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 "walker.h"
  10 #include "bundle.h"
  11 #include "dir.h"
  12 #include "refs.h"
  13
  14 /* rsync support */
  15
  16 /*
  17  * We copy packed-refs and refs/ into a temporary file, then read the
  18  * loose refs recursively (sorting whenever possible), and then inserting
  19  * those packed refs that are not yet in the list (not validating, but
  20  * assuming that the file is sorted).
  21  *
  22  * Appears refactoring this from refs.c is too cumbersome.
  23  */
  24
  25 static int str_cmp(const void *a, const void *b)
  26 {
  27         const char *s1 = a;
  28         const char *s2 = b;
  29
  30         return strcmp(s1, s2);
  31 }
  32
  33 /* path->buf + name_offset is expected to point to "refs/" */
  34
  35 static int read_loose_refs(struct strbuf *path, int name_offset,
  36                 struct ref **tail)
  37 {
  38         DIR *dir = opendir(path->buf);
  39         struct dirent *de;
  40         struct {
  41                 char **entries;
  42                 int nr, alloc;
  43         } list;
  44         int i, pathlen;
  45
  46         if (!dir)
  47                 return -1;
  48
  49         memset (&list, 0, sizeof(list));
  50
  51         while ((de = readdir(dir))) {
  52                 if (de->d_name[0] == '.' && (de->d_name[1] == '\0' ||
  53                                 (de->d_name[1] == '.' &&
  54                                  de->d_name[2] == '\0')))
  55                         continue;
  56                 ALLOC_GROW(list.entries, list.nr + 1, list.alloc);
  57                 list.entries[list.nr++] = xstrdup(de->d_name);
  58         }
  59         closedir(dir);
  60
  61         /* sort the list */
  62
  63         qsort(list.entries, list.nr, sizeof(char *), str_cmp);
  64
  65         pathlen = path->len;
  66         strbuf_addch(path, '/');
  67
  68         for (i = 0; i < list.nr; i++, strbuf_setlen(path, pathlen + 1)) {
  69                 strbuf_addstr(path, list.entries[i]);
  70                 if (read_loose_refs(path, name_offset, tail)) {
  71                         int fd = open(path->buf, O_RDONLY);
  72                         char buffer[40];
  73                         struct ref *next;
  74
  75                         if (fd < 0)
  76                                 continue;
  77                         next = alloc_ref(path->len - name_offset + 1);
  78                         if (read_in_full(fd, buffer, 40) != 40 ||
  79                                         get_sha1_hex(buffer, next->old_sha1)) {
  80                                 close(fd);
  81                                 free(next);
  82                                 continue;
  83                         }
  84                         close(fd);
  85                         strcpy(next->name, path->buf + name_offset);
  86                         (*tail)->next = next;
  87                         *tail = next;
  88                 }
  89         }
  90         strbuf_setlen(path, pathlen);
  91
  92         for (i = 0; i < list.nr; i++)
  93                 free(list.entries[i]);
  94         free(list.entries);
  95
  96         return 0;
  97 }
  98
  99 /* insert the packed refs for which no loose refs were found */
 100
 101 static void insert_packed_refs(const char *packed_refs, struct ref **list)
 102 {
 103         FILE *f = fopen(packed_refs, "r");
 104         static char buffer[PATH_MAX];
 105
 106         if (!f)
 107                 return;
 108
 109         for (;;) {
 110                 int cmp = cmp, len;
 111
 112                 if (!fgets(buffer, sizeof(buffer), f)) {
 113                         fclose(f);
 114                         return;
 115                 }
 116
 117                 if (hexval(buffer[0]) > 0xf)
 118                         continue;
 119                 len = strlen(buffer);
 120                 if (buffer[len - 1] == '\n')
 121                         buffer[--len] = '\0';
 122                 if (len < 41)
 123                         continue;
 124                 while ((*list)->next &&
 125                                 (cmp = strcmp(buffer + 41,
 126                                       (*list)->next->name)) > 0)
 127                         list = &(*list)->next;
 128                 if (!(*list)->next || cmp < 0) {
 129                         struct ref *next = alloc_ref(len - 40);
 130                         buffer[40] = '\0';
 131                         if (get_sha1_hex(buffer, next->old_sha1)) {
 132                                 warning ("invalid SHA-1: %s", buffer);
 133                                 free(next);
 134                                 continue;
 135                         }
 136                         strcpy(next->name, buffer + 41);
 137                         next->next = (*list)->next;
 138                         (*list)->next = next;
 139                         list = &(*list)->next;
 140                 }
 141         }
 142 }
 143
 144 static struct ref *get_refs_via_rsync(const struct transport *transport)
 145 {
 146         struct strbuf buf = STRBUF_INIT, temp_dir = STRBUF_INIT;
 147         struct ref dummy, *tail = &dummy;
 148         struct child_process rsync;
 149         const char *args[5];
 150         int temp_dir_len;
 151
 152         /* copy the refs to the temporary directory */
 153
 154         strbuf_addstr(&temp_dir, git_path("rsync-refs-XXXXXX"));
 155         if (!mkdtemp(temp_dir.buf))
 156                 die ("Could not make temporary directory");
 157         temp_dir_len = temp_dir.len;
 158
 159         strbuf_addstr(&buf, transport->url);
 160         strbuf_addstr(&buf, "/refs");
 161
 162         memset(&rsync, 0, sizeof(rsync));
 163         rsync.argv = args;
 164         rsync.stdout_to_stderr = 1;
 165         args[0] = "rsync";
 166         args[1] = (transport->verbose > 0) ? "-rv" : "-r";
 167         args[2] = buf.buf;
 168         args[3] = temp_dir.buf;
 169         args[4] = NULL;
 170
 171         if (run_command(&rsync))
 172                 die ("Could not run rsync to get refs");
 173
 174         strbuf_reset(&buf);
 175         strbuf_addstr(&buf, transport->url);
 176         strbuf_addstr(&buf, "/packed-refs");
 177
 178         args[2] = buf.buf;
 179
 180         if (run_command(&rsync))
 181                 die ("Could not run rsync to get refs");
 182
 183         /* read the copied refs */
 184
 185         strbuf_addstr(&temp_dir, "/refs");
 186         read_loose_refs(&temp_dir, temp_dir_len + 1, &tail);
 187         strbuf_setlen(&temp_dir, temp_dir_len);
 188
 189         tail = &dummy;
 190         strbuf_addstr(&temp_dir, "/packed-refs");
 191         insert_packed_refs(temp_dir.buf, &tail);
 192         strbuf_setlen(&temp_dir, temp_dir_len);
 193
 194         if (remove_dir_recursively(&temp_dir, 0))
 195                 warning ("Error removing temporary directory %s.",
 196                                 temp_dir.buf);
 197
 198         strbuf_release(&buf);
 199         strbuf_release(&temp_dir);
 200
 201         return dummy.next;
 202 }
 203
 204 static int fetch_objs_via_rsync(struct transport *transport,
 205                                  int nr_objs, struct ref **to_fetch)
 206 {
 207         struct strbuf buf = STRBUF_INIT;
 208         struct child_process rsync;
 209         const char *args[8];
 210         int result;
 211
 212         strbuf_addstr(&buf, transport->url);
 213         strbuf_addstr(&buf, "/objects/");
 214
 215         memset(&rsync, 0, sizeof(rsync));
 216         rsync.argv = args;
 217         rsync.stdout_to_stderr = 1;
 218         args[0] = "rsync";
 219         args[1] = (transport->verbose > 0) ? "-rv" : "-r";
 220         args[2] = "--ignore-existing";
 221         args[3] = "--exclude";
 222         args[4] = "info";
 223         args[5] = buf.buf;
 224         args[6] = get_object_directory();
 225         args[7] = NULL;
 226
 227         /* NEEDSWORK: handle one level of alternates */
 228         result = run_command(&rsync);
 229
 230         strbuf_release(&buf);
 231
 232         return result;
 233 }
 234
 235 static int write_one_ref(const char *name, const unsigned char *sha1,
 236                 int flags, void *data)
 237 {
 238         struct strbuf *buf = data;
 239         int len = buf->len;
 240         FILE *f;
 241
 242         /* when called via for_each_ref(), flags is non-zero */
 243         if (flags && prefixcmp(name, "refs/heads/") &&
 244                         prefixcmp(name, "refs/tags/"))
 245                 return 0;
 246
 247         strbuf_addstr(buf, name);
 248         if (safe_create_leading_directories(buf->buf) ||
 249                         !(f = fopen(buf->buf, "w")) ||
 250                         fprintf(f, "%s\n", sha1_to_hex(sha1)) < 0 ||
 251                         fclose(f))
 252                 return error("problems writing temporary file %s", buf->buf);
 253         strbuf_setlen(buf, len);
 254         return 0;
 255 }
 256
 257 static int write_refs_to_temp_dir(struct strbuf *temp_dir,
 258                 int refspec_nr, const char **refspec)
 259 {
 260         int i;
 261
 262         for (i = 0; i < refspec_nr; i++) {
 263                 unsigned char sha1[20];
 264                 char *ref;
 265
 266                 if (dwim_ref(refspec[i], strlen(refspec[i]), sha1, &ref) != 1)
 267                         return error("Could not get ref %s", refspec[i]);
 268
 269                 if (write_one_ref(ref, sha1, 0, temp_dir)) {
 270                         free(ref);
 271                         return -1;
 272                 }
 273                 free(ref);
 274         }
 275         return 0;
 276 }
 277
 278 static int rsync_transport_push(struct transport *transport,
 279                 int refspec_nr, const char **refspec, int flags)
 280 {
 281         struct strbuf buf = STRBUF_INIT, temp_dir = STRBUF_INIT;
 282         int result = 0, i;
 283         struct child_process rsync;
 284         const char *args[10];
 285
 286         /* first push the objects */
 287
 288         strbuf_addstr(&buf, transport->url);
 289         strbuf_addch(&buf, '/');
 290
 291         memset(&rsync, 0, sizeof(rsync));
 292         rsync.argv = args;
 293         rsync.stdout_to_stderr = 1;
 294         i = 0;
 295         args[i++] = "rsync";
 296         args[i++] = "-a";
 297         if (flags & TRANSPORT_PUSH_DRY_RUN)
 298                 args[i++] = "--dry-run";
 299         if (transport->verbose > 0)
 300                 args[i++] = "-v";
 301         args[i++] = "--ignore-existing";
 302         args[i++] = "--exclude";
 303         args[i++] = "info";
 304         args[i++] = get_object_directory();
 305         args[i++] = buf.buf;
 306         args[i++] = NULL;
 307
 308         if (run_command(&rsync))
 309                 return error("Could not push objects to %s", transport->url);
 310
 311         /* copy the refs to the temporary directory; they could be packed. */
 312
 313         strbuf_addstr(&temp_dir, git_path("rsync-refs-XXXXXX"));
 314         if (!mkdtemp(temp_dir.buf))
 315                 die ("Could not make temporary directory");
 316         strbuf_addch(&temp_dir, '/');
 317
 318         if (flags & TRANSPORT_PUSH_ALL) {
 319                 if (for_each_ref(write_one_ref, &temp_dir))
 320                         return -1;
 321         } else if (write_refs_to_temp_dir(&temp_dir, refspec_nr, refspec))
 322                 return -1;
 323
 324         i = 2;
 325         if (flags & TRANSPORT_PUSH_DRY_RUN)
 326                 args[i++] = "--dry-run";
 327         if (!(flags & TRANSPORT_PUSH_FORCE))
 328                 args[i++] = "--ignore-existing";
 329         args[i++] = temp_dir.buf;
 330         args[i++] = transport->url;
 331         args[i++] = NULL;
 332         if (run_command(&rsync))
 333                 result = error("Could not push to %s", transport->url);
 334
 335         if (remove_dir_recursively(&temp_dir, 0))
 336                 warning ("Could not remove temporary directory %s.",
 337                                 temp_dir.buf);
 338
 339         strbuf_release(&buf);
 340         strbuf_release(&temp_dir);
 341
 342         return result;
 343 }
 344
 345 /* Generic functions for using commit walkers */
 346
 347 #ifndef NO_CURL /* http fetch is the only user */
 348 static int fetch_objs_via_walker(struct transport *transport,
 349                                  int nr_objs, struct ref **to_fetch)
 350 {
 351         char *dest = xstrdup(transport->url);
 352         struct walker *walker = transport->data;
 353         char **objs = xmalloc(nr_objs * sizeof(*objs));
 354         int i;
 355
 356         walker->get_all = 1;
 357         walker->get_tree = 1;
 358         walker->get_history = 1;
 359         walker->get_verbosely = transport->verbose >= 0;
 360         walker->get_recover = 0;
 361
 362         for (i = 0; i < nr_objs; i++)
 363                 objs[i] = xstrdup(sha1_to_hex(to_fetch[i]->old_sha1));
 364
 365         if (walker_fetch(walker, nr_objs, objs, NULL, NULL))
 366                 die("Fetch failed.");
 367
 368         for (i = 0; i < nr_objs; i++)
 369                 free(objs[i]);
 370         free(objs);
 371         free(dest);
 372         return 0;
 373 }
 374 #endif /* NO_CURL */
 375
 376 static int disconnect_walker(struct transport *transport)
 377 {
 378         struct walker *walker = transport->data;
 379         if (walker)
 380                 walker_free(walker);
 381         return 0;
 382 }
 383
 384 #ifndef NO_CURL
 385 static int curl_transport_push(struct transport *transport, int refspec_nr, const char **refspec, int flags)
 386 {
 387         const char **argv;
 388         int argc;
 389         int err;
 390
 391         argv = xmalloc((refspec_nr + 12) * sizeof(char *));
 392         argv[0] = "http-push";
 393         argc = 1;
 394         if (flags & TRANSPORT_PUSH_ALL)
 395                 argv[argc++] = "--all";
 396         if (flags & TRANSPORT_PUSH_FORCE)
 397                 argv[argc++] = "--force";
 398         if (flags & TRANSPORT_PUSH_DRY_RUN)
 399                 argv[argc++] = "--dry-run";
 400         if (flags & TRANSPORT_PUSH_VERBOSE)
 401                 argv[argc++] = "--verbose";
 402         argv[argc++] = transport->url;
 403         while (refspec_nr--)
 404                 argv[argc++] = *refspec++;
 405         argv[argc] = NULL;
 406         err = run_command_v_opt(argv, RUN_GIT_CMD);
 407         switch (err) {
 408         case -ERR_RUN_COMMAND_FORK:
 409                 error("unable to fork for %s", argv[0]);
 410         case -ERR_RUN_COMMAND_EXEC:
 411                 error("unable to exec %s", argv[0]);
 412                 break;
 413         case -ERR_RUN_COMMAND_WAITPID:
 414         case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
 415         case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
 416         case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
 417                 error("%s died with strange error", argv[0]);
 418         }
 419         return !!err;
 420 }
 421
 422 static int missing__target(int code, int result)
 423 {
 424         return  /* file:// URL -- do we ever use one??? */
 425                 (result == CURLE_FILE_COULDNT_READ_FILE) ||
 426                 /* http:// and https:// URL */
 427                 (code == 404 && result == CURLE_HTTP_RETURNED_ERROR) ||
 428                 /* ftp:// URL */
 429                 (code == 550 && result == CURLE_FTP_COULDNT_RETR_FILE)
 430                 ;
 431 }
 432
 433 #define missing_target(a) missing__target((a)->http_code, (a)->curl_result)
 434
 435 static struct ref *get_refs_via_curl(const struct transport *transport)
 436 {
 437         struct buffer buffer;
 438         char *data, *start, *mid;
 439         char *ref_name;
 440         char *refs_url;
 441         int i = 0;
 442
 443         struct active_request_slot *slot;
 444         struct slot_results results;
 445
 446         struct ref *refs = NULL;
 447         struct ref *ref = NULL;
 448         struct ref *last_ref = NULL;
 449
 450         data = xmalloc(4096);
 451         buffer.size = 4096;
 452         buffer.posn = 0;
 453         buffer.buffer = data;
 454
 455         refs_url = xmalloc(strlen(transport->url) + 11);
 456         sprintf(refs_url, "%s/info/refs", transport->url);
 457
 458         http_init();
 459
 460         slot = get_active_slot();
 461         slot->results = &results;
 462         curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
 463         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
 464         curl_easy_setopt(slot->curl, CURLOPT_URL, refs_url);
 465         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, NULL);
 466         if (start_active_slot(slot)) {
 467                 run_active_slot(slot);
 468                 if (results.curl_result != CURLE_OK) {
 469                         if (missing_target(&results)) {
 470                                 free(buffer.buffer);
 471                                 return NULL;
 472                         } else {
 473                                 free(buffer.buffer);
 474                                 error("%s", curl_errorstr);
 475                                 return NULL;
 476                         }
 477                 }
 478         } else {
 479                 free(buffer.buffer);
 480                 error("Unable to start request");
 481                 return NULL;
 482         }
 483
 484         http_cleanup();
 485
 486         data = buffer.buffer;
 487         start = NULL;
 488         mid = data;
 489         while (i < buffer.posn) {
 490                 if (!start)
 491                         start = &data[i];
 492                 if (data[i] == '\t')
 493                         mid = &data[i];
 494                 if (data[i] == '\n') {
 495                         data[i] = 0;
 496                         ref_name = mid + 1;
 497                         ref = xmalloc(sizeof(struct ref) +
 498                                       strlen(ref_name) + 1);
 499                         memset(ref, 0, sizeof(struct ref));
 500                         strcpy(ref->name, ref_name);
 501                         get_sha1_hex(start, ref->old_sha1);
 502                         if (!refs)
 503                                 refs = ref;
 504                         if (last_ref)
 505                                 last_ref->next = ref;
 506                         last_ref = ref;
 507                         start = NULL;
 508                 }
 509                 i++;
 510         }
 511
 512         free(buffer.buffer);
 513
 514         return refs;
 515 }
 516
 517 static int fetch_objs_via_curl(struct transport *transport,
 518                                  int nr_objs, struct ref **to_fetch)
 519 {
 520         if (!transport->data)
 521                 transport->data = get_http_walker(transport->url);
 522         return fetch_objs_via_walker(transport, nr_objs, to_fetch);
 523 }
 524
 525 #endif
 526
 527 struct bundle_transport_data {
 528         int fd;
 529         struct bundle_header header;
 530 };
 531
 532 static struct ref *get_refs_from_bundle(const struct transport *transport)
 533 {
 534         struct bundle_transport_data *data = transport->data;
 535         struct ref *result = NULL;
 536         int i;
 537
 538         if (data->fd > 0)
 539                 close(data->fd);
 540         data->fd = read_bundle_header(transport->url, &data->header);
 541         if (data->fd < 0)
 542                 die ("Could not read bundle '%s'.", transport->url);
 543         for (i = 0; i < data->header.references.nr; i++) {
 544                 struct ref_list_entry *e = data->header.references.list + i;
 545                 struct ref *ref = alloc_ref(strlen(e->name) + 1);
 546                 hashcpy(ref->old_sha1, e->sha1);
 547                 strcpy(ref->name, e->name);
 548                 ref->next = result;
 549                 result = ref;
 550         }
 551         return result;
 552 }
 553
 554 static int fetch_refs_from_bundle(struct transport *transport,
 555                                int nr_heads, struct ref **to_fetch)
 556 {
 557         struct bundle_transport_data *data = transport->data;
 558         return unbundle(&data->header, data->fd);
 559 }
 560
 561 static int close_bundle(struct transport *transport)
 562 {
 563         struct bundle_transport_data *data = transport->data;
 564         if (data->fd > 0)
 565                 close(data->fd);
 566         free(data);
 567         return 0;
 568 }
 569
 570 struct git_transport_data {
 571         unsigned thin : 1;
 572         unsigned keep : 1;
 573         int depth;
 574         const char *uploadpack;
 575         const char *receivepack;
 576 };
 577
 578 static int set_git_option(struct transport *connection,
 579                           const char *name, const char *value)
 580 {
 581         struct git_transport_data *data = connection->data;
 582         if (!strcmp(name, TRANS_OPT_UPLOADPACK)) {
 583                 data->uploadpack = value;
 584                 return 0;
 585         } else if (!strcmp(name, TRANS_OPT_RECEIVEPACK)) {
 586                 data->receivepack = value;
 587                 return 0;
 588         } else if (!strcmp(name, TRANS_OPT_THIN)) {
 589                 data->thin = !!value;
 590                 return 0;
 591         } else if (!strcmp(name, TRANS_OPT_KEEP)) {
 592                 data->keep = !!value;
 593                 return 0;
 594         } else if (!strcmp(name, TRANS_OPT_DEPTH)) {
 595                 if (!value)
 596                         data->depth = 0;
 597                 else
 598                         data->depth = atoi(value);
 599                 return 0;
 600         }
 601         return 1;
 602 }
 603
 604 static struct ref *get_refs_via_connect(const struct transport *transport)
 605 {
 606         struct git_transport_data *data = transport->data;
 607         struct ref *refs;
 608         int fd[2];
 609         char *dest = xstrdup(transport->url);
 610         struct child_process *conn = git_connect(fd, dest, data->uploadpack, 0);
 611
 612         get_remote_heads(fd[0], &refs, 0, NULL, 0);
 613         packet_flush(fd[1]);
 614
 615         finish_connect(conn);
 616
 617         free(dest);
 618
 619         return refs;
 620 }
 621
 622 static int fetch_refs_via_pack(struct transport *transport,
 623                                int nr_heads, struct ref **to_fetch)
 624 {
 625         struct git_transport_data *data = transport->data;
 626         char **heads = xmalloc(nr_heads * sizeof(*heads));
 627         char **origh = xmalloc(nr_heads * sizeof(*origh));
 628         struct ref *refs;
 629         char *dest = xstrdup(transport->url);
 630         struct fetch_pack_args args;
 631         int i;
 632
 633         memset(&args, 0, sizeof(args));
 634         args.uploadpack = data->uploadpack;
 635         args.keep_pack = data->keep;
 636         args.lock_pack = 1;
 637         args.use_thin_pack = data->thin;
 638         args.verbose = transport->verbose > 0;
 639         args.depth = data->depth;
 640
 641         for (i = 0; i < nr_heads; i++)
 642                 origh[i] = heads[i] = xstrdup(to_fetch[i]->name);
 643         refs = fetch_pack(&args, dest, nr_heads, heads, &transport->pack_lockfile);
 644
 645         for (i = 0; i < nr_heads; i++)
 646                 free(origh[i]);
 647         free(origh);
 648         free(heads);
 649         free_refs(refs);
 650         free(dest);
 651         return 0;
 652 }
 653
 654 static int git_transport_push(struct transport *transport, int refspec_nr, const char **refspec, int flags)
 655 {
 656         struct git_transport_data *data = transport->data;
 657         const char **argv;
 658         char *rem;
 659         int argc;
 660         int err;
 661
 662         argv = xmalloc((refspec_nr + 12) * sizeof(char *));
 663         argv[0] = "send-pack";
 664         argc = 1;
 665         if (flags & TRANSPORT_PUSH_ALL)
 666                 argv[argc++] = "--all";
 667         if (flags & TRANSPORT_PUSH_FORCE)
 668                 argv[argc++] = "--force";
 669         if (flags & TRANSPORT_PUSH_DRY_RUN)
 670                 argv[argc++] = "--dry-run";
 671         if (flags & TRANSPORT_PUSH_VERBOSE)
 672                 argv[argc++] = "--verbose";
 673         if (data->receivepack) {
 674                 char *rp = xmalloc(strlen(data->receivepack) + 16);
 675                 sprintf(rp, "--receive-pack=%s", data->receivepack);
 676                 argv[argc++] = rp;
 677         }
 678         if (data->thin)
 679                 argv[argc++] = "--thin";
 680         rem = xmalloc(strlen(transport->remote->name) + 10);
 681         sprintf(rem, "--remote=%s", transport->remote->name);
 682         argv[argc++] = rem;
 683         argv[argc++] = transport->url;
 684         while (refspec_nr--)
 685                 argv[argc++] = *refspec++;
 686         argv[argc] = NULL;
 687         err = run_command_v_opt(argv, RUN_GIT_CMD);
 688         switch (err) {
 689         case -ERR_RUN_COMMAND_FORK:
 690                 error("unable to fork for %s", argv[0]);
 691         case -ERR_RUN_COMMAND_EXEC:
 692                 error("unable to exec %s", argv[0]);
 693                 break;
 694         case -ERR_RUN_COMMAND_WAITPID:
 695         case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
 696         case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
 697         case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
 698                 error("%s died with strange error", argv[0]);
 699         }
 700         return !!err;
 701 }
 702
 703 static int disconnect_git(struct transport *transport)
 704 {
 705         free(transport->data);
 706         return 0;
 707 }
 708
 709 static int is_local(const char *url)
 710 {
 711         const char *colon = strchr(url, ':');
 712         const char *slash = strchr(url, '/');
 713         return !colon || (slash && slash < colon);
 714 }
 715
 716 static int is_file(const char *url)
 717 {
 718         struct stat buf;
 719         if (stat(url, &buf))
 720                 return 0;
 721         return S_ISREG(buf.st_mode);
 722 }
 723
 724 struct transport *transport_get(struct remote *remote, const char *url)
 725 {
 726         struct transport *ret = xcalloc(1, sizeof(*ret));
 727
 728         ret->remote = remote;
 729         ret->url = url;
 730
 731         if (!prefixcmp(url, "rsync://")) {
 732                 ret->get_refs_list = get_refs_via_rsync;
 733                 ret->fetch = fetch_objs_via_rsync;
 734                 ret->push = rsync_transport_push;
 735
 736         } else if (!prefixcmp(url, "http://")
 737                 || !prefixcmp(url, "https://")
 738                 || !prefixcmp(url, "ftp://")) {
 739 #ifdef NO_CURL
 740                 error("git was compiled without libcurl support.");
 741 #else
 742                 ret->get_refs_list = get_refs_via_curl;
 743                 ret->fetch = fetch_objs_via_curl;
 744                 ret->push = curl_transport_push;
 745 #endif
 746                 ret->disconnect = disconnect_walker;
 747
 748         } else if (is_local(url) && is_file(url)) {
 749                 struct bundle_transport_data *data = xcalloc(1, sizeof(*data));
 750                 ret->data = data;
 751                 ret->get_refs_list = get_refs_from_bundle;
 752                 ret->fetch = fetch_refs_from_bundle;
 753                 ret->disconnect = close_bundle;
 754
 755         } else {
 756                 struct git_transport_data *data = xcalloc(1, sizeof(*data));
 757                 ret->data = data;
 758                 ret->set_option = set_git_option;
 759                 ret->get_refs_list = get_refs_via_connect;
 760                 ret->fetch = fetch_refs_via_pack;
 761                 ret->push = git_transport_push;
 762                 ret->disconnect = disconnect_git;
 763
 764                 data->thin = 1;
 765                 data->uploadpack = "git-upload-pack";
 766                 if (remote && remote->uploadpack)
 767                         data->uploadpack = remote->uploadpack;
 768                 data->receivepack = "git-receive-pack";
 769                 if (remote && remote->receivepack)
 770                         data->receivepack = remote->receivepack;
 771         }
 772
 773         return ret;
 774 }
 775
 776 int transport_set_option(struct transport *transport,
 777                          const char *name, const char *value)
 778 {
 779         if (transport->set_option)
 780                 return transport->set_option(transport, name, value);
 781         return 1;
 782 }
 783
 784 int transport_push(struct transport *transport,
 785                    int refspec_nr, const char **refspec, int flags)
 786 {
 787         if (!transport->push)
 788                 return 1;
 789         return transport->push(transport, refspec_nr, refspec, flags);
 790 }
 791
 792 struct ref *transport_get_remote_refs(struct transport *transport)
 793 {
 794         if (!transport->remote_refs)
 795                 transport->remote_refs = transport->get_refs_list(transport);
 796         return transport->remote_refs;
 797 }
 798
 799 int transport_fetch_refs(struct transport *transport, struct ref *refs)
 800 {
 801         int rc;
 802         int nr_heads = 0, nr_alloc = 0;
 803         struct ref **heads = NULL;
 804         struct ref *rm;
 805
 806         for (rm = refs; rm; rm = rm->next) {
 807                 if (rm->peer_ref &&
 808                     !hashcmp(rm->peer_ref->old_sha1, rm->old_sha1))
 809                         continue;
 810                 ALLOC_GROW(heads, nr_heads + 1, nr_alloc);
 811                 heads[nr_heads++] = rm;
 812         }
 813
 814         rc = transport->fetch(transport, nr_heads, heads);
 815         free(heads);
 816         return rc;
 817 }
 818
 819 void transport_unlock_pack(struct transport *transport)
 820 {
 821         if (transport->pack_lockfile) {
 822                 unlink(transport->pack_lockfile);
 823                 free(transport->pack_lockfile);
 824                 transport->pack_lockfile = NULL;
 825         }
 826 }
 827
 828 int transport_disconnect(struct transport *transport)
 829 {
 830         int ret = 0;
 831         if (transport->disconnect)
 832                 ret = transport->disconnect(transport);
 833         free(transport);
 834         return ret;
 835 }