builtin/clone.c

   1 /*
   2  * Builtin "git clone"
   3  *
   4  * Copyright (c) 2007 Kristian Høgsberg <krh@redhat.com>,
   5  *               2008 Daniel Barkalow <barkalow@iabervon.org>
   6  * Based on git-commit.sh by Junio C Hamano and Linus Torvalds
   7  *
   8  * Clone a repository into a different directory that does not yet exist.
   9  */
  10
  11 #include "cache.h"
  12 #include "parse-options.h"
  13 #include "fetch-pack.h"
  14 #include "refs.h"
  15 #include "tree.h"
  16 #include "tree-walk.h"
  17 #include "unpack-trees.h"
  18 #include "transport.h"
  19 #include "strbuf.h"
  20 #include "dir.h"
  21 #include "pack-refs.h"
  22 #include "sigchain.h"
  23 #include "branch.h"
  24 #include "remote.h"
  25 #include "run-command.h"
  26
  27 /*
  28  * Overall FIXMEs:
  29  *  - respect DB_ENVIRONMENT for .git/objects.
  30  *
  31  * Implementation notes:
  32  *  - dropping use-separate-remote and no-separate-remote compatibility
  33  *
  34  */
  35 static const char * const builtin_clone_usage[] = {
  36         "git clone [options] [--] <repo> [<dir>]",
  37         NULL
  38 };
  39
  40 static int option_no_checkout, option_bare, option_mirror;
  41 static int option_local, option_no_hardlinks, option_shared, option_recursive;
  42 static char *option_template, *option_reference, *option_depth;
  43 static char *option_origin = NULL;
  44 static char *option_branch = NULL;
  45 static const char *real_git_dir;
  46 static char *option_upload_pack = "git-upload-pack";
  47 static int option_verbosity;
  48 static int option_progress;
  49
  50 static struct option builtin_clone_options[] = {
  51         OPT__VERBOSITY(&option_verbosity),
  52         OPT_BOOLEAN(0, "progress", &option_progress,
  53                         "force progress reporting"),
  54         OPT_BOOLEAN('n', "no-checkout", &option_no_checkout,
  55                     "don't create a checkout"),
  56         OPT_BOOLEAN(0, "bare", &option_bare, "create a bare repository"),
  57         { OPTION_BOOLEAN, 0, "naked", &option_bare, NULL,
  58                 "create a bare repository",
  59                 PARSE_OPT_NOARG | PARSE_OPT_HIDDEN },
  60         OPT_BOOLEAN(0, "mirror", &option_mirror,
  61                     "create a mirror repository (implies bare)"),
  62         OPT_BOOLEAN('l', "local", &option_local,
  63                     "to clone from a local repository"),
  64         OPT_BOOLEAN(0, "no-hardlinks", &option_no_hardlinks,
  65                     "don't use local hardlinks, always copy"),
  66         OPT_BOOLEAN('s', "shared", &option_shared,
  67                     "setup as shared repository"),
  68         OPT_BOOLEAN(0, "recursive", &option_recursive,
  69                     "initialize submodules in the clone"),
  70         OPT_BOOLEAN(0, "recurse-submodules", &option_recursive,
  71                     "initialize submodules in the clone"),
  72         OPT_STRING(0, "template", &option_template, "template-directory",
  73                    "directory from which templates will be used"),
  74         OPT_STRING(0, "reference", &option_reference, "repo",
  75                    "reference repository"),
  76         OPT_STRING('o', "origin", &option_origin, "branch",
  77                    "use <branch> instead of 'origin' to track upstream"),
  78         OPT_STRING('b', "branch", &option_branch, "branch",
  79                    "checkout <branch> instead of the remote's HEAD"),
  80         OPT_STRING('u', "upload-pack", &option_upload_pack, "path",
  81                    "path to git-upload-pack on the remote"),
  82         OPT_STRING(0, "depth", &option_depth, "depth",
  83                     "create a shallow clone of that depth"),
  84         OPT_STRING('L', "separate-git-dir", &real_git_dir, "gitdir",
  85                    "separate git dir from working tree"),
  86
  87         OPT_END()
  88 };
  89
  90 static const char *argv_submodule[] = {
  91         "submodule", "update", "--init", "--recursive", NULL
  92 };
  93
  94 static char *get_repo_path(const char *repo, int *is_bundle)
  95 {
  96         static char *suffix[] = { "/.git", ".git", "" };
  97         static char *bundle_suffix[] = { ".bundle", "" };
  98         struct stat st;
  99         int i;
 100
 101         for (i = 0; i < ARRAY_SIZE(suffix); i++) {
 102                 const char *path;
 103                 path = mkpath("%s%s", repo, suffix[i]);
 104                 if (is_directory(path)) {
 105                         *is_bundle = 0;
 106                         return xstrdup(absolute_path(path));
 107                 }
 108         }
 109
 110         for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
 111                 const char *path;
 112                 path = mkpath("%s%s", repo, bundle_suffix[i]);
 113                 if (!stat(path, &st) && S_ISREG(st.st_mode)) {
 114                         *is_bundle = 1;
 115                         return xstrdup(absolute_path(path));
 116                 }
 117         }
 118
 119         return NULL;
 120 }
 121
 122 static char *guess_dir_name(const char *repo, int is_bundle, int is_bare)
 123 {
 124         const char *end = repo + strlen(repo), *start;
 125         char *dir;
 126
 127         /*
 128          * Strip trailing spaces, slashes and /.git
 129          */
 130         while (repo < end && (is_dir_sep(end[-1]) || isspace(end[-1])))
 131                 end--;
 132         if (end - repo > 5 && is_dir_sep(end[-5]) &&
 133             !strncmp(end - 4, ".git", 4)) {
 134                 end -= 5;
 135                 while (repo < end && is_dir_sep(end[-1]))
 136                         end--;
 137         }
 138
 139         /*
 140          * Find last component, but be prepared that repo could have
 141          * the form  "remote.example.com:foo.git", i.e. no slash
 142          * in the directory part.
 143          */
 144         start = end;
 145         while (repo < start && !is_dir_sep(start[-1]) && start[-1] != ':')
 146                 start--;
 147
 148         /*
 149          * Strip .{bundle,git}.
 150          */
 151         if (is_bundle) {
 152                 if (end - start > 7 && !strncmp(end - 7, ".bundle", 7))
 153                         end -= 7;
 154         } else {
 155                 if (end - start > 4 && !strncmp(end - 4, ".git", 4))
 156                         end -= 4;
 157         }
 158
 159         if (is_bare) {
 160                 struct strbuf result = STRBUF_INIT;
 161                 strbuf_addf(&result, "%.*s.git", (int)(end - start), start);
 162                 dir = strbuf_detach(&result, NULL);
 163         } else
 164                 dir = xstrndup(start, end - start);
 165         /*
 166          * Replace sequences of 'control' characters and whitespace
 167          * with one ascii space, remove leading and trailing spaces.
 168          */
 169         if (*dir) {
 170                 char *out = dir;
 171                 int prev_space = 1 /* strip leading whitespace */;
 172                 for (end = dir; *end; ++end) {
 173                         char ch = *end;
 174                         if ((unsigned char)ch < '\x20')
 175                                 ch = '\x20';
 176                         if (isspace(ch)) {
 177                                 if (prev_space)
 178                                         continue;
 179                                 prev_space = 1;
 180                         } else
 181                                 prev_space = 0;
 182                         *out++ = ch;
 183                 }
 184                 *out = '\0';
 185                 if (out > dir && prev_space)
 186                         out[-1] = '\0';
 187         }
 188         return dir;
 189 }
 190
 191 static void strip_trailing_slashes(char *dir)
 192 {
 193         char *end = dir + strlen(dir);
 194
 195         while (dir < end - 1 && is_dir_sep(end[-1]))
 196                 end--;
 197         *end = '\0';
 198 }
 199
 200 static void setup_reference(const char *repo)
 201 {
 202         const char *ref_git;
 203         char *ref_git_copy;
 204
 205         struct remote *remote;
 206         struct transport *transport;
 207         const struct ref *extra;
 208
 209         ref_git = real_path(option_reference);
 210
 211         if (is_directory(mkpath("%s/.git/objects", ref_git)))
 212                 ref_git = mkpath("%s/.git", ref_git);
 213         else if (!is_directory(mkpath("%s/objects", ref_git)))
 214                 die("reference repository '%s' is not a local directory.",
 215                     option_reference);
 216
 217         ref_git_copy = xstrdup(ref_git);
 218
 219         add_to_alternates_file(ref_git_copy);
 220
 221         remote = remote_get(ref_git_copy);
 222         transport = transport_get(remote, ref_git_copy);
 223         for (extra = transport_get_remote_refs(transport); extra;
 224              extra = extra->next)
 225                 add_extra_ref(extra->name, extra->old_sha1, 0);
 226
 227         transport_disconnect(transport);
 228
 229         free(ref_git_copy);
 230 }
 231
 232 static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest)
 233 {
 234         struct dirent *de;
 235         struct stat buf;
 236         int src_len, dest_len;
 237         DIR *dir;
 238
 239         dir = opendir(src->buf);
 240         if (!dir)
 241                 die_errno("failed to open '%s'", src->buf);
 242
 243         if (mkdir(dest->buf, 0777)) {
 244                 if (errno != EEXIST)
 245                         die_errno("failed to create directory '%s'", dest->buf);
 246                 else if (stat(dest->buf, &buf))
 247                         die_errno("failed to stat '%s'", dest->buf);
 248                 else if (!S_ISDIR(buf.st_mode))
 249                         die("%s exists and is not a directory", dest->buf);
 250         }
 251
 252         strbuf_addch(src, '/');
 253         src_len = src->len;
 254         strbuf_addch(dest, '/');
 255         dest_len = dest->len;
 256
 257         while ((de = readdir(dir)) != NULL) {
 258                 strbuf_setlen(src, src_len);
 259                 strbuf_addstr(src, de->d_name);
 260                 strbuf_setlen(dest, dest_len);
 261                 strbuf_addstr(dest, de->d_name);
 262                 if (stat(src->buf, &buf)) {
 263                         warning ("failed to stat %s\n", src->buf);
 264                         continue;
 265                 }
 266                 if (S_ISDIR(buf.st_mode)) {
 267                         if (de->d_name[0] != '.')
 268                                 copy_or_link_directory(src, dest);
 269                         continue;
 270                 }
 271
 272                 if (unlink(dest->buf) && errno != ENOENT)
 273                         die_errno("failed to unlink '%s'", dest->buf);
 274                 if (!option_no_hardlinks) {
 275                         if (!link(src->buf, dest->buf))
 276                                 continue;
 277                         if (option_local)
 278                                 die_errno("failed to create link '%s'", dest->buf);
 279                         option_no_hardlinks = 1;
 280                 }
 281                 if (copy_file_with_time(dest->buf, src->buf, 0666))
 282                         die_errno("failed to copy file to '%s'", dest->buf);
 283         }
 284         closedir(dir);
 285 }
 286
 287 static const struct ref *clone_local(const char *src_repo,
 288                                      const char *dest_repo)
 289 {
 290         const struct ref *ret;
 291         struct strbuf src = STRBUF_INIT;
 292         struct strbuf dest = STRBUF_INIT;
 293         struct remote *remote;
 294         struct transport *transport;
 295
 296         if (option_shared)
 297                 add_to_alternates_file(src_repo);
 298         else {
 299                 strbuf_addf(&src, "%s/objects", src_repo);
 300                 strbuf_addf(&dest, "%s/objects", dest_repo);
 301                 copy_or_link_directory(&src, &dest);
 302                 strbuf_release(&src);
 303                 strbuf_release(&dest);
 304         }
 305
 306         remote = remote_get(src_repo);
 307         transport = transport_get(remote, src_repo);
 308         ret = transport_get_remote_refs(transport);
 309         transport_disconnect(transport);
 310         if (0 <= option_verbosity)
 311                 printf("done.\n");
 312         return ret;
 313 }
 314
 315 static const char *junk_work_tree;
 316 static const char *junk_git_dir;
 317 static pid_t junk_pid;
 318
 319 static void remove_junk(void)
 320 {
 321         struct strbuf sb = STRBUF_INIT;
 322         if (getpid() != junk_pid)
 323                 return;
 324         if (junk_git_dir) {
 325                 strbuf_addstr(&sb, junk_git_dir);
 326                 remove_dir_recursively(&sb, 0);
 327                 strbuf_reset(&sb);
 328         }
 329         if (junk_work_tree) {
 330                 strbuf_addstr(&sb, junk_work_tree);
 331                 remove_dir_recursively(&sb, 0);
 332                 strbuf_reset(&sb);
 333         }
 334 }
 335
 336 static void remove_junk_on_signal(int signo)
 337 {
 338         remove_junk();
 339         sigchain_pop(signo);
 340         raise(signo);
 341 }
 342
 343 static struct ref *wanted_peer_refs(const struct ref *refs,
 344                 struct refspec *refspec)
 345 {
 346         struct ref *local_refs = NULL;
 347         struct ref **tail = &local_refs;
 348
 349         get_fetch_map(refs, refspec, &tail, 0);
 350         if (!option_mirror)
 351                 get_fetch_map(refs, tag_refspec, &tail, 0);
 352
 353         return local_refs;
 354 }
 355
 356 static void write_remote_refs(const struct ref *local_refs)
 357 {
 358         const struct ref *r;
 359
 360         for (r = local_refs; r; r = r->next)
 361                 add_extra_ref(r->peer_ref->name, r->old_sha1, 0);
 362
 363         pack_refs(PACK_REFS_ALL);
 364         clear_extra_refs();
 365 }
 366
 367 int cmd_clone(int argc, const char **argv, const char *prefix)
 368 {
 369         int is_bundle = 0, is_local;
 370         struct stat buf;
 371         const char *repo_name, *repo, *work_tree, *git_dir;
 372         char *path, *dir;
 373         int dest_exists;
 374         const struct ref *refs, *remote_head;
 375         const struct ref *remote_head_points_at;
 376         const struct ref *our_head_points_at;
 377         struct ref *mapped_refs;
 378         struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
 379         struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
 380         struct transport *transport = NULL;
 381         char *src_ref_prefix = "refs/heads/";
 382         int err = 0;
 383
 384         struct refspec *refspec;
 385         const char *fetch_pattern;
 386
 387         junk_pid = getpid();
 388
 389         argc = parse_options(argc, argv, prefix, builtin_clone_options,
 390                              builtin_clone_usage, 0);
 391
 392         if (argc > 2)
 393                 usage_msg_opt("Too many arguments.",
 394                         builtin_clone_usage, builtin_clone_options);
 395
 396         if (argc == 0)
 397                 usage_msg_opt("You must specify a repository to clone.",
 398                         builtin_clone_usage, builtin_clone_options);
 399
 400         if (option_mirror)
 401                 option_bare = 1;
 402
 403         if (option_bare) {
 404                 if (option_origin)
 405                         die("--bare and --origin %s options are incompatible.",
 406                             option_origin);
 407                 option_no_checkout = 1;
 408         }
 409
 410         if (!option_origin)
 411                 option_origin = "origin";
 412
 413         repo_name = argv[0];
 414
 415         path = get_repo_path(repo_name, &is_bundle);
 416         if (path)
 417                 repo = xstrdup(absolute_path(repo_name));
 418         else if (!strchr(repo_name, ':'))
 419                 die("repository '%s' does not exist", repo_name);
 420         else
 421                 repo = repo_name;
 422         is_local = path && !is_bundle;
 423         if (is_local && option_depth)
 424                 warning("--depth is ignored in local clones; use file:// instead.");
 425
 426         if (argc == 2)
 427                 dir = xstrdup(argv[1]);
 428         else
 429                 dir = guess_dir_name(repo_name, is_bundle, option_bare);
 430         strip_trailing_slashes(dir);
 431
 432         dest_exists = !stat(dir, &buf);
 433         if (dest_exists && !is_empty_dir(dir))
 434                 die("destination path '%s' already exists and is not "
 435                         "an empty directory.", dir);
 436
 437         strbuf_addf(&reflog_msg, "clone: from %s", repo);
 438
 439         if (option_bare)
 440                 work_tree = NULL;
 441         else {
 442                 work_tree = getenv("GIT_WORK_TREE");
 443                 if (work_tree && !stat(work_tree, &buf))
 444                         die("working tree '%s' already exists.", work_tree);
 445         }
 446
 447         if (option_bare || work_tree)
 448                 git_dir = xstrdup(dir);
 449         else {
 450                 work_tree = dir;
 451                 git_dir = xstrdup(mkpath("%s/.git", dir));
 452         }
 453
 454         if (!option_bare) {
 455                 junk_work_tree = work_tree;
 456                 if (safe_create_leading_directories_const(work_tree) < 0)
 457                         die_errno("could not create leading directories of '%s'",
 458                                   work_tree);
 459                 if (!dest_exists && mkdir(work_tree, 0755))
 460                         die_errno("could not create work tree dir '%s'.",
 461                                   work_tree);
 462                 set_git_work_tree(work_tree);
 463         }
 464         junk_git_dir = git_dir;
 465         atexit(remove_junk);
 466         sigchain_push_common(remove_junk_on_signal);
 467
 468         setenv(CONFIG_ENVIRONMENT, mkpath("%s/config", git_dir), 1);
 469
 470         if (safe_create_leading_directories_const(git_dir) < 0)
 471                 die("could not create leading directories of '%s'", git_dir);
 472
 473         set_git_dir_init(git_dir, real_git_dir, 0);
 474         if (real_git_dir)
 475                 git_dir = real_git_dir;
 476
 477         if (0 <= option_verbosity)
 478                 printf("Cloning into %s%s...\n",
 479                        option_bare ? "bare repository " : "", dir);
 480         init_db(option_template, INIT_DB_QUIET);
 481
 482         /*
 483          * At this point, the config exists, so we do not need the
 484          * environment variable.  We actually need to unset it, too, to
 485          * re-enable parsing of the global configs.
 486          */
 487         unsetenv(CONFIG_ENVIRONMENT);
 488
 489         git_config(git_default_config, NULL);
 490
 491         if (option_bare) {
 492                 if (option_mirror)
 493                         src_ref_prefix = "refs/";
 494                 strbuf_addstr(&branch_top, src_ref_prefix);
 495
 496                 git_config_set("core.bare", "true");
 497         } else {
 498                 strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
 499         }
 500
 501         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top.buf);
 502
 503         if (option_mirror || !option_bare) {
 504                 /* Configure the remote */
 505                 strbuf_addf(&key, "remote.%s.fetch", option_origin);
 506                 git_config_set_multivar(key.buf, value.buf, "^$", 0);
 507                 strbuf_reset(&key);
 508
 509                 if (option_mirror) {
 510                         strbuf_addf(&key, "remote.%s.mirror", option_origin);
 511                         git_config_set(key.buf, "true");
 512                         strbuf_reset(&key);
 513                 }
 514         }
 515
 516         strbuf_addf(&key, "remote.%s.url", option_origin);
 517         git_config_set(key.buf, repo);
 518         strbuf_reset(&key);
 519
 520         if (option_reference)
 521                 setup_reference(git_dir);
 522
 523         fetch_pattern = value.buf;
 524         refspec = parse_fetch_refspec(1, &fetch_pattern);
 525
 526         strbuf_reset(&value);
 527
 528         if (is_local) {
 529                 refs = clone_local(path, git_dir);
 530                 mapped_refs = wanted_peer_refs(refs, refspec);
 531         } else {
 532                 struct remote *remote = remote_get(option_origin);
 533                 transport = transport_get(remote, remote->url[0]);
 534
 535                 if (!transport->get_refs_list || !transport->fetch)
 536                         die("Don't know how to clone %s", transport->url);
 537
 538                 transport_set_option(transport, TRANS_OPT_KEEP, "yes");
 539
 540                 if (option_depth)
 541                         transport_set_option(transport, TRANS_OPT_DEPTH,
 542                                              option_depth);
 543
 544                 transport_set_verbosity(transport, option_verbosity, option_progress);
 545
 546                 if (option_upload_pack)
 547                         transport_set_option(transport, TRANS_OPT_UPLOADPACK,
 548                                              option_upload_pack);
 549
 550                 refs = transport_get_remote_refs(transport);
 551                 if (refs) {
 552                         mapped_refs = wanted_peer_refs(refs, refspec);
 553                         transport_fetch_refs(transport, mapped_refs);
 554                 }
 555         }
 556
 557         if (refs) {
 558                 clear_extra_refs();
 559
 560                 write_remote_refs(mapped_refs);
 561
 562                 remote_head = find_ref_by_name(refs, "HEAD");
 563                 remote_head_points_at =
 564                         guess_remote_head(remote_head, mapped_refs, 0);
 565
 566                 if (option_branch) {
 567                         struct strbuf head = STRBUF_INIT;
 568                         strbuf_addstr(&head, src_ref_prefix);
 569                         strbuf_addstr(&head, option_branch);
 570                         our_head_points_at =
 571                                 find_ref_by_name(mapped_refs, head.buf);
 572                         strbuf_release(&head);
 573
 574                         if (!our_head_points_at) {
 575                                 warning("Remote branch %s not found in "
 576                                         "upstream %s, using HEAD instead",
 577                                         option_branch, option_origin);
 578                                 our_head_points_at = remote_head_points_at;
 579                         }
 580                 }
 581                 else
 582                         our_head_points_at = remote_head_points_at;
 583         }
 584         else {
 585                 warning("You appear to have cloned an empty repository.");
 586                 our_head_points_at = NULL;
 587                 remote_head_points_at = NULL;
 588                 remote_head = NULL;
 589                 option_no_checkout = 1;
 590                 if (!option_bare)
 591                         install_branch_config(0, "master", option_origin,
 592                                               "refs/heads/master");
 593         }
 594
 595         if (remote_head_points_at && !option_bare) {
 596                 struct strbuf head_ref = STRBUF_INIT;
 597                 strbuf_addstr(&head_ref, branch_top.buf);
 598                 strbuf_addstr(&head_ref, "HEAD");
 599                 create_symref(head_ref.buf,
 600                               remote_head_points_at->peer_ref->name,
 601                               reflog_msg.buf);
 602         }
 603
 604         if (our_head_points_at) {
 605                 /* Local default branch link */
 606                 create_symref("HEAD", our_head_points_at->name, NULL);
 607                 if (!option_bare) {
 608                         const char *head = skip_prefix(our_head_points_at->name,
 609                                                        "refs/heads/");
 610                         update_ref(reflog_msg.buf, "HEAD",
 611                                    our_head_points_at->old_sha1,
 612                                    NULL, 0, DIE_ON_ERR);
 613                         install_branch_config(0, head, option_origin,
 614                                               our_head_points_at->name);
 615                 }
 616         } else if (remote_head) {
 617                 /* Source had detached HEAD pointing somewhere. */
 618                 if (!option_bare) {
 619                         update_ref(reflog_msg.buf, "HEAD",
 620                                    remote_head->old_sha1,
 621                                    NULL, REF_NODEREF, DIE_ON_ERR);
 622                         our_head_points_at = remote_head;
 623                 }
 624         } else {
 625                 /* Nothing to checkout out */
 626                 if (!option_no_checkout)
 627                         warning("remote HEAD refers to nonexistent ref, "
 628                                 "unable to checkout.\n");
 629                 option_no_checkout = 1;
 630         }
 631
 632         if (transport) {
 633                 transport_unlock_pack(transport);
 634                 transport_disconnect(transport);
 635         }
 636
 637         if (!option_no_checkout) {
 638                 struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
 639                 struct unpack_trees_options opts;
 640                 struct tree *tree;
 641                 struct tree_desc t;
 642                 int fd;
 643
 644                 /* We need to be in the new work tree for the checkout */
 645                 setup_work_tree();
 646
 647                 fd = hold_locked_index(lock_file, 1);
 648
 649                 memset(&opts, 0, sizeof opts);
 650                 opts.update = 1;
 651                 opts.merge = 1;
 652                 opts.fn = oneway_merge;
 653                 opts.verbose_update = (option_verbosity > 0);
 654                 opts.src_index = &the_index;
 655                 opts.dst_index = &the_index;
 656
 657                 tree = parse_tree_indirect(our_head_points_at->old_sha1);
 658                 parse_tree(tree);
 659                 init_tree_desc(&t, tree->buffer, tree->size);
 660                 unpack_trees(1, &t, &opts);
 661
 662                 if (write_cache(fd, active_cache, active_nr) ||
 663                     commit_locked_index(lock_file))
 664                         die("unable to write new index file");
 665
 666                 err |= run_hook(NULL, "post-checkout", sha1_to_hex(null_sha1),
 667                                 sha1_to_hex(our_head_points_at->old_sha1), "1",
 668                                 NULL);
 669
 670                 if (!err && option_recursive)
 671                         err = run_command_v_opt(argv_submodule, RUN_GIT_CMD);
 672         }
 673
 674         strbuf_release(&reflog_msg);
 675         strbuf_release(&branch_top);
 676         strbuf_release(&key);
 677         strbuf_release(&value);
 678         junk_pid = 0;
 679         return err;
 680 }