transport.c

   1 #include "cache.h"
   2 #include "transport.h"
   3 #include "run-command.h"
   4 #ifndef NO_CURL
   5 #include "http.h"
   6 #endif
   7 #include "pkt-line.h"
   8 #include "fetch-pack.h"
   9 #include "send-pack.h"
  10 #include "walker.h"
  11 #include "bundle.h"
  12 #include "dir.h"
  13 #include "refs.h"
  14
  15 /* rsync support */
  16
  17 /*
  18  * We copy packed-refs and refs/ into a temporary file, then read the
  19  * loose refs recursively (sorting whenever possible), and then inserting
  20  * those packed refs that are not yet in the list (not validating, but
  21  * assuming that the file is sorted).
  22  *
  23  * Appears refactoring this from refs.c is too cumbersome.
  24  */
  25
  26 static int str_cmp(const void *a, const void *b)
  27 {
  28         const char *s1 = a;
  29         const char *s2 = b;
  30
  31         return strcmp(s1, s2);
  32 }
  33
  34 /* path->buf + name_offset is expected to point to "refs/" */
  35
  36 static int read_loose_refs(struct strbuf *path, int name_offset,
  37                 struct ref **tail)
  38 {
  39         DIR *dir = opendir(path->buf);
  40         struct dirent *de;
  41         struct {
  42                 char **entries;
  43                 int nr, alloc;
  44         } list;
  45         int i, pathlen;
  46
  47         if (!dir)
  48                 return -1;
  49
  50         memset (&list, 0, sizeof(list));
  51
  52         while ((de = readdir(dir))) {
  53                 if (de->d_name[0] == '.' && (de->d_name[1] == '\0' ||
  54                                 (de->d_name[1] == '.' &&
  55                                  de->d_name[2] == '\0')))
  56                         continue;
  57                 ALLOC_GROW(list.entries, list.nr + 1, list.alloc);
  58                 list.entries[list.nr++] = xstrdup(de->d_name);
  59         }
  60         closedir(dir);
  61
  62         /* sort the list */
  63
  64         qsort(list.entries, list.nr, sizeof(char *), str_cmp);
  65
  66         pathlen = path->len;
  67         strbuf_addch(path, '/');
  68
  69         for (i = 0; i < list.nr; i++, strbuf_setlen(path, pathlen + 1)) {
  70                 strbuf_addstr(path, list.entries[i]);
  71                 if (read_loose_refs(path, name_offset, tail)) {
  72                         int fd = open(path->buf, O_RDONLY);
  73                         char buffer[40];
  74                         struct ref *next;
  75
  76                         if (fd < 0)
  77                                 continue;
  78                         next = alloc_ref(path->len - name_offset + 1);
  79                         if (read_in_full(fd, buffer, 40) != 40 ||
  80                                         get_sha1_hex(buffer, next->old_sha1)) {
  81                                 close(fd);
  82                                 free(next);
  83                                 continue;
  84                         }
  85                         close(fd);
  86                         strcpy(next->name, path->buf + name_offset);
  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 = cmp, len;
 112
 113                 if (!fgets(buffer, sizeof(buffer), f)) {
 114                         fclose(f);
 115                         return;
 116                 }
 117
 118                 if (hexval(buffer[0]) > 0xf)
 119                         continue;
 120                 len = strlen(buffer);
 121                 if (buffer[len - 1] == '\n')
 122                         buffer[--len] = '\0';
 123                 if (len < 41)
 124                         continue;
 125                 while ((*list)->next &&
 126                                 (cmp = strcmp(buffer + 41,
 127                                       (*list)->next->name)) > 0)
 128                         list = &(*list)->next;
 129                 if (!(*list)->next || cmp < 0) {
 130                         struct ref *next = alloc_ref(len - 40);
 131                         buffer[40] = '\0';
 132                         if (get_sha1_hex(buffer, next->old_sha1)) {
 133                                 warning ("invalid SHA-1: %s", buffer);
 134                                 free(next);
 135                                 continue;
 136                         }
 137                         strcpy(next->name, buffer + 41);
 138                         next->next = (*list)->next;
 139                         (*list)->next = next;
 140                         list = &(*list)->next;
 141                 }
 142         }
 143 }
 144
 145 static struct ref *get_refs_via_rsync(struct transport *transport)
 146 {
 147         struct strbuf buf = STRBUF_INIT, temp_dir = STRBUF_INIT;
 148         struct ref dummy, *tail = &dummy;
 149         struct child_process rsync;
 150         const char *args[5];
 151         int temp_dir_len;
 152
 153         /* copy the refs to the temporary directory */
 154
 155         strbuf_addstr(&temp_dir, git_path("rsync-refs-XXXXXX"));
 156         if (!mkdtemp(temp_dir.buf))
 157                 die ("Could not make temporary directory");
 158         temp_dir_len = temp_dir.len;
 159
 160         strbuf_addstr(&buf, transport->url);
 161         strbuf_addstr(&buf, "/refs");
 162
 163         memset(&rsync, 0, sizeof(rsync));
 164         rsync.argv = args;
 165         rsync.stdout_to_stderr = 1;
 166         args[0] = "rsync";
 167         args[1] = (transport->verbose > 0) ? "-rv" : "-r";
 168         args[2] = buf.buf;
 169         args[3] = temp_dir.buf;
 170         args[4] = NULL;
 171
 172         if (run_command(&rsync))
 173                 die ("Could not run rsync to get refs");
 174
 175         strbuf_reset(&buf);
 176         strbuf_addstr(&buf, transport->url);
 177         strbuf_addstr(&buf, "/packed-refs");
 178
 179         args[2] = buf.buf;
 180
 181         if (run_command(&rsync))
 182                 die ("Could not run rsync to get refs");
 183
 184         /* read the copied refs */
 185
 186         strbuf_addstr(&temp_dir, "/refs");
 187         read_loose_refs(&temp_dir, temp_dir_len + 1, &tail);
 188         strbuf_setlen(&temp_dir, temp_dir_len);
 189
 190         tail = &dummy;
 191         strbuf_addstr(&temp_dir, "/packed-refs");
 192         insert_packed_refs(temp_dir.buf, &tail);
 193         strbuf_setlen(&temp_dir, temp_dir_len);
 194
 195         if (remove_dir_recursively(&temp_dir, 0))
 196                 warning ("Error removing temporary directory %s.",
 197                                 temp_dir.buf);
 198
 199         strbuf_release(&buf);
 200         strbuf_release(&temp_dir);
 201
 202         return dummy.next;
 203 }
 204
 205 static int fetch_objs_via_rsync(struct transport *transport,
 206                                  int nr_objs, struct ref **to_fetch)
 207 {
 208         struct strbuf buf = STRBUF_INIT;
 209         struct child_process rsync;
 210         const char *args[8];
 211         int result;
 212
 213         strbuf_addstr(&buf, transport->url);
 214         strbuf_addstr(&buf, "/objects/");
 215
 216         memset(&rsync, 0, sizeof(rsync));
 217         rsync.argv = args;
 218         rsync.stdout_to_stderr = 1;
 219         args[0] = "rsync";
 220         args[1] = (transport->verbose > 0) ? "-rv" : "-r";
 221         args[2] = "--ignore-existing";
 222         args[3] = "--exclude";
 223         args[4] = "info";
 224         args[5] = buf.buf;
 225         args[6] = get_object_directory();
 226         args[7] = NULL;
 227
 228         /* NEEDSWORK: handle one level of alternates */
 229         result = run_command(&rsync);
 230
 231         strbuf_release(&buf);
 232
 233         return result;
 234 }
 235
 236 static int write_one_ref(const char *name, const unsigned char *sha1,
 237                 int flags, void *data)
 238 {
 239         struct strbuf *buf = data;
 240         int len = buf->len;
 241         FILE *f;
 242
 243         /* when called via for_each_ref(), flags is non-zero */
 244         if (flags && prefixcmp(name, "refs/heads/") &&
 245                         prefixcmp(name, "refs/tags/"))
 246                 return 0;
 247
 248         strbuf_addstr(buf, name);
 249         if (safe_create_leading_directories(buf->buf) ||
 250                         !(f = fopen(buf->buf, "w")) ||
 251                         fprintf(f, "%s\n", sha1_to_hex(sha1)) < 0 ||
 252                         fclose(f))
 253                 return error("problems writing temporary file %s", buf->buf);
 254         strbuf_setlen(buf, len);
 255         return 0;
 256 }
 257
 258 static int write_refs_to_temp_dir(struct strbuf *temp_dir,
 259                 int refspec_nr, const char **refspec)
 260 {
 261         int i;
 262
 263         for (i = 0; i < refspec_nr; i++) {
 264                 unsigned char sha1[20];
 265                 char *ref;
 266
 267                 if (dwim_ref(refspec[i], strlen(refspec[i]), sha1, &ref) != 1)
 268                         return error("Could not get ref %s", refspec[i]);
 269
 270                 if (write_one_ref(ref, sha1, 0, temp_dir)) {
 271                         free(ref);
 272                         return -1;
 273                 }
 274                 free(ref);
 275         }
 276         return 0;
 277 }
 278
 279 static int rsync_transport_push(struct transport *transport,
 280                 int refspec_nr, const char **refspec, int flags)
 281 {
 282         struct strbuf buf = STRBUF_INIT, temp_dir = STRBUF_INIT;
 283         int result = 0, i;
 284         struct child_process rsync;
 285         const char *args[10];
 286
 287         if (flags & TRANSPORT_PUSH_MIRROR)
 288                 return error("rsync transport does not support mirror mode");
 289
 290         /* first push the objects */
 291
 292         strbuf_addstr(&buf, transport->url);
 293         strbuf_addch(&buf, '/');
 294
 295         memset(&rsync, 0, sizeof(rsync));
 296         rsync.argv = args;
 297         rsync.stdout_to_stderr = 1;
 298         i = 0;
 299         args[i++] = "rsync";
 300         args[i++] = "-a";
 301         if (flags & TRANSPORT_PUSH_DRY_RUN)
 302                 args[i++] = "--dry-run";
 303         if (transport->verbose > 0)
 304                 args[i++] = "-v";
 305         args[i++] = "--ignore-existing";
 306         args[i++] = "--exclude";
 307         args[i++] = "info";
 308         args[i++] = get_object_directory();
 309         args[i++] = buf.buf;
 310         args[i++] = NULL;
 311
 312         if (run_command(&rsync))
 313                 return error("Could not push objects to %s", transport->url);
 314
 315         /* copy the refs to the temporary directory; they could be packed. */
 316
 317         strbuf_addstr(&temp_dir, git_path("rsync-refs-XXXXXX"));
 318         if (!mkdtemp(temp_dir.buf))
 319                 die ("Could not make temporary directory");
 320         strbuf_addch(&temp_dir, '/');
 321
 322         if (flags & TRANSPORT_PUSH_ALL) {
 323                 if (for_each_ref(write_one_ref, &temp_dir))
 324                         return -1;
 325         } else if (write_refs_to_temp_dir(&temp_dir, refspec_nr, refspec))
 326                 return -1;
 327
 328         i = 2;
 329         if (flags & TRANSPORT_PUSH_DRY_RUN)
 330                 args[i++] = "--dry-run";
 331         if (!(flags & TRANSPORT_PUSH_FORCE))
 332                 args[i++] = "--ignore-existing";
 333         args[i++] = temp_dir.buf;
 334         args[i++] = transport->url;
 335         args[i++] = NULL;
 336         if (run_command(&rsync))
 337                 result = error("Could not push to %s", transport->url);
 338
 339         if (remove_dir_recursively(&temp_dir, 0))
 340                 warning ("Could not remove temporary directory %s.",
 341                                 temp_dir.buf);
 342
 343         strbuf_release(&buf);
 344         strbuf_release(&temp_dir);
 345
 346         return result;
 347 }
 348
 349 /* Generic functions for using commit walkers */
 350
 351 static int fetch_objs_via_walker(struct transport *transport,
 352                                  int nr_objs, struct ref **to_fetch)
 353 {
 354         char *dest = xstrdup(transport->url);
 355         struct walker *walker = transport->data;
 356         char **objs = xmalloc(nr_objs * sizeof(*objs));
 357         int i;
 358
 359         walker->get_all = 1;
 360         walker->get_tree = 1;
 361         walker->get_history = 1;
 362         walker->get_verbosely = transport->verbose >= 0;
 363         walker->get_recover = 0;
 364
 365         for (i = 0; i < nr_objs; i++)
 366                 objs[i] = xstrdup(sha1_to_hex(to_fetch[i]->old_sha1));
 367
 368         if (walker_fetch(walker, nr_objs, objs, NULL, NULL))
 369                 die("Fetch failed.");
 370
 371         for (i = 0; i < nr_objs; i++)
 372                 free(objs[i]);
 373         free(objs);
 374         free(dest);
 375         return 0;
 376 }
 377
 378 static int disconnect_walker(struct transport *transport)
 379 {
 380         struct walker *walker = transport->data;
 381         if (walker)
 382                 walker_free(walker);
 383         return 0;
 384 }
 385
 386 #ifndef NO_CURL
 387 static int curl_transport_push(struct transport *transport, int refspec_nr, const char **refspec, int flags)
 388 {
 389         const char **argv;
 390         int argc;
 391         int err;
 392
 393         if (flags & TRANSPORT_PUSH_MIRROR)
 394                 return error("http transport does not support mirror mode");
 395
 396         argv = xmalloc((refspec_nr + 12) * sizeof(char *));
 397         argv[0] = "http-push";
 398         argc = 1;
 399         if (flags & TRANSPORT_PUSH_ALL)
 400                 argv[argc++] = "--all";
 401         if (flags & TRANSPORT_PUSH_FORCE)
 402                 argv[argc++] = "--force";
 403         if (flags & TRANSPORT_PUSH_DRY_RUN)
 404                 argv[argc++] = "--dry-run";
 405         if (flags & TRANSPORT_PUSH_VERBOSE)
 406                 argv[argc++] = "--verbose";
 407         argv[argc++] = transport->url;
 408         while (refspec_nr--)
 409                 argv[argc++] = *refspec++;
 410         argv[argc] = NULL;
 411         err = run_command_v_opt(argv, RUN_GIT_CMD);
 412         switch (err) {
 413         case -ERR_RUN_COMMAND_FORK:
 414                 error("unable to fork for %s", argv[0]);
 415         case -ERR_RUN_COMMAND_EXEC:
 416                 error("unable to exec %s", argv[0]);
 417                 break;
 418         case -ERR_RUN_COMMAND_WAITPID:
 419         case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
 420         case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
 421         case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
 422                 error("%s died with strange error", argv[0]);
 423         }
 424         return !!err;
 425 }
 426
 427 static int missing__target(int code, int result)
 428 {
 429         return  /* file:// URL -- do we ever use one??? */
 430                 (result == CURLE_FILE_COULDNT_READ_FILE) ||
 431                 /* http:// and https:// URL */
 432                 (code == 404 && result == CURLE_HTTP_RETURNED_ERROR) ||
 433                 /* ftp:// URL */
 434                 (code == 550 && result == CURLE_FTP_COULDNT_RETR_FILE)
 435                 ;
 436 }
 437
 438 #define missing_target(a) missing__target((a)->http_code, (a)->curl_result)
 439
 440 static struct ref *get_refs_via_curl(struct transport *transport)
 441 {
 442         struct buffer buffer;
 443         char *data, *start, *mid;
 444         char *ref_name;
 445         char *refs_url;
 446         int i = 0;
 447
 448         struct active_request_slot *slot;
 449         struct slot_results results;
 450
 451         struct ref *refs = NULL;
 452         struct ref *ref = NULL;
 453         struct ref *last_ref = NULL;
 454
 455         data = xmalloc(4096);
 456         buffer.size = 4096;
 457         buffer.posn = 0;
 458         buffer.buffer = data;
 459
 460         refs_url = xmalloc(strlen(transport->url) + 11);
 461         sprintf(refs_url, "%s/info/refs", transport->url);
 462
 463         http_init();
 464
 465         slot = get_active_slot();
 466         slot->results = &results;
 467         curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
 468         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
 469         curl_easy_setopt(slot->curl, CURLOPT_URL, refs_url);
 470         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, NULL);
 471         if (start_active_slot(slot)) {
 472                 run_active_slot(slot);
 473                 if (results.curl_result != CURLE_OK) {
 474                         if (missing_target(&results)) {
 475                                 free(buffer.buffer);
 476                                 return NULL;
 477                         } else {
 478                                 free(buffer.buffer);
 479                                 error("%s", curl_errorstr);
 480                                 return NULL;
 481                         }
 482                 }
 483         } else {
 484                 free(buffer.buffer);
 485                 error("Unable to start request");
 486                 return NULL;
 487         }
 488
 489         http_cleanup();
 490
 491         data = buffer.buffer;
 492         start = NULL;
 493         mid = data;
 494         while (i < buffer.posn) {
 495                 if (!start)
 496                         start = &data[i];
 497                 if (data[i] == '\t')
 498                         mid = &data[i];
 499                 if (data[i] == '\n') {
 500                         data[i] = 0;
 501                         ref_name = mid + 1;
 502                         ref = xmalloc(sizeof(struct ref) +
 503                                       strlen(ref_name) + 1);
 504                         memset(ref, 0, sizeof(struct ref));
 505                         strcpy(ref->name, ref_name);
 506                         get_sha1_hex(start, ref->old_sha1);
 507                         if (!refs)
 508                                 refs = ref;
 509                         if (last_ref)
 510                                 last_ref->next = ref;
 511                         last_ref = ref;
 512                         start = NULL;
 513                 }
 514                 i++;
 515         }
 516
 517         free(buffer.buffer);
 518
 519         return refs;
 520 }
 521
 522 static int fetch_objs_via_curl(struct transport *transport,
 523                                  int nr_objs, struct ref **to_fetch)
 524 {
 525         if (!transport->data)
 526                 transport->data = get_http_walker(transport->url);
 527         return fetch_objs_via_walker(transport, nr_objs, to_fetch);
 528 }
 529
 530 #endif
 531
 532 struct bundle_transport_data {
 533         int fd;
 534         struct bundle_header header;
 535 };
 536
 537 static struct ref *get_refs_from_bundle(struct transport *transport)
 538 {
 539         struct bundle_transport_data *data = transport->data;
 540         struct ref *result = NULL;
 541         int i;
 542
 543         if (data->fd > 0)
 544                 close(data->fd);
 545         data->fd = read_bundle_header(transport->url, &data->header);
 546         if (data->fd < 0)
 547                 die ("Could not read bundle '%s'.", transport->url);
 548         for (i = 0; i < data->header.references.nr; i++) {
 549                 struct ref_list_entry *e = data->header.references.list + i;
 550                 struct ref *ref = alloc_ref(strlen(e->name) + 1);
 551                 hashcpy(ref->old_sha1, e->sha1);
 552                 strcpy(ref->name, e->name);
 553                 ref->next = result;
 554                 result = ref;
 555         }
 556         return result;
 557 }
 558
 559 static int fetch_refs_from_bundle(struct transport *transport,
 560                                int nr_heads, struct ref **to_fetch)
 561 {
 562         struct bundle_transport_data *data = transport->data;
 563         return unbundle(&data->header, data->fd);
 564 }
 565
 566 static int close_bundle(struct transport *transport)
 567 {
 568         struct bundle_transport_data *data = transport->data;
 569         if (data->fd > 0)
 570                 close(data->fd);
 571         free(data);
 572         return 0;
 573 }
 574
 575 struct git_transport_data {
 576         unsigned thin : 1;
 577         unsigned keep : 1;
 578         int depth;
 579         const char *uploadpack;
 580         const char *receivepack;
 581 };
 582
 583 static int set_git_option(struct transport *connection,
 584                           const char *name, const char *value)
 585 {
 586         struct git_transport_data *data = connection->data;
 587         if (!strcmp(name, TRANS_OPT_UPLOADPACK)) {
 588                 data->uploadpack = value;
 589                 return 0;
 590         } else if (!strcmp(name, TRANS_OPT_RECEIVEPACK)) {
 591                 data->receivepack = value;
 592                 return 0;
 593         } else if (!strcmp(name, TRANS_OPT_THIN)) {
 594                 data->thin = !!value;
 595                 return 0;
 596         } else if (!strcmp(name, TRANS_OPT_KEEP)) {
 597                 data->keep = !!value;
 598                 return 0;
 599         } else if (!strcmp(name, TRANS_OPT_DEPTH)) {
 600                 if (!value)
 601                         data->depth = 0;
 602                 else
 603                         data->depth = atoi(value);
 604                 return 0;
 605         }
 606         return 1;
 607 }
 608
 609 static struct ref *get_refs_via_connect(struct transport *transport)
 610 {
 611         struct git_transport_data *data = transport->data;
 612         struct ref *refs;
 613         int fd[2];
 614         char *dest = xstrdup(transport->url);
 615         struct child_process *conn = git_connect(fd, dest, data->uploadpack, 0);
 616
 617         get_remote_heads(fd[0], &refs, 0, NULL, 0);
 618         packet_flush(fd[1]);
 619
 620         finish_connect(conn);
 621
 622         free(dest);
 623
 624         return refs;
 625 }
 626
 627 static int fetch_refs_via_pack(struct transport *transport,
 628                                int nr_heads, struct ref **to_fetch)
 629 {
 630         struct git_transport_data *data = transport->data;
 631         char **heads = xmalloc(nr_heads * sizeof(*heads));
 632         char **origh = xmalloc(nr_heads * sizeof(*origh));
 633         struct ref *refs;
 634         char *dest = xstrdup(transport->url);
 635         struct fetch_pack_args args;
 636         int i;
 637
 638         memset(&args, 0, sizeof(args));
 639         args.uploadpack = data->uploadpack;
 640         args.keep_pack = data->keep;
 641         args.lock_pack = 1;
 642         args.use_thin_pack = data->thin;
 643         args.verbose = transport->verbose > 0;
 644         args.depth = data->depth;
 645
 646         for (i = 0; i < nr_heads; i++)
 647                 origh[i] = heads[i] = xstrdup(to_fetch[i]->name);
 648         refs = fetch_pack(&args, dest, nr_heads, heads, &transport->pack_lockfile);
 649
 650         for (i = 0; i < nr_heads; i++)
 651                 free(origh[i]);
 652         free(origh);
 653         free(heads);
 654         free_refs(refs);
 655         free(dest);
 656         return 0;
 657 }
 658
 659 static int git_transport_push(struct transport *transport, int refspec_nr, const char **refspec, int flags)
 660 {
 661         struct git_transport_data *data = transport->data;
 662         struct send_pack_args args;
 663
 664         args.receivepack = data->receivepack;
 665         args.send_all = !!(flags & TRANSPORT_PUSH_ALL);
 666         args.send_mirror = !!(flags & TRANSPORT_PUSH_MIRROR);
 667         args.force_update = !!(flags & TRANSPORT_PUSH_FORCE);
 668         args.use_thin_pack = data->thin;
 669         args.verbose = !!(flags & TRANSPORT_PUSH_VERBOSE);
 670         args.dry_run = !!(flags & TRANSPORT_PUSH_DRY_RUN);
 671
 672         return send_pack(&args, transport->url, transport->remote, refspec_nr, refspec);
 673 }
 674
 675 static int disconnect_git(struct transport *transport)
 676 {
 677         free(transport->data);
 678         return 0;
 679 }
 680
 681 static int is_local(const char *url)
 682 {
 683         const char *colon = strchr(url, ':');
 684         const char *slash = strchr(url, '/');
 685         return !colon || (slash && slash < colon);
 686 }
 687
 688 static int is_file(const char *url)
 689 {
 690         struct stat buf;
 691         if (stat(url, &buf))
 692                 return 0;
 693         return S_ISREG(buf.st_mode);
 694 }
 695
 696 struct transport *transport_get(struct remote *remote, const char *url)
 697 {
 698         struct transport *ret = xcalloc(1, sizeof(*ret));
 699
 700         ret->remote = remote;
 701         ret->url = url;
 702
 703         if (!prefixcmp(url, "rsync://")) {
 704                 ret->get_refs_list = get_refs_via_rsync;
 705                 ret->fetch = fetch_objs_via_rsync;
 706                 ret->push = rsync_transport_push;
 707
 708         } else if (!prefixcmp(url, "http://")
 709                 || !prefixcmp(url, "https://")
 710                 || !prefixcmp(url, "ftp://")) {
 711 #ifdef NO_CURL
 712                 error("git was compiled without libcurl support.");
 713 #else
 714                 ret->get_refs_list = get_refs_via_curl;
 715                 ret->fetch = fetch_objs_via_curl;
 716                 ret->push = curl_transport_push;
 717 #endif
 718                 ret->disconnect = disconnect_walker;
 719
 720         } else if (is_local(url) && is_file(url)) {
 721                 struct bundle_transport_data *data = xcalloc(1, sizeof(*data));
 722                 ret->data = data;
 723                 ret->get_refs_list = get_refs_from_bundle;
 724                 ret->fetch = fetch_refs_from_bundle;
 725                 ret->disconnect = close_bundle;
 726
 727         } else {
 728                 struct git_transport_data *data = xcalloc(1, sizeof(*data));
 729                 ret->data = data;
 730                 ret->set_option = set_git_option;
 731                 ret->get_refs_list = get_refs_via_connect;
 732                 ret->fetch = fetch_refs_via_pack;
 733                 ret->push = git_transport_push;
 734                 ret->disconnect = disconnect_git;
 735
 736                 data->thin = 1;
 737                 data->uploadpack = "git-upload-pack";
 738                 if (remote && remote->uploadpack)
 739                         data->uploadpack = remote->uploadpack;
 740                 data->receivepack = "git-receive-pack";
 741                 if (remote && remote->receivepack)
 742                         data->receivepack = remote->receivepack;
 743         }
 744
 745         return ret;
 746 }
 747
 748 int transport_set_option(struct transport *transport,
 749                          const char *name, const char *value)
 750 {
 751         if (transport->set_option)
 752                 return transport->set_option(transport, name, value);
 753         return 1;
 754 }
 755
 756 int transport_push(struct transport *transport,
 757                    int refspec_nr, const char **refspec, int flags)
 758 {
 759         if (!transport->push)
 760                 return 1;
 761         return transport->push(transport, refspec_nr, refspec, flags);
 762 }
 763
 764 const struct ref *transport_get_remote_refs(struct transport *transport)
 765 {
 766         if (!transport->remote_refs)
 767                 transport->remote_refs = transport->get_refs_list(transport);
 768         return transport->remote_refs;
 769 }
 770
 771 int transport_fetch_refs(struct transport *transport, struct ref *refs)
 772 {
 773         int rc;
 774         int nr_heads = 0, nr_alloc = 0;
 775         struct ref **heads = NULL;
 776         struct ref *rm;
 777
 778         for (rm = refs; rm; rm = rm->next) {
 779                 if (rm->peer_ref &&
 780                     !hashcmp(rm->peer_ref->old_sha1, rm->old_sha1))
 781                         continue;
 782                 ALLOC_GROW(heads, nr_heads + 1, nr_alloc);
 783                 heads[nr_heads++] = rm;
 784         }
 785
 786         rc = transport->fetch(transport, nr_heads, heads);
 787         free(heads);
 788         return rc;
 789 }
 790
 791 void transport_unlock_pack(struct transport *transport)
 792 {
 793         if (transport->pack_lockfile) {
 794                 unlink(transport->pack_lockfile);
 795                 free(transport->pack_lockfile);
 796                 transport->pack_lockfile = NULL;
 797         }
 798 }
 799
 800 int transport_disconnect(struct transport *transport)
 801 {
 802         int ret = 0;
 803         if (transport->disconnect)
 804                 ret = transport->disconnect(transport);
 805         free(transport);
 806         return ret;
 807 }