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 int opt_parse_reference(const struct option *opt, const char *arg, int unset)
  55 {
  56         struct string_list *option_reference = opt->value;
  57         if (!arg)
  58                 return -1;
  59         string_list_append(option_reference, arg);
  60         return 0;
  61 }
  62
  63 static struct option builtin_clone_options[] = {
  64         OPT__VERBOSITY(&option_verbosity),
  65         OPT_BOOL(0, "progress", &option_progress,
  66                  N_("force progress reporting")),
  67         OPT_BOOL('n', "no-checkout", &option_no_checkout,
  68                  N_("don't create a checkout")),
  69         OPT_BOOL(0, "bare", &option_bare, N_("create a bare repository")),
  70         OPT_HIDDEN_BOOL(0, "naked", &option_bare,
  71                         N_("create a bare repository")),
  72         OPT_BOOL(0, "mirror", &option_mirror,
  73                  N_("create a mirror repository (implies bare)")),
  74         OPT_BOOL('l', "local", &option_local,
  75                 N_("to clone from a local repository")),
  76         OPT_BOOL(0, "no-hardlinks", &option_no_hardlinks,
  77                     N_("don't use local hardlinks, always copy")),
  78         OPT_BOOL('s', "shared", &option_shared,
  79                     N_("setup as shared repository")),
  80         OPT_BOOL(0, "recursive", &option_recursive,
  81                     N_("initialize submodules in the clone")),
  82         OPT_BOOL(0, "recurse-submodules", &option_recursive,
  83                     N_("initialize submodules in the clone")),
  84         OPT_STRING(0, "template", &option_template, N_("template-directory"),
  85                    N_("directory from which templates will be used")),
  86         OPT_CALLBACK(0 , "reference", &option_reference, N_("repo"),
  87                      N_("reference repository"), &opt_parse_reference),
  88         OPT_STRING('o', "origin", &option_origin, N_("name"),
  89                    N_("use <name> instead of 'origin' to track upstream")),
  90         OPT_STRING('b', "branch", &option_branch, N_("branch"),
  91                    N_("checkout <branch> instead of the remote's HEAD")),
  92         OPT_STRING('u', "upload-pack", &option_upload_pack, N_("path"),
  93                    N_("path to git-upload-pack on the remote")),
  94         OPT_STRING(0, "depth", &option_depth, N_("depth"),
  95                     N_("create a shallow clone of that depth")),
  96         OPT_BOOL(0, "single-branch", &option_single_branch,
  97                     N_("clone only one branch, HEAD or --branch")),
  98         OPT_BOOL(0, "dissociate", &option_dissociate,
  99                  N_("use --reference only while cloning")),
 100         OPT_STRING(0, "separate-git-dir", &real_git_dir, N_("gitdir"),
 101                    N_("separate git dir from working tree")),
 102         OPT_STRING_LIST('c', "config", &option_config, N_("key=value"),
 103                         N_("set config inside the new repository")),
 104         OPT_END()
 105 };
 106
 107 static const char *argv_submodule[] = {
 108         "submodule", "update", "--init", "--recursive", NULL
 109 };
 110
 111 static char *get_repo_path(const char *repo, int *is_bundle)
 112 {
 113         static char *suffix[] = { "/.git", "", ".git/.git", ".git" };
 114         static char *bundle_suffix[] = { ".bundle", "" };
 115         struct stat st;
 116         int i;
 117
 118         for (i = 0; i < ARRAY_SIZE(suffix); i++) {
 119                 const char *path;
 120                 path = mkpath("%s%s", repo, suffix[i]);
 121                 if (stat(path, &st))
 122                         continue;
 123                 if (S_ISDIR(st.st_mode) && is_git_directory(path)) {
 124                         *is_bundle = 0;
 125                         return xstrdup(absolute_path(path));
 126                 } else if (S_ISREG(st.st_mode) && st.st_size > 8) {
 127                         /* Is it a "gitfile"? */
 128                         char signature[8];
 129                         int len, fd = open(path, O_RDONLY);
 130                         if (fd < 0)
 131                                 continue;
 132                         len = read_in_full(fd, signature, 8);
 133                         close(fd);
 134                         if (len != 8 || strncmp(signature, "gitdir: ", 8))
 135                                 continue;
 136                         path = read_gitfile(path);
 137                         if (path) {
 138                                 *is_bundle = 0;
 139                                 return xstrdup(absolute_path(path));
 140                         }
 141                 }
 142         }
 143
 144         for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
 145                 const char *path;
 146                 path = mkpath("%s%s", repo, bundle_suffix[i]);
 147                 if (!stat(path, &st) && S_ISREG(st.st_mode)) {
 148                         *is_bundle = 1;
 149                         return xstrdup(absolute_path(path));
 150                 }
 151         }
 152
 153         return NULL;
 154 }
 155
 156 static char *guess_dir_name(const char *repo, int is_bundle, int is_bare)
 157 {
 158         const char *end = repo + strlen(repo), *start;
 159         char *dir;
 160
 161         /*
 162          * Strip trailing spaces, slashes and /.git
 163          */
 164         while (repo < end && (is_dir_sep(end[-1]) || isspace(end[-1])))
 165                 end--;
 166         if (end - repo > 5 && is_dir_sep(end[-5]) &&
 167             !strncmp(end - 4, ".git", 4)) {
 168                 end -= 5;
 169                 while (repo < end && is_dir_sep(end[-1]))
 170                         end--;
 171         }
 172
 173         /*
 174          * Find last component, but be prepared that repo could have
 175          * the form  "remote.example.com:foo.git", i.e. no slash
 176          * in the directory part.
 177          */
 178         start = end;
 179         while (repo < start && !is_dir_sep(start[-1]) && start[-1] != ':')
 180                 start--;
 181
 182         /*
 183          * Strip .{bundle,git}.
 184          */
 185         if (is_bundle) {
 186                 if (end - start > 7 && !strncmp(end - 7, ".bundle", 7))
 187                         end -= 7;
 188         } else {
 189                 if (end - start > 4 && !strncmp(end - 4, ".git", 4))
 190                         end -= 4;
 191         }
 192
 193         if (is_bare) {
 194                 struct strbuf result = STRBUF_INIT;
 195                 strbuf_addf(&result, "%.*s.git", (int)(end - start), start);
 196                 dir = strbuf_detach(&result, NULL);
 197         } else
 198                 dir = xstrndup(start, end - start);
 199         /*
 200          * Replace sequences of 'control' characters and whitespace
 201          * with one ascii space, remove leading and trailing spaces.
 202          */
 203         if (*dir) {
 204                 char *out = dir;
 205                 int prev_space = 1 /* strip leading whitespace */;
 206                 for (end = dir; *end; ++end) {
 207                         char ch = *end;
 208                         if ((unsigned char)ch < '\x20')
 209                                 ch = '\x20';
 210                         if (isspace(ch)) {
 211                                 if (prev_space)
 212                                         continue;
 213                                 prev_space = 1;
 214                         } else
 215                                 prev_space = 0;
 216                         *out++ = ch;
 217                 }
 218                 *out = '\0';
 219                 if (out > dir && prev_space)
 220                         out[-1] = '\0';
 221         }
 222         return dir;
 223 }
 224
 225 static void strip_trailing_slashes(char *dir)
 226 {
 227         char *end = dir + strlen(dir);
 228
 229         while (dir < end - 1 && is_dir_sep(end[-1]))
 230                 end--;
 231         *end = '\0';
 232 }
 233
 234 static int add_one_reference(struct string_list_item *item, void *cb_data)
 235 {
 236         char *ref_git;
 237         const char *repo;
 238         struct strbuf alternate = STRBUF_INIT;
 239
 240         /* Beware: read_gitfile(), real_path() and mkpath() return static buffer */
 241         ref_git = xstrdup(real_path(item->string));
 242
 243         repo = read_gitfile(ref_git);
 244         if (!repo)
 245                 repo = read_gitfile(mkpath("%s/.git", ref_git));
 246         if (repo) {
 247                 free(ref_git);
 248                 ref_git = xstrdup(repo);
 249         }
 250
 251         if (!repo && is_directory(mkpath("%s/.git/objects", ref_git))) {
 252                 char *ref_git_git = mkpathdup("%s/.git", ref_git);
 253                 free(ref_git);
 254                 ref_git = ref_git_git;
 255         } else if (!is_directory(mkpath("%s/objects", ref_git)))
 256                 die(_("reference repository '%s' is not a local repository."),
 257                     item->string);
 258
 259         if (!access(mkpath("%s/shallow", ref_git), F_OK))
 260                 die(_("reference repository '%s' is shallow"), item->string);
 261
 262         if (!access(mkpath("%s/info/grafts", ref_git), F_OK))
 263                 die(_("reference repository '%s' is grafted"), item->string);
 264
 265         strbuf_addf(&alternate, "%s/objects", ref_git);
 266         add_to_alternates_file(alternate.buf);
 267         strbuf_release(&alternate);
 268         free(ref_git);
 269         return 0;
 270 }
 271
 272 static void setup_reference(void)
 273 {
 274         for_each_string_list(&option_reference, add_one_reference, NULL);
 275 }
 276
 277 static void copy_alternates(struct strbuf *src, struct strbuf *dst,
 278                             const char *src_repo)
 279 {
 280         /*
 281          * Read from the source objects/info/alternates file
 282          * and copy the entries to corresponding file in the
 283          * destination repository with add_to_alternates_file().
 284          * Both src and dst have "$path/objects/info/alternates".
 285          *
 286          * Instead of copying bit-for-bit from the original,
 287          * we need to append to existing one so that the already
 288          * created entry via "clone -s" is not lost, and also
 289          * to turn entries with paths relative to the original
 290          * absolute, so that they can be used in the new repository.
 291          */
 292         FILE *in = fopen(src->buf, "r");
 293         struct strbuf line = STRBUF_INIT;
 294
 295         while (strbuf_getline(&line, in, '\n') != EOF) {
 296                 char *abs_path;
 297                 if (!line.len || line.buf[0] == '#')
 298                         continue;
 299                 if (is_absolute_path(line.buf)) {
 300                         add_to_alternates_file(line.buf);
 301                         continue;
 302                 }
 303                 abs_path = mkpathdup("%s/objects/%s", src_repo, line.buf);
 304                 normalize_path_copy(abs_path, abs_path);
 305                 add_to_alternates_file(abs_path);
 306                 free(abs_path);
 307         }
 308         strbuf_release(&line);
 309         fclose(in);
 310 }
 311
 312 static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
 313                                    const char *src_repo, int src_baselen)
 314 {
 315         struct dirent *de;
 316         struct stat buf;
 317         int src_len, dest_len;
 318         DIR *dir;
 319
 320         dir = opendir(src->buf);
 321         if (!dir)
 322                 die_errno(_("failed to open '%s'"), src->buf);
 323
 324         if (mkdir(dest->buf, 0777)) {
 325                 if (errno != EEXIST)
 326                         die_errno(_("failed to create directory '%s'"), dest->buf);
 327                 else if (stat(dest->buf, &buf))
 328                         die_errno(_("failed to stat '%s'"), dest->buf);
 329                 else if (!S_ISDIR(buf.st_mode))
 330                         die(_("%s exists and is not a directory"), dest->buf);
 331         }
 332
 333         strbuf_addch(src, '/');
 334         src_len = src->len;
 335         strbuf_addch(dest, '/');
 336         dest_len = dest->len;
 337
 338         while ((de = readdir(dir)) != NULL) {
 339                 strbuf_setlen(src, src_len);
 340                 strbuf_addstr(src, de->d_name);
 341                 strbuf_setlen(dest, dest_len);
 342                 strbuf_addstr(dest, de->d_name);
 343                 if (stat(src->buf, &buf)) {
 344                         warning (_("failed to stat %s\n"), src->buf);
 345                         continue;
 346                 }
 347                 if (S_ISDIR(buf.st_mode)) {
 348                         if (de->d_name[0] != '.')
 349                                 copy_or_link_directory(src, dest,
 350                                                        src_repo, src_baselen);
 351                         continue;
 352                 }
 353
 354                 /* Files that cannot be copied bit-for-bit... */
 355                 if (!strcmp(src->buf + src_baselen, "/info/alternates")) {
 356                         copy_alternates(src, dest, src_repo);
 357                         continue;
 358                 }
 359
 360                 if (unlink(dest->buf) && errno != ENOENT)
 361                         die_errno(_("failed to unlink '%s'"), dest->buf);
 362                 if (!option_no_hardlinks) {
 363                         if (!link(src->buf, dest->buf))
 364                                 continue;
 365                         if (option_local > 0)
 366                                 die_errno(_("failed to create link '%s'"), dest->buf);
 367                         option_no_hardlinks = 1;
 368                 }
 369                 if (copy_file_with_time(dest->buf, src->buf, 0666))
 370                         die_errno(_("failed to copy file to '%s'"), dest->buf);
 371         }
 372         closedir(dir);
 373 }
 374
 375 static void clone_local(const char *src_repo, const char *dest_repo)
 376 {
 377         if (option_shared) {
 378                 struct strbuf alt = STRBUF_INIT;
 379                 strbuf_addf(&alt, "%s/objects", src_repo);
 380                 add_to_alternates_file(alt.buf);
 381                 strbuf_release(&alt);
 382         } else {
 383                 struct strbuf src = STRBUF_INIT;
 384                 struct strbuf dest = STRBUF_INIT;
 385                 strbuf_addf(&src, "%s/objects", src_repo);
 386                 strbuf_addf(&dest, "%s/objects", dest_repo);
 387                 copy_or_link_directory(&src, &dest, src_repo, src.len);
 388                 strbuf_release(&src);
 389                 strbuf_release(&dest);
 390         }
 391
 392         if (0 <= option_verbosity)
 393                 fprintf(stderr, _("done.\n"));
 394 }
 395
 396 static const char *junk_work_tree;
 397 static const char *junk_git_dir;
 398 static enum {
 399         JUNK_LEAVE_NONE,
 400         JUNK_LEAVE_REPO,
 401         JUNK_LEAVE_ALL
 402 } junk_mode = JUNK_LEAVE_NONE;
 403
 404 static const char junk_leave_repo_msg[] =
 405 N_("Clone succeeded, but checkout failed.\n"
 406    "You can inspect what was checked out with 'git status'\n"
 407    "and retry the checkout with 'git checkout -f HEAD'\n");
 408
 409 static void remove_junk(void)
 410 {
 411         struct strbuf sb = STRBUF_INIT;
 412
 413         switch (junk_mode) {
 414         case JUNK_LEAVE_REPO:
 415                 warning("%s", _(junk_leave_repo_msg));
 416                 /* fall-through */
 417         case JUNK_LEAVE_ALL:
 418                 return;
 419         default:
 420                 /* proceed to removal */
 421                 break;
 422         }
 423
 424         if (junk_git_dir) {
 425                 strbuf_addstr(&sb, junk_git_dir);
 426                 remove_dir_recursively(&sb, 0);
 427                 strbuf_reset(&sb);
 428         }
 429         if (junk_work_tree) {
 430                 strbuf_addstr(&sb, junk_work_tree);
 431                 remove_dir_recursively(&sb, 0);
 432                 strbuf_reset(&sb);
 433         }
 434 }
 435
 436 static void remove_junk_on_signal(int signo)
 437 {
 438         remove_junk();
 439         sigchain_pop(signo);
 440         raise(signo);
 441 }
 442
 443 static struct ref *find_remote_branch(const struct ref *refs, const char *branch)
 444 {
 445         struct ref *ref;
 446         struct strbuf head = STRBUF_INIT;
 447         strbuf_addstr(&head, "refs/heads/");
 448         strbuf_addstr(&head, branch);
 449         ref = find_ref_by_name(refs, head.buf);
 450         strbuf_release(&head);
 451
 452         if (ref)
 453                 return ref;
 454
 455         strbuf_addstr(&head, "refs/tags/");
 456         strbuf_addstr(&head, branch);
 457         ref = find_ref_by_name(refs, head.buf);
 458         strbuf_release(&head);
 459
 460         return ref;
 461 }
 462
 463 static struct ref *wanted_peer_refs(const struct ref *refs,
 464                 struct refspec *refspec)
 465 {
 466         struct ref *head = copy_ref(find_ref_by_name(refs, "HEAD"));
 467         struct ref *local_refs = head;
 468         struct ref **tail = head ? &head->next : &local_refs;
 469
 470         if (option_single_branch) {
 471                 struct ref *remote_head = NULL;
 472
 473                 if (!option_branch)
 474                         remote_head = guess_remote_head(head, refs, 0);
 475                 else {
 476                         local_refs = NULL;
 477                         tail = &local_refs;
 478                         remote_head = copy_ref(find_remote_branch(refs, option_branch));
 479                 }
 480
 481                 if (!remote_head && option_branch)
 482                         warning(_("Could not find remote branch %s to clone."),
 483                                 option_branch);
 484                 else {
 485                         get_fetch_map(remote_head, refspec, &tail, 0);
 486
 487                         /* if --branch=tag, pull the requested tag explicitly */
 488                         get_fetch_map(remote_head, tag_refspec, &tail, 0);
 489                 }
 490         } else
 491                 get_fetch_map(refs, refspec, &tail, 0);
 492
 493         if (!option_mirror && !option_single_branch)
 494                 get_fetch_map(refs, tag_refspec, &tail, 0);
 495
 496         return local_refs;
 497 }
 498
 499 static void write_remote_refs(const struct ref *local_refs)
 500 {
 501         const struct ref *r;
 502
 503         lock_packed_refs(LOCK_DIE_ON_ERROR);
 504
 505         for (r = local_refs; r; r = r->next) {
 506                 if (!r->peer_ref)
 507                         continue;
 508                 add_packed_ref(r->peer_ref->name, r->old_sha1);
 509         }
 510
 511         if (commit_packed_refs())
 512                 die_errno("unable to overwrite old ref-pack file");
 513 }
 514
 515 static void write_followtags(const struct ref *refs, const char *msg)
 516 {
 517         const struct ref *ref;
 518         for (ref = refs; ref; ref = ref->next) {
 519                 if (!starts_with(ref->name, "refs/tags/"))
 520                         continue;
 521                 if (ends_with(ref->name, "^{}"))
 522                         continue;
 523                 if (!has_sha1_file(ref->old_sha1))
 524                         continue;
 525                 update_ref(msg, ref->name, ref->old_sha1,
 526                            NULL, 0, UPDATE_REFS_DIE_ON_ERR);
 527         }
 528 }
 529
 530 static int iterate_ref_map(void *cb_data, unsigned char sha1[20])
 531 {
 532         struct ref **rm = cb_data;
 533         struct ref *ref = *rm;
 534
 535         /*
 536          * Skip anything missing a peer_ref, which we are not
 537          * actually going to write a ref for.
 538          */
 539         while (ref && !ref->peer_ref)
 540                 ref = ref->next;
 541         /* Returning -1 notes "end of list" to the caller. */
 542         if (!ref)
 543                 return -1;
 544
 545         hashcpy(sha1, ref->old_sha1);
 546         *rm = ref->next;
 547         return 0;
 548 }
 549
 550 static void update_remote_refs(const struct ref *refs,
 551                                const struct ref *mapped_refs,
 552                                const struct ref *remote_head_points_at,
 553                                const char *branch_top,
 554                                const char *msg,
 555                                struct transport *transport,
 556                                int check_connectivity)
 557 {
 558         const struct ref *rm = mapped_refs;
 559
 560         if (check_connectivity) {
 561                 if (transport->progress)
 562                         fprintf(stderr, _("Checking connectivity... "));
 563                 if (check_everything_connected_with_transport(iterate_ref_map,
 564                                                               0, &rm, transport))
 565                         die(_("remote did not send all necessary objects"));
 566                 if (transport->progress)
 567                         fprintf(stderr, _("done.\n"));
 568         }
 569
 570         if (refs) {
 571                 write_remote_refs(mapped_refs);
 572                 if (option_single_branch)
 573                         write_followtags(refs, msg);
 574         }
 575
 576         if (remote_head_points_at && !option_bare) {
 577                 struct strbuf head_ref = STRBUF_INIT;
 578                 strbuf_addstr(&head_ref, branch_top);
 579                 strbuf_addstr(&head_ref, "HEAD");
 580                 create_symref(head_ref.buf,
 581                               remote_head_points_at->peer_ref->name,
 582                               msg);
 583         }
 584 }
 585
 586 static void update_head(const struct ref *our, const struct ref *remote,
 587                         const char *msg)
 588 {
 589         const char *head;
 590         if (our && skip_prefix(our->name, "refs/heads/", &head)) {
 591                 /* Local default branch link */
 592                 create_symref("HEAD", our->name, NULL);
 593                 if (!option_bare) {
 594                         update_ref(msg, "HEAD", our->old_sha1, NULL, 0,
 595                                    UPDATE_REFS_DIE_ON_ERR);
 596                         install_branch_config(0, head, option_origin, our->name);
 597                 }
 598         } else if (our) {
 599                 struct commit *c = lookup_commit_reference(our->old_sha1);
 600                 /* --branch specifies a non-branch (i.e. tags), detach HEAD */
 601                 update_ref(msg, "HEAD", c->object.sha1,
 602                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
 603         } else if (remote) {
 604                 /*
 605                  * We know remote HEAD points to a non-branch, or
 606                  * HEAD points to a branch but we don't know which one.
 607                  * Detach HEAD in all these cases.
 608                  */
 609                 update_ref(msg, "HEAD", remote->old_sha1,
 610                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
 611         }
 612 }
 613
 614 static int checkout(void)
 615 {
 616         unsigned char sha1[20];
 617         char *head;
 618         struct lock_file *lock_file;
 619         struct unpack_trees_options opts;
 620         struct tree *tree;
 621         struct tree_desc t;
 622         int err = 0;
 623
 624         if (option_no_checkout)
 625                 return 0;
 626
 627         head = resolve_refdup("HEAD", RESOLVE_REF_READING, sha1, NULL);
 628         if (!head) {
 629                 warning(_("remote HEAD refers to nonexistent ref, "
 630                           "unable to checkout.\n"));
 631                 return 0;
 632         }
 633         if (!strcmp(head, "HEAD")) {
 634                 if (advice_detached_head)
 635                         detach_advice(sha1_to_hex(sha1));
 636         } else {
 637                 if (!starts_with(head, "refs/heads/"))
 638                         die(_("HEAD not found below refs/heads!"));
 639         }
 640         free(head);
 641
 642         /* We need to be in the new work tree for the checkout */
 643         setup_work_tree();
 644
 645         lock_file = xcalloc(1, sizeof(struct lock_file));
 646         hold_locked_index(lock_file, 1);
 647
 648         memset(&opts, 0, sizeof opts);
 649         opts.update = 1;
 650         opts.merge = 1;
 651         opts.fn = oneway_merge;
 652         opts.verbose_update = (option_verbosity >= 0);
 653         opts.src_index = &the_index;
 654         opts.dst_index = &the_index;
 655
 656         tree = parse_tree_indirect(sha1);
 657         parse_tree(tree);
 658         init_tree_desc(&t, tree->buffer, tree->size);
 659         if (unpack_trees(1, &t, &opts) < 0)
 660                 die(_("unable to checkout working tree"));
 661
 662         if (write_locked_index(&the_index, lock_file, COMMIT_LOCK))
 663                 die(_("unable to write new index file"));
 664
 665         err |= run_hook_le(NULL, "post-checkout", sha1_to_hex(null_sha1),
 666                            sha1_to_hex(sha1), "1", NULL);
 667
 668         if (!err && option_recursive)
 669                 err = run_command_v_opt(argv_submodule, RUN_GIT_CMD);
 670
 671         return err;
 672 }
 673
 674 static int write_one_config(const char *key, const char *value, void *data)
 675 {
 676         return git_config_set_multivar(key, value ? value : "true", "^$", 0);
 677 }
 678
 679 static void write_config(struct string_list *config)
 680 {
 681         int i;
 682
 683         for (i = 0; i < config->nr; i++) {
 684                 if (git_config_parse_parameter(config->items[i].string,
 685                                                write_one_config, NULL) < 0)
 686                         die("unable to write parameters to config file");
 687         }
 688 }
 689
 690 static void write_refspec_config(const char *src_ref_prefix,
 691                 const struct ref *our_head_points_at,
 692                 const struct ref *remote_head_points_at,
 693                 struct strbuf *branch_top)
 694 {
 695         struct strbuf key = STRBUF_INIT;
 696         struct strbuf value = STRBUF_INIT;
 697
 698         if (option_mirror || !option_bare) {
 699                 if (option_single_branch && !option_mirror) {
 700                         if (option_branch) {
 701                                 if (starts_with(our_head_points_at->name, "refs/tags/"))
 702                                         strbuf_addf(&value, "+%s:%s", our_head_points_at->name,
 703                                                 our_head_points_at->name);
 704                                 else
 705                                         strbuf_addf(&value, "+%s:%s%s", our_head_points_at->name,
 706                                                 branch_top->buf, option_branch);
 707                         } else if (remote_head_points_at) {
 708                                 const char *head = remote_head_points_at->name;
 709                                 if (!skip_prefix(head, "refs/heads/", &head))
 710                                         die("BUG: remote HEAD points at non-head?");
 711
 712                                 strbuf_addf(&value, "+%s:%s%s", remote_head_points_at->name,
 713                                                 branch_top->buf, head);
 714                         }
 715                         /*
 716                          * otherwise, the next "git fetch" will
 717                          * simply fetch from HEAD without updating
 718                          * any remote-tracking branch, which is what
 719                          * we want.
 720                          */
 721                 } else {
 722                         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top->buf);
 723                 }
 724                 /* Configure the remote */
 725                 if (value.len) {
 726                         strbuf_addf(&key, "remote.%s.fetch", option_origin);
 727                         git_config_set_multivar(key.buf, value.buf, "^$", 0);
 728                         strbuf_reset(&key);
 729
 730                         if (option_mirror) {
 731                                 strbuf_addf(&key, "remote.%s.mirror", option_origin);
 732                                 git_config_set(key.buf, "true");
 733                                 strbuf_reset(&key);
 734                         }
 735                 }
 736         }
 737
 738         strbuf_release(&key);
 739         strbuf_release(&value);
 740 }
 741
 742 static void dissociate_from_references(void)
 743 {
 744         static const char* argv[] = { "repack", "-a", "-d", NULL };
 745
 746         if (run_command_v_opt(argv, RUN_GIT_CMD|RUN_COMMAND_NO_STDIN))
 747                 die(_("cannot repack to clean up"));
 748         if (unlink(git_path("objects/info/alternates")) && errno != ENOENT)
 749                 die_errno(_("cannot unlink temporary alternates file"));
 750 }
 751
 752 int cmd_clone(int argc, const char **argv, const char *prefix)
 753 {
 754         int is_bundle = 0, is_local;
 755         struct stat buf;
 756         const char *repo_name, *repo, *work_tree, *git_dir;
 757         char *path, *dir;
 758         int dest_exists;
 759         const struct ref *refs, *remote_head;
 760         const struct ref *remote_head_points_at;
 761         const struct ref *our_head_points_at;
 762         struct ref *mapped_refs;
 763         const struct ref *ref;
 764         struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
 765         struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
 766         struct transport *transport = NULL;
 767         const char *src_ref_prefix = "refs/heads/";
 768         struct remote *remote;
 769         int err = 0, complete_refs_before_fetch = 1;
 770
 771         struct refspec *refspec;
 772         const char *fetch_pattern;
 773
 774         packet_trace_identity("clone");
 775         argc = parse_options(argc, argv, prefix, builtin_clone_options,
 776                              builtin_clone_usage, 0);
 777
 778         if (argc > 2)
 779                 usage_msg_opt(_("Too many arguments."),
 780                         builtin_clone_usage, builtin_clone_options);
 781
 782         if (argc == 0)
 783                 usage_msg_opt(_("You must specify a repository to clone."),
 784                         builtin_clone_usage, builtin_clone_options);
 785
 786         if (option_single_branch == -1)
 787                 option_single_branch = option_depth ? 1 : 0;
 788
 789         if (option_mirror)
 790                 option_bare = 1;
 791
 792         if (option_bare) {
 793                 if (option_origin)
 794                         die(_("--bare and --origin %s options are incompatible."),
 795                             option_origin);
 796                 if (real_git_dir)
 797                         die(_("--bare and --separate-git-dir are incompatible."));
 798                 option_no_checkout = 1;
 799         }
 800
 801         if (!option_origin)
 802                 option_origin = "origin";
 803
 804         repo_name = argv[0];
 805
 806         path = get_repo_path(repo_name, &is_bundle);
 807         if (path)
 808                 repo = xstrdup(absolute_path(repo_name));
 809         else if (!strchr(repo_name, ':'))
 810                 die(_("repository '%s' does not exist"), repo_name);
 811         else
 812                 repo = repo_name;
 813
 814         /* no need to be strict, transport_set_option() will validate it again */
 815         if (option_depth && atoi(option_depth) < 1)
 816                 die(_("depth %s is not a positive number"), option_depth);
 817
 818         if (argc == 2)
 819                 dir = xstrdup(argv[1]);
 820         else
 821                 dir = guess_dir_name(repo_name, is_bundle, option_bare);
 822         strip_trailing_slashes(dir);
 823
 824         dest_exists = !stat(dir, &buf);
 825         if (dest_exists && !is_empty_dir(dir))
 826                 die(_("destination path '%s' already exists and is not "
 827                         "an empty directory."), dir);
 828
 829         strbuf_addf(&reflog_msg, "clone: from %s", repo);
 830
 831         if (option_bare)
 832                 work_tree = NULL;
 833         else {
 834                 work_tree = getenv("GIT_WORK_TREE");
 835                 if (work_tree && !stat(work_tree, &buf))
 836                         die(_("working tree '%s' already exists."), work_tree);
 837         }
 838
 839         if (option_bare || work_tree)
 840                 git_dir = xstrdup(dir);
 841         else {
 842                 work_tree = dir;
 843                 git_dir = mkpathdup("%s/.git", dir);
 844         }
 845
 846         atexit(remove_junk);
 847         sigchain_push_common(remove_junk_on_signal);
 848
 849         if (!option_bare) {
 850                 if (safe_create_leading_directories_const(work_tree) < 0)
 851                         die_errno(_("could not create leading directories of '%s'"),
 852                                   work_tree);
 853                 if (!dest_exists && mkdir(work_tree, 0777))
 854                         die_errno(_("could not create work tree dir '%s'"),
 855                                   work_tree);
 856                 junk_work_tree = work_tree;
 857                 set_git_work_tree(work_tree);
 858         }
 859
 860         junk_git_dir = git_dir;
 861         if (safe_create_leading_directories_const(git_dir) < 0)
 862                 die(_("could not create leading directories of '%s'"), git_dir);
 863
 864         set_git_dir_init(git_dir, real_git_dir, 0);
 865         if (real_git_dir) {
 866                 git_dir = real_git_dir;
 867                 junk_git_dir = real_git_dir;
 868         }
 869
 870         if (0 <= option_verbosity) {
 871                 if (option_bare)
 872                         fprintf(stderr, _("Cloning into bare repository '%s'...\n"), dir);
 873                 else
 874                         fprintf(stderr, _("Cloning into '%s'...\n"), dir);
 875         }
 876         init_db(option_template, INIT_DB_QUIET);
 877         write_config(&option_config);
 878
 879         git_config(git_default_config, NULL);
 880
 881         if (option_bare) {
 882                 if (option_mirror)
 883                         src_ref_prefix = "refs/";
 884                 strbuf_addstr(&branch_top, src_ref_prefix);
 885
 886                 git_config_set("core.bare", "true");
 887         } else {
 888                 strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
 889         }
 890
 891         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top.buf);
 892         strbuf_addf(&key, "remote.%s.url", option_origin);
 893         git_config_set(key.buf, repo);
 894         strbuf_reset(&key);
 895
 896         if (option_reference.nr)
 897                 setup_reference();
 898         else if (option_dissociate) {
 899                 warning(_("--dissociate given, but there is no --reference"));
 900                 option_dissociate = 0;
 901         }
 902
 903         fetch_pattern = value.buf;
 904         refspec = parse_fetch_refspec(1, &fetch_pattern);
 905
 906         strbuf_reset(&value);
 907
 908         remote = remote_get(option_origin);
 909         transport = transport_get(remote, remote->url[0]);
 910         transport_set_verbosity(transport, option_verbosity, option_progress);
 911
 912         path = get_repo_path(remote->url[0], &is_bundle);
 913         is_local = option_local != 0 && path && !is_bundle;
 914         if (is_local) {
 915                 if (option_depth)
 916                         warning(_("--depth is ignored in local clones; use file:// instead."));
 917                 if (!access(mkpath("%s/shallow", path), F_OK)) {
 918                         if (option_local > 0)
 919                                 warning(_("source repository is shallow, ignoring --local"));
 920                         is_local = 0;
 921                 }
 922         }
 923         if (option_local > 0 && !is_local)
 924                 warning(_("--local is ignored"));
 925         transport->cloning = 1;
 926
 927         if (!transport->get_refs_list || (!is_local && !transport->fetch))
 928                 die(_("Don't know how to clone %s"), transport->url);
 929
 930         transport_set_option(transport, TRANS_OPT_KEEP, "yes");
 931
 932         if (option_depth)
 933                 transport_set_option(transport, TRANS_OPT_DEPTH,
 934                                      option_depth);
 935         if (option_single_branch)
 936                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
 937
 938         if (option_upload_pack)
 939                 transport_set_option(transport, TRANS_OPT_UPLOADPACK,
 940                                      option_upload_pack);
 941
 942         if (transport->smart_options && !option_depth)
 943                 transport->smart_options->check_self_contained_and_connected = 1;
 944
 945         refs = transport_get_remote_refs(transport);
 946
 947         if (refs) {
 948                 mapped_refs = wanted_peer_refs(refs, refspec);
 949                 /*
 950                  * transport_get_remote_refs() may return refs with null sha-1
 951                  * in mapped_refs (see struct transport->get_refs_list
 952                  * comment). In that case we need fetch it early because
 953                  * remote_head code below relies on it.
 954                  *
 955                  * for normal clones, transport_get_remote_refs() should
 956                  * return reliable ref set, we can delay cloning until after
 957                  * remote HEAD check.
 958                  */
 959                 for (ref = refs; ref; ref = ref->next)
 960                         if (is_null_sha1(ref->old_sha1)) {
 961                                 complete_refs_before_fetch = 0;
 962                                 break;
 963                         }
 964
 965                 if (!is_local && !complete_refs_before_fetch)
 966                         transport_fetch_refs(transport, mapped_refs);
 967
 968                 remote_head = find_ref_by_name(refs, "HEAD");
 969                 remote_head_points_at =
 970                         guess_remote_head(remote_head, mapped_refs, 0);
 971
 972                 if (option_branch) {
 973                         our_head_points_at =
 974                                 find_remote_branch(mapped_refs, option_branch);
 975
 976                         if (!our_head_points_at)
 977                                 die(_("Remote branch %s not found in upstream %s"),
 978                                     option_branch, option_origin);
 979                 }
 980                 else
 981                         our_head_points_at = remote_head_points_at;
 982         }
 983         else {
 984                 if (option_branch)
 985                         die(_("Remote branch %s not found in upstream %s"),
 986                                         option_branch, option_origin);
 987
 988                 warning(_("You appear to have cloned an empty repository."));
 989                 mapped_refs = NULL;
 990                 our_head_points_at = NULL;
 991                 remote_head_points_at = NULL;
 992                 remote_head = NULL;
 993                 option_no_checkout = 1;
 994                 if (!option_bare)
 995                         install_branch_config(0, "master", option_origin,
 996                                               "refs/heads/master");
 997         }
 998
 999         write_refspec_config(src_ref_prefix, our_head_points_at,
1000                         remote_head_points_at, &branch_top);
1001
1002         if (is_local)
1003                 clone_local(path, git_dir);
1004         else if (refs && complete_refs_before_fetch)
1005                 transport_fetch_refs(transport, mapped_refs);
1006
1007         update_remote_refs(refs, mapped_refs, remote_head_points_at,
1008                            branch_top.buf, reflog_msg.buf, transport, !is_local);
1009
1010         update_head(our_head_points_at, remote_head, reflog_msg.buf);
1011
1012         transport_unlock_pack(transport);
1013         transport_disconnect(transport);
1014
1015         if (option_dissociate)
1016                 dissociate_from_references();
1017
1018         junk_mode = JUNK_LEAVE_REPO;
1019         err = checkout();
1020
1021         strbuf_release(&reflog_msg);
1022         strbuf_release(&branch_top);
1023         strbuf_release(&key);
1024         strbuf_release(&value);
1025         junk_mode = JUNK_LEAVE_ALL;
1026
1027         free(refspec);
1028         return err;
1029 }