git.oblomov.eu Git - git/blob - 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 struct string_list option_config;
  51 static struct string_list option_reference;
  52 static int option_dissociate;
  53
  54 static struct option builtin_clone_options[] = {
  55         OPT__VERBOSITY(&option_verbosity),
  56         OPT_BOOL(0, "progress", &option_progress,
  57                  N_("force progress reporting")),
  58         OPT_BOOL('n', "no-checkout", &option_no_checkout,
  59                  N_("don't create a checkout")),
  60         OPT_BOOL(0, "bare", &option_bare, N_("create a bare repository")),
  61         OPT_HIDDEN_BOOL(0, "naked", &option_bare,
  62                         N_("create a bare repository")),
  63         OPT_BOOL(0, "mirror", &option_mirror,
  64                  N_("create a mirror repository (implies bare)")),
  65         OPT_BOOL('l', "local", &option_local,
  66                 N_("to clone from a local repository")),
  67         OPT_BOOL(0, "no-hardlinks", &option_no_hardlinks,
  68                     N_("don't use local hardlinks, always copy")),
  69         OPT_BOOL('s', "shared", &option_shared,
  70                     N_("setup as shared repository")),
  71         OPT_BOOL(0, "recursive", &option_recursive,
  72                     N_("initialize submodules in the clone")),
  73         OPT_BOOL(0, "recurse-submodules", &option_recursive,
  74                     N_("initialize submodules in the clone")),
  75         OPT_STRING(0, "template", &option_template, N_("template-directory"),
  76                    N_("directory from which templates will be used")),
  77         OPT_STRING_LIST(0, "reference", &option_reference, N_("repo"),
  78                         N_("reference repository")),
  79         OPT_BOOL(0, "dissociate", &option_dissociate,
  80                  N_("use --reference only while cloning")),
  81         OPT_STRING('o', "origin", &option_origin, N_("name"),
  82                    N_("use <name> instead of 'origin' to track upstream")),
  83         OPT_STRING('b', "branch", &option_branch, N_("branch"),
  84                    N_("checkout <branch> instead of the remote's HEAD")),
  85         OPT_STRING('u', "upload-pack", &option_upload_pack, N_("path"),
  86                    N_("path to git-upload-pack on the remote")),
  87         OPT_STRING(0, "depth", &option_depth, N_("depth"),
  88                     N_("create a shallow clone of that depth")),
  89         OPT_BOOL(0, "single-branch", &option_single_branch,
  90                     N_("clone only one branch, HEAD or --branch")),
  91         OPT_STRING(0, "separate-git-dir", &real_git_dir, N_("gitdir"),
  92                    N_("separate git dir from working tree")),
  93         OPT_STRING_LIST('c', "config", &option_config, N_("key=value"),
  94                         N_("set config inside the new repository")),
  95         OPT_END()
  96 };
  97
  98 static const char *argv_submodule[] = {
  99         "submodule", "update", "--init", "--recursive", NULL
 100 };
 101
 102 static char *get_repo_path(const char *repo, int *is_bundle)
 103 {
 104         static char *suffix[] = { "/.git", "", ".git/.git", ".git" };
 105         static char *bundle_suffix[] = { ".bundle", "" };
 106         struct stat st;
 107         int i;
 108
 109         for (i = 0; i < ARRAY_SIZE(suffix); i++) {
 110                 const char *path;
 111                 path = mkpath("%s%s", repo, suffix[i]);
 112                 if (stat(path, &st))
 113                         continue;
 114                 if (S_ISDIR(st.st_mode) && is_git_directory(path)) {
 115                         *is_bundle = 0;
 116                         return xstrdup(absolute_path(path));
 117                 } else if (S_ISREG(st.st_mode) && st.st_size > 8) {
 118                         /* Is it a "gitfile"? */
 119                         char signature[8];
 120                         int len, fd = open(path, O_RDONLY);
 121                         if (fd < 0)
 122                                 continue;
 123                         len = read_in_full(fd, signature, 8);
 124                         close(fd);
 125                         if (len != 8 || strncmp(signature, "gitdir: ", 8))
 126                                 continue;
 127                         path = read_gitfile(path);
 128                         if (path) {
 129                                 *is_bundle = 0;
 130                                 return xstrdup(absolute_path(path));
 131                         }
 132                 }
 133         }
 134
 135         for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
 136                 const char *path;
 137                 path = mkpath("%s%s", repo, bundle_suffix[i]);
 138                 if (!stat(path, &st) && S_ISREG(st.st_mode)) {
 139                         *is_bundle = 1;
 140                         return xstrdup(absolute_path(path));
 141                 }
 142         }
 143
 144         return NULL;
 145 }
 146
 147 static char *guess_dir_name(const char *repo, int is_bundle, int is_bare)
 148 {
 149         const char *end = repo + strlen(repo), *start, *ptr;
 150         size_t len;
 151         char *dir;
 152
 153         /*
 154          * Skip scheme.
 155          */
 156         start = strstr(repo, "://");
 157         if (start == NULL)
 158                 start = repo;
 159         else
 160                 start += 3;
 161
 162         /*
 163          * Skip authentication data. The stripping does happen
 164          * greedily, such that we strip up to the last '@' inside
 165          * the host part.
 166          */
 167         for (ptr = start; ptr < end && !is_dir_sep(*ptr); ptr++) {
 168                 if (*ptr == '@')
 169                         start = ptr + 1;
 170         }
 171
 172         /*
 173          * Strip trailing spaces, slashes and /.git
 174          */
 175         while (start < end && (is_dir_sep(end[-1]) || isspace(end[-1])))
 176                 end--;
 177         if (end - start > 5 && is_dir_sep(end[-5]) &&
 178             !strncmp(end - 4, ".git", 4)) {
 179                 end -= 5;
 180                 while (start < end && is_dir_sep(end[-1]))
 181                         end--;
 182         }
 183
 184         /*
 185          * Strip trailing port number if we've got only a
 186          * hostname (that is, there is no dir separator but a
 187          * colon). This check is required such that we do not
 188          * strip URI's like '/foo/bar:2222.git', which should
 189          * result in a dir '2222' being guessed due to backwards
 190          * compatibility.
 191          */
 192         if (memchr(start, '/', end - start) == NULL
 193             && memchr(start, ':', end - start) != NULL) {
 194                 ptr = end;
 195                 while (start < ptr && isdigit(ptr[-1]) && ptr[-1] != ':')
 196                         ptr--;
 197                 if (start < ptr && ptr[-1] == ':')
 198                         end = ptr - 1;
 199         }
 200
 201         /*
 202          * Find last component. To remain backwards compatible we
 203          * also regard colons as path separators, such that
 204          * cloning a repository 'foo:bar.git' would result in a
 205          * directory 'bar' being guessed.
 206          */
 207         ptr = end;
 208         while (start < ptr && !is_dir_sep(ptr[-1]) && ptr[-1] != ':')
 209                 ptr--;
 210         start = ptr;
 211
 212         /*
 213          * Strip .{bundle,git}.
 214          */
 215         len = end - start;
 216         strip_suffix_mem(start, &len, is_bundle ? ".bundle" : ".git");
 217
 218         if (!len || (len == 1 && *start == '/'))
 219             die("No directory name could be guessed.\n"
 220                 "Please specify a directory on the command line");
 221
 222         if (is_bare)
 223                 dir = xstrfmt("%.*s.git", (int)len, start);
 224         else
 225                 dir = xstrndup(start, len);
 226         /*
 227          * Replace sequences of 'control' characters and whitespace
 228          * with one ascii space, remove leading and trailing spaces.
 229          */
 230         if (*dir) {
 231                 char *out = dir;
 232                 int prev_space = 1 /* strip leading whitespace */;
 233                 for (end = dir; *end; ++end) {
 234                         char ch = *end;
 235                         if ((unsigned char)ch < '\x20')
 236                                 ch = '\x20';
 237                         if (isspace(ch)) {
 238                                 if (prev_space)
 239                                         continue;
 240                                 prev_space = 1;
 241                         } else
 242                                 prev_space = 0;
 243                         *out++ = ch;
 244                 }
 245                 *out = '\0';
 246                 if (out > dir && prev_space)
 247                         out[-1] = '\0';
 248         }
 249         return dir;
 250 }
 251
 252 static void strip_trailing_slashes(char *dir)
 253 {
 254         char *end = dir + strlen(dir);
 255
 256         while (dir < end - 1 && is_dir_sep(end[-1]))
 257                 end--;
 258         *end = '\0';
 259 }
 260
 261 static int add_one_reference(struct string_list_item *item, void *cb_data)
 262 {
 263         char *ref_git;
 264         const char *repo;
 265         struct strbuf alternate = STRBUF_INIT;
 266
 267         /* Beware: read_gitfile(), real_path() and mkpath() return static buffer */
 268         ref_git = xstrdup(real_path(item->string));
 269
 270         repo = read_gitfile(ref_git);
 271         if (!repo)
 272                 repo = read_gitfile(mkpath("%s/.git", ref_git));
 273         if (repo) {
 274                 free(ref_git);
 275                 ref_git = xstrdup(repo);
 276         }
 277
 278         if (!repo && is_directory(mkpath("%s/.git/objects", ref_git))) {
 279                 char *ref_git_git = mkpathdup("%s/.git", ref_git);
 280                 free(ref_git);
 281                 ref_git = ref_git_git;
 282         } else if (!is_directory(mkpath("%s/objects", ref_git)))
 283                 die(_("reference repository '%s' is not a local repository."),
 284                     item->string);
 285
 286         if (!access(mkpath("%s/shallow", ref_git), F_OK))
 287                 die(_("reference repository '%s' is shallow"), item->string);
 288
 289         if (!access(mkpath("%s/info/grafts", ref_git), F_OK))
 290                 die(_("reference repository '%s' is grafted"), item->string);
 291
 292         strbuf_addf(&alternate, "%s/objects", ref_git);
 293         add_to_alternates_file(alternate.buf);
 294         strbuf_release(&alternate);
 295         free(ref_git);
 296         return 0;
 297 }
 298
 299 static void setup_reference(void)
 300 {
 301         for_each_string_list(&option_reference, add_one_reference, NULL);
 302 }
 303
 304 static void copy_alternates(struct strbuf *src, struct strbuf *dst,
 305                             const char *src_repo)
 306 {
 307         /*
 308          * Read from the source objects/info/alternates file
 309          * and copy the entries to corresponding file in the
 310          * destination repository with add_to_alternates_file().
 311          * Both src and dst have "$path/objects/info/alternates".
 312          *
 313          * Instead of copying bit-for-bit from the original,
 314          * we need to append to existing one so that the already
 315          * created entry via "clone -s" is not lost, and also
 316          * to turn entries with paths relative to the original
 317          * absolute, so that they can be used in the new repository.
 318          */
 319         FILE *in = fopen(src->buf, "r");
 320         struct strbuf line = STRBUF_INIT;
 321
 322         while (strbuf_getline(&line, in, '\n') != EOF) {
 323                 char *abs_path;
 324                 if (!line.len || line.buf[0] == '#')
 325                         continue;
 326                 if (is_absolute_path(line.buf)) {
 327                         add_to_alternates_file(line.buf);
 328                         continue;
 329                 }
 330                 abs_path = mkpathdup("%s/objects/%s", src_repo, line.buf);
 331                 normalize_path_copy(abs_path, abs_path);
 332                 add_to_alternates_file(abs_path);
 333                 free(abs_path);
 334         }
 335         strbuf_release(&line);
 336         fclose(in);
 337 }
 338
 339 static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
 340                                    const char *src_repo, int src_baselen)
 341 {
 342         struct dirent *de;
 343         struct stat buf;
 344         int src_len, dest_len;
 345         DIR *dir;
 346
 347         dir = opendir(src->buf);
 348         if (!dir)
 349                 die_errno(_("failed to open '%s'"), src->buf);
 350
 351         if (mkdir(dest->buf, 0777)) {
 352                 if (errno != EEXIST)
 353                         die_errno(_("failed to create directory '%s'"), dest->buf);
 354                 else if (stat(dest->buf, &buf))
 355                         die_errno(_("failed to stat '%s'"), dest->buf);
 356                 else if (!S_ISDIR(buf.st_mode))
 357                         die(_("%s exists and is not a directory"), dest->buf);
 358         }
 359
 360         strbuf_addch(src, '/');
 361         src_len = src->len;
 362         strbuf_addch(dest, '/');
 363         dest_len = dest->len;
 364
 365         while ((de = readdir(dir)) != NULL) {
 366                 strbuf_setlen(src, src_len);
 367                 strbuf_addstr(src, de->d_name);
 368                 strbuf_setlen(dest, dest_len);
 369                 strbuf_addstr(dest, de->d_name);
 370                 if (stat(src->buf, &buf)) {
 371                         warning (_("failed to stat %s\n"), src->buf);
 372                         continue;
 373                 }
 374                 if (S_ISDIR(buf.st_mode)) {
 375                         if (de->d_name[0] != '.')
 376                                 copy_or_link_directory(src, dest,
 377                                                        src_repo, src_baselen);
 378                         continue;
 379                 }
 380
 381                 /* Files that cannot be copied bit-for-bit... */
 382                 if (!strcmp(src->buf + src_baselen, "/info/alternates")) {
 383                         copy_alternates(src, dest, src_repo);
 384                         continue;
 385                 }
 386
 387                 if (unlink(dest->buf) && errno != ENOENT)
 388                         die_errno(_("failed to unlink '%s'"), dest->buf);
 389                 if (!option_no_hardlinks) {
 390                         if (!link(src->buf, dest->buf))
 391                                 continue;
 392                         if (option_local > 0)
 393                                 die_errno(_("failed to create link '%s'"), dest->buf);
 394                         option_no_hardlinks = 1;
 395                 }
 396                 if (copy_file_with_time(dest->buf, src->buf, 0666))
 397                         die_errno(_("failed to copy file to '%s'"), dest->buf);
 398         }
 399         closedir(dir);
 400 }
 401
 402 static void clone_local(const char *src_repo, const char *dest_repo)
 403 {
 404         if (option_shared) {
 405                 struct strbuf alt = STRBUF_INIT;
 406                 strbuf_addf(&alt, "%s/objects", src_repo);
 407                 add_to_alternates_file(alt.buf);
 408                 strbuf_release(&alt);
 409         } else {
 410                 struct strbuf src = STRBUF_INIT;
 411                 struct strbuf dest = STRBUF_INIT;
 412                 strbuf_addf(&src, "%s/objects", src_repo);
 413                 strbuf_addf(&dest, "%s/objects", dest_repo);
 414                 copy_or_link_directory(&src, &dest, src_repo, src.len);
 415                 strbuf_release(&src);
 416                 strbuf_release(&dest);
 417         }
 418
 419         if (0 <= option_verbosity)
 420                 fprintf(stderr, _("done.\n"));
 421 }
 422
 423 static const char *junk_work_tree;
 424 static const char *junk_git_dir;
 425 static enum {
 426         JUNK_LEAVE_NONE,
 427         JUNK_LEAVE_REPO,
 428         JUNK_LEAVE_ALL
 429 } junk_mode = JUNK_LEAVE_NONE;
 430
 431 static const char junk_leave_repo_msg[] =
 432 N_("Clone succeeded, but checkout failed.\n"
 433    "You can inspect what was checked out with 'git status'\n"
 434    "and retry the checkout with 'git checkout -f HEAD'\n");
 435
 436 static void remove_junk(void)
 437 {
 438         struct strbuf sb = STRBUF_INIT;
 439
 440         switch (junk_mode) {
 441         case JUNK_LEAVE_REPO:
 442                 warning("%s", _(junk_leave_repo_msg));
 443                 /* fall-through */
 444         case JUNK_LEAVE_ALL:
 445                 return;
 446         default:
 447                 /* proceed to removal */
 448                 break;
 449         }
 450
 451         if (junk_git_dir) {
 452                 strbuf_addstr(&sb, junk_git_dir);
 453                 remove_dir_recursively(&sb, 0);
 454                 strbuf_reset(&sb);
 455         }
 456         if (junk_work_tree) {
 457                 strbuf_addstr(&sb, junk_work_tree);
 458                 remove_dir_recursively(&sb, 0);
 459                 strbuf_reset(&sb);
 460         }
 461 }
 462
 463 static void remove_junk_on_signal(int signo)
 464 {
 465         remove_junk();
 466         sigchain_pop(signo);
 467         raise(signo);
 468 }
 469
 470 static struct ref *find_remote_branch(const struct ref *refs, const char *branch)
 471 {
 472         struct ref *ref;
 473         struct strbuf head = STRBUF_INIT;
 474         strbuf_addstr(&head, "refs/heads/");
 475         strbuf_addstr(&head, branch);
 476         ref = find_ref_by_name(refs, head.buf);
 477         strbuf_release(&head);
 478
 479         if (ref)
 480                 return ref;
 481
 482         strbuf_addstr(&head, "refs/tags/");
 483         strbuf_addstr(&head, branch);
 484         ref = find_ref_by_name(refs, head.buf);
 485         strbuf_release(&head);
 486
 487         return ref;
 488 }
 489
 490 static struct ref *wanted_peer_refs(const struct ref *refs,
 491                 struct refspec *refspec)
 492 {
 493         struct ref *head = copy_ref(find_ref_by_name(refs, "HEAD"));
 494         struct ref *local_refs = head;
 495         struct ref **tail = head ? &head->next : &local_refs;
 496
 497         if (option_single_branch) {
 498                 struct ref *remote_head = NULL;
 499
 500                 if (!option_branch)
 501                         remote_head = guess_remote_head(head, refs, 0);
 502                 else {
 503                         local_refs = NULL;
 504                         tail = &local_refs;
 505                         remote_head = copy_ref(find_remote_branch(refs, option_branch));
 506                 }
 507
 508                 if (!remote_head && option_branch)
 509                         warning(_("Could not find remote branch %s to clone."),
 510                                 option_branch);
 511                 else {
 512                         get_fetch_map(remote_head, refspec, &tail, 0);
 513
 514                         /* if --branch=tag, pull the requested tag explicitly */
 515                         get_fetch_map(remote_head, tag_refspec, &tail, 0);
 516                 }
 517         } else
 518                 get_fetch_map(refs, refspec, &tail, 0);
 519
 520         if (!option_mirror && !option_single_branch)
 521                 get_fetch_map(refs, tag_refspec, &tail, 0);
 522
 523         return local_refs;
 524 }
 525
 526 static void write_remote_refs(const struct ref *local_refs)
 527 {
 528         const struct ref *r;
 529
 530         struct ref_transaction *t;
 531         struct strbuf err = STRBUF_INIT;
 532
 533         t = ref_transaction_begin(&err);
 534         if (!t)
 535                 die("%s", err.buf);
 536
 537         for (r = local_refs; r; r = r->next) {
 538                 if (!r->peer_ref)
 539                         continue;
 540                 if (ref_transaction_create(t, r->peer_ref->name, r->old_sha1,
 541                                            0, NULL, &err))
 542                         die("%s", err.buf);
 543         }
 544
 545         if (initial_ref_transaction_commit(t, &err))
 546                 die("%s", err.buf);
 547
 548         strbuf_release(&err);
 549         ref_transaction_free(t);
 550 }
 551
 552 static void write_followtags(const struct ref *refs, const char *msg)
 553 {
 554         const struct ref *ref;
 555         for (ref = refs; ref; ref = ref->next) {
 556                 if (!starts_with(ref->name, "refs/tags/"))
 557                         continue;
 558                 if (ends_with(ref->name, "^{}"))
 559                         continue;
 560                 if (!has_sha1_file(ref->old_sha1))
 561                         continue;
 562                 update_ref(msg, ref->name, ref->old_sha1,
 563                            NULL, 0, UPDATE_REFS_DIE_ON_ERR);
 564         }
 565 }
 566
 567 static int iterate_ref_map(void *cb_data, unsigned char sha1[20])
 568 {
 569         struct ref **rm = cb_data;
 570         struct ref *ref = *rm;
 571
 572         /*
 573          * Skip anything missing a peer_ref, which we are not
 574          * actually going to write a ref for.
 575          */
 576         while (ref && !ref->peer_ref)
 577                 ref = ref->next;
 578         /* Returning -1 notes "end of list" to the caller. */
 579         if (!ref)
 580                 return -1;
 581
 582         hashcpy(sha1, ref->old_sha1);
 583         *rm = ref->next;
 584         return 0;
 585 }
 586
 587 static void update_remote_refs(const struct ref *refs,
 588                                const struct ref *mapped_refs,
 589                                const struct ref *remote_head_points_at,
 590                                const char *branch_top,
 591                                const char *msg,
 592                                struct transport *transport,
 593                                int check_connectivity)
 594 {
 595         const struct ref *rm = mapped_refs;
 596
 597         if (check_connectivity) {
 598                 if (transport->progress)
 599                         fprintf(stderr, _("Checking connectivity... "));
 600                 if (check_everything_connected_with_transport(iterate_ref_map,
 601                                                               0, &rm, transport))
 602                         die(_("remote did not send all necessary objects"));
 603                 if (transport->progress)
 604                         fprintf(stderr, _("done.\n"));
 605         }
 606
 607         if (refs) {
 608                 write_remote_refs(mapped_refs);
 609                 if (option_single_branch)
 610                         write_followtags(refs, msg);
 611         }
 612
 613         if (remote_head_points_at && !option_bare) {
 614                 struct strbuf head_ref = STRBUF_INIT;
 615                 strbuf_addstr(&head_ref, branch_top);
 616                 strbuf_addstr(&head_ref, "HEAD");
 617                 create_symref(head_ref.buf,
 618                               remote_head_points_at->peer_ref->name,
 619                               msg);
 620         }
 621 }
 622
 623 static void update_head(const struct ref *our, const struct ref *remote,
 624                         const char *msg)
 625 {
 626         const char *head;
 627         if (our && skip_prefix(our->name, "refs/heads/", &head)) {
 628                 /* Local default branch link */
 629                 create_symref("HEAD", our->name, NULL);
 630                 if (!option_bare) {
 631                         update_ref(msg, "HEAD", our->old_sha1, NULL, 0,
 632                                    UPDATE_REFS_DIE_ON_ERR);
 633                         install_branch_config(0, head, option_origin, our->name);
 634                 }
 635         } else if (our) {
 636                 struct commit *c = lookup_commit_reference(our->old_sha1);
 637                 /* --branch specifies a non-branch (i.e. tags), detach HEAD */
 638                 update_ref(msg, "HEAD", c->object.sha1,
 639                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
 640         } else if (remote) {
 641                 /*
 642                  * We know remote HEAD points to a non-branch, or
 643                  * HEAD points to a branch but we don't know which one.
 644                  * Detach HEAD in all these cases.
 645                  */
 646                 update_ref(msg, "HEAD", remote->old_sha1,
 647                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
 648         }
 649 }
 650
 651 static int checkout(void)
 652 {
 653         unsigned char sha1[20];
 654         char *head;
 655         struct lock_file *lock_file;
 656         struct unpack_trees_options opts;
 657         struct tree *tree;
 658         struct tree_desc t;
 659         int err = 0;
 660
 661         if (option_no_checkout)
 662                 return 0;
 663
 664         head = resolve_refdup("HEAD", RESOLVE_REF_READING, sha1, NULL);
 665         if (!head) {
 666                 warning(_("remote HEAD refers to nonexistent ref, "
 667                           "unable to checkout.\n"));
 668                 return 0;
 669         }
 670         if (!strcmp(head, "HEAD")) {
 671                 if (advice_detached_head)
 672                         detach_advice(sha1_to_hex(sha1));
 673         } else {
 674                 if (!starts_with(head, "refs/heads/"))
 675                         die(_("HEAD not found below refs/heads!"));
 676         }
 677         free(head);
 678
 679         /* We need to be in the new work tree for the checkout */
 680         setup_work_tree();
 681
 682         lock_file = xcalloc(1, sizeof(struct lock_file));
 683         hold_locked_index(lock_file, 1);
 684
 685         memset(&opts, 0, sizeof opts);
 686         opts.update = 1;
 687         opts.merge = 1;
 688         opts.fn = oneway_merge;
 689         opts.verbose_update = (option_verbosity >= 0);
 690         opts.src_index = &the_index;
 691         opts.dst_index = &the_index;
 692
 693         tree = parse_tree_indirect(sha1);
 694         parse_tree(tree);
 695         init_tree_desc(&t, tree->buffer, tree->size);
 696         if (unpack_trees(1, &t, &opts) < 0)
 697                 die(_("unable to checkout working tree"));
 698
 699         if (write_locked_index(&the_index, lock_file, COMMIT_LOCK))
 700                 die(_("unable to write new index file"));
 701
 702         err |= run_hook_le(NULL, "post-checkout", sha1_to_hex(null_sha1),
 703                            sha1_to_hex(sha1), "1", NULL);
 704
 705         if (!err && option_recursive)
 706                 err = run_command_v_opt(argv_submodule, RUN_GIT_CMD);
 707
 708         return err;
 709 }
 710
 711 static int write_one_config(const char *key, const char *value, void *data)
 712 {
 713         return git_config_set_multivar(key, value ? value : "true", "^$", 0);
 714 }
 715
 716 static void write_config(struct string_list *config)
 717 {
 718         int i;
 719
 720         for (i = 0; i < config->nr; i++) {
 721                 if (git_config_parse_parameter(config->items[i].string,
 722                                                write_one_config, NULL) < 0)
 723                         die("unable to write parameters to config file");
 724         }
 725 }
 726
 727 static void write_refspec_config(const char *src_ref_prefix,
 728                 const struct ref *our_head_points_at,
 729                 const struct ref *remote_head_points_at,
 730                 struct strbuf *branch_top)
 731 {
 732         struct strbuf key = STRBUF_INIT;
 733         struct strbuf value = STRBUF_INIT;
 734
 735         if (option_mirror || !option_bare) {
 736                 if (option_single_branch && !option_mirror) {
 737                         if (option_branch) {
 738                                 if (starts_with(our_head_points_at->name, "refs/tags/"))
 739                                         strbuf_addf(&value, "+%s:%s", our_head_points_at->name,
 740                                                 our_head_points_at->name);
 741                                 else
 742                                         strbuf_addf(&value, "+%s:%s%s", our_head_points_at->name,
 743                                                 branch_top->buf, option_branch);
 744                         } else if (remote_head_points_at) {
 745                                 const char *head = remote_head_points_at->name;
 746                                 if (!skip_prefix(head, "refs/heads/", &head))
 747                                         die("BUG: remote HEAD points at non-head?");
 748
 749                                 strbuf_addf(&value, "+%s:%s%s", remote_head_points_at->name,
 750                                                 branch_top->buf, head);
 751                         }
 752                         /*
 753                          * otherwise, the next "git fetch" will
 754                          * simply fetch from HEAD without updating
 755                          * any remote-tracking branch, which is what
 756                          * we want.
 757                          */
 758                 } else {
 759                         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top->buf);
 760                 }
 761                 /* Configure the remote */
 762                 if (value.len) {
 763                         strbuf_addf(&key, "remote.%s.fetch", option_origin);
 764                         git_config_set_multivar(key.buf, value.buf, "^$", 0);
 765                         strbuf_reset(&key);
 766
 767                         if (option_mirror) {
 768                                 strbuf_addf(&key, "remote.%s.mirror", option_origin);
 769                                 git_config_set(key.buf, "true");
 770                                 strbuf_reset(&key);
 771                         }
 772                 }
 773         }
 774
 775         strbuf_release(&key);
 776         strbuf_release(&value);
 777 }
 778
 779 static void dissociate_from_references(void)
 780 {
 781         static const char* argv[] = { "repack", "-a", "-d", NULL };
 782
 783         if (run_command_v_opt(argv, RUN_GIT_CMD|RUN_COMMAND_NO_STDIN))
 784                 die(_("cannot repack to clean up"));
 785         if (unlink(git_path("objects/info/alternates")) && errno != ENOENT)
 786                 die_errno(_("cannot unlink temporary alternates file"));
 787 }
 788
 789 int cmd_clone(int argc, const char **argv, const char *prefix)
 790 {
 791         int is_bundle = 0, is_local;
 792         struct stat buf;
 793         const char *repo_name, *repo, *work_tree, *git_dir;
 794         char *path, *dir;
 795         int dest_exists;
 796         const struct ref *refs, *remote_head;
 797         const struct ref *remote_head_points_at;
 798         const struct ref *our_head_points_at;
 799         struct ref *mapped_refs;
 800         const struct ref *ref;
 801         struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
 802         struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
 803         struct transport *transport = NULL;
 804         const char *src_ref_prefix = "refs/heads/";
 805         struct remote *remote;
 806         int err = 0, complete_refs_before_fetch = 1;
 807
 808         struct refspec *refspec;
 809         const char *fetch_pattern;
 810
 811         packet_trace_identity("clone");
 812         argc = parse_options(argc, argv, prefix, builtin_clone_options,
 813                              builtin_clone_usage, 0);
 814
 815         if (argc > 2)
 816                 usage_msg_opt(_("Too many arguments."),
 817                         builtin_clone_usage, builtin_clone_options);
 818
 819         if (argc == 0)
 820                 usage_msg_opt(_("You must specify a repository to clone."),
 821                         builtin_clone_usage, builtin_clone_options);
 822
 823         if (option_single_branch == -1)
 824                 option_single_branch = option_depth ? 1 : 0;
 825
 826         if (option_mirror)
 827                 option_bare = 1;
 828
 829         if (option_bare) {
 830                 if (option_origin)
 831                         die(_("--bare and --origin %s options are incompatible."),
 832                             option_origin);
 833                 if (real_git_dir)
 834                         die(_("--bare and --separate-git-dir are incompatible."));
 835                 option_no_checkout = 1;
 836         }
 837
 838         if (!option_origin)
 839                 option_origin = "origin";
 840
 841         repo_name = argv[0];
 842
 843         path = get_repo_path(repo_name, &is_bundle);
 844         if (path)
 845                 repo = xstrdup(absolute_path(repo_name));
 846         else if (!strchr(repo_name, ':'))
 847                 die(_("repository '%s' does not exist"), repo_name);
 848         else
 849                 repo = repo_name;
 850
 851         /* no need to be strict, transport_set_option() will validate it again */
 852         if (option_depth && atoi(option_depth) < 1)
 853                 die(_("depth %s is not a positive number"), option_depth);
 854
 855         if (argc == 2)
 856                 dir = xstrdup(argv[1]);
 857         else
 858                 dir = guess_dir_name(repo_name, is_bundle, option_bare);
 859         strip_trailing_slashes(dir);
 860
 861         dest_exists = !stat(dir, &buf);
 862         if (dest_exists && !is_empty_dir(dir))
 863                 die(_("destination path '%s' already exists and is not "
 864                         "an empty directory."), dir);
 865
 866         strbuf_addf(&reflog_msg, "clone: from %s", repo);
 867
 868         if (option_bare)
 869                 work_tree = NULL;
 870         else {
 871                 work_tree = getenv("GIT_WORK_TREE");
 872                 if (work_tree && !stat(work_tree, &buf))
 873                         die(_("working tree '%s' already exists."), work_tree);
 874         }
 875
 876         if (option_bare || work_tree)
 877                 git_dir = xstrdup(dir);
 878         else {
 879                 work_tree = dir;
 880                 git_dir = mkpathdup("%s/.git", dir);
 881         }
 882
 883         atexit(remove_junk);
 884         sigchain_push_common(remove_junk_on_signal);
 885
 886         if (!option_bare) {
 887                 if (safe_create_leading_directories_const(work_tree) < 0)
 888                         die_errno(_("could not create leading directories of '%s'"),
 889                                   work_tree);
 890                 if (!dest_exists && mkdir(work_tree, 0777))
 891                         die_errno(_("could not create work tree dir '%s'"),
 892                                   work_tree);
 893                 junk_work_tree = work_tree;
 894                 set_git_work_tree(work_tree);
 895         }
 896
 897         junk_git_dir = git_dir;
 898         if (safe_create_leading_directories_const(git_dir) < 0)
 899                 die(_("could not create leading directories of '%s'"), git_dir);
 900
 901         set_git_dir_init(git_dir, real_git_dir, 0);
 902         if (real_git_dir) {
 903                 git_dir = real_git_dir;
 904                 junk_git_dir = real_git_dir;
 905         }
 906
 907         if (0 <= option_verbosity) {
 908                 if (option_bare)
 909                         fprintf(stderr, _("Cloning into bare repository '%s'...\n"), dir);
 910                 else
 911                         fprintf(stderr, _("Cloning into '%s'...\n"), dir);
 912         }
 913         init_db(option_template, INIT_DB_QUIET);
 914         write_config(&option_config);
 915
 916         git_config(git_default_config, NULL);
 917
 918         if (option_bare) {
 919                 if (option_mirror)
 920                         src_ref_prefix = "refs/";
 921                 strbuf_addstr(&branch_top, src_ref_prefix);
 922
 923                 git_config_set("core.bare", "true");
 924         } else {
 925                 strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
 926         }
 927
 928         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top.buf);
 929         strbuf_addf(&key, "remote.%s.url", option_origin);
 930         git_config_set(key.buf, repo);
 931         strbuf_reset(&key);
 932
 933         if (option_reference.nr)
 934                 setup_reference();
 935         else if (option_dissociate) {
 936                 warning(_("--dissociate given, but there is no --reference"));
 937                 option_dissociate = 0;
 938         }
 939
 940         fetch_pattern = value.buf;
 941         refspec = parse_fetch_refspec(1, &fetch_pattern);
 942
 943         strbuf_reset(&value);
 944
 945         remote = remote_get(option_origin);
 946         transport = transport_get(remote, remote->url[0]);
 947         transport_set_verbosity(transport, option_verbosity, option_progress);
 948
 949         path = get_repo_path(remote->url[0], &is_bundle);
 950         is_local = option_local != 0 && path && !is_bundle;
 951         if (is_local) {
 952                 if (option_depth)
 953                         warning(_("--depth is ignored in local clones; use file:// instead."));
 954                 if (!access(mkpath("%s/shallow", path), F_OK)) {
 955                         if (option_local > 0)
 956                                 warning(_("source repository is shallow, ignoring --local"));
 957                         is_local = 0;
 958                 }
 959         }
 960         if (option_local > 0 && !is_local)
 961                 warning(_("--local is ignored"));
 962         transport->cloning = 1;
 963
 964         if (!transport->get_refs_list || (!is_local && !transport->fetch))
 965                 die(_("Don't know how to clone %s"), transport->url);
 966
 967         transport_set_option(transport, TRANS_OPT_KEEP, "yes");
 968
 969         if (option_depth)
 970                 transport_set_option(transport, TRANS_OPT_DEPTH,
 971                                      option_depth);
 972         if (option_single_branch)
 973                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
 974
 975         if (option_upload_pack)
 976                 transport_set_option(transport, TRANS_OPT_UPLOADPACK,
 977                                      option_upload_pack);
 978
 979         if (transport->smart_options && !option_depth)
 980                 transport->smart_options->check_self_contained_and_connected = 1;
 981
 982         refs = transport_get_remote_refs(transport);
 983
 984         if (refs) {
 985                 mapped_refs = wanted_peer_refs(refs, refspec);
 986                 /*
 987                  * transport_get_remote_refs() may return refs with null sha-1
 988                  * in mapped_refs (see struct transport->get_refs_list
 989                  * comment). In that case we need fetch it early because
 990                  * remote_head code below relies on it.
 991                  *
 992                  * for normal clones, transport_get_remote_refs() should
 993                  * return reliable ref set, we can delay cloning until after
 994                  * remote HEAD check.
 995                  */
 996                 for (ref = refs; ref; ref = ref->next)
 997                         if (is_null_sha1(ref->old_sha1)) {
 998                                 complete_refs_before_fetch = 0;
 999                                 break;
1000                         }
1001
1002                 if (!is_local && !complete_refs_before_fetch)
1003                         transport_fetch_refs(transport, mapped_refs);
1004
1005                 remote_head = find_ref_by_name(refs, "HEAD");
1006                 remote_head_points_at =
1007                         guess_remote_head(remote_head, mapped_refs, 0);
1008
1009                 if (option_branch) {
1010                         our_head_points_at =
1011                                 find_remote_branch(mapped_refs, option_branch);
1012
1013                         if (!our_head_points_at)
1014                                 die(_("Remote branch %s not found in upstream %s"),
1015                                     option_branch, option_origin);
1016                 }
1017                 else
1018                         our_head_points_at = remote_head_points_at;
1019         }
1020         else {
1021                 if (option_branch)
1022                         die(_("Remote branch %s not found in upstream %s"),
1023                                         option_branch, option_origin);
1024
1025                 warning(_("You appear to have cloned an empty repository."));
1026                 mapped_refs = NULL;
1027                 our_head_points_at = NULL;
1028                 remote_head_points_at = NULL;
1029                 remote_head = NULL;
1030                 option_no_checkout = 1;
1031                 if (!option_bare)
1032                         install_branch_config(0, "master", option_origin,
1033                                               "refs/heads/master");
1034         }
1035
1036         write_refspec_config(src_ref_prefix, our_head_points_at,
1037                         remote_head_points_at, &branch_top);
1038
1039         if (is_local)
1040                 clone_local(path, git_dir);
1041         else if (refs && complete_refs_before_fetch)
1042                 transport_fetch_refs(transport, mapped_refs);
1043
1044         update_remote_refs(refs, mapped_refs, remote_head_points_at,
1045                            branch_top.buf, reflog_msg.buf, transport, !is_local);
1046
1047         update_head(our_head_points_at, remote_head, reflog_msg.buf);
1048
1049         transport_unlock_pack(transport);
1050         transport_disconnect(transport);
1051
1052         if (option_dissociate)
1053                 dissociate_from_references();
1054
1055         junk_mode = JUNK_LEAVE_REPO;
1056         err = checkout();
1057
1058         strbuf_release(&reflog_msg);
1059         strbuf_release(&branch_top);
1060         strbuf_release(&key);
1061         strbuf_release(&value);
1062         junk_mode = JUNK_LEAVE_ALL;
1063
1064         free(refspec);
1065         return err;
1066 }