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