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;
 150         char *dir;
 151
 152         /*
 153          * Strip trailing spaces, slashes and /.git
 154          */
 155         while (repo < end && (is_dir_sep(end[-1]) || isspace(end[-1])))
 156                 end--;
 157         if (end - repo > 5 && is_dir_sep(end[-5]) &&
 158             !strncmp(end - 4, ".git", 4)) {
 159                 end -= 5;
 160                 while (repo < end && is_dir_sep(end[-1]))
 161                         end--;
 162         }
 163
 164         /*
 165          * Find last component, but be prepared that repo could have
 166          * the form  "remote.example.com:foo.git", i.e. no slash
 167          * in the directory part.
 168          */
 169         start = end;
 170         while (repo < start && !is_dir_sep(start[-1]) && start[-1] != ':')
 171                 start--;
 172
 173         /*
 174          * Strip .{bundle,git}.
 175          */
 176         if (is_bundle) {
 177                 if (end - start > 7 && !strncmp(end - 7, ".bundle", 7))
 178                         end -= 7;
 179         } else {
 180                 if (end - start > 4 && !strncmp(end - 4, ".git", 4))
 181                         end -= 4;
 182         }
 183
 184         if (is_bare) {
 185                 struct strbuf result = STRBUF_INIT;
 186                 strbuf_addf(&result, "%.*s.git", (int)(end - start), start);
 187                 dir = strbuf_detach(&result, NULL);
 188         } else
 189                 dir = xstrndup(start, end - start);
 190         /*
 191          * Replace sequences of 'control' characters and whitespace
 192          * with one ascii space, remove leading and trailing spaces.
 193          */
 194         if (*dir) {
 195                 char *out = dir;
 196                 int prev_space = 1 /* strip leading whitespace */;
 197                 for (end = dir; *end; ++end) {
 198                         char ch = *end;
 199                         if ((unsigned char)ch < '\x20')
 200                                 ch = '\x20';
 201                         if (isspace(ch)) {
 202                                 if (prev_space)
 203                                         continue;
 204                                 prev_space = 1;
 205                         } else
 206                                 prev_space = 0;
 207                         *out++ = ch;
 208                 }
 209                 *out = '\0';
 210                 if (out > dir && prev_space)
 211                         out[-1] = '\0';
 212         }
 213         return dir;
 214 }
 215
 216 static void strip_trailing_slashes(char *dir)
 217 {
 218         char *end = dir + strlen(dir);
 219
 220         while (dir < end - 1 && is_dir_sep(end[-1]))
 221                 end--;
 222         *end = '\0';
 223 }
 224
 225 static int add_one_reference(struct string_list_item *item, void *cb_data)
 226 {
 227         char *ref_git;
 228         const char *repo;
 229         struct strbuf alternate = STRBUF_INIT;
 230
 231         /* Beware: read_gitfile(), real_path() and mkpath() return static buffer */
 232         ref_git = xstrdup(real_path(item->string));
 233
 234         repo = read_gitfile(ref_git);
 235         if (!repo)
 236                 repo = read_gitfile(mkpath("%s/.git", ref_git));
 237         if (repo) {
 238                 free(ref_git);
 239                 ref_git = xstrdup(repo);
 240         }
 241
 242         if (!repo && is_directory(mkpath("%s/.git/objects", ref_git))) {
 243                 char *ref_git_git = mkpathdup("%s/.git", ref_git);
 244                 free(ref_git);
 245                 ref_git = ref_git_git;
 246         } else if (!is_directory(mkpath("%s/objects", ref_git)))
 247                 die(_("reference repository '%s' is not a local repository."),
 248                     item->string);
 249
 250         if (!access(mkpath("%s/shallow", ref_git), F_OK))
 251                 die(_("reference repository '%s' is shallow"), item->string);
 252
 253         if (!access(mkpath("%s/info/grafts", ref_git), F_OK))
 254                 die(_("reference repository '%s' is grafted"), item->string);
 255
 256         strbuf_addf(&alternate, "%s/objects", ref_git);
 257         add_to_alternates_file(alternate.buf);
 258         strbuf_release(&alternate);
 259         free(ref_git);
 260         return 0;
 261 }
 262
 263 static void setup_reference(void)
 264 {
 265         for_each_string_list(&option_reference, add_one_reference, NULL);
 266 }
 267
 268 static void copy_alternates(struct strbuf *src, struct strbuf *dst,
 269                             const char *src_repo)
 270 {
 271         /*
 272          * Read from the source objects/info/alternates file
 273          * and copy the entries to corresponding file in the
 274          * destination repository with add_to_alternates_file().
 275          * Both src and dst have "$path/objects/info/alternates".
 276          *
 277          * Instead of copying bit-for-bit from the original,
 278          * we need to append to existing one so that the already
 279          * created entry via "clone -s" is not lost, and also
 280          * to turn entries with paths relative to the original
 281          * absolute, so that they can be used in the new repository.
 282          */
 283         FILE *in = fopen(src->buf, "r");
 284         struct strbuf line = STRBUF_INIT;
 285
 286         while (strbuf_getline(&line, in, '\n') != EOF) {
 287                 char *abs_path;
 288                 if (!line.len || line.buf[0] == '#')
 289                         continue;
 290                 if (is_absolute_path(line.buf)) {
 291                         add_to_alternates_file(line.buf);
 292                         continue;
 293                 }
 294                 abs_path = mkpathdup("%s/objects/%s", src_repo, line.buf);
 295                 normalize_path_copy(abs_path, abs_path);
 296                 add_to_alternates_file(abs_path);
 297                 free(abs_path);
 298         }
 299         strbuf_release(&line);
 300         fclose(in);
 301 }
 302
 303 static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
 304                                    const char *src_repo, int src_baselen)
 305 {
 306         struct dirent *de;
 307         struct stat buf;
 308         int src_len, dest_len;
 309         DIR *dir;
 310
 311         dir = opendir(src->buf);
 312         if (!dir)
 313                 die_errno(_("failed to open '%s'"), src->buf);
 314
 315         if (mkdir(dest->buf, 0777)) {
 316                 if (errno != EEXIST)
 317                         die_errno(_("failed to create directory '%s'"), dest->buf);
 318                 else if (stat(dest->buf, &buf))
 319                         die_errno(_("failed to stat '%s'"), dest->buf);
 320                 else if (!S_ISDIR(buf.st_mode))
 321                         die(_("%s exists and is not a directory"), dest->buf);
 322         }
 323
 324         strbuf_addch(src, '/');
 325         src_len = src->len;
 326         strbuf_addch(dest, '/');
 327         dest_len = dest->len;
 328
 329         while ((de = readdir(dir)) != NULL) {
 330                 strbuf_setlen(src, src_len);
 331                 strbuf_addstr(src, de->d_name);
 332                 strbuf_setlen(dest, dest_len);
 333                 strbuf_addstr(dest, de->d_name);
 334                 if (stat(src->buf, &buf)) {
 335                         warning (_("failed to stat %s\n"), src->buf);
 336                         continue;
 337                 }
 338                 if (S_ISDIR(buf.st_mode)) {
 339                         if (de->d_name[0] != '.')
 340                                 copy_or_link_directory(src, dest,
 341                                                        src_repo, src_baselen);
 342                         continue;
 343                 }
 344
 345                 /* Files that cannot be copied bit-for-bit... */
 346                 if (!strcmp(src->buf + src_baselen, "/info/alternates")) {
 347                         copy_alternates(src, dest, src_repo);
 348                         continue;
 349                 }
 350
 351                 if (unlink(dest->buf) && errno != ENOENT)
 352                         die_errno(_("failed to unlink '%s'"), dest->buf);
 353                 if (!option_no_hardlinks) {
 354                         if (!link(src->buf, dest->buf))
 355                                 continue;
 356                         if (option_local > 0)
 357                                 die_errno(_("failed to create link '%s'"), dest->buf);
 358                         option_no_hardlinks = 1;
 359                 }
 360                 if (copy_file_with_time(dest->buf, src->buf, 0666))
 361                         die_errno(_("failed to copy file to '%s'"), dest->buf);
 362         }
 363         closedir(dir);
 364 }
 365
 366 static void clone_local(const char *src_repo, const char *dest_repo)
 367 {
 368         if (option_shared) {
 369                 struct strbuf alt = STRBUF_INIT;
 370                 strbuf_addf(&alt, "%s/objects", src_repo);
 371                 add_to_alternates_file(alt.buf);
 372                 strbuf_release(&alt);
 373         } else {
 374                 struct strbuf src = STRBUF_INIT;
 375                 struct strbuf dest = STRBUF_INIT;
 376                 strbuf_addf(&src, "%s/objects", src_repo);
 377                 strbuf_addf(&dest, "%s/objects", dest_repo);
 378                 copy_or_link_directory(&src, &dest, src_repo, src.len);
 379                 strbuf_release(&src);
 380                 strbuf_release(&dest);
 381         }
 382
 383         if (0 <= option_verbosity)
 384                 fprintf(stderr, _("done.\n"));
 385 }
 386
 387 static const char *junk_work_tree;
 388 static const char *junk_git_dir;
 389 static enum {
 390         JUNK_LEAVE_NONE,
 391         JUNK_LEAVE_REPO,
 392         JUNK_LEAVE_ALL
 393 } junk_mode = JUNK_LEAVE_NONE;
 394
 395 static const char junk_leave_repo_msg[] =
 396 N_("Clone succeeded, but checkout failed.\n"
 397    "You can inspect what was checked out with 'git status'\n"
 398    "and retry the checkout with 'git checkout -f HEAD'\n");
 399
 400 static void remove_junk(void)
 401 {
 402         struct strbuf sb = STRBUF_INIT;
 403
 404         switch (junk_mode) {
 405         case JUNK_LEAVE_REPO:
 406                 warning("%s", _(junk_leave_repo_msg));
 407                 /* fall-through */
 408         case JUNK_LEAVE_ALL:
 409                 return;
 410         default:
 411                 /* proceed to removal */
 412                 break;
 413         }
 414
 415         if (junk_git_dir) {
 416                 strbuf_addstr(&sb, junk_git_dir);
 417                 remove_dir_recursively(&sb, 0);
 418                 strbuf_reset(&sb);
 419         }
 420         if (junk_work_tree) {
 421                 strbuf_addstr(&sb, junk_work_tree);
 422                 remove_dir_recursively(&sb, 0);
 423                 strbuf_reset(&sb);
 424         }
 425 }
 426
 427 static void remove_junk_on_signal(int signo)
 428 {
 429         remove_junk();
 430         sigchain_pop(signo);
 431         raise(signo);
 432 }
 433
 434 static struct ref *find_remote_branch(const struct ref *refs, const char *branch)
 435 {
 436         struct ref *ref;
 437         struct strbuf head = STRBUF_INIT;
 438         strbuf_addstr(&head, "refs/heads/");
 439         strbuf_addstr(&head, branch);
 440         ref = find_ref_by_name(refs, head.buf);
 441         strbuf_release(&head);
 442
 443         if (ref)
 444                 return ref;
 445
 446         strbuf_addstr(&head, "refs/tags/");
 447         strbuf_addstr(&head, branch);
 448         ref = find_ref_by_name(refs, head.buf);
 449         strbuf_release(&head);
 450
 451         return ref;
 452 }
 453
 454 static struct ref *wanted_peer_refs(const struct ref *refs,
 455                 struct refspec *refspec)
 456 {
 457         struct ref *head = copy_ref(find_ref_by_name(refs, "HEAD"));
 458         struct ref *local_refs = head;
 459         struct ref **tail = head ? &head->next : &local_refs;
 460
 461         if (option_single_branch) {
 462                 struct ref *remote_head = NULL;
 463
 464                 if (!option_branch)
 465                         remote_head = guess_remote_head(head, refs, 0);
 466                 else {
 467                         local_refs = NULL;
 468                         tail = &local_refs;
 469                         remote_head = copy_ref(find_remote_branch(refs, option_branch));
 470                 }
 471
 472                 if (!remote_head && option_branch)
 473                         warning(_("Could not find remote branch %s to clone."),
 474                                 option_branch);
 475                 else {
 476                         get_fetch_map(remote_head, refspec, &tail, 0);
 477
 478                         /* if --branch=tag, pull the requested tag explicitly */
 479                         get_fetch_map(remote_head, tag_refspec, &tail, 0);
 480                 }
 481         } else
 482                 get_fetch_map(refs, refspec, &tail, 0);
 483
 484         if (!option_mirror && !option_single_branch)
 485                 get_fetch_map(refs, tag_refspec, &tail, 0);
 486
 487         return local_refs;
 488 }
 489
 490 static void write_remote_refs(const struct ref *local_refs)
 491 {
 492         const struct ref *r;
 493
 494         struct ref_transaction *t;
 495         struct strbuf err = STRBUF_INIT;
 496
 497         t = ref_transaction_begin(&err);
 498         if (!t)
 499                 die("%s", err.buf);
 500
 501         for (r = local_refs; r; r = r->next) {
 502                 if (!r->peer_ref)
 503                         continue;
 504                 if (ref_transaction_create(t, r->peer_ref->name, r->old_sha1,
 505                                            0, NULL, &err))
 506                         die("%s", err.buf);
 507         }
 508
 509         if (initial_ref_transaction_commit(t, &err))
 510                 die("%s", err.buf);
 511
 512         strbuf_release(&err);
 513         ref_transaction_free(t);
 514 }
 515
 516 static void write_followtags(const struct ref *refs, const char *msg)
 517 {
 518         const struct ref *ref;
 519         for (ref = refs; ref; ref = ref->next) {
 520                 if (!starts_with(ref->name, "refs/tags/"))
 521                         continue;
 522                 if (ends_with(ref->name, "^{}"))
 523                         continue;
 524                 if (!has_sha1_file(ref->old_sha1))
 525                         continue;
 526                 update_ref(msg, ref->name, ref->old_sha1,
 527                            NULL, 0, UPDATE_REFS_DIE_ON_ERR);
 528         }
 529 }
 530
 531 static int iterate_ref_map(void *cb_data, unsigned char sha1[20])
 532 {
 533         struct ref **rm = cb_data;
 534         struct ref *ref = *rm;
 535
 536         /*
 537          * Skip anything missing a peer_ref, which we are not
 538          * actually going to write a ref for.
 539          */
 540         while (ref && !ref->peer_ref)
 541                 ref = ref->next;
 542         /* Returning -1 notes "end of list" to the caller. */
 543         if (!ref)
 544                 return -1;
 545
 546         hashcpy(sha1, ref->old_sha1);
 547         *rm = ref->next;
 548         return 0;
 549 }
 550
 551 static void update_remote_refs(const struct ref *refs,
 552                                const struct ref *mapped_refs,
 553                                const struct ref *remote_head_points_at,
 554                                const char *branch_top,
 555                                const char *msg,
 556                                struct transport *transport,
 557                                int check_connectivity)
 558 {
 559         const struct ref *rm = mapped_refs;
 560
 561         if (check_connectivity) {
 562                 if (transport->progress)
 563                         fprintf(stderr, _("Checking connectivity... "));
 564                 if (check_everything_connected_with_transport(iterate_ref_map,
 565                                                               0, &rm, transport))
 566                         die(_("remote did not send all necessary objects"));
 567                 if (transport->progress)
 568                         fprintf(stderr, _("done.\n"));
 569         }
 570
 571         if (refs) {
 572                 write_remote_refs(mapped_refs);
 573                 if (option_single_branch)
 574                         write_followtags(refs, msg);
 575         }
 576
 577         if (remote_head_points_at && !option_bare) {
 578                 struct strbuf head_ref = STRBUF_INIT;
 579                 strbuf_addstr(&head_ref, branch_top);
 580                 strbuf_addstr(&head_ref, "HEAD");
 581                 create_symref(head_ref.buf,
 582                               remote_head_points_at->peer_ref->name,
 583                               msg);
 584         }
 585 }
 586
 587 static void update_head(const struct ref *our, const struct ref *remote,
 588                         const char *msg)
 589 {
 590         const char *head;
 591         if (our && skip_prefix(our->name, "refs/heads/", &head)) {
 592                 /* Local default branch link */
 593                 create_symref("HEAD", our->name, NULL);
 594                 if (!option_bare) {
 595                         update_ref(msg, "HEAD", our->old_sha1, NULL, 0,
 596                                    UPDATE_REFS_DIE_ON_ERR);
 597                         install_branch_config(0, head, option_origin, our->name);
 598                 }
 599         } else if (our) {
 600                 struct commit *c = lookup_commit_reference(our->old_sha1);
 601                 /* --branch specifies a non-branch (i.e. tags), detach HEAD */
 602                 update_ref(msg, "HEAD", c->object.sha1,
 603                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
 604         } else if (remote) {
 605                 /*
 606                  * We know remote HEAD points to a non-branch, or
 607                  * HEAD points to a branch but we don't know which one.
 608                  * Detach HEAD in all these cases.
 609                  */
 610                 update_ref(msg, "HEAD", remote->old_sha1,
 611                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
 612         }
 613 }
 614
 615 static int checkout(void)
 616 {
 617         unsigned char sha1[20];
 618         char *head;
 619         struct lock_file *lock_file;
 620         struct unpack_trees_options opts;
 621         struct tree *tree;
 622         struct tree_desc t;
 623         int err = 0;
 624
 625         if (option_no_checkout)
 626                 return 0;
 627
 628         head = resolve_refdup("HEAD", RESOLVE_REF_READING, sha1, NULL);
 629         if (!head) {
 630                 warning(_("remote HEAD refers to nonexistent ref, "
 631                           "unable to checkout.\n"));
 632                 return 0;
 633         }
 634         if (!strcmp(head, "HEAD")) {
 635                 if (advice_detached_head)
 636                         detach_advice(sha1_to_hex(sha1));
 637         } else {
 638                 if (!starts_with(head, "refs/heads/"))
 639                         die(_("HEAD not found below refs/heads!"));
 640         }
 641         free(head);
 642
 643         /* We need to be in the new work tree for the checkout */
 644         setup_work_tree();
 645
 646         lock_file = xcalloc(1, sizeof(struct lock_file));
 647         hold_locked_index(lock_file, 1);
 648
 649         memset(&opts, 0, sizeof opts);
 650         opts.update = 1;
 651         opts.merge = 1;
 652         opts.fn = oneway_merge;
 653         opts.verbose_update = (option_verbosity >= 0);
 654         opts.src_index = &the_index;
 655         opts.dst_index = &the_index;
 656
 657         tree = parse_tree_indirect(sha1);
 658         parse_tree(tree);
 659         init_tree_desc(&t, tree->buffer, tree->size);
 660         if (unpack_trees(1, &t, &opts) < 0)
 661                 die(_("unable to checkout working tree"));
 662
 663         if (write_locked_index(&the_index, lock_file, COMMIT_LOCK))
 664                 die(_("unable to write new index file"));
 665
 666         err |= run_hook_le(NULL, "post-checkout", sha1_to_hex(null_sha1),
 667                            sha1_to_hex(sha1), "1", NULL);
 668
 669         if (!err && option_recursive)
 670                 err = run_command_v_opt(argv_submodule, RUN_GIT_CMD);
 671
 672         return err;
 673 }
 674
 675 static int write_one_config(const char *key, const char *value, void *data)
 676 {
 677         return git_config_set_multivar(key, value ? value : "true", "^$", 0);
 678 }
 679
 680 static void write_config(struct string_list *config)
 681 {
 682         int i;
 683
 684         for (i = 0; i < config->nr; i++) {
 685                 if (git_config_parse_parameter(config->items[i].string,
 686                                                write_one_config, NULL) < 0)
 687                         die("unable to write parameters to config file");
 688         }
 689 }
 690
 691 static void write_refspec_config(const char *src_ref_prefix,
 692                 const struct ref *our_head_points_at,
 693                 const struct ref *remote_head_points_at,
 694                 struct strbuf *branch_top)
 695 {
 696         struct strbuf key = STRBUF_INIT;
 697         struct strbuf value = STRBUF_INIT;
 698
 699         if (option_mirror || !option_bare) {
 700                 if (option_single_branch && !option_mirror) {
 701                         if (option_branch) {
 702                                 if (starts_with(our_head_points_at->name, "refs/tags/"))
 703                                         strbuf_addf(&value, "+%s:%s", our_head_points_at->name,
 704                                                 our_head_points_at->name);
 705                                 else
 706                                         strbuf_addf(&value, "+%s:%s%s", our_head_points_at->name,
 707                                                 branch_top->buf, option_branch);
 708                         } else if (remote_head_points_at) {
 709                                 const char *head = remote_head_points_at->name;
 710                                 if (!skip_prefix(head, "refs/heads/", &head))
 711                                         die("BUG: remote HEAD points at non-head?");
 712
 713                                 strbuf_addf(&value, "+%s:%s%s", remote_head_points_at->name,
 714                                                 branch_top->buf, head);
 715                         }
 716                         /*
 717                          * otherwise, the next "git fetch" will
 718                          * simply fetch from HEAD without updating
 719                          * any remote-tracking branch, which is what
 720                          * we want.
 721                          */
 722                 } else {
 723                         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top->buf);
 724                 }
 725                 /* Configure the remote */
 726                 if (value.len) {
 727                         strbuf_addf(&key, "remote.%s.fetch", option_origin);
 728                         git_config_set_multivar(key.buf, value.buf, "^$", 0);
 729                         strbuf_reset(&key);
 730
 731                         if (option_mirror) {
 732                                 strbuf_addf(&key, "remote.%s.mirror", option_origin);
 733                                 git_config_set(key.buf, "true");
 734                                 strbuf_reset(&key);
 735                         }
 736                 }
 737         }
 738
 739         strbuf_release(&key);
 740         strbuf_release(&value);
 741 }
 742
 743 static void dissociate_from_references(void)
 744 {
 745         static const char* argv[] = { "repack", "-a", "-d", NULL };
 746
 747         if (run_command_v_opt(argv, RUN_GIT_CMD|RUN_COMMAND_NO_STDIN))
 748                 die(_("cannot repack to clean up"));
 749         if (unlink(git_path("objects/info/alternates")) && errno != ENOENT)
 750                 die_errno(_("cannot unlink temporary alternates file"));
 751 }
 752
 753 int cmd_clone(int argc, const char **argv, const char *prefix)
 754 {
 755         int is_bundle = 0, is_local;
 756         struct stat buf;
 757         const char *repo_name, *repo, *work_tree, *git_dir;
 758         char *path, *dir;
 759         int dest_exists;
 760         const struct ref *refs, *remote_head;
 761         const struct ref *remote_head_points_at;
 762         const struct ref *our_head_points_at;
 763         struct ref *mapped_refs;
 764         const struct ref *ref;
 765         struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
 766         struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
 767         struct transport *transport = NULL;
 768         const char *src_ref_prefix = "refs/heads/";
 769         struct remote *remote;
 770         int err = 0, complete_refs_before_fetch = 1;
 771
 772         struct refspec *refspec;
 773         const char *fetch_pattern;
 774
 775         packet_trace_identity("clone");
 776         argc = parse_options(argc, argv, prefix, builtin_clone_options,
 777                              builtin_clone_usage, 0);
 778
 779         if (argc > 2)
 780                 usage_msg_opt(_("Too many arguments."),
 781                         builtin_clone_usage, builtin_clone_options);
 782
 783         if (argc == 0)
 784                 usage_msg_opt(_("You must specify a repository to clone."),
 785                         builtin_clone_usage, builtin_clone_options);
 786
 787         if (option_single_branch == -1)
 788                 option_single_branch = option_depth ? 1 : 0;
 789
 790         if (option_mirror)
 791                 option_bare = 1;
 792
 793         if (option_bare) {
 794                 if (option_origin)
 795                         die(_("--bare and --origin %s options are incompatible."),
 796                             option_origin);
 797                 if (real_git_dir)
 798                         die(_("--bare and --separate-git-dir are incompatible."));
 799                 option_no_checkout = 1;
 800         }
 801
 802         if (!option_origin)
 803                 option_origin = "origin";
 804
 805         repo_name = argv[0];
 806
 807         path = get_repo_path(repo_name, &is_bundle);
 808         if (path)
 809                 repo = xstrdup(absolute_path(repo_name));
 810         else if (!strchr(repo_name, ':'))
 811                 die(_("repository '%s' does not exist"), repo_name);
 812         else
 813                 repo = repo_name;
 814
 815         /* no need to be strict, transport_set_option() will validate it again */
 816         if (option_depth && atoi(option_depth) < 1)
 817                 die(_("depth %s is not a positive number"), option_depth);
 818
 819         if (argc == 2)
 820                 dir = xstrdup(argv[1]);
 821         else
 822                 dir = guess_dir_name(repo_name, is_bundle, option_bare);
 823         strip_trailing_slashes(dir);
 824
 825         dest_exists = !stat(dir, &buf);
 826         if (dest_exists && !is_empty_dir(dir))
 827                 die(_("destination path '%s' already exists and is not "
 828                         "an empty directory."), dir);
 829
 830         strbuf_addf(&reflog_msg, "clone: from %s", repo);
 831
 832         if (option_bare)
 833                 work_tree = NULL;
 834         else {
 835                 work_tree = getenv("GIT_WORK_TREE");
 836                 if (work_tree && !stat(work_tree, &buf))
 837                         die(_("working tree '%s' already exists."), work_tree);
 838         }
 839
 840         if (option_bare || work_tree)
 841                 git_dir = xstrdup(dir);
 842         else {
 843                 work_tree = dir;
 844                 git_dir = mkpathdup("%s/.git", dir);
 845         }
 846
 847         atexit(remove_junk);
 848         sigchain_push_common(remove_junk_on_signal);
 849
 850         if (!option_bare) {
 851                 if (safe_create_leading_directories_const(work_tree) < 0)
 852                         die_errno(_("could not create leading directories of '%s'"),
 853                                   work_tree);
 854                 if (!dest_exists && mkdir(work_tree, 0777))
 855                         die_errno(_("could not create work tree dir '%s'"),
 856                                   work_tree);
 857                 junk_work_tree = work_tree;
 858                 set_git_work_tree(work_tree);
 859         }
 860
 861         junk_git_dir = git_dir;
 862         if (safe_create_leading_directories_const(git_dir) < 0)
 863                 die(_("could not create leading directories of '%s'"), git_dir);
 864
 865         set_git_dir_init(git_dir, real_git_dir, 0);
 866         if (real_git_dir) {
 867                 git_dir = real_git_dir;
 868                 junk_git_dir = real_git_dir;
 869         }
 870
 871         if (0 <= option_verbosity) {
 872                 if (option_bare)
 873                         fprintf(stderr, _("Cloning into bare repository '%s'...\n"), dir);
 874                 else
 875                         fprintf(stderr, _("Cloning into '%s'...\n"), dir);
 876         }
 877         init_db(option_template, INIT_DB_QUIET);
 878         write_config(&option_config);
 879
 880         git_config(git_default_config, NULL);
 881
 882         if (option_bare) {
 883                 if (option_mirror)
 884                         src_ref_prefix = "refs/";
 885                 strbuf_addstr(&branch_top, src_ref_prefix);
 886
 887                 git_config_set("core.bare", "true");
 888         } else {
 889                 strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
 890         }
 891
 892         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top.buf);
 893         strbuf_addf(&key, "remote.%s.url", option_origin);
 894         git_config_set(key.buf, repo);
 895         strbuf_reset(&key);
 896
 897         if (option_reference.nr)
 898                 setup_reference();
 899         else if (option_dissociate) {
 900                 warning(_("--dissociate given, but there is no --reference"));
 901                 option_dissociate = 0;
 902         }
 903
 904         fetch_pattern = value.buf;
 905         refspec = parse_fetch_refspec(1, &fetch_pattern);
 906
 907         strbuf_reset(&value);
 908
 909         remote = remote_get(option_origin);
 910         transport = transport_get(remote, remote->url[0]);
 911         transport_set_verbosity(transport, option_verbosity, option_progress);
 912
 913         path = get_repo_path(remote->url[0], &is_bundle);
 914         is_local = option_local != 0 && path && !is_bundle;
 915         if (is_local) {
 916                 if (option_depth)
 917                         warning(_("--depth is ignored in local clones; use file:// instead."));
 918                 if (!access(mkpath("%s/shallow", path), F_OK)) {
 919                         if (option_local > 0)
 920                                 warning(_("source repository is shallow, ignoring --local"));
 921                         is_local = 0;
 922                 }
 923         }
 924         if (option_local > 0 && !is_local)
 925                 warning(_("--local is ignored"));
 926         transport->cloning = 1;
 927
 928         if (!transport->get_refs_list || (!is_local && !transport->fetch))
 929                 die(_("Don't know how to clone %s"), transport->url);
 930
 931         transport_set_option(transport, TRANS_OPT_KEEP, "yes");
 932
 933         if (option_depth)
 934                 transport_set_option(transport, TRANS_OPT_DEPTH,
 935                                      option_depth);
 936         if (option_single_branch)
 937                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
 938
 939         if (option_upload_pack)
 940                 transport_set_option(transport, TRANS_OPT_UPLOADPACK,
 941                                      option_upload_pack);
 942
 943         if (transport->smart_options && !option_depth)
 944                 transport->smart_options->check_self_contained_and_connected = 1;
 945
 946         refs = transport_get_remote_refs(transport);
 947
 948         if (refs) {
 949                 mapped_refs = wanted_peer_refs(refs, refspec);
 950                 /*
 951                  * transport_get_remote_refs() may return refs with null sha-1
 952                  * in mapped_refs (see struct transport->get_refs_list
 953                  * comment). In that case we need fetch it early because
 954                  * remote_head code below relies on it.
 955                  *
 956                  * for normal clones, transport_get_remote_refs() should
 957                  * return reliable ref set, we can delay cloning until after
 958                  * remote HEAD check.
 959                  */
 960                 for (ref = refs; ref; ref = ref->next)
 961                         if (is_null_sha1(ref->old_sha1)) {
 962                                 complete_refs_before_fetch = 0;
 963                                 break;
 964                         }
 965
 966                 if (!is_local && !complete_refs_before_fetch)
 967                         transport_fetch_refs(transport, mapped_refs);
 968
 969                 remote_head = find_ref_by_name(refs, "HEAD");
 970                 remote_head_points_at =
 971                         guess_remote_head(remote_head, mapped_refs, 0);
 972
 973                 if (option_branch) {
 974                         our_head_points_at =
 975                                 find_remote_branch(mapped_refs, option_branch);
 976
 977                         if (!our_head_points_at)
 978                                 die(_("Remote branch %s not found in upstream %s"),
 979                                     option_branch, option_origin);
 980                 }
 981                 else
 982                         our_head_points_at = remote_head_points_at;
 983         }
 984         else {
 985                 if (option_branch)
 986                         die(_("Remote branch %s not found in upstream %s"),
 987                                         option_branch, option_origin);
 988
 989                 warning(_("You appear to have cloned an empty repository."));
 990                 mapped_refs = NULL;
 991                 our_head_points_at = NULL;
 992                 remote_head_points_at = NULL;
 993                 remote_head = NULL;
 994                 option_no_checkout = 1;
 995                 if (!option_bare)
 996                         install_branch_config(0, "master", option_origin,
 997                                               "refs/heads/master");
 998         }
 999
1000         write_refspec_config(src_ref_prefix, our_head_points_at,
1001                         remote_head_points_at, &branch_top);
1002
1003         if (is_local)
1004                 clone_local(path, git_dir);
1005         else if (refs && complete_refs_before_fetch)
1006                 transport_fetch_refs(transport, mapped_refs);
1007
1008         update_remote_refs(refs, mapped_refs, remote_head_points_at,
1009                            branch_top.buf, reflog_msg.buf, transport, !is_local);
1010
1011         update_head(our_head_points_at, remote_head, reflog_msg.buf);
1012
1013         transport_unlock_pack(transport);
1014         transport_disconnect(transport);
1015
1016         if (option_dissociate)
1017                 dissociate_from_references();
1018
1019         junk_mode = JUNK_LEAVE_REPO;
1020         err = checkout();
1021
1022         strbuf_release(&reflog_msg);
1023         strbuf_release(&branch_top);
1024         strbuf_release(&key);
1025         strbuf_release(&value);
1026         junk_mode = JUNK_LEAVE_ALL;
1027
1028         free(refspec);
1029         return err;
1030 }