git.oblomov.eu Git - git/blob - upload-pack.c

   1 #include "cache.h"
   2 #include "refs.h"
   3 #include "pkt-line.h"
   4 #include "sideband.h"
   5 #include "tag.h"
   6 #include "object.h"
   7 #include "commit.h"
   8 #include "exec_cmd.h"
   9 #include "diff.h"
  10 #include "revision.h"
  11 #include "list-objects.h"
  12 #include "run-command.h"
  13 #include "connect.h"
  14 #include "sigchain.h"
  15 #include "version.h"
  16 #include "string-list.h"
  17 #include "parse-options.h"
  18
  19 static const char * const upload_pack_usage[] = {
  20         N_("git upload-pack [<options>] <dir>"),
  21         NULL
  22 };
  23
  24 /* Remember to update object flag allocation in object.h */
  25 #define THEY_HAVE       (1u << 11)
  26 #define OUR_REF         (1u << 12)
  27 #define WANTED          (1u << 13)
  28 #define COMMON_KNOWN    (1u << 14)
  29 #define REACHABLE       (1u << 15)
  30
  31 #define SHALLOW         (1u << 16)
  32 #define NOT_SHALLOW     (1u << 17)
  33 #define CLIENT_SHALLOW  (1u << 18)
  34 #define HIDDEN_REF      (1u << 19)
  35
  36 static unsigned long oldest_have;
  37
  38 static int multi_ack;
  39 static int no_done;
  40 static int use_thin_pack, use_ofs_delta, use_include_tag;
  41 static int no_progress, daemon_mode;
  42 /* Allow specifying sha1 if it is a ref tip. */
  43 #define ALLOW_TIP_SHA1  01
  44 /* Allow request of a sha1 if it is reachable from a ref (possibly hidden ref). */
  45 #define ALLOW_REACHABLE_SHA1    02
  46 static unsigned int allow_unadvertised_object_request;
  47 static int shallow_nr;
  48 static struct object_array have_obj;
  49 static struct object_array want_obj;
  50 static struct object_array extra_edge_obj;
  51 static unsigned int timeout;
  52 static int keepalive = 5;
  53 /* 0 for no sideband,
  54  * otherwise maximum packet size (up to 65520 bytes).
  55  */
  56 static int use_sideband;
  57 static int advertise_refs;
  58 static int stateless_rpc;
  59
  60 static void reset_timeout(void)
  61 {
  62         alarm(timeout);
  63 }
  64
  65 static void send_client_data(int fd, const char *data, ssize_t sz)
  66 {
  67         if (use_sideband) {
  68                 send_sideband(1, fd, data, sz, use_sideband);
  69                 return;
  70         }
  71         if (fd == 3)
  72                 /* emergency quit */
  73                 fd = 2;
  74         if (fd == 2) {
  75                 /* XXX: are we happy to lose stuff here? */
  76                 xwrite(fd, data, sz);
  77                 return;
  78         }
  79         write_or_die(fd, data, sz);
  80 }
  81
  82 static int write_one_shallow(const struct commit_graft *graft, void *cb_data)
  83 {
  84         FILE *fp = cb_data;
  85         if (graft->nr_parent == -1)
  86                 fprintf(fp, "--shallow %s\n", oid_to_hex(&graft->oid));
  87         return 0;
  88 }
  89
  90 static void create_pack_file(void)
  91 {
  92         struct child_process pack_objects = CHILD_PROCESS_INIT;
  93         char data[8193], progress[128];
  94         char abort_msg[] = "aborting due to possible repository "
  95                 "corruption on the remote side.";
  96         int buffered = -1;
  97         ssize_t sz;
  98         int i;
  99         FILE *pipe_fd;
 100
 101         if (shallow_nr) {
 102                 argv_array_push(&pack_objects.args, "--shallow-file");
 103                 argv_array_push(&pack_objects.args, "");
 104         }
 105         argv_array_push(&pack_objects.args, "pack-objects");
 106         argv_array_push(&pack_objects.args, "--revs");
 107         if (use_thin_pack)
 108                 argv_array_push(&pack_objects.args, "--thin");
 109
 110         argv_array_push(&pack_objects.args, "--stdout");
 111         if (shallow_nr)
 112                 argv_array_push(&pack_objects.args, "--shallow");
 113         if (!no_progress)
 114                 argv_array_push(&pack_objects.args, "--progress");
 115         if (use_ofs_delta)
 116                 argv_array_push(&pack_objects.args, "--delta-base-offset");
 117         if (use_include_tag)
 118                 argv_array_push(&pack_objects.args, "--include-tag");
 119
 120         pack_objects.in = -1;
 121         pack_objects.out = -1;
 122         pack_objects.err = -1;
 123         pack_objects.git_cmd = 1;
 124
 125         if (start_command(&pack_objects))
 126                 die("git upload-pack: unable to fork git-pack-objects");
 127
 128         pipe_fd = xfdopen(pack_objects.in, "w");
 129
 130         if (shallow_nr)
 131                 for_each_commit_graft(write_one_shallow, pipe_fd);
 132
 133         for (i = 0; i < want_obj.nr; i++)
 134                 fprintf(pipe_fd, "%s\n",
 135                         oid_to_hex(&want_obj.objects[i].item->oid));
 136         fprintf(pipe_fd, "--not\n");
 137         for (i = 0; i < have_obj.nr; i++)
 138                 fprintf(pipe_fd, "%s\n",
 139                         oid_to_hex(&have_obj.objects[i].item->oid));
 140         for (i = 0; i < extra_edge_obj.nr; i++)
 141                 fprintf(pipe_fd, "%s\n",
 142                         oid_to_hex(&extra_edge_obj.objects[i].item->oid));
 143         fprintf(pipe_fd, "\n");
 144         fflush(pipe_fd);
 145         fclose(pipe_fd);
 146
 147         /* We read from pack_objects.err to capture stderr output for
 148          * progress bar, and pack_objects.out to capture the pack data.
 149          */
 150
 151         while (1) {
 152                 struct pollfd pfd[2];
 153                 int pe, pu, pollsize;
 154                 int ret;
 155
 156                 reset_timeout();
 157
 158                 pollsize = 0;
 159                 pe = pu = -1;
 160
 161                 if (0 <= pack_objects.out) {
 162                         pfd[pollsize].fd = pack_objects.out;
 163                         pfd[pollsize].events = POLLIN;
 164                         pu = pollsize;
 165                         pollsize++;
 166                 }
 167                 if (0 <= pack_objects.err) {
 168                         pfd[pollsize].fd = pack_objects.err;
 169                         pfd[pollsize].events = POLLIN;
 170                         pe = pollsize;
 171                         pollsize++;
 172                 }
 173
 174                 if (!pollsize)
 175                         break;
 176
 177                 ret = poll(pfd, pollsize,
 178                         keepalive < 0 ? -1 : 1000 * keepalive);
 179
 180                 if (ret < 0) {
 181                         if (errno != EINTR) {
 182                                 error_errno("poll failed, resuming");
 183                                 sleep(1);
 184                         }
 185                         continue;
 186                 }
 187                 if (0 <= pe && (pfd[pe].revents & (POLLIN|POLLHUP))) {
 188                         /* Status ready; we ship that in the side-band
 189                          * or dump to the standard error.
 190                          */
 191                         sz = xread(pack_objects.err, progress,
 192                                   sizeof(progress));
 193                         if (0 < sz)
 194                                 send_client_data(2, progress, sz);
 195                         else if (sz == 0) {
 196                                 close(pack_objects.err);
 197                                 pack_objects.err = -1;
 198                         }
 199                         else
 200                                 goto fail;
 201                         /* give priority to status messages */
 202                         continue;
 203                 }
 204                 if (0 <= pu && (pfd[pu].revents & (POLLIN|POLLHUP))) {
 205                         /* Data ready; we keep the last byte to ourselves
 206                          * in case we detect broken rev-list, so that we
 207                          * can leave the stream corrupted.  This is
 208                          * unfortunate -- unpack-objects would happily
 209                          * accept a valid packdata with trailing garbage,
 210                          * so appending garbage after we pass all the
 211                          * pack data is not good enough to signal
 212                          * breakage to downstream.
 213                          */
 214                         char *cp = data;
 215                         ssize_t outsz = 0;
 216                         if (0 <= buffered) {
 217                                 *cp++ = buffered;
 218                                 outsz++;
 219                         }
 220                         sz = xread(pack_objects.out, cp,
 221                                   sizeof(data) - outsz);
 222                         if (0 < sz)
 223                                 ;
 224                         else if (sz == 0) {
 225                                 close(pack_objects.out);
 226                                 pack_objects.out = -1;
 227                         }
 228                         else
 229                                 goto fail;
 230                         sz += outsz;
 231                         if (1 < sz) {
 232                                 buffered = data[sz-1] & 0xFF;
 233                                 sz--;
 234                         }
 235                         else
 236                                 buffered = -1;
 237                         send_client_data(1, data, sz);
 238                 }
 239
 240                 /*
 241                  * We hit the keepalive timeout without saying anything; send
 242                  * an empty message on the data sideband just to let the other
 243                  * side know we're still working on it, but don't have any data
 244                  * yet.
 245                  *
 246                  * If we don't have a sideband channel, there's no room in the
 247                  * protocol to say anything, so those clients are just out of
 248                  * luck.
 249                  */
 250                 if (!ret && use_sideband) {
 251                         static const char buf[] = "0005\1";
 252                         write_or_die(1, buf, 5);
 253                 }
 254         }
 255
 256         if (finish_command(&pack_objects)) {
 257                 error("git upload-pack: git-pack-objects died with error.");
 258                 goto fail;
 259         }
 260
 261         /* flush the data */
 262         if (0 <= buffered) {
 263                 data[0] = buffered;
 264                 send_client_data(1, data, 1);
 265                 fprintf(stderr, "flushed.\n");
 266         }
 267         if (use_sideband)
 268                 packet_flush(1);
 269         return;
 270
 271  fail:
 272         send_client_data(3, abort_msg, sizeof(abort_msg));
 273         die("git upload-pack: %s", abort_msg);
 274 }
 275
 276 static int got_sha1(char *hex, unsigned char *sha1)
 277 {
 278         struct object *o;
 279         int we_knew_they_have = 0;
 280
 281         if (get_sha1_hex(hex, sha1))
 282                 die("git upload-pack: expected SHA1 object, got '%s'", hex);
 283         if (!has_sha1_file(sha1))
 284                 return -1;
 285
 286         o = parse_object(sha1);
 287         if (!o)
 288                 die("oops (%s)", sha1_to_hex(sha1));
 289         if (o->type == OBJ_COMMIT) {
 290                 struct commit_list *parents;
 291                 struct commit *commit = (struct commit *)o;
 292                 if (o->flags & THEY_HAVE)
 293                         we_knew_they_have = 1;
 294                 else
 295                         o->flags |= THEY_HAVE;
 296                 if (!oldest_have || (commit->date < oldest_have))
 297                         oldest_have = commit->date;
 298                 for (parents = commit->parents;
 299                      parents;
 300                      parents = parents->next)
 301                         parents->item->object.flags |= THEY_HAVE;
 302         }
 303         if (!we_knew_they_have) {
 304                 add_object_array(o, NULL, &have_obj);
 305                 return 1;
 306         }
 307         return 0;
 308 }
 309
 310 static int reachable(struct commit *want)
 311 {
 312         struct commit_list *work = NULL;
 313
 314         commit_list_insert_by_date(want, &work);
 315         while (work) {
 316                 struct commit_list *list;
 317                 struct commit *commit = pop_commit(&work);
 318
 319                 if (commit->object.flags & THEY_HAVE) {
 320                         want->object.flags |= COMMON_KNOWN;
 321                         break;
 322                 }
 323                 if (!commit->object.parsed)
 324                         parse_object(commit->object.oid.hash);
 325                 if (commit->object.flags & REACHABLE)
 326                         continue;
 327                 commit->object.flags |= REACHABLE;
 328                 if (commit->date < oldest_have)
 329                         continue;
 330                 for (list = commit->parents; list; list = list->next) {
 331                         struct commit *parent = list->item;
 332                         if (!(parent->object.flags & REACHABLE))
 333                                 commit_list_insert_by_date(parent, &work);
 334                 }
 335         }
 336         want->object.flags |= REACHABLE;
 337         clear_commit_marks(want, REACHABLE);
 338         free_commit_list(work);
 339         return (want->object.flags & COMMON_KNOWN);
 340 }
 341
 342 static int ok_to_give_up(void)
 343 {
 344         int i;
 345
 346         if (!have_obj.nr)
 347                 return 0;
 348
 349         for (i = 0; i < want_obj.nr; i++) {
 350                 struct object *want = want_obj.objects[i].item;
 351
 352                 if (want->flags & COMMON_KNOWN)
 353                         continue;
 354                 want = deref_tag(want, "a want line", 0);
 355                 if (!want || want->type != OBJ_COMMIT) {
 356                         /* no way to tell if this is reachable by
 357                          * looking at the ancestry chain alone, so
 358                          * leave a note to ourselves not to worry about
 359                          * this object anymore.
 360                          */
 361                         want_obj.objects[i].item->flags |= COMMON_KNOWN;
 362                         continue;
 363                 }
 364                 if (!reachable((struct commit *)want))
 365                         return 0;
 366         }
 367         return 1;
 368 }
 369
 370 static int get_common_commits(void)
 371 {
 372         unsigned char sha1[20];
 373         char last_hex[41];
 374         int got_common = 0;
 375         int got_other = 0;
 376         int sent_ready = 0;
 377
 378         save_commit_buffer = 0;
 379
 380         for (;;) {
 381                 char *line = packet_read_line(0, NULL);
 382                 reset_timeout();
 383
 384                 if (!line) {
 385                         if (multi_ack == 2 && got_common
 386                             && !got_other && ok_to_give_up()) {
 387                                 sent_ready = 1;
 388                                 packet_write(1, "ACK %s ready\n", last_hex);
 389                         }
 390                         if (have_obj.nr == 0 || multi_ack)
 391                                 packet_write(1, "NAK\n");
 392
 393                         if (no_done && sent_ready) {
 394                                 packet_write(1, "ACK %s\n", last_hex);
 395                                 return 0;
 396                         }
 397                         if (stateless_rpc)
 398                                 exit(0);
 399                         got_common = 0;
 400                         got_other = 0;
 401                         continue;
 402                 }
 403                 if (starts_with(line, "have ")) {
 404                         switch (got_sha1(line+5, sha1)) {
 405                         case -1: /* they have what we do not */
 406                                 got_other = 1;
 407                                 if (multi_ack && ok_to_give_up()) {
 408                                         const char *hex = sha1_to_hex(sha1);
 409                                         if (multi_ack == 2) {
 410                                                 sent_ready = 1;
 411                                                 packet_write(1, "ACK %s ready\n", hex);
 412                                         } else
 413                                                 packet_write(1, "ACK %s continue\n", hex);
 414                                 }
 415                                 break;
 416                         default:
 417                                 got_common = 1;
 418                                 memcpy(last_hex, sha1_to_hex(sha1), 41);
 419                                 if (multi_ack == 2)
 420                                         packet_write(1, "ACK %s common\n", last_hex);
 421                                 else if (multi_ack)
 422                                         packet_write(1, "ACK %s continue\n", last_hex);
 423                                 else if (have_obj.nr == 1)
 424                                         packet_write(1, "ACK %s\n", last_hex);
 425                                 break;
 426                         }
 427                         continue;
 428                 }
 429                 if (!strcmp(line, "done")) {
 430                         if (have_obj.nr > 0) {
 431                                 if (multi_ack)
 432                                         packet_write(1, "ACK %s\n", last_hex);
 433                                 return 0;
 434                         }
 435                         packet_write(1, "NAK\n");
 436                         return -1;
 437                 }
 438                 die("git upload-pack: expected SHA1 list, got '%s'", line);
 439         }
 440 }
 441
 442 static int is_our_ref(struct object *o)
 443 {
 444         int allow_hidden_ref = (allow_unadvertised_object_request &
 445                         (ALLOW_TIP_SHA1 | ALLOW_REACHABLE_SHA1));
 446         return o->flags & ((allow_hidden_ref ? HIDDEN_REF : 0) | OUR_REF);
 447 }
 448
 449 static void check_non_tip(void)
 450 {
 451         static const char *argv[] = {
 452                 "rev-list", "--stdin", NULL,
 453         };
 454         static struct child_process cmd = CHILD_PROCESS_INIT;
 455         struct object *o;
 456         char namebuf[42]; /* ^ + SHA-1 + LF */
 457         int i;
 458
 459         /*
 460          * In the normal in-process case without
 461          * uploadpack.allowReachableSHA1InWant,
 462          * non-tip requests can never happen.
 463          */
 464         if (!stateless_rpc && !(allow_unadvertised_object_request & ALLOW_REACHABLE_SHA1))
 465                 goto error;
 466
 467         cmd.argv = argv;
 468         cmd.git_cmd = 1;
 469         cmd.no_stderr = 1;
 470         cmd.in = -1;
 471         cmd.out = -1;
 472
 473         if (start_command(&cmd))
 474                 goto error;
 475
 476         /*
 477          * If rev-list --stdin encounters an unknown commit, it
 478          * terminates, which will cause SIGPIPE in the write loop
 479          * below.
 480          */
 481         sigchain_push(SIGPIPE, SIG_IGN);
 482
 483         namebuf[0] = '^';
 484         namebuf[41] = '\n';
 485         for (i = get_max_object_index(); 0 < i; ) {
 486                 o = get_indexed_object(--i);
 487                 if (!o)
 488                         continue;
 489                 if (!is_our_ref(o))
 490                         continue;
 491                 memcpy(namebuf + 1, oid_to_hex(&o->oid), GIT_SHA1_HEXSZ);
 492                 if (write_in_full(cmd.in, namebuf, 42) < 0)
 493                         goto error;
 494         }
 495         namebuf[40] = '\n';
 496         for (i = 0; i < want_obj.nr; i++) {
 497                 o = want_obj.objects[i].item;
 498                 if (is_our_ref(o))
 499                         continue;
 500                 memcpy(namebuf, oid_to_hex(&o->oid), GIT_SHA1_HEXSZ);
 501                 if (write_in_full(cmd.in, namebuf, 41) < 0)
 502                         goto error;
 503         }
 504         close(cmd.in);
 505
 506         sigchain_pop(SIGPIPE);
 507
 508         /*
 509          * The commits out of the rev-list are not ancestors of
 510          * our ref.
 511          */
 512         i = read_in_full(cmd.out, namebuf, 1);
 513         if (i)
 514                 goto error;
 515         close(cmd.out);
 516
 517         /*
 518          * rev-list may have died by encountering a bad commit
 519          * in the history, in which case we do want to bail out
 520          * even when it showed no commit.
 521          */
 522         if (finish_command(&cmd))
 523                 goto error;
 524
 525         /* All the non-tip ones are ancestors of what we advertised */
 526         return;
 527
 528 error:
 529         /* Pick one of them (we know there at least is one) */
 530         for (i = 0; i < want_obj.nr; i++) {
 531                 o = want_obj.objects[i].item;
 532                 if (!is_our_ref(o))
 533                         die("git upload-pack: not our ref %s",
 534                             oid_to_hex(&o->oid));
 535         }
 536 }
 537
 538 static void receive_needs(void)
 539 {
 540         struct object_array shallows = OBJECT_ARRAY_INIT;
 541         int depth = 0;
 542         int has_non_tip = 0;
 543
 544         shallow_nr = 0;
 545         for (;;) {
 546                 struct object *o;
 547                 const char *features;
 548                 unsigned char sha1_buf[20];
 549                 char *line = packet_read_line(0, NULL);
 550                 reset_timeout();
 551                 if (!line)
 552                         break;
 553
 554                 if (starts_with(line, "shallow ")) {
 555                         unsigned char sha1[20];
 556                         struct object *object;
 557                         if (get_sha1_hex(line + 8, sha1))
 558                                 die("invalid shallow line: %s", line);
 559                         object = parse_object(sha1);
 560                         if (!object)
 561                                 continue;
 562                         if (object->type != OBJ_COMMIT)
 563                                 die("invalid shallow object %s", sha1_to_hex(sha1));
 564                         if (!(object->flags & CLIENT_SHALLOW)) {
 565                                 object->flags |= CLIENT_SHALLOW;
 566                                 add_object_array(object, NULL, &shallows);
 567                         }
 568                         continue;
 569                 }
 570                 if (starts_with(line, "deepen ")) {
 571                         char *end;
 572                         depth = strtol(line + 7, &end, 0);
 573                         if (end == line + 7 || depth <= 0)
 574                                 die("Invalid deepen: %s", line);
 575                         continue;
 576                 }
 577                 if (!starts_with(line, "want ") ||
 578                     get_sha1_hex(line+5, sha1_buf))
 579                         die("git upload-pack: protocol error, "
 580                             "expected to get sha, not '%s'", line);
 581
 582                 features = line + 45;
 583
 584                 if (parse_feature_request(features, "multi_ack_detailed"))
 585                         multi_ack = 2;
 586                 else if (parse_feature_request(features, "multi_ack"))
 587                         multi_ack = 1;
 588                 if (parse_feature_request(features, "no-done"))
 589                         no_done = 1;
 590                 if (parse_feature_request(features, "thin-pack"))
 591                         use_thin_pack = 1;
 592                 if (parse_feature_request(features, "ofs-delta"))
 593                         use_ofs_delta = 1;
 594                 if (parse_feature_request(features, "side-band-64k"))
 595                         use_sideband = LARGE_PACKET_MAX;
 596                 else if (parse_feature_request(features, "side-band"))
 597                         use_sideband = DEFAULT_PACKET_MAX;
 598                 if (parse_feature_request(features, "no-progress"))
 599                         no_progress = 1;
 600                 if (parse_feature_request(features, "include-tag"))
 601                         use_include_tag = 1;
 602
 603                 o = parse_object(sha1_buf);
 604                 if (!o)
 605                         die("git upload-pack: not our ref %s",
 606                             sha1_to_hex(sha1_buf));
 607                 if (!(o->flags & WANTED)) {
 608                         o->flags |= WANTED;
 609                         if (!is_our_ref(o))
 610                                 has_non_tip = 1;
 611                         add_object_array(o, NULL, &want_obj);
 612                 }
 613         }
 614
 615         /*
 616          * We have sent all our refs already, and the other end
 617          * should have chosen out of them. When we are operating
 618          * in the stateless RPC mode, however, their choice may
 619          * have been based on the set of older refs advertised
 620          * by another process that handled the initial request.
 621          */
 622         if (has_non_tip)
 623                 check_non_tip();
 624
 625         if (!use_sideband && daemon_mode)
 626                 no_progress = 1;
 627
 628         if (depth == 0 && shallows.nr == 0)
 629                 return;
 630         if (depth > 0) {
 631                 struct commit_list *result = NULL, *backup = NULL;
 632                 int i;
 633                 if (depth == INFINITE_DEPTH && !is_repository_shallow())
 634                         for (i = 0; i < shallows.nr; i++) {
 635                                 struct object *object = shallows.objects[i].item;
 636                                 object->flags |= NOT_SHALLOW;
 637                         }
 638                 else
 639                         backup = result =
 640                                 get_shallow_commits(&want_obj, depth,
 641                                                     SHALLOW, NOT_SHALLOW);
 642                 while (result) {
 643                         struct object *object = &result->item->object;
 644                         if (!(object->flags & (CLIENT_SHALLOW|NOT_SHALLOW))) {
 645                                 packet_write(1, "shallow %s",
 646                                                 oid_to_hex(&object->oid));
 647                                 register_shallow(object->oid.hash);
 648                                 shallow_nr++;
 649                         }
 650                         result = result->next;
 651                 }
 652                 free_commit_list(backup);
 653                 for (i = 0; i < shallows.nr; i++) {
 654                         struct object *object = shallows.objects[i].item;
 655                         if (object->flags & NOT_SHALLOW) {
 656                                 struct commit_list *parents;
 657                                 packet_write(1, "unshallow %s",
 658                                         oid_to_hex(&object->oid));
 659                                 object->flags &= ~CLIENT_SHALLOW;
 660                                 /* make sure the real parents are parsed */
 661                                 unregister_shallow(object->oid.hash);
 662                                 object->parsed = 0;
 663                                 parse_commit_or_die((struct commit *)object);
 664                                 parents = ((struct commit *)object)->parents;
 665                                 while (parents) {
 666                                         add_object_array(&parents->item->object,
 667                                                         NULL, &want_obj);
 668                                         parents = parents->next;
 669                                 }
 670                                 add_object_array(object, NULL, &extra_edge_obj);
 671                         }
 672                         /* make sure commit traversal conforms to client */
 673                         register_shallow(object->oid.hash);
 674                 }
 675                 packet_flush(1);
 676         } else
 677                 if (shallows.nr > 0) {
 678                         int i;
 679                         for (i = 0; i < shallows.nr; i++)
 680                                 register_shallow(shallows.objects[i].item->oid.hash);
 681                 }
 682
 683         shallow_nr += shallows.nr;
 684         free(shallows.objects);
 685 }
 686
 687 /* return non-zero if the ref is hidden, otherwise 0 */
 688 static int mark_our_ref(const char *refname, const char *refname_full,
 689                         const struct object_id *oid)
 690 {
 691         struct object *o = lookup_unknown_object(oid->hash);
 692
 693         if (ref_is_hidden(refname, refname_full)) {
 694                 o->flags |= HIDDEN_REF;
 695                 return 1;
 696         }
 697         o->flags |= OUR_REF;
 698         return 0;
 699 }
 700
 701 static int check_ref(const char *refname_full, const struct object_id *oid,
 702                      int flag, void *cb_data)
 703 {
 704         const char *refname = strip_namespace(refname_full);
 705
 706         mark_our_ref(refname, refname_full, oid);
 707         return 0;
 708 }
 709
 710 static void format_symref_info(struct strbuf *buf, struct string_list *symref)
 711 {
 712         struct string_list_item *item;
 713
 714         if (!symref->nr)
 715                 return;
 716         for_each_string_list_item(item, symref)
 717                 strbuf_addf(buf, " symref=%s:%s", item->string, (char *)item->util);
 718 }
 719
 720 static int send_ref(const char *refname, const struct object_id *oid,
 721                     int flag, void *cb_data)
 722 {
 723         static const char *capabilities = "multi_ack thin-pack side-band"
 724                 " side-band-64k ofs-delta shallow no-progress"
 725                 " include-tag multi_ack_detailed";
 726         const char *refname_nons = strip_namespace(refname);
 727         struct object_id peeled;
 728
 729         if (mark_our_ref(refname_nons, refname, oid))
 730                 return 0;
 731
 732         if (capabilities) {
 733                 struct strbuf symref_info = STRBUF_INIT;
 734
 735                 format_symref_info(&symref_info, cb_data);
 736                 packet_write(1, "%s %s%c%s%s%s%s%s agent=%s\n",
 737                              oid_to_hex(oid), refname_nons,
 738                              0, capabilities,
 739                              (allow_unadvertised_object_request & ALLOW_TIP_SHA1) ?
 740                                      " allow-tip-sha1-in-want" : "",
 741                              (allow_unadvertised_object_request & ALLOW_REACHABLE_SHA1) ?
 742                                      " allow-reachable-sha1-in-want" : "",
 743                              stateless_rpc ? " no-done" : "",
 744                              symref_info.buf,
 745                              git_user_agent_sanitized());
 746                 strbuf_release(&symref_info);
 747         } else {
 748                 packet_write(1, "%s %s\n", oid_to_hex(oid), refname_nons);
 749         }
 750         capabilities = NULL;
 751         if (!peel_ref(refname, peeled.hash))
 752                 packet_write(1, "%s %s^{}\n", oid_to_hex(&peeled), refname_nons);
 753         return 0;
 754 }
 755
 756 static int find_symref(const char *refname, const struct object_id *oid,
 757                        int flag, void *cb_data)
 758 {
 759         const char *symref_target;
 760         struct string_list_item *item;
 761         struct object_id unused;
 762
 763         if ((flag & REF_ISSYMREF) == 0)
 764                 return 0;
 765         symref_target = resolve_ref_unsafe(refname, 0, unused.hash, &flag);
 766         if (!symref_target || (flag & REF_ISSYMREF) == 0)
 767                 die("'%s' is a symref but it is not?", refname);
 768         item = string_list_append(cb_data, refname);
 769         item->util = xstrdup(symref_target);
 770         return 0;
 771 }
 772
 773 static void upload_pack(void)
 774 {
 775         struct string_list symref = STRING_LIST_INIT_DUP;
 776
 777         head_ref_namespaced(find_symref, &symref);
 778
 779         if (advertise_refs || !stateless_rpc) {
 780                 reset_timeout();
 781                 head_ref_namespaced(send_ref, &symref);
 782                 for_each_namespaced_ref(send_ref, &symref);
 783                 advertise_shallow_grafts(1);
 784                 packet_flush(1);
 785         } else {
 786                 head_ref_namespaced(check_ref, NULL);
 787                 for_each_namespaced_ref(check_ref, NULL);
 788         }
 789         string_list_clear(&symref, 1);
 790         if (advertise_refs)
 791                 return;
 792
 793         receive_needs();
 794         if (want_obj.nr) {
 795                 get_common_commits();
 796                 create_pack_file();
 797         }
 798 }
 799
 800 static int upload_pack_config(const char *var, const char *value, void *unused)
 801 {
 802         if (!strcmp("uploadpack.allowtipsha1inwant", var)) {
 803                 if (git_config_bool(var, value))
 804                         allow_unadvertised_object_request |= ALLOW_TIP_SHA1;
 805                 else
 806                         allow_unadvertised_object_request &= ~ALLOW_TIP_SHA1;
 807         } else if (!strcmp("uploadpack.allowreachablesha1inwant", var)) {
 808                 if (git_config_bool(var, value))
 809                         allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
 810                 else
 811                         allow_unadvertised_object_request &= ~ALLOW_REACHABLE_SHA1;
 812         } else if (!strcmp("uploadpack.keepalive", var)) {
 813                 keepalive = git_config_int(var, value);
 814                 if (!keepalive)
 815                         keepalive = -1;
 816         }
 817         return parse_hide_refs_config(var, value, "uploadpack");
 818 }
 819
 820 int main(int argc, const char **argv)
 821 {
 822         const char *dir;
 823         int strict = 0;
 824         struct option options[] = {
 825                 OPT_BOOL(0, "stateless-rpc", &stateless_rpc,
 826                          N_("quit after a single request/response exchange")),
 827                 OPT_BOOL(0, "advertise-refs", &advertise_refs,
 828                          N_("exit immediately after intial ref advertisement")),
 829                 OPT_BOOL(0, "strict", &strict,
 830                          N_("do not try <directory>/.git/ if <directory> is no Git directory")),
 831                 OPT_INTEGER(0, "timeout", &timeout,
 832                             N_("interrupt transfer after <n> seconds of inactivity")),
 833                 OPT_END()
 834         };
 835
 836         git_setup_gettext();
 837
 838         packet_trace_identity("upload-pack");
 839         git_extract_argv0_path(argv[0]);
 840         check_replace_refs = 0;
 841
 842         argc = parse_options(argc, argv, NULL, options, upload_pack_usage, 0);
 843
 844         if (argc != 1)
 845                 usage_with_options(upload_pack_usage, options);
 846
 847         if (timeout)
 848                 daemon_mode = 1;
 849
 850         setup_path();
 851
 852         dir = argv[0];
 853
 854         if (!enter_repo(dir, strict))
 855                 die("'%s' does not appear to be a git repository", dir);
 856
 857         git_config(upload_pack_config, NULL);
 858         upload_pack();
 859         return 0;
 860 }