cec83bd663d0f27589bd09176e38b084270f56c4
   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 "remote.h"
   9#include "string-list.h"
  10#include "thread-utils.h"
  11#include "sigchain.h"
  12#include "argv-array.h"
  13#include "refs.h"
  14#include "refspec.h"
  15#include "transport-internal.h"
  16#include "protocol.h"
  17
  18static int debug;
  19
  20struct helper_data {
  21        const char *name;
  22        struct child_process *helper;
  23        FILE *out;
  24        unsigned fetch : 1,
  25                import : 1,
  26                bidi_import : 1,
  27                export : 1,
  28                option : 1,
  29                push : 1,
  30                connect : 1,
  31                stateless_connect : 1,
  32                signed_tags : 1,
  33                check_connectivity : 1,
  34                no_disconnect_req : 1,
  35                no_private_update : 1;
  36        char *export_marks;
  37        char *import_marks;
  38        /* These go from remote name (as in "list") to private name */
  39        struct refspec rs;
  40        /* Transport options for fetch-pack/send-pack (should one of
  41         * those be invoked).
  42         */
  43        struct git_transport_options transport_options;
  44};
  45
  46static void sendline(struct helper_data *helper, struct strbuf *buffer)
  47{
  48        if (debug)
  49                fprintf(stderr, "Debug: Remote helper: -> %s", buffer->buf);
  50        if (write_in_full(helper->helper->in, buffer->buf, buffer->len) < 0)
  51                die_errno(_("full write to remote helper failed"));
  52}
  53
  54static int recvline_fh(FILE *helper, struct strbuf *buffer)
  55{
  56        strbuf_reset(buffer);
  57        if (debug)
  58                fprintf(stderr, "Debug: Remote helper: Waiting...\n");
  59        if (strbuf_getline(buffer, helper) == EOF) {
  60                if (debug)
  61                        fprintf(stderr, "Debug: Remote helper quit.\n");
  62                return 1;
  63        }
  64
  65        if (debug)
  66                fprintf(stderr, "Debug: Remote helper: <- %s\n", buffer->buf);
  67        return 0;
  68}
  69
  70static int recvline(struct helper_data *helper, struct strbuf *buffer)
  71{
  72        return recvline_fh(helper->out, buffer);
  73}
  74
  75static void write_constant(int fd, const char *str)
  76{
  77        if (debug)
  78                fprintf(stderr, "Debug: Remote helper: -> %s", str);
  79        if (write_in_full(fd, str, strlen(str)) < 0)
  80                die_errno(_("full write to remote helper failed"));
  81}
  82
  83static const char *remove_ext_force(const char *url)
  84{
  85        if (url) {
  86                const char *colon = strchr(url, ':');
  87                if (colon && colon[1] == ':')
  88                        return colon + 2;
  89        }
  90        return url;
  91}
  92
  93static void do_take_over(struct transport *transport)
  94{
  95        struct helper_data *data;
  96        data = (struct helper_data *)transport->data;
  97        transport_take_over(transport, data->helper);
  98        fclose(data->out);
  99        free(data);
 100}
 101
 102static void standard_options(struct transport *t);
 103
 104static struct child_process *get_helper(struct transport *transport)
 105{
 106        struct helper_data *data = transport->data;
 107        struct strbuf buf = STRBUF_INIT;
 108        struct child_process *helper;
 109        int duped;
 110        int code;
 111
 112        if (data->helper)
 113                return data->helper;
 114
 115        helper = xmalloc(sizeof(*helper));
 116        child_process_init(helper);
 117        helper->in = -1;
 118        helper->out = -1;
 119        helper->err = 0;
 120        argv_array_pushf(&helper->args, "git-remote-%s", data->name);
 121        argv_array_push(&helper->args, transport->remote->name);
 122        argv_array_push(&helper->args, remove_ext_force(transport->url));
 123        helper->git_cmd = 0;
 124        helper->silent_exec_failure = 1;
 125
 126        if (have_git_dir())
 127                argv_array_pushf(&helper->env_array, "%s=%s",
 128                                 GIT_DIR_ENVIRONMENT, get_git_dir());
 129
 130        helper->trace2_child_class = helper->args.argv[0]; /* "remote-<name>" */
 131
 132        code = start_command(helper);
 133        if (code < 0 && errno == ENOENT)
 134                die(_("unable to find remote helper for '%s'"), data->name);
 135        else if (code != 0)
 136                exit(code);
 137
 138        data->helper = helper;
 139        data->no_disconnect_req = 0;
 140        refspec_init(&data->rs, REFSPEC_FETCH);
 141
 142        /*
 143         * Open the output as FILE* so strbuf_getline_*() family of
 144         * functions can be used.
 145         * Do this with duped fd because fclose() will close the fd,
 146         * and stuff like taking over will require the fd to remain.
 147         */
 148        duped = dup(helper->out);
 149        if (duped < 0)
 150                die_errno(_("can't dup helper output fd"));
 151        data->out = xfdopen(duped, "r");
 152
 153        write_constant(helper->in, "capabilities\n");
 154
 155        while (1) {
 156                const char *capname, *arg;
 157                int mandatory = 0;
 158                if (recvline(data, &buf))
 159                        exit(128);
 160
 161                if (!*buf.buf)
 162                        break;
 163
 164                if (*buf.buf == '*') {
 165                        capname = buf.buf + 1;
 166                        mandatory = 1;
 167                } else
 168                        capname = buf.buf;
 169
 170                if (debug)
 171                        fprintf(stderr, "Debug: Got cap %s\n", capname);
 172                if (!strcmp(capname, "fetch"))
 173                        data->fetch = 1;
 174                else if (!strcmp(capname, "option"))
 175                        data->option = 1;
 176                else if (!strcmp(capname, "push"))
 177                        data->push = 1;
 178                else if (!strcmp(capname, "import"))
 179                        data->import = 1;
 180                else if (!strcmp(capname, "bidi-import"))
 181                        data->bidi_import = 1;
 182                else if (!strcmp(capname, "export"))
 183                        data->export = 1;
 184                else if (!strcmp(capname, "check-connectivity"))
 185                        data->check_connectivity = 1;
 186                else if (skip_prefix(capname, "refspec ", &arg)) {
 187                        refspec_append(&data->rs, arg);
 188                } else if (!strcmp(capname, "connect")) {
 189                        data->connect = 1;
 190                } else if (!strcmp(capname, "stateless-connect")) {
 191                        data->stateless_connect = 1;
 192                } else if (!strcmp(capname, "signed-tags")) {
 193                        data->signed_tags = 1;
 194                } else if (skip_prefix(capname, "export-marks ", &arg)) {
 195                        data->export_marks = xstrdup(arg);
 196                } else if (skip_prefix(capname, "import-marks ", &arg)) {
 197                        data->import_marks = xstrdup(arg);
 198                } else if (starts_with(capname, "no-private-update")) {
 199                        data->no_private_update = 1;
 200                } else if (mandatory) {
 201                        die(_("unknown mandatory capability %s; this remote "
 202                              "helper probably needs newer version of Git"),
 203                            capname);
 204                }
 205        }
 206        if (!data->rs.nr && (data->import || data->bidi_import || data->export)) {
 207                warning(_("this remote helper should implement refspec capability"));
 208        }
 209        strbuf_release(&buf);
 210        if (debug)
 211                fprintf(stderr, "Debug: Capabilities complete.\n");
 212        standard_options(transport);
 213        return data->helper;
 214}
 215
 216static int disconnect_helper(struct transport *transport)
 217{
 218        struct helper_data *data = transport->data;
 219        int res = 0;
 220
 221        if (data->helper) {
 222                if (debug)
 223                        fprintf(stderr, "Debug: Disconnecting.\n");
 224                if (!data->no_disconnect_req) {
 225                        /*
 226                         * Ignore write errors; there's nothing we can do,
 227                         * since we're about to close the pipe anyway. And the
 228                         * most likely error is EPIPE due to the helper dying
 229                         * to report an error itself.
 230                         */
 231                        sigchain_push(SIGPIPE, SIG_IGN);
 232                        xwrite(data->helper->in, "\n", 1);
 233                        sigchain_pop(SIGPIPE);
 234                }
 235                close(data->helper->in);
 236                close(data->helper->out);
 237                fclose(data->out);
 238                res = finish_command(data->helper);
 239                FREE_AND_NULL(data->helper);
 240        }
 241        return res;
 242}
 243
 244static const char *unsupported_options[] = {
 245        TRANS_OPT_UPLOADPACK,
 246        TRANS_OPT_RECEIVEPACK,
 247        TRANS_OPT_THIN,
 248        TRANS_OPT_KEEP
 249        };
 250
 251static const char *boolean_options[] = {
 252        TRANS_OPT_THIN,
 253        TRANS_OPT_KEEP,
 254        TRANS_OPT_FOLLOWTAGS,
 255        TRANS_OPT_DEEPEN_RELATIVE
 256        };
 257
 258static int strbuf_set_helper_option(struct helper_data *data,
 259                                    struct strbuf *buf)
 260{
 261        int ret;
 262
 263        sendline(data, buf);
 264        if (recvline(data, buf))
 265                exit(128);
 266
 267        if (!strcmp(buf->buf, "ok"))
 268                ret = 0;
 269        else if (starts_with(buf->buf, "error"))
 270                ret = -1;
 271        else if (!strcmp(buf->buf, "unsupported"))
 272                ret = 1;
 273        else {
 274                warning(_("%s unexpectedly said: '%s'"), data->name, buf->buf);
 275                ret = 1;
 276        }
 277        return ret;
 278}
 279
 280static int string_list_set_helper_option(struct helper_data *data,
 281                                         const char *name,
 282                                         struct string_list *list)
 283{
 284        struct strbuf buf = STRBUF_INIT;
 285        int i, ret = 0;
 286
 287        for (i = 0; i < list->nr; i++) {
 288                strbuf_addf(&buf, "option %s ", name);
 289                quote_c_style(list->items[i].string, &buf, NULL, 0);
 290                strbuf_addch(&buf, '\n');
 291
 292                if ((ret = strbuf_set_helper_option(data, &buf)))
 293                        break;
 294                strbuf_reset(&buf);
 295        }
 296        strbuf_release(&buf);
 297        return ret;
 298}
 299
 300static int set_helper_option(struct transport *transport,
 301                          const char *name, const char *value)
 302{
 303        struct helper_data *data = transport->data;
 304        struct strbuf buf = STRBUF_INIT;
 305        int i, ret, is_bool = 0;
 306
 307        get_helper(transport);
 308
 309        if (!data->option)
 310                return 1;
 311
 312        if (!strcmp(name, "deepen-not"))
 313                return string_list_set_helper_option(data, name,
 314                                                     (struct string_list *)value);
 315
 316        for (i = 0; i < ARRAY_SIZE(unsupported_options); i++) {
 317                if (!strcmp(name, unsupported_options[i]))
 318                        return 1;
 319        }
 320
 321        for (i = 0; i < ARRAY_SIZE(boolean_options); i++) {
 322                if (!strcmp(name, boolean_options[i])) {
 323                        is_bool = 1;
 324                        break;
 325                }
 326        }
 327
 328        strbuf_addf(&buf, "option %s ", name);
 329        if (is_bool)
 330                strbuf_addstr(&buf, value ? "true" : "false");
 331        else
 332                quote_c_style(value, &buf, NULL, 0);
 333        strbuf_addch(&buf, '\n');
 334
 335        ret = strbuf_set_helper_option(data, &buf);
 336        strbuf_release(&buf);
 337        return ret;
 338}
 339
 340static void standard_options(struct transport *t)
 341{
 342        char buf[16];
 343        int v = t->verbose;
 344
 345        set_helper_option(t, "progress", t->progress ? "true" : "false");
 346
 347        xsnprintf(buf, sizeof(buf), "%d", v + 1);
 348        set_helper_option(t, "verbosity", buf);
 349
 350        switch (t->family) {
 351        case TRANSPORT_FAMILY_ALL:
 352                /*
 353                 * this is already the default,
 354                 * do not break old remote helpers by setting "all" here
 355                 */
 356                break;
 357        case TRANSPORT_FAMILY_IPV4:
 358                set_helper_option(t, "family", "ipv4");
 359                break;
 360        case TRANSPORT_FAMILY_IPV6:
 361                set_helper_option(t, "family", "ipv6");
 362                break;
 363        }
 364}
 365
 366static int release_helper(struct transport *transport)
 367{
 368        int res = 0;
 369        struct helper_data *data = transport->data;
 370        refspec_clear(&data->rs);
 371        res = disconnect_helper(transport);
 372        free(transport->data);
 373        return res;
 374}
 375
 376static int fetch_with_fetch(struct transport *transport,
 377                            int nr_heads, struct ref **to_fetch)
 378{
 379        struct helper_data *data = transport->data;
 380        int i;
 381        struct strbuf buf = STRBUF_INIT;
 382
 383        for (i = 0; i < nr_heads; i++) {
 384                const struct ref *posn = to_fetch[i];
 385                if (posn->status & REF_STATUS_UPTODATE)
 386                        continue;
 387
 388                strbuf_addf(&buf, "fetch %s %s\n",
 389                            oid_to_hex(&posn->old_oid),
 390                            posn->symref ? posn->symref : posn->name);
 391        }
 392
 393        strbuf_addch(&buf, '\n');
 394        sendline(data, &buf);
 395
 396        while (1) {
 397                if (recvline(data, &buf))
 398                        exit(128);
 399
 400                if (starts_with(buf.buf, "lock ")) {
 401                        const char *name = buf.buf + 5;
 402                        if (transport->pack_lockfile)
 403                                warning(_("%s also locked %s"), data->name, name);
 404                        else
 405                                transport->pack_lockfile = xstrdup(name);
 406                }
 407                else if (data->check_connectivity &&
 408                         data->transport_options.check_self_contained_and_connected &&
 409                         !strcmp(buf.buf, "connectivity-ok"))
 410                        data->transport_options.self_contained_and_connected = 1;
 411                else if (!buf.len)
 412                        break;
 413                else
 414                        warning(_("%s unexpectedly said: '%s'"), data->name, buf.buf);
 415        }
 416        strbuf_release(&buf);
 417        return 0;
 418}
 419
 420static int get_importer(struct transport *transport, struct child_process *fastimport)
 421{
 422        struct child_process *helper = get_helper(transport);
 423        struct helper_data *data = transport->data;
 424        int cat_blob_fd, code;
 425        child_process_init(fastimport);
 426        fastimport->in = helper->out;
 427        argv_array_push(&fastimport->args, "fast-import");
 428        argv_array_push(&fastimport->args, debug ? "--stats" : "--quiet");
 429
 430        if (data->bidi_import) {
 431                cat_blob_fd = xdup(helper->in);
 432                argv_array_pushf(&fastimport->args, "--cat-blob-fd=%d", cat_blob_fd);
 433        }
 434        fastimport->git_cmd = 1;
 435
 436        code = start_command(fastimport);
 437        return code;
 438}
 439
 440static int get_exporter(struct transport *transport,
 441                        struct child_process *fastexport,
 442                        struct string_list *revlist_args)
 443{
 444        struct helper_data *data = transport->data;
 445        struct child_process *helper = get_helper(transport);
 446        int i;
 447
 448        child_process_init(fastexport);
 449
 450        /* we need to duplicate helper->in because we want to use it after
 451         * fastexport is done with it. */
 452        fastexport->out = dup(helper->in);
 453        argv_array_push(&fastexport->args, "fast-export");
 454        argv_array_push(&fastexport->args, "--use-done-feature");
 455        argv_array_push(&fastexport->args, data->signed_tags ?
 456                "--signed-tags=verbatim" : "--signed-tags=warn-strip");
 457        if (data->export_marks)
 458                argv_array_pushf(&fastexport->args, "--export-marks=%s.tmp", data->export_marks);
 459        if (data->import_marks)
 460                argv_array_pushf(&fastexport->args, "--import-marks=%s", data->import_marks);
 461
 462        for (i = 0; i < revlist_args->nr; i++)
 463                argv_array_push(&fastexport->args, revlist_args->items[i].string);
 464
 465        fastexport->git_cmd = 1;
 466        return start_command(fastexport);
 467}
 468
 469static int fetch_with_import(struct transport *transport,
 470                             int nr_heads, struct ref **to_fetch)
 471{
 472        struct child_process fastimport;
 473        struct helper_data *data = transport->data;
 474        int i;
 475        struct ref *posn;
 476        struct strbuf buf = STRBUF_INIT;
 477
 478        get_helper(transport);
 479
 480        if (get_importer(transport, &fastimport))
 481                die(_("couldn't run fast-import"));
 482
 483        for (i = 0; i < nr_heads; i++) {
 484                posn = to_fetch[i];
 485                if (posn->status & REF_STATUS_UPTODATE)
 486                        continue;
 487
 488                strbuf_addf(&buf, "import %s\n",
 489                            posn->symref ? posn->symref : posn->name);
 490                sendline(data, &buf);
 491                strbuf_reset(&buf);
 492        }
 493
 494        write_constant(data->helper->in, "\n");
 495        /*
 496         * remote-helpers that advertise the bidi-import capability are required to
 497         * buffer the complete batch of import commands until this newline before
 498         * sending data to fast-import.
 499         * These helpers read back data from fast-import on their stdin, which could
 500         * be mixed with import commands, otherwise.
 501         */
 502
 503        if (finish_command(&fastimport))
 504                die(_("error while running fast-import"));
 505
 506        /*
 507         * The fast-import stream of a remote helper that advertises
 508         * the "refspec" capability writes to the refs named after the
 509         * right hand side of the first refspec matching each ref we
 510         * were fetching.
 511         *
 512         * (If no "refspec" capability was specified, for historical
 513         * reasons we default to the equivalent of *:*.)
 514         *
 515         * Store the result in to_fetch[i].old_sha1.  Callers such
 516         * as "git fetch" can use the value to write feedback to the
 517         * terminal, populate FETCH_HEAD, and determine what new value
 518         * should be written to peer_ref if the update is a
 519         * fast-forward or this is a forced update.
 520         */
 521        for (i = 0; i < nr_heads; i++) {
 522                char *private, *name;
 523                posn = to_fetch[i];
 524                if (posn->status & REF_STATUS_UPTODATE)
 525                        continue;
 526                name = posn->symref ? posn->symref : posn->name;
 527                if (data->rs.nr)
 528                        private = apply_refspecs(&data->rs, name);
 529                else
 530                        private = xstrdup(name);
 531                if (private) {
 532                        if (read_ref(private, &posn->old_oid) < 0)
 533                                die(_("could not read ref %s"), private);
 534                        free(private);
 535                }
 536        }
 537        strbuf_release(&buf);
 538        return 0;
 539}
 540
 541static int run_connect(struct transport *transport, struct strbuf *cmdbuf)
 542{
 543        struct helper_data *data = transport->data;
 544        int ret = 0;
 545        int duped;
 546        FILE *input;
 547        struct child_process *helper;
 548
 549        helper = get_helper(transport);
 550
 551        /*
 552         * Yes, dup the pipe another time, as we need unbuffered version
 553         * of input pipe as FILE*. fclose() closes the underlying fd and
 554         * stream buffering only can be changed before first I/O operation
 555         * on it.
 556         */
 557        duped = dup(helper->out);
 558        if (duped < 0)
 559                die_errno(_("can't dup helper output fd"));
 560        input = xfdopen(duped, "r");
 561        setvbuf(input, NULL, _IONBF, 0);
 562
 563        sendline(data, cmdbuf);
 564        if (recvline_fh(input, cmdbuf))
 565                exit(128);
 566
 567        if (!strcmp(cmdbuf->buf, "")) {
 568                data->no_disconnect_req = 1;
 569                if (debug)
 570                        fprintf(stderr, "Debug: Smart transport connection "
 571                                "ready.\n");
 572                ret = 1;
 573        } else if (!strcmp(cmdbuf->buf, "fallback")) {
 574                if (debug)
 575                        fprintf(stderr, "Debug: Falling back to dumb "
 576                                "transport.\n");
 577        } else {
 578                die(_("unknown response to connect: %s"),
 579                    cmdbuf->buf);
 580        }
 581
 582        fclose(input);
 583        return ret;
 584}
 585
 586static int process_connect_service(struct transport *transport,
 587                                   const char *name, const char *exec)
 588{
 589        struct helper_data *data = transport->data;
 590        struct strbuf cmdbuf = STRBUF_INIT;
 591        int ret = 0;
 592
 593        /*
 594         * Handle --upload-pack and friends. This is fire and forget...
 595         * just warn if it fails.
 596         */
 597        if (strcmp(name, exec)) {
 598                int r = set_helper_option(transport, "servpath", exec);
 599                if (r > 0)
 600                        warning(_("setting remote service path not supported by protocol"));
 601                else if (r < 0)
 602                        warning(_("invalid remote service path"));
 603        }
 604
 605        if (data->connect) {
 606                strbuf_addf(&cmdbuf, "connect %s\n", name);
 607                ret = run_connect(transport, &cmdbuf);
 608        } else if (data->stateless_connect &&
 609                   (get_protocol_version_config() == protocol_v2) &&
 610                   !strcmp("git-upload-pack", name)) {
 611                strbuf_addf(&cmdbuf, "stateless-connect %s\n", name);
 612                ret = run_connect(transport, &cmdbuf);
 613                if (ret)
 614                        transport->stateless_rpc = 1;
 615        }
 616
 617        strbuf_release(&cmdbuf);
 618        return ret;
 619}
 620
 621static int process_connect(struct transport *transport,
 622                                     int for_push)
 623{
 624        struct helper_data *data = transport->data;
 625        const char *name;
 626        const char *exec;
 627
 628        name = for_push ? "git-receive-pack" : "git-upload-pack";
 629        if (for_push)
 630                exec = data->transport_options.receivepack;
 631        else
 632                exec = data->transport_options.uploadpack;
 633
 634        return process_connect_service(transport, name, exec);
 635}
 636
 637static int connect_helper(struct transport *transport, const char *name,
 638                   const char *exec, int fd[2])
 639{
 640        struct helper_data *data = transport->data;
 641
 642        /* Get_helper so connect is inited. */
 643        get_helper(transport);
 644        if (!data->connect)
 645                die(_("operation not supported by protocol"));
 646
 647        if (!process_connect_service(transport, name, exec))
 648                die(_("can't connect to subservice %s"), name);
 649
 650        fd[0] = data->helper->out;
 651        fd[1] = data->helper->in;
 652        return 0;
 653}
 654
 655static int fetch(struct transport *transport,
 656                 int nr_heads, struct ref **to_fetch)
 657{
 658        struct helper_data *data = transport->data;
 659        int i, count;
 660
 661        if (process_connect(transport, 0)) {
 662                do_take_over(transport);
 663                return transport->vtable->fetch(transport, nr_heads, to_fetch);
 664        }
 665
 666        count = 0;
 667        for (i = 0; i < nr_heads; i++)
 668                if (!(to_fetch[i]->status & REF_STATUS_UPTODATE))
 669                        count++;
 670
 671        if (!count)
 672                return 0;
 673
 674        if (data->check_connectivity &&
 675            data->transport_options.check_self_contained_and_connected)
 676                set_helper_option(transport, "check-connectivity", "true");
 677
 678        if (transport->cloning)
 679                set_helper_option(transport, "cloning", "true");
 680
 681        if (data->transport_options.update_shallow)
 682                set_helper_option(transport, "update-shallow", "true");
 683
 684        if (data->transport_options.filter_options.choice) {
 685                struct strbuf expanded_filter_spec = STRBUF_INIT;
 686                expand_list_objects_filter_spec(
 687                        &data->transport_options.filter_options,
 688                        &expanded_filter_spec);
 689                set_helper_option(transport, "filter",
 690                                  expanded_filter_spec.buf);
 691                strbuf_release(&expanded_filter_spec);
 692        }
 693
 694        if (data->transport_options.negotiation_tips)
 695                warning("Ignoring --negotiation-tip because the protocol does not support it.");
 696
 697        if (data->fetch)
 698                return fetch_with_fetch(transport, nr_heads, to_fetch);
 699
 700        if (data->import)
 701                return fetch_with_import(transport, nr_heads, to_fetch);
 702
 703        return -1;
 704}
 705
 706static int push_update_ref_status(struct strbuf *buf,
 707                                   struct ref **ref,
 708                                   struct ref *remote_refs)
 709{
 710        char *refname, *msg;
 711        int status, forced = 0;
 712
 713        if (starts_with(buf->buf, "ok ")) {
 714                status = REF_STATUS_OK;
 715                refname = buf->buf + 3;
 716        } else if (starts_with(buf->buf, "error ")) {
 717                status = REF_STATUS_REMOTE_REJECT;
 718                refname = buf->buf + 6;
 719        } else
 720                die(_("expected ok/error, helper said '%s'"), buf->buf);
 721
 722        msg = strchr(refname, ' ');
 723        if (msg) {
 724                struct strbuf msg_buf = STRBUF_INIT;
 725                const char *end;
 726
 727                *msg++ = '\0';
 728                if (!unquote_c_style(&msg_buf, msg, &end))
 729                        msg = strbuf_detach(&msg_buf, NULL);
 730                else
 731                        msg = xstrdup(msg);
 732                strbuf_release(&msg_buf);
 733
 734                if (!strcmp(msg, "no match")) {
 735                        status = REF_STATUS_NONE;
 736                        FREE_AND_NULL(msg);
 737                }
 738                else if (!strcmp(msg, "up to date")) {
 739                        status = REF_STATUS_UPTODATE;
 740                        FREE_AND_NULL(msg);
 741                }
 742                else if (!strcmp(msg, "non-fast forward")) {
 743                        status = REF_STATUS_REJECT_NONFASTFORWARD;
 744                        FREE_AND_NULL(msg);
 745                }
 746                else if (!strcmp(msg, "already exists")) {
 747                        status = REF_STATUS_REJECT_ALREADY_EXISTS;
 748                        FREE_AND_NULL(msg);
 749                }
 750                else if (!strcmp(msg, "fetch first")) {
 751                        status = REF_STATUS_REJECT_FETCH_FIRST;
 752                        FREE_AND_NULL(msg);
 753                }
 754                else if (!strcmp(msg, "needs force")) {
 755                        status = REF_STATUS_REJECT_NEEDS_FORCE;
 756                        FREE_AND_NULL(msg);
 757                }
 758                else if (!strcmp(msg, "stale info")) {
 759                        status = REF_STATUS_REJECT_STALE;
 760                        FREE_AND_NULL(msg);
 761                }
 762                else if (!strcmp(msg, "forced update")) {
 763                        forced = 1;
 764                        FREE_AND_NULL(msg);
 765                }
 766        }
 767
 768        if (*ref)
 769                *ref = find_ref_by_name(*ref, refname);
 770        if (!*ref)
 771                *ref = find_ref_by_name(remote_refs, refname);
 772        if (!*ref) {
 773                warning(_("helper reported unexpected status of %s"), refname);
 774                return 1;
 775        }
 776
 777        if ((*ref)->status != REF_STATUS_NONE) {
 778                /*
 779                 * Earlier, the ref was marked not to be pushed, so ignore the ref
 780                 * status reported by the remote helper if the latter is 'no match'.
 781                 */
 782                if (status == REF_STATUS_NONE)
 783                        return 1;
 784        }
 785
 786        (*ref)->status = status;
 787        (*ref)->forced_update |= forced;
 788        (*ref)->remote_status = msg;
 789        return !(status == REF_STATUS_OK);
 790}
 791
 792static int push_update_refs_status(struct helper_data *data,
 793                                    struct ref *remote_refs,
 794                                    int flags)
 795{
 796        struct strbuf buf = STRBUF_INIT;
 797        struct ref *ref = remote_refs;
 798        int ret = 0;
 799
 800        for (;;) {
 801                char *private;
 802
 803                if (recvline(data, &buf)) {
 804                        ret = 1;
 805                        break;
 806                }
 807
 808                if (!buf.len)
 809                        break;
 810
 811                if (push_update_ref_status(&buf, &ref, remote_refs))
 812                        continue;
 813
 814                if (flags & TRANSPORT_PUSH_DRY_RUN || !data->rs.nr || data->no_private_update)
 815                        continue;
 816
 817                /* propagate back the update to the remote namespace */
 818                private = apply_refspecs(&data->rs, ref->name);
 819                if (!private)
 820                        continue;
 821                update_ref("update by helper", private, &ref->new_oid, NULL,
 822                           0, 0);
 823                free(private);
 824        }
 825        strbuf_release(&buf);
 826        return ret;
 827}
 828
 829static void set_common_push_options(struct transport *transport,
 830                                   const char *name, int flags)
 831{
 832        if (flags & TRANSPORT_PUSH_DRY_RUN) {
 833                if (set_helper_option(transport, "dry-run", "true") != 0)
 834                        die(_("helper %s does not support dry-run"), name);
 835        } else if (flags & TRANSPORT_PUSH_CERT_ALWAYS) {
 836                if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "true") != 0)
 837                        die(_("helper %s does not support --signed"), name);
 838        } else if (flags & TRANSPORT_PUSH_CERT_IF_ASKED) {
 839                if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "if-asked") != 0)
 840                        die(_("helper %s does not support --signed=if-asked"), name);
 841        }
 842
 843        if (flags & TRANSPORT_PUSH_OPTIONS) {
 844                struct string_list_item *item;
 845                for_each_string_list_item(item, transport->push_options)
 846                        if (set_helper_option(transport, "push-option", item->string) != 0)
 847                                die(_("helper %s does not support 'push-option'"), name);
 848        }
 849}
 850
 851static int push_refs_with_push(struct transport *transport,
 852                               struct ref *remote_refs, int flags)
 853{
 854        int force_all = flags & TRANSPORT_PUSH_FORCE;
 855        int mirror = flags & TRANSPORT_PUSH_MIRROR;
 856        struct helper_data *data = transport->data;
 857        struct strbuf buf = STRBUF_INIT;
 858        struct ref *ref;
 859        struct string_list cas_options = STRING_LIST_INIT_DUP;
 860        struct string_list_item *cas_option;
 861
 862        get_helper(transport);
 863        if (!data->push)
 864                return 1;
 865
 866        for (ref = remote_refs; ref; ref = ref->next) {
 867                if (!ref->peer_ref && !mirror)
 868                        continue;
 869
 870                /* Check for statuses set by set_ref_status_for_push() */
 871                switch (ref->status) {
 872                case REF_STATUS_REJECT_NONFASTFORWARD:
 873                case REF_STATUS_REJECT_STALE:
 874                case REF_STATUS_REJECT_ALREADY_EXISTS:
 875                case REF_STATUS_UPTODATE:
 876                        continue;
 877                default:
 878                        ; /* do nothing */
 879                }
 880
 881                if (force_all)
 882                        ref->force = 1;
 883
 884                strbuf_addstr(&buf, "push ");
 885                if (!ref->deletion) {
 886                        if (ref->force)
 887                                strbuf_addch(&buf, '+');
 888                        if (ref->peer_ref)
 889                                strbuf_addstr(&buf, ref->peer_ref->name);
 890                        else
 891                                strbuf_addstr(&buf, oid_to_hex(&ref->new_oid));
 892                }
 893                strbuf_addch(&buf, ':');
 894                strbuf_addstr(&buf, ref->name);
 895                strbuf_addch(&buf, '\n');
 896
 897                /*
 898                 * The "--force-with-lease" options without explicit
 899                 * values to expect have already been expanded into
 900                 * the ref->old_oid_expect[] field; we can ignore
 901                 * transport->smart_options->cas altogether and instead
 902                 * can enumerate them from the refs.
 903                 */
 904                if (ref->expect_old_sha1) {
 905                        struct strbuf cas = STRBUF_INIT;
 906                        strbuf_addf(&cas, "%s:%s",
 907                                    ref->name, oid_to_hex(&ref->old_oid_expect));
 908                        string_list_append_nodup(&cas_options,
 909                                                 strbuf_detach(&cas, NULL));
 910                }
 911        }
 912        if (buf.len == 0) {
 913                string_list_clear(&cas_options, 0);
 914                return 0;
 915        }
 916
 917        for_each_string_list_item(cas_option, &cas_options)
 918                set_helper_option(transport, "cas", cas_option->string);
 919        set_common_push_options(transport, data->name, flags);
 920
 921        strbuf_addch(&buf, '\n');
 922        sendline(data, &buf);
 923        strbuf_release(&buf);
 924        string_list_clear(&cas_options, 0);
 925
 926        return push_update_refs_status(data, remote_refs, flags);
 927}
 928
 929static int push_refs_with_export(struct transport *transport,
 930                struct ref *remote_refs, int flags)
 931{
 932        struct ref *ref;
 933        struct child_process *helper, exporter;
 934        struct helper_data *data = transport->data;
 935        struct string_list revlist_args = STRING_LIST_INIT_DUP;
 936        struct strbuf buf = STRBUF_INIT;
 937
 938        if (!data->rs.nr)
 939                die(_("remote-helper doesn't support push; refspec needed"));
 940
 941        set_common_push_options(transport, data->name, flags);
 942        if (flags & TRANSPORT_PUSH_FORCE) {
 943                if (set_helper_option(transport, "force", "true") != 0)
 944                        warning(_("helper %s does not support 'force'"), data->name);
 945        }
 946
 947        helper = get_helper(transport);
 948
 949        write_constant(helper->in, "export\n");
 950
 951        for (ref = remote_refs; ref; ref = ref->next) {
 952                char *private;
 953                struct object_id oid;
 954
 955                private = apply_refspecs(&data->rs, ref->name);
 956                if (private && !get_oid(private, &oid)) {
 957                        strbuf_addf(&buf, "^%s", private);
 958                        string_list_append_nodup(&revlist_args,
 959                                                 strbuf_detach(&buf, NULL));
 960                        oidcpy(&ref->old_oid, &oid);
 961                }
 962                free(private);
 963
 964                if (ref->peer_ref) {
 965                        if (strcmp(ref->name, ref->peer_ref->name)) {
 966                                if (!ref->deletion) {
 967                                        const char *name;
 968                                        int flag;
 969
 970                                        /* Follow symbolic refs (mainly for HEAD). */
 971                                        name = resolve_ref_unsafe(ref->peer_ref->name,
 972                                                                  RESOLVE_REF_READING,
 973                                                                  &oid, &flag);
 974                                        if (!name || !(flag & REF_ISSYMREF))
 975                                                name = ref->peer_ref->name;
 976
 977                                        strbuf_addf(&buf, "%s:%s", name, ref->name);
 978                                } else
 979                                        strbuf_addf(&buf, ":%s", ref->name);
 980
 981                                string_list_append(&revlist_args, "--refspec");
 982                                string_list_append(&revlist_args, buf.buf);
 983                                strbuf_release(&buf);
 984                        }
 985                        if (!ref->deletion)
 986                                string_list_append(&revlist_args, ref->peer_ref->name);
 987                }
 988        }
 989
 990        if (get_exporter(transport, &exporter, &revlist_args))
 991                die(_("couldn't run fast-export"));
 992
 993        string_list_clear(&revlist_args, 1);
 994
 995        if (finish_command(&exporter))
 996                die(_("error while running fast-export"));
 997        if (push_update_refs_status(data, remote_refs, flags))
 998                return 1;
 999
1000        if (data->export_marks) {
1001                strbuf_addf(&buf, "%s.tmp", data->export_marks);
1002                rename(buf.buf, data->export_marks);
1003                strbuf_release(&buf);
1004        }
1005
1006        return 0;
1007}
1008
1009static int push_refs(struct transport *transport,
1010                struct ref *remote_refs, int flags)
1011{
1012        struct helper_data *data = transport->data;
1013
1014        if (process_connect(transport, 1)) {
1015                do_take_over(transport);
1016                return transport->vtable->push_refs(transport, remote_refs, flags);
1017        }
1018
1019        if (!remote_refs) {
1020                fprintf(stderr,
1021                        _("No refs in common and none specified; doing nothing.\n"
1022                          "Perhaps you should specify a branch such as 'master'.\n"));
1023                return 0;
1024        }
1025
1026        if (data->push)
1027                return push_refs_with_push(transport, remote_refs, flags);
1028
1029        if (data->export)
1030                return push_refs_with_export(transport, remote_refs, flags);
1031
1032        return -1;
1033}
1034
1035
1036static int has_attribute(const char *attrs, const char *attr)
1037{
1038        int len;
1039        if (!attrs)
1040                return 0;
1041
1042        len = strlen(attr);
1043        for (;;) {
1044                const char *space = strchrnul(attrs, ' ');
1045                if (len == space - attrs && !strncmp(attrs, attr, len))
1046                        return 1;
1047                if (!*space)
1048                        return 0;
1049                attrs = space + 1;
1050        }
1051}
1052
1053static struct ref *get_refs_list(struct transport *transport, int for_push,
1054                                 const struct argv_array *ref_prefixes)
1055{
1056        struct helper_data *data = transport->data;
1057        struct child_process *helper;
1058        struct ref *ret = NULL;
1059        struct ref **tail = &ret;
1060        struct ref *posn;
1061        struct strbuf buf = STRBUF_INIT;
1062
1063        helper = get_helper(transport);
1064
1065        if (process_connect(transport, for_push)) {
1066                do_take_over(transport);
1067                return transport->vtable->get_refs_list(transport, for_push, ref_prefixes);
1068        }
1069
1070        if (data->push && for_push)
1071                write_str_in_full(helper->in, "list for-push\n");
1072        else
1073                write_str_in_full(helper->in, "list\n");
1074
1075        while (1) {
1076                char *eov, *eon;
1077                if (recvline(data, &buf))
1078                        exit(128);
1079
1080                if (!*buf.buf)
1081                        break;
1082
1083                eov = strchr(buf.buf, ' ');
1084                if (!eov)
1085                        die(_("malformed response in ref list: %s"), buf.buf);
1086                eon = strchr(eov + 1, ' ');
1087                *eov = '\0';
1088                if (eon)
1089                        *eon = '\0';
1090                *tail = alloc_ref(eov + 1);
1091                if (buf.buf[0] == '@')
1092                        (*tail)->symref = xstrdup(buf.buf + 1);
1093                else if (buf.buf[0] != '?')
1094                        get_oid_hex(buf.buf, &(*tail)->old_oid);
1095                if (eon) {
1096                        if (has_attribute(eon + 1, "unchanged")) {
1097                                (*tail)->status |= REF_STATUS_UPTODATE;
1098                                if (read_ref((*tail)->name, &(*tail)->old_oid) < 0)
1099                                        die(_("could not read ref %s"),
1100                                            (*tail)->name);
1101                        }
1102                }
1103                tail = &((*tail)->next);
1104        }
1105        if (debug)
1106                fprintf(stderr, "Debug: Read ref listing.\n");
1107        strbuf_release(&buf);
1108
1109        for (posn = ret; posn; posn = posn->next)
1110                resolve_remote_symref(posn, ret);
1111
1112        return ret;
1113}
1114
1115static struct transport_vtable vtable = {
1116        0,
1117        set_helper_option,
1118        get_refs_list,
1119        fetch,
1120        push_refs,
1121        connect_helper,
1122        release_helper
1123};
1124
1125int transport_helper_init(struct transport *transport, const char *name)
1126{
1127        struct helper_data *data = xcalloc(1, sizeof(*data));
1128        data->name = name;
1129
1130        transport_check_allowed(name);
1131
1132        if (getenv("GIT_TRANSPORT_HELPER_DEBUG"))
1133                debug = 1;
1134
1135        transport->data = data;
1136        transport->vtable = &vtable;
1137        transport->smart_options = &(data->transport_options);
1138        return 0;
1139}
1140
1141/*
1142 * Linux pipes can buffer 65536 bytes at once (and most platforms can
1143 * buffer less), so attempt reads and writes with up to that size.
1144 */
1145#define BUFFERSIZE 65536
1146/* This should be enough to hold debugging message. */
1147#define PBUFFERSIZE 8192
1148
1149/* Print bidirectional transfer loop debug message. */
1150__attribute__((format (printf, 1, 2)))
1151static void transfer_debug(const char *fmt, ...)
1152{
1153        /*
1154         * NEEDSWORK: This function is sometimes used from multiple threads, and
1155         * we end up using debug_enabled racily. That "should not matter" since
1156         * we always write the same value, but it's still wrong. This function
1157         * is listed in .tsan-suppressions for the time being.
1158         */
1159
1160        va_list args;
1161        char msgbuf[PBUFFERSIZE];
1162        static int debug_enabled = -1;
1163
1164        if (debug_enabled < 0)
1165                debug_enabled = getenv("GIT_TRANSLOOP_DEBUG") ? 1 : 0;
1166        if (!debug_enabled)
1167                return;
1168
1169        va_start(args, fmt);
1170        vsnprintf(msgbuf, PBUFFERSIZE, fmt, args);
1171        va_end(args);
1172        fprintf(stderr, "Transfer loop debugging: %s\n", msgbuf);
1173}
1174
1175/* Stream state: More data may be coming in this direction. */
1176#define SSTATE_TRANSFERRING 0
1177/*
1178 * Stream state: No more data coming in this direction, flushing rest of
1179 * data.
1180 */
1181#define SSTATE_FLUSHING 1
1182/* Stream state: Transfer in this direction finished. */
1183#define SSTATE_FINISHED 2
1184
1185#define STATE_NEEDS_READING(state) ((state) <= SSTATE_TRANSFERRING)
1186#define STATE_NEEDS_WRITING(state) ((state) <= SSTATE_FLUSHING)
1187#define STATE_NEEDS_CLOSING(state) ((state) == SSTATE_FLUSHING)
1188
1189/* Unidirectional transfer. */
1190struct unidirectional_transfer {
1191        /* Source */
1192        int src;
1193        /* Destination */
1194        int dest;
1195        /* Is source socket? */
1196        int src_is_sock;
1197        /* Is destination socket? */
1198        int dest_is_sock;
1199        /* Transfer state (TRANSFERRING/FLUSHING/FINISHED) */
1200        int state;
1201        /* Buffer. */
1202        char buf[BUFFERSIZE];
1203        /* Buffer used. */
1204        size_t bufuse;
1205        /* Name of source. */
1206        const char *src_name;
1207        /* Name of destination. */
1208        const char *dest_name;
1209};
1210
1211/* Closes the target (for writing) if transfer has finished. */
1212static void udt_close_if_finished(struct unidirectional_transfer *t)
1213{
1214        if (STATE_NEEDS_CLOSING(t->state) && !t->bufuse) {
1215                t->state = SSTATE_FINISHED;
1216                if (t->dest_is_sock)
1217                        shutdown(t->dest, SHUT_WR);
1218                else
1219                        close(t->dest);
1220                transfer_debug("Closed %s.", t->dest_name);
1221        }
1222}
1223
1224/*
1225 * Tries to read data from source into buffer. If buffer is full,
1226 * no data is read. Returns 0 on success, -1 on error.
1227 */
1228static int udt_do_read(struct unidirectional_transfer *t)
1229{
1230        ssize_t bytes;
1231
1232        if (t->bufuse == BUFFERSIZE)
1233                return 0;       /* No space for more. */
1234
1235        transfer_debug("%s is readable", t->src_name);
1236        bytes = xread(t->src, t->buf + t->bufuse, BUFFERSIZE - t->bufuse);
1237        if (bytes < 0) {
1238                error_errno(_("read(%s) failed"), t->src_name);
1239                return -1;
1240        } else if (bytes == 0) {
1241                transfer_debug("%s EOF (with %i bytes in buffer)",
1242                        t->src_name, (int)t->bufuse);
1243                t->state = SSTATE_FLUSHING;
1244        } else if (bytes > 0) {
1245                t->bufuse += bytes;
1246                transfer_debug("Read %i bytes from %s (buffer now at %i)",
1247                        (int)bytes, t->src_name, (int)t->bufuse);
1248        }
1249        return 0;
1250}
1251
1252/* Tries to write data from buffer into destination. If buffer is empty,
1253 * no data is written. Returns 0 on success, -1 on error.
1254 */
1255static int udt_do_write(struct unidirectional_transfer *t)
1256{
1257        ssize_t bytes;
1258
1259        if (t->bufuse == 0)
1260                return 0;       /* Nothing to write. */
1261
1262        transfer_debug("%s is writable", t->dest_name);
1263        bytes = xwrite(t->dest, t->buf, t->bufuse);
1264        if (bytes < 0) {
1265                error_errno(_("write(%s) failed"), t->dest_name);
1266                return -1;
1267        } else if (bytes > 0) {
1268                t->bufuse -= bytes;
1269                if (t->bufuse)
1270                        memmove(t->buf, t->buf + bytes, t->bufuse);
1271                transfer_debug("Wrote %i bytes to %s (buffer now at %i)",
1272                        (int)bytes, t->dest_name, (int)t->bufuse);
1273        }
1274        return 0;
1275}
1276
1277
1278/* State of bidirectional transfer loop. */
1279struct bidirectional_transfer_state {
1280        /* Direction from program to git. */
1281        struct unidirectional_transfer ptg;
1282        /* Direction from git to program. */
1283        struct unidirectional_transfer gtp;
1284};
1285
1286static void *udt_copy_task_routine(void *udt)
1287{
1288        struct unidirectional_transfer *t = (struct unidirectional_transfer *)udt;
1289        while (t->state != SSTATE_FINISHED) {
1290                if (STATE_NEEDS_READING(t->state))
1291                        if (udt_do_read(t))
1292                                return NULL;
1293                if (STATE_NEEDS_WRITING(t->state))
1294                        if (udt_do_write(t))
1295                                return NULL;
1296                if (STATE_NEEDS_CLOSING(t->state))
1297                        udt_close_if_finished(t);
1298        }
1299        return udt;     /* Just some non-NULL value. */
1300}
1301
1302#ifndef NO_PTHREADS
1303
1304/*
1305 * Join thread, with appropriate errors on failure. Name is name for the
1306 * thread (for error messages). Returns 0 on success, 1 on failure.
1307 */
1308static int tloop_join(pthread_t thread, const char *name)
1309{
1310        int err;
1311        void *tret;
1312        err = pthread_join(thread, &tret);
1313        if (!tret) {
1314                error(_("%s thread failed"), name);
1315                return 1;
1316        }
1317        if (err) {
1318                error(_("%s thread failed to join: %s"), name, strerror(err));
1319                return 1;
1320        }
1321        return 0;
1322}
1323
1324/*
1325 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1326 * -1 on failure.
1327 */
1328static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1329{
1330        pthread_t gtp_thread;
1331        pthread_t ptg_thread;
1332        int err;
1333        int ret = 0;
1334        err = pthread_create(&gtp_thread, NULL, udt_copy_task_routine,
1335                &s->gtp);
1336        if (err)
1337                die(_("can't start thread for copying data: %s"), strerror(err));
1338        err = pthread_create(&ptg_thread, NULL, udt_copy_task_routine,
1339                &s->ptg);
1340        if (err)
1341                die(_("can't start thread for copying data: %s"), strerror(err));
1342
1343        ret |= tloop_join(gtp_thread, "Git to program copy");
1344        ret |= tloop_join(ptg_thread, "Program to git copy");
1345        return ret;
1346}
1347#else
1348
1349/* Close the source and target (for writing) for transfer. */
1350static void udt_kill_transfer(struct unidirectional_transfer *t)
1351{
1352        t->state = SSTATE_FINISHED;
1353        /*
1354         * Socket read end left open isn't a disaster if nobody
1355         * attempts to read from it (mingw compat headers do not
1356         * have SHUT_RD)...
1357         *
1358         * We can't fully close the socket since otherwise gtp
1359         * task would first close the socket it sends data to
1360         * while closing the ptg file descriptors.
1361         */
1362        if (!t->src_is_sock)
1363                close(t->src);
1364        if (t->dest_is_sock)
1365                shutdown(t->dest, SHUT_WR);
1366        else
1367                close(t->dest);
1368}
1369
1370/*
1371 * Join process, with appropriate errors on failure. Name is name for the
1372 * process (for error messages). Returns 0 on success, 1 on failure.
1373 */
1374static int tloop_join(pid_t pid, const char *name)
1375{
1376        int tret;
1377        if (waitpid(pid, &tret, 0) < 0) {
1378                error_errno(_("%s process failed to wait"), name);
1379                return 1;
1380        }
1381        if (!WIFEXITED(tret) || WEXITSTATUS(tret)) {
1382                error(_("%s process failed"), name);
1383                return 1;
1384        }
1385        return 0;
1386}
1387
1388/*
1389 * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1390 * -1 on failure.
1391 */
1392static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1393{
1394        pid_t pid1, pid2;
1395        int ret = 0;
1396
1397        /* Fork thread #1: git to program. */
1398        pid1 = fork();
1399        if (pid1 < 0)
1400                die_errno(_("can't start thread for copying data"));
1401        else if (pid1 == 0) {
1402                udt_kill_transfer(&s->ptg);
1403                exit(udt_copy_task_routine(&s->gtp) ? 0 : 1);
1404        }
1405
1406        /* Fork thread #2: program to git. */
1407        pid2 = fork();
1408        if (pid2 < 0)
1409                die_errno(_("can't start thread for copying data"));
1410        else if (pid2 == 0) {
1411                udt_kill_transfer(&s->gtp);
1412                exit(udt_copy_task_routine(&s->ptg) ? 0 : 1);
1413        }
1414
1415        /*
1416         * Close both streams in parent as to not interfere with
1417         * end of file detection and wait for both tasks to finish.
1418         */
1419        udt_kill_transfer(&s->gtp);
1420        udt_kill_transfer(&s->ptg);
1421        ret |= tloop_join(pid1, "Git to program copy");
1422        ret |= tloop_join(pid2, "Program to git copy");
1423        return ret;
1424}
1425#endif
1426
1427/*
1428 * Copies data from stdin to output and from input to stdout simultaneously.
1429 * Additionally filtering through given filter. If filter is NULL, uses
1430 * identity filter.
1431 */
1432int bidirectional_transfer_loop(int input, int output)
1433{
1434        struct bidirectional_transfer_state state;
1435
1436        /* Fill the state fields. */
1437        state.ptg.src = input;
1438        state.ptg.dest = 1;
1439        state.ptg.src_is_sock = (input == output);
1440        state.ptg.dest_is_sock = 0;
1441        state.ptg.state = SSTATE_TRANSFERRING;
1442        state.ptg.bufuse = 0;
1443        state.ptg.src_name = "remote input";
1444        state.ptg.dest_name = "stdout";
1445
1446        state.gtp.src = 0;
1447        state.gtp.dest = output;
1448        state.gtp.src_is_sock = 0;
1449        state.gtp.dest_is_sock = (input == output);
1450        state.gtp.state = SSTATE_TRANSFERRING;
1451        state.gtp.bufuse = 0;
1452        state.gtp.src_name = "stdin";
1453        state.gtp.dest_name = "remote output";
1454
1455        return tloop_spawnwait_tasks(&state);
1456}