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 int rev_list_insert_ref(struct fetch_negotiator *negotiator,
 112                                const char *refname,
 113                                const struct object_id *oid)
 114 {
 115         struct object *o = deref_tag(the_repository,
 116                                      parse_object(the_repository, oid),
 117                                      refname, 0);
 118
 119         if (o && o->type == OBJ_COMMIT)
 120                 negotiator->add_tip(negotiator, (struct commit *)o);
 121
 122         return 0;
 123 }
 124
 125 static int rev_list_insert_ref_oid(const char *refname, const struct object_id *oid,
 126                                    int flag, void *cb_data)
 127 {
 128         return rev_list_insert_ref(cb_data, refname, oid);
 129 }
 130
 131 enum ack_type {
 132         NAK = 0,
 133         ACK,
 134         ACK_continue,
 135         ACK_common,
 136         ACK_ready
 137 };
 138
 139 static void consume_shallow_list(struct fetch_pack_args *args,
 140                                  struct packet_reader *reader)
 141 {
 142         if (args->stateless_rpc && args->deepen) {
 143                 /* If we sent a depth we will get back "duplicate"
 144                  * shallow and unshallow commands every time there
 145                  * is a block of have lines exchanged.
 146                  */
 147                 while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
 148                         if (starts_with(reader->line, "shallow "))
 149                                 continue;
 150                         if (starts_with(reader->line, "unshallow "))
 151                                 continue;
 152                         die(_("git fetch-pack: expected shallow list"));
 153                 }
 154                 if (reader->status != PACKET_READ_FLUSH)
 155                         die(_("git fetch-pack: expected a flush packet after shallow list"));
 156         }
 157 }
 158
 159 static enum ack_type get_ack(struct packet_reader *reader,
 160                              struct object_id *result_oid)
 161 {
 162         int len;
 163         const char *arg;
 164
 165         if (packet_reader_read(reader) != PACKET_READ_NORMAL)
 166                 die(_("git fetch-pack: expected ACK/NAK, got a flush packet"));
 167         len = reader->pktlen;
 168
 169         if (!strcmp(reader->line, "NAK"))
 170                 return NAK;
 171         if (skip_prefix(reader->line, "ACK ", &arg)) {
 172                 const char *p;
 173                 if (!parse_oid_hex(arg, result_oid, &p)) {
 174                         len -= p - reader->line;
 175                         if (len < 1)
 176                                 return ACK;
 177                         if (strstr(p, "continue"))
 178                                 return ACK_continue;
 179                         if (strstr(p, "common"))
 180                                 return ACK_common;
 181                         if (strstr(p, "ready"))
 182                                 return ACK_ready;
 183                         return ACK;
 184                 }
 185         }
 186         die(_("git fetch-pack: expected ACK/NAK, got '%s'"), reader->line);
 187 }
 188
 189 static void send_request(struct fetch_pack_args *args,
 190                          int fd, struct strbuf *buf)
 191 {
 192         if (args->stateless_rpc) {
 193                 send_sideband(fd, -1, buf->buf, buf->len, LARGE_PACKET_MAX);
 194                 packet_flush(fd);
 195         } else {
 196                 if (write_in_full(fd, buf->buf, buf->len) < 0)
 197                         die_errno(_("unable to write to remote"));
 198         }
 199 }
 200
 201 static void insert_one_alternate_object(struct fetch_negotiator *negotiator,
 202                                         struct object *obj)
 203 {
 204         rev_list_insert_ref(negotiator, NULL, &obj->oid);
 205 }
 206
 207 #define INITIAL_FLUSH 16
 208 #define PIPESAFE_FLUSH 32
 209 #define LARGE_FLUSH 16384
 210
 211 static int next_flush(int stateless_rpc, int count)
 212 {
 213         if (stateless_rpc) {
 214                 if (count < LARGE_FLUSH)
 215                         count <<= 1;
 216                 else
 217                         count = count * 11 / 10;
 218         } else {
 219                 if (count < PIPESAFE_FLUSH)
 220                         count <<= 1;
 221                 else
 222                         count += PIPESAFE_FLUSH;
 223         }
 224         return count;
 225 }
 226
 227 static void mark_tips(struct fetch_negotiator *negotiator,
 228                       const struct oid_array *negotiation_tips)
 229 {
 230         int i;
 231
 232         if (!negotiation_tips) {
 233                 for_each_ref(rev_list_insert_ref_oid, negotiator);
 234                 return;
 235         }
 236
 237         for (i = 0; i < negotiation_tips->nr; i++)
 238                 rev_list_insert_ref(negotiator, NULL,
 239                                     &negotiation_tips->oid[i]);
 240         return;
 241 }
 242
 243 static int find_common(struct fetch_negotiator *negotiator,
 244                        struct fetch_pack_args *args,
 245                        int fd[2], struct object_id *result_oid,
 246                        struct ref *refs)
 247 {
 248         int fetching;
 249         int count = 0, flushes = 0, flush_at = INITIAL_FLUSH, retval;
 250         const struct object_id *oid;
 251         unsigned in_vain = 0;
 252         int got_continue = 0;
 253         int got_ready = 0;
 254         struct strbuf req_buf = STRBUF_INIT;
 255         size_t state_len = 0;
 256         struct packet_reader reader;
 257
 258         if (args->stateless_rpc && multi_ack == 1)
 259                 die(_("--stateless-rpc requires multi_ack_detailed"));
 260
 261         packet_reader_init(&reader, fd[0], NULL, 0,
 262                            PACKET_READ_CHOMP_NEWLINE |
 263                            PACKET_READ_DIE_ON_ERR_PACKET);
 264
 265         if (!args->no_dependents) {
 266                 mark_tips(negotiator, args->negotiation_tips);
 267                 for_each_cached_alternate(negotiator, insert_one_alternate_object);
 268         }
 269
 270         fetching = 0;
 271         for ( ; refs ; refs = refs->next) {
 272                 struct object_id *remote = &refs->old_oid;
 273                 const char *remote_hex;
 274                 struct object *o;
 275
 276                 /*
 277                  * If that object is complete (i.e. it is an ancestor of a
 278                  * local ref), we tell them we have it but do not have to
 279                  * tell them about its ancestors, which they already know
 280                  * about.
 281                  *
 282                  * We use lookup_object here because we are only
 283                  * interested in the case we *know* the object is
 284                  * reachable and we have already scanned it.
 285                  *
 286                  * Do this only if args->no_dependents is false (if it is true,
 287                  * we cannot trust the object flags).
 288                  */
 289                 if (!args->no_dependents &&
 290                     ((o = lookup_object(the_repository, remote)) != NULL) &&
 291                                 (o->flags & COMPLETE)) {
 292                         continue;
 293                 }
 294
 295                 remote_hex = oid_to_hex(remote);
 296                 if (!fetching) {
 297                         struct strbuf c = STRBUF_INIT;
 298                         if (multi_ack == 2)     strbuf_addstr(&c, " multi_ack_detailed");
 299                         if (multi_ack == 1)     strbuf_addstr(&c, " multi_ack");
 300                         if (no_done)            strbuf_addstr(&c, " no-done");
 301                         if (use_sideband == 2)  strbuf_addstr(&c, " side-band-64k");
 302                         if (use_sideband == 1)  strbuf_addstr(&c, " side-band");
 303                         if (args->deepen_relative) strbuf_addstr(&c, " deepen-relative");
 304                         if (args->use_thin_pack) strbuf_addstr(&c, " thin-pack");
 305                         if (args->no_progress)   strbuf_addstr(&c, " no-progress");
 306                         if (args->include_tag)   strbuf_addstr(&c, " include-tag");
 307                         if (prefer_ofs_delta)   strbuf_addstr(&c, " ofs-delta");
 308                         if (deepen_since_ok)    strbuf_addstr(&c, " deepen-since");
 309                         if (deepen_not_ok)      strbuf_addstr(&c, " deepen-not");
 310                         if (agent_supported)    strbuf_addf(&c, " agent=%s",
 311                                                             git_user_agent_sanitized());
 312                         if (args->filter_options.choice)
 313                                 strbuf_addstr(&c, " filter");
 314                         packet_buf_write(&req_buf, "want %s%s\n", remote_hex, c.buf);
 315                         strbuf_release(&c);
 316                 } else
 317                         packet_buf_write(&req_buf, "want %s\n", remote_hex);
 318                 fetching++;
 319         }
 320
 321         if (!fetching) {
 322                 strbuf_release(&req_buf);
 323                 packet_flush(fd[1]);
 324                 return 1;
 325         }
 326
 327         if (is_repository_shallow(the_repository))
 328                 write_shallow_commits(&req_buf, 1, NULL);
 329         if (args->depth > 0)
 330                 packet_buf_write(&req_buf, "deepen %d", args->depth);
 331         if (args->deepen_since) {
 332                 timestamp_t max_age = approxidate(args->deepen_since);
 333                 packet_buf_write(&req_buf, "deepen-since %"PRItime, max_age);
 334         }
 335         if (args->deepen_not) {
 336                 int i;
 337                 for (i = 0; i < args->deepen_not->nr; i++) {
 338                         struct string_list_item *s = args->deepen_not->items + i;
 339                         packet_buf_write(&req_buf, "deepen-not %s", s->string);
 340                 }
 341         }
 342         if (server_supports_filtering && args->filter_options.choice) {
 343                 const char *spec =
 344                         expand_list_objects_filter_spec(&args->filter_options);
 345                 packet_buf_write(&req_buf, "filter %s", spec);
 346         }
 347         packet_buf_flush(&req_buf);
 348         state_len = req_buf.len;
 349
 350         if (args->deepen) {
 351                 const char *arg;
 352                 struct object_id oid;
 353
 354                 send_request(args, fd[1], &req_buf);
 355                 while (packet_reader_read(&reader) == PACKET_READ_NORMAL) {
 356                         if (skip_prefix(reader.line, "shallow ", &arg)) {
 357                                 if (get_oid_hex(arg, &oid))
 358                                         die(_("invalid shallow line: %s"), reader.line);
 359                                 register_shallow(the_repository, &oid);
 360                                 continue;
 361                         }
 362                         if (skip_prefix(reader.line, "unshallow ", &arg)) {
 363                                 if (get_oid_hex(arg, &oid))
 364                                         die(_("invalid unshallow line: %s"), reader.line);
 365                                 if (!lookup_object(the_repository, &oid))
 366                                         die(_("object not found: %s"), reader.line);
 367                                 /* make sure that it is parsed as shallow */
 368                                 if (!parse_object(the_repository, &oid))
 369                                         die(_("error in object: %s"), reader.line);
 370                                 if (unregister_shallow(&oid))
 371                                         die(_("no shallow found: %s"), reader.line);
 372                                 continue;
 373                         }
 374                         die(_("expected shallow/unshallow, got %s"), reader.line);
 375                 }
 376         } else if (!args->stateless_rpc)
 377                 send_request(args, fd[1], &req_buf);
 378
 379         if (!args->stateless_rpc) {
 380                 /* If we aren't using the stateless-rpc interface
 381                  * we don't need to retain the headers.
 382                  */
 383                 strbuf_setlen(&req_buf, 0);
 384                 state_len = 0;
 385         }
 386
 387         trace2_region_enter("fetch-pack", "negotiation_v0_v1", the_repository);
 388         flushes = 0;
 389         retval = -1;
 390         if (args->no_dependents)
 391                 goto done;
 392         while ((oid = negotiator->next(negotiator))) {
 393                 packet_buf_write(&req_buf, "have %s\n", oid_to_hex(oid));
 394                 print_verbose(args, "have %s", oid_to_hex(oid));
 395                 in_vain++;
 396                 if (flush_at <= ++count) {
 397                         int ack;
 398
 399                         packet_buf_flush(&req_buf);
 400                         send_request(args, fd[1], &req_buf);
 401                         strbuf_setlen(&req_buf, state_len);
 402                         flushes++;
 403                         flush_at = next_flush(args->stateless_rpc, count);
 404
 405                         /*
 406                          * We keep one window "ahead" of the other side, and
 407                          * will wait for an ACK only on the next one
 408                          */
 409                         if (!args->stateless_rpc && count == INITIAL_FLUSH)
 410                                 continue;
 411
 412                         consume_shallow_list(args, &reader);
 413                         do {
 414                                 ack = get_ack(&reader, result_oid);
 415                                 if (ack)
 416                                         print_verbose(args, _("got %s %d %s"), "ack",
 417                                                       ack, oid_to_hex(result_oid));
 418                                 switch (ack) {
 419                                 case ACK:
 420                                         flushes = 0;
 421                                         multi_ack = 0;
 422                                         retval = 0;
 423                                         goto done;
 424                                 case ACK_common:
 425                                 case ACK_ready:
 426                                 case ACK_continue: {
 427                                         struct commit *commit =
 428                                                 lookup_commit(the_repository,
 429                                                               result_oid);
 430                                         int was_common;
 431
 432                                         if (!commit)
 433                                                 die(_("invalid commit %s"), oid_to_hex(result_oid));
 434                                         was_common = negotiator->ack(negotiator, commit);
 435                                         if (args->stateless_rpc
 436                                          && ack == ACK_common
 437                                          && !was_common) {
 438                                                 /* We need to replay the have for this object
 439                                                  * on the next RPC request so the peer knows
 440                                                  * it is in common with us.
 441                                                  */
 442                                                 const char *hex = oid_to_hex(result_oid);
 443                                                 packet_buf_write(&req_buf, "have %s\n", hex);
 444                                                 state_len = req_buf.len;
 445                                                 /*
 446                                                  * Reset in_vain because an ack
 447                                                  * for this commit has not been
 448                                                  * seen.
 449                                                  */
 450                                                 in_vain = 0;
 451                                         } else if (!args->stateless_rpc
 452                                                    || ack != ACK_common)
 453                                                 in_vain = 0;
 454                                         retval = 0;
 455                                         got_continue = 1;
 456                                         if (ack == ACK_ready)
 457                                                 got_ready = 1;
 458                                         break;
 459                                         }
 460                                 }
 461                         } while (ack);
 462                         flushes--;
 463                         if (got_continue && MAX_IN_VAIN < in_vain) {
 464                                 print_verbose(args, _("giving up"));
 465                                 break; /* give up */
 466                         }
 467                         if (got_ready)
 468                                 break;
 469                 }
 470         }
 471 done:
 472         trace2_region_leave("fetch-pack", "negotiation_v0_v1", the_repository);
 473         if (!got_ready || !no_done) {
 474                 packet_buf_write(&req_buf, "done\n");
 475                 send_request(args, fd[1], &req_buf);
 476         }
 477         print_verbose(args, _("done"));
 478         if (retval != 0) {
 479                 multi_ack = 0;
 480                 flushes++;
 481         }
 482         strbuf_release(&req_buf);
 483
 484         if (!got_ready || !no_done)
 485                 consume_shallow_list(args, &reader);
 486         while (flushes || multi_ack) {
 487                 int ack = get_ack(&reader, result_oid);
 488                 if (ack) {
 489                         print_verbose(args, _("got %s (%d) %s"), "ack",
 490                                       ack, oid_to_hex(result_oid));
 491                         if (ack == ACK)
 492                                 return 0;
 493                         multi_ack = 1;
 494                         continue;
 495                 }
 496                 flushes--;
 497         }
 498         /* it is no error to fetch into a completely empty repo */
 499         return count ? retval : 0;
 500 }
 501
 502 static struct commit_list *complete;
 503
 504 static int mark_complete(const struct object_id *oid)
 505 {
 506         struct object *o = parse_object(the_repository, oid);
 507
 508         while (o && o->type == OBJ_TAG) {
 509                 struct tag *t = (struct tag *) o;
 510                 if (!t->tagged)
 511                         break; /* broken repository */
 512                 o->flags |= COMPLETE;
 513                 o = parse_object(the_repository, &t->tagged->oid);
 514         }
 515         if (o && o->type == OBJ_COMMIT) {
 516                 struct commit *commit = (struct commit *)o;
 517                 if (!(commit->object.flags & COMPLETE)) {
 518                         commit->object.flags |= COMPLETE;
 519                         commit_list_insert(commit, &complete);
 520                 }
 521         }
 522         return 0;
 523 }
 524
 525 static int mark_complete_oid(const char *refname, const struct object_id *oid,
 526                              int flag, void *cb_data)
 527 {
 528         return mark_complete(oid);
 529 }
 530
 531 static void mark_recent_complete_commits(struct fetch_pack_args *args,
 532                                          timestamp_t cutoff)
 533 {
 534         while (complete && cutoff <= complete->item->date) {
 535                 print_verbose(args, _("Marking %s as complete"),
 536                               oid_to_hex(&complete->item->object.oid));
 537                 pop_most_recent_commit(&complete, COMPLETE);
 538         }
 539 }
 540
 541 static void add_refs_to_oidset(struct oidset *oids, struct ref *refs)
 542 {
 543         for (; refs; refs = refs->next)
 544                 oidset_insert(oids, &refs->old_oid);
 545 }
 546
 547 static int is_unmatched_ref(const struct ref *ref)
 548 {
 549         struct object_id oid;
 550         const char *p;
 551         return  ref->match_status == REF_NOT_MATCHED &&
 552                 !parse_oid_hex(ref->name, &oid, &p) &&
 553                 *p == '\0' &&
 554                 oideq(&oid, &ref->old_oid);
 555 }
 556
 557 static void filter_refs(struct fetch_pack_args *args,
 558                         struct ref **refs,
 559                         struct ref **sought, int nr_sought)
 560 {
 561         struct ref *newlist = NULL;
 562         struct ref **newtail = &newlist;
 563         struct ref *unmatched = NULL;
 564         struct ref *ref, *next;
 565         struct oidset tip_oids = OIDSET_INIT;
 566         int i;
 567         int strict = !(allow_unadvertised_object_request &
 568                        (ALLOW_TIP_SHA1 | ALLOW_REACHABLE_SHA1));
 569
 570         i = 0;
 571         for (ref = *refs; ref; ref = next) {
 572                 int keep = 0;
 573                 next = ref->next;
 574
 575                 if (starts_with(ref->name, "refs/") &&
 576                     check_refname_format(ref->name, 0)) {
 577                         /*
 578                          * trash or a peeled value; do not even add it to
 579                          * unmatched list
 580                          */
 581                         free_one_ref(ref);
 582                         continue;
 583                 } else {
 584                         while (i < nr_sought) {
 585                                 int cmp = strcmp(ref->name, sought[i]->name);
 586                                 if (cmp < 0)
 587                                         break; /* definitely do not have it */
 588                                 else if (cmp == 0) {
 589                                         keep = 1; /* definitely have it */
 590                                         sought[i]->match_status = REF_MATCHED;
 591                                 }
 592                                 i++;
 593                         }
 594
 595                         if (!keep && args->fetch_all &&
 596                             (!args->deepen || !starts_with(ref->name, "refs/tags/")))
 597                                 keep = 1;
 598                 }
 599
 600                 if (keep) {
 601                         *newtail = ref;
 602                         ref->next = NULL;
 603                         newtail = &ref->next;
 604                 } else {
 605                         ref->next = unmatched;
 606                         unmatched = ref;
 607                 }
 608         }
 609
 610         if (strict) {
 611                 for (i = 0; i < nr_sought; i++) {
 612                         ref = sought[i];
 613                         if (!is_unmatched_ref(ref))
 614                                 continue;
 615
 616                         add_refs_to_oidset(&tip_oids, unmatched);
 617                         add_refs_to_oidset(&tip_oids, newlist);
 618                         break;
 619                 }
 620         }
 621
 622         /* Append unmatched requests to the list */
 623         for (i = 0; i < nr_sought; i++) {
 624                 ref = sought[i];
 625                 if (!is_unmatched_ref(ref))
 626                         continue;
 627
 628                 if (!strict || oidset_contains(&tip_oids, &ref->old_oid)) {
 629                         ref->match_status = REF_MATCHED;
 630                         *newtail = copy_ref(ref);
 631                         newtail = &(*newtail)->next;
 632                 } else {
 633                         ref->match_status = REF_UNADVERTISED_NOT_ALLOWED;
 634                 }
 635         }
 636
 637         oidset_clear(&tip_oids);
 638         free_refs(unmatched);
 639
 640         *refs = newlist;
 641 }
 642
 643 static void mark_alternate_complete(struct fetch_negotiator *unused,
 644                                     struct object *obj)
 645 {
 646         mark_complete(&obj->oid);
 647 }
 648
 649 struct loose_object_iter {
 650         struct oidset *loose_object_set;
 651         struct ref *refs;
 652 };
 653
 654 /*
 655  * Mark recent commits available locally and reachable from a local ref as
 656  * COMPLETE. If args->no_dependents is false, also mark COMPLETE remote refs as
 657  * COMMON_REF (otherwise, we are not planning to participate in negotiation, and
 658  * thus do not need COMMON_REF marks).
 659  *
 660  * The cutoff time for recency is determined by this heuristic: it is the
 661  * earliest commit time of the objects in refs that are commits and that we know
 662  * the commit time of.
 663  */
 664 static void mark_complete_and_common_ref(struct fetch_negotiator *negotiator,
 665                                          struct fetch_pack_args *args,
 666                                          struct ref **refs)
 667 {
 668         struct ref *ref;
 669         int old_save_commit_buffer = save_commit_buffer;
 670         timestamp_t cutoff = 0;
 671
 672         save_commit_buffer = 0;
 673
 674         trace2_region_enter("fetch-pack", "parse_remote_refs_and_find_cutoff", NULL);
 675         for (ref = *refs; ref; ref = ref->next) {
 676                 struct object *o;
 677
 678                 if (!has_object_file_with_flags(&ref->old_oid,
 679                                                 OBJECT_INFO_QUICK |
 680                                                         OBJECT_INFO_SKIP_FETCH_OBJECT))
 681                         continue;
 682                 o = parse_object(the_repository, &ref->old_oid);
 683                 if (!o)
 684                         continue;
 685
 686                 /*
 687                  * We already have it -- which may mean that we were
 688                  * in sync with the other side at some time after
 689                  * that (it is OK if we guess wrong here).
 690                  */
 691                 if (o->type == OBJ_COMMIT) {
 692                         struct commit *commit = (struct commit *)o;
 693                         if (!cutoff || cutoff < commit->date)
 694                                 cutoff = commit->date;
 695                 }
 696         }
 697         trace2_region_leave("fetch-pack", "parse_remote_refs_and_find_cutoff", NULL);
 698
 699         /*
 700          * This block marks all local refs as COMPLETE, and then recursively marks all
 701          * parents of those refs as COMPLETE.
 702          */
 703         trace2_region_enter("fetch-pack", "mark_complete_local_refs", NULL);
 704         if (!args->deepen) {
 705                 for_each_ref(mark_complete_oid, NULL);
 706                 for_each_cached_alternate(NULL, mark_alternate_complete);
 707                 commit_list_sort_by_date(&complete);
 708                 if (cutoff)
 709                         mark_recent_complete_commits(args, cutoff);
 710         }
 711         trace2_region_leave("fetch-pack", "mark_complete_local_refs", NULL);
 712
 713         /*
 714          * Mark all complete remote refs as common refs.
 715          * Don't mark them common yet; the server has to be told so first.
 716          */
 717         trace2_region_enter("fetch-pack", "mark_common_remote_refs", NULL);
 718         for (ref = *refs; ref; ref = ref->next) {
 719                 struct object *o = deref_tag(the_repository,
 720                                              lookup_object(the_repository,
 721                                              &ref->old_oid),
 722                                              NULL, 0);
 723
 724                 if (!o || o->type != OBJ_COMMIT || !(o->flags & COMPLETE))
 725                         continue;
 726
 727                 negotiator->known_common(negotiator,
 728                                          (struct commit *)o);
 729         }
 730         trace2_region_leave("fetch-pack", "mark_common_remote_refs", NULL);
 731
 732         save_commit_buffer = old_save_commit_buffer;
 733 }
 734
 735 /*
 736  * Returns 1 if every object pointed to by the given remote refs is available
 737  * locally and reachable from a local ref, and 0 otherwise.
 738  */
 739 static int everything_local(struct fetch_pack_args *args,
 740                             struct ref **refs)
 741 {
 742         struct ref *ref;
 743         int retval;
 744
 745         for (retval = 1, ref = *refs; ref ; ref = ref->next) {
 746                 const struct object_id *remote = &ref->old_oid;
 747                 struct object *o;
 748
 749                 o = lookup_object(the_repository, remote);
 750                 if (!o || !(o->flags & COMPLETE)) {
 751                         retval = 0;
 752                         print_verbose(args, "want %s (%s)", oid_to_hex(remote),
 753                                       ref->name);
 754                         continue;
 755                 }
 756                 print_verbose(args, _("already have %s (%s)"), oid_to_hex(remote),
 757                               ref->name);
 758         }
 759
 760         return retval;
 761 }
 762
 763 static int sideband_demux(int in, int out, void *data)
 764 {
 765         int *xd = data;
 766         int ret;
 767
 768         ret = recv_sideband("fetch-pack", xd[0], out);
 769         close(out);
 770         return ret;
 771 }
 772
 773 static void write_promisor_file(const char *keep_name,
 774                                 struct ref **sought, int nr_sought)
 775 {
 776         struct strbuf promisor_name = STRBUF_INIT;
 777         int suffix_stripped;
 778         FILE *output;
 779         int i;
 780
 781         strbuf_addstr(&promisor_name, keep_name);
 782         suffix_stripped = strbuf_strip_suffix(&promisor_name, ".keep");
 783         if (!suffix_stripped)
 784                 BUG("name of pack lockfile should end with .keep (was '%s')",
 785                     keep_name);
 786         strbuf_addstr(&promisor_name, ".promisor");
 787
 788         output = xfopen(promisor_name.buf, "w");
 789         for (i = 0; i < nr_sought; i++)
 790                 fprintf(output, "%s %s\n", oid_to_hex(&sought[i]->old_oid),
 791                         sought[i]->name);
 792         fclose(output);
 793
 794         strbuf_release(&promisor_name);
 795 }
 796
 797 static int get_pack(struct fetch_pack_args *args,
 798                     int xd[2], struct string_list *pack_lockfiles,
 799                     int only_packfile,
 800                     struct ref **sought, int nr_sought)
 801 {
 802         struct async demux;
 803         int do_keep = args->keep_pack;
 804         const char *cmd_name;
 805         struct pack_header header;
 806         int pass_header = 0;
 807         struct child_process cmd = CHILD_PROCESS_INIT;
 808         int ret;
 809
 810         memset(&demux, 0, sizeof(demux));
 811         if (use_sideband) {
 812                 /* xd[] is talking with upload-pack; subprocess reads from
 813                  * xd[0], spits out band#2 to stderr, and feeds us band#1
 814                  * through demux->out.
 815                  */
 816                 demux.proc = sideband_demux;
 817                 demux.data = xd;
 818                 demux.out = -1;
 819                 demux.isolate_sigpipe = 1;
 820                 if (start_async(&demux))
 821                         die(_("fetch-pack: unable to fork off sideband demultiplexer"));
 822         }
 823         else
 824                 demux.out = xd[0];
 825
 826         if (!args->keep_pack && unpack_limit) {
 827
 828                 if (read_pack_header(demux.out, &header))
 829                         die(_("protocol error: bad pack header"));
 830                 pass_header = 1;
 831                 if (ntohl(header.hdr_entries) < unpack_limit)
 832                         do_keep = 0;
 833                 else
 834                         do_keep = 1;
 835         }
 836
 837         if (alternate_shallow_file) {
 838                 argv_array_push(&cmd.args, "--shallow-file");
 839                 argv_array_push(&cmd.args, alternate_shallow_file);
 840         }
 841
 842         if (do_keep || args->from_promisor) {
 843                 if (pack_lockfiles)
 844                         cmd.out = -1;
 845                 cmd_name = "index-pack";
 846                 argv_array_push(&cmd.args, cmd_name);
 847                 argv_array_push(&cmd.args, "--stdin");
 848                 if (!args->quiet && !args->no_progress)
 849                         argv_array_push(&cmd.args, "-v");
 850                 if (args->use_thin_pack)
 851                         argv_array_push(&cmd.args, "--fix-thin");
 852                 if (do_keep && (args->lock_pack || unpack_limit)) {
 853                         char hostname[HOST_NAME_MAX + 1];
 854                         if (xgethostname(hostname, sizeof(hostname)))
 855                                 xsnprintf(hostname, sizeof(hostname), "localhost");
 856                         argv_array_pushf(&cmd.args,
 857                                         "--keep=fetch-pack %"PRIuMAX " on %s",
 858                                         (uintmax_t)getpid(), hostname);
 859                 }
 860                 if (only_packfile && args->check_self_contained_and_connected)
 861                         argv_array_push(&cmd.args, "--check-self-contained-and-connected");
 862                 else
 863                         /*
 864                          * We cannot perform any connectivity checks because
 865                          * not all packs have been downloaded; let the caller
 866                          * have this responsibility.
 867                          */
 868                         args->check_self_contained_and_connected = 0;
 869                 /*
 870                  * If we're obtaining the filename of a lockfile, we'll use
 871                  * that filename to write a .promisor file with more
 872                  * information below. If not, we need index-pack to do it for
 873                  * us.
 874                  */
 875                 if (!(do_keep && pack_lockfiles) && args->from_promisor)
 876                         argv_array_push(&cmd.args, "--promisor");
 877         }
 878         else {
 879                 cmd_name = "unpack-objects";
 880                 argv_array_push(&cmd.args, cmd_name);
 881                 if (args->quiet || args->no_progress)
 882                         argv_array_push(&cmd.args, "-q");
 883                 args->check_self_contained_and_connected = 0;
 884         }
 885
 886         if (pass_header)
 887                 argv_array_pushf(&cmd.args, "--pack_header=%"PRIu32",%"PRIu32,
 888                                  ntohl(header.hdr_version),
 889                                  ntohl(header.hdr_entries));
 890         if (fetch_fsck_objects >= 0
 891             ? fetch_fsck_objects
 892             : transfer_fsck_objects >= 0
 893             ? transfer_fsck_objects
 894             : 0) {
 895                 if (args->from_promisor)
 896                         /*
 897                          * We cannot use --strict in index-pack because it
 898                          * checks both broken objects and links, but we only
 899                          * want to check for broken objects.
 900                          */
 901                         argv_array_push(&cmd.args, "--fsck-objects");
 902                 else
 903                         argv_array_pushf(&cmd.args, "--strict%s",
 904                                          fsck_msg_types.buf);
 905         }
 906
 907         cmd.in = demux.out;
 908         cmd.git_cmd = 1;
 909         if (start_command(&cmd))
 910                 die(_("fetch-pack: unable to fork off %s"), cmd_name);
 911         if (do_keep && pack_lockfiles) {
 912                 string_list_append_nodup(pack_lockfiles,
 913                                          index_pack_lockfile(cmd.out));
 914                 close(cmd.out);
 915         }
 916
 917         if (!use_sideband)
 918                 /* Closed by start_command() */
 919                 xd[0] = -1;
 920
 921         ret = finish_command(&cmd);
 922         if (!ret || (args->check_self_contained_and_connected && ret == 1))
 923                 args->self_contained_and_connected =
 924                         args->check_self_contained_and_connected &&
 925                         ret == 0;
 926         else
 927                 die(_("%s failed"), cmd_name);
 928         if (use_sideband && finish_async(&demux))
 929                 die(_("error in sideband demultiplexer"));
 930
 931         /*
 932          * Now that index-pack has succeeded, write the promisor file using the
 933          * obtained .keep filename if necessary
 934          */
 935         if (do_keep && pack_lockfiles && pack_lockfiles->nr && args->from_promisor)
 936                 write_promisor_file(pack_lockfiles->items[0].string, sought, nr_sought);
 937
 938         return 0;
 939 }
 940
 941 static int cmp_ref_by_name(const void *a_, const void *b_)
 942 {
 943         const struct ref *a = *((const struct ref **)a_);
 944         const struct ref *b = *((const struct ref **)b_);
 945         return strcmp(a->name, b->name);
 946 }
 947
 948 static struct ref *do_fetch_pack(struct fetch_pack_args *args,
 949                                  int fd[2],
 950                                  const struct ref *orig_ref,
 951                                  struct ref **sought, int nr_sought,
 952                                  struct shallow_info *si,
 953                                  struct string_list *pack_lockfiles)
 954 {
 955         struct repository *r = the_repository;
 956         struct ref *ref = copy_ref_list(orig_ref);
 957         struct object_id oid;
 958         const char *agent_feature;
 959         int agent_len;
 960         struct fetch_negotiator negotiator_alloc;
 961         struct fetch_negotiator *negotiator;
 962
 963         if (args->no_dependents) {
 964                 negotiator = NULL;
 965         } else {
 966                 negotiator = &negotiator_alloc;
 967                 fetch_negotiator_init(r, negotiator);
 968         }
 969
 970         sort_ref_list(&ref, ref_compare_name);
 971         QSORT(sought, nr_sought, cmp_ref_by_name);
 972
 973         if ((agent_feature = server_feature_value("agent", &agent_len))) {
 974                 agent_supported = 1;
 975                 if (agent_len)
 976                         print_verbose(args, _("Server version is %.*s"),
 977                                       agent_len, agent_feature);
 978         }
 979
 980         if (server_supports("shallow"))
 981                 print_verbose(args, _("Server supports %s"), "shallow");
 982         else if (args->depth > 0 || is_repository_shallow(r))
 983                 die(_("Server does not support shallow clients"));
 984         if (args->depth > 0 || args->deepen_since || args->deepen_not)
 985                 args->deepen = 1;
 986         if (server_supports("multi_ack_detailed")) {
 987                 print_verbose(args, _("Server supports %s"), "multi_ack_detailed");
 988                 multi_ack = 2;
 989                 if (server_supports("no-done")) {
 990                         print_verbose(args, _("Server supports %s"), "no-done");
 991                         if (args->stateless_rpc)
 992                                 no_done = 1;
 993                 }
 994         }
 995         else if (server_supports("multi_ack")) {
 996                 print_verbose(args, _("Server supports %s"), "multi_ack");
 997                 multi_ack = 1;
 998         }
 999         if (server_supports("side-band-64k")) {
1000                 print_verbose(args, _("Server supports %s"), "side-band-64k");
1001                 use_sideband = 2;
1002         }
1003         else if (server_supports("side-band")) {
1004                 print_verbose(args, _("Server supports %s"), "side-band");
1005                 use_sideband = 1;
1006         }
1007         if (server_supports("allow-tip-sha1-in-want")) {
1008                 print_verbose(args, _("Server supports %s"), "allow-tip-sha1-in-want");
1009                 allow_unadvertised_object_request |= ALLOW_TIP_SHA1;
1010         }
1011         if (server_supports("allow-reachable-sha1-in-want")) {
1012                 print_verbose(args, _("Server supports %s"), "allow-reachable-sha1-in-want");
1013                 allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
1014         }
1015         if (server_supports("thin-pack"))
1016                 print_verbose(args, _("Server supports %s"), "thin-pack");
1017         else
1018                 args->use_thin_pack = 0;
1019         if (server_supports("no-progress"))
1020                 print_verbose(args, _("Server supports %s"), "no-progress");
1021         else
1022                 args->no_progress = 0;
1023         if (server_supports("include-tag"))
1024                 print_verbose(args, _("Server supports %s"), "include-tag");
1025         else
1026                 args->include_tag = 0;
1027         if (server_supports("ofs-delta"))
1028                 print_verbose(args, _("Server supports %s"), "ofs-delta");
1029         else
1030                 prefer_ofs_delta = 0;
1031
1032         if (server_supports("filter")) {
1033                 server_supports_filtering = 1;
1034                 print_verbose(args, _("Server supports %s"), "filter");
1035         } else if (args->filter_options.choice) {
1036                 warning("filtering not recognized by server, ignoring");
1037         }
1038
1039         if (server_supports("deepen-since")) {
1040                 print_verbose(args, _("Server supports %s"), "deepen-since");
1041                 deepen_since_ok = 1;
1042         } else if (args->deepen_since)
1043                 die(_("Server does not support --shallow-since"));
1044         if (server_supports("deepen-not")) {
1045                 print_verbose(args, _("Server supports %s"), "deepen-not");
1046                 deepen_not_ok = 1;
1047         } else if (args->deepen_not)
1048                 die(_("Server does not support --shallow-exclude"));
1049         if (server_supports("deepen-relative"))
1050                 print_verbose(args, _("Server supports %s"), "deepen-relative");
1051         else if (args->deepen_relative)
1052                 die(_("Server does not support --deepen"));
1053         if (!server_supports_hash(the_hash_algo->name, NULL))
1054                 die(_("Server does not support this repository's object format"));
1055
1056         if (!args->no_dependents) {
1057                 mark_complete_and_common_ref(negotiator, args, &ref);
1058                 filter_refs(args, &ref, sought, nr_sought);
1059                 if (everything_local(args, &ref)) {
1060                         packet_flush(fd[1]);
1061                         goto all_done;
1062                 }
1063         } else {
1064                 filter_refs(args, &ref, sought, nr_sought);
1065         }
1066         if (find_common(negotiator, args, fd, &oid, ref) < 0)
1067                 if (!args->keep_pack)
1068                         /* When cloning, it is not unusual to have
1069                          * no common commit.
1070                          */
1071                         warning(_("no common commits"));
1072
1073         if (args->stateless_rpc)
1074                 packet_flush(fd[1]);
1075         if (args->deepen)
1076                 setup_alternate_shallow(&shallow_lock, &alternate_shallow_file,
1077                                         NULL);
1078         else if (si->nr_ours || si->nr_theirs)
1079                 alternate_shallow_file = setup_temporary_shallow(si->shallow);
1080         else
1081                 alternate_shallow_file = NULL;
1082         if (get_pack(args, fd, pack_lockfiles, 1, sought, nr_sought))
1083                 die(_("git fetch-pack: fetch failed."));
1084
1085  all_done:
1086         if (negotiator)
1087                 negotiator->release(negotiator);
1088         return ref;
1089 }
1090
1091 static void add_shallow_requests(struct strbuf *req_buf,
1092                                  const struct fetch_pack_args *args)
1093 {
1094         if (is_repository_shallow(the_repository))
1095                 write_shallow_commits(req_buf, 1, NULL);
1096         if (args->depth > 0)
1097                 packet_buf_write(req_buf, "deepen %d", args->depth);
1098         if (args->deepen_since) {
1099                 timestamp_t max_age = approxidate(args->deepen_since);
1100                 packet_buf_write(req_buf, "deepen-since %"PRItime, max_age);
1101         }
1102         if (args->deepen_not) {
1103                 int i;
1104                 for (i = 0; i < args->deepen_not->nr; i++) {
1105                         struct string_list_item *s = args->deepen_not->items + i;
1106                         packet_buf_write(req_buf, "deepen-not %s", s->string);
1107                 }
1108         }
1109         if (args->deepen_relative)
1110                 packet_buf_write(req_buf, "deepen-relative\n");
1111 }
1112
1113 static void add_wants(int no_dependents, const struct ref *wants, struct strbuf *req_buf)
1114 {
1115         int use_ref_in_want = server_supports_feature("fetch", "ref-in-want", 0);
1116
1117         for ( ; wants ; wants = wants->next) {
1118                 const struct object_id *remote = &wants->old_oid;
1119                 struct object *o;
1120
1121                 /*
1122                  * If that object is complete (i.e. it is an ancestor of a
1123                  * local ref), we tell them we have it but do not have to
1124                  * tell them about its ancestors, which they already know
1125                  * about.
1126                  *
1127                  * We use lookup_object here because we are only
1128                  * interested in the case we *know* the object is
1129                  * reachable and we have already scanned it.
1130                  *
1131                  * Do this only if args->no_dependents is false (if it is true,
1132                  * we cannot trust the object flags).
1133                  */
1134                 if (!no_dependents &&
1135                     ((o = lookup_object(the_repository, remote)) != NULL) &&
1136                     (o->flags & COMPLETE)) {
1137                         continue;
1138                 }
1139
1140                 if (!use_ref_in_want || wants->exact_oid)
1141                         packet_buf_write(req_buf, "want %s\n", oid_to_hex(remote));
1142                 else
1143                         packet_buf_write(req_buf, "want-ref %s\n", wants->name);
1144         }
1145 }
1146
1147 static void add_common(struct strbuf *req_buf, struct oidset *common)
1148 {
1149         struct oidset_iter iter;
1150         const struct object_id *oid;
1151         oidset_iter_init(common, &iter);
1152
1153         while ((oid = oidset_iter_next(&iter))) {
1154                 packet_buf_write(req_buf, "have %s\n", oid_to_hex(oid));
1155         }
1156 }
1157
1158 static int add_haves(struct fetch_negotiator *negotiator,
1159                      int seen_ack,
1160                      struct strbuf *req_buf,
1161                      int *haves_to_send, int *in_vain)
1162 {
1163         int ret = 0;
1164         int haves_added = 0;
1165         const struct object_id *oid;
1166
1167         while ((oid = negotiator->next(negotiator))) {
1168                 packet_buf_write(req_buf, "have %s\n", oid_to_hex(oid));
1169                 if (++haves_added >= *haves_to_send)
1170                         break;
1171         }
1172
1173         *in_vain += haves_added;
1174         if (!haves_added || (seen_ack && *in_vain >= MAX_IN_VAIN)) {
1175                 /* Send Done */
1176                 packet_buf_write(req_buf, "done\n");
1177                 ret = 1;
1178         }
1179
1180         /* Increase haves to send on next round */
1181         *haves_to_send = next_flush(1, *haves_to_send);
1182
1183         return ret;
1184 }
1185
1186 static int send_fetch_request(struct fetch_negotiator *negotiator, int fd_out,
1187                               struct fetch_pack_args *args,
1188                               const struct ref *wants, struct oidset *common,
1189                               int *haves_to_send, int *in_vain,
1190                               int sideband_all, int seen_ack)
1191 {
1192         int ret = 0;
1193         const char *hash_name;
1194         struct strbuf req_buf = STRBUF_INIT;
1195
1196         if (server_supports_v2("fetch", 1))
1197                 packet_buf_write(&req_buf, "command=fetch");
1198         if (server_supports_v2("agent", 0))
1199                 packet_buf_write(&req_buf, "agent=%s", git_user_agent_sanitized());
1200         if (args->server_options && args->server_options->nr &&
1201             server_supports_v2("server-option", 1)) {
1202                 int i;
1203                 for (i = 0; i < args->server_options->nr; i++)
1204                         packet_buf_write(&req_buf, "server-option=%s",
1205                                          args->server_options->items[i].string);
1206         }
1207
1208         if (server_feature_v2("object-format", &hash_name)) {
1209                 int hash_algo = hash_algo_by_name(hash_name);
1210                 if (hash_algo_by_ptr(the_hash_algo) != hash_algo)
1211                         die(_("mismatched algorithms: client %s; server %s"),
1212                             the_hash_algo->name, hash_name);
1213                 packet_write_fmt(fd_out, "object-format=%s", the_hash_algo->name);
1214         } else if (hash_algo_by_ptr(the_hash_algo) != GIT_HASH_SHA1) {
1215                 die(_("the server does not support algorithm '%s'"),
1216                     the_hash_algo->name);
1217         }
1218
1219         packet_buf_delim(&req_buf);
1220         if (args->use_thin_pack)
1221                 packet_buf_write(&req_buf, "thin-pack");
1222         if (args->no_progress)
1223                 packet_buf_write(&req_buf, "no-progress");
1224         if (args->include_tag)
1225                 packet_buf_write(&req_buf, "include-tag");
1226         if (prefer_ofs_delta)
1227                 packet_buf_write(&req_buf, "ofs-delta");
1228         if (sideband_all)
1229                 packet_buf_write(&req_buf, "sideband-all");
1230
1231         /* Add shallow-info and deepen request */
1232         if (server_supports_feature("fetch", "shallow", 0))
1233                 add_shallow_requests(&req_buf, args);
1234         else if (is_repository_shallow(the_repository) || args->deepen)
1235                 die(_("Server does not support shallow requests"));
1236
1237         /* Add filter */
1238         if (server_supports_feature("fetch", "filter", 0) &&
1239             args->filter_options.choice) {
1240                 const char *spec =
1241                         expand_list_objects_filter_spec(&args->filter_options);
1242                 print_verbose(args, _("Server supports filter"));
1243                 packet_buf_write(&req_buf, "filter %s", spec);
1244         } else if (args->filter_options.choice) {
1245                 warning("filtering not recognized by server, ignoring");
1246         }
1247
1248         if (server_supports_feature("fetch", "packfile-uris", 0)) {
1249                 int i;
1250                 struct strbuf to_send = STRBUF_INIT;
1251
1252                 for (i = 0; i < uri_protocols.nr; i++) {
1253                         const char *s = uri_protocols.items[i].string;
1254
1255                         if (!strcmp(s, "https") || !strcmp(s, "http")) {
1256                                 if (to_send.len)
1257                                         strbuf_addch(&to_send, ',');
1258                                 strbuf_addstr(&to_send, s);
1259                         }
1260                 }
1261                 if (to_send.len) {
1262                         packet_buf_write(&req_buf, "packfile-uris %s",
1263                                          to_send.buf);
1264                         strbuf_release(&to_send);
1265                 }
1266         }
1267
1268         /* add wants */
1269         add_wants(args->no_dependents, wants, &req_buf);
1270
1271         if (args->no_dependents) {
1272                 packet_buf_write(&req_buf, "done");
1273                 ret = 1;
1274         } else {
1275                 /* Add all of the common commits we've found in previous rounds */
1276                 add_common(&req_buf, common);
1277
1278                 /* Add initial haves */
1279                 ret = add_haves(negotiator, seen_ack, &req_buf,
1280                                 haves_to_send, in_vain);
1281         }
1282
1283         /* Send request */
1284         packet_buf_flush(&req_buf);
1285         if (write_in_full(fd_out, req_buf.buf, req_buf.len) < 0)
1286                 die_errno(_("unable to write request to remote"));
1287
1288         strbuf_release(&req_buf);
1289         return ret;
1290 }
1291
1292 /*
1293  * Processes a section header in a server's response and checks if it matches
1294  * `section`.  If the value of `peek` is 1, the header line will be peeked (and
1295  * not consumed); if 0, the line will be consumed and the function will die if
1296  * the section header doesn't match what was expected.
1297  */
1298 static int process_section_header(struct packet_reader *reader,
1299                                   const char *section, int peek)
1300 {
1301         int ret;
1302
1303         if (packet_reader_peek(reader) != PACKET_READ_NORMAL)
1304                 die(_("error reading section header '%s'"), section);
1305
1306         ret = !strcmp(reader->line, section);
1307
1308         if (!peek) {
1309                 if (!ret)
1310                         die(_("expected '%s', received '%s'"),
1311                             section, reader->line);
1312                 packet_reader_read(reader);
1313         }
1314
1315         return ret;
1316 }
1317
1318 enum common_found {
1319         /*
1320          * No commit was found to be possessed by both the client and the
1321          * server, and "ready" was not received.
1322          */
1323         NO_COMMON_FOUND,
1324
1325         /*
1326          * At least one commit was found to be possessed by both the client and
1327          * the server, and "ready" was not received.
1328          */
1329         COMMON_FOUND,
1330
1331         /*
1332          * "ready" was received, indicating that the server is ready to send
1333          * the packfile without any further negotiation.
1334          */
1335         READY
1336 };
1337
1338 static enum common_found process_acks(struct fetch_negotiator *negotiator,
1339                                       struct packet_reader *reader,
1340                                       struct oidset *common)
1341 {
1342         /* received */
1343         int received_ready = 0;
1344         int received_ack = 0;
1345
1346         process_section_header(reader, "acknowledgments", 0);
1347         while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
1348                 const char *arg;
1349
1350                 if (!strcmp(reader->line, "NAK"))
1351                         continue;
1352
1353                 if (skip_prefix(reader->line, "ACK ", &arg)) {
1354                         struct object_id oid;
1355                         received_ack = 1;
1356                         if (!get_oid_hex(arg, &oid)) {
1357                                 struct commit *commit;
1358                                 oidset_insert(common, &oid);
1359                                 commit = lookup_commit(the_repository, &oid);
1360                                 if (negotiator)
1361                                         negotiator->ack(negotiator, commit);
1362                         }
1363                         continue;
1364                 }
1365
1366                 if (!strcmp(reader->line, "ready")) {
1367                         received_ready = 1;
1368                         continue;
1369                 }
1370
1371                 die(_("unexpected acknowledgment line: '%s'"), reader->line);
1372         }
1373
1374         if (reader->status != PACKET_READ_FLUSH &&
1375             reader->status != PACKET_READ_DELIM)
1376                 die(_("error processing acks: %d"), reader->status);
1377
1378         /*
1379          * If an "acknowledgments" section is sent, a packfile is sent if and
1380          * only if "ready" was sent in this section. The other sections
1381          * ("shallow-info" and "wanted-refs") are sent only if a packfile is
1382          * sent. Therefore, a DELIM is expected if "ready" is sent, and a FLUSH
1383          * otherwise.
1384          */
1385         if (received_ready && reader->status != PACKET_READ_DELIM)
1386                 die(_("expected packfile to be sent after 'ready'"));
1387         if (!received_ready && reader->status != PACKET_READ_FLUSH)
1388                 die(_("expected no other sections to be sent after no 'ready'"));
1389
1390         return received_ready ? READY :
1391                 (received_ack ? COMMON_FOUND : NO_COMMON_FOUND);
1392 }
1393
1394 static void receive_shallow_info(struct fetch_pack_args *args,
1395                                  struct packet_reader *reader,
1396                                  struct oid_array *shallows,
1397                                  struct shallow_info *si)
1398 {
1399         int unshallow_received = 0;
1400
1401         process_section_header(reader, "shallow-info", 0);
1402         while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
1403                 const char *arg;
1404                 struct object_id oid;
1405
1406                 if (skip_prefix(reader->line, "shallow ", &arg)) {
1407                         if (get_oid_hex(arg, &oid))
1408                                 die(_("invalid shallow line: %s"), reader->line);
1409                         oid_array_append(shallows, &oid);
1410                         continue;
1411                 }
1412                 if (skip_prefix(reader->line, "unshallow ", &arg)) {
1413                         if (get_oid_hex(arg, &oid))
1414                                 die(_("invalid unshallow line: %s"), reader->line);
1415                         if (!lookup_object(the_repository, &oid))
1416                                 die(_("object not found: %s"), reader->line);
1417                         /* make sure that it is parsed as shallow */
1418                         if (!parse_object(the_repository, &oid))
1419                                 die(_("error in object: %s"), reader->line);
1420                         if (unregister_shallow(&oid))
1421                                 die(_("no shallow found: %s"), reader->line);
1422                         unshallow_received = 1;
1423                         continue;
1424                 }
1425                 die(_("expected shallow/unshallow, got %s"), reader->line);
1426         }
1427
1428         if (reader->status != PACKET_READ_FLUSH &&
1429             reader->status != PACKET_READ_DELIM)
1430                 die(_("error processing shallow info: %d"), reader->status);
1431
1432         if (args->deepen || unshallow_received) {
1433                 /*
1434                  * Treat these as shallow lines caused by our depth settings.
1435                  * In v0, these lines cannot cause refs to be rejected; do the
1436                  * same.
1437                  */
1438                 int i;
1439
1440                 for (i = 0; i < shallows->nr; i++)
1441                         register_shallow(the_repository, &shallows->oid[i]);
1442                 setup_alternate_shallow(&shallow_lock, &alternate_shallow_file,
1443                                         NULL);
1444                 args->deepen = 1;
1445         } else if (shallows->nr) {
1446                 /*
1447                  * Treat these as shallow lines caused by the remote being
1448                  * shallow. In v0, remote refs that reach these objects are
1449                  * rejected (unless --update-shallow is set); do the same.
1450                  */
1451                 prepare_shallow_info(si, shallows);
1452                 if (si->nr_ours || si->nr_theirs)
1453                         alternate_shallow_file =
1454                                 setup_temporary_shallow(si->shallow);
1455                 else
1456                         alternate_shallow_file = NULL;
1457         } else {
1458                 alternate_shallow_file = NULL;
1459         }
1460 }
1461
1462 static int cmp_name_ref(const void *name, const void *ref)
1463 {
1464         return strcmp(name, (*(struct ref **)ref)->name);
1465 }
1466
1467 static void receive_wanted_refs(struct packet_reader *reader,
1468                                 struct ref **sought, int nr_sought)
1469 {
1470         process_section_header(reader, "wanted-refs", 0);
1471         while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
1472                 struct object_id oid;
1473                 const char *end;
1474                 struct ref **found;
1475
1476                 if (parse_oid_hex(reader->line, &oid, &end) || *end++ != ' ')
1477                         die(_("expected wanted-ref, got '%s'"), reader->line);
1478
1479                 found = bsearch(end, sought, nr_sought, sizeof(*sought),
1480                                 cmp_name_ref);
1481                 if (!found)
1482                         die(_("unexpected wanted-ref: '%s'"), reader->line);
1483                 oidcpy(&(*found)->old_oid, &oid);
1484         }
1485
1486         if (reader->status != PACKET_READ_DELIM)
1487                 die(_("error processing wanted refs: %d"), reader->status);
1488 }
1489
1490 static void receive_packfile_uris(struct packet_reader *reader,
1491                                   struct string_list *uris)
1492 {
1493         process_section_header(reader, "packfile-uris", 0);
1494         while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
1495                 if (reader->pktlen < the_hash_algo->hexsz ||
1496                     reader->line[the_hash_algo->hexsz] != ' ')
1497                         die("expected '<hash> <uri>', got: %s\n", reader->line);
1498
1499                 string_list_append(uris, reader->line);
1500         }
1501         if (reader->status != PACKET_READ_DELIM)
1502                 die("expected DELIM");
1503 }
1504
1505 enum fetch_state {
1506         FETCH_CHECK_LOCAL = 0,
1507         FETCH_SEND_REQUEST,
1508         FETCH_PROCESS_ACKS,
1509         FETCH_GET_PACK,
1510         FETCH_DONE,
1511 };
1512
1513 static void do_check_stateless_delimiter(const struct fetch_pack_args *args,
1514                                          struct packet_reader *reader)
1515 {
1516         check_stateless_delimiter(args->stateless_rpc, reader,
1517                                   _("git fetch-pack: expected response end packet"));
1518 }
1519
1520 static struct ref *do_fetch_pack_v2(struct fetch_pack_args *args,
1521                                     int fd[2],
1522                                     const struct ref *orig_ref,
1523                                     struct ref **sought, int nr_sought,
1524                                     struct oid_array *shallows,
1525                                     struct shallow_info *si,
1526                                     struct string_list *pack_lockfiles)
1527 {
1528         struct repository *r = the_repository;
1529         struct ref *ref = copy_ref_list(orig_ref);
1530         enum fetch_state state = FETCH_CHECK_LOCAL;
1531         struct oidset common = OIDSET_INIT;
1532         struct packet_reader reader;
1533         int in_vain = 0, negotiation_started = 0;
1534         int haves_to_send = INITIAL_FLUSH;
1535         struct fetch_negotiator negotiator_alloc;
1536         struct fetch_negotiator *negotiator;
1537         int seen_ack = 0;
1538         struct string_list packfile_uris = STRING_LIST_INIT_DUP;
1539         int i;
1540
1541         if (args->no_dependents) {
1542                 negotiator = NULL;
1543         } else {
1544                 negotiator = &negotiator_alloc;
1545                 fetch_negotiator_init(r, negotiator);
1546         }
1547
1548         packet_reader_init(&reader, fd[0], NULL, 0,
1549                            PACKET_READ_CHOMP_NEWLINE |
1550                            PACKET_READ_DIE_ON_ERR_PACKET);
1551         if (git_env_bool("GIT_TEST_SIDEBAND_ALL", 1) &&
1552             server_supports_feature("fetch", "sideband-all", 0)) {
1553                 reader.use_sideband = 1;
1554                 reader.me = "fetch-pack";
1555         }
1556
1557         while (state != FETCH_DONE) {
1558                 switch (state) {
1559                 case FETCH_CHECK_LOCAL:
1560                         sort_ref_list(&ref, ref_compare_name);
1561                         QSORT(sought, nr_sought, cmp_ref_by_name);
1562
1563                         /* v2 supports these by default */
1564                         allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
1565                         use_sideband = 2;
1566                         if (args->depth > 0 || args->deepen_since || args->deepen_not)
1567                                 args->deepen = 1;
1568
1569                         /* Filter 'ref' by 'sought' and those that aren't local */
1570                         if (!args->no_dependents) {
1571                                 mark_complete_and_common_ref(negotiator, args, &ref);
1572                                 filter_refs(args, &ref, sought, nr_sought);
1573                                 if (everything_local(args, &ref))
1574                                         state = FETCH_DONE;
1575                                 else
1576                                         state = FETCH_SEND_REQUEST;
1577
1578                                 mark_tips(negotiator, args->negotiation_tips);
1579                                 for_each_cached_alternate(negotiator,
1580                                                           insert_one_alternate_object);
1581                         } else {
1582                                 filter_refs(args, &ref, sought, nr_sought);
1583                                 state = FETCH_SEND_REQUEST;
1584                         }
1585                         break;
1586                 case FETCH_SEND_REQUEST:
1587                         if (!negotiation_started) {
1588                                 negotiation_started = 1;
1589                                 trace2_region_enter("fetch-pack",
1590                                                     "negotiation_v2",
1591                                                     the_repository);
1592                         }
1593                         if (send_fetch_request(negotiator, fd[1], args, ref,
1594                                                &common,
1595                                                &haves_to_send, &in_vain,
1596                                                reader.use_sideband,
1597                                                seen_ack))
1598                                 state = FETCH_GET_PACK;
1599                         else
1600                                 state = FETCH_PROCESS_ACKS;
1601                         break;
1602                 case FETCH_PROCESS_ACKS:
1603                         /* Process ACKs/NAKs */
1604                         switch (process_acks(negotiator, &reader, &common)) {
1605                         case READY:
1606                                 /*
1607                                  * Don't check for response delimiter; get_pack() will
1608                                  * read the rest of this response.
1609                                  */
1610                                 state = FETCH_GET_PACK;
1611                                 break;
1612                         case COMMON_FOUND:
1613                                 in_vain = 0;
1614                                 seen_ack = 1;
1615                                 /* fallthrough */
1616                         case NO_COMMON_FOUND:
1617                                 do_check_stateless_delimiter(args, &reader);
1618                                 state = FETCH_SEND_REQUEST;
1619                                 break;
1620                         }
1621                         break;
1622                 case FETCH_GET_PACK:
1623                         trace2_region_leave("fetch-pack",
1624                                             "negotiation_v2",
1625                                             the_repository);
1626                         /* Check for shallow-info section */
1627                         if (process_section_header(&reader, "shallow-info", 1))
1628                                 receive_shallow_info(args, &reader, shallows, si);
1629
1630                         if (process_section_header(&reader, "wanted-refs", 1))
1631                                 receive_wanted_refs(&reader, sought, nr_sought);
1632
1633                         /* get the pack(s) */
1634                         if (process_section_header(&reader, "packfile-uris", 1))
1635                                 receive_packfile_uris(&reader, &packfile_uris);
1636                         process_section_header(&reader, "packfile", 0);
1637                         if (get_pack(args, fd, pack_lockfiles,
1638                                      !packfile_uris.nr, sought, nr_sought))
1639                                 die(_("git fetch-pack: fetch failed."));
1640                         do_check_stateless_delimiter(args, &reader);
1641
1642                         state = FETCH_DONE;
1643                         break;
1644                 case FETCH_DONE:
1645                         continue;
1646                 }
1647         }
1648
1649         for (i = 0; i < packfile_uris.nr; i++) {
1650                 struct child_process cmd = CHILD_PROCESS_INIT;
1651                 char packname[GIT_MAX_HEXSZ + 1];
1652                 const char *uri = packfile_uris.items[i].string +
1653                         the_hash_algo->hexsz + 1;
1654
1655                 argv_array_push(&cmd.args, "http-fetch");
1656                 argv_array_pushf(&cmd.args, "--packfile=%.*s",
1657                                  (int) the_hash_algo->hexsz,
1658                                  packfile_uris.items[i].string);
1659                 argv_array_push(&cmd.args, uri);
1660                 cmd.git_cmd = 1;
1661                 cmd.no_stdin = 1;
1662                 cmd.out = -1;
1663                 if (start_command(&cmd))
1664                         die("fetch-pack: unable to spawn http-fetch");
1665
1666                 if (read_in_full(cmd.out, packname, 5) < 0 ||
1667                     memcmp(packname, "keep\t", 5))
1668                         die("fetch-pack: expected keep then TAB at start of http-fetch output");
1669
1670                 if (read_in_full(cmd.out, packname,
1671                                  the_hash_algo->hexsz + 1) < 0 ||
1672                     packname[the_hash_algo->hexsz] != '\n')
1673                         die("fetch-pack: expected hash then LF at end of http-fetch output");
1674
1675                 packname[the_hash_algo->hexsz] = '\0';
1676
1677                 close(cmd.out);
1678
1679                 if (finish_command(&cmd))
1680                         die("fetch-pack: unable to finish http-fetch");
1681
1682                 if (memcmp(packfile_uris.items[i].string, packname,
1683                            the_hash_algo->hexsz))
1684                         die("fetch-pack: pack downloaded from %s does not match expected hash %.*s",
1685                             uri, (int) the_hash_algo->hexsz,
1686                             packfile_uris.items[i].string);
1687
1688                 string_list_append_nodup(pack_lockfiles,
1689                                          xstrfmt("%s/pack/pack-%s.keep",
1690                                                  get_object_directory(),
1691                                                  packname));
1692         }
1693         string_list_clear(&packfile_uris, 0);
1694
1695         if (negotiator)
1696                 negotiator->release(negotiator);
1697
1698         oidset_clear(&common);
1699         return ref;
1700 }
1701
1702 static int fetch_pack_config_cb(const char *var, const char *value, void *cb)
1703 {
1704         if (strcmp(var, "fetch.fsck.skiplist") == 0) {
1705                 const char *path;
1706
1707                 if (git_config_pathname(&path, var, value))
1708                         return 1;
1709                 strbuf_addf(&fsck_msg_types, "%cskiplist=%s",
1710                         fsck_msg_types.len ? ',' : '=', path);
1711                 free((char *)path);
1712                 return 0;
1713         }
1714
1715         if (skip_prefix(var, "fetch.fsck.", &var)) {
1716                 if (is_valid_msg_type(var, value))
1717                         strbuf_addf(&fsck_msg_types, "%c%s=%s",
1718                                 fsck_msg_types.len ? ',' : '=', var, value);
1719                 else
1720                         warning("Skipping unknown msg id '%s'", var);
1721                 return 0;
1722         }
1723
1724         return git_default_config(var, value, cb);
1725 }
1726
1727 static void fetch_pack_config(void)
1728 {
1729         git_config_get_int("fetch.unpacklimit", &fetch_unpack_limit);
1730         git_config_get_int("transfer.unpacklimit", &transfer_unpack_limit);
1731         git_config_get_bool("repack.usedeltabaseoffset", &prefer_ofs_delta);
1732         git_config_get_bool("fetch.fsckobjects", &fetch_fsck_objects);
1733         git_config_get_bool("transfer.fsckobjects", &transfer_fsck_objects);
1734         if (!uri_protocols.nr) {
1735                 char *str;
1736
1737                 if (!git_config_get_string("fetch.uriprotocols", &str) && str) {
1738                         string_list_split(&uri_protocols, str, ',', -1);
1739                         free(str);
1740                 }
1741         }
1742
1743         git_config(fetch_pack_config_cb, NULL);
1744 }
1745
1746 static void fetch_pack_setup(void)
1747 {
1748         static int did_setup;
1749         if (did_setup)
1750                 return;
1751         fetch_pack_config();
1752         if (0 <= transfer_unpack_limit)
1753                 unpack_limit = transfer_unpack_limit;
1754         else if (0 <= fetch_unpack_limit)
1755                 unpack_limit = fetch_unpack_limit;
1756         did_setup = 1;
1757 }
1758
1759 static int remove_duplicates_in_refs(struct ref **ref, int nr)
1760 {
1761         struct string_list names = STRING_LIST_INIT_NODUP;
1762         int src, dst;
1763
1764         for (src = dst = 0; src < nr; src++) {
1765                 struct string_list_item *item;
1766                 item = string_list_insert(&names, ref[src]->name);
1767                 if (item->util)
1768                         continue; /* already have it */
1769                 item->util = ref[src];
1770                 if (src != dst)
1771                         ref[dst] = ref[src];
1772                 dst++;
1773         }
1774         for (src = dst; src < nr; src++)
1775                 ref[src] = NULL;
1776         string_list_clear(&names, 0);
1777         return dst;
1778 }
1779
1780 static void update_shallow(struct fetch_pack_args *args,
1781                            struct ref **sought, int nr_sought,
1782                            struct shallow_info *si)
1783 {
1784         struct oid_array ref = OID_ARRAY_INIT;
1785         int *status;
1786         int i;
1787
1788         if (args->deepen && alternate_shallow_file) {
1789                 if (*alternate_shallow_file == '\0') { /* --unshallow */
1790                         unlink_or_warn(git_path_shallow(the_repository));
1791                         rollback_shallow_file(the_repository, &shallow_lock);
1792                 } else
1793                         commit_shallow_file(the_repository, &shallow_lock);
1794                 alternate_shallow_file = NULL;
1795                 return;
1796         }
1797
1798         if (!si->shallow || !si->shallow->nr)
1799                 return;
1800
1801         if (args->cloning) {
1802                 /*
1803                  * remote is shallow, but this is a clone, there are
1804                  * no objects in repo to worry about. Accept any
1805                  * shallow points that exist in the pack (iow in repo
1806                  * after get_pack() and reprepare_packed_git())
1807                  */
1808                 struct oid_array extra = OID_ARRAY_INIT;
1809                 struct object_id *oid = si->shallow->oid;
1810                 for (i = 0; i < si->shallow->nr; i++)
1811                         if (has_object_file(&oid[i]))
1812                                 oid_array_append(&extra, &oid[i]);
1813                 if (extra.nr) {
1814                         setup_alternate_shallow(&shallow_lock,
1815                                                 &alternate_shallow_file,
1816                                                 &extra);
1817                         commit_shallow_file(the_repository, &shallow_lock);
1818                         alternate_shallow_file = NULL;
1819                 }
1820                 oid_array_clear(&extra);
1821                 return;
1822         }
1823
1824         if (!si->nr_ours && !si->nr_theirs)
1825                 return;
1826
1827         remove_nonexistent_theirs_shallow(si);
1828         if (!si->nr_ours && !si->nr_theirs)
1829                 return;
1830         for (i = 0; i < nr_sought; i++)
1831                 oid_array_append(&ref, &sought[i]->old_oid);
1832         si->ref = &ref;
1833
1834         if (args->update_shallow) {
1835                 /*
1836                  * remote is also shallow, .git/shallow may be updated
1837                  * so all refs can be accepted. Make sure we only add
1838                  * shallow roots that are actually reachable from new
1839                  * refs.
1840                  */
1841                 struct oid_array extra = OID_ARRAY_INIT;
1842                 struct object_id *oid = si->shallow->oid;
1843                 assign_shallow_commits_to_refs(si, NULL, NULL);
1844                 if (!si->nr_ours && !si->nr_theirs) {
1845                         oid_array_clear(&ref);
1846                         return;
1847                 }
1848                 for (i = 0; i < si->nr_ours; i++)
1849                         oid_array_append(&extra, &oid[si->ours[i]]);
1850                 for (i = 0; i < si->nr_theirs; i++)
1851                         oid_array_append(&extra, &oid[si->theirs[i]]);
1852                 setup_alternate_shallow(&shallow_lock,
1853                                         &alternate_shallow_file,
1854                                         &extra);
1855                 commit_shallow_file(the_repository, &shallow_lock);
1856                 oid_array_clear(&extra);
1857                 oid_array_clear(&ref);
1858                 alternate_shallow_file = NULL;
1859                 return;
1860         }
1861
1862         /*
1863          * remote is also shallow, check what ref is safe to update
1864          * without updating .git/shallow
1865          */
1866         status = xcalloc(nr_sought, sizeof(*status));
1867         assign_shallow_commits_to_refs(si, NULL, status);
1868         if (si->nr_ours || si->nr_theirs) {
1869                 for (i = 0; i < nr_sought; i++)
1870                         if (status[i])
1871                                 sought[i]->status = REF_STATUS_REJECT_SHALLOW;
1872         }
1873         free(status);
1874         oid_array_clear(&ref);
1875 }
1876
1877 static int iterate_ref_map(void *cb_data, struct object_id *oid)
1878 {
1879         struct ref **rm = cb_data;
1880         struct ref *ref = *rm;
1881
1882         if (!ref)
1883                 return -1; /* end of the list */
1884         *rm = ref->next;
1885         oidcpy(oid, &ref->old_oid);
1886         return 0;
1887 }
1888
1889 struct ref *fetch_pack(struct fetch_pack_args *args,
1890                        int fd[],
1891                        const struct ref *ref,
1892                        struct ref **sought, int nr_sought,
1893                        struct oid_array *shallow,
1894                        struct string_list *pack_lockfiles,
1895                        enum protocol_version version)
1896 {
1897         struct ref *ref_cpy;
1898         struct shallow_info si;
1899         struct oid_array shallows_scratch = OID_ARRAY_INIT;
1900
1901         fetch_pack_setup();
1902         if (nr_sought)
1903                 nr_sought = remove_duplicates_in_refs(sought, nr_sought);
1904
1905         if (args->no_dependents && !args->filter_options.choice) {
1906                 /*
1907                  * The protocol does not support requesting that only the
1908                  * wanted objects be sent, so approximate this by setting a
1909                  * "blob:none" filter if no filter is already set. This works
1910                  * for all object types: note that wanted blobs will still be
1911                  * sent because they are directly specified as a "want".
1912                  *
1913                  * NEEDSWORK: Add an option in the protocol to request that
1914                  * only the wanted objects be sent, and implement it.
1915                  */
1916                 parse_list_objects_filter(&args->filter_options, "blob:none");
1917         }
1918
1919         if (version != protocol_v2 && !ref) {
1920                 packet_flush(fd[1]);
1921                 die(_("no matching remote head"));
1922         }
1923         if (version == protocol_v2) {
1924                 if (shallow->nr)
1925                         BUG("Protocol V2 does not provide shallows at this point in the fetch");
1926                 memset(&si, 0, sizeof(si));
1927                 ref_cpy = do_fetch_pack_v2(args, fd, ref, sought, nr_sought,
1928                                            &shallows_scratch, &si,
1929                                            pack_lockfiles);
1930         } else {
1931                 prepare_shallow_info(&si, shallow);
1932                 ref_cpy = do_fetch_pack(args, fd, ref, sought, nr_sought,
1933                                         &si, pack_lockfiles);
1934         }
1935         reprepare_packed_git(the_repository);
1936
1937         if (!args->cloning && args->deepen) {
1938                 struct check_connected_options opt = CHECK_CONNECTED_INIT;
1939                 struct ref *iterator = ref_cpy;
1940                 opt.shallow_file = alternate_shallow_file;
1941                 if (args->deepen)
1942                         opt.is_deepening_fetch = 1;
1943                 if (check_connected(iterate_ref_map, &iterator, &opt)) {
1944                         error(_("remote did not send all necessary objects"));
1945                         free_refs(ref_cpy);
1946                         ref_cpy = NULL;
1947                         rollback_shallow_file(the_repository, &shallow_lock);
1948                         goto cleanup;
1949                 }
1950                 args->connectivity_checked = 1;
1951         }
1952
1953         update_shallow(args, sought, nr_sought, &si);
1954 cleanup:
1955         clear_shallow_info(&si);
1956         oid_array_clear(&shallows_scratch);
1957         return ref_cpy;
1958 }
1959
1960 int report_unmatched_refs(struct ref **sought, int nr_sought)
1961 {
1962         int i, ret = 0;
1963
1964         for (i = 0; i < nr_sought; i++) {
1965                 if (!sought[i])
1966                         continue;
1967                 switch (sought[i]->match_status) {
1968                 case REF_MATCHED:
1969                         continue;
1970                 case REF_NOT_MATCHED:
1971                         error(_("no such remote ref %s"), sought[i]->name);
1972                         break;
1973                 case REF_UNADVERTISED_NOT_ALLOWED:
1974                         error(_("Server does not allow request for unadvertised object %s"),
1975                               sought[i]->name);
1976                         break;
1977                 }
1978                 ret = 1;
1979         }
1980         return ret;
1981 }