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 #include "argv-array.h"
  19 #include "prio-queue.h"
  20
  21 static const char * const upload_pack_usage[] = {
  22         N_("git upload-pack [<options>] <dir>"),
  23         NULL
  24 };
  25
  26 /* Remember to update object flag allocation in object.h */
  27 #define THEY_HAVE       (1u << 11)
  28 #define OUR_REF         (1u << 12)
  29 #define WANTED          (1u << 13)
  30 #define COMMON_KNOWN    (1u << 14)
  31 #define REACHABLE       (1u << 15)
  32
  33 #define SHALLOW         (1u << 16)
  34 #define NOT_SHALLOW     (1u << 17)
  35 #define CLIENT_SHALLOW  (1u << 18)
  36 #define HIDDEN_REF      (1u << 19)
  37
  38 static unsigned long oldest_have;
  39
  40 static int deepen_relative;
  41 static int multi_ack;
  42 static int no_done;
  43 static int use_thin_pack, use_ofs_delta, use_include_tag;
  44 static int no_progress, daemon_mode;
  45 /* Allow specifying sha1 if it is a ref tip. */
  46 #define ALLOW_TIP_SHA1  01
  47 /* Allow request of a sha1 if it is reachable from a ref (possibly hidden ref). */
  48 #define ALLOW_REACHABLE_SHA1    02
  49 static unsigned int allow_unadvertised_object_request;
  50 static int shallow_nr;
  51 static struct object_array have_obj;
  52 static struct object_array want_obj;
  53 static struct object_array extra_edge_obj;
  54 static unsigned int timeout;
  55 static int keepalive = 5;
  56 /* 0 for no sideband,
  57  * otherwise maximum packet size (up to 65520 bytes).
  58  */
  59 static int use_sideband;
  60 static int advertise_refs;
  61 static int stateless_rpc;
  62 static const char *pack_objects_hook;
  63
  64 static void reset_timeout(void)
  65 {
  66         alarm(timeout);
  67 }
  68
  69 static void send_client_data(int fd, const char *data, ssize_t sz)
  70 {
  71         if (use_sideband) {
  72                 send_sideband(1, fd, data, sz, use_sideband);
  73                 return;
  74         }
  75         if (fd == 3)
  76                 /* emergency quit */
  77                 fd = 2;
  78         if (fd == 2) {
  79                 /* XXX: are we happy to lose stuff here? */
  80                 xwrite(fd, data, sz);
  81                 return;
  82         }
  83         write_or_die(fd, data, sz);
  84 }
  85
  86 static int write_one_shallow(const struct commit_graft *graft, void *cb_data)
  87 {
  88         FILE *fp = cb_data;
  89         if (graft->nr_parent == -1)
  90                 fprintf(fp, "--shallow %s\n", oid_to_hex(&graft->oid));
  91         return 0;
  92 }
  93
  94 static void create_pack_file(void)
  95 {
  96         struct child_process pack_objects = CHILD_PROCESS_INIT;
  97         char data[8193], progress[128];
  98         char abort_msg[] = "aborting due to possible repository "
  99                 "corruption on the remote side.";
 100         int buffered = -1;
 101         ssize_t sz;
 102         int i;
 103         FILE *pipe_fd;
 104
 105         if (!pack_objects_hook)
 106                 pack_objects.git_cmd = 1;
 107         else {
 108                 argv_array_push(&pack_objects.args, pack_objects_hook);
 109                 argv_array_push(&pack_objects.args, "git");
 110                 pack_objects.use_shell = 1;
 111         }
 112
 113         if (shallow_nr) {
 114                 argv_array_push(&pack_objects.args, "--shallow-file");
 115                 argv_array_push(&pack_objects.args, "");
 116         }
 117         argv_array_push(&pack_objects.args, "pack-objects");
 118         argv_array_push(&pack_objects.args, "--revs");
 119         if (use_thin_pack)
 120                 argv_array_push(&pack_objects.args, "--thin");
 121
 122         argv_array_push(&pack_objects.args, "--stdout");
 123         if (shallow_nr)
 124                 argv_array_push(&pack_objects.args, "--shallow");
 125         if (!no_progress)
 126                 argv_array_push(&pack_objects.args, "--progress");
 127         if (use_ofs_delta)
 128                 argv_array_push(&pack_objects.args, "--delta-base-offset");
 129         if (use_include_tag)
 130                 argv_array_push(&pack_objects.args, "--include-tag");
 131
 132         pack_objects.in = -1;
 133         pack_objects.out = -1;
 134         pack_objects.err = -1;
 135
 136         if (start_command(&pack_objects))
 137                 die("git upload-pack: unable to fork git-pack-objects");
 138
 139         pipe_fd = xfdopen(pack_objects.in, "w");
 140
 141         if (shallow_nr)
 142                 for_each_commit_graft(write_one_shallow, pipe_fd);
 143
 144         for (i = 0; i < want_obj.nr; i++)
 145                 fprintf(pipe_fd, "%s\n",
 146                         oid_to_hex(&want_obj.objects[i].item->oid));
 147         fprintf(pipe_fd, "--not\n");
 148         for (i = 0; i < have_obj.nr; i++)
 149                 fprintf(pipe_fd, "%s\n",
 150                         oid_to_hex(&have_obj.objects[i].item->oid));
 151         for (i = 0; i < extra_edge_obj.nr; i++)
 152                 fprintf(pipe_fd, "%s\n",
 153                         oid_to_hex(&extra_edge_obj.objects[i].item->oid));
 154         fprintf(pipe_fd, "\n");
 155         fflush(pipe_fd);
 156         fclose(pipe_fd);
 157
 158         /* We read from pack_objects.err to capture stderr output for
 159          * progress bar, and pack_objects.out to capture the pack data.
 160          */
 161
 162         while (1) {
 163                 struct pollfd pfd[2];
 164                 int pe, pu, pollsize;
 165                 int ret;
 166
 167                 reset_timeout();
 168
 169                 pollsize = 0;
 170                 pe = pu = -1;
 171
 172                 if (0 <= pack_objects.out) {
 173                         pfd[pollsize].fd = pack_objects.out;
 174                         pfd[pollsize].events = POLLIN;
 175                         pu = pollsize;
 176                         pollsize++;
 177                 }
 178                 if (0 <= pack_objects.err) {
 179                         pfd[pollsize].fd = pack_objects.err;
 180                         pfd[pollsize].events = POLLIN;
 181                         pe = pollsize;
 182                         pollsize++;
 183                 }
 184
 185                 if (!pollsize)
 186                         break;
 187
 188                 ret = poll(pfd, pollsize,
 189                         keepalive < 0 ? -1 : 1000 * keepalive);
 190
 191                 if (ret < 0) {
 192                         if (errno != EINTR) {
 193                                 error_errno("poll failed, resuming");
 194                                 sleep(1);
 195                         }
 196                         continue;
 197                 }
 198                 if (0 <= pe && (pfd[pe].revents & (POLLIN|POLLHUP))) {
 199                         /* Status ready; we ship that in the side-band
 200                          * or dump to the standard error.
 201                          */
 202                         sz = xread(pack_objects.err, progress,
 203                                   sizeof(progress));
 204                         if (0 < sz)
 205                                 send_client_data(2, progress, sz);
 206                         else if (sz == 0) {
 207                                 close(pack_objects.err);
 208                                 pack_objects.err = -1;
 209                         }
 210                         else
 211                                 goto fail;
 212                         /* give priority to status messages */
 213                         continue;
 214                 }
 215                 if (0 <= pu && (pfd[pu].revents & (POLLIN|POLLHUP))) {
 216                         /* Data ready; we keep the last byte to ourselves
 217                          * in case we detect broken rev-list, so that we
 218                          * can leave the stream corrupted.  This is
 219                          * unfortunate -- unpack-objects would happily
 220                          * accept a valid packdata with trailing garbage,
 221                          * so appending garbage after we pass all the
 222                          * pack data is not good enough to signal
 223                          * breakage to downstream.
 224                          */
 225                         char *cp = data;
 226                         ssize_t outsz = 0;
 227                         if (0 <= buffered) {
 228                                 *cp++ = buffered;
 229                                 outsz++;
 230                         }
 231                         sz = xread(pack_objects.out, cp,
 232                                   sizeof(data) - outsz);
 233                         if (0 < sz)
 234                                 ;
 235                         else if (sz == 0) {
 236                                 close(pack_objects.out);
 237                                 pack_objects.out = -1;
 238                         }
 239                         else
 240                                 goto fail;
 241                         sz += outsz;
 242                         if (1 < sz) {
 243                                 buffered = data[sz-1] & 0xFF;
 244                                 sz--;
 245                         }
 246                         else
 247                                 buffered = -1;
 248                         send_client_data(1, data, sz);
 249                 }
 250
 251                 /*
 252                  * We hit the keepalive timeout without saying anything; send
 253                  * an empty message on the data sideband just to let the other
 254                  * side know we're still working on it, but don't have any data
 255                  * yet.
 256                  *
 257                  * If we don't have a sideband channel, there's no room in the
 258                  * protocol to say anything, so those clients are just out of
 259                  * luck.
 260                  */
 261                 if (!ret && use_sideband) {
 262                         static const char buf[] = "0005\1";
 263                         write_or_die(1, buf, 5);
 264                 }
 265         }
 266
 267         if (finish_command(&pack_objects)) {
 268                 error("git upload-pack: git-pack-objects died with error.");
 269                 goto fail;
 270         }
 271
 272         /* flush the data */
 273         if (0 <= buffered) {
 274                 data[0] = buffered;
 275                 send_client_data(1, data, 1);
 276                 fprintf(stderr, "flushed.\n");
 277         }
 278         if (use_sideband)
 279                 packet_flush(1);
 280         return;
 281
 282  fail:
 283         send_client_data(3, abort_msg, sizeof(abort_msg));
 284         die("git upload-pack: %s", abort_msg);
 285 }
 286
 287 static int got_sha1(const char *hex, unsigned char *sha1)
 288 {
 289         struct object *o;
 290         int we_knew_they_have = 0;
 291
 292         if (get_sha1_hex(hex, sha1))
 293                 die("git upload-pack: expected SHA1 object, got '%s'", hex);
 294         if (!has_sha1_file(sha1))
 295                 return -1;
 296
 297         o = parse_object(sha1);
 298         if (!o)
 299                 die("oops (%s)", sha1_to_hex(sha1));
 300         if (o->type == OBJ_COMMIT) {
 301                 struct commit_list *parents;
 302                 struct commit *commit = (struct commit *)o;
 303                 if (o->flags & THEY_HAVE)
 304                         we_knew_they_have = 1;
 305                 else
 306                         o->flags |= THEY_HAVE;
 307                 if (!oldest_have || (commit->date < oldest_have))
 308                         oldest_have = commit->date;
 309                 for (parents = commit->parents;
 310                      parents;
 311                      parents = parents->next)
 312                         parents->item->object.flags |= THEY_HAVE;
 313         }
 314         if (!we_knew_they_have) {
 315                 add_object_array(o, NULL, &have_obj);
 316                 return 1;
 317         }
 318         return 0;
 319 }
 320
 321 static int reachable(struct commit *want)
 322 {
 323         struct prio_queue work = { compare_commits_by_commit_date };
 324
 325         prio_queue_put(&work, want);
 326         while (work.nr) {
 327                 struct commit_list *list;
 328                 struct commit *commit = prio_queue_get(&work);
 329
 330                 if (commit->object.flags & THEY_HAVE) {
 331                         want->object.flags |= COMMON_KNOWN;
 332                         break;
 333                 }
 334                 if (!commit->object.parsed)
 335                         parse_object(commit->object.oid.hash);
 336                 if (commit->object.flags & REACHABLE)
 337                         continue;
 338                 commit->object.flags |= REACHABLE;
 339                 if (commit->date < oldest_have)
 340                         continue;
 341                 for (list = commit->parents; list; list = list->next) {
 342                         struct commit *parent = list->item;
 343                         if (!(parent->object.flags & REACHABLE))
 344                                 prio_queue_put(&work, parent);
 345                 }
 346         }
 347         want->object.flags |= REACHABLE;
 348         clear_commit_marks(want, REACHABLE);
 349         clear_prio_queue(&work);
 350         return (want->object.flags & COMMON_KNOWN);
 351 }
 352
 353 static int ok_to_give_up(void)
 354 {
 355         int i;
 356
 357         if (!have_obj.nr)
 358                 return 0;
 359
 360         for (i = 0; i < want_obj.nr; i++) {
 361                 struct object *want = want_obj.objects[i].item;
 362
 363                 if (want->flags & COMMON_KNOWN)
 364                         continue;
 365                 want = deref_tag(want, "a want line", 0);
 366                 if (!want || want->type != OBJ_COMMIT) {
 367                         /* no way to tell if this is reachable by
 368                          * looking at the ancestry chain alone, so
 369                          * leave a note to ourselves not to worry about
 370                          * this object anymore.
 371                          */
 372                         want_obj.objects[i].item->flags |= COMMON_KNOWN;
 373                         continue;
 374                 }
 375                 if (!reachable((struct commit *)want))
 376                         return 0;
 377         }
 378         return 1;
 379 }
 380
 381 static int get_common_commits(void)
 382 {
 383         unsigned char sha1[20];
 384         char last_hex[41];
 385         int got_common = 0;
 386         int got_other = 0;
 387         int sent_ready = 0;
 388
 389         save_commit_buffer = 0;
 390
 391         for (;;) {
 392                 char *line = packet_read_line(0, NULL);
 393                 const char *arg;
 394
 395                 reset_timeout();
 396
 397                 if (!line) {
 398                         if (multi_ack == 2 && got_common
 399                             && !got_other && ok_to_give_up()) {
 400                                 sent_ready = 1;
 401                                 packet_write(1, "ACK %s ready\n", last_hex);
 402                         }
 403                         if (have_obj.nr == 0 || multi_ack)
 404                                 packet_write(1, "NAK\n");
 405
 406                         if (no_done && sent_ready) {
 407                                 packet_write(1, "ACK %s\n", last_hex);
 408                                 return 0;
 409                         }
 410                         if (stateless_rpc)
 411                                 exit(0);
 412                         got_common = 0;
 413                         got_other = 0;
 414                         continue;
 415                 }
 416                 if (skip_prefix(line, "have ", &arg)) {
 417                         switch (got_sha1(arg, sha1)) {
 418                         case -1: /* they have what we do not */
 419                                 got_other = 1;
 420                                 if (multi_ack && ok_to_give_up()) {
 421                                         const char *hex = sha1_to_hex(sha1);
 422                                         if (multi_ack == 2) {
 423                                                 sent_ready = 1;
 424                                                 packet_write(1, "ACK %s ready\n", hex);
 425                                         } else
 426                                                 packet_write(1, "ACK %s continue\n", hex);
 427                                 }
 428                                 break;
 429                         default:
 430                                 got_common = 1;
 431                                 memcpy(last_hex, sha1_to_hex(sha1), 41);
 432                                 if (multi_ack == 2)
 433                                         packet_write(1, "ACK %s common\n", last_hex);
 434                                 else if (multi_ack)
 435                                         packet_write(1, "ACK %s continue\n", last_hex);
 436                                 else if (have_obj.nr == 1)
 437                                         packet_write(1, "ACK %s\n", last_hex);
 438                                 break;
 439                         }
 440                         continue;
 441                 }
 442                 if (!strcmp(line, "done")) {
 443                         if (have_obj.nr > 0) {
 444                                 if (multi_ack)
 445                                         packet_write(1, "ACK %s\n", last_hex);
 446                                 return 0;
 447                         }
 448                         packet_write(1, "NAK\n");
 449                         return -1;
 450                 }
 451                 die("git upload-pack: expected SHA1 list, got '%s'", line);
 452         }
 453 }
 454
 455 static int is_our_ref(struct object *o)
 456 {
 457         int allow_hidden_ref = (allow_unadvertised_object_request &
 458                         (ALLOW_TIP_SHA1 | ALLOW_REACHABLE_SHA1));
 459         return o->flags & ((allow_hidden_ref ? HIDDEN_REF : 0) | OUR_REF);
 460 }
 461
 462 /*
 463  * on successful case, it's up to the caller to close cmd->out
 464  */
 465 static int do_reachable_revlist(struct child_process *cmd,
 466                                 struct object_array *src,
 467                                 struct object_array *reachable)
 468 {
 469         static const char *argv[] = {
 470                 "rev-list", "--stdin", NULL,
 471         };
 472         struct object *o;
 473         char namebuf[42]; /* ^ + SHA-1 + LF */
 474         int i;
 475
 476         cmd->argv = argv;
 477         cmd->git_cmd = 1;
 478         cmd->no_stderr = 1;
 479         cmd->in = -1;
 480         cmd->out = -1;
 481
 482         /*
 483          * If the next rev-list --stdin encounters an unknown commit,
 484          * it terminates, which will cause SIGPIPE in the write loop
 485          * below.
 486          */
 487         sigchain_push(SIGPIPE, SIG_IGN);
 488
 489         if (start_command(cmd))
 490                 goto error;
 491
 492         namebuf[0] = '^';
 493         namebuf[41] = '\n';
 494         for (i = get_max_object_index(); 0 < i; ) {
 495                 o = get_indexed_object(--i);
 496                 if (!o)
 497                         continue;
 498                 if (reachable && o->type == OBJ_COMMIT)
 499                         o->flags &= ~TMP_MARK;
 500                 if (!is_our_ref(o))
 501                         continue;
 502                 memcpy(namebuf + 1, oid_to_hex(&o->oid), GIT_SHA1_HEXSZ);
 503                 if (write_in_full(cmd->in, namebuf, 42) < 0)
 504                         goto error;
 505         }
 506         namebuf[40] = '\n';
 507         for (i = 0; i < src->nr; i++) {
 508                 o = src->objects[i].item;
 509                 if (is_our_ref(o)) {
 510                         if (reachable)
 511                                 add_object_array(o, NULL, reachable);
 512                         continue;
 513                 }
 514                 if (reachable && o->type == OBJ_COMMIT)
 515                         o->flags |= TMP_MARK;
 516                 memcpy(namebuf, oid_to_hex(&o->oid), GIT_SHA1_HEXSZ);
 517                 if (write_in_full(cmd->in, namebuf, 41) < 0)
 518                         goto error;
 519         }
 520         close(cmd->in);
 521         cmd->in = -1;
 522         sigchain_pop(SIGPIPE);
 523
 524         return 0;
 525
 526 error:
 527         sigchain_pop(SIGPIPE);
 528
 529         if (cmd->in >= 0)
 530                 close(cmd->in);
 531         if (cmd->out >= 0)
 532                 close(cmd->out);
 533         return -1;
 534 }
 535
 536 static int get_reachable_list(struct object_array *src,
 537                               struct object_array *reachable)
 538 {
 539         struct child_process cmd = CHILD_PROCESS_INIT;
 540         int i;
 541         struct object *o;
 542         char namebuf[42]; /* ^ + SHA-1 + LF */
 543
 544         if (do_reachable_revlist(&cmd, src, reachable) < 0)
 545                 return -1;
 546
 547         while ((i = read_in_full(cmd.out, namebuf, 41)) == 41) {
 548                 struct object_id sha1;
 549
 550                 if (namebuf[40] != '\n' || get_oid_hex(namebuf, &sha1))
 551                         break;
 552
 553                 o = lookup_object(sha1.hash);
 554                 if (o && o->type == OBJ_COMMIT) {
 555                         o->flags &= ~TMP_MARK;
 556                 }
 557         }
 558         for (i = get_max_object_index(); 0 < i; i--) {
 559                 o = get_indexed_object(i - 1);
 560                 if (o && o->type == OBJ_COMMIT &&
 561                     (o->flags & TMP_MARK)) {
 562                         add_object_array(o, NULL, reachable);
 563                                 o->flags &= ~TMP_MARK;
 564                 }
 565         }
 566         close(cmd.out);
 567
 568         if (finish_command(&cmd))
 569                 return -1;
 570
 571         return 0;
 572 }
 573
 574 static int has_unreachable(struct object_array *src)
 575 {
 576         struct child_process cmd = CHILD_PROCESS_INIT;
 577         char buf[1];
 578         int i;
 579
 580         if (do_reachable_revlist(&cmd, src, NULL) < 0)
 581                 return 1;
 582
 583         /*
 584          * The commits out of the rev-list are not ancestors of
 585          * our ref.
 586          */
 587         i = read_in_full(cmd.out, buf, 1);
 588         if (i)
 589                 goto error;
 590         close(cmd.out);
 591         cmd.out = -1;
 592
 593         /*
 594          * rev-list may have died by encountering a bad commit
 595          * in the history, in which case we do want to bail out
 596          * even when it showed no commit.
 597          */
 598         if (finish_command(&cmd))
 599                 goto error;
 600
 601         /* All the non-tip ones are ancestors of what we advertised */
 602         return 0;
 603
 604 error:
 605         sigchain_pop(SIGPIPE);
 606         if (cmd.out >= 0)
 607                 close(cmd.out);
 608         return 1;
 609 }
 610
 611 static void check_non_tip(void)
 612 {
 613         int i;
 614
 615         /*
 616          * In the normal in-process case without
 617          * uploadpack.allowReachableSHA1InWant,
 618          * non-tip requests can never happen.
 619          */
 620         if (!stateless_rpc && !(allow_unadvertised_object_request & ALLOW_REACHABLE_SHA1))
 621                 goto error;
 622         if (!has_unreachable(&want_obj))
 623                 /* All the non-tip ones are ancestors of what we advertised */
 624                 return;
 625
 626 error:
 627         /* Pick one of them (we know there at least is one) */
 628         for (i = 0; i < want_obj.nr; i++) {
 629                 struct object *o = want_obj.objects[i].item;
 630                 if (!is_our_ref(o))
 631                         die("git upload-pack: not our ref %s",
 632                             oid_to_hex(&o->oid));
 633         }
 634 }
 635
 636 static void send_shallow(struct commit_list *result)
 637 {
 638         while (result) {
 639                 struct object *object = &result->item->object;
 640                 if (!(object->flags & (CLIENT_SHALLOW|NOT_SHALLOW))) {
 641                         packet_write(1, "shallow %s",
 642                                      oid_to_hex(&object->oid));
 643                         register_shallow(object->oid.hash);
 644                         shallow_nr++;
 645                 }
 646                 result = result->next;
 647         }
 648 }
 649
 650 static void send_unshallow(const struct object_array *shallows)
 651 {
 652         int i;
 653
 654         for (i = 0; i < shallows->nr; i++) {
 655                 struct object *object = shallows->objects[i].item;
 656                 if (object->flags & NOT_SHALLOW) {
 657                         struct commit_list *parents;
 658                         packet_write(1, "unshallow %s",
 659                                      oid_to_hex(&object->oid));
 660                         object->flags &= ~CLIENT_SHALLOW;
 661                         /*
 662                          * We want to _register_ "object" as shallow, but we
 663                          * also need to traverse object's parents to deepen a
 664                          * shallow clone. Unregister it for now so we can
 665                          * parse and add the parents to the want list, then
 666                          * re-register it.
 667                          */
 668                         unregister_shallow(object->oid.hash);
 669                         object->parsed = 0;
 670                         parse_commit_or_die((struct commit *)object);
 671                         parents = ((struct commit *)object)->parents;
 672                         while (parents) {
 673                                 add_object_array(&parents->item->object,
 674                                                  NULL, &want_obj);
 675                                 parents = parents->next;
 676                         }
 677                         add_object_array(object, NULL, &extra_edge_obj);
 678                 }
 679                 /* make sure commit traversal conforms to client */
 680                 register_shallow(object->oid.hash);
 681         }
 682 }
 683
 684 static void deepen(int depth, int deepen_relative,
 685                    struct object_array *shallows)
 686 {
 687         if (depth == INFINITE_DEPTH && !is_repository_shallow()) {
 688                 int i;
 689
 690                 for (i = 0; i < shallows->nr; i++) {
 691                         struct object *object = shallows->objects[i].item;
 692                         object->flags |= NOT_SHALLOW;
 693                 }
 694         } else if (deepen_relative) {
 695                 struct object_array reachable_shallows = OBJECT_ARRAY_INIT;
 696                 struct commit_list *result;
 697
 698                 get_reachable_list(shallows, &reachable_shallows);
 699                 result = get_shallow_commits(&reachable_shallows,
 700                                              depth + 1,
 701                                              SHALLOW, NOT_SHALLOW);
 702                 send_shallow(result);
 703                 free_commit_list(result);
 704                 object_array_clear(&reachable_shallows);
 705         } else {
 706                 struct commit_list *result;
 707
 708                 result = get_shallow_commits(&want_obj, depth,
 709                                              SHALLOW, NOT_SHALLOW);
 710                 send_shallow(result);
 711                 free_commit_list(result);
 712         }
 713
 714         send_unshallow(shallows);
 715         packet_flush(1);
 716 }
 717
 718 static void deepen_by_rev_list(int ac, const char **av,
 719                                struct object_array *shallows)
 720 {
 721         struct commit_list *result;
 722
 723         result = get_shallow_commits_by_rev_list(ac, av, SHALLOW, NOT_SHALLOW);
 724         send_shallow(result);
 725         free_commit_list(result);
 726         send_unshallow(shallows);
 727         packet_flush(1);
 728 }
 729
 730 static void receive_needs(void)
 731 {
 732         struct object_array shallows = OBJECT_ARRAY_INIT;
 733         struct string_list deepen_not = STRING_LIST_INIT_DUP;
 734         int depth = 0;
 735         int has_non_tip = 0;
 736         unsigned long deepen_since = 0;
 737         int deepen_rev_list = 0;
 738
 739         shallow_nr = 0;
 740         for (;;) {
 741                 struct object *o;
 742                 const char *features;
 743                 unsigned char sha1_buf[20];
 744                 char *line = packet_read_line(0, NULL);
 745                 const char *arg;
 746
 747                 reset_timeout();
 748                 if (!line)
 749                         break;
 750
 751                 if (skip_prefix(line, "shallow ", &arg)) {
 752                         unsigned char sha1[20];
 753                         struct object *object;
 754                         if (get_sha1_hex(arg, sha1))
 755                                 die("invalid shallow line: %s", line);
 756                         object = parse_object(sha1);
 757                         if (!object)
 758                                 continue;
 759                         if (object->type != OBJ_COMMIT)
 760                                 die("invalid shallow object %s", sha1_to_hex(sha1));
 761                         if (!(object->flags & CLIENT_SHALLOW)) {
 762                                 object->flags |= CLIENT_SHALLOW;
 763                                 add_object_array(object, NULL, &shallows);
 764                         }
 765                         continue;
 766                 }
 767                 if (skip_prefix(line, "deepen ", &arg)) {
 768                         char *end = NULL;
 769                         depth = strtol(arg, &end, 0);
 770                         if (!end || *end || depth <= 0)
 771                                 die("Invalid deepen: %s", line);
 772                         continue;
 773                 }
 774                 if (skip_prefix(line, "deepen-since ", &arg)) {
 775                         char *end = NULL;
 776                         deepen_since = strtoul(arg, &end, 0);
 777                         if (!end || *end || !deepen_since ||
 778                             /* revisions.c's max_age -1 is special */
 779                             deepen_since == -1)
 780                                 die("Invalid deepen-since: %s", line);
 781                         deepen_rev_list = 1;
 782                         continue;
 783                 }
 784                 if (skip_prefix(line, "deepen-not ", &arg)) {
 785                         char *ref = NULL;
 786                         unsigned char sha1[20];
 787                         if (expand_ref(arg, strlen(arg), sha1, &ref) != 1)
 788                                 die("git upload-pack: ambiguous deepen-not: %s", line);
 789                         string_list_append(&deepen_not, ref);
 790                         free(ref);
 791                         deepen_rev_list = 1;
 792                         continue;
 793                 }
 794                 if (!skip_prefix(line, "want ", &arg) ||
 795                     get_sha1_hex(arg, sha1_buf))
 796                         die("git upload-pack: protocol error, "
 797                             "expected to get sha, not '%s'", line);
 798
 799                 features = arg + 40;
 800
 801                 if (parse_feature_request(features, "deepen-relative"))
 802                         deepen_relative = 1;
 803                 if (parse_feature_request(features, "multi_ack_detailed"))
 804                         multi_ack = 2;
 805                 else if (parse_feature_request(features, "multi_ack"))
 806                         multi_ack = 1;
 807                 if (parse_feature_request(features, "no-done"))
 808                         no_done = 1;
 809                 if (parse_feature_request(features, "thin-pack"))
 810                         use_thin_pack = 1;
 811                 if (parse_feature_request(features, "ofs-delta"))
 812                         use_ofs_delta = 1;
 813                 if (parse_feature_request(features, "side-band-64k"))
 814                         use_sideband = LARGE_PACKET_MAX;
 815                 else if (parse_feature_request(features, "side-band"))
 816                         use_sideband = DEFAULT_PACKET_MAX;
 817                 if (parse_feature_request(features, "no-progress"))
 818                         no_progress = 1;
 819                 if (parse_feature_request(features, "include-tag"))
 820                         use_include_tag = 1;
 821
 822                 o = parse_object(sha1_buf);
 823                 if (!o)
 824                         die("git upload-pack: not our ref %s",
 825                             sha1_to_hex(sha1_buf));
 826                 if (!(o->flags & WANTED)) {
 827                         o->flags |= WANTED;
 828                         if (!is_our_ref(o))
 829                                 has_non_tip = 1;
 830                         add_object_array(o, NULL, &want_obj);
 831                 }
 832         }
 833
 834         /*
 835          * We have sent all our refs already, and the other end
 836          * should have chosen out of them. When we are operating
 837          * in the stateless RPC mode, however, their choice may
 838          * have been based on the set of older refs advertised
 839          * by another process that handled the initial request.
 840          */
 841         if (has_non_tip)
 842                 check_non_tip();
 843
 844         if (!use_sideband && daemon_mode)
 845                 no_progress = 1;
 846
 847         if (depth == 0 && !deepen_rev_list && shallows.nr == 0)
 848                 return;
 849         if (depth > 0 && deepen_rev_list)
 850                 die("git upload-pack: deepen and deepen-since (or deepen-not) cannot be used together");
 851         if (depth > 0)
 852                 deepen(depth, deepen_relative, &shallows);
 853         else if (deepen_rev_list) {
 854                 struct argv_array av = ARGV_ARRAY_INIT;
 855                 int i;
 856
 857                 argv_array_push(&av, "rev-list");
 858                 if (deepen_since)
 859                         argv_array_pushf(&av, "--max-age=%lu", deepen_since);
 860                 if (deepen_not.nr) {
 861                         argv_array_push(&av, "--not");
 862                         for (i = 0; i < deepen_not.nr; i++) {
 863                                 struct string_list_item *s = deepen_not.items + i;
 864                                 argv_array_push(&av, s->string);
 865                         }
 866                         argv_array_push(&av, "--not");
 867                 }
 868                 for (i = 0; i < want_obj.nr; i++) {
 869                         struct object *o = want_obj.objects[i].item;
 870                         argv_array_push(&av, oid_to_hex(&o->oid));
 871                 }
 872                 deepen_by_rev_list(av.argc, av.argv, &shallows);
 873                 argv_array_clear(&av);
 874         }
 875         else
 876                 if (shallows.nr > 0) {
 877                         int i;
 878                         for (i = 0; i < shallows.nr; i++)
 879                                 register_shallow(shallows.objects[i].item->oid.hash);
 880                 }
 881
 882         shallow_nr += shallows.nr;
 883         free(shallows.objects);
 884 }
 885
 886 /* return non-zero if the ref is hidden, otherwise 0 */
 887 static int mark_our_ref(const char *refname, const char *refname_full,
 888                         const struct object_id *oid)
 889 {
 890         struct object *o = lookup_unknown_object(oid->hash);
 891
 892         if (ref_is_hidden(refname, refname_full)) {
 893                 o->flags |= HIDDEN_REF;
 894                 return 1;
 895         }
 896         o->flags |= OUR_REF;
 897         return 0;
 898 }
 899
 900 static int check_ref(const char *refname_full, const struct object_id *oid,
 901                      int flag, void *cb_data)
 902 {
 903         const char *refname = strip_namespace(refname_full);
 904
 905         mark_our_ref(refname, refname_full, oid);
 906         return 0;
 907 }
 908
 909 static void format_symref_info(struct strbuf *buf, struct string_list *symref)
 910 {
 911         struct string_list_item *item;
 912
 913         if (!symref->nr)
 914                 return;
 915         for_each_string_list_item(item, symref)
 916                 strbuf_addf(buf, " symref=%s:%s", item->string, (char *)item->util);
 917 }
 918
 919 static int send_ref(const char *refname, const struct object_id *oid,
 920                     int flag, void *cb_data)
 921 {
 922         static const char *capabilities = "multi_ack thin-pack side-band"
 923                 " side-band-64k ofs-delta shallow deepen-since deepen-not"
 924                 " deepen-relative no-progress include-tag multi_ack_detailed";
 925         const char *refname_nons = strip_namespace(refname);
 926         struct object_id peeled;
 927
 928         if (mark_our_ref(refname_nons, refname, oid))
 929                 return 0;
 930
 931         if (capabilities) {
 932                 struct strbuf symref_info = STRBUF_INIT;
 933
 934                 format_symref_info(&symref_info, cb_data);
 935                 packet_write(1, "%s %s%c%s%s%s%s%s agent=%s\n",
 936                              oid_to_hex(oid), refname_nons,
 937                              0, capabilities,
 938                              (allow_unadvertised_object_request & ALLOW_TIP_SHA1) ?
 939                                      " allow-tip-sha1-in-want" : "",
 940                              (allow_unadvertised_object_request & ALLOW_REACHABLE_SHA1) ?
 941                                      " allow-reachable-sha1-in-want" : "",
 942                              stateless_rpc ? " no-done" : "",
 943                              symref_info.buf,
 944                              git_user_agent_sanitized());
 945                 strbuf_release(&symref_info);
 946         } else {
 947                 packet_write(1, "%s %s\n", oid_to_hex(oid), refname_nons);
 948         }
 949         capabilities = NULL;
 950         if (!peel_ref(refname, peeled.hash))
 951                 packet_write(1, "%s %s^{}\n", oid_to_hex(&peeled), refname_nons);
 952         return 0;
 953 }
 954
 955 static int find_symref(const char *refname, const struct object_id *oid,
 956                        int flag, void *cb_data)
 957 {
 958         const char *symref_target;
 959         struct string_list_item *item;
 960         struct object_id unused;
 961
 962         if ((flag & REF_ISSYMREF) == 0)
 963                 return 0;
 964         symref_target = resolve_ref_unsafe(refname, 0, unused.hash, &flag);
 965         if (!symref_target || (flag & REF_ISSYMREF) == 0)
 966                 die("'%s' is a symref but it is not?", refname);
 967         item = string_list_append(cb_data, refname);
 968         item->util = xstrdup(symref_target);
 969         return 0;
 970 }
 971
 972 static void upload_pack(void)
 973 {
 974         struct string_list symref = STRING_LIST_INIT_DUP;
 975
 976         head_ref_namespaced(find_symref, &symref);
 977
 978         if (advertise_refs || !stateless_rpc) {
 979                 reset_timeout();
 980                 head_ref_namespaced(send_ref, &symref);
 981                 for_each_namespaced_ref(send_ref, &symref);
 982                 advertise_shallow_grafts(1);
 983                 packet_flush(1);
 984         } else {
 985                 head_ref_namespaced(check_ref, NULL);
 986                 for_each_namespaced_ref(check_ref, NULL);
 987         }
 988         string_list_clear(&symref, 1);
 989         if (advertise_refs)
 990                 return;
 991
 992         receive_needs();
 993         if (want_obj.nr) {
 994                 get_common_commits();
 995                 create_pack_file();
 996         }
 997 }
 998
 999 static int upload_pack_config(const char *var, const char *value, void *unused)
1000 {
1001         if (!strcmp("uploadpack.allowtipsha1inwant", var)) {
1002                 if (git_config_bool(var, value))
1003                         allow_unadvertised_object_request |= ALLOW_TIP_SHA1;
1004                 else
1005                         allow_unadvertised_object_request &= ~ALLOW_TIP_SHA1;
1006         } else if (!strcmp("uploadpack.allowreachablesha1inwant", var)) {
1007                 if (git_config_bool(var, value))
1008                         allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
1009                 else
1010                         allow_unadvertised_object_request &= ~ALLOW_REACHABLE_SHA1;
1011         } else if (!strcmp("uploadpack.keepalive", var)) {
1012                 keepalive = git_config_int(var, value);
1013                 if (!keepalive)
1014                         keepalive = -1;
1015         } else if (current_config_scope() != CONFIG_SCOPE_REPO) {
1016                 if (!strcmp("uploadpack.packobjectshook", var))
1017                         return git_config_string(&pack_objects_hook, var, value);
1018         }
1019         return parse_hide_refs_config(var, value, "uploadpack");
1020 }
1021
1022 int cmd_main(int argc, const char **argv)
1023 {
1024         const char *dir;
1025         int strict = 0;
1026         struct option options[] = {
1027                 OPT_BOOL(0, "stateless-rpc", &stateless_rpc,
1028                          N_("quit after a single request/response exchange")),
1029                 OPT_BOOL(0, "advertise-refs", &advertise_refs,
1030                          N_("exit immediately after initial ref advertisement")),
1031                 OPT_BOOL(0, "strict", &strict,
1032                          N_("do not try <directory>/.git/ if <directory> is no Git directory")),
1033                 OPT_INTEGER(0, "timeout", &timeout,
1034                             N_("interrupt transfer after <n> seconds of inactivity")),
1035                 OPT_END()
1036         };
1037
1038         packet_trace_identity("upload-pack");
1039         check_replace_refs = 0;
1040
1041         argc = parse_options(argc, argv, NULL, options, upload_pack_usage, 0);
1042
1043         if (argc != 1)
1044                 usage_with_options(upload_pack_usage, options);
1045
1046         if (timeout)
1047                 daemon_mode = 1;
1048
1049         setup_path();
1050
1051         dir = argv[0];
1052
1053         if (!enter_repo(dir, strict))
1054                 die("'%s' does not appear to be a git repository", dir);
1055
1056         git_config(upload_pack_config, NULL);
1057         upload_pack();
1058         return 0;
1059 }