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