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