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