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 #define USE_THE_INDEX_COMPATIBILITY_MACROS
  12 #include "builtin.h"
  13 #include "config.h"
  14 #include "lockfile.h"
  15 #include "parse-options.h"
  16 #include "fetch-pack.h"
  17 #include "refs.h"
  18 #include "refspec.h"
  19 #include "object-store.h"
  20 #include "tree.h"
  21 #include "tree-walk.h"
  22 #include "unpack-trees.h"
  23 #include "transport.h"
  24 #include "strbuf.h"
  25 #include "dir.h"
  26 #include "dir-iterator.h"
  27 #include "iterator.h"
  28 #include "sigchain.h"
  29 #include "branch.h"
  30 #include "remote.h"
  31 #include "run-command.h"
  32 #include "connected.h"
  33 #include "packfile.h"
  34 #include "list-objects-filter-options.h"
  35 #include "hook.h"
  36 #include "bundle.h"
  37
  38 /*
  39  * Overall FIXMEs:
  40  *  - respect DB_ENVIRONMENT for .git/objects.
  41  *
  42  * Implementation notes:
  43  *  - dropping use-separate-remote and no-separate-remote compatibility
  44  *
  45  */
  46 static const char * const builtin_clone_usage[] = {
  47         N_("git clone [<options>] [--] <repo> [<dir>]"),
  48         NULL
  49 };
  50
  51 static int option_no_checkout, option_bare, option_mirror, option_single_branch = -1;
  52 static int option_local = -1, option_no_hardlinks, option_shared;
  53 static int option_no_tags;
  54 static int option_shallow_submodules;
  55 static int option_reject_shallow = -1;    /* unspecified */
  56 static int config_reject_shallow = -1;    /* unspecified */
  57 static int deepen;
  58 static char *option_template, *option_depth, *option_since;
  59 static char *option_origin = NULL;
  60 static char *remote_name = NULL;
  61 static char *option_branch = NULL;
  62 static struct string_list option_not = STRING_LIST_INIT_NODUP;
  63 static const char *real_git_dir;
  64 static char *option_upload_pack = "git-upload-pack";
  65 static int option_verbosity;
  66 static int option_progress = -1;
  67 static int option_sparse_checkout;
  68 static enum transport_family family;
  69 static struct string_list option_config = STRING_LIST_INIT_NODUP;
  70 static struct string_list option_required_reference = STRING_LIST_INIT_NODUP;
  71 static struct string_list option_optional_reference = STRING_LIST_INIT_NODUP;
  72 static int option_dissociate;
  73 static int max_jobs = -1;
  74 static struct string_list option_recurse_submodules = STRING_LIST_INIT_NODUP;
  75 static struct list_objects_filter_options filter_options;
  76 static int option_filter_submodules = -1;    /* unspecified */
  77 static int config_filter_submodules = -1;    /* unspecified */
  78 static struct string_list server_options = STRING_LIST_INIT_NODUP;
  79 static int option_remote_submodules;
  80
  81 static int recurse_submodules_cb(const struct option *opt,
  82                                  const char *arg, int unset)
  83 {
  84         if (unset)
  85                 string_list_clear((struct string_list *)opt->value, 0);
  86         else if (arg)
  87                 string_list_append((struct string_list *)opt->value, arg);
  88         else
  89                 string_list_append((struct string_list *)opt->value,
  90                                    (const char *)opt->defval);
  91
  92         return 0;
  93 }
  94
  95 static struct option builtin_clone_options[] = {
  96         OPT__VERBOSITY(&option_verbosity),
  97         OPT_BOOL(0, "progress", &option_progress,
  98                  N_("force progress reporting")),
  99         OPT_BOOL(0, "reject-shallow", &option_reject_shallow,
 100                  N_("don't clone shallow repository")),
 101         OPT_BOOL('n', "no-checkout", &option_no_checkout,
 102                  N_("don't create a checkout")),
 103         OPT_BOOL(0, "bare", &option_bare, N_("create a bare repository")),
 104         OPT_HIDDEN_BOOL(0, "naked", &option_bare,
 105                         N_("create a bare repository")),
 106         OPT_BOOL(0, "mirror", &option_mirror,
 107                  N_("create a mirror repository (implies bare)")),
 108         OPT_BOOL('l', "local", &option_local,
 109                 N_("to clone from a local repository")),
 110         OPT_BOOL(0, "no-hardlinks", &option_no_hardlinks,
 111                     N_("don't use local hardlinks, always copy")),
 112         OPT_BOOL('s', "shared", &option_shared,
 113                     N_("setup as shared repository")),
 114         { OPTION_CALLBACK, 0, "recurse-submodules", &option_recurse_submodules,
 115           N_("pathspec"), N_("initialize submodules in the clone"),
 116           PARSE_OPT_OPTARG, recurse_submodules_cb, (intptr_t)"." },
 117         OPT_ALIAS(0, "recursive", "recurse-submodules"),
 118         OPT_INTEGER('j', "jobs", &max_jobs,
 119                     N_("number of submodules cloned in parallel")),
 120         OPT_STRING(0, "template", &option_template, N_("template-directory"),
 121                    N_("directory from which templates will be used")),
 122         OPT_STRING_LIST(0, "reference", &option_required_reference, N_("repo"),
 123                         N_("reference repository")),
 124         OPT_STRING_LIST(0, "reference-if-able", &option_optional_reference,
 125                         N_("repo"), N_("reference repository")),
 126         OPT_BOOL(0, "dissociate", &option_dissociate,
 127                  N_("use --reference only while cloning")),
 128         OPT_STRING('o', "origin", &option_origin, N_("name"),
 129                    N_("use <name> instead of 'origin' to track upstream")),
 130         OPT_STRING('b', "branch", &option_branch, N_("branch"),
 131                    N_("checkout <branch> instead of the remote's HEAD")),
 132         OPT_STRING('u', "upload-pack", &option_upload_pack, N_("path"),
 133                    N_("path to git-upload-pack on the remote")),
 134         OPT_STRING(0, "depth", &option_depth, N_("depth"),
 135                     N_("create a shallow clone of that depth")),
 136         OPT_STRING(0, "shallow-since", &option_since, N_("time"),
 137                     N_("create a shallow clone since a specific time")),
 138         OPT_STRING_LIST(0, "shallow-exclude", &option_not, N_("revision"),
 139                         N_("deepen history of shallow clone, excluding rev")),
 140         OPT_BOOL(0, "single-branch", &option_single_branch,
 141                     N_("clone only one branch, HEAD or --branch")),
 142         OPT_BOOL(0, "no-tags", &option_no_tags,
 143                  N_("don't clone any tags, and make later fetches not to follow them")),
 144         OPT_BOOL(0, "shallow-submodules", &option_shallow_submodules,
 145                     N_("any cloned submodules will be shallow")),
 146         OPT_STRING(0, "separate-git-dir", &real_git_dir, N_("gitdir"),
 147                    N_("separate git dir from working tree")),
 148         OPT_STRING_LIST('c', "config", &option_config, N_("key=value"),
 149                         N_("set config inside the new repository")),
 150         OPT_STRING_LIST(0, "server-option", &server_options,
 151                         N_("server-specific"), N_("option to transmit")),
 152         OPT_SET_INT('4', "ipv4", &family, N_("use IPv4 addresses only"),
 153                         TRANSPORT_FAMILY_IPV4),
 154         OPT_SET_INT('6', "ipv6", &family, N_("use IPv6 addresses only"),
 155                         TRANSPORT_FAMILY_IPV6),
 156         OPT_PARSE_LIST_OBJECTS_FILTER(&filter_options),
 157         OPT_BOOL(0, "also-filter-submodules", &option_filter_submodules,
 158                     N_("apply partial clone filters to submodules")),
 159         OPT_BOOL(0, "remote-submodules", &option_remote_submodules,
 160                     N_("any cloned submodules will use their remote-tracking branch")),
 161         OPT_BOOL(0, "sparse", &option_sparse_checkout,
 162                     N_("initialize sparse-checkout file to include only files at root")),
 163         OPT_END()
 164 };
 165
 166 static const char *get_repo_path_1(struct strbuf *path, int *is_bundle)
 167 {
 168         static char *suffix[] = { "/.git", "", ".git/.git", ".git" };
 169         static char *bundle_suffix[] = { ".bundle", "" };
 170         size_t baselen = path->len;
 171         struct stat st;
 172         int i;
 173
 174         for (i = 0; i < ARRAY_SIZE(suffix); i++) {
 175                 strbuf_setlen(path, baselen);
 176                 strbuf_addstr(path, suffix[i]);
 177                 if (stat(path->buf, &st))
 178                         continue;
 179                 if (S_ISDIR(st.st_mode) && is_git_directory(path->buf)) {
 180                         *is_bundle = 0;
 181                         return path->buf;
 182                 } else if (S_ISREG(st.st_mode) && st.st_size > 8) {
 183                         /* Is it a "gitfile"? */
 184                         char signature[8];
 185                         const char *dst;
 186                         int len, fd = open(path->buf, O_RDONLY);
 187                         if (fd < 0)
 188                                 continue;
 189                         len = read_in_full(fd, signature, 8);
 190                         close(fd);
 191                         if (len != 8 || strncmp(signature, "gitdir: ", 8))
 192                                 continue;
 193                         dst = read_gitfile(path->buf);
 194                         if (dst) {
 195                                 *is_bundle = 0;
 196                                 return dst;
 197                         }
 198                 }
 199         }
 200
 201         for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
 202                 strbuf_setlen(path, baselen);
 203                 strbuf_addstr(path, bundle_suffix[i]);
 204                 if (!stat(path->buf, &st) && S_ISREG(st.st_mode)) {
 205                         *is_bundle = 1;
 206                         return path->buf;
 207                 }
 208         }
 209
 210         return NULL;
 211 }
 212
 213 static char *get_repo_path(const char *repo, int *is_bundle)
 214 {
 215         struct strbuf path = STRBUF_INIT;
 216         const char *raw;
 217         char *canon;
 218
 219         strbuf_addstr(&path, repo);
 220         raw = get_repo_path_1(&path, is_bundle);
 221         canon = raw ? absolute_pathdup(raw) : NULL;
 222         strbuf_release(&path);
 223         return canon;
 224 }
 225
 226 static int add_one_reference(struct string_list_item *item, void *cb_data)
 227 {
 228         struct strbuf err = STRBUF_INIT;
 229         int *required = cb_data;
 230         char *ref_git = compute_alternate_path(item->string, &err);
 231
 232         if (!ref_git) {
 233                 if (*required)
 234                         die("%s", err.buf);
 235                 else
 236                         fprintf(stderr,
 237                                 _("info: Could not add alternate for '%s': %s\n"),
 238                                 item->string, err.buf);
 239         } else {
 240                 struct strbuf sb = STRBUF_INIT;
 241                 strbuf_addf(&sb, "%s/objects", ref_git);
 242                 add_to_alternates_file(sb.buf);
 243                 strbuf_release(&sb);
 244         }
 245
 246         strbuf_release(&err);
 247         free(ref_git);
 248         return 0;
 249 }
 250
 251 static void setup_reference(void)
 252 {
 253         int required = 1;
 254         for_each_string_list(&option_required_reference,
 255                              add_one_reference, &required);
 256         required = 0;
 257         for_each_string_list(&option_optional_reference,
 258                              add_one_reference, &required);
 259 }
 260
 261 static void copy_alternates(struct strbuf *src, const char *src_repo)
 262 {
 263         /*
 264          * Read from the source objects/info/alternates file
 265          * and copy the entries to corresponding file in the
 266          * destination repository with add_to_alternates_file().
 267          * Both src and dst have "$path/objects/info/alternates".
 268          *
 269          * Instead of copying bit-for-bit from the original,
 270          * we need to append to existing one so that the already
 271          * created entry via "clone -s" is not lost, and also
 272          * to turn entries with paths relative to the original
 273          * absolute, so that they can be used in the new repository.
 274          */
 275         FILE *in = xfopen(src->buf, "r");
 276         struct strbuf line = STRBUF_INIT;
 277
 278         while (strbuf_getline(&line, in) != EOF) {
 279                 char *abs_path;
 280                 if (!line.len || line.buf[0] == '#')
 281                         continue;
 282                 if (is_absolute_path(line.buf)) {
 283                         add_to_alternates_file(line.buf);
 284                         continue;
 285                 }
 286                 abs_path = mkpathdup("%s/objects/%s", src_repo, line.buf);
 287                 if (!normalize_path_copy(abs_path, abs_path))
 288                         add_to_alternates_file(abs_path);
 289                 else
 290                         warning("skipping invalid relative alternate: %s/%s",
 291                                 src_repo, line.buf);
 292                 free(abs_path);
 293         }
 294         strbuf_release(&line);
 295         fclose(in);
 296 }
 297
 298 static void mkdir_if_missing(const char *pathname, mode_t mode)
 299 {
 300         struct stat st;
 301
 302         if (!mkdir(pathname, mode))
 303                 return;
 304
 305         if (errno != EEXIST)
 306                 die_errno(_("failed to create directory '%s'"), pathname);
 307         else if (stat(pathname, &st))
 308                 die_errno(_("failed to stat '%s'"), pathname);
 309         else if (!S_ISDIR(st.st_mode))
 310                 die(_("%s exists and is not a directory"), pathname);
 311 }
 312
 313 static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
 314                                    const char *src_repo)
 315 {
 316         int src_len, dest_len;
 317         struct dir_iterator *iter;
 318         int iter_status;
 319         unsigned int flags;
 320         struct strbuf realpath = STRBUF_INIT;
 321
 322         mkdir_if_missing(dest->buf, 0777);
 323
 324         flags = DIR_ITERATOR_PEDANTIC | DIR_ITERATOR_FOLLOW_SYMLINKS;
 325         iter = dir_iterator_begin(src->buf, flags);
 326
 327         if (!iter)
 328                 die_errno(_("failed to start iterator over '%s'"), src->buf);
 329
 330         strbuf_addch(src, '/');
 331         src_len = src->len;
 332         strbuf_addch(dest, '/');
 333         dest_len = dest->len;
 334
 335         while ((iter_status = dir_iterator_advance(iter)) == ITER_OK) {
 336                 strbuf_setlen(src, src_len);
 337                 strbuf_addstr(src, iter->relative_path);
 338                 strbuf_setlen(dest, dest_len);
 339                 strbuf_addstr(dest, iter->relative_path);
 340
 341                 if (S_ISDIR(iter->st.st_mode)) {
 342                         mkdir_if_missing(dest->buf, 0777);
 343                         continue;
 344                 }
 345
 346                 /* Files that cannot be copied bit-for-bit... */
 347                 if (!fspathcmp(iter->relative_path, "info/alternates")) {
 348                         copy_alternates(src, 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                         strbuf_realpath(&realpath, src->buf, 1);
 356                         if (!link(realpath.buf, dest->buf))
 357                                 continue;
 358                         if (option_local > 0)
 359                                 die_errno(_("failed to create link '%s'"), dest->buf);
 360                         option_no_hardlinks = 1;
 361                 }
 362                 if (copy_file_with_time(dest->buf, src->buf, 0666))
 363                         die_errno(_("failed to copy file to '%s'"), dest->buf);
 364         }
 365
 366         if (iter_status != ITER_DONE) {
 367                 strbuf_setlen(src, src_len);
 368                 die(_("failed to iterate over '%s'"), src->buf);
 369         }
 370
 371         strbuf_release(&realpath);
 372 }
 373
 374 static void clone_local(const char *src_repo, const char *dest_repo)
 375 {
 376         if (option_shared) {
 377                 struct strbuf alt = STRBUF_INIT;
 378                 get_common_dir(&alt, src_repo);
 379                 strbuf_addstr(&alt, "/objects");
 380                 add_to_alternates_file(alt.buf);
 381                 strbuf_release(&alt);
 382         } else {
 383                 struct strbuf src = STRBUF_INIT;
 384                 struct strbuf dest = STRBUF_INIT;
 385                 get_common_dir(&src, src_repo);
 386                 get_common_dir(&dest, dest_repo);
 387                 strbuf_addstr(&src, "/objects");
 388                 strbuf_addstr(&dest, "/objects");
 389                 copy_or_link_directory(&src, &dest, src_repo);
 390                 strbuf_release(&src);
 391                 strbuf_release(&dest);
 392         }
 393
 394         if (0 <= option_verbosity)
 395                 fprintf(stderr, _("done.\n"));
 396 }
 397
 398 static const char *junk_work_tree;
 399 static int junk_work_tree_flags;
 400 static const char *junk_git_dir;
 401 static int junk_git_dir_flags;
 402 static enum {
 403         JUNK_LEAVE_NONE,
 404         JUNK_LEAVE_REPO,
 405         JUNK_LEAVE_ALL
 406 } junk_mode = JUNK_LEAVE_NONE;
 407
 408 static const char junk_leave_repo_msg[] =
 409 N_("Clone succeeded, but checkout failed.\n"
 410    "You can inspect what was checked out with 'git status'\n"
 411    "and retry with 'git restore --source=HEAD :/'\n");
 412
 413 static void remove_junk(void)
 414 {
 415         struct strbuf sb = STRBUF_INIT;
 416
 417         switch (junk_mode) {
 418         case JUNK_LEAVE_REPO:
 419                 warning("%s", _(junk_leave_repo_msg));
 420                 /* fall-through */
 421         case JUNK_LEAVE_ALL:
 422                 return;
 423         default:
 424                 /* proceed to removal */
 425                 break;
 426         }
 427
 428         if (junk_git_dir) {
 429                 strbuf_addstr(&sb, junk_git_dir);
 430                 remove_dir_recursively(&sb, junk_git_dir_flags);
 431                 strbuf_reset(&sb);
 432         }
 433         if (junk_work_tree) {
 434                 strbuf_addstr(&sb, junk_work_tree);
 435                 remove_dir_recursively(&sb, junk_work_tree_flags);
 436         }
 437         strbuf_release(&sb);
 438 }
 439
 440 static void remove_junk_on_signal(int signo)
 441 {
 442         remove_junk();
 443         sigchain_pop(signo);
 444         raise(signo);
 445 }
 446
 447 static struct ref *find_remote_branch(const struct ref *refs, const char *branch)
 448 {
 449         struct ref *ref;
 450         struct strbuf head = STRBUF_INIT;
 451         strbuf_addstr(&head, "refs/heads/");
 452         strbuf_addstr(&head, branch);
 453         ref = find_ref_by_name(refs, head.buf);
 454         strbuf_release(&head);
 455
 456         if (ref)
 457                 return ref;
 458
 459         strbuf_addstr(&head, "refs/tags/");
 460         strbuf_addstr(&head, branch);
 461         ref = find_ref_by_name(refs, head.buf);
 462         strbuf_release(&head);
 463
 464         return ref;
 465 }
 466
 467 static struct ref *wanted_peer_refs(const struct ref *refs,
 468                 struct refspec *refspec)
 469 {
 470         struct ref *head = copy_ref(find_ref_by_name(refs, "HEAD"));
 471         struct ref *local_refs = head;
 472         struct ref **tail = head ? &head->next : &local_refs;
 473
 474         if (option_single_branch) {
 475                 struct ref *remote_head = NULL;
 476
 477                 if (!option_branch)
 478                         remote_head = guess_remote_head(head, refs, 0);
 479                 else {
 480                         local_refs = NULL;
 481                         tail = &local_refs;
 482                         remote_head = copy_ref(find_remote_branch(refs, option_branch));
 483                 }
 484
 485                 if (!remote_head && option_branch)
 486                         warning(_("Could not find remote branch %s to clone."),
 487                                 option_branch);
 488                 else {
 489                         int i;
 490                         for (i = 0; i < refspec->nr; i++)
 491                                 get_fetch_map(remote_head, &refspec->items[i],
 492                                               &tail, 0);
 493
 494                         /* if --branch=tag, pull the requested tag explicitly */
 495                         get_fetch_map(remote_head, tag_refspec, &tail, 0);
 496                 }
 497         } else {
 498                 int i;
 499                 for (i = 0; i < refspec->nr; i++)
 500                         get_fetch_map(refs, &refspec->items[i], &tail, 0);
 501         }
 502
 503         if (!option_mirror && !option_single_branch && !option_no_tags)
 504                 get_fetch_map(refs, tag_refspec, &tail, 0);
 505
 506         return local_refs;
 507 }
 508
 509 static void write_remote_refs(const struct ref *local_refs)
 510 {
 511         const struct ref *r;
 512
 513         struct ref_transaction *t;
 514         struct strbuf err = STRBUF_INIT;
 515
 516         t = ref_transaction_begin(&err);
 517         if (!t)
 518                 die("%s", err.buf);
 519
 520         for (r = local_refs; r; r = r->next) {
 521                 if (!r->peer_ref)
 522                         continue;
 523                 if (ref_transaction_create(t, r->peer_ref->name, &r->old_oid,
 524                                            0, NULL, &err))
 525                         die("%s", err.buf);
 526         }
 527
 528         if (initial_ref_transaction_commit(t, &err))
 529                 die("%s", err.buf);
 530
 531         strbuf_release(&err);
 532         ref_transaction_free(t);
 533 }
 534
 535 static void write_followtags(const struct ref *refs, const char *msg)
 536 {
 537         const struct ref *ref;
 538         for (ref = refs; ref; ref = ref->next) {
 539                 if (!starts_with(ref->name, "refs/tags/"))
 540                         continue;
 541                 if (ends_with(ref->name, "^{}"))
 542                         continue;
 543                 if (!has_object_file_with_flags(&ref->old_oid,
 544                                                 OBJECT_INFO_QUICK |
 545                                                 OBJECT_INFO_SKIP_FETCH_OBJECT))
 546                         continue;
 547                 update_ref(msg, ref->name, &ref->old_oid, NULL, 0,
 548                            UPDATE_REFS_DIE_ON_ERR);
 549         }
 550 }
 551
 552 static const struct object_id *iterate_ref_map(void *cb_data)
 553 {
 554         struct ref **rm = cb_data;
 555         struct ref *ref = *rm;
 556
 557         /*
 558          * Skip anything missing a peer_ref, which we are not
 559          * actually going to write a ref for.
 560          */
 561         while (ref && !ref->peer_ref)
 562                 ref = ref->next;
 563         if (!ref)
 564                 return NULL;
 565
 566         *rm = ref->next;
 567         return &ref->old_oid;
 568 }
 569
 570 static void update_remote_refs(const struct ref *refs,
 571                                const struct ref *mapped_refs,
 572                                const struct ref *remote_head_points_at,
 573                                const char *branch_top,
 574                                const char *msg,
 575                                struct transport *transport,
 576                                int check_connectivity)
 577 {
 578         const struct ref *rm = mapped_refs;
 579
 580         if (check_connectivity) {
 581                 struct check_connected_options opt = CHECK_CONNECTED_INIT;
 582
 583                 opt.transport = transport;
 584                 opt.progress = transport->progress;
 585
 586                 if (check_connected(iterate_ref_map, &rm, &opt))
 587                         die(_("remote did not send all necessary objects"));
 588         }
 589
 590         if (refs) {
 591                 write_remote_refs(mapped_refs);
 592                 if (option_single_branch && !option_no_tags)
 593                         write_followtags(refs, msg);
 594         }
 595
 596         if (remote_head_points_at && !option_bare) {
 597                 struct strbuf head_ref = STRBUF_INIT;
 598                 strbuf_addstr(&head_ref, branch_top);
 599                 strbuf_addstr(&head_ref, "HEAD");
 600                 if (create_symref(head_ref.buf,
 601                                   remote_head_points_at->peer_ref->name,
 602                                   msg) < 0)
 603                         die(_("unable to update %s"), head_ref.buf);
 604                 strbuf_release(&head_ref);
 605         }
 606 }
 607
 608 static void update_head(const struct ref *our, const struct ref *remote,
 609                         const char *unborn, const char *msg)
 610 {
 611         const char *head;
 612         if (our && skip_prefix(our->name, "refs/heads/", &head)) {
 613                 /* Local default branch link */
 614                 if (create_symref("HEAD", our->name, NULL) < 0)
 615                         die(_("unable to update HEAD"));
 616                 if (!option_bare) {
 617                         update_ref(msg, "HEAD", &our->old_oid, NULL, 0,
 618                                    UPDATE_REFS_DIE_ON_ERR);
 619                         install_branch_config(0, head, remote_name, our->name);
 620                 }
 621         } else if (our) {
 622                 struct commit *c = lookup_commit_reference(the_repository,
 623                                                            &our->old_oid);
 624                 /* --branch specifies a non-branch (i.e. tags), detach HEAD */
 625                 update_ref(msg, "HEAD", &c->object.oid, NULL, REF_NO_DEREF,
 626                            UPDATE_REFS_DIE_ON_ERR);
 627         } else if (remote) {
 628                 /*
 629                  * We know remote HEAD points to a non-branch, or
 630                  * HEAD points to a branch but we don't know which one.
 631                  * Detach HEAD in all these cases.
 632                  */
 633                 update_ref(msg, "HEAD", &remote->old_oid, NULL, REF_NO_DEREF,
 634                            UPDATE_REFS_DIE_ON_ERR);
 635         } else if (unborn && skip_prefix(unborn, "refs/heads/", &head)) {
 636                 /*
 637                  * Unborn head from remote; same as "our" case above except
 638                  * that we have no ref to update.
 639                  */
 640                 if (create_symref("HEAD", unborn, NULL) < 0)
 641                         die(_("unable to update HEAD"));
 642                 if (!option_bare)
 643                         install_branch_config(0, head, remote_name, unborn);
 644         }
 645 }
 646
 647 static int git_sparse_checkout_init(const char *repo)
 648 {
 649         struct strvec argv = STRVEC_INIT;
 650         int result = 0;
 651         strvec_pushl(&argv, "-C", repo, "sparse-checkout", "set", NULL);
 652
 653         /*
 654          * We must apply the setting in the current process
 655          * for the later checkout to use the sparse-checkout file.
 656          */
 657         core_apply_sparse_checkout = 1;
 658
 659         if (run_command_v_opt(argv.v, RUN_GIT_CMD)) {
 660                 error(_("failed to initialize sparse-checkout"));
 661                 result = 1;
 662         }
 663
 664         strvec_clear(&argv);
 665         return result;
 666 }
 667
 668 static int checkout(int submodule_progress, int filter_submodules)
 669 {
 670         struct object_id oid;
 671         char *head;
 672         struct lock_file lock_file = LOCK_INIT;
 673         struct unpack_trees_options opts;
 674         struct tree *tree;
 675         struct tree_desc t;
 676         int err = 0;
 677
 678         if (option_no_checkout)
 679                 return 0;
 680
 681         head = resolve_refdup("HEAD", RESOLVE_REF_READING, &oid, NULL);
 682         if (!head) {
 683                 warning(_("remote HEAD refers to nonexistent ref, "
 684                           "unable to checkout"));
 685                 return 0;
 686         }
 687         if (!strcmp(head, "HEAD")) {
 688                 if (advice_enabled(ADVICE_DETACHED_HEAD))
 689                         detach_advice(oid_to_hex(&oid));
 690                 FREE_AND_NULL(head);
 691         } else {
 692                 if (!starts_with(head, "refs/heads/"))
 693                         die(_("HEAD not found below refs/heads!"));
 694         }
 695
 696         /* We need to be in the new work tree for the checkout */
 697         setup_work_tree();
 698
 699         hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
 700
 701         memset(&opts, 0, sizeof opts);
 702         opts.update = 1;
 703         opts.merge = 1;
 704         opts.clone = 1;
 705         opts.preserve_ignored = 0;
 706         opts.fn = oneway_merge;
 707         opts.verbose_update = (option_verbosity >= 0);
 708         opts.src_index = &the_index;
 709         opts.dst_index = &the_index;
 710         init_checkout_metadata(&opts.meta, head, &oid, NULL);
 711
 712         tree = parse_tree_indirect(&oid);
 713         if (!tree)
 714                 die(_("unable to parse commit %s"), oid_to_hex(&oid));
 715         parse_tree(tree);
 716         init_tree_desc(&t, tree->buffer, tree->size);
 717         if (unpack_trees(1, &t, &opts) < 0)
 718                 die(_("unable to checkout working tree"));
 719
 720         free(head);
 721
 722         if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
 723                 die(_("unable to write new index file"));
 724
 725         err |= run_hooks_l("post-checkout", oid_to_hex(null_oid()),
 726                            oid_to_hex(&oid), "1", NULL);
 727
 728         if (!err && (option_recurse_submodules.nr > 0)) {
 729                 struct strvec args = STRVEC_INIT;
 730                 strvec_pushl(&args, "submodule", "update", "--require-init", "--recursive", NULL);
 731
 732                 if (option_shallow_submodules == 1)
 733                         strvec_push(&args, "--depth=1");
 734
 735                 if (max_jobs != -1)
 736                         strvec_pushf(&args, "--jobs=%d", max_jobs);
 737
 738                 if (submodule_progress)
 739                         strvec_push(&args, "--progress");
 740
 741                 if (option_verbosity < 0)
 742                         strvec_push(&args, "--quiet");
 743
 744                 if (option_remote_submodules) {
 745                         strvec_push(&args, "--remote");
 746                         strvec_push(&args, "--no-fetch");
 747                 }
 748
 749                 if (filter_submodules && filter_options.choice)
 750                         strvec_pushf(&args, "--filter=%s",
 751                                      expand_list_objects_filter_spec(&filter_options));
 752
 753                 if (option_single_branch >= 0)
 754                         strvec_push(&args, option_single_branch ?
 755                                                "--single-branch" :
 756                                                "--no-single-branch");
 757
 758                 err = run_command_v_opt(args.v, RUN_GIT_CMD);
 759                 strvec_clear(&args);
 760         }
 761
 762         return err;
 763 }
 764
 765 static int git_clone_config(const char *k, const char *v, void *cb)
 766 {
 767         if (!strcmp(k, "clone.defaultremotename")) {
 768                 free(remote_name);
 769                 remote_name = xstrdup(v);
 770         }
 771         if (!strcmp(k, "clone.rejectshallow"))
 772                 config_reject_shallow = git_config_bool(k, v);
 773         if (!strcmp(k, "clone.filtersubmodules"))
 774                 config_filter_submodules = git_config_bool(k, v);
 775
 776         return git_default_config(k, v, cb);
 777 }
 778
 779 static int write_one_config(const char *key, const char *value, void *data)
 780 {
 781         /*
 782          * give git_clone_config a chance to write config values back to the
 783          * environment, since git_config_set_multivar_gently only deals with
 784          * config-file writes
 785          */
 786         int apply_failed = git_clone_config(key, value, data);
 787         if (apply_failed)
 788                 return apply_failed;
 789
 790         return git_config_set_multivar_gently(key,
 791                                               value ? value : "true",
 792                                               CONFIG_REGEX_NONE, 0);
 793 }
 794
 795 static void write_config(struct string_list *config)
 796 {
 797         int i;
 798
 799         for (i = 0; i < config->nr; i++) {
 800                 if (git_config_parse_parameter(config->items[i].string,
 801                                                write_one_config, NULL) < 0)
 802                         die(_("unable to write parameters to config file"));
 803         }
 804 }
 805
 806 static void write_refspec_config(const char *src_ref_prefix,
 807                 const struct ref *our_head_points_at,
 808                 const struct ref *remote_head_points_at,
 809                 struct strbuf *branch_top)
 810 {
 811         struct strbuf key = STRBUF_INIT;
 812         struct strbuf value = STRBUF_INIT;
 813
 814         if (option_mirror || !option_bare) {
 815                 if (option_single_branch && !option_mirror) {
 816                         if (option_branch) {
 817                                 if (starts_with(our_head_points_at->name, "refs/tags/"))
 818                                         strbuf_addf(&value, "+%s:%s", our_head_points_at->name,
 819                                                 our_head_points_at->name);
 820                                 else
 821                                         strbuf_addf(&value, "+%s:%s%s", our_head_points_at->name,
 822                                                 branch_top->buf, option_branch);
 823                         } else if (remote_head_points_at) {
 824                                 const char *head = remote_head_points_at->name;
 825                                 if (!skip_prefix(head, "refs/heads/", &head))
 826                                         BUG("remote HEAD points at non-head?");
 827
 828                                 strbuf_addf(&value, "+%s:%s%s", remote_head_points_at->name,
 829                                                 branch_top->buf, head);
 830                         }
 831                         /*
 832                          * otherwise, the next "git fetch" will
 833                          * simply fetch from HEAD without updating
 834                          * any remote-tracking branch, which is what
 835                          * we want.
 836                          */
 837                 } else {
 838                         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top->buf);
 839                 }
 840                 /* Configure the remote */
 841                 if (value.len) {
 842                         strbuf_addf(&key, "remote.%s.fetch", remote_name);
 843                         git_config_set_multivar(key.buf, value.buf, "^$", 0);
 844                         strbuf_reset(&key);
 845
 846                         if (option_mirror) {
 847                                 strbuf_addf(&key, "remote.%s.mirror", remote_name);
 848                                 git_config_set(key.buf, "true");
 849                                 strbuf_reset(&key);
 850                         }
 851                 }
 852         }
 853
 854         strbuf_release(&key);
 855         strbuf_release(&value);
 856 }
 857
 858 static void dissociate_from_references(void)
 859 {
 860         static const char* argv[] = { "repack", "-a", "-d", NULL };
 861         char *alternates = git_pathdup("objects/info/alternates");
 862
 863         if (!access(alternates, F_OK)) {
 864                 if (run_command_v_opt(argv, RUN_GIT_CMD|RUN_COMMAND_NO_STDIN))
 865                         die(_("cannot repack to clean up"));
 866                 if (unlink(alternates) && errno != ENOENT)
 867                         die_errno(_("cannot unlink temporary alternates file"));
 868         }
 869         free(alternates);
 870 }
 871
 872 static int path_exists(const char *path)
 873 {
 874         struct stat sb;
 875         return !stat(path, &sb);
 876 }
 877
 878 int cmd_clone(int argc, const char **argv, const char *prefix)
 879 {
 880         int is_bundle = 0, is_local;
 881         int reject_shallow = 0;
 882         const char *repo_name, *repo, *work_tree, *git_dir;
 883         char *path = NULL, *dir, *display_repo = NULL;
 884         int dest_exists, real_dest_exists = 0;
 885         const struct ref *refs, *remote_head;
 886         struct ref *remote_head_points_at = NULL;
 887         const struct ref *our_head_points_at;
 888         char *unborn_head = NULL;
 889         struct ref *mapped_refs = NULL;
 890         const struct ref *ref;
 891         struct strbuf key = STRBUF_INIT;
 892         struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
 893         struct transport *transport = NULL;
 894         const char *src_ref_prefix = "refs/heads/";
 895         struct remote *remote;
 896         int err = 0, complete_refs_before_fetch = 1;
 897         int submodule_progress;
 898         int filter_submodules = 0;
 899
 900         struct transport_ls_refs_options transport_ls_refs_options =
 901                 TRANSPORT_LS_REFS_OPTIONS_INIT;
 902
 903         packet_trace_identity("clone");
 904
 905         git_config(git_clone_config, NULL);
 906
 907         argc = parse_options(argc, argv, prefix, builtin_clone_options,
 908                              builtin_clone_usage, 0);
 909
 910         if (argc > 2)
 911                 usage_msg_opt(_("Too many arguments."),
 912                         builtin_clone_usage, builtin_clone_options);
 913
 914         if (argc == 0)
 915                 usage_msg_opt(_("You must specify a repository to clone."),
 916                         builtin_clone_usage, builtin_clone_options);
 917
 918         if (option_depth || option_since || option_not.nr)
 919                 deepen = 1;
 920         if (option_single_branch == -1)
 921                 option_single_branch = deepen ? 1 : 0;
 922
 923         if (option_mirror)
 924                 option_bare = 1;
 925
 926         if (option_bare) {
 927                 if (option_origin)
 928                         die(_("options '%s' and '%s %s' cannot be used together"),
 929                             "--bare", "--origin", option_origin);
 930                 if (real_git_dir)
 931                         die(_("options '%s' and '%s' cannot be used together"), "--bare", "--separate-git-dir");
 932                 option_no_checkout = 1;
 933         }
 934
 935         repo_name = argv[0];
 936
 937         path = get_repo_path(repo_name, &is_bundle);
 938         if (path) {
 939                 FREE_AND_NULL(path);
 940                 repo = absolute_pathdup(repo_name);
 941         } else if (strchr(repo_name, ':')) {
 942                 repo = repo_name;
 943                 display_repo = transport_anonymize_url(repo);
 944         } else
 945                 die(_("repository '%s' does not exist"), repo_name);
 946
 947         /* no need to be strict, transport_set_option() will validate it again */
 948         if (option_depth && atoi(option_depth) < 1)
 949                 die(_("depth %s is not a positive number"), option_depth);
 950
 951         if (argc == 2)
 952                 dir = xstrdup(argv[1]);
 953         else
 954                 dir = git_url_basename(repo_name, is_bundle, option_bare);
 955         strip_dir_trailing_slashes(dir);
 956
 957         dest_exists = path_exists(dir);
 958         if (dest_exists && !is_empty_dir(dir))
 959                 die(_("destination path '%s' already exists and is not "
 960                         "an empty directory."), dir);
 961
 962         if (real_git_dir) {
 963                 real_dest_exists = path_exists(real_git_dir);
 964                 if (real_dest_exists && !is_empty_dir(real_git_dir))
 965                         die(_("repository path '%s' already exists and is not "
 966                                 "an empty directory."), real_git_dir);
 967         }
 968
 969
 970         strbuf_addf(&reflog_msg, "clone: from %s",
 971                     display_repo ? display_repo : repo);
 972         free(display_repo);
 973
 974         if (option_bare)
 975                 work_tree = NULL;
 976         else {
 977                 work_tree = getenv("GIT_WORK_TREE");
 978                 if (work_tree && path_exists(work_tree))
 979                         die(_("working tree '%s' already exists."), work_tree);
 980         }
 981
 982         if (option_bare || work_tree)
 983                 git_dir = xstrdup(dir);
 984         else {
 985                 work_tree = dir;
 986                 git_dir = mkpathdup("%s/.git", dir);
 987         }
 988
 989         atexit(remove_junk);
 990         sigchain_push_common(remove_junk_on_signal);
 991
 992         if (!option_bare) {
 993                 if (safe_create_leading_directories_const(work_tree) < 0)
 994                         die_errno(_("could not create leading directories of '%s'"),
 995                                   work_tree);
 996                 if (dest_exists)
 997                         junk_work_tree_flags |= REMOVE_DIR_KEEP_TOPLEVEL;
 998                 else if (mkdir(work_tree, 0777))
 999                         die_errno(_("could not create work tree dir '%s'"),
1000                                   work_tree);
1001                 junk_work_tree = work_tree;
1002                 set_git_work_tree(work_tree);
1003         }
1004
1005         if (real_git_dir) {
1006                 if (real_dest_exists)
1007                         junk_git_dir_flags |= REMOVE_DIR_KEEP_TOPLEVEL;
1008                 junk_git_dir = real_git_dir;
1009         } else {
1010                 if (dest_exists)
1011                         junk_git_dir_flags |= REMOVE_DIR_KEEP_TOPLEVEL;
1012                 junk_git_dir = git_dir;
1013         }
1014         if (safe_create_leading_directories_const(git_dir) < 0)
1015                 die(_("could not create leading directories of '%s'"), git_dir);
1016
1017         if (0 <= option_verbosity) {
1018                 if (option_bare)
1019                         fprintf(stderr, _("Cloning into bare repository '%s'...\n"), dir);
1020                 else
1021                         fprintf(stderr, _("Cloning into '%s'...\n"), dir);
1022         }
1023
1024         if (option_recurse_submodules.nr > 0) {
1025                 struct string_list_item *item;
1026                 struct strbuf sb = STRBUF_INIT;
1027                 int val;
1028
1029                 /* remove duplicates */
1030                 string_list_sort(&option_recurse_submodules);
1031                 string_list_remove_duplicates(&option_recurse_submodules, 0);
1032
1033                 /*
1034                  * NEEDSWORK: In a multi-working-tree world, this needs to be
1035                  * set in the per-worktree config.
1036                  */
1037                 for_each_string_list_item(item, &option_recurse_submodules) {
1038                         strbuf_addf(&sb, "submodule.active=%s",
1039                                     item->string);
1040                         string_list_append(&option_config,
1041                                            strbuf_detach(&sb, NULL));
1042                 }
1043
1044                 if (!git_config_get_bool("submodule.stickyRecursiveClone", &val) &&
1045                     val)
1046                         string_list_append(&option_config, "submodule.recurse=true");
1047
1048                 if (option_required_reference.nr &&
1049                     option_optional_reference.nr)
1050                         die(_("clone --recursive is not compatible with "
1051                               "both --reference and --reference-if-able"));
1052                 else if (option_required_reference.nr) {
1053                         string_list_append(&option_config,
1054                                 "submodule.alternateLocation=superproject");
1055                         string_list_append(&option_config,
1056                                 "submodule.alternateErrorStrategy=die");
1057                 } else if (option_optional_reference.nr) {
1058                         string_list_append(&option_config,
1059                                 "submodule.alternateLocation=superproject");
1060                         string_list_append(&option_config,
1061                                 "submodule.alternateErrorStrategy=info");
1062                 }
1063         }
1064
1065         init_db(git_dir, real_git_dir, option_template, GIT_HASH_UNKNOWN, NULL,
1066                 INIT_DB_QUIET);
1067
1068         if (real_git_dir) {
1069                 free((char *)git_dir);
1070                 git_dir = real_git_dir;
1071         }
1072
1073         /*
1074          * additional config can be injected with -c, make sure it's included
1075          * after init_db, which clears the entire config environment.
1076          */
1077         write_config(&option_config);
1078
1079         /*
1080          * re-read config after init_db and write_config to pick up any config
1081          * injected by --template and --config, respectively.
1082          */
1083         git_config(git_clone_config, NULL);
1084
1085         /*
1086          * If option_reject_shallow is specified from CLI option,
1087          * ignore config_reject_shallow from git_clone_config.
1088          */
1089         if (config_reject_shallow != -1)
1090                 reject_shallow = config_reject_shallow;
1091         if (option_reject_shallow != -1)
1092                 reject_shallow = option_reject_shallow;
1093
1094         /*
1095          * If option_filter_submodules is specified from CLI option,
1096          * ignore config_filter_submodules from git_clone_config.
1097          */
1098         if (config_filter_submodules != -1)
1099                 filter_submodules = config_filter_submodules;
1100         if (option_filter_submodules != -1)
1101                 filter_submodules = option_filter_submodules;
1102
1103         /*
1104          * Exit if the user seems to be doing something silly with submodule
1105          * filter flags (but not with filter configs, as those should be
1106          * set-and-forget).
1107          */
1108         if (option_filter_submodules > 0 && !filter_options.choice)
1109                 die(_("the option '%s' requires '%s'"),
1110                     "--also-filter-submodules", "--filter");
1111         if (option_filter_submodules > 0 && !option_recurse_submodules.nr)
1112                 die(_("the option '%s' requires '%s'"),
1113                     "--also-filter-submodules", "--recurse-submodules");
1114
1115         /*
1116          * apply the remote name provided by --origin only after this second
1117          * call to git_config, to ensure it overrides all config-based values.
1118          */
1119         if (option_origin) {
1120                 free(remote_name);
1121                 remote_name = xstrdup(option_origin);
1122         }
1123
1124         if (!remote_name)
1125                 remote_name = xstrdup("origin");
1126
1127         if (!valid_remote_name(remote_name))
1128                 die(_("'%s' is not a valid remote name"), remote_name);
1129
1130         if (option_bare) {
1131                 if (option_mirror)
1132                         src_ref_prefix = "refs/";
1133                 strbuf_addstr(&branch_top, src_ref_prefix);
1134
1135                 git_config_set("core.bare", "true");
1136         } else {
1137                 strbuf_addf(&branch_top, "refs/remotes/%s/", remote_name);
1138         }
1139
1140         strbuf_addf(&key, "remote.%s.url", remote_name);
1141         git_config_set(key.buf, repo);
1142         strbuf_reset(&key);
1143
1144         if (option_no_tags) {
1145                 strbuf_addf(&key, "remote.%s.tagOpt", remote_name);
1146                 git_config_set(key.buf, "--no-tags");
1147                 strbuf_reset(&key);
1148         }
1149
1150         if (option_required_reference.nr || option_optional_reference.nr)
1151                 setup_reference();
1152
1153         if (option_sparse_checkout && git_sparse_checkout_init(dir))
1154                 return 1;
1155
1156         remote = remote_get(remote_name);
1157
1158         refspec_appendf(&remote->fetch, "+%s*:%s*", src_ref_prefix,
1159                         branch_top.buf);
1160
1161         transport = transport_get(remote, remote->url[0]);
1162         transport_set_verbosity(transport, option_verbosity, option_progress);
1163         transport->family = family;
1164
1165         path = get_repo_path(remote->url[0], &is_bundle);
1166         is_local = option_local != 0 && path && !is_bundle;
1167         if (is_local) {
1168                 if (option_depth)
1169                         warning(_("--depth is ignored in local clones; use file:// instead."));
1170                 if (option_since)
1171                         warning(_("--shallow-since is ignored in local clones; use file:// instead."));
1172                 if (option_not.nr)
1173                         warning(_("--shallow-exclude is ignored in local clones; use file:// instead."));
1174                 if (filter_options.choice)
1175                         warning(_("--filter is ignored in local clones; use file:// instead."));
1176                 if (!access(mkpath("%s/shallow", path), F_OK)) {
1177                         if (reject_shallow)
1178                                 die(_("source repository is shallow, reject to clone."));
1179                         if (option_local > 0)
1180                                 warning(_("source repository is shallow, ignoring --local"));
1181                         is_local = 0;
1182                 }
1183         }
1184         if (option_local > 0 && !is_local)
1185                 warning(_("--local is ignored"));
1186         transport->cloning = 1;
1187
1188         if (is_bundle) {
1189                 struct bundle_header header = BUNDLE_HEADER_INIT;
1190                 int fd = read_bundle_header(path, &header);
1191                 int has_filter = header.filter.choice != LOFC_DISABLED;
1192
1193                 if (fd > 0)
1194                         close(fd);
1195                 bundle_header_release(&header);
1196                 if (has_filter)
1197                         die(_("cannot clone from filtered bundle"));
1198         }
1199
1200         transport_set_option(transport, TRANS_OPT_KEEP, "yes");
1201
1202         if (reject_shallow)
1203                 transport_set_option(transport, TRANS_OPT_REJECT_SHALLOW, "1");
1204         if (option_depth)
1205                 transport_set_option(transport, TRANS_OPT_DEPTH,
1206                                      option_depth);
1207         if (option_since)
1208                 transport_set_option(transport, TRANS_OPT_DEEPEN_SINCE,
1209                                      option_since);
1210         if (option_not.nr)
1211                 transport_set_option(transport, TRANS_OPT_DEEPEN_NOT,
1212                                      (const char *)&option_not);
1213         if (option_single_branch)
1214                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
1215
1216         if (option_upload_pack)
1217                 transport_set_option(transport, TRANS_OPT_UPLOADPACK,
1218                                      option_upload_pack);
1219
1220         if (server_options.nr)
1221                 transport->server_options = &server_options;
1222
1223         if (filter_options.choice) {
1224                 const char *spec =
1225                         expand_list_objects_filter_spec(&filter_options);
1226                 transport_set_option(transport, TRANS_OPT_LIST_OBJECTS_FILTER,
1227                                      spec);
1228                 transport_set_option(transport, TRANS_OPT_FROM_PROMISOR, "1");
1229         }
1230
1231         if (transport->smart_options && !deepen && !filter_options.choice)
1232                 transport->smart_options->check_self_contained_and_connected = 1;
1233
1234
1235         strvec_push(&transport_ls_refs_options.ref_prefixes, "HEAD");
1236         refspec_ref_prefixes(&remote->fetch,
1237                              &transport_ls_refs_options.ref_prefixes);
1238         if (option_branch)
1239                 expand_ref_prefix(&transport_ls_refs_options.ref_prefixes,
1240                                   option_branch);
1241         if (!option_no_tags)
1242                 strvec_push(&transport_ls_refs_options.ref_prefixes,
1243                             "refs/tags/");
1244
1245         refs = transport_get_remote_refs(transport, &transport_ls_refs_options);
1246
1247         if (refs)
1248                 mapped_refs = wanted_peer_refs(refs, &remote->fetch);
1249
1250         if (mapped_refs) {
1251                 int hash_algo = hash_algo_by_ptr(transport_get_hash_algo(transport));
1252
1253                 /*
1254                  * Now that we know what algorithm the remote side is using,
1255                  * let's set ours to the same thing.
1256                  */
1257                 initialize_repository_version(hash_algo, 1);
1258                 repo_set_hash_algo(the_repository, hash_algo);
1259                 /*
1260                  * transport_get_remote_refs() may return refs with null sha-1
1261                  * in mapped_refs (see struct transport->get_refs_list
1262                  * comment). In that case we need fetch it early because
1263                  * remote_head code below relies on it.
1264                  *
1265                  * for normal clones, transport_get_remote_refs() should
1266                  * return reliable ref set, we can delay cloning until after
1267                  * remote HEAD check.
1268                  */
1269                 for (ref = refs; ref; ref = ref->next)
1270                         if (is_null_oid(&ref->old_oid)) {
1271                                 complete_refs_before_fetch = 0;
1272                                 break;
1273                         }
1274
1275                 if (!is_local && !complete_refs_before_fetch) {
1276                         if (transport_fetch_refs(transport, mapped_refs))
1277                                 die(_("remote transport reported error"));
1278                 }
1279         }
1280
1281         remote_head = find_ref_by_name(refs, "HEAD");
1282         remote_head_points_at = guess_remote_head(remote_head, mapped_refs, 0);
1283
1284         if (option_branch) {
1285                 our_head_points_at = find_remote_branch(mapped_refs, option_branch);
1286                 if (!our_head_points_at)
1287                         die(_("Remote branch %s not found in upstream %s"),
1288                             option_branch, remote_name);
1289         } else if (remote_head_points_at) {
1290                 our_head_points_at = remote_head_points_at;
1291         } else if (remote_head) {
1292                 our_head_points_at = NULL;
1293         } else {
1294                 const char *branch;
1295
1296                 if (!mapped_refs) {
1297                         warning(_("You appear to have cloned an empty repository."));
1298                         option_no_checkout = 1;
1299                 }
1300
1301                 if (transport_ls_refs_options.unborn_head_target &&
1302                     skip_prefix(transport_ls_refs_options.unborn_head_target,
1303                                 "refs/heads/", &branch)) {
1304                         unborn_head  = xstrdup(transport_ls_refs_options.unborn_head_target);
1305                 } else {
1306                         branch = git_default_branch_name(0);
1307                         unborn_head = xstrfmt("refs/heads/%s", branch);
1308                 }
1309
1310                 /*
1311                  * We may have selected a local default branch name "foo",
1312                  * and even though the remote's HEAD does not point there,
1313                  * it may still have a "foo" branch. If so, set it up so
1314                  * that we can follow the usual checkout code later.
1315                  *
1316                  * Note that for an empty repo we'll already have set
1317                  * option_no_checkout above, which would work against us here.
1318                  * But for an empty repo, find_remote_branch() can never find
1319                  * a match.
1320                  */
1321                 our_head_points_at = find_remote_branch(mapped_refs, branch);
1322         }
1323
1324         write_refspec_config(src_ref_prefix, our_head_points_at,
1325                         remote_head_points_at, &branch_top);
1326
1327         if (filter_options.choice)
1328                 partial_clone_register(remote_name, &filter_options);
1329
1330         if (is_local)
1331                 clone_local(path, git_dir);
1332         else if (mapped_refs && complete_refs_before_fetch) {
1333                 if (transport_fetch_refs(transport, mapped_refs))
1334                         die(_("remote transport reported error"));
1335         }
1336
1337         update_remote_refs(refs, mapped_refs, remote_head_points_at,
1338                            branch_top.buf, reflog_msg.buf, transport,
1339                            !is_local);
1340
1341         update_head(our_head_points_at, remote_head, unborn_head, reflog_msg.buf);
1342
1343         /*
1344          * We want to show progress for recursive submodule clones iff
1345          * we did so for the main clone. But only the transport knows
1346          * the final decision for this flag, so we need to rescue the value
1347          * before we free the transport.
1348          */
1349         submodule_progress = transport->progress;
1350
1351         transport_unlock_pack(transport, 0);
1352         transport_disconnect(transport);
1353
1354         if (option_dissociate) {
1355                 close_object_store(the_repository->objects);
1356                 dissociate_from_references();
1357         }
1358
1359         junk_mode = JUNK_LEAVE_REPO;
1360         err = checkout(submodule_progress, filter_submodules);
1361
1362         free(remote_name);
1363         strbuf_release(&reflog_msg);
1364         strbuf_release(&branch_top);
1365         strbuf_release(&key);
1366         free_refs(mapped_refs);
1367         free_refs(remote_head_points_at);
1368         free(unborn_head);
1369         free(dir);
1370         free(path);
1371         UNLEAK(repo);
1372         junk_mode = JUNK_LEAVE_ALL;
1373
1374         transport_ls_refs_options_release(&transport_ls_refs_options);
1375         return err;
1376 }