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

   1 #include "cache.h"
   2 #include "config.h"
   3 #include "refs.h"
   4 #include "pkt-line.h"
   5 #include "sideband.h"
   6 #include "tag.h"
   7 #include "object.h"
   8 #include "commit.h"
   9 #include "exec_cmd.h"
  10 #include "diff.h"
  11 #include "revision.h"
  12 #include "list-objects.h"
  13 #include "run-command.h"
  14 #include "connect.h"
  15 #include "sigchain.h"
  16 #include "version.h"
  17 #include "string-list.h"
  18 #include "parse-options.h"
  19 #include "argv-array.h"
  20 #include "prio-queue.h"
  21 #include "protocol.h"
  22
  23 static const char * const upload_pack_usage[] = {
  24         N_("git upload-pack [<options>] <dir>"),
  25         NULL
  26 };
  27
  28 /* Remember to update object flag allocation in object.h */
  29 #define THEY_HAVE       (1u << 11)
  30 #define OUR_REF         (1u << 12)
  31 #define WANTED          (1u << 13)
  32 #define COMMON_KNOWN    (1u << 14)
  33 #define REACHABLE       (1u << 15)
  34
  35 #define SHALLOW         (1u << 16)
  36 #define NOT_SHALLOW     (1u << 17)
  37 #define CLIENT_SHALLOW  (1u << 18)
  38 #define HIDDEN_REF      (1u << 19)
  39
  40 static timestamp_t oldest_have;
  41
  42 static int deepen_relative;
  43 static int multi_ack;
  44 static int no_done;
  45 static int use_thin_pack, use_ofs_delta, use_include_tag;
  46 static int no_progress, daemon_mode;
  47 /* Allow specifying sha1 if it is a ref tip. */
  48 #define ALLOW_TIP_SHA1  01
  49 /* Allow request of a sha1 if it is reachable from a ref (possibly hidden ref). */
  50 #define ALLOW_REACHABLE_SHA1    02
  51 /* Allow request of any sha1. Implies ALLOW_TIP_SHA1 and ALLOW_REACHABLE_SHA1. */
  52 #define ALLOW_ANY_SHA1  07
  53 static unsigned int allow_unadvertised_object_request;
  54 static int shallow_nr;
  55 static struct object_array have_obj;
  56 static struct object_array want_obj;
  57 static struct object_array extra_edge_obj;
  58 static unsigned int timeout;
  59 static int keepalive = 5;
  60 /* 0 for no sideband,
  61  * otherwise maximum packet size (up to 65520 bytes).
  62  */
  63 static int use_sideband;
  64 static int advertise_refs;
  65 static int stateless_rpc;
  66 static const char *pack_objects_hook;
  67
  68 static void reset_timeout(void)
  69 {
  70         alarm(timeout);
  71 }
  72
  73 static void send_client_data(int fd, const char *data, ssize_t sz)
  74 {
  75         if (use_sideband) {
  76                 send_sideband(1, fd, data, sz, use_sideband);
  77                 return;
  78         }
  79         if (fd == 3)
  80                 /* emergency quit */
  81                 fd = 2;
  82         if (fd == 2) {
  83                 /* XXX: are we happy to lose stuff here? */
  84                 xwrite(fd, data, sz);
  85                 return;
  86         }
  87         write_or_die(fd, data, sz);
  88 }
  89
  90 static int write_one_shallow(const struct commit_graft *graft, void *cb_data)
  91 {
  92         FILE *fp = cb_data;
  93         if (graft->nr_parent == -1)
  94                 fprintf(fp, "--shallow %s\n", oid_to_hex(&graft->oid));
  95         return 0;
  96 }
  97
  98 static void create_pack_file(void)
  99 {
 100         struct child_process pack_objects = CHILD_PROCESS_INIT;
 101         char data[8193], progress[128];
 102         char abort_msg[] = "aborting due to possible repository "
 103                 "corruption on the remote side.";
 104         int buffered = -1;
 105         ssize_t sz;
 106         int i;
 107         FILE *pipe_fd;
 108
 109         if (!pack_objects_hook)
 110                 pack_objects.git_cmd = 1;
 111         else {
 112                 argv_array_push(&pack_objects.args, pack_objects_hook);
 113                 argv_array_push(&pack_objects.args, "git");
 114                 pack_objects.use_shell = 1;
 115         }
 116
 117         if (shallow_nr) {
 118                 argv_array_push(&pack_objects.args, "--shallow-file");
 119                 argv_array_push(&pack_objects.args, "");
 120         }
 121         argv_array_push(&pack_objects.args, "pack-objects");
 122         argv_array_push(&pack_objects.args, "--revs");
 123         if (use_thin_pack)
 124                 argv_array_push(&pack_objects.args, "--thin");
 125
 126         argv_array_push(&pack_objects.args, "--stdout");
 127         if (shallow_nr)
 128                 argv_array_push(&pack_objects.args, "--shallow");
 129         if (!no_progress)
 130                 argv_array_push(&pack_objects.args, "--progress");
 131         if (use_ofs_delta)
 132                 argv_array_push(&pack_objects.args, "--delta-base-offset");
 133         if (use_include_tag)
 134                 argv_array_push(&pack_objects.args, "--include-tag");
 135
 136         pack_objects.in = -1;
 137         pack_objects.out = -1;
 138         pack_objects.err = -1;
 139
 140         if (start_command(&pack_objects))
 141                 die("git upload-pack: unable to fork git-pack-objects");
 142
 143         pipe_fd = xfdopen(pack_objects.in, "w");
 144
 145         if (shallow_nr)
 146                 for_each_commit_graft(write_one_shallow, pipe_fd);
 147
 148         for (i = 0; i < want_obj.nr; i++)
 149                 fprintf(pipe_fd, "%s\n",
 150                         oid_to_hex(&want_obj.objects[i].item->oid));
 151         fprintf(pipe_fd, "--not\n");
 152         for (i = 0; i < have_obj.nr; i++)
 153                 fprintf(pipe_fd, "%s\n",
 154                         oid_to_hex(&have_obj.objects[i].item->oid));
 155         for (i = 0; i < extra_edge_obj.nr; i++)
 156                 fprintf(pipe_fd, "%s\n",
 157                         oid_to_hex(&extra_edge_obj.objects[i].item->oid));
 158         fprintf(pipe_fd, "\n");
 159         fflush(pipe_fd);
 160         fclose(pipe_fd);
 161
 162         /* We read from pack_objects.err to capture stderr output for
 163          * progress bar, and pack_objects.out to capture the pack data.
 164          */
 165
 166         while (1) {
 167                 struct pollfd pfd[2];
 168                 int pe, pu, pollsize;
 169                 int ret;
 170
 171                 reset_timeout();
 172
 173                 pollsize = 0;
 174                 pe = pu = -1;
 175
 176                 if (0 <= pack_objects.out) {
 177                         pfd[pollsize].fd = pack_objects.out;
 178                         pfd[pollsize].events = POLLIN;
 179                         pu = pollsize;
 180                         pollsize++;
 181                 }
 182                 if (0 <= pack_objects.err) {
 183                         pfd[pollsize].fd = pack_objects.err;
 184                         pfd[pollsize].events = POLLIN;
 185                         pe = pollsize;
 186                         pollsize++;
 187                 }
 188
 189                 if (!pollsize)
 190                         break;
 191
 192                 ret = poll(pfd, pollsize,
 193                         keepalive < 0 ? -1 : 1000 * keepalive);
 194
 195                 if (ret < 0) {
 196                         if (errno != EINTR) {
 197                                 error_errno("poll failed, resuming");
 198                                 sleep(1);
 199                         }
 200                         continue;
 201                 }
 202                 if (0 <= pe && (pfd[pe].revents & (POLLIN|POLLHUP))) {
 203                         /* Status ready; we ship that in the side-band
 204                          * or dump to the standard error.
 205                          */
 206                         sz = xread(pack_objects.err, progress,
 207                                   sizeof(progress));
 208                         if (0 < sz)
 209                                 send_client_data(2, progress, sz);
 210                         else if (sz == 0) {
 211                                 close(pack_objects.err);
 212                                 pack_objects.err = -1;
 213                         }
 214                         else
 215                                 goto fail;
 216                         /* give priority to status messages */
 217                         continue;
 218                 }
 219                 if (0 <= pu && (pfd[pu].revents & (POLLIN|POLLHUP))) {
 220                         /* Data ready; we keep the last byte to ourselves
 221                          * in case we detect broken rev-list, so that we
 222                          * can leave the stream corrupted.  This is
 223                          * unfortunate -- unpack-objects would happily
 224                          * accept a valid packdata with trailing garbage,
 225                          * so appending garbage after we pass all the
 226                          * pack data is not good enough to signal
 227                          * breakage to downstream.
 228                          */
 229                         char *cp = data;
 230                         ssize_t outsz = 0;
 231                         if (0 <= buffered) {
 232                                 *cp++ = buffered;
 233                                 outsz++;
 234                         }
 235                         sz = xread(pack_objects.out, cp,
 236                                   sizeof(data) - outsz);
 237                         if (0 < sz)
 238                                 ;
 239                         else if (sz == 0) {
 240                                 close(pack_objects.out);
 241                                 pack_objects.out = -1;
 242                         }
 243                         else
 244                                 goto fail;
 245                         sz += outsz;
 246                         if (1 < sz) {
 247                                 buffered = data[sz-1] & 0xFF;
 248                                 sz--;
 249                         }
 250                         else
 251                                 buffered = -1;
 252                         send_client_data(1, data, sz);
 253                 }
 254
 255                 /*
 256                  * We hit the keepalive timeout without saying anything; send
 257                  * an empty message on the data sideband just to let the other
 258                  * side know we're still working on it, but don't have any data
 259                  * yet.
 260                  *
 261                  * If we don't have a sideband channel, there's no room in the
 262                  * protocol to say anything, so those clients are just out of
 263                  * luck.
 264                  */
 265                 if (!ret && use_sideband) {
 266                         static const char buf[] = "0005\1";
 267                         write_or_die(1, buf, 5);
 268                 }
 269         }
 270
 271         if (finish_command(&pack_objects)) {
 272                 error("git upload-pack: git-pack-objects died with error.");
 273                 goto fail;
 274         }
 275
 276         /* flush the data */
 277         if (0 <= buffered) {
 278                 data[0] = buffered;
 279                 send_client_data(1, data, 1);
 280                 fprintf(stderr, "flushed.\n");
 281         }
 282         if (use_sideband)
 283                 packet_flush(1);
 284         return;
 285
 286  fail:
 287         send_client_data(3, abort_msg, sizeof(abort_msg));
 288         die("git upload-pack: %s", abort_msg);
 289 }
 290
 291 static int got_oid(const char *hex, struct object_id *oid)
 292 {
 293         struct object *o;
 294         int we_knew_they_have = 0;
 295
 296         if (get_oid_hex(hex, oid))
 297                 die("git upload-pack: expected SHA1 object, got '%s'", hex);
 298         if (!has_object_file(oid))
 299                 return -1;
 300
 301         o = parse_object(oid);
 302         if (!o)
 303                 die("oops (%s)", oid_to_hex(oid));
 304         if (o->type == OBJ_COMMIT) {
 305                 struct commit_list *parents;
 306                 struct commit *commit = (struct commit *)o;
 307                 if (o->flags & THEY_HAVE)
 308                         we_knew_they_have = 1;
 309                 else
 310                         o->flags |= THEY_HAVE;
 311                 if (!oldest_have || (commit->date < oldest_have))
 312                         oldest_have = commit->date;
 313                 for (parents = commit->parents;
 314                      parents;
 315                      parents = parents->next)
 316                         parents->item->object.flags |= THEY_HAVE;
 317         }
 318         if (!we_knew_they_have) {
 319                 add_object_array(o, NULL, &have_obj);
 320                 return 1;
 321         }
 322         return 0;
 323 }
 324
 325 static int reachable(struct commit *want)
 326 {
 327         struct prio_queue work = { compare_commits_by_commit_date };
 328
 329         prio_queue_put(&work, want);
 330         while (work.nr) {
 331                 struct commit_list *list;
 332                 struct commit *commit = prio_queue_get(&work);
 333
 334                 if (commit->object.flags & THEY_HAVE) {
 335                         want->object.flags |= COMMON_KNOWN;
 336                         break;
 337                 }
 338                 if (!commit->object.parsed)
 339                         parse_object(&commit->object.oid);
 340                 if (commit->object.flags & REACHABLE)
 341                         continue;
 342                 commit->object.flags |= REACHABLE;
 343                 if (commit->date < oldest_have)
 344                         continue;
 345                 for (list = commit->parents; list; list = list->next) {
 346                         struct commit *parent = list->item;
 347                         if (!(parent->object.flags & REACHABLE))
 348                                 prio_queue_put(&work, parent);
 349                 }
 350         }
 351         want->object.flags |= REACHABLE;
 352         clear_commit_marks(want, REACHABLE);
 353         clear_prio_queue(&work);
 354         return (want->object.flags & COMMON_KNOWN);
 355 }
 356
 357 static int ok_to_give_up(void)
 358 {
 359         int i;
 360
 361         if (!have_obj.nr)
 362                 return 0;
 363
 364         for (i = 0; i < want_obj.nr; i++) {
 365                 struct object *want = want_obj.objects[i].item;
 366
 367                 if (want->flags & COMMON_KNOWN)
 368                         continue;
 369                 want = deref_tag(want, "a want line", 0);
 370                 if (!want || want->type != OBJ_COMMIT) {
 371                         /* no way to tell if this is reachable by
 372                          * looking at the ancestry chain alone, so
 373                          * leave a note to ourselves not to worry about
 374                          * this object anymore.
 375                          */
 376                         want_obj.objects[i].item->flags |= COMMON_KNOWN;
 377                         continue;
 378                 }
 379                 if (!reachable((struct commit *)want))
 380                         return 0;
 381         }
 382         return 1;
 383 }
 384
 385 static int get_common_commits(void)
 386 {
 387         struct object_id oid;
 388         char last_hex[GIT_MAX_HEXSZ + 1];
 389         int got_common = 0;
 390         int got_other = 0;
 391         int sent_ready = 0;
 392
 393         save_commit_buffer = 0;
 394
 395         for (;;) {
 396                 char *line = packet_read_line(0, NULL);
 397                 const char *arg;
 398
 399                 reset_timeout();
 400
 401                 if (!line) {
 402                         if (multi_ack == 2 && got_common
 403                             && !got_other && ok_to_give_up()) {
 404                                 sent_ready = 1;
 405                                 packet_write_fmt(1, "ACK %s ready\n", last_hex);
 406                         }
 407                         if (have_obj.nr == 0 || multi_ack)
 408                                 packet_write_fmt(1, "NAK\n");
 409
 410                         if (no_done && sent_ready) {
 411                                 packet_write_fmt(1, "ACK %s\n", last_hex);
 412                                 return 0;
 413                         }
 414                         if (stateless_rpc)
 415                                 exit(0);
 416                         got_common = 0;
 417                         got_other = 0;
 418                         continue;
 419                 }
 420                 if (skip_prefix(line, "have ", &arg)) {
 421                         switch (got_oid(arg, &oid)) {
 422                         case -1: /* they have what we do not */
 423                                 got_other = 1;
 424                                 if (multi_ack && ok_to_give_up()) {
 425                                         const char *hex = oid_to_hex(&oid);
 426                                         if (multi_ack == 2) {
 427                                                 sent_ready = 1;
 428                                                 packet_write_fmt(1, "ACK %s ready\n", hex);
 429                                         } else
 430                                                 packet_write_fmt(1, "ACK %s continue\n", hex);
 431                                 }
 432                                 break;
 433                         default:
 434                                 got_common = 1;
 435                                 memcpy(last_hex, oid_to_hex(&oid), 41);
 436                                 if (multi_ack == 2)
 437                                         packet_write_fmt(1, "ACK %s common\n", last_hex);
 438                                 else if (multi_ack)
 439                                         packet_write_fmt(1, "ACK %s continue\n", last_hex);
 440                                 else if (have_obj.nr == 1)
 441                                         packet_write_fmt(1, "ACK %s\n", last_hex);
 442                                 break;
 443                         }
 444                         continue;
 445                 }
 446                 if (!strcmp(line, "done")) {
 447                         if (have_obj.nr > 0) {
 448                                 if (multi_ack)
 449                                         packet_write_fmt(1, "ACK %s\n", last_hex);
 450                                 return 0;
 451                         }
 452                         packet_write_fmt(1, "NAK\n");
 453                         return -1;
 454                 }
 455                 die("git upload-pack: expected SHA1 list, got '%s'", line);
 456         }
 457 }
 458
 459 static int is_our_ref(struct object *o)
 460 {
 461         int allow_hidden_ref = (allow_unadvertised_object_request &
 462                         (ALLOW_TIP_SHA1 | ALLOW_REACHABLE_SHA1));
 463         return o->flags & ((allow_hidden_ref ? HIDDEN_REF : 0) | OUR_REF);
 464 }
 465
 466 /*
 467  * on successful case, it's up to the caller to close cmd->out
 468  */
 469 static int do_reachable_revlist(struct child_process *cmd,
 470                                 struct object_array *src,
 471                                 struct object_array *reachable)
 472 {
 473         static const char *argv[] = {
 474                 "rev-list", "--stdin", NULL,
 475         };
 476         struct object *o;
 477         char namebuf[42]; /* ^ + SHA-1 + LF */
 478         int i;
 479
 480         cmd->argv = argv;
 481         cmd->git_cmd = 1;
 482         cmd->no_stderr = 1;
 483         cmd->in = -1;
 484         cmd->out = -1;
 485
 486         /*
 487          * If the next rev-list --stdin encounters an unknown commit,
 488          * it terminates, which will cause SIGPIPE in the write loop
 489          * below.
 490          */
 491         sigchain_push(SIGPIPE, SIG_IGN);
 492
 493         if (start_command(cmd))
 494                 goto error;
 495
 496         namebuf[0] = '^';
 497         namebuf[GIT_SHA1_HEXSZ + 1] = '\n';
 498         for (i = get_max_object_index(); 0 < i; ) {
 499                 o = get_indexed_object(--i);
 500                 if (!o)
 501                         continue;
 502                 if (reachable && o->type == OBJ_COMMIT)
 503                         o->flags &= ~TMP_MARK;
 504                 if (!is_our_ref(o))
 505                         continue;
 506                 memcpy(namebuf + 1, oid_to_hex(&o->oid), GIT_SHA1_HEXSZ);
 507                 if (write_in_full(cmd->in, namebuf, GIT_SHA1_HEXSZ + 2) < 0)
 508                         goto error;
 509         }
 510         namebuf[GIT_SHA1_HEXSZ] = '\n';
 511         for (i = 0; i < src->nr; i++) {
 512                 o = src->objects[i].item;
 513                 if (is_our_ref(o)) {
 514                         if (reachable)
 515                                 add_object_array(o, NULL, reachable);
 516                         continue;
 517                 }
 518                 if (reachable && o->type == OBJ_COMMIT)
 519                         o->flags |= TMP_MARK;
 520                 memcpy(namebuf, oid_to_hex(&o->oid), GIT_SHA1_HEXSZ);
 521                 if (write_in_full(cmd->in, namebuf, GIT_SHA1_HEXSZ + 1) < 0)
 522                         goto error;
 523         }
 524         close(cmd->in);
 525         cmd->in = -1;
 526         sigchain_pop(SIGPIPE);
 527
 528         return 0;
 529
 530 error:
 531         sigchain_pop(SIGPIPE);
 532
 533         if (cmd->in >= 0)
 534                 close(cmd->in);
 535         if (cmd->out >= 0)
 536                 close(cmd->out);
 537         return -1;
 538 }
 539
 540 static int get_reachable_list(struct object_array *src,
 541                               struct object_array *reachable)
 542 {
 543         struct child_process cmd = CHILD_PROCESS_INIT;
 544         int i;
 545         struct object *o;
 546         char namebuf[42]; /* ^ + SHA-1 + LF */
 547
 548         if (do_reachable_revlist(&cmd, src, reachable) < 0)
 549                 return -1;
 550
 551         while ((i = read_in_full(cmd.out, namebuf, 41)) == 41) {
 552                 struct object_id sha1;
 553
 554                 if (namebuf[40] != '\n' || get_oid_hex(namebuf, &sha1))
 555                         break;
 556
 557                 o = lookup_object(sha1.hash);
 558                 if (o && o->type == OBJ_COMMIT) {
 559                         o->flags &= ~TMP_MARK;
 560                 }
 561         }
 562         for (i = get_max_object_index(); 0 < i; i--) {
 563                 o = get_indexed_object(i - 1);
 564                 if (o && o->type == OBJ_COMMIT &&
 565                     (o->flags & TMP_MARK)) {
 566                         add_object_array(o, NULL, reachable);
 567                                 o->flags &= ~TMP_MARK;
 568                 }
 569         }
 570         close(cmd.out);
 571
 572         if (finish_command(&cmd))
 573                 return -1;
 574
 575         return 0;
 576 }
 577
 578 static int has_unreachable(struct object_array *src)
 579 {
 580         struct child_process cmd = CHILD_PROCESS_INIT;
 581         char buf[1];
 582         int i;
 583
 584         if (do_reachable_revlist(&cmd, src, NULL) < 0)
 585                 return 1;
 586
 587         /*
 588          * The commits out of the rev-list are not ancestors of
 589          * our ref.
 590          */
 591         i = read_in_full(cmd.out, buf, 1);
 592         if (i)
 593                 goto error;
 594         close(cmd.out);
 595         cmd.out = -1;
 596
 597         /*
 598          * rev-list may have died by encountering a bad commit
 599          * in the history, in which case we do want to bail out
 600          * even when it showed no commit.
 601          */
 602         if (finish_command(&cmd))
 603                 goto error;
 604
 605         /* All the non-tip ones are ancestors of what we advertised */
 606         return 0;
 607
 608 error:
 609         sigchain_pop(SIGPIPE);
 610         if (cmd.out >= 0)
 611                 close(cmd.out);
 612         return 1;
 613 }
 614
 615 static void check_non_tip(void)
 616 {
 617         int i;
 618
 619         /*
 620          * In the normal in-process case without
 621          * uploadpack.allowReachableSHA1InWant,
 622          * non-tip requests can never happen.
 623          */
 624         if (!stateless_rpc && !(allow_unadvertised_object_request & ALLOW_REACHABLE_SHA1))
 625                 goto error;
 626         if (!has_unreachable(&want_obj))
 627                 /* All the non-tip ones are ancestors of what we advertised */
 628                 return;
 629
 630 error:
 631         /* Pick one of them (we know there at least is one) */
 632         for (i = 0; i < want_obj.nr; i++) {
 633                 struct object *o = want_obj.objects[i].item;
 634                 if (!is_our_ref(o))
 635                         die("git upload-pack: not our ref %s",
 636                             oid_to_hex(&o->oid));
 637         }
 638 }
 639
 640 static void send_shallow(struct commit_list *result)
 641 {
 642         while (result) {
 643                 struct object *object = &result->item->object;
 644                 if (!(object->flags & (CLIENT_SHALLOW|NOT_SHALLOW))) {
 645                         packet_write_fmt(1, "shallow %s",
 646                                          oid_to_hex(&object->oid));
 647                         register_shallow(&object->oid);
 648                         shallow_nr++;
 649                 }
 650                 result = result->next;
 651         }
 652 }
 653
 654 static void send_unshallow(const struct object_array *shallows)
 655 {
 656         int i;
 657
 658         for (i = 0; i < shallows->nr; i++) {
 659                 struct object *object = shallows->objects[i].item;
 660                 if (object->flags & NOT_SHALLOW) {
 661                         struct commit_list *parents;
 662                         packet_write_fmt(1, "unshallow %s",
 663                                          oid_to_hex(&object->oid));
 664                         object->flags &= ~CLIENT_SHALLOW;
 665                         /*
 666                          * We want to _register_ "object" as shallow, but we
 667                          * also need to traverse object's parents to deepen a
 668                          * shallow clone. Unregister it for now so we can
 669                          * parse and add the parents to the want list, then
 670                          * re-register it.
 671                          */
 672                         unregister_shallow(&object->oid);
 673                         object->parsed = 0;
 674                         parse_commit_or_die((struct commit *)object);
 675                         parents = ((struct commit *)object)->parents;
 676                         while (parents) {
 677                                 add_object_array(&parents->item->object,
 678                                                  NULL, &want_obj);
 679                                 parents = parents->next;
 680                         }
 681                         add_object_array(object, NULL, &extra_edge_obj);
 682                 }
 683                 /* make sure commit traversal conforms to client */
 684                 register_shallow(&object->oid);
 685         }
 686 }
 687
 688 static void deepen(int depth, int deepen_relative,
 689                    struct object_array *shallows)
 690 {
 691         if (depth == INFINITE_DEPTH && !is_repository_shallow()) {
 692                 int i;
 693
 694                 for (i = 0; i < shallows->nr; i++) {
 695                         struct object *object = shallows->objects[i].item;
 696                         object->flags |= NOT_SHALLOW;
 697                 }
 698         } else if (deepen_relative) {
 699                 struct object_array reachable_shallows = OBJECT_ARRAY_INIT;
 700                 struct commit_list *result;
 701
 702                 get_reachable_list(shallows, &reachable_shallows);
 703                 result = get_shallow_commits(&reachable_shallows,
 704                                              depth + 1,
 705                                              SHALLOW, NOT_SHALLOW);
 706                 send_shallow(result);
 707                 free_commit_list(result);
 708                 object_array_clear(&reachable_shallows);
 709         } else {
 710                 struct commit_list *result;
 711
 712                 result = get_shallow_commits(&want_obj, depth,
 713                                              SHALLOW, NOT_SHALLOW);
 714                 send_shallow(result);
 715                 free_commit_list(result);
 716         }
 717
 718         send_unshallow(shallows);
 719         packet_flush(1);
 720 }
 721
 722 static void deepen_by_rev_list(int ac, const char **av,
 723                                struct object_array *shallows)
 724 {
 725         struct commit_list *result;
 726
 727         result = get_shallow_commits_by_rev_list(ac, av, SHALLOW, NOT_SHALLOW);
 728         send_shallow(result);
 729         free_commit_list(result);
 730         send_unshallow(shallows);
 731         packet_flush(1);
 732 }
 733
 734 static void receive_needs(void)
 735 {
 736         struct object_array shallows = OBJECT_ARRAY_INIT;
 737         struct string_list deepen_not = STRING_LIST_INIT_DUP;
 738         int depth = 0;
 739         int has_non_tip = 0;
 740         timestamp_t deepen_since = 0;
 741         int deepen_rev_list = 0;
 742
 743         shallow_nr = 0;
 744         for (;;) {
 745                 struct object *o;
 746                 const char *features;
 747                 struct object_id oid_buf;
 748                 char *line = packet_read_line(0, NULL);
 749                 const char *arg;
 750
 751                 reset_timeout();
 752                 if (!line)
 753                         break;
 754
 755                 if (skip_prefix(line, "shallow ", &arg)) {
 756                         struct object_id oid;
 757                         struct object *object;
 758                         if (get_oid_hex(arg, &oid))
 759                                 die("invalid shallow line: %s", line);
 760                         object = parse_object(&oid);
 761                         if (!object)
 762                                 continue;
 763                         if (object->type != OBJ_COMMIT)
 764                                 die("invalid shallow object %s", oid_to_hex(&oid));
 765                         if (!(object->flags & CLIENT_SHALLOW)) {
 766                                 object->flags |= CLIENT_SHALLOW;
 767                                 add_object_array(object, NULL, &shallows);
 768                         }
 769                         continue;
 770                 }
 771                 if (skip_prefix(line, "deepen ", &arg)) {
 772                         char *end = NULL;
 773                         depth = strtol(arg, &end, 0);
 774                         if (!end || *end || depth <= 0)
 775                                 die("Invalid deepen: %s", line);
 776                         continue;
 777                 }
 778                 if (skip_prefix(line, "deepen-since ", &arg)) {
 779                         char *end = NULL;
 780                         deepen_since = parse_timestamp(arg, &end, 0);
 781                         if (!end || *end || !deepen_since ||
 782                             /* revisions.c's max_age -1 is special */
 783                             deepen_since == -1)
 784                                 die("Invalid deepen-since: %s", line);
 785                         deepen_rev_list = 1;
 786                         continue;
 787                 }
 788                 if (skip_prefix(line, "deepen-not ", &arg)) {
 789                         char *ref = NULL;
 790                         struct object_id oid;
 791                         if (expand_ref(arg, strlen(arg), &oid, &ref) != 1)
 792                                 die("git upload-pack: ambiguous deepen-not: %s", line);
 793                         string_list_append(&deepen_not, ref);
 794                         free(ref);
 795                         deepen_rev_list = 1;
 796                         continue;
 797                 }
 798                 if (!skip_prefix(line, "want ", &arg) ||
 799                     get_oid_hex(arg, &oid_buf))
 800                         die("git upload-pack: protocol error, "
 801                             "expected to get sha, not '%s'", line);
 802
 803                 features = arg + 40;
 804
 805                 if (parse_feature_request(features, "deepen-relative"))
 806                         deepen_relative = 1;
 807                 if (parse_feature_request(features, "multi_ack_detailed"))
 808                         multi_ack = 2;
 809                 else if (parse_feature_request(features, "multi_ack"))
 810                         multi_ack = 1;
 811                 if (parse_feature_request(features, "no-done"))
 812                         no_done = 1;
 813                 if (parse_feature_request(features, "thin-pack"))
 814                         use_thin_pack = 1;
 815                 if (parse_feature_request(features, "ofs-delta"))
 816                         use_ofs_delta = 1;
 817                 if (parse_feature_request(features, "side-band-64k"))
 818                         use_sideband = LARGE_PACKET_MAX;
 819                 else if (parse_feature_request(features, "side-band"))
 820                         use_sideband = DEFAULT_PACKET_MAX;
 821                 if (parse_feature_request(features, "no-progress"))
 822                         no_progress = 1;
 823                 if (parse_feature_request(features, "include-tag"))
 824                         use_include_tag = 1;
 825
 826                 o = parse_object(&oid_buf);
 827                 if (!o) {
 828                         packet_write_fmt(1,
 829                                          "ERR upload-pack: not our ref %s",
 830                                          oid_to_hex(&oid_buf));
 831                         die("git upload-pack: not our ref %s",
 832                             oid_to_hex(&oid_buf));
 833                 }
 834                 if (!(o->flags & WANTED)) {
 835                         o->flags |= WANTED;
 836                         if (!((allow_unadvertised_object_request & ALLOW_ANY_SHA1) == ALLOW_ANY_SHA1
 837                               || is_our_ref(o)))
 838                                 has_non_tip = 1;
 839                         add_object_array(o, NULL, &want_obj);
 840                 }
 841         }
 842
 843         /*
 844          * We have sent all our refs already, and the other end
 845          * should have chosen out of them. When we are operating
 846          * in the stateless RPC mode, however, their choice may
 847          * have been based on the set of older refs advertised
 848          * by another process that handled the initial request.
 849          */
 850         if (has_non_tip)
 851                 check_non_tip();
 852
 853         if (!use_sideband && daemon_mode)
 854                 no_progress = 1;
 855
 856         if (depth == 0 && !deepen_rev_list && shallows.nr == 0)
 857                 return;
 858         if (depth > 0 && deepen_rev_list)
 859                 die("git upload-pack: deepen and deepen-since (or deepen-not) cannot be used together");
 860         if (depth > 0)
 861                 deepen(depth, deepen_relative, &shallows);
 862         else if (deepen_rev_list) {
 863                 struct argv_array av = ARGV_ARRAY_INIT;
 864                 int i;
 865
 866                 argv_array_push(&av, "rev-list");
 867                 if (deepen_since)
 868                         argv_array_pushf(&av, "--max-age=%"PRItime, deepen_since);
 869                 if (deepen_not.nr) {
 870                         argv_array_push(&av, "--not");
 871                         for (i = 0; i < deepen_not.nr; i++) {
 872                                 struct string_list_item *s = deepen_not.items + i;
 873                                 argv_array_push(&av, s->string);
 874                         }
 875                         argv_array_push(&av, "--not");
 876                 }
 877                 for (i = 0; i < want_obj.nr; i++) {
 878                         struct object *o = want_obj.objects[i].item;
 879                         argv_array_push(&av, oid_to_hex(&o->oid));
 880                 }
 881                 deepen_by_rev_list(av.argc, av.argv, &shallows);
 882                 argv_array_clear(&av);
 883         }
 884         else
 885                 if (shallows.nr > 0) {
 886                         int i;
 887                         for (i = 0; i < shallows.nr; i++)
 888                                 register_shallow(&shallows.objects[i].item->oid);
 889                 }
 890
 891         shallow_nr += shallows.nr;
 892         object_array_clear(&shallows);
 893 }
 894
 895 /* return non-zero if the ref is hidden, otherwise 0 */
 896 static int mark_our_ref(const char *refname, const char *refname_full,
 897                         const struct object_id *oid)
 898 {
 899         struct object *o = lookup_unknown_object(oid->hash);
 900
 901         if (ref_is_hidden(refname, refname_full)) {
 902                 o->flags |= HIDDEN_REF;
 903                 return 1;
 904         }
 905         o->flags |= OUR_REF;
 906         return 0;
 907 }
 908
 909 static int check_ref(const char *refname_full, const struct object_id *oid,
 910                      int flag, void *cb_data)
 911 {
 912         const char *refname = strip_namespace(refname_full);
 913
 914         mark_our_ref(refname, refname_full, oid);
 915         return 0;
 916 }
 917
 918 static void format_symref_info(struct strbuf *buf, struct string_list *symref)
 919 {
 920         struct string_list_item *item;
 921
 922         if (!symref->nr)
 923                 return;
 924         for_each_string_list_item(item, symref)
 925                 strbuf_addf(buf, " symref=%s:%s", item->string, (char *)item->util);
 926 }
 927
 928 static int send_ref(const char *refname, const struct object_id *oid,
 929                     int flag, void *cb_data)
 930 {
 931         static const char *capabilities = "multi_ack thin-pack side-band"
 932                 " side-band-64k ofs-delta shallow deepen-since deepen-not"
 933                 " deepen-relative no-progress include-tag multi_ack_detailed";
 934         const char *refname_nons = strip_namespace(refname);
 935         struct object_id peeled;
 936
 937         if (mark_our_ref(refname_nons, refname, oid))
 938                 return 0;
 939
 940         if (capabilities) {
 941                 struct strbuf symref_info = STRBUF_INIT;
 942
 943                 format_symref_info(&symref_info, cb_data);
 944                 packet_write_fmt(1, "%s %s%c%s%s%s%s%s agent=%s\n",
 945                              oid_to_hex(oid), refname_nons,
 946                              0, capabilities,
 947                              (allow_unadvertised_object_request & ALLOW_TIP_SHA1) ?
 948                                      " allow-tip-sha1-in-want" : "",
 949                              (allow_unadvertised_object_request & ALLOW_REACHABLE_SHA1) ?
 950                                      " allow-reachable-sha1-in-want" : "",
 951                              stateless_rpc ? " no-done" : "",
 952                              symref_info.buf,
 953                              git_user_agent_sanitized());
 954                 strbuf_release(&symref_info);
 955         } else {
 956                 packet_write_fmt(1, "%s %s\n", oid_to_hex(oid), refname_nons);
 957         }
 958         capabilities = NULL;
 959         if (!peel_ref(refname, &peeled))
 960                 packet_write_fmt(1, "%s %s^{}\n", oid_to_hex(&peeled), refname_nons);
 961         return 0;
 962 }
 963
 964 static int find_symref(const char *refname, const struct object_id *oid,
 965                        int flag, void *cb_data)
 966 {
 967         const char *symref_target;
 968         struct string_list_item *item;
 969
 970         if ((flag & REF_ISSYMREF) == 0)
 971                 return 0;
 972         symref_target = resolve_ref_unsafe(refname, 0, NULL, &flag);
 973         if (!symref_target || (flag & REF_ISSYMREF) == 0)
 974                 die("'%s' is a symref but it is not?", refname);
 975         item = string_list_append(cb_data, refname);
 976         item->util = xstrdup(symref_target);
 977         return 0;
 978 }
 979
 980 static void upload_pack(void)
 981 {
 982         struct string_list symref = STRING_LIST_INIT_DUP;
 983
 984         head_ref_namespaced(find_symref, &symref);
 985
 986         if (advertise_refs || !stateless_rpc) {
 987                 reset_timeout();
 988                 head_ref_namespaced(send_ref, &symref);
 989                 for_each_namespaced_ref(send_ref, &symref);
 990                 advertise_shallow_grafts(1);
 991                 packet_flush(1);
 992         } else {
 993                 head_ref_namespaced(check_ref, NULL);
 994                 for_each_namespaced_ref(check_ref, NULL);
 995         }
 996         string_list_clear(&symref, 1);
 997         if (advertise_refs)
 998                 return;
 999
1000         receive_needs();
1001         if (want_obj.nr) {
1002                 get_common_commits();
1003                 create_pack_file();
1004         }
1005 }
1006
1007 static int upload_pack_config(const char *var, const char *value, void *unused)
1008 {
1009         if (!strcmp("uploadpack.allowtipsha1inwant", var)) {
1010                 if (git_config_bool(var, value))
1011                         allow_unadvertised_object_request |= ALLOW_TIP_SHA1;
1012                 else
1013                         allow_unadvertised_object_request &= ~ALLOW_TIP_SHA1;
1014         } else if (!strcmp("uploadpack.allowreachablesha1inwant", var)) {
1015                 if (git_config_bool(var, value))
1016                         allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
1017                 else
1018                         allow_unadvertised_object_request &= ~ALLOW_REACHABLE_SHA1;
1019         } else if (!strcmp("uploadpack.allowanysha1inwant", var)) {
1020                 if (git_config_bool(var, value))
1021                         allow_unadvertised_object_request |= ALLOW_ANY_SHA1;
1022                 else
1023                         allow_unadvertised_object_request &= ~ALLOW_ANY_SHA1;
1024         } else if (!strcmp("uploadpack.keepalive", var)) {
1025                 keepalive = git_config_int(var, value);
1026                 if (!keepalive)
1027                         keepalive = -1;
1028         } else if (current_config_scope() != CONFIG_SCOPE_REPO) {
1029                 if (!strcmp("uploadpack.packobjectshook", var))
1030                         return git_config_string(&pack_objects_hook, var, value);
1031         }
1032         return parse_hide_refs_config(var, value, "uploadpack");
1033 }
1034
1035 int cmd_main(int argc, const char **argv)
1036 {
1037         const char *dir;
1038         int strict = 0;
1039         struct option options[] = {
1040                 OPT_BOOL(0, "stateless-rpc", &stateless_rpc,
1041                          N_("quit after a single request/response exchange")),
1042                 OPT_BOOL(0, "advertise-refs", &advertise_refs,
1043                          N_("exit immediately after initial ref advertisement")),
1044                 OPT_BOOL(0, "strict", &strict,
1045                          N_("do not try <directory>/.git/ if <directory> is no Git directory")),
1046                 OPT_INTEGER(0, "timeout", &timeout,
1047                             N_("interrupt transfer after <n> seconds of inactivity")),
1048                 OPT_END()
1049         };
1050
1051         packet_trace_identity("upload-pack");
1052         check_replace_refs = 0;
1053
1054         argc = parse_options(argc, argv, NULL, options, upload_pack_usage, 0);
1055
1056         if (argc != 1)
1057                 usage_with_options(upload_pack_usage, options);
1058
1059         if (timeout)
1060                 daemon_mode = 1;
1061
1062         setup_path();
1063
1064         dir = argv[0];
1065
1066         if (!enter_repo(dir, strict))
1067                 die("'%s' does not appear to be a git repository", dir);
1068
1069         git_config(upload_pack_config, NULL);
1070
1071         switch (determine_protocol_version_server()) {
1072         case protocol_v1:
1073                 /*
1074                  * v1 is just the original protocol with a version string,
1075                  * so just fall through after writing the version string.
1076                  */
1077                 if (advertise_refs || !stateless_rpc)
1078                         packet_write_fmt(1, "version 1\n");
1079
1080                 /* fallthrough */
1081         case protocol_v0:
1082                 upload_pack();
1083                 break;
1084         case protocol_unknown_version:
1085                 BUG("unknown protocol version");
1086         }
1087
1088         return 0;
1089 }