builtin/clone.c

   1 /*
   2  * Builtin "git clone"
   3  *
   4  * Copyright (c) 2007 Kristian Høgsberg <krh@redhat.com>,
   5  *               2008 Daniel Barkalow <barkalow@iabervon.org>
   6  * Based on git-commit.sh by Junio C Hamano and Linus Torvalds
   7  *
   8  * Clone a repository into a different directory that does not yet exist.
   9  */
  10
  11 #include "builtin.h"
  12 #include "lockfile.h"
  13 #include "parse-options.h"
  14 #include "fetch-pack.h"
  15 #include "refs.h"
  16 #include "tree.h"
  17 #include "tree-walk.h"
  18 #include "unpack-trees.h"
  19 #include "transport.h"
  20 #include "strbuf.h"
  21 #include "dir.h"
  22 #include "sigchain.h"
  23 #include "branch.h"
  24 #include "remote.h"
  25 #include "run-command.h"
  26 #include "connected.h"
  27
  28 /*
  29  * Overall FIXMEs:
  30  *  - respect DB_ENVIRONMENT for .git/objects.
  31  *
  32  * Implementation notes:
  33  *  - dropping use-separate-remote and no-separate-remote compatibility
  34  *
  35  */
  36 static const char * const builtin_clone_usage[] = {
  37         N_("git clone [<options>] [--] <repo> [<dir>]"),
  38         NULL
  39 };
  40
  41 static int option_no_checkout, option_bare, option_mirror, option_single_branch = -1;
  42 static int option_local = -1, option_no_hardlinks, option_shared, option_recursive;
  43 static int option_shallow_submodules;
  44 static int deepen;
  45 static char *option_template, *option_depth, *option_since;
  46 static char *option_origin = NULL;
  47 static char *option_branch = NULL;
  48 static struct string_list option_not = STRING_LIST_INIT_NODUP;
  49 static const char *real_git_dir;
  50 static char *option_upload_pack = "git-upload-pack";
  51 static int option_verbosity;
  52 static int option_progress = -1;
  53 static enum transport_family family;
  54 static struct string_list option_config = STRING_LIST_INIT_NODUP;
  55 static struct string_list option_required_reference = STRING_LIST_INIT_NODUP;
  56 static struct string_list option_optional_reference = STRING_LIST_INIT_NODUP;
  57 static int option_dissociate;
  58 static int max_jobs = -1;
  59
  60 static struct option builtin_clone_options[] = {
  61         OPT__VERBOSITY(&option_verbosity),
  62         OPT_BOOL(0, "progress", &option_progress,
  63                  N_("force progress reporting")),
  64         OPT_BOOL('n', "no-checkout", &option_no_checkout,
  65                  N_("don't create a checkout")),
  66         OPT_BOOL(0, "bare", &option_bare, N_("create a bare repository")),
  67         OPT_HIDDEN_BOOL(0, "naked", &option_bare,
  68                         N_("create a bare repository")),
  69         OPT_BOOL(0, "mirror", &option_mirror,
  70                  N_("create a mirror repository (implies bare)")),
  71         OPT_BOOL('l', "local", &option_local,
  72                 N_("to clone from a local repository")),
  73         OPT_BOOL(0, "no-hardlinks", &option_no_hardlinks,
  74                     N_("don't use local hardlinks, always copy")),
  75         OPT_BOOL('s', "shared", &option_shared,
  76                     N_("setup as shared repository")),
  77         OPT_BOOL(0, "recursive", &option_recursive,
  78                     N_("initialize submodules in the clone")),
  79         OPT_BOOL(0, "recurse-submodules", &option_recursive,
  80                     N_("initialize submodules in the clone")),
  81         OPT_INTEGER('j', "jobs", &max_jobs,
  82                     N_("number of submodules cloned in parallel")),
  83         OPT_STRING(0, "template", &option_template, N_("template-directory"),
  84                    N_("directory from which templates will be used")),
  85         OPT_STRING_LIST(0, "reference", &option_required_reference, N_("repo"),
  86                         N_("reference repository")),
  87         OPT_STRING_LIST(0, "reference-if-able", &option_optional_reference,
  88                         N_("repo"), N_("reference repository")),
  89         OPT_BOOL(0, "dissociate", &option_dissociate,
  90                  N_("use --reference only while cloning")),
  91         OPT_STRING('o', "origin", &option_origin, N_("name"),
  92                    N_("use <name> instead of 'origin' to track upstream")),
  93         OPT_STRING('b', "branch", &option_branch, N_("branch"),
  94                    N_("checkout <branch> instead of the remote's HEAD")),
  95         OPT_STRING('u', "upload-pack", &option_upload_pack, N_("path"),
  96                    N_("path to git-upload-pack on the remote")),
  97         OPT_STRING(0, "depth", &option_depth, N_("depth"),
  98                     N_("create a shallow clone of that depth")),
  99         OPT_STRING(0, "shallow-since", &option_since, N_("time"),
 100                     N_("create a shallow clone since a specific time")),
 101         OPT_STRING_LIST(0, "shallow-exclude", &option_not, N_("revision"),
 102                         N_("deepen history of shallow clone, excluding rev")),
 103         OPT_BOOL(0, "single-branch", &option_single_branch,
 104                     N_("clone only one branch, HEAD or --branch")),
 105         OPT_BOOL(0, "shallow-submodules", &option_shallow_submodules,
 106                     N_("any cloned submodules will be shallow")),
 107         OPT_STRING(0, "separate-git-dir", &real_git_dir, N_("gitdir"),
 108                    N_("separate git dir from working tree")),
 109         OPT_STRING_LIST('c', "config", &option_config, N_("key=value"),
 110                         N_("set config inside the new repository")),
 111         OPT_SET_INT('4', "ipv4", &family, N_("use IPv4 addresses only"),
 112                         TRANSPORT_FAMILY_IPV4),
 113         OPT_SET_INT('6', "ipv6", &family, N_("use IPv6 addresses only"),
 114                         TRANSPORT_FAMILY_IPV6),
 115         OPT_END()
 116 };
 117
 118 static const char *get_repo_path_1(struct strbuf *path, int *is_bundle)
 119 {
 120         static char *suffix[] = { "/.git", "", ".git/.git", ".git" };
 121         static char *bundle_suffix[] = { ".bundle", "" };
 122         size_t baselen = path->len;
 123         struct stat st;
 124         int i;
 125
 126         for (i = 0; i < ARRAY_SIZE(suffix); i++) {
 127                 strbuf_setlen(path, baselen);
 128                 strbuf_addstr(path, suffix[i]);
 129                 if (stat(path->buf, &st))
 130                         continue;
 131                 if (S_ISDIR(st.st_mode) && is_git_directory(path->buf)) {
 132                         *is_bundle = 0;
 133                         return path->buf;
 134                 } else if (S_ISREG(st.st_mode) && st.st_size > 8) {
 135                         /* Is it a "gitfile"? */
 136                         char signature[8];
 137                         const char *dst;
 138                         int len, fd = open(path->buf, O_RDONLY);
 139                         if (fd < 0)
 140                                 continue;
 141                         len = read_in_full(fd, signature, 8);
 142                         close(fd);
 143                         if (len != 8 || strncmp(signature, "gitdir: ", 8))
 144                                 continue;
 145                         dst = read_gitfile(path->buf);
 146                         if (dst) {
 147                                 *is_bundle = 0;
 148                                 return dst;
 149                         }
 150                 }
 151         }
 152
 153         for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
 154                 strbuf_setlen(path, baselen);
 155                 strbuf_addstr(path, bundle_suffix[i]);
 156                 if (!stat(path->buf, &st) && S_ISREG(st.st_mode)) {
 157                         *is_bundle = 1;
 158                         return path->buf;
 159                 }
 160         }
 161
 162         return NULL;
 163 }
 164
 165 static char *get_repo_path(const char *repo, int *is_bundle)
 166 {
 167         struct strbuf path = STRBUF_INIT;
 168         const char *raw;
 169         char *canon;
 170
 171         strbuf_addstr(&path, repo);
 172         raw = get_repo_path_1(&path, is_bundle);
 173         canon = raw ? absolute_pathdup(raw) : NULL;
 174         strbuf_release(&path);
 175         return canon;
 176 }
 177
 178 static char *guess_dir_name(const char *repo, int is_bundle, int is_bare)
 179 {
 180         const char *end = repo + strlen(repo), *start, *ptr;
 181         size_t len;
 182         char *dir;
 183
 184         /*
 185          * Skip scheme.
 186          */
 187         start = strstr(repo, "://");
 188         if (start == NULL)
 189                 start = repo;
 190         else
 191                 start += 3;
 192
 193         /*
 194          * Skip authentication data. The stripping does happen
 195          * greedily, such that we strip up to the last '@' inside
 196          * the host part.
 197          */
 198         for (ptr = start; ptr < end && !is_dir_sep(*ptr); ptr++) {
 199                 if (*ptr == '@')
 200                         start = ptr + 1;
 201         }
 202
 203         /*
 204          * Strip trailing spaces, slashes and /.git
 205          */
 206         while (start < end && (is_dir_sep(end[-1]) || isspace(end[-1])))
 207                 end--;
 208         if (end - start > 5 && is_dir_sep(end[-5]) &&
 209             !strncmp(end - 4, ".git", 4)) {
 210                 end -= 5;
 211                 while (start < end && is_dir_sep(end[-1]))
 212                         end--;
 213         }
 214
 215         /*
 216          * Strip trailing port number if we've got only a
 217          * hostname (that is, there is no dir separator but a
 218          * colon). This check is required such that we do not
 219          * strip URI's like '/foo/bar:2222.git', which should
 220          * result in a dir '2222' being guessed due to backwards
 221          * compatibility.
 222          */
 223         if (memchr(start, '/', end - start) == NULL
 224             && memchr(start, ':', end - start) != NULL) {
 225                 ptr = end;
 226                 while (start < ptr && isdigit(ptr[-1]) && ptr[-1] != ':')
 227                         ptr--;
 228                 if (start < ptr && ptr[-1] == ':')
 229                         end = ptr - 1;
 230         }
 231
 232         /*
 233          * Find last component. To remain backwards compatible we
 234          * also regard colons as path separators, such that
 235          * cloning a repository 'foo:bar.git' would result in a
 236          * directory 'bar' being guessed.
 237          */
 238         ptr = end;
 239         while (start < ptr && !is_dir_sep(ptr[-1]) && ptr[-1] != ':')
 240                 ptr--;
 241         start = ptr;
 242
 243         /*
 244          * Strip .{bundle,git}.
 245          */
 246         len = end - start;
 247         strip_suffix_mem(start, &len, is_bundle ? ".bundle" : ".git");
 248
 249         if (!len || (len == 1 && *start == '/'))
 250                 die(_("No directory name could be guessed.\n"
 251                       "Please specify a directory on the command line"));
 252
 253         if (is_bare)
 254                 dir = xstrfmt("%.*s.git", (int)len, start);
 255         else
 256                 dir = xstrndup(start, len);
 257         /*
 258          * Replace sequences of 'control' characters and whitespace
 259          * with one ascii space, remove leading and trailing spaces.
 260          */
 261         if (*dir) {
 262                 char *out = dir;
 263                 int prev_space = 1 /* strip leading whitespace */;
 264                 for (end = dir; *end; ++end) {
 265                         char ch = *end;
 266                         if ((unsigned char)ch < '\x20')
 267                                 ch = '\x20';
 268                         if (isspace(ch)) {
 269                                 if (prev_space)
 270                                         continue;
 271                                 prev_space = 1;
 272                         } else
 273                                 prev_space = 0;
 274                         *out++ = ch;
 275                 }
 276                 *out = '\0';
 277                 if (out > dir && prev_space)
 278                         out[-1] = '\0';
 279         }
 280         return dir;
 281 }
 282
 283 static void strip_trailing_slashes(char *dir)
 284 {
 285         char *end = dir + strlen(dir);
 286
 287         while (dir < end - 1 && is_dir_sep(end[-1]))
 288                 end--;
 289         *end = '\0';
 290 }
 291
 292 static int add_one_reference(struct string_list_item *item, void *cb_data)
 293 {
 294         struct strbuf err = STRBUF_INIT;
 295         int *required = cb_data;
 296         char *ref_git = compute_alternate_path(item->string, &err);
 297
 298         if (!ref_git) {
 299                 if (*required)
 300                         die("%s", err.buf);
 301                 else
 302                         fprintf(stderr,
 303                                 _("info: Could not add alternate for '%s': %s\n"),
 304                                 item->string, err.buf);
 305         } else {
 306                 struct strbuf sb = STRBUF_INIT;
 307                 strbuf_addf(&sb, "%s/objects", ref_git);
 308                 add_to_alternates_file(sb.buf);
 309                 strbuf_release(&sb);
 310         }
 311
 312         strbuf_release(&err);
 313         free(ref_git);
 314         return 0;
 315 }
 316
 317 static void setup_reference(void)
 318 {
 319         int required = 1;
 320         for_each_string_list(&option_required_reference,
 321                              add_one_reference, &required);
 322         required = 0;
 323         for_each_string_list(&option_optional_reference,
 324                              add_one_reference, &required);
 325 }
 326
 327 static void copy_alternates(struct strbuf *src, struct strbuf *dst,
 328                             const char *src_repo)
 329 {
 330         /*
 331          * Read from the source objects/info/alternates file
 332          * and copy the entries to corresponding file in the
 333          * destination repository with add_to_alternates_file().
 334          * Both src and dst have "$path/objects/info/alternates".
 335          *
 336          * Instead of copying bit-for-bit from the original,
 337          * we need to append to existing one so that the already
 338          * created entry via "clone -s" is not lost, and also
 339          * to turn entries with paths relative to the original
 340          * absolute, so that they can be used in the new repository.
 341          */
 342         FILE *in = fopen(src->buf, "r");
 343         struct strbuf line = STRBUF_INIT;
 344
 345         while (strbuf_getline(&line, in) != EOF) {
 346                 char *abs_path;
 347                 if (!line.len || line.buf[0] == '#')
 348                         continue;
 349                 if (is_absolute_path(line.buf)) {
 350                         add_to_alternates_file(line.buf);
 351                         continue;
 352                 }
 353                 abs_path = mkpathdup("%s/objects/%s", src_repo, line.buf);
 354                 if (!normalize_path_copy(abs_path, abs_path))
 355                         add_to_alternates_file(abs_path);
 356                 else
 357                         warning("skipping invalid relative alternate: %s/%s",
 358                                 src_repo, line.buf);
 359                 free(abs_path);
 360         }
 361         strbuf_release(&line);
 362         fclose(in);
 363 }
 364
 365 static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
 366                                    const char *src_repo, int src_baselen)
 367 {
 368         struct dirent *de;
 369         struct stat buf;
 370         int src_len, dest_len;
 371         DIR *dir;
 372
 373         dir = opendir(src->buf);
 374         if (!dir)
 375                 die_errno(_("failed to open '%s'"), src->buf);
 376
 377         if (mkdir(dest->buf, 0777)) {
 378                 if (errno != EEXIST)
 379                         die_errno(_("failed to create directory '%s'"), dest->buf);
 380                 else if (stat(dest->buf, &buf))
 381                         die_errno(_("failed to stat '%s'"), dest->buf);
 382                 else if (!S_ISDIR(buf.st_mode))
 383                         die(_("%s exists and is not a directory"), dest->buf);
 384         }
 385
 386         strbuf_addch(src, '/');
 387         src_len = src->len;
 388         strbuf_addch(dest, '/');
 389         dest_len = dest->len;
 390
 391         while ((de = readdir(dir)) != NULL) {
 392                 strbuf_setlen(src, src_len);
 393                 strbuf_addstr(src, de->d_name);
 394                 strbuf_setlen(dest, dest_len);
 395                 strbuf_addstr(dest, de->d_name);
 396                 if (stat(src->buf, &buf)) {
 397                         warning (_("failed to stat %s\n"), src->buf);
 398                         continue;
 399                 }
 400                 if (S_ISDIR(buf.st_mode)) {
 401                         if (de->d_name[0] != '.')
 402                                 copy_or_link_directory(src, dest,
 403                                                        src_repo, src_baselen);
 404                         continue;
 405                 }
 406
 407                 /* Files that cannot be copied bit-for-bit... */
 408                 if (!strcmp(src->buf + src_baselen, "/info/alternates")) {
 409                         copy_alternates(src, dest, src_repo);
 410                         continue;
 411                 }
 412
 413                 if (unlink(dest->buf) && errno != ENOENT)
 414                         die_errno(_("failed to unlink '%s'"), dest->buf);
 415                 if (!option_no_hardlinks) {
 416                         if (!link(src->buf, dest->buf))
 417                                 continue;
 418                         if (option_local > 0)
 419                                 die_errno(_("failed to create link '%s'"), dest->buf);
 420                         option_no_hardlinks = 1;
 421                 }
 422                 if (copy_file_with_time(dest->buf, src->buf, 0666))
 423                         die_errno(_("failed to copy file to '%s'"), dest->buf);
 424         }
 425         closedir(dir);
 426 }
 427
 428 static void clone_local(const char *src_repo, const char *dest_repo)
 429 {
 430         if (option_shared) {
 431                 struct strbuf alt = STRBUF_INIT;
 432                 strbuf_addf(&alt, "%s/objects", src_repo);
 433                 add_to_alternates_file(alt.buf);
 434                 strbuf_release(&alt);
 435         } else {
 436                 struct strbuf src = STRBUF_INIT;
 437                 struct strbuf dest = STRBUF_INIT;
 438                 get_common_dir(&src, src_repo);
 439                 get_common_dir(&dest, dest_repo);
 440                 strbuf_addstr(&src, "/objects");
 441                 strbuf_addstr(&dest, "/objects");
 442                 copy_or_link_directory(&src, &dest, src_repo, src.len);
 443                 strbuf_release(&src);
 444                 strbuf_release(&dest);
 445         }
 446
 447         if (0 <= option_verbosity)
 448                 fprintf(stderr, _("done.\n"));
 449 }
 450
 451 static const char *junk_work_tree;
 452 static const char *junk_git_dir;
 453 static enum {
 454         JUNK_LEAVE_NONE,
 455         JUNK_LEAVE_REPO,
 456         JUNK_LEAVE_ALL
 457 } junk_mode = JUNK_LEAVE_NONE;
 458
 459 static const char junk_leave_repo_msg[] =
 460 N_("Clone succeeded, but checkout failed.\n"
 461    "You can inspect what was checked out with 'git status'\n"
 462    "and retry the checkout with 'git checkout -f HEAD'\n");
 463
 464 static void remove_junk(void)
 465 {
 466         struct strbuf sb = STRBUF_INIT;
 467
 468         switch (junk_mode) {
 469         case JUNK_LEAVE_REPO:
 470                 warning("%s", _(junk_leave_repo_msg));
 471                 /* fall-through */
 472         case JUNK_LEAVE_ALL:
 473                 return;
 474         default:
 475                 /* proceed to removal */
 476                 break;
 477         }
 478
 479         if (junk_git_dir) {
 480                 strbuf_addstr(&sb, junk_git_dir);
 481                 remove_dir_recursively(&sb, 0);
 482                 strbuf_reset(&sb);
 483         }
 484         if (junk_work_tree) {
 485                 strbuf_addstr(&sb, junk_work_tree);
 486                 remove_dir_recursively(&sb, 0);
 487                 strbuf_reset(&sb);
 488         }
 489 }
 490
 491 static void remove_junk_on_signal(int signo)
 492 {
 493         remove_junk();
 494         sigchain_pop(signo);
 495         raise(signo);
 496 }
 497
 498 static struct ref *find_remote_branch(const struct ref *refs, const char *branch)
 499 {
 500         struct ref *ref;
 501         struct strbuf head = STRBUF_INIT;
 502         strbuf_addstr(&head, "refs/heads/");
 503         strbuf_addstr(&head, branch);
 504         ref = find_ref_by_name(refs, head.buf);
 505         strbuf_release(&head);
 506
 507         if (ref)
 508                 return ref;
 509
 510         strbuf_addstr(&head, "refs/tags/");
 511         strbuf_addstr(&head, branch);
 512         ref = find_ref_by_name(refs, head.buf);
 513         strbuf_release(&head);
 514
 515         return ref;
 516 }
 517
 518 static struct ref *wanted_peer_refs(const struct ref *refs,
 519                 struct refspec *refspec)
 520 {
 521         struct ref *head = copy_ref(find_ref_by_name(refs, "HEAD"));
 522         struct ref *local_refs = head;
 523         struct ref **tail = head ? &head->next : &local_refs;
 524
 525         if (option_single_branch) {
 526                 struct ref *remote_head = NULL;
 527
 528                 if (!option_branch)
 529                         remote_head = guess_remote_head(head, refs, 0);
 530                 else {
 531                         local_refs = NULL;
 532                         tail = &local_refs;
 533                         remote_head = copy_ref(find_remote_branch(refs, option_branch));
 534                 }
 535
 536                 if (!remote_head && option_branch)
 537                         warning(_("Could not find remote branch %s to clone."),
 538                                 option_branch);
 539                 else {
 540                         get_fetch_map(remote_head, refspec, &tail, 0);
 541
 542                         /* if --branch=tag, pull the requested tag explicitly */
 543                         get_fetch_map(remote_head, tag_refspec, &tail, 0);
 544                 }
 545         } else
 546                 get_fetch_map(refs, refspec, &tail, 0);
 547
 548         if (!option_mirror && !option_single_branch)
 549                 get_fetch_map(refs, tag_refspec, &tail, 0);
 550
 551         return local_refs;
 552 }
 553
 554 static void write_remote_refs(const struct ref *local_refs)
 555 {
 556         const struct ref *r;
 557
 558         struct ref_transaction *t;
 559         struct strbuf err = STRBUF_INIT;
 560
 561         t = ref_transaction_begin(&err);
 562         if (!t)
 563                 die("%s", err.buf);
 564
 565         for (r = local_refs; r; r = r->next) {
 566                 if (!r->peer_ref)
 567                         continue;
 568                 if (ref_transaction_create(t, r->peer_ref->name, r->old_oid.hash,
 569                                            0, NULL, &err))
 570                         die("%s", err.buf);
 571         }
 572
 573         if (initial_ref_transaction_commit(t, &err))
 574                 die("%s", err.buf);
 575
 576         strbuf_release(&err);
 577         ref_transaction_free(t);
 578 }
 579
 580 static void write_followtags(const struct ref *refs, const char *msg)
 581 {
 582         const struct ref *ref;
 583         for (ref = refs; ref; ref = ref->next) {
 584                 if (!starts_with(ref->name, "refs/tags/"))
 585                         continue;
 586                 if (ends_with(ref->name, "^{}"))
 587                         continue;
 588                 if (!has_object_file(&ref->old_oid))
 589                         continue;
 590                 update_ref(msg, ref->name, ref->old_oid.hash,
 591                            NULL, 0, UPDATE_REFS_DIE_ON_ERR);
 592         }
 593 }
 594
 595 static int iterate_ref_map(void *cb_data, unsigned char sha1[20])
 596 {
 597         struct ref **rm = cb_data;
 598         struct ref *ref = *rm;
 599
 600         /*
 601          * Skip anything missing a peer_ref, which we are not
 602          * actually going to write a ref for.
 603          */
 604         while (ref && !ref->peer_ref)
 605                 ref = ref->next;
 606         /* Returning -1 notes "end of list" to the caller. */
 607         if (!ref)
 608                 return -1;
 609
 610         hashcpy(sha1, ref->old_oid.hash);
 611         *rm = ref->next;
 612         return 0;
 613 }
 614
 615 static void update_remote_refs(const struct ref *refs,
 616                                const struct ref *mapped_refs,
 617                                const struct ref *remote_head_points_at,
 618                                const char *branch_top,
 619                                const char *msg,
 620                                struct transport *transport,
 621                                int check_connectivity)
 622 {
 623         const struct ref *rm = mapped_refs;
 624
 625         if (check_connectivity) {
 626                 struct check_connected_options opt = CHECK_CONNECTED_INIT;
 627
 628                 opt.transport = transport;
 629                 opt.progress = transport->progress;
 630
 631                 if (check_connected(iterate_ref_map, &rm, &opt))
 632                         die(_("remote did not send all necessary objects"));
 633         }
 634
 635         if (refs) {
 636                 write_remote_refs(mapped_refs);
 637                 if (option_single_branch)
 638                         write_followtags(refs, msg);
 639         }
 640
 641         if (remote_head_points_at && !option_bare) {
 642                 struct strbuf head_ref = STRBUF_INIT;
 643                 strbuf_addstr(&head_ref, branch_top);
 644                 strbuf_addstr(&head_ref, "HEAD");
 645                 if (create_symref(head_ref.buf,
 646                                   remote_head_points_at->peer_ref->name,
 647                                   msg) < 0)
 648                         die(_("unable to update %s"), head_ref.buf);
 649                 strbuf_release(&head_ref);
 650         }
 651 }
 652
 653 static void update_head(const struct ref *our, const struct ref *remote,
 654                         const char *msg)
 655 {
 656         const char *head;
 657         if (our && skip_prefix(our->name, "refs/heads/", &head)) {
 658                 /* Local default branch link */
 659                 if (create_symref("HEAD", our->name, NULL) < 0)
 660                         die(_("unable to update HEAD"));
 661                 if (!option_bare) {
 662                         update_ref(msg, "HEAD", our->old_oid.hash, NULL, 0,
 663                                    UPDATE_REFS_DIE_ON_ERR);
 664                         install_branch_config(0, head, option_origin, our->name);
 665                 }
 666         } else if (our) {
 667                 struct commit *c = lookup_commit_reference(our->old_oid.hash);
 668                 /* --branch specifies a non-branch (i.e. tags), detach HEAD */
 669                 update_ref(msg, "HEAD", c->object.oid.hash,
 670                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
 671         } else if (remote) {
 672                 /*
 673                  * We know remote HEAD points to a non-branch, or
 674                  * HEAD points to a branch but we don't know which one.
 675                  * Detach HEAD in all these cases.
 676                  */
 677                 update_ref(msg, "HEAD", remote->old_oid.hash,
 678                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
 679         }
 680 }
 681
 682 static int checkout(int submodule_progress)
 683 {
 684         unsigned char sha1[20];
 685         char *head;
 686         struct lock_file *lock_file;
 687         struct unpack_trees_options opts;
 688         struct tree *tree;
 689         struct tree_desc t;
 690         int err = 0;
 691
 692         if (option_no_checkout)
 693                 return 0;
 694
 695         head = resolve_refdup("HEAD", RESOLVE_REF_READING, sha1, NULL);
 696         if (!head) {
 697                 warning(_("remote HEAD refers to nonexistent ref, "
 698                           "unable to checkout.\n"));
 699                 return 0;
 700         }
 701         if (!strcmp(head, "HEAD")) {
 702                 if (advice_detached_head)
 703                         detach_advice(sha1_to_hex(sha1));
 704         } else {
 705                 if (!starts_with(head, "refs/heads/"))
 706                         die(_("HEAD not found below refs/heads!"));
 707         }
 708         free(head);
 709
 710         /* We need to be in the new work tree for the checkout */
 711         setup_work_tree();
 712
 713         lock_file = xcalloc(1, sizeof(struct lock_file));
 714         hold_locked_index(lock_file, LOCK_DIE_ON_ERROR);
 715
 716         memset(&opts, 0, sizeof opts);
 717         opts.update = 1;
 718         opts.merge = 1;
 719         opts.fn = oneway_merge;
 720         opts.verbose_update = (option_verbosity >= 0);
 721         opts.src_index = &the_index;
 722         opts.dst_index = &the_index;
 723
 724         tree = parse_tree_indirect(sha1);
 725         parse_tree(tree);
 726         init_tree_desc(&t, tree->buffer, tree->size);
 727         if (unpack_trees(1, &t, &opts) < 0)
 728                 die(_("unable to checkout working tree"));
 729
 730         if (write_locked_index(&the_index, lock_file, COMMIT_LOCK))
 731                 die(_("unable to write new index file"));
 732
 733         err |= run_hook_le(NULL, "post-checkout", sha1_to_hex(null_sha1),
 734                            sha1_to_hex(sha1), "1", NULL);
 735
 736         if (!err && option_recursive) {
 737                 struct argv_array args = ARGV_ARRAY_INIT;
 738                 argv_array_pushl(&args, "submodule", "update", "--init", "--recursive", NULL);
 739
 740                 if (option_shallow_submodules == 1)
 741                         argv_array_push(&args, "--depth=1");
 742
 743                 if (max_jobs != -1)
 744                         argv_array_pushf(&args, "--jobs=%d", max_jobs);
 745
 746                 if (submodule_progress)
 747                         argv_array_push(&args, "--progress");
 748
 749                 err = run_command_v_opt(args.argv, RUN_GIT_CMD);
 750                 argv_array_clear(&args);
 751         }
 752
 753         return err;
 754 }
 755
 756 static int write_one_config(const char *key, const char *value, void *data)
 757 {
 758         return git_config_set_multivar_gently(key, value ? value : "true", "^$", 0);
 759 }
 760
 761 static void write_config(struct string_list *config)
 762 {
 763         int i;
 764
 765         for (i = 0; i < config->nr; i++) {
 766                 if (git_config_parse_parameter(config->items[i].string,
 767                                                write_one_config, NULL) < 0)
 768                         die(_("unable to write parameters to config file"));
 769         }
 770 }
 771
 772 static void write_refspec_config(const char *src_ref_prefix,
 773                 const struct ref *our_head_points_at,
 774                 const struct ref *remote_head_points_at,
 775                 struct strbuf *branch_top)
 776 {
 777         struct strbuf key = STRBUF_INIT;
 778         struct strbuf value = STRBUF_INIT;
 779
 780         if (option_mirror || !option_bare) {
 781                 if (option_single_branch && !option_mirror) {
 782                         if (option_branch) {
 783                                 if (starts_with(our_head_points_at->name, "refs/tags/"))
 784                                         strbuf_addf(&value, "+%s:%s", our_head_points_at->name,
 785                                                 our_head_points_at->name);
 786                                 else
 787                                         strbuf_addf(&value, "+%s:%s%s", our_head_points_at->name,
 788                                                 branch_top->buf, option_branch);
 789                         } else if (remote_head_points_at) {
 790                                 const char *head = remote_head_points_at->name;
 791                                 if (!skip_prefix(head, "refs/heads/", &head))
 792                                         die("BUG: remote HEAD points at non-head?");
 793
 794                                 strbuf_addf(&value, "+%s:%s%s", remote_head_points_at->name,
 795                                                 branch_top->buf, head);
 796                         }
 797                         /*
 798                          * otherwise, the next "git fetch" will
 799                          * simply fetch from HEAD without updating
 800                          * any remote-tracking branch, which is what
 801                          * we want.
 802                          */
 803                 } else {
 804                         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top->buf);
 805                 }
 806                 /* Configure the remote */
 807                 if (value.len) {
 808                         strbuf_addf(&key, "remote.%s.fetch", option_origin);
 809                         git_config_set_multivar(key.buf, value.buf, "^$", 0);
 810                         strbuf_reset(&key);
 811
 812                         if (option_mirror) {
 813                                 strbuf_addf(&key, "remote.%s.mirror", option_origin);
 814                                 git_config_set(key.buf, "true");
 815                                 strbuf_reset(&key);
 816                         }
 817                 }
 818         }
 819
 820         strbuf_release(&key);
 821         strbuf_release(&value);
 822 }
 823
 824 static void dissociate_from_references(void)
 825 {
 826         static const char* argv[] = { "repack", "-a", "-d", NULL };
 827         char *alternates = git_pathdup("objects/info/alternates");
 828
 829         if (!access(alternates, F_OK)) {
 830                 if (run_command_v_opt(argv, RUN_GIT_CMD|RUN_COMMAND_NO_STDIN))
 831                         die(_("cannot repack to clean up"));
 832                 if (unlink(alternates) && errno != ENOENT)
 833                         die_errno(_("cannot unlink temporary alternates file"));
 834         }
 835         free(alternates);
 836 }
 837
 838 int cmd_clone(int argc, const char **argv, const char *prefix)
 839 {
 840         int is_bundle = 0, is_local;
 841         struct stat buf;
 842         const char *repo_name, *repo, *work_tree, *git_dir;
 843         char *path, *dir;
 844         int dest_exists;
 845         const struct ref *refs, *remote_head;
 846         const struct ref *remote_head_points_at;
 847         const struct ref *our_head_points_at;
 848         struct ref *mapped_refs;
 849         const struct ref *ref;
 850         struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
 851         struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
 852         struct transport *transport = NULL;
 853         const char *src_ref_prefix = "refs/heads/";
 854         struct remote *remote;
 855         int err = 0, complete_refs_before_fetch = 1;
 856         int submodule_progress;
 857
 858         struct refspec *refspec;
 859         const char *fetch_pattern;
 860
 861         packet_trace_identity("clone");
 862         argc = parse_options(argc, argv, prefix, builtin_clone_options,
 863                              builtin_clone_usage, 0);
 864
 865         if (argc > 2)
 866                 usage_msg_opt(_("Too many arguments."),
 867                         builtin_clone_usage, builtin_clone_options);
 868
 869         if (argc == 0)
 870                 usage_msg_opt(_("You must specify a repository to clone."),
 871                         builtin_clone_usage, builtin_clone_options);
 872
 873         if (option_depth || option_since || option_not.nr)
 874                 deepen = 1;
 875         if (option_single_branch == -1)
 876                 option_single_branch = deepen ? 1 : 0;
 877
 878         if (option_mirror)
 879                 option_bare = 1;
 880
 881         if (option_bare) {
 882                 if (option_origin)
 883                         die(_("--bare and --origin %s options are incompatible."),
 884                             option_origin);
 885                 if (real_git_dir)
 886                         die(_("--bare and --separate-git-dir are incompatible."));
 887                 option_no_checkout = 1;
 888         }
 889
 890         if (!option_origin)
 891                 option_origin = "origin";
 892
 893         repo_name = argv[0];
 894
 895         path = get_repo_path(repo_name, &is_bundle);
 896         if (path)
 897                 repo = absolute_pathdup(repo_name);
 898         else if (!strchr(repo_name, ':'))
 899                 die(_("repository '%s' does not exist"), repo_name);
 900         else
 901                 repo = repo_name;
 902
 903         /* no need to be strict, transport_set_option() will validate it again */
 904         if (option_depth && atoi(option_depth) < 1)
 905                 die(_("depth %s is not a positive number"), option_depth);
 906
 907         if (argc == 2)
 908                 dir = xstrdup(argv[1]);
 909         else
 910                 dir = guess_dir_name(repo_name, is_bundle, option_bare);
 911         strip_trailing_slashes(dir);
 912
 913         dest_exists = !stat(dir, &buf);
 914         if (dest_exists && !is_empty_dir(dir))
 915                 die(_("destination path '%s' already exists and is not "
 916                         "an empty directory."), dir);
 917
 918         strbuf_addf(&reflog_msg, "clone: from %s", repo);
 919
 920         if (option_bare)
 921                 work_tree = NULL;
 922         else {
 923                 work_tree = getenv("GIT_WORK_TREE");
 924                 if (work_tree && !stat(work_tree, &buf))
 925                         die(_("working tree '%s' already exists."), work_tree);
 926         }
 927
 928         if (option_bare || work_tree)
 929                 git_dir = xstrdup(dir);
 930         else {
 931                 work_tree = dir;
 932                 git_dir = mkpathdup("%s/.git", dir);
 933         }
 934
 935         atexit(remove_junk);
 936         sigchain_push_common(remove_junk_on_signal);
 937
 938         if (!option_bare) {
 939                 if (safe_create_leading_directories_const(work_tree) < 0)
 940                         die_errno(_("could not create leading directories of '%s'"),
 941                                   work_tree);
 942                 if (!dest_exists && mkdir(work_tree, 0777))
 943                         die_errno(_("could not create work tree dir '%s'"),
 944                                   work_tree);
 945                 junk_work_tree = work_tree;
 946                 set_git_work_tree(work_tree);
 947         }
 948
 949         junk_git_dir = real_git_dir ? real_git_dir : git_dir;
 950         if (safe_create_leading_directories_const(git_dir) < 0)
 951                 die(_("could not create leading directories of '%s'"), git_dir);
 952
 953         if (0 <= option_verbosity) {
 954                 if (option_bare)
 955                         fprintf(stderr, _("Cloning into bare repository '%s'...\n"), dir);
 956                 else
 957                         fprintf(stderr, _("Cloning into '%s'...\n"), dir);
 958         }
 959
 960         if (option_recursive) {
 961                 if (option_required_reference.nr &&
 962                     option_optional_reference.nr)
 963                         die(_("clone --recursive is not compatible with "
 964                               "both --reference and --reference-if-able"));
 965                 else if (option_required_reference.nr) {
 966                         string_list_append(&option_config,
 967                                 "submodule.alternateLocation=superproject");
 968                         string_list_append(&option_config,
 969                                 "submodule.alternateErrorStrategy=die");
 970                 } else if (option_optional_reference.nr) {
 971                         string_list_append(&option_config,
 972                                 "submodule.alternateLocation=superproject");
 973                         string_list_append(&option_config,
 974                                 "submodule.alternateErrorStrategy=info");
 975                 }
 976         }
 977
 978         init_db(git_dir, real_git_dir, option_template, INIT_DB_QUIET);
 979
 980         if (real_git_dir)
 981                 git_dir = real_git_dir;
 982
 983         write_config(&option_config);
 984
 985         git_config(git_default_config, NULL);
 986
 987         if (option_bare) {
 988                 if (option_mirror)
 989                         src_ref_prefix = "refs/";
 990                 strbuf_addstr(&branch_top, src_ref_prefix);
 991
 992                 git_config_set("core.bare", "true");
 993         } else {
 994                 strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
 995         }
 996
 997         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top.buf);
 998         strbuf_addf(&key, "remote.%s.url", option_origin);
 999         git_config_set(key.buf, repo);
1000         strbuf_reset(&key);
1001
1002         if (option_required_reference.nr || option_optional_reference.nr)
1003                 setup_reference();
1004
1005         fetch_pattern = value.buf;
1006         refspec = parse_fetch_refspec(1, &fetch_pattern);
1007
1008         strbuf_reset(&value);
1009
1010         remote = remote_get(option_origin);
1011         transport = transport_get(remote, remote->url[0]);
1012         transport_set_verbosity(transport, option_verbosity, option_progress);
1013         transport->family = family;
1014
1015         path = get_repo_path(remote->url[0], &is_bundle);
1016         is_local = option_local != 0 && path && !is_bundle;
1017         if (is_local) {
1018                 if (option_depth)
1019                         warning(_("--depth is ignored in local clones; use file:// instead."));
1020                 if (option_since)
1021                         warning(_("--shallow-since is ignored in local clones; use file:// instead."));
1022                 if (option_not.nr)
1023                         warning(_("--shallow-exclude is ignored in local clones; use file:// instead."));
1024                 if (!access(mkpath("%s/shallow", path), F_OK)) {
1025                         if (option_local > 0)
1026                                 warning(_("source repository is shallow, ignoring --local"));
1027                         is_local = 0;
1028                 }
1029         }
1030         if (option_local > 0 && !is_local)
1031                 warning(_("--local is ignored"));
1032         transport->cloning = 1;
1033
1034         if (!transport->get_refs_list || (!is_local && !transport->fetch))
1035                 die(_("Don't know how to clone %s"), transport->url);
1036
1037         transport_set_option(transport, TRANS_OPT_KEEP, "yes");
1038
1039         if (option_depth)
1040                 transport_set_option(transport, TRANS_OPT_DEPTH,
1041                                      option_depth);
1042         if (option_since)
1043                 transport_set_option(transport, TRANS_OPT_DEEPEN_SINCE,
1044                                      option_since);
1045         if (option_not.nr)
1046                 transport_set_option(transport, TRANS_OPT_DEEPEN_NOT,
1047                                      (const char *)&option_not);
1048         if (option_single_branch)
1049                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
1050
1051         if (option_upload_pack)
1052                 transport_set_option(transport, TRANS_OPT_UPLOADPACK,
1053                                      option_upload_pack);
1054
1055         if (transport->smart_options && !deepen)
1056                 transport->smart_options->check_self_contained_and_connected = 1;
1057
1058         refs = transport_get_remote_refs(transport);
1059
1060         if (refs) {
1061                 mapped_refs = wanted_peer_refs(refs, refspec);
1062                 /*
1063                  * transport_get_remote_refs() may return refs with null sha-1
1064                  * in mapped_refs (see struct transport->get_refs_list
1065                  * comment). In that case we need fetch it early because
1066                  * remote_head code below relies on it.
1067                  *
1068                  * for normal clones, transport_get_remote_refs() should
1069                  * return reliable ref set, we can delay cloning until after
1070                  * remote HEAD check.
1071                  */
1072                 for (ref = refs; ref; ref = ref->next)
1073                         if (is_null_oid(&ref->old_oid)) {
1074                                 complete_refs_before_fetch = 0;
1075                                 break;
1076                         }
1077
1078                 if (!is_local && !complete_refs_before_fetch)
1079                         transport_fetch_refs(transport, mapped_refs);
1080
1081                 remote_head = find_ref_by_name(refs, "HEAD");
1082                 remote_head_points_at =
1083                         guess_remote_head(remote_head, mapped_refs, 0);
1084
1085                 if (option_branch) {
1086                         our_head_points_at =
1087                                 find_remote_branch(mapped_refs, option_branch);
1088
1089                         if (!our_head_points_at)
1090                                 die(_("Remote branch %s not found in upstream %s"),
1091                                     option_branch, option_origin);
1092                 }
1093                 else
1094                         our_head_points_at = remote_head_points_at;
1095         }
1096         else {
1097                 if (option_branch)
1098                         die(_("Remote branch %s not found in upstream %s"),
1099                                         option_branch, option_origin);
1100
1101                 warning(_("You appear to have cloned an empty repository."));
1102                 mapped_refs = NULL;
1103                 our_head_points_at = NULL;
1104                 remote_head_points_at = NULL;
1105                 remote_head = NULL;
1106                 option_no_checkout = 1;
1107                 if (!option_bare)
1108                         install_branch_config(0, "master", option_origin,
1109                                               "refs/heads/master");
1110         }
1111
1112         write_refspec_config(src_ref_prefix, our_head_points_at,
1113                         remote_head_points_at, &branch_top);
1114
1115         if (is_local)
1116                 clone_local(path, git_dir);
1117         else if (refs && complete_refs_before_fetch)
1118                 transport_fetch_refs(transport, mapped_refs);
1119
1120         update_remote_refs(refs, mapped_refs, remote_head_points_at,
1121                            branch_top.buf, reflog_msg.buf, transport, !is_local);
1122
1123         update_head(our_head_points_at, remote_head, reflog_msg.buf);
1124
1125         /*
1126          * We want to show progress for recursive submodule clones iff
1127          * we did so for the main clone. But only the transport knows
1128          * the final decision for this flag, so we need to rescue the value
1129          * before we free the transport.
1130          */
1131         submodule_progress = transport->progress;
1132
1133         transport_unlock_pack(transport);
1134         transport_disconnect(transport);
1135
1136         if (option_dissociate) {
1137                 close_all_packs();
1138                 dissociate_from_references();
1139         }
1140
1141         junk_mode = JUNK_LEAVE_REPO;
1142         err = checkout(submodule_progress);
1143
1144         strbuf_release(&reflog_msg);
1145         strbuf_release(&branch_top);
1146         strbuf_release(&key);
1147         strbuf_release(&value);
1148         junk_mode = JUNK_LEAVE_ALL;
1149
1150         free(refspec);
1151         return err;
1152 }