transport.c

   1 #include "cache.h"
   2 #include "config.h"
   3 #include "transport.h"
   4 #include "run-command.h"
   5 #include "pkt-line.h"
   6 #include "fetch-pack.h"
   7 #include "remote.h"
   8 #include "connect.h"
   9 #include "send-pack.h"
  10 #include "walker.h"
  11 #include "bundle.h"
  12 #include "dir.h"
  13 #include "refs.h"
  14 #include "refspec.h"
  15 #include "branch.h"
  16 #include "url.h"
  17 #include "submodule.h"
  18 #include "string-list.h"
  19 #include "sha1-array.h"
  20 #include "sigchain.h"
  21 #include "transport-internal.h"
  22 #include "protocol.h"
  23 #include "object-store.h"
  24 #include "color.h"
  25
  26 static int transport_use_color = -1;
  27 static char transport_colors[][COLOR_MAXLEN] = {
  28         GIT_COLOR_RESET,
  29         GIT_COLOR_RED           /* REJECTED */
  30 };
  31
  32 enum color_transport {
  33         TRANSPORT_COLOR_RESET = 0,
  34         TRANSPORT_COLOR_REJECTED = 1
  35 };
  36
  37 static int transport_color_config(void)
  38 {
  39         const char *keys[] = {
  40                 "color.transport.reset",
  41                 "color.transport.rejected"
  42         }, *key = "color.transport";
  43         char *value;
  44         int i;
  45         static int initialized;
  46
  47         if (initialized)
  48                 return 0;
  49         initialized = 1;
  50
  51         if (!git_config_get_string(key, &value))
  52                 transport_use_color = git_config_colorbool(key, value);
  53
  54         if (!want_color_stderr(transport_use_color))
  55                 return 0;
  56
  57         for (i = 0; i < ARRAY_SIZE(keys); i++)
  58                 if (!git_config_get_string(keys[i], &value)) {
  59                         if (!value)
  60                                 return config_error_nonbool(keys[i]);
  61                         if (color_parse(value, transport_colors[i]) < 0)
  62                                 return -1;
  63                 }
  64
  65         return 0;
  66 }
  67
  68 static const char *transport_get_color(enum color_transport ix)
  69 {
  70         if (want_color_stderr(transport_use_color))
  71                 return transport_colors[ix];
  72         return "";
  73 }
  74
  75 static void set_upstreams(struct transport *transport, struct ref *refs,
  76         int pretend)
  77 {
  78         struct ref *ref;
  79         for (ref = refs; ref; ref = ref->next) {
  80                 const char *localname;
  81                 const char *tmp;
  82                 const char *remotename;
  83                 int flag = 0;
  84                 /*
  85                  * Check suitability for tracking. Must be successful /
  86                  * already up-to-date ref create/modify (not delete).
  87                  */
  88                 if (ref->status != REF_STATUS_OK &&
  89                         ref->status != REF_STATUS_UPTODATE)
  90                         continue;
  91                 if (!ref->peer_ref)
  92                         continue;
  93                 if (is_null_oid(&ref->new_oid))
  94                         continue;
  95
  96                 /* Follow symbolic refs (mainly for HEAD). */
  97                 localname = ref->peer_ref->name;
  98                 remotename = ref->name;
  99                 tmp = resolve_ref_unsafe(localname, RESOLVE_REF_READING,
 100                                          NULL, &flag);
 101                 if (tmp && flag & REF_ISSYMREF &&
 102                         starts_with(tmp, "refs/heads/"))
 103                         localname = tmp;
 104
 105                 /* Both source and destination must be local branches. */
 106                 if (!localname || !starts_with(localname, "refs/heads/"))
 107                         continue;
 108                 if (!remotename || !starts_with(remotename, "refs/heads/"))
 109                         continue;
 110
 111                 if (!pretend)
 112                         install_branch_config(BRANCH_CONFIG_VERBOSE,
 113                                 localname + 11, transport->remote->name,
 114                                 remotename);
 115                 else
 116                         printf(_("Would set upstream of '%s' to '%s' of '%s'\n"),
 117                                 localname + 11, remotename + 11,
 118                                 transport->remote->name);
 119         }
 120 }
 121
 122 struct bundle_transport_data {
 123         int fd;
 124         struct bundle_header header;
 125 };
 126
 127 static struct ref *get_refs_from_bundle(struct transport *transport,
 128                                         int for_push,
 129                                         const struct argv_array *ref_prefixes)
 130 {
 131         struct bundle_transport_data *data = transport->data;
 132         struct ref *result = NULL;
 133         int i;
 134
 135         if (for_push)
 136                 return NULL;
 137
 138         if (data->fd > 0)
 139                 close(data->fd);
 140         data->fd = read_bundle_header(transport->url, &data->header);
 141         if (data->fd < 0)
 142                 die(_("could not read bundle '%s'"), transport->url);
 143         for (i = 0; i < data->header.references.nr; i++) {
 144                 struct ref_list_entry *e = data->header.references.list + i;
 145                 struct ref *ref = alloc_ref(e->name);
 146                 oidcpy(&ref->old_oid, &e->oid);
 147                 ref->next = result;
 148                 result = ref;
 149         }
 150         return result;
 151 }
 152
 153 static int fetch_refs_from_bundle(struct transport *transport,
 154                                int nr_heads, struct ref **to_fetch)
 155 {
 156         struct bundle_transport_data *data = transport->data;
 157         return unbundle(&data->header, data->fd,
 158                         transport->progress ? BUNDLE_VERBOSE : 0);
 159 }
 160
 161 static int close_bundle(struct transport *transport)
 162 {
 163         struct bundle_transport_data *data = transport->data;
 164         if (data->fd > 0)
 165                 close(data->fd);
 166         free(data);
 167         return 0;
 168 }
 169
 170 struct git_transport_data {
 171         struct git_transport_options options;
 172         struct child_process *conn;
 173         int fd[2];
 174         unsigned got_remote_heads : 1;
 175         enum protocol_version version;
 176         struct oid_array extra_have;
 177         struct oid_array shallow;
 178 };
 179
 180 static int set_git_option(struct git_transport_options *opts,
 181                           const char *name, const char *value)
 182 {
 183         if (!strcmp(name, TRANS_OPT_UPLOADPACK)) {
 184                 opts->uploadpack = value;
 185                 return 0;
 186         } else if (!strcmp(name, TRANS_OPT_RECEIVEPACK)) {
 187                 opts->receivepack = value;
 188                 return 0;
 189         } else if (!strcmp(name, TRANS_OPT_THIN)) {
 190                 opts->thin = !!value;
 191                 return 0;
 192         } else if (!strcmp(name, TRANS_OPT_FOLLOWTAGS)) {
 193                 opts->followtags = !!value;
 194                 return 0;
 195         } else if (!strcmp(name, TRANS_OPT_KEEP)) {
 196                 opts->keep = !!value;
 197                 return 0;
 198         } else if (!strcmp(name, TRANS_OPT_UPDATE_SHALLOW)) {
 199                 opts->update_shallow = !!value;
 200                 return 0;
 201         } else if (!strcmp(name, TRANS_OPT_DEPTH)) {
 202                 if (!value)
 203                         opts->depth = 0;
 204                 else {
 205                         char *end;
 206                         opts->depth = strtol(value, &end, 0);
 207                         if (*end)
 208                                 die(_("transport: invalid depth option '%s'"), value);
 209                 }
 210                 return 0;
 211         } else if (!strcmp(name, TRANS_OPT_DEEPEN_SINCE)) {
 212                 opts->deepen_since = value;
 213                 return 0;
 214         } else if (!strcmp(name, TRANS_OPT_DEEPEN_NOT)) {
 215                 opts->deepen_not = (const struct string_list *)value;
 216                 return 0;
 217         } else if (!strcmp(name, TRANS_OPT_DEEPEN_RELATIVE)) {
 218                 opts->deepen_relative = !!value;
 219                 return 0;
 220         } else if (!strcmp(name, TRANS_OPT_FROM_PROMISOR)) {
 221                 opts->from_promisor = !!value;
 222                 return 0;
 223         } else if (!strcmp(name, TRANS_OPT_NO_DEPENDENTS)) {
 224                 opts->no_dependents = !!value;
 225                 return 0;
 226         } else if (!strcmp(name, TRANS_OPT_LIST_OBJECTS_FILTER)) {
 227                 parse_list_objects_filter(&opts->filter_options, value);
 228                 return 0;
 229         }
 230         return 1;
 231 }
 232
 233 static int connect_setup(struct transport *transport, int for_push)
 234 {
 235         struct git_transport_data *data = transport->data;
 236         int flags = transport->verbose > 0 ? CONNECT_VERBOSE : 0;
 237
 238         if (data->conn)
 239                 return 0;
 240
 241         switch (transport->family) {
 242         case TRANSPORT_FAMILY_ALL: break;
 243         case TRANSPORT_FAMILY_IPV4: flags |= CONNECT_IPV4; break;
 244         case TRANSPORT_FAMILY_IPV6: flags |= CONNECT_IPV6; break;
 245         }
 246
 247         data->conn = git_connect(data->fd, transport->url,
 248                                  for_push ? data->options.receivepack :
 249                                  data->options.uploadpack,
 250                                  flags);
 251
 252         return 0;
 253 }
 254
 255 /*
 256  * Obtains the protocol version from the transport and writes it to
 257  * transport->data->version, first connecting if not already connected.
 258  *
 259  * If the protocol version is one that allows skipping the listing of remote
 260  * refs, and must_list_refs is 0, the listing of remote refs is skipped and
 261  * this function returns NULL. Otherwise, this function returns the list of
 262  * remote refs.
 263  */
 264 static struct ref *handshake(struct transport *transport, int for_push,
 265                              const struct argv_array *ref_prefixes,
 266                              int must_list_refs)
 267 {
 268         struct git_transport_data *data = transport->data;
 269         struct ref *refs = NULL;
 270         struct packet_reader reader;
 271
 272         connect_setup(transport, for_push);
 273
 274         packet_reader_init(&reader, data->fd[0], NULL, 0,
 275                            PACKET_READ_CHOMP_NEWLINE |
 276                            PACKET_READ_GENTLE_ON_EOF);
 277
 278         data->version = discover_version(&reader);
 279         switch (data->version) {
 280         case protocol_v2:
 281                 if (must_list_refs)
 282                         get_remote_refs(data->fd[1], &reader, &refs, for_push,
 283                                         ref_prefixes,
 284                                         transport->server_options);
 285                 break;
 286         case protocol_v1:
 287         case protocol_v0:
 288                 get_remote_heads(&reader, &refs,
 289                                  for_push ? REF_NORMAL : 0,
 290                                  &data->extra_have,
 291                                  &data->shallow);
 292                 break;
 293         case protocol_unknown_version:
 294                 BUG("unknown protocol version");
 295         }
 296         data->got_remote_heads = 1;
 297
 298         if (reader.line_peeked)
 299                 BUG("buffer must be empty at the end of handshake()");
 300
 301         return refs;
 302 }
 303
 304 static struct ref *get_refs_via_connect(struct transport *transport, int for_push,
 305                                         const struct argv_array *ref_prefixes)
 306 {
 307         return handshake(transport, for_push, ref_prefixes, 1);
 308 }
 309
 310 static int fetch_refs_via_pack(struct transport *transport,
 311                                int nr_heads, struct ref **to_fetch)
 312 {
 313         int ret = 0;
 314         struct git_transport_data *data = transport->data;
 315         struct ref *refs = NULL;
 316         char *dest = xstrdup(transport->url);
 317         struct fetch_pack_args args;
 318         struct ref *refs_tmp = NULL;
 319
 320         memset(&args, 0, sizeof(args));
 321         args.uploadpack = data->options.uploadpack;
 322         args.keep_pack = data->options.keep;
 323         args.lock_pack = 1;
 324         args.use_thin_pack = data->options.thin;
 325         args.include_tag = data->options.followtags;
 326         args.verbose = (transport->verbose > 1);
 327         args.quiet = (transport->verbose < 0);
 328         args.no_progress = !transport->progress;
 329         args.depth = data->options.depth;
 330         args.deepen_since = data->options.deepen_since;
 331         args.deepen_not = data->options.deepen_not;
 332         args.deepen_relative = data->options.deepen_relative;
 333         args.check_self_contained_and_connected =
 334                 data->options.check_self_contained_and_connected;
 335         args.cloning = transport->cloning;
 336         args.update_shallow = data->options.update_shallow;
 337         args.from_promisor = data->options.from_promisor;
 338         args.no_dependents = data->options.no_dependents;
 339         args.filter_options = data->options.filter_options;
 340         args.stateless_rpc = transport->stateless_rpc;
 341         args.server_options = transport->server_options;
 342         args.negotiation_tips = data->options.negotiation_tips;
 343
 344         if (!data->got_remote_heads) {
 345                 int i;
 346                 int must_list_refs = 0;
 347                 for (i = 0; i < nr_heads; i++) {
 348                         if (!to_fetch[i]->exact_oid) {
 349                                 must_list_refs = 1;
 350                                 break;
 351                         }
 352                 }
 353                 refs_tmp = handshake(transport, 0, NULL, must_list_refs);
 354         }
 355
 356         switch (data->version) {
 357         case protocol_v2:
 358                 refs = fetch_pack(&args, data->fd, data->conn,
 359                                   refs_tmp ? refs_tmp : transport->remote_refs,
 360                                   dest, to_fetch, nr_heads, &data->shallow,
 361                                   &transport->pack_lockfile, data->version);
 362                 break;
 363         case protocol_v1:
 364         case protocol_v0:
 365                 refs = fetch_pack(&args, data->fd, data->conn,
 366                                   refs_tmp ? refs_tmp : transport->remote_refs,
 367                                   dest, to_fetch, nr_heads, &data->shallow,
 368                                   &transport->pack_lockfile, data->version);
 369                 break;
 370         case protocol_unknown_version:
 371                 BUG("unknown protocol version");
 372         }
 373
 374         close(data->fd[0]);
 375         close(data->fd[1]);
 376         if (finish_connect(data->conn))
 377                 ret = -1;
 378         data->conn = NULL;
 379         data->got_remote_heads = 0;
 380         data->options.self_contained_and_connected =
 381                 args.self_contained_and_connected;
 382         data->options.connectivity_checked = args.connectivity_checked;
 383
 384         if (refs == NULL)
 385                 ret = -1;
 386         if (report_unmatched_refs(to_fetch, nr_heads))
 387                 ret = -1;
 388
 389         free_refs(refs_tmp);
 390         free_refs(refs);
 391         free(dest);
 392         return ret;
 393 }
 394
 395 static int push_had_errors(struct ref *ref)
 396 {
 397         for (; ref; ref = ref->next) {
 398                 switch (ref->status) {
 399                 case REF_STATUS_NONE:
 400                 case REF_STATUS_UPTODATE:
 401                 case REF_STATUS_OK:
 402                         break;
 403                 default:
 404                         return 1;
 405                 }
 406         }
 407         return 0;
 408 }
 409
 410 int transport_refs_pushed(struct ref *ref)
 411 {
 412         for (; ref; ref = ref->next) {
 413                 switch(ref->status) {
 414                 case REF_STATUS_NONE:
 415                 case REF_STATUS_UPTODATE:
 416                         break;
 417                 default:
 418                         return 1;
 419                 }
 420         }
 421         return 0;
 422 }
 423
 424 void transport_update_tracking_ref(struct remote *remote, struct ref *ref, int verbose)
 425 {
 426         struct refspec_item rs;
 427
 428         if (ref->status != REF_STATUS_OK && ref->status != REF_STATUS_UPTODATE)
 429                 return;
 430
 431         rs.src = ref->name;
 432         rs.dst = NULL;
 433
 434         if (!remote_find_tracking(remote, &rs)) {
 435                 if (verbose)
 436                         fprintf(stderr, "updating local tracking ref '%s'\n", rs.dst);
 437                 if (ref->deletion) {
 438                         delete_ref(NULL, rs.dst, NULL, 0);
 439                 } else
 440                         update_ref("update by push", rs.dst, &ref->new_oid,
 441                                    NULL, 0, 0);
 442                 free(rs.dst);
 443         }
 444 }
 445
 446 static void print_ref_status(char flag, const char *summary,
 447                              struct ref *to, struct ref *from, const char *msg,
 448                              int porcelain, int summary_width)
 449 {
 450         if (porcelain) {
 451                 if (from)
 452                         fprintf(stdout, "%c\t%s:%s\t", flag, from->name, to->name);
 453                 else
 454                         fprintf(stdout, "%c\t:%s\t", flag, to->name);
 455                 if (msg)
 456                         fprintf(stdout, "%s (%s)\n", summary, msg);
 457                 else
 458                         fprintf(stdout, "%s\n", summary);
 459         } else {
 460                 const char *red = "", *reset = "";
 461                 if (push_had_errors(to)) {
 462                         red = transport_get_color(TRANSPORT_COLOR_REJECTED);
 463                         reset = transport_get_color(TRANSPORT_COLOR_RESET);
 464                 }
 465                 fprintf(stderr, " %s%c %-*s%s ", red, flag, summary_width,
 466                         summary, reset);
 467                 if (from)
 468                         fprintf(stderr, "%s -> %s", prettify_refname(from->name), prettify_refname(to->name));
 469                 else
 470                         fputs(prettify_refname(to->name), stderr);
 471                 if (msg) {
 472                         fputs(" (", stderr);
 473                         fputs(msg, stderr);
 474                         fputc(')', stderr);
 475                 }
 476                 fputc('\n', stderr);
 477         }
 478 }
 479
 480 static void print_ok_ref_status(struct ref *ref, int porcelain, int summary_width)
 481 {
 482         if (ref->deletion)
 483                 print_ref_status('-', "[deleted]", ref, NULL, NULL,
 484                                  porcelain, summary_width);
 485         else if (is_null_oid(&ref->old_oid))
 486                 print_ref_status('*',
 487                         (starts_with(ref->name, "refs/tags/") ? "[new tag]" :
 488                         "[new branch]"),
 489                         ref, ref->peer_ref, NULL, porcelain, summary_width);
 490         else {
 491                 struct strbuf quickref = STRBUF_INIT;
 492                 char type;
 493                 const char *msg;
 494
 495                 strbuf_add_unique_abbrev(&quickref, &ref->old_oid,
 496                                          DEFAULT_ABBREV);
 497                 if (ref->forced_update) {
 498                         strbuf_addstr(&quickref, "...");
 499                         type = '+';
 500                         msg = "forced update";
 501                 } else {
 502                         strbuf_addstr(&quickref, "..");
 503                         type = ' ';
 504                         msg = NULL;
 505                 }
 506                 strbuf_add_unique_abbrev(&quickref, &ref->new_oid,
 507                                          DEFAULT_ABBREV);
 508
 509                 print_ref_status(type, quickref.buf, ref, ref->peer_ref, msg,
 510                                  porcelain, summary_width);
 511                 strbuf_release(&quickref);
 512         }
 513 }
 514
 515 static int print_one_push_status(struct ref *ref, const char *dest, int count,
 516                                  int porcelain, int summary_width)
 517 {
 518         if (!count) {
 519                 char *url = transport_anonymize_url(dest);
 520                 fprintf(porcelain ? stdout : stderr, "To %s\n", url);
 521                 free(url);
 522         }
 523
 524         switch(ref->status) {
 525         case REF_STATUS_NONE:
 526                 print_ref_status('X', "[no match]", ref, NULL, NULL,
 527                                  porcelain, summary_width);
 528                 break;
 529         case REF_STATUS_REJECT_NODELETE:
 530                 print_ref_status('!', "[rejected]", ref, NULL,
 531                                  "remote does not support deleting refs",
 532                                  porcelain, summary_width);
 533                 break;
 534         case REF_STATUS_UPTODATE:
 535                 print_ref_status('=', "[up to date]", ref,
 536                                  ref->peer_ref, NULL, porcelain, summary_width);
 537                 break;
 538         case REF_STATUS_REJECT_NONFASTFORWARD:
 539                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
 540                                  "non-fast-forward", porcelain, summary_width);
 541                 break;
 542         case REF_STATUS_REJECT_ALREADY_EXISTS:
 543                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
 544                                  "already exists", porcelain, summary_width);
 545                 break;
 546         case REF_STATUS_REJECT_FETCH_FIRST:
 547                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
 548                                  "fetch first", porcelain, summary_width);
 549                 break;
 550         case REF_STATUS_REJECT_NEEDS_FORCE:
 551                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
 552                                  "needs force", porcelain, summary_width);
 553                 break;
 554         case REF_STATUS_REJECT_STALE:
 555                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
 556                                  "stale info", porcelain, summary_width);
 557                 break;
 558         case REF_STATUS_REJECT_SHALLOW:
 559                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
 560                                  "new shallow roots not allowed",
 561                                  porcelain, summary_width);
 562                 break;
 563         case REF_STATUS_REMOTE_REJECT:
 564                 print_ref_status('!', "[remote rejected]", ref,
 565                                  ref->deletion ? NULL : ref->peer_ref,
 566                                  ref->remote_status, porcelain, summary_width);
 567                 break;
 568         case REF_STATUS_EXPECTING_REPORT:
 569                 print_ref_status('!', "[remote failure]", ref,
 570                                  ref->deletion ? NULL : ref->peer_ref,
 571                                  "remote failed to report status",
 572                                  porcelain, summary_width);
 573                 break;
 574         case REF_STATUS_ATOMIC_PUSH_FAILED:
 575                 print_ref_status('!', "[rejected]", ref, ref->peer_ref,
 576                                  "atomic push failed", porcelain, summary_width);
 577                 break;
 578         case REF_STATUS_OK:
 579                 print_ok_ref_status(ref, porcelain, summary_width);
 580                 break;
 581         }
 582
 583         return 1;
 584 }
 585
 586 static int measure_abbrev(const struct object_id *oid, int sofar)
 587 {
 588         char hex[GIT_MAX_HEXSZ + 1];
 589         int w = find_unique_abbrev_r(hex, oid, DEFAULT_ABBREV);
 590
 591         return (w < sofar) ? sofar : w;
 592 }
 593
 594 int transport_summary_width(const struct ref *refs)
 595 {
 596         int maxw = -1;
 597
 598         for (; refs; refs = refs->next) {
 599                 maxw = measure_abbrev(&refs->old_oid, maxw);
 600                 maxw = measure_abbrev(&refs->new_oid, maxw);
 601         }
 602         if (maxw < 0)
 603                 maxw = FALLBACK_DEFAULT_ABBREV;
 604         return (2 * maxw + 3);
 605 }
 606
 607 void transport_print_push_status(const char *dest, struct ref *refs,
 608                                   int verbose, int porcelain, unsigned int *reject_reasons)
 609 {
 610         struct ref *ref;
 611         int n = 0;
 612         char *head;
 613         int summary_width = transport_summary_width(refs);
 614
 615         if (transport_color_config() < 0)
 616                 warning(_("could not parse transport.color.* config"));
 617
 618         head = resolve_refdup("HEAD", RESOLVE_REF_READING, NULL, NULL);
 619
 620         if (verbose) {
 621                 for (ref = refs; ref; ref = ref->next)
 622                         if (ref->status == REF_STATUS_UPTODATE)
 623                                 n += print_one_push_status(ref, dest, n,
 624                                                            porcelain, summary_width);
 625         }
 626
 627         for (ref = refs; ref; ref = ref->next)
 628                 if (ref->status == REF_STATUS_OK)
 629                         n += print_one_push_status(ref, dest, n,
 630                                                    porcelain, summary_width);
 631
 632         *reject_reasons = 0;
 633         for (ref = refs; ref; ref = ref->next) {
 634                 if (ref->status != REF_STATUS_NONE &&
 635                     ref->status != REF_STATUS_UPTODATE &&
 636                     ref->status != REF_STATUS_OK)
 637                         n += print_one_push_status(ref, dest, n,
 638                                                    porcelain, summary_width);
 639                 if (ref->status == REF_STATUS_REJECT_NONFASTFORWARD) {
 640                         if (head != NULL && !strcmp(head, ref->name))
 641                                 *reject_reasons |= REJECT_NON_FF_HEAD;
 642                         else
 643                                 *reject_reasons |= REJECT_NON_FF_OTHER;
 644                 } else if (ref->status == REF_STATUS_REJECT_ALREADY_EXISTS) {
 645                         *reject_reasons |= REJECT_ALREADY_EXISTS;
 646                 } else if (ref->status == REF_STATUS_REJECT_FETCH_FIRST) {
 647                         *reject_reasons |= REJECT_FETCH_FIRST;
 648                 } else if (ref->status == REF_STATUS_REJECT_NEEDS_FORCE) {
 649                         *reject_reasons |= REJECT_NEEDS_FORCE;
 650                 }
 651         }
 652         free(head);
 653 }
 654
 655 static int git_transport_push(struct transport *transport, struct ref *remote_refs, int flags)
 656 {
 657         struct git_transport_data *data = transport->data;
 658         struct send_pack_args args;
 659         int ret = 0;
 660
 661         if (transport_color_config() < 0)
 662                 return -1;
 663
 664         if (!data->got_remote_heads)
 665                 get_refs_via_connect(transport, 1, NULL);
 666
 667         memset(&args, 0, sizeof(args));
 668         args.send_mirror = !!(flags & TRANSPORT_PUSH_MIRROR);
 669         args.force_update = !!(flags & TRANSPORT_PUSH_FORCE);
 670         args.use_thin_pack = data->options.thin;
 671         args.verbose = (transport->verbose > 0);
 672         args.quiet = (transport->verbose < 0);
 673         args.progress = transport->progress;
 674         args.dry_run = !!(flags & TRANSPORT_PUSH_DRY_RUN);
 675         args.porcelain = !!(flags & TRANSPORT_PUSH_PORCELAIN);
 676         args.atomic = !!(flags & TRANSPORT_PUSH_ATOMIC);
 677         args.push_options = transport->push_options;
 678         args.url = transport->url;
 679
 680         if (flags & TRANSPORT_PUSH_CERT_ALWAYS)
 681                 args.push_cert = SEND_PACK_PUSH_CERT_ALWAYS;
 682         else if (flags & TRANSPORT_PUSH_CERT_IF_ASKED)
 683                 args.push_cert = SEND_PACK_PUSH_CERT_IF_ASKED;
 684         else
 685                 args.push_cert = SEND_PACK_PUSH_CERT_NEVER;
 686
 687         switch (data->version) {
 688         case protocol_v2:
 689                 die(_("support for protocol v2 not implemented yet"));
 690                 break;
 691         case protocol_v1:
 692         case protocol_v0:
 693                 ret = send_pack(&args, data->fd, data->conn, remote_refs,
 694                                 &data->extra_have);
 695                 break;
 696         case protocol_unknown_version:
 697                 BUG("unknown protocol version");
 698         }
 699
 700         close(data->fd[1]);
 701         close(data->fd[0]);
 702         ret |= finish_connect(data->conn);
 703         data->conn = NULL;
 704         data->got_remote_heads = 0;
 705
 706         return ret;
 707 }
 708
 709 static int connect_git(struct transport *transport, const char *name,
 710                        const char *executable, int fd[2])
 711 {
 712         struct git_transport_data *data = transport->data;
 713         data->conn = git_connect(data->fd, transport->url,
 714                                  executable, 0);
 715         fd[0] = data->fd[0];
 716         fd[1] = data->fd[1];
 717         return 0;
 718 }
 719
 720 static int disconnect_git(struct transport *transport)
 721 {
 722         struct git_transport_data *data = transport->data;
 723         if (data->conn) {
 724                 if (data->got_remote_heads)
 725                         packet_flush(data->fd[1]);
 726                 close(data->fd[0]);
 727                 close(data->fd[1]);
 728                 finish_connect(data->conn);
 729         }
 730
 731         free(data);
 732         return 0;
 733 }
 734
 735 static struct transport_vtable taken_over_vtable = {
 736         NULL,
 737         get_refs_via_connect,
 738         fetch_refs_via_pack,
 739         git_transport_push,
 740         NULL,
 741         disconnect_git
 742 };
 743
 744 void transport_take_over(struct transport *transport,
 745                          struct child_process *child)
 746 {
 747         struct git_transport_data *data;
 748
 749         if (!transport->smart_options)
 750                 BUG("taking over transport requires non-NULL "
 751                     "smart_options field.");
 752
 753         data = xcalloc(1, sizeof(*data));
 754         data->options = *transport->smart_options;
 755         data->conn = child;
 756         data->fd[0] = data->conn->out;
 757         data->fd[1] = data->conn->in;
 758         data->got_remote_heads = 0;
 759         transport->data = data;
 760
 761         transport->vtable = &taken_over_vtable;
 762         transport->smart_options = &(data->options);
 763
 764         transport->cannot_reuse = 1;
 765 }
 766
 767 static int is_file(const char *url)
 768 {
 769         struct stat buf;
 770         if (stat(url, &buf))
 771                 return 0;
 772         return S_ISREG(buf.st_mode);
 773 }
 774
 775 static int external_specification_len(const char *url)
 776 {
 777         return strchr(url, ':') - url;
 778 }
 779
 780 static const struct string_list *protocol_whitelist(void)
 781 {
 782         static int enabled = -1;
 783         static struct string_list allowed = STRING_LIST_INIT_DUP;
 784
 785         if (enabled < 0) {
 786                 const char *v = getenv("GIT_ALLOW_PROTOCOL");
 787                 if (v) {
 788                         string_list_split(&allowed, v, ':', -1);
 789                         string_list_sort(&allowed);
 790                         enabled = 1;
 791                 } else {
 792                         enabled = 0;
 793                 }
 794         }
 795
 796         return enabled ? &allowed : NULL;
 797 }
 798
 799 enum protocol_allow_config {
 800         PROTOCOL_ALLOW_NEVER = 0,
 801         PROTOCOL_ALLOW_USER_ONLY,
 802         PROTOCOL_ALLOW_ALWAYS
 803 };
 804
 805 static enum protocol_allow_config parse_protocol_config(const char *key,
 806                                                         const char *value)
 807 {
 808         if (!strcasecmp(value, "always"))
 809                 return PROTOCOL_ALLOW_ALWAYS;
 810         else if (!strcasecmp(value, "never"))
 811                 return PROTOCOL_ALLOW_NEVER;
 812         else if (!strcasecmp(value, "user"))
 813                 return PROTOCOL_ALLOW_USER_ONLY;
 814
 815         die(_("unknown value for config '%s': %s"), key, value);
 816 }
 817
 818 static enum protocol_allow_config get_protocol_config(const char *type)
 819 {
 820         char *key = xstrfmt("protocol.%s.allow", type);
 821         char *value;
 822
 823         /* first check the per-protocol config */
 824         if (!git_config_get_string(key, &value)) {
 825                 enum protocol_allow_config ret =
 826                         parse_protocol_config(key, value);
 827                 free(key);
 828                 free(value);
 829                 return ret;
 830         }
 831         free(key);
 832
 833         /* if defined, fallback to user-defined default for unknown protocols */
 834         if (!git_config_get_string("protocol.allow", &value)) {
 835                 enum protocol_allow_config ret =
 836                         parse_protocol_config("protocol.allow", value);
 837                 free(value);
 838                 return ret;
 839         }
 840
 841         /* fallback to built-in defaults */
 842         /* known safe */
 843         if (!strcmp(type, "http") ||
 844             !strcmp(type, "https") ||
 845             !strcmp(type, "git") ||
 846             !strcmp(type, "ssh") ||
 847             !strcmp(type, "file"))
 848                 return PROTOCOL_ALLOW_ALWAYS;
 849
 850         /* known scary; err on the side of caution */
 851         if (!strcmp(type, "ext"))
 852                 return PROTOCOL_ALLOW_NEVER;
 853
 854         /* unknown; by default let them be used only directly by the user */
 855         return PROTOCOL_ALLOW_USER_ONLY;
 856 }
 857
 858 int is_transport_allowed(const char *type, int from_user)
 859 {
 860         const struct string_list *whitelist = protocol_whitelist();
 861         if (whitelist)
 862                 return string_list_has_string(whitelist, type);
 863
 864         switch (get_protocol_config(type)) {
 865         case PROTOCOL_ALLOW_ALWAYS:
 866                 return 1;
 867         case PROTOCOL_ALLOW_NEVER:
 868                 return 0;
 869         case PROTOCOL_ALLOW_USER_ONLY:
 870                 if (from_user < 0)
 871                         from_user = git_env_bool("GIT_PROTOCOL_FROM_USER", 1);
 872                 return from_user;
 873         }
 874
 875         BUG("invalid protocol_allow_config type");
 876 }
 877
 878 void transport_check_allowed(const char *type)
 879 {
 880         if (!is_transport_allowed(type, -1))
 881                 die(_("transport '%s' not allowed"), type);
 882 }
 883
 884 static struct transport_vtable bundle_vtable = {
 885         NULL,
 886         get_refs_from_bundle,
 887         fetch_refs_from_bundle,
 888         NULL,
 889         NULL,
 890         close_bundle
 891 };
 892
 893 static struct transport_vtable builtin_smart_vtable = {
 894         NULL,
 895         get_refs_via_connect,
 896         fetch_refs_via_pack,
 897         git_transport_push,
 898         connect_git,
 899         disconnect_git
 900 };
 901
 902 struct transport *transport_get(struct remote *remote, const char *url)
 903 {
 904         const char *helper;
 905         struct transport *ret = xcalloc(1, sizeof(*ret));
 906
 907         ret->progress = isatty(2);
 908
 909         if (!remote)
 910                 BUG("No remote provided to transport_get()");
 911
 912         ret->got_remote_refs = 0;
 913         ret->remote = remote;
 914         helper = remote->foreign_vcs;
 915
 916         if (!url && remote->url)
 917                 url = remote->url[0];
 918         ret->url = url;
 919
 920         /* maybe it is a foreign URL? */
 921         if (url) {
 922                 const char *p = url;
 923
 924                 while (is_urlschemechar(p == url, *p))
 925                         p++;
 926                 if (starts_with(p, "::"))
 927                         helper = xstrndup(url, p - url);
 928         }
 929
 930         if (helper) {
 931                 transport_helper_init(ret, helper);
 932         } else if (starts_with(url, "rsync:")) {
 933                 die(_("git-over-rsync is no longer supported"));
 934         } else if (url_is_local_not_ssh(url) && is_file(url) && is_bundle(url, 1)) {
 935                 struct bundle_transport_data *data = xcalloc(1, sizeof(*data));
 936                 transport_check_allowed("file");
 937                 ret->data = data;
 938                 ret->vtable = &bundle_vtable;
 939                 ret->smart_options = NULL;
 940         } else if (!is_url(url)
 941                 || starts_with(url, "file://")
 942                 || starts_with(url, "git://")
 943                 || starts_with(url, "ssh://")
 944                 || starts_with(url, "git+ssh://") /* deprecated - do not use */
 945                 || starts_with(url, "ssh+git://") /* deprecated - do not use */
 946                 ) {
 947                 /*
 948                  * These are builtin smart transports; "allowed" transports
 949                  * will be checked individually in git_connect.
 950                  */
 951                 struct git_transport_data *data = xcalloc(1, sizeof(*data));
 952                 ret->data = data;
 953                 ret->vtable = &builtin_smart_vtable;
 954                 ret->smart_options = &(data->options);
 955
 956                 data->conn = NULL;
 957                 data->got_remote_heads = 0;
 958         } else {
 959                 /* Unknown protocol in URL. Pass to external handler. */
 960                 int len = external_specification_len(url);
 961                 char *handler = xmemdupz(url, len);
 962                 transport_helper_init(ret, handler);
 963         }
 964
 965         if (ret->smart_options) {
 966                 ret->smart_options->thin = 1;
 967                 ret->smart_options->uploadpack = "git-upload-pack";
 968                 if (remote->uploadpack)
 969                         ret->smart_options->uploadpack = remote->uploadpack;
 970                 ret->smart_options->receivepack = "git-receive-pack";
 971                 if (remote->receivepack)
 972                         ret->smart_options->receivepack = remote->receivepack;
 973         }
 974
 975         return ret;
 976 }
 977
 978 int transport_set_option(struct transport *transport,
 979                          const char *name, const char *value)
 980 {
 981         int git_reports = 1, protocol_reports = 1;
 982
 983         if (transport->smart_options)
 984                 git_reports = set_git_option(transport->smart_options,
 985                                              name, value);
 986
 987         if (transport->vtable->set_option)
 988                 protocol_reports = transport->vtable->set_option(transport,
 989                                                                  name, value);
 990
 991         /* If either report is 0, report 0 (success). */
 992         if (!git_reports || !protocol_reports)
 993                 return 0;
 994         /* If either reports -1 (invalid value), report -1. */
 995         if ((git_reports == -1) || (protocol_reports == -1))
 996                 return -1;
 997         /* Otherwise if both report unknown, report unknown. */
 998         return 1;
 999 }
1000
1001 void transport_set_verbosity(struct transport *transport, int verbosity,
1002         int force_progress)
1003 {
1004         if (verbosity >= 1)
1005                 transport->verbose = verbosity <= 3 ? verbosity : 3;
1006         if (verbosity < 0)
1007                 transport->verbose = -1;
1008
1009         /**
1010          * Rules used to determine whether to report progress (processing aborts
1011          * when a rule is satisfied):
1012          *
1013          *   . Report progress, if force_progress is 1 (ie. --progress).
1014          *   . Don't report progress, if force_progress is 0 (ie. --no-progress).
1015          *   . Don't report progress, if verbosity < 0 (ie. -q/--quiet ).
1016          *   . Report progress if isatty(2) is 1.
1017          **/
1018         if (force_progress >= 0)
1019                 transport->progress = !!force_progress;
1020         else
1021                 transport->progress = verbosity >= 0 && isatty(2);
1022 }
1023
1024 static void die_with_unpushed_submodules(struct string_list *needs_pushing)
1025 {
1026         int i;
1027
1028         fprintf(stderr, _("The following submodule paths contain changes that can\n"
1029                         "not be found on any remote:\n"));
1030         for (i = 0; i < needs_pushing->nr; i++)
1031                 fprintf(stderr, "  %s\n", needs_pushing->items[i].string);
1032         fprintf(stderr, _("\nPlease try\n\n"
1033                           "     git push --recurse-submodules=on-demand\n\n"
1034                           "or cd to the path and use\n\n"
1035                           "     git push\n\n"
1036                           "to push them to a remote.\n\n"));
1037
1038         string_list_clear(needs_pushing, 0);
1039
1040         die(_("Aborting."));
1041 }
1042
1043 static int run_pre_push_hook(struct transport *transport,
1044                              struct ref *remote_refs)
1045 {
1046         int ret = 0, x;
1047         struct ref *r;
1048         struct child_process proc = CHILD_PROCESS_INIT;
1049         struct strbuf buf;
1050         const char *argv[4];
1051
1052         if (!(argv[0] = find_hook("pre-push")))
1053                 return 0;
1054
1055         argv[1] = transport->remote->name;
1056         argv[2] = transport->url;
1057         argv[3] = NULL;
1058
1059         proc.argv = argv;
1060         proc.in = -1;
1061
1062         if (start_command(&proc)) {
1063                 finish_command(&proc);
1064                 return -1;
1065         }
1066
1067         sigchain_push(SIGPIPE, SIG_IGN);
1068
1069         strbuf_init(&buf, 256);
1070
1071         for (r = remote_refs; r; r = r->next) {
1072                 if (!r->peer_ref) continue;
1073                 if (r->status == REF_STATUS_REJECT_NONFASTFORWARD) continue;
1074                 if (r->status == REF_STATUS_REJECT_STALE) continue;
1075                 if (r->status == REF_STATUS_UPTODATE) continue;
1076
1077                 strbuf_reset(&buf);
1078                 strbuf_addf( &buf, "%s %s %s %s\n",
1079                          r->peer_ref->name, oid_to_hex(&r->new_oid),
1080                          r->name, oid_to_hex(&r->old_oid));
1081
1082                 if (write_in_full(proc.in, buf.buf, buf.len) < 0) {
1083                         /* We do not mind if a hook does not read all refs. */
1084                         if (errno != EPIPE)
1085                                 ret = -1;
1086                         break;
1087                 }
1088         }
1089
1090         strbuf_release(&buf);
1091
1092         x = close(proc.in);
1093         if (!ret)
1094                 ret = x;
1095
1096         sigchain_pop(SIGPIPE);
1097
1098         x = finish_command(&proc);
1099         if (!ret)
1100                 ret = x;
1101
1102         return ret;
1103 }
1104
1105 int transport_push(struct transport *transport,
1106                    struct refspec *rs, int flags,
1107                    unsigned int *reject_reasons)
1108 {
1109         *reject_reasons = 0;
1110
1111         if (transport_color_config() < 0)
1112                 return -1;
1113
1114         if (transport->vtable->push_refs) {
1115                 struct ref *remote_refs;
1116                 struct ref *local_refs = get_local_heads();
1117                 int match_flags = MATCH_REFS_NONE;
1118                 int verbose = (transport->verbose > 0);
1119                 int quiet = (transport->verbose < 0);
1120                 int porcelain = flags & TRANSPORT_PUSH_PORCELAIN;
1121                 int pretend = flags & TRANSPORT_PUSH_DRY_RUN;
1122                 int push_ret, ret, err;
1123                 struct argv_array ref_prefixes = ARGV_ARRAY_INIT;
1124
1125                 if (check_push_refs(local_refs, rs) < 0)
1126                         return -1;
1127
1128                 refspec_ref_prefixes(rs, &ref_prefixes);
1129
1130                 remote_refs = transport->vtable->get_refs_list(transport, 1,
1131                                                                &ref_prefixes);
1132
1133                 argv_array_clear(&ref_prefixes);
1134
1135                 if (flags & TRANSPORT_PUSH_ALL)
1136                         match_flags |= MATCH_REFS_ALL;
1137                 if (flags & TRANSPORT_PUSH_MIRROR)
1138                         match_flags |= MATCH_REFS_MIRROR;
1139                 if (flags & TRANSPORT_PUSH_PRUNE)
1140                         match_flags |= MATCH_REFS_PRUNE;
1141                 if (flags & TRANSPORT_PUSH_FOLLOW_TAGS)
1142                         match_flags |= MATCH_REFS_FOLLOW_TAGS;
1143
1144                 if (match_push_refs(local_refs, &remote_refs, rs, match_flags))
1145                         return -1;
1146
1147                 if (transport->smart_options &&
1148                     transport->smart_options->cas &&
1149                     !is_empty_cas(transport->smart_options->cas))
1150                         apply_push_cas(transport->smart_options->cas,
1151                                        transport->remote, remote_refs);
1152
1153                 set_ref_status_for_push(remote_refs,
1154                         flags & TRANSPORT_PUSH_MIRROR,
1155                         flags & TRANSPORT_PUSH_FORCE);
1156
1157                 if (!(flags & TRANSPORT_PUSH_NO_HOOK))
1158                         if (run_pre_push_hook(transport, remote_refs))
1159                                 return -1;
1160
1161                 if ((flags & (TRANSPORT_RECURSE_SUBMODULES_ON_DEMAND |
1162                               TRANSPORT_RECURSE_SUBMODULES_ONLY)) &&
1163                     !is_bare_repository()) {
1164                         struct ref *ref = remote_refs;
1165                         struct oid_array commits = OID_ARRAY_INIT;
1166
1167                         for (; ref; ref = ref->next)
1168                                 if (!is_null_oid(&ref->new_oid))
1169                                         oid_array_append(&commits,
1170                                                           &ref->new_oid);
1171
1172                         if (!push_unpushed_submodules(&commits,
1173                                                       transport->remote,
1174                                                       rs,
1175                                                       transport->push_options,
1176                                                       pretend)) {
1177                                 oid_array_clear(&commits);
1178                                 die(_("failed to push all needed submodules"));
1179                         }
1180                         oid_array_clear(&commits);
1181                 }
1182
1183                 if (((flags & TRANSPORT_RECURSE_SUBMODULES_CHECK) ||
1184                      ((flags & (TRANSPORT_RECURSE_SUBMODULES_ON_DEMAND |
1185                                 TRANSPORT_RECURSE_SUBMODULES_ONLY)) &&
1186                       !pretend)) && !is_bare_repository()) {
1187                         struct ref *ref = remote_refs;
1188                         struct string_list needs_pushing = STRING_LIST_INIT_DUP;
1189                         struct oid_array commits = OID_ARRAY_INIT;
1190
1191                         for (; ref; ref = ref->next)
1192                                 if (!is_null_oid(&ref->new_oid))
1193                                         oid_array_append(&commits,
1194                                                           &ref->new_oid);
1195
1196                         if (find_unpushed_submodules(&commits, transport->remote->name,
1197                                                 &needs_pushing)) {
1198                                 oid_array_clear(&commits);
1199                                 die_with_unpushed_submodules(&needs_pushing);
1200                         }
1201                         string_list_clear(&needs_pushing, 0);
1202                         oid_array_clear(&commits);
1203                 }
1204
1205                 if (!(flags & TRANSPORT_RECURSE_SUBMODULES_ONLY))
1206                         push_ret = transport->vtable->push_refs(transport, remote_refs, flags);
1207                 else
1208                         push_ret = 0;
1209                 err = push_had_errors(remote_refs);
1210                 ret = push_ret | err;
1211
1212                 if (!quiet || err)
1213                         transport_print_push_status(transport->url, remote_refs,
1214                                         verbose | porcelain, porcelain,
1215                                         reject_reasons);
1216
1217                 if (flags & TRANSPORT_PUSH_SET_UPSTREAM)
1218                         set_upstreams(transport, remote_refs, pretend);
1219
1220                 if (!(flags & (TRANSPORT_PUSH_DRY_RUN |
1221                                TRANSPORT_RECURSE_SUBMODULES_ONLY))) {
1222                         struct ref *ref;
1223                         for (ref = remote_refs; ref; ref = ref->next)
1224                                 transport_update_tracking_ref(transport->remote, ref, verbose);
1225                 }
1226
1227                 if (porcelain && !push_ret)
1228                         puts("Done");
1229                 else if (!quiet && !ret && !transport_refs_pushed(remote_refs))
1230                         fprintf(stderr, "Everything up-to-date\n");
1231
1232                 return ret;
1233         }
1234         return 1;
1235 }
1236
1237 const struct ref *transport_get_remote_refs(struct transport *transport,
1238                                             const struct argv_array *ref_prefixes)
1239 {
1240         if (!transport->got_remote_refs) {
1241                 transport->remote_refs =
1242                         transport->vtable->get_refs_list(transport, 0,
1243                                                          ref_prefixes);
1244                 transport->got_remote_refs = 1;
1245         }
1246
1247         return transport->remote_refs;
1248 }
1249
1250 int transport_fetch_refs(struct transport *transport, struct ref *refs)
1251 {
1252         int rc;
1253         int nr_heads = 0, nr_alloc = 0, nr_refs = 0;
1254         struct ref **heads = NULL;
1255         struct ref *rm;
1256
1257         for (rm = refs; rm; rm = rm->next) {
1258                 nr_refs++;
1259                 if (rm->peer_ref &&
1260                     !is_null_oid(&rm->old_oid) &&
1261                     oideq(&rm->peer_ref->old_oid, &rm->old_oid))
1262                         continue;
1263                 ALLOC_GROW(heads, nr_heads + 1, nr_alloc);
1264                 heads[nr_heads++] = rm;
1265         }
1266
1267         if (!nr_heads) {
1268                 /*
1269                  * When deepening of a shallow repository is requested,
1270                  * then local and remote refs are likely to still be equal.
1271                  * Just feed them all to the fetch method in that case.
1272                  * This condition shouldn't be met in a non-deepening fetch
1273                  * (see builtin/fetch.c:quickfetch()).
1274                  */
1275                 ALLOC_ARRAY(heads, nr_refs);
1276                 for (rm = refs; rm; rm = rm->next)
1277                         heads[nr_heads++] = rm;
1278         }
1279
1280         rc = transport->vtable->fetch(transport, nr_heads, heads);
1281
1282         free(heads);
1283         return rc;
1284 }
1285
1286 void transport_unlock_pack(struct transport *transport)
1287 {
1288         if (transport->pack_lockfile) {
1289                 unlink_or_warn(transport->pack_lockfile);
1290                 FREE_AND_NULL(transport->pack_lockfile);
1291         }
1292 }
1293
1294 int transport_connect(struct transport *transport, const char *name,
1295                       const char *exec, int fd[2])
1296 {
1297         if (transport->vtable->connect)
1298                 return transport->vtable->connect(transport, name, exec, fd);
1299         else
1300                 die(_("operation not supported by protocol"));
1301 }
1302
1303 int transport_disconnect(struct transport *transport)
1304 {
1305         int ret = 0;
1306         if (transport->vtable->disconnect)
1307                 ret = transport->vtable->disconnect(transport);
1308         free(transport);
1309         return ret;
1310 }
1311
1312 /*
1313  * Strip username (and password) from a URL and return
1314  * it in a newly allocated string.
1315  */
1316 char *transport_anonymize_url(const char *url)
1317 {
1318         char *scheme_prefix, *anon_part;
1319         size_t anon_len, prefix_len = 0;
1320
1321         anon_part = strchr(url, '@');
1322         if (url_is_local_not_ssh(url) || !anon_part)
1323                 goto literal_copy;
1324
1325         anon_len = strlen(++anon_part);
1326         scheme_prefix = strstr(url, "://");
1327         if (!scheme_prefix) {
1328                 if (!strchr(anon_part, ':'))
1329                         /* cannot be "me@there:/path/name" */
1330                         goto literal_copy;
1331         } else {
1332                 const char *cp;
1333                 /* make sure scheme is reasonable */
1334                 for (cp = url; cp < scheme_prefix; cp++) {
1335                         switch (*cp) {
1336                                 /* RFC 1738 2.1 */
1337                         case '+': case '.': case '-':
1338                                 break; /* ok */
1339                         default:
1340                                 if (isalnum(*cp))
1341                                         break;
1342                                 /* it isn't */
1343                                 goto literal_copy;
1344                         }
1345                 }
1346                 /* @ past the first slash does not count */
1347                 cp = strchr(scheme_prefix + 3, '/');
1348                 if (cp && cp < anon_part)
1349                         goto literal_copy;
1350                 prefix_len = scheme_prefix - url + 3;
1351         }
1352         return xstrfmt("%.*s%.*s", (int)prefix_len, url,
1353                        (int)anon_len, anon_part);
1354 literal_copy:
1355         return xstrdup(url);
1356 }
1357
1358 static void read_alternate_refs(const char *path,
1359                                 alternate_ref_fn *cb,
1360                                 void *data)
1361 {
1362         struct child_process cmd = CHILD_PROCESS_INIT;
1363         struct strbuf line = STRBUF_INIT;
1364         FILE *fh;
1365
1366         cmd.git_cmd = 1;
1367         argv_array_pushf(&cmd.args, "--git-dir=%s", path);
1368         argv_array_push(&cmd.args, "for-each-ref");
1369         argv_array_push(&cmd.args, "--format=%(objectname) %(refname)");
1370         cmd.env = local_repo_env;
1371         cmd.out = -1;
1372
1373         if (start_command(&cmd))
1374                 return;
1375
1376         fh = xfdopen(cmd.out, "r");
1377         while (strbuf_getline_lf(&line, fh) != EOF) {
1378                 struct object_id oid;
1379
1380                 if (get_oid_hex(line.buf, &oid) ||
1381                     line.buf[GIT_SHA1_HEXSZ] != ' ') {
1382                         warning(_("invalid line while parsing alternate refs: %s"),
1383                                 line.buf);
1384                         break;
1385                 }
1386
1387                 cb(line.buf + GIT_SHA1_HEXSZ + 1, &oid, data);
1388         }
1389
1390         fclose(fh);
1391         finish_command(&cmd);
1392 }
1393
1394 struct alternate_refs_data {
1395         alternate_ref_fn *fn;
1396         void *data;
1397 };
1398
1399 static int refs_from_alternate_cb(struct alternate_object_database *e,
1400                                   void *data)
1401 {
1402         struct strbuf path = STRBUF_INIT;
1403         size_t base_len;
1404         struct alternate_refs_data *cb = data;
1405
1406         if (!strbuf_realpath(&path, e->path, 0))
1407                 goto out;
1408         if (!strbuf_strip_suffix(&path, "/objects"))
1409                 goto out;
1410         base_len = path.len;
1411
1412         /* Is this a git repository with refs? */
1413         strbuf_addstr(&path, "/refs");
1414         if (!is_directory(path.buf))
1415                 goto out;
1416         strbuf_setlen(&path, base_len);
1417
1418         read_alternate_refs(path.buf, cb->fn, cb->data);
1419
1420 out:
1421         strbuf_release(&path);
1422         return 0;
1423 }
1424
1425 void for_each_alternate_ref(alternate_ref_fn fn, void *data)
1426 {
1427         struct alternate_refs_data cb;
1428         cb.fn = fn;
1429         cb.data = data;
1430         foreach_alt_odb(refs_from_alternate_cb, &cb);
1431 }