch <- err
+ return
+ }
+ if n != len(wb) {
+ ch <- fmt.Errorf("read %d; want %d", n, len(wb))
+ }
+}
+
+func newLocalPacketListener(t testing.TB, network string, lcOpt ...*ListenConfig) PacketConn {
+ var lc *ListenConfig
+ switch len(lcOpt) {
+ case 0:
+ lc = new(ListenConfig)
+ case 1:
+ lc = lcOpt[0]
+ default:
+ t.Helper()
+ t.Fatal("too many ListenConfigs passed to newLocalListener: want 0 or 1")
+ }
+
+ listenPacket := func(net, addr string) PacketConn {
+ c, err := lc.ListenPacket(context.Background(), net, addr)
+ if err != nil {
+ t.Helper()
+ t.Fatal(err)
+ }
+ return c
+ }
+
+ t.Helper()
+ switch network {
+ case "udp":
+ if supportsIPv4() {
+ return listenPacket("udp4", "127.0.0.1:0")
+ }
+ if supportsIPv6() {
+ return listenPacket("udp6", "[::1]:0")
+ }
+ case "udp4":
+ if supportsIPv4() {
+ return listenPacket("udp4", "127.0.0.1:0")
+ }
+ case "udp6":
+ if supportsIPv6() {
+ return listenPacket("udp6", "[::1]:0")
+ }
+ case "unixgram":
+ return listenPacket(network, testUnixAddr(t))
+ }
+
+ t.Fatalf("%s is not supported", network)
+ return nil
+}
+
+func newDualStackPacketListener() (cs []*UDPConn, err error) {
+ var args = []struct {
+ network string
+ UDPAddr
+ }{
+ {"udp4", UDPAddr{IP: IPv4(127, 0, 0, 1)}},
+ {"udp6", UDPAddr{IP: IPv6loopback}},
+ }
+ for i := 0; i < 64; i++ {
+ var port int
+ var cs []*UDPConn
+ for _, arg := range args {
+ arg.UDPAddr.Port = port
+ c, err := ListenUDP(arg.network, &arg.UDPAddr)
+ if err != nil {
+ continue
+ }
+ port = c.LocalAddr().(*UDPAddr).Port
+ cs = append(cs, c)
+ }
+ if len(cs) != len(args) {
+ for _, c := range cs {
+ c.Close()
+ }
+ continue
+ }
+ return cs, nil
+ }
+ return nil, errors.New("no dualstack port available")
+}
+
+type localPacketServer struct {
+ pcmu sync.RWMutex
+ PacketConn
+ done chan bool // signal that indicates server stopped
+}
+
+func (ls *localPacketServer) buildup(handler func(*localPacketServer, PacketConn)) error {
+ go func() {
+ handler(ls, ls.PacketConn)
+ close(ls.done)
+ }()
+ return nil
+}
+
+func (ls *localPacketServer) teardown() error {
+ ls.pcmu.Lock()
+ if ls.PacketConn != nil {
+ network := ls.PacketConn.LocalAddr().Network()
+ address := ls.PacketConn.LocalAddr().String()
+ ls.PacketConn.Close()
+ <-ls.done
+ ls.PacketConn = nil
+ switch network {
+ case "unixgram":
+ os.Remove(address)
+ }
+ }
+ ls.pcmu.Unlock()
+ return nil
+}
+
+func newLocalPacketServer(t testing.TB, network string) *localPacketServer {
+ t.Helper()
+ c := newLocalPacketListener(t, network)
+ return &localPacketServer{PacketConn: c, done: make(chan bool)}
+}
+
+type packetListener struct {
+ PacketConn
+}
+
+func (pl *packetListener) newLocalServer() *localPacketServer {
+ return &localPacketServer{PacketConn: pl.PacketConn, done: make(chan bool)}
+}
+
+func packetTransponder(c PacketConn, ch chan<- error) {
+ defer close(ch)
+
+ c.SetDeadline(time.Now().Add(someTimeout))
+ c.SetReadDeadline(time.Now().Add(someTimeout))
+ c.SetWriteDeadline(time.Now().Add(someTimeout))
+
+ b := make([]byte, 256)
+ n, peer, err := c.ReadFrom(b)
+ if err != nil {
+ if perr := parseReadError(err); perr != nil {
+ ch <- perr
+ }
+ ch <- err
+ return
+ }
+ if peer == nil { // for connected-mode sockets
+ switch c.LocalAddr().Network() {
+ case "udp":
+ peer, err = ResolveUDPAddr("udp", string(b[:n]))
+ case "unixgram":
+ peer, err = ResolveUnixAddr("unixgram", string(b[:n]))
+ }
+ if err != nil {
+ ch <- err
+ return
+ }
+ }
+ if _, err := c.WriteTo(b[:n], peer); err != nil {
+ if perr := parseWriteError(err); perr != nil {
+ ch <- perr
+ }
+ ch <- err
+ return
+ }
+}
+
+func packetTransceiver(c PacketConn, wb []byte, dst Addr, ch chan<- error) {
+ defer close(ch)
+
+ c.SetDeadline(time.Now().Add(someTimeout))
+ c.SetReadDeadline(time.Now().Add(someTimeout))
+ c.SetWriteDeadline(time.Now().Add(someTimeout))
+
+ n, err := c.WriteTo(wb, dst)
+ if err != nil {
+ if perr := parseWriteError(err); perr != nil {
+ ch <- perr
+ }
+ ch <- err
+ return
+ }
+ if n != len(wb) {
+ ch <- fmt.Errorf("wrote %d; want %d", n, len(wb))
+ }
+ rb := make([]byte, len(wb))
+ n, _, err = c.ReadFrom(rb)
+ if err != nil {
+ if perr := parseReadError(err); perr != nil {
+ ch <- perr
+ }
+ ch <- err
+ return
+ }
+ if n != len(wb) {
+ ch <- fmt.Errorf("read %d; want %d", n, len(wb))
+ }
+}
+
+func spawnTestSocketPair(t testing.TB, net string) (client, server Conn) {
+ t.Helper()
+
+ if !testableNetwork(net) {
+ t.Skipf("network %q not supported", net)
+ }
+
+ ln := newLocalListener(t, net)
+ defer ln.Close()
+ var cerr, serr error
+ acceptDone := make(chan struct{})
+ go func() {
+ server, serr = ln.Accept()
+ acceptDone <- struct{}{}
+ }()
+ client, cerr = Dial(ln.Addr().Network(), ln.Addr().String())
+ <-acceptDone
+ if cerr != nil {
+ if server != nil {
+ server.Close()
+ }
+ t.Fatal(cerr)
+ }
+ if serr != nil {
+ if client != nil {
+ client.Close()
+ }
+ t.Fatal(serr)
+ }
+ return client, server
+}
+
+func startTestSocketPeer(t testing.TB, conn Conn, op string, chunkSize, totalSize int) (func(t testing.TB), error) {
+ t.Helper()
+ f, err := conn.(interface{ File() (*os.File, error) }).File()
+ if err != nil {
+ return nil, err
+ }
+
+ cmd := testenv.Command(t, testenv.Executable(t))
+ cmd.Env = []string{
+ "GO_NET_TEST_TRANSFER=1",
+ "GO_NET_TEST_TRANSFER_OP=" + op,
+ "GO_NET_TEST_TRANSFER_CHUNK_SIZE=" + strconv.Itoa(chunkSize),
+ "GO_NET_TEST_TRANSFER_TOTAL_SIZE=" + strconv.Itoa(totalSize),
+ "TMPDIR=" + os.Getenv("TMPDIR"),
+ }
+ if runtime.GOOS == "windows" {
+ // Windows doesn't support ExtraFiles
+ fd := f.Fd()
+ cmd.Env = append(cmd.Env, "GO_NET_TEST_TRANSFER_FD="+strconv.FormatUint(uint64(fd), 10))
+ addCmdInheritedHandle(cmd, fd)
+ } else {
+ cmd.ExtraFiles = append(cmd.ExtraFiles, f)
+ }
+ cmd.Stdout = os.Stdout
+ cmd.Stderr = os.Stderr
+
+ if err := cmd.Start(); err != nil {
+ return nil, err
+ }
+
+ cmdCh := make(chan error, 1)
+ go func() {
+ err := cmd.Wait()
+ conn.Close()
+ f.Close()
+ cmdCh <- err
+ }()
+
+ return func(tb testing.TB) {
+ err := <-cmdCh
+ if err != nil {
+ tb.Errorf("process exited with error: %v", err)
+ }
+ }, nil
+}
+
+func init() {
+ if os.Getenv("GO_NET_TEST_TRANSFER") == "" {
+ return
+ }
+ defer os.Exit(0)
+
+ var fd uintptr
+ if runtime.GOOS == "windows" {
+ v, err := strconv.ParseUint(os.Getenv("GO_NET_TEST_TRANSFER_FD"), 10, 0)
+ if err != nil {
+ log.Fatal(err)
+ }
+ fd = uintptr(v)
+ } else {
+ fd = uintptr(3)
+ }
+ f := os.NewFile(fd, "splice-test-conn")
+ defer f.Close()
+
+ conn, err := FileConn(f)
+ if err != nil {
+ log.Fatal(err)
+ }
+
+ var chunkSize int
+ if chunkSize, err = strconv.Atoi(os.Getenv("GO_NET_TEST_TRANSFER_CHUNK_SIZE")); err != nil {
+ log.Fatal(err)
+ }
+ buf := make([]byte, chunkSize)
+
+ var totalSize int
+ if totalSize, err = strconv.Atoi(os.Getenv("GO_NET_TEST_TRANSFER_TOTAL_SIZE")); err != nil {
+ log.Fatal(err)
+ }
+
+ var fn func([]byte) (int, error)
+ switch op := os.Getenv("GO_NET_TEST_TRANSFER_OP"); op {
+ case "r":
+ fn = conn.Read
+ case "w":
+ defer conn.Close()
+
+ fn = conn.Write
+ default:
+ log.Fatalf("unknown op %q", op)
+ }
+
+ var n int
+ for count := 0; count < totalSize; count += n {
+ if count+chunkSize > totalSize {
+ buf = buf[:totalSize-count]
+ }
+
+ var err error
+ if n, err = fn(buf); err != nil {
+ return
+ }
+ }
+}
diff --git a/go/src/net/mptcpsock_linux.go b/go/src/net/mptcpsock_linux.go
new file mode 100644
index 0000000000000000000000000000000000000000..5b58418653fbf51cdc68024b1302106bd6a9e38c
--- /dev/null
+++ b/go/src/net/mptcpsock_linux.go
@@ -0,0 +1,137 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "context"
+ "errors"
+ "internal/poll"
+ "internal/syscall/unix"
+ "sync"
+ "syscall"
+)
+
+var (
+ mptcpOnce sync.Once
+ mptcpAvailable bool
+ hasSOLMPTCP bool // only valid if mptcpAvailable is true
+)
+
+// These constants aren't in the syscall package, which is frozen
+const (
+ _IPPROTO_MPTCP = 0x106
+ _SOL_MPTCP = 0x11c
+ _MPTCP_INFO = 0x1
+)
+
+func supportsMultipathTCP() bool {
+ mptcpOnce.Do(initMPTCPavailable)
+ return mptcpAvailable
+}
+
+// Check that MPTCP is supported by attempting to create an MPTCP socket and by
+// looking at the returned error if any.
+func initMPTCPavailable() {
+ family := syscall.AF_INET
+ if !supportsIPv4() {
+ family = syscall.AF_INET6
+ }
+ s, err := sysSocket(family, syscall.SOCK_STREAM, _IPPROTO_MPTCP)
+
+ switch {
+ case errors.Is(err, syscall.EPROTONOSUPPORT): // Not supported: >= v5.6
+ return
+ case errors.Is(err, syscall.EINVAL): // Not supported: < v5.6
+ return
+ case err == nil: // Supported and no error
+ poll.CloseFunc(s)
+ fallthrough
+ default:
+ // another error: MPTCP was not available but it might be later
+ mptcpAvailable = true
+ }
+
+ // SOL_MPTCP only supported from kernel 5.16.
+ hasSOLMPTCP = unix.KernelVersionGE(5, 16)
+}
+
+func (sd *sysDialer) dialMPTCP(ctx context.Context, laddr, raddr *TCPAddr) (*TCPConn, error) {
+ if supportsMultipathTCP() {
+ if conn, err := sd.doDialTCPProto(ctx, laddr, raddr, _IPPROTO_MPTCP); err == nil {
+ return conn, nil
+ }
+ }
+
+ // Fallback to dialTCP if Multipath TCP isn't supported on this operating
+ // system. But also fallback in case of any error with MPTCP.
+ //
+ // Possible MPTCP specific error: ENOPROTOOPT (sysctl net.mptcp.enabled=0)
+ // But just in case MPTCP is blocked differently (SELinux, etc.), just
+ // retry with "plain" TCP.
+ return sd.dialTCP(ctx, laddr, raddr)
+}
+
+func (sl *sysListener) listenMPTCP(ctx context.Context, laddr *TCPAddr) (*TCPListener, error) {
+ if supportsMultipathTCP() {
+ if dial, err := sl.listenTCPProto(ctx, laddr, _IPPROTO_MPTCP); err == nil {
+ return dial, nil
+ }
+ }
+
+ // Fallback to listenTCP if Multipath TCP isn't supported on this operating
+ // system. But also fallback in case of any error with MPTCP.
+ //
+ // Possible MPTCP specific error: ENOPROTOOPT (sysctl net.mptcp.enabled=0)
+ // But just in case MPTCP is blocked differently (SELinux, etc.), just
+ // retry with "plain" TCP.
+ return sl.listenTCP(ctx, laddr)
+}
+
+// hasFallenBack reports whether the MPTCP connection has fallen back to "plain"
+// TCP.
+//
+// A connection can fallback to TCP for different reasons, e.g. the other peer
+// doesn't support it, a middle box "accidentally" drops the option, etc.
+//
+// If the MPTCP protocol has not been requested when creating the socket, this
+// method will return true: MPTCP is not being used.
+//
+// Kernel >= 5.16 returns EOPNOTSUPP/ENOPROTOOPT in case of fallback.
+// Older kernels will always return them even if MPTCP is used: not usable.
+func hasFallenBack(fd *netFD) bool {
+ _, err := fd.pfd.GetsockoptInt(_SOL_MPTCP, _MPTCP_INFO)
+
+ // 2 expected errors in case of fallback depending on the address family
+ // - AF_INET: EOPNOTSUPP
+ // - AF_INET6: ENOPROTOOPT
+ return err == syscall.EOPNOTSUPP || err == syscall.ENOPROTOOPT
+}
+
+// isUsingMPTCPProto reports whether the socket protocol is MPTCP.
+//
+// Compared to hasFallenBack method, here only the socket protocol being used is
+// checked: it can be MPTCP but it doesn't mean MPTCP is used on the wire, maybe
+// a fallback to TCP has been done.
+func isUsingMPTCPProto(fd *netFD) bool {
+ proto, _ := fd.pfd.GetsockoptInt(syscall.SOL_SOCKET, syscall.SO_PROTOCOL)
+
+ return proto == _IPPROTO_MPTCP
+}
+
+// isUsingMultipathTCP reports whether MPTCP is still being used.
+//
+// Please look at the description of hasFallenBack (kernel >=5.16) and
+// isUsingMPTCPProto methods for more details about what is being checked here.
+func isUsingMultipathTCP(fd *netFD) bool {
+ if !supportsMultipathTCP() {
+ return false
+ }
+
+ if hasSOLMPTCP {
+ return !hasFallenBack(fd)
+ }
+
+ return isUsingMPTCPProto(fd)
+}
diff --git a/go/src/net/mptcpsock_linux_test.go b/go/src/net/mptcpsock_linux_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..5134aba75eabb5d36e168fa1c5733ae7a01f6695
--- /dev/null
+++ b/go/src/net/mptcpsock_linux_test.go
@@ -0,0 +1,192 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "bytes"
+ "context"
+ "errors"
+ "syscall"
+ "testing"
+)
+
+func newLocalListenerMPTCP(t *testing.T, envVar bool) Listener {
+ lc := &ListenConfig{}
+
+ if envVar {
+ if !lc.MultipathTCP() {
+ t.Fatal("MultipathTCP Listen is not on despite GODEBUG=multipathtcp=1")
+ }
+ } else {
+ if lc.MultipathTCP() {
+ t.Error("MultipathTCP should be off by default")
+ }
+
+ lc.SetMultipathTCP(true)
+ if !lc.MultipathTCP() {
+ t.Fatal("MultipathTCP is not on after having been forced to on")
+ }
+ }
+
+ ln, err := lc.Listen(context.Background(), "tcp", "127.0.0.1:0")
+ if err != nil {
+ t.Fatal(err)
+ }
+ return ln
+}
+
+func postAcceptMPTCP(ls *localServer, ch chan<- error) {
+ defer close(ch)
+
+ if len(ls.cl) == 0 {
+ ch <- errors.New("no accepted stream")
+ return
+ }
+
+ c := ls.cl[0]
+
+ tcp, ok := c.(*TCPConn)
+ if !ok {
+ ch <- errors.New("struct is not a TCPConn")
+ return
+ }
+
+ mptcp, err := tcp.MultipathTCP()
+ if err != nil {
+ ch <- err
+ return
+ }
+
+ if !mptcp {
+ ch <- errors.New("incoming connection is not with MPTCP")
+ return
+ }
+
+ // Also check the method for the older kernels if not tested before
+ if hasSOLMPTCP && !isUsingMPTCPProto(tcp.fd) {
+ ch <- errors.New("incoming connection is not an MPTCP proto")
+ return
+ }
+}
+
+func dialerMPTCP(t *testing.T, addr string, envVar bool) {
+ d := &Dialer{}
+
+ if envVar {
+ if !d.MultipathTCP() {
+ t.Fatal("MultipathTCP Dialer is not on despite GODEBUG=multipathtcp=1")
+ }
+ } else {
+ if d.MultipathTCP() {
+ t.Error("MultipathTCP should be off by default")
+ }
+
+ d.SetMultipathTCP(true)
+ if !d.MultipathTCP() {
+ t.Fatal("MultipathTCP is not on after having been forced to on")
+ }
+ }
+
+ c, err := d.Dial("tcp", addr)
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer c.Close()
+
+ tcp, ok := c.(*TCPConn)
+ if !ok {
+ t.Fatal("struct is not a TCPConn")
+ }
+
+ // Transfer a bit of data to make sure everything is still OK
+ snt := []byte("MPTCP TEST")
+ if _, err := c.Write(snt); err != nil {
+ t.Fatal(err)
+ }
+ b := make([]byte, len(snt))
+ if _, err := c.Read(b); err != nil {
+ t.Fatal(err)
+ }
+ if !bytes.Equal(snt, b) {
+ t.Errorf("sent bytes (%s) are different from received ones (%s)", snt, b)
+ }
+
+ mptcp, err := tcp.MultipathTCP()
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ t.Logf("outgoing connection from %s with mptcp: %t", addr, mptcp)
+
+ if !mptcp {
+ t.Error("outgoing connection is not with MPTCP")
+ }
+
+ // Also check the method for the older kernels if not tested before
+ if hasSOLMPTCP && !isUsingMPTCPProto(tcp.fd) {
+ t.Error("outgoing connection is not an MPTCP proto")
+ }
+}
+
+func canCreateMPTCPSocket() bool {
+ // We want to know if we can create an MPTCP socket, not just if it is
+ // available (mptcpAvailable()): it could be blocked by the admin
+ fd, err := syscall.Socket(syscall.AF_INET, syscall.SOCK_STREAM, _IPPROTO_MPTCP)
+ if err != nil {
+ return false
+ }
+
+ syscall.Close(fd)
+ return true
+}
+
+func testMultiPathTCP(t *testing.T, envVar bool) {
+ if envVar {
+ t.Log("Test with GODEBUG=multipathtcp=1")
+ t.Setenv("GODEBUG", "multipathtcp=1")
+ } else {
+ t.Log("Test with GODEBUG=multipathtcp=0")
+ t.Setenv("GODEBUG", "multipathtcp=0")
+ }
+
+ ln := newLocalListenerMPTCP(t, envVar)
+
+ // similar to tcpsock_test:TestIPv6LinkLocalUnicastTCP
+ ls := (&streamListener{Listener: ln}).newLocalServer()
+ defer ls.teardown()
+
+ if g, w := ls.Listener.Addr().Network(), "tcp"; g != w {
+ t.Fatalf("Network type mismatch: got %q, want %q", g, w)
+ }
+
+ genericCh := make(chan error)
+ mptcpCh := make(chan error)
+ handler := func(ls *localServer, ln Listener) {
+ ls.transponder(ln, genericCh)
+ postAcceptMPTCP(ls, mptcpCh)
+ }
+ if err := ls.buildup(handler); err != nil {
+ t.Fatal(err)
+ }
+
+ dialerMPTCP(t, ln.Addr().String(), envVar)
+
+ if err := <-genericCh; err != nil {
+ t.Error(err)
+ }
+ if err := <-mptcpCh; err != nil {
+ t.Error(err)
+ }
+}
+
+func TestMultiPathTCP(t *testing.T) {
+ if !canCreateMPTCPSocket() {
+ t.Skip("Cannot create MPTCP sockets")
+ }
+
+ for _, envVar := range []bool{false, true} {
+ testMultiPathTCP(t, envVar)
+ }
+}
diff --git a/go/src/net/mptcpsock_stub.go b/go/src/net/mptcpsock_stub.go
new file mode 100644
index 0000000000000000000000000000000000000000..458c1530d75d6c80fcab2ef0767a3451cd084692
--- /dev/null
+++ b/go/src/net/mptcpsock_stub.go
@@ -0,0 +1,23 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !linux
+
+package net
+
+import (
+ "context"
+)
+
+func (sd *sysDialer) dialMPTCP(ctx context.Context, laddr, raddr *TCPAddr) (*TCPConn, error) {
+ return sd.dialTCP(ctx, laddr, raddr)
+}
+
+func (sl *sysListener) listenMPTCP(ctx context.Context, laddr *TCPAddr) (*TCPListener, error) {
+ return sl.listenTCP(ctx, laddr)
+}
+
+func isUsingMultipathTCP(fd *netFD) bool {
+ return false
+}
diff --git a/go/src/net/net.go b/go/src/net/net.go
new file mode 100644
index 0000000000000000000000000000000000000000..72f5772155098290391aa58cf03e084a3af72fbb
--- /dev/null
+++ b/go/src/net/net.go
@@ -0,0 +1,897 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package net provides a portable interface for network I/O, including
+TCP/IP, UDP, domain name resolution, and Unix domain sockets.
+
+Although the package provides access to low-level networking
+primitives, most clients will need only the basic interface provided
+by the [Dial], [Listen], and Accept functions and the associated
+[Conn] and [Listener] interfaces. The crypto/tls package uses
+the same interfaces and similar Dial and Listen functions.
+
+The Dial function connects to a server:
+
+ conn, err := net.Dial("tcp", "golang.org:80")
+ if err != nil {
+ // handle error
+ }
+ fmt.Fprintf(conn, "GET / HTTP/1.0\r\n\r\n")
+ status, err := bufio.NewReader(conn).ReadString('\n')
+ // ...
+
+The Listen function creates servers:
+
+ ln, err := net.Listen("tcp", ":8080")
+ if err != nil {
+ // handle error
+ }
+ for {
+ conn, err := ln.Accept()
+ if err != nil {
+ // handle error
+ }
+ go handleConnection(conn)
+ }
+
+# Name Resolution
+
+The method for resolving domain names, whether indirectly with functions like Dial
+or directly with functions like [LookupHost] and [LookupAddr], varies by operating system.
+
+On Unix systems, the resolver has two options for resolving names.
+It can use a pure Go resolver that sends DNS requests directly to the servers
+listed in /etc/resolv.conf, or it can use a cgo-based resolver that calls C
+library routines such as getaddrinfo and getnameinfo.
+
+On Unix the pure Go resolver is preferred over the cgo resolver, because a blocked DNS
+request consumes only a goroutine, while a blocked C call consumes an operating system thread.
+When cgo is available, the cgo-based resolver is used instead under a variety of
+conditions: on systems that do not let programs make direct DNS requests (OS X),
+when the LOCALDOMAIN environment variable is present (even if empty),
+when the RES_OPTIONS or HOSTALIASES environment variable is non-empty,
+when the ASR_CONFIG environment variable is non-empty (OpenBSD only),
+when /etc/resolv.conf or /etc/nsswitch.conf specify the use of features that the
+Go resolver does not implement.
+
+On all systems (except Plan 9), when the cgo resolver is being used
+this package applies a concurrent cgo lookup limit to prevent the system
+from running out of system threads. Currently, it is limited to 500 concurrent lookups.
+
+The resolver decision can be overridden by setting the netdns value of the
+GODEBUG environment variable (see package runtime) to go or cgo, as in:
+
+ export GODEBUG=netdns=go # force pure Go resolver
+ export GODEBUG=netdns=cgo # force native resolver (cgo, win32)
+
+The decision can also be forced while building the Go source tree
+by setting the netgo or netcgo build tag.
+The netgo build tag disables entirely the use of the native (CGO) resolver,
+meaning the Go resolver is the only one that can be used.
+With the netcgo build tag the native and the pure Go resolver are compiled into the binary,
+but the native (CGO) resolver is preferred over the Go resolver.
+With netcgo, the Go resolver can still be forced at runtime with GODEBUG=netdns=go.
+
+A numeric netdns setting, as in GODEBUG=netdns=1, causes the resolver
+to print debugging information about its decisions.
+To force a particular resolver while also printing debugging information,
+join the two settings by a plus sign, as in GODEBUG=netdns=go+1.
+
+The Go resolver will send an EDNS0 additional header with a DNS request,
+to signal a willingness to accept a larger DNS packet size.
+This can reportedly cause sporadic failures with the DNS server run
+by some modems and routers. Setting GODEBUG=netedns0=0 will disable
+sending the additional header.
+
+On macOS, if Go code that uses the net package is built with
+-buildmode=c-archive, linking the resulting archive into a C program
+requires passing -lresolv when linking the C code.
+
+On Plan 9, the resolver always accesses /net/cs and /net/dns.
+
+On Windows, in Go 1.18.x and earlier, the resolver always used C
+library functions, such as GetAddrInfo and DnsQuery.
+*/
+package net
+
+import (
+ "context"
+ "errors"
+ "internal/poll"
+ "io"
+ "os"
+ "sync"
+ "syscall"
+ "time"
+ _ "unsafe" // for linkname
+)
+
+// Addr represents a network end point address.
+//
+// The two methods [Addr.Network] and [Addr.String] conventionally return strings
+// that can be passed as the arguments to [Dial], but the exact form
+// and meaning of the strings is up to the implementation.
+type Addr interface {
+ Network() string // name of the network (for example, "tcp", "udp")
+ String() string // string form of address (for example, "192.0.2.1:25", "[2001:db8::1]:80")
+}
+
+// Conn is a generic stream-oriented network connection.
+//
+// Multiple goroutines may invoke methods on a Conn simultaneously.
+type Conn interface {
+ // Read reads data from the connection.
+ // Read can be made to time out and return an error after a fixed
+ // time limit; see SetDeadline and SetReadDeadline.
+ Read(b []byte) (n int, err error)
+
+ // Write writes data to the connection.
+ // Write can be made to time out and return an error after a fixed
+ // time limit; see SetDeadline and SetWriteDeadline.
+ Write(b []byte) (n int, err error)
+
+ // Close closes the connection.
+ // Any blocked Read or Write operations will be unblocked and return errors.
+ // Close may or may not block until any buffered data is sent;
+ // for TCP connections see [*TCPConn.SetLinger].
+ Close() error
+
+ // LocalAddr returns the local network address, if known.
+ LocalAddr() Addr
+
+ // RemoteAddr returns the remote network address, if known.
+ RemoteAddr() Addr
+
+ // SetDeadline sets the read and write deadlines associated
+ // with the connection. It is equivalent to calling both
+ // SetReadDeadline and SetWriteDeadline.
+ //
+ // A deadline is an absolute time after which I/O operations
+ // fail instead of blocking. The deadline applies to all future
+ // and pending I/O, not just the immediately following call to
+ // Read or Write. After a deadline has been exceeded, the
+ // connection can be refreshed by setting a deadline in the future.
+ //
+ // If the deadline is exceeded a call to Read or Write or to other
+ // I/O methods will return an error that wraps os.ErrDeadlineExceeded.
+ // This can be tested using errors.Is(err, os.ErrDeadlineExceeded).
+ // The error's Timeout method will return true, but note that there
+ // are other possible errors for which the Timeout method will
+ // return true even if the deadline has not been exceeded.
+ //
+ // An idle timeout can be implemented by repeatedly extending
+ // the deadline after successful Read or Write calls.
+ //
+ // A zero value for t means I/O operations will not time out.
+ SetDeadline(t time.Time) error
+
+ // SetReadDeadline sets the deadline for future Read calls
+ // and any currently-blocked Read call.
+ // A zero value for t means Read will not time out.
+ SetReadDeadline(t time.Time) error
+
+ // SetWriteDeadline sets the deadline for future Write calls
+ // and any currently-blocked Write call.
+ // Even if write times out, it may return n > 0, indicating that
+ // some of the data was successfully written.
+ // A zero value for t means Write will not time out.
+ SetWriteDeadline(t time.Time) error
+}
+
+type conn struct {
+ fd *netFD
+}
+
+func (c *conn) ok() bool { return c != nil && c.fd != nil }
+
+// Implementation of the Conn interface.
+
+// Read implements the Conn Read method.
+func (c *conn) Read(b []byte) (int, error) {
+ if !c.ok() {
+ return 0, syscall.EINVAL
+ }
+ n, err := c.fd.Read(b)
+ if err != nil && err != io.EOF {
+ err = &OpError{Op: "read", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+ }
+ return n, err
+}
+
+// Write implements the Conn Write method.
+func (c *conn) Write(b []byte) (int, error) {
+ if !c.ok() {
+ return 0, syscall.EINVAL
+ }
+ n, err := c.fd.Write(b)
+ if err != nil {
+ err = &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+ }
+ return n, err
+}
+
+// Close closes the connection.
+func (c *conn) Close() error {
+ if !c.ok() {
+ return syscall.EINVAL
+ }
+ err := c.fd.Close()
+ if err != nil {
+ err = &OpError{Op: "close", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+ }
+ return err
+}
+
+// LocalAddr returns the local network address.
+// The Addr returned is shared by all invocations of LocalAddr, so
+// do not modify it.
+func (c *conn) LocalAddr() Addr {
+ if !c.ok() {
+ return nil
+ }
+ return c.fd.laddr
+}
+
+// RemoteAddr returns the remote network address.
+// The Addr returned is shared by all invocations of RemoteAddr, so
+// do not modify it.
+func (c *conn) RemoteAddr() Addr {
+ if !c.ok() {
+ return nil
+ }
+ return c.fd.raddr
+}
+
+// SetDeadline implements the Conn SetDeadline method.
+func (c *conn) SetDeadline(t time.Time) error {
+ if !c.ok() {
+ return syscall.EINVAL
+ }
+ if err := c.fd.SetDeadline(t); err != nil {
+ return &OpError{Op: "set", Net: c.fd.net, Source: nil, Addr: c.fd.laddr, Err: err}
+ }
+ return nil
+}
+
+// SetReadDeadline implements the Conn SetReadDeadline method.
+func (c *conn) SetReadDeadline(t time.Time) error {
+ if !c.ok() {
+ return syscall.EINVAL
+ }
+ if err := c.fd.SetReadDeadline(t); err != nil {
+ return &OpError{Op: "set", Net: c.fd.net, Source: nil, Addr: c.fd.laddr, Err: err}
+ }
+ return nil
+}
+
+// SetWriteDeadline implements the Conn SetWriteDeadline method.
+func (c *conn) SetWriteDeadline(t time.Time) error {
+ if !c.ok() {
+ return syscall.EINVAL
+ }
+ if err := c.fd.SetWriteDeadline(t); err != nil {
+ return &OpError{Op: "set", Net: c.fd.net, Source: nil, Addr: c.fd.laddr, Err: err}
+ }
+ return nil
+}
+
+// SetReadBuffer sets the size of the operating system's
+// receive buffer associated with the connection.
+func (c *conn) SetReadBuffer(bytes int) error {
+ if !c.ok() {
+ return syscall.EINVAL
+ }
+ if err := setReadBuffer(c.fd, bytes); err != nil {
+ return &OpError{Op: "set", Net: c.fd.net, Source: nil, Addr: c.fd.laddr, Err: err}
+ }
+ return nil
+}
+
+// SetWriteBuffer sets the size of the operating system's
+// transmit buffer associated with the connection.
+func (c *conn) SetWriteBuffer(bytes int) error {
+ if !c.ok() {
+ return syscall.EINVAL
+ }
+ if err := setWriteBuffer(c.fd, bytes); err != nil {
+ return &OpError{Op: "set", Net: c.fd.net, Source: nil, Addr: c.fd.laddr, Err: err}
+ }
+ return nil
+}
+
+// File returns a copy of the underlying [os.File].
+// It is the caller's responsibility to close f when finished.
+// Closing c does not affect f, and closing f does not affect c.
+//
+// The returned os.File's file descriptor is different from the connection's.
+// Attempting to change properties of the original using this duplicate
+// may or may not have the desired effect.
+//
+// On Windows, the returned os.File's file descriptor is not usable
+// on other processes.
+func (c *conn) File() (f *os.File, err error) {
+ f, err = c.fd.dup()
+ if err != nil {
+ err = &OpError{Op: "file", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+ }
+ return
+}
+
+// PacketConn is a generic packet-oriented network connection.
+//
+// Multiple goroutines may invoke methods on a PacketConn simultaneously.
+type PacketConn interface {
+ // ReadFrom reads a packet from the connection,
+ // copying the payload into p. It returns the number of
+ // bytes copied into p and the return address that
+ // was on the packet.
+ // It returns the number of bytes read (0 <= n <= len(p))
+ // and any error encountered. Callers should always process
+ // the n > 0 bytes returned before considering the error err.
+ // ReadFrom can be made to time out and return an error after a
+ // fixed time limit; see SetDeadline and SetReadDeadline.
+ ReadFrom(p []byte) (n int, addr Addr, err error)
+
+ // WriteTo writes a packet with payload p to addr.
+ // WriteTo can be made to time out and return an Error after a
+ // fixed time limit; see SetDeadline and SetWriteDeadline.
+ // On packet-oriented connections, write timeouts are rare.
+ WriteTo(p []byte, addr Addr) (n int, err error)
+
+ // Close closes the connection.
+ // Any blocked ReadFrom or WriteTo operations will be unblocked and return errors.
+ Close() error
+
+ // LocalAddr returns the local network address, if known.
+ LocalAddr() Addr
+
+ // SetDeadline sets the read and write deadlines associated
+ // with the connection. It is equivalent to calling both
+ // SetReadDeadline and SetWriteDeadline.
+ //
+ // A deadline is an absolute time after which I/O operations
+ // fail instead of blocking. The deadline applies to all future
+ // and pending I/O, not just the immediately following call to
+ // Read or Write. After a deadline has been exceeded, the
+ // connection can be refreshed by setting a deadline in the future.
+ //
+ // If the deadline is exceeded a call to Read or Write or to other
+ // I/O methods will return an error that wraps os.ErrDeadlineExceeded.
+ // This can be tested using errors.Is(err, os.ErrDeadlineExceeded).
+ // The error's Timeout method will return true, but note that there
+ // are other possible errors for which the Timeout method will
+ // return true even if the deadline has not been exceeded.
+ //
+ // An idle timeout can be implemented by repeatedly extending
+ // the deadline after successful ReadFrom or WriteTo calls.
+ //
+ // A zero value for t means I/O operations will not time out.
+ SetDeadline(t time.Time) error
+
+ // SetReadDeadline sets the deadline for future ReadFrom calls
+ // and any currently-blocked ReadFrom call.
+ // A zero value for t means ReadFrom will not time out.
+ SetReadDeadline(t time.Time) error
+
+ // SetWriteDeadline sets the deadline for future WriteTo calls
+ // and any currently-blocked WriteTo call.
+ // Even if write times out, it may return n > 0, indicating that
+ // some of the data was successfully written.
+ // A zero value for t means WriteTo will not time out.
+ SetWriteDeadline(t time.Time) error
+}
+
+var listenerBacklogCache struct {
+ sync.Once
+ val int
+}
+
+// listenerBacklog is a caching wrapper around maxListenerBacklog.
+//
+// listenerBacklog should be an internal detail,
+// but widely used packages access it using linkname.
+// Notable members of the hall of shame include:
+// - github.com/database64128/tfo-go/v2
+// - github.com/metacubex/tfo-go
+// - github.com/sagernet/tfo-go
+//
+// Do not remove or change the type signature.
+// See go.dev/issue/67401.
+//
+//go:linkname listenerBacklog
+func listenerBacklog() int {
+ listenerBacklogCache.Do(func() { listenerBacklogCache.val = maxListenerBacklog() })
+ return listenerBacklogCache.val
+}
+
+// A Listener is a generic network listener for stream-oriented protocols.
+//
+// Multiple goroutines may invoke methods on a Listener simultaneously.
+type Listener interface {
+ // Accept waits for and returns the next connection to the listener.
+ Accept() (Conn, error)
+
+ // Close closes the listener.
+ // Any blocked Accept operations will be unblocked and return errors.
+ Close() error
+
+ // Addr returns the listener's network address.
+ Addr() Addr
+}
+
+// An Error represents a network error.
+type Error interface {
+ error
+ Timeout() bool // Is the error a timeout?
+
+ // Deprecated: Temporary errors are not well-defined.
+ // Most "temporary" errors are timeouts, and the few exceptions are surprising.
+ // Do not use this method.
+ Temporary() bool
+}
+
+// Various errors contained in OpError.
+var (
+ // For connection setup operations.
+ errNoSuitableAddress = errors.New("no suitable address found")
+
+ // For connection setup and write operations.
+ errMissingAddress = errors.New("missing address")
+
+ // For both read and write operations.
+ errCanceled = canceledError{}
+ ErrWriteToConnected = errors.New("use of WriteTo with pre-connected connection")
+)
+
+// canceledError lets us return the same error string we have always
+// returned, while still being Is context.Canceled.
+type canceledError struct{}
+
+func (canceledError) Error() string { return "operation was canceled" }
+
+func (canceledError) Is(err error) bool { return err == context.Canceled }
+
+// mapErr maps from the context errors to the historical internal net
+// error values.
+func mapErr(err error) error {
+ switch err {
+ case context.Canceled:
+ return errCanceled
+ case context.DeadlineExceeded:
+ return errTimeout
+ default:
+ return err
+ }
+}
+
+// OpError is the error type usually returned by functions in the net
+// package. It describes the operation, network type, and address of
+// an error.
+type OpError struct {
+ // Op is the operation which caused the error, such as
+ // "read" or "write".
+ Op string
+
+ // Net is the network type on which this error occurred,
+ // such as "tcp" or "udp6".
+ Net string
+
+ // For operations involving a remote network connection, like
+ // Dial, Read, or Write, Source is the corresponding local
+ // network address.
+ Source Addr
+
+ // Addr is the network address for which this error occurred.
+ // For local operations, like Listen or SetDeadline, Addr is
+ // the address of the local endpoint being manipulated.
+ // For operations involving a remote network connection, like
+ // Dial, Read, or Write, Addr is the remote address of that
+ // connection.
+ Addr Addr
+
+ // Err is the error that occurred during the operation.
+ // The Error method panics if the error is nil.
+ Err error
+}
+
+func (e *OpError) Unwrap() error { return e.Err }
+
+func (e *OpError) Error() string {
+ if e == nil {
+ return ""
+ }
+ s := e.Op
+ if e.Net != "" {
+ s += " " + e.Net
+ }
+ if e.Source != nil {
+ s += " " + e.Source.String()
+ }
+ if e.Addr != nil {
+ if e.Source != nil {
+ s += "->"
+ } else {
+ s += " "
+ }
+ s += e.Addr.String()
+ }
+ s += ": " + e.Err.Error()
+ return s
+}
+
+var (
+ // aLongTimeAgo is a non-zero time, far in the past, used for
+ // immediate cancellation of dials.
+ aLongTimeAgo = time.Unix(1, 0)
+
+ // noDeadline and noCancel are just zero values for
+ // readability with functions taking too many parameters.
+ noDeadline = time.Time{}
+ noCancel = (chan struct{})(nil)
+)
+
+type timeout interface {
+ Timeout() bool
+}
+
+func (e *OpError) Timeout() bool {
+ if ne, ok := e.Err.(*os.SyscallError); ok {
+ t, ok := ne.Err.(timeout)
+ return ok && t.Timeout()
+ }
+ t, ok := e.Err.(timeout)
+ return ok && t.Timeout()
+}
+
+type temporary interface {
+ Temporary() bool
+}
+
+func (e *OpError) Temporary() bool {
+ // Treat ECONNRESET and ECONNABORTED as temporary errors when
+ // they come from calling accept. See issue 6163.
+ if e.Op == "accept" && isConnError(e.Err) {
+ return true
+ }
+
+ if ne, ok := e.Err.(*os.SyscallError); ok {
+ t, ok := ne.Err.(temporary)
+ return ok && t.Temporary()
+ }
+ t, ok := e.Err.(temporary)
+ return ok && t.Temporary()
+}
+
+// A ParseError is the error type of literal network address parsers.
+type ParseError struct {
+ // Type is the type of string that was expected, such as
+ // "IP address", "CIDR address".
+ Type string
+
+ // Text is the malformed text string.
+ Text string
+}
+
+func (e *ParseError) Error() string { return "invalid " + e.Type + ": " + e.Text }
+
+func (e *ParseError) Timeout() bool { return false }
+func (e *ParseError) Temporary() bool { return false }
+
+type AddrError struct {
+ Err string
+ Addr string
+}
+
+func (e *AddrError) Error() string {
+ if e == nil {
+ return ""
+ }
+ s := e.Err
+ if e.Addr != "" {
+ s = "address " + e.Addr + ": " + s
+ }
+ return s
+}
+
+func (e *AddrError) Timeout() bool { return false }
+func (e *AddrError) Temporary() bool { return false }
+
+type UnknownNetworkError string
+
+func (e UnknownNetworkError) Error() string { return "unknown network " + string(e) }
+func (e UnknownNetworkError) Timeout() bool { return false }
+func (e UnknownNetworkError) Temporary() bool { return false }
+
+type InvalidAddrError string
+
+func (e InvalidAddrError) Error() string { return string(e) }
+func (e InvalidAddrError) Timeout() bool { return false }
+func (e InvalidAddrError) Temporary() bool { return false }
+
+// errTimeout exists to return the historical "i/o timeout" string
+// for context.DeadlineExceeded. See mapErr.
+// It is also used when Dialer.Deadline is exceeded.
+// error.Is(errTimeout, context.DeadlineExceeded) returns true.
+//
+// TODO(iant): We could consider changing this to os.ErrDeadlineExceeded
+// in the future, if we make
+//
+// errors.Is(os.ErrDeadlineExceeded, context.DeadlineExceeded)
+//
+// return true.
+var errTimeout error = &timeoutError{}
+
+type timeoutError struct{}
+
+func (e *timeoutError) Error() string { return "i/o timeout" }
+func (e *timeoutError) Timeout() bool { return true }
+func (e *timeoutError) Temporary() bool { return true }
+
+func (e *timeoutError) Is(err error) bool {
+ return err == context.DeadlineExceeded
+}
+
+// DNSConfigError represents an error reading the machine's DNS configuration.
+// (No longer used; kept for compatibility.)
+type DNSConfigError struct {
+ Err error
+}
+
+func (e *DNSConfigError) Unwrap() error { return e.Err }
+func (e *DNSConfigError) Error() string { return "error reading DNS config: " + e.Err.Error() }
+func (e *DNSConfigError) Timeout() bool { return false }
+func (e *DNSConfigError) Temporary() bool { return false }
+
+// Various errors contained in DNSError.
+var (
+ errNoSuchHost = ¬FoundError{"no such host"}
+ errUnknownPort = ¬FoundError{"unknown port"}
+)
+
+// notFoundError is a special error understood by the newDNSError function,
+// which causes a creation of a DNSError with IsNotFound field set to true.
+type notFoundError struct{ s string }
+
+func (e *notFoundError) Error() string { return e.s }
+
+// temporaryError is an error type that implements the [Error] interface.
+// It returns true from the Temporary method.
+type temporaryError struct{ s string }
+
+func (e *temporaryError) Error() string { return e.s }
+func (e *temporaryError) Temporary() bool { return true }
+func (e *temporaryError) Timeout() bool { return false }
+
+// DNSError represents a DNS lookup error.
+type DNSError struct {
+ UnwrapErr error // error returned by the [DNSError.Unwrap] method, might be nil
+ Err string // description of the error
+ Name string // name looked for
+ Server string // server used
+ IsTimeout bool // if true, timed out; not all timeouts set this
+ IsTemporary bool // if true, error is temporary; not all errors set this
+
+ // IsNotFound is set to true when the requested name does not
+ // contain any records of the requested type (data not found),
+ // or the name itself was not found (NXDOMAIN).
+ IsNotFound bool
+}
+
+// newDNSError creates a new *DNSError.
+// Based on the err, it sets the UnwrapErr, IsTimeout, IsTemporary, IsNotFound fields.
+func newDNSError(err error, name, server string) *DNSError {
+ var (
+ isTimeout bool
+ isTemporary bool
+ unwrapErr error
+ )
+
+ if err, ok := err.(Error); ok {
+ isTimeout = err.Timeout()
+ isTemporary = err.Temporary()
+ }
+
+ // At this time, the only errors we wrap are context errors, to allow
+ // users to check for canceled/timed out requests.
+ if errors.Is(err, context.DeadlineExceeded) || errors.Is(err, context.Canceled) {
+ unwrapErr = err
+ }
+
+ _, isNotFound := err.(*notFoundError)
+ return &DNSError{
+ UnwrapErr: unwrapErr,
+ Err: err.Error(),
+ Name: name,
+ Server: server,
+ IsTimeout: isTimeout,
+ IsTemporary: isTemporary,
+ IsNotFound: isNotFound,
+ }
+}
+
+// Unwrap returns e.UnwrapErr.
+func (e *DNSError) Unwrap() error { return e.UnwrapErr }
+
+func (e *DNSError) Error() string {
+ if e == nil {
+ return ""
+ }
+ s := "lookup " + e.Name
+ if e.Server != "" {
+ s += " on " + e.Server
+ }
+ s += ": " + e.Err
+ return s
+}
+
+// Timeout reports whether the DNS lookup is known to have timed out.
+// This is not always known; a DNS lookup may fail due to a timeout
+// and return a [DNSError] for which Timeout returns false.
+func (e *DNSError) Timeout() bool { return e.IsTimeout }
+
+// Temporary reports whether the DNS error is known to be temporary.
+// This is not always known; a DNS lookup may fail due to a temporary
+// error and return a [DNSError] for which Temporary returns false.
+func (e *DNSError) Temporary() bool { return e.IsTimeout || e.IsTemporary }
+
+// errClosed exists just so that the docs for ErrClosed don't mention
+// the internal package poll.
+var errClosed = poll.ErrNetClosing
+
+// ErrClosed is the error returned by an I/O call on a network
+// connection that has already been closed, or that is closed by
+// another goroutine before the I/O is completed. This may be wrapped
+// in another error, and should normally be tested using
+// errors.Is(err, net.ErrClosed).
+var ErrClosed error = errClosed
+
+// noReadFrom can be embedded alongside another type to
+// hide the ReadFrom method of that other type.
+type noReadFrom struct{}
+
+// ReadFrom hides another ReadFrom method.
+// It should never be called.
+func (noReadFrom) ReadFrom(io.Reader) (int64, error) {
+ panic("can't happen")
+}
+
+// tcpConnWithoutReadFrom implements all the methods of *TCPConn other
+// than ReadFrom. This is used to permit ReadFrom to call io.Copy
+// without leading to a recursive call to ReadFrom.
+type tcpConnWithoutReadFrom struct {
+ noReadFrom
+ *TCPConn
+}
+
+// Fallback implementation of io.ReaderFrom's ReadFrom, when sendfile isn't
+// applicable.
+func genericReadFrom(c *TCPConn, r io.Reader) (n int64, err error) {
+ // Use wrapper to hide existing r.ReadFrom from io.Copy.
+ return io.Copy(tcpConnWithoutReadFrom{TCPConn: c}, r)
+}
+
+// noWriteTo can be embedded alongside another type to
+// hide the WriteTo method of that other type.
+type noWriteTo struct{}
+
+// WriteTo hides another WriteTo method.
+// It should never be called.
+func (noWriteTo) WriteTo(io.Writer) (int64, error) {
+ panic("can't happen")
+}
+
+// tcpConnWithoutWriteTo implements all the methods of *TCPConn other
+// than WriteTo. This is used to permit WriteTo to call io.Copy
+// without leading to a recursive call to WriteTo.
+type tcpConnWithoutWriteTo struct {
+ noWriteTo
+ *TCPConn
+}
+
+// Fallback implementation of io.WriterTo's WriteTo, when zero-copy isn't applicable.
+func genericWriteTo(c *TCPConn, w io.Writer) (n int64, err error) {
+ // Use wrapper to hide existing w.WriteTo from io.Copy.
+ return io.Copy(w, tcpConnWithoutWriteTo{TCPConn: c})
+}
+
+// Limit the number of concurrent cgo-using goroutines, because
+// each will block an entire operating system thread. The usual culprit
+// is resolving many DNS names in separate goroutines but the DNS
+// server is not responding. Then the many lookups each use a different
+// thread, and the system or the program runs out of threads.
+
+var threadLimit chan struct{}
+
+var threadOnce sync.Once
+
+func acquireThread(ctx context.Context) error {
+ threadOnce.Do(func() {
+ threadLimit = make(chan struct{}, concurrentThreadsLimit())
+ })
+ select {
+ case threadLimit <- struct{}{}:
+ return nil
+ case <-ctx.Done():
+ return ctx.Err()
+ }
+}
+
+func releaseThread() {
+ <-threadLimit
+}
+
+// buffersWriter is the interface implemented by Conns that support a
+// "writev"-like batch write optimization.
+// writeBuffers should fully consume and write all chunks from the
+// provided Buffers, else it should report a non-nil error.
+type buffersWriter interface {
+ writeBuffers(*Buffers) (int64, error)
+}
+
+// Buffers contains zero or more runs of bytes to write.
+//
+// On certain machines, for certain types of connections, this is
+// optimized into an OS-specific batch write operation (such as
+// "writev").
+type Buffers [][]byte
+
+var (
+ _ io.WriterTo = (*Buffers)(nil)
+ _ io.Reader = (*Buffers)(nil)
+)
+
+// WriteTo writes contents of the buffers to w.
+//
+// WriteTo implements [io.WriterTo] for [Buffers].
+//
+// WriteTo modifies the slice v as well as v[i] for 0 <= i < len(v),
+// but does not modify v[i][j] for any i, j.
+func (v *Buffers) WriteTo(w io.Writer) (n int64, err error) {
+ if wv, ok := w.(buffersWriter); ok {
+ return wv.writeBuffers(v)
+ }
+ for _, b := range *v {
+ nb, err := w.Write(b)
+ n += int64(nb)
+ if err != nil {
+ v.consume(n)
+ return n, err
+ }
+ }
+ v.consume(n)
+ return n, nil
+}
+
+// Read from the buffers.
+//
+// Read implements [io.Reader] for [Buffers].
+//
+// Read modifies the slice v as well as v[i] for 0 <= i < len(v),
+// but does not modify v[i][j] for any i, j.
+func (v *Buffers) Read(p []byte) (n int, err error) {
+ for len(p) > 0 && len(*v) > 0 {
+ n0 := copy(p, (*v)[0])
+ v.consume(int64(n0))
+ p = p[n0:]
+ n += n0
+ }
+ if len(*v) == 0 {
+ err = io.EOF
+ }
+ return
+}
+
+func (v *Buffers) consume(n int64) {
+ for len(*v) > 0 {
+ ln0 := int64(len((*v)[0]))
+ if ln0 > n {
+ (*v)[0] = (*v)[0][n:]
+ return
+ }
+ n -= ln0
+ (*v)[0] = nil
+ *v = (*v)[1:]
+ }
+}
diff --git a/go/src/net/net_fake.go b/go/src/net/net_fake.go
new file mode 100644
index 0000000000000000000000000000000000000000..cc35d90a26742fc3cd248f1cf2e96260ecbf7f45
--- /dev/null
+++ b/go/src/net/net_fake.go
@@ -0,0 +1,1165 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Fake networking for js/wasm and wasip1/wasm.
+// It is intended to allow tests of other package to pass.
+
+//go:build js || wasip1
+
+package net
+
+import (
+ "context"
+ "errors"
+ "io"
+ "os"
+ "sync"
+ "sync/atomic"
+ "syscall"
+ "time"
+)
+
+var (
+ sockets sync.Map // fakeSockAddr → *netFD
+ fakePorts sync.Map // int (port #) → *netFD
+ nextPortCounter atomic.Int32
+)
+
+const defaultBuffer = 65535
+
+type fakeSockAddr struct {
+ family int
+ address string
+}
+
+func fakeAddr(sa sockaddr) fakeSockAddr {
+ return fakeSockAddr{
+ family: sa.family(),
+ address: sa.String(),
+ }
+}
+
+// socket returns a network file descriptor that is ready for
+// I/O using the fake network.
+func socket(ctx context.Context, net string, family, sotype, proto int, ipv6only bool, laddr, raddr sockaddr, ctrlCtxFn func(context.Context, string, string, syscall.RawConn) error) (*netFD, error) {
+ if raddr != nil && ctrlCtxFn != nil {
+ return nil, os.NewSyscallError("socket", syscall.ENOTSUP)
+ }
+ switch sotype {
+ case syscall.SOCK_STREAM, syscall.SOCK_SEQPACKET, syscall.SOCK_DGRAM:
+ default:
+ return nil, os.NewSyscallError("socket", syscall.ENOTSUP)
+ }
+
+ fd := &netFD{
+ family: family,
+ sotype: sotype,
+ net: net,
+ }
+ fd.fakeNetFD = newFakeNetFD(fd)
+
+ if raddr == nil {
+ if err := fakeListen(fd, laddr); err != nil {
+ fd.Close()
+ return nil, err
+ }
+ return fd, nil
+ }
+
+ if err := fakeConnect(ctx, fd, laddr, raddr); err != nil {
+ fd.Close()
+ return nil, err
+ }
+ return fd, nil
+}
+
+func validateResolvedAddr(net string, family int, sa sockaddr) error {
+ validateIP := func(ip IP) error {
+ switch family {
+ case syscall.AF_INET:
+ if len(ip) != 4 {
+ return &AddrError{
+ Err: "non-IPv4 address",
+ Addr: ip.String(),
+ }
+ }
+ case syscall.AF_INET6:
+ if len(ip) != 16 {
+ return &AddrError{
+ Err: "non-IPv6 address",
+ Addr: ip.String(),
+ }
+ }
+ default:
+ panic("net: unexpected address family in validateResolvedAddr")
+ }
+ return nil
+ }
+
+ switch net {
+ case "tcp", "tcp4", "tcp6":
+ sa, ok := sa.(*TCPAddr)
+ if !ok {
+ return &AddrError{
+ Err: "non-TCP address for " + net + " network",
+ Addr: sa.String(),
+ }
+ }
+ if err := validateIP(sa.IP); err != nil {
+ return err
+ }
+ if sa.Port <= 0 || sa.Port >= 1<<16 {
+ return &AddrError{
+ Err: "port out of range",
+ Addr: sa.String(),
+ }
+ }
+ return nil
+
+ case "udp", "udp4", "udp6":
+ sa, ok := sa.(*UDPAddr)
+ if !ok {
+ return &AddrError{
+ Err: "non-UDP address for " + net + " network",
+ Addr: sa.String(),
+ }
+ }
+ if err := validateIP(sa.IP); err != nil {
+ return err
+ }
+ if sa.Port <= 0 || sa.Port >= 1<<16 {
+ return &AddrError{
+ Err: "port out of range",
+ Addr: sa.String(),
+ }
+ }
+ return nil
+
+ case "unix", "unixgram", "unixpacket":
+ sa, ok := sa.(*UnixAddr)
+ if !ok {
+ return &AddrError{
+ Err: "non-Unix address for " + net + " network",
+ Addr: sa.String(),
+ }
+ }
+ if sa.Name != "" {
+ i := len(sa.Name) - 1
+ for i > 0 && !os.IsPathSeparator(sa.Name[i]) {
+ i--
+ }
+ for i > 0 && os.IsPathSeparator(sa.Name[i]) {
+ i--
+ }
+ if i <= 0 {
+ return &AddrError{
+ Err: "unix socket name missing path component",
+ Addr: sa.Name,
+ }
+ }
+ if _, err := os.Stat(sa.Name[:i+1]); err != nil {
+ return &AddrError{
+ Err: err.Error(),
+ Addr: sa.Name,
+ }
+ }
+ }
+ return nil
+
+ default:
+ return &AddrError{
+ Err: syscall.EAFNOSUPPORT.Error(),
+ Addr: sa.String(),
+ }
+ }
+}
+
+func matchIPFamily(family int, addr sockaddr) sockaddr {
+ convertIP := func(ip IP) IP {
+ switch family {
+ case syscall.AF_INET:
+ return ip.To4()
+ case syscall.AF_INET6:
+ return ip.To16()
+ default:
+ return ip
+ }
+ }
+
+ switch addr := addr.(type) {
+ case *TCPAddr:
+ ip := convertIP(addr.IP)
+ if ip == nil || len(ip) == len(addr.IP) {
+ return addr
+ }
+ return &TCPAddr{IP: ip, Port: addr.Port, Zone: addr.Zone}
+ case *UDPAddr:
+ ip := convertIP(addr.IP)
+ if ip == nil || len(ip) == len(addr.IP) {
+ return addr
+ }
+ return &UDPAddr{IP: ip, Port: addr.Port, Zone: addr.Zone}
+ default:
+ return addr
+ }
+}
+
+type fakeNetFD struct {
+ fd *netFD
+ assignedPort int // 0 if no port has been assigned for this socket
+
+ queue *packetQueue // incoming packets
+ peer *netFD // connected peer (for outgoing packets); nil for listeners and PacketConns
+ readDeadline atomic.Pointer[deadlineTimer]
+ writeDeadline atomic.Pointer[deadlineTimer]
+
+ fakeAddr fakeSockAddr // cached fakeSockAddr equivalent of fd.laddr
+
+ // The incoming channels hold incoming connections that have not yet been accepted.
+ // All of these channels are 1-buffered.
+ incoming chan []*netFD // holds the queue when it has >0 but = q.readBufferBytes:
+ pq.full <- q
+ case q.head == nil:
+ if q.nBytes > 0 {
+ defer panic("net: put with nil packet list and nonzero nBytes")
+ }
+ pq.empty <- q
+ default:
+ pq.ready <- q
+ }
+}
+
+func (pq *packetQueue) closeRead() error {
+ q := pq.get()
+ q.readClosed = true
+ pq.put(q)
+ return nil
+}
+
+func (pq *packetQueue) closeWrite() error {
+ q := pq.get()
+ q.writeClosed = true
+ pq.put(q)
+ return nil
+}
+
+func (pq *packetQueue) setLinger(linger bool) error {
+ q := pq.get()
+ defer func() { pq.put(q) }()
+
+ if q.writeClosed {
+ return ErrClosed
+ }
+ q.noLinger = !linger
+ return nil
+}
+
+func (pq *packetQueue) write(dt *deadlineTimer, b []byte, from sockaddr) (n int, err error) {
+ for {
+ dn := len(b)
+ if dn > maxPacketSize {
+ dn = maxPacketSize
+ }
+
+ dn, err = pq.send(dt, b[:dn], from, true)
+ n += dn
+ if err != nil {
+ return n, err
+ }
+
+ b = b[dn:]
+ if len(b) == 0 {
+ return n, nil
+ }
+ }
+}
+
+func (pq *packetQueue) send(dt *deadlineTimer, b []byte, from sockaddr, block bool) (n int, err error) {
+ if from == nil {
+ return 0, os.NewSyscallError("send", syscall.EINVAL)
+ }
+ if len(b) > maxPacketSize {
+ return 0, os.NewSyscallError("send", syscall.EMSGSIZE)
+ }
+
+ var q packetQueueState
+ var full chan packetQueueState
+ if !block {
+ full = pq.full
+ }
+
+ select {
+ case <-dt.expired:
+ return 0, os.ErrDeadlineExceeded
+
+ case q = <-full:
+ pq.put(q)
+ return 0, os.NewSyscallError("send", syscall.ENOBUFS)
+
+ case q = <-pq.empty:
+ case q = <-pq.ready:
+ }
+ defer func() { pq.put(q) }()
+
+ // Don't allow a packet to be sent if the deadline has expired,
+ // even if the select above chose a different branch.
+ select {
+ case <-dt.expired:
+ return 0, os.ErrDeadlineExceeded
+ default:
+ }
+ if q.writeClosed {
+ return 0, ErrClosed
+ } else if q.readClosed && q.nBytes >= q.readBufferBytes {
+ return 0, os.NewSyscallError("send", syscall.ECONNRESET)
+ }
+
+ p := packetPool.Get().(*packet)
+ p.buf = append(p.buf[:0], b...)
+ p.from = from
+
+ if q.head == nil {
+ q.head = p
+ } else {
+ q.tail.next = p
+ }
+ q.tail = p
+ q.nBytes += len(p.buf)
+
+ return len(b), nil
+}
+
+func (pq *packetQueue) recvfrom(dt *deadlineTimer, b []byte, wholePacket bool, checkFrom func(sockaddr) error) (n int, from sockaddr, err error) {
+ var q packetQueueState
+ var empty chan packetQueueState
+ if len(b) == 0 {
+ // For consistency with the implementation on Unix platforms,
+ // allow a zero-length Read to proceed if the queue is empty.
+ // (Without this, TestZeroByteRead deadlocks.)
+ empty = pq.empty
+ }
+
+ select {
+ case <-dt.expired:
+ return 0, nil, os.ErrDeadlineExceeded
+ case q = <-empty:
+ case q = <-pq.ready:
+ case q = <-pq.full:
+ }
+ defer func() { pq.put(q) }()
+
+ if q.readClosed {
+ return 0, nil, ErrClosed
+ }
+
+ p := q.head
+ if p == nil {
+ switch {
+ case q.writeClosed:
+ if q.noLinger {
+ return 0, nil, os.NewSyscallError("recvfrom", syscall.ECONNRESET)
+ }
+ return 0, nil, io.EOF
+ case len(b) == 0:
+ return 0, nil, nil
+ default:
+ // This should be impossible: pq.full should only contain a non-empty list,
+ // pq.ready should either contain a non-empty list or indicate that the
+ // connection is closed, and we should only receive from pq.empty if
+ // len(b) == 0.
+ panic("net: nil packet list from non-closed packetQueue")
+ }
+ }
+
+ select {
+ case <-dt.expired:
+ return 0, nil, os.ErrDeadlineExceeded
+ default:
+ }
+
+ if checkFrom != nil {
+ if err := checkFrom(p.from); err != nil {
+ return 0, nil, err
+ }
+ }
+
+ n = copy(b, p.buf[p.bufOffset:])
+ from = p.from
+ if wholePacket || p.bufOffset+n == len(p.buf) {
+ q.head = p.next
+ q.nBytes -= len(p.buf)
+ p.clear()
+ packetPool.Put(p)
+ } else {
+ p.bufOffset += n
+ }
+
+ return n, from, nil
+}
+
+// setReadBuffer sets a soft limit on the number of bytes available to read
+// from the pipe.
+func (pq *packetQueue) setReadBuffer(bytes int) error {
+ if bytes <= 0 {
+ return os.NewSyscallError("setReadBuffer", syscall.EINVAL)
+ }
+ q := pq.get() // Use the queue as a lock.
+ q.readBufferBytes = bytes
+ pq.put(q)
+ return nil
+}
+
+type deadlineTimer struct {
+ timer chan *time.Timer
+ expired chan struct{}
+}
+
+func newDeadlineTimer(deadline time.Time) *deadlineTimer {
+ dt := &deadlineTimer{
+ timer: make(chan *time.Timer, 1),
+ expired: make(chan struct{}),
+ }
+ dt.timer <- nil
+ dt.Reset(deadline)
+ return dt
+}
+
+// Reset attempts to reset the timer.
+// If the timer has already expired, Reset returns false.
+func (dt *deadlineTimer) Reset(deadline time.Time) bool {
+ timer := <-dt.timer
+ defer func() { dt.timer <- timer }()
+
+ if deadline.Equal(noDeadline) {
+ if timer != nil && timer.Stop() {
+ timer = nil
+ }
+ return timer == nil
+ }
+
+ d := time.Until(deadline)
+ if d < 0 {
+ // Ensure that a deadline in the past takes effect immediately.
+ defer func() { <-dt.expired }()
+ }
+
+ if timer == nil {
+ timer = time.AfterFunc(d, func() { close(dt.expired) })
+ return true
+ }
+ if !timer.Stop() {
+ return false
+ }
+ timer.Reset(d)
+ return true
+}
+
+func sysSocket(family, sotype, proto int) (int, error) {
+ return 0, os.NewSyscallError("sysSocket", syscall.ENOSYS)
+}
+
+func fakeListen(fd *netFD, laddr sockaddr) (err error) {
+ wrapErr := func(err error) error {
+ if errno, ok := err.(syscall.Errno); ok {
+ err = os.NewSyscallError("listen", errno)
+ }
+ if errors.Is(err, syscall.EADDRINUSE) {
+ return err
+ }
+ if laddr != nil {
+ if _, ok := err.(*AddrError); !ok {
+ err = &AddrError{
+ Err: err.Error(),
+ Addr: laddr.String(),
+ }
+ }
+ }
+ return err
+ }
+
+ ffd := newFakeNetFD(fd)
+ defer func() {
+ if fd.fakeNetFD != ffd {
+ // Failed to register listener; clean up.
+ ffd.Close()
+ }
+ }()
+
+ if err := ffd.assignFakeAddr(matchIPFamily(fd.family, laddr)); err != nil {
+ return wrapErr(err)
+ }
+
+ ffd.fakeAddr = fakeAddr(fd.laddr.(sockaddr))
+ switch fd.sotype {
+ case syscall.SOCK_STREAM, syscall.SOCK_SEQPACKET:
+ ffd.incoming = make(chan []*netFD, 1)
+ ffd.incomingFull = make(chan []*netFD, 1)
+ ffd.incomingEmpty = make(chan bool, 1)
+ ffd.incomingEmpty <- true
+ case syscall.SOCK_DGRAM:
+ ffd.queue = newPacketQueue(defaultBuffer)
+ default:
+ return wrapErr(syscall.EINVAL)
+ }
+
+ fd.fakeNetFD = ffd
+ if _, dup := sockets.LoadOrStore(ffd.fakeAddr, fd); dup {
+ fd.fakeNetFD = nil
+ return wrapErr(syscall.EADDRINUSE)
+ }
+
+ return nil
+}
+
+func fakeConnect(ctx context.Context, fd *netFD, laddr, raddr sockaddr) error {
+ wrapErr := func(err error) error {
+ if errno, ok := err.(syscall.Errno); ok {
+ err = os.NewSyscallError("connect", errno)
+ }
+ if errors.Is(err, syscall.EADDRINUSE) {
+ return err
+ }
+ if terr, ok := err.(interface{ Timeout() bool }); !ok || !terr.Timeout() {
+ // For consistency with the net implementation on other platforms,
+ // if we don't need to preserve the Timeout-ness of err we should
+ // wrap it in an AddrError. (Unfortunately we can't wrap errors
+ // that convey structured information, because AddrError reduces
+ // the wrapped Err to a flat string.)
+ if _, ok := err.(*AddrError); !ok {
+ err = &AddrError{
+ Err: err.Error(),
+ Addr: raddr.String(),
+ }
+ }
+ }
+ return err
+ }
+
+ if fd.isConnected {
+ return wrapErr(syscall.EISCONN)
+ }
+ if ctx.Err() != nil {
+ return wrapErr(syscall.ETIMEDOUT)
+ }
+
+ fd.raddr = matchIPFamily(fd.family, raddr)
+ if err := validateResolvedAddr(fd.net, fd.family, fd.raddr.(sockaddr)); err != nil {
+ return wrapErr(err)
+ }
+
+ if err := fd.fakeNetFD.assignFakeAddr(laddr); err != nil {
+ return wrapErr(err)
+ }
+ fd.fakeNetFD.queue = newPacketQueue(defaultBuffer)
+
+ switch fd.sotype {
+ case syscall.SOCK_DGRAM:
+ if ua, ok := fd.laddr.(*UnixAddr); !ok || ua.Name != "" {
+ fd.fakeNetFD.fakeAddr = fakeAddr(fd.laddr.(sockaddr))
+ if _, dup := sockets.LoadOrStore(fd.fakeNetFD.fakeAddr, fd); dup {
+ return wrapErr(syscall.EADDRINUSE)
+ }
+ }
+ fd.isConnected = true
+ return nil
+
+ case syscall.SOCK_STREAM, syscall.SOCK_SEQPACKET:
+ default:
+ return wrapErr(syscall.EINVAL)
+ }
+
+ fa := fakeAddr(raddr)
+ lni, ok := sockets.Load(fa)
+ if !ok {
+ return wrapErr(syscall.ECONNREFUSED)
+ }
+ ln := lni.(*netFD)
+ if ln.sotype != fd.sotype {
+ return wrapErr(syscall.EPROTOTYPE)
+ }
+ if ln.incoming == nil {
+ return wrapErr(syscall.ECONNREFUSED)
+ }
+
+ peer := &netFD{
+ family: ln.family,
+ sotype: ln.sotype,
+ net: ln.net,
+ laddr: ln.laddr,
+ raddr: fd.laddr,
+ isConnected: true,
+ }
+ peer.fakeNetFD = newFakeNetFD(fd)
+ peer.fakeNetFD.queue = newPacketQueue(defaultBuffer)
+ defer func() {
+ if fd.peer != peer {
+ // Failed to connect; clean up.
+ peer.Close()
+ }
+ }()
+
+ var incoming []*netFD
+ select {
+ case <-ctx.Done():
+ return wrapErr(syscall.ETIMEDOUT)
+ case ok = <-ln.incomingEmpty:
+ case incoming, ok = <-ln.incoming:
+ }
+ if !ok {
+ return wrapErr(syscall.ECONNREFUSED)
+ }
+
+ fd.isConnected = true
+ fd.peer = peer
+ peer.peer = fd
+
+ incoming = append(incoming, peer)
+ if len(incoming) >= listenerBacklog() {
+ ln.incomingFull <- incoming
+ } else {
+ ln.incoming <- incoming
+ }
+ return nil
+}
+
+func (ffd *fakeNetFD) assignFakeAddr(addr sockaddr) error {
+ validate := func(sa sockaddr) error {
+ if err := validateResolvedAddr(ffd.fd.net, ffd.fd.family, sa); err != nil {
+ return err
+ }
+ ffd.fd.laddr = sa
+ return nil
+ }
+
+ assignIP := func(addr sockaddr) error {
+ var (
+ ip IP
+ port int
+ zone string
+ )
+ switch addr := addr.(type) {
+ case *TCPAddr:
+ if addr != nil {
+ ip = addr.IP
+ port = addr.Port
+ zone = addr.Zone
+ }
+ case *UDPAddr:
+ if addr != nil {
+ ip = addr.IP
+ port = addr.Port
+ zone = addr.Zone
+ }
+ default:
+ return validate(addr)
+ }
+
+ if ip == nil {
+ ip = IPv4(127, 0, 0, 1)
+ }
+ switch ffd.fd.family {
+ case syscall.AF_INET:
+ if ip4 := ip.To4(); ip4 != nil {
+ ip = ip4
+ }
+ case syscall.AF_INET6:
+ if ip16 := ip.To16(); ip16 != nil {
+ ip = ip16
+ }
+ }
+ if ip == nil {
+ return syscall.EINVAL
+ }
+
+ if port == 0 {
+ var prevPort int32
+ portWrapped := false
+ nextPort := func() (int, bool) {
+ for {
+ port := nextPortCounter.Add(1)
+ if port <= 0 || port >= 1<<16 {
+ // nextPortCounter ran off the end of the port space.
+ // Bump it back into range.
+ for {
+ if nextPortCounter.CompareAndSwap(port, 0) {
+ break
+ }
+ if port = nextPortCounter.Load(); port >= 0 && port < 1<<16 {
+ break
+ }
+ }
+ if portWrapped {
+ // This is the second wraparound, so we've scanned the whole port space
+ // at least once already and it's time to give up.
+ return 0, false
+ }
+ portWrapped = true
+ prevPort = 0
+ continue
+ }
+
+ if port <= prevPort {
+ // nextPortCounter has wrapped around since the last time we read it.
+ if portWrapped {
+ // This is the second wraparound, so we've scanned the whole port space
+ // at least once already and it's time to give up.
+ return 0, false
+ } else {
+ portWrapped = true
+ }
+ }
+
+ prevPort = port
+ return int(port), true
+ }
+ }
+
+ for {
+ var ok bool
+ port, ok = nextPort()
+ if !ok {
+ ffd.assignedPort = 0
+ return syscall.EADDRINUSE
+ }
+
+ ffd.assignedPort = int(port)
+ if _, dup := fakePorts.LoadOrStore(ffd.assignedPort, ffd.fd); !dup {
+ break
+ }
+ }
+ }
+
+ switch addr.(type) {
+ case *TCPAddr:
+ return validate(&TCPAddr{IP: ip, Port: port, Zone: zone})
+ case *UDPAddr:
+ return validate(&UDPAddr{IP: ip, Port: port, Zone: zone})
+ default:
+ panic("unreachable")
+ }
+ }
+
+ switch ffd.fd.net {
+ case "tcp", "tcp4", "tcp6":
+ if addr == nil {
+ return assignIP(new(TCPAddr))
+ }
+ return assignIP(addr)
+
+ case "udp", "udp4", "udp6":
+ if addr == nil {
+ return assignIP(new(UDPAddr))
+ }
+ return assignIP(addr)
+
+ case "unix", "unixgram", "unixpacket":
+ uaddr, ok := addr.(*UnixAddr)
+ if !ok && addr != nil {
+ return &AddrError{
+ Err: "non-Unix address for " + ffd.fd.net + " network",
+ Addr: addr.String(),
+ }
+ }
+ if uaddr == nil {
+ return validate(&UnixAddr{Net: ffd.fd.net})
+ }
+ return validate(&UnixAddr{Net: ffd.fd.net, Name: uaddr.Name})
+
+ default:
+ return &AddrError{
+ Err: syscall.EAFNOSUPPORT.Error(),
+ Addr: addr.String(),
+ }
+ }
+}
+
+func (ffd *fakeNetFD) readFrom(p []byte) (n int, sa syscall.Sockaddr, err error) {
+ if ffd.queue == nil {
+ return 0, nil, os.NewSyscallError("readFrom", syscall.EINVAL)
+ }
+
+ n, from, err := ffd.queue.recvfrom(ffd.readDeadline.Load(), p, true, nil)
+
+ if from != nil {
+ // Convert the net.sockaddr to a syscall.Sockaddr type.
+ var saErr error
+ sa, saErr = from.sockaddr(ffd.fd.family)
+ if err == nil {
+ err = saErr
+ }
+ }
+
+ return n, sa, err
+}
+
+func (ffd *fakeNetFD) readFromInet4(p []byte, sa *syscall.SockaddrInet4) (n int, err error) {
+ n, _, err = ffd.queue.recvfrom(ffd.readDeadline.Load(), p, true, func(from sockaddr) error {
+ fromSA, err := from.sockaddr(syscall.AF_INET)
+ if err != nil {
+ return err
+ }
+ if fromSA == nil {
+ return os.NewSyscallError("readFromInet4", syscall.EINVAL)
+ }
+ *sa = *(fromSA.(*syscall.SockaddrInet4))
+ return nil
+ })
+ return n, err
+}
+
+func (ffd *fakeNetFD) readFromInet6(p []byte, sa *syscall.SockaddrInet6) (n int, err error) {
+ n, _, err = ffd.queue.recvfrom(ffd.readDeadline.Load(), p, true, func(from sockaddr) error {
+ fromSA, err := from.sockaddr(syscall.AF_INET6)
+ if err != nil {
+ return err
+ }
+ if fromSA == nil {
+ return os.NewSyscallError("readFromInet6", syscall.EINVAL)
+ }
+ *sa = *(fromSA.(*syscall.SockaddrInet6))
+ return nil
+ })
+ return n, err
+}
+
+func (ffd *fakeNetFD) readMsg(p []byte, oob []byte, flags int) (n, oobn, retflags int, sa syscall.Sockaddr, err error) {
+ if flags != 0 {
+ return 0, 0, 0, nil, os.NewSyscallError("readMsg", syscall.ENOTSUP)
+ }
+ n, sa, err = ffd.readFrom(p)
+ return n, 0, 0, sa, err
+}
+
+func (ffd *fakeNetFD) readMsgInet4(p []byte, oob []byte, flags int, sa *syscall.SockaddrInet4) (n, oobn, retflags int, err error) {
+ if flags != 0 {
+ return 0, 0, 0, os.NewSyscallError("readMsgInet4", syscall.ENOTSUP)
+ }
+ n, err = ffd.readFromInet4(p, sa)
+ return n, 0, 0, err
+}
+
+func (ffd *fakeNetFD) readMsgInet6(p []byte, oob []byte, flags int, sa *syscall.SockaddrInet6) (n, oobn, retflags int, err error) {
+ if flags != 0 {
+ return 0, 0, 0, os.NewSyscallError("readMsgInet6", syscall.ENOTSUP)
+ }
+ n, err = ffd.readFromInet6(p, sa)
+ return n, 0, 0, err
+}
+
+func (ffd *fakeNetFD) writeMsg(p []byte, oob []byte, sa syscall.Sockaddr) (n int, oobn int, err error) {
+ if len(oob) > 0 {
+ return 0, 0, os.NewSyscallError("writeMsg", syscall.ENOTSUP)
+ }
+ n, err = ffd.writeTo(p, sa)
+ return n, 0, err
+}
+
+func (ffd *fakeNetFD) writeMsgInet4(p []byte, oob []byte, sa4 *syscall.SockaddrInet4) (n int, oobn int, err error) {
+ var sa syscall.Sockaddr
+ if sa4 != nil {
+ sa = sa4
+ }
+ return ffd.writeMsg(p, oob, sa)
+}
+
+func (ffd *fakeNetFD) writeMsgInet6(p []byte, oob []byte, sa6 *syscall.SockaddrInet6) (n int, oobn int, err error) {
+ var sa syscall.Sockaddr
+ if sa6 != nil {
+ sa = sa6
+ }
+ return ffd.writeMsg(p, oob, sa)
+}
+
+func (ffd *fakeNetFD) writeTo(p []byte, sa syscall.Sockaddr) (n int, err error) {
+ raddr := ffd.fd.raddr
+ if sa != nil {
+ if ffd.fd.isConnected {
+ return 0, os.NewSyscallError("writeTo", syscall.EISCONN)
+ }
+ raddr = ffd.fd.addrFunc()(sa)
+ }
+ if raddr == nil {
+ return 0, os.NewSyscallError("writeTo", syscall.EINVAL)
+ }
+
+ peeri, _ := sockets.Load(fakeAddr(raddr.(sockaddr)))
+ if peeri == nil {
+ if len(ffd.fd.net) >= 3 && ffd.fd.net[:3] == "udp" {
+ return len(p), nil
+ }
+ return 0, os.NewSyscallError("writeTo", syscall.ECONNRESET)
+ }
+ peer := peeri.(*netFD)
+ if peer.queue == nil {
+ if len(ffd.fd.net) >= 3 && ffd.fd.net[:3] == "udp" {
+ return len(p), nil
+ }
+ return 0, os.NewSyscallError("writeTo", syscall.ECONNRESET)
+ }
+
+ block := true
+ if len(ffd.fd.net) >= 3 && ffd.fd.net[:3] == "udp" {
+ block = false
+ }
+ return peer.queue.send(ffd.writeDeadline.Load(), p, ffd.fd.laddr.(sockaddr), block)
+}
+
+func (ffd *fakeNetFD) writeToInet4(p []byte, sa *syscall.SockaddrInet4) (n int, err error) {
+ return ffd.writeTo(p, sa)
+}
+
+func (ffd *fakeNetFD) writeToInet6(p []byte, sa *syscall.SockaddrInet6) (n int, err error) {
+ return ffd.writeTo(p, sa)
+}
+
+func (ffd *fakeNetFD) dup() (f *os.File, err error) {
+ return nil, os.NewSyscallError("dup", syscall.ENOSYS)
+}
+
+func (ffd *fakeNetFD) setReadBuffer(bytes int) error {
+ if ffd.queue == nil {
+ return os.NewSyscallError("setReadBuffer", syscall.EINVAL)
+ }
+ ffd.queue.setReadBuffer(bytes)
+ return nil
+}
+
+func (ffd *fakeNetFD) setWriteBuffer(bytes int) error {
+ return os.NewSyscallError("setWriteBuffer", syscall.ENOTSUP)
+}
+
+func (ffd *fakeNetFD) setLinger(sec int) error {
+ if sec < 0 || ffd.peer == nil {
+ return os.NewSyscallError("setLinger", syscall.EINVAL)
+ }
+ ffd.peer.queue.setLinger(sec > 0)
+ return nil
+}
diff --git a/go/src/net/net_fake_test.go b/go/src/net/net_fake_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..4542228fbc5827f458dac13b033e29111467ddf3
--- /dev/null
+++ b/go/src/net/net_fake_test.go
@@ -0,0 +1,107 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build js || wasip1
+
+package net
+
+// GOOS=js and GOOS=wasip1 do not have typical socket networking capabilities
+// found on other platforms. To help run test suites of the stdlib packages,
+// an in-memory "fake network" facility is implemented.
+//
+// The tests in this files are intended to validate the behavior of the fake
+// network stack on these platforms.
+
+import (
+ "errors"
+ "syscall"
+ "testing"
+)
+
+func TestFakePortExhaustion(t *testing.T) {
+ if testing.Short() {
+ t.Skipf("skipping test that opens 1<<16 connections")
+ }
+
+ ln := newLocalListener(t, "tcp")
+ done := make(chan struct{})
+ go func() {
+ var accepted []Conn
+ defer func() {
+ for _, c := range accepted {
+ c.Close()
+ }
+ close(done)
+ }()
+
+ for {
+ c, err := ln.Accept()
+ if err != nil {
+ return
+ }
+ accepted = append(accepted, c)
+ }
+ }()
+
+ var dialed []Conn
+ defer func() {
+ ln.Close()
+ for _, c := range dialed {
+ c.Close()
+ }
+ <-done
+ }()
+
+ // Since this test is not running in parallel, we expect to be able to open
+ // all 65535 valid (fake) ports. The listener is already using one, so
+ // we should be able to Dial the remaining 65534.
+ for len(dialed) < (1<<16)-2 {
+ c, err := Dial(ln.Addr().Network(), ln.Addr().String())
+ if err != nil {
+ t.Fatalf("unexpected error from Dial with %v connections: %v", len(dialed), err)
+ }
+ dialed = append(dialed, c)
+ if testing.Verbose() && len(dialed)%(1<<12) == 0 {
+ t.Logf("dialed %d connections", len(dialed))
+ }
+ }
+ t.Logf("dialed %d connections", len(dialed))
+
+ // Now that all of the ports are in use, dialing another should fail due
+ // to port exhaustion, which (for POSIX-like socket APIs) should return
+ // an EADDRINUSE error.
+ c, err := Dial(ln.Addr().Network(), ln.Addr().String())
+ if err == nil {
+ c.Close()
+ }
+ if errors.Is(err, syscall.EADDRINUSE) {
+ t.Logf("Dial returned expected error: %v", err)
+ } else {
+ t.Errorf("unexpected error from Dial: %v\nwant: %v", err, syscall.EADDRINUSE)
+ }
+
+ // Opening a Listener should fail at this point too.
+ ln2, err := Listen("tcp", "localhost:0")
+ if err == nil {
+ ln2.Close()
+ }
+ if errors.Is(err, syscall.EADDRINUSE) {
+ t.Logf("Listen returned expected error: %v", err)
+ } else {
+ t.Errorf("unexpected error from Listen: %v\nwant: %v", err, syscall.EADDRINUSE)
+ }
+
+ // When we close an arbitrary connection, we should be able to reuse its port
+ // even if the server hasn't yet seen the ECONNRESET for the connection.
+ dialed[0].Close()
+ dialed = dialed[1:]
+ t.Logf("closed one connection")
+ c, err = Dial(ln.Addr().Network(), ln.Addr().String())
+ if err == nil {
+ c.Close()
+ t.Logf("Dial succeeded")
+ } else {
+ t.Errorf("unexpected error from Dial: %v", err)
+ }
+}
diff --git a/go/src/net/net_test.go b/go/src/net/net_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..637c95540f41bc805c664ab122120a54c44bb07a
--- /dev/null
+++ b/go/src/net/net_test.go
@@ -0,0 +1,612 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "errors"
+ "fmt"
+ "io"
+ "net/internal/socktest"
+ "os"
+ "runtime"
+ "sync"
+ "testing"
+ "time"
+)
+
+func TestCloseRead(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+ t.Parallel()
+
+ for _, network := range []string{"tcp", "unix", "unixpacket"} {
+ t.Run(network, func(t *testing.T) {
+ if !testableNetwork(network) {
+ t.Skipf("network %s is not testable on the current platform", network)
+ }
+ t.Parallel()
+
+ ln := newLocalListener(t, network)
+ switch network {
+ case "unix", "unixpacket":
+ defer os.Remove(ln.Addr().String())
+ }
+ defer ln.Close()
+
+ c, err := Dial(ln.Addr().Network(), ln.Addr().String())
+ if err != nil {
+ t.Fatal(err)
+ }
+ switch network {
+ case "unix", "unixpacket":
+ defer os.Remove(c.LocalAddr().String())
+ }
+ defer c.Close()
+
+ switch c := c.(type) {
+ case *TCPConn:
+ err = c.CloseRead()
+ case *UnixConn:
+ err = c.CloseRead()
+ }
+ if err != nil {
+ if perr := parseCloseError(err, true); perr != nil {
+ t.Error(perr)
+ }
+ t.Fatal(err)
+ }
+ var b [1]byte
+ n, err := c.Read(b[:])
+ if n != 0 || err == nil {
+ t.Fatalf("got (%d, %v); want (0, error)", n, err)
+ }
+ })
+ }
+}
+
+func TestCloseWrite(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+
+ t.Parallel()
+ deadline, _ := t.Deadline()
+ if !deadline.IsZero() {
+ // Leave 10% headroom on the deadline to report errors and clean up.
+ deadline = deadline.Add(-time.Until(deadline) / 10)
+ }
+
+ for _, network := range []string{"tcp", "unix", "unixpacket"} {
+ t.Run(network, func(t *testing.T) {
+ if !testableNetwork(network) {
+ t.Skipf("network %s is not testable on the current platform", network)
+ }
+ t.Parallel()
+
+ handler := func(ls *localServer, ln Listener) {
+ c, err := ln.Accept()
+ if err != nil {
+ t.Error(err)
+ return
+ }
+
+ // Workaround for https://go.dev/issue/49352.
+ // On Windows and arm64 macOS (current as of macOS 12.4),
+ // reading from a socket at the same time as the client
+ // is closing it occasionally hangs for 60 seconds before
+ // returning ECONNRESET. Sleep for a bit to give the
+ // socket time to close before trying to read from it.
+ if runtime.GOOS == "windows" || (runtime.GOOS == "darwin" && runtime.GOARCH == "arm64") {
+ time.Sleep(10 * time.Millisecond)
+ }
+
+ if !deadline.IsZero() {
+ c.SetDeadline(deadline)
+ }
+ defer c.Close()
+
+ var b [1]byte
+ n, err := c.Read(b[:])
+ if n != 0 || err != io.EOF {
+ t.Errorf("got (%d, %v); want (0, io.EOF)", n, err)
+ return
+ }
+ switch c := c.(type) {
+ case *TCPConn:
+ err = c.CloseWrite()
+ case *UnixConn:
+ err = c.CloseWrite()
+ }
+ if err != nil {
+ if perr := parseCloseError(err, true); perr != nil {
+ t.Error(perr)
+ }
+ t.Error(err)
+ return
+ }
+ n, err = c.Write(b[:])
+ if err == nil {
+ t.Errorf("got (%d, %v); want (any, error)", n, err)
+ return
+ }
+ }
+
+ ls := newLocalServer(t, network)
+ defer ls.teardown()
+ if err := ls.buildup(handler); err != nil {
+ t.Fatal(err)
+ }
+
+ c, err := Dial(ls.Listener.Addr().Network(), ls.Listener.Addr().String())
+ if err != nil {
+ t.Fatal(err)
+ }
+ if !deadline.IsZero() {
+ c.SetDeadline(deadline)
+ }
+ switch network {
+ case "unix", "unixpacket":
+ defer os.Remove(c.LocalAddr().String())
+ }
+ defer c.Close()
+
+ switch c := c.(type) {
+ case *TCPConn:
+ err = c.CloseWrite()
+ case *UnixConn:
+ err = c.CloseWrite()
+ }
+ if err != nil {
+ if perr := parseCloseError(err, true); perr != nil {
+ t.Error(perr)
+ }
+ t.Fatal(err)
+ }
+ var b [1]byte
+ n, err := c.Read(b[:])
+ if n != 0 || err != io.EOF {
+ t.Fatalf("got (%d, %v); want (0, io.EOF)", n, err)
+ }
+ n, err = c.Write(b[:])
+ if err == nil {
+ t.Fatalf("got (%d, %v); want (any, error)", n, err)
+ }
+ })
+ }
+}
+
+func TestConnClose(t *testing.T) {
+ t.Parallel()
+ for _, network := range []string{"tcp", "unix", "unixpacket"} {
+ t.Run(network, func(t *testing.T) {
+ if !testableNetwork(network) {
+ t.Skipf("network %s is not testable on the current platform", network)
+ }
+ t.Parallel()
+
+ ln := newLocalListener(t, network)
+ switch network {
+ case "unix", "unixpacket":
+ defer os.Remove(ln.Addr().String())
+ }
+ defer ln.Close()
+
+ c, err := Dial(ln.Addr().Network(), ln.Addr().String())
+ if err != nil {
+ t.Fatal(err)
+ }
+ switch network {
+ case "unix", "unixpacket":
+ defer os.Remove(c.LocalAddr().String())
+ }
+ defer c.Close()
+
+ if err := c.Close(); err != nil {
+ if perr := parseCloseError(err, false); perr != nil {
+ t.Error(perr)
+ }
+ t.Fatal(err)
+ }
+ var b [1]byte
+ n, err := c.Read(b[:])
+ if n != 0 || err == nil {
+ t.Fatalf("got (%d, %v); want (0, error)", n, err)
+ }
+ })
+ }
+}
+
+func TestListenerClose(t *testing.T) {
+ t.Parallel()
+ for _, network := range []string{"tcp", "unix", "unixpacket"} {
+ t.Run(network, func(t *testing.T) {
+ if !testableNetwork(network) {
+ t.Skipf("network %s is not testable on the current platform", network)
+ }
+ t.Parallel()
+
+ ln := newLocalListener(t, network)
+ switch network {
+ case "unix", "unixpacket":
+ defer os.Remove(ln.Addr().String())
+ }
+
+ if err := ln.Close(); err != nil {
+ if perr := parseCloseError(err, false); perr != nil {
+ t.Error(perr)
+ }
+ t.Fatal(err)
+ }
+ c, err := ln.Accept()
+ if err == nil {
+ c.Close()
+ t.Fatal("should fail")
+ }
+
+ // Note: we cannot ensure that a subsequent Dial does not succeed, because
+ // we do not in general have any guarantee that ln.Addr is not immediately
+ // reused. (TCP sockets enter a TIME_WAIT state when closed, but that only
+ // applies to existing connections for the port — it does not prevent the
+ // port itself from being used for entirely new connections in the
+ // meantime.)
+ })
+ }
+}
+
+func TestPacketConnClose(t *testing.T) {
+ t.Parallel()
+ for _, network := range []string{"udp", "unixgram"} {
+ t.Run(network, func(t *testing.T) {
+ if !testableNetwork(network) {
+ t.Skipf("network %s is not testable on the current platform", network)
+ }
+ t.Parallel()
+
+ c := newLocalPacketListener(t, network)
+ switch network {
+ case "unixgram":
+ defer os.Remove(c.LocalAddr().String())
+ }
+ defer c.Close()
+
+ if err := c.Close(); err != nil {
+ if perr := parseCloseError(err, false); perr != nil {
+ t.Error(perr)
+ }
+ t.Fatal(err)
+ }
+ var b [1]byte
+ n, _, err := c.ReadFrom(b[:])
+ if n != 0 || err == nil {
+ t.Fatalf("got (%d, %v); want (0, error)", n, err)
+ }
+ })
+ }
+}
+
+// See golang.org/issue/6163, golang.org/issue/6987.
+func TestAcceptIgnoreAbortedConnRequest(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9":
+ t.Skipf("%s does not have full support of socktest", runtime.GOOS)
+ }
+
+ syserr := make(chan error)
+ go func() {
+ defer close(syserr)
+ for _, err := range abortedConnRequestErrors {
+ syserr <- err
+ }
+ }()
+ sw.Set(socktest.FilterAccept, func(so *socktest.Status) (socktest.AfterFilter, error) {
+ if err, ok := <-syserr; ok {
+ return nil, err
+ }
+ return nil, nil
+ })
+ defer sw.Set(socktest.FilterAccept, nil)
+
+ operr := make(chan error, 1)
+ handler := func(ls *localServer, ln Listener) {
+ defer close(operr)
+ c, err := ln.Accept()
+ if err != nil {
+ if perr := parseAcceptError(err); perr != nil {
+ operr <- perr
+ }
+ operr <- err
+ return
+ }
+ c.Close()
+ }
+ ls := newLocalServer(t, "tcp")
+ defer ls.teardown()
+ if err := ls.buildup(handler); err != nil {
+ t.Fatal(err)
+ }
+
+ c, err := Dial(ls.Listener.Addr().Network(), ls.Listener.Addr().String())
+ if err != nil {
+ t.Fatal(err)
+ }
+ c.Close()
+
+ for err := range operr {
+ t.Error(err)
+ }
+}
+
+func TestZeroByteRead(t *testing.T) {
+ t.Parallel()
+ for _, network := range []string{"tcp", "unix", "unixpacket"} {
+ t.Run(network, func(t *testing.T) {
+ if !testableNetwork(network) {
+ t.Skipf("network %s is not testable on the current platform", network)
+ }
+ t.Parallel()
+
+ ln := newLocalListener(t, network)
+ connc := make(chan Conn, 1)
+ defer func() {
+ ln.Close()
+ for c := range connc {
+ if c != nil {
+ c.Close()
+ }
+ }
+ }()
+ go func() {
+ defer close(connc)
+ c, err := ln.Accept()
+ if err != nil {
+ t.Error(err)
+ }
+ connc <- c // might be nil
+ }()
+ c, err := Dial(network, ln.Addr().String())
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer c.Close()
+ sc := <-connc
+ if sc == nil {
+ return
+ }
+ defer sc.Close()
+
+ if runtime.GOOS == "windows" {
+ // A zero byte read on Windows caused a wait for readability first.
+ // Rather than change that behavior, satisfy it in this test.
+ // See Issue 15735.
+ go io.WriteString(sc, "a")
+ }
+
+ n, err := c.Read(nil)
+ if n != 0 || err != nil {
+ t.Errorf("%s: zero byte client read = %v, %v; want 0, nil", network, n, err)
+ }
+
+ if runtime.GOOS == "windows" {
+ // Same as comment above.
+ go io.WriteString(c, "a")
+ }
+ n, err = sc.Read(nil)
+ if n != 0 || err != nil {
+ t.Errorf("%s: zero byte server read = %v, %v; want 0, nil", network, n, err)
+ }
+ })
+ }
+}
+
+// withTCPConnPair sets up a TCP connection between two peers, then
+// runs peer1 and peer2 concurrently. withTCPConnPair returns when
+// both have completed.
+func withTCPConnPair(t *testing.T, peer1, peer2 func(c *TCPConn) error) {
+ t.Helper()
+ ln := newLocalListener(t, "tcp")
+ defer ln.Close()
+ errc := make(chan error, 2)
+ go func() {
+ c1, err := ln.Accept()
+ if err != nil {
+ errc <- err
+ return
+ }
+ err = peer1(c1.(*TCPConn))
+ c1.Close()
+ errc <- err
+ }()
+ go func() {
+ c2, err := Dial("tcp", ln.Addr().String())
+ if err != nil {
+ errc <- err
+ return
+ }
+ err = peer2(c2.(*TCPConn))
+ c2.Close()
+ errc <- err
+ }()
+ for i := 0; i < 2; i++ {
+ if err := <-errc; err != nil {
+ t.Error(err)
+ }
+ }
+}
+
+// Tests that a blocked Read is interrupted by a concurrent SetReadDeadline
+// modifying that Conn's read deadline to the past.
+// See golang.org/cl/30164 which documented this. The net/http package
+// depends on this.
+func TestReadTimeoutUnblocksRead(t *testing.T) {
+ serverDone := make(chan struct{})
+ server := func(cs *TCPConn) error {
+ defer close(serverDone)
+ errc := make(chan error, 1)
+ go func() {
+ defer close(errc)
+ go func() {
+ // TODO: find a better way to wait
+ // until we're blocked in the cs.Read
+ // call below. Sleep is lame.
+ time.Sleep(100 * time.Millisecond)
+
+ // Interrupt the upcoming Read, unblocking it:
+ cs.SetReadDeadline(time.Unix(123, 0)) // time in the past
+ }()
+ var buf [1]byte
+ n, err := cs.Read(buf[:1])
+ if n != 0 || err == nil {
+ errc <- fmt.Errorf("Read = %v, %v; want 0, non-nil", n, err)
+ }
+ }()
+ select {
+ case err := <-errc:
+ return err
+ case <-time.After(5 * time.Second):
+ buf := make([]byte, 2<<20)
+ buf = buf[:runtime.Stack(buf, true)]
+ println("Stacks at timeout:\n", string(buf))
+ return errors.New("timeout waiting for Read to finish")
+ }
+
+ }
+ // Do nothing in the client. Never write. Just wait for the
+ // server's half to be done.
+ client := func(*TCPConn) error {
+ <-serverDone
+ return nil
+ }
+ withTCPConnPair(t, client, server)
+}
+
+// Issue 17695: verify that a blocked Read is woken up by a Close.
+func TestCloseUnblocksRead(t *testing.T) {
+ t.Parallel()
+ server := func(cs *TCPConn) error {
+ // Give the client time to get stuck in a Read:
+ time.Sleep(20 * time.Millisecond)
+ cs.Close()
+ return nil
+ }
+ client := func(ss *TCPConn) error {
+ n, err := ss.Read([]byte{0})
+ if n != 0 || err != io.EOF {
+ return fmt.Errorf("Read = %v, %v; want 0, EOF", n, err)
+ }
+ return nil
+ }
+ withTCPConnPair(t, client, server)
+}
+
+// Issue 72770: verify that a blocked UDP read is woken up by a Close.
+func TestCloseUnblocksReadUDP(t *testing.T) {
+ t.Parallel()
+ var (
+ mu sync.Mutex
+ done bool
+ )
+ defer func() {
+ mu.Lock()
+ defer mu.Unlock()
+ done = true
+ }()
+ pc, err := ListenPacket("udp", "127.0.0.1:0")
+ if err != nil {
+ t.Fatal(err)
+ }
+ time.AfterFunc(250*time.Millisecond, func() {
+ mu.Lock()
+ defer mu.Unlock()
+ if done {
+ return
+ }
+ t.Logf("closing conn...")
+ pc.Close()
+ })
+ timer := time.AfterFunc(time.Second*10, func() {
+ panic("timeout waiting for Close")
+ })
+ defer timer.Stop()
+
+ n, src, err := pc.(*UDPConn).ReadFromUDPAddrPort([]byte{})
+
+ // Check for n > 0. Checking err == nil alone isn't enough;
+ // on macOS, it returns (n=0, src=0.0.0.0:0, err=nil).
+ if n > 0 {
+ t.Fatalf("unexpected Read success from ReadFromUDPAddrPort; read %d bytes from %v, err=%v", n, src, err)
+ }
+ t.Logf("got expected UDP read error")
+}
+
+// Issue 24808: verify that ECONNRESET is not temporary for read.
+func TestNotTemporaryRead(t *testing.T) {
+ t.Parallel()
+
+ ln := newLocalListener(t, "tcp")
+ serverDone := make(chan struct{})
+ dialed := make(chan struct{})
+ go func() {
+ defer close(serverDone)
+
+ cs, err := ln.Accept()
+ if err != nil {
+ return
+ }
+ <-dialed
+ cs.(*TCPConn).SetLinger(0)
+ cs.Close()
+ }()
+ defer func() {
+ ln.Close()
+ <-serverDone
+ }()
+
+ ss, err := Dial("tcp", ln.Addr().String())
+ close(dialed)
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer ss.Close()
+
+ _, err = ss.Read([]byte{0})
+ if err == nil {
+ t.Fatal("Read succeeded unexpectedly")
+ } else if err == io.EOF {
+ // This happens on Plan 9, but for some reason (prior to CL 385314) it was
+ // accepted everywhere else too.
+ if runtime.GOOS == "plan9" {
+ return
+ }
+ t.Fatal("Read unexpectedly returned io.EOF after socket was abruptly closed")
+ }
+ if ne, ok := err.(Error); !ok {
+ t.Errorf("Read error does not implement net.Error: %v", err)
+ } else if ne.Temporary() {
+ t.Errorf("Read error is unexpectedly temporary: %v", err)
+ }
+}
+
+// The various errors should implement the Error interface.
+func TestErrors(t *testing.T) {
+ var (
+ _ Error = &OpError{}
+ _ Error = &ParseError{}
+ _ Error = &AddrError{}
+ _ Error = UnknownNetworkError("")
+ _ Error = InvalidAddrError("")
+ _ Error = &timeoutError{}
+ _ Error = &DNSConfigError{}
+ _ Error = &DNSError{}
+ )
+
+ // ErrClosed was introduced as type error, so we can't check
+ // it using a declaration.
+ if _, ok := ErrClosed.(Error); !ok {
+ t.Fatal("ErrClosed does not implement Error")
+ }
+}
diff --git a/go/src/net/net_windows_test.go b/go/src/net/net_windows_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..0a5c77f032527ef3d411fa629119840f61d53412
--- /dev/null
+++ b/go/src/net/net_windows_test.go
@@ -0,0 +1,627 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "bufio"
+ "bytes"
+ "fmt"
+ "internal/testenv"
+ "io"
+ "os"
+ "os/exec"
+ "regexp"
+ "slices"
+ "strings"
+ "syscall"
+ "testing"
+ "time"
+)
+
+func toErrno(err error) (syscall.Errno, bool) {
+ operr, ok := err.(*OpError)
+ if !ok {
+ return 0, false
+ }
+ syserr, ok := operr.Err.(*os.SyscallError)
+ if !ok {
+ return 0, false
+ }
+ errno, ok := syserr.Err.(syscall.Errno)
+ if !ok {
+ return 0, false
+ }
+ return errno, true
+}
+
+// TestAcceptIgnoreSomeErrors tests that windows TCPListener.AcceptTCP
+// handles broken connections. It verifies that broken connections do
+// not affect future connections.
+func TestAcceptIgnoreSomeErrors(t *testing.T) {
+ recv := func(ln Listener, ignoreSomeReadErrors bool) (string, error) {
+ c, err := ln.Accept()
+ if err != nil {
+ // Display windows errno in error message.
+ errno, ok := toErrno(err)
+ if !ok {
+ return "", err
+ }
+ return "", fmt.Errorf("%v (windows errno=%d)", err, errno)
+ }
+ defer c.Close()
+
+ b := make([]byte, 100)
+ n, err := c.Read(b)
+ if err == nil || err == io.EOF {
+ return string(b[:n]), nil
+ }
+ errno, ok := toErrno(err)
+ if ok && ignoreSomeReadErrors && (errno == syscall.ERROR_NETNAME_DELETED || errno == syscall.WSAECONNRESET) {
+ return "", nil
+ }
+ return "", err
+ }
+
+ send := func(addr string, data string) error {
+ c, err := Dial("tcp", addr)
+ if err != nil {
+ return err
+ }
+ defer c.Close()
+
+ b := []byte(data)
+ n, err := c.Write(b)
+ if err != nil {
+ return err
+ }
+ if n != len(b) {
+ return fmt.Errorf(`Only %d chars of string "%s" sent`, n, data)
+ }
+ return nil
+ }
+
+ if envaddr := os.Getenv("GOTEST_DIAL_ADDR"); envaddr != "" {
+ // In child process.
+ c, err := Dial("tcp", envaddr)
+ if err != nil {
+ t.Fatal(err)
+ }
+ fmt.Printf("sleeping\n")
+ time.Sleep(time.Minute) // process will be killed here
+ c.Close()
+ }
+
+ ln, err := Listen("tcp", "127.0.0.1:0")
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer ln.Close()
+
+ // Start child process that connects to our listener.
+ cmd := exec.Command(testenv.Executable(t), "-test.run=^TestAcceptIgnoreSomeErrors$")
+ cmd.Env = append(os.Environ(), "GOTEST_DIAL_ADDR="+ln.Addr().String())
+ stdout, err := cmd.StdoutPipe()
+ if err != nil {
+ t.Fatalf("cmd.StdoutPipe failed: %v", err)
+ }
+ err = cmd.Start()
+ if err != nil {
+ t.Fatalf("cmd.Start failed: %v\n", err)
+ }
+ outReader := bufio.NewReader(stdout)
+ for {
+ s, err := outReader.ReadString('\n')
+ if err != nil {
+ t.Fatalf("reading stdout failed: %v", err)
+ }
+ if s == "sleeping\n" {
+ break
+ }
+ }
+ defer cmd.Wait() // ignore error - we know it is getting killed
+
+ const alittle = 100 * time.Millisecond
+ time.Sleep(alittle)
+ cmd.Process.Kill() // the only way to trigger the errors
+ time.Sleep(alittle)
+
+ // Send second connection data (with delay in a separate goroutine).
+ result := make(chan error)
+ go func() {
+ time.Sleep(alittle)
+ err := send(ln.Addr().String(), "abc")
+ if err != nil {
+ result <- err
+ }
+ result <- nil
+ }()
+ defer func() {
+ err := <-result
+ if err != nil {
+ t.Fatalf("send failed: %v", err)
+ }
+ }()
+
+ // Receive first or second connection.
+ s, err := recv(ln, true)
+ if err != nil {
+ t.Fatalf("recv failed: %v", err)
+ }
+ switch s {
+ case "":
+ // First connection data is received, let's get second connection data.
+ case "abc":
+ // First connection is lost forever, but that is ok.
+ return
+ default:
+ t.Fatalf(`"%s" received from recv, but "" or "abc" expected`, s)
+ }
+
+ // Get second connection data.
+ s, err = recv(ln, false)
+ if err != nil {
+ t.Fatalf("recv failed: %v", err)
+ }
+ if s != "abc" {
+ t.Fatalf(`"%s" received from recv, but "abc" expected`, s)
+ }
+}
+
+func runCmd(args ...string) ([]byte, error) {
+ removeUTF8BOM := func(b []byte) []byte {
+ if len(b) >= 3 && b[0] == 0xEF && b[1] == 0xBB && b[2] == 0xBF {
+ return b[3:]
+ }
+ return b
+ }
+ f, err := os.CreateTemp("", "netcmd")
+ if err != nil {
+ return nil, err
+ }
+ f.Close()
+ defer os.Remove(f.Name())
+ cmd := fmt.Sprintf(`%s | Out-File "%s" -encoding UTF8`, strings.Join(args, " "), f.Name())
+ out, err := exec.Command("powershell", "-Command", cmd).CombinedOutput()
+ if err != nil {
+ if len(out) != 0 {
+ return nil, fmt.Errorf("%s failed: %v: %q", args[0], err, string(removeUTF8BOM(out)))
+ }
+ var err2 error
+ out, err2 = os.ReadFile(f.Name())
+ if err2 != nil {
+ return nil, err2
+ }
+ if len(out) != 0 {
+ return nil, fmt.Errorf("%s failed: %v: %q", args[0], err, string(removeUTF8BOM(out)))
+ }
+ return nil, fmt.Errorf("%s failed: %v", args[0], err)
+ }
+ out, err = os.ReadFile(f.Name())
+ if err != nil {
+ return nil, err
+ }
+ return removeUTF8BOM(out), nil
+}
+
+func checkNetsh(t *testing.T) {
+ if testenv.Builder() == "windows-arm64-10" {
+ // netsh was observed to sometimes hang on this builder.
+ // We have not observed failures on windows-arm64-11, so for the
+ // moment we are leaving the test enabled elsewhere on the theory
+ // that it may have been a platform bug fixed in Windows 11.
+ testenv.SkipFlaky(t, 52082)
+ }
+ out, err := runCmd("netsh", "help")
+ if err != nil {
+ t.Fatal(err)
+ }
+ if bytes.Contains(out, []byte("The following helper DLL cannot be loaded")) {
+ t.Skipf("powershell failure:\n%s", err)
+ }
+ if !bytes.Contains(out, []byte("The following commands are available:")) {
+ t.Skipf("powershell does not speak English:\n%s", out)
+ }
+}
+
+func netshInterfaceIPShowInterface(ipver string, ifaces map[string]bool) error {
+ out, err := runCmd("netsh", "interface", ipver, "show", "interface", "level=verbose")
+ if err != nil {
+ return err
+ }
+ // interface information is listed like:
+ //
+ //Interface Local Area Connection Parameters
+ //----------------------------------------------
+ //IfLuid : ethernet_6
+ //IfIndex : 11
+ //State : connected
+ //Metric : 10
+ //...
+ var name string
+ for line := range bytes.SplitSeq(out, []byte{'\r', '\n'}) {
+ if bytes.HasPrefix(line, []byte("Interface ")) && bytes.HasSuffix(line, []byte(" Parameters")) {
+ f := line[len("Interface "):]
+ f = f[:len(f)-len(" Parameters")]
+ name = string(f)
+ continue
+ }
+ var isup bool
+ switch string(line) {
+ case "State : connected":
+ isup = true
+ case "State : disconnected":
+ isup = false
+ default:
+ continue
+ }
+ if name != "" {
+ if v, ok := ifaces[name]; ok && v != isup {
+ return fmt.Errorf("%s:%s isup=%v: ipv4 and ipv6 report different interface state", ipver, name, isup)
+ }
+ ifaces[name] = isup
+ name = ""
+ }
+ }
+ return nil
+}
+
+func TestInterfacesWithNetsh(t *testing.T) {
+ checkNetsh(t)
+
+ toString := func(name string, isup bool) string {
+ if isup {
+ return name + ":up"
+ }
+ return name + ":down"
+ }
+
+ ift, err := Interfaces()
+ if err != nil {
+ t.Fatal(err)
+ }
+ have := make([]string, 0)
+ for _, ifi := range ift {
+ have = append(have, toString(ifi.Name, ifi.Flags&FlagUp != 0))
+ }
+ slices.Sort(have)
+
+ ifaces := make(map[string]bool)
+ err = netshInterfaceIPShowInterface("ipv6", ifaces)
+ if err != nil {
+ t.Fatal(err)
+ }
+ err = netshInterfaceIPShowInterface("ipv4", ifaces)
+ if err != nil {
+ t.Fatal(err)
+ }
+ want := make([]string, 0)
+ for name, isup := range ifaces {
+ want = append(want, toString(name, isup))
+ }
+ slices.Sort(want)
+
+ if !slices.Equal(want, have) {
+ t.Fatalf("unexpected interface list %q, want %q", have, want)
+ }
+}
+
+func netshInterfaceIPv4ShowAddress(name string, netshOutput []byte) []string {
+ // Address information is listed like:
+ //
+ //Configuration for interface "Local Area Connection"
+ // DHCP enabled: Yes
+ // IP Address: 10.0.0.2
+ // Subnet Prefix: 10.0.0.0/24 (mask 255.255.255.0)
+ // IP Address: 10.0.0.3
+ // Subnet Prefix: 10.0.0.0/24 (mask 255.255.255.0)
+ // Default Gateway: 10.0.0.254
+ // Gateway Metric: 0
+ // InterfaceMetric: 10
+ //
+ //Configuration for interface "Loopback Pseudo-Interface 1"
+ // DHCP enabled: No
+ // IP Address: 127.0.0.1
+ // Subnet Prefix: 127.0.0.0/8 (mask 255.0.0.0)
+ // InterfaceMetric: 50
+ //
+ addrs := make([]string, 0)
+ var addr, subnetprefix string
+ var processingOurInterface bool
+ for line := range bytes.SplitSeq(netshOutput, []byte{'\r', '\n'}) {
+ if !processingOurInterface {
+ if !bytes.HasPrefix(line, []byte("Configuration for interface")) {
+ continue
+ }
+ if !bytes.Contains(line, []byte(`"`+name+`"`)) {
+ continue
+ }
+ processingOurInterface = true
+ continue
+ }
+ if len(line) == 0 {
+ break
+ }
+ if bytes.Contains(line, []byte("Subnet Prefix:")) {
+ f := bytes.Split(line, []byte{':'})
+ if len(f) == 2 {
+ f = bytes.Split(f[1], []byte{'('})
+ if len(f) == 2 {
+ f = bytes.Split(f[0], []byte{'/'})
+ if len(f) == 2 {
+ subnetprefix = string(bytes.TrimSpace(f[1]))
+ if addr != "" && subnetprefix != "" {
+ addrs = append(addrs, addr+"/"+subnetprefix)
+ }
+ }
+ }
+ }
+ }
+ addr = ""
+ if bytes.Contains(line, []byte("IP Address:")) {
+ f := bytes.Split(line, []byte{':'})
+ if len(f) == 2 {
+ addr = string(bytes.TrimSpace(f[1]))
+ }
+ }
+ }
+ return addrs
+}
+
+func netshInterfaceIPv6ShowAddress(name string, netshOutput []byte) []string {
+ // Address information is listed like:
+ //
+ //Address ::1 Parameters
+ //---------------------------------------------------------
+ //Interface Luid : Loopback Pseudo-Interface 1
+ //Scope Id : 0.0
+ //Valid Lifetime : infinite
+ //Preferred Lifetime : infinite
+ //DAD State : Preferred
+ //Address Type : Other
+ //Skip as Source : false
+ //
+ //Address XXXX::XXXX:XXXX:XXXX:XXXX%11 Parameters
+ //---------------------------------------------------------
+ //Interface Luid : Local Area Connection
+ //Scope Id : 0.11
+ //Valid Lifetime : infinite
+ //Preferred Lifetime : infinite
+ //DAD State : Preferred
+ //Address Type : Other
+ //Skip as Source : false
+ //
+
+ // TODO: need to test ipv6 netmask too, but netsh does not outputs it
+ var addr string
+ addrs := make([]string, 0)
+ for line := range bytes.SplitSeq(netshOutput, []byte{'\r', '\n'}) {
+ if addr != "" {
+ if len(line) == 0 {
+ addr = ""
+ continue
+ }
+ if string(line) != "Interface Luid : "+name {
+ continue
+ }
+ addrs = append(addrs, addr)
+ addr = ""
+ continue
+ }
+ if !bytes.HasPrefix(line, []byte("Address")) {
+ continue
+ }
+ if !bytes.HasSuffix(line, []byte("Parameters")) {
+ continue
+ }
+ f := bytes.Split(line, []byte{' '})
+ if len(f) != 3 {
+ continue
+ }
+ // remove scope ID if present
+ f = bytes.Split(f[1], []byte{'%'})
+
+ // netsh can create IPv4-embedded IPv6 addresses, like fe80::5efe:192.168.140.1.
+ // Convert these to all hexadecimal fe80::5efe:c0a8:8c01 for later string comparisons.
+ ipv4Tail := regexp.MustCompile(`:\d+\.\d+\.\d+\.\d+$`)
+ if ipv4Tail.Match(f[0]) {
+ f[0] = []byte(ParseIP(string(f[0])).String())
+ }
+
+ addr = string(bytes.ToLower(bytes.TrimSpace(f[0])))
+ }
+ return addrs
+}
+
+func TestInterfaceAddrsWithNetsh(t *testing.T) {
+ checkNetsh(t)
+
+ outIPV4, err := runCmd("netsh", "interface", "ipv4", "show", "address")
+ if err != nil {
+ t.Fatal(err)
+ }
+ outIPV6, err := runCmd("netsh", "interface", "ipv6", "show", "address", "level=verbose")
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ ift, err := Interfaces()
+ if err != nil {
+ t.Fatal(err)
+ }
+ for _, ifi := range ift {
+ // Skip the interface if it's down.
+ if (ifi.Flags & FlagUp) == 0 {
+ continue
+ }
+ have := make([]string, 0)
+ addrs, err := ifi.Addrs()
+ if err != nil {
+ t.Fatal(err)
+ }
+ for _, addr := range addrs {
+ switch addr := addr.(type) {
+ case *IPNet:
+ if addr.IP.To4() != nil {
+ have = append(have, addr.String())
+ }
+ if addr.IP.To16() != nil && addr.IP.To4() == nil {
+ // netsh does not output netmask for ipv6, so ignore ipv6 mask
+ have = append(have, addr.IP.String())
+ }
+ case *IPAddr:
+ if addr.IP.To4() != nil {
+ have = append(have, addr.String())
+ }
+ if addr.IP.To16() != nil && addr.IP.To4() == nil {
+ // netsh does not output netmask for ipv6, so ignore ipv6 mask
+ have = append(have, addr.IP.String())
+ }
+ }
+ }
+ slices.Sort(have)
+
+ want := netshInterfaceIPv4ShowAddress(ifi.Name, outIPV4)
+ wantIPv6 := netshInterfaceIPv6ShowAddress(ifi.Name, outIPV6)
+ want = append(want, wantIPv6...)
+ slices.Sort(want)
+
+ if !slices.Equal(want, have) {
+ t.Errorf("%s: unexpected addresses list %q, want %q", ifi.Name, have, want)
+ }
+ }
+}
+
+// check that getmac exists as a powershell command, and that it
+// speaks English.
+func checkGetmac(t *testing.T) {
+ out, err := runCmd("getmac", "/?")
+ if err != nil {
+ if strings.Contains(err.Error(), "term 'getmac' is not recognized as the name of a cmdlet") {
+ t.Skipf("getmac not available")
+ }
+ t.Fatal(err)
+ }
+ if !bytes.Contains(out, []byte("network adapters on a system")) {
+ t.Skipf("skipping test on non-English system")
+ }
+}
+
+func TestInterfaceHardwareAddrWithGetmac(t *testing.T) {
+ checkGetmac(t)
+
+ ift, err := Interfaces()
+ if err != nil {
+ t.Fatal(err)
+ }
+ have := make(map[string]string)
+ for _, ifi := range ift {
+ if ifi.Flags&FlagLoopback != 0 {
+ // no MAC address for loopback interfaces
+ continue
+ }
+ have[ifi.Name] = ifi.HardwareAddr.String()
+ }
+
+ out, err := runCmd("getmac", "/fo", "list", "/v")
+ if err != nil {
+ t.Fatal(err)
+ }
+ // getmac output looks like:
+ //
+ //Connection Name: Local Area Connection
+ //Network Adapter: Intel Gigabit Network Connection
+ //Physical Address: XX-XX-XX-XX-XX-XX
+ //Transport Name: \Device\Tcpip_{XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX}
+ //
+ //Connection Name: Wireless Network Connection
+ //Network Adapter: Wireles WLAN Card
+ //Physical Address: XX-XX-XX-XX-XX-XX
+ //Transport Name: Media disconnected
+ //
+ //Connection Name: Bluetooth Network Connection
+ //Network Adapter: Bluetooth Device (Personal Area Network)
+ //Physical Address: N/A
+ //Transport Name: Hardware not present
+ //
+ //Connection Name: VMware Network Adapter VMnet8
+ //Network Adapter: VMware Virtual Ethernet Adapter for VMnet8
+ //Physical Address: Disabled
+ //Transport Name: Disconnected
+ //
+ want := make(map[string]string)
+ group := make(map[string]string) // name / values for single adapter
+ getValue := func(name string) string {
+ value, found := group[name]
+ if !found {
+ t.Fatalf("%q has no %q line in it", group, name)
+ }
+ if value == "" {
+ t.Fatalf("%q has empty %q value", group, name)
+ }
+ return value
+ }
+ processGroup := func() {
+ if len(group) == 0 {
+ return
+ }
+ tname := strings.ToLower(getValue("Transport Name"))
+ if tname == "n/a" {
+ // skip these
+ return
+ }
+ addr := strings.ToLower(getValue("Physical Address"))
+ if addr == "disabled" || addr == "n/a" {
+ // skip these
+ return
+ }
+ addr = strings.ReplaceAll(addr, "-", ":")
+ cname := getValue("Connection Name")
+ want[cname] = addr
+ group = make(map[string]string)
+ }
+ for line := range bytes.SplitSeq(out, []byte{'\r', '\n'}) {
+ if len(line) == 0 {
+ processGroup()
+ continue
+ }
+ i := bytes.IndexByte(line, ':')
+ if i == -1 {
+ t.Fatalf("line %q has no : in it", line)
+ }
+ group[string(line[:i])] = string(bytes.TrimSpace(line[i+1:]))
+ }
+ processGroup()
+
+ dups := make(map[string][]string)
+ for name, addr := range want {
+ if _, ok := dups[addr]; !ok {
+ dups[addr] = make([]string, 0)
+ }
+ dups[addr] = append(dups[addr], name)
+ }
+
+nextWant:
+ for name, wantAddr := range want {
+ if haveAddr, ok := have[name]; ok {
+ if haveAddr != wantAddr {
+ t.Errorf("unexpected MAC address for %q - %v, want %v", name, haveAddr, wantAddr)
+ }
+ continue
+ }
+ // We could not find the interface in getmac output by name.
+ // But sometimes getmac lists many interface names
+ // for the same MAC address. If that is the case here,
+ // and we can match at least one of those names,
+ // let's ignore the other names.
+ if dupNames, ok := dups[wantAddr]; ok && len(dupNames) > 1 {
+ for _, dupName := range dupNames {
+ if haveAddr, ok := have[dupName]; ok && haveAddr == wantAddr {
+ continue nextWant
+ }
+ }
+ }
+ t.Errorf("getmac lists %q, but it could not be found among Go interfaces %v", name, have)
+ }
+}
diff --git a/go/src/net/netcgo_off.go b/go/src/net/netcgo_off.go
new file mode 100644
index 0000000000000000000000000000000000000000..54677dcac6cd7987c3eddd570aae8c8f18316e86
--- /dev/null
+++ b/go/src/net/netcgo_off.go
@@ -0,0 +1,9 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !netcgo
+
+package net
+
+const netCgoBuildTag = false
diff --git a/go/src/net/netcgo_on.go b/go/src/net/netcgo_on.go
new file mode 100644
index 0000000000000000000000000000000000000000..25d4bdca72a0449c5d8de847f2ec5b97c47d57f9
--- /dev/null
+++ b/go/src/net/netcgo_on.go
@@ -0,0 +1,9 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build netcgo
+
+package net
+
+const netCgoBuildTag = true
diff --git a/go/src/net/netgo_netcgo.go b/go/src/net/netgo_netcgo.go
new file mode 100644
index 0000000000000000000000000000000000000000..7f3a5fd007fb43b3bdce55379cef74cd48415b2d
--- /dev/null
+++ b/go/src/net/netgo_netcgo.go
@@ -0,0 +1,14 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build netgo && netcgo
+
+package net
+
+func init() {
+ // This will give a compile time error about the unused constant.
+ // The advantage of this approach is that the gc compiler
+ // actually prints the constant, making the problem obvious.
+ "Do not use both netgo and netcgo build tags."
+}
diff --git a/go/src/net/netgo_off.go b/go/src/net/netgo_off.go
new file mode 100644
index 0000000000000000000000000000000000000000..e6bc2d7d069d11c9598b5e50748f34938e92247c
--- /dev/null
+++ b/go/src/net/netgo_off.go
@@ -0,0 +1,9 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !netgo
+
+package net
+
+const netGoBuildTag = false
diff --git a/go/src/net/netgo_on.go b/go/src/net/netgo_on.go
new file mode 100644
index 0000000000000000000000000000000000000000..4f088de6e3f80bf83c289d3dcaba19fe5ec83538
--- /dev/null
+++ b/go/src/net/netgo_on.go
@@ -0,0 +1,9 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build netgo
+
+package net
+
+const netGoBuildTag = true
diff --git a/go/src/net/nss.go b/go/src/net/nss.go
new file mode 100644
index 0000000000000000000000000000000000000000..092b515cc7d01ed6d68cf0cf17e1ab8e167c6ded
--- /dev/null
+++ b/go/src/net/nss.go
@@ -0,0 +1,249 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "errors"
+ "internal/bytealg"
+ "os"
+ "sync"
+ "time"
+)
+
+const (
+ nssConfigPath = "/etc/nsswitch.conf"
+)
+
+var nssConfig nsswitchConfig
+
+type nsswitchConfig struct {
+ initOnce sync.Once // guards init of nsswitchConfig
+
+ // ch is used as a semaphore that only allows one lookup at a
+ // time to recheck nsswitch.conf
+ ch chan struct{} // guards lastChecked and modTime
+ lastChecked time.Time // last time nsswitch.conf was checked
+
+ mu sync.Mutex // protects nssConf
+ nssConf *nssConf
+}
+
+func getSystemNSS() *nssConf {
+ nssConfig.tryUpdate()
+ nssConfig.mu.Lock()
+ conf := nssConfig.nssConf
+ nssConfig.mu.Unlock()
+ return conf
+}
+
+// init initializes conf and is only called via conf.initOnce.
+func (conf *nsswitchConfig) init() {
+ conf.nssConf = parseNSSConfFile("/etc/nsswitch.conf")
+ conf.lastChecked = time.Now()
+ conf.ch = make(chan struct{}, 1)
+}
+
+// tryUpdate tries to update conf.
+func (conf *nsswitchConfig) tryUpdate() {
+ conf.initOnce.Do(conf.init)
+
+ // Ensure only one update at a time checks nsswitch.conf
+ if !conf.tryAcquireSema() {
+ return
+ }
+ defer conf.releaseSema()
+
+ now := time.Now()
+ if conf.lastChecked.After(now.Add(-5 * time.Second)) {
+ return
+ }
+ conf.lastChecked = now
+
+ var mtime time.Time
+ if fi, err := os.Stat(nssConfigPath); err == nil {
+ mtime = fi.ModTime()
+ }
+ if mtime.Equal(conf.nssConf.mtime) {
+ return
+ }
+
+ nssConf := parseNSSConfFile(nssConfigPath)
+ conf.mu.Lock()
+ conf.nssConf = nssConf
+ conf.mu.Unlock()
+}
+
+func (conf *nsswitchConfig) acquireSema() {
+ conf.ch <- struct{}{}
+}
+
+func (conf *nsswitchConfig) tryAcquireSema() bool {
+ select {
+ case conf.ch <- struct{}{}:
+ return true
+ default:
+ return false
+ }
+}
+
+func (conf *nsswitchConfig) releaseSema() {
+ <-conf.ch
+}
+
+// nssConf represents the state of the machine's /etc/nsswitch.conf file.
+type nssConf struct {
+ mtime time.Time // time of nsswitch.conf modification
+ err error // any error encountered opening or parsing the file
+ sources map[string][]nssSource // keyed by database (e.g. "hosts")
+}
+
+type nssSource struct {
+ source string // e.g. "compat", "files", "mdns4_minimal"
+ criteria []nssCriterion
+}
+
+// standardCriteria reports all specified criteria have the default
+// status actions.
+func (s nssSource) standardCriteria() bool {
+ for i, crit := range s.criteria {
+ if !crit.standardStatusAction(i == len(s.criteria)-1) {
+ return false
+ }
+ }
+ return true
+}
+
+// nssCriterion is the parsed structure of one of the criteria in brackets
+// after an NSS source name.
+type nssCriterion struct {
+ negate bool // if "!" was present
+ status string // e.g. "success", "unavail" (lowercase)
+ action string // e.g. "return", "continue" (lowercase)
+}
+
+// standardStatusAction reports whether c is equivalent to not
+// specifying the criterion at all. last is whether this criteria is the
+// last in the list.
+func (c nssCriterion) standardStatusAction(last bool) bool {
+ if c.negate {
+ return false
+ }
+ var def string
+ switch c.status {
+ case "success":
+ def = "return"
+ case "notfound", "unavail", "tryagain":
+ def = "continue"
+ default:
+ // Unknown status
+ return false
+ }
+ if last && c.action == "return" {
+ return true
+ }
+ return c.action == def
+}
+
+func parseNSSConfFile(file string) *nssConf {
+ f, err := open(file)
+ if err != nil {
+ return &nssConf{err: err}
+ }
+ defer f.close()
+ mtime, _, err := f.stat()
+ if err != nil {
+ return &nssConf{err: err}
+ }
+
+ conf := parseNSSConf(f)
+ conf.mtime = mtime
+ return conf
+}
+
+func parseNSSConf(f *file) *nssConf {
+ conf := new(nssConf)
+ for line, ok := f.readLine(); ok; line, ok = f.readLine() {
+ line = trimSpace(removeComment(line))
+ if len(line) == 0 {
+ continue
+ }
+ colon := bytealg.IndexByteString(line, ':')
+ if colon == -1 {
+ conf.err = errors.New("no colon on line")
+ return conf
+ }
+ db := trimSpace(line[:colon])
+ srcs := line[colon+1:]
+ for {
+ srcs = trimSpace(srcs)
+ if len(srcs) == 0 {
+ break
+ }
+ sp := bytealg.IndexByteString(srcs, ' ')
+ var src string
+ if sp == -1 {
+ src = srcs
+ srcs = "" // done
+ } else {
+ src = srcs[:sp]
+ srcs = trimSpace(srcs[sp+1:])
+ }
+ var criteria []nssCriterion
+ // See if there's a criteria block in brackets.
+ if len(srcs) > 0 && srcs[0] == '[' {
+ bclose := bytealg.IndexByteString(srcs, ']')
+ if bclose == -1 {
+ conf.err = errors.New("unclosed criterion bracket")
+ return conf
+ }
+ var err error
+ criteria, err = parseCriteria(srcs[1:bclose])
+ if err != nil {
+ conf.err = errors.New("invalid criteria: " + srcs[1:bclose])
+ return conf
+ }
+ srcs = srcs[bclose+1:]
+ }
+ if conf.sources == nil {
+ conf.sources = make(map[string][]nssSource)
+ }
+ conf.sources[db] = append(conf.sources[db], nssSource{
+ source: src,
+ criteria: criteria,
+ })
+ }
+ }
+ return conf
+}
+
+// parses "foo=bar !foo=bar"
+func parseCriteria(x string) (c []nssCriterion, err error) {
+ err = foreachField(x, func(f string) error {
+ not := false
+ if len(f) > 0 && f[0] == '!' {
+ not = true
+ f = f[1:]
+ }
+ if len(f) < 3 {
+ return errors.New("criterion too short")
+ }
+ eq := bytealg.IndexByteString(f, '=')
+ if eq == -1 {
+ return errors.New("criterion lacks equal sign")
+ }
+ if hasUpperCase(f) {
+ lower := []byte(f)
+ lowerASCIIBytes(lower)
+ f = string(lower)
+ }
+ c = append(c, nssCriterion{
+ negate: not,
+ status: f[:eq],
+ action: f[eq+1:],
+ })
+ return nil
+ })
+ return
+}
diff --git a/go/src/net/nss_test.go b/go/src/net/nss_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..94e6b5fc0a216ef0309c05dbb90c383889a0a5d3
--- /dev/null
+++ b/go/src/net/nss_test.go
@@ -0,0 +1,172 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
+
+package net
+
+import (
+ "reflect"
+ "testing"
+ "time"
+)
+
+const ubuntuTrustyAvahi = `# /etc/nsswitch.conf
+#
+# Example configuration of GNU Name Service Switch functionality.
+# If you have the libc-doc-reference' and nfo' packages installed, try:
+# nfo libc "Name Service Switch"' for information about this file.
+
+passwd: compat
+group: compat
+shadow: compat
+
+hosts: files mdns4_minimal [NOTFOUND=return] dns mdns4
+networks: files
+
+protocols: db files
+services: db files
+ethers: db files
+rpc: db files
+
+netgroup: nis
+`
+
+func TestParseNSSConf(t *testing.T) {
+ t.Parallel()
+
+ tests := []struct {
+ name string
+ in string
+ want *nssConf
+ }{
+ {
+ name: "no_newline",
+ in: "foo: a b",
+ want: &nssConf{
+ sources: map[string][]nssSource{
+ "foo": {{source: "a"}, {source: "b"}},
+ },
+ },
+ },
+ {
+ name: "newline",
+ in: "foo: a b\n",
+ want: &nssConf{
+ sources: map[string][]nssSource{
+ "foo": {{source: "a"}, {source: "b"}},
+ },
+ },
+ },
+ {
+ name: "whitespace",
+ in: " foo:a b \n",
+ want: &nssConf{
+ sources: map[string][]nssSource{
+ "foo": {{source: "a"}, {source: "b"}},
+ },
+ },
+ },
+ {
+ name: "comment1",
+ in: " foo:a b#c\n",
+ want: &nssConf{
+ sources: map[string][]nssSource{
+ "foo": {{source: "a"}, {source: "b"}},
+ },
+ },
+ },
+ {
+ name: "comment2",
+ in: " foo:a b #c \n",
+ want: &nssConf{
+ sources: map[string][]nssSource{
+ "foo": {{source: "a"}, {source: "b"}},
+ },
+ },
+ },
+ {
+ name: "crit",
+ in: " foo:a b [!a=b X=Y ] c#d \n",
+ want: &nssConf{
+ sources: map[string][]nssSource{
+ "foo": {
+ {source: "a"},
+ {
+ source: "b",
+ criteria: []nssCriterion{
+ {
+ negate: true,
+ status: "a",
+ action: "b",
+ },
+ {
+ status: "x",
+ action: "y",
+ },
+ },
+ },
+ {source: "c"},
+ },
+ },
+ },
+ },
+
+ // Ubuntu Trusty w/ avahi-daemon, libavahi-* etc installed.
+ {
+ name: "ubuntu_trusty_avahi",
+ in: ubuntuTrustyAvahi,
+ want: &nssConf{
+ sources: map[string][]nssSource{
+ "passwd": {{source: "compat"}},
+ "group": {{source: "compat"}},
+ "shadow": {{source: "compat"}},
+ "hosts": {
+ {source: "files"},
+ {
+ source: "mdns4_minimal",
+ criteria: []nssCriterion{
+ {
+ negate: false,
+ status: "notfound",
+ action: "return",
+ },
+ },
+ },
+ {source: "dns"},
+ {source: "mdns4"},
+ },
+ "networks": {{source: "files"}},
+ "protocols": {
+ {source: "db"},
+ {source: "files"},
+ },
+ "services": {
+ {source: "db"},
+ {source: "files"},
+ },
+ "ethers": {
+ {source: "db"},
+ {source: "files"},
+ },
+ "rpc": {
+ {source: "db"},
+ {source: "files"},
+ },
+ "netgroup": {
+ {source: "nis"},
+ },
+ },
+ },
+ },
+ }
+
+ for _, tt := range tests {
+ gotConf := nssStr(t, tt.in)
+ gotConf.mtime = time.Time{} // ignore mtime in comparison
+ if !reflect.DeepEqual(gotConf, tt.want) {
+ t.Errorf("%s: mismatch\n got %#v\nwant %#v", tt.name, gotConf, tt.want)
+ }
+ }
+}
diff --git a/go/src/net/packetconn_test.go b/go/src/net/packetconn_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..e39e7de5d7f6f5bbd0bbff204bd4bbd94ed7275d
--- /dev/null
+++ b/go/src/net/packetconn_test.go
@@ -0,0 +1,149 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements API tests across platforms and should never have a build
+// constraint.
+
+package net
+
+import (
+ "os"
+ "testing"
+)
+
+// The full stack test cases for IPConn have been moved to the
+// following:
+// golang.org/x/net/ipv4
+// golang.org/x/net/ipv6
+// golang.org/x/net/icmp
+
+func packetConnTestData(t *testing.T, network string) ([]byte, func()) {
+ if !testableNetwork(network) {
+ return nil, func() { t.Logf("skipping %s test", network) }
+ }
+ return []byte("PACKETCONN TEST"), nil
+}
+
+func TestPacketConn(t *testing.T) {
+ var packetConnTests = []struct {
+ net string
+ addr1 string
+ addr2 string
+ }{
+ {"udp", "127.0.0.1:0", "127.0.0.1:0"},
+ {"unixgram", testUnixAddr(t), testUnixAddr(t)},
+ }
+
+ closer := func(c PacketConn, net, addr1, addr2 string) {
+ c.Close()
+ switch net {
+ case "unixgram":
+ os.Remove(addr1)
+ os.Remove(addr2)
+ }
+ }
+
+ for _, tt := range packetConnTests {
+ wb, skipOrFatalFn := packetConnTestData(t, tt.net)
+ if skipOrFatalFn != nil {
+ skipOrFatalFn()
+ continue
+ }
+
+ c1, err := ListenPacket(tt.net, tt.addr1)
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer closer(c1, tt.net, tt.addr1, tt.addr2)
+ c1.LocalAddr()
+
+ c2, err := ListenPacket(tt.net, tt.addr2)
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer closer(c2, tt.net, tt.addr1, tt.addr2)
+ c2.LocalAddr()
+ rb2 := make([]byte, 128)
+
+ if _, err := c1.WriteTo(wb, c2.LocalAddr()); err != nil {
+ t.Fatal(err)
+ }
+ if _, _, err := c2.ReadFrom(rb2); err != nil {
+ t.Fatal(err)
+ }
+ if _, err := c2.WriteTo(wb, c1.LocalAddr()); err != nil {
+ t.Fatal(err)
+ }
+ rb1 := make([]byte, 128)
+ if _, _, err := c1.ReadFrom(rb1); err != nil {
+ t.Fatal(err)
+ }
+ }
+}
+
+func TestConnAndPacketConn(t *testing.T) {
+ var packetConnTests = []struct {
+ net string
+ addr1 string
+ addr2 string
+ }{
+ {"udp", "127.0.0.1:0", "127.0.0.1:0"},
+ {"unixgram", testUnixAddr(t), testUnixAddr(t)},
+ }
+
+ closer := func(c PacketConn, net, addr1, addr2 string) {
+ c.Close()
+ switch net {
+ case "unixgram":
+ os.Remove(addr1)
+ os.Remove(addr2)
+ }
+ }
+
+ for _, tt := range packetConnTests {
+ var wb []byte
+ wb, skipOrFatalFn := packetConnTestData(t, tt.net)
+ if skipOrFatalFn != nil {
+ skipOrFatalFn()
+ continue
+ }
+
+ c1, err := ListenPacket(tt.net, tt.addr1)
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer closer(c1, tt.net, tt.addr1, tt.addr2)
+ c1.LocalAddr()
+
+ c2, err := Dial(tt.net, c1.LocalAddr().String())
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer c2.Close()
+ c2.LocalAddr()
+ c2.RemoteAddr()
+
+ if _, err := c2.Write(wb); err != nil {
+ t.Fatal(err)
+ }
+ rb1 := make([]byte, 128)
+ if _, _, err := c1.ReadFrom(rb1); err != nil {
+ t.Fatal(err)
+ }
+ var dst Addr
+ switch tt.net {
+ case "unixgram":
+ continue
+ default:
+ dst = c2.LocalAddr()
+ }
+ if _, err := c1.WriteTo(wb, dst); err != nil {
+ t.Fatal(err)
+ }
+ rb2 := make([]byte, 128)
+ if _, err := c2.Read(rb2); err != nil {
+ t.Fatal(err)
+ }
+ }
+}
diff --git a/go/src/net/parse.go b/go/src/net/parse.go
new file mode 100644
index 0000000000000000000000000000000000000000..106a303dfadae443c7bece173faf1be77df482c3
--- /dev/null
+++ b/go/src/net/parse.go
@@ -0,0 +1,272 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Simple file i/o and string manipulation, to avoid
+// depending on strconv and bufio and strings.
+
+package net
+
+import (
+ "internal/bytealg"
+ "io"
+ "os"
+ "time"
+)
+
+type file struct {
+ file *os.File
+ data []byte
+ atEOF bool
+}
+
+func (f *file) close() { f.file.Close() }
+
+func (f *file) getLineFromData() (s string, ok bool) {
+ data := f.data
+ i := 0
+ for i = 0; i < len(data); i++ {
+ if data[i] == '\n' {
+ s = string(data[0:i])
+ ok = true
+ // move data
+ i++
+ n := len(data) - i
+ copy(data[0:], data[i:])
+ f.data = data[0:n]
+ return
+ }
+ }
+ if f.atEOF && len(f.data) > 0 {
+ // EOF, return all we have
+ s = string(data)
+ f.data = f.data[0:0]
+ ok = true
+ }
+ return
+}
+
+func (f *file) readLine() (s string, ok bool) {
+ if s, ok = f.getLineFromData(); ok {
+ return
+ }
+ if len(f.data) < cap(f.data) {
+ ln := len(f.data)
+ n, err := io.ReadFull(f.file, f.data[ln:cap(f.data)])
+ if n >= 0 {
+ f.data = f.data[0 : ln+n]
+ }
+ if err == io.EOF || err == io.ErrUnexpectedEOF {
+ f.atEOF = true
+ }
+ }
+ s, ok = f.getLineFromData()
+ return
+}
+
+func (f *file) stat() (mtime time.Time, size int64, err error) {
+ st, err := f.file.Stat()
+ if err != nil {
+ return time.Time{}, 0, err
+ }
+ return st.ModTime(), st.Size(), nil
+}
+
+func open(name string) (*file, error) {
+ fd, err := os.Open(name)
+ if err != nil {
+ return nil, err
+ }
+ return &file{fd, make([]byte, 0, 64*1024), false}, nil
+}
+
+func stat(name string) (mtime time.Time, size int64, err error) {
+ st, err := os.Stat(name)
+ if err != nil {
+ return time.Time{}, 0, err
+ }
+ return st.ModTime(), st.Size(), nil
+}
+
+// Count occurrences in s of any bytes in t.
+func countAnyByte(s string, t string) int {
+ n := 0
+ for i := 0; i < len(s); i++ {
+ if bytealg.IndexByteString(t, s[i]) >= 0 {
+ n++
+ }
+ }
+ return n
+}
+
+// Split s at any bytes in t.
+func splitAtBytes(s string, t string) []string {
+ a := make([]string, 1+countAnyByte(s, t))
+ n := 0
+ last := 0
+ for i := 0; i < len(s); i++ {
+ if bytealg.IndexByteString(t, s[i]) >= 0 {
+ if last < i {
+ a[n] = s[last:i]
+ n++
+ }
+ last = i + 1
+ }
+ }
+ if last < len(s) {
+ a[n] = s[last:]
+ n++
+ }
+ return a[0:n]
+}
+
+func getFields(s string) []string { return splitAtBytes(s, " \r\t\n") }
+
+// Bigger than we need, not too big to worry about overflow
+const big = 0xFFFFFF
+
+// Decimal to integer.
+// Returns number, characters consumed, success.
+func dtoi(s string) (n int, i int, ok bool) {
+ n = 0
+ for i = 0; i < len(s) && '0' <= s[i] && s[i] <= '9'; i++ {
+ n = n*10 + int(s[i]-'0')
+ if n >= big {
+ return big, i, false
+ }
+ }
+ if i == 0 {
+ return 0, 0, false
+ }
+ return n, i, true
+}
+
+// Hexadecimal to integer.
+// Returns number, characters consumed, success.
+func xtoi(s string) (n int, i int, ok bool) {
+ n = 0
+ for i = 0; i < len(s); i++ {
+ if '0' <= s[i] && s[i] <= '9' {
+ n *= 16
+ n += int(s[i] - '0')
+ } else if 'a' <= s[i] && s[i] <= 'f' {
+ n *= 16
+ n += int(s[i]-'a') + 10
+ } else if 'A' <= s[i] && s[i] <= 'F' {
+ n *= 16
+ n += int(s[i]-'A') + 10
+ } else {
+ break
+ }
+ if n >= big {
+ return 0, i, false
+ }
+ }
+ if i == 0 {
+ return 0, i, false
+ }
+ return n, i, true
+}
+
+// xtoi2 converts the next two hex digits of s into a byte.
+// If s is longer than 2 bytes then the third byte must be e.
+// If the first two bytes of s are not hex digits or the third byte
+// does not match e, false is returned.
+func xtoi2(s string, e byte) (byte, bool) {
+ if len(s) > 2 && s[2] != e {
+ return 0, false
+ }
+ n, ei, ok := xtoi(s[:2])
+ return byte(n), ok && ei == 2
+}
+
+// hasUpperCase tells whether the given string contains at least one upper-case.
+func hasUpperCase(s string) bool {
+ for i := range s {
+ if 'A' <= s[i] && s[i] <= 'Z' {
+ return true
+ }
+ }
+ return false
+}
+
+// lowerASCIIBytes makes x ASCII lowercase in-place.
+func lowerASCIIBytes(x []byte) {
+ for i, b := range x {
+ if 'A' <= b && b <= 'Z' {
+ x[i] += 'a' - 'A'
+ }
+ }
+}
+
+// lowerASCII returns the ASCII lowercase version of b.
+func lowerASCII(b byte) byte {
+ if 'A' <= b && b <= 'Z' {
+ return b + ('a' - 'A')
+ }
+ return b
+}
+
+// trimSpace returns x without any leading or trailing ASCII whitespace.
+func trimSpace(x string) string {
+ for len(x) > 0 && isSpace(x[0]) {
+ x = x[1:]
+ }
+ for len(x) > 0 && isSpace(x[len(x)-1]) {
+ x = x[:len(x)-1]
+ }
+ return x
+}
+
+// isSpace reports whether b is an ASCII space character.
+func isSpace(b byte) bool {
+ return b == ' ' || b == '\t' || b == '\n' || b == '\r'
+}
+
+// removeComment returns line, removing any '#' byte and any following
+// bytes.
+func removeComment(line string) string {
+ if i := bytealg.IndexByteString(line, '#'); i != -1 {
+ return line[:i]
+ }
+ return line
+}
+
+// foreachField runs fn on each non-empty run of non-space bytes in x.
+// It returns the first non-nil error returned by fn.
+func foreachField(x string, fn func(field string) error) error {
+ x = trimSpace(x)
+ for len(x) > 0 {
+ sp := bytealg.IndexByteString(x, ' ')
+ if sp == -1 {
+ return fn(x)
+ }
+ if field := trimSpace(x[:sp]); len(field) > 0 {
+ if err := fn(field); err != nil {
+ return err
+ }
+ }
+ x = trimSpace(x[sp+1:])
+ }
+ return nil
+}
+
+// stringsHasSuffixFold reports whether s ends in suffix,
+// ASCII-case-insensitively.
+func stringsHasSuffixFold(s, suffix string) bool {
+ return len(s) >= len(suffix) && stringsEqualFold(s[len(s)-len(suffix):], suffix)
+}
+
+// stringsEqualFold is strings.EqualFold, ASCII only. It reports whether s and t
+// are equal, ASCII-case-insensitively.
+func stringsEqualFold(s, t string) bool {
+ if len(s) != len(t) {
+ return false
+ }
+ for i := 0; i < len(s); i++ {
+ if lowerASCII(s[i]) != lowerASCII(t[i]) {
+ return false
+ }
+ }
+ return true
+}
diff --git a/go/src/net/parse_test.go b/go/src/net/parse_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..e58d9541544425d656fe27afe7109e850a2eec45
--- /dev/null
+++ b/go/src/net/parse_test.go
@@ -0,0 +1,75 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "bufio"
+ "os"
+ "runtime"
+ "testing"
+)
+
+func TestReadLine(t *testing.T) {
+ // /etc/services file does not exist on android, plan9, windows, or wasip1
+ // where it would be required to be mounted from the host file system.
+ switch runtime.GOOS {
+ case "android", "plan9", "windows", "wasip1":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+ filename := "/etc/services" // a nice big file
+
+ fd, err := os.Open(filename)
+ if err != nil {
+ // The file is missing even on some Unix systems.
+ t.Skipf("skipping because failed to open /etc/services: %v", err)
+ }
+ defer fd.Close()
+ br := bufio.NewReader(fd)
+
+ file, err := open(filename)
+ if file == nil {
+ t.Fatal(err)
+ }
+ defer file.close()
+
+ lineno := 1
+ byteno := 0
+ for {
+ bline, berr := br.ReadString('\n')
+ if n := len(bline); n > 0 {
+ bline = bline[0 : n-1]
+ }
+ line, ok := file.readLine()
+ if (berr != nil) != !ok || bline != line {
+ t.Fatalf("%s:%d (#%d)\nbufio => %q, %v\nnet => %q, %v", filename, lineno, byteno, bline, berr, line, ok)
+ }
+ if !ok {
+ break
+ }
+ lineno++
+ byteno += len(line) + 1
+ }
+}
+
+func TestDtoi(t *testing.T) {
+ for _, tt := range []struct {
+ in string
+ out int
+ off int
+ ok bool
+ }{
+ {"", 0, 0, false},
+ {"0", 0, 1, true},
+ {"65536", 65536, 5, true},
+ {"123456789", big, 8, false},
+ {"-0", 0, 0, false},
+ {"-1234", 0, 0, false},
+ } {
+ n, i, ok := dtoi(tt.in)
+ if n != tt.out || i != tt.off || ok != tt.ok {
+ t.Errorf("got %d, %d, %v; want %d, %d, %v", n, i, ok, tt.out, tt.off, tt.ok)
+ }
+ }
+}
diff --git a/go/src/net/pipe.go b/go/src/net/pipe.go
new file mode 100644
index 0000000000000000000000000000000000000000..69955e4617c23a79a440b81e99c0e327adf7ceed
--- /dev/null
+++ b/go/src/net/pipe.go
@@ -0,0 +1,238 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "io"
+ "os"
+ "sync"
+ "time"
+)
+
+// pipeDeadline is an abstraction for handling timeouts.
+type pipeDeadline struct {
+ mu sync.Mutex // Guards timer and cancel
+ timer *time.Timer
+ cancel chan struct{} // Must be non-nil
+}
+
+func makePipeDeadline() pipeDeadline {
+ return pipeDeadline{cancel: make(chan struct{})}
+}
+
+// set sets the point in time when the deadline will time out.
+// A timeout event is signaled by closing the channel returned by waiter.
+// Once a timeout has occurred, the deadline can be refreshed by specifying a
+// t value in the future.
+//
+// A zero value for t prevents timeout.
+func (d *pipeDeadline) set(t time.Time) {
+ d.mu.Lock()
+ defer d.mu.Unlock()
+
+ if d.timer != nil && !d.timer.Stop() {
+ <-d.cancel // Wait for the timer callback to finish and close cancel
+ }
+ d.timer = nil
+
+ // Time is zero, then there is no deadline.
+ closed := isClosedChan(d.cancel)
+ if t.IsZero() {
+ if closed {
+ d.cancel = make(chan struct{})
+ }
+ return
+ }
+
+ // Time in the future, setup a timer to cancel in the future.
+ if dur := time.Until(t); dur > 0 {
+ if closed {
+ d.cancel = make(chan struct{})
+ }
+ d.timer = time.AfterFunc(dur, func() {
+ close(d.cancel)
+ })
+ return
+ }
+
+ // Time in the past, so close immediately.
+ if !closed {
+ close(d.cancel)
+ }
+}
+
+// wait returns a channel that is closed when the deadline is exceeded.
+func (d *pipeDeadline) wait() chan struct{} {
+ d.mu.Lock()
+ defer d.mu.Unlock()
+ return d.cancel
+}
+
+func isClosedChan(c <-chan struct{}) bool {
+ select {
+ case <-c:
+ return true
+ default:
+ return false
+ }
+}
+
+type pipeAddr struct{}
+
+func (pipeAddr) Network() string { return "pipe" }
+func (pipeAddr) String() string { return "pipe" }
+
+type pipe struct {
+ wrMu sync.Mutex // Serialize Write operations
+
+ // Used by local Read to interact with remote Write.
+ // Successful receive on rdRx is always followed by send on rdTx.
+ rdRx <-chan []byte
+ rdTx chan<- int
+
+ // Used by local Write to interact with remote Read.
+ // Successful send on wrTx is always followed by receive on wrRx.
+ wrTx chan<- []byte
+ wrRx <-chan int
+
+ once sync.Once // Protects closing localDone
+ localDone chan struct{}
+ remoteDone <-chan struct{}
+
+ readDeadline pipeDeadline
+ writeDeadline pipeDeadline
+}
+
+// Pipe creates a synchronous, in-memory, full duplex
+// network connection; both ends implement the [Conn] interface.
+// Reads on one end are matched with writes on the other,
+// copying data directly between the two; there is no internal
+// buffering.
+func Pipe() (Conn, Conn) {
+ cb1 := make(chan []byte)
+ cb2 := make(chan []byte)
+ cn1 := make(chan int)
+ cn2 := make(chan int)
+ done1 := make(chan struct{})
+ done2 := make(chan struct{})
+
+ p1 := &pipe{
+ rdRx: cb1, rdTx: cn1,
+ wrTx: cb2, wrRx: cn2,
+ localDone: done1, remoteDone: done2,
+ readDeadline: makePipeDeadline(),
+ writeDeadline: makePipeDeadline(),
+ }
+ p2 := &pipe{
+ rdRx: cb2, rdTx: cn2,
+ wrTx: cb1, wrRx: cn1,
+ localDone: done2, remoteDone: done1,
+ readDeadline: makePipeDeadline(),
+ writeDeadline: makePipeDeadline(),
+ }
+ return p1, p2
+}
+
+func (*pipe) LocalAddr() Addr { return pipeAddr{} }
+func (*pipe) RemoteAddr() Addr { return pipeAddr{} }
+
+func (p *pipe) Read(b []byte) (int, error) {
+ n, err := p.read(b)
+ if err != nil && err != io.EOF && err != io.ErrClosedPipe {
+ err = &OpError{Op: "read", Net: "pipe", Err: err}
+ }
+ return n, err
+}
+
+func (p *pipe) read(b []byte) (n int, err error) {
+ switch {
+ case isClosedChan(p.localDone):
+ return 0, io.ErrClosedPipe
+ case isClosedChan(p.remoteDone):
+ return 0, io.EOF
+ case isClosedChan(p.readDeadline.wait()):
+ return 0, os.ErrDeadlineExceeded
+ }
+
+ select {
+ case bw := <-p.rdRx:
+ nr := copy(b, bw)
+ p.rdTx <- nr
+ return nr, nil
+ case <-p.localDone:
+ return 0, io.ErrClosedPipe
+ case <-p.remoteDone:
+ return 0, io.EOF
+ case <-p.readDeadline.wait():
+ return 0, os.ErrDeadlineExceeded
+ }
+}
+
+func (p *pipe) Write(b []byte) (int, error) {
+ n, err := p.write(b)
+ if err != nil && err != io.ErrClosedPipe {
+ err = &OpError{Op: "write", Net: "pipe", Err: err}
+ }
+ return n, err
+}
+
+func (p *pipe) write(b []byte) (n int, err error) {
+ switch {
+ case isClosedChan(p.localDone):
+ return 0, io.ErrClosedPipe
+ case isClosedChan(p.remoteDone):
+ return 0, io.ErrClosedPipe
+ case isClosedChan(p.writeDeadline.wait()):
+ return 0, os.ErrDeadlineExceeded
+ }
+
+ p.wrMu.Lock() // Ensure entirety of b is written together
+ defer p.wrMu.Unlock()
+ for once := true; once || len(b) > 0; once = false {
+ select {
+ case p.wrTx <- b:
+ nw := <-p.wrRx
+ b = b[nw:]
+ n += nw
+ case <-p.localDone:
+ return n, io.ErrClosedPipe
+ case <-p.remoteDone:
+ return n, io.ErrClosedPipe
+ case <-p.writeDeadline.wait():
+ return n, os.ErrDeadlineExceeded
+ }
+ }
+ return n, nil
+}
+
+func (p *pipe) SetDeadline(t time.Time) error {
+ if isClosedChan(p.localDone) || isClosedChan(p.remoteDone) {
+ return io.ErrClosedPipe
+ }
+ p.readDeadline.set(t)
+ p.writeDeadline.set(t)
+ return nil
+}
+
+func (p *pipe) SetReadDeadline(t time.Time) error {
+ if isClosedChan(p.localDone) || isClosedChan(p.remoteDone) {
+ return io.ErrClosedPipe
+ }
+ p.readDeadline.set(t)
+ return nil
+}
+
+func (p *pipe) SetWriteDeadline(t time.Time) error {
+ if isClosedChan(p.localDone) || isClosedChan(p.remoteDone) {
+ return io.ErrClosedPipe
+ }
+ p.writeDeadline.set(t)
+ return nil
+}
+
+func (p *pipe) Close() error {
+ p.once.Do(func() { close(p.localDone) })
+ return nil
+}
diff --git a/go/src/net/pipe_test.go b/go/src/net/pipe_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..9cc24148ca26fe0173412ae378b38c51fa47b1a8
--- /dev/null
+++ b/go/src/net/pipe_test.go
@@ -0,0 +1,49 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net_test
+
+import (
+ "io"
+ "net"
+ "testing"
+ "time"
+
+ "golang.org/x/net/nettest"
+)
+
+func TestPipe(t *testing.T) {
+ nettest.TestConn(t, func() (c1, c2 net.Conn, stop func(), err error) {
+ c1, c2 = net.Pipe()
+ stop = func() {
+ c1.Close()
+ c2.Close()
+ }
+ return
+ })
+}
+
+func TestPipeCloseError(t *testing.T) {
+ c1, c2 := net.Pipe()
+ c1.Close()
+
+ if _, err := c1.Read(nil); err != io.ErrClosedPipe {
+ t.Errorf("c1.Read() = %v, want io.ErrClosedPipe", err)
+ }
+ if _, err := c1.Write(nil); err != io.ErrClosedPipe {
+ t.Errorf("c1.Write() = %v, want io.ErrClosedPipe", err)
+ }
+ if err := c1.SetDeadline(time.Time{}); err != io.ErrClosedPipe {
+ t.Errorf("c1.SetDeadline() = %v, want io.ErrClosedPipe", err)
+ }
+ if _, err := c2.Read(nil); err != io.EOF {
+ t.Errorf("c2.Read() = %v, want io.EOF", err)
+ }
+ if _, err := c2.Write(nil); err != io.ErrClosedPipe {
+ t.Errorf("c2.Write() = %v, want io.ErrClosedPipe", err)
+ }
+ if err := c2.SetDeadline(time.Time{}); err != io.ErrClosedPipe {
+ t.Errorf("c2.SetDeadline() = %v, want io.ErrClosedPipe", err)
+ }
+}
diff --git a/go/src/net/platform_plan9_test.go b/go/src/net/platform_plan9_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..e1ca0aadae1238782bd0ed467fab5b92d882a660
--- /dev/null
+++ b/go/src/net/platform_plan9_test.go
@@ -0,0 +1,9 @@
+// Copyright 2025 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+func supportsUnixSocket() bool {
+ return false
+}
diff --git a/go/src/net/platform_test.go b/go/src/net/platform_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..f8317104d03ed1dbab75762c9d898af2996c7d8f
--- /dev/null
+++ b/go/src/net/platform_test.go
@@ -0,0 +1,161 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "internal/testenv"
+ "os"
+ "runtime"
+ "strings"
+ "testing"
+)
+
+// testableNetwork reports whether network is testable on the current
+// platform configuration.
+func testableNetwork(network string) bool {
+ net, _, _ := strings.Cut(network, ":")
+ switch net {
+ case "ip+nopriv":
+ case "ip", "ip4", "ip6":
+ switch runtime.GOOS {
+ case "plan9":
+ return false
+ default:
+ if os.Getuid() != 0 {
+ return false
+ }
+ }
+ case "unixgram":
+ switch runtime.GOOS {
+ case "windows":
+ return false
+ default:
+ return supportsUnixSocket()
+ }
+ case "unix":
+ return supportsUnixSocket()
+ case "unixpacket":
+ switch runtime.GOOS {
+ case "aix", "android", "darwin", "ios", "plan9", "windows":
+ return false
+ }
+ }
+ switch net {
+ case "tcp4", "udp4", "ip4":
+ if !supportsIPv4() {
+ return false
+ }
+ case "tcp6", "udp6", "ip6":
+ if !supportsIPv6() {
+ return false
+ }
+ }
+ return true
+}
+
+// testableAddress reports whether address of network is testable on
+// the current platform configuration.
+func testableAddress(network, address string) bool {
+ switch net, _, _ := strings.Cut(network, ":"); net {
+ case "unix", "unixgram", "unixpacket":
+ // Abstract unix domain sockets, a Linux-ism.
+ if address[0] == '@' && runtime.GOOS != "linux" {
+ return false
+ }
+ }
+ return true
+}
+
+// testableListenArgs reports whether arguments are testable on the
+// current platform configuration.
+func testableListenArgs(network, address, client string) bool {
+ if !testableNetwork(network) || !testableAddress(network, address) {
+ return false
+ }
+
+ var err error
+ var addr Addr
+ switch net, _, _ := strings.Cut(network, ":"); net {
+ case "tcp", "tcp4", "tcp6":
+ addr, err = ResolveTCPAddr("tcp", address)
+ case "udp", "udp4", "udp6":
+ addr, err = ResolveUDPAddr("udp", address)
+ case "ip", "ip4", "ip6":
+ addr, err = ResolveIPAddr("ip", address)
+ default:
+ return true
+ }
+ if err != nil {
+ return false
+ }
+ var ip IP
+ var wildcard bool
+ switch addr := addr.(type) {
+ case *TCPAddr:
+ ip = addr.IP
+ wildcard = addr.isWildcard()
+ case *UDPAddr:
+ ip = addr.IP
+ wildcard = addr.isWildcard()
+ case *IPAddr:
+ ip = addr.IP
+ wildcard = addr.isWildcard()
+ }
+
+ // Test wildcard IP addresses.
+ if wildcard && !testenv.HasExternalNetwork() {
+ return false
+ }
+
+ // Test functionality of IPv4 communication using AF_INET and
+ // IPv6 communication using AF_INET6 sockets.
+ if !supportsIPv4() && ip.To4() != nil {
+ return false
+ }
+ if !supportsIPv6() && ip.To16() != nil && ip.To4() == nil {
+ return false
+ }
+ cip := ParseIP(client)
+ if cip != nil {
+ if !supportsIPv4() && cip.To4() != nil {
+ return false
+ }
+ if !supportsIPv6() && cip.To16() != nil && cip.To4() == nil {
+ return false
+ }
+ }
+
+ // Test functionality of IPv4 communication using AF_INET6
+ // sockets.
+ if !supportsIPv4map() && supportsIPv4() && (network == "tcp" || network == "udp" || network == "ip") && wildcard {
+ // At this point, we prefer IPv4 when ip is nil.
+ // See favoriteAddrFamily for further information.
+ if ip.To16() != nil && ip.To4() == nil && cip.To4() != nil { // a pair of IPv6 server and IPv4 client
+ return false
+ }
+ if (ip.To4() != nil || ip == nil) && cip.To16() != nil && cip.To4() == nil { // a pair of IPv4 server and IPv6 client
+ return false
+ }
+ }
+
+ return true
+}
+
+func condFatalf(t *testing.T, network string, format string, args ...any) {
+ t.Helper()
+ // A few APIs like File and Read/WriteMsg{UDP,IP} are not
+ // fully implemented yet on Plan 9 and Windows.
+ switch runtime.GOOS {
+ case "windows", "js", "wasip1":
+ if network == "file+net" {
+ t.Logf(format, args...)
+ return
+ }
+ case "plan9":
+ t.Logf(format, args...)
+ return
+ }
+ t.Fatalf(format, args...)
+}
diff --git a/go/src/net/platform_unix_test.go b/go/src/net/platform_unix_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..b6b3a5549de86509f0351fc8ca58b2a25947796a
--- /dev/null
+++ b/go/src/net/platform_unix_test.go
@@ -0,0 +1,40 @@
+// Copyright 2025 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || js || wasip1
+
+package net
+
+import (
+ "os/exec"
+ "runtime"
+ "strconv"
+)
+
+var unixEnabledOnAIX bool
+
+func init() {
+ if runtime.GOOS == "aix" {
+ // Unix network isn't properly working on AIX 7.2 with
+ // Technical Level < 2.
+ // The information is retrieved only once in this init()
+ // instead of everytime testableNetwork is called.
+ out, _ := exec.Command("oslevel", "-s").Output()
+ if len(out) >= len("7200-XX-ZZ-YYMM") { // AIX 7.2, Tech Level XX, Service Pack ZZ, date YYMM
+ aixVer := string(out[:4])
+ tl, _ := strconv.Atoi(string(out[5:7]))
+ unixEnabledOnAIX = aixVer > "7200" || (aixVer == "7200" && tl >= 2)
+ }
+ }
+}
+
+func supportsUnixSocket() bool {
+ switch runtime.GOOS {
+ case "android", "ios":
+ return false
+ case "aix":
+ return unixEnabledOnAIX
+ }
+ return true
+}
diff --git a/go/src/net/platform_windows_test.go b/go/src/net/platform_windows_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..ec2c861e80142e1a1edc685e73485ebbad40bc21
--- /dev/null
+++ b/go/src/net/platform_windows_test.go
@@ -0,0 +1,11 @@
+// Copyright 2025 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import "internal/syscall/windows"
+
+func supportsUnixSocket() bool {
+ return windows.SupportUnixSocket()
+}
diff --git a/go/src/net/port.go b/go/src/net/port.go
new file mode 100644
index 0000000000000000000000000000000000000000..32e76286193c23ca2a196e9ddceaab33b7f0f5ac
--- /dev/null
+++ b/go/src/net/port.go
@@ -0,0 +1,62 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+// parsePort parses service as a decimal integer and returns the
+// corresponding value as port. It is the caller's responsibility to
+// parse service as a non-decimal integer when needsLookup is true.
+//
+// Some system resolvers will return a valid port number when given a number
+// over 65536 (see https://golang.org/issues/11715). Alas, the parser
+// can't bail early on numbers > 65536. Therefore reasonably large/small
+// numbers are parsed in full and rejected if invalid.
+func parsePort(service string) (port int, needsLookup bool) {
+ if service == "" {
+ // Lock in the legacy behavior that an empty string
+ // means port 0. See golang.org/issue/13610.
+ return 0, false
+ }
+ const (
+ max = uint32(1<<32 - 1)
+ cutoff = uint32(1 << 30)
+ )
+ neg := false
+ if service[0] == '+' {
+ service = service[1:]
+ } else if service[0] == '-' {
+ neg = true
+ service = service[1:]
+ }
+ var n uint32
+ for _, d := range service {
+ if '0' <= d && d <= '9' {
+ d -= '0'
+ } else {
+ return 0, true
+ }
+ if n >= cutoff {
+ n = max
+ break
+ }
+ n *= 10
+ nn := n + uint32(d)
+ if nn < n || nn > max {
+ n = max
+ break
+ }
+ n = nn
+ }
+ if !neg && n >= cutoff {
+ port = int(cutoff - 1)
+ } else if neg && n > cutoff {
+ port = int(cutoff)
+ } else {
+ port = int(n)
+ }
+ if neg {
+ port = -port
+ }
+ return port, false
+}
diff --git a/go/src/net/port_test.go b/go/src/net/port_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..e0bdb4247d31f51485f65dc53e49101b4154e290
--- /dev/null
+++ b/go/src/net/port_test.go
@@ -0,0 +1,52 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import "testing"
+
+var parsePortTests = []struct {
+ service string
+ port int
+ needsLookup bool
+}{
+ {"", 0, false},
+
+ // Decimal number literals
+ {"-1073741825", -1 << 30, false},
+ {"-1073741824", -1 << 30, false},
+ {"-1073741823", -(1<<30 - 1), false},
+ {"-123456789", -123456789, false},
+ {"-1", -1, false},
+ {"-0", 0, false},
+ {"0", 0, false},
+ {"+0", 0, false},
+ {"+1", 1, false},
+ {"65535", 65535, false},
+ {"65536", 65536, false},
+ {"123456789", 123456789, false},
+ {"1073741822", 1<<30 - 2, false},
+ {"1073741823", 1<<30 - 1, false},
+ {"1073741824", 1<<30 - 1, false},
+ {"1073741825", 1<<30 - 1, false},
+
+ // Others
+ {"abc", 0, true},
+ {"9pfs", 0, true},
+ {"123badport", 0, true},
+ {"bad123port", 0, true},
+ {"badport123", 0, true},
+ {"123456789badport", 0, true},
+ {"-2147483649badport", 0, true},
+ {"2147483649badport", 0, true},
+}
+
+func TestParsePort(t *testing.T) {
+ // The following test cases are cribbed from the strconv
+ for _, tt := range parsePortTests {
+ if port, needsLookup := parsePort(tt.service); port != tt.port || needsLookup != tt.needsLookup {
+ t.Errorf("parsePort(%q) = %d, %t; want %d, %t", tt.service, port, needsLookup, tt.port, tt.needsLookup)
+ }
+ }
+}
diff --git a/go/src/net/port_unix.go b/go/src/net/port_unix.go
new file mode 100644
index 0000000000000000000000000000000000000000..df73dbabb3c25fa5c754980e4f53c5d85815629a
--- /dev/null
+++ b/go/src/net/port_unix.go
@@ -0,0 +1,57 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix || js || wasip1
+
+// Read system port mappings from /etc/services
+
+package net
+
+import (
+ "internal/bytealg"
+ "sync"
+)
+
+var onceReadServices sync.Once
+
+func readServices() {
+ file, err := open("/etc/services")
+ if err != nil {
+ return
+ }
+ defer file.close()
+
+ for line, ok := file.readLine(); ok; line, ok = file.readLine() {
+ // "http 80/tcp www www-http # World Wide Web HTTP"
+ if i := bytealg.IndexByteString(line, '#'); i >= 0 {
+ line = line[:i]
+ }
+ f := getFields(line)
+ if len(f) < 2 {
+ continue
+ }
+ portnet := f[1] // "80/tcp"
+ port, j, ok := dtoi(portnet)
+ if !ok || port <= 0 || j >= len(portnet) || portnet[j] != '/' {
+ continue
+ }
+ netw := portnet[j+1:] // "tcp"
+ m, ok1 := services[netw]
+ if !ok1 {
+ m = make(map[string]int)
+ services[netw] = m
+ }
+ for i := 0; i < len(f); i++ {
+ if i != 1 { // f[1] was port/net
+ m[f[i]] = port
+ }
+ }
+ }
+}
+
+// goLookupPort is the native Go implementation of LookupPort.
+func goLookupPort(network, service string) (port int, err error) {
+ onceReadServices.Do(readServices)
+ return lookupPortMap(network, service)
+}
diff --git a/go/src/net/protoconn_test.go b/go/src/net/protoconn_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..a617470580d5288b517fa3753d874dfb8193952d
--- /dev/null
+++ b/go/src/net/protoconn_test.go
@@ -0,0 +1,352 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements API tests across platforms and will never have a build
+// tag.
+
+package net
+
+import (
+ "internal/testenv"
+ "os"
+ "runtime"
+ "testing"
+ "time"
+)
+
+// The full stack test cases for IPConn have been moved to the
+// following:
+// golang.org/x/net/ipv4
+// golang.org/x/net/ipv6
+// golang.org/x/net/icmp
+
+func TestTCPListenerSpecificMethods(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+
+ la, err := ResolveTCPAddr("tcp4", "127.0.0.1:0")
+ if err != nil {
+ t.Fatal(err)
+ }
+ ln, err := ListenTCP("tcp4", la)
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer ln.Close()
+ ln.Addr()
+ mustSetDeadline(t, ln.SetDeadline, 30*time.Nanosecond)
+
+ if c, err := ln.Accept(); err != nil {
+ if !err.(Error).Timeout() {
+ t.Fatal(err)
+ }
+ } else {
+ c.Close()
+ }
+ if c, err := ln.AcceptTCP(); err != nil {
+ if !err.(Error).Timeout() {
+ t.Fatal(err)
+ }
+ } else {
+ c.Close()
+ }
+
+ if f, err := ln.File(); err != nil {
+ condFatalf(t, "file+net", "%v", err)
+ } else {
+ f.Close()
+ }
+}
+
+func TestTCPConnSpecificMethods(t *testing.T) {
+ la, err := ResolveTCPAddr("tcp4", "127.0.0.1:0")
+ if err != nil {
+ t.Fatal(err)
+ }
+ ln, err := ListenTCP("tcp4", la)
+ if err != nil {
+ t.Fatal(err)
+ }
+ ch := make(chan error, 1)
+ handler := func(ls *localServer, ln Listener) { ls.transponder(ls.Listener, ch) }
+ ls := (&streamListener{Listener: ln}).newLocalServer()
+ defer ls.teardown()
+ if err := ls.buildup(handler); err != nil {
+ t.Fatal(err)
+ }
+
+ ra, err := ResolveTCPAddr("tcp4", ls.Listener.Addr().String())
+ if err != nil {
+ t.Fatal(err)
+ }
+ c, err := DialTCP("tcp4", nil, ra)
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer c.Close()
+ c.SetKeepAlive(false)
+ c.SetKeepAlivePeriod(3 * time.Second)
+ c.SetLinger(0)
+ c.SetNoDelay(false)
+ c.LocalAddr()
+ c.RemoteAddr()
+ c.SetDeadline(time.Now().Add(someTimeout))
+ c.SetReadDeadline(time.Now().Add(someTimeout))
+ c.SetWriteDeadline(time.Now().Add(someTimeout))
+
+ if _, err := c.Write([]byte("TCPCONN TEST")); err != nil {
+ t.Fatal(err)
+ }
+ rb := make([]byte, 128)
+ if _, err := c.Read(rb); err != nil {
+ t.Fatal(err)
+ }
+
+ for err := range ch {
+ t.Error(err)
+ }
+}
+
+func TestUDPConnSpecificMethods(t *testing.T) {
+ la, err := ResolveUDPAddr("udp4", "127.0.0.1:0")
+ if err != nil {
+ t.Fatal(err)
+ }
+ c, err := ListenUDP("udp4", la)
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer c.Close()
+ c.LocalAddr()
+ c.RemoteAddr()
+ c.SetDeadline(time.Now().Add(someTimeout))
+ c.SetReadDeadline(time.Now().Add(someTimeout))
+ c.SetWriteDeadline(time.Now().Add(someTimeout))
+ c.SetReadBuffer(2048)
+ c.SetWriteBuffer(2048)
+
+ wb := []byte("UDPCONN TEST")
+ rb := make([]byte, 128)
+ if _, err := c.WriteToUDP(wb, c.LocalAddr().(*UDPAddr)); err != nil {
+ t.Fatal(err)
+ }
+ if _, _, err := c.ReadFromUDP(rb); err != nil {
+ t.Fatal(err)
+ }
+ if _, _, err := c.WriteMsgUDP(wb, nil, c.LocalAddr().(*UDPAddr)); err != nil {
+ condFatalf(t, c.LocalAddr().Network(), "%v", err)
+ }
+ if _, _, _, _, err := c.ReadMsgUDP(rb, nil); err != nil {
+ condFatalf(t, c.LocalAddr().Network(), "%v", err)
+ }
+
+ if f, err := c.File(); err != nil {
+ condFatalf(t, "file+net", "%v", err)
+ } else {
+ f.Close()
+ }
+
+ defer func() {
+ if p := recover(); p != nil {
+ t.Fatalf("panicked: %v", p)
+ }
+ }()
+
+ c.WriteToUDP(wb, nil)
+ c.WriteMsgUDP(wb, nil, nil)
+}
+
+func TestIPConnSpecificMethods(t *testing.T) {
+ if !testableNetwork("ip4") {
+ t.Skip("skipping: ip4 not supported")
+ }
+
+ la, err := ResolveIPAddr("ip4", "127.0.0.1")
+ if err != nil {
+ t.Fatal(err)
+ }
+ c, err := ListenIP("ip4:icmp", la)
+ if testenv.SyscallIsNotSupported(err) {
+ // May be inside a container that disallows creating a socket or
+ // not running as root.
+ t.Skipf("skipping: %v", err)
+ } else if err != nil {
+ t.Fatal(err)
+ }
+ defer c.Close()
+ c.LocalAddr()
+ c.RemoteAddr()
+ c.SetDeadline(time.Now().Add(someTimeout))
+ c.SetReadDeadline(time.Now().Add(someTimeout))
+ c.SetWriteDeadline(time.Now().Add(someTimeout))
+ c.SetReadBuffer(2048)
+ c.SetWriteBuffer(2048)
+
+ if f, err := c.File(); err != nil {
+ condFatalf(t, "file+net", "%v", err)
+ } else {
+ f.Close()
+ }
+
+ defer func() {
+ if p := recover(); p != nil {
+ t.Fatalf("panicked: %v", p)
+ }
+ }()
+
+ wb := []byte("IPCONN TEST")
+ c.WriteToIP(wb, nil)
+ c.WriteMsgIP(wb, nil, nil)
+}
+
+func TestUnixListenerSpecificMethods(t *testing.T) {
+ if !testableNetwork("unix") {
+ t.Skip("unix test")
+ }
+
+ addr := testUnixAddr(t)
+ la, err := ResolveUnixAddr("unix", addr)
+ if err != nil {
+ t.Fatal(err)
+ }
+ ln, err := ListenUnix("unix", la)
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer ln.Close()
+ defer os.Remove(addr)
+ ln.Addr()
+ mustSetDeadline(t, ln.SetDeadline, 30*time.Nanosecond)
+
+ if c, err := ln.Accept(); err != nil {
+ if !err.(Error).Timeout() {
+ t.Fatal(err)
+ }
+ } else {
+ c.Close()
+ }
+ if c, err := ln.AcceptUnix(); err != nil {
+ if !err.(Error).Timeout() {
+ t.Fatal(err)
+ }
+ } else {
+ c.Close()
+ }
+
+ if f, err := ln.File(); err != nil {
+ condFatalf(t, "file+net", "%v", err)
+ } else {
+ f.Close()
+ }
+}
+
+func TestUnixConnSpecificMethods(t *testing.T) {
+ if !testableNetwork("unixgram") {
+ t.Skip("unixgram test")
+ }
+
+ addr1, addr2, addr3 := testUnixAddr(t), testUnixAddr(t), testUnixAddr(t)
+
+ a1, err := ResolveUnixAddr("unixgram", addr1)
+ if err != nil {
+ t.Fatal(err)
+ }
+ c1, err := DialUnix("unixgram", a1, nil)
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer c1.Close()
+ defer os.Remove(addr1)
+ c1.LocalAddr()
+ c1.RemoteAddr()
+ c1.SetDeadline(time.Now().Add(someTimeout))
+ c1.SetReadDeadline(time.Now().Add(someTimeout))
+ c1.SetWriteDeadline(time.Now().Add(someTimeout))
+ c1.SetReadBuffer(2048)
+ c1.SetWriteBuffer(2048)
+
+ a2, err := ResolveUnixAddr("unixgram", addr2)
+ if err != nil {
+ t.Fatal(err)
+ }
+ c2, err := DialUnix("unixgram", a2, nil)
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer c2.Close()
+ defer os.Remove(addr2)
+ c2.LocalAddr()
+ c2.RemoteAddr()
+ c2.SetDeadline(time.Now().Add(someTimeout))
+ c2.SetReadDeadline(time.Now().Add(someTimeout))
+ c2.SetWriteDeadline(time.Now().Add(someTimeout))
+ c2.SetReadBuffer(2048)
+ c2.SetWriteBuffer(2048)
+
+ a3, err := ResolveUnixAddr("unixgram", addr3)
+ if err != nil {
+ t.Fatal(err)
+ }
+ c3, err := ListenUnixgram("unixgram", a3)
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer c3.Close()
+ defer os.Remove(addr3)
+ c3.LocalAddr()
+ c3.RemoteAddr()
+ c3.SetDeadline(time.Now().Add(someTimeout))
+ c3.SetReadDeadline(time.Now().Add(someTimeout))
+ c3.SetWriteDeadline(time.Now().Add(someTimeout))
+ c3.SetReadBuffer(2048)
+ c3.SetWriteBuffer(2048)
+
+ wb := []byte("UNIXCONN TEST")
+ rb1 := make([]byte, 128)
+ rb2 := make([]byte, 128)
+ rb3 := make([]byte, 128)
+ if _, _, err := c1.WriteMsgUnix(wb, nil, a2); err != nil {
+ t.Fatal(err)
+ }
+ if _, _, _, _, err := c2.ReadMsgUnix(rb2, nil); err != nil {
+ t.Fatal(err)
+ }
+ if _, err := c2.WriteToUnix(wb, a1); err != nil {
+ t.Fatal(err)
+ }
+ if _, _, err := c1.ReadFromUnix(rb1); err != nil {
+ t.Fatal(err)
+ }
+ if _, err := c3.WriteToUnix(wb, a1); err != nil {
+ t.Fatal(err)
+ }
+ if _, _, err := c1.ReadFromUnix(rb1); err != nil {
+ t.Fatal(err)
+ }
+ if _, err := c2.WriteToUnix(wb, a3); err != nil {
+ t.Fatal(err)
+ }
+ if _, _, err := c3.ReadFromUnix(rb3); err != nil {
+ t.Fatal(err)
+ }
+
+ if f, err := c1.File(); err != nil {
+ condFatalf(t, "file+net", "%v", err)
+ } else {
+ f.Close()
+ }
+
+ defer func() {
+ if p := recover(); p != nil {
+ t.Fatalf("panicked: %v", p)
+ }
+ }()
+
+ c1.WriteToUnix(wb, nil)
+ c1.WriteMsgUnix(wb, nil, nil)
+ c3.WriteToUnix(wb, nil)
+ c3.WriteMsgUnix(wb, nil, nil)
+}
diff --git a/go/src/net/rawconn.go b/go/src/net/rawconn.go
new file mode 100644
index 0000000000000000000000000000000000000000..19228e94ed9e44eb9ff50f7f778518da294be887
--- /dev/null
+++ b/go/src/net/rawconn.go
@@ -0,0 +1,107 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "internal/poll"
+ "runtime"
+ "syscall"
+)
+
+// BUG(tmm1): On Windows, the Write method of syscall.RawConn
+// does not integrate with the runtime's network poller. It cannot
+// wait for the connection to become writeable, and does not respect
+// deadlines. If the user-provided callback returns false, the Write
+// method will fail immediately.
+
+// BUG(mikio): On JS and Plan 9, the Control, Read and Write
+// methods of syscall.RawConn are not implemented.
+
+type rawConn struct {
+ fd *netFD
+}
+
+func (c *rawConn) ok() bool { return c != nil && c.fd != nil }
+
+func (c *rawConn) Control(f func(uintptr)) error {
+ if !c.ok() {
+ return syscall.EINVAL
+ }
+ err := c.fd.pfd.RawControl(f)
+ runtime.KeepAlive(c.fd)
+ if err != nil {
+ err = &OpError{Op: "raw-control", Net: c.fd.net, Source: nil, Addr: c.fd.laddr, Err: err}
+ }
+ return err
+}
+
+func (c *rawConn) Read(f func(uintptr) bool) error {
+ if !c.ok() {
+ return syscall.EINVAL
+ }
+ err := c.fd.pfd.RawRead(f)
+ runtime.KeepAlive(c.fd)
+ if err != nil {
+ err = &OpError{Op: "raw-read", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+ }
+ return err
+}
+
+func (c *rawConn) Write(f func(uintptr) bool) error {
+ if !c.ok() {
+ return syscall.EINVAL
+ }
+ err := c.fd.pfd.RawWrite(f)
+ runtime.KeepAlive(c.fd)
+ if err != nil {
+ err = &OpError{Op: "raw-write", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
+ }
+ return err
+}
+
+// PollFD returns the poll.FD of the underlying connection.
+//
+// Other packages in std that also import [internal/poll] (such as os)
+// can use a type assertion to access this extension method so that
+// they can pass the *poll.FD to functions like poll.Splice.
+//
+// PollFD is not intended for use outside the standard library.
+func (c *rawConn) PollFD() *poll.FD {
+ if !c.ok() {
+ return nil
+ }
+ return &c.fd.pfd
+}
+
+func newRawConn(fd *netFD) *rawConn {
+ return &rawConn{fd: fd}
+}
+
+// Network returns the network type of the underlying connection.
+//
+// Other packages in std that import internal/poll and are unable to
+// import net (such as os) can use a type assertion to access this
+// extension method so that they can distinguish different socket types.
+//
+// Network is not intended for use outside the standard library.
+func (c *rawConn) Network() poll.String {
+ return poll.String(c.fd.net)
+}
+
+type rawListener struct {
+ rawConn
+}
+
+func (l *rawListener) Read(func(uintptr) bool) error {
+ return syscall.EINVAL
+}
+
+func (l *rawListener) Write(func(uintptr) bool) error {
+ return syscall.EINVAL
+}
+
+func newRawListener(fd *netFD) *rawListener {
+ return &rawListener{rawConn{fd: fd}}
+}
diff --git a/go/src/net/rawconn_stub_test.go b/go/src/net/rawconn_stub_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..6d54f2df55be1516af9f562e8f25bd17b813155e
--- /dev/null
+++ b/go/src/net/rawconn_stub_test.go
@@ -0,0 +1,28 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build js || plan9 || wasip1
+
+package net
+
+import (
+ "errors"
+ "syscall"
+)
+
+func readRawConn(c syscall.RawConn, b []byte) (int, error) {
+ return 0, errors.New("not supported")
+}
+
+func writeRawConn(c syscall.RawConn, b []byte) error {
+ return errors.New("not supported")
+}
+
+func controlRawConn(c syscall.RawConn, addr Addr) error {
+ return errors.New("not supported")
+}
+
+func controlOnConnSetup(network string, address string, c syscall.RawConn) error {
+ return nil
+}
diff --git a/go/src/net/rawconn_test.go b/go/src/net/rawconn_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..70b16c411534a1a7ff39288cb65159f4f894350d
--- /dev/null
+++ b/go/src/net/rawconn_test.go
@@ -0,0 +1,209 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "bytes"
+ "runtime"
+ "testing"
+ "time"
+)
+
+func TestRawConnReadWrite(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9", "js", "wasip1":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+
+ t.Run("TCP", func(t *testing.T) {
+ handler := func(ls *localServer, ln Listener) {
+ c, err := ln.Accept()
+ if err != nil {
+ t.Error(err)
+ return
+ }
+ defer c.Close()
+
+ cc, err := ln.(*TCPListener).SyscallConn()
+ if err != nil {
+ t.Fatal(err)
+ }
+ called := false
+ op := func(uintptr) bool {
+ called = true
+ return true
+ }
+ err = cc.Write(op)
+ if err == nil {
+ t.Error("Write should return an error")
+ }
+ if called {
+ t.Error("Write shouldn't call op")
+ }
+ called = false
+ err = cc.Read(op)
+ if err == nil {
+ t.Error("Read should return an error")
+ }
+ if called {
+ t.Error("Read shouldn't call op")
+ }
+
+ var b [32]byte
+ n, err := c.Read(b[:])
+ if err != nil {
+ t.Error(err)
+ return
+ }
+ if _, err := c.Write(b[:n]); err != nil {
+ t.Error(err)
+ return
+ }
+ }
+ ls := newLocalServer(t, "tcp")
+ defer ls.teardown()
+ if err := ls.buildup(handler); err != nil {
+ t.Fatal(err)
+ }
+
+ c, err := Dial(ls.Listener.Addr().Network(), ls.Listener.Addr().String())
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer c.Close()
+
+ cc, err := c.(*TCPConn).SyscallConn()
+ if err != nil {
+ t.Fatal(err)
+ }
+ data := []byte("HELLO-R-U-THERE")
+ if err := writeRawConn(cc, data); err != nil {
+ t.Fatal(err)
+ }
+ var b [32]byte
+ n, err := readRawConn(cc, b[:])
+ if err != nil {
+ t.Fatal(err)
+ }
+ if bytes.Compare(b[:n], data) != 0 {
+ t.Fatalf("got %q; want %q", b[:n], data)
+ }
+ })
+ t.Run("Deadline", func(t *testing.T) {
+ switch runtime.GOOS {
+ case "windows":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+
+ ln := newLocalListener(t, "tcp")
+ defer ln.Close()
+
+ c, err := Dial(ln.Addr().Network(), ln.Addr().String())
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer c.Close()
+
+ cc, err := c.(*TCPConn).SyscallConn()
+ if err != nil {
+ t.Fatal(err)
+ }
+ var b [1]byte
+
+ c.SetDeadline(noDeadline)
+ if err := c.SetDeadline(time.Now().Add(-1)); err != nil {
+ t.Fatal(err)
+ }
+ if err = writeRawConn(cc, b[:]); err == nil {
+ t.Fatal("Write should fail")
+ }
+ if perr := parseWriteError(err); perr != nil {
+ t.Error(perr)
+ }
+ if !isDeadlineExceeded(err) {
+ t.Errorf("got %v; want timeout", err)
+ }
+ if _, err = readRawConn(cc, b[:]); err == nil {
+ t.Fatal("Read should fail")
+ }
+ if perr := parseReadError(err); perr != nil {
+ t.Error(perr)
+ }
+ if !isDeadlineExceeded(err) {
+ t.Errorf("got %v; want timeout", err)
+ }
+
+ c.SetReadDeadline(noDeadline)
+ if err := c.SetReadDeadline(time.Now().Add(-1)); err != nil {
+ t.Fatal(err)
+ }
+ if _, err = readRawConn(cc, b[:]); err == nil {
+ t.Fatal("Read should fail")
+ }
+ if perr := parseReadError(err); perr != nil {
+ t.Error(perr)
+ }
+ if !isDeadlineExceeded(err) {
+ t.Errorf("got %v; want timeout", err)
+ }
+
+ c.SetWriteDeadline(noDeadline)
+ if err := c.SetWriteDeadline(time.Now().Add(-1)); err != nil {
+ t.Fatal(err)
+ }
+ if err = writeRawConn(cc, b[:]); err == nil {
+ t.Fatal("Write should fail")
+ }
+ if perr := parseWriteError(err); perr != nil {
+ t.Error(perr)
+ }
+ if !isDeadlineExceeded(err) {
+ t.Errorf("got %v; want timeout", err)
+ }
+ })
+}
+
+func TestRawConnControl(t *testing.T) {
+ switch runtime.GOOS {
+ case "plan9", "js", "wasip1":
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+
+ t.Run("TCP", func(t *testing.T) {
+ ln := newLocalListener(t, "tcp")
+ defer ln.Close()
+
+ cc1, err := ln.(*TCPListener).SyscallConn()
+ if err != nil {
+ t.Fatal(err)
+ }
+ if err := controlRawConn(cc1, ln.Addr()); err != nil {
+ t.Fatal(err)
+ }
+
+ c, err := Dial(ln.Addr().Network(), ln.Addr().String())
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer c.Close()
+
+ cc2, err := c.(*TCPConn).SyscallConn()
+ if err != nil {
+ t.Fatal(err)
+ }
+ if err := controlRawConn(cc2, c.LocalAddr()); err != nil {
+ t.Fatal(err)
+ }
+
+ ln.Close()
+ if err := controlRawConn(cc1, ln.Addr()); err == nil {
+ t.Fatal("Control after Close should fail")
+ }
+ c.Close()
+ if err := controlRawConn(cc2, c.LocalAddr()); err == nil {
+ t.Fatal("Control after Close should fail")
+ }
+ })
+}
diff --git a/go/src/net/rawconn_unix_test.go b/go/src/net/rawconn_unix_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..f11119ed9ec0da04cd04e1ca48452229efa7803c
--- /dev/null
+++ b/go/src/net/rawconn_unix_test.go
@@ -0,0 +1,115 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build unix
+
+package net
+
+import (
+ "errors"
+ "syscall"
+)
+
+func readRawConn(c syscall.RawConn, b []byte) (int, error) {
+ var operr error
+ var n int
+ err := c.Read(func(s uintptr) bool {
+ n, operr = syscall.Read(int(s), b)
+ if operr == syscall.EAGAIN {
+ return false
+ }
+ return true
+ })
+ if err != nil {
+ return n, err
+ }
+ return n, operr
+}
+
+func writeRawConn(c syscall.RawConn, b []byte) error {
+ var operr error
+ err := c.Write(func(s uintptr) bool {
+ _, operr = syscall.Write(int(s), b)
+ if operr == syscall.EAGAIN {
+ return false
+ }
+ return true
+ })
+ if err != nil {
+ return err
+ }
+ return operr
+}
+
+func controlRawConn(c syscall.RawConn, addr Addr) error {
+ var operr error
+ fn := func(s uintptr) {
+ _, operr = syscall.GetsockoptInt(int(s), syscall.SOL_SOCKET, syscall.SO_REUSEADDR)
+ if operr != nil {
+ return
+ }
+ switch addr := addr.(type) {
+ case *TCPAddr:
+ // There's no guarantee that IP-level socket
+ // options work well with dual stack sockets.
+ // A simple solution would be to take a look
+ // at the bound address to the raw connection
+ // and to classify the address family of the
+ // underlying socket by the bound address:
+ //
+ // - When IP.To16() != nil and IP.To4() == nil,
+ // we can assume that the raw connection
+ // consists of an IPv6 socket using only
+ // IPv6 addresses.
+ //
+ // - When IP.To16() == nil and IP.To4() != nil,
+ // the raw connection consists of an IPv4
+ // socket using only IPv4 addresses.
+ //
+ // - Otherwise, the raw connection is a dual
+ // stack socket, an IPv6 socket using IPv6
+ // addresses including IPv4-mapped or
+ // IPv4-embedded IPv6 addresses.
+ if addr.IP.To16() != nil && addr.IP.To4() == nil {
+ operr = syscall.SetsockoptInt(int(s), syscall.IPPROTO_IPV6, syscall.IPV6_UNICAST_HOPS, 1)
+ } else if addr.IP.To16() == nil && addr.IP.To4() != nil {
+ operr = syscall.SetsockoptInt(int(s), syscall.IPPROTO_IP, syscall.IP_TTL, 1)
+ }
+ }
+ }
+ if err := c.Control(fn); err != nil {
+ return err
+ }
+ return operr
+}
+
+func controlOnConnSetup(network string, address string, c syscall.RawConn) error {
+ var operr error
+ var fn func(uintptr)
+ switch network {
+ case "tcp", "udp", "ip":
+ return errors.New("ambiguous network: " + network)
+ case "unix", "unixpacket", "unixgram":
+ fn = func(s uintptr) {
+ _, operr = syscall.GetsockoptInt(int(s), syscall.SOL_SOCKET, syscall.SO_ERROR)
+ }
+ default:
+ switch network[len(network)-1] {
+ case '4':
+ fn = func(s uintptr) {
+ operr = syscall.SetsockoptInt(int(s), syscall.IPPROTO_IP, syscall.IP_TTL, 1)
+ }
+ case '6':
+ fn = func(s uintptr) {
+ operr = syscall.SetsockoptInt(int(s), syscall.IPPROTO_IPV6, syscall.IPV6_UNICAST_HOPS, 1)
+ }
+ default:
+ return errors.New("unknown network: " + network)
+ }
+ }
+ if err := c.Control(fn); err != nil {
+ return err
+ }
+ return operr
+}
diff --git a/go/src/net/rawconn_windows_test.go b/go/src/net/rawconn_windows_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..ebfec3499a2fdd9e0c7eff7ee511b402a3a9589b
--- /dev/null
+++ b/go/src/net/rawconn_windows_test.go
@@ -0,0 +1,121 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+ "errors"
+ "syscall"
+ "unsafe"
+)
+
+func readRawConn(c syscall.RawConn, b []byte) (int, error) {
+ var operr error
+ var n int
+ err := c.Read(func(s uintptr) bool {
+ var read uint32
+ var flags uint32
+ var buf syscall.WSABuf
+ buf.Buf = &b[0]
+ buf.Len = uint32(len(b))
+ operr = syscall.WSARecv(syscall.Handle(s), &buf, 1, &read, &flags, nil, nil)
+ n = int(read)
+ return true
+ })
+ if err != nil {
+ return n, err
+ }
+ return n, operr
+}
+
+func writeRawConn(c syscall.RawConn, b []byte) error {
+ var operr error
+ err := c.Write(func(s uintptr) bool {
+ var written uint32
+ var buf syscall.WSABuf
+ buf.Buf = &b[0]
+ buf.Len = uint32(len(b))
+ operr = syscall.WSASend(syscall.Handle(s), &buf, 1, &written, 0, nil, nil)
+ return true
+ })
+ if err != nil {
+ return err
+ }
+ return operr
+}
+
+func controlRawConn(c syscall.RawConn, addr Addr) error {
+ var operr error
+ fn := func(s uintptr) {
+ var v, l int32
+ l = int32(unsafe.Sizeof(v))
+ operr = syscall.Getsockopt(syscall.Handle(s), syscall.SOL_SOCKET, syscall.SO_REUSEADDR, (*byte)(unsafe.Pointer(&v)), &l)
+ if operr != nil {
+ return
+ }
+ switch addr := addr.(type) {
+ case *TCPAddr:
+ // There's no guarantee that IP-level socket
+ // options work well with dual stack sockets.
+ // A simple solution would be to take a look
+ // at the bound address to the raw connection
+ // and to classify the address family of the
+ // underlying socket by the bound address:
+ //
+ // - When IP.To16() != nil and IP.To4() == nil,
+ // we can assume that the raw connection
+ // consists of an IPv6 socket using only
+ // IPv6 addresses.
+ //
+ // - When IP.To16() == nil and IP.To4() != nil,
+ // the raw connection consists of an IPv4
+ // socket using only IPv4 addresses.
+ //
+ // - Otherwise, the raw connection is a dual
+ // stack socket, an IPv6 socket using IPv6
+ // addresses including IPv4-mapped or
+ // IPv4-embedded IPv6 addresses.
+ if addr.IP.To16() != nil && addr.IP.To4() == nil {
+ operr = syscall.SetsockoptInt(syscall.Handle(s), syscall.IPPROTO_IPV6, syscall.IPV6_UNICAST_HOPS, 1)
+ } else if addr.IP.To16() == nil && addr.IP.To4() != nil {
+ operr = syscall.SetsockoptInt(syscall.Handle(s), syscall.IPPROTO_IP, syscall.IP_TTL, 1)
+ }
+ }
+ }
+ if err := c.Control(fn); err != nil {
+ return err
+ }
+ return operr
+}
+
+func controlOnConnSetup(network string, address string, c syscall.RawConn) error {
+ var operr error
+ var fn func(uintptr)
+ switch network {
+ case "tcp", "udp", "ip":
+ return errors.New("ambiguous network: " + network)
+ case "unix", "unixpacket", "unixgram":
+ fn = func(s uintptr) {
+ const SO_ERROR = 0x1007
+ _, operr = syscall.GetsockoptInt(syscall.Handle(s), syscall.SOL_SOCKET, SO_ERROR)
+ }
+ default:
+ switch network[len(network)-1] {
+ case '4':
+ fn = func(s uintptr) {
+ operr = syscall.SetsockoptInt(syscall.Handle(s), syscall.IPPROTO_IP, syscall.IP_TTL, 1)
+ }
+ case '6':
+ fn = func(s uintptr) {
+ operr = syscall.SetsockoptInt(syscall.Handle(s), syscall.IPPROTO_IPV6, syscall.IPV6_UNICAST_HOPS, 1)
+ }
+ default:
+ return errors.New("unknown network: " + network)
+ }
+ }
+ if err := c.Control(fn); err != nil {
+ return err
+ }
+ return operr
+}
diff --git a/go/test/dwarf/dwarf.dir/main.go b/go/test/dwarf/dwarf.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..175a09c7799734082fe0c69d704d40558f1eb952
--- /dev/null
+++ b/go/test/dwarf/dwarf.dir/main.go
@@ -0,0 +1,32 @@
+// $G $D/$F.go $D/z*.go && $L $F.$A && ./$A.out
+
+// NOTE: This test is not run by 'run.go' and so not run by all.bash.
+// To run this test you must use the ./run shell script.
+
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+func main() {
+F1()
+F2()
+F3()
+F4()
+F5()
+F6()
+F7()
+F8()
+F9()
+F10()
+F11()
+F12()
+F13()
+F14()
+F15()
+F16()
+F17()
+F18()
+F19()
+F20()
+}
diff --git a/go/test/dwarf/dwarf.dir/z1.go b/go/test/dwarf/dwarf.dir/z1.go
new file mode 100644
index 0000000000000000000000000000000000000000..7f163e9a1d97c4f3fb1afd4f3bd57f8415e95b8a
--- /dev/null
+++ b/go/test/dwarf/dwarf.dir/z1.go
@@ -0,0 +1,5 @@
+
+
+//line x1.go:4
+package main
+func F1() {}
diff --git a/go/test/dwarf/dwarf.dir/z10.go b/go/test/dwarf/dwarf.dir/z10.go
new file mode 100644
index 0000000000000000000000000000000000000000..19c70020e0ca367624a97a47be7256aebee1f32b
--- /dev/null
+++ b/go/test/dwarf/dwarf.dir/z10.go
@@ -0,0 +1,6 @@
+
+
+
+//line x10.go:4
+package main
+func F10() {}
diff --git a/go/test/dwarf/dwarf.dir/z11.go b/go/test/dwarf/dwarf.dir/z11.go
new file mode 100644
index 0000000000000000000000000000000000000000..c1d2f9180f11752e79734507a7d041d193c80903
--- /dev/null
+++ b/go/test/dwarf/dwarf.dir/z11.go
@@ -0,0 +1,4 @@
+
+//line x11.go:4
+package main
+func F11() {}
diff --git a/go/test/dwarf/dwarf.dir/z12.go b/go/test/dwarf/dwarf.dir/z12.go
new file mode 100644
index 0000000000000000000000000000000000000000..7455f18946826965937e88b17cf613e9802f410d
--- /dev/null
+++ b/go/test/dwarf/dwarf.dir/z12.go
@@ -0,0 +1,4 @@
+
+//line x12.go:4
+package main
+func F12() {}
diff --git a/go/test/dwarf/dwarf.dir/z13.go b/go/test/dwarf/dwarf.dir/z13.go
new file mode 100644
index 0000000000000000000000000000000000000000..ecb3c4c8c711dba7e20d8fdfaba1f47389a4c720
--- /dev/null
+++ b/go/test/dwarf/dwarf.dir/z13.go
@@ -0,0 +1,4 @@
+
+//line x13.go:4
+package main
+func F13() {}
diff --git a/go/test/dwarf/dwarf.dir/z14.go b/go/test/dwarf/dwarf.dir/z14.go
new file mode 100644
index 0000000000000000000000000000000000000000..134b39b64e2bda6b4bf3fd9da6c4419590546971
--- /dev/null
+++ b/go/test/dwarf/dwarf.dir/z14.go
@@ -0,0 +1,4 @@
+
+//line x14.go:4
+package main
+func F14() {}
diff --git a/go/test/dwarf/dwarf.dir/z15.go b/go/test/dwarf/dwarf.dir/z15.go
new file mode 100644
index 0000000000000000000000000000000000000000..d73819b443ba1b7734261eb0fc9ec7e262022c1f
--- /dev/null
+++ b/go/test/dwarf/dwarf.dir/z15.go
@@ -0,0 +1,4 @@
+
+//line x15.go:4
+package main
+func F15() {}
diff --git a/go/test/dwarf/dwarf.dir/z16.go b/go/test/dwarf/dwarf.dir/z16.go
new file mode 100644
index 0000000000000000000000000000000000000000..6c31651baa891e4ebff5e8a061e05a060fd336f3
--- /dev/null
+++ b/go/test/dwarf/dwarf.dir/z16.go
@@ -0,0 +1,4 @@
+
+//line x16.go:4
+package main
+func F16() {}
diff --git a/go/test/dwarf/dwarf.dir/z17.go b/go/test/dwarf/dwarf.dir/z17.go
new file mode 100644
index 0000000000000000000000000000000000000000..b742d1672606cabc4b9fc31cdb3e039f69481186
--- /dev/null
+++ b/go/test/dwarf/dwarf.dir/z17.go
@@ -0,0 +1,4 @@
+
+//line x17.go:4
+package main
+func F17() {}
diff --git a/go/test/dwarf/dwarf.dir/z18.go b/go/test/dwarf/dwarf.dir/z18.go
new file mode 100644
index 0000000000000000000000000000000000000000..84150ff0a35569ddbdcc45021f3200f377443324
--- /dev/null
+++ b/go/test/dwarf/dwarf.dir/z18.go
@@ -0,0 +1,5 @@
+
+
+//line x18.go:4
+package main
+func F18() {}
diff --git a/go/test/dwarf/dwarf.dir/z19.go b/go/test/dwarf/dwarf.dir/z19.go
new file mode 100644
index 0000000000000000000000000000000000000000..bb2e29684174f20a92926ec988ba9daad1f3d47b
--- /dev/null
+++ b/go/test/dwarf/dwarf.dir/z19.go
@@ -0,0 +1,4 @@
+
+//line x19.go:4
+package main
+func F19() {}
diff --git a/go/test/dwarf/dwarf.dir/z2.go b/go/test/dwarf/dwarf.dir/z2.go
new file mode 100644
index 0000000000000000000000000000000000000000..68bd58257d9a025d26459c9f471278fd6a131e18
--- /dev/null
+++ b/go/test/dwarf/dwarf.dir/z2.go
@@ -0,0 +1,4 @@
+
+//line x2.go:4
+package main
+func F2() {}
diff --git a/go/test/dwarf/dwarf.dir/z20.go b/go/test/dwarf/dwarf.dir/z20.go
new file mode 100644
index 0000000000000000000000000000000000000000..03111e184521d6a5535cc22ca60d42cfef73ca3c
--- /dev/null
+++ b/go/test/dwarf/dwarf.dir/z20.go
@@ -0,0 +1,4 @@
+
+//line x20.go:4
+package main
+func F20() {}
diff --git a/go/test/dwarf/dwarf.dir/z3.go b/go/test/dwarf/dwarf.dir/z3.go
new file mode 100644
index 0000000000000000000000000000000000000000..5e4ad3ae257df2bdbeaee6e382005121e049188d
--- /dev/null
+++ b/go/test/dwarf/dwarf.dir/z3.go
@@ -0,0 +1,4 @@
+
+//line x3.go:4
+package main
+func F3() {}
diff --git a/go/test/dwarf/dwarf.dir/z4.go b/go/test/dwarf/dwarf.dir/z4.go
new file mode 100644
index 0000000000000000000000000000000000000000..1f28465c57714f35f4dbac9b173f32a5b424fa26
--- /dev/null
+++ b/go/test/dwarf/dwarf.dir/z4.go
@@ -0,0 +1,4 @@
+
+//line x4.go:4
+package main
+func F4() {}
diff --git a/go/test/dwarf/dwarf.dir/z5.go b/go/test/dwarf/dwarf.dir/z5.go
new file mode 100644
index 0000000000000000000000000000000000000000..7f4eeb419a35bcec5bdb83f1b767a4032df4570e
--- /dev/null
+++ b/go/test/dwarf/dwarf.dir/z5.go
@@ -0,0 +1,4 @@
+
+//line x5.go:4
+package main
+func F5() {}
diff --git a/go/test/dwarf/dwarf.dir/z6.go b/go/test/dwarf/dwarf.dir/z6.go
new file mode 100644
index 0000000000000000000000000000000000000000..241791dff2b0e003fa592d70e4752689e51e81ef
--- /dev/null
+++ b/go/test/dwarf/dwarf.dir/z6.go
@@ -0,0 +1,4 @@
+
+//line x6.go:4
+package main
+func F6() {}
diff --git a/go/test/dwarf/dwarf.dir/z7.go b/go/test/dwarf/dwarf.dir/z7.go
new file mode 100644
index 0000000000000000000000000000000000000000..68c1ad0c2434ad098addca086e34a88998456372
--- /dev/null
+++ b/go/test/dwarf/dwarf.dir/z7.go
@@ -0,0 +1,4 @@
+
+//line x7.go:4
+package main
+func F7() {}
diff --git a/go/test/dwarf/dwarf.dir/z8.go b/go/test/dwarf/dwarf.dir/z8.go
new file mode 100644
index 0000000000000000000000000000000000000000..16eed32a28d3c4bcca08507f31ff5e3508f68438
--- /dev/null
+++ b/go/test/dwarf/dwarf.dir/z8.go
@@ -0,0 +1,4 @@
+
+//line x8.go:4
+package main
+func F8() {}
diff --git a/go/test/dwarf/dwarf.dir/z9.go b/go/test/dwarf/dwarf.dir/z9.go
new file mode 100644
index 0000000000000000000000000000000000000000..cbb94b4d2beddef80e39ec29177b561725c920a3
--- /dev/null
+++ b/go/test/dwarf/dwarf.dir/z9.go
@@ -0,0 +1,4 @@
+
+//line x9.go:4
+package main
+func F9() {}
diff --git a/go/test/fixedbugs/bug083.dir/bug0.go b/go/test/fixedbugs/bug083.dir/bug0.go
new file mode 100644
index 0000000000000000000000000000000000000000..2f59d81a614d4857ec61f5e786a2e1f0a544bfb4
--- /dev/null
+++ b/go/test/fixedbugs/bug083.dir/bug0.go
@@ -0,0 +1,10 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bug0
+
+type t0 struct {
+}
+
+var V0 t0
diff --git a/go/test/fixedbugs/bug083.dir/bug1.go b/go/test/fixedbugs/bug083.dir/bug1.go
new file mode 100644
index 0000000000000000000000000000000000000000..ea5bcfe205ad5da6f954bd31cdc317537f8ab457
--- /dev/null
+++ b/go/test/fixedbugs/bug083.dir/bug1.go
@@ -0,0 +1,14 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bug1
+
+import "./bug0"
+
+// This is expected to fail--t0 is in package bug0 and should not be
+// visible here in package bug1. The test for failure is in
+// ../bug083.go.
+
+var v1 bug0.t0; // ERROR "bug0"
+
diff --git a/go/test/fixedbugs/bug088.dir/bug0.go b/go/test/fixedbugs/bug088.dir/bug0.go
new file mode 100644
index 0000000000000000000000000000000000000000..7a6e34747f6605013de116965fbbfb8146b21a79
--- /dev/null
+++ b/go/test/fixedbugs/bug088.dir/bug0.go
@@ -0,0 +1,9 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bug0
+
+var V0 func() int;
+var V1 func() (a int);
+var V2 func() (a, b int);
diff --git a/go/test/fixedbugs/bug088.dir/bug1.go b/go/test/fixedbugs/bug088.dir/bug1.go
new file mode 100644
index 0000000000000000000000000000000000000000..2568e37d0209cef4ac690c094c2c2559298fff53
--- /dev/null
+++ b/go/test/fixedbugs/bug088.dir/bug1.go
@@ -0,0 +1,23 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import P "./bug0"
+
+func main() {
+ a0 := P.V0(); // works
+ a1 := P.V1(); // works
+ a2, b2 := P.V2(); // doesn't work
+ _, _, _, _ = a0, a1, a2, b2;
+}
+
+/*
+uetli:~/Source/go1/test/bugs/bug088.dir gri$ 6g bug0.go && 6g bug1.go
+bug1.go:8: shape error across :=
+bug1.go:8: a2: undefined
+bug1.go:8: b2: undefined
+bug1.go:8: illegal types for operand: AS
+ (<(bug0)P.int32>INT32)
+*/
diff --git a/go/test/fixedbugs/bug106.dir/bug0.go b/go/test/fixedbugs/bug106.dir/bug0.go
new file mode 100644
index 0000000000000000000000000000000000000000..7494c580b77df90b611f873c52e4f3431aae6967
--- /dev/null
+++ b/go/test/fixedbugs/bug106.dir/bug0.go
@@ -0,0 +1,7 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bug0
+
+const A = -1
diff --git a/go/test/fixedbugs/bug106.dir/bug1.go b/go/test/fixedbugs/bug106.dir/bug1.go
new file mode 100644
index 0000000000000000000000000000000000000000..eff0d36ed29532d38db96962fa511d18e9f10f93
--- /dev/null
+++ b/go/test/fixedbugs/bug106.dir/bug1.go
@@ -0,0 +1,8 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bug1
+
+import _ "./bug0"
+
diff --git a/go/test/fixedbugs/bug133.dir/bug0.go b/go/test/fixedbugs/bug133.dir/bug0.go
new file mode 100644
index 0000000000000000000000000000000000000000..19a2bfbd4b545214ecd153ea7e7cf12c3a3f76a1
--- /dev/null
+++ b/go/test/fixedbugs/bug133.dir/bug0.go
@@ -0,0 +1,7 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bug0
+
+type T struct { i int }
diff --git a/go/test/fixedbugs/bug133.dir/bug1.go b/go/test/fixedbugs/bug133.dir/bug1.go
new file mode 100644
index 0000000000000000000000000000000000000000..dd59b2f2ec193b58a436c20f501c69c48e599c72
--- /dev/null
+++ b/go/test/fixedbugs/bug133.dir/bug1.go
@@ -0,0 +1,9 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bug1
+
+import "./bug0"
+
+type T struct { t bug0.T }
diff --git a/go/test/fixedbugs/bug133.dir/bug2.go b/go/test/fixedbugs/bug133.dir/bug2.go
new file mode 100644
index 0000000000000000000000000000000000000000..b6184c2e75b03e047441741e301690f16399a03a
--- /dev/null
+++ b/go/test/fixedbugs/bug133.dir/bug2.go
@@ -0,0 +1,16 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bug2
+
+import _ "./bug1"
+import "./bug0"
+
+type T2 struct { t bug0.T }
+
+func fn(p *T2) int {
+ // This reference should be invalid, because bug0.T.i is local
+ // to package bug0 and should not be visible in package bug1.
+ return p.t.i; // ERROR "field|undef"
+}
diff --git a/go/test/fixedbugs/bug160.dir/x.go b/go/test/fixedbugs/bug160.dir/x.go
new file mode 100644
index 0000000000000000000000000000000000000000..2673552d80b8a6a2a6286ff79dc01987d2772ca9
--- /dev/null
+++ b/go/test/fixedbugs/bug160.dir/x.go
@@ -0,0 +1,8 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package x
+
+const Zero = 0.0
+const Ten = 10.0
diff --git a/go/test/fixedbugs/bug160.dir/y.go b/go/test/fixedbugs/bug160.dir/y.go
new file mode 100644
index 0000000000000000000000000000000000000000..428808dd19879a0a56ce39b90a60363a19c914f4
--- /dev/null
+++ b/go/test/fixedbugs/bug160.dir/y.go
@@ -0,0 +1,19 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "os"
+import "./x"
+
+func main() {
+ if x.Zero != 0 {
+ println("x.Zero = ", x.Zero);
+ os.Exit(1);
+ }
+ if x.Ten != 10 {
+ println("x.Ten = ", x.Ten);
+ os.Exit(1);
+ }
+}
diff --git a/go/test/fixedbugs/bug191.dir/a.go b/go/test/fixedbugs/bug191.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..139a8a3a2307d0814548dc16ba0a908e3a280e19
--- /dev/null
+++ b/go/test/fixedbugs/bug191.dir/a.go
@@ -0,0 +1,14 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+var A int
+
+func init() {
+ A = 1
+}
+
+type T int;
+
diff --git a/go/test/fixedbugs/bug191.dir/b.go b/go/test/fixedbugs/bug191.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..36770f6fc99e3f814ec16dd13d4d2f305a81dc98
--- /dev/null
+++ b/go/test/fixedbugs/bug191.dir/b.go
@@ -0,0 +1,13 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+var B int
+
+func init() {
+ B = 2
+}
+
+type V int;
diff --git a/go/test/fixedbugs/bug191.dir/main.go b/go/test/fixedbugs/bug191.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..2d24dd12d5293d97e7891dd52493e2e393e8cc68
--- /dev/null
+++ b/go/test/fixedbugs/bug191.dir/main.go
@@ -0,0 +1,17 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import . "./a"
+import . "./b"
+
+var _ T
+var _ V
+
+func main() {
+ if A != 1 || B != 2 {
+ panic("wrong vars")
+ }
+}
diff --git a/go/test/fixedbugs/bug222.dir/chanbug.go b/go/test/fixedbugs/bug222.dir/chanbug.go
new file mode 100644
index 0000000000000000000000000000000000000000..16920246e00d2056e7978efbb73f1db77848de09
--- /dev/null
+++ b/go/test/fixedbugs/bug222.dir/chanbug.go
@@ -0,0 +1,9 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file
+
+package chanbug
+var C chan<- (chan int)
+var D chan<- func()
+var E func() chan int
+var F func() (func())
diff --git a/go/test/fixedbugs/bug222.dir/chanbug2.go b/go/test/fixedbugs/bug222.dir/chanbug2.go
new file mode 100644
index 0000000000000000000000000000000000000000..b6c416f83458d71b9930d05211ca712f66d034d1
--- /dev/null
+++ b/go/test/fixedbugs/bug222.dir/chanbug2.go
@@ -0,0 +1,7 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file
+
+package Bar
+
+import _ "./chanbug"
diff --git a/go/test/fixedbugs/bug248.dir/bug0.go b/go/test/fixedbugs/bug248.dir/bug0.go
new file mode 100644
index 0000000000000000000000000000000000000000..78433f504d322f0d786a8dbd2a7a72ab08d91c70
--- /dev/null
+++ b/go/test/fixedbugs/bug248.dir/bug0.go
@@ -0,0 +1,13 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file
+
+package p
+
+type T struct {
+ X, Y int
+}
+
+type I interface {
+ M(T)
+}
diff --git a/go/test/fixedbugs/bug248.dir/bug1.go b/go/test/fixedbugs/bug248.dir/bug1.go
new file mode 100644
index 0000000000000000000000000000000000000000..f1db77d2f5d31976a2af3c395e0e158f81400fdc
--- /dev/null
+++ b/go/test/fixedbugs/bug248.dir/bug1.go
@@ -0,0 +1,13 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file
+
+package q
+
+type T struct {
+ X, Y int
+}
+
+type I interface {
+ M(T)
+}
diff --git a/go/test/fixedbugs/bug248.dir/bug2.go b/go/test/fixedbugs/bug248.dir/bug2.go
new file mode 100644
index 0000000000000000000000000000000000000000..92a7974679eae10349fe8f4f7817cbf39fbf28dd
--- /dev/null
+++ b/go/test/fixedbugs/bug248.dir/bug2.go
@@ -0,0 +1,73 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file
+
+package s
+
+import (
+ p0 "./bug0"
+ p1 "./bug1"
+)
+
+// both p0.T and p1.T are struct { X, Y int }.
+
+var v0 p0.T
+var v1 p1.T
+
+// interfaces involving the two
+
+type I0 interface {
+ M(p0.T)
+}
+
+type I1 interface {
+ M(p1.T)
+}
+
+// t0 satisfies I0 and p0.I
+type t0 int
+
+func (t0) M(p0.T) {}
+
+// t1 satisfies I1 and p1.I
+type t1 float64
+
+func (t1) M(p1.T) {}
+
+// check static interface assignments
+var i0 I0 = t0(0) // ok
+var i1 I1 = t1(0) // ok
+
+var i2 I0 = t1(0) // ERROR "does not implement|incompatible"
+var i3 I1 = t0(0) // ERROR "does not implement|incompatible"
+
+var p0i p0.I = t0(0) // ok
+var p1i p1.I = t1(0) // ok
+
+var p0i1 p0.I = t1(0) // ERROR "does not implement|incompatible"
+var p0i2 p1.I = t0(0) // ERROR "does not implement|incompatible"
+
+func foobar() {
+ // check that cannot assign one to the other,
+ // but can convert.
+ v0 = v1 // ERROR "assign|cannot use"
+ v1 = v0 // ERROR "assign|cannot use"
+
+ v0 = p0.T(v1)
+ v1 = p1.T(v0)
+
+ i0 = i1 // ERROR "cannot use|incompatible"
+ i1 = i0 // ERROR "cannot use|incompatible"
+ p0i = i1 // ERROR "cannot use|incompatible"
+ p1i = i0 // ERROR "cannot use|incompatible"
+ i0 = p1i // ERROR "cannot use|incompatible"
+ i1 = p0i // ERROR "cannot use|incompatible"
+ p0i = p1i // ERROR "cannot use|incompatible"
+ p1i = p0i // ERROR "cannot use|incompatible"
+
+ i0 = p0i
+ p0i = i0
+
+ i1 = p1i
+ p1i = i1
+}
diff --git a/go/test/fixedbugs/bug248.dir/bug3.go b/go/test/fixedbugs/bug248.dir/bug3.go
new file mode 100644
index 0000000000000000000000000000000000000000..ba547d64a1074fd63facf0d7416a4284ffcfd40f
--- /dev/null
+++ b/go/test/fixedbugs/bug248.dir/bug3.go
@@ -0,0 +1,105 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file
+
+package main
+
+import (
+ p0 "./bug0"
+ p1 "./bug1"
+
+ "reflect"
+ "strings"
+)
+
+var v0 p0.T
+var v1 p1.T
+
+type I0 interface {
+ M(p0.T)
+}
+
+type I1 interface {
+ M(p1.T)
+}
+
+type t0 int
+
+func (t0) M(p0.T) {}
+
+type t1 float64
+
+func (t1) M(p1.T) {}
+
+var i0 I0 = t0(0) // ok
+var i1 I1 = t1(0) // ok
+
+var p0i p0.I = t0(0) // ok
+var p1i p1.I = t1(0) // ok
+
+func main() {
+ // check that reflect paths are correct,
+ // meaning that reflect data for v0, v1 didn't get confused.
+
+ // path is full (rooted) path name. check suffix for gc, prefix for gccgo
+ if s := reflect.TypeOf(v0).PkgPath(); !strings.HasSuffix(s, "/bug0") && !strings.HasPrefix(s, "bug0") {
+ println("bad v0 path", len(s), s)
+ panic("fail")
+ }
+ if s := reflect.TypeOf(v1).PkgPath(); !strings.HasSuffix(s, "/bug1") && !strings.HasPrefix(s, "bug1") {
+ println("bad v1 path", s)
+ panic("fail")
+ }
+
+ // check that dynamic interface check doesn't get confused
+ var i interface{} = t0(0)
+ if _, ok := i.(I1); ok {
+ println("used t0 as i1")
+ panic("fail")
+ }
+ if _, ok := i.(p1.I); ok {
+ println("used t0 as p1.I")
+ panic("fail")
+ }
+
+ i = t1(1)
+ if _, ok := i.(I0); ok {
+ println("used t1 as i0")
+ panic("fail")
+ }
+ if _, ok := i.(p0.I); ok {
+ println("used t1 as p0.I")
+ panic("fail")
+ }
+
+ // check that type switch works.
+ // the worry is that if p0.T and p1.T have the same hash,
+ // the binary search will handle one of them incorrectly.
+ for j := 0; j < 3; j++ {
+ switch j {
+ case 0:
+ i = p0.T{}
+ case 1:
+ i = p1.T{}
+ case 2:
+ i = 3.14
+ }
+ switch i.(type) {
+ case p0.T:
+ if j != 0 {
+ println("type switch p0.T")
+ panic("fail")
+ }
+ case p1.T:
+ if j != 1 {
+ println("type switch p1.T")
+ panic("fail")
+ }
+ default:
+ if j != 2 {
+ println("type switch default", j)
+ panic("fail")
+ }
+ }
+ }
+}
diff --git a/go/test/fixedbugs/bug282.dir/p1.go b/go/test/fixedbugs/bug282.dir/p1.go
new file mode 100644
index 0000000000000000000000000000000000000000..0f7422c0ba0e2d68c30a28e4c702785daa2523f5
--- /dev/null
+++ b/go/test/fixedbugs/bug282.dir/p1.go
@@ -0,0 +1,10 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p1
+
+type T struct {
+ f func() "x"
+}
+
diff --git a/go/test/fixedbugs/bug282.dir/p2.go b/go/test/fixedbugs/bug282.dir/p2.go
new file mode 100644
index 0000000000000000000000000000000000000000..f614507946602c75adfc1d76ba41b1908c7b9da7
--- /dev/null
+++ b/go/test/fixedbugs/bug282.dir/p2.go
@@ -0,0 +1,8 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p2
+
+import _ "./p1"
+
diff --git a/go/test/fixedbugs/bug306.dir/p1.go b/go/test/fixedbugs/bug306.dir/p1.go
new file mode 100644
index 0000000000000000000000000000000000000000..b28551807d663b885f3ff0e167651869367be5c3
--- /dev/null
+++ b/go/test/fixedbugs/bug306.dir/p1.go
@@ -0,0 +1,9 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p1
+
+type T <-chan int
+var x = make(chan T)
+
diff --git a/go/test/fixedbugs/bug306.dir/p2.go b/go/test/fixedbugs/bug306.dir/p2.go
new file mode 100644
index 0000000000000000000000000000000000000000..f614507946602c75adfc1d76ba41b1908c7b9da7
--- /dev/null
+++ b/go/test/fixedbugs/bug306.dir/p2.go
@@ -0,0 +1,8 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p2
+
+import _ "./p1"
+
diff --git a/go/test/fixedbugs/bug313.dir/a.go b/go/test/fixedbugs/bug313.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..335f84d4ba16b2e1fa2ae0c178429289ef991801
--- /dev/null
+++ b/go/test/fixedbugs/bug313.dir/a.go
@@ -0,0 +1,11 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "fmt"
+
+func a() {
+ fmt.DoesNotExist() // ERROR "undefined"
+}
diff --git a/go/test/fixedbugs/bug313.dir/b.go b/go/test/fixedbugs/bug313.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..26e6413702fc3bcbff42d2765aeaa2c08783d88d
--- /dev/null
+++ b/go/test/fixedbugs/bug313.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import . "fmt"
+
+func b() {
+ Println()
+}
diff --git a/go/test/fixedbugs/bug322.dir/lib.go b/go/test/fixedbugs/bug322.dir/lib.go
new file mode 100644
index 0000000000000000000000000000000000000000..0de56d3d649354e5196e2b2af18f520516083149
--- /dev/null
+++ b/go/test/fixedbugs/bug322.dir/lib.go
@@ -0,0 +1,15 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package lib
+
+type T struct {
+ x int // non-exported field
+}
+
+func (t T) M() {
+}
+
+func (t *T) PM() {
+}
diff --git a/go/test/fixedbugs/bug322.dir/main.go b/go/test/fixedbugs/bug322.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..f403c7d32e2ac187a054100c679d97aa1c73a851
--- /dev/null
+++ b/go/test/fixedbugs/bug322.dir/main.go
@@ -0,0 +1,40 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./lib"
+
+type I interface {
+ M()
+}
+
+type PI interface {
+ PM()
+}
+
+func main() {
+ var t lib.T
+ t.M()
+ t.PM()
+
+ // This is still an error.
+ // var i1 I = t
+ // i1.M()
+
+ // This combination is illegal because
+ // PM requires a pointer receiver.
+ // var pi1 PI = t
+ // pi1.PM()
+
+ var pt = &t
+ pt.M()
+ pt.PM()
+
+ var i2 I = pt
+ i2.M()
+
+ var pi2 PI = pt
+ pi2.PM()
+}
diff --git a/go/test/fixedbugs/bug324.dir/p.go b/go/test/fixedbugs/bug324.dir/p.go
new file mode 100644
index 0000000000000000000000000000000000000000..d1e3b991aada1d9775328bde4054610fd2255681
--- /dev/null
+++ b/go/test/fixedbugs/bug324.dir/p.go
@@ -0,0 +1,15 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+type Exported interface {
+ private()
+}
+
+type Implementation struct{}
+
+func (p *Implementation) private() { println("p.Implementation.private()") }
+
+var X = new(Implementation)
diff --git a/go/test/fixedbugs/bug324.dir/prog.go b/go/test/fixedbugs/bug324.dir/prog.go
new file mode 100644
index 0000000000000000000000000000000000000000..3ab61f3eb5e87fecc23e7ffc92bd380f67ad5fc4
--- /dev/null
+++ b/go/test/fixedbugs/bug324.dir/prog.go
@@ -0,0 +1,53 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./p"
+)
+
+type Exported interface {
+ private()
+}
+
+type Implementation struct{}
+
+func (p *Implementation) private() {}
+
+
+func main() {
+ // nothing unusual here
+ var x Exported
+ x = new(Implementation)
+ x.private() // main.Implementation.private()
+
+ // same here - should be and is legal
+ var px p.Exported
+ px = p.X
+
+ // this assignment is correctly illegal:
+ // px.private undefined (cannot refer to unexported field or method private)
+ // px.private()
+
+ // this assignment is correctly illegal:
+ // *Implementation does not implement p.Exported (missing p.private method)
+ // px = new(Implementation)
+
+ // this assignment is correctly illegal:
+ // p.Exported does not implement Exported (missing private method)
+ // x = px
+
+ // this assignment unexpectedly compiles and then executes
+ defer func() {
+ recover()
+ }()
+ x = px.(Exported)
+
+ println("should not get this far")
+
+ // this is a legitimate call, but because of the previous assignment,
+ // it invokes the method private in p!
+ x.private() // p.Implementation.private()
+}
diff --git a/go/test/fixedbugs/bug335.dir/a.go b/go/test/fixedbugs/bug335.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..6ecc5c45ef89224d7f2a20272dc83b200c540e31
--- /dev/null
+++ b/go/test/fixedbugs/bug335.dir/a.go
@@ -0,0 +1,11 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type T interface{}
+
+func f() T { return nil }
+
+var Foo T = f()
diff --git a/go/test/fixedbugs/bug335.dir/b.go b/go/test/fixedbugs/bug335.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..a7735a82e41e57a53d1e026127bc9b787c9a67fb
--- /dev/null
+++ b/go/test/fixedbugs/bug335.dir/b.go
@@ -0,0 +1,9 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+var Bar = a.Foo
diff --git a/go/test/fixedbugs/bug345.dir/io.go b/go/test/fixedbugs/bug345.dir/io.go
new file mode 100644
index 0000000000000000000000000000000000000000..ca7a5092e9f849cbe04e70c23bf86b90646b4f66
--- /dev/null
+++ b/go/test/fixedbugs/bug345.dir/io.go
@@ -0,0 +1,15 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package io
+
+type Writer interface {
+ WrongWrite()
+}
+
+type SectionReader struct {
+ X int
+}
+
+func SR(*SectionReader) {}
diff --git a/go/test/fixedbugs/bug345.dir/main.go b/go/test/fixedbugs/bug345.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..a53d3e8586ed553a73d847d6b8493a95bcb9a513
--- /dev/null
+++ b/go/test/fixedbugs/bug345.dir/main.go
@@ -0,0 +1,29 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "bufio"
+ goio "io"
+
+ "./io"
+)
+
+func main() {
+ // The errors here complain that io.X != io.X
+ // for different values of io so they should be
+ // showing the full import path, which for the
+ // "./io" import is really ..../go/test/io.
+ // For example:
+ //
+ // main.go:25: cannot use w (type "/Users/rsc/g/go/test/fixedbugs/bug345.dir/io".Writer) as type "io".Writer in function argument:
+ // io.Writer does not implement io.Writer (missing Write method)
+ // main.go:27: cannot use &x (type *"io".SectionReader) as type *"/Users/rsc/g/go/test/fixedbugs/bug345.dir/io".SectionReader in function argument
+
+ var w io.Writer
+ bufio.NewWriter(w) // ERROR "[\w.]+[^.]/io|has incompatible type|cannot use"
+ var x goio.SectionReader
+ io.SR(&x) // ERROR "[\w.]+[^.]/io|has incompatible type|cannot use"
+}
diff --git a/go/test/fixedbugs/bug367.dir/p.go b/go/test/fixedbugs/bug367.dir/p.go
new file mode 100644
index 0000000000000000000000000000000000000000..2028f740ccdbe959c0501bf45cef7cb27a0e4935
--- /dev/null
+++ b/go/test/fixedbugs/bug367.dir/p.go
@@ -0,0 +1,19 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file
+
+package p
+
+type T struct{ x int }
+type S struct{}
+
+func (p *S) get() {
+}
+
+type I interface {
+ get()
+}
+
+func F(i I) {
+ i.get()
+}
diff --git a/go/test/fixedbugs/bug367.dir/prog.go b/go/test/fixedbugs/bug367.dir/prog.go
new file mode 100644
index 0000000000000000000000000000000000000000..c278e4dd95ff78799c91ca1032886dfb9ff6d9b0
--- /dev/null
+++ b/go/test/fixedbugs/bug367.dir/prog.go
@@ -0,0 +1,28 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file
+
+package main
+
+import (
+ "./p"
+)
+
+type T struct{ *p.S }
+type I interface {
+ get()
+}
+
+func main() {
+ var t T
+ p.F(t)
+ var x interface{} = t
+ _, ok := x.(I)
+ if ok {
+ panic("should not satisfy main.I")
+ }
+ _, ok = x.(p.I)
+ if !ok {
+ panic("should satisfy p.I")
+ }
+}
diff --git a/go/test/fixedbugs/bug369.dir/main.go b/go/test/fixedbugs/bug369.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..03b53a5b90d29c579ad3f20401270e11a141f09d
--- /dev/null
+++ b/go/test/fixedbugs/bug369.dir/main.go
@@ -0,0 +1,55 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "flag"
+ "os"
+ "runtime"
+ "testing"
+
+ fast "./fast"
+ slow "./slow"
+)
+
+var buf = make([]byte, 1048576)
+
+func BenchmarkFastNonASCII(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ fast.NonASCII(buf, 0)
+ }
+}
+
+func BenchmarkSlowNonASCII(b *testing.B) {
+ for i := 0; i < b.N; i++ {
+ slow.NonASCII(buf, 0)
+ }
+}
+
+func main() {
+ testing.Init()
+ os.Args = []string{os.Args[0], "-test.benchtime=100ms"}
+ flag.Parse()
+
+ rslow := testing.Benchmark(BenchmarkSlowNonASCII)
+ rfast := testing.Benchmark(BenchmarkFastNonASCII)
+ tslow := rslow.NsPerOp()
+ tfast := rfast.NsPerOp()
+
+ // Optimization should be good for at least 2x, but be forgiving.
+ // On the ARM simulator we see closer to 1.5x.
+ speedup := float64(tslow) / float64(tfast)
+ want := 1.8
+ if runtime.GOARCH == "arm" {
+ want = 1.3
+ }
+ if speedup < want {
+ // TODO(rsc): doesn't work on linux-amd64 or darwin-amd64 builders, nor on
+ // a Lenovo x200 (linux-amd64) laptop.
+ // println("fast:", tfast, "slow:", tslow, "speedup:", speedup, "want:", want)
+ // println("not fast enough")
+ // os.Exit(1)
+ }
+}
diff --git a/go/test/fixedbugs/bug369.dir/pkg.go b/go/test/fixedbugs/bug369.dir/pkg.go
new file mode 100644
index 0000000000000000000000000000000000000000..9964347250948886b45eb066a59e7bfb20e14c63
--- /dev/null
+++ b/go/test/fixedbugs/bug369.dir/pkg.go
@@ -0,0 +1,15 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package pkg
+
+func NonASCII(b []byte, i int) int {
+ for i = 0; i < len(b); i++ {
+ if b[i] >= 0x80 {
+ break
+ }
+ }
+ return i
+}
+
diff --git a/go/test/fixedbugs/bug377.dir/one.go b/go/test/fixedbugs/bug377.dir/one.go
new file mode 100644
index 0000000000000000000000000000000000000000..e29b813a481d01fedae3e6db0eb4340e1b53e16e
--- /dev/null
+++ b/go/test/fixedbugs/bug377.dir/one.go
@@ -0,0 +1,10 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file
+
+package one
+
+func Foo() (n int64, _ *int) {
+ return 42, nil
+}
+
diff --git a/go/test/fixedbugs/bug377.dir/two.go b/go/test/fixedbugs/bug377.dir/two.go
new file mode 100644
index 0000000000000000000000000000000000000000..2a10812d56d0a558febeaf87b3b0ffdf53b7db1a
--- /dev/null
+++ b/go/test/fixedbugs/bug377.dir/two.go
@@ -0,0 +1,8 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file
+
+package two
+
+import _ "./one"
+
diff --git a/go/test/fixedbugs/bug382.dir/pkg.go b/go/test/fixedbugs/bug382.dir/pkg.go
new file mode 100644
index 0000000000000000000000000000000000000000..92fe4e335a1815d33728a8bb20c58c100e2f53de
--- /dev/null
+++ b/go/test/fixedbugs/bug382.dir/pkg.go
@@ -0,0 +1,7 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package pkg
+type T struct {}
+var E T
diff --git a/go/test/fixedbugs/bug382.dir/prog.go b/go/test/fixedbugs/bug382.dir/prog.go
new file mode 100644
index 0000000000000000000000000000000000000000..b74a82d8241c6f19109d005501e86ab1ea03de1b
--- /dev/null
+++ b/go/test/fixedbugs/bug382.dir/prog.go
@@ -0,0 +1,13 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file
+
+// Issue 2529
+
+package main
+
+import "./pkg"
+
+var x = pkg.E
+
+var fo = struct{ F pkg.T }{F: x}
diff --git a/go/test/fixedbugs/bug392.dir/one.go b/go/test/fixedbugs/bug392.dir/one.go
new file mode 100644
index 0000000000000000000000000000000000000000..aba8649b5b1d387a32fc96c85048a4c85356bce9
--- /dev/null
+++ b/go/test/fixedbugs/bug392.dir/one.go
@@ -0,0 +1,43 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Functions that the inliner exported incorrectly.
+
+package one
+
+type T int
+
+// Issue 2678
+func F1(T *T) bool { return T == nil }
+
+// Issue 2682.
+func F2(c chan int) bool { return c == (<-chan int)(nil) }
+
+// Use of single named return value.
+func F3() (ret []int) { return append(ret, 1) }
+
+// Call of inlined method with blank receiver.
+func (_ *T) M() int { return 1 }
+func (t *T) MM() int { return t.M() }
+
+
+// One more like issue 2678
+type S struct { x, y int }
+type U []S
+
+func F4(S int) U { return U{{S,S}} }
+
+func F5() []*S {
+ return []*S{ {1,2}, { 3, 4} }
+}
+
+func F6(S int) *U {
+ return &U{{S,S}}
+}
+
+// Bug in the fix.
+
+type PB struct { x int }
+
+func (t *PB) Reset() { *t = PB{} }
diff --git a/go/test/fixedbugs/bug392.dir/pkg2.go b/go/test/fixedbugs/bug392.dir/pkg2.go
new file mode 100644
index 0000000000000000000000000000000000000000..2ee41f0251072d9d19e5c9696709bf931ee0f39c
--- /dev/null
+++ b/go/test/fixedbugs/bug392.dir/pkg2.go
@@ -0,0 +1,25 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Use the functions in one.go so that the inlined
+// forms get type-checked.
+
+package pkg2
+
+import "./one"
+
+func use() {
+ one.F1(nil)
+ one.F2(nil)
+ one.F3()
+ one.F4(1)
+
+ var t *one.T
+ t.M()
+ t.MM()
+}
+
+var V = []one.PB{{}, {}}
+
+func F() *one.PB
diff --git a/go/test/fixedbugs/bug392.dir/pkg3.go b/go/test/fixedbugs/bug392.dir/pkg3.go
new file mode 100644
index 0000000000000000000000000000000000000000..1403798bd30a4fe473e1a465ff33696f00ca75d3
--- /dev/null
+++ b/go/test/fixedbugs/bug392.dir/pkg3.go
@@ -0,0 +1,13 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Use the functions in pkg2.go so that the inlined
+// forms get type-checked.
+
+package pkg3
+
+import "./pkg2"
+
+var x = pkg2.F()
+var v = pkg2.V
diff --git a/go/test/fixedbugs/bug396.dir/one.go b/go/test/fixedbugs/bug396.dir/one.go
new file mode 100644
index 0000000000000000000000000000000000000000..66eba63f5c1dfd3614f10cc1370409f3dd017533
--- /dev/null
+++ b/go/test/fixedbugs/bug396.dir/one.go
@@ -0,0 +1,10 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package one
+
+// Issue 2687
+type T struct { int }
+
+func New(i int) T { return T{i} }
diff --git a/go/test/fixedbugs/bug396.dir/two.go b/go/test/fixedbugs/bug396.dir/two.go
new file mode 100644
index 0000000000000000000000000000000000000000..9152bec2545b73f7598d008d048960ff87d5a95d
--- /dev/null
+++ b/go/test/fixedbugs/bug396.dir/two.go
@@ -0,0 +1,14 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Use the functions in one.go so that the inlined
+// forms get type-checked.
+
+package two
+
+import "./one"
+
+func use() {
+ _ = one.New(1)
+}
\ No newline at end of file
diff --git a/go/test/fixedbugs/bug404.dir/one.go b/go/test/fixedbugs/bug404.dir/one.go
new file mode 100644
index 0000000000000000000000000000000000000000..9fc47707891a5467dae3b95515648c0a637302e7
--- /dev/null
+++ b/go/test/fixedbugs/bug404.dir/one.go
@@ -0,0 +1,19 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package one
+
+type T1 int
+type T2 []T1
+type T3 T2
+
+func F1(T2) {
+}
+
+func (p *T1) M1() T3 {
+ return nil
+}
+
+func (p T3) M2() {
+}
diff --git a/go/test/fixedbugs/bug404.dir/two.go b/go/test/fixedbugs/bug404.dir/two.go
new file mode 100644
index 0000000000000000000000000000000000000000..0c70a23a9e4b5a2aaf3332114ed0b72750bf150d
--- /dev/null
+++ b/go/test/fixedbugs/bug404.dir/two.go
@@ -0,0 +1,12 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// The gccgo compiler would fail on the import statement.
+// two.go:10:13: error: use of undefined type ‘one.T2’
+
+package two
+
+import "./one"
+
+var V one.T3
diff --git a/go/test/fixedbugs/bug407.dir/one.go b/go/test/fixedbugs/bug407.dir/one.go
new file mode 100644
index 0000000000000000000000000000000000000000..c85b077b66cdefca1c152808fb38edfa9660584c
--- /dev/null
+++ b/go/test/fixedbugs/bug407.dir/one.go
@@ -0,0 +1,20 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package one
+
+// Issue 2877
+type T struct {
+ f func(t *T, arg int)
+ g func(t T, arg int)
+}
+
+func (t *T) foo(arg int) {}
+func (t T) goo(arg int) {}
+
+func (t *T) F() { t.f = (*T).foo }
+func (t *T) G() { t.g = T.goo }
+
+
+
diff --git a/go/test/fixedbugs/bug407.dir/two.go b/go/test/fixedbugs/bug407.dir/two.go
new file mode 100644
index 0000000000000000000000000000000000000000..640305c654167039f53c9245e62401e5e71bd325
--- /dev/null
+++ b/go/test/fixedbugs/bug407.dir/two.go
@@ -0,0 +1,15 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Use the functions in one.go so that the inlined
+// forms get type-checked.
+
+package two
+
+import "./one"
+
+func use() {
+ var r one.T
+ r.F()
+}
diff --git a/go/test/fixedbugs/bug414.dir/p1.go b/go/test/fixedbugs/bug414.dir/p1.go
new file mode 100644
index 0000000000000000000000000000000000000000..143e600073f010ac118ab6e84f43f614108d259e
--- /dev/null
+++ b/go/test/fixedbugs/bug414.dir/p1.go
@@ -0,0 +1,21 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p1
+
+import "fmt"
+
+type Fer interface {
+ f() string
+}
+
+type Object struct{}
+
+func (this *Object) f() string {
+ return "Object.f"
+}
+
+func PrintFer(fer Fer) {
+ fmt.Sprintln(fer.f())
+}
diff --git a/go/test/fixedbugs/bug414.dir/prog.go b/go/test/fixedbugs/bug414.dir/prog.go
new file mode 100644
index 0000000000000000000000000000000000000000..8945d6543d6d2ed7845ddf7c5cfb78824086a2d8
--- /dev/null
+++ b/go/test/fixedbugs/bug414.dir/prog.go
@@ -0,0 +1,18 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./p1"
+
+type MyObject struct {
+ p1.Fer
+}
+
+func main() {
+ var b p1.Fer = &p1.Object{}
+ p1.PrintFer(b)
+ var c p1.Fer = &MyObject{b}
+ p1.PrintFer(c)
+}
diff --git a/go/test/fixedbugs/bug415.dir/p.go b/go/test/fixedbugs/bug415.dir/p.go
new file mode 100644
index 0000000000000000000000000000000000000000..e86a697643b3f755989a5f4757e13a105fa187eb
--- /dev/null
+++ b/go/test/fixedbugs/bug415.dir/p.go
@@ -0,0 +1,14 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+type A struct {
+ s struct{int}
+}
+
+func (a *A) f() {
+ a.s = struct{int}{0}
+}
+
diff --git a/go/test/fixedbugs/bug415.dir/prog.go b/go/test/fixedbugs/bug415.dir/prog.go
new file mode 100644
index 0000000000000000000000000000000000000000..1ffde188b7858e0973a3bda3eb602570b4b0bc64
--- /dev/null
+++ b/go/test/fixedbugs/bug415.dir/prog.go
@@ -0,0 +1,9 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+import "./p"
+func main() {}
+var _ p.A
+
diff --git a/go/test/fixedbugs/bug424.dir/lib.go b/go/test/fixedbugs/bug424.dir/lib.go
new file mode 100644
index 0000000000000000000000000000000000000000..31df8c600f3a284da534c5d195b3a7a0f3c29d6b
--- /dev/null
+++ b/go/test/fixedbugs/bug424.dir/lib.go
@@ -0,0 +1,16 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package lib
+
+type I interface {
+ m() string
+}
+
+type T struct{}
+
+// m is not accessible from outside this package.
+func (t *T) m() string {
+ return "lib.T.m"
+}
diff --git a/go/test/fixedbugs/bug424.dir/main.go b/go/test/fixedbugs/bug424.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..28b41e68a737dfe9e3e43f0b2c99238c673ddc54
--- /dev/null
+++ b/go/test/fixedbugs/bug424.dir/main.go
@@ -0,0 +1,97 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Tests that method calls through an interface always
+// call the locally defined method localT.m independent
+// at which embedding level it is and in which order
+// embedding is done.
+
+package main
+
+import "./lib"
+import "reflect"
+import "fmt"
+
+type localI interface {
+ m() string
+}
+
+type localT struct{}
+
+func (t *localT) m() string {
+ return "main.localT.m"
+}
+
+type myT1 struct {
+ localT
+}
+
+type myT2 struct {
+ localT
+ lib.T
+}
+
+type myT3 struct {
+ lib.T
+ localT
+}
+
+func main() {
+ var i localI
+
+ i = new(localT)
+ if i.m() != "main.localT.m" {
+ println("BUG: localT:", i.m(), "called")
+ }
+
+ i = new(myT1)
+ if i.m() != "main.localT.m" {
+ println("BUG: myT1:", i.m(), "called")
+ }
+
+ i = new(myT2)
+ if i.m() != "main.localT.m" {
+ println("BUG: myT2:", i.m(), "called")
+ }
+
+ t3 := new(myT3)
+ if t3.m() != "main.localT.m" {
+ println("BUG: t3:", t3.m(), "called")
+ }
+
+ i = new(myT3)
+ if i.m() != "main.localT.m" {
+ t := reflect.TypeOf(i)
+ n := t.NumMethod()
+ for j := 0; j < n; j++ {
+ m := t.Method(j)
+ fmt.Printf("#%d: %s.%s %s\n", j, m.PkgPath, m.Name, m.Type)
+ }
+ println("BUG: myT3:", i.m(), "called")
+ }
+
+ var t4 struct {
+ localT
+ lib.T
+ }
+ if t4.m() != "main.localT.m" {
+ println("BUG: t4:", t4.m(), "called")
+ }
+ i = &t4
+ if i.m() != "main.localT.m" {
+ println("BUG: myT4:", i.m(), "called")
+ }
+
+ var t5 struct {
+ lib.T
+ localT
+ }
+ if t5.m() != "main.localT.m" {
+ println("BUG: t5:", t5.m(), "called")
+ }
+ i = &t5
+ if i.m() != "main.localT.m" {
+ println("BUG: myT5:", i.m(), "called")
+ }
+}
diff --git a/go/test/fixedbugs/bug437.dir/one.go b/go/test/fixedbugs/bug437.dir/one.go
new file mode 100644
index 0000000000000000000000000000000000000000..633573e51d1cb6ec3437f78cdd14637ca3e63814
--- /dev/null
+++ b/go/test/fixedbugs/bug437.dir/one.go
@@ -0,0 +1,18 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package one
+
+type I1 interface {
+ f()
+}
+
+type S1 struct {
+}
+
+func (s S1) f() {
+}
+
+func F1(i1 I1) {
+}
diff --git a/go/test/fixedbugs/bug437.dir/two.go b/go/test/fixedbugs/bug437.dir/two.go
new file mode 100644
index 0000000000000000000000000000000000000000..61da121d513270a8b6e7bcb9e10f939a3e315fb6
--- /dev/null
+++ b/go/test/fixedbugs/bug437.dir/two.go
@@ -0,0 +1,11 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package two
+
+import "./one"
+
+type S2 struct {
+ one.S1
+}
diff --git a/go/test/fixedbugs/bug437.dir/x.go b/go/test/fixedbugs/bug437.dir/x.go
new file mode 100644
index 0000000000000000000000000000000000000000..585b480c0a918f4cdba9475c0b2e418a25ecac8b
--- /dev/null
+++ b/go/test/fixedbugs/bug437.dir/x.go
@@ -0,0 +1,25 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test converting a type defined in a different package to an
+// interface defined in a third package, where the interface has a
+// hidden method. This used to cause a link error with gccgo.
+
+package main
+
+import (
+ "./one"
+ "./two"
+)
+
+func F(i1 one.I1) {
+ switch v := i1.(type) {
+ case two.S2:
+ one.F1(v)
+ }
+}
+
+func main() {
+ F(nil)
+}
diff --git a/go/test/fixedbugs/bug448.dir/pkg1.go b/go/test/fixedbugs/bug448.dir/pkg1.go
new file mode 100644
index 0000000000000000000000000000000000000000..291903ca459f3d5dc6ac3db0685938ad1ace0cfb
--- /dev/null
+++ b/go/test/fixedbugs/bug448.dir/pkg1.go
@@ -0,0 +1,11 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package pkg1
+
+var x = make(chan interface{})
+
+func Do() int {
+ return (<-x).(int)
+}
diff --git a/go/test/fixedbugs/bug448.dir/pkg2.go b/go/test/fixedbugs/bug448.dir/pkg2.go
new file mode 100644
index 0000000000000000000000000000000000000000..20d850915dde7ea16e93da6a323939bf7fd98f95
--- /dev/null
+++ b/go/test/fixedbugs/bug448.dir/pkg2.go
@@ -0,0 +1,14 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Issue 3843: inlining bug due to wrong receive operator precedence.
+
+package pkg2
+
+import "./pkg1"
+
+func F() {
+ pkg1.Do()
+}
+
diff --git a/go/test/fixedbugs/bug460.dir/a.go b/go/test/fixedbugs/bug460.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..51c6836be7e92914f27c58e97205540956c30fea
--- /dev/null
+++ b/go/test/fixedbugs/bug460.dir/a.go
@@ -0,0 +1,13 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type Foo struct {
+ int
+ int8
+ error
+ rune
+ byte
+}
diff --git a/go/test/fixedbugs/bug460.dir/b.go b/go/test/fixedbugs/bug460.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..5d388fc413f783de1aa93fe6c0aacab463b87e63
--- /dev/null
+++ b/go/test/fixedbugs/bug460.dir/b.go
@@ -0,0 +1,17 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+var x a.Foo
+
+func main() {
+ x.int = 20 // ERROR "unexported field|undefined"
+ x.int8 = 20 // ERROR "unexported field|undefined"
+ x.error = nil // ERROR "unexported field|undefined"
+ x.rune = 'a' // ERROR "unexported field|undefined"
+ x.byte = 20 // ERROR "unexported field|undefined"
+}
diff --git a/go/test/fixedbugs/bug465.dir/a.go b/go/test/fixedbugs/bug465.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..3e5d012e6a1097061c81f04ef6a12f54652c7c4f
--- /dev/null
+++ b/go/test/fixedbugs/bug465.dir/a.go
@@ -0,0 +1,76 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type T struct{ A, B int }
+
+type A []int
+
+type M map[int]int
+
+func F1() int {
+ if (T{1, 2}) == (T{3, 4}) {
+ return 1
+ }
+ return 0
+}
+
+func F2() int {
+ if (M{1: 2}) == nil {
+ return 1
+ }
+ return 0
+}
+
+func F3() int {
+ if nil == (A{}) {
+ return 1
+ }
+ return 0
+}
+
+func F4() int {
+ if a := (A{}); a == nil {
+ return 1
+ }
+ return 0
+}
+
+func F5() int {
+ for k, v := range (M{1: 2}) {
+ return v - k
+ }
+ return 0
+}
+
+func F6() int {
+ switch a := (T{1, 1}); a == (T{1, 2}) {
+ default:
+ return 1
+ }
+ return 0
+}
+
+func F7() int {
+ for m := (M{}); len(m) < (T{1, 2}).A; m[1] = (A{1})[0] {
+ return 1
+ }
+ return 0
+}
+
+func F8() int {
+ if a := (&T{1, 1}); a != nil {
+ return 1
+ }
+ return 0
+}
+
+func F9() int {
+ var a *T
+ if a = (&T{1, 1}); a != nil {
+ return 1
+ }
+ return 0
+}
diff --git a/go/test/fixedbugs/bug465.dir/b.go b/go/test/fixedbugs/bug465.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..db7f7315e6ab093f912b540791787a4612d9901f
--- /dev/null
+++ b/go/test/fixedbugs/bug465.dir/b.go
@@ -0,0 +1,17 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+func main() {
+ for _, f := range []func() int{
+ a.F1, a.F2, a.F3, a.F4,
+ a.F5, a.F6, a.F7, a.F8, a.F9} {
+ if f() > 1 {
+ panic("f() > 1")
+ }
+ }
+}
diff --git a/go/test/fixedbugs/bug466.dir/a.go b/go/test/fixedbugs/bug466.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..e27699c2ef51ff6ad40c00ff43c17a508bbd0b46
--- /dev/null
+++ b/go/test/fixedbugs/bug466.dir/a.go
@@ -0,0 +1,15 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+const N = 2+3i
+
+func Func() []complex128 {
+ return []complex128{1, complex(2, 3), complex(4, 5)}
+}
+
+func Mul(z complex128) complex128 {
+ return z * (3 + 4i)
+}
diff --git a/go/test/fixedbugs/bug466.dir/b.go b/go/test/fixedbugs/bug466.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..04e3626c7524d145c0eefe174db9481b00b46639
--- /dev/null
+++ b/go/test/fixedbugs/bug466.dir/b.go
@@ -0,0 +1,30 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+func main() {
+ s := a.Func()
+ if s[0] != 1 {
+ println(s[0])
+ panic("s[0] != 1")
+ }
+ if s[1] != 2+3i {
+ println(s[1])
+ panic("s[1] != 2+3i")
+ }
+ if s[2] != 4+5i {
+ println(s[2])
+ panic("s[2] != 4+5i")
+ }
+
+ x := 1 + 2i
+ y := a.Mul(x)
+ if y != (1+2i)*(3+4i) {
+ println(y)
+ panic("y != (1+2i)*(3+4i)")
+ }
+}
diff --git a/go/test/fixedbugs/bug467.dir/p1.go b/go/test/fixedbugs/bug467.dir/p1.go
new file mode 100644
index 0000000000000000000000000000000000000000..538b554f8e3970b1a043231e172470b27679725e
--- /dev/null
+++ b/go/test/fixedbugs/bug467.dir/p1.go
@@ -0,0 +1,5 @@
+package p1
+
+type SockaddrUnix int
+
+func (s SockaddrUnix) Error() string { return "blah" }
diff --git a/go/test/fixedbugs/bug467.dir/p2.go b/go/test/fixedbugs/bug467.dir/p2.go
new file mode 100644
index 0000000000000000000000000000000000000000..d80d3a30b185d927e9f1f22eaa5d01bb4f604d52
--- /dev/null
+++ b/go/test/fixedbugs/bug467.dir/p2.go
@@ -0,0 +1,5 @@
+package p2
+
+import "./p1"
+
+func SockUnix() error { var s *p1.SockaddrUnix; return s }
diff --git a/go/test/fixedbugs/bug467.dir/p3.go b/go/test/fixedbugs/bug467.dir/p3.go
new file mode 100644
index 0000000000000000000000000000000000000000..c795646472fc0a460cb535868f3fa690d80ba8ec
--- /dev/null
+++ b/go/test/fixedbugs/bug467.dir/p3.go
@@ -0,0 +1,7 @@
+package main
+
+import "./p2"
+
+func main() {
+ _ = p2.SockUnix()
+}
diff --git a/go/test/fixedbugs/bug468.dir/p1.go b/go/test/fixedbugs/bug468.dir/p1.go
new file mode 100644
index 0000000000000000000000000000000000000000..cdda735e965704d46b6ea7612539603600bbed77
--- /dev/null
+++ b/go/test/fixedbugs/bug468.dir/p1.go
@@ -0,0 +1,7 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p1
+
+type S struct { X, Y int }
diff --git a/go/test/fixedbugs/bug468.dir/p2.go b/go/test/fixedbugs/bug468.dir/p2.go
new file mode 100644
index 0000000000000000000000000000000000000000..dbb46931b825f2d64ca31e62b298946277cc6ae9
--- /dev/null
+++ b/go/test/fixedbugs/bug468.dir/p2.go
@@ -0,0 +1,25 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "reflect"
+
+ "./p1"
+)
+
+func main() {
+ var v1 = p1.S{1, 2}
+ var v2 = struct { X, Y int }{1, 2}
+ v1 = v2
+ t1 := reflect.TypeOf(v1)
+ t2 := reflect.TypeOf(v2)
+ if !t1.AssignableTo(t2) {
+ panic(0)
+ }
+ if !t2.AssignableTo(t1) {
+ panic(1)
+ }
+}
diff --git a/go/test/fixedbugs/bug472.dir/p1.go b/go/test/fixedbugs/bug472.dir/p1.go
new file mode 100644
index 0000000000000000000000000000000000000000..cda1aa7aa8c0f6377f636f4c3c62ceabb3b4857e
--- /dev/null
+++ b/go/test/fixedbugs/bug472.dir/p1.go
@@ -0,0 +1,17 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p1
+
+import "runtime"
+
+func E() func() int { return runtime.NumCPU }
+
+func F() func() { return runtime.Gosched }
+
+func G() func() string { return runtime.GOROOT }
+
+func H() func() { return runtime.GC }
+
+func I() func() string { return runtime.Version }
diff --git a/go/test/fixedbugs/bug472.dir/p2.go b/go/test/fixedbugs/bug472.dir/p2.go
new file mode 100644
index 0000000000000000000000000000000000000000..581ec400200fd1953566be9191c7f5f52b4e2994
--- /dev/null
+++ b/go/test/fixedbugs/bug472.dir/p2.go
@@ -0,0 +1,17 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p2
+
+import "runtime"
+
+func E() func() int { return runtime.NumCPU }
+
+func F() func() { return runtime.GC }
+
+func G() func() string { return runtime.GOROOT }
+
+func H() func() { return runtime.Gosched }
+
+func I() func() string { return runtime.Version }
diff --git a/go/test/fixedbugs/bug472.dir/z.go b/go/test/fixedbugs/bug472.dir/z.go
new file mode 100644
index 0000000000000000000000000000000000000000..eb791bf443a3b33babcbf21c090c809ddfc12982
--- /dev/null
+++ b/go/test/fixedbugs/bug472.dir/z.go
@@ -0,0 +1,13 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ _ "./p1"
+ _ "./p2"
+)
+
+func main() {
+}
diff --git a/go/test/fixedbugs/bug478.dir/a.go b/go/test/fixedbugs/bug478.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..b5a2dbcdb88a33e1e444d8aafbbcda8d801022c5
--- /dev/null
+++ b/go/test/fixedbugs/bug478.dir/a.go
@@ -0,0 +1,9 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p1
+
+type S1 struct{}
+
+func (s S1) f() {}
diff --git a/go/test/fixedbugs/bug478.dir/b.go b/go/test/fixedbugs/bug478.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..cfd1d273d8e6fc087812cda17a5e822148a6a7f6
--- /dev/null
+++ b/go/test/fixedbugs/bug478.dir/b.go
@@ -0,0 +1,13 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p2
+
+import "./a"
+
+type S2 struct {
+ p1.S1
+}
+
+func (s S2) f() {}
diff --git a/go/test/fixedbugs/bug479.dir/a.go b/go/test/fixedbugs/bug479.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..eddb4cf0781a17bc105baa5e25082c0a1b546d9e
--- /dev/null
+++ b/go/test/fixedbugs/bug479.dir/a.go
@@ -0,0 +1,15 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+import "unsafe"
+
+type S2 struct {}
+
+const C = unsafe.Sizeof(S2{})
+
+type S1 struct {
+ S2
+}
diff --git a/go/test/fixedbugs/bug479.dir/b.go b/go/test/fixedbugs/bug479.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..9f3f5e8f523d1af736ea290690bbfb6a731a12ef
--- /dev/null
+++ b/go/test/fixedbugs/bug479.dir/b.go
@@ -0,0 +1,16 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+type S3 struct {
+ p.S1
+}
+
+func main() {
+ var i interface{} = S3{}
+ _ = i
+}
diff --git a/go/test/fixedbugs/bug480.dir/a.go b/go/test/fixedbugs/bug480.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..26a8d1166976a45d3a76128fcc99cd91eefc53d3
--- /dev/null
+++ b/go/test/fixedbugs/bug480.dir/a.go
@@ -0,0 +1,17 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type S interface{
+ F() T
+}
+
+type T struct {
+ S
+}
+
+type U struct {
+ error
+}
diff --git a/go/test/fixedbugs/bug480.dir/b.go b/go/test/fixedbugs/bug480.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..5bd40f6205e32d261a4e53e6b098f788e14583ee
--- /dev/null
+++ b/go/test/fixedbugs/bug480.dir/b.go
@@ -0,0 +1,13 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+var t a.T
+
+func F() error {
+ return a.U{}
+}
diff --git a/go/test/fixedbugs/bug488.dir/a.go b/go/test/fixedbugs/bug488.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..fc494207a1739907bd05d69af9568fba7e3036c5
--- /dev/null
+++ b/go/test/fixedbugs/bug488.dir/a.go
@@ -0,0 +1,7 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+var p2 = Printf // ERROR "undefined"
diff --git a/go/test/fixedbugs/bug488.dir/b.go b/go/test/fixedbugs/bug488.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..f93328c8da4a04a4efaf6431358dc65a9b358ce5
--- /dev/null
+++ b/go/test/fixedbugs/bug488.dir/b.go
@@ -0,0 +1,9 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+import . "fmt"
+
+var p1 = Print
diff --git a/go/test/fixedbugs/bug492.dir/a.go b/go/test/fixedbugs/bug492.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..90917e55e839ba82754b5543d3c7ac43f5e2e23c
--- /dev/null
+++ b/go/test/fixedbugs/bug492.dir/a.go
@@ -0,0 +1,16 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type s struct {
+ s string
+}
+
+func F1(s s) {
+}
+
+func F2() s {
+ return s{""}
+}
diff --git a/go/test/fixedbugs/bug492.dir/b.go b/go/test/fixedbugs/bug492.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..5b8c4f2a533eb8d68f24e2c323567a21aca1b33a
--- /dev/null
+++ b/go/test/fixedbugs/bug492.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+func main() {
+ defer a.F1(a.F2())
+}
diff --git a/go/test/fixedbugs/bug504.dir/a.go b/go/test/fixedbugs/bug504.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..ac0be937ab2d8cb08e688e364d1ab5cc8672d96f
--- /dev/null
+++ b/go/test/fixedbugs/bug504.dir/a.go
@@ -0,0 +1,7 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type MyInt = int
diff --git a/go/test/fixedbugs/bug504.dir/b.go b/go/test/fixedbugs/bug504.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..e8f8da9af88a42efb6c7a39501edc52a8af61415
--- /dev/null
+++ b/go/test/fixedbugs/bug504.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func F() a.MyInt {
+ return 0
+}
diff --git a/go/test/fixedbugs/bug504.dir/c.go b/go/test/fixedbugs/bug504.dir/c.go
new file mode 100644
index 0000000000000000000000000000000000000000..5a6e889905986aad5ae22b891bf579210d96bb3a
--- /dev/null
+++ b/go/test/fixedbugs/bug504.dir/c.go
@@ -0,0 +1,9 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package c
+
+import "./b"
+
+var V = b.F()
diff --git a/go/test/fixedbugs/bug504.dir/main.go b/go/test/fixedbugs/bug504.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..bdbd95c7a3143dabb19a9761bbeca1e0df0acbdf
--- /dev/null
+++ b/go/test/fixedbugs/bug504.dir/main.go
@@ -0,0 +1,11 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./c"
+
+func main() {
+ println(c.V)
+}
diff --git a/go/test/fixedbugs/bug506.dir/a.go b/go/test/fixedbugs/bug506.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..8e8a2005810fa1fa2a52f98c585d3d60de186b55
--- /dev/null
+++ b/go/test/fixedbugs/bug506.dir/a.go
@@ -0,0 +1,16 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type internal struct {
+ f1 string
+ f2 float64
+}
+
+type S struct {
+ F struct {
+ I internal
+ }
+}
diff --git a/go/test/fixedbugs/bug506.dir/main.go b/go/test/fixedbugs/bug506.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..1b60e40d8d0a448852e5bcbc3542eed2b82f5b4b
--- /dev/null
+++ b/go/test/fixedbugs/bug506.dir/main.go
@@ -0,0 +1,20 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "fmt"
+
+ "./a"
+)
+
+var v = a.S{}
+
+func main() {
+ want := "{{ 0}}"
+ if got := fmt.Sprint(v.F); got != want {
+ panic(got)
+ }
+}
diff --git a/go/test/fixedbugs/bug507.dir/a.go b/go/test/fixedbugs/bug507.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..0929adcfb3168da785549f05ec3bd50ff9e195ae
--- /dev/null
+++ b/go/test/fixedbugs/bug507.dir/a.go
@@ -0,0 +1,13 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type I interface {
+ M()
+}
+
+type S struct {
+ I I
+}
diff --git a/go/test/fixedbugs/bug507.dir/b.go b/go/test/fixedbugs/bug507.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..bddce2dd8392d1fc61bb990c4d1f90216b3b87ef
--- /dev/null
+++ b/go/test/fixedbugs/bug507.dir/b.go
@@ -0,0 +1,9 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import . "./a"
+
+var V2 I
diff --git a/go/test/fixedbugs/bug507.dir/c.go b/go/test/fixedbugs/bug507.dir/c.go
new file mode 100644
index 0000000000000000000000000000000000000000..e67f0fd74e82593e75c3e4421da843adca9e42f1
--- /dev/null
+++ b/go/test/fixedbugs/bug507.dir/c.go
@@ -0,0 +1,9 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+var V1 = a.S{I: nil}
diff --git a/go/test/fixedbugs/bug510.dir/a.go b/go/test/fixedbugs/bug510.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..db1cfef366d5500182ed07674a31347c0956b34a
--- /dev/null
+++ b/go/test/fixedbugs/bug510.dir/a.go
@@ -0,0 +1,13 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+import "reflect"
+
+type A = map[int] bool
+
+func F() interface{} {
+ return reflect.New(reflect.TypeOf((*A)(nil))).Elem().Interface()
+}
diff --git a/go/test/fixedbugs/bug510.dir/b.go b/go/test/fixedbugs/bug510.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..56b0201858cac39d0776c5552c08882aebaba2cb
--- /dev/null
+++ b/go/test/fixedbugs/bug510.dir/b.go
@@ -0,0 +1,14 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+func main() {
+ _, ok := a.F().(*map[int]bool)
+ if !ok {
+ panic("bad type")
+ }
+}
diff --git a/go/test/fixedbugs/bug511.dir/a.go b/go/test/fixedbugs/bug511.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..33931a07a87bf032fb0899fa05e7d2f363a7a8b2
--- /dev/null
+++ b/go/test/fixedbugs/bug511.dir/a.go
@@ -0,0 +1,11 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type S struct{}
+
+type A = S
+
+func (A) M() {}
diff --git a/go/test/fixedbugs/bug511.dir/b.go b/go/test/fixedbugs/bug511.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..f8877d6afd04f6445f1076bdb19b54802c3e440b
--- /dev/null
+++ b/go/test/fixedbugs/bug511.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func F() {
+ a.S{}.M()
+}
diff --git a/go/test/fixedbugs/gcc67968.dir/a.go b/go/test/fixedbugs/gcc67968.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..9f51a7a8bc5913c1fe8c0543a4199d095220c11d
--- /dev/null
+++ b/go/test/fixedbugs/gcc67968.dir/a.go
@@ -0,0 +1,12 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type T int
+
+func (a *T) Foo() [1]string {
+ var r [1]string
+ return r
+}
diff --git a/go/test/fixedbugs/gcc67968.dir/b.go b/go/test/fixedbugs/gcc67968.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..41b62d2088070279f643409cde8e4f02b113d3e7
--- /dev/null
+++ b/go/test/fixedbugs/gcc67968.dir/b.go
@@ -0,0 +1,12 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func F() (interface{}) {
+ var v *a.T
+ return v.Foo()
+}
diff --git a/go/test/fixedbugs/issue10066.dir/a.go b/go/test/fixedbugs/issue10066.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..8bb3b303ea603f4f82b9bf763fb0d0d04d6d9698
--- /dev/null
+++ b/go/test/fixedbugs/issue10066.dir/a.go
@@ -0,0 +1,11 @@
+package a
+
+import "log"
+
+func Do() {
+ Do2()
+}
+
+func Do2() {
+ println(log.Ldate | log.Ltime | log.Lshortfile)
+}
diff --git a/go/test/fixedbugs/issue10066.dir/b.go b/go/test/fixedbugs/issue10066.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..46d2f55fed63e098ab46e2fe52a1ad612f56e37e
--- /dev/null
+++ b/go/test/fixedbugs/issue10066.dir/b.go
@@ -0,0 +1,7 @@
+package b
+
+import "./a"
+
+func test() {
+ a.Do()
+}
diff --git a/go/test/fixedbugs/issue10219.dir/a.go b/go/test/fixedbugs/issue10219.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..c61d02b66a97450f4e678354dd093de6ab50b445
--- /dev/null
+++ b/go/test/fixedbugs/issue10219.dir/a.go
@@ -0,0 +1,24 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type m struct {
+ S string
+}
+
+var g = struct {
+ m
+ P string
+}{
+ m{"a"},
+ "",
+}
+
+type S struct{}
+
+func (s *S) M(p string) {
+ r := g
+ r.P = p
+}
diff --git a/go/test/fixedbugs/issue10219.dir/b.go b/go/test/fixedbugs/issue10219.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..09d8911ff4aa77b4a59e0ad9feaf36c11a8843f9
--- /dev/null
+++ b/go/test/fixedbugs/issue10219.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func F() *a.S {
+ return &a.S{}
+}
diff --git a/go/test/fixedbugs/issue10219.dir/c.go b/go/test/fixedbugs/issue10219.dir/c.go
new file mode 100644
index 0000000000000000000000000000000000000000..d331495df204d7adf9182c43d1fdd427a6c20844
--- /dev/null
+++ b/go/test/fixedbugs/issue10219.dir/c.go
@@ -0,0 +1,12 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package c
+
+import "./b"
+
+func F() {
+ s := b.F()
+ s.M("c")
+}
diff --git a/go/test/fixedbugs/issue10700.dir/other.go b/go/test/fixedbugs/issue10700.dir/other.go
new file mode 100644
index 0000000000000000000000000000000000000000..12908b92053a37249d14a661d92f99f303d6c2a6
--- /dev/null
+++ b/go/test/fixedbugs/issue10700.dir/other.go
@@ -0,0 +1,10 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package other
+
+type Exported interface {
+ Do()
+ secret()
+}
diff --git a/go/test/fixedbugs/issue10700.dir/test.go b/go/test/fixedbugs/issue10700.dir/test.go
new file mode 100644
index 0000000000000000000000000000000000000000..2dfc24af077cce048195d0dcb2570b294a76f27d
--- /dev/null
+++ b/go/test/fixedbugs/issue10700.dir/test.go
@@ -0,0 +1,49 @@
+// errorcheck -0 -m -l
+
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./other"
+
+type Imported interface {
+ Do()
+}
+
+type HasAMethod struct {
+ x int
+}
+
+func (me *HasAMethod) Do() {
+ println(me.x)
+}
+
+func InMyCode(x *Imported, y *HasAMethod, z *other.Exported) {
+ x.Do() // ERROR "x\.Do undefined \(type \*Imported is pointer to interface, not interface\)|type that is pointer to interface"
+ x.do() // ERROR "x\.do undefined \(type \*Imported is pointer to interface, not interface\)|type that is pointer to interface"
+ (*x).Do()
+ x.Dont() // ERROR "x\.Dont undefined \(type \*Imported is pointer to interface, not interface\)|type that is pointer to interface"
+ (*x).Dont() // ERROR "\(\*x\)\.Dont undefined \(type Imported has no field or method Dont\)|reference to undefined field or method"
+
+ y.Do()
+ y.do() // ERROR "y\.do undefined \(type \*HasAMethod has no field or method do, but does have Do\)|reference to undefined field or method"
+ (*y).Do()
+ (*y).do() // ERROR "\(\*y\)\.do undefined \(type HasAMethod has no field or method do, but does have Do\)|reference to undefined field or method"
+ y.Dont() // ERROR "y\.Dont undefined \(type \*HasAMethod has no field or method Dont\)|reference to undefined field or method"
+ (*y).Dont() // ERROR "\(\*y\)\.Dont undefined \(type HasAMethod has no field or method Dont\)|reference to undefined field or method"
+
+ z.Do() // ERROR "z\.Do undefined \(type \*other\.Exported is pointer to interface, not interface\)|type that is pointer to interface"
+ z.do() // ERROR "z\.do undefined \(type \*other\.Exported is pointer to interface, not interface\)|type that is pointer to interface"
+ (*z).Do()
+ (*z).do() // ERROR "\(\*z\)\.do undefined \(type other.Exported has no field or method do, but does have Do\)|reference to undefined field or method"
+ z.Dont() // ERROR "z\.Dont undefined \(type \*other\.Exported is pointer to interface, not interface\)|type that is pointer to interface"
+ (*z).Dont() // ERROR "\(\*z\)\.Dont undefined \(type other\.Exported has no field or method Dont\)|reference to undefined field or method"
+ z.secret() // ERROR "z\.secret undefined \(type \*other\.Exported is pointer to interface, not interface\)|type that is pointer to interface"
+ (*z).secret() // ERROR "\(\*z\)\.secret undefined \(cannot refer to unexported field or method secret\)|reference to unexported field or method"
+
+}
+
+func main() {
+}
diff --git a/go/test/fixedbugs/issue11053.dir/p.go b/go/test/fixedbugs/issue11053.dir/p.go
new file mode 100644
index 0000000000000000000000000000000000000000..81b412aef13a9f459f288dcea92b2f165a2b6ddd
--- /dev/null
+++ b/go/test/fixedbugs/issue11053.dir/p.go
@@ -0,0 +1,9 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+func Int32(i int32) *int32 {
+ return &i
+}
diff --git a/go/test/fixedbugs/issue11053.dir/p_test.go b/go/test/fixedbugs/issue11053.dir/p_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..412352d7c5e1f36026ef84600a8a8763653d3cbb
--- /dev/null
+++ b/go/test/fixedbugs/issue11053.dir/p_test.go
@@ -0,0 +1,51 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./p"
+ "fmt"
+)
+
+type I interface {
+ Add(out *P)
+}
+
+type P struct {
+ V *int32
+}
+
+type T struct{}
+
+var x int32 = 42
+
+func Int32x(i int32) *int32 {
+ return &i
+}
+
+func (T) Add(out *P) {
+ out.V = p.Int32(x) // inlined, p.i.2 moved to heap
+}
+
+var PP P
+var out *P = &PP
+
+func F(s I) interface{} {
+ s.Add(out) // not inlined.
+ return out
+}
+
+var s T
+
+func main() {
+ println("Starting")
+ fmt.Sprint(new(int32))
+ resp := F(s).(*P)
+ println("Before, *resp.V=", *resp.V) // Trashes *resp.V in process of printing.
+ println("After, *resp.V=", *resp.V)
+ if got, want := *resp.V, int32(42); got != want {
+ fmt.Printf("FAIL, got %v, want %v", got, want)
+ }
+}
diff --git a/go/test/fixedbugs/issue11656.dir/asm.go b/go/test/fixedbugs/issue11656.dir/asm.go
new file mode 100644
index 0000000000000000000000000000000000000000..c64302bd505e4562cc4529d9f3ca13b927a8e6e4
--- /dev/null
+++ b/go/test/fixedbugs/issue11656.dir/asm.go
@@ -0,0 +1,9 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build ppc64 || ppc64le
+
+package main
+
+func syncIcache(p uintptr)
diff --git a/go/test/fixedbugs/issue11656.dir/asm_generic.go b/go/test/fixedbugs/issue11656.dir/asm_generic.go
new file mode 100644
index 0000000000000000000000000000000000000000..a8b8f6a5e4f2af436f2bbd65b4b64b94f7bfa9bc
--- /dev/null
+++ b/go/test/fixedbugs/issue11656.dir/asm_generic.go
@@ -0,0 +1,10 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !ppc64 && !ppc64le
+
+package main
+
+func syncIcache(p uintptr) {
+}
diff --git a/go/test/fixedbugs/issue11656.dir/asm_ppc64.s b/go/test/fixedbugs/issue11656.dir/asm_ppc64.s
new file mode 100644
index 0000000000000000000000000000000000000000..125a197ed8e1f74f18e181546555895e85b5a8c0
--- /dev/null
+++ b/go/test/fixedbugs/issue11656.dir/asm_ppc64.s
@@ -0,0 +1,13 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// func syncIcache(p uintptr)
+TEXT main·syncIcache(SB), NOSPLIT|NOFRAME, $0-0
+ SYNC
+ MOVD (R3), R3
+ ICBI (R3)
+ ISYNC
+ RET
diff --git a/go/test/fixedbugs/issue11656.dir/asm_ppc64le.s b/go/test/fixedbugs/issue11656.dir/asm_ppc64le.s
new file mode 100644
index 0000000000000000000000000000000000000000..125a197ed8e1f74f18e181546555895e85b5a8c0
--- /dev/null
+++ b/go/test/fixedbugs/issue11656.dir/asm_ppc64le.s
@@ -0,0 +1,13 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// func syncIcache(p uintptr)
+TEXT main·syncIcache(SB), NOSPLIT|NOFRAME, $0-0
+ SYNC
+ MOVD (R3), R3
+ ICBI (R3)
+ ISYNC
+ RET
diff --git a/go/test/fixedbugs/issue11656.dir/issue11656.go b/go/test/fixedbugs/issue11656.dir/issue11656.go
new file mode 100644
index 0000000000000000000000000000000000000000..a5a52df698ad9ca1d5db3f1fb538a6e44feb9353
--- /dev/null
+++ b/go/test/fixedbugs/issue11656.dir/issue11656.go
@@ -0,0 +1,75 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "encoding/binary"
+ "runtime"
+ "runtime/debug"
+ "unsafe"
+)
+
+func main() {
+ debug.SetPanicOnFault(true)
+ defer func() {
+ if err := recover(); err == nil {
+ panic("not panicking")
+ }
+ pc, _, _, _ := runtime.Caller(10)
+ f := runtime.FuncForPC(pc)
+ if f == nil || f.Name() != "main.f" {
+ if f == nil {
+ println("no func for ", unsafe.Pointer(pc))
+ } else {
+ println("found func:", f.Name())
+ }
+ panic("cannot find main.f on stack")
+ }
+ }()
+ f(20)
+}
+
+func f(n int) {
+ if n > 0 {
+ f(n - 1)
+ }
+ var f struct {
+ x uintptr
+ }
+
+ // We want to force a seg fault, to get a crash at a PC value != 0.
+ // Not all systems make the data section non-executable.
+ ill := make([]byte, 64)
+ switch runtime.GOARCH {
+ case "386", "amd64":
+ ill = append(ill[:0], 0x89, 0x04, 0x25, 0x00, 0x00, 0x00, 0x00) // MOVL AX, 0
+ case "arm":
+ binary.LittleEndian.PutUint32(ill[0:4], 0xe3a00000) // MOVW $0, R0
+ binary.LittleEndian.PutUint32(ill[4:8], 0xe5800000) // MOVW R0, (R0)
+ case "arm64":
+ binary.LittleEndian.PutUint32(ill, 0xf90003ff) // MOVD ZR, (ZR)
+ case "ppc64":
+ binary.BigEndian.PutUint32(ill, 0xf8000000) // MOVD R0, (R0)
+ case "ppc64le":
+ binary.LittleEndian.PutUint32(ill, 0xf8000000) // MOVD R0, (R0)
+ case "mips", "mips64":
+ binary.BigEndian.PutUint32(ill, 0xfc000000) // MOVV R0, (R0)
+ case "mipsle", "mips64le":
+ binary.LittleEndian.PutUint32(ill, 0xfc000000) // MOVV R0, (R0)
+ case "s390x":
+ ill = append(ill[:0], 0xa7, 0x09, 0x00, 0x00) // MOVD $0, R0
+ ill = append(ill, 0xe3, 0x00, 0x00, 0x00, 0x00, 0x24) // MOVD R0, (R0)
+ case "riscv64":
+ binary.LittleEndian.PutUint32(ill, 0x00003023) // MOV X0, (X0)
+ default:
+ // Just leave it as 0 and hope for the best.
+ }
+
+ f.x = uintptr(unsafe.Pointer(&ill[0]))
+ p := &f
+ fn := *(*func())(unsafe.Pointer(&p))
+ syncIcache(f.x)
+ fn()
+}
diff --git a/go/test/fixedbugs/issue12677.dir/p.go b/go/test/fixedbugs/issue12677.dir/p.go
new file mode 100644
index 0000000000000000000000000000000000000000..e395071f8d545712eaa2b4d800abb5558c72d40a
--- /dev/null
+++ b/go/test/fixedbugs/issue12677.dir/p.go
@@ -0,0 +1,8 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+func Baz(f int) float64 {
+ return 1 / float64(int(1)<<(uint(f)))
+}
diff --git a/go/test/fixedbugs/issue12677.dir/q.go b/go/test/fixedbugs/issue12677.dir/q.go
new file mode 100644
index 0000000000000000000000000000000000000000..fd39c8a9ca6bcef0f1453dacbbec979b142e89c2
--- /dev/null
+++ b/go/test/fixedbugs/issue12677.dir/q.go
@@ -0,0 +1,7 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package q
+import "./p"
+func f() { println(p.Baz(2)) }
diff --git a/go/test/fixedbugs/issue13777.dir/burnin.go b/go/test/fixedbugs/issue13777.dir/burnin.go
new file mode 100644
index 0000000000000000000000000000000000000000..512563975ed64fa6ac60d95c00bc40f37a5bb0f1
--- /dev/null
+++ b/go/test/fixedbugs/issue13777.dir/burnin.go
@@ -0,0 +1,19 @@
+package burnin
+
+type sendCmdFunc func(string)
+
+func sendCommand(c string) {}
+
+func NewSomething() {
+ // This works...
+ // var sendCmd sendCmdFunc
+ // sendCmd = sendCommand
+
+ // So does this...
+ //sendCmd := sendCmdFunc(sendCommand)
+
+ // This fails...
+ sendCmd := sendCommand
+
+ _ = sendCmd
+}
diff --git a/go/test/fixedbugs/issue13777.dir/main.go b/go/test/fixedbugs/issue13777.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..2512b93a81a0395093c685bd63d30a4914fe1487
--- /dev/null
+++ b/go/test/fixedbugs/issue13777.dir/main.go
@@ -0,0 +1,11 @@
+// build
+
+package main
+
+import (
+ x "./burnin"
+)
+
+func main() {
+ x.NewSomething()
+}
diff --git a/go/test/fixedbugs/issue14164.dir/a.go b/go/test/fixedbugs/issue14164.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..bf03051619817a7f5f421d99d467a9eea6f95b64
--- /dev/null
+++ b/go/test/fixedbugs/issue14164.dir/a.go
@@ -0,0 +1,47 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+// F is an exported function, small enough to be inlined.
+// It defines a local interface with an unexported method
+// f, which will appear with a package-qualified method
+// name in the export data.
+func F(x interface{}) bool {
+ _, ok := x.(interface {
+ f()
+ })
+ return ok
+}
+
+// Like F but with the unexported interface method f
+// defined via an embedded interface t. The compiler
+// always flattens embedded interfaces so there should
+// be no difference between F and G. Alas, currently
+// G is not inlineable (at least via export data), so
+// the issue is moot, here.
+func G(x interface{}) bool {
+ type t0 interface {
+ f()
+ }
+ _, ok := x.(interface {
+ t0
+ })
+ return ok
+}
+
+// Like G but now the embedded interface is declared
+// at package level. This function is inlineable via
+// export data. The export data representation is like
+// for F.
+func H(x interface{}) bool {
+ _, ok := x.(interface {
+ t1
+ })
+ return ok
+}
+
+type t1 interface {
+ f()
+}
diff --git a/go/test/fixedbugs/issue14164.dir/main.go b/go/test/fixedbugs/issue14164.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..bcc6a63c2071588a0bf6da9fd2c868e0877f7a62
--- /dev/null
+++ b/go/test/fixedbugs/issue14164.dir/main.go
@@ -0,0 +1,12 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+// Verify that we can import package "a" containing an inlineable
+// function F that declares a local interface with a non-exported
+// method f.
+import _ "./a"
+
+func main() {}
diff --git a/go/test/fixedbugs/issue14331.dir/a.go b/go/test/fixedbugs/issue14331.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..f1e57ef52785658234739ffeaf04053beb8607a4
--- /dev/null
+++ b/go/test/fixedbugs/issue14331.dir/a.go
@@ -0,0 +1,14 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+var S struct {
+ Str string `tag`
+}
+
+func F() string {
+ v := S
+ return v.Str
+}
diff --git a/go/test/fixedbugs/issue14331.dir/b.go b/go/test/fixedbugs/issue14331.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..a2280a362979639bdbeacd2409143433c8c05da6
--- /dev/null
+++ b/go/test/fixedbugs/issue14331.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func G() string {
+ return a.F()
+}
diff --git a/go/test/fixedbugs/issue15071.dir/exp.go b/go/test/fixedbugs/issue15071.dir/exp.go
new file mode 100644
index 0000000000000000000000000000000000000000..e6041e602da3262c288ef150909a041a57281dd3
--- /dev/null
+++ b/go/test/fixedbugs/issue15071.dir/exp.go
@@ -0,0 +1,24 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package exp
+
+func Exported(x int) int {
+ return inlined(x)
+}
+
+func inlined(x int) int {
+ y := 0
+ switch {
+ case x > 0:
+ y += 5
+ return 0 + y
+ case x < 1:
+ y += 6
+ fallthrough
+ default:
+ y += 7
+ return 2 + y
+ }
+}
diff --git a/go/test/fixedbugs/issue15071.dir/main.go b/go/test/fixedbugs/issue15071.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..96790dae83ad17e21233045e3e9f77ec056fdbc1
--- /dev/null
+++ b/go/test/fixedbugs/issue15071.dir/main.go
@@ -0,0 +1,14 @@
+// run
+
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "os"
+import "./exp"
+
+func main() {
+ _ = exp.Exported(len(os.Args))
+}
diff --git a/go/test/fixedbugs/issue15470.dir/a.go b/go/test/fixedbugs/issue15470.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..1fcf3ea6e010ca91edcf5c290f4e260753e277f4
--- /dev/null
+++ b/go/test/fixedbugs/issue15470.dir/a.go
@@ -0,0 +1,24 @@
+package a
+
+import "io"
+
+type T interface {
+ M0(_ int)
+ M1(x, _ int) // _ (blank) caused crash
+ M2() (x, _ int)
+}
+
+type S struct{}
+
+func (S) M0(_ int) {}
+func (S) M1(x, _ int) {}
+func (S) M2() (x, _ int) { return }
+func (_ S) M3() {}
+
+// Snippet from x/tools/godoc/analysis/analysis.go.
+// Offending code from #5470.
+type Link interface {
+ Start() int
+ End() int
+ Write(w io.Writer, _ int, start bool) // _ (blank) caused crash
+}
diff --git a/go/test/fixedbugs/issue15470.dir/b.go b/go/test/fixedbugs/issue15470.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..863ee9f522196ab4075f074f2faa8bf64ff2462a
--- /dev/null
+++ b/go/test/fixedbugs/issue15470.dir/b.go
@@ -0,0 +1,3 @@
+package b
+
+import _ "./a" // must not fail
diff --git a/go/test/fixedbugs/issue15514.dir/a.go b/go/test/fixedbugs/issue15514.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..663303b863fe8a579ba5e51d86d1acbad99f664e
--- /dev/null
+++ b/go/test/fixedbugs/issue15514.dir/a.go
@@ -0,0 +1,7 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type A struct{ _ int32 }
diff --git a/go/test/fixedbugs/issue15514.dir/b.go b/go/test/fixedbugs/issue15514.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..f0750d3a443178addbe68e3085eebf25f2566dce
--- /dev/null
+++ b/go/test/fixedbugs/issue15514.dir/b.go
@@ -0,0 +1,7 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+func B() (_ struct{ _ int32 }) { return }
diff --git a/go/test/fixedbugs/issue15514.dir/c.go b/go/test/fixedbugs/issue15514.dir/c.go
new file mode 100644
index 0000000000000000000000000000000000000000..dc2ef5bed526db568bc7b151768c1f9f3f2ffbfe
--- /dev/null
+++ b/go/test/fixedbugs/issue15514.dir/c.go
@@ -0,0 +1,10 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package c
+
+import "./a"
+import "./b"
+
+var _ a.A = b.B() // ERROR "cannot use b\.B|incompatible type"
diff --git a/go/test/fixedbugs/issue15548.dir/a.go b/go/test/fixedbugs/issue15548.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..3c593fc0f6a4c8da4fa457503fa14f3691f8b662
--- /dev/null
+++ b/go/test/fixedbugs/issue15548.dir/a.go
@@ -0,0 +1,17 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type I0 interface {
+ I1
+}
+
+type T struct {
+ I1
+}
+
+type I1 interface {
+ M(*T) // removing * makes crash go away
+}
diff --git a/go/test/fixedbugs/issue15548.dir/b.go b/go/test/fixedbugs/issue15548.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..b46f5adfddbd07848ecade50b14f45e36130c491
--- /dev/null
+++ b/go/test/fixedbugs/issue15548.dir/b.go
@@ -0,0 +1,9 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+var X a.T
diff --git a/go/test/fixedbugs/issue15548.dir/c.go b/go/test/fixedbugs/issue15548.dir/c.go
new file mode 100644
index 0000000000000000000000000000000000000000..6d3f3be53ec2a465c95096d0692c1df7ccf5724b
--- /dev/null
+++ b/go/test/fixedbugs/issue15548.dir/c.go
@@ -0,0 +1,10 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package c
+
+import (
+ _ "./b"
+ _ "./a"
+)
diff --git a/go/test/fixedbugs/issue15572.dir/a.go b/go/test/fixedbugs/issue15572.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..1356601430471444af540e3220ddd90f7365355a
--- /dev/null
+++ b/go/test/fixedbugs/issue15572.dir/a.go
@@ -0,0 +1,40 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type T struct {
+}
+
+func F() []T {
+ return []T{T{}}
+}
+
+func Fi() []T {
+ return []T{{}} // element with implicit composite literal type
+}
+
+func Fp() []*T {
+ return []*T{&T{}}
+}
+
+func Fip() []*T {
+ return []*T{{}} // element with implicit composite literal type
+}
+
+func Gp() map[int]*T {
+ return map[int]*T{0: &T{}}
+}
+
+func Gip() map[int]*T {
+ return map[int]*T{0: {}} // element with implicit composite literal type
+}
+
+func Hp() map[*T]int {
+ return map[*T]int{&T{}: 0}
+}
+
+func Hip() map[*T]int {
+ return map[*T]int{{}: 0} // key with implicit composite literal type
+}
diff --git a/go/test/fixedbugs/issue15572.dir/b.go b/go/test/fixedbugs/issue15572.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..355accc88057bd3719659339be6a281d45cd620b
--- /dev/null
+++ b/go/test/fixedbugs/issue15572.dir/b.go
@@ -0,0 +1,27 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func F() {
+ a.F()
+ a.Fi()
+}
+
+func Fp() {
+ a.Fp()
+ a.Fip()
+}
+
+func Gp() {
+ a.Gp()
+ a.Gip()
+}
+
+func Hp() {
+ a.Hp()
+ a.Hip()
+}
diff --git a/go/test/fixedbugs/issue15609.dir/call.go b/go/test/fixedbugs/issue15609.dir/call.go
new file mode 100644
index 0000000000000000000000000000000000000000..48f90fd607f9e7331f9478fe196e6eb27d61dda8
--- /dev/null
+++ b/go/test/fixedbugs/issue15609.dir/call.go
@@ -0,0 +1,7 @@
+//go:build !amd64 && !386
+
+package main
+
+func jump() {
+ target()
+}
diff --git a/go/test/fixedbugs/issue15609.dir/call_386.s b/go/test/fixedbugs/issue15609.dir/call_386.s
new file mode 100644
index 0000000000000000000000000000000000000000..751084c485ba99aa41d43e69bfa7895fe33dcaec
--- /dev/null
+++ b/go/test/fixedbugs/issue15609.dir/call_386.s
@@ -0,0 +1,8 @@
+#include "textflag.h"
+
+DATA ·pointer(SB)/4, $·target(SB)
+GLOBL ·pointer(SB),RODATA,$4
+
+TEXT ·jump(SB),NOSPLIT,$4
+ CALL *·pointer(SB)
+ RET
diff --git a/go/test/fixedbugs/issue15609.dir/call_amd64.s b/go/test/fixedbugs/issue15609.dir/call_amd64.s
new file mode 100644
index 0000000000000000000000000000000000000000..09fbe5dfc4abda7b480fcfd801ce8b105c9ce8cd
--- /dev/null
+++ b/go/test/fixedbugs/issue15609.dir/call_amd64.s
@@ -0,0 +1,8 @@
+#include "textflag.h"
+
+DATA ·pointer(SB)/8, $·target(SB)
+GLOBL ·pointer(SB),RODATA,$8
+
+TEXT ·jump(SB),NOSPLIT,$8
+ CALL *·pointer(SB)
+ RET
diff --git a/go/test/fixedbugs/issue15609.dir/call_decl.go b/go/test/fixedbugs/issue15609.dir/call_decl.go
new file mode 100644
index 0000000000000000000000000000000000000000..cdca44a6542f80cb5fc591c63e85f5da704941a4
--- /dev/null
+++ b/go/test/fixedbugs/issue15609.dir/call_decl.go
@@ -0,0 +1,5 @@
+//go:build amd64 || 386
+
+package main
+
+func jump()
diff --git a/go/test/fixedbugs/issue15609.dir/main.go b/go/test/fixedbugs/issue15609.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..4855e31e5ed8f2d4255a5802c4b934e847aca15a
--- /dev/null
+++ b/go/test/fixedbugs/issue15609.dir/main.go
@@ -0,0 +1,14 @@
+package main
+
+var called bool
+
+func target() {
+ called = true
+}
+
+func main() {
+ jump()
+ if !called {
+ panic("target not called")
+ }
+}
diff --git a/go/test/fixedbugs/issue15646.dir/a.go b/go/test/fixedbugs/issue15646.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..842f19685fd282c91976dc84875dc726a58d4fc0
--- /dev/null
+++ b/go/test/fixedbugs/issue15646.dir/a.go
@@ -0,0 +1,23 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type T struct{}
+
+func (T) m() string {
+ return "m"
+}
+
+func (*T) mp() string {
+ return "mp"
+}
+
+func F() func(T) string {
+ return T.m // method expression
+}
+
+func Fp() func(*T) string {
+ return (*T).mp // method expression
+}
diff --git a/go/test/fixedbugs/issue15646.dir/b.go b/go/test/fixedbugs/issue15646.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..3d011ba30195b8ea7c0d6546108e7465946f3ee7
--- /dev/null
+++ b/go/test/fixedbugs/issue15646.dir/b.go
@@ -0,0 +1,16 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a" // import must succeed
+
+func main() {
+ if a.F()(a.T{}) != "m" {
+ panic(0)
+ }
+ if a.Fp()(nil) != "mp" {
+ panic(1)
+ }
+}
diff --git a/go/test/fixedbugs/issue15838.dir/a.go b/go/test/fixedbugs/issue15838.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..15b7f1dcfa8230a9e30e8b0f5996c94fcec31750
--- /dev/null
+++ b/go/test/fixedbugs/issue15838.dir/a.go
@@ -0,0 +1,61 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func F1() {
+L:
+ goto L
+}
+
+func F2() {
+L:
+ for {
+ break L
+ }
+}
+
+func F3() {
+L:
+ for {
+ continue L
+ }
+}
+
+func F4() {
+ switch {
+ case true:
+ fallthrough
+ default:
+ }
+}
+
+type T struct{}
+
+func (T) M1() {
+L:
+ goto L
+}
+
+func (T) M2() {
+L:
+ for {
+ break L
+ }
+}
+
+func (T) M3() {
+L:
+ for {
+ continue L
+ }
+}
+
+func (T) M4() {
+ switch {
+ case true:
+ fallthrough
+ default:
+ }
+}
diff --git a/go/test/fixedbugs/issue15838.dir/b.go b/go/test/fixedbugs/issue15838.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..9fd6efc33c9b8958576cdaa08961f55f3df3a087
--- /dev/null
+++ b/go/test/fixedbugs/issue15838.dir/b.go
@@ -0,0 +1,9 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+type T struct{ a.T }
diff --git a/go/test/fixedbugs/issue15920.dir/a.go b/go/test/fixedbugs/issue15920.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..15f92355f730ff6035950c9db32dac0a9d561310
--- /dev/null
+++ b/go/test/fixedbugs/issue15920.dir/a.go
@@ -0,0 +1,9 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type Error error
+
+func F() Error { return nil }
diff --git a/go/test/fixedbugs/issue15920.dir/b.go b/go/test/fixedbugs/issue15920.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..0a36c5c6ab80415c038d8e5cf25c03ef687d6da6
--- /dev/null
+++ b/go/test/fixedbugs/issue15920.dir/b.go
@@ -0,0 +1,7 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import _ "./a"
diff --git a/go/test/fixedbugs/issue16133.dir/a1.go b/go/test/fixedbugs/issue16133.dir/a1.go
new file mode 100644
index 0000000000000000000000000000000000000000..497cccf3633f957192c07ae58e63792754bc31d9
--- /dev/null
+++ b/go/test/fixedbugs/issue16133.dir/a1.go
@@ -0,0 +1,7 @@
+package a
+
+type X string
+
+func NewX() X {
+ return ""
+}
diff --git a/go/test/fixedbugs/issue16133.dir/a2.go b/go/test/fixedbugs/issue16133.dir/a2.go
new file mode 100644
index 0000000000000000000000000000000000000000..497cccf3633f957192c07ae58e63792754bc31d9
--- /dev/null
+++ b/go/test/fixedbugs/issue16133.dir/a2.go
@@ -0,0 +1,7 @@
+package a
+
+type X string
+
+func NewX() X {
+ return ""
+}
diff --git a/go/test/fixedbugs/issue16133.dir/b.go b/go/test/fixedbugs/issue16133.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..be1bebf889e22ca6f78f7e068f37e9c19c5eb621
--- /dev/null
+++ b/go/test/fixedbugs/issue16133.dir/b.go
@@ -0,0 +1,7 @@
+package b
+
+import "./a2"
+
+type T struct {
+ X a.X
+}
diff --git a/go/test/fixedbugs/issue16133.dir/c.go b/go/test/fixedbugs/issue16133.dir/c.go
new file mode 100644
index 0000000000000000000000000000000000000000..b25fe5a9ddb52058e70da3e07217d98ec4bf85b0
--- /dev/null
+++ b/go/test/fixedbugs/issue16133.dir/c.go
@@ -0,0 +1,10 @@
+package p
+
+import (
+ "./a1"
+ "./b"
+)
+
+var _ = b.T{
+ X: a.NewX(), // ERROR `cannot use "a1"\.NewX\(\)`
+}
diff --git a/go/test/fixedbugs/issue16317.dir/a.go b/go/test/fixedbugs/issue16317.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..3a1b7e021d395d74791f00f066b262eff80fb42a
--- /dev/null
+++ b/go/test/fixedbugs/issue16317.dir/a.go
@@ -0,0 +1,11 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+import "unsafe"
+
+func ConstUnsafePointer() unsafe.Pointer {
+ return unsafe.Pointer(uintptr(0))
+}
diff --git a/go/test/fixedbugs/issue16317.dir/b.go b/go/test/fixedbugs/issue16317.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..b81391866b254bb799deccc847d78193b3e733e1
--- /dev/null
+++ b/go/test/fixedbugs/issue16317.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+func main() {
+ _ = a.ConstUnsafePointer()
+}
diff --git a/go/test/fixedbugs/issue16616.dir/a.go b/go/test/fixedbugs/issue16616.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..0ffdbbe2681a7b058c69a4db326e19f8821cc7dd
--- /dev/null
+++ b/go/test/fixedbugs/issue16616.dir/a.go
@@ -0,0 +1,7 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type V struct{ i int }
diff --git a/go/test/fixedbugs/issue16616.dir/b.go b/go/test/fixedbugs/issue16616.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..4f238b9a25838572ec7c03a9afc10805a706f30c
--- /dev/null
+++ b/go/test/fixedbugs/issue16616.dir/b.go
@@ -0,0 +1,14 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+var V struct{ i int }
+
+var U struct {
+ a.V
+ j int
+}
diff --git a/go/test/fixedbugs/issue16616.dir/issue16616.go b/go/test/fixedbugs/issue16616.dir/issue16616.go
new file mode 100644
index 0000000000000000000000000000000000000000..0bfadb8c7459ca3615d8d079a73f9748d2b93934
--- /dev/null
+++ b/go/test/fixedbugs/issue16616.dir/issue16616.go
@@ -0,0 +1,26 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "reflect"
+
+ _ "./a"
+ "./b"
+)
+
+var V struct{ i int }
+
+func main() {
+ if got := reflect.ValueOf(b.V).Type().Field(0).PkgPath; got != "b" {
+ panic(`PkgPath=` + got + ` for first field of b.V, want "b"`)
+ }
+ if got := reflect.ValueOf(V).Type().Field(0).PkgPath; got != "main" {
+ panic(`PkgPath=` + got + ` for first field of V, want "main"`)
+ }
+ if got := reflect.ValueOf(b.U).Type().Field(0).PkgPath; got != "b" {
+ panic(`PkgPath=` + got + ` for first field of b.U, want "b"`)
+ }
+}
diff --git a/go/test/fixedbugs/issue18419.dir/other.go b/go/test/fixedbugs/issue18419.dir/other.go
new file mode 100644
index 0000000000000000000000000000000000000000..27243d297bf517eb9a807e3fe46fca9fa649dc9b
--- /dev/null
+++ b/go/test/fixedbugs/issue18419.dir/other.go
@@ -0,0 +1,11 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package other
+
+type Exported struct {
+ Member int
+}
+
+func (e *Exported) member() int { return 1 }
diff --git a/go/test/fixedbugs/issue18419.dir/test.go b/go/test/fixedbugs/issue18419.dir/test.go
new file mode 100644
index 0000000000000000000000000000000000000000..da9639dd72e30d930f4dcf5fad37ee036afd2b56
--- /dev/null
+++ b/go/test/fixedbugs/issue18419.dir/test.go
@@ -0,0 +1,15 @@
+// errorcheck -0 -m -l
+
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./other"
+
+func InMyCode(e *other.Exported) {
+ e.member() // ERROR "e\.member undefined .cannot refer to unexported field or method other\.\(\*Exported\)\.member.|unexported field or method"
+}
+
+func main() {}
diff --git a/go/test/fixedbugs/issue18895.dir/p.go b/go/test/fixedbugs/issue18895.dir/p.go
new file mode 100644
index 0000000000000000000000000000000000000000..b721f357d28996f260e2ec90ce595d5b9f26005f
--- /dev/null
+++ b/go/test/fixedbugs/issue18895.dir/p.go
@@ -0,0 +1,14 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+func F() { // ERROR "can inline"
+ var v t
+ v.m() // ERROR "inlining call"
+}
+
+type t int
+
+func (t) m() {} // ERROR "can inline"
diff --git a/go/test/fixedbugs/issue18895.dir/q.go b/go/test/fixedbugs/issue18895.dir/q.go
new file mode 100644
index 0000000000000000000000000000000000000000..1e0f2f9dfebfe87a4cd968e8cfbc2735262fb4a0
--- /dev/null
+++ b/go/test/fixedbugs/issue18895.dir/q.go
@@ -0,0 +1,11 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package q
+
+import "./p"
+
+func x() { // ERROR "can inline x"
+ p.F() // ERROR "inlining call to .*\.F" "inlining call to .*\.m"
+}
diff --git a/go/test/fixedbugs/issue18911.dir/a.go b/go/test/fixedbugs/issue18911.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..d2221e761288a26d94b0104cbaa0bd4f9e07f538
--- /dev/null
+++ b/go/test/fixedbugs/issue18911.dir/a.go
@@ -0,0 +1,7 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+var X interface{} = struct{ x int }{}
diff --git a/go/test/fixedbugs/issue18911.dir/b.go b/go/test/fixedbugs/issue18911.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..da2388b88d1b14d711fa726aecf55bf8575ed1d7
--- /dev/null
+++ b/go/test/fixedbugs/issue18911.dir/b.go
@@ -0,0 +1,21 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+import "strings"
+
+func main() {
+ defer func() {
+ p, ok := recover().(error)
+ if ok && strings.Contains(p.Error(), "different packages") {
+ return
+ }
+ panic(p)
+ }()
+
+ // expected to fail and report two identical looking (but different) types
+ _ = a.X.(struct{ x int })
+}
diff --git a/go/test/fixedbugs/issue19028.dir/a.go b/go/test/fixedbugs/issue19028.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..361251d7505df9188d33cd961632fcb513b37496
--- /dev/null
+++ b/go/test/fixedbugs/issue19028.dir/a.go
@@ -0,0 +1,9 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package reflect
+
+import "reflect"
+
+type Type reflect.Type
diff --git a/go/test/fixedbugs/issue19028.dir/main.go b/go/test/fixedbugs/issue19028.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..e2ee7b8ca1df2da8a26d4ae028b516e0f1b6dfdf
--- /dev/null
+++ b/go/test/fixedbugs/issue19028.dir/main.go
@@ -0,0 +1,26 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "reflect"
+ fake "./a" // 2nd package with name "reflect"
+)
+
+type T struct {
+ _ fake.Type
+}
+
+func (T) f() {}
+func (T) G() (_ int) { return }
+func (T) H() (_, _ int) { return }
+
+func main() {
+ var x T
+ typ := reflect.TypeOf(x)
+ for i := 0; i < typ.NumMethod(); i++ {
+ _ = typ.Method(i) // must not crash
+ }
+}
diff --git a/go/test/fixedbugs/issue19261.dir/p.go b/go/test/fixedbugs/issue19261.dir/p.go
new file mode 100644
index 0000000000000000000000000000000000000000..1c44d8a33a3236f834dafa3c296f1a26e1898fc3
--- /dev/null
+++ b/go/test/fixedbugs/issue19261.dir/p.go
@@ -0,0 +1,24 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+func F() { // ERROR "can inline F"
+ print(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
+ print(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
+ print(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
+ print(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
+ print(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
+ print(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
+}
+
+func G() {
+ F() // ERROR "inlining call to F"
+ print(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
+ print(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
+ print(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
+ print(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
+ print(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
+ print(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
+}
diff --git a/go/test/fixedbugs/issue19261.dir/q.go b/go/test/fixedbugs/issue19261.dir/q.go
new file mode 100644
index 0000000000000000000000000000000000000000..9f3550abc778da6a1e44688e03912f537984096d
--- /dev/null
+++ b/go/test/fixedbugs/issue19261.dir/q.go
@@ -0,0 +1,17 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package q
+
+import "./p"
+
+func H() {
+ p.F() // ERROR "inlining call to p.F"
+ print(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
+ print(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
+ print(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
+ print(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
+ print(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
+ print(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
+}
diff --git a/go/test/fixedbugs/issue19467.dir/mysync.go b/go/test/fixedbugs/issue19467.dir/mysync.go
new file mode 100644
index 0000000000000000000000000000000000000000..d0e6fe098937d12f5f7197dc1ed5534f2df920c3
--- /dev/null
+++ b/go/test/fixedbugs/issue19467.dir/mysync.go
@@ -0,0 +1,21 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mysync
+
+import "runtime"
+
+type WaitGroup struct {
+ Callers []uintptr
+}
+
+func (wg *WaitGroup) Add(x int) {
+ wg.Callers = make([]uintptr, 32)
+ n := runtime.Callers(1, wg.Callers)
+ wg.Callers = wg.Callers[:n]
+}
+
+func (wg *WaitGroup) Done() {
+ wg.Add(-1)
+}
diff --git a/go/test/fixedbugs/issue19467.dir/z.go b/go/test/fixedbugs/issue19467.dir/z.go
new file mode 100644
index 0000000000000000000000000000000000000000..cfbf34869cb7cd199974b44a2061ddecd0c98675
--- /dev/null
+++ b/go/test/fixedbugs/issue19467.dir/z.go
@@ -0,0 +1,35 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "log"
+ "runtime"
+
+ "./mysync"
+)
+
+func main() {
+ var wg mysync.WaitGroup
+ wg.Done()
+ ci := runtime.CallersFrames(wg.Callers)
+ frames := make([]runtime.Frame, 0, 4)
+ for {
+ frame, more := ci.Next()
+ frames = append(frames, frame)
+ if !more {
+ break
+ }
+ }
+ expecting := []string{
+ "test/mysync.(*WaitGroup).Add",
+ "test/mysync.(*WaitGroup).Done",
+ }
+ for i := 0; i < 2; i++ {
+ if frames[i].Function != expecting[i] {
+ log.Fatalf("frame %d: got %s, want %s", i, frames[i].Function, expecting[i])
+ }
+ }
+}
diff --git a/go/test/fixedbugs/issue19507.dir/div_arm.s b/go/test/fixedbugs/issue19507.dir/div_arm.s
new file mode 100644
index 0000000000000000000000000000000000000000..0bc33e92ce297f457ee8e72bd367762f0d39832b
--- /dev/null
+++ b/go/test/fixedbugs/issue19507.dir/div_arm.s
@@ -0,0 +1,12 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+TEXT ·f(SB),0,$0-8
+ MOVW x+0(FP), R1
+ MOVW x+4(FP), R2
+ DIVU R1, R2
+ DIV R1, R2
+ MODU R1, R2
+ MOD R1, R2
+ RET
diff --git a/go/test/fixedbugs/issue19507.dir/main.go b/go/test/fixedbugs/issue19507.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..e4e72be87ded8d639369de0f8212229a1248f2a2
--- /dev/null
+++ b/go/test/fixedbugs/issue19507.dir/main.go
@@ -0,0 +1,16 @@
+//go:build arm
+
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Make sure we can compile assembly with DIV and MOD in it.
+// They get rewritten to runtime calls on GOARM=5.
+
+package main
+
+func f(x, y uint32)
+
+func main() {
+ f(5, 8)
+}
diff --git a/go/test/fixedbugs/issue19548.dir/a.go b/go/test/fixedbugs/issue19548.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..3b7cd4b0e23bbaf118aadbd41097efa5c77a0f36
--- /dev/null
+++ b/go/test/fixedbugs/issue19548.dir/a.go
@@ -0,0 +1,26 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type Mode uint
+
+func (m Mode) String() string { return "mode string" }
+func (m *Mode) Addr() *Mode { return m }
+
+type Stringer interface {
+ String() string
+}
+
+var global Stringer
+var m Mode
+
+func init() {
+ // force compilation of the (*Mode).String() wrapper
+ global = &m
+}
+
+func String() string {
+ return global.String() + Mode(0).String()
+}
diff --git a/go/test/fixedbugs/issue19548.dir/b.go b/go/test/fixedbugs/issue19548.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..e5e807f43de2318e0c6a09f1132a1bdec60e8c8c
--- /dev/null
+++ b/go/test/fixedbugs/issue19548.dir/b.go
@@ -0,0 +1,24 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+type Value interface {
+ a.Stringer
+ Addr() *a.Mode
+}
+
+var global a.Mode
+
+func f() int {
+ var v Value
+ v = &global
+ return int(v.String()[0])
+}
+
+func main() {
+ f()
+}
diff --git a/go/test/fixedbugs/issue19699.dir/a.go b/go/test/fixedbugs/issue19699.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..83be926fd8d6c6c663231509614c2093f445ff41
--- /dev/null
+++ b/go/test/fixedbugs/issue19699.dir/a.go
@@ -0,0 +1,12 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func F() {
+l1:
+ if false {
+ goto l1
+ }
+}
diff --git a/go/test/fixedbugs/issue19699.dir/b.go b/go/test/fixedbugs/issue19699.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..e727133bda0d7acf0b954ee09a22a93f09a21bc0
--- /dev/null
+++ b/go/test/fixedbugs/issue19699.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+func main() {
+ a.F()
+}
diff --git a/go/test/fixedbugs/issue19764.dir/a.go b/go/test/fixedbugs/issue19764.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..64538e5bdf056ca6ce6de5d90961c17a9a49416e
--- /dev/null
+++ b/go/test/fixedbugs/issue19764.dir/a.go
@@ -0,0 +1,15 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type T struct{ _ int }
+func (t T) M() {}
+
+type I interface { M() }
+
+func F() {
+ var t I = &T{}
+ t.M() // call to the wrapper (*T).M
+}
diff --git a/go/test/fixedbugs/issue19764.dir/b.go b/go/test/fixedbugs/issue19764.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..d39f125f37c75e259eb915448d4965175bfe87a1
--- /dev/null
+++ b/go/test/fixedbugs/issue19764.dir/b.go
@@ -0,0 +1,13 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+func main() {
+ var x a.I = &a.T{}
+ x.M() // call to the wrapper (*T).M
+ a.F() // make sure a.F is not dead, which also calls (*T).M inside package a
+}
diff --git a/go/test/fixedbugs/issue20014.dir/a/a.go b/go/test/fixedbugs/issue20014.dir/a/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..1e66326276a40157352dff2ab300a8e637ea3cf7
--- /dev/null
+++ b/go/test/fixedbugs/issue20014.dir/a/a.go
@@ -0,0 +1,21 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type T struct {
+ X int `go:"track"`
+ Y int `go:"track"`
+ Z int // untracked
+}
+
+func (t *T) GetX() int {
+ return t.X
+}
+func (t *T) GetY() int {
+ return t.Y
+}
+func (t *T) GetZ() int {
+ return t.Z
+}
diff --git a/go/test/fixedbugs/issue20014.dir/main.go b/go/test/fixedbugs/issue20014.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..098ac6b99a800650805803b609d70ce8bd63cb1d
--- /dev/null
+++ b/go/test/fixedbugs/issue20014.dir/main.go
@@ -0,0 +1,60 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "sort"
+ "strings"
+
+ "issue20014.dir/a"
+)
+
+func main() {
+ samePackage()
+ crossPackage()
+
+ // Print fields registered with field tracking.
+ var fields []string
+ for _, line := range strings.Split(fieldTrackInfo, "\n") {
+ if line != "" {
+ fields = append(fields, strings.Split(line, "\t")[0])
+ }
+ }
+ sort.Strings(fields) // for stable output, regardless of optimizations
+ for _, field := range fields {
+ println(field)
+ }
+}
+
+type T struct {
+ X int `go:"track"`
+ Y int `go:"track"`
+ Z int // untracked
+}
+
+func (t *T) GetX() int {
+ return t.X
+}
+func (t *T) GetY() int {
+ return t.Y
+}
+func (t *T) GetZ() int {
+ return t.Z
+}
+
+func samePackage() {
+ var t T
+ println(t.GetX())
+ println(t.GetZ())
+}
+
+func crossPackage() {
+ var t a.T
+ println(t.GetX())
+ println(t.GetZ())
+}
+
+// This global variable is set by the linker using the -k option.
+var fieldTrackInfo string
diff --git a/go/test/fixedbugs/issue20682.dir/p.go b/go/test/fixedbugs/issue20682.dir/p.go
new file mode 100644
index 0000000000000000000000000000000000000000..fc37136d906bf26069d1fb212cd8dd7f0b60456c
--- /dev/null
+++ b/go/test/fixedbugs/issue20682.dir/p.go
@@ -0,0 +1,13 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+import "strings"
+
+type T struct{}
+
+func (T) M() {
+ strings.HasPrefix("", "")
+}
diff --git a/go/test/fixedbugs/issue20682.dir/q.go b/go/test/fixedbugs/issue20682.dir/q.go
new file mode 100644
index 0000000000000000000000000000000000000000..9554569de0d9ae05c6f11f0668ab93c488b1eea4
--- /dev/null
+++ b/go/test/fixedbugs/issue20682.dir/q.go
@@ -0,0 +1,13 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package q
+
+import "./p"
+
+type T struct{}
+
+func (T) M() interface{} {
+ return &p.T{}
+}
diff --git a/go/test/fixedbugs/issue20682.dir/r.go b/go/test/fixedbugs/issue20682.dir/r.go
new file mode 100644
index 0000000000000000000000000000000000000000..73dfe1b3af2cab0ad473d181db19b344f173817a
--- /dev/null
+++ b/go/test/fixedbugs/issue20682.dir/r.go
@@ -0,0 +1,11 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package r
+
+import "./q"
+
+type T struct {
+ q.T
+}
diff --git a/go/test/fixedbugs/issue21120.dir/a.go b/go/test/fixedbugs/issue21120.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..f2ee2526717fa863ccc0f3a959bb0c2210a77bfd
--- /dev/null
+++ b/go/test/fixedbugs/issue21120.dir/a.go
@@ -0,0 +1,13 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type S struct {
+ x int
+}
+
+func V() interface{} {
+ return S{0}
+}
diff --git a/go/test/fixedbugs/issue21120.dir/b.go b/go/test/fixedbugs/issue21120.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..b00bd53a5d58ebacff622d1f80682a0b956fb559
--- /dev/null
+++ b/go/test/fixedbugs/issue21120.dir/b.go
@@ -0,0 +1,29 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "reflect"
+
+type X int
+
+func F1() string {
+ type x X
+
+ s := struct {
+ *x
+ }{nil}
+ v := reflect.TypeOf(s)
+ return v.Field(0).PkgPath
+}
+
+func F2() string {
+ type y X
+
+ s := struct {
+ *y
+ }{nil}
+ v := reflect.TypeOf(s)
+ return v.Field(0).PkgPath
+}
diff --git a/go/test/fixedbugs/issue21120.dir/main.go b/go/test/fixedbugs/issue21120.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..1f1ec30e567200df91c8cd5339feb2aa03f22721
--- /dev/null
+++ b/go/test/fixedbugs/issue21120.dir/main.go
@@ -0,0 +1,25 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "fmt"
+ "os"
+
+ "./a"
+ "./b"
+)
+
+func main() {
+ // Make sure the reflect information for a.S is in the executable.
+ _ = a.V()
+
+ b1 := b.F1()
+ b2 := b.F2()
+ if b1 != b2 {
+ fmt.Printf("%q (from b.F1()) != %q (from b.F2())\n", b1, b2)
+ os.Exit(1)
+ }
+}
diff --git a/go/test/fixedbugs/issue22877.dir/p.go b/go/test/fixedbugs/issue22877.dir/p.go
new file mode 100644
index 0000000000000000000000000000000000000000..fc86cb9e1ebbf5cf68dddc7be491625f01128058
--- /dev/null
+++ b/go/test/fixedbugs/issue22877.dir/p.go
@@ -0,0 +1,14 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+type S struct{ i int }
+type SS = S
+
+func sub()
+
+func main() {
+ sub()
+}
diff --git a/go/test/fixedbugs/issue22877.dir/p.s b/go/test/fixedbugs/issue22877.dir/p.s
new file mode 100644
index 0000000000000000000000000000000000000000..8b14358cdc90e672666a550e975b41c3ff7fd2ae
--- /dev/null
+++ b/go/test/fixedbugs/issue22877.dir/p.s
@@ -0,0 +1,8 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "go_asm.h"
+
+TEXT ·sub(SB), 0, $0
+ RET
diff --git a/go/test/fixedbugs/issue22941.dir/a.go b/go/test/fixedbugs/issue22941.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..7a4ede438fabee33a59247a2a78cc6854165b619
--- /dev/null
+++ b/go/test/fixedbugs/issue22941.dir/a.go
@@ -0,0 +1,7 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package q
+
+type P int
diff --git a/go/test/fixedbugs/issue22941.dir/b.go b/go/test/fixedbugs/issue22941.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..87d59a6764a462ed51aedb25e730c763f0787659
--- /dev/null
+++ b/go/test/fixedbugs/issue22941.dir/b.go
@@ -0,0 +1,30 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+import q "./a"
+
+type T struct {
+ X *q.P
+}
+
+func F(in, out *T) {
+ *out = *in
+ if in.X != nil {
+ in, out := &in.X, &out.X
+ if *in == nil {
+ *out = nil
+ } else {
+ *out = new(q.P)
+ **out = **in
+ }
+ }
+ return
+}
+
+//go:noinline
+func G(x, y *T) {
+ F(x, y)
+}
diff --git a/go/test/fixedbugs/issue22941.dir/main.go b/go/test/fixedbugs/issue22941.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..84666adf0df67324eca22169f903966d6c4f302c
--- /dev/null
+++ b/go/test/fixedbugs/issue22941.dir/main.go
@@ -0,0 +1,15 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import p "./b"
+
+var G int
+
+func main() {
+ if G == 101 {
+ p.G(nil, nil)
+ }
+}
diff --git a/go/test/fixedbugs/issue22962.dir/a.go b/go/test/fixedbugs/issue22962.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..7257d7dfabb9c642857240e37d16bc9b0ec3bac4
--- /dev/null
+++ b/go/test/fixedbugs/issue22962.dir/a.go
@@ -0,0 +1,11 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func F() {
+ if x := 0; false {
+ _ = x
+ }
+}
diff --git a/go/test/fixedbugs/issue22962.dir/b.go b/go/test/fixedbugs/issue22962.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..4937ef577f37d5fb3b91908756c28d2400735681
--- /dev/null
+++ b/go/test/fixedbugs/issue22962.dir/b.go
@@ -0,0 +1,9 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+var V = func() { a.F() }
diff --git a/go/test/fixedbugs/issue23179.dir/a.go b/go/test/fixedbugs/issue23179.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..3d2816fc69d3c187c48518873278b8a3134e3788
--- /dev/null
+++ b/go/test/fixedbugs/issue23179.dir/a.go
@@ -0,0 +1,13 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type Large struct {
+ x [256]int
+}
+
+func F(x int, _ int, _ bool, _ Large) int {
+ return x
+}
diff --git a/go/test/fixedbugs/issue23179.dir/b.go b/go/test/fixedbugs/issue23179.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..4bde498cd8713a4271e3fcfcc6099ff901be7af1
--- /dev/null
+++ b/go/test/fixedbugs/issue23179.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func G(x int) int {
+ return a.F(x, 1, false, a.Large{})
+}
diff --git a/go/test/fixedbugs/issue23311.dir/main.go b/go/test/fixedbugs/issue23311.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..fa4cf76b89a7a07faff2bdc5b0506625ca607344
--- /dev/null
+++ b/go/test/fixedbugs/issue23311.dir/main.go
@@ -0,0 +1,14 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import _ "unsafe" // for linkname
+
+//go:linkname f runtime.GC
+func f()
+
+func main() {
+ f()
+}
diff --git a/go/test/fixedbugs/issue24693.dir/a.go b/go/test/fixedbugs/issue24693.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..8a845ed86ca3975d10fceb768bca7c11cc7d3b16
--- /dev/null
+++ b/go/test/fixedbugs/issue24693.dir/a.go
@@ -0,0 +1,11 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type T struct{}
+
+func (T) m() { println("FAIL") }
+
+type I interface{ m() }
diff --git a/go/test/fixedbugs/issue24693.dir/b.go b/go/test/fixedbugs/issue24693.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..15ffa4f7ca55aed3b372fa31cc70930b89a56ea6
--- /dev/null
+++ b/go/test/fixedbugs/issue24693.dir/b.go
@@ -0,0 +1,38 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+type T struct{ a.T }
+
+func (T) m() { println("ok") }
+
+// The compiler used to not pay attention to package for non-exported
+// methods when statically constructing itabs. The consequence of this
+// was that the call to b.F1(b.T{}) in c.go would create an itab using
+// a.T.m instead of b.T.m.
+func F1(i interface{ m() }) { i.m() }
+
+// The interface method calling convention depends on interface method
+// sets being sorted in the same order across compilation units. In
+// the test case below, at the call to b.F2(b.T{}) in c.go, the
+// interface method set is sorted as { a.m(); b.m() }.
+//
+// However, while compiling package b, its package path is set to "",
+// so the code produced for F2 uses { b.m(); a.m() } as the method set
+// order. So again, it ends up calling the wrong method.
+//
+// Also, this function is marked noinline because it's critical to the
+// test that the interface method call happen in this compilation
+// unit, and the itab construction happens in c.go.
+//
+//go:noinline
+func F2(i interface {
+ m()
+ a.I // embeds m() from package a
+}) {
+ i.m()
+}
diff --git a/go/test/fixedbugs/issue24693.dir/c.go b/go/test/fixedbugs/issue24693.dir/c.go
new file mode 100644
index 0000000000000000000000000000000000000000..8c6e27b140d0dbf25f322a375dc2afeb742e0738
--- /dev/null
+++ b/go/test/fixedbugs/issue24693.dir/c.go
@@ -0,0 +1,12 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./b"
+
+func main() {
+ b.F1(b.T{})
+ b.F2(b.T{})
+}
diff --git a/go/test/fixedbugs/issue24761.dir/a.go b/go/test/fixedbugs/issue24761.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..1aa2317bd5b0830d5f7e939ee6df2991f60e1c4d
--- /dev/null
+++ b/go/test/fixedbugs/issue24761.dir/a.go
@@ -0,0 +1,15 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type T2 struct{}
+
+func (t *T2) M2(a, b float64) {
+ variadic(a, b)
+}
+
+func variadic(points ...float64) {
+ println(points)
+}
diff --git a/go/test/fixedbugs/issue24761.dir/b.go b/go/test/fixedbugs/issue24761.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..dd3d543a0fc33eda6d6a20d7a363b3ae5f4b17b1
--- /dev/null
+++ b/go/test/fixedbugs/issue24761.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+type T1 struct {
+ *a.T2
+}
diff --git a/go/test/fixedbugs/issue24801.dir/a.go b/go/test/fixedbugs/issue24801.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..58e6240d8c165c097542dd082788a335d9802e05
--- /dev/null
+++ b/go/test/fixedbugs/issue24801.dir/a.go
@@ -0,0 +1,9 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type main int
+
+var X main
diff --git a/go/test/fixedbugs/issue24801.dir/main.go b/go/test/fixedbugs/issue24801.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..5c7db7b4d1f97fcecf66dbde2088edd768c3f7fd
--- /dev/null
+++ b/go/test/fixedbugs/issue24801.dir/main.go
@@ -0,0 +1,11 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+func main() {
+ a.X = 1
+}
diff --git a/go/test/fixedbugs/issue25055.dir/a.go b/go/test/fixedbugs/issue25055.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..7fea195e2b021823be067ceb39adb0f732e00364
--- /dev/null
+++ b/go/test/fixedbugs/issue25055.dir/a.go
@@ -0,0 +1,7 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+var A chan *interface{}
diff --git a/go/test/fixedbugs/issue25055.dir/b.go b/go/test/fixedbugs/issue25055.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..01efeae3e640221ac425b9a8a8d89f2de3bc885b
--- /dev/null
+++ b/go/test/fixedbugs/issue25055.dir/b.go
@@ -0,0 +1,9 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+var _ = <-a.A
diff --git a/go/test/fixedbugs/issue25984.dir/p.go b/go/test/fixedbugs/issue25984.dir/p.go
new file mode 100644
index 0000000000000000000000000000000000000000..306d6a489fd61d372c1c97b146fc940c3313f3da
--- /dev/null
+++ b/go/test/fixedbugs/issue25984.dir/p.go
@@ -0,0 +1,15 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+type m struct {
+ link *m
+}
+
+var head *m
+
+func F(m *int) bool {
+ return head != nil
+}
diff --git a/go/test/fixedbugs/issue25984.dir/q.go b/go/test/fixedbugs/issue25984.dir/q.go
new file mode 100644
index 0000000000000000000000000000000000000000..64d25870b7856c33cb04d0cc55f775b79011c02e
--- /dev/null
+++ b/go/test/fixedbugs/issue25984.dir/q.go
@@ -0,0 +1,11 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package q
+
+import "./p"
+
+func G() {
+ p.F(nil)
+}
diff --git a/go/test/fixedbugs/issue26341.dir/a.go b/go/test/fixedbugs/issue26341.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..4fd23c796ba89570d00ffca55c8b0f3e5c27b5b8
--- /dev/null
+++ b/go/test/fixedbugs/issue26341.dir/a.go
@@ -0,0 +1,11 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type k int
+
+func (k) F() {}
+
+type M map[k]int
diff --git a/go/test/fixedbugs/issue26341.dir/b.go b/go/test/fixedbugs/issue26341.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..30b8c25a5cf7c4526f6c64e0f43d653e6bab352d
--- /dev/null
+++ b/go/test/fixedbugs/issue26341.dir/b.go
@@ -0,0 +1,13 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func f() {
+ for k := range (a.M{}) {
+ k.F()
+ }
+}
diff --git "a/go/test/fixedbugs/issue27836.dir/\303\236foo.go" "b/go/test/fixedbugs/issue27836.dir/\303\236foo.go"
new file mode 100644
index 0000000000000000000000000000000000000000..ea6be0f49fdcc5d537e7126e0e7a26e185939cc2
--- /dev/null
+++ "b/go/test/fixedbugs/issue27836.dir/\303\236foo.go"
@@ -0,0 +1,17 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package Þfoo
+
+var ÞbarV int = 101
+
+func Þbar(x int) int {
+ defer func() { ÞbarV += 3 }()
+ return Þblix(x)
+}
+
+func Þblix(x int) int {
+ defer func() { ÞbarV += 9 }()
+ return ÞbarV + x
+}
diff --git "a/go/test/fixedbugs/issue27836.dir/\303\236main.go" "b/go/test/fixedbugs/issue27836.dir/\303\236main.go"
new file mode 100644
index 0000000000000000000000000000000000000000..596c620d80a321cf8c4e174ef3692d5914eef01c
--- /dev/null
+++ "b/go/test/fixedbugs/issue27836.dir/\303\236main.go"
@@ -0,0 +1,17 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "fmt"
+
+ "./Þfoo"
+ Þblix "./Þfoo"
+)
+
+func main() {
+ fmt.Printf("Þfoo.Þbar(33) returns %v\n", Þfoo.Þbar(33))
+ fmt.Printf("Þblix.Þbar(33) returns %v\n", Þblix.Þbar(33))
+}
diff --git a/go/test/fixedbugs/issue29610.dir/a.go b/go/test/fixedbugs/issue29610.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..ccbe451bca9cbfe427d0ba523e7442dd30d6b7ea
--- /dev/null
+++ b/go/test/fixedbugs/issue29610.dir/a.go
@@ -0,0 +1,15 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type I interface {
+ M(init bool)
+}
+
+var V I
+
+func init() {
+ V = nil
+}
diff --git a/go/test/fixedbugs/issue29610.dir/b.go b/go/test/fixedbugs/issue29610.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..c2016de3d05ca6ab7df42d7f20d45f5976004319
--- /dev/null
+++ b/go/test/fixedbugs/issue29610.dir/b.go
@@ -0,0 +1,17 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+type S struct {
+ a.I
+}
+
+var V a.I
+
+func init() {
+ V = S{}
+}
diff --git a/go/test/fixedbugs/issue29610.dir/main.go b/go/test/fixedbugs/issue29610.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..29437bfa618638b5f740d63a0a5893e4dce4e1d1
--- /dev/null
+++ b/go/test/fixedbugs/issue29610.dir/main.go
@@ -0,0 +1,11 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./b"
+
+var v b.S
+
+func main() {}
diff --git a/go/test/fixedbugs/issue29612.dir/main.go b/go/test/fixedbugs/issue29612.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..97415c445fa34792486e38d1b72594a3a5634a3e
--- /dev/null
+++ b/go/test/fixedbugs/issue29612.dir/main.go
@@ -0,0 +1,49 @@
+// run
+
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Do not panic on conversion to anonymous interface, which
+// is similar-looking interface types in different packages.
+
+package main
+
+import (
+ "fmt"
+
+ ssa1 "issue29612.dir/p1/ssa"
+ ssa2 "issue29612.dir/p2/ssa"
+)
+
+func main() {
+ v1 := &ssa1.T{}
+ _ = v1
+
+ v2 := &ssa2.T{}
+ ssa2.Works(v2)
+ ssa2.Panics(v2) // This call must not panic
+
+ swt(v1, 1)
+ swt(v2, 2)
+}
+
+//go:noinline
+func swt(i interface{}, want int) {
+ var got int
+ switch i.(type) {
+ case *ssa1.T:
+ got = 1
+ case *ssa2.T:
+ got = 2
+
+ case int8, int16, int32, int64:
+ got = 3
+ case uint8, uint16, uint32, uint64:
+ got = 4
+ }
+
+ if got != want {
+ panic(fmt.Sprintf("switch %v: got %d, want %d", i, got, want))
+ }
+}
diff --git a/go/test/fixedbugs/issue29612.dir/p1/ssa/ssa.go b/go/test/fixedbugs/issue29612.dir/p1/ssa/ssa.go
new file mode 100644
index 0000000000000000000000000000000000000000..8f6eb97f8f8494abcbaa4dc055e589225a9b14b6
--- /dev/null
+++ b/go/test/fixedbugs/issue29612.dir/p1/ssa/ssa.go
@@ -0,0 +1,18 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ssa
+
+type T struct{}
+
+func (T) foo() {}
+
+type fooer interface {
+ foo()
+}
+
+func Unused(v interface{}) {
+ v.(fooer).foo()
+ v.(interface{ foo() }).foo()
+}
diff --git a/go/test/fixedbugs/issue29612.dir/p2/ssa/ssa.go b/go/test/fixedbugs/issue29612.dir/p2/ssa/ssa.go
new file mode 100644
index 0000000000000000000000000000000000000000..df57314b8ce01d82d2dbe8ba1ab21b84a6211f05
--- /dev/null
+++ b/go/test/fixedbugs/issue29612.dir/p2/ssa/ssa.go
@@ -0,0 +1,28 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ssa
+
+type T struct{}
+
+func (T) foo() {}
+
+type fooer interface {
+ foo()
+}
+
+func Works(v interface{}) {
+ switch v.(type) {
+ case interface{}:
+ v.(fooer).foo()
+ }
+}
+
+func Panics(v interface{}) {
+ switch v.(type) {
+ case interface{}:
+ v.(fooer).foo()
+ v.(interface{ foo() }).foo()
+ }
+}
diff --git a/go/test/fixedbugs/issue29919.dir/a.go b/go/test/fixedbugs/issue29919.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..3b1dac40aab0ce3f0f07c47cd8d9e9491f80db6f
--- /dev/null
+++ b/go/test/fixedbugs/issue29919.dir/a.go
@@ -0,0 +1,75 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Make sure tracebacks from initialization code are reported correctly.
+
+package a
+
+import (
+ "fmt"
+ "runtime"
+ "strings"
+)
+
+var x = f() // line 15
+
+func f() int {
+ var b [4096]byte
+ n := runtime.Stack(b[:], false) // line 19
+ s := string(b[:n])
+ var pcs [10]uintptr
+ n = runtime.Callers(1, pcs[:]) // line 22
+
+ // Check the Stack results.
+ if debug {
+ println(s)
+ }
+ if strings.Contains(s, "autogenerated") {
+ panic("autogenerated code in traceback")
+ }
+ if !strings.Contains(s, "a.go:15") {
+ panic("missing a.go:15")
+ }
+ if !strings.Contains(s, "a.go:19") {
+ panic("missing a.go:19")
+ }
+ if !strings.Contains(s, "a.init") {
+ panic("missing a.init")
+ }
+
+ // Check the CallersFrames results.
+ if debug {
+ iter := runtime.CallersFrames(pcs[:n])
+ for {
+ f, more := iter.Next()
+ fmt.Printf("%s %s:%d\n", f.Function, f.File, f.Line)
+ if !more {
+ break
+ }
+ }
+ }
+ iter := runtime.CallersFrames(pcs[:n])
+ f, more := iter.Next()
+ if f.Function != "test/a.f" || !strings.HasSuffix(f.File, "a.go") || f.Line != 22 {
+ panic(fmt.Sprintf("bad f %v\n", f))
+ }
+ if !more {
+ panic("traceback truncated after f")
+ }
+ f, more = iter.Next()
+ if f.Function != "test/a.init" || !strings.HasSuffix(f.File, "a.go") || f.Line != 15 {
+ panic(fmt.Sprintf("bad init %v\n", f))
+ }
+ if !more {
+ panic("traceback truncated after init")
+ }
+ f, _ = iter.Next()
+ if !strings.HasPrefix(f.Function, "runtime.") {
+ panic("runtime. driver missing")
+ }
+
+ return 0
+}
+
+const debug = false
diff --git a/go/test/fixedbugs/issue29919.dir/main.go b/go/test/fixedbugs/issue29919.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..3e99ca891b55dce6ab6f75646e22d674fcafe705
--- /dev/null
+++ b/go/test/fixedbugs/issue29919.dir/main.go
@@ -0,0 +1,10 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import _ "./a"
+
+func main() {
+}
diff --git a/go/test/fixedbugs/issue30659.dir/a.go b/go/test/fixedbugs/issue30659.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..3837e021c4817381de7aaa3a0e7f76987777fb09
--- /dev/null
+++ b/go/test/fixedbugs/issue30659.dir/a.go
@@ -0,0 +1,19 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type I interface {
+ I2
+}
+type I2 interface {
+ M()
+}
+type S struct{}
+
+func (*S) M() {}
+
+func New() I {
+ return &S{}
+}
diff --git a/go/test/fixedbugs/issue30659.dir/b.go b/go/test/fixedbugs/issue30659.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..272e520582e8f02c88e564b8e118aae99964a495
--- /dev/null
+++ b/go/test/fixedbugs/issue30659.dir/b.go
@@ -0,0 +1,13 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import (
+ "./a"
+)
+
+func B(p1 a.I, p2 a.I2) int {
+ return 42
+}
diff --git a/go/test/fixedbugs/issue30862.dir/a/a.go b/go/test/fixedbugs/issue30862.dir/a/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..c23f4de1efd1a91bdf42ab66e1dd3afe551fdafc
--- /dev/null
+++ b/go/test/fixedbugs/issue30862.dir/a/a.go
@@ -0,0 +1,15 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+var pl int
+
+type NoitfStruct struct {
+ F int
+ G int
+}
+
+//go:nointerface
+func (t *NoitfStruct) NoInterfaceMethod() {}
diff --git a/go/test/fixedbugs/issue30862.dir/b/b.go b/go/test/fixedbugs/issue30862.dir/b/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..230221d5036248af1c1c80415a675cc55f8ee16e
--- /dev/null
+++ b/go/test/fixedbugs/issue30862.dir/b/b.go
@@ -0,0 +1,29 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "issue30862.dir/a"
+
+type EmbedImported struct {
+ a.NoitfStruct
+}
+
+func Test() []string {
+ bad := []string{}
+ x := interface{}(new(a.NoitfStruct))
+ if _, ok := x.(interface {
+ NoInterfaceMethod()
+ }); ok {
+ bad = append(bad, "fail 1")
+ }
+
+ x = interface{}(new(EmbedImported))
+ if _, ok := x.(interface {
+ NoInterfaceMethod()
+ }); ok {
+ bad = append(bad, "fail 2")
+ }
+ return bad
+}
diff --git a/go/test/fixedbugs/issue30862.dir/main.go b/go/test/fixedbugs/issue30862.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..1489c5a34255fbb01b93700bd1150d90de93920a
--- /dev/null
+++ b/go/test/fixedbugs/issue30862.dir/main.go
@@ -0,0 +1,28 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "fmt"
+ "os"
+
+ "issue30862.dir/b"
+)
+
+// Test case for issue 30862.
+
+// Be aware that unless GOEXPERIMENT=fieldtrack is set when building
+// the compiler, this test will fail if executed with a regular GC
+// compiler.
+
+func main() {
+ bad := b.Test()
+ if len(bad) > 0 {
+ for _, s := range bad {
+ fmt.Fprintf(os.Stderr, "test failed: %s\n", s)
+ }
+ os.Exit(1)
+ }
+}
diff --git a/go/test/fixedbugs/issue30907.dir/a.go b/go/test/fixedbugs/issue30907.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..e1a5c0cc3b6fbea2d4d8fc9835ce7ee3b8c4bb33
--- /dev/null
+++ b/go/test/fixedbugs/issue30907.dir/a.go
@@ -0,0 +1,19 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type UUID string
+
+func New() UUID {
+ return Must(NewRandom())
+}
+
+func NewRandom() (UUID, error) {
+ return "", nil
+}
+
+func Must(uuid UUID, err error) UUID {
+ return uuid
+}
diff --git a/go/test/fixedbugs/issue30907.dir/b.go b/go/test/fixedbugs/issue30907.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..f4f5fc4fdd12714522a02d41543bdd7e08aaf6df
--- /dev/null
+++ b/go/test/fixedbugs/issue30907.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+import "./a"
+
+func F() {
+ a.New()
+}
diff --git a/go/test/fixedbugs/issue30908.dir/a.go b/go/test/fixedbugs/issue30908.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..2f0abc3780c2a11fe8d0f560f9b7dac8ba229ecc
--- /dev/null
+++ b/go/test/fixedbugs/issue30908.dir/a.go
@@ -0,0 +1,32 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+import (
+ "errors"
+ "strings"
+)
+
+var G interface{}
+
+func Unmarshal(data []byte, o interface{}) error {
+ G = o
+ v, ok := o.(*map[string]interface{})
+ if !ok {
+ return errors.New("eek")
+ }
+ vals := make(map[string]interface{})
+ s := string(data)
+ items := strings.Split(s, " ")
+ var err error
+ for _, item := range items {
+ vals[item] = s
+ if item == "error" {
+ err = errors.New("ouch")
+ }
+ }
+ *v = vals
+ return err
+}
diff --git a/go/test/fixedbugs/issue30908.dir/b.go b/go/test/fixedbugs/issue30908.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..2f543985b4fc39ccd24eba19ffd7ea0a1252496f
--- /dev/null
+++ b/go/test/fixedbugs/issue30908.dir/b.go
@@ -0,0 +1,35 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import (
+ "io/ioutil"
+
+ "./a"
+)
+
+var G int
+
+// An inlinable function. To trigger the bug in question this needs
+// to be inlined here within the package and also inlined into some
+// other package that imports it.
+func ReadValues(data []byte) (vals map[string]interface{}, err error) {
+ err = a.Unmarshal(data, &vals)
+ if len(vals) == 0 {
+ vals = map[string]interface{}{}
+ }
+ return
+}
+
+// A local call to the function above, which triggers the "move to heap"
+// of the output param.
+func CallReadValues(filename string) (map[string]interface{}, error) {
+ defer func() { G++ }()
+ data, err := ioutil.ReadFile(filename)
+ if err != nil {
+ return map[string]interface{}{}, err
+ }
+ return ReadValues(data)
+}
diff --git a/go/test/fixedbugs/issue30908.dir/m.go b/go/test/fixedbugs/issue30908.dir/m.go
new file mode 100644
index 0000000000000000000000000000000000000000..a170a6eed6fca31f4253f96ca5d29c8a725ab12d
--- /dev/null
+++ b/go/test/fixedbugs/issue30908.dir/m.go
@@ -0,0 +1,21 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "os"
+
+ "./b"
+)
+
+func main() {
+ seed := "some things are better"
+ bsl := []byte(seed)
+ b.CallReadValues("/dev/null")
+ vals, err := b.ReadValues(bsl)
+ if vals["better"] != seed || err != nil {
+ os.Exit(1)
+ }
+}
diff --git a/go/test/fixedbugs/issue31053.dir/f1.go b/go/test/fixedbugs/issue31053.dir/f1.go
new file mode 100644
index 0000000000000000000000000000000000000000..610f393818872d07b48650c0f7d6825033b36e30
--- /dev/null
+++ b/go/test/fixedbugs/issue31053.dir/f1.go
@@ -0,0 +1,18 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package f1
+
+type Foo struct {
+ doneChan chan bool
+ Name string
+ fOO int
+ hook func()
+}
+
+func (f *Foo) Exported() {
+}
+
+func (f *Foo) unexported() {
+}
diff --git a/go/test/fixedbugs/issue31053.dir/main.go b/go/test/fixedbugs/issue31053.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..3bc75d17d2d80b660d00fda696a2516333478bc8
--- /dev/null
+++ b/go/test/fixedbugs/issue31053.dir/main.go
@@ -0,0 +1,42 @@
+// errorcheck
+
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+import "./f1"
+
+func main() {
+ f := f1.Foo{
+ doneChan: nil, // ERROR "cannot refer to unexported field 'doneChan' in struct literal of type f1.Foo"
+ DoneChan: nil, // ERROR "unknown field 'DoneChan' in struct literal of type f1.Foo"
+ Name: "hey",
+ name: "there", // ERROR "unknown field 'name' in struct literal of type f1.Foo .but does have Name."
+ noSuchPrivate: true, // ERROR "unknown field 'noSuchPrivate' in struct literal of type f1.Foo"
+ NoSuchPublic: true, // ERROR "unknown field 'NoSuchPublic' in struct literal of type f1.Foo"
+ foo: true, // ERROR "unknown field 'foo' in struct literal of type f1.Foo"
+ hook: func() {}, // ERROR "cannot refer to unexported field 'hook' in struct literal of type f1.Foo"
+ unexported: func() {}, // ERROR "unknown field 'unexported' in struct literal of type f1.Foo"
+ Exported: func() {}, // ERROR "unknown field 'Exported' in struct literal of type f1.Foo"
+ }
+ f.doneChan = nil // ERROR "f.doneChan undefined .cannot refer to unexported field or method doneChan."
+ f.DoneChan = nil // ERROR "f.DoneChan undefined .type f1.Foo has no field or method DoneChan."
+ f.name = nil // ERROR "f.name undefined .type f1.Foo has no field or method name, but does have Name."
+
+ _ = f.doneChan // ERROR "f.doneChan undefined .cannot refer to unexported field or method doneChan."
+ _ = f.DoneChan // ERROR "f.DoneChan undefined .type f1.Foo has no field or method DoneChan."
+ _ = f.Name
+ _ = f.name // ERROR "f.name undefined .type f1.Foo has no field or method name, but does have Name."
+ _ = f.noSuchPrivate // ERROR "f.noSuchPrivate undefined .type f1.Foo has no field or method noSuchPrivate."
+ _ = f.NoSuchPublic // ERROR "f.NoSuchPublic undefined .type f1.Foo has no field or method NoSuchPublic."
+ _ = f.foo // ERROR "f.foo undefined .type f1.Foo has no field or method foo."
+ _ = f.Exported
+ _ = f.exported // ERROR "f.exported undefined .type f1.Foo has no field or method exported, but does have Exported."
+ _ = f.Unexported // ERROR "f.Unexported undefined .type f1.Foo has no field or method Unexported."
+ _ = f.unexported // ERROR "f.unexported undefined .cannot refer to unexported field or method unexported."
+ f.unexported = 10 // ERROR "f.unexported undefined .cannot refer to unexported field or method unexported."
+ f.unexported() // ERROR "f.unexported undefined .cannot refer to unexported field or method unexported."
+ _ = f.hook // ERROR "f.hook undefined .cannot refer to unexported field or method hook."
+}
diff --git a/go/test/fixedbugs/issue31252.dir/a.go b/go/test/fixedbugs/issue31252.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..fa431502c087b88f118646f84cf5904fa8edeeaf
--- /dev/null
+++ b/go/test/fixedbugs/issue31252.dir/a.go
@@ -0,0 +1,13 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+import "fmt"
+
+type IndexController struct{}
+
+func (this *IndexController) Index(m *string) {
+ fmt.Println(m)
+}
diff --git a/go/test/fixedbugs/issue31252.dir/b.go b/go/test/fixedbugs/issue31252.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..9bfc0ff92eabf7c8fc84b5d2eb3b95f216813edd
--- /dev/null
+++ b/go/test/fixedbugs/issue31252.dir/b.go
@@ -0,0 +1,13 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "fmt"
+
+type IndexController struct{}
+
+func (this *IndexController) Index(m *string) {
+ fmt.Println(m)
+}
diff --git a/go/test/fixedbugs/issue31252.dir/c.go b/go/test/fixedbugs/issue31252.dir/c.go
new file mode 100644
index 0000000000000000000000000000000000000000..98ecf6117720c6d115ccbe2d75ea3a23aa74df8a
--- /dev/null
+++ b/go/test/fixedbugs/issue31252.dir/c.go
@@ -0,0 +1,26 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package c
+
+import (
+ "./a"
+ "./b"
+)
+
+type HandlerFunc func(*string)
+
+func RouterInit() {
+ //home API
+ homeIndex := &a.IndexController{}
+ GET("/home/index/index", homeIndex.Index)
+ //admin API
+ adminIndex := &b.IndexController{}
+ GET("/admin/index/index", adminIndex.Index)
+ return
+}
+
+func GET(path string, handlers ...HandlerFunc) {
+ return
+}
diff --git a/go/test/fixedbugs/issue31252.dir/main.go b/go/test/fixedbugs/issue31252.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..6c0c9ce5d2c380029ab9cedd19c947069ee88d9e
--- /dev/null
+++ b/go/test/fixedbugs/issue31252.dir/main.go
@@ -0,0 +1,11 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./c"
+
+func main() {
+ c.RouterInit()
+}
diff --git a/go/test/fixedbugs/issue31636.dir/a.go b/go/test/fixedbugs/issue31636.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..e57e0d5fb7dd87d70de60e769b54e7ec2276822f
--- /dev/null
+++ b/go/test/fixedbugs/issue31636.dir/a.go
@@ -0,0 +1,9 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func init() {
+ println("a")
+}
diff --git a/go/test/fixedbugs/issue31636.dir/b.go b/go/test/fixedbugs/issue31636.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..990e68209b9903522f324bad2cdde5c270e3c5ce
--- /dev/null
+++ b/go/test/fixedbugs/issue31636.dir/b.go
@@ -0,0 +1,9 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+func init() {
+ println("b")
+}
diff --git a/go/test/fixedbugs/issue31636.dir/c.go b/go/test/fixedbugs/issue31636.dir/c.go
new file mode 100644
index 0000000000000000000000000000000000000000..e53529aa591271e84a714e128770eabdef8b92e8
--- /dev/null
+++ b/go/test/fixedbugs/issue31636.dir/c.go
@@ -0,0 +1,9 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package c
+
+func init() {
+ println("c")
+}
diff --git a/go/test/fixedbugs/issue31636.dir/main.go b/go/test/fixedbugs/issue31636.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..bbc58369d3fcd6b640c682a2ac0ea679125ade5b
--- /dev/null
+++ b/go/test/fixedbugs/issue31636.dir/main.go
@@ -0,0 +1,20 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+// We want the initializers of these packages to occur in source code
+// order. See issue 31636. This is the behavior up to and including
+// 1.13. For 1.14, we will move to a variant of lexicographic ordering
+// which will require a change to the test output of this test.
+import (
+ _ "./c"
+
+ _ "./b"
+
+ _ "./a"
+)
+
+func main() {
+}
diff --git a/go/test/fixedbugs/issue31637.dir/a.go b/go/test/fixedbugs/issue31637.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..71f392697c4967a2d384c56e0667636b109b9782
--- /dev/null
+++ b/go/test/fixedbugs/issue31637.dir/a.go
@@ -0,0 +1,15 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type dO struct {
+ x int
+}
+
+type EDO struct{}
+
+func (EDO) Apply(*dO) {}
+
+var X EDO
diff --git a/go/test/fixedbugs/issue31637.dir/b.go b/go/test/fixedbugs/issue31637.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..ce83b000df8376167409ad531ff82456db1d10b5
--- /dev/null
+++ b/go/test/fixedbugs/issue31637.dir/b.go
@@ -0,0 +1,19 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+type No struct {
+ a.EDO
+}
+
+func X() No {
+ return No{}
+}
+
+func main() {
+ X()
+}
diff --git a/go/test/fixedbugs/issue31959.dir/a.go b/go/test/fixedbugs/issue31959.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..6c7ffa38c12b8268c54e371c3860313a847938cc
--- /dev/null
+++ b/go/test/fixedbugs/issue31959.dir/a.go
@@ -0,0 +1,12 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type T struct{}
+
+func F() {
+ type T = int
+ println(T(0))
+}
diff --git a/go/test/fixedbugs/issue31959.dir/main.go b/go/test/fixedbugs/issue31959.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..6604e3abbdaa4c9d44ace2cc8a691bb15bef7f71
--- /dev/null
+++ b/go/test/fixedbugs/issue31959.dir/main.go
@@ -0,0 +1,21 @@
+// run
+
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Check import package contains type alias in function
+// with the same name with an export type not panic
+
+package main
+
+import (
+ "fmt"
+
+ "./a"
+)
+
+func main() {
+ fmt.Println(a.T{})
+ a.F()
+}
diff --git a/go/test/fixedbugs/issue32595.dir/a.go b/go/test/fixedbugs/issue32595.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..8342dd5cbcff84c39e6fcdb142c6ddf94bdcd122
--- /dev/null
+++ b/go/test/fixedbugs/issue32595.dir/a.go
@@ -0,0 +1,9 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func A() {
+ defer func() {}()
+}
diff --git a/go/test/fixedbugs/issue32595.dir/b.go b/go/test/fixedbugs/issue32595.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..9a13a575a87ff4b07da757e8b6e3ecb4e2aa3a34
--- /dev/null
+++ b/go/test/fixedbugs/issue32595.dir/b.go
@@ -0,0 +1,15 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "reflect"
+
+func B() {
+ t1 := reflect.TypeOf([0]byte{})
+ t2 := reflect.TypeOf(new([0]byte)).Elem()
+ if t1 != t2 {
+ panic("[0]byte types do not match")
+ }
+}
diff --git a/go/test/fixedbugs/issue32595.dir/main.go b/go/test/fixedbugs/issue32595.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..979efe3a910fec6d8e8b4778605dbdaaad8d3010
--- /dev/null
+++ b/go/test/fixedbugs/issue32595.dir/main.go
@@ -0,0 +1,15 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./a"
+ "./b"
+)
+
+func main() {
+ a.A()
+ b.B()
+}
diff --git a/go/test/fixedbugs/issue32778.dir/a.go b/go/test/fixedbugs/issue32778.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..1e6ac012334c507be36315a7b03cbeba47c42696
--- /dev/null
+++ b/go/test/fixedbugs/issue32778.dir/a.go
@@ -0,0 +1,18 @@
+// Copyright 2019 The Go Authors. All rights reserved. Use of this
+// source code is governed by a BSD-style license that can be found in
+// the LICENSE file.
+
+package a
+
+import "strings"
+
+type Name string
+
+type FullName string
+
+func (n FullName) Name() Name {
+ if i := strings.LastIndexByte(string(n), '.'); i >= 0 {
+ return Name(n[i+1:])
+ }
+ return Name(n)
+}
diff --git a/go/test/fixedbugs/issue32778.dir/b.go b/go/test/fixedbugs/issue32778.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..a0ee398d268c3ff7475652e68362fba66953b9b1
--- /dev/null
+++ b/go/test/fixedbugs/issue32778.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2019 The Go Authors. All rights reserved. Use of this
+// source code is governed by a BSD-style license that can be found in
+// the LICENSE file.
+
+package b
+
+import "./a"
+
+func Expo(fn a.FullName) a.Name {
+ return fn.Name()
+}
diff --git a/go/test/fixedbugs/issue32901.dir/a.go b/go/test/fixedbugs/issue32901.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..54ed7713f6432a729c6e72005e0025197d518189
--- /dev/null
+++ b/go/test/fixedbugs/issue32901.dir/a.go
@@ -0,0 +1,15 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type T struct { x int }
+
+func F() interface{} {
+ return [2]T{}
+}
+
+func P() interface{} {
+ return &[2]T{}
+}
diff --git a/go/test/fixedbugs/issue32901.dir/b.go b/go/test/fixedbugs/issue32901.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..932d7b0afa53f05266e65476ce1f92e744a870d2
--- /dev/null
+++ b/go/test/fixedbugs/issue32901.dir/b.go
@@ -0,0 +1,15 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func F() interface{} {
+ return a.F()
+}
+
+func P() interface{} {
+ return a.P()
+}
diff --git a/go/test/fixedbugs/issue32901.dir/c.go b/go/test/fixedbugs/issue32901.dir/c.go
new file mode 100644
index 0000000000000000000000000000000000000000..5f31c7ff028b6dc0d05af923e4e5d58d1edb419b
--- /dev/null
+++ b/go/test/fixedbugs/issue32901.dir/c.go
@@ -0,0 +1,17 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package c
+
+import "./b"
+
+func F() interface{} {
+ go func(){}() // make it non-inlineable
+ return b.F()
+}
+
+func P() interface{} {
+ go func(){}() // make it non-inlineable
+ return b.P()
+}
diff --git a/go/test/fixedbugs/issue32901.dir/main.go b/go/test/fixedbugs/issue32901.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..673c6ab3e0f894b886f459f1cd10ba38e52688bd
--- /dev/null
+++ b/go/test/fixedbugs/issue32901.dir/main.go
@@ -0,0 +1,21 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "reflect"
+
+ "./c"
+)
+
+func main() {
+ x := c.F()
+ p := c.P()
+ t := reflect.PointerTo(reflect.TypeOf(x))
+ tp := reflect.TypeOf(p)
+ if t != tp {
+ panic("FAIL")
+ }
+}
diff --git a/go/test/fixedbugs/issue32922.dir/a.go b/go/test/fixedbugs/issue32922.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..b13c4b404d13bb2fa3eae332000f9d963ee5f524
--- /dev/null
+++ b/go/test/fixedbugs/issue32922.dir/a.go
@@ -0,0 +1,18 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func A() int {
+ return p("count")
+}
+
+func p(which string, args ...string) int {
+ switch which {
+ case "count", "something":
+ return 1
+ default:
+ return 2
+ }
+}
diff --git a/go/test/fixedbugs/issue32922.dir/b.go b/go/test/fixedbugs/issue32922.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..fdaf42d3dff4ebd35bd664e348956f5f3349759c
--- /dev/null
+++ b/go/test/fixedbugs/issue32922.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func B() int {
+ return 99 + a.A()
+}
diff --git a/go/test/fixedbugs/issue33013.dir/a.go b/go/test/fixedbugs/issue33013.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..056be88aeac9c7e9817e09c9ccfd69e05c74ae5f
--- /dev/null
+++ b/go/test/fixedbugs/issue33013.dir/a.go
@@ -0,0 +1,9 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type G interface {
+ UsesEmpty(p interface{}) int
+}
diff --git a/go/test/fixedbugs/issue33013.dir/b.go b/go/test/fixedbugs/issue33013.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..a8f5cc0650551d98a762e1751d91f24a2e719fd7
--- /dev/null
+++ b/go/test/fixedbugs/issue33013.dir/b.go
@@ -0,0 +1,24 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+type Service uint64
+type ServiceDesc struct {
+ X int
+ uc
+}
+
+type uc interface {
+ f() a.G
+}
+
+var q int
+
+func RS(svcd *ServiceDesc, server interface{}, qq uint8) *Service {
+ defer func() { q += int(qq) }()
+ return nil
+}
diff --git a/go/test/fixedbugs/issue33013.dir/c.go b/go/test/fixedbugs/issue33013.dir/c.go
new file mode 100644
index 0000000000000000000000000000000000000000..74425dfaae10fd77860b6ecc10d7e25ac7519af8
--- /dev/null
+++ b/go/test/fixedbugs/issue33013.dir/c.go
@@ -0,0 +1,19 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package c
+
+import (
+ "./a"
+ "./b"
+)
+
+type BI interface {
+ Something(s int64) int64
+ Another(pxp a.G) int32
+}
+
+func BRS(sd *b.ServiceDesc, server BI, xyz int) *b.Service {
+ return b.RS(sd, server, 7)
+}
diff --git a/go/test/fixedbugs/issue33013.dir/d.go b/go/test/fixedbugs/issue33013.dir/d.go
new file mode 100644
index 0000000000000000000000000000000000000000..c70c6647e8ccb4ae08d6dd4581548694549113f9
--- /dev/null
+++ b/go/test/fixedbugs/issue33013.dir/d.go
@@ -0,0 +1,16 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package d
+
+import (
+ "./b"
+ "./c"
+)
+
+var GA b.Service
+
+func C() {
+ c.BRS(nil, nil, 22)
+}
diff --git a/go/test/fixedbugs/issue33020.dir/a.go b/go/test/fixedbugs/issue33020.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..948f4fdf3b2af3fb006f47862ede5a8b8da90775
--- /dev/null
+++ b/go/test/fixedbugs/issue33020.dir/a.go
@@ -0,0 +1,16 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+var G1 int
+var G2 int
+var G3 int
+var G4 int
+var G5 int
+var G6 int
+var G7 int
+var G8 int
+var G9 int
+var G10 int
diff --git a/go/test/fixedbugs/issue33020.dir/b.go b/go/test/fixedbugs/issue33020.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..14a2a87041e0d869ac814210cdc3f41e5eff5e67
--- /dev/null
+++ b/go/test/fixedbugs/issue33020.dir/b.go
@@ -0,0 +1,22 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+var N n
+
+type n struct{}
+
+func (r n) M1() int { return a.G1 }
+func (r n) M2() int { return a.G2 }
+func (r n) M3() int { return a.G3 }
+func (r n) M4() int { return a.G4 }
+func (r n) M5() int { return a.G5 }
+func (r n) M6() int { return a.G6 }
+func (r n) M7() int { return a.G7 }
+func (r n) M8() int { return a.G8 }
+func (r n) M9() int { return a.G9 }
+func (r n) M10() int { return a.G10 }
diff --git a/go/test/fixedbugs/issue33020a.dir/a.go b/go/test/fixedbugs/issue33020a.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..91764982dc456a26f42ffd042c8945ae7881deed
--- /dev/null
+++ b/go/test/fixedbugs/issue33020a.dir/a.go
@@ -0,0 +1,13 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type FArg func(args []string) error
+
+type Command struct {
+ Name string
+ Arg1 FArg
+ Arg2 func(args []string) error
+}
diff --git a/go/test/fixedbugs/issue33020a.dir/b.go b/go/test/fixedbugs/issue33020a.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..5b0f9d86d72acd9cb40ae5d3d8ba2606df8c0f40
--- /dev/null
+++ b/go/test/fixedbugs/issue33020a.dir/b.go
@@ -0,0 +1,14 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+var Cmd = &a.Command{
+ Name: "test",
+}
+
+func main() {
+}
diff --git a/go/test/fixedbugs/issue33158.dir/a.go b/go/test/fixedbugs/issue33158.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..28714e0c991e8936bea5d1dcf09b697ed71690fb
--- /dev/null
+++ b/go/test/fixedbugs/issue33158.dir/a.go
@@ -0,0 +1,25 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+var GS string
+
+func M() string {
+ if s := getname("Fred"); s != "" {
+ return s
+ }
+ if s := getname("Joe"); s != "" {
+ return s
+ }
+
+ return string("Alex")
+}
+
+// getname can be any function returning a string, just has to be non-inlinable.
+
+//go:noinline
+func getname(s string) string {
+ return s + "foo"
+}
diff --git a/go/test/fixedbugs/issue33158.dir/b.go b/go/test/fixedbugs/issue33158.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..4174b417ec174f9cbde3457b6fbf679a09300c0e
--- /dev/null
+++ b/go/test/fixedbugs/issue33158.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func B() string {
+ return a.M()
+}
diff --git a/go/test/fixedbugs/issue33219.dir/a.go b/go/test/fixedbugs/issue33219.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..2d96301f9cfedbf07d92159b18e2ba0a6436c525
--- /dev/null
+++ b/go/test/fixedbugs/issue33219.dir/a.go
@@ -0,0 +1,17 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type A interface {
+ M(i interface{}) interface{}
+}
+
+var a1 A
+var a2 A
+
+func V(p A, k, v interface{}) A {
+ defer func() { a1, a2 = a2, a1 }()
+ return a1
+}
diff --git a/go/test/fixedbugs/issue33219.dir/b.go b/go/test/fixedbugs/issue33219.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..2a8f518bef5c3b00af88386961851ee6617e7f52
--- /dev/null
+++ b/go/test/fixedbugs/issue33219.dir/b.go
@@ -0,0 +1,25 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+type Service uint64
+
+var q *Service
+var r *Service
+
+type f struct{}
+
+var fk f
+
+func No(s a.A, qq uint8) *Service {
+ defer func() { q, r = r, q }()
+ return q
+}
+
+func Yes(s a.A, p *uint64) a.A {
+ return a.V(s, fk, p)
+}
diff --git a/go/test/fixedbugs/issue33219.dir/c.go b/go/test/fixedbugs/issue33219.dir/c.go
new file mode 100644
index 0000000000000000000000000000000000000000..a78fe69a9e948d2bcbcc78aab948b4f45019a794
--- /dev/null
+++ b/go/test/fixedbugs/issue33219.dir/c.go
@@ -0,0 +1,20 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package c
+
+import (
+ "./a"
+ "./b"
+)
+
+type BI interface {
+ Another(pxp a.A) int32
+}
+
+//go:noinline
+func BRS(sd a.A, xyz int) *b.Service {
+ x := b.Yes(sd, nil)
+ return b.No(x, 1)
+}
diff --git a/go/test/fixedbugs/issue33739.dir/a.go b/go/test/fixedbugs/issue33739.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..7eb5b927c498872039e41bdd0a9588e48a5fd0e1
--- /dev/null
+++ b/go/test/fixedbugs/issue33739.dir/a.go
@@ -0,0 +1,11 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func F() func() {
+ return f
+}
+
+func f() {}
diff --git a/go/test/fixedbugs/issue33739.dir/b.go b/go/test/fixedbugs/issue33739.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..d22fe34d668d97c1f69c1359a05dc8cb911ff2c7
--- /dev/null
+++ b/go/test/fixedbugs/issue33739.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+func main() {
+ a.F()()
+}
diff --git a/go/test/fixedbugs/issue33866.dir/a.go b/go/test/fixedbugs/issue33866.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..9c782c5eedf37c331a0b307fc43f22d5b3ac8fcf
--- /dev/null
+++ b/go/test/fixedbugs/issue33866.dir/a.go
@@ -0,0 +1,18 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type Builder struct {
+ x int
+}
+
+func (tb Builder) Build() (out struct {
+ x interface{}
+ s string
+}) {
+ out.x = nil
+ out.s = "hello!"
+ return
+}
diff --git a/go/test/fixedbugs/issue33866.dir/b.go b/go/test/fixedbugs/issue33866.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..aa2a32271c738a922412591472a8ae9308a93c71
--- /dev/null
+++ b/go/test/fixedbugs/issue33866.dir/b.go
@@ -0,0 +1,15 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+type (
+ ABuilder = a.Builder
+)
+
+func Bfunc() ABuilder {
+ return ABuilder{}
+}
diff --git a/go/test/fixedbugs/issue34503.dir/a.go b/go/test/fixedbugs/issue34503.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..2c149135ad6d4bffb5116a2d27c90489d7b1e056
--- /dev/null
+++ b/go/test/fixedbugs/issue34503.dir/a.go
@@ -0,0 +1,15 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+import "unsafe"
+
+type HookFunc func(x uint64)
+
+var HookV unsafe.Pointer
+
+func Hook(x uint64) {
+ (*(*HookFunc)(HookV))(x)
+}
diff --git a/go/test/fixedbugs/issue34503.dir/b.go b/go/test/fixedbugs/issue34503.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..7ea02511b06e78d721781297352e6dfc99fd120a
--- /dev/null
+++ b/go/test/fixedbugs/issue34503.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func Bfunc() {
+ a.Hook(101)
+}
diff --git a/go/test/fixedbugs/issue34577.dir/a.go b/go/test/fixedbugs/issue34577.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..b6af5556b3c832d874471ff8261239cee65438e3
--- /dev/null
+++ b/go/test/fixedbugs/issue34577.dir/a.go
@@ -0,0 +1,27 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type A struct {
+ x int
+}
+
+type AI interface {
+ bar()
+}
+
+type AC int
+
+func (ab AC) bar() {
+}
+
+const (
+ ACC = AC(101)
+)
+
+//go:noinline
+func W(a A, k, v interface{}) A {
+ return A{3}
+}
diff --git a/go/test/fixedbugs/issue34577.dir/b.go b/go/test/fixedbugs/issue34577.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..c61d7da78209709f7464924e49fa8b692dadc7bb
--- /dev/null
+++ b/go/test/fixedbugs/issue34577.dir/b.go
@@ -0,0 +1,23 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+type B struct {
+ s string
+}
+
+func (b B) Func(x a.A) a.A {
+ return a.W(x, k, b)
+}
+
+type ktype int
+
+const k ktype = 0
+
+func Func2() a.AI {
+ return a.ACC
+}
diff --git a/go/test/fixedbugs/issue3552.dir/one.go b/go/test/fixedbugs/issue3552.dir/one.go
new file mode 100644
index 0000000000000000000000000000000000000000..e594db7478bbf32af3fe9eef0232cdda23545d57
--- /dev/null
+++ b/go/test/fixedbugs/issue3552.dir/one.go
@@ -0,0 +1,28 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package one
+
+// Issue 3552
+
+type T struct { int }
+
+func (t T) F() int { return t.int }
+
+type U struct { int int }
+
+func (u U) F() int { return u.int }
+
+type lint int
+
+type V struct { lint }
+
+func (v V) F() int { return int(v.lint) }
+
+type W struct { lint lint }
+
+func (w W) F() int { return int(w.lint) }
+
+
+
diff --git a/go/test/fixedbugs/issue3552.dir/two.go b/go/test/fixedbugs/issue3552.dir/two.go
new file mode 100644
index 0000000000000000000000000000000000000000..2f330bfdf3b4bbe43bb9f2284ebd03913861ac88
--- /dev/null
+++ b/go/test/fixedbugs/issue3552.dir/two.go
@@ -0,0 +1,22 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Use the functions in one.go so that the inlined
+// forms get type-checked.
+
+package two
+
+import "./one"
+
+func use() {
+ var t one.T
+ var u one.U
+ var v one.V
+ var w one.W
+
+ _ = t.F()
+ _ = u.F()
+ _ = v.F()
+ _ = w.F()
+}
diff --git a/go/test/fixedbugs/issue35586.dir/a.go b/go/test/fixedbugs/issue35586.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..f509b25473bfc9a7b324143f2d9e1983bda123ec
--- /dev/null
+++ b/go/test/fixedbugs/issue35586.dir/a.go
@@ -0,0 +1,9 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func D(_ string, _ int) (uint64, string) {
+ return 101, "bad"
+}
diff --git a/go/test/fixedbugs/issue35586.dir/b.go b/go/test/fixedbugs/issue35586.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..e0abb99fd41cb91d10666e9e663107e92435519b
--- /dev/null
+++ b/go/test/fixedbugs/issue35586.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func F(addr string) (uint64, string) {
+ return a.D(addr, 32)
+}
diff --git a/go/test/fixedbugs/issue35739.dir/a.go b/go/test/fixedbugs/issue35739.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..b79503e99615116d64831b2804df6e84c8aad85b
--- /dev/null
+++ b/go/test/fixedbugs/issue35739.dir/a.go
@@ -0,0 +1,15 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type myError string
+
+func (e myError) Error() string { return string(e) }
+
+const myErrorVal myError = "error"
+
+func IsMyError(err error) bool {
+ return err == error(myErrorVal)
+}
diff --git a/go/test/fixedbugs/issue35739.dir/b.go b/go/test/fixedbugs/issue35739.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..8d22aac8d6b058b186e04da35aa7ae1f259b70c8
--- /dev/null
+++ b/go/test/fixedbugs/issue35739.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func F(err error) bool {
+ return a.IsMyError(err)
+}
diff --git a/go/test/fixedbugs/issue36085.dir/a.go b/go/test/fixedbugs/issue36085.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..07cabcd2cceeaa299c1cc3729464e20544a9d849
--- /dev/null
+++ b/go/test/fixedbugs/issue36085.dir/a.go
@@ -0,0 +1,3 @@
+package a
+
+type W = map[int32]interface{}
diff --git a/go/test/fixedbugs/issue36085.dir/b.go b/go/test/fixedbugs/issue36085.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..0ebfe9fb6107d24e32c7c04d45df85c29901499c
--- /dev/null
+++ b/go/test/fixedbugs/issue36085.dir/b.go
@@ -0,0 +1,8 @@
+package main
+
+import "./a"
+
+var w a.W
+var X interface{} = &w
+
+func main() {}
diff --git a/go/test/fixedbugs/issue37513.dir/main.go b/go/test/fixedbugs/issue37513.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..75106521b6b9e995a624e4fbc2a831e325c5b849
--- /dev/null
+++ b/go/test/fixedbugs/issue37513.dir/main.go
@@ -0,0 +1,27 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "bytes"
+ "fmt"
+ "os"
+ "os/exec"
+)
+
+func main() {
+ if len(os.Args) > 1 {
+ // Generate a SIGILL.
+ sigill()
+ return
+ }
+ // Run ourselves with an extra argument. That process should SIGILL.
+ out, _ := exec.Command(os.Args[0], "foo").CombinedOutput()
+ want := "instruction bytes: 0xf 0xb 0xc3"
+ if !bytes.Contains(out, []byte(want)) {
+ fmt.Printf("got:\n%s\nwant:\n%s\n", string(out), want)
+ }
+}
+func sigill()
diff --git a/go/test/fixedbugs/issue37513.dir/sigill_amd64.s b/go/test/fixedbugs/issue37513.dir/sigill_amd64.s
new file mode 100644
index 0000000000000000000000000000000000000000..43260c21aed64afaf9c137bd1ae3ed23c15181ba
--- /dev/null
+++ b/go/test/fixedbugs/issue37513.dir/sigill_amd64.s
@@ -0,0 +1,7 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+TEXT ·sigill(SB),0,$0-0
+ UD2 // generates a SIGILL
+ RET
diff --git a/go/test/fixedbugs/issue37837.dir/a.go b/go/test/fixedbugs/issue37837.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..49d830ffbc7c66feae7b65904347d30e6607ea52
--- /dev/null
+++ b/go/test/fixedbugs/issue37837.dir/a.go
@@ -0,0 +1,33 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func F(i interface{}) int { // ERROR "can inline F" "i does not escape"
+ switch i.(type) {
+ case nil:
+ return 0
+ case int:
+ return 1
+ case float64:
+ return 2
+ default:
+ return 3
+ }
+}
+
+func G(i interface{}) interface{} { // ERROR "can inline G" "leaking param: i"
+ switch i := i.(type) {
+ case nil: // ERROR "moved to heap: i"
+ return &i
+ case int: // ERROR "moved to heap: i"
+ return &i
+ case float64: // ERROR "moved to heap: i"
+ return &i
+ case string, []byte: // ERROR "moved to heap: i"
+ return &i
+ default: // ERROR "moved to heap: i"
+ return &i
+ }
+}
diff --git a/go/test/fixedbugs/issue37837.dir/b.go b/go/test/fixedbugs/issue37837.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..461f5c7a553e8fdc6e8ee90ccd0ab357f79cab46
--- /dev/null
+++ b/go/test/fixedbugs/issue37837.dir/b.go
@@ -0,0 +1,32 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+func main() {
+ // Test that inlined type switches without short variable
+ // declarations work correctly.
+ check(0, a.F(nil)) // ERROR "inlining call to a.F"
+ check(1, a.F(0)) // ERROR "inlining call to a.F" "does not escape"
+ check(2, a.F(0.0)) // ERROR "inlining call to a.F" "does not escape"
+ check(3, a.F("")) // ERROR "inlining call to a.F" "does not escape"
+
+ // Test that inlined type switches with short variable
+ // declarations work correctly.
+ _ = a.G(nil).(*interface{}) // ERROR "inlining call to a.G"
+ _ = a.G(1).(*int) // ERROR "inlining call to a.G" "does not escape"
+ _ = a.G(2.0).(*float64) // ERROR "inlining call to a.G" "does not escape"
+ _ = (*a.G("").(*interface{})).(string) // ERROR "inlining call to a.G" "does not escape"
+ _ = (*a.G(([]byte)(nil)).(*interface{})).([]byte) // ERROR "inlining call to a.G" "does not escape"
+ _ = (*a.G(true).(*interface{})).(bool) // ERROR "inlining call to a.G" "does not escape"
+}
+
+//go:noinline
+func check(want, got int) {
+ if want != got {
+ println("want", want, "but got", got)
+ }
+}
diff --git a/go/test/fixedbugs/issue40252.dir/a.go b/go/test/fixedbugs/issue40252.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..5519e9331aa0c6103444bfe8f30d03df07e5a134
--- /dev/null
+++ b/go/test/fixedbugs/issue40252.dir/a.go
@@ -0,0 +1,14 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type I interface {
+ Func()
+}
+
+func Call() {
+ f := I.Func
+ f(nil)
+}
diff --git a/go/test/fixedbugs/issue40252.dir/main.go b/go/test/fixedbugs/issue40252.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..93f5b706242ef723f7362d7eea2b9913ba6d25b6
--- /dev/null
+++ b/go/test/fixedbugs/issue40252.dir/main.go
@@ -0,0 +1,16 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+func main() {
+ defer func() {
+ if recover() == nil {
+ panic("expected nil pointer dereference")
+ }
+ }()
+ a.Call()
+}
diff --git a/go/test/fixedbugs/issue42284.dir/a.go b/go/test/fixedbugs/issue42284.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..e55f190d7ee5710732a04f2597915b6cb887ed11
--- /dev/null
+++ b/go/test/fixedbugs/issue42284.dir/a.go
@@ -0,0 +1,29 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type I interface{ M() }
+type T int
+
+func (T) M() {} // ERROR "can inline T.M"
+
+func E() I { // ERROR "can inline E"
+ return T(0) // ERROR "T\(0\) escapes to heap"
+}
+
+func F(i I) I { // ERROR "can inline F" "leaking param: i to result ~r0 level=0"
+ i = nil
+ return i
+}
+
+func g() {
+ h := E() // ERROR "inlining call to E" "T\(0\) does not escape"
+ h.M() // ERROR "devirtualizing h.M to T" "inlining call to T.M"
+
+ i := F(T(0)) // ERROR "inlining call to F" "T\(0\) does not escape"
+
+ // It is fine that we devirtualize here, as we add an additional nilcheck.
+ i.M() // ERROR "devirtualizing i.M to T" "inlining call to T.M"
+}
diff --git a/go/test/fixedbugs/issue42284.dir/b.go b/go/test/fixedbugs/issue42284.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..4a0b7cea102e8801eb36ce76ea08b4ed35b61ffb
--- /dev/null
+++ b/go/test/fixedbugs/issue42284.dir/b.go
@@ -0,0 +1,17 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func g() {
+ h := a.E() // ERROR "inlining call to a.E" "T\(0\) does not escape"
+ h.M() // ERROR "devirtualizing h.M to a.T" "inlining call to a.T.M"
+
+ i := a.F(a.T(0)) // ERROR "inlining call to a.F" "a.T\(0\) does not escape"
+
+ // It is fine that we devirtualize here, as we add an additional nilcheck.
+ i.M() // ERROR "devirtualizing i.M to a.T" "inlining call to a.T.M"
+}
diff --git a/go/test/fixedbugs/issue42401.dir/a.go b/go/test/fixedbugs/issue42401.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..75f8e7f91fc35f6efb964a00874d3216489c8068
--- /dev/null
+++ b/go/test/fixedbugs/issue42401.dir/a.go
@@ -0,0 +1,11 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+var s string
+
+func init() { s = "a" }
+
+func Get() string { return s }
diff --git a/go/test/fixedbugs/issue42401.dir/b.go b/go/test/fixedbugs/issue42401.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..fc675d82301881e94934c3b72f47ede071844f57
--- /dev/null
+++ b/go/test/fixedbugs/issue42401.dir/b.go
@@ -0,0 +1,25 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ _ "unsafe"
+
+ "./a"
+)
+
+//go:linkname s test/a.s
+var s string
+
+func main() {
+ if a.Get() != "a" {
+ panic("FAIL")
+ }
+
+ s = "b"
+ if a.Get() != "b" {
+ panic("FAIL")
+ }
+}
diff --git a/go/test/fixedbugs/issue4252.dir/a.go b/go/test/fixedbugs/issue4252.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..a587e28da7959a79a7da2333873548e916b5de7e
--- /dev/null
+++ b/go/test/fixedbugs/issue4252.dir/a.go
@@ -0,0 +1,35 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// A package that redeclares common builtin names.
+package a
+
+var true = 0 == 1
+var false = 0 == 0
+var nil = 1
+
+const append = 42
+
+type error bool
+type int interface{}
+
+func len(interface{}) int32 { return 42 }
+
+func Test() {
+ var array [append]int
+ if true {
+ panic("unexpected builtin true instead of redeclared one")
+ }
+ if !false {
+ panic("unexpected builtin false instead of redeclared one")
+ }
+ if len(array) != 42 {
+ println(len(array))
+ panic("unexpected call of builtin len")
+ }
+}
+
+func InlinedFakeTrue() error { return error(true) }
+func InlinedFakeFalse() error { return error(false) }
+func InlinedFakeNil() int { return nil }
diff --git a/go/test/fixedbugs/issue4252.dir/main.go b/go/test/fixedbugs/issue4252.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..02d9836e98da207fc2e35bdbed3658193fd6ef9d
--- /dev/null
+++ b/go/test/fixedbugs/issue4252.dir/main.go
@@ -0,0 +1,20 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+func main() {
+ if a.InlinedFakeTrue() {
+ panic("returned true was the real one")
+ }
+ if !a.InlinedFakeFalse() {
+ panic("returned false was the real one")
+ }
+ if a.InlinedFakeNil() == nil {
+ panic("returned nil was the real one")
+ }
+ a.Test()
+}
diff --git a/go/test/fixedbugs/issue43164.dir/a.go b/go/test/fixedbugs/issue43164.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..fa10e85061225433bd28ca229be1bd50924cfd85
--- /dev/null
+++ b/go/test/fixedbugs/issue43164.dir/a.go
@@ -0,0 +1,13 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+import . "strings"
+
+var _ = Index // use strings
+
+type t struct{ Index int }
+
+var _ = t{Index: 0}
diff --git a/go/test/fixedbugs/issue43164.dir/b.go b/go/test/fixedbugs/issue43164.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..b025927a059a8eb39e9f53ef1314d1e93b9f623d
--- /dev/null
+++ b/go/test/fixedbugs/issue43164.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+import . "bytes"
+
+var _ = Index // use bytes
+
+var _ = t{Index: 0}
diff --git a/go/test/fixedbugs/issue4326.dir/p1.go b/go/test/fixedbugs/issue4326.dir/p1.go
new file mode 100644
index 0000000000000000000000000000000000000000..ab214befb4b82845b816c657e0581b416e0cb931
--- /dev/null
+++ b/go/test/fixedbugs/issue4326.dir/p1.go
@@ -0,0 +1,12 @@
+package p1
+
+type O map[string]map[string]string
+
+func (opts O) RemoveOption(sect, opt string) bool {
+ if _, ok := opts[sect]; !ok {
+ return false
+ }
+ _, ok := opts[sect][opt]
+ delete(opts[sect], opt)
+ return ok
+}
diff --git a/go/test/fixedbugs/issue4326.dir/p2.go b/go/test/fixedbugs/issue4326.dir/p2.go
new file mode 100644
index 0000000000000000000000000000000000000000..8e86266dd8d4adb2f8aec9218b26c7595cfcabec
--- /dev/null
+++ b/go/test/fixedbugs/issue4326.dir/p2.go
@@ -0,0 +1,5 @@
+package p2
+
+import "./p1"
+
+func NewO() p1.O { return nil }
diff --git a/go/test/fixedbugs/issue4326.dir/q1.go b/go/test/fixedbugs/issue4326.dir/q1.go
new file mode 100644
index 0000000000000000000000000000000000000000..f118eb09252a48c51942b1f602d637620afd1a12
--- /dev/null
+++ b/go/test/fixedbugs/issue4326.dir/q1.go
@@ -0,0 +1,8 @@
+package q1
+
+func Deref(typ interface{}) interface{} {
+ if typ, ok := typ.(*int); ok {
+ return *typ
+ }
+ return typ
+}
diff --git a/go/test/fixedbugs/issue4326.dir/q2.go b/go/test/fixedbugs/issue4326.dir/q2.go
new file mode 100644
index 0000000000000000000000000000000000000000..075e2b21e7a438ca7a7eccfedf1ad06e0275c1d8
--- /dev/null
+++ b/go/test/fixedbugs/issue4326.dir/q2.go
@@ -0,0 +1,11 @@
+package main
+
+import "./q1"
+
+func main() {
+ x := 1
+ y := q1.Deref(&x)
+ if y != 1 {
+ panic("y != 1")
+ }
+}
diff --git a/go/test/fixedbugs/issue4326.dir/z.go b/go/test/fixedbugs/issue4326.dir/z.go
new file mode 100644
index 0000000000000000000000000000000000000000..9b222e8b40276754272f39fadaf75b0f0d30d77b
--- /dev/null
+++ b/go/test/fixedbugs/issue4326.dir/z.go
@@ -0,0 +1,7 @@
+package z
+
+import "./p2"
+
+func main() {
+ p2.NewO().RemoveOption("hello", "world")
+}
diff --git a/go/test/fixedbugs/issue43479.dir/a.go b/go/test/fixedbugs/issue43479.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..ed3e6a5d9b67ee317f5c52352599c787983c274f
--- /dev/null
+++ b/go/test/fixedbugs/issue43479.dir/a.go
@@ -0,0 +1,27 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type Here struct{ stuff int }
+type Info struct{ Dir string }
+
+func New() Here { return Here{} }
+func (h Here) Dir(p string) (Info, error)
+
+type I interface{ M(x string) }
+
+type T = struct {
+ Here
+ I
+}
+
+var X T
+
+var A = (*T).Dir
+var B = T.Dir
+var C = X.Dir
+var D = (*T).M
+var E = T.M
+var F = X.M
diff --git a/go/test/fixedbugs/issue43479.dir/b.go b/go/test/fixedbugs/issue43479.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..02d16909cc527cc8f166d2b0086b16804553ef52
--- /dev/null
+++ b/go/test/fixedbugs/issue43479.dir/b.go
@@ -0,0 +1,38 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+var Here = a.New()
+var Dir = Here.Dir
+
+type T = struct {
+ a.Here
+ a.I
+}
+
+var X T
+
+// Test exporting the type of method values for anonymous structs with
+// promoted methods.
+var A = a.A
+var B = a.B
+var C = a.C
+var D = a.D
+var E = a.E
+var F = a.F
+var G = (*a.T).Dir
+var H = a.T.Dir
+var I = a.X.Dir
+var J = (*a.T).M
+var K = a.T.M
+var L = a.X.M
+var M = (*T).Dir
+var N = T.Dir
+var O = X.Dir
+var P = (*T).M
+var Q = T.M
+var R = X.M
diff --git a/go/test/fixedbugs/issue43551.dir/a.go b/go/test/fixedbugs/issue43551.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..d890dd0c651caa1cdecd073de50512fd09b72575
--- /dev/null
+++ b/go/test/fixedbugs/issue43551.dir/a.go
@@ -0,0 +1,13 @@
+package a
+
+type S struct {
+ a Key
+}
+
+func (s S) A() Key {
+ return s.a
+}
+
+type Key struct {
+ key int64
+}
diff --git a/go/test/fixedbugs/issue43551.dir/b.go b/go/test/fixedbugs/issue43551.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..ba062bf14cf12b9d613c224ea4cb636f6c7196d8
--- /dev/null
+++ b/go/test/fixedbugs/issue43551.dir/b.go
@@ -0,0 +1,14 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+type S a.S
+type Key a.Key
+
+func (s S) A() Key {
+ return Key(a.S(s).A())
+}
diff --git a/go/test/fixedbugs/issue43633.dir/a.go b/go/test/fixedbugs/issue43633.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..946a37e87ef1a64d31943293e1d41f8e9b550f36
--- /dev/null
+++ b/go/test/fixedbugs/issue43633.dir/a.go
@@ -0,0 +1,28 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func F() bool {
+ {
+ x := false
+ _ = x
+ }
+ if false {
+ _ = func(x bool) {}
+ }
+ x := true
+ return x
+}
+
+func G() func() bool {
+ x := true
+ return func() bool {
+ {
+ x := false
+ _ = x
+ }
+ return x
+ }
+}
diff --git a/go/test/fixedbugs/issue43633.dir/main.go b/go/test/fixedbugs/issue43633.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..320e00013c3130e69fb271e859cc9cbb37e93dad
--- /dev/null
+++ b/go/test/fixedbugs/issue43633.dir/main.go
@@ -0,0 +1,18 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+var g = a.G()
+
+func main() {
+ if !a.F() {
+ panic("FAIL")
+ }
+ if !g() {
+ panic("FAIL")
+ }
+}
diff --git a/go/test/fixedbugs/issue4370.dir/p1.go b/go/test/fixedbugs/issue4370.dir/p1.go
new file mode 100644
index 0000000000000000000000000000000000000000..d010e936534aebef4434f3e6a5393a1a97af4b7e
--- /dev/null
+++ b/go/test/fixedbugs/issue4370.dir/p1.go
@@ -0,0 +1,20 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p1
+
+type Magic int
+
+type T struct {
+ x interface{}
+}
+
+func (t *T) M() bool {
+ _, ok := t.x.(Magic)
+ return ok
+}
+
+func F(t *T) {
+ println(t)
+}
diff --git a/go/test/fixedbugs/issue4370.dir/p2.go b/go/test/fixedbugs/issue4370.dir/p2.go
new file mode 100644
index 0000000000000000000000000000000000000000..0d3e23625ec245a215f87594218925f25fcb8f19
--- /dev/null
+++ b/go/test/fixedbugs/issue4370.dir/p2.go
@@ -0,0 +1,16 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p2
+
+import "./p1"
+
+type T struct {
+ p1.T
+}
+
+func F() {
+ var t T
+ p1.F(&t.T)
+}
diff --git a/go/test/fixedbugs/issue4370.dir/p3.go b/go/test/fixedbugs/issue4370.dir/p3.go
new file mode 100644
index 0000000000000000000000000000000000000000..c275c6e222dd8b1b3f161b8898fcbcbec90abf98
--- /dev/null
+++ b/go/test/fixedbugs/issue4370.dir/p3.go
@@ -0,0 +1,13 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p3
+
+import "./p2"
+
+func F() {
+ p2.F()
+ var t p2.T
+ println(t.T.M())
+}
diff --git a/go/test/fixedbugs/issue43962.dir/a.go b/go/test/fixedbugs/issue43962.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..168b2063b4872373b43dfbc27e30757fc7af25d2
--- /dev/null
+++ b/go/test/fixedbugs/issue43962.dir/a.go
@@ -0,0 +1,5 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package init
diff --git a/go/test/fixedbugs/issue43962.dir/b.go b/go/test/fixedbugs/issue43962.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..f55fea11c19347c42645532e7bc6e7afddd87b4d
--- /dev/null
+++ b/go/test/fixedbugs/issue43962.dir/b.go
@@ -0,0 +1,7 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a" // ERROR "cannot import package as init"
diff --git a/go/test/fixedbugs/issue44325.dir/a.go b/go/test/fixedbugs/issue44325.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..5a22b455b7ea8559ce4a8ab737c1b8b3707a3ad3
--- /dev/null
+++ b/go/test/fixedbugs/issue44325.dir/a.go
@@ -0,0 +1,13 @@
+// Copyright 2021 The Go Authors. All rights reserved. Use of this
+// source code is governed by a BSD-style license that can be found in
+// the LICENSE file.
+
+package a
+
+func FM() func() {
+ return func() {
+ _ = func() int {
+ return 0
+ }
+ }
+}
diff --git a/go/test/fixedbugs/issue44325.dir/b.go b/go/test/fixedbugs/issue44325.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..c4d77e311a9a6e3bd7fcffbf296191264152e08d
--- /dev/null
+++ b/go/test/fixedbugs/issue44325.dir/b.go
@@ -0,0 +1,13 @@
+// Copyright 2021 The Go Authors. All rights reserved. Use of this
+// source code is governed by a BSD-style license that can be found in
+// the LICENSE file.
+
+package b
+
+import (
+ "./a"
+)
+
+func F() {
+ a.FM()
+}
diff --git a/go/test/fixedbugs/issue44330.dir/a.go b/go/test/fixedbugs/issue44330.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..9d3ab9fe80e0870a85984ddd7db74176c8fded8c
--- /dev/null
+++ b/go/test/fixedbugs/issue44330.dir/a.go
@@ -0,0 +1,21 @@
+// Copyright 2021 The Go Authors. All rights reserved. Use of this
+// source code is governed by a BSD-style license that can be found in
+// the LICENSE file.
+
+package a
+
+type Table struct {
+ ColumnSeparator bool
+ RowSeparator bool
+
+ // ColumnResizer is called on each Draw. Can be used for custom column sizing.
+ ColumnResizer func()
+}
+
+func NewTable() *Table {
+ return &Table{
+ ColumnSeparator: true,
+ RowSeparator: true,
+ ColumnResizer: func() {},
+ }
+}
diff --git a/go/test/fixedbugs/issue44330.dir/b.go b/go/test/fixedbugs/issue44330.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..1d5742421bdf9f78909e7f279229d7906afb237f
--- /dev/null
+++ b/go/test/fixedbugs/issue44330.dir/b.go
@@ -0,0 +1,23 @@
+// Copyright 2021 The Go Authors. All rights reserved. Use of this
+// source code is governed by a BSD-style license that can be found in
+// the LICENSE file.
+
+package main
+
+import (
+ "./a"
+)
+
+type Term struct {
+ top *a.Table
+}
+
+//go:noinline
+func NewFred() *Term {
+ table := a.NewTable()
+ return &Term{top: table}
+}
+
+func main() {
+ NewFred()
+}
diff --git a/go/test/fixedbugs/issue44335.dir/a.go b/go/test/fixedbugs/issue44335.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..2c9c2178135114fb9ef136359fe9e3bfd27b75d2
--- /dev/null
+++ b/go/test/fixedbugs/issue44335.dir/a.go
@@ -0,0 +1,17 @@
+// Copyright 2021 The Go Authors. All rights reserved. Use of this
+// source code is governed by a BSD-style license that can be found in
+// the LICENSE file
+
+package a
+
+type W struct {
+ M func(string) string
+}
+
+func FM(m string) func(W) {
+ return func(pw W) {
+ pw.M = func(string) string {
+ return m
+ }
+ }
+}
diff --git a/go/test/fixedbugs/issue44335.dir/b.go b/go/test/fixedbugs/issue44335.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..e72c2abc6a546b4b104e11cde25e8f06d4384df3
--- /dev/null
+++ b/go/test/fixedbugs/issue44335.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2021 The Go Authors. All rights reserved. Use of this
+// source code is governed by a BSD-style license that can be found in
+// the LICENSE file.
+
+package b
+
+import "./a"
+
+func F() {
+ a.FM("")
+}
diff --git a/go/test/fixedbugs/issue44355.dir/a.go b/go/test/fixedbugs/issue44355.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..0f63c6fd983862d6409462cf1ecf23cae9f8f906
--- /dev/null
+++ b/go/test/fixedbugs/issue44355.dir/a.go
@@ -0,0 +1,7 @@
+// Copyright 2021 The Go Authors. All rights reserved. Use of this
+// source code is governed by a BSD-style license that can be found in
+// the LICENSE file.
+
+package a
+
+func F() (_ *int) { return nil }
diff --git a/go/test/fixedbugs/issue44355.dir/b.go b/go/test/fixedbugs/issue44355.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..09d5bde887a56773bc8d45645ee800232411f66b
--- /dev/null
+++ b/go/test/fixedbugs/issue44355.dir/b.go
@@ -0,0 +1,9 @@
+// Copyright 2021 The Go Authors. All rights reserved. Use of this
+// source code is governed by a BSD-style license that can be found in
+// the LICENSE file.
+
+package b
+
+import "./a"
+
+var _ = a.F()
diff --git a/go/test/fixedbugs/issue44370.dir/a.go b/go/test/fixedbugs/issue44370.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..c5bf1bcbc72e77975720a44b70e30d71f673dc42
--- /dev/null
+++ b/go/test/fixedbugs/issue44370.dir/a.go
@@ -0,0 +1,20 @@
+// Copyright 2021 The Go Authors. All rights reserved. Use of this
+// source code is governed by a BSD-style license that can be found in
+// the LICENSE file.
+
+package a
+
+// A StoppableWaitGroup waits for a collection of goroutines to finish.
+type StoppableWaitGroup struct {
+ // i is the internal counter which can store tolerate negative values
+ // as opposed the golang's library WaitGroup.
+ i *int64
+}
+
+// NewStoppableWaitGroup returns a new StoppableWaitGroup. When the 'Stop' is
+// executed, following 'Add()' calls won't have any effect.
+func NewStoppableWaitGroup() *StoppableWaitGroup {
+ return &StoppableWaitGroup{
+ i: func() *int64 { i := int64(0); return &i }(),
+ }
+}
diff --git a/go/test/fixedbugs/issue44370.dir/b.go b/go/test/fixedbugs/issue44370.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..f0e0b4e55fd89cfa5c53aaf1a4e84c7e05272ed7
--- /dev/null
+++ b/go/test/fixedbugs/issue44370.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2021 The Go Authors. All rights reserved. Use of this
+// source code is governed by a BSD-style license that can be found in
+// the LICENSE file.
+
+package b
+
+import "./a"
+
+func JoinClusterServices() {
+ _ = a.NewStoppableWaitGroup()
+}
diff --git a/go/test/fixedbugs/issue44732.dir/bar/bar.go b/go/test/fixedbugs/issue44732.dir/bar/bar.go
new file mode 100644
index 0000000000000000000000000000000000000000..fc141616100e09767db3604d18dc82ba24d8370c
--- /dev/null
+++ b/go/test/fixedbugs/issue44732.dir/bar/bar.go
@@ -0,0 +1,11 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bar
+
+import "issue44732.dir/foo"
+
+type Bar struct {
+ Foo *foo.Foo
+}
diff --git a/go/test/fixedbugs/issue44732.dir/foo/foo.go b/go/test/fixedbugs/issue44732.dir/foo/foo.go
new file mode 100644
index 0000000000000000000000000000000000000000..c8afb0e880e5b467ee42d25232f6d8488f9b78e2
--- /dev/null
+++ b/go/test/fixedbugs/issue44732.dir/foo/foo.go
@@ -0,0 +1,13 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package foo
+
+type Foo struct {
+ updatecb func()
+}
+
+func NewFoo() *Foo {
+ return &Foo{updatecb: nil}
+}
diff --git a/go/test/fixedbugs/issue44732.dir/main.go b/go/test/fixedbugs/issue44732.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..21208ecdd93d888284f0470fbc7cd9ad6b45c2e9
--- /dev/null
+++ b/go/test/fixedbugs/issue44732.dir/main.go
@@ -0,0 +1,15 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "issue44732.dir/bar"
+ "issue44732.dir/foo"
+)
+
+func main() {
+ _ = bar.Bar{}
+ _ = foo.NewFoo()
+}
diff --git a/go/test/fixedbugs/issue4510.dir/f1.go b/go/test/fixedbugs/issue4510.dir/f1.go
new file mode 100644
index 0000000000000000000000000000000000000000..1217106fca4db57046225ec3b0e982a74460c656
--- /dev/null
+++ b/go/test/fixedbugs/issue4510.dir/f1.go
@@ -0,0 +1,9 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+import "fmt" // GCCGO_ERROR "fmt redeclared|imported"
+
+var _ = fmt.Printf
diff --git a/go/test/fixedbugs/issue4510.dir/f2.go b/go/test/fixedbugs/issue4510.dir/f2.go
new file mode 100644
index 0000000000000000000000000000000000000000..1a67153771fa64fc8d11c54ed66999a0d7c65853
--- /dev/null
+++ b/go/test/fixedbugs/issue4510.dir/f2.go
@@ -0,0 +1,7 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+func fmt() {} // GC_ERROR "fmt already declared through import of package"
diff --git a/go/test/fixedbugs/issue45503.dir/a.go b/go/test/fixedbugs/issue45503.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..b45835bd85f60adf5406824655145f601e4a26e2
--- /dev/null
+++ b/go/test/fixedbugs/issue45503.dir/a.go
@@ -0,0 +1,15 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type S struct{}
+
+func (s *S) M() {
+ s.m((*S).N)
+}
+
+func (s *S) N() {}
+
+func (s *S) m(func(*S)) {}
diff --git a/go/test/fixedbugs/issue45503.dir/b.go b/go/test/fixedbugs/issue45503.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..530c394eaf9d73225aae163a6bf7294e67d8cbb7
--- /dev/null
+++ b/go/test/fixedbugs/issue45503.dir/b.go
@@ -0,0 +1,12 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func F() {
+ s := a.S{}
+ s.M()
+}
diff --git a/go/test/fixedbugs/issue4590.dir/pkg1.go b/go/test/fixedbugs/issue4590.dir/pkg1.go
new file mode 100644
index 0000000000000000000000000000000000000000..96cac0a5c1c0d8851ff2a73629bca222d2ea482a
--- /dev/null
+++ b/go/test/fixedbugs/issue4590.dir/pkg1.go
@@ -0,0 +1,26 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package pkg1
+
+type A interface {
+ Write() error
+}
+
+type B interface {
+ Hello()
+ world()
+}
+
+type C struct{}
+
+func (c C) Write() error { return nil }
+
+var T = struct{ A }{nil}
+var U = struct{ B }{nil}
+var V A = struct{ *C }{nil}
+var W = interface {
+ Write() error
+ Hello()
+}(nil)
diff --git a/go/test/fixedbugs/issue4590.dir/pkg2.go b/go/test/fixedbugs/issue4590.dir/pkg2.go
new file mode 100644
index 0000000000000000000000000000000000000000..98bc2a52fb96da1c2ad93177d86e50cd2681d323
--- /dev/null
+++ b/go/test/fixedbugs/issue4590.dir/pkg2.go
@@ -0,0 +1,15 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package pkg2
+
+import "./pkg1"
+
+var T = struct{ pkg1.A }{nil}
+var U = struct{ pkg1.B }{nil}
+var V pkg1.A = struct{ *pkg1.C }{nil}
+var W = interface {
+ Write() error
+ Hello()
+}(nil)
diff --git a/go/test/fixedbugs/issue4590.dir/prog.go b/go/test/fixedbugs/issue4590.dir/prog.go
new file mode 100644
index 0000000000000000000000000000000000000000..32055b28e246add2113231eff5df77f9a8ade611
--- /dev/null
+++ b/go/test/fixedbugs/issue4590.dir/prog.go
@@ -0,0 +1,25 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./pkg1"
+ "./pkg2"
+)
+
+func main() {
+ if pkg1.T != pkg2.T {
+ panic("pkg1.T != pkg2.T")
+ }
+ if pkg1.U != pkg2.U {
+ panic("pkg1.U != pkg2.U")
+ }
+ if pkg1.V != pkg2.V {
+ panic("pkg1.V != pkg2.V")
+ }
+ if pkg1.W != pkg2.W {
+ panic("pkg1.W != pkg2.W")
+ }
+}
diff --git a/go/test/fixedbugs/issue46653.dir/bad/bad.go b/go/test/fixedbugs/issue46653.dir/bad/bad.go
new file mode 100644
index 0000000000000000000000000000000000000000..c1611b8347a3247deeb7f722920cf9e9e4049e7d
--- /dev/null
+++ b/go/test/fixedbugs/issue46653.dir/bad/bad.go
@@ -0,0 +1,64 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func Bad() {
+ m := make(map[int64]A)
+ a := m[0]
+ if len(a.B.C1.D2.E2.F1) != 0 ||
+ len(a.B.C1.D2.E2.F2) != 0 ||
+ len(a.B.C1.D2.E2.F3) != 0 ||
+ len(a.B.C1.D2.E2.F4) != 0 ||
+ len(a.B.C1.D2.E2.F5) != 0 ||
+ len(a.B.C1.D2.E2.F6) != 0 ||
+ len(a.B.C1.D2.E2.F7) != 0 ||
+ len(a.B.C1.D2.E2.F8) != 0 ||
+ len(a.B.C1.D2.E2.F9) != 0 ||
+ len(a.B.C1.D2.E2.F10) != 0 ||
+ len(a.B.C1.D2.E2.F11) != 0 ||
+ len(a.B.C1.D2.E2.F16) != 0 {
+ panic("bad")
+ }
+}
+
+type A struct {
+ B
+}
+
+type B struct {
+ C1 C
+ C2 C
+}
+
+type C struct {
+ D1 D
+ D2 D
+}
+
+type D struct {
+ E1 E
+ E2 E
+ E3 E
+ E4 E
+}
+
+type E struct {
+ F1 string
+ F2 string
+ F3 string
+ F4 string
+ F5 string
+ F6 string
+ F7 string
+ F8 string
+ F9 string
+ F10 string
+ F11 string
+ F12 string
+ F13 string
+ F14 string
+ F15 string
+ F16 string
+}
diff --git a/go/test/fixedbugs/issue46653.dir/main.go b/go/test/fixedbugs/issue46653.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..e2a96e54ec59949c82935946284613ffa62b669a
--- /dev/null
+++ b/go/test/fixedbugs/issue46653.dir/main.go
@@ -0,0 +1,27 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ bad "issue46653.dir/bad"
+)
+
+func main() {
+ bad.Bad()
+}
+
+func neverCalled() L {
+ m := make(map[string]L)
+ return m[""]
+}
+
+type L struct {
+ A Data
+ B Data
+}
+
+type Data struct {
+ F1 [22][]string
+}
diff --git a/go/test/fixedbugs/issue47068.dir/a.go b/go/test/fixedbugs/issue47068.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..30a51c1edb24d10f163675426862f67060d6eb31
--- /dev/null
+++ b/go/test/fixedbugs/issue47068.dir/a.go
@@ -0,0 +1,15 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func A() {
+ var m map[int]int = map[int]int{
+ 0: 0, 1: 0, 2: 0, 3: 0, 4: 0, 5: 0, 6: 0, 7: 0, 8: 0, 9: 0,
+ 10: 0, 11: 0, 12: 0, 13: 0, 14: 0, 15: 0, 16: 0, 17: 0, 18: 0, 19: 0,
+ 20: 0, 21: 0, 22: 0, 23: 0, 24: 0, 25: 0, 26: 0, 27: 0, 28: 0, 29: 0}
+ if len(m) != 30 {
+ panic("unexpected map length")
+ }
+}
diff --git a/go/test/fixedbugs/issue47068.dir/b.go b/go/test/fixedbugs/issue47068.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..d341a4a395005cb9b5411ece09004ee9c2571118
--- /dev/null
+++ b/go/test/fixedbugs/issue47068.dir/b.go
@@ -0,0 +1,15 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "reflect"
+
+func B() {
+ t1 := reflect.TypeOf([30]int{})
+ t2 := reflect.TypeOf(new([30]int)).Elem()
+ if t1 != t2 {
+ panic("[30]int types do not match")
+ }
+}
diff --git a/go/test/fixedbugs/issue47068.dir/main.go b/go/test/fixedbugs/issue47068.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..411e7db10382dcd6b3afe57b815269edf51a0e3b
--- /dev/null
+++ b/go/test/fixedbugs/issue47068.dir/main.go
@@ -0,0 +1,15 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./a"
+ "./b"
+)
+
+func main() {
+ a.A()
+ b.B()
+}
diff --git a/go/test/fixedbugs/issue47087.dir/a.go b/go/test/fixedbugs/issue47087.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..6093092aceea7a3838ba9846cf2a65cc60db9d38
--- /dev/null
+++ b/go/test/fixedbugs/issue47087.dir/a.go
@@ -0,0 +1,9 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func F() interface{} { return struct{ _ []int }{} }
+
+var X = F()
diff --git a/go/test/fixedbugs/issue47087.dir/b.go b/go/test/fixedbugs/issue47087.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..8f96d25a12bf2c26cca35cb036a482fb05f615ff
--- /dev/null
+++ b/go/test/fixedbugs/issue47087.dir/b.go
@@ -0,0 +1,9 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+func F() interface{} { return struct{ _ []int }{} }
+
+var X = F()
diff --git a/go/test/fixedbugs/issue47087.dir/main.go b/go/test/fixedbugs/issue47087.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..16c1cc616d09bb16cf566621c71c8586c59f64e2
--- /dev/null
+++ b/go/test/fixedbugs/issue47087.dir/main.go
@@ -0,0 +1,19 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./a"
+ "./b"
+)
+
+func main() {
+ if a.F() == b.F() {
+ panic("FAIL")
+ }
+ if a.X == b.X {
+ panic("FAIL")
+ }
+}
diff --git a/go/test/fixedbugs/issue47131.dir/a.go b/go/test/fixedbugs/issue47131.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..6e798d1d0c8e2dd7370416750e2fc5764346a9e9
--- /dev/null
+++ b/go/test/fixedbugs/issue47131.dir/a.go
@@ -0,0 +1,13 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type MyInt int
+
+type MyIntAlias = MyInt
+
+func (mia *MyIntAlias) Get() int {
+ return int(*mia)
+}
diff --git a/go/test/fixedbugs/issue47131.dir/b.go b/go/test/fixedbugs/issue47131.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..c658127ca9d53c2495f12690437e095401f9a4c2
--- /dev/null
+++ b/go/test/fixedbugs/issue47131.dir/b.go
@@ -0,0 +1,12 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func F2() int {
+ var mia a.MyIntAlias
+ return mia.Get()
+}
diff --git a/go/test/fixedbugs/issue47185.dir/bad/bad.go b/go/test/fixedbugs/issue47185.dir/bad/bad.go
new file mode 100644
index 0000000000000000000000000000000000000000..1aa4fbb909522ae1409f0895e3f04c58a47d73ee
--- /dev/null
+++ b/go/test/fixedbugs/issue47185.dir/bad/bad.go
@@ -0,0 +1,72 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+// Note that the use of CGO here is solely to trigger external
+// linking, since that is required to trigger that bad behavior
+// in this bug.
+
+// #include
+import "C"
+
+func Bad() {
+ m := make(map[int64]A)
+ a := m[0]
+ if len(a.B.C1.D2.E2.F1) != 0 ||
+ len(a.B.C1.D2.E2.F2) != 0 ||
+ len(a.B.C1.D2.E2.F3) != 0 ||
+ len(a.B.C1.D2.E2.F4) != 0 ||
+ len(a.B.C1.D2.E2.F5) != 0 ||
+ len(a.B.C1.D2.E2.F6) != 0 ||
+ len(a.B.C1.D2.E2.F7) != 0 ||
+ len(a.B.C1.D2.E2.F8) != 0 ||
+ len(a.B.C1.D2.E2.F9) != 0 ||
+ len(a.B.C1.D2.E2.F10) != 0 ||
+ len(a.B.C1.D2.E2.F11) != 0 ||
+ len(a.B.C1.D2.E2.F16) != 0 {
+ panic("bad")
+ }
+ C.malloc(100)
+}
+
+type A struct {
+ B
+}
+
+type B struct {
+ C1 C
+ C2 C
+}
+
+type C struct {
+ D1 D
+ D2 D
+}
+
+type D struct {
+ E1 E
+ E2 E
+ E3 E
+ E4 E
+}
+
+type E struct {
+ F1 string
+ F2 string
+ F3 string
+ F4 string
+ F5 string
+ F6 string
+ F7 string
+ F8 string
+ F9 string
+ F10 string
+ F11 string
+ F12 string
+ F13 string
+ F14 string
+ F15 string
+ F16 string
+}
diff --git a/go/test/fixedbugs/issue47185.dir/main.go b/go/test/fixedbugs/issue47185.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..7b46e55d8b566349cf5a9315bbd19dcd84f5bee7
--- /dev/null
+++ b/go/test/fixedbugs/issue47185.dir/main.go
@@ -0,0 +1,28 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ bad "issue47185.dir/bad"
+)
+
+func main() {
+ another()
+ bad.Bad()
+}
+
+func another() L {
+ m := make(map[string]L)
+ return m[""]
+}
+
+type L struct {
+ A Data
+ B Data
+}
+
+type Data struct {
+ F1 [22][]string
+}
diff --git a/go/test/fixedbugs/issue47201.dir/a.go b/go/test/fixedbugs/issue47201.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..54b70790926cd3a2e80747c5fa6607465b3035c0
--- /dev/null
+++ b/go/test/fixedbugs/issue47201.dir/a.go
@@ -0,0 +1,13 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ . "fmt"
+)
+
+func test() {
+ Println("foo")
+}
diff --git a/go/test/fixedbugs/issue47201.dir/b.go b/go/test/fixedbugs/issue47201.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..ae3ff3f2b8143d280da4958a17a5a21852ffb978
--- /dev/null
+++ b/go/test/fixedbugs/issue47201.dir/b.go
@@ -0,0 +1,9 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+func Println() {} // ERROR "Println redeclared in this block|Println already declared"
+
+func main() {}
diff --git a/go/test/fixedbugs/issue47317.dir/a.s b/go/test/fixedbugs/issue47317.dir/a.s
new file mode 100644
index 0000000000000000000000000000000000000000..b969ddb972c1d637b46992b2a77e72ffe1b807e9
--- /dev/null
+++ b/go/test/fixedbugs/issue47317.dir/a.s
@@ -0,0 +1,6 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+TEXT ·G(SB),4,$0
+ RET
diff --git a/go/test/fixedbugs/issue47317.dir/x.go b/go/test/fixedbugs/issue47317.dir/x.go
new file mode 100644
index 0000000000000000000000000000000000000000..83b5542144d8cc6d57eadbec8027a4d093cab23b
--- /dev/null
+++ b/go/test/fixedbugs/issue47317.dir/x.go
@@ -0,0 +1,17 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Issue 47317: ICE when calling ABI0 function via func value.
+
+package main
+
+func main() { F() }
+
+func F() interface{} {
+ g := G
+ g(1)
+ return G
+}
+
+func G(x int) [2]int
diff --git a/go/test/fixedbugs/issue48088.dir/a.go b/go/test/fixedbugs/issue48088.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..2bb879d557ed48e21eb64e0c62ee7c6c32e87655
--- /dev/null
+++ b/go/test/fixedbugs/issue48088.dir/a.go
@@ -0,0 +1,22 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type T1 struct {
+ *T2
+}
+
+type T2 struct {
+}
+
+func (t2 *T2) M() {
+}
+
+func F() {
+ f(T1.M)
+}
+
+func f(f func(T1)) {
+}
diff --git a/go/test/fixedbugs/issue48088.dir/b.go b/go/test/fixedbugs/issue48088.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..bdb1bb55c2d59ca94de267074fe80972b9bdda27
--- /dev/null
+++ b/go/test/fixedbugs/issue48088.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func F() {
+ a.F()
+}
diff --git a/go/test/fixedbugs/issue4879.dir/a.go b/go/test/fixedbugs/issue4879.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..7ee7c4860475f1616d19f863266e2191fe705c38
--- /dev/null
+++ b/go/test/fixedbugs/issue4879.dir/a.go
@@ -0,0 +1,33 @@
+package a
+
+import (
+ "unsafe"
+)
+
+type Collection struct {
+ root unsafe.Pointer
+}
+
+type nodeLoc struct{}
+
+type slice []int
+
+type maptype map[int]int
+
+func MakePrivateCollection() *Collection {
+ return &Collection{
+ root: unsafe.Pointer(&nodeLoc{}),
+ }
+}
+
+func MakePrivateCollection2() *Collection {
+ return &Collection{
+ root: unsafe.Pointer(&slice{}),
+ }
+}
+func MakePrivateCollection3() *Collection {
+ return &Collection{
+ root: unsafe.Pointer(&maptype{}),
+ }
+}
+
diff --git a/go/test/fixedbugs/issue4879.dir/b.go b/go/test/fixedbugs/issue4879.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..d8fb5693db903e528eb8f5d9747753d19a999f66
--- /dev/null
+++ b/go/test/fixedbugs/issue4879.dir/b.go
@@ -0,0 +1,9 @@
+package b
+
+import "./a"
+
+func F() {
+ a.MakePrivateCollection()
+ a.MakePrivateCollection2()
+ a.MakePrivateCollection3()
+}
diff --git a/go/test/fixedbugs/issue49016.dir/a.go b/go/test/fixedbugs/issue49016.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..36639b73d424bfe1e34978a03963043efee0a8b9
--- /dev/null
+++ b/go/test/fixedbugs/issue49016.dir/a.go
@@ -0,0 +1,36 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type Node interface {
+ Position()
+}
+
+type noder struct{}
+
+func (noder) Position() {}
+
+type Scope map[int][]Node
+
+func (s Scope) M1() Scope {
+ if x, ok := s[0]; ok {
+ return x[0].(struct {
+ noder
+ Scope
+ }).Scope
+ }
+ return nil
+}
+
+func (s Scope) M2() Scope {
+ if x, ok := s[0]; ok {
+ st, _ := x[0].(struct {
+ noder
+ Scope
+ })
+ return st.Scope
+ }
+ return nil
+}
diff --git a/go/test/fixedbugs/issue49016.dir/b.go b/go/test/fixedbugs/issue49016.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..1dd63f87b6a3469f044f1ba6edf2d3f416d663c0
--- /dev/null
+++ b/go/test/fixedbugs/issue49016.dir/b.go
@@ -0,0 +1,13 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+type t int
+
+func (t) m() {}
+
+func F1() interface{} { return struct{ t }{} }
+func F2() interface{} { return *new(struct{ t }) }
+func F3() interface{} { var x [1]struct{ t }; return x[0] }
diff --git a/go/test/fixedbugs/issue49016.dir/c.go b/go/test/fixedbugs/issue49016.dir/c.go
new file mode 100644
index 0000000000000000000000000000000000000000..2cc6681b950aab3e74aa729e5cc50e72898f0bea
--- /dev/null
+++ b/go/test/fixedbugs/issue49016.dir/c.go
@@ -0,0 +1,9 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package c
+
+import "./a"
+
+var _ = (&a.Scope{}).M1()
diff --git a/go/test/fixedbugs/issue49016.dir/d.go b/go/test/fixedbugs/issue49016.dir/d.go
new file mode 100644
index 0000000000000000000000000000000000000000..e933dc08e4bab921fc9ada3465eb15aa674f74f1
--- /dev/null
+++ b/go/test/fixedbugs/issue49016.dir/d.go
@@ -0,0 +1,9 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package d
+
+import "./a"
+
+var _ = (&a.Scope{}).M2()
diff --git a/go/test/fixedbugs/issue49016.dir/e.go b/go/test/fixedbugs/issue49016.dir/e.go
new file mode 100644
index 0000000000000000000000000000000000000000..5f43179c373b3d17b14121e52cc00c9567a46c67
--- /dev/null
+++ b/go/test/fixedbugs/issue49016.dir/e.go
@@ -0,0 +1,11 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package e
+
+import (
+ "./b"
+)
+
+var _ = b.F1()
diff --git a/go/test/fixedbugs/issue49016.dir/f.go b/go/test/fixedbugs/issue49016.dir/f.go
new file mode 100644
index 0000000000000000000000000000000000000000..2cd978eacef897771191633e84444bf6e3b37c11
--- /dev/null
+++ b/go/test/fixedbugs/issue49016.dir/f.go
@@ -0,0 +1,9 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package f
+
+import "./b"
+
+var _ = b.F2()
diff --git a/go/test/fixedbugs/issue49016.dir/g.go b/go/test/fixedbugs/issue49016.dir/g.go
new file mode 100644
index 0000000000000000000000000000000000000000..b90353fcff98862e8f0f99c1fe280ad4d052774d
--- /dev/null
+++ b/go/test/fixedbugs/issue49016.dir/g.go
@@ -0,0 +1,9 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package g
+
+import "./b"
+
+var _ = b.F3()
diff --git a/go/test/fixedbugs/issue49094.dir/a.go b/go/test/fixedbugs/issue49094.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..9ec0fd9f93e755de29da1aabc3a6d107c15f0535
--- /dev/null
+++ b/go/test/fixedbugs/issue49094.dir/a.go
@@ -0,0 +1,11 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type A struct{}
+
+func (a *A) f() bool {
+ return true
+}
diff --git a/go/test/fixedbugs/issue49094.dir/b.go b/go/test/fixedbugs/issue49094.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..f2361958ace346fa2709f19f5c500eead27fc0e5
--- /dev/null
+++ b/go/test/fixedbugs/issue49094.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func M(r *a.A) string {
+ return ""
+}
diff --git a/go/test/fixedbugs/issue49094.dir/p.go b/go/test/fixedbugs/issue49094.dir/p.go
new file mode 100644
index 0000000000000000000000000000000000000000..581faf19ac778ccd55470b5994faa8cbb6d416f3
--- /dev/null
+++ b/go/test/fixedbugs/issue49094.dir/p.go
@@ -0,0 +1,15 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+import (
+ "./b"
+)
+
+type S struct{}
+
+func (S) M() {
+ b.M(nil)
+}
diff --git a/go/test/fixedbugs/issue49143.dir/a.go b/go/test/fixedbugs/issue49143.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..5aefcd8780ca03a9481a1c5e3edd600dd462af9a
--- /dev/null
+++ b/go/test/fixedbugs/issue49143.dir/a.go
@@ -0,0 +1,24 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+import "sync"
+
+type Loader[K comparable, R any] struct {
+ batch *LoaderBatch[K, R]
+}
+
+func (l *Loader[K, R]) Load() error {
+ l.batch.f()
+ return nil
+}
+
+type LoaderBatch[K comparable, R any] struct {
+ once *sync.Once
+}
+
+func (b *LoaderBatch[K, R]) f() {
+ b.once.Do(func() {})
+}
diff --git a/go/test/fixedbugs/issue49143.dir/b.go b/go/test/fixedbugs/issue49143.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..48eecdbaaf53e899106b6016c33b76a97acdcd9f
--- /dev/null
+++ b/go/test/fixedbugs/issue49143.dir/b.go
@@ -0,0 +1,16 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+
+type Loaders struct {
+ Loader *a.Loader[int, int]
+}
+
+func NewLoaders() *Loaders {
+ return new(Loaders)
+}
diff --git a/go/test/fixedbugs/issue49143.dir/c.go b/go/test/fixedbugs/issue49143.dir/c.go
new file mode 100644
index 0000000000000000000000000000000000000000..89262e374aa1c44968f3ec83db55544475af693d
--- /dev/null
+++ b/go/test/fixedbugs/issue49143.dir/c.go
@@ -0,0 +1,15 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package c
+
+import "./b"
+
+type Resolver struct{}
+
+type todoResolver struct{ *Resolver }
+
+func (r *todoResolver) F() {
+ b.NewLoaders().Loader.Load()
+}
diff --git a/go/test/fixedbugs/issue49143.dir/p.go b/go/test/fixedbugs/issue49143.dir/p.go
new file mode 100644
index 0000000000000000000000000000000000000000..f11d2f22eb371c0209c81f733e2258f3a24606e4
--- /dev/null
+++ b/go/test/fixedbugs/issue49143.dir/p.go
@@ -0,0 +1,11 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+import (
+ "./c"
+)
+
+var _ = &c.Resolver{}
diff --git a/go/test/fixedbugs/issue4932.dir/foo.go b/go/test/fixedbugs/issue4932.dir/foo.go
new file mode 100644
index 0000000000000000000000000000000000000000..19b73a0e0384709495d09157370c4854e1fd910d
--- /dev/null
+++ b/go/test/fixedbugs/issue4932.dir/foo.go
@@ -0,0 +1,7 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package foo
+
+type Op struct{}
diff --git a/go/test/fixedbugs/issue4932.dir/state.go b/go/test/fixedbugs/issue4932.dir/state.go
new file mode 100644
index 0000000000000000000000000000000000000000..c017b9649d474e3d827564ba9a9195f7c41dc61f
--- /dev/null
+++ b/go/test/fixedbugs/issue4932.dir/state.go
@@ -0,0 +1,28 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package state
+
+import "./foo"
+
+func Public() {
+ var s Settings
+ s.op()
+}
+
+type State struct{}
+
+func (s *State) x(*Settings) {}
+
+type Settings struct{}
+
+func (c *Settings) x() {
+ run([]foo.Op{{}})
+}
+
+func run([]foo.Op) {}
+
+func (s *Settings) op() foo.Op {
+ return foo.Op{}
+}
diff --git a/go/test/fixedbugs/issue4932.dir/state2.go b/go/test/fixedbugs/issue4932.dir/state2.go
new file mode 100644
index 0000000000000000000000000000000000000000..50f75db2cea1006235c427a70b4c46c3ed8aecf6
--- /dev/null
+++ b/go/test/fixedbugs/issue4932.dir/state2.go
@@ -0,0 +1,9 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package state2
+
+import "./state"
+
+type Foo *state.State
diff --git a/go/test/fixedbugs/issue4964.dir/a.go b/go/test/fixedbugs/issue4964.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..216f352ca959e5fb4e30744b2e8839154665c89f
--- /dev/null
+++ b/go/test/fixedbugs/issue4964.dir/a.go
@@ -0,0 +1,25 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+var global, global2 *int
+
+type T struct {
+ Pointer *int
+}
+
+//go:noinline
+func Store(t *T) {
+ global = t.Pointer
+}
+
+//go:noinline
+func Store2(t *T) {
+ global2 = t.Pointer
+}
+
+func Get() *int {
+ return global
+}
diff --git a/go/test/fixedbugs/issue4964.dir/b.go b/go/test/fixedbugs/issue4964.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..42a6f1d761a8c8451a68cbcc3df652b119032f1e
--- /dev/null
+++ b/go/test/fixedbugs/issue4964.dir/b.go
@@ -0,0 +1,34 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+func F() {
+ // store 1 in a.global
+ x, y := 1, 2
+ t := a.T{Pointer: &x}
+ a.Store(&t)
+ _ = y
+}
+
+func G() {
+ // store 4 in a.global2
+ x, y := 3, 4
+ t := a.T{Pointer: &y}
+ a.Store2(&t)
+ _ = x
+}
+
+func main() {
+ F()
+ G()
+ p := a.Get()
+ n := *p
+ if n != 1 {
+ println(n, "!= 1")
+ panic("n != 1")
+ }
+}
diff --git a/go/test/fixedbugs/issue50788.dir/a.go b/go/test/fixedbugs/issue50788.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..0f786d494c9a77612272a520c022add42a165b0a
--- /dev/null
+++ b/go/test/fixedbugs/issue50788.dir/a.go
@@ -0,0 +1,9 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type T[P any] struct {
+ _ P
+}
diff --git a/go/test/fixedbugs/issue50788.dir/b.go b/go/test/fixedbugs/issue50788.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..97ae20801985abdbb3bfc3dd07f2902b6c93771e
--- /dev/null
+++ b/go/test/fixedbugs/issue50788.dir/b.go
@@ -0,0 +1,9 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+type T a.T[T] // ERROR "invalid recursive type T\n.*T refers to a\.T\n.*a\.T refers to T"
diff --git a/go/test/fixedbugs/issue5105.dir/a.go b/go/test/fixedbugs/issue5105.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..f20abb98bfac7cc527bc2990a1d4e7fe4ccf40c8
--- /dev/null
+++ b/go/test/fixedbugs/issue5105.dir/a.go
@@ -0,0 +1,7 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+var A = [2]string{"hello", "world"}
diff --git a/go/test/fixedbugs/issue5105.dir/b.go b/go/test/fixedbugs/issue5105.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..b12e739e33a0db8e2758d003c58b029a035c2090
--- /dev/null
+++ b/go/test/fixedbugs/issue5105.dir/b.go
@@ -0,0 +1,15 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+var B = [2]string{"world", "hello"}
+
+func main() {
+ if a.A[0] != B[1] {
+ panic("bad hello")
+ }
+}
diff --git a/go/test/fixedbugs/issue5125.dir/bug.go b/go/test/fixedbugs/issue5125.dir/bug.go
new file mode 100644
index 0000000000000000000000000000000000000000..2fdf0f9bb8b1630978110b9d9450b6c2b53629fb
--- /dev/null
+++ b/go/test/fixedbugs/issue5125.dir/bug.go
@@ -0,0 +1,17 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bug
+
+type Node interface {
+ Eval(s *Scene)
+}
+
+type plug struct {
+ node Node
+}
+
+type Scene struct {
+ changed map[plug]bool
+}
diff --git a/go/test/fixedbugs/issue5125.dir/main.go b/go/test/fixedbugs/issue5125.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..47acdeba8a9500b64573ab8f4fc57b71855d96d2
--- /dev/null
+++ b/go/test/fixedbugs/issue5125.dir/main.go
@@ -0,0 +1,10 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import _ "./bug"
+
+func main() {
+}
diff --git a/go/test/fixedbugs/issue51291.dir/a.go b/go/test/fixedbugs/issue51291.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..21e2cd6adfa1380c0bae41c2819bba34c6aeb8a1
--- /dev/null
+++ b/go/test/fixedbugs/issue51291.dir/a.go
@@ -0,0 +1,9 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type TypeA string
+
+const StrA TypeA = "s"
diff --git a/go/test/fixedbugs/issue51291.dir/b.go b/go/test/fixedbugs/issue51291.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..26b2c7872ed5db6788f8c2ba502e15067fbf9145
--- /dev/null
+++ b/go/test/fixedbugs/issue51291.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+type TypeB string
+
+const StrB TypeB = TypeB(a.StrA)
diff --git a/go/test/fixedbugs/issue52128.dir/a.go b/go/test/fixedbugs/issue52128.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..0abf831c6fd13c5f8b00cdb3d6e2650f69642b76
--- /dev/null
+++ b/go/test/fixedbugs/issue52128.dir/a.go
@@ -0,0 +1,21 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type I interface{}
+
+type F func()
+
+type s struct {
+ f F
+}
+
+func NewWithF(f F) *s {
+ return &s{f: f}
+}
+
+func NewWithFuncI(func() I) *s {
+ return &s{}
+}
diff --git a/go/test/fixedbugs/issue52128.dir/b.go b/go/test/fixedbugs/issue52128.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..86f6ed7e056229b3b1abc1cab23e7bc6a1b7026a
--- /dev/null
+++ b/go/test/fixedbugs/issue52128.dir/b.go
@@ -0,0 +1,17 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import (
+ "./a"
+)
+
+type S struct{}
+
+func (s *S) M1() a.I {
+ return a.NewWithF(s.M2)
+}
+
+func (s *S) M2() {}
diff --git a/go/test/fixedbugs/issue52128.dir/p.go b/go/test/fixedbugs/issue52128.dir/p.go
new file mode 100644
index 0000000000000000000000000000000000000000..d3f3dbbfb9bc06efc683b92160e7f83582bc7459
--- /dev/null
+++ b/go/test/fixedbugs/issue52128.dir/p.go
@@ -0,0 +1,14 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+import (
+ "./a"
+ "./b"
+)
+
+func f() {
+ a.NewWithFuncI((&b.S{}).M1)
+}
diff --git a/go/test/fixedbugs/issue52279.dir/lib.go b/go/test/fixedbugs/issue52279.dir/lib.go
new file mode 100644
index 0000000000000000000000000000000000000000..e20de30bd5c02c8db29294e71af29a73c832dc8c
--- /dev/null
+++ b/go/test/fixedbugs/issue52279.dir/lib.go
@@ -0,0 +1,23 @@
+package lib
+
+type FMap[K comparable, V comparable] map[K]V
+
+//go:noinline
+func (m FMap[K, V]) Flip() FMap[V, K] {
+ out := make(FMap[V, K])
+ return out
+}
+
+type MyType uint8
+
+const (
+ FIRST MyType = 0
+)
+
+var typeStrs = FMap[MyType, string]{
+ FIRST: "FIRST",
+}
+
+func (self MyType) String() string {
+ return typeStrs[self]
+}
diff --git a/go/test/fixedbugs/issue52279.dir/main.go b/go/test/fixedbugs/issue52279.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..8c7e069c5b924477770eeb51fabf5ea7bee7f27e
--- /dev/null
+++ b/go/test/fixedbugs/issue52279.dir/main.go
@@ -0,0 +1,5 @@
+package main
+
+import "./lib"
+
+func main() { lib.FIRST.String() }
diff --git a/go/test/fixedbugs/issue5259.dir/bug.go b/go/test/fixedbugs/issue5259.dir/bug.go
new file mode 100644
index 0000000000000000000000000000000000000000..8512461686bcd5cc413e10c056f771102b6fe5dd
--- /dev/null
+++ b/go/test/fixedbugs/issue5259.dir/bug.go
@@ -0,0 +1,17 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bug
+
+type S struct {
+ F func()
+}
+
+type X interface {
+ Bar()
+}
+
+func Foo(x X) *S {
+ return &S{F: x.Bar}
+}
diff --git a/go/test/fixedbugs/issue5259.dir/main.go b/go/test/fixedbugs/issue5259.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..ad1da78f5fca350a7b3f0e488c5e5a9a46b6444c
--- /dev/null
+++ b/go/test/fixedbugs/issue5259.dir/main.go
@@ -0,0 +1,16 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./bug"
+
+type foo int
+
+func (f *foo) Bar() {
+}
+
+func main() {
+ bug.Foo(new(foo))
+}
diff --git a/go/test/fixedbugs/issue52590.dir/a.go b/go/test/fixedbugs/issue52590.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..20031e60c77170ca1d84a3d2b563257c299eb453
--- /dev/null
+++ b/go/test/fixedbugs/issue52590.dir/a.go
@@ -0,0 +1,68 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+import "unsafe"
+
+func Append() {
+ _ = append(appendArgs())
+}
+
+func Delete() {
+ delete(deleteArgs())
+}
+
+func Print() {
+ print(ints())
+}
+
+func Println() {
+ println(ints())
+}
+
+func Complex() {
+ _ = complex(float64s())
+}
+
+func Copy() {
+ copy(slices())
+}
+
+func UnsafeAdd() {
+ _ = unsafe.Add(unsafeAdd())
+}
+
+func UnsafeSlice() {
+ _ = unsafe.Slice(unsafeSlice())
+}
+
+func appendArgs() ([]int, int) {
+ return []int{}, 0
+}
+
+func deleteArgs() (map[int]int, int) {
+ return map[int]int{}, 0
+}
+
+func ints() (int, int) {
+ return 1, 1
+}
+
+func float64s() (float64, float64) {
+ return 0, 0
+}
+
+func slices() ([]int, []int) {
+ return []int{}, []int{}
+}
+
+func unsafeAdd() (unsafe.Pointer, int) {
+ return nil, 0
+}
+
+func unsafeSlice() (*byte, int) {
+ var p [10]byte
+ return &p[0], 0
+}
diff --git a/go/test/fixedbugs/issue52590.dir/b.go b/go/test/fixedbugs/issue52590.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..264e8d10a6b6f135c0f757a9fa4077885ac644de
--- /dev/null
+++ b/go/test/fixedbugs/issue52590.dir/b.go
@@ -0,0 +1,18 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func f() {
+ a.Append()
+ a.Delete()
+ a.Print()
+ a.Println()
+ a.Complex()
+ a.Copy()
+ a.UnsafeAdd()
+ a.UnsafeSlice()
+}
diff --git a/go/test/fixedbugs/issue5260.dir/a.go b/go/test/fixedbugs/issue5260.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..5a2c99f65c726b37edb241212b55ff960fb46857
--- /dev/null
+++ b/go/test/fixedbugs/issue5260.dir/a.go
@@ -0,0 +1,7 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+const BOM = "\uFEFF"
diff --git a/go/test/fixedbugs/issue5260.dir/b.go b/go/test/fixedbugs/issue5260.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..299b75e4a7cdd4a00c2d13390f604d29f0760e7b
--- /dev/null
+++ b/go/test/fixedbugs/issue5260.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+func main() {
+ _ = a.BOM
+}
diff --git a/go/test/fixedbugs/issue52856.dir/a.go b/go/test/fixedbugs/issue52856.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..36af7e04cd0f8a5b060b2092e82b044b29b21446
--- /dev/null
+++ b/go/test/fixedbugs/issue52856.dir/a.go
@@ -0,0 +1,9 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func F() any {
+ return struct{ int }{0}
+}
diff --git a/go/test/fixedbugs/issue52856.dir/main.go b/go/test/fixedbugs/issue52856.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..732368d3a7c79256f9e1f0da89c0eae1169d2792
--- /dev/null
+++ b/go/test/fixedbugs/issue52856.dir/main.go
@@ -0,0 +1,19 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+func F() any {
+ return struct{ int }{0}
+}
+
+func main() {
+ _, ok1 := F().(struct{ int })
+ _, ok2 := a.F().(struct{ int })
+ if !ok1 || ok2 {
+ panic(0)
+ }
+}
diff --git a/go/test/fixedbugs/issue52862.dir/a.go b/go/test/fixedbugs/issue52862.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..ef4ce2025c85b1669485a8ba60e1462340d59f7b
--- /dev/null
+++ b/go/test/fixedbugs/issue52862.dir/a.go
@@ -0,0 +1,9 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func F() complex128 {
+ return 0+0i
+}
diff --git a/go/test/fixedbugs/issue52862.dir/b.go b/go/test/fixedbugs/issue52862.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..739af663f72406b831ea752167201e07cadba983
--- /dev/null
+++ b/go/test/fixedbugs/issue52862.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func F() complex128 {
+ return a.F()
+}
diff --git a/go/test/fixedbugs/issue5291.dir/pkg1.go b/go/test/fixedbugs/issue5291.dir/pkg1.go
new file mode 100644
index 0000000000000000000000000000000000000000..b1c893ac83e63b0c2e4aff68926eb3120c95c5a9
--- /dev/null
+++ b/go/test/fixedbugs/issue5291.dir/pkg1.go
@@ -0,0 +1,34 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package pkg1
+
+import (
+ "runtime"
+)
+
+type T2 *[]string
+
+type Data struct {
+ T1 *[]T2
+}
+
+func CrashCall() (err error) {
+ var d Data
+
+ for count := 0; count < 10; count++ {
+ runtime.GC()
+
+ len := 2 // crash when >=2
+ x := make([]T2, len)
+
+ d = Data{T1: &x}
+
+ for j := 0; j < len; j++ {
+ y := make([]string, 1)
+ (*d.T1)[j] = &y
+ }
+ }
+ return nil
+}
diff --git a/go/test/fixedbugs/issue5291.dir/prog.go b/go/test/fixedbugs/issue5291.dir/prog.go
new file mode 100644
index 0000000000000000000000000000000000000000..8301091bd8858ac4590a5c48674f6c75c014af82
--- /dev/null
+++ b/go/test/fixedbugs/issue5291.dir/prog.go
@@ -0,0 +1,17 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./pkg1"
+)
+
+type message struct { // Presence of this creates a crash
+ data pkg1.Data
+}
+
+func main() {
+ pkg1.CrashCall()
+}
diff --git a/go/test/fixedbugs/issue5470.dir/a.go b/go/test/fixedbugs/issue5470.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..302822d238707a9d05782550d512c66e147b5c40
--- /dev/null
+++ b/go/test/fixedbugs/issue5470.dir/a.go
@@ -0,0 +1,27 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type Foo interface {
+ Hi() string
+}
+
+func Test1() Foo { return make(tst1) }
+
+type tst1 map[string]bool
+
+func (r tst1) Hi() string { return "Hi!" }
+
+func Test2() Foo { return make(tst2, 0) }
+
+type tst2 []string
+
+func (r tst2) Hi() string { return "Hi!" }
+
+func Test3() Foo { return make(tst3) }
+
+type tst3 chan string
+
+func (r tst3) Hi() string { return "Hi!" }
diff --git a/go/test/fixedbugs/issue5470.dir/b.go b/go/test/fixedbugs/issue5470.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..0801c149cfe26b0dc97c405cd929acac0a34dd08
--- /dev/null
+++ b/go/test/fixedbugs/issue5470.dir/b.go
@@ -0,0 +1,13 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func main() {
+ a.Test1()
+ a.Test2()
+ a.Test3()
+}
diff --git a/go/test/fixedbugs/issue54912.dir/a.go b/go/test/fixedbugs/issue54912.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..b425223da989b41e16f0052e67b9cd57c1dafe48
--- /dev/null
+++ b/go/test/fixedbugs/issue54912.dir/a.go
@@ -0,0 +1,18 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test that inlining a function literal that captures both a type
+// switch case variable and another local variable works correctly.
+
+package a
+
+func F(p *int, x any) func() {
+ switch x := x.(type) {
+ case int:
+ return func() {
+ *p += x
+ }
+ }
+ return nil
+}
diff --git a/go/test/fixedbugs/issue54912.dir/main.go b/go/test/fixedbugs/issue54912.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..67b9012b36b5b79095e9d09a75097b22119da5c9
--- /dev/null
+++ b/go/test/fixedbugs/issue54912.dir/main.go
@@ -0,0 +1,11 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "test/a"
+
+func main() {
+ a.F(new(int), 0)()
+}
diff --git a/go/test/fixedbugs/issue5614.dir/rethinkgo.go b/go/test/fixedbugs/issue5614.dir/rethinkgo.go
new file mode 100644
index 0000000000000000000000000000000000000000..4ae66d679ea59fc47c07fe7c2b2ad6dd334d5382
--- /dev/null
+++ b/go/test/fixedbugs/issue5614.dir/rethinkgo.go
@@ -0,0 +1,16 @@
+package rethinkgo
+
+type Session struct {
+}
+
+func (s *Session) Run(query Exp) *int { return nil }
+
+type List []interface{}
+
+type Exp struct {
+ args []interface{}
+}
+
+func (e Exp) UseOutdated(useOutdated bool) Exp {
+ return Exp{args: List{e, useOutdated}}
+}
diff --git a/go/test/fixedbugs/issue5614.dir/x.go b/go/test/fixedbugs/issue5614.dir/x.go
new file mode 100644
index 0000000000000000000000000000000000000000..7e4f3a7e6b9bb13944e4455ec03e4f9c065d5722
--- /dev/null
+++ b/go/test/fixedbugs/issue5614.dir/x.go
@@ -0,0 +1,7 @@
+package x
+
+import "./rethinkgo"
+
+var S *rethinkgo.Session
+
+
diff --git a/go/test/fixedbugs/issue5614.dir/y.go b/go/test/fixedbugs/issue5614.dir/y.go
new file mode 100644
index 0000000000000000000000000000000000000000..97cc93a79d5d7bdf6265122a5337c7861f2c5c3d
--- /dev/null
+++ b/go/test/fixedbugs/issue5614.dir/y.go
@@ -0,0 +1,5 @@
+package y
+
+import "./x"
+
+var T = x.S
diff --git a/go/test/fixedbugs/issue56280.dir/a.go b/go/test/fixedbugs/issue56280.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..289b06a7b3ab322473e0c22cf2dfcc2a29e81a70
--- /dev/null
+++ b/go/test/fixedbugs/issue56280.dir/a.go
@@ -0,0 +1,11 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func F() { // ERROR "can inline F"
+ g(0) // ERROR "inlining call to g\[go.shape.int\]"
+}
+
+func g[T any](_ T) {} // ERROR "can inline g\[int\]" "can inline g\[go.shape.int\]" "inlining call to g\[go.shape.int\]"
diff --git a/go/test/fixedbugs/issue56280.dir/main.go b/go/test/fixedbugs/issue56280.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..06092b17f0068080978ce5ff8d013bf8e1e7a340
--- /dev/null
+++ b/go/test/fixedbugs/issue56280.dir/main.go
@@ -0,0 +1,11 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "test/a"
+
+func main() { // ERROR "can inline main"
+ a.F() // ERROR "inlining call to a.F" "inlining call to a.g\[go.shape.int\]"
+}
diff --git a/go/test/fixedbugs/issue56778.dir/a.go b/go/test/fixedbugs/issue56778.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..d01aea4d1413bf03ae28a8ec76adc8e086e22a1b
--- /dev/null
+++ b/go/test/fixedbugs/issue56778.dir/a.go
@@ -0,0 +1,18 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type A struct {
+ New func() any
+}
+
+func NewA(i int) *A {
+ return &A{
+ New: func() any {
+ _ = i
+ return nil
+ },
+ }
+}
diff --git a/go/test/fixedbugs/issue56778.dir/b.go b/go/test/fixedbugs/issue56778.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..d49f7e57080ba85e73d457b5b77ba5b8fc4531c1
--- /dev/null
+++ b/go/test/fixedbugs/issue56778.dir/b.go
@@ -0,0 +1,9 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+var _ = a.NewA(0)
diff --git a/go/test/fixedbugs/issue5755.dir/a.go b/go/test/fixedbugs/issue5755.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..aa398e82b257c1b0213445d52377cc74f0640088
--- /dev/null
+++ b/go/test/fixedbugs/issue5755.dir/a.go
@@ -0,0 +1,60 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type I interface {
+ F()
+}
+
+type foo1 []byte
+type foo2 []rune
+type foo3 []uint8
+type foo4 []int32
+type foo5 string
+type foo6 string
+type foo7 string
+type foo8 string
+type foo9 string
+
+func (f foo1) F() { return }
+func (f foo2) F() { return }
+func (f foo3) F() { return }
+func (f foo4) F() { return }
+func (f foo5) F() { return }
+func (f foo6) F() { return }
+func (f foo7) F() { return }
+func (f foo8) F() { return }
+func (f foo9) F() { return }
+
+func Test1(s string) I { return foo1(s) }
+func Test2(s string) I { return foo2(s) }
+func Test3(s string) I { return foo3(s) }
+func Test4(s string) I { return foo4(s) }
+func Test5(s []byte) I { return foo5(s) }
+func Test6(s []rune) I { return foo6(s) }
+func Test7(s []uint8) I { return foo7(s) }
+func Test8(s []int32) I { return foo8(s) }
+func Test9(s int) I { return foo9(s) }
+
+type bar map[int]int
+
+func (b bar) F() { return }
+
+func TestBar() I { return bar{1: 2} }
+
+type baz int
+
+func IsBaz(x interface{}) bool { _, ok := x.(baz); return ok }
+
+type baz2 int
+
+func IsBaz2(x interface{}) bool {
+ switch x.(type) {
+ case baz2:
+ return true
+ default:
+ return false
+ }
+}
diff --git a/go/test/fixedbugs/issue5755.dir/main.go b/go/test/fixedbugs/issue5755.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..6d515f26a637cc9e2572c9febda88cf5cf05629d
--- /dev/null
+++ b/go/test/fixedbugs/issue5755.dir/main.go
@@ -0,0 +1,23 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+func main() {
+ a.Test1("frumious")
+ a.Test2("frumious")
+ a.Test3("frumious")
+ a.Test4("frumious")
+
+ a.Test5(nil)
+ a.Test6(nil)
+ a.Test7(nil)
+ a.Test8(nil)
+ a.Test9(0)
+
+ a.TestBar()
+ a.IsBaz(nil)
+}
diff --git a/go/test/fixedbugs/issue58339.dir/a.go b/go/test/fixedbugs/issue58339.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..22cbe0c6f9d5342bcd74a4494461aedd2fafea10
--- /dev/null
+++ b/go/test/fixedbugs/issue58339.dir/a.go
@@ -0,0 +1,17 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func Assert(msgAndArgs ...any) {
+}
+
+func Run() int {
+ Assert("%v")
+ return 0
+}
+
+func Run2() int {
+ return Run()
+}
diff --git a/go/test/fixedbugs/issue58339.dir/b.go b/go/test/fixedbugs/issue58339.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..1736ec7adb42e8d1363b85533514bbb40e5f2aff
--- /dev/null
+++ b/go/test/fixedbugs/issue58339.dir/b.go
@@ -0,0 +1,9 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+var A = a.Run2()
diff --git a/go/test/fixedbugs/issue58563.dir/a.go b/go/test/fixedbugs/issue58563.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..2b716c1b334a0586ca4a0ce28bd1c42ad5242137
--- /dev/null
+++ b/go/test/fixedbugs/issue58563.dir/a.go
@@ -0,0 +1,13 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func Start() interface{ Stop() } {
+ return new(Stopper)
+}
+
+type Stopper struct{}
+
+func (s *Stopper) Stop() {}
diff --git a/go/test/fixedbugs/issue58563.dir/main.go b/go/test/fixedbugs/issue58563.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..18a90fcf056c0f515fc477aefdcefbb9a755ff96
--- /dev/null
+++ b/go/test/fixedbugs/issue58563.dir/main.go
@@ -0,0 +1,16 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "test/a"
+
+func main() {
+ stop := start()
+ defer stop()
+}
+
+func start() func() {
+ return a.Start().Stop
+}
diff --git a/go/test/fixedbugs/issue5910.dir/a.go b/go/test/fixedbugs/issue5910.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..b236c15c7d39efc6d6005cbc60e1171252de1282
--- /dev/null
+++ b/go/test/fixedbugs/issue5910.dir/a.go
@@ -0,0 +1,22 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type Package struct {
+ name string
+}
+
+type Future struct {
+ result chan struct {
+ *Package
+ error
+ }
+}
+
+func (t *Future) Result() (*Package, error) {
+ result := <-t.result
+ t.result <- result
+ return result.Package, result.error
+}
diff --git a/go/test/fixedbugs/issue5910.dir/main.go b/go/test/fixedbugs/issue5910.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..80ddfbbca3641a378951dbe4242b31a8076c7283
--- /dev/null
+++ b/go/test/fixedbugs/issue5910.dir/main.go
@@ -0,0 +1,12 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+func main() {
+ f := new(a.Future)
+ f.Result()
+}
diff --git a/go/test/fixedbugs/issue5957.dir/a.go b/go/test/fixedbugs/issue5957.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..7411d5fcd54c0c2e2cb3761686054e2afcc4a408
--- /dev/null
+++ b/go/test/fixedbugs/issue5957.dir/a.go
@@ -0,0 +1,3 @@
+package surprise
+
+var X int
diff --git a/go/test/fixedbugs/issue5957.dir/b.go b/go/test/fixedbugs/issue5957.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..9bc561b9ce5ac82dfaae964888a3ce2fde64e4e7
--- /dev/null
+++ b/go/test/fixedbugs/issue5957.dir/b.go
@@ -0,0 +1,2 @@
+package surprise2
+
diff --git a/go/test/fixedbugs/issue5957.dir/c.go b/go/test/fixedbugs/issue5957.dir/c.go
new file mode 100644
index 0000000000000000000000000000000000000000..382e234537eb04574eb7acdaa60717a53d6b63d7
--- /dev/null
+++ b/go/test/fixedbugs/issue5957.dir/c.go
@@ -0,0 +1,12 @@
+package p
+
+import (
+ "./a" // ERROR "imported and not used: \x22test/a\x22 as surprise|imported and not used: surprise|\x22test/a\x22 imported as surprise and not used"
+ "./b" // ERROR "imported and not used: \x22test/b\x22 as surprise2|imported and not used: surprise2|\x22test/b\x22 imported as surprise2 and not used"
+ b "./b" // ERROR "imported and not used: \x22test/b\x22$|imported and not used: surprise2|\x22test/b\x22 imported and not used"
+ foo "math" // ERROR "imported and not used: \x22math\x22 as foo|imported and not used: math|\x22math\x22 imported as foo and not used"
+ "fmt" // actually used
+ "strings" // ERROR "imported and not used: \x22strings\x22|imported and not used: strings|\x22strings\x22 imported and not used"
+)
+
+var _ = fmt.Printf
diff --git a/go/test/fixedbugs/issue59709.dir/aconfig.go b/go/test/fixedbugs/issue59709.dir/aconfig.go
new file mode 100644
index 0000000000000000000000000000000000000000..01b3cf483ba11ba8f3e83c28f2085874d6866125
--- /dev/null
+++ b/go/test/fixedbugs/issue59709.dir/aconfig.go
@@ -0,0 +1,10 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package aconfig
+
+type Config struct {
+ name string
+ blah int
+}
diff --git a/go/test/fixedbugs/issue59709.dir/bresource.go b/go/test/fixedbugs/issue59709.dir/bresource.go
new file mode 100644
index 0000000000000000000000000000000000000000..9fae0994b0c844903a556f42760d65e43e30e54e
--- /dev/null
+++ b/go/test/fixedbugs/issue59709.dir/bresource.go
@@ -0,0 +1,27 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bresource
+
+type Resource[T any] struct {
+ name string
+ initializer Initializer[T]
+ cfg ResConfig
+ value T
+}
+
+func Should[T any](r *Resource[T], e error) bool {
+ return r.cfg.ShouldRetry(e)
+}
+
+type ResConfig struct {
+ ShouldRetry func(error) bool
+ TearDown func()
+}
+
+type Initializer[T any] func(*int) (T, error)
+
+func New[T any](name string, f Initializer[T], cfg ResConfig) *Resource[T] {
+ return &Resource[T]{name: name, initializer: f, cfg: cfg}
+}
diff --git a/go/test/fixedbugs/issue59709.dir/cmem.go b/go/test/fixedbugs/issue59709.dir/cmem.go
new file mode 100644
index 0000000000000000000000000000000000000000..43c4fe9901bff27029d04a1f220858f983ec0ba7
--- /dev/null
+++ b/go/test/fixedbugs/issue59709.dir/cmem.go
@@ -0,0 +1,37 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cmem
+
+import (
+ "./aconfig"
+ "./bresource"
+)
+
+type MemT *int
+
+var G int
+
+type memResource struct {
+ x *int
+}
+
+func (m *memResource) initialize(*int) (res *int, err error) {
+ return nil, nil
+}
+
+func (m *memResource) teardown() {
+}
+
+func NewResource(cfg *aconfig.Config) *bresource.Resource[*int] {
+ res := &memResource{
+ x: &G,
+ }
+
+ return bresource.New("Mem", res.initialize, bresource.ResConfig{
+ // We always would want to retry the Memcache initialization.
+ ShouldRetry: func(error) bool { return true },
+ TearDown: res.teardown,
+ })
+}
diff --git a/go/test/fixedbugs/issue59709.dir/dcache.go b/go/test/fixedbugs/issue59709.dir/dcache.go
new file mode 100644
index 0000000000000000000000000000000000000000..ea6321974e9c33cc80701098dea2741a06ad6cde
--- /dev/null
+++ b/go/test/fixedbugs/issue59709.dir/dcache.go
@@ -0,0 +1,39 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package dcache
+
+import (
+ "./aconfig"
+ "./bresource"
+ "./cmem"
+)
+
+type Module struct {
+ cfg *aconfig.Config
+ err error
+ last any
+}
+
+//go:noinline
+func TD() {
+}
+
+func (m *Module) Configure(x string) error {
+ if m.err != nil {
+ return m.err
+ }
+ res := cmem.NewResource(m.cfg)
+ m.last = res
+
+ return nil
+}
+
+func (m *Module) Blurb(x string, e error) bool {
+ res, ok := m.last.(*bresource.Resource[*int])
+ if !ok {
+ panic("bad")
+ }
+ return bresource.Should(res, e)
+}
diff --git a/go/test/fixedbugs/issue59709.dir/main.go b/go/test/fixedbugs/issue59709.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..c699a01fc140838b61849687fb9ce5daa56e6c18
--- /dev/null
+++ b/go/test/fixedbugs/issue59709.dir/main.go
@@ -0,0 +1,17 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./dcache"
+)
+
+func main() {
+ var m dcache.Module
+ m.Configure("x")
+ m.Configure("y")
+ var e error
+ m.Blurb("x", e)
+}
diff --git a/go/test/fixedbugs/issue60945.dir/a.go b/go/test/fixedbugs/issue60945.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..663a0cfc69e02aaa504d7b8419a734041d4187b3
--- /dev/null
+++ b/go/test/fixedbugs/issue60945.dir/a.go
@@ -0,0 +1,22 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type S struct{}
+
+func callClosure(closure func()) {
+ closure()
+}
+
+func (s *S) M() {
+ callClosure(func() {
+ defer f(s.m) // prevent closures to be inlined.
+ })
+}
+
+func (s *S) m() {}
+
+//go:noinline
+func f(a ...any) {}
diff --git a/go/test/fixedbugs/issue60945.dir/b.go b/go/test/fixedbugs/issue60945.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..e60d9dc7c1abd35b1841896270081a431a3029e5
--- /dev/null
+++ b/go/test/fixedbugs/issue60945.dir/b.go
@@ -0,0 +1,9 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+var _ = (&a.S{}).M
diff --git a/go/test/fixedbugs/issue62498.dir/a.go b/go/test/fixedbugs/issue62498.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..68f97475ab62c58f432a2a4593b77d8fce94b4ce
--- /dev/null
+++ b/go/test/fixedbugs/issue62498.dir/a.go
@@ -0,0 +1,13 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func One(L any) {
+ func() {
+ defer F(L)
+ }()
+}
+
+func F(any) {}
diff --git a/go/test/fixedbugs/issue62498.dir/main.go b/go/test/fixedbugs/issue62498.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..e55a24fb3a081ef9ffb15a4439a052a2998e4c07
--- /dev/null
+++ b/go/test/fixedbugs/issue62498.dir/main.go
@@ -0,0 +1,18 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+func main() {
+ a.One(nil)
+ Two(nil)
+}
+
+func Two(L any) {
+ func() {
+ defer a.F(L)
+ }()
+}
diff --git a/go/test/fixedbugs/issue6295.dir/p0.go b/go/test/fixedbugs/issue6295.dir/p0.go
new file mode 100644
index 0000000000000000000000000000000000000000..d4d4da7b3531b5942d730cc414cf00587b7daa52
--- /dev/null
+++ b/go/test/fixedbugs/issue6295.dir/p0.go
@@ -0,0 +1,13 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p0
+
+type T0 interface {
+ m0()
+}
+
+type S0 struct{}
+
+func (S0) m0() {}
diff --git a/go/test/fixedbugs/issue6295.dir/p1.go b/go/test/fixedbugs/issue6295.dir/p1.go
new file mode 100644
index 0000000000000000000000000000000000000000..26efae7409653bd2c8538c885ab74eea20c437f0
--- /dev/null
+++ b/go/test/fixedbugs/issue6295.dir/p1.go
@@ -0,0 +1,26 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p1
+
+import "./p0"
+
+type T1 interface {
+ p0.T0
+ m1()
+}
+
+type S1 struct {
+ p0.S0
+}
+
+func (S1) m1() {}
+
+func NewT0() p0.T0 {
+ return S1{}
+}
+
+func NewT1() T1 {
+ return S1{}
+}
diff --git a/go/test/fixedbugs/issue6295.dir/p2.go b/go/test/fixedbugs/issue6295.dir/p2.go
new file mode 100644
index 0000000000000000000000000000000000000000..f5b6ffd0a1320123ac337b090e8d1c93291b5004
--- /dev/null
+++ b/go/test/fixedbugs/issue6295.dir/p2.go
@@ -0,0 +1,19 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./p0"
+ "./p1"
+)
+
+var (
+ _ p0.T0 = p0.S0{}
+ _ p0.T0 = p1.S1{}
+ _ p0.T0 = p1.NewT0()
+ _ p0.T0 = p1.NewT1() // same as p1.S1{}
+)
+
+func main() {}
diff --git a/go/test/fixedbugs/issue6513.dir/a.go b/go/test/fixedbugs/issue6513.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..e5536feb61a46058f50ff3c6e5e595769f947f4a
--- /dev/null
+++ b/go/test/fixedbugs/issue6513.dir/a.go
@@ -0,0 +1,7 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type T struct{ int }
diff --git a/go/test/fixedbugs/issue6513.dir/b.go b/go/test/fixedbugs/issue6513.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..ce3d52ec1ab78e92f90ef6baaeefb4e7415d7e4a
--- /dev/null
+++ b/go/test/fixedbugs/issue6513.dir/b.go
@@ -0,0 +1,9 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+type U struct{ a.T }
diff --git a/go/test/fixedbugs/issue6513.dir/main.go b/go/test/fixedbugs/issue6513.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..8d8c02b9076e21b8ef5058a17737d9daf8b63beb
--- /dev/null
+++ b/go/test/fixedbugs/issue6513.dir/main.go
@@ -0,0 +1,16 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./a"
+ "./b"
+)
+
+func main() {
+ var t a.T
+ var u b.U
+ _, _ = t, u
+}
diff --git a/go/test/fixedbugs/issue65957.dir/a.go b/go/test/fixedbugs/issue65957.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..284ec4af9f2df586e16291ff57b1124c4360e3fb
--- /dev/null
+++ b/go/test/fixedbugs/issue65957.dir/a.go
@@ -0,0 +1,12 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+var s any
+
+//go:noinline
+func F() {
+ s = new([4]int32)
+}
diff --git a/go/test/fixedbugs/issue65957.dir/main.go b/go/test/fixedbugs/issue65957.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..89b8a28234513120c7a6c8a135e16fe436306711
--- /dev/null
+++ b/go/test/fixedbugs/issue65957.dir/main.go
@@ -0,0 +1,19 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./a"
+ "reflect"
+)
+
+var s = []rune{0, 1, 2, 3}
+
+func main() {
+ m := map[any]int{}
+ k := reflect.New(reflect.ArrayOf(4, reflect.TypeOf(int32(0)))).Elem().Interface()
+ m[k] = 1
+ a.F()
+}
diff --git a/go/test/fixedbugs/issue6789.dir/a.go b/go/test/fixedbugs/issue6789.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..9c90e0740cda5865e09de1f323b7e825dff2218c
--- /dev/null
+++ b/go/test/fixedbugs/issue6789.dir/a.go
@@ -0,0 +1,14 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type unexported struct {
+ a int
+ b bool
+}
+
+type Struct struct {
+ unexported
+}
diff --git a/go/test/fixedbugs/issue6789.dir/b.go b/go/test/fixedbugs/issue6789.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..b6a6fc317f53d4895ad1f6ec8d9b2f73dbcd5e98
--- /dev/null
+++ b/go/test/fixedbugs/issue6789.dir/b.go
@@ -0,0 +1,12 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+type s a.Struct
+
+func main() {
+}
diff --git a/go/test/fixedbugs/issue68526.dir/a/a.go b/go/test/fixedbugs/issue68526.dir/a/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..6249eb59df032b621a679d4093a613364d2699e1
--- /dev/null
+++ b/go/test/fixedbugs/issue68526.dir/a/a.go
@@ -0,0 +1,14 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type A[T any] = struct{ F T }
+
+type B = struct{ F int }
+
+func F() B {
+ type a[T any] = struct{ F T }
+ return a[int]{}
+}
diff --git a/go/test/fixedbugs/issue68526.dir/main.go b/go/test/fixedbugs/issue68526.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..8b72ea37b69ebdf010b9ef9c54fcc04edebb2f6d
--- /dev/null
+++ b/go/test/fixedbugs/issue68526.dir/main.go
@@ -0,0 +1,43 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "fmt"
+
+ "issue68526.dir/a"
+)
+
+func main() {
+ unexported()
+ exported()
+}
+
+func unexported() {
+ var want struct{ F int }
+
+ if any(want) != any(a.B{}) || any(want) != any(a.F()) {
+ panic("zero value of alias and concrete type not identical")
+ }
+}
+
+func exported() {
+ var (
+ astr a.A[string]
+ aint a.A[int]
+ )
+
+ if any(astr) != any(struct{ F string }{}) || any(aint) != any(struct{ F int }{}) {
+ panic("zero value of alias and concrete type not identical")
+ }
+
+ if any(astr) == any(aint) {
+ panic("zero value of struct{ F string } and struct{ F int } are not distinct")
+ }
+
+ if got := fmt.Sprintf("%T", astr); got != "struct { F string }" {
+ panic(got)
+ }
+}
diff --git a/go/test/fixedbugs/issue7023.dir/a.go b/go/test/fixedbugs/issue7023.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..cdb54320955b837704264f9f87f88138ab3d89b4
--- /dev/null
+++ b/go/test/fixedbugs/issue7023.dir/a.go
@@ -0,0 +1,10 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func Foo() {
+ goto bar
+bar:
+}
diff --git a/go/test/fixedbugs/issue7023.dir/b.go b/go/test/fixedbugs/issue7023.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..c6fe40dfa27307908672af3f9b2e7128b125cb99
--- /dev/null
+++ b/go/test/fixedbugs/issue7023.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import (
+ "./a"
+)
+
+var f = a.Foo
diff --git a/go/test/fixedbugs/issue74648.dir/a.s b/go/test/fixedbugs/issue74648.dir/a.s
new file mode 100644
index 0000000000000000000000000000000000000000..39a8d7684c4eba8e88ee0948376d2e8eb2f42f39
--- /dev/null
+++ b/go/test/fixedbugs/issue74648.dir/a.s
@@ -0,0 +1,11 @@
+// Copyright 2025 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+TEXT ·F(SB), $0
+ JMP prealigned
+ INT $3 // should never be reached
+prealigned:
+ PCALIGN $0x10
+aligned:
+ RET
diff --git a/go/test/fixedbugs/issue74648.dir/x.go b/go/test/fixedbugs/issue74648.dir/x.go
new file mode 100644
index 0000000000000000000000000000000000000000..afde832d4a593aa72d750c894b6a4e1399d1125f
--- /dev/null
+++ b/go/test/fixedbugs/issue74648.dir/x.go
@@ -0,0 +1,13 @@
+// Copyright 2025 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Issue 74648: wrong jump target when using PCALIGN.
+
+package main
+
+func F()
+
+func main() {
+ F()
+}
diff --git a/go/test/fixedbugs/issue7648.dir/a.go b/go/test/fixedbugs/issue7648.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..c76aaa675f62efd345f5dc4ea1ae5e8503211c36
--- /dev/null
+++ b/go/test/fixedbugs/issue7648.dir/a.go
@@ -0,0 +1,11 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+const (
+ sinPi4 = 0.70710678118654752440084436210484903928483593768847
+ A = complex(sinPi4, -sinPi4)
+)
+
diff --git a/go/test/fixedbugs/issue7648.dir/b.go b/go/test/fixedbugs/issue7648.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..7b336025ae47d8b4846ff5d640849ff36c350b21
--- /dev/null
+++ b/go/test/fixedbugs/issue7648.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func f() {
+ println(a.A)
+}
diff --git a/go/test/fixedbugs/issue7995b.dir/x1.go b/go/test/fixedbugs/issue7995b.dir/x1.go
new file mode 100644
index 0000000000000000000000000000000000000000..bafecf52a9ce0d71db4f0cc9f52aa78a1344da72
--- /dev/null
+++ b/go/test/fixedbugs/issue7995b.dir/x1.go
@@ -0,0 +1,12 @@
+package x1
+
+import "fmt"
+
+var P int
+
+//go:noinline
+func F(x *int) string {
+ P = 50
+ *x = 100
+ return fmt.Sprintln(P, *x)
+}
diff --git a/go/test/fixedbugs/issue7995b.dir/x2.go b/go/test/fixedbugs/issue7995b.dir/x2.go
new file mode 100644
index 0000000000000000000000000000000000000000..eea23eabba2467b032cd48b65dec77edbc3f4564
--- /dev/null
+++ b/go/test/fixedbugs/issue7995b.dir/x2.go
@@ -0,0 +1,10 @@
+package main
+
+import "./x1"
+
+func main() {
+ s := x1.F(&x1.P)
+ if s != "100 100\n" {
+ println("BUG:", s)
+ }
+}
diff --git a/go/test/fixedbugs/issue8060.dir/a.go b/go/test/fixedbugs/issue8060.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..22ba69ee1beda0947fb5e1fffa93d302915c9a13
--- /dev/null
+++ b/go/test/fixedbugs/issue8060.dir/a.go
@@ -0,0 +1,7 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+var A = []*[2][1]float64{}
diff --git a/go/test/fixedbugs/issue8060.dir/b.go b/go/test/fixedbugs/issue8060.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..fc7eb251d0bc1d408b7c7e39434c452eda090f5d
--- /dev/null
+++ b/go/test/fixedbugs/issue8060.dir/b.go
@@ -0,0 +1,13 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+var X = a.A
+
+func b() {
+ _ = [3][1]float64{}
+}
diff --git a/go/test/fixedbugs/issue8280.dir/a.go b/go/test/fixedbugs/issue8280.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..588536e79a630eee74aa695819d38dba46f05681
--- /dev/null
+++ b/go/test/fixedbugs/issue8280.dir/a.go
@@ -0,0 +1,3 @@
+package a
+
+var Bar = func() (_ int) { return 0 }
diff --git a/go/test/fixedbugs/issue8280.dir/b.go b/go/test/fixedbugs/issue8280.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..c46c554588b1a5911ef335c433dd9fdd473b1a2c
--- /dev/null
+++ b/go/test/fixedbugs/issue8280.dir/b.go
@@ -0,0 +1,5 @@
+package b
+
+import "./a"
+
+var foo = a.Bar
diff --git a/go/test/fixedbugs/issue9355.dir/a.go b/go/test/fixedbugs/issue9355.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..84500c8c01117593617d9599b0d7c46d94d4ee1b
--- /dev/null
+++ b/go/test/fixedbugs/issue9355.dir/a.go
@@ -0,0 +1,16 @@
+package main
+
+var x struct {
+ a, b, c int64
+ d struct{ p, q, r int32 }
+ e [8]byte
+ f [4]struct{ p, q, r int32 }
+}
+
+var y = &x.b
+var z = &x.d.q
+
+var b [10]byte
+var c = &b[5]
+
+var w = &x.f[3].r
diff --git a/go/test/fixedbugs/issue9537.dir/a.go b/go/test/fixedbugs/issue9537.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..818c9eb4ab81a45677d50f1d5924df915746ca89
--- /dev/null
+++ b/go/test/fixedbugs/issue9537.dir/a.go
@@ -0,0 +1,25 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type X struct {
+ T [32]byte
+}
+
+func (x *X) Get() []byte {
+ t := x.T
+ return t[:]
+}
+
+func (x *X) RetPtr(i int) *int {
+ i++
+ return &i
+}
+
+func (x *X) RetRPtr(i int) (r1 int, r2 *int) {
+ r1 = i + 1
+ r2 = &r1
+ return
+}
diff --git a/go/test/fixedbugs/issue9537.dir/b.go b/go/test/fixedbugs/issue9537.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..52e64c81f1f6e926e8b350e46c93ef0108ae1c28
--- /dev/null
+++ b/go/test/fixedbugs/issue9537.dir/b.go
@@ -0,0 +1,43 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "bytes"
+
+ "./a"
+)
+
+type X struct {
+ *a.X
+}
+
+type Intf interface {
+ Get() []byte
+ RetPtr(int) *int
+ RetRPtr(int) (int, *int)
+}
+
+func main() {
+ x := &a.X{T: [32]byte{1, 2, 3, 4}}
+ var ix Intf = X{x}
+ t1 := ix.Get()
+ t2 := x.Get()
+ if !bytes.Equal(t1, t2) {
+ panic(t1)
+ }
+
+ p1 := ix.RetPtr(5)
+ p2 := x.RetPtr(7)
+ if *p1 != 6 || *p2 != 8 {
+ panic(*p1)
+ }
+
+ r1, r2 := ix.RetRPtr(10)
+ r3, r4 := x.RetRPtr(13)
+ if r1 != 11 || *r2 != 11 || r3 != 14 || *r4 != 14 {
+ panic("bad RetRPtr")
+ }
+}
diff --git a/go/test/fixedbugs/issue9608.dir/issue9608.go b/go/test/fixedbugs/issue9608.dir/issue9608.go
new file mode 100644
index 0000000000000000000000000000000000000000..ca82ded4cd0d2b4283a8c97c4b807f6d455873a4
--- /dev/null
+++ b/go/test/fixedbugs/issue9608.dir/issue9608.go
@@ -0,0 +1,82 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+func fail() // unimplemented, to test dead code elimination
+
+// Test dead code elimination in if statements
+func init() {
+ if false {
+ fail()
+ }
+ if 0 == 1 {
+ fail()
+ }
+}
+
+// Test dead code elimination in ordinary switch statements
+func init() {
+ const x = 0
+ switch x {
+ case 1:
+ fail()
+ }
+
+ switch 1 {
+ case x:
+ fail()
+ }
+
+ switch {
+ case false:
+ fail()
+ }
+
+ const a = "a"
+ switch a {
+ case "b":
+ fail()
+ }
+
+ const snowman = '☃'
+ switch snowman {
+ case '☀':
+ fail()
+ }
+
+ const zero = float64(0.0)
+ const one = float64(1.0)
+ switch one {
+ case -1.0:
+ fail()
+ case zero:
+ fail()
+ }
+
+ switch 1.0i {
+ case 1:
+ fail()
+ case -1i:
+ fail()
+ }
+
+ const no = false
+ switch no {
+ case true:
+ fail()
+ }
+
+ // Test dead code elimination in large ranges.
+ switch 5 {
+ case 3, 4, 5, 6, 7:
+ case 0, 1, 2:
+ fail()
+ default:
+ fail()
+ }
+}
+
+func main() {
+}
diff --git a/go/test/interface/embed1.dir/embed0.go b/go/test/interface/embed1.dir/embed0.go
new file mode 100644
index 0000000000000000000000000000000000000000..4aed391b634a0069024e686b0af7629bf198a003
--- /dev/null
+++ b/go/test/interface/embed1.dir/embed0.go
@@ -0,0 +1,28 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test that embedded interface types can have local methods.
+
+package p
+
+type T int
+
+func (t T) m() {}
+
+type I interface{ m() }
+type J interface{ I }
+
+func main() {
+ var i I
+ var j J
+ var t T
+ i = t
+ j = t
+ _ = i
+ _ = j
+ i = j
+ _ = i
+ j = i
+ _ = j
+}
diff --git a/go/test/interface/embed1.dir/embed1.go b/go/test/interface/embed1.dir/embed1.go
new file mode 100644
index 0000000000000000000000000000000000000000..7dfb1dbc0ad416533286bfdeb1083b32a067622c
--- /dev/null
+++ b/go/test/interface/embed1.dir/embed1.go
@@ -0,0 +1,43 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test that embedded interface types can have local methods.
+
+package main
+
+import "./embed0"
+
+type T int
+func (t T) m() {}
+
+type I interface { m() }
+type J interface { I }
+
+type PI interface { p.I }
+type PJ interface { p.J }
+
+func main() {
+ var i I
+ var j J
+ var t T
+ i = t
+ j = t
+ _ = i
+ _ = j
+ i = j
+ _ = i
+ j = i
+ _ = j
+ var pi PI
+ var pj PJ
+ var pt p.T
+ pi = pt
+ pj = pt
+ _ = pi
+ _ = pj
+ pi = pj
+ _ = pi
+ pj = pi
+ _ = pj
+}
diff --git a/go/test/interface/embed3.dir/embed0.go b/go/test/interface/embed3.dir/embed0.go
new file mode 100644
index 0000000000000000000000000000000000000000..614609e74aefe73a54795a3ea97e603854b48367
--- /dev/null
+++ b/go/test/interface/embed3.dir/embed0.go
@@ -0,0 +1,21 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+type I1 interface {
+ Foo(int)
+}
+
+type I2 interface {
+ foo(int)
+}
+
+type M1 int
+
+func (M1) foo() {}
+
+type M2 int
+
+func (M2) foo(int) {}
diff --git a/go/test/interface/embed3.dir/embed1.go b/go/test/interface/embed3.dir/embed1.go
new file mode 100644
index 0000000000000000000000000000000000000000..d042482e941c540cd07cf4d05e3c0a3696a9eaec
--- /dev/null
+++ b/go/test/interface/embed3.dir/embed1.go
@@ -0,0 +1,78 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./embed0"
+
+type X1 struct{}
+
+func (X1) Foo() {}
+
+type X2 struct{}
+
+func (X2) foo() {}
+
+type X3 struct{}
+
+func (X3) foo(int) {}
+
+type X4 struct{ p.M1 }
+
+type X5 struct{ p.M1 }
+
+func (X5) foo(int) {}
+
+type X6 struct{ p.M2 }
+
+type X7 struct{ p.M2 }
+
+func (X7) foo() {}
+
+type X8 struct{ p.M2 }
+
+func (X8) foo(int) {}
+
+func main() {
+ var i1 interface{} = X1{}
+ check(func() { _ = i1.(p.I1) }, "interface conversion: main.X1 is not p.I1: missing method Foo")
+
+ var i2 interface{} = X2{}
+ check(func() { _ = i2.(p.I2) }, "interface conversion: main.X2 is not p.I2: missing method foo")
+
+ var i3 interface{} = X3{}
+ check(func() { _ = i3.(p.I2) }, "interface conversion: main.X3 is not p.I2: missing method foo")
+
+ var i4 interface{} = X4{}
+ check(func() { _ = i4.(p.I2) }, "interface conversion: main.X4 is not p.I2: missing method foo")
+
+ var i5 interface{} = X5{}
+ check(func() { _ = i5.(p.I2) }, "interface conversion: main.X5 is not p.I2: missing method foo")
+
+ var i6 interface{} = X6{}
+ check(func() { _ = i6.(p.I2) }, "")
+
+ var i7 interface{} = X7{}
+ check(func() { _ = i7.(p.I2) }, "")
+
+ var i8 interface{} = X8{}
+ check(func() { _ = i8.(p.I2) }, "")
+}
+
+func check(f func(), msg string) {
+ defer func() {
+ v := recover()
+ if v == nil {
+ if msg == "" {
+ return
+ }
+ panic("did not panic")
+ }
+ got := v.(error).Error()
+ if msg != got {
+ panic("want '" + msg + "', got '" + got + "'")
+ }
+ }()
+ f()
+}
diff --git a/go/test/interface/private.dir/private1.go b/go/test/interface/private.dir/private1.go
new file mode 100644
index 0000000000000000000000000000000000000000..75eee51f5a0509c287cc0a7f8682f09c777a0589
--- /dev/null
+++ b/go/test/interface/private.dir/private1.go
@@ -0,0 +1,18 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Imported by private.go, which should not be able to see the private method.
+
+package p
+
+type Exported interface {
+ private()
+}
+
+type Implementation struct{}
+
+func (p *Implementation) private() {}
+
+var X = new(Implementation)
+
diff --git a/go/test/interface/private.dir/prog.go b/go/test/interface/private.dir/prog.go
new file mode 100644
index 0000000000000000000000000000000000000000..abea7d625c762b0f465a7c31d91ef9e3342414fa
--- /dev/null
+++ b/go/test/interface/private.dir/prog.go
@@ -0,0 +1,33 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test that unexported methods are not visible outside the package.
+// Does not compile.
+
+package main
+
+import "./private1"
+
+type Exported interface {
+ private()
+}
+
+type Implementation struct{}
+
+func (p *Implementation) private() {}
+
+func main() {
+ var x Exported
+ x = new(Implementation)
+ x.private()
+
+ var px p.Exported
+ px = p.X
+
+ px.private() // ERROR "private"
+
+ px = new(Implementation) // ERROR "private"
+
+ x = px // ERROR "private"
+}
diff --git a/go/test/interface/recursive1.dir/recursive1.go b/go/test/interface/recursive1.dir/recursive1.go
new file mode 100644
index 0000000000000000000000000000000000000000..8498cb5d7512081a8758dddef699df43801d8c2a
--- /dev/null
+++ b/go/test/interface/recursive1.dir/recursive1.go
@@ -0,0 +1,15 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Mutually recursive type definitions imported and used by recursive1.go.
+
+package p
+
+type I1 interface {
+ F() I2
+}
+
+type I2 interface {
+ I1
+}
diff --git a/go/test/interface/recursive1.dir/recursive2.go b/go/test/interface/recursive1.dir/recursive2.go
new file mode 100644
index 0000000000000000000000000000000000000000..29385df76df17a93b1b459a3e8e18aa2eed7ae75
--- /dev/null
+++ b/go/test/interface/recursive1.dir/recursive2.go
@@ -0,0 +1,20 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test that the mutually recursive types in recursive1.go made it
+// intact and with the same meaning, by assigning to or using them.
+
+package main
+
+import "./recursive1"
+
+func main() {
+ var i1 p.I1
+ var i2 p.I2
+ i1 = i2
+ i2 = i1
+ i1 = i2.F()
+ i2 = i1.F()
+ _, _ = i1, i2
+}
diff --git a/go/test/internal/runtime/sys/README b/go/test/internal/runtime/sys/README
new file mode 100644
index 0000000000000000000000000000000000000000..919e0bb03f45df157c9518fe5853ebd659b8b58e
--- /dev/null
+++ b/go/test/internal/runtime/sys/README
@@ -0,0 +1,7 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+The internal/runtime/sys directory contains tests that specifically need to be
+compiled as-if in the internal/runtime/sys package. For error-check tests,
+these require the additional flags -+ and -p=internal/runtime/sys.
diff --git a/go/test/internal/runtime/sys/inlinegcpc.go b/go/test/internal/runtime/sys/inlinegcpc.go
new file mode 100644
index 0000000000000000000000000000000000000000..7cadc639d101697b5c25af83609a25f0fdcccc4c
--- /dev/null
+++ b/go/test/internal/runtime/sys/inlinegcpc.go
@@ -0,0 +1,29 @@
+// errorcheck -0 -+ -p=internal/runtime/sys -m
+
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sys
+
+// A function that calls sys.GetCallerPC or sys.GetCallerSP
+// cannot be inlined, no matter how small it is.
+
+func GetCallerPC() uintptr
+func GetCallerSP() uintptr
+
+func pc() uintptr {
+ return GetCallerPC() + 1
+}
+
+func cpc() uintptr { // ERROR "can inline cpc"
+ return pc() + 2
+}
+
+func sp() uintptr {
+ return GetCallerSP() + 3
+}
+
+func csp() uintptr { // ERROR "can inline csp"
+ return sp() + 4
+}
diff --git a/go/test/typeparam/issue49241.dir/a.go b/go/test/typeparam/issue49241.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..34c99657d49b9594393b02ba792de821102e8418
--- /dev/null
+++ b/go/test/typeparam/issue49241.dir/a.go
@@ -0,0 +1,13 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type T[P any] struct {
+ x P
+}
+
+type U struct {
+ a,b int
+}
diff --git a/go/test/typeparam/issue49241.dir/b.go b/go/test/typeparam/issue49241.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..e5f1e1290eb8ddd17ccf444e63cae7ba38c44c9a
--- /dev/null
+++ b/go/test/typeparam/issue49241.dir/b.go
@@ -0,0 +1,17 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+//go:noinline
+func F() interface{} {
+ return a.T[int]{}
+}
+
+//go:noinline
+func G() interface{} {
+ return struct{ X, Y a.U }{}
+}
diff --git a/go/test/typeparam/issue49241.dir/c.go b/go/test/typeparam/issue49241.dir/c.go
new file mode 100644
index 0000000000000000000000000000000000000000..34ea7c3ffae86f2c17af762047fcdee613975d66
--- /dev/null
+++ b/go/test/typeparam/issue49241.dir/c.go
@@ -0,0 +1,17 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package c
+
+import "./a"
+
+//go:noinline
+func F() interface{} {
+ return a.T[int]{}
+}
+
+//go:noinline
+func G() interface{} {
+ return struct{ X, Y a.U }{}
+}
diff --git a/go/test/typeparam/issue49241.dir/main.go b/go/test/typeparam/issue49241.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..58bb8a017f16f3882c978e986846593b5dac18ee
--- /dev/null
+++ b/go/test/typeparam/issue49241.dir/main.go
@@ -0,0 +1,21 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./b"
+ "./c"
+)
+
+func main() {
+ if b.G() != c.G() {
+ println(b.G(), c.G())
+ panic("bad")
+ }
+ if b.F() != c.F() {
+ println(b.F(), c.F())
+ panic("bad")
+ }
+}
diff --git a/go/test/typeparam/issue49246.dir/a.go b/go/test/typeparam/issue49246.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..97459ee7481de590169e3453c77399aa1f4807b1
--- /dev/null
+++ b/go/test/typeparam/issue49246.dir/a.go
@@ -0,0 +1,20 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type R[T any] struct{ v T }
+
+func (r R[T]) Self() R[T] { return R[T]{} }
+
+type Fn[T any] func() R[T]
+
+func X() (r R[int]) { return r.Self() }
+
+func Y[T any](a Fn[T]) Fn[int] {
+ return func() (r R[int]) {
+ // No crash: return R[int]{}
+ return r.Self()
+ }
+}
diff --git a/go/test/typeparam/issue49246.dir/b.go b/go/test/typeparam/issue49246.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..5141b72fd4ddceb5d2ec320481bec4e7f95546fb
--- /dev/null
+++ b/go/test/typeparam/issue49246.dir/b.go
@@ -0,0 +1,9 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func Crash() { a.Y(a.X)() }
diff --git a/go/test/typeparam/issue49497.dir/a.go b/go/test/typeparam/issue49497.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..86062d446ffff60a62f53625b1b287919a2638bb
--- /dev/null
+++ b/go/test/typeparam/issue49497.dir/a.go
@@ -0,0 +1,26 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func F[T any]() A[T] {
+ var x A[T]
+ return x
+}
+
+type A[T any] struct {
+ b B[T]
+}
+
+func (a A[T]) M() C[T] {
+ return C[T]{
+ B: a.b,
+ }
+}
+
+type B[T any] struct{}
+
+type C[T any] struct {
+ B B[T]
+}
diff --git a/go/test/typeparam/issue49497.dir/main.go b/go/test/typeparam/issue49497.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..e74dae08598ced8e8b1d8eeba9bd082b5bc4a520
--- /dev/null
+++ b/go/test/typeparam/issue49497.dir/main.go
@@ -0,0 +1,11 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+func main() {
+ a.F[string]()
+}
diff --git a/go/test/typeparam/issue49524.dir/a.go b/go/test/typeparam/issue49524.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..f40075e953ee6ae0b15f7f2492169ec43c1996b8
--- /dev/null
+++ b/go/test/typeparam/issue49524.dir/a.go
@@ -0,0 +1,8 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func F[T any]() {
+}
diff --git a/go/test/typeparam/issue49524.dir/main.go b/go/test/typeparam/issue49524.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..8787e7ea69b365137ef2964dd460333eb208ec0c
--- /dev/null
+++ b/go/test/typeparam/issue49524.dir/main.go
@@ -0,0 +1,11 @@
+package main
+
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+import "./a"
+
+func main() {
+ a.F[int]()
+}
diff --git a/go/test/typeparam/issue49536.dir/a.go b/go/test/typeparam/issue49536.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..a95ad60812cbaa3683174fb6fdefa0606e9547a1
--- /dev/null
+++ b/go/test/typeparam/issue49536.dir/a.go
@@ -0,0 +1,12 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func F() interface{} { return new(T[int]) }
+
+type T[P any] int
+
+func (x *T[P]) One() int { return x.Two() }
+func (x *T[P]) Two() int { return 0 }
diff --git a/go/test/typeparam/issue49536.dir/b.go b/go/test/typeparam/issue49536.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..b08a77b9de1c2d64d6ac1958ecc588e2f6237716
--- /dev/null
+++ b/go/test/typeparam/issue49536.dir/b.go
@@ -0,0 +1,9 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+var _ = a.F()
diff --git a/go/test/typeparam/issue49659.dir/a.go b/go/test/typeparam/issue49659.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..718bc0c5fce5d7dbd7c305e082a9280b0a780338
--- /dev/null
+++ b/go/test/typeparam/issue49659.dir/a.go
@@ -0,0 +1,13 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type A[T any] struct {
+ a int
+}
+
+func (a A[T]) F() {
+ _ = &a.a
+}
diff --git a/go/test/typeparam/issue49659.dir/b.go b/go/test/typeparam/issue49659.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..4818a42a486f373e6cf863fdd4bea25aee9e0cf4
--- /dev/null
+++ b/go/test/typeparam/issue49659.dir/b.go
@@ -0,0 +1,15 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+type B[T any] struct {
+ v a.A[T]
+}
+
+func (b B[T]) F() {
+ b.v.F()
+}
diff --git a/go/test/typeparam/issue49667.dir/a.go b/go/test/typeparam/issue49667.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..3b1889f699272da8af5b7cd06a29fe589f7e5cef
--- /dev/null
+++ b/go/test/typeparam/issue49667.dir/a.go
@@ -0,0 +1,12 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type A[T any] struct {
+}
+
+func (a A[T]) F() {
+ _ = a
+}
diff --git a/go/test/typeparam/issue49667.dir/b.go b/go/test/typeparam/issue49667.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..81cdb80036dc14ce87cf0988bb10015aabcee68c
--- /dev/null
+++ b/go/test/typeparam/issue49667.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+type B[T any] struct {
+ _ a.A[T]
+}
diff --git a/go/test/typeparam/issue49667.dir/main.go b/go/test/typeparam/issue49667.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..f9fa60f3f533a0a952cd7ff22f3efce8b59861ca
--- /dev/null
+++ b/go/test/typeparam/issue49667.dir/main.go
@@ -0,0 +1,11 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./b"
+
+func main() {
+ var _ b.B[int]
+}
diff --git a/go/test/typeparam/issue49893.dir/a.go b/go/test/typeparam/issue49893.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..bc810cd3dd5300752cd3b36322aecc983b68c245
--- /dev/null
+++ b/go/test/typeparam/issue49893.dir/a.go
@@ -0,0 +1,15 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type Option[T any] interface {
+ ToSeq() Seq[T]
+}
+
+type Seq[T any] []T
+
+func (r Seq[T]) Find(p func(v T) bool) Option[T] {
+ panic("")
+}
diff --git a/go/test/typeparam/issue49893.dir/b.go b/go/test/typeparam/issue49893.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..b86b53666489149a7c31a1e60adc0d96e96644cd
--- /dev/null
+++ b/go/test/typeparam/issue49893.dir/b.go
@@ -0,0 +1,15 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+type Ap1[A, B any] struct {
+ opt a.Option[A]
+}
+
+type Ap2[A, B any] struct {
+ opt a.Option[A]
+}
diff --git a/go/test/typeparam/issue49893.dir/main.go b/go/test/typeparam/issue49893.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..447212d027648f1fee31e1fe35c823f16f04a6ae
--- /dev/null
+++ b/go/test/typeparam/issue49893.dir/main.go
@@ -0,0 +1,15 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./b"
+ "fmt"
+)
+
+func main() {
+ opt := b.Ap1[string, string]{}
+ fmt.Println(opt)
+}
diff --git a/go/test/typeparam/issue50121.dir/a.go b/go/test/typeparam/issue50121.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..ca11b6b27a2d1a6dc3eafb188b3dd4335bf6bfa1
--- /dev/null
+++ b/go/test/typeparam/issue50121.dir/a.go
@@ -0,0 +1,26 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+import (
+ "math/rand"
+)
+
+type Integer interface {
+ ~int | ~int8 | ~int16 | ~int32 | ~int64 |
+ ~uint | ~uint8 | ~uint16 | ~uint32 | ~uint64 | ~uintptr
+}
+
+type Builder[T Integer] struct{}
+
+func (r Builder[T]) New() T {
+ return T(rand.Int())
+}
+
+var IntBuilder = Builder[int]{}
+
+func BuildInt() int {
+ return IntBuilder.New()
+}
diff --git a/go/test/typeparam/issue50121.dir/main.go b/go/test/typeparam/issue50121.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..3978ef4fba8353eb58201a769ab2aa1909a73613
--- /dev/null
+++ b/go/test/typeparam/issue50121.dir/main.go
@@ -0,0 +1,18 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./a"
+)
+
+//go:noinline
+func BuildInt() int {
+ return a.BuildInt()
+}
+
+func main() {
+ BuildInt()
+}
diff --git a/go/test/typeparam/issue50121b.dir/a.go b/go/test/typeparam/issue50121b.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..4ddbb6ea847765f0b8d3dd1a990a1dff3f950280
--- /dev/null
+++ b/go/test/typeparam/issue50121b.dir/a.go
@@ -0,0 +1,16 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type Integer interface {
+ ~int | ~int8 | ~int16 | ~int32 | ~int64 |
+ ~uint | ~uint8 | ~uint16 | ~uint32 | ~uint64 | ~uintptr
+}
+
+type Builder[T Integer] struct{}
+
+func (r Builder[T]) New() T {
+ return T(42)
+}
diff --git a/go/test/typeparam/issue50121b.dir/b.go b/go/test/typeparam/issue50121b.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..efa6cbbc307e378bc66d8a6dc6b3c70aa22d12ac
--- /dev/null
+++ b/go/test/typeparam/issue50121b.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import (
+ "./a"
+)
+
+var IntBuilder = a.Builder[int]{}
diff --git a/go/test/typeparam/issue50121b.dir/c.go b/go/test/typeparam/issue50121b.dir/c.go
new file mode 100644
index 0000000000000000000000000000000000000000..169135678dad1ec1600523268d5337fd7798019e
--- /dev/null
+++ b/go/test/typeparam/issue50121b.dir/c.go
@@ -0,0 +1,13 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package c
+
+import (
+ "./b"
+)
+
+func BuildInt() int {
+ return b.IntBuilder.New()
+}
diff --git a/go/test/typeparam/issue50121b.dir/d.go b/go/test/typeparam/issue50121b.dir/d.go
new file mode 100644
index 0000000000000000000000000000000000000000..93b40c921e04a77240a8a8cc07518c4a46edc623
--- /dev/null
+++ b/go/test/typeparam/issue50121b.dir/d.go
@@ -0,0 +1,13 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package d
+
+import (
+ "./c"
+)
+
+func BuildInt() int {
+ return c.BuildInt()
+}
diff --git a/go/test/typeparam/issue50121b.dir/main.go b/go/test/typeparam/issue50121b.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..33986018506d5964c51617bbe142051daf21e90f
--- /dev/null
+++ b/go/test/typeparam/issue50121b.dir/main.go
@@ -0,0 +1,12 @@
+package main
+
+import (
+ "./d"
+ "fmt"
+)
+
+func main() {
+ if got, want := d.BuildInt(), 42; got != want {
+ panic(fmt.Sprintf("got %d, want %d", got, want))
+ }
+}
diff --git a/go/test/typeparam/issue50437.dir/a.go b/go/test/typeparam/issue50437.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..4a136b52ae2d00539ac5aa587d5bc2839bdbb9a5
--- /dev/null
+++ b/go/test/typeparam/issue50437.dir/a.go
@@ -0,0 +1,43 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type MarshalOptions struct {
+ *typedArshalers[MarshalOptions]
+}
+
+func Marshal(in interface{}) (out []byte, err error) {
+ return MarshalOptions{}.Marshal(in)
+}
+
+func (mo MarshalOptions) Marshal(in interface{}) (out []byte, err error) {
+ err = mo.MarshalNext(in)
+ return nil, err
+}
+
+func (mo MarshalOptions) MarshalNext(in interface{}) error {
+ a := new(arshaler)
+ a.marshal = func(MarshalOptions) error { return nil }
+ return a.marshal(mo)
+}
+
+type arshaler struct {
+ marshal func(MarshalOptions) error
+}
+
+type typedArshalers[Options any] struct {
+ m M
+}
+
+func (a *typedArshalers[Options]) lookup(fnc func(Options) error) (func(Options) error, bool) {
+ a.m.Load(nil)
+ return fnc, false
+}
+
+type M struct {}
+
+func (m *M) Load(key any) (value any, ok bool) {
+ return
+}
diff --git a/go/test/typeparam/issue50437.dir/b.go b/go/test/typeparam/issue50437.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..afddc3f3307493bbc47b47af165c95d9189f455c
--- /dev/null
+++ b/go/test/typeparam/issue50437.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func f() {
+ a.Marshal(map[int]int{})
+}
diff --git a/go/test/typeparam/issue50481b.dir/b.go b/go/test/typeparam/issue50481b.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..d458357c51f2f670ca86e4dad258ec600e95d120
--- /dev/null
+++ b/go/test/typeparam/issue50481b.dir/b.go
@@ -0,0 +1,16 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "fmt"
+
+type Foo[T1 ~string, T2 ~int] struct {
+ ValueA T1
+ ValueB T2
+}
+
+func (f *Foo[_, _]) String() string {
+ return fmt.Sprintf("%v %v", f.ValueA, f.ValueB)
+}
diff --git a/go/test/typeparam/issue50481b.dir/main.go b/go/test/typeparam/issue50481b.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..6a5067c9fb2d862fd09c5a4c2106aeab39e47189
--- /dev/null
+++ b/go/test/typeparam/issue50481b.dir/main.go
@@ -0,0 +1,23 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test that type substitution and export/import works correctly even for a method of
+// a generic type that has multiple blank type params.
+
+package main
+
+import (
+ "./b"
+ "fmt"
+)
+
+func main() {
+ foo := &b.Foo[string, int]{
+ ValueA: "i am a string",
+ ValueB: 123,
+ }
+ if got, want := fmt.Sprintln(foo), "i am a string 123\n"; got != want {
+ panic(fmt.Sprintf("got %s, want %s", got, want))
+ }
+}
diff --git a/go/test/typeparam/issue50481c.dir/a.go b/go/test/typeparam/issue50481c.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..384ba23f989ed0a1a11c4b77d9a99869256fda0a
--- /dev/null
+++ b/go/test/typeparam/issue50481c.dir/a.go
@@ -0,0 +1,30 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type A interface {
+ int | int64
+}
+
+type B interface {
+ string
+}
+
+type C interface {
+ String() string
+}
+
+type Myint int
+
+func (i Myint) String() string {
+ return "aa"
+}
+
+type T[P A, _ C, _ B] int
+
+func (v T[P, Q, R]) test() {
+ var r Q
+ r.String()
+}
diff --git a/go/test/typeparam/issue50481c.dir/main.go b/go/test/typeparam/issue50481c.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..178542bc380eb3657ffd39d59033d587c5824a33
--- /dev/null
+++ b/go/test/typeparam/issue50481c.dir/main.go
@@ -0,0 +1,18 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test that type substitution works and export/import works correctly even for a
+// generic type that has multiple blank type params.
+
+package main
+
+import (
+ "./a"
+ "fmt"
+)
+
+func main() {
+ var x a.T[int, a.Myint, string]
+ fmt.Printf("%v\n", x)
+}
diff --git a/go/test/typeparam/issue50485.dir/a.go b/go/test/typeparam/issue50485.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..97cf4d254951a29988d715bec1af8787923943b0
--- /dev/null
+++ b/go/test/typeparam/issue50485.dir/a.go
@@ -0,0 +1,238 @@
+package a
+
+import "fmt"
+
+type ImplicitOrd interface {
+ ~int | ~int8 | ~int16 | ~int32 | ~int64 |
+ ~uint | ~uint8 | ~uint16 | ~uint32 | ~uint64 | ~uintptr |
+ ~float32 | ~float64 |
+ ~string
+}
+
+func LessGiven[T ImplicitOrd]() Ord[T] {
+ return LessFunc[T](func(a, b T) bool {
+ return a < b
+ })
+}
+
+type Eq[T any] interface {
+ Eqv(a T, b T) bool
+}
+
+type Ord[T any] interface {
+ Eq[T]
+ Less(a T, b T) bool
+}
+
+type LessFunc[T any] func(a, b T) bool
+
+func (r LessFunc[T]) Eqv(a, b T) bool {
+ return r(a, b) == false && r(b, a) == false
+}
+
+func (r LessFunc[T]) Less(a, b T) bool {
+ return r(a, b)
+}
+
+type Option[T any] struct {
+ v *T
+}
+
+func (r Option[T]) IsDefined() bool {
+ return r.v != nil
+}
+
+func (r Option[T]) IsEmpty() bool {
+ return !r.IsDefined()
+}
+
+func (r Option[T]) Get() T {
+ return *r.v
+}
+
+func (r Option[T]) String() string {
+ if r.IsDefined() {
+ return fmt.Sprintf("Some(%v)", r.v)
+ } else {
+ return "None"
+ }
+}
+
+func (r Option[T]) OrElse(t T) T {
+ if r.IsDefined() {
+ return *r.v
+ }
+ return t
+}
+
+func (r Option[T]) Recover(f func() T) Option[T] {
+ if r.IsDefined() {
+ return r
+ }
+ t := f()
+ return Option[T]{&t}
+}
+
+type Func1[A1, R any] func(a1 A1) R
+
+type Func2[A1, A2, R any] func(a1 A1, a2 A2) R
+
+func (r Func2[A1, A2, R]) Curried() Func1[A1, Func1[A2, R]] {
+ return func(a1 A1) Func1[A2, R] {
+ return Func1[A2, R](func(a2 A2) R {
+ return r(a1, a2)
+ })
+ }
+}
+
+type HList interface {
+ sealed()
+}
+
+// Header is constrains interface type, enforce Head type of Cons is HT
+type Header[HT any] interface {
+ HList
+ Head() HT
+}
+
+// Cons means H :: T
+// zero value of Cons[H,T] is not allowed.
+// so Cons defined as interface type
+type Cons[H any, T HList] interface {
+ HList
+ Head() H
+ Tail() T
+}
+
+type Nil struct {
+}
+
+func (r Nil) Head() Nil {
+ return r
+}
+
+func (r Nil) Tail() Nil {
+ return r
+}
+
+func (r Nil) String() string {
+ return "Nil"
+}
+
+func (r Nil) sealed() {
+
+}
+
+type hlistImpl[H any, T HList] struct {
+ head H
+ tail T
+}
+
+func (r hlistImpl[H, T]) Head() H {
+ return r.head
+}
+
+func (r hlistImpl[H, T]) Tail() T {
+ return r.tail
+}
+
+func (r hlistImpl[H, T]) String() string {
+ return fmt.Sprintf("%v :: %v", r.head, r.tail)
+}
+
+func (r hlistImpl[H, T]) sealed() {
+
+}
+
+func hlist[H any, T HList](h H, t T) Cons[H, T] {
+ return hlistImpl[H, T]{h, t}
+}
+
+func Concat[H any, T HList](h H, t T) Cons[H, T] {
+ return hlist(h, t)
+}
+
+func Empty() Nil {
+ return Nil{}
+}
+func Some[T any](v T) Option[T] {
+ return Option[T]{}.Recover(func() T {
+ return v
+ })
+}
+
+func None[T any]() Option[T] {
+ return Option[T]{}
+}
+
+func Ap[T, U any](t Option[Func1[T, U]], a Option[T]) Option[U] {
+ return FlatMap(t, func(f Func1[T, U]) Option[U] {
+ return Map(a, f)
+ })
+}
+
+func Map[T, U any](opt Option[T], f func(v T) U) Option[U] {
+ return FlatMap(opt, func(v T) Option[U] {
+ return Some(f(v))
+ })
+}
+
+func FlatMap[T, U any](opt Option[T], fn func(v T) Option[U]) Option[U] {
+ if opt.IsDefined() {
+ return fn(opt.Get())
+ }
+ return None[U]()
+}
+
+type ApplicativeFunctor1[H Header[HT], HT, A, R any] struct {
+ h Option[H]
+ fn Option[Func1[A, R]]
+}
+
+func (r ApplicativeFunctor1[H, HT, A, R]) ApOption(a Option[A]) Option[R] {
+ return Ap(r.fn, a)
+}
+
+func (r ApplicativeFunctor1[H, HT, A, R]) Ap(a A) Option[R] {
+ return r.ApOption(Some(a))
+}
+
+func Applicative1[A, R any](fn Func1[A, R]) ApplicativeFunctor1[Nil, Nil, A, R] {
+ return ApplicativeFunctor1[Nil, Nil, A, R]{Some(Empty()), Some(fn)}
+}
+
+type ApplicativeFunctor2[H Header[HT], HT, A1, A2, R any] struct {
+ h Option[H]
+ fn Option[Func1[A1, Func1[A2, R]]]
+}
+
+func (r ApplicativeFunctor2[H, HT, A1, A2, R]) ApOption(a Option[A1]) ApplicativeFunctor1[Cons[A1, H], A1, A2, R] {
+
+ nh := FlatMap(r.h, func(hv H) Option[Cons[A1, H]] {
+ return Map(a, func(av A1) Cons[A1, H] {
+ return Concat(av, hv)
+ })
+ })
+
+ return ApplicativeFunctor1[Cons[A1, H], A1, A2, R]{nh, Ap(r.fn, a)}
+}
+func (r ApplicativeFunctor2[H, HT, A1, A2, R]) Ap(a A1) ApplicativeFunctor1[Cons[A1, H], A1, A2, R] {
+
+ return r.ApOption(Some(a))
+}
+
+func Applicative2[A1, A2, R any](fn Func2[A1, A2, R]) ApplicativeFunctor2[Nil, Nil, A1, A2, R] {
+ return ApplicativeFunctor2[Nil, Nil, A1, A2, R]{Some(Empty()), Some(fn.Curried())}
+}
+func OrdOption[T any](m Ord[T]) Ord[Option[T]] {
+ return LessFunc[Option[T]](func(t1 Option[T], t2 Option[T]) bool {
+ if !t1.IsDefined() && !t2.IsDefined() {
+ return false
+ }
+ return Applicative2(m.Less).ApOption(t1).ApOption(t2).OrElse(!t1.IsDefined())
+ })
+}
+
+func Given[T ImplicitOrd]() Ord[T] {
+ return LessGiven[T]()
+}
diff --git a/go/test/typeparam/issue50485.dir/main.go b/go/test/typeparam/issue50485.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..7181b937fd6c0ef3676f2e9b1d7e3c42c98a9cda
--- /dev/null
+++ b/go/test/typeparam/issue50485.dir/main.go
@@ -0,0 +1,9 @@
+package main
+
+import (
+ "./a"
+)
+
+func main() {
+ _ = a.OrdOption(a.Given[int]())
+}
diff --git a/go/test/typeparam/issue50486.dir/goerror_fp.go b/go/test/typeparam/issue50486.dir/goerror_fp.go
new file mode 100644
index 0000000000000000000000000000000000000000..fec9095f79678f6cb6f91c7fe06d62b84f72c948
--- /dev/null
+++ b/go/test/typeparam/issue50486.dir/goerror_fp.go
@@ -0,0 +1,75 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package goerror_fp
+
+type Seq[T any] []T
+
+func (r Seq[T]) Size() int {
+ return len(r)
+}
+
+func (r Seq[T]) Append(items ...T) Seq[T] {
+ tail := Seq[T](items)
+ ret := make(Seq[T], r.Size()+tail.Size())
+
+ for i := range r {
+ ret[i] = r[i]
+ }
+
+ for i := range tail {
+ ret[i+r.Size()] = tail[i]
+ }
+
+ return ret
+}
+
+func (r Seq[T]) Iterator() Iterator[T] {
+ idx := 0
+
+ return Iterator[T]{
+ IsHasNext: func() bool {
+ return idx < r.Size()
+ },
+ GetNext: func() T {
+ ret := r[idx]
+ idx++
+ return ret
+ },
+ }
+}
+
+type Iterator[T any] struct {
+ IsHasNext func() bool
+ GetNext func() T
+}
+
+func (r Iterator[T]) ToSeq() Seq[T] {
+ ret := Seq[T]{}
+ for r.HasNext() {
+ ret = append(ret, r.Next())
+ }
+ return ret
+}
+
+func (r Iterator[T]) Map(f func(T) any) Iterator[any] {
+ return MakeIterator(r.HasNext, func() any {
+ return f(r.Next())
+ })
+}
+
+func (r Iterator[T]) HasNext() bool {
+ return r.IsHasNext()
+}
+
+func (r Iterator[T]) Next() T {
+ return r.GetNext()
+}
+
+func MakeIterator[T any](has func() bool, next func() T) Iterator[T] {
+ return Iterator[T]{
+ IsHasNext: has,
+ GetNext: next,
+ }
+}
diff --git a/go/test/typeparam/issue50486.dir/main.go b/go/test/typeparam/issue50486.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..c2c8eea73d7bcc9c2dad20945043caafa25e2d3c
--- /dev/null
+++ b/go/test/typeparam/issue50486.dir/main.go
@@ -0,0 +1,16 @@
+package main
+
+import fp "./goerror_fp"
+
+func Fold[A, B any](zero B, a A, f func(B, A) B) B {
+ return f(zero, a)
+}
+
+func main() {
+
+ var v any = "hello"
+ Fold(fp.Seq[any]{}, v, func(seq fp.Seq[any], v any) fp.Seq[any] {
+ return seq.Append(v)
+ })
+
+}
diff --git a/go/test/typeparam/issue50552.dir/a.go b/go/test/typeparam/issue50552.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..89b9bcb87775ea5888ede70fadd1f39bbb24f315
--- /dev/null
+++ b/go/test/typeparam/issue50552.dir/a.go
@@ -0,0 +1,16 @@
+package a
+
+type Builder[T any] struct{}
+
+func (r Builder[T]) New() T {
+ var v T
+ return v
+}
+
+func (r Builder[T]) New2() T {
+ return r.New()
+}
+
+func BuildInt() int {
+ return Builder[int]{}.New()
+}
diff --git a/go/test/typeparam/issue50552.dir/main.go b/go/test/typeparam/issue50552.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..0ff2ed360877ac251ab957ba77b5beb6973e0c1a
--- /dev/null
+++ b/go/test/typeparam/issue50552.dir/main.go
@@ -0,0 +1,20 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./a"
+ "fmt"
+)
+
+func BuildInt() int {
+ return a.BuildInt()
+}
+
+func main() {
+ if got, want := BuildInt(), 0; got != want {
+ panic(fmt.Sprintf("got %d, want %d", got, want))
+ }
+}
diff --git a/go/test/typeparam/issue50561.dir/diameter.go b/go/test/typeparam/issue50561.dir/diameter.go
new file mode 100644
index 0000000000000000000000000000000000000000..2bfe92405da520ff78bc5ef3925269ab90d7296f
--- /dev/null
+++ b/go/test/typeparam/issue50561.dir/diameter.go
@@ -0,0 +1,86 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package diameter
+
+type Runnable interface {
+ Run()
+}
+
+// RunnableFunc is converter which converts function to Runnable interface
+type RunnableFunc func()
+
+// Run is Runnable.Run
+func (r RunnableFunc) Run() {
+ r()
+}
+
+type Executor interface {
+ ExecuteUnsafe(runnable Runnable)
+}
+
+type Promise[T any] interface {
+ Future() Future[T]
+ Success(value T) bool
+ Failure(err error) bool
+ IsCompleted() bool
+ Complete(result Try[T]) bool
+}
+
+type Future[T any] interface {
+ OnFailure(cb func(err error), ctx ...Executor)
+ OnSuccess(cb func(success T), ctx ...Executor)
+ Foreach(f func(v T), ctx ...Executor)
+ OnComplete(cb func(try Try[T]), ctx ...Executor)
+ IsCompleted() bool
+ // Value() Option[Try[T]]
+ Failed() Future[error]
+ Recover(f func(err error) T, ctx ...Executor) Future[T]
+ RecoverWith(f func(err error) Future[T], ctx ...Executor) Future[T]
+}
+
+type Try[T any] struct {
+ v *T
+ err error
+}
+
+func (r Try[T]) IsSuccess() bool {
+ return r.v != nil
+}
+
+type ByteBuffer struct {
+ pos int
+ buf []byte
+ underflow error
+}
+
+// InboundHandler is extends of uclient.NetInboundHandler
+type InboundHandler interface {
+ OriginHost() string
+ OriginRealm() string
+}
+
+type transactionID struct {
+ hopID uint32
+ endID uint32
+}
+
+type roundTripper struct {
+ promise map[transactionID]Promise[*ByteBuffer]
+ host string
+ realm string
+}
+
+func (r *roundTripper) OriginHost() string {
+ return r.host
+}
+func (r *roundTripper) OriginRealm() string {
+ return r.realm
+}
+
+func NewInboundHandler(host string, realm string, productName string) InboundHandler {
+ ret := &roundTripper{promise: make(map[transactionID]Promise[*ByteBuffer]), host: host, realm: realm}
+
+ return ret
+}
diff --git a/go/test/typeparam/issue50561.dir/main.go b/go/test/typeparam/issue50561.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..3e656bde32dc81d1045700e2bb06fdc66e5190d5
--- /dev/null
+++ b/go/test/typeparam/issue50561.dir/main.go
@@ -0,0 +1,13 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./diameter"
+)
+
+func main() {
+ diameter.NewInboundHandler("hello", "world", "hi")
+}
diff --git a/go/test/typeparam/issue50598.dir/a0.go b/go/test/typeparam/issue50598.dir/a0.go
new file mode 100644
index 0000000000000000000000000000000000000000..61d353e462cd69fb821403344c5a97afe9bc87db
--- /dev/null
+++ b/go/test/typeparam/issue50598.dir/a0.go
@@ -0,0 +1,23 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a0
+
+type Builder[T any] struct{}
+
+func (r Builder[T]) New1() T {
+ var v T
+ return v
+}
+
+func (r Builder[T]) New2() T {
+ var v T
+ return v
+}
+
+type IntBuilder struct{}
+
+func (b IntBuilder) New() int {
+ return Builder[int]{}.New2()
+}
diff --git a/go/test/typeparam/issue50598.dir/a1.go b/go/test/typeparam/issue50598.dir/a1.go
new file mode 100644
index 0000000000000000000000000000000000000000..36624b4bd67ac876b793c513eae0b16d709c8e15
--- /dev/null
+++ b/go/test/typeparam/issue50598.dir/a1.go
@@ -0,0 +1,11 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a1
+
+import "./a0"
+
+func New() int {
+ return a0.IntBuilder{}.New()
+}
diff --git a/go/test/typeparam/issue50598.dir/a2.go b/go/test/typeparam/issue50598.dir/a2.go
new file mode 100644
index 0000000000000000000000000000000000000000..c28be66f6bab288ff603c5eb355b38f0f829d43d
--- /dev/null
+++ b/go/test/typeparam/issue50598.dir/a2.go
@@ -0,0 +1,11 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a2
+
+import "./a0"
+
+func New() int {
+ return a0.Builder[int]{}.New1()
+}
diff --git a/go/test/typeparam/issue50598.dir/main.go b/go/test/typeparam/issue50598.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..b0b6844ccc2858ea6182a208f5b39f8a56ff353f
--- /dev/null
+++ b/go/test/typeparam/issue50598.dir/main.go
@@ -0,0 +1,22 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "fmt"
+
+ "./a1"
+ "./a2"
+)
+
+func New() int {
+ return a1.New() + a2.New()
+}
+
+func main() {
+ if got, want := New(), 0; got != want {
+ panic(fmt.Sprintf("got %d, want %d", got, want))
+ }
+}
diff --git a/go/test/typeparam/issue50841.dir/a.go b/go/test/typeparam/issue50841.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..37e023370187e345e031ffba266425ac03c94801
--- /dev/null
+++ b/go/test/typeparam/issue50841.dir/a.go
@@ -0,0 +1,22 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func Marshal[foobar any]() {
+ _ = NewEncoder[foobar]()
+}
+
+func NewEncoder[foobar any]() *Encoder[foobar] {
+ return nil
+}
+
+type Encoder[foobar any] struct {
+}
+
+func (e *Encoder[foobar]) EncodeToken(t Token[foobar]) {
+
+}
+
+type Token[foobar any] any
diff --git a/go/test/typeparam/issue50841.dir/b.go b/go/test/typeparam/issue50841.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..38e3de3a6bb6aa8970b787da3ab3c9d6b56272b0
--- /dev/null
+++ b/go/test/typeparam/issue50841.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func F() {
+ a.Marshal[int]()
+}
diff --git a/go/test/typeparam/issue51219.dir/a.go b/go/test/typeparam/issue51219.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..29670df0d3a764eddd6a8fd293aa022bb27c736d
--- /dev/null
+++ b/go/test/typeparam/issue51219.dir/a.go
@@ -0,0 +1,20 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+// Type I is the first basic test for the issue, which relates to a type that is recursive
+// via a type constraint. (In this test, I -> IConstraint -> MyStruct -> I.)
+type JsonRaw []byte
+
+type MyStruct struct {
+ x *I[JsonRaw]
+}
+
+type IConstraint interface {
+ JsonRaw | MyStruct
+}
+
+type I[T IConstraint] struct {
+}
diff --git a/go/test/typeparam/issue51219.dir/main.go b/go/test/typeparam/issue51219.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..14c6d179d2b38e32454840da1281c8a7d3252909
--- /dev/null
+++ b/go/test/typeparam/issue51219.dir/main.go
@@ -0,0 +1,16 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./a"
+ "fmt"
+)
+
+func main() {
+ var x a.I[a.JsonRaw]
+
+ fmt.Printf("%v\n", x)
+}
diff --git a/go/test/typeparam/issue51219b.dir/a.go b/go/test/typeparam/issue51219b.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..19049406a6d9e978ed683ae301675372c60641c3
--- /dev/null
+++ b/go/test/typeparam/issue51219b.dir/a.go
@@ -0,0 +1,37 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type Interaction[DataT InteractionDataConstraint] struct {
+}
+
+type InteractionDataConstraint interface {
+ []byte |
+ UserCommandInteractionData
+}
+
+type UserCommandInteractionData struct {
+ resolvedInteractionWithOptions
+}
+
+type resolvedInteractionWithOptions struct {
+ Resolved Resolved `json:"resolved,omitempty"`
+}
+
+type Resolved struct {
+ Users ResolvedData[User] `json:"users,omitempty"`
+}
+
+type ResolvedData[T ResolvedDataConstraint] map[uint64]T
+
+type ResolvedDataConstraint interface {
+ User | Message
+}
+
+type User struct{}
+
+type Message struct {
+ Interaction *Interaction[[]byte] `json:"interaction,omitempty"`
+}
diff --git a/go/test/typeparam/issue51219b.dir/b.go b/go/test/typeparam/issue51219b.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..8413d666b7e2cd9fce155d9aeedc8897a5443dc2
--- /dev/null
+++ b/go/test/typeparam/issue51219b.dir/b.go
@@ -0,0 +1,14 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import (
+ "./a"
+)
+
+// InteractionRequest is an incoming request Interaction
+type InteractionRequest[T a.InteractionDataConstraint] struct {
+ a.Interaction[T]
+}
diff --git a/go/test/typeparam/issue51219b.dir/p.go b/go/test/typeparam/issue51219b.dir/p.go
new file mode 100644
index 0000000000000000000000000000000000000000..9f8b840d48b1b748e0771ffedca213bbf83e9219
--- /dev/null
+++ b/go/test/typeparam/issue51219b.dir/p.go
@@ -0,0 +1,14 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+import (
+ "./b"
+)
+
+// ResponseWriterMock mocks corde's ResponseWriter interface
+type ResponseWriterMock struct {
+ x b.InteractionRequest[[]byte]
+}
diff --git a/go/test/typeparam/issue51250a.dir/a.go b/go/test/typeparam/issue51250a.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..12dd60a3d16b51630c20805168a77a04908dcfb2
--- /dev/null
+++ b/go/test/typeparam/issue51250a.dir/a.go
@@ -0,0 +1,9 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type G[T any] struct {
+ x T
+}
diff --git a/go/test/typeparam/issue51250a.dir/b.go b/go/test/typeparam/issue51250a.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..114c9f80f702f42f04b3e837c592c136465a2ae6
--- /dev/null
+++ b/go/test/typeparam/issue51250a.dir/b.go
@@ -0,0 +1,24 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+type T struct { a int }
+
+var I interface{} = a.G[T]{}
+
+//go:noinline
+func F(x interface{}) {
+ switch x.(type) {
+ case a.G[T]:
+ case int:
+ panic("bad")
+ case float64:
+ panic("bad")
+ default:
+ panic("bad")
+ }
+}
diff --git a/go/test/typeparam/issue51250a.dir/main.go b/go/test/typeparam/issue51250a.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..45288be482679de77f599fe2b94ef5b32dc9a382
--- /dev/null
+++ b/go/test/typeparam/issue51250a.dir/main.go
@@ -0,0 +1,24 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./a"
+ "./b"
+)
+
+func main() {
+ switch b.I.(type) {
+ case a.G[b.T]:
+ case int:
+ panic("bad")
+ case float64:
+ panic("bad")
+ default:
+ panic("bad")
+ }
+
+ b.F(a.G[b.T]{})
+}
diff --git a/go/test/typeparam/issue51367.dir/a.go b/go/test/typeparam/issue51367.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..be0c3b0688bb91e68fdb3484c5f861b128e93a8f
--- /dev/null
+++ b/go/test/typeparam/issue51367.dir/a.go
@@ -0,0 +1,14 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type A[T any] struct{}
+
+func (_ A[T]) Method() {}
+
+func DoSomething[P any]() {
+ a := A[*byte]{}
+ a.Method()
+}
diff --git a/go/test/typeparam/issue51367.dir/main.go b/go/test/typeparam/issue51367.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..1de8793d4db0c9c4de77a449a791f6e1675e33da
--- /dev/null
+++ b/go/test/typeparam/issue51367.dir/main.go
@@ -0,0 +1,13 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./a"
+)
+
+func main() {
+ a.DoSomething[byte]()
+}
diff --git a/go/test/typeparam/issue51423.dir/a.go b/go/test/typeparam/issue51423.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..e824d0e1654d604204d9c6500d8a0d56834001e7
--- /dev/null
+++ b/go/test/typeparam/issue51423.dir/a.go
@@ -0,0 +1,17 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type Comparator[T any] func(v1, v2 T) int
+
+func CompareInt[T ~int](a, b T) int {
+ if a < b {
+ return -1
+ }
+ if a == b {
+ return 0
+ }
+ return 1
+}
diff --git a/go/test/typeparam/issue51423.dir/b.go b/go/test/typeparam/issue51423.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..2bad19fbdac9f62797a88fad53ded351023fe6d5
--- /dev/null
+++ b/go/test/typeparam/issue51423.dir/b.go
@@ -0,0 +1,11 @@
+package b
+
+import "./a"
+
+func C() a.Comparator[int] {
+ return a.CompareInt[int]
+}
+
+func main() {
+ _ = C()(1, 2)
+}
diff --git a/go/test/typeparam/issue51836.dir/a.go b/go/test/typeparam/issue51836.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..e9223c9aa8270f1b9b82a23e4fe3340c5882f2e6
--- /dev/null
+++ b/go/test/typeparam/issue51836.dir/a.go
@@ -0,0 +1,8 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type T[K any] struct {
+}
diff --git a/go/test/typeparam/issue51836.dir/aa.go b/go/test/typeparam/issue51836.dir/aa.go
new file mode 100644
index 0000000000000000000000000000000000000000..d774be282e5aa814078fa94af7272cf915cef254
--- /dev/null
+++ b/go/test/typeparam/issue51836.dir/aa.go
@@ -0,0 +1,13 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+import (
+ "./a"
+)
+
+type T[K any] struct {
+ t a.T[K]
+}
diff --git a/go/test/typeparam/issue51836.dir/p.go b/go/test/typeparam/issue51836.dir/p.go
new file mode 100644
index 0000000000000000000000000000000000000000..98197ae0fd9dac5df2e48a52f19a5de210343f2d
--- /dev/null
+++ b/go/test/typeparam/issue51836.dir/p.go
@@ -0,0 +1,11 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package p
+
+import (
+ a "./aa"
+)
+
+var Foo a.T[int]
diff --git a/go/test/typeparam/issue52117.dir/a.go b/go/test/typeparam/issue52117.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..e571ea94623cc707777c16ba0578af487e934254
--- /dev/null
+++ b/go/test/typeparam/issue52117.dir/a.go
@@ -0,0 +1,15 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func Compare[T int | uint](a, b T) int {
+ return 0
+}
+
+type Slice[T int | uint] struct{}
+
+func (l Slice[T]) Comparator() func(v1, v2 T) int {
+ return Compare[T]
+}
diff --git a/go/test/typeparam/issue52117.dir/b.go b/go/test/typeparam/issue52117.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..3d3bf4ced9e2f8315391f6be2993848520ff2be0
--- /dev/null
+++ b/go/test/typeparam/issue52117.dir/b.go
@@ -0,0 +1,7 @@
+package b
+
+import "./a"
+
+func Test() {
+ var _ a.Slice[uint]
+}
diff --git a/go/test/typeparam/issue54302.dir/a.go b/go/test/typeparam/issue54302.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..52875ab5e15808181672567b8e48dd8f2f306c8c
--- /dev/null
+++ b/go/test/typeparam/issue54302.dir/a.go
@@ -0,0 +1,20 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func A() {
+ B[int](new(G[int]))
+}
+
+func B[T any](iface interface{ M(T) }) {
+ x, ok := iface.(*G[T])
+ if !ok || iface != x {
+ panic("FAIL")
+ }
+}
+
+type G[T any] struct{}
+
+func (*G[T]) M(T) {}
diff --git a/go/test/typeparam/issue54302.dir/main.go b/go/test/typeparam/issue54302.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..b4c6cd142dcfc8572371a78c1c916d36d3c8e25b
--- /dev/null
+++ b/go/test/typeparam/issue54302.dir/main.go
@@ -0,0 +1,11 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+func main() {
+ a.A()
+}
diff --git a/go/test/typeparam/listimp.dir/a.go b/go/test/typeparam/listimp.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..e9c46d6f325b8f7ab4358752faeb327a7ae9bbee
--- /dev/null
+++ b/go/test/typeparam/listimp.dir/a.go
@@ -0,0 +1,53 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type Ordered interface {
+ ~int | ~int8 | ~int16 | ~int32 | ~int64 |
+ ~uint | ~uint8 | ~uint16 | ~uint32 | ~uint64 | ~uintptr |
+ ~float32 | ~float64 |
+ ~string
+}
+
+// List is a linked list of ordered values of type T.
+type List[T Ordered] struct {
+ Next *List[T]
+ Val T
+}
+
+func (l *List[T]) Largest() T {
+ var max T
+ for p := l; p != nil; p = p.Next {
+ if p.Val > max {
+ max = p.Val
+ }
+ }
+ return max
+}
+
+type OrderedNum interface {
+ ~int | ~int8 | ~int16 | ~int32 | ~int64 |
+ ~uint | ~uint8 | ~uint16 | ~uint32 | ~uint64 | ~uintptr |
+ ~float32 | ~float64
+}
+
+// ListNum is a linked _List of ordered numeric values of type T.
+type ListNum[T OrderedNum] struct {
+ Next *ListNum[T]
+ Val T
+}
+
+const Clip = 5
+
+// ClippedLargest returns the largest in the list of OrderNums, but a max of 5.
+func (l *ListNum[T]) ClippedLargest() T {
+ var max T
+ for p := l; p != nil; p = p.Next {
+ if p.Val > max && p.Val < Clip {
+ max = p.Val
+ }
+ }
+ return max
+}
diff --git a/go/test/typeparam/listimp.dir/main.go b/go/test/typeparam/listimp.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..652a34a0828846ef93dc4475f30e5e6b62b7a11f
--- /dev/null
+++ b/go/test/typeparam/listimp.dir/main.go
@@ -0,0 +1,52 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./a"
+ "fmt"
+)
+
+func main() {
+ i3 := &a.List[int]{nil, 1}
+ i2 := &a.List[int]{i3, 3}
+ i1 := &a.List[int]{i2, 2}
+ if got, want := i1.Largest(), 3; got != want {
+ panic(fmt.Sprintf("got %d, want %d", got, want))
+ }
+
+ b3 := &a.List[byte]{nil, byte(1)}
+ b2 := &a.List[byte]{b3, byte(3)}
+ b1 := &a.List[byte]{b2, byte(2)}
+ if got, want := b1.Largest(), byte(3); got != want {
+ panic(fmt.Sprintf("got %d, want %d", got, want))
+ }
+
+ f3 := &a.List[float64]{nil, 13.5}
+ f2 := &a.List[float64]{f3, 1.2}
+ f1 := &a.List[float64]{f2, 4.5}
+ if got, want := f1.Largest(), 13.5; got != want {
+ panic(fmt.Sprintf("got %f, want %f", got, want))
+ }
+
+ s3 := &a.List[string]{nil, "dd"}
+ s2 := &a.List[string]{s3, "aa"}
+ s1 := &a.List[string]{s2, "bb"}
+ if got, want := s1.Largest(), "dd"; got != want {
+ panic(fmt.Sprintf("got %s, want %s", got, want))
+ }
+ j3 := &a.ListNum[int]{nil, 1}
+ j2 := &a.ListNum[int]{j3, 32}
+ j1 := &a.ListNum[int]{j2, 2}
+ if got, want := j1.ClippedLargest(), 2; got != want {
+ panic(fmt.Sprintf("got %d, want %d", got, want))
+ }
+ g3 := &a.ListNum[float64]{nil, 13.5}
+ g2 := &a.ListNum[float64]{g3, 1.2}
+ g1 := &a.ListNum[float64]{g2, 4.5}
+ if got, want := g1.ClippedLargest(), 4.5; got != want {
+ panic(fmt.Sprintf("got %f, want %f", got, want))
+ }
+}
diff --git a/go/test/typeparam/listimp2.dir/a.go b/go/test/typeparam/listimp2.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..3a7dfc3999a0db856c877a5cc2c4f21c899e801c
--- /dev/null
+++ b/go/test/typeparam/listimp2.dir/a.go
@@ -0,0 +1,298 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+import (
+ "fmt"
+)
+
+// Element is an element of a linked list.
+type Element[T any] struct {
+ // Next and previous pointers in the doubly-linked list of elements.
+ // To simplify the implementation, internally a list l is implemented
+ // as a ring, such that &l.root is both the next element of the last
+ // list element (l.Back()) and the previous element of the first list
+ // element (l.Front()).
+ next, prev *Element[T]
+
+ // The list to which this element belongs.
+ list *List[T]
+
+ // The value stored with this element.
+ Value T
+}
+
+// Next returns the next list element or nil.
+func (e *Element[T]) Next() *Element[T] {
+ if p := e.next; e.list != nil && p != &e.list.root {
+ return p
+ }
+ return nil
+}
+
+// Prev returns the previous list element or nil.
+func (e *Element[T]) Prev() *Element[T] {
+ if p := e.prev; e.list != nil && p != &e.list.root {
+ return p
+ }
+ return nil
+}
+
+// List represents a doubly linked list.
+// The zero value for List is an empty list ready to use.
+type List[T any] struct {
+ root Element[T] // sentinel list element, only &root, root.prev, and root.next are used
+ len int // current list length excluding (this) sentinel element
+}
+
+// Init initializes or clears list l.
+func (l *List[T]) Init() *List[T] {
+ l.root.next = &l.root
+ l.root.prev = &l.root
+ l.len = 0
+ return l
+}
+
+// New returns an initialized list.
+func New[T any]() *List[T] { return new(List[T]).Init() }
+
+// Len returns the number of elements of list l.
+// The complexity is O(1).
+func (l *List[_]) Len() int { return l.len }
+
+// Front returns the first element of list l or nil if the list is empty.
+func (l *List[T]) Front() *Element[T] {
+ if l.len == 0 {
+ return nil
+ }
+ return l.root.next
+}
+
+// Back returns the last element of list l or nil if the list is empty.
+func (l *List[T]) Back() *Element[T] {
+ if l.len == 0 {
+ return nil
+ }
+ return l.root.prev
+}
+
+// lazyInit lazily initializes a zero List value.
+func (l *List[_]) lazyInit() {
+ if l.root.next == nil {
+ l.Init()
+ }
+}
+
+// insert inserts e after at, increments l.len, and returns e.
+func (l *List[T]) insert(e, at *Element[T]) *Element[T] {
+ e.prev = at
+ e.next = at.next
+ e.prev.next = e
+ e.next.prev = e
+ e.list = l
+ l.len++
+ return e
+}
+
+// insertValue is a convenience wrapper for insert(&Element[T]{Value: v}, at).
+func (l *List[T]) insertValue(v T, at *Element[T]) *Element[T] {
+ return l.insert(&Element[T]{Value: v}, at)
+}
+
+// remove removes e from its list, decrements l.len, and returns e.
+func (l *List[T]) remove(e *Element[T]) *Element[T] {
+ e.prev.next = e.next
+ e.next.prev = e.prev
+ e.next = nil // avoid memory leaks
+ e.prev = nil // avoid memory leaks
+ e.list = nil
+ l.len--
+ return e
+}
+
+// move moves e to next to at and returns e.
+func (l *List[T]) move(e, at *Element[T]) *Element[T] {
+ if e == at {
+ return e
+ }
+ e.prev.next = e.next
+ e.next.prev = e.prev
+
+ e.prev = at
+ e.next = at.next
+ e.prev.next = e
+ e.next.prev = e
+
+ return e
+}
+
+// Remove removes e from l if e is an element of list l.
+// It returns the element value e.Value.
+// The element must not be nil.
+func (l *List[T]) Remove(e *Element[T]) T {
+ if e.list == l {
+ // if e.list == l, l must have been initialized when e was inserted
+ // in l or l == nil (e is a zero Element) and l.remove will crash
+ l.remove(e)
+ }
+ return e.Value
+}
+
+// PushFront inserts a new element e with value v at the front of list l and returns e.
+func (l *List[T]) PushFront(v T) *Element[T] {
+ l.lazyInit()
+ return l.insertValue(v, &l.root)
+}
+
+// PushBack inserts a new element e with value v at the back of list l and returns e.
+func (l *List[T]) PushBack(v T) *Element[T] {
+ l.lazyInit()
+ return l.insertValue(v, l.root.prev)
+}
+
+// InsertBefore inserts a new element e with value v immediately before mark and returns e.
+// If mark is not an element of l, the list is not modified.
+// The mark must not be nil.
+func (l *List[T]) InsertBefore(v T, mark *Element[T]) *Element[T] {
+ if mark.list != l {
+ return nil
+ }
+ // see comment in List.Remove about initialization of l
+ return l.insertValue(v, mark.prev)
+}
+
+// InsertAfter inserts a new element e with value v immediately after mark and returns e.
+// If mark is not an element of l, the list is not modified.
+// The mark must not be nil.
+func (l *List[T]) InsertAfter(v T, mark *Element[T]) *Element[T] {
+ if mark.list != l {
+ return nil
+ }
+ // see comment in List.Remove about initialization of l
+ return l.insertValue(v, mark)
+}
+
+// MoveToFront moves element e to the front of list l.
+// If e is not an element of l, the list is not modified.
+// The element must not be nil.
+func (l *List[T]) MoveToFront(e *Element[T]) {
+ if e.list != l || l.root.next == e {
+ return
+ }
+ // see comment in List.Remove about initialization of l
+ l.move(e, &l.root)
+}
+
+// MoveToBack moves element e to the back of list l.
+// If e is not an element of l, the list is not modified.
+// The element must not be nil.
+func (l *List[T]) MoveToBack(e *Element[T]) {
+ if e.list != l || l.root.prev == e {
+ return
+ }
+ // see comment in List.Remove about initialization of l
+ l.move(e, l.root.prev)
+}
+
+// MoveBefore moves element e to its new position before mark.
+// If e or mark is not an element of l, or e == mark, the list is not modified.
+// The element and mark must not be nil.
+func (l *List[T]) MoveBefore(e, mark *Element[T]) {
+ if e.list != l || e == mark || mark.list != l {
+ return
+ }
+ l.move(e, mark.prev)
+}
+
+// MoveAfter moves element e to its new position after mark.
+// If e or mark is not an element of l, or e == mark, the list is not modified.
+// The element and mark must not be nil.
+func (l *List[T]) MoveAfter(e, mark *Element[T]) {
+ if e.list != l || e == mark || mark.list != l {
+ return
+ }
+ l.move(e, mark)
+}
+
+// PushBackList inserts a copy of an other list at the back of list l.
+// The lists l and other may be the same. They must not be nil.
+func (l *List[T]) PushBackList(other *List[T]) {
+ l.lazyInit()
+ for i, e := other.Len(), other.Front(); i > 0; i, e = i-1, e.Next() {
+ l.insertValue(e.Value, l.root.prev)
+ }
+}
+
+// PushFrontList inserts a copy of an other list at the front of list l.
+// The lists l and other may be the same. They must not be nil.
+func (l *List[T]) PushFrontList(other *List[T]) {
+ l.lazyInit()
+ for i, e := other.Len(), other.Back(); i > 0; i, e = i-1, e.Prev() {
+ l.insertValue(e.Value, &l.root)
+ }
+}
+
+// Transform runs a transform function on a list returning a new list.
+func Transform[TElem1, TElem2 any](lst *List[TElem1], f func(TElem1) TElem2) *List[TElem2] {
+ ret := New[TElem2]()
+ for p := lst.Front(); p != nil; p = p.Next() {
+ ret.PushBack(f(p.Value))
+ }
+ return ret
+}
+
+func CheckListLen[T any](l *List[T], len int) bool {
+ if n := l.Len(); n != len {
+ panic(fmt.Sprintf("l.Len() = %d, want %d", n, len))
+ return false
+ }
+ return true
+}
+
+func CheckListPointers[T any](l *List[T], es []*Element[T]) {
+ root := &l.root
+
+ if !CheckListLen(l, len(es)) {
+ return
+ }
+
+ // zero length lists must be the zero value or properly initialized (sentinel circle)
+ if len(es) == 0 {
+ if l.root.next != nil && l.root.next != root || l.root.prev != nil && l.root.prev != root {
+ panic(fmt.Sprintf("l.root.next = %p, l.root.prev = %p; both should both be nil or %p", l.root.next, l.root.prev, root))
+ }
+ return
+ }
+ // len(es) > 0
+
+ // check internal and external prev/next connections
+ for i, e := range es {
+ prev := root
+ Prev := (*Element[T])(nil)
+ if i > 0 {
+ prev = es[i-1]
+ Prev = prev
+ }
+ if p := e.prev; p != prev {
+ panic(fmt.Sprintf("elt[%d](%p).prev = %p, want %p", i, e, p, prev))
+ }
+ if p := e.Prev(); p != Prev {
+ panic(fmt.Sprintf("elt[%d](%p).Prev() = %p, want %p", i, e, p, Prev))
+ }
+
+ next := root
+ Next := (*Element[T])(nil)
+ if i < len(es)-1 {
+ next = es[i+1]
+ Next = next
+ }
+ if n := e.next; n != next {
+ panic(fmt.Sprintf("elt[%d](%p).next = %p, want %p", i, e, n, next))
+ }
+ if n := e.Next(); n != Next {
+ panic(fmt.Sprintf("elt[%d](%p).Next() = %p, want %p", i, e, n, Next))
+ }
+ }
+}
diff --git a/go/test/typeparam/listimp2.dir/main.go b/go/test/typeparam/listimp2.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..c3b936eada0033ffaecd6c832658f069d8d21357
--- /dev/null
+++ b/go/test/typeparam/listimp2.dir/main.go
@@ -0,0 +1,315 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./a"
+ "fmt"
+ "strconv"
+)
+
+func TestList() {
+ l := a.New[string]()
+ a.CheckListPointers(l, []*(a.Element[string]){})
+
+ // Single element list
+ e := l.PushFront("a")
+ a.CheckListPointers(l, []*(a.Element[string]){e})
+ l.MoveToFront(e)
+ a.CheckListPointers(l, []*(a.Element[string]){e})
+ l.MoveToBack(e)
+ a.CheckListPointers(l, []*(a.Element[string]){e})
+ l.Remove(e)
+ a.CheckListPointers(l, []*(a.Element[string]){})
+
+ // Bigger list
+ l2 := a.New[int]()
+ e2 := l2.PushFront(2)
+ e1 := l2.PushFront(1)
+ e3 := l2.PushBack(3)
+ e4 := l2.PushBack(600)
+ a.CheckListPointers(l2, []*(a.Element[int]){e1, e2, e3, e4})
+
+ l2.Remove(e2)
+ a.CheckListPointers(l2, []*(a.Element[int]){e1, e3, e4})
+
+ l2.MoveToFront(e3) // move from middle
+ a.CheckListPointers(l2, []*(a.Element[int]){e3, e1, e4})
+
+ l2.MoveToFront(e1)
+ l2.MoveToBack(e3) // move from middle
+ a.CheckListPointers(l2, []*(a.Element[int]){e1, e4, e3})
+
+ l2.MoveToFront(e3) // move from back
+ a.CheckListPointers(l2, []*(a.Element[int]){e3, e1, e4})
+ l2.MoveToFront(e3) // should be no-op
+ a.CheckListPointers(l2, []*(a.Element[int]){e3, e1, e4})
+
+ l2.MoveToBack(e3) // move from front
+ a.CheckListPointers(l2, []*(a.Element[int]){e1, e4, e3})
+ l2.MoveToBack(e3) // should be no-op
+ a.CheckListPointers(l2, []*(a.Element[int]){e1, e4, e3})
+
+ e2 = l2.InsertBefore(2, e1) // insert before front
+ a.CheckListPointers(l2, []*(a.Element[int]){e2, e1, e4, e3})
+ l2.Remove(e2)
+ e2 = l2.InsertBefore(2, e4) // insert before middle
+ a.CheckListPointers(l2, []*(a.Element[int]){e1, e2, e4, e3})
+ l2.Remove(e2)
+ e2 = l2.InsertBefore(2, e3) // insert before back
+ a.CheckListPointers(l2, []*(a.Element[int]){e1, e4, e2, e3})
+ l2.Remove(e2)
+
+ e2 = l2.InsertAfter(2, e1) // insert after front
+ a.CheckListPointers(l2, []*(a.Element[int]){e1, e2, e4, e3})
+ l2.Remove(e2)
+ e2 = l2.InsertAfter(2, e4) // insert after middle
+ a.CheckListPointers(l2, []*(a.Element[int]){e1, e4, e2, e3})
+ l2.Remove(e2)
+ e2 = l2.InsertAfter(2, e3) // insert after back
+ a.CheckListPointers(l2, []*(a.Element[int]){e1, e4, e3, e2})
+ l2.Remove(e2)
+
+ // Check standard iteration.
+ sum := 0
+ for e := l2.Front(); e != nil; e = e.Next() {
+ sum += e.Value
+ }
+ if sum != 604 {
+ panic(fmt.Sprintf("sum over l = %d, want 604", sum))
+ }
+
+ // Clear all elements by iterating
+ var next *a.Element[int]
+ for e := l2.Front(); e != nil; e = next {
+ next = e.Next()
+ l2.Remove(e)
+ }
+ a.CheckListPointers(l2, []*(a.Element[int]){})
+}
+
+func checkList[T comparable](l *a.List[T], es []interface{}) {
+ if !a.CheckListLen(l, len(es)) {
+ return
+ }
+
+ i := 0
+ for e := l.Front(); e != nil; e = e.Next() {
+ le := e.Value
+ // Comparison between a generically-typed variable le and an interface.
+ if le != es[i] {
+ panic(fmt.Sprintf("elt[%d].Value = %v, want %v", i, le, es[i]))
+ }
+ i++
+ }
+}
+
+func TestExtending() {
+ l1 := a.New[int]()
+ l2 := a.New[int]()
+
+ l1.PushBack(1)
+ l1.PushBack(2)
+ l1.PushBack(3)
+
+ l2.PushBack(4)
+ l2.PushBack(5)
+
+ l3 := a.New[int]()
+ l3.PushBackList(l1)
+ checkList(l3, []interface{}{1, 2, 3})
+ l3.PushBackList(l2)
+ checkList(l3, []interface{}{1, 2, 3, 4, 5})
+
+ l3 = a.New[int]()
+ l3.PushFrontList(l2)
+ checkList(l3, []interface{}{4, 5})
+ l3.PushFrontList(l1)
+ checkList(l3, []interface{}{1, 2, 3, 4, 5})
+
+ checkList(l1, []interface{}{1, 2, 3})
+ checkList(l2, []interface{}{4, 5})
+
+ l3 = a.New[int]()
+ l3.PushBackList(l1)
+ checkList(l3, []interface{}{1, 2, 3})
+ l3.PushBackList(l3)
+ checkList(l3, []interface{}{1, 2, 3, 1, 2, 3})
+
+ l3 = a.New[int]()
+ l3.PushFrontList(l1)
+ checkList(l3, []interface{}{1, 2, 3})
+ l3.PushFrontList(l3)
+ checkList(l3, []interface{}{1, 2, 3, 1, 2, 3})
+
+ l3 = a.New[int]()
+ l1.PushBackList(l3)
+ checkList(l1, []interface{}{1, 2, 3})
+ l1.PushFrontList(l3)
+ checkList(l1, []interface{}{1, 2, 3})
+}
+
+func TestRemove() {
+ l := a.New[int]()
+ e1 := l.PushBack(1)
+ e2 := l.PushBack(2)
+ a.CheckListPointers(l, []*(a.Element[int]){e1, e2})
+ e := l.Front()
+ l.Remove(e)
+ a.CheckListPointers(l, []*(a.Element[int]){e2})
+ l.Remove(e)
+ a.CheckListPointers(l, []*(a.Element[int]){e2})
+}
+
+func TestIssue4103() {
+ l1 := a.New[int]()
+ l1.PushBack(1)
+ l1.PushBack(2)
+
+ l2 := a.New[int]()
+ l2.PushBack(3)
+ l2.PushBack(4)
+
+ e := l1.Front()
+ l2.Remove(e) // l2 should not change because e is not an element of l2
+ if n := l2.Len(); n != 2 {
+ panic(fmt.Sprintf("l2.Len() = %d, want 2", n))
+ }
+
+ l1.InsertBefore(8, e)
+ if n := l1.Len(); n != 3 {
+ panic(fmt.Sprintf("l1.Len() = %d, want 3", n))
+ }
+}
+
+func TestIssue6349() {
+ l := a.New[int]()
+ l.PushBack(1)
+ l.PushBack(2)
+
+ e := l.Front()
+ l.Remove(e)
+ if e.Value != 1 {
+ panic(fmt.Sprintf("e.value = %d, want 1", e.Value))
+ }
+ if e.Next() != nil {
+ panic(fmt.Sprintf("e.Next() != nil"))
+ }
+ if e.Prev() != nil {
+ panic(fmt.Sprintf("e.Prev() != nil"))
+ }
+}
+
+func TestMove() {
+ l := a.New[int]()
+ e1 := l.PushBack(1)
+ e2 := l.PushBack(2)
+ e3 := l.PushBack(3)
+ e4 := l.PushBack(4)
+
+ l.MoveAfter(e3, e3)
+ a.CheckListPointers(l, []*(a.Element[int]){e1, e2, e3, e4})
+ l.MoveBefore(e2, e2)
+ a.CheckListPointers(l, []*(a.Element[int]){e1, e2, e3, e4})
+
+ l.MoveAfter(e3, e2)
+ a.CheckListPointers(l, []*(a.Element[int]){e1, e2, e3, e4})
+ l.MoveBefore(e2, e3)
+ a.CheckListPointers(l, []*(a.Element[int]){e1, e2, e3, e4})
+
+ l.MoveBefore(e2, e4)
+ a.CheckListPointers(l, []*(a.Element[int]){e1, e3, e2, e4})
+ e2, e3 = e3, e2
+
+ l.MoveBefore(e4, e1)
+ a.CheckListPointers(l, []*(a.Element[int]){e4, e1, e2, e3})
+ e1, e2, e3, e4 = e4, e1, e2, e3
+
+ l.MoveAfter(e4, e1)
+ a.CheckListPointers(l, []*(a.Element[int]){e1, e4, e2, e3})
+ e2, e3, e4 = e4, e2, e3
+
+ l.MoveAfter(e2, e3)
+ a.CheckListPointers(l, []*(a.Element[int]){e1, e3, e2, e4})
+ e2, e3 = e3, e2
+}
+
+// Test PushFront, PushBack, PushFrontList, PushBackList with uninitialized a.List
+func TestZeroList() {
+ var l1 = new(a.List[int])
+ l1.PushFront(1)
+ checkList(l1, []interface{}{1})
+
+ var l2 = new(a.List[int])
+ l2.PushBack(1)
+ checkList(l2, []interface{}{1})
+
+ var l3 = new(a.List[int])
+ l3.PushFrontList(l1)
+ checkList(l3, []interface{}{1})
+
+ var l4 = new(a.List[int])
+ l4.PushBackList(l2)
+ checkList(l4, []interface{}{1})
+}
+
+// Test that a list l is not modified when calling InsertBefore with a mark that is not an element of l.
+func TestInsertBeforeUnknownMark() {
+ var l a.List[int]
+ l.PushBack(1)
+ l.PushBack(2)
+ l.PushBack(3)
+ l.InsertBefore(1, new(a.Element[int]))
+ checkList(&l, []interface{}{1, 2, 3})
+}
+
+// Test that a list l is not modified when calling InsertAfter with a mark that is not an element of l.
+func TestInsertAfterUnknownMark() {
+ var l a.List[int]
+ l.PushBack(1)
+ l.PushBack(2)
+ l.PushBack(3)
+ l.InsertAfter(1, new(a.Element[int]))
+ checkList(&l, []interface{}{1, 2, 3})
+}
+
+// Test that a list l is not modified when calling MoveAfter or MoveBefore with a mark that is not an element of l.
+func TestMoveUnknownMark() {
+ var l1 a.List[int]
+ e1 := l1.PushBack(1)
+
+ var l2 a.List[int]
+ e2 := l2.PushBack(2)
+
+ l1.MoveAfter(e1, e2)
+ checkList(&l1, []interface{}{1})
+ checkList(&l2, []interface{}{2})
+
+ l1.MoveBefore(e1, e2)
+ checkList(&l1, []interface{}{1})
+ checkList(&l2, []interface{}{2})
+}
+
+// Test the Transform function.
+func TestTransform() {
+ l1 := a.New[int]()
+ l1.PushBack(1)
+ l1.PushBack(2)
+ l2 := a.Transform(l1, strconv.Itoa)
+ checkList(l2, []interface{}{"1", "2"})
+}
+
+func main() {
+ TestList()
+ TestExtending()
+ TestRemove()
+ TestIssue4103()
+ TestIssue6349()
+ TestMove()
+ TestZeroList()
+ TestInsertBeforeUnknownMark()
+ TestInsertAfterUnknownMark()
+ TestTransform()
+}
diff --git a/go/test/typeparam/mapimp.dir/a.go b/go/test/typeparam/mapimp.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..cbfa80ac6b1d338bf40a4d6c76da0f3f419c60b2
--- /dev/null
+++ b/go/test/typeparam/mapimp.dir/a.go
@@ -0,0 +1,15 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+// Map calls the function f on every element of the slice s,
+// returning a new slice of the results.
+func Mapper[F, T any](s []F, f func(F) T) []T {
+ r := make([]T, len(s))
+ for i, v := range s {
+ r[i] = f(v)
+ }
+ return r
+}
diff --git a/go/test/typeparam/mapimp.dir/main.go b/go/test/typeparam/mapimp.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..8a56ce2bfb391f7e48938eb574fd1ce0a3644b76
--- /dev/null
+++ b/go/test/typeparam/mapimp.dir/main.go
@@ -0,0 +1,28 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./a"
+ "fmt"
+ "reflect"
+ "strconv"
+)
+
+func main() {
+ got := a.Mapper([]int{1, 2, 3}, strconv.Itoa)
+ want := []string{"1", "2", "3"}
+ if !reflect.DeepEqual(got, want) {
+ panic(fmt.Sprintf("got %s, want %s", got, want))
+ }
+
+ fgot := a.Mapper([]float64{2.5, 2.3, 3.5}, func(f float64) string {
+ return strconv.FormatFloat(f, 'f', -1, 64)
+ })
+ fwant := []string{"2.5", "2.3", "3.5"}
+ if !reflect.DeepEqual(fgot, fwant) {
+ panic(fmt.Sprintf("got %s, want %s", fgot, fwant))
+ }
+}
diff --git a/go/test/typeparam/mapsimp.dir/a.go b/go/test/typeparam/mapsimp.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..696e2a568014a9b0edb23cb9438557d2e2914526
--- /dev/null
+++ b/go/test/typeparam/mapsimp.dir/a.go
@@ -0,0 +1,108 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+// SliceEqual reports whether two slices are equal: the same length and all
+// elements equal. All floating point NaNs are considered equal.
+func SliceEqual[Elem comparable](s1, s2 []Elem) bool {
+ if len(s1) != len(s2) {
+ return false
+ }
+ for i, v1 := range s1 {
+ v2 := s2[i]
+ if v1 != v2 {
+ isNaN := func(f Elem) bool { return f != f }
+ if !isNaN(v1) || !isNaN(v2) {
+ return false
+ }
+ }
+ }
+ return true
+}
+
+// Keys returns the keys of the map m.
+// The keys will be an indeterminate order.
+func Keys[K comparable, V any](m map[K]V) []K {
+ r := make([]K, 0, len(m))
+ for k := range m {
+ r = append(r, k)
+ }
+ return r
+}
+
+// Values returns the values of the map m.
+// The values will be in an indeterminate order.
+func Values[K comparable, V any](m map[K]V) []V {
+ r := make([]V, 0, len(m))
+ for _, v := range m {
+ r = append(r, v)
+ }
+ return r
+}
+
+// Equal reports whether two maps contain the same key/value pairs.
+// Values are compared using ==.
+func Equal[K, V comparable](m1, m2 map[K]V) bool {
+ if len(m1) != len(m2) {
+ return false
+ }
+ for k, v1 := range m1 {
+ if v2, ok := m2[k]; !ok || v1 != v2 {
+ return false
+ }
+ }
+ return true
+}
+
+// Copy returns a copy of m.
+func Copy[K comparable, V any](m map[K]V) map[K]V {
+ r := make(map[K]V, len(m))
+ for k, v := range m {
+ r[k] = v
+ }
+ return r
+}
+
+// Add adds all key/value pairs in m2 to m1. Keys in m2 that are already
+// present in m1 will be overwritten with the value in m2.
+func Add[K comparable, V any](m1, m2 map[K]V) {
+ for k, v := range m2 {
+ m1[k] = v
+ }
+}
+
+// Sub removes all keys in m2 from m1. Keys in m2 that are not present
+// in m1 are ignored. The values in m2 are ignored.
+func Sub[K comparable, V any](m1, m2 map[K]V) {
+ for k := range m2 {
+ delete(m1, k)
+ }
+}
+
+// Intersect removes all keys from m1 that are not present in m2.
+// Keys in m2 that are not in m1 are ignored. The values in m2 are ignored.
+func Intersect[K comparable, V any](m1, m2 map[K]V) {
+ for k := range m1 {
+ if _, ok := m2[k]; !ok {
+ delete(m1, k)
+ }
+ }
+}
+
+// Filter deletes any key/value pairs from m for which f returns false.
+func Filter[K comparable, V any](m map[K]V, f func(K, V) bool) {
+ for k, v := range m {
+ if !f(k, v) {
+ delete(m, k)
+ }
+ }
+}
+
+// TransformValues applies f to each value in m. The keys remain unchanged.
+func TransformValues[K comparable, V any](m map[K]V, f func(V) V) {
+ for k, v := range m {
+ m[k] = f(v)
+ }
+}
diff --git a/go/test/typeparam/mapsimp.dir/main.go b/go/test/typeparam/mapsimp.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..45f7d39f931e009444e51f1e14728930b407d9cf
--- /dev/null
+++ b/go/test/typeparam/mapsimp.dir/main.go
@@ -0,0 +1,156 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./a"
+ "fmt"
+ "math"
+ "sort"
+)
+
+var m1 = map[int]int{1: 2, 2: 4, 4: 8, 8: 16}
+var m2 = map[int]string{1: "2", 2: "4", 4: "8", 8: "16"}
+
+func TestKeys() {
+ want := []int{1, 2, 4, 8}
+
+ got1 := a.Keys(m1)
+ sort.Ints(got1)
+ if !a.SliceEqual(got1, want) {
+ panic(fmt.Sprintf("a.Keys(%v) = %v, want %v", m1, got1, want))
+ }
+
+ got2 := a.Keys(m2)
+ sort.Ints(got2)
+ if !a.SliceEqual(got2, want) {
+ panic(fmt.Sprintf("a.Keys(%v) = %v, want %v", m2, got2, want))
+ }
+}
+
+func TestValues() {
+ got1 := a.Values(m1)
+ want1 := []int{2, 4, 8, 16}
+ sort.Ints(got1)
+ if !a.SliceEqual(got1, want1) {
+ panic(fmt.Sprintf("a.Values(%v) = %v, want %v", m1, got1, want1))
+ }
+
+ got2 := a.Values(m2)
+ want2 := []string{"16", "2", "4", "8"}
+ sort.Strings(got2)
+ if !a.SliceEqual(got2, want2) {
+ panic(fmt.Sprintf("a.Values(%v) = %v, want %v", m2, got2, want2))
+ }
+}
+
+func TestEqual() {
+ if !a.Equal(m1, m1) {
+ panic(fmt.Sprintf("a.Equal(%v, %v) = false, want true", m1, m1))
+ }
+ if a.Equal(m1, nil) {
+ panic(fmt.Sprintf("a.Equal(%v, nil) = true, want false", m1))
+ }
+ if a.Equal(nil, m1) {
+ panic(fmt.Sprintf("a.Equal(nil, %v) = true, want false", m1))
+ }
+ if !a.Equal[int, int](nil, nil) {
+ panic("a.Equal(nil, nil) = false, want true")
+ }
+ if ms := map[int]int{1: 2}; a.Equal(m1, ms) {
+ panic(fmt.Sprintf("a.Equal(%v, %v) = true, want false", m1, ms))
+ }
+
+ // Comparing NaN for equality is expected to fail.
+ mf := map[int]float64{1: 0, 2: math.NaN()}
+ if a.Equal(mf, mf) {
+ panic(fmt.Sprintf("a.Equal(%v, %v) = true, want false", mf, mf))
+ }
+}
+
+func TestCopy() {
+ m2 := a.Copy(m1)
+ if !a.Equal(m1, m2) {
+ panic(fmt.Sprintf("a.Copy(%v) = %v, want %v", m1, m2, m1))
+ }
+ m2[16] = 32
+ if a.Equal(m1, m2) {
+ panic(fmt.Sprintf("a.Equal(%v, %v) = true, want false", m1, m2))
+ }
+}
+
+func TestAdd() {
+ mc := a.Copy(m1)
+ a.Add(mc, mc)
+ if !a.Equal(mc, m1) {
+ panic(fmt.Sprintf("a.Add(%v, %v) = %v, want %v", m1, m1, mc, m1))
+ }
+ a.Add(mc, map[int]int{16: 32})
+ want := map[int]int{1: 2, 2: 4, 4: 8, 8: 16, 16: 32}
+ if !a.Equal(mc, want) {
+ panic(fmt.Sprintf("a.Add result = %v, want %v", mc, want))
+ }
+}
+
+func TestSub() {
+ mc := a.Copy(m1)
+ a.Sub(mc, mc)
+ if len(mc) > 0 {
+ panic(fmt.Sprintf("a.Sub(%v, %v) = %v, want empty map", m1, m1, mc))
+ }
+ mc = a.Copy(m1)
+ a.Sub(mc, map[int]int{1: 0})
+ want := map[int]int{2: 4, 4: 8, 8: 16}
+ if !a.Equal(mc, want) {
+ panic(fmt.Sprintf("a.Sub result = %v, want %v", mc, want))
+ }
+}
+
+func TestIntersect() {
+ mc := a.Copy(m1)
+ a.Intersect(mc, mc)
+ if !a.Equal(mc, m1) {
+ panic(fmt.Sprintf("a.Intersect(%v, %v) = %v, want %v", m1, m1, mc, m1))
+ }
+ a.Intersect(mc, map[int]int{1: 0, 2: 0})
+ want := map[int]int{1: 2, 2: 4}
+ if !a.Equal(mc, want) {
+ panic(fmt.Sprintf("a.Intersect result = %v, want %v", mc, want))
+ }
+}
+
+func TestFilter() {
+ mc := a.Copy(m1)
+ a.Filter(mc, func(int, int) bool { return true })
+ if !a.Equal(mc, m1) {
+ panic(fmt.Sprintf("a.Filter(%v, true) = %v, want %v", m1, mc, m1))
+ }
+ a.Filter(mc, func(k, v int) bool { return k < 3 })
+ want := map[int]int{1: 2, 2: 4}
+ if !a.Equal(mc, want) {
+ panic(fmt.Sprintf("a.Filter result = %v, want %v", mc, want))
+ }
+}
+
+func TestTransformValues() {
+ mc := a.Copy(m1)
+ a.TransformValues(mc, func(i int) int { return i / 2 })
+ want := map[int]int{1: 1, 2: 2, 4: 4, 8: 8}
+ if !a.Equal(mc, want) {
+ panic(fmt.Sprintf("a.TransformValues result = %v, want %v", mc, want))
+ }
+}
+
+func main() {
+ TestKeys()
+ TestValues()
+ TestEqual()
+ TestCopy()
+ TestAdd()
+ TestSub()
+ TestIntersect()
+ TestFilter()
+ TestTransformValues()
+}
diff --git a/go/test/typeparam/mdempsky/1.dir/a.go b/go/test/typeparam/mdempsky/1.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..a668eb52dc9dc13d0457e3a8ed3a8049cefac904
--- /dev/null
+++ b/go/test/typeparam/mdempsky/1.dir/a.go
@@ -0,0 +1,9 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type T[_ any] int
+
+func F() { _ = new(T[int]) }
diff --git a/go/test/typeparam/mdempsky/1.dir/b.go b/go/test/typeparam/mdempsky/1.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..af6fef3f6d8bad40de56f7c1803ef5990191abc7
--- /dev/null
+++ b/go/test/typeparam/mdempsky/1.dir/b.go
@@ -0,0 +1,9 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+func main() { a.F() }
diff --git a/go/test/typeparam/mdempsky/1.go b/go/test/typeparam/mdempsky/1.go
new file mode 100644
index 0000000000000000000000000000000000000000..b83fbd7af16a576c16e0fc73b84f1ca0f618b756
--- /dev/null
+++ b/go/test/typeparam/mdempsky/1.go
@@ -0,0 +1,7 @@
+// compiledir
+
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ignored
diff --git a/go/test/typeparam/mdempsky/10.dir/a.go b/go/test/typeparam/mdempsky/10.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..95e111d3470a1a7259d398b3d68ec26f70b6ed65
--- /dev/null
+++ b/go/test/typeparam/mdempsky/10.dir/a.go
@@ -0,0 +1,7 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type I[T any] interface{ M() T }
diff --git a/go/test/typeparam/mdempsky/10.dir/b.go b/go/test/typeparam/mdempsky/10.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..0ef28fd02de3282e61ce2ebb2b0278db1ee4d9f3
--- /dev/null
+++ b/go/test/typeparam/mdempsky/10.dir/b.go
@@ -0,0 +1,17 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+var m = a.I[int].M
+
+var never bool
+
+func main() {
+ if never {
+ m(nil)
+ }
+}
diff --git a/go/test/typeparam/mdempsky/10.go b/go/test/typeparam/mdempsky/10.go
new file mode 100644
index 0000000000000000000000000000000000000000..40df49f83bef07a3f4c5d8fd4000d97484c3f224
--- /dev/null
+++ b/go/test/typeparam/mdempsky/10.go
@@ -0,0 +1,7 @@
+// rundir
+
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ignored
diff --git a/go/test/typeparam/mdempsky/12.dir/a.go b/go/test/typeparam/mdempsky/12.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..ee8be939a8fadd5985e56a491ae2d3e19928ef11
--- /dev/null
+++ b/go/test/typeparam/mdempsky/12.dir/a.go
@@ -0,0 +1,11 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type S[T any] struct {
+ F T
+}
+
+var X = S[int]{}
diff --git a/go/test/typeparam/mdempsky/12.dir/main.go b/go/test/typeparam/mdempsky/12.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..2891322e298867275828c331830fa8bbd3fda114
--- /dev/null
+++ b/go/test/typeparam/mdempsky/12.dir/main.go
@@ -0,0 +1,13 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./a"
+)
+
+func main() {
+ _ = a.X
+}
diff --git a/go/test/typeparam/mdempsky/12.go b/go/test/typeparam/mdempsky/12.go
new file mode 100644
index 0000000000000000000000000000000000000000..0316402a78d0de8f3090a30064ebf2f543c68171
--- /dev/null
+++ b/go/test/typeparam/mdempsky/12.go
@@ -0,0 +1,9 @@
+// rundir
+
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Reported by Cuong Manh Le.
+
+package ignored
diff --git a/go/test/typeparam/mdempsky/13.go b/go/test/typeparam/mdempsky/13.go
new file mode 100644
index 0000000000000000000000000000000000000000..8e11352b5148407f2f857bc2a836fca7d5192f3c
--- /dev/null
+++ b/go/test/typeparam/mdempsky/13.go
@@ -0,0 +1,84 @@
+// run
+
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+// Interface which will be used as a regular interface type and as a type bound.
+type Mer interface{
+ M()
+}
+
+// Interface that is a superset of Mer.
+type Mer2 interface {
+ M()
+ String() string
+}
+
+func F[T Mer](t T) {
+ T.M(t)
+ t.M()
+}
+
+type MyMer int
+
+func (MyMer) M() {}
+func (MyMer) String() string {
+ return "aa"
+}
+
+// Parameterized interface
+type Abs[T any] interface {
+ Abs() T
+}
+
+func G[T Abs[U], U any](t T) {
+ T.Abs(t)
+ t.Abs()
+}
+
+type MyInt int
+func (m MyInt) Abs() MyInt {
+ if m < 0 {
+ return -m
+ }
+ return m
+}
+
+type Abs2 interface {
+ Abs() MyInt
+}
+
+
+func main() {
+ mm := MyMer(3)
+ ms := struct{ Mer }{Mer: mm }
+
+ // Testing F with an interface type arg: Mer and Mer2
+ F[Mer](mm)
+ F[Mer2](mm)
+ F[struct{ Mer }](ms)
+ F[*struct{ Mer }](&ms)
+
+ ms2 := struct { MyMer }{MyMer: mm}
+ ms3 := struct { *MyMer }{MyMer: &mm}
+
+ // Testing F with a concrete type arg
+ F[MyMer](mm)
+ F[*MyMer](&mm)
+ F[struct{ MyMer }](ms2)
+ F[struct{ *MyMer }](ms3)
+ F[*struct{ MyMer }](&ms2)
+ F[*struct{ *MyMer }](&ms3)
+
+ // Testing G with a concrete type args
+ mi := MyInt(-3)
+ G[MyInt,MyInt](mi)
+
+ // Interface Abs[MyInt] holding an mi.
+ intMi := Abs[MyInt](mi)
+ // First type arg here is Abs[MyInt], an interface type.
+ G[Abs[MyInt],MyInt](intMi)
+}
diff --git a/go/test/typeparam/mdempsky/14.go b/go/test/typeparam/mdempsky/14.go
new file mode 100644
index 0000000000000000000000000000000000000000..4af990c49a4a1f5bd3fc055bda84ce258dc7cdb6
--- /dev/null
+++ b/go/test/typeparam/mdempsky/14.go
@@ -0,0 +1,40 @@
+// run
+
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+// Zero returns the zero value of T
+func Zero[T any]() (_ T) {
+ return
+}
+
+type AnyInt[X any] int
+
+func (AnyInt[X]) M() {
+ var have interface{} = Zero[X]()
+ var want interface{} = Zero[MyInt]()
+
+ if have != want {
+ println("FAIL")
+ }
+}
+
+type I interface{ M() }
+
+type MyInt int
+type U = AnyInt[MyInt]
+
+var x = U(0)
+var i I = x
+
+func main() {
+ x.M()
+ U.M(x)
+ (*U).M(&x)
+
+ i.M()
+ I.M(x)
+}
diff --git a/go/test/typeparam/mdempsky/15.go b/go/test/typeparam/mdempsky/15.go
new file mode 100644
index 0000000000000000000000000000000000000000..b03ad6f21048404f917fa8960b004757360314ee
--- /dev/null
+++ b/go/test/typeparam/mdempsky/15.go
@@ -0,0 +1,69 @@
+// run -goexperiment fieldtrack
+
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test that generics, promoted methods, and //go:nointerface
+// interoperate as expected.
+
+package main
+
+import (
+ "reflect"
+)
+
+func TypeString[T any]() string {
+ return reflect.TypeOf(new(T)).Elem().String()
+}
+
+func Test[T, Bad, Good any]() {
+ switch interface{}(new(T)).(type) {
+ case Bad:
+ println("FAIL:", TypeString[T](), "matched", TypeString[Bad]())
+ case Good:
+ // ok
+ default:
+ println("FAIL:", TypeString[T](), "did not match", TypeString[Good]())
+ }
+}
+
+func TestE[T any]() { Test[T, interface{ EBad() }, interface{ EGood() }]() }
+func TestX[T any]() { Test[T, interface{ XBad() }, interface{ XGood() }]() }
+
+type E struct{}
+
+//go:nointerface
+func (E) EBad() {}
+func (E) EGood() {}
+
+type X[T any] struct{ E }
+
+//go:nointerface
+func (X[T]) XBad() {}
+func (X[T]) XGood() {}
+
+type W struct{ X[int] }
+
+func main() {
+ _ = E.EGood
+ _ = E.EBad
+
+ TestE[E]()
+
+ _ = X[int].EGood
+ _ = X[int].EBad
+ _ = X[int].XGood
+ _ = X[int].XBad
+
+ TestE[X[int]]()
+ TestX[X[int]]()
+
+ _ = W.EGood
+ _ = W.EBad
+ _ = W.XGood
+ _ = W.XBad
+
+ TestE[W]()
+ TestX[W]()
+}
diff --git a/go/test/typeparam/mdempsky/16.go b/go/test/typeparam/mdempsky/16.go
new file mode 100644
index 0000000000000000000000000000000000000000..f4f79b9aac5d1583f35dc9e0971d0e3368beef6f
--- /dev/null
+++ b/go/test/typeparam/mdempsky/16.go
@@ -0,0 +1,34 @@
+// run
+
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test that type assertion panics mention the real interface type,
+// not their shape type.
+
+package main
+
+import (
+ "fmt"
+ "runtime"
+ "strings"
+)
+
+func main() {
+ // The exact error message isn't important, but it should mention
+ // `main.T`, not `go.shape.int_0`.
+ if have := F[T](); !strings.Contains(have, "interface { T() main.T }") {
+ fmt.Printf("FAIL: unexpected panic message: %q\n", have)
+ }
+}
+
+type T int
+
+func F[T any]() (res string) {
+ defer func() {
+ res = recover().(runtime.Error).Error()
+ }()
+ _ = interface{ T() T }(nil).(T)
+ return
+}
diff --git a/go/test/typeparam/mdempsky/17.go b/go/test/typeparam/mdempsky/17.go
new file mode 100644
index 0000000000000000000000000000000000000000..12385c3f9eea78c05ee73d576123a3a40aeaa250
--- /dev/null
+++ b/go/test/typeparam/mdempsky/17.go
@@ -0,0 +1,110 @@
+// run
+
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test that implicit conversions of derived types to interface type
+// in range loops work correctly.
+
+package main
+
+import (
+ "fmt"
+ "reflect"
+)
+
+func main() {
+ test{"int", "V"}.match(RangeArrayAny[V]())
+ test{"int", "V"}.match(RangeArrayIface[V]())
+ test{"V"}.match(RangeChanAny[V]())
+ test{"V"}.match(RangeChanIface[V]())
+ test{"K", "V"}.match(RangeMapAny[K, V]())
+ test{"K", "V"}.match(RangeMapIface[K, V]())
+ test{"int", "V"}.match(RangeSliceAny[V]())
+ test{"int", "V"}.match(RangeSliceIface[V]())
+}
+
+type test []string
+
+func (t test) match(args ...any) {
+ if len(t) != len(args) {
+ fmt.Printf("FAIL: want %v values, have %v\n", len(t), len(args))
+ return
+ }
+ for i, want := range t {
+ if have := reflect.TypeOf(args[i]).Name(); want != have {
+ fmt.Printf("FAIL: %v: want type %v, have %v\n", i, want, have)
+ }
+ }
+}
+
+type iface interface{ M() int }
+
+type K int
+type V int
+
+func (K) M() int { return 0 }
+func (V) M() int { return 0 }
+
+func RangeArrayAny[V any]() (k, v any) {
+ for k, v = range [...]V{zero[V]()} {
+ }
+ return
+}
+
+func RangeArrayIface[V iface]() (k any, v iface) {
+ for k, v = range [...]V{zero[V]()} {
+ }
+ return
+}
+
+func RangeChanAny[V any]() (v any) {
+ for v = range chanOf(zero[V]()) {
+ }
+ return
+}
+
+func RangeChanIface[V iface]() (v iface) {
+ for v = range chanOf(zero[V]()) {
+ }
+ return
+}
+
+func RangeMapAny[K comparable, V any]() (k, v any) {
+ for k, v = range map[K]V{zero[K](): zero[V]()} {
+ }
+ return
+}
+
+func RangeMapIface[K interface {
+ iface
+ comparable
+}, V iface]() (k, v iface) {
+ for k, v = range map[K]V{zero[K](): zero[V]()} {
+ }
+ return
+}
+
+func RangeSliceAny[V any]() (k, v any) {
+ for k, v = range []V{zero[V]()} {
+ }
+ return
+}
+
+func RangeSliceIface[V iface]() (k any, v iface) {
+ for k, v = range []V{zero[V]()} {
+ }
+ return
+}
+
+func chanOf[T any](elems ...T) chan T {
+ c := make(chan T, len(elems))
+ for _, elem := range elems {
+ c <- elem
+ }
+ close(c)
+ return c
+}
+
+func zero[T any]() (_ T) { return }
diff --git a/go/test/typeparam/mdempsky/18.go b/go/test/typeparam/mdempsky/18.go
new file mode 100644
index 0000000000000000000000000000000000000000..f4a4ec73c5eb6e35e84510ec165c58bd9e80e466
--- /dev/null
+++ b/go/test/typeparam/mdempsky/18.go
@@ -0,0 +1,26 @@
+// run
+
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test that implicit conversions to interface type in a select/case
+// clause are compiled correctly.
+
+package main
+
+import "fmt"
+
+func main() { f[int]() }
+
+func f[T any]() {
+ ch := make(chan T)
+ close(ch)
+
+ var i, ok any
+ select {
+ case i, ok = <-ch:
+ }
+
+ fmt.Printf("%T %T\n", i, ok)
+}
diff --git a/go/test/typeparam/mdempsky/18.out b/go/test/typeparam/mdempsky/18.out
new file mode 100644
index 0000000000000000000000000000000000000000..19f1c39a22d9959068430358d5f49a01581cd7a5
--- /dev/null
+++ b/go/test/typeparam/mdempsky/18.out
@@ -0,0 +1 @@
+int bool
diff --git a/go/test/typeparam/mdempsky/19.go b/go/test/typeparam/mdempsky/19.go
new file mode 100644
index 0000000000000000000000000000000000000000..53d979a1f249565955b322ce3a01bc80dc61fe20
--- /dev/null
+++ b/go/test/typeparam/mdempsky/19.go
@@ -0,0 +1,32 @@
+// run
+
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test that type parameter methods are handled correctly, even when
+// the instantiating type argument has additional methods.
+
+package main
+
+func main() {
+ F(X(0))
+}
+
+type I interface{ B() }
+
+func F[T I](t T) {
+ CallMethod(t)
+ MethodExpr[T]()(t)
+ MethodVal(t)()
+}
+
+func CallMethod[T I](t T) { t.B() }
+func MethodExpr[T I]() func(T) { return T.B }
+func MethodVal[T I](t T) func() { return t.B }
+
+type X int
+
+func (X) A() { panic("FAIL") }
+func (X) B() {}
+func (X) C() { panic("FAIL") }
diff --git a/go/test/typeparam/mdempsky/2.go b/go/test/typeparam/mdempsky/2.go
new file mode 100644
index 0000000000000000000000000000000000000000..ad548e6a549f92693f5bf91cf991cae0f851f6b8
--- /dev/null
+++ b/go/test/typeparam/mdempsky/2.go
@@ -0,0 +1,20 @@
+// compile
+
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+type T[A, B, C any] int
+
+func (T[A, B, C]) m(x int) {
+ if x <= 0 {
+ return
+ }
+ T[B, C, A](0).m(x - 1)
+}
+
+func main() {
+ T[int8, int16, int32](0).m(3)
+}
diff --git a/go/test/typeparam/mdempsky/20.go b/go/test/typeparam/mdempsky/20.go
new file mode 100644
index 0000000000000000000000000000000000000000..6b97ca102c344052cb5630ef619ca62e122057a9
--- /dev/null
+++ b/go/test/typeparam/mdempsky/20.go
@@ -0,0 +1,38 @@
+// run
+
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test that method expressions with a derived receiver type and
+// promoted methods work correctly.
+
+package main
+
+func main() {
+ F[int]()
+ F[string]()
+}
+
+func F[X any]() {
+ call(T[X].M, T[X].N)
+}
+
+func call[X any](fns ...func(T[X]) int) {
+ for want, fn := range fns {
+ if have := fn(T[X]{}); have != want {
+ println("FAIL:", have, "!=", want)
+ }
+ }
+}
+
+type T[X any] struct {
+ E1
+ *E2[*X]
+}
+
+type E1 struct{}
+type E2[_ any] struct{}
+
+func (E1) M() int { return 0 }
+func (*E2[_]) N() int { return 1 }
diff --git a/go/test/typeparam/mdempsky/21.go b/go/test/typeparam/mdempsky/21.go
new file mode 100644
index 0000000000000000000000000000000000000000..da10ae3ea329889c75552360673ca15ef1ceea8e
--- /dev/null
+++ b/go/test/typeparam/mdempsky/21.go
@@ -0,0 +1,26 @@
+// run
+
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test that devirtualization doesn't introduce spurious type
+// assertion failures due to shaped and non-shaped interfaces having
+// distinct itabs.
+
+package main
+
+func main() {
+ F[int]()
+}
+
+func F[T any]() {
+ var i I[T] = X(0)
+ i.M()
+}
+
+type I[T any] interface{ M() }
+
+type X int
+
+func (X) M() {}
diff --git a/go/test/typeparam/mdempsky/3.dir/a.go b/go/test/typeparam/mdempsky/3.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..cf456e8d48f17422ebb16183066d6556f371f04e
--- /dev/null
+++ b/go/test/typeparam/mdempsky/3.dir/a.go
@@ -0,0 +1,7 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func F[T interface{ chan int }](c T) {}
diff --git a/go/test/typeparam/mdempsky/3.dir/b.go b/go/test/typeparam/mdempsky/3.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..0cfd142f4c454e8222253d97e5a48cab273580d5
--- /dev/null
+++ b/go/test/typeparam/mdempsky/3.dir/b.go
@@ -0,0 +1,9 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func g() { a.F(make(chan int)) }
diff --git a/go/test/typeparam/mdempsky/3.go b/go/test/typeparam/mdempsky/3.go
new file mode 100644
index 0000000000000000000000000000000000000000..b83fbd7af16a576c16e0fc73b84f1ca0f618b756
--- /dev/null
+++ b/go/test/typeparam/mdempsky/3.go
@@ -0,0 +1,7 @@
+// compiledir
+
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ignored
diff --git a/go/test/typeparam/mdempsky/4.dir/a.go b/go/test/typeparam/mdempsky/4.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..cb672949eaedcd8faaeb72beb135078c6de41a7e
--- /dev/null
+++ b/go/test/typeparam/mdempsky/4.dir/a.go
@@ -0,0 +1,12 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func F[T any](T) {
+Loop:
+ for {
+ break Loop
+ }
+}
diff --git a/go/test/typeparam/mdempsky/4.dir/b.go b/go/test/typeparam/mdempsky/4.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..e1fb0e7c5eaabc3af41c320fe9adfda6a22e7eab
--- /dev/null
+++ b/go/test/typeparam/mdempsky/4.dir/b.go
@@ -0,0 +1,9 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func f() { a.F(0) }
diff --git a/go/test/typeparam/mdempsky/4.go b/go/test/typeparam/mdempsky/4.go
new file mode 100644
index 0000000000000000000000000000000000000000..b83fbd7af16a576c16e0fc73b84f1ca0f618b756
--- /dev/null
+++ b/go/test/typeparam/mdempsky/4.go
@@ -0,0 +1,7 @@
+// compiledir
+
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ignored
diff --git a/go/test/typeparam/mdempsky/5.go b/go/test/typeparam/mdempsky/5.go
new file mode 100644
index 0000000000000000000000000000000000000000..00d3b71be0ee53f71e4482b4dd7fb46fb0681e87
--- /dev/null
+++ b/go/test/typeparam/mdempsky/5.go
@@ -0,0 +1,15 @@
+// compile
+
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type X[T any] int
+
+func (X[T]) F(T) {}
+
+func x() {
+ X[interface{}](0).F(0)
+}
diff --git a/go/test/typeparam/mdempsky/6.go b/go/test/typeparam/mdempsky/6.go
new file mode 100644
index 0000000000000000000000000000000000000000..ed57009436850f1c59335f8c442cb45b2c10549c
--- /dev/null
+++ b/go/test/typeparam/mdempsky/6.go
@@ -0,0 +1,11 @@
+// compile
+
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type I[T any] interface{ M() T }
+
+var _ = I[int].M
diff --git a/go/test/typeparam/mdempsky/7.dir/a.go b/go/test/typeparam/mdempsky/7.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..59c5995611834a9cbec9ca3b2aa9f9588011ea36
--- /dev/null
+++ b/go/test/typeparam/mdempsky/7.dir/a.go
@@ -0,0 +1,9 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type I[T any] interface{ M() T }
+
+var X I[int]
diff --git a/go/test/typeparam/mdempsky/7.dir/b.go b/go/test/typeparam/mdempsky/7.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..9f70530811482ea8213ec47efd5f76593a432814
--- /dev/null
+++ b/go/test/typeparam/mdempsky/7.dir/b.go
@@ -0,0 +1,9 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+var _ = a.X
diff --git a/go/test/typeparam/mdempsky/7.go b/go/test/typeparam/mdempsky/7.go
new file mode 100644
index 0000000000000000000000000000000000000000..b83fbd7af16a576c16e0fc73b84f1ca0f618b756
--- /dev/null
+++ b/go/test/typeparam/mdempsky/7.go
@@ -0,0 +1,7 @@
+// compiledir
+
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ignored
diff --git a/go/test/typeparam/mdempsky/8.dir/a.go b/go/test/typeparam/mdempsky/8.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..607fe5e0af2e098b1083bbe81c12c3f7dfa58506
--- /dev/null
+++ b/go/test/typeparam/mdempsky/8.dir/a.go
@@ -0,0 +1,7 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func F[T interface{ comparable }]() {}
diff --git a/go/test/typeparam/mdempsky/8.dir/b.go b/go/test/typeparam/mdempsky/8.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..ef2637b894fb69c563689081f44dc3f431a9ee5d
--- /dev/null
+++ b/go/test/typeparam/mdempsky/8.dir/b.go
@@ -0,0 +1,11 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func init() {
+ a.F[func()]() // ERROR "does not satisfy comparable"
+}
diff --git a/go/test/typeparam/mdempsky/8.go b/go/test/typeparam/mdempsky/8.go
new file mode 100644
index 0000000000000000000000000000000000000000..e3a470b4195ab9ee0b49030efa76975b00b284f7
--- /dev/null
+++ b/go/test/typeparam/mdempsky/8.go
@@ -0,0 +1,7 @@
+// errorcheckdir
+
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ignored
diff --git a/go/test/typeparam/mdempsky/9.go b/go/test/typeparam/mdempsky/9.go
new file mode 100644
index 0000000000000000000000000000000000000000..948a9e532e0c7661cdacdd36a5a65dfc7a544798
--- /dev/null
+++ b/go/test/typeparam/mdempsky/9.go
@@ -0,0 +1,11 @@
+// compile
+
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func f[V any]() []V { return []V{0: *new(V)} }
+
+func g() { f[int]() }
diff --git a/go/test/typeparam/mincheck.dir/a.go b/go/test/typeparam/mincheck.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..fa0f249e61510c3a136fc0c66b3cff4d3f876df0
--- /dev/null
+++ b/go/test/typeparam/mincheck.dir/a.go
@@ -0,0 +1,16 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type Ordered interface {
+ int | int64 | float64
+}
+
+func Min[T Ordered](x, y T) T {
+ if x < y {
+ return x
+ }
+ return y
+}
diff --git a/go/test/typeparam/mincheck.dir/main.go b/go/test/typeparam/mincheck.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..6f85f9e5e12bf0514a10633ed34c07b06d193e42
--- /dev/null
+++ b/go/test/typeparam/mincheck.dir/main.go
@@ -0,0 +1,38 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./a"
+ "fmt"
+)
+
+func main() {
+ const want = 2
+ if got := a.Min[int](2, 3); got != want {
+ panic(fmt.Sprintf("got %d, want %d", got, want))
+ }
+
+ if got := a.Min(2, 3); got != want {
+ panic(fmt.Sprintf("want %d, got %d", want, got))
+ }
+
+ if got := a.Min[float64](3.5, 2.0); got != want {
+ panic(fmt.Sprintf("got %d, want %d", got, want))
+ }
+
+ if got := a.Min(3.5, 2.0); got != want {
+ panic(fmt.Sprintf("got %d, want %d", got, want))
+ }
+
+ const want2 = "ay"
+ if got := a.Min[string]("bb", "ay"); got != want2 { // ERROR "string does not satisfy"
+ panic(fmt.Sprintf("got %d, want %d", got, want2))
+ }
+
+ if got := a.Min("bb", "ay"); got != want2 { // ERROR "string does not satisfy"
+ panic(fmt.Sprintf("got %d, want %d", got, want2))
+ }
+}
diff --git a/go/test/typeparam/minimp.dir/a.go b/go/test/typeparam/minimp.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..fabde62c5d7218c987cbd64793586c941456451c
--- /dev/null
+++ b/go/test/typeparam/minimp.dir/a.go
@@ -0,0 +1,16 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type Ordered interface {
+ ~int | ~int64 | ~float64 | ~string
+}
+
+func Min[T Ordered](x, y T) T {
+ if x < y {
+ return x
+ }
+ return y
+}
diff --git a/go/test/typeparam/minimp.dir/main.go b/go/test/typeparam/minimp.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..36bec0f600de2dea6b1ab763b56a9e758c9b7405
--- /dev/null
+++ b/go/test/typeparam/minimp.dir/main.go
@@ -0,0 +1,38 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./a"
+ "fmt"
+)
+
+func main() {
+ const want = 2
+ if got := a.Min[int](2, 3); got != want {
+ panic(fmt.Sprintf("got %d, want %d", got, want))
+ }
+
+ if got := a.Min(2, 3); got != want {
+ panic(fmt.Sprintf("want %d, got %d", want, got))
+ }
+
+ if got := a.Min[float64](3.5, 2.0); got != want {
+ panic(fmt.Sprintf("got %d, want %d", got, want))
+ }
+
+ if got := a.Min(3.5, 2.0); got != want {
+ panic(fmt.Sprintf("got %d, want %d", got, want))
+ }
+
+ const want2 = "ay"
+ if got := a.Min[string]("bb", "ay"); got != want2 {
+ panic(fmt.Sprintf("got %d, want %d", got, want2))
+ }
+
+ if got := a.Min("bb", "ay"); got != want2 {
+ panic(fmt.Sprintf("got %d, want %d", got, want2))
+ }
+}
diff --git a/go/test/typeparam/mutualimp.dir/a.go b/go/test/typeparam/mutualimp.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..5b924d3ce5dfec687d84c11e0bcf7b145493abcb
--- /dev/null
+++ b/go/test/typeparam/mutualimp.dir/a.go
@@ -0,0 +1,12 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type X int
+
+func (x X) M() X { return x }
+
+func F[T interface{ M() U }, U interface{ M() T }]() {}
+func G() { F[X, X]() }
diff --git a/go/test/typeparam/mutualimp.dir/b.go b/go/test/typeparam/mutualimp.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..83cc3af2835c55b7c1b5db2ba604d9a5b2da05e8
--- /dev/null
+++ b/go/test/typeparam/mutualimp.dir/b.go
@@ -0,0 +1,12 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func H() {
+ a.F[a.X, a.X]()
+ a.G()
+}
diff --git a/go/test/typeparam/orderedmapsimp.dir/a.go b/go/test/typeparam/orderedmapsimp.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..d6a2de5d7b3e4a7eead46e360ac9a9c04b1293a1
--- /dev/null
+++ b/go/test/typeparam/orderedmapsimp.dir/a.go
@@ -0,0 +1,226 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+import (
+ "context"
+ "runtime"
+)
+
+type Ordered interface {
+ ~int | ~int8 | ~int16 | ~int32 | ~int64 |
+ ~uint | ~uint8 | ~uint16 | ~uint32 | ~uint64 | ~uintptr |
+ ~float32 | ~float64 |
+ ~string
+}
+
+// Map is an ordered map.
+type Map[K, V any] struct {
+ root *node[K, V]
+ compare func(K, K) int
+}
+
+// node is the type of a node in the binary tree.
+type node[K, V any] struct {
+ key K
+ val V
+ left, right *node[K, V]
+}
+
+// New returns a new map. It takes a comparison function that compares two
+// keys and returns < 0 if the first is less, == 0 if they are equal,
+// > 0 if the first is greater.
+func New[K, V any](compare func(K, K) int) *Map[K, V] {
+ return &Map[K, V]{compare: compare}
+}
+
+// NewOrdered returns a new map whose key is an ordered type.
+// This is like New, but does not require providing a compare function.
+// The map compare function uses the obvious key ordering.
+func NewOrdered[K Ordered, V any]() *Map[K, V] {
+ return New[K, V](func(k1, k2 K) int {
+ switch {
+ case k1 < k2:
+ return -1
+ case k1 > k2:
+ return 1
+ default:
+ return 0
+ }
+ })
+}
+
+// find looks up key in the map, returning either a pointer to the slot of the
+// node holding key, or a pointer to the slot where a node would go.
+func (m *Map[K, V]) find(key K) **node[K, V] {
+ pn := &m.root
+ for *pn != nil {
+ switch cmp := m.compare(key, (*pn).key); {
+ case cmp < 0:
+ pn = &(*pn).left
+ case cmp > 0:
+ pn = &(*pn).right
+ default:
+ return pn
+ }
+ }
+ return pn
+}
+
+// Insert inserts a new key/value into the map.
+// If the key is already present, the value is replaced.
+// Reports whether this is a new key.
+func (m *Map[K, V]) Insert(key K, val V) bool {
+ pn := m.find(key)
+ if *pn != nil {
+ (*pn).val = val
+ return false
+ }
+ *pn = &node[K, V]{key: key, val: val}
+ return true
+}
+
+// Find returns the value associated with a key, or the zero value
+// if not present. The second result reports whether the key was found.
+func (m *Map[K, V]) Find(key K) (V, bool) {
+ pn := m.find(key)
+ if *pn == nil {
+ var zero V
+ return zero, false
+ }
+ return (*pn).val, true
+}
+
+// keyValue is a pair of key and value used while iterating.
+type keyValue[K, V any] struct {
+ key K
+ val V
+}
+
+// iterate returns an iterator that traverses the map.
+func (m *Map[K, V]) Iterate() *Iterator[K, V] {
+ sender, receiver := Ranger[keyValue[K, V]]()
+ var f func(*node[K, V]) bool
+ f = func(n *node[K, V]) bool {
+ if n == nil {
+ return true
+ }
+ // Stop the traversal if Send fails, which means that
+ // nothing is listening to the receiver.
+ return f(n.left) &&
+ sender.Send(context.Background(), keyValue[K, V]{n.key, n.val}) &&
+ f(n.right)
+ }
+ go func() {
+ f(m.root)
+ sender.Close()
+ }()
+ return &Iterator[K, V]{receiver}
+}
+
+// Iterator is used to iterate over the map.
+type Iterator[K, V any] struct {
+ r *Receiver[keyValue[K, V]]
+}
+
+// Next returns the next key and value pair, and a boolean that reports
+// whether they are valid. If not valid, we have reached the end of the map.
+func (it *Iterator[K, V]) Next() (K, V, bool) {
+ keyval, ok := it.r.Next(context.Background())
+ if !ok {
+ var zerok K
+ var zerov V
+ return zerok, zerov, false
+ }
+ return keyval.key, keyval.val, true
+}
+
+// Equal reports whether two slices are equal: the same length and all
+// elements equal. All floating point NaNs are considered equal.
+func SliceEqual[Elem comparable](s1, s2 []Elem) bool {
+ if len(s1) != len(s2) {
+ return false
+ }
+ for i, v1 := range s1 {
+ v2 := s2[i]
+ if v1 != v2 {
+ isNaN := func(f Elem) bool { return f != f }
+ if !isNaN(v1) || !isNaN(v2) {
+ return false
+ }
+ }
+ }
+ return true
+}
+
+// Ranger returns a Sender and a Receiver. The Receiver provides a
+// Next method to retrieve values. The Sender provides a Send method
+// to send values and a Close method to stop sending values. The Next
+// method indicates when the Sender has been closed, and the Send
+// method indicates when the Receiver has been freed.
+//
+// This is a convenient way to exit a goroutine sending values when
+// the receiver stops reading them.
+func Ranger[Elem any]() (*Sender[Elem], *Receiver[Elem]) {
+ c := make(chan Elem)
+ d := make(chan struct{})
+ s := &Sender[Elem]{
+ values: c,
+ done: d,
+ }
+ r := &Receiver[Elem]{
+ values: c,
+ done: d,
+ }
+ runtime.SetFinalizer(r, (*Receiver[Elem]).finalize)
+ return s, r
+}
+
+// A Sender is used to send values to a Receiver.
+type Sender[Elem any] struct {
+ values chan<- Elem
+ done <-chan struct{}
+}
+
+// Send sends a value to the receiver. It reports whether the value was sent.
+// The value will not be sent if the context is closed or the receiver
+// is freed.
+func (s *Sender[Elem]) Send(ctx context.Context, v Elem) bool {
+ select {
+ case <-ctx.Done():
+ return false
+ case s.values <- v:
+ return true
+ case <-s.done:
+ return false
+ }
+}
+
+// Close tells the receiver that no more values will arrive.
+// After Close is called, the Sender may no longer be used.
+func (s *Sender[Elem]) Close() {
+ close(s.values)
+}
+
+// A Receiver receives values from a Sender.
+type Receiver[Elem any] struct {
+ values <-chan Elem
+ done chan<- struct{}
+}
+
+// Next returns the next value from the channel. The bool result indicates
+// whether the value is valid.
+func (r *Receiver[Elem]) Next(ctx context.Context) (v Elem, ok bool) {
+ select {
+ case <-ctx.Done():
+ case v, ok = <-r.values:
+ }
+ return v, ok
+}
+
+// finalize is a finalizer for the receiver.
+func (r *Receiver[Elem]) finalize() {
+ close(r.done)
+}
diff --git a/go/test/typeparam/orderedmapsimp.dir/main.go b/go/test/typeparam/orderedmapsimp.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..7758a75c233776aad8ea0e118b55a7536ea50d76
--- /dev/null
+++ b/go/test/typeparam/orderedmapsimp.dir/main.go
@@ -0,0 +1,64 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./a"
+ "bytes"
+ "fmt"
+)
+
+func TestMap() {
+ m := a.New[[]byte, int](bytes.Compare)
+
+ if _, found := m.Find([]byte("a")); found {
+ panic(fmt.Sprintf("unexpectedly found %q in empty map", []byte("a")))
+ }
+
+ for _, c := range []int{'a', 'c', 'b'} {
+ if !m.Insert([]byte(string(c)), c) {
+ panic(fmt.Sprintf("key %q unexpectedly already present", []byte(string(c))))
+ }
+ }
+ if m.Insert([]byte("c"), 'x') {
+ panic(fmt.Sprintf("key %q unexpectedly not present", []byte("c")))
+ }
+
+ if v, found := m.Find([]byte("a")); !found {
+ panic(fmt.Sprintf("did not find %q", []byte("a")))
+ } else if v != 'a' {
+ panic(fmt.Sprintf("key %q returned wrong value %c, expected %c", []byte("a"), v, 'a'))
+ }
+ if v, found := m.Find([]byte("c")); !found {
+ panic(fmt.Sprintf("did not find %q", []byte("c")))
+ } else if v != 'x' {
+ panic(fmt.Sprintf("key %q returned wrong value %c, expected %c", []byte("c"), v, 'x'))
+ }
+
+ if _, found := m.Find([]byte("d")); found {
+ panic(fmt.Sprintf("unexpectedly found %q", []byte("d")))
+ }
+
+ gather := func(it *a.Iterator[[]byte, int]) []int {
+ var r []int
+ for {
+ _, v, ok := it.Next()
+ if !ok {
+ return r
+ }
+ r = append(r, v)
+ }
+ }
+ got := gather(m.Iterate())
+ want := []int{'a', 'b', 'x'}
+ if !a.SliceEqual(got, want) {
+ panic(fmt.Sprintf("Iterate returned %v, want %v", got, want))
+ }
+
+}
+
+func main() {
+ TestMap()
+}
diff --git a/go/test/typeparam/pairimp.dir/a.go b/go/test/typeparam/pairimp.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..a984fba37b6e6655d8ba2031166d7b575737927c
--- /dev/null
+++ b/go/test/typeparam/pairimp.dir/a.go
@@ -0,0 +1,10 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type Pair[F1, F2 any] struct {
+ Field1 F1
+ Field2 F2
+}
diff --git a/go/test/typeparam/pairimp.dir/main.go b/go/test/typeparam/pairimp.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..f76da434d4cfe34deaf4534df90f5d1bd101e9cd
--- /dev/null
+++ b/go/test/typeparam/pairimp.dir/main.go
@@ -0,0 +1,30 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./a"
+ "fmt"
+ "unsafe"
+)
+
+func main() {
+ p := a.Pair[int32, int64]{1, 2}
+ if got, want := unsafe.Sizeof(p.Field1), uintptr(4); got != want {
+ panic(fmt.Sprintf("unexpected f1 size == %d, want %d", got, want))
+ }
+ if got, want := unsafe.Sizeof(p.Field2), uintptr(8); got != want {
+ panic(fmt.Sprintf("unexpected f2 size == %d, want %d", got, want))
+ }
+
+ type mypair struct {
+ Field1 int32
+ Field2 int64
+ }
+ mp := mypair(p)
+ if mp.Field1 != 1 || mp.Field2 != 2 {
+ panic(fmt.Sprintf("mp == %#v, want %#v", mp, mypair{1, 2}))
+ }
+}
diff --git a/go/test/typeparam/recoverimp.dir/a.go b/go/test/typeparam/recoverimp.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..a465fd1545fe9deda77d80575f100b4af9d60d30
--- /dev/null
+++ b/go/test/typeparam/recoverimp.dir/a.go
@@ -0,0 +1,16 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+import "fmt"
+
+func F[T any](a T) {
+ defer func() {
+ if x := recover(); x != nil {
+ fmt.Printf("panic: %v\n", x)
+ }
+ }()
+ panic(a)
+}
diff --git a/go/test/typeparam/recoverimp.dir/main.go b/go/test/typeparam/recoverimp.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..d8cfa3875c0b5e69208e9253edb4b0b8388b5950
--- /dev/null
+++ b/go/test/typeparam/recoverimp.dir/main.go
@@ -0,0 +1,12 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./a"
+
+func main() {
+ a.F(5.3)
+ a.F("hello")
+}
diff --git a/go/test/typeparam/select.dir/a.go b/go/test/typeparam/select.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..983e4b1d5f7cd8c4deb00ce7a43893fb4b09a3e2
--- /dev/null
+++ b/go/test/typeparam/select.dir/a.go
@@ -0,0 +1,15 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+func F[T any](c, d chan T) T {
+ select {
+ case x := <- c:
+ return x
+ case x := <- d:
+ return x
+ }
+}
+
diff --git a/go/test/typeparam/select.dir/main.go b/go/test/typeparam/select.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..6ea3fe2eeac3a4b54e0175211a996aca02e34cec
--- /dev/null
+++ b/go/test/typeparam/select.dir/main.go
@@ -0,0 +1,28 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "sort"
+
+ "./a"
+)
+
+func main() {
+ c := make(chan int, 1)
+ d := make(chan int, 1)
+
+ c <- 5
+ d <- 6
+
+ var r [2]int
+ r[0] = a.F(c, d)
+ r[1] = a.F(c, d)
+ sort.Ints(r[:])
+
+ if r != [2]int{5, 6} {
+ panic("incorrect results")
+ }
+}
diff --git a/go/test/typeparam/setsimp.dir/a.go b/go/test/typeparam/setsimp.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..92449ce95620caf19ee17019ddecf36c8130ea89
--- /dev/null
+++ b/go/test/typeparam/setsimp.dir/a.go
@@ -0,0 +1,128 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+// SliceEqual reports whether two slices are equal: the same length and all
+// elements equal. All floating point NaNs are considered equal.
+func SliceEqual[Elem comparable](s1, s2 []Elem) bool {
+ if len(s1) != len(s2) {
+ return false
+ }
+ for i, v1 := range s1 {
+ v2 := s2[i]
+ if v1 != v2 {
+ isNaN := func(f Elem) bool { return f != f }
+ if !isNaN(v1) || !isNaN(v2) {
+ return false
+ }
+ }
+ }
+ return true
+}
+
+// A Set is a set of elements of some type.
+type Set[Elem comparable] struct {
+ m map[Elem]struct{}
+}
+
+// Make makes a new set.
+func Make[Elem comparable]() Set[Elem] {
+ return Set[Elem]{m: make(map[Elem]struct{})}
+}
+
+// Add adds an element to a set.
+func (s Set[Elem]) Add(v Elem) {
+ s.m[v] = struct{}{}
+}
+
+// Delete removes an element from a set. If the element is not present
+// in the set, this does nothing.
+func (s Set[Elem]) Delete(v Elem) {
+ delete(s.m, v)
+}
+
+// Contains reports whether v is in the set.
+func (s Set[Elem]) Contains(v Elem) bool {
+ _, ok := s.m[v]
+ return ok
+}
+
+// Len returns the number of elements in the set.
+func (s Set[Elem]) Len() int {
+ return len(s.m)
+}
+
+// Values returns the values in the set.
+// The values will be in an indeterminate order.
+func (s Set[Elem]) Values() []Elem {
+ r := make([]Elem, 0, len(s.m))
+ for v := range s.m {
+ r = append(r, v)
+ }
+ return r
+}
+
+// Equal reports whether two sets contain the same elements.
+func Equal[Elem comparable](s1, s2 Set[Elem]) bool {
+ if len(s1.m) != len(s2.m) {
+ return false
+ }
+ for v1 := range s1.m {
+ if !s2.Contains(v1) {
+ return false
+ }
+ }
+ return true
+}
+
+// Copy returns a copy of s.
+func (s Set[Elem]) Copy() Set[Elem] {
+ r := Set[Elem]{m: make(map[Elem]struct{}, len(s.m))}
+ for v := range s.m {
+ r.m[v] = struct{}{}
+ }
+ return r
+}
+
+// AddSet adds all the elements of s2 to s.
+func (s Set[Elem]) AddSet(s2 Set[Elem]) {
+ for v := range s2.m {
+ s.m[v] = struct{}{}
+ }
+}
+
+// SubSet removes all elements in s2 from s.
+// Values in s2 that are not in s are ignored.
+func (s Set[Elem]) SubSet(s2 Set[Elem]) {
+ for v := range s2.m {
+ delete(s.m, v)
+ }
+}
+
+// Intersect removes all elements from s that are not present in s2.
+// Values in s2 that are not in s are ignored.
+func (s Set[Elem]) Intersect(s2 Set[Elem]) {
+ for v := range s.m {
+ if !s2.Contains(v) {
+ delete(s.m, v)
+ }
+ }
+}
+
+// Iterate calls f on every element in the set.
+func (s Set[Elem]) Iterate(f func(Elem)) {
+ for v := range s.m {
+ f(v)
+ }
+}
+
+// Filter deletes any elements from s for which f returns false.
+func (s Set[Elem]) Filter(f func(Elem) bool) {
+ for v := range s.m {
+ if !f(v) {
+ delete(s.m, v)
+ }
+ }
+}
diff --git a/go/test/typeparam/setsimp.dir/main.go b/go/test/typeparam/setsimp.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..e1ec86a6f0d030f43955977c18e814d5265649b1
--- /dev/null
+++ b/go/test/typeparam/setsimp.dir/main.go
@@ -0,0 +1,156 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./a"
+ "fmt"
+ "sort"
+)
+
+func TestSet() {
+ s1 := a.Make[int]()
+ if got := s1.Len(); got != 0 {
+ panic(fmt.Sprintf("Len of empty set = %d, want 0", got))
+ }
+ s1.Add(1)
+ s1.Add(1)
+ s1.Add(1)
+ if got := s1.Len(); got != 1 {
+ panic(fmt.Sprintf("(%v).Len() == %d, want 1", s1, got))
+ }
+ s1.Add(2)
+ s1.Add(3)
+ s1.Add(4)
+ if got := s1.Len(); got != 4 {
+ panic(fmt.Sprintf("(%v).Len() == %d, want 4", s1, got))
+ }
+ if !s1.Contains(1) {
+ panic(fmt.Sprintf("(%v).Contains(1) == false, want true", s1))
+ }
+ if s1.Contains(5) {
+ panic(fmt.Sprintf("(%v).Contains(5) == true, want false", s1))
+ }
+ vals := s1.Values()
+ sort.Ints(vals)
+ w1 := []int{1, 2, 3, 4}
+ if !a.SliceEqual(vals, w1) {
+ panic(fmt.Sprintf("(%v).Values() == %v, want %v", s1, vals, w1))
+ }
+}
+
+func TestEqual() {
+ s1 := a.Make[string]()
+ s2 := a.Make[string]()
+ if !a.Equal(s1, s2) {
+ panic(fmt.Sprintf("a.Equal(%v, %v) = false, want true", s1, s2))
+ }
+ s1.Add("hello")
+ s1.Add("world")
+ if got := s1.Len(); got != 2 {
+ panic(fmt.Sprintf("(%v).Len() == %d, want 2", s1, got))
+ }
+ if a.Equal(s1, s2) {
+ panic(fmt.Sprintf("a.Equal(%v, %v) = true, want false", s1, s2))
+ }
+}
+
+func TestCopy() {
+ s1 := a.Make[float64]()
+ s1.Add(0)
+ s2 := s1.Copy()
+ if !a.Equal(s1, s2) {
+ panic(fmt.Sprintf("a.Equal(%v, %v) = false, want true", s1, s2))
+ }
+ s1.Add(1)
+ if a.Equal(s1, s2) {
+ panic(fmt.Sprintf("a.Equal(%v, %v) = true, want false", s1, s2))
+ }
+}
+
+func TestAddSet() {
+ s1 := a.Make[int]()
+ s1.Add(1)
+ s1.Add(2)
+ s2 := a.Make[int]()
+ s2.Add(2)
+ s2.Add(3)
+ s1.AddSet(s2)
+ if got := s1.Len(); got != 3 {
+ panic(fmt.Sprintf("(%v).Len() == %d, want 3", s1, got))
+ }
+ s2.Add(1)
+ if !a.Equal(s1, s2) {
+ panic(fmt.Sprintf("a.Equal(%v, %v) = false, want true", s1, s2))
+ }
+}
+
+func TestSubSet() {
+ s1 := a.Make[int]()
+ s1.Add(1)
+ s1.Add(2)
+ s2 := a.Make[int]()
+ s2.Add(2)
+ s2.Add(3)
+ s1.SubSet(s2)
+ if got := s1.Len(); got != 1 {
+ panic(fmt.Sprintf("(%v).Len() == %d, want 1", s1, got))
+ }
+ if vals, want := s1.Values(), []int{1}; !a.SliceEqual(vals, want) {
+ panic(fmt.Sprintf("after SubSet got %v, want %v", vals, want))
+ }
+}
+
+func TestIntersect() {
+ s1 := a.Make[int]()
+ s1.Add(1)
+ s1.Add(2)
+ s2 := a.Make[int]()
+ s2.Add(2)
+ s2.Add(3)
+ s1.Intersect(s2)
+ if got := s1.Len(); got != 1 {
+ panic(fmt.Sprintf("(%v).Len() == %d, want 1", s1, got))
+ }
+ if vals, want := s1.Values(), []int{2}; !a.SliceEqual(vals, want) {
+ panic(fmt.Sprintf("after Intersect got %v, want %v", vals, want))
+ }
+}
+
+func TestIterate() {
+ s1 := a.Make[int]()
+ s1.Add(1)
+ s1.Add(2)
+ s1.Add(3)
+ s1.Add(4)
+ tot := 0
+ s1.Iterate(func(i int) { tot += i })
+ if tot != 10 {
+ panic(fmt.Sprintf("total of %v == %d, want 10", s1, tot))
+ }
+}
+
+func TestFilter() {
+ s1 := a.Make[int]()
+ s1.Add(1)
+ s1.Add(2)
+ s1.Add(3)
+ s1.Filter(func(v int) bool { return v%2 == 0 })
+ if vals, want := s1.Values(), []int{2}; !a.SliceEqual(vals, want) {
+ panic(fmt.Sprintf("after Filter got %v, want %v", vals, want))
+ }
+
+}
+
+func main() {
+ TestSet()
+ TestEqual()
+ TestCopy()
+ TestAddSet()
+ TestSubSet()
+ TestIntersect()
+ TestIterate()
+ TestFilter()
+}
diff --git a/go/test/typeparam/sliceimp.dir/a.go b/go/test/typeparam/sliceimp.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..dbcfae893185e3b9f2e07f1060c523c0c48b3155
--- /dev/null
+++ b/go/test/typeparam/sliceimp.dir/a.go
@@ -0,0 +1,141 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type Ordered interface {
+ ~int | ~int8 | ~int16 | ~int32 | ~int64 |
+ ~uint | ~uint8 | ~uint16 | ~uint32 | ~uint64 | ~uintptr |
+ ~float32 | ~float64 |
+ ~string
+}
+
+// Max returns the maximum of two values of some ordered type.
+func Max[T Ordered](a, b T) T {
+ if a > b {
+ return a
+ }
+ return b
+}
+
+// Min returns the minimum of two values of some ordered type.
+func Min[T Ordered](a, b T) T {
+ if a < b {
+ return a
+ }
+ return b
+}
+
+// Equal reports whether two slices are equal: the same length and all
+// elements equal. All floating point NaNs are considered equal.
+func Equal[Elem comparable](s1, s2 []Elem) bool {
+ if len(s1) != len(s2) {
+ return false
+ }
+ for i, v1 := range s1 {
+ v2 := s2[i]
+ if v1 != v2 {
+ isNaN := func(f Elem) bool { return f != f }
+ if !isNaN(v1) || !isNaN(v2) {
+ return false
+ }
+ }
+ }
+ return true
+}
+
+// EqualFn reports whether two slices are equal using a comparison
+// function on each element.
+func EqualFn[Elem any](s1, s2 []Elem, eq func(Elem, Elem) bool) bool {
+ if len(s1) != len(s2) {
+ return false
+ }
+ for i, v1 := range s1 {
+ v2 := s2[i]
+ if !eq(v1, v2) {
+ return false
+ }
+ }
+ return true
+}
+
+// Map turns a []Elem1 to a []Elem2 using a mapping function.
+func Map[Elem1, Elem2 any](s []Elem1, f func(Elem1) Elem2) []Elem2 {
+ r := make([]Elem2, len(s))
+ for i, v := range s {
+ r[i] = f(v)
+ }
+ return r
+}
+
+// Reduce reduces a []Elem1 to a single value of type Elem2 using
+// a reduction function.
+func Reduce[Elem1, Elem2 any](s []Elem1, initializer Elem2, f func(Elem2, Elem1) Elem2) Elem2 {
+ r := initializer
+ for _, v := range s {
+ r = f(r, v)
+ }
+ return r
+}
+
+// Filter filters values from a slice using a filter function.
+func Filter[Elem any](s []Elem, f func(Elem) bool) []Elem {
+ var r []Elem
+ for _, v := range s {
+ if f(v) {
+ r = append(r, v)
+ }
+ }
+ return r
+}
+
+// Max returns the maximum element in a slice of some ordered type.
+// If the slice is empty it returns the zero value of the element type.
+func SliceMax[Elem Ordered](s []Elem) Elem {
+ if len(s) == 0 {
+ var zero Elem
+ return zero
+ }
+ return Reduce(s[1:], s[0], Max[Elem])
+}
+
+// Min returns the minimum element in a slice of some ordered type.
+// If the slice is empty it returns the zero value of the element type.
+func SliceMin[Elem Ordered](s []Elem) Elem {
+ if len(s) == 0 {
+ var zero Elem
+ return zero
+ }
+ return Reduce(s[1:], s[0], Min[Elem])
+}
+
+// Append adds values to the end of a slice, returning a new slice.
+// This is like the predeclared append function; it's an example
+// of how to write it using generics. We used to write code like
+// this before append was added to the language, but we had to write
+// a separate copy for each type.
+func Append[T any](s []T, t ...T) []T {
+ lens := len(s)
+ tot := lens + len(t)
+ if tot <= cap(s) {
+ s = s[:tot]
+ } else {
+ news := make([]T, tot, tot+tot/2)
+ Copy(news, s)
+ s = news
+ }
+ Copy(s[lens:tot], t)
+ return s
+}
+
+// Copy copies values from t to s, stopping when either slice is full,
+// returning the number of values copied. This is like the predeclared
+// copy function; it's an example of how to write it using generics.
+func Copy[T any](s, t []T) int {
+ i := 0
+ for ; i < len(s) && i < len(t); i++ {
+ s[i] = t[i]
+ }
+ return i
+}
diff --git a/go/test/typeparam/sliceimp.dir/main.go b/go/test/typeparam/sliceimp.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..ec13188ba9654d3b1c0e0fd774c6792643542d4a
--- /dev/null
+++ b/go/test/typeparam/sliceimp.dir/main.go
@@ -0,0 +1,179 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./a"
+ "fmt"
+ "math"
+ "strings"
+)
+
+type Integer interface {
+ ~int | ~int8 | ~int16 | ~int32 | ~int64 |
+ ~uint | ~uint8 | ~uint16 | ~uint32 | ~uint64 | ~uintptr
+}
+
+func TestEqual() {
+ s1 := []int{1, 2, 3}
+ if !a.Equal(s1, s1) {
+ panic(fmt.Sprintf("a.Equal(%v, %v) = false, want true", s1, s1))
+ }
+ s2 := []int{1, 2, 3}
+ if !a.Equal(s1, s2) {
+ panic(fmt.Sprintf("a.Equal(%v, %v) = false, want true", s1, s2))
+ }
+ s2 = append(s2, 4)
+ if a.Equal(s1, s2) {
+ panic(fmt.Sprintf("a.Equal(%v, %v) = true, want false", s1, s2))
+ }
+
+ s3 := []float64{1, 2, math.NaN()}
+ if !a.Equal(s3, s3) {
+ panic(fmt.Sprintf("a.Equal(%v, %v) = false, want true", s3, s3))
+ }
+
+ if a.Equal(s1, nil) {
+ panic(fmt.Sprintf("a.Equal(%v, nil) = true, want false", s1))
+ }
+ if a.Equal(nil, s1) {
+ panic(fmt.Sprintf("a.Equal(nil, %v) = true, want false", s1))
+ }
+ if !a.Equal(s1[:0], nil) {
+ panic(fmt.Sprintf("a.Equal(%v, nil = false, want true", s1[:0]))
+ }
+}
+
+func offByOne[Elem Integer](a, b Elem) bool {
+ return a == b+1 || a == b-1
+}
+
+func TestEqualFn() {
+ s1 := []int{1, 2, 3}
+ s2 := []int{2, 3, 4}
+ if a.EqualFn(s1, s1, offByOne[int]) {
+ panic(fmt.Sprintf("a.EqualFn(%v, %v, offByOne) = true, want false", s1, s1))
+ }
+ if !a.EqualFn(s1, s2, offByOne[int]) {
+ panic(fmt.Sprintf("a.EqualFn(%v, %v, offByOne) = false, want true", s1, s2))
+ }
+
+ if !a.EqualFn(s1[:0], nil, offByOne[int]) {
+ panic(fmt.Sprintf("a.EqualFn(%v, nil, offByOne) = false, want true", s1[:0]))
+ }
+
+ s3 := []string{"a", "b", "c"}
+ s4 := []string{"A", "B", "C"}
+ if !a.EqualFn(s3, s4, strings.EqualFold) {
+ panic(fmt.Sprintf("a.EqualFn(%v, %v, strings.EqualFold) = false, want true", s3, s4))
+ }
+}
+
+func TestMap() {
+ s1 := []int{1, 2, 3}
+ s2 := a.Map(s1, func(i int) float64 { return float64(i) * 2.5 })
+ if want := []float64{2.5, 5, 7.5}; !a.Equal(s2, want) {
+ panic(fmt.Sprintf("a.Map(%v, ...) = %v, want %v", s1, s2, want))
+ }
+
+ s3 := []string{"Hello", "World"}
+ s4 := a.Map(s3, strings.ToLower)
+ if want := []string{"hello", "world"}; !a.Equal(s4, want) {
+ panic(fmt.Sprintf("a.Map(%v, strings.ToLower) = %v, want %v", s3, s4, want))
+ }
+
+ s5 := a.Map(nil, func(i int) int { return i })
+ if len(s5) != 0 {
+ panic(fmt.Sprintf("a.Map(nil, identity) = %v, want empty slice", s5))
+ }
+}
+
+func TestReduce() {
+ s1 := []int{1, 2, 3}
+ r := a.Reduce(s1, 0, func(f float64, i int) float64 { return float64(i)*2.5 + f })
+ if want := 15.0; r != want {
+ panic(fmt.Sprintf("a.Reduce(%v, 0, ...) = %v, want %v", s1, r, want))
+ }
+
+ if got := a.Reduce(nil, 0, func(i, j int) int { return i + j }); got != 0 {
+ panic(fmt.Sprintf("a.Reduce(nil, 0, add) = %v, want 0", got))
+ }
+}
+
+func TestFilter() {
+ s1 := []int{1, 2, 3}
+ s2 := a.Filter(s1, func(i int) bool { return i%2 == 0 })
+ if want := []int{2}; !a.Equal(s2, want) {
+ panic(fmt.Sprintf("a.Filter(%v, even) = %v, want %v", s1, s2, want))
+ }
+
+ if s3 := a.Filter(s1[:0], func(i int) bool { return true }); len(s3) > 0 {
+ panic(fmt.Sprintf("a.Filter(%v, identity) = %v, want empty slice", s1[:0], s3))
+ }
+}
+
+func TestMax() {
+ s1 := []int{1, 2, 3, -5}
+ if got, want := a.SliceMax(s1), 3; got != want {
+ panic(fmt.Sprintf("a.Max(%v) = %d, want %d", s1, got, want))
+ }
+
+ s2 := []string{"aaa", "a", "aa", "aaaa"}
+ if got, want := a.SliceMax(s2), "aaaa"; got != want {
+ panic(fmt.Sprintf("a.Max(%v) = %q, want %q", s2, got, want))
+ }
+
+ if got, want := a.SliceMax(s2[:0]), ""; got != want {
+ panic(fmt.Sprintf("a.Max(%v) = %q, want %q", s2[:0], got, want))
+ }
+}
+
+func TestMin() {
+ s1 := []int{1, 2, 3, -5}
+ if got, want := a.SliceMin(s1), -5; got != want {
+ panic(fmt.Sprintf("a.Min(%v) = %d, want %d", s1, got, want))
+ }
+
+ s2 := []string{"aaa", "a", "aa", "aaaa"}
+ if got, want := a.SliceMin(s2), "a"; got != want {
+ panic(fmt.Sprintf("a.Min(%v) = %q, want %q", s2, got, want))
+ }
+
+ if got, want := a.SliceMin(s2[:0]), ""; got != want {
+ panic(fmt.Sprintf("a.Min(%v) = %q, want %q", s2[:0], got, want))
+ }
+}
+
+func TestAppend() {
+ s := []int{1, 2, 3}
+ s = a.Append(s, 4, 5, 6)
+ want := []int{1, 2, 3, 4, 5, 6}
+ if !a.Equal(s, want) {
+ panic(fmt.Sprintf("after a.Append got %v, want %v", s, want))
+ }
+}
+
+func TestCopy() {
+ s1 := []int{1, 2, 3}
+ s2 := []int{4, 5}
+ if got := a.Copy(s1, s2); got != 2 {
+ panic(fmt.Sprintf("a.Copy returned %d, want 2", got))
+ }
+ want := []int{4, 5, 3}
+ if !a.Equal(s1, want) {
+ panic(fmt.Sprintf("after a.Copy got %v, want %v", s1, want))
+ }
+}
+func main() {
+ TestEqual()
+ TestEqualFn()
+ TestMap()
+ TestReduce()
+ TestFilter()
+ TestMax()
+ TestMin()
+ TestAppend()
+ TestCopy()
+}
diff --git a/go/test/typeparam/stringerimp.dir/a.go b/go/test/typeparam/stringerimp.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..3f70937ff55e862ed1fbf8dc206d830f56a97f59
--- /dev/null
+++ b/go/test/typeparam/stringerimp.dir/a.go
@@ -0,0 +1,16 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type Stringer interface {
+ String() string
+}
+
+func Stringify[T Stringer](s []T) (ret []string) {
+ for _, v := range s {
+ ret = append(ret, v.String())
+ }
+ return ret
+}
diff --git a/go/test/typeparam/stringerimp.dir/main.go b/go/test/typeparam/stringerimp.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..9b41d3bc1db010c996e69ea005d090651b6ca463
--- /dev/null
+++ b/go/test/typeparam/stringerimp.dir/main.go
@@ -0,0 +1,38 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./a"
+ "fmt"
+ "reflect"
+ "strconv"
+)
+
+type myint int
+
+func (i myint) String() string {
+ return strconv.Itoa(int(i))
+}
+
+func main() {
+ x := []myint{myint(1), myint(2), myint(3)}
+
+ got := a.Stringify(x)
+ want := []string{"1", "2", "3"}
+ if !reflect.DeepEqual(got, want) {
+ panic(fmt.Sprintf("got %s, want %s", got, want))
+ }
+
+ m1 := myint(1)
+ m2 := myint(2)
+ m3 := myint(3)
+ y := []*myint{&m1, &m2, &m3}
+ got2 := a.Stringify(y)
+ want2 := []string{"1", "2", "3"}
+ if !reflect.DeepEqual(got2, want2) {
+ panic(fmt.Sprintf("got %s, want %s", got2, want2))
+ }
+}
diff --git a/go/test/typeparam/structinit.dir/a.go b/go/test/typeparam/structinit.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..c76d1551adbeea9b19e3f500deac9405f0c64fc4
--- /dev/null
+++ b/go/test/typeparam/structinit.dir/a.go
@@ -0,0 +1,15 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type S[T any] struct {
+}
+
+func (b *S[T]) build() *X[T] {
+ return &X[T]{f:0}
+}
+type X[T any] struct {
+ f int
+}
diff --git a/go/test/typeparam/structinit.dir/b.go b/go/test/typeparam/structinit.dir/b.go
new file mode 100644
index 0000000000000000000000000000000000000000..40a929bcaede4af5d4a496b07de5c78565934b12
--- /dev/null
+++ b/go/test/typeparam/structinit.dir/b.go
@@ -0,0 +1,12 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package b
+
+import "./a"
+
+func B() {
+ var x a.S[int]
+ _ = x
+}
diff --git a/go/test/typeparam/structinit.dir/main.go b/go/test/typeparam/structinit.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..c564171879578c48318ee7284953e5f363fa8131
--- /dev/null
+++ b/go/test/typeparam/structinit.dir/main.go
@@ -0,0 +1,11 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "./b"
+
+func main() {
+ b.B()
+}
diff --git a/go/test/typeparam/valimp.dir/a.go b/go/test/typeparam/valimp.dir/a.go
new file mode 100644
index 0000000000000000000000000000000000000000..2ed0063cfd6473855a71a27e3327130ae6c553a2
--- /dev/null
+++ b/go/test/typeparam/valimp.dir/a.go
@@ -0,0 +1,32 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package a
+
+type Value[T any] struct {
+ val T
+}
+
+// The noinline directive should survive across import, and prevent instantiations
+// of these functions from being inlined.
+
+//go:noinline
+func Get[T any](v *Value[T]) T {
+ return v.val
+}
+
+//go:noinline
+func Set[T any](v *Value[T], val T) {
+ v.val = val
+}
+
+//go:noinline
+func (v *Value[T]) Set(val T) {
+ v.val = val
+}
+
+//go:noinline
+func (v *Value[T]) Get() T {
+ return v.val
+}
diff --git a/go/test/typeparam/valimp.dir/main.go b/go/test/typeparam/valimp.dir/main.go
new file mode 100644
index 0000000000000000000000000000000000000000..e357af4615f1ab74c623d640bb236fddc5723f79
--- /dev/null
+++ b/go/test/typeparam/valimp.dir/main.go
@@ -0,0 +1,55 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+ "./a"
+ "fmt"
+)
+
+func main() {
+ var v1 a.Value[int]
+
+ a.Set(&v1, 1)
+ if got, want := a.Get(&v1), 1; got != want {
+ panic(fmt.Sprintf("Get() == %d, want %d", got, want))
+ }
+ v1.Set(2)
+ if got, want := v1.Get(), 2; got != want {
+ panic(fmt.Sprintf("Get() == %d, want %d", got, want))
+ }
+ v1p := new(a.Value[int])
+ a.Set(v1p, 3)
+ if got, want := a.Get(v1p), 3; got != want {
+ panic(fmt.Sprintf("Get() == %d, want %d", got, want))
+ }
+
+ v1p.Set(4)
+ if got, want := v1p.Get(), 4; got != want {
+ panic(fmt.Sprintf("Get() == %d, want %d", got, want))
+ }
+
+ var v2 a.Value[string]
+ a.Set(&v2, "a")
+ if got, want := a.Get(&v2), "a"; got != want {
+ panic(fmt.Sprintf("Get() == %q, want %q", got, want))
+ }
+
+ v2.Set("b")
+ if got, want := a.Get(&v2), "b"; got != want {
+ panic(fmt.Sprintf("Get() == %q, want %q", got, want))
+ }
+
+ v2p := new(a.Value[string])
+ a.Set(v2p, "c")
+ if got, want := a.Get(v2p), "c"; got != want {
+ panic(fmt.Sprintf("Get() == %d, want %d", got, want))
+ }
+
+ v2p.Set("d")
+ if got, want := v2p.Get(), "d"; got != want {
+ panic(fmt.Sprintf("Get() == %d, want %d", got, want))
+ }
+}