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1 | #include "cache.h" | |
2 | #include "run-command.h" | |
3 | #include "exec_cmd.h" | |
4 | #include "sigchain.h" | |
5 | #include "argv-array.h" | |
6 | #include "thread-utils.h" | |
7 | #include "strbuf.h" | |
8 | #include "string-list.h" | |
9 | #include "quote.h" | |
10 | ||
11 | void child_process_init(struct child_process *child) | |
12 | { | |
13 | memset(child, 0, sizeof(*child)); | |
14 | argv_array_init(&child->args); | |
15 | argv_array_init(&child->env_array); | |
16 | } | |
17 | ||
18 | void child_process_clear(struct child_process *child) | |
19 | { | |
20 | argv_array_clear(&child->args); | |
21 | argv_array_clear(&child->env_array); | |
22 | } | |
23 | ||
24 | struct child_to_clean { | |
25 | pid_t pid; | |
26 | struct child_process *process; | |
27 | struct child_to_clean *next; | |
28 | }; | |
29 | static struct child_to_clean *children_to_clean; | |
30 | static int installed_child_cleanup_handler; | |
31 | ||
32 | static void cleanup_children(int sig, int in_signal) | |
33 | { | |
34 | struct child_to_clean *children_to_wait_for = NULL; | |
35 | ||
36 | while (children_to_clean) { | |
37 | struct child_to_clean *p = children_to_clean; | |
38 | children_to_clean = p->next; | |
39 | ||
40 | if (p->process && !in_signal) { | |
41 | struct child_process *process = p->process; | |
42 | if (process->clean_on_exit_handler) { | |
43 | trace_printf( | |
44 | "trace: run_command: running exit handler for pid %" | |
45 | PRIuMAX, (uintmax_t)p->pid | |
46 | ); | |
47 | process->clean_on_exit_handler(process); | |
48 | } | |
49 | } | |
50 | ||
51 | kill(p->pid, sig); | |
52 | ||
53 | if (p->process && p->process->wait_after_clean) { | |
54 | p->next = children_to_wait_for; | |
55 | children_to_wait_for = p; | |
56 | } else { | |
57 | if (!in_signal) | |
58 | free(p); | |
59 | } | |
60 | } | |
61 | ||
62 | while (children_to_wait_for) { | |
63 | struct child_to_clean *p = children_to_wait_for; | |
64 | children_to_wait_for = p->next; | |
65 | ||
66 | while (waitpid(p->pid, NULL, 0) < 0 && errno == EINTR) | |
67 | ; /* spin waiting for process exit or error */ | |
68 | ||
69 | if (!in_signal) | |
70 | free(p); | |
71 | } | |
72 | } | |
73 | ||
74 | static void cleanup_children_on_signal(int sig) | |
75 | { | |
76 | cleanup_children(sig, 1); | |
77 | sigchain_pop(sig); | |
78 | raise(sig); | |
79 | } | |
80 | ||
81 | static void cleanup_children_on_exit(void) | |
82 | { | |
83 | cleanup_children(SIGTERM, 0); | |
84 | } | |
85 | ||
86 | static void mark_child_for_cleanup(pid_t pid, struct child_process *process) | |
87 | { | |
88 | struct child_to_clean *p = xmalloc(sizeof(*p)); | |
89 | p->pid = pid; | |
90 | p->process = process; | |
91 | p->next = children_to_clean; | |
92 | children_to_clean = p; | |
93 | ||
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; | |
98 | } | |
99 | } | |
100 | ||
101 | static void clear_child_for_cleanup(pid_t pid) | |
102 | { | |
103 | struct child_to_clean **pp; | |
104 | ||
105 | for (pp = &children_to_clean; *pp; pp = &(*pp)->next) { | |
106 | struct child_to_clean *clean_me = *pp; | |
107 | ||
108 | if (clean_me->pid == pid) { | |
109 | *pp = clean_me->next; | |
110 | free(clean_me); | |
111 | return; | |
112 | } | |
113 | } | |
114 | } | |
115 | ||
116 | static inline void close_pair(int fd[2]) | |
117 | { | |
118 | close(fd[0]); | |
119 | close(fd[1]); | |
120 | } | |
121 | ||
122 | int is_executable(const char *name) | |
123 | { | |
124 | struct stat st; | |
125 | ||
126 | if (stat(name, &st) || /* stat, not lstat */ | |
127 | !S_ISREG(st.st_mode)) | |
128 | return 0; | |
129 | ||
130 | #if defined(GIT_WINDOWS_NATIVE) | |
131 | /* | |
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. | |
138 | */ | |
139 | if (ends_with(name, ".exe")) | |
140 | return S_IXUSR; | |
141 | ||
142 | { | |
143 | /* | |
144 | * Now that we know it does not have an executable extension, | |
145 | * peek into the file instead. | |
146 | */ | |
147 | char buf[3] = { 0 }; | |
148 | int n; | |
149 | int fd = open(name, O_RDONLY); | |
150 | st.st_mode &= ~S_IXUSR; | |
151 | if (fd >= 0) { | |
152 | n = read(fd, buf, 2); | |
153 | if (n == 2) | |
154 | /* look for a she-bang */ | |
155 | if (!strcmp(buf, "#!")) | |
156 | st.st_mode |= S_IXUSR; | |
157 | close(fd); | |
158 | } | |
159 | } | |
160 | #endif | |
161 | return st.st_mode & S_IXUSR; | |
162 | } | |
163 | ||
164 | /* | |
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. | |
169 | * | |
170 | * The caller should ensure that file contains no directory | |
171 | * separators. | |
172 | * | |
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. | |
176 | * | |
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 | |
179 | * "foo.exe"). | |
180 | */ | |
181 | static char *locate_in_PATH(const char *file) | |
182 | { | |
183 | const char *p = getenv("PATH"); | |
184 | struct strbuf buf = STRBUF_INIT; | |
185 | ||
186 | if (!p || !*p) | |
187 | return NULL; | |
188 | ||
189 | while (1) { | |
190 | const char *end = strchrnul(p, ':'); | |
191 | ||
192 | strbuf_reset(&buf); | |
193 | ||
194 | /* POSIX specifies an empty entry as the current directory. */ | |
195 | if (end != p) { | |
196 | strbuf_add(&buf, p, end - p); | |
197 | strbuf_addch(&buf, '/'); | |
198 | } | |
199 | strbuf_addstr(&buf, file); | |
200 | ||
201 | if (is_executable(buf.buf)) | |
202 | return strbuf_detach(&buf, NULL); | |
203 | ||
204 | if (!*end) | |
205 | break; | |
206 | p = end + 1; | |
207 | } | |
208 | ||
209 | strbuf_release(&buf); | |
210 | return NULL; | |
211 | } | |
212 | ||
213 | static int exists_in_PATH(const char *file) | |
214 | { | |
215 | char *r = locate_in_PATH(file); | |
216 | free(r); | |
217 | return r != NULL; | |
218 | } | |
219 | ||
220 | int sane_execvp(const char *file, char * const argv[]) | |
221 | { | |
222 | if (!execvp(file, argv)) | |
223 | return 0; /* cannot happen ;-) */ | |
224 | ||
225 | /* | |
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 | |
230 | * intuitive. | |
231 | * | |
232 | * We avoid commands with "/", because execvp will not do $PATH | |
233 | * lookups in that case. | |
234 | * | |
235 | * The reassignment of EACCES to errno looks like a no-op below, | |
236 | * but we need to protect against exists_in_PATH overwriting errno. | |
237 | */ | |
238 | if (errno == EACCES && !strchr(file, '/')) | |
239 | errno = exists_in_PATH(file) ? EACCES : ENOENT; | |
240 | else if (errno == ENOTDIR && !strchr(file, '/')) | |
241 | errno = ENOENT; | |
242 | return -1; | |
243 | } | |
244 | ||
245 | static const char **prepare_shell_cmd(struct argv_array *out, const char **argv) | |
246 | { | |
247 | if (!argv[0]) | |
248 | die("BUG: shell command is empty"); | |
249 | ||
250 | if (strcspn(argv[0], "|&;<>()$`\\\"' \t\n*?[#~=%") != strlen(argv[0])) { | |
251 | #ifndef GIT_WINDOWS_NATIVE | |
252 | argv_array_push(out, SHELL_PATH); | |
253 | #else | |
254 | argv_array_push(out, "sh"); | |
255 | #endif | |
256 | argv_array_push(out, "-c"); | |
257 | ||
258 | /* | |
259 | * If we have no extra arguments, we do not even need to | |
260 | * bother with the "$@" magic. | |
261 | */ | |
262 | if (!argv[1]) | |
263 | argv_array_push(out, argv[0]); | |
264 | else | |
265 | argv_array_pushf(out, "%s \"$@\"", argv[0]); | |
266 | } | |
267 | ||
268 | argv_array_pushv(out, argv); | |
269 | return out->argv; | |
270 | } | |
271 | ||
272 | #ifndef GIT_WINDOWS_NATIVE | |
273 | static int child_notifier = -1; | |
274 | ||
275 | enum child_errcode { | |
276 | CHILD_ERR_CHDIR, | |
277 | CHILD_ERR_DUP2, | |
278 | CHILD_ERR_CLOSE, | |
279 | CHILD_ERR_SIGPROCMASK, | |
280 | CHILD_ERR_ENOENT, | |
281 | CHILD_ERR_SILENT, | |
282 | CHILD_ERR_ERRNO | |
283 | }; | |
284 | ||
285 | struct child_err { | |
286 | enum child_errcode err; | |
287 | int syserr; /* errno */ | |
288 | }; | |
289 | ||
290 | static void child_die(enum child_errcode err) | |
291 | { | |
292 | struct child_err buf; | |
293 | ||
294 | buf.err = err; | |
295 | buf.syserr = errno; | |
296 | ||
297 | /* write(2) on buf smaller than PIPE_BUF (min 512) is atomic: */ | |
298 | xwrite(child_notifier, &buf, sizeof(buf)); | |
299 | _exit(1); | |
300 | } | |
301 | ||
302 | static void child_dup2(int fd, int to) | |
303 | { | |
304 | if (dup2(fd, to) < 0) | |
305 | child_die(CHILD_ERR_DUP2); | |
306 | } | |
307 | ||
308 | static void child_close(int fd) | |
309 | { | |
310 | if (close(fd)) | |
311 | child_die(CHILD_ERR_CLOSE); | |
312 | } | |
313 | ||
314 | static void child_close_pair(int fd[2]) | |
315 | { | |
316 | child_close(fd[0]); | |
317 | child_close(fd[1]); | |
318 | } | |
319 | ||
320 | /* | |
321 | * parent will make it look like the child spewed a fatal error and died | |
322 | * this is needed to prevent changes to t0061. | |
323 | */ | |
324 | static void fake_fatal(const char *err, va_list params) | |
325 | { | |
326 | vreportf("fatal: ", err, params); | |
327 | } | |
328 | ||
329 | static void child_error_fn(const char *err, va_list params) | |
330 | { | |
331 | const char msg[] = "error() should not be called in child\n"; | |
332 | xwrite(2, msg, sizeof(msg) - 1); | |
333 | } | |
334 | ||
335 | static void child_warn_fn(const char *err, va_list params) | |
336 | { | |
337 | const char msg[] = "warn() should not be called in child\n"; | |
338 | xwrite(2, msg, sizeof(msg) - 1); | |
339 | } | |
340 | ||
341 | static void NORETURN child_die_fn(const char *err, va_list params) | |
342 | { | |
343 | const char msg[] = "die() should not be called in child\n"; | |
344 | xwrite(2, msg, sizeof(msg) - 1); | |
345 | _exit(2); | |
346 | } | |
347 | ||
348 | /* this runs in the parent process */ | |
349 | static void child_err_spew(struct child_process *cmd, struct child_err *cerr) | |
350 | { | |
351 | static void (*old_errfn)(const char *err, va_list params); | |
352 | ||
353 | old_errfn = get_error_routine(); | |
354 | set_error_routine(fake_fatal); | |
355 | errno = cerr->syserr; | |
356 | ||
357 | switch (cerr->err) { | |
358 | case CHILD_ERR_CHDIR: | |
359 | error_errno("exec '%s': cd to '%s' failed", | |
360 | cmd->argv[0], cmd->dir); | |
361 | break; | |
362 | case CHILD_ERR_DUP2: | |
363 | error_errno("dup2() in child failed"); | |
364 | break; | |
365 | case CHILD_ERR_CLOSE: | |
366 | error_errno("close() in child failed"); | |
367 | break; | |
368 | case CHILD_ERR_SIGPROCMASK: | |
369 | error_errno("sigprocmask failed restoring signals"); | |
370 | break; | |
371 | case CHILD_ERR_ENOENT: | |
372 | error_errno("cannot run %s", cmd->argv[0]); | |
373 | break; | |
374 | case CHILD_ERR_SILENT: | |
375 | break; | |
376 | case CHILD_ERR_ERRNO: | |
377 | error_errno("cannot exec '%s'", cmd->argv[0]); | |
378 | break; | |
379 | } | |
380 | set_error_routine(old_errfn); | |
381 | } | |
382 | ||
383 | static void prepare_cmd(struct argv_array *out, const struct child_process *cmd) | |
384 | { | |
385 | if (!cmd->argv[0]) | |
386 | die("BUG: command is empty"); | |
387 | ||
388 | /* | |
389 | * Add SHELL_PATH so in the event exec fails with ENOEXEC we can | |
390 | * attempt to interpret the command with 'sh'. | |
391 | */ | |
392 | argv_array_push(out, SHELL_PATH); | |
393 | ||
394 | if (cmd->git_cmd) { | |
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); | |
399 | } else { | |
400 | argv_array_pushv(out, cmd->argv); | |
401 | } | |
402 | ||
403 | /* | |
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. | |
408 | */ | |
409 | if (!strchr(out->argv[1], '/')) { | |
410 | char *program = locate_in_PATH(out->argv[1]); | |
411 | if (program) { | |
412 | free((char *)out->argv[1]); | |
413 | out->argv[1] = program; | |
414 | } | |
415 | } | |
416 | } | |
417 | ||
418 | static char **prep_childenv(const char *const *deltaenv) | |
419 | { | |
420 | extern char **environ; | |
421 | char **childenv; | |
422 | struct string_list env = STRING_LIST_INIT_DUP; | |
423 | struct strbuf key = STRBUF_INIT; | |
424 | const char *const *p; | |
425 | int i; | |
426 | ||
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, '='); | |
430 | ||
431 | if (equals) { | |
432 | strbuf_reset(&key); | |
433 | strbuf_add(&key, *p, equals - *p); | |
434 | string_list_append(&env, key.buf)->util = (void *) *p; | |
435 | } else { | |
436 | string_list_append(&env, *p)->util = (void *) *p; | |
437 | } | |
438 | } | |
439 | string_list_sort(&env); | |
440 | ||
441 | /* Merge in 'deltaenv' with the current environ */ | |
442 | for (p = deltaenv; p && *p; p++) { | |
443 | const char *equals = strchr(*p, '='); | |
444 | ||
445 | if (equals) { | |
446 | /* ('key=value'), insert or replace entry */ | |
447 | strbuf_reset(&key); | |
448 | strbuf_add(&key, *p, equals - *p); | |
449 | string_list_insert(&env, key.buf)->util = (void *) *p; | |
450 | } else { | |
451 | /* otherwise ('key') remove existing entry */ | |
452 | string_list_remove(&env, *p, 0); | |
453 | } | |
454 | } | |
455 | ||
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; | |
461 | ||
462 | string_list_clear(&env, 0); | |
463 | strbuf_release(&key); | |
464 | return childenv; | |
465 | } | |
466 | ||
467 | struct atfork_state { | |
468 | #ifndef NO_PTHREADS | |
469 | int cs; | |
470 | #endif | |
471 | sigset_t old; | |
472 | }; | |
473 | ||
474 | #ifndef NO_PTHREADS | |
475 | static void bug_die(int err, const char *msg) | |
476 | { | |
477 | if (err) { | |
478 | errno = err; | |
479 | die_errno("BUG: %s", msg); | |
480 | } | |
481 | } | |
482 | #endif | |
483 | ||
484 | static void atfork_prepare(struct atfork_state *as) | |
485 | { | |
486 | sigset_t all; | |
487 | ||
488 | if (sigfillset(&all)) | |
489 | die_errno("sigfillset"); | |
490 | #ifdef NO_PTHREADS | |
491 | if (sigprocmask(SIG_SETMASK, &all, &as->old)) | |
492 | die_errno("sigprocmask"); | |
493 | #else | |
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"); | |
498 | #endif | |
499 | } | |
500 | ||
501 | static void atfork_parent(struct atfork_state *as) | |
502 | { | |
503 | #ifdef NO_PTHREADS | |
504 | if (sigprocmask(SIG_SETMASK, &as->old, NULL)) | |
505 | die_errno("sigprocmask"); | |
506 | #else | |
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"); | |
511 | #endif | |
512 | } | |
513 | #endif /* GIT_WINDOWS_NATIVE */ | |
514 | ||
515 | static inline void set_cloexec(int fd) | |
516 | { | |
517 | int flags = fcntl(fd, F_GETFD); | |
518 | if (flags >= 0) | |
519 | fcntl(fd, F_SETFD, flags | FD_CLOEXEC); | |
520 | } | |
521 | ||
522 | static int wait_or_whine(pid_t pid, const char *argv0, int in_signal) | |
523 | { | |
524 | int status, code = -1; | |
525 | pid_t waiting; | |
526 | int failed_errno = 0; | |
527 | ||
528 | while ((waiting = waitpid(pid, &status, 0)) < 0 && errno == EINTR) | |
529 | ; /* nothing */ | |
530 | if (in_signal) | |
531 | return 0; | |
532 | ||
533 | if (waiting < 0) { | |
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); | |
542 | /* | |
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. | |
546 | */ | |
547 | code += 128; | |
548 | } else if (WIFEXITED(status)) { | |
549 | code = WEXITSTATUS(status); | |
550 | } else { | |
551 | error("waitpid is confused (%s)", argv0); | |
552 | } | |
553 | ||
554 | clear_child_for_cleanup(pid); | |
555 | ||
556 | errno = failed_errno; | |
557 | return code; | |
558 | } | |
559 | ||
560 | static void trace_add_env(struct strbuf *dst, const char *const *deltaenv) | |
561 | { | |
562 | struct string_list envs = STRING_LIST_INIT_DUP; | |
563 | const char *const *e; | |
564 | int i; | |
565 | int printed_unset = 0; | |
566 | ||
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, '='); | |
571 | ||
572 | if (equals) { | |
573 | strbuf_add(&key, *e, equals - *e); | |
574 | string_list_insert(&envs, key.buf)->util = equals + 1; | |
575 | } else { | |
576 | string_list_insert(&envs, *e)->util = NULL; | |
577 | } | |
578 | strbuf_release(&key); | |
579 | } | |
580 | ||
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; | |
585 | ||
586 | if (val || !getenv(var)) | |
587 | continue; | |
588 | ||
589 | if (!printed_unset) { | |
590 | strbuf_addstr(dst, " unset"); | |
591 | printed_unset = 1; | |
592 | } | |
593 | strbuf_addf(dst, " %s", var); | |
594 | } | |
595 | if (printed_unset) | |
596 | strbuf_addch(dst, ';'); | |
597 | ||
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; | |
602 | const char *oldval; | |
603 | ||
604 | if (!val) | |
605 | continue; | |
606 | ||
607 | oldval = getenv(var); | |
608 | if (oldval && !strcmp(val, oldval)) | |
609 | continue; | |
610 | ||
611 | strbuf_addf(dst, " %s=", var); | |
612 | sq_quote_buf_pretty(dst, val); | |
613 | } | |
614 | string_list_clear(&envs, 0); | |
615 | } | |
616 | ||
617 | static void trace_run_command(const struct child_process *cp) | |
618 | { | |
619 | struct strbuf buf = STRBUF_INIT; | |
620 | ||
621 | if (!trace_want(&trace_default_key)) | |
622 | return; | |
623 | ||
624 | strbuf_addf(&buf, "trace: run_command:"); | |
625 | /* | |
626 | * The caller is responsible for initializing cp->env from | |
627 | * cp->env_array if needed. We only check one place. | |
628 | */ | |
629 | if (cp->env) | |
630 | trace_add_env(&buf, cp->env); | |
631 | if (cp->git_cmd) | |
632 | strbuf_addstr(&buf, " git"); | |
633 | sq_quote_argv_pretty(&buf, cp->argv); | |
634 | ||
635 | trace_printf("%s", buf.buf); | |
636 | strbuf_release(&buf); | |
637 | } | |
638 | ||
639 | int start_command(struct child_process *cmd) | |
640 | { | |
641 | int need_in, need_out, need_err; | |
642 | int fdin[2], fdout[2], fderr[2]; | |
643 | int failed_errno; | |
644 | char *str; | |
645 | ||
646 | if (!cmd->argv) | |
647 | cmd->argv = cmd->args.argv; | |
648 | if (!cmd->env) | |
649 | cmd->env = cmd->env_array.argv; | |
650 | ||
651 | /* | |
652 | * In case of errors we must keep the promise to close FDs | |
653 | * that have been passed in via ->in and ->out. | |
654 | */ | |
655 | ||
656 | need_in = !cmd->no_stdin && cmd->in < 0; | |
657 | if (need_in) { | |
658 | if (pipe(fdin) < 0) { | |
659 | failed_errno = errno; | |
660 | if (cmd->out > 0) | |
661 | close(cmd->out); | |
662 | str = "standard input"; | |
663 | goto fail_pipe; | |
664 | } | |
665 | cmd->in = fdin[1]; | |
666 | } | |
667 | ||
668 | need_out = !cmd->no_stdout | |
669 | && !cmd->stdout_to_stderr | |
670 | && cmd->out < 0; | |
671 | if (need_out) { | |
672 | if (pipe(fdout) < 0) { | |
673 | failed_errno = errno; | |
674 | if (need_in) | |
675 | close_pair(fdin); | |
676 | else if (cmd->in) | |
677 | close(cmd->in); | |
678 | str = "standard output"; | |
679 | goto fail_pipe; | |
680 | } | |
681 | cmd->out = fdout[0]; | |
682 | } | |
683 | ||
684 | need_err = !cmd->no_stderr && cmd->err < 0; | |
685 | if (need_err) { | |
686 | if (pipe(fderr) < 0) { | |
687 | failed_errno = errno; | |
688 | if (need_in) | |
689 | close_pair(fdin); | |
690 | else if (cmd->in) | |
691 | close(cmd->in); | |
692 | if (need_out) | |
693 | close_pair(fdout); | |
694 | else if (cmd->out) | |
695 | close(cmd->out); | |
696 | str = "standard error"; | |
697 | fail_pipe: | |
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; | |
702 | return -1; | |
703 | } | |
704 | cmd->err = fderr[0]; | |
705 | } | |
706 | ||
707 | trace_run_command(cmd); | |
708 | ||
709 | fflush(NULL); | |
710 | ||
711 | #ifndef GIT_WINDOWS_NATIVE | |
712 | { | |
713 | int notify_pipe[2]; | |
714 | int null_fd = -1; | |
715 | char **childenv; | |
716 | struct argv_array argv = ARGV_ARRAY_INIT; | |
717 | struct child_err cerr; | |
718 | struct atfork_state as; | |
719 | ||
720 | if (pipe(notify_pipe)) | |
721 | notify_pipe[0] = notify_pipe[1] = -1; | |
722 | ||
723 | if (cmd->no_stdin || cmd->no_stdout || cmd->no_stderr) { | |
724 | null_fd = open("/dev/null", O_RDWR | O_CLOEXEC); | |
725 | if (null_fd < 0) | |
726 | die_errno(_("open /dev/null failed")); | |
727 | set_cloexec(null_fd); | |
728 | } | |
729 | ||
730 | prepare_cmd(&argv, cmd); | |
731 | childenv = prep_childenv(cmd->env); | |
732 | atfork_prepare(&as); | |
733 | ||
734 | /* | |
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. | |
742 | */ | |
743 | cmd->pid = fork(); | |
744 | failed_errno = errno; | |
745 | if (!cmd->pid) { | |
746 | int sig; | |
747 | /* | |
748 | * Ensure the default die/error/warn routines do not get | |
749 | * called, they can take stdio locks and malloc. | |
750 | */ | |
751 | set_die_routine(child_die_fn); | |
752 | set_error_routine(child_error_fn); | |
753 | set_warn_routine(child_warn_fn); | |
754 | ||
755 | close(notify_pipe[0]); | |
756 | set_cloexec(notify_pipe[1]); | |
757 | child_notifier = notify_pipe[1]; | |
758 | ||
759 | if (cmd->no_stdin) | |
760 | child_dup2(null_fd, 0); | |
761 | else if (need_in) { | |
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); | |
767 | } | |
768 | ||
769 | if (cmd->no_stderr) | |
770 | child_dup2(null_fd, 2); | |
771 | else if (need_err) { | |
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); | |
777 | } | |
778 | ||
779 | if (cmd->no_stdout) | |
780 | child_dup2(null_fd, 1); | |
781 | else if (cmd->stdout_to_stderr) | |
782 | child_dup2(2, 1); | |
783 | else if (need_out) { | |
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); | |
789 | } | |
790 | ||
791 | if (cmd->dir && chdir(cmd->dir)) | |
792 | child_die(CHILD_ERR_CHDIR); | |
793 | ||
794 | /* | |
795 | * restore default signal handlers here, in case | |
796 | * we catch a signal right before execve below | |
797 | */ | |
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); | |
802 | } | |
803 | ||
804 | if (sigprocmask(SIG_SETMASK, &as.old, NULL) != 0) | |
805 | child_die(CHILD_ERR_SIGPROCMASK); | |
806 | ||
807 | /* | |
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'. | |
812 | */ | |
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); | |
818 | ||
819 | if (errno == ENOENT) { | |
820 | if (cmd->silent_exec_failure) | |
821 | child_die(CHILD_ERR_SILENT); | |
822 | child_die(CHILD_ERR_ENOENT); | |
823 | } else { | |
824 | child_die(CHILD_ERR_ERRNO); | |
825 | } | |
826 | } | |
827 | atfork_parent(&as); | |
828 | if (cmd->pid < 0) | |
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); | |
832 | ||
833 | /* | |
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. | |
839 | */ | |
840 | close(notify_pipe[1]); | |
841 | if (xread(notify_pipe[0], &cerr, sizeof(cerr)) == sizeof(cerr)) { | |
842 | /* | |
843 | * At this point we know that fork() succeeded, but exec() | |
844 | * failed. Errors have been reported to our stderr. | |
845 | */ | |
846 | wait_or_whine(cmd->pid, cmd->argv[0], 0); | |
847 | child_err_spew(cmd, &cerr); | |
848 | failed_errno = errno; | |
849 | cmd->pid = -1; | |
850 | } | |
851 | close(notify_pipe[0]); | |
852 | ||
853 | if (null_fd >= 0) | |
854 | close(null_fd); | |
855 | argv_array_clear(&argv); | |
856 | free(childenv); | |
857 | } | |
858 | #else | |
859 | { | |
860 | int fhin = 0, fhout = 1, fherr = 2; | |
861 | const char **sargv = cmd->argv; | |
862 | struct argv_array nargv = ARGV_ARRAY_INIT; | |
863 | ||
864 | if (cmd->no_stdin) | |
865 | fhin = open("/dev/null", O_RDWR); | |
866 | else if (need_in) | |
867 | fhin = dup(fdin[0]); | |
868 | else if (cmd->in) | |
869 | fhin = dup(cmd->in); | |
870 | ||
871 | if (cmd->no_stderr) | |
872 | fherr = open("/dev/null", O_RDWR); | |
873 | else if (need_err) | |
874 | fherr = dup(fderr[1]); | |
875 | else if (cmd->err > 2) | |
876 | fherr = dup(cmd->err); | |
877 | ||
878 | if (cmd->no_stdout) | |
879 | fhout = open("/dev/null", O_RDWR); | |
880 | else if (cmd->stdout_to_stderr) | |
881 | fhout = dup(fherr); | |
882 | else if (need_out) | |
883 | fhout = dup(fdout[1]); | |
884 | else if (cmd->out > 1) | |
885 | fhout = dup(cmd->out); | |
886 | ||
887 | if (cmd->git_cmd) | |
888 | cmd->argv = prepare_git_cmd(&nargv, cmd->argv); | |
889 | else if (cmd->use_shell) | |
890 | cmd->argv = prepare_shell_cmd(&nargv, cmd->argv); | |
891 | ||
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); | |
899 | ||
900 | argv_array_clear(&nargv); | |
901 | cmd->argv = sargv; | |
902 | if (fhin != 0) | |
903 | close(fhin); | |
904 | if (fhout != 1) | |
905 | close(fhout); | |
906 | if (fherr != 2) | |
907 | close(fherr); | |
908 | } | |
909 | #endif | |
910 | ||
911 | if (cmd->pid < 0) { | |
912 | if (need_in) | |
913 | close_pair(fdin); | |
914 | else if (cmd->in) | |
915 | close(cmd->in); | |
916 | if (need_out) | |
917 | close_pair(fdout); | |
918 | else if (cmd->out) | |
919 | close(cmd->out); | |
920 | if (need_err) | |
921 | close_pair(fderr); | |
922 | else if (cmd->err) | |
923 | close(cmd->err); | |
924 | child_process_clear(cmd); | |
925 | errno = failed_errno; | |
926 | return -1; | |
927 | } | |
928 | ||
929 | if (need_in) | |
930 | close(fdin[0]); | |
931 | else if (cmd->in) | |
932 | close(cmd->in); | |
933 | ||
934 | if (need_out) | |
935 | close(fdout[1]); | |
936 | else if (cmd->out) | |
937 | close(cmd->out); | |
938 | ||
939 | if (need_err) | |
940 | close(fderr[1]); | |
941 | else if (cmd->err) | |
942 | close(cmd->err); | |
943 | ||
944 | return 0; | |
945 | } | |
946 | ||
947 | int finish_command(struct child_process *cmd) | |
948 | { | |
949 | int ret = wait_or_whine(cmd->pid, cmd->argv[0], 0); | |
950 | child_process_clear(cmd); | |
951 | return ret; | |
952 | } | |
953 | ||
954 | int finish_command_in_signal(struct child_process *cmd) | |
955 | { | |
956 | return wait_or_whine(cmd->pid, cmd->argv[0], 1); | |
957 | } | |
958 | ||
959 | ||
960 | int run_command(struct child_process *cmd) | |
961 | { | |
962 | int code; | |
963 | ||
964 | if (cmd->out < 0 || cmd->err < 0) | |
965 | die("BUG: run_command with a pipe can cause deadlock"); | |
966 | ||
967 | code = start_command(cmd); | |
968 | if (code) | |
969 | return code; | |
970 | return finish_command(cmd); | |
971 | } | |
972 | ||
973 | int run_command_v_opt(const char **argv, int opt) | |
974 | { | |
975 | return run_command_v_opt_cd_env(argv, opt, NULL, NULL); | |
976 | } | |
977 | ||
978 | int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env) | |
979 | { | |
980 | struct child_process cmd = CHILD_PROCESS_INIT; | |
981 | cmd.argv = argv; | |
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; | |
988 | cmd.dir = dir; | |
989 | cmd.env = env; | |
990 | return run_command(&cmd); | |
991 | } | |
992 | ||
993 | #ifndef NO_PTHREADS | |
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; | |
998 | ||
999 | static void *run_thread(void *data) | |
1000 | { | |
1001 | struct async *async = data; | |
1002 | intptr_t ret; | |
1003 | ||
1004 | if (async->isolate_sigpipe) { | |
1005 | sigset_t mask; | |
1006 | sigemptyset(&mask); | |
1007 | sigaddset(&mask, SIGPIPE); | |
1008 | if (pthread_sigmask(SIG_BLOCK, &mask, NULL) < 0) { | |
1009 | ret = error("unable to block SIGPIPE in async thread"); | |
1010 | return (void *)ret; | |
1011 | } | |
1012 | } | |
1013 | ||
1014 | pthread_setspecific(async_key, async); | |
1015 | ret = async->proc(async->proc_in, async->proc_out, async->data); | |
1016 | return (void *)ret; | |
1017 | } | |
1018 | ||
1019 | static NORETURN void die_async(const char *err, va_list params) | |
1020 | { | |
1021 | vreportf("fatal: ", err, params); | |
1022 | ||
1023 | if (in_async()) { | |
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); | |
1030 | } | |
1031 | ||
1032 | exit(128); | |
1033 | } | |
1034 | ||
1035 | static int async_die_is_recursing(void) | |
1036 | { | |
1037 | void *ret = pthread_getspecific(async_die_counter); | |
1038 | pthread_setspecific(async_die_counter, (void *)1); | |
1039 | return ret != NULL; | |
1040 | } | |
1041 | ||
1042 | int in_async(void) | |
1043 | { | |
1044 | if (!main_thread_set) | |
1045 | return 0; /* no asyncs started yet */ | |
1046 | return !pthread_equal(main_thread, pthread_self()); | |
1047 | } | |
1048 | ||
1049 | static void NORETURN async_exit(int code) | |
1050 | { | |
1051 | pthread_exit((void *)(intptr_t)code); | |
1052 | } | |
1053 | ||
1054 | #else | |
1055 | ||
1056 | static struct { | |
1057 | void (**handlers)(void); | |
1058 | size_t nr; | |
1059 | size_t alloc; | |
1060 | } git_atexit_hdlrs; | |
1061 | ||
1062 | static int git_atexit_installed; | |
1063 | ||
1064 | static void git_atexit_dispatch(void) | |
1065 | { | |
1066 | size_t i; | |
1067 | ||
1068 | for (i=git_atexit_hdlrs.nr ; i ; i--) | |
1069 | git_atexit_hdlrs.handlers[i-1](); | |
1070 | } | |
1071 | ||
1072 | static void git_atexit_clear(void) | |
1073 | { | |
1074 | free(git_atexit_hdlrs.handlers); | |
1075 | memset(&git_atexit_hdlrs, 0, sizeof(git_atexit_hdlrs)); | |
1076 | git_atexit_installed = 0; | |
1077 | } | |
1078 | ||
1079 | #undef atexit | |
1080 | int git_atexit(void (*handler)(void)) | |
1081 | { | |
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)) | |
1086 | return -1; | |
1087 | git_atexit_installed = 1; | |
1088 | } | |
1089 | return 0; | |
1090 | } | |
1091 | #define atexit git_atexit | |
1092 | ||
1093 | static int process_is_async; | |
1094 | int in_async(void) | |
1095 | { | |
1096 | return process_is_async; | |
1097 | } | |
1098 | ||
1099 | static void NORETURN async_exit(int code) | |
1100 | { | |
1101 | exit(code); | |
1102 | } | |
1103 | ||
1104 | #endif | |
1105 | ||
1106 | void check_pipe(int err) | |
1107 | { | |
1108 | if (err == EPIPE) { | |
1109 | if (in_async()) | |
1110 | async_exit(141); | |
1111 | ||
1112 | signal(SIGPIPE, SIG_DFL); | |
1113 | raise(SIGPIPE); | |
1114 | /* Should never happen, but just in case... */ | |
1115 | exit(141); | |
1116 | } | |
1117 | } | |
1118 | ||
1119 | int start_async(struct async *async) | |
1120 | { | |
1121 | int need_in, need_out; | |
1122 | int fdin[2], fdout[2]; | |
1123 | int proc_in, proc_out; | |
1124 | ||
1125 | need_in = async->in < 0; | |
1126 | if (need_in) { | |
1127 | if (pipe(fdin) < 0) { | |
1128 | if (async->out > 0) | |
1129 | close(async->out); | |
1130 | return error_errno("cannot create pipe"); | |
1131 | } | |
1132 | async->in = fdin[1]; | |
1133 | } | |
1134 | ||
1135 | need_out = async->out < 0; | |
1136 | if (need_out) { | |
1137 | if (pipe(fdout) < 0) { | |
1138 | if (need_in) | |
1139 | close_pair(fdin); | |
1140 | else if (async->in) | |
1141 | close(async->in); | |
1142 | return error_errno("cannot create pipe"); | |
1143 | } | |
1144 | async->out = fdout[0]; | |
1145 | } | |
1146 | ||
1147 | if (need_in) | |
1148 | proc_in = fdin[0]; | |
1149 | else if (async->in) | |
1150 | proc_in = async->in; | |
1151 | else | |
1152 | proc_in = -1; | |
1153 | ||
1154 | if (need_out) | |
1155 | proc_out = fdout[1]; | |
1156 | else if (async->out) | |
1157 | proc_out = async->out; | |
1158 | else | |
1159 | proc_out = -1; | |
1160 | ||
1161 | #ifdef NO_PTHREADS | |
1162 | /* Flush stdio before fork() to avoid cloning buffers */ | |
1163 | fflush(NULL); | |
1164 | ||
1165 | async->pid = fork(); | |
1166 | if (async->pid < 0) { | |
1167 | error_errno("fork (async) failed"); | |
1168 | goto error; | |
1169 | } | |
1170 | if (!async->pid) { | |
1171 | if (need_in) | |
1172 | close(fdin[1]); | |
1173 | if (need_out) | |
1174 | close(fdout[0]); | |
1175 | git_atexit_clear(); | |
1176 | process_is_async = 1; | |
1177 | exit(!!async->proc(proc_in, proc_out, async->data)); | |
1178 | } | |
1179 | ||
1180 | mark_child_for_cleanup(async->pid, NULL); | |
1181 | ||
1182 | if (need_in) | |
1183 | close(fdin[0]); | |
1184 | else if (async->in) | |
1185 | close(async->in); | |
1186 | ||
1187 | if (need_out) | |
1188 | close(fdout[1]); | |
1189 | else if (async->out) | |
1190 | close(async->out); | |
1191 | #else | |
1192 | if (!main_thread_set) { | |
1193 | /* | |
1194 | * We assume that the first time that start_async is called | |
1195 | * it is from the main thread. | |
1196 | */ | |
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); | |
1203 | } | |
1204 | ||
1205 | if (proc_in >= 0) | |
1206 | set_cloexec(proc_in); | |
1207 | if (proc_out >= 0) | |
1208 | set_cloexec(proc_out); | |
1209 | async->proc_in = proc_in; | |
1210 | async->proc_out = proc_out; | |
1211 | { | |
1212 | int err = pthread_create(&async->tid, NULL, run_thread, async); | |
1213 | if (err) { | |
1214 | error_errno("cannot create thread"); | |
1215 | goto error; | |
1216 | } | |
1217 | } | |
1218 | #endif | |
1219 | return 0; | |
1220 | ||
1221 | error: | |
1222 | if (need_in) | |
1223 | close_pair(fdin); | |
1224 | else if (async->in) | |
1225 | close(async->in); | |
1226 | ||
1227 | if (need_out) | |
1228 | close_pair(fdout); | |
1229 | else if (async->out) | |
1230 | close(async->out); | |
1231 | return -1; | |
1232 | } | |
1233 | ||
1234 | int finish_async(struct async *async) | |
1235 | { | |
1236 | #ifdef NO_PTHREADS | |
1237 | return wait_or_whine(async->pid, "child process", 0); | |
1238 | #else | |
1239 | void *ret = (void *)(intptr_t)(-1); | |
1240 | ||
1241 | if (pthread_join(async->tid, &ret)) | |
1242 | error("pthread_join failed"); | |
1243 | return (int)(intptr_t)ret; | |
1244 | #endif | |
1245 | } | |
1246 | ||
1247 | const char *find_hook(const char *name) | |
1248 | { | |
1249 | static struct strbuf path = STRBUF_INIT; | |
1250 | ||
1251 | strbuf_reset(&path); | |
1252 | strbuf_git_path(&path, "hooks/%s", name); | |
1253 | if (access(path.buf, X_OK) < 0) { | |
1254 | int err = errno; | |
1255 | ||
1256 | #ifdef STRIP_EXTENSION | |
1257 | strbuf_addstr(&path, STRIP_EXTENSION); | |
1258 | if (access(path.buf, X_OK) >= 0) | |
1259 | return path.buf; | |
1260 | if (errno == EACCES) | |
1261 | err = errno; | |
1262 | #endif | |
1263 | ||
1264 | if (err == EACCES && advice_ignored_hook) { | |
1265 | static struct string_list advise_given = STRING_LIST_INIT_DUP; | |
1266 | ||
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`."), | |
1273 | path.buf); | |
1274 | } | |
1275 | } | |
1276 | return NULL; | |
1277 | } | |
1278 | return path.buf; | |
1279 | } | |
1280 | ||
1281 | int run_hook_ve(const char *const *env, const char *name, va_list args) | |
1282 | { | |
1283 | struct child_process hook = CHILD_PROCESS_INIT; | |
1284 | const char *p; | |
1285 | ||
1286 | p = find_hook(name); | |
1287 | if (!p) | |
1288 | return 0; | |
1289 | ||
1290 | argv_array_push(&hook.args, p); | |
1291 | while ((p = va_arg(args, const char *))) | |
1292 | argv_array_push(&hook.args, p); | |
1293 | hook.env = env; | |
1294 | hook.no_stdin = 1; | |
1295 | hook.stdout_to_stderr = 1; | |
1296 | ||
1297 | return run_command(&hook); | |
1298 | } | |
1299 | ||
1300 | int run_hook_le(const char *const *env, const char *name, ...) | |
1301 | { | |
1302 | va_list args; | |
1303 | int ret; | |
1304 | ||
1305 | va_start(args, name); | |
1306 | ret = run_hook_ve(env, name, args); | |
1307 | va_end(args); | |
1308 | ||
1309 | return ret; | |
1310 | } | |
1311 | ||
1312 | struct io_pump { | |
1313 | /* initialized by caller */ | |
1314 | int fd; | |
1315 | int type; /* POLLOUT or POLLIN */ | |
1316 | union { | |
1317 | struct { | |
1318 | const char *buf; | |
1319 | size_t len; | |
1320 | } out; | |
1321 | struct { | |
1322 | struct strbuf *buf; | |
1323 | size_t hint; | |
1324 | } in; | |
1325 | } u; | |
1326 | ||
1327 | /* returned by pump_io */ | |
1328 | int error; /* 0 for success, otherwise errno */ | |
1329 | ||
1330 | /* internal use */ | |
1331 | struct pollfd *pfd; | |
1332 | }; | |
1333 | ||
1334 | static int pump_io_round(struct io_pump *slots, int nr, struct pollfd *pfd) | |
1335 | { | |
1336 | int pollsize = 0; | |
1337 | int i; | |
1338 | ||
1339 | for (i = 0; i < nr; i++) { | |
1340 | struct io_pump *io = &slots[i]; | |
1341 | if (io->fd < 0) | |
1342 | continue; | |
1343 | pfd[pollsize].fd = io->fd; | |
1344 | pfd[pollsize].events = io->type; | |
1345 | io->pfd = &pfd[pollsize++]; | |
1346 | } | |
1347 | ||
1348 | if (!pollsize) | |
1349 | return 0; | |
1350 | ||
1351 | if (poll(pfd, pollsize, -1) < 0) { | |
1352 | if (errno == EINTR) | |
1353 | return 1; | |
1354 | die_errno("poll failed"); | |
1355 | } | |
1356 | ||
1357 | for (i = 0; i < nr; i++) { | |
1358 | struct io_pump *io = &slots[i]; | |
1359 | ||
1360 | if (io->fd < 0) | |
1361 | continue; | |
1362 | ||
1363 | if (!(io->pfd->revents & (POLLOUT|POLLIN|POLLHUP|POLLERR|POLLNVAL))) | |
1364 | continue; | |
1365 | ||
1366 | if (io->type == POLLOUT) { | |
1367 | ssize_t len = xwrite(io->fd, | |
1368 | io->u.out.buf, io->u.out.len); | |
1369 | if (len < 0) { | |
1370 | io->error = errno; | |
1371 | close(io->fd); | |
1372 | io->fd = -1; | |
1373 | } else { | |
1374 | io->u.out.buf += len; | |
1375 | io->u.out.len -= len; | |
1376 | if (!io->u.out.len) { | |
1377 | close(io->fd); | |
1378 | io->fd = -1; | |
1379 | } | |
1380 | } | |
1381 | } | |
1382 | ||
1383 | if (io->type == POLLIN) { | |
1384 | ssize_t len = strbuf_read_once(io->u.in.buf, | |
1385 | io->fd, io->u.in.hint); | |
1386 | if (len < 0) | |
1387 | io->error = errno; | |
1388 | if (len <= 0) { | |
1389 | close(io->fd); | |
1390 | io->fd = -1; | |
1391 | } | |
1392 | } | |
1393 | } | |
1394 | ||
1395 | return 1; | |
1396 | } | |
1397 | ||
1398 | static int pump_io(struct io_pump *slots, int nr) | |
1399 | { | |
1400 | struct pollfd *pfd; | |
1401 | int i; | |
1402 | ||
1403 | for (i = 0; i < nr; i++) | |
1404 | slots[i].error = 0; | |
1405 | ||
1406 | ALLOC_ARRAY(pfd, nr); | |
1407 | while (pump_io_round(slots, nr, pfd)) | |
1408 | ; /* nothing */ | |
1409 | free(pfd); | |
1410 | ||
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; | |
1415 | return -1; | |
1416 | } | |
1417 | } | |
1418 | return 0; | |
1419 | } | |
1420 | ||
1421 | ||
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) | |
1426 | { | |
1427 | struct io_pump io[3]; | |
1428 | int nr = 0; | |
1429 | ||
1430 | if (in) | |
1431 | cmd->in = -1; | |
1432 | if (out) | |
1433 | cmd->out = -1; | |
1434 | if (err) | |
1435 | cmd->err = -1; | |
1436 | ||
1437 | if (start_command(cmd) < 0) | |
1438 | return -1; | |
1439 | ||
1440 | if (in) { | |
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; | |
1445 | nr++; | |
1446 | } | |
1447 | if (out) { | |
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; | |
1452 | nr++; | |
1453 | } | |
1454 | if (err) { | |
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; | |
1459 | nr++; | |
1460 | } | |
1461 | ||
1462 | if (pump_io(io, nr) < 0) { | |
1463 | finish_command(cmd); /* throw away exit code */ | |
1464 | return -1; | |
1465 | } | |
1466 | ||
1467 | return finish_command(cmd); | |
1468 | } | |
1469 | ||
1470 | enum child_state { | |
1471 | GIT_CP_FREE, | |
1472 | GIT_CP_WORKING, | |
1473 | GIT_CP_WAIT_CLEANUP, | |
1474 | }; | |
1475 | ||
1476 | struct parallel_processes { | |
1477 | void *data; | |
1478 | ||
1479 | int max_processes; | |
1480 | int nr_processes; | |
1481 | ||
1482 | get_next_task_fn get_next_task; | |
1483 | start_failure_fn start_failure; | |
1484 | task_finished_fn task_finished; | |
1485 | ||
1486 | struct { | |
1487 | enum child_state state; | |
1488 | struct child_process process; | |
1489 | struct strbuf err; | |
1490 | void *data; | |
1491 | } *children; | |
1492 | /* | |
1493 | * The struct pollfd is logically part of *children, | |
1494 | * but the system call expects it as its own array. | |
1495 | */ | |
1496 | struct pollfd *pfd; | |
1497 | ||
1498 | unsigned shutdown : 1; | |
1499 | ||
1500 | int output_owner; | |
1501 | struct strbuf buffered_output; /* of finished children */ | |
1502 | }; | |
1503 | ||
1504 | static int default_start_failure(struct strbuf *out, | |
1505 | void *pp_cb, | |
1506 | void *pp_task_cb) | |
1507 | { | |
1508 | return 0; | |
1509 | } | |
1510 | ||
1511 | static int default_task_finished(int result, | |
1512 | struct strbuf *out, | |
1513 | void *pp_cb, | |
1514 | void *pp_task_cb) | |
1515 | { | |
1516 | return 0; | |
1517 | } | |
1518 | ||
1519 | static void kill_children(struct parallel_processes *pp, int signo) | |
1520 | { | |
1521 | int i, n = pp->max_processes; | |
1522 | ||
1523 | for (i = 0; i < n; i++) | |
1524 | if (pp->children[i].state == GIT_CP_WORKING) | |
1525 | kill(pp->children[i].process.pid, signo); | |
1526 | } | |
1527 | ||
1528 | static struct parallel_processes *pp_for_signal; | |
1529 | ||
1530 | static void handle_children_on_signal(int signo) | |
1531 | { | |
1532 | kill_children(pp_for_signal, signo); | |
1533 | sigchain_pop(signo); | |
1534 | raise(signo); | |
1535 | } | |
1536 | ||
1537 | static void pp_init(struct parallel_processes *pp, | |
1538 | int n, | |
1539 | get_next_task_fn get_next_task, | |
1540 | start_failure_fn start_failure, | |
1541 | task_finished_fn task_finished, | |
1542 | void *data) | |
1543 | { | |
1544 | int i; | |
1545 | ||
1546 | if (n < 1) | |
1547 | n = online_cpus(); | |
1548 | ||
1549 | pp->max_processes = n; | |
1550 | ||
1551 | trace_printf("run_processes_parallel: preparing to run up to %d tasks", n); | |
1552 | ||
1553 | pp->data = data; | |
1554 | if (!get_next_task) | |
1555 | die("BUG: you need to specify a get_next_task function"); | |
1556 | pp->get_next_task = get_next_task; | |
1557 | ||
1558 | pp->start_failure = start_failure ? start_failure : default_start_failure; | |
1559 | pp->task_finished = task_finished ? task_finished : default_task_finished; | |
1560 | ||
1561 | pp->nr_processes = 0; | |
1562 | pp->output_owner = 0; | |
1563 | pp->shutdown = 0; | |
1564 | pp->children = xcalloc(n, sizeof(*pp->children)); | |
1565 | pp->pfd = xcalloc(n, sizeof(*pp->pfd)); | |
1566 | strbuf_init(&pp->buffered_output, 0); | |
1567 | ||
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; | |
1572 | pp->pfd[i].fd = -1; | |
1573 | } | |
1574 | ||
1575 | pp_for_signal = pp; | |
1576 | sigchain_push_common(handle_children_on_signal); | |
1577 | } | |
1578 | ||
1579 | static void pp_cleanup(struct parallel_processes *pp) | |
1580 | { | |
1581 | int i; | |
1582 | ||
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); | |
1587 | } | |
1588 | ||
1589 | free(pp->children); | |
1590 | free(pp->pfd); | |
1591 | ||
1592 | /* | |
1593 | * When get_next_task added messages to the buffer in its last | |
1594 | * iteration, the buffered output is non empty. | |
1595 | */ | |
1596 | strbuf_write(&pp->buffered_output, stderr); | |
1597 | strbuf_release(&pp->buffered_output); | |
1598 | ||
1599 | sigchain_pop_common(); | |
1600 | } | |
1601 | ||
1602 | /* returns | |
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. | |
1608 | */ | |
1609 | static int pp_start_one(struct parallel_processes *pp) | |
1610 | { | |
1611 | int i, code; | |
1612 | ||
1613 | for (i = 0; i < pp->max_processes; i++) | |
1614 | if (pp->children[i].state == GIT_CP_FREE) | |
1615 | break; | |
1616 | if (i == pp->max_processes) | |
1617 | die("BUG: bookkeeping is hard"); | |
1618 | ||
1619 | code = pp->get_next_task(&pp->children[i].process, | |
1620 | &pp->children[i].err, | |
1621 | pp->data, | |
1622 | &pp->children[i].data); | |
1623 | if (!code) { | |
1624 | strbuf_addbuf(&pp->buffered_output, &pp->children[i].err); | |
1625 | strbuf_reset(&pp->children[i].err); | |
1626 | return 1; | |
1627 | } | |
1628 | pp->children[i].process.err = -1; | |
1629 | pp->children[i].process.stdout_to_stderr = 1; | |
1630 | pp->children[i].process.no_stdin = 1; | |
1631 | ||
1632 | if (start_command(&pp->children[i].process)) { | |
1633 | code = pp->start_failure(&pp->children[i].err, | |
1634 | pp->data, | |
1635 | pp->children[i].data); | |
1636 | strbuf_addbuf(&pp->buffered_output, &pp->children[i].err); | |
1637 | strbuf_reset(&pp->children[i].err); | |
1638 | if (code) | |
1639 | pp->shutdown = 1; | |
1640 | return code; | |
1641 | } | |
1642 | ||
1643 | pp->nr_processes++; | |
1644 | pp->children[i].state = GIT_CP_WORKING; | |
1645 | pp->pfd[i].fd = pp->children[i].process.err; | |
1646 | return 0; | |
1647 | } | |
1648 | ||
1649 | static void pp_buffer_stderr(struct parallel_processes *pp, int output_timeout) | |
1650 | { | |
1651 | int i; | |
1652 | ||
1653 | while ((i = poll(pp->pfd, pp->max_processes, output_timeout)) < 0) { | |
1654 | if (errno == EINTR) | |
1655 | continue; | |
1656 | pp_cleanup(pp); | |
1657 | die_errno("poll"); | |
1658 | } | |
1659 | ||
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); | |
1666 | if (n == 0) { | |
1667 | close(pp->children[i].process.err); | |
1668 | pp->children[i].state = GIT_CP_WAIT_CLEANUP; | |
1669 | } else if (n < 0) | |
1670 | if (errno != EAGAIN) | |
1671 | die_errno("read"); | |
1672 | } | |
1673 | } | |
1674 | } | |
1675 | ||
1676 | static void pp_output(struct parallel_processes *pp) | |
1677 | { | |
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); | |
1683 | } | |
1684 | } | |
1685 | ||
1686 | static int pp_collect_finished(struct parallel_processes *pp) | |
1687 | { | |
1688 | int i, code; | |
1689 | int n = pp->max_processes; | |
1690 | int result = 0; | |
1691 | ||
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) | |
1695 | break; | |
1696 | if (i == pp->max_processes) | |
1697 | break; | |
1698 | ||
1699 | code = finish_command(&pp->children[i].process); | |
1700 | ||
1701 | code = pp->task_finished(code, | |
1702 | &pp->children[i].err, pp->data, | |
1703 | pp->children[i].data); | |
1704 | ||
1705 | if (code) | |
1706 | result = code; | |
1707 | if (code < 0) | |
1708 | break; | |
1709 | ||
1710 | pp->nr_processes--; | |
1711 | pp->children[i].state = GIT_CP_FREE; | |
1712 | pp->pfd[i].fd = -1; | |
1713 | child_process_init(&pp->children[i].process); | |
1714 | ||
1715 | if (i != pp->output_owner) { | |
1716 | strbuf_addbuf(&pp->buffered_output, &pp->children[i].err); | |
1717 | strbuf_reset(&pp->children[i].err); | |
1718 | } else { | |
1719 | strbuf_write(&pp->children[i].err, stderr); | |
1720 | strbuf_reset(&pp->children[i].err); | |
1721 | ||
1722 | /* Output all other finished child processes */ | |
1723 | strbuf_write(&pp->buffered_output, stderr); | |
1724 | strbuf_reset(&pp->buffered_output); | |
1725 | ||
1726 | /* | |
1727 | * Pick next process to output live. | |
1728 | * NEEDSWORK: | |
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. | |
1733 | */ | |
1734 | for (i = 0; i < n; i++) | |
1735 | if (pp->children[(pp->output_owner + i) % n].state == GIT_CP_WORKING) | |
1736 | break; | |
1737 | pp->output_owner = (pp->output_owner + i) % n; | |
1738 | } | |
1739 | } | |
1740 | return result; | |
1741 | } | |
1742 | ||
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, | |
1747 | void *pp_cb) | |
1748 | { | |
1749 | int i, code; | |
1750 | int output_timeout = 100; | |
1751 | int spawn_cap = 4; | |
1752 | struct parallel_processes pp; | |
1753 | ||
1754 | pp_init(&pp, n, get_next_task, start_failure, task_finished, pp_cb); | |
1755 | while (1) { | |
1756 | for (i = 0; | |
1757 | i < spawn_cap && !pp.shutdown && | |
1758 | pp.nr_processes < pp.max_processes; | |
1759 | i++) { | |
1760 | code = pp_start_one(&pp); | |
1761 | if (!code) | |
1762 | continue; | |
1763 | if (code < 0) { | |
1764 | pp.shutdown = 1; | |
1765 | kill_children(&pp, -code); | |
1766 | } | |
1767 | break; | |
1768 | } | |
1769 | if (!pp.nr_processes) | |
1770 | break; | |
1771 | pp_buffer_stderr(&pp, output_timeout); | |
1772 | pp_output(&pp); | |
1773 | code = pp_collect_finished(&pp); | |
1774 | if (code) { | |
1775 | pp.shutdown = 1; | |
1776 | if (code < 0) | |
1777 | kill_children(&pp, -code); | |
1778 | } | |
1779 | } | |
1780 | ||
1781 | pp_cleanup(&pp); | |
1782 | return 0; | |
1783 | } |