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
  18 static const char upload_pack_usage[] = "git upload-pack [--strict] [--timeout=<n>] <dir>";
  19
  20 /* bits #0..7 in revision.h, #8..10 in commit.c */
  21 #define THEY_HAVE       (1u << 11)
  22 #define OUR_REF         (1u << 12)
  23 #define WANTED          (1u << 13)
  24 #define COMMON_KNOWN    (1u << 14)
  25 #define REACHABLE       (1u << 15)
  26
  27 #define SHALLOW         (1u << 16)
  28 #define NOT_SHALLOW     (1u << 17)
  29 #define CLIENT_SHALLOW  (1u << 18)
  30 #define HIDDEN_REF      (1u << 19)
  31
  32 static unsigned long oldest_have;
  33
  34 static int multi_ack;
  35 static int no_done;
  36 static int use_thin_pack, use_ofs_delta, use_include_tag;
  37 static int no_progress, daemon_mode;
  38 static int allow_tip_sha1_in_want;
  39 static int shallow_nr;
  40 static struct object_array have_obj;
  41 static struct object_array want_obj;
  42 static struct object_array extra_edge_obj;
  43 static unsigned int timeout;
  44 static int keepalive = 5;
  45 /* 0 for no sideband,
  46  * otherwise maximum packet size (up to 65520 bytes).
  47  */
  48 static int use_sideband;
  49 static int advertise_refs;
  50 static int stateless_rpc;
  51
  52 static void reset_timeout(void)
  53 {
  54         alarm(timeout);
  55 }
  56
  57 static ssize_t send_client_data(int fd, const char *data, ssize_t sz)
  58 {
  59         if (use_sideband)
  60                 return send_sideband(1, fd, data, sz, use_sideband);
  61         if (fd == 3)
  62                 /* emergency quit */
  63                 fd = 2;
  64         if (fd == 2) {
  65                 /* XXX: are we happy to lose stuff here? */
  66                 xwrite(fd, data, sz);
  67                 return sz;
  68         }
  69         write_or_die(fd, data, sz);
  70         return sz;
  71 }
  72
  73 static void create_pack_file(void)
  74 {
  75         struct child_process pack_objects;
  76         char data[8193], progress[128];
  77         char abort_msg[] = "aborting due to possible repository "
  78                 "corruption on the remote side.";
  79         int buffered = -1;
  80         ssize_t sz;
  81         const char *argv[12];
  82         int i, arg = 0;
  83         FILE *pipe_fd;
  84         char *shallow_file = NULL;
  85
  86         if (shallow_nr) {
  87                 shallow_file = setup_temporary_shallow();
  88                 argv[arg++] = "--shallow-file";
  89                 argv[arg++] = shallow_file;
  90         }
  91         argv[arg++] = "pack-objects";
  92         argv[arg++] = "--revs";
  93         if (use_thin_pack)
  94                 argv[arg++] = "--thin";
  95
  96         argv[arg++] = "--stdout";
  97         if (!no_progress)
  98                 argv[arg++] = "--progress";
  99         if (use_ofs_delta)
 100                 argv[arg++] = "--delta-base-offset";
 101         if (use_include_tag)
 102                 argv[arg++] = "--include-tag";
 103         argv[arg++] = NULL;
 104
 105         memset(&pack_objects, 0, sizeof(pack_objects));
 106         pack_objects.in = -1;
 107         pack_objects.out = -1;
 108         pack_objects.err = -1;
 109         pack_objects.git_cmd = 1;
 110         pack_objects.argv = argv;
 111
 112         if (start_command(&pack_objects))
 113                 die("git upload-pack: unable to fork git-pack-objects");
 114
 115         pipe_fd = xfdopen(pack_objects.in, "w");
 116
 117         for (i = 0; i < want_obj.nr; i++)
 118                 fprintf(pipe_fd, "%s\n",
 119                         sha1_to_hex(want_obj.objects[i].item->sha1));
 120         fprintf(pipe_fd, "--not\n");
 121         for (i = 0; i < have_obj.nr; i++)
 122                 fprintf(pipe_fd, "%s\n",
 123                         sha1_to_hex(have_obj.objects[i].item->sha1));
 124         for (i = 0; i < extra_edge_obj.nr; i++)
 125                 fprintf(pipe_fd, "%s\n",
 126                         sha1_to_hex(extra_edge_obj.objects[i].item->sha1));
 127         fprintf(pipe_fd, "\n");
 128         fflush(pipe_fd);
 129         fclose(pipe_fd);
 130
 131         /* We read from pack_objects.err to capture stderr output for
 132          * progress bar, and pack_objects.out to capture the pack data.
 133          */
 134
 135         while (1) {
 136                 struct pollfd pfd[2];
 137                 int pe, pu, pollsize;
 138                 int ret;
 139
 140                 reset_timeout();
 141
 142                 pollsize = 0;
 143                 pe = pu = -1;
 144
 145                 if (0 <= pack_objects.out) {
 146                         pfd[pollsize].fd = pack_objects.out;
 147                         pfd[pollsize].events = POLLIN;
 148                         pu = pollsize;
 149                         pollsize++;
 150                 }
 151                 if (0 <= pack_objects.err) {
 152                         pfd[pollsize].fd = pack_objects.err;
 153                         pfd[pollsize].events = POLLIN;
 154                         pe = pollsize;
 155                         pollsize++;
 156                 }
 157
 158                 if (!pollsize)
 159                         break;
 160
 161                 ret = poll(pfd, pollsize, 1000 * keepalive);
 162                 if (ret < 0) {
 163                         if (errno != EINTR) {
 164                                 error("poll failed, resuming: %s",
 165                                       strerror(errno));
 166                                 sleep(1);
 167                         }
 168                         continue;
 169                 }
 170                 if (0 <= pe && (pfd[pe].revents & (POLLIN|POLLHUP))) {
 171                         /* Status ready; we ship that in the side-band
 172                          * or dump to the standard error.
 173                          */
 174                         sz = xread(pack_objects.err, progress,
 175                                   sizeof(progress));
 176                         if (0 < sz)
 177                                 send_client_data(2, progress, sz);
 178                         else if (sz == 0) {
 179                                 close(pack_objects.err);
 180                                 pack_objects.err = -1;
 181                         }
 182                         else
 183                                 goto fail;
 184                         /* give priority to status messages */
 185                         continue;
 186                 }
 187                 if (0 <= pu && (pfd[pu].revents & (POLLIN|POLLHUP))) {
 188                         /* Data ready; we keep the last byte to ourselves
 189                          * in case we detect broken rev-list, so that we
 190                          * can leave the stream corrupted.  This is
 191                          * unfortunate -- unpack-objects would happily
 192                          * accept a valid packdata with trailing garbage,
 193                          * so appending garbage after we pass all the
 194                          * pack data is not good enough to signal
 195                          * breakage to downstream.
 196                          */
 197                         char *cp = data;
 198                         ssize_t outsz = 0;
 199                         if (0 <= buffered) {
 200                                 *cp++ = buffered;
 201                                 outsz++;
 202                         }
 203                         sz = xread(pack_objects.out, cp,
 204                                   sizeof(data) - outsz);
 205                         if (0 < sz)
 206                                 ;
 207                         else if (sz == 0) {
 208                                 close(pack_objects.out);
 209                                 pack_objects.out = -1;
 210                         }
 211                         else
 212                                 goto fail;
 213                         sz += outsz;
 214                         if (1 < sz) {
 215                                 buffered = data[sz-1] & 0xFF;
 216                                 sz--;
 217                         }
 218                         else
 219                                 buffered = -1;
 220                         sz = send_client_data(1, data, sz);
 221                         if (sz < 0)
 222                                 goto fail;
 223                 }
 224
 225                 /*
 226                  * We hit the keepalive timeout without saying anything; send
 227                  * an empty message on the data sideband just to let the other
 228                  * side know we're still working on it, but don't have any data
 229                  * yet.
 230                  *
 231                  * If we don't have a sideband channel, there's no room in the
 232                  * protocol to say anything, so those clients are just out of
 233                  * luck.
 234                  */
 235                 if (!ret && use_sideband) {
 236                         static const char buf[] = "0005\1";
 237                         write_or_die(1, buf, 5);
 238                 }
 239         }
 240
 241         if (finish_command(&pack_objects)) {
 242                 error("git upload-pack: git-pack-objects died with error.");
 243                 goto fail;
 244         }
 245         if (shallow_file) {
 246                 if (*shallow_file)
 247                         unlink(shallow_file);
 248                 free(shallow_file);
 249         }
 250
 251         /* flush the data */
 252         if (0 <= buffered) {
 253                 data[0] = buffered;
 254                 sz = send_client_data(1, data, 1);
 255                 if (sz < 0)
 256                         goto fail;
 257                 fprintf(stderr, "flushed.\n");
 258         }
 259         if (use_sideband)
 260                 packet_flush(1);
 261         return;
 262
 263  fail:
 264         send_client_data(3, abort_msg, sizeof(abort_msg));
 265         die("git upload-pack: %s", abort_msg);
 266 }
 267
 268 static int got_sha1(char *hex, unsigned char *sha1)
 269 {
 270         struct object *o;
 271         int we_knew_they_have = 0;
 272
 273         if (get_sha1_hex(hex, sha1))
 274                 die("git upload-pack: expected SHA1 object, got '%s'", hex);
 275         if (!has_sha1_file(sha1))
 276                 return -1;
 277
 278         o = parse_object(sha1);
 279         if (!o)
 280                 die("oops (%s)", sha1_to_hex(sha1));
 281         if (o->type == OBJ_COMMIT) {
 282                 struct commit_list *parents;
 283                 struct commit *commit = (struct commit *)o;
 284                 if (o->flags & THEY_HAVE)
 285                         we_knew_they_have = 1;
 286                 else
 287                         o->flags |= THEY_HAVE;
 288                 if (!oldest_have || (commit->date < oldest_have))
 289                         oldest_have = commit->date;
 290                 for (parents = commit->parents;
 291                      parents;
 292                      parents = parents->next)
 293                         parents->item->object.flags |= THEY_HAVE;
 294         }
 295         if (!we_knew_they_have) {
 296                 add_object_array(o, NULL, &have_obj);
 297                 return 1;
 298         }
 299         return 0;
 300 }
 301
 302 static int reachable(struct commit *want)
 303 {
 304         struct commit_list *work = NULL;
 305
 306         commit_list_insert_by_date(want, &work);
 307         while (work) {
 308                 struct commit_list *list = work->next;
 309                 struct commit *commit = work->item;
 310                 free(work);
 311                 work = list;
 312
 313                 if (commit->object.flags & THEY_HAVE) {
 314                         want->object.flags |= COMMON_KNOWN;
 315                         break;
 316                 }
 317                 if (!commit->object.parsed)
 318                         parse_object(commit->object.sha1);
 319                 if (commit->object.flags & REACHABLE)
 320                         continue;
 321                 commit->object.flags |= REACHABLE;
 322                 if (commit->date < oldest_have)
 323                         continue;
 324                 for (list = commit->parents; list; list = list->next) {
 325                         struct commit *parent = list->item;
 326                         if (!(parent->object.flags & REACHABLE))
 327                                 commit_list_insert_by_date(parent, &work);
 328                 }
 329         }
 330         want->object.flags |= REACHABLE;
 331         clear_commit_marks(want, REACHABLE);
 332         free_commit_list(work);
 333         return (want->object.flags & COMMON_KNOWN);
 334 }
 335
 336 static int ok_to_give_up(void)
 337 {
 338         int i;
 339
 340         if (!have_obj.nr)
 341                 return 0;
 342
 343         for (i = 0; i < want_obj.nr; i++) {
 344                 struct object *want = want_obj.objects[i].item;
 345
 346                 if (want->flags & COMMON_KNOWN)
 347                         continue;
 348                 want = deref_tag(want, "a want line", 0);
 349                 if (!want || want->type != OBJ_COMMIT) {
 350                         /* no way to tell if this is reachable by
 351                          * looking at the ancestry chain alone, so
 352                          * leave a note to ourselves not to worry about
 353                          * this object anymore.
 354                          */
 355                         want_obj.objects[i].item->flags |= COMMON_KNOWN;
 356                         continue;
 357                 }
 358                 if (!reachable((struct commit *)want))
 359                         return 0;
 360         }
 361         return 1;
 362 }
 363
 364 static int get_common_commits(void)
 365 {
 366         unsigned char sha1[20];
 367         char last_hex[41];
 368         int got_common = 0;
 369         int got_other = 0;
 370         int sent_ready = 0;
 371
 372         save_commit_buffer = 0;
 373
 374         for (;;) {
 375                 char *line = packet_read_line(0, NULL);
 376                 reset_timeout();
 377
 378                 if (!line) {
 379                         if (multi_ack == 2 && got_common
 380                             && !got_other && ok_to_give_up()) {
 381                                 sent_ready = 1;
 382                                 packet_write(1, "ACK %s ready\n", last_hex);
 383                         }
 384                         if (have_obj.nr == 0 || multi_ack)
 385                                 packet_write(1, "NAK\n");
 386
 387                         if (no_done && sent_ready) {
 388                                 packet_write(1, "ACK %s\n", last_hex);
 389                                 return 0;
 390                         }
 391                         if (stateless_rpc)
 392                                 exit(0);
 393                         got_common = 0;
 394                         got_other = 0;
 395                         continue;
 396                 }
 397                 if (!prefixcmp(line, "have ")) {
 398                         switch (got_sha1(line+5, sha1)) {
 399                         case -1: /* they have what we do not */
 400                                 got_other = 1;
 401                                 if (multi_ack && ok_to_give_up()) {
 402                                         const char *hex = sha1_to_hex(sha1);
 403                                         if (multi_ack == 2) {
 404                                                 sent_ready = 1;
 405                                                 packet_write(1, "ACK %s ready\n", hex);
 406                                         } else
 407                                                 packet_write(1, "ACK %s continue\n", hex);
 408                                 }
 409                                 break;
 410                         default:
 411                                 got_common = 1;
 412                                 memcpy(last_hex, sha1_to_hex(sha1), 41);
 413                                 if (multi_ack == 2)
 414                                         packet_write(1, "ACK %s common\n", last_hex);
 415                                 else if (multi_ack)
 416                                         packet_write(1, "ACK %s continue\n", last_hex);
 417                                 else if (have_obj.nr == 1)
 418                                         packet_write(1, "ACK %s\n", last_hex);
 419                                 break;
 420                         }
 421                         continue;
 422                 }
 423                 if (!strcmp(line, "done")) {
 424                         if (have_obj.nr > 0) {
 425                                 if (multi_ack)
 426                                         packet_write(1, "ACK %s\n", last_hex);
 427                                 return 0;
 428                         }
 429                         packet_write(1, "NAK\n");
 430                         return -1;
 431                 }
 432                 die("git upload-pack: expected SHA1 list, got '%s'", line);
 433         }
 434 }
 435
 436 static int is_our_ref(struct object *o)
 437 {
 438         return o->flags &
 439                 ((allow_tip_sha1_in_want ? HIDDEN_REF : 0) | OUR_REF);
 440 }
 441
 442 static void check_non_tip(void)
 443 {
 444         static const char *argv[] = {
 445                 "rev-list", "--stdin", NULL,
 446         };
 447         static struct child_process cmd;
 448         struct object *o;
 449         char namebuf[42]; /* ^ + SHA-1 + LF */
 450         int i;
 451
 452         /* In the normal in-process case non-tip request can never happen */
 453         if (!stateless_rpc)
 454                 goto error;
 455
 456         cmd.argv = argv;
 457         cmd.git_cmd = 1;
 458         cmd.no_stderr = 1;
 459         cmd.in = -1;
 460         cmd.out = -1;
 461
 462         if (start_command(&cmd))
 463                 goto error;
 464
 465         /*
 466          * If rev-list --stdin encounters an unknown commit, it
 467          * terminates, which will cause SIGPIPE in the write loop
 468          * below.
 469          */
 470         sigchain_push(SIGPIPE, SIG_IGN);
 471
 472         namebuf[0] = '^';
 473         namebuf[41] = '\n';
 474         for (i = get_max_object_index(); 0 < i; ) {
 475                 o = get_indexed_object(--i);
 476                 if (!o)
 477                         continue;
 478                 if (!is_our_ref(o))
 479                         continue;
 480                 memcpy(namebuf + 1, sha1_to_hex(o->sha1), 40);
 481                 if (write_in_full(cmd.in, namebuf, 42) < 0)
 482                         goto error;
 483         }
 484         namebuf[40] = '\n';
 485         for (i = 0; i < want_obj.nr; i++) {
 486                 o = want_obj.objects[i].item;
 487                 if (is_our_ref(o))
 488                         continue;
 489                 memcpy(namebuf, sha1_to_hex(o->sha1), 40);
 490                 if (write_in_full(cmd.in, namebuf, 41) < 0)
 491                         goto error;
 492         }
 493         close(cmd.in);
 494
 495         sigchain_pop(SIGPIPE);
 496
 497         /*
 498          * The commits out of the rev-list are not ancestors of
 499          * our ref.
 500          */
 501         i = read_in_full(cmd.out, namebuf, 1);
 502         if (i)
 503                 goto error;
 504         close(cmd.out);
 505
 506         /*
 507          * rev-list may have died by encountering a bad commit
 508          * in the history, in which case we do want to bail out
 509          * even when it showed no commit.
 510          */
 511         if (finish_command(&cmd))
 512                 goto error;
 513
 514         /* All the non-tip ones are ancestors of what we advertised */
 515         return;
 516
 517 error:
 518         /* Pick one of them (we know there at least is one) */
 519         for (i = 0; i < want_obj.nr; i++) {
 520                 o = want_obj.objects[i].item;
 521                 if (!is_our_ref(o))
 522                         die("git upload-pack: not our ref %s",
 523                             sha1_to_hex(o->sha1));
 524         }
 525 }
 526
 527 static void receive_needs(void)
 528 {
 529         struct object_array shallows = OBJECT_ARRAY_INIT;
 530         int depth = 0;
 531         int has_non_tip = 0;
 532
 533         shallow_nr = 0;
 534         for (;;) {
 535                 struct object *o;
 536                 const char *features;
 537                 unsigned char sha1_buf[20];
 538                 char *line = packet_read_line(0, NULL);
 539                 reset_timeout();
 540                 if (!line)
 541                         break;
 542
 543                 if (!prefixcmp(line, "shallow ")) {
 544                         unsigned char sha1[20];
 545                         struct object *object;
 546                         if (get_sha1_hex(line + 8, sha1))
 547                                 die("invalid shallow line: %s", line);
 548                         object = parse_object(sha1);
 549                         if (!object)
 550                                 continue;
 551                         if (object->type != OBJ_COMMIT)
 552                                 die("invalid shallow object %s", sha1_to_hex(sha1));
 553                         if (!(object->flags & CLIENT_SHALLOW)) {
 554                                 object->flags |= CLIENT_SHALLOW;
 555                                 add_object_array(object, NULL, &shallows);
 556                         }
 557                         continue;
 558                 }
 559                 if (!prefixcmp(line, "deepen ")) {
 560                         char *end;
 561                         depth = strtol(line + 7, &end, 0);
 562                         if (end == line + 7 || depth <= 0)
 563                                 die("Invalid deepen: %s", line);
 564                         continue;
 565                 }
 566                 if (prefixcmp(line, "want ") ||
 567                     get_sha1_hex(line+5, sha1_buf))
 568                         die("git upload-pack: protocol error, "
 569                             "expected to get sha, not '%s'", line);
 570
 571                 features = line + 45;
 572
 573                 if (parse_feature_request(features, "multi_ack_detailed"))
 574                         multi_ack = 2;
 575                 else if (parse_feature_request(features, "multi_ack"))
 576                         multi_ack = 1;
 577                 if (parse_feature_request(features, "no-done"))
 578                         no_done = 1;
 579                 if (parse_feature_request(features, "thin-pack"))
 580                         use_thin_pack = 1;
 581                 if (parse_feature_request(features, "ofs-delta"))
 582                         use_ofs_delta = 1;
 583                 if (parse_feature_request(features, "side-band-64k"))
 584                         use_sideband = LARGE_PACKET_MAX;
 585                 else if (parse_feature_request(features, "side-band"))
 586                         use_sideband = DEFAULT_PACKET_MAX;
 587                 if (parse_feature_request(features, "no-progress"))
 588                         no_progress = 1;
 589                 if (parse_feature_request(features, "include-tag"))
 590                         use_include_tag = 1;
 591
 592                 o = parse_object(sha1_buf);
 593                 if (!o)
 594                         die("git upload-pack: not our ref %s",
 595                             sha1_to_hex(sha1_buf));
 596                 if (!(o->flags & WANTED)) {
 597                         o->flags |= WANTED;
 598                         if (!is_our_ref(o))
 599                                 has_non_tip = 1;
 600                         add_object_array(o, NULL, &want_obj);
 601                 }
 602         }
 603
 604         /*
 605          * We have sent all our refs already, and the other end
 606          * should have chosen out of them. When we are operating
 607          * in the stateless RPC mode, however, their choice may
 608          * have been based on the set of older refs advertised
 609          * by another process that handled the initial request.
 610          */
 611         if (has_non_tip)
 612                 check_non_tip();
 613
 614         if (!use_sideband && daemon_mode)
 615                 no_progress = 1;
 616
 617         if (depth == 0 && shallows.nr == 0)
 618                 return;
 619         if (depth > 0) {
 620                 struct commit_list *result = NULL, *backup = NULL;
 621                 int i;
 622                 if (depth == INFINITE_DEPTH)
 623                         for (i = 0; i < shallows.nr; i++) {
 624                                 struct object *object = shallows.objects[i].item;
 625                                 object->flags |= NOT_SHALLOW;
 626                         }
 627                 else
 628                         backup = result =
 629                                 get_shallow_commits(&want_obj, depth,
 630                                                     SHALLOW, NOT_SHALLOW);
 631                 while (result) {
 632                         struct object *object = &result->item->object;
 633                         if (!(object->flags & (CLIENT_SHALLOW|NOT_SHALLOW))) {
 634                                 packet_write(1, "shallow %s",
 635                                                 sha1_to_hex(object->sha1));
 636                                 register_shallow(object->sha1);
 637                                 shallow_nr++;
 638                         }
 639                         result = result->next;
 640                 }
 641                 free_commit_list(backup);
 642                 for (i = 0; i < shallows.nr; i++) {
 643                         struct object *object = shallows.objects[i].item;
 644                         if (object->flags & NOT_SHALLOW) {
 645                                 struct commit_list *parents;
 646                                 packet_write(1, "unshallow %s",
 647                                         sha1_to_hex(object->sha1));
 648                                 object->flags &= ~CLIENT_SHALLOW;
 649                                 /* make sure the real parents are parsed */
 650                                 unregister_shallow(object->sha1);
 651                                 object->parsed = 0;
 652                                 if (parse_commit((struct commit *)object))
 653                                         die("invalid commit");
 654                                 parents = ((struct commit *)object)->parents;
 655                                 while (parents) {
 656                                         add_object_array(&parents->item->object,
 657                                                         NULL, &want_obj);
 658                                         parents = parents->next;
 659                                 }
 660                                 add_object_array(object, NULL, &extra_edge_obj);
 661                         }
 662                         /* make sure commit traversal conforms to client */
 663                         register_shallow(object->sha1);
 664                 }
 665                 packet_flush(1);
 666         } else
 667                 if (shallows.nr > 0) {
 668                         int i;
 669                         for (i = 0; i < shallows.nr; i++)
 670                                 register_shallow(shallows.objects[i].item->sha1);
 671                 }
 672
 673         shallow_nr += shallows.nr;
 674         free(shallows.objects);
 675 }
 676
 677 /* return non-zero if the ref is hidden, otherwise 0 */
 678 static int mark_our_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 679 {
 680         struct object *o = lookup_unknown_object(sha1);
 681
 682         if (ref_is_hidden(refname)) {
 683                 o->flags |= HIDDEN_REF;
 684                 return 1;
 685         }
 686         if (!o)
 687                 die("git upload-pack: cannot find object %s:", sha1_to_hex(sha1));
 688         o->flags |= OUR_REF;
 689         return 0;
 690 }
 691
 692 static void format_symref_info(struct strbuf *buf, struct string_list *symref)
 693 {
 694         struct string_list_item *item;
 695
 696         if (!symref->nr)
 697                 return;
 698         for_each_string_list_item(item, symref)
 699                 strbuf_addf(buf, " symref=%s:%s", item->string, (char *)item->util);
 700 }
 701
 702 static int send_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 703 {
 704         static const char *capabilities = "multi_ack thin-pack side-band"
 705                 " side-band-64k ofs-delta shallow no-progress"
 706                 " include-tag multi_ack_detailed";
 707         const char *refname_nons = strip_namespace(refname);
 708         unsigned char peeled[20];
 709
 710         if (mark_our_ref(refname, sha1, flag, NULL))
 711                 return 0;
 712
 713         if (capabilities) {
 714                 struct strbuf symref_info = STRBUF_INIT;
 715
 716                 format_symref_info(&symref_info, cb_data);
 717                 packet_write(1, "%s %s%c%s%s%s%s agent=%s\n",
 718                              sha1_to_hex(sha1), refname_nons,
 719                              0, capabilities,
 720                              allow_tip_sha1_in_want ? " allow-tip-sha1-in-want" : "",
 721                              stateless_rpc ? " no-done" : "",
 722                              symref_info.buf,
 723                              git_user_agent_sanitized());
 724                 strbuf_release(&symref_info);
 725         } else {
 726                 packet_write(1, "%s %s\n", sha1_to_hex(sha1), refname_nons);
 727         }
 728         capabilities = NULL;
 729         if (!peel_ref(refname, peeled))
 730                 packet_write(1, "%s %s^{}\n", sha1_to_hex(peeled), refname_nons);
 731         return 0;
 732 }
 733
 734 static int find_symref(const char *refname, const unsigned char *sha1, int flag,
 735                        void *cb_data)
 736 {
 737         const char *symref_target;
 738         struct string_list_item *item;
 739         unsigned char unused[20];
 740
 741         if ((flag & REF_ISSYMREF) == 0)
 742                 return 0;
 743         symref_target = resolve_ref_unsafe(refname, unused, 0, &flag);
 744         if (!symref_target || (flag & REF_ISSYMREF) == 0)
 745                 die("'%s' is a symref but it is not?", refname);
 746         item = string_list_append(cb_data, refname);
 747         item->util = xstrdup(symref_target);
 748         return 0;
 749 }
 750
 751 static void upload_pack(void)
 752 {
 753         struct string_list symref = STRING_LIST_INIT_DUP;
 754
 755         head_ref_namespaced(find_symref, &symref);
 756
 757         if (advertise_refs || !stateless_rpc) {
 758                 reset_timeout();
 759                 head_ref_namespaced(send_ref, &symref);
 760                 for_each_namespaced_ref(send_ref, &symref);
 761                 packet_flush(1);
 762         } else {
 763                 head_ref_namespaced(mark_our_ref, NULL);
 764                 for_each_namespaced_ref(mark_our_ref, NULL);
 765         }
 766         string_list_clear(&symref, 1);
 767         if (advertise_refs)
 768                 return;
 769
 770         receive_needs();
 771         if (want_obj.nr) {
 772                 get_common_commits();
 773                 create_pack_file();
 774         }
 775 }
 776
 777 static int upload_pack_config(const char *var, const char *value, void *unused)
 778 {
 779         if (!strcmp("uploadpack.allowtipsha1inwant", var))
 780                 allow_tip_sha1_in_want = git_config_bool(var, value);
 781         else if (!strcmp("uploadpack.keepalive", var)) {
 782                 keepalive = git_config_int(var, value);
 783                 if (!keepalive)
 784                         keepalive = -1;
 785         }
 786         return parse_hide_refs_config(var, value, "uploadpack");
 787 }
 788
 789 int main(int argc, char **argv)
 790 {
 791         char *dir;
 792         int i;
 793         int strict = 0;
 794
 795         git_setup_gettext();
 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         git_config(upload_pack_config, NULL);
 841         upload_pack();
 842         return 0;
 843 }