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

   1 #include "cache.h"
   2 #include "repository.h"
   3 #include "config.h"
   4 #include "lockfile.h"
   5 #include "refs.h"
   6 #include "pkt-line.h"
   7 #include "commit.h"
   8 #include "tag.h"
   9 #include "exec-cmd.h"
  10 #include "pack.h"
  11 #include "sideband.h"
  12 #include "fetch-pack.h"
  13 #include "remote.h"
  14 #include "run-command.h"
  15 #include "connect.h"
  16 #include "transport.h"
  17 #include "version.h"
  18 #include "oid-array.h"
  19 #include "oidset.h"
  20 #include "packfile.h"
  21 #include "object-store.h"
  22 #include "connected.h"
  23 #include "fetch-negotiator.h"
  24 #include "fsck.h"
  25 #include "shallow.h"
  26
  27 static int transfer_unpack_limit = -1;
  28 static int fetch_unpack_limit = -1;
  29 static int unpack_limit = 100;
  30 static int prefer_ofs_delta = 1;
  31 static int no_done;
  32 static int deepen_since_ok;
  33 static int deepen_not_ok;
  34 static int fetch_fsck_objects = -1;
  35 static int transfer_fsck_objects = -1;
  36 static int agent_supported;
  37 static int server_supports_filtering;
  38 static struct shallow_lock shallow_lock;
  39 static const char *alternate_shallow_file;
  40 static struct strbuf fsck_msg_types = STRBUF_INIT;
  41 static struct string_list uri_protocols = STRING_LIST_INIT_DUP;
  42
  43 /* Remember to update object flag allocation in object.h */
  44 #define COMPLETE        (1U << 0)
  45 #define ALTERNATE       (1U << 1)
  46
  47 /*
  48  * After sending this many "have"s if we do not get any new ACK , we
  49  * give up traversing our history.
  50  */
  51 #define MAX_IN_VAIN 256
  52
  53 static int multi_ack, use_sideband;
  54 /* Allow specifying sha1 if it is a ref tip. */
  55 #define ALLOW_TIP_SHA1  01
  56 /* Allow request of a sha1 if it is reachable from a ref (possibly hidden ref). */
  57 #define ALLOW_REACHABLE_SHA1    02
  58 static unsigned int allow_unadvertised_object_request;
  59
  60 __attribute__((format (printf, 2, 3)))
  61 static inline void print_verbose(const struct fetch_pack_args *args,
  62                                  const char *fmt, ...)
  63 {
  64         va_list params;
  65
  66         if (!args->verbose)
  67                 return;
  68
  69         va_start(params, fmt);
  70         vfprintf(stderr, fmt, params);
  71         va_end(params);
  72         fputc('\n', stderr);
  73 }
  74
  75 struct alternate_object_cache {
  76         struct object **items;
  77         size_t nr, alloc;
  78 };
  79
  80 static void cache_one_alternate(const struct object_id *oid,
  81                                 void *vcache)
  82 {
  83         struct alternate_object_cache *cache = vcache;
  84         struct object *obj = parse_object(the_repository, oid);
  85
  86         if (!obj || (obj->flags & ALTERNATE))
  87                 return;
  88
  89         obj->flags |= ALTERNATE;
  90         ALLOC_GROW(cache->items, cache->nr + 1, cache->alloc);
  91         cache->items[cache->nr++] = obj;
  92 }
  93
  94 static void for_each_cached_alternate(struct fetch_negotiator *negotiator,
  95                                       void (*cb)(struct fetch_negotiator *,
  96                                                  struct object *))
  97 {
  98         static int initialized;
  99         static struct alternate_object_cache cache;
 100         size_t i;
 101
 102         if (!initialized) {
 103                 for_each_alternate_ref(cache_one_alternate, &cache);
 104                 initialized = 1;
 105         }
 106
 107         for (i = 0; i < cache.nr; i++)
 108                 cb(negotiator, cache.items[i]);
 109 }
 110
 111 static struct commit *deref_without_lazy_fetch(const struct object_id *oid,
 112                                                int mark_tags_complete)
 113 {
 114         enum object_type type;
 115         struct object_info info = { .typep = &type };
 116
 117         while (1) {
 118                 if (oid_object_info_extended(the_repository, oid, &info,
 119                                              OBJECT_INFO_SKIP_FETCH_OBJECT | OBJECT_INFO_QUICK))
 120                         return NULL;
 121                 if (type == OBJ_TAG) {
 122                         struct tag *tag = (struct tag *)
 123                                 parse_object(the_repository, oid);
 124
 125                         if (!tag->tagged)
 126                                 return NULL;
 127                         if (mark_tags_complete)
 128                                 tag->object.flags |= COMPLETE;
 129                         oid = &tag->tagged->oid;
 130                 } else {
 131                         break;
 132                 }
 133         }
 134         if (type == OBJ_COMMIT)
 135                 return (struct commit *) parse_object(the_repository, oid);
 136         return NULL;
 137 }
 138
 139 static int rev_list_insert_ref(struct fetch_negotiator *negotiator,
 140                                const struct object_id *oid)
 141 {
 142         struct commit *c = deref_without_lazy_fetch(oid, 0);
 143
 144         if (c)
 145                 negotiator->add_tip(negotiator, c);
 146         return 0;
 147 }
 148
 149 static int rev_list_insert_ref_oid(const char *refname, const struct object_id *oid,
 150                                    int flag, void *cb_data)
 151 {
 152         return rev_list_insert_ref(cb_data, oid);
 153 }
 154
 155 enum ack_type {
 156         NAK = 0,
 157         ACK,
 158         ACK_continue,
 159         ACK_common,
 160         ACK_ready
 161 };
 162
 163 static void consume_shallow_list(struct fetch_pack_args *args,
 164                                  struct packet_reader *reader)
 165 {
 166         if (args->stateless_rpc && args->deepen) {
 167                 /* If we sent a depth we will get back "duplicate"
 168                  * shallow and unshallow commands every time there
 169                  * is a block of have lines exchanged.
 170                  */
 171                 while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
 172                         if (starts_with(reader->line, "shallow "))
 173                                 continue;
 174                         if (starts_with(reader->line, "unshallow "))
 175                                 continue;
 176                         die(_("git fetch-pack: expected shallow list"));
 177                 }
 178                 if (reader->status != PACKET_READ_FLUSH)
 179                         die(_("git fetch-pack: expected a flush packet after shallow list"));
 180         }
 181 }
 182
 183 static enum ack_type get_ack(struct packet_reader *reader,
 184                              struct object_id *result_oid)
 185 {
 186         int len;
 187         const char *arg;
 188
 189         if (packet_reader_read(reader) != PACKET_READ_NORMAL)
 190                 die(_("git fetch-pack: expected ACK/NAK, got a flush packet"));
 191         len = reader->pktlen;
 192
 193         if (!strcmp(reader->line, "NAK"))
 194                 return NAK;
 195         if (skip_prefix(reader->line, "ACK ", &arg)) {
 196                 const char *p;
 197                 if (!parse_oid_hex(arg, result_oid, &p)) {
 198                         len -= p - reader->line;
 199                         if (len < 1)
 200                                 return ACK;
 201                         if (strstr(p, "continue"))
 202                                 return ACK_continue;
 203                         if (strstr(p, "common"))
 204                                 return ACK_common;
 205                         if (strstr(p, "ready"))
 206                                 return ACK_ready;
 207                         return ACK;
 208                 }
 209         }
 210         die(_("git fetch-pack: expected ACK/NAK, got '%s'"), reader->line);
 211 }
 212
 213 static void send_request(struct fetch_pack_args *args,
 214                          int fd, struct strbuf *buf)
 215 {
 216         if (args->stateless_rpc) {
 217                 send_sideband(fd, -1, buf->buf, buf->len, LARGE_PACKET_MAX);
 218                 packet_flush(fd);
 219         } else {
 220                 if (write_in_full(fd, buf->buf, buf->len) < 0)
 221                         die_errno(_("unable to write to remote"));
 222         }
 223 }
 224
 225 static void insert_one_alternate_object(struct fetch_negotiator *negotiator,
 226                                         struct object *obj)
 227 {
 228         rev_list_insert_ref(negotiator, &obj->oid);
 229 }
 230
 231 #define INITIAL_FLUSH 16
 232 #define PIPESAFE_FLUSH 32
 233 #define LARGE_FLUSH 16384
 234
 235 static int next_flush(int stateless_rpc, int count)
 236 {
 237         if (stateless_rpc) {
 238                 if (count < LARGE_FLUSH)
 239                         count <<= 1;
 240                 else
 241                         count = count * 11 / 10;
 242         } else {
 243                 if (count < PIPESAFE_FLUSH)
 244                         count <<= 1;
 245                 else
 246                         count += PIPESAFE_FLUSH;
 247         }
 248         return count;
 249 }
 250
 251 static void mark_tips(struct fetch_negotiator *negotiator,
 252                       const struct oid_array *negotiation_tips)
 253 {
 254         int i;
 255
 256         if (!negotiation_tips) {
 257                 for_each_rawref(rev_list_insert_ref_oid, negotiator);
 258                 return;
 259         }
 260
 261         for (i = 0; i < negotiation_tips->nr; i++)
 262                 rev_list_insert_ref(negotiator, &negotiation_tips->oid[i]);
 263         return;
 264 }
 265
 266 static int find_common(struct fetch_negotiator *negotiator,
 267                        struct fetch_pack_args *args,
 268                        int fd[2], struct object_id *result_oid,
 269                        struct ref *refs)
 270 {
 271         int fetching;
 272         int count = 0, flushes = 0, flush_at = INITIAL_FLUSH, retval;
 273         const struct object_id *oid;
 274         unsigned in_vain = 0;
 275         int got_continue = 0;
 276         int got_ready = 0;
 277         struct strbuf req_buf = STRBUF_INIT;
 278         size_t state_len = 0;
 279         struct packet_reader reader;
 280
 281         if (args->stateless_rpc && multi_ack == 1)
 282                 die(_("--stateless-rpc requires multi_ack_detailed"));
 283
 284         packet_reader_init(&reader, fd[0], NULL, 0,
 285                            PACKET_READ_CHOMP_NEWLINE |
 286                            PACKET_READ_DIE_ON_ERR_PACKET);
 287
 288         mark_tips(negotiator, args->negotiation_tips);
 289         for_each_cached_alternate(negotiator, insert_one_alternate_object);
 290
 291         fetching = 0;
 292         for ( ; refs ; refs = refs->next) {
 293                 struct object_id *remote = &refs->old_oid;
 294                 const char *remote_hex;
 295                 struct object *o;
 296
 297                 /*
 298                  * If that object is complete (i.e. it is an ancestor of a
 299                  * local ref), we tell them we have it but do not have to
 300                  * tell them about its ancestors, which they already know
 301                  * about.
 302                  *
 303                  * We use lookup_object here because we are only
 304                  * interested in the case we *know* the object is
 305                  * reachable and we have already scanned it.
 306                  */
 307                 if (((o = lookup_object(the_repository, remote)) != NULL) &&
 308                                 (o->flags & COMPLETE)) {
 309                         continue;
 310                 }
 311
 312                 remote_hex = oid_to_hex(remote);
 313                 if (!fetching) {
 314                         struct strbuf c = STRBUF_INIT;
 315                         if (multi_ack == 2)     strbuf_addstr(&c, " multi_ack_detailed");
 316                         if (multi_ack == 1)     strbuf_addstr(&c, " multi_ack");
 317                         if (no_done)            strbuf_addstr(&c, " no-done");
 318                         if (use_sideband == 2)  strbuf_addstr(&c, " side-band-64k");
 319                         if (use_sideband == 1)  strbuf_addstr(&c, " side-band");
 320                         if (args->deepen_relative) strbuf_addstr(&c, " deepen-relative");
 321                         if (args->use_thin_pack) strbuf_addstr(&c, " thin-pack");
 322                         if (args->no_progress)   strbuf_addstr(&c, " no-progress");
 323                         if (args->include_tag)   strbuf_addstr(&c, " include-tag");
 324                         if (prefer_ofs_delta)   strbuf_addstr(&c, " ofs-delta");
 325                         if (deepen_since_ok)    strbuf_addstr(&c, " deepen-since");
 326                         if (deepen_not_ok)      strbuf_addstr(&c, " deepen-not");
 327                         if (agent_supported)    strbuf_addf(&c, " agent=%s",
 328                                                             git_user_agent_sanitized());
 329                         if (args->filter_options.choice)
 330                                 strbuf_addstr(&c, " filter");
 331                         packet_buf_write(&req_buf, "want %s%s\n", remote_hex, c.buf);
 332                         strbuf_release(&c);
 333                 } else
 334                         packet_buf_write(&req_buf, "want %s\n", remote_hex);
 335                 fetching++;
 336         }
 337
 338         if (!fetching) {
 339                 strbuf_release(&req_buf);
 340                 packet_flush(fd[1]);
 341                 return 1;
 342         }
 343
 344         if (is_repository_shallow(the_repository))
 345                 write_shallow_commits(&req_buf, 1, NULL);
 346         if (args->depth > 0)
 347                 packet_buf_write(&req_buf, "deepen %d", args->depth);
 348         if (args->deepen_since) {
 349                 timestamp_t max_age = approxidate(args->deepen_since);
 350                 packet_buf_write(&req_buf, "deepen-since %"PRItime, max_age);
 351         }
 352         if (args->deepen_not) {
 353                 int i;
 354                 for (i = 0; i < args->deepen_not->nr; i++) {
 355                         struct string_list_item *s = args->deepen_not->items + i;
 356                         packet_buf_write(&req_buf, "deepen-not %s", s->string);
 357                 }
 358         }
 359         if (server_supports_filtering && args->filter_options.choice) {
 360                 const char *spec =
 361                         expand_list_objects_filter_spec(&args->filter_options);
 362                 packet_buf_write(&req_buf, "filter %s", spec);
 363         }
 364         packet_buf_flush(&req_buf);
 365         state_len = req_buf.len;
 366
 367         if (args->deepen) {
 368                 const char *arg;
 369                 struct object_id oid;
 370
 371                 send_request(args, fd[1], &req_buf);
 372                 while (packet_reader_read(&reader) == PACKET_READ_NORMAL) {
 373                         if (skip_prefix(reader.line, "shallow ", &arg)) {
 374                                 if (get_oid_hex(arg, &oid))
 375                                         die(_("invalid shallow line: %s"), reader.line);
 376                                 register_shallow(the_repository, &oid);
 377                                 continue;
 378                         }
 379                         if (skip_prefix(reader.line, "unshallow ", &arg)) {
 380                                 if (get_oid_hex(arg, &oid))
 381                                         die(_("invalid unshallow line: %s"), reader.line);
 382                                 if (!lookup_object(the_repository, &oid))
 383                                         die(_("object not found: %s"), reader.line);
 384                                 /* make sure that it is parsed as shallow */
 385                                 if (!parse_object(the_repository, &oid))
 386                                         die(_("error in object: %s"), reader.line);
 387                                 if (unregister_shallow(&oid))
 388                                         die(_("no shallow found: %s"), reader.line);
 389                                 continue;
 390                         }
 391                         die(_("expected shallow/unshallow, got %s"), reader.line);
 392                 }
 393         } else if (!args->stateless_rpc)
 394                 send_request(args, fd[1], &req_buf);
 395
 396         if (!args->stateless_rpc) {
 397                 /* If we aren't using the stateless-rpc interface
 398                  * we don't need to retain the headers.
 399                  */
 400                 strbuf_setlen(&req_buf, 0);
 401                 state_len = 0;
 402         }
 403
 404         trace2_region_enter("fetch-pack", "negotiation_v0_v1", the_repository);
 405         flushes = 0;
 406         retval = -1;
 407         while ((oid = negotiator->next(negotiator))) {
 408                 packet_buf_write(&req_buf, "have %s\n", oid_to_hex(oid));
 409                 print_verbose(args, "have %s", oid_to_hex(oid));
 410                 in_vain++;
 411                 if (flush_at <= ++count) {
 412                         int ack;
 413
 414                         packet_buf_flush(&req_buf);
 415                         send_request(args, fd[1], &req_buf);
 416                         strbuf_setlen(&req_buf, state_len);
 417                         flushes++;
 418                         flush_at = next_flush(args->stateless_rpc, count);
 419
 420                         /*
 421                          * We keep one window "ahead" of the other side, and
 422                          * will wait for an ACK only on the next one
 423                          */
 424                         if (!args->stateless_rpc && count == INITIAL_FLUSH)
 425                                 continue;
 426
 427                         consume_shallow_list(args, &reader);
 428                         do {
 429                                 ack = get_ack(&reader, result_oid);
 430                                 if (ack)
 431                                         print_verbose(args, _("got %s %d %s"), "ack",
 432                                                       ack, oid_to_hex(result_oid));
 433                                 switch (ack) {
 434                                 case ACK:
 435                                         flushes = 0;
 436                                         multi_ack = 0;
 437                                         retval = 0;
 438                                         goto done;
 439                                 case ACK_common:
 440                                 case ACK_ready:
 441                                 case ACK_continue: {
 442                                         struct commit *commit =
 443                                                 lookup_commit(the_repository,
 444                                                               result_oid);
 445                                         int was_common;
 446
 447                                         if (!commit)
 448                                                 die(_("invalid commit %s"), oid_to_hex(result_oid));
 449                                         was_common = negotiator->ack(negotiator, commit);
 450                                         if (args->stateless_rpc
 451                                          && ack == ACK_common
 452                                          && !was_common) {
 453                                                 /* We need to replay the have for this object
 454                                                  * on the next RPC request so the peer knows
 455                                                  * it is in common with us.
 456                                                  */
 457                                                 const char *hex = oid_to_hex(result_oid);
 458                                                 packet_buf_write(&req_buf, "have %s\n", hex);
 459                                                 state_len = req_buf.len;
 460                                                 /*
 461                                                  * Reset in_vain because an ack
 462                                                  * for this commit has not been
 463                                                  * seen.
 464                                                  */
 465                                                 in_vain = 0;
 466                                         } else if (!args->stateless_rpc
 467                                                    || ack != ACK_common)
 468                                                 in_vain = 0;
 469                                         retval = 0;
 470                                         got_continue = 1;
 471                                         if (ack == ACK_ready)
 472                                                 got_ready = 1;
 473                                         break;
 474                                         }
 475                                 }
 476                         } while (ack);
 477                         flushes--;
 478                         if (got_continue && MAX_IN_VAIN < in_vain) {
 479                                 print_verbose(args, _("giving up"));
 480                                 break; /* give up */
 481                         }
 482                         if (got_ready)
 483                                 break;
 484                 }
 485         }
 486 done:
 487         trace2_region_leave("fetch-pack", "negotiation_v0_v1", the_repository);
 488         if (!got_ready || !no_done) {
 489                 packet_buf_write(&req_buf, "done\n");
 490                 send_request(args, fd[1], &req_buf);
 491         }
 492         print_verbose(args, _("done"));
 493         if (retval != 0) {
 494                 multi_ack = 0;
 495                 flushes++;
 496         }
 497         strbuf_release(&req_buf);
 498
 499         if (!got_ready || !no_done)
 500                 consume_shallow_list(args, &reader);
 501         while (flushes || multi_ack) {
 502                 int ack = get_ack(&reader, result_oid);
 503                 if (ack) {
 504                         print_verbose(args, _("got %s (%d) %s"), "ack",
 505                                       ack, oid_to_hex(result_oid));
 506                         if (ack == ACK)
 507                                 return 0;
 508                         multi_ack = 1;
 509                         continue;
 510                 }
 511                 flushes--;
 512         }
 513         /* it is no error to fetch into a completely empty repo */
 514         return count ? retval : 0;
 515 }
 516
 517 static struct commit_list *complete;
 518
 519 static int mark_complete(const struct object_id *oid)
 520 {
 521         struct commit *commit = deref_without_lazy_fetch(oid, 1);
 522
 523         if (commit && !(commit->object.flags & COMPLETE)) {
 524                 commit->object.flags |= COMPLETE;
 525                 commit_list_insert(commit, &complete);
 526         }
 527         return 0;
 528 }
 529
 530 static int mark_complete_oid(const char *refname, const struct object_id *oid,
 531                              int flag, void *cb_data)
 532 {
 533         return mark_complete(oid);
 534 }
 535
 536 static void mark_recent_complete_commits(struct fetch_pack_args *args,
 537                                          timestamp_t cutoff)
 538 {
 539         while (complete && cutoff <= complete->item->date) {
 540                 print_verbose(args, _("Marking %s as complete"),
 541                               oid_to_hex(&complete->item->object.oid));
 542                 pop_most_recent_commit(&complete, COMPLETE);
 543         }
 544 }
 545
 546 static void add_refs_to_oidset(struct oidset *oids, struct ref *refs)
 547 {
 548         for (; refs; refs = refs->next)
 549                 oidset_insert(oids, &refs->old_oid);
 550 }
 551
 552 static int is_unmatched_ref(const struct ref *ref)
 553 {
 554         struct object_id oid;
 555         const char *p;
 556         return  ref->match_status == REF_NOT_MATCHED &&
 557                 !parse_oid_hex(ref->name, &oid, &p) &&
 558                 *p == '\0' &&
 559                 oideq(&oid, &ref->old_oid);
 560 }
 561
 562 static void filter_refs(struct fetch_pack_args *args,
 563                         struct ref **refs,
 564                         struct ref **sought, int nr_sought)
 565 {
 566         struct ref *newlist = NULL;
 567         struct ref **newtail = &newlist;
 568         struct ref *unmatched = NULL;
 569         struct ref *ref, *next;
 570         struct oidset tip_oids = OIDSET_INIT;
 571         int i;
 572         int strict = !(allow_unadvertised_object_request &
 573                        (ALLOW_TIP_SHA1 | ALLOW_REACHABLE_SHA1));
 574
 575         i = 0;
 576         for (ref = *refs; ref; ref = next) {
 577                 int keep = 0;
 578                 next = ref->next;
 579
 580                 if (starts_with(ref->name, "refs/") &&
 581                     check_refname_format(ref->name, 0)) {
 582                         /*
 583                          * trash or a peeled value; do not even add it to
 584                          * unmatched list
 585                          */
 586                         free_one_ref(ref);
 587                         continue;
 588                 } else {
 589                         while (i < nr_sought) {
 590                                 int cmp = strcmp(ref->name, sought[i]->name);
 591                                 if (cmp < 0)
 592                                         break; /* definitely do not have it */
 593                                 else if (cmp == 0) {
 594                                         keep = 1; /* definitely have it */
 595                                         sought[i]->match_status = REF_MATCHED;
 596                                 }
 597                                 i++;
 598                         }
 599
 600                         if (!keep && args->fetch_all &&
 601                             (!args->deepen || !starts_with(ref->name, "refs/tags/")))
 602                                 keep = 1;
 603                 }
 604
 605                 if (keep) {
 606                         *newtail = ref;
 607                         ref->next = NULL;
 608                         newtail = &ref->next;
 609                 } else {
 610                         ref->next = unmatched;
 611                         unmatched = ref;
 612                 }
 613         }
 614
 615         if (strict) {
 616                 for (i = 0; i < nr_sought; i++) {
 617                         ref = sought[i];
 618                         if (!is_unmatched_ref(ref))
 619                                 continue;
 620
 621                         add_refs_to_oidset(&tip_oids, unmatched);
 622                         add_refs_to_oidset(&tip_oids, newlist);
 623                         break;
 624                 }
 625         }
 626
 627         /* Append unmatched requests to the list */
 628         for (i = 0; i < nr_sought; i++) {
 629                 ref = sought[i];
 630                 if (!is_unmatched_ref(ref))
 631                         continue;
 632
 633                 if (!strict || oidset_contains(&tip_oids, &ref->old_oid)) {
 634                         ref->match_status = REF_MATCHED;
 635                         *newtail = copy_ref(ref);
 636                         newtail = &(*newtail)->next;
 637                 } else {
 638                         ref->match_status = REF_UNADVERTISED_NOT_ALLOWED;
 639                 }
 640         }
 641
 642         oidset_clear(&tip_oids);
 643         free_refs(unmatched);
 644
 645         *refs = newlist;
 646 }
 647
 648 static void mark_alternate_complete(struct fetch_negotiator *unused,
 649                                     struct object *obj)
 650 {
 651         mark_complete(&obj->oid);
 652 }
 653
 654 struct loose_object_iter {
 655         struct oidset *loose_object_set;
 656         struct ref *refs;
 657 };
 658
 659 /*
 660  * Mark recent commits available locally and reachable from a local ref as
 661  * COMPLETE.
 662  *
 663  * The cutoff time for recency is determined by this heuristic: it is the
 664  * earliest commit time of the objects in refs that are commits and that we know
 665  * the commit time of.
 666  */
 667 static void mark_complete_and_common_ref(struct fetch_negotiator *negotiator,
 668                                          struct fetch_pack_args *args,
 669                                          struct ref **refs)
 670 {
 671         struct ref *ref;
 672         int old_save_commit_buffer = save_commit_buffer;
 673         timestamp_t cutoff = 0;
 674
 675         save_commit_buffer = 0;
 676
 677         trace2_region_enter("fetch-pack", "parse_remote_refs_and_find_cutoff", NULL);
 678         for (ref = *refs; ref; ref = ref->next) {
 679                 struct object *o;
 680
 681                 if (!has_object_file_with_flags(&ref->old_oid,
 682                                                 OBJECT_INFO_QUICK |
 683                                                         OBJECT_INFO_SKIP_FETCH_OBJECT))
 684                         continue;
 685                 o = parse_object(the_repository, &ref->old_oid);
 686                 if (!o)
 687                         continue;
 688
 689                 /*
 690                  * We already have it -- which may mean that we were
 691                  * in sync with the other side at some time after
 692                  * that (it is OK if we guess wrong here).
 693                  */
 694                 if (o->type == OBJ_COMMIT) {
 695                         struct commit *commit = (struct commit *)o;
 696                         if (!cutoff || cutoff < commit->date)
 697                                 cutoff = commit->date;
 698                 }
 699         }
 700         trace2_region_leave("fetch-pack", "parse_remote_refs_and_find_cutoff", NULL);
 701
 702         /*
 703          * This block marks all local refs as COMPLETE, and then recursively marks all
 704          * parents of those refs as COMPLETE.
 705          */
 706         trace2_region_enter("fetch-pack", "mark_complete_local_refs", NULL);
 707         if (!args->deepen) {
 708                 for_each_rawref(mark_complete_oid, NULL);
 709                 for_each_cached_alternate(NULL, mark_alternate_complete);
 710                 commit_list_sort_by_date(&complete);
 711                 if (cutoff)
 712                         mark_recent_complete_commits(args, cutoff);
 713         }
 714         trace2_region_leave("fetch-pack", "mark_complete_local_refs", NULL);
 715
 716         /*
 717          * Mark all complete remote refs as common refs.
 718          * Don't mark them common yet; the server has to be told so first.
 719          */
 720         trace2_region_enter("fetch-pack", "mark_common_remote_refs", NULL);
 721         for (ref = *refs; ref; ref = ref->next) {
 722                 struct commit *c = deref_without_lazy_fetch(&ref->old_oid, 0);
 723
 724                 if (!c || !(c->object.flags & COMPLETE))
 725                         continue;
 726
 727                 negotiator->known_common(negotiator, c);
 728         }
 729         trace2_region_leave("fetch-pack", "mark_common_remote_refs", NULL);
 730
 731         save_commit_buffer = old_save_commit_buffer;
 732 }
 733
 734 /*
 735  * Returns 1 if every object pointed to by the given remote refs is available
 736  * locally and reachable from a local ref, and 0 otherwise.
 737  */
 738 static int everything_local(struct fetch_pack_args *args,
 739                             struct ref **refs)
 740 {
 741         struct ref *ref;
 742         int retval;
 743
 744         for (retval = 1, ref = *refs; ref ; ref = ref->next) {
 745                 const struct object_id *remote = &ref->old_oid;
 746                 struct object *o;
 747
 748                 o = lookup_object(the_repository, remote);
 749                 if (!o || !(o->flags & COMPLETE)) {
 750                         retval = 0;
 751                         print_verbose(args, "want %s (%s)", oid_to_hex(remote),
 752                                       ref->name);
 753                         continue;
 754                 }
 755                 print_verbose(args, _("already have %s (%s)"), oid_to_hex(remote),
 756                               ref->name);
 757         }
 758
 759         return retval;
 760 }
 761
 762 static int sideband_demux(int in, int out, void *data)
 763 {
 764         int *xd = data;
 765         int ret;
 766
 767         ret = recv_sideband("fetch-pack", xd[0], out);
 768         close(out);
 769         return ret;
 770 }
 771
 772 static void write_promisor_file(const char *keep_name,
 773                                 struct ref **sought, int nr_sought)
 774 {
 775         struct strbuf promisor_name = STRBUF_INIT;
 776         int suffix_stripped;
 777         FILE *output;
 778         int i;
 779
 780         strbuf_addstr(&promisor_name, keep_name);
 781         suffix_stripped = strbuf_strip_suffix(&promisor_name, ".keep");
 782         if (!suffix_stripped)
 783                 BUG("name of pack lockfile should end with .keep (was '%s')",
 784                     keep_name);
 785         strbuf_addstr(&promisor_name, ".promisor");
 786
 787         output = xfopen(promisor_name.buf, "w");
 788         for (i = 0; i < nr_sought; i++)
 789                 fprintf(output, "%s %s\n", oid_to_hex(&sought[i]->old_oid),
 790                         sought[i]->name);
 791         fclose(output);
 792
 793         strbuf_release(&promisor_name);
 794 }
 795
 796 static int get_pack(struct fetch_pack_args *args,
 797                     int xd[2], struct string_list *pack_lockfiles,
 798                     int only_packfile,
 799                     struct ref **sought, int nr_sought)
 800 {
 801         struct async demux;
 802         int do_keep = args->keep_pack;
 803         const char *cmd_name;
 804         struct pack_header header;
 805         int pass_header = 0;
 806         struct child_process cmd = CHILD_PROCESS_INIT;
 807         int ret;
 808
 809         memset(&demux, 0, sizeof(demux));
 810         if (use_sideband) {
 811                 /* xd[] is talking with upload-pack; subprocess reads from
 812                  * xd[0], spits out band#2 to stderr, and feeds us band#1
 813                  * through demux->out.
 814                  */
 815                 demux.proc = sideband_demux;
 816                 demux.data = xd;
 817                 demux.out = -1;
 818                 demux.isolate_sigpipe = 1;
 819                 if (start_async(&demux))
 820                         die(_("fetch-pack: unable to fork off sideband demultiplexer"));
 821         }
 822         else
 823                 demux.out = xd[0];
 824
 825         if (!args->keep_pack && unpack_limit) {
 826
 827                 if (read_pack_header(demux.out, &header))
 828                         die(_("protocol error: bad pack header"));
 829                 pass_header = 1;
 830                 if (ntohl(header.hdr_entries) < unpack_limit)
 831                         do_keep = 0;
 832                 else
 833                         do_keep = 1;
 834         }
 835
 836         if (alternate_shallow_file) {
 837                 strvec_push(&cmd.args, "--shallow-file");
 838                 strvec_push(&cmd.args, alternate_shallow_file);
 839         }
 840
 841         if (do_keep || args->from_promisor) {
 842                 if (pack_lockfiles)
 843                         cmd.out = -1;
 844                 cmd_name = "index-pack";
 845                 strvec_push(&cmd.args, cmd_name);
 846                 strvec_push(&cmd.args, "--stdin");
 847                 if (!args->quiet && !args->no_progress)
 848                         strvec_push(&cmd.args, "-v");
 849                 if (args->use_thin_pack)
 850                         strvec_push(&cmd.args, "--fix-thin");
 851                 if (do_keep && (args->lock_pack || unpack_limit)) {
 852                         char hostname[HOST_NAME_MAX + 1];
 853                         if (xgethostname(hostname, sizeof(hostname)))
 854                                 xsnprintf(hostname, sizeof(hostname), "localhost");
 855                         strvec_pushf(&cmd.args,
 856                                      "--keep=fetch-pack %"PRIuMAX " on %s",
 857                                      (uintmax_t)getpid(), hostname);
 858                 }
 859                 if (only_packfile && args->check_self_contained_and_connected)
 860                         strvec_push(&cmd.args, "--check-self-contained-and-connected");
 861                 else
 862                         /*
 863                          * We cannot perform any connectivity checks because
 864                          * not all packs have been downloaded; let the caller
 865                          * have this responsibility.
 866                          */
 867                         args->check_self_contained_and_connected = 0;
 868                 /*
 869                  * If we're obtaining the filename of a lockfile, we'll use
 870                  * that filename to write a .promisor file with more
 871                  * information below. If not, we need index-pack to do it for
 872                  * us.
 873                  */
 874                 if (!(do_keep && pack_lockfiles) && args->from_promisor)
 875                         strvec_push(&cmd.args, "--promisor");
 876         }
 877         else {
 878                 cmd_name = "unpack-objects";
 879                 strvec_push(&cmd.args, cmd_name);
 880                 if (args->quiet || args->no_progress)
 881                         strvec_push(&cmd.args, "-q");
 882                 args->check_self_contained_and_connected = 0;
 883         }
 884
 885         if (pass_header)
 886                 strvec_pushf(&cmd.args, "--pack_header=%"PRIu32",%"PRIu32,
 887                              ntohl(header.hdr_version),
 888                                  ntohl(header.hdr_entries));
 889         if (fetch_fsck_objects >= 0
 890             ? fetch_fsck_objects
 891             : transfer_fsck_objects >= 0
 892             ? transfer_fsck_objects
 893             : 0) {
 894                 if (args->from_promisor)
 895                         /*
 896                          * We cannot use --strict in index-pack because it
 897                          * checks both broken objects and links, but we only
 898                          * want to check for broken objects.
 899                          */
 900                         strvec_push(&cmd.args, "--fsck-objects");
 901                 else
 902                         strvec_pushf(&cmd.args, "--strict%s",
 903                                      fsck_msg_types.buf);
 904         }
 905
 906         cmd.in = demux.out;
 907         cmd.git_cmd = 1;
 908         if (start_command(&cmd))
 909                 die(_("fetch-pack: unable to fork off %s"), cmd_name);
 910         if (do_keep && pack_lockfiles) {
 911                 string_list_append_nodup(pack_lockfiles,
 912                                          index_pack_lockfile(cmd.out));
 913                 close(cmd.out);
 914         }
 915
 916         if (!use_sideband)
 917                 /* Closed by start_command() */
 918                 xd[0] = -1;
 919
 920         ret = finish_command(&cmd);
 921         if (!ret || (args->check_self_contained_and_connected && ret == 1))
 922                 args->self_contained_and_connected =
 923                         args->check_self_contained_and_connected &&
 924                         ret == 0;
 925         else
 926                 die(_("%s failed"), cmd_name);
 927         if (use_sideband && finish_async(&demux))
 928                 die(_("error in sideband demultiplexer"));
 929
 930         /*
 931          * Now that index-pack has succeeded, write the promisor file using the
 932          * obtained .keep filename if necessary
 933          */
 934         if (do_keep && pack_lockfiles && pack_lockfiles->nr && args->from_promisor)
 935                 write_promisor_file(pack_lockfiles->items[0].string, sought, nr_sought);
 936
 937         return 0;
 938 }
 939
 940 static int cmp_ref_by_name(const void *a_, const void *b_)
 941 {
 942         const struct ref *a = *((const struct ref **)a_);
 943         const struct ref *b = *((const struct ref **)b_);
 944         return strcmp(a->name, b->name);
 945 }
 946
 947 static struct ref *do_fetch_pack(struct fetch_pack_args *args,
 948                                  int fd[2],
 949                                  const struct ref *orig_ref,
 950                                  struct ref **sought, int nr_sought,
 951                                  struct shallow_info *si,
 952                                  struct string_list *pack_lockfiles)
 953 {
 954         struct repository *r = the_repository;
 955         struct ref *ref = copy_ref_list(orig_ref);
 956         struct object_id oid;
 957         const char *agent_feature;
 958         int agent_len;
 959         struct fetch_negotiator negotiator_alloc;
 960         struct fetch_negotiator *negotiator;
 961
 962         negotiator = &negotiator_alloc;
 963         fetch_negotiator_init(r, negotiator);
 964
 965         sort_ref_list(&ref, ref_compare_name);
 966         QSORT(sought, nr_sought, cmp_ref_by_name);
 967
 968         if ((agent_feature = server_feature_value("agent", &agent_len))) {
 969                 agent_supported = 1;
 970                 if (agent_len)
 971                         print_verbose(args, _("Server version is %.*s"),
 972                                       agent_len, agent_feature);
 973         }
 974
 975         if (server_supports("shallow"))
 976                 print_verbose(args, _("Server supports %s"), "shallow");
 977         else if (args->depth > 0 || is_repository_shallow(r))
 978                 die(_("Server does not support shallow clients"));
 979         if (args->depth > 0 || args->deepen_since || args->deepen_not)
 980                 args->deepen = 1;
 981         if (server_supports("multi_ack_detailed")) {
 982                 print_verbose(args, _("Server supports %s"), "multi_ack_detailed");
 983                 multi_ack = 2;
 984                 if (server_supports("no-done")) {
 985                         print_verbose(args, _("Server supports %s"), "no-done");
 986                         if (args->stateless_rpc)
 987                                 no_done = 1;
 988                 }
 989         }
 990         else if (server_supports("multi_ack")) {
 991                 print_verbose(args, _("Server supports %s"), "multi_ack");
 992                 multi_ack = 1;
 993         }
 994         if (server_supports("side-band-64k")) {
 995                 print_verbose(args, _("Server supports %s"), "side-band-64k");
 996                 use_sideband = 2;
 997         }
 998         else if (server_supports("side-band")) {
 999                 print_verbose(args, _("Server supports %s"), "side-band");
1000                 use_sideband = 1;
1001         }
1002         if (server_supports("allow-tip-sha1-in-want")) {
1003                 print_verbose(args, _("Server supports %s"), "allow-tip-sha1-in-want");
1004                 allow_unadvertised_object_request |= ALLOW_TIP_SHA1;
1005         }
1006         if (server_supports("allow-reachable-sha1-in-want")) {
1007                 print_verbose(args, _("Server supports %s"), "allow-reachable-sha1-in-want");
1008                 allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
1009         }
1010         if (server_supports("thin-pack"))
1011                 print_verbose(args, _("Server supports %s"), "thin-pack");
1012         else
1013                 args->use_thin_pack = 0;
1014         if (server_supports("no-progress"))
1015                 print_verbose(args, _("Server supports %s"), "no-progress");
1016         else
1017                 args->no_progress = 0;
1018         if (server_supports("include-tag"))
1019                 print_verbose(args, _("Server supports %s"), "include-tag");
1020         else
1021                 args->include_tag = 0;
1022         if (server_supports("ofs-delta"))
1023                 print_verbose(args, _("Server supports %s"), "ofs-delta");
1024         else
1025                 prefer_ofs_delta = 0;
1026
1027         if (server_supports("filter")) {
1028                 server_supports_filtering = 1;
1029                 print_verbose(args, _("Server supports %s"), "filter");
1030         } else if (args->filter_options.choice) {
1031                 warning("filtering not recognized by server, ignoring");
1032         }
1033
1034         if (server_supports("deepen-since")) {
1035                 print_verbose(args, _("Server supports %s"), "deepen-since");
1036                 deepen_since_ok = 1;
1037         } else if (args->deepen_since)
1038                 die(_("Server does not support --shallow-since"));
1039         if (server_supports("deepen-not")) {
1040                 print_verbose(args, _("Server supports %s"), "deepen-not");
1041                 deepen_not_ok = 1;
1042         } else if (args->deepen_not)
1043                 die(_("Server does not support --shallow-exclude"));
1044         if (server_supports("deepen-relative"))
1045                 print_verbose(args, _("Server supports %s"), "deepen-relative");
1046         else if (args->deepen_relative)
1047                 die(_("Server does not support --deepen"));
1048         if (!server_supports_hash(the_hash_algo->name, NULL))
1049                 die(_("Server does not support this repository's object format"));
1050
1051         mark_complete_and_common_ref(negotiator, args, &ref);
1052         filter_refs(args, &ref, sought, nr_sought);
1053         if (everything_local(args, &ref)) {
1054                 packet_flush(fd[1]);
1055                 goto all_done;
1056         }
1057         if (find_common(negotiator, args, fd, &oid, ref) < 0)
1058                 if (!args->keep_pack)
1059                         /* When cloning, it is not unusual to have
1060                          * no common commit.
1061                          */
1062                         warning(_("no common commits"));
1063
1064         if (args->stateless_rpc)
1065                 packet_flush(fd[1]);
1066         if (args->deepen)
1067                 setup_alternate_shallow(&shallow_lock, &alternate_shallow_file,
1068                                         NULL);
1069         else if (si->nr_ours || si->nr_theirs)
1070                 alternate_shallow_file = setup_temporary_shallow(si->shallow);
1071         else
1072                 alternate_shallow_file = NULL;
1073         if (get_pack(args, fd, pack_lockfiles, 1, sought, nr_sought))
1074                 die(_("git fetch-pack: fetch failed."));
1075
1076  all_done:
1077         if (negotiator)
1078                 negotiator->release(negotiator);
1079         return ref;
1080 }
1081
1082 static void add_shallow_requests(struct strbuf *req_buf,
1083                                  const struct fetch_pack_args *args)
1084 {
1085         if (is_repository_shallow(the_repository))
1086                 write_shallow_commits(req_buf, 1, NULL);
1087         if (args->depth > 0)
1088                 packet_buf_write(req_buf, "deepen %d", args->depth);
1089         if (args->deepen_since) {
1090                 timestamp_t max_age = approxidate(args->deepen_since);
1091                 packet_buf_write(req_buf, "deepen-since %"PRItime, max_age);
1092         }
1093         if (args->deepen_not) {
1094                 int i;
1095                 for (i = 0; i < args->deepen_not->nr; i++) {
1096                         struct string_list_item *s = args->deepen_not->items + i;
1097                         packet_buf_write(req_buf, "deepen-not %s", s->string);
1098                 }
1099         }
1100         if (args->deepen_relative)
1101                 packet_buf_write(req_buf, "deepen-relative\n");
1102 }
1103
1104 static void add_wants(const struct ref *wants, struct strbuf *req_buf)
1105 {
1106         int use_ref_in_want = server_supports_feature("fetch", "ref-in-want", 0);
1107
1108         for ( ; wants ; wants = wants->next) {
1109                 const struct object_id *remote = &wants->old_oid;
1110                 struct object *o;
1111
1112                 /*
1113                  * If that object is complete (i.e. it is an ancestor of a
1114                  * local ref), we tell them we have it but do not have to
1115                  * tell them about its ancestors, which they already know
1116                  * about.
1117                  *
1118                  * We use lookup_object here because we are only
1119                  * interested in the case we *know* the object is
1120                  * reachable and we have already scanned it.
1121                  */
1122                 if (((o = lookup_object(the_repository, remote)) != NULL) &&
1123                     (o->flags & COMPLETE)) {
1124                         continue;
1125                 }
1126
1127                 if (!use_ref_in_want || wants->exact_oid)
1128                         packet_buf_write(req_buf, "want %s\n", oid_to_hex(remote));
1129                 else
1130                         packet_buf_write(req_buf, "want-ref %s\n", wants->name);
1131         }
1132 }
1133
1134 static void add_common(struct strbuf *req_buf, struct oidset *common)
1135 {
1136         struct oidset_iter iter;
1137         const struct object_id *oid;
1138         oidset_iter_init(common, &iter);
1139
1140         while ((oid = oidset_iter_next(&iter))) {
1141                 packet_buf_write(req_buf, "have %s\n", oid_to_hex(oid));
1142         }
1143 }
1144
1145 static int add_haves(struct fetch_negotiator *negotiator,
1146                      int seen_ack,
1147                      struct strbuf *req_buf,
1148                      int *haves_to_send, int *in_vain)
1149 {
1150         int ret = 0;
1151         int haves_added = 0;
1152         const struct object_id *oid;
1153
1154         while ((oid = negotiator->next(negotiator))) {
1155                 packet_buf_write(req_buf, "have %s\n", oid_to_hex(oid));
1156                 if (++haves_added >= *haves_to_send)
1157                         break;
1158         }
1159
1160         *in_vain += haves_added;
1161         if (!haves_added || (seen_ack && *in_vain >= MAX_IN_VAIN)) {
1162                 /* Send Done */
1163                 packet_buf_write(req_buf, "done\n");
1164                 ret = 1;
1165         }
1166
1167         /* Increase haves to send on next round */
1168         *haves_to_send = next_flush(1, *haves_to_send);
1169
1170         return ret;
1171 }
1172
1173 static int send_fetch_request(struct fetch_negotiator *negotiator, int fd_out,
1174                               struct fetch_pack_args *args,
1175                               const struct ref *wants, struct oidset *common,
1176                               int *haves_to_send, int *in_vain,
1177                               int sideband_all, int seen_ack)
1178 {
1179         int ret = 0;
1180         const char *hash_name;
1181         struct strbuf req_buf = STRBUF_INIT;
1182
1183         if (server_supports_v2("fetch", 1))
1184                 packet_buf_write(&req_buf, "command=fetch");
1185         if (server_supports_v2("agent", 0))
1186                 packet_buf_write(&req_buf, "agent=%s", git_user_agent_sanitized());
1187         if (args->server_options && args->server_options->nr &&
1188             server_supports_v2("server-option", 1)) {
1189                 int i;
1190                 for (i = 0; i < args->server_options->nr; i++)
1191                         packet_buf_write(&req_buf, "server-option=%s",
1192                                          args->server_options->items[i].string);
1193         }
1194
1195         if (server_feature_v2("object-format", &hash_name)) {
1196                 int hash_algo = hash_algo_by_name(hash_name);
1197                 if (hash_algo_by_ptr(the_hash_algo) != hash_algo)
1198                         die(_("mismatched algorithms: client %s; server %s"),
1199                             the_hash_algo->name, hash_name);
1200                 packet_write_fmt(fd_out, "object-format=%s", the_hash_algo->name);
1201         } else if (hash_algo_by_ptr(the_hash_algo) != GIT_HASH_SHA1) {
1202                 die(_("the server does not support algorithm '%s'"),
1203                     the_hash_algo->name);
1204         }
1205
1206         packet_buf_delim(&req_buf);
1207         if (args->use_thin_pack)
1208                 packet_buf_write(&req_buf, "thin-pack");
1209         if (args->no_progress)
1210                 packet_buf_write(&req_buf, "no-progress");
1211         if (args->include_tag)
1212                 packet_buf_write(&req_buf, "include-tag");
1213         if (prefer_ofs_delta)
1214                 packet_buf_write(&req_buf, "ofs-delta");
1215         if (sideband_all)
1216                 packet_buf_write(&req_buf, "sideband-all");
1217
1218         /* Add shallow-info and deepen request */
1219         if (server_supports_feature("fetch", "shallow", 0))
1220                 add_shallow_requests(&req_buf, args);
1221         else if (is_repository_shallow(the_repository) || args->deepen)
1222                 die(_("Server does not support shallow requests"));
1223
1224         /* Add filter */
1225         if (server_supports_feature("fetch", "filter", 0) &&
1226             args->filter_options.choice) {
1227                 const char *spec =
1228                         expand_list_objects_filter_spec(&args->filter_options);
1229                 print_verbose(args, _("Server supports filter"));
1230                 packet_buf_write(&req_buf, "filter %s", spec);
1231         } else if (args->filter_options.choice) {
1232                 warning("filtering not recognized by server, ignoring");
1233         }
1234
1235         if (server_supports_feature("fetch", "packfile-uris", 0)) {
1236                 int i;
1237                 struct strbuf to_send = STRBUF_INIT;
1238
1239                 for (i = 0; i < uri_protocols.nr; i++) {
1240                         const char *s = uri_protocols.items[i].string;
1241
1242                         if (!strcmp(s, "https") || !strcmp(s, "http")) {
1243                                 if (to_send.len)
1244                                         strbuf_addch(&to_send, ',');
1245                                 strbuf_addstr(&to_send, s);
1246                         }
1247                 }
1248                 if (to_send.len) {
1249                         packet_buf_write(&req_buf, "packfile-uris %s",
1250                                          to_send.buf);
1251                         strbuf_release(&to_send);
1252                 }
1253         }
1254
1255         /* add wants */
1256         add_wants(wants, &req_buf);
1257
1258         /* Add all of the common commits we've found in previous rounds */
1259         add_common(&req_buf, common);
1260
1261         /* Add initial haves */
1262         ret = add_haves(negotiator, seen_ack, &req_buf,
1263                         haves_to_send, in_vain);
1264
1265         /* Send request */
1266         packet_buf_flush(&req_buf);
1267         if (write_in_full(fd_out, req_buf.buf, req_buf.len) < 0)
1268                 die_errno(_("unable to write request to remote"));
1269
1270         strbuf_release(&req_buf);
1271         return ret;
1272 }
1273
1274 /*
1275  * Processes a section header in a server's response and checks if it matches
1276  * `section`.  If the value of `peek` is 1, the header line will be peeked (and
1277  * not consumed); if 0, the line will be consumed and the function will die if
1278  * the section header doesn't match what was expected.
1279  */
1280 static int process_section_header(struct packet_reader *reader,
1281                                   const char *section, int peek)
1282 {
1283         int ret;
1284
1285         if (packet_reader_peek(reader) != PACKET_READ_NORMAL)
1286                 die(_("error reading section header '%s'"), section);
1287
1288         ret = !strcmp(reader->line, section);
1289
1290         if (!peek) {
1291                 if (!ret)
1292                         die(_("expected '%s', received '%s'"),
1293                             section, reader->line);
1294                 packet_reader_read(reader);
1295         }
1296
1297         return ret;
1298 }
1299
1300 enum common_found {
1301         /*
1302          * No commit was found to be possessed by both the client and the
1303          * server, and "ready" was not received.
1304          */
1305         NO_COMMON_FOUND,
1306
1307         /*
1308          * At least one commit was found to be possessed by both the client and
1309          * the server, and "ready" was not received.
1310          */
1311         COMMON_FOUND,
1312
1313         /*
1314          * "ready" was received, indicating that the server is ready to send
1315          * the packfile without any further negotiation.
1316          */
1317         READY
1318 };
1319
1320 static enum common_found process_acks(struct fetch_negotiator *negotiator,
1321                                       struct packet_reader *reader,
1322                                       struct oidset *common)
1323 {
1324         /* received */
1325         int received_ready = 0;
1326         int received_ack = 0;
1327
1328         process_section_header(reader, "acknowledgments", 0);
1329         while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
1330                 const char *arg;
1331
1332                 if (!strcmp(reader->line, "NAK"))
1333                         continue;
1334
1335                 if (skip_prefix(reader->line, "ACK ", &arg)) {
1336                         struct object_id oid;
1337                         received_ack = 1;
1338                         if (!get_oid_hex(arg, &oid)) {
1339                                 struct commit *commit;
1340                                 oidset_insert(common, &oid);
1341                                 commit = lookup_commit(the_repository, &oid);
1342                                 if (negotiator)
1343                                         negotiator->ack(negotiator, commit);
1344                         }
1345                         continue;
1346                 }
1347
1348                 if (!strcmp(reader->line, "ready")) {
1349                         received_ready = 1;
1350                         continue;
1351                 }
1352
1353                 die(_("unexpected acknowledgment line: '%s'"), reader->line);
1354         }
1355
1356         if (reader->status != PACKET_READ_FLUSH &&
1357             reader->status != PACKET_READ_DELIM)
1358                 die(_("error processing acks: %d"), reader->status);
1359
1360         /*
1361          * If an "acknowledgments" section is sent, a packfile is sent if and
1362          * only if "ready" was sent in this section. The other sections
1363          * ("shallow-info" and "wanted-refs") are sent only if a packfile is
1364          * sent. Therefore, a DELIM is expected if "ready" is sent, and a FLUSH
1365          * otherwise.
1366          */
1367         if (received_ready && reader->status != PACKET_READ_DELIM)
1368                 die(_("expected packfile to be sent after 'ready'"));
1369         if (!received_ready && reader->status != PACKET_READ_FLUSH)
1370                 die(_("expected no other sections to be sent after no 'ready'"));
1371
1372         return received_ready ? READY :
1373                 (received_ack ? COMMON_FOUND : NO_COMMON_FOUND);
1374 }
1375
1376 static void receive_shallow_info(struct fetch_pack_args *args,
1377                                  struct packet_reader *reader,
1378                                  struct oid_array *shallows,
1379                                  struct shallow_info *si)
1380 {
1381         int unshallow_received = 0;
1382
1383         process_section_header(reader, "shallow-info", 0);
1384         while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
1385                 const char *arg;
1386                 struct object_id oid;
1387
1388                 if (skip_prefix(reader->line, "shallow ", &arg)) {
1389                         if (get_oid_hex(arg, &oid))
1390                                 die(_("invalid shallow line: %s"), reader->line);
1391                         oid_array_append(shallows, &oid);
1392                         continue;
1393                 }
1394                 if (skip_prefix(reader->line, "unshallow ", &arg)) {
1395                         if (get_oid_hex(arg, &oid))
1396                                 die(_("invalid unshallow line: %s"), reader->line);
1397                         if (!lookup_object(the_repository, &oid))
1398                                 die(_("object not found: %s"), reader->line);
1399                         /* make sure that it is parsed as shallow */
1400                         if (!parse_object(the_repository, &oid))
1401                                 die(_("error in object: %s"), reader->line);
1402                         if (unregister_shallow(&oid))
1403                                 die(_("no shallow found: %s"), reader->line);
1404                         unshallow_received = 1;
1405                         continue;
1406                 }
1407                 die(_("expected shallow/unshallow, got %s"), reader->line);
1408         }
1409
1410         if (reader->status != PACKET_READ_FLUSH &&
1411             reader->status != PACKET_READ_DELIM)
1412                 die(_("error processing shallow info: %d"), reader->status);
1413
1414         if (args->deepen || unshallow_received) {
1415                 /*
1416                  * Treat these as shallow lines caused by our depth settings.
1417                  * In v0, these lines cannot cause refs to be rejected; do the
1418                  * same.
1419                  */
1420                 int i;
1421
1422                 for (i = 0; i < shallows->nr; i++)
1423                         register_shallow(the_repository, &shallows->oid[i]);
1424                 setup_alternate_shallow(&shallow_lock, &alternate_shallow_file,
1425                                         NULL);
1426                 args->deepen = 1;
1427         } else if (shallows->nr) {
1428                 /*
1429                  * Treat these as shallow lines caused by the remote being
1430                  * shallow. In v0, remote refs that reach these objects are
1431                  * rejected (unless --update-shallow is set); do the same.
1432                  */
1433                 prepare_shallow_info(si, shallows);
1434                 if (si->nr_ours || si->nr_theirs)
1435                         alternate_shallow_file =
1436                                 setup_temporary_shallow(si->shallow);
1437                 else
1438                         alternate_shallow_file = NULL;
1439         } else {
1440                 alternate_shallow_file = NULL;
1441         }
1442 }
1443
1444 static int cmp_name_ref(const void *name, const void *ref)
1445 {
1446         return strcmp(name, (*(struct ref **)ref)->name);
1447 }
1448
1449 static void receive_wanted_refs(struct packet_reader *reader,
1450                                 struct ref **sought, int nr_sought)
1451 {
1452         process_section_header(reader, "wanted-refs", 0);
1453         while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
1454                 struct object_id oid;
1455                 const char *end;
1456                 struct ref **found;
1457
1458                 if (parse_oid_hex(reader->line, &oid, &end) || *end++ != ' ')
1459                         die(_("expected wanted-ref, got '%s'"), reader->line);
1460
1461                 found = bsearch(end, sought, nr_sought, sizeof(*sought),
1462                                 cmp_name_ref);
1463                 if (!found)
1464                         die(_("unexpected wanted-ref: '%s'"), reader->line);
1465                 oidcpy(&(*found)->old_oid, &oid);
1466         }
1467
1468         if (reader->status != PACKET_READ_DELIM)
1469                 die(_("error processing wanted refs: %d"), reader->status);
1470 }
1471
1472 static void receive_packfile_uris(struct packet_reader *reader,
1473                                   struct string_list *uris)
1474 {
1475         process_section_header(reader, "packfile-uris", 0);
1476         while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
1477                 if (reader->pktlen < the_hash_algo->hexsz ||
1478                     reader->line[the_hash_algo->hexsz] != ' ')
1479                         die("expected '<hash> <uri>', got: %s\n", reader->line);
1480
1481                 string_list_append(uris, reader->line);
1482         }
1483         if (reader->status != PACKET_READ_DELIM)
1484                 die("expected DELIM");
1485 }
1486
1487 enum fetch_state {
1488         FETCH_CHECK_LOCAL = 0,
1489         FETCH_SEND_REQUEST,
1490         FETCH_PROCESS_ACKS,
1491         FETCH_GET_PACK,
1492         FETCH_DONE,
1493 };
1494
1495 static void do_check_stateless_delimiter(const struct fetch_pack_args *args,
1496                                          struct packet_reader *reader)
1497 {
1498         check_stateless_delimiter(args->stateless_rpc, reader,
1499                                   _("git fetch-pack: expected response end packet"));
1500 }
1501
1502 static struct ref *do_fetch_pack_v2(struct fetch_pack_args *args,
1503                                     int fd[2],
1504                                     const struct ref *orig_ref,
1505                                     struct ref **sought, int nr_sought,
1506                                     struct oid_array *shallows,
1507                                     struct shallow_info *si,
1508                                     struct string_list *pack_lockfiles)
1509 {
1510         struct repository *r = the_repository;
1511         struct ref *ref = copy_ref_list(orig_ref);
1512         enum fetch_state state = FETCH_CHECK_LOCAL;
1513         struct oidset common = OIDSET_INIT;
1514         struct packet_reader reader;
1515         int in_vain = 0, negotiation_started = 0;
1516         int haves_to_send = INITIAL_FLUSH;
1517         struct fetch_negotiator negotiator_alloc;
1518         struct fetch_negotiator *negotiator;
1519         int seen_ack = 0;
1520         struct string_list packfile_uris = STRING_LIST_INIT_DUP;
1521         int i;
1522
1523         negotiator = &negotiator_alloc;
1524         fetch_negotiator_init(r, negotiator);
1525
1526         packet_reader_init(&reader, fd[0], NULL, 0,
1527                            PACKET_READ_CHOMP_NEWLINE |
1528                            PACKET_READ_DIE_ON_ERR_PACKET);
1529         if (git_env_bool("GIT_TEST_SIDEBAND_ALL", 1) &&
1530             server_supports_feature("fetch", "sideband-all", 0)) {
1531                 reader.use_sideband = 1;
1532                 reader.me = "fetch-pack";
1533         }
1534
1535         while (state != FETCH_DONE) {
1536                 switch (state) {
1537                 case FETCH_CHECK_LOCAL:
1538                         sort_ref_list(&ref, ref_compare_name);
1539                         QSORT(sought, nr_sought, cmp_ref_by_name);
1540
1541                         /* v2 supports these by default */
1542                         allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
1543                         use_sideband = 2;
1544                         if (args->depth > 0 || args->deepen_since || args->deepen_not)
1545                                 args->deepen = 1;
1546
1547                         /* Filter 'ref' by 'sought' and those that aren't local */
1548                         mark_complete_and_common_ref(negotiator, args, &ref);
1549                         filter_refs(args, &ref, sought, nr_sought);
1550                         if (everything_local(args, &ref))
1551                                 state = FETCH_DONE;
1552                         else
1553                                 state = FETCH_SEND_REQUEST;
1554
1555                         mark_tips(negotiator, args->negotiation_tips);
1556                         for_each_cached_alternate(negotiator,
1557                                                   insert_one_alternate_object);
1558                         break;
1559                 case FETCH_SEND_REQUEST:
1560                         if (!negotiation_started) {
1561                                 negotiation_started = 1;
1562                                 trace2_region_enter("fetch-pack",
1563                                                     "negotiation_v2",
1564                                                     the_repository);
1565                         }
1566                         if (send_fetch_request(negotiator, fd[1], args, ref,
1567                                                &common,
1568                                                &haves_to_send, &in_vain,
1569                                                reader.use_sideband,
1570                                                seen_ack))
1571                                 state = FETCH_GET_PACK;
1572                         else
1573                                 state = FETCH_PROCESS_ACKS;
1574                         break;
1575                 case FETCH_PROCESS_ACKS:
1576                         /* Process ACKs/NAKs */
1577                         switch (process_acks(negotiator, &reader, &common)) {
1578                         case READY:
1579                                 /*
1580                                  * Don't check for response delimiter; get_pack() will
1581                                  * read the rest of this response.
1582                                  */
1583                                 state = FETCH_GET_PACK;
1584                                 break;
1585                         case COMMON_FOUND:
1586                                 in_vain = 0;
1587                                 seen_ack = 1;
1588                                 /* fallthrough */
1589                         case NO_COMMON_FOUND:
1590                                 do_check_stateless_delimiter(args, &reader);
1591                                 state = FETCH_SEND_REQUEST;
1592                                 break;
1593                         }
1594                         break;
1595                 case FETCH_GET_PACK:
1596                         trace2_region_leave("fetch-pack",
1597                                             "negotiation_v2",
1598                                             the_repository);
1599                         /* Check for shallow-info section */
1600                         if (process_section_header(&reader, "shallow-info", 1))
1601                                 receive_shallow_info(args, &reader, shallows, si);
1602
1603                         if (process_section_header(&reader, "wanted-refs", 1))
1604                                 receive_wanted_refs(&reader, sought, nr_sought);
1605
1606                         /* get the pack(s) */
1607                         if (process_section_header(&reader, "packfile-uris", 1))
1608                                 receive_packfile_uris(&reader, &packfile_uris);
1609                         process_section_header(&reader, "packfile", 0);
1610                         if (get_pack(args, fd, pack_lockfiles,
1611                                      !packfile_uris.nr, sought, nr_sought))
1612                                 die(_("git fetch-pack: fetch failed."));
1613                         do_check_stateless_delimiter(args, &reader);
1614
1615                         state = FETCH_DONE;
1616                         break;
1617                 case FETCH_DONE:
1618                         continue;
1619                 }
1620         }
1621
1622         for (i = 0; i < packfile_uris.nr; i++) {
1623                 struct child_process cmd = CHILD_PROCESS_INIT;
1624                 char packname[GIT_MAX_HEXSZ + 1];
1625                 const char *uri = packfile_uris.items[i].string +
1626                         the_hash_algo->hexsz + 1;
1627
1628                 strvec_push(&cmd.args, "http-fetch");
1629                 strvec_pushf(&cmd.args, "--packfile=%.*s",
1630                              (int) the_hash_algo->hexsz,
1631                              packfile_uris.items[i].string);
1632                 strvec_push(&cmd.args, uri);
1633                 cmd.git_cmd = 1;
1634                 cmd.no_stdin = 1;
1635                 cmd.out = -1;
1636                 if (start_command(&cmd))
1637                         die("fetch-pack: unable to spawn http-fetch");
1638
1639                 if (read_in_full(cmd.out, packname, 5) < 0 ||
1640                     memcmp(packname, "keep\t", 5))
1641                         die("fetch-pack: expected keep then TAB at start of http-fetch output");
1642
1643                 if (read_in_full(cmd.out, packname,
1644                                  the_hash_algo->hexsz + 1) < 0 ||
1645                     packname[the_hash_algo->hexsz] != '\n')
1646                         die("fetch-pack: expected hash then LF at end of http-fetch output");
1647
1648                 packname[the_hash_algo->hexsz] = '\0';
1649
1650                 close(cmd.out);
1651
1652                 if (finish_command(&cmd))
1653                         die("fetch-pack: unable to finish http-fetch");
1654
1655                 if (memcmp(packfile_uris.items[i].string, packname,
1656                            the_hash_algo->hexsz))
1657                         die("fetch-pack: pack downloaded from %s does not match expected hash %.*s",
1658                             uri, (int) the_hash_algo->hexsz,
1659                             packfile_uris.items[i].string);
1660
1661                 string_list_append_nodup(pack_lockfiles,
1662                                          xstrfmt("%s/pack/pack-%s.keep",
1663                                                  get_object_directory(),
1664                                                  packname));
1665         }
1666         string_list_clear(&packfile_uris, 0);
1667
1668         if (negotiator)
1669                 negotiator->release(negotiator);
1670
1671         oidset_clear(&common);
1672         return ref;
1673 }
1674
1675 static int fetch_pack_config_cb(const char *var, const char *value, void *cb)
1676 {
1677         if (strcmp(var, "fetch.fsck.skiplist") == 0) {
1678                 const char *path;
1679
1680                 if (git_config_pathname(&path, var, value))
1681                         return 1;
1682                 strbuf_addf(&fsck_msg_types, "%cskiplist=%s",
1683                         fsck_msg_types.len ? ',' : '=', path);
1684                 free((char *)path);
1685                 return 0;
1686         }
1687
1688         if (skip_prefix(var, "fetch.fsck.", &var)) {
1689                 if (is_valid_msg_type(var, value))
1690                         strbuf_addf(&fsck_msg_types, "%c%s=%s",
1691                                 fsck_msg_types.len ? ',' : '=', var, value);
1692                 else
1693                         warning("Skipping unknown msg id '%s'", var);
1694                 return 0;
1695         }
1696
1697         return git_default_config(var, value, cb);
1698 }
1699
1700 static void fetch_pack_config(void)
1701 {
1702         git_config_get_int("fetch.unpacklimit", &fetch_unpack_limit);
1703         git_config_get_int("transfer.unpacklimit", &transfer_unpack_limit);
1704         git_config_get_bool("repack.usedeltabaseoffset", &prefer_ofs_delta);
1705         git_config_get_bool("fetch.fsckobjects", &fetch_fsck_objects);
1706         git_config_get_bool("transfer.fsckobjects", &transfer_fsck_objects);
1707         if (!uri_protocols.nr) {
1708                 char *str;
1709
1710                 if (!git_config_get_string("fetch.uriprotocols", &str) && str) {
1711                         string_list_split(&uri_protocols, str, ',', -1);
1712                         free(str);
1713                 }
1714         }
1715
1716         git_config(fetch_pack_config_cb, NULL);
1717 }
1718
1719 static void fetch_pack_setup(void)
1720 {
1721         static int did_setup;
1722         if (did_setup)
1723                 return;
1724         fetch_pack_config();
1725         if (0 <= transfer_unpack_limit)
1726                 unpack_limit = transfer_unpack_limit;
1727         else if (0 <= fetch_unpack_limit)
1728                 unpack_limit = fetch_unpack_limit;
1729         did_setup = 1;
1730 }
1731
1732 static int remove_duplicates_in_refs(struct ref **ref, int nr)
1733 {
1734         struct string_list names = STRING_LIST_INIT_NODUP;
1735         int src, dst;
1736
1737         for (src = dst = 0; src < nr; src++) {
1738                 struct string_list_item *item;
1739                 item = string_list_insert(&names, ref[src]->name);
1740                 if (item->util)
1741                         continue; /* already have it */
1742                 item->util = ref[src];
1743                 if (src != dst)
1744                         ref[dst] = ref[src];
1745                 dst++;
1746         }
1747         for (src = dst; src < nr; src++)
1748                 ref[src] = NULL;
1749         string_list_clear(&names, 0);
1750         return dst;
1751 }
1752
1753 static void update_shallow(struct fetch_pack_args *args,
1754                            struct ref **sought, int nr_sought,
1755                            struct shallow_info *si)
1756 {
1757         struct oid_array ref = OID_ARRAY_INIT;
1758         int *status;
1759         int i;
1760
1761         if (args->deepen && alternate_shallow_file) {
1762                 if (*alternate_shallow_file == '\0') { /* --unshallow */
1763                         unlink_or_warn(git_path_shallow(the_repository));
1764                         rollback_shallow_file(the_repository, &shallow_lock);
1765                 } else
1766                         commit_shallow_file(the_repository, &shallow_lock);
1767                 alternate_shallow_file = NULL;
1768                 return;
1769         }
1770
1771         if (!si->shallow || !si->shallow->nr)
1772                 return;
1773
1774         if (args->cloning) {
1775                 /*
1776                  * remote is shallow, but this is a clone, there are
1777                  * no objects in repo to worry about. Accept any
1778                  * shallow points that exist in the pack (iow in repo
1779                  * after get_pack() and reprepare_packed_git())
1780                  */
1781                 struct oid_array extra = OID_ARRAY_INIT;
1782                 struct object_id *oid = si->shallow->oid;
1783                 for (i = 0; i < si->shallow->nr; i++)
1784                         if (has_object_file(&oid[i]))
1785                                 oid_array_append(&extra, &oid[i]);
1786                 if (extra.nr) {
1787                         setup_alternate_shallow(&shallow_lock,
1788                                                 &alternate_shallow_file,
1789                                                 &extra);
1790                         commit_shallow_file(the_repository, &shallow_lock);
1791                         alternate_shallow_file = NULL;
1792                 }
1793                 oid_array_clear(&extra);
1794                 return;
1795         }
1796
1797         if (!si->nr_ours && !si->nr_theirs)
1798                 return;
1799
1800         remove_nonexistent_theirs_shallow(si);
1801         if (!si->nr_ours && !si->nr_theirs)
1802                 return;
1803         for (i = 0; i < nr_sought; i++)
1804                 oid_array_append(&ref, &sought[i]->old_oid);
1805         si->ref = &ref;
1806
1807         if (args->update_shallow) {
1808                 /*
1809                  * remote is also shallow, .git/shallow may be updated
1810                  * so all refs can be accepted. Make sure we only add
1811                  * shallow roots that are actually reachable from new
1812                  * refs.
1813                  */
1814                 struct oid_array extra = OID_ARRAY_INIT;
1815                 struct object_id *oid = si->shallow->oid;
1816                 assign_shallow_commits_to_refs(si, NULL, NULL);
1817                 if (!si->nr_ours && !si->nr_theirs) {
1818                         oid_array_clear(&ref);
1819                         return;
1820                 }
1821                 for (i = 0; i < si->nr_ours; i++)
1822                         oid_array_append(&extra, &oid[si->ours[i]]);
1823                 for (i = 0; i < si->nr_theirs; i++)
1824                         oid_array_append(&extra, &oid[si->theirs[i]]);
1825                 setup_alternate_shallow(&shallow_lock,
1826                                         &alternate_shallow_file,
1827                                         &extra);
1828                 commit_shallow_file(the_repository, &shallow_lock);
1829                 oid_array_clear(&extra);
1830                 oid_array_clear(&ref);
1831                 alternate_shallow_file = NULL;
1832                 return;
1833         }
1834
1835         /*
1836          * remote is also shallow, check what ref is safe to update
1837          * without updating .git/shallow
1838          */
1839         status = xcalloc(nr_sought, sizeof(*status));
1840         assign_shallow_commits_to_refs(si, NULL, status);
1841         if (si->nr_ours || si->nr_theirs) {
1842                 for (i = 0; i < nr_sought; i++)
1843                         if (status[i])
1844                                 sought[i]->status = REF_STATUS_REJECT_SHALLOW;
1845         }
1846         free(status);
1847         oid_array_clear(&ref);
1848 }
1849
1850 static int iterate_ref_map(void *cb_data, struct object_id *oid)
1851 {
1852         struct ref **rm = cb_data;
1853         struct ref *ref = *rm;
1854
1855         if (!ref)
1856                 return -1; /* end of the list */
1857         *rm = ref->next;
1858         oidcpy(oid, &ref->old_oid);
1859         return 0;
1860 }
1861
1862 struct ref *fetch_pack(struct fetch_pack_args *args,
1863                        int fd[],
1864                        const struct ref *ref,
1865                        struct ref **sought, int nr_sought,
1866                        struct oid_array *shallow,
1867                        struct string_list *pack_lockfiles,
1868                        enum protocol_version version)
1869 {
1870         struct ref *ref_cpy;
1871         struct shallow_info si;
1872         struct oid_array shallows_scratch = OID_ARRAY_INIT;
1873
1874         fetch_pack_setup();
1875         if (nr_sought)
1876                 nr_sought = remove_duplicates_in_refs(sought, nr_sought);
1877
1878         if (version != protocol_v2 && !ref) {
1879                 packet_flush(fd[1]);
1880                 die(_("no matching remote head"));
1881         }
1882         if (version == protocol_v2) {
1883                 if (shallow->nr)
1884                         BUG("Protocol V2 does not provide shallows at this point in the fetch");
1885                 memset(&si, 0, sizeof(si));
1886                 ref_cpy = do_fetch_pack_v2(args, fd, ref, sought, nr_sought,
1887                                            &shallows_scratch, &si,
1888                                            pack_lockfiles);
1889         } else {
1890                 prepare_shallow_info(&si, shallow);
1891                 ref_cpy = do_fetch_pack(args, fd, ref, sought, nr_sought,
1892                                         &si, pack_lockfiles);
1893         }
1894         reprepare_packed_git(the_repository);
1895
1896         if (!args->cloning && args->deepen) {
1897                 struct check_connected_options opt = CHECK_CONNECTED_INIT;
1898                 struct ref *iterator = ref_cpy;
1899                 opt.shallow_file = alternate_shallow_file;
1900                 if (args->deepen)
1901                         opt.is_deepening_fetch = 1;
1902                 if (check_connected(iterate_ref_map, &iterator, &opt)) {
1903                         error(_("remote did not send all necessary objects"));
1904                         free_refs(ref_cpy);
1905                         ref_cpy = NULL;
1906                         rollback_shallow_file(the_repository, &shallow_lock);
1907                         goto cleanup;
1908                 }
1909                 args->connectivity_checked = 1;
1910         }
1911
1912         update_shallow(args, sought, nr_sought, &si);
1913 cleanup:
1914         clear_shallow_info(&si);
1915         oid_array_clear(&shallows_scratch);
1916         return ref_cpy;
1917 }
1918
1919 int report_unmatched_refs(struct ref **sought, int nr_sought)
1920 {
1921         int i, ret = 0;
1922
1923         for (i = 0; i < nr_sought; i++) {
1924                 if (!sought[i])
1925                         continue;
1926                 switch (sought[i]->match_status) {
1927                 case REF_MATCHED:
1928                         continue;
1929                 case REF_NOT_MATCHED:
1930                         error(_("no such remote ref %s"), sought[i]->name);
1931                         break;
1932                 case REF_UNADVERTISED_NOT_ALLOWED:
1933                         error(_("Server does not allow request for unadvertised object %s"),
1934                               sought[i]->name);
1935                         break;
1936                 }
1937                 ret = 1;
1938         }
1939         return ret;
1940 }