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 "argv-array.h"
  18
  19 static const char upload_pack_usage[] = "git upload-pack [--strict] [--timeout=<n>] <dir>";
  20
  21 /* Remember to update object flag allocation in object.h */
  22 #define THEY_HAVE       (1u << 11)
  23 #define OUR_REF         (1u << 12)
  24 #define WANTED          (1u << 13)
  25 #define COMMON_KNOWN    (1u << 14)
  26 #define REACHABLE       (1u << 15)
  27
  28 #define SHALLOW         (1u << 16)
  29 #define NOT_SHALLOW     (1u << 17)
  30 #define CLIENT_SHALLOW  (1u << 18)
  31 #define HIDDEN_REF      (1u << 19)
  32
  33 static unsigned long oldest_have;
  34
  35 static int multi_ack;
  36 static int no_done;
  37 static int use_thin_pack, use_ofs_delta, use_include_tag;
  38 static int no_progress, daemon_mode;
  39 /* Allow specifying sha1 if it is a ref tip. */
  40 #define ALLOW_TIP_SHA1  01
  41 /* Allow request of a sha1 if it is reachable from a ref (possibly hidden ref). */
  42 #define ALLOW_REACHABLE_SHA1    02
  43 static unsigned int allow_unadvertised_object_request;
  44 static int shallow_nr;
  45 static struct object_array have_obj;
  46 static struct object_array want_obj;
  47 static struct object_array extra_edge_obj;
  48 static unsigned int timeout;
  49 static int keepalive = 5;
  50 /* 0 for no sideband,
  51  * otherwise maximum packet size (up to 65520 bytes).
  52  */
  53 static int use_sideband;
  54 static int advertise_refs;
  55 static int stateless_rpc;
  56
  57 static void reset_timeout(void)
  58 {
  59         alarm(timeout);
  60 }
  61
  62 static ssize_t send_client_data(int fd, const char *data, ssize_t sz)
  63 {
  64         if (use_sideband)
  65                 return send_sideband(1, fd, data, sz, use_sideband);
  66         if (fd == 3)
  67                 /* emergency quit */
  68                 fd = 2;
  69         if (fd == 2) {
  70                 /* XXX: are we happy to lose stuff here? */
  71                 xwrite(fd, data, sz);
  72                 return sz;
  73         }
  74         write_or_die(fd, data, sz);
  75         return sz;
  76 }
  77
  78 static int write_one_shallow(const struct commit_graft *graft, void *cb_data)
  79 {
  80         FILE *fp = cb_data;
  81         if (graft->nr_parent == -1)
  82                 fprintf(fp, "--shallow %s\n", oid_to_hex(&graft->oid));
  83         return 0;
  84 }
  85
  86 static void create_pack_file(void)
  87 {
  88         struct child_process pack_objects = CHILD_PROCESS_INIT;
  89         char data[8193], progress[128];
  90         char abort_msg[] = "aborting due to possible repository "
  91                 "corruption on the remote side.";
  92         int buffered = -1;
  93         ssize_t sz;
  94         const char *argv[13];
  95         int i, arg = 0;
  96         FILE *pipe_fd;
  97
  98         if (shallow_nr) {
  99                 argv[arg++] = "--shallow-file";
 100                 argv[arg++] = "";
 101         }
 102         argv[arg++] = "pack-objects";
 103         argv[arg++] = "--revs";
 104         if (use_thin_pack)
 105                 argv[arg++] = "--thin";
 106
 107         argv[arg++] = "--stdout";
 108         if (shallow_nr)
 109                 argv[arg++] = "--shallow";
 110         if (!no_progress)
 111                 argv[arg++] = "--progress";
 112         if (use_ofs_delta)
 113                 argv[arg++] = "--delta-base-offset";
 114         if (use_include_tag)
 115                 argv[arg++] = "--include-tag";
 116         argv[arg++] = NULL;
 117
 118         pack_objects.in = -1;
 119         pack_objects.out = -1;
 120         pack_objects.err = -1;
 121         pack_objects.git_cmd = 1;
 122         pack_objects.argv = argv;
 123
 124         if (start_command(&pack_objects))
 125                 die("git upload-pack: unable to fork git-pack-objects");
 126
 127         pipe_fd = xfdopen(pack_objects.in, "w");
 128
 129         if (shallow_nr)
 130                 for_each_commit_graft(write_one_shallow, pipe_fd);
 131
 132         for (i = 0; i < want_obj.nr; i++)
 133                 fprintf(pipe_fd, "%s\n",
 134                         oid_to_hex(&want_obj.objects[i].item->oid));
 135         fprintf(pipe_fd, "--not\n");
 136         for (i = 0; i < have_obj.nr; i++)
 137                 fprintf(pipe_fd, "%s\n",
 138                         oid_to_hex(&have_obj.objects[i].item->oid));
 139         for (i = 0; i < extra_edge_obj.nr; i++)
 140                 fprintf(pipe_fd, "%s\n",
 141                         oid_to_hex(&extra_edge_obj.objects[i].item->oid));
 142         fprintf(pipe_fd, "\n");
 143         fflush(pipe_fd);
 144         fclose(pipe_fd);
 145
 146         /* We read from pack_objects.err to capture stderr output for
 147          * progress bar, and pack_objects.out to capture the pack data.
 148          */
 149
 150         while (1) {
 151                 struct pollfd pfd[2];
 152                 int pe, pu, pollsize;
 153                 int ret;
 154
 155                 reset_timeout();
 156
 157                 pollsize = 0;
 158                 pe = pu = -1;
 159
 160                 if (0 <= pack_objects.out) {
 161                         pfd[pollsize].fd = pack_objects.out;
 162                         pfd[pollsize].events = POLLIN;
 163                         pu = pollsize;
 164                         pollsize++;
 165                 }
 166                 if (0 <= pack_objects.err) {
 167                         pfd[pollsize].fd = pack_objects.err;
 168                         pfd[pollsize].events = POLLIN;
 169                         pe = pollsize;
 170                         pollsize++;
 171                 }
 172
 173                 if (!pollsize)
 174                         break;
 175
 176                 ret = poll(pfd, pollsize,
 177                         keepalive < 0 ? -1 : 1000 * keepalive);
 178
 179                 if (ret < 0) {
 180                         if (errno != EINTR) {
 181                                 error("poll failed, resuming: %s",
 182                                       strerror(errno));
 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                         sz = send_client_data(1, data, sz);
 238                         if (sz < 0)
 239                                 goto fail;
 240                 }
 241
 242                 /*
 243                  * We hit the keepalive timeout without saying anything; send
 244                  * an empty message on the data sideband just to let the other
 245                  * side know we're still working on it, but don't have any data
 246                  * yet.
 247                  *
 248                  * If we don't have a sideband channel, there's no room in the
 249                  * protocol to say anything, so those clients are just out of
 250                  * luck.
 251                  */
 252                 if (!ret && use_sideband) {
 253                         static const char buf[] = "0005\1";
 254                         write_or_die(1, buf, 5);
 255                 }
 256         }
 257
 258         if (finish_command(&pack_objects)) {
 259                 error("git upload-pack: git-pack-objects died with error.");
 260                 goto fail;
 261         }
 262
 263         /* flush the data */
 264         if (0 <= buffered) {
 265                 data[0] = buffered;
 266                 sz = send_client_data(1, data, 1);
 267                 if (sz < 0)
 268                         goto fail;
 269                 fprintf(stderr, "flushed.\n");
 270         }
 271         if (use_sideband)
 272                 packet_flush(1);
 273         return;
 274
 275  fail:
 276         send_client_data(3, abort_msg, sizeof(abort_msg));
 277         die("git upload-pack: %s", abort_msg);
 278 }
 279
 280 static int got_sha1(const char *hex, unsigned char *sha1)
 281 {
 282         struct object *o;
 283         int we_knew_they_have = 0;
 284
 285         if (get_sha1_hex(hex, sha1))
 286                 die("git upload-pack: expected SHA1 object, got '%s'", hex);
 287         if (!has_sha1_file(sha1))
 288                 return -1;
 289
 290         o = parse_object(sha1);
 291         if (!o)
 292                 die("oops (%s)", sha1_to_hex(sha1));
 293         if (o->type == OBJ_COMMIT) {
 294                 struct commit_list *parents;
 295                 struct commit *commit = (struct commit *)o;
 296                 if (o->flags & THEY_HAVE)
 297                         we_knew_they_have = 1;
 298                 else
 299                         o->flags |= THEY_HAVE;
 300                 if (!oldest_have || (commit->date < oldest_have))
 301                         oldest_have = commit->date;
 302                 for (parents = commit->parents;
 303                      parents;
 304                      parents = parents->next)
 305                         parents->item->object.flags |= THEY_HAVE;
 306         }
 307         if (!we_knew_they_have) {
 308                 add_object_array(o, NULL, &have_obj);
 309                 return 1;
 310         }
 311         return 0;
 312 }
 313
 314 static int reachable(struct commit *want)
 315 {
 316         struct commit_list *work = NULL;
 317
 318         commit_list_insert_by_date(want, &work);
 319         while (work) {
 320                 struct commit_list *list;
 321                 struct commit *commit = pop_commit(&work);
 322
 323                 if (commit->object.flags & THEY_HAVE) {
 324                         want->object.flags |= COMMON_KNOWN;
 325                         break;
 326                 }
 327                 if (!commit->object.parsed)
 328                         parse_object(commit->object.oid.hash);
 329                 if (commit->object.flags & REACHABLE)
 330                         continue;
 331                 commit->object.flags |= REACHABLE;
 332                 if (commit->date < oldest_have)
 333                         continue;
 334                 for (list = commit->parents; list; list = list->next) {
 335                         struct commit *parent = list->item;
 336                         if (!(parent->object.flags & REACHABLE))
 337                                 commit_list_insert_by_date(parent, &work);
 338                 }
 339         }
 340         want->object.flags |= REACHABLE;
 341         clear_commit_marks(want, REACHABLE);
 342         free_commit_list(work);
 343         return (want->object.flags & COMMON_KNOWN);
 344 }
 345
 346 static int ok_to_give_up(void)
 347 {
 348         int i;
 349
 350         if (!have_obj.nr)
 351                 return 0;
 352
 353         for (i = 0; i < want_obj.nr; i++) {
 354                 struct object *want = want_obj.objects[i].item;
 355
 356                 if (want->flags & COMMON_KNOWN)
 357                         continue;
 358                 want = deref_tag(want, "a want line", 0);
 359                 if (!want || want->type != OBJ_COMMIT) {
 360                         /* no way to tell if this is reachable by
 361                          * looking at the ancestry chain alone, so
 362                          * leave a note to ourselves not to worry about
 363                          * this object anymore.
 364                          */
 365                         want_obj.objects[i].item->flags |= COMMON_KNOWN;
 366                         continue;
 367                 }
 368                 if (!reachable((struct commit *)want))
 369                         return 0;
 370         }
 371         return 1;
 372 }
 373
 374 static int get_common_commits(void)
 375 {
 376         unsigned char sha1[20];
 377         char last_hex[41];
 378         int got_common = 0;
 379         int got_other = 0;
 380         int sent_ready = 0;
 381
 382         save_commit_buffer = 0;
 383
 384         for (;;) {
 385                 char *line = packet_read_line(0, NULL);
 386                 const char *arg;
 387
 388                 reset_timeout();
 389
 390                 if (!line) {
 391                         if (multi_ack == 2 && got_common
 392                             && !got_other && ok_to_give_up()) {
 393                                 sent_ready = 1;
 394                                 packet_write(1, "ACK %s ready\n", last_hex);
 395                         }
 396                         if (have_obj.nr == 0 || multi_ack)
 397                                 packet_write(1, "NAK\n");
 398
 399                         if (no_done && sent_ready) {
 400                                 packet_write(1, "ACK %s\n", last_hex);
 401                                 return 0;
 402                         }
 403                         if (stateless_rpc)
 404                                 exit(0);
 405                         got_common = 0;
 406                         got_other = 0;
 407                         continue;
 408                 }
 409                 if (skip_prefix(line, "have ", &arg)) {
 410                         switch (got_sha1(arg, sha1)) {
 411                         case -1: /* they have what we do not */
 412                                 got_other = 1;
 413                                 if (multi_ack && ok_to_give_up()) {
 414                                         const char *hex = sha1_to_hex(sha1);
 415                                         if (multi_ack == 2) {
 416                                                 sent_ready = 1;
 417                                                 packet_write(1, "ACK %s ready\n", hex);
 418                                         } else
 419                                                 packet_write(1, "ACK %s continue\n", hex);
 420                                 }
 421                                 break;
 422                         default:
 423                                 got_common = 1;
 424                                 memcpy(last_hex, sha1_to_hex(sha1), 41);
 425                                 if (multi_ack == 2)
 426                                         packet_write(1, "ACK %s common\n", last_hex);
 427                                 else if (multi_ack)
 428                                         packet_write(1, "ACK %s continue\n", last_hex);
 429                                 else if (have_obj.nr == 1)
 430                                         packet_write(1, "ACK %s\n", last_hex);
 431                                 break;
 432                         }
 433                         continue;
 434                 }
 435                 if (!strcmp(line, "done")) {
 436                         if (have_obj.nr > 0) {
 437                                 if (multi_ack)
 438                                         packet_write(1, "ACK %s\n", last_hex);
 439                                 return 0;
 440                         }
 441                         packet_write(1, "NAK\n");
 442                         return -1;
 443                 }
 444                 die("git upload-pack: expected SHA1 list, got '%s'", line);
 445         }
 446 }
 447
 448 static int is_our_ref(struct object *o)
 449 {
 450         int allow_hidden_ref = (allow_unadvertised_object_request &
 451                         (ALLOW_TIP_SHA1 | ALLOW_REACHABLE_SHA1));
 452         return o->flags & ((allow_hidden_ref ? HIDDEN_REF : 0) | OUR_REF);
 453 }
 454
 455 static int has_unreachable(struct object_array *src)
 456 {
 457         static const char *argv[] = {
 458                 "rev-list", "--stdin", NULL,
 459         };
 460         static struct child_process cmd = CHILD_PROCESS_INIT;
 461         struct object *o;
 462         char namebuf[42]; /* ^ + SHA-1 + LF */
 463         int i;
 464
 465         cmd.argv = argv;
 466         cmd.git_cmd = 1;
 467         cmd.no_stderr = 1;
 468         cmd.in = -1;
 469         cmd.out = -1;
 470
 471         /*
 472          * If the next rev-list --stdin encounters an unknown commit,
 473          * it terminates, which will cause SIGPIPE in the write loop
 474          * below.
 475          */
 476         sigchain_push(SIGPIPE, SIG_IGN);
 477
 478         if (start_command(&cmd))
 479                 goto error;
 480
 481         namebuf[0] = '^';
 482         namebuf[41] = '\n';
 483         for (i = get_max_object_index(); 0 < i; ) {
 484                 o = get_indexed_object(--i);
 485                 if (!o)
 486                         continue;
 487                 if (!is_our_ref(o))
 488                         continue;
 489                 memcpy(namebuf + 1, oid_to_hex(&o->oid), GIT_SHA1_HEXSZ);
 490                 if (write_in_full(cmd.in, namebuf, 42) < 0)
 491                         goto error;
 492         }
 493         namebuf[40] = '\n';
 494         for (i = 0; i < src->nr; i++) {
 495                 o = src->objects[i].item;
 496                 if (is_our_ref(o))
 497                         continue;
 498                 memcpy(namebuf, oid_to_hex(&o->oid), GIT_SHA1_HEXSZ);
 499                 if (write_in_full(cmd.in, namebuf, 41) < 0)
 500                         goto error;
 501         }
 502         close(cmd.in);
 503         cmd.in = -1;
 504
 505         /*
 506          * The commits out of the rev-list are not ancestors of
 507          * our ref.
 508          */
 509         i = read_in_full(cmd.out, namebuf, 1);
 510         if (i)
 511                 goto error;
 512         close(cmd.out);
 513         cmd.out = -1;
 514
 515         /*
 516          * rev-list may have died by encountering a bad commit
 517          * in the history, in which case we do want to bail out
 518          * even when it showed no commit.
 519          */
 520         if (finish_command(&cmd))
 521                 goto error;
 522
 523         sigchain_pop(SIGPIPE);
 524
 525         /* All the non-tip ones are ancestors of what we advertised */
 526         return 0;
 527
 528 error:
 529         sigchain_pop(SIGPIPE);
 530
 531         if (cmd.in >= 0)
 532                 close(cmd.in);
 533         if (cmd.out >= 0)
 534                 close(cmd.out);
 535         return 1;
 536 }
 537
 538 static void check_non_tip(void)
 539 {
 540         int i;
 541
 542         /*
 543          * In the normal in-process case without
 544          * uploadpack.allowReachableSHA1InWant,
 545          * non-tip requests can never happen.
 546          */
 547         if (!stateless_rpc && !(allow_unadvertised_object_request & ALLOW_REACHABLE_SHA1))
 548                 goto error;
 549         if (!has_unreachable(&want_obj))
 550                 /* All the non-tip ones are ancestors of what we advertised */
 551                 return;
 552
 553 error:
 554         /* Pick one of them (we know there at least is one) */
 555         for (i = 0; i < want_obj.nr; i++) {
 556                 struct object *o = want_obj.objects[i].item;
 557                 if (!is_our_ref(o))
 558                         die("git upload-pack: not our ref %s",
 559                             oid_to_hex(&o->oid));
 560         }
 561 }
 562
 563 static void send_shallow(struct commit_list *result)
 564 {
 565         while (result) {
 566                 struct object *object = &result->item->object;
 567                 if (!(object->flags & (CLIENT_SHALLOW|NOT_SHALLOW))) {
 568                         packet_write(1, "shallow %s",
 569                                      oid_to_hex(&object->oid));
 570                         register_shallow(object->oid.hash);
 571                         shallow_nr++;
 572                 }
 573                 result = result->next;
 574         }
 575 }
 576
 577 static void send_unshallow(const struct object_array *shallows)
 578 {
 579         int i;
 580
 581         for (i = 0; i < shallows->nr; i++) {
 582                 struct object *object = shallows->objects[i].item;
 583                 if (object->flags & NOT_SHALLOW) {
 584                         struct commit_list *parents;
 585                         packet_write(1, "unshallow %s",
 586                                      oid_to_hex(&object->oid));
 587                         object->flags &= ~CLIENT_SHALLOW;
 588                         /*
 589                          * We want to _register_ "object" as shallow, but we
 590                          * also need to traverse object's parents to deepen a
 591                          * shallow clone. Unregister it for now so we can
 592                          * parse and add the parents to the want list, then
 593                          * re-register it.
 594                          */
 595                         unregister_shallow(object->oid.hash);
 596                         object->parsed = 0;
 597                         parse_commit_or_die((struct commit *)object);
 598                         parents = ((struct commit *)object)->parents;
 599                         while (parents) {
 600                                 add_object_array(&parents->item->object,
 601                                                  NULL, &want_obj);
 602                                 parents = parents->next;
 603                         }
 604                         add_object_array(object, NULL, &extra_edge_obj);
 605                 }
 606                 /* make sure commit traversal conforms to client */
 607                 register_shallow(object->oid.hash);
 608         }
 609 }
 610
 611 static void deepen(int depth, const struct object_array *shallows)
 612 {
 613         if (depth == INFINITE_DEPTH && !is_repository_shallow()) {
 614                 int i;
 615
 616                 for (i = 0; i < shallows->nr; i++) {
 617                         struct object *object = shallows->objects[i].item;
 618                         object->flags |= NOT_SHALLOW;
 619                 }
 620         } else {
 621                 struct commit_list *result;
 622
 623                 result = get_shallow_commits(&want_obj, depth,
 624                                              SHALLOW, NOT_SHALLOW);
 625                 send_shallow(result);
 626                 free_commit_list(result);
 627         }
 628
 629         send_unshallow(shallows);
 630         packet_flush(1);
 631 }
 632
 633 static void deepen_by_rev_list(int ac, const char **av,
 634                                struct object_array *shallows)
 635 {
 636         struct commit_list *result;
 637
 638         result = get_shallow_commits_by_rev_list(ac, av, SHALLOW, NOT_SHALLOW);
 639         send_shallow(result);
 640         free_commit_list(result);
 641         send_unshallow(shallows);
 642         packet_flush(1);
 643 }
 644
 645 static void receive_needs(void)
 646 {
 647         struct object_array shallows = OBJECT_ARRAY_INIT;
 648         struct string_list deepen_not = STRING_LIST_INIT_DUP;
 649         int depth = 0;
 650         int has_non_tip = 0;
 651         unsigned long deepen_since = 0;
 652         int deepen_rev_list = 0;
 653
 654         shallow_nr = 0;
 655         for (;;) {
 656                 struct object *o;
 657                 const char *features;
 658                 unsigned char sha1_buf[20];
 659                 char *line = packet_read_line(0, NULL);
 660                 const char *arg;
 661
 662                 reset_timeout();
 663                 if (!line)
 664                         break;
 665
 666                 if (skip_prefix(line, "shallow ", &arg)) {
 667                         unsigned char sha1[20];
 668                         struct object *object;
 669                         if (get_sha1_hex(arg, sha1))
 670                                 die("invalid shallow line: %s", line);
 671                         object = parse_object(sha1);
 672                         if (!object)
 673                                 continue;
 674                         if (object->type != OBJ_COMMIT)
 675                                 die("invalid shallow object %s", sha1_to_hex(sha1));
 676                         if (!(object->flags & CLIENT_SHALLOW)) {
 677                                 object->flags |= CLIENT_SHALLOW;
 678                                 add_object_array(object, NULL, &shallows);
 679                         }
 680                         continue;
 681                 }
 682                 if (skip_prefix(line, "deepen ", &arg)) {
 683                         char *end = NULL;
 684                         depth = strtol(arg, &end, 0);
 685                         if (!end || *end || depth <= 0)
 686                                 die("Invalid deepen: %s", line);
 687                         continue;
 688                 }
 689                 if (skip_prefix(line, "deepen-since ", &arg)) {
 690                         char *end = NULL;
 691                         deepen_since = strtoul(arg, &end, 0);
 692                         if (!end || *end || !deepen_since ||
 693                             /* revisions.c's max_age -1 is special */
 694                             deepen_since == -1)
 695                                 die("Invalid deepen-since: %s", line);
 696                         deepen_rev_list = 1;
 697                         continue;
 698                 }
 699                 if (skip_prefix(line, "deepen-not ", &arg)) {
 700                         char *ref = NULL;
 701                         unsigned char sha1[20];
 702                         if (expand_ref(arg, strlen(arg), sha1, &ref) != 1)
 703                                 die("git upload-pack: ambiguous deepen-not: %s", line);
 704                         string_list_append(&deepen_not, ref);
 705                         free(ref);
 706                         deepen_rev_list = 1;
 707                         continue;
 708                 }
 709                 if (!skip_prefix(line, "want ", &arg) ||
 710                     get_sha1_hex(arg, sha1_buf))
 711                         die("git upload-pack: protocol error, "
 712                             "expected to get sha, not '%s'", line);
 713
 714                 features = arg + 40;
 715
 716                 if (parse_feature_request(features, "multi_ack_detailed"))
 717                         multi_ack = 2;
 718                 else if (parse_feature_request(features, "multi_ack"))
 719                         multi_ack = 1;
 720                 if (parse_feature_request(features, "no-done"))
 721                         no_done = 1;
 722                 if (parse_feature_request(features, "thin-pack"))
 723                         use_thin_pack = 1;
 724                 if (parse_feature_request(features, "ofs-delta"))
 725                         use_ofs_delta = 1;
 726                 if (parse_feature_request(features, "side-band-64k"))
 727                         use_sideband = LARGE_PACKET_MAX;
 728                 else if (parse_feature_request(features, "side-band"))
 729                         use_sideband = DEFAULT_PACKET_MAX;
 730                 if (parse_feature_request(features, "no-progress"))
 731                         no_progress = 1;
 732                 if (parse_feature_request(features, "include-tag"))
 733                         use_include_tag = 1;
 734
 735                 o = parse_object(sha1_buf);
 736                 if (!o)
 737                         die("git upload-pack: not our ref %s",
 738                             sha1_to_hex(sha1_buf));
 739                 if (!(o->flags & WANTED)) {
 740                         o->flags |= WANTED;
 741                         if (!is_our_ref(o))
 742                                 has_non_tip = 1;
 743                         add_object_array(o, NULL, &want_obj);
 744                 }
 745         }
 746
 747         /*
 748          * We have sent all our refs already, and the other end
 749          * should have chosen out of them. When we are operating
 750          * in the stateless RPC mode, however, their choice may
 751          * have been based on the set of older refs advertised
 752          * by another process that handled the initial request.
 753          */
 754         if (has_non_tip)
 755                 check_non_tip();
 756
 757         if (!use_sideband && daemon_mode)
 758                 no_progress = 1;
 759
 760         if (depth == 0 && !deepen_rev_list && shallows.nr == 0)
 761                 return;
 762         if (depth > 0 && deepen_rev_list)
 763                 die("git upload-pack: deepen and deepen-since (or deepen-not) cannot be used together");
 764         if (depth > 0)
 765                 deepen(depth, &shallows);
 766         else if (deepen_rev_list) {
 767                 struct argv_array av = ARGV_ARRAY_INIT;
 768                 int i;
 769
 770                 argv_array_push(&av, "rev-list");
 771                 if (deepen_since)
 772                         argv_array_pushf(&av, "--max-age=%lu", deepen_since);
 773                 if (deepen_not.nr) {
 774                         argv_array_push(&av, "--not");
 775                         for (i = 0; i < deepen_not.nr; i++) {
 776                                 struct string_list_item *s = deepen_not.items + i;
 777                                 argv_array_push(&av, s->string);
 778                         }
 779                         argv_array_push(&av, "--not");
 780                 }
 781                 for (i = 0; i < want_obj.nr; i++) {
 782                         struct object *o = want_obj.objects[i].item;
 783                         argv_array_push(&av, oid_to_hex(&o->oid));
 784                 }
 785                 deepen_by_rev_list(av.argc, av.argv, &shallows);
 786                 argv_array_clear(&av);
 787         }
 788         else
 789                 if (shallows.nr > 0) {
 790                         int i;
 791                         for (i = 0; i < shallows.nr; i++)
 792                                 register_shallow(shallows.objects[i].item->oid.hash);
 793                 }
 794
 795         shallow_nr += shallows.nr;
 796         free(shallows.objects);
 797 }
 798
 799 /* return non-zero if the ref is hidden, otherwise 0 */
 800 static int mark_our_ref(const char *refname, const char *refname_full,
 801                         const struct object_id *oid)
 802 {
 803         struct object *o = lookup_unknown_object(oid->hash);
 804
 805         if (ref_is_hidden(refname, refname_full)) {
 806                 o->flags |= HIDDEN_REF;
 807                 return 1;
 808         }
 809         o->flags |= OUR_REF;
 810         return 0;
 811 }
 812
 813 static int check_ref(const char *refname_full, const struct object_id *oid,
 814                      int flag, void *cb_data)
 815 {
 816         const char *refname = strip_namespace(refname_full);
 817
 818         mark_our_ref(refname, refname_full, oid);
 819         return 0;
 820 }
 821
 822 static void format_symref_info(struct strbuf *buf, struct string_list *symref)
 823 {
 824         struct string_list_item *item;
 825
 826         if (!symref->nr)
 827                 return;
 828         for_each_string_list_item(item, symref)
 829                 strbuf_addf(buf, " symref=%s:%s", item->string, (char *)item->util);
 830 }
 831
 832 static int send_ref(const char *refname, const struct object_id *oid,
 833                     int flag, void *cb_data)
 834 {
 835         static const char *capabilities = "multi_ack thin-pack side-band"
 836                 " side-band-64k ofs-delta shallow deepen-since deepen-not no-progress"
 837                 " include-tag multi_ack_detailed";
 838         const char *refname_nons = strip_namespace(refname);
 839         struct object_id peeled;
 840
 841         if (mark_our_ref(refname_nons, refname, oid))
 842                 return 0;
 843
 844         if (capabilities) {
 845                 struct strbuf symref_info = STRBUF_INIT;
 846
 847                 format_symref_info(&symref_info, cb_data);
 848                 packet_write(1, "%s %s%c%s%s%s%s%s agent=%s\n",
 849                              oid_to_hex(oid), refname_nons,
 850                              0, capabilities,
 851                              (allow_unadvertised_object_request & ALLOW_TIP_SHA1) ?
 852                                      " allow-tip-sha1-in-want" : "",
 853                              (allow_unadvertised_object_request & ALLOW_REACHABLE_SHA1) ?
 854                                      " allow-reachable-sha1-in-want" : "",
 855                              stateless_rpc ? " no-done" : "",
 856                              symref_info.buf,
 857                              git_user_agent_sanitized());
 858                 strbuf_release(&symref_info);
 859         } else {
 860                 packet_write(1, "%s %s\n", oid_to_hex(oid), refname_nons);
 861         }
 862         capabilities = NULL;
 863         if (!peel_ref(refname, peeled.hash))
 864                 packet_write(1, "%s %s^{}\n", oid_to_hex(&peeled), refname_nons);
 865         return 0;
 866 }
 867
 868 static int find_symref(const char *refname, const struct object_id *oid,
 869                        int flag, void *cb_data)
 870 {
 871         const char *symref_target;
 872         struct string_list_item *item;
 873         struct object_id unused;
 874
 875         if ((flag & REF_ISSYMREF) == 0)
 876                 return 0;
 877         symref_target = resolve_ref_unsafe(refname, 0, unused.hash, &flag);
 878         if (!symref_target || (flag & REF_ISSYMREF) == 0)
 879                 die("'%s' is a symref but it is not?", refname);
 880         item = string_list_append(cb_data, refname);
 881         item->util = xstrdup(symref_target);
 882         return 0;
 883 }
 884
 885 static void upload_pack(void)
 886 {
 887         struct string_list symref = STRING_LIST_INIT_DUP;
 888
 889         head_ref_namespaced(find_symref, &symref);
 890
 891         if (advertise_refs || !stateless_rpc) {
 892                 reset_timeout();
 893                 head_ref_namespaced(send_ref, &symref);
 894                 for_each_namespaced_ref(send_ref, &symref);
 895                 advertise_shallow_grafts(1);
 896                 packet_flush(1);
 897         } else {
 898                 head_ref_namespaced(check_ref, NULL);
 899                 for_each_namespaced_ref(check_ref, NULL);
 900         }
 901         string_list_clear(&symref, 1);
 902         if (advertise_refs)
 903                 return;
 904
 905         receive_needs();
 906         if (want_obj.nr) {
 907                 get_common_commits();
 908                 create_pack_file();
 909         }
 910 }
 911
 912 static int upload_pack_config(const char *var, const char *value, void *unused)
 913 {
 914         if (!strcmp("uploadpack.allowtipsha1inwant", var)) {
 915                 if (git_config_bool(var, value))
 916                         allow_unadvertised_object_request |= ALLOW_TIP_SHA1;
 917                 else
 918                         allow_unadvertised_object_request &= ~ALLOW_TIP_SHA1;
 919         } else if (!strcmp("uploadpack.allowreachablesha1inwant", var)) {
 920                 if (git_config_bool(var, value))
 921                         allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
 922                 else
 923                         allow_unadvertised_object_request &= ~ALLOW_REACHABLE_SHA1;
 924         } else if (!strcmp("uploadpack.keepalive", var)) {
 925                 keepalive = git_config_int(var, value);
 926                 if (!keepalive)
 927                         keepalive = -1;
 928         }
 929         return parse_hide_refs_config(var, value, "uploadpack");
 930 }
 931
 932 int main(int argc, char **argv)
 933 {
 934         char *dir;
 935         int i;
 936         int strict = 0;
 937
 938         git_setup_gettext();
 939
 940         packet_trace_identity("upload-pack");
 941         git_extract_argv0_path(argv[0]);
 942         check_replace_refs = 0;
 943
 944         for (i = 1; i < argc; i++) {
 945                 const char *arg = argv[i];
 946
 947                 if (arg[0] != '-')
 948                         break;
 949                 if (!strcmp(arg, "--advertise-refs")) {
 950                         advertise_refs = 1;
 951                         continue;
 952                 }
 953                 if (!strcmp(arg, "--stateless-rpc")) {
 954                         stateless_rpc = 1;
 955                         continue;
 956                 }
 957                 if (!strcmp(arg, "--strict")) {
 958                         strict = 1;
 959                         continue;
 960                 }
 961                 if (skip_prefix(arg, "--timeout=", &arg)) {
 962                         timeout = atoi(arg);
 963                         daemon_mode = 1;
 964                         continue;
 965                 }
 966                 if (!strcmp(arg, "--")) {
 967                         i++;
 968                         break;
 969                 }
 970         }
 971
 972         if (i != argc-1)
 973                 usage(upload_pack_usage);
 974
 975         setup_path();
 976
 977         dir = argv[i];
 978
 979         if (!enter_repo(dir, strict))
 980                 die("'%s' does not appear to be a git repository", dir);
 981
 982         git_config(upload_pack_config, NULL);
 983         upload_pack();
 984         return 0;
 985 }