git.oblomov.eu Git - git/blob - 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 static int store_updated_refs(const char *raw_url, const char *remote_name,
 349                 struct ref *ref_map)
 350 {
 351         FILE *fp;
 352         struct commit *commit;
 353         int url_len, i, note_len, shown_url = 0, rc = 0;
 354         char note[1024];
 355         const char *what, *kind;
 356         struct ref *rm;
 357         char *url, *filename = dry_run ? "/dev/null" : git_path("FETCH_HEAD");
 358
 359         fp = fopen(filename, "a");
 360         if (!fp)
 361                 return error(_("cannot open %s: %s\n"), filename, strerror(errno));
 362
 363         if (raw_url)
 364                 url = transport_anonymize_url(raw_url);
 365         else
 366                 url = xstrdup("foreign");
 367         for (rm = ref_map; rm; rm = rm->next) {
 368                 struct ref *ref = NULL;
 369
 370                 if (rm->peer_ref) {
 371                         ref = xcalloc(1, sizeof(*ref) + strlen(rm->peer_ref->name) + 1);
 372                         strcpy(ref->name, rm->peer_ref->name);
 373                         hashcpy(ref->old_sha1, rm->peer_ref->old_sha1);
 374                         hashcpy(ref->new_sha1, rm->old_sha1);
 375                         ref->force = rm->peer_ref->force;
 376                 }
 377
 378                 commit = lookup_commit_reference_gently(rm->old_sha1, 1);
 379                 if (!commit)
 380                         rm->merge = 0;
 381
 382                 if (!strcmp(rm->name, "HEAD")) {
 383                         kind = "";
 384                         what = "";
 385                 }
 386                 else if (!prefixcmp(rm->name, "refs/heads/")) {
 387                         kind = "branch";
 388                         what = rm->name + 11;
 389                 }
 390                 else if (!prefixcmp(rm->name, "refs/tags/")) {
 391                         kind = "tag";
 392                         what = rm->name + 10;
 393                 }
 394                 else if (!prefixcmp(rm->name, "refs/remotes/")) {
 395                         kind = "remote-tracking branch";
 396                         what = rm->name + 13;
 397                 }
 398                 else {
 399                         kind = "";
 400                         what = rm->name;
 401                 }
 402
 403                 url_len = strlen(url);
 404                 for (i = url_len - 1; url[i] == '/' && 0 <= i; i--)
 405                         ;
 406                 url_len = i + 1;
 407                 if (4 < i && !strncmp(".git", url + i - 3, 4))
 408                         url_len = i - 3;
 409
 410                 note_len = 0;
 411                 if (*what) {
 412                         if (*kind)
 413                                 note_len += sprintf(note + note_len, "%s ",
 414                                                     kind);
 415                         note_len += sprintf(note + note_len, "'%s' of ", what);
 416                 }
 417                 note[note_len] = '\0';
 418                 fprintf(fp, "%s\t%s\t%s",
 419                         sha1_to_hex(commit ? commit->object.sha1 :
 420                                     rm->old_sha1),
 421                         rm->merge ? "" : "not-for-merge",
 422                         note);
 423                 for (i = 0; i < url_len; ++i)
 424                         if ('\n' == url[i])
 425                                 fputs("\\n", fp);
 426                         else
 427                                 fputc(url[i], fp);
 428                 fputc('\n', fp);
 429
 430                 if (ref) {
 431                         rc |= update_local_ref(ref, what, note);
 432                         free(ref);
 433                 } else
 434                         sprintf(note, "* %-*s %-*s -> FETCH_HEAD",
 435                                 TRANSPORT_SUMMARY_WIDTH, *kind ? kind : "branch",
 436                                  REFCOL_WIDTH, *what ? what : "HEAD");
 437                 if (*note) {
 438                         if (verbosity >= 0 && !shown_url) {
 439                                 fprintf(stderr, _("From %.*s\n"),
 440                                                 url_len, url);
 441                                 shown_url = 1;
 442                         }
 443                         if (verbosity >= 0)
 444                                 fprintf(stderr, " %s\n", note);
 445                 }
 446         }
 447         free(url);
 448         fclose(fp);
 449         if (rc & STORE_REF_ERROR_DF_CONFLICT)
 450                 error(_("some local refs could not be updated; try running\n"
 451                       " 'git remote prune %s' to remove any old, conflicting "
 452                       "branches"), remote_name);
 453         return rc;
 454 }
 455
 456 /*
 457  * We would want to bypass the object transfer altogether if
 458  * everything we are going to fetch already exists and is connected
 459  * locally.
 460  *
 461  * The refs we are going to fetch are in ref_map.  If running
 462  *
 463  *  $ git rev-list --objects --stdin --not --all
 464  *
 465  * (feeding all the refs in ref_map on its standard input)
 466  * does not error out, that means everything reachable from the
 467  * refs we are going to fetch exists and is connected to some of
 468  * our existing refs.
 469  */
 470 static int quickfetch(struct ref *ref_map)
 471 {
 472         struct child_process revlist;
 473         struct ref *ref;
 474         int err;
 475         const char *argv[] = {"rev-list",
 476                 "--quiet", "--objects", "--stdin", "--not", "--all", NULL};
 477
 478         /*
 479          * If we are deepening a shallow clone we already have these
 480          * objects reachable.  Running rev-list here will return with
 481          * a good (0) exit status and we'll bypass the fetch that we
 482          * really need to perform.  Claiming failure now will ensure
 483          * we perform the network exchange to deepen our history.
 484          */
 485         if (depth)
 486                 return -1;
 487
 488         if (!ref_map)
 489                 return 0;
 490
 491         memset(&revlist, 0, sizeof(revlist));
 492         revlist.argv = argv;
 493         revlist.git_cmd = 1;
 494         revlist.no_stdout = 1;
 495         revlist.no_stderr = 1;
 496         revlist.in = -1;
 497
 498         err = start_command(&revlist);
 499         if (err) {
 500                 error(_("could not run rev-list"));
 501                 return err;
 502         }
 503
 504         /*
 505          * If rev-list --stdin encounters an unknown commit, it terminates,
 506          * which will cause SIGPIPE in the write loop below.
 507          */
 508         sigchain_push(SIGPIPE, SIG_IGN);
 509
 510         for (ref = ref_map; ref; ref = ref->next) {
 511                 if (write_in_full(revlist.in, sha1_to_hex(ref->old_sha1), 40) < 0 ||
 512                     write_str_in_full(revlist.in, "\n") < 0) {
 513                         if (errno != EPIPE && errno != EINVAL)
 514                                 error(_("failed write to rev-list: %s"), strerror(errno));
 515                         err = -1;
 516                         break;
 517                 }
 518         }
 519
 520         if (close(revlist.in)) {
 521                 error(_("failed to close rev-list's stdin: %s"), strerror(errno));
 522                 err = -1;
 523         }
 524
 525         sigchain_pop(SIGPIPE);
 526
 527         return finish_command(&revlist) || err;
 528 }
 529
 530 static int fetch_refs(struct transport *transport, struct ref *ref_map)
 531 {
 532         int ret = quickfetch(ref_map);
 533         if (ret)
 534                 ret = transport_fetch_refs(transport, ref_map);
 535         if (!ret)
 536                 ret |= store_updated_refs(transport->url,
 537                                 transport->remote->name,
 538                                 ref_map);
 539         transport_unlock_pack(transport);
 540         return ret;
 541 }
 542
 543 static int prune_refs(struct transport *transport, struct ref *ref_map)
 544 {
 545         int result = 0;
 546         struct ref *ref, *stale_refs = get_stale_heads(transport->remote, ref_map);
 547         const char *dangling_msg = dry_run
 548                 ? _("   (%s will become dangling)\n")
 549                 : _("   (%s has become dangling)\n");
 550
 551         for (ref = stale_refs; ref; ref = ref->next) {
 552                 if (!dry_run)
 553                         result |= delete_ref(ref->name, NULL, 0);
 554                 if (verbosity >= 0) {
 555                         fprintf(stderr, " x %-*s %-*s -> %s\n",
 556                                 TRANSPORT_SUMMARY_WIDTH, _("[deleted]"),
 557                                 REFCOL_WIDTH, _("(none)"), prettify_refname(ref->name));
 558                         warn_dangling_symref(stderr, dangling_msg, ref->name);
 559                 }
 560         }
 561         free_refs(stale_refs);
 562         return result;
 563 }
 564
 565 static int add_existing(const char *refname, const unsigned char *sha1,
 566                         int flag, void *cbdata)
 567 {
 568         struct string_list *list = (struct string_list *)cbdata;
 569         struct string_list_item *item = string_list_insert(list, refname);
 570         item->util = (void *)sha1;
 571         return 0;
 572 }
 573
 574 static int will_fetch(struct ref **head, const unsigned char *sha1)
 575 {
 576         struct ref *rm = *head;
 577         while (rm) {
 578                 if (!hashcmp(rm->old_sha1, sha1))
 579                         return 1;
 580                 rm = rm->next;
 581         }
 582         return 0;
 583 }
 584
 585 static void find_non_local_tags(struct transport *transport,
 586                         struct ref **head,
 587                         struct ref ***tail)
 588 {
 589         struct string_list existing_refs = STRING_LIST_INIT_NODUP;
 590         struct string_list remote_refs = STRING_LIST_INIT_NODUP;
 591         const struct ref *ref;
 592         struct string_list_item *item = NULL;
 593
 594         for_each_ref(add_existing, &existing_refs);
 595         for (ref = transport_get_remote_refs(transport); ref; ref = ref->next) {
 596                 if (prefixcmp(ref->name, "refs/tags"))
 597                         continue;
 598
 599                 /*
 600                  * The peeled ref always follows the matching base
 601                  * ref, so if we see a peeled ref that we don't want
 602                  * to fetch then we can mark the ref entry in the list
 603                  * as one to ignore by setting util to NULL.
 604                  */
 605                 if (!suffixcmp(ref->name, "^{}")) {
 606                         if (item && !has_sha1_file(ref->old_sha1) &&
 607                             !will_fetch(head, ref->old_sha1) &&
 608                             !has_sha1_file(item->util) &&
 609                             !will_fetch(head, item->util))
 610                                 item->util = NULL;
 611                         item = NULL;
 612                         continue;
 613                 }
 614
 615                 /*
 616                  * If item is non-NULL here, then we previously saw a
 617                  * ref not followed by a peeled reference, so we need
 618                  * to check if it is a lightweight tag that we want to
 619                  * fetch.
 620                  */
 621                 if (item && !has_sha1_file(item->util) &&
 622                     !will_fetch(head, item->util))
 623                         item->util = NULL;
 624
 625                 item = NULL;
 626
 627                 /* skip duplicates and refs that we already have */
 628                 if (string_list_has_string(&remote_refs, ref->name) ||
 629                     string_list_has_string(&existing_refs, ref->name))
 630                         continue;
 631
 632                 item = string_list_insert(&remote_refs, ref->name);
 633                 item->util = (void *)ref->old_sha1;
 634         }
 635         string_list_clear(&existing_refs, 0);
 636
 637         /*
 638          * We may have a final lightweight tag that needs to be
 639          * checked to see if it needs fetching.
 640          */
 641         if (item && !has_sha1_file(item->util) &&
 642             !will_fetch(head, item->util))
 643                 item->util = NULL;
 644
 645         /*
 646          * For all the tags in the remote_refs string list,
 647          * add them to the list of refs to be fetched
 648          */
 649         for_each_string_list_item(item, &remote_refs) {
 650                 /* Unless we have already decided to ignore this item... */
 651                 if (item->util)
 652                 {
 653                         struct ref *rm = alloc_ref(item->string);
 654                         rm->peer_ref = alloc_ref(item->string);
 655                         hashcpy(rm->old_sha1, item->util);
 656                         **tail = rm;
 657                         *tail = &rm->next;
 658                 }
 659         }
 660
 661         string_list_clear(&remote_refs, 0);
 662 }
 663
 664 static void check_not_current_branch(struct ref *ref_map)
 665 {
 666         struct branch *current_branch = branch_get(NULL);
 667
 668         if (is_bare_repository() || !current_branch)
 669                 return;
 670
 671         for (; ref_map; ref_map = ref_map->next)
 672                 if (ref_map->peer_ref && !strcmp(current_branch->refname,
 673                                         ref_map->peer_ref->name))
 674                         die(_("Refusing to fetch into current branch %s "
 675                             "of non-bare repository"), current_branch->refname);
 676 }
 677
 678 static int truncate_fetch_head(void)
 679 {
 680         char *filename = git_path("FETCH_HEAD");
 681         FILE *fp = fopen(filename, "w");
 682
 683         if (!fp)
 684                 return error(_("cannot open %s: %s\n"), filename, strerror(errno));
 685         fclose(fp);
 686         return 0;
 687 }
 688
 689 static int do_fetch(struct transport *transport,
 690                     struct refspec *refs, int ref_count)
 691 {
 692         struct string_list existing_refs = STRING_LIST_INIT_NODUP;
 693         struct string_list_item *peer_item = NULL;
 694         struct ref *ref_map;
 695         struct ref *rm;
 696         int autotags = (transport->remote->fetch_tags == 1);
 697
 698         for_each_ref(add_existing, &existing_refs);
 699
 700         if (tags == TAGS_DEFAULT) {
 701                 if (transport->remote->fetch_tags == 2)
 702                         tags = TAGS_SET;
 703                 if (transport->remote->fetch_tags == -1)
 704                         tags = TAGS_UNSET;
 705         }
 706
 707         if (!transport->get_refs_list || !transport->fetch)
 708                 die(_("Don't know how to fetch from %s"), transport->url);
 709
 710         /* if not appending, truncate FETCH_HEAD */
 711         if (!append && !dry_run) {
 712                 int errcode = truncate_fetch_head();
 713                 if (errcode)
 714                         return errcode;
 715         }
 716
 717         ref_map = get_ref_map(transport, refs, ref_count, tags, &autotags);
 718         if (!update_head_ok)
 719                 check_not_current_branch(ref_map);
 720
 721         for (rm = ref_map; rm; rm = rm->next) {
 722                 if (rm->peer_ref) {
 723                         peer_item = string_list_lookup(&existing_refs,
 724                                                        rm->peer_ref->name);
 725                         if (peer_item)
 726                                 hashcpy(rm->peer_ref->old_sha1,
 727                                         peer_item->util);
 728                 }
 729         }
 730
 731         if (tags == TAGS_DEFAULT && autotags)
 732                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
 733         if (fetch_refs(transport, ref_map)) {
 734                 free_refs(ref_map);
 735                 return 1;
 736         }
 737         if (prune)
 738                 prune_refs(transport, ref_map);
 739         free_refs(ref_map);
 740
 741         /* if neither --no-tags nor --tags was specified, do automated tag
 742          * following ... */
 743         if (tags == TAGS_DEFAULT && autotags) {
 744                 struct ref **tail = &ref_map;
 745                 ref_map = NULL;
 746                 find_non_local_tags(transport, &ref_map, &tail);
 747                 if (ref_map) {
 748                         transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, NULL);
 749                         transport_set_option(transport, TRANS_OPT_DEPTH, "0");
 750                         fetch_refs(transport, ref_map);
 751                 }
 752                 free_refs(ref_map);
 753         }
 754
 755         return 0;
 756 }
 757
 758 static void set_option(const char *name, const char *value)
 759 {
 760         int r = transport_set_option(transport, name, value);
 761         if (r < 0)
 762                 die(_("Option \"%s\" value \"%s\" is not valid for %s"),
 763                         name, value, transport->url);
 764         if (r > 0)
 765                 warning(_("Option \"%s\" is ignored for %s\n"),
 766                         name, transport->url);
 767 }
 768
 769 static int get_one_remote_for_fetch(struct remote *remote, void *priv)
 770 {
 771         struct string_list *list = priv;
 772         if (!remote->skip_default_update)
 773                 string_list_append(list, remote->name);
 774         return 0;
 775 }
 776
 777 struct remote_group_data {
 778         const char *name;
 779         struct string_list *list;
 780 };
 781
 782 static int get_remote_group(const char *key, const char *value, void *priv)
 783 {
 784         struct remote_group_data *g = priv;
 785
 786         if (!prefixcmp(key, "remotes.") &&
 787                         !strcmp(key + 8, g->name)) {
 788                 /* split list by white space */
 789                 int space = strcspn(value, " \t\n");
 790                 while (*value) {
 791                         if (space > 1) {
 792                                 string_list_append(g->list,
 793                                                    xstrndup(value, space));
 794                         }
 795                         value += space + (value[space] != '\0');
 796                         space = strcspn(value, " \t\n");
 797                 }
 798         }
 799
 800         return 0;
 801 }
 802
 803 static int add_remote_or_group(const char *name, struct string_list *list)
 804 {
 805         int prev_nr = list->nr;
 806         struct remote_group_data g;
 807         g.name = name; g.list = list;
 808
 809         git_config(get_remote_group, &g);
 810         if (list->nr == prev_nr) {
 811                 struct remote *remote;
 812                 if (!remote_is_configured(name))
 813                         return 0;
 814                 remote = remote_get(name);
 815                 string_list_append(list, remote->name);
 816         }
 817         return 1;
 818 }
 819
 820 static void add_options_to_argv(int *argc, const char **argv)
 821 {
 822         if (dry_run)
 823                 argv[(*argc)++] = "--dry-run";
 824         if (prune)
 825                 argv[(*argc)++] = "--prune";
 826         if (update_head_ok)
 827                 argv[(*argc)++] = "--update-head-ok";
 828         if (force)
 829                 argv[(*argc)++] = "--force";
 830         if (keep)
 831                 argv[(*argc)++] = "--keep";
 832         if (recurse_submodules == RECURSE_SUBMODULES_ON)
 833                 argv[(*argc)++] = "--recurse-submodules";
 834         else if (recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND)
 835                 argv[(*argc)++] = "--recurse-submodules=on-demand";
 836         if (verbosity >= 2)
 837                 argv[(*argc)++] = "-v";
 838         if (verbosity >= 1)
 839                 argv[(*argc)++] = "-v";
 840         else if (verbosity < 0)
 841                 argv[(*argc)++] = "-q";
 842
 843 }
 844
 845 static int fetch_multiple(struct string_list *list)
 846 {
 847         int i, result = 0;
 848         const char *argv[12] = { "fetch", "--append" };
 849         int argc = 2;
 850
 851         add_options_to_argv(&argc, argv);
 852
 853         if (!append && !dry_run) {
 854                 int errcode = truncate_fetch_head();
 855                 if (errcode)
 856                         return errcode;
 857         }
 858
 859         for (i = 0; i < list->nr; i++) {
 860                 const char *name = list->items[i].string;
 861                 argv[argc] = name;
 862                 argv[argc + 1] = NULL;
 863                 if (verbosity >= 0)
 864                         printf(_("Fetching %s\n"), name);
 865                 if (run_command_v_opt(argv, RUN_GIT_CMD)) {
 866                         error(_("Could not fetch %s"), name);
 867                         result = 1;
 868                 }
 869         }
 870
 871         return result;
 872 }
 873
 874 static int fetch_one(struct remote *remote, int argc, const char **argv)
 875 {
 876         int i;
 877         static const char **refs = NULL;
 878         int ref_nr = 0;
 879         int exit_code;
 880
 881         if (!remote)
 882                 die(_("No remote repository specified.  Please, specify either a URL or a\n"
 883                     "remote name from which new revisions should be fetched."));
 884
 885         transport = transport_get(remote, NULL);
 886         transport_set_verbosity(transport, verbosity, progress);
 887         if (upload_pack)
 888                 set_option(TRANS_OPT_UPLOADPACK, upload_pack);
 889         if (keep)
 890                 set_option(TRANS_OPT_KEEP, "yes");
 891         if (depth)
 892                 set_option(TRANS_OPT_DEPTH, depth);
 893
 894         if (argc > 0) {
 895                 int j = 0;
 896                 refs = xcalloc(argc + 1, sizeof(const char *));
 897                 for (i = 0; i < argc; i++) {
 898                         if (!strcmp(argv[i], "tag")) {
 899                                 char *ref;
 900                                 i++;
 901                                 if (i >= argc)
 902                                         die(_("You need to specify a tag name."));
 903                                 ref = xmalloc(strlen(argv[i]) * 2 + 22);
 904                                 strcpy(ref, "refs/tags/");
 905                                 strcat(ref, argv[i]);
 906                                 strcat(ref, ":refs/tags/");
 907                                 strcat(ref, argv[i]);
 908                                 refs[j++] = ref;
 909                         } else
 910                                 refs[j++] = argv[i];
 911                 }
 912                 refs[j] = NULL;
 913                 ref_nr = j;
 914         }
 915
 916         sigchain_push_common(unlock_pack_on_signal);
 917         atexit(unlock_pack);
 918         exit_code = do_fetch(transport,
 919                         parse_fetch_refspec(ref_nr, refs), ref_nr);
 920         transport_disconnect(transport);
 921         transport = NULL;
 922         return exit_code;
 923 }
 924
 925 int cmd_fetch(int argc, const char **argv, const char *prefix)
 926 {
 927         int i;
 928         struct string_list list = STRING_LIST_INIT_NODUP;
 929         struct remote *remote;
 930         int result = 0;
 931
 932         packet_trace_identity("fetch");
 933
 934         /* Record the command line for the reflog */
 935         strbuf_addstr(&default_rla, "fetch");
 936         for (i = 1; i < argc; i++)
 937                 strbuf_addf(&default_rla, " %s", argv[i]);
 938
 939         argc = parse_options(argc, argv, prefix,
 940                              builtin_fetch_options, builtin_fetch_usage, 0);
 941
 942         if (all) {
 943                 if (argc == 1)
 944                         die(_("fetch --all does not take a repository argument"));
 945                 else if (argc > 1)
 946                         die(_("fetch --all does not make sense with refspecs"));
 947                 (void) for_each_remote(get_one_remote_for_fetch, &list);
 948                 result = fetch_multiple(&list);
 949         } else if (argc == 0) {
 950                 /* No arguments -- use default remote */
 951                 remote = remote_get(NULL);
 952                 result = fetch_one(remote, argc, argv);
 953         } else if (multiple) {
 954                 /* All arguments are assumed to be remotes or groups */
 955                 for (i = 0; i < argc; i++)
 956                         if (!add_remote_or_group(argv[i], &list))
 957                                 die(_("No such remote or remote group: %s"), argv[i]);
 958                 result = fetch_multiple(&list);
 959         } else {
 960                 /* Single remote or group */
 961                 (void) add_remote_or_group(argv[0], &list);
 962                 if (list.nr > 1) {
 963                         /* More than one remote */
 964                         if (argc > 1)
 965                                 die(_("Fetching a group and specifying refspecs does not make sense"));
 966                         result = fetch_multiple(&list);
 967                 } else {
 968                         /* Zero or one remotes */
 969                         remote = remote_get(argv[0]);
 970                         result = fetch_one(remote, argc-1, argv+1);
 971                 }
 972         }
 973
 974         if (!result && (recurse_submodules != RECURSE_SUBMODULES_OFF)) {
 975                 const char *options[10];
 976                 int num_options = 0;
 977                 if (recurse_submodules_default) {
 978                         int arg = parse_fetch_recurse_submodules_arg("--recurse-submodules-default", recurse_submodules_default);
 979                         set_config_fetch_recurse_submodules(arg);
 980                 }
 981                 gitmodules_config();
 982                 git_config(submodule_config, NULL);
 983                 add_options_to_argv(&num_options, options);
 984                 result = fetch_populated_submodules(num_options, options,
 985                                                     submodule_prefix,
 986                                                     recurse_submodules,
 987                                                     verbosity < 0);
 988         }
 989
 990         /* All names were strdup()ed or strndup()ed */
 991         list.strdup_strings = 1;
 992         string_list_clear(&list, 0);
 993
 994         return result;
 995 }