File size: 3,566 Bytes
9adc280 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 | // 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 os
import (
"io"
"runtime"
"syscall"
"unsafe"
)
// Auxiliary information if the File describes a directory
type dirInfo struct {
dir uintptr // Pointer to DIR structure from dirent.h
}
func (d *dirInfo) close() {
if d.dir == 0 {
return
}
closedir(d.dir)
d.dir = 0
}
func (f *File) readdir(n int, mode readdirMode) (names []string, dirents []DirEntry, infos []FileInfo, err error) {
// If this file has no dirinfo, create one.
var d *dirInfo
for {
d = f.dirinfo.Load()
if d != nil {
break
}
dir, call, errno := f.pfd.OpenDir()
if errno != nil {
return nil, nil, nil, &PathError{Op: call, Path: f.name, Err: errno}
}
d = &dirInfo{dir: dir}
if f.dirinfo.CompareAndSwap(nil, d) {
break
}
// We lost the race: try again.
d.close()
}
size := n
if size <= 0 {
size = 100
n = -1
}
var dirent syscall.Dirent
var entptr *syscall.Dirent
for len(names)+len(dirents)+len(infos) < size || n == -1 {
if errno := readdir_r(d.dir, &dirent, &entptr); errno != 0 {
if errno == syscall.EINTR {
continue
}
return names, dirents, infos, &PathError{Op: "readdir", Path: f.name, Err: errno}
}
if entptr == nil { // EOF
break
}
// Darwin may return a zero inode when a directory entry has been
// deleted but not yet removed from the directory. The man page for
// getdirentries(2) states that programs are responsible for skipping
// those entries:
//
// Users of getdirentries() should skip entries with d_fileno = 0,
// as such entries represent files which have been deleted but not
// yet removed from the directory entry.
//
if dirent.Ino == 0 {
continue
}
name := (*[len(syscall.Dirent{}.Name)]byte)(unsafe.Pointer(&dirent.Name))[:]
for i, c := range name {
if c == 0 {
name = name[:i]
break
}
}
// Check for useless names before allocating a string.
if string(name) == "." || string(name) == ".." {
continue
}
if mode == readdirName {
names = append(names, string(name))
} else if mode == readdirDirEntry {
de, err := newUnixDirent(f, string(name), dtToType(dirent.Type))
if IsNotExist(err) {
// File disappeared between readdir and stat.
// Treat as if it didn't exist.
continue
}
if err != nil {
return nil, dirents, nil, err
}
dirents = append(dirents, de)
} else {
info, err := f.lstatat(string(name))
if IsNotExist(err) {
// File disappeared between readdir + stat.
// Treat as if it didn't exist.
continue
}
if err != nil {
return nil, nil, infos, err
}
infos = append(infos, info)
}
runtime.KeepAlive(f)
}
if n > 0 && len(names)+len(dirents)+len(infos) == 0 {
return nil, nil, nil, io.EOF
}
return names, dirents, infos, nil
}
func dtToType(typ uint8) FileMode {
switch typ {
case syscall.DT_BLK:
return ModeDevice
case syscall.DT_CHR:
return ModeDevice | ModeCharDevice
case syscall.DT_DIR:
return ModeDir
case syscall.DT_FIFO:
return ModeNamedPipe
case syscall.DT_LNK:
return ModeSymlink
case syscall.DT_REG:
return 0
case syscall.DT_SOCK:
return ModeSocket
}
return ^FileMode(0)
}
// Implemented in syscall/syscall_darwin.go.
//go:linkname closedir syscall.closedir
func closedir(dir uintptr) (err error)
//go:linkname readdir_r syscall.readdir_r
func readdir_r(dir uintptr, entry *syscall.Dirent, result **syscall.Dirent) (res syscall.Errno)
|