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 "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
  18 /* rsync support */
  19
  20 /*
  21  * We copy packed-refs and refs/ into a temporary file, then read the
  22  * loose refs recursively (sorting whenever possible), and then inserting
  23  * those packed refs that are not yet in the list (not validating, but
  24  * assuming that the file is sorted).
  25  *
  26  * Appears refactoring this from refs.c is too cumbersome.
  27  */
  28
  29 static int str_cmp(const void *a, const void *b)
  30 {
  31         const char *s1 = a;
  32         const char *s2 = b;
  33
  34         return strcmp(s1, s2);
  35 }
  36
  37 /* path->buf + name_offset is expected to point to "refs/" */
  38
  39 static int read_loose_refs(struct strbuf *path, int name_offset,
  40                 struct ref **tail)
  41 {
  42         DIR *dir = opendir(path->buf);
  43         struct dirent *de;
  44         struct {
  45                 char **entries;
  46                 int nr, alloc;
  47         } list;
  48         int i, pathlen;
  49
  50         if (!dir)
  51                 return -1;
  52
  53         memset (&list, 0, sizeof(list));
  54
  55         while ((de = readdir(dir))) {
  56                 if (is_dot_or_dotdot(de->d_name))
  57                         continue;
  58                 ALLOC_GROW(list.entries, list.nr + 1, list.alloc);
  59                 list.entries[list.nr++] = xstrdup(de->d_name);
  60         }
  61         closedir(dir);
  62
  63         /* sort the list */
  64
  65         qsort(list.entries, list.nr, sizeof(char *), str_cmp);
  66
  67         pathlen = path->len;
  68         strbuf_addch(path, '/');
  69
  70         for (i = 0; i < list.nr; i++, strbuf_setlen(path, pathlen + 1)) {
  71                 strbuf_addstr(path, list.entries[i]);
  72                 if (read_loose_refs(path, name_offset, tail)) {
  73                         int fd = open(path->buf, O_RDONLY);
  74                         char buffer[40];
  75                         struct ref *next;
  76
  77                         if (fd < 0)
  78                                 continue;
  79                         next = alloc_ref(path->buf + name_offset);
  80                         if (read_in_full(fd, buffer, 40) != 40 ||
  81                                         get_sha1_hex(buffer, next->old_sha1)) {
  82                                 close(fd);
  83                                 free(next);
  84                                 continue;
  85                         }
  86                         close(fd);
  87                         (*tail)->next = next;
  88                         *tail = next;
  89                 }
  90         }
  91         strbuf_setlen(path, pathlen);
  92
  93         for (i = 0; i < list.nr; i++)
  94                 free(list.entries[i]);
  95         free(list.entries);
  96
  97         return 0;
  98 }
  99
 100 /* insert the packed refs for which no loose refs were found */
 101
 102 static void insert_packed_refs(const char *packed_refs, struct ref **list)
 103 {
 104         FILE *f = fopen(packed_refs, "r");
 105         static char buffer[PATH_MAX];
 106
 107         if (!f)
 108                 return;
 109
 110         for (;;) {
 111                 int cmp = 0; /* assigned before used */
 112                 int len;
 113
 114                 if (!fgets(buffer, sizeof(buffer), f)) {
 115                         fclose(f);
 116                         return;
 117                 }
 118
 119                 if (hexval(buffer[0]) > 0xf)
 120                         continue;
 121                 len = strlen(buffer);
 122                 if (len && buffer[len - 1] == '\n')
 123                         buffer[--len] = '\0';
 124                 if (len < 41)
 125                         continue;
 126                 while ((*list)->next &&
 127                                 (cmp = strcmp(buffer + 41,
 128                                       (*list)->next->name)) > 0)
 129                         list = &(*list)->next;
 130                 if (!(*list)->next || cmp < 0) {
 131                         struct ref *next = alloc_ref(buffer + 41);
 132                         buffer[40] = '\0';
 133                         if (get_sha1_hex(buffer, next->old_sha1)) {
 134                                 warning ("invalid SHA-1: %s", buffer);
 135                                 free(next);
 136                                 continue;
 137                         }
 138                         next->next = (*list)->next;
 139                         (*list)->next = next;
 140                         list = &(*list)->next;
 141                 }
 142         }
 143 }
 144
 145 static void set_upstreams(struct transport *transport, struct ref *refs,
 146         int pretend)
 147 {
 148         struct ref *ref;
 149         for (ref = refs; ref; ref = ref->next) {
 150                 const char *localname;
 151                 const char *tmp;
 152                 const char *remotename;
 153                 unsigned char sha[20];
 154                 int flag = 0;
 155                 /*
 156                  * Check suitability for tracking. Must be successful /
 157                  * already up-to-date ref create/modify (not delete).
 158                  */
 159                 if (ref->status != REF_STATUS_OK &&
 160                         ref->status != REF_STATUS_UPTODATE)
 161                         continue;
 162                 if (!ref->peer_ref)
 163                         continue;
 164                 if (is_null_sha1(ref->new_sha1))
 165                         continue;
 166
 167                 /* Follow symbolic refs (mainly for HEAD). */
 168                 localname = ref->peer_ref->name;
 169                 remotename = ref->name;
 170                 tmp = resolve_ref_unsafe(localname, sha, 1, &flag);
 171                 if (tmp && flag & REF_ISSYMREF &&
 172                         !prefixcmp(tmp, "refs/heads/"))
 173                         localname = tmp;
 174
 175                 /* Both source and destination must be local branches. */
 176                 if (!localname || prefixcmp(localname, "refs/heads/"))
 177                         continue;
 178                 if (!remotename || prefixcmp(remotename, "refs/heads/"))
 179                         continue;
 180
 181                 if (!pretend)
 182                         install_branch_config(BRANCH_CONFIG_VERBOSE,
 183                                 localname + 11, transport->remote->name,
 184                                 remotename);
 185                 else
 186                         printf("Would set upstream of '%s' to '%s' of '%s'\n",
 187                                 localname + 11, remotename + 11,
 188                                 transport->remote->name);
 189         }
 190 }
 191
 192 static const char *rsync_url(const char *url)
 193 {
 194         return prefixcmp(url, "rsync://") ? skip_prefix(url, "rsync:") : url;
 195 }
 196
 197 static struct ref *get_refs_via_rsync(struct transport *transport, int for_push)
 198 {
 199         struct strbuf buf = STRBUF_INIT, temp_dir = STRBUF_INIT;
 200         struct ref dummy = {NULL}, *tail = &dummy;
 201         struct child_process rsync;
 202         const char *args[5];
 203         int temp_dir_len;
 204
 205         if (for_push)
 206                 return NULL;
 207
 208         /* copy the refs to the temporary directory */
 209
 210         strbuf_addstr(&temp_dir, git_path("rsync-refs-XXXXXX"));
 211         if (!mkdtemp(temp_dir.buf))
 212                 die_errno ("Could not make temporary directory");
 213         temp_dir_len = temp_dir.len;
 214
 215         strbuf_addstr(&buf, rsync_url(transport->url));
 216         strbuf_addstr(&buf, "/refs");
 217
 218         memset(&rsync, 0, sizeof(rsync));
 219         rsync.argv = args;
 220         rsync.stdout_to_stderr = 1;
 221         args[0] = "rsync";
 222         args[1] = (transport->verbose > 1) ? "-rv" : "-r";
 223         args[2] = buf.buf;
 224         args[3] = temp_dir.buf;
 225         args[4] = NULL;
 226
 227         if (run_command(&rsync))
 228                 die ("Could not run rsync to get refs");
 229
 230         strbuf_reset(&buf);
 231         strbuf_addstr(&buf, rsync_url(transport->url));
 232         strbuf_addstr(&buf, "/packed-refs");
 233
 234         args[2] = buf.buf;
 235
 236         if (run_command(&rsync))
 237                 die ("Could not run rsync to get refs");
 238
 239         /* read the copied refs */
 240
 241         strbuf_addstr(&temp_dir, "/refs");
 242         read_loose_refs(&temp_dir, temp_dir_len + 1, &tail);
 243         strbuf_setlen(&temp_dir, temp_dir_len);
 244
 245         tail = &dummy;
 246         strbuf_addstr(&temp_dir, "/packed-refs");
 247         insert_packed_refs(temp_dir.buf, &tail);
 248         strbuf_setlen(&temp_dir, temp_dir_len);
 249
 250         if (remove_dir_recursively(&temp_dir, 0))
 251                 warning ("Error removing temporary directory %s.",
 252                                 temp_dir.buf);
 253
 254         strbuf_release(&buf);
 255         strbuf_release(&temp_dir);
 256
 257         return dummy.next;
 258 }
 259
 260 static int fetch_objs_via_rsync(struct transport *transport,
 261                                 int nr_objs, struct ref **to_fetch)
 262 {
 263         struct strbuf buf = STRBUF_INIT;
 264         struct child_process rsync;
 265         const char *args[8];
 266         int result;
 267
 268         strbuf_addstr(&buf, rsync_url(transport->url));
 269         strbuf_addstr(&buf, "/objects/");
 270
 271         memset(&rsync, 0, sizeof(rsync));
 272         rsync.argv = args;
 273         rsync.stdout_to_stderr = 1;
 274         args[0] = "rsync";
 275         args[1] = (transport->verbose > 1) ? "-rv" : "-r";
 276         args[2] = "--ignore-existing";
 277         args[3] = "--exclude";
 278         args[4] = "info";
 279         args[5] = buf.buf;
 280         args[6] = get_object_directory();
 281         args[7] = NULL;
 282
 283         /* NEEDSWORK: handle one level of alternates */
 284         result = run_command(&rsync);
 285
 286         strbuf_release(&buf);
 287
 288         return result;
 289 }
 290
 291 static int write_one_ref(const char *name, const unsigned char *sha1,
 292                 int flags, void *data)
 293 {
 294         struct strbuf *buf = data;
 295         int len = buf->len;
 296         FILE *f;
 297
 298         /* when called via for_each_ref(), flags is non-zero */
 299         if (flags && prefixcmp(name, "refs/heads/") &&
 300                         prefixcmp(name, "refs/tags/"))
 301                 return 0;
 302
 303         strbuf_addstr(buf, name);
 304         if (safe_create_leading_directories(buf->buf) ||
 305                         !(f = fopen(buf->buf, "w")) ||
 306                         fprintf(f, "%s\n", sha1_to_hex(sha1)) < 0 ||
 307                         fclose(f))
 308                 return error("problems writing temporary file %s", buf->buf);
 309         strbuf_setlen(buf, len);
 310         return 0;
 311 }
 312
 313 static int write_refs_to_temp_dir(struct strbuf *temp_dir,
 314                 int refspec_nr, const char **refspec)
 315 {
 316         int i;
 317
 318         for (i = 0; i < refspec_nr; i++) {
 319                 unsigned char sha1[20];
 320                 char *ref;
 321
 322                 if (dwim_ref(refspec[i], strlen(refspec[i]), sha1, &ref) != 1)
 323                         return error("Could not get ref %s", refspec[i]);
 324
 325                 if (write_one_ref(ref, sha1, 0, temp_dir)) {
 326                         free(ref);
 327                         return -1;
 328                 }
 329                 free(ref);
 330         }
 331         return 0;
 332 }
 333
 334 static int rsync_transport_push(struct transport *transport,
 335                 int refspec_nr, const char **refspec, int flags)
 336 {
 337         struct strbuf buf = STRBUF_INIT, temp_dir = STRBUF_INIT;
 338         int result = 0, i;
 339         struct child_process rsync;
 340         const char *args[10];
 341
 342         if (flags & TRANSPORT_PUSH_MIRROR)
 343                 return error("rsync transport does not support mirror mode");
 344
 345         /* first push the objects */
 346
 347         strbuf_addstr(&buf, rsync_url(transport->url));
 348         strbuf_addch(&buf, '/');
 349
 350         memset(&rsync, 0, sizeof(rsync));
 351         rsync.argv = args;
 352         rsync.stdout_to_stderr = 1;
 353         i = 0;
 354         args[i++] = "rsync";
 355         args[i++] = "-a";
 356         if (flags & TRANSPORT_PUSH_DRY_RUN)
 357                 args[i++] = "--dry-run";
 358         if (transport->verbose > 1)
 359                 args[i++] = "-v";
 360         args[i++] = "--ignore-existing";
 361         args[i++] = "--exclude";
 362         args[i++] = "info";
 363         args[i++] = get_object_directory();
 364         args[i++] = buf.buf;
 365         args[i++] = NULL;
 366
 367         if (run_command(&rsync))
 368                 return error("Could not push objects to %s",
 369                                 rsync_url(transport->url));
 370
 371         /* copy the refs to the temporary directory; they could be packed. */
 372
 373         strbuf_addstr(&temp_dir, git_path("rsync-refs-XXXXXX"));
 374         if (!mkdtemp(temp_dir.buf))
 375                 die_errno ("Could not make temporary directory");
 376         strbuf_addch(&temp_dir, '/');
 377
 378         if (flags & TRANSPORT_PUSH_ALL) {
 379                 if (for_each_ref(write_one_ref, &temp_dir))
 380                         return -1;
 381         } else if (write_refs_to_temp_dir(&temp_dir, refspec_nr, refspec))
 382                 return -1;
 383
 384         i = 2;
 385         if (flags & TRANSPORT_PUSH_DRY_RUN)
 386                 args[i++] = "--dry-run";
 387         if (!(flags & TRANSPORT_PUSH_FORCE))
 388                 args[i++] = "--ignore-existing";
 389         args[i++] = temp_dir.buf;
 390         args[i++] = rsync_url(transport->url);
 391         args[i++] = NULL;
 392         if (run_command(&rsync))
 393                 result = error("Could not push to %s",
 394                                 rsync_url(transport->url));
 395
 396         if (remove_dir_recursively(&temp_dir, 0))
 397                 warning ("Could not remove temporary directory %s.",
 398                                 temp_dir.buf);
 399
 400         strbuf_release(&buf);
 401         strbuf_release(&temp_dir);
 402
 403         return result;
 404 }
 405
 406 struct bundle_transport_data {
 407         int fd;
 408         struct bundle_header header;
 409 };
 410
 411 static struct ref *get_refs_from_bundle(struct transport *transport, int for_push)
 412 {
 413         struct bundle_transport_data *data = transport->data;
 414         struct ref *result = NULL;
 415         int i;
 416
 417         if (for_push)
 418                 return NULL;
 419
 420         if (data->fd > 0)
 421                 close(data->fd);
 422         data->fd = read_bundle_header(transport->url, &data->header);
 423         if (data->fd < 0)
 424                 die ("Could not read bundle '%s'.", transport->url);
 425         for (i = 0; i < data->header.references.nr; i++) {
 426                 struct ref_list_entry *e = data->header.references.list + i;
 427                 struct ref *ref = alloc_ref(e->name);
 428                 hashcpy(ref->old_sha1, e->sha1);
 429                 ref->next = result;
 430                 result = ref;
 431         }
 432         return result;
 433 }
 434
 435 static int fetch_refs_from_bundle(struct transport *transport,
 436                                int nr_heads, struct ref **to_fetch)
 437 {
 438         struct bundle_transport_data *data = transport->data;
 439         return unbundle(&data->header, data->fd,
 440                         transport->progress ? BUNDLE_VERBOSE : 0);
 441 }
 442
 443 static int close_bundle(struct transport *transport)
 444 {
 445         struct bundle_transport_data *data = transport->data;
 446         if (data->fd > 0)
 447                 close(data->fd);
 448         free(data);
 449         return 0;
 450 }
 451
 452 struct git_transport_data {
 453         struct git_transport_options options;
 454         struct child_process *conn;
 455         int fd[2];
 456         unsigned got_remote_heads : 1;
 457         struct extra_have_objects extra_have;
 458 };
 459
 460 static int set_git_option(struct git_transport_options *opts,
 461                           const char *name, const char *value)
 462 {
 463         if (!strcmp(name, TRANS_OPT_UPLOADPACK)) {
 464                 opts->uploadpack = value;
 465                 return 0;
 466         } else if (!strcmp(name, TRANS_OPT_RECEIVEPACK)) {
 467                 opts->receivepack = value;
 468                 return 0;
 469         } else if (!strcmp(name, TRANS_OPT_THIN)) {
 470                 opts->thin = !!value;
 471                 return 0;
 472         } else if (!strcmp(name, TRANS_OPT_FOLLOWTAGS)) {
 473                 opts->followtags = !!value;
 474                 return 0;
 475         } else if (!strcmp(name, TRANS_OPT_KEEP)) {
 476                 opts->keep = !!value;
 477                 return 0;
 478         } else if (!strcmp(name, TRANS_OPT_DEPTH)) {
 479                 if (!value)
 480                         opts->depth = 0;
 481                 else {
 482                         char *end;
 483                         opts->depth = strtol(value, &end, 0);
 484                         if (*end)
 485                                 die("transport: invalid depth option '%s'", value);
 486                 }
 487                 return 0;
 488         }
 489         return 1;
 490 }
 491
 492 static int connect_setup(struct transport *transport, int for_push, int verbose)
 493 {
 494         struct git_transport_data *data = transport->data;
 495
 496         if (data->conn)
 497                 return 0;
 498
 499         data->conn = git_connect(data->fd, transport->url,
 500                                  for_push ? data->options.receivepack :
 501                                  data->options.uploadpack,
 502                                  verbose ? CONNECT_VERBOSE : 0);
 503
 504         return 0;
 505 }
 506
 507 static struct ref *get_refs_via_connect(struct transport *transport, int for_push)
 508 {
 509         struct git_transport_data *data = transport->data;
 510         struct ref *refs;
 511
 512         connect_setup(transport, for_push, 0);
 513         get_remote_heads(data->fd[0], NULL, 0, &refs,
 514                          for_push ? REF_NORMAL : 0, &data->extra_have);
 515         data->got_remote_heads = 1;
 516
 517         return refs;
 518 }
 519
 520 static int fetch_refs_via_pack(struct transport *transport,
 521                                int nr_heads, struct ref **to_fetch)
 522 {
 523         struct git_transport_data *data = transport->data;
 524         const struct ref *refs;
 525         char *dest = xstrdup(transport->url);
 526         struct fetch_pack_args args;
 527         struct ref *refs_tmp = NULL;
 528
 529         memset(&args, 0, sizeof(args));
 530         args.uploadpack = data->options.uploadpack;
 531         args.keep_pack = data->options.keep;
 532         args.lock_pack = 1;
 533         args.use_thin_pack = data->options.thin;
 534         args.include_tag = data->options.followtags;
 535         args.verbose = (transport->verbose > 1);
 536         args.quiet = (transport->verbose < 0);
 537         args.no_progress = !transport->progress;
 538         args.depth = data->options.depth;
 539         args.check_self_contained_and_connected =
 540                 data->options.check_self_contained_and_connected;
 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, NULL);
 545                 data->got_remote_heads = 1;
 546         }
 547
 548         refs = fetch_pack(&args, data->fd, data->conn,
 549                           refs_tmp ? refs_tmp : transport->remote_refs,
 550                           dest, to_fetch, nr_heads,
 551                           &transport->pack_lockfile);
 552         close(data->fd[0]);
 553         close(data->fd[1]);
 554         if (finish_connect(data->conn))
 555                 refs = NULL;
 556         data->conn = NULL;
 557         data->got_remote_heads = 0;
 558         data->options.self_contained_and_connected =
 559                 args.self_contained_and_connected;
 560
 561         free_refs(refs_tmp);
 562
 563         free(dest);
 564         return (refs ? 0 : -1);
 565 }
 566
 567 static int push_had_errors(struct ref *ref)
 568 {
 569         for (; ref; ref = ref->next) {
 570                 switch (ref->status) {
 571                 case REF_STATUS_NONE:
 572                 case REF_STATUS_UPTODATE:
 573                 case REF_STATUS_OK:
 574                         break;
 575                 default:
 576                         return 1;
 577                 }
 578         }
 579         return 0;
 580 }
 581
 582 int transport_refs_pushed(struct ref *ref)
 583 {
 584         for (; ref; ref = ref->next) {
 585                 switch(ref->status) {
 586                 case REF_STATUS_NONE:
 587                 case REF_STATUS_UPTODATE:
 588                         break;
 589                 default:
 590                         return 1;
 591                 }
 592         }
 593         return 0;
 594 }
 595
 596 void transport_update_tracking_ref(struct remote *remote, struct ref *ref, int verbose)
 597 {
 598         struct refspec rs;
 599
 600         if (ref->status != REF_STATUS_OK && ref->status != REF_STATUS_UPTODATE)
 601                 return;
 602
 603         rs.src = ref->name;
 604         rs.dst = NULL;
 605
 606         if (!remote_find_tracking(remote, &rs)) {
 607                 if (verbose)
 608                         fprintf(stderr, "updating local tracking ref '%s'\n", rs.dst);
 609                 if (ref->deletion) {
 610                         delete_ref(rs.dst, NULL, 0);
 611                 } else
 612                         update_ref("update by push", rs.dst,
 613                                         ref->new_sha1, NULL, 0, 0);
 614                 free(rs.dst);
 615         }
 616 }
 617
 618 static void print_ref_status(char flag, const char *summary, struct ref *to, struct ref *from, const char *msg, int porcelain)
 619 {
 620         if (porcelain) {
 621                 if (from)
 622                         fprintf(stdout, "%c\t%s:%s\t", flag, from->name, to->name);
 623                 else
 624                         fprintf(stdout, "%c\t:%s\t", flag, to->name);
 625                 if (msg)
 626                         fprintf(stdout, "%s (%s)\n", summary, msg);
 627                 else
 628                         fprintf(stdout, "%s\n", summary);
 629         } else {
 630                 fprintf(stderr, " %c %-*s ", flag, TRANSPORT_SUMMARY_WIDTH, summary);
 631                 if (from)
 632                         fprintf(stderr, "%s -> %s", prettify_refname(from->name), prettify_refname(to->name));
 633                 else
 634                         fputs(prettify_refname(to->name), stderr);
 635                 if (msg) {
 636                         fputs(" (", stderr);
 637                         fputs(msg, stderr);
 638                         fputc(')', stderr);
 639                 }
 640                 fputc('\n', stderr);
 641         }
 642 }
 643
 644 static const char *status_abbrev(unsigned char sha1[20])
 645 {
 646         return find_unique_abbrev(sha1, DEFAULT_ABBREV);
 647 }
 648
 649 static void print_ok_ref_status(struct ref *ref, int porcelain)
 650 {
 651         if (ref->deletion)
 652                 print_ref_status('-', "[deleted]", ref, NULL, NULL, porcelain);
 653         else if (is_null_sha1(ref->old_sha1))
 654                 print_ref_status('*',
 655                         (!prefixcmp(ref->name, "refs/tags/") ? "[new tag]" :
 656                         "[new branch]"),
 657                         ref, ref->peer_ref, NULL, porcelain);
 658         else {
 659                 char quickref[84];
 660                 char type;
 661                 const char *msg;
 662
 663                 strcpy(quickref, status_abbrev(ref->old_sha1));
 664                 if (ref->forced_update) {
 665                         strcat(quickref, "...");
 666                         type = '+';
 667                         msg = "forced update";
 668                 } else {
 669                         strcat(quickref, "..");
 670                         type = ' ';
 671                         msg = NULL;
 672                 }
 673                 strcat(quickref, status_abbrev(ref->new_sha1));
 674
 675                 print_ref_status(type, quickref, ref, ref->peer_ref, msg, porcelain);
 676         }
 677 }
 678
 679 static int print_one_push_status(struct ref *ref, const char *dest, int count, int porcelain)
 680 {
 681         if (!count)
 682                 fprintf(porcelain ? stdout : stderr, "To %s\n", dest);
 683
 684         switch(ref->status) {
 685         case REF_STATUS_NONE:
 686                 print_ref_status('X', "[no match]", ref, NULL, NULL, porcelain);
 687                 break;
 688         case REF_STATUS_REJECT_NODELETE:
 689                 print_ref_status('!', "[rejected]", ref, NULL,
 690                                                  "remote does not support deleting refs", porcelain);
 691                 break;
 692         case REF_STATUS_UPTODATE:
 693                 print_ref_status('=', "[up to date]", ref,
 694                                                  ref->peer_ref, NULL, porcelain);
 695                 break;
 696         case REF_STATUS_REJECT_NONFASTFORWARD:
 697                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
 698                                                  "non-fast-forward", porcelain);
 699                 break;
 700         case REF_STATUS_REJECT_ALREADY_EXISTS:
 701                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
 702                                                  "already exists", porcelain);
 703                 break;
 704         case REF_STATUS_REJECT_FETCH_FIRST:
 705                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
 706                                                  "fetch first", porcelain);
 707                 break;
 708         case REF_STATUS_REJECT_NEEDS_FORCE:
 709                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
 710                                                  "needs force", porcelain);
 711                 break;
 712         case REF_STATUS_REJECT_STALE:
 713                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
 714                                                  "stale info", porcelain);
 715                 break;
 716         case REF_STATUS_REMOTE_REJECT:
 717                 print_ref_status('!', "[remote rejected]", ref,
 718                                                  ref->deletion ? NULL : ref->peer_ref,
 719                                                  ref->remote_status, porcelain);
 720                 break;
 721         case REF_STATUS_EXPECTING_REPORT:
 722                 print_ref_status('!', "[remote failure]", ref,
 723                                                  ref->deletion ? NULL : ref->peer_ref,
 724                                                  "remote failed to report status", porcelain);
 725                 break;
 726         case REF_STATUS_OK:
 727                 print_ok_ref_status(ref, porcelain);
 728                 break;
 729         }
 730
 731         return 1;
 732 }
 733
 734 void transport_print_push_status(const char *dest, struct ref *refs,
 735                                   int verbose, int porcelain, unsigned int *reject_reasons)
 736 {
 737         struct ref *ref;
 738         int n = 0;
 739         unsigned char head_sha1[20];
 740         char *head;
 741
 742         head = resolve_refdup("HEAD", head_sha1, 1, NULL);
 743
 744         if (verbose) {
 745                 for (ref = refs; ref; ref = ref->next)
 746                         if (ref->status == REF_STATUS_UPTODATE)
 747                                 n += print_one_push_status(ref, dest, n, porcelain);
 748         }
 749
 750         for (ref = refs; ref; ref = ref->next)
 751                 if (ref->status == REF_STATUS_OK)
 752                         n += print_one_push_status(ref, dest, n, porcelain);
 753
 754         *reject_reasons = 0;
 755         for (ref = refs; ref; ref = ref->next) {
 756                 if (ref->status != REF_STATUS_NONE &&
 757                     ref->status != REF_STATUS_UPTODATE &&
 758                     ref->status != REF_STATUS_OK)
 759                         n += print_one_push_status(ref, dest, n, porcelain);
 760                 if (ref->status == REF_STATUS_REJECT_NONFASTFORWARD) {
 761                         if (head != NULL && !strcmp(head, ref->name))
 762                                 *reject_reasons |= REJECT_NON_FF_HEAD;
 763                         else
 764                                 *reject_reasons |= REJECT_NON_FF_OTHER;
 765                 } else if (ref->status == REF_STATUS_REJECT_ALREADY_EXISTS) {
 766                         *reject_reasons |= REJECT_ALREADY_EXISTS;
 767                 } else if (ref->status == REF_STATUS_REJECT_FETCH_FIRST) {
 768                         *reject_reasons |= REJECT_FETCH_FIRST;
 769                 } else if (ref->status == REF_STATUS_REJECT_NEEDS_FORCE) {
 770                         *reject_reasons |= REJECT_NEEDS_FORCE;
 771                 }
 772         }
 773 }
 774
 775 void transport_verify_remote_names(int nr_heads, const char **heads)
 776 {
 777         int i;
 778
 779         for (i = 0; i < nr_heads; i++) {
 780                 const char *local = heads[i];
 781                 const char *remote = strrchr(heads[i], ':');
 782
 783                 if (*local == '+')
 784                         local++;
 785
 786                 /* A matching refspec is okay.  */
 787                 if (remote == local && remote[1] == '\0')
 788                         continue;
 789
 790                 remote = remote ? (remote + 1) : local;
 791                 if (check_refname_format(remote,
 792                                 REFNAME_ALLOW_ONELEVEL|REFNAME_REFSPEC_PATTERN))
 793                         die("remote part of refspec is not a valid name in %s",
 794                                 heads[i]);
 795         }
 796 }
 797
 798 static int git_transport_push(struct transport *transport, struct ref *remote_refs, int flags)
 799 {
 800         struct git_transport_data *data = transport->data;
 801         struct send_pack_args args;
 802         int ret;
 803
 804         if (!data->got_remote_heads) {
 805                 struct ref *tmp_refs;
 806                 connect_setup(transport, 1, 0);
 807
 808                 get_remote_heads(data->fd[0], NULL, 0, &tmp_refs, REF_NORMAL, NULL);
 809                 data->got_remote_heads = 1;
 810         }
 811
 812         memset(&args, 0, sizeof(args));
 813         args.send_mirror = !!(flags & TRANSPORT_PUSH_MIRROR);
 814         args.force_update = !!(flags & TRANSPORT_PUSH_FORCE);
 815         args.use_thin_pack = data->options.thin;
 816         args.verbose = (transport->verbose > 0);
 817         args.quiet = (transport->verbose < 0);
 818         args.progress = transport->progress;
 819         args.dry_run = !!(flags & TRANSPORT_PUSH_DRY_RUN);
 820         args.porcelain = !!(flags & TRANSPORT_PUSH_PORCELAIN);
 821
 822         ret = send_pack(&args, data->fd, data->conn, remote_refs,
 823                         &data->extra_have);
 824
 825         close(data->fd[1]);
 826         close(data->fd[0]);
 827         ret |= finish_connect(data->conn);
 828         data->conn = NULL;
 829         data->got_remote_heads = 0;
 830
 831         return ret;
 832 }
 833
 834 static int connect_git(struct transport *transport, const char *name,
 835                        const char *executable, int fd[2])
 836 {
 837         struct git_transport_data *data = transport->data;
 838         data->conn = git_connect(data->fd, transport->url,
 839                                  executable, 0);
 840         fd[0] = data->fd[0];
 841         fd[1] = data->fd[1];
 842         return 0;
 843 }
 844
 845 static int disconnect_git(struct transport *transport)
 846 {
 847         struct git_transport_data *data = transport->data;
 848         if (data->conn) {
 849                 if (data->got_remote_heads)
 850                         packet_flush(data->fd[1]);
 851                 close(data->fd[0]);
 852                 close(data->fd[1]);
 853                 finish_connect(data->conn);
 854         }
 855
 856         free(data);
 857         return 0;
 858 }
 859
 860 void transport_take_over(struct transport *transport,
 861                          struct child_process *child)
 862 {
 863         struct git_transport_data *data;
 864
 865         if (!transport->smart_options)
 866                 die("Bug detected: Taking over transport requires non-NULL "
 867                     "smart_options field.");
 868
 869         data = xcalloc(1, sizeof(*data));
 870         data->options = *transport->smart_options;
 871         data->conn = child;
 872         data->fd[0] = data->conn->out;
 873         data->fd[1] = data->conn->in;
 874         data->got_remote_heads = 0;
 875         transport->data = data;
 876
 877         transport->set_option = NULL;
 878         transport->get_refs_list = get_refs_via_connect;
 879         transport->fetch = fetch_refs_via_pack;
 880         transport->push = NULL;
 881         transport->push_refs = git_transport_push;
 882         transport->disconnect = disconnect_git;
 883         transport->smart_options = &(data->options);
 884
 885         transport->cannot_reuse = 1;
 886 }
 887
 888 static int is_local(const char *url)
 889 {
 890         const char *colon = strchr(url, ':');
 891         const char *slash = strchr(url, '/');
 892         return !colon || (slash && slash < colon) ||
 893                 has_dos_drive_prefix(url);
 894 }
 895
 896 static int is_file(const char *url)
 897 {
 898         struct stat buf;
 899         if (stat(url, &buf))
 900                 return 0;
 901         return S_ISREG(buf.st_mode);
 902 }
 903
 904 static int external_specification_len(const char *url)
 905 {
 906         return strchr(url, ':') - url;
 907 }
 908
 909 struct transport *transport_get(struct remote *remote, const char *url)
 910 {
 911         const char *helper;
 912         struct transport *ret = xcalloc(1, sizeof(*ret));
 913
 914         ret->progress = isatty(2);
 915
 916         if (!remote)
 917                 die("No remote provided to transport_get()");
 918
 919         ret->got_remote_refs = 0;
 920         ret->remote = remote;
 921         helper = remote->foreign_vcs;
 922
 923         if (!url && remote->url)
 924                 url = remote->url[0];
 925         ret->url = url;
 926
 927         /* maybe it is a foreign URL? */
 928         if (url) {
 929                 const char *p = url;
 930
 931                 while (is_urlschemechar(p == url, *p))
 932                         p++;
 933                 if (!prefixcmp(p, "::"))
 934                         helper = xstrndup(url, p - url);
 935         }
 936
 937         if (helper) {
 938                 transport_helper_init(ret, helper);
 939         } else if (!prefixcmp(url, "rsync:")) {
 940                 ret->get_refs_list = get_refs_via_rsync;
 941                 ret->fetch = fetch_objs_via_rsync;
 942                 ret->push = rsync_transport_push;
 943                 ret->smart_options = NULL;
 944         } else if (is_local(url) && is_file(url) && is_bundle(url, 1)) {
 945                 struct bundle_transport_data *data = xcalloc(1, sizeof(*data));
 946                 ret->data = data;
 947                 ret->get_refs_list = get_refs_from_bundle;
 948                 ret->fetch = fetch_refs_from_bundle;
 949                 ret->disconnect = close_bundle;
 950                 ret->smart_options = NULL;
 951         } else if (!is_url(url)
 952                 || !prefixcmp(url, "file://")
 953                 || !prefixcmp(url, "git://")
 954                 || !prefixcmp(url, "ssh://")
 955                 || !prefixcmp(url, "git+ssh://")
 956                 || !prefixcmp(url, "ssh+git://")) {
 957                 /* These are builtin smart transports. */
 958                 struct git_transport_data *data = xcalloc(1, sizeof(*data));
 959                 ret->data = data;
 960                 ret->set_option = NULL;
 961                 ret->get_refs_list = get_refs_via_connect;
 962                 ret->fetch = fetch_refs_via_pack;
 963                 ret->push_refs = git_transport_push;
 964                 ret->connect = connect_git;
 965                 ret->disconnect = disconnect_git;
 966                 ret->smart_options = &(data->options);
 967
 968                 data->conn = NULL;
 969                 data->got_remote_heads = 0;
 970         } else {
 971                 /* Unknown protocol in URL. Pass to external handler. */
 972                 int len = external_specification_len(url);
 973                 char *handler = xmalloc(len + 1);
 974                 handler[len] = 0;
 975                 strncpy(handler, url, len);
 976                 transport_helper_init(ret, handler);
 977         }
 978
 979         if (ret->smart_options) {
 980                 ret->smart_options->thin = 1;
 981                 ret->smart_options->uploadpack = "git-upload-pack";
 982                 if (remote->uploadpack)
 983                         ret->smart_options->uploadpack = remote->uploadpack;
 984                 ret->smart_options->receivepack = "git-receive-pack";
 985                 if (remote->receivepack)
 986                         ret->smart_options->receivepack = remote->receivepack;
 987         }
 988
 989         return ret;
 990 }
 991
 992 int transport_set_option(struct transport *transport,
 993                          const char *name, const char *value)
 994 {
 995         int git_reports = 1, protocol_reports = 1;
 996
 997         if (transport->smart_options)
 998                 git_reports = set_git_option(transport->smart_options,
 999                                              name, value);
1000
1001         if (transport->set_option)
1002                 protocol_reports = transport->set_option(transport, name,
1003                                                         value);
1004
1005         /* If either report is 0, report 0 (success). */
1006         if (!git_reports || !protocol_reports)
1007                 return 0;
1008         /* If either reports -1 (invalid value), report -1. */
1009         if ((git_reports == -1) || (protocol_reports == -1))
1010                 return -1;
1011         /* Otherwise if both report unknown, report unknown. */
1012         return 1;
1013 }
1014
1015 void transport_set_verbosity(struct transport *transport, int verbosity,
1016         int force_progress)
1017 {
1018         if (verbosity >= 1)
1019                 transport->verbose = verbosity <= 3 ? verbosity : 3;
1020         if (verbosity < 0)
1021                 transport->verbose = -1;
1022
1023         /**
1024          * Rules used to determine whether to report progress (processing aborts
1025          * when a rule is satisfied):
1026          *
1027          *   . Report progress, if force_progress is 1 (ie. --progress).
1028          *   . Don't report progress, if force_progress is 0 (ie. --no-progress).
1029          *   . Don't report progress, if verbosity < 0 (ie. -q/--quiet ).
1030          *   . Report progress if isatty(2) is 1.
1031          **/
1032         if (force_progress >= 0)
1033                 transport->progress = !!force_progress;
1034         else
1035                 transport->progress = verbosity >= 0 && isatty(2);
1036 }
1037
1038 static void die_with_unpushed_submodules(struct string_list *needs_pushing)
1039 {
1040         int i;
1041
1042         fprintf(stderr, "The following submodule paths contain changes that can\n"
1043                         "not be found on any remote:\n");
1044         for (i = 0; i < needs_pushing->nr; i++)
1045                 printf("  %s\n", needs_pushing->items[i].string);
1046         fprintf(stderr, "\nPlease try\n\n"
1047                         "       git push --recurse-submodules=on-demand\n\n"
1048                         "or cd to the path and use\n\n"
1049                         "       git push\n\n"
1050                         "to push them to a remote.\n\n");
1051
1052         string_list_clear(needs_pushing, 0);
1053
1054         die("Aborting.");
1055 }
1056
1057 static int run_pre_push_hook(struct transport *transport,
1058                              struct ref *remote_refs)
1059 {
1060         int ret = 0, x;
1061         struct ref *r;
1062         struct child_process proc;
1063         struct strbuf buf;
1064         const char *argv[4];
1065
1066         if (!(argv[0] = find_hook("pre-push")))
1067                 return 0;
1068
1069         argv[1] = transport->remote->name;
1070         argv[2] = transport->url;
1071         argv[3] = NULL;
1072
1073         memset(&proc, 0, sizeof(proc));
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                         transport->get_refs_list(transport, 1);
1130                 struct ref *local_refs = get_local_heads();
1131                 int match_flags = MATCH_REFS_NONE;
1132                 int verbose = (transport->verbose > 0);
1133                 int quiet = (transport->verbose < 0);
1134                 int porcelain = flags & TRANSPORT_PUSH_PORCELAIN;
1135                 int pretend = flags & TRANSPORT_PUSH_DRY_RUN;
1136                 int push_ret, ret, err;
1137
1138                 if (flags & TRANSPORT_PUSH_ALL)
1139                         match_flags |= MATCH_REFS_ALL;
1140                 if (flags & TRANSPORT_PUSH_MIRROR)
1141                         match_flags |= MATCH_REFS_MIRROR;
1142                 if (flags & TRANSPORT_PUSH_PRUNE)
1143                         match_flags |= MATCH_REFS_PRUNE;
1144                 if (flags & TRANSPORT_PUSH_FOLLOW_TAGS)
1145                         match_flags |= MATCH_REFS_FOLLOW_TAGS;
1146
1147                 if (match_push_refs(local_refs, &remote_refs,
1148                                     refspec_nr, refspec, match_flags)) {
1149                         return -1;
1150                 }
1151
1152                 if (transport->smart_options &&
1153                     transport->smart_options->cas &&
1154                     !is_empty_cas(transport->smart_options->cas))
1155                         apply_push_cas(transport->smart_options->cas,
1156                                        transport->remote, remote_refs);
1157
1158                 set_ref_status_for_push(remote_refs,
1159                         flags & TRANSPORT_PUSH_MIRROR,
1160                         flags & TRANSPORT_PUSH_FORCE);
1161
1162                 if (!(flags & TRANSPORT_PUSH_NO_HOOK))
1163                         if (run_pre_push_hook(transport, remote_refs))
1164                                 return -1;
1165
1166                 if ((flags & TRANSPORT_RECURSE_SUBMODULES_ON_DEMAND) && !is_bare_repository()) {
1167                         struct ref *ref = remote_refs;
1168                         for (; ref; ref = ref->next)
1169                                 if (!is_null_sha1(ref->new_sha1) &&
1170                                     !push_unpushed_submodules(ref->new_sha1,
1171                                             transport->remote->name))
1172                                     die ("Failed to push all needed submodules!");
1173                 }
1174
1175                 if ((flags & (TRANSPORT_RECURSE_SUBMODULES_ON_DEMAND |
1176                               TRANSPORT_RECURSE_SUBMODULES_CHECK)) && !is_bare_repository()) {
1177                         struct ref *ref = remote_refs;
1178                         struct string_list needs_pushing;
1179
1180                         memset(&needs_pushing, 0, sizeof(struct string_list));
1181                         needs_pushing.strdup_strings = 1;
1182                         for (; ref; ref = ref->next)
1183                                 if (!is_null_sha1(ref->new_sha1) &&
1184                                     find_unpushed_submodules(ref->new_sha1,
1185                                             transport->remote->name, &needs_pushing))
1186                                         die_with_unpushed_submodules(&needs_pushing);
1187                 }
1188
1189                 push_ret = transport->push_refs(transport, remote_refs, flags);
1190                 err = push_had_errors(remote_refs);
1191                 ret = push_ret | err;
1192
1193                 if (!quiet || err)
1194                         transport_print_push_status(transport->url, remote_refs,
1195                                         verbose | porcelain, porcelain,
1196                                         reject_reasons);
1197
1198                 if (flags & TRANSPORT_PUSH_SET_UPSTREAM)
1199                         set_upstreams(transport, remote_refs, pretend);
1200
1201                 if (!(flags & TRANSPORT_PUSH_DRY_RUN)) {
1202                         struct ref *ref;
1203                         for (ref = remote_refs; ref; ref = ref->next)
1204                                 transport_update_tracking_ref(transport->remote, ref, verbose);
1205                 }
1206
1207                 if (porcelain && !push_ret)
1208                         puts("Done");
1209                 else if (!quiet && !ret && !transport_refs_pushed(remote_refs))
1210                         fprintf(stderr, "Everything up-to-date\n");
1211
1212                 return ret;
1213         }
1214         return 1;
1215 }
1216
1217 const struct ref *transport_get_remote_refs(struct transport *transport)
1218 {
1219         if (!transport->got_remote_refs) {
1220                 transport->remote_refs = transport->get_refs_list(transport, 0);
1221                 transport->got_remote_refs = 1;
1222         }
1223
1224         return transport->remote_refs;
1225 }
1226
1227 int transport_fetch_refs(struct transport *transport, struct ref *refs)
1228 {
1229         int rc;
1230         int nr_heads = 0, nr_alloc = 0, nr_refs = 0;
1231         struct ref **heads = NULL;
1232         struct ref *rm;
1233
1234         for (rm = refs; rm; rm = rm->next) {
1235                 nr_refs++;
1236                 if (rm->peer_ref &&
1237                     !is_null_sha1(rm->old_sha1) &&
1238                     !hashcmp(rm->peer_ref->old_sha1, rm->old_sha1))
1239                         continue;
1240                 ALLOC_GROW(heads, nr_heads + 1, nr_alloc);
1241                 heads[nr_heads++] = rm;
1242         }
1243
1244         if (!nr_heads) {
1245                 /*
1246                  * When deepening of a shallow repository is requested,
1247                  * then local and remote refs are likely to still be equal.
1248                  * Just feed them all to the fetch method in that case.
1249                  * This condition shouldn't be met in a non-deepening fetch
1250                  * (see builtin/fetch.c:quickfetch()).
1251                  */
1252                 heads = xmalloc(nr_refs * sizeof(*heads));
1253                 for (rm = refs; rm; rm = rm->next)
1254                         heads[nr_heads++] = rm;
1255         }
1256
1257         rc = transport->fetch(transport, nr_heads, heads);
1258
1259         free(heads);
1260         return rc;
1261 }
1262
1263 void transport_unlock_pack(struct transport *transport)
1264 {
1265         if (transport->pack_lockfile) {
1266                 unlink_or_warn(transport->pack_lockfile);
1267                 free(transport->pack_lockfile);
1268                 transport->pack_lockfile = NULL;
1269         }
1270 }
1271
1272 int transport_connect(struct transport *transport, const char *name,
1273                       const char *exec, int fd[2])
1274 {
1275         if (transport->connect)
1276                 return transport->connect(transport, name, exec, fd);
1277         else
1278                 die("Operation not supported by protocol");
1279 }
1280
1281 int transport_disconnect(struct transport *transport)
1282 {
1283         int ret = 0;
1284         if (transport->disconnect)
1285                 ret = transport->disconnect(transport);
1286         free(transport);
1287         return ret;
1288 }
1289
1290 /*
1291  * Strip username (and password) from a URL and return
1292  * it in a newly allocated string.
1293  */
1294 char *transport_anonymize_url(const char *url)
1295 {
1296         char *anon_url, *scheme_prefix, *anon_part;
1297         size_t anon_len, prefix_len = 0;
1298
1299         anon_part = strchr(url, '@');
1300         if (is_local(url) || !anon_part)
1301                 goto literal_copy;
1302
1303         anon_len = strlen(++anon_part);
1304         scheme_prefix = strstr(url, "://");
1305         if (!scheme_prefix) {
1306                 if (!strchr(anon_part, ':'))
1307                         /* cannot be "me@there:/path/name" */
1308                         goto literal_copy;
1309         } else {
1310                 const char *cp;
1311                 /* make sure scheme is reasonable */
1312                 for (cp = url; cp < scheme_prefix; cp++) {
1313                         switch (*cp) {
1314                                 /* RFC 1738 2.1 */
1315                         case '+': case '.': case '-':
1316                                 break; /* ok */
1317                         default:
1318                                 if (isalnum(*cp))
1319                                         break;
1320                                 /* it isn't */
1321                                 goto literal_copy;
1322                         }
1323                 }
1324                 /* @ past the first slash does not count */
1325                 cp = strchr(scheme_prefix + 3, '/');
1326                 if (cp && cp < anon_part)
1327                         goto literal_copy;
1328                 prefix_len = scheme_prefix - url + 3;
1329         }
1330         anon_url = xcalloc(1, 1 + prefix_len + anon_len);
1331         memcpy(anon_url, url, prefix_len);
1332         memcpy(anon_url + prefix_len, anon_part, anon_len);
1333         return anon_url;
1334 literal_copy:
1335         return xstrdup(url);
1336 }
1337
1338 struct alternate_refs_data {
1339         alternate_ref_fn *fn;
1340         void *data;
1341 };
1342
1343 static int refs_from_alternate_cb(struct alternate_object_database *e,
1344                                   void *data)
1345 {
1346         char *other;
1347         size_t len;
1348         struct remote *remote;
1349         struct transport *transport;
1350         const struct ref *extra;
1351         struct alternate_refs_data *cb = data;
1352
1353         e->name[-1] = '\0';
1354         other = xstrdup(real_path(e->base));
1355         e->name[-1] = '/';
1356         len = strlen(other);
1357
1358         while (other[len-1] == '/')
1359                 other[--len] = '\0';
1360         if (len < 8 || memcmp(other + len - 8, "/objects", 8))
1361                 return 0;
1362         /* Is this a git repository with refs? */
1363         memcpy(other + len - 8, "/refs", 6);
1364         if (!is_directory(other))
1365                 return 0;
1366         other[len - 8] = '\0';
1367         remote = remote_get(other);
1368         transport = transport_get(remote, other);
1369         for (extra = transport_get_remote_refs(transport);
1370              extra;
1371              extra = extra->next)
1372                 cb->fn(extra, cb->data);
1373         transport_disconnect(transport);
1374         free(other);
1375         return 0;
1376 }
1377
1378 void for_each_alternate_ref(alternate_ref_fn fn, void *data)
1379 {
1380         struct alternate_refs_data cb;
1381         cb.fn = fn;
1382         cb.data = data;
1383         foreach_alt_odb(refs_from_alternate_cb, &cb);
1384 }