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 #include "connected.h"
  17 #include "argv-array.h"
  18
  19 static const char * const builtin_fetch_usage[] = {
  20         N_("git fetch [<options>] [<repository> [<refspec>...]]"),
  21         N_("git fetch [<options>] <group>"),
  22         N_("git fetch --multiple [<options>] [(<repository> | <group>)...]"),
  23         N_("git fetch --all [<options>]"),
  24         NULL
  25 };
  26
  27 enum {
  28         TAGS_UNSET = 0,
  29         TAGS_DEFAULT = 1,
  30         TAGS_SET = 2
  31 };
  32
  33 static int all, append, dry_run, force, keep, multiple, prune, update_head_ok, verbosity;
  34 static int progress = -1, recurse_submodules = RECURSE_SUBMODULES_DEFAULT;
  35 static int tags = TAGS_DEFAULT, unshallow;
  36 static const char *depth;
  37 static const char *upload_pack;
  38 static struct strbuf default_rla = STRBUF_INIT;
  39 static struct transport *transport;
  40 static const char *submodule_prefix = "";
  41 static const char *recurse_submodules_default;
  42
  43 static int option_parse_recurse_submodules(const struct option *opt,
  44                                    const char *arg, int unset)
  45 {
  46         if (unset) {
  47                 recurse_submodules = RECURSE_SUBMODULES_OFF;
  48         } else {
  49                 if (arg)
  50                         recurse_submodules = parse_fetch_recurse_submodules_arg(opt->long_name, arg);
  51                 else
  52                         recurse_submodules = RECURSE_SUBMODULES_ON;
  53         }
  54         return 0;
  55 }
  56
  57 static struct option builtin_fetch_options[] = {
  58         OPT__VERBOSITY(&verbosity),
  59         OPT_BOOLEAN(0, "all", &all,
  60                     N_("fetch from all remotes")),
  61         OPT_BOOLEAN('a', "append", &append,
  62                     N_("append to .git/FETCH_HEAD instead of overwriting")),
  63         OPT_STRING(0, "upload-pack", &upload_pack, N_("path"),
  64                    N_("path to upload pack on remote end")),
  65         OPT__FORCE(&force, N_("force overwrite of local branch")),
  66         OPT_BOOLEAN('m', "multiple", &multiple,
  67                     N_("fetch from multiple remotes")),
  68         OPT_SET_INT('t', "tags", &tags,
  69                     N_("fetch all tags and associated objects"), TAGS_SET),
  70         OPT_SET_INT('n', NULL, &tags,
  71                     N_("do not fetch all tags (--no-tags)"), TAGS_UNSET),
  72         OPT_BOOLEAN('p', "prune", &prune,
  73                     N_("prune remote-tracking branches no longer on remote")),
  74         { OPTION_CALLBACK, 0, "recurse-submodules", NULL, N_("on-demand"),
  75                     N_("control recursive fetching of submodules"),
  76                     PARSE_OPT_OPTARG, option_parse_recurse_submodules },
  77         OPT_BOOLEAN(0, "dry-run", &dry_run,
  78                     N_("dry run")),
  79         OPT_BOOLEAN('k', "keep", &keep, N_("keep downloaded pack")),
  80         OPT_BOOLEAN('u', "update-head-ok", &update_head_ok,
  81                     N_("allow updating of HEAD ref")),
  82         OPT_BOOL(0, "progress", &progress, N_("force progress reporting")),
  83         OPT_STRING(0, "depth", &depth, N_("depth"),
  84                    N_("deepen history of shallow clone")),
  85         { OPTION_SET_INT, 0, "unshallow", &unshallow, NULL,
  86                    N_("convert to a complete repository"),
  87                    PARSE_OPT_NONEG | PARSE_OPT_NOARG, NULL, 1 },
  88         { OPTION_STRING, 0, "submodule-prefix", &submodule_prefix, N_("dir"),
  89                    N_("prepend this to submodule path output"), PARSE_OPT_HIDDEN },
  90         { OPTION_STRING, 0, "recurse-submodules-default",
  91                    &recurse_submodules_default, NULL,
  92                    N_("default mode for recursion"), PARSE_OPT_HIDDEN },
  93         OPT_END()
  94 };
  95
  96 static void unlock_pack(void)
  97 {
  98         if (transport)
  99                 transport_unlock_pack(transport);
 100 }
 101
 102 static void unlock_pack_on_signal(int signo)
 103 {
 104         unlock_pack();
 105         sigchain_pop(signo);
 106         raise(signo);
 107 }
 108
 109 static void add_merge_config(struct ref **head,
 110                            const struct ref *remote_refs,
 111                            struct branch *branch,
 112                            struct ref ***tail)
 113 {
 114         int i;
 115
 116         for (i = 0; i < branch->merge_nr; i++) {
 117                 struct ref *rm, **old_tail = *tail;
 118                 struct refspec refspec;
 119
 120                 for (rm = *head; rm; rm = rm->next) {
 121                         if (branch_merge_matches(branch, i, rm->name)) {
 122                                 rm->merge = 1;
 123                                 break;
 124                         }
 125                 }
 126                 if (rm)
 127                         continue;
 128
 129                 /*
 130                  * Not fetched to a remote-tracking branch?  We need to fetch
 131                  * it anyway to allow this branch's "branch.$name.merge"
 132                  * to be honored by 'git pull', but we do not have to
 133                  * fail if branch.$name.merge is misconfigured to point
 134                  * at a nonexisting branch.  If we were indeed called by
 135                  * 'git pull', it will notice the misconfiguration because
 136                  * there is no entry in the resulting FETCH_HEAD marked
 137                  * for merging.
 138                  */
 139                 memset(&refspec, 0, sizeof(refspec));
 140                 refspec.src = branch->merge[i]->src;
 141                 get_fetch_map(remote_refs, &refspec, tail, 1);
 142                 for (rm = *old_tail; rm; rm = rm->next)
 143                         rm->merge = 1;
 144         }
 145 }
 146
 147 static void find_non_local_tags(struct transport *transport,
 148                         struct ref **head,
 149                         struct ref ***tail);
 150
 151 static struct ref *get_ref_map(struct transport *transport,
 152                                struct refspec *refs, int ref_count, int tags,
 153                                int *autotags)
 154 {
 155         int i;
 156         struct ref *rm;
 157         struct ref *ref_map = NULL;
 158         struct ref **tail = &ref_map;
 159
 160         const struct ref *remote_refs = transport_get_remote_refs(transport);
 161
 162         if (ref_count || tags == TAGS_SET) {
 163                 for (i = 0; i < ref_count; i++) {
 164                         get_fetch_map(remote_refs, &refs[i], &tail, 0);
 165                         if (refs[i].dst && refs[i].dst[0])
 166                                 *autotags = 1;
 167                 }
 168                 /* Merge everything on the command line, but not --tags */
 169                 for (rm = ref_map; rm; rm = rm->next)
 170                         rm->merge = 1;
 171                 if (tags == TAGS_SET)
 172                         get_fetch_map(remote_refs, tag_refspec, &tail, 0);
 173         } else {
 174                 /* Use the defaults */
 175                 struct remote *remote = transport->remote;
 176                 struct branch *branch = branch_get(NULL);
 177                 int has_merge = branch_has_merge_config(branch);
 178                 if (remote &&
 179                     (remote->fetch_refspec_nr ||
 180                      /* Note: has_merge implies non-NULL branch->remote_name */
 181                      (has_merge && !strcmp(branch->remote_name, remote->name)))) {
 182                         for (i = 0; i < remote->fetch_refspec_nr; i++) {
 183                                 get_fetch_map(remote_refs, &remote->fetch[i], &tail, 0);
 184                                 if (remote->fetch[i].dst &&
 185                                     remote->fetch[i].dst[0])
 186                                         *autotags = 1;
 187                                 if (!i && !has_merge && ref_map &&
 188                                     !remote->fetch[0].pattern)
 189                                         ref_map->merge = 1;
 190                         }
 191                         /*
 192                          * if the remote we're fetching from is the same
 193                          * as given in branch.<name>.remote, we add the
 194                          * ref given in branch.<name>.merge, too.
 195                          *
 196                          * Note: has_merge implies non-NULL branch->remote_name
 197                          */
 198                         if (has_merge &&
 199                             !strcmp(branch->remote_name, remote->name))
 200                                 add_merge_config(&ref_map, remote_refs, branch, &tail);
 201                 } else {
 202                         ref_map = get_remote_ref(remote_refs, "HEAD");
 203                         if (!ref_map)
 204                                 die(_("Couldn't find remote ref HEAD"));
 205                         ref_map->merge = 1;
 206                         tail = &ref_map->next;
 207                 }
 208         }
 209         if (tags == TAGS_DEFAULT && *autotags)
 210                 find_non_local_tags(transport, &ref_map, &tail);
 211         ref_remove_duplicates(ref_map);
 212
 213         return ref_map;
 214 }
 215
 216 #define STORE_REF_ERROR_OTHER 1
 217 #define STORE_REF_ERROR_DF_CONFLICT 2
 218
 219 static int s_update_ref(const char *action,
 220                         struct ref *ref,
 221                         int check_old)
 222 {
 223         char msg[1024];
 224         char *rla = getenv("GIT_REFLOG_ACTION");
 225         static struct ref_lock *lock;
 226
 227         if (dry_run)
 228                 return 0;
 229         if (!rla)
 230                 rla = default_rla.buf;
 231         snprintf(msg, sizeof(msg), "%s: %s", rla, action);
 232         lock = lock_any_ref_for_update(ref->name,
 233                                        check_old ? ref->old_sha1 : NULL, 0);
 234         if (!lock)
 235                 return errno == ENOTDIR ? STORE_REF_ERROR_DF_CONFLICT :
 236                                           STORE_REF_ERROR_OTHER;
 237         if (write_ref_sha1(lock, ref->new_sha1, msg) < 0)
 238                 return errno == ENOTDIR ? STORE_REF_ERROR_DF_CONFLICT :
 239                                           STORE_REF_ERROR_OTHER;
 240         return 0;
 241 }
 242
 243 #define REFCOL_WIDTH  10
 244
 245 static int update_local_ref(struct ref *ref,
 246                             const char *remote,
 247                             const struct ref *remote_ref,
 248                             struct strbuf *display)
 249 {
 250         struct commit *current = NULL, *updated;
 251         enum object_type type;
 252         struct branch *current_branch = branch_get(NULL);
 253         const char *pretty_ref = prettify_refname(ref->name);
 254
 255         type = sha1_object_info(ref->new_sha1, NULL);
 256         if (type < 0)
 257                 die(_("object %s not found"), sha1_to_hex(ref->new_sha1));
 258
 259         if (!hashcmp(ref->old_sha1, ref->new_sha1)) {
 260                 if (verbosity > 0)
 261                         strbuf_addf(display, "= %-*s %-*s -> %s",
 262                                     TRANSPORT_SUMMARY(_("[up to date]")),
 263                                     REFCOL_WIDTH, remote, pretty_ref);
 264                 return 0;
 265         }
 266
 267         if (current_branch &&
 268             !strcmp(ref->name, current_branch->name) &&
 269             !(update_head_ok || is_bare_repository()) &&
 270             !is_null_sha1(ref->old_sha1)) {
 271                 /*
 272                  * If this is the head, and it's not okay to update
 273                  * the head, and the old value of the head isn't empty...
 274                  */
 275                 strbuf_addf(display,
 276                             _("! %-*s %-*s -> %s  (can't fetch in current branch)"),
 277                             TRANSPORT_SUMMARY(_("[rejected]")),
 278                             REFCOL_WIDTH, remote, pretty_ref);
 279                 return 1;
 280         }
 281
 282         if (!is_null_sha1(ref->old_sha1) &&
 283             !prefixcmp(ref->name, "refs/tags/")) {
 284                 int r;
 285                 r = s_update_ref("updating tag", ref, 0);
 286                 strbuf_addf(display, "%c %-*s %-*s -> %s%s",
 287                             r ? '!' : '-',
 288                             TRANSPORT_SUMMARY(_("[tag update]")),
 289                             REFCOL_WIDTH, remote, pretty_ref,
 290                             r ? _("  (unable to update local ref)") : "");
 291                 return r;
 292         }
 293
 294         current = lookup_commit_reference_gently(ref->old_sha1, 1);
 295         updated = lookup_commit_reference_gently(ref->new_sha1, 1);
 296         if (!current || !updated) {
 297                 const char *msg;
 298                 const char *what;
 299                 int r;
 300                 /*
 301                  * Nicely describe the new ref we're fetching.
 302                  * Base this on the remote's ref name, as it's
 303                  * more likely to follow a standard layout.
 304                  */
 305                 const char *name = remote_ref ? remote_ref->name : "";
 306                 if (!prefixcmp(name, "refs/tags/")) {
 307                         msg = "storing tag";
 308                         what = _("[new tag]");
 309                 } else if (!prefixcmp(name, "refs/heads/")) {
 310                         msg = "storing head";
 311                         what = _("[new branch]");
 312                 } else {
 313                         msg = "storing ref";
 314                         what = _("[new ref]");
 315                 }
 316
 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(msg, ref, 0);
 321                 strbuf_addf(display, "%c %-*s %-*s -> %s%s",
 322                             r ? '!' : '*',
 323                             TRANSPORT_SUMMARY(what),
 324                             REFCOL_WIDTH, remote, pretty_ref,
 325                             r ? _("  (unable to update local ref)") : "");
 326                 return r;
 327         }
 328
 329         if (in_merge_bases(current, updated)) {
 330                 char quickref[83];
 331                 int r;
 332                 strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
 333                 strcat(quickref, "..");
 334                 strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
 335                 if ((recurse_submodules != RECURSE_SUBMODULES_OFF) &&
 336                     (recurse_submodules != RECURSE_SUBMODULES_ON))
 337                         check_for_new_submodule_commits(ref->new_sha1);
 338                 r = s_update_ref("fast-forward", ref, 1);
 339                 strbuf_addf(display, "%c %-*s %-*s -> %s%s",
 340                             r ? '!' : ' ',
 341                             TRANSPORT_SUMMARY_WIDTH, quickref,
 342                             REFCOL_WIDTH, remote, pretty_ref,
 343                             r ? _("  (unable to update local ref)") : "");
 344                 return r;
 345         } else if (force || ref->force) {
 346                 char quickref[84];
 347                 int r;
 348                 strcpy(quickref, find_unique_abbrev(current->object.sha1, DEFAULT_ABBREV));
 349                 strcat(quickref, "...");
 350                 strcat(quickref, find_unique_abbrev(ref->new_sha1, DEFAULT_ABBREV));
 351                 if ((recurse_submodules != RECURSE_SUBMODULES_OFF) &&
 352                     (recurse_submodules != RECURSE_SUBMODULES_ON))
 353                         check_for_new_submodule_commits(ref->new_sha1);
 354                 r = s_update_ref("forced-update", ref, 1);
 355                 strbuf_addf(display, "%c %-*s %-*s -> %s  (%s)",
 356                             r ? '!' : '+',
 357                             TRANSPORT_SUMMARY_WIDTH, quickref,
 358                             REFCOL_WIDTH, remote, pretty_ref,
 359                             r ? _("unable to update local ref") : _("forced update"));
 360                 return r;
 361         } else {
 362                 strbuf_addf(display, "! %-*s %-*s -> %s  %s",
 363                             TRANSPORT_SUMMARY(_("[rejected]")),
 364                             REFCOL_WIDTH, remote, pretty_ref,
 365                             _("(non-fast-forward)"));
 366                 return 1;
 367         }
 368 }
 369
 370 static int iterate_ref_map(void *cb_data, unsigned char sha1[20])
 371 {
 372         struct ref **rm = cb_data;
 373         struct ref *ref = *rm;
 374
 375         if (!ref)
 376                 return -1; /* end of the list */
 377         *rm = ref->next;
 378         hashcpy(sha1, ref->old_sha1);
 379         return 0;
 380 }
 381
 382 static int store_updated_refs(const char *raw_url, const char *remote_name,
 383                 struct ref *ref_map)
 384 {
 385         FILE *fp;
 386         struct commit *commit;
 387         int url_len, i, shown_url = 0, rc = 0;
 388         struct strbuf note = STRBUF_INIT;
 389         const char *what, *kind;
 390         struct ref *rm;
 391         char *url, *filename = dry_run ? "/dev/null" : git_path("FETCH_HEAD");
 392         int want_merge;
 393
 394         fp = fopen(filename, "a");
 395         if (!fp)
 396                 return error(_("cannot open %s: %s\n"), filename, strerror(errno));
 397
 398         if (raw_url)
 399                 url = transport_anonymize_url(raw_url);
 400         else
 401                 url = xstrdup("foreign");
 402
 403         rm = ref_map;
 404         if (check_everything_connected(iterate_ref_map, 0, &rm)) {
 405                 rc = error(_("%s did not send all necessary objects\n"), url);
 406                 goto abort;
 407         }
 408
 409         /*
 410          * The first pass writes objects to be merged and then the
 411          * second pass writes the rest, in order to allow using
 412          * FETCH_HEAD as a refname to refer to the ref to be merged.
 413          */
 414         for (want_merge = 1; 0 <= want_merge; want_merge--) {
 415                 for (rm = ref_map; rm; rm = rm->next) {
 416                         struct ref *ref = NULL;
 417
 418                         commit = lookup_commit_reference_gently(rm->old_sha1, 1);
 419                         if (!commit)
 420                                 rm->merge = 0;
 421
 422                         if (rm->merge != want_merge)
 423                                 continue;
 424
 425                         if (rm->peer_ref) {
 426                                 ref = xcalloc(1, sizeof(*ref) + strlen(rm->peer_ref->name) + 1);
 427                                 strcpy(ref->name, rm->peer_ref->name);
 428                                 hashcpy(ref->old_sha1, rm->peer_ref->old_sha1);
 429                                 hashcpy(ref->new_sha1, rm->old_sha1);
 430                                 ref->force = rm->peer_ref->force;
 431                         }
 432
 433
 434                         if (!strcmp(rm->name, "HEAD")) {
 435                                 kind = "";
 436                                 what = "";
 437                         }
 438                         else if (!prefixcmp(rm->name, "refs/heads/")) {
 439                                 kind = "branch";
 440                                 what = rm->name + 11;
 441                         }
 442                         else if (!prefixcmp(rm->name, "refs/tags/")) {
 443                                 kind = "tag";
 444                                 what = rm->name + 10;
 445                         }
 446                         else if (!prefixcmp(rm->name, "refs/remotes/")) {
 447                                 kind = "remote-tracking branch";
 448                                 what = rm->name + 13;
 449                         }
 450                         else {
 451                                 kind = "";
 452                                 what = rm->name;
 453                         }
 454
 455                         url_len = strlen(url);
 456                         for (i = url_len - 1; url[i] == '/' && 0 <= i; i--)
 457                                 ;
 458                         url_len = i + 1;
 459                         if (4 < i && !strncmp(".git", url + i - 3, 4))
 460                                 url_len = i - 3;
 461
 462                         strbuf_reset(&note);
 463                         if (*what) {
 464                                 if (*kind)
 465                                         strbuf_addf(&note, "%s ", kind);
 466                                 strbuf_addf(&note, "'%s' of ", what);
 467                         }
 468                         fprintf(fp, "%s\t%s\t%s",
 469                                 sha1_to_hex(rm->old_sha1),
 470                                 rm->merge ? "" : "not-for-merge",
 471                                 note.buf);
 472                         for (i = 0; i < url_len; ++i)
 473                                 if ('\n' == url[i])
 474                                         fputs("\\n", fp);
 475                                 else
 476                                         fputc(url[i], fp);
 477                         fputc('\n', fp);
 478
 479                         strbuf_reset(&note);
 480                         if (ref) {
 481                                 rc |= update_local_ref(ref, what, rm, &note);
 482                                 free(ref);
 483                         } else
 484                                 strbuf_addf(&note, "* %-*s %-*s -> FETCH_HEAD",
 485                                             TRANSPORT_SUMMARY_WIDTH,
 486                                             *kind ? kind : "branch",
 487                                             REFCOL_WIDTH,
 488                                             *what ? what : "HEAD");
 489                         if (note.len) {
 490                                 if (verbosity >= 0 && !shown_url) {
 491                                         fprintf(stderr, _("From %.*s\n"),
 492                                                         url_len, url);
 493                                         shown_url = 1;
 494                                 }
 495                                 if (verbosity >= 0)
 496                                         fprintf(stderr, " %s\n", note.buf);
 497                         }
 498                 }
 499         }
 500
 501         if (rc & STORE_REF_ERROR_DF_CONFLICT)
 502                 error(_("some local refs could not be updated; try running\n"
 503                       " 'git remote prune %s' to remove any old, conflicting "
 504                       "branches"), remote_name);
 505
 506  abort:
 507         strbuf_release(&note);
 508         free(url);
 509         fclose(fp);
 510         return rc;
 511 }
 512
 513 /*
 514  * We would want to bypass the object transfer altogether if
 515  * everything we are going to fetch already exists and is connected
 516  * locally.
 517  */
 518 static int quickfetch(struct ref *ref_map)
 519 {
 520         struct ref *rm = ref_map;
 521
 522         /*
 523          * If we are deepening a shallow clone we already have these
 524          * objects reachable.  Running rev-list here will return with
 525          * a good (0) exit status and we'll bypass the fetch that we
 526          * really need to perform.  Claiming failure now will ensure
 527          * we perform the network exchange to deepen our history.
 528          */
 529         if (depth)
 530                 return -1;
 531         return check_everything_connected(iterate_ref_map, 1, &rm);
 532 }
 533
 534 static int fetch_refs(struct transport *transport, struct ref *ref_map)
 535 {
 536         int ret = quickfetch(ref_map);
 537         if (ret)
 538                 ret = transport_fetch_refs(transport, ref_map);
 539         if (!ret)
 540                 ret |= store_updated_refs(transport->url,
 541                                 transport->remote->name,
 542                                 ref_map);
 543         transport_unlock_pack(transport);
 544         return ret;
 545 }
 546
 547 static int prune_refs(struct refspec *refs, int ref_count, struct ref *ref_map)
 548 {
 549         int result = 0;
 550         struct ref *ref, *stale_refs = get_stale_heads(refs, ref_count, ref_map);
 551         const char *dangling_msg = dry_run
 552                 ? _("   (%s will become dangling)")
 553                 : _("   (%s has become dangling)");
 554
 555         for (ref = stale_refs; ref; ref = ref->next) {
 556                 if (!dry_run)
 557                         result |= delete_ref(ref->name, NULL, 0);
 558                 if (verbosity >= 0) {
 559                         fprintf(stderr, " x %-*s %-*s -> %s\n",
 560                                 TRANSPORT_SUMMARY(_("[deleted]")),
 561                                 REFCOL_WIDTH, _("(none)"), prettify_refname(ref->name));
 562                         warn_dangling_symref(stderr, dangling_msg, ref->name);
 563                 }
 564         }
 565         free_refs(stale_refs);
 566         return result;
 567 }
 568
 569 static int add_existing(const char *refname, const unsigned char *sha1,
 570                         int flag, void *cbdata)
 571 {
 572         struct string_list *list = (struct string_list *)cbdata;
 573         struct string_list_item *item = string_list_insert(list, refname);
 574         item->util = (void *)sha1;
 575         return 0;
 576 }
 577
 578 static int will_fetch(struct ref **head, const unsigned char *sha1)
 579 {
 580         struct ref *rm = *head;
 581         while (rm) {
 582                 if (!hashcmp(rm->old_sha1, sha1))
 583                         return 1;
 584                 rm = rm->next;
 585         }
 586         return 0;
 587 }
 588
 589 static void find_non_local_tags(struct transport *transport,
 590                         struct ref **head,
 591                         struct ref ***tail)
 592 {
 593         struct string_list existing_refs = STRING_LIST_INIT_DUP;
 594         struct string_list remote_refs = STRING_LIST_INIT_NODUP;
 595         const struct ref *ref;
 596         struct string_list_item *item = NULL;
 597
 598         for_each_ref(add_existing, &existing_refs);
 599         for (ref = transport_get_remote_refs(transport); ref; ref = ref->next) {
 600                 if (prefixcmp(ref->name, "refs/tags/"))
 601                         continue;
 602
 603                 /*
 604                  * The peeled ref always follows the matching base
 605                  * ref, so if we see a peeled ref that we don't want
 606                  * to fetch then we can mark the ref entry in the list
 607                  * as one to ignore by setting util to NULL.
 608                  */
 609                 if (!suffixcmp(ref->name, "^{}")) {
 610                         if (item && !has_sha1_file(ref->old_sha1) &&
 611                             !will_fetch(head, ref->old_sha1) &&
 612                             !has_sha1_file(item->util) &&
 613                             !will_fetch(head, item->util))
 614                                 item->util = NULL;
 615                         item = NULL;
 616                         continue;
 617                 }
 618
 619                 /*
 620                  * If item is non-NULL here, then we previously saw a
 621                  * ref not followed by a peeled reference, so we need
 622                  * to check if it is a lightweight tag that we want to
 623                  * fetch.
 624                  */
 625                 if (item && !has_sha1_file(item->util) &&
 626                     !will_fetch(head, item->util))
 627                         item->util = NULL;
 628
 629                 item = NULL;
 630
 631                 /* skip duplicates and refs that we already have */
 632                 if (string_list_has_string(&remote_refs, ref->name) ||
 633                     string_list_has_string(&existing_refs, ref->name))
 634                         continue;
 635
 636                 item = string_list_insert(&remote_refs, ref->name);
 637                 item->util = (void *)ref->old_sha1;
 638         }
 639         string_list_clear(&existing_refs, 0);
 640
 641         /*
 642          * We may have a final lightweight tag that needs to be
 643          * checked to see if it needs fetching.
 644          */
 645         if (item && !has_sha1_file(item->util) &&
 646             !will_fetch(head, item->util))
 647                 item->util = NULL;
 648
 649         /*
 650          * For all the tags in the remote_refs string list,
 651          * add them to the list of refs to be fetched
 652          */
 653         for_each_string_list_item(item, &remote_refs) {
 654                 /* Unless we have already decided to ignore this item... */
 655                 if (item->util)
 656                 {
 657                         struct ref *rm = alloc_ref(item->string);
 658                         rm->peer_ref = alloc_ref(item->string);
 659                         hashcpy(rm->old_sha1, item->util);
 660                         **tail = rm;
 661                         *tail = &rm->next;
 662                 }
 663         }
 664
 665         string_list_clear(&remote_refs, 0);
 666 }
 667
 668 static void check_not_current_branch(struct ref *ref_map)
 669 {
 670         struct branch *current_branch = branch_get(NULL);
 671
 672         if (is_bare_repository() || !current_branch)
 673                 return;
 674
 675         for (; ref_map; ref_map = ref_map->next)
 676                 if (ref_map->peer_ref && !strcmp(current_branch->refname,
 677                                         ref_map->peer_ref->name))
 678                         die(_("Refusing to fetch into current branch %s "
 679                             "of non-bare repository"), current_branch->refname);
 680 }
 681
 682 static int truncate_fetch_head(void)
 683 {
 684         char *filename = git_path("FETCH_HEAD");
 685         FILE *fp = fopen(filename, "w");
 686
 687         if (!fp)
 688                 return error(_("cannot open %s: %s\n"), filename, strerror(errno));
 689         fclose(fp);
 690         return 0;
 691 }
 692
 693 static int do_fetch(struct transport *transport,
 694                     struct refspec *refs, int ref_count)
 695 {
 696         struct string_list existing_refs = STRING_LIST_INIT_DUP;
 697         struct string_list_item *peer_item = NULL;
 698         struct ref *ref_map;
 699         struct ref *rm;
 700         int autotags = (transport->remote->fetch_tags == 1);
 701
 702         for_each_ref(add_existing, &existing_refs);
 703
 704         if (tags == TAGS_DEFAULT) {
 705                 if (transport->remote->fetch_tags == 2)
 706                         tags = TAGS_SET;
 707                 if (transport->remote->fetch_tags == -1)
 708                         tags = TAGS_UNSET;
 709         }
 710
 711         if (!transport->get_refs_list || !transport->fetch)
 712                 die(_("Don't know how to fetch from %s"), transport->url);
 713
 714         /* if not appending, truncate FETCH_HEAD */
 715         if (!append && !dry_run) {
 716                 int errcode = truncate_fetch_head();
 717                 if (errcode)
 718                         return errcode;
 719         }
 720
 721         ref_map = get_ref_map(transport, refs, ref_count, tags, &autotags);
 722         if (!update_head_ok)
 723                 check_not_current_branch(ref_map);
 724
 725         for (rm = ref_map; rm; rm = rm->next) {
 726                 if (rm->peer_ref) {
 727                         peer_item = string_list_lookup(&existing_refs,
 728                                                        rm->peer_ref->name);
 729                         if (peer_item)
 730                                 hashcpy(rm->peer_ref->old_sha1,
 731                                         peer_item->util);
 732                 }
 733         }
 734
 735         if (tags == TAGS_DEFAULT && autotags)
 736                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
 737         if (fetch_refs(transport, ref_map)) {
 738                 free_refs(ref_map);
 739                 return 1;
 740         }
 741         if (prune) {
 742                 /* If --tags was specified, pretend the user gave us the canonical tags refspec */
 743                 if (tags == TAGS_SET) {
 744                         const char *tags_str = "refs/tags/*:refs/tags/*";
 745                         struct refspec *tags_refspec, *refspec;
 746
 747                         /* Copy the refspec and add the tags to it */
 748                         refspec = xcalloc(ref_count + 1, sizeof(struct refspec));
 749                         tags_refspec = parse_fetch_refspec(1, &tags_str);
 750                         memcpy(refspec, refs, ref_count * sizeof(struct refspec));
 751                         memcpy(&refspec[ref_count], tags_refspec, sizeof(struct refspec));
 752                         ref_count++;
 753
 754                         prune_refs(refspec, ref_count, ref_map);
 755
 756                         ref_count--;
 757                         /* The rest of the strings belong to fetch_one */
 758                         free_refspec(1, tags_refspec);
 759                         free(refspec);
 760                 } else if (ref_count) {
 761                         prune_refs(refs, ref_count, ref_map);
 762                 } else {
 763                         prune_refs(transport->remote->fetch, transport->remote->fetch_refspec_nr, ref_map);
 764                 }
 765         }
 766         free_refs(ref_map);
 767
 768         /* if neither --no-tags nor --tags was specified, do automated tag
 769          * following ... */
 770         if (tags == TAGS_DEFAULT && autotags) {
 771                 struct ref **tail = &ref_map;
 772                 ref_map = NULL;
 773                 find_non_local_tags(transport, &ref_map, &tail);
 774                 if (ref_map) {
 775                         transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, NULL);
 776                         transport_set_option(transport, TRANS_OPT_DEPTH, "0");
 777                         fetch_refs(transport, ref_map);
 778                 }
 779                 free_refs(ref_map);
 780         }
 781
 782         return 0;
 783 }
 784
 785 static void set_option(const char *name, const char *value)
 786 {
 787         int r = transport_set_option(transport, name, value);
 788         if (r < 0)
 789                 die(_("Option \"%s\" value \"%s\" is not valid for %s"),
 790                         name, value, transport->url);
 791         if (r > 0)
 792                 warning(_("Option \"%s\" is ignored for %s\n"),
 793                         name, transport->url);
 794 }
 795
 796 static int get_one_remote_for_fetch(struct remote *remote, void *priv)
 797 {
 798         struct string_list *list = priv;
 799         if (!remote->skip_default_update)
 800                 string_list_append(list, remote->name);
 801         return 0;
 802 }
 803
 804 struct remote_group_data {
 805         const char *name;
 806         struct string_list *list;
 807 };
 808
 809 static int get_remote_group(const char *key, const char *value, void *priv)
 810 {
 811         struct remote_group_data *g = priv;
 812
 813         if (!prefixcmp(key, "remotes.") &&
 814                         !strcmp(key + 8, g->name)) {
 815                 /* split list by white space */
 816                 int space = strcspn(value, " \t\n");
 817                 while (*value) {
 818                         if (space > 1) {
 819                                 string_list_append(g->list,
 820                                                    xstrndup(value, space));
 821                         }
 822                         value += space + (value[space] != '\0');
 823                         space = strcspn(value, " \t\n");
 824                 }
 825         }
 826
 827         return 0;
 828 }
 829
 830 static int add_remote_or_group(const char *name, struct string_list *list)
 831 {
 832         int prev_nr = list->nr;
 833         struct remote_group_data g;
 834         g.name = name; g.list = list;
 835
 836         git_config(get_remote_group, &g);
 837         if (list->nr == prev_nr) {
 838                 struct remote *remote;
 839                 if (!remote_is_configured(name))
 840                         return 0;
 841                 remote = remote_get(name);
 842                 string_list_append(list, remote->name);
 843         }
 844         return 1;
 845 }
 846
 847 static void add_options_to_argv(struct argv_array *argv)
 848 {
 849         if (dry_run)
 850                 argv_array_push(argv, "--dry-run");
 851         if (prune)
 852                 argv_array_push(argv, "--prune");
 853         if (update_head_ok)
 854                 argv_array_push(argv, "--update-head-ok");
 855         if (force)
 856                 argv_array_push(argv, "--force");
 857         if (keep)
 858                 argv_array_push(argv, "--keep");
 859         if (recurse_submodules == RECURSE_SUBMODULES_ON)
 860                 argv_array_push(argv, "--recurse-submodules");
 861         else if (recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND)
 862                 argv_array_push(argv, "--recurse-submodules=on-demand");
 863         if (tags == TAGS_SET)
 864                 argv_array_push(argv, "--tags");
 865         else if (tags == TAGS_UNSET)
 866                 argv_array_push(argv, "--no-tags");
 867         if (verbosity >= 2)
 868                 argv_array_push(argv, "-v");
 869         if (verbosity >= 1)
 870                 argv_array_push(argv, "-v");
 871         else if (verbosity < 0)
 872                 argv_array_push(argv, "-q");
 873
 874 }
 875
 876 static int fetch_multiple(struct string_list *list)
 877 {
 878         int i, result = 0;
 879         struct argv_array argv = ARGV_ARRAY_INIT;
 880
 881         if (!append && !dry_run) {
 882                 int errcode = truncate_fetch_head();
 883                 if (errcode)
 884                         return errcode;
 885         }
 886
 887         argv_array_pushl(&argv, "fetch", "--append", NULL);
 888         add_options_to_argv(&argv);
 889
 890         for (i = 0; i < list->nr; i++) {
 891                 const char *name = list->items[i].string;
 892                 argv_array_push(&argv, name);
 893                 if (verbosity >= 0)
 894                         printf(_("Fetching %s\n"), name);
 895                 if (run_command_v_opt(argv.argv, RUN_GIT_CMD)) {
 896                         error(_("Could not fetch %s"), name);
 897                         result = 1;
 898                 }
 899                 argv_array_pop(&argv);
 900         }
 901
 902         argv_array_clear(&argv);
 903         return result;
 904 }
 905
 906 static int fetch_one(struct remote *remote, int argc, const char **argv)
 907 {
 908         int i;
 909         static const char **refs = NULL;
 910         struct refspec *refspec;
 911         int ref_nr = 0;
 912         int exit_code;
 913
 914         if (!remote)
 915                 die(_("No remote repository specified.  Please, specify either a URL or a\n"
 916                     "remote name from which new revisions should be fetched."));
 917
 918         transport = transport_get(remote, NULL);
 919         transport_set_verbosity(transport, verbosity, progress);
 920         if (upload_pack)
 921                 set_option(TRANS_OPT_UPLOADPACK, upload_pack);
 922         if (keep)
 923                 set_option(TRANS_OPT_KEEP, "yes");
 924         if (depth)
 925                 set_option(TRANS_OPT_DEPTH, depth);
 926
 927         if (argc > 0) {
 928                 int j = 0;
 929                 refs = xcalloc(argc + 1, sizeof(const char *));
 930                 for (i = 0; i < argc; i++) {
 931                         if (!strcmp(argv[i], "tag")) {
 932                                 char *ref;
 933                                 i++;
 934                                 if (i >= argc)
 935                                         die(_("You need to specify a tag name."));
 936                                 ref = xmalloc(strlen(argv[i]) * 2 + 22);
 937                                 strcpy(ref, "refs/tags/");
 938                                 strcat(ref, argv[i]);
 939                                 strcat(ref, ":refs/tags/");
 940                                 strcat(ref, argv[i]);
 941                                 refs[j++] = ref;
 942                         } else
 943                                 refs[j++] = argv[i];
 944                 }
 945                 refs[j] = NULL;
 946                 ref_nr = j;
 947         }
 948
 949         sigchain_push_common(unlock_pack_on_signal);
 950         atexit(unlock_pack);
 951         refspec = parse_fetch_refspec(ref_nr, refs);
 952         exit_code = do_fetch(transport, refspec, ref_nr);
 953         free_refspec(ref_nr, refspec);
 954         transport_disconnect(transport);
 955         transport = NULL;
 956         return exit_code;
 957 }
 958
 959 int cmd_fetch(int argc, const char **argv, const char *prefix)
 960 {
 961         int i;
 962         struct string_list list = STRING_LIST_INIT_NODUP;
 963         struct remote *remote;
 964         int result = 0;
 965         static const char *argv_gc_auto[] = {
 966                 "gc", "--auto", NULL,
 967         };
 968
 969         packet_trace_identity("fetch");
 970
 971         /* Record the command line for the reflog */
 972         strbuf_addstr(&default_rla, "fetch");
 973         for (i = 1; i < argc; i++)
 974                 strbuf_addf(&default_rla, " %s", argv[i]);
 975
 976         argc = parse_options(argc, argv, prefix,
 977                              builtin_fetch_options, builtin_fetch_usage, 0);
 978
 979         if (unshallow) {
 980                 if (depth)
 981                         die(_("--depth and --unshallow cannot be used together"));
 982                 else if (!is_repository_shallow())
 983                         die(_("--unshallow on a complete repository does not make sense"));
 984                 else {
 985                         static char inf_depth[12];
 986                         sprintf(inf_depth, "%d", INFINITE_DEPTH);
 987                         depth = inf_depth;
 988                 }
 989         }
 990
 991         if (recurse_submodules != RECURSE_SUBMODULES_OFF) {
 992                 if (recurse_submodules_default) {
 993                         int arg = parse_fetch_recurse_submodules_arg("--recurse-submodules-default", recurse_submodules_default);
 994                         set_config_fetch_recurse_submodules(arg);
 995                 }
 996                 gitmodules_config();
 997                 git_config(submodule_config, NULL);
 998         }
 999
1000         if (all) {
1001                 if (argc == 1)
1002                         die(_("fetch --all does not take a repository argument"));
1003                 else if (argc > 1)
1004                         die(_("fetch --all does not make sense with refspecs"));
1005                 (void) for_each_remote(get_one_remote_for_fetch, &list);
1006                 result = fetch_multiple(&list);
1007         } else if (argc == 0) {
1008                 /* No arguments -- use default remote */
1009                 remote = remote_get(NULL);
1010                 result = fetch_one(remote, argc, argv);
1011         } else if (multiple) {
1012                 /* All arguments are assumed to be remotes or groups */
1013                 for (i = 0; i < argc; i++)
1014                         if (!add_remote_or_group(argv[i], &list))
1015                                 die(_("No such remote or remote group: %s"), argv[i]);
1016                 result = fetch_multiple(&list);
1017         } else {
1018                 /* Single remote or group */
1019                 (void) add_remote_or_group(argv[0], &list);
1020                 if (list.nr > 1) {
1021                         /* More than one remote */
1022                         if (argc > 1)
1023                                 die(_("Fetching a group and specifying refspecs does not make sense"));
1024                         result = fetch_multiple(&list);
1025                 } else {
1026                         /* Zero or one remotes */
1027                         remote = remote_get(argv[0]);
1028                         result = fetch_one(remote, argc-1, argv+1);
1029                 }
1030         }
1031
1032         if (!result && (recurse_submodules != RECURSE_SUBMODULES_OFF)) {
1033                 struct argv_array options = ARGV_ARRAY_INIT;
1034
1035                 add_options_to_argv(&options);
1036                 result = fetch_populated_submodules(&options,
1037                                                     submodule_prefix,
1038                                                     recurse_submodules,
1039                                                     verbosity < 0);
1040                 argv_array_clear(&options);
1041         }
1042
1043         /* All names were strdup()ed or strndup()ed */
1044         list.strdup_strings = 1;
1045         string_list_clear(&list, 0);
1046
1047         run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
1048
1049         return result;
1050 }