builtin/fetch.c

   1 /*
   2  * "git fetch"
   3  */
   4 #include "cache.h"
   5 #include "refs.h"
   6 #include "commit.h"
   7 #include "builtin.h"
   8 #include "string-list.h"
   9 #include "remote.h"
  10 #include "transport.h"
  11 #include "run-command.h"
  12 #include "parse-options.h"
  13 #include "sigchain.h"
  14 #include "transport.h"
  15 #include "submodule.h"
  16
  17 static const char * const builtin_fetch_usage[] = {
  18         "git fetch [<options>] [<repository> [<refspec>...]]",
  19         "git fetch [<options>] <group>",
  20         "git fetch --multiple [<options>] [(<repository> | <group>)...]",
  21         "git fetch --all [<options>]",
  22         NULL
  23 };
  24
  25 enum {
  26         TAGS_UNSET = 0,
  27         TAGS_DEFAULT = 1,
  28         TAGS_SET = 2
  29 };
  30
  31 static int all, append, dry_run, force, keep, multiple, prune, update_head_ok, verbosity;
  32 static int progress, recurse_submodules = RECURSE_SUBMODULES_DEFAULT;
  33 static int tags = TAGS_DEFAULT;
  34 static const char *depth;
  35 static const char *upload_pack;
  36 static struct strbuf default_rla = STRBUF_INIT;
  37 static struct transport *transport;
  38 static const char *submodule_prefix = "";
  39 static const char *recurse_submodules_default;
  40
  41 static int option_parse_recurse_submodules(const struct option *opt,
  42                                    const char *arg, int unset)
  43 {
  44         if (unset) {
  45                 recurse_submodules = RECURSE_SUBMODULES_OFF;
  46         } else {
  47                 if (arg)
  48                         recurse_submodules = parse_fetch_recurse_submodules_arg(opt->long_name, arg);
  49                 else
  50                         recurse_submodules = RECURSE_SUBMODULES_ON;
  51         }
  52         return 0;
  53 }
  54
  55 static struct option builtin_fetch_options[] = {
  56         OPT__VERBOSITY(&verbosity),
  57         OPT_BOOLEAN(0, "all", &all,
  58                     "fetch from all remotes"),
  59         OPT_BOOLEAN('a', "append", &append,
  60                     "append to .git/FETCH_HEAD instead of overwriting"),
  61         OPT_STRING(0, "upload-pack", &upload_pack, "path",
  62                    "path to upload pack on remote end"),
  63         OPT__FORCE(&force, "force overwrite of local branch"),
  64         OPT_BOOLEAN('m', "multiple", &multiple,
  65                     "fetch from multiple remotes"),
  66         OPT_SET_INT('t', "tags", &tags,
  67                     "fetch all tags and associated objects", TAGS_SET),
  68         OPT_SET_INT('n', NULL, &tags,
  69                     "do not fetch all tags (--no-tags)", TAGS_UNSET),
  70         OPT_BOOLEAN('p', "prune", &prune,
  71                     "prune remote-tracking branches no longer on remote"),
  72         { OPTION_CALLBACK, 0, "recurse-submodules", NULL, "on-demand",
  73                     "control recursive fetching of submodules",
  74                     PARSE_OPT_OPTARG, option_parse_recurse_submodules },
  75         OPT_BOOLEAN(0, "dry-run", &dry_run,
  76                     "dry run"),
  77         OPT_BOOLEAN('k', "keep", &keep, "keep downloaded pack"),
  78         OPT_BOOLEAN('u', "update-head-ok", &update_head_ok,
  79                     "allow updating of HEAD ref"),
  80         OPT_BOOLEAN(0, "progress", &progress, "force progress reporting"),
  81         OPT_STRING(0, "depth", &depth, "depth",
  82                    "deepen history of shallow clone"),
  83         { OPTION_STRING, 0, "submodule-prefix", &submodule_prefix, "dir",
  84                    "prepend this to submodule path output", PARSE_OPT_HIDDEN },
  85         { OPTION_STRING, 0, "recurse-submodules-default",
  86                    &recurse_submodules_default, NULL,
  87                    "default mode for recursion", PARSE_OPT_HIDDEN },
  88         OPT_END()
  89 };
  90
  91 static void unlock_pack(void)
  92 {
  93         if (transport)
  94                 transport_unlock_pack(transport);
  95 }
  96
  97 static void unlock_pack_on_signal(int signo)
  98 {
  99         unlock_pack();
 100         sigchain_pop(signo);
 101         raise(signo);
 102 }
 103
 104 static void add_merge_config(struct ref **head,
 105                            const struct ref *remote_refs,
 106                            struct branch *branch,
 107                            struct ref ***tail)
 108 {
 109         int i;
 110
 111         for (i = 0; i < branch->merge_nr; i++) {
 112                 struct ref *rm, **old_tail = *tail;
 113                 struct refspec refspec;
 114
 115                 for (rm = *head; rm; rm = rm->next) {
 116                         if (branch_merge_matches(branch, i, rm->name)) {
 117                                 rm->merge = 1;
 118                                 break;
 119                         }
 120                 }
 121                 if (rm)
 122                         continue;
 123
 124                 /*
 125                  * Not fetched to a remote-tracking branch?  We need to fetch
 126                  * it anyway to allow this branch's "branch.$name.merge"
 127                  * to be honored by 'git pull', but we do not have to
 128                  * fail if branch.$name.merge is misconfigured to point
 129                  * at a nonexisting branch.  If we were indeed called by
 130                  * 'git pull', it will notice the misconfiguration because
 131                  * there is no entry in the resulting FETCH_HEAD marked
 132                  * for merging.
 133                  */
 134                 memset(&refspec, 0, sizeof(refspec));
 135                 refspec.src = branch->merge[i]->src;
 136                 get_fetch_map(remote_refs, &refspec, tail, 1);
 137                 for (rm = *old_tail; rm; rm = rm->next)
 138                         rm->merge = 1;
 139         }
 140 }
 141
 142 static void find_non_local_tags(struct transport *transport,
 143                         struct ref **head,
 144                         struct ref ***tail);
 145
 146 static struct ref *get_ref_map(struct transport *transport,
 147                                struct refspec *refs, int ref_count, int tags,
 148                                int *autotags)
 149 {
 150         int i;
 151         struct ref *rm;
 152         struct ref *ref_map = NULL;
 153         struct ref **tail = &ref_map;
 154
 155         const struct ref *remote_refs = transport_get_remote_refs(transport);
 156
 157         if (ref_count || tags == TAGS_SET) {
 158                 for (i = 0; i < ref_count; i++) {
 159                         get_fetch_map(remote_refs, &refs[i], &tail, 0);
 160                         if (refs[i].dst && refs[i].dst[0])
 161                                 *autotags = 1;
 162                 }
 163                 /* Merge everything on the command line, but not --tags */
 164                 for (rm = ref_map; rm; rm = rm->next)
 165                         rm->merge = 1;
 166                 if (tags == TAGS_SET)
 167                         get_fetch_map(remote_refs, tag_refspec, &tail, 0);
 168         } else {
 169                 /* Use the defaults */
 170                 struct remote *remote = transport->remote;
 171                 struct branch *branch = branch_get(NULL);
 172                 int has_merge = branch_has_merge_config(branch);
 173                 if (remote &&
 174                     (remote->fetch_refspec_nr ||
 175                      /* Note: has_merge implies non-NULL branch->remote_name */
 176                      (has_merge && !strcmp(branch->remote_name, remote->name)))) {
 177                         for (i = 0; i < remote->fetch_refspec_nr; i++) {
 178                                 get_fetch_map(remote_refs, &remote->fetch[i], &tail, 0);
 179                                 if (remote->fetch[i].dst &&
 180                                     remote->fetch[i].dst[0])
 181                                         *autotags = 1;
 182                                 if (!i && !has_merge && ref_map &&
 183                                     !remote->fetch[0].pattern)
 184                                         ref_map->merge = 1;
 185                         }
 186                         /*
 187                          * if the remote we're fetching from is the same
 188                          * as given in branch.<name>.remote, we add the
 189                          * ref given in branch.<name>.merge, too.
 190                          *
 191                          * Note: has_merge implies non-NULL branch->remote_name
 192                          */
 193                         if (has_merge &&
 194                             !strcmp(branch->remote_name, remote->name))
 195                                 add_merge_config(&ref_map, remote_refs, branch, &tail);
 196                 } else {
 197                         ref_map = get_remote_ref(remote_refs, "HEAD");
 198                         if (!ref_map)
 199                                 die(_("Couldn't find remote ref HEAD"));
 200                         ref_map->merge = 1;
 201                         tail = &ref_map->next;
 202                 }
 203         }
 204         if (tags == TAGS_DEFAULT && *autotags)
 205                 find_non_local_tags(transport, &ref_map, &tail);
 206         ref_remove_duplicates(ref_map);
 207
 208         return ref_map;
 209 }
 210
 211 #define STORE_REF_ERROR_OTHER 1
 212 #define STORE_REF_ERROR_DF_CONFLICT 2
 213
 214 static int s_update_ref(const char *action,
 215                         struct ref *ref,
 216                         int check_old)
 217 {
 218         char msg[1024];
 219         char *rla = getenv("GIT_REFLOG_ACTION");
 220         static struct ref_lock *lock;
 221
 222         if (dry_run)
 223                 return 0;
 224         if (!rla)
 225                 rla = default_rla.buf;
 226         snprintf(msg, sizeof(msg), "%s: %s", rla, action);
 227         lock = lock_any_ref_for_update(ref->name,
 228                                        check_old ? ref->old_sha1 : NULL, 0);
 229         if (!lock)
 230                 return errno == ENOTDIR ? STORE_REF_ERROR_DF_CONFLICT :
 231                                           STORE_REF_ERROR_OTHER;
 232         if (write_ref_sha1(lock, ref->new_sha1, msg) < 0)
 233                 return errno == ENOTDIR ? STORE_REF_ERROR_DF_CONFLICT :
 234                                           STORE_REF_ERROR_OTHER;
 235         return 0;
 236 }
 237
 238 #define REFCOL_WIDTH  10
 239
 240 static int update_local_ref(struct ref *ref,
 241                             const char *remote,
 242                             char *display)
 243 {
 244         struct commit *current = NULL, *updated;
 245         enum object_type type;
 246         struct branch *current_branch = branch_get(NULL);
 247         const char *pretty_ref = prettify_refname(ref->name);
 248
 249         *display = 0;
 250         type = sha1_object_info(ref->new_sha1, NULL);
 251         if (type < 0)
 252                 die(_("object %s not found"), sha1_to_hex(ref->new_sha1));
 253
 254         if (!hashcmp(ref->old_sha1, ref->new_sha1)) {
 255                 if (verbosity > 0)
 256                         sprintf(display, "= %-*s %-*s -> %s", TRANSPORT_SUMMARY_WIDTH,
 257                                 _("[up to date]"), REFCOL_WIDTH, remote,
 258                                 pretty_ref);
 259                 return 0;
 260         }
 261
 262         if (current_branch &&
 263             !strcmp(ref->name, current_branch->name) &&
 264             !(update_head_ok || is_bare_repository()) &&
 265             !is_null_sha1(ref->old_sha1)) {
 266                 /*
 267                  * If this is the head, and it's not okay to update
 268                  * the head, and the old value of the head isn't empty...
 269                  */
 270                 sprintf(display, _("! %-*s %-*s -> %s  (can't fetch in current branch)"),
 271                         TRANSPORT_SUMMARY_WIDTH, _("[rejected]"), REFCOL_WIDTH, remote,
 272                         pretty_ref);
 273                 return 1;
 274         }
 275
 276         if (!is_null_sha1(ref->old_sha1) &&
 277             !prefixcmp(ref->name, "refs/tags/")) {
 278                 int r;
 279                 r = s_update_ref("updating tag", ref, 0);
 280                 sprintf(display, "%c %-*s %-*s -> %s%s", r ? '!' : '-',
 281                         TRANSPORT_SUMMARY_WIDTH, _("[tag update]"), REFCOL_WIDTH, remote,
 282                         pretty_ref, r ? _("  (unable to update local ref)") : "");
 283                 return r;
 284         }
 285
 286         current = lookup_commit_reference_gently(ref->old_sha1, 1);
 287         updated = lookup_commit_reference_gently(ref->new_sha1, 1);
 288         if (!current || !updated) {
 289                 const char *msg;
 290                 const char *what;
 291                 int r;
 292                 if (!strncmp(ref->name, "refs/tags/", 10)) {
 293                         msg = "storing tag";
 294                         what = _("[new tag]");
 295                 }
 296                 else {
 297                         msg = "storing head";
 298                         what = _("[new branch]");
 299                         if ((recurse_submodules != RECURSE_SUBMODULES_OFF) &&
 300                             (recurse_submodules != RECURSE_SUBMODULES_ON))
 301                                 check_for_new_submodule_commits(ref->new_sha1);
 302                 }
 303
 304                 r = s_update_ref(msg, ref, 0);
 305                 sprintf(display, "%c %-*s %-*s -> %s%s", r ? '!' : '*',
 306                         TRANSPORT_SUMMARY_WIDTH, what, REFCOL_WIDTH, remote, pretty_ref,
 307                         r ? _("  (unable to update local ref)") : "");
 308                 return r;
 309         }
 310
 311         if (in_merge_bases(current, &updated, 1)) {
 312                 char quickref[83];
 313                 int r;
 314                 strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
 315                 strcat(quickref, "..");
 316                 strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
 317                 if ((recurse_submodules != RECURSE_SUBMODULES_OFF) &&
 318                     (recurse_submodules != RECURSE_SUBMODULES_ON))
 319                         check_for_new_submodule_commits(ref->new_sha1);
 320                 r = s_update_ref("fast-forward", ref, 1);
 321                 sprintf(display, "%c %-*s %-*s -> %s%s", r ? '!' : ' ',
 322                         TRANSPORT_SUMMARY_WIDTH, quickref, REFCOL_WIDTH, remote,
 323                         pretty_ref, r ? _("  (unable to update local ref)") : "");
 324                 return r;
 325         } else if (force || ref->force) {
 326                 char quickref[84];
 327                 int r;
 328                 strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
 329                 strcat(quickref, "...");
 330                 strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
 331                 if ((recurse_submodules != RECURSE_SUBMODULES_OFF) &&
 332                     (recurse_submodules != RECURSE_SUBMODULES_ON))
 333                         check_for_new_submodule_commits(ref->new_sha1);
 334                 r = s_update_ref("forced-update", ref, 1);
 335                 sprintf(display, "%c %-*s %-*s -> %s  (%s)", r ? '!' : '+',
 336                         TRANSPORT_SUMMARY_WIDTH, quickref, REFCOL_WIDTH, remote,
 337                         pretty_ref,
 338                         r ? _("unable to update local ref") : _("forced update"));
 339                 return r;
 340         } else {
 341                 sprintf(display, "! %-*s %-*s -> %s  %s",
 342                         TRANSPORT_SUMMARY_WIDTH, _("[rejected]"), REFCOL_WIDTH, remote,
 343                         pretty_ref, _("(non-fast-forward)"));
 344                 return 1;
 345         }
 346 }
 347
 348 /*
 349  * The ref_map records the tips of the refs we are fetching. If
 350  *
 351  *  $ git rev-list --verify-objects --stdin --not --all
 352  *
 353  * (feeding all the refs in ref_map on its standard input) does not
 354  * error out, that means everything reachable from these updated refs
 355  * locally exists and is connected to some of our existing refs.
 356  *
 357  * Returns 0 if everything is connected, non-zero otherwise.
 358  */
 359 static int check_everything_connected(struct ref *ref_map, int quiet)
 360 {
 361         struct child_process rev_list;
 362         const char *argv[] = {"rev-list", "--verify-objects",
 363                               "--stdin", "--not", "--all", NULL, NULL};
 364         char commit[41];
 365         struct ref *ref;
 366         int err = 0;
 367
 368         if (!ref_map)
 369                 return 0;
 370
 371         if (quiet)
 372                 argv[5] = "--quiet";
 373
 374         memset(&rev_list, 0, sizeof(rev_list));
 375         rev_list.argv = argv;
 376         rev_list.git_cmd = 1;
 377         rev_list.in = -1;
 378         rev_list.no_stdout = 1;
 379         rev_list.no_stderr = quiet;
 380         if (start_command(&rev_list))
 381                 return error(_("Could not run 'git rev-list'"));
 382
 383         sigchain_push(SIGPIPE, SIG_IGN);
 384
 385         memcpy(commit + 40, "\n", 2);
 386         for (ref = ref_map; ref; ref = ref->next) {
 387                 memcpy(commit, sha1_to_hex(ref->old_sha1), 40);
 388                 if (write_in_full(rev_list.in, commit, 41) < 0) {
 389                         if (errno != EPIPE && errno != EINVAL)
 390                                 error(_("failed write to rev-list: %s"),
 391                                       strerror(errno));
 392                         err = -1;
 393                         break;
 394                 }
 395         }
 396         if (close(rev_list.in)) {
 397                 error(_("failed to close rev-list's stdin: %s"), strerror(errno));
 398                 err = -1;
 399         }
 400
 401         sigchain_pop(SIGPIPE);
 402
 403         return finish_command(&rev_list) || err;
 404 }
 405
 406 static int store_updated_refs(const char *raw_url, const char *remote_name,
 407                 struct ref *ref_map)
 408 {
 409         FILE *fp;
 410         struct commit *commit;
 411         int url_len, i, note_len, shown_url = 0, rc = 0;
 412         char note[1024];
 413         const char *what, *kind;
 414         struct ref *rm;
 415         char *url, *filename = dry_run ? "/dev/null" : git_path("FETCH_HEAD");
 416
 417         fp = fopen(filename, "a");
 418         if (!fp)
 419                 return error(_("cannot open %s: %s\n"), filename, strerror(errno));
 420
 421         if (raw_url)
 422                 url = transport_anonymize_url(raw_url);
 423         else
 424                 url = xstrdup("foreign");
 425
 426         if (check_everything_connected(ref_map, 0))
 427                 return error(_("%s did not send all necessary objects\n"), url);
 428
 429         for (rm = ref_map; rm; rm = rm->next) {
 430                 struct ref *ref = NULL;
 431
 432                 if (rm->peer_ref) {
 433                         ref = xcalloc(1, sizeof(*ref) + strlen(rm->peer_ref->name) + 1);
 434                         strcpy(ref->name, rm->peer_ref->name);
 435                         hashcpy(ref->old_sha1, rm->peer_ref->old_sha1);
 436                         hashcpy(ref->new_sha1, rm->old_sha1);
 437                         ref->force = rm->peer_ref->force;
 438                 }
 439
 440                 commit = lookup_commit_reference_gently(rm->old_sha1, 1);
 441                 if (!commit)
 442                         rm->merge = 0;
 443
 444                 if (!strcmp(rm->name, "HEAD")) {
 445                         kind = "";
 446                         what = "";
 447                 }
 448                 else if (!prefixcmp(rm->name, "refs/heads/")) {
 449                         kind = "branch";
 450                         what = rm->name + 11;
 451                 }
 452                 else if (!prefixcmp(rm->name, "refs/tags/")) {
 453                         kind = "tag";
 454                         what = rm->name + 10;
 455                 }
 456                 else if (!prefixcmp(rm->name, "refs/remotes/")) {
 457                         kind = "remote-tracking branch";
 458                         what = rm->name + 13;
 459                 }
 460                 else {
 461                         kind = "";
 462                         what = rm->name;
 463                 }
 464
 465                 url_len = strlen(url);
 466                 for (i = url_len - 1; url[i] == '/' && 0 <= i; i--)
 467                         ;
 468                 url_len = i + 1;
 469                 if (4 < i && !strncmp(".git", url + i - 3, 4))
 470                         url_len = i - 3;
 471
 472                 note_len = 0;
 473                 if (*what) {
 474                         if (*kind)
 475                                 note_len += sprintf(note + note_len, "%s ",
 476                                                     kind);
 477                         note_len += sprintf(note + note_len, "'%s' of ", what);
 478                 }
 479                 note[note_len] = '\0';
 480                 fprintf(fp, "%s\t%s\t%s",
 481                         sha1_to_hex(commit ? commit->object.sha1 :
 482                                     rm->old_sha1),
 483                         rm->merge ? "" : "not-for-merge",
 484                         note);
 485                 for (i = 0; i < url_len; ++i)
 486                         if ('\n' == url[i])
 487                                 fputs("\\n", fp);
 488                         else
 489                                 fputc(url[i], fp);
 490                 fputc('\n', fp);
 491
 492                 if (ref) {
 493                         rc |= update_local_ref(ref, what, note);
 494                         free(ref);
 495                 } else
 496                         sprintf(note, "* %-*s %-*s -> FETCH_HEAD",
 497                                 TRANSPORT_SUMMARY_WIDTH, *kind ? kind : "branch",
 498                                  REFCOL_WIDTH, *what ? what : "HEAD");
 499                 if (*note) {
 500                         if (verbosity >= 0 && !shown_url) {
 501                                 fprintf(stderr, _("From %.*s\n"),
 502                                                 url_len, url);
 503                                 shown_url = 1;
 504                         }
 505                         if (verbosity >= 0)
 506                                 fprintf(stderr, " %s\n", note);
 507                 }
 508         }
 509         free(url);
 510         fclose(fp);
 511         if (rc & STORE_REF_ERROR_DF_CONFLICT)
 512                 error(_("some local refs could not be updated; try running\n"
 513                       " 'git remote prune %s' to remove any old, conflicting "
 514                       "branches"), remote_name);
 515         return rc;
 516 }
 517
 518 /*
 519  * We would want to bypass the object transfer altogether if
 520  * everything we are going to fetch already exists and is connected
 521  * locally.
 522  */
 523 static int quickfetch(struct ref *ref_map)
 524 {
 525         /*
 526          * If we are deepening a shallow clone we already have these
 527          * objects reachable.  Running rev-list here will return with
 528          * a good (0) exit status and we'll bypass the fetch that we
 529          * really need to perform.  Claiming failure now will ensure
 530          * we perform the network exchange to deepen our history.
 531          */
 532         if (depth)
 533                 return -1;
 534         return check_everything_connected(ref_map, 1);
 535 }
 536
 537 static int fetch_refs(struct transport *transport, struct ref *ref_map)
 538 {
 539         int ret = quickfetch(ref_map);
 540         if (ret)
 541                 ret = transport_fetch_refs(transport, ref_map);
 542         if (!ret)
 543                 ret |= store_updated_refs(transport->url,
 544                                 transport->remote->name,
 545                                 ref_map);
 546         transport_unlock_pack(transport);
 547         return ret;
 548 }
 549
 550 static int prune_refs(struct transport *transport, struct ref *ref_map)
 551 {
 552         int result = 0;
 553         struct ref *ref, *stale_refs = get_stale_heads(transport->remote, ref_map);
 554         const char *dangling_msg = dry_run
 555                 ? _("   (%s will become dangling)\n")
 556                 : _("   (%s has become dangling)\n");
 557
 558         for (ref = stale_refs; ref; ref = ref->next) {
 559                 if (!dry_run)
 560                         result |= delete_ref(ref->name, NULL, 0);
 561                 if (verbosity >= 0) {
 562                         fprintf(stderr, " x %-*s %-*s -> %s\n",
 563                                 TRANSPORT_SUMMARY_WIDTH, _("[deleted]"),
 564                                 REFCOL_WIDTH, _("(none)"), prettify_refname(ref->name));
 565                         warn_dangling_symref(stderr, dangling_msg, ref->name);
 566                 }
 567         }
 568         free_refs(stale_refs);
 569         return result;
 570 }
 571
 572 static int add_existing(const char *refname, const unsigned char *sha1,
 573                         int flag, void *cbdata)
 574 {
 575         struct string_list *list = (struct string_list *)cbdata;
 576         struct string_list_item *item = string_list_insert(list, refname);
 577         item->util = (void *)sha1;
 578         return 0;
 579 }
 580
 581 static int will_fetch(struct ref **head, const unsigned char *sha1)
 582 {
 583         struct ref *rm = *head;
 584         while (rm) {
 585                 if (!hashcmp(rm->old_sha1, sha1))
 586                         return 1;
 587                 rm = rm->next;
 588         }
 589         return 0;
 590 }
 591
 592 static void find_non_local_tags(struct transport *transport,
 593                         struct ref **head,
 594                         struct ref ***tail)
 595 {
 596         struct string_list existing_refs = STRING_LIST_INIT_NODUP;
 597         struct string_list remote_refs = STRING_LIST_INIT_NODUP;
 598         const struct ref *ref;
 599         struct string_list_item *item = NULL;
 600
 601         for_each_ref(add_existing, &existing_refs);
 602         for (ref = transport_get_remote_refs(transport); ref; ref = ref->next) {
 603                 if (prefixcmp(ref->name, "refs/tags"))
 604                         continue;
 605
 606                 /*
 607                  * The peeled ref always follows the matching base
 608                  * ref, so if we see a peeled ref that we don't want
 609                  * to fetch then we can mark the ref entry in the list
 610                  * as one to ignore by setting util to NULL.
 611                  */
 612                 if (!suffixcmp(ref->name, "^{}")) {
 613                         if (item && !has_sha1_file(ref->old_sha1) &&
 614                             !will_fetch(head, ref->old_sha1) &&
 615                             !has_sha1_file(item->util) &&
 616                             !will_fetch(head, item->util))
 617                                 item->util = NULL;
 618                         item = NULL;
 619                         continue;
 620                 }
 621
 622                 /*
 623                  * If item is non-NULL here, then we previously saw a
 624                  * ref not followed by a peeled reference, so we need
 625                  * to check if it is a lightweight tag that we want to
 626                  * fetch.
 627                  */
 628                 if (item && !has_sha1_file(item->util) &&
 629                     !will_fetch(head, item->util))
 630                         item->util = NULL;
 631
 632                 item = NULL;
 633
 634                 /* skip duplicates and refs that we already have */
 635                 if (string_list_has_string(&remote_refs, ref->name) ||
 636                     string_list_has_string(&existing_refs, ref->name))
 637                         continue;
 638
 639                 item = string_list_insert(&remote_refs, ref->name);
 640                 item->util = (void *)ref->old_sha1;
 641         }
 642         string_list_clear(&existing_refs, 0);
 643
 644         /*
 645          * We may have a final lightweight tag that needs to be
 646          * checked to see if it needs fetching.
 647          */
 648         if (item && !has_sha1_file(item->util) &&
 649             !will_fetch(head, item->util))
 650                 item->util = NULL;
 651
 652         /*
 653          * For all the tags in the remote_refs string list,
 654          * add them to the list of refs to be fetched
 655          */
 656         for_each_string_list_item(item, &remote_refs) {
 657                 /* Unless we have already decided to ignore this item... */
 658                 if (item->util)
 659                 {
 660                         struct ref *rm = alloc_ref(item->string);
 661                         rm->peer_ref = alloc_ref(item->string);
 662                         hashcpy(rm->old_sha1, item->util);
 663                         **tail = rm;
 664                         *tail = &rm->next;
 665                 }
 666         }
 667
 668         string_list_clear(&remote_refs, 0);
 669 }
 670
 671 static void check_not_current_branch(struct ref *ref_map)
 672 {
 673         struct branch *current_branch = branch_get(NULL);
 674
 675         if (is_bare_repository() || !current_branch)
 676                 return;
 677
 678         for (; ref_map; ref_map = ref_map->next)
 679                 if (ref_map->peer_ref && !strcmp(current_branch->refname,
 680                                         ref_map->peer_ref->name))
 681                         die(_("Refusing to fetch into current branch %s "
 682                             "of non-bare repository"), current_branch->refname);
 683 }
 684
 685 static int truncate_fetch_head(void)
 686 {
 687         char *filename = git_path("FETCH_HEAD");
 688         FILE *fp = fopen(filename, "w");
 689
 690         if (!fp)
 691                 return error(_("cannot open %s: %s\n"), filename, strerror(errno));
 692         fclose(fp);
 693         return 0;
 694 }
 695
 696 static int do_fetch(struct transport *transport,
 697                     struct refspec *refs, int ref_count)
 698 {
 699         struct string_list existing_refs = STRING_LIST_INIT_NODUP;
 700         struct string_list_item *peer_item = NULL;
 701         struct ref *ref_map;
 702         struct ref *rm;
 703         int autotags = (transport->remote->fetch_tags == 1);
 704
 705         for_each_ref(add_existing, &existing_refs);
 706
 707         if (tags == TAGS_DEFAULT) {
 708                 if (transport->remote->fetch_tags == 2)
 709                         tags = TAGS_SET;
 710                 if (transport->remote->fetch_tags == -1)
 711                         tags = TAGS_UNSET;
 712         }
 713
 714         if (!transport->get_refs_list || !transport->fetch)
 715                 die(_("Don't know how to fetch from %s"), transport->url);
 716
 717         /* if not appending, truncate FETCH_HEAD */
 718         if (!append && !dry_run) {
 719                 int errcode = truncate_fetch_head();
 720                 if (errcode)
 721                         return errcode;
 722         }
 723
 724         ref_map = get_ref_map(transport, refs, ref_count, tags, &autotags);
 725         if (!update_head_ok)
 726                 check_not_current_branch(ref_map);
 727
 728         for (rm = ref_map; rm; rm = rm->next) {
 729                 if (rm->peer_ref) {
 730                         peer_item = string_list_lookup(&existing_refs,
 731                                                        rm->peer_ref->name);
 732                         if (peer_item)
 733                                 hashcpy(rm->peer_ref->old_sha1,
 734                                         peer_item->util);
 735                 }
 736         }
 737
 738         if (tags == TAGS_DEFAULT && autotags)
 739                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
 740         if (fetch_refs(transport, ref_map)) {
 741                 free_refs(ref_map);
 742                 return 1;
 743         }
 744         if (prune)
 745                 prune_refs(transport, ref_map);
 746         free_refs(ref_map);
 747
 748         /* if neither --no-tags nor --tags was specified, do automated tag
 749          * following ... */
 750         if (tags == TAGS_DEFAULT && autotags) {
 751                 struct ref **tail = &ref_map;
 752                 ref_map = NULL;
 753                 find_non_local_tags(transport, &ref_map, &tail);
 754                 if (ref_map) {
 755                         transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, NULL);
 756                         transport_set_option(transport, TRANS_OPT_DEPTH, "0");
 757                         fetch_refs(transport, ref_map);
 758                 }
 759                 free_refs(ref_map);
 760         }
 761
 762         return 0;
 763 }
 764
 765 static void set_option(const char *name, const char *value)
 766 {
 767         int r = transport_set_option(transport, name, value);
 768         if (r < 0)
 769                 die(_("Option \"%s\" value \"%s\" is not valid for %s"),
 770                         name, value, transport->url);
 771         if (r > 0)
 772                 warning(_("Option \"%s\" is ignored for %s\n"),
 773                         name, transport->url);
 774 }
 775
 776 static int get_one_remote_for_fetch(struct remote *remote, void *priv)
 777 {
 778         struct string_list *list = priv;
 779         if (!remote->skip_default_update)
 780                 string_list_append(list, remote->name);
 781         return 0;
 782 }
 783
 784 struct remote_group_data {
 785         const char *name;
 786         struct string_list *list;
 787 };
 788
 789 static int get_remote_group(const char *key, const char *value, void *priv)
 790 {
 791         struct remote_group_data *g = priv;
 792
 793         if (!prefixcmp(key, "remotes.") &&
 794                         !strcmp(key + 8, g->name)) {
 795                 /* split list by white space */
 796                 int space = strcspn(value, " \t\n");
 797                 while (*value) {
 798                         if (space > 1) {
 799                                 string_list_append(g->list,
 800                                                    xstrndup(value, space));
 801                         }
 802                         value += space + (value[space] != '\0');
 803                         space = strcspn(value, " \t\n");
 804                 }
 805         }
 806
 807         return 0;
 808 }
 809
 810 static int add_remote_or_group(const char *name, struct string_list *list)
 811 {
 812         int prev_nr = list->nr;
 813         struct remote_group_data g;
 814         g.name = name; g.list = list;
 815
 816         git_config(get_remote_group, &g);
 817         if (list->nr == prev_nr) {
 818                 struct remote *remote;
 819                 if (!remote_is_configured(name))
 820                         return 0;
 821                 remote = remote_get(name);
 822                 string_list_append(list, remote->name);
 823         }
 824         return 1;
 825 }
 826
 827 static void add_options_to_argv(int *argc, const char **argv)
 828 {
 829         if (dry_run)
 830                 argv[(*argc)++] = "--dry-run";
 831         if (prune)
 832                 argv[(*argc)++] = "--prune";
 833         if (update_head_ok)
 834                 argv[(*argc)++] = "--update-head-ok";
 835         if (force)
 836                 argv[(*argc)++] = "--force";
 837         if (keep)
 838                 argv[(*argc)++] = "--keep";
 839         if (recurse_submodules == RECURSE_SUBMODULES_ON)
 840                 argv[(*argc)++] = "--recurse-submodules";
 841         else if (recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND)
 842                 argv[(*argc)++] = "--recurse-submodules=on-demand";
 843         if (verbosity >= 2)
 844                 argv[(*argc)++] = "-v";
 845         if (verbosity >= 1)
 846                 argv[(*argc)++] = "-v";
 847         else if (verbosity < 0)
 848                 argv[(*argc)++] = "-q";
 849
 850 }
 851
 852 static int fetch_multiple(struct string_list *list)
 853 {
 854         int i, result = 0;
 855         const char *argv[12] = { "fetch", "--append" };
 856         int argc = 2;
 857
 858         add_options_to_argv(&argc, argv);
 859
 860         if (!append && !dry_run) {
 861                 int errcode = truncate_fetch_head();
 862                 if (errcode)
 863                         return errcode;
 864         }
 865
 866         for (i = 0; i < list->nr; i++) {
 867                 const char *name = list->items[i].string;
 868                 argv[argc] = name;
 869                 argv[argc + 1] = NULL;
 870                 if (verbosity >= 0)
 871                         printf(_("Fetching %s\n"), name);
 872                 if (run_command_v_opt(argv, RUN_GIT_CMD)) {
 873                         error(_("Could not fetch %s"), name);
 874                         result = 1;
 875                 }
 876         }
 877
 878         return result;
 879 }
 880
 881 static int fetch_one(struct remote *remote, int argc, const char **argv)
 882 {
 883         int i;
 884         static const char **refs = NULL;
 885         struct refspec *refspec;
 886         int ref_nr = 0;
 887         int exit_code;
 888
 889         if (!remote)
 890                 die(_("No remote repository specified.  Please, specify either a URL or a\n"
 891                     "remote name from which new revisions should be fetched."));
 892
 893         transport = transport_get(remote, NULL);
 894         transport_set_verbosity(transport, verbosity, progress);
 895         if (upload_pack)
 896                 set_option(TRANS_OPT_UPLOADPACK, upload_pack);
 897         if (keep)
 898                 set_option(TRANS_OPT_KEEP, "yes");
 899         if (depth)
 900                 set_option(TRANS_OPT_DEPTH, depth);
 901
 902         if (argc > 0) {
 903                 int j = 0;
 904                 refs = xcalloc(argc + 1, sizeof(const char *));
 905                 for (i = 0; i < argc; i++) {
 906                         if (!strcmp(argv[i], "tag")) {
 907                                 char *ref;
 908                                 i++;
 909                                 if (i >= argc)
 910                                         die(_("You need to specify a tag name."));
 911                                 ref = xmalloc(strlen(argv[i]) * 2 + 22);
 912                                 strcpy(ref, "refs/tags/");
 913                                 strcat(ref, argv[i]);
 914                                 strcat(ref, ":refs/tags/");
 915                                 strcat(ref, argv[i]);
 916                                 refs[j++] = ref;
 917                         } else
 918                                 refs[j++] = argv[i];
 919                 }
 920                 refs[j] = NULL;
 921                 ref_nr = j;
 922         }
 923
 924         sigchain_push_common(unlock_pack_on_signal);
 925         atexit(unlock_pack);
 926         refspec = parse_fetch_refspec(ref_nr, refs);
 927         exit_code = do_fetch(transport, refspec, ref_nr);
 928         free(refspec);
 929         transport_disconnect(transport);
 930         transport = NULL;
 931         return exit_code;
 932 }
 933
 934 int cmd_fetch(int argc, const char **argv, const char *prefix)
 935 {
 936         int i;
 937         struct string_list list = STRING_LIST_INIT_NODUP;
 938         struct remote *remote;
 939         int result = 0;
 940
 941         packet_trace_identity("fetch");
 942
 943         /* Record the command line for the reflog */
 944         strbuf_addstr(&default_rla, "fetch");
 945         for (i = 1; i < argc; i++)
 946                 strbuf_addf(&default_rla, " %s", argv[i]);
 947
 948         argc = parse_options(argc, argv, prefix,
 949                              builtin_fetch_options, builtin_fetch_usage, 0);
 950
 951         if (recurse_submodules != RECURSE_SUBMODULES_OFF) {
 952                 if (recurse_submodules_default) {
 953                         int arg = parse_fetch_recurse_submodules_arg("--recurse-submodules-default", recurse_submodules_default);
 954                         set_config_fetch_recurse_submodules(arg);
 955                 }
 956                 gitmodules_config();
 957                 git_config(submodule_config, NULL);
 958         }
 959
 960         if (all) {
 961                 if (argc == 1)
 962                         die(_("fetch --all does not take a repository argument"));
 963                 else if (argc > 1)
 964                         die(_("fetch --all does not make sense with refspecs"));
 965                 (void) for_each_remote(get_one_remote_for_fetch, &list);
 966                 result = fetch_multiple(&list);
 967         } else if (argc == 0) {
 968                 /* No arguments -- use default remote */
 969                 remote = remote_get(NULL);
 970                 result = fetch_one(remote, argc, argv);
 971         } else if (multiple) {
 972                 /* All arguments are assumed to be remotes or groups */
 973                 for (i = 0; i < argc; i++)
 974                         if (!add_remote_or_group(argv[i], &list))
 975                                 die(_("No such remote or remote group: %s"), argv[i]);
 976                 result = fetch_multiple(&list);
 977         } else {
 978                 /* Single remote or group */
 979                 (void) add_remote_or_group(argv[0], &list);
 980                 if (list.nr > 1) {
 981                         /* More than one remote */
 982                         if (argc > 1)
 983                                 die(_("Fetching a group and specifying refspecs does not make sense"));
 984                         result = fetch_multiple(&list);
 985                 } else {
 986                         /* Zero or one remotes */
 987                         remote = remote_get(argv[0]);
 988                         result = fetch_one(remote, argc-1, argv+1);
 989                 }
 990         }
 991
 992         if (!result && (recurse_submodules != RECURSE_SUBMODULES_OFF)) {
 993                 const char *options[10];
 994                 int num_options = 0;
 995                 add_options_to_argv(&num_options, options);
 996                 result = fetch_populated_submodules(num_options, options,
 997                                                     submodule_prefix,
 998                                                     recurse_submodules,
 999                                                     verbosity < 0);
1000         }
1001
1002         /* All names were strdup()ed or strndup()ed */
1003         list.strdup_strings = 1;
1004         string_list_clear(&list, 0);
1005
1006         return result;
1007 }