fetch-pack.con commit Merge branch 'tb/banned-vsprintf-namefix' (37801f0)
   1#include "cache.h"
   2#include "repository.h"
   3#include "config.h"
   4#include "lockfile.h"
   5#include "refs.h"
   6#include "pkt-line.h"
   7#include "commit.h"
   8#include "tag.h"
   9#include "exec-cmd.h"
  10#include "pack.h"
  11#include "sideband.h"
  12#include "fetch-pack.h"
  13#include "remote.h"
  14#include "run-command.h"
  15#include "connect.h"
  16#include "transport.h"
  17#include "version.h"
  18#include "sha1-array.h"
  19#include "oidset.h"
  20#include "packfile.h"
  21#include "object-store.h"
  22#include "connected.h"
  23#include "fetch-negotiator.h"
  24#include "fsck.h"
  25
  26static int transfer_unpack_limit = -1;
  27static int fetch_unpack_limit = -1;
  28static int unpack_limit = 100;
  29static int prefer_ofs_delta = 1;
  30static int no_done;
  31static int deepen_since_ok;
  32static int deepen_not_ok;
  33static int fetch_fsck_objects = -1;
  34static int transfer_fsck_objects = -1;
  35static int agent_supported;
  36static int server_supports_filtering;
  37static struct lock_file shallow_lock;
  38static const char *alternate_shallow_file;
  39static struct strbuf fsck_msg_types = STRBUF_INIT;
  40
  41/* Remember to update object flag allocation in object.h */
  42#define COMPLETE        (1U << 0)
  43#define ALTERNATE       (1U << 1)
  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
  51static int multi_ack, use_sideband;
  52/* Allow specifying sha1 if it is a ref tip. */
  53#define ALLOW_TIP_SHA1  01
  54/* Allow request of a sha1 if it is reachable from a ref (possibly hidden ref). */
  55#define ALLOW_REACHABLE_SHA1    02
  56static unsigned int allow_unadvertised_object_request;
  57
  58__attribute__((format (printf, 2, 3)))
  59static inline void print_verbose(const struct fetch_pack_args *args,
  60                                 const char *fmt, ...)
  61{
  62        va_list params;
  63
  64        if (!args->verbose)
  65                return;
  66
  67        va_start(params, fmt);
  68        vfprintf(stderr, fmt, params);
  69        va_end(params);
  70        fputc('\n', stderr);
  71}
  72
  73struct alternate_object_cache {
  74        struct object **items;
  75        size_t nr, alloc;
  76};
  77
  78static void cache_one_alternate(const struct object_id *oid,
  79                                void *vcache)
  80{
  81        struct alternate_object_cache *cache = vcache;
  82        struct object *obj = parse_object(the_repository, oid);
  83
  84        if (!obj || (obj->flags & ALTERNATE))
  85                return;
  86
  87        obj->flags |= ALTERNATE;
  88        ALLOC_GROW(cache->items, cache->nr + 1, cache->alloc);
  89        cache->items[cache->nr++] = obj;
  90}
  91
  92static void for_each_cached_alternate(struct fetch_negotiator *negotiator,
  93                                      void (*cb)(struct fetch_negotiator *,
  94                                                 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(negotiator, cache.items[i]);
 107}
 108
 109static int rev_list_insert_ref(struct fetch_negotiator *negotiator,
 110                               const char *refname,
 111                               const struct object_id *oid)
 112{
 113        struct object *o = deref_tag(the_repository,
 114                                     parse_object(the_repository, oid),
 115                                     refname, 0);
 116
 117        if (o && o->type == OBJ_COMMIT)
 118                negotiator->add_tip(negotiator, (struct commit *)o);
 119
 120        return 0;
 121}
 122
 123static int rev_list_insert_ref_oid(const char *refname, const struct object_id *oid,
 124                                   int flag, void *cb_data)
 125{
 126        return rev_list_insert_ref(cb_data, refname, oid);
 127}
 128
 129enum ack_type {
 130        NAK = 0,
 131        ACK,
 132        ACK_continue,
 133        ACK_common,
 134        ACK_ready
 135};
 136
 137static void consume_shallow_list(struct fetch_pack_args *args,
 138                                 struct packet_reader *reader)
 139{
 140        if (args->stateless_rpc && args->deepen) {
 141                /* If we sent a depth we will get back "duplicate"
 142                 * shallow and unshallow commands every time there
 143                 * is a block of have lines exchanged.
 144                 */
 145                while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
 146                        if (starts_with(reader->line, "shallow "))
 147                                continue;
 148                        if (starts_with(reader->line, "unshallow "))
 149                                continue;
 150                        die(_("git fetch-pack: expected shallow list"));
 151                }
 152                if (reader->status != PACKET_READ_FLUSH)
 153                        die(_("git fetch-pack: expected a flush packet after shallow list"));
 154        }
 155}
 156
 157static enum ack_type get_ack(struct packet_reader *reader,
 158                             struct object_id *result_oid)
 159{
 160        int len;
 161        const char *arg;
 162
 163        if (packet_reader_read(reader) != PACKET_READ_NORMAL)
 164                die(_("git fetch-pack: expected ACK/NAK, got a flush packet"));
 165        len = reader->pktlen;
 166
 167        if (!strcmp(reader->line, "NAK"))
 168                return NAK;
 169        if (skip_prefix(reader->line, "ACK ", &arg)) {
 170                if (!get_oid_hex(arg, result_oid)) {
 171                        arg += 40;
 172                        len -= arg - reader->line;
 173                        if (len < 1)
 174                                return ACK;
 175                        if (strstr(arg, "continue"))
 176                                return ACK_continue;
 177                        if (strstr(arg, "common"))
 178                                return ACK_common;
 179                        if (strstr(arg, "ready"))
 180                                return ACK_ready;
 181                        return ACK;
 182                }
 183        }
 184        die(_("git fetch-pack: expected ACK/NAK, got '%s'"), reader->line);
 185}
 186
 187static void send_request(struct fetch_pack_args *args,
 188                         int fd, struct strbuf *buf)
 189{
 190        if (args->stateless_rpc) {
 191                send_sideband(fd, -1, buf->buf, buf->len, LARGE_PACKET_MAX);
 192                packet_flush(fd);
 193        } else {
 194                if (write_in_full(fd, buf->buf, buf->len) < 0)
 195                        die_errno(_("unable to write to remote"));
 196        }
 197}
 198
 199static void insert_one_alternate_object(struct fetch_negotiator *negotiator,
 200                                        struct object *obj)
 201{
 202        rev_list_insert_ref(negotiator, NULL, &obj->oid);
 203}
 204
 205#define INITIAL_FLUSH 16
 206#define PIPESAFE_FLUSH 32
 207#define LARGE_FLUSH 16384
 208
 209static int next_flush(int stateless_rpc, int count)
 210{
 211        if (stateless_rpc) {
 212                if (count < LARGE_FLUSH)
 213                        count <<= 1;
 214                else
 215                        count = count * 11 / 10;
 216        } else {
 217                if (count < PIPESAFE_FLUSH)
 218                        count <<= 1;
 219                else
 220                        count += PIPESAFE_FLUSH;
 221        }
 222        return count;
 223}
 224
 225static void mark_tips(struct fetch_negotiator *negotiator,
 226                      const struct oid_array *negotiation_tips)
 227{
 228        int i;
 229
 230        if (!negotiation_tips) {
 231                for_each_ref(rev_list_insert_ref_oid, negotiator);
 232                return;
 233        }
 234
 235        for (i = 0; i < negotiation_tips->nr; i++)
 236                rev_list_insert_ref(negotiator, NULL,
 237                                    &negotiation_tips->oid[i]);
 238        return;
 239}
 240
 241static int find_common(struct fetch_negotiator *negotiator,
 242                       struct fetch_pack_args *args,
 243                       int fd[2], struct object_id *result_oid,
 244                       struct ref *refs)
 245{
 246        int fetching;
 247        int count = 0, flushes = 0, flush_at = INITIAL_FLUSH, retval;
 248        const struct object_id *oid;
 249        unsigned in_vain = 0;
 250        int got_continue = 0;
 251        int got_ready = 0;
 252        struct strbuf req_buf = STRBUF_INIT;
 253        size_t state_len = 0;
 254        struct packet_reader reader;
 255
 256        if (args->stateless_rpc && multi_ack == 1)
 257                die(_("--stateless-rpc requires multi_ack_detailed"));
 258
 259        packet_reader_init(&reader, fd[0], NULL, 0,
 260                           PACKET_READ_CHOMP_NEWLINE |
 261                           PACKET_READ_DIE_ON_ERR_PACKET);
 262
 263        if (!args->no_dependents) {
 264                mark_tips(negotiator, args->negotiation_tips);
 265                for_each_cached_alternate(negotiator, insert_one_alternate_object);
 266        }
 267
 268        fetching = 0;
 269        for ( ; refs ; refs = refs->next) {
 270                struct object_id *remote = &refs->old_oid;
 271                const char *remote_hex;
 272                struct object *o;
 273
 274                /*
 275                 * If that object is complete (i.e. it is an ancestor of a
 276                 * local ref), we tell them we have it but do not have to
 277                 * tell them about its ancestors, which they already know
 278                 * about.
 279                 *
 280                 * We use lookup_object here because we are only
 281                 * interested in the case we *know* the object is
 282                 * reachable and we have already scanned it.
 283                 *
 284                 * Do this only if args->no_dependents is false (if it is true,
 285                 * we cannot trust the object flags).
 286                 */
 287                if (!args->no_dependents &&
 288                    ((o = lookup_object(the_repository, remote)) != NULL) &&
 289                                (o->flags & COMPLETE)) {
 290                        continue;
 291                }
 292
 293                remote_hex = oid_to_hex(remote);
 294                if (!fetching) {
 295                        struct strbuf c = STRBUF_INIT;
 296                        if (multi_ack == 2)     strbuf_addstr(&c, " multi_ack_detailed");
 297                        if (multi_ack == 1)     strbuf_addstr(&c, " multi_ack");
 298                        if (no_done)            strbuf_addstr(&c, " no-done");
 299                        if (use_sideband == 2)  strbuf_addstr(&c, " side-band-64k");
 300                        if (use_sideband == 1)  strbuf_addstr(&c, " side-band");
 301                        if (args->deepen_relative) strbuf_addstr(&c, " deepen-relative");
 302                        if (args->use_thin_pack) strbuf_addstr(&c, " thin-pack");
 303                        if (args->no_progress)   strbuf_addstr(&c, " no-progress");
 304                        if (args->include_tag)   strbuf_addstr(&c, " include-tag");
 305                        if (prefer_ofs_delta)   strbuf_addstr(&c, " ofs-delta");
 306                        if (deepen_since_ok)    strbuf_addstr(&c, " deepen-since");
 307                        if (deepen_not_ok)      strbuf_addstr(&c, " deepen-not");
 308                        if (agent_supported)    strbuf_addf(&c, " agent=%s",
 309                                                            git_user_agent_sanitized());
 310                        if (args->filter_options.choice)
 311                                strbuf_addstr(&c, " filter");
 312                        packet_buf_write(&req_buf, "want %s%s\n", remote_hex, c.buf);
 313                        strbuf_release(&c);
 314                } else
 315                        packet_buf_write(&req_buf, "want %s\n", remote_hex);
 316                fetching++;
 317        }
 318
 319        if (!fetching) {
 320                strbuf_release(&req_buf);
 321                packet_flush(fd[1]);
 322                return 1;
 323        }
 324
 325        if (is_repository_shallow(the_repository))
 326                write_shallow_commits(&req_buf, 1, NULL);
 327        if (args->depth > 0)
 328                packet_buf_write(&req_buf, "deepen %d", args->depth);
 329        if (args->deepen_since) {
 330                timestamp_t max_age = approxidate(args->deepen_since);
 331                packet_buf_write(&req_buf, "deepen-since %"PRItime, max_age);
 332        }
 333        if (args->deepen_not) {
 334                int i;
 335                for (i = 0; i < args->deepen_not->nr; i++) {
 336                        struct string_list_item *s = args->deepen_not->items + i;
 337                        packet_buf_write(&req_buf, "deepen-not %s", s->string);
 338                }
 339        }
 340        if (server_supports_filtering && args->filter_options.choice) {
 341                const char *spec =
 342                        expand_list_objects_filter_spec(&args->filter_options);
 343                packet_buf_write(&req_buf, "filter %s", spec);
 344        }
 345        packet_buf_flush(&req_buf);
 346        state_len = req_buf.len;
 347
 348        if (args->deepen) {
 349                const char *arg;
 350                struct object_id oid;
 351
 352                send_request(args, fd[1], &req_buf);
 353                while (packet_reader_read(&reader) == PACKET_READ_NORMAL) {
 354                        if (skip_prefix(reader.line, "shallow ", &arg)) {
 355                                if (get_oid_hex(arg, &oid))
 356                                        die(_("invalid shallow line: %s"), reader.line);
 357                                register_shallow(the_repository, &oid);
 358                                continue;
 359                        }
 360                        if (skip_prefix(reader.line, "unshallow ", &arg)) {
 361                                if (get_oid_hex(arg, &oid))
 362                                        die(_("invalid unshallow line: %s"), reader.line);
 363                                if (!lookup_object(the_repository, &oid))
 364                                        die(_("object not found: %s"), reader.line);
 365                                /* make sure that it is parsed as shallow */
 366                                if (!parse_object(the_repository, &oid))
 367                                        die(_("error in object: %s"), reader.line);
 368                                if (unregister_shallow(&oid))
 369                                        die(_("no shallow found: %s"), reader.line);
 370                                continue;
 371                        }
 372                        die(_("expected shallow/unshallow, got %s"), reader.line);
 373                }
 374        } else if (!args->stateless_rpc)
 375                send_request(args, fd[1], &req_buf);
 376
 377        if (!args->stateless_rpc) {
 378                /* If we aren't using the stateless-rpc interface
 379                 * we don't need to retain the headers.
 380                 */
 381                strbuf_setlen(&req_buf, 0);
 382                state_len = 0;
 383        }
 384
 385        flushes = 0;
 386        retval = -1;
 387        if (args->no_dependents)
 388                goto done;
 389        while ((oid = negotiator->next(negotiator))) {
 390                packet_buf_write(&req_buf, "have %s\n", oid_to_hex(oid));
 391                print_verbose(args, "have %s", oid_to_hex(oid));
 392                in_vain++;
 393                if (flush_at <= ++count) {
 394                        int ack;
 395
 396                        packet_buf_flush(&req_buf);
 397                        send_request(args, fd[1], &req_buf);
 398                        strbuf_setlen(&req_buf, state_len);
 399                        flushes++;
 400                        flush_at = next_flush(args->stateless_rpc, count);
 401
 402                        /*
 403                         * We keep one window "ahead" of the other side, and
 404                         * will wait for an ACK only on the next one
 405                         */
 406                        if (!args->stateless_rpc && count == INITIAL_FLUSH)
 407                                continue;
 408
 409                        consume_shallow_list(args, &reader);
 410                        do {
 411                                ack = get_ack(&reader, result_oid);
 412                                if (ack)
 413                                        print_verbose(args, _("got %s %d %s"), "ack",
 414                                                      ack, oid_to_hex(result_oid));
 415                                switch (ack) {
 416                                case ACK:
 417                                        flushes = 0;
 418                                        multi_ack = 0;
 419                                        retval = 0;
 420                                        goto done;
 421                                case ACK_common:
 422                                case ACK_ready:
 423                                case ACK_continue: {
 424                                        struct commit *commit =
 425                                                lookup_commit(the_repository,
 426                                                              result_oid);
 427                                        int was_common;
 428
 429                                        if (!commit)
 430                                                die(_("invalid commit %s"), oid_to_hex(result_oid));
 431                                        was_common = negotiator->ack(negotiator, commit);
 432                                        if (args->stateless_rpc
 433                                         && ack == ACK_common
 434                                         && !was_common) {
 435                                                /* We need to replay the have for this object
 436                                                 * on the next RPC request so the peer knows
 437                                                 * it is in common with us.
 438                                                 */
 439                                                const char *hex = oid_to_hex(result_oid);
 440                                                packet_buf_write(&req_buf, "have %s\n", hex);
 441                                                state_len = req_buf.len;
 442                                                /*
 443                                                 * Reset in_vain because an ack
 444                                                 * for this commit has not been
 445                                                 * seen.
 446                                                 */
 447                                                in_vain = 0;
 448                                        } else if (!args->stateless_rpc
 449                                                   || ack != ACK_common)
 450                                                in_vain = 0;
 451                                        retval = 0;
 452                                        got_continue = 1;
 453                                        if (ack == ACK_ready)
 454                                                got_ready = 1;
 455                                        break;
 456                                        }
 457                                }
 458                        } while (ack);
 459                        flushes--;
 460                        if (got_continue && MAX_IN_VAIN < in_vain) {
 461                                print_verbose(args, _("giving up"));
 462                                break; /* give up */
 463                        }
 464                        if (got_ready)
 465                                break;
 466                }
 467        }
 468done:
 469        if (!got_ready || !no_done) {
 470                packet_buf_write(&req_buf, "done\n");
 471                send_request(args, fd[1], &req_buf);
 472        }
 473        print_verbose(args, _("done"));
 474        if (retval != 0) {
 475                multi_ack = 0;
 476                flushes++;
 477        }
 478        strbuf_release(&req_buf);
 479
 480        if (!got_ready || !no_done)
 481                consume_shallow_list(args, &reader);
 482        while (flushes || multi_ack) {
 483                int ack = get_ack(&reader, result_oid);
 484                if (ack) {
 485                        print_verbose(args, _("got %s (%d) %s"), "ack",
 486                                      ack, oid_to_hex(result_oid));
 487                        if (ack == ACK)
 488                                return 0;
 489                        multi_ack = 1;
 490                        continue;
 491                }
 492                flushes--;
 493        }
 494        /* it is no error to fetch into a completely empty repo */
 495        return count ? retval : 0;
 496}
 497
 498static struct commit_list *complete;
 499
 500static int mark_complete(const struct object_id *oid)
 501{
 502        struct object *o = parse_object(the_repository, oid);
 503
 504        while (o && o->type == OBJ_TAG) {
 505                struct tag *t = (struct tag *) o;
 506                if (!t->tagged)
 507                        break; /* broken repository */
 508                o->flags |= COMPLETE;
 509                o = parse_object(the_repository, &t->tagged->oid);
 510        }
 511        if (o && o->type == OBJ_COMMIT) {
 512                struct commit *commit = (struct commit *)o;
 513                if (!(commit->object.flags & COMPLETE)) {
 514                        commit->object.flags |= COMPLETE;
 515                        commit_list_insert(commit, &complete);
 516                }
 517        }
 518        return 0;
 519}
 520
 521static int mark_complete_oid(const char *refname, const struct object_id *oid,
 522                             int flag, void *cb_data)
 523{
 524        return mark_complete(oid);
 525}
 526
 527static void mark_recent_complete_commits(struct fetch_pack_args *args,
 528                                         timestamp_t cutoff)
 529{
 530        while (complete && cutoff <= complete->item->date) {
 531                print_verbose(args, _("Marking %s as complete"),
 532                              oid_to_hex(&complete->item->object.oid));
 533                pop_most_recent_commit(&complete, COMPLETE);
 534        }
 535}
 536
 537static void add_refs_to_oidset(struct oidset *oids, struct ref *refs)
 538{
 539        for (; refs; refs = refs->next)
 540                oidset_insert(oids, &refs->old_oid);
 541}
 542
 543static int is_unmatched_ref(const struct ref *ref)
 544{
 545        struct object_id oid;
 546        const char *p;
 547        return  ref->match_status == REF_NOT_MATCHED &&
 548                !parse_oid_hex(ref->name, &oid, &p) &&
 549                *p == '\0' &&
 550                oideq(&oid, &ref->old_oid);
 551}
 552
 553static void filter_refs(struct fetch_pack_args *args,
 554                        struct ref **refs,
 555                        struct ref **sought, int nr_sought)
 556{
 557        struct ref *newlist = NULL;
 558        struct ref **newtail = &newlist;
 559        struct ref *unmatched = NULL;
 560        struct ref *ref, *next;
 561        struct oidset tip_oids = OIDSET_INIT;
 562        int i;
 563        int strict = !(allow_unadvertised_object_request &
 564                       (ALLOW_TIP_SHA1 | ALLOW_REACHABLE_SHA1));
 565
 566        i = 0;
 567        for (ref = *refs; ref; ref = next) {
 568                int keep = 0;
 569                next = ref->next;
 570
 571                if (starts_with(ref->name, "refs/") &&
 572                    check_refname_format(ref->name, 0)) {
 573                        /*
 574                         * trash or a peeled value; do not even add it to
 575                         * unmatched list
 576                         */
 577                        free_one_ref(ref);
 578                        continue;
 579                } else {
 580                        while (i < nr_sought) {
 581                                int cmp = strcmp(ref->name, sought[i]->name);
 582                                if (cmp < 0)
 583                                        break; /* definitely do not have it */
 584                                else if (cmp == 0) {
 585                                        keep = 1; /* definitely have it */
 586                                        sought[i]->match_status = REF_MATCHED;
 587                                }
 588                                i++;
 589                        }
 590
 591                        if (!keep && args->fetch_all &&
 592                            (!args->deepen || !starts_with(ref->name, "refs/tags/")))
 593                                keep = 1;
 594                }
 595
 596                if (keep) {
 597                        *newtail = ref;
 598                        ref->next = NULL;
 599                        newtail = &ref->next;
 600                } else {
 601                        ref->next = unmatched;
 602                        unmatched = ref;
 603                }
 604        }
 605
 606        if (strict) {
 607                for (i = 0; i < nr_sought; i++) {
 608                        ref = sought[i];
 609                        if (!is_unmatched_ref(ref))
 610                                continue;
 611
 612                        add_refs_to_oidset(&tip_oids, unmatched);
 613                        add_refs_to_oidset(&tip_oids, newlist);
 614                        break;
 615                }
 616        }
 617
 618        /* Append unmatched requests to the list */
 619        for (i = 0; i < nr_sought; i++) {
 620                ref = sought[i];
 621                if (!is_unmatched_ref(ref))
 622                        continue;
 623
 624                if (!strict || oidset_contains(&tip_oids, &ref->old_oid)) {
 625                        ref->match_status = REF_MATCHED;
 626                        *newtail = copy_ref(ref);
 627                        newtail = &(*newtail)->next;
 628                } else {
 629                        ref->match_status = REF_UNADVERTISED_NOT_ALLOWED;
 630                }
 631        }
 632
 633        oidset_clear(&tip_oids);
 634        free_refs(unmatched);
 635
 636        *refs = newlist;
 637}
 638
 639static void mark_alternate_complete(struct fetch_negotiator *unused,
 640                                    struct object *obj)
 641{
 642        mark_complete(&obj->oid);
 643}
 644
 645struct loose_object_iter {
 646        struct oidset *loose_object_set;
 647        struct ref *refs;
 648};
 649
 650/*
 651 * Mark recent commits available locally and reachable from a local ref as
 652 * COMPLETE. If args->no_dependents is false, also mark COMPLETE remote refs as
 653 * COMMON_REF (otherwise, we are not planning to participate in negotiation, and
 654 * thus do not need COMMON_REF marks).
 655 *
 656 * The cutoff time for recency is determined by this heuristic: it is the
 657 * earliest commit time of the objects in refs that are commits and that we know
 658 * the commit time of.
 659 */
 660static void mark_complete_and_common_ref(struct fetch_negotiator *negotiator,
 661                                         struct fetch_pack_args *args,
 662                                         struct ref **refs)
 663{
 664        struct ref *ref;
 665        int old_save_commit_buffer = save_commit_buffer;
 666        timestamp_t cutoff = 0;
 667
 668        save_commit_buffer = 0;
 669
 670        for (ref = *refs; ref; ref = ref->next) {
 671                struct object *o;
 672
 673                if (!has_object_file_with_flags(&ref->old_oid,
 674                                                OBJECT_INFO_QUICK))
 675                        continue;
 676                o = parse_object(the_repository, &ref->old_oid);
 677                if (!o)
 678                        continue;
 679
 680                /* We already have it -- which may mean that we were
 681                 * in sync with the other side at some time after
 682                 * that (it is OK if we guess wrong here).
 683                 */
 684                if (o->type == OBJ_COMMIT) {
 685                        struct commit *commit = (struct commit *)o;
 686                        if (!cutoff || cutoff < commit->date)
 687                                cutoff = commit->date;
 688                }
 689        }
 690
 691        if (!args->deepen) {
 692                for_each_ref(mark_complete_oid, NULL);
 693                for_each_cached_alternate(NULL, mark_alternate_complete);
 694                commit_list_sort_by_date(&complete);
 695                if (cutoff)
 696                        mark_recent_complete_commits(args, cutoff);
 697        }
 698
 699        /*
 700         * Mark all complete remote refs as common refs.
 701         * Don't mark them common yet; the server has to be told so first.
 702         */
 703        for (ref = *refs; ref; ref = ref->next) {
 704                struct object *o = deref_tag(the_repository,
 705                                             lookup_object(the_repository,
 706                                             &ref->old_oid),
 707                                             NULL, 0);
 708
 709                if (!o || o->type != OBJ_COMMIT || !(o->flags & COMPLETE))
 710                        continue;
 711
 712                negotiator->known_common(negotiator,
 713                                         (struct commit *)o);
 714        }
 715
 716        save_commit_buffer = old_save_commit_buffer;
 717}
 718
 719/*
 720 * Returns 1 if every object pointed to by the given remote refs is available
 721 * locally and reachable from a local ref, and 0 otherwise.
 722 */
 723static int everything_local(struct fetch_pack_args *args,
 724                            struct ref **refs)
 725{
 726        struct ref *ref;
 727        int retval;
 728
 729        for (retval = 1, ref = *refs; ref ; ref = ref->next) {
 730                const struct object_id *remote = &ref->old_oid;
 731                struct object *o;
 732
 733                o = lookup_object(the_repository, remote);
 734                if (!o || !(o->flags & COMPLETE)) {
 735                        retval = 0;
 736                        print_verbose(args, "want %s (%s)", oid_to_hex(remote),
 737                                      ref->name);
 738                        continue;
 739                }
 740                print_verbose(args, _("already have %s (%s)"), oid_to_hex(remote),
 741                              ref->name);
 742        }
 743
 744        return retval;
 745}
 746
 747static int sideband_demux(int in, int out, void *data)
 748{
 749        int *xd = data;
 750        int ret;
 751
 752        ret = recv_sideband("fetch-pack", xd[0], out);
 753        close(out);
 754        return ret;
 755}
 756
 757static int get_pack(struct fetch_pack_args *args,
 758                    int xd[2], char **pack_lockfile)
 759{
 760        struct async demux;
 761        int do_keep = args->keep_pack;
 762        const char *cmd_name;
 763        struct pack_header header;
 764        int pass_header = 0;
 765        struct child_process cmd = CHILD_PROCESS_INIT;
 766        int ret;
 767
 768        memset(&demux, 0, sizeof(demux));
 769        if (use_sideband) {
 770                /* xd[] is talking with upload-pack; subprocess reads from
 771                 * xd[0], spits out band#2 to stderr, and feeds us band#1
 772                 * through demux->out.
 773                 */
 774                demux.proc = sideband_demux;
 775                demux.data = xd;
 776                demux.out = -1;
 777                demux.isolate_sigpipe = 1;
 778                if (start_async(&demux))
 779                        die(_("fetch-pack: unable to fork off sideband demultiplexer"));
 780        }
 781        else
 782                demux.out = xd[0];
 783
 784        if (!args->keep_pack && unpack_limit) {
 785
 786                if (read_pack_header(demux.out, &header))
 787                        die(_("protocol error: bad pack header"));
 788                pass_header = 1;
 789                if (ntohl(header.hdr_entries) < unpack_limit)
 790                        do_keep = 0;
 791                else
 792                        do_keep = 1;
 793        }
 794
 795        if (alternate_shallow_file) {
 796                argv_array_push(&cmd.args, "--shallow-file");
 797                argv_array_push(&cmd.args, alternate_shallow_file);
 798        }
 799
 800        if (do_keep || args->from_promisor) {
 801                if (pack_lockfile)
 802                        cmd.out = -1;
 803                cmd_name = "index-pack";
 804                argv_array_push(&cmd.args, cmd_name);
 805                argv_array_push(&cmd.args, "--stdin");
 806                if (!args->quiet && !args->no_progress)
 807                        argv_array_push(&cmd.args, "-v");
 808                if (args->use_thin_pack)
 809                        argv_array_push(&cmd.args, "--fix-thin");
 810                if (do_keep && (args->lock_pack || unpack_limit)) {
 811                        char hostname[HOST_NAME_MAX + 1];
 812                        if (xgethostname(hostname, sizeof(hostname)))
 813                                xsnprintf(hostname, sizeof(hostname), "localhost");
 814                        argv_array_pushf(&cmd.args,
 815                                        "--keep=fetch-pack %"PRIuMAX " on %s",
 816                                        (uintmax_t)getpid(), hostname);
 817                }
 818                if (args->check_self_contained_and_connected)
 819                        argv_array_push(&cmd.args, "--check-self-contained-and-connected");
 820                if (args->from_promisor)
 821                        argv_array_push(&cmd.args, "--promisor");
 822        }
 823        else {
 824                cmd_name = "unpack-objects";
 825                argv_array_push(&cmd.args, cmd_name);
 826                if (args->quiet || args->no_progress)
 827                        argv_array_push(&cmd.args, "-q");
 828                args->check_self_contained_and_connected = 0;
 829        }
 830
 831        if (pass_header)
 832                argv_array_pushf(&cmd.args, "--pack_header=%"PRIu32",%"PRIu32,
 833                                 ntohl(header.hdr_version),
 834                                 ntohl(header.hdr_entries));
 835        if (fetch_fsck_objects >= 0
 836            ? fetch_fsck_objects
 837            : transfer_fsck_objects >= 0
 838            ? transfer_fsck_objects
 839            : 0) {
 840                if (args->from_promisor)
 841                        /*
 842                         * We cannot use --strict in index-pack because it
 843                         * checks both broken objects and links, but we only
 844                         * want to check for broken objects.
 845                         */
 846                        argv_array_push(&cmd.args, "--fsck-objects");
 847                else
 848                        argv_array_pushf(&cmd.args, "--strict%s",
 849                                         fsck_msg_types.buf);
 850        }
 851
 852        cmd.in = demux.out;
 853        cmd.git_cmd = 1;
 854        if (start_command(&cmd))
 855                die(_("fetch-pack: unable to fork off %s"), cmd_name);
 856        if (do_keep && pack_lockfile) {
 857                *pack_lockfile = index_pack_lockfile(cmd.out);
 858                close(cmd.out);
 859        }
 860
 861        if (!use_sideband)
 862                /* Closed by start_command() */
 863                xd[0] = -1;
 864
 865        ret = finish_command(&cmd);
 866        if (!ret || (args->check_self_contained_and_connected && ret == 1))
 867                args->self_contained_and_connected =
 868                        args->check_self_contained_and_connected &&
 869                        ret == 0;
 870        else
 871                die(_("%s failed"), cmd_name);
 872        if (use_sideband && finish_async(&demux))
 873                die(_("error in sideband demultiplexer"));
 874        return 0;
 875}
 876
 877static int cmp_ref_by_name(const void *a_, const void *b_)
 878{
 879        const struct ref *a = *((const struct ref **)a_);
 880        const struct ref *b = *((const struct ref **)b_);
 881        return strcmp(a->name, b->name);
 882}
 883
 884static struct ref *do_fetch_pack(struct fetch_pack_args *args,
 885                                 int fd[2],
 886                                 const struct ref *orig_ref,
 887                                 struct ref **sought, int nr_sought,
 888                                 struct shallow_info *si,
 889                                 char **pack_lockfile)
 890{
 891        struct repository *r = the_repository;
 892        struct ref *ref = copy_ref_list(orig_ref);
 893        struct object_id oid;
 894        const char *agent_feature;
 895        int agent_len;
 896        struct fetch_negotiator negotiator;
 897        fetch_negotiator_init(r, &negotiator);
 898
 899        sort_ref_list(&ref, ref_compare_name);
 900        QSORT(sought, nr_sought, cmp_ref_by_name);
 901
 902        if ((agent_feature = server_feature_value("agent", &agent_len))) {
 903                agent_supported = 1;
 904                if (agent_len)
 905                        print_verbose(args, _("Server version is %.*s"),
 906                                      agent_len, agent_feature);
 907        }
 908
 909        if (server_supports("shallow"))
 910                print_verbose(args, _("Server supports %s"), "shallow");
 911        else if (args->depth > 0 || is_repository_shallow(r))
 912                die(_("Server does not support shallow clients"));
 913        if (args->depth > 0 || args->deepen_since || args->deepen_not)
 914                args->deepen = 1;
 915        if (server_supports("multi_ack_detailed")) {
 916                print_verbose(args, _("Server supports %s"), "multi_ack_detailed");
 917                multi_ack = 2;
 918                if (server_supports("no-done")) {
 919                        print_verbose(args, _("Server supports %s"), "no-done");
 920                        if (args->stateless_rpc)
 921                                no_done = 1;
 922                }
 923        }
 924        else if (server_supports("multi_ack")) {
 925                print_verbose(args, _("Server supports %s"), "multi_ack");
 926                multi_ack = 1;
 927        }
 928        if (server_supports("side-band-64k")) {
 929                print_verbose(args, _("Server supports %s"), "side-band-64k");
 930                use_sideband = 2;
 931        }
 932        else if (server_supports("side-band")) {
 933                print_verbose(args, _("Server supports %s"), "side-band");
 934                use_sideband = 1;
 935        }
 936        if (server_supports("allow-tip-sha1-in-want")) {
 937                print_verbose(args, _("Server supports %s"), "allow-tip-sha1-in-want");
 938                allow_unadvertised_object_request |= ALLOW_TIP_SHA1;
 939        }
 940        if (server_supports("allow-reachable-sha1-in-want")) {
 941                print_verbose(args, _("Server supports %s"), "allow-reachable-sha1-in-want");
 942                allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
 943        }
 944        if (server_supports("thin-pack"))
 945                print_verbose(args, _("Server supports %s"), "thin-pack");
 946        else
 947                args->use_thin_pack = 0;
 948        if (server_supports("no-progress"))
 949                print_verbose(args, _("Server supports %s"), "no-progress");
 950        else
 951                args->no_progress = 0;
 952        if (server_supports("include-tag"))
 953                print_verbose(args, _("Server supports %s"), "include-tag");
 954        else
 955                args->include_tag = 0;
 956        if (server_supports("ofs-delta"))
 957                print_verbose(args, _("Server supports %s"), "ofs-delta");
 958        else
 959                prefer_ofs_delta = 0;
 960
 961        if (server_supports("filter")) {
 962                server_supports_filtering = 1;
 963                print_verbose(args, _("Server supports %s"), "filter");
 964        } else if (args->filter_options.choice) {
 965                warning("filtering not recognized by server, ignoring");
 966        }
 967
 968        if (server_supports("deepen-since")) {
 969                print_verbose(args, _("Server supports %s"), "deepen-since");
 970                deepen_since_ok = 1;
 971        } else if (args->deepen_since)
 972                die(_("Server does not support --shallow-since"));
 973        if (server_supports("deepen-not")) {
 974                print_verbose(args, _("Server supports %s"), "deepen-not");
 975                deepen_not_ok = 1;
 976        } else if (args->deepen_not)
 977                die(_("Server does not support --shallow-exclude"));
 978        if (server_supports("deepen-relative"))
 979                print_verbose(args, _("Server supports %s"), "deepen-relative");
 980        else if (args->deepen_relative)
 981                die(_("Server does not support --deepen"));
 982
 983        if (!args->no_dependents) {
 984                mark_complete_and_common_ref(&negotiator, args, &ref);
 985                filter_refs(args, &ref, sought, nr_sought);
 986                if (everything_local(args, &ref)) {
 987                        packet_flush(fd[1]);
 988                        goto all_done;
 989                }
 990        } else {
 991                filter_refs(args, &ref, sought, nr_sought);
 992        }
 993        if (find_common(&negotiator, 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        negotiator.release(&negotiator);
1014        return ref;
1015}
1016
1017static void add_shallow_requests(struct strbuf *req_buf,
1018                                 const struct fetch_pack_args *args)
1019{
1020        if (is_repository_shallow(the_repository))
1021                write_shallow_commits(req_buf, 1, NULL);
1022        if (args->depth > 0)
1023                packet_buf_write(req_buf, "deepen %d", args->depth);
1024        if (args->deepen_since) {
1025                timestamp_t max_age = approxidate(args->deepen_since);
1026                packet_buf_write(req_buf, "deepen-since %"PRItime, max_age);
1027        }
1028        if (args->deepen_not) {
1029                int i;
1030                for (i = 0; i < args->deepen_not->nr; i++) {
1031                        struct string_list_item *s = args->deepen_not->items + i;
1032                        packet_buf_write(req_buf, "deepen-not %s", s->string);
1033                }
1034        }
1035        if (args->deepen_relative)
1036                packet_buf_write(req_buf, "deepen-relative\n");
1037}
1038
1039static void add_wants(int no_dependents, const struct ref *wants, struct strbuf *req_buf)
1040{
1041        int use_ref_in_want = server_supports_feature("fetch", "ref-in-want", 0);
1042
1043        for ( ; wants ; wants = wants->next) {
1044                const struct object_id *remote = &wants->old_oid;
1045                struct object *o;
1046
1047                /*
1048                 * If that object is complete (i.e. it is an ancestor of a
1049                 * local ref), we tell them we have it but do not have to
1050                 * tell them about its ancestors, which they already know
1051                 * about.
1052                 *
1053                 * We use lookup_object here because we are only
1054                 * interested in the case we *know* the object is
1055                 * reachable and we have already scanned it.
1056                 *
1057                 * Do this only if args->no_dependents is false (if it is true,
1058                 * we cannot trust the object flags).
1059                 */
1060                if (!no_dependents &&
1061                    ((o = lookup_object(the_repository, remote)) != NULL) &&
1062                    (o->flags & COMPLETE)) {
1063                        continue;
1064                }
1065
1066                if (!use_ref_in_want || wants->exact_oid)
1067                        packet_buf_write(req_buf, "want %s\n", oid_to_hex(remote));
1068                else
1069                        packet_buf_write(req_buf, "want-ref %s\n", wants->name);
1070        }
1071}
1072
1073static void add_common(struct strbuf *req_buf, struct oidset *common)
1074{
1075        struct oidset_iter iter;
1076        const struct object_id *oid;
1077        oidset_iter_init(common, &iter);
1078
1079        while ((oid = oidset_iter_next(&iter))) {
1080                packet_buf_write(req_buf, "have %s\n", oid_to_hex(oid));
1081        }
1082}
1083
1084static int add_haves(struct fetch_negotiator *negotiator,
1085                     struct strbuf *req_buf,
1086                     int *haves_to_send, int *in_vain)
1087{
1088        int ret = 0;
1089        int haves_added = 0;
1090        const struct object_id *oid;
1091
1092        while ((oid = negotiator->next(negotiator))) {
1093                packet_buf_write(req_buf, "have %s\n", oid_to_hex(oid));
1094                if (++haves_added >= *haves_to_send)
1095                        break;
1096        }
1097
1098        *in_vain += haves_added;
1099        if (!haves_added || *in_vain >= MAX_IN_VAIN) {
1100                /* Send Done */
1101                packet_buf_write(req_buf, "done\n");
1102                ret = 1;
1103        }
1104
1105        /* Increase haves to send on next round */
1106        *haves_to_send = next_flush(1, *haves_to_send);
1107
1108        return ret;
1109}
1110
1111static int send_fetch_request(struct fetch_negotiator *negotiator, int fd_out,
1112                              struct fetch_pack_args *args,
1113                              const struct ref *wants, struct oidset *common,
1114                              int *haves_to_send, int *in_vain,
1115                              int sideband_all)
1116{
1117        int ret = 0;
1118        struct strbuf req_buf = STRBUF_INIT;
1119
1120        if (server_supports_v2("fetch", 1))
1121                packet_buf_write(&req_buf, "command=fetch");
1122        if (server_supports_v2("agent", 0))
1123                packet_buf_write(&req_buf, "agent=%s", git_user_agent_sanitized());
1124        if (args->server_options && args->server_options->nr &&
1125            server_supports_v2("server-option", 1)) {
1126                int i;
1127                for (i = 0; i < args->server_options->nr; i++)
1128                        packet_buf_write(&req_buf, "server-option=%s",
1129                                         args->server_options->items[i].string);
1130        }
1131
1132        packet_buf_delim(&req_buf);
1133        if (args->use_thin_pack)
1134                packet_buf_write(&req_buf, "thin-pack");
1135        if (args->no_progress)
1136                packet_buf_write(&req_buf, "no-progress");
1137        if (args->include_tag)
1138                packet_buf_write(&req_buf, "include-tag");
1139        if (prefer_ofs_delta)
1140                packet_buf_write(&req_buf, "ofs-delta");
1141        if (sideband_all)
1142                packet_buf_write(&req_buf, "sideband-all");
1143
1144        /* Add shallow-info and deepen request */
1145        if (server_supports_feature("fetch", "shallow", 0))
1146                add_shallow_requests(&req_buf, args);
1147        else if (is_repository_shallow(the_repository) || args->deepen)
1148                die(_("Server does not support shallow requests"));
1149
1150        /* Add filter */
1151        if (server_supports_feature("fetch", "filter", 0) &&
1152            args->filter_options.choice) {
1153                const char *spec =
1154                        expand_list_objects_filter_spec(&args->filter_options);
1155                print_verbose(args, _("Server supports filter"));
1156                packet_buf_write(&req_buf, "filter %s", spec);
1157        } else if (args->filter_options.choice) {
1158                warning("filtering not recognized by server, ignoring");
1159        }
1160
1161        /* add wants */
1162        add_wants(args->no_dependents, wants, &req_buf);
1163
1164        if (args->no_dependents) {
1165                packet_buf_write(&req_buf, "done");
1166                ret = 1;
1167        } else {
1168                /* Add all of the common commits we've found in previous rounds */
1169                add_common(&req_buf, common);
1170
1171                /* Add initial haves */
1172                ret = add_haves(negotiator, &req_buf, haves_to_send, in_vain);
1173        }
1174
1175        /* Send request */
1176        packet_buf_flush(&req_buf);
1177        if (write_in_full(fd_out, req_buf.buf, req_buf.len) < 0)
1178                die_errno(_("unable to write request to remote"));
1179
1180        strbuf_release(&req_buf);
1181        return ret;
1182}
1183
1184/*
1185 * Processes a section header in a server's response and checks if it matches
1186 * `section`.  If the value of `peek` is 1, the header line will be peeked (and
1187 * not consumed); if 0, the line will be consumed and the function will die if
1188 * the section header doesn't match what was expected.
1189 */
1190static int process_section_header(struct packet_reader *reader,
1191                                  const char *section, int peek)
1192{
1193        int ret;
1194
1195        if (packet_reader_peek(reader) != PACKET_READ_NORMAL)
1196                die(_("error reading section header '%s'"), section);
1197
1198        ret = !strcmp(reader->line, section);
1199
1200        if (!peek) {
1201                if (!ret)
1202                        die(_("expected '%s', received '%s'"),
1203                            section, reader->line);
1204                packet_reader_read(reader);
1205        }
1206
1207        return ret;
1208}
1209
1210static int process_acks(struct fetch_negotiator *negotiator,
1211                        struct packet_reader *reader,
1212                        struct oidset *common)
1213{
1214        /* received */
1215        int received_ready = 0;
1216        int received_ack = 0;
1217
1218        process_section_header(reader, "acknowledgments", 0);
1219        while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
1220                const char *arg;
1221
1222                if (!strcmp(reader->line, "NAK"))
1223                        continue;
1224
1225                if (skip_prefix(reader->line, "ACK ", &arg)) {
1226                        struct object_id oid;
1227                        if (!get_oid_hex(arg, &oid)) {
1228                                struct commit *commit;
1229                                oidset_insert(common, &oid);
1230                                commit = lookup_commit(the_repository, &oid);
1231                                negotiator->ack(negotiator, commit);
1232                        }
1233                        continue;
1234                }
1235
1236                if (!strcmp(reader->line, "ready")) {
1237                        received_ready = 1;
1238                        continue;
1239                }
1240
1241                die(_("unexpected acknowledgment line: '%s'"), reader->line);
1242        }
1243
1244        if (reader->status != PACKET_READ_FLUSH &&
1245            reader->status != PACKET_READ_DELIM)
1246                die(_("error processing acks: %d"), reader->status);
1247
1248        /*
1249         * If an "acknowledgments" section is sent, a packfile is sent if and
1250         * only if "ready" was sent in this section. The other sections
1251         * ("shallow-info" and "wanted-refs") are sent only if a packfile is
1252         * sent. Therefore, a DELIM is expected if "ready" is sent, and a FLUSH
1253         * otherwise.
1254         */
1255        if (received_ready && reader->status != PACKET_READ_DELIM)
1256                die(_("expected packfile to be sent after 'ready'"));
1257        if (!received_ready && reader->status != PACKET_READ_FLUSH)
1258                die(_("expected no other sections to be sent after no 'ready'"));
1259
1260        /* return 0 if no common, 1 if there are common, or 2 if ready */
1261        return received_ready ? 2 : (received_ack ? 1 : 0);
1262}
1263
1264static void receive_shallow_info(struct fetch_pack_args *args,
1265                                 struct packet_reader *reader,
1266                                 struct oid_array *shallows,
1267                                 struct shallow_info *si)
1268{
1269        int unshallow_received = 0;
1270
1271        process_section_header(reader, "shallow-info", 0);
1272        while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
1273                const char *arg;
1274                struct object_id oid;
1275
1276                if (skip_prefix(reader->line, "shallow ", &arg)) {
1277                        if (get_oid_hex(arg, &oid))
1278                                die(_("invalid shallow line: %s"), reader->line);
1279                        oid_array_append(shallows, &oid);
1280                        continue;
1281                }
1282                if (skip_prefix(reader->line, "unshallow ", &arg)) {
1283                        if (get_oid_hex(arg, &oid))
1284                                die(_("invalid unshallow line: %s"), reader->line);
1285                        if (!lookup_object(the_repository, &oid))
1286                                die(_("object not found: %s"), reader->line);
1287                        /* make sure that it is parsed as shallow */
1288                        if (!parse_object(the_repository, &oid))
1289                                die(_("error in object: %s"), reader->line);
1290                        if (unregister_shallow(&oid))
1291                                die(_("no shallow found: %s"), reader->line);
1292                        unshallow_received = 1;
1293                        continue;
1294                }
1295                die(_("expected shallow/unshallow, got %s"), reader->line);
1296        }
1297
1298        if (reader->status != PACKET_READ_FLUSH &&
1299            reader->status != PACKET_READ_DELIM)
1300                die(_("error processing shallow info: %d"), reader->status);
1301
1302        if (args->deepen || unshallow_received) {
1303                /*
1304                 * Treat these as shallow lines caused by our depth settings.
1305                 * In v0, these lines cannot cause refs to be rejected; do the
1306                 * same.
1307                 */
1308                int i;
1309
1310                for (i = 0; i < shallows->nr; i++)
1311                        register_shallow(the_repository, &shallows->oid[i]);
1312                setup_alternate_shallow(&shallow_lock, &alternate_shallow_file,
1313                                        NULL);
1314                args->deepen = 1;
1315        } else if (shallows->nr) {
1316                /*
1317                 * Treat these as shallow lines caused by the remote being
1318                 * shallow. In v0, remote refs that reach these objects are
1319                 * rejected (unless --update-shallow is set); do the same.
1320                 */
1321                prepare_shallow_info(si, shallows);
1322                if (si->nr_ours || si->nr_theirs)
1323                        alternate_shallow_file =
1324                                setup_temporary_shallow(si->shallow);
1325                else
1326                        alternate_shallow_file = NULL;
1327        } else {
1328                alternate_shallow_file = NULL;
1329        }
1330}
1331
1332static int cmp_name_ref(const void *name, const void *ref)
1333{
1334        return strcmp(name, (*(struct ref **)ref)->name);
1335}
1336
1337static void receive_wanted_refs(struct packet_reader *reader,
1338                                struct ref **sought, int nr_sought)
1339{
1340        process_section_header(reader, "wanted-refs", 0);
1341        while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
1342                struct object_id oid;
1343                const char *end;
1344                struct ref **found;
1345
1346                if (parse_oid_hex(reader->line, &oid, &end) || *end++ != ' ')
1347                        die(_("expected wanted-ref, got '%s'"), reader->line);
1348
1349                found = bsearch(end, sought, nr_sought, sizeof(*sought),
1350                                cmp_name_ref);
1351                if (!found)
1352                        die(_("unexpected wanted-ref: '%s'"), reader->line);
1353                oidcpy(&(*found)->old_oid, &oid);
1354        }
1355
1356        if (reader->status != PACKET_READ_DELIM)
1357                die(_("error processing wanted refs: %d"), reader->status);
1358}
1359
1360enum fetch_state {
1361        FETCH_CHECK_LOCAL = 0,
1362        FETCH_SEND_REQUEST,
1363        FETCH_PROCESS_ACKS,
1364        FETCH_GET_PACK,
1365        FETCH_DONE,
1366};
1367
1368static struct ref *do_fetch_pack_v2(struct fetch_pack_args *args,
1369                                    int fd[2],
1370                                    const struct ref *orig_ref,
1371                                    struct ref **sought, int nr_sought,
1372                                    struct oid_array *shallows,
1373                                    struct shallow_info *si,
1374                                    char **pack_lockfile)
1375{
1376        struct repository *r = the_repository;
1377        struct ref *ref = copy_ref_list(orig_ref);
1378        enum fetch_state state = FETCH_CHECK_LOCAL;
1379        struct oidset common = OIDSET_INIT;
1380        struct packet_reader reader;
1381        int in_vain = 0;
1382        int haves_to_send = INITIAL_FLUSH;
1383        struct fetch_negotiator negotiator;
1384        fetch_negotiator_init(r, &negotiator);
1385        packet_reader_init(&reader, fd[0], NULL, 0,
1386                           PACKET_READ_CHOMP_NEWLINE |
1387                           PACKET_READ_DIE_ON_ERR_PACKET);
1388        if (git_env_bool("GIT_TEST_SIDEBAND_ALL", 1) &&
1389            server_supports_feature("fetch", "sideband-all", 0)) {
1390                reader.use_sideband = 1;
1391                reader.me = "fetch-pack";
1392        }
1393
1394        while (state != FETCH_DONE) {
1395                switch (state) {
1396                case FETCH_CHECK_LOCAL:
1397                        sort_ref_list(&ref, ref_compare_name);
1398                        QSORT(sought, nr_sought, cmp_ref_by_name);
1399
1400                        /* v2 supports these by default */
1401                        allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
1402                        use_sideband = 2;
1403                        if (args->depth > 0 || args->deepen_since || args->deepen_not)
1404                                args->deepen = 1;
1405
1406                        /* Filter 'ref' by 'sought' and those that aren't local */
1407                        if (!args->no_dependents) {
1408                                mark_complete_and_common_ref(&negotiator, args, &ref);
1409                                filter_refs(args, &ref, sought, nr_sought);
1410                                if (everything_local(args, &ref))
1411                                        state = FETCH_DONE;
1412                                else
1413                                        state = FETCH_SEND_REQUEST;
1414
1415                                mark_tips(&negotiator, args->negotiation_tips);
1416                                for_each_cached_alternate(&negotiator,
1417                                                          insert_one_alternate_object);
1418                        } else {
1419                                filter_refs(args, &ref, sought, nr_sought);
1420                                state = FETCH_SEND_REQUEST;
1421                        }
1422                        break;
1423                case FETCH_SEND_REQUEST:
1424                        if (send_fetch_request(&negotiator, fd[1], args, ref,
1425                                               &common,
1426                                               &haves_to_send, &in_vain,
1427                                               reader.use_sideband))
1428                                state = FETCH_GET_PACK;
1429                        else
1430                                state = FETCH_PROCESS_ACKS;
1431                        break;
1432                case FETCH_PROCESS_ACKS:
1433                        /* Process ACKs/NAKs */
1434                        switch (process_acks(&negotiator, &reader, &common)) {
1435                        case 2:
1436                                state = FETCH_GET_PACK;
1437                                break;
1438                        case 1:
1439                                in_vain = 0;
1440                                /* fallthrough */
1441                        default:
1442                                state = FETCH_SEND_REQUEST;
1443                                break;
1444                        }
1445                        break;
1446                case FETCH_GET_PACK:
1447                        /* Check for shallow-info section */
1448                        if (process_section_header(&reader, "shallow-info", 1))
1449                                receive_shallow_info(args, &reader, shallows, si);
1450
1451                        if (process_section_header(&reader, "wanted-refs", 1))
1452                                receive_wanted_refs(&reader, sought, nr_sought);
1453
1454                        /* get the pack */
1455                        process_section_header(&reader, "packfile", 0);
1456                        if (get_pack(args, fd, pack_lockfile))
1457                                die(_("git fetch-pack: fetch failed."));
1458
1459                        state = FETCH_DONE;
1460                        break;
1461                case FETCH_DONE:
1462                        continue;
1463                }
1464        }
1465
1466        negotiator.release(&negotiator);
1467        oidset_clear(&common);
1468        return ref;
1469}
1470
1471static int fetch_pack_config_cb(const char *var, const char *value, void *cb)
1472{
1473        if (strcmp(var, "fetch.fsck.skiplist") == 0) {
1474                const char *path;
1475
1476                if (git_config_pathname(&path, var, value))
1477                        return 1;
1478                strbuf_addf(&fsck_msg_types, "%cskiplist=%s",
1479                        fsck_msg_types.len ? ',' : '=', path);
1480                free((char *)path);
1481                return 0;
1482        }
1483
1484        if (skip_prefix(var, "fetch.fsck.", &var)) {
1485                if (is_valid_msg_type(var, value))
1486                        strbuf_addf(&fsck_msg_types, "%c%s=%s",
1487                                fsck_msg_types.len ? ',' : '=', var, value);
1488                else
1489                        warning("Skipping unknown msg id '%s'", var);
1490                return 0;
1491        }
1492
1493        return git_default_config(var, value, cb);
1494}
1495
1496static void fetch_pack_config(void)
1497{
1498        git_config_get_int("fetch.unpacklimit", &fetch_unpack_limit);
1499        git_config_get_int("transfer.unpacklimit", &transfer_unpack_limit);
1500        git_config_get_bool("repack.usedeltabaseoffset", &prefer_ofs_delta);
1501        git_config_get_bool("fetch.fsckobjects", &fetch_fsck_objects);
1502        git_config_get_bool("transfer.fsckobjects", &transfer_fsck_objects);
1503
1504        git_config(fetch_pack_config_cb, NULL);
1505}
1506
1507static void fetch_pack_setup(void)
1508{
1509        static int did_setup;
1510        if (did_setup)
1511                return;
1512        fetch_pack_config();
1513        if (0 <= transfer_unpack_limit)
1514                unpack_limit = transfer_unpack_limit;
1515        else if (0 <= fetch_unpack_limit)
1516                unpack_limit = fetch_unpack_limit;
1517        did_setup = 1;
1518}
1519
1520static int remove_duplicates_in_refs(struct ref **ref, int nr)
1521{
1522        struct string_list names = STRING_LIST_INIT_NODUP;
1523        int src, dst;
1524
1525        for (src = dst = 0; src < nr; src++) {
1526                struct string_list_item *item;
1527                item = string_list_insert(&names, ref[src]->name);
1528                if (item->util)
1529                        continue; /* already have it */
1530                item->util = ref[src];
1531                if (src != dst)
1532                        ref[dst] = ref[src];
1533                dst++;
1534        }
1535        for (src = dst; src < nr; src++)
1536                ref[src] = NULL;
1537        string_list_clear(&names, 0);
1538        return dst;
1539}
1540
1541static void update_shallow(struct fetch_pack_args *args,
1542                           struct ref **sought, int nr_sought,
1543                           struct shallow_info *si)
1544{
1545        struct oid_array ref = OID_ARRAY_INIT;
1546        int *status;
1547        int i;
1548
1549        if (args->deepen && alternate_shallow_file) {
1550                if (*alternate_shallow_file == '\0') { /* --unshallow */
1551                        unlink_or_warn(git_path_shallow(the_repository));
1552                        rollback_lock_file(&shallow_lock);
1553                } else
1554                        commit_lock_file(&shallow_lock);
1555                alternate_shallow_file = NULL;
1556                return;
1557        }
1558
1559        if (!si->shallow || !si->shallow->nr)
1560                return;
1561
1562        if (args->cloning) {
1563                /*
1564                 * remote is shallow, but this is a clone, there are
1565                 * no objects in repo to worry about. Accept any
1566                 * shallow points that exist in the pack (iow in repo
1567                 * after get_pack() and reprepare_packed_git())
1568                 */
1569                struct oid_array extra = OID_ARRAY_INIT;
1570                struct object_id *oid = si->shallow->oid;
1571                for (i = 0; i < si->shallow->nr; i++)
1572                        if (has_object_file(&oid[i]))
1573                                oid_array_append(&extra, &oid[i]);
1574                if (extra.nr) {
1575                        setup_alternate_shallow(&shallow_lock,
1576                                                &alternate_shallow_file,
1577                                                &extra);
1578                        commit_lock_file(&shallow_lock);
1579                        alternate_shallow_file = NULL;
1580                }
1581                oid_array_clear(&extra);
1582                return;
1583        }
1584
1585        if (!si->nr_ours && !si->nr_theirs)
1586                return;
1587
1588        remove_nonexistent_theirs_shallow(si);
1589        if (!si->nr_ours && !si->nr_theirs)
1590                return;
1591        for (i = 0; i < nr_sought; i++)
1592                oid_array_append(&ref, &sought[i]->old_oid);
1593        si->ref = &ref;
1594
1595        if (args->update_shallow) {
1596                /*
1597                 * remote is also shallow, .git/shallow may be updated
1598                 * so all refs can be accepted. Make sure we only add
1599                 * shallow roots that are actually reachable from new
1600                 * refs.
1601                 */
1602                struct oid_array extra = OID_ARRAY_INIT;
1603                struct object_id *oid = si->shallow->oid;
1604                assign_shallow_commits_to_refs(si, NULL, NULL);
1605                if (!si->nr_ours && !si->nr_theirs) {
1606                        oid_array_clear(&ref);
1607                        return;
1608                }
1609                for (i = 0; i < si->nr_ours; i++)
1610                        oid_array_append(&extra, &oid[si->ours[i]]);
1611                for (i = 0; i < si->nr_theirs; i++)
1612                        oid_array_append(&extra, &oid[si->theirs[i]]);
1613                setup_alternate_shallow(&shallow_lock,
1614                                        &alternate_shallow_file,
1615                                        &extra);
1616                commit_lock_file(&shallow_lock);
1617                oid_array_clear(&extra);
1618                oid_array_clear(&ref);
1619                alternate_shallow_file = NULL;
1620                return;
1621        }
1622
1623        /*
1624         * remote is also shallow, check what ref is safe to update
1625         * without updating .git/shallow
1626         */
1627        status = xcalloc(nr_sought, sizeof(*status));
1628        assign_shallow_commits_to_refs(si, NULL, status);
1629        if (si->nr_ours || si->nr_theirs) {
1630                for (i = 0; i < nr_sought; i++)
1631                        if (status[i])
1632                                sought[i]->status = REF_STATUS_REJECT_SHALLOW;
1633        }
1634        free(status);
1635        oid_array_clear(&ref);
1636}
1637
1638static int iterate_ref_map(void *cb_data, struct object_id *oid)
1639{
1640        struct ref **rm = cb_data;
1641        struct ref *ref = *rm;
1642
1643        if (!ref)
1644                return -1; /* end of the list */
1645        *rm = ref->next;
1646        oidcpy(oid, &ref->old_oid);
1647        return 0;
1648}
1649
1650struct ref *fetch_pack(struct fetch_pack_args *args,
1651                       int fd[],
1652                       const struct ref *ref,
1653                       struct ref **sought, int nr_sought,
1654                       struct oid_array *shallow,
1655                       char **pack_lockfile,
1656                       enum protocol_version version)
1657{
1658        struct ref *ref_cpy;
1659        struct shallow_info si;
1660        struct oid_array shallows_scratch = OID_ARRAY_INIT;
1661
1662        fetch_pack_setup();
1663        if (nr_sought)
1664                nr_sought = remove_duplicates_in_refs(sought, nr_sought);
1665
1666        if (args->no_dependents && !args->filter_options.choice) {
1667                /*
1668                 * The protocol does not support requesting that only the
1669                 * wanted objects be sent, so approximate this by setting a
1670                 * "blob:none" filter if no filter is already set. This works
1671                 * for all object types: note that wanted blobs will still be
1672                 * sent because they are directly specified as a "want".
1673                 *
1674                 * NEEDSWORK: Add an option in the protocol to request that
1675                 * only the wanted objects be sent, and implement it.
1676                 */
1677                parse_list_objects_filter(&args->filter_options, "blob:none");
1678        }
1679
1680        if (version != protocol_v2 && !ref) {
1681                packet_flush(fd[1]);
1682                die(_("no matching remote head"));
1683        }
1684        if (version == protocol_v2) {
1685                if (shallow->nr)
1686                        BUG("Protocol V2 does not provide shallows at this point in the fetch");
1687                memset(&si, 0, sizeof(si));
1688                ref_cpy = do_fetch_pack_v2(args, fd, ref, sought, nr_sought,
1689                                           &shallows_scratch, &si,
1690                                           pack_lockfile);
1691        } else {
1692                prepare_shallow_info(&si, shallow);
1693                ref_cpy = do_fetch_pack(args, fd, ref, sought, nr_sought,
1694                                        &si, pack_lockfile);
1695        }
1696        reprepare_packed_git(the_repository);
1697
1698        if (!args->cloning && args->deepen) {
1699                struct check_connected_options opt = CHECK_CONNECTED_INIT;
1700                struct ref *iterator = ref_cpy;
1701                opt.shallow_file = alternate_shallow_file;
1702                if (args->deepen)
1703                        opt.is_deepening_fetch = 1;
1704                if (check_connected(iterate_ref_map, &iterator, &opt)) {
1705                        error(_("remote did not send all necessary objects"));
1706                        free_refs(ref_cpy);
1707                        ref_cpy = NULL;
1708                        rollback_lock_file(&shallow_lock);
1709                        goto cleanup;
1710                }
1711                args->connectivity_checked = 1;
1712        }
1713
1714        update_shallow(args, sought, nr_sought, &si);
1715cleanup:
1716        clear_shallow_info(&si);
1717        oid_array_clear(&shallows_scratch);
1718        return ref_cpy;
1719}
1720
1721int report_unmatched_refs(struct ref **sought, int nr_sought)
1722{
1723        int i, ret = 0;
1724
1725        for (i = 0; i < nr_sought; i++) {
1726                if (!sought[i])
1727                        continue;
1728                switch (sought[i]->match_status) {
1729                case REF_MATCHED:
1730                        continue;
1731                case REF_NOT_MATCHED:
1732                        error(_("no such remote ref %s"), sought[i]->name);
1733                        break;
1734                case REF_UNADVERTISED_NOT_ALLOWED:
1735                        error(_("Server does not allow request for unadvertised object %s"),
1736                              sought[i]->name);
1737                        break;
1738                }
1739                ret = 1;
1740        }
1741        return ret;
1742}