Andrew's git / gitweb.git / transport-helper.c
?
transport-helper.con commit git-am: Add am.keepcr and --no-keep-cr to override it (e80d4cb)
   1#include "cache.h"
   2#include "transport.h"
   3#include "quote.h"
   4#include "run-command.h"
   5#include "commit.h"
   6#include "diff.h"
   7#include "revision.h"
   8#include "quote.h"
   9#include "remote.h"
  10
  11static int debug;
  12
  13struct helper_data
  14{
  15        const char *name;
  16        struct child_process *helper;
  17        FILE *out;
  18        unsigned fetch : 1,
  19                import : 1,
  20                option : 1,
  21                push : 1,
  22                connect : 1,
  23                no_disconnect_req : 1;
  24        /* These go from remote name (as in "list") to private name */
  25        struct refspec *refspecs;
  26        int refspec_nr;
  27        /* Transport options for fetch-pack/send-pack (should one of
  28         * those be invoked).
  29         */
  30        struct git_transport_options transport_options;
  31};
  32
  33static void sendline(struct helper_data *helper, struct strbuf *buffer)
  34{
  35        if (debug)
  36                fprintf(stderr, "Debug: Remote helper: -> %s", buffer->buf);
  37        if (write_in_full(helper->helper->in, buffer->buf, buffer->len)
  38                != buffer->len)
  39                die_errno("Full write to remote helper failed");
  40}
  41
  42static int recvline_fh(FILE *helper, struct strbuf *buffer)
  43{
  44        strbuf_reset(buffer);
  45        if (debug)
  46                fprintf(stderr, "Debug: Remote helper: Waiting...\n");
  47        if (strbuf_getline(buffer, helper, '\n') == EOF) {
  48                if (debug)
  49                        fprintf(stderr, "Debug: Remote helper quit.\n");
  50                exit(128);
  51        }
  52
  53        if (debug)
  54                fprintf(stderr, "Debug: Remote helper: <- %s\n", buffer->buf);
  55        return 0;
  56}
  57
  58static int recvline(struct helper_data *helper, struct strbuf *buffer)
  59{
  60        return recvline_fh(helper->out, buffer);
  61}
  62
  63static void xchgline(struct helper_data *helper, struct strbuf *buffer)
  64{
  65        sendline(helper, buffer);
  66        recvline(helper, buffer);
  67}
  68
  69static void write_constant(int fd, const char *str)
  70{
  71        if (debug)
  72                fprintf(stderr, "Debug: Remote helper: -> %s", str);
  73        if (write_in_full(fd, str, strlen(str)) != strlen(str))
  74                die_errno("Full write to remote helper failed");
  75}
  76
  77const char *remove_ext_force(const char *url)
  78{
  79        if (url) {
  80                const char *colon = strchr(url, ':');
  81                if (colon && colon[1] == ':')
  82                        return colon + 2;
  83        }
  84        return url;
  85}
  86
  87static void do_take_over(struct transport *transport)
  88{
  89        struct helper_data *data;
  90        data = (struct helper_data *)transport->data;
  91        transport_take_over(transport, data->helper);
  92        fclose(data->out);
  93        free(data);
  94}
  95
  96static struct child_process *get_helper(struct transport *transport)
  97{
  98        struct helper_data *data = transport->data;
  99        struct strbuf buf = STRBUF_INIT;
 100        struct child_process *helper;
 101        const char **refspecs = NULL;
 102        int refspec_nr = 0;
 103        int refspec_alloc = 0;
 104        int duped;
 105        int code;
 106
 107        if (data->helper)
 108                return data->helper;
 109
 110        helper = xcalloc(1, sizeof(*helper));
 111        helper->in = -1;
 112        helper->out = -1;
 113        helper->err = 0;
 114        helper->argv = xcalloc(4, sizeof(*helper->argv));
 115        strbuf_addf(&buf, "git-remote-%s", data->name);
 116        helper->argv[0] = strbuf_detach(&buf, NULL);
 117        helper->argv[1] = transport->remote->name;
 118        helper->argv[2] = remove_ext_force(transport->url);
 119        helper->git_cmd = 0;
 120        helper->silent_exec_failure = 1;
 121        code = start_command(helper);
 122        if (code < 0 && errno == ENOENT)
 123                die("Unable to find remote helper for '%s'", data->name);
 124        else if (code != 0)
 125                exit(code);
 126
 127        data->helper = helper;
 128        data->no_disconnect_req = 0;
 129
 130        /*
 131         * Open the output as FILE* so strbuf_getline() can be used.
 132         * Do this with duped fd because fclose() will close the fd,
 133         * and stuff like taking over will require the fd to remain.
 134         */
 135        duped = dup(helper->out);
 136        if (duped < 0)
 137                die_errno("Can't dup helper output fd");
 138        data->out = xfdopen(duped, "r");
 139
 140        write_constant(helper->in, "capabilities\n");
 141
 142        while (1) {
 143                const char *capname;
 144                int mandatory = 0;
 145                recvline(data, &buf);
 146
 147                if (!*buf.buf)
 148                        break;
 149
 150                if (*buf.buf == '*') {
 151                        capname = buf.buf + 1;
 152                        mandatory = 1;
 153                } else
 154                        capname = buf.buf;
 155
 156                if (debug)
 157                        fprintf(stderr, "Debug: Got cap %s\n", capname);
 158                if (!strcmp(capname, "fetch"))
 159                        data->fetch = 1;
 160                else if (!strcmp(capname, "option"))
 161                        data->option = 1;
 162                else if (!strcmp(capname, "push"))
 163                        data->push = 1;
 164                else if (!strcmp(capname, "import"))
 165                        data->import = 1;
 166                else if (!data->refspecs && !prefixcmp(capname, "refspec ")) {
 167                        ALLOC_GROW(refspecs,
 168                                   refspec_nr + 1,
 169                                   refspec_alloc);
 170                        refspecs[refspec_nr++] = strdup(buf.buf + strlen("refspec "));
 171                } else if (!strcmp(capname, "connect")) {
 172                        data->connect = 1;
 173                } else if (mandatory) {
 174                        die("Unknown mandatory capability %s. This remote "
 175                            "helper probably needs newer version of Git.\n",
 176                            capname);
 177                }
 178        }
 179        if (refspecs) {
 180                int i;
 181                data->refspec_nr = refspec_nr;
 182                data->refspecs = parse_fetch_refspec(refspec_nr, refspecs);
 183                for (i = 0; i < refspec_nr; i++) {
 184                        free((char *)refspecs[i]);
 185                }
 186                free(refspecs);
 187        }
 188        strbuf_release(&buf);
 189        if (debug)
 190                fprintf(stderr, "Debug: Capabilities complete.\n");
 191        return data->helper;
 192}
 193
 194static int disconnect_helper(struct transport *transport)
 195{
 196        struct helper_data *data = transport->data;
 197        struct strbuf buf = STRBUF_INIT;
 198
 199        if (data->helper) {
 200                if (debug)
 201                        fprintf(stderr, "Debug: Disconnecting.\n");
 202                if (!data->no_disconnect_req) {
 203                        strbuf_addf(&buf, "\n");
 204                        sendline(data, &buf);
 205                }
 206                close(data->helper->in);
 207                close(data->helper->out);
 208                fclose(data->out);
 209                finish_command(data->helper);
 210                free((char *)data->helper->argv[0]);
 211                free(data->helper->argv);
 212                free(data->helper);
 213                data->helper = NULL;
 214        }
 215        return 0;
 216}
 217
 218static const char *unsupported_options[] = {
 219        TRANS_OPT_UPLOADPACK,
 220        TRANS_OPT_RECEIVEPACK,
 221        TRANS_OPT_THIN,
 222        TRANS_OPT_KEEP
 223        };
 224static const char *boolean_options[] = {
 225        TRANS_OPT_THIN,
 226        TRANS_OPT_KEEP,
 227        TRANS_OPT_FOLLOWTAGS
 228        };
 229
 230static int set_helper_option(struct transport *transport,
 231                          const char *name, const char *value)
 232{
 233        struct helper_data *data = transport->data;
 234        struct strbuf buf = STRBUF_INIT;
 235        int i, ret, is_bool = 0;
 236
 237        get_helper(transport);
 238
 239        if (!data->option)
 240                return 1;
 241
 242        for (i = 0; i < ARRAY_SIZE(unsupported_options); i++) {
 243                if (!strcmp(name, unsupported_options[i]))
 244                        return 1;
 245        }
 246
 247        for (i = 0; i < ARRAY_SIZE(boolean_options); i++) {
 248                if (!strcmp(name, boolean_options[i])) {
 249                        is_bool = 1;
 250                        break;
 251                }
 252        }
 253
 254        strbuf_addf(&buf, "option %s ", name);
 255        if (is_bool)
 256                strbuf_addstr(&buf, value ? "true" : "false");
 257        else
 258                quote_c_style(value, &buf, NULL, 0);
 259        strbuf_addch(&buf, '\n');
 260
 261        xchgline(data, &buf);
 262
 263        if (!strcmp(buf.buf, "ok"))
 264                ret = 0;
 265        else if (!prefixcmp(buf.buf, "error")) {
 266                ret = -1;
 267        } else if (!strcmp(buf.buf, "unsupported"))
 268                ret = 1;
 269        else {
 270                warning("%s unexpectedly said: '%s'", data->name, buf.buf);
 271                ret = 1;
 272        }
 273        strbuf_release(&buf);
 274        return ret;
 275}
 276
 277static void standard_options(struct transport *t)
 278{
 279        char buf[16];
 280        int n;
 281        int v = t->verbose;
 282        int no_progress = v < 0 || (!t->progress && !isatty(2));
 283
 284        set_helper_option(t, "progress", !no_progress ? "true" : "false");
 285
 286        n = snprintf(buf, sizeof(buf), "%d", v + 1);
 287        if (n >= sizeof(buf))
 288                die("impossibly large verbosity value");
 289        set_helper_option(t, "verbosity", buf);
 290}
 291
 292static int release_helper(struct transport *transport)
 293{
 294        struct helper_data *data = transport->data;
 295        free_refspec(data->refspec_nr, data->refspecs);
 296        data->refspecs = NULL;
 297        disconnect_helper(transport);
 298        free(transport->data);
 299        return 0;
 300}
 301
 302static int fetch_with_fetch(struct transport *transport,
 303                            int nr_heads, struct ref **to_fetch)
 304{
 305        struct helper_data *data = transport->data;
 306        int i;
 307        struct strbuf buf = STRBUF_INIT;
 308
 309        standard_options(transport);
 310
 311        for (i = 0; i < nr_heads; i++) {
 312                const struct ref *posn = to_fetch[i];
 313                if (posn->status & REF_STATUS_UPTODATE)
 314                        continue;
 315
 316                strbuf_addf(&buf, "fetch %s %s\n",
 317                            sha1_to_hex(posn->old_sha1), posn->name);
 318        }
 319
 320        strbuf_addch(&buf, '\n');
 321        sendline(data, &buf);
 322
 323        while (1) {
 324                recvline(data, &buf);
 325
 326                if (!prefixcmp(buf.buf, "lock ")) {
 327                        const char *name = buf.buf + 5;
 328                        if (transport->pack_lockfile)
 329                                warning("%s also locked %s", data->name, name);
 330                        else
 331                                transport->pack_lockfile = xstrdup(name);
 332                }
 333                else if (!buf.len)
 334                        break;
 335                else
 336                        warning("%s unexpectedly said: '%s'", data->name, buf.buf);
 337        }
 338        strbuf_release(&buf);
 339        return 0;
 340}
 341
 342static int get_importer(struct transport *transport, struct child_process *fastimport)
 343{
 344        struct child_process *helper = get_helper(transport);
 345        memset(fastimport, 0, sizeof(*fastimport));
 346        fastimport->in = helper->out;
 347        fastimport->argv = xcalloc(5, sizeof(*fastimport->argv));
 348        fastimport->argv[0] = "fast-import";
 349        fastimport->argv[1] = "--quiet";
 350
 351        fastimport->git_cmd = 1;
 352        return start_command(fastimport);
 353}
 354
 355static int fetch_with_import(struct transport *transport,
 356                             int nr_heads, struct ref **to_fetch)
 357{
 358        struct child_process fastimport;
 359        struct helper_data *data = transport->data;
 360        int i;
 361        struct ref *posn;
 362        struct strbuf buf = STRBUF_INIT;
 363
 364        get_helper(transport);
 365
 366        if (get_importer(transport, &fastimport))
 367                die("Couldn't run fast-import");
 368
 369        for (i = 0; i < nr_heads; i++) {
 370                posn = to_fetch[i];
 371                if (posn->status & REF_STATUS_UPTODATE)
 372                        continue;
 373
 374                strbuf_addf(&buf, "import %s\n", posn->name);
 375                sendline(data, &buf);
 376                strbuf_reset(&buf);
 377        }
 378        disconnect_helper(transport);
 379        finish_command(&fastimport);
 380        free(fastimport.argv);
 381        fastimport.argv = NULL;
 382
 383        for (i = 0; i < nr_heads; i++) {
 384                char *private;
 385                posn = to_fetch[i];
 386                if (posn->status & REF_STATUS_UPTODATE)
 387                        continue;
 388                if (data->refspecs)
 389                        private = apply_refspecs(data->refspecs, data->refspec_nr, posn->name);
 390                else
 391                        private = strdup(posn->name);
 392                read_ref(private, posn->old_sha1);
 393                free(private);
 394        }
 395        strbuf_release(&buf);
 396        return 0;
 397}
 398
 399static int process_connect_service(struct transport *transport,
 400                                   const char *name, const char *exec)
 401{
 402        struct helper_data *data = transport->data;
 403        struct strbuf cmdbuf = STRBUF_INIT;
 404        struct child_process *helper;
 405        int r, duped, ret = 0;
 406        FILE *input;
 407
 408        helper = get_helper(transport);
 409
 410        /*
 411         * Yes, dup the pipe another time, as we need unbuffered version
 412         * of input pipe as FILE*. fclose() closes the underlying fd and
 413         * stream buffering only can be changed before first I/O operation
 414         * on it.
 415         */
 416        duped = dup(helper->out);
 417        if (duped < 0)
 418                die_errno("Can't dup helper output fd");
 419        input = xfdopen(duped, "r");
 420        setvbuf(input, NULL, _IONBF, 0);
 421
 422        /*
 423         * Handle --upload-pack and friends. This is fire and forget...
 424         * just warn if it fails.
 425         */
 426        if (strcmp(name, exec)) {
 427                r = set_helper_option(transport, "servpath", exec);
 428                if (r > 0)
 429                        warning("Setting remote service path not supported by protocol.");
 430                else if (r < 0)
 431                        warning("Invalid remote service path.");
 432        }
 433
 434        if (data->connect)
 435                strbuf_addf(&cmdbuf, "connect %s\n", name);
 436        else
 437                goto exit;
 438
 439        sendline(data, &cmdbuf);
 440        recvline_fh(input, &cmdbuf);
 441        if (!strcmp(cmdbuf.buf, "")) {
 442                data->no_disconnect_req = 1;
 443                if (debug)
 444                        fprintf(stderr, "Debug: Smart transport connection "
 445                                "ready.\n");
 446                ret = 1;
 447        } else if (!strcmp(cmdbuf.buf, "fallback")) {
 448                if (debug)
 449                        fprintf(stderr, "Debug: Falling back to dumb "
 450                                "transport.\n");
 451        } else
 452                die("Unknown response to connect: %s",
 453                        cmdbuf.buf);
 454
 455exit:
 456        fclose(input);
 457        return ret;
 458}
 459
 460static int process_connect(struct transport *transport,
 461                                     int for_push)
 462{
 463        struct helper_data *data = transport->data;
 464        const char *name;
 465        const char *exec;
 466
 467        name = for_push ? "git-receive-pack" : "git-upload-pack";
 468        if (for_push)
 469                exec = data->transport_options.receivepack;
 470        else
 471                exec = data->transport_options.uploadpack;
 472
 473        return process_connect_service(transport, name, exec);
 474}
 475
 476static int connect_helper(struct transport *transport, const char *name,
 477                   const char *exec, int fd[2])
 478{
 479        struct helper_data *data = transport->data;
 480
 481        /* Get_helper so connect is inited. */
 482        get_helper(transport);
 483        if (!data->connect)
 484                die("Operation not supported by protocol.");
 485
 486        if (!process_connect_service(transport, name, exec))
 487                die("Can't connect to subservice %s.", name);
 488
 489        fd[0] = data->helper->out;
 490        fd[1] = data->helper->in;
 491        return 0;
 492}
 493
 494static int fetch(struct transport *transport,
 495                 int nr_heads, struct ref **to_fetch)
 496{
 497        struct helper_data *data = transport->data;
 498        int i, count;
 499
 500        if (process_connect(transport, 0)) {
 501                do_take_over(transport);
 502                return transport->fetch(transport, nr_heads, to_fetch);
 503        }
 504
 505        count = 0;
 506        for (i = 0; i < nr_heads; i++)
 507                if (!(to_fetch[i]->status & REF_STATUS_UPTODATE))
 508                        count++;
 509
 510        if (!count)
 511                return 0;
 512
 513        if (data->fetch)
 514                return fetch_with_fetch(transport, nr_heads, to_fetch);
 515
 516        if (data->import)
 517                return fetch_with_import(transport, nr_heads, to_fetch);
 518
 519        return -1;
 520}
 521
 522static int push_refs(struct transport *transport,
 523                struct ref *remote_refs, int flags)
 524{
 525        int force_all = flags & TRANSPORT_PUSH_FORCE;
 526        int mirror = flags & TRANSPORT_PUSH_MIRROR;
 527        struct helper_data *data = transport->data;
 528        struct strbuf buf = STRBUF_INIT;
 529        struct child_process *helper;
 530        struct ref *ref;
 531
 532        if (process_connect(transport, 1)) {
 533                do_take_over(transport);
 534                return transport->push_refs(transport, remote_refs, flags);
 535        }
 536
 537        if (!remote_refs) {
 538                fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
 539                        "Perhaps you should specify a branch such as 'master'.\n");
 540                return 0;
 541        }
 542
 543        helper = get_helper(transport);
 544        if (!data->push)
 545                return 1;
 546
 547        for (ref = remote_refs; ref; ref = ref->next) {
 548                if (!ref->peer_ref && !mirror)
 549                        continue;
 550
 551                /* Check for statuses set by set_ref_status_for_push() */
 552                switch (ref->status) {
 553                case REF_STATUS_REJECT_NONFASTFORWARD:
 554                case REF_STATUS_UPTODATE:
 555                        continue;
 556                default:
 557                        ; /* do nothing */
 558                }
 559
 560                if (force_all)
 561                        ref->force = 1;
 562
 563                strbuf_addstr(&buf, "push ");
 564                if (!ref->deletion) {
 565                        if (ref->force)
 566                                strbuf_addch(&buf, '+');
 567                        if (ref->peer_ref)
 568                                strbuf_addstr(&buf, ref->peer_ref->name);
 569                        else
 570                                strbuf_addstr(&buf, sha1_to_hex(ref->new_sha1));
 571                }
 572                strbuf_addch(&buf, ':');
 573                strbuf_addstr(&buf, ref->name);
 574                strbuf_addch(&buf, '\n');
 575        }
 576        if (buf.len == 0)
 577                return 0;
 578
 579        transport->verbose = flags & TRANSPORT_PUSH_VERBOSE ? 1 : 0;
 580        standard_options(transport);
 581
 582        if (flags & TRANSPORT_PUSH_DRY_RUN) {
 583                if (set_helper_option(transport, "dry-run", "true") != 0)
 584                        die("helper %s does not support dry-run", data->name);
 585        }
 586
 587        strbuf_addch(&buf, '\n');
 588        sendline(data, &buf);
 589
 590        ref = remote_refs;
 591        while (1) {
 592                char *refname, *msg;
 593                int status;
 594
 595                recvline(data, &buf);
 596                if (!buf.len)
 597                        break;
 598
 599                if (!prefixcmp(buf.buf, "ok ")) {
 600                        status = REF_STATUS_OK;
 601                        refname = buf.buf + 3;
 602                } else if (!prefixcmp(buf.buf, "error ")) {
 603                        status = REF_STATUS_REMOTE_REJECT;
 604                        refname = buf.buf + 6;
 605                } else
 606                        die("expected ok/error, helper said '%s'\n", buf.buf);
 607
 608                msg = strchr(refname, ' ');
 609                if (msg) {
 610                        struct strbuf msg_buf = STRBUF_INIT;
 611                        const char *end;
 612
 613                        *msg++ = '\0';
 614                        if (!unquote_c_style(&msg_buf, msg, &end))
 615                                msg = strbuf_detach(&msg_buf, NULL);
 616                        else
 617                                msg = xstrdup(msg);
 618                        strbuf_release(&msg_buf);
 619
 620                        if (!strcmp(msg, "no match")) {
 621                                status = REF_STATUS_NONE;
 622                                free(msg);
 623                                msg = NULL;
 624                        }
 625                        else if (!strcmp(msg, "up to date")) {
 626                                status = REF_STATUS_UPTODATE;
 627                                free(msg);
 628                                msg = NULL;
 629                        }
 630                        else if (!strcmp(msg, "non-fast forward")) {
 631                                status = REF_STATUS_REJECT_NONFASTFORWARD;
 632                                free(msg);
 633                                msg = NULL;
 634                        }
 635                }
 636
 637                if (ref)
 638                        ref = find_ref_by_name(ref, refname);
 639                if (!ref)
 640                        ref = find_ref_by_name(remote_refs, refname);
 641                if (!ref) {
 642                        warning("helper reported unexpected status of %s", refname);
 643                        continue;
 644                }
 645
 646                if (ref->status != REF_STATUS_NONE) {
 647                        /*
 648                         * Earlier, the ref was marked not to be pushed, so ignore the ref
 649                         * status reported by the remote helper if the latter is 'no match'.
 650                         */
 651                        if (status == REF_STATUS_NONE)
 652                                continue;
 653                }
 654
 655                ref->status = status;
 656                ref->remote_status = msg;
 657        }
 658        strbuf_release(&buf);
 659        return 0;
 660}
 661
 662static int has_attribute(const char *attrs, const char *attr) {
 663        int len;
 664        if (!attrs)
 665                return 0;
 666
 667        len = strlen(attr);
 668        for (;;) {
 669                const char *space = strchrnul(attrs, ' ');
 670                if (len == space - attrs && !strncmp(attrs, attr, len))
 671                        return 1;
 672                if (!*space)
 673                        return 0;
 674                attrs = space + 1;
 675        }
 676}
 677
 678static struct ref *get_refs_list(struct transport *transport, int for_push)
 679{
 680        struct helper_data *data = transport->data;
 681        struct child_process *helper;
 682        struct ref *ret = NULL;
 683        struct ref **tail = &ret;
 684        struct ref *posn;
 685        struct strbuf buf = STRBUF_INIT;
 686
 687        helper = get_helper(transport);
 688
 689        if (process_connect(transport, for_push)) {
 690                do_take_over(transport);
 691                return transport->get_refs_list(transport, for_push);
 692        }
 693
 694        if (data->push && for_push)
 695                write_str_in_full(helper->in, "list for-push\n");
 696        else
 697                write_str_in_full(helper->in, "list\n");
 698
 699        while (1) {
 700                char *eov, *eon;
 701                recvline(data, &buf);
 702
 703                if (!*buf.buf)
 704                        break;
 705
 706                eov = strchr(buf.buf, ' ');
 707                if (!eov)
 708                        die("Malformed response in ref list: %s", buf.buf);
 709                eon = strchr(eov + 1, ' ');
 710                *eov = '\0';
 711                if (eon)
 712                        *eon = '\0';
 713                *tail = alloc_ref(eov + 1);
 714                if (buf.buf[0] == '@')
 715                        (*tail)->symref = xstrdup(buf.buf + 1);
 716                else if (buf.buf[0] != '?')
 717                        get_sha1_hex(buf.buf, (*tail)->old_sha1);
 718                if (eon) {
 719                        if (has_attribute(eon + 1, "unchanged")) {
 720                                (*tail)->status |= REF_STATUS_UPTODATE;
 721                                read_ref((*tail)->name, (*tail)->old_sha1);
 722                        }
 723                }
 724                tail = &((*tail)->next);
 725        }
 726        if (debug)
 727                fprintf(stderr, "Debug: Read ref listing.\n");
 728        strbuf_release(&buf);
 729
 730        for (posn = ret; posn; posn = posn->next)
 731                resolve_remote_symref(posn, ret);
 732
 733        return ret;
 734}
 735
 736int transport_helper_init(struct transport *transport, const char *name)
 737{
 738        struct helper_data *data = xcalloc(sizeof(*data), 1);
 739        data->name = name;
 740
 741        if (getenv("GIT_TRANSPORT_HELPER_DEBUG"))
 742                debug = 1;
 743
 744        transport->data = data;
 745        transport->set_option = set_helper_option;
 746        transport->get_refs_list = get_refs_list;
 747        transport->fetch = fetch;
 748        transport->push_refs = push_refs;
 749        transport->disconnect = release_helper;
 750        transport->connect = connect_helper;
 751        transport->smart_options = &(data->transport_options);
 752        return 0;
 753}