run-command.c

   1 #include "cache.h"
   2 #include "run-command.h"
   3 #include "exec_cmd.h"
   4 #include "sigchain.h"
   5 #include "argv-array.h"
   6
   7 #ifndef SHELL_PATH
   8 # define SHELL_PATH "/bin/sh"
   9 #endif
  10
  11 struct child_to_clean {
  12         pid_t pid;
  13         struct child_to_clean *next;
  14 };
  15 static struct child_to_clean *children_to_clean;
  16 static int installed_child_cleanup_handler;
  17
  18 static void cleanup_children(int sig)
  19 {
  20         while (children_to_clean) {
  21                 struct child_to_clean *p = children_to_clean;
  22                 children_to_clean = p->next;
  23                 kill(p->pid, sig);
  24                 free(p);
  25         }
  26 }
  27
  28 static void cleanup_children_on_signal(int sig)
  29 {
  30         cleanup_children(sig);
  31         sigchain_pop(sig);
  32         raise(sig);
  33 }
  34
  35 static void cleanup_children_on_exit(void)
  36 {
  37         cleanup_children(SIGTERM);
  38 }
  39
  40 static void mark_child_for_cleanup(pid_t pid)
  41 {
  42         struct child_to_clean *p = xmalloc(sizeof(*p));
  43         p->pid = pid;
  44         p->next = children_to_clean;
  45         children_to_clean = p;
  46
  47         if (!installed_child_cleanup_handler) {
  48                 atexit(cleanup_children_on_exit);
  49                 sigchain_push_common(cleanup_children_on_signal);
  50                 installed_child_cleanup_handler = 1;
  51         }
  52 }
  53
  54 static void clear_child_for_cleanup(pid_t pid)
  55 {
  56         struct child_to_clean **last, *p;
  57
  58         last = &children_to_clean;
  59         for (p = children_to_clean; p; p = p->next) {
  60                 if (p->pid == pid) {
  61                         *last = p->next;
  62                         free(p);
  63                         return;
  64                 }
  65         }
  66 }
  67
  68 static inline void close_pair(int fd[2])
  69 {
  70         close(fd[0]);
  71         close(fd[1]);
  72 }
  73
  74 #ifndef WIN32
  75 static inline void dup_devnull(int to)
  76 {
  77         int fd = open("/dev/null", O_RDWR);
  78         dup2(fd, to);
  79         close(fd);
  80 }
  81 #endif
  82
  83 static char *locate_in_PATH(const char *file)
  84 {
  85         const char *p = getenv("PATH");
  86         struct strbuf buf = STRBUF_INIT;
  87
  88         if (!p || !*p)
  89                 return NULL;
  90
  91         while (1) {
  92                 const char *end = strchrnul(p, ':');
  93
  94                 strbuf_reset(&buf);
  95
  96                 /* POSIX specifies an empty entry as the current directory. */
  97                 if (end != p) {
  98                         strbuf_add(&buf, p, end - p);
  99                         strbuf_addch(&buf, '/');
 100                 }
 101                 strbuf_addstr(&buf, file);
 102
 103                 if (!access(buf.buf, F_OK))
 104                         return strbuf_detach(&buf, NULL);
 105
 106                 if (!*end)
 107                         break;
 108                 p = end + 1;
 109         }
 110
 111         strbuf_release(&buf);
 112         return NULL;
 113 }
 114
 115 static int exists_in_PATH(const char *file)
 116 {
 117         char *r = locate_in_PATH(file);
 118         free(r);
 119         return r != NULL;
 120 }
 121
 122 int sane_execvp(const char *file, char * const argv[])
 123 {
 124         if (!execvp(file, argv))
 125                 return 0; /* cannot happen ;-) */
 126
 127         /*
 128          * When a command can't be found because one of the directories
 129          * listed in $PATH is unsearchable, execvp reports EACCES, but
 130          * careful usability testing (read: analysis of occasional bug
 131          * reports) reveals that "No such file or directory" is more
 132          * intuitive.
 133          *
 134          * We avoid commands with "/", because execvp will not do $PATH
 135          * lookups in that case.
 136          *
 137          * The reassignment of EACCES to errno looks like a no-op below,
 138          * but we need to protect against exists_in_PATH overwriting errno.
 139          */
 140         if (errno == EACCES && !strchr(file, '/'))
 141                 errno = exists_in_PATH(file) ? EACCES : ENOENT;
 142         else if (errno == ENOTDIR && !strchr(file, '/'))
 143                 errno = ENOENT;
 144         return -1;
 145 }
 146
 147 static const char **prepare_shell_cmd(const char **argv)
 148 {
 149         int argc, nargc = 0;
 150         const char **nargv;
 151
 152         for (argc = 0; argv[argc]; argc++)
 153                 ; /* just counting */
 154         /* +1 for NULL, +3 for "sh -c" plus extra $0 */
 155         nargv = xmalloc(sizeof(*nargv) * (argc + 1 + 3));
 156
 157         if (argc < 1)
 158                 die("BUG: shell command is empty");
 159
 160         if (strcspn(argv[0], "|&;<>()$`\\\"' \t\n*?[#~=%") != strlen(argv[0])) {
 161 #ifndef WIN32
 162                 nargv[nargc++] = SHELL_PATH;
 163 #else
 164                 nargv[nargc++] = "sh";
 165 #endif
 166                 nargv[nargc++] = "-c";
 167
 168                 if (argc < 2)
 169                         nargv[nargc++] = argv[0];
 170                 else {
 171                         struct strbuf arg0 = STRBUF_INIT;
 172                         strbuf_addf(&arg0, "%s \"$@\"", argv[0]);
 173                         nargv[nargc++] = strbuf_detach(&arg0, NULL);
 174                 }
 175         }
 176
 177         for (argc = 0; argv[argc]; argc++)
 178                 nargv[nargc++] = argv[argc];
 179         nargv[nargc] = NULL;
 180
 181         return nargv;
 182 }
 183
 184 #ifndef WIN32
 185 static int execv_shell_cmd(const char **argv)
 186 {
 187         const char **nargv = prepare_shell_cmd(argv);
 188         trace_argv_printf(nargv, "trace: exec:");
 189         sane_execvp(nargv[0], (char **)nargv);
 190         free(nargv);
 191         return -1;
 192 }
 193 #endif
 194
 195 #ifndef WIN32
 196 static int child_err = 2;
 197 static int child_notifier = -1;
 198
 199 static void notify_parent(void)
 200 {
 201         /*
 202          * execvp failed.  If possible, we'd like to let start_command
 203          * know, so failures like ENOENT can be handled right away; but
 204          * otherwise, finish_command will still report the error.
 205          */
 206         xwrite(child_notifier, "", 1);
 207 }
 208
 209 static NORETURN void die_child(const char *err, va_list params)
 210 {
 211         vwritef(child_err, "fatal: ", err, params);
 212         exit(128);
 213 }
 214
 215 static void error_child(const char *err, va_list params)
 216 {
 217         vwritef(child_err, "error: ", err, params);
 218 }
 219 #endif
 220
 221 static inline void set_cloexec(int fd)
 222 {
 223         int flags = fcntl(fd, F_GETFD);
 224         if (flags >= 0)
 225                 fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
 226 }
 227
 228 static int wait_or_whine(pid_t pid, const char *argv0, int silent_exec_failure)
 229 {
 230         int status, code = -1;
 231         pid_t waiting;
 232         int failed_errno = 0;
 233
 234         while ((waiting = waitpid(pid, &status, 0)) < 0 && errno == EINTR)
 235                 ;       /* nothing */
 236
 237         if (waiting < 0) {
 238                 failed_errno = errno;
 239                 error("waitpid for %s failed: %s", argv0, strerror(errno));
 240         } else if (waiting != pid) {
 241                 error("waitpid is confused (%s)", argv0);
 242         } else if (WIFSIGNALED(status)) {
 243                 code = WTERMSIG(status);
 244                 error("%s died of signal %d", argv0, code);
 245                 /*
 246                  * This return value is chosen so that code & 0xff
 247                  * mimics the exit code that a POSIX shell would report for
 248                  * a program that died from this signal.
 249                  */
 250                 code -= 128;
 251         } else if (WIFEXITED(status)) {
 252                 code = WEXITSTATUS(status);
 253                 /*
 254                  * Convert special exit code when execvp failed.
 255                  */
 256                 if (code == 127) {
 257                         code = -1;
 258                         failed_errno = ENOENT;
 259                 }
 260         } else {
 261                 error("waitpid is confused (%s)", argv0);
 262         }
 263
 264         clear_child_for_cleanup(pid);
 265
 266         errno = failed_errno;
 267         return code;
 268 }
 269
 270 int start_command(struct child_process *cmd)
 271 {
 272         int need_in, need_out, need_err;
 273         int fdin[2], fdout[2], fderr[2];
 274         int failed_errno = failed_errno;
 275
 276         /*
 277          * In case of errors we must keep the promise to close FDs
 278          * that have been passed in via ->in and ->out.
 279          */
 280
 281         need_in = !cmd->no_stdin && cmd->in < 0;
 282         if (need_in) {
 283                 if (pipe(fdin) < 0) {
 284                         failed_errno = errno;
 285                         if (cmd->out > 0)
 286                                 close(cmd->out);
 287                         goto fail_pipe;
 288                 }
 289                 cmd->in = fdin[1];
 290         }
 291
 292         need_out = !cmd->no_stdout
 293                 && !cmd->stdout_to_stderr
 294                 && cmd->out < 0;
 295         if (need_out) {
 296                 if (pipe(fdout) < 0) {
 297                         failed_errno = errno;
 298                         if (need_in)
 299                                 close_pair(fdin);
 300                         else if (cmd->in)
 301                                 close(cmd->in);
 302                         goto fail_pipe;
 303                 }
 304                 cmd->out = fdout[0];
 305         }
 306
 307         need_err = !cmd->no_stderr && cmd->err < 0;
 308         if (need_err) {
 309                 if (pipe(fderr) < 0) {
 310                         failed_errno = errno;
 311                         if (need_in)
 312                                 close_pair(fdin);
 313                         else if (cmd->in)
 314                                 close(cmd->in);
 315                         if (need_out)
 316                                 close_pair(fdout);
 317                         else if (cmd->out)
 318                                 close(cmd->out);
 319 fail_pipe:
 320                         error("cannot create pipe for %s: %s",
 321                                 cmd->argv[0], strerror(failed_errno));
 322                         errno = failed_errno;
 323                         return -1;
 324                 }
 325                 cmd->err = fderr[0];
 326         }
 327
 328         trace_argv_printf(cmd->argv, "trace: run_command:");
 329         fflush(NULL);
 330
 331 #ifndef WIN32
 332 {
 333         int notify_pipe[2];
 334         if (pipe(notify_pipe))
 335                 notify_pipe[0] = notify_pipe[1] = -1;
 336
 337         cmd->pid = fork();
 338         if (!cmd->pid) {
 339                 /*
 340                  * Redirect the channel to write syscall error messages to
 341                  * before redirecting the process's stderr so that all die()
 342                  * in subsequent call paths use the parent's stderr.
 343                  */
 344                 if (cmd->no_stderr || need_err) {
 345                         child_err = dup(2);
 346                         set_cloexec(child_err);
 347                 }
 348                 set_die_routine(die_child);
 349                 set_error_routine(error_child);
 350
 351                 close(notify_pipe[0]);
 352                 set_cloexec(notify_pipe[1]);
 353                 child_notifier = notify_pipe[1];
 354                 atexit(notify_parent);
 355
 356                 if (cmd->no_stdin)
 357                         dup_devnull(0);
 358                 else if (need_in) {
 359                         dup2(fdin[0], 0);
 360                         close_pair(fdin);
 361                 } else if (cmd->in) {
 362                         dup2(cmd->in, 0);
 363                         close(cmd->in);
 364                 }
 365
 366                 if (cmd->no_stderr)
 367                         dup_devnull(2);
 368                 else if (need_err) {
 369                         dup2(fderr[1], 2);
 370                         close_pair(fderr);
 371                 } else if (cmd->err > 1) {
 372                         dup2(cmd->err, 2);
 373                         close(cmd->err);
 374                 }
 375
 376                 if (cmd->no_stdout)
 377                         dup_devnull(1);
 378                 else if (cmd->stdout_to_stderr)
 379                         dup2(2, 1);
 380                 else if (need_out) {
 381                         dup2(fdout[1], 1);
 382                         close_pair(fdout);
 383                 } else if (cmd->out > 1) {
 384                         dup2(cmd->out, 1);
 385                         close(cmd->out);
 386                 }
 387
 388                 if (cmd->dir && chdir(cmd->dir))
 389                         die_errno("exec '%s': cd to '%s' failed", cmd->argv[0],
 390                             cmd->dir);
 391                 if (cmd->env) {
 392                         for (; *cmd->env; cmd->env++) {
 393                                 if (strchr(*cmd->env, '='))
 394                                         putenv((char *)*cmd->env);
 395                                 else
 396                                         unsetenv(*cmd->env);
 397                         }
 398                 }
 399                 if (cmd->preexec_cb) {
 400                         /*
 401                          * We cannot predict what the pre-exec callback does.
 402                          * Forgo parent notification.
 403                          */
 404                         close(child_notifier);
 405                         child_notifier = -1;
 406
 407                         cmd->preexec_cb();
 408                 }
 409                 if (cmd->git_cmd) {
 410                         execv_git_cmd(cmd->argv);
 411                 } else if (cmd->use_shell) {
 412                         execv_shell_cmd(cmd->argv);
 413                 } else {
 414                         sane_execvp(cmd->argv[0], (char *const*) cmd->argv);
 415                 }
 416                 if (errno == ENOENT) {
 417                         if (!cmd->silent_exec_failure)
 418                                 error("cannot run %s: %s", cmd->argv[0],
 419                                         strerror(ENOENT));
 420                         exit(127);
 421                 } else {
 422                         die_errno("cannot exec '%s'", cmd->argv[0]);
 423                 }
 424         }
 425         if (cmd->pid < 0)
 426                 error("cannot fork() for %s: %s", cmd->argv[0],
 427                         strerror(failed_errno = errno));
 428         else if (cmd->clean_on_exit)
 429                 mark_child_for_cleanup(cmd->pid);
 430
 431         /*
 432          * Wait for child's execvp. If the execvp succeeds (or if fork()
 433          * failed), EOF is seen immediately by the parent. Otherwise, the
 434          * child process sends a single byte.
 435          * Note that use of this infrastructure is completely advisory,
 436          * therefore, we keep error checks minimal.
 437          */
 438         close(notify_pipe[1]);
 439         if (read(notify_pipe[0], &notify_pipe[1], 1) == 1) {
 440                 /*
 441                  * At this point we know that fork() succeeded, but execvp()
 442                  * failed. Errors have been reported to our stderr.
 443                  */
 444                 wait_or_whine(cmd->pid, cmd->argv[0],
 445                               cmd->silent_exec_failure);
 446                 failed_errno = errno;
 447                 cmd->pid = -1;
 448         }
 449         close(notify_pipe[0]);
 450
 451 }
 452 #else
 453 {
 454         int fhin = 0, fhout = 1, fherr = 2;
 455         const char **sargv = cmd->argv;
 456         char **env = environ;
 457
 458         if (cmd->no_stdin)
 459                 fhin = open("/dev/null", O_RDWR);
 460         else if (need_in)
 461                 fhin = dup(fdin[0]);
 462         else if (cmd->in)
 463                 fhin = dup(cmd->in);
 464
 465         if (cmd->no_stderr)
 466                 fherr = open("/dev/null", O_RDWR);
 467         else if (need_err)
 468                 fherr = dup(fderr[1]);
 469         else if (cmd->err > 2)
 470                 fherr = dup(cmd->err);
 471
 472         if (cmd->no_stdout)
 473                 fhout = open("/dev/null", O_RDWR);
 474         else if (cmd->stdout_to_stderr)
 475                 fhout = dup(fherr);
 476         else if (need_out)
 477                 fhout = dup(fdout[1]);
 478         else if (cmd->out > 1)
 479                 fhout = dup(cmd->out);
 480
 481         if (cmd->env)
 482                 env = make_augmented_environ(cmd->env);
 483
 484         if (cmd->git_cmd) {
 485                 cmd->argv = prepare_git_cmd(cmd->argv);
 486         } else if (cmd->use_shell) {
 487                 cmd->argv = prepare_shell_cmd(cmd->argv);
 488         }
 489
 490         cmd->pid = mingw_spawnvpe(cmd->argv[0], cmd->argv, env, cmd->dir,
 491                                   fhin, fhout, fherr);
 492         failed_errno = errno;
 493         if (cmd->pid < 0 && (!cmd->silent_exec_failure || errno != ENOENT))
 494                 error("cannot spawn %s: %s", cmd->argv[0], strerror(errno));
 495         if (cmd->clean_on_exit && cmd->pid >= 0)
 496                 mark_child_for_cleanup(cmd->pid);
 497
 498         if (cmd->env)
 499                 free_environ(env);
 500         if (cmd->git_cmd)
 501                 free(cmd->argv);
 502
 503         cmd->argv = sargv;
 504         if (fhin != 0)
 505                 close(fhin);
 506         if (fhout != 1)
 507                 close(fhout);
 508         if (fherr != 2)
 509                 close(fherr);
 510 }
 511 #endif
 512
 513         if (cmd->pid < 0) {
 514                 if (need_in)
 515                         close_pair(fdin);
 516                 else if (cmd->in)
 517                         close(cmd->in);
 518                 if (need_out)
 519                         close_pair(fdout);
 520                 else if (cmd->out)
 521                         close(cmd->out);
 522                 if (need_err)
 523                         close_pair(fderr);
 524                 else if (cmd->err)
 525                         close(cmd->err);
 526                 errno = failed_errno;
 527                 return -1;
 528         }
 529
 530         if (need_in)
 531                 close(fdin[0]);
 532         else if (cmd->in)
 533                 close(cmd->in);
 534
 535         if (need_out)
 536                 close(fdout[1]);
 537         else if (cmd->out)
 538                 close(cmd->out);
 539
 540         if (need_err)
 541                 close(fderr[1]);
 542         else if (cmd->err)
 543                 close(cmd->err);
 544
 545         return 0;
 546 }
 547
 548 int finish_command(struct child_process *cmd)
 549 {
 550         return wait_or_whine(cmd->pid, cmd->argv[0], cmd->silent_exec_failure);
 551 }
 552
 553 int run_command(struct child_process *cmd)
 554 {
 555         int code = start_command(cmd);
 556         if (code)
 557                 return code;
 558         return finish_command(cmd);
 559 }
 560
 561 static void prepare_run_command_v_opt(struct child_process *cmd,
 562                                       const char **argv,
 563                                       int opt)
 564 {
 565         memset(cmd, 0, sizeof(*cmd));
 566         cmd->argv = argv;
 567         cmd->no_stdin = opt & RUN_COMMAND_NO_STDIN ? 1 : 0;
 568         cmd->git_cmd = opt & RUN_GIT_CMD ? 1 : 0;
 569         cmd->stdout_to_stderr = opt & RUN_COMMAND_STDOUT_TO_STDERR ? 1 : 0;
 570         cmd->silent_exec_failure = opt & RUN_SILENT_EXEC_FAILURE ? 1 : 0;
 571         cmd->use_shell = opt & RUN_USING_SHELL ? 1 : 0;
 572         cmd->clean_on_exit = opt & RUN_CLEAN_ON_EXIT ? 1 : 0;
 573 }
 574
 575 int run_command_v_opt(const char **argv, int opt)
 576 {
 577         struct child_process cmd;
 578         prepare_run_command_v_opt(&cmd, argv, opt);
 579         return run_command(&cmd);
 580 }
 581
 582 int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env)
 583 {
 584         struct child_process cmd;
 585         prepare_run_command_v_opt(&cmd, argv, opt);
 586         cmd.dir = dir;
 587         cmd.env = env;
 588         return run_command(&cmd);
 589 }
 590
 591 #ifndef NO_PTHREADS
 592 static pthread_t main_thread;
 593 static int main_thread_set;
 594 static pthread_key_t async_key;
 595
 596 static void *run_thread(void *data)
 597 {
 598         struct async *async = data;
 599         intptr_t ret;
 600
 601         pthread_setspecific(async_key, async);
 602         ret = async->proc(async->proc_in, async->proc_out, async->data);
 603         return (void *)ret;
 604 }
 605
 606 static NORETURN void die_async(const char *err, va_list params)
 607 {
 608         vreportf("fatal: ", err, params);
 609
 610         if (!pthread_equal(main_thread, pthread_self())) {
 611                 struct async *async = pthread_getspecific(async_key);
 612                 if (async->proc_in >= 0)
 613                         close(async->proc_in);
 614                 if (async->proc_out >= 0)
 615                         close(async->proc_out);
 616                 pthread_exit((void *)128);
 617         }
 618
 619         exit(128);
 620 }
 621 #endif
 622
 623 int start_async(struct async *async)
 624 {
 625         int need_in, need_out;
 626         int fdin[2], fdout[2];
 627         int proc_in, proc_out;
 628
 629         need_in = async->in < 0;
 630         if (need_in) {
 631                 if (pipe(fdin) < 0) {
 632                         if (async->out > 0)
 633                                 close(async->out);
 634                         return error("cannot create pipe: %s", strerror(errno));
 635                 }
 636                 async->in = fdin[1];
 637         }
 638
 639         need_out = async->out < 0;
 640         if (need_out) {
 641                 if (pipe(fdout) < 0) {
 642                         if (need_in)
 643                                 close_pair(fdin);
 644                         else if (async->in)
 645                                 close(async->in);
 646                         return error("cannot create pipe: %s", strerror(errno));
 647                 }
 648                 async->out = fdout[0];
 649         }
 650
 651         if (need_in)
 652                 proc_in = fdin[0];
 653         else if (async->in)
 654                 proc_in = async->in;
 655         else
 656                 proc_in = -1;
 657
 658         if (need_out)
 659                 proc_out = fdout[1];
 660         else if (async->out)
 661                 proc_out = async->out;
 662         else
 663                 proc_out = -1;
 664
 665 #ifdef NO_PTHREADS
 666         /* Flush stdio before fork() to avoid cloning buffers */
 667         fflush(NULL);
 668
 669         async->pid = fork();
 670         if (async->pid < 0) {
 671                 error("fork (async) failed: %s", strerror(errno));
 672                 goto error;
 673         }
 674         if (!async->pid) {
 675                 if (need_in)
 676                         close(fdin[1]);
 677                 if (need_out)
 678                         close(fdout[0]);
 679                 exit(!!async->proc(proc_in, proc_out, async->data));
 680         }
 681
 682         mark_child_for_cleanup(async->pid);
 683
 684         if (need_in)
 685                 close(fdin[0]);
 686         else if (async->in)
 687                 close(async->in);
 688
 689         if (need_out)
 690                 close(fdout[1]);
 691         else if (async->out)
 692                 close(async->out);
 693 #else
 694         if (!main_thread_set) {
 695                 /*
 696                  * We assume that the first time that start_async is called
 697                  * it is from the main thread.
 698                  */
 699                 main_thread_set = 1;
 700                 main_thread = pthread_self();
 701                 pthread_key_create(&async_key, NULL);
 702                 set_die_routine(die_async);
 703         }
 704
 705         if (proc_in >= 0)
 706                 set_cloexec(proc_in);
 707         if (proc_out >= 0)
 708                 set_cloexec(proc_out);
 709         async->proc_in = proc_in;
 710         async->proc_out = proc_out;
 711         {
 712                 int err = pthread_create(&async->tid, NULL, run_thread, async);
 713                 if (err) {
 714                         error("cannot create thread: %s", strerror(err));
 715                         goto error;
 716                 }
 717         }
 718 #endif
 719         return 0;
 720
 721 error:
 722         if (need_in)
 723                 close_pair(fdin);
 724         else if (async->in)
 725                 close(async->in);
 726
 727         if (need_out)
 728                 close_pair(fdout);
 729         else if (async->out)
 730                 close(async->out);
 731         return -1;
 732 }
 733
 734 int finish_async(struct async *async)
 735 {
 736 #ifdef NO_PTHREADS
 737         return wait_or_whine(async->pid, "child process", 0);
 738 #else
 739         void *ret = (void *)(intptr_t)(-1);
 740
 741         if (pthread_join(async->tid, &ret))
 742                 error("pthread_join failed");
 743         return (int)(intptr_t)ret;
 744 #endif
 745 }
 746
 747 int run_hook(const char *index_file, const char *name, ...)
 748 {
 749         struct child_process hook;
 750         struct argv_array argv = ARGV_ARRAY_INIT;
 751         const char *p, *env[2];
 752         char index[PATH_MAX];
 753         va_list args;
 754         int ret;
 755
 756         if (access(git_path("hooks/%s", name), X_OK) < 0)
 757                 return 0;
 758
 759         va_start(args, name);
 760         argv_array_push(&argv, git_path("hooks/%s", name));
 761         while ((p = va_arg(args, const char *)))
 762                 argv_array_push(&argv, p);
 763         va_end(args);
 764
 765         memset(&hook, 0, sizeof(hook));
 766         hook.argv = argv.argv;
 767         hook.no_stdin = 1;
 768         hook.stdout_to_stderr = 1;
 769         if (index_file) {
 770                 snprintf(index, sizeof(index), "GIT_INDEX_FILE=%s", index_file);
 771                 env[0] = index;
 772                 env[1] = NULL;
 773                 hook.env = env;
 774         }
 775
 776         ret = run_command(&hook);
 777         argv_array_clear(&argv);
 778         return ret;
 779 }