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 "sigchain.h"
  14
  15 static const char upload_pack_usage[] = "git upload-pack [--strict] [--timeout=<n>] <dir>";
  16
  17 /* bits #0..7 in revision.h, #8..10 in commit.c */
  18 #define THEY_HAVE       (1u << 11)
  19 #define OUR_REF         (1u << 12)
  20 #define WANTED          (1u << 13)
  21 #define COMMON_KNOWN    (1u << 14)
  22 #define REACHABLE       (1u << 15)
  23
  24 #define SHALLOW         (1u << 16)
  25 #define NOT_SHALLOW     (1u << 17)
  26 #define CLIENT_SHALLOW  (1u << 18)
  27
  28 static unsigned long oldest_have;
  29
  30 static int multi_ack, nr_our_refs;
  31 static int no_done;
  32 static int use_thin_pack, use_ofs_delta, use_include_tag;
  33 static int no_progress, daemon_mode;
  34 static int shallow_nr;
  35 static struct object_array have_obj;
  36 static struct object_array want_obj;
  37 static struct object_array extra_edge_obj;
  38 static unsigned int timeout;
  39 /* 0 for no sideband,
  40  * otherwise maximum packet size (up to 65520 bytes).
  41  */
  42 static int use_sideband;
  43 static int debug_fd;
  44 static int advertise_refs;
  45 static int stateless_rpc;
  46
  47 static void reset_timeout(void)
  48 {
  49         alarm(timeout);
  50 }
  51
  52 static int strip(char *line, int len)
  53 {
  54         if (len && line[len-1] == '\n')
  55                 line[--len] = 0;
  56         return len;
  57 }
  58
  59 static ssize_t send_client_data(int fd, const char *data, ssize_t sz)
  60 {
  61         if (use_sideband)
  62                 return send_sideband(1, fd, data, sz, use_sideband);
  63         if (fd == 3)
  64                 /* emergency quit */
  65                 fd = 2;
  66         if (fd == 2) {
  67                 /* XXX: are we happy to lose stuff here? */
  68                 xwrite(fd, data, sz);
  69                 return sz;
  70         }
  71         return safe_write(fd, data, sz);
  72 }
  73
  74 static FILE *pack_pipe = NULL;
  75 static void show_commit(struct commit *commit, void *data)
  76 {
  77         if (commit->object.flags & BOUNDARY)
  78                 fputc('-', pack_pipe);
  79         if (fputs(sha1_to_hex(commit->object.sha1), pack_pipe) < 0)
  80                 die("broken output pipe");
  81         fputc('\n', pack_pipe);
  82         fflush(pack_pipe);
  83         free(commit->buffer);
  84         commit->buffer = NULL;
  85 }
  86
  87 static void show_object(struct object *obj, const struct name_path *path, const char *component)
  88 {
  89         /* An object with name "foo\n0000000..." can be used to
  90          * confuse downstream git-pack-objects very badly.
  91          */
  92         const char *name = path_name(path, component);
  93         const char *ep = strchr(name, '\n');
  94         if (ep) {
  95                 fprintf(pack_pipe, "%s %.*s\n", sha1_to_hex(obj->sha1),
  96                        (int) (ep - name),
  97                        name);
  98         }
  99         else
 100                 fprintf(pack_pipe, "%s %s\n",
 101                                 sha1_to_hex(obj->sha1), name);
 102         free((char *)name);
 103 }
 104
 105 static void show_edge(struct commit *commit)
 106 {
 107         fprintf(pack_pipe, "-%s\n", sha1_to_hex(commit->object.sha1));
 108 }
 109
 110 static int do_rev_list(int in, int out, void *user_data)
 111 {
 112         int i;
 113         struct rev_info revs;
 114
 115         pack_pipe = xfdopen(out, "w");
 116         init_revisions(&revs, NULL);
 117         revs.tag_objects = 1;
 118         revs.tree_objects = 1;
 119         revs.blob_objects = 1;
 120         if (use_thin_pack)
 121                 revs.edge_hint = 1;
 122
 123         for (i = 0; i < want_obj.nr; i++) {
 124                 struct object *o = want_obj.objects[i].item;
 125                 /* why??? */
 126                 o->flags &= ~UNINTERESTING;
 127                 add_pending_object(&revs, o, NULL);
 128         }
 129         for (i = 0; i < have_obj.nr; i++) {
 130                 struct object *o = have_obj.objects[i].item;
 131                 o->flags |= UNINTERESTING;
 132                 add_pending_object(&revs, o, NULL);
 133         }
 134         setup_revisions(0, NULL, &revs, NULL);
 135         if (prepare_revision_walk(&revs))
 136                 die("revision walk setup failed");
 137         mark_edges_uninteresting(revs.commits, &revs, show_edge);
 138         if (use_thin_pack)
 139                 for (i = 0; i < extra_edge_obj.nr; i++)
 140                         fprintf(pack_pipe, "-%s\n", sha1_to_hex(
 141                                         extra_edge_obj.objects[i].item->sha1));
 142         traverse_commit_list(&revs, show_commit, show_object, NULL);
 143         fflush(pack_pipe);
 144         fclose(pack_pipe);
 145         return 0;
 146 }
 147
 148 static void create_pack_file(void)
 149 {
 150         struct async rev_list;
 151         struct child_process pack_objects;
 152         int create_full_pack = (nr_our_refs == want_obj.nr && !have_obj.nr);
 153         char data[8193], progress[128];
 154         char abort_msg[] = "aborting due to possible repository "
 155                 "corruption on the remote side.";
 156         int buffered = -1;
 157         ssize_t sz;
 158         const char *argv[10];
 159         int arg = 0;
 160
 161         argv[arg++] = "pack-objects";
 162         if (!shallow_nr) {
 163                 argv[arg++] = "--revs";
 164                 if (create_full_pack)
 165                         argv[arg++] = "--all";
 166                 else if (use_thin_pack)
 167                         argv[arg++] = "--thin";
 168         }
 169
 170         argv[arg++] = "--stdout";
 171         if (!no_progress)
 172                 argv[arg++] = "--progress";
 173         if (use_ofs_delta)
 174                 argv[arg++] = "--delta-base-offset";
 175         if (use_include_tag)
 176                 argv[arg++] = "--include-tag";
 177         argv[arg++] = NULL;
 178
 179         memset(&pack_objects, 0, sizeof(pack_objects));
 180         pack_objects.in = -1;
 181         pack_objects.out = -1;
 182         pack_objects.err = -1;
 183         pack_objects.git_cmd = 1;
 184         pack_objects.argv = argv;
 185
 186         if (start_command(&pack_objects))
 187                 die("git upload-pack: unable to fork git-pack-objects");
 188
 189         if (shallow_nr) {
 190                 memset(&rev_list, 0, sizeof(rev_list));
 191                 rev_list.proc = do_rev_list;
 192                 rev_list.out = pack_objects.in;
 193                 if (start_async(&rev_list))
 194                         die("git upload-pack: unable to fork git-rev-list");
 195         }
 196         else {
 197                 FILE *pipe_fd = xfdopen(pack_objects.in, "w");
 198                 if (!create_full_pack) {
 199                         int i;
 200                         for (i = 0; i < want_obj.nr; i++)
 201                                 fprintf(pipe_fd, "%s\n", sha1_to_hex(want_obj.objects[i].item->sha1));
 202                         fprintf(pipe_fd, "--not\n");
 203                         for (i = 0; i < have_obj.nr; i++)
 204                                 fprintf(pipe_fd, "%s\n", sha1_to_hex(have_obj.objects[i].item->sha1));
 205                 }
 206
 207                 fprintf(pipe_fd, "\n");
 208                 fflush(pipe_fd);
 209                 fclose(pipe_fd);
 210         }
 211
 212
 213         /* We read from pack_objects.err to capture stderr output for
 214          * progress bar, and pack_objects.out to capture the pack data.
 215          */
 216
 217         while (1) {
 218                 struct pollfd pfd[2];
 219                 int pe, pu, pollsize;
 220
 221                 reset_timeout();
 222
 223                 pollsize = 0;
 224                 pe = pu = -1;
 225
 226                 if (0 <= pack_objects.out) {
 227                         pfd[pollsize].fd = pack_objects.out;
 228                         pfd[pollsize].events = POLLIN;
 229                         pu = pollsize;
 230                         pollsize++;
 231                 }
 232                 if (0 <= pack_objects.err) {
 233                         pfd[pollsize].fd = pack_objects.err;
 234                         pfd[pollsize].events = POLLIN;
 235                         pe = pollsize;
 236                         pollsize++;
 237                 }
 238
 239                 if (!pollsize)
 240                         break;
 241
 242                 if (poll(pfd, pollsize, -1) < 0) {
 243                         if (errno != EINTR) {
 244                                 error("poll failed, resuming: %s",
 245                                       strerror(errno));
 246                                 sleep(1);
 247                         }
 248                         continue;
 249                 }
 250                 if (0 <= pe && (pfd[pe].revents & (POLLIN|POLLHUP))) {
 251                         /* Status ready; we ship that in the side-band
 252                          * or dump to the standard error.
 253                          */
 254                         sz = xread(pack_objects.err, progress,
 255                                   sizeof(progress));
 256                         if (0 < sz)
 257                                 send_client_data(2, progress, sz);
 258                         else if (sz == 0) {
 259                                 close(pack_objects.err);
 260                                 pack_objects.err = -1;
 261                         }
 262                         else
 263                                 goto fail;
 264                         /* give priority to status messages */
 265                         continue;
 266                 }
 267                 if (0 <= pu && (pfd[pu].revents & (POLLIN|POLLHUP))) {
 268                         /* Data ready; we keep the last byte to ourselves
 269                          * in case we detect broken rev-list, so that we
 270                          * can leave the stream corrupted.  This is
 271                          * unfortunate -- unpack-objects would happily
 272                          * accept a valid packdata with trailing garbage,
 273                          * so appending garbage after we pass all the
 274                          * pack data is not good enough to signal
 275                          * breakage to downstream.
 276                          */
 277                         char *cp = data;
 278                         ssize_t outsz = 0;
 279                         if (0 <= buffered) {
 280                                 *cp++ = buffered;
 281                                 outsz++;
 282                         }
 283                         sz = xread(pack_objects.out, cp,
 284                                   sizeof(data) - outsz);
 285                         if (0 < sz)
 286                                 ;
 287                         else if (sz == 0) {
 288                                 close(pack_objects.out);
 289                                 pack_objects.out = -1;
 290                         }
 291                         else
 292                                 goto fail;
 293                         sz += outsz;
 294                         if (1 < sz) {
 295                                 buffered = data[sz-1] & 0xFF;
 296                                 sz--;
 297                         }
 298                         else
 299                                 buffered = -1;
 300                         sz = send_client_data(1, data, sz);
 301                         if (sz < 0)
 302                                 goto fail;
 303                 }
 304         }
 305
 306         if (finish_command(&pack_objects)) {
 307                 error("git upload-pack: git-pack-objects died with error.");
 308                 goto fail;
 309         }
 310         if (shallow_nr && finish_async(&rev_list))
 311                 goto fail;      /* error was already reported */
 312
 313         /* flush the data */
 314         if (0 <= buffered) {
 315                 data[0] = buffered;
 316                 sz = send_client_data(1, data, 1);
 317                 if (sz < 0)
 318                         goto fail;
 319                 fprintf(stderr, "flushed.\n");
 320         }
 321         if (use_sideband)
 322                 packet_flush(1);
 323         return;
 324
 325  fail:
 326         send_client_data(3, abort_msg, sizeof(abort_msg));
 327         die("git upload-pack: %s", abort_msg);
 328 }
 329
 330 static int got_sha1(char *hex, unsigned char *sha1)
 331 {
 332         struct object *o;
 333         int we_knew_they_have = 0;
 334
 335         if (get_sha1_hex(hex, sha1))
 336                 die("git upload-pack: expected SHA1 object, got '%s'", hex);
 337         if (!has_sha1_file(sha1))
 338                 return -1;
 339
 340         o = lookup_object(sha1);
 341         if (!(o && o->parsed))
 342                 o = parse_object(sha1);
 343         if (!o)
 344                 die("oops (%s)", sha1_to_hex(sha1));
 345         if (o->type == OBJ_COMMIT) {
 346                 struct commit_list *parents;
 347                 struct commit *commit = (struct commit *)o;
 348                 if (o->flags & THEY_HAVE)
 349                         we_knew_they_have = 1;
 350                 else
 351                         o->flags |= THEY_HAVE;
 352                 if (!oldest_have || (commit->date < oldest_have))
 353                         oldest_have = commit->date;
 354                 for (parents = commit->parents;
 355                      parents;
 356                      parents = parents->next)
 357                         parents->item->object.flags |= THEY_HAVE;
 358         }
 359         if (!we_knew_they_have) {
 360                 add_object_array(o, NULL, &have_obj);
 361                 return 1;
 362         }
 363         return 0;
 364 }
 365
 366 static int reachable(struct commit *want)
 367 {
 368         struct commit_list *work = NULL;
 369
 370         commit_list_insert_by_date(want, &work);
 371         while (work) {
 372                 struct commit_list *list = work->next;
 373                 struct commit *commit = work->item;
 374                 free(work);
 375                 work = list;
 376
 377                 if (commit->object.flags & THEY_HAVE) {
 378                         want->object.flags |= COMMON_KNOWN;
 379                         break;
 380                 }
 381                 if (!commit->object.parsed)
 382                         parse_object(commit->object.sha1);
 383                 if (commit->object.flags & REACHABLE)
 384                         continue;
 385                 commit->object.flags |= REACHABLE;
 386                 if (commit->date < oldest_have)
 387                         continue;
 388                 for (list = commit->parents; list; list = list->next) {
 389                         struct commit *parent = list->item;
 390                         if (!(parent->object.flags & REACHABLE))
 391                                 commit_list_insert_by_date(parent, &work);
 392                 }
 393         }
 394         want->object.flags |= REACHABLE;
 395         clear_commit_marks(want, REACHABLE);
 396         free_commit_list(work);
 397         return (want->object.flags & COMMON_KNOWN);
 398 }
 399
 400 static int ok_to_give_up(void)
 401 {
 402         int i;
 403
 404         if (!have_obj.nr)
 405                 return 0;
 406
 407         for (i = 0; i < want_obj.nr; i++) {
 408                 struct object *want = want_obj.objects[i].item;
 409
 410                 if (want->flags & COMMON_KNOWN)
 411                         continue;
 412                 want = deref_tag(want, "a want line", 0);
 413                 if (!want || want->type != OBJ_COMMIT) {
 414                         /* no way to tell if this is reachable by
 415                          * looking at the ancestry chain alone, so
 416                          * leave a note to ourselves not to worry about
 417                          * this object anymore.
 418                          */
 419                         want_obj.objects[i].item->flags |= COMMON_KNOWN;
 420                         continue;
 421                 }
 422                 if (!reachable((struct commit *)want))
 423                         return 0;
 424         }
 425         return 1;
 426 }
 427
 428 static int get_common_commits(void)
 429 {
 430         static char line[1000];
 431         unsigned char sha1[20];
 432         char last_hex[41];
 433         int got_common = 0;
 434         int got_other = 0;
 435         int sent_ready = 0;
 436
 437         save_commit_buffer = 0;
 438
 439         for (;;) {
 440                 int len = packet_read_line(0, line, sizeof(line));
 441                 reset_timeout();
 442
 443                 if (!len) {
 444                         if (multi_ack == 2 && got_common
 445                             && !got_other && ok_to_give_up()) {
 446                                 sent_ready = 1;
 447                                 packet_write(1, "ACK %s ready\n", last_hex);
 448                         }
 449                         if (have_obj.nr == 0 || multi_ack)
 450                                 packet_write(1, "NAK\n");
 451
 452                         if (no_done && sent_ready) {
 453                                 packet_write(1, "ACK %s\n", last_hex);
 454                                 return 0;
 455                         }
 456                         if (stateless_rpc)
 457                                 exit(0);
 458                         got_common = 0;
 459                         got_other = 0;
 460                         continue;
 461                 }
 462                 strip(line, len);
 463                 if (!prefixcmp(line, "have ")) {
 464                         switch (got_sha1(line+5, sha1)) {
 465                         case -1: /* they have what we do not */
 466                                 got_other = 1;
 467                                 if (multi_ack && ok_to_give_up()) {
 468                                         const char *hex = sha1_to_hex(sha1);
 469                                         if (multi_ack == 2) {
 470                                                 sent_ready = 1;
 471                                                 packet_write(1, "ACK %s ready\n", hex);
 472                                         } else
 473                                                 packet_write(1, "ACK %s continue\n", hex);
 474                                 }
 475                                 break;
 476                         default:
 477                                 got_common = 1;
 478                                 memcpy(last_hex, sha1_to_hex(sha1), 41);
 479                                 if (multi_ack == 2)
 480                                         packet_write(1, "ACK %s common\n", last_hex);
 481                                 else if (multi_ack)
 482                                         packet_write(1, "ACK %s continue\n", last_hex);
 483                                 else if (have_obj.nr == 1)
 484                                         packet_write(1, "ACK %s\n", last_hex);
 485                                 break;
 486                         }
 487                         continue;
 488                 }
 489                 if (!strcmp(line, "done")) {
 490                         if (have_obj.nr > 0) {
 491                                 if (multi_ack)
 492                                         packet_write(1, "ACK %s\n", last_hex);
 493                                 return 0;
 494                         }
 495                         packet_write(1, "NAK\n");
 496                         return -1;
 497                 }
 498                 die("git upload-pack: expected SHA1 list, got '%s'", line);
 499         }
 500 }
 501
 502 static void check_non_tip(void)
 503 {
 504         static const char *argv[] = {
 505                 "rev-list", "--stdin", NULL,
 506         };
 507         static struct child_process cmd;
 508         struct object *o;
 509         char namebuf[42]; /* ^ + SHA-1 + LF */
 510         int i;
 511
 512         /* In the normal in-process case non-tip request can never happen */
 513         if (!stateless_rpc)
 514                 goto error;
 515
 516         cmd.argv = argv;
 517         cmd.git_cmd = 1;
 518         cmd.no_stderr = 1;
 519         cmd.in = -1;
 520         cmd.out = -1;
 521
 522         if (start_command(&cmd))
 523                 goto error;
 524
 525         /*
 526          * If rev-list --stdin encounters an unknown commit, it
 527          * terminates, which will cause SIGPIPE in the write loop
 528          * below.
 529          */
 530         sigchain_push(SIGPIPE, SIG_IGN);
 531
 532         namebuf[0] = '^';
 533         namebuf[41] = '\n';
 534         for (i = get_max_object_index(); 0 < i; ) {
 535                 o = get_indexed_object(--i);
 536                 if (!o)
 537                         continue;
 538                 if (!(o->flags & OUR_REF))
 539                         continue;
 540                 memcpy(namebuf + 1, sha1_to_hex(o->sha1), 40);
 541                 if (write_in_full(cmd.in, namebuf, 42) < 0)
 542                         goto error;
 543         }
 544         namebuf[40] = '\n';
 545         for (i = 0; i < want_obj.nr; i++) {
 546                 o = want_obj.objects[i].item;
 547                 if (o->flags & OUR_REF)
 548                         continue;
 549                 memcpy(namebuf, sha1_to_hex(o->sha1), 40);
 550                 if (write_in_full(cmd.in, namebuf, 41) < 0)
 551                         goto error;
 552         }
 553         close(cmd.in);
 554
 555         sigchain_pop(SIGPIPE);
 556
 557         /*
 558          * The commits out of the rev-list are not ancestors of
 559          * our ref.
 560          */
 561         i = read_in_full(cmd.out, namebuf, 1);
 562         if (i)
 563                 goto error;
 564         close(cmd.out);
 565
 566         /*
 567          * rev-list may have died by encountering a bad commit
 568          * in the history, in which case we do want to bail out
 569          * even when it showed no commit.
 570          */
 571         if (finish_command(&cmd))
 572                 goto error;
 573
 574         /* All the non-tip ones are ancestors of what we advertised */
 575         return;
 576
 577 error:
 578         /* Pick one of them (we know there at least is one) */
 579         for (i = 0; i < want_obj.nr; i++) {
 580                 o = want_obj.objects[i].item;
 581                 if (!(o->flags & OUR_REF))
 582                         die("git upload-pack: not our ref %s",
 583                             sha1_to_hex(o->sha1));
 584         }
 585 }
 586
 587 static void receive_needs(void)
 588 {
 589         struct object_array shallows = OBJECT_ARRAY_INIT;
 590         static char line[1000];
 591         int len, depth = 0;
 592         int has_non_tip = 0;
 593
 594         shallow_nr = 0;
 595         if (debug_fd)
 596                 write_str_in_full(debug_fd, "#S\n");
 597         for (;;) {
 598                 struct object *o;
 599                 unsigned char sha1_buf[20];
 600                 len = packet_read_line(0, line, sizeof(line));
 601                 reset_timeout();
 602                 if (!len)
 603                         break;
 604                 if (debug_fd)
 605                         write_in_full(debug_fd, line, len);
 606
 607                 if (!prefixcmp(line, "shallow ")) {
 608                         unsigned char sha1[20];
 609                         struct object *object;
 610                         if (get_sha1(line + 8, sha1))
 611                                 die("invalid shallow line: %s", line);
 612                         object = parse_object(sha1);
 613                         if (!object)
 614                                 die("did not find object for %s", line);
 615                         object->flags |= CLIENT_SHALLOW;
 616                         add_object_array(object, NULL, &shallows);
 617                         continue;
 618                 }
 619                 if (!prefixcmp(line, "deepen ")) {
 620                         char *end;
 621                         depth = strtol(line + 7, &end, 0);
 622                         if (end == line + 7 || depth <= 0)
 623                                 die("Invalid deepen: %s", line);
 624                         continue;
 625                 }
 626                 if (prefixcmp(line, "want ") ||
 627                     get_sha1_hex(line+5, sha1_buf))
 628                         die("git upload-pack: protocol error, "
 629                             "expected to get sha, not '%s'", line);
 630                 if (strstr(line+45, "multi_ack_detailed"))
 631                         multi_ack = 2;
 632                 else if (strstr(line+45, "multi_ack"))
 633                         multi_ack = 1;
 634                 if (strstr(line+45, "no-done"))
 635                         no_done = 1;
 636                 if (strstr(line+45, "thin-pack"))
 637                         use_thin_pack = 1;
 638                 if (strstr(line+45, "ofs-delta"))
 639                         use_ofs_delta = 1;
 640                 if (strstr(line+45, "side-band-64k"))
 641                         use_sideband = LARGE_PACKET_MAX;
 642                 else if (strstr(line+45, "side-band"))
 643                         use_sideband = DEFAULT_PACKET_MAX;
 644                 if (strstr(line+45, "no-progress"))
 645                         no_progress = 1;
 646                 if (strstr(line+45, "include-tag"))
 647                         use_include_tag = 1;
 648
 649                 o = lookup_object(sha1_buf);
 650                 if (!o)
 651                         die("git upload-pack: not our ref %s",
 652                             sha1_to_hex(sha1_buf));
 653                 if (!(o->flags & WANTED)) {
 654                         o->flags |= WANTED;
 655                         if (!(o->flags & OUR_REF))
 656                                 has_non_tip = 1;
 657                         add_object_array(o, NULL, &want_obj);
 658                 }
 659         }
 660         if (debug_fd)
 661                 write_str_in_full(debug_fd, "#E\n");
 662
 663         /*
 664          * We have sent all our refs already, and the other end
 665          * should have chosen out of them. When we are operating
 666          * in the stateless RPC mode, however, their choice may
 667          * have been based on the set of older refs advertised
 668          * by another process that handled the initial request.
 669          */
 670         if (has_non_tip)
 671                 check_non_tip();
 672
 673         if (!use_sideband && daemon_mode)
 674                 no_progress = 1;
 675
 676         if (depth == 0 && shallows.nr == 0)
 677                 return;
 678         if (depth > 0) {
 679                 struct commit_list *result, *backup;
 680                 int i;
 681                 backup = result = get_shallow_commits(&want_obj, depth,
 682                         SHALLOW, NOT_SHALLOW);
 683                 while (result) {
 684                         struct object *object = &result->item->object;
 685                         if (!(object->flags & (CLIENT_SHALLOW|NOT_SHALLOW))) {
 686                                 packet_write(1, "shallow %s",
 687                                                 sha1_to_hex(object->sha1));
 688                                 register_shallow(object->sha1);
 689                                 shallow_nr++;
 690                         }
 691                         result = result->next;
 692                 }
 693                 free_commit_list(backup);
 694                 for (i = 0; i < shallows.nr; i++) {
 695                         struct object *object = shallows.objects[i].item;
 696                         if (object->flags & NOT_SHALLOW) {
 697                                 struct commit_list *parents;
 698                                 packet_write(1, "unshallow %s",
 699                                         sha1_to_hex(object->sha1));
 700                                 object->flags &= ~CLIENT_SHALLOW;
 701                                 /* make sure the real parents are parsed */
 702                                 unregister_shallow(object->sha1);
 703                                 object->parsed = 0;
 704                                 if (parse_commit((struct commit *)object))
 705                                         die("invalid commit");
 706                                 parents = ((struct commit *)object)->parents;
 707                                 while (parents) {
 708                                         add_object_array(&parents->item->object,
 709                                                         NULL, &want_obj);
 710                                         parents = parents->next;
 711                                 }
 712                                 add_object_array(object, NULL, &extra_edge_obj);
 713                         }
 714                         /* make sure commit traversal conforms to client */
 715                         register_shallow(object->sha1);
 716                 }
 717                 packet_flush(1);
 718         } else
 719                 if (shallows.nr > 0) {
 720                         int i;
 721                         for (i = 0; i < shallows.nr; i++)
 722                                 register_shallow(shallows.objects[i].item->sha1);
 723                 }
 724
 725         shallow_nr += shallows.nr;
 726         free(shallows.objects);
 727 }
 728
 729 static int send_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 730 {
 731         static const char *capabilities = "multi_ack thin-pack side-band"
 732                 " side-band-64k ofs-delta shallow no-progress"
 733                 " include-tag multi_ack_detailed";
 734         struct object *o = parse_object(sha1);
 735
 736         if (!o)
 737                 die("git upload-pack: cannot find object %s:", sha1_to_hex(sha1));
 738
 739         if (capabilities)
 740                 packet_write(1, "%s %s%c%s%s\n", sha1_to_hex(sha1), refname,
 741                              0, capabilities,
 742                              stateless_rpc ? " no-done" : "");
 743         else
 744                 packet_write(1, "%s %s\n", sha1_to_hex(sha1), refname);
 745         capabilities = NULL;
 746         if (!(o->flags & OUR_REF)) {
 747                 o->flags |= OUR_REF;
 748                 nr_our_refs++;
 749         }
 750         if (o->type == OBJ_TAG) {
 751                 o = deref_tag(o, refname, 0);
 752                 if (o)
 753                         packet_write(1, "%s %s^{}\n", sha1_to_hex(o->sha1), refname);
 754         }
 755         return 0;
 756 }
 757
 758 static int mark_our_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 759 {
 760         struct object *o = parse_object(sha1);
 761         if (!o)
 762                 die("git upload-pack: cannot find object %s:", sha1_to_hex(sha1));
 763         if (!(o->flags & OUR_REF)) {
 764                 o->flags |= OUR_REF;
 765                 nr_our_refs++;
 766         }
 767         return 0;
 768 }
 769
 770 static void upload_pack(void)
 771 {
 772         if (advertise_refs || !stateless_rpc) {
 773                 reset_timeout();
 774                 head_ref(send_ref, NULL);
 775                 for_each_ref(send_ref, NULL);
 776                 packet_flush(1);
 777         } else {
 778                 head_ref(mark_our_ref, NULL);
 779                 for_each_ref(mark_our_ref, NULL);
 780         }
 781         if (advertise_refs)
 782                 return;
 783
 784         receive_needs();
 785         if (want_obj.nr) {
 786                 get_common_commits();
 787                 create_pack_file();
 788         }
 789 }
 790
 791 int main(int argc, char **argv)
 792 {
 793         char *dir;
 794         int i;
 795         int strict = 0;
 796
 797         packet_trace_identity("upload-pack");
 798         git_extract_argv0_path(argv[0]);
 799         read_replace_refs = 0;
 800
 801         for (i = 1; i < argc; i++) {
 802                 char *arg = argv[i];
 803
 804                 if (arg[0] != '-')
 805                         break;
 806                 if (!strcmp(arg, "--advertise-refs")) {
 807                         advertise_refs = 1;
 808                         continue;
 809                 }
 810                 if (!strcmp(arg, "--stateless-rpc")) {
 811                         stateless_rpc = 1;
 812                         continue;
 813                 }
 814                 if (!strcmp(arg, "--strict")) {
 815                         strict = 1;
 816                         continue;
 817                 }
 818                 if (!prefixcmp(arg, "--timeout=")) {
 819                         timeout = atoi(arg+10);
 820                         daemon_mode = 1;
 821                         continue;
 822                 }
 823                 if (!strcmp(arg, "--")) {
 824                         i++;
 825                         break;
 826                 }
 827         }
 828
 829         if (i != argc-1)
 830                 usage(upload_pack_usage);
 831
 832         setup_path();
 833
 834         dir = argv[i];
 835
 836         if (!enter_repo(dir, strict))
 837                 die("'%s' does not appear to be a git repository", dir);
 838         if (is_repository_shallow())
 839                 die("attempt to fetch/clone from a shallow repository");
 840         if (getenv("GIT_DEBUG_SEND_PACK"))
 841                 debug_fd = atoi(getenv("GIT_DEBUG_SEND_PACK"));
 842         upload_pack();
 843         return 0;
 844 }