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	#include "cache.h"
	#include "run-command.h"
	#include "exec-cmd.h"
	#include "sigchain.h"
	#include "strvec.h"
	#include "thread-utils.h"
	#include "strbuf.h"
	#include "string-list.h"
	#include "quote.h"
	#include "config.h"

	void child_process_init(struct child_process *child)
	{
	struct child_process blank = CHILD_PROCESS_INIT;
	memcpy(child, &blank, sizeof(*child));
	}

	void child_process_clear(struct child_process *child)
	{
	strvec_clear(&child->args);
	strvec_clear(&child->env_array);
	}

	struct child_to_clean {
	pid_t pid;
	struct child_process *process;
	struct child_to_clean *next;
	};
	static struct child_to_clean *children_to_clean;
	static int installed_child_cleanup_handler;

	static void cleanup_children(int sig, int in_signal)
	{
	struct child_to_clean *children_to_wait_for = NULL;

	while (children_to_clean) {
	struct child_to_clean *p = children_to_clean;
	children_to_clean = p->next;

	if (p->process && !in_signal) {
	struct child_process *process = p->process;
	if (process->clean_on_exit_handler) {
	trace_printf(
	"trace: run_command: running exit handler for pid %"
	PRIuMAX, (uintmax_t)p->pid
	);
	process->clean_on_exit_handler(process);
	}
	}

	kill(p->pid, sig);

	if (p->process && p->process->wait_after_clean) {
	p->next = children_to_wait_for;
	children_to_wait_for = p;
	} else {
	if (!in_signal)
	free(p);
	}
	}

	while (children_to_wait_for) {
	struct child_to_clean *p = children_to_wait_for;
	children_to_wait_for = p->next;

	while (waitpid(p->pid, NULL, 0) < 0 && errno == EINTR)
	; /* spin waiting for process exit or error */

	if (!in_signal)
	free(p);
	}
	}

	static void cleanup_children_on_signal(int sig)
	{
	cleanup_children(sig, 1);
	sigchain_pop(sig);
	raise(sig);
	}

	static void cleanup_children_on_exit(void)
	{
	cleanup_children(SIGTERM, 0);
	}

	static void mark_child_for_cleanup(pid_t pid, struct child_process *process)
	{
	struct child_to_clean p = xmalloc(sizeof(p));
	p->pid = pid;
	p->process = process;
	p->next = children_to_clean;
	children_to_clean = p;

	if (!installed_child_cleanup_handler) {
	atexit(cleanup_children_on_exit);
	sigchain_push_common(cleanup_children_on_signal);
	installed_child_cleanup_handler = 1;
	}
	}

	static void clear_child_for_cleanup(pid_t pid)
	{
	struct child_to_clean **pp;

	for (pp = &children_to_clean; pp; pp = &(pp)->next) {
	struct child_to_clean clean_me = pp;

	if (clean_me->pid == pid) {
	*pp = clean_me->next;
	free(clean_me);
	return;
	}
	}
	}

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

	int is_executable(const char *name)
	{
	struct stat st;

	if (stat(name, &st) \|\| /* stat, not lstat */
	!S_ISREG(st.st_mode))
	return 0;

	#if defined(GIT_WINDOWS_NATIVE)
	/*
	* On Windows there is no executable bit. The file extension
	* indicates whether it can be run as an executable, and Git
	* has special-handling to detect scripts and launch them
	* through the indicated script interpreter. We test for the
	* file extension first because virus scanners may make
	* it quite expensive to open many files.
	*/
	if (ends_with(name, ".exe"))
	return S_IXUSR;

	{
	/*
	* Now that we know it does not have an executable extension,
	* peek into the file instead.
	*/
	char buf[3] = { 0 };
	int n;
	int fd = open(name, O_RDONLY);
	st.st_mode &= ~S_IXUSR;
	if (fd >= 0) {
	n = read(fd, buf, 2);
	if (n == 2)
	/* look for a she-bang */
	if (!strcmp(buf, "#!"))
	st.st_mode \|= S_IXUSR;
	close(fd);
	}
	}
	#endif
	return st.st_mode & S_IXUSR;
	}

	/*
	* Search $PATH for a command. This emulates the path search that
	* execvp would perform, without actually executing the command so it
	* can be used before fork() to prepare to run a command using
	* execve() or after execvp() to diagnose why it failed.
	*
	* The caller should ensure that file contains no directory
	* separators.
	*
	* Returns the path to the command, as found in $PATH or NULL if the
	* command could not be found. The caller inherits ownership of the memory
	* used to store the resultant path.
	*
	* This should not be used on Windows, where the $PATH search rules
	* are more complicated (e.g., a search for "foo" should find
	* "foo.exe").
	*/
	static char locate_in_PATH(const char file)
	{
	const char *p = getenv("PATH");
	struct strbuf buf = STRBUF_INIT;

	if (!p \|\| !*p)
	return NULL;

	while (1) {
	const char *end = strchrnul(p, ':');

	strbuf_reset(&buf);

	/* POSIX specifies an empty entry as the current directory. */
	if (end != p) {
	strbuf_add(&buf, p, end - p);
	strbuf_addch(&buf, '/');
	}
	strbuf_addstr(&buf, file);

	if (is_executable(buf.buf))
	return strbuf_detach(&buf, NULL);

	if (!*end)
	break;
	p = end + 1;
	}

	strbuf_release(&buf);
	return NULL;
	}

	static int exists_in_PATH(const char *file)
	{
	char *r = locate_in_PATH(file);
	int found = r != NULL;
	free(r);
	return found;
	}

	int sane_execvp(const char file, char const argv[])
	{
	#ifndef GIT_WINDOWS_NATIVE
	/*
	* execvp() doesn't return, so we all we can do is tell trace2
	* what we are about to do and let it leave a hint in the log
	* (unless of course the execvp() fails).
	*
	* we skip this for Windows because the compat layer already
	* has to emulate the execvp() call anyway.
	*/
	int exec_id = trace2_exec(file, (const char **)argv);
	#endif

	if (!execvp(file, argv))
	return 0; /* cannot happen ;-) */

	#ifndef GIT_WINDOWS_NATIVE
	{
	int ec = errno;
	trace2_exec_result(exec_id, ec);
	errno = ec;
	}
	#endif

	/*
	* When a command can't be found because one of the directories
	* listed in $PATH is unsearchable, execvp reports EACCES, but
	* careful usability testing (read: analysis of occasional bug
	* reports) reveals that "No such file or directory" is more
	* intuitive.
	*
	* We avoid commands with "/", because execvp will not do $PATH
	* lookups in that case.
	*
	* The reassignment of EACCES to errno looks like a no-op below,
	* but we need to protect against exists_in_PATH overwriting errno.
	*/
	if (errno == EACCES && !strchr(file, '/'))
	errno = exists_in_PATH(file) ? EACCES : ENOENT;
	else if (errno == ENOTDIR && !strchr(file, '/'))
	errno = ENOENT;
	return -1;
	}

	static const char *prepare_shell_cmd(struct strvec out, const char **argv)
	{
	if (!argv[0])
	BUG("shell command is empty");

	if (strcspn(argv[0], "\|&;<>()$`\\\"' \t\n*?[#~=%") != strlen(argv[0])) {
	#ifndef GIT_WINDOWS_NATIVE
	strvec_push(out, SHELL_PATH);
	#else
	strvec_push(out, "sh");
	#endif
	strvec_push(out, "-c");

	/*
	* If we have no extra arguments, we do not even need to
	* bother with the "$@" magic.
	*/
	if (!argv[1])
	strvec_push(out, argv[0]);
	else
	strvec_pushf(out, "%s \"$@\"", argv[0]);
	}

	strvec_pushv(out, argv);
	return out->v;
	}

	#ifndef GIT_WINDOWS_NATIVE
	static int child_notifier = -1;

	enum child_errcode {
	CHILD_ERR_CHDIR,
	CHILD_ERR_DUP2,
	CHILD_ERR_CLOSE,
	CHILD_ERR_SIGPROCMASK,
	CHILD_ERR_ENOENT,
	CHILD_ERR_SILENT,
	CHILD_ERR_ERRNO
	};

	struct child_err {
	enum child_errcode err;
	int syserr; /* errno */
	};

	static void child_die(enum child_errcode err)
	{
	struct child_err buf;

	buf.err = err;
	buf.syserr = errno;

	/* write(2) on buf smaller than PIPE_BUF (min 512) is atomic: */
	xwrite(child_notifier, &buf, sizeof(buf));
	_exit(1);
	}

	static void child_dup2(int fd, int to)
	{
	if (dup2(fd, to) < 0)
	child_die(CHILD_ERR_DUP2);
	}

	static void child_close(int fd)
	{
	if (close(fd))
	child_die(CHILD_ERR_CLOSE);
	}

	static void child_close_pair(int fd[2])
	{
	child_close(fd[0]);
	child_close(fd[1]);
	}

	/*
	* parent will make it look like the child spewed a fatal error and died
	* this is needed to prevent changes to t0061.
	*/
	static void fake_fatal(const char *err, va_list params)
	{
	vreportf("fatal: ", err, params);
	}

	static void child_error_fn(const char *err, va_list params)
	{
	const char msg[] = "error() should not be called in child\n";
	xwrite(2, msg, sizeof(msg) - 1);
	}

	static void child_warn_fn(const char *err, va_list params)
	{
	const char msg[] = "warn() should not be called in child\n";
	xwrite(2, msg, sizeof(msg) - 1);
	}

	static void NORETURN child_die_fn(const char *err, va_list params)
	{
	const char msg[] = "die() should not be called in child\n";
	xwrite(2, msg, sizeof(msg) - 1);
	_exit(2);
	}

	/* this runs in the parent process */
	static void child_err_spew(struct child_process cmd, struct child_err cerr)
	{
	static void (old_errfn)(const char err, va_list params);

	old_errfn = get_error_routine();
	set_error_routine(fake_fatal);
	errno = cerr->syserr;

	switch (cerr->err) {
	case CHILD_ERR_CHDIR:
	error_errno("exec '%s': cd to '%s' failed",
	cmd->argv[0], cmd->dir);
	break;
	case CHILD_ERR_DUP2:
	error_errno("dup2() in child failed");
	break;
	case CHILD_ERR_CLOSE:
	error_errno("close() in child failed");
	break;
	case CHILD_ERR_SIGPROCMASK:
	error_errno("sigprocmask failed restoring signals");
	break;
	case CHILD_ERR_ENOENT:
	error_errno("cannot run %s", cmd->argv[0]);
	break;
	case CHILD_ERR_SILENT:
	break;
	case CHILD_ERR_ERRNO:
	error_errno("cannot exec '%s'", cmd->argv[0]);
	break;
	}
	set_error_routine(old_errfn);
	}

	static int prepare_cmd(struct strvec out, const struct child_process cmd)
	{
	if (!cmd->argv[0])
	BUG("command is empty");

	/*
	* Add SHELL_PATH so in the event exec fails with ENOEXEC we can
	* attempt to interpret the command with 'sh'.
	*/
	strvec_push(out, SHELL_PATH);

	if (cmd->git_cmd) {
	prepare_git_cmd(out, cmd->argv);
	} else if (cmd->use_shell) {
	prepare_shell_cmd(out, cmd->argv);
	} else {
	strvec_pushv(out, cmd->argv);
	}

	/*
	* If there are no dir separator characters in the command then perform
	* a path lookup and use the resolved path as the command to exec. If
	* there are dir separator characters, we have exec attempt to invoke
	* the command directly.
	*/
	if (!has_dir_sep(out->v[1])) {
	char *program = locate_in_PATH(out->v[1]);
	if (program) {
	free((char *)out->v[1]);
	out->v[1] = program;
	} else {
	strvec_clear(out);
	errno = ENOENT;
	return -1;
	}
	}

	return 0;
	}

	static char *prep_childenv(const char const *deltaenv)
	{
	extern char **environ;
	char **childenv;
	struct string_list env = STRING_LIST_INIT_DUP;
	struct strbuf key = STRBUF_INIT;
	const char const p;
	int i;

	/* Construct a sorted string list consisting of the current environ */
	for (p = (const char const ) environ; p && *p; p++) {
	const char equals = strchr(p, '=');

	if (equals) {
	strbuf_reset(&key);
	strbuf_add(&key, p, equals - p);
	string_list_append(&env, key.buf)->util = (void ) p;
	} else {
	string_list_append(&env, p)->util = (void ) *p;
	}
	}
	string_list_sort(&env);

	/* Merge in 'deltaenv' with the current environ */
	for (p = deltaenv; p && *p; p++) {
	const char equals = strchr(p, '=');

	if (equals) {
	/* ('key=value'), insert or replace entry */
	strbuf_reset(&key);
	strbuf_add(&key, p, equals - p);
	string_list_insert(&env, key.buf)->util = (void ) p;
	} else {
	/* otherwise ('key') remove existing entry */
	string_list_remove(&env, *p, 0);
	}
	}

	/* Create an array of 'char ' to be used as the childenv /
	ALLOC_ARRAY(childenv, env.nr + 1);
	for (i = 0; i < env.nr; i++)
	childenv[i] = env.items[i].util;
	childenv[env.nr] = NULL;

	string_list_clear(&env, 0);
	strbuf_release(&key);
	return childenv;
	}

	struct atfork_state {
	#ifndef NO_PTHREADS
	int cs;
	#endif
	sigset_t old;
	};

	#define CHECK_BUG(err, msg) \
	do { \
	int e = (err); \
	if (e) \
	BUG("%s: %s", msg, strerror(e)); \
	} while(0)

	static void atfork_prepare(struct atfork_state *as)
	{
	sigset_t all;

	if (sigfillset(&all))
	die_errno("sigfillset");
	#ifdef NO_PTHREADS
	if (sigprocmask(SIG_SETMASK, &all, &as->old))
	die_errno("sigprocmask");
	#else
	CHECK_BUG(pthread_sigmask(SIG_SETMASK, &all, &as->old),
	"blocking all signals");
	CHECK_BUG(pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &as->cs),
	"disabling cancellation");
	#endif
	}

	static void atfork_parent(struct atfork_state *as)
	{
	#ifdef NO_PTHREADS
	if (sigprocmask(SIG_SETMASK, &as->old, NULL))
	die_errno("sigprocmask");
	#else
	CHECK_BUG(pthread_setcancelstate(as->cs, NULL),
	"re-enabling cancellation");
	CHECK_BUG(pthread_sigmask(SIG_SETMASK, &as->old, NULL),
	"restoring signal mask");
	#endif
	}
	#endif /* GIT_WINDOWS_NATIVE */

	static inline void set_cloexec(int fd)
	{
	int flags = fcntl(fd, F_GETFD);
	if (flags >= 0)
	fcntl(fd, F_SETFD, flags \| FD_CLOEXEC);
	}

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

	while ((waiting = waitpid(pid, &status, 0)) < 0 && errno == EINTR)
	; /* nothing */
	if (in_signal) {
	if (WIFEXITED(status))
	code = WEXITSTATUS(status);
	return code;
	}

	if (waiting < 0) {
	failed_errno = errno;
	error_errno("waitpid for %s failed", argv0);
	} else if (waiting != pid) {
	error("waitpid is confused (%s)", argv0);
	} else if (WIFSIGNALED(status)) {
	code = WTERMSIG(status);
	if (code != SIGINT && code != SIGQUIT && code != SIGPIPE)
	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);
	} else {
	error("waitpid is confused (%s)", argv0);
	}

	clear_child_for_cleanup(pid);

	errno = failed_errno;
	return code;
	}

	static void trace_add_env(struct strbuf dst, const char const *deltaenv)
	{
	struct string_list envs = STRING_LIST_INIT_DUP;
	const char const e;
	int i;
	int printed_unset = 0;

	/* Last one wins, see run-command.c:prep_childenv() for context */
	for (e = deltaenv; e && *e; e++) {
	struct strbuf key = STRBUF_INIT;
	char equals = strchr(e, '=');

	if (equals) {
	strbuf_add(&key, e, equals - e);
	string_list_insert(&envs, key.buf)->util = equals + 1;
	} else {
	string_list_insert(&envs, *e)->util = NULL;
	}
	strbuf_release(&key);
	}

	/* "unset X Y...;" */
	for (i = 0; i < envs.nr; i++) {
	const char *var = envs.items[i].string;
	const char *val = envs.items[i].util;

	if (val \|\| !getenv(var))
	continue;

	if (!printed_unset) {
	strbuf_addstr(dst, " unset");
	printed_unset = 1;
	}
	strbuf_addf(dst, " %s", var);
	}
	if (printed_unset)
	strbuf_addch(dst, ';');

	/* ... followed by "A=B C=D ..." */
	for (i = 0; i < envs.nr; i++) {
	const char *var = envs.items[i].string;
	const char *val = envs.items[i].util;
	const char *oldval;

	if (!val)
	continue;

	oldval = getenv(var);
	if (oldval && !strcmp(val, oldval))
	continue;

	strbuf_addf(dst, " %s=", var);
	sq_quote_buf_pretty(dst, val);
	}
	string_list_clear(&envs, 0);
	}

	static void trace_run_command(const struct child_process *cp)
	{
	struct strbuf buf = STRBUF_INIT;

	if (!trace_want(&trace_default_key))
	return;

	strbuf_addstr(&buf, "trace: run_command:");
	if (cp->dir) {
	strbuf_addstr(&buf, " cd ");
	sq_quote_buf_pretty(&buf, cp->dir);
	strbuf_addch(&buf, ';');
	}
	/*
	* The caller is responsible for initializing cp->env from
	* cp->env_array if needed. We only check one place.
	*/
	if (cp->env)
	trace_add_env(&buf, cp->env);
	if (cp->git_cmd)
	strbuf_addstr(&buf, " git");
	sq_quote_argv_pretty(&buf, cp->argv);

	trace_printf("%s", buf.buf);
	strbuf_release(&buf);
	}

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

	if (!cmd->argv)
	cmd->argv = cmd->args.v;
	if (!cmd->env)
	cmd->env = cmd->env_array.v;

	/*
	* 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);
	str = "standard input";
	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);
	str = "standard output";
	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);
	str = "standard error";
	fail_pipe:
	error("cannot create %s pipe for %s: %s",
	str, cmd->argv[0], strerror(failed_errno));
	child_process_clear(cmd);
	errno = failed_errno;
	return -1;
	}
	cmd->err = fderr[0];
	}

	trace2_child_start(cmd);
	trace_run_command(cmd);

	fflush(NULL);

	#ifndef GIT_WINDOWS_NATIVE
	{
	int notify_pipe[2];
	int null_fd = -1;
	char **childenv;
	struct strvec argv = STRVEC_INIT;
	struct child_err cerr;
	struct atfork_state as;

	if (prepare_cmd(&argv, cmd) < 0) {
	failed_errno = errno;
	cmd->pid = -1;
	if (!cmd->silent_exec_failure)
	error_errno("cannot run %s", cmd->argv[0]);
	goto end_of_spawn;
	}

	if (pipe(notify_pipe))
	notify_pipe[0] = notify_pipe[1] = -1;

	if (cmd->no_stdin \|\| cmd->no_stdout \|\| cmd->no_stderr) {
	null_fd = open("/dev/null", O_RDWR \| O_CLOEXEC);
	if (null_fd < 0)
	die_errno(_("open /dev/null failed"));
	set_cloexec(null_fd);
	}

	childenv = prep_childenv(cmd->env);
	atfork_prepare(&as);

	/*
	* NOTE: In order to prevent deadlocking when using threads special
	* care should be taken with the function calls made in between the
	* fork() and exec() calls. No calls should be made to functions which
	* require acquiring a lock (e.g. malloc) as the lock could have been
	* held by another thread at the time of forking, causing the lock to
	* never be released in the child process. This means only
	* Async-Signal-Safe functions are permitted in the child.
	*/
	cmd->pid = fork();
	failed_errno = errno;
	if (!cmd->pid) {
	int sig;
	/*
	* Ensure the default die/error/warn routines do not get
	* called, they can take stdio locks and malloc.
	*/
	set_die_routine(child_die_fn);
	set_error_routine(child_error_fn);
	set_warn_routine(child_warn_fn);

	close(notify_pipe[0]);
	set_cloexec(notify_pipe[1]);
	child_notifier = notify_pipe[1];

	if (cmd->no_stdin)
	child_dup2(null_fd, 0);
	else if (need_in) {
	child_dup2(fdin[0], 0);
	child_close_pair(fdin);
	} else if (cmd->in) {
	child_dup2(cmd->in, 0);
	child_close(cmd->in);
	}

	if (cmd->no_stderr)
	child_dup2(null_fd, 2);
	else if (need_err) {
	child_dup2(fderr[1], 2);
	child_close_pair(fderr);
	} else if (cmd->err > 1) {
	child_dup2(cmd->err, 2);
	child_close(cmd->err);
	}

	if (cmd->no_stdout)
	child_dup2(null_fd, 1);
	else if (cmd->stdout_to_stderr)
	child_dup2(2, 1);
	else if (need_out) {
	child_dup2(fdout[1], 1);
	child_close_pair(fdout);
	} else if (cmd->out > 1) {
	child_dup2(cmd->out, 1);
	child_close(cmd->out);
	}

	if (cmd->dir && chdir(cmd->dir))
	child_die(CHILD_ERR_CHDIR);

	/*
	* restore default signal handlers here, in case
	* we catch a signal right before execve below
	*/
	for (sig = 1; sig < NSIG; sig++) {
	/* ignored signals get reset to SIG_DFL on execve */
	if (signal(sig, SIG_DFL) == SIG_IGN)
	signal(sig, SIG_IGN);
	}

	if (sigprocmask(SIG_SETMASK, &as.old, NULL) != 0)
	child_die(CHILD_ERR_SIGPROCMASK);

	/*
	* Attempt to exec using the command and arguments starting at
	* argv.argv[1]. argv.argv[0] contains SHELL_PATH which will
	* be used in the event exec failed with ENOEXEC at which point
	* we will try to interpret the command using 'sh'.
	*/
	execve(argv.v[1], (char const ) argv.v + 1,
	(char const ) childenv);
	if (errno == ENOEXEC)
	execve(argv.v[0], (char const ) argv.v,
	(char const ) childenv);

	if (errno == ENOENT) {
	if (cmd->silent_exec_failure)
	child_die(CHILD_ERR_SILENT);
	child_die(CHILD_ERR_ENOENT);
	} else {
	child_die(CHILD_ERR_ERRNO);
	}
	}
	atfork_parent(&as);
	if (cmd->pid < 0)
	error_errno("cannot fork() for %s", cmd->argv[0]);
	else if (cmd->clean_on_exit)
	mark_child_for_cleanup(cmd->pid, cmd);

	/*
	* Wait for child's exec. If the exec succeeds (or if fork()
	* failed), EOF is seen immediately by the parent. Otherwise, the
	* child process sends a child_err struct.
	* Note that use of this infrastructure is completely advisory,
	* therefore, we keep error checks minimal.
	*/
	close(notify_pipe[1]);
	if (xread(notify_pipe[0], &cerr, sizeof(cerr)) == sizeof(cerr)) {
	/*
	* At this point we know that fork() succeeded, but exec()
	* failed. Errors have been reported to our stderr.
	*/
	wait_or_whine(cmd->pid, cmd->argv[0], 0);
	child_err_spew(cmd, &cerr);
	failed_errno = errno;
	cmd->pid = -1;
	}
	close(notify_pipe[0]);

	if (null_fd >= 0)
	close(null_fd);
	strvec_clear(&argv);
	free(childenv);
	}
	end_of_spawn:

	#else
	{
	int fhin = 0, fhout = 1, fherr = 2;
	const char **sargv = cmd->argv;
	struct strvec nargv = STRVEC_INIT;

	if (cmd->no_stdin)
	fhin = open("/dev/null", O_RDWR);
	else if (need_in)
	fhin = dup(fdin[0]);
	else if (cmd->in)
	fhin = dup(cmd->in);

	if (cmd->no_stderr)
	fherr = open("/dev/null", O_RDWR);
	else if (need_err)
	fherr = dup(fderr[1]);
	else if (cmd->err > 2)
	fherr = dup(cmd->err);

	if (cmd->no_stdout)
	fhout = open("/dev/null", O_RDWR);
	else if (cmd->stdout_to_stderr)
	fhout = dup(fherr);
	else if (need_out)
	fhout = dup(fdout[1]);
	else if (cmd->out > 1)
	fhout = dup(cmd->out);

	if (cmd->git_cmd)
	cmd->argv = prepare_git_cmd(&nargv, cmd->argv);
	else if (cmd->use_shell)
	cmd->argv = prepare_shell_cmd(&nargv, cmd->argv);

	cmd->pid = mingw_spawnvpe(cmd->argv[0], cmd->argv, (char**) cmd->env,
	cmd->dir, fhin, fhout, fherr);
	failed_errno = errno;
	if (cmd->pid < 0 && (!cmd->silent_exec_failure \|\| errno != ENOENT))
	error_errno("cannot spawn %s", cmd->argv[0]);
	if (cmd->clean_on_exit && cmd->pid >= 0)
	mark_child_for_cleanup(cmd->pid, cmd);

	strvec_clear(&nargv);
	cmd->argv = sargv;
	if (fhin != 0)
	close(fhin);
	if (fhout != 1)
	close(fhout);
	if (fherr != 2)
	close(fherr);
	}
	#endif

	if (cmd->pid < 0) {
	trace2_child_exit(cmd, -1);

	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);
	else if (cmd->err)
	close(cmd->err);
	child_process_clear(cmd);
	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]);
	else if (cmd->err)
	close(cmd->err);

	return 0;
	}

	int finish_command(struct child_process *cmd)
	{
	int ret = wait_or_whine(cmd->pid, cmd->argv[0], 0);
	trace2_child_exit(cmd, ret);
	child_process_clear(cmd);
	invalidate_lstat_cache();
	return ret;
	}

	int finish_command_in_signal(struct child_process *cmd)
	{
	int ret = wait_or_whine(cmd->pid, cmd->argv[0], 1);
	trace2_child_exit(cmd, ret);
	return ret;
	}


	int run_command(struct child_process *cmd)
	{
	int code;

	if (cmd->out < 0 \|\| cmd->err < 0)
	BUG("run_command with a pipe can cause deadlock");

	code = start_command(cmd);
	if (code)
	return code;
	return finish_command(cmd);
	}

	int run_command_v_opt(const char **argv, int opt)
	{
	return run_command_v_opt_cd_env(argv, opt, NULL, NULL);
	}

	int run_command_v_opt_tr2(const char *argv, int opt, const char tr2_class)
	{
	return run_command_v_opt_cd_env_tr2(argv, opt, NULL, NULL, tr2_class);
	}

	int run_command_v_opt_cd_env(const char *argv, int opt, const char dir, const char const env)
	{
	return run_command_v_opt_cd_env_tr2(argv, opt, dir, env, NULL);
	}

	int run_command_v_opt_cd_env_tr2(const char *argv, int opt, const char dir,
	const char const env, const char *tr2_class)
	{
	struct child_process cmd = CHILD_PROCESS_INIT;
	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;
	cmd.use_shell = opt & RUN_USING_SHELL ? 1 : 0;
	cmd.clean_on_exit = opt & RUN_CLEAN_ON_EXIT ? 1 : 0;
	cmd.wait_after_clean = opt & RUN_WAIT_AFTER_CLEAN ? 1 : 0;
	cmd.dir = dir;
	cmd.env = env;
	cmd.trace2_child_class = tr2_class;
	return run_command(&cmd);
	}

	#ifndef NO_PTHREADS
	static pthread_t main_thread;
	static int main_thread_set;
	static pthread_key_t async_key;
	static pthread_key_t async_die_counter;

	static void run_thread(void data)
	{
	struct async *async = data;
	intptr_t ret;

	if (async->isolate_sigpipe) {
	sigset_t mask;
	sigemptyset(&mask);
	sigaddset(&mask, SIGPIPE);
	if (pthread_sigmask(SIG_BLOCK, &mask, NULL) < 0) {
	ret = error("unable to block SIGPIPE in async thread");
	return (void *)ret;
	}
	}

	pthread_setspecific(async_key, async);
	ret = async->proc(async->proc_in, async->proc_out, async->data);
	return (void *)ret;
	}

	static NORETURN void die_async(const char *err, va_list params)
	{
	vreportf("fatal: ", err, params);

	if (in_async()) {
	struct async *async = pthread_getspecific(async_key);
	if (async->proc_in >= 0)
	close(async->proc_in);
	if (async->proc_out >= 0)
	close(async->proc_out);
	pthread_exit((void *)128);
	}

	exit(128);
	}

	static int async_die_is_recursing(void)
	{
	void *ret = pthread_getspecific(async_die_counter);
	pthread_setspecific(async_die_counter, (void *)1);
	return ret != NULL;
	}

	int in_async(void)
	{
	if (!main_thread_set)
	return 0; /* no asyncs started yet */
	return !pthread_equal(main_thread, pthread_self());
	}

	static void NORETURN async_exit(int code)
	{
	pthread_exit((void *)(intptr_t)code);
	}

	#else

	static struct {
	void (**handlers)(void);
	size_t nr;
	size_t alloc;
	} git_atexit_hdlrs;

	static int git_atexit_installed;

	static void git_atexit_dispatch(void)
	{
	size_t i;

	for (i=git_atexit_hdlrs.nr ; i ; i--)
	git_atexit_hdlrs.handlers[i-1]();
	}

	static void git_atexit_clear(void)
	{
	free(git_atexit_hdlrs.handlers);
	memset(&git_atexit_hdlrs, 0, sizeof(git_atexit_hdlrs));
	git_atexit_installed = 0;
	}

	#undef atexit
	int git_atexit(void (*handler)(void))
	{
	ALLOC_GROW(git_atexit_hdlrs.handlers, git_atexit_hdlrs.nr + 1, git_atexit_hdlrs.alloc);
	git_atexit_hdlrs.handlers[git_atexit_hdlrs.nr++] = handler;
	if (!git_atexit_installed) {
	if (atexit(&git_atexit_dispatch))
	return -1;
	git_atexit_installed = 1;
	}
	return 0;
	}
	#define atexit git_atexit

	static int process_is_async;
	int in_async(void)
	{
	return process_is_async;
	}

	static void NORETURN async_exit(int code)
	{
	exit(code);
	}

	#endif

	void check_pipe(int err)
	{
	if (err == EPIPE) {
	if (in_async())
	async_exit(141);

	signal(SIGPIPE, SIG_DFL);
	raise(SIGPIPE);
	/* Should never happen, but just in case... */
	exit(141);
	}
	}

	int start_async(struct async *async)
	{
	int need_in, need_out;
	int fdin[2], fdout[2];
	int proc_in, proc_out;

	need_in = async->in < 0;
	if (need_in) {
	if (pipe(fdin) < 0) {
	if (async->out > 0)
	close(async->out);
	return error_errno("cannot create pipe");
	}
	async->in = fdin[1];
	}

	need_out = async->out < 0;
	if (need_out) {
	if (pipe(fdout) < 0) {
	if (need_in)
	close_pair(fdin);
	else if (async->in)
	close(async->in);
	return error_errno("cannot create pipe");
	}
	async->out = fdout[0];
	}

	if (need_in)
	proc_in = fdin[0];
	else if (async->in)
	proc_in = async->in;
	else
	proc_in = -1;

	if (need_out)
	proc_out = fdout[1];
	else if (async->out)
	proc_out = async->out;
	else
	proc_out = -1;

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

	async->pid = fork();
	if (async->pid < 0) {
	error_errno("fork (async) failed");
	goto error;
	}
	if (!async->pid) {
	if (need_in)
	close(fdin[1]);
	if (need_out)
	close(fdout[0]);
	git_atexit_clear();
	process_is_async = 1;
	exit(!!async->proc(proc_in, proc_out, async->data));
	}

	mark_child_for_cleanup(async->pid, NULL);

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

	if (need_out)
	close(fdout[1]);
	else if (async->out)
	close(async->out);
	#else
	if (!main_thread_set) {
	/*
	* We assume that the first time that start_async is called
	* it is from the main thread.
	*/
	main_thread_set = 1;
	main_thread = pthread_self();
	pthread_key_create(&async_key, NULL);
	pthread_key_create(&async_die_counter, NULL);
	set_die_routine(die_async);
	set_die_is_recursing_routine(async_die_is_recursing);
	}

	if (proc_in >= 0)
	set_cloexec(proc_in);
	if (proc_out >= 0)
	set_cloexec(proc_out);
	async->proc_in = proc_in;
	async->proc_out = proc_out;
	{
	int err = pthread_create(&async->tid, NULL, run_thread, async);
	if (err) {
	error(_("cannot create async thread: %s"), strerror(err));
	goto error;
	}
	}
	#endif
	return 0;

	error:
	if (need_in)
	close_pair(fdin);
	else if (async->in)
	close(async->in);

	if (need_out)
	close_pair(fdout);
	else if (async->out)
	close(async->out);
	return -1;
	}

	int finish_async(struct async *async)
	{
	#ifdef NO_PTHREADS
	int ret = wait_or_whine(async->pid, "child process", 0);

	invalidate_lstat_cache();

	return ret;
	#else
	void ret = (void )(intptr_t)(-1);

	if (pthread_join(async->tid, &ret))
	error("pthread_join failed");
	invalidate_lstat_cache();
	return (int)(intptr_t)ret;

	#endif
	}

	int async_with_fork(void)
	{
	#ifdef NO_PTHREADS
	return 1;
	#else
	return 0;
	#endif
	}

	const char find_hook(const char name)
	{
	static struct strbuf path = STRBUF_INIT;

	strbuf_reset(&path);
	strbuf_git_path(&path, "hooks/%s", name);
	if (access(path.buf, X_OK) < 0) {
	int err = errno;

	#ifdef STRIP_EXTENSION
	strbuf_addstr(&path, STRIP_EXTENSION);
	if (access(path.buf, X_OK) >= 0)
	return path.buf;
	if (errno == EACCES)
	err = errno;
	#endif

	if (err == EACCES && advice_ignored_hook) {
	static struct string_list advise_given = STRING_LIST_INIT_DUP;

	if (!string_list_lookup(&advise_given, name)) {
	string_list_insert(&advise_given, name);
	advise(_("The '%s' hook was ignored because "
	"it's not set as executable.\n"
	"You can disable this warning with "
	"`git config advice.ignoredHook false`."),
	path.buf);
	}
	}
	return NULL;
	}
	return path.buf;
	}

	int run_hook_ve(const char const env, const char *name, va_list args)
	{
	struct child_process hook = CHILD_PROCESS_INIT;
	const char *p;

	p = find_hook(name);
	if (!p)
	return 0;

	strvec_push(&hook.args, p);
	while ((p = va_arg(args, const char *)))
	strvec_push(&hook.args, p);
	hook.env = env;
	hook.no_stdin = 1;
	hook.stdout_to_stderr = 1;
	hook.trace2_hook_name = name;

	return run_command(&hook);
	}

	int run_hook_le(const char const env, const char *name, ...)
	{
	va_list args;
	int ret;

	va_start(args, name);
	ret = run_hook_ve(env, name, args);
	va_end(args);

	return ret;
	}

	struct io_pump {
	/* initialized by caller */
	int fd;
	int type; /* POLLOUT or POLLIN */
	union {
	struct {
	const char *buf;
	size_t len;
	} out;
	struct {
	struct strbuf *buf;
	size_t hint;
	} in;
	} u;

	/* returned by pump_io */
	int error; /* 0 for success, otherwise errno */

	/* internal use */
	struct pollfd *pfd;
	};

	static int pump_io_round(struct io_pump slots, int nr, struct pollfd pfd)
	{
	int pollsize = 0;
	int i;

	for (i = 0; i < nr; i++) {
	struct io_pump *io = &slots[i];
	if (io->fd < 0)
	continue;
	pfd[pollsize].fd = io->fd;
	pfd[pollsize].events = io->type;
	io->pfd = &pfd[pollsize++];
	}

	if (!pollsize)
	return 0;

	if (poll(pfd, pollsize, -1) < 0) {
	if (errno == EINTR)
	return 1;
	die_errno("poll failed");
	}

	for (i = 0; i < nr; i++) {
	struct io_pump *io = &slots[i];

	if (io->fd < 0)
	continue;

	if (!(io->pfd->revents & (POLLOUT\|POLLIN\|POLLHUP\|POLLERR\|POLLNVAL)))
	continue;

	if (io->type == POLLOUT) {
	ssize_t len = xwrite(io->fd,
	io->u.out.buf, io->u.out.len);
	if (len < 0) {
	io->error = errno;
	close(io->fd);
	io->fd = -1;
	} else {
	io->u.out.buf += len;
	io->u.out.len -= len;
	if (!io->u.out.len) {
	close(io->fd);
	io->fd = -1;
	}
	}
	}

	if (io->type == POLLIN) {
	ssize_t len = strbuf_read_once(io->u.in.buf,
	io->fd, io->u.in.hint);
	if (len < 0)
	io->error = errno;
	if (len <= 0) {
	close(io->fd);
	io->fd = -1;
	}
	}
	}

	return 1;
	}

	static int pump_io(struct io_pump *slots, int nr)
	{
	struct pollfd *pfd;
	int i;

	for (i = 0; i < nr; i++)
	slots[i].error = 0;

	ALLOC_ARRAY(pfd, nr);
	while (pump_io_round(slots, nr, pfd))
	; /* nothing */
	free(pfd);

	/* There may be multiple errno values, so just pick the first. */
	for (i = 0; i < nr; i++) {
	if (slots[i].error) {
	errno = slots[i].error;
	return -1;
	}
	}
	return 0;
	}


	int pipe_command(struct child_process *cmd,
	const char *in, size_t in_len,
	struct strbuf *out, size_t out_hint,
	struct strbuf *err, size_t err_hint)
	{
	struct io_pump io[3];
	int nr = 0;

	if (in)
	cmd->in = -1;
	if (out)
	cmd->out = -1;
	if (err)
	cmd->err = -1;

	if (start_command(cmd) < 0)
	return -1;

	if (in) {
	io[nr].fd = cmd->in;
	io[nr].type = POLLOUT;
	io[nr].u.out.buf = in;
	io[nr].u.out.len = in_len;
	nr++;
	}
	if (out) {
	io[nr].fd = cmd->out;
	io[nr].type = POLLIN;
	io[nr].u.in.buf = out;
	io[nr].u.in.hint = out_hint;
	nr++;
	}
	if (err) {
	io[nr].fd = cmd->err;
	io[nr].type = POLLIN;
	io[nr].u.in.buf = err;
	io[nr].u.in.hint = err_hint;
	nr++;
	}

	if (pump_io(io, nr) < 0) {
	finish_command(cmd); /* throw away exit code */
	return -1;
	}

	return finish_command(cmd);
	}

	enum child_state {
	GIT_CP_FREE,
	GIT_CP_WORKING,
	GIT_CP_WAIT_CLEANUP,
	};

	struct parallel_processes {
	void *data;

	int max_processes;
	int nr_processes;

	get_next_task_fn get_next_task;
	start_failure_fn start_failure;
	task_finished_fn task_finished;

	struct {
	enum child_state state;
	struct child_process process;
	struct strbuf err;
	void *data;
	} *children;
	/*
	* The struct pollfd is logically part of *children,
	* but the system call expects it as its own array.
	*/
	struct pollfd *pfd;

	unsigned shutdown : 1;

	int output_owner;
	struct strbuf buffered_output; /* of finished children */
	};

	static int default_start_failure(struct strbuf *out,
	void *pp_cb,
	void *pp_task_cb)
	{
	return 0;
	}

	static int default_task_finished(int result,
	struct strbuf *out,
	void *pp_cb,
	void *pp_task_cb)
	{
	return 0;
	}

	static void kill_children(struct parallel_processes *pp, int signo)
	{
	int i, n = pp->max_processes;

	for (i = 0; i < n; i++)
	if (pp->children[i].state == GIT_CP_WORKING)
	kill(pp->children[i].process.pid, signo);
	}

	static struct parallel_processes *pp_for_signal;

	static void handle_children_on_signal(int signo)
	{
	kill_children(pp_for_signal, signo);
	sigchain_pop(signo);
	raise(signo);
	}

	static void pp_init(struct parallel_processes *pp,
	int n,
	get_next_task_fn get_next_task,
	start_failure_fn start_failure,
	task_finished_fn task_finished,
	void *data)
	{
	int i;

	if (n < 1)
	n = online_cpus();

	pp->max_processes = n;

	trace_printf("run_processes_parallel: preparing to run up to %d tasks", n);

	pp->data = data;
	if (!get_next_task)
	BUG("you need to specify a get_next_task function");
	pp->get_next_task = get_next_task;

	pp->start_failure = start_failure ? start_failure : default_start_failure;
	pp->task_finished = task_finished ? task_finished : default_task_finished;

	pp->nr_processes = 0;
	pp->output_owner = 0;
	pp->shutdown = 0;
	CALLOC_ARRAY(pp->children, n);
	CALLOC_ARRAY(pp->pfd, n);
	strbuf_init(&pp->buffered_output, 0);

	for (i = 0; i < n; i++) {
	strbuf_init(&pp->children[i].err, 0);
	child_process_init(&pp->children[i].process);
	pp->pfd[i].events = POLLIN \| POLLHUP;
	pp->pfd[i].fd = -1;
	}

	pp_for_signal = pp;
	sigchain_push_common(handle_children_on_signal);
	}

	static void pp_cleanup(struct parallel_processes *pp)
	{
	int i;

	trace_printf("run_processes_parallel: done");
	for (i = 0; i < pp->max_processes; i++) {
	strbuf_release(&pp->children[i].err);
	child_process_clear(&pp->children[i].process);
	}

	free(pp->children);
	free(pp->pfd);

	/*
	* When get_next_task added messages to the buffer in its last
	* iteration, the buffered output is non empty.
	*/
	strbuf_write(&pp->buffered_output, stderr);
	strbuf_release(&pp->buffered_output);

	sigchain_pop_common();
	}

	/* returns
	* 0 if a new task was started.
	* 1 if no new jobs was started (get_next_task ran out of work, non critical
	* problem with starting a new command)
	* <0 no new job was started, user wishes to shutdown early. Use negative code
	* to signal the children.
	*/
	static int pp_start_one(struct parallel_processes *pp)
	{
	int i, code;

	for (i = 0; i < pp->max_processes; i++)
	if (pp->children[i].state == GIT_CP_FREE)
	break;
	if (i == pp->max_processes)
	BUG("bookkeeping is hard");

	code = pp->get_next_task(&pp->children[i].process,
	&pp->children[i].err,
	pp->data,
	&pp->children[i].data);
	if (!code) {
	strbuf_addbuf(&pp->buffered_output, &pp->children[i].err);
	strbuf_reset(&pp->children[i].err);
	return 1;
	}
	pp->children[i].process.err = -1;
	pp->children[i].process.stdout_to_stderr = 1;
	pp->children[i].process.no_stdin = 1;

	if (start_command(&pp->children[i].process)) {
	code = pp->start_failure(&pp->children[i].err,
	pp->data,
	pp->children[i].data);
	strbuf_addbuf(&pp->buffered_output, &pp->children[i].err);
	strbuf_reset(&pp->children[i].err);
	if (code)
	pp->shutdown = 1;
	return code;
	}

	pp->nr_processes++;
	pp->children[i].state = GIT_CP_WORKING;
	pp->pfd[i].fd = pp->children[i].process.err;
	return 0;
	}

	static void pp_buffer_stderr(struct parallel_processes *pp, int output_timeout)
	{
	int i;

	while ((i = poll(pp->pfd, pp->max_processes, output_timeout)) < 0) {
	if (errno == EINTR)
	continue;
	pp_cleanup(pp);
	die_errno("poll");
	}

	/* Buffer output from all pipes. */
	for (i = 0; i < pp->max_processes; i++) {
	if (pp->children[i].state == GIT_CP_WORKING &&
	pp->pfd[i].revents & (POLLIN \| POLLHUP)) {
	int n = strbuf_read_once(&pp->children[i].err,
	pp->children[i].process.err, 0);
	if (n == 0) {
	close(pp->children[i].process.err);
	pp->children[i].state = GIT_CP_WAIT_CLEANUP;
	} else if (n < 0)
	if (errno != EAGAIN)
	die_errno("read");
	}
	}
	}

	static void pp_output(struct parallel_processes *pp)
	{
	int i = pp->output_owner;
	if (pp->children[i].state == GIT_CP_WORKING &&
	pp->children[i].err.len) {
	strbuf_write(&pp->children[i].err, stderr);
	strbuf_reset(&pp->children[i].err);
	}
	}

	static int pp_collect_finished(struct parallel_processes *pp)
	{
	int i, code;
	int n = pp->max_processes;
	int result = 0;

	while (pp->nr_processes > 0) {
	for (i = 0; i < pp->max_processes; i++)
	if (pp->children[i].state == GIT_CP_WAIT_CLEANUP)
	break;
	if (i == pp->max_processes)
	break;

	code = finish_command(&pp->children[i].process);

	code = pp->task_finished(code,
	&pp->children[i].err, pp->data,
	pp->children[i].data);

	if (code)
	result = code;
	if (code < 0)
	break;

	pp->nr_processes--;
	pp->children[i].state = GIT_CP_FREE;
	pp->pfd[i].fd = -1;
	child_process_init(&pp->children[i].process);

	if (i != pp->output_owner) {
	strbuf_addbuf(&pp->buffered_output, &pp->children[i].err);
	strbuf_reset(&pp->children[i].err);
	} else {
	strbuf_write(&pp->children[i].err, stderr);
	strbuf_reset(&pp->children[i].err);

	/* Output all other finished child processes */
	strbuf_write(&pp->buffered_output, stderr);
	strbuf_reset(&pp->buffered_output);

	/*
	* Pick next process to output live.
	* NEEDSWORK:
	* For now we pick it randomly by doing a round
	* robin. Later we may want to pick the one with
	* the most output or the longest or shortest
	* running process time.
	*/
	for (i = 0; i < n; i++)
	if (pp->children[(pp->output_owner + i) % n].state == GIT_CP_WORKING)
	break;
	pp->output_owner = (pp->output_owner + i) % n;
	}
	}
	return result;
	}

	int run_processes_parallel(int n,
	get_next_task_fn get_next_task,
	start_failure_fn start_failure,
	task_finished_fn task_finished,
	void *pp_cb)
	{
	int i, code;
	int output_timeout = 100;
	int spawn_cap = 4;
	struct parallel_processes pp;

	pp_init(&pp, n, get_next_task, start_failure, task_finished, pp_cb);
	while (1) {
	for (i = 0;
	i < spawn_cap && !pp.shutdown &&
	pp.nr_processes < pp.max_processes;
	i++) {
	code = pp_start_one(&pp);
	if (!code)
	continue;
	if (code < 0) {
	pp.shutdown = 1;
	kill_children(&pp, -code);
	}
	break;
	}
	if (!pp.nr_processes)
	break;
	pp_buffer_stderr(&pp, output_timeout);
	pp_output(&pp);
	code = pp_collect_finished(&pp);
	if (code) {
	pp.shutdown = 1;
	if (code < 0)
	kill_children(&pp, -code);
	}
	}

	pp_cleanup(&pp);
	return 0;
	}

	int run_processes_parallel_tr2(int n, get_next_task_fn get_next_task,
	start_failure_fn start_failure,
	task_finished_fn task_finished, void *pp_cb,
	const char tr2_category, const char tr2_label)
	{
	int result;

	trace2_region_enter_printf(tr2_category, tr2_label, NULL, "max:%d",
	((n < 1) ? online_cpus() : n));

	result = run_processes_parallel(n, get_next_task, start_failure,
	task_finished, pp_cb);

	trace2_region_leave(tr2_category, tr2_label, NULL);

	return result;
	}

	int run_auto_maintenance(int quiet)
	{
	int enabled;
	struct child_process maint = CHILD_PROCESS_INIT;

	if (!git_config_get_bool("maintenance.auto", &enabled) &&
	!enabled)
	return 0;

	maint.git_cmd = 1;
	strvec_pushl(&maint.args, "maintenance", "run", "--auto", NULL);
	strvec_push(&maint.args, quiet ? "--quiet" : "--no-quiet");

	return run_command(&maint);
	}

	void prepare_other_repo_env(struct strvec env_array, const char new_git_dir)
	{
	const char * const *var;

	for (var = local_repo_env; *var; var++) {
	if (strcmp(*var, CONFIG_DATA_ENVIRONMENT) &&
	strcmp(*var, CONFIG_COUNT_ENVIRONMENT))
	strvec_push(env_array, *var);
	}
	strvec_pushf(env_array, "%s=%s", GIT_DIR_ENVIRONMENT, new_git_dir);
	}

Jul	AUG	Apr
	17
2017	2021	2023

git / git

git/run-command.c