#include "../../unity/unity.h" #include #include #include #include #include #include #include /* Helper to read all bytes from fd into a malloc'd buffer. Returns buffer (null-terminated) and sets *out_len. */ static char *read_all_from_fd(int fd, size_t *out_len) { size_t cap = 1024; size_t len = 0; char *buf = (char *)malloc(cap + 1); if (!buf) return NULL; while (1) { if (len + 512 > cap) { cap *= 2; char *nb = (char *)realloc(buf, cap + 1); if (!nb) { free(buf); return NULL; } buf = nb; } ssize_t n = read(fd, buf + len, cap - len); if (n < 0) { if (errno == EINTR) continue; break; } if (n == 0) break; len += (size_t)n; } buf[len] = '\0'; if (out_len) *out_len = len; return buf; } /* Runs usage(status) in a child process with stdout/stderr captured. Sets LC_ALL=C, sets program name via set_program_name(progname). On success, returns 0 and fills outputs; on error returns -1. */ static int run_usage_and_capture(int status, const char *progname, char **out_buf, size_t *out_len, char **err_buf, size_t *err_len, int *exit_code) { int out_pipe[2]; int err_pipe[2]; if (pipe(out_pipe) < 0) return -1; if (pipe(err_pipe) < 0) { close(out_pipe[0]); close(out_pipe[1]); return -1; } fflush(stdout); fflush(stderr); pid_t pid = fork(); if (pid < 0) { close(out_pipe[0]); close(out_pipe[1]); close(err_pipe[0]); close(err_pipe[1]); return -1; } else if (pid == 0) { /* Child: redirect stdout/stderr to pipes, set locale and program name, call usage. */ if (dup2(out_pipe[1], STDOUT_FILENO) < 0) _exit(127); if (dup2(err_pipe[1], STDERR_FILENO) < 0) _exit(127); close(out_pipe[0]); close(out_pipe[1]); close(err_pipe[0]); close(err_pipe[1]); /* Force C locale to stabilize messages. */ setenv("LC_ALL", "C", 1); /* Ensure program_name is set. system.h should have included progname.h earlier. */ set_program_name(progname ? progname : "basename"); /* Call the function under test; it will exit(status). */ usage(status); /* Should not reach here. */ _exit(255); } else { /* Parent: close write ends, read from pipes, wait for child. */ close(out_pipe[1]); close(err_pipe[1]); char *o = read_all_from_fd(out_pipe[0], out_len); char *e = read_all_from_fd(err_pipe[0], err_len); close(out_pipe[0]); close(err_pipe[0]); int wstatus = 0; if (waitpid(pid, &wstatus, 0) < 0) { free(o); free(e); return -1; } int code = -1; if (WIFEXITED(wstatus)) code = WEXITSTATUS(wstatus); else if (WIFSIGNALED(wstatus)) code = 128 + WTERMSIG(wstatus); if (out_buf) *out_buf = o; else free(o); if (err_buf) *err_buf = e; else free(e); if (exit_code) *exit_code = code; return 0; } } /* Simple substring check. */ static int contains_substr(const char *hay, const char *needle) { if (!hay || !needle) return 0; return strstr(hay, needle) != NULL; } void setUp(void) { /* No global setup needed. */ } void tearDown(void) { /* No global teardown needed. */ } void test_usage_success_outputs_usage_and_exits_zero(void) { char *out = NULL, *err = NULL; size_t out_len = 0, err_len = 0; int code = -1; int rc = run_usage_and_capture(EXIT_SUCCESS, "basename", &out, &out_len, &err, &err_len, &code); TEST_ASSERT_EQUAL_INT(0, rc); TEST_ASSERT_EQUAL_INT(0, code); TEST_ASSERT_NOT_NULL(out); TEST_ASSERT_TRUE(out_len > 0); TEST_ASSERT_TRUE(contains_substr(out, "Usage: ")); TEST_ASSERT_TRUE(contains_substr(out, "NAME")); TEST_ASSERT_TRUE(contains_substr(out, "basename")); TEST_ASSERT_NOT_NULL(err); TEST_ASSERT_EQUAL_UINT64(0, (unsigned long long)err_len); free(out); free(err); } void test_usage_success_includes_options_and_examples(void) { char *out = NULL, *err = NULL; size_t out_len = 0, err_len = 0; int code = -1; int rc = run_usage_and_capture(EXIT_SUCCESS, "basename", &out, &out_len, &err, &err_len, &code); TEST_ASSERT_EQUAL_INT(0, rc); TEST_ASSERT_EQUAL_INT(0, code); TEST_ASSERT_TRUE(contains_substr(out, "-a, --multiple")); TEST_ASSERT_TRUE(contains_substr(out, "-s, --suffix")); TEST_ASSERT_TRUE(contains_substr(out, "-z, --zero")); TEST_ASSERT_TRUE(contains_substr(out, "Examples:")); free(out); free(err); } void test_usage_nonzero_status_exits_with_status_and_writes_stderr_only(void) { char *out = NULL, *err = NULL; size_t out_len = 0, err_len = 0; int code = -1; int rc = run_usage_and_capture(2, "basename", &out, &out_len, &err, &err_len, &code); TEST_ASSERT_EQUAL_INT(0, rc); TEST_ASSERT_EQUAL_INT(2, code); /* On error, full usage should not be printed to stdout. */ TEST_ASSERT_TRUE(out_len == 0 || !contains_substr(out, "Usage: ")); /* We expect some message on stderr. */ TEST_ASSERT_TRUE(err_len > 0); /* Likely message suggests --help. Under C locale, check for "--help". */ TEST_ASSERT_TRUE(contains_substr(err, "--help")); free(out); free(err); } void test_usage_respects_program_name_in_output(void) { /* Use a custom program name to confirm it appears in the usage text. */ const char *custom = "mybasename"; char *out = NULL, *err = NULL; size_t out_len = 0, err_len = 0; int code = -1; int rc = run_usage_and_capture(EXIT_SUCCESS, custom, &out, &out_len, &err, &err_len, &code); TEST_ASSERT_EQUAL_INT(0, rc); TEST_ASSERT_EQUAL_INT(0, code); TEST_ASSERT_TRUE(contains_substr(out, custom)); free(out); free(err); } void test_usage_success_writes_nothing_to_stderr(void) { char *out = NULL, *err = NULL; size_t out_len = 0, err_len = 0; int code = -1; int rc = run_usage_and_capture(EXIT_SUCCESS, "basename", &out, &out_len, &err, &err_len, &code); TEST_ASSERT_EQUAL_INT(0, rc); TEST_ASSERT_EQUAL_INT(0, code); TEST_ASSERT_EQUAL_UINT64(0, (unsigned long long)err_len); free(out); free(err); } int main(void) { UNITY_BEGIN(); RUN_TEST(test_usage_success_outputs_usage_and_exits_zero); RUN_TEST(test_usage_success_includes_options_and_examples); RUN_TEST(test_usage_nonzero_status_exits_with_status_and_writes_stderr_only); RUN_TEST(test_usage_respects_program_name_in_output); RUN_TEST(test_usage_success_writes_nothing_to_stderr); return UNITY_END(); }