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 int option_shallow_submodules;
  44 static char *option_template, *option_depth;
  45 static char *option_origin = NULL;
  46 static char *option_branch = NULL;
  47 static const char *real_git_dir;
  48 static char *option_upload_pack = "git-upload-pack";
  49 static int option_verbosity;
  50 static int option_progress = -1;
  51 static enum transport_family family;
  52 static struct string_list option_config = STRING_LIST_INIT_NODUP;
  53 static struct string_list option_required_reference = STRING_LIST_INIT_NODUP;
  54 static struct string_list option_optional_reference = STRING_LIST_INIT_NODUP;
  55 static int option_dissociate;
  56 static int max_jobs = -1;
  57
  58 static struct option builtin_clone_options[] = {
  59         OPT__VERBOSITY(&option_verbosity),
  60         OPT_BOOL(0, "progress", &option_progress,
  61                  N_("force progress reporting")),
  62         OPT_BOOL('n', "no-checkout", &option_no_checkout,
  63                  N_("don't create a checkout")),
  64         OPT_BOOL(0, "bare", &option_bare, N_("create a bare repository")),
  65         OPT_HIDDEN_BOOL(0, "naked", &option_bare,
  66                         N_("create a bare repository")),
  67         OPT_BOOL(0, "mirror", &option_mirror,
  68                  N_("create a mirror repository (implies bare)")),
  69         OPT_BOOL('l', "local", &option_local,
  70                 N_("to clone from a local repository")),
  71         OPT_BOOL(0, "no-hardlinks", &option_no_hardlinks,
  72                     N_("don't use local hardlinks, always copy")),
  73         OPT_BOOL('s', "shared", &option_shared,
  74                     N_("setup as shared repository")),
  75         OPT_BOOL(0, "recursive", &option_recursive,
  76                     N_("initialize submodules in the clone")),
  77         OPT_BOOL(0, "recurse-submodules", &option_recursive,
  78                     N_("initialize submodules in the clone")),
  79         OPT_INTEGER('j', "jobs", &max_jobs,
  80                     N_("number of submodules cloned in parallel")),
  81         OPT_STRING(0, "template", &option_template, N_("template-directory"),
  82                    N_("directory from which templates will be used")),
  83         OPT_STRING_LIST(0, "reference", &option_required_reference, N_("repo"),
  84                         N_("reference repository")),
  85         OPT_STRING_LIST(0, "reference-if-able", &option_optional_reference,
  86                         N_("repo"), N_("reference repository")),
  87         OPT_BOOL(0, "dissociate", &option_dissociate,
  88                  N_("use --reference only while cloning")),
  89         OPT_STRING('o', "origin", &option_origin, N_("name"),
  90                    N_("use <name> instead of 'origin' to track upstream")),
  91         OPT_STRING('b', "branch", &option_branch, N_("branch"),
  92                    N_("checkout <branch> instead of the remote's HEAD")),
  93         OPT_STRING('u', "upload-pack", &option_upload_pack, N_("path"),
  94                    N_("path to git-upload-pack on the remote")),
  95         OPT_STRING(0, "depth", &option_depth, N_("depth"),
  96                     N_("create a shallow clone of that depth")),
  97         OPT_BOOL(0, "single-branch", &option_single_branch,
  98                     N_("clone only one branch, HEAD or --branch")),
  99         OPT_BOOL(0, "shallow-submodules", &option_shallow_submodules,
 100                     N_("any cloned submodules will be shallow")),
 101         OPT_STRING(0, "separate-git-dir", &real_git_dir, N_("gitdir"),
 102                    N_("separate git dir from working tree")),
 103         OPT_STRING_LIST('c', "config", &option_config, N_("key=value"),
 104                         N_("set config inside the new repository")),
 105         OPT_SET_INT('4', "ipv4", &family, N_("use IPv4 addresses only"),
 106                         TRANSPORT_FAMILY_IPV4),
 107         OPT_SET_INT('6', "ipv6", &family, N_("use IPv6 addresses only"),
 108                         TRANSPORT_FAMILY_IPV6),
 109         OPT_END()
 110 };
 111
 112 static const char *get_repo_path_1(struct strbuf *path, int *is_bundle)
 113 {
 114         static char *suffix[] = { "/.git", "", ".git/.git", ".git" };
 115         static char *bundle_suffix[] = { ".bundle", "" };
 116         size_t baselen = path->len;
 117         struct stat st;
 118         int i;
 119
 120         for (i = 0; i < ARRAY_SIZE(suffix); i++) {
 121                 strbuf_setlen(path, baselen);
 122                 strbuf_addstr(path, suffix[i]);
 123                 if (stat(path->buf, &st))
 124                         continue;
 125                 if (S_ISDIR(st.st_mode) && is_git_directory(path->buf)) {
 126                         *is_bundle = 0;
 127                         return path->buf;
 128                 } else if (S_ISREG(st.st_mode) && st.st_size > 8) {
 129                         /* Is it a "gitfile"? */
 130                         char signature[8];
 131                         const char *dst;
 132                         int len, fd = open(path->buf, O_RDONLY);
 133                         if (fd < 0)
 134                                 continue;
 135                         len = read_in_full(fd, signature, 8);
 136                         close(fd);
 137                         if (len != 8 || strncmp(signature, "gitdir: ", 8))
 138                                 continue;
 139                         dst = read_gitfile(path->buf);
 140                         if (dst) {
 141                                 *is_bundle = 0;
 142                                 return dst;
 143                         }
 144                 }
 145         }
 146
 147         for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
 148                 strbuf_setlen(path, baselen);
 149                 strbuf_addstr(path, bundle_suffix[i]);
 150                 if (!stat(path->buf, &st) && S_ISREG(st.st_mode)) {
 151                         *is_bundle = 1;
 152                         return path->buf;
 153                 }
 154         }
 155
 156         return NULL;
 157 }
 158
 159 static char *get_repo_path(const char *repo, int *is_bundle)
 160 {
 161         struct strbuf path = STRBUF_INIT;
 162         const char *raw;
 163         char *canon;
 164
 165         strbuf_addstr(&path, repo);
 166         raw = get_repo_path_1(&path, is_bundle);
 167         canon = raw ? xstrdup(absolute_path(raw)) : NULL;
 168         strbuf_release(&path);
 169         return canon;
 170 }
 171
 172 static char *guess_dir_name(const char *repo, int is_bundle, int is_bare)
 173 {
 174         const char *end = repo + strlen(repo), *start, *ptr;
 175         size_t len;
 176         char *dir;
 177
 178         /*
 179          * Skip scheme.
 180          */
 181         start = strstr(repo, "://");
 182         if (start == NULL)
 183                 start = repo;
 184         else
 185                 start += 3;
 186
 187         /*
 188          * Skip authentication data. The stripping does happen
 189          * greedily, such that we strip up to the last '@' inside
 190          * the host part.
 191          */
 192         for (ptr = start; ptr < end && !is_dir_sep(*ptr); ptr++) {
 193                 if (*ptr == '@')
 194                         start = ptr + 1;
 195         }
 196
 197         /*
 198          * Strip trailing spaces, slashes and /.git
 199          */
 200         while (start < end && (is_dir_sep(end[-1]) || isspace(end[-1])))
 201                 end--;
 202         if (end - start > 5 && is_dir_sep(end[-5]) &&
 203             !strncmp(end - 4, ".git", 4)) {
 204                 end -= 5;
 205                 while (start < end && is_dir_sep(end[-1]))
 206                         end--;
 207         }
 208
 209         /*
 210          * Strip trailing port number if we've got only a
 211          * hostname (that is, there is no dir separator but a
 212          * colon). This check is required such that we do not
 213          * strip URI's like '/foo/bar:2222.git', which should
 214          * result in a dir '2222' being guessed due to backwards
 215          * compatibility.
 216          */
 217         if (memchr(start, '/', end - start) == NULL
 218             && memchr(start, ':', end - start) != NULL) {
 219                 ptr = end;
 220                 while (start < ptr && isdigit(ptr[-1]) && ptr[-1] != ':')
 221                         ptr--;
 222                 if (start < ptr && ptr[-1] == ':')
 223                         end = ptr - 1;
 224         }
 225
 226         /*
 227          * Find last component. To remain backwards compatible we
 228          * also regard colons as path separators, such that
 229          * cloning a repository 'foo:bar.git' would result in a
 230          * directory 'bar' being guessed.
 231          */
 232         ptr = end;
 233         while (start < ptr && !is_dir_sep(ptr[-1]) && ptr[-1] != ':')
 234                 ptr--;
 235         start = ptr;
 236
 237         /*
 238          * Strip .{bundle,git}.
 239          */
 240         len = end - start;
 241         strip_suffix_mem(start, &len, is_bundle ? ".bundle" : ".git");
 242
 243         if (!len || (len == 1 && *start == '/'))
 244                 die(_("No directory name could be guessed.\n"
 245                       "Please specify a directory on the command line"));
 246
 247         if (is_bare)
 248                 dir = xstrfmt("%.*s.git", (int)len, start);
 249         else
 250                 dir = xstrndup(start, len);
 251         /*
 252          * Replace sequences of 'control' characters and whitespace
 253          * with one ascii space, remove leading and trailing spaces.
 254          */
 255         if (*dir) {
 256                 char *out = dir;
 257                 int prev_space = 1 /* strip leading whitespace */;
 258                 for (end = dir; *end; ++end) {
 259                         char ch = *end;
 260                         if ((unsigned char)ch < '\x20')
 261                                 ch = '\x20';
 262                         if (isspace(ch)) {
 263                                 if (prev_space)
 264                                         continue;
 265                                 prev_space = 1;
 266                         } else
 267                                 prev_space = 0;
 268                         *out++ = ch;
 269                 }
 270                 *out = '\0';
 271                 if (out > dir && prev_space)
 272                         out[-1] = '\0';
 273         }
 274         return dir;
 275 }
 276
 277 static void strip_trailing_slashes(char *dir)
 278 {
 279         char *end = dir + strlen(dir);
 280
 281         while (dir < end - 1 && is_dir_sep(end[-1]))
 282                 end--;
 283         *end = '\0';
 284 }
 285
 286 static int add_one_reference(struct string_list_item *item, void *cb_data)
 287 {
 288         struct strbuf err = STRBUF_INIT;
 289         int *required = cb_data;
 290         char *ref_git = compute_alternate_path(item->string, &err);
 291
 292         if (!ref_git) {
 293                 if (*required)
 294                         die("%s", err.buf);
 295                 else
 296                         fprintf(stderr,
 297                                 _("info: Could not add alternate for '%s': %s\n"),
 298                                 item->string, err.buf);
 299         } else {
 300                 struct strbuf sb = STRBUF_INIT;
 301                 strbuf_addf(&sb, "%s/objects", ref_git);
 302                 add_to_alternates_file(sb.buf);
 303                 strbuf_release(&sb);
 304         }
 305
 306         strbuf_release(&err);
 307         free(ref_git);
 308         return 0;
 309 }
 310
 311 static void setup_reference(void)
 312 {
 313         int required = 1;
 314         for_each_string_list(&option_required_reference,
 315                              add_one_reference, &required);
 316         required = 0;
 317         for_each_string_list(&option_optional_reference,
 318                              add_one_reference, &required);
 319 }
 320
 321 static void copy_alternates(struct strbuf *src, struct strbuf *dst,
 322                             const char *src_repo)
 323 {
 324         /*
 325          * Read from the source objects/info/alternates file
 326          * and copy the entries to corresponding file in the
 327          * destination repository with add_to_alternates_file().
 328          * Both src and dst have "$path/objects/info/alternates".
 329          *
 330          * Instead of copying bit-for-bit from the original,
 331          * we need to append to existing one so that the already
 332          * created entry via "clone -s" is not lost, and also
 333          * to turn entries with paths relative to the original
 334          * absolute, so that they can be used in the new repository.
 335          */
 336         FILE *in = fopen(src->buf, "r");
 337         struct strbuf line = STRBUF_INIT;
 338
 339         while (strbuf_getline(&line, in) != EOF) {
 340                 char *abs_path;
 341                 if (!line.len || line.buf[0] == '#')
 342                         continue;
 343                 if (is_absolute_path(line.buf)) {
 344                         add_to_alternates_file(line.buf);
 345                         continue;
 346                 }
 347                 abs_path = mkpathdup("%s/objects/%s", src_repo, line.buf);
 348                 normalize_path_copy(abs_path, abs_path);
 349                 add_to_alternates_file(abs_path);
 350                 free(abs_path);
 351         }
 352         strbuf_release(&line);
 353         fclose(in);
 354 }
 355
 356 static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
 357                                    const char *src_repo, int src_baselen)
 358 {
 359         struct dirent *de;
 360         struct stat buf;
 361         int src_len, dest_len;
 362         DIR *dir;
 363
 364         dir = opendir(src->buf);
 365         if (!dir)
 366                 die_errno(_("failed to open '%s'"), src->buf);
 367
 368         if (mkdir(dest->buf, 0777)) {
 369                 if (errno != EEXIST)
 370                         die_errno(_("failed to create directory '%s'"), dest->buf);
 371                 else if (stat(dest->buf, &buf))
 372                         die_errno(_("failed to stat '%s'"), dest->buf);
 373                 else if (!S_ISDIR(buf.st_mode))
 374                         die(_("%s exists and is not a directory"), dest->buf);
 375         }
 376
 377         strbuf_addch(src, '/');
 378         src_len = src->len;
 379         strbuf_addch(dest, '/');
 380         dest_len = dest->len;
 381
 382         while ((de = readdir(dir)) != NULL) {
 383                 strbuf_setlen(src, src_len);
 384                 strbuf_addstr(src, de->d_name);
 385                 strbuf_setlen(dest, dest_len);
 386                 strbuf_addstr(dest, de->d_name);
 387                 if (stat(src->buf, &buf)) {
 388                         warning (_("failed to stat %s\n"), src->buf);
 389                         continue;
 390                 }
 391                 if (S_ISDIR(buf.st_mode)) {
 392                         if (de->d_name[0] != '.')
 393                                 copy_or_link_directory(src, dest,
 394                                                        src_repo, src_baselen);
 395                         continue;
 396                 }
 397
 398                 /* Files that cannot be copied bit-for-bit... */
 399                 if (!strcmp(src->buf + src_baselen, "/info/alternates")) {
 400                         copy_alternates(src, dest, src_repo);
 401                         continue;
 402                 }
 403
 404                 if (unlink(dest->buf) && errno != ENOENT)
 405                         die_errno(_("failed to unlink '%s'"), dest->buf);
 406                 if (!option_no_hardlinks) {
 407                         if (!link(src->buf, dest->buf))
 408                                 continue;
 409                         if (option_local > 0)
 410                                 die_errno(_("failed to create link '%s'"), dest->buf);
 411                         option_no_hardlinks = 1;
 412                 }
 413                 if (copy_file_with_time(dest->buf, src->buf, 0666))
 414                         die_errno(_("failed to copy file to '%s'"), dest->buf);
 415         }
 416         closedir(dir);
 417 }
 418
 419 static void clone_local(const char *src_repo, const char *dest_repo)
 420 {
 421         if (option_shared) {
 422                 struct strbuf alt = STRBUF_INIT;
 423                 strbuf_addf(&alt, "%s/objects", src_repo);
 424                 add_to_alternates_file(alt.buf);
 425                 strbuf_release(&alt);
 426         } else {
 427                 struct strbuf src = STRBUF_INIT;
 428                 struct strbuf dest = STRBUF_INIT;
 429                 get_common_dir(&src, src_repo);
 430                 get_common_dir(&dest, dest_repo);
 431                 strbuf_addstr(&src, "/objects");
 432                 strbuf_addstr(&dest, "/objects");
 433                 copy_or_link_directory(&src, &dest, src_repo, src.len);
 434                 strbuf_release(&src);
 435                 strbuf_release(&dest);
 436         }
 437
 438         if (0 <= option_verbosity)
 439                 fprintf(stderr, _("done.\n"));
 440 }
 441
 442 static const char *junk_work_tree;
 443 static const char *junk_git_dir;
 444 static enum {
 445         JUNK_LEAVE_NONE,
 446         JUNK_LEAVE_REPO,
 447         JUNK_LEAVE_ALL
 448 } junk_mode = JUNK_LEAVE_NONE;
 449
 450 static const char junk_leave_repo_msg[] =
 451 N_("Clone succeeded, but checkout failed.\n"
 452    "You can inspect what was checked out with 'git status'\n"
 453    "and retry the checkout with 'git checkout -f HEAD'\n");
 454
 455 static void remove_junk(void)
 456 {
 457         struct strbuf sb = STRBUF_INIT;
 458
 459         switch (junk_mode) {
 460         case JUNK_LEAVE_REPO:
 461                 warning("%s", _(junk_leave_repo_msg));
 462                 /* fall-through */
 463         case JUNK_LEAVE_ALL:
 464                 return;
 465         default:
 466                 /* proceed to removal */
 467                 break;
 468         }
 469
 470         if (junk_git_dir) {
 471                 strbuf_addstr(&sb, junk_git_dir);
 472                 remove_dir_recursively(&sb, 0);
 473                 strbuf_reset(&sb);
 474         }
 475         if (junk_work_tree) {
 476                 strbuf_addstr(&sb, junk_work_tree);
 477                 remove_dir_recursively(&sb, 0);
 478                 strbuf_reset(&sb);
 479         }
 480 }
 481
 482 static void remove_junk_on_signal(int signo)
 483 {
 484         remove_junk();
 485         sigchain_pop(signo);
 486         raise(signo);
 487 }
 488
 489 static struct ref *find_remote_branch(const struct ref *refs, const char *branch)
 490 {
 491         struct ref *ref;
 492         struct strbuf head = STRBUF_INIT;
 493         strbuf_addstr(&head, "refs/heads/");
 494         strbuf_addstr(&head, branch);
 495         ref = find_ref_by_name(refs, head.buf);
 496         strbuf_release(&head);
 497
 498         if (ref)
 499                 return ref;
 500
 501         strbuf_addstr(&head, "refs/tags/");
 502         strbuf_addstr(&head, branch);
 503         ref = find_ref_by_name(refs, head.buf);
 504         strbuf_release(&head);
 505
 506         return ref;
 507 }
 508
 509 static struct ref *wanted_peer_refs(const struct ref *refs,
 510                 struct refspec *refspec)
 511 {
 512         struct ref *head = copy_ref(find_ref_by_name(refs, "HEAD"));
 513         struct ref *local_refs = head;
 514         struct ref **tail = head ? &head->next : &local_refs;
 515
 516         if (option_single_branch) {
 517                 struct ref *remote_head = NULL;
 518
 519                 if (!option_branch)
 520                         remote_head = guess_remote_head(head, refs, 0);
 521                 else {
 522                         local_refs = NULL;
 523                         tail = &local_refs;
 524                         remote_head = copy_ref(find_remote_branch(refs, option_branch));
 525                 }
 526
 527                 if (!remote_head && option_branch)
 528                         warning(_("Could not find remote branch %s to clone."),
 529                                 option_branch);
 530                 else {
 531                         get_fetch_map(remote_head, refspec, &tail, 0);
 532
 533                         /* if --branch=tag, pull the requested tag explicitly */
 534                         get_fetch_map(remote_head, tag_refspec, &tail, 0);
 535                 }
 536         } else
 537                 get_fetch_map(refs, refspec, &tail, 0);
 538
 539         if (!option_mirror && !option_single_branch)
 540                 get_fetch_map(refs, tag_refspec, &tail, 0);
 541
 542         return local_refs;
 543 }
 544
 545 static void write_remote_refs(const struct ref *local_refs)
 546 {
 547         const struct ref *r;
 548
 549         struct ref_transaction *t;
 550         struct strbuf err = STRBUF_INIT;
 551
 552         t = ref_transaction_begin(&err);
 553         if (!t)
 554                 die("%s", err.buf);
 555
 556         for (r = local_refs; r; r = r->next) {
 557                 if (!r->peer_ref)
 558                         continue;
 559                 if (ref_transaction_create(t, r->peer_ref->name, r->old_oid.hash,
 560                                            0, NULL, &err))
 561                         die("%s", err.buf);
 562         }
 563
 564         if (initial_ref_transaction_commit(t, &err))
 565                 die("%s", err.buf);
 566
 567         strbuf_release(&err);
 568         ref_transaction_free(t);
 569 }
 570
 571 static void write_followtags(const struct ref *refs, const char *msg)
 572 {
 573         const struct ref *ref;
 574         for (ref = refs; ref; ref = ref->next) {
 575                 if (!starts_with(ref->name, "refs/tags/"))
 576                         continue;
 577                 if (ends_with(ref->name, "^{}"))
 578                         continue;
 579                 if (!has_object_file(&ref->old_oid))
 580                         continue;
 581                 update_ref(msg, ref->name, ref->old_oid.hash,
 582                            NULL, 0, UPDATE_REFS_DIE_ON_ERR);
 583         }
 584 }
 585
 586 static int iterate_ref_map(void *cb_data, unsigned char sha1[20])
 587 {
 588         struct ref **rm = cb_data;
 589         struct ref *ref = *rm;
 590
 591         /*
 592          * Skip anything missing a peer_ref, which we are not
 593          * actually going to write a ref for.
 594          */
 595         while (ref && !ref->peer_ref)
 596                 ref = ref->next;
 597         /* Returning -1 notes "end of list" to the caller. */
 598         if (!ref)
 599                 return -1;
 600
 601         hashcpy(sha1, ref->old_oid.hash);
 602         *rm = ref->next;
 603         return 0;
 604 }
 605
 606 static void update_remote_refs(const struct ref *refs,
 607                                const struct ref *mapped_refs,
 608                                const struct ref *remote_head_points_at,
 609                                const char *branch_top,
 610                                const char *msg,
 611                                struct transport *transport,
 612                                int check_connectivity)
 613 {
 614         const struct ref *rm = mapped_refs;
 615
 616         if (check_connectivity) {
 617                 struct check_connected_options opt = CHECK_CONNECTED_INIT;
 618
 619                 opt.transport = transport;
 620                 opt.progress = transport->progress;
 621
 622                 if (check_connected(iterate_ref_map, &rm, &opt))
 623                         die(_("remote did not send all necessary objects"));
 624         }
 625
 626         if (refs) {
 627                 write_remote_refs(mapped_refs);
 628                 if (option_single_branch)
 629                         write_followtags(refs, msg);
 630         }
 631
 632         if (remote_head_points_at && !option_bare) {
 633                 struct strbuf head_ref = STRBUF_INIT;
 634                 strbuf_addstr(&head_ref, branch_top);
 635                 strbuf_addstr(&head_ref, "HEAD");
 636                 if (create_symref(head_ref.buf,
 637                                   remote_head_points_at->peer_ref->name,
 638                                   msg) < 0)
 639                         die(_("unable to update %s"), head_ref.buf);
 640                 strbuf_release(&head_ref);
 641         }
 642 }
 643
 644 static void update_head(const struct ref *our, const struct ref *remote,
 645                         const char *msg)
 646 {
 647         const char *head;
 648         if (our && skip_prefix(our->name, "refs/heads/", &head)) {
 649                 /* Local default branch link */
 650                 if (create_symref("HEAD", our->name, NULL) < 0)
 651                         die(_("unable to update HEAD"));
 652                 if (!option_bare) {
 653                         update_ref(msg, "HEAD", our->old_oid.hash, NULL, 0,
 654                                    UPDATE_REFS_DIE_ON_ERR);
 655                         install_branch_config(0, head, option_origin, our->name);
 656                 }
 657         } else if (our) {
 658                 struct commit *c = lookup_commit_reference(our->old_oid.hash);
 659                 /* --branch specifies a non-branch (i.e. tags), detach HEAD */
 660                 update_ref(msg, "HEAD", c->object.oid.hash,
 661                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
 662         } else if (remote) {
 663                 /*
 664                  * We know remote HEAD points to a non-branch, or
 665                  * HEAD points to a branch but we don't know which one.
 666                  * Detach HEAD in all these cases.
 667                  */
 668                 update_ref(msg, "HEAD", remote->old_oid.hash,
 669                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
 670         }
 671 }
 672
 673 static int checkout(void)
 674 {
 675         unsigned char sha1[20];
 676         char *head;
 677         struct lock_file *lock_file;
 678         struct unpack_trees_options opts;
 679         struct tree *tree;
 680         struct tree_desc t;
 681         int err = 0;
 682
 683         if (option_no_checkout)
 684                 return 0;
 685
 686         head = resolve_refdup("HEAD", RESOLVE_REF_READING, sha1, NULL);
 687         if (!head) {
 688                 warning(_("remote HEAD refers to nonexistent ref, "
 689                           "unable to checkout.\n"));
 690                 return 0;
 691         }
 692         if (!strcmp(head, "HEAD")) {
 693                 if (advice_detached_head)
 694                         detach_advice(sha1_to_hex(sha1));
 695         } else {
 696                 if (!starts_with(head, "refs/heads/"))
 697                         die(_("HEAD not found below refs/heads!"));
 698         }
 699         free(head);
 700
 701         /* We need to be in the new work tree for the checkout */
 702         setup_work_tree();
 703
 704         lock_file = xcalloc(1, sizeof(struct lock_file));
 705         hold_locked_index(lock_file, 1);
 706
 707         memset(&opts, 0, sizeof opts);
 708         opts.update = 1;
 709         opts.merge = 1;
 710         opts.fn = oneway_merge;
 711         opts.verbose_update = (option_verbosity >= 0);
 712         opts.src_index = &the_index;
 713         opts.dst_index = &the_index;
 714
 715         tree = parse_tree_indirect(sha1);
 716         parse_tree(tree);
 717         init_tree_desc(&t, tree->buffer, tree->size);
 718         if (unpack_trees(1, &t, &opts) < 0)
 719                 die(_("unable to checkout working tree"));
 720
 721         if (write_locked_index(&the_index, lock_file, COMMIT_LOCK))
 722                 die(_("unable to write new index file"));
 723
 724         err |= run_hook_le(NULL, "post-checkout", sha1_to_hex(null_sha1),
 725                            sha1_to_hex(sha1), "1", NULL);
 726
 727         if (!err && option_recursive) {
 728                 struct argv_array args = ARGV_ARRAY_INIT;
 729                 argv_array_pushl(&args, "submodule", "update", "--init", "--recursive", NULL);
 730
 731                 if (option_shallow_submodules == 1)
 732                         argv_array_push(&args, "--depth=1");
 733
 734                 if (max_jobs != -1)
 735                         argv_array_pushf(&args, "--jobs=%d", max_jobs);
 736
 737                 err = run_command_v_opt(args.argv, RUN_GIT_CMD);
 738                 argv_array_clear(&args);
 739         }
 740
 741         return err;
 742 }
 743
 744 static int write_one_config(const char *key, const char *value, void *data)
 745 {
 746         return git_config_set_multivar_gently(key, value ? value : "true", "^$", 0);
 747 }
 748
 749 static void write_config(struct string_list *config)
 750 {
 751         int i;
 752
 753         for (i = 0; i < config->nr; i++) {
 754                 if (git_config_parse_parameter(config->items[i].string,
 755                                                write_one_config, NULL) < 0)
 756                         die(_("unable to write parameters to config file"));
 757         }
 758 }
 759
 760 static void write_refspec_config(const char *src_ref_prefix,
 761                 const struct ref *our_head_points_at,
 762                 const struct ref *remote_head_points_at,
 763                 struct strbuf *branch_top)
 764 {
 765         struct strbuf key = STRBUF_INIT;
 766         struct strbuf value = STRBUF_INIT;
 767
 768         if (option_mirror || !option_bare) {
 769                 if (option_single_branch && !option_mirror) {
 770                         if (option_branch) {
 771                                 if (starts_with(our_head_points_at->name, "refs/tags/"))
 772                                         strbuf_addf(&value, "+%s:%s", our_head_points_at->name,
 773                                                 our_head_points_at->name);
 774                                 else
 775                                         strbuf_addf(&value, "+%s:%s%s", our_head_points_at->name,
 776                                                 branch_top->buf, option_branch);
 777                         } else if (remote_head_points_at) {
 778                                 const char *head = remote_head_points_at->name;
 779                                 if (!skip_prefix(head, "refs/heads/", &head))
 780                                         die("BUG: remote HEAD points at non-head?");
 781
 782                                 strbuf_addf(&value, "+%s:%s%s", remote_head_points_at->name,
 783                                                 branch_top->buf, head);
 784                         }
 785                         /*
 786                          * otherwise, the next "git fetch" will
 787                          * simply fetch from HEAD without updating
 788                          * any remote-tracking branch, which is what
 789                          * we want.
 790                          */
 791                 } else {
 792                         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top->buf);
 793                 }
 794                 /* Configure the remote */
 795                 if (value.len) {
 796                         strbuf_addf(&key, "remote.%s.fetch", option_origin);
 797                         git_config_set_multivar(key.buf, value.buf, "^$", 0);
 798                         strbuf_reset(&key);
 799
 800                         if (option_mirror) {
 801                                 strbuf_addf(&key, "remote.%s.mirror", option_origin);
 802                                 git_config_set(key.buf, "true");
 803                                 strbuf_reset(&key);
 804                         }
 805                 }
 806         }
 807
 808         strbuf_release(&key);
 809         strbuf_release(&value);
 810 }
 811
 812 static void dissociate_from_references(void)
 813 {
 814         static const char* argv[] = { "repack", "-a", "-d", NULL };
 815         char *alternates = git_pathdup("objects/info/alternates");
 816
 817         if (!access(alternates, F_OK)) {
 818                 if (run_command_v_opt(argv, RUN_GIT_CMD|RUN_COMMAND_NO_STDIN))
 819                         die(_("cannot repack to clean up"));
 820                 if (unlink(alternates) && errno != ENOENT)
 821                         die_errno(_("cannot unlink temporary alternates file"));
 822         }
 823         free(alternates);
 824 }
 825
 826 int cmd_clone(int argc, const char **argv, const char *prefix)
 827 {
 828         int is_bundle = 0, is_local;
 829         struct stat buf;
 830         const char *repo_name, *repo, *work_tree, *git_dir;
 831         char *path, *dir;
 832         int dest_exists;
 833         const struct ref *refs, *remote_head;
 834         const struct ref *remote_head_points_at;
 835         const struct ref *our_head_points_at;
 836         struct ref *mapped_refs;
 837         const struct ref *ref;
 838         struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
 839         struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
 840         struct transport *transport = NULL;
 841         const char *src_ref_prefix = "refs/heads/";
 842         struct remote *remote;
 843         int err = 0, complete_refs_before_fetch = 1;
 844
 845         struct refspec *refspec;
 846         const char *fetch_pattern;
 847
 848         packet_trace_identity("clone");
 849         argc = parse_options(argc, argv, prefix, builtin_clone_options,
 850                              builtin_clone_usage, 0);
 851
 852         if (argc > 2)
 853                 usage_msg_opt(_("Too many arguments."),
 854                         builtin_clone_usage, builtin_clone_options);
 855
 856         if (argc == 0)
 857                 usage_msg_opt(_("You must specify a repository to clone."),
 858                         builtin_clone_usage, builtin_clone_options);
 859
 860         if (option_single_branch == -1)
 861                 option_single_branch = option_depth ? 1 : 0;
 862
 863         if (option_mirror)
 864                 option_bare = 1;
 865
 866         if (option_bare) {
 867                 if (option_origin)
 868                         die(_("--bare and --origin %s options are incompatible."),
 869                             option_origin);
 870                 if (real_git_dir)
 871                         die(_("--bare and --separate-git-dir are incompatible."));
 872                 option_no_checkout = 1;
 873         }
 874
 875         if (!option_origin)
 876                 option_origin = "origin";
 877
 878         repo_name = argv[0];
 879
 880         path = get_repo_path(repo_name, &is_bundle);
 881         if (path)
 882                 repo = xstrdup(absolute_path(repo_name));
 883         else if (!strchr(repo_name, ':'))
 884                 die(_("repository '%s' does not exist"), repo_name);
 885         else
 886                 repo = repo_name;
 887
 888         /* no need to be strict, transport_set_option() will validate it again */
 889         if (option_depth && atoi(option_depth) < 1)
 890                 die(_("depth %s is not a positive number"), option_depth);
 891
 892         if (argc == 2)
 893                 dir = xstrdup(argv[1]);
 894         else
 895                 dir = guess_dir_name(repo_name, is_bundle, option_bare);
 896         strip_trailing_slashes(dir);
 897
 898         dest_exists = !stat(dir, &buf);
 899         if (dest_exists && !is_empty_dir(dir))
 900                 die(_("destination path '%s' already exists and is not "
 901                         "an empty directory."), dir);
 902
 903         strbuf_addf(&reflog_msg, "clone: from %s", repo);
 904
 905         if (option_bare)
 906                 work_tree = NULL;
 907         else {
 908                 work_tree = getenv("GIT_WORK_TREE");
 909                 if (work_tree && !stat(work_tree, &buf))
 910                         die(_("working tree '%s' already exists."), work_tree);
 911         }
 912
 913         if (option_bare || work_tree)
 914                 git_dir = xstrdup(dir);
 915         else {
 916                 work_tree = dir;
 917                 git_dir = mkpathdup("%s/.git", dir);
 918         }
 919
 920         atexit(remove_junk);
 921         sigchain_push_common(remove_junk_on_signal);
 922
 923         if (!option_bare) {
 924                 if (safe_create_leading_directories_const(work_tree) < 0)
 925                         die_errno(_("could not create leading directories of '%s'"),
 926                                   work_tree);
 927                 if (!dest_exists && mkdir(work_tree, 0777))
 928                         die_errno(_("could not create work tree dir '%s'"),
 929                                   work_tree);
 930                 junk_work_tree = work_tree;
 931                 set_git_work_tree(work_tree);
 932         }
 933
 934         junk_git_dir = git_dir;
 935         if (safe_create_leading_directories_const(git_dir) < 0)
 936                 die(_("could not create leading directories of '%s'"), git_dir);
 937
 938         set_git_dir_init(git_dir, real_git_dir, 0);
 939         if (real_git_dir) {
 940                 git_dir = real_git_dir;
 941                 junk_git_dir = real_git_dir;
 942         }
 943
 944         if (0 <= option_verbosity) {
 945                 if (option_bare)
 946                         fprintf(stderr, _("Cloning into bare repository '%s'...\n"), dir);
 947                 else
 948                         fprintf(stderr, _("Cloning into '%s'...\n"), dir);
 949         }
 950
 951         if (option_recursive) {
 952                 if (option_required_reference.nr &&
 953                     option_optional_reference.nr)
 954                         die(_("clone --recursive is not compatible with "
 955                               "both --reference and --reference-if-able"));
 956                 else if (option_required_reference.nr) {
 957                         string_list_append(&option_config,
 958                                 "submodule.alternateLocation=superproject");
 959                         string_list_append(&option_config,
 960                                 "submodule.alternateErrorStrategy=die");
 961                 } else if (option_optional_reference.nr) {
 962                         string_list_append(&option_config,
 963                                 "submodule.alternateLocation=superproject");
 964                         string_list_append(&option_config,
 965                                 "submodule.alternateErrorStrategy=info");
 966                 }
 967         }
 968
 969         init_db(option_template, INIT_DB_QUIET);
 970         write_config(&option_config);
 971
 972         git_config(git_default_config, NULL);
 973
 974         if (option_bare) {
 975                 if (option_mirror)
 976                         src_ref_prefix = "refs/";
 977                 strbuf_addstr(&branch_top, src_ref_prefix);
 978
 979                 git_config_set("core.bare", "true");
 980         } else {
 981                 strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
 982         }
 983
 984         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top.buf);
 985         strbuf_addf(&key, "remote.%s.url", option_origin);
 986         git_config_set(key.buf, repo);
 987         strbuf_reset(&key);
 988
 989         if (option_required_reference.nr || option_optional_reference.nr)
 990                 setup_reference();
 991
 992         fetch_pattern = value.buf;
 993         refspec = parse_fetch_refspec(1, &fetch_pattern);
 994
 995         strbuf_reset(&value);
 996
 997         remote = remote_get(option_origin);
 998         transport = transport_get(remote, remote->url[0]);
 999         transport_set_verbosity(transport, option_verbosity, option_progress);
1000         transport->family = family;
1001
1002         path = get_repo_path(remote->url[0], &is_bundle);
1003         is_local = option_local != 0 && path && !is_bundle;
1004         if (is_local) {
1005                 if (option_depth)
1006                         warning(_("--depth is ignored in local clones; use file:// instead."));
1007                 if (!access(mkpath("%s/shallow", path), F_OK)) {
1008                         if (option_local > 0)
1009                                 warning(_("source repository is shallow, ignoring --local"));
1010                         is_local = 0;
1011                 }
1012         }
1013         if (option_local > 0 && !is_local)
1014                 warning(_("--local is ignored"));
1015         transport->cloning = 1;
1016
1017         if (!transport->get_refs_list || (!is_local && !transport->fetch))
1018                 die(_("Don't know how to clone %s"), transport->url);
1019
1020         transport_set_option(transport, TRANS_OPT_KEEP, "yes");
1021
1022         if (option_depth)
1023                 transport_set_option(transport, TRANS_OPT_DEPTH,
1024                                      option_depth);
1025         if (option_single_branch)
1026                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
1027
1028         if (option_upload_pack)
1029                 transport_set_option(transport, TRANS_OPT_UPLOADPACK,
1030                                      option_upload_pack);
1031
1032         if (transport->smart_options && !option_depth)
1033                 transport->smart_options->check_self_contained_and_connected = 1;
1034
1035         refs = transport_get_remote_refs(transport);
1036
1037         if (refs) {
1038                 mapped_refs = wanted_peer_refs(refs, refspec);
1039                 /*
1040                  * transport_get_remote_refs() may return refs with null sha-1
1041                  * in mapped_refs (see struct transport->get_refs_list
1042                  * comment). In that case we need fetch it early because
1043                  * remote_head code below relies on it.
1044                  *
1045                  * for normal clones, transport_get_remote_refs() should
1046                  * return reliable ref set, we can delay cloning until after
1047                  * remote HEAD check.
1048                  */
1049                 for (ref = refs; ref; ref = ref->next)
1050                         if (is_null_oid(&ref->old_oid)) {
1051                                 complete_refs_before_fetch = 0;
1052                                 break;
1053                         }
1054
1055                 if (!is_local && !complete_refs_before_fetch)
1056                         transport_fetch_refs(transport, mapped_refs);
1057
1058                 remote_head = find_ref_by_name(refs, "HEAD");
1059                 remote_head_points_at =
1060                         guess_remote_head(remote_head, mapped_refs, 0);
1061
1062                 if (option_branch) {
1063                         our_head_points_at =
1064                                 find_remote_branch(mapped_refs, option_branch);
1065
1066                         if (!our_head_points_at)
1067                                 die(_("Remote branch %s not found in upstream %s"),
1068                                     option_branch, option_origin);
1069                 }
1070                 else
1071                         our_head_points_at = remote_head_points_at;
1072         }
1073         else {
1074                 if (option_branch)
1075                         die(_("Remote branch %s not found in upstream %s"),
1076                                         option_branch, option_origin);
1077
1078                 warning(_("You appear to have cloned an empty repository."));
1079                 mapped_refs = NULL;
1080                 our_head_points_at = NULL;
1081                 remote_head_points_at = NULL;
1082                 remote_head = NULL;
1083                 option_no_checkout = 1;
1084                 if (!option_bare)
1085                         install_branch_config(0, "master", option_origin,
1086                                               "refs/heads/master");
1087         }
1088
1089         write_refspec_config(src_ref_prefix, our_head_points_at,
1090                         remote_head_points_at, &branch_top);
1091
1092         if (is_local)
1093                 clone_local(path, git_dir);
1094         else if (refs && complete_refs_before_fetch)
1095                 transport_fetch_refs(transport, mapped_refs);
1096
1097         update_remote_refs(refs, mapped_refs, remote_head_points_at,
1098                            branch_top.buf, reflog_msg.buf, transport, !is_local);
1099
1100         update_head(our_head_points_at, remote_head, reflog_msg.buf);
1101
1102         transport_unlock_pack(transport);
1103         transport_disconnect(transport);
1104
1105         if (option_dissociate) {
1106                 close_all_packs();
1107                 dissociate_from_references();
1108         }
1109
1110         junk_mode = JUNK_LEAVE_REPO;
1111         err = checkout();
1112
1113         strbuf_release(&reflog_msg);
1114         strbuf_release(&branch_top);
1115         strbuf_release(&key);
1116         strbuf_release(&value);
1117         junk_mode = JUNK_LEAVE_ALL;
1118
1119         free(refspec);
1120         return err;
1121 }