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 #include "refspec.h"
  15 #include "transport-internal.h"
  16 #include "protocol.h"
  17
  18 static int debug;
  19
  20 struct 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                 object_format : 1;
  37
  38         /*
  39          * As an optimization, the transport code may invoke fetch before
  40          * get_refs_list. If this happens, and if the transport helper doesn't
  41          * support connect or stateless_connect, we need to invoke
  42          * get_refs_list ourselves if we haven't already done so. Keep track of
  43          * whether we have invoked get_refs_list.
  44          */
  45         unsigned get_refs_list_called : 1;
  46
  47         char *export_marks;
  48         char *import_marks;
  49         /* These go from remote name (as in "list") to private name */
  50         struct refspec rs;
  51         /* Transport options for fetch-pack/send-pack (should one of
  52          * those be invoked).
  53          */
  54         struct git_transport_options transport_options;
  55 };
  56
  57 static void sendline(struct helper_data *helper, struct strbuf *buffer)
  58 {
  59         if (debug)
  60                 fprintf(stderr, "Debug: Remote helper: -> %s", buffer->buf);
  61         if (write_in_full(helper->helper->in, buffer->buf, buffer->len) < 0)
  62                 die_errno(_("full write to remote helper failed"));
  63 }
  64
  65 static int recvline_fh(FILE *helper, struct strbuf *buffer)
  66 {
  67         strbuf_reset(buffer);
  68         if (debug)
  69                 fprintf(stderr, "Debug: Remote helper: Waiting...\n");
  70         if (strbuf_getline(buffer, helper) == EOF) {
  71                 if (debug)
  72                         fprintf(stderr, "Debug: Remote helper quit.\n");
  73                 return 1;
  74         }
  75
  76         if (debug)
  77                 fprintf(stderr, "Debug: Remote helper: <- %s\n", buffer->buf);
  78         return 0;
  79 }
  80
  81 static int recvline(struct helper_data *helper, struct strbuf *buffer)
  82 {
  83         return recvline_fh(helper->out, buffer);
  84 }
  85
  86 static void write_constant(int fd, const char *str)
  87 {
  88         if (debug)
  89                 fprintf(stderr, "Debug: Remote helper: -> %s", str);
  90         if (write_in_full(fd, str, strlen(str)) < 0)
  91                 die_errno(_("full write to remote helper failed"));
  92 }
  93
  94 static const char *remove_ext_force(const char *url)
  95 {
  96         if (url) {
  97                 const char *colon = strchr(url, ':');
  98                 if (colon && colon[1] == ':')
  99                         return colon + 2;
 100         }
 101         return url;
 102 }
 103
 104 static void do_take_over(struct transport *transport)
 105 {
 106         struct helper_data *data;
 107         data = (struct helper_data *)transport->data;
 108         transport_take_over(transport, data->helper);
 109         fclose(data->out);
 110         free(data);
 111 }
 112
 113 static void standard_options(struct transport *t);
 114
 115 static struct child_process *get_helper(struct transport *transport)
 116 {
 117         struct helper_data *data = transport->data;
 118         struct strbuf buf = STRBUF_INIT;
 119         struct child_process *helper;
 120         int duped;
 121         int code;
 122
 123         if (data->helper)
 124                 return data->helper;
 125
 126         helper = xmalloc(sizeof(*helper));
 127         child_process_init(helper);
 128         helper->in = -1;
 129         helper->out = -1;
 130         helper->err = 0;
 131         argv_array_pushf(&helper->args, "git-remote-%s", data->name);
 132         argv_array_push(&helper->args, transport->remote->name);
 133         argv_array_push(&helper->args, remove_ext_force(transport->url));
 134         helper->git_cmd = 0;
 135         helper->silent_exec_failure = 1;
 136
 137         if (have_git_dir())
 138                 argv_array_pushf(&helper->env_array, "%s=%s",
 139                                  GIT_DIR_ENVIRONMENT, get_git_dir());
 140
 141         helper->trace2_child_class = helper->args.argv[0]; /* "remote-<name>" */
 142
 143         code = start_command(helper);
 144         if (code < 0 && errno == ENOENT)
 145                 die(_("unable to find remote helper for '%s'"), data->name);
 146         else if (code != 0)
 147                 exit(code);
 148
 149         data->helper = helper;
 150         data->no_disconnect_req = 0;
 151         refspec_init(&data->rs, REFSPEC_FETCH);
 152
 153         /*
 154          * Open the output as FILE* so strbuf_getline_*() family of
 155          * functions can be used.
 156          * Do this with duped fd because fclose() will close the fd,
 157          * and stuff like taking over will require the fd to remain.
 158          */
 159         duped = dup(helper->out);
 160         if (duped < 0)
 161                 die_errno(_("can't dup helper output fd"));
 162         data->out = xfdopen(duped, "r");
 163
 164         write_constant(helper->in, "capabilities\n");
 165
 166         while (1) {
 167                 const char *capname, *arg;
 168                 int mandatory = 0;
 169                 if (recvline(data, &buf))
 170                         exit(128);
 171
 172                 if (!*buf.buf)
 173                         break;
 174
 175                 if (*buf.buf == '*') {
 176                         capname = buf.buf + 1;
 177                         mandatory = 1;
 178                 } else
 179                         capname = buf.buf;
 180
 181                 if (debug)
 182                         fprintf(stderr, "Debug: Got cap %s\n", capname);
 183                 if (!strcmp(capname, "fetch"))
 184                         data->fetch = 1;
 185                 else if (!strcmp(capname, "option"))
 186                         data->option = 1;
 187                 else if (!strcmp(capname, "push"))
 188                         data->push = 1;
 189                 else if (!strcmp(capname, "import"))
 190                         data->import = 1;
 191                 else if (!strcmp(capname, "bidi-import"))
 192                         data->bidi_import = 1;
 193                 else if (!strcmp(capname, "export"))
 194                         data->export = 1;
 195                 else if (!strcmp(capname, "check-connectivity"))
 196                         data->check_connectivity = 1;
 197                 else if (skip_prefix(capname, "refspec ", &arg)) {
 198                         refspec_append(&data->rs, arg);
 199                 } else if (!strcmp(capname, "connect")) {
 200                         data->connect = 1;
 201                 } else if (!strcmp(capname, "stateless-connect")) {
 202                         data->stateless_connect = 1;
 203                 } else if (!strcmp(capname, "signed-tags")) {
 204                         data->signed_tags = 1;
 205                 } else if (skip_prefix(capname, "export-marks ", &arg)) {
 206                         data->export_marks = xstrdup(arg);
 207                 } else if (skip_prefix(capname, "import-marks ", &arg)) {
 208                         data->import_marks = xstrdup(arg);
 209                 } else if (starts_with(capname, "no-private-update")) {
 210                         data->no_private_update = 1;
 211                 } else if (starts_with(capname, "object-format")) {
 212                         data->object_format = 1;
 213                 } else if (mandatory) {
 214                         die(_("unknown mandatory capability %s; this remote "
 215                               "helper probably needs newer version of Git"),
 216                             capname);
 217                 }
 218         }
 219         if (!data->rs.nr && (data->import || data->bidi_import || data->export)) {
 220                 warning(_("this remote helper should implement refspec capability"));
 221         }
 222         strbuf_release(&buf);
 223         if (debug)
 224                 fprintf(stderr, "Debug: Capabilities complete.\n");
 225         standard_options(transport);
 226         return data->helper;
 227 }
 228
 229 static int disconnect_helper(struct transport *transport)
 230 {
 231         struct helper_data *data = transport->data;
 232         int res = 0;
 233
 234         if (data->helper) {
 235                 if (debug)
 236                         fprintf(stderr, "Debug: Disconnecting.\n");
 237                 if (!data->no_disconnect_req) {
 238                         /*
 239                          * Ignore write errors; there's nothing we can do,
 240                          * since we're about to close the pipe anyway. And the
 241                          * most likely error is EPIPE due to the helper dying
 242                          * to report an error itself.
 243                          */
 244                         sigchain_push(SIGPIPE, SIG_IGN);
 245                         xwrite(data->helper->in, "\n", 1);
 246                         sigchain_pop(SIGPIPE);
 247                 }
 248                 close(data->helper->in);
 249                 close(data->helper->out);
 250                 fclose(data->out);
 251                 res = finish_command(data->helper);
 252                 FREE_AND_NULL(data->helper);
 253         }
 254         return res;
 255 }
 256
 257 static const char *unsupported_options[] = {
 258         TRANS_OPT_UPLOADPACK,
 259         TRANS_OPT_RECEIVEPACK,
 260         TRANS_OPT_THIN,
 261         TRANS_OPT_KEEP
 262         };
 263
 264 static const char *boolean_options[] = {
 265         TRANS_OPT_THIN,
 266         TRANS_OPT_KEEP,
 267         TRANS_OPT_FOLLOWTAGS,
 268         TRANS_OPT_DEEPEN_RELATIVE
 269         };
 270
 271 static int strbuf_set_helper_option(struct helper_data *data,
 272                                     struct strbuf *buf)
 273 {
 274         int ret;
 275
 276         sendline(data, buf);
 277         if (recvline(data, buf))
 278                 exit(128);
 279
 280         if (!strcmp(buf->buf, "ok"))
 281                 ret = 0;
 282         else if (starts_with(buf->buf, "error"))
 283                 ret = -1;
 284         else if (!strcmp(buf->buf, "unsupported"))
 285                 ret = 1;
 286         else {
 287                 warning(_("%s unexpectedly said: '%s'"), data->name, buf->buf);
 288                 ret = 1;
 289         }
 290         return ret;
 291 }
 292
 293 static int string_list_set_helper_option(struct helper_data *data,
 294                                          const char *name,
 295                                          struct string_list *list)
 296 {
 297         struct strbuf buf = STRBUF_INIT;
 298         int i, ret = 0;
 299
 300         for (i = 0; i < list->nr; i++) {
 301                 strbuf_addf(&buf, "option %s ", name);
 302                 quote_c_style(list->items[i].string, &buf, NULL, 0);
 303                 strbuf_addch(&buf, '\n');
 304
 305                 if ((ret = strbuf_set_helper_option(data, &buf)))
 306                         break;
 307                 strbuf_reset(&buf);
 308         }
 309         strbuf_release(&buf);
 310         return ret;
 311 }
 312
 313 static int set_helper_option(struct transport *transport,
 314                           const char *name, const char *value)
 315 {
 316         struct helper_data *data = transport->data;
 317         struct strbuf buf = STRBUF_INIT;
 318         int i, ret, is_bool = 0;
 319
 320         get_helper(transport);
 321
 322         if (!data->option)
 323                 return 1;
 324
 325         if (!strcmp(name, "deepen-not"))
 326                 return string_list_set_helper_option(data, name,
 327                                                      (struct string_list *)value);
 328
 329         for (i = 0; i < ARRAY_SIZE(unsupported_options); i++) {
 330                 if (!strcmp(name, unsupported_options[i]))
 331                         return 1;
 332         }
 333
 334         for (i = 0; i < ARRAY_SIZE(boolean_options); i++) {
 335                 if (!strcmp(name, boolean_options[i])) {
 336                         is_bool = 1;
 337                         break;
 338                 }
 339         }
 340
 341         strbuf_addf(&buf, "option %s ", name);
 342         if (is_bool)
 343                 strbuf_addstr(&buf, value ? "true" : "false");
 344         else
 345                 quote_c_style(value, &buf, NULL, 0);
 346         strbuf_addch(&buf, '\n');
 347
 348         ret = strbuf_set_helper_option(data, &buf);
 349         strbuf_release(&buf);
 350         return ret;
 351 }
 352
 353 static void standard_options(struct transport *t)
 354 {
 355         char buf[16];
 356         int v = t->verbose;
 357
 358         set_helper_option(t, "progress", t->progress ? "true" : "false");
 359
 360         xsnprintf(buf, sizeof(buf), "%d", v + 1);
 361         set_helper_option(t, "verbosity", buf);
 362
 363         switch (t->family) {
 364         case TRANSPORT_FAMILY_ALL:
 365                 /*
 366                  * this is already the default,
 367                  * do not break old remote helpers by setting "all" here
 368                  */
 369                 break;
 370         case TRANSPORT_FAMILY_IPV4:
 371                 set_helper_option(t, "family", "ipv4");
 372                 break;
 373         case TRANSPORT_FAMILY_IPV6:
 374                 set_helper_option(t, "family", "ipv6");
 375                 break;
 376         }
 377 }
 378
 379 static int release_helper(struct transport *transport)
 380 {
 381         int res = 0;
 382         struct helper_data *data = transport->data;
 383         refspec_clear(&data->rs);
 384         res = disconnect_helper(transport);
 385         free(transport->data);
 386         return res;
 387 }
 388
 389 static int fetch_with_fetch(struct transport *transport,
 390                             int nr_heads, struct ref **to_fetch)
 391 {
 392         struct helper_data *data = transport->data;
 393         int i;
 394         struct strbuf buf = STRBUF_INIT;
 395
 396         for (i = 0; i < nr_heads; i++) {
 397                 const struct ref *posn = to_fetch[i];
 398                 if (posn->status & REF_STATUS_UPTODATE)
 399                         continue;
 400
 401                 strbuf_addf(&buf, "fetch %s %s\n",
 402                             oid_to_hex(&posn->old_oid),
 403                             posn->symref ? posn->symref : posn->name);
 404         }
 405
 406         strbuf_addch(&buf, '\n');
 407         sendline(data, &buf);
 408
 409         while (1) {
 410                 const char *name;
 411
 412                 if (recvline(data, &buf))
 413                         exit(128);
 414
 415                 if (skip_prefix(buf.buf, "lock ", &name)) {
 416                         if (transport->pack_lockfile)
 417                                 warning(_("%s also locked %s"), data->name, name);
 418                         else
 419                                 transport->pack_lockfile = xstrdup(name);
 420                 }
 421                 else if (data->check_connectivity &&
 422                          data->transport_options.check_self_contained_and_connected &&
 423                          !strcmp(buf.buf, "connectivity-ok"))
 424                         data->transport_options.self_contained_and_connected = 1;
 425                 else if (!buf.len)
 426                         break;
 427                 else
 428                         warning(_("%s unexpectedly said: '%s'"), data->name, buf.buf);
 429         }
 430         strbuf_release(&buf);
 431         return 0;
 432 }
 433
 434 static int get_importer(struct transport *transport, struct child_process *fastimport)
 435 {
 436         struct child_process *helper = get_helper(transport);
 437         struct helper_data *data = transport->data;
 438         int cat_blob_fd, code;
 439         child_process_init(fastimport);
 440         fastimport->in = xdup(helper->out);
 441         argv_array_push(&fastimport->args, "fast-import");
 442         argv_array_push(&fastimport->args, "--allow-unsafe-features");
 443         argv_array_push(&fastimport->args, debug ? "--stats" : "--quiet");
 444
 445         if (data->bidi_import) {
 446                 cat_blob_fd = xdup(helper->in);
 447                 argv_array_pushf(&fastimport->args, "--cat-blob-fd=%d", cat_blob_fd);
 448         }
 449         fastimport->git_cmd = 1;
 450
 451         code = start_command(fastimport);
 452         return code;
 453 }
 454
 455 static int get_exporter(struct transport *transport,
 456                         struct child_process *fastexport,
 457                         struct string_list *revlist_args)
 458 {
 459         struct helper_data *data = transport->data;
 460         struct child_process *helper = get_helper(transport);
 461         int i;
 462
 463         child_process_init(fastexport);
 464
 465         /* we need to duplicate helper->in because we want to use it after
 466          * fastexport is done with it. */
 467         fastexport->out = dup(helper->in);
 468         argv_array_push(&fastexport->args, "fast-export");
 469         argv_array_push(&fastexport->args, "--use-done-feature");
 470         argv_array_push(&fastexport->args, data->signed_tags ?
 471                 "--signed-tags=verbatim" : "--signed-tags=warn-strip");
 472         if (data->export_marks)
 473                 argv_array_pushf(&fastexport->args, "--export-marks=%s.tmp", data->export_marks);
 474         if (data->import_marks)
 475                 argv_array_pushf(&fastexport->args, "--import-marks=%s", data->import_marks);
 476
 477         for (i = 0; i < revlist_args->nr; i++)
 478                 argv_array_push(&fastexport->args, revlist_args->items[i].string);
 479
 480         fastexport->git_cmd = 1;
 481         return start_command(fastexport);
 482 }
 483
 484 static int fetch_with_import(struct transport *transport,
 485                              int nr_heads, struct ref **to_fetch)
 486 {
 487         struct child_process fastimport;
 488         struct helper_data *data = transport->data;
 489         int i;
 490         struct ref *posn;
 491         struct strbuf buf = STRBUF_INIT;
 492
 493         get_helper(transport);
 494
 495         if (get_importer(transport, &fastimport))
 496                 die(_("couldn't run fast-import"));
 497
 498         for (i = 0; i < nr_heads; i++) {
 499                 posn = to_fetch[i];
 500                 if (posn->status & REF_STATUS_UPTODATE)
 501                         continue;
 502
 503                 strbuf_addf(&buf, "import %s\n",
 504                             posn->symref ? posn->symref : posn->name);
 505                 sendline(data, &buf);
 506                 strbuf_reset(&buf);
 507         }
 508
 509         write_constant(data->helper->in, "\n");
 510         /*
 511          * remote-helpers that advertise the bidi-import capability are required to
 512          * buffer the complete batch of import commands until this newline before
 513          * sending data to fast-import.
 514          * These helpers read back data from fast-import on their stdin, which could
 515          * be mixed with import commands, otherwise.
 516          */
 517
 518         if (finish_command(&fastimport))
 519                 die(_("error while running fast-import"));
 520
 521         /*
 522          * The fast-import stream of a remote helper that advertises
 523          * the "refspec" capability writes to the refs named after the
 524          * right hand side of the first refspec matching each ref we
 525          * were fetching.
 526          *
 527          * (If no "refspec" capability was specified, for historical
 528          * reasons we default to the equivalent of *:*.)
 529          *
 530          * Store the result in to_fetch[i].old_sha1.  Callers such
 531          * as "git fetch" can use the value to write feedback to the
 532          * terminal, populate FETCH_HEAD, and determine what new value
 533          * should be written to peer_ref if the update is a
 534          * fast-forward or this is a forced update.
 535          */
 536         for (i = 0; i < nr_heads; i++) {
 537                 char *private, *name;
 538                 posn = to_fetch[i];
 539                 if (posn->status & REF_STATUS_UPTODATE)
 540                         continue;
 541                 name = posn->symref ? posn->symref : posn->name;
 542                 if (data->rs.nr)
 543                         private = apply_refspecs(&data->rs, name);
 544                 else
 545                         private = xstrdup(name);
 546                 if (private) {
 547                         if (read_ref(private, &posn->old_oid) < 0)
 548                                 die(_("could not read ref %s"), private);
 549                         free(private);
 550                 }
 551         }
 552         strbuf_release(&buf);
 553         return 0;
 554 }
 555
 556 static int run_connect(struct transport *transport, struct strbuf *cmdbuf)
 557 {
 558         struct helper_data *data = transport->data;
 559         int ret = 0;
 560         int duped;
 561         FILE *input;
 562         struct child_process *helper;
 563
 564         helper = get_helper(transport);
 565
 566         /*
 567          * Yes, dup the pipe another time, as we need unbuffered version
 568          * of input pipe as FILE*. fclose() closes the underlying fd and
 569          * stream buffering only can be changed before first I/O operation
 570          * on it.
 571          */
 572         duped = dup(helper->out);
 573         if (duped < 0)
 574                 die_errno(_("can't dup helper output fd"));
 575         input = xfdopen(duped, "r");
 576         setvbuf(input, NULL, _IONBF, 0);
 577
 578         sendline(data, cmdbuf);
 579         if (recvline_fh(input, cmdbuf))
 580                 exit(128);
 581
 582         if (!strcmp(cmdbuf->buf, "")) {
 583                 data->no_disconnect_req = 1;
 584                 if (debug)
 585                         fprintf(stderr, "Debug: Smart transport connection "
 586                                 "ready.\n");
 587                 ret = 1;
 588         } else if (!strcmp(cmdbuf->buf, "fallback")) {
 589                 if (debug)
 590                         fprintf(stderr, "Debug: Falling back to dumb "
 591                                 "transport.\n");
 592         } else {
 593                 die(_("unknown response to connect: %s"),
 594                     cmdbuf->buf);
 595         }
 596
 597         fclose(input);
 598         return ret;
 599 }
 600
 601 static int process_connect_service(struct transport *transport,
 602                                    const char *name, const char *exec)
 603 {
 604         struct helper_data *data = transport->data;
 605         struct strbuf cmdbuf = STRBUF_INIT;
 606         int ret = 0;
 607
 608         /*
 609          * Handle --upload-pack and friends. This is fire and forget...
 610          * just warn if it fails.
 611          */
 612         if (strcmp(name, exec)) {
 613                 int r = set_helper_option(transport, "servpath", exec);
 614                 if (r > 0)
 615                         warning(_("setting remote service path not supported by protocol"));
 616                 else if (r < 0)
 617                         warning(_("invalid remote service path"));
 618         }
 619
 620         if (data->connect) {
 621                 strbuf_addf(&cmdbuf, "connect %s\n", name);
 622                 ret = run_connect(transport, &cmdbuf);
 623         } else if (data->stateless_connect &&
 624                    (get_protocol_version_config() == protocol_v2) &&
 625                    !strcmp("git-upload-pack", name)) {
 626                 strbuf_addf(&cmdbuf, "stateless-connect %s\n", name);
 627                 ret = run_connect(transport, &cmdbuf);
 628                 if (ret)
 629                         transport->stateless_rpc = 1;
 630         }
 631
 632         strbuf_release(&cmdbuf);
 633         return ret;
 634 }
 635
 636 static int process_connect(struct transport *transport,
 637                                      int for_push)
 638 {
 639         struct helper_data *data = transport->data;
 640         const char *name;
 641         const char *exec;
 642
 643         name = for_push ? "git-receive-pack" : "git-upload-pack";
 644         if (for_push)
 645                 exec = data->transport_options.receivepack;
 646         else
 647                 exec = data->transport_options.uploadpack;
 648
 649         return process_connect_service(transport, name, exec);
 650 }
 651
 652 static int connect_helper(struct transport *transport, const char *name,
 653                    const char *exec, int fd[2])
 654 {
 655         struct helper_data *data = transport->data;
 656
 657         /* Get_helper so connect is inited. */
 658         get_helper(transport);
 659         if (!data->connect)
 660                 die(_("operation not supported by protocol"));
 661
 662         if (!process_connect_service(transport, name, exec))
 663                 die(_("can't connect to subservice %s"), name);
 664
 665         fd[0] = data->helper->out;
 666         fd[1] = data->helper->in;
 667         return 0;
 668 }
 669
 670 static struct ref *get_refs_list_using_list(struct transport *transport,
 671                                             int for_push);
 672
 673 static int fetch(struct transport *transport,
 674                  int nr_heads, struct ref **to_fetch)
 675 {
 676         struct helper_data *data = transport->data;
 677         int i, count;
 678
 679         get_helper(transport);
 680
 681         if (process_connect(transport, 0)) {
 682                 do_take_over(transport);
 683                 return transport->vtable->fetch(transport, nr_heads, to_fetch);
 684         }
 685
 686         if (!data->get_refs_list_called)
 687                 get_refs_list_using_list(transport, 0);
 688
 689         count = 0;
 690         for (i = 0; i < nr_heads; i++)
 691                 if (!(to_fetch[i]->status & REF_STATUS_UPTODATE))
 692                         count++;
 693
 694         if (!count)
 695                 return 0;
 696
 697         if (data->check_connectivity &&
 698             data->transport_options.check_self_contained_and_connected)
 699                 set_helper_option(transport, "check-connectivity", "true");
 700
 701         if (transport->cloning)
 702                 set_helper_option(transport, "cloning", "true");
 703
 704         if (data->transport_options.update_shallow)
 705                 set_helper_option(transport, "update-shallow", "true");
 706
 707         if (data->transport_options.filter_options.choice) {
 708                 const char *spec = expand_list_objects_filter_spec(
 709                         &data->transport_options.filter_options);
 710                 set_helper_option(transport, "filter", spec);
 711         }
 712
 713         if (data->transport_options.negotiation_tips)
 714                 warning("Ignoring --negotiation-tip because the protocol does not support it.");
 715
 716         if (data->fetch)
 717                 return fetch_with_fetch(transport, nr_heads, to_fetch);
 718
 719         if (data->import)
 720                 return fetch_with_import(transport, nr_heads, to_fetch);
 721
 722         return -1;
 723 }
 724
 725 static int push_update_ref_status(struct strbuf *buf,
 726                                    struct ref **ref,
 727                                    struct ref *remote_refs)
 728 {
 729         char *refname, *msg;
 730         int status, forced = 0;
 731
 732         if (starts_with(buf->buf, "ok ")) {
 733                 status = REF_STATUS_OK;
 734                 refname = buf->buf + 3;
 735         } else if (starts_with(buf->buf, "error ")) {
 736                 status = REF_STATUS_REMOTE_REJECT;
 737                 refname = buf->buf + 6;
 738         } else
 739                 die(_("expected ok/error, helper said '%s'"), buf->buf);
 740
 741         msg = strchr(refname, ' ');
 742         if (msg) {
 743                 struct strbuf msg_buf = STRBUF_INIT;
 744                 const char *end;
 745
 746                 *msg++ = '\0';
 747                 if (!unquote_c_style(&msg_buf, msg, &end))
 748                         msg = strbuf_detach(&msg_buf, NULL);
 749                 else
 750                         msg = xstrdup(msg);
 751                 strbuf_release(&msg_buf);
 752
 753                 if (!strcmp(msg, "no match")) {
 754                         status = REF_STATUS_NONE;
 755                         FREE_AND_NULL(msg);
 756                 }
 757                 else if (!strcmp(msg, "up to date")) {
 758                         status = REF_STATUS_UPTODATE;
 759                         FREE_AND_NULL(msg);
 760                 }
 761                 else if (!strcmp(msg, "non-fast forward")) {
 762                         status = REF_STATUS_REJECT_NONFASTFORWARD;
 763                         FREE_AND_NULL(msg);
 764                 }
 765                 else if (!strcmp(msg, "already exists")) {
 766                         status = REF_STATUS_REJECT_ALREADY_EXISTS;
 767                         FREE_AND_NULL(msg);
 768                 }
 769                 else if (!strcmp(msg, "fetch first")) {
 770                         status = REF_STATUS_REJECT_FETCH_FIRST;
 771                         FREE_AND_NULL(msg);
 772                 }
 773                 else if (!strcmp(msg, "needs force")) {
 774                         status = REF_STATUS_REJECT_NEEDS_FORCE;
 775                         FREE_AND_NULL(msg);
 776                 }
 777                 else if (!strcmp(msg, "stale info")) {
 778                         status = REF_STATUS_REJECT_STALE;
 779                         FREE_AND_NULL(msg);
 780                 }
 781                 else if (!strcmp(msg, "forced update")) {
 782                         forced = 1;
 783                         FREE_AND_NULL(msg);
 784                 }
 785         }
 786
 787         if (*ref)
 788                 *ref = find_ref_by_name(*ref, refname);
 789         if (!*ref)
 790                 *ref = find_ref_by_name(remote_refs, refname);
 791         if (!*ref) {
 792                 warning(_("helper reported unexpected status of %s"), refname);
 793                 return 1;
 794         }
 795
 796         if ((*ref)->status != REF_STATUS_NONE) {
 797                 /*
 798                  * Earlier, the ref was marked not to be pushed, so ignore the ref
 799                  * status reported by the remote helper if the latter is 'no match'.
 800                  */
 801                 if (status == REF_STATUS_NONE)
 802                         return 1;
 803         }
 804
 805         (*ref)->status = status;
 806         (*ref)->forced_update |= forced;
 807         (*ref)->remote_status = msg;
 808         return !(status == REF_STATUS_OK);
 809 }
 810
 811 static int push_update_refs_status(struct helper_data *data,
 812                                     struct ref *remote_refs,
 813                                     int flags)
 814 {
 815         struct strbuf buf = STRBUF_INIT;
 816         struct ref *ref = remote_refs;
 817         int ret = 0;
 818
 819         for (;;) {
 820                 char *private;
 821
 822                 if (recvline(data, &buf)) {
 823                         ret = 1;
 824                         break;
 825                 }
 826
 827                 if (!buf.len)
 828                         break;
 829
 830                 if (push_update_ref_status(&buf, &ref, remote_refs))
 831                         continue;
 832
 833                 if (flags & TRANSPORT_PUSH_DRY_RUN || !data->rs.nr || data->no_private_update)
 834                         continue;
 835
 836                 /* propagate back the update to the remote namespace */
 837                 private = apply_refspecs(&data->rs, ref->name);
 838                 if (!private)
 839                         continue;
 840                 update_ref("update by helper", private, &ref->new_oid, NULL,
 841                            0, 0);
 842                 free(private);
 843         }
 844         strbuf_release(&buf);
 845         return ret;
 846 }
 847
 848 static void set_common_push_options(struct transport *transport,
 849                                    const char *name, int flags)
 850 {
 851         if (flags & TRANSPORT_PUSH_DRY_RUN) {
 852                 if (set_helper_option(transport, "dry-run", "true") != 0)
 853                         die(_("helper %s does not support dry-run"), name);
 854         } else if (flags & TRANSPORT_PUSH_CERT_ALWAYS) {
 855                 if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "true") != 0)
 856                         die(_("helper %s does not support --signed"), name);
 857         } else if (flags & TRANSPORT_PUSH_CERT_IF_ASKED) {
 858                 if (set_helper_option(transport, TRANS_OPT_PUSH_CERT, "if-asked") != 0)
 859                         die(_("helper %s does not support --signed=if-asked"), name);
 860         }
 861
 862         if (flags & TRANSPORT_PUSH_ATOMIC)
 863                 if (set_helper_option(transport, TRANS_OPT_ATOMIC, "true") != 0)
 864                         die(_("helper %s does not support --atomic"), name);
 865
 866         if (flags & TRANSPORT_PUSH_OPTIONS) {
 867                 struct string_list_item *item;
 868                 for_each_string_list_item(item, transport->push_options)
 869                         if (set_helper_option(transport, "push-option", item->string) != 0)
 870                                 die(_("helper %s does not support 'push-option'"), name);
 871         }
 872 }
 873
 874 static int push_refs_with_push(struct transport *transport,
 875                                struct ref *remote_refs, int flags)
 876 {
 877         int force_all = flags & TRANSPORT_PUSH_FORCE;
 878         int mirror = flags & TRANSPORT_PUSH_MIRROR;
 879         int atomic = flags & TRANSPORT_PUSH_ATOMIC;
 880         struct helper_data *data = transport->data;
 881         struct strbuf buf = STRBUF_INIT;
 882         struct ref *ref;
 883         struct string_list cas_options = STRING_LIST_INIT_DUP;
 884         struct string_list_item *cas_option;
 885
 886         get_helper(transport);
 887         if (!data->push)
 888                 return 1;
 889
 890         for (ref = remote_refs; ref; ref = ref->next) {
 891                 if (!ref->peer_ref && !mirror)
 892                         continue;
 893
 894                 /* Check for statuses set by set_ref_status_for_push() */
 895                 switch (ref->status) {
 896                 case REF_STATUS_REJECT_NONFASTFORWARD:
 897                 case REF_STATUS_REJECT_STALE:
 898                 case REF_STATUS_REJECT_ALREADY_EXISTS:
 899                         if (atomic) {
 900                                 reject_atomic_push(remote_refs, mirror);
 901                                 string_list_clear(&cas_options, 0);
 902                                 return 0;
 903                         } else
 904                                 continue;
 905                 case REF_STATUS_UPTODATE:
 906                         continue;
 907                 default:
 908                         ; /* do nothing */
 909                 }
 910
 911                 if (force_all)
 912                         ref->force = 1;
 913
 914                 strbuf_addstr(&buf, "push ");
 915                 if (!ref->deletion) {
 916                         if (ref->force)
 917                                 strbuf_addch(&buf, '+');
 918                         if (ref->peer_ref)
 919                                 strbuf_addstr(&buf, ref->peer_ref->name);
 920                         else
 921                                 strbuf_addstr(&buf, oid_to_hex(&ref->new_oid));
 922                 }
 923                 strbuf_addch(&buf, ':');
 924                 strbuf_addstr(&buf, ref->name);
 925                 strbuf_addch(&buf, '\n');
 926
 927                 /*
 928                  * The "--force-with-lease" options without explicit
 929                  * values to expect have already been expanded into
 930                  * the ref->old_oid_expect[] field; we can ignore
 931                  * transport->smart_options->cas altogether and instead
 932                  * can enumerate them from the refs.
 933                  */
 934                 if (ref->expect_old_sha1) {
 935                         struct strbuf cas = STRBUF_INIT;
 936                         strbuf_addf(&cas, "%s:%s",
 937                                     ref->name, oid_to_hex(&ref->old_oid_expect));
 938                         string_list_append_nodup(&cas_options,
 939                                                  strbuf_detach(&cas, NULL));
 940                 }
 941         }
 942         if (buf.len == 0) {
 943                 string_list_clear(&cas_options, 0);
 944                 return 0;
 945         }
 946
 947         for_each_string_list_item(cas_option, &cas_options)
 948                 set_helper_option(transport, "cas", cas_option->string);
 949         set_common_push_options(transport, data->name, flags);
 950
 951         strbuf_addch(&buf, '\n');
 952         sendline(data, &buf);
 953         strbuf_release(&buf);
 954         string_list_clear(&cas_options, 0);
 955
 956         return push_update_refs_status(data, remote_refs, flags);
 957 }
 958
 959 static int push_refs_with_export(struct transport *transport,
 960                 struct ref *remote_refs, int flags)
 961 {
 962         struct ref *ref;
 963         struct child_process *helper, exporter;
 964         struct helper_data *data = transport->data;
 965         struct string_list revlist_args = STRING_LIST_INIT_DUP;
 966         struct strbuf buf = STRBUF_INIT;
 967
 968         if (!data->rs.nr)
 969                 die(_("remote-helper doesn't support push; refspec needed"));
 970
 971         set_common_push_options(transport, data->name, flags);
 972         if (flags & TRANSPORT_PUSH_FORCE) {
 973                 if (set_helper_option(transport, "force", "true") != 0)
 974                         warning(_("helper %s does not support 'force'"), data->name);
 975         }
 976
 977         helper = get_helper(transport);
 978
 979         write_constant(helper->in, "export\n");
 980
 981         for (ref = remote_refs; ref; ref = ref->next) {
 982                 char *private;
 983                 struct object_id oid;
 984
 985                 private = apply_refspecs(&data->rs, ref->name);
 986                 if (private && !get_oid(private, &oid)) {
 987                         strbuf_addf(&buf, "^%s", private);
 988                         string_list_append_nodup(&revlist_args,
 989                                                  strbuf_detach(&buf, NULL));
 990                         oidcpy(&ref->old_oid, &oid);
 991                 }
 992                 free(private);
 993
 994                 if (ref->peer_ref) {
 995                         if (strcmp(ref->name, ref->peer_ref->name)) {
 996                                 if (!ref->deletion) {
 997                                         const char *name;
 998                                         int flag;
 999
1000                                         /* Follow symbolic refs (mainly for HEAD). */
1001                                         name = resolve_ref_unsafe(ref->peer_ref->name,
1002                                                                   RESOLVE_REF_READING,
1003                                                                   &oid, &flag);
1004                                         if (!name || !(flag & REF_ISSYMREF))
1005                                                 name = ref->peer_ref->name;
1006
1007                                         strbuf_addf(&buf, "%s:%s", name, ref->name);
1008                                 } else
1009                                         strbuf_addf(&buf, ":%s", ref->name);
1010
1011                                 string_list_append(&revlist_args, "--refspec");
1012                                 string_list_append(&revlist_args, buf.buf);
1013                                 strbuf_release(&buf);
1014                         }
1015                         if (!ref->deletion)
1016                                 string_list_append(&revlist_args, ref->peer_ref->name);
1017                 }
1018         }
1019
1020         if (get_exporter(transport, &exporter, &revlist_args))
1021                 die(_("couldn't run fast-export"));
1022
1023         string_list_clear(&revlist_args, 1);
1024
1025         if (finish_command(&exporter))
1026                 die(_("error while running fast-export"));
1027         if (push_update_refs_status(data, remote_refs, flags))
1028                 return 1;
1029
1030         if (data->export_marks) {
1031                 strbuf_addf(&buf, "%s.tmp", data->export_marks);
1032                 rename(buf.buf, data->export_marks);
1033                 strbuf_release(&buf);
1034         }
1035
1036         return 0;
1037 }
1038
1039 static int push_refs(struct transport *transport,
1040                 struct ref *remote_refs, int flags)
1041 {
1042         struct helper_data *data = transport->data;
1043
1044         if (process_connect(transport, 1)) {
1045                 do_take_over(transport);
1046                 return transport->vtable->push_refs(transport, remote_refs, flags);
1047         }
1048
1049         if (!remote_refs) {
1050                 fprintf(stderr,
1051                         _("No refs in common and none specified; doing nothing.\n"
1052                           "Perhaps you should specify a branch such as 'master'.\n"));
1053                 return 0;
1054         }
1055
1056         if (data->push)
1057                 return push_refs_with_push(transport, remote_refs, flags);
1058
1059         if (data->export)
1060                 return push_refs_with_export(transport, remote_refs, flags);
1061
1062         return -1;
1063 }
1064
1065
1066 static int has_attribute(const char *attrs, const char *attr)
1067 {
1068         int len;
1069         if (!attrs)
1070                 return 0;
1071
1072         len = strlen(attr);
1073         for (;;) {
1074                 const char *space = strchrnul(attrs, ' ');
1075                 if (len == space - attrs && !strncmp(attrs, attr, len))
1076                         return 1;
1077                 if (!*space)
1078                         return 0;
1079                 attrs = space + 1;
1080         }
1081 }
1082
1083 static struct ref *get_refs_list(struct transport *transport, int for_push,
1084                                  const struct argv_array *ref_prefixes)
1085 {
1086         get_helper(transport);
1087
1088         if (process_connect(transport, for_push)) {
1089                 do_take_over(transport);
1090                 return transport->vtable->get_refs_list(transport, for_push, ref_prefixes);
1091         }
1092
1093         return get_refs_list_using_list(transport, for_push);
1094 }
1095
1096 static struct ref *get_refs_list_using_list(struct transport *transport,
1097                                             int for_push)
1098 {
1099         struct helper_data *data = transport->data;
1100         struct child_process *helper;
1101         struct ref *ret = NULL;
1102         struct ref **tail = &ret;
1103         struct ref *posn;
1104         struct strbuf buf = STRBUF_INIT;
1105
1106         data->get_refs_list_called = 1;
1107         helper = get_helper(transport);
1108
1109         if (data->object_format) {
1110                 write_str_in_full(helper->in, "option object-format\n");
1111                 if (recvline(data, &buf) || strcmp(buf.buf, "ok"))
1112                         exit(128);
1113         }
1114
1115         if (data->push && for_push)
1116                 write_str_in_full(helper->in, "list for-push\n");
1117         else
1118                 write_str_in_full(helper->in, "list\n");
1119
1120         while (1) {
1121                 char *eov, *eon;
1122                 if (recvline(data, &buf))
1123                         exit(128);
1124
1125                 if (!*buf.buf)
1126                         break;
1127                 else if (buf.buf[0] == ':') {
1128                         const char *value;
1129                         if (skip_prefix(buf.buf, ":object-format ", &value)) {
1130                                 int algo = hash_algo_by_name(value);
1131                                 if (algo == GIT_HASH_UNKNOWN)
1132                                         die(_("unsupported object format '%s'"),
1133                                             value);
1134                                 transport->hash_algo = &hash_algos[algo];
1135                         }
1136                         continue;
1137                 }
1138
1139                 eov = strchr(buf.buf, ' ');
1140                 if (!eov)
1141                         die(_("malformed response in ref list: %s"), buf.buf);
1142                 eon = strchr(eov + 1, ' ');
1143                 *eov = '\0';
1144                 if (eon)
1145                         *eon = '\0';
1146                 *tail = alloc_ref(eov + 1);
1147                 if (buf.buf[0] == '@')
1148                         (*tail)->symref = xstrdup(buf.buf + 1);
1149                 else if (buf.buf[0] != '?')
1150                         get_oid_hex_algop(buf.buf, &(*tail)->old_oid, transport->hash_algo);
1151                 if (eon) {
1152                         if (has_attribute(eon + 1, "unchanged")) {
1153                                 (*tail)->status |= REF_STATUS_UPTODATE;
1154                                 if (read_ref((*tail)->name, &(*tail)->old_oid) < 0)
1155                                         die(_("could not read ref %s"),
1156                                             (*tail)->name);
1157                         }
1158                 }
1159                 tail = &((*tail)->next);
1160         }
1161         if (debug)
1162                 fprintf(stderr, "Debug: Read ref listing.\n");
1163         strbuf_release(&buf);
1164
1165         for (posn = ret; posn; posn = posn->next)
1166                 resolve_remote_symref(posn, ret);
1167
1168         return ret;
1169 }
1170
1171 static struct transport_vtable vtable = {
1172         set_helper_option,
1173         get_refs_list,
1174         fetch,
1175         push_refs,
1176         connect_helper,
1177         release_helper
1178 };
1179
1180 int transport_helper_init(struct transport *transport, const char *name)
1181 {
1182         struct helper_data *data = xcalloc(1, sizeof(*data));
1183         data->name = name;
1184
1185         transport_check_allowed(name);
1186
1187         if (getenv("GIT_TRANSPORT_HELPER_DEBUG"))
1188                 debug = 1;
1189
1190         transport->data = data;
1191         transport->vtable = &vtable;
1192         transport->smart_options = &(data->transport_options);
1193         return 0;
1194 }
1195
1196 /*
1197  * Linux pipes can buffer 65536 bytes at once (and most platforms can
1198  * buffer less), so attempt reads and writes with up to that size.
1199  */
1200 #define BUFFERSIZE 65536
1201 /* This should be enough to hold debugging message. */
1202 #define PBUFFERSIZE 8192
1203
1204 /* Print bidirectional transfer loop debug message. */
1205 __attribute__((format (printf, 1, 2)))
1206 static void transfer_debug(const char *fmt, ...)
1207 {
1208         /*
1209          * NEEDSWORK: This function is sometimes used from multiple threads, and
1210          * we end up using debug_enabled racily. That "should not matter" since
1211          * we always write the same value, but it's still wrong. This function
1212          * is listed in .tsan-suppressions for the time being.
1213          */
1214
1215         va_list args;
1216         char msgbuf[PBUFFERSIZE];
1217         static int debug_enabled = -1;
1218
1219         if (debug_enabled < 0)
1220                 debug_enabled = getenv("GIT_TRANSLOOP_DEBUG") ? 1 : 0;
1221         if (!debug_enabled)
1222                 return;
1223
1224         va_start(args, fmt);
1225         vsnprintf(msgbuf, PBUFFERSIZE, fmt, args);
1226         va_end(args);
1227         fprintf(stderr, "Transfer loop debugging: %s\n", msgbuf);
1228 }
1229
1230 /* Stream state: More data may be coming in this direction. */
1231 #define SSTATE_TRANSFERRING 0
1232 /*
1233  * Stream state: No more data coming in this direction, flushing rest of
1234  * data.
1235  */
1236 #define SSTATE_FLUSHING 1
1237 /* Stream state: Transfer in this direction finished. */
1238 #define SSTATE_FINISHED 2
1239
1240 #define STATE_NEEDS_READING(state) ((state) <= SSTATE_TRANSFERRING)
1241 #define STATE_NEEDS_WRITING(state) ((state) <= SSTATE_FLUSHING)
1242 #define STATE_NEEDS_CLOSING(state) ((state) == SSTATE_FLUSHING)
1243
1244 /* Unidirectional transfer. */
1245 struct unidirectional_transfer {
1246         /* Source */
1247         int src;
1248         /* Destination */
1249         int dest;
1250         /* Is source socket? */
1251         int src_is_sock;
1252         /* Is destination socket? */
1253         int dest_is_sock;
1254         /* Transfer state (TRANSFERRING/FLUSHING/FINISHED) */
1255         int state;
1256         /* Buffer. */
1257         char buf[BUFFERSIZE];
1258         /* Buffer used. */
1259         size_t bufuse;
1260         /* Name of source. */
1261         const char *src_name;
1262         /* Name of destination. */
1263         const char *dest_name;
1264 };
1265
1266 /* Closes the target (for writing) if transfer has finished. */
1267 static void udt_close_if_finished(struct unidirectional_transfer *t)
1268 {
1269         if (STATE_NEEDS_CLOSING(t->state) && !t->bufuse) {
1270                 t->state = SSTATE_FINISHED;
1271                 if (t->dest_is_sock)
1272                         shutdown(t->dest, SHUT_WR);
1273                 else
1274                         close(t->dest);
1275                 transfer_debug("Closed %s.", t->dest_name);
1276         }
1277 }
1278
1279 /*
1280  * Tries to read data from source into buffer. If buffer is full,
1281  * no data is read. Returns 0 on success, -1 on error.
1282  */
1283 static int udt_do_read(struct unidirectional_transfer *t)
1284 {
1285         ssize_t bytes;
1286
1287         if (t->bufuse == BUFFERSIZE)
1288                 return 0;       /* No space for more. */
1289
1290         transfer_debug("%s is readable", t->src_name);
1291         bytes = xread(t->src, t->buf + t->bufuse, BUFFERSIZE - t->bufuse);
1292         if (bytes < 0) {
1293                 error_errno(_("read(%s) failed"), t->src_name);
1294                 return -1;
1295         } else if (bytes == 0) {
1296                 transfer_debug("%s EOF (with %i bytes in buffer)",
1297                         t->src_name, (int)t->bufuse);
1298                 t->state = SSTATE_FLUSHING;
1299         } else if (bytes > 0) {
1300                 t->bufuse += bytes;
1301                 transfer_debug("Read %i bytes from %s (buffer now at %i)",
1302                         (int)bytes, t->src_name, (int)t->bufuse);
1303         }
1304         return 0;
1305 }
1306
1307 /* Tries to write data from buffer into destination. If buffer is empty,
1308  * no data is written. Returns 0 on success, -1 on error.
1309  */
1310 static int udt_do_write(struct unidirectional_transfer *t)
1311 {
1312         ssize_t bytes;
1313
1314         if (t->bufuse == 0)
1315                 return 0;       /* Nothing to write. */
1316
1317         transfer_debug("%s is writable", t->dest_name);
1318         bytes = xwrite(t->dest, t->buf, t->bufuse);
1319         if (bytes < 0) {
1320                 error_errno(_("write(%s) failed"), t->dest_name);
1321                 return -1;
1322         } else if (bytes > 0) {
1323                 t->bufuse -= bytes;
1324                 if (t->bufuse)
1325                         memmove(t->buf, t->buf + bytes, t->bufuse);
1326                 transfer_debug("Wrote %i bytes to %s (buffer now at %i)",
1327                         (int)bytes, t->dest_name, (int)t->bufuse);
1328         }
1329         return 0;
1330 }
1331
1332
1333 /* State of bidirectional transfer loop. */
1334 struct bidirectional_transfer_state {
1335         /* Direction from program to git. */
1336         struct unidirectional_transfer ptg;
1337         /* Direction from git to program. */
1338         struct unidirectional_transfer gtp;
1339 };
1340
1341 static void *udt_copy_task_routine(void *udt)
1342 {
1343         struct unidirectional_transfer *t = (struct unidirectional_transfer *)udt;
1344         while (t->state != SSTATE_FINISHED) {
1345                 if (STATE_NEEDS_READING(t->state))
1346                         if (udt_do_read(t))
1347                                 return NULL;
1348                 if (STATE_NEEDS_WRITING(t->state))
1349                         if (udt_do_write(t))
1350                                 return NULL;
1351                 if (STATE_NEEDS_CLOSING(t->state))
1352                         udt_close_if_finished(t);
1353         }
1354         return udt;     /* Just some non-NULL value. */
1355 }
1356
1357 #ifndef NO_PTHREADS
1358
1359 /*
1360  * Join thread, with appropriate errors on failure. Name is name for the
1361  * thread (for error messages). Returns 0 on success, 1 on failure.
1362  */
1363 static int tloop_join(pthread_t thread, const char *name)
1364 {
1365         int err;
1366         void *tret;
1367         err = pthread_join(thread, &tret);
1368         if (!tret) {
1369                 error(_("%s thread failed"), name);
1370                 return 1;
1371         }
1372         if (err) {
1373                 error(_("%s thread failed to join: %s"), name, strerror(err));
1374                 return 1;
1375         }
1376         return 0;
1377 }
1378
1379 /*
1380  * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1381  * -1 on failure.
1382  */
1383 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1384 {
1385         pthread_t gtp_thread;
1386         pthread_t ptg_thread;
1387         int err;
1388         int ret = 0;
1389         err = pthread_create(&gtp_thread, NULL, udt_copy_task_routine,
1390                 &s->gtp);
1391         if (err)
1392                 die(_("can't start thread for copying data: %s"), strerror(err));
1393         err = pthread_create(&ptg_thread, NULL, udt_copy_task_routine,
1394                 &s->ptg);
1395         if (err)
1396                 die(_("can't start thread for copying data: %s"), strerror(err));
1397
1398         ret |= tloop_join(gtp_thread, "Git to program copy");
1399         ret |= tloop_join(ptg_thread, "Program to git copy");
1400         return ret;
1401 }
1402 #else
1403
1404 /* Close the source and target (for writing) for transfer. */
1405 static void udt_kill_transfer(struct unidirectional_transfer *t)
1406 {
1407         t->state = SSTATE_FINISHED;
1408         /*
1409          * Socket read end left open isn't a disaster if nobody
1410          * attempts to read from it (mingw compat headers do not
1411          * have SHUT_RD)...
1412          *
1413          * We can't fully close the socket since otherwise gtp
1414          * task would first close the socket it sends data to
1415          * while closing the ptg file descriptors.
1416          */
1417         if (!t->src_is_sock)
1418                 close(t->src);
1419         if (t->dest_is_sock)
1420                 shutdown(t->dest, SHUT_WR);
1421         else
1422                 close(t->dest);
1423 }
1424
1425 /*
1426  * Join process, with appropriate errors on failure. Name is name for the
1427  * process (for error messages). Returns 0 on success, 1 on failure.
1428  */
1429 static int tloop_join(pid_t pid, const char *name)
1430 {
1431         int tret;
1432         if (waitpid(pid, &tret, 0) < 0) {
1433                 error_errno(_("%s process failed to wait"), name);
1434                 return 1;
1435         }
1436         if (!WIFEXITED(tret) || WEXITSTATUS(tret)) {
1437                 error(_("%s process failed"), name);
1438                 return 1;
1439         }
1440         return 0;
1441 }
1442
1443 /*
1444  * Spawn the transfer tasks and then wait for them. Returns 0 on success,
1445  * -1 on failure.
1446  */
1447 static int tloop_spawnwait_tasks(struct bidirectional_transfer_state *s)
1448 {
1449         pid_t pid1, pid2;
1450         int ret = 0;
1451
1452         /* Fork thread #1: git to program. */
1453         pid1 = fork();
1454         if (pid1 < 0)
1455                 die_errno(_("can't start thread for copying data"));
1456         else if (pid1 == 0) {
1457                 udt_kill_transfer(&s->ptg);
1458                 exit(udt_copy_task_routine(&s->gtp) ? 0 : 1);
1459         }
1460
1461         /* Fork thread #2: program to git. */
1462         pid2 = fork();
1463         if (pid2 < 0)
1464                 die_errno(_("can't start thread for copying data"));
1465         else if (pid2 == 0) {
1466                 udt_kill_transfer(&s->gtp);
1467                 exit(udt_copy_task_routine(&s->ptg) ? 0 : 1);
1468         }
1469
1470         /*
1471          * Close both streams in parent as to not interfere with
1472          * end of file detection and wait for both tasks to finish.
1473          */
1474         udt_kill_transfer(&s->gtp);
1475         udt_kill_transfer(&s->ptg);
1476         ret |= tloop_join(pid1, "Git to program copy");
1477         ret |= tloop_join(pid2, "Program to git copy");
1478         return ret;
1479 }
1480 #endif
1481
1482 /*
1483  * Copies data from stdin to output and from input to stdout simultaneously.
1484  * Additionally filtering through given filter. If filter is NULL, uses
1485  * identity filter.
1486  */
1487 int bidirectional_transfer_loop(int input, int output)
1488 {
1489         struct bidirectional_transfer_state state;
1490
1491         /* Fill the state fields. */
1492         state.ptg.src = input;
1493         state.ptg.dest = 1;
1494         state.ptg.src_is_sock = (input == output);
1495         state.ptg.dest_is_sock = 0;
1496         state.ptg.state = SSTATE_TRANSFERRING;
1497         state.ptg.bufuse = 0;
1498         state.ptg.src_name = "remote input";
1499         state.ptg.dest_name = "stdout";
1500
1501         state.gtp.src = 0;
1502         state.gtp.dest = output;
1503         state.gtp.src_is_sock = 0;
1504         state.gtp.dest_is_sock = (input == output);
1505         state.gtp.state = SSTATE_TRANSFERRING;
1506         state.gtp.bufuse = 0;
1507         state.gtp.src_name = "stdin";
1508         state.gtp.dest_name = "remote output";
1509
1510         return tloop_spawnwait_tasks(&state);
1511 }
1512
1513 void reject_atomic_push(struct ref *remote_refs, int mirror_mode)
1514 {
1515         struct ref *ref;
1516
1517         /* Mark other refs as failed */
1518         for (ref = remote_refs; ref; ref = ref->next) {
1519                 if (!ref->peer_ref && !mirror_mode)
1520                         continue;
1521
1522                 switch (ref->status) {
1523                 case REF_STATUS_NONE:
1524                 case REF_STATUS_OK:
1525                 case REF_STATUS_EXPECTING_REPORT:
1526                         ref->status = REF_STATUS_ATOMIC_PUSH_FAILED;
1527                         continue;
1528                 default:
1529                         break; /* do nothing */
1530                 }
1531         }
1532         return;
1533 }