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 "lockfile.h"
  13 #include "parse-options.h"
  14 #include "fetch-pack.h"
  15 #include "refs.h"
  16 #include "tree.h"
  17 #include "tree-walk.h"
  18 #include "unpack-trees.h"
  19 #include "transport.h"
  20 #include "strbuf.h"
  21 #include "dir.h"
  22 #include "sigchain.h"
  23 #include "branch.h"
  24 #include "remote.h"
  25 #include "run-command.h"
  26 #include "connected.h"
  27
  28 /*
  29  * Overall FIXMEs:
  30  *  - respect DB_ENVIRONMENT for .git/objects.
  31  *
  32  * Implementation notes:
  33  *  - dropping use-separate-remote and no-separate-remote compatibility
  34  *
  35  */
  36 static const char * const builtin_clone_usage[] = {
  37         N_("git clone [<options>] [--] <repo> [<dir>]"),
  38         NULL
  39 };
  40
  41 static int option_no_checkout, option_bare, option_mirror, option_single_branch = -1;
  42 static int option_local = -1, option_no_hardlinks, option_shared, option_recursive;
  43 static char *option_template, *option_depth;
  44 static char *option_origin = NULL;
  45 static char *option_branch = NULL;
  46 static const char *real_git_dir;
  47 static char *option_upload_pack = "git-upload-pack";
  48 static int option_verbosity;
  49 static int option_progress = -1;
  50 static enum transport_family family;
  51 static struct string_list option_config;
  52 static struct string_list option_reference;
  53 static int option_dissociate;
  54 static int max_jobs = -1;
  55
  56 static struct option builtin_clone_options[] = {
  57         OPT__VERBOSITY(&option_verbosity),
  58         OPT_BOOL(0, "progress", &option_progress,
  59                  N_("force progress reporting")),
  60         OPT_BOOL('n', "no-checkout", &option_no_checkout,
  61                  N_("don't create a checkout")),
  62         OPT_BOOL(0, "bare", &option_bare, N_("create a bare repository")),
  63         OPT_HIDDEN_BOOL(0, "naked", &option_bare,
  64                         N_("create a bare repository")),
  65         OPT_BOOL(0, "mirror", &option_mirror,
  66                  N_("create a mirror repository (implies bare)")),
  67         OPT_BOOL('l', "local", &option_local,
  68                 N_("to clone from a local repository")),
  69         OPT_BOOL(0, "no-hardlinks", &option_no_hardlinks,
  70                     N_("don't use local hardlinks, always copy")),
  71         OPT_BOOL('s', "shared", &option_shared,
  72                     N_("setup as shared repository")),
  73         OPT_BOOL(0, "recursive", &option_recursive,
  74                     N_("initialize submodules in the clone")),
  75         OPT_BOOL(0, "recurse-submodules", &option_recursive,
  76                     N_("initialize submodules in the clone")),
  77         OPT_INTEGER('j', "jobs", &max_jobs,
  78                     N_("number of submodules cloned in parallel")),
  79         OPT_STRING(0, "template", &option_template, N_("template-directory"),
  80                    N_("directory from which templates will be used")),
  81         OPT_STRING_LIST(0, "reference", &option_reference, N_("repo"),
  82                         N_("reference repository")),
  83         OPT_BOOL(0, "dissociate", &option_dissociate,
  84                  N_("use --reference only while cloning")),
  85         OPT_STRING('o', "origin", &option_origin, N_("name"),
  86                    N_("use <name> instead of 'origin' to track upstream")),
  87         OPT_STRING('b', "branch", &option_branch, N_("branch"),
  88                    N_("checkout <branch> instead of the remote's HEAD")),
  89         OPT_STRING('u', "upload-pack", &option_upload_pack, N_("path"),
  90                    N_("path to git-upload-pack on the remote")),
  91         OPT_STRING(0, "depth", &option_depth, N_("depth"),
  92                     N_("create a shallow clone of that depth")),
  93         OPT_BOOL(0, "single-branch", &option_single_branch,
  94                     N_("clone only one branch, HEAD or --branch")),
  95         OPT_STRING(0, "separate-git-dir", &real_git_dir, N_("gitdir"),
  96                    N_("separate git dir from working tree")),
  97         OPT_STRING_LIST('c', "config", &option_config, N_("key=value"),
  98                         N_("set config inside the new repository")),
  99         OPT_SET_INT('4', "ipv4", &family, N_("use IPv4 addresses only"),
 100                         TRANSPORT_FAMILY_IPV4),
 101         OPT_SET_INT('6', "ipv6", &family, N_("use IPv6 addresses only"),
 102                         TRANSPORT_FAMILY_IPV6),
 103         OPT_END()
 104 };
 105
 106 static const char *get_repo_path_1(struct strbuf *path, int *is_bundle)
 107 {
 108         static char *suffix[] = { "/.git", "", ".git/.git", ".git" };
 109         static char *bundle_suffix[] = { ".bundle", "" };
 110         size_t baselen = path->len;
 111         struct stat st;
 112         int i;
 113
 114         for (i = 0; i < ARRAY_SIZE(suffix); i++) {
 115                 strbuf_setlen(path, baselen);
 116                 strbuf_addstr(path, suffix[i]);
 117                 if (stat(path->buf, &st))
 118                         continue;
 119                 if (S_ISDIR(st.st_mode) && is_git_directory(path->buf)) {
 120                         *is_bundle = 0;
 121                         return path->buf;
 122                 } else if (S_ISREG(st.st_mode) && st.st_size > 8) {
 123                         /* Is it a "gitfile"? */
 124                         char signature[8];
 125                         const char *dst;
 126                         int len, fd = open(path->buf, O_RDONLY);
 127                         if (fd < 0)
 128                                 continue;
 129                         len = read_in_full(fd, signature, 8);
 130                         close(fd);
 131                         if (len != 8 || strncmp(signature, "gitdir: ", 8))
 132                                 continue;
 133                         dst = read_gitfile(path->buf);
 134                         if (dst) {
 135                                 *is_bundle = 0;
 136                                 return dst;
 137                         }
 138                 }
 139         }
 140
 141         for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
 142                 strbuf_setlen(path, baselen);
 143                 strbuf_addstr(path, bundle_suffix[i]);
 144                 if (!stat(path->buf, &st) && S_ISREG(st.st_mode)) {
 145                         *is_bundle = 1;
 146                         return path->buf;
 147                 }
 148         }
 149
 150         return NULL;
 151 }
 152
 153 static char *get_repo_path(const char *repo, int *is_bundle)
 154 {
 155         struct strbuf path = STRBUF_INIT;
 156         const char *raw;
 157         char *canon;
 158
 159         strbuf_addstr(&path, repo);
 160         raw = get_repo_path_1(&path, is_bundle);
 161         canon = raw ? xstrdup(absolute_path(raw)) : NULL;
 162         strbuf_release(&path);
 163         return canon;
 164 }
 165
 166 static char *guess_dir_name(const char *repo, int is_bundle, int is_bare)
 167 {
 168         const char *end = repo + strlen(repo), *start, *ptr;
 169         size_t len;
 170         char *dir;
 171
 172         /*
 173          * Skip scheme.
 174          */
 175         start = strstr(repo, "://");
 176         if (start == NULL)
 177                 start = repo;
 178         else
 179                 start += 3;
 180
 181         /*
 182          * Skip authentication data. The stripping does happen
 183          * greedily, such that we strip up to the last '@' inside
 184          * the host part.
 185          */
 186         for (ptr = start; ptr < end && !is_dir_sep(*ptr); ptr++) {
 187                 if (*ptr == '@')
 188                         start = ptr + 1;
 189         }
 190
 191         /*
 192          * Strip trailing spaces, slashes and /.git
 193          */
 194         while (start < end && (is_dir_sep(end[-1]) || isspace(end[-1])))
 195                 end--;
 196         if (end - start > 5 && is_dir_sep(end[-5]) &&
 197             !strncmp(end - 4, ".git", 4)) {
 198                 end -= 5;
 199                 while (start < end && is_dir_sep(end[-1]))
 200                         end--;
 201         }
 202
 203         /*
 204          * Strip trailing port number if we've got only a
 205          * hostname (that is, there is no dir separator but a
 206          * colon). This check is required such that we do not
 207          * strip URI's like '/foo/bar:2222.git', which should
 208          * result in a dir '2222' being guessed due to backwards
 209          * compatibility.
 210          */
 211         if (memchr(start, '/', end - start) == NULL
 212             && memchr(start, ':', end - start) != NULL) {
 213                 ptr = end;
 214                 while (start < ptr && isdigit(ptr[-1]) && ptr[-1] != ':')
 215                         ptr--;
 216                 if (start < ptr && ptr[-1] == ':')
 217                         end = ptr - 1;
 218         }
 219
 220         /*
 221          * Find last component. To remain backwards compatible we
 222          * also regard colons as path separators, such that
 223          * cloning a repository 'foo:bar.git' would result in a
 224          * directory 'bar' being guessed.
 225          */
 226         ptr = end;
 227         while (start < ptr && !is_dir_sep(ptr[-1]) && ptr[-1] != ':')
 228                 ptr--;
 229         start = ptr;
 230
 231         /*
 232          * Strip .{bundle,git}.
 233          */
 234         len = end - start;
 235         strip_suffix_mem(start, &len, is_bundle ? ".bundle" : ".git");
 236
 237         if (!len || (len == 1 && *start == '/'))
 238                 die(_("No directory name could be guessed.\n"
 239                       "Please specify a directory on the command line"));
 240
 241         if (is_bare)
 242                 dir = xstrfmt("%.*s.git", (int)len, start);
 243         else
 244                 dir = xstrndup(start, len);
 245         /*
 246          * Replace sequences of 'control' characters and whitespace
 247          * with one ascii space, remove leading and trailing spaces.
 248          */
 249         if (*dir) {
 250                 char *out = dir;
 251                 int prev_space = 1 /* strip leading whitespace */;
 252                 for (end = dir; *end; ++end) {
 253                         char ch = *end;
 254                         if ((unsigned char)ch < '\x20')
 255                                 ch = '\x20';
 256                         if (isspace(ch)) {
 257                                 if (prev_space)
 258                                         continue;
 259                                 prev_space = 1;
 260                         } else
 261                                 prev_space = 0;
 262                         *out++ = ch;
 263                 }
 264                 *out = '\0';
 265                 if (out > dir && prev_space)
 266                         out[-1] = '\0';
 267         }
 268         return dir;
 269 }
 270
 271 static void strip_trailing_slashes(char *dir)
 272 {
 273         char *end = dir + strlen(dir);
 274
 275         while (dir < end - 1 && is_dir_sep(end[-1]))
 276                 end--;
 277         *end = '\0';
 278 }
 279
 280 static int add_one_reference(struct string_list_item *item, void *cb_data)
 281 {
 282         char *ref_git;
 283         const char *repo;
 284         struct strbuf alternate = STRBUF_INIT;
 285
 286         /* Beware: read_gitfile(), real_path() and mkpath() return static buffer */
 287         ref_git = xstrdup(real_path(item->string));
 288
 289         repo = read_gitfile(ref_git);
 290         if (!repo)
 291                 repo = read_gitfile(mkpath("%s/.git", ref_git));
 292         if (repo) {
 293                 free(ref_git);
 294                 ref_git = xstrdup(repo);
 295         }
 296
 297         if (!repo && is_directory(mkpath("%s/.git/objects", ref_git))) {
 298                 char *ref_git_git = mkpathdup("%s/.git", ref_git);
 299                 free(ref_git);
 300                 ref_git = ref_git_git;
 301         } else if (!is_directory(mkpath("%s/objects", ref_git))) {
 302                 struct strbuf sb = STRBUF_INIT;
 303                 if (get_common_dir(&sb, ref_git))
 304                         die(_("reference repository '%s' as a linked checkout is not supported yet."),
 305                             item->string);
 306                 die(_("reference repository '%s' is not a local repository."),
 307                     item->string);
 308         }
 309
 310         if (!access(mkpath("%s/shallow", ref_git), F_OK))
 311                 die(_("reference repository '%s' is shallow"), item->string);
 312
 313         if (!access(mkpath("%s/info/grafts", ref_git), F_OK))
 314                 die(_("reference repository '%s' is grafted"), item->string);
 315
 316         strbuf_addf(&alternate, "%s/objects", ref_git);
 317         add_to_alternates_file(alternate.buf);
 318         strbuf_release(&alternate);
 319         free(ref_git);
 320         return 0;
 321 }
 322
 323 static void setup_reference(void)
 324 {
 325         for_each_string_list(&option_reference, add_one_reference, NULL);
 326 }
 327
 328 static void copy_alternates(struct strbuf *src, struct strbuf *dst,
 329                             const char *src_repo)
 330 {
 331         /*
 332          * Read from the source objects/info/alternates file
 333          * and copy the entries to corresponding file in the
 334          * destination repository with add_to_alternates_file().
 335          * Both src and dst have "$path/objects/info/alternates".
 336          *
 337          * Instead of copying bit-for-bit from the original,
 338          * we need to append to existing one so that the already
 339          * created entry via "clone -s" is not lost, and also
 340          * to turn entries with paths relative to the original
 341          * absolute, so that they can be used in the new repository.
 342          */
 343         FILE *in = fopen(src->buf, "r");
 344         struct strbuf line = STRBUF_INIT;
 345
 346         while (strbuf_getline(&line, in) != EOF) {
 347                 char *abs_path;
 348                 if (!line.len || line.buf[0] == '#')
 349                         continue;
 350                 if (is_absolute_path(line.buf)) {
 351                         add_to_alternates_file(line.buf);
 352                         continue;
 353                 }
 354                 abs_path = mkpathdup("%s/objects/%s", src_repo, line.buf);
 355                 normalize_path_copy(abs_path, abs_path);
 356                 add_to_alternates_file(abs_path);
 357                 free(abs_path);
 358         }
 359         strbuf_release(&line);
 360         fclose(in);
 361 }
 362
 363 static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
 364                                    const char *src_repo, int src_baselen)
 365 {
 366         struct dirent *de;
 367         struct stat buf;
 368         int src_len, dest_len;
 369         DIR *dir;
 370
 371         dir = opendir(src->buf);
 372         if (!dir)
 373                 die_errno(_("failed to open '%s'"), src->buf);
 374
 375         if (mkdir(dest->buf, 0777)) {
 376                 if (errno != EEXIST)
 377                         die_errno(_("failed to create directory '%s'"), dest->buf);
 378                 else if (stat(dest->buf, &buf))
 379                         die_errno(_("failed to stat '%s'"), dest->buf);
 380                 else if (!S_ISDIR(buf.st_mode))
 381                         die(_("%s exists and is not a directory"), dest->buf);
 382         }
 383
 384         strbuf_addch(src, '/');
 385         src_len = src->len;
 386         strbuf_addch(dest, '/');
 387         dest_len = dest->len;
 388
 389         while ((de = readdir(dir)) != NULL) {
 390                 strbuf_setlen(src, src_len);
 391                 strbuf_addstr(src, de->d_name);
 392                 strbuf_setlen(dest, dest_len);
 393                 strbuf_addstr(dest, de->d_name);
 394                 if (stat(src->buf, &buf)) {
 395                         warning (_("failed to stat %s\n"), src->buf);
 396                         continue;
 397                 }
 398                 if (S_ISDIR(buf.st_mode)) {
 399                         if (de->d_name[0] != '.')
 400                                 copy_or_link_directory(src, dest,
 401                                                        src_repo, src_baselen);
 402                         continue;
 403                 }
 404
 405                 /* Files that cannot be copied bit-for-bit... */
 406                 if (!strcmp(src->buf + src_baselen, "/info/alternates")) {
 407                         copy_alternates(src, dest, src_repo);
 408                         continue;
 409                 }
 410
 411                 if (unlink(dest->buf) && errno != ENOENT)
 412                         die_errno(_("failed to unlink '%s'"), dest->buf);
 413                 if (!option_no_hardlinks) {
 414                         if (!link(src->buf, dest->buf))
 415                                 continue;
 416                         if (option_local > 0)
 417                                 die_errno(_("failed to create link '%s'"), dest->buf);
 418                         option_no_hardlinks = 1;
 419                 }
 420                 if (copy_file_with_time(dest->buf, src->buf, 0666))
 421                         die_errno(_("failed to copy file to '%s'"), dest->buf);
 422         }
 423         closedir(dir);
 424 }
 425
 426 static void clone_local(const char *src_repo, const char *dest_repo)
 427 {
 428         if (option_shared) {
 429                 struct strbuf alt = STRBUF_INIT;
 430                 strbuf_addf(&alt, "%s/objects", src_repo);
 431                 add_to_alternates_file(alt.buf);
 432                 strbuf_release(&alt);
 433         } else {
 434                 struct strbuf src = STRBUF_INIT;
 435                 struct strbuf dest = STRBUF_INIT;
 436                 get_common_dir(&src, src_repo);
 437                 get_common_dir(&dest, dest_repo);
 438                 strbuf_addstr(&src, "/objects");
 439                 strbuf_addstr(&dest, "/objects");
 440                 copy_or_link_directory(&src, &dest, src_repo, src.len);
 441                 strbuf_release(&src);
 442                 strbuf_release(&dest);
 443         }
 444
 445         if (0 <= option_verbosity)
 446                 fprintf(stderr, _("done.\n"));
 447 }
 448
 449 static const char *junk_work_tree;
 450 static const char *junk_git_dir;
 451 static enum {
 452         JUNK_LEAVE_NONE,
 453         JUNK_LEAVE_REPO,
 454         JUNK_LEAVE_ALL
 455 } junk_mode = JUNK_LEAVE_NONE;
 456
 457 static const char junk_leave_repo_msg[] =
 458 N_("Clone succeeded, but checkout failed.\n"
 459    "You can inspect what was checked out with 'git status'\n"
 460    "and retry the checkout with 'git checkout -f HEAD'\n");
 461
 462 static void remove_junk(void)
 463 {
 464         struct strbuf sb = STRBUF_INIT;
 465
 466         switch (junk_mode) {
 467         case JUNK_LEAVE_REPO:
 468                 warning("%s", _(junk_leave_repo_msg));
 469                 /* fall-through */
 470         case JUNK_LEAVE_ALL:
 471                 return;
 472         default:
 473                 /* proceed to removal */
 474                 break;
 475         }
 476
 477         if (junk_git_dir) {
 478                 strbuf_addstr(&sb, junk_git_dir);
 479                 remove_dir_recursively(&sb, 0);
 480                 strbuf_reset(&sb);
 481         }
 482         if (junk_work_tree) {
 483                 strbuf_addstr(&sb, junk_work_tree);
 484                 remove_dir_recursively(&sb, 0);
 485                 strbuf_reset(&sb);
 486         }
 487 }
 488
 489 static void remove_junk_on_signal(int signo)
 490 {
 491         remove_junk();
 492         sigchain_pop(signo);
 493         raise(signo);
 494 }
 495
 496 static struct ref *find_remote_branch(const struct ref *refs, const char *branch)
 497 {
 498         struct ref *ref;
 499         struct strbuf head = STRBUF_INIT;
 500         strbuf_addstr(&head, "refs/heads/");
 501         strbuf_addstr(&head, branch);
 502         ref = find_ref_by_name(refs, head.buf);
 503         strbuf_release(&head);
 504
 505         if (ref)
 506                 return ref;
 507
 508         strbuf_addstr(&head, "refs/tags/");
 509         strbuf_addstr(&head, branch);
 510         ref = find_ref_by_name(refs, head.buf);
 511         strbuf_release(&head);
 512
 513         return ref;
 514 }
 515
 516 static struct ref *wanted_peer_refs(const struct ref *refs,
 517                 struct refspec *refspec)
 518 {
 519         struct ref *head = copy_ref(find_ref_by_name(refs, "HEAD"));
 520         struct ref *local_refs = head;
 521         struct ref **tail = head ? &head->next : &local_refs;
 522
 523         if (option_single_branch) {
 524                 struct ref *remote_head = NULL;
 525
 526                 if (!option_branch)
 527                         remote_head = guess_remote_head(head, refs, 0);
 528                 else {
 529                         local_refs = NULL;
 530                         tail = &local_refs;
 531                         remote_head = copy_ref(find_remote_branch(refs, option_branch));
 532                 }
 533
 534                 if (!remote_head && option_branch)
 535                         warning(_("Could not find remote branch %s to clone."),
 536                                 option_branch);
 537                 else {
 538                         get_fetch_map(remote_head, refspec, &tail, 0);
 539
 540                         /* if --branch=tag, pull the requested tag explicitly */
 541                         get_fetch_map(remote_head, tag_refspec, &tail, 0);
 542                 }
 543         } else
 544                 get_fetch_map(refs, refspec, &tail, 0);
 545
 546         if (!option_mirror && !option_single_branch)
 547                 get_fetch_map(refs, tag_refspec, &tail, 0);
 548
 549         return local_refs;
 550 }
 551
 552 static void write_remote_refs(const struct ref *local_refs)
 553 {
 554         const struct ref *r;
 555
 556         struct ref_transaction *t;
 557         struct strbuf err = STRBUF_INIT;
 558
 559         t = ref_transaction_begin(&err);
 560         if (!t)
 561                 die("%s", err.buf);
 562
 563         for (r = local_refs; r; r = r->next) {
 564                 if (!r->peer_ref)
 565                         continue;
 566                 if (ref_transaction_create(t, r->peer_ref->name, r->old_oid.hash,
 567                                            0, NULL, &err))
 568                         die("%s", err.buf);
 569         }
 570
 571         if (initial_ref_transaction_commit(t, &err))
 572                 die("%s", err.buf);
 573
 574         strbuf_release(&err);
 575         ref_transaction_free(t);
 576 }
 577
 578 static void write_followtags(const struct ref *refs, const char *msg)
 579 {
 580         const struct ref *ref;
 581         for (ref = refs; ref; ref = ref->next) {
 582                 if (!starts_with(ref->name, "refs/tags/"))
 583                         continue;
 584                 if (ends_with(ref->name, "^{}"))
 585                         continue;
 586                 if (!has_object_file(&ref->old_oid))
 587                         continue;
 588                 update_ref(msg, ref->name, ref->old_oid.hash,
 589                            NULL, 0, UPDATE_REFS_DIE_ON_ERR);
 590         }
 591 }
 592
 593 static int iterate_ref_map(void *cb_data, unsigned char sha1[20])
 594 {
 595         struct ref **rm = cb_data;
 596         struct ref *ref = *rm;
 597
 598         /*
 599          * Skip anything missing a peer_ref, which we are not
 600          * actually going to write a ref for.
 601          */
 602         while (ref && !ref->peer_ref)
 603                 ref = ref->next;
 604         /* Returning -1 notes "end of list" to the caller. */
 605         if (!ref)
 606                 return -1;
 607
 608         hashcpy(sha1, ref->old_oid.hash);
 609         *rm = ref->next;
 610         return 0;
 611 }
 612
 613 static void update_remote_refs(const struct ref *refs,
 614                                const struct ref *mapped_refs,
 615                                const struct ref *remote_head_points_at,
 616                                const char *branch_top,
 617                                const char *msg,
 618                                struct transport *transport,
 619                                int check_connectivity)
 620 {
 621         const struct ref *rm = mapped_refs;
 622
 623         if (check_connectivity) {
 624                 if (transport->progress)
 625                         fprintf(stderr, _("Checking connectivity... "));
 626                 if (check_everything_connected_with_transport(iterate_ref_map,
 627                                                               0, &rm, transport))
 628                         die(_("remote did not send all necessary objects"));
 629                 if (transport->progress)
 630                         fprintf(stderr, _("done.\n"));
 631         }
 632
 633         if (refs) {
 634                 write_remote_refs(mapped_refs);
 635                 if (option_single_branch)
 636                         write_followtags(refs, msg);
 637         }
 638
 639         if (remote_head_points_at && !option_bare) {
 640                 struct strbuf head_ref = STRBUF_INIT;
 641                 strbuf_addstr(&head_ref, branch_top);
 642                 strbuf_addstr(&head_ref, "HEAD");
 643                 if (create_symref(head_ref.buf,
 644                                   remote_head_points_at->peer_ref->name,
 645                                   msg) < 0)
 646                         die(_("unable to update %s"), head_ref.buf);
 647                 strbuf_release(&head_ref);
 648         }
 649 }
 650
 651 static void update_head(const struct ref *our, const struct ref *remote,
 652                         const char *msg)
 653 {
 654         const char *head;
 655         if (our && skip_prefix(our->name, "refs/heads/", &head)) {
 656                 /* Local default branch link */
 657                 if (create_symref("HEAD", our->name, NULL) < 0)
 658                         die(_("unable to update HEAD"));
 659                 if (!option_bare) {
 660                         update_ref(msg, "HEAD", our->old_oid.hash, NULL, 0,
 661                                    UPDATE_REFS_DIE_ON_ERR);
 662                         install_branch_config(0, head, option_origin, our->name);
 663                 }
 664         } else if (our) {
 665                 struct commit *c = lookup_commit_reference(our->old_oid.hash);
 666                 /* --branch specifies a non-branch (i.e. tags), detach HEAD */
 667                 update_ref(msg, "HEAD", c->object.oid.hash,
 668                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
 669         } else if (remote) {
 670                 /*
 671                  * We know remote HEAD points to a non-branch, or
 672                  * HEAD points to a branch but we don't know which one.
 673                  * Detach HEAD in all these cases.
 674                  */
 675                 update_ref(msg, "HEAD", remote->old_oid.hash,
 676                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
 677         }
 678 }
 679
 680 static int checkout(void)
 681 {
 682         unsigned char sha1[20];
 683         char *head;
 684         struct lock_file *lock_file;
 685         struct unpack_trees_options opts;
 686         struct tree *tree;
 687         struct tree_desc t;
 688         int err = 0;
 689
 690         if (option_no_checkout)
 691                 return 0;
 692
 693         head = resolve_refdup("HEAD", RESOLVE_REF_READING, sha1, NULL);
 694         if (!head) {
 695                 warning(_("remote HEAD refers to nonexistent ref, "
 696                           "unable to checkout.\n"));
 697                 return 0;
 698         }
 699         if (!strcmp(head, "HEAD")) {
 700                 if (advice_detached_head)
 701                         detach_advice(sha1_to_hex(sha1));
 702         } else {
 703                 if (!starts_with(head, "refs/heads/"))
 704                         die(_("HEAD not found below refs/heads!"));
 705         }
 706         free(head);
 707
 708         /* We need to be in the new work tree for the checkout */
 709         setup_work_tree();
 710
 711         lock_file = xcalloc(1, sizeof(struct lock_file));
 712         hold_locked_index(lock_file, 1);
 713
 714         memset(&opts, 0, sizeof opts);
 715         opts.update = 1;
 716         opts.merge = 1;
 717         opts.fn = oneway_merge;
 718         opts.verbose_update = (option_verbosity >= 0);
 719         opts.src_index = &the_index;
 720         opts.dst_index = &the_index;
 721
 722         tree = parse_tree_indirect(sha1);
 723         parse_tree(tree);
 724         init_tree_desc(&t, tree->buffer, tree->size);
 725         if (unpack_trees(1, &t, &opts) < 0)
 726                 die(_("unable to checkout working tree"));
 727
 728         if (write_locked_index(&the_index, lock_file, COMMIT_LOCK))
 729                 die(_("unable to write new index file"));
 730
 731         err |= run_hook_le(NULL, "post-checkout", sha1_to_hex(null_sha1),
 732                            sha1_to_hex(sha1), "1", NULL);
 733
 734         if (!err && option_recursive) {
 735                 struct argv_array args = ARGV_ARRAY_INIT;
 736                 argv_array_pushl(&args, "submodule", "update", "--init", "--recursive", NULL);
 737
 738                 if (max_jobs != -1)
 739                         argv_array_pushf(&args, "--jobs=%d", max_jobs);
 740
 741                 err = run_command_v_opt(args.argv, RUN_GIT_CMD);
 742                 argv_array_clear(&args);
 743         }
 744
 745         return err;
 746 }
 747
 748 static int write_one_config(const char *key, const char *value, void *data)
 749 {
 750         return git_config_set_multivar_gently(key, value ? value : "true", "^$", 0);
 751 }
 752
 753 static void write_config(struct string_list *config)
 754 {
 755         int i;
 756
 757         for (i = 0; i < config->nr; i++) {
 758                 if (git_config_parse_parameter(config->items[i].string,
 759                                                write_one_config, NULL) < 0)
 760                         die(_("unable to write parameters to config file"));
 761         }
 762 }
 763
 764 static void write_refspec_config(const char *src_ref_prefix,
 765                 const struct ref *our_head_points_at,
 766                 const struct ref *remote_head_points_at,
 767                 struct strbuf *branch_top)
 768 {
 769         struct strbuf key = STRBUF_INIT;
 770         struct strbuf value = STRBUF_INIT;
 771
 772         if (option_mirror || !option_bare) {
 773                 if (option_single_branch && !option_mirror) {
 774                         if (option_branch) {
 775                                 if (starts_with(our_head_points_at->name, "refs/tags/"))
 776                                         strbuf_addf(&value, "+%s:%s", our_head_points_at->name,
 777                                                 our_head_points_at->name);
 778                                 else
 779                                         strbuf_addf(&value, "+%s:%s%s", our_head_points_at->name,
 780                                                 branch_top->buf, option_branch);
 781                         } else if (remote_head_points_at) {
 782                                 const char *head = remote_head_points_at->name;
 783                                 if (!skip_prefix(head, "refs/heads/", &head))
 784                                         die("BUG: remote HEAD points at non-head?");
 785
 786                                 strbuf_addf(&value, "+%s:%s%s", remote_head_points_at->name,
 787                                                 branch_top->buf, head);
 788                         }
 789                         /*
 790                          * otherwise, the next "git fetch" will
 791                          * simply fetch from HEAD without updating
 792                          * any remote-tracking branch, which is what
 793                          * we want.
 794                          */
 795                 } else {
 796                         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top->buf);
 797                 }
 798                 /* Configure the remote */
 799                 if (value.len) {
 800                         strbuf_addf(&key, "remote.%s.fetch", option_origin);
 801                         git_config_set_multivar(key.buf, value.buf, "^$", 0);
 802                         strbuf_reset(&key);
 803
 804                         if (option_mirror) {
 805                                 strbuf_addf(&key, "remote.%s.mirror", option_origin);
 806                                 git_config_set(key.buf, "true");
 807                                 strbuf_reset(&key);
 808                         }
 809                 }
 810         }
 811
 812         strbuf_release(&key);
 813         strbuf_release(&value);
 814 }
 815
 816 static void dissociate_from_references(void)
 817 {
 818         static const char* argv[] = { "repack", "-a", "-d", NULL };
 819         char *alternates = git_pathdup("objects/info/alternates");
 820
 821         if (!access(alternates, F_OK)) {
 822                 if (run_command_v_opt(argv, RUN_GIT_CMD|RUN_COMMAND_NO_STDIN))
 823                         die(_("cannot repack to clean up"));
 824                 if (unlink(alternates) && errno != ENOENT)
 825                         die_errno(_("cannot unlink temporary alternates file"));
 826         }
 827         free(alternates);
 828 }
 829
 830 int cmd_clone(int argc, const char **argv, const char *prefix)
 831 {
 832         int is_bundle = 0, is_local;
 833         struct stat buf;
 834         const char *repo_name, *repo, *work_tree, *git_dir;
 835         char *path, *dir;
 836         int dest_exists;
 837         const struct ref *refs, *remote_head;
 838         const struct ref *remote_head_points_at;
 839         const struct ref *our_head_points_at;
 840         struct ref *mapped_refs;
 841         const struct ref *ref;
 842         struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
 843         struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
 844         struct transport *transport = NULL;
 845         const char *src_ref_prefix = "refs/heads/";
 846         struct remote *remote;
 847         int err = 0, complete_refs_before_fetch = 1;
 848
 849         struct refspec *refspec;
 850         const char *fetch_pattern;
 851
 852         packet_trace_identity("clone");
 853         argc = parse_options(argc, argv, prefix, builtin_clone_options,
 854                              builtin_clone_usage, 0);
 855
 856         if (argc > 2)
 857                 usage_msg_opt(_("Too many arguments."),
 858                         builtin_clone_usage, builtin_clone_options);
 859
 860         if (argc == 0)
 861                 usage_msg_opt(_("You must specify a repository to clone."),
 862                         builtin_clone_usage, builtin_clone_options);
 863
 864         if (option_single_branch == -1)
 865                 option_single_branch = option_depth ? 1 : 0;
 866
 867         if (option_mirror)
 868                 option_bare = 1;
 869
 870         if (option_bare) {
 871                 if (option_origin)
 872                         die(_("--bare and --origin %s options are incompatible."),
 873                             option_origin);
 874                 if (real_git_dir)
 875                         die(_("--bare and --separate-git-dir are incompatible."));
 876                 option_no_checkout = 1;
 877         }
 878
 879         if (!option_origin)
 880                 option_origin = "origin";
 881
 882         repo_name = argv[0];
 883
 884         path = get_repo_path(repo_name, &is_bundle);
 885         if (path)
 886                 repo = xstrdup(absolute_path(repo_name));
 887         else if (!strchr(repo_name, ':'))
 888                 die(_("repository '%s' does not exist"), repo_name);
 889         else
 890                 repo = repo_name;
 891
 892         /* no need to be strict, transport_set_option() will validate it again */
 893         if (option_depth && atoi(option_depth) < 1)
 894                 die(_("depth %s is not a positive number"), option_depth);
 895
 896         if (argc == 2)
 897                 dir = xstrdup(argv[1]);
 898         else
 899                 dir = guess_dir_name(repo_name, is_bundle, option_bare);
 900         strip_trailing_slashes(dir);
 901
 902         dest_exists = !stat(dir, &buf);
 903         if (dest_exists && !is_empty_dir(dir))
 904                 die(_("destination path '%s' already exists and is not "
 905                         "an empty directory."), dir);
 906
 907         strbuf_addf(&reflog_msg, "clone: from %s", repo);
 908
 909         if (option_bare)
 910                 work_tree = NULL;
 911         else {
 912                 work_tree = getenv("GIT_WORK_TREE");
 913                 if (work_tree && !stat(work_tree, &buf))
 914                         die(_("working tree '%s' already exists."), work_tree);
 915         }
 916
 917         if (option_bare || work_tree)
 918                 git_dir = xstrdup(dir);
 919         else {
 920                 work_tree = dir;
 921                 git_dir = mkpathdup("%s/.git", dir);
 922         }
 923
 924         atexit(remove_junk);
 925         sigchain_push_common(remove_junk_on_signal);
 926
 927         if (!option_bare) {
 928                 if (safe_create_leading_directories_const(work_tree) < 0)
 929                         die_errno(_("could not create leading directories of '%s'"),
 930                                   work_tree);
 931                 if (!dest_exists && mkdir(work_tree, 0777))
 932                         die_errno(_("could not create work tree dir '%s'"),
 933                                   work_tree);
 934                 junk_work_tree = work_tree;
 935                 set_git_work_tree(work_tree);
 936         }
 937
 938         junk_git_dir = git_dir;
 939         if (safe_create_leading_directories_const(git_dir) < 0)
 940                 die(_("could not create leading directories of '%s'"), git_dir);
 941
 942         set_git_dir_init(git_dir, real_git_dir, 0);
 943         if (real_git_dir) {
 944                 git_dir = real_git_dir;
 945                 junk_git_dir = real_git_dir;
 946         }
 947
 948         if (0 <= option_verbosity) {
 949                 if (option_bare)
 950                         fprintf(stderr, _("Cloning into bare repository '%s'...\n"), dir);
 951                 else
 952                         fprintf(stderr, _("Cloning into '%s'...\n"), dir);
 953         }
 954         init_db(option_template, INIT_DB_QUIET);
 955         write_config(&option_config);
 956
 957         git_config(git_default_config, NULL);
 958
 959         if (option_bare) {
 960                 if (option_mirror)
 961                         src_ref_prefix = "refs/";
 962                 strbuf_addstr(&branch_top, src_ref_prefix);
 963
 964                 git_config_set("core.bare", "true");
 965         } else {
 966                 strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
 967         }
 968
 969         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top.buf);
 970         strbuf_addf(&key, "remote.%s.url", option_origin);
 971         git_config_set(key.buf, repo);
 972         strbuf_reset(&key);
 973
 974         if (option_reference.nr)
 975                 setup_reference();
 976
 977         fetch_pattern = value.buf;
 978         refspec = parse_fetch_refspec(1, &fetch_pattern);
 979
 980         strbuf_reset(&value);
 981
 982         remote = remote_get(option_origin);
 983         transport = transport_get(remote, remote->url[0]);
 984         transport_set_verbosity(transport, option_verbosity, option_progress);
 985         transport->family = family;
 986
 987         path = get_repo_path(remote->url[0], &is_bundle);
 988         is_local = option_local != 0 && path && !is_bundle;
 989         if (is_local) {
 990                 if (option_depth)
 991                         warning(_("--depth is ignored in local clones; use file:// instead."));
 992                 if (!access(mkpath("%s/shallow", path), F_OK)) {
 993                         if (option_local > 0)
 994                                 warning(_("source repository is shallow, ignoring --local"));
 995                         is_local = 0;
 996                 }
 997         }
 998         if (option_local > 0 && !is_local)
 999                 warning(_("--local is ignored"));
1000         transport->cloning = 1;
1001
1002         if (!transport->get_refs_list || (!is_local && !transport->fetch))
1003                 die(_("Don't know how to clone %s"), transport->url);
1004
1005         transport_set_option(transport, TRANS_OPT_KEEP, "yes");
1006
1007         if (option_depth)
1008                 transport_set_option(transport, TRANS_OPT_DEPTH,
1009                                      option_depth);
1010         if (option_single_branch)
1011                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
1012
1013         if (option_upload_pack)
1014                 transport_set_option(transport, TRANS_OPT_UPLOADPACK,
1015                                      option_upload_pack);
1016
1017         if (transport->smart_options && !option_depth)
1018                 transport->smart_options->check_self_contained_and_connected = 1;
1019
1020         refs = transport_get_remote_refs(transport);
1021
1022         if (refs) {
1023                 mapped_refs = wanted_peer_refs(refs, refspec);
1024                 /*
1025                  * transport_get_remote_refs() may return refs with null sha-1
1026                  * in mapped_refs (see struct transport->get_refs_list
1027                  * comment). In that case we need fetch it early because
1028                  * remote_head code below relies on it.
1029                  *
1030                  * for normal clones, transport_get_remote_refs() should
1031                  * return reliable ref set, we can delay cloning until after
1032                  * remote HEAD check.
1033                  */
1034                 for (ref = refs; ref; ref = ref->next)
1035                         if (is_null_oid(&ref->old_oid)) {
1036                                 complete_refs_before_fetch = 0;
1037                                 break;
1038                         }
1039
1040                 if (!is_local && !complete_refs_before_fetch)
1041                         transport_fetch_refs(transport, mapped_refs);
1042
1043                 remote_head = find_ref_by_name(refs, "HEAD");
1044                 remote_head_points_at =
1045                         guess_remote_head(remote_head, mapped_refs, 0);
1046
1047                 if (option_branch) {
1048                         our_head_points_at =
1049                                 find_remote_branch(mapped_refs, option_branch);
1050
1051                         if (!our_head_points_at)
1052                                 die(_("Remote branch %s not found in upstream %s"),
1053                                     option_branch, option_origin);
1054                 }
1055                 else
1056                         our_head_points_at = remote_head_points_at;
1057         }
1058         else {
1059                 if (option_branch)
1060                         die(_("Remote branch %s not found in upstream %s"),
1061                                         option_branch, option_origin);
1062
1063                 warning(_("You appear to have cloned an empty repository."));
1064                 mapped_refs = NULL;
1065                 our_head_points_at = NULL;
1066                 remote_head_points_at = NULL;
1067                 remote_head = NULL;
1068                 option_no_checkout = 1;
1069                 if (!option_bare)
1070                         install_branch_config(0, "master", option_origin,
1071                                               "refs/heads/master");
1072         }
1073
1074         write_refspec_config(src_ref_prefix, our_head_points_at,
1075                         remote_head_points_at, &branch_top);
1076
1077         if (is_local)
1078                 clone_local(path, git_dir);
1079         else if (refs && complete_refs_before_fetch)
1080                 transport_fetch_refs(transport, mapped_refs);
1081
1082         update_remote_refs(refs, mapped_refs, remote_head_points_at,
1083                            branch_top.buf, reflog_msg.buf, transport, !is_local);
1084
1085         update_head(our_head_points_at, remote_head, reflog_msg.buf);
1086
1087         transport_unlock_pack(transport);
1088         transport_disconnect(transport);
1089
1090         if (option_dissociate) {
1091                 close_all_packs();
1092                 dissociate_from_references();
1093         }
1094
1095         junk_mode = JUNK_LEAVE_REPO;
1096         err = checkout();
1097
1098         strbuf_release(&reflog_msg);
1099         strbuf_release(&branch_top);
1100         strbuf_release(&key);
1101         strbuf_release(&value);
1102         junk_mode = JUNK_LEAVE_ALL;
1103
1104         free(refspec);
1105         return err;
1106 }