git.oblomov.eu Git - git/blob - transport.c

   1 #include "cache.h"
   2 #include "transport.h"
   3 #include "run-command.h"
   4 #include "pkt-line.h"
   5 #include "fetch-pack.h"
   6 #include "send-pack.h"
   7 #include "walker.h"
   8 #include "bundle.h"
   9 #include "dir.h"
  10 #include "refs.h"
  11 #include "branch.h"
  12 #include "url.h"
  13 #include "submodule.h"
  14 #include "string-list.h"
  15
  16 /* rsync support */
  17
  18 /*
  19  * We copy packed-refs and refs/ into a temporary file, then read the
  20  * loose refs recursively (sorting whenever possible), and then inserting
  21  * those packed refs that are not yet in the list (not validating, but
  22  * assuming that the file is sorted).
  23  *
  24  * Appears refactoring this from refs.c is too cumbersome.
  25  */
  26
  27 static int str_cmp(const void *a, const void *b)
  28 {
  29         const char *s1 = a;
  30         const char *s2 = b;
  31
  32         return strcmp(s1, s2);
  33 }
  34
  35 /* path->buf + name_offset is expected to point to "refs/" */
  36
  37 static int read_loose_refs(struct strbuf *path, int name_offset,
  38                 struct ref **tail)
  39 {
  40         DIR *dir = opendir(path->buf);
  41         struct dirent *de;
  42         struct {
  43                 char **entries;
  44                 int nr, alloc;
  45         } list;
  46         int i, pathlen;
  47
  48         if (!dir)
  49                 return -1;
  50
  51         memset (&list, 0, sizeof(list));
  52
  53         while ((de = readdir(dir))) {
  54                 if (is_dot_or_dotdot(de->d_name))
  55                         continue;
  56                 ALLOC_GROW(list.entries, list.nr + 1, list.alloc);
  57                 list.entries[list.nr++] = xstrdup(de->d_name);
  58         }
  59         closedir(dir);
  60
  61         /* sort the list */
  62
  63         qsort(list.entries, list.nr, sizeof(char *), str_cmp);
  64
  65         pathlen = path->len;
  66         strbuf_addch(path, '/');
  67
  68         for (i = 0; i < list.nr; i++, strbuf_setlen(path, pathlen + 1)) {
  69                 strbuf_addstr(path, list.entries[i]);
  70                 if (read_loose_refs(path, name_offset, tail)) {
  71                         int fd = open(path->buf, O_RDONLY);
  72                         char buffer[40];
  73                         struct ref *next;
  74
  75                         if (fd < 0)
  76                                 continue;
  77                         next = alloc_ref(path->buf + name_offset);
  78                         if (read_in_full(fd, buffer, 40) != 40 ||
  79                                         get_sha1_hex(buffer, next->old_sha1)) {
  80                                 close(fd);
  81                                 free(next);
  82                                 continue;
  83                         }
  84                         close(fd);
  85                         (*tail)->next = next;
  86                         *tail = next;
  87                 }
  88         }
  89         strbuf_setlen(path, pathlen);
  90
  91         for (i = 0; i < list.nr; i++)
  92                 free(list.entries[i]);
  93         free(list.entries);
  94
  95         return 0;
  96 }
  97
  98 /* insert the packed refs for which no loose refs were found */
  99
 100 static void insert_packed_refs(const char *packed_refs, struct ref **list)
 101 {
 102         FILE *f = fopen(packed_refs, "r");
 103         static char buffer[PATH_MAX];
 104
 105         if (!f)
 106                 return;
 107
 108         for (;;) {
 109                 int cmp = 0; /* assigned before used */
 110                 int len;
 111
 112                 if (!fgets(buffer, sizeof(buffer), f)) {
 113                         fclose(f);
 114                         return;
 115                 }
 116
 117                 if (hexval(buffer[0]) > 0xf)
 118                         continue;
 119                 len = strlen(buffer);
 120                 if (len && buffer[len - 1] == '\n')
 121                         buffer[--len] = '\0';
 122                 if (len < 41)
 123                         continue;
 124                 while ((*list)->next &&
 125                                 (cmp = strcmp(buffer + 41,
 126                                       (*list)->next->name)) > 0)
 127                         list = &(*list)->next;
 128                 if (!(*list)->next || cmp < 0) {
 129                         struct ref *next = alloc_ref(buffer + 41);
 130                         buffer[40] = '\0';
 131                         if (get_sha1_hex(buffer, next->old_sha1)) {
 132                                 warning ("invalid SHA-1: %s", buffer);
 133                                 free(next);
 134                                 continue;
 135                         }
 136                         next->next = (*list)->next;
 137                         (*list)->next = next;
 138                         list = &(*list)->next;
 139                 }
 140         }
 141 }
 142
 143 static void set_upstreams(struct transport *transport, struct ref *refs,
 144         int pretend)
 145 {
 146         struct ref *ref;
 147         for (ref = refs; ref; ref = ref->next) {
 148                 const char *localname;
 149                 const char *tmp;
 150                 const char *remotename;
 151                 unsigned char sha[20];
 152                 int flag = 0;
 153                 /*
 154                  * Check suitability for tracking. Must be successful /
 155                  * already up-to-date ref create/modify (not delete).
 156                  */
 157                 if (ref->status != REF_STATUS_OK &&
 158                         ref->status != REF_STATUS_UPTODATE)
 159                         continue;
 160                 if (!ref->peer_ref)
 161                         continue;
 162                 if (is_null_sha1(ref->new_sha1))
 163                         continue;
 164
 165                 /* Follow symbolic refs (mainly for HEAD). */
 166                 localname = ref->peer_ref->name;
 167                 remotename = ref->name;
 168                 tmp = resolve_ref_unsafe(localname, sha, 1, &flag);
 169                 if (tmp && flag & REF_ISSYMREF &&
 170                         !prefixcmp(tmp, "refs/heads/"))
 171                         localname = tmp;
 172
 173                 /* Both source and destination must be local branches. */
 174                 if (!localname || prefixcmp(localname, "refs/heads/"))
 175                         continue;
 176                 if (!remotename || prefixcmp(remotename, "refs/heads/"))
 177                         continue;
 178
 179                 if (!pretend)
 180                         install_branch_config(BRANCH_CONFIG_VERBOSE,
 181                                 localname + 11, transport->remote->name,
 182                                 remotename);
 183                 else
 184                         printf("Would set upstream of '%s' to '%s' of '%s'\n",
 185                                 localname + 11, remotename + 11,
 186                                 transport->remote->name);
 187         }
 188 }
 189
 190 static const char *rsync_url(const char *url)
 191 {
 192         return prefixcmp(url, "rsync://") ? skip_prefix(url, "rsync:") : url;
 193 }
 194
 195 static struct ref *get_refs_via_rsync(struct transport *transport, int for_push)
 196 {
 197         struct strbuf buf = STRBUF_INIT, temp_dir = STRBUF_INIT;
 198         struct ref dummy = {NULL}, *tail = &dummy;
 199         struct child_process rsync;
 200         const char *args[5];
 201         int temp_dir_len;
 202
 203         if (for_push)
 204                 return NULL;
 205
 206         /* copy the refs to the temporary directory */
 207
 208         strbuf_addstr(&temp_dir, git_path("rsync-refs-XXXXXX"));
 209         if (!mkdtemp(temp_dir.buf))
 210                 die_errno ("Could not make temporary directory");
 211         temp_dir_len = temp_dir.len;
 212
 213         strbuf_addstr(&buf, rsync_url(transport->url));
 214         strbuf_addstr(&buf, "/refs");
 215
 216         memset(&rsync, 0, sizeof(rsync));
 217         rsync.argv = args;
 218         rsync.stdout_to_stderr = 1;
 219         args[0] = "rsync";
 220         args[1] = (transport->verbose > 1) ? "-rv" : "-r";
 221         args[2] = buf.buf;
 222         args[3] = temp_dir.buf;
 223         args[4] = NULL;
 224
 225         if (run_command(&rsync))
 226                 die ("Could not run rsync to get refs");
 227
 228         strbuf_reset(&buf);
 229         strbuf_addstr(&buf, rsync_url(transport->url));
 230         strbuf_addstr(&buf, "/packed-refs");
 231
 232         args[2] = buf.buf;
 233
 234         if (run_command(&rsync))
 235                 die ("Could not run rsync to get refs");
 236
 237         /* read the copied refs */
 238
 239         strbuf_addstr(&temp_dir, "/refs");
 240         read_loose_refs(&temp_dir, temp_dir_len + 1, &tail);
 241         strbuf_setlen(&temp_dir, temp_dir_len);
 242
 243         tail = &dummy;
 244         strbuf_addstr(&temp_dir, "/packed-refs");
 245         insert_packed_refs(temp_dir.buf, &tail);
 246         strbuf_setlen(&temp_dir, temp_dir_len);
 247
 248         if (remove_dir_recursively(&temp_dir, 0))
 249                 warning ("Error removing temporary directory %s.",
 250                                 temp_dir.buf);
 251
 252         strbuf_release(&buf);
 253         strbuf_release(&temp_dir);
 254
 255         return dummy.next;
 256 }
 257
 258 static int fetch_objs_via_rsync(struct transport *transport,
 259                                 int nr_objs, struct ref **to_fetch)
 260 {
 261         struct strbuf buf = STRBUF_INIT;
 262         struct child_process rsync;
 263         const char *args[8];
 264         int result;
 265
 266         strbuf_addstr(&buf, rsync_url(transport->url));
 267         strbuf_addstr(&buf, "/objects/");
 268
 269         memset(&rsync, 0, sizeof(rsync));
 270         rsync.argv = args;
 271         rsync.stdout_to_stderr = 1;
 272         args[0] = "rsync";
 273         args[1] = (transport->verbose > 1) ? "-rv" : "-r";
 274         args[2] = "--ignore-existing";
 275         args[3] = "--exclude";
 276         args[4] = "info";
 277         args[5] = buf.buf;
 278         args[6] = get_object_directory();
 279         args[7] = NULL;
 280
 281         /* NEEDSWORK: handle one level of alternates */
 282         result = run_command(&rsync);
 283
 284         strbuf_release(&buf);
 285
 286         return result;
 287 }
 288
 289 static int write_one_ref(const char *name, const unsigned char *sha1,
 290                 int flags, void *data)
 291 {
 292         struct strbuf *buf = data;
 293         int len = buf->len;
 294         FILE *f;
 295
 296         /* when called via for_each_ref(), flags is non-zero */
 297         if (flags && prefixcmp(name, "refs/heads/") &&
 298                         prefixcmp(name, "refs/tags/"))
 299                 return 0;
 300
 301         strbuf_addstr(buf, name);
 302         if (safe_create_leading_directories(buf->buf) ||
 303                         !(f = fopen(buf->buf, "w")) ||
 304                         fprintf(f, "%s\n", sha1_to_hex(sha1)) < 0 ||
 305                         fclose(f))
 306                 return error("problems writing temporary file %s", buf->buf);
 307         strbuf_setlen(buf, len);
 308         return 0;
 309 }
 310
 311 static int write_refs_to_temp_dir(struct strbuf *temp_dir,
 312                 int refspec_nr, const char **refspec)
 313 {
 314         int i;
 315
 316         for (i = 0; i < refspec_nr; i++) {
 317                 unsigned char sha1[20];
 318                 char *ref;
 319
 320                 if (dwim_ref(refspec[i], strlen(refspec[i]), sha1, &ref) != 1)
 321                         return error("Could not get ref %s", refspec[i]);
 322
 323                 if (write_one_ref(ref, sha1, 0, temp_dir)) {
 324                         free(ref);
 325                         return -1;
 326                 }
 327                 free(ref);
 328         }
 329         return 0;
 330 }
 331
 332 static int rsync_transport_push(struct transport *transport,
 333                 int refspec_nr, const char **refspec, int flags)
 334 {
 335         struct strbuf buf = STRBUF_INIT, temp_dir = STRBUF_INIT;
 336         int result = 0, i;
 337         struct child_process rsync;
 338         const char *args[10];
 339
 340         if (flags & TRANSPORT_PUSH_MIRROR)
 341                 return error("rsync transport does not support mirror mode");
 342
 343         /* first push the objects */
 344
 345         strbuf_addstr(&buf, rsync_url(transport->url));
 346         strbuf_addch(&buf, '/');
 347
 348         memset(&rsync, 0, sizeof(rsync));
 349         rsync.argv = args;
 350         rsync.stdout_to_stderr = 1;
 351         i = 0;
 352         args[i++] = "rsync";
 353         args[i++] = "-a";
 354         if (flags & TRANSPORT_PUSH_DRY_RUN)
 355                 args[i++] = "--dry-run";
 356         if (transport->verbose > 1)
 357                 args[i++] = "-v";
 358         args[i++] = "--ignore-existing";
 359         args[i++] = "--exclude";
 360         args[i++] = "info";
 361         args[i++] = get_object_directory();
 362         args[i++] = buf.buf;
 363         args[i++] = NULL;
 364
 365         if (run_command(&rsync))
 366                 return error("Could not push objects to %s",
 367                                 rsync_url(transport->url));
 368
 369         /* copy the refs to the temporary directory; they could be packed. */
 370
 371         strbuf_addstr(&temp_dir, git_path("rsync-refs-XXXXXX"));
 372         if (!mkdtemp(temp_dir.buf))
 373                 die_errno ("Could not make temporary directory");
 374         strbuf_addch(&temp_dir, '/');
 375
 376         if (flags & TRANSPORT_PUSH_ALL) {
 377                 if (for_each_ref(write_one_ref, &temp_dir))
 378                         return -1;
 379         } else if (write_refs_to_temp_dir(&temp_dir, refspec_nr, refspec))
 380                 return -1;
 381
 382         i = 2;
 383         if (flags & TRANSPORT_PUSH_DRY_RUN)
 384                 args[i++] = "--dry-run";
 385         if (!(flags & TRANSPORT_PUSH_FORCE))
 386                 args[i++] = "--ignore-existing";
 387         args[i++] = temp_dir.buf;
 388         args[i++] = rsync_url(transport->url);
 389         args[i++] = NULL;
 390         if (run_command(&rsync))
 391                 result = error("Could not push to %s",
 392                                 rsync_url(transport->url));
 393
 394         if (remove_dir_recursively(&temp_dir, 0))
 395                 warning ("Could not remove temporary directory %s.",
 396                                 temp_dir.buf);
 397
 398         strbuf_release(&buf);
 399         strbuf_release(&temp_dir);
 400
 401         return result;
 402 }
 403
 404 struct bundle_transport_data {
 405         int fd;
 406         struct bundle_header header;
 407 };
 408
 409 static struct ref *get_refs_from_bundle(struct transport *transport, int for_push)
 410 {
 411         struct bundle_transport_data *data = transport->data;
 412         struct ref *result = NULL;
 413         int i;
 414
 415         if (for_push)
 416                 return NULL;
 417
 418         if (data->fd > 0)
 419                 close(data->fd);
 420         data->fd = read_bundle_header(transport->url, &data->header);
 421         if (data->fd < 0)
 422                 die ("Could not read bundle '%s'.", transport->url);
 423         for (i = 0; i < data->header.references.nr; i++) {
 424                 struct ref_list_entry *e = data->header.references.list + i;
 425                 struct ref *ref = alloc_ref(e->name);
 426                 hashcpy(ref->old_sha1, e->sha1);
 427                 ref->next = result;
 428                 result = ref;
 429         }
 430         return result;
 431 }
 432
 433 static int fetch_refs_from_bundle(struct transport *transport,
 434                                int nr_heads, struct ref **to_fetch)
 435 {
 436         struct bundle_transport_data *data = transport->data;
 437         return unbundle(&data->header, data->fd,
 438                         transport->progress ? BUNDLE_VERBOSE : 0);
 439 }
 440
 441 static int close_bundle(struct transport *transport)
 442 {
 443         struct bundle_transport_data *data = transport->data;
 444         if (data->fd > 0)
 445                 close(data->fd);
 446         free(data);
 447         return 0;
 448 }
 449
 450 struct git_transport_data {
 451         struct git_transport_options options;
 452         struct child_process *conn;
 453         int fd[2];
 454         unsigned got_remote_heads : 1;
 455         struct extra_have_objects extra_have;
 456 };
 457
 458 static int set_git_option(struct git_transport_options *opts,
 459                           const char *name, const char *value)
 460 {
 461         if (!strcmp(name, TRANS_OPT_UPLOADPACK)) {
 462                 opts->uploadpack = value;
 463                 return 0;
 464         } else if (!strcmp(name, TRANS_OPT_RECEIVEPACK)) {
 465                 opts->receivepack = value;
 466                 return 0;
 467         } else if (!strcmp(name, TRANS_OPT_THIN)) {
 468                 opts->thin = !!value;
 469                 return 0;
 470         } else if (!strcmp(name, TRANS_OPT_FOLLOWTAGS)) {
 471                 opts->followtags = !!value;
 472                 return 0;
 473         } else if (!strcmp(name, TRANS_OPT_KEEP)) {
 474                 opts->keep = !!value;
 475                 return 0;
 476         } else if (!strcmp(name, TRANS_OPT_DEPTH)) {
 477                 if (!value)
 478                         opts->depth = 0;
 479                 else {
 480                         char *end;
 481                         opts->depth = strtol(value, &end, 0);
 482                         if (*end)
 483                                 die("transport: invalid depth option '%s'", value);
 484                 }
 485                 return 0;
 486         }
 487         return 1;
 488 }
 489
 490 static int connect_setup(struct transport *transport, int for_push, int verbose)
 491 {
 492         struct git_transport_data *data = transport->data;
 493
 494         if (data->conn)
 495                 return 0;
 496
 497         data->conn = git_connect(data->fd, transport->url,
 498                                  for_push ? data->options.receivepack :
 499                                  data->options.uploadpack,
 500                                  verbose ? CONNECT_VERBOSE : 0);
 501
 502         return 0;
 503 }
 504
 505 static struct ref *get_refs_via_connect(struct transport *transport, int for_push)
 506 {
 507         struct git_transport_data *data = transport->data;
 508         struct ref *refs;
 509
 510         connect_setup(transport, for_push, 0);
 511         get_remote_heads(data->fd[0], NULL, 0, &refs,
 512                          for_push ? REF_NORMAL : 0, &data->extra_have);
 513         data->got_remote_heads = 1;
 514
 515         return refs;
 516 }
 517
 518 static int fetch_refs_via_pack(struct transport *transport,
 519                                int nr_heads, struct ref **to_fetch)
 520 {
 521         struct git_transport_data *data = transport->data;
 522         const struct ref *refs;
 523         char *dest = xstrdup(transport->url);
 524         struct fetch_pack_args args;
 525         struct ref *refs_tmp = NULL;
 526
 527         memset(&args, 0, sizeof(args));
 528         args.uploadpack = data->options.uploadpack;
 529         args.keep_pack = data->options.keep;
 530         args.lock_pack = 1;
 531         args.use_thin_pack = data->options.thin;
 532         args.include_tag = data->options.followtags;
 533         args.verbose = (transport->verbose > 1);
 534         args.quiet = (transport->verbose < 0);
 535         args.no_progress = !transport->progress;
 536         args.depth = data->options.depth;
 537         args.check_self_contained_and_connected =
 538                 data->options.check_self_contained_and_connected;
 539
 540         if (!data->got_remote_heads) {
 541                 connect_setup(transport, 0, 0);
 542                 get_remote_heads(data->fd[0], NULL, 0, &refs_tmp, 0, NULL);
 543                 data->got_remote_heads = 1;
 544         }
 545
 546         refs = fetch_pack(&args, data->fd, data->conn,
 547                           refs_tmp ? refs_tmp : transport->remote_refs,
 548                           dest, to_fetch, nr_heads,
 549                           &transport->pack_lockfile);
 550         close(data->fd[0]);
 551         close(data->fd[1]);
 552         if (finish_connect(data->conn))
 553                 refs = NULL;
 554         data->conn = NULL;
 555         data->got_remote_heads = 0;
 556         data->options.self_contained_and_connected =
 557                 args.self_contained_and_connected;
 558
 559         free_refs(refs_tmp);
 560
 561         free(dest);
 562         return (refs ? 0 : -1);
 563 }
 564
 565 static int push_had_errors(struct ref *ref)
 566 {
 567         for (; ref; ref = ref->next) {
 568                 switch (ref->status) {
 569                 case REF_STATUS_NONE:
 570                 case REF_STATUS_UPTODATE:
 571                 case REF_STATUS_OK:
 572                         break;
 573                 default:
 574                         return 1;
 575                 }
 576         }
 577         return 0;
 578 }
 579
 580 int transport_refs_pushed(struct ref *ref)
 581 {
 582         for (; ref; ref = ref->next) {
 583                 switch(ref->status) {
 584                 case REF_STATUS_NONE:
 585                 case REF_STATUS_UPTODATE:
 586                         break;
 587                 default:
 588                         return 1;
 589                 }
 590         }
 591         return 0;
 592 }
 593
 594 void transport_update_tracking_ref(struct remote *remote, struct ref *ref, int verbose)
 595 {
 596         struct refspec rs;
 597
 598         if (ref->status != REF_STATUS_OK && ref->status != REF_STATUS_UPTODATE)
 599                 return;
 600
 601         rs.src = ref->name;
 602         rs.dst = NULL;
 603
 604         if (!remote_find_tracking(remote, &rs)) {
 605                 if (verbose)
 606                         fprintf(stderr, "updating local tracking ref '%s'\n", rs.dst);
 607                 if (ref->deletion) {
 608                         delete_ref(rs.dst, NULL, 0);
 609                 } else
 610                         update_ref("update by push", rs.dst,
 611                                         ref->new_sha1, NULL, 0, 0);
 612                 free(rs.dst);
 613         }
 614 }
 615
 616 static void print_ref_status(char flag, const char *summary, struct ref *to, struct ref *from, const char *msg, int porcelain)
 617 {
 618         if (porcelain) {
 619                 if (from)
 620                         fprintf(stdout, "%c\t%s:%s\t", flag, from->name, to->name);
 621                 else
 622                         fprintf(stdout, "%c\t:%s\t", flag, to->name);
 623                 if (msg)
 624                         fprintf(stdout, "%s (%s)\n", summary, msg);
 625                 else
 626                         fprintf(stdout, "%s\n", summary);
 627         } else {
 628                 fprintf(stderr, " %c %-*s ", flag, TRANSPORT_SUMMARY_WIDTH, summary);
 629                 if (from)
 630                         fprintf(stderr, "%s -> %s", prettify_refname(from->name), prettify_refname(to->name));
 631                 else
 632                         fputs(prettify_refname(to->name), stderr);
 633                 if (msg) {
 634                         fputs(" (", stderr);
 635                         fputs(msg, stderr);
 636                         fputc(')', stderr);
 637                 }
 638                 fputc('\n', stderr);
 639         }
 640 }
 641
 642 static const char *status_abbrev(unsigned char sha1[20])
 643 {
 644         return find_unique_abbrev(sha1, DEFAULT_ABBREV);
 645 }
 646
 647 static void print_ok_ref_status(struct ref *ref, int porcelain)
 648 {
 649         if (ref->deletion)
 650                 print_ref_status('-', "[deleted]", ref, NULL, NULL, porcelain);
 651         else if (is_null_sha1(ref->old_sha1))
 652                 print_ref_status('*',
 653                         (!prefixcmp(ref->name, "refs/tags/") ? "[new tag]" :
 654                         "[new branch]"),
 655                         ref, ref->peer_ref, NULL, porcelain);
 656         else {
 657                 char quickref[84];
 658                 char type;
 659                 const char *msg;
 660
 661                 strcpy(quickref, status_abbrev(ref->old_sha1));
 662                 if (ref->forced_update) {
 663                         strcat(quickref, "...");
 664                         type = '+';
 665                         msg = "forced update";
 666                 } else {
 667                         strcat(quickref, "..");
 668                         type = ' ';
 669                         msg = NULL;
 670                 }
 671                 strcat(quickref, status_abbrev(ref->new_sha1));
 672
 673                 print_ref_status(type, quickref, ref, ref->peer_ref, msg, porcelain);
 674         }
 675 }
 676
 677 static int print_one_push_status(struct ref *ref, const char *dest, int count, int porcelain)
 678 {
 679         if (!count)
 680                 fprintf(porcelain ? stdout : stderr, "To %s\n", dest);
 681
 682         switch(ref->status) {
 683         case REF_STATUS_NONE:
 684                 print_ref_status('X', "[no match]", ref, NULL, NULL, porcelain);
 685                 break;
 686         case REF_STATUS_REJECT_NODELETE:
 687                 print_ref_status('!', "[rejected]", ref, NULL,
 688                                                  "remote does not support deleting refs", porcelain);
 689                 break;
 690         case REF_STATUS_UPTODATE:
 691                 print_ref_status('=', "[up to date]", ref,
 692                                                  ref->peer_ref, NULL, porcelain);
 693                 break;
 694         case REF_STATUS_REJECT_NONFASTFORWARD:
 695                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
 696                                                  "non-fast-forward", porcelain);
 697                 break;
 698         case REF_STATUS_REJECT_ALREADY_EXISTS:
 699                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
 700                                                  "already exists", porcelain);
 701                 break;
 702         case REF_STATUS_REJECT_FETCH_FIRST:
 703                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
 704                                                  "fetch first", porcelain);
 705                 break;
 706         case REF_STATUS_REJECT_NEEDS_FORCE:
 707                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
 708                                                  "needs force", porcelain);
 709                 break;
 710         case REF_STATUS_REMOTE_REJECT:
 711                 print_ref_status('!', "[remote rejected]", ref,
 712                                                  ref->deletion ? NULL : ref->peer_ref,
 713                                                  ref->remote_status, porcelain);
 714                 break;
 715         case REF_STATUS_EXPECTING_REPORT:
 716                 print_ref_status('!', "[remote failure]", ref,
 717                                                  ref->deletion ? NULL : ref->peer_ref,
 718                                                  "remote failed to report status", porcelain);
 719                 break;
 720         case REF_STATUS_OK:
 721                 print_ok_ref_status(ref, porcelain);
 722                 break;
 723         }
 724
 725         return 1;
 726 }
 727
 728 void transport_print_push_status(const char *dest, struct ref *refs,
 729                                   int verbose, int porcelain, unsigned int *reject_reasons)
 730 {
 731         struct ref *ref;
 732         int n = 0;
 733         unsigned char head_sha1[20];
 734         char *head;
 735
 736         head = resolve_refdup("HEAD", head_sha1, 1, NULL);
 737
 738         if (verbose) {
 739                 for (ref = refs; ref; ref = ref->next)
 740                         if (ref->status == REF_STATUS_UPTODATE)
 741                                 n += print_one_push_status(ref, dest, n, porcelain);
 742         }
 743
 744         for (ref = refs; ref; ref = ref->next)
 745                 if (ref->status == REF_STATUS_OK)
 746                         n += print_one_push_status(ref, dest, n, porcelain);
 747
 748         *reject_reasons = 0;
 749         for (ref = refs; ref; ref = ref->next) {
 750                 if (ref->status != REF_STATUS_NONE &&
 751                     ref->status != REF_STATUS_UPTODATE &&
 752                     ref->status != REF_STATUS_OK)
 753                         n += print_one_push_status(ref, dest, n, porcelain);
 754                 if (ref->status == REF_STATUS_REJECT_NONFASTFORWARD) {
 755                         if (head != NULL && !strcmp(head, ref->name))
 756                                 *reject_reasons |= REJECT_NON_FF_HEAD;
 757                         else
 758                                 *reject_reasons |= REJECT_NON_FF_OTHER;
 759                 } else if (ref->status == REF_STATUS_REJECT_ALREADY_EXISTS) {
 760                         *reject_reasons |= REJECT_ALREADY_EXISTS;
 761                 } else if (ref->status == REF_STATUS_REJECT_FETCH_FIRST) {
 762                         *reject_reasons |= REJECT_FETCH_FIRST;
 763                 } else if (ref->status == REF_STATUS_REJECT_NEEDS_FORCE) {
 764                         *reject_reasons |= REJECT_NEEDS_FORCE;
 765                 }
 766         }
 767 }
 768
 769 void transport_verify_remote_names(int nr_heads, const char **heads)
 770 {
 771         int i;
 772
 773         for (i = 0; i < nr_heads; i++) {
 774                 const char *local = heads[i];
 775                 const char *remote = strrchr(heads[i], ':');
 776
 777                 if (*local == '+')
 778                         local++;
 779
 780                 /* A matching refspec is okay.  */
 781                 if (remote == local && remote[1] == '\0')
 782                         continue;
 783
 784                 remote = remote ? (remote + 1) : local;
 785                 if (check_refname_format(remote,
 786                                 REFNAME_ALLOW_ONELEVEL|REFNAME_REFSPEC_PATTERN))
 787                         die("remote part of refspec is not a valid name in %s",
 788                                 heads[i]);
 789         }
 790 }
 791
 792 static int git_transport_push(struct transport *transport, struct ref *remote_refs, int flags)
 793 {
 794         struct git_transport_data *data = transport->data;
 795         struct send_pack_args args;
 796         int ret;
 797
 798         if (!data->got_remote_heads) {
 799                 struct ref *tmp_refs;
 800                 connect_setup(transport, 1, 0);
 801
 802                 get_remote_heads(data->fd[0], NULL, 0, &tmp_refs, REF_NORMAL, NULL);
 803                 data->got_remote_heads = 1;
 804         }
 805
 806         memset(&args, 0, sizeof(args));
 807         args.send_mirror = !!(flags & TRANSPORT_PUSH_MIRROR);
 808         args.force_update = !!(flags & TRANSPORT_PUSH_FORCE);
 809         args.use_thin_pack = data->options.thin;
 810         args.verbose = (transport->verbose > 0);
 811         args.quiet = (transport->verbose < 0);
 812         args.progress = transport->progress;
 813         args.dry_run = !!(flags & TRANSPORT_PUSH_DRY_RUN);
 814         args.porcelain = !!(flags & TRANSPORT_PUSH_PORCELAIN);
 815
 816         ret = send_pack(&args, data->fd, data->conn, remote_refs,
 817                         &data->extra_have);
 818
 819         close(data->fd[1]);
 820         close(data->fd[0]);
 821         ret |= finish_connect(data->conn);
 822         data->conn = NULL;
 823         data->got_remote_heads = 0;
 824
 825         return ret;
 826 }
 827
 828 static int connect_git(struct transport *transport, const char *name,
 829                        const char *executable, int fd[2])
 830 {
 831         struct git_transport_data *data = transport->data;
 832         data->conn = git_connect(data->fd, transport->url,
 833                                  executable, 0);
 834         fd[0] = data->fd[0];
 835         fd[1] = data->fd[1];
 836         return 0;
 837 }
 838
 839 static int disconnect_git(struct transport *transport)
 840 {
 841         struct git_transport_data *data = transport->data;
 842         if (data->conn) {
 843                 if (data->got_remote_heads)
 844                         packet_flush(data->fd[1]);
 845                 close(data->fd[0]);
 846                 close(data->fd[1]);
 847                 finish_connect(data->conn);
 848         }
 849
 850         free(data);
 851         return 0;
 852 }
 853
 854 void transport_take_over(struct transport *transport,
 855                          struct child_process *child)
 856 {
 857         struct git_transport_data *data;
 858
 859         if (!transport->smart_options)
 860                 die("Bug detected: Taking over transport requires non-NULL "
 861                     "smart_options field.");
 862
 863         data = xcalloc(1, sizeof(*data));
 864         data->options = *transport->smart_options;
 865         data->conn = child;
 866         data->fd[0] = data->conn->out;
 867         data->fd[1] = data->conn->in;
 868         data->got_remote_heads = 0;
 869         transport->data = data;
 870
 871         transport->set_option = NULL;
 872         transport->get_refs_list = get_refs_via_connect;
 873         transport->fetch = fetch_refs_via_pack;
 874         transport->push = NULL;
 875         transport->push_refs = git_transport_push;
 876         transport->disconnect = disconnect_git;
 877         transport->smart_options = &(data->options);
 878 }
 879
 880 static int is_local(const char *url)
 881 {
 882         const char *colon = strchr(url, ':');
 883         const char *slash = strchr(url, '/');
 884         return !colon || (slash && slash < colon) ||
 885                 has_dos_drive_prefix(url);
 886 }
 887
 888 static int is_file(const char *url)
 889 {
 890         struct stat buf;
 891         if (stat(url, &buf))
 892                 return 0;
 893         return S_ISREG(buf.st_mode);
 894 }
 895
 896 static int external_specification_len(const char *url)
 897 {
 898         return strchr(url, ':') - url;
 899 }
 900
 901 struct transport *transport_get(struct remote *remote, const char *url)
 902 {
 903         const char *helper;
 904         struct transport *ret = xcalloc(1, sizeof(*ret));
 905
 906         ret->progress = isatty(2);
 907
 908         if (!remote)
 909                 die("No remote provided to transport_get()");
 910
 911         ret->got_remote_refs = 0;
 912         ret->remote = remote;
 913         helper = remote->foreign_vcs;
 914
 915         if (!url && remote->url)
 916                 url = remote->url[0];
 917         ret->url = url;
 918
 919         /* maybe it is a foreign URL? */
 920         if (url) {
 921                 const char *p = url;
 922
 923                 while (is_urlschemechar(p == url, *p))
 924                         p++;
 925                 if (!prefixcmp(p, "::"))
 926                         helper = xstrndup(url, p - url);
 927         }
 928
 929         if (helper) {
 930                 transport_helper_init(ret, helper);
 931         } else if (!prefixcmp(url, "rsync:")) {
 932                 ret->get_refs_list = get_refs_via_rsync;
 933                 ret->fetch = fetch_objs_via_rsync;
 934                 ret->push = rsync_transport_push;
 935                 ret->smart_options = NULL;
 936         } else if (is_local(url) && is_file(url) && is_bundle(url, 1)) {
 937                 struct bundle_transport_data *data = xcalloc(1, sizeof(*data));
 938                 ret->data = data;
 939                 ret->get_refs_list = get_refs_from_bundle;
 940                 ret->fetch = fetch_refs_from_bundle;
 941                 ret->disconnect = close_bundle;
 942                 ret->smart_options = NULL;
 943         } else if (!is_url(url)
 944                 || !prefixcmp(url, "file://")
 945                 || !prefixcmp(url, "git://")
 946                 || !prefixcmp(url, "ssh://")
 947                 || !prefixcmp(url, "git+ssh://")
 948                 || !prefixcmp(url, "ssh+git://")) {
 949                 /* These are builtin smart transports. */
 950                 struct git_transport_data *data = xcalloc(1, sizeof(*data));
 951                 ret->data = data;
 952                 ret->set_option = NULL;
 953                 ret->get_refs_list = get_refs_via_connect;
 954                 ret->fetch = fetch_refs_via_pack;
 955                 ret->push_refs = git_transport_push;
 956                 ret->connect = connect_git;
 957                 ret->disconnect = disconnect_git;
 958                 ret->smart_options = &(data->options);
 959
 960                 data->conn = NULL;
 961                 data->got_remote_heads = 0;
 962         } else {
 963                 /* Unknown protocol in URL. Pass to external handler. */
 964                 int len = external_specification_len(url);
 965                 char *handler = xmalloc(len + 1);
 966                 handler[len] = 0;
 967                 strncpy(handler, url, len);
 968                 transport_helper_init(ret, handler);
 969         }
 970
 971         if (ret->smart_options) {
 972                 ret->smart_options->thin = 1;
 973                 ret->smart_options->uploadpack = "git-upload-pack";
 974                 if (remote->uploadpack)
 975                         ret->smart_options->uploadpack = remote->uploadpack;
 976                 ret->smart_options->receivepack = "git-receive-pack";
 977                 if (remote->receivepack)
 978                         ret->smart_options->receivepack = remote->receivepack;
 979         }
 980
 981         return ret;
 982 }
 983
 984 int transport_set_option(struct transport *transport,
 985                          const char *name, const char *value)
 986 {
 987         int git_reports = 1, protocol_reports = 1;
 988
 989         if (transport->smart_options)
 990                 git_reports = set_git_option(transport->smart_options,
 991                                              name, value);
 992
 993         if (transport->set_option)
 994                 protocol_reports = transport->set_option(transport, name,
 995                                                         value);
 996
 997         /* If either report is 0, report 0 (success). */
 998         if (!git_reports || !protocol_reports)
 999                 return 0;
1000         /* If either reports -1 (invalid value), report -1. */
1001         if ((git_reports == -1) || (protocol_reports == -1))
1002                 return -1;
1003         /* Otherwise if both report unknown, report unknown. */
1004         return 1;
1005 }
1006
1007 void transport_set_verbosity(struct transport *transport, int verbosity,
1008         int force_progress)
1009 {
1010         if (verbosity >= 1)
1011                 transport->verbose = verbosity <= 3 ? verbosity : 3;
1012         if (verbosity < 0)
1013                 transport->verbose = -1;
1014
1015         /**
1016          * Rules used to determine whether to report progress (processing aborts
1017          * when a rule is satisfied):
1018          *
1019          *   . Report progress, if force_progress is 1 (ie. --progress).
1020          *   . Don't report progress, if force_progress is 0 (ie. --no-progress).
1021          *   . Don't report progress, if verbosity < 0 (ie. -q/--quiet ).
1022          *   . Report progress if isatty(2) is 1.
1023          **/
1024         if (force_progress >= 0)
1025                 transport->progress = !!force_progress;
1026         else
1027                 transport->progress = verbosity >= 0 && isatty(2);
1028 }
1029
1030 static void die_with_unpushed_submodules(struct string_list *needs_pushing)
1031 {
1032         int i;
1033
1034         fprintf(stderr, "The following submodule paths contain changes that can\n"
1035                         "not be found on any remote:\n");
1036         for (i = 0; i < needs_pushing->nr; i++)
1037                 printf("  %s\n", needs_pushing->items[i].string);
1038         fprintf(stderr, "\nPlease try\n\n"
1039                         "       git push --recurse-submodules=on-demand\n\n"
1040                         "or cd to the path and use\n\n"
1041                         "       git push\n\n"
1042                         "to push them to a remote.\n\n");
1043
1044         string_list_clear(needs_pushing, 0);
1045
1046         die("Aborting.");
1047 }
1048
1049 static int run_pre_push_hook(struct transport *transport,
1050                              struct ref *remote_refs)
1051 {
1052         int ret = 0, x;
1053         struct ref *r;
1054         struct child_process proc;
1055         struct strbuf buf;
1056         const char *argv[4];
1057
1058         if (!(argv[0] = find_hook("pre-push")))
1059                 return 0;
1060
1061         argv[1] = transport->remote->name;
1062         argv[2] = transport->url;
1063         argv[3] = NULL;
1064
1065         memset(&proc, 0, sizeof(proc));
1066         proc.argv = argv;
1067         proc.in = -1;
1068
1069         if (start_command(&proc)) {
1070                 finish_command(&proc);
1071                 return -1;
1072         }
1073
1074         strbuf_init(&buf, 256);
1075
1076         for (r = remote_refs; r; r = r->next) {
1077                 if (!r->peer_ref) continue;
1078                 if (r->status == REF_STATUS_REJECT_NONFASTFORWARD) continue;
1079                 if (r->status == REF_STATUS_UPTODATE) continue;
1080
1081                 strbuf_reset(&buf);
1082                 strbuf_addf( &buf, "%s %s %s %s\n",
1083                          r->peer_ref->name, sha1_to_hex(r->new_sha1),
1084                          r->name, sha1_to_hex(r->old_sha1));
1085
1086                 if (write_in_full(proc.in, buf.buf, buf.len) != buf.len) {
1087                         ret = -1;
1088                         break;
1089                 }
1090         }
1091
1092         strbuf_release(&buf);
1093
1094         x = close(proc.in);
1095         if (!ret)
1096                 ret = x;
1097
1098         x = finish_command(&proc);
1099         if (!ret)
1100                 ret = x;
1101
1102         return ret;
1103 }
1104
1105 int transport_push(struct transport *transport,
1106                    int refspec_nr, const char **refspec, int flags,
1107                    unsigned int *reject_reasons)
1108 {
1109         *reject_reasons = 0;
1110         transport_verify_remote_names(refspec_nr, refspec);
1111
1112         if (transport->push) {
1113                 /* Maybe FIXME. But no important transport uses this case. */
1114                 if (flags & TRANSPORT_PUSH_SET_UPSTREAM)
1115                         die("This transport does not support using --set-upstream");
1116
1117                 return transport->push(transport, refspec_nr, refspec, flags);
1118         } else if (transport->push_refs) {
1119                 struct ref *remote_refs =
1120                         transport->get_refs_list(transport, 1);
1121                 struct ref *local_refs = get_local_heads();
1122                 int match_flags = MATCH_REFS_NONE;
1123                 int verbose = (transport->verbose > 0);
1124                 int quiet = (transport->verbose < 0);
1125                 int porcelain = flags & TRANSPORT_PUSH_PORCELAIN;
1126                 int pretend = flags & TRANSPORT_PUSH_DRY_RUN;
1127                 int push_ret, ret, err;
1128
1129                 if (flags & TRANSPORT_PUSH_ALL)
1130                         match_flags |= MATCH_REFS_ALL;
1131                 if (flags & TRANSPORT_PUSH_MIRROR)
1132                         match_flags |= MATCH_REFS_MIRROR;
1133                 if (flags & TRANSPORT_PUSH_PRUNE)
1134                         match_flags |= MATCH_REFS_PRUNE;
1135                 if (flags & TRANSPORT_PUSH_FOLLOW_TAGS)
1136                         match_flags |= MATCH_REFS_FOLLOW_TAGS;
1137
1138                 if (match_push_refs(local_refs, &remote_refs,
1139                                     refspec_nr, refspec, match_flags)) {
1140                         return -1;
1141                 }
1142
1143                 set_ref_status_for_push(remote_refs,
1144                         flags & TRANSPORT_PUSH_MIRROR,
1145                         flags & TRANSPORT_PUSH_FORCE);
1146
1147                 if (!(flags & TRANSPORT_PUSH_NO_HOOK))
1148                         if (run_pre_push_hook(transport, remote_refs))
1149                                 return -1;
1150
1151                 if ((flags & TRANSPORT_RECURSE_SUBMODULES_ON_DEMAND) && !is_bare_repository()) {
1152                         struct ref *ref = remote_refs;
1153                         for (; ref; ref = ref->next)
1154                                 if (!is_null_sha1(ref->new_sha1) &&
1155                                     !push_unpushed_submodules(ref->new_sha1,
1156                                             transport->remote->name))
1157                                     die ("Failed to push all needed submodules!");
1158                 }
1159
1160                 if ((flags & (TRANSPORT_RECURSE_SUBMODULES_ON_DEMAND |
1161                               TRANSPORT_RECURSE_SUBMODULES_CHECK)) && !is_bare_repository()) {
1162                         struct ref *ref = remote_refs;
1163                         struct string_list needs_pushing;
1164
1165                         memset(&needs_pushing, 0, sizeof(struct string_list));
1166                         needs_pushing.strdup_strings = 1;
1167                         for (; ref; ref = ref->next)
1168                                 if (!is_null_sha1(ref->new_sha1) &&
1169                                     find_unpushed_submodules(ref->new_sha1,
1170                                             transport->remote->name, &needs_pushing))
1171                                         die_with_unpushed_submodules(&needs_pushing);
1172                 }
1173
1174                 push_ret = transport->push_refs(transport, remote_refs, flags);
1175                 err = push_had_errors(remote_refs);
1176                 ret = push_ret | err;
1177
1178                 if (!quiet || err)
1179                         transport_print_push_status(transport->url, remote_refs,
1180                                         verbose | porcelain, porcelain,
1181                                         reject_reasons);
1182
1183                 if (flags & TRANSPORT_PUSH_SET_UPSTREAM)
1184                         set_upstreams(transport, remote_refs, pretend);
1185
1186                 if (!(flags & TRANSPORT_PUSH_DRY_RUN)) {
1187                         struct ref *ref;
1188                         for (ref = remote_refs; ref; ref = ref->next)
1189                                 transport_update_tracking_ref(transport->remote, ref, verbose);
1190                 }
1191
1192                 if (porcelain && !push_ret)
1193                         puts("Done");
1194                 else if (!quiet && !ret && !transport_refs_pushed(remote_refs))
1195                         fprintf(stderr, "Everything up-to-date\n");
1196
1197                 return ret;
1198         }
1199         return 1;
1200 }
1201
1202 const struct ref *transport_get_remote_refs(struct transport *transport)
1203 {
1204         if (!transport->got_remote_refs) {
1205                 transport->remote_refs = transport->get_refs_list(transport, 0);
1206                 transport->got_remote_refs = 1;
1207         }
1208
1209         return transport->remote_refs;
1210 }
1211
1212 int transport_fetch_refs(struct transport *transport, struct ref *refs)
1213 {
1214         int rc;
1215         int nr_heads = 0, nr_alloc = 0, nr_refs = 0;
1216         struct ref **heads = NULL;
1217         struct ref *rm;
1218
1219         for (rm = refs; rm; rm = rm->next) {
1220                 nr_refs++;
1221                 if (rm->peer_ref &&
1222                     !is_null_sha1(rm->old_sha1) &&
1223                     !hashcmp(rm->peer_ref->old_sha1, rm->old_sha1))
1224                         continue;
1225                 ALLOC_GROW(heads, nr_heads + 1, nr_alloc);
1226                 heads[nr_heads++] = rm;
1227         }
1228
1229         if (!nr_heads) {
1230                 /*
1231                  * When deepening of a shallow repository is requested,
1232                  * then local and remote refs are likely to still be equal.
1233                  * Just feed them all to the fetch method in that case.
1234                  * This condition shouldn't be met in a non-deepening fetch
1235                  * (see builtin/fetch.c:quickfetch()).
1236                  */
1237                 heads = xmalloc(nr_refs * sizeof(*heads));
1238                 for (rm = refs; rm; rm = rm->next)
1239                         heads[nr_heads++] = rm;
1240         }
1241
1242         rc = transport->fetch(transport, nr_heads, heads);
1243
1244         free(heads);
1245         return rc;
1246 }
1247
1248 void transport_unlock_pack(struct transport *transport)
1249 {
1250         if (transport->pack_lockfile) {
1251                 unlink_or_warn(transport->pack_lockfile);
1252                 free(transport->pack_lockfile);
1253                 transport->pack_lockfile = NULL;
1254         }
1255 }
1256
1257 int transport_connect(struct transport *transport, const char *name,
1258                       const char *exec, int fd[2])
1259 {
1260         if (transport->connect)
1261                 return transport->connect(transport, name, exec, fd);
1262         else
1263                 die("Operation not supported by protocol");
1264 }
1265
1266 int transport_disconnect(struct transport *transport)
1267 {
1268         int ret = 0;
1269         if (transport->disconnect)
1270                 ret = transport->disconnect(transport);
1271         free(transport);
1272         return ret;
1273 }
1274
1275 /*
1276  * Strip username (and password) from a URL and return
1277  * it in a newly allocated string.
1278  */
1279 char *transport_anonymize_url(const char *url)
1280 {
1281         char *anon_url, *scheme_prefix, *anon_part;
1282         size_t anon_len, prefix_len = 0;
1283
1284         anon_part = strchr(url, '@');
1285         if (is_local(url) || !anon_part)
1286                 goto literal_copy;
1287
1288         anon_len = strlen(++anon_part);
1289         scheme_prefix = strstr(url, "://");
1290         if (!scheme_prefix) {
1291                 if (!strchr(anon_part, ':'))
1292                         /* cannot be "me@there:/path/name" */
1293                         goto literal_copy;
1294         } else {
1295                 const char *cp;
1296                 /* make sure scheme is reasonable */
1297                 for (cp = url; cp < scheme_prefix; cp++) {
1298                         switch (*cp) {
1299                                 /* RFC 1738 2.1 */
1300                         case '+': case '.': case '-':
1301                                 break; /* ok */
1302                         default:
1303                                 if (isalnum(*cp))
1304                                         break;
1305                                 /* it isn't */
1306                                 goto literal_copy;
1307                         }
1308                 }
1309                 /* @ past the first slash does not count */
1310                 cp = strchr(scheme_prefix + 3, '/');
1311                 if (cp && cp < anon_part)
1312                         goto literal_copy;
1313                 prefix_len = scheme_prefix - url + 3;
1314         }
1315         anon_url = xcalloc(1, 1 + prefix_len + anon_len);
1316         memcpy(anon_url, url, prefix_len);
1317         memcpy(anon_url + prefix_len, anon_part, anon_len);
1318         return anon_url;
1319 literal_copy:
1320         return xstrdup(url);
1321 }
1322
1323 struct alternate_refs_data {
1324         alternate_ref_fn *fn;
1325         void *data;
1326 };
1327
1328 static int refs_from_alternate_cb(struct alternate_object_database *e,
1329                                   void *data)
1330 {
1331         char *other;
1332         size_t len;
1333         struct remote *remote;
1334         struct transport *transport;
1335         const struct ref *extra;
1336         struct alternate_refs_data *cb = data;
1337
1338         e->name[-1] = '\0';
1339         other = xstrdup(real_path(e->base));
1340         e->name[-1] = '/';
1341         len = strlen(other);
1342
1343         while (other[len-1] == '/')
1344                 other[--len] = '\0';
1345         if (len < 8 || memcmp(other + len - 8, "/objects", 8))
1346                 return 0;
1347         /* Is this a git repository with refs? */
1348         memcpy(other + len - 8, "/refs", 6);
1349         if (!is_directory(other))
1350                 return 0;
1351         other[len - 8] = '\0';
1352         remote = remote_get(other);
1353         transport = transport_get(remote, other);
1354         for (extra = transport_get_remote_refs(transport);
1355              extra;
1356              extra = extra->next)
1357                 cb->fn(extra, cb->data);
1358         transport_disconnect(transport);
1359         free(other);
1360         return 0;
1361 }
1362
1363 void for_each_alternate_ref(alternate_ref_fn fn, void *data)
1364 {
1365         struct alternate_refs_data cb;
1366         cb.fn = fn;
1367         cb.data = data;
1368         foreach_alt_odb(refs_from_alternate_cb, &cb);
1369 }