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