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         if (args->no_dependents)
 454                 goto done;
 455         while ((oid = get_rev())) {
 456                 packet_buf_write(&req_buf, "have %s\n", oid_to_hex(oid));
 457                 print_verbose(args, "have %s", oid_to_hex(oid));
 458                 in_vain++;
 459                 if (flush_at <= ++count) {
 460                         int ack;
 461
 462                         packet_buf_flush(&req_buf);
 463                         send_request(args, fd[1], &req_buf);
 464                         strbuf_setlen(&req_buf, state_len);
 465                         flushes++;
 466                         flush_at = next_flush(args, count);
 467
 468                         /*
 469                          * We keep one window "ahead" of the other side, and
 470                          * will wait for an ACK only on the next one
 471                          */
 472                         if (!args->stateless_rpc && count == INITIAL_FLUSH)
 473                                 continue;
 474
 475                         consume_shallow_list(args, fd[0]);
 476                         do {
 477                                 ack = get_ack(fd[0], result_oid);
 478                                 if (ack)
 479                                         print_verbose(args, _("got %s %d %s"), "ack",
 480                                                       ack, oid_to_hex(result_oid));
 481                                 switch (ack) {
 482                                 case ACK:
 483                                         flushes = 0;
 484                                         multi_ack = 0;
 485                                         retval = 0;
 486                                         goto done;
 487                                 case ACK_common:
 488                                 case ACK_ready:
 489                                 case ACK_continue: {
 490                                         struct commit *commit =
 491                                                 lookup_commit(result_oid);
 492                                         if (!commit)
 493                                                 die(_("invalid commit %s"), oid_to_hex(result_oid));
 494                                         if (args->stateless_rpc
 495                                          && ack == ACK_common
 496                                          && !(commit->object.flags & COMMON)) {
 497                                                 /* We need to replay the have for this object
 498                                                  * on the next RPC request so the peer knows
 499                                                  * it is in common with us.
 500                                                  */
 501                                                 const char *hex = oid_to_hex(result_oid);
 502                                                 packet_buf_write(&req_buf, "have %s\n", hex);
 503                                                 state_len = req_buf.len;
 504                                                 /*
 505                                                  * Reset in_vain because an ack
 506                                                  * for this commit has not been
 507                                                  * seen.
 508                                                  */
 509                                                 in_vain = 0;
 510                                         } else if (!args->stateless_rpc
 511                                                    || ack != ACK_common)
 512                                                 in_vain = 0;
 513                                         mark_common(commit, 0, 1);
 514                                         retval = 0;
 515                                         got_continue = 1;
 516                                         if (ack == ACK_ready) {
 517                                                 clear_prio_queue(&rev_list);
 518                                                 got_ready = 1;
 519                                         }
 520                                         break;
 521                                         }
 522                                 }
 523                         } while (ack);
 524                         flushes--;
 525                         if (got_continue && MAX_IN_VAIN < in_vain) {
 526                                 print_verbose(args, _("giving up"));
 527                                 break; /* give up */
 528                         }
 529                 }
 530         }
 531 done:
 532         if (!got_ready || !no_done) {
 533                 packet_buf_write(&req_buf, "done\n");
 534                 send_request(args, fd[1], &req_buf);
 535         }
 536         print_verbose(args, _("done"));
 537         if (retval != 0) {
 538                 multi_ack = 0;
 539                 flushes++;
 540         }
 541         strbuf_release(&req_buf);
 542
 543         if (!got_ready || !no_done)
 544                 consume_shallow_list(args, fd[0]);
 545         while (flushes || multi_ack) {
 546                 int ack = get_ack(fd[0], result_oid);
 547                 if (ack) {
 548                         print_verbose(args, _("got %s (%d) %s"), "ack",
 549                                       ack, oid_to_hex(result_oid));
 550                         if (ack == ACK)
 551                                 return 0;
 552                         multi_ack = 1;
 553                         continue;
 554                 }
 555                 flushes--;
 556         }
 557         /* it is no error to fetch into a completely empty repo */
 558         return count ? retval : 0;
 559 }
 560
 561 static struct commit_list *complete;
 562
 563 static int mark_complete(const struct object_id *oid)
 564 {
 565         struct object *o = parse_object(oid);
 566
 567         while (o && o->type == OBJ_TAG) {
 568                 struct tag *t = (struct tag *) o;
 569                 if (!t->tagged)
 570                         break; /* broken repository */
 571                 o->flags |= COMPLETE;
 572                 o = parse_object(&t->tagged->oid);
 573         }
 574         if (o && o->type == OBJ_COMMIT) {
 575                 struct commit *commit = (struct commit *)o;
 576                 if (!(commit->object.flags & COMPLETE)) {
 577                         commit->object.flags |= COMPLETE;
 578                         commit_list_insert(commit, &complete);
 579                 }
 580         }
 581         return 0;
 582 }
 583
 584 static int mark_complete_oid(const char *refname, const struct object_id *oid,
 585                              int flag, void *cb_data)
 586 {
 587         return mark_complete(oid);
 588 }
 589
 590 static void mark_recent_complete_commits(struct fetch_pack_args *args,
 591                                          timestamp_t cutoff)
 592 {
 593         while (complete && cutoff <= complete->item->date) {
 594                 print_verbose(args, _("Marking %s as complete"),
 595                               oid_to_hex(&complete->item->object.oid));
 596                 pop_most_recent_commit(&complete, COMPLETE);
 597         }
 598 }
 599
 600 static void add_refs_to_oidset(struct oidset *oids, struct ref *refs)
 601 {
 602         for (; refs; refs = refs->next)
 603                 oidset_insert(oids, &refs->old_oid);
 604 }
 605
 606 static int tip_oids_contain(struct oidset *tip_oids,
 607                             struct ref *unmatched, struct ref *newlist,
 608                             const struct object_id *id)
 609 {
 610         /*
 611          * Note that this only looks at the ref lists the first time it's
 612          * called. This works out in filter_refs() because even though it may
 613          * add to "newlist" between calls, the additions will always be for
 614          * oids that are already in the set.
 615          */
 616         if (!tip_oids->map.map.tablesize) {
 617                 add_refs_to_oidset(tip_oids, unmatched);
 618                 add_refs_to_oidset(tip_oids, newlist);
 619         }
 620         return oidset_contains(tip_oids, id);
 621 }
 622
 623 static void filter_refs(struct fetch_pack_args *args,
 624                         struct ref **refs,
 625                         struct ref **sought, int nr_sought)
 626 {
 627         struct ref *newlist = NULL;
 628         struct ref **newtail = &newlist;
 629         struct ref *unmatched = NULL;
 630         struct ref *ref, *next;
 631         struct oidset tip_oids = OIDSET_INIT;
 632         int i;
 633
 634         i = 0;
 635         for (ref = *refs; ref; ref = next) {
 636                 int keep = 0;
 637                 next = ref->next;
 638
 639                 if (starts_with(ref->name, "refs/") &&
 640                     check_refname_format(ref->name, 0))
 641                         ; /* trash */
 642                 else {
 643                         while (i < nr_sought) {
 644                                 int cmp = strcmp(ref->name, sought[i]->name);
 645                                 if (cmp < 0)
 646                                         break; /* definitely do not have it */
 647                                 else if (cmp == 0) {
 648                                         keep = 1; /* definitely have it */
 649                                         sought[i]->match_status = REF_MATCHED;
 650                                 }
 651                                 i++;
 652                         }
 653                 }
 654
 655                 if (!keep && args->fetch_all &&
 656                     (!args->deepen || !starts_with(ref->name, "refs/tags/")))
 657                         keep = 1;
 658
 659                 if (keep) {
 660                         *newtail = ref;
 661                         ref->next = NULL;
 662                         newtail = &ref->next;
 663                 } else {
 664                         ref->next = unmatched;
 665                         unmatched = ref;
 666                 }
 667         }
 668
 669         /* Append unmatched requests to the list */
 670         for (i = 0; i < nr_sought; i++) {
 671                 struct object_id oid;
 672                 const char *p;
 673
 674                 ref = sought[i];
 675                 if (ref->match_status != REF_NOT_MATCHED)
 676                         continue;
 677                 if (parse_oid_hex(ref->name, &oid, &p) ||
 678                     *p != '\0' ||
 679                     oidcmp(&oid, &ref->old_oid))
 680                         continue;
 681
 682                 if ((allow_unadvertised_object_request &
 683                      (ALLOW_TIP_SHA1 | ALLOW_REACHABLE_SHA1)) ||
 684                     tip_oids_contain(&tip_oids, unmatched, newlist,
 685                                      &ref->old_oid)) {
 686                         ref->match_status = REF_MATCHED;
 687                         *newtail = copy_ref(ref);
 688                         newtail = &(*newtail)->next;
 689                 } else {
 690                         ref->match_status = REF_UNADVERTISED_NOT_ALLOWED;
 691                 }
 692         }
 693
 694         oidset_clear(&tip_oids);
 695         for (ref = unmatched; ref; ref = next) {
 696                 next = ref->next;
 697                 free(ref);
 698         }
 699
 700         *refs = newlist;
 701 }
 702
 703 static void mark_alternate_complete(struct object *obj)
 704 {
 705         mark_complete(&obj->oid);
 706 }
 707
 708 static int everything_local(struct fetch_pack_args *args,
 709                             struct ref **refs,
 710                             struct ref **sought, int nr_sought)
 711 {
 712         struct ref *ref;
 713         int retval;
 714         timestamp_t cutoff = 0;
 715
 716         save_commit_buffer = 0;
 717
 718         for (ref = *refs; ref; ref = ref->next) {
 719                 struct object *o;
 720
 721                 if (!has_object_file(&ref->old_oid))
 722                         continue;
 723
 724                 o = parse_object(&ref->old_oid);
 725                 if (!o)
 726                         continue;
 727
 728                 /* We already have it -- which may mean that we were
 729                  * in sync with the other side at some time after
 730                  * that (it is OK if we guess wrong here).
 731                  */
 732                 if (o->type == OBJ_COMMIT) {
 733                         struct commit *commit = (struct commit *)o;
 734                         if (!cutoff || cutoff < commit->date)
 735                                 cutoff = commit->date;
 736                 }
 737         }
 738
 739         if (!args->no_dependents) {
 740                 if (!args->deepen) {
 741                         for_each_ref(mark_complete_oid, NULL);
 742                         for_each_cached_alternate(mark_alternate_complete);
 743                         commit_list_sort_by_date(&complete);
 744                         if (cutoff)
 745                                 mark_recent_complete_commits(args, cutoff);
 746                 }
 747
 748                 /*
 749                  * Mark all complete remote refs as common refs.
 750                  * Don't mark them common yet; the server has to be told so first.
 751                  */
 752                 for (ref = *refs; ref; ref = ref->next) {
 753                         struct object *o = deref_tag(lookup_object(ref->old_oid.hash),
 754                                                      NULL, 0);
 755
 756                         if (!o || o->type != OBJ_COMMIT || !(o->flags & COMPLETE))
 757                                 continue;
 758
 759                         if (!(o->flags & SEEN)) {
 760                                 rev_list_push((struct commit *)o, COMMON_REF | SEEN);
 761
 762                                 mark_common((struct commit *)o, 1, 1);
 763                         }
 764                 }
 765         }
 766
 767         filter_refs(args, refs, sought, nr_sought);
 768
 769         for (retval = 1, ref = *refs; ref ; ref = ref->next) {
 770                 const struct object_id *remote = &ref->old_oid;
 771                 struct object *o;
 772
 773                 o = lookup_object(remote->hash);
 774                 if (!o || !(o->flags & COMPLETE)) {
 775                         retval = 0;
 776                         print_verbose(args, "want %s (%s)", oid_to_hex(remote),
 777                                       ref->name);
 778                         continue;
 779                 }
 780                 print_verbose(args, _("already have %s (%s)"), oid_to_hex(remote),
 781                               ref->name);
 782         }
 783         return retval;
 784 }
 785
 786 static int sideband_demux(int in, int out, void *data)
 787 {
 788         int *xd = data;
 789         int ret;
 790
 791         ret = recv_sideband("fetch-pack", xd[0], out);
 792         close(out);
 793         return ret;
 794 }
 795
 796 static int get_pack(struct fetch_pack_args *args,
 797                     int xd[2], char **pack_lockfile)
 798 {
 799         struct async demux;
 800         int do_keep = args->keep_pack;
 801         const char *cmd_name;
 802         struct pack_header header;
 803         int pass_header = 0;
 804         struct child_process cmd = CHILD_PROCESS_INIT;
 805         int ret;
 806
 807         memset(&demux, 0, sizeof(demux));
 808         if (use_sideband) {
 809                 /* xd[] is talking with upload-pack; subprocess reads from
 810                  * xd[0], spits out band#2 to stderr, and feeds us band#1
 811                  * through demux->out.
 812                  */
 813                 demux.proc = sideband_demux;
 814                 demux.data = xd;
 815                 demux.out = -1;
 816                 demux.isolate_sigpipe = 1;
 817                 if (start_async(&demux))
 818                         die(_("fetch-pack: unable to fork off sideband demultiplexer"));
 819         }
 820         else
 821                 demux.out = xd[0];
 822
 823         if (!args->keep_pack && unpack_limit) {
 824
 825                 if (read_pack_header(demux.out, &header))
 826                         die(_("protocol error: bad pack header"));
 827                 pass_header = 1;
 828                 if (ntohl(header.hdr_entries) < unpack_limit)
 829                         do_keep = 0;
 830                 else
 831                         do_keep = 1;
 832         }
 833
 834         if (alternate_shallow_file) {
 835                 argv_array_push(&cmd.args, "--shallow-file");
 836                 argv_array_push(&cmd.args, alternate_shallow_file);
 837         }
 838
 839         if (do_keep || args->from_promisor) {
 840                 if (pack_lockfile)
 841                         cmd.out = -1;
 842                 cmd_name = "index-pack";
 843                 argv_array_push(&cmd.args, cmd_name);
 844                 argv_array_push(&cmd.args, "--stdin");
 845                 if (!args->quiet && !args->no_progress)
 846                         argv_array_push(&cmd.args, "-v");
 847                 if (args->use_thin_pack)
 848                         argv_array_push(&cmd.args, "--fix-thin");
 849                 if (do_keep && (args->lock_pack || unpack_limit)) {
 850                         char hostname[HOST_NAME_MAX + 1];
 851                         if (xgethostname(hostname, sizeof(hostname)))
 852                                 xsnprintf(hostname, sizeof(hostname), "localhost");
 853                         argv_array_pushf(&cmd.args,
 854                                         "--keep=fetch-pack %"PRIuMAX " on %s",
 855                                         (uintmax_t)getpid(), hostname);
 856                 }
 857                 if (args->check_self_contained_and_connected)
 858                         argv_array_push(&cmd.args, "--check-self-contained-and-connected");
 859                 if (args->from_promisor)
 860                         argv_array_push(&cmd.args, "--promisor");
 861         }
 862         else {
 863                 cmd_name = "unpack-objects";
 864                 argv_array_push(&cmd.args, cmd_name);
 865                 if (args->quiet || args->no_progress)
 866                         argv_array_push(&cmd.args, "-q");
 867                 args->check_self_contained_and_connected = 0;
 868         }
 869
 870         if (pass_header)
 871                 argv_array_pushf(&cmd.args, "--pack_header=%"PRIu32",%"PRIu32,
 872                                  ntohl(header.hdr_version),
 873                                  ntohl(header.hdr_entries));
 874         if (fetch_fsck_objects >= 0
 875             ? fetch_fsck_objects
 876             : transfer_fsck_objects >= 0
 877             ? transfer_fsck_objects
 878             : 0)
 879                 argv_array_push(&cmd.args, "--strict");
 880
 881         cmd.in = demux.out;
 882         cmd.git_cmd = 1;
 883         if (start_command(&cmd))
 884                 die(_("fetch-pack: unable to fork off %s"), cmd_name);
 885         if (do_keep && pack_lockfile) {
 886                 *pack_lockfile = index_pack_lockfile(cmd.out);
 887                 close(cmd.out);
 888         }
 889
 890         if (!use_sideband)
 891                 /* Closed by start_command() */
 892                 xd[0] = -1;
 893
 894         ret = finish_command(&cmd);
 895         if (!ret || (args->check_self_contained_and_connected && ret == 1))
 896                 args->self_contained_and_connected =
 897                         args->check_self_contained_and_connected &&
 898                         ret == 0;
 899         else
 900                 die(_("%s failed"), cmd_name);
 901         if (use_sideband && finish_async(&demux))
 902                 die(_("error in sideband demultiplexer"));
 903         return 0;
 904 }
 905
 906 static int cmp_ref_by_name(const void *a_, const void *b_)
 907 {
 908         const struct ref *a = *((const struct ref **)a_);
 909         const struct ref *b = *((const struct ref **)b_);
 910         return strcmp(a->name, b->name);
 911 }
 912
 913 static struct ref *do_fetch_pack(struct fetch_pack_args *args,
 914                                  int fd[2],
 915                                  const struct ref *orig_ref,
 916                                  struct ref **sought, int nr_sought,
 917                                  struct shallow_info *si,
 918                                  char **pack_lockfile)
 919 {
 920         struct ref *ref = copy_ref_list(orig_ref);
 921         struct object_id oid;
 922         const char *agent_feature;
 923         int agent_len;
 924
 925         sort_ref_list(&ref, ref_compare_name);
 926         QSORT(sought, nr_sought, cmp_ref_by_name);
 927
 928         if ((args->depth > 0 || is_repository_shallow()) && !server_supports("shallow"))
 929                 die(_("Server does not support shallow clients"));
 930         if (args->depth > 0 || args->deepen_since || args->deepen_not)
 931                 args->deepen = 1;
 932         if (server_supports("multi_ack_detailed")) {
 933                 print_verbose(args, _("Server supports multi_ack_detailed"));
 934                 multi_ack = 2;
 935                 if (server_supports("no-done")) {
 936                         print_verbose(args, _("Server supports no-done"));
 937                         if (args->stateless_rpc)
 938                                 no_done = 1;
 939                 }
 940         }
 941         else if (server_supports("multi_ack")) {
 942                 print_verbose(args, _("Server supports multi_ack"));
 943                 multi_ack = 1;
 944         }
 945         if (server_supports("side-band-64k")) {
 946                 print_verbose(args, _("Server supports side-band-64k"));
 947                 use_sideband = 2;
 948         }
 949         else if (server_supports("side-band")) {
 950                 print_verbose(args, _("Server supports side-band"));
 951                 use_sideband = 1;
 952         }
 953         if (server_supports("allow-tip-sha1-in-want")) {
 954                 print_verbose(args, _("Server supports allow-tip-sha1-in-want"));
 955                 allow_unadvertised_object_request |= ALLOW_TIP_SHA1;
 956         }
 957         if (server_supports("allow-reachable-sha1-in-want")) {
 958                 print_verbose(args, _("Server supports allow-reachable-sha1-in-want"));
 959                 allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
 960         }
 961         if (!server_supports("thin-pack"))
 962                 args->use_thin_pack = 0;
 963         if (!server_supports("no-progress"))
 964                 args->no_progress = 0;
 965         if (!server_supports("include-tag"))
 966                 args->include_tag = 0;
 967         if (server_supports("ofs-delta"))
 968                 print_verbose(args, _("Server supports ofs-delta"));
 969         else
 970                 prefer_ofs_delta = 0;
 971
 972         if ((agent_feature = server_feature_value("agent", &agent_len))) {
 973                 agent_supported = 1;
 974                 if (agent_len)
 975                         print_verbose(args, _("Server version is %.*s"),
 976                                       agent_len, agent_feature);
 977         }
 978         if (server_supports("deepen-since"))
 979                 deepen_since_ok = 1;
 980         else if (args->deepen_since)
 981                 die(_("Server does not support --shallow-since"));
 982         if (server_supports("deepen-not"))
 983                 deepen_not_ok = 1;
 984         else if (args->deepen_not)
 985                 die(_("Server does not support --shallow-exclude"));
 986         if (!server_supports("deepen-relative") && args->deepen_relative)
 987                 die(_("Server does not support --deepen"));
 988
 989         if (everything_local(args, &ref, sought, nr_sought)) {
 990                 packet_flush(fd[1]);
 991                 goto all_done;
 992         }
 993         if (find_common(args, fd, &oid, ref) < 0)
 994                 if (!args->keep_pack)
 995                         /* When cloning, it is not unusual to have
 996                          * no common commit.
 997                          */
 998                         warning(_("no common commits"));
 999
1000         if (args->stateless_rpc)
1001                 packet_flush(fd[1]);
1002         if (args->deepen)
1003                 setup_alternate_shallow(&shallow_lock, &alternate_shallow_file,
1004                                         NULL);
1005         else if (si->nr_ours || si->nr_theirs)
1006                 alternate_shallow_file = setup_temporary_shallow(si->shallow);
1007         else
1008                 alternate_shallow_file = NULL;
1009         if (get_pack(args, fd, pack_lockfile))
1010                 die(_("git fetch-pack: fetch failed."));
1011
1012  all_done:
1013         return ref;
1014 }
1015
1016 static void fetch_pack_config(void)
1017 {
1018         git_config_get_int("fetch.unpacklimit", &fetch_unpack_limit);
1019         git_config_get_int("transfer.unpacklimit", &transfer_unpack_limit);
1020         git_config_get_bool("repack.usedeltabaseoffset", &prefer_ofs_delta);
1021         git_config_get_bool("fetch.fsckobjects", &fetch_fsck_objects);
1022         git_config_get_bool("transfer.fsckobjects", &transfer_fsck_objects);
1023
1024         git_config(git_default_config, NULL);
1025 }
1026
1027 static void fetch_pack_setup(void)
1028 {
1029         static int did_setup;
1030         if (did_setup)
1031                 return;
1032         fetch_pack_config();
1033         if (0 <= transfer_unpack_limit)
1034                 unpack_limit = transfer_unpack_limit;
1035         else if (0 <= fetch_unpack_limit)
1036                 unpack_limit = fetch_unpack_limit;
1037         did_setup = 1;
1038 }
1039
1040 static int remove_duplicates_in_refs(struct ref **ref, int nr)
1041 {
1042         struct string_list names = STRING_LIST_INIT_NODUP;
1043         int src, dst;
1044
1045         for (src = dst = 0; src < nr; src++) {
1046                 struct string_list_item *item;
1047                 item = string_list_insert(&names, ref[src]->name);
1048                 if (item->util)
1049                         continue; /* already have it */
1050                 item->util = ref[src];
1051                 if (src != dst)
1052                         ref[dst] = ref[src];
1053                 dst++;
1054         }
1055         for (src = dst; src < nr; src++)
1056                 ref[src] = NULL;
1057         string_list_clear(&names, 0);
1058         return dst;
1059 }
1060
1061 static void update_shallow(struct fetch_pack_args *args,
1062                            struct ref **sought, int nr_sought,
1063                            struct shallow_info *si)
1064 {
1065         struct oid_array ref = OID_ARRAY_INIT;
1066         int *status;
1067         int i;
1068
1069         if (args->deepen && alternate_shallow_file) {
1070                 if (*alternate_shallow_file == '\0') { /* --unshallow */
1071                         unlink_or_warn(git_path_shallow());
1072                         rollback_lock_file(&shallow_lock);
1073                 } else
1074                         commit_lock_file(&shallow_lock);
1075                 return;
1076         }
1077
1078         if (!si->shallow || !si->shallow->nr)
1079                 return;
1080
1081         if (args->cloning) {
1082                 /*
1083                  * remote is shallow, but this is a clone, there are
1084                  * no objects in repo to worry about. Accept any
1085                  * shallow points that exist in the pack (iow in repo
1086                  * after get_pack() and reprepare_packed_git())
1087                  */
1088                 struct oid_array extra = OID_ARRAY_INIT;
1089                 struct object_id *oid = si->shallow->oid;
1090                 for (i = 0; i < si->shallow->nr; i++)
1091                         if (has_object_file(&oid[i]))
1092                                 oid_array_append(&extra, &oid[i]);
1093                 if (extra.nr) {
1094                         setup_alternate_shallow(&shallow_lock,
1095                                                 &alternate_shallow_file,
1096                                                 &extra);
1097                         commit_lock_file(&shallow_lock);
1098                 }
1099                 oid_array_clear(&extra);
1100                 return;
1101         }
1102
1103         if (!si->nr_ours && !si->nr_theirs)
1104                 return;
1105
1106         remove_nonexistent_theirs_shallow(si);
1107         if (!si->nr_ours && !si->nr_theirs)
1108                 return;
1109         for (i = 0; i < nr_sought; i++)
1110                 oid_array_append(&ref, &sought[i]->old_oid);
1111         si->ref = &ref;
1112
1113         if (args->update_shallow) {
1114                 /*
1115                  * remote is also shallow, .git/shallow may be updated
1116                  * so all refs can be accepted. Make sure we only add
1117                  * shallow roots that are actually reachable from new
1118                  * refs.
1119                  */
1120                 struct oid_array extra = OID_ARRAY_INIT;
1121                 struct object_id *oid = si->shallow->oid;
1122                 assign_shallow_commits_to_refs(si, NULL, NULL);
1123                 if (!si->nr_ours && !si->nr_theirs) {
1124                         oid_array_clear(&ref);
1125                         return;
1126                 }
1127                 for (i = 0; i < si->nr_ours; i++)
1128                         oid_array_append(&extra, &oid[si->ours[i]]);
1129                 for (i = 0; i < si->nr_theirs; i++)
1130                         oid_array_append(&extra, &oid[si->theirs[i]]);
1131                 setup_alternate_shallow(&shallow_lock,
1132                                         &alternate_shallow_file,
1133                                         &extra);
1134                 commit_lock_file(&shallow_lock);
1135                 oid_array_clear(&extra);
1136                 oid_array_clear(&ref);
1137                 return;
1138         }
1139
1140         /*
1141          * remote is also shallow, check what ref is safe to update
1142          * without updating .git/shallow
1143          */
1144         status = xcalloc(nr_sought, sizeof(*status));
1145         assign_shallow_commits_to_refs(si, NULL, status);
1146         if (si->nr_ours || si->nr_theirs) {
1147                 for (i = 0; i < nr_sought; i++)
1148                         if (status[i])
1149                                 sought[i]->status = REF_STATUS_REJECT_SHALLOW;
1150         }
1151         free(status);
1152         oid_array_clear(&ref);
1153 }
1154
1155 struct ref *fetch_pack(struct fetch_pack_args *args,
1156                        int fd[], struct child_process *conn,
1157                        const struct ref *ref,
1158                        const char *dest,
1159                        struct ref **sought, int nr_sought,
1160                        struct oid_array *shallow,
1161                        char **pack_lockfile)
1162 {
1163         struct ref *ref_cpy;
1164         struct shallow_info si;
1165
1166         fetch_pack_setup();
1167         if (nr_sought)
1168                 nr_sought = remove_duplicates_in_refs(sought, nr_sought);
1169
1170         if (!ref) {
1171                 packet_flush(fd[1]);
1172                 die(_("no matching remote head"));
1173         }
1174         prepare_shallow_info(&si, shallow);
1175         ref_cpy = do_fetch_pack(args, fd, ref, sought, nr_sought,
1176                                 &si, pack_lockfile);
1177         reprepare_packed_git();
1178         update_shallow(args, sought, nr_sought, &si);
1179         clear_shallow_info(&si);
1180         return ref_cpy;
1181 }
1182
1183 int report_unmatched_refs(struct ref **sought, int nr_sought)
1184 {
1185         int i, ret = 0;
1186
1187         for (i = 0; i < nr_sought; i++) {
1188                 if (!sought[i])
1189                         continue;
1190                 switch (sought[i]->match_status) {
1191                 case REF_MATCHED:
1192                         continue;
1193                 case REF_NOT_MATCHED:
1194                         error(_("no such remote ref %s"), sought[i]->name);
1195                         break;
1196                 case REF_UNADVERTISED_NOT_ALLOWED:
1197                         error(_("Server does not allow request for unadvertised object %s"),
1198                               sought[i]->name);
1199                         break;
1200                 }
1201                 ret = 1;
1202         }
1203         return ret;
1204 }