Andrew's git / gitweb.git / transport.c
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transport.con commit Merge branch 'jc/maint-co-track' into maint (581000a)
   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 (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
 102static 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 (len && 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
 145static 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
 205static int fetch_objs_via_rsync(struct transport *transport,
 206                                int nr_objs, const 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
 236static 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
 258static 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
 279static 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#ifndef NO_CURL /* http fetch is the only user */
 352static int fetch_objs_via_walker(struct transport *transport,
 353                                 int nr_objs, const struct ref **to_fetch)
 354{
 355        char *dest = xstrdup(transport->url);
 356        struct walker *walker = transport->data;
 357        char **objs = xmalloc(nr_objs * sizeof(*objs));
 358        int i;
 359
 360        walker->get_all = 1;
 361        walker->get_tree = 1;
 362        walker->get_history = 1;
 363        walker->get_verbosely = transport->verbose >= 0;
 364        walker->get_recover = 0;
 365
 366        for (i = 0; i < nr_objs; i++)
 367                objs[i] = xstrdup(sha1_to_hex(to_fetch[i]->old_sha1));
 368
 369        if (walker_fetch(walker, nr_objs, objs, NULL, NULL))
 370                die("Fetch failed.");
 371
 372        for (i = 0; i < nr_objs; i++)
 373                free(objs[i]);
 374        free(objs);
 375        free(dest);
 376        return 0;
 377}
 378#endif /* NO_CURL */
 379
 380static int disconnect_walker(struct transport *transport)
 381{
 382        struct walker *walker = transport->data;
 383        if (walker)
 384                walker_free(walker);
 385        return 0;
 386}
 387
 388#ifndef NO_CURL
 389static int curl_transport_push(struct transport *transport, int refspec_nr, const char **refspec, int flags)
 390{
 391        const char **argv;
 392        int argc;
 393        int err;
 394
 395        if (flags & TRANSPORT_PUSH_MIRROR)
 396                return error("http transport does not support mirror mode");
 397
 398        argv = xmalloc((refspec_nr + 12) * sizeof(char *));
 399        argv[0] = "http-push";
 400        argc = 1;
 401        if (flags & TRANSPORT_PUSH_ALL)
 402                argv[argc++] = "--all";
 403        if (flags & TRANSPORT_PUSH_FORCE)
 404                argv[argc++] = "--force";
 405        if (flags & TRANSPORT_PUSH_DRY_RUN)
 406                argv[argc++] = "--dry-run";
 407        if (flags & TRANSPORT_PUSH_VERBOSE)
 408                argv[argc++] = "--verbose";
 409        argv[argc++] = transport->url;
 410        while (refspec_nr--)
 411                argv[argc++] = *refspec++;
 412        argv[argc] = NULL;
 413        err = run_command_v_opt(argv, RUN_GIT_CMD);
 414        switch (err) {
 415        case -ERR_RUN_COMMAND_FORK:
 416                error("unable to fork for %s", argv[0]);
 417        case -ERR_RUN_COMMAND_EXEC:
 418                error("unable to exec %s", argv[0]);
 419                break;
 420        case -ERR_RUN_COMMAND_WAITPID:
 421        case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
 422        case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
 423        case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
 424                error("%s died with strange error", argv[0]);
 425        }
 426        return !!err;
 427}
 428
 429static struct ref *get_refs_via_curl(struct transport *transport)
 430{
 431        struct strbuf buffer = STRBUF_INIT;
 432        char *data, *start, *mid;
 433        char *ref_name;
 434        char *refs_url;
 435        int i = 0;
 436
 437        struct active_request_slot *slot;
 438        struct slot_results results;
 439
 440        struct ref *refs = NULL;
 441        struct ref *ref = NULL;
 442        struct ref *last_ref = NULL;
 443
 444        struct walker *walker;
 445
 446        if (!transport->data)
 447                transport->data = get_http_walker(transport->url,
 448                                                transport->remote);
 449
 450        walker = transport->data;
 451
 452        refs_url = xmalloc(strlen(transport->url) + 11);
 453        sprintf(refs_url, "%s/info/refs", transport->url);
 454
 455        slot = get_active_slot();
 456        slot->results = &results;
 457        curl_easy_setopt(slot->curl, CURLOPT_FILE, &buffer);
 458        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, fwrite_buffer);
 459        curl_easy_setopt(slot->curl, CURLOPT_URL, refs_url);
 460        curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, NULL);
 461
 462        if (start_active_slot(slot)) {
 463                run_active_slot(slot);
 464                if (results.curl_result != CURLE_OK) {
 465                        strbuf_release(&buffer);
 466                        if (missing_target(&results))
 467                                die("%s not found: did you run git update-server-info on the server?", refs_url);
 468                        else
 469                                die("%s download error - %s", refs_url, curl_errorstr);
 470                }
 471        } else {
 472                strbuf_release(&buffer);
 473                die("Unable to start HTTP request");
 474        }
 475
 476        data = buffer.buf;
 477        start = NULL;
 478        mid = data;
 479        while (i < buffer.len) {
 480                if (!start)
 481                        start = &data[i];
 482                if (data[i] == '\t')
 483                        mid = &data[i];
 484                if (data[i] == '\n') {
 485                        data[i] = 0;
 486                        ref_name = mid + 1;
 487                        ref = xmalloc(sizeof(struct ref) +
 488                                      strlen(ref_name) + 1);
 489                        memset(ref, 0, sizeof(struct ref));
 490                        strcpy(ref->name, ref_name);
 491                        get_sha1_hex(start, ref->old_sha1);
 492                        if (!refs)
 493                                refs = ref;
 494                        if (last_ref)
 495                                last_ref->next = ref;
 496                        last_ref = ref;
 497                        start = NULL;
 498                }
 499                i++;
 500        }
 501
 502        strbuf_release(&buffer);
 503
 504        ref = alloc_ref_from_str("HEAD");
 505        if (!walker->fetch_ref(walker, ref) &&
 506            !resolve_remote_symref(ref, refs)) {
 507                ref->next = refs;
 508                refs = ref;
 509        } else {
 510                free(ref);
 511        }
 512
 513        return refs;
 514}
 515
 516static int fetch_objs_via_curl(struct transport *transport,
 517                                 int nr_objs, const struct ref **to_fetch)
 518{
 519        if (!transport->data)
 520                transport->data = get_http_walker(transport->url,
 521                                                transport->remote);
 522        return fetch_objs_via_walker(transport, nr_objs, to_fetch);
 523}
 524
 525#endif
 526
 527struct bundle_transport_data {
 528        int fd;
 529        struct bundle_header header;
 530};
 531
 532static struct ref *get_refs_from_bundle(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_from_str(e->name);
 546                hashcpy(ref->old_sha1, e->sha1);
 547                ref->next = result;
 548                result = ref;
 549        }
 550        return result;
 551}
 552
 553static int fetch_refs_from_bundle(struct transport *transport,
 554                               int nr_heads, const struct ref **to_fetch)
 555{
 556        struct bundle_transport_data *data = transport->data;
 557        return unbundle(&data->header, data->fd);
 558}
 559
 560static int close_bundle(struct transport *transport)
 561{
 562        struct bundle_transport_data *data = transport->data;
 563        if (data->fd > 0)
 564                close(data->fd);
 565        free(data);
 566        return 0;
 567}
 568
 569struct git_transport_data {
 570        unsigned thin : 1;
 571        unsigned keep : 1;
 572        unsigned followtags : 1;
 573        int depth;
 574        struct child_process *conn;
 575        int fd[2];
 576        const char *uploadpack;
 577        const char *receivepack;
 578};
 579
 580static int set_git_option(struct transport *connection,
 581                          const char *name, const char *value)
 582{
 583        struct git_transport_data *data = connection->data;
 584        if (!strcmp(name, TRANS_OPT_UPLOADPACK)) {
 585                data->uploadpack = value;
 586                return 0;
 587        } else if (!strcmp(name, TRANS_OPT_RECEIVEPACK)) {
 588                data->receivepack = value;
 589                return 0;
 590        } else if (!strcmp(name, TRANS_OPT_THIN)) {
 591                data->thin = !!value;
 592                return 0;
 593        } else if (!strcmp(name, TRANS_OPT_FOLLOWTAGS)) {
 594                data->followtags = !!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
 609static int connect_setup(struct transport *transport)
 610{
 611        struct git_transport_data *data = transport->data;
 612        data->conn = git_connect(data->fd, transport->url, data->uploadpack, 0);
 613        return 0;
 614}
 615
 616static struct ref *get_refs_via_connect(struct transport *transport)
 617{
 618        struct git_transport_data *data = transport->data;
 619        struct ref *refs;
 620
 621        connect_setup(transport);
 622        get_remote_heads(data->fd[0], &refs, 0, NULL, 0);
 623
 624        return refs;
 625}
 626
 627static int fetch_refs_via_pack(struct transport *transport,
 628                               int nr_heads, const 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        const struct ref *refs;
 634        char *dest = xstrdup(transport->url);
 635        struct fetch_pack_args args;
 636        int i;
 637        struct ref *refs_tmp = NULL;
 638
 639        memset(&args, 0, sizeof(args));
 640        args.uploadpack = data->uploadpack;
 641        args.keep_pack = data->keep;
 642        args.lock_pack = 1;
 643        args.use_thin_pack = data->thin;
 644        args.include_tag = data->followtags;
 645        args.verbose = (transport->verbose > 0);
 646        args.quiet = (transport->verbose < 0);
 647        args.no_progress = args.quiet || !isatty(1);
 648        args.depth = data->depth;
 649
 650        for (i = 0; i < nr_heads; i++)
 651                origh[i] = heads[i] = xstrdup(to_fetch[i]->name);
 652
 653        if (!data->conn) {
 654                connect_setup(transport);
 655                get_remote_heads(data->fd[0], &refs_tmp, 0, NULL, 0);
 656        }
 657
 658        refs = fetch_pack(&args, data->fd, data->conn,
 659                          refs_tmp ? refs_tmp : transport->remote_refs,
 660                          dest, nr_heads, heads, &transport->pack_lockfile);
 661        close(data->fd[0]);
 662        close(data->fd[1]);
 663        if (finish_connect(data->conn))
 664                refs = NULL;
 665        data->conn = NULL;
 666
 667        free_refs(refs_tmp);
 668
 669        for (i = 0; i < nr_heads; i++)
 670                free(origh[i]);
 671        free(origh);
 672        free(heads);
 673        free(dest);
 674        return (refs ? 0 : -1);
 675}
 676
 677static int git_transport_push(struct transport *transport, int refspec_nr, const char **refspec, int flags)
 678{
 679        struct git_transport_data *data = transport->data;
 680        struct send_pack_args args;
 681
 682        args.receivepack = data->receivepack;
 683        args.send_all = !!(flags & TRANSPORT_PUSH_ALL);
 684        args.send_mirror = !!(flags & TRANSPORT_PUSH_MIRROR);
 685        args.force_update = !!(flags & TRANSPORT_PUSH_FORCE);
 686        args.use_thin_pack = data->thin;
 687        args.verbose = !!(flags & TRANSPORT_PUSH_VERBOSE);
 688        args.dry_run = !!(flags & TRANSPORT_PUSH_DRY_RUN);
 689
 690        return send_pack(&args, transport->url, transport->remote, refspec_nr, refspec);
 691}
 692
 693static int disconnect_git(struct transport *transport)
 694{
 695        struct git_transport_data *data = transport->data;
 696        if (data->conn) {
 697                packet_flush(data->fd[1]);
 698                close(data->fd[0]);
 699                close(data->fd[1]);
 700                finish_connect(data->conn);
 701        }
 702
 703        free(data);
 704        return 0;
 705}
 706
 707static int is_local(const char *url)
 708{
 709        const char *colon = strchr(url, ':');
 710        const char *slash = strchr(url, '/');
 711        return !colon || (slash && slash < colon) ||
 712                has_dos_drive_prefix(url);
 713}
 714
 715static int is_file(const char *url)
 716{
 717        struct stat buf;
 718        if (stat(url, &buf))
 719                return 0;
 720        return S_ISREG(buf.st_mode);
 721}
 722
 723struct transport *transport_get(struct remote *remote, const char *url)
 724{
 725        struct transport *ret = xcalloc(1, sizeof(*ret));
 726
 727        ret->remote = remote;
 728        ret->url = url;
 729
 730        if (!prefixcmp(url, "rsync://")) {
 731                ret->get_refs_list = get_refs_via_rsync;
 732                ret->fetch = fetch_objs_via_rsync;
 733                ret->push = rsync_transport_push;
 734
 735        } else if (!prefixcmp(url, "http://")
 736                || !prefixcmp(url, "https://")
 737                || !prefixcmp(url, "ftp://")) {
 738#ifdef NO_CURL
 739                error("git was compiled without libcurl support.");
 740#else
 741                ret->get_refs_list = get_refs_via_curl;
 742                ret->fetch = fetch_objs_via_curl;
 743                ret->push = curl_transport_push;
 744#endif
 745                ret->disconnect = disconnect_walker;
 746
 747        } else if (is_local(url) && is_file(url)) {
 748                struct bundle_transport_data *data = xcalloc(1, sizeof(*data));
 749                ret->data = data;
 750                ret->get_refs_list = get_refs_from_bundle;
 751                ret->fetch = fetch_refs_from_bundle;
 752                ret->disconnect = close_bundle;
 753
 754        } else {
 755                struct git_transport_data *data = xcalloc(1, sizeof(*data));
 756                ret->data = data;
 757                ret->set_option = set_git_option;
 758                ret->get_refs_list = get_refs_via_connect;
 759                ret->fetch = fetch_refs_via_pack;
 760                ret->push = git_transport_push;
 761                ret->disconnect = disconnect_git;
 762
 763                data->thin = 1;
 764                data->conn = NULL;
 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
 776int 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
 784int 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
 792const 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
 799int transport_fetch_refs(struct transport *transport, const struct ref *refs)
 800{
 801        int rc;
 802        int nr_heads = 0, nr_alloc = 0;
 803        const struct ref **heads = NULL;
 804        const 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
 819void 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
 828int 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}