Andrew's git / gitweb.git / transport.c
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transport.con commit Allow cloning to an existing empty directory (55892d2)
   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
  26static 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
  36static 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 (is_dot_or_dotdot(de->d_name))
  54                        continue;
  55                ALLOC_GROW(list.entries, list.nr + 1, list.alloc);
  56                list.entries[list.nr++] = xstrdup(de->d_name);
  57        }
  58        closedir(dir);
  59
  60        /* sort the list */
  61
  62        qsort(list.entries, list.nr, sizeof(char *), str_cmp);
  63
  64        pathlen = path->len;
  65        strbuf_addch(path, '/');
  66
  67        for (i = 0; i < list.nr; i++, strbuf_setlen(path, pathlen + 1)) {
  68                strbuf_addstr(path, list.entries[i]);
  69                if (read_loose_refs(path, name_offset, tail)) {
  70                        int fd = open(path->buf, O_RDONLY);
  71                        char buffer[40];
  72                        struct ref *next;
  73
  74                        if (fd < 0)
  75                                continue;
  76                        next = alloc_ref(path->buf + name_offset);
  77                        if (read_in_full(fd, buffer, 40) != 40 ||
  78                                        get_sha1_hex(buffer, next->old_sha1)) {
  79                                close(fd);
  80                                free(next);
  81                                continue;
  82                        }
  83                        close(fd);
  84                        (*tail)->next = next;
  85                        *tail = next;
  86                }
  87        }
  88        strbuf_setlen(path, pathlen);
  89
  90        for (i = 0; i < list.nr; i++)
  91                free(list.entries[i]);
  92        free(list.entries);
  93
  94        return 0;
  95}
  96
  97/* insert the packed refs for which no loose refs were found */
  98
  99static void insert_packed_refs(const char *packed_refs, struct ref **list)
 100{
 101        FILE *f = fopen(packed_refs, "r");
 102        static char buffer[PATH_MAX];
 103
 104        if (!f)
 105                return;
 106
 107        for (;;) {
 108                int cmp = cmp, len;
 109
 110                if (!fgets(buffer, sizeof(buffer), f)) {
 111                        fclose(f);
 112                        return;
 113                }
 114
 115                if (hexval(buffer[0]) > 0xf)
 116                        continue;
 117                len = strlen(buffer);
 118                if (len && buffer[len - 1] == '\n')
 119                        buffer[--len] = '\0';
 120                if (len < 41)
 121                        continue;
 122                while ((*list)->next &&
 123                                (cmp = strcmp(buffer + 41,
 124                                      (*list)->next->name)) > 0)
 125                        list = &(*list)->next;
 126                if (!(*list)->next || cmp < 0) {
 127                        struct ref *next = alloc_ref(buffer + 41);
 128                        buffer[40] = '\0';
 129                        if (get_sha1_hex(buffer, next->old_sha1)) {
 130                                warning ("invalid SHA-1: %s", buffer);
 131                                free(next);
 132                                continue;
 133                        }
 134                        next->next = (*list)->next;
 135                        (*list)->next = next;
 136                        list = &(*list)->next;
 137                }
 138        }
 139}
 140
 141static struct ref *get_refs_via_rsync(struct transport *transport)
 142{
 143        struct strbuf buf = STRBUF_INIT, temp_dir = STRBUF_INIT;
 144        struct ref dummy, *tail = &dummy;
 145        struct child_process rsync;
 146        const char *args[5];
 147        int temp_dir_len;
 148
 149        /* copy the refs to the temporary directory */
 150
 151        strbuf_addstr(&temp_dir, git_path("rsync-refs-XXXXXX"));
 152        if (!mkdtemp(temp_dir.buf))
 153                die ("Could not make temporary directory");
 154        temp_dir_len = temp_dir.len;
 155
 156        strbuf_addstr(&buf, transport->url);
 157        strbuf_addstr(&buf, "/refs");
 158
 159        memset(&rsync, 0, sizeof(rsync));
 160        rsync.argv = args;
 161        rsync.stdout_to_stderr = 1;
 162        args[0] = "rsync";
 163        args[1] = (transport->verbose > 0) ? "-rv" : "-r";
 164        args[2] = buf.buf;
 165        args[3] = temp_dir.buf;
 166        args[4] = NULL;
 167
 168        if (run_command(&rsync))
 169                die ("Could not run rsync to get refs");
 170
 171        strbuf_reset(&buf);
 172        strbuf_addstr(&buf, transport->url);
 173        strbuf_addstr(&buf, "/packed-refs");
 174
 175        args[2] = buf.buf;
 176
 177        if (run_command(&rsync))
 178                die ("Could not run rsync to get refs");
 179
 180        /* read the copied refs */
 181
 182        strbuf_addstr(&temp_dir, "/refs");
 183        read_loose_refs(&temp_dir, temp_dir_len + 1, &tail);
 184        strbuf_setlen(&temp_dir, temp_dir_len);
 185
 186        tail = &dummy;
 187        strbuf_addstr(&temp_dir, "/packed-refs");
 188        insert_packed_refs(temp_dir.buf, &tail);
 189        strbuf_setlen(&temp_dir, temp_dir_len);
 190
 191        if (remove_dir_recursively(&temp_dir, 0))
 192                warning ("Error removing temporary directory %s.",
 193                                temp_dir.buf);
 194
 195        strbuf_release(&buf);
 196        strbuf_release(&temp_dir);
 197
 198        return dummy.next;
 199}
 200
 201static int fetch_objs_via_rsync(struct transport *transport,
 202                                int nr_objs, const struct ref **to_fetch)
 203{
 204        struct strbuf buf = STRBUF_INIT;
 205        struct child_process rsync;
 206        const char *args[8];
 207        int result;
 208
 209        strbuf_addstr(&buf, transport->url);
 210        strbuf_addstr(&buf, "/objects/");
 211
 212        memset(&rsync, 0, sizeof(rsync));
 213        rsync.argv = args;
 214        rsync.stdout_to_stderr = 1;
 215        args[0] = "rsync";
 216        args[1] = (transport->verbose > 0) ? "-rv" : "-r";
 217        args[2] = "--ignore-existing";
 218        args[3] = "--exclude";
 219        args[4] = "info";
 220        args[5] = buf.buf;
 221        args[6] = get_object_directory();
 222        args[7] = NULL;
 223
 224        /* NEEDSWORK: handle one level of alternates */
 225        result = run_command(&rsync);
 226
 227        strbuf_release(&buf);
 228
 229        return result;
 230}
 231
 232static int write_one_ref(const char *name, const unsigned char *sha1,
 233                int flags, void *data)
 234{
 235        struct strbuf *buf = data;
 236        int len = buf->len;
 237        FILE *f;
 238
 239        /* when called via for_each_ref(), flags is non-zero */
 240        if (flags && prefixcmp(name, "refs/heads/") &&
 241                        prefixcmp(name, "refs/tags/"))
 242                return 0;
 243
 244        strbuf_addstr(buf, name);
 245        if (safe_create_leading_directories(buf->buf) ||
 246                        !(f = fopen(buf->buf, "w")) ||
 247                        fprintf(f, "%s\n", sha1_to_hex(sha1)) < 0 ||
 248                        fclose(f))
 249                return error("problems writing temporary file %s", buf->buf);
 250        strbuf_setlen(buf, len);
 251        return 0;
 252}
 253
 254static int write_refs_to_temp_dir(struct strbuf *temp_dir,
 255                int refspec_nr, const char **refspec)
 256{
 257        int i;
 258
 259        for (i = 0; i < refspec_nr; i++) {
 260                unsigned char sha1[20];
 261                char *ref;
 262
 263                if (dwim_ref(refspec[i], strlen(refspec[i]), sha1, &ref) != 1)
 264                        return error("Could not get ref %s", refspec[i]);
 265
 266                if (write_one_ref(ref, sha1, 0, temp_dir)) {
 267                        free(ref);
 268                        return -1;
 269                }
 270                free(ref);
 271        }
 272        return 0;
 273}
 274
 275static int rsync_transport_push(struct transport *transport,
 276                int refspec_nr, const char **refspec, int flags)
 277{
 278        struct strbuf buf = STRBUF_INIT, temp_dir = STRBUF_INIT;
 279        int result = 0, i;
 280        struct child_process rsync;
 281        const char *args[10];
 282
 283        if (flags & TRANSPORT_PUSH_MIRROR)
 284                return error("rsync transport does not support mirror mode");
 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 */
 348static int fetch_objs_via_walker(struct transport *transport,
 349                                 int nr_objs, const 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
 376static 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
 385static 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        if (flags & TRANSPORT_PUSH_MIRROR)
 392                return error("http transport does not support mirror mode");
 393
 394        argv = xmalloc((refspec_nr + 12) * sizeof(char *));
 395        argv[0] = "http-push";
 396        argc = 1;
 397        if (flags & TRANSPORT_PUSH_ALL)
 398                argv[argc++] = "--all";
 399        if (flags & TRANSPORT_PUSH_FORCE)
 400                argv[argc++] = "--force";
 401        if (flags & TRANSPORT_PUSH_DRY_RUN)
 402                argv[argc++] = "--dry-run";
 403        if (flags & TRANSPORT_PUSH_VERBOSE)
 404                argv[argc++] = "--verbose";
 405        argv[argc++] = transport->url;
 406        while (refspec_nr--)
 407                argv[argc++] = *refspec++;
 408        argv[argc] = NULL;
 409        err = run_command_v_opt(argv, RUN_GIT_CMD);
 410        switch (err) {
 411        case -ERR_RUN_COMMAND_FORK:
 412                error("unable to fork for %s", argv[0]);
 413        case -ERR_RUN_COMMAND_EXEC:
 414                error("unable to exec %s", argv[0]);
 415                break;
 416        case -ERR_RUN_COMMAND_WAITPID:
 417        case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
 418        case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
 419        case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
 420                error("%s died with strange error", argv[0]);
 421        }
 422        return !!err;
 423}
 424
 425static struct ref *get_refs_via_curl(struct transport *transport)
 426{
 427        struct strbuf buffer = STRBUF_INIT;
 428        char *data, *start, *mid;
 429        char *ref_name;
 430        char *refs_url;
 431        int i = 0;
 432
 433        struct active_request_slot *slot;
 434        struct slot_results results;
 435
 436        struct ref *refs = NULL;
 437        struct ref *ref = NULL;
 438        struct ref *last_ref = NULL;
 439
 440        struct walker *walker;
 441
 442        if (!transport->data)
 443                transport->data = get_http_walker(transport->url,
 444                                                transport->remote);
 445
 446        walker = transport->data;
 447
 448        refs_url = xmalloc(strlen(transport->url) + 11);
 449        sprintf(refs_url, "%s/info/refs", transport->url);
 450
 451        slot = get_active_slot();
 452        slot->results = &results;
 453        curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
 454        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
 455        curl_easy_setopt(slot->curl, CURLOPT_URL, refs_url);
 456        curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, NULL);
 457
 458        if (start_active_slot(slot)) {
 459                run_active_slot(slot);
 460                if (results.curl_result != CURLE_OK) {
 461                        strbuf_release(&buffer);
 462                        if (missing_target(&results))
 463                                die("%s not found: did you run git update-server-info on the server?", refs_url);
 464                        else
 465                                die("%s download error - %s", refs_url, curl_errorstr);
 466                }
 467        } else {
 468                strbuf_release(&buffer);
 469                die("Unable to start HTTP request");
 470        }
 471
 472        data = buffer.buf;
 473        start = NULL;
 474        mid = data;
 475        while (i < buffer.len) {
 476                if (!start)
 477                        start = &data[i];
 478                if (data[i] == '\t')
 479                        mid = &data[i];
 480                if (data[i] == '\n') {
 481                        data[i] = 0;
 482                        ref_name = mid + 1;
 483                        ref = xmalloc(sizeof(struct ref) +
 484                                      strlen(ref_name) + 1);
 485                        memset(ref, 0, sizeof(struct ref));
 486                        strcpy(ref->name, ref_name);
 487                        get_sha1_hex(start, ref->old_sha1);
 488                        if (!refs)
 489                                refs = ref;
 490                        if (last_ref)
 491                                last_ref->next = ref;
 492                        last_ref = ref;
 493                        start = NULL;
 494                }
 495                i++;
 496        }
 497
 498        strbuf_release(&buffer);
 499
 500        ref = alloc_ref("HEAD");
 501        if (!walker->fetch_ref(walker, ref) &&
 502            !resolve_remote_symref(ref, refs)) {
 503                ref->next = refs;
 504                refs = ref;
 505        } else {
 506                free(ref);
 507        }
 508
 509        return refs;
 510}
 511
 512static int fetch_objs_via_curl(struct transport *transport,
 513                                 int nr_objs, const struct ref **to_fetch)
 514{
 515        if (!transport->data)
 516                transport->data = get_http_walker(transport->url,
 517                                                transport->remote);
 518        return fetch_objs_via_walker(transport, nr_objs, to_fetch);
 519}
 520
 521#endif
 522
 523struct bundle_transport_data {
 524        int fd;
 525        struct bundle_header header;
 526};
 527
 528static struct ref *get_refs_from_bundle(struct transport *transport)
 529{
 530        struct bundle_transport_data *data = transport->data;
 531        struct ref *result = NULL;
 532        int i;
 533
 534        if (data->fd > 0)
 535                close(data->fd);
 536        data->fd = read_bundle_header(transport->url, &data->header);
 537        if (data->fd < 0)
 538                die ("Could not read bundle '%s'.", transport->url);
 539        for (i = 0; i < data->header.references.nr; i++) {
 540                struct ref_list_entry *e = data->header.references.list + i;
 541                struct ref *ref = alloc_ref(e->name);
 542                hashcpy(ref->old_sha1, e->sha1);
 543                ref->next = result;
 544                result = ref;
 545        }
 546        return result;
 547}
 548
 549static int fetch_refs_from_bundle(struct transport *transport,
 550                               int nr_heads, const struct ref **to_fetch)
 551{
 552        struct bundle_transport_data *data = transport->data;
 553        return unbundle(&data->header, data->fd);
 554}
 555
 556static int close_bundle(struct transport *transport)
 557{
 558        struct bundle_transport_data *data = transport->data;
 559        if (data->fd > 0)
 560                close(data->fd);
 561        free(data);
 562        return 0;
 563}
 564
 565struct git_transport_data {
 566        unsigned thin : 1;
 567        unsigned keep : 1;
 568        unsigned followtags : 1;
 569        int depth;
 570        struct child_process *conn;
 571        int fd[2];
 572        const char *uploadpack;
 573        const char *receivepack;
 574};
 575
 576static int set_git_option(struct transport *connection,
 577                          const char *name, const char *value)
 578{
 579        struct git_transport_data *data = connection->data;
 580        if (!strcmp(name, TRANS_OPT_UPLOADPACK)) {
 581                data->uploadpack = value;
 582                return 0;
 583        } else if (!strcmp(name, TRANS_OPT_RECEIVEPACK)) {
 584                data->receivepack = value;
 585                return 0;
 586        } else if (!strcmp(name, TRANS_OPT_THIN)) {
 587                data->thin = !!value;
 588                return 0;
 589        } else if (!strcmp(name, TRANS_OPT_FOLLOWTAGS)) {
 590                data->followtags = !!value;
 591                return 0;
 592        } else if (!strcmp(name, TRANS_OPT_KEEP)) {
 593                data->keep = !!value;
 594                return 0;
 595        } else if (!strcmp(name, TRANS_OPT_DEPTH)) {
 596                if (!value)
 597                        data->depth = 0;
 598                else
 599                        data->depth = atoi(value);
 600                return 0;
 601        }
 602        return 1;
 603}
 604
 605static int connect_setup(struct transport *transport)
 606{
 607        struct git_transport_data *data = transport->data;
 608        data->conn = git_connect(data->fd, transport->url, data->uploadpack, 0);
 609        return 0;
 610}
 611
 612static struct ref *get_refs_via_connect(struct transport *transport)
 613{
 614        struct git_transport_data *data = transport->data;
 615        struct ref *refs;
 616
 617        connect_setup(transport);
 618        get_remote_heads(data->fd[0], &refs, 0, NULL, 0, NULL);
 619
 620        return refs;
 621}
 622
 623static int fetch_refs_via_pack(struct transport *transport,
 624                               int nr_heads, const struct ref **to_fetch)
 625{
 626        struct git_transport_data *data = transport->data;
 627        char **heads = xmalloc(nr_heads * sizeof(*heads));
 628        char **origh = xmalloc(nr_heads * sizeof(*origh));
 629        const struct ref *refs;
 630        char *dest = xstrdup(transport->url);
 631        struct fetch_pack_args args;
 632        int i;
 633        struct ref *refs_tmp = NULL;
 634
 635        memset(&args, 0, sizeof(args));
 636        args.uploadpack = data->uploadpack;
 637        args.keep_pack = data->keep;
 638        args.lock_pack = 1;
 639        args.use_thin_pack = data->thin;
 640        args.include_tag = data->followtags;
 641        args.verbose = (transport->verbose > 0);
 642        args.quiet = (transport->verbose < 0);
 643        args.no_progress = args.quiet || (!transport->progress && !isatty(1));
 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
 649        if (!data->conn) {
 650                connect_setup(transport);
 651                get_remote_heads(data->fd[0], &refs_tmp, 0, NULL, 0, NULL);
 652        }
 653
 654        refs = fetch_pack(&args, data->fd, data->conn,
 655                          refs_tmp ? refs_tmp : transport->remote_refs,
 656                          dest, nr_heads, heads, &transport->pack_lockfile);
 657        close(data->fd[0]);
 658        close(data->fd[1]);
 659        if (finish_connect(data->conn))
 660                refs = NULL;
 661        data->conn = NULL;
 662
 663        free_refs(refs_tmp);
 664
 665        for (i = 0; i < nr_heads; i++)
 666                free(origh[i]);
 667        free(origh);
 668        free(heads);
 669        free(dest);
 670        return (refs ? 0 : -1);
 671}
 672
 673static int git_transport_push(struct transport *transport, int refspec_nr, const char **refspec, int flags)
 674{
 675        struct git_transport_data *data = transport->data;
 676        struct send_pack_args args;
 677
 678        args.receivepack = data->receivepack;
 679        args.send_all = !!(flags & TRANSPORT_PUSH_ALL);
 680        args.send_mirror = !!(flags & TRANSPORT_PUSH_MIRROR);
 681        args.force_update = !!(flags & TRANSPORT_PUSH_FORCE);
 682        args.use_thin_pack = data->thin;
 683        args.verbose = !!(flags & TRANSPORT_PUSH_VERBOSE);
 684        args.dry_run = !!(flags & TRANSPORT_PUSH_DRY_RUN);
 685
 686        return send_pack(&args, transport->url, transport->remote, refspec_nr, refspec);
 687}
 688
 689static int disconnect_git(struct transport *transport)
 690{
 691        struct git_transport_data *data = transport->data;
 692        if (data->conn) {
 693                packet_flush(data->fd[1]);
 694                close(data->fd[0]);
 695                close(data->fd[1]);
 696                finish_connect(data->conn);
 697        }
 698
 699        free(data);
 700        return 0;
 701}
 702
 703static int is_local(const char *url)
 704{
 705        const char *colon = strchr(url, ':');
 706        const char *slash = strchr(url, '/');
 707        return !colon || (slash && slash < colon) ||
 708                has_dos_drive_prefix(url);
 709}
 710
 711static int is_file(const char *url)
 712{
 713        struct stat buf;
 714        if (stat(url, &buf))
 715                return 0;
 716        return S_ISREG(buf.st_mode);
 717}
 718
 719struct transport *transport_get(struct remote *remote, const char *url)
 720{
 721        struct transport *ret = xcalloc(1, sizeof(*ret));
 722
 723        ret->remote = remote;
 724        ret->url = url;
 725
 726        if (!prefixcmp(url, "rsync://")) {
 727                ret->get_refs_list = get_refs_via_rsync;
 728                ret->fetch = fetch_objs_via_rsync;
 729                ret->push = rsync_transport_push;
 730
 731        } else if (!prefixcmp(url, "http://")
 732                || !prefixcmp(url, "https://")
 733                || !prefixcmp(url, "ftp://")) {
 734#ifdef NO_CURL
 735                error("git was compiled without libcurl support.");
 736#else
 737                ret->get_refs_list = get_refs_via_curl;
 738                ret->fetch = fetch_objs_via_curl;
 739                ret->push = curl_transport_push;
 740#endif
 741                ret->disconnect = disconnect_walker;
 742
 743        } else if (is_local(url) && is_file(url)) {
 744                struct bundle_transport_data *data = xcalloc(1, sizeof(*data));
 745                ret->data = data;
 746                ret->get_refs_list = get_refs_from_bundle;
 747                ret->fetch = fetch_refs_from_bundle;
 748                ret->disconnect = close_bundle;
 749
 750        } else {
 751                struct git_transport_data *data = xcalloc(1, sizeof(*data));
 752                ret->data = data;
 753                ret->set_option = set_git_option;
 754                ret->get_refs_list = get_refs_via_connect;
 755                ret->fetch = fetch_refs_via_pack;
 756                ret->push = git_transport_push;
 757                ret->disconnect = disconnect_git;
 758
 759                data->thin = 1;
 760                data->conn = NULL;
 761                data->uploadpack = "git-upload-pack";
 762                if (remote && remote->uploadpack)
 763                        data->uploadpack = remote->uploadpack;
 764                data->receivepack = "git-receive-pack";
 765                if (remote && remote->receivepack)
 766                        data->receivepack = remote->receivepack;
 767        }
 768
 769        return ret;
 770}
 771
 772int transport_set_option(struct transport *transport,
 773                         const char *name, const char *value)
 774{
 775        if (transport->set_option)
 776                return transport->set_option(transport, name, value);
 777        return 1;
 778}
 779
 780int transport_push(struct transport *transport,
 781                   int refspec_nr, const char **refspec, int flags)
 782{
 783        if (!transport->push)
 784                return 1;
 785        return transport->push(transport, refspec_nr, refspec, flags);
 786}
 787
 788const struct ref *transport_get_remote_refs(struct transport *transport)
 789{
 790        if (!transport->remote_refs)
 791                transport->remote_refs = transport->get_refs_list(transport);
 792        return transport->remote_refs;
 793}
 794
 795int transport_fetch_refs(struct transport *transport, const struct ref *refs)
 796{
 797        int rc;
 798        int nr_heads = 0, nr_alloc = 0;
 799        const struct ref **heads = NULL;
 800        const struct ref *rm;
 801
 802        for (rm = refs; rm; rm = rm->next) {
 803                if (rm->peer_ref &&
 804                    !hashcmp(rm->peer_ref->old_sha1, rm->old_sha1))
 805                        continue;
 806                ALLOC_GROW(heads, nr_heads + 1, nr_alloc);
 807                heads[nr_heads++] = rm;
 808        }
 809
 810        rc = transport->fetch(transport, nr_heads, heads);
 811        free(heads);
 812        return rc;
 813}
 814
 815void transport_unlock_pack(struct transport *transport)
 816{
 817        if (transport->pack_lockfile) {
 818                unlink(transport->pack_lockfile);
 819                free(transport->pack_lockfile);
 820                transport->pack_lockfile = NULL;
 821        }
 822}
 823
 824int transport_disconnect(struct transport *transport)
 825{
 826        int ret = 0;
 827        if (transport->disconnect)
 828                ret = transport->disconnect(transport);
 829        free(transport);
 830        return ret;
 831}