2 #include "run-command.h"
5 #include "argv-array.h"
6 #include "thread-utils.h"
9 void child_process_init(struct child_process
*child
)
11 memset(child
, 0, sizeof(*child
));
12 argv_array_init(&child
->args
);
13 argv_array_init(&child
->env_array
);
16 void child_process_clear(struct child_process
*child
)
18 argv_array_clear(&child
->args
);
19 argv_array_clear(&child
->env_array
);
22 struct child_to_clean
{
24 struct child_process
*process
;
25 struct child_to_clean
*next
;
27 static struct child_to_clean
*children_to_clean
;
28 static int installed_child_cleanup_handler
;
30 static void cleanup_children(int sig
, int in_signal
)
32 struct child_to_clean
*children_to_wait_for
= NULL
;
34 while (children_to_clean
) {
35 struct child_to_clean
*p
= children_to_clean
;
36 children_to_clean
= p
->next
;
38 if (p
->process
&& !in_signal
) {
39 struct child_process
*process
= p
->process
;
40 if (process
->clean_on_exit_handler
) {
42 "trace: run_command: running exit handler for pid %"
43 PRIuMAX
, (uintmax_t)p
->pid
45 process
->clean_on_exit_handler(process
);
51 if (p
->process
&& p
->process
->wait_after_clean
) {
52 p
->next
= children_to_wait_for
;
53 children_to_wait_for
= p
;
60 while (children_to_wait_for
) {
61 struct child_to_clean
*p
= children_to_wait_for
;
62 children_to_wait_for
= p
->next
;
64 while (waitpid(p
->pid
, NULL
, 0) < 0 && errno
== EINTR
)
65 ; /* spin waiting for process exit or error */
72 static void cleanup_children_on_signal(int sig
)
74 cleanup_children(sig
, 1);
79 static void cleanup_children_on_exit(void)
81 cleanup_children(SIGTERM
, 0);
84 static void mark_child_for_cleanup(pid_t pid
, struct child_process
*process
)
86 struct child_to_clean
*p
= xmalloc(sizeof(*p
));
89 p
->next
= children_to_clean
;
90 children_to_clean
= p
;
92 if (!installed_child_cleanup_handler
) {
93 atexit(cleanup_children_on_exit
);
94 sigchain_push_common(cleanup_children_on_signal
);
95 installed_child_cleanup_handler
= 1;
99 static void clear_child_for_cleanup(pid_t pid
)
101 struct child_to_clean
**pp
;
103 for (pp
= &children_to_clean
; *pp
; pp
= &(*pp
)->next
) {
104 struct child_to_clean
*clean_me
= *pp
;
106 if (clean_me
->pid
== pid
) {
107 *pp
= clean_me
->next
;
114 static inline void close_pair(int fd
[2])
120 #ifndef GIT_WINDOWS_NATIVE
121 static inline void dup_devnull(int to
)
123 int fd
= open("/dev/null", O_RDWR
);
125 die_errno(_("open /dev/null failed"));
126 if (dup2(fd
, to
) < 0)
127 die_errno(_("dup2(%d,%d) failed"), fd
, to
);
132 static char *locate_in_PATH(const char *file
)
134 const char *p
= getenv("PATH");
135 struct strbuf buf
= STRBUF_INIT
;
141 const char *end
= strchrnul(p
, ':');
145 /* POSIX specifies an empty entry as the current directory. */
147 strbuf_add(&buf
, p
, end
- p
);
148 strbuf_addch(&buf
, '/');
150 strbuf_addstr(&buf
, file
);
152 if (!access(buf
.buf
, F_OK
))
153 return strbuf_detach(&buf
, NULL
);
160 strbuf_release(&buf
);
164 static int exists_in_PATH(const char *file
)
166 char *r
= locate_in_PATH(file
);
171 int sane_execvp(const char *file
, char * const argv
[])
173 if (!execvp(file
, argv
))
174 return 0; /* cannot happen ;-) */
177 * When a command can't be found because one of the directories
178 * listed in $PATH is unsearchable, execvp reports EACCES, but
179 * careful usability testing (read: analysis of occasional bug
180 * reports) reveals that "No such file or directory" is more
183 * We avoid commands with "/", because execvp will not do $PATH
184 * lookups in that case.
186 * The reassignment of EACCES to errno looks like a no-op below,
187 * but we need to protect against exists_in_PATH overwriting errno.
189 if (errno
== EACCES
&& !strchr(file
, '/'))
190 errno
= exists_in_PATH(file
) ? EACCES
: ENOENT
;
191 else if (errno
== ENOTDIR
&& !strchr(file
, '/'))
196 static const char **prepare_shell_cmd(struct argv_array
*out
, const char **argv
)
199 die("BUG: shell command is empty");
201 if (strcspn(argv
[0], "|&;<>()$`\\\"' \t\n*?[#~=%") != strlen(argv
[0])) {
202 #ifndef GIT_WINDOWS_NATIVE
203 argv_array_push(out
, SHELL_PATH
);
205 argv_array_push(out
, "sh");
207 argv_array_push(out
, "-c");
210 * If we have no extra arguments, we do not even need to
211 * bother with the "$@" magic.
214 argv_array_push(out
, argv
[0]);
216 argv_array_pushf(out
, "%s \"$@\"", argv
[0]);
219 argv_array_pushv(out
, argv
);
223 #ifndef GIT_WINDOWS_NATIVE
224 static int child_notifier
= -1;
226 static void notify_parent(void)
229 * execvp failed. If possible, we'd like to let start_command
230 * know, so failures like ENOENT can be handled right away; but
231 * otherwise, finish_command will still report the error.
233 xwrite(child_notifier
, "", 1);
236 static void prepare_cmd(struct argv_array
*out
, const struct child_process
*cmd
)
239 die("BUG: command is empty");
242 * Add SHELL_PATH so in the event exec fails with ENOEXEC we can
243 * attempt to interpret the command with 'sh'.
245 argv_array_push(out
, SHELL_PATH
);
248 argv_array_push(out
, "git");
249 argv_array_pushv(out
, cmd
->argv
);
250 } else if (cmd
->use_shell
) {
251 prepare_shell_cmd(out
, cmd
->argv
);
253 argv_array_pushv(out
, cmd
->argv
);
257 * If there are no '/' characters in the command then perform a path
258 * lookup and use the resolved path as the command to exec. If there
259 * are no '/' characters or if the command wasn't found in the path,
260 * have exec attempt to invoke the command directly.
262 if (!strchr(out
->argv
[1], '/')) {
263 char *program
= locate_in_PATH(out
->argv
[1]);
265 free((char *)out
->argv
[1]);
266 out
->argv
[1] = program
;
271 static char **prep_childenv(const char *const *deltaenv
)
273 extern char **environ
;
275 struct string_list env
= STRING_LIST_INIT_DUP
;
276 struct strbuf key
= STRBUF_INIT
;
277 const char *const *p
;
280 /* Construct a sorted string list consisting of the current environ */
281 for (p
= (const char *const *) environ
; p
&& *p
; p
++) {
282 const char *equals
= strchr(*p
, '=');
286 strbuf_add(&key
, *p
, equals
- *p
);
287 string_list_append(&env
, key
.buf
)->util
= (void *) *p
;
289 string_list_append(&env
, *p
)->util
= (void *) *p
;
292 string_list_sort(&env
);
294 /* Merge in 'deltaenv' with the current environ */
295 for (p
= deltaenv
; p
&& *p
; p
++) {
296 const char *equals
= strchr(*p
, '=');
299 /* ('key=value'), insert or replace entry */
301 strbuf_add(&key
, *p
, equals
- *p
);
302 string_list_insert(&env
, key
.buf
)->util
= (void *) *p
;
304 /* otherwise ('key') remove existing entry */
305 string_list_remove(&env
, *p
, 0);
309 /* Create an array of 'char *' to be used as the childenv */
310 childenv
= xmalloc((env
.nr
+ 1) * sizeof(char *));
311 for (i
= 0; i
< env
.nr
; i
++)
312 childenv
[i
] = env
.items
[i
].util
;
313 childenv
[env
.nr
] = NULL
;
315 string_list_clear(&env
, 0);
316 strbuf_release(&key
);
321 static inline void set_cloexec(int fd
)
323 int flags
= fcntl(fd
, F_GETFD
);
325 fcntl(fd
, F_SETFD
, flags
| FD_CLOEXEC
);
328 static int wait_or_whine(pid_t pid
, const char *argv0
, int in_signal
)
330 int status
, code
= -1;
332 int failed_errno
= 0;
334 while ((waiting
= waitpid(pid
, &status
, 0)) < 0 && errno
== EINTR
)
340 failed_errno
= errno
;
341 error_errno("waitpid for %s failed", argv0
);
342 } else if (waiting
!= pid
) {
343 error("waitpid is confused (%s)", argv0
);
344 } else if (WIFSIGNALED(status
)) {
345 code
= WTERMSIG(status
);
346 if (code
!= SIGINT
&& code
!= SIGQUIT
&& code
!= SIGPIPE
)
347 error("%s died of signal %d", argv0
, code
);
349 * This return value is chosen so that code & 0xff
350 * mimics the exit code that a POSIX shell would report for
351 * a program that died from this signal.
354 } else if (WIFEXITED(status
)) {
355 code
= WEXITSTATUS(status
);
357 * Convert special exit code when execvp failed.
361 failed_errno
= ENOENT
;
364 error("waitpid is confused (%s)", argv0
);
367 clear_child_for_cleanup(pid
);
369 errno
= failed_errno
;
373 int start_command(struct child_process
*cmd
)
375 int need_in
, need_out
, need_err
;
376 int fdin
[2], fdout
[2], fderr
[2];
381 cmd
->argv
= cmd
->args
.argv
;
383 cmd
->env
= cmd
->env_array
.argv
;
386 * In case of errors we must keep the promise to close FDs
387 * that have been passed in via ->in and ->out.
390 need_in
= !cmd
->no_stdin
&& cmd
->in
< 0;
392 if (pipe(fdin
) < 0) {
393 failed_errno
= errno
;
396 str
= "standard input";
402 need_out
= !cmd
->no_stdout
403 && !cmd
->stdout_to_stderr
406 if (pipe(fdout
) < 0) {
407 failed_errno
= errno
;
412 str
= "standard output";
418 need_err
= !cmd
->no_stderr
&& cmd
->err
< 0;
420 if (pipe(fderr
) < 0) {
421 failed_errno
= errno
;
430 str
= "standard error";
432 error("cannot create %s pipe for %s: %s",
433 str
, cmd
->argv
[0], strerror(failed_errno
));
434 child_process_clear(cmd
);
435 errno
= failed_errno
;
441 trace_argv_printf(cmd
->argv
, "trace: run_command:");
444 #ifndef GIT_WINDOWS_NATIVE
448 struct argv_array argv
= ARGV_ARRAY_INIT
;
450 if (pipe(notify_pipe
))
451 notify_pipe
[0] = notify_pipe
[1] = -1;
453 prepare_cmd(&argv
, cmd
);
454 childenv
= prep_childenv(cmd
->env
);
457 failed_errno
= errno
;
460 * Redirect the channel to write syscall error messages to
461 * before redirecting the process's stderr so that all die()
462 * in subsequent call paths use the parent's stderr.
464 if (cmd
->no_stderr
|| need_err
) {
465 int child_err
= dup(2);
466 set_cloexec(child_err
);
467 set_error_handle(fdopen(child_err
, "w"));
470 close(notify_pipe
[0]);
471 set_cloexec(notify_pipe
[1]);
472 child_notifier
= notify_pipe
[1];
473 atexit(notify_parent
);
480 } else if (cmd
->in
) {
490 } else if (cmd
->err
> 1) {
497 else if (cmd
->stdout_to_stderr
)
502 } else if (cmd
->out
> 1) {
507 if (cmd
->dir
&& chdir(cmd
->dir
))
508 die_errno("exec '%s': cd to '%s' failed", cmd
->argv
[0],
512 * Attempt to exec using the command and arguments starting at
513 * argv.argv[1]. argv.argv[0] contains SHELL_PATH which will
514 * be used in the event exec failed with ENOEXEC at which point
515 * we will try to interpret the command using 'sh'.
517 execve(argv
.argv
[1], (char *const *) argv
.argv
+ 1,
518 (char *const *) childenv
);
519 if (errno
== ENOEXEC
)
520 execve(argv
.argv
[0], (char *const *) argv
.argv
,
521 (char *const *) childenv
);
523 if (errno
== ENOENT
) {
524 if (!cmd
->silent_exec_failure
)
525 error("cannot run %s: %s", cmd
->argv
[0],
529 die_errno("cannot exec '%s'", cmd
->argv
[0]);
533 error_errno("cannot fork() for %s", cmd
->argv
[0]);
534 else if (cmd
->clean_on_exit
)
535 mark_child_for_cleanup(cmd
->pid
, cmd
);
538 * Wait for child's exec. If the exec succeeds (or if fork()
539 * failed), EOF is seen immediately by the parent. Otherwise, the
540 * child process sends a single byte.
541 * Note that use of this infrastructure is completely advisory,
542 * therefore, we keep error checks minimal.
544 close(notify_pipe
[1]);
545 if (read(notify_pipe
[0], ¬ify_pipe
[1], 1) == 1) {
547 * At this point we know that fork() succeeded, but exec()
548 * failed. Errors have been reported to our stderr.
550 wait_or_whine(cmd
->pid
, cmd
->argv
[0], 0);
551 failed_errno
= errno
;
554 close(notify_pipe
[0]);
556 argv_array_clear(&argv
);
561 int fhin
= 0, fhout
= 1, fherr
= 2;
562 const char **sargv
= cmd
->argv
;
563 struct argv_array nargv
= ARGV_ARRAY_INIT
;
566 fhin
= open("/dev/null", O_RDWR
);
573 fherr
= open("/dev/null", O_RDWR
);
575 fherr
= dup(fderr
[1]);
576 else if (cmd
->err
> 2)
577 fherr
= dup(cmd
->err
);
580 fhout
= open("/dev/null", O_RDWR
);
581 else if (cmd
->stdout_to_stderr
)
584 fhout
= dup(fdout
[1]);
585 else if (cmd
->out
> 1)
586 fhout
= dup(cmd
->out
);
589 cmd
->argv
= prepare_git_cmd(&nargv
, cmd
->argv
);
590 else if (cmd
->use_shell
)
591 cmd
->argv
= prepare_shell_cmd(&nargv
, cmd
->argv
);
593 cmd
->pid
= mingw_spawnvpe(cmd
->argv
[0], cmd
->argv
, (char**) cmd
->env
,
594 cmd
->dir
, fhin
, fhout
, fherr
);
595 failed_errno
= errno
;
596 if (cmd
->pid
< 0 && (!cmd
->silent_exec_failure
|| errno
!= ENOENT
))
597 error_errno("cannot spawn %s", cmd
->argv
[0]);
598 if (cmd
->clean_on_exit
&& cmd
->pid
>= 0)
599 mark_child_for_cleanup(cmd
->pid
, cmd
);
601 argv_array_clear(&nargv
);
625 child_process_clear(cmd
);
626 errno
= failed_errno
;
648 int finish_command(struct child_process
*cmd
)
650 int ret
= wait_or_whine(cmd
->pid
, cmd
->argv
[0], 0);
651 child_process_clear(cmd
);
655 int finish_command_in_signal(struct child_process
*cmd
)
657 return wait_or_whine(cmd
->pid
, cmd
->argv
[0], 1);
661 int run_command(struct child_process
*cmd
)
665 if (cmd
->out
< 0 || cmd
->err
< 0)
666 die("BUG: run_command with a pipe can cause deadlock");
668 code
= start_command(cmd
);
671 return finish_command(cmd
);
674 int run_command_v_opt(const char **argv
, int opt
)
676 return run_command_v_opt_cd_env(argv
, opt
, NULL
, NULL
);
679 int run_command_v_opt_cd_env(const char **argv
, int opt
, const char *dir
, const char *const *env
)
681 struct child_process cmd
= CHILD_PROCESS_INIT
;
683 cmd
.no_stdin
= opt
& RUN_COMMAND_NO_STDIN
? 1 : 0;
684 cmd
.git_cmd
= opt
& RUN_GIT_CMD
? 1 : 0;
685 cmd
.stdout_to_stderr
= opt
& RUN_COMMAND_STDOUT_TO_STDERR
? 1 : 0;
686 cmd
.silent_exec_failure
= opt
& RUN_SILENT_EXEC_FAILURE
? 1 : 0;
687 cmd
.use_shell
= opt
& RUN_USING_SHELL
? 1 : 0;
688 cmd
.clean_on_exit
= opt
& RUN_CLEAN_ON_EXIT
? 1 : 0;
691 return run_command(&cmd
);
695 static pthread_t main_thread
;
696 static int main_thread_set
;
697 static pthread_key_t async_key
;
698 static pthread_key_t async_die_counter
;
700 static void *run_thread(void *data
)
702 struct async
*async
= data
;
705 if (async
->isolate_sigpipe
) {
708 sigaddset(&mask
, SIGPIPE
);
709 if (pthread_sigmask(SIG_BLOCK
, &mask
, NULL
) < 0) {
710 ret
= error("unable to block SIGPIPE in async thread");
715 pthread_setspecific(async_key
, async
);
716 ret
= async
->proc(async
->proc_in
, async
->proc_out
, async
->data
);
720 static NORETURN
void die_async(const char *err
, va_list params
)
722 vreportf("fatal: ", err
, params
);
725 struct async
*async
= pthread_getspecific(async_key
);
726 if (async
->proc_in
>= 0)
727 close(async
->proc_in
);
728 if (async
->proc_out
>= 0)
729 close(async
->proc_out
);
730 pthread_exit((void *)128);
736 static int async_die_is_recursing(void)
738 void *ret
= pthread_getspecific(async_die_counter
);
739 pthread_setspecific(async_die_counter
, (void *)1);
745 if (!main_thread_set
)
746 return 0; /* no asyncs started yet */
747 return !pthread_equal(main_thread
, pthread_self());
750 static void NORETURN
async_exit(int code
)
752 pthread_exit((void *)(intptr_t)code
);
758 void (**handlers
)(void);
763 static int git_atexit_installed
;
765 static void git_atexit_dispatch(void)
769 for (i
=git_atexit_hdlrs
.nr
; i
; i
--)
770 git_atexit_hdlrs
.handlers
[i
-1]();
773 static void git_atexit_clear(void)
775 free(git_atexit_hdlrs
.handlers
);
776 memset(&git_atexit_hdlrs
, 0, sizeof(git_atexit_hdlrs
));
777 git_atexit_installed
= 0;
781 int git_atexit(void (*handler
)(void))
783 ALLOC_GROW(git_atexit_hdlrs
.handlers
, git_atexit_hdlrs
.nr
+ 1, git_atexit_hdlrs
.alloc
);
784 git_atexit_hdlrs
.handlers
[git_atexit_hdlrs
.nr
++] = handler
;
785 if (!git_atexit_installed
) {
786 if (atexit(&git_atexit_dispatch
))
788 git_atexit_installed
= 1;
792 #define atexit git_atexit
794 static int process_is_async
;
797 return process_is_async
;
800 static void NORETURN
async_exit(int code
)
807 void check_pipe(int err
)
813 signal(SIGPIPE
, SIG_DFL
);
815 /* Should never happen, but just in case... */
820 int start_async(struct async
*async
)
822 int need_in
, need_out
;
823 int fdin
[2], fdout
[2];
824 int proc_in
, proc_out
;
826 need_in
= async
->in
< 0;
828 if (pipe(fdin
) < 0) {
831 return error_errno("cannot create pipe");
836 need_out
= async
->out
< 0;
838 if (pipe(fdout
) < 0) {
843 return error_errno("cannot create pipe");
845 async
->out
= fdout
[0];
858 proc_out
= async
->out
;
863 /* Flush stdio before fork() to avoid cloning buffers */
867 if (async
->pid
< 0) {
868 error_errno("fork (async) failed");
877 process_is_async
= 1;
878 exit(!!async
->proc(proc_in
, proc_out
, async
->data
));
881 mark_child_for_cleanup(async
->pid
, NULL
);
893 if (!main_thread_set
) {
895 * We assume that the first time that start_async is called
896 * it is from the main thread.
899 main_thread
= pthread_self();
900 pthread_key_create(&async_key
, NULL
);
901 pthread_key_create(&async_die_counter
, NULL
);
902 set_die_routine(die_async
);
903 set_die_is_recursing_routine(async_die_is_recursing
);
907 set_cloexec(proc_in
);
909 set_cloexec(proc_out
);
910 async
->proc_in
= proc_in
;
911 async
->proc_out
= proc_out
;
913 int err
= pthread_create(&async
->tid
, NULL
, run_thread
, async
);
915 error_errno("cannot create thread");
935 int finish_async(struct async
*async
)
938 return wait_or_whine(async
->pid
, "child process", 0);
940 void *ret
= (void *)(intptr_t)(-1);
942 if (pthread_join(async
->tid
, &ret
))
943 error("pthread_join failed");
944 return (int)(intptr_t)ret
;
948 const char *find_hook(const char *name
)
950 static struct strbuf path
= STRBUF_INIT
;
953 strbuf_git_path(&path
, "hooks/%s", name
);
954 if (access(path
.buf
, X_OK
) < 0) {
955 #ifdef STRIP_EXTENSION
956 strbuf_addstr(&path
, STRIP_EXTENSION
);
957 if (access(path
.buf
, X_OK
) >= 0)
965 int run_hook_ve(const char *const *env
, const char *name
, va_list args
)
967 struct child_process hook
= CHILD_PROCESS_INIT
;
974 argv_array_push(&hook
.args
, p
);
975 while ((p
= va_arg(args
, const char *)))
976 argv_array_push(&hook
.args
, p
);
979 hook
.stdout_to_stderr
= 1;
981 return run_command(&hook
);
984 int run_hook_le(const char *const *env
, const char *name
, ...)
989 va_start(args
, name
);
990 ret
= run_hook_ve(env
, name
, args
);
997 /* initialized by caller */
999 int type
; /* POLLOUT or POLLIN */
1011 /* returned by pump_io */
1012 int error
; /* 0 for success, otherwise errno */
1018 static int pump_io_round(struct io_pump
*slots
, int nr
, struct pollfd
*pfd
)
1023 for (i
= 0; i
< nr
; i
++) {
1024 struct io_pump
*io
= &slots
[i
];
1027 pfd
[pollsize
].fd
= io
->fd
;
1028 pfd
[pollsize
].events
= io
->type
;
1029 io
->pfd
= &pfd
[pollsize
++];
1035 if (poll(pfd
, pollsize
, -1) < 0) {
1038 die_errno("poll failed");
1041 for (i
= 0; i
< nr
; i
++) {
1042 struct io_pump
*io
= &slots
[i
];
1047 if (!(io
->pfd
->revents
& (POLLOUT
|POLLIN
|POLLHUP
|POLLERR
|POLLNVAL
)))
1050 if (io
->type
== POLLOUT
) {
1051 ssize_t len
= xwrite(io
->fd
,
1052 io
->u
.out
.buf
, io
->u
.out
.len
);
1058 io
->u
.out
.buf
+= len
;
1059 io
->u
.out
.len
-= len
;
1060 if (!io
->u
.out
.len
) {
1067 if (io
->type
== POLLIN
) {
1068 ssize_t len
= strbuf_read_once(io
->u
.in
.buf
,
1069 io
->fd
, io
->u
.in
.hint
);
1082 static int pump_io(struct io_pump
*slots
, int nr
)
1087 for (i
= 0; i
< nr
; i
++)
1090 ALLOC_ARRAY(pfd
, nr
);
1091 while (pump_io_round(slots
, nr
, pfd
))
1095 /* There may be multiple errno values, so just pick the first. */
1096 for (i
= 0; i
< nr
; i
++) {
1097 if (slots
[i
].error
) {
1098 errno
= slots
[i
].error
;
1106 int pipe_command(struct child_process
*cmd
,
1107 const char *in
, size_t in_len
,
1108 struct strbuf
*out
, size_t out_hint
,
1109 struct strbuf
*err
, size_t err_hint
)
1111 struct io_pump io
[3];
1121 if (start_command(cmd
) < 0)
1125 io
[nr
].fd
= cmd
->in
;
1126 io
[nr
].type
= POLLOUT
;
1127 io
[nr
].u
.out
.buf
= in
;
1128 io
[nr
].u
.out
.len
= in_len
;
1132 io
[nr
].fd
= cmd
->out
;
1133 io
[nr
].type
= POLLIN
;
1134 io
[nr
].u
.in
.buf
= out
;
1135 io
[nr
].u
.in
.hint
= out_hint
;
1139 io
[nr
].fd
= cmd
->err
;
1140 io
[nr
].type
= POLLIN
;
1141 io
[nr
].u
.in
.buf
= err
;
1142 io
[nr
].u
.in
.hint
= err_hint
;
1146 if (pump_io(io
, nr
) < 0) {
1147 finish_command(cmd
); /* throw away exit code */
1151 return finish_command(cmd
);
1157 GIT_CP_WAIT_CLEANUP
,
1160 struct parallel_processes
{
1166 get_next_task_fn get_next_task
;
1167 start_failure_fn start_failure
;
1168 task_finished_fn task_finished
;
1171 enum child_state state
;
1172 struct child_process process
;
1177 * The struct pollfd is logically part of *children,
1178 * but the system call expects it as its own array.
1182 unsigned shutdown
: 1;
1185 struct strbuf buffered_output
; /* of finished children */
1188 static int default_start_failure(struct strbuf
*out
,
1195 static int default_task_finished(int result
,
1203 static void kill_children(struct parallel_processes
*pp
, int signo
)
1205 int i
, n
= pp
->max_processes
;
1207 for (i
= 0; i
< n
; i
++)
1208 if (pp
->children
[i
].state
== GIT_CP_WORKING
)
1209 kill(pp
->children
[i
].process
.pid
, signo
);
1212 static struct parallel_processes
*pp_for_signal
;
1214 static void handle_children_on_signal(int signo
)
1216 kill_children(pp_for_signal
, signo
);
1217 sigchain_pop(signo
);
1221 static void pp_init(struct parallel_processes
*pp
,
1223 get_next_task_fn get_next_task
,
1224 start_failure_fn start_failure
,
1225 task_finished_fn task_finished
,
1233 pp
->max_processes
= n
;
1235 trace_printf("run_processes_parallel: preparing to run up to %d tasks", n
);
1239 die("BUG: you need to specify a get_next_task function");
1240 pp
->get_next_task
= get_next_task
;
1242 pp
->start_failure
= start_failure
? start_failure
: default_start_failure
;
1243 pp
->task_finished
= task_finished
? task_finished
: default_task_finished
;
1245 pp
->nr_processes
= 0;
1246 pp
->output_owner
= 0;
1248 pp
->children
= xcalloc(n
, sizeof(*pp
->children
));
1249 pp
->pfd
= xcalloc(n
, sizeof(*pp
->pfd
));
1250 strbuf_init(&pp
->buffered_output
, 0);
1252 for (i
= 0; i
< n
; i
++) {
1253 strbuf_init(&pp
->children
[i
].err
, 0);
1254 child_process_init(&pp
->children
[i
].process
);
1255 pp
->pfd
[i
].events
= POLLIN
| POLLHUP
;
1260 sigchain_push_common(handle_children_on_signal
);
1263 static void pp_cleanup(struct parallel_processes
*pp
)
1267 trace_printf("run_processes_parallel: done");
1268 for (i
= 0; i
< pp
->max_processes
; i
++) {
1269 strbuf_release(&pp
->children
[i
].err
);
1270 child_process_clear(&pp
->children
[i
].process
);
1277 * When get_next_task added messages to the buffer in its last
1278 * iteration, the buffered output is non empty.
1280 strbuf_write(&pp
->buffered_output
, stderr
);
1281 strbuf_release(&pp
->buffered_output
);
1283 sigchain_pop_common();
1287 * 0 if a new task was started.
1288 * 1 if no new jobs was started (get_next_task ran out of work, non critical
1289 * problem with starting a new command)
1290 * <0 no new job was started, user wishes to shutdown early. Use negative code
1291 * to signal the children.
1293 static int pp_start_one(struct parallel_processes
*pp
)
1297 for (i
= 0; i
< pp
->max_processes
; i
++)
1298 if (pp
->children
[i
].state
== GIT_CP_FREE
)
1300 if (i
== pp
->max_processes
)
1301 die("BUG: bookkeeping is hard");
1303 code
= pp
->get_next_task(&pp
->children
[i
].process
,
1304 &pp
->children
[i
].err
,
1306 &pp
->children
[i
].data
);
1308 strbuf_addbuf(&pp
->buffered_output
, &pp
->children
[i
].err
);
1309 strbuf_reset(&pp
->children
[i
].err
);
1312 pp
->children
[i
].process
.err
= -1;
1313 pp
->children
[i
].process
.stdout_to_stderr
= 1;
1314 pp
->children
[i
].process
.no_stdin
= 1;
1316 if (start_command(&pp
->children
[i
].process
)) {
1317 code
= pp
->start_failure(&pp
->children
[i
].err
,
1319 &pp
->children
[i
].data
);
1320 strbuf_addbuf(&pp
->buffered_output
, &pp
->children
[i
].err
);
1321 strbuf_reset(&pp
->children
[i
].err
);
1328 pp
->children
[i
].state
= GIT_CP_WORKING
;
1329 pp
->pfd
[i
].fd
= pp
->children
[i
].process
.err
;
1333 static void pp_buffer_stderr(struct parallel_processes
*pp
, int output_timeout
)
1337 while ((i
= poll(pp
->pfd
, pp
->max_processes
, output_timeout
)) < 0) {
1344 /* Buffer output from all pipes. */
1345 for (i
= 0; i
< pp
->max_processes
; i
++) {
1346 if (pp
->children
[i
].state
== GIT_CP_WORKING
&&
1347 pp
->pfd
[i
].revents
& (POLLIN
| POLLHUP
)) {
1348 int n
= strbuf_read_once(&pp
->children
[i
].err
,
1349 pp
->children
[i
].process
.err
, 0);
1351 close(pp
->children
[i
].process
.err
);
1352 pp
->children
[i
].state
= GIT_CP_WAIT_CLEANUP
;
1354 if (errno
!= EAGAIN
)
1360 static void pp_output(struct parallel_processes
*pp
)
1362 int i
= pp
->output_owner
;
1363 if (pp
->children
[i
].state
== GIT_CP_WORKING
&&
1364 pp
->children
[i
].err
.len
) {
1365 strbuf_write(&pp
->children
[i
].err
, stderr
);
1366 strbuf_reset(&pp
->children
[i
].err
);
1370 static int pp_collect_finished(struct parallel_processes
*pp
)
1373 int n
= pp
->max_processes
;
1376 while (pp
->nr_processes
> 0) {
1377 for (i
= 0; i
< pp
->max_processes
; i
++)
1378 if (pp
->children
[i
].state
== GIT_CP_WAIT_CLEANUP
)
1380 if (i
== pp
->max_processes
)
1383 code
= finish_command(&pp
->children
[i
].process
);
1385 code
= pp
->task_finished(code
,
1386 &pp
->children
[i
].err
, pp
->data
,
1387 &pp
->children
[i
].data
);
1395 pp
->children
[i
].state
= GIT_CP_FREE
;
1397 child_process_init(&pp
->children
[i
].process
);
1399 if (i
!= pp
->output_owner
) {
1400 strbuf_addbuf(&pp
->buffered_output
, &pp
->children
[i
].err
);
1401 strbuf_reset(&pp
->children
[i
].err
);
1403 strbuf_write(&pp
->children
[i
].err
, stderr
);
1404 strbuf_reset(&pp
->children
[i
].err
);
1406 /* Output all other finished child processes */
1407 strbuf_write(&pp
->buffered_output
, stderr
);
1408 strbuf_reset(&pp
->buffered_output
);
1411 * Pick next process to output live.
1413 * For now we pick it randomly by doing a round
1414 * robin. Later we may want to pick the one with
1415 * the most output or the longest or shortest
1416 * running process time.
1418 for (i
= 0; i
< n
; i
++)
1419 if (pp
->children
[(pp
->output_owner
+ i
) % n
].state
== GIT_CP_WORKING
)
1421 pp
->output_owner
= (pp
->output_owner
+ i
) % n
;
1427 int run_processes_parallel(int n
,
1428 get_next_task_fn get_next_task
,
1429 start_failure_fn start_failure
,
1430 task_finished_fn task_finished
,
1434 int output_timeout
= 100;
1436 struct parallel_processes pp
;
1438 pp_init(&pp
, n
, get_next_task
, start_failure
, task_finished
, pp_cb
);
1441 i
< spawn_cap
&& !pp
.shutdown
&&
1442 pp
.nr_processes
< pp
.max_processes
;
1444 code
= pp_start_one(&pp
);
1449 kill_children(&pp
, -code
);
1453 if (!pp
.nr_processes
)
1455 pp_buffer_stderr(&pp
, output_timeout
);
1457 code
= pp_collect_finished(&pp
);
1461 kill_children(&pp
, -code
);