[thirdparty/git.git] / run-command.c

#include "cache.h"
#include "run-command.h"
#include "exec_cmd.h"

static inline void close_pair(int fd[2])
{
	close(fd[0]);
	close(fd[1]);
}

static inline void dup_devnull(int to)
{
	int fd = open("/dev/null", O_RDWR);
	dup2(fd, to);
	close(fd);
}

int start_command(struct child_process *cmd)
{
	int need_in, need_out, need_err;
	int fdin[2], fdout[2], fderr[2];
	int failed_errno = failed_errno;

	/*
	 * In case of errors we must keep the promise to close FDs
	 * that have been passed in via ->in and ->out.
	 */

	need_in = !cmd->no_stdin && cmd->in < 0;
	if (need_in) {
		if (pipe(fdin) < 0) {
			failed_errno = errno;
			if (cmd->out > 0)
				close(cmd->out);
			goto fail_pipe;
		}
		cmd->in = fdin[1];
	}

	need_out = !cmd->no_stdout
		&& !cmd->stdout_to_stderr
		&& cmd->out < 0;
	if (need_out) {
		if (pipe(fdout) < 0) {
			failed_errno = errno;
			if (need_in)
				close_pair(fdin);
			else if (cmd->in)
				close(cmd->in);
			goto fail_pipe;
		}
		cmd->out = fdout[0];
	}

	need_err = !cmd->no_stderr && cmd->err < 0;
	if (need_err) {
		if (pipe(fderr) < 0) {
			failed_errno = errno;
			if (need_in)
				close_pair(fdin);
			else if (cmd->in)
				close(cmd->in);
			if (need_out)
				close_pair(fdout);
			else if (cmd->out)
				close(cmd->out);
fail_pipe:
			error("cannot create pipe for %s: %s",
				cmd->argv[0], strerror(failed_errno));
			errno = failed_errno;
			return -1;
		}
		cmd->err = fderr[0];
	}

	trace_argv_printf(cmd->argv, "trace: run_command:");

#ifndef __MINGW32__
	fflush(NULL);
	cmd->pid = fork();
	if (!cmd->pid) {
		if (cmd->no_stdin)
			dup_devnull(0);
		else if (need_in) {
			dup2(fdin[0], 0);
			close_pair(fdin);
		} else if (cmd->in) {
			dup2(cmd->in, 0);
			close(cmd->in);
		}

		if (cmd->no_stderr)
			dup_devnull(2);
		else if (need_err) {
			dup2(fderr[1], 2);
			close_pair(fderr);
		}

		if (cmd->no_stdout)
			dup_devnull(1);
		else if (cmd->stdout_to_stderr)
			dup2(2, 1);
		else if (need_out) {
			dup2(fdout[1], 1);
			close_pair(fdout);
		} else if (cmd->out > 1) {
			dup2(cmd->out, 1);
			close(cmd->out);
		}

		if (cmd->dir && chdir(cmd->dir))
			die_errno("exec '%s': cd to '%s' failed", cmd->argv[0],
			    cmd->dir);
		if (cmd->env) {
			for (; *cmd->env; cmd->env++) {
				if (strchr(*cmd->env, '='))
					putenv((char *)*cmd->env);
				else
					unsetenv(*cmd->env);
			}
		}
		if (cmd->preexec_cb)
			cmd->preexec_cb();
		if (cmd->git_cmd) {
			execv_git_cmd(cmd->argv);
		} else {
			execvp(cmd->argv[0], (char *const*) cmd->argv);
		}
		trace_printf("trace: exec '%s' failed: %s\n", cmd->argv[0],
				strerror(errno));
		exit(127);
	}
	if (cmd->pid < 0)
		error("cannot fork() for %s: %s", cmd->argv[0],
			strerror(failed_errno = errno));
#else
	int s0 = -1, s1 = -1, s2 = -1;	/* backups of stdin, stdout, stderr */
	const char **sargv = cmd->argv;
	char **env = environ;

	if (cmd->no_stdin) {
		s0 = dup(0);
		dup_devnull(0);
	} else if (need_in) {
		s0 = dup(0);
		dup2(fdin[0], 0);
	} else if (cmd->in) {
		s0 = dup(0);
		dup2(cmd->in, 0);
	}

	if (cmd->no_stderr) {
		s2 = dup(2);
		dup_devnull(2);
	} else if (need_err) {
		s2 = dup(2);
		dup2(fderr[1], 2);
	}

	if (cmd->no_stdout) {
		s1 = dup(1);
		dup_devnull(1);
	} else if (cmd->stdout_to_stderr) {
		s1 = dup(1);
		dup2(2, 1);
	} else if (need_out) {
		s1 = dup(1);
		dup2(fdout[1], 1);
	} else if (cmd->out > 1) {
		s1 = dup(1);
		dup2(cmd->out, 1);
	}

	if (cmd->dir)
		die("chdir in start_command() not implemented");
	if (cmd->env) {
		env = copy_environ();
		for (; *cmd->env; cmd->env++)
			env = env_setenv(env, *cmd->env);
	}

	if (cmd->git_cmd) {
		cmd->argv = prepare_git_cmd(cmd->argv);
	}

	cmd->pid = mingw_spawnvpe(cmd->argv[0], cmd->argv, env);
	failed_errno = errno;
	if (cmd->pid < 0 && (!cmd->silent_exec_failure || errno != ENOENT))
		error("cannot spawn %s: %s", cmd->argv[0], strerror(errno));

	if (cmd->env)
		free_environ(env);
	if (cmd->git_cmd)
		free(cmd->argv);

	cmd->argv = sargv;
	if (s0 >= 0)
		dup2(s0, 0), close(s0);
	if (s1 >= 0)
		dup2(s1, 1), close(s1);
	if (s2 >= 0)
		dup2(s2, 2), close(s2);
#endif

	if (cmd->pid < 0) {
		if (need_in)
			close_pair(fdin);
		else if (cmd->in)
			close(cmd->in);
		if (need_out)
			close_pair(fdout);
		else if (cmd->out)
			close(cmd->out);
		if (need_err)
			close_pair(fderr);
		errno = failed_errno;
		return -1;
	}

	if (need_in)
		close(fdin[0]);
	else if (cmd->in)
		close(cmd->in);

	if (need_out)
		close(fdout[1]);
	else if (cmd->out)
		close(cmd->out);

	if (need_err)
		close(fderr[1]);

	return 0;
}

static int wait_or_whine(pid_t pid, const char *argv0, int silent_exec_failure)
{
	int status, code = -1;
	pid_t waiting;
	int failed_errno = 0;

	while ((waiting = waitpid(pid, &status, 0)) < 0 && errno == EINTR)
		;	/* nothing */

	if (waiting < 0) {
		failed_errno = errno;
		error("waitpid for %s failed: %s", argv0, strerror(errno));
	} else if (waiting != pid) {
		error("waitpid is confused (%s)", argv0);
	} else if (WIFSIGNALED(status)) {
		code = WTERMSIG(status);
		error("%s died of signal %d", argv0, code);
		/*
		 * This return value is chosen so that code & 0xff
		 * mimics the exit code that a POSIX shell would report for
		 * a program that died from this signal.
		 */
		code -= 128;
	} else if (WIFEXITED(status)) {
		code = WEXITSTATUS(status);
		/*
		 * Convert special exit code when execvp failed.
		 */
		if (code == 127) {
			code = -1;
			failed_errno = ENOENT;
			if (!silent_exec_failure)
				error("cannot run %s: %s", argv0,
					strerror(ENOENT));
		}
	} else {
		error("waitpid is confused (%s)", argv0);
	}
	errno = failed_errno;
	return code;
}

int finish_command(struct child_process *cmd)
{
	return wait_or_whine(cmd->pid, cmd->argv[0], cmd->silent_exec_failure);
}

int run_command(struct child_process *cmd)
{
	int code = start_command(cmd);
	if (code)
		return code;
	return finish_command(cmd);
}

static void prepare_run_command_v_opt(struct child_process *cmd,
				      const char **argv,
				      int opt)
{
	memset(cmd, 0, sizeof(*cmd));
	cmd->argv = argv;
	cmd->no_stdin = opt & RUN_COMMAND_NO_STDIN ? 1 : 0;
	cmd->git_cmd = opt & RUN_GIT_CMD ? 1 : 0;
	cmd->stdout_to_stderr = opt & RUN_COMMAND_STDOUT_TO_STDERR ? 1 : 0;
	cmd->silent_exec_failure = opt & RUN_SILENT_EXEC_FAILURE ? 1 : 0;
}

int run_command_v_opt(const char **argv, int opt)
{
	struct child_process cmd;
	prepare_run_command_v_opt(&cmd, argv, opt);
	return run_command(&cmd);
}

int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env)
{
	struct child_process cmd;
	prepare_run_command_v_opt(&cmd, argv, opt);
	cmd.dir = dir;
	cmd.env = env;
	return run_command(&cmd);
}

#ifdef __MINGW32__
static __stdcall unsigned run_thread(void *data)
{
	struct async *async = data;
	return async->proc(async->fd_for_proc, async->data);
}
#endif

int start_async(struct async *async)
{
	int pipe_out[2];

	if (pipe(pipe_out) < 0)
		return error("cannot create pipe: %s", strerror(errno));
	async->out = pipe_out[0];

#ifndef __MINGW32__
	/* Flush stdio before fork() to avoid cloning buffers */
	fflush(NULL);

	async->pid = fork();
	if (async->pid < 0) {
		error("fork (async) failed: %s", strerror(errno));
		close_pair(pipe_out);
		return -1;
	}
	if (!async->pid) {
		close(pipe_out[0]);
		exit(!!async->proc(pipe_out[1], async->data));
	}
	close(pipe_out[1]);
#else
	async->fd_for_proc = pipe_out[1];
	async->tid = (HANDLE) _beginthreadex(NULL, 0, run_thread, async, 0, NULL);
	if (!async->tid) {
		error("cannot create thread: %s", strerror(errno));
		close_pair(pipe_out);
		return -1;
	}
#endif
	return 0;
}

int finish_async(struct async *async)
{
#ifndef __MINGW32__
	int ret = wait_or_whine(async->pid, "child process", 0);
#else
	DWORD ret = 0;
	if (WaitForSingleObject(async->tid, INFINITE) != WAIT_OBJECT_0)
		ret = error("waiting for thread failed: %lu", GetLastError());
	else if (!GetExitCodeThread(async->tid, &ret))
		ret = error("cannot get thread exit code: %lu", GetLastError());
	CloseHandle(async->tid);
#endif
	return ret;
}

int run_hook(const char *index_file, const char *name, ...)
{
	struct child_process hook;
	const char **argv = NULL, *env[2];
	char index[PATH_MAX];
	va_list args;
	int ret;
	size_t i = 0, alloc = 0;

	if (access(git_path("hooks/%s", name), X_OK) < 0)
		return 0;

	va_start(args, name);
	ALLOC_GROW(argv, i + 1, alloc);
	argv[i++] = git_path("hooks/%s", name);
	while (argv[i-1]) {
		ALLOC_GROW(argv, i + 1, alloc);
		argv[i++] = va_arg(args, const char *);
	}
	va_end(args);

	memset(&hook, 0, sizeof(hook));
	hook.argv = argv;
	hook.no_stdin = 1;
	hook.stdout_to_stderr = 1;
	if (index_file) {
		snprintf(index, sizeof(index), "GIT_INDEX_FILE=%s", index_file);
		env[0] = index;
		env[1] = NULL;
		hook.env = env;
	}

	ret = run_command(&hook);
	free(argv);
	return ret;
}
Commit	Line	Data
b1bf95bb JW	1	#include "cache.h"
b1bf95bb JW	2	#include "run-command.h"
77cb17e9	3	#include "exec_cmd.h"
b1bf95bb	4
9dc09c76 SP	5	static inline void close_pair(int fd[2])
	6	{
	7	close(fd[0]);
	8	close(fd[1]);
	9	}
	10
e4507ae8 SP	11	static inline void dup_devnull(int to)
	12	{
	13	int fd = open("/dev/null", O_RDWR);
	14	dup2(fd, to);
	15	close(fd);
	16	}
	17
ebcb5d16	18	int start_command(struct child_process *cmd)
b1bf95bb	19	{
f3b33f1d JS	20	int need_in, need_out, need_err;
f3b33f1d JS	21	int fdin[2], fdout[2], fderr[2];
5a7a3671	22	int failed_errno = failed_errno;
4919bf03	23
c20181e3 JS	24	/*
	25	* In case of errors we must keep the promise to close FDs
	26	* that have been passed in via ->in and ->out.
	27	*/
	28
e4507ae8	29	need_in = !cmd->no_stdin && cmd->in < 0;
4919bf03	30	if (need_in) {
c20181e3	31	if (pipe(fdin) < 0) {
0ac77ec3	32	failed_errno = errno;
c20181e3 JS	33	if (cmd->out > 0)
c20181e3 JS	34	close(cmd->out);
0ac77ec3	35	goto fail_pipe;
c20181e3	36	}
4919bf03	37	cmd->in = fdin[1];
4919bf03 SP	38	}
4919bf03 SP	39
e4507ae8 SP	40	need_out = !cmd->no_stdout
	41	&& !cmd->stdout_to_stderr
	42	&& cmd->out < 0;
f4bba25b SP	43	if (need_out) {
f4bba25b SP	44	if (pipe(fdout) < 0) {
0ac77ec3	45	failed_errno = errno;
f4bba25b SP	46	if (need_in)
f4bba25b SP	47	close_pair(fdin);
c20181e3 JS	48	else if (cmd->in)
c20181e3 JS	49	close(cmd->in);
0ac77ec3	50	goto fail_pipe;
f4bba25b SP	51	}
f4bba25b SP	52	cmd->out = fdout[0];
f4bba25b SP	53	}
f4bba25b SP	54
b73a4397	55	need_err = !cmd->no_stderr && cmd->err < 0;
f3b33f1d JS	56	if (need_err) {
f3b33f1d JS	57	if (pipe(fderr) < 0) {
0ac77ec3	58	failed_errno = errno;
f3b33f1d JS	59	if (need_in)
f3b33f1d JS	60	close_pair(fdin);
c20181e3 JS	61	else if (cmd->in)
c20181e3 JS	62	close(cmd->in);
f3b33f1d JS	63	if (need_out)
f3b33f1d JS	64	close_pair(fdout);
c20181e3 JS	65	else if (cmd->out)
c20181e3 JS	66	close(cmd->out);
0ac77ec3 JS	67	fail_pipe:
	68	error("cannot create pipe for %s: %s",
	69	cmd->argv[0], strerror(failed_errno));
	70	errno = failed_errno;
	71	return -1;
f3b33f1d JS	72	}
	73	cmd->err = fderr[0];
	74	}
	75
8852f5d7 JS	76	trace_argv_printf(cmd->argv, "trace: run_command:");
8852f5d7 JS	77
ba26f296	78	#ifndef __MINGW32__
7d0b18a4	79	fflush(NULL);
ebcb5d16	80	cmd->pid = fork();
ebcb5d16	81	if (!cmd->pid) {
e4507ae8 SP	82	if (cmd->no_stdin)
	83	dup_devnull(0);
	84	else if (need_in) {
4919bf03	85	dup2(fdin[0], 0);
9dc09c76	86	close_pair(fdin);
4919bf03 SP	87	} else if (cmd->in) {
	88	dup2(cmd->in, 0);
	89	close(cmd->in);
95d3c4f5	90	}
4919bf03	91
ce2cf27a CC	92	if (cmd->no_stderr)
	93	dup_devnull(2);
	94	else if (need_err) {
	95	dup2(fderr[1], 2);
	96	close_pair(fderr);
	97	}
	98
e4507ae8 SP	99	if (cmd->no_stdout)
	100	dup_devnull(1);
	101	else if (cmd->stdout_to_stderr)
cd83c74c	102	dup2(2, 1);
f4bba25b SP	103	else if (need_out) {
	104	dup2(fdout[1], 1);
	105	close_pair(fdout);
	106	} else if (cmd->out > 1) {
	107	dup2(cmd->out, 1);
	108	close(cmd->out);
	109	}
	110
1568fea0	111	if (cmd->dir && chdir(cmd->dir))
d824cbba TR	112	die_errno("exec '%s': cd to '%s' failed", cmd->argv[0],
d824cbba TR	113	cmd->dir);
ee493148	114	if (cmd->env) {
3427b375 AR	115	for (; *cmd->env; cmd->env++) {
3427b375 AR	116	if (strchr(*cmd->env, '='))
4b25d091	117	putenv((char )cmd->env);
3427b375 AR	118	else
	119	unsetenv(*cmd->env);
	120	}
ee493148	121	}
ccf08bc3 JK	122	if (cmd->preexec_cb)
ccf08bc3 JK	123	cmd->preexec_cb();
f1000898 SP	124	if (cmd->git_cmd) {
f1000898 SP	125	execv_git_cmd(cmd->argv);
77cb17e9	126	} else {
f1000898	127	execvp(cmd->argv[0], (char const) cmd->argv);
128aed68	128	}
45c0961c JK	129	trace_printf("trace: exec '%s' failed: %s\n", cmd->argv[0],
	130	strerror(errno));
	131	exit(127);
b1bf95bb	132	}
0ac77ec3 JS	133	if (cmd->pid < 0)
	134	error("cannot fork() for %s: %s", cmd->argv[0],
	135	strerror(failed_errno = errno));
ba26f296 JS	136	#else
ba26f296 JS	137	int s0 = -1, s1 = -1, s2 = -1; /* backups of stdin, stdout, stderr */
108ac313	138	const char **sargv = cmd->argv;
ba26f296	139	char **env = environ;
ba26f296 JS	140
	141	if (cmd->no_stdin) {
	142	s0 = dup(0);
	143	dup_devnull(0);
	144	} else if (need_in) {
	145	s0 = dup(0);
	146	dup2(fdin[0], 0);
	147	} else if (cmd->in) {
	148	s0 = dup(0);
	149	dup2(cmd->in, 0);
	150	}
	151
	152	if (cmd->no_stderr) {
	153	s2 = dup(2);
	154	dup_devnull(2);
	155	} else if (need_err) {
	156	s2 = dup(2);
	157	dup2(fderr[1], 2);
	158	}
	159
	160	if (cmd->no_stdout) {
	161	s1 = dup(1);
	162	dup_devnull(1);
	163	} else if (cmd->stdout_to_stderr) {
	164	s1 = dup(1);
	165	dup2(2, 1);
	166	} else if (need_out) {
	167	s1 = dup(1);
	168	dup2(fdout[1], 1);
	169	} else if (cmd->out > 1) {
	170	s1 = dup(1);
	171	dup2(cmd->out, 1);
	172	}
	173
	174	if (cmd->dir)
	175	die("chdir in start_command() not implemented");
	176	if (cmd->env) {
	177	env = copy_environ();
	178	for (; *cmd->env; cmd->env++)
	179	env = env_setenv(env, *cmd->env);
	180	}
	181
	182	if (cmd->git_cmd) {
108ac313	183	cmd->argv = prepare_git_cmd(cmd->argv);
ba26f296 JS	184	}
ba26f296 JS	185
7e5d7768	186	cmd->pid = mingw_spawnvpe(cmd->argv[0], cmd->argv, env);
0ac77ec3	187	failed_errno = errno;
c024beb5	188	if (cmd->pid < 0 && (!cmd->silent_exec_failure \|\| errno != ENOENT))
0ac77ec3	189	error("cannot spawn %s: %s", cmd->argv[0], strerror(errno));
ba26f296 JS	190
	191	if (cmd->env)
	192	free_environ(env);
	193	if (cmd->git_cmd)
108ac313	194	free(cmd->argv);
ba26f296	195
108ac313	196	cmd->argv = sargv;
ba26f296 JS	197	if (s0 >= 0)
	198	dup2(s0, 0), close(s0);
	199	if (s1 >= 0)
	200	dup2(s1, 1), close(s1);
	201	if (s2 >= 0)
	202	dup2(s2, 2), close(s2);
	203	#endif
	204
	205	if (cmd->pid < 0) {
	206	if (need_in)
	207	close_pair(fdin);
	208	else if (cmd->in)
	209	close(cmd->in);
	210	if (need_out)
	211	close_pair(fdout);
	212	else if (cmd->out)
	213	close(cmd->out);
	214	if (need_err)
	215	close_pair(fderr);
0ac77ec3 JS	216	errno = failed_errno;
0ac77ec3 JS	217	return -1;
ba26f296	218	}
4919bf03 SP	219
	220	if (need_in)
	221	close(fdin[0]);
	222	else if (cmd->in)
	223	close(cmd->in);
	224
f4bba25b SP	225	if (need_out)
f4bba25b SP	226	close(fdout[1]);
c20181e3	227	else if (cmd->out)
f4bba25b SP	228	close(cmd->out);
f4bba25b SP	229
f3b33f1d JS	230	if (need_err)
	231	close(fderr[1]);
	232
ebcb5d16 SP	233	return 0;
	234	}
	235
c024beb5	236	static int wait_or_whine(pid_t pid, const char *argv0, int silent_exec_failure)
ebcb5d16	237	{
0ac77ec3 JS	238	int status, code = -1;
	239	pid_t waiting;
	240	int failed_errno = 0;
	241
	242	while ((waiting = waitpid(pid, &status, 0)) < 0 && errno == EINTR)
	243	; /* nothing */
	244
	245	if (waiting < 0) {
	246	failed_errno = errno;
	247	error("waitpid for %s failed: %s", argv0, strerror(errno));
	248	} else if (waiting != pid) {
	249	error("waitpid is confused (%s)", argv0);
	250	} else if (WIFSIGNALED(status)) {
b99d5f40 JS	251	code = WTERMSIG(status);
	252	error("%s died of signal %d", argv0, code);
	253	/*
	254	* This return value is chosen so that code & 0xff
	255	* mimics the exit code that a POSIX shell would report for
	256	* a program that died from this signal.
	257	*/
	258	code -= 128;
0ac77ec3	259	} else if (WIFEXITED(status)) {
b1bf95bb	260	code = WEXITSTATUS(status);
0ac77ec3 JS	261	/*
	262	* Convert special exit code when execvp failed.
	263	*/
	264	if (code == 127) {
	265	code = -1;
	266	failed_errno = ENOENT;
c024beb5 JS	267	if (!silent_exec_failure)
	268	error("cannot run %s: %s", argv0,
	269	strerror(ENOENT));
45c0961c	270	}
0ac77ec3 JS	271	} else {
0ac77ec3 JS	272	error("waitpid is confused (%s)", argv0);
b1bf95bb	273	}
0ac77ec3 JS	274	errno = failed_errno;
0ac77ec3 JS	275	return code;
b1bf95bb	276	}
f1000898	277
2d22c208 JS	278	int finish_command(struct child_process *cmd)
2d22c208 JS	279	{
c024beb5	280	return wait_or_whine(cmd->pid, cmd->argv[0], cmd->silent_exec_failure);
2d22c208 JS	281	}
2d22c208 JS	282
ebcb5d16 SP	283	int run_command(struct child_process *cmd)
	284	{
	285	int code = start_command(cmd);
	286	if (code)
	287	return code;
	288	return finish_command(cmd);
	289	}
	290
1568fea0	291	static void prepare_run_command_v_opt(struct child_process *cmd,
ee493148 AR	292	const char **argv,
ee493148 AR	293	int opt)
1568fea0 AR	294	{
	295	memset(cmd, 0, sizeof(*cmd));
	296	cmd->argv = argv;
	297	cmd->no_stdin = opt & RUN_COMMAND_NO_STDIN ? 1 : 0;
	298	cmd->git_cmd = opt & RUN_GIT_CMD ? 1 : 0;
	299	cmd->stdout_to_stderr = opt & RUN_COMMAND_STDOUT_TO_STDERR ? 1 : 0;
c024beb5	300	cmd->silent_exec_failure = opt & RUN_SILENT_EXEC_FAILURE ? 1 : 0;
1568fea0 AR	301	}
1568fea0 AR	302
f1000898 SP	303	int run_command_v_opt(const char **argv, int opt)
	304	{
	305	struct child_process cmd;
1568fea0 AR	306	prepare_run_command_v_opt(&cmd, argv, opt);
	307	return run_command(&cmd);
	308	}
	309
ee493148 AR	310	int run_command_v_opt_cd_env(const char *argv, int opt, const char dir, const char const env)
	311	{
	312	struct child_process cmd;
	313	prepare_run_command_v_opt(&cmd, argv, opt);
	314	cmd.dir = dir;
	315	cmd.env = env;
	316	return run_command(&cmd);
	317	}
2d22c208	318
618ebe9f JS	319	#ifdef __MINGW32__
	320	static __stdcall unsigned run_thread(void *data)
	321	{
	322	struct async *async = data;
	323	return async->proc(async->fd_for_proc, async->data);
	324	}
	325	#endif
	326
2d22c208 JS	327	int start_async(struct async *async)
	328	{
	329	int pipe_out[2];
	330
	331	if (pipe(pipe_out) < 0)
	332	return error("cannot create pipe: %s", strerror(errno));
618ebe9f	333	async->out = pipe_out[0];
2d22c208	334
618ebe9f	335	#ifndef __MINGW32__
2c3766f0 AM	336	/* Flush stdio before fork() to avoid cloning buffers */
	337	fflush(NULL);
	338
2d22c208 JS	339	async->pid = fork();
	340	if (async->pid < 0) {
	341	error("fork (async) failed: %s", strerror(errno));
	342	close_pair(pipe_out);
	343	return -1;
	344	}
	345	if (!async->pid) {
	346	close(pipe_out[0]);
	347	exit(!!async->proc(pipe_out[1], async->data));
	348	}
2d22c208	349	close(pipe_out[1]);
618ebe9f JS	350	#else
	351	async->fd_for_proc = pipe_out[1];
	352	async->tid = (HANDLE) _beginthreadex(NULL, 0, run_thread, async, 0, NULL);
	353	if (!async->tid) {
	354	error("cannot create thread: %s", strerror(errno));
	355	close_pair(pipe_out);
	356	return -1;
	357	}
	358	#endif
2d22c208 JS	359	return 0;
	360	}
	361
	362	int finish_async(struct async *async)
	363	{
618ebe9f	364	#ifndef __MINGW32__
c024beb5	365	int ret = wait_or_whine(async->pid, "child process", 0);
618ebe9f JS	366	#else
	367	DWORD ret = 0;
	368	if (WaitForSingleObject(async->tid, INFINITE) != WAIT_OBJECT_0)
	369	ret = error("waiting for thread failed: %lu", GetLastError());
	370	else if (!GetExitCodeThread(async->tid, &ret))
	371	ret = error("cannot get thread exit code: %lu", GetLastError());
	372	CloseHandle(async->tid);
	373	#endif
2d22c208 JS	374	return ret;
2d22c208 JS	375	}
ae98a008 SB	376
	377	int run_hook(const char index_file, const char name, ...)
	378	{
	379	struct child_process hook;
14e6298f	380	const char *argv = NULL, env[2];
ae98a008 SB	381	char index[PATH_MAX];
	382	va_list args;
	383	int ret;
14e6298f	384	size_t i = 0, alloc = 0;
ae98a008	385
cf94ca8e SB	386	if (access(git_path("hooks/%s", name), X_OK) < 0)
	387	return 0;
	388
ae98a008	389	va_start(args, name);
14e6298f SB	390	ALLOC_GROW(argv, i + 1, alloc);
	391	argv[i++] = git_path("hooks/%s", name);
	392	while (argv[i-1]) {
	393	ALLOC_GROW(argv, i + 1, alloc);
	394	argv[i++] = va_arg(args, const char *);
	395	}
ae98a008 SB	396	va_end(args);
ae98a008 SB	397
ae98a008 SB	398	memset(&hook, 0, sizeof(hook));
	399	hook.argv = argv;
	400	hook.no_stdin = 1;
	401	hook.stdout_to_stderr = 1;
	402	if (index_file) {
	403	snprintf(index, sizeof(index), "GIT_INDEX_FILE=%s", index_file);
	404	env[0] = index;
	405	env[1] = NULL;
	406	hook.env = env;
	407	}
	408
0ac77ec3	409	ret = run_command(&hook);
14e6298f	410	free(argv);
ae98a008 SB	411	return ret;
ae98a008 SB	412	}