git.oblomov.eu Git - git/blob - transport-helper.c

   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
  15 static int debug;
  16
  17 struct helper_data {
  18         const char *name;
  19         struct child_process *helper;
  20         FILE *out;
  21         unsigned fetch : 1,
  22                 import : 1,
  23                 bidi_import : 1,
  24                 export : 1,
  25                 option : 1,
  26                 push : 1,
  27                 connect : 1,
  28                 signed_tags : 1,
  29                 check_connectivity : 1,
  30                 no_disconnect_req : 1,
  31                 no_private_update : 1;
  32         char *export_marks;
  33         char *import_marks;
  34         /* These go from remote name (as in "list") to private name */
  35         struct refspec *refspecs;
  36         int refspec_nr;
  37         /* Transport options for fetch-pack/send-pack (should one of
  38          * those be invoked).
  39          */
  40         struct git_transport_options transport_options;
  41 };
  42
  43 static void sendline(struct helper_data *helper, struct strbuf *buffer)
  44 {
  45         if (debug)
  46                 fprintf(stderr, "Debug: Remote helper: -> %s", buffer->buf);
  47         if (write_in_full(helper->helper->in, buffer->buf, buffer->len)
  48                 != buffer->len)
  49                 die_errno("Full write to remote helper failed");
  50 }
  51
  52 static int recvline_fh(FILE *helper, struct strbuf *buffer, const char *name)
  53 {
  54         strbuf_reset(buffer);
  55         if (debug)
  56                 fprintf(stderr, "Debug: Remote helper: Waiting...\n");
  57         if (strbuf_getline(buffer, helper) == EOF) {
  58                 if (debug)
  59                         fprintf(stderr, "Debug: Remote helper quit.\n");
  60                 return 1;
  61         }
  62
  63         if (debug)
  64                 fprintf(stderr, "Debug: Remote helper: <- %s\n", buffer->buf);
  65         return 0;
  66 }
  67
  68 static int recvline(struct helper_data *helper, struct strbuf *buffer)
  69 {
  70         return recvline_fh(helper->out, buffer, helper->name);
  71 }
  72
  73 static void write_constant(int fd, const char *str)
  74 {
  75         if (debug)
  76                 fprintf(stderr, "Debug: Remote helper: -> %s", str);
  77         if (write_in_full(fd, str, strlen(str)) != strlen(str))
  78                 die_errno("Full write to remote helper failed");
  79 }
  80
  81 static const char *remove_ext_force(const char *url)
  82 {
  83         if (url) {
  84                 const char *colon = strchr(url, ':');
  85                 if (colon && colon[1] == ':')
  86                         return colon + 2;
  87         }
  88         return url;
  89 }
  90
  91 static void do_take_over(struct transport *transport)
  92 {
  93         struct helper_data *data;
  94         data = (struct helper_data *)transport->data;
  95         transport_take_over(transport, data->helper);
  96         fclose(data->out);
  97         free(data);
  98 }
  99
 100 static void standard_options(struct transport *t);
 101
 102 static struct child_process *get_helper(struct transport *transport)
 103 {
 104         struct helper_data *data = transport->data;
 105         struct strbuf buf = STRBUF_INIT;
 106         struct child_process *helper;
 107         const char **refspecs = NULL;
 108         int refspec_nr = 0;
 109         int refspec_alloc = 0;
 110         int duped;
 111         int code;
 112
 113         if (data->helper)
 114                 return data->helper;
 115
 116         helper = xmalloc(sizeof(*helper));
 117         child_process_init(helper);
 118         helper->in = -1;
 119         helper->out = -1;
 120         helper->err = 0;
 121         argv_array_pushf(&helper->args, "git-remote-%s", data->name);
 122         argv_array_push(&helper->args, transport->remote->name);
 123         argv_array_push(&helper->args, remove_ext_force(transport->url));
 124         helper->git_cmd = 0;
 125         helper->silent_exec_failure = 1;
 126
 127         argv_array_pushf(&helper->env_array, "%s=%s", GIT_DIR_ENVIRONMENT,
 128                          get_git_dir());
 129
 130         code = start_command(helper);
 131         if (code < 0 && errno == ENOENT)
 132                 die("Unable to find remote helper for '%s'", data->name);
 133         else if (code != 0)
 134                 exit(code);
 135
 136         data->helper = helper;
 137         data->no_disconnect_req = 0;
 138
 139         /*
 140          * Open the output as FILE* so strbuf_getline_*() family of
 141          * functions can be used.
 142          * Do this with duped fd because fclose() will close the fd,
 143          * and stuff like taking over will require the fd to remain.
 144          */
 145         duped = dup(helper->out);
 146         if (duped < 0)
 147                 die_errno("Can't dup helper output fd");
 148         data->out = xfdopen(duped, "r");
 149
 150         write_constant(helper->in, "capabilities\n");
 151
 152         while (1) {
 153                 const char *capname, *arg;
 154                 int mandatory = 0;
 155                 if (recvline(data, &buf))
 156                         exit(128);
 157
 158                 if (!*buf.buf)
 159                         break;
 160
 161                 if (*buf.buf == '*') {
 162                         capname = buf.buf + 1;
 163                         mandatory = 1;
 164                 } else
 165                         capname = buf.buf;
 166
 167                 if (debug)
 168                         fprintf(stderr, "Debug: Got cap %s\n", capname);
 169                 if (!strcmp(capname, "fetch"))
 170                         data->fetch = 1;
 171                 else if (!strcmp(capname, "option"))
 172                         data->option = 1;
 173                 else if (!strcmp(capname, "push"))
 174                         data->push = 1;
 175                 else if (!strcmp(capname, "import"))
 176                         data->import = 1;
 177                 else if (!strcmp(capname, "bidi-import"))
 178                         data->bidi_import = 1;
 179                 else if (!strcmp(capname, "export"))
 180                         data->export = 1;
 181                 else if (!strcmp(capname, "check-connectivity"))
 182                         data->check_connectivity = 1;
 183                 else if (!data->refspecs && skip_prefix(capname, "refspec ", &arg)) {
 184                         ALLOC_GROW(refspecs,
 185                                    refspec_nr + 1,
 186                                    refspec_alloc);
 187                         refspecs[refspec_nr++] = xstrdup(arg);
 188                 } else if (!strcmp(capname, "connect")) {
 189                         data->connect = 1;
 190                 } else if (!strcmp(capname, "signed-tags")) {
 191                         data->signed_tags = 1;
 192                 } else if (skip_prefix(capname, "export-marks ", &arg)) {
 193                         data->export_marks = xstrdup(arg);
 194                 } else if (skip_prefix(capname, "import-marks ", &arg)) {
 195                         data->import_marks = xstrdup(arg);
 196                 } else if (starts_with(capname, "no-private-update")) {
 197                         data->no_private_update = 1;
 198                 } else if (mandatory) {
 199                         die("Unknown mandatory capability %s. This remote "
 200                             "helper probably needs newer version of Git.",
 201                             capname);
 202                 }
 203         }
 204         if (refspecs) {
 205                 int i;
 206                 data->refspec_nr = refspec_nr;
 207                 data->refspecs = parse_fetch_refspec(refspec_nr, refspecs);
 208                 for (i = 0; i < refspec_nr; i++)
 209                         free((char *)refspecs[i]);
 210                 free(refspecs);
 211         } else if (data->import || data->bidi_import || data->export) {
 212                 warning("This remote helper should implement refspec capability.");
 213         }
 214         strbuf_release(&buf);
 215         if (debug)
 216                 fprintf(stderr, "Debug: Capabilities complete.\n");
 217         standard_options(transport);
 218         return data->helper;
 219 }
 220
 221 static int disconnect_helper(struct transport *transport)
 222 {
 223         struct helper_data *data = transport->data;
 224         int res = 0;
 225
 226         if (data->helper) {
 227                 if (debug)
 228                         fprintf(stderr, "Debug: Disconnecting.\n");
 229                 if (!data->no_disconnect_req) {
 230                         /*
 231                          * Ignore write errors; there's nothing we can do,
 232                          * since we're about to close the pipe anyway. And the
 233                          * most likely error is EPIPE due to the helper dying
 234                          * to report an error itself.
 235                          */
 236                         sigchain_push(SIGPIPE, SIG_IGN);
 237                         xwrite(data->helper->in, "\n", 1);
 238                         sigchain_pop(SIGPIPE);
 239                 }
 240                 close(data->helper->in);
 241                 close(data->helper->out);
 242                 fclose(data->out);
 243                 res = finish_command(data->helper);
 244                 free(data->helper);
 245                 data->helper = NULL;
 246         }
 247         return res;
 248 }
 249
 250 static const char *unsupported_options[] = {
 251         TRANS_OPT_UPLOADPACK,
 252         TRANS_OPT_RECEIVEPACK,
 253         TRANS_OPT_THIN,
 254         TRANS_OPT_KEEP
 255         };
 256
 257 static const char *boolean_options[] = {
 258         TRANS_OPT_THIN,
 259         TRANS_OPT_KEEP,
 260         TRANS_OPT_FOLLOWTAGS,
 261         };
 262
 263 static int set_helper_option(struct transport *transport,
 264                           const char *name, const char *value)
 265 {
 266         struct helper_data *data = transport->data;
 267         struct strbuf buf = STRBUF_INIT;
 268         int i, ret, is_bool = 0;
 269
 270         get_helper(transport);
 271
 272         if (!data->option)
 273                 return 1;
 274
 275         for (i = 0; i < ARRAY_SIZE(unsupported_options); i++) {
 276                 if (!strcmp(name, unsupported_options[i]))
 277                         return 1;
 278         }
 279
 280         for (i = 0; i < ARRAY_SIZE(boolean_options); i++) {
 281                 if (!strcmp(name, boolean_options[i])) {
 282                         is_bool = 1;
 283                         break;
 284                 }
 285         }
 286
 287         strbuf_addf(&buf, "option %s ", name);
 288         if (is_bool)
 289                 strbuf_addstr(&buf, value ? "true" : "false");
 290         else
 291                 quote_c_style(value, &buf, NULL, 0);
 292         strbuf_addch(&buf, '\n');
 293
 294         sendline(data, &buf);
 295         if (recvline(data, &buf))
 296                 exit(128);
 297
 298         if (!strcmp(buf.buf, "ok"))
 299                 ret = 0;
 300         else if (starts_with(buf.buf, "error")) {
 301                 ret = -1;
 302         } else if (!strcmp(buf.buf, "unsupported"))
 303                 ret = 1;
 304         else {
 305                 warning("%s unexpectedly said: '%s'", data->name, buf.buf);
 306                 ret = 1;
 307         }
 308         strbuf_release(&buf);
 309         return ret;
 310 }
 311
 312 static void standard_options(struct transport *t)
 313 {
 314         char buf[16];
 315         int n;
 316         int v = t->verbose;
 317
 318         set_helper_option(t, "progress", t->progress ? "true" : "false");
 319
 320         n = snprintf(buf, sizeof(buf), "%d", v + 1);
 321         if (n >= sizeof(buf))
 322                 die("impossibly large verbosity value");
 323         set_helper_option(t, "verbosity", buf);
 324
 325         switch (t->family) {
 326         case TRANSPORT_FAMILY_ALL:
 327                 /*
 328                  * this is already the default,
 329                  * do not break old remote helpers by setting "all" here
 330                  */
 331                 break;
 332         case TRANSPORT_FAMILY_IPV4:
 333                 set_helper_option(t, "family", "ipv4");
 334                 break;
 335         case TRANSPORT_FAMILY_IPV6:
 336                 set_helper_option(t, "family", "ipv6");
 337                 break;
 338         }
 339 }
 340
 341 static int release_helper(struct transport *transport)
 342 {
 343         int res = 0;
 344         struct helper_data *data = transport->data;
 345         free_refspec(data->refspec_nr, data->refspecs);
 346         data->refspecs = NULL;
 347         res = disconnect_helper(transport);
 348         free(transport->data);
 349         return res;
 350 }
 351
 352 static int fetch_with_fetch(struct transport *transport,
 353                             int nr_heads, struct ref **to_fetch)
 354 {
 355         struct helper_data *data = transport->data;
 356         int i;
 357         struct strbuf buf = STRBUF_INIT;
 358
 359         for (i = 0; i < nr_heads; i++) {
 360                 const struct ref *posn = to_fetch[i];
 361                 if (posn->status & REF_STATUS_UPTODATE)
 362                         continue;
 363
 364                 strbuf_addf(&buf, "fetch %s %s\n",
 365                             oid_to_hex(&posn->old_oid),
 366                             posn->symref ? posn->symref : posn->name);
 367         }
 368
 369         strbuf_addch(&buf, '\n');
 370         sendline(data, &buf);
 371
 372         while (1) {
 373                 if (recvline(data, &buf))
 374                         exit(128);
 375
 376                 if (starts_with(buf.buf, "lock ")) {
 377                         const char *name = buf.buf + 5;
 378                         if (transport->pack_lockfile)
 379                                 warning("%s also locked %s", data->name, name);
 380                         else
 381                                 transport->pack_lockfile = xstrdup(name);
 382                 }
 383                 else if (data->check_connectivity &&
 384                          data->transport_options.check_self_contained_and_connected &&
 385                          !strcmp(buf.buf, "connectivity-ok"))
 386                         data->transport_options.self_contained_and_connected = 1;
 387                 else if (!buf.len)
 388                         break;
 389                 else
 390                         warning("%s unexpectedly said: '%s'", data->name, buf.buf);
 391         }
 392         strbuf_release(&buf);
 393         return 0;
 394 }
 395
 396 static int get_importer(struct transport *transport, struct child_process *fastimport)
 397 {
 398         struct child_process *helper = get_helper(transport);
 399         struct helper_data *data = transport->data;
 400         int cat_blob_fd, code;
 401         child_process_init(fastimport);
 402         fastimport->in = helper->out;
 403         argv_array_push(&fastimport->args, "fast-import");
 404         argv_array_push(&fastimport->args, debug ? "--stats" : "--quiet");
 405
 406         if (data->bidi_import) {
 407                 cat_blob_fd = xdup(helper->in);
 408                 argv_array_pushf(&fastimport->args, "--cat-blob-fd=%d", cat_blob_fd);
 409         }
 410         fastimport->git_cmd = 1;
 411
 412         code = start_command(fastimport);
 413         return code;
 414 }
 415
 416 static int get_exporter(struct transport *transport,
 417                         struct child_process *fastexport,
 418                         struct string_list *revlist_args)
 419 {
 420         struct helper_data *data = transport->data;
 421         struct child_process *helper = get_helper(transport);
 422         int i;
 423
 424         child_process_init(fastexport);
 425
 426         /* we need to duplicate helper->in because we want to use it after
 427          * fastexport is done with it. */
 428         fastexport->out = dup(helper->in);
 429         argv_array_push(&fastexport->args, "fast-export");
 430         argv_array_push(&fastexport->args, "--use-done-feature");
 431         argv_array_push(&fastexport->args, data->signed_tags ?
 432                 "--signed-tags=verbatim" : "--signed-tags=warn-strip");
 433         if (data->export_marks)
 434                 argv_array_pushf(&fastexport->args, "--export-marks=%s.tmp", data->export_marks);
 435         if (data->import_marks)
 436                 argv_array_pushf(&fastexport->args, "--import-marks=%s", data->import_marks);
 437
 438         for (i = 0; i < revlist_args->nr; i++)
 439                 argv_array_push(&fastexport->args, revlist_args->items[i].string);
 440
 441         fastexport->git_cmd = 1;
 442         return start_command(fastexport);
 443 }
 444
 445 static int fetch_with_import(struct transport *transport,
 446                              int nr_heads, struct ref **to_fetch)
 447 {
 448         struct child_process fastimport;
 449         struct helper_data *data = transport->data;
 450         int i;
 451         struct ref *posn;
 452         struct strbuf buf = STRBUF_INIT;
 453
 454         get_helper(transport);
 455
 456         if (get_importer(transport, &fastimport))
 457                 die("Couldn't run fast-import");
 458
 459         for (i = 0; i < nr_heads; i++) {
 460                 posn = to_fetch[i];
 461                 if (posn->status & REF_STATUS_UPTODATE)
 462                         continue;
 463
 464                 strbuf_addf(&buf, "import %s\n",
 465                             posn->symref ? posn->symref : posn->name);
 466                 sendline(data, &buf);
 467                 strbuf_reset(&buf);
 468         }
 469
 470         write_constant(data->helper->in, "\n");
 471         /*
 472          * remote-helpers that advertise the bidi-import capability are required to
 473          * buffer the complete batch of import commands until this newline before
 474          * sending data to fast-import.
 475          * These helpers read back data from fast-import on their stdin, which could
 476          * be mixed with import commands, otherwise.
 477          */
 478
 479         if (finish_command(&fastimport))
 480                 die("Error while running fast-import");
 481
 482         /*
 483          * The fast-import stream of a remote helper that advertises
 484          * the "refspec" capability writes to the refs named after the
 485          * right hand side of the first refspec matching each ref we
 486          * were fetching.
 487          *
 488          * (If no "refspec" capability was specified, for historical
 489          * reasons we default to the equivalent of *:*.)
 490          *
 491          * Store the result in to_fetch[i].old_sha1.  Callers such
 492          * as "git fetch" can use the value to write feedback to the
 493          * terminal, populate FETCH_HEAD, and determine what new value
 494          * should be written to peer_ref if the update is a
 495          * fast-forward or this is a forced update.
 496          */
 497         for (i = 0; i < nr_heads; i++) {
 498                 char *private, *name;
 499                 posn = to_fetch[i];
 500                 if (posn->status & REF_STATUS_UPTODATE)
 501                         continue;
 502                 name = posn->symref ? posn->symref : posn->name;
 503                 if (data->refspecs)
 504                         private = apply_refspecs(data->refspecs, data->refspec_nr, name);
 505                 else
 506                         private = xstrdup(name);
 507                 if (private) {
 508                         if (read_ref(private, posn->old_oid.hash) < 0)
 509                                 die("Could not read ref %s", private);
 510                         free(private);
 511                 }
 512         }
 513         strbuf_release(&buf);
 514         return 0;
 515 }
 516
 517 static int process_connect_service(struct transport *transport,
 518                                    const char *name, const char *exec)
 519 {
 520         struct helper_data *data = transport->data;
 521         struct strbuf cmdbuf = STRBUF_INIT;
 522         struct child_process *helper;
 523         int r, duped, ret = 0;
 524         FILE *input;
 525
 526         helper = get_helper(transport);
 527
 528         /*
 529          * Yes, dup the pipe another time, as we need unbuffered version
 530          * of input pipe as FILE*. fclose() closes the underlying fd and
 531          * stream buffering only can be changed before first I/O operation
 532          * on it.
 533          */
 534         duped = dup(helper->out);
 535         if (duped < 0)
 536                 die_errno("Can't dup helper output fd");
 537         input = xfdopen(duped, "r");
 538         setvbuf(input, NULL, _IONBF, 0);
 539
 540         /*
 541          * Handle --upload-pack and friends. This is fire and forget...
 542          * just warn if it fails.
 543          */
 544         if (strcmp(name, exec)) {
 545                 r = set_helper_option(transport, "servpath", exec);
 546                 if (r > 0)
 547                         warning("Setting remote service path not supported by protocol.");
 548                 else if (r < 0)
 549                         warning("Invalid remote service path.");
 550         }
 551
 552         if (data->connect)
 553                 strbuf_addf(&cmdbuf, "connect %s\n", name);
 554         else
 555                 goto exit;
 556
 557         sendline(data, &cmdbuf);
 558         if (recvline_fh(input, &cmdbuf, name))
 559                 exit(128);
 560
 561         if (!strcmp(cmdbuf.buf, "")) {
 562                 data->no_disconnect_req = 1;
 563                 if (debug)
 564                         fprintf(stderr, "Debug: Smart transport connection "
 565                                 "ready.\n");
 566                 ret = 1;
 567         } else if (!strcmp(cmdbuf.buf, "fallback")) {
 568                 if (debug)
 569                         fprintf(stderr, "Debug: Falling back to dumb "
 570                                 "transport.\n");
 571         } else
 572                 die("Unknown response to connect: %s",
 573                         cmdbuf.buf);
 574
 575 exit:
 576         fclose(input);
 577         return ret;
 578 }
 579
 580 static int process_connect(struct transport *transport,
 581                                      int for_push)
 582 {
 583         struct helper_data *data = transport->data;
 584         const char *name;
 585         const char *exec;
 586
 587         name = for_push ? "git-receive-pack" : "git-upload-pack";
 588         if (for_push)
 589                 exec = data->transport_options.receivepack;
 590         else
 591                 exec = data->transport_options.uploadpack;
 592
 593         return process_connect_service(transport, name, exec);
 594 }
 595
 596 static int connect_helper(struct transport *transport, const char *name,
 597                    const char *exec, int fd[2])
 598 {
 599         struct helper_data *data = transport->data;
 600
 601         /* Get_helper so connect is inited. */
 602         get_helper(transport);
 603         if (!data->connect)
 604                 die("Operation not supported by protocol.");
 605
 606         if (!process_connect_service(transport, name, exec))
 607                 die("Can't connect to subservice %s.", name);
 608
 609         fd[0] = data->helper->out;
 610         fd[1] = data->helper->in;
 611         return 0;
 612 }
 613
 614 static int fetch(struct transport *transport,
 615                  int nr_heads, struct ref **to_fetch)
 616 {
 617         struct helper_data *data = transport->data;
 618         int i, count;
 619
 620         if (process_connect(transport, 0)) {
 621                 do_take_over(transport);
 622                 return transport->fetch(transport, nr_heads, to_fetch);
 623         }
 624
 625         count = 0;
 626         for (i = 0; i < nr_heads; i++)
 627                 if (!(to_fetch[i]->status & REF_STATUS_UPTODATE))
 628                         count++;
 629
 630         if (!count)
 631                 return 0;
 632
 633         if (data->check_connectivity &&
 634             data->transport_options.check_self_contained_and_connected)
 635                 set_helper_option(transport, "check-connectivity", "true");
 636
 637         if (transport->cloning)
 638                 set_helper_option(transport, "cloning", "true");
 639
 640         if (data->transport_options.update_shallow)
 641                 set_helper_option(transport, "update-shallow", "true");
 642
 643         if (data->fetch)
 644                 return fetch_with_fetch(transport, nr_heads, to_fetch);
 645
 646         if (data->import)
 647                 return fetch_with_import(transport, nr_heads, to_fetch);
 648
 649         return -1;
 650 }
 651
 652 static int push_update_ref_status(struct strbuf *buf,
 653                                    struct ref **ref,
 654                                    struct ref *remote_refs)
 655 {
 656         char *refname, *msg;
 657         int status, forced = 0;
 658
 659         if (starts_with(buf->buf, "ok ")) {
 660                 status = REF_STATUS_OK;
 661                 refname = buf->buf + 3;
 662         } else if (starts_with(buf->buf, "error ")) {
 663                 status = REF_STATUS_REMOTE_REJECT;
 664                 refname = buf->buf + 6;
 665         } else
 666                 die("expected ok/error, helper said '%s'", buf->buf);
 667
 668         msg = strchr(refname, ' ');
 669         if (msg) {
 670                 struct strbuf msg_buf = STRBUF_INIT;
 671                 const char *end;
 672
 673                 *msg++ = '\0';
 674                 if (!unquote_c_style(&msg_buf, msg, &end))
 675                         msg = strbuf_detach(&msg_buf, NULL);
 676                 else
 677                         msg = xstrdup(msg);
 678                 strbuf_release(&msg_buf);
 679
 680                 if (!strcmp(msg, "no match")) {
 681                         status = REF_STATUS_NONE;
 682                         free(msg);
 683                         msg = NULL;
 684                 }
 685                 else if (!strcmp(msg, "up to date")) {
 686                         status = REF_STATUS_UPTODATE;
 687                         free(msg);
 688                         msg = NULL;
 689                 }
 690                 else if (!strcmp(msg, "non-fast forward")) {
 691                         status = REF_STATUS_REJECT_NONFASTFORWARD;
 692                         free(msg);
 693                         msg = NULL;
 694                 }
 695                 else if (!strcmp(msg, "already exists")) {
 696                         status = REF_STATUS_REJECT_ALREADY_EXISTS;
 697                         free(msg);
 698                         msg = NULL;
 699                 }
 700                 else if (!strcmp(msg, "fetch first")) {
 701                         status = REF_STATUS_REJECT_FETCH_FIRST;
 702                         free(msg);
 703                         msg = NULL;
 704                 }
 705                 else if (!strcmp(msg, "needs force")) {
 706                         status = REF_STATUS_REJECT_NEEDS_FORCE;
 707                         free(msg);
 708                         msg = NULL;
 709                 }
 710                 else if (!strcmp(msg, "stale info")) {
 711                         status = REF_STATUS_REJECT_STALE;
 712                         free(msg);
 713                         msg = NULL;
 714                 }
 715                 else if (!strcmp(msg, "forced update")) {
 716                         forced = 1;
 717                         free(msg);
 718                         msg = NULL;
 719                 }
 720         }
 721
 722         if (*ref)
 723                 *ref = find_ref_by_name(*ref, refname);
 724         if (!*ref)
 725                 *ref = find_ref_by_name(remote_refs, refname);
 726         if (!*ref) {
 727                 warning("helper reported unexpected status of %s", refname);
 728                 return 1;
 729         }
 730
 731         if ((*ref)->status != REF_STATUS_NONE) {
 732                 /*
 733                  * Earlier, the ref was marked not to be pushed, so ignore the ref
 734                  * status reported by the remote helper if the latter is 'no match'.
 735                  */
 736                 if (status == REF_STATUS_NONE)
 737                         return 1;
 738         }
 739
 740         (*ref)->status = status;
 741         (*ref)->forced_update |= forced;
 742         (*ref)->remote_status = msg;
 743         return !(status == REF_STATUS_OK);
 744 }
 745
 746 static int push_update_refs_status(struct helper_data *data,
 747                                     struct ref *remote_refs,
 748                                     int flags)
 749 {
 750         struct strbuf buf = STRBUF_INIT;
 751         struct ref *ref = remote_refs;
 752         int ret = 0;
 753
 754         for (;;) {
 755                 char *private;
 756
 757                 if (recvline(data, &buf)) {
 758                         ret = 1;
 759                         break;
 760                 }
 761
 762                 if (!buf.len)
 763                         break;
 764
 765                 if (push_update_ref_status(&buf, &ref, remote_refs))
 766                         continue;
 767
 768                 if (flags & TRANSPORT_PUSH_DRY_RUN || !data->refspecs || data->no_private_update)
 769                         continue;
 770
 771                 /* propagate back the update to the remote namespace */
 772                 private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
 773                 if (!private)
 774                         continue;
 775                 update_ref("update by helper", private, ref->new_oid.hash, NULL, 0, 0);
 776                 free(private);
 777         }
 778         strbuf_release(&buf);
 779         return ret;
 780 }
 781
 782 static void set_common_push_options(struct transport *transport,
 783                                    const char *name, int flags)
 784 {
 785         if (flags & TRANSPORT_PUSH_DRY_RUN) {
 786                 if (set_helper_option(transport, "dry-run", "true") != 0)
 787                         die("helper %s does not support dry-run", name);
 788         } else if (flags & TRANSPORT_PUSH_CERT_ALWAYS) {
 789                 if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "true") != 0)
 790                         die("helper %s does not support --signed", name);
 791         } else if (flags & TRANSPORT_PUSH_CERT_IF_ASKED) {
 792                 if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "if-asked") != 0)
 793                         die("helper %s does not support --signed=if-asked", name);
 794         }
 795 }
 796
 797 static int push_refs_with_push(struct transport *transport,
 798                                struct ref *remote_refs, int flags)
 799 {
 800         int force_all = flags & TRANSPORT_PUSH_FORCE;
 801         int mirror = flags & TRANSPORT_PUSH_MIRROR;
 802         struct helper_data *data = transport->data;
 803         struct strbuf buf = STRBUF_INIT;
 804         struct ref *ref;
 805         struct string_list cas_options = STRING_LIST_INIT_DUP;
 806         struct string_list_item *cas_option;
 807
 808         get_helper(transport);
 809         if (!data->push)
 810                 return 1;
 811
 812         for (ref = remote_refs; ref; ref = ref->next) {
 813                 if (!ref->peer_ref && !mirror)
 814                         continue;
 815
 816                 /* Check for statuses set by set_ref_status_for_push() */
 817                 switch (ref->status) {
 818                 case REF_STATUS_REJECT_NONFASTFORWARD:
 819                 case REF_STATUS_REJECT_STALE:
 820                 case REF_STATUS_REJECT_ALREADY_EXISTS:
 821                 case REF_STATUS_UPTODATE:
 822                         continue;
 823                 default:
 824                         ; /* do nothing */
 825                 }
 826
 827                 if (force_all)
 828                         ref->force = 1;
 829
 830                 strbuf_addstr(&buf, "push ");
 831                 if (!ref->deletion) {
 832                         if (ref->force)
 833                                 strbuf_addch(&buf, '+');
 834                         if (ref->peer_ref)
 835                                 strbuf_addstr(&buf, ref->peer_ref->name);
 836                         else
 837                                 strbuf_addstr(&buf, oid_to_hex(&ref->new_oid));
 838                 }
 839                 strbuf_addch(&buf, ':');
 840                 strbuf_addstr(&buf, ref->name);
 841                 strbuf_addch(&buf, '\n');
 842
 843                 /*
 844                  * The "--force-with-lease" options without explicit
 845                  * values to expect have already been expanded into
 846                  * the ref->old_oid_expect[] field; we can ignore
 847                  * transport->smart_options->cas altogether and instead
 848                  * can enumerate them from the refs.
 849                  */
 850                 if (ref->expect_old_sha1) {
 851                         struct strbuf cas = STRBUF_INIT;
 852                         strbuf_addf(&cas, "%s:%s",
 853                                     ref->name, oid_to_hex(&ref->old_oid_expect));
 854                         string_list_append(&cas_options, strbuf_detach(&cas, NULL));
 855                 }
 856         }
 857         if (buf.len == 0) {
 858                 string_list_clear(&cas_options, 0);
 859                 return 0;
 860         }
 861
 862         for_each_string_list_item(cas_option, &cas_options)
 863                 set_helper_option(transport, "cas", cas_option->string);
 864         set_common_push_options(transport, data->name, flags);
 865
 866         strbuf_addch(&buf, '\n');
 867         sendline(data, &buf);
 868         strbuf_release(&buf);
 869
 870         return push_update_refs_status(data, remote_refs, flags);
 871 }
 872
 873 static int push_refs_with_export(struct transport *transport,
 874                 struct ref *remote_refs, int flags)
 875 {
 876         struct ref *ref;
 877         struct child_process *helper, exporter;
 878         struct helper_data *data = transport->data;
 879         struct string_list revlist_args = STRING_LIST_INIT_DUP;
 880         struct strbuf buf = STRBUF_INIT;
 881
 882         if (!data->refspecs)
 883                 die("remote-helper doesn't support push; refspec needed");
 884
 885         set_common_push_options(transport, data->name, flags);
 886         if (flags & TRANSPORT_PUSH_FORCE) {
 887                 if (set_helper_option(transport, "force", "true") != 0)
 888                         warning("helper %s does not support 'force'", data->name);
 889         }
 890
 891         helper = get_helper(transport);
 892
 893         write_constant(helper->in, "export\n");
 894
 895         for (ref = remote_refs; ref; ref = ref->next) {
 896                 char *private;
 897                 struct object_id oid;
 898
 899                 private = apply_refspecs(data->refspecs, data->refspec_nr, ref->name);
 900                 if (private && !get_sha1(private, oid.hash)) {
 901                         strbuf_addf(&buf, "^%s", private);
 902                         string_list_append(&revlist_args, strbuf_detach(&buf, NULL));
 903                         oidcpy(&ref->old_oid, &oid);
 904                 }
 905                 free(private);
 906
 907                 if (ref->peer_ref) {
 908                         if (strcmp(ref->name, ref->peer_ref->name)) {
 909                                 if (!ref->deletion) {
 910                                         const char *name;
 911                                         int flag;
 912
 913                                         /* Follow symbolic refs (mainly for HEAD). */
 914                                         name = resolve_ref_unsafe(
 915                                                  ref->peer_ref->name,
 916                                                  RESOLVE_REF_READING,
 917                                                  oid.hash, &flag);
 918                                         if (!name || !(flag & REF_ISSYMREF))
 919                                                 name = ref->peer_ref->name;
 920
 921                                         strbuf_addf(&buf, "%s:%s", name, ref->name);
 922                                 } else
 923                                         strbuf_addf(&buf, ":%s", ref->name);
 924
 925                                 string_list_append(&revlist_args, "--refspec");
 926                                 string_list_append(&revlist_args, buf.buf);
 927                                 strbuf_release(&buf);
 928                         }
 929                         if (!ref->deletion)
 930                                 string_list_append(&revlist_args, ref->peer_ref->name);
 931                 }
 932         }
 933
 934         if (get_exporter(transport, &exporter, &revlist_args))
 935                 die("Couldn't run fast-export");
 936
 937         string_list_clear(&revlist_args, 1);
 938
 939         if (finish_command(&exporter))
 940                 die("Error while running fast-export");
 941         if (push_update_refs_status(data, remote_refs, flags))
 942                 return 1;
 943
 944         if (data->export_marks) {
 945                 strbuf_addf(&buf, "%s.tmp", data->export_marks);
 946                 rename(buf.buf, data->export_marks);
 947                 strbuf_release(&buf);
 948         }
 949
 950         return 0;
 951 }
 952
 953 static int push_refs(struct transport *transport,
 954                 struct ref *remote_refs, int flags)
 955 {
 956         struct helper_data *data = transport->data;
 957
 958         if (process_connect(transport, 1)) {
 959                 do_take_over(transport);
 960                 return transport->push_refs(transport, remote_refs, flags);
 961         }
 962
 963         if (!remote_refs) {
 964                 fprintf(stderr, "No refs in common and none specified; doing nothing.\n"
 965                         "Perhaps you should specify a branch such as 'master'.\n");
 966                 return 0;
 967         }
 968
 969         if (data->push)
 970                 return push_refs_with_push(transport, remote_refs, flags);
 971
 972         if (data->export)
 973                 return push_refs_with_export(transport, remote_refs, flags);
 974
 975         return -1;
 976 }
 977
 978
 979 static int has_attribute(const char *attrs, const char *attr) {
 980         int len;
 981         if (!attrs)
 982                 return 0;
 983
 984         len = strlen(attr);
 985         for (;;) {
 986                 const char *space = strchrnul(attrs, ' ');
 987                 if (len == space - attrs && !strncmp(attrs, attr, len))
 988                         return 1;
 989                 if (!*space)
 990                         return 0;
 991                 attrs = space + 1;
 992         }
 993 }
 994
 995 static struct ref *get_refs_list(struct transport *transport, int for_push)
 996 {
 997         struct helper_data *data = transport->data;
 998         struct child_process *helper;
 999         struct ref *ret = NULL;
1000         struct ref **tail = &ret;
1001         struct ref *posn;
1002         struct strbuf buf = STRBUF_INIT;
1003
1004         helper = get_helper(transport);
1005
1006         if (process_connect(transport, for_push)) {
1007                 do_take_over(transport);
1008                 return transport->get_refs_list(transport, for_push);
1009         }
1010
1011         if (data->push && for_push)
1012                 write_str_in_full(helper->in, "list for-push\n");
1013         else
1014                 write_str_in_full(helper->in, "list\n");
1015
1016         while (1) {
1017                 char *eov, *eon;
1018                 if (recvline(data, &buf))
1019                         exit(128);
1020
1021                 if (!*buf.buf)
1022                         break;
1023
1024                 eov = strchr(buf.buf, ' ');
1025                 if (!eov)
1026                         die("Malformed response in ref list: %s", buf.buf);
1027                 eon = strchr(eov + 1, ' ');
1028                 *eov = '\0';
1029                 if (eon)
1030                         *eon = '\0';
1031                 *tail = alloc_ref(eov + 1);
1032                 if (buf.buf[0] == '@')
1033                         (*tail)->symref = xstrdup(buf.buf + 1);
1034                 else if (buf.buf[0] != '?')
1035                         get_oid_hex(buf.buf, &(*tail)->old_oid);
1036                 if (eon) {
1037                         if (has_attribute(eon + 1, "unchanged")) {
1038                                 (*tail)->status |= REF_STATUS_UPTODATE;
1039                                 if (read_ref((*tail)->name,
1040                                              (*tail)->old_oid.hash) < 0)
1041                                         die(_("Could not read ref %s"),
1042                                             (*tail)->name);
1043                         }
1044                 }
1045                 tail = &((*tail)->next);
1046         }
1047         if (debug)
1048                 fprintf(stderr, "Debug: Read ref listing.\n");
1049         strbuf_release(&buf);
1050
1051         for (posn = ret; posn; posn = posn->next)
1052                 resolve_remote_symref(posn, ret);
1053
1054         return ret;
1055 }
1056
1057 int transport_helper_init(struct transport *transport, const char *name)
1058 {
1059         struct helper_data *data = xcalloc(1, sizeof(*data));
1060         data->name = name;
1061
1062         transport_check_allowed(name);
1063
1064         if (getenv("GIT_TRANSPORT_HELPER_DEBUG"))
1065                 debug = 1;
1066
1067         transport->data = data;
1068         transport->set_option = set_helper_option;
1069         transport->get_refs_list = get_refs_list;
1070         transport->fetch = fetch;
1071         transport->push_refs = push_refs;
1072         transport->disconnect = release_helper;
1073         transport->connect = connect_helper;
1074         transport->smart_options = &(data->transport_options);
1075         return 0;
1076 }
1077
1078 /*
1079  * Linux pipes can buffer 65536 bytes at once (and most platforms can
1080  * buffer less), so attempt reads and writes with up to that size.
1081  */
1082 #define BUFFERSIZE 65536
1083 /* This should be enough to hold debugging message. */
1084 #define PBUFFERSIZE 8192
1085
1086 /* Print bidirectional transfer loop debug message. */
1087 __attribute__((format (printf, 1, 2)))
1088 static void transfer_debug(const char *fmt, ...)
1089 {
1090         va_list args;
1091         char msgbuf[PBUFFERSIZE];
1092         static int debug_enabled = -1;
1093
1094         if (debug_enabled < 0)
1095                 debug_enabled = getenv("GIT_TRANSLOOP_DEBUG") ? 1 : 0;
1096         if (!debug_enabled)
1097                 return;
1098
1099         va_start(args, fmt);
1100         vsnprintf(msgbuf, PBUFFERSIZE, fmt, args);
1101         va_end(args);
1102         fprintf(stderr, "Transfer loop debugging: %s\n", msgbuf);
1103 }
1104
1105 /* Stream state: More data may be coming in this direction. */
1106 #define SSTATE_TRANSFERRING 0
1107 /*
1108  * Stream state: No more data coming in this direction, flushing rest of
1109  * data.
1110  */
1111 #define SSTATE_FLUSHING 1
1112 /* Stream state: Transfer in this direction finished. */
1113 #define SSTATE_FINISHED 2
1114
1115 #define STATE_NEEDS_READING(state) ((state) <= SSTATE_TRANSFERRING)
1116 #define STATE_NEEDS_WRITING(state) ((state) <= SSTATE_FLUSHING)
1117 #define STATE_NEEDS_CLOSING(state) ((state) == SSTATE_FLUSHING)
1118
1119 /* Unidirectional transfer. */
1120 struct unidirectional_transfer {
1121         /* Source */
1122         int src;
1123         /* Destination */
1124         int dest;
1125         /* Is source socket? */
1126         int src_is_sock;
1127         /* Is destination socket? */
1128         int dest_is_sock;
1129         /* Transfer state (TRANSFERRING/FLUSHING/FINISHED) */
1130         int state;
1131         /* Buffer. */
1132         char buf[BUFFERSIZE];
1133         /* Buffer used. */
1134         size_t bufuse;
1135         /* Name of source. */
1136         const char *src_name;
1137         /* Name of destination. */
1138         const char *dest_name;
1139 };
1140
1141 /* Closes the target (for writing) if transfer has finished. */
1142 static void udt_close_if_finished(struct unidirectional_transfer *t)
1143 {
1144         if (STATE_NEEDS_CLOSING(t->state) && !t->bufuse) {
1145                 t->state = SSTATE_FINISHED;
1146                 if (t->dest_is_sock)
1147                         shutdown(t->dest, SHUT_WR);
1148                 else
1149                         close(t->dest);
1150                 transfer_debug("Closed %s.", t->dest_name);
1151         }
1152 }
1153
1154 /*
1155  * Tries to read data from source into buffer. If buffer is full,
1156  * no data is read. Returns 0 on success, -1 on error.
1157  */
1158 static int udt_do_read(struct unidirectional_transfer *t)
1159 {
1160         ssize_t bytes;
1161
1162         if (t->bufuse == BUFFERSIZE)
1163                 return 0;       /* No space for more. */
1164
1165         transfer_debug("%s is readable", t->src_name);
1166         bytes = read(t->src, t->buf + t->bufuse, BUFFERSIZE - t->bufuse);
1167         if (bytes < 0 && errno != EWOULDBLOCK && errno != EAGAIN &&
1168                 errno != EINTR) {
1169                 error_errno("read(%s) failed", t->src_name);
1170                 return -1;
1171         } else if (bytes == 0) {
1172                 transfer_debug("%s EOF (with %i bytes in buffer)",
1173                         t->src_name, (int)t->bufuse);
1174                 t->state = SSTATE_FLUSHING;
1175         } else if (bytes > 0) {
1176                 t->bufuse += bytes;
1177                 transfer_debug("Read %i bytes from %s (buffer now at %i)",
1178                         (int)bytes, t->src_name, (int)t->bufuse);
1179         }
1180         return 0;
1181 }
1182
1183 /* Tries to write data from buffer into destination. If buffer is empty,
1184  * no data is written. Returns 0 on success, -1 on error.
1185  */
1186 static int udt_do_write(struct unidirectional_transfer *t)
1187 {
1188         ssize_t bytes;
1189
1190         if (t->bufuse == 0)
1191                 return 0;       /* Nothing to write. */
1192
1193         transfer_debug("%s is writable", t->dest_name);
1194         bytes = xwrite(t->dest, t->buf, t->bufuse);
1195         if (bytes < 0 && errno != EWOULDBLOCK) {
1196                 error_errno("write(%s) failed", t->dest_name);
1197                 return -1;
1198         } else if (bytes > 0) {
1199                 t->bufuse -= bytes;
1200                 if (t->bufuse)
1201                         memmove(t->buf, t->buf + bytes, t->bufuse);
1202                 transfer_debug("Wrote %i bytes to %s (buffer now at %i)",
1203                         (int)bytes, t->dest_name, (int)t->bufuse);
1204         }
1205         return 0;
1206 }
1207
1208
1209 /* State of bidirectional transfer loop. */
1210 struct bidirectional_transfer_state {
1211         /* Direction from program to git. */
1212         struct unidirectional_transfer ptg;
1213         /* Direction from git to program. */
1214         struct unidirectional_transfer gtp;
1215 };
1216
1217 static void *udt_copy_task_routine(void *udt)
1218 {
1219         struct unidirectional_transfer *t = (struct unidirectional_transfer *)udt;
1220         while (t->state != SSTATE_FINISHED) {
1221                 if (STATE_NEEDS_READING(t->state))
1222                         if (udt_do_read(t))
1223                                 return NULL;
1224                 if (STATE_NEEDS_WRITING(t->state))
1225                         if (udt_do_write(t))
1226                                 return NULL;
1227                 if (STATE_NEEDS_CLOSING(t->state))
1228                         udt_close_if_finished(t);
1229         }
1230         return udt;     /* Just some non-NULL value. */
1231 }
1232
1233 #ifndef NO_PTHREADS
1234
1235 /*
1236  * Join thread, with appropriate errors on failure. Name is name for the
1237  * thread (for error messages). Returns 0 on success, 1 on failure.
1238  */
1239 static int tloop_join(pthread_t thread, const char *name)
1240 {
1241         int err;
1242         void *tret;
1243         err = pthread_join(thread, &tret);
1244         if (!tret) {
1245                 error("%s thread failed", name);
1246                 return 1;
1247         }
1248         if (err) {
1249                 error("%s thread failed to join: %s", name, strerror(err));
1250                 return 1;
1251         }
1252         return 0;
1253 }
1254
1255 /*
1256  * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1257  * -1 on failure.
1258  */
1259 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1260 {
1261         pthread_t gtp_thread;
1262         pthread_t ptg_thread;
1263         int err;
1264         int ret = 0;
1265         err = pthread_create(&gtp_thread, NULL, udt_copy_task_routine,
1266                 &s->gtp);
1267         if (err)
1268                 die("Can't start thread for copying data: %s", strerror(err));
1269         err = pthread_create(&ptg_thread, NULL, udt_copy_task_routine,
1270                 &s->ptg);
1271         if (err)
1272                 die("Can't start thread for copying data: %s", strerror(err));
1273
1274         ret |= tloop_join(gtp_thread, "Git to program copy");
1275         ret |= tloop_join(ptg_thread, "Program to git copy");
1276         return ret;
1277 }
1278 #else
1279
1280 /* Close the source and target (for writing) for transfer. */
1281 static void udt_kill_transfer(struct unidirectional_transfer *t)
1282 {
1283         t->state = SSTATE_FINISHED;
1284         /*
1285          * Socket read end left open isn't a disaster if nobody
1286          * attempts to read from it (mingw compat headers do not
1287          * have SHUT_RD)...
1288          *
1289          * We can't fully close the socket since otherwise gtp
1290          * task would first close the socket it sends data to
1291          * while closing the ptg file descriptors.
1292          */
1293         if (!t->src_is_sock)
1294                 close(t->src);
1295         if (t->dest_is_sock)
1296                 shutdown(t->dest, SHUT_WR);
1297         else
1298                 close(t->dest);
1299 }
1300
1301 /*
1302  * Join process, with appropriate errors on failure. Name is name for the
1303  * process (for error messages). Returns 0 on success, 1 on failure.
1304  */
1305 static int tloop_join(pid_t pid, const char *name)
1306 {
1307         int tret;
1308         if (waitpid(pid, &tret, 0) < 0) {
1309                 error_errno("%s process failed to wait", name);
1310                 return 1;
1311         }
1312         if (!WIFEXITED(tret) || WEXITSTATUS(tret)) {
1313                 error("%s process failed", name);
1314                 return 1;
1315         }
1316         return 0;
1317 }
1318
1319 /*
1320  * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1321  * -1 on failure.
1322  */
1323 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1324 {
1325         pid_t pid1, pid2;
1326         int ret = 0;
1327
1328         /* Fork thread #1: git to program. */
1329         pid1 = fork();
1330         if (pid1 < 0)
1331                 die_errno("Can't start thread for copying data");
1332         else if (pid1 == 0) {
1333                 udt_kill_transfer(&s->ptg);
1334                 exit(udt_copy_task_routine(&s->gtp) ? 0 : 1);
1335         }
1336
1337         /* Fork thread #2: program to git. */
1338         pid2 = fork();
1339         if (pid2 < 0)
1340                 die_errno("Can't start thread for copying data");
1341         else if (pid2 == 0) {
1342                 udt_kill_transfer(&s->gtp);
1343                 exit(udt_copy_task_routine(&s->ptg) ? 0 : 1);
1344         }
1345
1346         /*
1347          * Close both streams in parent as to not interfere with
1348          * end of file detection and wait for both tasks to finish.
1349          */
1350         udt_kill_transfer(&s->gtp);
1351         udt_kill_transfer(&s->ptg);
1352         ret |= tloop_join(pid1, "Git to program copy");
1353         ret |= tloop_join(pid2, "Program to git copy");
1354         return ret;
1355 }
1356 #endif
1357
1358 /*
1359  * Copies data from stdin to output and from input to stdout simultaneously.
1360  * Additionally filtering through given filter. If filter is NULL, uses
1361  * identity filter.
1362  */
1363 int bidirectional_transfer_loop(int input, int output)
1364 {
1365         struct bidirectional_transfer_state state;
1366
1367         /* Fill the state fields. */
1368         state.ptg.src = input;
1369         state.ptg.dest = 1;
1370         state.ptg.src_is_sock = (input == output);
1371         state.ptg.dest_is_sock = 0;
1372         state.ptg.state = SSTATE_TRANSFERRING;
1373         state.ptg.bufuse = 0;
1374         state.ptg.src_name = "remote input";
1375         state.ptg.dest_name = "stdout";
1376
1377         state.gtp.src = 0;
1378         state.gtp.dest = output;
1379         state.gtp.src_is_sock = 0;
1380         state.gtp.dest_is_sock = (input == output);
1381         state.gtp.state = SSTATE_TRANSFERRING;
1382         state.gtp.bufuse = 0;
1383         state.gtp.src_name = "stdin";
1384         state.gtp.dest_name = "remote output";
1385
1386         return tloop_spawnwait_tasks(&state);
1387 }