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 "parse-options.h"
  13 #include "fetch-pack.h"
  14 #include "refs.h"
  15 #include "tree.h"
  16 #include "tree-walk.h"
  17 #include "unpack-trees.h"
  18 #include "transport.h"
  19 #include "strbuf.h"
  20 #include "dir.h"
  21 #include "sigchain.h"
  22 #include "branch.h"
  23 #include "remote.h"
  24 #include "run-command.h"
  25 #include "connected.h"
  26
  27 /*
  28  * Overall FIXMEs:
  29  *  - respect DB_ENVIRONMENT for .git/objects.
  30  *
  31  * Implementation notes:
  32  *  - dropping use-separate-remote and no-separate-remote compatibility
  33  *
  34  */
  35 static const char * const builtin_clone_usage[] = {
  36         N_("git clone [options] [--] <repo> [<dir>]"),
  37         NULL
  38 };
  39
  40 static int option_no_checkout, option_bare, option_mirror, option_single_branch = -1;
  41 static int option_local = -1, option_no_hardlinks, option_shared, option_recursive;
  42 static char *option_template, *option_depth;
  43 static char *option_origin = NULL;
  44 static char *option_branch = NULL;
  45 static const char *real_git_dir;
  46 static char *option_upload_pack = "git-upload-pack";
  47 static int option_verbosity;
  48 static int option_progress = -1;
  49 static struct string_list option_config;
  50 static struct string_list option_reference;
  51
  52 static int opt_parse_reference(const struct option *opt, const char *arg, int unset)
  53 {
  54         struct string_list *option_reference = opt->value;
  55         if (!arg)
  56                 return -1;
  57         string_list_append(option_reference, arg);
  58         return 0;
  59 }
  60
  61 static struct option builtin_clone_options[] = {
  62         OPT__VERBOSITY(&option_verbosity),
  63         OPT_BOOL(0, "progress", &option_progress,
  64                  N_("force progress reporting")),
  65         OPT_BOOL('n', "no-checkout", &option_no_checkout,
  66                  N_("don't create a checkout")),
  67         OPT_BOOL(0, "bare", &option_bare, N_("create a bare repository")),
  68         OPT_HIDDEN_BOOL(0, "naked", &option_bare,
  69                         N_("create a bare repository")),
  70         OPT_BOOL(0, "mirror", &option_mirror,
  71                  N_("create a mirror repository (implies bare)")),
  72         OPT_BOOL('l', "local", &option_local,
  73                 N_("to clone from a local repository")),
  74         OPT_BOOL(0, "no-hardlinks", &option_no_hardlinks,
  75                     N_("don't use local hardlinks, always copy")),
  76         OPT_BOOL('s', "shared", &option_shared,
  77                     N_("setup as shared repository")),
  78         OPT_BOOL(0, "recursive", &option_recursive,
  79                     N_("initialize submodules in the clone")),
  80         OPT_BOOL(0, "recurse-submodules", &option_recursive,
  81                     N_("initialize submodules in the clone")),
  82         OPT_STRING(0, "template", &option_template, N_("template-directory"),
  83                    N_("directory from which templates will be used")),
  84         OPT_CALLBACK(0 , "reference", &option_reference, N_("repo"),
  85                      N_("reference repository"), &opt_parse_reference),
  86         OPT_STRING('o', "origin", &option_origin, N_("name"),
  87                    N_("use <name> instead of 'origin' to track upstream")),
  88         OPT_STRING('b', "branch", &option_branch, N_("branch"),
  89                    N_("checkout <branch> instead of the remote's HEAD")),
  90         OPT_STRING('u', "upload-pack", &option_upload_pack, N_("path"),
  91                    N_("path to git-upload-pack on the remote")),
  92         OPT_STRING(0, "depth", &option_depth, N_("depth"),
  93                     N_("create a shallow clone of that depth")),
  94         OPT_BOOL(0, "single-branch", &option_single_branch,
  95                     N_("clone only one branch, HEAD or --branch")),
  96         OPT_STRING(0, "separate-git-dir", &real_git_dir, N_("gitdir"),
  97                    N_("separate git dir from working tree")),
  98         OPT_STRING_LIST('c', "config", &option_config, N_("key=value"),
  99                         N_("set config inside the new repository")),
 100         OPT_END()
 101 };
 102
 103 static const char *argv_submodule[] = {
 104         "submodule", "update", "--init", "--recursive", NULL
 105 };
 106
 107 static char *get_repo_path(const char *repo, int *is_bundle)
 108 {
 109         static char *suffix[] = { "/.git", "", ".git/.git", ".git" };
 110         static char *bundle_suffix[] = { ".bundle", "" };
 111         struct stat st;
 112         int i;
 113
 114         for (i = 0; i < ARRAY_SIZE(suffix); i++) {
 115                 const char *path;
 116                 path = mkpath("%s%s", repo, suffix[i]);
 117                 if (stat(path, &st))
 118                         continue;
 119                 if (S_ISDIR(st.st_mode) && is_git_directory(path)) {
 120                         *is_bundle = 0;
 121                         return xstrdup(absolute_path(path));
 122                 } else if (S_ISREG(st.st_mode) && st.st_size > 8) {
 123                         /* Is it a "gitfile"? */
 124                         char signature[8];
 125                         int len, fd = open(path, O_RDONLY);
 126                         if (fd < 0)
 127                                 continue;
 128                         len = read_in_full(fd, signature, 8);
 129                         close(fd);
 130                         if (len != 8 || strncmp(signature, "gitdir: ", 8))
 131                                 continue;
 132                         path = read_gitfile(path);
 133                         if (path) {
 134                                 *is_bundle = 0;
 135                                 return xstrdup(absolute_path(path));
 136                         }
 137                 }
 138         }
 139
 140         for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
 141                 const char *path;
 142                 path = mkpath("%s%s", repo, bundle_suffix[i]);
 143                 if (!stat(path, &st) && S_ISREG(st.st_mode)) {
 144                         *is_bundle = 1;
 145                         return xstrdup(absolute_path(path));
 146                 }
 147         }
 148
 149         return NULL;
 150 }
 151
 152 static char *guess_dir_name(const char *repo, int is_bundle, int is_bare)
 153 {
 154         const char *end = repo + strlen(repo), *start;
 155         char *dir;
 156
 157         /*
 158          * Strip trailing spaces, slashes and /.git
 159          */
 160         while (repo < end && (is_dir_sep(end[-1]) || isspace(end[-1])))
 161                 end--;
 162         if (end - repo > 5 && is_dir_sep(end[-5]) &&
 163             !strncmp(end - 4, ".git", 4)) {
 164                 end -= 5;
 165                 while (repo < end && is_dir_sep(end[-1]))
 166                         end--;
 167         }
 168
 169         /*
 170          * Find last component, but be prepared that repo could have
 171          * the form  "remote.example.com:foo.git", i.e. no slash
 172          * in the directory part.
 173          */
 174         start = end;
 175         while (repo < start && !is_dir_sep(start[-1]) && start[-1] != ':')
 176                 start--;
 177
 178         /*
 179          * Strip .{bundle,git}.
 180          */
 181         if (is_bundle) {
 182                 if (end - start > 7 && !strncmp(end - 7, ".bundle", 7))
 183                         end -= 7;
 184         } else {
 185                 if (end - start > 4 && !strncmp(end - 4, ".git", 4))
 186                         end -= 4;
 187         }
 188
 189         if (is_bare) {
 190                 struct strbuf result = STRBUF_INIT;
 191                 strbuf_addf(&result, "%.*s.git", (int)(end - start), start);
 192                 dir = strbuf_detach(&result, NULL);
 193         } else
 194                 dir = xstrndup(start, end - start);
 195         /*
 196          * Replace sequences of 'control' characters and whitespace
 197          * with one ascii space, remove leading and trailing spaces.
 198          */
 199         if (*dir) {
 200                 char *out = dir;
 201                 int prev_space = 1 /* strip leading whitespace */;
 202                 for (end = dir; *end; ++end) {
 203                         char ch = *end;
 204                         if ((unsigned char)ch < '\x20')
 205                                 ch = '\x20';
 206                         if (isspace(ch)) {
 207                                 if (prev_space)
 208                                         continue;
 209                                 prev_space = 1;
 210                         } else
 211                                 prev_space = 0;
 212                         *out++ = ch;
 213                 }
 214                 *out = '\0';
 215                 if (out > dir && prev_space)
 216                         out[-1] = '\0';
 217         }
 218         return dir;
 219 }
 220
 221 static void strip_trailing_slashes(char *dir)
 222 {
 223         char *end = dir + strlen(dir);
 224
 225         while (dir < end - 1 && is_dir_sep(end[-1]))
 226                 end--;
 227         *end = '\0';
 228 }
 229
 230 static int add_one_reference(struct string_list_item *item, void *cb_data)
 231 {
 232         char *ref_git;
 233         const char *repo;
 234         struct strbuf alternate = STRBUF_INIT;
 235
 236         /* Beware: read_gitfile(), real_path() and mkpath() return static buffer */
 237         ref_git = xstrdup(real_path(item->string));
 238
 239         repo = read_gitfile(ref_git);
 240         if (!repo)
 241                 repo = read_gitfile(mkpath("%s/.git", ref_git));
 242         if (repo) {
 243                 free(ref_git);
 244                 ref_git = xstrdup(repo);
 245         }
 246
 247         if (!repo && is_directory(mkpath("%s/.git/objects", ref_git))) {
 248                 char *ref_git_git = mkpathdup("%s/.git", ref_git);
 249                 free(ref_git);
 250                 ref_git = ref_git_git;
 251         } else if (!is_directory(mkpath("%s/objects", ref_git)))
 252                 die(_("reference repository '%s' is not a local repository."),
 253                     item->string);
 254
 255         if (!access(mkpath("%s/shallow", ref_git), F_OK))
 256                 die(_("reference repository '%s' is shallow"), item->string);
 257
 258         if (!access(mkpath("%s/info/grafts", ref_git), F_OK))
 259                 die(_("reference repository '%s' is grafted"), item->string);
 260
 261         strbuf_addf(&alternate, "%s/objects", ref_git);
 262         add_to_alternates_file(alternate.buf);
 263         strbuf_release(&alternate);
 264         free(ref_git);
 265         return 0;
 266 }
 267
 268 static void setup_reference(void)
 269 {
 270         for_each_string_list(&option_reference, add_one_reference, NULL);
 271 }
 272
 273 static void copy_alternates(struct strbuf *src, struct strbuf *dst,
 274                             const char *src_repo)
 275 {
 276         /*
 277          * Read from the source objects/info/alternates file
 278          * and copy the entries to corresponding file in the
 279          * destination repository with add_to_alternates_file().
 280          * Both src and dst have "$path/objects/info/alternates".
 281          *
 282          * Instead of copying bit-for-bit from the original,
 283          * we need to append to existing one so that the already
 284          * created entry via "clone -s" is not lost, and also
 285          * to turn entries with paths relative to the original
 286          * absolute, so that they can be used in the new repository.
 287          */
 288         FILE *in = fopen(src->buf, "r");
 289         struct strbuf line = STRBUF_INIT;
 290
 291         while (strbuf_getline(&line, in, '\n') != EOF) {
 292                 char *abs_path, abs_buf[PATH_MAX];
 293                 if (!line.len || line.buf[0] == '#')
 294                         continue;
 295                 if (is_absolute_path(line.buf)) {
 296                         add_to_alternates_file(line.buf);
 297                         continue;
 298                 }
 299                 abs_path = mkpath("%s/objects/%s", src_repo, line.buf);
 300                 normalize_path_copy(abs_buf, abs_path);
 301                 add_to_alternates_file(abs_buf);
 302         }
 303         strbuf_release(&line);
 304         fclose(in);
 305 }
 306
 307 static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
 308                                    const char *src_repo, int src_baselen)
 309 {
 310         struct dirent *de;
 311         struct stat buf;
 312         int src_len, dest_len;
 313         DIR *dir;
 314
 315         dir = opendir(src->buf);
 316         if (!dir)
 317                 die_errno(_("failed to open '%s'"), src->buf);
 318
 319         if (mkdir(dest->buf, 0777)) {
 320                 if (errno != EEXIST)
 321                         die_errno(_("failed to create directory '%s'"), dest->buf);
 322                 else if (stat(dest->buf, &buf))
 323                         die_errno(_("failed to stat '%s'"), dest->buf);
 324                 else if (!S_ISDIR(buf.st_mode))
 325                         die(_("%s exists and is not a directory"), dest->buf);
 326         }
 327
 328         strbuf_addch(src, '/');
 329         src_len = src->len;
 330         strbuf_addch(dest, '/');
 331         dest_len = dest->len;
 332
 333         while ((de = readdir(dir)) != NULL) {
 334                 strbuf_setlen(src, src_len);
 335                 strbuf_addstr(src, de->d_name);
 336                 strbuf_setlen(dest, dest_len);
 337                 strbuf_addstr(dest, de->d_name);
 338                 if (stat(src->buf, &buf)) {
 339                         warning (_("failed to stat %s\n"), src->buf);
 340                         continue;
 341                 }
 342                 if (S_ISDIR(buf.st_mode)) {
 343                         if (de->d_name[0] != '.')
 344                                 copy_or_link_directory(src, dest,
 345                                                        src_repo, src_baselen);
 346                         continue;
 347                 }
 348
 349                 /* Files that cannot be copied bit-for-bit... */
 350                 if (!strcmp(src->buf + src_baselen, "/info/alternates")) {
 351                         copy_alternates(src, dest, src_repo);
 352                         continue;
 353                 }
 354
 355                 if (unlink(dest->buf) && errno != ENOENT)
 356                         die_errno(_("failed to unlink '%s'"), dest->buf);
 357                 if (!option_no_hardlinks) {
 358                         if (!link(src->buf, dest->buf))
 359                                 continue;
 360                         if (option_local > 0)
 361                                 die_errno(_("failed to create link '%s'"), dest->buf);
 362                         option_no_hardlinks = 1;
 363                 }
 364                 if (copy_file_with_time(dest->buf, src->buf, 0666))
 365                         die_errno(_("failed to copy file to '%s'"), dest->buf);
 366         }
 367         closedir(dir);
 368 }
 369
 370 static void clone_local(const char *src_repo, const char *dest_repo)
 371 {
 372         if (option_shared) {
 373                 struct strbuf alt = STRBUF_INIT;
 374                 strbuf_addf(&alt, "%s/objects", src_repo);
 375                 add_to_alternates_file(alt.buf);
 376                 strbuf_release(&alt);
 377         } else {
 378                 struct strbuf src = STRBUF_INIT;
 379                 struct strbuf dest = STRBUF_INIT;
 380                 strbuf_addf(&src, "%s/objects", src_repo);
 381                 strbuf_addf(&dest, "%s/objects", dest_repo);
 382                 copy_or_link_directory(&src, &dest, src_repo, src.len);
 383                 strbuf_release(&src);
 384                 strbuf_release(&dest);
 385         }
 386
 387         if (0 <= option_verbosity)
 388                 fprintf(stderr, _("done.\n"));
 389 }
 390
 391 static const char *junk_work_tree;
 392 static const char *junk_git_dir;
 393 static pid_t junk_pid;
 394 static enum {
 395         JUNK_LEAVE_NONE,
 396         JUNK_LEAVE_REPO,
 397         JUNK_LEAVE_ALL
 398 } junk_mode = JUNK_LEAVE_NONE;
 399
 400 static const char junk_leave_repo_msg[] =
 401 N_("Clone succeeded, but checkout failed.\n"
 402    "You can inspect what was checked out with 'git status'\n"
 403    "and retry the checkout with 'git checkout -f HEAD'\n");
 404
 405 static void remove_junk(void)
 406 {
 407         struct strbuf sb = STRBUF_INIT;
 408
 409         switch (junk_mode) {
 410         case JUNK_LEAVE_REPO:
 411                 warning("%s", _(junk_leave_repo_msg));
 412                 /* fall-through */
 413         case JUNK_LEAVE_ALL:
 414                 return;
 415         default:
 416                 /* proceed to removal */
 417                 break;
 418         }
 419
 420         if (getpid() != junk_pid)
 421                 return;
 422         if (junk_git_dir) {
 423                 strbuf_addstr(&sb, junk_git_dir);
 424                 remove_dir_recursively(&sb, 0);
 425                 strbuf_reset(&sb);
 426         }
 427         if (junk_work_tree) {
 428                 strbuf_addstr(&sb, junk_work_tree);
 429                 remove_dir_recursively(&sb, 0);
 430                 strbuf_reset(&sb);
 431         }
 432 }
 433
 434 static void remove_junk_on_signal(int signo)
 435 {
 436         remove_junk();
 437         sigchain_pop(signo);
 438         raise(signo);
 439 }
 440
 441 static struct ref *find_remote_branch(const struct ref *refs, const char *branch)
 442 {
 443         struct ref *ref;
 444         struct strbuf head = STRBUF_INIT;
 445         strbuf_addstr(&head, "refs/heads/");
 446         strbuf_addstr(&head, branch);
 447         ref = find_ref_by_name(refs, head.buf);
 448         strbuf_release(&head);
 449
 450         if (ref)
 451                 return ref;
 452
 453         strbuf_addstr(&head, "refs/tags/");
 454         strbuf_addstr(&head, branch);
 455         ref = find_ref_by_name(refs, head.buf);
 456         strbuf_release(&head);
 457
 458         return ref;
 459 }
 460
 461 static struct ref *wanted_peer_refs(const struct ref *refs,
 462                 struct refspec *refspec)
 463 {
 464         struct ref *head = copy_ref(find_ref_by_name(refs, "HEAD"));
 465         struct ref *local_refs = head;
 466         struct ref **tail = head ? &head->next : &local_refs;
 467
 468         if (option_single_branch) {
 469                 struct ref *remote_head = NULL;
 470
 471                 if (!option_branch)
 472                         remote_head = guess_remote_head(head, refs, 0);
 473                 else {
 474                         local_refs = NULL;
 475                         tail = &local_refs;
 476                         remote_head = copy_ref(find_remote_branch(refs, option_branch));
 477                 }
 478
 479                 if (!remote_head && option_branch)
 480                         warning(_("Could not find remote branch %s to clone."),
 481                                 option_branch);
 482                 else {
 483                         get_fetch_map(remote_head, refspec, &tail, 0);
 484
 485                         /* if --branch=tag, pull the requested tag explicitly */
 486                         get_fetch_map(remote_head, tag_refspec, &tail, 0);
 487                 }
 488         } else
 489                 get_fetch_map(refs, refspec, &tail, 0);
 490
 491         if (!option_mirror && !option_single_branch)
 492                 get_fetch_map(refs, tag_refspec, &tail, 0);
 493
 494         return local_refs;
 495 }
 496
 497 static void write_remote_refs(const struct ref *local_refs)
 498 {
 499         const struct ref *r;
 500
 501         lock_packed_refs(LOCK_DIE_ON_ERROR);
 502
 503         for (r = local_refs; r; r = r->next) {
 504                 if (!r->peer_ref)
 505                         continue;
 506                 add_packed_ref(r->peer_ref->name, r->old_sha1);
 507         }
 508
 509         if (commit_packed_refs())
 510                 die_errno("unable to overwrite old ref-pack file");
 511 }
 512
 513 static void write_followtags(const struct ref *refs, const char *msg)
 514 {
 515         const struct ref *ref;
 516         for (ref = refs; ref; ref = ref->next) {
 517                 if (!starts_with(ref->name, "refs/tags/"))
 518                         continue;
 519                 if (ends_with(ref->name, "^{}"))
 520                         continue;
 521                 if (!has_sha1_file(ref->old_sha1))
 522                         continue;
 523                 update_ref(msg, ref->name, ref->old_sha1,
 524                            NULL, 0, UPDATE_REFS_DIE_ON_ERR);
 525         }
 526 }
 527
 528 static int iterate_ref_map(void *cb_data, unsigned char sha1[20])
 529 {
 530         struct ref **rm = cb_data;
 531         struct ref *ref = *rm;
 532
 533         /*
 534          * Skip anything missing a peer_ref, which we are not
 535          * actually going to write a ref for.
 536          */
 537         while (ref && !ref->peer_ref)
 538                 ref = ref->next;
 539         /* Returning -1 notes "end of list" to the caller. */
 540         if (!ref)
 541                 return -1;
 542
 543         hashcpy(sha1, ref->old_sha1);
 544         *rm = ref->next;
 545         return 0;
 546 }
 547
 548 static void update_remote_refs(const struct ref *refs,
 549                                const struct ref *mapped_refs,
 550                                const struct ref *remote_head_points_at,
 551                                const char *branch_top,
 552                                const char *msg,
 553                                struct transport *transport,
 554                                int check_connectivity)
 555 {
 556         const struct ref *rm = mapped_refs;
 557
 558         if (check_connectivity) {
 559                 if (transport->progress)
 560                         fprintf(stderr, _("Checking connectivity... "));
 561                 if (check_everything_connected_with_transport(iterate_ref_map,
 562                                                               0, &rm, transport))
 563                         die(_("remote did not send all necessary objects"));
 564                 if (transport->progress)
 565                         fprintf(stderr, _("done.\n"));
 566         }
 567
 568         if (refs) {
 569                 write_remote_refs(mapped_refs);
 570                 if (option_single_branch)
 571                         write_followtags(refs, msg);
 572         }
 573
 574         if (remote_head_points_at && !option_bare) {
 575                 struct strbuf head_ref = STRBUF_INIT;
 576                 strbuf_addstr(&head_ref, branch_top);
 577                 strbuf_addstr(&head_ref, "HEAD");
 578                 create_symref(head_ref.buf,
 579                               remote_head_points_at->peer_ref->name,
 580                               msg);
 581         }
 582 }
 583
 584 static void update_head(const struct ref *our, const struct ref *remote,
 585                         const char *msg)
 586 {
 587         const char *head;
 588         if (our && skip_prefix(our->name, "refs/heads/", &head)) {
 589                 /* Local default branch link */
 590                 create_symref("HEAD", our->name, NULL);
 591                 if (!option_bare) {
 592                         update_ref(msg, "HEAD", our->old_sha1, NULL, 0,
 593                                    UPDATE_REFS_DIE_ON_ERR);
 594                         install_branch_config(0, head, option_origin, our->name);
 595                 }
 596         } else if (our) {
 597                 struct commit *c = lookup_commit_reference(our->old_sha1);
 598                 /* --branch specifies a non-branch (i.e. tags), detach HEAD */
 599                 update_ref(msg, "HEAD", c->object.sha1,
 600                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
 601         } else if (remote) {
 602                 /*
 603                  * We know remote HEAD points to a non-branch, or
 604                  * HEAD points to a branch but we don't know which one.
 605                  * Detach HEAD in all these cases.
 606                  */
 607                 update_ref(msg, "HEAD", remote->old_sha1,
 608                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
 609         }
 610 }
 611
 612 static int checkout(void)
 613 {
 614         unsigned char sha1[20];
 615         char *head;
 616         struct lock_file *lock_file;
 617         struct unpack_trees_options opts;
 618         struct tree *tree;
 619         struct tree_desc t;
 620         int err = 0, fd;
 621
 622         if (option_no_checkout)
 623                 return 0;
 624
 625         head = resolve_refdup("HEAD", sha1, 1, NULL);
 626         if (!head) {
 627                 warning(_("remote HEAD refers to nonexistent ref, "
 628                           "unable to checkout.\n"));
 629                 return 0;
 630         }
 631         if (!strcmp(head, "HEAD")) {
 632                 if (advice_detached_head)
 633                         detach_advice(sha1_to_hex(sha1));
 634         } else {
 635                 if (!starts_with(head, "refs/heads/"))
 636                         die(_("HEAD not found below refs/heads!"));
 637         }
 638         free(head);
 639
 640         /* We need to be in the new work tree for the checkout */
 641         setup_work_tree();
 642
 643         lock_file = xcalloc(1, sizeof(struct lock_file));
 644         fd = hold_locked_index(lock_file, 1);
 645
 646         memset(&opts, 0, sizeof opts);
 647         opts.update = 1;
 648         opts.merge = 1;
 649         opts.fn = oneway_merge;
 650         opts.verbose_update = (option_verbosity >= 0);
 651         opts.src_index = &the_index;
 652         opts.dst_index = &the_index;
 653
 654         tree = parse_tree_indirect(sha1);
 655         parse_tree(tree);
 656         init_tree_desc(&t, tree->buffer, tree->size);
 657         if (unpack_trees(1, &t, &opts) < 0)
 658                 die(_("unable to checkout working tree"));
 659
 660         if (write_cache(fd, active_cache, active_nr) ||
 661             commit_locked_index(lock_file))
 662                 die(_("unable to write new index file"));
 663
 664         err |= run_hook_le(NULL, "post-checkout", sha1_to_hex(null_sha1),
 665                            sha1_to_hex(sha1), "1", NULL);
 666
 667         if (!err && option_recursive)
 668                 err = run_command_v_opt(argv_submodule, RUN_GIT_CMD);
 669
 670         return err;
 671 }
 672
 673 static int write_one_config(const char *key, const char *value, void *data)
 674 {
 675         return git_config_set_multivar(key, value ? value : "true", "^$", 0);
 676 }
 677
 678 static void write_config(struct string_list *config)
 679 {
 680         int i;
 681
 682         for (i = 0; i < config->nr; i++) {
 683                 if (git_config_parse_parameter(config->items[i].string,
 684                                                write_one_config, NULL) < 0)
 685                         die("unable to write parameters to config file");
 686         }
 687 }
 688
 689 static void write_refspec_config(const char* src_ref_prefix,
 690                 const struct ref* our_head_points_at,
 691                 const struct ref* remote_head_points_at, struct strbuf* branch_top)
 692 {
 693         struct strbuf key = STRBUF_INIT;
 694         struct strbuf value = STRBUF_INIT;
 695
 696         if (option_mirror || !option_bare) {
 697                 if (option_single_branch && !option_mirror) {
 698                         if (option_branch) {
 699                                 if (starts_with(our_head_points_at->name, "refs/tags/"))
 700                                         strbuf_addf(&value, "+%s:%s", our_head_points_at->name,
 701                                                 our_head_points_at->name);
 702                                 else
 703                                         strbuf_addf(&value, "+%s:%s%s", our_head_points_at->name,
 704                                                 branch_top->buf, option_branch);
 705                         } else if (remote_head_points_at) {
 706                                 const char *head = remote_head_points_at->name;
 707                                 if (!skip_prefix(head, "refs/heads/", &head))
 708                                         die("BUG: remote HEAD points at non-head?");
 709
 710                                 strbuf_addf(&value, "+%s:%s%s", remote_head_points_at->name,
 711                                                 branch_top->buf, head);
 712                         }
 713                         /*
 714                          * otherwise, the next "git fetch" will
 715                          * simply fetch from HEAD without updating
 716                          * any remote-tracking branch, which is what
 717                          * we want.
 718                          */
 719                 } else {
 720                         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top->buf);
 721                 }
 722                 /* Configure the remote */
 723                 if (value.len) {
 724                         strbuf_addf(&key, "remote.%s.fetch", option_origin);
 725                         git_config_set_multivar(key.buf, value.buf, "^$", 0);
 726                         strbuf_reset(&key);
 727
 728                         if (option_mirror) {
 729                                 strbuf_addf(&key, "remote.%s.mirror", option_origin);
 730                                 git_config_set(key.buf, "true");
 731                                 strbuf_reset(&key);
 732                         }
 733                 }
 734         }
 735
 736         strbuf_release(&key);
 737         strbuf_release(&value);
 738 }
 739
 740 int cmd_clone(int argc, const char **argv, const char *prefix)
 741 {
 742         int is_bundle = 0, is_local;
 743         struct stat buf;
 744         const char *repo_name, *repo, *work_tree, *git_dir;
 745         char *path, *dir;
 746         int dest_exists;
 747         const struct ref *refs, *remote_head;
 748         const struct ref *remote_head_points_at;
 749         const struct ref *our_head_points_at;
 750         struct ref *mapped_refs;
 751         const struct ref *ref;
 752         struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
 753         struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
 754         struct transport *transport = NULL;
 755         const char *src_ref_prefix = "refs/heads/";
 756         struct remote *remote;
 757         int err = 0, complete_refs_before_fetch = 1;
 758
 759         struct refspec *refspec;
 760         const char *fetch_pattern;
 761
 762         junk_pid = getpid();
 763
 764         packet_trace_identity("clone");
 765         argc = parse_options(argc, argv, prefix, builtin_clone_options,
 766                              builtin_clone_usage, 0);
 767
 768         if (argc > 2)
 769                 usage_msg_opt(_("Too many arguments."),
 770                         builtin_clone_usage, builtin_clone_options);
 771
 772         if (argc == 0)
 773                 usage_msg_opt(_("You must specify a repository to clone."),
 774                         builtin_clone_usage, builtin_clone_options);
 775
 776         if (option_single_branch == -1)
 777                 option_single_branch = option_depth ? 1 : 0;
 778
 779         if (option_mirror)
 780                 option_bare = 1;
 781
 782         if (option_bare) {
 783                 if (option_origin)
 784                         die(_("--bare and --origin %s options are incompatible."),
 785                             option_origin);
 786                 if (real_git_dir)
 787                         die(_("--bare and --separate-git-dir are incompatible."));
 788                 option_no_checkout = 1;
 789         }
 790
 791         if (!option_origin)
 792                 option_origin = "origin";
 793
 794         repo_name = argv[0];
 795
 796         path = get_repo_path(repo_name, &is_bundle);
 797         if (path)
 798                 repo = xstrdup(absolute_path(repo_name));
 799         else if (!strchr(repo_name, ':'))
 800                 die(_("repository '%s' does not exist"), repo_name);
 801         else
 802                 repo = repo_name;
 803         is_local = option_local != 0 && path && !is_bundle;
 804         if (is_local) {
 805                 if (option_depth)
 806                         warning(_("--depth is ignored in local clones; use file:// instead."));
 807                 if (!access(mkpath("%s/shallow", path), F_OK)) {
 808                         if (option_local > 0)
 809                                 warning(_("source repository is shallow, ignoring --local"));
 810                         is_local = 0;
 811                 }
 812         }
 813         if (option_local > 0 && !is_local)
 814                 warning(_("--local is ignored"));
 815
 816         /* no need to be strict, transport_set_option() will validate it again */
 817         if (option_depth && atoi(option_depth) < 1)
 818                 die(_("depth %s is not a positive number"), option_depth);
 819
 820         if (argc == 2)
 821                 dir = xstrdup(argv[1]);
 822         else
 823                 dir = guess_dir_name(repo_name, is_bundle, option_bare);
 824         strip_trailing_slashes(dir);
 825
 826         dest_exists = !stat(dir, &buf);
 827         if (dest_exists && !is_empty_dir(dir))
 828                 die(_("destination path '%s' already exists and is not "
 829                         "an empty directory."), dir);
 830
 831         strbuf_addf(&reflog_msg, "clone: from %s", repo);
 832
 833         if (option_bare)
 834                 work_tree = NULL;
 835         else {
 836                 work_tree = getenv("GIT_WORK_TREE");
 837                 if (work_tree && !stat(work_tree, &buf))
 838                         die(_("working tree '%s' already exists."), work_tree);
 839         }
 840
 841         if (option_bare || work_tree)
 842                 git_dir = xstrdup(dir);
 843         else {
 844                 work_tree = dir;
 845                 git_dir = mkpathdup("%s/.git", dir);
 846         }
 847
 848         if (!option_bare) {
 849                 junk_work_tree = work_tree;
 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                 set_git_work_tree(work_tree);
 857         }
 858         junk_git_dir = git_dir;
 859         atexit(remove_junk);
 860         sigchain_push_common(remove_junk_on_signal);
 861
 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
 900         fetch_pattern = value.buf;
 901         refspec = parse_fetch_refspec(1, &fetch_pattern);
 902
 903         strbuf_reset(&value);
 904
 905         remote = remote_get(option_origin);
 906         transport = transport_get(remote, remote->url[0]);
 907         transport->cloning = 1;
 908
 909         if (!transport->get_refs_list || (!is_local && !transport->fetch))
 910                 die(_("Don't know how to clone %s"), transport->url);
 911
 912         transport_set_option(transport, TRANS_OPT_KEEP, "yes");
 913
 914         if (option_depth)
 915                 transport_set_option(transport, TRANS_OPT_DEPTH,
 916                                      option_depth);
 917         if (option_single_branch)
 918                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
 919
 920         transport_set_verbosity(transport, option_verbosity, option_progress);
 921
 922         if (option_upload_pack)
 923                 transport_set_option(transport, TRANS_OPT_UPLOADPACK,
 924                                      option_upload_pack);
 925
 926         if (transport->smart_options && !option_depth)
 927                 transport->smart_options->check_self_contained_and_connected = 1;
 928
 929         refs = transport_get_remote_refs(transport);
 930
 931         if (refs) {
 932                 mapped_refs = wanted_peer_refs(refs, refspec);
 933                 /*
 934                  * transport_get_remote_refs() may return refs with null sha-1
 935                  * in mapped_refs (see struct transport->get_refs_list
 936                  * comment). In that case we need fetch it early because
 937                  * remote_head code below relies on it.
 938                  *
 939                  * for normal clones, transport_get_remote_refs() should
 940                  * return reliable ref set, we can delay cloning until after
 941                  * remote HEAD check.
 942                  */
 943                 for (ref = refs; ref; ref = ref->next)
 944                         if (is_null_sha1(ref->old_sha1)) {
 945                                 complete_refs_before_fetch = 0;
 946                                 break;
 947                         }
 948
 949                 if (!is_local && !complete_refs_before_fetch)
 950                         transport_fetch_refs(transport, mapped_refs);
 951
 952                 remote_head = find_ref_by_name(refs, "HEAD");
 953                 remote_head_points_at =
 954                         guess_remote_head(remote_head, mapped_refs, 0);
 955
 956                 if (option_branch) {
 957                         our_head_points_at =
 958                                 find_remote_branch(mapped_refs, option_branch);
 959
 960                         if (!our_head_points_at)
 961                                 die(_("Remote branch %s not found in upstream %s"),
 962                                     option_branch, option_origin);
 963                 }
 964                 else
 965                         our_head_points_at = remote_head_points_at;
 966         }
 967         else {
 968                 if (option_branch)
 969                         die(_("Remote branch %s not found in upstream %s"),
 970                                         option_branch, option_origin);
 971
 972                 warning(_("You appear to have cloned an empty repository."));
 973                 mapped_refs = NULL;
 974                 our_head_points_at = NULL;
 975                 remote_head_points_at = NULL;
 976                 remote_head = NULL;
 977                 option_no_checkout = 1;
 978                 if (!option_bare)
 979                         install_branch_config(0, "master", option_origin,
 980                                               "refs/heads/master");
 981         }
 982
 983         write_refspec_config(src_ref_prefix, our_head_points_at,
 984                         remote_head_points_at, &branch_top);
 985
 986         if (is_local)
 987                 clone_local(path, git_dir);
 988         else if (refs && complete_refs_before_fetch)
 989                 transport_fetch_refs(transport, mapped_refs);
 990
 991         update_remote_refs(refs, mapped_refs, remote_head_points_at,
 992                            branch_top.buf, reflog_msg.buf, transport, !is_local);
 993
 994         update_head(our_head_points_at, remote_head, reflog_msg.buf);
 995
 996         transport_unlock_pack(transport);
 997         transport_disconnect(transport);
 998
 999         junk_mode = JUNK_LEAVE_REPO;
1000         err = checkout();
1001
1002         strbuf_release(&reflog_msg);
1003         strbuf_release(&branch_top);
1004         strbuf_release(&key);
1005         strbuf_release(&value);
1006         junk_mode = JUNK_LEAVE_ALL;
1007         return err;
1008 }