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, option_single_branch = -1;
  41 static int option_local, option_no_hardlinks, option_shared, option_recursive;
  42 static char *option_template, *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 static struct string_list option_config;
  50 static struct string_list option_reference;
  51 static const char *src_ref_prefix = "refs/heads/";
  52
  53 static int opt_parse_reference(const struct option *opt, const char *arg, int unset)
  54 {
  55         struct string_list *option_reference = opt->value;
  56         if (!arg)
  57                 return -1;
  58         string_list_append(option_reference, arg);
  59         return 0;
  60 }
  61
  62 static struct option builtin_clone_options[] = {
  63         OPT__VERBOSITY(&option_verbosity),
  64         OPT_BOOLEAN(0, "progress", &option_progress,
  65                         "force progress reporting"),
  66         OPT_BOOLEAN('n', "no-checkout", &option_no_checkout,
  67                     "don't create a checkout"),
  68         OPT_BOOLEAN(0, "bare", &option_bare, "create a bare repository"),
  69         { OPTION_BOOLEAN, 0, "naked", &option_bare, NULL,
  70                 "create a bare repository",
  71                 PARSE_OPT_NOARG | PARSE_OPT_HIDDEN },
  72         OPT_BOOLEAN(0, "mirror", &option_mirror,
  73                     "create a mirror repository (implies bare)"),
  74         OPT_BOOLEAN('l', "local", &option_local,
  75                     "to clone from a local repository"),
  76         OPT_BOOLEAN(0, "no-hardlinks", &option_no_hardlinks,
  77                     "don't use local hardlinks, always copy"),
  78         OPT_BOOLEAN('s', "shared", &option_shared,
  79                     "setup as shared repository"),
  80         OPT_BOOLEAN(0, "recursive", &option_recursive,
  81                     "initialize submodules in the clone"),
  82         OPT_BOOLEAN(0, "recurse-submodules", &option_recursive,
  83                     "initialize submodules in the clone"),
  84         OPT_STRING(0, "template", &option_template, "template-directory",
  85                    "directory from which templates will be used"),
  86         OPT_CALLBACK(0 , "reference", &option_reference, "repo",
  87                      "reference repository", &opt_parse_reference),
  88         OPT_STRING('o', "origin", &option_origin, "name",
  89                    "use <name> instead of 'origin' to track upstream"),
  90         OPT_STRING('b', "branch", &option_branch, "branch",
  91                    "checkout <branch> instead of the remote's HEAD"),
  92         OPT_STRING('u', "upload-pack", &option_upload_pack, "path",
  93                    "path to git-upload-pack on the remote"),
  94         OPT_STRING(0, "depth", &option_depth, "depth",
  95                     "create a shallow clone of that depth"),
  96         OPT_BOOL(0, "single-branch", &option_single_branch,
  97                     "clone only one branch, HEAD or --branch"),
  98         OPT_STRING(0, "separate-git-dir", &real_git_dir, "gitdir",
  99                    "separate git dir from working tree"),
 100         OPT_STRING_LIST('c', "config", &option_config, "key=value",
 101                         "set config inside the new repository"),
 102         OPT_END()
 103 };
 104
 105 static const char *argv_submodule[] = {
 106         "submodule", "update", "--init", "--recursive", NULL
 107 };
 108
 109 static char *get_repo_path(const char *repo, int *is_bundle)
 110 {
 111         static char *suffix[] = { "/.git", ".git", "" };
 112         static char *bundle_suffix[] = { ".bundle", "" };
 113         struct stat st;
 114         int i;
 115
 116         for (i = 0; i < ARRAY_SIZE(suffix); i++) {
 117                 const char *path;
 118                 path = mkpath("%s%s", repo, suffix[i]);
 119                 if (stat(path, &st))
 120                         continue;
 121                 if (S_ISDIR(st.st_mode)) {
 122                         *is_bundle = 0;
 123                         return xstrdup(absolute_path(path));
 124                 } else if (S_ISREG(st.st_mode) && st.st_size > 8) {
 125                         /* Is it a "gitfile"? */
 126                         char signature[8];
 127                         int len, fd = open(path, O_RDONLY);
 128                         if (fd < 0)
 129                                 continue;
 130                         len = read_in_full(fd, signature, 8);
 131                         close(fd);
 132                         if (len != 8 || strncmp(signature, "gitdir: ", 8))
 133                                 continue;
 134                         path = read_gitfile(path);
 135                         if (path) {
 136                                 *is_bundle = 0;
 137                                 return xstrdup(absolute_path(path));
 138                         }
 139                 }
 140         }
 141
 142         for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
 143                 const char *path;
 144                 path = mkpath("%s%s", repo, bundle_suffix[i]);
 145                 if (!stat(path, &st) && S_ISREG(st.st_mode)) {
 146                         *is_bundle = 1;
 147                         return xstrdup(absolute_path(path));
 148                 }
 149         }
 150
 151         return NULL;
 152 }
 153
 154 static char *guess_dir_name(const char *repo, int is_bundle, int is_bare)
 155 {
 156         const char *end = repo + strlen(repo), *start;
 157         char *dir;
 158
 159         /*
 160          * Strip trailing spaces, slashes and /.git
 161          */
 162         while (repo < end && (is_dir_sep(end[-1]) || isspace(end[-1])))
 163                 end--;
 164         if (end - repo > 5 && is_dir_sep(end[-5]) &&
 165             !strncmp(end - 4, ".git", 4)) {
 166                 end -= 5;
 167                 while (repo < end && is_dir_sep(end[-1]))
 168                         end--;
 169         }
 170
 171         /*
 172          * Find last component, but be prepared that repo could have
 173          * the form  "remote.example.com:foo.git", i.e. no slash
 174          * in the directory part.
 175          */
 176         start = end;
 177         while (repo < start && !is_dir_sep(start[-1]) && start[-1] != ':')
 178                 start--;
 179
 180         /*
 181          * Strip .{bundle,git}.
 182          */
 183         if (is_bundle) {
 184                 if (end - start > 7 && !strncmp(end - 7, ".bundle", 7))
 185                         end -= 7;
 186         } else {
 187                 if (end - start > 4 && !strncmp(end - 4, ".git", 4))
 188                         end -= 4;
 189         }
 190
 191         if (is_bare) {
 192                 struct strbuf result = STRBUF_INIT;
 193                 strbuf_addf(&result, "%.*s.git", (int)(end - start), start);
 194                 dir = strbuf_detach(&result, NULL);
 195         } else
 196                 dir = xstrndup(start, end - start);
 197         /*
 198          * Replace sequences of 'control' characters and whitespace
 199          * with one ascii space, remove leading and trailing spaces.
 200          */
 201         if (*dir) {
 202                 char *out = dir;
 203                 int prev_space = 1 /* strip leading whitespace */;
 204                 for (end = dir; *end; ++end) {
 205                         char ch = *end;
 206                         if ((unsigned char)ch < '\x20')
 207                                 ch = '\x20';
 208                         if (isspace(ch)) {
 209                                 if (prev_space)
 210                                         continue;
 211                                 prev_space = 1;
 212                         } else
 213                                 prev_space = 0;
 214                         *out++ = ch;
 215                 }
 216                 *out = '\0';
 217                 if (out > dir && prev_space)
 218                         out[-1] = '\0';
 219         }
 220         return dir;
 221 }
 222
 223 static void strip_trailing_slashes(char *dir)
 224 {
 225         char *end = dir + strlen(dir);
 226
 227         while (dir < end - 1 && is_dir_sep(end[-1]))
 228                 end--;
 229         *end = '\0';
 230 }
 231
 232 static int add_one_reference(struct string_list_item *item, void *cb_data)
 233 {
 234         char *ref_git;
 235         struct strbuf alternate = STRBUF_INIT;
 236         struct remote *remote;
 237         struct transport *transport;
 238         const struct ref *extra;
 239
 240         /* Beware: real_path() and mkpath() return static buffer */
 241         ref_git = xstrdup(real_path(item->string));
 242         if (is_directory(mkpath("%s/.git/objects", ref_git))) {
 243                 char *ref_git_git = xstrdup(mkpath("%s/.git", ref_git));
 244                 free(ref_git);
 245                 ref_git = ref_git_git;
 246         } else if (!is_directory(mkpath("%s/objects", ref_git)))
 247                 die(_("reference repository '%s' is not a local directory."),
 248                     item->string);
 249
 250         strbuf_addf(&alternate, "%s/objects", ref_git);
 251         add_to_alternates_file(alternate.buf);
 252         strbuf_release(&alternate);
 253
 254         remote = remote_get(ref_git);
 255         transport = transport_get(remote, ref_git);
 256         for (extra = transport_get_remote_refs(transport); extra;
 257              extra = extra->next)
 258                 add_extra_ref(extra->name, extra->old_sha1, 0);
 259
 260         transport_disconnect(transport);
 261         free(ref_git);
 262         return 0;
 263 }
 264
 265 static void setup_reference(void)
 266 {
 267         for_each_string_list(&option_reference, add_one_reference, NULL);
 268 }
 269
 270 static void copy_alternates(struct strbuf *src, struct strbuf *dst,
 271                             const char *src_repo)
 272 {
 273         /*
 274          * Read from the source objects/info/alternates file
 275          * and copy the entries to corresponding file in the
 276          * destination repository with add_to_alternates_file().
 277          * Both src and dst have "$path/objects/info/alternates".
 278          *
 279          * Instead of copying bit-for-bit from the original,
 280          * we need to append to existing one so that the already
 281          * created entry via "clone -s" is not lost, and also
 282          * to turn entries with paths relative to the original
 283          * absolute, so that they can be used in the new repository.
 284          */
 285         FILE *in = fopen(src->buf, "r");
 286         struct strbuf line = STRBUF_INIT;
 287
 288         while (strbuf_getline(&line, in, '\n') != EOF) {
 289                 char *abs_path, abs_buf[PATH_MAX];
 290                 if (!line.len || line.buf[0] == '#')
 291                         continue;
 292                 if (is_absolute_path(line.buf)) {
 293                         add_to_alternates_file(line.buf);
 294                         continue;
 295                 }
 296                 abs_path = mkpath("%s/objects/%s", src_repo, line.buf);
 297                 normalize_path_copy(abs_buf, abs_path);
 298                 add_to_alternates_file(abs_buf);
 299         }
 300         strbuf_release(&line);
 301         fclose(in);
 302 }
 303
 304 static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
 305                                    const char *src_repo, int src_baselen)
 306 {
 307         struct dirent *de;
 308         struct stat buf;
 309         int src_len, dest_len;
 310         DIR *dir;
 311
 312         dir = opendir(src->buf);
 313         if (!dir)
 314                 die_errno(_("failed to open '%s'"), src->buf);
 315
 316         if (mkdir(dest->buf, 0777)) {
 317                 if (errno != EEXIST)
 318                         die_errno(_("failed to create directory '%s'"), dest->buf);
 319                 else if (stat(dest->buf, &buf))
 320                         die_errno(_("failed to stat '%s'"), dest->buf);
 321                 else if (!S_ISDIR(buf.st_mode))
 322                         die(_("%s exists and is not a directory"), dest->buf);
 323         }
 324
 325         strbuf_addch(src, '/');
 326         src_len = src->len;
 327         strbuf_addch(dest, '/');
 328         dest_len = dest->len;
 329
 330         while ((de = readdir(dir)) != NULL) {
 331                 strbuf_setlen(src, src_len);
 332                 strbuf_addstr(src, de->d_name);
 333                 strbuf_setlen(dest, dest_len);
 334                 strbuf_addstr(dest, de->d_name);
 335                 if (stat(src->buf, &buf)) {
 336                         warning (_("failed to stat %s\n"), src->buf);
 337                         continue;
 338                 }
 339                 if (S_ISDIR(buf.st_mode)) {
 340                         if (de->d_name[0] != '.')
 341                                 copy_or_link_directory(src, dest,
 342                                                        src_repo, src_baselen);
 343                         continue;
 344                 }
 345
 346                 /* Files that cannot be copied bit-for-bit... */
 347                 if (!strcmp(src->buf + src_baselen, "/info/alternates")) {
 348                         copy_alternates(src, dest, src_repo);
 349                         continue;
 350                 }
 351
 352                 if (unlink(dest->buf) && errno != ENOENT)
 353                         die_errno(_("failed to unlink '%s'"), dest->buf);
 354                 if (!option_no_hardlinks) {
 355                         if (!link(src->buf, dest->buf))
 356                                 continue;
 357                         if (option_local)
 358                                 die_errno(_("failed to create link '%s'"), dest->buf);
 359                         option_no_hardlinks = 1;
 360                 }
 361                 if (copy_file_with_time(dest->buf, src->buf, 0666))
 362                         die_errno(_("failed to copy file to '%s'"), dest->buf);
 363         }
 364         closedir(dir);
 365 }
 366
 367 static const struct ref *clone_local(const char *src_repo,
 368                                      const char *dest_repo)
 369 {
 370         const struct ref *ret;
 371         struct remote *remote;
 372         struct transport *transport;
 373
 374         if (option_shared) {
 375                 struct strbuf alt = STRBUF_INIT;
 376                 strbuf_addf(&alt, "%s/objects", src_repo);
 377                 add_to_alternates_file(alt.buf);
 378                 strbuf_release(&alt);
 379         } else {
 380                 struct strbuf src = STRBUF_INIT;
 381                 struct strbuf dest = STRBUF_INIT;
 382                 strbuf_addf(&src, "%s/objects", src_repo);
 383                 strbuf_addf(&dest, "%s/objects", dest_repo);
 384                 copy_or_link_directory(&src, &dest, src_repo, src.len);
 385                 strbuf_release(&src);
 386                 strbuf_release(&dest);
 387         }
 388
 389         remote = remote_get(src_repo);
 390         transport = transport_get(remote, src_repo);
 391         ret = transport_get_remote_refs(transport);
 392         transport_disconnect(transport);
 393         if (0 <= option_verbosity)
 394                 printf(_("done.\n"));
 395         return ret;
 396 }
 397
 398 static const char *junk_work_tree;
 399 static const char *junk_git_dir;
 400 static pid_t junk_pid;
 401
 402 static void remove_junk(void)
 403 {
 404         struct strbuf sb = STRBUF_INIT;
 405         if (getpid() != junk_pid)
 406                 return;
 407         if (junk_git_dir) {
 408                 strbuf_addstr(&sb, junk_git_dir);
 409                 remove_dir_recursively(&sb, 0);
 410                 strbuf_reset(&sb);
 411         }
 412         if (junk_work_tree) {
 413                 strbuf_addstr(&sb, junk_work_tree);
 414                 remove_dir_recursively(&sb, 0);
 415                 strbuf_reset(&sb);
 416         }
 417 }
 418
 419 static void remove_junk_on_signal(int signo)
 420 {
 421         remove_junk();
 422         sigchain_pop(signo);
 423         raise(signo);
 424 }
 425
 426 static struct ref *wanted_peer_refs(const struct ref *refs,
 427                 struct refspec *refspec)
 428 {
 429         struct ref *head = copy_ref(find_ref_by_name(refs, "HEAD"));
 430         struct ref *local_refs = head;
 431         struct ref **tail = head ? &head->next : &local_refs;
 432
 433         if (option_single_branch) {
 434                 struct ref *remote_head = NULL;
 435
 436                 if (!option_branch)
 437                         remote_head = guess_remote_head(head, refs, 0);
 438                 else {
 439                         struct strbuf sb = STRBUF_INIT;
 440                         strbuf_addstr(&sb, src_ref_prefix);
 441                         strbuf_addstr(&sb, option_branch);
 442                         remote_head = find_ref_by_name(refs, sb.buf);
 443                         strbuf_release(&sb);
 444                 }
 445
 446                 if (!remote_head && option_branch)
 447                         warning(_("Could not find remote branch %s to clone."),
 448                                 option_branch);
 449                 else
 450                         get_fetch_map(remote_head, refspec, &tail, 0);
 451         } else
 452                 get_fetch_map(refs, refspec, &tail, 0);
 453
 454         if (!option_mirror && !option_single_branch)
 455                 get_fetch_map(refs, tag_refspec, &tail, 0);
 456
 457         return local_refs;
 458 }
 459
 460 static void write_remote_refs(const struct ref *local_refs)
 461 {
 462         const struct ref *r;
 463
 464         for (r = local_refs; r; r = r->next) {
 465                 if (!r->peer_ref)
 466                         continue;
 467                 add_extra_ref(r->peer_ref->name, r->old_sha1, 0);
 468         }
 469
 470         pack_refs(PACK_REFS_ALL);
 471         clear_extra_refs();
 472 }
 473
 474 static void write_followtags(const struct ref *refs, const char *msg)
 475 {
 476         const struct ref *ref;
 477         for (ref = refs; ref; ref = ref->next) {
 478                 if (prefixcmp(ref->name, "refs/tags/"))
 479                         continue;
 480                 if (!suffixcmp(ref->name, "^{}"))
 481                         continue;
 482                 if (!has_sha1_file(ref->old_sha1))
 483                         continue;
 484                 update_ref(msg, ref->name, ref->old_sha1,
 485                            NULL, 0, DIE_ON_ERR);
 486         }
 487 }
 488
 489 static int write_one_config(const char *key, const char *value, void *data)
 490 {
 491         return git_config_set_multivar(key, value ? value : "true", "^$", 0);
 492 }
 493
 494 static void write_config(struct string_list *config)
 495 {
 496         int i;
 497
 498         for (i = 0; i < config->nr; i++) {
 499                 if (git_config_parse_parameter(config->items[i].string,
 500                                                write_one_config, NULL) < 0)
 501                         die("unable to write parameters to config file");
 502         }
 503 }
 504
 505 int cmd_clone(int argc, const char **argv, const char *prefix)
 506 {
 507         int is_bundle = 0, is_local;
 508         struct stat buf;
 509         const char *repo_name, *repo, *work_tree, *git_dir;
 510         char *path, *dir;
 511         int dest_exists;
 512         const struct ref *refs, *remote_head;
 513         const struct ref *remote_head_points_at;
 514         const struct ref *our_head_points_at;
 515         struct ref *mapped_refs;
 516         struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
 517         struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
 518         struct transport *transport = NULL;
 519         int err = 0;
 520
 521         struct refspec *refspec;
 522         const char *fetch_pattern;
 523
 524         junk_pid = getpid();
 525
 526         packet_trace_identity("clone");
 527         argc = parse_options(argc, argv, prefix, builtin_clone_options,
 528                              builtin_clone_usage, 0);
 529
 530         if (argc > 2)
 531                 usage_msg_opt(_("Too many arguments."),
 532                         builtin_clone_usage, builtin_clone_options);
 533
 534         if (argc == 0)
 535                 usage_msg_opt(_("You must specify a repository to clone."),
 536                         builtin_clone_usage, builtin_clone_options);
 537
 538         if (option_single_branch == -1)
 539                 option_single_branch = option_depth ? 1 : 0;
 540
 541         if (option_mirror)
 542                 option_bare = 1;
 543
 544         if (option_bare) {
 545                 if (option_origin)
 546                         die(_("--bare and --origin %s options are incompatible."),
 547                             option_origin);
 548                 option_no_checkout = 1;
 549         }
 550
 551         if (!option_origin)
 552                 option_origin = "origin";
 553
 554         repo_name = argv[0];
 555
 556         path = get_repo_path(repo_name, &is_bundle);
 557         if (path)
 558                 repo = xstrdup(absolute_path(repo_name));
 559         else if (!strchr(repo_name, ':'))
 560                 die(_("repository '%s' does not exist"), repo_name);
 561         else
 562                 repo = repo_name;
 563         is_local = path && !is_bundle;
 564         if (is_local && option_depth)
 565                 warning(_("--depth is ignored in local clones; use file:// instead."));
 566
 567         if (argc == 2)
 568                 dir = xstrdup(argv[1]);
 569         else
 570                 dir = guess_dir_name(repo_name, is_bundle, option_bare);
 571         strip_trailing_slashes(dir);
 572
 573         dest_exists = !stat(dir, &buf);
 574         if (dest_exists && !is_empty_dir(dir))
 575                 die(_("destination path '%s' already exists and is not "
 576                         "an empty directory."), dir);
 577
 578         strbuf_addf(&reflog_msg, "clone: from %s", repo);
 579
 580         if (option_bare)
 581                 work_tree = NULL;
 582         else {
 583                 work_tree = getenv("GIT_WORK_TREE");
 584                 if (work_tree && !stat(work_tree, &buf))
 585                         die(_("working tree '%s' already exists."), work_tree);
 586         }
 587
 588         if (option_bare || work_tree)
 589                 git_dir = xstrdup(dir);
 590         else {
 591                 work_tree = dir;
 592                 git_dir = xstrdup(mkpath("%s/.git", dir));
 593         }
 594
 595         if (!option_bare) {
 596                 junk_work_tree = work_tree;
 597                 if (safe_create_leading_directories_const(work_tree) < 0)
 598                         die_errno(_("could not create leading directories of '%s'"),
 599                                   work_tree);
 600                 if (!dest_exists && mkdir(work_tree, 0755))
 601                         die_errno(_("could not create work tree dir '%s'."),
 602                                   work_tree);
 603                 set_git_work_tree(work_tree);
 604         }
 605         junk_git_dir = git_dir;
 606         atexit(remove_junk);
 607         sigchain_push_common(remove_junk_on_signal);
 608
 609         setenv(CONFIG_ENVIRONMENT, mkpath("%s/config", git_dir), 1);
 610
 611         if (safe_create_leading_directories_const(git_dir) < 0)
 612                 die(_("could not create leading directories of '%s'"), git_dir);
 613
 614         set_git_dir_init(git_dir, real_git_dir, 0);
 615         if (real_git_dir)
 616                 git_dir = real_git_dir;
 617
 618         if (0 <= option_verbosity) {
 619                 if (option_bare)
 620                         printf(_("Cloning into bare repository '%s'...\n"), dir);
 621                 else
 622                         printf(_("Cloning into '%s'...\n"), dir);
 623         }
 624         init_db(option_template, INIT_DB_QUIET);
 625         write_config(&option_config);
 626
 627         /*
 628          * At this point, the config exists, so we do not need the
 629          * environment variable.  We actually need to unset it, too, to
 630          * re-enable parsing of the global configs.
 631          */
 632         unsetenv(CONFIG_ENVIRONMENT);
 633
 634         git_config(git_default_config, NULL);
 635
 636         if (option_bare) {
 637                 if (option_mirror)
 638                         src_ref_prefix = "refs/";
 639                 strbuf_addstr(&branch_top, src_ref_prefix);
 640
 641                 git_config_set("core.bare", "true");
 642         } else {
 643                 strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
 644         }
 645
 646         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top.buf);
 647
 648         if (option_mirror || !option_bare) {
 649                 /* Configure the remote */
 650                 strbuf_addf(&key, "remote.%s.fetch", option_origin);
 651                 git_config_set_multivar(key.buf, value.buf, "^$", 0);
 652                 strbuf_reset(&key);
 653
 654                 if (option_mirror) {
 655                         strbuf_addf(&key, "remote.%s.mirror", option_origin);
 656                         git_config_set(key.buf, "true");
 657                         strbuf_reset(&key);
 658                 }
 659         }
 660
 661         strbuf_addf(&key, "remote.%s.url", option_origin);
 662         git_config_set(key.buf, repo);
 663         strbuf_reset(&key);
 664
 665         if (option_reference.nr)
 666                 setup_reference();
 667
 668         fetch_pattern = value.buf;
 669         refspec = parse_fetch_refspec(1, &fetch_pattern);
 670
 671         strbuf_reset(&value);
 672
 673         if (is_local) {
 674                 refs = clone_local(path, git_dir);
 675                 mapped_refs = wanted_peer_refs(refs, refspec);
 676         } else {
 677                 struct remote *remote = remote_get(option_origin);
 678                 transport = transport_get(remote, remote->url[0]);
 679
 680                 if (!transport->get_refs_list || !transport->fetch)
 681                         die(_("Don't know how to clone %s"), transport->url);
 682
 683                 transport_set_option(transport, TRANS_OPT_KEEP, "yes");
 684
 685                 if (option_depth)
 686                         transport_set_option(transport, TRANS_OPT_DEPTH,
 687                                              option_depth);
 688                 if (option_single_branch)
 689                         transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
 690
 691                 transport_set_verbosity(transport, option_verbosity, option_progress);
 692
 693                 if (option_upload_pack)
 694                         transport_set_option(transport, TRANS_OPT_UPLOADPACK,
 695                                              option_upload_pack);
 696
 697                 refs = transport_get_remote_refs(transport);
 698                 if (refs) {
 699                         mapped_refs = wanted_peer_refs(refs, refspec);
 700                         transport_fetch_refs(transport, mapped_refs);
 701                 }
 702         }
 703
 704         if (refs) {
 705                 clear_extra_refs();
 706
 707                 write_remote_refs(mapped_refs);
 708                 if (option_single_branch)
 709                         write_followtags(refs, reflog_msg.buf);
 710
 711                 remote_head = find_ref_by_name(refs, "HEAD");
 712                 remote_head_points_at =
 713                         guess_remote_head(remote_head, mapped_refs, 0);
 714
 715                 if (option_branch) {
 716                         struct strbuf head = STRBUF_INIT;
 717                         strbuf_addstr(&head, src_ref_prefix);
 718                         strbuf_addstr(&head, option_branch);
 719                         our_head_points_at =
 720                                 find_ref_by_name(mapped_refs, head.buf);
 721                         strbuf_release(&head);
 722
 723                         if (!our_head_points_at) {
 724                                 warning(_("Remote branch %s not found in "
 725                                         "upstream %s, using HEAD instead"),
 726                                         option_branch, option_origin);
 727                                 our_head_points_at = remote_head_points_at;
 728                         }
 729                 }
 730                 else
 731                         our_head_points_at = remote_head_points_at;
 732         }
 733         else {
 734                 warning(_("You appear to have cloned an empty repository."));
 735                 our_head_points_at = NULL;
 736                 remote_head_points_at = NULL;
 737                 remote_head = NULL;
 738                 option_no_checkout = 1;
 739                 if (!option_bare)
 740                         install_branch_config(0, "master", option_origin,
 741                                               "refs/heads/master");
 742         }
 743
 744         if (remote_head_points_at && !option_bare) {
 745                 struct strbuf head_ref = STRBUF_INIT;
 746                 strbuf_addstr(&head_ref, branch_top.buf);
 747                 strbuf_addstr(&head_ref, "HEAD");
 748                 create_symref(head_ref.buf,
 749                               remote_head_points_at->peer_ref->name,
 750                               reflog_msg.buf);
 751         }
 752
 753         if (our_head_points_at) {
 754                 /* Local default branch link */
 755                 create_symref("HEAD", our_head_points_at->name, NULL);
 756                 if (!option_bare) {
 757                         const char *head = skip_prefix(our_head_points_at->name,
 758                                                        "refs/heads/");
 759                         update_ref(reflog_msg.buf, "HEAD",
 760                                    our_head_points_at->old_sha1,
 761                                    NULL, 0, DIE_ON_ERR);
 762                         install_branch_config(0, head, option_origin,
 763                                               our_head_points_at->name);
 764                 }
 765         } else if (remote_head) {
 766                 /* Source had detached HEAD pointing somewhere. */
 767                 if (!option_bare) {
 768                         update_ref(reflog_msg.buf, "HEAD",
 769                                    remote_head->old_sha1,
 770                                    NULL, REF_NODEREF, DIE_ON_ERR);
 771                         our_head_points_at = remote_head;
 772                 }
 773         } else {
 774                 /* Nothing to checkout out */
 775                 if (!option_no_checkout)
 776                         warning(_("remote HEAD refers to nonexistent ref, "
 777                                 "unable to checkout.\n"));
 778                 option_no_checkout = 1;
 779         }
 780
 781         if (transport) {
 782                 transport_unlock_pack(transport);
 783                 transport_disconnect(transport);
 784         }
 785
 786         if (!option_no_checkout) {
 787                 struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
 788                 struct unpack_trees_options opts;
 789                 struct tree *tree;
 790                 struct tree_desc t;
 791                 int fd;
 792
 793                 /* We need to be in the new work tree for the checkout */
 794                 setup_work_tree();
 795
 796                 fd = hold_locked_index(lock_file, 1);
 797
 798                 memset(&opts, 0, sizeof opts);
 799                 opts.update = 1;
 800                 opts.merge = 1;
 801                 opts.fn = oneway_merge;
 802                 opts.verbose_update = (option_verbosity > 0);
 803                 opts.src_index = &the_index;
 804                 opts.dst_index = &the_index;
 805
 806                 tree = parse_tree_indirect(our_head_points_at->old_sha1);
 807                 parse_tree(tree);
 808                 init_tree_desc(&t, tree->buffer, tree->size);
 809                 unpack_trees(1, &t, &opts);
 810
 811                 if (write_cache(fd, active_cache, active_nr) ||
 812                     commit_locked_index(lock_file))
 813                         die(_("unable to write new index file"));
 814
 815                 err |= run_hook(NULL, "post-checkout", sha1_to_hex(null_sha1),
 816                                 sha1_to_hex(our_head_points_at->old_sha1), "1",
 817                                 NULL);
 818
 819                 if (!err && option_recursive)
 820                         err = run_command_v_opt(argv_submodule, RUN_GIT_CMD);
 821         }
 822
 823         strbuf_release(&reflog_msg);
 824         strbuf_release(&branch_top);
 825         strbuf_release(&key);
 826         strbuf_release(&value);
 827         junk_pid = 0;
 828         return err;
 829 }