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 "remote.h"
   7 #include "connect.h"
   8 #include "send-pack.h"
   9 #include "walker.h"
  10 #include "bundle.h"
  11 #include "dir.h"
  12 #include "refs.h"
  13 #include "branch.h"
  14 #include "url.h"
  15 #include "submodule.h"
  16 #include "string-list.h"
  17 #include "sha1-array.h"
  18
  19 /* rsync support */
  20
  21 /*
  22  * We copy packed-refs and refs/ into a temporary file, then read the
  23  * loose refs recursively (sorting whenever possible), and then inserting
  24  * those packed refs that are not yet in the list (not validating, but
  25  * assuming that the file is sorted).
  26  *
  27  * Appears refactoring this from refs.c is too cumbersome.
  28  */
  29
  30 static int str_cmp(const void *a, const void *b)
  31 {
  32         const char *s1 = a;
  33         const char *s2 = b;
  34
  35         return strcmp(s1, s2);
  36 }
  37
  38 /* path->buf + name_offset is expected to point to "refs/" */
  39
  40 static int read_loose_refs(struct strbuf *path, int name_offset,
  41                 struct ref **tail)
  42 {
  43         DIR *dir = opendir(path->buf);
  44         struct dirent *de;
  45         struct {
  46                 char **entries;
  47                 int nr, alloc;
  48         } list;
  49         int i, pathlen;
  50
  51         if (!dir)
  52                 return -1;
  53
  54         memset (&list, 0, sizeof(list));
  55
  56         while ((de = readdir(dir))) {
  57                 if (is_dot_or_dotdot(de->d_name))
  58                         continue;
  59                 ALLOC_GROW(list.entries, list.nr + 1, list.alloc);
  60                 list.entries[list.nr++] = xstrdup(de->d_name);
  61         }
  62         closedir(dir);
  63
  64         /* sort the list */
  65
  66         qsort(list.entries, list.nr, sizeof(char *), str_cmp);
  67
  68         pathlen = path->len;
  69         strbuf_addch(path, '/');
  70
  71         for (i = 0; i < list.nr; i++, strbuf_setlen(path, pathlen + 1)) {
  72                 strbuf_addstr(path, list.entries[i]);
  73                 if (read_loose_refs(path, name_offset, tail)) {
  74                         int fd = open(path->buf, O_RDONLY);
  75                         char buffer[40];
  76                         struct ref *next;
  77
  78                         if (fd < 0)
  79                                 continue;
  80                         next = alloc_ref(path->buf + name_offset);
  81                         if (read_in_full(fd, buffer, 40) != 40 ||
  82                                         get_sha1_hex(buffer, next->old_sha1)) {
  83                                 close(fd);
  84                                 free(next);
  85                                 continue;
  86                         }
  87                         close(fd);
  88                         (*tail)->next = next;
  89                         *tail = next;
  90                 }
  91         }
  92         strbuf_setlen(path, pathlen);
  93
  94         for (i = 0; i < list.nr; i++)
  95                 free(list.entries[i]);
  96         free(list.entries);
  97
  98         return 0;
  99 }
 100
 101 /* insert the packed refs for which no loose refs were found */
 102
 103 static void insert_packed_refs(const char *packed_refs, struct ref **list)
 104 {
 105         FILE *f = fopen(packed_refs, "r");
 106         static char buffer[PATH_MAX];
 107
 108         if (!f)
 109                 return;
 110
 111         for (;;) {
 112                 int cmp = 0; /* assigned before used */
 113                 int len;
 114
 115                 if (!fgets(buffer, sizeof(buffer), f)) {
 116                         fclose(f);
 117                         return;
 118                 }
 119
 120                 if (!isxdigit(buffer[0]))
 121                         continue;
 122                 len = strlen(buffer);
 123                 if (len && buffer[len - 1] == '\n')
 124                         buffer[--len] = '\0';
 125                 if (len < 41)
 126                         continue;
 127                 while ((*list)->next &&
 128                                 (cmp = strcmp(buffer + 41,
 129                                       (*list)->next->name)) > 0)
 130                         list = &(*list)->next;
 131                 if (!(*list)->next || cmp < 0) {
 132                         struct ref *next = alloc_ref(buffer + 41);
 133                         buffer[40] = '\0';
 134                         if (get_sha1_hex(buffer, next->old_sha1)) {
 135                                 warning ("invalid SHA-1: %s", buffer);
 136                                 free(next);
 137                                 continue;
 138                         }
 139                         next->next = (*list)->next;
 140                         (*list)->next = next;
 141                         list = &(*list)->next;
 142                 }
 143         }
 144 }
 145
 146 static void set_upstreams(struct transport *transport, struct ref *refs,
 147         int pretend)
 148 {
 149         struct ref *ref;
 150         for (ref = refs; ref; ref = ref->next) {
 151                 const char *localname;
 152                 const char *tmp;
 153                 const char *remotename;
 154                 unsigned char sha[20];
 155                 int flag = 0;
 156                 /*
 157                  * Check suitability for tracking. Must be successful /
 158                  * already up-to-date ref create/modify (not delete).
 159                  */
 160                 if (ref->status != REF_STATUS_OK &&
 161                         ref->status != REF_STATUS_UPTODATE)
 162                         continue;
 163                 if (!ref->peer_ref)
 164                         continue;
 165                 if (is_null_sha1(ref->new_sha1))
 166                         continue;
 167
 168                 /* Follow symbolic refs (mainly for HEAD). */
 169                 localname = ref->peer_ref->name;
 170                 remotename = ref->name;
 171                 tmp = resolve_ref_unsafe(localname, RESOLVE_REF_READING,
 172                                          sha, &flag);
 173                 if (tmp && flag & REF_ISSYMREF &&
 174                         starts_with(tmp, "refs/heads/"))
 175                         localname = tmp;
 176
 177                 /* Both source and destination must be local branches. */
 178                 if (!localname || !starts_with(localname, "refs/heads/"))
 179                         continue;
 180                 if (!remotename || !starts_with(remotename, "refs/heads/"))
 181                         continue;
 182
 183                 if (!pretend)
 184                         install_branch_config(BRANCH_CONFIG_VERBOSE,
 185                                 localname + 11, transport->remote->name,
 186                                 remotename);
 187                 else
 188                         printf("Would set upstream of '%s' to '%s' of '%s'\n",
 189                                 localname + 11, remotename + 11,
 190                                 transport->remote->name);
 191         }
 192 }
 193
 194 static const char *rsync_url(const char *url)
 195 {
 196         if (!starts_with(url, "rsync://"))
 197                 skip_prefix(url, "rsync:", &url);
 198         return url;
 199 }
 200
 201 static struct ref *get_refs_via_rsync(struct transport *transport, int for_push)
 202 {
 203         struct strbuf buf = STRBUF_INIT, temp_dir = STRBUF_INIT;
 204         struct ref dummy = {NULL}, *tail = &dummy;
 205         struct child_process rsync = CHILD_PROCESS_INIT;
 206         const char *args[5];
 207         int temp_dir_len;
 208
 209         if (for_push)
 210                 return NULL;
 211
 212         /* copy the refs to the temporary directory */
 213
 214         strbuf_addstr(&temp_dir, git_path("rsync-refs-XXXXXX"));
 215         if (!mkdtemp(temp_dir.buf))
 216                 die_errno ("Could not make temporary directory");
 217         temp_dir_len = temp_dir.len;
 218
 219         strbuf_addstr(&buf, rsync_url(transport->url));
 220         strbuf_addstr(&buf, "/refs");
 221
 222         rsync.argv = args;
 223         rsync.stdout_to_stderr = 1;
 224         args[0] = "rsync";
 225         args[1] = (transport->verbose > 1) ? "-rv" : "-r";
 226         args[2] = buf.buf;
 227         args[3] = temp_dir.buf;
 228         args[4] = NULL;
 229
 230         if (run_command(&rsync))
 231                 die ("Could not run rsync to get refs");
 232
 233         strbuf_reset(&buf);
 234         strbuf_addstr(&buf, rsync_url(transport->url));
 235         strbuf_addstr(&buf, "/packed-refs");
 236
 237         args[2] = buf.buf;
 238
 239         if (run_command(&rsync))
 240                 die ("Could not run rsync to get refs");
 241
 242         /* read the copied refs */
 243
 244         strbuf_addstr(&temp_dir, "/refs");
 245         read_loose_refs(&temp_dir, temp_dir_len + 1, &tail);
 246         strbuf_setlen(&temp_dir, temp_dir_len);
 247
 248         tail = &dummy;
 249         strbuf_addstr(&temp_dir, "/packed-refs");
 250         insert_packed_refs(temp_dir.buf, &tail);
 251         strbuf_setlen(&temp_dir, temp_dir_len);
 252
 253         if (remove_dir_recursively(&temp_dir, 0))
 254                 warning ("Error removing temporary directory %s.",
 255                                 temp_dir.buf);
 256
 257         strbuf_release(&buf);
 258         strbuf_release(&temp_dir);
 259
 260         return dummy.next;
 261 }
 262
 263 static int fetch_objs_via_rsync(struct transport *transport,
 264                                 int nr_objs, struct ref **to_fetch)
 265 {
 266         struct child_process rsync = CHILD_PROCESS_INIT;
 267
 268         rsync.stdout_to_stderr = 1;
 269         argv_array_push(&rsync.args, "rsync");
 270         argv_array_push(&rsync.args, (transport->verbose > 1) ? "-rv" : "-r");
 271         argv_array_push(&rsync.args, "--ignore-existing");
 272         argv_array_push(&rsync.args, "--exclude");
 273         argv_array_push(&rsync.args, "info");
 274         argv_array_pushf(&rsync.args, "%s/objects/", rsync_url(transport->url));
 275         argv_array_push(&rsync.args, get_object_directory());
 276
 277         /* NEEDSWORK: handle one level of alternates */
 278         return run_command(&rsync);
 279 }
 280
 281 static int write_one_ref(const char *name, const unsigned char *sha1,
 282                 int flags, void *data)
 283 {
 284         struct strbuf *buf = data;
 285         int len = buf->len;
 286         FILE *f;
 287
 288         /* when called via for_each_ref(), flags is non-zero */
 289         if (flags && !starts_with(name, "refs/heads/") &&
 290                         !starts_with(name, "refs/tags/"))
 291                 return 0;
 292
 293         strbuf_addstr(buf, name);
 294         if (safe_create_leading_directories(buf->buf) ||
 295                         !(f = fopen(buf->buf, "w")) ||
 296                         fprintf(f, "%s\n", sha1_to_hex(sha1)) < 0 ||
 297                         fclose(f))
 298                 return error("problems writing temporary file %s", buf->buf);
 299         strbuf_setlen(buf, len);
 300         return 0;
 301 }
 302
 303 static int write_refs_to_temp_dir(struct strbuf *temp_dir,
 304                 int refspec_nr, const char **refspec)
 305 {
 306         int i;
 307
 308         for (i = 0; i < refspec_nr; i++) {
 309                 unsigned char sha1[20];
 310                 char *ref;
 311
 312                 if (dwim_ref(refspec[i], strlen(refspec[i]), sha1, &ref) != 1)
 313                         return error("Could not get ref %s", refspec[i]);
 314
 315                 if (write_one_ref(ref, sha1, 0, temp_dir)) {
 316                         free(ref);
 317                         return -1;
 318                 }
 319                 free(ref);
 320         }
 321         return 0;
 322 }
 323
 324 static int rsync_transport_push(struct transport *transport,
 325                 int refspec_nr, const char **refspec, int flags)
 326 {
 327         struct strbuf buf = STRBUF_INIT, temp_dir = STRBUF_INIT;
 328         int result = 0, i;
 329         struct child_process rsync = CHILD_PROCESS_INIT;
 330         const char *args[10];
 331
 332         if (flags & TRANSPORT_PUSH_MIRROR)
 333                 return error("rsync transport does not support mirror mode");
 334
 335         /* first push the objects */
 336
 337         strbuf_addstr(&buf, rsync_url(transport->url));
 338         strbuf_addch(&buf, '/');
 339
 340         rsync.argv = args;
 341         rsync.stdout_to_stderr = 1;
 342         i = 0;
 343         args[i++] = "rsync";
 344         args[i++] = "-a";
 345         if (flags & TRANSPORT_PUSH_DRY_RUN)
 346                 args[i++] = "--dry-run";
 347         if (transport->verbose > 1)
 348                 args[i++] = "-v";
 349         args[i++] = "--ignore-existing";
 350         args[i++] = "--exclude";
 351         args[i++] = "info";
 352         args[i++] = get_object_directory();
 353         args[i++] = buf.buf;
 354         args[i++] = NULL;
 355
 356         if (run_command(&rsync))
 357                 return error("Could not push objects to %s",
 358                                 rsync_url(transport->url));
 359
 360         /* copy the refs to the temporary directory; they could be packed. */
 361
 362         strbuf_addstr(&temp_dir, git_path("rsync-refs-XXXXXX"));
 363         if (!mkdtemp(temp_dir.buf))
 364                 die_errno ("Could not make temporary directory");
 365         strbuf_addch(&temp_dir, '/');
 366
 367         if (flags & TRANSPORT_PUSH_ALL) {
 368                 if (for_each_ref(write_one_ref, &temp_dir))
 369                         return -1;
 370         } else if (write_refs_to_temp_dir(&temp_dir, refspec_nr, refspec))
 371                 return -1;
 372
 373         i = 2;
 374         if (flags & TRANSPORT_PUSH_DRY_RUN)
 375                 args[i++] = "--dry-run";
 376         if (!(flags & TRANSPORT_PUSH_FORCE))
 377                 args[i++] = "--ignore-existing";
 378         args[i++] = temp_dir.buf;
 379         args[i++] = rsync_url(transport->url);
 380         args[i++] = NULL;
 381         if (run_command(&rsync))
 382                 result = error("Could not push to %s",
 383                                 rsync_url(transport->url));
 384
 385         if (remove_dir_recursively(&temp_dir, 0))
 386                 warning ("Could not remove temporary directory %s.",
 387                                 temp_dir.buf);
 388
 389         strbuf_release(&buf);
 390         strbuf_release(&temp_dir);
 391
 392         return result;
 393 }
 394
 395 struct bundle_transport_data {
 396         int fd;
 397         struct bundle_header header;
 398 };
 399
 400 static struct ref *get_refs_from_bundle(struct transport *transport, int for_push)
 401 {
 402         struct bundle_transport_data *data = transport->data;
 403         struct ref *result = NULL;
 404         int i;
 405
 406         if (for_push)
 407                 return NULL;
 408
 409         if (data->fd > 0)
 410                 close(data->fd);
 411         data->fd = read_bundle_header(transport->url, &data->header);
 412         if (data->fd < 0)
 413                 die ("Could not read bundle '%s'.", transport->url);
 414         for (i = 0; i < data->header.references.nr; i++) {
 415                 struct ref_list_entry *e = data->header.references.list + i;
 416                 struct ref *ref = alloc_ref(e->name);
 417                 hashcpy(ref->old_sha1, e->sha1);
 418                 ref->next = result;
 419                 result = ref;
 420         }
 421         return result;
 422 }
 423
 424 static int fetch_refs_from_bundle(struct transport *transport,
 425                                int nr_heads, struct ref **to_fetch)
 426 {
 427         struct bundle_transport_data *data = transport->data;
 428         return unbundle(&data->header, data->fd,
 429                         transport->progress ? BUNDLE_VERBOSE : 0);
 430 }
 431
 432 static int close_bundle(struct transport *transport)
 433 {
 434         struct bundle_transport_data *data = transport->data;
 435         if (data->fd > 0)
 436                 close(data->fd);
 437         free(data);
 438         return 0;
 439 }
 440
 441 struct git_transport_data {
 442         struct git_transport_options options;
 443         struct child_process *conn;
 444         int fd[2];
 445         unsigned got_remote_heads : 1;
 446         struct sha1_array extra_have;
 447         struct sha1_array shallow;
 448 };
 449
 450 static int set_git_option(struct git_transport_options *opts,
 451                           const char *name, const char *value)
 452 {
 453         if (!strcmp(name, TRANS_OPT_UPLOADPACK)) {
 454                 opts->uploadpack = value;
 455                 return 0;
 456         } else if (!strcmp(name, TRANS_OPT_RECEIVEPACK)) {
 457                 opts->receivepack = value;
 458                 return 0;
 459         } else if (!strcmp(name, TRANS_OPT_THIN)) {
 460                 opts->thin = !!value;
 461                 return 0;
 462         } else if (!strcmp(name, TRANS_OPT_FOLLOWTAGS)) {
 463                 opts->followtags = !!value;
 464                 return 0;
 465         } else if (!strcmp(name, TRANS_OPT_KEEP)) {
 466                 opts->keep = !!value;
 467                 return 0;
 468         } else if (!strcmp(name, TRANS_OPT_UPDATE_SHALLOW)) {
 469                 opts->update_shallow = !!value;
 470                 return 0;
 471         } else if (!strcmp(name, TRANS_OPT_DEPTH)) {
 472                 if (!value)
 473                         opts->depth = 0;
 474                 else {
 475                         char *end;
 476                         opts->depth = strtol(value, &end, 0);
 477                         if (*end)
 478                                 die("transport: invalid depth option '%s'", value);
 479                 }
 480                 return 0;
 481         } else if (!strcmp(name, TRANS_OPT_PUSH_CERT)) {
 482                 opts->push_cert = !!value;
 483                 return 0;
 484         }
 485         return 1;
 486 }
 487
 488 static int connect_setup(struct transport *transport, int for_push, int verbose)
 489 {
 490         struct git_transport_data *data = transport->data;
 491
 492         if (data->conn)
 493                 return 0;
 494
 495         data->conn = git_connect(data->fd, transport->url,
 496                                  for_push ? data->options.receivepack :
 497                                  data->options.uploadpack,
 498                                  verbose ? CONNECT_VERBOSE : 0);
 499
 500         return 0;
 501 }
 502
 503 static struct ref *get_refs_via_connect(struct transport *transport, int for_push)
 504 {
 505         struct git_transport_data *data = transport->data;
 506         struct ref *refs;
 507
 508         connect_setup(transport, for_push, 0);
 509         get_remote_heads(data->fd[0], NULL, 0, &refs,
 510                          for_push ? REF_NORMAL : 0,
 511                          &data->extra_have,
 512                          &data->shallow);
 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         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         args.cloning = transport->cloning;
 540         args.update_shallow = data->options.update_shallow;
 541
 542         if (!data->got_remote_heads) {
 543                 connect_setup(transport, 0, 0);
 544                 get_remote_heads(data->fd[0], NULL, 0, &refs_tmp, 0,
 545                                  NULL, &data->shallow);
 546                 data->got_remote_heads = 1;
 547         }
 548
 549         refs = fetch_pack(&args, data->fd, data->conn,
 550                           refs_tmp ? refs_tmp : transport->remote_refs,
 551                           dest, to_fetch, nr_heads, &data->shallow,
 552                           &transport->pack_lockfile);
 553         close(data->fd[0]);
 554         close(data->fd[1]);
 555         if (finish_connect(data->conn)) {
 556                 free_refs(refs);
 557                 refs = NULL;
 558         }
 559         data->conn = NULL;
 560         data->got_remote_heads = 0;
 561         data->options.self_contained_and_connected =
 562                 args.self_contained_and_connected;
 563
 564         free_refs(refs_tmp);
 565         free_refs(refs);
 566         free(dest);
 567         return (refs ? 0 : -1);
 568 }
 569
 570 static int push_had_errors(struct ref *ref)
 571 {
 572         for (; ref; ref = ref->next) {
 573                 switch (ref->status) {
 574                 case REF_STATUS_NONE:
 575                 case REF_STATUS_UPTODATE:
 576                 case REF_STATUS_OK:
 577                         break;
 578                 default:
 579                         return 1;
 580                 }
 581         }
 582         return 0;
 583 }
 584
 585 int transport_refs_pushed(struct ref *ref)
 586 {
 587         for (; ref; ref = ref->next) {
 588                 switch(ref->status) {
 589                 case REF_STATUS_NONE:
 590                 case REF_STATUS_UPTODATE:
 591                         break;
 592                 default:
 593                         return 1;
 594                 }
 595         }
 596         return 0;
 597 }
 598
 599 void transport_update_tracking_ref(struct remote *remote, struct ref *ref, int verbose)
 600 {
 601         struct refspec rs;
 602
 603         if (ref->status != REF_STATUS_OK && ref->status != REF_STATUS_UPTODATE)
 604                 return;
 605
 606         rs.src = ref->name;
 607         rs.dst = NULL;
 608
 609         if (!remote_find_tracking(remote, &rs)) {
 610                 if (verbose)
 611                         fprintf(stderr, "updating local tracking ref '%s'\n", rs.dst);
 612                 if (ref->deletion) {
 613                         delete_ref(rs.dst, NULL, 0);
 614                 } else
 615                         update_ref("update by push", rs.dst,
 616                                         ref->new_sha1, NULL, 0, 0);
 617                 free(rs.dst);
 618         }
 619 }
 620
 621 static void print_ref_status(char flag, const char *summary, struct ref *to, struct ref *from, const char *msg, int porcelain)
 622 {
 623         if (porcelain) {
 624                 if (from)
 625                         fprintf(stdout, "%c\t%s:%s\t", flag, from->name, to->name);
 626                 else
 627                         fprintf(stdout, "%c\t:%s\t", flag, to->name);
 628                 if (msg)
 629                         fprintf(stdout, "%s (%s)\n", summary, msg);
 630                 else
 631                         fprintf(stdout, "%s\n", summary);
 632         } else {
 633                 fprintf(stderr, " %c %-*s ", flag, TRANSPORT_SUMMARY_WIDTH, summary);
 634                 if (from)
 635                         fprintf(stderr, "%s -> %s", prettify_refname(from->name), prettify_refname(to->name));
 636                 else
 637                         fputs(prettify_refname(to->name), stderr);
 638                 if (msg) {
 639                         fputs(" (", stderr);
 640                         fputs(msg, stderr);
 641                         fputc(')', stderr);
 642                 }
 643                 fputc('\n', stderr);
 644         }
 645 }
 646
 647 static const char *status_abbrev(unsigned char sha1[20])
 648 {
 649         return find_unique_abbrev(sha1, DEFAULT_ABBREV);
 650 }
 651
 652 static void print_ok_ref_status(struct ref *ref, int porcelain)
 653 {
 654         if (ref->deletion)
 655                 print_ref_status('-', "[deleted]", ref, NULL, NULL, porcelain);
 656         else if (is_null_sha1(ref->old_sha1))
 657                 print_ref_status('*',
 658                         (starts_with(ref->name, "refs/tags/") ? "[new tag]" :
 659                         "[new branch]"),
 660                         ref, ref->peer_ref, NULL, porcelain);
 661         else {
 662                 char quickref[84];
 663                 char type;
 664                 const char *msg;
 665
 666                 strcpy(quickref, status_abbrev(ref->old_sha1));
 667                 if (ref->forced_update) {
 668                         strcat(quickref, "...");
 669                         type = '+';
 670                         msg = "forced update";
 671                 } else {
 672                         strcat(quickref, "..");
 673                         type = ' ';
 674                         msg = NULL;
 675                 }
 676                 strcat(quickref, status_abbrev(ref->new_sha1));
 677
 678                 print_ref_status(type, quickref, ref, ref->peer_ref, msg, porcelain);
 679         }
 680 }
 681
 682 static int print_one_push_status(struct ref *ref, const char *dest, int count, int porcelain)
 683 {
 684         if (!count)
 685                 fprintf(porcelain ? stdout : stderr, "To %s\n", dest);
 686
 687         switch(ref->status) {
 688         case REF_STATUS_NONE:
 689                 print_ref_status('X', "[no match]", ref, NULL, NULL, porcelain);
 690                 break;
 691         case REF_STATUS_REJECT_NODELETE:
 692                 print_ref_status('!', "[rejected]", ref, NULL,
 693                                                  "remote does not support deleting refs", porcelain);
 694                 break;
 695         case REF_STATUS_UPTODATE:
 696                 print_ref_status('=', "[up to date]", ref,
 697                                                  ref->peer_ref, NULL, porcelain);
 698                 break;
 699         case REF_STATUS_REJECT_NONFASTFORWARD:
 700                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
 701                                                  "non-fast-forward", porcelain);
 702                 break;
 703         case REF_STATUS_REJECT_ALREADY_EXISTS:
 704                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
 705                                                  "already exists", porcelain);
 706                 break;
 707         case REF_STATUS_REJECT_FETCH_FIRST:
 708                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
 709                                                  "fetch first", porcelain);
 710                 break;
 711         case REF_STATUS_REJECT_NEEDS_FORCE:
 712                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
 713                                                  "needs force", porcelain);
 714                 break;
 715         case REF_STATUS_REJECT_STALE:
 716                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
 717                                                  "stale info", porcelain);
 718                 break;
 719         case REF_STATUS_REJECT_SHALLOW:
 720                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
 721                                                  "new shallow roots not allowed", porcelain);
 722                 break;
 723         case REF_STATUS_REMOTE_REJECT:
 724                 print_ref_status('!', "[remote rejected]", ref,
 725                                                  ref->deletion ? NULL : ref->peer_ref,
 726                                                  ref->remote_status, porcelain);
 727                 break;
 728         case REF_STATUS_EXPECTING_REPORT:
 729                 print_ref_status('!', "[remote failure]", ref,
 730                                                  ref->deletion ? NULL : ref->peer_ref,
 731                                                  "remote failed to report status", porcelain);
 732                 break;
 733         case REF_STATUS_OK:
 734                 print_ok_ref_status(ref, porcelain);
 735                 break;
 736         }
 737
 738         return 1;
 739 }
 740
 741 void transport_print_push_status(const char *dest, struct ref *refs,
 742                                   int verbose, int porcelain, unsigned int *reject_reasons)
 743 {
 744         struct ref *ref;
 745         int n = 0;
 746         unsigned char head_sha1[20];
 747         char *head;
 748
 749         head = resolve_refdup("HEAD", RESOLVE_REF_READING, head_sha1, NULL);
 750
 751         if (verbose) {
 752                 for (ref = refs; ref; ref = ref->next)
 753                         if (ref->status == REF_STATUS_UPTODATE)
 754                                 n += print_one_push_status(ref, dest, n, porcelain);
 755         }
 756
 757         for (ref = refs; ref; ref = ref->next)
 758                 if (ref->status == REF_STATUS_OK)
 759                         n += print_one_push_status(ref, dest, n, porcelain);
 760
 761         *reject_reasons = 0;
 762         for (ref = refs; ref; ref = ref->next) {
 763                 if (ref->status != REF_STATUS_NONE &&
 764                     ref->status != REF_STATUS_UPTODATE &&
 765                     ref->status != REF_STATUS_OK)
 766                         n += print_one_push_status(ref, dest, n, porcelain);
 767                 if (ref->status == REF_STATUS_REJECT_NONFASTFORWARD) {
 768                         if (head != NULL && !strcmp(head, ref->name))
 769                                 *reject_reasons |= REJECT_NON_FF_HEAD;
 770                         else
 771                                 *reject_reasons |= REJECT_NON_FF_OTHER;
 772                 } else if (ref->status == REF_STATUS_REJECT_ALREADY_EXISTS) {
 773                         *reject_reasons |= REJECT_ALREADY_EXISTS;
 774                 } else if (ref->status == REF_STATUS_REJECT_FETCH_FIRST) {
 775                         *reject_reasons |= REJECT_FETCH_FIRST;
 776                 } else if (ref->status == REF_STATUS_REJECT_NEEDS_FORCE) {
 777                         *reject_reasons |= REJECT_NEEDS_FORCE;
 778                 }
 779         }
 780         free(head);
 781 }
 782
 783 void transport_verify_remote_names(int nr_heads, const char **heads)
 784 {
 785         int i;
 786
 787         for (i = 0; i < nr_heads; i++) {
 788                 const char *local = heads[i];
 789                 const char *remote = strrchr(heads[i], ':');
 790
 791                 if (*local == '+')
 792                         local++;
 793
 794                 /* A matching refspec is okay.  */
 795                 if (remote == local && remote[1] == '\0')
 796                         continue;
 797
 798                 remote = remote ? (remote + 1) : local;
 799                 if (check_refname_format(remote,
 800                                 REFNAME_ALLOW_ONELEVEL|REFNAME_REFSPEC_PATTERN))
 801                         die("remote part of refspec is not a valid name in %s",
 802                                 heads[i]);
 803         }
 804 }
 805
 806 static int git_transport_push(struct transport *transport, struct ref *remote_refs, int flags)
 807 {
 808         struct git_transport_data *data = transport->data;
 809         struct send_pack_args args;
 810         int ret;
 811
 812         if (!data->got_remote_heads) {
 813                 struct ref *tmp_refs;
 814                 connect_setup(transport, 1, 0);
 815
 816                 get_remote_heads(data->fd[0], NULL, 0, &tmp_refs, REF_NORMAL,
 817                                  NULL, &data->shallow);
 818                 data->got_remote_heads = 1;
 819         }
 820
 821         memset(&args, 0, sizeof(args));
 822         args.send_mirror = !!(flags & TRANSPORT_PUSH_MIRROR);
 823         args.force_update = !!(flags & TRANSPORT_PUSH_FORCE);
 824         args.use_thin_pack = data->options.thin;
 825         args.verbose = (transport->verbose > 0);
 826         args.quiet = (transport->verbose < 0);
 827         args.progress = transport->progress;
 828         args.dry_run = !!(flags & TRANSPORT_PUSH_DRY_RUN);
 829         args.porcelain = !!(flags & TRANSPORT_PUSH_PORCELAIN);
 830         args.push_cert = !!(flags & TRANSPORT_PUSH_CERT);
 831         args.url = transport->url;
 832
 833         ret = send_pack(&args, data->fd, data->conn, remote_refs,
 834                         &data->extra_have);
 835
 836         close(data->fd[1]);
 837         close(data->fd[0]);
 838         ret |= finish_connect(data->conn);
 839         data->conn = NULL;
 840         data->got_remote_heads = 0;
 841
 842         return ret;
 843 }
 844
 845 static int connect_git(struct transport *transport, const char *name,
 846                        const char *executable, int fd[2])
 847 {
 848         struct git_transport_data *data = transport->data;
 849         data->conn = git_connect(data->fd, transport->url,
 850                                  executable, 0);
 851         fd[0] = data->fd[0];
 852         fd[1] = data->fd[1];
 853         return 0;
 854 }
 855
 856 static int disconnect_git(struct transport *transport)
 857 {
 858         struct git_transport_data *data = transport->data;
 859         if (data->conn) {
 860                 if (data->got_remote_heads)
 861                         packet_flush(data->fd[1]);
 862                 close(data->fd[0]);
 863                 close(data->fd[1]);
 864                 finish_connect(data->conn);
 865         }
 866
 867         free(data);
 868         return 0;
 869 }
 870
 871 void transport_take_over(struct transport *transport,
 872                          struct child_process *child)
 873 {
 874         struct git_transport_data *data;
 875
 876         if (!transport->smart_options)
 877                 die("Bug detected: Taking over transport requires non-NULL "
 878                     "smart_options field.");
 879
 880         data = xcalloc(1, sizeof(*data));
 881         data->options = *transport->smart_options;
 882         data->conn = child;
 883         data->fd[0] = data->conn->out;
 884         data->fd[1] = data->conn->in;
 885         data->got_remote_heads = 0;
 886         transport->data = data;
 887
 888         transport->set_option = NULL;
 889         transport->get_refs_list = get_refs_via_connect;
 890         transport->fetch = fetch_refs_via_pack;
 891         transport->push = NULL;
 892         transport->push_refs = git_transport_push;
 893         transport->disconnect = disconnect_git;
 894         transport->smart_options = &(data->options);
 895
 896         transport->cannot_reuse = 1;
 897 }
 898
 899 static int is_file(const char *url)
 900 {
 901         struct stat buf;
 902         if (stat(url, &buf))
 903                 return 0;
 904         return S_ISREG(buf.st_mode);
 905 }
 906
 907 static int external_specification_len(const char *url)
 908 {
 909         return strchr(url, ':') - url;
 910 }
 911
 912 struct transport *transport_get(struct remote *remote, const char *url)
 913 {
 914         const char *helper;
 915         struct transport *ret = xcalloc(1, sizeof(*ret));
 916
 917         ret->progress = isatty(2);
 918
 919         if (!remote)
 920                 die("No remote provided to transport_get()");
 921
 922         ret->got_remote_refs = 0;
 923         ret->remote = remote;
 924         helper = remote->foreign_vcs;
 925
 926         if (!url && remote->url)
 927                 url = remote->url[0];
 928         ret->url = url;
 929
 930         /* maybe it is a foreign URL? */
 931         if (url) {
 932                 const char *p = url;
 933
 934                 while (is_urlschemechar(p == url, *p))
 935                         p++;
 936                 if (starts_with(p, "::"))
 937                         helper = xstrndup(url, p - url);
 938         }
 939
 940         if (helper) {
 941                 transport_helper_init(ret, helper);
 942         } else if (starts_with(url, "rsync:")) {
 943                 ret->get_refs_list = get_refs_via_rsync;
 944                 ret->fetch = fetch_objs_via_rsync;
 945                 ret->push = rsync_transport_push;
 946                 ret->smart_options = NULL;
 947         } else if (url_is_local_not_ssh(url) && is_file(url) && is_bundle(url, 1)) {
 948                 struct bundle_transport_data *data = xcalloc(1, sizeof(*data));
 949                 ret->data = data;
 950                 ret->get_refs_list = get_refs_from_bundle;
 951                 ret->fetch = fetch_refs_from_bundle;
 952                 ret->disconnect = close_bundle;
 953                 ret->smart_options = NULL;
 954         } else if (!is_url(url)
 955                 || starts_with(url, "file://")
 956                 || starts_with(url, "git://")
 957                 || starts_with(url, "ssh://")
 958                 || starts_with(url, "git+ssh://")
 959                 || starts_with(url, "ssh+git://")) {
 960                 /* These are builtin smart transports. */
 961                 struct git_transport_data *data = xcalloc(1, sizeof(*data));
 962                 ret->data = data;
 963                 ret->set_option = NULL;
 964                 ret->get_refs_list = get_refs_via_connect;
 965                 ret->fetch = fetch_refs_via_pack;
 966                 ret->push_refs = git_transport_push;
 967                 ret->connect = connect_git;
 968                 ret->disconnect = disconnect_git;
 969                 ret->smart_options = &(data->options);
 970
 971                 data->conn = NULL;
 972                 data->got_remote_heads = 0;
 973         } else {
 974                 /* Unknown protocol in URL. Pass to external handler. */
 975                 int len = external_specification_len(url);
 976                 char *handler = xmemdupz(url, len);
 977                 transport_helper_init(ret, handler);
 978         }
 979
 980         if (ret->smart_options) {
 981                 ret->smart_options->thin = 1;
 982                 ret->smart_options->uploadpack = "git-upload-pack";
 983                 if (remote->uploadpack)
 984                         ret->smart_options->uploadpack = remote->uploadpack;
 985                 ret->smart_options->receivepack = "git-receive-pack";
 986                 if (remote->receivepack)
 987                         ret->smart_options->receivepack = remote->receivepack;
 988         }
 989
 990         return ret;
 991 }
 992
 993 int transport_set_option(struct transport *transport,
 994                          const char *name, const char *value)
 995 {
 996         int git_reports = 1, protocol_reports = 1;
 997
 998         if (transport->smart_options)
 999                 git_reports = set_git_option(transport->smart_options,
1000                                              name, value);
1001
1002         if (transport->set_option)
1003                 protocol_reports = transport->set_option(transport, name,
1004                                                         value);
1005
1006         /* If either report is 0, report 0 (success). */
1007         if (!git_reports || !protocol_reports)
1008                 return 0;
1009         /* If either reports -1 (invalid value), report -1. */
1010         if ((git_reports == -1) || (protocol_reports == -1))
1011                 return -1;
1012         /* Otherwise if both report unknown, report unknown. */
1013         return 1;
1014 }
1015
1016 void transport_set_verbosity(struct transport *transport, int verbosity,
1017         int force_progress)
1018 {
1019         if (verbosity >= 1)
1020                 transport->verbose = verbosity <= 3 ? verbosity : 3;
1021         if (verbosity < 0)
1022                 transport->verbose = -1;
1023
1024         /**
1025          * Rules used to determine whether to report progress (processing aborts
1026          * when a rule is satisfied):
1027          *
1028          *   . Report progress, if force_progress is 1 (ie. --progress).
1029          *   . Don't report progress, if force_progress is 0 (ie. --no-progress).
1030          *   . Don't report progress, if verbosity < 0 (ie. -q/--quiet ).
1031          *   . Report progress if isatty(2) is 1.
1032          **/
1033         if (force_progress >= 0)
1034                 transport->progress = !!force_progress;
1035         else
1036                 transport->progress = verbosity >= 0 && isatty(2);
1037 }
1038
1039 static void die_with_unpushed_submodules(struct string_list *needs_pushing)
1040 {
1041         int i;
1042
1043         fprintf(stderr, "The following submodule paths contain changes that can\n"
1044                         "not be found on any remote:\n");
1045         for (i = 0; i < needs_pushing->nr; i++)
1046                 printf("  %s\n", needs_pushing->items[i].string);
1047         fprintf(stderr, "\nPlease try\n\n"
1048                         "       git push --recurse-submodules=on-demand\n\n"
1049                         "or cd to the path and use\n\n"
1050                         "       git push\n\n"
1051                         "to push them to a remote.\n\n");
1052
1053         string_list_clear(needs_pushing, 0);
1054
1055         die("Aborting.");
1056 }
1057
1058 static int run_pre_push_hook(struct transport *transport,
1059                              struct ref *remote_refs)
1060 {
1061         int ret = 0, x;
1062         struct ref *r;
1063         struct child_process proc = CHILD_PROCESS_INIT;
1064         struct strbuf buf;
1065         const char *argv[4];
1066
1067         if (!(argv[0] = find_hook("pre-push")))
1068                 return 0;
1069
1070         argv[1] = transport->remote->name;
1071         argv[2] = transport->url;
1072         argv[3] = NULL;
1073
1074         proc.argv = argv;
1075         proc.in = -1;
1076
1077         if (start_command(&proc)) {
1078                 finish_command(&proc);
1079                 return -1;
1080         }
1081
1082         strbuf_init(&buf, 256);
1083
1084         for (r = remote_refs; r; r = r->next) {
1085                 if (!r->peer_ref) continue;
1086                 if (r->status == REF_STATUS_REJECT_NONFASTFORWARD) continue;
1087                 if (r->status == REF_STATUS_REJECT_STALE) continue;
1088                 if (r->status == REF_STATUS_UPTODATE) continue;
1089
1090                 strbuf_reset(&buf);
1091                 strbuf_addf( &buf, "%s %s %s %s\n",
1092                          r->peer_ref->name, sha1_to_hex(r->new_sha1),
1093                          r->name, sha1_to_hex(r->old_sha1));
1094
1095                 if (write_in_full(proc.in, buf.buf, buf.len) != buf.len) {
1096                         ret = -1;
1097                         break;
1098                 }
1099         }
1100
1101         strbuf_release(&buf);
1102
1103         x = close(proc.in);
1104         if (!ret)
1105                 ret = x;
1106
1107         x = finish_command(&proc);
1108         if (!ret)
1109                 ret = x;
1110
1111         return ret;
1112 }
1113
1114 int transport_push(struct transport *transport,
1115                    int refspec_nr, const char **refspec, int flags,
1116                    unsigned int *reject_reasons)
1117 {
1118         *reject_reasons = 0;
1119         transport_verify_remote_names(refspec_nr, refspec);
1120
1121         if (transport->push) {
1122                 /* Maybe FIXME. But no important transport uses this case. */
1123                 if (flags & TRANSPORT_PUSH_SET_UPSTREAM)
1124                         die("This transport does not support using --set-upstream");
1125
1126                 return transport->push(transport, refspec_nr, refspec, flags);
1127         } else if (transport->push_refs) {
1128                 struct ref *remote_refs;
1129                 struct ref *local_refs = get_local_heads();
1130                 int match_flags = MATCH_REFS_NONE;
1131                 int verbose = (transport->verbose > 0);
1132                 int quiet = (transport->verbose < 0);
1133                 int porcelain = flags & TRANSPORT_PUSH_PORCELAIN;
1134                 int pretend = flags & TRANSPORT_PUSH_DRY_RUN;
1135                 int push_ret, ret, err;
1136
1137                 if (check_push_refs(local_refs, refspec_nr, refspec) < 0)
1138                         return -1;
1139
1140                 remote_refs = transport->get_refs_list(transport, 1);
1141
1142                 if (flags & TRANSPORT_PUSH_ALL)
1143                         match_flags |= MATCH_REFS_ALL;
1144                 if (flags & TRANSPORT_PUSH_MIRROR)
1145                         match_flags |= MATCH_REFS_MIRROR;
1146                 if (flags & TRANSPORT_PUSH_PRUNE)
1147                         match_flags |= MATCH_REFS_PRUNE;
1148                 if (flags & TRANSPORT_PUSH_FOLLOW_TAGS)
1149                         match_flags |= MATCH_REFS_FOLLOW_TAGS;
1150
1151                 if (match_push_refs(local_refs, &remote_refs,
1152                                     refspec_nr, refspec, match_flags)) {
1153                         return -1;
1154                 }
1155
1156                 if (transport->smart_options &&
1157                     transport->smart_options->cas &&
1158                     !is_empty_cas(transport->smart_options->cas))
1159                         apply_push_cas(transport->smart_options->cas,
1160                                        transport->remote, remote_refs);
1161
1162                 set_ref_status_for_push(remote_refs,
1163                         flags & TRANSPORT_PUSH_MIRROR,
1164                         flags & TRANSPORT_PUSH_FORCE);
1165
1166                 if (!(flags & TRANSPORT_PUSH_NO_HOOK))
1167                         if (run_pre_push_hook(transport, remote_refs))
1168                                 return -1;
1169
1170                 if ((flags & TRANSPORT_RECURSE_SUBMODULES_ON_DEMAND) && !is_bare_repository()) {
1171                         struct ref *ref = remote_refs;
1172                         for (; ref; ref = ref->next)
1173                                 if (!is_null_sha1(ref->new_sha1) &&
1174                                     !push_unpushed_submodules(ref->new_sha1,
1175                                             transport->remote->name))
1176                                     die ("Failed to push all needed submodules!");
1177                 }
1178
1179                 if ((flags & (TRANSPORT_RECURSE_SUBMODULES_ON_DEMAND |
1180                               TRANSPORT_RECURSE_SUBMODULES_CHECK)) && !is_bare_repository()) {
1181                         struct ref *ref = remote_refs;
1182                         struct string_list needs_pushing = STRING_LIST_INIT_DUP;
1183
1184                         for (; ref; ref = ref->next)
1185                                 if (!is_null_sha1(ref->new_sha1) &&
1186                                     find_unpushed_submodules(ref->new_sha1,
1187                                             transport->remote->name, &needs_pushing))
1188                                         die_with_unpushed_submodules(&needs_pushing);
1189                 }
1190
1191                 push_ret = transport->push_refs(transport, remote_refs, flags);
1192                 err = push_had_errors(remote_refs);
1193                 ret = push_ret | err;
1194
1195                 if (!quiet || err)
1196                         transport_print_push_status(transport->url, remote_refs,
1197                                         verbose | porcelain, porcelain,
1198                                         reject_reasons);
1199
1200                 if (flags & TRANSPORT_PUSH_SET_UPSTREAM)
1201                         set_upstreams(transport, remote_refs, pretend);
1202
1203                 if (!(flags & TRANSPORT_PUSH_DRY_RUN)) {
1204                         struct ref *ref;
1205                         for (ref = remote_refs; ref; ref = ref->next)
1206                                 transport_update_tracking_ref(transport->remote, ref, verbose);
1207                 }
1208
1209                 if (porcelain && !push_ret)
1210                         puts("Done");
1211                 else if (!quiet && !ret && !transport_refs_pushed(remote_refs))
1212                         fprintf(stderr, "Everything up-to-date\n");
1213
1214                 return ret;
1215         }
1216         return 1;
1217 }
1218
1219 const struct ref *transport_get_remote_refs(struct transport *transport)
1220 {
1221         if (!transport->got_remote_refs) {
1222                 transport->remote_refs = transport->get_refs_list(transport, 0);
1223                 transport->got_remote_refs = 1;
1224         }
1225
1226         return transport->remote_refs;
1227 }
1228
1229 int transport_fetch_refs(struct transport *transport, struct ref *refs)
1230 {
1231         int rc;
1232         int nr_heads = 0, nr_alloc = 0, nr_refs = 0;
1233         struct ref **heads = NULL;
1234         struct ref *rm;
1235
1236         for (rm = refs; rm; rm = rm->next) {
1237                 nr_refs++;
1238                 if (rm->peer_ref &&
1239                     !is_null_sha1(rm->old_sha1) &&
1240                     !hashcmp(rm->peer_ref->old_sha1, rm->old_sha1))
1241                         continue;
1242                 ALLOC_GROW(heads, nr_heads + 1, nr_alloc);
1243                 heads[nr_heads++] = rm;
1244         }
1245
1246         if (!nr_heads) {
1247                 /*
1248                  * When deepening of a shallow repository is requested,
1249                  * then local and remote refs are likely to still be equal.
1250                  * Just feed them all to the fetch method in that case.
1251                  * This condition shouldn't be met in a non-deepening fetch
1252                  * (see builtin/fetch.c:quickfetch()).
1253                  */
1254                 heads = xmalloc(nr_refs * sizeof(*heads));
1255                 for (rm = refs; rm; rm = rm->next)
1256                         heads[nr_heads++] = rm;
1257         }
1258
1259         rc = transport->fetch(transport, nr_heads, heads);
1260
1261         free(heads);
1262         return rc;
1263 }
1264
1265 void transport_unlock_pack(struct transport *transport)
1266 {
1267         if (transport->pack_lockfile) {
1268                 unlink_or_warn(transport->pack_lockfile);
1269                 free(transport->pack_lockfile);
1270                 transport->pack_lockfile = NULL;
1271         }
1272 }
1273
1274 int transport_connect(struct transport *transport, const char *name,
1275                       const char *exec, int fd[2])
1276 {
1277         if (transport->connect)
1278                 return transport->connect(transport, name, exec, fd);
1279         else
1280                 die("Operation not supported by protocol");
1281 }
1282
1283 int transport_disconnect(struct transport *transport)
1284 {
1285         int ret = 0;
1286         if (transport->disconnect)
1287                 ret = transport->disconnect(transport);
1288         free(transport);
1289         return ret;
1290 }
1291
1292 /*
1293  * Strip username (and password) from a URL and return
1294  * it in a newly allocated string.
1295  */
1296 char *transport_anonymize_url(const char *url)
1297 {
1298         char *anon_url, *scheme_prefix, *anon_part;
1299         size_t anon_len, prefix_len = 0;
1300
1301         anon_part = strchr(url, '@');
1302         if (url_is_local_not_ssh(url) || !anon_part)
1303                 goto literal_copy;
1304
1305         anon_len = strlen(++anon_part);
1306         scheme_prefix = strstr(url, "://");
1307         if (!scheme_prefix) {
1308                 if (!strchr(anon_part, ':'))
1309                         /* cannot be "me@there:/path/name" */
1310                         goto literal_copy;
1311         } else {
1312                 const char *cp;
1313                 /* make sure scheme is reasonable */
1314                 for (cp = url; cp < scheme_prefix; cp++) {
1315                         switch (*cp) {
1316                                 /* RFC 1738 2.1 */
1317                         case '+': case '.': case '-':
1318                                 break; /* ok */
1319                         default:
1320                                 if (isalnum(*cp))
1321                                         break;
1322                                 /* it isn't */
1323                                 goto literal_copy;
1324                         }
1325                 }
1326                 /* @ past the first slash does not count */
1327                 cp = strchr(scheme_prefix + 3, '/');
1328                 if (cp && cp < anon_part)
1329                         goto literal_copy;
1330                 prefix_len = scheme_prefix - url + 3;
1331         }
1332         anon_url = xcalloc(1, 1 + prefix_len + anon_len);
1333         memcpy(anon_url, url, prefix_len);
1334         memcpy(anon_url + prefix_len, anon_part, anon_len);
1335         return anon_url;
1336 literal_copy:
1337         return xstrdup(url);
1338 }
1339
1340 struct alternate_refs_data {
1341         alternate_ref_fn *fn;
1342         void *data;
1343 };
1344
1345 static int refs_from_alternate_cb(struct alternate_object_database *e,
1346                                   void *data)
1347 {
1348         char *other;
1349         size_t len;
1350         struct remote *remote;
1351         struct transport *transport;
1352         const struct ref *extra;
1353         struct alternate_refs_data *cb = data;
1354
1355         e->name[-1] = '\0';
1356         other = xstrdup(real_path(e->base));
1357         e->name[-1] = '/';
1358         len = strlen(other);
1359
1360         while (other[len-1] == '/')
1361                 other[--len] = '\0';
1362         if (len < 8 || memcmp(other + len - 8, "/objects", 8))
1363                 goto out;
1364         /* Is this a git repository with refs? */
1365         memcpy(other + len - 8, "/refs", 6);
1366         if (!is_directory(other))
1367                 goto out;
1368         other[len - 8] = '\0';
1369         remote = remote_get(other);
1370         transport = transport_get(remote, other);
1371         for (extra = transport_get_remote_refs(transport);
1372              extra;
1373              extra = extra->next)
1374                 cb->fn(extra, cb->data);
1375         transport_disconnect(transport);
1376 out:
1377         free(other);
1378         return 0;
1379 }
1380
1381 void for_each_alternate_ref(alternate_ref_fn fn, void *data)
1382 {
1383         struct alternate_refs_data cb;
1384         cb.fn = fn;
1385         cb.data = data;
1386         foreach_alt_odb(refs_from_alternate_cb, &cb);
1387 }