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 struct lock_file shallow_lock;
  33 static const char *alternate_shallow_file;
  34
  35 /* Remember to update object flag allocation in object.h */
  36 #define COMPLETE        (1U << 0)
  37 #define COMMON          (1U << 1)
  38 #define COMMON_REF      (1U << 2)
  39 #define SEEN            (1U << 3)
  40 #define POPPED          (1U << 4)
  41 #define ALTERNATE       (1U << 5)
  42
  43 static int marked;
  44
  45 /*
  46  * After sending this many "have"s if we do not get any new ACK , we
  47  * give up traversing our history.
  48  */
  49 #define MAX_IN_VAIN 256
  50
  51 static struct prio_queue rev_list = { compare_commits_by_commit_date };
  52 static int non_common_revs, multi_ack, use_sideband;
  53 /* Allow specifying sha1 if it is a ref tip. */
  54 #define ALLOW_TIP_SHA1  01
  55 /* Allow request of a sha1 if it is reachable from a ref (possibly hidden ref). */
  56 #define ALLOW_REACHABLE_SHA1    02
  57 static unsigned int allow_unadvertised_object_request;
  58
  59 __attribute__((format (printf, 2, 3)))
  60 static inline void print_verbose(const struct fetch_pack_args *args,
  61                                  const char *fmt, ...)
  62 {
  63         va_list params;
  64
  65         if (!args->verbose)
  66                 return;
  67
  68         va_start(params, fmt);
  69         vfprintf(stderr, fmt, params);
  70         va_end(params);
  71         fputc('\n', stderr);
  72 }
  73
  74 struct alternate_object_cache {
  75         struct object **items;
  76         size_t nr, alloc;
  77 };
  78
  79 static void cache_one_alternate(const char *refname,
  80                                 const struct object_id *oid,
  81                                 void *vcache)
  82 {
  83         struct alternate_object_cache *cache = vcache;
  84         struct object *obj = parse_object(oid);
  85
  86         if (!obj || (obj->flags & ALTERNATE))
  87                 return;
  88
  89         obj->flags |= ALTERNATE;
  90         ALLOC_GROW(cache->items, cache->nr + 1, cache->alloc);
  91         cache->items[cache->nr++] = obj;
  92 }
  93
  94 static void for_each_cached_alternate(void (*cb)(struct object *))
  95 {
  96         static int initialized;
  97         static struct alternate_object_cache cache;
  98         size_t i;
  99
 100         if (!initialized) {
 101                 for_each_alternate_ref(cache_one_alternate, &cache);
 102                 initialized = 1;
 103         }
 104
 105         for (i = 0; i < cache.nr; i++)
 106                 cb(cache.items[i]);
 107 }
 108
 109 static void rev_list_push(struct commit *commit, int mark)
 110 {
 111         if (!(commit->object.flags & mark)) {
 112                 commit->object.flags |= mark;
 113
 114                 if (parse_commit(commit))
 115                         return;
 116
 117                 prio_queue_put(&rev_list, commit);
 118
 119                 if (!(commit->object.flags & COMMON))
 120                         non_common_revs++;
 121         }
 122 }
 123
 124 static int rev_list_insert_ref(const char *refname, const struct object_id *oid)
 125 {
 126         struct object *o = deref_tag(parse_object(oid), refname, 0);
 127
 128         if (o && o->type == OBJ_COMMIT)
 129                 rev_list_push((struct commit *)o, SEEN);
 130
 131         return 0;
 132 }
 133
 134 static int rev_list_insert_ref_oid(const char *refname, const struct object_id *oid,
 135                                    int flag, void *cb_data)
 136 {
 137         return rev_list_insert_ref(refname, oid);
 138 }
 139
 140 static int clear_marks(const char *refname, const struct object_id *oid,
 141                        int flag, void *cb_data)
 142 {
 143         struct object *o = deref_tag(parse_object(oid), refname, 0);
 144
 145         if (o && o->type == OBJ_COMMIT)
 146                 clear_commit_marks((struct commit *)o,
 147                                    COMMON | COMMON_REF | SEEN | POPPED);
 148         return 0;
 149 }
 150
 151 /*
 152    This function marks a rev and its ancestors as common.
 153    In some cases, it is desirable to mark only the ancestors (for example
 154    when only the server does not yet know that they are common).
 155 */
 156
 157 static void mark_common(struct commit *commit,
 158                 int ancestors_only, int dont_parse)
 159 {
 160         if (commit != NULL && !(commit->object.flags & COMMON)) {
 161                 struct object *o = (struct object *)commit;
 162
 163                 if (!ancestors_only)
 164                         o->flags |= COMMON;
 165
 166                 if (!(o->flags & SEEN))
 167                         rev_list_push(commit, SEEN);
 168                 else {
 169                         struct commit_list *parents;
 170
 171                         if (!ancestors_only && !(o->flags & POPPED))
 172                                 non_common_revs--;
 173                         if (!o->parsed && !dont_parse)
 174                                 if (parse_commit(commit))
 175                                         return;
 176
 177                         for (parents = commit->parents;
 178                                         parents;
 179                                         parents = parents->next)
 180                                 mark_common(parents->item, 0, dont_parse);
 181                 }
 182         }
 183 }
 184
 185 /*
 186   Get the next rev to send, ignoring the common.
 187 */
 188
 189 static const struct object_id *get_rev(void)
 190 {
 191         struct commit *commit = NULL;
 192
 193         while (commit == NULL) {
 194                 unsigned int mark;
 195                 struct commit_list *parents;
 196
 197                 if (rev_list.nr == 0 || non_common_revs == 0)
 198                         return NULL;
 199
 200                 commit = prio_queue_get(&rev_list);
 201                 parse_commit(commit);
 202                 parents = commit->parents;
 203
 204                 commit->object.flags |= POPPED;
 205                 if (!(commit->object.flags & COMMON))
 206                         non_common_revs--;
 207
 208                 if (commit->object.flags & COMMON) {
 209                         /* do not send "have", and ignore ancestors */
 210                         commit = NULL;
 211                         mark = COMMON | SEEN;
 212                 } else if (commit->object.flags & COMMON_REF)
 213                         /* send "have", and ignore ancestors */
 214                         mark = COMMON | SEEN;
 215                 else
 216                         /* send "have", also for its ancestors */
 217                         mark = SEEN;
 218
 219                 while (parents) {
 220                         if (!(parents->item->object.flags & SEEN))
 221                                 rev_list_push(parents->item, mark);
 222                         if (mark & COMMON)
 223                                 mark_common(parents->item, 1, 0);
 224                         parents = parents->next;
 225                 }
 226         }
 227
 228         return &commit->object.oid;
 229 }
 230
 231 enum ack_type {
 232         NAK = 0,
 233         ACK,
 234         ACK_continue,
 235         ACK_common,
 236         ACK_ready
 237 };
 238
 239 static void consume_shallow_list(struct fetch_pack_args *args, int fd)
 240 {
 241         if (args->stateless_rpc && args->deepen) {
 242                 /* If we sent a depth we will get back "duplicate"
 243                  * shallow and unshallow commands every time there
 244                  * is a block of have lines exchanged.
 245                  */
 246                 char *line;
 247                 while ((line = packet_read_line(fd, NULL))) {
 248                         if (starts_with(line, "shallow "))
 249                                 continue;
 250                         if (starts_with(line, "unshallow "))
 251                                 continue;
 252                         die(_("git fetch-pack: expected shallow list"));
 253                 }
 254         }
 255 }
 256
 257 static enum ack_type get_ack(int fd, struct object_id *result_oid)
 258 {
 259         int len;
 260         char *line = packet_read_line(fd, &len);
 261         const char *arg;
 262
 263         if (!len)
 264                 die(_("git fetch-pack: expected ACK/NAK, got EOF"));
 265         if (!strcmp(line, "NAK"))
 266                 return NAK;
 267         if (skip_prefix(line, "ACK ", &arg)) {
 268                 if (!get_oid_hex(arg, result_oid)) {
 269                         arg += 40;
 270                         len -= arg - line;
 271                         if (len < 1)
 272                                 return ACK;
 273                         if (strstr(arg, "continue"))
 274                                 return ACK_continue;
 275                         if (strstr(arg, "common"))
 276                                 return ACK_common;
 277                         if (strstr(arg, "ready"))
 278                                 return ACK_ready;
 279                         return ACK;
 280                 }
 281         }
 282         if (skip_prefix(line, "ERR ", &arg))
 283                 die(_("remote error: %s"), arg);
 284         die(_("git fetch-pack: expected ACK/NAK, got '%s'"), line);
 285 }
 286
 287 static void send_request(struct fetch_pack_args *args,
 288                          int fd, struct strbuf *buf)
 289 {
 290         if (args->stateless_rpc) {
 291                 send_sideband(fd, -1, buf->buf, buf->len, LARGE_PACKET_MAX);
 292                 packet_flush(fd);
 293         } else
 294                 write_or_die(fd, buf->buf, buf->len);
 295 }
 296
 297 static void insert_one_alternate_object(struct object *obj)
 298 {
 299         rev_list_insert_ref(NULL, &obj->oid);
 300 }
 301
 302 #define INITIAL_FLUSH 16
 303 #define PIPESAFE_FLUSH 32
 304 #define LARGE_FLUSH 16384
 305
 306 static int next_flush(struct fetch_pack_args *args, int count)
 307 {
 308         if (args->stateless_rpc) {
 309                 if (count < LARGE_FLUSH)
 310                         count <<= 1;
 311                 else
 312                         count = count * 11 / 10;
 313         } else {
 314                 if (count < PIPESAFE_FLUSH)
 315                         count <<= 1;
 316                 else
 317                         count += PIPESAFE_FLUSH;
 318         }
 319         return count;
 320 }
 321
 322 static int find_common(struct fetch_pack_args *args,
 323                        int fd[2], struct object_id *result_oid,
 324                        struct ref *refs)
 325 {
 326         int fetching;
 327         int count = 0, flushes = 0, flush_at = INITIAL_FLUSH, retval;
 328         const struct object_id *oid;
 329         unsigned in_vain = 0;
 330         int got_continue = 0;
 331         int got_ready = 0;
 332         struct strbuf req_buf = STRBUF_INIT;
 333         size_t state_len = 0;
 334
 335         if (args->stateless_rpc && multi_ack == 1)
 336                 die(_("--stateless-rpc requires multi_ack_detailed"));
 337         if (marked)
 338                 for_each_ref(clear_marks, NULL);
 339         marked = 1;
 340
 341         for_each_ref(rev_list_insert_ref_oid, NULL);
 342         for_each_cached_alternate(insert_one_alternate_object);
 343
 344         fetching = 0;
 345         for ( ; refs ; refs = refs->next) {
 346                 struct object_id *remote = &refs->old_oid;
 347                 const char *remote_hex;
 348                 struct object *o;
 349
 350                 /*
 351                  * If that object is complete (i.e. it is an ancestor of a
 352                  * local ref), we tell them we have it but do not have to
 353                  * tell them about its ancestors, which they already know
 354                  * about.
 355                  *
 356                  * We use lookup_object here because we are only
 357                  * interested in the case we *know* the object is
 358                  * reachable and we have already scanned it.
 359                  */
 360                 if (((o = lookup_object(remote->hash)) != NULL) &&
 361                                 (o->flags & COMPLETE)) {
 362                         continue;
 363                 }
 364
 365                 remote_hex = oid_to_hex(remote);
 366                 if (!fetching) {
 367                         struct strbuf c = STRBUF_INIT;
 368                         if (multi_ack == 2)     strbuf_addstr(&c, " multi_ack_detailed");
 369                         if (multi_ack == 1)     strbuf_addstr(&c, " multi_ack");
 370                         if (no_done)            strbuf_addstr(&c, " no-done");
 371                         if (use_sideband == 2)  strbuf_addstr(&c, " side-band-64k");
 372                         if (use_sideband == 1)  strbuf_addstr(&c, " side-band");
 373                         if (args->deepen_relative) strbuf_addstr(&c, " deepen-relative");
 374                         if (args->use_thin_pack) strbuf_addstr(&c, " thin-pack");
 375                         if (args->no_progress)   strbuf_addstr(&c, " no-progress");
 376                         if (args->include_tag)   strbuf_addstr(&c, " include-tag");
 377                         if (prefer_ofs_delta)   strbuf_addstr(&c, " ofs-delta");
 378                         if (deepen_since_ok)    strbuf_addstr(&c, " deepen-since");
 379                         if (deepen_not_ok)      strbuf_addstr(&c, " deepen-not");
 380                         if (agent_supported)    strbuf_addf(&c, " agent=%s",
 381                                                             git_user_agent_sanitized());
 382                         packet_buf_write(&req_buf, "want %s%s\n", remote_hex, c.buf);
 383                         strbuf_release(&c);
 384                 } else
 385                         packet_buf_write(&req_buf, "want %s\n", remote_hex);
 386                 fetching++;
 387         }
 388
 389         if (!fetching) {
 390                 strbuf_release(&req_buf);
 391                 packet_flush(fd[1]);
 392                 return 1;
 393         }
 394
 395         if (is_repository_shallow())
 396                 write_shallow_commits(&req_buf, 1, NULL);
 397         if (args->depth > 0)
 398                 packet_buf_write(&req_buf, "deepen %d", args->depth);
 399         if (args->deepen_since) {
 400                 timestamp_t max_age = approxidate(args->deepen_since);
 401                 packet_buf_write(&req_buf, "deepen-since %"PRItime, max_age);
 402         }
 403         if (args->deepen_not) {
 404                 int i;
 405                 for (i = 0; i < args->deepen_not->nr; i++) {
 406                         struct string_list_item *s = args->deepen_not->items + i;
 407                         packet_buf_write(&req_buf, "deepen-not %s", s->string);
 408                 }
 409         }
 410         packet_buf_flush(&req_buf);
 411         state_len = req_buf.len;
 412
 413         if (args->deepen) {
 414                 char *line;
 415                 const char *arg;
 416                 struct object_id oid;
 417
 418                 send_request(args, fd[1], &req_buf);
 419                 while ((line = packet_read_line(fd[0], NULL))) {
 420                         if (skip_prefix(line, "shallow ", &arg)) {
 421                                 if (get_oid_hex(arg, &oid))
 422                                         die(_("invalid shallow line: %s"), line);
 423                                 register_shallow(&oid);
 424                                 continue;
 425                         }
 426                         if (skip_prefix(line, "unshallow ", &arg)) {
 427                                 if (get_oid_hex(arg, &oid))
 428                                         die(_("invalid unshallow line: %s"), line);
 429                                 if (!lookup_object(oid.hash))
 430                                         die(_("object not found: %s"), line);
 431                                 /* make sure that it is parsed as shallow */
 432                                 if (!parse_object(&oid))
 433                                         die(_("error in object: %s"), line);
 434                                 if (unregister_shallow(&oid))
 435                                         die(_("no shallow found: %s"), line);
 436                                 continue;
 437                         }
 438                         die(_("expected shallow/unshallow, got %s"), line);
 439                 }
 440         } else if (!args->stateless_rpc)
 441                 send_request(args, fd[1], &req_buf);
 442
 443         if (!args->stateless_rpc) {
 444                 /* If we aren't using the stateless-rpc interface
 445                  * we don't need to retain the headers.
 446                  */
 447                 strbuf_setlen(&req_buf, 0);
 448                 state_len = 0;
 449         }
 450
 451         flushes = 0;
 452         retval = -1;
 453         while ((oid = get_rev())) {
 454                 packet_buf_write(&req_buf, "have %s\n", oid_to_hex(oid));
 455                 print_verbose(args, "have %s", oid_to_hex(oid));
 456                 in_vain++;
 457                 if (flush_at <= ++count) {
 458                         int ack;
 459
 460                         packet_buf_flush(&req_buf);
 461                         send_request(args, fd[1], &req_buf);
 462                         strbuf_setlen(&req_buf, state_len);
 463                         flushes++;
 464                         flush_at = next_flush(args, count);
 465
 466                         /*
 467                          * We keep one window "ahead" of the other side, and
 468                          * will wait for an ACK only on the next one
 469                          */
 470                         if (!args->stateless_rpc && count == INITIAL_FLUSH)
 471                                 continue;
 472
 473                         consume_shallow_list(args, fd[0]);
 474                         do {
 475                                 ack = get_ack(fd[0], result_oid);
 476                                 if (ack)
 477                                         print_verbose(args, _("got %s %d %s"), "ack",
 478                                                       ack, oid_to_hex(result_oid));
 479                                 switch (ack) {
 480                                 case ACK:
 481                                         flushes = 0;
 482                                         multi_ack = 0;
 483                                         retval = 0;
 484                                         goto done;
 485                                 case ACK_common:
 486                                 case ACK_ready:
 487                                 case ACK_continue: {
 488                                         struct commit *commit =
 489                                                 lookup_commit(result_oid);
 490                                         if (!commit)
 491                                                 die(_("invalid commit %s"), oid_to_hex(result_oid));
 492                                         if (args->stateless_rpc
 493                                          && ack == ACK_common
 494                                          && !(commit->object.flags & COMMON)) {
 495                                                 /* We need to replay the have for this object
 496                                                  * on the next RPC request so the peer knows
 497                                                  * it is in common with us.
 498                                                  */
 499                                                 const char *hex = oid_to_hex(result_oid);
 500                                                 packet_buf_write(&req_buf, "have %s\n", hex);
 501                                                 state_len = req_buf.len;
 502                                                 /*
 503                                                  * Reset in_vain because an ack
 504                                                  * for this commit has not been
 505                                                  * seen.
 506                                                  */
 507                                                 in_vain = 0;
 508                                         } else if (!args->stateless_rpc
 509                                                    || ack != ACK_common)
 510                                                 in_vain = 0;
 511                                         mark_common(commit, 0, 1);
 512                                         retval = 0;
 513                                         got_continue = 1;
 514                                         if (ack == ACK_ready) {
 515                                                 clear_prio_queue(&rev_list);
 516                                                 got_ready = 1;
 517                                         }
 518                                         break;
 519                                         }
 520                                 }
 521                         } while (ack);
 522                         flushes--;
 523                         if (got_continue && MAX_IN_VAIN < in_vain) {
 524                                 print_verbose(args, _("giving up"));
 525                                 break; /* give up */
 526                         }
 527                 }
 528         }
 529 done:
 530         if (!got_ready || !no_done) {
 531                 packet_buf_write(&req_buf, "done\n");
 532                 send_request(args, fd[1], &req_buf);
 533         }
 534         print_verbose(args, _("done"));
 535         if (retval != 0) {
 536                 multi_ack = 0;
 537                 flushes++;
 538         }
 539         strbuf_release(&req_buf);
 540
 541         if (!got_ready || !no_done)
 542                 consume_shallow_list(args, fd[0]);
 543         while (flushes || multi_ack) {
 544                 int ack = get_ack(fd[0], result_oid);
 545                 if (ack) {
 546                         print_verbose(args, _("got %s (%d) %s"), "ack",
 547                                       ack, oid_to_hex(result_oid));
 548                         if (ack == ACK)
 549                                 return 0;
 550                         multi_ack = 1;
 551                         continue;
 552                 }
 553                 flushes--;
 554         }
 555         /* it is no error to fetch into a completely empty repo */
 556         return count ? retval : 0;
 557 }
 558
 559 static struct commit_list *complete;
 560
 561 static int mark_complete(const struct object_id *oid)
 562 {
 563         struct object *o = parse_object(oid);
 564
 565         while (o && o->type == OBJ_TAG) {
 566                 struct tag *t = (struct tag *) o;
 567                 if (!t->tagged)
 568                         break; /* broken repository */
 569                 o->flags |= COMPLETE;
 570                 o = parse_object(&t->tagged->oid);
 571         }
 572         if (o && o->type == OBJ_COMMIT) {
 573                 struct commit *commit = (struct commit *)o;
 574                 if (!(commit->object.flags & COMPLETE)) {
 575                         commit->object.flags |= COMPLETE;
 576                         commit_list_insert(commit, &complete);
 577                 }
 578         }
 579         return 0;
 580 }
 581
 582 static int mark_complete_oid(const char *refname, const struct object_id *oid,
 583                              int flag, void *cb_data)
 584 {
 585         return mark_complete(oid);
 586 }
 587
 588 static void mark_recent_complete_commits(struct fetch_pack_args *args,
 589                                          timestamp_t cutoff)
 590 {
 591         while (complete && cutoff <= complete->item->date) {
 592                 print_verbose(args, _("Marking %s as complete"),
 593                               oid_to_hex(&complete->item->object.oid));
 594                 pop_most_recent_commit(&complete, COMPLETE);
 595         }
 596 }
 597
 598 static void add_refs_to_oidset(struct oidset *oids, struct ref *refs)
 599 {
 600         for (; refs; refs = refs->next)
 601                 oidset_insert(oids, &refs->old_oid);
 602 }
 603
 604 static int tip_oids_contain(struct oidset *tip_oids,
 605                             struct ref *unmatched, struct ref *newlist,
 606                             const struct object_id *id)
 607 {
 608         /*
 609          * Note that this only looks at the ref lists the first time it's
 610          * called. This works out in filter_refs() because even though it may
 611          * add to "newlist" between calls, the additions will always be for
 612          * oids that are already in the set.
 613          */
 614         if (!tip_oids->map.tablesize) {
 615                 add_refs_to_oidset(tip_oids, unmatched);
 616                 add_refs_to_oidset(tip_oids, newlist);
 617         }
 618         return oidset_contains(tip_oids, id);
 619 }
 620
 621 static void filter_refs(struct fetch_pack_args *args,
 622                         struct ref **refs,
 623                         struct ref **sought, int nr_sought)
 624 {
 625         struct ref *newlist = NULL;
 626         struct ref **newtail = &newlist;
 627         struct ref *unmatched = NULL;
 628         struct ref *ref, *next;
 629         struct oidset tip_oids = OIDSET_INIT;
 630         int i;
 631
 632         i = 0;
 633         for (ref = *refs; ref; ref = next) {
 634                 int keep = 0;
 635                 next = ref->next;
 636
 637                 if (starts_with(ref->name, "refs/") &&
 638                     check_refname_format(ref->name, 0))
 639                         ; /* trash */
 640                 else {
 641                         while (i < nr_sought) {
 642                                 int cmp = strcmp(ref->name, sought[i]->name);
 643                                 if (cmp < 0)
 644                                         break; /* definitely do not have it */
 645                                 else if (cmp == 0) {
 646                                         keep = 1; /* definitely have it */
 647                                         sought[i]->match_status = REF_MATCHED;
 648                                 }
 649                                 i++;
 650                         }
 651                 }
 652
 653                 if (!keep && args->fetch_all &&
 654                     (!args->deepen || !starts_with(ref->name, "refs/tags/")))
 655                         keep = 1;
 656
 657                 if (keep) {
 658                         *newtail = ref;
 659                         ref->next = NULL;
 660                         newtail = &ref->next;
 661                 } else {
 662                         ref->next = unmatched;
 663                         unmatched = ref;
 664                 }
 665         }
 666
 667         /* Append unmatched requests to the list */
 668         for (i = 0; i < nr_sought; i++) {
 669                 struct object_id oid;
 670                 const char *p;
 671
 672                 ref = sought[i];
 673                 if (ref->match_status != REF_NOT_MATCHED)
 674                         continue;
 675                 if (parse_oid_hex(ref->name, &oid, &p) ||
 676                     *p != '\0' ||
 677                     oidcmp(&oid, &ref->old_oid))
 678                         continue;
 679
 680                 if ((allow_unadvertised_object_request &
 681                      (ALLOW_TIP_SHA1 | ALLOW_REACHABLE_SHA1)) ||
 682                     tip_oids_contain(&tip_oids, unmatched, newlist,
 683                                      &ref->old_oid)) {
 684                         ref->match_status = REF_MATCHED;
 685                         *newtail = copy_ref(ref);
 686                         newtail = &(*newtail)->next;
 687                 } else {
 688                         ref->match_status = REF_UNADVERTISED_NOT_ALLOWED;
 689                 }
 690         }
 691
 692         oidset_clear(&tip_oids);
 693         for (ref = unmatched; ref; ref = next) {
 694                 next = ref->next;
 695                 free(ref);
 696         }
 697
 698         *refs = newlist;
 699 }
 700
 701 static void mark_alternate_complete(struct object *obj)
 702 {
 703         mark_complete(&obj->oid);
 704 }
 705
 706 static int everything_local(struct fetch_pack_args *args,
 707                             struct ref **refs,
 708                             struct ref **sought, int nr_sought)
 709 {
 710         struct ref *ref;
 711         int retval;
 712         timestamp_t cutoff = 0;
 713
 714         save_commit_buffer = 0;
 715
 716         for (ref = *refs; ref; ref = ref->next) {
 717                 struct object *o;
 718
 719                 if (!has_object_file(&ref->old_oid))
 720                         continue;
 721
 722                 o = parse_object(&ref->old_oid);
 723                 if (!o)
 724                         continue;
 725
 726                 /* We already have it -- which may mean that we were
 727                  * in sync with the other side at some time after
 728                  * that (it is OK if we guess wrong here).
 729                  */
 730                 if (o->type == OBJ_COMMIT) {
 731                         struct commit *commit = (struct commit *)o;
 732                         if (!cutoff || cutoff < commit->date)
 733                                 cutoff = commit->date;
 734                 }
 735         }
 736
 737         if (!args->deepen) {
 738                 for_each_ref(mark_complete_oid, NULL);
 739                 for_each_cached_alternate(mark_alternate_complete);
 740                 commit_list_sort_by_date(&complete);
 741                 if (cutoff)
 742                         mark_recent_complete_commits(args, cutoff);
 743         }
 744
 745         /*
 746          * Mark all complete remote refs as common refs.
 747          * Don't mark them common yet; the server has to be told so first.
 748          */
 749         for (ref = *refs; ref; ref = ref->next) {
 750                 struct object *o = deref_tag(lookup_object(ref->old_oid.hash),
 751                                              NULL, 0);
 752
 753                 if (!o || o->type != OBJ_COMMIT || !(o->flags & COMPLETE))
 754                         continue;
 755
 756                 if (!(o->flags & SEEN)) {
 757                         rev_list_push((struct commit *)o, COMMON_REF | SEEN);
 758
 759                         mark_common((struct commit *)o, 1, 1);
 760                 }
 761         }
 762
 763         filter_refs(args, refs, sought, nr_sought);
 764
 765         for (retval = 1, ref = *refs; ref ; ref = ref->next) {
 766                 const struct object_id *remote = &ref->old_oid;
 767                 struct object *o;
 768
 769                 o = lookup_object(remote->hash);
 770                 if (!o || !(o->flags & COMPLETE)) {
 771                         retval = 0;
 772                         print_verbose(args, "want %s (%s)", oid_to_hex(remote),
 773                                       ref->name);
 774                         continue;
 775                 }
 776                 print_verbose(args, _("already have %s (%s)"), oid_to_hex(remote),
 777                               ref->name);
 778         }
 779         return retval;
 780 }
 781
 782 static int sideband_demux(int in, int out, void *data)
 783 {
 784         int *xd = data;
 785         int ret;
 786
 787         ret = recv_sideband("fetch-pack", xd[0], out);
 788         close(out);
 789         return ret;
 790 }
 791
 792 static int get_pack(struct fetch_pack_args *args,
 793                     int xd[2], char **pack_lockfile)
 794 {
 795         struct async demux;
 796         int do_keep = args->keep_pack;
 797         const char *cmd_name;
 798         struct pack_header header;
 799         int pass_header = 0;
 800         struct child_process cmd = CHILD_PROCESS_INIT;
 801         int ret;
 802
 803         memset(&demux, 0, sizeof(demux));
 804         if (use_sideband) {
 805                 /* xd[] is talking with upload-pack; subprocess reads from
 806                  * xd[0], spits out band#2 to stderr, and feeds us band#1
 807                  * through demux->out.
 808                  */
 809                 demux.proc = sideband_demux;
 810                 demux.data = xd;
 811                 demux.out = -1;
 812                 demux.isolate_sigpipe = 1;
 813                 if (start_async(&demux))
 814                         die(_("fetch-pack: unable to fork off sideband demultiplexer"));
 815         }
 816         else
 817                 demux.out = xd[0];
 818
 819         if (!args->keep_pack && unpack_limit) {
 820
 821                 if (read_pack_header(demux.out, &header))
 822                         die(_("protocol error: bad pack header"));
 823                 pass_header = 1;
 824                 if (ntohl(header.hdr_entries) < unpack_limit)
 825                         do_keep = 0;
 826                 else
 827                         do_keep = 1;
 828         }
 829
 830         if (alternate_shallow_file) {
 831                 argv_array_push(&cmd.args, "--shallow-file");
 832                 argv_array_push(&cmd.args, alternate_shallow_file);
 833         }
 834
 835         if (do_keep) {
 836                 if (pack_lockfile)
 837                         cmd.out = -1;
 838                 cmd_name = "index-pack";
 839                 argv_array_push(&cmd.args, cmd_name);
 840                 argv_array_push(&cmd.args, "--stdin");
 841                 if (!args->quiet && !args->no_progress)
 842                         argv_array_push(&cmd.args, "-v");
 843                 if (args->use_thin_pack)
 844                         argv_array_push(&cmd.args, "--fix-thin");
 845                 if (args->lock_pack || unpack_limit) {
 846                         char hostname[HOST_NAME_MAX + 1];
 847                         if (xgethostname(hostname, sizeof(hostname)))
 848                                 xsnprintf(hostname, sizeof(hostname), "localhost");
 849                         argv_array_pushf(&cmd.args,
 850                                         "--keep=fetch-pack %"PRIuMAX " on %s",
 851                                         (uintmax_t)getpid(), hostname);
 852                 }
 853                 if (args->check_self_contained_and_connected)
 854                         argv_array_push(&cmd.args, "--check-self-contained-and-connected");
 855         }
 856         else {
 857                 cmd_name = "unpack-objects";
 858                 argv_array_push(&cmd.args, cmd_name);
 859                 if (args->quiet || args->no_progress)
 860                         argv_array_push(&cmd.args, "-q");
 861                 args->check_self_contained_and_connected = 0;
 862         }
 863
 864         if (pass_header)
 865                 argv_array_pushf(&cmd.args, "--pack_header=%"PRIu32",%"PRIu32,
 866                                  ntohl(header.hdr_version),
 867                                  ntohl(header.hdr_entries));
 868         if (fetch_fsck_objects >= 0
 869             ? fetch_fsck_objects
 870             : transfer_fsck_objects >= 0
 871             ? transfer_fsck_objects
 872             : 0)
 873                 argv_array_push(&cmd.args, "--strict");
 874
 875         cmd.in = demux.out;
 876         cmd.git_cmd = 1;
 877         if (start_command(&cmd))
 878                 die(_("fetch-pack: unable to fork off %s"), cmd_name);
 879         if (do_keep && pack_lockfile) {
 880                 *pack_lockfile = index_pack_lockfile(cmd.out);
 881                 close(cmd.out);
 882         }
 883
 884         if (!use_sideband)
 885                 /* Closed by start_command() */
 886                 xd[0] = -1;
 887
 888         ret = finish_command(&cmd);
 889         if (!ret || (args->check_self_contained_and_connected && ret == 1))
 890                 args->self_contained_and_connected =
 891                         args->check_self_contained_and_connected &&
 892                         ret == 0;
 893         else
 894                 die(_("%s failed"), cmd_name);
 895         if (use_sideband && finish_async(&demux))
 896                 die(_("error in sideband demultiplexer"));
 897         return 0;
 898 }
 899
 900 static int cmp_ref_by_name(const void *a_, const void *b_)
 901 {
 902         const struct ref *a = *((const struct ref **)a_);
 903         const struct ref *b = *((const struct ref **)b_);
 904         return strcmp(a->name, b->name);
 905 }
 906
 907 static struct ref *do_fetch_pack(struct fetch_pack_args *args,
 908                                  int fd[2],
 909                                  const struct ref *orig_ref,
 910                                  struct ref **sought, int nr_sought,
 911                                  struct shallow_info *si,
 912                                  char **pack_lockfile)
 913 {
 914         struct ref *ref = copy_ref_list(orig_ref);
 915         struct object_id oid;
 916         const char *agent_feature;
 917         int agent_len;
 918
 919         sort_ref_list(&ref, ref_compare_name);
 920         QSORT(sought, nr_sought, cmp_ref_by_name);
 921
 922         if ((args->depth > 0 || is_repository_shallow()) && !server_supports("shallow"))
 923                 die(_("Server does not support shallow clients"));
 924         if (args->depth > 0 || args->deepen_since || args->deepen_not)
 925                 args->deepen = 1;
 926         if (server_supports("multi_ack_detailed")) {
 927                 print_verbose(args, _("Server supports multi_ack_detailed"));
 928                 multi_ack = 2;
 929                 if (server_supports("no-done")) {
 930                         print_verbose(args, _("Server supports no-done"));
 931                         if (args->stateless_rpc)
 932                                 no_done = 1;
 933                 }
 934         }
 935         else if (server_supports("multi_ack")) {
 936                 print_verbose(args, _("Server supports multi_ack"));
 937                 multi_ack = 1;
 938         }
 939         if (server_supports("side-band-64k")) {
 940                 print_verbose(args, _("Server supports side-band-64k"));
 941                 use_sideband = 2;
 942         }
 943         else if (server_supports("side-band")) {
 944                 print_verbose(args, _("Server supports side-band"));
 945                 use_sideband = 1;
 946         }
 947         if (server_supports("allow-tip-sha1-in-want")) {
 948                 print_verbose(args, _("Server supports allow-tip-sha1-in-want"));
 949                 allow_unadvertised_object_request |= ALLOW_TIP_SHA1;
 950         }
 951         if (server_supports("allow-reachable-sha1-in-want")) {
 952                 print_verbose(args, _("Server supports allow-reachable-sha1-in-want"));
 953                 allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
 954         }
 955         if (!server_supports("thin-pack"))
 956                 args->use_thin_pack = 0;
 957         if (!server_supports("no-progress"))
 958                 args->no_progress = 0;
 959         if (!server_supports("include-tag"))
 960                 args->include_tag = 0;
 961         if (server_supports("ofs-delta"))
 962                 print_verbose(args, _("Server supports ofs-delta"));
 963         else
 964                 prefer_ofs_delta = 0;
 965
 966         if ((agent_feature = server_feature_value("agent", &agent_len))) {
 967                 agent_supported = 1;
 968                 if (agent_len)
 969                         print_verbose(args, _("Server version is %.*s"),
 970                                       agent_len, agent_feature);
 971         }
 972         if (server_supports("deepen-since"))
 973                 deepen_since_ok = 1;
 974         else if (args->deepen_since)
 975                 die(_("Server does not support --shallow-since"));
 976         if (server_supports("deepen-not"))
 977                 deepen_not_ok = 1;
 978         else if (args->deepen_not)
 979                 die(_("Server does not support --shallow-exclude"));
 980         if (!server_supports("deepen-relative") && args->deepen_relative)
 981                 die(_("Server does not support --deepen"));
 982
 983         if (everything_local(args, &ref, sought, nr_sought)) {
 984                 packet_flush(fd[1]);
 985                 goto all_done;
 986         }
 987         if (find_common(args, fd, &oid, ref) < 0)
 988                 if (!args->keep_pack)
 989                         /* When cloning, it is not unusual to have
 990                          * no common commit.
 991                          */
 992                         warning(_("no common commits"));
 993
 994         if (args->stateless_rpc)
 995                 packet_flush(fd[1]);
 996         if (args->deepen)
 997                 setup_alternate_shallow(&shallow_lock, &alternate_shallow_file,
 998                                         NULL);
 999         else if (si->nr_ours || si->nr_theirs)
1000                 alternate_shallow_file = setup_temporary_shallow(si->shallow);
1001         else
1002                 alternate_shallow_file = NULL;
1003         if (get_pack(args, fd, pack_lockfile))
1004                 die(_("git fetch-pack: fetch failed."));
1005
1006  all_done:
1007         return ref;
1008 }
1009
1010 static void fetch_pack_config(void)
1011 {
1012         git_config_get_int("fetch.unpacklimit", &fetch_unpack_limit);
1013         git_config_get_int("transfer.unpacklimit", &transfer_unpack_limit);
1014         git_config_get_bool("repack.usedeltabaseoffset", &prefer_ofs_delta);
1015         git_config_get_bool("fetch.fsckobjects", &fetch_fsck_objects);
1016         git_config_get_bool("transfer.fsckobjects", &transfer_fsck_objects);
1017
1018         git_config(git_default_config, NULL);
1019 }
1020
1021 static void fetch_pack_setup(void)
1022 {
1023         static int did_setup;
1024         if (did_setup)
1025                 return;
1026         fetch_pack_config();
1027         if (0 <= transfer_unpack_limit)
1028                 unpack_limit = transfer_unpack_limit;
1029         else if (0 <= fetch_unpack_limit)
1030                 unpack_limit = fetch_unpack_limit;
1031         did_setup = 1;
1032 }
1033
1034 static int remove_duplicates_in_refs(struct ref **ref, int nr)
1035 {
1036         struct string_list names = STRING_LIST_INIT_NODUP;
1037         int src, dst;
1038
1039         for (src = dst = 0; src < nr; src++) {
1040                 struct string_list_item *item;
1041                 item = string_list_insert(&names, ref[src]->name);
1042                 if (item->util)
1043                         continue; /* already have it */
1044                 item->util = ref[src];
1045                 if (src != dst)
1046                         ref[dst] = ref[src];
1047                 dst++;
1048         }
1049         for (src = dst; src < nr; src++)
1050                 ref[src] = NULL;
1051         string_list_clear(&names, 0);
1052         return dst;
1053 }
1054
1055 static void update_shallow(struct fetch_pack_args *args,
1056                            struct ref **sought, int nr_sought,
1057                            struct shallow_info *si)
1058 {
1059         struct oid_array ref = OID_ARRAY_INIT;
1060         int *status;
1061         int i;
1062
1063         if (args->deepen && alternate_shallow_file) {
1064                 if (*alternate_shallow_file == '\0') { /* --unshallow */
1065                         unlink_or_warn(git_path_shallow());
1066                         rollback_lock_file(&shallow_lock);
1067                 } else
1068                         commit_lock_file(&shallow_lock);
1069                 return;
1070         }
1071
1072         if (!si->shallow || !si->shallow->nr)
1073                 return;
1074
1075         if (args->cloning) {
1076                 /*
1077                  * remote is shallow, but this is a clone, there are
1078                  * no objects in repo to worry about. Accept any
1079                  * shallow points that exist in the pack (iow in repo
1080                  * after get_pack() and reprepare_packed_git())
1081                  */
1082                 struct oid_array extra = OID_ARRAY_INIT;
1083                 struct object_id *oid = si->shallow->oid;
1084                 for (i = 0; i < si->shallow->nr; i++)
1085                         if (has_object_file(&oid[i]))
1086                                 oid_array_append(&extra, &oid[i]);
1087                 if (extra.nr) {
1088                         setup_alternate_shallow(&shallow_lock,
1089                                                 &alternate_shallow_file,
1090                                                 &extra);
1091                         commit_lock_file(&shallow_lock);
1092                 }
1093                 oid_array_clear(&extra);
1094                 return;
1095         }
1096
1097         if (!si->nr_ours && !si->nr_theirs)
1098                 return;
1099
1100         remove_nonexistent_theirs_shallow(si);
1101         if (!si->nr_ours && !si->nr_theirs)
1102                 return;
1103         for (i = 0; i < nr_sought; i++)
1104                 oid_array_append(&ref, &sought[i]->old_oid);
1105         si->ref = &ref;
1106
1107         if (args->update_shallow) {
1108                 /*
1109                  * remote is also shallow, .git/shallow may be updated
1110                  * so all refs can be accepted. Make sure we only add
1111                  * shallow roots that are actually reachable from new
1112                  * refs.
1113                  */
1114                 struct oid_array extra = OID_ARRAY_INIT;
1115                 struct object_id *oid = si->shallow->oid;
1116                 assign_shallow_commits_to_refs(si, NULL, NULL);
1117                 if (!si->nr_ours && !si->nr_theirs) {
1118                         oid_array_clear(&ref);
1119                         return;
1120                 }
1121                 for (i = 0; i < si->nr_ours; i++)
1122                         oid_array_append(&extra, &oid[si->ours[i]]);
1123                 for (i = 0; i < si->nr_theirs; i++)
1124                         oid_array_append(&extra, &oid[si->theirs[i]]);
1125                 setup_alternate_shallow(&shallow_lock,
1126                                         &alternate_shallow_file,
1127                                         &extra);
1128                 commit_lock_file(&shallow_lock);
1129                 oid_array_clear(&extra);
1130                 oid_array_clear(&ref);
1131                 return;
1132         }
1133
1134         /*
1135          * remote is also shallow, check what ref is safe to update
1136          * without updating .git/shallow
1137          */
1138         status = xcalloc(nr_sought, sizeof(*status));
1139         assign_shallow_commits_to_refs(si, NULL, status);
1140         if (si->nr_ours || si->nr_theirs) {
1141                 for (i = 0; i < nr_sought; i++)
1142                         if (status[i])
1143                                 sought[i]->status = REF_STATUS_REJECT_SHALLOW;
1144         }
1145         free(status);
1146         oid_array_clear(&ref);
1147 }
1148
1149 struct ref *fetch_pack(struct fetch_pack_args *args,
1150                        int fd[], struct child_process *conn,
1151                        const struct ref *ref,
1152                        const char *dest,
1153                        struct ref **sought, int nr_sought,
1154                        struct oid_array *shallow,
1155                        char **pack_lockfile)
1156 {
1157         struct ref *ref_cpy;
1158         struct shallow_info si;
1159
1160         fetch_pack_setup();
1161         if (nr_sought)
1162                 nr_sought = remove_duplicates_in_refs(sought, nr_sought);
1163
1164         if (!ref) {
1165                 packet_flush(fd[1]);
1166                 die(_("no matching remote head"));
1167         }
1168         prepare_shallow_info(&si, shallow);
1169         ref_cpy = do_fetch_pack(args, fd, ref, sought, nr_sought,
1170                                 &si, pack_lockfile);
1171         reprepare_packed_git();
1172         update_shallow(args, sought, nr_sought, &si);
1173         clear_shallow_info(&si);
1174         return ref_cpy;
1175 }
1176
1177 int report_unmatched_refs(struct ref **sought, int nr_sought)
1178 {
1179         int i, ret = 0;
1180
1181         for (i = 0; i < nr_sought; i++) {
1182                 if (!sought[i])
1183                         continue;
1184                 switch (sought[i]->match_status) {
1185                 case REF_MATCHED:
1186                         continue;
1187                 case REF_NOT_MATCHED:
1188                         error(_("no such remote ref %s"), sought[i]->name);
1189                         break;
1190                 case REF_UNADVERTISED_NOT_ALLOWED:
1191                         error(_("Server does not allow request for unadvertised object %s"),
1192                               sought[i]->name);
1193                         break;
1194                 }
1195                 ret = 1;
1196         }
1197         return ret;
1198 }