Merge branch 'maint'
[git.git] / run-command.c
blob2feb493951322617692085998ac8507cdba9dd30
1 #include "cache.h"
2 #include "run-command.h"
3 #include "exec_cmd.h"
5 static inline void close_pair(int fd[2])
7 close(fd[0]);
8 close(fd[1]);
11 #ifndef WIN32
12 static inline void dup_devnull(int to)
14 int fd = open("/dev/null", O_RDWR);
15 dup2(fd, to);
16 close(fd);
18 #endif
20 static const char **prepare_shell_cmd(const char **argv)
22 int argc, nargc = 0;
23 const char **nargv;
25 for (argc = 0; argv[argc]; argc++)
26 ; /* just counting */
27 /* +1 for NULL, +3 for "sh -c" plus extra $0 */
28 nargv = xmalloc(sizeof(*nargv) * (argc + 1 + 3));
30 if (argc < 1)
31 die("BUG: shell command is empty");
33 if (strcspn(argv[0], "|&;<>()$`\\\"' \t\n*?[#~=%") != strlen(argv[0])) {
34 nargv[nargc++] = "sh";
35 nargv[nargc++] = "-c";
37 if (argc < 2)
38 nargv[nargc++] = argv[0];
39 else {
40 struct strbuf arg0 = STRBUF_INIT;
41 strbuf_addf(&arg0, "%s \"$@\"", argv[0]);
42 nargv[nargc++] = strbuf_detach(&arg0, NULL);
46 for (argc = 0; argv[argc]; argc++)
47 nargv[nargc++] = argv[argc];
48 nargv[nargc] = NULL;
50 return nargv;
53 #ifndef WIN32
54 static int execv_shell_cmd(const char **argv)
56 const char **nargv = prepare_shell_cmd(argv);
57 trace_argv_printf(nargv, "trace: exec:");
58 execvp(nargv[0], (char **)nargv);
59 free(nargv);
60 return -1;
62 #endif
64 #ifndef WIN32
65 static int child_err = 2;
66 static int child_notifier = -1;
68 static void notify_parent(void)
70 write(child_notifier, "", 1);
73 static NORETURN void die_child(const char *err, va_list params)
75 char msg[4096];
76 int len = vsnprintf(msg, sizeof(msg), err, params);
77 if (len > sizeof(msg))
78 len = sizeof(msg);
80 write(child_err, "fatal: ", 7);
81 write(child_err, msg, len);
82 write(child_err, "\n", 1);
83 exit(128);
86 static inline void set_cloexec(int fd)
88 int flags = fcntl(fd, F_GETFD);
89 if (flags >= 0)
90 fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
92 #endif
94 static int wait_or_whine(pid_t pid, const char *argv0, int silent_exec_failure)
96 int status, code = -1;
97 pid_t waiting;
98 int failed_errno = 0;
100 while ((waiting = waitpid(pid, &status, 0)) < 0 && errno == EINTR)
101 ; /* nothing */
103 if (waiting < 0) {
104 failed_errno = errno;
105 error("waitpid for %s failed: %s", argv0, strerror(errno));
106 } else if (waiting != pid) {
107 error("waitpid is confused (%s)", argv0);
108 } else if (WIFSIGNALED(status)) {
109 code = WTERMSIG(status);
110 error("%s died of signal %d", argv0, code);
112 * This return value is chosen so that code & 0xff
113 * mimics the exit code that a POSIX shell would report for
114 * a program that died from this signal.
116 code -= 128;
117 } else if (WIFEXITED(status)) {
118 code = WEXITSTATUS(status);
120 * Convert special exit code when execvp failed.
122 if (code == 127) {
123 code = -1;
124 failed_errno = ENOENT;
125 if (!silent_exec_failure)
126 error("cannot run %s: %s", argv0,
127 strerror(ENOENT));
129 } else {
130 error("waitpid is confused (%s)", argv0);
132 errno = failed_errno;
133 return code;
136 int start_command(struct child_process *cmd)
138 int need_in, need_out, need_err;
139 int fdin[2], fdout[2], fderr[2];
140 int failed_errno = failed_errno;
143 * In case of errors we must keep the promise to close FDs
144 * that have been passed in via ->in and ->out.
147 need_in = !cmd->no_stdin && cmd->in < 0;
148 if (need_in) {
149 if (pipe(fdin) < 0) {
150 failed_errno = errno;
151 if (cmd->out > 0)
152 close(cmd->out);
153 goto fail_pipe;
155 cmd->in = fdin[1];
158 need_out = !cmd->no_stdout
159 && !cmd->stdout_to_stderr
160 && cmd->out < 0;
161 if (need_out) {
162 if (pipe(fdout) < 0) {
163 failed_errno = errno;
164 if (need_in)
165 close_pair(fdin);
166 else if (cmd->in)
167 close(cmd->in);
168 goto fail_pipe;
170 cmd->out = fdout[0];
173 need_err = !cmd->no_stderr && cmd->err < 0;
174 if (need_err) {
175 if (pipe(fderr) < 0) {
176 failed_errno = errno;
177 if (need_in)
178 close_pair(fdin);
179 else if (cmd->in)
180 close(cmd->in);
181 if (need_out)
182 close_pair(fdout);
183 else if (cmd->out)
184 close(cmd->out);
185 fail_pipe:
186 error("cannot create pipe for %s: %s",
187 cmd->argv[0], strerror(failed_errno));
188 errno = failed_errno;
189 return -1;
191 cmd->err = fderr[0];
194 trace_argv_printf(cmd->argv, "trace: run_command:");
196 #ifndef WIN32
198 int notify_pipe[2];
199 if (pipe(notify_pipe))
200 notify_pipe[0] = notify_pipe[1] = -1;
202 fflush(NULL);
203 cmd->pid = fork();
204 if (!cmd->pid) {
206 * Redirect the channel to write syscall error messages to
207 * before redirecting the process's stderr so that all die()
208 * in subsequent call paths use the parent's stderr.
210 if (cmd->no_stderr || need_err) {
211 child_err = dup(2);
212 set_cloexec(child_err);
214 set_die_routine(die_child);
216 close(notify_pipe[0]);
217 set_cloexec(notify_pipe[1]);
218 child_notifier = notify_pipe[1];
219 atexit(notify_parent);
221 if (cmd->no_stdin)
222 dup_devnull(0);
223 else if (need_in) {
224 dup2(fdin[0], 0);
225 close_pair(fdin);
226 } else if (cmd->in) {
227 dup2(cmd->in, 0);
228 close(cmd->in);
231 if (cmd->no_stderr)
232 dup_devnull(2);
233 else if (need_err) {
234 dup2(fderr[1], 2);
235 close_pair(fderr);
238 if (cmd->no_stdout)
239 dup_devnull(1);
240 else if (cmd->stdout_to_stderr)
241 dup2(2, 1);
242 else if (need_out) {
243 dup2(fdout[1], 1);
244 close_pair(fdout);
245 } else if (cmd->out > 1) {
246 dup2(cmd->out, 1);
247 close(cmd->out);
250 if (cmd->dir && chdir(cmd->dir))
251 die_errno("exec '%s': cd to '%s' failed", cmd->argv[0],
252 cmd->dir);
253 if (cmd->env) {
254 for (; *cmd->env; cmd->env++) {
255 if (strchr(*cmd->env, '='))
256 putenv((char *)*cmd->env);
257 else
258 unsetenv(*cmd->env);
261 if (cmd->preexec_cb) {
263 * We cannot predict what the pre-exec callback does.
264 * Forgo parent notification.
266 close(child_notifier);
267 child_notifier = -1;
269 cmd->preexec_cb();
271 if (cmd->git_cmd) {
272 execv_git_cmd(cmd->argv);
273 } else if (cmd->use_shell) {
274 execv_shell_cmd(cmd->argv);
275 } else {
276 execvp(cmd->argv[0], (char *const*) cmd->argv);
279 * Do not check for cmd->silent_exec_failure; the parent
280 * process will check it when it sees this exit code.
282 if (errno == ENOENT)
283 exit(127);
284 else
285 die_errno("cannot exec '%s'", cmd->argv[0]);
287 if (cmd->pid < 0)
288 error("cannot fork() for %s: %s", cmd->argv[0],
289 strerror(failed_errno = errno));
292 * Wait for child's execvp. If the execvp succeeds (or if fork()
293 * failed), EOF is seen immediately by the parent. Otherwise, the
294 * child process sends a single byte.
295 * Note that use of this infrastructure is completely advisory,
296 * therefore, we keep error checks minimal.
298 close(notify_pipe[1]);
299 if (read(notify_pipe[0], &notify_pipe[1], 1) == 1) {
301 * At this point we know that fork() succeeded, but execvp()
302 * failed. Errors have been reported to our stderr.
304 wait_or_whine(cmd->pid, cmd->argv[0],
305 cmd->silent_exec_failure);
306 failed_errno = errno;
307 cmd->pid = -1;
309 close(notify_pipe[0]);
311 #else
313 int fhin = 0, fhout = 1, fherr = 2;
314 const char **sargv = cmd->argv;
315 char **env = environ;
317 if (cmd->no_stdin)
318 fhin = open("/dev/null", O_RDWR);
319 else if (need_in)
320 fhin = dup(fdin[0]);
321 else if (cmd->in)
322 fhin = dup(cmd->in);
324 if (cmd->no_stderr)
325 fherr = open("/dev/null", O_RDWR);
326 else if (need_err)
327 fherr = dup(fderr[1]);
329 if (cmd->no_stdout)
330 fhout = open("/dev/null", O_RDWR);
331 else if (cmd->stdout_to_stderr)
332 fhout = dup(fherr);
333 else if (need_out)
334 fhout = dup(fdout[1]);
335 else if (cmd->out > 1)
336 fhout = dup(cmd->out);
338 if (cmd->dir)
339 die("chdir in start_command() not implemented");
340 if (cmd->env)
341 env = make_augmented_environ(cmd->env);
343 if (cmd->git_cmd) {
344 cmd->argv = prepare_git_cmd(cmd->argv);
345 } else if (cmd->use_shell) {
346 cmd->argv = prepare_shell_cmd(cmd->argv);
349 cmd->pid = mingw_spawnvpe(cmd->argv[0], cmd->argv, env,
350 fhin, fhout, fherr);
351 failed_errno = errno;
352 if (cmd->pid < 0 && (!cmd->silent_exec_failure || errno != ENOENT))
353 error("cannot spawn %s: %s", cmd->argv[0], strerror(errno));
355 if (cmd->env)
356 free_environ(env);
357 if (cmd->git_cmd)
358 free(cmd->argv);
360 cmd->argv = sargv;
361 if (fhin != 0)
362 close(fhin);
363 if (fhout != 1)
364 close(fhout);
365 if (fherr != 2)
366 close(fherr);
368 #endif
370 if (cmd->pid < 0) {
371 if (need_in)
372 close_pair(fdin);
373 else if (cmd->in)
374 close(cmd->in);
375 if (need_out)
376 close_pair(fdout);
377 else if (cmd->out)
378 close(cmd->out);
379 if (need_err)
380 close_pair(fderr);
381 errno = failed_errno;
382 return -1;
385 if (need_in)
386 close(fdin[0]);
387 else if (cmd->in)
388 close(cmd->in);
390 if (need_out)
391 close(fdout[1]);
392 else if (cmd->out)
393 close(cmd->out);
395 if (need_err)
396 close(fderr[1]);
398 return 0;
401 int finish_command(struct child_process *cmd)
403 return wait_or_whine(cmd->pid, cmd->argv[0], cmd->silent_exec_failure);
406 int run_command(struct child_process *cmd)
408 int code = start_command(cmd);
409 if (code)
410 return code;
411 return finish_command(cmd);
414 static void prepare_run_command_v_opt(struct child_process *cmd,
415 const char **argv,
416 int opt)
418 memset(cmd, 0, sizeof(*cmd));
419 cmd->argv = argv;
420 cmd->no_stdin = opt & RUN_COMMAND_NO_STDIN ? 1 : 0;
421 cmd->git_cmd = opt & RUN_GIT_CMD ? 1 : 0;
422 cmd->stdout_to_stderr = opt & RUN_COMMAND_STDOUT_TO_STDERR ? 1 : 0;
423 cmd->silent_exec_failure = opt & RUN_SILENT_EXEC_FAILURE ? 1 : 0;
424 cmd->use_shell = opt & RUN_USING_SHELL ? 1 : 0;
427 int run_command_v_opt(const char **argv, int opt)
429 struct child_process cmd;
430 prepare_run_command_v_opt(&cmd, argv, opt);
431 return run_command(&cmd);
434 int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env)
436 struct child_process cmd;
437 prepare_run_command_v_opt(&cmd, argv, opt);
438 cmd.dir = dir;
439 cmd.env = env;
440 return run_command(&cmd);
443 #ifdef WIN32
444 static unsigned __stdcall run_thread(void *data)
446 struct async *async = data;
447 return async->proc(async->fd_for_proc, async->data);
449 #endif
451 int start_async(struct async *async)
453 int pipe_out[2];
455 if (pipe(pipe_out) < 0)
456 return error("cannot create pipe: %s", strerror(errno));
457 async->out = pipe_out[0];
459 #ifndef WIN32
460 /* Flush stdio before fork() to avoid cloning buffers */
461 fflush(NULL);
463 async->pid = fork();
464 if (async->pid < 0) {
465 error("fork (async) failed: %s", strerror(errno));
466 close_pair(pipe_out);
467 return -1;
469 if (!async->pid) {
470 close(pipe_out[0]);
471 exit(!!async->proc(pipe_out[1], async->data));
473 close(pipe_out[1]);
474 #else
475 async->fd_for_proc = pipe_out[1];
476 async->tid = (HANDLE) _beginthreadex(NULL, 0, run_thread, async, 0, NULL);
477 if (!async->tid) {
478 error("cannot create thread: %s", strerror(errno));
479 close_pair(pipe_out);
480 return -1;
482 #endif
483 return 0;
486 int finish_async(struct async *async)
488 #ifndef WIN32
489 int ret = wait_or_whine(async->pid, "child process", 0);
490 #else
491 DWORD ret = 0;
492 if (WaitForSingleObject(async->tid, INFINITE) != WAIT_OBJECT_0)
493 ret = error("waiting for thread failed: %lu", GetLastError());
494 else if (!GetExitCodeThread(async->tid, &ret))
495 ret = error("cannot get thread exit code: %lu", GetLastError());
496 CloseHandle(async->tid);
497 #endif
498 return ret;
501 int run_hook(const char *index_file, const char *name, ...)
503 struct child_process hook;
504 const char **argv = NULL, *env[2];
505 char index[PATH_MAX];
506 va_list args;
507 int ret;
508 size_t i = 0, alloc = 0;
510 if (access(git_path("hooks/%s", name), X_OK) < 0)
511 return 0;
513 va_start(args, name);
514 ALLOC_GROW(argv, i + 1, alloc);
515 argv[i++] = git_path("hooks/%s", name);
516 while (argv[i-1]) {
517 ALLOC_GROW(argv, i + 1, alloc);
518 argv[i++] = va_arg(args, const char *);
520 va_end(args);
522 memset(&hook, 0, sizeof(hook));
523 hook.argv = argv;
524 hook.no_stdin = 1;
525 hook.stdout_to_stderr = 1;
526 if (index_file) {
527 snprintf(index, sizeof(index), "GIT_INDEX_FILE=%s", index_file);
528 env[0] = index;
529 env[1] = NULL;
530 hook.env = env;
533 ret = run_command(&hook);
534 free(argv);
535 return ret;