2 #include "run-command.h"
4 #include "argv-array.h"
6 static inline void close_pair(int fd[2])
13 static inline void dup_devnull(int to)
15 int fd = open("/dev/null", O_RDWR);
21 static char *locate_in_PATH(const char *file)
23 const char *p = getenv("PATH");
24 struct strbuf buf = STRBUF_INIT;
30 const char *end = strchrnul(p, ':');
34 /* POSIX specifies an empty entry as the current directory. */
36 strbuf_add(&buf, p, end - p);
37 strbuf_addch(&buf, '/');
39 strbuf_addstr(&buf, file);
41 if (!access(buf.buf, F_OK))
42 return strbuf_detach(&buf, NULL);
53 static int exists_in_PATH(const char *file)
55 char *r = locate_in_PATH(file);
60 int sane_execvp(const char *file, char * const argv[])
62 if (!execvp(file, argv))
63 return 0; /* cannot happen ;-) */
66 * When a command can't be found because one of the directories
67 * listed in $PATH is unsearchable, execvp reports EACCES, but
68 * careful usability testing (read: analysis of occasional bug
69 * reports) reveals that "No such file or directory" is more
72 * We avoid commands with "/", because execvp will not do $PATH
73 * lookups in that case.
75 * The reassignment of EACCES to errno looks like a no-op below,
76 * but we need to protect against exists_in_PATH overwriting errno.
78 if (errno == EACCES && !strchr(file, '/'))
79 errno = exists_in_PATH(file) ? EACCES : ENOENT;
83 static const char **prepare_shell_cmd(const char **argv)
88 for (argc = 0; argv[argc]; argc++)
90 /* +1 for NULL, +3 for "sh -c" plus extra $0 */
91 nargv = xmalloc(sizeof(*nargv) * (argc + 1 + 3));
94 die("BUG: shell command is empty");
96 if (strcspn(argv[0], "|&;<>()$`\\\"' \t\n*?[#~=%") != strlen(argv[0])) {
97 nargv[nargc++] = "sh";
98 nargv[nargc++] = "-c";
101 nargv[nargc++] = argv[0];
103 struct strbuf arg0 = STRBUF_INIT;
104 strbuf_addf(&arg0, "%s \"$@\"", argv[0]);
105 nargv[nargc++] = strbuf_detach(&arg0, NULL);
109 for (argc = 0; argv[argc]; argc++)
110 nargv[nargc++] = argv[argc];
117 static int execv_shell_cmd(const char **argv)
119 const char **nargv = prepare_shell_cmd(argv);
120 trace_argv_printf(nargv, "trace: exec:");
121 sane_execvp(nargv[0], (char **)nargv);
128 static int child_err = 2;
129 static int child_notifier = -1;
131 static void notify_parent(void)
134 * execvp failed. If possible, we'd like to let start_command
135 * know, so failures like ENOENT can be handled right away; but
136 * otherwise, finish_command will still report the error.
138 xwrite(child_notifier, "", 1);
141 static NORETURN void die_child(const char *err, va_list params)
143 vwritef(child_err, "fatal: ", err, params);
147 static void error_child(const char *err, va_list params)
149 vwritef(child_err, "error: ", err, params);
153 static inline void set_cloexec(int fd)
155 int flags = fcntl(fd, F_GETFD);
157 fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
160 static int wait_or_whine(pid_t pid, const char *argv0, int silent_exec_failure)
162 int status, code = -1;
164 int failed_errno = 0;
166 while ((waiting = waitpid(pid, &status, 0)) < 0 && errno == EINTR)
170 failed_errno = errno;
171 error("waitpid for %s failed: %s", argv0, strerror(errno));
172 } else if (waiting != pid) {
173 error("waitpid is confused (%s)", argv0);
174 } else if (WIFSIGNALED(status)) {
175 code = WTERMSIG(status);
176 error("%s died of signal %d", argv0, code);
178 * This return value is chosen so that code & 0xff
179 * mimics the exit code that a POSIX shell would report for
180 * a program that died from this signal.
183 } else if (WIFEXITED(status)) {
184 code = WEXITSTATUS(status);
186 * Convert special exit code when execvp failed.
190 failed_errno = ENOENT;
193 error("waitpid is confused (%s)", argv0);
195 errno = failed_errno;
199 int start_command(struct child_process *cmd)
201 int need_in, need_out, need_err;
202 int fdin[2], fdout[2], fderr[2];
203 int failed_errno = failed_errno;
206 * In case of errors we must keep the promise to close FDs
207 * that have been passed in via ->in and ->out.
210 need_in = !cmd->no_stdin && cmd->in < 0;
212 if (pipe(fdin) < 0) {
213 failed_errno = errno;
221 need_out = !cmd->no_stdout
222 && !cmd->stdout_to_stderr
225 if (pipe(fdout) < 0) {
226 failed_errno = errno;
236 need_err = !cmd->no_stderr && cmd->err < 0;
238 if (pipe(fderr) < 0) {
239 failed_errno = errno;
249 error("cannot create pipe for %s: %s",
250 cmd->argv[0], strerror(failed_errno));
251 errno = failed_errno;
257 trace_argv_printf(cmd->argv, "trace: run_command:");
263 if (pipe(notify_pipe))
264 notify_pipe[0] = notify_pipe[1] = -1;
269 * Redirect the channel to write syscall error messages to
270 * before redirecting the process's stderr so that all die()
271 * in subsequent call paths use the parent's stderr.
273 if (cmd->no_stderr || need_err) {
275 set_cloexec(child_err);
277 set_die_routine(die_child);
278 set_error_routine(error_child);
280 close(notify_pipe[0]);
281 set_cloexec(notify_pipe[1]);
282 child_notifier = notify_pipe[1];
283 atexit(notify_parent);
290 } else if (cmd->in) {
300 } else if (cmd->err > 1) {
307 else if (cmd->stdout_to_stderr)
312 } else if (cmd->out > 1) {
317 if (cmd->dir && chdir(cmd->dir))
318 die_errno("exec '%s': cd to '%s' failed", cmd->argv[0],
321 for (; *cmd->env; cmd->env++) {
322 if (strchr(*cmd->env, '='))
323 putenv((char *)*cmd->env);
328 if (cmd->preexec_cb) {
330 * We cannot predict what the pre-exec callback does.
331 * Forgo parent notification.
333 close(child_notifier);
339 execv_git_cmd(cmd->argv);
340 } else if (cmd->use_shell) {
341 execv_shell_cmd(cmd->argv);
343 sane_execvp(cmd->argv[0], (char *const*) cmd->argv);
345 if (errno == ENOENT) {
346 if (!cmd->silent_exec_failure)
347 error("cannot run %s: %s", cmd->argv[0],
351 die_errno("cannot exec '%s'", cmd->argv[0]);
355 error("cannot fork() for %s: %s", cmd->argv[0],
356 strerror(failed_errno = errno));
359 * Wait for child's execvp. If the execvp succeeds (or if fork()
360 * failed), EOF is seen immediately by the parent. Otherwise, the
361 * child process sends a single byte.
362 * Note that use of this infrastructure is completely advisory,
363 * therefore, we keep error checks minimal.
365 close(notify_pipe[1]);
366 if (read(notify_pipe[0], ¬ify_pipe[1], 1) == 1) {
368 * At this point we know that fork() succeeded, but execvp()
369 * failed. Errors have been reported to our stderr.
371 wait_or_whine(cmd->pid, cmd->argv[0],
372 cmd->silent_exec_failure);
373 failed_errno = errno;
376 close(notify_pipe[0]);
380 int fhin = 0, fhout = 1, fherr = 2;
381 const char **sargv = cmd->argv;
382 char **env = environ;
385 fhin = open("/dev/null", O_RDWR);
392 fherr = open("/dev/null", O_RDWR);
394 fherr = dup(fderr[1]);
395 else if (cmd->err > 2)
396 fherr = dup(cmd->err);
399 fhout = open("/dev/null", O_RDWR);
400 else if (cmd->stdout_to_stderr)
403 fhout = dup(fdout[1]);
404 else if (cmd->out > 1)
405 fhout = dup(cmd->out);
408 env = make_augmented_environ(cmd->env);
411 cmd->argv = prepare_git_cmd(cmd->argv);
412 } else if (cmd->use_shell) {
413 cmd->argv = prepare_shell_cmd(cmd->argv);
416 cmd->pid = mingw_spawnvpe(cmd->argv[0], cmd->argv, env, cmd->dir,
418 failed_errno = errno;
419 if (cmd->pid < 0 && (!cmd->silent_exec_failure || errno != ENOENT))
420 error("cannot spawn %s: %s", cmd->argv[0], strerror(errno));
450 errno = failed_errno;
472 int finish_command(struct child_process *cmd)
474 return wait_or_whine(cmd->pid, cmd->argv[0], cmd->silent_exec_failure);
477 int run_command(struct child_process *cmd)
479 int code = start_command(cmd);
482 return finish_command(cmd);
485 static void prepare_run_command_v_opt(struct child_process *cmd,
489 memset(cmd, 0, sizeof(*cmd));
491 cmd->no_stdin = opt & RUN_COMMAND_NO_STDIN ? 1 : 0;
492 cmd->git_cmd = opt & RUN_GIT_CMD ? 1 : 0;
493 cmd->stdout_to_stderr = opt & RUN_COMMAND_STDOUT_TO_STDERR ? 1 : 0;
494 cmd->silent_exec_failure = opt & RUN_SILENT_EXEC_FAILURE ? 1 : 0;
495 cmd->use_shell = opt & RUN_USING_SHELL ? 1 : 0;
498 int run_command_v_opt(const char **argv, int opt)
500 struct child_process cmd;
501 prepare_run_command_v_opt(&cmd, argv, opt);
502 return run_command(&cmd);
505 int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env)
507 struct child_process cmd;
508 prepare_run_command_v_opt(&cmd, argv, opt);
511 return run_command(&cmd);
515 static pthread_t main_thread;
516 static int main_thread_set;
517 static pthread_key_t async_key;
519 static void *run_thread(void *data)
521 struct async *async = data;
524 pthread_setspecific(async_key, async);
525 ret = async->proc(async->proc_in, async->proc_out, async->data);
529 static NORETURN void die_async(const char *err, va_list params)
531 vreportf("fatal: ", err, params);
533 if (!pthread_equal(main_thread, pthread_self())) {
534 struct async *async = pthread_getspecific(async_key);
535 if (async->proc_in >= 0)
536 close(async->proc_in);
537 if (async->proc_out >= 0)
538 close(async->proc_out);
539 pthread_exit((void *)128);
546 int start_async(struct async *async)
548 int need_in, need_out;
549 int fdin[2], fdout[2];
550 int proc_in, proc_out;
552 need_in = async->in < 0;
554 if (pipe(fdin) < 0) {
557 return error("cannot create pipe: %s", strerror(errno));
562 need_out = async->out < 0;
564 if (pipe(fdout) < 0) {
569 return error("cannot create pipe: %s", strerror(errno));
571 async->out = fdout[0];
584 proc_out = async->out;
589 /* Flush stdio before fork() to avoid cloning buffers */
593 if (async->pid < 0) {
594 error("fork (async) failed: %s", strerror(errno));
602 exit(!!async->proc(proc_in, proc_out, async->data));
615 if (!main_thread_set) {
617 * We assume that the first time that start_async is called
618 * it is from the main thread.
621 main_thread = pthread_self();
622 pthread_key_create(&async_key, NULL);
623 set_die_routine(die_async);
627 set_cloexec(proc_in);
629 set_cloexec(proc_out);
630 async->proc_in = proc_in;
631 async->proc_out = proc_out;
633 int err = pthread_create(&async->tid, NULL, run_thread, async);
635 error("cannot create thread: %s", strerror(err));
655 int finish_async(struct async *async)
658 return wait_or_whine(async->pid, "child process", 0);
660 void *ret = (void *)(intptr_t)(-1);
662 if (pthread_join(async->tid, &ret))
663 error("pthread_join failed");
664 return (int)(intptr_t)ret;
668 int run_hook(const char *index_file, const char *name, ...)
670 struct child_process hook;
671 struct argv_array argv = ARGV_ARRAY_INIT;
672 const char *p, *env[2];
673 char index[PATH_MAX];
677 if (access(git_path("hooks/%s", name), X_OK) < 0)
680 va_start(args, name);
681 argv_array_push(&argv, git_path("hooks/%s", name));
682 while ((p = va_arg(args, const char *)))
683 argv_array_push(&argv, p);
686 memset(&hook, 0, sizeof(hook));
687 hook.argv = argv.argv;
689 hook.stdout_to_stderr = 1;
691 snprintf(index, sizeof(index), "GIT_INDEX_FILE=%s", index_file);
697 ret = run_command(&hook);
698 argv_array_clear(&argv);