]>
Commit | Line | Data |
---|---|---|
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 | int found = r != NULL; | |
217 | free(r); | |
218 | return found; | |
219 | } | |
220 | ||
221 | int sane_execvp(const char *file, char * const argv[]) | |
222 | { | |
223 | #ifndef GIT_WINDOWS_NATIVE | |
224 | /* | |
225 | * execvp() doesn't return, so we all we can do is tell trace2 | |
226 | * what we are about to do and let it leave a hint in the log | |
227 | * (unless of course the execvp() fails). | |
228 | * | |
229 | * we skip this for Windows because the compat layer already | |
230 | * has to emulate the execvp() call anyway. | |
231 | */ | |
232 | int exec_id = trace2_exec(file, (const char **)argv); | |
233 | #endif | |
234 | ||
235 | if (!execvp(file, argv)) | |
236 | return 0; /* cannot happen ;-) */ | |
237 | ||
238 | #ifndef GIT_WINDOWS_NATIVE | |
239 | { | |
240 | int ec = errno; | |
241 | trace2_exec_result(exec_id, ec); | |
242 | errno = ec; | |
243 | } | |
244 | #endif | |
245 | ||
246 | /* | |
247 | * When a command can't be found because one of the directories | |
248 | * listed in $PATH is unsearchable, execvp reports EACCES, but | |
249 | * careful usability testing (read: analysis of occasional bug | |
250 | * reports) reveals that "No such file or directory" is more | |
251 | * intuitive. | |
252 | * | |
253 | * We avoid commands with "/", because execvp will not do $PATH | |
254 | * lookups in that case. | |
255 | * | |
256 | * The reassignment of EACCES to errno looks like a no-op below, | |
257 | * but we need to protect against exists_in_PATH overwriting errno. | |
258 | */ | |
259 | if (errno == EACCES && !strchr(file, '/')) | |
260 | errno = exists_in_PATH(file) ? EACCES : ENOENT; | |
261 | else if (errno == ENOTDIR && !strchr(file, '/')) | |
262 | errno = ENOENT; | |
263 | return -1; | |
264 | } | |
265 | ||
266 | static const char **prepare_shell_cmd(struct argv_array *out, const char **argv) | |
267 | { | |
268 | if (!argv[0]) | |
269 | BUG("shell command is empty"); | |
270 | ||
271 | if (strcspn(argv[0], "|&;<>()$`\\\"' \t\n*?[#~=%") != strlen(argv[0])) { | |
272 | #ifndef GIT_WINDOWS_NATIVE | |
273 | argv_array_push(out, SHELL_PATH); | |
274 | #else | |
275 | argv_array_push(out, "sh"); | |
276 | #endif | |
277 | argv_array_push(out, "-c"); | |
278 | ||
279 | /* | |
280 | * If we have no extra arguments, we do not even need to | |
281 | * bother with the "$@" magic. | |
282 | */ | |
283 | if (!argv[1]) | |
284 | argv_array_push(out, argv[0]); | |
285 | else | |
286 | argv_array_pushf(out, "%s \"$@\"", argv[0]); | |
287 | } | |
288 | ||
289 | argv_array_pushv(out, argv); | |
290 | return out->argv; | |
291 | } | |
292 | ||
293 | #ifndef GIT_WINDOWS_NATIVE | |
294 | static int child_notifier = -1; | |
295 | ||
296 | enum child_errcode { | |
297 | CHILD_ERR_CHDIR, | |
298 | CHILD_ERR_DUP2, | |
299 | CHILD_ERR_CLOSE, | |
300 | CHILD_ERR_SIGPROCMASK, | |
301 | CHILD_ERR_ENOENT, | |
302 | CHILD_ERR_SILENT, | |
303 | CHILD_ERR_ERRNO | |
304 | }; | |
305 | ||
306 | struct child_err { | |
307 | enum child_errcode err; | |
308 | int syserr; /* errno */ | |
309 | }; | |
310 | ||
311 | static void child_die(enum child_errcode err) | |
312 | { | |
313 | struct child_err buf; | |
314 | ||
315 | buf.err = err; | |
316 | buf.syserr = errno; | |
317 | ||
318 | /* write(2) on buf smaller than PIPE_BUF (min 512) is atomic: */ | |
319 | xwrite(child_notifier, &buf, sizeof(buf)); | |
320 | _exit(1); | |
321 | } | |
322 | ||
323 | static void child_dup2(int fd, int to) | |
324 | { | |
325 | if (dup2(fd, to) < 0) | |
326 | child_die(CHILD_ERR_DUP2); | |
327 | } | |
328 | ||
329 | static void child_close(int fd) | |
330 | { | |
331 | if (close(fd)) | |
332 | child_die(CHILD_ERR_CLOSE); | |
333 | } | |
334 | ||
335 | static void child_close_pair(int fd[2]) | |
336 | { | |
337 | child_close(fd[0]); | |
338 | child_close(fd[1]); | |
339 | } | |
340 | ||
341 | /* | |
342 | * parent will make it look like the child spewed a fatal error and died | |
343 | * this is needed to prevent changes to t0061. | |
344 | */ | |
345 | static void fake_fatal(const char *err, va_list params) | |
346 | { | |
347 | vreportf("fatal: ", err, params); | |
348 | } | |
349 | ||
350 | static void child_error_fn(const char *err, va_list params) | |
351 | { | |
352 | const char msg[] = "error() should not be called in child\n"; | |
353 | xwrite(2, msg, sizeof(msg) - 1); | |
354 | } | |
355 | ||
356 | static void child_warn_fn(const char *err, va_list params) | |
357 | { | |
358 | const char msg[] = "warn() should not be called in child\n"; | |
359 | xwrite(2, msg, sizeof(msg) - 1); | |
360 | } | |
361 | ||
362 | static void NORETURN child_die_fn(const char *err, va_list params) | |
363 | { | |
364 | const char msg[] = "die() should not be called in child\n"; | |
365 | xwrite(2, msg, sizeof(msg) - 1); | |
366 | _exit(2); | |
367 | } | |
368 | ||
369 | /* this runs in the parent process */ | |
370 | static void child_err_spew(struct child_process *cmd, struct child_err *cerr) | |
371 | { | |
372 | static void (*old_errfn)(const char *err, va_list params); | |
373 | ||
374 | old_errfn = get_error_routine(); | |
375 | set_error_routine(fake_fatal); | |
376 | errno = cerr->syserr; | |
377 | ||
378 | switch (cerr->err) { | |
379 | case CHILD_ERR_CHDIR: | |
380 | error_errno("exec '%s': cd to '%s' failed", | |
381 | cmd->argv[0], cmd->dir); | |
382 | break; | |
383 | case CHILD_ERR_DUP2: | |
384 | error_errno("dup2() in child failed"); | |
385 | break; | |
386 | case CHILD_ERR_CLOSE: | |
387 | error_errno("close() in child failed"); | |
388 | break; | |
389 | case CHILD_ERR_SIGPROCMASK: | |
390 | error_errno("sigprocmask failed restoring signals"); | |
391 | break; | |
392 | case CHILD_ERR_ENOENT: | |
393 | error_errno("cannot run %s", cmd->argv[0]); | |
394 | break; | |
395 | case CHILD_ERR_SILENT: | |
396 | break; | |
397 | case CHILD_ERR_ERRNO: | |
398 | error_errno("cannot exec '%s'", cmd->argv[0]); | |
399 | break; | |
400 | } | |
401 | set_error_routine(old_errfn); | |
402 | } | |
403 | ||
404 | static int prepare_cmd(struct argv_array *out, const struct child_process *cmd) | |
405 | { | |
406 | if (!cmd->argv[0]) | |
407 | BUG("command is empty"); | |
408 | ||
409 | /* | |
410 | * Add SHELL_PATH so in the event exec fails with ENOEXEC we can | |
411 | * attempt to interpret the command with 'sh'. | |
412 | */ | |
413 | argv_array_push(out, SHELL_PATH); | |
414 | ||
415 | if (cmd->git_cmd) { | |
416 | prepare_git_cmd(out, cmd->argv); | |
417 | } else if (cmd->use_shell) { | |
418 | prepare_shell_cmd(out, cmd->argv); | |
419 | } else { | |
420 | argv_array_pushv(out, cmd->argv); | |
421 | } | |
422 | ||
423 | /* | |
424 | * If there are no '/' characters in the command then perform a path | |
425 | * lookup and use the resolved path as the command to exec. If there | |
426 | * are '/' characters, we have exec attempt to invoke the command | |
427 | * directly. | |
428 | */ | |
429 | if (!strchr(out->argv[1], '/')) { | |
430 | char *program = locate_in_PATH(out->argv[1]); | |
431 | if (program) { | |
432 | free((char *)out->argv[1]); | |
433 | out->argv[1] = program; | |
434 | } else { | |
435 | argv_array_clear(out); | |
436 | errno = ENOENT; | |
437 | return -1; | |
438 | } | |
439 | } | |
440 | ||
441 | return 0; | |
442 | } | |
443 | ||
444 | static char **prep_childenv(const char *const *deltaenv) | |
445 | { | |
446 | extern char **environ; | |
447 | char **childenv; | |
448 | struct string_list env = STRING_LIST_INIT_DUP; | |
449 | struct strbuf key = STRBUF_INIT; | |
450 | const char *const *p; | |
451 | int i; | |
452 | ||
453 | /* Construct a sorted string list consisting of the current environ */ | |
454 | for (p = (const char *const *) environ; p && *p; p++) { | |
455 | const char *equals = strchr(*p, '='); | |
456 | ||
457 | if (equals) { | |
458 | strbuf_reset(&key); | |
459 | strbuf_add(&key, *p, equals - *p); | |
460 | string_list_append(&env, key.buf)->util = (void *) *p; | |
461 | } else { | |
462 | string_list_append(&env, *p)->util = (void *) *p; | |
463 | } | |
464 | } | |
465 | string_list_sort(&env); | |
466 | ||
467 | /* Merge in 'deltaenv' with the current environ */ | |
468 | for (p = deltaenv; p && *p; p++) { | |
469 | const char *equals = strchr(*p, '='); | |
470 | ||
471 | if (equals) { | |
472 | /* ('key=value'), insert or replace entry */ | |
473 | strbuf_reset(&key); | |
474 | strbuf_add(&key, *p, equals - *p); | |
475 | string_list_insert(&env, key.buf)->util = (void *) *p; | |
476 | } else { | |
477 | /* otherwise ('key') remove existing entry */ | |
478 | string_list_remove(&env, *p, 0); | |
479 | } | |
480 | } | |
481 | ||
482 | /* Create an array of 'char *' to be used as the childenv */ | |
483 | ALLOC_ARRAY(childenv, env.nr + 1); | |
484 | for (i = 0; i < env.nr; i++) | |
485 | childenv[i] = env.items[i].util; | |
486 | childenv[env.nr] = NULL; | |
487 | ||
488 | string_list_clear(&env, 0); | |
489 | strbuf_release(&key); | |
490 | return childenv; | |
491 | } | |
492 | ||
493 | struct atfork_state { | |
494 | #ifndef NO_PTHREADS | |
495 | int cs; | |
496 | #endif | |
497 | sigset_t old; | |
498 | }; | |
499 | ||
500 | #define CHECK_BUG(err, msg) \ | |
501 | do { \ | |
502 | int e = (err); \ | |
503 | if (e) \ | |
504 | BUG("%s: %s", msg, strerror(e)); \ | |
505 | } while(0) | |
506 | ||
507 | static void atfork_prepare(struct atfork_state *as) | |
508 | { | |
509 | sigset_t all; | |
510 | ||
511 | if (sigfillset(&all)) | |
512 | die_errno("sigfillset"); | |
513 | #ifdef NO_PTHREADS | |
514 | if (sigprocmask(SIG_SETMASK, &all, &as->old)) | |
515 | die_errno("sigprocmask"); | |
516 | #else | |
517 | CHECK_BUG(pthread_sigmask(SIG_SETMASK, &all, &as->old), | |
518 | "blocking all signals"); | |
519 | CHECK_BUG(pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &as->cs), | |
520 | "disabling cancellation"); | |
521 | #endif | |
522 | } | |
523 | ||
524 | static void atfork_parent(struct atfork_state *as) | |
525 | { | |
526 | #ifdef NO_PTHREADS | |
527 | if (sigprocmask(SIG_SETMASK, &as->old, NULL)) | |
528 | die_errno("sigprocmask"); | |
529 | #else | |
530 | CHECK_BUG(pthread_setcancelstate(as->cs, NULL), | |
531 | "re-enabling cancellation"); | |
532 | CHECK_BUG(pthread_sigmask(SIG_SETMASK, &as->old, NULL), | |
533 | "restoring signal mask"); | |
534 | #endif | |
535 | } | |
536 | #endif /* GIT_WINDOWS_NATIVE */ | |
537 | ||
538 | static inline void set_cloexec(int fd) | |
539 | { | |
540 | int flags = fcntl(fd, F_GETFD); | |
541 | if (flags >= 0) | |
542 | fcntl(fd, F_SETFD, flags | FD_CLOEXEC); | |
543 | } | |
544 | ||
545 | static int wait_or_whine(pid_t pid, const char *argv0, int in_signal) | |
546 | { | |
547 | int status, code = -1; | |
548 | pid_t waiting; | |
549 | int failed_errno = 0; | |
550 | ||
551 | while ((waiting = waitpid(pid, &status, 0)) < 0 && errno == EINTR) | |
552 | ; /* nothing */ | |
553 | if (in_signal) | |
554 | return 0; | |
555 | ||
556 | if (waiting < 0) { | |
557 | failed_errno = errno; | |
558 | error_errno("waitpid for %s failed", argv0); | |
559 | } else if (waiting != pid) { | |
560 | error("waitpid is confused (%s)", argv0); | |
561 | } else if (WIFSIGNALED(status)) { | |
562 | code = WTERMSIG(status); | |
563 | if (code != SIGINT && code != SIGQUIT && code != SIGPIPE) | |
564 | error("%s died of signal %d", argv0, code); | |
565 | /* | |
566 | * This return value is chosen so that code & 0xff | |
567 | * mimics the exit code that a POSIX shell would report for | |
568 | * a program that died from this signal. | |
569 | */ | |
570 | code += 128; | |
571 | } else if (WIFEXITED(status)) { | |
572 | code = WEXITSTATUS(status); | |
573 | } else { | |
574 | error("waitpid is confused (%s)", argv0); | |
575 | } | |
576 | ||
577 | clear_child_for_cleanup(pid); | |
578 | ||
579 | errno = failed_errno; | |
580 | return code; | |
581 | } | |
582 | ||
583 | static void trace_add_env(struct strbuf *dst, const char *const *deltaenv) | |
584 | { | |
585 | struct string_list envs = STRING_LIST_INIT_DUP; | |
586 | const char *const *e; | |
587 | int i; | |
588 | int printed_unset = 0; | |
589 | ||
590 | /* Last one wins, see run-command.c:prep_childenv() for context */ | |
591 | for (e = deltaenv; e && *e; e++) { | |
592 | struct strbuf key = STRBUF_INIT; | |
593 | char *equals = strchr(*e, '='); | |
594 | ||
595 | if (equals) { | |
596 | strbuf_add(&key, *e, equals - *e); | |
597 | string_list_insert(&envs, key.buf)->util = equals + 1; | |
598 | } else { | |
599 | string_list_insert(&envs, *e)->util = NULL; | |
600 | } | |
601 | strbuf_release(&key); | |
602 | } | |
603 | ||
604 | /* "unset X Y...;" */ | |
605 | for (i = 0; i < envs.nr; i++) { | |
606 | const char *var = envs.items[i].string; | |
607 | const char *val = envs.items[i].util; | |
608 | ||
609 | if (val || !getenv(var)) | |
610 | continue; | |
611 | ||
612 | if (!printed_unset) { | |
613 | strbuf_addstr(dst, " unset"); | |
614 | printed_unset = 1; | |
615 | } | |
616 | strbuf_addf(dst, " %s", var); | |
617 | } | |
618 | if (printed_unset) | |
619 | strbuf_addch(dst, ';'); | |
620 | ||
621 | /* ... followed by "A=B C=D ..." */ | |
622 | for (i = 0; i < envs.nr; i++) { | |
623 | const char *var = envs.items[i].string; | |
624 | const char *val = envs.items[i].util; | |
625 | const char *oldval; | |
626 | ||
627 | if (!val) | |
628 | continue; | |
629 | ||
630 | oldval = getenv(var); | |
631 | if (oldval && !strcmp(val, oldval)) | |
632 | continue; | |
633 | ||
634 | strbuf_addf(dst, " %s=", var); | |
635 | sq_quote_buf_pretty(dst, val); | |
636 | } | |
637 | string_list_clear(&envs, 0); | |
638 | } | |
639 | ||
640 | static void trace_run_command(const struct child_process *cp) | |
641 | { | |
642 | struct strbuf buf = STRBUF_INIT; | |
643 | ||
644 | if (!trace_want(&trace_default_key)) | |
645 | return; | |
646 | ||
647 | strbuf_addstr(&buf, "trace: run_command:"); | |
648 | if (cp->dir) { | |
649 | strbuf_addstr(&buf, " cd "); | |
650 | sq_quote_buf_pretty(&buf, cp->dir); | |
651 | strbuf_addch(&buf, ';'); | |
652 | } | |
653 | /* | |
654 | * The caller is responsible for initializing cp->env from | |
655 | * cp->env_array if needed. We only check one place. | |
656 | */ | |
657 | if (cp->env) | |
658 | trace_add_env(&buf, cp->env); | |
659 | if (cp->git_cmd) | |
660 | strbuf_addstr(&buf, " git"); | |
661 | sq_quote_argv_pretty(&buf, cp->argv); | |
662 | ||
663 | trace_printf("%s", buf.buf); | |
664 | strbuf_release(&buf); | |
665 | } | |
666 | ||
667 | int start_command(struct child_process *cmd) | |
668 | { | |
669 | int need_in, need_out, need_err; | |
670 | int fdin[2], fdout[2], fderr[2]; | |
671 | int failed_errno; | |
672 | char *str; | |
673 | ||
674 | if (!cmd->argv) | |
675 | cmd->argv = cmd->args.argv; | |
676 | if (!cmd->env) | |
677 | cmd->env = cmd->env_array.argv; | |
678 | ||
679 | /* | |
680 | * In case of errors we must keep the promise to close FDs | |
681 | * that have been passed in via ->in and ->out. | |
682 | */ | |
683 | ||
684 | need_in = !cmd->no_stdin && cmd->in < 0; | |
685 | if (need_in) { | |
686 | if (pipe(fdin) < 0) { | |
687 | failed_errno = errno; | |
688 | if (cmd->out > 0) | |
689 | close(cmd->out); | |
690 | str = "standard input"; | |
691 | goto fail_pipe; | |
692 | } | |
693 | cmd->in = fdin[1]; | |
694 | } | |
695 | ||
696 | need_out = !cmd->no_stdout | |
697 | && !cmd->stdout_to_stderr | |
698 | && cmd->out < 0; | |
699 | if (need_out) { | |
700 | if (pipe(fdout) < 0) { | |
701 | failed_errno = errno; | |
702 | if (need_in) | |
703 | close_pair(fdin); | |
704 | else if (cmd->in) | |
705 | close(cmd->in); | |
706 | str = "standard output"; | |
707 | goto fail_pipe; | |
708 | } | |
709 | cmd->out = fdout[0]; | |
710 | } | |
711 | ||
712 | need_err = !cmd->no_stderr && cmd->err < 0; | |
713 | if (need_err) { | |
714 | if (pipe(fderr) < 0) { | |
715 | failed_errno = errno; | |
716 | if (need_in) | |
717 | close_pair(fdin); | |
718 | else if (cmd->in) | |
719 | close(cmd->in); | |
720 | if (need_out) | |
721 | close_pair(fdout); | |
722 | else if (cmd->out) | |
723 | close(cmd->out); | |
724 | str = "standard error"; | |
725 | fail_pipe: | |
726 | error("cannot create %s pipe for %s: %s", | |
727 | str, cmd->argv[0], strerror(failed_errno)); | |
728 | child_process_clear(cmd); | |
729 | errno = failed_errno; | |
730 | return -1; | |
731 | } | |
732 | cmd->err = fderr[0]; | |
733 | } | |
734 | ||
735 | trace2_child_start(cmd); | |
736 | trace_run_command(cmd); | |
737 | ||
738 | fflush(NULL); | |
739 | ||
740 | #ifndef GIT_WINDOWS_NATIVE | |
741 | { | |
742 | int notify_pipe[2]; | |
743 | int null_fd = -1; | |
744 | char **childenv; | |
745 | struct argv_array argv = ARGV_ARRAY_INIT; | |
746 | struct child_err cerr; | |
747 | struct atfork_state as; | |
748 | ||
749 | if (prepare_cmd(&argv, cmd) < 0) { | |
750 | failed_errno = errno; | |
751 | cmd->pid = -1; | |
752 | if (!cmd->silent_exec_failure) | |
753 | error_errno("cannot run %s", cmd->argv[0]); | |
754 | goto end_of_spawn; | |
755 | } | |
756 | ||
757 | if (pipe(notify_pipe)) | |
758 | notify_pipe[0] = notify_pipe[1] = -1; | |
759 | ||
760 | if (cmd->no_stdin || cmd->no_stdout || cmd->no_stderr) { | |
761 | null_fd = open("/dev/null", O_RDWR | O_CLOEXEC); | |
762 | if (null_fd < 0) | |
763 | die_errno(_("open /dev/null failed")); | |
764 | set_cloexec(null_fd); | |
765 | } | |
766 | ||
767 | childenv = prep_childenv(cmd->env); | |
768 | atfork_prepare(&as); | |
769 | ||
770 | /* | |
771 | * NOTE: In order to prevent deadlocking when using threads special | |
772 | * care should be taken with the function calls made in between the | |
773 | * fork() and exec() calls. No calls should be made to functions which | |
774 | * require acquiring a lock (e.g. malloc) as the lock could have been | |
775 | * held by another thread at the time of forking, causing the lock to | |
776 | * never be released in the child process. This means only | |
777 | * Async-Signal-Safe functions are permitted in the child. | |
778 | */ | |
779 | cmd->pid = fork(); | |
780 | failed_errno = errno; | |
781 | if (!cmd->pid) { | |
782 | int sig; | |
783 | /* | |
784 | * Ensure the default die/error/warn routines do not get | |
785 | * called, they can take stdio locks and malloc. | |
786 | */ | |
787 | set_die_routine(child_die_fn); | |
788 | set_error_routine(child_error_fn); | |
789 | set_warn_routine(child_warn_fn); | |
790 | ||
791 | close(notify_pipe[0]); | |
792 | set_cloexec(notify_pipe[1]); | |
793 | child_notifier = notify_pipe[1]; | |
794 | ||
795 | if (cmd->no_stdin) | |
796 | child_dup2(null_fd, 0); | |
797 | else if (need_in) { | |
798 | child_dup2(fdin[0], 0); | |
799 | child_close_pair(fdin); | |
800 | } else if (cmd->in) { | |
801 | child_dup2(cmd->in, 0); | |
802 | child_close(cmd->in); | |
803 | } | |
804 | ||
805 | if (cmd->no_stderr) | |
806 | child_dup2(null_fd, 2); | |
807 | else if (need_err) { | |
808 | child_dup2(fderr[1], 2); | |
809 | child_close_pair(fderr); | |
810 | } else if (cmd->err > 1) { | |
811 | child_dup2(cmd->err, 2); | |
812 | child_close(cmd->err); | |
813 | } | |
814 | ||
815 | if (cmd->no_stdout) | |
816 | child_dup2(null_fd, 1); | |
817 | else if (cmd->stdout_to_stderr) | |
818 | child_dup2(2, 1); | |
819 | else if (need_out) { | |
820 | child_dup2(fdout[1], 1); | |
821 | child_close_pair(fdout); | |
822 | } else if (cmd->out > 1) { | |
823 | child_dup2(cmd->out, 1); | |
824 | child_close(cmd->out); | |
825 | } | |
826 | ||
827 | if (cmd->dir && chdir(cmd->dir)) | |
828 | child_die(CHILD_ERR_CHDIR); | |
829 | ||
830 | /* | |
831 | * restore default signal handlers here, in case | |
832 | * we catch a signal right before execve below | |
833 | */ | |
834 | for (sig = 1; sig < NSIG; sig++) { | |
835 | /* ignored signals get reset to SIG_DFL on execve */ | |
836 | if (signal(sig, SIG_DFL) == SIG_IGN) | |
837 | signal(sig, SIG_IGN); | |
838 | } | |
839 | ||
840 | if (sigprocmask(SIG_SETMASK, &as.old, NULL) != 0) | |
841 | child_die(CHILD_ERR_SIGPROCMASK); | |
842 | ||
843 | /* | |
844 | * Attempt to exec using the command and arguments starting at | |
845 | * argv.argv[1]. argv.argv[0] contains SHELL_PATH which will | |
846 | * be used in the event exec failed with ENOEXEC at which point | |
847 | * we will try to interpret the command using 'sh'. | |
848 | */ | |
849 | execve(argv.argv[1], (char *const *) argv.argv + 1, | |
850 | (char *const *) childenv); | |
851 | if (errno == ENOEXEC) | |
852 | execve(argv.argv[0], (char *const *) argv.argv, | |
853 | (char *const *) childenv); | |
854 | ||
855 | if (errno == ENOENT) { | |
856 | if (cmd->silent_exec_failure) | |
857 | child_die(CHILD_ERR_SILENT); | |
858 | child_die(CHILD_ERR_ENOENT); | |
859 | } else { | |
860 | child_die(CHILD_ERR_ERRNO); | |
861 | } | |
862 | } | |
863 | atfork_parent(&as); | |
864 | if (cmd->pid < 0) | |
865 | error_errno("cannot fork() for %s", cmd->argv[0]); | |
866 | else if (cmd->clean_on_exit) | |
867 | mark_child_for_cleanup(cmd->pid, cmd); | |
868 | ||
869 | /* | |
870 | * Wait for child's exec. If the exec succeeds (or if fork() | |
871 | * failed), EOF is seen immediately by the parent. Otherwise, the | |
872 | * child process sends a child_err struct. | |
873 | * Note that use of this infrastructure is completely advisory, | |
874 | * therefore, we keep error checks minimal. | |
875 | */ | |
876 | close(notify_pipe[1]); | |
877 | if (xread(notify_pipe[0], &cerr, sizeof(cerr)) == sizeof(cerr)) { | |
878 | /* | |
879 | * At this point we know that fork() succeeded, but exec() | |
880 | * failed. Errors have been reported to our stderr. | |
881 | */ | |
882 | wait_or_whine(cmd->pid, cmd->argv[0], 0); | |
883 | child_err_spew(cmd, &cerr); | |
884 | failed_errno = errno; | |
885 | cmd->pid = -1; | |
886 | } | |
887 | close(notify_pipe[0]); | |
888 | ||
889 | if (null_fd >= 0) | |
890 | close(null_fd); | |
891 | argv_array_clear(&argv); | |
892 | free(childenv); | |
893 | } | |
894 | end_of_spawn: | |
895 | ||
896 | #else | |
897 | { | |
898 | int fhin = 0, fhout = 1, fherr = 2; | |
899 | const char **sargv = cmd->argv; | |
900 | struct argv_array nargv = ARGV_ARRAY_INIT; | |
901 | ||
902 | if (cmd->no_stdin) | |
903 | fhin = open("/dev/null", O_RDWR); | |
904 | else if (need_in) | |
905 | fhin = dup(fdin[0]); | |
906 | else if (cmd->in) | |
907 | fhin = dup(cmd->in); | |
908 | ||
909 | if (cmd->no_stderr) | |
910 | fherr = open("/dev/null", O_RDWR); | |
911 | else if (need_err) | |
912 | fherr = dup(fderr[1]); | |
913 | else if (cmd->err > 2) | |
914 | fherr = dup(cmd->err); | |
915 | ||
916 | if (cmd->no_stdout) | |
917 | fhout = open("/dev/null", O_RDWR); | |
918 | else if (cmd->stdout_to_stderr) | |
919 | fhout = dup(fherr); | |
920 | else if (need_out) | |
921 | fhout = dup(fdout[1]); | |
922 | else if (cmd->out > 1) | |
923 | fhout = dup(cmd->out); | |
924 | ||
925 | if (cmd->git_cmd) | |
926 | cmd->argv = prepare_git_cmd(&nargv, cmd->argv); | |
927 | else if (cmd->use_shell) | |
928 | cmd->argv = prepare_shell_cmd(&nargv, cmd->argv); | |
929 | ||
930 | cmd->pid = mingw_spawnvpe(cmd->argv[0], cmd->argv, (char**) cmd->env, | |
931 | cmd->dir, fhin, fhout, fherr); | |
932 | failed_errno = errno; | |
933 | if (cmd->pid < 0 && (!cmd->silent_exec_failure || errno != ENOENT)) | |
934 | error_errno("cannot spawn %s", cmd->argv[0]); | |
935 | if (cmd->clean_on_exit && cmd->pid >= 0) | |
936 | mark_child_for_cleanup(cmd->pid, cmd); | |
937 | ||
938 | argv_array_clear(&nargv); | |
939 | cmd->argv = sargv; | |
940 | if (fhin != 0) | |
941 | close(fhin); | |
942 | if (fhout != 1) | |
943 | close(fhout); | |
944 | if (fherr != 2) | |
945 | close(fherr); | |
946 | } | |
947 | #endif | |
948 | ||
949 | if (cmd->pid < 0) { | |
950 | trace2_child_exit(cmd, -1); | |
951 | ||
952 | if (need_in) | |
953 | close_pair(fdin); | |
954 | else if (cmd->in) | |
955 | close(cmd->in); | |
956 | if (need_out) | |
957 | close_pair(fdout); | |
958 | else if (cmd->out) | |
959 | close(cmd->out); | |
960 | if (need_err) | |
961 | close_pair(fderr); | |
962 | else if (cmd->err) | |
963 | close(cmd->err); | |
964 | child_process_clear(cmd); | |
965 | errno = failed_errno; | |
966 | return -1; | |
967 | } | |
968 | ||
969 | if (need_in) | |
970 | close(fdin[0]); | |
971 | else if (cmd->in) | |
972 | close(cmd->in); | |
973 | ||
974 | if (need_out) | |
975 | close(fdout[1]); | |
976 | else if (cmd->out) | |
977 | close(cmd->out); | |
978 | ||
979 | if (need_err) | |
980 | close(fderr[1]); | |
981 | else if (cmd->err) | |
982 | close(cmd->err); | |
983 | ||
984 | return 0; | |
985 | } | |
986 | ||
987 | int finish_command(struct child_process *cmd) | |
988 | { | |
989 | int ret = wait_or_whine(cmd->pid, cmd->argv[0], 0); | |
990 | trace2_child_exit(cmd, ret); | |
991 | child_process_clear(cmd); | |
992 | return ret; | |
993 | } | |
994 | ||
995 | int finish_command_in_signal(struct child_process *cmd) | |
996 | { | |
997 | int ret = wait_or_whine(cmd->pid, cmd->argv[0], 1); | |
998 | trace2_child_exit(cmd, ret); | |
999 | return ret; | |
1000 | } | |
1001 | ||
1002 | ||
1003 | int run_command(struct child_process *cmd) | |
1004 | { | |
1005 | int code; | |
1006 | ||
1007 | if (cmd->out < 0 || cmd->err < 0) | |
1008 | BUG("run_command with a pipe can cause deadlock"); | |
1009 | ||
1010 | code = start_command(cmd); | |
1011 | if (code) | |
1012 | return code; | |
1013 | return finish_command(cmd); | |
1014 | } | |
1015 | ||
1016 | int run_command_v_opt(const char **argv, int opt) | |
1017 | { | |
1018 | return run_command_v_opt_cd_env(argv, opt, NULL, NULL); | |
1019 | } | |
1020 | ||
1021 | int run_command_v_opt_tr2(const char **argv, int opt, const char *tr2_class) | |
1022 | { | |
1023 | return run_command_v_opt_cd_env_tr2(argv, opt, NULL, NULL, tr2_class); | |
1024 | } | |
1025 | ||
1026 | int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env) | |
1027 | { | |
1028 | return run_command_v_opt_cd_env_tr2(argv, opt, dir, env, NULL); | |
1029 | } | |
1030 | ||
1031 | int run_command_v_opt_cd_env_tr2(const char **argv, int opt, const char *dir, | |
1032 | const char *const *env, const char *tr2_class) | |
1033 | { | |
1034 | struct child_process cmd = CHILD_PROCESS_INIT; | |
1035 | cmd.argv = argv; | |
1036 | cmd.no_stdin = opt & RUN_COMMAND_NO_STDIN ? 1 : 0; | |
1037 | cmd.git_cmd = opt & RUN_GIT_CMD ? 1 : 0; | |
1038 | cmd.stdout_to_stderr = opt & RUN_COMMAND_STDOUT_TO_STDERR ? 1 : 0; | |
1039 | cmd.silent_exec_failure = opt & RUN_SILENT_EXEC_FAILURE ? 1 : 0; | |
1040 | cmd.use_shell = opt & RUN_USING_SHELL ? 1 : 0; | |
1041 | cmd.clean_on_exit = opt & RUN_CLEAN_ON_EXIT ? 1 : 0; | |
1042 | cmd.dir = dir; | |
1043 | cmd.env = env; | |
1044 | cmd.trace2_child_class = tr2_class; | |
1045 | return run_command(&cmd); | |
1046 | } | |
1047 | ||
1048 | #ifndef NO_PTHREADS | |
1049 | static pthread_t main_thread; | |
1050 | static int main_thread_set; | |
1051 | static pthread_key_t async_key; | |
1052 | static pthread_key_t async_die_counter; | |
1053 | ||
1054 | static void *run_thread(void *data) | |
1055 | { | |
1056 | struct async *async = data; | |
1057 | intptr_t ret; | |
1058 | ||
1059 | if (async->isolate_sigpipe) { | |
1060 | sigset_t mask; | |
1061 | sigemptyset(&mask); | |
1062 | sigaddset(&mask, SIGPIPE); | |
1063 | if (pthread_sigmask(SIG_BLOCK, &mask, NULL) < 0) { | |
1064 | ret = error("unable to block SIGPIPE in async thread"); | |
1065 | return (void *)ret; | |
1066 | } | |
1067 | } | |
1068 | ||
1069 | pthread_setspecific(async_key, async); | |
1070 | ret = async->proc(async->proc_in, async->proc_out, async->data); | |
1071 | return (void *)ret; | |
1072 | } | |
1073 | ||
1074 | static NORETURN void die_async(const char *err, va_list params) | |
1075 | { | |
1076 | vreportf("fatal: ", err, params); | |
1077 | ||
1078 | if (in_async()) { | |
1079 | struct async *async = pthread_getspecific(async_key); | |
1080 | if (async->proc_in >= 0) | |
1081 | close(async->proc_in); | |
1082 | if (async->proc_out >= 0) | |
1083 | close(async->proc_out); | |
1084 | pthread_exit((void *)128); | |
1085 | } | |
1086 | ||
1087 | exit(128); | |
1088 | } | |
1089 | ||
1090 | static int async_die_is_recursing(void) | |
1091 | { | |
1092 | void *ret = pthread_getspecific(async_die_counter); | |
1093 | pthread_setspecific(async_die_counter, (void *)1); | |
1094 | return ret != NULL; | |
1095 | } | |
1096 | ||
1097 | int in_async(void) | |
1098 | { | |
1099 | if (!main_thread_set) | |
1100 | return 0; /* no asyncs started yet */ | |
1101 | return !pthread_equal(main_thread, pthread_self()); | |
1102 | } | |
1103 | ||
1104 | static void NORETURN async_exit(int code) | |
1105 | { | |
1106 | pthread_exit((void *)(intptr_t)code); | |
1107 | } | |
1108 | ||
1109 | #else | |
1110 | ||
1111 | static struct { | |
1112 | void (**handlers)(void); | |
1113 | size_t nr; | |
1114 | size_t alloc; | |
1115 | } git_atexit_hdlrs; | |
1116 | ||
1117 | static int git_atexit_installed; | |
1118 | ||
1119 | static void git_atexit_dispatch(void) | |
1120 | { | |
1121 | size_t i; | |
1122 | ||
1123 | for (i=git_atexit_hdlrs.nr ; i ; i--) | |
1124 | git_atexit_hdlrs.handlers[i-1](); | |
1125 | } | |
1126 | ||
1127 | static void git_atexit_clear(void) | |
1128 | { | |
1129 | free(git_atexit_hdlrs.handlers); | |
1130 | memset(&git_atexit_hdlrs, 0, sizeof(git_atexit_hdlrs)); | |
1131 | git_atexit_installed = 0; | |
1132 | } | |
1133 | ||
1134 | #undef atexit | |
1135 | int git_atexit(void (*handler)(void)) | |
1136 | { | |
1137 | ALLOC_GROW(git_atexit_hdlrs.handlers, git_atexit_hdlrs.nr + 1, git_atexit_hdlrs.alloc); | |
1138 | git_atexit_hdlrs.handlers[git_atexit_hdlrs.nr++] = handler; | |
1139 | if (!git_atexit_installed) { | |
1140 | if (atexit(&git_atexit_dispatch)) | |
1141 | return -1; | |
1142 | git_atexit_installed = 1; | |
1143 | } | |
1144 | return 0; | |
1145 | } | |
1146 | #define atexit git_atexit | |
1147 | ||
1148 | static int process_is_async; | |
1149 | int in_async(void) | |
1150 | { | |
1151 | return process_is_async; | |
1152 | } | |
1153 | ||
1154 | static void NORETURN async_exit(int code) | |
1155 | { | |
1156 | exit(code); | |
1157 | } | |
1158 | ||
1159 | #endif | |
1160 | ||
1161 | void check_pipe(int err) | |
1162 | { | |
1163 | if (err == EPIPE) { | |
1164 | if (in_async()) | |
1165 | async_exit(141); | |
1166 | ||
1167 | signal(SIGPIPE, SIG_DFL); | |
1168 | raise(SIGPIPE); | |
1169 | /* Should never happen, but just in case... */ | |
1170 | exit(141); | |
1171 | } | |
1172 | } | |
1173 | ||
1174 | int start_async(struct async *async) | |
1175 | { | |
1176 | int need_in, need_out; | |
1177 | int fdin[2], fdout[2]; | |
1178 | int proc_in, proc_out; | |
1179 | ||
1180 | need_in = async->in < 0; | |
1181 | if (need_in) { | |
1182 | if (pipe(fdin) < 0) { | |
1183 | if (async->out > 0) | |
1184 | close(async->out); | |
1185 | return error_errno("cannot create pipe"); | |
1186 | } | |
1187 | async->in = fdin[1]; | |
1188 | } | |
1189 | ||
1190 | need_out = async->out < 0; | |
1191 | if (need_out) { | |
1192 | if (pipe(fdout) < 0) { | |
1193 | if (need_in) | |
1194 | close_pair(fdin); | |
1195 | else if (async->in) | |
1196 | close(async->in); | |
1197 | return error_errno("cannot create pipe"); | |
1198 | } | |
1199 | async->out = fdout[0]; | |
1200 | } | |
1201 | ||
1202 | if (need_in) | |
1203 | proc_in = fdin[0]; | |
1204 | else if (async->in) | |
1205 | proc_in = async->in; | |
1206 | else | |
1207 | proc_in = -1; | |
1208 | ||
1209 | if (need_out) | |
1210 | proc_out = fdout[1]; | |
1211 | else if (async->out) | |
1212 | proc_out = async->out; | |
1213 | else | |
1214 | proc_out = -1; | |
1215 | ||
1216 | #ifdef NO_PTHREADS | |
1217 | /* Flush stdio before fork() to avoid cloning buffers */ | |
1218 | fflush(NULL); | |
1219 | ||
1220 | async->pid = fork(); | |
1221 | if (async->pid < 0) { | |
1222 | error_errno("fork (async) failed"); | |
1223 | goto error; | |
1224 | } | |
1225 | if (!async->pid) { | |
1226 | if (need_in) | |
1227 | close(fdin[1]); | |
1228 | if (need_out) | |
1229 | close(fdout[0]); | |
1230 | git_atexit_clear(); | |
1231 | process_is_async = 1; | |
1232 | exit(!!async->proc(proc_in, proc_out, async->data)); | |
1233 | } | |
1234 | ||
1235 | mark_child_for_cleanup(async->pid, NULL); | |
1236 | ||
1237 | if (need_in) | |
1238 | close(fdin[0]); | |
1239 | else if (async->in) | |
1240 | close(async->in); | |
1241 | ||
1242 | if (need_out) | |
1243 | close(fdout[1]); | |
1244 | else if (async->out) | |
1245 | close(async->out); | |
1246 | #else | |
1247 | if (!main_thread_set) { | |
1248 | /* | |
1249 | * We assume that the first time that start_async is called | |
1250 | * it is from the main thread. | |
1251 | */ | |
1252 | main_thread_set = 1; | |
1253 | main_thread = pthread_self(); | |
1254 | pthread_key_create(&async_key, NULL); | |
1255 | pthread_key_create(&async_die_counter, NULL); | |
1256 | set_die_routine(die_async); | |
1257 | set_die_is_recursing_routine(async_die_is_recursing); | |
1258 | } | |
1259 | ||
1260 | if (proc_in >= 0) | |
1261 | set_cloexec(proc_in); | |
1262 | if (proc_out >= 0) | |
1263 | set_cloexec(proc_out); | |
1264 | async->proc_in = proc_in; | |
1265 | async->proc_out = proc_out; | |
1266 | { | |
1267 | int err = pthread_create(&async->tid, NULL, run_thread, async); | |
1268 | if (err) { | |
1269 | error(_("cannot create async thread: %s"), strerror(err)); | |
1270 | goto error; | |
1271 | } | |
1272 | } | |
1273 | #endif | |
1274 | return 0; | |
1275 | ||
1276 | error: | |
1277 | if (need_in) | |
1278 | close_pair(fdin); | |
1279 | else if (async->in) | |
1280 | close(async->in); | |
1281 | ||
1282 | if (need_out) | |
1283 | close_pair(fdout); | |
1284 | else if (async->out) | |
1285 | close(async->out); | |
1286 | return -1; | |
1287 | } | |
1288 | ||
1289 | int finish_async(struct async *async) | |
1290 | { | |
1291 | #ifdef NO_PTHREADS | |
1292 | return wait_or_whine(async->pid, "child process", 0); | |
1293 | #else | |
1294 | void *ret = (void *)(intptr_t)(-1); | |
1295 | ||
1296 | if (pthread_join(async->tid, &ret)) | |
1297 | error("pthread_join failed"); | |
1298 | return (int)(intptr_t)ret; | |
1299 | #endif | |
1300 | } | |
1301 | ||
1302 | int async_with_fork(void) | |
1303 | { | |
1304 | #ifdef NO_PTHREADS | |
1305 | return 1; | |
1306 | #else | |
1307 | return 0; | |
1308 | #endif | |
1309 | } | |
1310 | ||
1311 | const char *find_hook(const char *name) | |
1312 | { | |
1313 | static struct strbuf path = STRBUF_INIT; | |
1314 | ||
1315 | strbuf_reset(&path); | |
1316 | strbuf_git_path(&path, "hooks/%s", name); | |
1317 | if (access(path.buf, X_OK) < 0) { | |
1318 | int err = errno; | |
1319 | ||
1320 | #ifdef STRIP_EXTENSION | |
1321 | strbuf_addstr(&path, STRIP_EXTENSION); | |
1322 | if (access(path.buf, X_OK) >= 0) | |
1323 | return path.buf; | |
1324 | if (errno == EACCES) | |
1325 | err = errno; | |
1326 | #endif | |
1327 | ||
1328 | if (err == EACCES && advice_ignored_hook) { | |
1329 | static struct string_list advise_given = STRING_LIST_INIT_DUP; | |
1330 | ||
1331 | if (!string_list_lookup(&advise_given, name)) { | |
1332 | string_list_insert(&advise_given, name); | |
1333 | advise(_("The '%s' hook was ignored because " | |
1334 | "it's not set as executable.\n" | |
1335 | "You can disable this warning with " | |
1336 | "`git config advice.ignoredHook false`."), | |
1337 | path.buf); | |
1338 | } | |
1339 | } | |
1340 | return NULL; | |
1341 | } | |
1342 | return path.buf; | |
1343 | } | |
1344 | ||
1345 | int run_hook_ve(const char *const *env, const char *name, va_list args) | |
1346 | { | |
1347 | struct child_process hook = CHILD_PROCESS_INIT; | |
1348 | const char *p; | |
1349 | ||
1350 | p = find_hook(name); | |
1351 | if (!p) | |
1352 | return 0; | |
1353 | ||
1354 | argv_array_push(&hook.args, p); | |
1355 | while ((p = va_arg(args, const char *))) | |
1356 | argv_array_push(&hook.args, p); | |
1357 | hook.env = env; | |
1358 | hook.no_stdin = 1; | |
1359 | hook.stdout_to_stderr = 1; | |
1360 | hook.trace2_hook_name = name; | |
1361 | ||
1362 | return run_command(&hook); | |
1363 | } | |
1364 | ||
1365 | int run_hook_le(const char *const *env, const char *name, ...) | |
1366 | { | |
1367 | va_list args; | |
1368 | int ret; | |
1369 | ||
1370 | va_start(args, name); | |
1371 | ret = run_hook_ve(env, name, args); | |
1372 | va_end(args); | |
1373 | ||
1374 | return ret; | |
1375 | } | |
1376 | ||
1377 | struct io_pump { | |
1378 | /* initialized by caller */ | |
1379 | int fd; | |
1380 | int type; /* POLLOUT or POLLIN */ | |
1381 | union { | |
1382 | struct { | |
1383 | const char *buf; | |
1384 | size_t len; | |
1385 | } out; | |
1386 | struct { | |
1387 | struct strbuf *buf; | |
1388 | size_t hint; | |
1389 | } in; | |
1390 | } u; | |
1391 | ||
1392 | /* returned by pump_io */ | |
1393 | int error; /* 0 for success, otherwise errno */ | |
1394 | ||
1395 | /* internal use */ | |
1396 | struct pollfd *pfd; | |
1397 | }; | |
1398 | ||
1399 | static int pump_io_round(struct io_pump *slots, int nr, struct pollfd *pfd) | |
1400 | { | |
1401 | int pollsize = 0; | |
1402 | int i; | |
1403 | ||
1404 | for (i = 0; i < nr; i++) { | |
1405 | struct io_pump *io = &slots[i]; | |
1406 | if (io->fd < 0) | |
1407 | continue; | |
1408 | pfd[pollsize].fd = io->fd; | |
1409 | pfd[pollsize].events = io->type; | |
1410 | io->pfd = &pfd[pollsize++]; | |
1411 | } | |
1412 | ||
1413 | if (!pollsize) | |
1414 | return 0; | |
1415 | ||
1416 | if (poll(pfd, pollsize, -1) < 0) { | |
1417 | if (errno == EINTR) | |
1418 | return 1; | |
1419 | die_errno("poll failed"); | |
1420 | } | |
1421 | ||
1422 | for (i = 0; i < nr; i++) { | |
1423 | struct io_pump *io = &slots[i]; | |
1424 | ||
1425 | if (io->fd < 0) | |
1426 | continue; | |
1427 | ||
1428 | if (!(io->pfd->revents & (POLLOUT|POLLIN|POLLHUP|POLLERR|POLLNVAL))) | |
1429 | continue; | |
1430 | ||
1431 | if (io->type == POLLOUT) { | |
1432 | ssize_t len = xwrite(io->fd, | |
1433 | io->u.out.buf, io->u.out.len); | |
1434 | if (len < 0) { | |
1435 | io->error = errno; | |
1436 | close(io->fd); | |
1437 | io->fd = -1; | |
1438 | } else { | |
1439 | io->u.out.buf += len; | |
1440 | io->u.out.len -= len; | |
1441 | if (!io->u.out.len) { | |
1442 | close(io->fd); | |
1443 | io->fd = -1; | |
1444 | } | |
1445 | } | |
1446 | } | |
1447 | ||
1448 | if (io->type == POLLIN) { | |
1449 | ssize_t len = strbuf_read_once(io->u.in.buf, | |
1450 | io->fd, io->u.in.hint); | |
1451 | if (len < 0) | |
1452 | io->error = errno; | |
1453 | if (len <= 0) { | |
1454 | close(io->fd); | |
1455 | io->fd = -1; | |
1456 | } | |
1457 | } | |
1458 | } | |
1459 | ||
1460 | return 1; | |
1461 | } | |
1462 | ||
1463 | static int pump_io(struct io_pump *slots, int nr) | |
1464 | { | |
1465 | struct pollfd *pfd; | |
1466 | int i; | |
1467 | ||
1468 | for (i = 0; i < nr; i++) | |
1469 | slots[i].error = 0; | |
1470 | ||
1471 | ALLOC_ARRAY(pfd, nr); | |
1472 | while (pump_io_round(slots, nr, pfd)) | |
1473 | ; /* nothing */ | |
1474 | free(pfd); | |
1475 | ||
1476 | /* There may be multiple errno values, so just pick the first. */ | |
1477 | for (i = 0; i < nr; i++) { | |
1478 | if (slots[i].error) { | |
1479 | errno = slots[i].error; | |
1480 | return -1; | |
1481 | } | |
1482 | } | |
1483 | return 0; | |
1484 | } | |
1485 | ||
1486 | ||
1487 | int pipe_command(struct child_process *cmd, | |
1488 | const char *in, size_t in_len, | |
1489 | struct strbuf *out, size_t out_hint, | |
1490 | struct strbuf *err, size_t err_hint) | |
1491 | { | |
1492 | struct io_pump io[3]; | |
1493 | int nr = 0; | |
1494 | ||
1495 | if (in) | |
1496 | cmd->in = -1; | |
1497 | if (out) | |
1498 | cmd->out = -1; | |
1499 | if (err) | |
1500 | cmd->err = -1; | |
1501 | ||
1502 | if (start_command(cmd) < 0) | |
1503 | return -1; | |
1504 | ||
1505 | if (in) { | |
1506 | io[nr].fd = cmd->in; | |
1507 | io[nr].type = POLLOUT; | |
1508 | io[nr].u.out.buf = in; | |
1509 | io[nr].u.out.len = in_len; | |
1510 | nr++; | |
1511 | } | |
1512 | if (out) { | |
1513 | io[nr].fd = cmd->out; | |
1514 | io[nr].type = POLLIN; | |
1515 | io[nr].u.in.buf = out; | |
1516 | io[nr].u.in.hint = out_hint; | |
1517 | nr++; | |
1518 | } | |
1519 | if (err) { | |
1520 | io[nr].fd = cmd->err; | |
1521 | io[nr].type = POLLIN; | |
1522 | io[nr].u.in.buf = err; | |
1523 | io[nr].u.in.hint = err_hint; | |
1524 | nr++; | |
1525 | } | |
1526 | ||
1527 | if (pump_io(io, nr) < 0) { | |
1528 | finish_command(cmd); /* throw away exit code */ | |
1529 | return -1; | |
1530 | } | |
1531 | ||
1532 | return finish_command(cmd); | |
1533 | } | |
1534 | ||
1535 | enum child_state { | |
1536 | GIT_CP_FREE, | |
1537 | GIT_CP_WORKING, | |
1538 | GIT_CP_WAIT_CLEANUP, | |
1539 | }; | |
1540 | ||
1541 | struct parallel_processes { | |
1542 | void *data; | |
1543 | ||
1544 | int max_processes; | |
1545 | int nr_processes; | |
1546 | ||
1547 | get_next_task_fn get_next_task; | |
1548 | start_failure_fn start_failure; | |
1549 | task_finished_fn task_finished; | |
1550 | ||
1551 | struct { | |
1552 | enum child_state state; | |
1553 | struct child_process process; | |
1554 | struct strbuf err; | |
1555 | void *data; | |
1556 | } *children; | |
1557 | /* | |
1558 | * The struct pollfd is logically part of *children, | |
1559 | * but the system call expects it as its own array. | |
1560 | */ | |
1561 | struct pollfd *pfd; | |
1562 | ||
1563 | unsigned shutdown : 1; | |
1564 | ||
1565 | int output_owner; | |
1566 | struct strbuf buffered_output; /* of finished children */ | |
1567 | }; | |
1568 | ||
1569 | static int default_start_failure(struct strbuf *out, | |
1570 | void *pp_cb, | |
1571 | void *pp_task_cb) | |
1572 | { | |
1573 | return 0; | |
1574 | } | |
1575 | ||
1576 | static int default_task_finished(int result, | |
1577 | struct strbuf *out, | |
1578 | void *pp_cb, | |
1579 | void *pp_task_cb) | |
1580 | { | |
1581 | return 0; | |
1582 | } | |
1583 | ||
1584 | static void kill_children(struct parallel_processes *pp, int signo) | |
1585 | { | |
1586 | int i, n = pp->max_processes; | |
1587 | ||
1588 | for (i = 0; i < n; i++) | |
1589 | if (pp->children[i].state == GIT_CP_WORKING) | |
1590 | kill(pp->children[i].process.pid, signo); | |
1591 | } | |
1592 | ||
1593 | static struct parallel_processes *pp_for_signal; | |
1594 | ||
1595 | static void handle_children_on_signal(int signo) | |
1596 | { | |
1597 | kill_children(pp_for_signal, signo); | |
1598 | sigchain_pop(signo); | |
1599 | raise(signo); | |
1600 | } | |
1601 | ||
1602 | static void pp_init(struct parallel_processes *pp, | |
1603 | int n, | |
1604 | get_next_task_fn get_next_task, | |
1605 | start_failure_fn start_failure, | |
1606 | task_finished_fn task_finished, | |
1607 | void *data) | |
1608 | { | |
1609 | int i; | |
1610 | ||
1611 | if (n < 1) | |
1612 | n = online_cpus(); | |
1613 | ||
1614 | pp->max_processes = n; | |
1615 | ||
1616 | trace_printf("run_processes_parallel: preparing to run up to %d tasks", n); | |
1617 | ||
1618 | pp->data = data; | |
1619 | if (!get_next_task) | |
1620 | BUG("you need to specify a get_next_task function"); | |
1621 | pp->get_next_task = get_next_task; | |
1622 | ||
1623 | pp->start_failure = start_failure ? start_failure : default_start_failure; | |
1624 | pp->task_finished = task_finished ? task_finished : default_task_finished; | |
1625 | ||
1626 | pp->nr_processes = 0; | |
1627 | pp->output_owner = 0; | |
1628 | pp->shutdown = 0; | |
1629 | pp->children = xcalloc(n, sizeof(*pp->children)); | |
1630 | pp->pfd = xcalloc(n, sizeof(*pp->pfd)); | |
1631 | strbuf_init(&pp->buffered_output, 0); | |
1632 | ||
1633 | for (i = 0; i < n; i++) { | |
1634 | strbuf_init(&pp->children[i].err, 0); | |
1635 | child_process_init(&pp->children[i].process); | |
1636 | pp->pfd[i].events = POLLIN | POLLHUP; | |
1637 | pp->pfd[i].fd = -1; | |
1638 | } | |
1639 | ||
1640 | pp_for_signal = pp; | |
1641 | sigchain_push_common(handle_children_on_signal); | |
1642 | } | |
1643 | ||
1644 | static void pp_cleanup(struct parallel_processes *pp) | |
1645 | { | |
1646 | int i; | |
1647 | ||
1648 | trace_printf("run_processes_parallel: done"); | |
1649 | for (i = 0; i < pp->max_processes; i++) { | |
1650 | strbuf_release(&pp->children[i].err); | |
1651 | child_process_clear(&pp->children[i].process); | |
1652 | } | |
1653 | ||
1654 | free(pp->children); | |
1655 | free(pp->pfd); | |
1656 | ||
1657 | /* | |
1658 | * When get_next_task added messages to the buffer in its last | |
1659 | * iteration, the buffered output is non empty. | |
1660 | */ | |
1661 | strbuf_write(&pp->buffered_output, stderr); | |
1662 | strbuf_release(&pp->buffered_output); | |
1663 | ||
1664 | sigchain_pop_common(); | |
1665 | } | |
1666 | ||
1667 | /* returns | |
1668 | * 0 if a new task was started. | |
1669 | * 1 if no new jobs was started (get_next_task ran out of work, non critical | |
1670 | * problem with starting a new command) | |
1671 | * <0 no new job was started, user wishes to shutdown early. Use negative code | |
1672 | * to signal the children. | |
1673 | */ | |
1674 | static int pp_start_one(struct parallel_processes *pp) | |
1675 | { | |
1676 | int i, code; | |
1677 | ||
1678 | for (i = 0; i < pp->max_processes; i++) | |
1679 | if (pp->children[i].state == GIT_CP_FREE) | |
1680 | break; | |
1681 | if (i == pp->max_processes) | |
1682 | BUG("bookkeeping is hard"); | |
1683 | ||
1684 | code = pp->get_next_task(&pp->children[i].process, | |
1685 | &pp->children[i].err, | |
1686 | pp->data, | |
1687 | &pp->children[i].data); | |
1688 | if (!code) { | |
1689 | strbuf_addbuf(&pp->buffered_output, &pp->children[i].err); | |
1690 | strbuf_reset(&pp->children[i].err); | |
1691 | return 1; | |
1692 | } | |
1693 | pp->children[i].process.err = -1; | |
1694 | pp->children[i].process.stdout_to_stderr = 1; | |
1695 | pp->children[i].process.no_stdin = 1; | |
1696 | ||
1697 | if (start_command(&pp->children[i].process)) { | |
1698 | code = pp->start_failure(&pp->children[i].err, | |
1699 | pp->data, | |
1700 | pp->children[i].data); | |
1701 | strbuf_addbuf(&pp->buffered_output, &pp->children[i].err); | |
1702 | strbuf_reset(&pp->children[i].err); | |
1703 | if (code) | |
1704 | pp->shutdown = 1; | |
1705 | return code; | |
1706 | } | |
1707 | ||
1708 | pp->nr_processes++; | |
1709 | pp->children[i].state = GIT_CP_WORKING; | |
1710 | pp->pfd[i].fd = pp->children[i].process.err; | |
1711 | return 0; | |
1712 | } | |
1713 | ||
1714 | static void pp_buffer_stderr(struct parallel_processes *pp, int output_timeout) | |
1715 | { | |
1716 | int i; | |
1717 | ||
1718 | while ((i = poll(pp->pfd, pp->max_processes, output_timeout)) < 0) { | |
1719 | if (errno == EINTR) | |
1720 | continue; | |
1721 | pp_cleanup(pp); | |
1722 | die_errno("poll"); | |
1723 | } | |
1724 | ||
1725 | /* Buffer output from all pipes. */ | |
1726 | for (i = 0; i < pp->max_processes; i++) { | |
1727 | if (pp->children[i].state == GIT_CP_WORKING && | |
1728 | pp->pfd[i].revents & (POLLIN | POLLHUP)) { | |
1729 | int n = strbuf_read_once(&pp->children[i].err, | |
1730 | pp->children[i].process.err, 0); | |
1731 | if (n == 0) { | |
1732 | close(pp->children[i].process.err); | |
1733 | pp->children[i].state = GIT_CP_WAIT_CLEANUP; | |
1734 | } else if (n < 0) | |
1735 | if (errno != EAGAIN) | |
1736 | die_errno("read"); | |
1737 | } | |
1738 | } | |
1739 | } | |
1740 | ||
1741 | static void pp_output(struct parallel_processes *pp) | |
1742 | { | |
1743 | int i = pp->output_owner; | |
1744 | if (pp->children[i].state == GIT_CP_WORKING && | |
1745 | pp->children[i].err.len) { | |
1746 | strbuf_write(&pp->children[i].err, stderr); | |
1747 | strbuf_reset(&pp->children[i].err); | |
1748 | } | |
1749 | } | |
1750 | ||
1751 | static int pp_collect_finished(struct parallel_processes *pp) | |
1752 | { | |
1753 | int i, code; | |
1754 | int n = pp->max_processes; | |
1755 | int result = 0; | |
1756 | ||
1757 | while (pp->nr_processes > 0) { | |
1758 | for (i = 0; i < pp->max_processes; i++) | |
1759 | if (pp->children[i].state == GIT_CP_WAIT_CLEANUP) | |
1760 | break; | |
1761 | if (i == pp->max_processes) | |
1762 | break; | |
1763 | ||
1764 | code = finish_command(&pp->children[i].process); | |
1765 | ||
1766 | code = pp->task_finished(code, | |
1767 | &pp->children[i].err, pp->data, | |
1768 | pp->children[i].data); | |
1769 | ||
1770 | if (code) | |
1771 | result = code; | |
1772 | if (code < 0) | |
1773 | break; | |
1774 | ||
1775 | pp->nr_processes--; | |
1776 | pp->children[i].state = GIT_CP_FREE; | |
1777 | pp->pfd[i].fd = -1; | |
1778 | child_process_init(&pp->children[i].process); | |
1779 | ||
1780 | if (i != pp->output_owner) { | |
1781 | strbuf_addbuf(&pp->buffered_output, &pp->children[i].err); | |
1782 | strbuf_reset(&pp->children[i].err); | |
1783 | } else { | |
1784 | strbuf_write(&pp->children[i].err, stderr); | |
1785 | strbuf_reset(&pp->children[i].err); | |
1786 | ||
1787 | /* Output all other finished child processes */ | |
1788 | strbuf_write(&pp->buffered_output, stderr); | |
1789 | strbuf_reset(&pp->buffered_output); | |
1790 | ||
1791 | /* | |
1792 | * Pick next process to output live. | |
1793 | * NEEDSWORK: | |
1794 | * For now we pick it randomly by doing a round | |
1795 | * robin. Later we may want to pick the one with | |
1796 | * the most output or the longest or shortest | |
1797 | * running process time. | |
1798 | */ | |
1799 | for (i = 0; i < n; i++) | |
1800 | if (pp->children[(pp->output_owner + i) % n].state == GIT_CP_WORKING) | |
1801 | break; | |
1802 | pp->output_owner = (pp->output_owner + i) % n; | |
1803 | } | |
1804 | } | |
1805 | return result; | |
1806 | } | |
1807 | ||
1808 | int run_processes_parallel(int n, | |
1809 | get_next_task_fn get_next_task, | |
1810 | start_failure_fn start_failure, | |
1811 | task_finished_fn task_finished, | |
1812 | void *pp_cb) | |
1813 | { | |
1814 | int i, code; | |
1815 | int output_timeout = 100; | |
1816 | int spawn_cap = 4; | |
1817 | struct parallel_processes pp; | |
1818 | ||
1819 | pp_init(&pp, n, get_next_task, start_failure, task_finished, pp_cb); | |
1820 | while (1) { | |
1821 | for (i = 0; | |
1822 | i < spawn_cap && !pp.shutdown && | |
1823 | pp.nr_processes < pp.max_processes; | |
1824 | i++) { | |
1825 | code = pp_start_one(&pp); | |
1826 | if (!code) | |
1827 | continue; | |
1828 | if (code < 0) { | |
1829 | pp.shutdown = 1; | |
1830 | kill_children(&pp, -code); | |
1831 | } | |
1832 | break; | |
1833 | } | |
1834 | if (!pp.nr_processes) | |
1835 | break; | |
1836 | pp_buffer_stderr(&pp, output_timeout); | |
1837 | pp_output(&pp); | |
1838 | code = pp_collect_finished(&pp); | |
1839 | if (code) { | |
1840 | pp.shutdown = 1; | |
1841 | if (code < 0) | |
1842 | kill_children(&pp, -code); | |
1843 | } | |
1844 | } | |
1845 | ||
1846 | pp_cleanup(&pp); | |
1847 | return 0; | |
1848 | } | |
1849 | ||
1850 | int run_processes_parallel_tr2(int n, get_next_task_fn get_next_task, | |
1851 | start_failure_fn start_failure, | |
1852 | task_finished_fn task_finished, void *pp_cb, | |
1853 | const char *tr2_category, const char *tr2_label) | |
1854 | { | |
1855 | int result; | |
1856 | ||
1857 | trace2_region_enter_printf(tr2_category, tr2_label, NULL, "max:%d", | |
1858 | ((n < 1) ? online_cpus() : n)); | |
1859 | ||
1860 | result = run_processes_parallel(n, get_next_task, start_failure, | |
1861 | task_finished, pp_cb); | |
1862 | ||
1863 | trace2_region_leave(tr2_category, tr2_label, NULL); | |
1864 | ||
1865 | return result; | |
1866 | } |