2 #include "run-command.h"
5 #include "argv-array.h"
6 #include "thread-utils.h"
8 #include "string-list.h"
11 void child_process_init(struct child_process
*child
)
13 memset(child
, 0, sizeof(*child
));
14 argv_array_init(&child
->args
);
15 argv_array_init(&child
->env_array
);
18 void child_process_clear(struct child_process
*child
)
20 argv_array_clear(&child
->args
);
21 argv_array_clear(&child
->env_array
);
24 struct child_to_clean
{
26 struct child_process
*process
;
27 struct child_to_clean
*next
;
29 static struct child_to_clean
*children_to_clean
;
30 static int installed_child_cleanup_handler
;
32 static void cleanup_children(int sig
, int in_signal
)
34 struct child_to_clean
*children_to_wait_for
= NULL
;
36 while (children_to_clean
) {
37 struct child_to_clean
*p
= children_to_clean
;
38 children_to_clean
= p
->next
;
40 if (p
->process
&& !in_signal
) {
41 struct child_process
*process
= p
->process
;
42 if (process
->clean_on_exit_handler
) {
44 "trace: run_command: running exit handler for pid %"
45 PRIuMAX
, (uintmax_t)p
->pid
47 process
->clean_on_exit_handler(process
);
53 if (p
->process
&& p
->process
->wait_after_clean
) {
54 p
->next
= children_to_wait_for
;
55 children_to_wait_for
= p
;
62 while (children_to_wait_for
) {
63 struct child_to_clean
*p
= children_to_wait_for
;
64 children_to_wait_for
= p
->next
;
66 while (waitpid(p
->pid
, NULL
, 0) < 0 && errno
== EINTR
)
67 ; /* spin waiting for process exit or error */
74 static void cleanup_children_on_signal(int sig
)
76 cleanup_children(sig
, 1);
81 static void cleanup_children_on_exit(void)
83 cleanup_children(SIGTERM
, 0);
86 static void mark_child_for_cleanup(pid_t pid
, struct child_process
*process
)
88 struct child_to_clean
*p
= xmalloc(sizeof(*p
));
91 p
->next
= children_to_clean
;
92 children_to_clean
= p
;
94 if (!installed_child_cleanup_handler
) {
95 atexit(cleanup_children_on_exit
);
96 sigchain_push_common(cleanup_children_on_signal
);
97 installed_child_cleanup_handler
= 1;
101 static void clear_child_for_cleanup(pid_t pid
)
103 struct child_to_clean
**pp
;
105 for (pp
= &children_to_clean
; *pp
; pp
= &(*pp
)->next
) {
106 struct child_to_clean
*clean_me
= *pp
;
108 if (clean_me
->pid
== pid
) {
109 *pp
= clean_me
->next
;
116 static inline void close_pair(int fd
[2])
122 int is_executable(const char *name
)
126 if (stat(name
, &st
) || /* stat, not lstat */
127 !S_ISREG(st
.st_mode
))
130 #if defined(GIT_WINDOWS_NATIVE)
132 * On Windows there is no executable bit. The file extension
133 * indicates whether it can be run as an executable, and Git
134 * has special-handling to detect scripts and launch them
135 * through the indicated script interpreter. We test for the
136 * file extension first because virus scanners may make
137 * it quite expensive to open many files.
139 if (ends_with(name
, ".exe"))
144 * Now that we know it does not have an executable extension,
145 * peek into the file instead.
149 int fd
= open(name
, O_RDONLY
);
150 st
.st_mode
&= ~S_IXUSR
;
152 n
= read(fd
, buf
, 2);
154 /* look for a she-bang */
155 if (!strcmp(buf
, "#!"))
156 st
.st_mode
|= S_IXUSR
;
161 return st
.st_mode
& S_IXUSR
;
165 * Search $PATH for a command. This emulates the path search that
166 * execvp would perform, without actually executing the command so it
167 * can be used before fork() to prepare to run a command using
168 * execve() or after execvp() to diagnose why it failed.
170 * The caller should ensure that file contains no directory
173 * Returns the path to the command, as found in $PATH or NULL if the
174 * command could not be found. The caller inherits ownership of the memory
175 * used to store the resultant path.
177 * This should not be used on Windows, where the $PATH search rules
178 * are more complicated (e.g., a search for "foo" should find
181 static char *locate_in_PATH(const char *file
)
183 const char *p
= getenv("PATH");
184 struct strbuf buf
= STRBUF_INIT
;
190 const char *end
= strchrnul(p
, ':');
194 /* POSIX specifies an empty entry as the current directory. */
196 strbuf_add(&buf
, p
, end
- p
);
197 strbuf_addch(&buf
, '/');
199 strbuf_addstr(&buf
, file
);
201 if (is_executable(buf
.buf
))
202 return strbuf_detach(&buf
, NULL
);
209 strbuf_release(&buf
);
213 static int exists_in_PATH(const char *file
)
215 char *r
= locate_in_PATH(file
);
220 int sane_execvp(const char *file
, char * const argv
[])
222 if (!execvp(file
, argv
))
223 return 0; /* cannot happen ;-) */
226 * When a command can't be found because one of the directories
227 * listed in $PATH is unsearchable, execvp reports EACCES, but
228 * careful usability testing (read: analysis of occasional bug
229 * reports) reveals that "No such file or directory" is more
232 * We avoid commands with "/", because execvp will not do $PATH
233 * lookups in that case.
235 * The reassignment of EACCES to errno looks like a no-op below,
236 * but we need to protect against exists_in_PATH overwriting errno.
238 if (errno
== EACCES
&& !strchr(file
, '/'))
239 errno
= exists_in_PATH(file
) ? EACCES
: ENOENT
;
240 else if (errno
== ENOTDIR
&& !strchr(file
, '/'))
245 static const char **prepare_shell_cmd(struct argv_array
*out
, const char **argv
)
248 die("BUG: shell command is empty");
250 if (strcspn(argv
[0], "|&;<>()$`\\\"' \t\n*?[#~=%") != strlen(argv
[0])) {
251 #ifndef GIT_WINDOWS_NATIVE
252 argv_array_push(out
, SHELL_PATH
);
254 argv_array_push(out
, "sh");
256 argv_array_push(out
, "-c");
259 * If we have no extra arguments, we do not even need to
260 * bother with the "$@" magic.
263 argv_array_push(out
, argv
[0]);
265 argv_array_pushf(out
, "%s \"$@\"", argv
[0]);
268 argv_array_pushv(out
, argv
);
272 #ifndef GIT_WINDOWS_NATIVE
273 static int child_notifier
= -1;
279 CHILD_ERR_SIGPROCMASK
,
286 enum child_errcode err
;
287 int syserr
; /* errno */
290 static void child_die(enum child_errcode err
)
292 struct child_err buf
;
297 /* write(2) on buf smaller than PIPE_BUF (min 512) is atomic: */
298 xwrite(child_notifier
, &buf
, sizeof(buf
));
302 static void child_dup2(int fd
, int to
)
304 if (dup2(fd
, to
) < 0)
305 child_die(CHILD_ERR_DUP2
);
308 static void child_close(int fd
)
311 child_die(CHILD_ERR_CLOSE
);
314 static void child_close_pair(int fd
[2])
321 * parent will make it look like the child spewed a fatal error and died
322 * this is needed to prevent changes to t0061.
324 static void fake_fatal(const char *err
, va_list params
)
326 vreportf("fatal: ", err
, params
);
329 static void child_error_fn(const char *err
, va_list params
)
331 const char msg
[] = "error() should not be called in child\n";
332 xwrite(2, msg
, sizeof(msg
) - 1);
335 static void child_warn_fn(const char *err
, va_list params
)
337 const char msg
[] = "warn() should not be called in child\n";
338 xwrite(2, msg
, sizeof(msg
) - 1);
341 static void NORETURN
child_die_fn(const char *err
, va_list params
)
343 const char msg
[] = "die() should not be called in child\n";
344 xwrite(2, msg
, sizeof(msg
) - 1);
348 /* this runs in the parent process */
349 static void child_err_spew(struct child_process
*cmd
, struct child_err
*cerr
)
351 static void (*old_errfn
)(const char *err
, va_list params
);
353 old_errfn
= get_error_routine();
354 set_error_routine(fake_fatal
);
355 errno
= cerr
->syserr
;
358 case CHILD_ERR_CHDIR
:
359 error_errno("exec '%s': cd to '%s' failed",
360 cmd
->argv
[0], cmd
->dir
);
363 error_errno("dup2() in child failed");
365 case CHILD_ERR_CLOSE
:
366 error_errno("close() in child failed");
368 case CHILD_ERR_SIGPROCMASK
:
369 error_errno("sigprocmask failed restoring signals");
371 case CHILD_ERR_ENOENT
:
372 error_errno("cannot run %s", cmd
->argv
[0]);
374 case CHILD_ERR_SILENT
:
376 case CHILD_ERR_ERRNO
:
377 error_errno("cannot exec '%s'", cmd
->argv
[0]);
380 set_error_routine(old_errfn
);
383 static void prepare_cmd(struct argv_array
*out
, const struct child_process
*cmd
)
386 die("BUG: command is empty");
389 * Add SHELL_PATH so in the event exec fails with ENOEXEC we can
390 * attempt to interpret the command with 'sh'.
392 argv_array_push(out
, SHELL_PATH
);
395 argv_array_push(out
, "git");
396 argv_array_pushv(out
, cmd
->argv
);
397 } else if (cmd
->use_shell
) {
398 prepare_shell_cmd(out
, cmd
->argv
);
400 argv_array_pushv(out
, cmd
->argv
);
404 * If there are no '/' characters in the command then perform a path
405 * lookup and use the resolved path as the command to exec. If there
406 * are no '/' characters or if the command wasn't found in the path,
407 * have exec attempt to invoke the command directly.
409 if (!strchr(out
->argv
[1], '/')) {
410 char *program
= locate_in_PATH(out
->argv
[1]);
412 free((char *)out
->argv
[1]);
413 out
->argv
[1] = program
;
418 static char **prep_childenv(const char *const *deltaenv
)
420 extern char **environ
;
422 struct string_list env
= STRING_LIST_INIT_DUP
;
423 struct strbuf key
= STRBUF_INIT
;
424 const char *const *p
;
427 /* Construct a sorted string list consisting of the current environ */
428 for (p
= (const char *const *) environ
; p
&& *p
; p
++) {
429 const char *equals
= strchr(*p
, '=');
433 strbuf_add(&key
, *p
, equals
- *p
);
434 string_list_append(&env
, key
.buf
)->util
= (void *) *p
;
436 string_list_append(&env
, *p
)->util
= (void *) *p
;
439 string_list_sort(&env
);
441 /* Merge in 'deltaenv' with the current environ */
442 for (p
= deltaenv
; p
&& *p
; p
++) {
443 const char *equals
= strchr(*p
, '=');
446 /* ('key=value'), insert or replace entry */
448 strbuf_add(&key
, *p
, equals
- *p
);
449 string_list_insert(&env
, key
.buf
)->util
= (void *) *p
;
451 /* otherwise ('key') remove existing entry */
452 string_list_remove(&env
, *p
, 0);
456 /* Create an array of 'char *' to be used as the childenv */
457 ALLOC_ARRAY(childenv
, env
.nr
+ 1);
458 for (i
= 0; i
< env
.nr
; i
++)
459 childenv
[i
] = env
.items
[i
].util
;
460 childenv
[env
.nr
] = NULL
;
462 string_list_clear(&env
, 0);
463 strbuf_release(&key
);
467 struct atfork_state
{
475 static void bug_die(int err
, const char *msg
)
479 die_errno("BUG: %s", msg
);
484 static void atfork_prepare(struct atfork_state
*as
)
488 if (sigfillset(&all
))
489 die_errno("sigfillset");
491 if (sigprocmask(SIG_SETMASK
, &all
, &as
->old
))
492 die_errno("sigprocmask");
494 bug_die(pthread_sigmask(SIG_SETMASK
, &all
, &as
->old
),
495 "blocking all signals");
496 bug_die(pthread_setcancelstate(PTHREAD_CANCEL_DISABLE
, &as
->cs
),
497 "disabling cancellation");
501 static void atfork_parent(struct atfork_state
*as
)
504 if (sigprocmask(SIG_SETMASK
, &as
->old
, NULL
))
505 die_errno("sigprocmask");
507 bug_die(pthread_setcancelstate(as
->cs
, NULL
),
508 "re-enabling cancellation");
509 bug_die(pthread_sigmask(SIG_SETMASK
, &as
->old
, NULL
),
510 "restoring signal mask");
513 #endif /* GIT_WINDOWS_NATIVE */
515 static inline void set_cloexec(int fd
)
517 int flags
= fcntl(fd
, F_GETFD
);
519 fcntl(fd
, F_SETFD
, flags
| FD_CLOEXEC
);
522 static int wait_or_whine(pid_t pid
, const char *argv0
, int in_signal
)
524 int status
, code
= -1;
526 int failed_errno
= 0;
528 while ((waiting
= waitpid(pid
, &status
, 0)) < 0 && errno
== EINTR
)
534 failed_errno
= errno
;
535 error_errno("waitpid for %s failed", argv0
);
536 } else if (waiting
!= pid
) {
537 error("waitpid is confused (%s)", argv0
);
538 } else if (WIFSIGNALED(status
)) {
539 code
= WTERMSIG(status
);
540 if (code
!= SIGINT
&& code
!= SIGQUIT
&& code
!= SIGPIPE
)
541 error("%s died of signal %d", argv0
, code
);
543 * This return value is chosen so that code & 0xff
544 * mimics the exit code that a POSIX shell would report for
545 * a program that died from this signal.
548 } else if (WIFEXITED(status
)) {
549 code
= WEXITSTATUS(status
);
551 error("waitpid is confused (%s)", argv0
);
554 clear_child_for_cleanup(pid
);
556 errno
= failed_errno
;
560 static void trace_add_env(struct strbuf
*dst
, const char *const *deltaenv
)
562 struct string_list envs
= STRING_LIST_INIT_DUP
;
563 const char *const *e
;
565 int printed_unset
= 0;
567 /* Last one wins, see run-command.c:prep_childenv() for context */
568 for (e
= deltaenv
; e
&& *e
; e
++) {
569 struct strbuf key
= STRBUF_INIT
;
570 char *equals
= strchr(*e
, '=');
573 strbuf_add(&key
, *e
, equals
- *e
);
574 string_list_insert(&envs
, key
.buf
)->util
= equals
+ 1;
576 string_list_insert(&envs
, *e
)->util
= NULL
;
578 strbuf_release(&key
);
581 /* "unset X Y...;" */
582 for (i
= 0; i
< envs
.nr
; i
++) {
583 const char *var
= envs
.items
[i
].string
;
584 const char *val
= envs
.items
[i
].util
;
586 if (val
|| !getenv(var
))
589 if (!printed_unset
) {
590 strbuf_addstr(dst
, " unset");
593 strbuf_addf(dst
, " %s", var
);
596 strbuf_addch(dst
, ';');
598 /* ... followed by "A=B C=D ..." */
599 for (i
= 0; i
< envs
.nr
; i
++) {
600 const char *var
= envs
.items
[i
].string
;
601 const char *val
= envs
.items
[i
].util
;
607 oldval
= getenv(var
);
608 if (oldval
&& !strcmp(val
, oldval
))
611 strbuf_addf(dst
, " %s=", var
);
612 sq_quote_buf_pretty(dst
, val
);
614 string_list_clear(&envs
, 0);
617 static void trace_run_command(const struct child_process
*cp
)
619 struct strbuf buf
= STRBUF_INIT
;
621 if (!trace_want(&trace_default_key
))
624 strbuf_addf(&buf
, "trace: run_command:");
626 * The caller is responsible for initializing cp->env from
627 * cp->env_array if needed. We only check one place.
630 trace_add_env(&buf
, cp
->env
);
632 strbuf_addstr(&buf
, " git");
633 sq_quote_argv_pretty(&buf
, cp
->argv
);
635 trace_printf("%s", buf
.buf
);
636 strbuf_release(&buf
);
639 int start_command(struct child_process
*cmd
)
641 int need_in
, need_out
, need_err
;
642 int fdin
[2], fdout
[2], fderr
[2];
647 cmd
->argv
= cmd
->args
.argv
;
649 cmd
->env
= cmd
->env_array
.argv
;
652 * In case of errors we must keep the promise to close FDs
653 * that have been passed in via ->in and ->out.
656 need_in
= !cmd
->no_stdin
&& cmd
->in
< 0;
658 if (pipe(fdin
) < 0) {
659 failed_errno
= errno
;
662 str
= "standard input";
668 need_out
= !cmd
->no_stdout
669 && !cmd
->stdout_to_stderr
672 if (pipe(fdout
) < 0) {
673 failed_errno
= errno
;
678 str
= "standard output";
684 need_err
= !cmd
->no_stderr
&& cmd
->err
< 0;
686 if (pipe(fderr
) < 0) {
687 failed_errno
= errno
;
696 str
= "standard error";
698 error("cannot create %s pipe for %s: %s",
699 str
, cmd
->argv
[0], strerror(failed_errno
));
700 child_process_clear(cmd
);
701 errno
= failed_errno
;
707 trace_run_command(cmd
);
711 #ifndef GIT_WINDOWS_NATIVE
716 struct argv_array argv
= ARGV_ARRAY_INIT
;
717 struct child_err cerr
;
718 struct atfork_state as
;
720 if (pipe(notify_pipe
))
721 notify_pipe
[0] = notify_pipe
[1] = -1;
723 if (cmd
->no_stdin
|| cmd
->no_stdout
|| cmd
->no_stderr
) {
724 null_fd
= open("/dev/null", O_RDWR
| O_CLOEXEC
);
726 die_errno(_("open /dev/null failed"));
727 set_cloexec(null_fd
);
730 prepare_cmd(&argv
, cmd
);
731 childenv
= prep_childenv(cmd
->env
);
735 * NOTE: In order to prevent deadlocking when using threads special
736 * care should be taken with the function calls made in between the
737 * fork() and exec() calls. No calls should be made to functions which
738 * require acquiring a lock (e.g. malloc) as the lock could have been
739 * held by another thread at the time of forking, causing the lock to
740 * never be released in the child process. This means only
741 * Async-Signal-Safe functions are permitted in the child.
744 failed_errno
= errno
;
748 * Ensure the default die/error/warn routines do not get
749 * called, they can take stdio locks and malloc.
751 set_die_routine(child_die_fn
);
752 set_error_routine(child_error_fn
);
753 set_warn_routine(child_warn_fn
);
755 close(notify_pipe
[0]);
756 set_cloexec(notify_pipe
[1]);
757 child_notifier
= notify_pipe
[1];
760 child_dup2(null_fd
, 0);
762 child_dup2(fdin
[0], 0);
763 child_close_pair(fdin
);
764 } else if (cmd
->in
) {
765 child_dup2(cmd
->in
, 0);
766 child_close(cmd
->in
);
770 child_dup2(null_fd
, 2);
772 child_dup2(fderr
[1], 2);
773 child_close_pair(fderr
);
774 } else if (cmd
->err
> 1) {
775 child_dup2(cmd
->err
, 2);
776 child_close(cmd
->err
);
780 child_dup2(null_fd
, 1);
781 else if (cmd
->stdout_to_stderr
)
784 child_dup2(fdout
[1], 1);
785 child_close_pair(fdout
);
786 } else if (cmd
->out
> 1) {
787 child_dup2(cmd
->out
, 1);
788 child_close(cmd
->out
);
791 if (cmd
->dir
&& chdir(cmd
->dir
))
792 child_die(CHILD_ERR_CHDIR
);
795 * restore default signal handlers here, in case
796 * we catch a signal right before execve below
798 for (sig
= 1; sig
< NSIG
; sig
++) {
799 /* ignored signals get reset to SIG_DFL on execve */
800 if (signal(sig
, SIG_DFL
) == SIG_IGN
)
801 signal(sig
, SIG_IGN
);
804 if (sigprocmask(SIG_SETMASK
, &as
.old
, NULL
) != 0)
805 child_die(CHILD_ERR_SIGPROCMASK
);
808 * Attempt to exec using the command and arguments starting at
809 * argv.argv[1]. argv.argv[0] contains SHELL_PATH which will
810 * be used in the event exec failed with ENOEXEC at which point
811 * we will try to interpret the command using 'sh'.
813 execve(argv
.argv
[1], (char *const *) argv
.argv
+ 1,
814 (char *const *) childenv
);
815 if (errno
== ENOEXEC
)
816 execve(argv
.argv
[0], (char *const *) argv
.argv
,
817 (char *const *) childenv
);
819 if (errno
== ENOENT
) {
820 if (cmd
->silent_exec_failure
)
821 child_die(CHILD_ERR_SILENT
);
822 child_die(CHILD_ERR_ENOENT
);
824 child_die(CHILD_ERR_ERRNO
);
829 error_errno("cannot fork() for %s", cmd
->argv
[0]);
830 else if (cmd
->clean_on_exit
)
831 mark_child_for_cleanup(cmd
->pid
, cmd
);
834 * Wait for child's exec. If the exec succeeds (or if fork()
835 * failed), EOF is seen immediately by the parent. Otherwise, the
836 * child process sends a child_err struct.
837 * Note that use of this infrastructure is completely advisory,
838 * therefore, we keep error checks minimal.
840 close(notify_pipe
[1]);
841 if (xread(notify_pipe
[0], &cerr
, sizeof(cerr
)) == sizeof(cerr
)) {
843 * At this point we know that fork() succeeded, but exec()
844 * failed. Errors have been reported to our stderr.
846 wait_or_whine(cmd
->pid
, cmd
->argv
[0], 0);
847 child_err_spew(cmd
, &cerr
);
848 failed_errno
= errno
;
851 close(notify_pipe
[0]);
855 argv_array_clear(&argv
);
860 int fhin
= 0, fhout
= 1, fherr
= 2;
861 const char **sargv
= cmd
->argv
;
862 struct argv_array nargv
= ARGV_ARRAY_INIT
;
865 fhin
= open("/dev/null", O_RDWR
);
872 fherr
= open("/dev/null", O_RDWR
);
874 fherr
= dup(fderr
[1]);
875 else if (cmd
->err
> 2)
876 fherr
= dup(cmd
->err
);
879 fhout
= open("/dev/null", O_RDWR
);
880 else if (cmd
->stdout_to_stderr
)
883 fhout
= dup(fdout
[1]);
884 else if (cmd
->out
> 1)
885 fhout
= dup(cmd
->out
);
888 cmd
->argv
= prepare_git_cmd(&nargv
, cmd
->argv
);
889 else if (cmd
->use_shell
)
890 cmd
->argv
= prepare_shell_cmd(&nargv
, cmd
->argv
);
892 cmd
->pid
= mingw_spawnvpe(cmd
->argv
[0], cmd
->argv
, (char**) cmd
->env
,
893 cmd
->dir
, fhin
, fhout
, fherr
);
894 failed_errno
= errno
;
895 if (cmd
->pid
< 0 && (!cmd
->silent_exec_failure
|| errno
!= ENOENT
))
896 error_errno("cannot spawn %s", cmd
->argv
[0]);
897 if (cmd
->clean_on_exit
&& cmd
->pid
>= 0)
898 mark_child_for_cleanup(cmd
->pid
, cmd
);
900 argv_array_clear(&nargv
);
924 child_process_clear(cmd
);
925 errno
= failed_errno
;
947 int finish_command(struct child_process
*cmd
)
949 int ret
= wait_or_whine(cmd
->pid
, cmd
->argv
[0], 0);
950 child_process_clear(cmd
);
954 int finish_command_in_signal(struct child_process
*cmd
)
956 return wait_or_whine(cmd
->pid
, cmd
->argv
[0], 1);
960 int run_command(struct child_process
*cmd
)
964 if (cmd
->out
< 0 || cmd
->err
< 0)
965 die("BUG: run_command with a pipe can cause deadlock");
967 code
= start_command(cmd
);
970 return finish_command(cmd
);
973 int run_command_v_opt(const char **argv
, int opt
)
975 return run_command_v_opt_cd_env(argv
, opt
, NULL
, NULL
);
978 int run_command_v_opt_cd_env(const char **argv
, int opt
, const char *dir
, const char *const *env
)
980 struct child_process cmd
= CHILD_PROCESS_INIT
;
982 cmd
.no_stdin
= opt
& RUN_COMMAND_NO_STDIN
? 1 : 0;
983 cmd
.git_cmd
= opt
& RUN_GIT_CMD
? 1 : 0;
984 cmd
.stdout_to_stderr
= opt
& RUN_COMMAND_STDOUT_TO_STDERR
? 1 : 0;
985 cmd
.silent_exec_failure
= opt
& RUN_SILENT_EXEC_FAILURE
? 1 : 0;
986 cmd
.use_shell
= opt
& RUN_USING_SHELL
? 1 : 0;
987 cmd
.clean_on_exit
= opt
& RUN_CLEAN_ON_EXIT
? 1 : 0;
990 return run_command(&cmd
);
994 static pthread_t main_thread
;
995 static int main_thread_set
;
996 static pthread_key_t async_key
;
997 static pthread_key_t async_die_counter
;
999 static void *run_thread(void *data
)
1001 struct async
*async
= data
;
1004 if (async
->isolate_sigpipe
) {
1007 sigaddset(&mask
, SIGPIPE
);
1008 if (pthread_sigmask(SIG_BLOCK
, &mask
, NULL
) < 0) {
1009 ret
= error("unable to block SIGPIPE in async thread");
1014 pthread_setspecific(async_key
, async
);
1015 ret
= async
->proc(async
->proc_in
, async
->proc_out
, async
->data
);
1019 static NORETURN
void die_async(const char *err
, va_list params
)
1021 vreportf("fatal: ", err
, params
);
1024 struct async
*async
= pthread_getspecific(async_key
);
1025 if (async
->proc_in
>= 0)
1026 close(async
->proc_in
);
1027 if (async
->proc_out
>= 0)
1028 close(async
->proc_out
);
1029 pthread_exit((void *)128);
1035 static int async_die_is_recursing(void)
1037 void *ret
= pthread_getspecific(async_die_counter
);
1038 pthread_setspecific(async_die_counter
, (void *)1);
1044 if (!main_thread_set
)
1045 return 0; /* no asyncs started yet */
1046 return !pthread_equal(main_thread
, pthread_self());
1049 static void NORETURN
async_exit(int code
)
1051 pthread_exit((void *)(intptr_t)code
);
1057 void (**handlers
)(void);
1062 static int git_atexit_installed
;
1064 static void git_atexit_dispatch(void)
1068 for (i
=git_atexit_hdlrs
.nr
; i
; i
--)
1069 git_atexit_hdlrs
.handlers
[i
-1]();
1072 static void git_atexit_clear(void)
1074 free(git_atexit_hdlrs
.handlers
);
1075 memset(&git_atexit_hdlrs
, 0, sizeof(git_atexit_hdlrs
));
1076 git_atexit_installed
= 0;
1080 int git_atexit(void (*handler
)(void))
1082 ALLOC_GROW(git_atexit_hdlrs
.handlers
, git_atexit_hdlrs
.nr
+ 1, git_atexit_hdlrs
.alloc
);
1083 git_atexit_hdlrs
.handlers
[git_atexit_hdlrs
.nr
++] = handler
;
1084 if (!git_atexit_installed
) {
1085 if (atexit(&git_atexit_dispatch
))
1087 git_atexit_installed
= 1;
1091 #define atexit git_atexit
1093 static int process_is_async
;
1096 return process_is_async
;
1099 static void NORETURN
async_exit(int code
)
1106 void check_pipe(int err
)
1112 signal(SIGPIPE
, SIG_DFL
);
1114 /* Should never happen, but just in case... */
1119 int start_async(struct async
*async
)
1121 int need_in
, need_out
;
1122 int fdin
[2], fdout
[2];
1123 int proc_in
, proc_out
;
1125 need_in
= async
->in
< 0;
1127 if (pipe(fdin
) < 0) {
1130 return error_errno("cannot create pipe");
1132 async
->in
= fdin
[1];
1135 need_out
= async
->out
< 0;
1137 if (pipe(fdout
) < 0) {
1142 return error_errno("cannot create pipe");
1144 async
->out
= fdout
[0];
1150 proc_in
= async
->in
;
1155 proc_out
= fdout
[1];
1156 else if (async
->out
)
1157 proc_out
= async
->out
;
1162 /* Flush stdio before fork() to avoid cloning buffers */
1165 async
->pid
= fork();
1166 if (async
->pid
< 0) {
1167 error_errno("fork (async) failed");
1176 process_is_async
= 1;
1177 exit(!!async
->proc(proc_in
, proc_out
, async
->data
));
1180 mark_child_for_cleanup(async
->pid
, NULL
);
1189 else if (async
->out
)
1192 if (!main_thread_set
) {
1194 * We assume that the first time that start_async is called
1195 * it is from the main thread.
1197 main_thread_set
= 1;
1198 main_thread
= pthread_self();
1199 pthread_key_create(&async_key
, NULL
);
1200 pthread_key_create(&async_die_counter
, NULL
);
1201 set_die_routine(die_async
);
1202 set_die_is_recursing_routine(async_die_is_recursing
);
1206 set_cloexec(proc_in
);
1208 set_cloexec(proc_out
);
1209 async
->proc_in
= proc_in
;
1210 async
->proc_out
= proc_out
;
1212 int err
= pthread_create(&async
->tid
, NULL
, run_thread
, async
);
1214 error_errno("cannot create thread");
1229 else if (async
->out
)
1234 int finish_async(struct async
*async
)
1237 return wait_or_whine(async
->pid
, "child process", 0);
1239 void *ret
= (void *)(intptr_t)(-1);
1241 if (pthread_join(async
->tid
, &ret
))
1242 error("pthread_join failed");
1243 return (int)(intptr_t)ret
;
1247 const char *find_hook(const char *name
)
1249 static struct strbuf path
= STRBUF_INIT
;
1251 strbuf_reset(&path
);
1252 strbuf_git_path(&path
, "hooks/%s", name
);
1253 if (access(path
.buf
, X_OK
) < 0) {
1256 #ifdef STRIP_EXTENSION
1257 strbuf_addstr(&path
, STRIP_EXTENSION
);
1258 if (access(path
.buf
, X_OK
) >= 0)
1260 if (errno
== EACCES
)
1264 if (err
== EACCES
&& advice_ignored_hook
) {
1265 static struct string_list advise_given
= STRING_LIST_INIT_DUP
;
1267 if (!string_list_lookup(&advise_given
, name
)) {
1268 string_list_insert(&advise_given
, name
);
1269 advise(_("The '%s' hook was ignored because "
1270 "it's not set as executable.\n"
1271 "You can disable this warning with "
1272 "`git config advice.ignoredHook false`."),
1281 int run_hook_ve(const char *const *env
, const char *name
, va_list args
)
1283 struct child_process hook
= CHILD_PROCESS_INIT
;
1286 p
= find_hook(name
);
1290 argv_array_push(&hook
.args
, p
);
1291 while ((p
= va_arg(args
, const char *)))
1292 argv_array_push(&hook
.args
, p
);
1295 hook
.stdout_to_stderr
= 1;
1297 return run_command(&hook
);
1300 int run_hook_le(const char *const *env
, const char *name
, ...)
1305 va_start(args
, name
);
1306 ret
= run_hook_ve(env
, name
, args
);
1313 /* initialized by caller */
1315 int type
; /* POLLOUT or POLLIN */
1327 /* returned by pump_io */
1328 int error
; /* 0 for success, otherwise errno */
1334 static int pump_io_round(struct io_pump
*slots
, int nr
, struct pollfd
*pfd
)
1339 for (i
= 0; i
< nr
; i
++) {
1340 struct io_pump
*io
= &slots
[i
];
1343 pfd
[pollsize
].fd
= io
->fd
;
1344 pfd
[pollsize
].events
= io
->type
;
1345 io
->pfd
= &pfd
[pollsize
++];
1351 if (poll(pfd
, pollsize
, -1) < 0) {
1354 die_errno("poll failed");
1357 for (i
= 0; i
< nr
; i
++) {
1358 struct io_pump
*io
= &slots
[i
];
1363 if (!(io
->pfd
->revents
& (POLLOUT
|POLLIN
|POLLHUP
|POLLERR
|POLLNVAL
)))
1366 if (io
->type
== POLLOUT
) {
1367 ssize_t len
= xwrite(io
->fd
,
1368 io
->u
.out
.buf
, io
->u
.out
.len
);
1374 io
->u
.out
.buf
+= len
;
1375 io
->u
.out
.len
-= len
;
1376 if (!io
->u
.out
.len
) {
1383 if (io
->type
== POLLIN
) {
1384 ssize_t len
= strbuf_read_once(io
->u
.in
.buf
,
1385 io
->fd
, io
->u
.in
.hint
);
1398 static int pump_io(struct io_pump
*slots
, int nr
)
1403 for (i
= 0; i
< nr
; i
++)
1406 ALLOC_ARRAY(pfd
, nr
);
1407 while (pump_io_round(slots
, nr
, pfd
))
1411 /* There may be multiple errno values, so just pick the first. */
1412 for (i
= 0; i
< nr
; i
++) {
1413 if (slots
[i
].error
) {
1414 errno
= slots
[i
].error
;
1422 int pipe_command(struct child_process
*cmd
,
1423 const char *in
, size_t in_len
,
1424 struct strbuf
*out
, size_t out_hint
,
1425 struct strbuf
*err
, size_t err_hint
)
1427 struct io_pump io
[3];
1437 if (start_command(cmd
) < 0)
1441 io
[nr
].fd
= cmd
->in
;
1442 io
[nr
].type
= POLLOUT
;
1443 io
[nr
].u
.out
.buf
= in
;
1444 io
[nr
].u
.out
.len
= in_len
;
1448 io
[nr
].fd
= cmd
->out
;
1449 io
[nr
].type
= POLLIN
;
1450 io
[nr
].u
.in
.buf
= out
;
1451 io
[nr
].u
.in
.hint
= out_hint
;
1455 io
[nr
].fd
= cmd
->err
;
1456 io
[nr
].type
= POLLIN
;
1457 io
[nr
].u
.in
.buf
= err
;
1458 io
[nr
].u
.in
.hint
= err_hint
;
1462 if (pump_io(io
, nr
) < 0) {
1463 finish_command(cmd
); /* throw away exit code */
1467 return finish_command(cmd
);
1473 GIT_CP_WAIT_CLEANUP
,
1476 struct parallel_processes
{
1482 get_next_task_fn get_next_task
;
1483 start_failure_fn start_failure
;
1484 task_finished_fn task_finished
;
1487 enum child_state state
;
1488 struct child_process process
;
1493 * The struct pollfd is logically part of *children,
1494 * but the system call expects it as its own array.
1498 unsigned shutdown
: 1;
1501 struct strbuf buffered_output
; /* of finished children */
1504 static int default_start_failure(struct strbuf
*out
,
1511 static int default_task_finished(int result
,
1519 static void kill_children(struct parallel_processes
*pp
, int signo
)
1521 int i
, n
= pp
->max_processes
;
1523 for (i
= 0; i
< n
; i
++)
1524 if (pp
->children
[i
].state
== GIT_CP_WORKING
)
1525 kill(pp
->children
[i
].process
.pid
, signo
);
1528 static struct parallel_processes
*pp_for_signal
;
1530 static void handle_children_on_signal(int signo
)
1532 kill_children(pp_for_signal
, signo
);
1533 sigchain_pop(signo
);
1537 static void pp_init(struct parallel_processes
*pp
,
1539 get_next_task_fn get_next_task
,
1540 start_failure_fn start_failure
,
1541 task_finished_fn task_finished
,
1549 pp
->max_processes
= n
;
1551 trace_printf("run_processes_parallel: preparing to run up to %d tasks", n
);
1555 die("BUG: you need to specify a get_next_task function");
1556 pp
->get_next_task
= get_next_task
;
1558 pp
->start_failure
= start_failure
? start_failure
: default_start_failure
;
1559 pp
->task_finished
= task_finished
? task_finished
: default_task_finished
;
1561 pp
->nr_processes
= 0;
1562 pp
->output_owner
= 0;
1564 pp
->children
= xcalloc(n
, sizeof(*pp
->children
));
1565 pp
->pfd
= xcalloc(n
, sizeof(*pp
->pfd
));
1566 strbuf_init(&pp
->buffered_output
, 0);
1568 for (i
= 0; i
< n
; i
++) {
1569 strbuf_init(&pp
->children
[i
].err
, 0);
1570 child_process_init(&pp
->children
[i
].process
);
1571 pp
->pfd
[i
].events
= POLLIN
| POLLHUP
;
1576 sigchain_push_common(handle_children_on_signal
);
1579 static void pp_cleanup(struct parallel_processes
*pp
)
1583 trace_printf("run_processes_parallel: done");
1584 for (i
= 0; i
< pp
->max_processes
; i
++) {
1585 strbuf_release(&pp
->children
[i
].err
);
1586 child_process_clear(&pp
->children
[i
].process
);
1593 * When get_next_task added messages to the buffer in its last
1594 * iteration, the buffered output is non empty.
1596 strbuf_write(&pp
->buffered_output
, stderr
);
1597 strbuf_release(&pp
->buffered_output
);
1599 sigchain_pop_common();
1603 * 0 if a new task was started.
1604 * 1 if no new jobs was started (get_next_task ran out of work, non critical
1605 * problem with starting a new command)
1606 * <0 no new job was started, user wishes to shutdown early. Use negative code
1607 * to signal the children.
1609 static int pp_start_one(struct parallel_processes
*pp
)
1613 for (i
= 0; i
< pp
->max_processes
; i
++)
1614 if (pp
->children
[i
].state
== GIT_CP_FREE
)
1616 if (i
== pp
->max_processes
)
1617 die("BUG: bookkeeping is hard");
1619 code
= pp
->get_next_task(&pp
->children
[i
].process
,
1620 &pp
->children
[i
].err
,
1622 &pp
->children
[i
].data
);
1624 strbuf_addbuf(&pp
->buffered_output
, &pp
->children
[i
].err
);
1625 strbuf_reset(&pp
->children
[i
].err
);
1628 pp
->children
[i
].process
.err
= -1;
1629 pp
->children
[i
].process
.stdout_to_stderr
= 1;
1630 pp
->children
[i
].process
.no_stdin
= 1;
1632 if (start_command(&pp
->children
[i
].process
)) {
1633 code
= pp
->start_failure(&pp
->children
[i
].err
,
1635 pp
->children
[i
].data
);
1636 strbuf_addbuf(&pp
->buffered_output
, &pp
->children
[i
].err
);
1637 strbuf_reset(&pp
->children
[i
].err
);
1644 pp
->children
[i
].state
= GIT_CP_WORKING
;
1645 pp
->pfd
[i
].fd
= pp
->children
[i
].process
.err
;
1649 static void pp_buffer_stderr(struct parallel_processes
*pp
, int output_timeout
)
1653 while ((i
= poll(pp
->pfd
, pp
->max_processes
, output_timeout
)) < 0) {
1660 /* Buffer output from all pipes. */
1661 for (i
= 0; i
< pp
->max_processes
; i
++) {
1662 if (pp
->children
[i
].state
== GIT_CP_WORKING
&&
1663 pp
->pfd
[i
].revents
& (POLLIN
| POLLHUP
)) {
1664 int n
= strbuf_read_once(&pp
->children
[i
].err
,
1665 pp
->children
[i
].process
.err
, 0);
1667 close(pp
->children
[i
].process
.err
);
1668 pp
->children
[i
].state
= GIT_CP_WAIT_CLEANUP
;
1670 if (errno
!= EAGAIN
)
1676 static void pp_output(struct parallel_processes
*pp
)
1678 int i
= pp
->output_owner
;
1679 if (pp
->children
[i
].state
== GIT_CP_WORKING
&&
1680 pp
->children
[i
].err
.len
) {
1681 strbuf_write(&pp
->children
[i
].err
, stderr
);
1682 strbuf_reset(&pp
->children
[i
].err
);
1686 static int pp_collect_finished(struct parallel_processes
*pp
)
1689 int n
= pp
->max_processes
;
1692 while (pp
->nr_processes
> 0) {
1693 for (i
= 0; i
< pp
->max_processes
; i
++)
1694 if (pp
->children
[i
].state
== GIT_CP_WAIT_CLEANUP
)
1696 if (i
== pp
->max_processes
)
1699 code
= finish_command(&pp
->children
[i
].process
);
1701 code
= pp
->task_finished(code
,
1702 &pp
->children
[i
].err
, pp
->data
,
1703 pp
->children
[i
].data
);
1711 pp
->children
[i
].state
= GIT_CP_FREE
;
1713 child_process_init(&pp
->children
[i
].process
);
1715 if (i
!= pp
->output_owner
) {
1716 strbuf_addbuf(&pp
->buffered_output
, &pp
->children
[i
].err
);
1717 strbuf_reset(&pp
->children
[i
].err
);
1719 strbuf_write(&pp
->children
[i
].err
, stderr
);
1720 strbuf_reset(&pp
->children
[i
].err
);
1722 /* Output all other finished child processes */
1723 strbuf_write(&pp
->buffered_output
, stderr
);
1724 strbuf_reset(&pp
->buffered_output
);
1727 * Pick next process to output live.
1729 * For now we pick it randomly by doing a round
1730 * robin. Later we may want to pick the one with
1731 * the most output or the longest or shortest
1732 * running process time.
1734 for (i
= 0; i
< n
; i
++)
1735 if (pp
->children
[(pp
->output_owner
+ i
) % n
].state
== GIT_CP_WORKING
)
1737 pp
->output_owner
= (pp
->output_owner
+ i
) % n
;
1743 int run_processes_parallel(int n
,
1744 get_next_task_fn get_next_task
,
1745 start_failure_fn start_failure
,
1746 task_finished_fn task_finished
,
1750 int output_timeout
= 100;
1752 struct parallel_processes pp
;
1754 pp_init(&pp
, n
, get_next_task
, start_failure
, task_finished
, pp_cb
);
1757 i
< spawn_cap
&& !pp
.shutdown
&&
1758 pp
.nr_processes
< pp
.max_processes
;
1760 code
= pp_start_one(&pp
);
1765 kill_children(&pp
, -code
);
1769 if (!pp
.nr_processes
)
1771 pp_buffer_stderr(&pp
, output_timeout
);
1773 code
= pp_collect_finished(&pp
);
1777 kill_children(&pp
, -code
);