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 "config.h"
  13 #include "lockfile.h"
  14 #include "parse-options.h"
  15 #include "fetch-pack.h"
  16 #include "refs.h"
  17 #include "tree.h"
  18 #include "tree-walk.h"
  19 #include "unpack-trees.h"
  20 #include "transport.h"
  21 #include "strbuf.h"
  22 #include "dir.h"
  23 #include "sigchain.h"
  24 #include "branch.h"
  25 #include "remote.h"
  26 #include "run-command.h"
  27 #include "connected.h"
  28 #include "packfile.h"
  29 #include "list-objects-filter-options.h"
  30 #include "object-store.h"
  31
  32 /*
  33  * Overall FIXMEs:
  34  *  - respect DB_ENVIRONMENT for .git/objects.
  35  *
  36  * Implementation notes:
  37  *  - dropping use-separate-remote and no-separate-remote compatibility
  38  *
  39  */
  40 static const char * const builtin_clone_usage[] = {
  41         N_("git clone [<options>] [--] <repo> [<dir>]"),
  42         NULL
  43 };
  44
  45 static int option_no_checkout, option_bare, option_mirror, option_single_branch = -1;
  46 static int option_local = -1, option_no_hardlinks, option_shared;
  47 static int option_no_tags;
  48 static int option_shallow_submodules;
  49 static int deepen;
  50 static char *option_template, *option_depth, *option_since;
  51 static char *option_origin = NULL;
  52 static char *option_branch = NULL;
  53 static struct string_list option_not = STRING_LIST_INIT_NODUP;
  54 static const char *real_git_dir;
  55 static char *option_upload_pack = "git-upload-pack";
  56 static int option_verbosity;
  57 static int option_progress = -1;
  58 static enum transport_family family;
  59 static struct string_list option_config = STRING_LIST_INIT_NODUP;
  60 static struct string_list option_required_reference = STRING_LIST_INIT_NODUP;
  61 static struct string_list option_optional_reference = STRING_LIST_INIT_NODUP;
  62 static int option_dissociate;
  63 static int max_jobs = -1;
  64 static struct string_list option_recurse_submodules = STRING_LIST_INIT_NODUP;
  65 static struct list_objects_filter_options filter_options;
  66
  67 static int recurse_submodules_cb(const struct option *opt,
  68                                  const char *arg, int unset)
  69 {
  70         if (unset)
  71                 string_list_clear((struct string_list *)opt->value, 0);
  72         else if (arg)
  73                 string_list_append((struct string_list *)opt->value, arg);
  74         else
  75                 string_list_append((struct string_list *)opt->value,
  76                                    (const char *)opt->defval);
  77
  78         return 0;
  79 }
  80
  81 static struct option builtin_clone_options[] = {
  82         OPT__VERBOSITY(&option_verbosity),
  83         OPT_BOOL(0, "progress", &option_progress,
  84                  N_("force progress reporting")),
  85         OPT_BOOL('n', "no-checkout", &option_no_checkout,
  86                  N_("don't create a checkout")),
  87         OPT_BOOL(0, "bare", &option_bare, N_("create a bare repository")),
  88         OPT_HIDDEN_BOOL(0, "naked", &option_bare,
  89                         N_("create a bare repository")),
  90         OPT_BOOL(0, "mirror", &option_mirror,
  91                  N_("create a mirror repository (implies bare)")),
  92         OPT_BOOL('l', "local", &option_local,
  93                 N_("to clone from a local repository")),
  94         OPT_BOOL(0, "no-hardlinks", &option_no_hardlinks,
  95                     N_("don't use local hardlinks, always copy")),
  96         OPT_BOOL('s', "shared", &option_shared,
  97                     N_("setup as shared repository")),
  98         { OPTION_CALLBACK, 0, "recursive", &option_recurse_submodules,
  99           N_("pathspec"), N_("initialize submodules in the clone"),
 100           PARSE_OPT_OPTARG | PARSE_OPT_HIDDEN, recurse_submodules_cb,
 101           (intptr_t)"." },
 102         { OPTION_CALLBACK, 0, "recurse-submodules", &option_recurse_submodules,
 103           N_("pathspec"), N_("initialize submodules in the clone"),
 104           PARSE_OPT_OPTARG, recurse_submodules_cb, (intptr_t)"." },
 105         OPT_INTEGER('j', "jobs", &max_jobs,
 106                     N_("number of submodules cloned in parallel")),
 107         OPT_STRING(0, "template", &option_template, N_("template-directory"),
 108                    N_("directory from which templates will be used")),
 109         OPT_STRING_LIST(0, "reference", &option_required_reference, N_("repo"),
 110                         N_("reference repository")),
 111         OPT_STRING_LIST(0, "reference-if-able", &option_optional_reference,
 112                         N_("repo"), N_("reference repository")),
 113         OPT_BOOL(0, "dissociate", &option_dissociate,
 114                  N_("use --reference only while cloning")),
 115         OPT_STRING('o', "origin", &option_origin, N_("name"),
 116                    N_("use <name> instead of 'origin' to track upstream")),
 117         OPT_STRING('b', "branch", &option_branch, N_("branch"),
 118                    N_("checkout <branch> instead of the remote's HEAD")),
 119         OPT_STRING('u', "upload-pack", &option_upload_pack, N_("path"),
 120                    N_("path to git-upload-pack on the remote")),
 121         OPT_STRING(0, "depth", &option_depth, N_("depth"),
 122                     N_("create a shallow clone of that depth")),
 123         OPT_STRING(0, "shallow-since", &option_since, N_("time"),
 124                     N_("create a shallow clone since a specific time")),
 125         OPT_STRING_LIST(0, "shallow-exclude", &option_not, N_("revision"),
 126                         N_("deepen history of shallow clone, excluding rev")),
 127         OPT_BOOL(0, "single-branch", &option_single_branch,
 128                     N_("clone only one branch, HEAD or --branch")),
 129         OPT_BOOL(0, "no-tags", &option_no_tags,
 130                  N_("don't clone any tags, and make later fetches not to follow them")),
 131         OPT_BOOL(0, "shallow-submodules", &option_shallow_submodules,
 132                     N_("any cloned submodules will be shallow")),
 133         OPT_STRING(0, "separate-git-dir", &real_git_dir, N_("gitdir"),
 134                    N_("separate git dir from working tree")),
 135         OPT_STRING_LIST('c', "config", &option_config, N_("key=value"),
 136                         N_("set config inside the new repository")),
 137         OPT_SET_INT('4', "ipv4", &family, N_("use IPv4 addresses only"),
 138                         TRANSPORT_FAMILY_IPV4),
 139         OPT_SET_INT('6', "ipv6", &family, N_("use IPv6 addresses only"),
 140                         TRANSPORT_FAMILY_IPV6),
 141         OPT_PARSE_LIST_OBJECTS_FILTER(&filter_options),
 142         OPT_END()
 143 };
 144
 145 static const char *get_repo_path_1(struct strbuf *path, int *is_bundle)
 146 {
 147         static char *suffix[] = { "/.git", "", ".git/.git", ".git" };
 148         static char *bundle_suffix[] = { ".bundle", "" };
 149         size_t baselen = path->len;
 150         struct stat st;
 151         int i;
 152
 153         for (i = 0; i < ARRAY_SIZE(suffix); i++) {
 154                 strbuf_setlen(path, baselen);
 155                 strbuf_addstr(path, suffix[i]);
 156                 if (stat(path->buf, &st))
 157                         continue;
 158                 if (S_ISDIR(st.st_mode) && is_git_directory(path->buf)) {
 159                         *is_bundle = 0;
 160                         return path->buf;
 161                 } else if (S_ISREG(st.st_mode) && st.st_size > 8) {
 162                         /* Is it a "gitfile"? */
 163                         char signature[8];
 164                         const char *dst;
 165                         int len, fd = open(path->buf, O_RDONLY);
 166                         if (fd < 0)
 167                                 continue;
 168                         len = read_in_full(fd, signature, 8);
 169                         close(fd);
 170                         if (len != 8 || strncmp(signature, "gitdir: ", 8))
 171                                 continue;
 172                         dst = read_gitfile(path->buf);
 173                         if (dst) {
 174                                 *is_bundle = 0;
 175                                 return dst;
 176                         }
 177                 }
 178         }
 179
 180         for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
 181                 strbuf_setlen(path, baselen);
 182                 strbuf_addstr(path, bundle_suffix[i]);
 183                 if (!stat(path->buf, &st) && S_ISREG(st.st_mode)) {
 184                         *is_bundle = 1;
 185                         return path->buf;
 186                 }
 187         }
 188
 189         return NULL;
 190 }
 191
 192 static char *get_repo_path(const char *repo, int *is_bundle)
 193 {
 194         struct strbuf path = STRBUF_INIT;
 195         const char *raw;
 196         char *canon;
 197
 198         strbuf_addstr(&path, repo);
 199         raw = get_repo_path_1(&path, is_bundle);
 200         canon = raw ? absolute_pathdup(raw) : NULL;
 201         strbuf_release(&path);
 202         return canon;
 203 }
 204
 205 static char *guess_dir_name(const char *repo, int is_bundle, int is_bare)
 206 {
 207         const char *end = repo + strlen(repo), *start, *ptr;
 208         size_t len;
 209         char *dir;
 210
 211         /*
 212          * Skip scheme.
 213          */
 214         start = strstr(repo, "://");
 215         if (start == NULL)
 216                 start = repo;
 217         else
 218                 start += 3;
 219
 220         /*
 221          * Skip authentication data. The stripping does happen
 222          * greedily, such that we strip up to the last '@' inside
 223          * the host part.
 224          */
 225         for (ptr = start; ptr < end && !is_dir_sep(*ptr); ptr++) {
 226                 if (*ptr == '@')
 227                         start = ptr + 1;
 228         }
 229
 230         /*
 231          * Strip trailing spaces, slashes and /.git
 232          */
 233         while (start < end && (is_dir_sep(end[-1]) || isspace(end[-1])))
 234                 end--;
 235         if (end - start > 5 && is_dir_sep(end[-5]) &&
 236             !strncmp(end - 4, ".git", 4)) {
 237                 end -= 5;
 238                 while (start < end && is_dir_sep(end[-1]))
 239                         end--;
 240         }
 241
 242         /*
 243          * Strip trailing port number if we've got only a
 244          * hostname (that is, there is no dir separator but a
 245          * colon). This check is required such that we do not
 246          * strip URI's like '/foo/bar:2222.git', which should
 247          * result in a dir '2222' being guessed due to backwards
 248          * compatibility.
 249          */
 250         if (memchr(start, '/', end - start) == NULL
 251             && memchr(start, ':', end - start) != NULL) {
 252                 ptr = end;
 253                 while (start < ptr && isdigit(ptr[-1]) && ptr[-1] != ':')
 254                         ptr--;
 255                 if (start < ptr && ptr[-1] == ':')
 256                         end = ptr - 1;
 257         }
 258
 259         /*
 260          * Find last component. To remain backwards compatible we
 261          * also regard colons as path separators, such that
 262          * cloning a repository 'foo:bar.git' would result in a
 263          * directory 'bar' being guessed.
 264          */
 265         ptr = end;
 266         while (start < ptr && !is_dir_sep(ptr[-1]) && ptr[-1] != ':')
 267                 ptr--;
 268         start = ptr;
 269
 270         /*
 271          * Strip .{bundle,git}.
 272          */
 273         len = end - start;
 274         strip_suffix_mem(start, &len, is_bundle ? ".bundle" : ".git");
 275
 276         if (!len || (len == 1 && *start == '/'))
 277                 die(_("No directory name could be guessed.\n"
 278                       "Please specify a directory on the command line"));
 279
 280         if (is_bare)
 281                 dir = xstrfmt("%.*s.git", (int)len, start);
 282         else
 283                 dir = xstrndup(start, len);
 284         /*
 285          * Replace sequences of 'control' characters and whitespace
 286          * with one ascii space, remove leading and trailing spaces.
 287          */
 288         if (*dir) {
 289                 char *out = dir;
 290                 int prev_space = 1 /* strip leading whitespace */;
 291                 for (end = dir; *end; ++end) {
 292                         char ch = *end;
 293                         if ((unsigned char)ch < '\x20')
 294                                 ch = '\x20';
 295                         if (isspace(ch)) {
 296                                 if (prev_space)
 297                                         continue;
 298                                 prev_space = 1;
 299                         } else
 300                                 prev_space = 0;
 301                         *out++ = ch;
 302                 }
 303                 *out = '\0';
 304                 if (out > dir && prev_space)
 305                         out[-1] = '\0';
 306         }
 307         return dir;
 308 }
 309
 310 static void strip_trailing_slashes(char *dir)
 311 {
 312         char *end = dir + strlen(dir);
 313
 314         while (dir < end - 1 && is_dir_sep(end[-1]))
 315                 end--;
 316         *end = '\0';
 317 }
 318
 319 static int add_one_reference(struct string_list_item *item, void *cb_data)
 320 {
 321         struct strbuf err = STRBUF_INIT;
 322         int *required = cb_data;
 323         char *ref_git = compute_alternate_path(item->string, &err);
 324
 325         if (!ref_git) {
 326                 if (*required)
 327                         die("%s", err.buf);
 328                 else
 329                         fprintf(stderr,
 330                                 _("info: Could not add alternate for '%s': %s\n"),
 331                                 item->string, err.buf);
 332         } else {
 333                 struct strbuf sb = STRBUF_INIT;
 334                 strbuf_addf(&sb, "%s/objects", ref_git);
 335                 add_to_alternates_file(sb.buf);
 336                 strbuf_release(&sb);
 337         }
 338
 339         strbuf_release(&err);
 340         free(ref_git);
 341         return 0;
 342 }
 343
 344 static void setup_reference(void)
 345 {
 346         int required = 1;
 347         for_each_string_list(&option_required_reference,
 348                              add_one_reference, &required);
 349         required = 0;
 350         for_each_string_list(&option_optional_reference,
 351                              add_one_reference, &required);
 352 }
 353
 354 static void copy_alternates(struct strbuf *src, struct strbuf *dst,
 355                             const char *src_repo)
 356 {
 357         /*
 358          * Read from the source objects/info/alternates file
 359          * and copy the entries to corresponding file in the
 360          * destination repository with add_to_alternates_file().
 361          * Both src and dst have "$path/objects/info/alternates".
 362          *
 363          * Instead of copying bit-for-bit from the original,
 364          * we need to append to existing one so that the already
 365          * created entry via "clone -s" is not lost, and also
 366          * to turn entries with paths relative to the original
 367          * absolute, so that they can be used in the new repository.
 368          */
 369         FILE *in = xfopen(src->buf, "r");
 370         struct strbuf line = STRBUF_INIT;
 371
 372         while (strbuf_getline(&line, in) != EOF) {
 373                 char *abs_path;
 374                 if (!line.len || line.buf[0] == '#')
 375                         continue;
 376                 if (is_absolute_path(line.buf)) {
 377                         add_to_alternates_file(line.buf);
 378                         continue;
 379                 }
 380                 abs_path = mkpathdup("%s/objects/%s", src_repo, line.buf);
 381                 if (!normalize_path_copy(abs_path, abs_path))
 382                         add_to_alternates_file(abs_path);
 383                 else
 384                         warning("skipping invalid relative alternate: %s/%s",
 385                                 src_repo, line.buf);
 386                 free(abs_path);
 387         }
 388         strbuf_release(&line);
 389         fclose(in);
 390 }
 391
 392 static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
 393                                    const char *src_repo, int src_baselen)
 394 {
 395         struct dirent *de;
 396         struct stat buf;
 397         int src_len, dest_len;
 398         DIR *dir;
 399
 400         dir = opendir(src->buf);
 401         if (!dir)
 402                 die_errno(_("failed to open '%s'"), src->buf);
 403
 404         if (mkdir(dest->buf, 0777)) {
 405                 if (errno != EEXIST)
 406                         die_errno(_("failed to create directory '%s'"), dest->buf);
 407                 else if (stat(dest->buf, &buf))
 408                         die_errno(_("failed to stat '%s'"), dest->buf);
 409                 else if (!S_ISDIR(buf.st_mode))
 410                         die(_("%s exists and is not a directory"), dest->buf);
 411         }
 412
 413         strbuf_addch(src, '/');
 414         src_len = src->len;
 415         strbuf_addch(dest, '/');
 416         dest_len = dest->len;
 417
 418         while ((de = readdir(dir)) != NULL) {
 419                 strbuf_setlen(src, src_len);
 420                 strbuf_addstr(src, de->d_name);
 421                 strbuf_setlen(dest, dest_len);
 422                 strbuf_addstr(dest, de->d_name);
 423                 if (stat(src->buf, &buf)) {
 424                         warning (_("failed to stat %s\n"), src->buf);
 425                         continue;
 426                 }
 427                 if (S_ISDIR(buf.st_mode)) {
 428                         if (de->d_name[0] != '.')
 429                                 copy_or_link_directory(src, dest,
 430                                                        src_repo, src_baselen);
 431                         continue;
 432                 }
 433
 434                 /* Files that cannot be copied bit-for-bit... */
 435                 if (!strcmp(src->buf + src_baselen, "/info/alternates")) {
 436                         copy_alternates(src, dest, src_repo);
 437                         continue;
 438                 }
 439
 440                 if (unlink(dest->buf) && errno != ENOENT)
 441                         die_errno(_("failed to unlink '%s'"), dest->buf);
 442                 if (!option_no_hardlinks) {
 443                         if (!link(src->buf, dest->buf))
 444                                 continue;
 445                         if (option_local > 0)
 446                                 die_errno(_("failed to create link '%s'"), dest->buf);
 447                         option_no_hardlinks = 1;
 448                 }
 449                 if (copy_file_with_time(dest->buf, src->buf, 0666))
 450                         die_errno(_("failed to copy file to '%s'"), dest->buf);
 451         }
 452         closedir(dir);
 453 }
 454
 455 static void clone_local(const char *src_repo, const char *dest_repo)
 456 {
 457         if (option_shared) {
 458                 struct strbuf alt = STRBUF_INIT;
 459                 get_common_dir(&alt, src_repo);
 460                 strbuf_addstr(&alt, "/objects");
 461                 add_to_alternates_file(alt.buf);
 462                 strbuf_release(&alt);
 463         } else {
 464                 struct strbuf src = STRBUF_INIT;
 465                 struct strbuf dest = STRBUF_INIT;
 466                 get_common_dir(&src, src_repo);
 467                 get_common_dir(&dest, dest_repo);
 468                 strbuf_addstr(&src, "/objects");
 469                 strbuf_addstr(&dest, "/objects");
 470                 copy_or_link_directory(&src, &dest, src_repo, src.len);
 471                 strbuf_release(&src);
 472                 strbuf_release(&dest);
 473         }
 474
 475         if (0 <= option_verbosity)
 476                 fprintf(stderr, _("done.\n"));
 477 }
 478
 479 static const char *junk_work_tree;
 480 static int junk_work_tree_flags;
 481 static const char *junk_git_dir;
 482 static int junk_git_dir_flags;
 483 static enum {
 484         JUNK_LEAVE_NONE,
 485         JUNK_LEAVE_REPO,
 486         JUNK_LEAVE_ALL
 487 } junk_mode = JUNK_LEAVE_NONE;
 488
 489 static const char junk_leave_repo_msg[] =
 490 N_("Clone succeeded, but checkout failed.\n"
 491    "You can inspect what was checked out with 'git status'\n"
 492    "and retry the checkout with 'git checkout -f HEAD'\n");
 493
 494 static void remove_junk(void)
 495 {
 496         struct strbuf sb = STRBUF_INIT;
 497
 498         switch (junk_mode) {
 499         case JUNK_LEAVE_REPO:
 500                 warning("%s", _(junk_leave_repo_msg));
 501                 /* fall-through */
 502         case JUNK_LEAVE_ALL:
 503                 return;
 504         default:
 505                 /* proceed to removal */
 506                 break;
 507         }
 508
 509         if (junk_git_dir) {
 510                 strbuf_addstr(&sb, junk_git_dir);
 511                 remove_dir_recursively(&sb, junk_git_dir_flags);
 512                 strbuf_reset(&sb);
 513         }
 514         if (junk_work_tree) {
 515                 strbuf_addstr(&sb, junk_work_tree);
 516                 remove_dir_recursively(&sb, junk_work_tree_flags);
 517         }
 518         strbuf_release(&sb);
 519 }
 520
 521 static void remove_junk_on_signal(int signo)
 522 {
 523         remove_junk();
 524         sigchain_pop(signo);
 525         raise(signo);
 526 }
 527
 528 static struct ref *find_remote_branch(const struct ref *refs, const char *branch)
 529 {
 530         struct ref *ref;
 531         struct strbuf head = STRBUF_INIT;
 532         strbuf_addstr(&head, "refs/heads/");
 533         strbuf_addstr(&head, branch);
 534         ref = find_ref_by_name(refs, head.buf);
 535         strbuf_release(&head);
 536
 537         if (ref)
 538                 return ref;
 539
 540         strbuf_addstr(&head, "refs/tags/");
 541         strbuf_addstr(&head, branch);
 542         ref = find_ref_by_name(refs, head.buf);
 543         strbuf_release(&head);
 544
 545         return ref;
 546 }
 547
 548 static struct ref *wanted_peer_refs(const struct ref *refs,
 549                 struct refspec *refspec)
 550 {
 551         struct ref *head = copy_ref(find_ref_by_name(refs, "HEAD"));
 552         struct ref *local_refs = head;
 553         struct ref **tail = head ? &head->next : &local_refs;
 554
 555         if (option_single_branch) {
 556                 struct ref *remote_head = NULL;
 557
 558                 if (!option_branch)
 559                         remote_head = guess_remote_head(head, refs, 0);
 560                 else {
 561                         local_refs = NULL;
 562                         tail = &local_refs;
 563                         remote_head = copy_ref(find_remote_branch(refs, option_branch));
 564                 }
 565
 566                 if (!remote_head && option_branch)
 567                         warning(_("Could not find remote branch %s to clone."),
 568                                 option_branch);
 569                 else {
 570                         get_fetch_map(remote_head, refspec, &tail, 0);
 571
 572                         /* if --branch=tag, pull the requested tag explicitly */
 573                         get_fetch_map(remote_head, tag_refspec, &tail, 0);
 574                 }
 575         } else
 576                 get_fetch_map(refs, refspec, &tail, 0);
 577
 578         if (!option_mirror && !option_single_branch && !option_no_tags)
 579                 get_fetch_map(refs, tag_refspec, &tail, 0);
 580
 581         return local_refs;
 582 }
 583
 584 static void write_remote_refs(const struct ref *local_refs)
 585 {
 586         const struct ref *r;
 587
 588         struct ref_transaction *t;
 589         struct strbuf err = STRBUF_INIT;
 590
 591         t = ref_transaction_begin(&err);
 592         if (!t)
 593                 die("%s", err.buf);
 594
 595         for (r = local_refs; r; r = r->next) {
 596                 if (!r->peer_ref)
 597                         continue;
 598                 if (ref_transaction_create(t, r->peer_ref->name, &r->old_oid,
 599                                            0, NULL, &err))
 600                         die("%s", err.buf);
 601         }
 602
 603         if (initial_ref_transaction_commit(t, &err))
 604                 die("%s", err.buf);
 605
 606         strbuf_release(&err);
 607         ref_transaction_free(t);
 608 }
 609
 610 static void write_followtags(const struct ref *refs, const char *msg)
 611 {
 612         const struct ref *ref;
 613         for (ref = refs; ref; ref = ref->next) {
 614                 if (!starts_with(ref->name, "refs/tags/"))
 615                         continue;
 616                 if (ends_with(ref->name, "^{}"))
 617                         continue;
 618                 if (!has_object_file(&ref->old_oid))
 619                         continue;
 620                 update_ref(msg, ref->name, &ref->old_oid, NULL, 0,
 621                            UPDATE_REFS_DIE_ON_ERR);
 622         }
 623 }
 624
 625 static int iterate_ref_map(void *cb_data, struct object_id *oid)
 626 {
 627         struct ref **rm = cb_data;
 628         struct ref *ref = *rm;
 629
 630         /*
 631          * Skip anything missing a peer_ref, which we are not
 632          * actually going to write a ref for.
 633          */
 634         while (ref && !ref->peer_ref)
 635                 ref = ref->next;
 636         /* Returning -1 notes "end of list" to the caller. */
 637         if (!ref)
 638                 return -1;
 639
 640         oidcpy(oid, &ref->old_oid);
 641         *rm = ref->next;
 642         return 0;
 643 }
 644
 645 static void update_remote_refs(const struct ref *refs,
 646                                const struct ref *mapped_refs,
 647                                const struct ref *remote_head_points_at,
 648                                const char *branch_top,
 649                                const char *msg,
 650                                struct transport *transport,
 651                                int check_connectivity)
 652 {
 653         const struct ref *rm = mapped_refs;
 654
 655         if (check_connectivity) {
 656                 struct check_connected_options opt = CHECK_CONNECTED_INIT;
 657
 658                 opt.transport = transport;
 659                 opt.progress = transport->progress;
 660
 661                 if (check_connected(iterate_ref_map, &rm, &opt))
 662                         die(_("remote did not send all necessary objects"));
 663         }
 664
 665         if (refs) {
 666                 write_remote_refs(mapped_refs);
 667                 if (option_single_branch && !option_no_tags)
 668                         write_followtags(refs, msg);
 669         }
 670
 671         if (remote_head_points_at && !option_bare) {
 672                 struct strbuf head_ref = STRBUF_INIT;
 673                 strbuf_addstr(&head_ref, branch_top);
 674                 strbuf_addstr(&head_ref, "HEAD");
 675                 if (create_symref(head_ref.buf,
 676                                   remote_head_points_at->peer_ref->name,
 677                                   msg) < 0)
 678                         die(_("unable to update %s"), head_ref.buf);
 679                 strbuf_release(&head_ref);
 680         }
 681 }
 682
 683 static void update_head(const struct ref *our, const struct ref *remote,
 684                         const char *msg)
 685 {
 686         const char *head;
 687         if (our && skip_prefix(our->name, "refs/heads/", &head)) {
 688                 /* Local default branch link */
 689                 if (create_symref("HEAD", our->name, NULL) < 0)
 690                         die(_("unable to update HEAD"));
 691                 if (!option_bare) {
 692                         update_ref(msg, "HEAD", &our->old_oid, NULL, 0,
 693                                    UPDATE_REFS_DIE_ON_ERR);
 694                         install_branch_config(0, head, option_origin, our->name);
 695                 }
 696         } else if (our) {
 697                 struct commit *c = lookup_commit_reference(&our->old_oid);
 698                 /* --branch specifies a non-branch (i.e. tags), detach HEAD */
 699                 update_ref(msg, "HEAD", &c->object.oid, NULL, REF_NO_DEREF,
 700                            UPDATE_REFS_DIE_ON_ERR);
 701         } else if (remote) {
 702                 /*
 703                  * We know remote HEAD points to a non-branch, or
 704                  * HEAD points to a branch but we don't know which one.
 705                  * Detach HEAD in all these cases.
 706                  */
 707                 update_ref(msg, "HEAD", &remote->old_oid, NULL, REF_NO_DEREF,
 708                            UPDATE_REFS_DIE_ON_ERR);
 709         }
 710 }
 711
 712 static int checkout(int submodule_progress)
 713 {
 714         struct object_id oid;
 715         char *head;
 716         struct lock_file lock_file = LOCK_INIT;
 717         struct unpack_trees_options opts;
 718         struct tree *tree;
 719         struct tree_desc t;
 720         int err = 0;
 721
 722         if (option_no_checkout)
 723                 return 0;
 724
 725         head = resolve_refdup("HEAD", RESOLVE_REF_READING, &oid, NULL);
 726         if (!head) {
 727                 warning(_("remote HEAD refers to nonexistent ref, "
 728                           "unable to checkout.\n"));
 729                 return 0;
 730         }
 731         if (!strcmp(head, "HEAD")) {
 732                 if (advice_detached_head)
 733                         detach_advice(oid_to_hex(&oid));
 734         } else {
 735                 if (!starts_with(head, "refs/heads/"))
 736                         die(_("HEAD not found below refs/heads!"));
 737         }
 738         free(head);
 739
 740         /* We need to be in the new work tree for the checkout */
 741         setup_work_tree();
 742
 743         hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
 744
 745         memset(&opts, 0, sizeof opts);
 746         opts.update = 1;
 747         opts.merge = 1;
 748         opts.fn = oneway_merge;
 749         opts.verbose_update = (option_verbosity >= 0);
 750         opts.src_index = &the_index;
 751         opts.dst_index = &the_index;
 752
 753         tree = parse_tree_indirect(&oid);
 754         parse_tree(tree);
 755         init_tree_desc(&t, tree->buffer, tree->size);
 756         if (unpack_trees(1, &t, &opts) < 0)
 757                 die(_("unable to checkout working tree"));
 758
 759         if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
 760                 die(_("unable to write new index file"));
 761
 762         err |= run_hook_le(NULL, "post-checkout", sha1_to_hex(null_sha1),
 763                            oid_to_hex(&oid), "1", NULL);
 764
 765         if (!err && (option_recurse_submodules.nr > 0)) {
 766                 struct argv_array args = ARGV_ARRAY_INIT;
 767                 argv_array_pushl(&args, "submodule", "update", "--init", "--recursive", NULL);
 768
 769                 if (option_shallow_submodules == 1)
 770                         argv_array_push(&args, "--depth=1");
 771
 772                 if (max_jobs != -1)
 773                         argv_array_pushf(&args, "--jobs=%d", max_jobs);
 774
 775                 if (submodule_progress)
 776                         argv_array_push(&args, "--progress");
 777
 778                 if (option_verbosity < 0)
 779                         argv_array_push(&args, "--quiet");
 780
 781                 err = run_command_v_opt(args.argv, RUN_GIT_CMD);
 782                 argv_array_clear(&args);
 783         }
 784
 785         return err;
 786 }
 787
 788 static int write_one_config(const char *key, const char *value, void *data)
 789 {
 790         return git_config_set_multivar_gently(key,
 791                                               value ? value : "true",
 792                                               CONFIG_REGEX_NONE, 0);
 793 }
 794
 795 static void write_config(struct string_list *config)
 796 {
 797         int i;
 798
 799         for (i = 0; i < config->nr; i++) {
 800                 if (git_config_parse_parameter(config->items[i].string,
 801                                                write_one_config, NULL) < 0)
 802                         die(_("unable to write parameters to config file"));
 803         }
 804 }
 805
 806 static void write_refspec_config(const char *src_ref_prefix,
 807                 const struct ref *our_head_points_at,
 808                 const struct ref *remote_head_points_at,
 809                 struct strbuf *branch_top)
 810 {
 811         struct strbuf key = STRBUF_INIT;
 812         struct strbuf value = STRBUF_INIT;
 813
 814         if (option_mirror || !option_bare) {
 815                 if (option_single_branch && !option_mirror) {
 816                         if (option_branch) {
 817                                 if (starts_with(our_head_points_at->name, "refs/tags/"))
 818                                         strbuf_addf(&value, "+%s:%s", our_head_points_at->name,
 819                                                 our_head_points_at->name);
 820                                 else
 821                                         strbuf_addf(&value, "+%s:%s%s", our_head_points_at->name,
 822                                                 branch_top->buf, option_branch);
 823                         } else if (remote_head_points_at) {
 824                                 const char *head = remote_head_points_at->name;
 825                                 if (!skip_prefix(head, "refs/heads/", &head))
 826                                         die("BUG: remote HEAD points at non-head?");
 827
 828                                 strbuf_addf(&value, "+%s:%s%s", remote_head_points_at->name,
 829                                                 branch_top->buf, head);
 830                         }
 831                         /*
 832                          * otherwise, the next "git fetch" will
 833                          * simply fetch from HEAD without updating
 834                          * any remote-tracking branch, which is what
 835                          * we want.
 836                          */
 837                 } else {
 838                         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top->buf);
 839                 }
 840                 /* Configure the remote */
 841                 if (value.len) {
 842                         strbuf_addf(&key, "remote.%s.fetch", option_origin);
 843                         git_config_set_multivar(key.buf, value.buf, "^$", 0);
 844                         strbuf_reset(&key);
 845
 846                         if (option_mirror) {
 847                                 strbuf_addf(&key, "remote.%s.mirror", option_origin);
 848                                 git_config_set(key.buf, "true");
 849                                 strbuf_reset(&key);
 850                         }
 851                 }
 852         }
 853
 854         strbuf_release(&key);
 855         strbuf_release(&value);
 856 }
 857
 858 static void dissociate_from_references(void)
 859 {
 860         static const char* argv[] = { "repack", "-a", "-d", NULL };
 861         char *alternates = git_pathdup("objects/info/alternates");
 862
 863         if (!access(alternates, F_OK)) {
 864                 if (run_command_v_opt(argv, RUN_GIT_CMD|RUN_COMMAND_NO_STDIN))
 865                         die(_("cannot repack to clean up"));
 866                 if (unlink(alternates) && errno != ENOENT)
 867                         die_errno(_("cannot unlink temporary alternates file"));
 868         }
 869         free(alternates);
 870 }
 871
 872 static int dir_exists(const char *path)
 873 {
 874         struct stat sb;
 875         return !stat(path, &sb);
 876 }
 877
 878 int cmd_clone(int argc, const char **argv, const char *prefix)
 879 {
 880         int is_bundle = 0, is_local;
 881         const char *repo_name, *repo, *work_tree, *git_dir;
 882         char *path, *dir;
 883         int dest_exists;
 884         const struct ref *refs, *remote_head;
 885         const struct ref *remote_head_points_at;
 886         const struct ref *our_head_points_at;
 887         struct ref *mapped_refs;
 888         const struct ref *ref;
 889         struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
 890         struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
 891         struct transport *transport = NULL;
 892         const char *src_ref_prefix = "refs/heads/";
 893         struct remote *remote;
 894         int err = 0, complete_refs_before_fetch = 1;
 895         int submodule_progress;
 896
 897         struct refspec *refspec;
 898         const char *fetch_pattern;
 899
 900         fetch_if_missing = 0;
 901
 902         packet_trace_identity("clone");
 903         argc = parse_options(argc, argv, prefix, builtin_clone_options,
 904                              builtin_clone_usage, 0);
 905
 906         if (argc > 2)
 907                 usage_msg_opt(_("Too many arguments."),
 908                         builtin_clone_usage, builtin_clone_options);
 909
 910         if (argc == 0)
 911                 usage_msg_opt(_("You must specify a repository to clone."),
 912                         builtin_clone_usage, builtin_clone_options);
 913
 914         if (option_depth || option_since || option_not.nr)
 915                 deepen = 1;
 916         if (option_single_branch == -1)
 917                 option_single_branch = deepen ? 1 : 0;
 918
 919         if (option_mirror)
 920                 option_bare = 1;
 921
 922         if (option_bare) {
 923                 if (option_origin)
 924                         die(_("--bare and --origin %s options are incompatible."),
 925                             option_origin);
 926                 if (real_git_dir)
 927                         die(_("--bare and --separate-git-dir are incompatible."));
 928                 option_no_checkout = 1;
 929         }
 930
 931         if (!option_origin)
 932                 option_origin = "origin";
 933
 934         repo_name = argv[0];
 935
 936         path = get_repo_path(repo_name, &is_bundle);
 937         if (path)
 938                 repo = absolute_pathdup(repo_name);
 939         else if (!strchr(repo_name, ':'))
 940                 die(_("repository '%s' does not exist"), repo_name);
 941         else
 942                 repo = repo_name;
 943
 944         /* no need to be strict, transport_set_option() will validate it again */
 945         if (option_depth && atoi(option_depth) < 1)
 946                 die(_("depth %s is not a positive number"), option_depth);
 947
 948         if (argc == 2)
 949                 dir = xstrdup(argv[1]);
 950         else
 951                 dir = guess_dir_name(repo_name, is_bundle, option_bare);
 952         strip_trailing_slashes(dir);
 953
 954         dest_exists = dir_exists(dir);
 955         if (dest_exists && !is_empty_dir(dir))
 956                 die(_("destination path '%s' already exists and is not "
 957                         "an empty directory."), dir);
 958
 959         strbuf_addf(&reflog_msg, "clone: from %s", repo);
 960
 961         if (option_bare)
 962                 work_tree = NULL;
 963         else {
 964                 work_tree = getenv("GIT_WORK_TREE");
 965                 if (work_tree && dir_exists(work_tree))
 966                         die(_("working tree '%s' already exists."), work_tree);
 967         }
 968
 969         if (option_bare || work_tree)
 970                 git_dir = xstrdup(dir);
 971         else {
 972                 work_tree = dir;
 973                 git_dir = mkpathdup("%s/.git", dir);
 974         }
 975
 976         atexit(remove_junk);
 977         sigchain_push_common(remove_junk_on_signal);
 978
 979         if (!option_bare) {
 980                 if (safe_create_leading_directories_const(work_tree) < 0)
 981                         die_errno(_("could not create leading directories of '%s'"),
 982                                   work_tree);
 983                 if (dest_exists)
 984                         junk_work_tree_flags |= REMOVE_DIR_KEEP_TOPLEVEL;
 985                 else if (mkdir(work_tree, 0777))
 986                         die_errno(_("could not create work tree dir '%s'"),
 987                                   work_tree);
 988                 junk_work_tree = work_tree;
 989                 set_git_work_tree(work_tree);
 990         }
 991
 992         if (real_git_dir) {
 993                 if (dir_exists(real_git_dir))
 994                         junk_git_dir_flags |= REMOVE_DIR_KEEP_TOPLEVEL;
 995                 junk_git_dir = real_git_dir;
 996         } else {
 997                 if (dest_exists)
 998                         junk_git_dir_flags |= REMOVE_DIR_KEEP_TOPLEVEL;
 999                 junk_git_dir = git_dir;
1000         }
1001         if (safe_create_leading_directories_const(git_dir) < 0)
1002                 die(_("could not create leading directories of '%s'"), git_dir);
1003
1004         if (0 <= option_verbosity) {
1005                 if (option_bare)
1006                         fprintf(stderr, _("Cloning into bare repository '%s'...\n"), dir);
1007                 else
1008                         fprintf(stderr, _("Cloning into '%s'...\n"), dir);
1009         }
1010
1011         if (option_recurse_submodules.nr > 0) {
1012                 struct string_list_item *item;
1013                 struct strbuf sb = STRBUF_INIT;
1014
1015                 /* remove duplicates */
1016                 string_list_sort(&option_recurse_submodules);
1017                 string_list_remove_duplicates(&option_recurse_submodules, 0);
1018
1019                 /*
1020                  * NEEDSWORK: In a multi-working-tree world, this needs to be
1021                  * set in the per-worktree config.
1022                  */
1023                 for_each_string_list_item(item, &option_recurse_submodules) {
1024                         strbuf_addf(&sb, "submodule.active=%s",
1025                                     item->string);
1026                         string_list_append(&option_config,
1027                                            strbuf_detach(&sb, NULL));
1028                 }
1029
1030                 if (option_required_reference.nr &&
1031                     option_optional_reference.nr)
1032                         die(_("clone --recursive is not compatible with "
1033                               "both --reference and --reference-if-able"));
1034                 else if (option_required_reference.nr) {
1035                         string_list_append(&option_config,
1036                                 "submodule.alternateLocation=superproject");
1037                         string_list_append(&option_config,
1038                                 "submodule.alternateErrorStrategy=die");
1039                 } else if (option_optional_reference.nr) {
1040                         string_list_append(&option_config,
1041                                 "submodule.alternateLocation=superproject");
1042                         string_list_append(&option_config,
1043                                 "submodule.alternateErrorStrategy=info");
1044                 }
1045         }
1046
1047         init_db(git_dir, real_git_dir, option_template, INIT_DB_QUIET);
1048
1049         if (real_git_dir)
1050                 git_dir = real_git_dir;
1051
1052         write_config(&option_config);
1053
1054         git_config(git_default_config, NULL);
1055
1056         if (option_bare) {
1057                 if (option_mirror)
1058                         src_ref_prefix = "refs/";
1059                 strbuf_addstr(&branch_top, src_ref_prefix);
1060
1061                 git_config_set("core.bare", "true");
1062         } else {
1063                 strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
1064         }
1065
1066         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top.buf);
1067         strbuf_addf(&key, "remote.%s.url", option_origin);
1068         git_config_set(key.buf, repo);
1069         strbuf_reset(&key);
1070
1071         if (option_no_tags) {
1072                 strbuf_addf(&key, "remote.%s.tagOpt", option_origin);
1073                 git_config_set(key.buf, "--no-tags");
1074                 strbuf_reset(&key);
1075         }
1076
1077         if (option_required_reference.nr || option_optional_reference.nr)
1078                 setup_reference();
1079
1080         fetch_pattern = value.buf;
1081         refspec = parse_fetch_refspec(1, &fetch_pattern);
1082
1083         strbuf_reset(&value);
1084
1085         remote = remote_get(option_origin);
1086         transport = transport_get(remote, remote->url[0]);
1087         transport_set_verbosity(transport, option_verbosity, option_progress);
1088         transport->family = family;
1089
1090         path = get_repo_path(remote->url[0], &is_bundle);
1091         is_local = option_local != 0 && path && !is_bundle;
1092         if (is_local) {
1093                 if (option_depth)
1094                         warning(_("--depth is ignored in local clones; use file:// instead."));
1095                 if (option_since)
1096                         warning(_("--shallow-since is ignored in local clones; use file:// instead."));
1097                 if (option_not.nr)
1098                         warning(_("--shallow-exclude is ignored in local clones; use file:// instead."));
1099                 if (filter_options.choice)
1100                         warning(_("--filter is ignored in local clones; use file:// instead."));
1101                 if (!access(mkpath("%s/shallow", path), F_OK)) {
1102                         if (option_local > 0)
1103                                 warning(_("source repository is shallow, ignoring --local"));
1104                         is_local = 0;
1105                 }
1106         }
1107         if (option_local > 0 && !is_local)
1108                 warning(_("--local is ignored"));
1109         transport->cloning = 1;
1110
1111         transport_set_option(transport, TRANS_OPT_KEEP, "yes");
1112
1113         if (option_depth)
1114                 transport_set_option(transport, TRANS_OPT_DEPTH,
1115                                      option_depth);
1116         if (option_since)
1117                 transport_set_option(transport, TRANS_OPT_DEEPEN_SINCE,
1118                                      option_since);
1119         if (option_not.nr)
1120                 transport_set_option(transport, TRANS_OPT_DEEPEN_NOT,
1121                                      (const char *)&option_not);
1122         if (option_single_branch)
1123                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
1124
1125         if (option_upload_pack)
1126                 transport_set_option(transport, TRANS_OPT_UPLOADPACK,
1127                                      option_upload_pack);
1128
1129         if (filter_options.choice) {
1130                 transport_set_option(transport, TRANS_OPT_LIST_OBJECTS_FILTER,
1131                                      filter_options.filter_spec);
1132                 transport_set_option(transport, TRANS_OPT_FROM_PROMISOR, "1");
1133         }
1134
1135         if (transport->smart_options && !deepen && !filter_options.choice)
1136                 transport->smart_options->check_self_contained_and_connected = 1;
1137
1138         refs = transport_get_remote_refs(transport);
1139
1140         if (refs) {
1141                 mapped_refs = wanted_peer_refs(refs, refspec);
1142                 /*
1143                  * transport_get_remote_refs() may return refs with null sha-1
1144                  * in mapped_refs (see struct transport->get_refs_list
1145                  * comment). In that case we need fetch it early because
1146                  * remote_head code below relies on it.
1147                  *
1148                  * for normal clones, transport_get_remote_refs() should
1149                  * return reliable ref set, we can delay cloning until after
1150                  * remote HEAD check.
1151                  */
1152                 for (ref = refs; ref; ref = ref->next)
1153                         if (is_null_oid(&ref->old_oid)) {
1154                                 complete_refs_before_fetch = 0;
1155                                 break;
1156                         }
1157
1158                 if (!is_local && !complete_refs_before_fetch)
1159                         transport_fetch_refs(transport, mapped_refs);
1160
1161                 remote_head = find_ref_by_name(refs, "HEAD");
1162                 remote_head_points_at =
1163                         guess_remote_head(remote_head, mapped_refs, 0);
1164
1165                 if (option_branch) {
1166                         our_head_points_at =
1167                                 find_remote_branch(mapped_refs, option_branch);
1168
1169                         if (!our_head_points_at)
1170                                 die(_("Remote branch %s not found in upstream %s"),
1171                                     option_branch, option_origin);
1172                 }
1173                 else
1174                         our_head_points_at = remote_head_points_at;
1175         }
1176         else {
1177                 if (option_branch)
1178                         die(_("Remote branch %s not found in upstream %s"),
1179                                         option_branch, option_origin);
1180
1181                 warning(_("You appear to have cloned an empty repository."));
1182                 mapped_refs = NULL;
1183                 our_head_points_at = NULL;
1184                 remote_head_points_at = NULL;
1185                 remote_head = NULL;
1186                 option_no_checkout = 1;
1187                 if (!option_bare)
1188                         install_branch_config(0, "master", option_origin,
1189                                               "refs/heads/master");
1190         }
1191
1192         write_refspec_config(src_ref_prefix, our_head_points_at,
1193                         remote_head_points_at, &branch_top);
1194
1195         if (filter_options.choice)
1196                 partial_clone_register("origin", &filter_options);
1197
1198         if (is_local)
1199                 clone_local(path, git_dir);
1200         else if (refs && complete_refs_before_fetch)
1201                 transport_fetch_refs(transport, mapped_refs);
1202
1203         update_remote_refs(refs, mapped_refs, remote_head_points_at,
1204                            branch_top.buf, reflog_msg.buf, transport,
1205                            !is_local && !filter_options.choice);
1206
1207         update_head(our_head_points_at, remote_head, reflog_msg.buf);
1208
1209         /*
1210          * We want to show progress for recursive submodule clones iff
1211          * we did so for the main clone. But only the transport knows
1212          * the final decision for this flag, so we need to rescue the value
1213          * before we free the transport.
1214          */
1215         submodule_progress = transport->progress;
1216
1217         transport_unlock_pack(transport);
1218         transport_disconnect(transport);
1219
1220         if (option_dissociate) {
1221                 close_all_packs(the_repository->objects);
1222                 dissociate_from_references();
1223         }
1224
1225         junk_mode = JUNK_LEAVE_REPO;
1226         fetch_if_missing = 1;
1227         err = checkout(submodule_progress);
1228
1229         strbuf_release(&reflog_msg);
1230         strbuf_release(&branch_top);
1231         strbuf_release(&key);
1232         strbuf_release(&value);
1233         junk_mode = JUNK_LEAVE_ALL;
1234
1235         free(refspec);
1236         return err;
1237 }