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

   1 #include "cache.h"
   2 #include "config.h"
   3 #include "lockfile.h"
   4 #include "refs.h"
   5 #include "pkt-line.h"
   6 #include "commit.h"
   7 #include "tag.h"
   8 #include "exec_cmd.h"
   9 #include "pack.h"
  10 #include "sideband.h"
  11 #include "fetch-pack.h"
  12 #include "remote.h"
  13 #include "run-command.h"
  14 #include "connect.h"
  15 #include "transport.h"
  16 #include "version.h"
  17 #include "prio-queue.h"
  18 #include "sha1-array.h"
  19 #include "oidset.h"
  20 #include "packfile.h"
  21
  22 static int transfer_unpack_limit = -1;
  23 static int fetch_unpack_limit = -1;
  24 static int unpack_limit = 100;
  25 static int prefer_ofs_delta = 1;
  26 static int no_done;
  27 static int deepen_since_ok;
  28 static int deepen_not_ok;
  29 static int fetch_fsck_objects = -1;
  30 static int transfer_fsck_objects = -1;
  31 static int agent_supported;
  32 static int server_supports_filtering;
  33 static struct lock_file shallow_lock;
  34 static const char *alternate_shallow_file;
  35
  36 /* Remember to update object flag allocation in object.h */
  37 #define COMPLETE        (1U << 0)
  38 #define COMMON          (1U << 1)
  39 #define COMMON_REF      (1U << 2)
  40 #define SEEN            (1U << 3)
  41 #define POPPED          (1U << 4)
  42 #define ALTERNATE       (1U << 5)
  43
  44 static int marked;
  45
  46 /*
  47  * After sending this many "have"s if we do not get any new ACK , we
  48  * give up traversing our history.
  49  */
  50 #define MAX_IN_VAIN 256
  51
  52 static struct prio_queue rev_list = { compare_commits_by_commit_date };
  53 static int non_common_revs, 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 char *refname,
  81                                 const struct object_id *oid,
  82                                 void *vcache)
  83 {
  84         struct alternate_object_cache *cache = vcache;
  85         struct object *obj = parse_object(oid);
  86
  87         if (!obj || (obj->flags & ALTERNATE))
  88                 return;
  89
  90         obj->flags |= ALTERNATE;
  91         ALLOC_GROW(cache->items, cache->nr + 1, cache->alloc);
  92         cache->items[cache->nr++] = obj;
  93 }
  94
  95 static void for_each_cached_alternate(void (*cb)(struct object *))
  96 {
  97         static int initialized;
  98         static struct alternate_object_cache cache;
  99         size_t i;
 100
 101         if (!initialized) {
 102                 for_each_alternate_ref(cache_one_alternate, &cache);
 103                 initialized = 1;
 104         }
 105
 106         for (i = 0; i < cache.nr; i++)
 107                 cb(cache.items[i]);
 108 }
 109
 110 static void rev_list_push(struct commit *commit, int mark)
 111 {
 112         if (!(commit->object.flags & mark)) {
 113                 commit->object.flags |= mark;
 114
 115                 if (parse_commit(commit))
 116                         return;
 117
 118                 prio_queue_put(&rev_list, commit);
 119
 120                 if (!(commit->object.flags & COMMON))
 121                         non_common_revs++;
 122         }
 123 }
 124
 125 static int rev_list_insert_ref(const char *refname, const struct object_id *oid)
 126 {
 127         struct object *o = deref_tag(parse_object(oid), refname, 0);
 128
 129         if (o && o->type == OBJ_COMMIT)
 130                 rev_list_push((struct commit *)o, SEEN);
 131
 132         return 0;
 133 }
 134
 135 static int rev_list_insert_ref_oid(const char *refname, const struct object_id *oid,
 136                                    int flag, void *cb_data)
 137 {
 138         return rev_list_insert_ref(refname, oid);
 139 }
 140
 141 static int clear_marks(const char *refname, const struct object_id *oid,
 142                        int flag, void *cb_data)
 143 {
 144         struct object *o = deref_tag(parse_object(oid), refname, 0);
 145
 146         if (o && o->type == OBJ_COMMIT)
 147                 clear_commit_marks((struct commit *)o,
 148                                    COMMON | COMMON_REF | SEEN | POPPED);
 149         return 0;
 150 }
 151
 152 /*
 153    This function marks a rev and its ancestors as common.
 154    In some cases, it is desirable to mark only the ancestors (for example
 155    when only the server does not yet know that they are common).
 156 */
 157
 158 static void mark_common(struct commit *commit,
 159                 int ancestors_only, int dont_parse)
 160 {
 161         if (commit != NULL && !(commit->object.flags & COMMON)) {
 162                 struct object *o = (struct object *)commit;
 163
 164                 if (!ancestors_only)
 165                         o->flags |= COMMON;
 166
 167                 if (!(o->flags & SEEN))
 168                         rev_list_push(commit, SEEN);
 169                 else {
 170                         struct commit_list *parents;
 171
 172                         if (!ancestors_only && !(o->flags & POPPED))
 173                                 non_common_revs--;
 174                         if (!o->parsed && !dont_parse)
 175                                 if (parse_commit(commit))
 176                                         return;
 177
 178                         for (parents = commit->parents;
 179                                         parents;
 180                                         parents = parents->next)
 181                                 mark_common(parents->item, 0, dont_parse);
 182                 }
 183         }
 184 }
 185
 186 /*
 187   Get the next rev to send, ignoring the common.
 188 */
 189
 190 static const struct object_id *get_rev(void)
 191 {
 192         struct commit *commit = NULL;
 193
 194         while (commit == NULL) {
 195                 unsigned int mark;
 196                 struct commit_list *parents;
 197
 198                 if (rev_list.nr == 0 || non_common_revs == 0)
 199                         return NULL;
 200
 201                 commit = prio_queue_get(&rev_list);
 202                 parse_commit(commit);
 203                 parents = commit->parents;
 204
 205                 commit->object.flags |= POPPED;
 206                 if (!(commit->object.flags & COMMON))
 207                         non_common_revs--;
 208
 209                 if (commit->object.flags & COMMON) {
 210                         /* do not send "have", and ignore ancestors */
 211                         commit = NULL;
 212                         mark = COMMON | SEEN;
 213                 } else if (commit->object.flags & COMMON_REF)
 214                         /* send "have", and ignore ancestors */
 215                         mark = COMMON | SEEN;
 216                 else
 217                         /* send "have", also for its ancestors */
 218                         mark = SEEN;
 219
 220                 while (parents) {
 221                         if (!(parents->item->object.flags & SEEN))
 222                                 rev_list_push(parents->item, mark);
 223                         if (mark & COMMON)
 224                                 mark_common(parents->item, 1, 0);
 225                         parents = parents->next;
 226                 }
 227         }
 228
 229         return &commit->object.oid;
 230 }
 231
 232 enum ack_type {
 233         NAK = 0,
 234         ACK,
 235         ACK_continue,
 236         ACK_common,
 237         ACK_ready
 238 };
 239
 240 static void consume_shallow_list(struct fetch_pack_args *args, int fd)
 241 {
 242         if (args->stateless_rpc && args->deepen) {
 243                 /* If we sent a depth we will get back "duplicate"
 244                  * shallow and unshallow commands every time there
 245                  * is a block of have lines exchanged.
 246                  */
 247                 char *line;
 248                 while ((line = packet_read_line(fd, NULL))) {
 249                         if (starts_with(line, "shallow "))
 250                                 continue;
 251                         if (starts_with(line, "unshallow "))
 252                                 continue;
 253                         die(_("git fetch-pack: expected shallow list"));
 254                 }
 255         }
 256 }
 257
 258 static enum ack_type get_ack(int fd, struct object_id *result_oid)
 259 {
 260         int len;
 261         char *line = packet_read_line(fd, &len);
 262         const char *arg;
 263
 264         if (!line)
 265                 die(_("git fetch-pack: expected ACK/NAK, got a flush packet"));
 266         if (!strcmp(line, "NAK"))
 267                 return NAK;
 268         if (skip_prefix(line, "ACK ", &arg)) {
 269                 if (!get_oid_hex(arg, result_oid)) {
 270                         arg += 40;
 271                         len -= arg - line;
 272                         if (len < 1)
 273                                 return ACK;
 274                         if (strstr(arg, "continue"))
 275                                 return ACK_continue;
 276                         if (strstr(arg, "common"))
 277                                 return ACK_common;
 278                         if (strstr(arg, "ready"))
 279                                 return ACK_ready;
 280                         return ACK;
 281                 }
 282         }
 283         if (skip_prefix(line, "ERR ", &arg))
 284                 die(_("remote error: %s"), arg);
 285         die(_("git fetch-pack: expected ACK/NAK, got '%s'"), line);
 286 }
 287
 288 static void send_request(struct fetch_pack_args *args,
 289                          int fd, struct strbuf *buf)
 290 {
 291         if (args->stateless_rpc) {
 292                 send_sideband(fd, -1, buf->buf, buf->len, LARGE_PACKET_MAX);
 293                 packet_flush(fd);
 294         } else
 295                 write_or_die(fd, buf->buf, buf->len);
 296 }
 297
 298 static void insert_one_alternate_object(struct object *obj)
 299 {
 300         rev_list_insert_ref(NULL, &obj->oid);
 301 }
 302
 303 #define INITIAL_FLUSH 16
 304 #define PIPESAFE_FLUSH 32
 305 #define LARGE_FLUSH 16384
 306
 307 static int next_flush(struct fetch_pack_args *args, int count)
 308 {
 309         if (args->stateless_rpc) {
 310                 if (count < LARGE_FLUSH)
 311                         count <<= 1;
 312                 else
 313                         count = count * 11 / 10;
 314         } else {
 315                 if (count < PIPESAFE_FLUSH)
 316                         count <<= 1;
 317                 else
 318                         count += PIPESAFE_FLUSH;
 319         }
 320         return count;
 321 }
 322
 323 static int find_common(struct fetch_pack_args *args,
 324                        int fd[2], struct object_id *result_oid,
 325                        struct ref *refs)
 326 {
 327         int fetching;
 328         int count = 0, flushes = 0, flush_at = INITIAL_FLUSH, retval;
 329         const struct object_id *oid;
 330         unsigned in_vain = 0;
 331         int got_continue = 0;
 332         int got_ready = 0;
 333         struct strbuf req_buf = STRBUF_INIT;
 334         size_t state_len = 0;
 335
 336         if (args->stateless_rpc && multi_ack == 1)
 337                 die(_("--stateless-rpc requires multi_ack_detailed"));
 338         if (marked)
 339                 for_each_ref(clear_marks, NULL);
 340         marked = 1;
 341
 342         for_each_ref(rev_list_insert_ref_oid, NULL);
 343         for_each_cached_alternate(insert_one_alternate_object);
 344
 345         fetching = 0;
 346         for ( ; refs ; refs = refs->next) {
 347                 struct object_id *remote = &refs->old_oid;
 348                 const char *remote_hex;
 349                 struct object *o;
 350
 351                 /*
 352                  * If that object is complete (i.e. it is an ancestor of a
 353                  * local ref), we tell them we have it but do not have to
 354                  * tell them about its ancestors, which they already know
 355                  * about.
 356                  *
 357                  * We use lookup_object here because we are only
 358                  * interested in the case we *know* the object is
 359                  * reachable and we have already scanned it.
 360                  */
 361                 if (((o = lookup_object(remote->hash)) != NULL) &&
 362                                 (o->flags & COMPLETE)) {
 363                         continue;
 364                 }
 365
 366                 remote_hex = oid_to_hex(remote);
 367                 if (!fetching) {
 368                         struct strbuf c = STRBUF_INIT;
 369                         if (multi_ack == 2)     strbuf_addstr(&c, " multi_ack_detailed");
 370                         if (multi_ack == 1)     strbuf_addstr(&c, " multi_ack");
 371                         if (no_done)            strbuf_addstr(&c, " no-done");
 372                         if (use_sideband == 2)  strbuf_addstr(&c, " side-band-64k");
 373                         if (use_sideband == 1)  strbuf_addstr(&c, " side-band");
 374                         if (args->deepen_relative) strbuf_addstr(&c, " deepen-relative");
 375                         if (args->use_thin_pack) strbuf_addstr(&c, " thin-pack");
 376                         if (args->no_progress)   strbuf_addstr(&c, " no-progress");
 377                         if (args->include_tag)   strbuf_addstr(&c, " include-tag");
 378                         if (prefer_ofs_delta)   strbuf_addstr(&c, " ofs-delta");
 379                         if (deepen_since_ok)    strbuf_addstr(&c, " deepen-since");
 380                         if (deepen_not_ok)      strbuf_addstr(&c, " deepen-not");
 381                         if (agent_supported)    strbuf_addf(&c, " agent=%s",
 382                                                             git_user_agent_sanitized());
 383                         if (args->filter_options.choice)
 384                                 strbuf_addstr(&c, " filter");
 385                         packet_buf_write(&req_buf, "want %s%s\n", remote_hex, c.buf);
 386                         strbuf_release(&c);
 387                 } else
 388                         packet_buf_write(&req_buf, "want %s\n", remote_hex);
 389                 fetching++;
 390         }
 391
 392         if (!fetching) {
 393                 strbuf_release(&req_buf);
 394                 packet_flush(fd[1]);
 395                 return 1;
 396         }
 397
 398         if (is_repository_shallow())
 399                 write_shallow_commits(&req_buf, 1, NULL);
 400         if (args->depth > 0)
 401                 packet_buf_write(&req_buf, "deepen %d", args->depth);
 402         if (args->deepen_since) {
 403                 timestamp_t max_age = approxidate(args->deepen_since);
 404                 packet_buf_write(&req_buf, "deepen-since %"PRItime, max_age);
 405         }
 406         if (args->deepen_not) {
 407                 int i;
 408                 for (i = 0; i < args->deepen_not->nr; i++) {
 409                         struct string_list_item *s = args->deepen_not->items + i;
 410                         packet_buf_write(&req_buf, "deepen-not %s", s->string);
 411                 }
 412         }
 413         if (server_supports_filtering && args->filter_options.choice)
 414                 packet_buf_write(&req_buf, "filter %s",
 415                                  args->filter_options.filter_spec);
 416         packet_buf_flush(&req_buf);
 417         state_len = req_buf.len;
 418
 419         if (args->deepen) {
 420                 char *line;
 421                 const char *arg;
 422                 struct object_id oid;
 423
 424                 send_request(args, fd[1], &req_buf);
 425                 while ((line = packet_read_line(fd[0], NULL))) {
 426                         if (skip_prefix(line, "shallow ", &arg)) {
 427                                 if (get_oid_hex(arg, &oid))
 428                                         die(_("invalid shallow line: %s"), line);
 429                                 register_shallow(&oid);
 430                                 continue;
 431                         }
 432                         if (skip_prefix(line, "unshallow ", &arg)) {
 433                                 if (get_oid_hex(arg, &oid))
 434                                         die(_("invalid unshallow line: %s"), line);
 435                                 if (!lookup_object(oid.hash))
 436                                         die(_("object not found: %s"), line);
 437                                 /* make sure that it is parsed as shallow */
 438                                 if (!parse_object(&oid))
 439                                         die(_("error in object: %s"), line);
 440                                 if (unregister_shallow(&oid))
 441                                         die(_("no shallow found: %s"), line);
 442                                 continue;
 443                         }
 444                         die(_("expected shallow/unshallow, got %s"), line);
 445                 }
 446         } else if (!args->stateless_rpc)
 447                 send_request(args, fd[1], &req_buf);
 448
 449         if (!args->stateless_rpc) {
 450                 /* If we aren't using the stateless-rpc interface
 451                  * we don't need to retain the headers.
 452                  */
 453                 strbuf_setlen(&req_buf, 0);
 454                 state_len = 0;
 455         }
 456
 457         flushes = 0;
 458         retval = -1;
 459         if (args->no_dependents)
 460                 goto done;
 461         while ((oid = get_rev())) {
 462                 packet_buf_write(&req_buf, "have %s\n", oid_to_hex(oid));
 463                 print_verbose(args, "have %s", oid_to_hex(oid));
 464                 in_vain++;
 465                 if (flush_at <= ++count) {
 466                         int ack;
 467
 468                         packet_buf_flush(&req_buf);
 469                         send_request(args, fd[1], &req_buf);
 470                         strbuf_setlen(&req_buf, state_len);
 471                         flushes++;
 472                         flush_at = next_flush(args, count);
 473
 474                         /*
 475                          * We keep one window "ahead" of the other side, and
 476                          * will wait for an ACK only on the next one
 477                          */
 478                         if (!args->stateless_rpc && count == INITIAL_FLUSH)
 479                                 continue;
 480
 481                         consume_shallow_list(args, fd[0]);
 482                         do {
 483                                 ack = get_ack(fd[0], result_oid);
 484                                 if (ack)
 485                                         print_verbose(args, _("got %s %d %s"), "ack",
 486                                                       ack, oid_to_hex(result_oid));
 487                                 switch (ack) {
 488                                 case ACK:
 489                                         flushes = 0;
 490                                         multi_ack = 0;
 491                                         retval = 0;
 492                                         goto done;
 493                                 case ACK_common:
 494                                 case ACK_ready:
 495                                 case ACK_continue: {
 496                                         struct commit *commit =
 497                                                 lookup_commit(result_oid);
 498                                         if (!commit)
 499                                                 die(_("invalid commit %s"), oid_to_hex(result_oid));
 500                                         if (args->stateless_rpc
 501                                          && ack == ACK_common
 502                                          && !(commit->object.flags & COMMON)) {
 503                                                 /* We need to replay the have for this object
 504                                                  * on the next RPC request so the peer knows
 505                                                  * it is in common with us.
 506                                                  */
 507                                                 const char *hex = oid_to_hex(result_oid);
 508                                                 packet_buf_write(&req_buf, "have %s\n", hex);
 509                                                 state_len = req_buf.len;
 510                                                 /*
 511                                                  * Reset in_vain because an ack
 512                                                  * for this commit has not been
 513                                                  * seen.
 514                                                  */
 515                                                 in_vain = 0;
 516                                         } else if (!args->stateless_rpc
 517                                                    || ack != ACK_common)
 518                                                 in_vain = 0;
 519                                         mark_common(commit, 0, 1);
 520                                         retval = 0;
 521                                         got_continue = 1;
 522                                         if (ack == ACK_ready) {
 523                                                 clear_prio_queue(&rev_list);
 524                                                 got_ready = 1;
 525                                         }
 526                                         break;
 527                                         }
 528                                 }
 529                         } while (ack);
 530                         flushes--;
 531                         if (got_continue && MAX_IN_VAIN < in_vain) {
 532                                 print_verbose(args, _("giving up"));
 533                                 break; /* give up */
 534                         }
 535                 }
 536         }
 537 done:
 538         if (!got_ready || !no_done) {
 539                 packet_buf_write(&req_buf, "done\n");
 540                 send_request(args, fd[1], &req_buf);
 541         }
 542         print_verbose(args, _("done"));
 543         if (retval != 0) {
 544                 multi_ack = 0;
 545                 flushes++;
 546         }
 547         strbuf_release(&req_buf);
 548
 549         if (!got_ready || !no_done)
 550                 consume_shallow_list(args, fd[0]);
 551         while (flushes || multi_ack) {
 552                 int ack = get_ack(fd[0], result_oid);
 553                 if (ack) {
 554                         print_verbose(args, _("got %s (%d) %s"), "ack",
 555                                       ack, oid_to_hex(result_oid));
 556                         if (ack == ACK)
 557                                 return 0;
 558                         multi_ack = 1;
 559                         continue;
 560                 }
 561                 flushes--;
 562         }
 563         /* it is no error to fetch into a completely empty repo */
 564         return count ? retval : 0;
 565 }
 566
 567 static struct commit_list *complete;
 568
 569 static int mark_complete(const struct object_id *oid)
 570 {
 571         struct object *o = parse_object(oid);
 572
 573         while (o && o->type == OBJ_TAG) {
 574                 struct tag *t = (struct tag *) o;
 575                 if (!t->tagged)
 576                         break; /* broken repository */
 577                 o->flags |= COMPLETE;
 578                 o = parse_object(&t->tagged->oid);
 579         }
 580         if (o && o->type == OBJ_COMMIT) {
 581                 struct commit *commit = (struct commit *)o;
 582                 if (!(commit->object.flags & COMPLETE)) {
 583                         commit->object.flags |= COMPLETE;
 584                         commit_list_insert(commit, &complete);
 585                 }
 586         }
 587         return 0;
 588 }
 589
 590 static int mark_complete_oid(const char *refname, const struct object_id *oid,
 591                              int flag, void *cb_data)
 592 {
 593         return mark_complete(oid);
 594 }
 595
 596 static void mark_recent_complete_commits(struct fetch_pack_args *args,
 597                                          timestamp_t cutoff)
 598 {
 599         while (complete && cutoff <= complete->item->date) {
 600                 print_verbose(args, _("Marking %s as complete"),
 601                               oid_to_hex(&complete->item->object.oid));
 602                 pop_most_recent_commit(&complete, COMPLETE);
 603         }
 604 }
 605
 606 static void add_refs_to_oidset(struct oidset *oids, struct ref *refs)
 607 {
 608         for (; refs; refs = refs->next)
 609                 oidset_insert(oids, &refs->old_oid);
 610 }
 611
 612 static int tip_oids_contain(struct oidset *tip_oids,
 613                             struct ref *unmatched, struct ref *newlist,
 614                             const struct object_id *id)
 615 {
 616         /*
 617          * Note that this only looks at the ref lists the first time it's
 618          * called. This works out in filter_refs() because even though it may
 619          * add to "newlist" between calls, the additions will always be for
 620          * oids that are already in the set.
 621          */
 622         if (!tip_oids->map.map.tablesize) {
 623                 add_refs_to_oidset(tip_oids, unmatched);
 624                 add_refs_to_oidset(tip_oids, newlist);
 625         }
 626         return oidset_contains(tip_oids, id);
 627 }
 628
 629 static void filter_refs(struct fetch_pack_args *args,
 630                         struct ref **refs,
 631                         struct ref **sought, int nr_sought)
 632 {
 633         struct ref *newlist = NULL;
 634         struct ref **newtail = &newlist;
 635         struct ref *unmatched = NULL;
 636         struct ref *ref, *next;
 637         struct oidset tip_oids = OIDSET_INIT;
 638         int i;
 639
 640         i = 0;
 641         for (ref = *refs; ref; ref = next) {
 642                 int keep = 0;
 643                 next = ref->next;
 644
 645                 if (starts_with(ref->name, "refs/") &&
 646                     check_refname_format(ref->name, 0))
 647                         ; /* trash */
 648                 else {
 649                         while (i < nr_sought) {
 650                                 int cmp = strcmp(ref->name, sought[i]->name);
 651                                 if (cmp < 0)
 652                                         break; /* definitely do not have it */
 653                                 else if (cmp == 0) {
 654                                         keep = 1; /* definitely have it */
 655                                         sought[i]->match_status = REF_MATCHED;
 656                                 }
 657                                 i++;
 658                         }
 659                 }
 660
 661                 if (!keep && args->fetch_all &&
 662                     (!args->deepen || !starts_with(ref->name, "refs/tags/")))
 663                         keep = 1;
 664
 665                 if (keep) {
 666                         *newtail = ref;
 667                         ref->next = NULL;
 668                         newtail = &ref->next;
 669                 } else {
 670                         ref->next = unmatched;
 671                         unmatched = ref;
 672                 }
 673         }
 674
 675         /* Append unmatched requests to the list */
 676         for (i = 0; i < nr_sought; i++) {
 677                 struct object_id oid;
 678                 const char *p;
 679
 680                 ref = sought[i];
 681                 if (ref->match_status != REF_NOT_MATCHED)
 682                         continue;
 683                 if (parse_oid_hex(ref->name, &oid, &p) ||
 684                     *p != '\0' ||
 685                     oidcmp(&oid, &ref->old_oid))
 686                         continue;
 687
 688                 if ((allow_unadvertised_object_request &
 689                      (ALLOW_TIP_SHA1 | ALLOW_REACHABLE_SHA1)) ||
 690                     tip_oids_contain(&tip_oids, unmatched, newlist,
 691                                      &ref->old_oid)) {
 692                         ref->match_status = REF_MATCHED;
 693                         *newtail = copy_ref(ref);
 694                         newtail = &(*newtail)->next;
 695                 } else {
 696                         ref->match_status = REF_UNADVERTISED_NOT_ALLOWED;
 697                 }
 698         }
 699
 700         oidset_clear(&tip_oids);
 701         for (ref = unmatched; ref; ref = next) {
 702                 next = ref->next;
 703                 free(ref);
 704         }
 705
 706         *refs = newlist;
 707 }
 708
 709 static void mark_alternate_complete(struct object *obj)
 710 {
 711         mark_complete(&obj->oid);
 712 }
 713
 714 struct loose_object_iter {
 715         struct oidset *loose_object_set;
 716         struct ref *refs;
 717 };
 718
 719 /*
 720  *  If the number of refs is not larger than the number of loose objects,
 721  *  this function stops inserting.
 722  */
 723 static int add_loose_objects_to_set(const struct object_id *oid,
 724                                     const char *path,
 725                                     void *data)
 726 {
 727         struct loose_object_iter *iter = data;
 728         oidset_insert(iter->loose_object_set, oid);
 729         if (iter->refs == NULL)
 730                 return 1;
 731
 732         iter->refs = iter->refs->next;
 733         return 0;
 734 }
 735
 736 static int everything_local(struct fetch_pack_args *args,
 737                             struct ref **refs,
 738                             struct ref **sought, int nr_sought)
 739 {
 740         struct ref *ref;
 741         int retval;
 742         int old_save_commit_buffer = save_commit_buffer;
 743         timestamp_t cutoff = 0;
 744         struct oidset loose_oid_set = OIDSET_INIT;
 745         int use_oidset = 0;
 746         struct loose_object_iter iter = {&loose_oid_set, *refs};
 747
 748         /* Enumerate all loose objects or know refs are not so many. */
 749         use_oidset = !for_each_loose_object(add_loose_objects_to_set,
 750                                             &iter, 0);
 751
 752         save_commit_buffer = 0;
 753
 754         for (ref = *refs; ref; ref = ref->next) {
 755                 struct object *o;
 756                 unsigned int flags = OBJECT_INFO_QUICK;
 757
 758                 if (use_oidset &&
 759                     !oidset_contains(&loose_oid_set, &ref->old_oid)) {
 760                         /*
 761                          * I know this does not exist in the loose form,
 762                          * so check if it exists in a non-loose form.
 763                          */
 764                         flags |= OBJECT_INFO_IGNORE_LOOSE;
 765                 }
 766
 767                 if (!has_object_file_with_flags(&ref->old_oid, flags))
 768                         continue;
 769                 o = parse_object(&ref->old_oid);
 770                 if (!o)
 771                         continue;
 772
 773                 /* We already have it -- which may mean that we were
 774                  * in sync with the other side at some time after
 775                  * that (it is OK if we guess wrong here).
 776                  */
 777                 if (o->type == OBJ_COMMIT) {
 778                         struct commit *commit = (struct commit *)o;
 779                         if (!cutoff || cutoff < commit->date)
 780                                 cutoff = commit->date;
 781                 }
 782         }
 783
 784         oidset_clear(&loose_oid_set);
 785
 786         if (!args->no_dependents) {
 787                 if (!args->deepen) {
 788                         for_each_ref(mark_complete_oid, NULL);
 789                         for_each_cached_alternate(mark_alternate_complete);
 790                         commit_list_sort_by_date(&complete);
 791                         if (cutoff)
 792                                 mark_recent_complete_commits(args, cutoff);
 793                 }
 794
 795                 /*
 796                  * Mark all complete remote refs as common refs.
 797                  * Don't mark them common yet; the server has to be told so first.
 798                  */
 799                 for (ref = *refs; ref; ref = ref->next) {
 800                         struct object *o = deref_tag(lookup_object(ref->old_oid.hash),
 801                                                      NULL, 0);
 802
 803                         if (!o || o->type != OBJ_COMMIT || !(o->flags & COMPLETE))
 804                                 continue;
 805
 806                         if (!(o->flags & SEEN)) {
 807                                 rev_list_push((struct commit *)o, COMMON_REF | SEEN);
 808
 809                                 mark_common((struct commit *)o, 1, 1);
 810                         }
 811                 }
 812         }
 813
 814         filter_refs(args, refs, sought, nr_sought);
 815
 816         for (retval = 1, ref = *refs; ref ; ref = ref->next) {
 817                 const struct object_id *remote = &ref->old_oid;
 818                 struct object *o;
 819
 820                 o = lookup_object(remote->hash);
 821                 if (!o || !(o->flags & COMPLETE)) {
 822                         retval = 0;
 823                         print_verbose(args, "want %s (%s)", oid_to_hex(remote),
 824                                       ref->name);
 825                         continue;
 826                 }
 827                 print_verbose(args, _("already have %s (%s)"), oid_to_hex(remote),
 828                               ref->name);
 829         }
 830
 831         save_commit_buffer = old_save_commit_buffer;
 832
 833         return retval;
 834 }
 835
 836 static int sideband_demux(int in, int out, void *data)
 837 {
 838         int *xd = data;
 839         int ret;
 840
 841         ret = recv_sideband("fetch-pack", xd[0], out);
 842         close(out);
 843         return ret;
 844 }
 845
 846 static int get_pack(struct fetch_pack_args *args,
 847                     int xd[2], char **pack_lockfile)
 848 {
 849         struct async demux;
 850         int do_keep = args->keep_pack;
 851         const char *cmd_name;
 852         struct pack_header header;
 853         int pass_header = 0;
 854         struct child_process cmd = CHILD_PROCESS_INIT;
 855         int ret;
 856
 857         memset(&demux, 0, sizeof(demux));
 858         if (use_sideband) {
 859                 /* xd[] is talking with upload-pack; subprocess reads from
 860                  * xd[0], spits out band#2 to stderr, and feeds us band#1
 861                  * through demux->out.
 862                  */
 863                 demux.proc = sideband_demux;
 864                 demux.data = xd;
 865                 demux.out = -1;
 866                 demux.isolate_sigpipe = 1;
 867                 if (start_async(&demux))
 868                         die(_("fetch-pack: unable to fork off sideband demultiplexer"));
 869         }
 870         else
 871                 demux.out = xd[0];
 872
 873         if (!args->keep_pack && unpack_limit) {
 874
 875                 if (read_pack_header(demux.out, &header))
 876                         die(_("protocol error: bad pack header"));
 877                 pass_header = 1;
 878                 if (ntohl(header.hdr_entries) < unpack_limit)
 879                         do_keep = 0;
 880                 else
 881                         do_keep = 1;
 882         }
 883
 884         if (alternate_shallow_file) {
 885                 argv_array_push(&cmd.args, "--shallow-file");
 886                 argv_array_push(&cmd.args, alternate_shallow_file);
 887         }
 888
 889         if (do_keep || args->from_promisor) {
 890                 if (pack_lockfile)
 891                         cmd.out = -1;
 892                 cmd_name = "index-pack";
 893                 argv_array_push(&cmd.args, cmd_name);
 894                 argv_array_push(&cmd.args, "--stdin");
 895                 if (!args->quiet && !args->no_progress)
 896                         argv_array_push(&cmd.args, "-v");
 897                 if (args->use_thin_pack)
 898                         argv_array_push(&cmd.args, "--fix-thin");
 899                 if (do_keep && (args->lock_pack || unpack_limit)) {
 900                         char hostname[HOST_NAME_MAX + 1];
 901                         if (xgethostname(hostname, sizeof(hostname)))
 902                                 xsnprintf(hostname, sizeof(hostname), "localhost");
 903                         argv_array_pushf(&cmd.args,
 904                                         "--keep=fetch-pack %"PRIuMAX " on %s",
 905                                         (uintmax_t)getpid(), hostname);
 906                 }
 907                 if (args->check_self_contained_and_connected)
 908                         argv_array_push(&cmd.args, "--check-self-contained-and-connected");
 909                 if (args->from_promisor)
 910                         argv_array_push(&cmd.args, "--promisor");
 911         }
 912         else {
 913                 cmd_name = "unpack-objects";
 914                 argv_array_push(&cmd.args, cmd_name);
 915                 if (args->quiet || args->no_progress)
 916                         argv_array_push(&cmd.args, "-q");
 917                 args->check_self_contained_and_connected = 0;
 918         }
 919
 920         if (pass_header)
 921                 argv_array_pushf(&cmd.args, "--pack_header=%"PRIu32",%"PRIu32,
 922                                  ntohl(header.hdr_version),
 923                                  ntohl(header.hdr_entries));
 924         if (fetch_fsck_objects >= 0
 925             ? fetch_fsck_objects
 926             : transfer_fsck_objects >= 0
 927             ? transfer_fsck_objects
 928             : 0) {
 929                 if (args->from_promisor)
 930                         /*
 931                          * We cannot use --strict in index-pack because it
 932                          * checks both broken objects and links, but we only
 933                          * want to check for broken objects.
 934                          */
 935                         argv_array_push(&cmd.args, "--fsck-objects");
 936                 else
 937                         argv_array_push(&cmd.args, "--strict");
 938         }
 939
 940         cmd.in = demux.out;
 941         cmd.git_cmd = 1;
 942         if (start_command(&cmd))
 943                 die(_("fetch-pack: unable to fork off %s"), cmd_name);
 944         if (do_keep && pack_lockfile) {
 945                 *pack_lockfile = index_pack_lockfile(cmd.out);
 946                 close(cmd.out);
 947         }
 948
 949         if (!use_sideband)
 950                 /* Closed by start_command() */
 951                 xd[0] = -1;
 952
 953         ret = finish_command(&cmd);
 954         if (!ret || (args->check_self_contained_and_connected && ret == 1))
 955                 args->self_contained_and_connected =
 956                         args->check_self_contained_and_connected &&
 957                         ret == 0;
 958         else
 959                 die(_("%s failed"), cmd_name);
 960         if (use_sideband && finish_async(&demux))
 961                 die(_("error in sideband demultiplexer"));
 962         return 0;
 963 }
 964
 965 static int cmp_ref_by_name(const void *a_, const void *b_)
 966 {
 967         const struct ref *a = *((const struct ref **)a_);
 968         const struct ref *b = *((const struct ref **)b_);
 969         return strcmp(a->name, b->name);
 970 }
 971
 972 static struct ref *do_fetch_pack(struct fetch_pack_args *args,
 973                                  int fd[2],
 974                                  const struct ref *orig_ref,
 975                                  struct ref **sought, int nr_sought,
 976                                  struct shallow_info *si,
 977                                  char **pack_lockfile)
 978 {
 979         struct ref *ref = copy_ref_list(orig_ref);
 980         struct object_id oid;
 981         const char *agent_feature;
 982         int agent_len;
 983
 984         sort_ref_list(&ref, ref_compare_name);
 985         QSORT(sought, nr_sought, cmp_ref_by_name);
 986
 987         if ((args->depth > 0 || is_repository_shallow()) && !server_supports("shallow"))
 988                 die(_("Server does not support shallow clients"));
 989         if (args->depth > 0 || args->deepen_since || args->deepen_not)
 990                 args->deepen = 1;
 991         if (server_supports("multi_ack_detailed")) {
 992                 print_verbose(args, _("Server supports multi_ack_detailed"));
 993                 multi_ack = 2;
 994                 if (server_supports("no-done")) {
 995                         print_verbose(args, _("Server supports no-done"));
 996                         if (args->stateless_rpc)
 997                                 no_done = 1;
 998                 }
 999         }
1000         else if (server_supports("multi_ack")) {
1001                 print_verbose(args, _("Server supports multi_ack"));
1002                 multi_ack = 1;
1003         }
1004         if (server_supports("side-band-64k")) {
1005                 print_verbose(args, _("Server supports side-band-64k"));
1006                 use_sideband = 2;
1007         }
1008         else if (server_supports("side-band")) {
1009                 print_verbose(args, _("Server supports side-band"));
1010                 use_sideband = 1;
1011         }
1012         if (server_supports("allow-tip-sha1-in-want")) {
1013                 print_verbose(args, _("Server supports allow-tip-sha1-in-want"));
1014                 allow_unadvertised_object_request |= ALLOW_TIP_SHA1;
1015         }
1016         if (server_supports("allow-reachable-sha1-in-want")) {
1017                 print_verbose(args, _("Server supports allow-reachable-sha1-in-want"));
1018                 allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
1019         }
1020         if (!server_supports("thin-pack"))
1021                 args->use_thin_pack = 0;
1022         if (!server_supports("no-progress"))
1023                 args->no_progress = 0;
1024         if (!server_supports("include-tag"))
1025                 args->include_tag = 0;
1026         if (server_supports("ofs-delta"))
1027                 print_verbose(args, _("Server supports ofs-delta"));
1028         else
1029                 prefer_ofs_delta = 0;
1030
1031         if (server_supports("filter")) {
1032                 server_supports_filtering = 1;
1033                 print_verbose(args, _("Server supports filter"));
1034         } else if (args->filter_options.choice) {
1035                 warning("filtering not recognized by server, ignoring");
1036         }
1037
1038         if ((agent_feature = server_feature_value("agent", &agent_len))) {
1039                 agent_supported = 1;
1040                 if (agent_len)
1041                         print_verbose(args, _("Server version is %.*s"),
1042                                       agent_len, agent_feature);
1043         }
1044         if (server_supports("deepen-since"))
1045                 deepen_since_ok = 1;
1046         else if (args->deepen_since)
1047                 die(_("Server does not support --shallow-since"));
1048         if (server_supports("deepen-not"))
1049                 deepen_not_ok = 1;
1050         else if (args->deepen_not)
1051                 die(_("Server does not support --shallow-exclude"));
1052         if (!server_supports("deepen-relative") && args->deepen_relative)
1053                 die(_("Server does not support --deepen"));
1054
1055         if (everything_local(args, &ref, sought, nr_sought)) {
1056                 packet_flush(fd[1]);
1057                 goto all_done;
1058         }
1059         if (find_common(args, fd, &oid, ref) < 0)
1060                 if (!args->keep_pack)
1061                         /* When cloning, it is not unusual to have
1062                          * no common commit.
1063                          */
1064                         warning(_("no common commits"));
1065
1066         if (args->stateless_rpc)
1067                 packet_flush(fd[1]);
1068         if (args->deepen)
1069                 setup_alternate_shallow(&shallow_lock, &alternate_shallow_file,
1070                                         NULL);
1071         else if (si->nr_ours || si->nr_theirs)
1072                 alternate_shallow_file = setup_temporary_shallow(si->shallow);
1073         else
1074                 alternate_shallow_file = NULL;
1075         if (get_pack(args, fd, pack_lockfile))
1076                 die(_("git fetch-pack: fetch failed."));
1077
1078  all_done:
1079         return ref;
1080 }
1081
1082 static void fetch_pack_config(void)
1083 {
1084         git_config_get_int("fetch.unpacklimit", &fetch_unpack_limit);
1085         git_config_get_int("transfer.unpacklimit", &transfer_unpack_limit);
1086         git_config_get_bool("repack.usedeltabaseoffset", &prefer_ofs_delta);
1087         git_config_get_bool("fetch.fsckobjects", &fetch_fsck_objects);
1088         git_config_get_bool("transfer.fsckobjects", &transfer_fsck_objects);
1089
1090         git_config(git_default_config, NULL);
1091 }
1092
1093 static void fetch_pack_setup(void)
1094 {
1095         static int did_setup;
1096         if (did_setup)
1097                 return;
1098         fetch_pack_config();
1099         if (0 <= transfer_unpack_limit)
1100                 unpack_limit = transfer_unpack_limit;
1101         else if (0 <= fetch_unpack_limit)
1102                 unpack_limit = fetch_unpack_limit;
1103         did_setup = 1;
1104 }
1105
1106 static int remove_duplicates_in_refs(struct ref **ref, int nr)
1107 {
1108         struct string_list names = STRING_LIST_INIT_NODUP;
1109         int src, dst;
1110
1111         for (src = dst = 0; src < nr; src++) {
1112                 struct string_list_item *item;
1113                 item = string_list_insert(&names, ref[src]->name);
1114                 if (item->util)
1115                         continue; /* already have it */
1116                 item->util = ref[src];
1117                 if (src != dst)
1118                         ref[dst] = ref[src];
1119                 dst++;
1120         }
1121         for (src = dst; src < nr; src++)
1122                 ref[src] = NULL;
1123         string_list_clear(&names, 0);
1124         return dst;
1125 }
1126
1127 static void update_shallow(struct fetch_pack_args *args,
1128                            struct ref **sought, int nr_sought,
1129                            struct shallow_info *si)
1130 {
1131         struct oid_array ref = OID_ARRAY_INIT;
1132         int *status;
1133         int i;
1134
1135         if (args->deepen && alternate_shallow_file) {
1136                 if (*alternate_shallow_file == '\0') { /* --unshallow */
1137                         unlink_or_warn(git_path_shallow());
1138                         rollback_lock_file(&shallow_lock);
1139                 } else
1140                         commit_lock_file(&shallow_lock);
1141                 return;
1142         }
1143
1144         if (!si->shallow || !si->shallow->nr)
1145                 return;
1146
1147         if (args->cloning) {
1148                 /*
1149                  * remote is shallow, but this is a clone, there are
1150                  * no objects in repo to worry about. Accept any
1151                  * shallow points that exist in the pack (iow in repo
1152                  * after get_pack() and reprepare_packed_git())
1153                  */
1154                 struct oid_array extra = OID_ARRAY_INIT;
1155                 struct object_id *oid = si->shallow->oid;
1156                 for (i = 0; i < si->shallow->nr; i++)
1157                         if (has_object_file(&oid[i]))
1158                                 oid_array_append(&extra, &oid[i]);
1159                 if (extra.nr) {
1160                         setup_alternate_shallow(&shallow_lock,
1161                                                 &alternate_shallow_file,
1162                                                 &extra);
1163                         commit_lock_file(&shallow_lock);
1164                 }
1165                 oid_array_clear(&extra);
1166                 return;
1167         }
1168
1169         if (!si->nr_ours && !si->nr_theirs)
1170                 return;
1171
1172         remove_nonexistent_theirs_shallow(si);
1173         if (!si->nr_ours && !si->nr_theirs)
1174                 return;
1175         for (i = 0; i < nr_sought; i++)
1176                 oid_array_append(&ref, &sought[i]->old_oid);
1177         si->ref = &ref;
1178
1179         if (args->update_shallow) {
1180                 /*
1181                  * remote is also shallow, .git/shallow may be updated
1182                  * so all refs can be accepted. Make sure we only add
1183                  * shallow roots that are actually reachable from new
1184                  * refs.
1185                  */
1186                 struct oid_array extra = OID_ARRAY_INIT;
1187                 struct object_id *oid = si->shallow->oid;
1188                 assign_shallow_commits_to_refs(si, NULL, NULL);
1189                 if (!si->nr_ours && !si->nr_theirs) {
1190                         oid_array_clear(&ref);
1191                         return;
1192                 }
1193                 for (i = 0; i < si->nr_ours; i++)
1194                         oid_array_append(&extra, &oid[si->ours[i]]);
1195                 for (i = 0; i < si->nr_theirs; i++)
1196                         oid_array_append(&extra, &oid[si->theirs[i]]);
1197                 setup_alternate_shallow(&shallow_lock,
1198                                         &alternate_shallow_file,
1199                                         &extra);
1200                 commit_lock_file(&shallow_lock);
1201                 oid_array_clear(&extra);
1202                 oid_array_clear(&ref);
1203                 return;
1204         }
1205
1206         /*
1207          * remote is also shallow, check what ref is safe to update
1208          * without updating .git/shallow
1209          */
1210         status = xcalloc(nr_sought, sizeof(*status));
1211         assign_shallow_commits_to_refs(si, NULL, status);
1212         if (si->nr_ours || si->nr_theirs) {
1213                 for (i = 0; i < nr_sought; i++)
1214                         if (status[i])
1215                                 sought[i]->status = REF_STATUS_REJECT_SHALLOW;
1216         }
1217         free(status);
1218         oid_array_clear(&ref);
1219 }
1220
1221 struct ref *fetch_pack(struct fetch_pack_args *args,
1222                        int fd[], struct child_process *conn,
1223                        const struct ref *ref,
1224                        const char *dest,
1225                        struct ref **sought, int nr_sought,
1226                        struct oid_array *shallow,
1227                        char **pack_lockfile)
1228 {
1229         struct ref *ref_cpy;
1230         struct shallow_info si;
1231
1232         fetch_pack_setup();
1233         if (nr_sought)
1234                 nr_sought = remove_duplicates_in_refs(sought, nr_sought);
1235
1236         if (!ref) {
1237                 packet_flush(fd[1]);
1238                 die(_("no matching remote head"));
1239         }
1240         prepare_shallow_info(&si, shallow);
1241         ref_cpy = do_fetch_pack(args, fd, ref, sought, nr_sought,
1242                                 &si, pack_lockfile);
1243         reprepare_packed_git();
1244         update_shallow(args, sought, nr_sought, &si);
1245         clear_shallow_info(&si);
1246         return ref_cpy;
1247 }
1248
1249 int report_unmatched_refs(struct ref **sought, int nr_sought)
1250 {
1251         int i, ret = 0;
1252
1253         for (i = 0; i < nr_sought; i++) {
1254                 if (!sought[i])
1255                         continue;
1256                 switch (sought[i]->match_status) {
1257                 case REF_MATCHED:
1258                         continue;
1259                 case REF_NOT_MATCHED:
1260                         error(_("no such remote ref %s"), sought[i]->name);
1261                         break;
1262                 case REF_UNADVERTISED_NOT_ALLOWED:
1263                         error(_("Server does not allow request for unadvertised object %s"),
1264                               sought[i]->name);
1265                         break;
1266                 }
1267                 ret = 1;
1268         }
1269         return ret;
1270 }