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 (!len)
 265                 die(_("git fetch-pack: expected ACK/NAK, got EOF"));
 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 static int everything_local(struct fetch_pack_args *args,
 715                             struct ref **refs,
 716                             struct ref **sought, int nr_sought)
 717 {
 718         struct ref *ref;
 719         int retval;
 720         int old_save_commit_buffer = save_commit_buffer;
 721         timestamp_t cutoff = 0;
 722
 723         save_commit_buffer = 0;
 724
 725         for (ref = *refs; ref; ref = ref->next) {
 726                 struct object *o;
 727
 728                 if (!has_object_file_with_flags(&ref->old_oid,
 729                                                 OBJECT_INFO_QUICK))
 730                         continue;
 731
 732                 o = parse_object(&ref->old_oid);
 733                 if (!o)
 734                         continue;
 735
 736                 /* We already have it -- which may mean that we were
 737                  * in sync with the other side at some time after
 738                  * that (it is OK if we guess wrong here).
 739                  */
 740                 if (o->type == OBJ_COMMIT) {
 741                         struct commit *commit = (struct commit *)o;
 742                         if (!cutoff || cutoff < commit->date)
 743                                 cutoff = commit->date;
 744                 }
 745         }
 746
 747         if (!args->no_dependents) {
 748                 if (!args->deepen) {
 749                         for_each_ref(mark_complete_oid, NULL);
 750                         for_each_cached_alternate(mark_alternate_complete);
 751                         commit_list_sort_by_date(&complete);
 752                         if (cutoff)
 753                                 mark_recent_complete_commits(args, cutoff);
 754                 }
 755
 756                 /*
 757                  * Mark all complete remote refs as common refs.
 758                  * Don't mark them common yet; the server has to be told so first.
 759                  */
 760                 for (ref = *refs; ref; ref = ref->next) {
 761                         struct object *o = deref_tag(lookup_object(ref->old_oid.hash),
 762                                                      NULL, 0);
 763
 764                         if (!o || o->type != OBJ_COMMIT || !(o->flags & COMPLETE))
 765                                 continue;
 766
 767                         if (!(o->flags & SEEN)) {
 768                                 rev_list_push((struct commit *)o, COMMON_REF | SEEN);
 769
 770                                 mark_common((struct commit *)o, 1, 1);
 771                         }
 772                 }
 773         }
 774
 775         filter_refs(args, refs, sought, nr_sought);
 776
 777         for (retval = 1, ref = *refs; ref ; ref = ref->next) {
 778                 const struct object_id *remote = &ref->old_oid;
 779                 struct object *o;
 780
 781                 o = lookup_object(remote->hash);
 782                 if (!o || !(o->flags & COMPLETE)) {
 783                         retval = 0;
 784                         print_verbose(args, "want %s (%s)", oid_to_hex(remote),
 785                                       ref->name);
 786                         continue;
 787                 }
 788                 print_verbose(args, _("already have %s (%s)"), oid_to_hex(remote),
 789                               ref->name);
 790         }
 791
 792         save_commit_buffer = old_save_commit_buffer;
 793
 794         return retval;
 795 }
 796
 797 static int sideband_demux(int in, int out, void *data)
 798 {
 799         int *xd = data;
 800         int ret;
 801
 802         ret = recv_sideband("fetch-pack", xd[0], out);
 803         close(out);
 804         return ret;
 805 }
 806
 807 static int get_pack(struct fetch_pack_args *args,
 808                     int xd[2], char **pack_lockfile)
 809 {
 810         struct async demux;
 811         int do_keep = args->keep_pack;
 812         const char *cmd_name;
 813         struct pack_header header;
 814         int pass_header = 0;
 815         struct child_process cmd = CHILD_PROCESS_INIT;
 816         int ret;
 817
 818         memset(&demux, 0, sizeof(demux));
 819         if (use_sideband) {
 820                 /* xd[] is talking with upload-pack; subprocess reads from
 821                  * xd[0], spits out band#2 to stderr, and feeds us band#1
 822                  * through demux->out.
 823                  */
 824                 demux.proc = sideband_demux;
 825                 demux.data = xd;
 826                 demux.out = -1;
 827                 demux.isolate_sigpipe = 1;
 828                 if (start_async(&demux))
 829                         die(_("fetch-pack: unable to fork off sideband demultiplexer"));
 830         }
 831         else
 832                 demux.out = xd[0];
 833
 834         if (!args->keep_pack && unpack_limit) {
 835
 836                 if (read_pack_header(demux.out, &header))
 837                         die(_("protocol error: bad pack header"));
 838                 pass_header = 1;
 839                 if (ntohl(header.hdr_entries) < unpack_limit)
 840                         do_keep = 0;
 841                 else
 842                         do_keep = 1;
 843         }
 844
 845         if (alternate_shallow_file) {
 846                 argv_array_push(&cmd.args, "--shallow-file");
 847                 argv_array_push(&cmd.args, alternate_shallow_file);
 848         }
 849
 850         if (do_keep || args->from_promisor) {
 851                 if (pack_lockfile)
 852                         cmd.out = -1;
 853                 cmd_name = "index-pack";
 854                 argv_array_push(&cmd.args, cmd_name);
 855                 argv_array_push(&cmd.args, "--stdin");
 856                 if (!args->quiet && !args->no_progress)
 857                         argv_array_push(&cmd.args, "-v");
 858                 if (args->use_thin_pack)
 859                         argv_array_push(&cmd.args, "--fix-thin");
 860                 if (do_keep && (args->lock_pack || unpack_limit)) {
 861                         char hostname[HOST_NAME_MAX + 1];
 862                         if (xgethostname(hostname, sizeof(hostname)))
 863                                 xsnprintf(hostname, sizeof(hostname), "localhost");
 864                         argv_array_pushf(&cmd.args,
 865                                         "--keep=fetch-pack %"PRIuMAX " on %s",
 866                                         (uintmax_t)getpid(), hostname);
 867                 }
 868                 if (args->check_self_contained_and_connected)
 869                         argv_array_push(&cmd.args, "--check-self-contained-and-connected");
 870                 if (args->from_promisor)
 871                         argv_array_push(&cmd.args, "--promisor");
 872         }
 873         else {
 874                 cmd_name = "unpack-objects";
 875                 argv_array_push(&cmd.args, cmd_name);
 876                 if (args->quiet || args->no_progress)
 877                         argv_array_push(&cmd.args, "-q");
 878                 args->check_self_contained_and_connected = 0;
 879         }
 880
 881         if (pass_header)
 882                 argv_array_pushf(&cmd.args, "--pack_header=%"PRIu32",%"PRIu32,
 883                                  ntohl(header.hdr_version),
 884                                  ntohl(header.hdr_entries));
 885         if (fetch_fsck_objects >= 0
 886             ? fetch_fsck_objects
 887             : transfer_fsck_objects >= 0
 888             ? transfer_fsck_objects
 889             : 0)
 890                 argv_array_push(&cmd.args, "--strict");
 891
 892         cmd.in = demux.out;
 893         cmd.git_cmd = 1;
 894         if (start_command(&cmd))
 895                 die(_("fetch-pack: unable to fork off %s"), cmd_name);
 896         if (do_keep && pack_lockfile) {
 897                 *pack_lockfile = index_pack_lockfile(cmd.out);
 898                 close(cmd.out);
 899         }
 900
 901         if (!use_sideband)
 902                 /* Closed by start_command() */
 903                 xd[0] = -1;
 904
 905         ret = finish_command(&cmd);
 906         if (!ret || (args->check_self_contained_and_connected && ret == 1))
 907                 args->self_contained_and_connected =
 908                         args->check_self_contained_and_connected &&
 909                         ret == 0;
 910         else
 911                 die(_("%s failed"), cmd_name);
 912         if (use_sideband && finish_async(&demux))
 913                 die(_("error in sideband demultiplexer"));
 914         return 0;
 915 }
 916
 917 static int cmp_ref_by_name(const void *a_, const void *b_)
 918 {
 919         const struct ref *a = *((const struct ref **)a_);
 920         const struct ref *b = *((const struct ref **)b_);
 921         return strcmp(a->name, b->name);
 922 }
 923
 924 static struct ref *do_fetch_pack(struct fetch_pack_args *args,
 925                                  int fd[2],
 926                                  const struct ref *orig_ref,
 927                                  struct ref **sought, int nr_sought,
 928                                  struct shallow_info *si,
 929                                  char **pack_lockfile)
 930 {
 931         struct ref *ref = copy_ref_list(orig_ref);
 932         struct object_id oid;
 933         const char *agent_feature;
 934         int agent_len;
 935
 936         sort_ref_list(&ref, ref_compare_name);
 937         QSORT(sought, nr_sought, cmp_ref_by_name);
 938
 939         if ((args->depth > 0 || is_repository_shallow()) && !server_supports("shallow"))
 940                 die(_("Server does not support shallow clients"));
 941         if (args->depth > 0 || args->deepen_since || args->deepen_not)
 942                 args->deepen = 1;
 943         if (server_supports("multi_ack_detailed")) {
 944                 print_verbose(args, _("Server supports multi_ack_detailed"));
 945                 multi_ack = 2;
 946                 if (server_supports("no-done")) {
 947                         print_verbose(args, _("Server supports no-done"));
 948                         if (args->stateless_rpc)
 949                                 no_done = 1;
 950                 }
 951         }
 952         else if (server_supports("multi_ack")) {
 953                 print_verbose(args, _("Server supports multi_ack"));
 954                 multi_ack = 1;
 955         }
 956         if (server_supports("side-band-64k")) {
 957                 print_verbose(args, _("Server supports side-band-64k"));
 958                 use_sideband = 2;
 959         }
 960         else if (server_supports("side-band")) {
 961                 print_verbose(args, _("Server supports side-band"));
 962                 use_sideband = 1;
 963         }
 964         if (server_supports("allow-tip-sha1-in-want")) {
 965                 print_verbose(args, _("Server supports allow-tip-sha1-in-want"));
 966                 allow_unadvertised_object_request |= ALLOW_TIP_SHA1;
 967         }
 968         if (server_supports("allow-reachable-sha1-in-want")) {
 969                 print_verbose(args, _("Server supports allow-reachable-sha1-in-want"));
 970                 allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
 971         }
 972         if (!server_supports("thin-pack"))
 973                 args->use_thin_pack = 0;
 974         if (!server_supports("no-progress"))
 975                 args->no_progress = 0;
 976         if (!server_supports("include-tag"))
 977                 args->include_tag = 0;
 978         if (server_supports("ofs-delta"))
 979                 print_verbose(args, _("Server supports ofs-delta"));
 980         else
 981                 prefer_ofs_delta = 0;
 982
 983         if (server_supports("filter")) {
 984                 server_supports_filtering = 1;
 985                 print_verbose(args, _("Server supports filter"));
 986         } else if (args->filter_options.choice) {
 987                 warning("filtering not recognized by server, ignoring");
 988         }
 989
 990         if ((agent_feature = server_feature_value("agent", &agent_len))) {
 991                 agent_supported = 1;
 992                 if (agent_len)
 993                         print_verbose(args, _("Server version is %.*s"),
 994                                       agent_len, agent_feature);
 995         }
 996         if (server_supports("deepen-since"))
 997                 deepen_since_ok = 1;
 998         else if (args->deepen_since)
 999                 die(_("Server does not support --shallow-since"));
1000         if (server_supports("deepen-not"))
1001                 deepen_not_ok = 1;
1002         else if (args->deepen_not)
1003                 die(_("Server does not support --shallow-exclude"));
1004         if (!server_supports("deepen-relative") && args->deepen_relative)
1005                 die(_("Server does not support --deepen"));
1006
1007         if (everything_local(args, &ref, sought, nr_sought)) {
1008                 packet_flush(fd[1]);
1009                 goto all_done;
1010         }
1011         if (find_common(args, fd, &oid, ref) < 0)
1012                 if (!args->keep_pack)
1013                         /* When cloning, it is not unusual to have
1014                          * no common commit.
1015                          */
1016                         warning(_("no common commits"));
1017
1018         if (args->stateless_rpc)
1019                 packet_flush(fd[1]);
1020         if (args->deepen)
1021                 setup_alternate_shallow(&shallow_lock, &alternate_shallow_file,
1022                                         NULL);
1023         else if (si->nr_ours || si->nr_theirs)
1024                 alternate_shallow_file = setup_temporary_shallow(si->shallow);
1025         else
1026                 alternate_shallow_file = NULL;
1027         if (get_pack(args, fd, pack_lockfile))
1028                 die(_("git fetch-pack: fetch failed."));
1029
1030  all_done:
1031         return ref;
1032 }
1033
1034 static void fetch_pack_config(void)
1035 {
1036         git_config_get_int("fetch.unpacklimit", &fetch_unpack_limit);
1037         git_config_get_int("transfer.unpacklimit", &transfer_unpack_limit);
1038         git_config_get_bool("repack.usedeltabaseoffset", &prefer_ofs_delta);
1039         git_config_get_bool("fetch.fsckobjects", &fetch_fsck_objects);
1040         git_config_get_bool("transfer.fsckobjects", &transfer_fsck_objects);
1041
1042         git_config(git_default_config, NULL);
1043 }
1044
1045 static void fetch_pack_setup(void)
1046 {
1047         static int did_setup;
1048         if (did_setup)
1049                 return;
1050         fetch_pack_config();
1051         if (0 <= transfer_unpack_limit)
1052                 unpack_limit = transfer_unpack_limit;
1053         else if (0 <= fetch_unpack_limit)
1054                 unpack_limit = fetch_unpack_limit;
1055         did_setup = 1;
1056 }
1057
1058 static int remove_duplicates_in_refs(struct ref **ref, int nr)
1059 {
1060         struct string_list names = STRING_LIST_INIT_NODUP;
1061         int src, dst;
1062
1063         for (src = dst = 0; src < nr; src++) {
1064                 struct string_list_item *item;
1065                 item = string_list_insert(&names, ref[src]->name);
1066                 if (item->util)
1067                         continue; /* already have it */
1068                 item->util = ref[src];
1069                 if (src != dst)
1070                         ref[dst] = ref[src];
1071                 dst++;
1072         }
1073         for (src = dst; src < nr; src++)
1074                 ref[src] = NULL;
1075         string_list_clear(&names, 0);
1076         return dst;
1077 }
1078
1079 static void update_shallow(struct fetch_pack_args *args,
1080                            struct ref **sought, int nr_sought,
1081                            struct shallow_info *si)
1082 {
1083         struct oid_array ref = OID_ARRAY_INIT;
1084         int *status;
1085         int i;
1086
1087         if (args->deepen && alternate_shallow_file) {
1088                 if (*alternate_shallow_file == '\0') { /* --unshallow */
1089                         unlink_or_warn(git_path_shallow());
1090                         rollback_lock_file(&shallow_lock);
1091                 } else
1092                         commit_lock_file(&shallow_lock);
1093                 return;
1094         }
1095
1096         if (!si->shallow || !si->shallow->nr)
1097                 return;
1098
1099         if (args->cloning) {
1100                 /*
1101                  * remote is shallow, but this is a clone, there are
1102                  * no objects in repo to worry about. Accept any
1103                  * shallow points that exist in the pack (iow in repo
1104                  * after get_pack() and reprepare_packed_git())
1105                  */
1106                 struct oid_array extra = OID_ARRAY_INIT;
1107                 struct object_id *oid = si->shallow->oid;
1108                 for (i = 0; i < si->shallow->nr; i++)
1109                         if (has_object_file(&oid[i]))
1110                                 oid_array_append(&extra, &oid[i]);
1111                 if (extra.nr) {
1112                         setup_alternate_shallow(&shallow_lock,
1113                                                 &alternate_shallow_file,
1114                                                 &extra);
1115                         commit_lock_file(&shallow_lock);
1116                 }
1117                 oid_array_clear(&extra);
1118                 return;
1119         }
1120
1121         if (!si->nr_ours && !si->nr_theirs)
1122                 return;
1123
1124         remove_nonexistent_theirs_shallow(si);
1125         if (!si->nr_ours && !si->nr_theirs)
1126                 return;
1127         for (i = 0; i < nr_sought; i++)
1128                 oid_array_append(&ref, &sought[i]->old_oid);
1129         si->ref = &ref;
1130
1131         if (args->update_shallow) {
1132                 /*
1133                  * remote is also shallow, .git/shallow may be updated
1134                  * so all refs can be accepted. Make sure we only add
1135                  * shallow roots that are actually reachable from new
1136                  * refs.
1137                  */
1138                 struct oid_array extra = OID_ARRAY_INIT;
1139                 struct object_id *oid = si->shallow->oid;
1140                 assign_shallow_commits_to_refs(si, NULL, NULL);
1141                 if (!si->nr_ours && !si->nr_theirs) {
1142                         oid_array_clear(&ref);
1143                         return;
1144                 }
1145                 for (i = 0; i < si->nr_ours; i++)
1146                         oid_array_append(&extra, &oid[si->ours[i]]);
1147                 for (i = 0; i < si->nr_theirs; i++)
1148                         oid_array_append(&extra, &oid[si->theirs[i]]);
1149                 setup_alternate_shallow(&shallow_lock,
1150                                         &alternate_shallow_file,
1151                                         &extra);
1152                 commit_lock_file(&shallow_lock);
1153                 oid_array_clear(&extra);
1154                 oid_array_clear(&ref);
1155                 return;
1156         }
1157
1158         /*
1159          * remote is also shallow, check what ref is safe to update
1160          * without updating .git/shallow
1161          */
1162         status = xcalloc(nr_sought, sizeof(*status));
1163         assign_shallow_commits_to_refs(si, NULL, status);
1164         if (si->nr_ours || si->nr_theirs) {
1165                 for (i = 0; i < nr_sought; i++)
1166                         if (status[i])
1167                                 sought[i]->status = REF_STATUS_REJECT_SHALLOW;
1168         }
1169         free(status);
1170         oid_array_clear(&ref);
1171 }
1172
1173 struct ref *fetch_pack(struct fetch_pack_args *args,
1174                        int fd[], struct child_process *conn,
1175                        const struct ref *ref,
1176                        const char *dest,
1177                        struct ref **sought, int nr_sought,
1178                        struct oid_array *shallow,
1179                        char **pack_lockfile)
1180 {
1181         struct ref *ref_cpy;
1182         struct shallow_info si;
1183
1184         fetch_pack_setup();
1185         if (nr_sought)
1186                 nr_sought = remove_duplicates_in_refs(sought, nr_sought);
1187
1188         if (!ref) {
1189                 packet_flush(fd[1]);
1190                 die(_("no matching remote head"));
1191         }
1192         prepare_shallow_info(&si, shallow);
1193         ref_cpy = do_fetch_pack(args, fd, ref, sought, nr_sought,
1194                                 &si, pack_lockfile);
1195         reprepare_packed_git();
1196         update_shallow(args, sought, nr_sought, &si);
1197         clear_shallow_info(&si);
1198         return ref_cpy;
1199 }
1200
1201 int report_unmatched_refs(struct ref **sought, int nr_sought)
1202 {
1203         int i, ret = 0;
1204
1205         for (i = 0; i < nr_sought; i++) {
1206                 if (!sought[i])
1207                         continue;
1208                 switch (sought[i]->match_status) {
1209                 case REF_MATCHED:
1210                         continue;
1211                 case REF_NOT_MATCHED:
1212                         error(_("no such remote ref %s"), sought[i]->name);
1213                         break;
1214                 case REF_UNADVERTISED_NOT_ALLOWED:
1215                         error(_("Server does not allow request for unadvertised object %s"),
1216                               sought[i]->name);
1217                         break;
1218                 }
1219                 ret = 1;
1220         }
1221         return ret;
1222 }