| 1 | #define DISABLE_SIGN_COMPARE_WARNINGS |
| 2 | |
| 3 | #include "git-compat-util.h" |
| 4 | #include "run-command.h" |
| 5 | #include "environment.h" |
| 6 | #include "exec-cmd.h" |
| 7 | #include "gettext.h" |
| 8 | #include "sigchain.h" |
| 9 | #include "strvec.h" |
| 10 | #include "symlinks.h" |
| 11 | #include "thread-utils.h" |
| 12 | #include "strbuf.h" |
| 13 | #include "string-list.h" |
| 14 | #include "trace.h" |
| 15 | #include "trace2.h" |
| 16 | #include "quote.h" |
| 17 | #include "config.h" |
| 18 | #include "packfile.h" |
| 19 | #include "compat/nonblock.h" |
| 20 | |
| 21 | void child_process_init(struct child_process *child) |
| 22 | { |
| 23 | struct child_process blank = CHILD_PROCESS_INIT; |
| 24 | memcpy(child, &blank, sizeof(*child)); |
| 25 | } |
| 26 | |
| 27 | void child_process_clear(struct child_process *child) |
| 28 | { |
| 29 | strvec_clear(&child->args); |
| 30 | strvec_clear(&child->env); |
| 31 | } |
| 32 | |
| 33 | struct child_to_clean { |
| 34 | pid_t pid; |
| 35 | struct child_process *process; |
| 36 | struct child_to_clean *next; |
| 37 | }; |
| 38 | static struct child_to_clean *children_to_clean; |
| 39 | static int installed_child_cleanup_handler; |
| 40 | |
| 41 | static void cleanup_children(int sig, int in_signal) |
| 42 | { |
| 43 | struct child_to_clean *children_to_wait_for = NULL; |
| 44 | |
| 45 | while (children_to_clean) { |
| 46 | struct child_to_clean *p = children_to_clean; |
| 47 | children_to_clean = p->next; |
| 48 | |
| 49 | if (p->process && !in_signal) { |
| 50 | struct child_process *process = p->process; |
| 51 | if (process->clean_on_exit_handler) { |
| 52 | trace_printf( |
| 53 | "trace: run_command: running exit handler for pid %" |
| 54 | PRIuMAX, (uintmax_t)p->pid |
| 55 | ); |
| 56 | process->clean_on_exit_handler(process); |
| 57 | } |
| 58 | } |
| 59 | |
| 60 | kill(p->pid, sig); |
| 61 | |
| 62 | if (p->process && p->process->wait_after_clean) { |
| 63 | p->next = children_to_wait_for; |
| 64 | children_to_wait_for = p; |
| 65 | } else { |
| 66 | if (!in_signal) |
| 67 | free(p); |
| 68 | } |
| 69 | } |
| 70 | |
| 71 | while (children_to_wait_for) { |
| 72 | struct child_to_clean *p = children_to_wait_for; |
| 73 | children_to_wait_for = p->next; |
| 74 | |
| 75 | while (waitpid(p->pid, NULL, 0) < 0 && errno == EINTR) |
| 76 | ; /* spin waiting for process exit or error */ |
| 77 | |
| 78 | if (!in_signal) |
| 79 | free(p); |
| 80 | } |
| 81 | } |
| 82 | |
| 83 | static void cleanup_children_on_signal(int sig) |
| 84 | { |
| 85 | cleanup_children(sig, 1); |
| 86 | sigchain_pop(sig); |
| 87 | raise(sig); |
| 88 | } |
| 89 | |
| 90 | static void cleanup_children_on_exit(void) |
| 91 | { |
| 92 | cleanup_children(SIGTERM, 0); |
| 93 | } |
| 94 | |
| 95 | static void mark_child_for_cleanup(pid_t pid, struct child_process *process) |
| 96 | { |
| 97 | struct child_to_clean *p = xmalloc(sizeof(*p)); |
| 98 | p->pid = pid; |
| 99 | p->process = process; |
| 100 | p->next = children_to_clean; |
| 101 | children_to_clean = p; |
| 102 | |
| 103 | if (!installed_child_cleanup_handler) { |
| 104 | atexit(cleanup_children_on_exit); |
| 105 | sigchain_push_common(cleanup_children_on_signal); |
| 106 | installed_child_cleanup_handler = 1; |
| 107 | } |
| 108 | } |
| 109 | |
| 110 | static void clear_child_for_cleanup(pid_t pid) |
| 111 | { |
| 112 | struct child_to_clean **pp; |
| 113 | |
| 114 | for (pp = &children_to_clean; *pp; pp = &(*pp)->next) { |
| 115 | struct child_to_clean *clean_me = *pp; |
| 116 | |
| 117 | if (clean_me->pid == pid) { |
| 118 | *pp = clean_me->next; |
| 119 | free(clean_me); |
| 120 | return; |
| 121 | } |
| 122 | } |
| 123 | } |
| 124 | |
| 125 | static inline void close_pair(int fd[2]) |
| 126 | { |
| 127 | close(fd[0]); |
| 128 | close(fd[1]); |
| 129 | } |
| 130 | |
| 131 | int is_executable(const char *name) |
| 132 | { |
| 133 | struct stat st; |
| 134 | |
| 135 | if (stat(name, &st) || /* stat, not lstat */ |
| 136 | !S_ISREG(st.st_mode)) |
| 137 | return 0; |
| 138 | |
| 139 | #if defined(GIT_WINDOWS_NATIVE) |
| 140 | /* |
| 141 | * On Windows there is no executable bit. The file extension |
| 142 | * indicates whether it can be run as an executable, and Git |
| 143 | * has special-handling to detect scripts and launch them |
| 144 | * through the indicated script interpreter. We test for the |
| 145 | * file extension first because virus scanners may make |
| 146 | * it quite expensive to open many files. |
| 147 | */ |
| 148 | if (ends_with(name, ".exe")) |
| 149 | return S_IXUSR; |
| 150 | |
| 151 | { |
| 152 | /* |
| 153 | * Now that we know it does not have an executable extension, |
| 154 | * peek into the file instead. |
| 155 | */ |
| 156 | char buf[3] = { 0 }; |
| 157 | int n; |
| 158 | int fd = open(name, O_RDONLY); |
| 159 | st.st_mode &= ~S_IXUSR; |
| 160 | if (fd >= 0) { |
| 161 | n = read(fd, buf, 2); |
| 162 | if (n == 2) |
| 163 | /* look for a she-bang */ |
| 164 | if (!strcmp(buf, "#!")) |
| 165 | st.st_mode |= S_IXUSR; |
| 166 | close(fd); |
| 167 | } |
| 168 | } |
| 169 | #endif |
| 170 | return st.st_mode & S_IXUSR; |
| 171 | } |
| 172 | |
| 173 | #ifndef locate_in_PATH |
| 174 | /* |
| 175 | * Search $PATH for a command. This emulates the path search that |
| 176 | * execvp would perform, without actually executing the command so it |
| 177 | * can be used before fork() to prepare to run a command using |
| 178 | * execve() or after execvp() to diagnose why it failed. |
| 179 | * |
| 180 | * The caller should ensure that file contains no directory |
| 181 | * separators. |
| 182 | * |
| 183 | * Returns the path to the command, as found in $PATH or NULL if the |
| 184 | * command could not be found. The caller inherits ownership of the memory |
| 185 | * used to store the resultant path. |
| 186 | * |
| 187 | * This should not be used on Windows, where the $PATH search rules |
| 188 | * are more complicated (e.g., a search for "foo" should find |
| 189 | * "foo.exe"). |
| 190 | */ |
| 191 | static char *locate_in_PATH(const char *file) |
| 192 | { |
| 193 | const char *p = getenv("PATH"); |
| 194 | struct strbuf buf = STRBUF_INIT; |
| 195 | |
| 196 | if (!p || !*p) |
| 197 | return NULL; |
| 198 | |
| 199 | while (1) { |
| 200 | const char *end = strchrnul(p, ':'); |
| 201 | |
| 202 | strbuf_reset(&buf); |
| 203 | |
| 204 | /* POSIX specifies an empty entry as the current directory. */ |
| 205 | if (end != p) { |
| 206 | strbuf_add(&buf, p, end - p); |
| 207 | strbuf_addch(&buf, '/'); |
| 208 | } |
| 209 | strbuf_addstr(&buf, file); |
| 210 | |
| 211 | if (is_executable(buf.buf)) |
| 212 | return strbuf_detach(&buf, NULL); |
| 213 | |
| 214 | if (!*end) |
| 215 | break; |
| 216 | p = end + 1; |
| 217 | } |
| 218 | |
| 219 | strbuf_release(&buf); |
| 220 | return NULL; |
| 221 | } |
| 222 | #endif |
| 223 | |
| 224 | int exists_in_PATH(const char *command) |
| 225 | { |
| 226 | char *r = locate_in_PATH(command); |
| 227 | int found = r != NULL; |
| 228 | free(r); |
| 229 | return found; |
| 230 | } |
| 231 | |
| 232 | int sane_execvp(const char *file, char * const argv[]) |
| 233 | { |
| 234 | #ifndef GIT_WINDOWS_NATIVE |
| 235 | /* |
| 236 | * execvp() doesn't return, so we all we can do is tell trace2 |
| 237 | * what we are about to do and let it leave a hint in the log |
| 238 | * (unless of course the execvp() fails). |
| 239 | * |
| 240 | * we skip this for Windows because the compat layer already |
| 241 | * has to emulate the execvp() call anyway. |
| 242 | */ |
| 243 | int exec_id = trace2_exec(file, (const char **)argv); |
| 244 | #endif |
| 245 | |
| 246 | if (!execvp(file, argv)) |
| 247 | return 0; /* cannot happen ;-) */ |
| 248 | |
| 249 | #ifndef GIT_WINDOWS_NATIVE |
| 250 | { |
| 251 | int ec = errno; |
| 252 | trace2_exec_result(exec_id, ec); |
| 253 | errno = ec; |
| 254 | } |
| 255 | #endif |
| 256 | |
| 257 | /* |
| 258 | * When a command can't be found because one of the directories |
| 259 | * listed in $PATH is unsearchable, execvp reports EACCES, but |
| 260 | * careful usability testing (read: analysis of occasional bug |
| 261 | * reports) reveals that "No such file or directory" is more |
| 262 | * intuitive. |
| 263 | * |
| 264 | * We avoid commands with "/", because execvp will not do $PATH |
| 265 | * lookups in that case. |
| 266 | * |
| 267 | * The reassignment of EACCES to errno looks like a no-op below, |
| 268 | * but we need to protect against exists_in_PATH overwriting errno. |
| 269 | */ |
| 270 | if (errno == EACCES && !strchr(file, '/')) |
| 271 | errno = exists_in_PATH(file) ? EACCES : ENOENT; |
| 272 | else if (errno == ENOTDIR && !strchr(file, '/')) |
| 273 | errno = ENOENT; |
| 274 | return -1; |
| 275 | } |
| 276 | |
| 277 | char *git_shell_path(void) |
| 278 | { |
| 279 | #ifndef GIT_WINDOWS_NATIVE |
| 280 | return xstrdup(SHELL_PATH); |
| 281 | #else |
| 282 | char *p = locate_in_PATH("sh"); |
| 283 | convert_slashes(p); |
| 284 | return p; |
| 285 | #endif |
| 286 | } |
| 287 | |
| 288 | static const char **prepare_shell_cmd(struct strvec *out, const char **argv) |
| 289 | { |
| 290 | if (!argv[0]) |
| 291 | BUG("shell command is empty"); |
| 292 | |
| 293 | if (strcspn(argv[0], "|&;<>()$`\\\"' \t\n*?[#~=%") != strlen(argv[0])) { |
| 294 | strvec_push_nodup(out, git_shell_path()); |
| 295 | strvec_push(out, "-c"); |
| 296 | |
| 297 | /* |
| 298 | * If we have no extra arguments, we do not even need to |
| 299 | * bother with the "$@" magic. |
| 300 | */ |
| 301 | if (!argv[1]) |
| 302 | strvec_push(out, argv[0]); |
| 303 | else |
| 304 | strvec_pushf(out, "%s \"$@\"", argv[0]); |
| 305 | } |
| 306 | |
| 307 | strvec_pushv(out, argv); |
| 308 | return out->v; |
| 309 | } |
| 310 | |
| 311 | #ifndef GIT_WINDOWS_NATIVE |
| 312 | static int child_notifier = -1; |
| 313 | |
| 314 | enum child_errcode { |
| 315 | CHILD_ERR_CHDIR, |
| 316 | CHILD_ERR_DUP2, |
| 317 | CHILD_ERR_CLOSE, |
| 318 | CHILD_ERR_SIGPROCMASK, |
| 319 | CHILD_ERR_SILENT, |
| 320 | CHILD_ERR_ERRNO |
| 321 | }; |
| 322 | |
| 323 | struct child_err { |
| 324 | enum child_errcode err; |
| 325 | int syserr; /* errno */ |
| 326 | }; |
| 327 | |
| 328 | static void child_die(enum child_errcode err) |
| 329 | { |
| 330 | struct child_err buf; |
| 331 | |
| 332 | buf.err = err; |
| 333 | buf.syserr = errno; |
| 334 | |
| 335 | /* write(2) on buf smaller than PIPE_BUF (min 512) is atomic: */ |
| 336 | xwrite(child_notifier, &buf, sizeof(buf)); |
| 337 | _exit(1); |
| 338 | } |
| 339 | |
| 340 | static void child_dup2(int fd, int to) |
| 341 | { |
| 342 | if (dup2(fd, to) < 0) |
| 343 | child_die(CHILD_ERR_DUP2); |
| 344 | } |
| 345 | |
| 346 | static void child_close(int fd) |
| 347 | { |
| 348 | if (close(fd)) |
| 349 | child_die(CHILD_ERR_CLOSE); |
| 350 | } |
| 351 | |
| 352 | static void child_close_pair(int fd[2]) |
| 353 | { |
| 354 | child_close(fd[0]); |
| 355 | child_close(fd[1]); |
| 356 | } |
| 357 | |
| 358 | static void child_error_fn(const char *err UNUSED, va_list params UNUSED) |
| 359 | { |
| 360 | const char msg[] = "error() should not be called in child\n"; |
| 361 | xwrite(2, msg, sizeof(msg) - 1); |
| 362 | } |
| 363 | |
| 364 | static void child_warn_fn(const char *err UNUSED, va_list params UNUSED) |
| 365 | { |
| 366 | const char msg[] = "warn() should not be called in child\n"; |
| 367 | xwrite(2, msg, sizeof(msg) - 1); |
| 368 | } |
| 369 | |
| 370 | static void NORETURN child_die_fn(const char *err UNUSED, va_list params UNUSED) |
| 371 | { |
| 372 | const char msg[] = "die() should not be called in child\n"; |
| 373 | xwrite(2, msg, sizeof(msg) - 1); |
| 374 | _exit(2); |
| 375 | } |
| 376 | |
| 377 | /* this runs in the parent process */ |
| 378 | static void child_err_spew(struct child_process *cmd, struct child_err *cerr) |
| 379 | { |
| 380 | static void (*old_errfn)(const char *err, va_list params); |
| 381 | report_fn die_message_routine = get_die_message_routine(); |
| 382 | |
| 383 | old_errfn = get_error_routine(); |
| 384 | set_error_routine(die_message_routine); |
| 385 | errno = cerr->syserr; |
| 386 | |
| 387 | switch (cerr->err) { |
| 388 | case CHILD_ERR_CHDIR: |
| 389 | error_errno("exec '%s': cd to '%s' failed", |
| 390 | cmd->args.v[0], cmd->dir); |
| 391 | break; |
| 392 | case CHILD_ERR_DUP2: |
| 393 | error_errno("dup2() in child failed"); |
| 394 | break; |
| 395 | case CHILD_ERR_CLOSE: |
| 396 | error_errno("close() in child failed"); |
| 397 | break; |
| 398 | case CHILD_ERR_SIGPROCMASK: |
| 399 | error_errno("sigprocmask failed restoring signals"); |
| 400 | break; |
| 401 | case CHILD_ERR_SILENT: |
| 402 | break; |
| 403 | case CHILD_ERR_ERRNO: |
| 404 | error_errno("cannot exec '%s'", cmd->args.v[0]); |
| 405 | break; |
| 406 | } |
| 407 | set_error_routine(old_errfn); |
| 408 | } |
| 409 | |
| 410 | static int prepare_cmd(struct strvec *out, const struct child_process *cmd) |
| 411 | { |
| 412 | if (!cmd->args.v[0]) |
| 413 | BUG("command is empty"); |
| 414 | |
| 415 | /* |
| 416 | * Add SHELL_PATH so in the event exec fails with ENOEXEC we can |
| 417 | * attempt to interpret the command with 'sh'. |
| 418 | */ |
| 419 | strvec_push(out, SHELL_PATH); |
| 420 | |
| 421 | if (cmd->git_cmd) { |
| 422 | prepare_git_cmd(out, cmd->args.v); |
| 423 | } else if (cmd->use_shell) { |
| 424 | prepare_shell_cmd(out, cmd->args.v); |
| 425 | } else { |
| 426 | strvec_pushv(out, cmd->args.v); |
| 427 | } |
| 428 | |
| 429 | /* |
| 430 | * If there are no dir separator characters in the command then perform |
| 431 | * a path lookup and use the resolved path as the command to exec. If |
| 432 | * there are dir separator characters, we have exec attempt to invoke |
| 433 | * the command directly. |
| 434 | */ |
| 435 | if (!has_dir_sep(out->v[1])) { |
| 436 | char *program = locate_in_PATH(out->v[1]); |
| 437 | if (program) { |
| 438 | free((char *)out->v[1]); |
| 439 | out->v[1] = program; |
| 440 | } else { |
| 441 | strvec_clear(out); |
| 442 | errno = ENOENT; |
| 443 | return -1; |
| 444 | } |
| 445 | } |
| 446 | |
| 447 | return 0; |
| 448 | } |
| 449 | |
| 450 | static char **prep_childenv(const char *const *deltaenv) |
| 451 | { |
| 452 | extern char **environ; |
| 453 | char **childenv; |
| 454 | struct string_list env = STRING_LIST_INIT_DUP; |
| 455 | struct strbuf key = STRBUF_INIT; |
| 456 | const char *const *p; |
| 457 | int i; |
| 458 | |
| 459 | /* Construct a sorted string list consisting of the current environ */ |
| 460 | for (p = (const char *const *) environ; p && *p; p++) { |
| 461 | const char *equals = strchr(*p, '='); |
| 462 | |
| 463 | if (equals) { |
| 464 | strbuf_reset(&key); |
| 465 | strbuf_add(&key, *p, equals - *p); |
| 466 | string_list_append(&env, key.buf)->util = (void *) *p; |
| 467 | } else { |
| 468 | string_list_append(&env, *p)->util = (void *) *p; |
| 469 | } |
| 470 | } |
| 471 | string_list_sort(&env); |
| 472 | |
| 473 | /* Merge in 'deltaenv' with the current environ */ |
| 474 | for (p = deltaenv; p && *p; p++) { |
| 475 | const char *equals = strchr(*p, '='); |
| 476 | |
| 477 | if (equals) { |
| 478 | /* ('key=value'), insert or replace entry */ |
| 479 | strbuf_reset(&key); |
| 480 | strbuf_add(&key, *p, equals - *p); |
| 481 | string_list_insert(&env, key.buf)->util = (void *) *p; |
| 482 | } else { |
| 483 | /* otherwise ('key') remove existing entry */ |
| 484 | string_list_remove(&env, *p, 0); |
| 485 | } |
| 486 | } |
| 487 | |
| 488 | /* Create an array of 'char *' to be used as the childenv */ |
| 489 | ALLOC_ARRAY(childenv, env.nr + 1); |
| 490 | for (i = 0; i < env.nr; i++) |
| 491 | childenv[i] = env.items[i].util; |
| 492 | childenv[env.nr] = NULL; |
| 493 | |
| 494 | string_list_clear(&env, 0); |
| 495 | strbuf_release(&key); |
| 496 | return childenv; |
| 497 | } |
| 498 | |
| 499 | struct atfork_state { |
| 500 | #ifndef NO_PTHREADS |
| 501 | int cs; |
| 502 | #endif |
| 503 | sigset_t old; |
| 504 | }; |
| 505 | |
| 506 | #define CHECK_BUG(err, msg) \ |
| 507 | do { \ |
| 508 | int e = (err); \ |
| 509 | if (e) \ |
| 510 | BUG("%s: %s", msg, strerror(e)); \ |
| 511 | } while(0) |
| 512 | |
| 513 | static void atfork_prepare(struct atfork_state *as) |
| 514 | { |
| 515 | sigset_t all; |
| 516 | |
| 517 | /* |
| 518 | * POSIX says sigfillset() can fail, but an overly clever |
| 519 | * compiler can see through the header files and decide |
| 520 | * it cannot fail on a particular platform it is compiling for, |
| 521 | * triggering -Wunreachable-code false positive. |
| 522 | */ |
| 523 | if (NOT_CONSTANT(sigfillset(&all))) |
| 524 | die_errno("sigfillset"); |
| 525 | #ifdef NO_PTHREADS |
| 526 | if (sigprocmask(SIG_SETMASK, &all, &as->old)) |
| 527 | die_errno("sigprocmask"); |
| 528 | #else |
| 529 | CHECK_BUG(pthread_sigmask(SIG_SETMASK, &all, &as->old), |
| 530 | "blocking all signals"); |
| 531 | CHECK_BUG(pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &as->cs), |
| 532 | "disabling cancellation"); |
| 533 | #endif |
| 534 | } |
| 535 | |
| 536 | static void atfork_parent(struct atfork_state *as) |
| 537 | { |
| 538 | #ifdef NO_PTHREADS |
| 539 | if (sigprocmask(SIG_SETMASK, &as->old, NULL)) |
| 540 | die_errno("sigprocmask"); |
| 541 | #else |
| 542 | CHECK_BUG(pthread_setcancelstate(as->cs, NULL), |
| 543 | "re-enabling cancellation"); |
| 544 | CHECK_BUG(pthread_sigmask(SIG_SETMASK, &as->old, NULL), |
| 545 | "restoring signal mask"); |
| 546 | #endif |
| 547 | } |
| 548 | |
| 549 | #endif /* GIT_WINDOWS_NATIVE */ |
| 550 | |
| 551 | static inline void set_cloexec(int fd) |
| 552 | { |
| 553 | int flags = fcntl(fd, F_GETFD); |
| 554 | if (flags >= 0) |
| 555 | fcntl(fd, F_SETFD, flags | FD_CLOEXEC); |
| 556 | } |
| 557 | |
| 558 | static int wait_or_whine(pid_t pid, const char *argv0, int in_signal) |
| 559 | { |
| 560 | int status, code = -1; |
| 561 | pid_t waiting; |
| 562 | int failed_errno = 0; |
| 563 | |
| 564 | while ((waiting = waitpid(pid, &status, 0)) < 0 && errno == EINTR) |
| 565 | ; /* nothing */ |
| 566 | |
| 567 | if (waiting < 0) { |
| 568 | failed_errno = errno; |
| 569 | if (!in_signal) |
| 570 | error_errno("waitpid for %s failed", argv0); |
| 571 | } else if (waiting != pid) { |
| 572 | if (!in_signal) |
| 573 | error("waitpid is confused (%s)", argv0); |
| 574 | } else if (WIFSIGNALED(status)) { |
| 575 | code = WTERMSIG(status); |
| 576 | if (!in_signal && code != SIGINT && code != SIGQUIT && code != SIGPIPE) |
| 577 | error("%s died of signal %d", argv0, code); |
| 578 | /* |
| 579 | * This return value is chosen so that code & 0xff |
| 580 | * mimics the exit code that a POSIX shell would report for |
| 581 | * a program that died from this signal. |
| 582 | */ |
| 583 | code += 128; |
| 584 | } else if (WIFEXITED(status)) { |
| 585 | code = WEXITSTATUS(status); |
| 586 | } else { |
| 587 | if (!in_signal) |
| 588 | error("waitpid is confused (%s)", argv0); |
| 589 | } |
| 590 | |
| 591 | if (!in_signal) |
| 592 | clear_child_for_cleanup(pid); |
| 593 | |
| 594 | errno = failed_errno; |
| 595 | return code; |
| 596 | } |
| 597 | |
| 598 | static void trace_add_env(struct strbuf *dst, const char *const *deltaenv) |
| 599 | { |
| 600 | struct string_list envs = STRING_LIST_INIT_DUP; |
| 601 | const char *const *e; |
| 602 | int i; |
| 603 | int printed_unset = 0; |
| 604 | |
| 605 | /* Last one wins, see run-command.c:prep_childenv() for context */ |
| 606 | for (e = deltaenv; e && *e; e++) { |
| 607 | struct strbuf key = STRBUF_INIT; |
| 608 | const char *equals = strchr(*e, '='); |
| 609 | |
| 610 | if (equals) { |
| 611 | strbuf_add(&key, *e, equals - *e); |
| 612 | string_list_insert(&envs, key.buf)->util = (void *)(equals + 1); |
| 613 | } else { |
| 614 | string_list_insert(&envs, *e)->util = NULL; |
| 615 | } |
| 616 | strbuf_release(&key); |
| 617 | } |
| 618 | |
| 619 | /* "unset X Y...;" */ |
| 620 | for (i = 0; i < envs.nr; i++) { |
| 621 | const char *var = envs.items[i].string; |
| 622 | const char *val = envs.items[i].util; |
| 623 | |
| 624 | if (val || !getenv(var)) |
| 625 | continue; |
| 626 | |
| 627 | if (!printed_unset) { |
| 628 | strbuf_addstr(dst, " unset"); |
| 629 | printed_unset = 1; |
| 630 | } |
| 631 | strbuf_addf(dst, " %s", var); |
| 632 | } |
| 633 | if (printed_unset) |
| 634 | strbuf_addch(dst, ';'); |
| 635 | |
| 636 | /* ... followed by "A=B C=D ..." */ |
| 637 | for (i = 0; i < envs.nr; i++) { |
| 638 | const char *var = envs.items[i].string; |
| 639 | const char *val = envs.items[i].util; |
| 640 | const char *oldval; |
| 641 | |
| 642 | if (!val) |
| 643 | continue; |
| 644 | |
| 645 | oldval = getenv(var); |
| 646 | if (oldval && !strcmp(val, oldval)) |
| 647 | continue; |
| 648 | |
| 649 | strbuf_addf(dst, " %s=", var); |
| 650 | sq_quote_buf_pretty(dst, val); |
| 651 | } |
| 652 | string_list_clear(&envs, 0); |
| 653 | } |
| 654 | |
| 655 | static void trace_run_command(const struct child_process *cp) |
| 656 | { |
| 657 | struct strbuf buf = STRBUF_INIT; |
| 658 | |
| 659 | if (!trace_want(&trace_default_key)) |
| 660 | return; |
| 661 | |
| 662 | strbuf_addstr(&buf, "trace: run_command:"); |
| 663 | if (cp->dir) { |
| 664 | strbuf_addstr(&buf, " cd "); |
| 665 | sq_quote_buf_pretty(&buf, cp->dir); |
| 666 | strbuf_addch(&buf, ';'); |
| 667 | } |
| 668 | trace_add_env(&buf, cp->env.v); |
| 669 | if (cp->git_cmd) |
| 670 | strbuf_addstr(&buf, " git"); |
| 671 | sq_quote_argv_pretty(&buf, cp->args.v); |
| 672 | |
| 673 | trace_printf("%s", buf.buf); |
| 674 | strbuf_release(&buf); |
| 675 | } |
| 676 | |
| 677 | int start_command(struct child_process *cmd) |
| 678 | { |
| 679 | int need_in, need_out, need_err; |
| 680 | int fdin[2], fdout[2], fderr[2]; |
| 681 | int failed_errno; |
| 682 | const char *str; |
| 683 | |
| 684 | /* |
| 685 | * In case of errors we must keep the promise to close FDs |
| 686 | * that have been passed in via ->in and ->out. |
| 687 | */ |
| 688 | |
| 689 | need_in = !cmd->no_stdin && cmd->in < 0; |
| 690 | if (need_in) { |
| 691 | if (pipe(fdin) < 0) { |
| 692 | failed_errno = errno; |
| 693 | if (cmd->out > 0) |
| 694 | close(cmd->out); |
| 695 | str = "standard input"; |
| 696 | goto fail_pipe; |
| 697 | } |
| 698 | cmd->in = fdin[1]; |
| 699 | } |
| 700 | |
| 701 | need_out = !cmd->no_stdout |
| 702 | && !cmd->stdout_to_stderr |
| 703 | && cmd->out < 0; |
| 704 | if (need_out) { |
| 705 | if (pipe(fdout) < 0) { |
| 706 | failed_errno = errno; |
| 707 | if (need_in) |
| 708 | close_pair(fdin); |
| 709 | else if (cmd->in) |
| 710 | close(cmd->in); |
| 711 | str = "standard output"; |
| 712 | goto fail_pipe; |
| 713 | } |
| 714 | cmd->out = fdout[0]; |
| 715 | } |
| 716 | |
| 717 | need_err = !cmd->no_stderr && cmd->err < 0; |
| 718 | if (need_err) { |
| 719 | if (pipe(fderr) < 0) { |
| 720 | failed_errno = errno; |
| 721 | if (need_in) |
| 722 | close_pair(fdin); |
| 723 | else if (cmd->in) |
| 724 | close(cmd->in); |
| 725 | if (need_out) |
| 726 | close_pair(fdout); |
| 727 | else if (cmd->out) |
| 728 | close(cmd->out); |
| 729 | str = "standard error"; |
| 730 | fail_pipe: |
| 731 | error("cannot create %s pipe for %s: %s", |
| 732 | str, cmd->args.v[0], strerror(failed_errno)); |
| 733 | child_process_clear(cmd); |
| 734 | errno = failed_errno; |
| 735 | return -1; |
| 736 | } |
| 737 | cmd->err = fderr[0]; |
| 738 | } |
| 739 | |
| 740 | trace2_child_start(cmd); |
| 741 | trace_run_command(cmd); |
| 742 | |
| 743 | fflush(NULL); |
| 744 | |
| 745 | if (cmd->odb_to_close) |
| 746 | odb_close(cmd->odb_to_close); |
| 747 | |
| 748 | #ifndef GIT_WINDOWS_NATIVE |
| 749 | { |
| 750 | int notify_pipe[2]; |
| 751 | int null_fd = -1; |
| 752 | char **childenv; |
| 753 | struct strvec argv = STRVEC_INIT; |
| 754 | struct child_err cerr; |
| 755 | struct atfork_state as; |
| 756 | |
| 757 | if (prepare_cmd(&argv, cmd) < 0) { |
| 758 | failed_errno = errno; |
| 759 | cmd->pid = -1; |
| 760 | if (!cmd->silent_exec_failure) |
| 761 | error_errno("cannot run %s", cmd->args.v[0]); |
| 762 | goto end_of_spawn; |
| 763 | } |
| 764 | |
| 765 | trace_argv_printf(&argv.v[1], "trace: start_command:"); |
| 766 | |
| 767 | if (pipe(notify_pipe)) |
| 768 | notify_pipe[0] = notify_pipe[1] = -1; |
| 769 | |
| 770 | if (cmd->no_stdin || cmd->no_stdout || cmd->no_stderr) { |
| 771 | null_fd = xopen("/dev/null", O_RDWR | O_CLOEXEC); |
| 772 | set_cloexec(null_fd); |
| 773 | } |
| 774 | |
| 775 | childenv = prep_childenv(cmd->env.v); |
| 776 | atfork_prepare(&as); |
| 777 | |
| 778 | /* |
| 779 | * NOTE: In order to prevent deadlocking when using threads special |
| 780 | * care should be taken with the function calls made in between the |
| 781 | * fork() and exec() calls. No calls should be made to functions which |
| 782 | * require acquiring a lock (e.g. malloc) as the lock could have been |
| 783 | * held by another thread at the time of forking, causing the lock to |
| 784 | * never be released in the child process. This means only |
| 785 | * Async-Signal-Safe functions are permitted in the child. |
| 786 | */ |
| 787 | cmd->pid = fork(); |
| 788 | failed_errno = errno; |
| 789 | if (!cmd->pid) { |
| 790 | int sig; |
| 791 | /* |
| 792 | * Ensure the default die/error/warn routines do not get |
| 793 | * called, they can take stdio locks and malloc. |
| 794 | */ |
| 795 | set_die_routine(child_die_fn); |
| 796 | set_error_routine(child_error_fn); |
| 797 | set_warn_routine(child_warn_fn); |
| 798 | |
| 799 | close(notify_pipe[0]); |
| 800 | set_cloexec(notify_pipe[1]); |
| 801 | child_notifier = notify_pipe[1]; |
| 802 | |
| 803 | if (cmd->no_stdin) |
| 804 | child_dup2(null_fd, 0); |
| 805 | else if (need_in) { |
| 806 | child_dup2(fdin[0], 0); |
| 807 | child_close_pair(fdin); |
| 808 | } else if (cmd->in) { |
| 809 | child_dup2(cmd->in, 0); |
| 810 | child_close(cmd->in); |
| 811 | } |
| 812 | |
| 813 | if (cmd->no_stderr) |
| 814 | child_dup2(null_fd, 2); |
| 815 | else if (need_err) { |
| 816 | child_dup2(fderr[1], 2); |
| 817 | child_close_pair(fderr); |
| 818 | } else if (cmd->err > 1) { |
| 819 | child_dup2(cmd->err, 2); |
| 820 | child_close(cmd->err); |
| 821 | } |
| 822 | |
| 823 | if (cmd->no_stdout) |
| 824 | child_dup2(null_fd, 1); |
| 825 | else if (cmd->stdout_to_stderr) |
| 826 | child_dup2(2, 1); |
| 827 | else if (need_out) { |
| 828 | child_dup2(fdout[1], 1); |
| 829 | child_close_pair(fdout); |
| 830 | } else if (cmd->out > 1) { |
| 831 | child_dup2(cmd->out, 1); |
| 832 | child_close(cmd->out); |
| 833 | } |
| 834 | |
| 835 | if (cmd->close_fd_above_stderr) { |
| 836 | long max_fd = sysconf(_SC_OPEN_MAX); |
| 837 | int fd; |
| 838 | if (max_fd < 0 || max_fd > 4096) |
| 839 | max_fd = 4096; |
| 840 | for (fd = 3; fd < max_fd; fd++) { |
| 841 | if (fd != child_notifier) |
| 842 | close(fd); |
| 843 | } |
| 844 | } |
| 845 | |
| 846 | if (cmd->dir && chdir(cmd->dir)) |
| 847 | child_die(CHILD_ERR_CHDIR); |
| 848 | |
| 849 | /* |
| 850 | * restore default signal handlers here, in case |
| 851 | * we catch a signal right before execve below |
| 852 | */ |
| 853 | for (sig = 1; sig < NSIG; sig++) { |
| 854 | /* ignored signals get reset to SIG_DFL on execve */ |
| 855 | if (signal(sig, SIG_DFL) == SIG_IGN) |
| 856 | signal(sig, SIG_IGN); |
| 857 | } |
| 858 | |
| 859 | if (sigprocmask(SIG_SETMASK, &as.old, NULL) != 0) |
| 860 | child_die(CHILD_ERR_SIGPROCMASK); |
| 861 | |
| 862 | /* |
| 863 | * Attempt to exec using the command and arguments starting at |
| 864 | * argv.argv[1]. argv.argv[0] contains SHELL_PATH which will |
| 865 | * be used in the event exec failed with ENOEXEC at which point |
| 866 | * we will try to interpret the command using 'sh'. |
| 867 | */ |
| 868 | execve(argv.v[1], (char *const *) argv.v + 1, |
| 869 | (char *const *) childenv); |
| 870 | if (errno == ENOEXEC) |
| 871 | execve(argv.v[0], (char *const *) argv.v, |
| 872 | (char *const *) childenv); |
| 873 | |
| 874 | if (cmd->silent_exec_failure && errno == ENOENT) |
| 875 | child_die(CHILD_ERR_SILENT); |
| 876 | child_die(CHILD_ERR_ERRNO); |
| 877 | } |
| 878 | atfork_parent(&as); |
| 879 | if (cmd->pid < 0) |
| 880 | error_errno("cannot fork() for %s", cmd->args.v[0]); |
| 881 | else if (cmd->clean_on_exit) |
| 882 | mark_child_for_cleanup(cmd->pid, cmd); |
| 883 | |
| 884 | /* |
| 885 | * Wait for child's exec. If the exec succeeds (or if fork() |
| 886 | * failed), EOF is seen immediately by the parent. Otherwise, the |
| 887 | * child process sends a child_err struct. |
| 888 | * Note that use of this infrastructure is completely advisory, |
| 889 | * therefore, we keep error checks minimal. |
| 890 | */ |
| 891 | close(notify_pipe[1]); |
| 892 | if (xread(notify_pipe[0], &cerr, sizeof(cerr)) == sizeof(cerr)) { |
| 893 | /* |
| 894 | * At this point we know that fork() succeeded, but exec() |
| 895 | * failed. Errors have been reported to our stderr. |
| 896 | */ |
| 897 | wait_or_whine(cmd->pid, cmd->args.v[0], 0); |
| 898 | child_err_spew(cmd, &cerr); |
| 899 | failed_errno = errno; |
| 900 | cmd->pid = -1; |
| 901 | } |
| 902 | close(notify_pipe[0]); |
| 903 | |
| 904 | if (null_fd >= 0) |
| 905 | close(null_fd); |
| 906 | strvec_clear(&argv); |
| 907 | free(childenv); |
| 908 | } |
| 909 | end_of_spawn: |
| 910 | |
| 911 | #else |
| 912 | { |
| 913 | int fhin = 0, fhout = 1, fherr = 2; |
| 914 | const char **sargv = cmd->args.v; |
| 915 | struct strvec nargv = STRVEC_INIT; |
| 916 | |
| 917 | if (cmd->no_stdin) |
| 918 | fhin = open("/dev/null", O_RDWR); |
| 919 | else if (need_in) |
| 920 | fhin = dup(fdin[0]); |
| 921 | else if (cmd->in) |
| 922 | fhin = dup(cmd->in); |
| 923 | |
| 924 | if (cmd->no_stderr) |
| 925 | fherr = open("/dev/null", O_RDWR); |
| 926 | else if (need_err) |
| 927 | fherr = dup(fderr[1]); |
| 928 | else if (cmd->err > 2) |
| 929 | fherr = dup(cmd->err); |
| 930 | |
| 931 | if (cmd->no_stdout) |
| 932 | fhout = open("/dev/null", O_RDWR); |
| 933 | else if (cmd->stdout_to_stderr) |
| 934 | fhout = dup(fherr); |
| 935 | else if (need_out) |
| 936 | fhout = dup(fdout[1]); |
| 937 | else if (cmd->out > 1) |
| 938 | fhout = dup(cmd->out); |
| 939 | |
| 940 | if (cmd->git_cmd) |
| 941 | cmd->args.v = prepare_git_cmd(&nargv, sargv); |
| 942 | else if (cmd->use_shell) |
| 943 | cmd->args.v = prepare_shell_cmd(&nargv, sargv); |
| 944 | |
| 945 | trace_argv_printf(cmd->args.v, "trace: start_command:"); |
| 946 | cmd->pid = mingw_spawnvpe(cmd->args.v[0], cmd->args.v, |
| 947 | (char**) cmd->env.v, |
| 948 | cmd->dir, fhin, fhout, fherr); |
| 949 | failed_errno = errno; |
| 950 | if (cmd->pid < 0 && (!cmd->silent_exec_failure || errno != ENOENT)) |
| 951 | error_errno("cannot spawn %s", cmd->args.v[0]); |
| 952 | if (cmd->clean_on_exit && cmd->pid >= 0) |
| 953 | mark_child_for_cleanup(cmd->pid, cmd); |
| 954 | |
| 955 | strvec_clear(&nargv); |
| 956 | cmd->args.v = sargv; |
| 957 | if (fhin != 0) |
| 958 | close(fhin); |
| 959 | if (fhout != 1) |
| 960 | close(fhout); |
| 961 | if (fherr != 2) |
| 962 | close(fherr); |
| 963 | } |
| 964 | #endif |
| 965 | |
| 966 | if (cmd->pid < 0) { |
| 967 | trace2_child_exit(cmd, -1); |
| 968 | |
| 969 | if (need_in) |
| 970 | close_pair(fdin); |
| 971 | else if (cmd->in) |
| 972 | close(cmd->in); |
| 973 | if (need_out) |
| 974 | close_pair(fdout); |
| 975 | else if (cmd->out) |
| 976 | close(cmd->out); |
| 977 | if (need_err) |
| 978 | close_pair(fderr); |
| 979 | else if (cmd->err) |
| 980 | close(cmd->err); |
| 981 | child_process_clear(cmd); |
| 982 | errno = failed_errno; |
| 983 | return -1; |
| 984 | } |
| 985 | |
| 986 | if (need_in) |
| 987 | close(fdin[0]); |
| 988 | else if (cmd->in) |
| 989 | close(cmd->in); |
| 990 | |
| 991 | if (need_out) |
| 992 | close(fdout[1]); |
| 993 | else if (cmd->out) |
| 994 | close(cmd->out); |
| 995 | |
| 996 | if (need_err) |
| 997 | close(fderr[1]); |
| 998 | else if (cmd->err) |
| 999 | close(cmd->err); |
| 1000 | |
| 1001 | return 0; |
| 1002 | } |
| 1003 | |
| 1004 | int finish_command(struct child_process *cmd) |
| 1005 | { |
| 1006 | int ret = wait_or_whine(cmd->pid, cmd->args.v[0], 0); |
| 1007 | trace2_child_exit(cmd, ret); |
| 1008 | child_process_clear(cmd); |
| 1009 | invalidate_lstat_cache(); |
| 1010 | return ret; |
| 1011 | } |
| 1012 | |
| 1013 | int finish_command_in_signal(struct child_process *cmd) |
| 1014 | { |
| 1015 | int ret = wait_or_whine(cmd->pid, cmd->args.v[0], 1); |
| 1016 | if (ret != -1) |
| 1017 | trace2_child_exit(cmd, ret); |
| 1018 | return ret; |
| 1019 | } |
| 1020 | |
| 1021 | |
| 1022 | int run_command(struct child_process *cmd) |
| 1023 | { |
| 1024 | int code; |
| 1025 | |
| 1026 | if (cmd->out < 0 || cmd->err < 0) |
| 1027 | BUG("run_command with a pipe can cause deadlock"); |
| 1028 | |
| 1029 | code = start_command(cmd); |
| 1030 | if (code) |
| 1031 | return code; |
| 1032 | return finish_command(cmd); |
| 1033 | } |
| 1034 | |
| 1035 | #ifndef NO_PTHREADS |
| 1036 | static pthread_t main_thread; |
| 1037 | static int main_thread_set; |
| 1038 | static pthread_key_t async_key; |
| 1039 | static pthread_key_t async_die_counter; |
| 1040 | |
| 1041 | static void *run_thread(void *data) |
| 1042 | { |
| 1043 | struct async *async = data; |
| 1044 | intptr_t ret; |
| 1045 | |
| 1046 | if (async->isolate_sigpipe) { |
| 1047 | sigset_t mask; |
| 1048 | sigemptyset(&mask); |
| 1049 | sigaddset(&mask, SIGPIPE); |
| 1050 | if (pthread_sigmask(SIG_BLOCK, &mask, NULL)) { |
| 1051 | ret = error("unable to block SIGPIPE in async thread"); |
| 1052 | return (void *)ret; |
| 1053 | } |
| 1054 | } |
| 1055 | |
| 1056 | pthread_setspecific(async_key, async); |
| 1057 | ret = async->proc(async->proc_in, async->proc_out, async->data); |
| 1058 | return (void *)ret; |
| 1059 | } |
| 1060 | |
| 1061 | static NORETURN void die_async(const char *err, va_list params) |
| 1062 | { |
| 1063 | report_fn die_message_fn = get_die_message_routine(); |
| 1064 | |
| 1065 | die_message_fn(err, params); |
| 1066 | |
| 1067 | if (in_async()) { |
| 1068 | struct async *async = pthread_getspecific(async_key); |
| 1069 | if (async->proc_in >= 0) |
| 1070 | close(async->proc_in); |
| 1071 | if (async->proc_out >= 0) |
| 1072 | close(async->proc_out); |
| 1073 | pthread_exit((void *)128); |
| 1074 | } |
| 1075 | |
| 1076 | exit(128); |
| 1077 | } |
| 1078 | |
| 1079 | static int async_die_is_recursing(void) |
| 1080 | { |
| 1081 | void *ret = pthread_getspecific(async_die_counter); |
| 1082 | pthread_setspecific(async_die_counter, &async_die_counter); /* set to any non-NULL valid pointer */ |
| 1083 | return ret != NULL; |
| 1084 | } |
| 1085 | |
| 1086 | int in_async(void) |
| 1087 | { |
| 1088 | if (!main_thread_set) |
| 1089 | return 0; /* no asyncs started yet */ |
| 1090 | return !pthread_equal(main_thread, pthread_self()); |
| 1091 | } |
| 1092 | |
| 1093 | static void NORETURN async_exit(int code) |
| 1094 | { |
| 1095 | pthread_exit((void *)(intptr_t)code); |
| 1096 | } |
| 1097 | |
| 1098 | #else |
| 1099 | |
| 1100 | static struct { |
| 1101 | void (**handlers)(void); |
| 1102 | size_t nr; |
| 1103 | size_t alloc; |
| 1104 | } git_atexit_hdlrs; |
| 1105 | |
| 1106 | static int git_atexit_installed; |
| 1107 | |
| 1108 | static void git_atexit_dispatch(void) |
| 1109 | { |
| 1110 | size_t i; |
| 1111 | |
| 1112 | for (i=git_atexit_hdlrs.nr ; i ; i--) |
| 1113 | git_atexit_hdlrs.handlers[i-1](); |
| 1114 | } |
| 1115 | |
| 1116 | static void git_atexit_clear(void) |
| 1117 | { |
| 1118 | free(git_atexit_hdlrs.handlers); |
| 1119 | memset(&git_atexit_hdlrs, 0, sizeof(git_atexit_hdlrs)); |
| 1120 | git_atexit_installed = 0; |
| 1121 | } |
| 1122 | |
| 1123 | #undef atexit |
| 1124 | int git_atexit(void (*handler)(void)) |
| 1125 | { |
| 1126 | ALLOC_GROW(git_atexit_hdlrs.handlers, git_atexit_hdlrs.nr + 1, git_atexit_hdlrs.alloc); |
| 1127 | git_atexit_hdlrs.handlers[git_atexit_hdlrs.nr++] = handler; |
| 1128 | if (!git_atexit_installed) { |
| 1129 | if (atexit(&git_atexit_dispatch)) |
| 1130 | return -1; |
| 1131 | git_atexit_installed = 1; |
| 1132 | } |
| 1133 | return 0; |
| 1134 | } |
| 1135 | #define atexit git_atexit |
| 1136 | |
| 1137 | static int process_is_async; |
| 1138 | int in_async(void) |
| 1139 | { |
| 1140 | return process_is_async; |
| 1141 | } |
| 1142 | |
| 1143 | static void NORETURN async_exit(int code) |
| 1144 | { |
| 1145 | exit(code); |
| 1146 | } |
| 1147 | |
| 1148 | #endif |
| 1149 | |
| 1150 | void check_pipe(int err) |
| 1151 | { |
| 1152 | if (err == EPIPE) { |
| 1153 | if (in_async()) |
| 1154 | async_exit(141); |
| 1155 | |
| 1156 | signal(SIGPIPE, SIG_DFL); |
| 1157 | raise(SIGPIPE); |
| 1158 | /* Should never happen, but just in case... */ |
| 1159 | exit(141); |
| 1160 | } |
| 1161 | } |
| 1162 | |
| 1163 | int start_async(struct async *async) |
| 1164 | { |
| 1165 | int need_in, need_out; |
| 1166 | int fdin[2], fdout[2]; |
| 1167 | int proc_in, proc_out; |
| 1168 | |
| 1169 | need_in = async->in < 0; |
| 1170 | if (need_in) { |
| 1171 | if (pipe(fdin) < 0) { |
| 1172 | if (async->out > 0) |
| 1173 | close(async->out); |
| 1174 | return error_errno("cannot create pipe"); |
| 1175 | } |
| 1176 | async->in = fdin[1]; |
| 1177 | } |
| 1178 | |
| 1179 | need_out = async->out < 0; |
| 1180 | if (need_out) { |
| 1181 | if (pipe(fdout) < 0) { |
| 1182 | if (need_in) |
| 1183 | close_pair(fdin); |
| 1184 | else if (async->in) |
| 1185 | close(async->in); |
| 1186 | return error_errno("cannot create pipe"); |
| 1187 | } |
| 1188 | async->out = fdout[0]; |
| 1189 | } |
| 1190 | |
| 1191 | if (need_in) |
| 1192 | proc_in = fdin[0]; |
| 1193 | else if (async->in) |
| 1194 | proc_in = async->in; |
| 1195 | else |
| 1196 | proc_in = -1; |
| 1197 | |
| 1198 | if (need_out) |
| 1199 | proc_out = fdout[1]; |
| 1200 | else if (async->out) |
| 1201 | proc_out = async->out; |
| 1202 | else |
| 1203 | proc_out = -1; |
| 1204 | |
| 1205 | #ifdef NO_PTHREADS |
| 1206 | /* Flush stdio before fork() to avoid cloning buffers */ |
| 1207 | fflush(NULL); |
| 1208 | |
| 1209 | async->pid = fork(); |
| 1210 | if (async->pid < 0) { |
| 1211 | error_errno("fork (async) failed"); |
| 1212 | goto error; |
| 1213 | } |
| 1214 | if (!async->pid) { |
| 1215 | if (need_in) |
| 1216 | close(fdin[1]); |
| 1217 | if (need_out) |
| 1218 | close(fdout[0]); |
| 1219 | git_atexit_clear(); |
| 1220 | process_is_async = 1; |
| 1221 | exit(!!async->proc(proc_in, proc_out, async->data)); |
| 1222 | } |
| 1223 | |
| 1224 | mark_child_for_cleanup(async->pid, NULL); |
| 1225 | |
| 1226 | if (need_in) |
| 1227 | close(fdin[0]); |
| 1228 | else if (async->in) |
| 1229 | close(async->in); |
| 1230 | |
| 1231 | if (need_out) |
| 1232 | close(fdout[1]); |
| 1233 | else if (async->out) |
| 1234 | close(async->out); |
| 1235 | #else |
| 1236 | if (!main_thread_set) { |
| 1237 | /* |
| 1238 | * We assume that the first time that start_async is called |
| 1239 | * it is from the main thread. |
| 1240 | */ |
| 1241 | main_thread_set = 1; |
| 1242 | main_thread = pthread_self(); |
| 1243 | pthread_key_create(&async_key, NULL); |
| 1244 | pthread_key_create(&async_die_counter, NULL); |
| 1245 | set_die_routine(die_async); |
| 1246 | set_die_is_recursing_routine(async_die_is_recursing); |
| 1247 | } |
| 1248 | |
| 1249 | if (proc_in >= 0) |
| 1250 | set_cloexec(proc_in); |
| 1251 | if (proc_out >= 0) |
| 1252 | set_cloexec(proc_out); |
| 1253 | async->proc_in = proc_in; |
| 1254 | async->proc_out = proc_out; |
| 1255 | { |
| 1256 | int err = pthread_create(&async->tid, NULL, run_thread, async); |
| 1257 | if (err) { |
| 1258 | error(_("cannot create async thread: %s"), strerror(err)); |
| 1259 | goto error; |
| 1260 | } |
| 1261 | } |
| 1262 | #endif |
| 1263 | return 0; |
| 1264 | |
| 1265 | error: |
| 1266 | if (need_in) |
| 1267 | close_pair(fdin); |
| 1268 | else if (async->in) |
| 1269 | close(async->in); |
| 1270 | |
| 1271 | if (need_out) |
| 1272 | close_pair(fdout); |
| 1273 | else if (async->out) |
| 1274 | close(async->out); |
| 1275 | return -1; |
| 1276 | } |
| 1277 | |
| 1278 | int finish_async(struct async *async) |
| 1279 | { |
| 1280 | #ifdef NO_PTHREADS |
| 1281 | int ret = wait_or_whine(async->pid, "child process", 0); |
| 1282 | |
| 1283 | invalidate_lstat_cache(); |
| 1284 | |
| 1285 | return ret; |
| 1286 | #else |
| 1287 | void *ret = (void *)(intptr_t)(-1); |
| 1288 | |
| 1289 | if (pthread_join(async->tid, &ret)) |
| 1290 | error("pthread_join failed"); |
| 1291 | invalidate_lstat_cache(); |
| 1292 | return (int)(intptr_t)ret; |
| 1293 | |
| 1294 | #endif |
| 1295 | } |
| 1296 | |
| 1297 | int async_with_fork(void) |
| 1298 | { |
| 1299 | #ifdef NO_PTHREADS |
| 1300 | return 1; |
| 1301 | #else |
| 1302 | return 0; |
| 1303 | #endif |
| 1304 | } |
| 1305 | |
| 1306 | struct io_pump { |
| 1307 | /* initialized by caller */ |
| 1308 | int fd; |
| 1309 | int type; /* POLLOUT or POLLIN */ |
| 1310 | union { |
| 1311 | struct { |
| 1312 | const char *buf; |
| 1313 | size_t len; |
| 1314 | } out; |
| 1315 | struct { |
| 1316 | struct strbuf *buf; |
| 1317 | size_t hint; |
| 1318 | } in; |
| 1319 | } u; |
| 1320 | |
| 1321 | /* returned by pump_io */ |
| 1322 | int error; /* 0 for success, otherwise errno */ |
| 1323 | |
| 1324 | /* internal use */ |
| 1325 | struct pollfd *pfd; |
| 1326 | }; |
| 1327 | |
| 1328 | static int pump_io_round(struct io_pump *slots, int nr, struct pollfd *pfd) |
| 1329 | { |
| 1330 | int pollsize = 0; |
| 1331 | int i; |
| 1332 | |
| 1333 | for (i = 0; i < nr; i++) { |
| 1334 | struct io_pump *io = &slots[i]; |
| 1335 | if (io->fd < 0) |
| 1336 | continue; |
| 1337 | pfd[pollsize].fd = io->fd; |
| 1338 | pfd[pollsize].events = io->type; |
| 1339 | io->pfd = &pfd[pollsize++]; |
| 1340 | } |
| 1341 | |
| 1342 | if (!pollsize) |
| 1343 | return 0; |
| 1344 | |
| 1345 | if (poll(pfd, pollsize, -1) < 0) { |
| 1346 | if (errno == EINTR) |
| 1347 | return 1; |
| 1348 | die_errno("poll failed"); |
| 1349 | } |
| 1350 | |
| 1351 | for (i = 0; i < nr; i++) { |
| 1352 | struct io_pump *io = &slots[i]; |
| 1353 | |
| 1354 | if (io->fd < 0) |
| 1355 | continue; |
| 1356 | |
| 1357 | if (!(io->pfd->revents & (POLLOUT|POLLIN|POLLHUP|POLLERR|POLLNVAL))) |
| 1358 | continue; |
| 1359 | |
| 1360 | if (io->type == POLLOUT) { |
| 1361 | ssize_t len; |
| 1362 | |
| 1363 | /* |
| 1364 | * Don't use xwrite() here. It loops forever on EAGAIN, |
| 1365 | * and we're in our own poll() loop here. |
| 1366 | * |
| 1367 | * Note that we lose xwrite()'s handling of MAX_IO_SIZE |
| 1368 | * and EINTR, so we have to implement those ourselves. |
| 1369 | */ |
| 1370 | len = write(io->fd, io->u.out.buf, |
| 1371 | io->u.out.len <= MAX_IO_SIZE ? |
| 1372 | io->u.out.len : MAX_IO_SIZE); |
| 1373 | if (len < 0) { |
| 1374 | if (errno != EINTR && errno != EAGAIN && |
| 1375 | errno != ENOSPC) { |
| 1376 | io->error = errno; |
| 1377 | close(io->fd); |
| 1378 | io->fd = -1; |
| 1379 | } |
| 1380 | } else { |
| 1381 | io->u.out.buf += len; |
| 1382 | io->u.out.len -= len; |
| 1383 | if (!io->u.out.len) { |
| 1384 | close(io->fd); |
| 1385 | io->fd = -1; |
| 1386 | } |
| 1387 | } |
| 1388 | } |
| 1389 | |
| 1390 | if (io->type == POLLIN) { |
| 1391 | ssize_t len = strbuf_read_once(io->u.in.buf, |
| 1392 | io->fd, io->u.in.hint); |
| 1393 | if (len < 0) |
| 1394 | io->error = errno; |
| 1395 | if (len <= 0) { |
| 1396 | close(io->fd); |
| 1397 | io->fd = -1; |
| 1398 | } |
| 1399 | } |
| 1400 | } |
| 1401 | |
| 1402 | return 1; |
| 1403 | } |
| 1404 | |
| 1405 | static int pump_io(struct io_pump *slots, int nr) |
| 1406 | { |
| 1407 | struct pollfd *pfd; |
| 1408 | int i; |
| 1409 | |
| 1410 | for (i = 0; i < nr; i++) |
| 1411 | slots[i].error = 0; |
| 1412 | |
| 1413 | ALLOC_ARRAY(pfd, nr); |
| 1414 | while (pump_io_round(slots, nr, pfd)) |
| 1415 | ; /* nothing */ |
| 1416 | free(pfd); |
| 1417 | |
| 1418 | /* There may be multiple errno values, so just pick the first. */ |
| 1419 | for (i = 0; i < nr; i++) { |
| 1420 | if (slots[i].error) { |
| 1421 | errno = slots[i].error; |
| 1422 | return -1; |
| 1423 | } |
| 1424 | } |
| 1425 | return 0; |
| 1426 | } |
| 1427 | |
| 1428 | |
| 1429 | int pipe_command(struct child_process *cmd, |
| 1430 | const char *in, size_t in_len, |
| 1431 | struct strbuf *out, size_t out_hint, |
| 1432 | struct strbuf *err, size_t err_hint) |
| 1433 | { |
| 1434 | struct io_pump io[3]; |
| 1435 | int nr = 0; |
| 1436 | |
| 1437 | if (in) |
| 1438 | cmd->in = -1; |
| 1439 | if (out) |
| 1440 | cmd->out = -1; |
| 1441 | if (err) |
| 1442 | cmd->err = -1; |
| 1443 | |
| 1444 | if (start_command(cmd) < 0) |
| 1445 | return -1; |
| 1446 | |
| 1447 | if (in) { |
| 1448 | if (enable_pipe_nonblock(cmd->in) < 0) { |
| 1449 | error_errno("unable to make pipe non-blocking"); |
| 1450 | close(cmd->in); |
| 1451 | if (out) |
| 1452 | close(cmd->out); |
| 1453 | if (err) |
| 1454 | close(cmd->err); |
| 1455 | return -1; |
| 1456 | } |
| 1457 | io[nr].fd = cmd->in; |
| 1458 | io[nr].type = POLLOUT; |
| 1459 | io[nr].u.out.buf = in; |
| 1460 | io[nr].u.out.len = in_len; |
| 1461 | nr++; |
| 1462 | } |
| 1463 | if (out) { |
| 1464 | io[nr].fd = cmd->out; |
| 1465 | io[nr].type = POLLIN; |
| 1466 | io[nr].u.in.buf = out; |
| 1467 | io[nr].u.in.hint = out_hint; |
| 1468 | nr++; |
| 1469 | } |
| 1470 | if (err) { |
| 1471 | io[nr].fd = cmd->err; |
| 1472 | io[nr].type = POLLIN; |
| 1473 | io[nr].u.in.buf = err; |
| 1474 | io[nr].u.in.hint = err_hint; |
| 1475 | nr++; |
| 1476 | } |
| 1477 | |
| 1478 | if (pump_io(io, nr) < 0) { |
| 1479 | finish_command(cmd); /* throw away exit code */ |
| 1480 | return -1; |
| 1481 | } |
| 1482 | |
| 1483 | return finish_command(cmd); |
| 1484 | } |
| 1485 | |
| 1486 | enum child_state { |
| 1487 | GIT_CP_FREE, |
| 1488 | GIT_CP_WORKING, |
| 1489 | GIT_CP_WAIT_CLEANUP, |
| 1490 | }; |
| 1491 | |
| 1492 | struct parallel_child { |
| 1493 | enum child_state state; |
| 1494 | struct child_process process; |
| 1495 | struct strbuf err; |
| 1496 | void *data; |
| 1497 | }; |
| 1498 | |
| 1499 | static int child_is_working(const struct parallel_child *pp_child) |
| 1500 | { |
| 1501 | return pp_child->state == GIT_CP_WORKING; |
| 1502 | } |
| 1503 | |
| 1504 | static int child_is_ready_for_cleanup(const struct parallel_child *pp_child) |
| 1505 | { |
| 1506 | return child_is_working(pp_child) && !pp_child->process.in; |
| 1507 | } |
| 1508 | |
| 1509 | static int child_is_receiving_input(const struct parallel_child *pp_child) |
| 1510 | { |
| 1511 | return child_is_working(pp_child) && pp_child->process.in > 0; |
| 1512 | } |
| 1513 | static int child_is_sending_output(const struct parallel_child *pp_child) |
| 1514 | { |
| 1515 | /* |
| 1516 | * all pp children which buffer output through run_command via ungroup=0 |
| 1517 | * redirect stdout to stderr, so we just need to check process.err. |
| 1518 | */ |
| 1519 | return child_is_working(pp_child) && pp_child->process.err > 0; |
| 1520 | } |
| 1521 | |
| 1522 | struct parallel_processes { |
| 1523 | size_t nr_processes; |
| 1524 | |
| 1525 | struct parallel_child *children; |
| 1526 | /* |
| 1527 | * The struct pollfd is logically part of *children, |
| 1528 | * but the system call expects it as its own array. |
| 1529 | */ |
| 1530 | struct pollfd *pfd; |
| 1531 | |
| 1532 | unsigned shutdown : 1; |
| 1533 | |
| 1534 | size_t output_owner; |
| 1535 | struct strbuf buffered_output; /* of finished children */ |
| 1536 | }; |
| 1537 | |
| 1538 | struct parallel_processes_for_signal { |
| 1539 | const struct run_process_parallel_opts *opts; |
| 1540 | const struct parallel_processes *pp; |
| 1541 | }; |
| 1542 | |
| 1543 | static void kill_children(const struct parallel_processes *pp, |
| 1544 | const struct run_process_parallel_opts *opts, |
| 1545 | int signo) |
| 1546 | { |
| 1547 | for (size_t i = 0; i < opts->processes; i++) |
| 1548 | if (child_is_working(&pp->children[i])) |
| 1549 | kill(pp->children[i].process.pid, signo); |
| 1550 | } |
| 1551 | |
| 1552 | static void kill_children_signal(const struct parallel_processes_for_signal *pp_sig, |
| 1553 | int signo) |
| 1554 | { |
| 1555 | kill_children(pp_sig->pp, pp_sig->opts, signo); |
| 1556 | } |
| 1557 | |
| 1558 | static struct parallel_processes_for_signal *pp_for_signal; |
| 1559 | |
| 1560 | static void handle_children_on_signal(int signo) |
| 1561 | { |
| 1562 | kill_children_signal(pp_for_signal, signo); |
| 1563 | sigchain_pop(signo); |
| 1564 | raise(signo); |
| 1565 | } |
| 1566 | |
| 1567 | static void pp_init(struct parallel_processes *pp, |
| 1568 | const struct run_process_parallel_opts *opts, |
| 1569 | struct parallel_processes_for_signal *pp_sig) |
| 1570 | { |
| 1571 | const size_t n = opts->processes; |
| 1572 | |
| 1573 | if (!n) |
| 1574 | BUG("you must provide a non-zero number of processes!"); |
| 1575 | |
| 1576 | trace_printf("run_processes_parallel: preparing to run up to %"PRIuMAX" tasks", |
| 1577 | (uintmax_t)n); |
| 1578 | |
| 1579 | if (!opts->get_next_task) |
| 1580 | BUG("you need to specify a get_next_task function"); |
| 1581 | |
| 1582 | CALLOC_ARRAY(pp->children, n); |
| 1583 | if (!opts->ungroup) |
| 1584 | CALLOC_ARRAY(pp->pfd, n * 2); |
| 1585 | |
| 1586 | for (size_t i = 0; i < n; i++) { |
| 1587 | strbuf_init(&pp->children[i].err, 0); |
| 1588 | child_process_init(&pp->children[i].process); |
| 1589 | if (pp->pfd) { |
| 1590 | pp->pfd[i].events = POLLIN | POLLHUP; |
| 1591 | pp->pfd[i].fd = -1; |
| 1592 | } |
| 1593 | } |
| 1594 | |
| 1595 | pp_sig->pp = pp; |
| 1596 | pp_sig->opts = opts; |
| 1597 | pp_for_signal = pp_sig; |
| 1598 | sigchain_push_common(handle_children_on_signal); |
| 1599 | } |
| 1600 | |
| 1601 | static void pp_cleanup(struct parallel_processes *pp, |
| 1602 | const struct run_process_parallel_opts *opts) |
| 1603 | { |
| 1604 | trace_printf("run_processes_parallel: done"); |
| 1605 | for (size_t i = 0; i < opts->processes; i++) { |
| 1606 | strbuf_release(&pp->children[i].err); |
| 1607 | child_process_clear(&pp->children[i].process); |
| 1608 | } |
| 1609 | |
| 1610 | free(pp->children); |
| 1611 | free(pp->pfd); |
| 1612 | |
| 1613 | /* |
| 1614 | * When get_next_task added messages to the buffer in its last |
| 1615 | * iteration, the buffered output is non empty. |
| 1616 | */ |
| 1617 | strbuf_write(&pp->buffered_output, stderr); |
| 1618 | strbuf_release(&pp->buffered_output); |
| 1619 | |
| 1620 | sigchain_pop_common(); |
| 1621 | } |
| 1622 | |
| 1623 | /* returns |
| 1624 | * 0 if a new task was started. |
| 1625 | * 1 if no new jobs was started (get_next_task ran out of work, non critical |
| 1626 | * problem with starting a new command) |
| 1627 | * <0 no new job was started, user wishes to shutdown early. Use negative code |
| 1628 | * to signal the children. |
| 1629 | */ |
| 1630 | static int pp_start_one(struct parallel_processes *pp, |
| 1631 | const struct run_process_parallel_opts *opts) |
| 1632 | { |
| 1633 | size_t i; |
| 1634 | int code; |
| 1635 | |
| 1636 | for (i = 0; i < opts->processes; i++) |
| 1637 | if (pp->children[i].state == GIT_CP_FREE) |
| 1638 | break; |
| 1639 | if (i == opts->processes) |
| 1640 | BUG("bookkeeping is hard"); |
| 1641 | |
| 1642 | /* |
| 1643 | * By default, do not inherit stdin from the parent process - otherwise, |
| 1644 | * all children would share stdin! Users may overwrite this to provide |
| 1645 | * something to the child's stdin by having their 'get_next_task' |
| 1646 | * callback assign 0 to .no_stdin and an appropriate integer to .in. |
| 1647 | */ |
| 1648 | pp->children[i].process.no_stdin = 1; |
| 1649 | |
| 1650 | code = opts->get_next_task(&pp->children[i].process, |
| 1651 | opts->ungroup ? NULL : &pp->children[i].err, |
| 1652 | opts->data, |
| 1653 | &pp->children[i].data); |
| 1654 | if (!code) { |
| 1655 | if (!opts->ungroup) { |
| 1656 | strbuf_addbuf(&pp->buffered_output, &pp->children[i].err); |
| 1657 | strbuf_reset(&pp->children[i].err); |
| 1658 | } |
| 1659 | return 1; |
| 1660 | } |
| 1661 | if (!opts->ungroup) { |
| 1662 | pp->children[i].process.err = -1; |
| 1663 | pp->children[i].process.stdout_to_stderr = 1; |
| 1664 | } |
| 1665 | |
| 1666 | if (start_command(&pp->children[i].process)) { |
| 1667 | if (opts->start_failure) |
| 1668 | code = opts->start_failure(opts->ungroup ? NULL : |
| 1669 | &pp->children[i].err, |
| 1670 | opts->data, |
| 1671 | pp->children[i].data); |
| 1672 | else |
| 1673 | code = 0; |
| 1674 | |
| 1675 | if (!opts->ungroup) { |
| 1676 | strbuf_addbuf(&pp->buffered_output, &pp->children[i].err); |
| 1677 | strbuf_reset(&pp->children[i].err); |
| 1678 | } |
| 1679 | if (code) |
| 1680 | pp->shutdown = 1; |
| 1681 | return code; |
| 1682 | } |
| 1683 | |
| 1684 | pp->nr_processes++; |
| 1685 | pp->children[i].state = GIT_CP_WORKING; |
| 1686 | if (pp->pfd) |
| 1687 | pp->pfd[i].fd = pp->children[i].process.err; |
| 1688 | return 0; |
| 1689 | } |
| 1690 | |
| 1691 | static void pp_buffer_stdin(struct parallel_processes *pp, |
| 1692 | const struct run_process_parallel_opts *opts) |
| 1693 | { |
| 1694 | /* Buffer stdin for each pipe. */ |
| 1695 | for (size_t i = 0; i < opts->processes; i++) { |
| 1696 | struct child_process *proc = &pp->children[i].process; |
| 1697 | int ret; |
| 1698 | |
| 1699 | if (!child_is_receiving_input(&pp->children[i])) |
| 1700 | continue; |
| 1701 | |
| 1702 | /* |
| 1703 | * child input is provided via path_to_stdin when the feed_pipe cb is |
| 1704 | * missing, so we just signal an EOF. |
| 1705 | */ |
| 1706 | if (!opts->feed_pipe) { |
| 1707 | close(proc->in); |
| 1708 | proc->in = 0; |
| 1709 | continue; |
| 1710 | } |
| 1711 | |
| 1712 | /** |
| 1713 | * Feed the pipe: |
| 1714 | * ret < 0 means error |
| 1715 | * ret == 0 means there is more data to be fed |
| 1716 | * ret > 0 means feeding finished |
| 1717 | */ |
| 1718 | ret = opts->feed_pipe(proc->in, opts->data, pp->children[i].data); |
| 1719 | if (ret < 0) |
| 1720 | die_errno("feed_pipe"); |
| 1721 | |
| 1722 | if (ret) { |
| 1723 | close(proc->in); |
| 1724 | proc->in = 0; |
| 1725 | } |
| 1726 | } |
| 1727 | } |
| 1728 | |
| 1729 | static void pp_buffer_io(struct parallel_processes *pp, |
| 1730 | const struct run_process_parallel_opts *opts, |
| 1731 | int timeout) |
| 1732 | { |
| 1733 | /* for each potential child slot, prepare two pollfd entries */ |
| 1734 | for (size_t i = 0; i < opts->processes; i++) { |
| 1735 | if (child_is_sending_output(&pp->children[i])) { |
| 1736 | pp->pfd[2*i].fd = pp->children[i].process.err; |
| 1737 | pp->pfd[2*i].events = POLLIN | POLLHUP; |
| 1738 | } else { |
| 1739 | pp->pfd[2*i].fd = -1; |
| 1740 | } |
| 1741 | |
| 1742 | if (child_is_receiving_input(&pp->children[i])) { |
| 1743 | pp->pfd[2*i+1].fd = pp->children[i].process.in; |
| 1744 | pp->pfd[2*i+1].events = POLLOUT; |
| 1745 | } else { |
| 1746 | pp->pfd[2*i+1].fd = -1; |
| 1747 | } |
| 1748 | } |
| 1749 | |
| 1750 | while (poll(pp->pfd, opts->processes * 2, timeout) < 0) { |
| 1751 | if (errno == EINTR) |
| 1752 | continue; |
| 1753 | pp_cleanup(pp, opts); |
| 1754 | die_errno("poll"); |
| 1755 | } |
| 1756 | |
| 1757 | for (size_t i = 0; i < opts->processes; i++) { |
| 1758 | /* Handle input feeding (stdin) */ |
| 1759 | if (pp->pfd[2*i+1].revents & (POLLOUT | POLLHUP | POLLERR)) { |
| 1760 | if (opts->feed_pipe) { |
| 1761 | int ret = opts->feed_pipe(pp->children[i].process.in, |
| 1762 | opts->data, |
| 1763 | pp->children[i].data); |
| 1764 | if (ret < 0) |
| 1765 | die_errno("feed_pipe"); |
| 1766 | if (ret) { |
| 1767 | /* done feeding */ |
| 1768 | close(pp->children[i].process.in); |
| 1769 | pp->children[i].process.in = 0; |
| 1770 | } |
| 1771 | } else { |
| 1772 | /* |
| 1773 | * No feed_pipe means there is nothing to do, so |
| 1774 | * close the fd. Child input can be fed by other |
| 1775 | * methods, such as opts->path_to_stdin which |
| 1776 | * slurps a file via dup2, so clean up here. |
| 1777 | */ |
| 1778 | close(pp->children[i].process.in); |
| 1779 | pp->children[i].process.in = 0; |
| 1780 | } |
| 1781 | } |
| 1782 | |
| 1783 | /* Handle output reading (stderr) */ |
| 1784 | if (child_is_working(&pp->children[i]) && |
| 1785 | pp->pfd[2*i].revents & (POLLIN | POLLHUP)) { |
| 1786 | int n = strbuf_read_once(&pp->children[i].err, |
| 1787 | pp->children[i].process.err, 0); |
| 1788 | if (n == 0) { |
| 1789 | close(pp->children[i].process.err); |
| 1790 | pp->children[i].state = GIT_CP_WAIT_CLEANUP; |
| 1791 | } else if (n < 0) |
| 1792 | if (errno != EAGAIN) |
| 1793 | die_errno("read"); |
| 1794 | } |
| 1795 | } |
| 1796 | } |
| 1797 | |
| 1798 | static void pp_output(const struct parallel_processes *pp) |
| 1799 | { |
| 1800 | size_t i = pp->output_owner; |
| 1801 | |
| 1802 | if (child_is_working(&pp->children[i]) && |
| 1803 | pp->children[i].err.len) { |
| 1804 | strbuf_write(&pp->children[i].err, stderr); |
| 1805 | strbuf_reset(&pp->children[i].err); |
| 1806 | } |
| 1807 | } |
| 1808 | |
| 1809 | static int pp_collect_finished(struct parallel_processes *pp, |
| 1810 | const struct run_process_parallel_opts *opts) |
| 1811 | { |
| 1812 | int code; |
| 1813 | size_t i; |
| 1814 | int result = 0; |
| 1815 | |
| 1816 | while (pp->nr_processes > 0) { |
| 1817 | for (i = 0; i < opts->processes; i++) |
| 1818 | if (pp->children[i].state == GIT_CP_WAIT_CLEANUP) |
| 1819 | break; |
| 1820 | if (i == opts->processes) |
| 1821 | break; |
| 1822 | |
| 1823 | code = finish_command(&pp->children[i].process); |
| 1824 | |
| 1825 | if (opts->task_finished) |
| 1826 | code = opts->task_finished(code, opts->ungroup ? NULL : |
| 1827 | &pp->children[i].err, opts->data, |
| 1828 | pp->children[i].data); |
| 1829 | else |
| 1830 | code = 0; |
| 1831 | |
| 1832 | if (code) |
| 1833 | result = code; |
| 1834 | if (code < 0) |
| 1835 | break; |
| 1836 | |
| 1837 | pp->nr_processes--; |
| 1838 | pp->children[i].state = GIT_CP_FREE; |
| 1839 | if (pp->pfd) |
| 1840 | pp->pfd[i].fd = -1; |
| 1841 | pp->children[i].process.in = 0; |
| 1842 | child_process_init(&pp->children[i].process); |
| 1843 | |
| 1844 | if (opts->ungroup) { |
| 1845 | ; /* no strbuf_*() work to do here */ |
| 1846 | } else if (i != pp->output_owner) { |
| 1847 | strbuf_addbuf(&pp->buffered_output, &pp->children[i].err); |
| 1848 | strbuf_reset(&pp->children[i].err); |
| 1849 | } else { |
| 1850 | const size_t n = opts->processes; |
| 1851 | |
| 1852 | strbuf_write(&pp->children[i].err, stderr); |
| 1853 | strbuf_reset(&pp->children[i].err); |
| 1854 | |
| 1855 | /* Output all other finished child processes */ |
| 1856 | strbuf_write(&pp->buffered_output, stderr); |
| 1857 | strbuf_reset(&pp->buffered_output); |
| 1858 | |
| 1859 | /* |
| 1860 | * Pick next process to output live. |
| 1861 | * NEEDSWORK: |
| 1862 | * For now we pick it randomly by doing a round |
| 1863 | * robin. Later we may want to pick the one with |
| 1864 | * the most output or the longest or shortest |
| 1865 | * running process time. |
| 1866 | */ |
| 1867 | for (i = 0; i < n; i++) |
| 1868 | if (child_is_working(&pp->children[(pp->output_owner + i) % n])) |
| 1869 | break; |
| 1870 | pp->output_owner = (pp->output_owner + i) % n; |
| 1871 | } |
| 1872 | } |
| 1873 | return result; |
| 1874 | } |
| 1875 | |
| 1876 | static void pp_handle_child_IO(struct parallel_processes *pp, |
| 1877 | const struct run_process_parallel_opts *opts, |
| 1878 | int timeout) |
| 1879 | { |
| 1880 | if (opts->ungroup) { |
| 1881 | pp_buffer_stdin(pp, opts); |
| 1882 | for (size_t i = 0; i < opts->processes; i++) |
| 1883 | if (child_is_ready_for_cleanup(&pp->children[i])) |
| 1884 | pp->children[i].state = GIT_CP_WAIT_CLEANUP; |
| 1885 | } else { |
| 1886 | pp_buffer_io(pp, opts, timeout); |
| 1887 | pp_output(pp); |
| 1888 | } |
| 1889 | } |
| 1890 | |
| 1891 | void run_processes_parallel(const struct run_process_parallel_opts *opts) |
| 1892 | { |
| 1893 | int i, code; |
| 1894 | int timeout = 100; |
| 1895 | int spawn_cap = 4; |
| 1896 | struct parallel_processes_for_signal pp_sig; |
| 1897 | struct parallel_processes pp = { |
| 1898 | .buffered_output = STRBUF_INIT, |
| 1899 | }; |
| 1900 | /* options */ |
| 1901 | const char *tr2_category = opts->tr2_category; |
| 1902 | const char *tr2_label = opts->tr2_label; |
| 1903 | const int do_trace2 = tr2_category && tr2_label; |
| 1904 | |
| 1905 | if (do_trace2) |
| 1906 | trace2_region_enter_printf(tr2_category, tr2_label, NULL, |
| 1907 | "max:%"PRIuMAX, |
| 1908 | (uintmax_t)opts->processes); |
| 1909 | |
| 1910 | pp_init(&pp, opts, &pp_sig); |
| 1911 | |
| 1912 | /* |
| 1913 | * Child tasks might receive input via stdin, terminating early (or not), so |
| 1914 | * ignore the default SIGPIPE which gets handled by each feed_pipe_fn which |
| 1915 | * actually writes the data to children stdin fds. |
| 1916 | * |
| 1917 | * This _must_ come after pp_init(), because it installs its own |
| 1918 | * SIGPIPE handler (to cleanup children), and we want to supersede |
| 1919 | * that. |
| 1920 | */ |
| 1921 | sigchain_push(SIGPIPE, SIG_IGN); |
| 1922 | |
| 1923 | while (1) { |
| 1924 | for (i = 0; |
| 1925 | i < spawn_cap && !pp.shutdown && |
| 1926 | pp.nr_processes < opts->processes; |
| 1927 | i++) { |
| 1928 | code = pp_start_one(&pp, opts); |
| 1929 | if (!code) |
| 1930 | continue; |
| 1931 | if (code < 0) { |
| 1932 | pp.shutdown = 1; |
| 1933 | kill_children(&pp, opts, -code); |
| 1934 | } |
| 1935 | break; |
| 1936 | } |
| 1937 | if (!pp.nr_processes) |
| 1938 | break; |
| 1939 | pp_handle_child_IO(&pp, opts, timeout); |
| 1940 | code = pp_collect_finished(&pp, opts); |
| 1941 | if (code) { |
| 1942 | pp.shutdown = 1; |
| 1943 | if (code < 0) |
| 1944 | kill_children(&pp, opts,-code); |
| 1945 | } |
| 1946 | } |
| 1947 | |
| 1948 | sigchain_pop(SIGPIPE); |
| 1949 | |
| 1950 | pp_cleanup(&pp, opts); |
| 1951 | |
| 1952 | if (do_trace2) |
| 1953 | trace2_region_leave(tr2_category, tr2_label, NULL); |
| 1954 | } |
| 1955 | |
| 1956 | int prepare_auto_maintenance(struct repository *r, int quiet, |
| 1957 | struct child_process *maint) |
| 1958 | { |
| 1959 | int enabled = 1, auto_detach; |
| 1960 | |
| 1961 | if (repo_config_get_bool(r, "maintenance.auto", &enabled)) { |
| 1962 | int gc_threshold; |
| 1963 | if (!repo_config_get_int(r, "gc.auto", &gc_threshold)) |
| 1964 | enabled = gc_threshold > 0; |
| 1965 | } |
| 1966 | if (!enabled) |
| 1967 | return 0; |
| 1968 | |
| 1969 | /* |
| 1970 | * When `maintenance.autoDetach` isn't set, then we fall back to |
| 1971 | * honoring `gc.autoDetach`. This is somewhat weird, but required to |
| 1972 | * retain behaviour from when we used to run git-gc(1) here. |
| 1973 | */ |
| 1974 | if (repo_config_get_bool(r, "maintenance.autodetach", &auto_detach) && |
| 1975 | repo_config_get_bool(r, "gc.autodetach", &auto_detach)) |
| 1976 | auto_detach = git_env_bool("GIT_TEST_MAINT_AUTO_DETACH", true); |
| 1977 | |
| 1978 | maint->git_cmd = 1; |
| 1979 | maint->odb_to_close = r->objects; |
| 1980 | strvec_pushl(&maint->args, "maintenance", "run", "--auto", NULL); |
| 1981 | strvec_push(&maint->args, quiet ? "--quiet" : "--no-quiet"); |
| 1982 | strvec_push(&maint->args, auto_detach ? "--detach" : "--no-detach"); |
| 1983 | |
| 1984 | return 1; |
| 1985 | } |
| 1986 | |
| 1987 | int run_auto_maintenance(struct repository *r, int quiet) |
| 1988 | { |
| 1989 | struct child_process maint = CHILD_PROCESS_INIT; |
| 1990 | if (!prepare_auto_maintenance(r, quiet, &maint)) |
| 1991 | return 0; |
| 1992 | return run_command(&maint); |
| 1993 | } |
| 1994 | |
| 1995 | void sanitize_repo_env(struct strvec *env) |
| 1996 | { |
| 1997 | const char * const *var; |
| 1998 | |
| 1999 | for (var = local_repo_env; *var; var++) { |
| 2000 | if (strcmp(*var, CONFIG_DATA_ENVIRONMENT) && |
| 2001 | strcmp(*var, CONFIG_COUNT_ENVIRONMENT)) |
| 2002 | strvec_push(env, *var); |
| 2003 | } |
| 2004 | } |
| 2005 | |
| 2006 | void prepare_other_repo_env(struct strvec *env, const char *new_git_dir) |
| 2007 | { |
| 2008 | sanitize_repo_env(env); |
| 2009 | strvec_pushf(env, "%s=%s", GIT_DIR_ENVIRONMENT, new_git_dir); |
| 2010 | } |
| 2011 | |
| 2012 | enum start_bg_result start_bg_command(struct child_process *cmd, |
| 2013 | start_bg_wait_cb *wait_cb, |
| 2014 | void *cb_data, |
| 2015 | unsigned int timeout_sec) |
| 2016 | { |
| 2017 | enum start_bg_result sbgr = SBGR_ERROR; |
| 2018 | int ret; |
| 2019 | int wait_status; |
| 2020 | pid_t pid_seen; |
| 2021 | time_t time_limit; |
| 2022 | |
| 2023 | /* |
| 2024 | * We do not allow clean-on-exit because the child process |
| 2025 | * should persist in the background and possibly/probably |
| 2026 | * after this process exits. So we don't want to kill the |
| 2027 | * child during our atexit routine. |
| 2028 | */ |
| 2029 | if (cmd->clean_on_exit) |
| 2030 | BUG("start_bg_command() does not allow non-zero clean_on_exit"); |
| 2031 | |
| 2032 | if (!cmd->trace2_child_class) |
| 2033 | cmd->trace2_child_class = "background"; |
| 2034 | |
| 2035 | ret = start_command(cmd); |
| 2036 | if (ret) { |
| 2037 | /* |
| 2038 | * We assume that if `start_command()` fails, we |
| 2039 | * either get a complete `trace2_child_start() / |
| 2040 | * trace2_child_exit()` pair or it fails before the |
| 2041 | * `trace2_child_start()` is emitted, so we do not |
| 2042 | * need to worry about it here. |
| 2043 | * |
| 2044 | * We also assume that `start_command()` does not add |
| 2045 | * us to the cleanup list. And that it calls |
| 2046 | * `child_process_clear()`. |
| 2047 | */ |
| 2048 | sbgr = SBGR_ERROR; |
| 2049 | goto done; |
| 2050 | } |
| 2051 | |
| 2052 | time(&time_limit); |
| 2053 | time_limit += timeout_sec; |
| 2054 | |
| 2055 | wait: |
| 2056 | pid_seen = waitpid(cmd->pid, &wait_status, WNOHANG); |
| 2057 | |
| 2058 | if (!pid_seen) { |
| 2059 | /* |
| 2060 | * The child is currently running. Ask the callback |
| 2061 | * if the child is ready to do work or whether we |
| 2062 | * should keep waiting for it to boot up. |
| 2063 | */ |
| 2064 | ret = (*wait_cb)(cmd, cb_data); |
| 2065 | if (!ret) { |
| 2066 | /* |
| 2067 | * The child is running and "ready". |
| 2068 | */ |
| 2069 | trace2_child_ready(cmd, "ready"); |
| 2070 | sbgr = SBGR_READY; |
| 2071 | goto done; |
| 2072 | } else if (ret > 0) { |
| 2073 | /* |
| 2074 | * The callback said to give it more time to boot up |
| 2075 | * (subject to our timeout limit). |
| 2076 | */ |
| 2077 | time_t now; |
| 2078 | |
| 2079 | time(&now); |
| 2080 | if (now < time_limit) |
| 2081 | goto wait; |
| 2082 | |
| 2083 | /* |
| 2084 | * Our timeout has expired. We don't try to |
| 2085 | * kill the child, but rather let it continue |
| 2086 | * (hopefully) trying to startup. |
| 2087 | */ |
| 2088 | trace2_child_ready(cmd, "timeout"); |
| 2089 | sbgr = SBGR_TIMEOUT; |
| 2090 | goto done; |
| 2091 | } else { |
| 2092 | /* |
| 2093 | * The cb gave up on this child. It is still running, |
| 2094 | * but our cb got an error trying to probe it. |
| 2095 | */ |
| 2096 | trace2_child_ready(cmd, "error"); |
| 2097 | sbgr = SBGR_CB_ERROR; |
| 2098 | goto done; |
| 2099 | } |
| 2100 | } |
| 2101 | |
| 2102 | else if (pid_seen == cmd->pid) { |
| 2103 | int child_code = -1; |
| 2104 | |
| 2105 | /* |
| 2106 | * The child started, but exited or was terminated |
| 2107 | * before becoming "ready". |
| 2108 | * |
| 2109 | * We try to match the behavior of `wait_or_whine()` |
| 2110 | * WRT the handling of WIFSIGNALED() and WIFEXITED() |
| 2111 | * and convert the child's status to a return code for |
| 2112 | * tracing purposes and emit the `trace2_child_exit()` |
| 2113 | * event. |
| 2114 | * |
| 2115 | * We do not want the wait_or_whine() error message |
| 2116 | * because we will be called by client-side library |
| 2117 | * routines. |
| 2118 | */ |
| 2119 | if (WIFEXITED(wait_status)) |
| 2120 | child_code = WEXITSTATUS(wait_status); |
| 2121 | else if (WIFSIGNALED(wait_status)) |
| 2122 | child_code = WTERMSIG(wait_status) + 128; |
| 2123 | trace2_child_exit(cmd, child_code); |
| 2124 | |
| 2125 | sbgr = SBGR_DIED; |
| 2126 | goto done; |
| 2127 | } |
| 2128 | |
| 2129 | else if (pid_seen < 0 && errno == EINTR) |
| 2130 | goto wait; |
| 2131 | |
| 2132 | trace2_child_exit(cmd, -1); |
| 2133 | sbgr = SBGR_ERROR; |
| 2134 | |
| 2135 | done: |
| 2136 | child_process_clear(cmd); |
| 2137 | invalidate_lstat_cache(); |
| 2138 | return sbgr; |
| 2139 | } |