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 "repository.h"
   7 #include "object-store.h"
   8 #include "tag.h"
   9 #include "object.h"
  10 #include "commit.h"
  11 #include "diff.h"
  12 #include "revision.h"
  13 #include "list-objects.h"
  14 #include "list-objects-filter.h"
  15 #include "list-objects-filter-options.h"
  16 #include "run-command.h"
  17 #include "connect.h"
  18 #include "sigchain.h"
  19 #include "version.h"
  20 #include "string-list.h"
  21 #include "argv-array.h"
  22 #include "prio-queue.h"
  23 #include "protocol.h"
  24 #include "quote.h"
  25 #include "upload-pack.h"
  26 #include "serve.h"
  27 #include "commit-graph.h"
  28 #include "commit-reach.h"
  29 #include "shallow.h"
  30
  31 /* Remember to update object flag allocation in object.h */
  32 #define THEY_HAVE       (1u << 11)
  33 #define OUR_REF         (1u << 12)
  34 #define WANTED          (1u << 13)
  35 #define COMMON_KNOWN    (1u << 14)
  36
  37 #define SHALLOW         (1u << 16)
  38 #define NOT_SHALLOW     (1u << 17)
  39 #define CLIENT_SHALLOW  (1u << 18)
  40 #define HIDDEN_REF      (1u << 19)
  41
  42 #define ALL_FLAGS (THEY_HAVE | OUR_REF | WANTED | COMMON_KNOWN | SHALLOW | \
  43                 NOT_SHALLOW | CLIENT_SHALLOW | HIDDEN_REF)
  44
  45 /* Enum for allowed unadvertised object request (UOR) */
  46 enum allow_uor {
  47         /* Allow specifying sha1 if it is a ref tip. */
  48         ALLOW_TIP_SHA1 = 0x01,
  49         /* Allow request of a sha1 if it is reachable from a ref (possibly hidden ref). */
  50         ALLOW_REACHABLE_SHA1 = 0x02,
  51         /* Allow request of any sha1. Implies ALLOW_TIP_SHA1 and ALLOW_REACHABLE_SHA1. */
  52         ALLOW_ANY_SHA1 = 0x07
  53 };
  54
  55 /*
  56  * Please annotate, and if possible group together, fields used only
  57  * for protocol v0 or only for protocol v2.
  58  */
  59 struct upload_pack_data {
  60         struct string_list symref;                              /* v0 only */
  61         struct object_array want_obj;
  62         struct object_array have_obj;
  63         struct oid_array haves;                                 /* v2 only */
  64         struct string_list wanted_refs;                         /* v2 only */
  65
  66         struct object_array shallows;
  67         struct string_list deepen_not;
  68         struct object_array extra_edge_obj;
  69         int depth;
  70         timestamp_t deepen_since;
  71         int deepen_rev_list;
  72         int deepen_relative;
  73         int keepalive;
  74         int shallow_nr;
  75         timestamp_t oldest_have;
  76
  77         unsigned int timeout;                                   /* v0 only */
  78         enum {
  79                 NO_MULTI_ACK = 0,
  80                 MULTI_ACK = 1,
  81                 MULTI_ACK_DETAILED = 2
  82         } multi_ack;                                            /* v0 only */
  83
  84         /* 0 for no sideband, otherwise DEFAULT_PACKET_MAX or LARGE_PACKET_MAX */
  85         int use_sideband;
  86
  87         struct string_list uri_protocols;
  88         enum allow_uor allow_uor;
  89
  90         struct list_objects_filter_options filter_options;
  91
  92         struct packet_writer writer;
  93
  94         const char *pack_objects_hook;
  95
  96         unsigned stateless_rpc : 1;                             /* v0 only */
  97         unsigned no_done : 1;                                   /* v0 only */
  98         unsigned daemon_mode : 1;                               /* v0 only */
  99         unsigned filter_capability_requested : 1;               /* v0 only */
 100
 101         unsigned use_thin_pack : 1;
 102         unsigned use_ofs_delta : 1;
 103         unsigned no_progress : 1;
 104         unsigned use_include_tag : 1;
 105         unsigned allow_filter : 1;
 106
 107         unsigned done : 1;                                      /* v2 only */
 108         unsigned allow_ref_in_want : 1;                         /* v2 only */
 109         unsigned allow_sideband_all : 1;                        /* v2 only */
 110 };
 111
 112 static void upload_pack_data_init(struct upload_pack_data *data)
 113 {
 114         struct string_list symref = STRING_LIST_INIT_DUP;
 115         struct string_list wanted_refs = STRING_LIST_INIT_DUP;
 116         struct object_array want_obj = OBJECT_ARRAY_INIT;
 117         struct object_array have_obj = OBJECT_ARRAY_INIT;
 118         struct oid_array haves = OID_ARRAY_INIT;
 119         struct object_array shallows = OBJECT_ARRAY_INIT;
 120         struct string_list deepen_not = STRING_LIST_INIT_DUP;
 121         struct string_list uri_protocols = STRING_LIST_INIT_DUP;
 122         struct object_array extra_edge_obj = OBJECT_ARRAY_INIT;
 123
 124         memset(data, 0, sizeof(*data));
 125         data->symref = symref;
 126         data->wanted_refs = wanted_refs;
 127         data->want_obj = want_obj;
 128         data->have_obj = have_obj;
 129         data->haves = haves;
 130         data->shallows = shallows;
 131         data->deepen_not = deepen_not;
 132         data->uri_protocols = uri_protocols;
 133         data->extra_edge_obj = extra_edge_obj;
 134         packet_writer_init(&data->writer, 1);
 135
 136         data->keepalive = 5;
 137 }
 138
 139 static void upload_pack_data_clear(struct upload_pack_data *data)
 140 {
 141         string_list_clear(&data->symref, 1);
 142         string_list_clear(&data->wanted_refs, 1);
 143         object_array_clear(&data->want_obj);
 144         object_array_clear(&data->have_obj);
 145         oid_array_clear(&data->haves);
 146         object_array_clear(&data->shallows);
 147         string_list_clear(&data->deepen_not, 0);
 148         object_array_clear(&data->extra_edge_obj);
 149         list_objects_filter_release(&data->filter_options);
 150
 151         free((char *)data->pack_objects_hook);
 152 }
 153
 154 static void reset_timeout(unsigned int timeout)
 155 {
 156         alarm(timeout);
 157 }
 158
 159 static void send_client_data(int fd, const char *data, ssize_t sz,
 160                              int use_sideband)
 161 {
 162         if (use_sideband) {
 163                 send_sideband(1, fd, data, sz, use_sideband);
 164                 return;
 165         }
 166         if (fd == 3)
 167                 /* emergency quit */
 168                 fd = 2;
 169         if (fd == 2) {
 170                 /* XXX: are we happy to lose stuff here? */
 171                 xwrite(fd, data, sz);
 172                 return;
 173         }
 174         write_or_die(fd, data, sz);
 175 }
 176
 177 static int write_one_shallow(const struct commit_graft *graft, void *cb_data)
 178 {
 179         FILE *fp = cb_data;
 180         if (graft->nr_parent == -1)
 181                 fprintf(fp, "--shallow %s\n", oid_to_hex(&graft->oid));
 182         return 0;
 183 }
 184
 185 struct output_state {
 186         char buffer[8193];
 187         int used;
 188         unsigned packfile_uris_started : 1;
 189         unsigned packfile_started : 1;
 190 };
 191
 192 static int relay_pack_data(int pack_objects_out, struct output_state *os,
 193                            int use_sideband, int write_packfile_line)
 194 {
 195         /*
 196          * We keep the last byte to ourselves
 197          * in case we detect broken rev-list, so that we
 198          * can leave the stream corrupted.  This is
 199          * unfortunate -- unpack-objects would happily
 200          * accept a valid packdata with trailing garbage,
 201          * so appending garbage after we pass all the
 202          * pack data is not good enough to signal
 203          * breakage to downstream.
 204          */
 205         ssize_t readsz;
 206
 207         readsz = xread(pack_objects_out, os->buffer + os->used,
 208                        sizeof(os->buffer) - os->used);
 209         if (readsz < 0) {
 210                 return readsz;
 211         }
 212         os->used += readsz;
 213
 214         while (!os->packfile_started) {
 215                 char *p;
 216                 if (os->used >= 4 && !memcmp(os->buffer, "PACK", 4)) {
 217                         os->packfile_started = 1;
 218                         if (write_packfile_line) {
 219                                 if (os->packfile_uris_started)
 220                                         packet_delim(1);
 221                                 packet_write_fmt(1, "\1packfile\n");
 222                         }
 223                         break;
 224                 }
 225                 if ((p = memchr(os->buffer, '\n', os->used))) {
 226                         if (!os->packfile_uris_started) {
 227                                 os->packfile_uris_started = 1;
 228                                 if (!write_packfile_line)
 229                                         BUG("packfile_uris requires sideband-all");
 230                                 packet_write_fmt(1, "\1packfile-uris\n");
 231                         }
 232                         *p = '\0';
 233                         packet_write_fmt(1, "\1%s\n", os->buffer);
 234
 235                         os->used -= p - os->buffer + 1;
 236                         memmove(os->buffer, p + 1, os->used);
 237                 } else {
 238                         /*
 239                          * Incomplete line.
 240                          */
 241                         return readsz;
 242                 }
 243         }
 244
 245         if (os->used > 1) {
 246                 send_client_data(1, os->buffer, os->used - 1, use_sideband);
 247                 os->buffer[0] = os->buffer[os->used - 1];
 248                 os->used = 1;
 249         } else {
 250                 send_client_data(1, os->buffer, os->used, use_sideband);
 251                 os->used = 0;
 252         }
 253
 254         return readsz;
 255 }
 256
 257 static void create_pack_file(struct upload_pack_data *pack_data,
 258                              const struct string_list *uri_protocols)
 259 {
 260         struct child_process pack_objects = CHILD_PROCESS_INIT;
 261         struct output_state output_state = { { 0 } };
 262         char progress[128];
 263         char abort_msg[] = "aborting due to possible repository "
 264                 "corruption on the remote side.";
 265         ssize_t sz;
 266         int i;
 267         FILE *pipe_fd;
 268
 269         if (!pack_data->pack_objects_hook)
 270                 pack_objects.git_cmd = 1;
 271         else {
 272                 argv_array_push(&pack_objects.args, pack_data->pack_objects_hook);
 273                 argv_array_push(&pack_objects.args, "git");
 274                 pack_objects.use_shell = 1;
 275         }
 276
 277         if (pack_data->shallow_nr) {
 278                 argv_array_push(&pack_objects.args, "--shallow-file");
 279                 argv_array_push(&pack_objects.args, "");
 280         }
 281         argv_array_push(&pack_objects.args, "pack-objects");
 282         argv_array_push(&pack_objects.args, "--revs");
 283         if (pack_data->use_thin_pack)
 284                 argv_array_push(&pack_objects.args, "--thin");
 285
 286         argv_array_push(&pack_objects.args, "--stdout");
 287         if (pack_data->shallow_nr)
 288                 argv_array_push(&pack_objects.args, "--shallow");
 289         if (!pack_data->no_progress)
 290                 argv_array_push(&pack_objects.args, "--progress");
 291         if (pack_data->use_ofs_delta)
 292                 argv_array_push(&pack_objects.args, "--delta-base-offset");
 293         if (pack_data->use_include_tag)
 294                 argv_array_push(&pack_objects.args, "--include-tag");
 295         if (pack_data->filter_options.choice) {
 296                 const char *spec =
 297                         expand_list_objects_filter_spec(&pack_data->filter_options);
 298                 if (pack_objects.use_shell) {
 299                         struct strbuf buf = STRBUF_INIT;
 300                         sq_quote_buf(&buf, spec);
 301                         argv_array_pushf(&pack_objects.args, "--filter=%s", buf.buf);
 302                         strbuf_release(&buf);
 303                 } else {
 304                         argv_array_pushf(&pack_objects.args, "--filter=%s",
 305                                          spec);
 306                 }
 307         }
 308         if (uri_protocols) {
 309                 for (i = 0; i < uri_protocols->nr; i++)
 310                         argv_array_pushf(&pack_objects.args, "--uri-protocol=%s",
 311                                          uri_protocols->items[i].string);
 312         }
 313
 314         pack_objects.in = -1;
 315         pack_objects.out = -1;
 316         pack_objects.err = -1;
 317
 318         if (start_command(&pack_objects))
 319                 die("git upload-pack: unable to fork git-pack-objects");
 320
 321         pipe_fd = xfdopen(pack_objects.in, "w");
 322
 323         if (pack_data->shallow_nr)
 324                 for_each_commit_graft(write_one_shallow, pipe_fd);
 325
 326         for (i = 0; i < pack_data->want_obj.nr; i++)
 327                 fprintf(pipe_fd, "%s\n",
 328                         oid_to_hex(&pack_data->want_obj.objects[i].item->oid));
 329         fprintf(pipe_fd, "--not\n");
 330         for (i = 0; i < pack_data->have_obj.nr; i++)
 331                 fprintf(pipe_fd, "%s\n",
 332                         oid_to_hex(&pack_data->have_obj.objects[i].item->oid));
 333         for (i = 0; i < pack_data->extra_edge_obj.nr; i++)
 334                 fprintf(pipe_fd, "%s\n",
 335                         oid_to_hex(&pack_data->extra_edge_obj.objects[i].item->oid));
 336         fprintf(pipe_fd, "\n");
 337         fflush(pipe_fd);
 338         fclose(pipe_fd);
 339
 340         /* We read from pack_objects.err to capture stderr output for
 341          * progress bar, and pack_objects.out to capture the pack data.
 342          */
 343
 344         while (1) {
 345                 struct pollfd pfd[2];
 346                 int pe, pu, pollsize, polltimeout;
 347                 int ret;
 348
 349                 reset_timeout(pack_data->timeout);
 350
 351                 pollsize = 0;
 352                 pe = pu = -1;
 353
 354                 if (0 <= pack_objects.out) {
 355                         pfd[pollsize].fd = pack_objects.out;
 356                         pfd[pollsize].events = POLLIN;
 357                         pu = pollsize;
 358                         pollsize++;
 359                 }
 360                 if (0 <= pack_objects.err) {
 361                         pfd[pollsize].fd = pack_objects.err;
 362                         pfd[pollsize].events = POLLIN;
 363                         pe = pollsize;
 364                         pollsize++;
 365                 }
 366
 367                 if (!pollsize)
 368                         break;
 369
 370                 polltimeout = pack_data->keepalive < 0
 371                         ? -1
 372                         : 1000 * pack_data->keepalive;
 373
 374                 ret = poll(pfd, pollsize, polltimeout);
 375
 376                 if (ret < 0) {
 377                         if (errno != EINTR) {
 378                                 error_errno("poll failed, resuming");
 379                                 sleep(1);
 380                         }
 381                         continue;
 382                 }
 383                 if (0 <= pe && (pfd[pe].revents & (POLLIN|POLLHUP))) {
 384                         /* Status ready; we ship that in the side-band
 385                          * or dump to the standard error.
 386                          */
 387                         sz = xread(pack_objects.err, progress,
 388                                   sizeof(progress));
 389                         if (0 < sz)
 390                                 send_client_data(2, progress, sz,
 391                                                  pack_data->use_sideband);
 392                         else if (sz == 0) {
 393                                 close(pack_objects.err);
 394                                 pack_objects.err = -1;
 395                         }
 396                         else
 397                                 goto fail;
 398                         /* give priority to status messages */
 399                         continue;
 400                 }
 401                 if (0 <= pu && (pfd[pu].revents & (POLLIN|POLLHUP))) {
 402                         int result = relay_pack_data(pack_objects.out,
 403                                                      &output_state,
 404                                                      pack_data->use_sideband,
 405                                                      !!uri_protocols);
 406
 407                         if (result == 0) {
 408                                 close(pack_objects.out);
 409                                 pack_objects.out = -1;
 410                         } else if (result < 0) {
 411                                 goto fail;
 412                         }
 413                 }
 414
 415                 /*
 416                  * We hit the keepalive timeout without saying anything; send
 417                  * an empty message on the data sideband just to let the other
 418                  * side know we're still working on it, but don't have any data
 419                  * yet.
 420                  *
 421                  * If we don't have a sideband channel, there's no room in the
 422                  * protocol to say anything, so those clients are just out of
 423                  * luck.
 424                  */
 425                 if (!ret && pack_data->use_sideband) {
 426                         static const char buf[] = "0005\1";
 427                         write_or_die(1, buf, 5);
 428                 }
 429         }
 430
 431         if (finish_command(&pack_objects)) {
 432                 error("git upload-pack: git-pack-objects died with error.");
 433                 goto fail;
 434         }
 435
 436         /* flush the data */
 437         if (output_state.used > 0) {
 438                 send_client_data(1, output_state.buffer, output_state.used,
 439                                  pack_data->use_sideband);
 440                 fprintf(stderr, "flushed.\n");
 441         }
 442         if (pack_data->use_sideband)
 443                 packet_flush(1);
 444         return;
 445
 446  fail:
 447         send_client_data(3, abort_msg, sizeof(abort_msg),
 448                          pack_data->use_sideband);
 449         die("git upload-pack: %s", abort_msg);
 450 }
 451
 452 static int do_got_oid(struct upload_pack_data *data, const struct object_id *oid)
 453 {
 454         int we_knew_they_have = 0;
 455         struct object *o = parse_object(the_repository, oid);
 456
 457         if (!o)
 458                 die("oops (%s)", oid_to_hex(oid));
 459         if (o->type == OBJ_COMMIT) {
 460                 struct commit_list *parents;
 461                 struct commit *commit = (struct commit *)o;
 462                 if (o->flags & THEY_HAVE)
 463                         we_knew_they_have = 1;
 464                 else
 465                         o->flags |= THEY_HAVE;
 466                 if (!data->oldest_have || (commit->date < data->oldest_have))
 467                         data->oldest_have = commit->date;
 468                 for (parents = commit->parents;
 469                      parents;
 470                      parents = parents->next)
 471                         parents->item->object.flags |= THEY_HAVE;
 472         }
 473         if (!we_knew_they_have) {
 474                 add_object_array(o, NULL, &data->have_obj);
 475                 return 1;
 476         }
 477         return 0;
 478 }
 479
 480 static int got_oid(struct upload_pack_data *data,
 481                    const char *hex, struct object_id *oid)
 482 {
 483         if (get_oid_hex(hex, oid))
 484                 die("git upload-pack: expected SHA1 object, got '%s'", hex);
 485         if (!has_object_file_with_flags(oid,
 486                                         OBJECT_INFO_QUICK | OBJECT_INFO_SKIP_FETCH_OBJECT))
 487                 return -1;
 488         return do_got_oid(data, oid);
 489 }
 490
 491 static int ok_to_give_up(struct upload_pack_data *data)
 492 {
 493         uint32_t min_generation = GENERATION_NUMBER_ZERO;
 494
 495         if (!data->have_obj.nr)
 496                 return 0;
 497
 498         return can_all_from_reach_with_flag(&data->want_obj, THEY_HAVE,
 499                                             COMMON_KNOWN, data->oldest_have,
 500                                             min_generation);
 501 }
 502
 503 static int get_common_commits(struct upload_pack_data *data,
 504                               struct packet_reader *reader)
 505 {
 506         struct object_id oid;
 507         char last_hex[GIT_MAX_HEXSZ + 1];
 508         int got_common = 0;
 509         int got_other = 0;
 510         int sent_ready = 0;
 511
 512         save_commit_buffer = 0;
 513
 514         for (;;) {
 515                 const char *arg;
 516
 517                 reset_timeout(data->timeout);
 518
 519                 if (packet_reader_read(reader) != PACKET_READ_NORMAL) {
 520                         if (data->multi_ack == MULTI_ACK_DETAILED
 521                             && got_common
 522                             && !got_other
 523                             && ok_to_give_up(data)) {
 524                                 sent_ready = 1;
 525                                 packet_write_fmt(1, "ACK %s ready\n", last_hex);
 526                         }
 527                         if (data->have_obj.nr == 0 || data->multi_ack)
 528                                 packet_write_fmt(1, "NAK\n");
 529
 530                         if (data->no_done && sent_ready) {
 531                                 packet_write_fmt(1, "ACK %s\n", last_hex);
 532                                 return 0;
 533                         }
 534                         if (data->stateless_rpc)
 535                                 exit(0);
 536                         got_common = 0;
 537                         got_other = 0;
 538                         continue;
 539                 }
 540                 if (skip_prefix(reader->line, "have ", &arg)) {
 541                         switch (got_oid(data, arg, &oid)) {
 542                         case -1: /* they have what we do not */
 543                                 got_other = 1;
 544                                 if (data->multi_ack
 545                                     && ok_to_give_up(data)) {
 546                                         const char *hex = oid_to_hex(&oid);
 547                                         if (data->multi_ack == MULTI_ACK_DETAILED) {
 548                                                 sent_ready = 1;
 549                                                 packet_write_fmt(1, "ACK %s ready\n", hex);
 550                                         } else
 551                                                 packet_write_fmt(1, "ACK %s continue\n", hex);
 552                                 }
 553                                 break;
 554                         default:
 555                                 got_common = 1;
 556                                 oid_to_hex_r(last_hex, &oid);
 557                                 if (data->multi_ack == MULTI_ACK_DETAILED)
 558                                         packet_write_fmt(1, "ACK %s common\n", last_hex);
 559                                 else if (data->multi_ack)
 560                                         packet_write_fmt(1, "ACK %s continue\n", last_hex);
 561                                 else if (data->have_obj.nr == 1)
 562                                         packet_write_fmt(1, "ACK %s\n", last_hex);
 563                                 break;
 564                         }
 565                         continue;
 566                 }
 567                 if (!strcmp(reader->line, "done")) {
 568                         if (data->have_obj.nr > 0) {
 569                                 if (data->multi_ack)
 570                                         packet_write_fmt(1, "ACK %s\n", last_hex);
 571                                 return 0;
 572                         }
 573                         packet_write_fmt(1, "NAK\n");
 574                         return -1;
 575                 }
 576                 die("git upload-pack: expected SHA1 list, got '%s'", reader->line);
 577         }
 578 }
 579
 580 static int is_our_ref(struct object *o, enum allow_uor allow_uor)
 581 {
 582         int allow_hidden_ref = (allow_uor &
 583                                 (ALLOW_TIP_SHA1 | ALLOW_REACHABLE_SHA1));
 584         return o->flags & ((allow_hidden_ref ? HIDDEN_REF : 0) | OUR_REF);
 585 }
 586
 587 /*
 588  * on successful case, it's up to the caller to close cmd->out
 589  */
 590 static int do_reachable_revlist(struct child_process *cmd,
 591                                 struct object_array *src,
 592                                 struct object_array *reachable,
 593                                 enum allow_uor allow_uor)
 594 {
 595         static const char *argv[] = {
 596                 "rev-list", "--stdin", NULL,
 597         };
 598         struct object *o;
 599         char namebuf[GIT_MAX_HEXSZ + 2]; /* ^ + hash + LF */
 600         int i;
 601         const unsigned hexsz = the_hash_algo->hexsz;
 602
 603         cmd->argv = argv;
 604         cmd->git_cmd = 1;
 605         cmd->no_stderr = 1;
 606         cmd->in = -1;
 607         cmd->out = -1;
 608
 609         /*
 610          * If the next rev-list --stdin encounters an unknown commit,
 611          * it terminates, which will cause SIGPIPE in the write loop
 612          * below.
 613          */
 614         sigchain_push(SIGPIPE, SIG_IGN);
 615
 616         if (start_command(cmd))
 617                 goto error;
 618
 619         namebuf[0] = '^';
 620         namebuf[hexsz + 1] = '\n';
 621         for (i = get_max_object_index(); 0 < i; ) {
 622                 o = get_indexed_object(--i);
 623                 if (!o)
 624                         continue;
 625                 if (reachable && o->type == OBJ_COMMIT)
 626                         o->flags &= ~TMP_MARK;
 627                 if (!is_our_ref(o, allow_uor))
 628                         continue;
 629                 memcpy(namebuf + 1, oid_to_hex(&o->oid), hexsz);
 630                 if (write_in_full(cmd->in, namebuf, hexsz + 2) < 0)
 631                         goto error;
 632         }
 633         namebuf[hexsz] = '\n';
 634         for (i = 0; i < src->nr; i++) {
 635                 o = src->objects[i].item;
 636                 if (is_our_ref(o, allow_uor)) {
 637                         if (reachable)
 638                                 add_object_array(o, NULL, reachable);
 639                         continue;
 640                 }
 641                 if (reachable && o->type == OBJ_COMMIT)
 642                         o->flags |= TMP_MARK;
 643                 memcpy(namebuf, oid_to_hex(&o->oid), hexsz);
 644                 if (write_in_full(cmd->in, namebuf, hexsz + 1) < 0)
 645                         goto error;
 646         }
 647         close(cmd->in);
 648         cmd->in = -1;
 649         sigchain_pop(SIGPIPE);
 650
 651         return 0;
 652
 653 error:
 654         sigchain_pop(SIGPIPE);
 655
 656         if (cmd->in >= 0)
 657                 close(cmd->in);
 658         if (cmd->out >= 0)
 659                 close(cmd->out);
 660         return -1;
 661 }
 662
 663 static int get_reachable_list(struct upload_pack_data *data,
 664                               struct object_array *reachable)
 665 {
 666         struct child_process cmd = CHILD_PROCESS_INIT;
 667         int i;
 668         struct object *o;
 669         char namebuf[GIT_MAX_HEXSZ + 2]; /* ^ + hash + LF */
 670         const unsigned hexsz = the_hash_algo->hexsz;
 671
 672         if (do_reachable_revlist(&cmd, &data->shallows, reachable,
 673                                  data->allow_uor) < 0)
 674                 return -1;
 675
 676         while ((i = read_in_full(cmd.out, namebuf, hexsz + 1)) == hexsz + 1) {
 677                 struct object_id oid;
 678                 const char *p;
 679
 680                 if (parse_oid_hex(namebuf, &oid, &p) || *p != '\n')
 681                         break;
 682
 683                 o = lookup_object(the_repository, &oid);
 684                 if (o && o->type == OBJ_COMMIT) {
 685                         o->flags &= ~TMP_MARK;
 686                 }
 687         }
 688         for (i = get_max_object_index(); 0 < i; i--) {
 689                 o = get_indexed_object(i - 1);
 690                 if (o && o->type == OBJ_COMMIT &&
 691                     (o->flags & TMP_MARK)) {
 692                         add_object_array(o, NULL, reachable);
 693                                 o->flags &= ~TMP_MARK;
 694                 }
 695         }
 696         close(cmd.out);
 697
 698         if (finish_command(&cmd))
 699                 return -1;
 700
 701         return 0;
 702 }
 703
 704 static int has_unreachable(struct object_array *src, enum allow_uor allow_uor)
 705 {
 706         struct child_process cmd = CHILD_PROCESS_INIT;
 707         char buf[1];
 708         int i;
 709
 710         if (do_reachable_revlist(&cmd, src, NULL, allow_uor) < 0)
 711                 return 1;
 712
 713         /*
 714          * The commits out of the rev-list are not ancestors of
 715          * our ref.
 716          */
 717         i = read_in_full(cmd.out, buf, 1);
 718         if (i)
 719                 goto error;
 720         close(cmd.out);
 721         cmd.out = -1;
 722
 723         /*
 724          * rev-list may have died by encountering a bad commit
 725          * in the history, in which case we do want to bail out
 726          * even when it showed no commit.
 727          */
 728         if (finish_command(&cmd))
 729                 goto error;
 730
 731         /* All the non-tip ones are ancestors of what we advertised */
 732         return 0;
 733
 734 error:
 735         sigchain_pop(SIGPIPE);
 736         if (cmd.out >= 0)
 737                 close(cmd.out);
 738         return 1;
 739 }
 740
 741 static void check_non_tip(struct upload_pack_data *data)
 742 {
 743         int i;
 744
 745         /*
 746          * In the normal in-process case without
 747          * uploadpack.allowReachableSHA1InWant,
 748          * non-tip requests can never happen.
 749          */
 750         if (!data->stateless_rpc && !(data->allow_uor & ALLOW_REACHABLE_SHA1))
 751                 goto error;
 752         if (!has_unreachable(&data->want_obj, data->allow_uor))
 753                 /* All the non-tip ones are ancestors of what we advertised */
 754                 return;
 755
 756 error:
 757         /* Pick one of them (we know there at least is one) */
 758         for (i = 0; i < data->want_obj.nr; i++) {
 759                 struct object *o = data->want_obj.objects[i].item;
 760                 if (!is_our_ref(o, data->allow_uor)) {
 761                         packet_writer_error(&data->writer,
 762                                             "upload-pack: not our ref %s",
 763                                             oid_to_hex(&o->oid));
 764                         die("git upload-pack: not our ref %s",
 765                             oid_to_hex(&o->oid));
 766                 }
 767         }
 768 }
 769
 770 static void send_shallow(struct upload_pack_data *data,
 771                          struct commit_list *result)
 772 {
 773         while (result) {
 774                 struct object *object = &result->item->object;
 775                 if (!(object->flags & (CLIENT_SHALLOW|NOT_SHALLOW))) {
 776                         packet_writer_write(&data->writer, "shallow %s",
 777                                             oid_to_hex(&object->oid));
 778                         register_shallow(the_repository, &object->oid);
 779                         data->shallow_nr++;
 780                 }
 781                 result = result->next;
 782         }
 783 }
 784
 785 static void send_unshallow(struct upload_pack_data *data)
 786 {
 787         int i;
 788
 789         for (i = 0; i < data->shallows.nr; i++) {
 790                 struct object *object = data->shallows.objects[i].item;
 791                 if (object->flags & NOT_SHALLOW) {
 792                         struct commit_list *parents;
 793                         packet_writer_write(&data->writer, "unshallow %s",
 794                                             oid_to_hex(&object->oid));
 795                         object->flags &= ~CLIENT_SHALLOW;
 796                         /*
 797                          * We want to _register_ "object" as shallow, but we
 798                          * also need to traverse object's parents to deepen a
 799                          * shallow clone. Unregister it for now so we can
 800                          * parse and add the parents to the want list, then
 801                          * re-register it.
 802                          */
 803                         unregister_shallow(&object->oid);
 804                         object->parsed = 0;
 805                         parse_commit_or_die((struct commit *)object);
 806                         parents = ((struct commit *)object)->parents;
 807                         while (parents) {
 808                                 add_object_array(&parents->item->object,
 809                                                  NULL, &data->want_obj);
 810                                 parents = parents->next;
 811                         }
 812                         add_object_array(object, NULL, &data->extra_edge_obj);
 813                 }
 814                 /* make sure commit traversal conforms to client */
 815                 register_shallow(the_repository, &object->oid);
 816         }
 817 }
 818
 819 static int check_ref(const char *refname_full, const struct object_id *oid,
 820                      int flag, void *cb_data);
 821 static void deepen(struct upload_pack_data *data, int depth)
 822 {
 823         if (depth == INFINITE_DEPTH && !is_repository_shallow(the_repository)) {
 824                 int i;
 825
 826                 for (i = 0; i < data->shallows.nr; i++) {
 827                         struct object *object = data->shallows.objects[i].item;
 828                         object->flags |= NOT_SHALLOW;
 829                 }
 830         } else if (data->deepen_relative) {
 831                 struct object_array reachable_shallows = OBJECT_ARRAY_INIT;
 832                 struct commit_list *result;
 833
 834                 /*
 835                  * Checking for reachable shallows requires that our refs be
 836                  * marked with OUR_REF.
 837                  */
 838                 head_ref_namespaced(check_ref, NULL);
 839                 for_each_namespaced_ref(check_ref, NULL);
 840
 841                 get_reachable_list(data, &reachable_shallows);
 842                 result = get_shallow_commits(&reachable_shallows,
 843                                              depth + 1,
 844                                              SHALLOW, NOT_SHALLOW);
 845                 send_shallow(data, result);
 846                 free_commit_list(result);
 847                 object_array_clear(&reachable_shallows);
 848         } else {
 849                 struct commit_list *result;
 850
 851                 result = get_shallow_commits(&data->want_obj, depth,
 852                                              SHALLOW, NOT_SHALLOW);
 853                 send_shallow(data, result);
 854                 free_commit_list(result);
 855         }
 856
 857         send_unshallow(data);
 858 }
 859
 860 static void deepen_by_rev_list(struct upload_pack_data *data,
 861                                int ac,
 862                                const char **av)
 863 {
 864         struct commit_list *result;
 865
 866         disable_commit_graph(the_repository);
 867         result = get_shallow_commits_by_rev_list(ac, av, SHALLOW, NOT_SHALLOW);
 868         send_shallow(data, result);
 869         free_commit_list(result);
 870         send_unshallow(data);
 871 }
 872
 873 /* Returns 1 if a shallow list is sent or 0 otherwise */
 874 static int send_shallow_list(struct upload_pack_data *data)
 875 {
 876         int ret = 0;
 877
 878         if (data->depth > 0 && data->deepen_rev_list)
 879                 die("git upload-pack: deepen and deepen-since (or deepen-not) cannot be used together");
 880         if (data->depth > 0) {
 881                 deepen(data, data->depth);
 882                 ret = 1;
 883         } else if (data->deepen_rev_list) {
 884                 struct argv_array av = ARGV_ARRAY_INIT;
 885                 int i;
 886
 887                 argv_array_push(&av, "rev-list");
 888                 if (data->deepen_since)
 889                         argv_array_pushf(&av, "--max-age=%"PRItime, data->deepen_since);
 890                 if (data->deepen_not.nr) {
 891                         argv_array_push(&av, "--not");
 892                         for (i = 0; i < data->deepen_not.nr; i++) {
 893                                 struct string_list_item *s = data->deepen_not.items + i;
 894                                 argv_array_push(&av, s->string);
 895                         }
 896                         argv_array_push(&av, "--not");
 897                 }
 898                 for (i = 0; i < data->want_obj.nr; i++) {
 899                         struct object *o = data->want_obj.objects[i].item;
 900                         argv_array_push(&av, oid_to_hex(&o->oid));
 901                 }
 902                 deepen_by_rev_list(data, av.argc, av.argv);
 903                 argv_array_clear(&av);
 904                 ret = 1;
 905         } else {
 906                 if (data->shallows.nr > 0) {
 907                         int i;
 908                         for (i = 0; i < data->shallows.nr; i++)
 909                                 register_shallow(the_repository,
 910                                                  &data->shallows.objects[i].item->oid);
 911                 }
 912         }
 913
 914         data->shallow_nr += data->shallows.nr;
 915         return ret;
 916 }
 917
 918 static int process_shallow(const char *line, struct object_array *shallows)
 919 {
 920         const char *arg;
 921         if (skip_prefix(line, "shallow ", &arg)) {
 922                 struct object_id oid;
 923                 struct object *object;
 924                 if (get_oid_hex(arg, &oid))
 925                         die("invalid shallow line: %s", line);
 926                 object = parse_object(the_repository, &oid);
 927                 if (!object)
 928                         return 1;
 929                 if (object->type != OBJ_COMMIT)
 930                         die("invalid shallow object %s", oid_to_hex(&oid));
 931                 if (!(object->flags & CLIENT_SHALLOW)) {
 932                         object->flags |= CLIENT_SHALLOW;
 933                         add_object_array(object, NULL, shallows);
 934                 }
 935                 return 1;
 936         }
 937
 938         return 0;
 939 }
 940
 941 static int process_deepen(const char *line, int *depth)
 942 {
 943         const char *arg;
 944         if (skip_prefix(line, "deepen ", &arg)) {
 945                 char *end = NULL;
 946                 *depth = (int)strtol(arg, &end, 0);
 947                 if (!end || *end || *depth <= 0)
 948                         die("Invalid deepen: %s", line);
 949                 return 1;
 950         }
 951
 952         return 0;
 953 }
 954
 955 static int process_deepen_since(const char *line, timestamp_t *deepen_since, int *deepen_rev_list)
 956 {
 957         const char *arg;
 958         if (skip_prefix(line, "deepen-since ", &arg)) {
 959                 char *end = NULL;
 960                 *deepen_since = parse_timestamp(arg, &end, 0);
 961                 if (!end || *end || !deepen_since ||
 962                     /* revisions.c's max_age -1 is special */
 963                     *deepen_since == -1)
 964                         die("Invalid deepen-since: %s", line);
 965                 *deepen_rev_list = 1;
 966                 return 1;
 967         }
 968         return 0;
 969 }
 970
 971 static int process_deepen_not(const char *line, struct string_list *deepen_not, int *deepen_rev_list)
 972 {
 973         const char *arg;
 974         if (skip_prefix(line, "deepen-not ", &arg)) {
 975                 char *ref = NULL;
 976                 struct object_id oid;
 977                 if (expand_ref(the_repository, arg, strlen(arg), &oid, &ref) != 1)
 978                         die("git upload-pack: ambiguous deepen-not: %s", line);
 979                 string_list_append(deepen_not, ref);
 980                 free(ref);
 981                 *deepen_rev_list = 1;
 982                 return 1;
 983         }
 984         return 0;
 985 }
 986
 987 static void receive_needs(struct upload_pack_data *data,
 988                           struct packet_reader *reader)
 989 {
 990         int has_non_tip = 0;
 991
 992         data->shallow_nr = 0;
 993         for (;;) {
 994                 struct object *o;
 995                 const char *features;
 996                 struct object_id oid_buf;
 997                 const char *arg;
 998
 999                 reset_timeout(data->timeout);
1000                 if (packet_reader_read(reader) != PACKET_READ_NORMAL)
1001                         break;
1002
1003                 if (process_shallow(reader->line, &data->shallows))
1004                         continue;
1005                 if (process_deepen(reader->line, &data->depth))
1006                         continue;
1007                 if (process_deepen_since(reader->line, &data->deepen_since, &data->deepen_rev_list))
1008                         continue;
1009                 if (process_deepen_not(reader->line, &data->deepen_not, &data->deepen_rev_list))
1010                         continue;
1011
1012                 if (skip_prefix(reader->line, "filter ", &arg)) {
1013                         if (!data->filter_capability_requested)
1014                                 die("git upload-pack: filtering capability not negotiated");
1015                         list_objects_filter_die_if_populated(&data->filter_options);
1016                         parse_list_objects_filter(&data->filter_options, arg);
1017                         continue;
1018                 }
1019
1020                 if (!skip_prefix(reader->line, "want ", &arg) ||
1021                     parse_oid_hex(arg, &oid_buf, &features))
1022                         die("git upload-pack: protocol error, "
1023                             "expected to get object ID, not '%s'", reader->line);
1024
1025                 if (parse_feature_request(features, "deepen-relative"))
1026                         data->deepen_relative = 1;
1027                 if (parse_feature_request(features, "multi_ack_detailed"))
1028                         data->multi_ack = MULTI_ACK_DETAILED;
1029                 else if (parse_feature_request(features, "multi_ack"))
1030                         data->multi_ack = MULTI_ACK;
1031                 if (parse_feature_request(features, "no-done"))
1032                         data->no_done = 1;
1033                 if (parse_feature_request(features, "thin-pack"))
1034                         data->use_thin_pack = 1;
1035                 if (parse_feature_request(features, "ofs-delta"))
1036                         data->use_ofs_delta = 1;
1037                 if (parse_feature_request(features, "side-band-64k"))
1038                         data->use_sideband = LARGE_PACKET_MAX;
1039                 else if (parse_feature_request(features, "side-band"))
1040                         data->use_sideband = DEFAULT_PACKET_MAX;
1041                 if (parse_feature_request(features, "no-progress"))
1042                         data->no_progress = 1;
1043                 if (parse_feature_request(features, "include-tag"))
1044                         data->use_include_tag = 1;
1045                 if (data->allow_filter &&
1046                     parse_feature_request(features, "filter"))
1047                         data->filter_capability_requested = 1;
1048
1049                 o = parse_object(the_repository, &oid_buf);
1050                 if (!o) {
1051                         packet_writer_error(&data->writer,
1052                                             "upload-pack: not our ref %s",
1053                                             oid_to_hex(&oid_buf));
1054                         die("git upload-pack: not our ref %s",
1055                             oid_to_hex(&oid_buf));
1056                 }
1057                 if (!(o->flags & WANTED)) {
1058                         o->flags |= WANTED;
1059                         if (!((data->allow_uor & ALLOW_ANY_SHA1) == ALLOW_ANY_SHA1
1060                               || is_our_ref(o, data->allow_uor)))
1061                                 has_non_tip = 1;
1062                         add_object_array(o, NULL, &data->want_obj);
1063                 }
1064         }
1065
1066         /*
1067          * We have sent all our refs already, and the other end
1068          * should have chosen out of them. When we are operating
1069          * in the stateless RPC mode, however, their choice may
1070          * have been based on the set of older refs advertised
1071          * by another process that handled the initial request.
1072          */
1073         if (has_non_tip)
1074                 check_non_tip(data);
1075
1076         if (!data->use_sideband && data->daemon_mode)
1077                 data->no_progress = 1;
1078
1079         if (data->depth == 0 && !data->deepen_rev_list && data->shallows.nr == 0)
1080                 return;
1081
1082         if (send_shallow_list(data))
1083                 packet_flush(1);
1084 }
1085
1086 /* return non-zero if the ref is hidden, otherwise 0 */
1087 static int mark_our_ref(const char *refname, const char *refname_full,
1088                         const struct object_id *oid)
1089 {
1090         struct object *o = lookup_unknown_object(oid);
1091
1092         if (ref_is_hidden(refname, refname_full)) {
1093                 o->flags |= HIDDEN_REF;
1094                 return 1;
1095         }
1096         o->flags |= OUR_REF;
1097         return 0;
1098 }
1099
1100 static int check_ref(const char *refname_full, const struct object_id *oid,
1101                      int flag, void *cb_data)
1102 {
1103         const char *refname = strip_namespace(refname_full);
1104
1105         mark_our_ref(refname, refname_full, oid);
1106         return 0;
1107 }
1108
1109 static void format_symref_info(struct strbuf *buf, struct string_list *symref)
1110 {
1111         struct string_list_item *item;
1112
1113         if (!symref->nr)
1114                 return;
1115         for_each_string_list_item(item, symref)
1116                 strbuf_addf(buf, " symref=%s:%s", item->string, (char *)item->util);
1117 }
1118
1119 static int send_ref(const char *refname, const struct object_id *oid,
1120                     int flag, void *cb_data)
1121 {
1122         static const char *capabilities = "multi_ack thin-pack side-band"
1123                 " side-band-64k ofs-delta shallow deepen-since deepen-not"
1124                 " deepen-relative no-progress include-tag multi_ack_detailed";
1125         const char *refname_nons = strip_namespace(refname);
1126         struct object_id peeled;
1127         struct upload_pack_data *data = cb_data;
1128
1129         if (mark_our_ref(refname_nons, refname, oid))
1130                 return 0;
1131
1132         if (capabilities) {
1133                 struct strbuf symref_info = STRBUF_INIT;
1134
1135                 format_symref_info(&symref_info, &data->symref);
1136                 packet_write_fmt(1, "%s %s%c%s%s%s%s%s%s object-format=%s agent=%s\n",
1137                              oid_to_hex(oid), refname_nons,
1138                              0, capabilities,
1139                              (data->allow_uor & ALLOW_TIP_SHA1) ?
1140                                      " allow-tip-sha1-in-want" : "",
1141                              (data->allow_uor & ALLOW_REACHABLE_SHA1) ?
1142                                      " allow-reachable-sha1-in-want" : "",
1143                              data->stateless_rpc ? " no-done" : "",
1144                              symref_info.buf,
1145                              data->allow_filter ? " filter" : "",
1146                              the_hash_algo->name,
1147                              git_user_agent_sanitized());
1148                 strbuf_release(&symref_info);
1149         } else {
1150                 packet_write_fmt(1, "%s %s\n", oid_to_hex(oid), refname_nons);
1151         }
1152         capabilities = NULL;
1153         if (!peel_ref(refname, &peeled))
1154                 packet_write_fmt(1, "%s %s^{}\n", oid_to_hex(&peeled), refname_nons);
1155         return 0;
1156 }
1157
1158 static int find_symref(const char *refname, const struct object_id *oid,
1159                        int flag, void *cb_data)
1160 {
1161         const char *symref_target;
1162         struct string_list_item *item;
1163
1164         if ((flag & REF_ISSYMREF) == 0)
1165                 return 0;
1166         symref_target = resolve_ref_unsafe(refname, 0, NULL, &flag);
1167         if (!symref_target || (flag & REF_ISSYMREF) == 0)
1168                 die("'%s' is a symref but it is not?", refname);
1169         item = string_list_append(cb_data, strip_namespace(refname));
1170         item->util = xstrdup(strip_namespace(symref_target));
1171         return 0;
1172 }
1173
1174 static int upload_pack_config(const char *var, const char *value, void *cb_data)
1175 {
1176         struct upload_pack_data *data = cb_data;
1177
1178         if (!strcmp("uploadpack.allowtipsha1inwant", var)) {
1179                 if (git_config_bool(var, value))
1180                         data->allow_uor |= ALLOW_TIP_SHA1;
1181                 else
1182                         data->allow_uor &= ~ALLOW_TIP_SHA1;
1183         } else if (!strcmp("uploadpack.allowreachablesha1inwant", var)) {
1184                 if (git_config_bool(var, value))
1185                         data->allow_uor |= ALLOW_REACHABLE_SHA1;
1186                 else
1187                         data->allow_uor &= ~ALLOW_REACHABLE_SHA1;
1188         } else if (!strcmp("uploadpack.allowanysha1inwant", var)) {
1189                 if (git_config_bool(var, value))
1190                         data->allow_uor |= ALLOW_ANY_SHA1;
1191                 else
1192                         data->allow_uor &= ~ALLOW_ANY_SHA1;
1193         } else if (!strcmp("uploadpack.keepalive", var)) {
1194                 data->keepalive = git_config_int(var, value);
1195                 if (!data->keepalive)
1196                         data->keepalive = -1;
1197         } else if (!strcmp("uploadpack.allowfilter", var)) {
1198                 data->allow_filter = git_config_bool(var, value);
1199         } else if (!strcmp("uploadpack.allowrefinwant", var)) {
1200                 data->allow_ref_in_want = git_config_bool(var, value);
1201         } else if (!strcmp("uploadpack.allowsidebandall", var)) {
1202                 data->allow_sideband_all = git_config_bool(var, value);
1203         } else if (!strcmp("core.precomposeunicode", var)) {
1204                 precomposed_unicode = git_config_bool(var, value);
1205         }
1206
1207         if (current_config_scope() != CONFIG_SCOPE_LOCAL &&
1208         current_config_scope() != CONFIG_SCOPE_WORKTREE) {
1209                 if (!strcmp("uploadpack.packobjectshook", var))
1210                         return git_config_string(&data->pack_objects_hook, var, value);
1211         }
1212
1213         return parse_hide_refs_config(var, value, "uploadpack");
1214 }
1215
1216 void upload_pack(struct upload_pack_options *options)
1217 {
1218         struct packet_reader reader;
1219         struct upload_pack_data data;
1220
1221         upload_pack_data_init(&data);
1222
1223         git_config(upload_pack_config, &data);
1224
1225         data.stateless_rpc = options->stateless_rpc;
1226         data.daemon_mode = options->daemon_mode;
1227         data.timeout = options->timeout;
1228
1229         head_ref_namespaced(find_symref, &data.symref);
1230
1231         if (options->advertise_refs || !data.stateless_rpc) {
1232                 reset_timeout(data.timeout);
1233                 head_ref_namespaced(send_ref, &data);
1234                 for_each_namespaced_ref(send_ref, &data);
1235                 advertise_shallow_grafts(1);
1236                 packet_flush(1);
1237         } else {
1238                 head_ref_namespaced(check_ref, NULL);
1239                 for_each_namespaced_ref(check_ref, NULL);
1240         }
1241
1242         if (!options->advertise_refs) {
1243                 packet_reader_init(&reader, 0, NULL, 0,
1244                                    PACKET_READ_CHOMP_NEWLINE |
1245                                    PACKET_READ_DIE_ON_ERR_PACKET);
1246
1247                 receive_needs(&data, &reader);
1248                 if (data.want_obj.nr) {
1249                         get_common_commits(&data, &reader);
1250                         create_pack_file(&data, NULL);
1251                 }
1252         }
1253
1254         upload_pack_data_clear(&data);
1255 }
1256
1257 static int parse_want(struct packet_writer *writer, const char *line,
1258                       struct object_array *want_obj)
1259 {
1260         const char *arg;
1261         if (skip_prefix(line, "want ", &arg)) {
1262                 struct object_id oid;
1263                 struct object *o;
1264
1265                 if (get_oid_hex(arg, &oid))
1266                         die("git upload-pack: protocol error, "
1267                             "expected to get oid, not '%s'", line);
1268
1269                 o = parse_object(the_repository, &oid);
1270                 if (!o) {
1271                         packet_writer_error(writer,
1272                                             "upload-pack: not our ref %s",
1273                                             oid_to_hex(&oid));
1274                         die("git upload-pack: not our ref %s",
1275                             oid_to_hex(&oid));
1276                 }
1277
1278                 if (!(o->flags & WANTED)) {
1279                         o->flags |= WANTED;
1280                         add_object_array(o, NULL, want_obj);
1281                 }
1282
1283                 return 1;
1284         }
1285
1286         return 0;
1287 }
1288
1289 static int parse_want_ref(struct packet_writer *writer, const char *line,
1290                           struct string_list *wanted_refs,
1291                           struct object_array *want_obj)
1292 {
1293         const char *arg;
1294         if (skip_prefix(line, "want-ref ", &arg)) {
1295                 struct object_id oid;
1296                 struct string_list_item *item;
1297                 struct object *o;
1298
1299                 if (read_ref(arg, &oid)) {
1300                         packet_writer_error(writer, "unknown ref %s", arg);
1301                         die("unknown ref %s", arg);
1302                 }
1303
1304                 item = string_list_append(wanted_refs, arg);
1305                 item->util = oiddup(&oid);
1306
1307                 o = parse_object_or_die(&oid, arg);
1308                 if (!(o->flags & WANTED)) {
1309                         o->flags |= WANTED;
1310                         add_object_array(o, NULL, want_obj);
1311                 }
1312
1313                 return 1;
1314         }
1315
1316         return 0;
1317 }
1318
1319 static int parse_have(const char *line, struct oid_array *haves)
1320 {
1321         const char *arg;
1322         if (skip_prefix(line, "have ", &arg)) {
1323                 struct object_id oid;
1324
1325                 if (get_oid_hex(arg, &oid))
1326                         die("git upload-pack: expected SHA1 object, got '%s'", arg);
1327                 oid_array_append(haves, &oid);
1328                 return 1;
1329         }
1330
1331         return 0;
1332 }
1333
1334 static void process_args(struct packet_reader *request,
1335                          struct upload_pack_data *data)
1336 {
1337         while (packet_reader_read(request) == PACKET_READ_NORMAL) {
1338                 const char *arg = request->line;
1339                 const char *p;
1340
1341                 /* process want */
1342                 if (parse_want(&data->writer, arg, &data->want_obj))
1343                         continue;
1344                 if (data->allow_ref_in_want &&
1345                     parse_want_ref(&data->writer, arg, &data->wanted_refs,
1346                                    &data->want_obj))
1347                         continue;
1348                 /* process have line */
1349                 if (parse_have(arg, &data->haves))
1350                         continue;
1351
1352                 /* process args like thin-pack */
1353                 if (!strcmp(arg, "thin-pack")) {
1354                         data->use_thin_pack = 1;
1355                         continue;
1356                 }
1357                 if (!strcmp(arg, "ofs-delta")) {
1358                         data->use_ofs_delta = 1;
1359                         continue;
1360                 }
1361                 if (!strcmp(arg, "no-progress")) {
1362                         data->no_progress = 1;
1363                         continue;
1364                 }
1365                 if (!strcmp(arg, "include-tag")) {
1366                         data->use_include_tag = 1;
1367                         continue;
1368                 }
1369                 if (!strcmp(arg, "done")) {
1370                         data->done = 1;
1371                         continue;
1372                 }
1373
1374                 /* Shallow related arguments */
1375                 if (process_shallow(arg, &data->shallows))
1376                         continue;
1377                 if (process_deepen(arg, &data->depth))
1378                         continue;
1379                 if (process_deepen_since(arg, &data->deepen_since,
1380                                          &data->deepen_rev_list))
1381                         continue;
1382                 if (process_deepen_not(arg, &data->deepen_not,
1383                                        &data->deepen_rev_list))
1384                         continue;
1385                 if (!strcmp(arg, "deepen-relative")) {
1386                         data->deepen_relative = 1;
1387                         continue;
1388                 }
1389
1390                 if (data->allow_filter && skip_prefix(arg, "filter ", &p)) {
1391                         list_objects_filter_die_if_populated(&data->filter_options);
1392                         parse_list_objects_filter(&data->filter_options, p);
1393                         continue;
1394                 }
1395
1396                 if ((git_env_bool("GIT_TEST_SIDEBAND_ALL", 0) ||
1397                      data->allow_sideband_all) &&
1398                     !strcmp(arg, "sideband-all")) {
1399                         data->writer.use_sideband = 1;
1400                         continue;
1401                 }
1402
1403                 if (skip_prefix(arg, "packfile-uris ", &p)) {
1404                         string_list_split(&data->uri_protocols, p, ',', -1);
1405                         continue;
1406                 }
1407
1408                 /* ignore unknown lines maybe? */
1409                 die("unexpected line: '%s'", arg);
1410         }
1411
1412         if (data->uri_protocols.nr && !data->writer.use_sideband)
1413                 string_list_clear(&data->uri_protocols, 0);
1414
1415         if (request->status != PACKET_READ_FLUSH)
1416                 die(_("expected flush after fetch arguments"));
1417 }
1418
1419 static int process_haves(struct upload_pack_data *data, struct oid_array *common)
1420 {
1421         int i;
1422
1423         /* Process haves */
1424         for (i = 0; i < data->haves.nr; i++) {
1425                 const struct object_id *oid = &data->haves.oid[i];
1426
1427                 if (!has_object_file_with_flags(oid,
1428                                                 OBJECT_INFO_QUICK | OBJECT_INFO_SKIP_FETCH_OBJECT))
1429                         continue;
1430
1431                 oid_array_append(common, oid);
1432
1433                 do_got_oid(data, oid);
1434         }
1435
1436         return 0;
1437 }
1438
1439 static int send_acks(struct upload_pack_data *data, struct oid_array *acks)
1440 {
1441         int i;
1442
1443         packet_writer_write(&data->writer, "acknowledgments\n");
1444
1445         /* Send Acks */
1446         if (!acks->nr)
1447                 packet_writer_write(&data->writer, "NAK\n");
1448
1449         for (i = 0; i < acks->nr; i++) {
1450                 packet_writer_write(&data->writer, "ACK %s\n",
1451                                     oid_to_hex(&acks->oid[i]));
1452         }
1453
1454         if (ok_to_give_up(data)) {
1455                 /* Send Ready */
1456                 packet_writer_write(&data->writer, "ready\n");
1457                 return 1;
1458         }
1459
1460         return 0;
1461 }
1462
1463 static int process_haves_and_send_acks(struct upload_pack_data *data)
1464 {
1465         struct oid_array common = OID_ARRAY_INIT;
1466         int ret = 0;
1467
1468         process_haves(data, &common);
1469         if (data->done) {
1470                 ret = 1;
1471         } else if (send_acks(data, &common)) {
1472                 packet_writer_delim(&data->writer);
1473                 ret = 1;
1474         } else {
1475                 /* Add Flush */
1476                 packet_writer_flush(&data->writer);
1477                 ret = 0;
1478         }
1479
1480         oid_array_clear(&data->haves);
1481         oid_array_clear(&common);
1482         return ret;
1483 }
1484
1485 static void send_wanted_ref_info(struct upload_pack_data *data)
1486 {
1487         const struct string_list_item *item;
1488
1489         if (!data->wanted_refs.nr)
1490                 return;
1491
1492         packet_writer_write(&data->writer, "wanted-refs\n");
1493
1494         for_each_string_list_item(item, &data->wanted_refs) {
1495                 packet_writer_write(&data->writer, "%s %s\n",
1496                                     oid_to_hex(item->util),
1497                                     item->string);
1498         }
1499
1500         packet_writer_delim(&data->writer);
1501 }
1502
1503 static void send_shallow_info(struct upload_pack_data *data)
1504 {
1505         /* No shallow info needs to be sent */
1506         if (!data->depth && !data->deepen_rev_list && !data->shallows.nr &&
1507             !is_repository_shallow(the_repository))
1508                 return;
1509
1510         packet_writer_write(&data->writer, "shallow-info\n");
1511
1512         if (!send_shallow_list(data) &&
1513             is_repository_shallow(the_repository))
1514                 deepen(data, INFINITE_DEPTH);
1515
1516         packet_delim(1);
1517 }
1518
1519 enum fetch_state {
1520         FETCH_PROCESS_ARGS = 0,
1521         FETCH_SEND_ACKS,
1522         FETCH_SEND_PACK,
1523         FETCH_DONE,
1524 };
1525
1526 int upload_pack_v2(struct repository *r, struct argv_array *keys,
1527                    struct packet_reader *request)
1528 {
1529         enum fetch_state state = FETCH_PROCESS_ARGS;
1530         struct upload_pack_data data;
1531
1532         clear_object_flags(ALL_FLAGS);
1533
1534         upload_pack_data_init(&data);
1535         data.use_sideband = LARGE_PACKET_MAX;
1536
1537         git_config(upload_pack_config, &data);
1538
1539         while (state != FETCH_DONE) {
1540                 switch (state) {
1541                 case FETCH_PROCESS_ARGS:
1542                         process_args(request, &data);
1543
1544                         if (!data.want_obj.nr) {
1545                                 /*
1546                                  * Request didn't contain any 'want' lines,
1547                                  * guess they didn't want anything.
1548                                  */
1549                                 state = FETCH_DONE;
1550                         } else if (data.haves.nr) {
1551                                 /*
1552                                  * Request had 'have' lines, so lets ACK them.
1553                                  */
1554                                 state = FETCH_SEND_ACKS;
1555                         } else {
1556                                 /*
1557                                  * Request had 'want's but no 'have's so we can
1558                                  * immedietly go to construct and send a pack.
1559                                  */
1560                                 state = FETCH_SEND_PACK;
1561                         }
1562                         break;
1563                 case FETCH_SEND_ACKS:
1564                         if (process_haves_and_send_acks(&data))
1565                                 state = FETCH_SEND_PACK;
1566                         else
1567                                 state = FETCH_DONE;
1568                         break;
1569                 case FETCH_SEND_PACK:
1570                         send_wanted_ref_info(&data);
1571                         send_shallow_info(&data);
1572
1573                         if (data.uri_protocols.nr) {
1574                                 create_pack_file(&data, &data.uri_protocols);
1575                         } else {
1576                                 packet_writer_write(&data.writer, "packfile\n");
1577                                 create_pack_file(&data, NULL);
1578                         }
1579                         state = FETCH_DONE;
1580                         break;
1581                 case FETCH_DONE:
1582                         continue;
1583                 }
1584         }
1585
1586         upload_pack_data_clear(&data);
1587         return 0;
1588 }
1589
1590 int upload_pack_advertise(struct repository *r,
1591                           struct strbuf *value)
1592 {
1593         if (value) {
1594                 int allow_filter_value;
1595                 int allow_ref_in_want;
1596                 int allow_sideband_all_value;
1597                 char *str = NULL;
1598
1599                 strbuf_addstr(value, "shallow");
1600
1601                 if (!repo_config_get_bool(the_repository,
1602                                          "uploadpack.allowfilter",
1603                                          &allow_filter_value) &&
1604                     allow_filter_value)
1605                         strbuf_addstr(value, " filter");
1606
1607                 if (!repo_config_get_bool(the_repository,
1608                                          "uploadpack.allowrefinwant",
1609                                          &allow_ref_in_want) &&
1610                     allow_ref_in_want)
1611                         strbuf_addstr(value, " ref-in-want");
1612
1613                 if (git_env_bool("GIT_TEST_SIDEBAND_ALL", 0) ||
1614                     (!repo_config_get_bool(the_repository,
1615                                            "uploadpack.allowsidebandall",
1616                                            &allow_sideband_all_value) &&
1617                      allow_sideband_all_value))
1618                         strbuf_addstr(value, " sideband-all");
1619
1620                 if (!repo_config_get_string(the_repository,
1621                                             "uploadpack.blobpackfileuri",
1622                                             &str) &&
1623                     str) {
1624                         strbuf_addstr(value, " packfile-uris");
1625                         free(str);
1626                 }
1627         }
1628
1629         return 1;
1630 }