2 #include "run-command.h"
6 #include "thread-utils.h"
8 #include "string-list.h"
14 void child_process_init(struct child_process
*child
)
16 struct child_process blank
= CHILD_PROCESS_INIT
;
17 memcpy(child
, &blank
, sizeof(*child
));
20 void child_process_clear(struct child_process
*child
)
22 strvec_clear(&child
->args
);
23 strvec_clear(&child
->env
);
26 struct child_to_clean
{
28 struct child_process
*process
;
29 struct child_to_clean
*next
;
31 static struct child_to_clean
*children_to_clean
;
32 static int installed_child_cleanup_handler
;
34 static void cleanup_children(int sig
, int in_signal
)
36 struct child_to_clean
*children_to_wait_for
= NULL
;
38 while (children_to_clean
) {
39 struct child_to_clean
*p
= children_to_clean
;
40 children_to_clean
= p
->next
;
42 if (p
->process
&& !in_signal
) {
43 struct child_process
*process
= p
->process
;
44 if (process
->clean_on_exit_handler
) {
46 "trace: run_command: running exit handler for pid %"
47 PRIuMAX
, (uintmax_t)p
->pid
49 process
->clean_on_exit_handler(process
);
55 if (p
->process
&& p
->process
->wait_after_clean
) {
56 p
->next
= children_to_wait_for
;
57 children_to_wait_for
= p
;
64 while (children_to_wait_for
) {
65 struct child_to_clean
*p
= children_to_wait_for
;
66 children_to_wait_for
= p
->next
;
68 while (waitpid(p
->pid
, NULL
, 0) < 0 && errno
== EINTR
)
69 ; /* spin waiting for process exit or error */
76 static void cleanup_children_on_signal(int sig
)
78 cleanup_children(sig
, 1);
83 static void cleanup_children_on_exit(void)
85 cleanup_children(SIGTERM
, 0);
88 static void mark_child_for_cleanup(pid_t pid
, struct child_process
*process
)
90 struct child_to_clean
*p
= xmalloc(sizeof(*p
));
93 p
->next
= children_to_clean
;
94 children_to_clean
= p
;
96 if (!installed_child_cleanup_handler
) {
97 atexit(cleanup_children_on_exit
);
98 sigchain_push_common(cleanup_children_on_signal
);
99 installed_child_cleanup_handler
= 1;
103 static void clear_child_for_cleanup(pid_t pid
)
105 struct child_to_clean
**pp
;
107 for (pp
= &children_to_clean
; *pp
; pp
= &(*pp
)->next
) {
108 struct child_to_clean
*clean_me
= *pp
;
110 if (clean_me
->pid
== pid
) {
111 *pp
= clean_me
->next
;
118 static inline void close_pair(int fd
[2])
124 int is_executable(const char *name
)
128 if (stat(name
, &st
) || /* stat, not lstat */
129 !S_ISREG(st
.st_mode
))
132 #if defined(GIT_WINDOWS_NATIVE)
134 * On Windows there is no executable bit. The file extension
135 * indicates whether it can be run as an executable, and Git
136 * has special-handling to detect scripts and launch them
137 * through the indicated script interpreter. We test for the
138 * file extension first because virus scanners may make
139 * it quite expensive to open many files.
141 if (ends_with(name
, ".exe"))
146 * Now that we know it does not have an executable extension,
147 * peek into the file instead.
151 int fd
= open(name
, O_RDONLY
);
152 st
.st_mode
&= ~S_IXUSR
;
154 n
= read(fd
, buf
, 2);
156 /* look for a she-bang */
157 if (!strcmp(buf
, "#!"))
158 st
.st_mode
|= S_IXUSR
;
163 return st
.st_mode
& S_IXUSR
;
167 * Search $PATH for a command. This emulates the path search that
168 * execvp would perform, without actually executing the command so it
169 * can be used before fork() to prepare to run a command using
170 * execve() or after execvp() to diagnose why it failed.
172 * The caller should ensure that file contains no directory
175 * Returns the path to the command, as found in $PATH or NULL if the
176 * command could not be found. The caller inherits ownership of the memory
177 * used to store the resultant path.
179 * This should not be used on Windows, where the $PATH search rules
180 * are more complicated (e.g., a search for "foo" should find
183 static char *locate_in_PATH(const char *file
)
185 const char *p
= getenv("PATH");
186 struct strbuf buf
= STRBUF_INIT
;
192 const char *end
= strchrnul(p
, ':');
196 /* POSIX specifies an empty entry as the current directory. */
198 strbuf_add(&buf
, p
, end
- p
);
199 strbuf_addch(&buf
, '/');
201 strbuf_addstr(&buf
, file
);
203 if (is_executable(buf
.buf
))
204 return strbuf_detach(&buf
, NULL
);
211 strbuf_release(&buf
);
215 int exists_in_PATH(const char *command
)
217 char *r
= locate_in_PATH(command
);
218 int found
= r
!= NULL
;
223 int sane_execvp(const char *file
, char * const argv
[])
225 #ifndef GIT_WINDOWS_NATIVE
227 * execvp() doesn't return, so we all we can do is tell trace2
228 * what we are about to do and let it leave a hint in the log
229 * (unless of course the execvp() fails).
231 * we skip this for Windows because the compat layer already
232 * has to emulate the execvp() call anyway.
234 int exec_id
= trace2_exec(file
, (const char **)argv
);
237 if (!execvp(file
, argv
))
238 return 0; /* cannot happen ;-) */
240 #ifndef GIT_WINDOWS_NATIVE
243 trace2_exec_result(exec_id
, ec
);
249 * When a command can't be found because one of the directories
250 * listed in $PATH is unsearchable, execvp reports EACCES, but
251 * careful usability testing (read: analysis of occasional bug
252 * reports) reveals that "No such file or directory" is more
255 * We avoid commands with "/", because execvp will not do $PATH
256 * lookups in that case.
258 * The reassignment of EACCES to errno looks like a no-op below,
259 * but we need to protect against exists_in_PATH overwriting errno.
261 if (errno
== EACCES
&& !strchr(file
, '/'))
262 errno
= exists_in_PATH(file
) ? EACCES
: ENOENT
;
263 else if (errno
== ENOTDIR
&& !strchr(file
, '/'))
268 static const char **prepare_shell_cmd(struct strvec
*out
, const char **argv
)
271 BUG("shell command is empty");
273 if (strcspn(argv
[0], "|&;<>()$`\\\"' \t\n*?[#~=%") != strlen(argv
[0])) {
274 #ifndef GIT_WINDOWS_NATIVE
275 strvec_push(out
, SHELL_PATH
);
277 strvec_push(out
, "sh");
279 strvec_push(out
, "-c");
282 * If we have no extra arguments, we do not even need to
283 * bother with the "$@" magic.
286 strvec_push(out
, argv
[0]);
288 strvec_pushf(out
, "%s \"$@\"", argv
[0]);
291 strvec_pushv(out
, argv
);
295 #ifndef GIT_WINDOWS_NATIVE
296 static int child_notifier
= -1;
302 CHILD_ERR_SIGPROCMASK
,
309 enum child_errcode err
;
310 int syserr
; /* errno */
313 static void child_die(enum child_errcode err
)
315 struct child_err buf
;
320 /* write(2) on buf smaller than PIPE_BUF (min 512) is atomic: */
321 xwrite(child_notifier
, &buf
, sizeof(buf
));
325 static void child_dup2(int fd
, int to
)
327 if (dup2(fd
, to
) < 0)
328 child_die(CHILD_ERR_DUP2
);
331 static void child_close(int fd
)
334 child_die(CHILD_ERR_CLOSE
);
337 static void child_close_pair(int fd
[2])
343 static void child_error_fn(const char *err
, va_list params
)
345 const char msg
[] = "error() should not be called in child\n";
346 xwrite(2, msg
, sizeof(msg
) - 1);
349 static void child_warn_fn(const char *err
, va_list params
)
351 const char msg
[] = "warn() should not be called in child\n";
352 xwrite(2, msg
, sizeof(msg
) - 1);
355 static void NORETURN
child_die_fn(const char *err
, va_list params
)
357 const char msg
[] = "die() should not be called in child\n";
358 xwrite(2, msg
, sizeof(msg
) - 1);
362 /* this runs in the parent process */
363 static void child_err_spew(struct child_process
*cmd
, struct child_err
*cerr
)
365 static void (*old_errfn
)(const char *err
, va_list params
);
366 report_fn die_message_routine
= get_die_message_routine();
368 old_errfn
= get_error_routine();
369 set_error_routine(die_message_routine
);
370 errno
= cerr
->syserr
;
373 case CHILD_ERR_CHDIR
:
374 error_errno("exec '%s': cd to '%s' failed",
375 cmd
->args
.v
[0], cmd
->dir
);
378 error_errno("dup2() in child failed");
380 case CHILD_ERR_CLOSE
:
381 error_errno("close() in child failed");
383 case CHILD_ERR_SIGPROCMASK
:
384 error_errno("sigprocmask failed restoring signals");
386 case CHILD_ERR_ENOENT
:
387 error_errno("cannot run %s", cmd
->args
.v
[0]);
389 case CHILD_ERR_SILENT
:
391 case CHILD_ERR_ERRNO
:
392 error_errno("cannot exec '%s'", cmd
->args
.v
[0]);
395 set_error_routine(old_errfn
);
398 static int prepare_cmd(struct strvec
*out
, const struct child_process
*cmd
)
401 BUG("command is empty");
404 * Add SHELL_PATH so in the event exec fails with ENOEXEC we can
405 * attempt to interpret the command with 'sh'.
407 strvec_push(out
, SHELL_PATH
);
410 prepare_git_cmd(out
, cmd
->args
.v
);
411 } else if (cmd
->use_shell
) {
412 prepare_shell_cmd(out
, cmd
->args
.v
);
414 strvec_pushv(out
, cmd
->args
.v
);
418 * If there are no dir separator characters in the command then perform
419 * a path lookup and use the resolved path as the command to exec. If
420 * there are dir separator characters, we have exec attempt to invoke
421 * the command directly.
423 if (!has_dir_sep(out
->v
[1])) {
424 char *program
= locate_in_PATH(out
->v
[1]);
426 free((char *)out
->v
[1]);
438 static char **prep_childenv(const char *const *deltaenv
)
440 extern char **environ
;
442 struct string_list env
= STRING_LIST_INIT_DUP
;
443 struct strbuf key
= STRBUF_INIT
;
444 const char *const *p
;
447 /* Construct a sorted string list consisting of the current environ */
448 for (p
= (const char *const *) environ
; p
&& *p
; p
++) {
449 const char *equals
= strchr(*p
, '=');
453 strbuf_add(&key
, *p
, equals
- *p
);
454 string_list_append(&env
, key
.buf
)->util
= (void *) *p
;
456 string_list_append(&env
, *p
)->util
= (void *) *p
;
459 string_list_sort(&env
);
461 /* Merge in 'deltaenv' with the current environ */
462 for (p
= deltaenv
; p
&& *p
; p
++) {
463 const char *equals
= strchr(*p
, '=');
466 /* ('key=value'), insert or replace entry */
468 strbuf_add(&key
, *p
, equals
- *p
);
469 string_list_insert(&env
, key
.buf
)->util
= (void *) *p
;
471 /* otherwise ('key') remove existing entry */
472 string_list_remove(&env
, *p
, 0);
476 /* Create an array of 'char *' to be used as the childenv */
477 ALLOC_ARRAY(childenv
, env
.nr
+ 1);
478 for (i
= 0; i
< env
.nr
; i
++)
479 childenv
[i
] = env
.items
[i
].util
;
480 childenv
[env
.nr
] = NULL
;
482 string_list_clear(&env
, 0);
483 strbuf_release(&key
);
487 struct atfork_state
{
494 #define CHECK_BUG(err, msg) \
498 BUG("%s: %s", msg, strerror(e)); \
501 static void atfork_prepare(struct atfork_state
*as
)
505 if (sigfillset(&all
))
506 die_errno("sigfillset");
508 if (sigprocmask(SIG_SETMASK
, &all
, &as
->old
))
509 die_errno("sigprocmask");
511 CHECK_BUG(pthread_sigmask(SIG_SETMASK
, &all
, &as
->old
),
512 "blocking all signals");
513 CHECK_BUG(pthread_setcancelstate(PTHREAD_CANCEL_DISABLE
, &as
->cs
),
514 "disabling cancellation");
518 static void atfork_parent(struct atfork_state
*as
)
521 if (sigprocmask(SIG_SETMASK
, &as
->old
, NULL
))
522 die_errno("sigprocmask");
524 CHECK_BUG(pthread_setcancelstate(as
->cs
, NULL
),
525 "re-enabling cancellation");
526 CHECK_BUG(pthread_sigmask(SIG_SETMASK
, &as
->old
, NULL
),
527 "restoring signal mask");
530 #endif /* GIT_WINDOWS_NATIVE */
532 static inline void set_cloexec(int fd
)
534 int flags
= fcntl(fd
, F_GETFD
);
536 fcntl(fd
, F_SETFD
, flags
| FD_CLOEXEC
);
539 static int wait_or_whine(pid_t pid
, const char *argv0
, int in_signal
)
541 int status
, code
= -1;
543 int failed_errno
= 0;
545 while ((waiting
= waitpid(pid
, &status
, 0)) < 0 && errno
== EINTR
)
549 failed_errno
= errno
;
551 error_errno("waitpid for %s failed", argv0
);
552 } else if (waiting
!= pid
) {
554 error("waitpid is confused (%s)", argv0
);
555 } else if (WIFSIGNALED(status
)) {
556 code
= WTERMSIG(status
);
557 if (!in_signal
&& code
!= SIGINT
&& code
!= SIGQUIT
&& code
!= SIGPIPE
)
558 error("%s died of signal %d", argv0
, code
);
560 * This return value is chosen so that code & 0xff
561 * mimics the exit code that a POSIX shell would report for
562 * a program that died from this signal.
565 } else if (WIFEXITED(status
)) {
566 code
= WEXITSTATUS(status
);
569 error("waitpid is confused (%s)", argv0
);
573 clear_child_for_cleanup(pid
);
575 errno
= failed_errno
;
579 static void trace_add_env(struct strbuf
*dst
, const char *const *deltaenv
)
581 struct string_list envs
= STRING_LIST_INIT_DUP
;
582 const char *const *e
;
584 int printed_unset
= 0;
586 /* Last one wins, see run-command.c:prep_childenv() for context */
587 for (e
= deltaenv
; e
&& *e
; e
++) {
588 struct strbuf key
= STRBUF_INIT
;
589 char *equals
= strchr(*e
, '=');
592 strbuf_add(&key
, *e
, equals
- *e
);
593 string_list_insert(&envs
, key
.buf
)->util
= equals
+ 1;
595 string_list_insert(&envs
, *e
)->util
= NULL
;
597 strbuf_release(&key
);
600 /* "unset X Y...;" */
601 for (i
= 0; i
< envs
.nr
; i
++) {
602 const char *var
= envs
.items
[i
].string
;
603 const char *val
= envs
.items
[i
].util
;
605 if (val
|| !getenv(var
))
608 if (!printed_unset
) {
609 strbuf_addstr(dst
, " unset");
612 strbuf_addf(dst
, " %s", var
);
615 strbuf_addch(dst
, ';');
617 /* ... followed by "A=B C=D ..." */
618 for (i
= 0; i
< envs
.nr
; i
++) {
619 const char *var
= envs
.items
[i
].string
;
620 const char *val
= envs
.items
[i
].util
;
626 oldval
= getenv(var
);
627 if (oldval
&& !strcmp(val
, oldval
))
630 strbuf_addf(dst
, " %s=", var
);
631 sq_quote_buf_pretty(dst
, val
);
633 string_list_clear(&envs
, 0);
636 static void trace_run_command(const struct child_process
*cp
)
638 struct strbuf buf
= STRBUF_INIT
;
640 if (!trace_want(&trace_default_key
))
643 strbuf_addstr(&buf
, "trace: run_command:");
645 strbuf_addstr(&buf
, " cd ");
646 sq_quote_buf_pretty(&buf
, cp
->dir
);
647 strbuf_addch(&buf
, ';');
649 trace_add_env(&buf
, cp
->env
.v
);
651 strbuf_addstr(&buf
, " git");
652 sq_quote_argv_pretty(&buf
, cp
->args
.v
);
654 trace_printf("%s", buf
.buf
);
655 strbuf_release(&buf
);
658 int start_command(struct child_process
*cmd
)
660 int need_in
, need_out
, need_err
;
661 int fdin
[2], fdout
[2], fderr
[2];
666 * In case of errors we must keep the promise to close FDs
667 * that have been passed in via ->in and ->out.
670 need_in
= !cmd
->no_stdin
&& cmd
->in
< 0;
672 if (pipe(fdin
) < 0) {
673 failed_errno
= errno
;
676 str
= "standard input";
682 need_out
= !cmd
->no_stdout
683 && !cmd
->stdout_to_stderr
686 if (pipe(fdout
) < 0) {
687 failed_errno
= errno
;
692 str
= "standard output";
698 need_err
= !cmd
->no_stderr
&& cmd
->err
< 0;
700 if (pipe(fderr
) < 0) {
701 failed_errno
= errno
;
710 str
= "standard error";
712 error("cannot create %s pipe for %s: %s",
713 str
, cmd
->args
.v
[0], strerror(failed_errno
));
714 child_process_clear(cmd
);
715 errno
= failed_errno
;
721 trace2_child_start(cmd
);
722 trace_run_command(cmd
);
726 if (cmd
->close_object_store
)
727 close_object_store(the_repository
->objects
);
729 #ifndef GIT_WINDOWS_NATIVE
734 struct strvec argv
= STRVEC_INIT
;
735 struct child_err cerr
;
736 struct atfork_state as
;
738 if (prepare_cmd(&argv
, cmd
) < 0) {
739 failed_errno
= errno
;
741 if (!cmd
->silent_exec_failure
)
742 error_errno("cannot run %s", cmd
->args
.v
[0]);
746 if (pipe(notify_pipe
))
747 notify_pipe
[0] = notify_pipe
[1] = -1;
749 if (cmd
->no_stdin
|| cmd
->no_stdout
|| cmd
->no_stderr
) {
750 null_fd
= xopen("/dev/null", O_RDWR
| O_CLOEXEC
);
751 set_cloexec(null_fd
);
754 childenv
= prep_childenv(cmd
->env
.v
);
758 * NOTE: In order to prevent deadlocking when using threads special
759 * care should be taken with the function calls made in between the
760 * fork() and exec() calls. No calls should be made to functions which
761 * require acquiring a lock (e.g. malloc) as the lock could have been
762 * held by another thread at the time of forking, causing the lock to
763 * never be released in the child process. This means only
764 * Async-Signal-Safe functions are permitted in the child.
767 failed_errno
= errno
;
771 * Ensure the default die/error/warn routines do not get
772 * called, they can take stdio locks and malloc.
774 set_die_routine(child_die_fn
);
775 set_error_routine(child_error_fn
);
776 set_warn_routine(child_warn_fn
);
778 close(notify_pipe
[0]);
779 set_cloexec(notify_pipe
[1]);
780 child_notifier
= notify_pipe
[1];
783 child_dup2(null_fd
, 0);
785 child_dup2(fdin
[0], 0);
786 child_close_pair(fdin
);
787 } else if (cmd
->in
) {
788 child_dup2(cmd
->in
, 0);
789 child_close(cmd
->in
);
793 child_dup2(null_fd
, 2);
795 child_dup2(fderr
[1], 2);
796 child_close_pair(fderr
);
797 } else if (cmd
->err
> 1) {
798 child_dup2(cmd
->err
, 2);
799 child_close(cmd
->err
);
803 child_dup2(null_fd
, 1);
804 else if (cmd
->stdout_to_stderr
)
807 child_dup2(fdout
[1], 1);
808 child_close_pair(fdout
);
809 } else if (cmd
->out
> 1) {
810 child_dup2(cmd
->out
, 1);
811 child_close(cmd
->out
);
814 if (cmd
->dir
&& chdir(cmd
->dir
))
815 child_die(CHILD_ERR_CHDIR
);
818 * restore default signal handlers here, in case
819 * we catch a signal right before execve below
821 for (sig
= 1; sig
< NSIG
; sig
++) {
822 /* ignored signals get reset to SIG_DFL on execve */
823 if (signal(sig
, SIG_DFL
) == SIG_IGN
)
824 signal(sig
, SIG_IGN
);
827 if (sigprocmask(SIG_SETMASK
, &as
.old
, NULL
) != 0)
828 child_die(CHILD_ERR_SIGPROCMASK
);
831 * Attempt to exec using the command and arguments starting at
832 * argv.argv[1]. argv.argv[0] contains SHELL_PATH which will
833 * be used in the event exec failed with ENOEXEC at which point
834 * we will try to interpret the command using 'sh'.
836 execve(argv
.v
[1], (char *const *) argv
.v
+ 1,
837 (char *const *) childenv
);
838 if (errno
== ENOEXEC
)
839 execve(argv
.v
[0], (char *const *) argv
.v
,
840 (char *const *) childenv
);
842 if (errno
== ENOENT
) {
843 if (cmd
->silent_exec_failure
)
844 child_die(CHILD_ERR_SILENT
);
845 child_die(CHILD_ERR_ENOENT
);
847 child_die(CHILD_ERR_ERRNO
);
852 error_errno("cannot fork() for %s", cmd
->args
.v
[0]);
853 else if (cmd
->clean_on_exit
)
854 mark_child_for_cleanup(cmd
->pid
, cmd
);
857 * Wait for child's exec. If the exec succeeds (or if fork()
858 * failed), EOF is seen immediately by the parent. Otherwise, the
859 * child process sends a child_err struct.
860 * Note that use of this infrastructure is completely advisory,
861 * therefore, we keep error checks minimal.
863 close(notify_pipe
[1]);
864 if (xread(notify_pipe
[0], &cerr
, sizeof(cerr
)) == sizeof(cerr
)) {
866 * At this point we know that fork() succeeded, but exec()
867 * failed. Errors have been reported to our stderr.
869 wait_or_whine(cmd
->pid
, cmd
->args
.v
[0], 0);
870 child_err_spew(cmd
, &cerr
);
871 failed_errno
= errno
;
874 close(notify_pipe
[0]);
885 int fhin
= 0, fhout
= 1, fherr
= 2;
886 const char **sargv
= cmd
->args
.v
;
887 struct strvec nargv
= STRVEC_INIT
;
890 fhin
= open("/dev/null", O_RDWR
);
897 fherr
= open("/dev/null", O_RDWR
);
899 fherr
= dup(fderr
[1]);
900 else if (cmd
->err
> 2)
901 fherr
= dup(cmd
->err
);
904 fhout
= open("/dev/null", O_RDWR
);
905 else if (cmd
->stdout_to_stderr
)
908 fhout
= dup(fdout
[1]);
909 else if (cmd
->out
> 1)
910 fhout
= dup(cmd
->out
);
913 cmd
->args
.v
= prepare_git_cmd(&nargv
, sargv
);
914 else if (cmd
->use_shell
)
915 cmd
->args
.v
= prepare_shell_cmd(&nargv
, sargv
);
917 cmd
->pid
= mingw_spawnvpe(cmd
->args
.v
[0], cmd
->args
.v
,
919 cmd
->dir
, fhin
, fhout
, fherr
);
920 failed_errno
= errno
;
921 if (cmd
->pid
< 0 && (!cmd
->silent_exec_failure
|| errno
!= ENOENT
))
922 error_errno("cannot spawn %s", cmd
->args
.v
[0]);
923 if (cmd
->clean_on_exit
&& cmd
->pid
>= 0)
924 mark_child_for_cleanup(cmd
->pid
, cmd
);
926 strvec_clear(&nargv
);
938 trace2_child_exit(cmd
, -1);
952 child_process_clear(cmd
);
953 errno
= failed_errno
;
975 int finish_command(struct child_process
*cmd
)
977 int ret
= wait_or_whine(cmd
->pid
, cmd
->args
.v
[0], 0);
978 trace2_child_exit(cmd
, ret
);
979 child_process_clear(cmd
);
980 invalidate_lstat_cache();
984 int finish_command_in_signal(struct child_process
*cmd
)
986 int ret
= wait_or_whine(cmd
->pid
, cmd
->args
.v
[0], 1);
987 trace2_child_exit(cmd
, ret
);
992 int run_command(struct child_process
*cmd
)
996 if (cmd
->out
< 0 || cmd
->err
< 0)
997 BUG("run_command with a pipe can cause deadlock");
999 code
= start_command(cmd
);
1002 return finish_command(cmd
);
1005 int run_command_v_opt(const char **argv
, int opt
)
1007 return run_command_v_opt_cd_env(argv
, opt
, NULL
, NULL
);
1010 int run_command_v_opt_tr2(const char **argv
, int opt
, const char *tr2_class
)
1012 return run_command_v_opt_cd_env_tr2(argv
, opt
, NULL
, NULL
, tr2_class
);
1015 int run_command_v_opt_cd_env(const char **argv
, int opt
, const char *dir
, const char *const *env
)
1017 return run_command_v_opt_cd_env_tr2(argv
, opt
, dir
, env
, NULL
);
1020 int run_command_v_opt_cd_env_tr2(const char **argv
, int opt
, const char *dir
,
1021 const char *const *env
, const char *tr2_class
)
1023 struct child_process cmd
= CHILD_PROCESS_INIT
;
1024 strvec_pushv(&cmd
.args
, argv
);
1025 cmd
.no_stdin
= opt
& RUN_COMMAND_NO_STDIN
? 1 : 0;
1026 cmd
.git_cmd
= opt
& RUN_GIT_CMD
? 1 : 0;
1027 cmd
.stdout_to_stderr
= opt
& RUN_COMMAND_STDOUT_TO_STDERR
? 1 : 0;
1028 cmd
.silent_exec_failure
= opt
& RUN_SILENT_EXEC_FAILURE
? 1 : 0;
1029 cmd
.use_shell
= opt
& RUN_USING_SHELL
? 1 : 0;
1030 cmd
.clean_on_exit
= opt
& RUN_CLEAN_ON_EXIT
? 1 : 0;
1031 cmd
.wait_after_clean
= opt
& RUN_WAIT_AFTER_CLEAN
? 1 : 0;
1032 cmd
.close_object_store
= opt
& RUN_CLOSE_OBJECT_STORE
? 1 : 0;
1035 strvec_pushv(&cmd
.env
, (const char **)env
);
1036 cmd
.trace2_child_class
= tr2_class
;
1037 return run_command(&cmd
);
1041 static pthread_t main_thread
;
1042 static int main_thread_set
;
1043 static pthread_key_t async_key
;
1044 static pthread_key_t async_die_counter
;
1046 static void *run_thread(void *data
)
1048 struct async
*async
= data
;
1051 if (async
->isolate_sigpipe
) {
1054 sigaddset(&mask
, SIGPIPE
);
1055 if (pthread_sigmask(SIG_BLOCK
, &mask
, NULL
) < 0) {
1056 ret
= error("unable to block SIGPIPE in async thread");
1061 pthread_setspecific(async_key
, async
);
1062 ret
= async
->proc(async
->proc_in
, async
->proc_out
, async
->data
);
1066 static NORETURN
void die_async(const char *err
, va_list params
)
1068 report_fn die_message_fn
= get_die_message_routine();
1070 die_message_fn(err
, params
);
1073 struct async
*async
= pthread_getspecific(async_key
);
1074 if (async
->proc_in
>= 0)
1075 close(async
->proc_in
);
1076 if (async
->proc_out
>= 0)
1077 close(async
->proc_out
);
1078 pthread_exit((void *)128);
1084 static int async_die_is_recursing(void)
1086 void *ret
= pthread_getspecific(async_die_counter
);
1087 pthread_setspecific(async_die_counter
, &async_die_counter
); /* set to any non-NULL valid pointer */
1093 if (!main_thread_set
)
1094 return 0; /* no asyncs started yet */
1095 return !pthread_equal(main_thread
, pthread_self());
1098 static void NORETURN
async_exit(int code
)
1100 pthread_exit((void *)(intptr_t)code
);
1106 void (**handlers
)(void);
1111 static int git_atexit_installed
;
1113 static void git_atexit_dispatch(void)
1117 for (i
=git_atexit_hdlrs
.nr
; i
; i
--)
1118 git_atexit_hdlrs
.handlers
[i
-1]();
1121 static void git_atexit_clear(void)
1123 free(git_atexit_hdlrs
.handlers
);
1124 memset(&git_atexit_hdlrs
, 0, sizeof(git_atexit_hdlrs
));
1125 git_atexit_installed
= 0;
1129 int git_atexit(void (*handler
)(void))
1131 ALLOC_GROW(git_atexit_hdlrs
.handlers
, git_atexit_hdlrs
.nr
+ 1, git_atexit_hdlrs
.alloc
);
1132 git_atexit_hdlrs
.handlers
[git_atexit_hdlrs
.nr
++] = handler
;
1133 if (!git_atexit_installed
) {
1134 if (atexit(&git_atexit_dispatch
))
1136 git_atexit_installed
= 1;
1140 #define atexit git_atexit
1142 static int process_is_async
;
1145 return process_is_async
;
1148 static void NORETURN
async_exit(int code
)
1155 void check_pipe(int err
)
1161 signal(SIGPIPE
, SIG_DFL
);
1163 /* Should never happen, but just in case... */
1168 int start_async(struct async
*async
)
1170 int need_in
, need_out
;
1171 int fdin
[2], fdout
[2];
1172 int proc_in
, proc_out
;
1174 need_in
= async
->in
< 0;
1176 if (pipe(fdin
) < 0) {
1179 return error_errno("cannot create pipe");
1181 async
->in
= fdin
[1];
1184 need_out
= async
->out
< 0;
1186 if (pipe(fdout
) < 0) {
1191 return error_errno("cannot create pipe");
1193 async
->out
= fdout
[0];
1199 proc_in
= async
->in
;
1204 proc_out
= fdout
[1];
1205 else if (async
->out
)
1206 proc_out
= async
->out
;
1211 /* Flush stdio before fork() to avoid cloning buffers */
1214 async
->pid
= fork();
1215 if (async
->pid
< 0) {
1216 error_errno("fork (async) failed");
1225 process_is_async
= 1;
1226 exit(!!async
->proc(proc_in
, proc_out
, async
->data
));
1229 mark_child_for_cleanup(async
->pid
, NULL
);
1238 else if (async
->out
)
1241 if (!main_thread_set
) {
1243 * We assume that the first time that start_async is called
1244 * it is from the main thread.
1246 main_thread_set
= 1;
1247 main_thread
= pthread_self();
1248 pthread_key_create(&async_key
, NULL
);
1249 pthread_key_create(&async_die_counter
, NULL
);
1250 set_die_routine(die_async
);
1251 set_die_is_recursing_routine(async_die_is_recursing
);
1255 set_cloexec(proc_in
);
1257 set_cloexec(proc_out
);
1258 async
->proc_in
= proc_in
;
1259 async
->proc_out
= proc_out
;
1261 int err
= pthread_create(&async
->tid
, NULL
, run_thread
, async
);
1263 error(_("cannot create async thread: %s"), strerror(err
));
1278 else if (async
->out
)
1283 int finish_async(struct async
*async
)
1286 int ret
= wait_or_whine(async
->pid
, "child process", 0);
1288 invalidate_lstat_cache();
1292 void *ret
= (void *)(intptr_t)(-1);
1294 if (pthread_join(async
->tid
, &ret
))
1295 error("pthread_join failed");
1296 invalidate_lstat_cache();
1297 return (int)(intptr_t)ret
;
1302 int async_with_fork(void)
1312 /* initialized by caller */
1314 int type
; /* POLLOUT or POLLIN */
1326 /* returned by pump_io */
1327 int error
; /* 0 for success, otherwise errno */
1333 static int pump_io_round(struct io_pump
*slots
, int nr
, struct pollfd
*pfd
)
1338 for (i
= 0; i
< nr
; i
++) {
1339 struct io_pump
*io
= &slots
[i
];
1342 pfd
[pollsize
].fd
= io
->fd
;
1343 pfd
[pollsize
].events
= io
->type
;
1344 io
->pfd
= &pfd
[pollsize
++];
1350 if (poll(pfd
, pollsize
, -1) < 0) {
1353 die_errno("poll failed");
1356 for (i
= 0; i
< nr
; i
++) {
1357 struct io_pump
*io
= &slots
[i
];
1362 if (!(io
->pfd
->revents
& (POLLOUT
|POLLIN
|POLLHUP
|POLLERR
|POLLNVAL
)))
1365 if (io
->type
== POLLOUT
) {
1366 ssize_t len
= xwrite(io
->fd
,
1367 io
->u
.out
.buf
, io
->u
.out
.len
);
1373 io
->u
.out
.buf
+= len
;
1374 io
->u
.out
.len
-= len
;
1375 if (!io
->u
.out
.len
) {
1382 if (io
->type
== POLLIN
) {
1383 ssize_t len
= strbuf_read_once(io
->u
.in
.buf
,
1384 io
->fd
, io
->u
.in
.hint
);
1397 static int pump_io(struct io_pump
*slots
, int nr
)
1402 for (i
= 0; i
< nr
; i
++)
1405 ALLOC_ARRAY(pfd
, nr
);
1406 while (pump_io_round(slots
, nr
, pfd
))
1410 /* There may be multiple errno values, so just pick the first. */
1411 for (i
= 0; i
< nr
; i
++) {
1412 if (slots
[i
].error
) {
1413 errno
= slots
[i
].error
;
1421 int pipe_command(struct child_process
*cmd
,
1422 const char *in
, size_t in_len
,
1423 struct strbuf
*out
, size_t out_hint
,
1424 struct strbuf
*err
, size_t err_hint
)
1426 struct io_pump io
[3];
1436 if (start_command(cmd
) < 0)
1440 io
[nr
].fd
= cmd
->in
;
1441 io
[nr
].type
= POLLOUT
;
1442 io
[nr
].u
.out
.buf
= in
;
1443 io
[nr
].u
.out
.len
= in_len
;
1447 io
[nr
].fd
= cmd
->out
;
1448 io
[nr
].type
= POLLIN
;
1449 io
[nr
].u
.in
.buf
= out
;
1450 io
[nr
].u
.in
.hint
= out_hint
;
1454 io
[nr
].fd
= cmd
->err
;
1455 io
[nr
].type
= POLLIN
;
1456 io
[nr
].u
.in
.buf
= err
;
1457 io
[nr
].u
.in
.hint
= err_hint
;
1461 if (pump_io(io
, nr
) < 0) {
1462 finish_command(cmd
); /* throw away exit code */
1466 return finish_command(cmd
);
1472 GIT_CP_WAIT_CLEANUP
,
1475 struct parallel_processes
{
1481 get_next_task_fn get_next_task
;
1482 start_failure_fn start_failure
;
1483 task_finished_fn task_finished
;
1486 enum child_state state
;
1487 struct child_process process
;
1492 * The struct pollfd is logically part of *children,
1493 * but the system call expects it as its own array.
1497 unsigned shutdown
: 1;
1500 struct strbuf buffered_output
; /* of finished children */
1503 static int default_start_failure(struct strbuf
*out
,
1510 static int default_task_finished(int result
,
1518 static void kill_children(struct parallel_processes
*pp
, int signo
)
1520 int i
, n
= pp
->max_processes
;
1522 for (i
= 0; i
< n
; i
++)
1523 if (pp
->children
[i
].state
== GIT_CP_WORKING
)
1524 kill(pp
->children
[i
].process
.pid
, signo
);
1527 static struct parallel_processes
*pp_for_signal
;
1529 static void handle_children_on_signal(int signo
)
1531 kill_children(pp_for_signal
, signo
);
1532 sigchain_pop(signo
);
1536 static void pp_init(struct parallel_processes
*pp
,
1538 get_next_task_fn get_next_task
,
1539 start_failure_fn start_failure
,
1540 task_finished_fn task_finished
,
1548 pp
->max_processes
= n
;
1550 trace_printf("run_processes_parallel: preparing to run up to %d tasks", n
);
1554 BUG("you need to specify a get_next_task function");
1555 pp
->get_next_task
= get_next_task
;
1557 pp
->start_failure
= start_failure
? start_failure
: default_start_failure
;
1558 pp
->task_finished
= task_finished
? task_finished
: default_task_finished
;
1560 pp
->nr_processes
= 0;
1561 pp
->output_owner
= 0;
1563 CALLOC_ARRAY(pp
->children
, n
);
1564 CALLOC_ARRAY(pp
->pfd
, n
);
1565 strbuf_init(&pp
->buffered_output
, 0);
1567 for (i
= 0; i
< n
; i
++) {
1568 strbuf_init(&pp
->children
[i
].err
, 0);
1569 child_process_init(&pp
->children
[i
].process
);
1570 pp
->pfd
[i
].events
= POLLIN
| POLLHUP
;
1575 sigchain_push_common(handle_children_on_signal
);
1578 static void pp_cleanup(struct parallel_processes
*pp
)
1582 trace_printf("run_processes_parallel: done");
1583 for (i
= 0; i
< pp
->max_processes
; i
++) {
1584 strbuf_release(&pp
->children
[i
].err
);
1585 child_process_clear(&pp
->children
[i
].process
);
1592 * When get_next_task added messages to the buffer in its last
1593 * iteration, the buffered output is non empty.
1595 strbuf_write(&pp
->buffered_output
, stderr
);
1596 strbuf_release(&pp
->buffered_output
);
1598 sigchain_pop_common();
1602 * 0 if a new task was started.
1603 * 1 if no new jobs was started (get_next_task ran out of work, non critical
1604 * problem with starting a new command)
1605 * <0 no new job was started, user wishes to shutdown early. Use negative code
1606 * to signal the children.
1608 static int pp_start_one(struct parallel_processes
*pp
)
1612 for (i
= 0; i
< pp
->max_processes
; i
++)
1613 if (pp
->children
[i
].state
== GIT_CP_FREE
)
1615 if (i
== pp
->max_processes
)
1616 BUG("bookkeeping is hard");
1618 code
= pp
->get_next_task(&pp
->children
[i
].process
,
1619 &pp
->children
[i
].err
,
1621 &pp
->children
[i
].data
);
1623 strbuf_addbuf(&pp
->buffered_output
, &pp
->children
[i
].err
);
1624 strbuf_reset(&pp
->children
[i
].err
);
1627 pp
->children
[i
].process
.err
= -1;
1628 pp
->children
[i
].process
.stdout_to_stderr
= 1;
1629 pp
->children
[i
].process
.no_stdin
= 1;
1631 if (start_command(&pp
->children
[i
].process
)) {
1632 code
= pp
->start_failure(&pp
->children
[i
].err
,
1634 pp
->children
[i
].data
);
1635 strbuf_addbuf(&pp
->buffered_output
, &pp
->children
[i
].err
);
1636 strbuf_reset(&pp
->children
[i
].err
);
1643 pp
->children
[i
].state
= GIT_CP_WORKING
;
1644 pp
->pfd
[i
].fd
= pp
->children
[i
].process
.err
;
1648 static void pp_buffer_stderr(struct parallel_processes
*pp
, int output_timeout
)
1652 while ((i
= poll(pp
->pfd
, pp
->max_processes
, output_timeout
)) < 0) {
1659 /* Buffer output from all pipes. */
1660 for (i
= 0; i
< pp
->max_processes
; i
++) {
1661 if (pp
->children
[i
].state
== GIT_CP_WORKING
&&
1662 pp
->pfd
[i
].revents
& (POLLIN
| POLLHUP
)) {
1663 int n
= strbuf_read_once(&pp
->children
[i
].err
,
1664 pp
->children
[i
].process
.err
, 0);
1666 close(pp
->children
[i
].process
.err
);
1667 pp
->children
[i
].state
= GIT_CP_WAIT_CLEANUP
;
1669 if (errno
!= EAGAIN
)
1675 static void pp_output(struct parallel_processes
*pp
)
1677 int i
= pp
->output_owner
;
1678 if (pp
->children
[i
].state
== GIT_CP_WORKING
&&
1679 pp
->children
[i
].err
.len
) {
1680 strbuf_write(&pp
->children
[i
].err
, stderr
);
1681 strbuf_reset(&pp
->children
[i
].err
);
1685 static int pp_collect_finished(struct parallel_processes
*pp
)
1688 int n
= pp
->max_processes
;
1691 while (pp
->nr_processes
> 0) {
1692 for (i
= 0; i
< pp
->max_processes
; i
++)
1693 if (pp
->children
[i
].state
== GIT_CP_WAIT_CLEANUP
)
1695 if (i
== pp
->max_processes
)
1698 code
= finish_command(&pp
->children
[i
].process
);
1700 code
= pp
->task_finished(code
,
1701 &pp
->children
[i
].err
, pp
->data
,
1702 pp
->children
[i
].data
);
1710 pp
->children
[i
].state
= GIT_CP_FREE
;
1712 child_process_init(&pp
->children
[i
].process
);
1714 if (i
!= pp
->output_owner
) {
1715 strbuf_addbuf(&pp
->buffered_output
, &pp
->children
[i
].err
);
1716 strbuf_reset(&pp
->children
[i
].err
);
1718 strbuf_write(&pp
->children
[i
].err
, stderr
);
1719 strbuf_reset(&pp
->children
[i
].err
);
1721 /* Output all other finished child processes */
1722 strbuf_write(&pp
->buffered_output
, stderr
);
1723 strbuf_reset(&pp
->buffered_output
);
1726 * Pick next process to output live.
1728 * For now we pick it randomly by doing a round
1729 * robin. Later we may want to pick the one with
1730 * the most output or the longest or shortest
1731 * running process time.
1733 for (i
= 0; i
< n
; i
++)
1734 if (pp
->children
[(pp
->output_owner
+ i
) % n
].state
== GIT_CP_WORKING
)
1736 pp
->output_owner
= (pp
->output_owner
+ i
) % n
;
1742 int run_processes_parallel(int n
,
1743 get_next_task_fn get_next_task
,
1744 start_failure_fn start_failure
,
1745 task_finished_fn task_finished
,
1749 int output_timeout
= 100;
1751 struct parallel_processes pp
;
1753 pp_init(&pp
, n
, get_next_task
, start_failure
, task_finished
, pp_cb
);
1756 i
< spawn_cap
&& !pp
.shutdown
&&
1757 pp
.nr_processes
< pp
.max_processes
;
1759 code
= pp_start_one(&pp
);
1764 kill_children(&pp
, -code
);
1768 if (!pp
.nr_processes
)
1770 pp_buffer_stderr(&pp
, output_timeout
);
1772 code
= pp_collect_finished(&pp
);
1776 kill_children(&pp
, -code
);
1784 int run_processes_parallel_tr2(int n
, get_next_task_fn get_next_task
,
1785 start_failure_fn start_failure
,
1786 task_finished_fn task_finished
, void *pp_cb
,
1787 const char *tr2_category
, const char *tr2_label
)
1791 trace2_region_enter_printf(tr2_category
, tr2_label
, NULL
, "max:%d",
1792 ((n
< 1) ? online_cpus() : n
));
1794 result
= run_processes_parallel(n
, get_next_task
, start_failure
,
1795 task_finished
, pp_cb
);
1797 trace2_region_leave(tr2_category
, tr2_label
, NULL
);
1802 int run_auto_maintenance(int quiet
)
1805 struct child_process maint
= CHILD_PROCESS_INIT
;
1807 if (!git_config_get_bool("maintenance.auto", &enabled
) &&
1812 maint
.close_object_store
= 1;
1813 strvec_pushl(&maint
.args
, "maintenance", "run", "--auto", NULL
);
1814 strvec_push(&maint
.args
, quiet
? "--quiet" : "--no-quiet");
1816 return run_command(&maint
);
1819 void prepare_other_repo_env(struct strvec
*env
, const char *new_git_dir
)
1821 const char * const *var
;
1823 for (var
= local_repo_env
; *var
; var
++) {
1824 if (strcmp(*var
, CONFIG_DATA_ENVIRONMENT
) &&
1825 strcmp(*var
, CONFIG_COUNT_ENVIRONMENT
))
1826 strvec_push(env
, *var
);
1828 strvec_pushf(env
, "%s=%s", GIT_DIR_ENVIRONMENT
, new_git_dir
);
1831 enum start_bg_result
start_bg_command(struct child_process
*cmd
,
1832 start_bg_wait_cb
*wait_cb
,
1834 unsigned int timeout_sec
)
1836 enum start_bg_result sbgr
= SBGR_ERROR
;
1843 * We do not allow clean-on-exit because the child process
1844 * should persist in the background and possibly/probably
1845 * after this process exits. So we don't want to kill the
1846 * child during our atexit routine.
1848 if (cmd
->clean_on_exit
)
1849 BUG("start_bg_command() does not allow non-zero clean_on_exit");
1851 if (!cmd
->trace2_child_class
)
1852 cmd
->trace2_child_class
= "background";
1854 ret
= start_command(cmd
);
1857 * We assume that if `start_command()` fails, we
1858 * either get a complete `trace2_child_start() /
1859 * trace2_child_exit()` pair or it fails before the
1860 * `trace2_child_start()` is emitted, so we do not
1861 * need to worry about it here.
1863 * We also assume that `start_command()` does not add
1864 * us to the cleanup list. And that it calls
1865 * calls `child_process_clear()`.
1872 time_limit
+= timeout_sec
;
1875 pid_seen
= waitpid(cmd
->pid
, &wait_status
, WNOHANG
);
1879 * The child is currently running. Ask the callback
1880 * if the child is ready to do work or whether we
1881 * should keep waiting for it to boot up.
1883 ret
= (*wait_cb
)(cmd
, cb_data
);
1886 * The child is running and "ready".
1888 trace2_child_ready(cmd
, "ready");
1891 } else if (ret
> 0) {
1893 * The callback said to give it more time to boot up
1894 * (subject to our timeout limit).
1899 if (now
< time_limit
)
1903 * Our timeout has expired. We don't try to
1904 * kill the child, but rather let it continue
1905 * (hopefully) trying to startup.
1907 trace2_child_ready(cmd
, "timeout");
1908 sbgr
= SBGR_TIMEOUT
;
1912 * The cb gave up on this child. It is still running,
1913 * but our cb got an error trying to probe it.
1915 trace2_child_ready(cmd
, "error");
1916 sbgr
= SBGR_CB_ERROR
;
1921 else if (pid_seen
== cmd
->pid
) {
1922 int child_code
= -1;
1925 * The child started, but exited or was terminated
1926 * before becoming "ready".
1928 * We try to match the behavior of `wait_or_whine()`
1929 * WRT the handling of WIFSIGNALED() and WIFEXITED()
1930 * and convert the child's status to a return code for
1931 * tracing purposes and emit the `trace2_child_exit()`
1934 * We do not want the wait_or_whine() error message
1935 * because we will be called by client-side library
1938 if (WIFEXITED(wait_status
))
1939 child_code
= WEXITSTATUS(wait_status
);
1940 else if (WIFSIGNALED(wait_status
))
1941 child_code
= WTERMSIG(wait_status
) + 128;
1942 trace2_child_exit(cmd
, child_code
);
1948 else if (pid_seen
< 0 && errno
== EINTR
)
1951 trace2_child_exit(cmd
, -1);
1955 child_process_clear(cmd
);
1956 invalidate_lstat_cache();