fetch-pack.con commit Merge branch 'pw/diff-color-moved-ws-fix' (2916cfe)
   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 char *negotiation_algorithm;
  40static struct strbuf fsck_msg_types = STRBUF_INIT;
  41
  42/* Remember to update object flag allocation in object.h */
  43#define COMPLETE        (1U << 0)
  44#define ALTERNATE       (1U << 1)
  45
  46/*
  47 * After sending this many "have"s if we do not get any new ACK , we
  48 * give up traversing our history.
  49 */
  50#define MAX_IN_VAIN 256
  51
  52static int 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
  57static unsigned int allow_unadvertised_object_request;
  58
  59__attribute__((format (printf, 2, 3)))
  60static 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
  74struct alternate_object_cache {
  75        struct object **items;
  76        size_t nr, alloc;
  77};
  78
  79static 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(the_repository, 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
  94static void for_each_cached_alternate(struct fetch_negotiator *negotiator,
  95                                      void (*cb)(struct fetch_negotiator *,
  96                                                 struct object *))
  97{
  98        static int initialized;
  99        static struct alternate_object_cache cache;
 100        size_t i;
 101
 102        if (!initialized) {
 103                for_each_alternate_ref(cache_one_alternate, &cache);
 104                initialized = 1;
 105        }
 106
 107        for (i = 0; i < cache.nr; i++)
 108                cb(negotiator, cache.items[i]);
 109}
 110
 111static int rev_list_insert_ref(struct fetch_negotiator *negotiator,
 112                               const char *refname,
 113                               const struct object_id *oid)
 114{
 115        struct object *o = deref_tag(the_repository,
 116                                     parse_object(the_repository, oid),
 117                                     refname, 0);
 118
 119        if (o && o->type == OBJ_COMMIT)
 120                negotiator->add_tip(negotiator, (struct commit *)o);
 121
 122        return 0;
 123}
 124
 125static int rev_list_insert_ref_oid(const char *refname, const struct object_id *oid,
 126                                   int flag, void *cb_data)
 127{
 128        return rev_list_insert_ref(cb_data, refname, oid);
 129}
 130
 131enum ack_type {
 132        NAK = 0,
 133        ACK,
 134        ACK_continue,
 135        ACK_common,
 136        ACK_ready
 137};
 138
 139static void consume_shallow_list(struct fetch_pack_args *args, int fd)
 140{
 141        if (args->stateless_rpc && args->deepen) {
 142                /* If we sent a depth we will get back "duplicate"
 143                 * shallow and unshallow commands every time there
 144                 * is a block of have lines exchanged.
 145                 */
 146                char *line;
 147                while ((line = packet_read_line(fd, NULL))) {
 148                        if (starts_with(line, "shallow "))
 149                                continue;
 150                        if (starts_with(line, "unshallow "))
 151                                continue;
 152                        die(_("git fetch-pack: expected shallow list"));
 153                }
 154        }
 155}
 156
 157static enum ack_type get_ack(int fd, struct object_id *result_oid)
 158{
 159        int len;
 160        char *line = packet_read_line(fd, &len);
 161        const char *arg;
 162
 163        if (!line)
 164                die(_("git fetch-pack: expected ACK/NAK, got a flush packet"));
 165        if (!strcmp(line, "NAK"))
 166                return NAK;
 167        if (skip_prefix(line, "ACK ", &arg)) {
 168                if (!get_oid_hex(arg, result_oid)) {
 169                        arg += 40;
 170                        len -= arg - line;
 171                        if (len < 1)
 172                                return ACK;
 173                        if (strstr(arg, "continue"))
 174                                return ACK_continue;
 175                        if (strstr(arg, "common"))
 176                                return ACK_common;
 177                        if (strstr(arg, "ready"))
 178                                return ACK_ready;
 179                        return ACK;
 180                }
 181        }
 182        if (skip_prefix(line, "ERR ", &arg))
 183                die(_("remote error: %s"), arg);
 184        die(_("git fetch-pack: expected ACK/NAK, got '%s'"), 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                write_or_die(fd, buf->buf, buf->len);
 195}
 196
 197static void insert_one_alternate_object(struct fetch_negotiator *negotiator,
 198                                        struct object *obj)
 199{
 200        rev_list_insert_ref(negotiator, NULL, &obj->oid);
 201}
 202
 203#define INITIAL_FLUSH 16
 204#define PIPESAFE_FLUSH 32
 205#define LARGE_FLUSH 16384
 206
 207static int next_flush(int stateless_rpc, int count)
 208{
 209        if (stateless_rpc) {
 210                if (count < LARGE_FLUSH)
 211                        count <<= 1;
 212                else
 213                        count = count * 11 / 10;
 214        } else {
 215                if (count < PIPESAFE_FLUSH)
 216                        count <<= 1;
 217                else
 218                        count += PIPESAFE_FLUSH;
 219        }
 220        return count;
 221}
 222
 223static void mark_tips(struct fetch_negotiator *negotiator,
 224                      const struct oid_array *negotiation_tips)
 225{
 226        int i;
 227
 228        if (!negotiation_tips) {
 229                for_each_ref(rev_list_insert_ref_oid, negotiator);
 230                return;
 231        }
 232
 233        for (i = 0; i < negotiation_tips->nr; i++)
 234                rev_list_insert_ref(negotiator, NULL,
 235                                    &negotiation_tips->oid[i]);
 236        return;
 237}
 238
 239static int find_common(struct fetch_negotiator *negotiator,
 240                       struct fetch_pack_args *args,
 241                       int fd[2], struct object_id *result_oid,
 242                       struct ref *refs)
 243{
 244        int fetching;
 245        int count = 0, flushes = 0, flush_at = INITIAL_FLUSH, retval;
 246        const struct object_id *oid;
 247        unsigned in_vain = 0;
 248        int got_continue = 0;
 249        int got_ready = 0;
 250        struct strbuf req_buf = STRBUF_INIT;
 251        size_t state_len = 0;
 252
 253        if (args->stateless_rpc && multi_ack == 1)
 254                die(_("--stateless-rpc requires multi_ack_detailed"));
 255
 256        mark_tips(negotiator, args->negotiation_tips);
 257        for_each_cached_alternate(negotiator, insert_one_alternate_object);
 258
 259        fetching = 0;
 260        for ( ; refs ; refs = refs->next) {
 261                struct object_id *remote = &refs->old_oid;
 262                const char *remote_hex;
 263                struct object *o;
 264
 265                /*
 266                 * If that object is complete (i.e. it is an ancestor of a
 267                 * local ref), we tell them we have it but do not have to
 268                 * tell them about its ancestors, which they already know
 269                 * about.
 270                 *
 271                 * We use lookup_object here because we are only
 272                 * interested in the case we *know* the object is
 273                 * reachable and we have already scanned it.
 274                 */
 275                if (((o = lookup_object(the_repository, remote->hash)) != NULL) &&
 276                                (o->flags & COMPLETE)) {
 277                        continue;
 278                }
 279
 280                remote_hex = oid_to_hex(remote);
 281                if (!fetching) {
 282                        struct strbuf c = STRBUF_INIT;
 283                        if (multi_ack == 2)     strbuf_addstr(&c, " multi_ack_detailed");
 284                        if (multi_ack == 1)     strbuf_addstr(&c, " multi_ack");
 285                        if (no_done)            strbuf_addstr(&c, " no-done");
 286                        if (use_sideband == 2)  strbuf_addstr(&c, " side-band-64k");
 287                        if (use_sideband == 1)  strbuf_addstr(&c, " side-band");
 288                        if (args->deepen_relative) strbuf_addstr(&c, " deepen-relative");
 289                        if (args->use_thin_pack) strbuf_addstr(&c, " thin-pack");
 290                        if (args->no_progress)   strbuf_addstr(&c, " no-progress");
 291                        if (args->include_tag)   strbuf_addstr(&c, " include-tag");
 292                        if (prefer_ofs_delta)   strbuf_addstr(&c, " ofs-delta");
 293                        if (deepen_since_ok)    strbuf_addstr(&c, " deepen-since");
 294                        if (deepen_not_ok)      strbuf_addstr(&c, " deepen-not");
 295                        if (agent_supported)    strbuf_addf(&c, " agent=%s",
 296                                                            git_user_agent_sanitized());
 297                        if (args->filter_options.choice)
 298                                strbuf_addstr(&c, " filter");
 299                        packet_buf_write(&req_buf, "want %s%s\n", remote_hex, c.buf);
 300                        strbuf_release(&c);
 301                } else
 302                        packet_buf_write(&req_buf, "want %s\n", remote_hex);
 303                fetching++;
 304        }
 305
 306        if (!fetching) {
 307                strbuf_release(&req_buf);
 308                packet_flush(fd[1]);
 309                return 1;
 310        }
 311
 312        if (is_repository_shallow(the_repository))
 313                write_shallow_commits(&req_buf, 1, NULL);
 314        if (args->depth > 0)
 315                packet_buf_write(&req_buf, "deepen %d", args->depth);
 316        if (args->deepen_since) {
 317                timestamp_t max_age = approxidate(args->deepen_since);
 318                packet_buf_write(&req_buf, "deepen-since %"PRItime, max_age);
 319        }
 320        if (args->deepen_not) {
 321                int i;
 322                for (i = 0; i < args->deepen_not->nr; i++) {
 323                        struct string_list_item *s = args->deepen_not->items + i;
 324                        packet_buf_write(&req_buf, "deepen-not %s", s->string);
 325                }
 326        }
 327        if (server_supports_filtering && args->filter_options.choice)
 328                packet_buf_write(&req_buf, "filter %s",
 329                                 args->filter_options.filter_spec);
 330        packet_buf_flush(&req_buf);
 331        state_len = req_buf.len;
 332
 333        if (args->deepen) {
 334                char *line;
 335                const char *arg;
 336                struct object_id oid;
 337
 338                send_request(args, fd[1], &req_buf);
 339                while ((line = packet_read_line(fd[0], NULL))) {
 340                        if (skip_prefix(line, "shallow ", &arg)) {
 341                                if (get_oid_hex(arg, &oid))
 342                                        die(_("invalid shallow line: %s"), line);
 343                                register_shallow(the_repository, &oid);
 344                                continue;
 345                        }
 346                        if (skip_prefix(line, "unshallow ", &arg)) {
 347                                if (get_oid_hex(arg, &oid))
 348                                        die(_("invalid unshallow line: %s"), line);
 349                                if (!lookup_object(the_repository, oid.hash))
 350                                        die(_("object not found: %s"), line);
 351                                /* make sure that it is parsed as shallow */
 352                                if (!parse_object(the_repository, &oid))
 353                                        die(_("error in object: %s"), line);
 354                                if (unregister_shallow(&oid))
 355                                        die(_("no shallow found: %s"), line);
 356                                continue;
 357                        }
 358                        die(_("expected shallow/unshallow, got %s"), line);
 359                }
 360        } else if (!args->stateless_rpc)
 361                send_request(args, fd[1], &req_buf);
 362
 363        if (!args->stateless_rpc) {
 364                /* If we aren't using the stateless-rpc interface
 365                 * we don't need to retain the headers.
 366                 */
 367                strbuf_setlen(&req_buf, 0);
 368                state_len = 0;
 369        }
 370
 371        flushes = 0;
 372        retval = -1;
 373        if (args->no_dependents)
 374                goto done;
 375        while ((oid = negotiator->next(negotiator))) {
 376                packet_buf_write(&req_buf, "have %s\n", oid_to_hex(oid));
 377                print_verbose(args, "have %s", oid_to_hex(oid));
 378                in_vain++;
 379                if (flush_at <= ++count) {
 380                        int ack;
 381
 382                        packet_buf_flush(&req_buf);
 383                        send_request(args, fd[1], &req_buf);
 384                        strbuf_setlen(&req_buf, state_len);
 385                        flushes++;
 386                        flush_at = next_flush(args->stateless_rpc, count);
 387
 388                        /*
 389                         * We keep one window "ahead" of the other side, and
 390                         * will wait for an ACK only on the next one
 391                         */
 392                        if (!args->stateless_rpc && count == INITIAL_FLUSH)
 393                                continue;
 394
 395                        consume_shallow_list(args, fd[0]);
 396                        do {
 397                                ack = get_ack(fd[0], result_oid);
 398                                if (ack)
 399                                        print_verbose(args, _("got %s %d %s"), "ack",
 400                                                      ack, oid_to_hex(result_oid));
 401                                switch (ack) {
 402                                case ACK:
 403                                        flushes = 0;
 404                                        multi_ack = 0;
 405                                        retval = 0;
 406                                        goto done;
 407                                case ACK_common:
 408                                case ACK_ready:
 409                                case ACK_continue: {
 410                                        struct commit *commit =
 411                                                lookup_commit(the_repository,
 412                                                              result_oid);
 413                                        int was_common;
 414
 415                                        if (!commit)
 416                                                die(_("invalid commit %s"), oid_to_hex(result_oid));
 417                                        was_common = negotiator->ack(negotiator, commit);
 418                                        if (args->stateless_rpc
 419                                         && ack == ACK_common
 420                                         && !was_common) {
 421                                                /* We need to replay the have for this object
 422                                                 * on the next RPC request so the peer knows
 423                                                 * it is in common with us.
 424                                                 */
 425                                                const char *hex = oid_to_hex(result_oid);
 426                                                packet_buf_write(&req_buf, "have %s\n", hex);
 427                                                state_len = req_buf.len;
 428                                                /*
 429                                                 * Reset in_vain because an ack
 430                                                 * for this commit has not been
 431                                                 * seen.
 432                                                 */
 433                                                in_vain = 0;
 434                                        } else if (!args->stateless_rpc
 435                                                   || ack != ACK_common)
 436                                                in_vain = 0;
 437                                        retval = 0;
 438                                        got_continue = 1;
 439                                        if (ack == ACK_ready)
 440                                                got_ready = 1;
 441                                        break;
 442                                        }
 443                                }
 444                        } while (ack);
 445                        flushes--;
 446                        if (got_continue && MAX_IN_VAIN < in_vain) {
 447                                print_verbose(args, _("giving up"));
 448                                break; /* give up */
 449                        }
 450                        if (got_ready)
 451                                break;
 452                }
 453        }
 454done:
 455        if (!got_ready || !no_done) {
 456                packet_buf_write(&req_buf, "done\n");
 457                send_request(args, fd[1], &req_buf);
 458        }
 459        print_verbose(args, _("done"));
 460        if (retval != 0) {
 461                multi_ack = 0;
 462                flushes++;
 463        }
 464        strbuf_release(&req_buf);
 465
 466        if (!got_ready || !no_done)
 467                consume_shallow_list(args, fd[0]);
 468        while (flushes || multi_ack) {
 469                int ack = get_ack(fd[0], result_oid);
 470                if (ack) {
 471                        print_verbose(args, _("got %s (%d) %s"), "ack",
 472                                      ack, oid_to_hex(result_oid));
 473                        if (ack == ACK)
 474                                return 0;
 475                        multi_ack = 1;
 476                        continue;
 477                }
 478                flushes--;
 479        }
 480        /* it is no error to fetch into a completely empty repo */
 481        return count ? retval : 0;
 482}
 483
 484static struct commit_list *complete;
 485
 486static int mark_complete(const struct object_id *oid)
 487{
 488        struct object *o = parse_object(the_repository, oid);
 489
 490        while (o && o->type == OBJ_TAG) {
 491                struct tag *t = (struct tag *) o;
 492                if (!t->tagged)
 493                        break; /* broken repository */
 494                o->flags |= COMPLETE;
 495                o = parse_object(the_repository, &t->tagged->oid);
 496        }
 497        if (o && o->type == OBJ_COMMIT) {
 498                struct commit *commit = (struct commit *)o;
 499                if (!(commit->object.flags & COMPLETE)) {
 500                        commit->object.flags |= COMPLETE;
 501                        commit_list_insert(commit, &complete);
 502                }
 503        }
 504        return 0;
 505}
 506
 507static int mark_complete_oid(const char *refname, const struct object_id *oid,
 508                             int flag, void *cb_data)
 509{
 510        return mark_complete(oid);
 511}
 512
 513static void mark_recent_complete_commits(struct fetch_pack_args *args,
 514                                         timestamp_t cutoff)
 515{
 516        while (complete && cutoff <= complete->item->date) {
 517                print_verbose(args, _("Marking %s as complete"),
 518                              oid_to_hex(&complete->item->object.oid));
 519                pop_most_recent_commit(&complete, COMPLETE);
 520        }
 521}
 522
 523static void add_refs_to_oidset(struct oidset *oids, struct ref *refs)
 524{
 525        for (; refs; refs = refs->next)
 526                oidset_insert(oids, &refs->old_oid);
 527}
 528
 529static int is_unmatched_ref(const struct ref *ref)
 530{
 531        struct object_id oid;
 532        const char *p;
 533        return  ref->match_status == REF_NOT_MATCHED &&
 534                !parse_oid_hex(ref->name, &oid, &p) &&
 535                *p == '\0' &&
 536                oideq(&oid, &ref->old_oid);
 537}
 538
 539static void filter_refs(struct fetch_pack_args *args,
 540                        struct ref **refs,
 541                        struct ref **sought, int nr_sought)
 542{
 543        struct ref *newlist = NULL;
 544        struct ref **newtail = &newlist;
 545        struct ref *unmatched = NULL;
 546        struct ref *ref, *next;
 547        struct oidset tip_oids = OIDSET_INIT;
 548        int i;
 549        int strict = !(allow_unadvertised_object_request &
 550                       (ALLOW_TIP_SHA1 | ALLOW_REACHABLE_SHA1));
 551
 552        i = 0;
 553        for (ref = *refs; ref; ref = next) {
 554                int keep = 0;
 555                next = ref->next;
 556
 557                if (starts_with(ref->name, "refs/") &&
 558                    check_refname_format(ref->name, 0))
 559                        ; /* trash */
 560                else {
 561                        while (i < nr_sought) {
 562                                int cmp = strcmp(ref->name, sought[i]->name);
 563                                if (cmp < 0)
 564                                        break; /* definitely do not have it */
 565                                else if (cmp == 0) {
 566                                        keep = 1; /* definitely have it */
 567                                        sought[i]->match_status = REF_MATCHED;
 568                                }
 569                                i++;
 570                        }
 571
 572                        if (!keep && args->fetch_all &&
 573                            (!args->deepen || !starts_with(ref->name, "refs/tags/")))
 574                                keep = 1;
 575                }
 576
 577                if (keep) {
 578                        *newtail = ref;
 579                        ref->next = NULL;
 580                        newtail = &ref->next;
 581                } else {
 582                        ref->next = unmatched;
 583                        unmatched = ref;
 584                }
 585        }
 586
 587        if (strict) {
 588                for (i = 0; i < nr_sought; i++) {
 589                        ref = sought[i];
 590                        if (!is_unmatched_ref(ref))
 591                                continue;
 592
 593                        add_refs_to_oidset(&tip_oids, unmatched);
 594                        add_refs_to_oidset(&tip_oids, newlist);
 595                        break;
 596                }
 597        }
 598
 599        /* Append unmatched requests to the list */
 600        for (i = 0; i < nr_sought; i++) {
 601                ref = sought[i];
 602                if (!is_unmatched_ref(ref))
 603                        continue;
 604
 605                if (!strict || oidset_contains(&tip_oids, &ref->old_oid)) {
 606                        ref->match_status = REF_MATCHED;
 607                        *newtail = copy_ref(ref);
 608                        newtail = &(*newtail)->next;
 609                } else {
 610                        ref->match_status = REF_UNADVERTISED_NOT_ALLOWED;
 611                }
 612        }
 613
 614        oidset_clear(&tip_oids);
 615        for (ref = unmatched; ref; ref = next) {
 616                next = ref->next;
 617                free(ref);
 618        }
 619
 620        *refs = newlist;
 621}
 622
 623static void mark_alternate_complete(struct fetch_negotiator *unused,
 624                                    struct object *obj)
 625{
 626        mark_complete(&obj->oid);
 627}
 628
 629struct loose_object_iter {
 630        struct oidset *loose_object_set;
 631        struct ref *refs;
 632};
 633
 634/*
 635 *  If the number of refs is not larger than the number of loose objects,
 636 *  this function stops inserting.
 637 */
 638static int add_loose_objects_to_set(const struct object_id *oid,
 639                                    const char *path,
 640                                    void *data)
 641{
 642        struct loose_object_iter *iter = data;
 643        oidset_insert(iter->loose_object_set, oid);
 644        if (iter->refs == NULL)
 645                return 1;
 646
 647        iter->refs = iter->refs->next;
 648        return 0;
 649}
 650
 651/*
 652 * Mark recent commits available locally and reachable from a local ref as
 653 * COMPLETE. If args->no_dependents is false, also mark COMPLETE remote refs as
 654 * COMMON_REF (otherwise, we are not planning to participate in negotiation, and
 655 * thus do not need COMMON_REF marks).
 656 *
 657 * The cutoff time for recency is determined by this heuristic: it is the
 658 * earliest commit time of the objects in refs that are commits and that we know
 659 * the commit time of.
 660 */
 661static void mark_complete_and_common_ref(struct fetch_negotiator *negotiator,
 662                                         struct fetch_pack_args *args,
 663                                         struct ref **refs)
 664{
 665        struct ref *ref;
 666        int old_save_commit_buffer = save_commit_buffer;
 667        timestamp_t cutoff = 0;
 668        struct oidset loose_oid_set = OIDSET_INIT;
 669        int use_oidset = 0;
 670        struct loose_object_iter iter = {&loose_oid_set, *refs};
 671
 672        /* Enumerate all loose objects or know refs are not so many. */
 673        use_oidset = !for_each_loose_object(add_loose_objects_to_set,
 674                                            &iter, 0);
 675
 676        save_commit_buffer = 0;
 677
 678        for (ref = *refs; ref; ref = ref->next) {
 679                struct object *o;
 680                unsigned int flags = OBJECT_INFO_QUICK;
 681
 682                if (use_oidset &&
 683                    !oidset_contains(&loose_oid_set, &ref->old_oid)) {
 684                        /*
 685                         * I know this does not exist in the loose form,
 686                         * so check if it exists in a non-loose form.
 687                         */
 688                        flags |= OBJECT_INFO_IGNORE_LOOSE;
 689                }
 690
 691                if (!has_object_file_with_flags(&ref->old_oid, flags))
 692                        continue;
 693                o = parse_object(the_repository, &ref->old_oid);
 694                if (!o)
 695                        continue;
 696
 697                /* We already have it -- which may mean that we were
 698                 * in sync with the other side at some time after
 699                 * that (it is OK if we guess wrong here).
 700                 */
 701                if (o->type == OBJ_COMMIT) {
 702                        struct commit *commit = (struct commit *)o;
 703                        if (!cutoff || cutoff < commit->date)
 704                                cutoff = commit->date;
 705                }
 706        }
 707
 708        oidset_clear(&loose_oid_set);
 709
 710        if (!args->no_dependents) {
 711                if (!args->deepen) {
 712                        for_each_ref(mark_complete_oid, NULL);
 713                        for_each_cached_alternate(NULL, mark_alternate_complete);
 714                        commit_list_sort_by_date(&complete);
 715                        if (cutoff)
 716                                mark_recent_complete_commits(args, cutoff);
 717                }
 718
 719                /*
 720                 * Mark all complete remote refs as common refs.
 721                 * Don't mark them common yet; the server has to be told so first.
 722                 */
 723                for (ref = *refs; ref; ref = ref->next) {
 724                        struct object *o = deref_tag(the_repository,
 725                                                     lookup_object(the_repository,
 726                                                     ref->old_oid.hash),
 727                                                     NULL, 0);
 728
 729                        if (!o || o->type != OBJ_COMMIT || !(o->flags & COMPLETE))
 730                                continue;
 731
 732                        negotiator->known_common(negotiator,
 733                                                 (struct commit *)o);
 734                }
 735        }
 736
 737        save_commit_buffer = old_save_commit_buffer;
 738}
 739
 740/*
 741 * Returns 1 if every object pointed to by the given remote refs is available
 742 * locally and reachable from a local ref, and 0 otherwise.
 743 */
 744static int everything_local(struct fetch_pack_args *args,
 745                            struct ref **refs)
 746{
 747        struct ref *ref;
 748        int retval;
 749
 750        for (retval = 1, ref = *refs; ref ; ref = ref->next) {
 751                const struct object_id *remote = &ref->old_oid;
 752                struct object *o;
 753
 754                o = lookup_object(the_repository, remote->hash);
 755                if (!o || !(o->flags & COMPLETE)) {
 756                        retval = 0;
 757                        print_verbose(args, "want %s (%s)", oid_to_hex(remote),
 758                                      ref->name);
 759                        continue;
 760                }
 761                print_verbose(args, _("already have %s (%s)"), oid_to_hex(remote),
 762                              ref->name);
 763        }
 764
 765        return retval;
 766}
 767
 768static int sideband_demux(int in, int out, void *data)
 769{
 770        int *xd = data;
 771        int ret;
 772
 773        ret = recv_sideband("fetch-pack", xd[0], out);
 774        close(out);
 775        return ret;
 776}
 777
 778static int get_pack(struct fetch_pack_args *args,
 779                    int xd[2], char **pack_lockfile)
 780{
 781        struct async demux;
 782        int do_keep = args->keep_pack;
 783        const char *cmd_name;
 784        struct pack_header header;
 785        int pass_header = 0;
 786        struct child_process cmd = CHILD_PROCESS_INIT;
 787        int ret;
 788
 789        memset(&demux, 0, sizeof(demux));
 790        if (use_sideband) {
 791                /* xd[] is talking with upload-pack; subprocess reads from
 792                 * xd[0], spits out band#2 to stderr, and feeds us band#1
 793                 * through demux->out.
 794                 */
 795                demux.proc = sideband_demux;
 796                demux.data = xd;
 797                demux.out = -1;
 798                demux.isolate_sigpipe = 1;
 799                if (start_async(&demux))
 800                        die(_("fetch-pack: unable to fork off sideband demultiplexer"));
 801        }
 802        else
 803                demux.out = xd[0];
 804
 805        if (!args->keep_pack && unpack_limit) {
 806
 807                if (read_pack_header(demux.out, &header))
 808                        die(_("protocol error: bad pack header"));
 809                pass_header = 1;
 810                if (ntohl(header.hdr_entries) < unpack_limit)
 811                        do_keep = 0;
 812                else
 813                        do_keep = 1;
 814        }
 815
 816        if (alternate_shallow_file) {
 817                argv_array_push(&cmd.args, "--shallow-file");
 818                argv_array_push(&cmd.args, alternate_shallow_file);
 819        }
 820
 821        if (do_keep || args->from_promisor) {
 822                if (pack_lockfile)
 823                        cmd.out = -1;
 824                cmd_name = "index-pack";
 825                argv_array_push(&cmd.args, cmd_name);
 826                argv_array_push(&cmd.args, "--stdin");
 827                if (!args->quiet && !args->no_progress)
 828                        argv_array_push(&cmd.args, "-v");
 829                if (args->use_thin_pack)
 830                        argv_array_push(&cmd.args, "--fix-thin");
 831                if (do_keep && (args->lock_pack || unpack_limit)) {
 832                        char hostname[HOST_NAME_MAX + 1];
 833                        if (xgethostname(hostname, sizeof(hostname)))
 834                                xsnprintf(hostname, sizeof(hostname), "localhost");
 835                        argv_array_pushf(&cmd.args,
 836                                        "--keep=fetch-pack %"PRIuMAX " on %s",
 837                                        (uintmax_t)getpid(), hostname);
 838                }
 839                if (args->check_self_contained_and_connected)
 840                        argv_array_push(&cmd.args, "--check-self-contained-and-connected");
 841                if (args->from_promisor)
 842                        argv_array_push(&cmd.args, "--promisor");
 843        }
 844        else {
 845                cmd_name = "unpack-objects";
 846                argv_array_push(&cmd.args, cmd_name);
 847                if (args->quiet || args->no_progress)
 848                        argv_array_push(&cmd.args, "-q");
 849                args->check_self_contained_and_connected = 0;
 850        }
 851
 852        if (pass_header)
 853                argv_array_pushf(&cmd.args, "--pack_header=%"PRIu32",%"PRIu32,
 854                                 ntohl(header.hdr_version),
 855                                 ntohl(header.hdr_entries));
 856        if (fetch_fsck_objects >= 0
 857            ? fetch_fsck_objects
 858            : transfer_fsck_objects >= 0
 859            ? transfer_fsck_objects
 860            : 0) {
 861                if (args->from_promisor)
 862                        /*
 863                         * We cannot use --strict in index-pack because it
 864                         * checks both broken objects and links, but we only
 865                         * want to check for broken objects.
 866                         */
 867                        argv_array_push(&cmd.args, "--fsck-objects");
 868                else
 869                        argv_array_pushf(&cmd.args, "--strict%s",
 870                                         fsck_msg_types.buf);
 871        }
 872
 873        cmd.in = demux.out;
 874        cmd.git_cmd = 1;
 875        if (start_command(&cmd))
 876                die(_("fetch-pack: unable to fork off %s"), cmd_name);
 877        if (do_keep && pack_lockfile) {
 878                *pack_lockfile = index_pack_lockfile(cmd.out);
 879                close(cmd.out);
 880        }
 881
 882        if (!use_sideband)
 883                /* Closed by start_command() */
 884                xd[0] = -1;
 885
 886        ret = finish_command(&cmd);
 887        if (!ret || (args->check_self_contained_and_connected && ret == 1))
 888                args->self_contained_and_connected =
 889                        args->check_self_contained_and_connected &&
 890                        ret == 0;
 891        else
 892                die(_("%s failed"), cmd_name);
 893        if (use_sideband && finish_async(&demux))
 894                die(_("error in sideband demultiplexer"));
 895        return 0;
 896}
 897
 898static int cmp_ref_by_name(const void *a_, const void *b_)
 899{
 900        const struct ref *a = *((const struct ref **)a_);
 901        const struct ref *b = *((const struct ref **)b_);
 902        return strcmp(a->name, b->name);
 903}
 904
 905static struct ref *do_fetch_pack(struct fetch_pack_args *args,
 906                                 int fd[2],
 907                                 const struct ref *orig_ref,
 908                                 struct ref **sought, int nr_sought,
 909                                 struct shallow_info *si,
 910                                 char **pack_lockfile)
 911{
 912        struct ref *ref = copy_ref_list(orig_ref);
 913        struct object_id oid;
 914        const char *agent_feature;
 915        int agent_len;
 916        struct fetch_negotiator negotiator;
 917        fetch_negotiator_init(&negotiator, negotiation_algorithm);
 918
 919        sort_ref_list(&ref, ref_compare_name);
 920        QSORT(sought, nr_sought, cmp_ref_by_name);
 921
 922        if ((args->depth > 0 || is_repository_shallow(the_repository)) && !server_supports("shallow"))
 923                die(_("Server does not support shallow clients"));
 924        if (args->depth > 0 || args->deepen_since || args->deepen_not)
 925                args->deepen = 1;
 926        if (server_supports("multi_ack_detailed")) {
 927                print_verbose(args, _("Server supports multi_ack_detailed"));
 928                multi_ack = 2;
 929                if (server_supports("no-done")) {
 930                        print_verbose(args, _("Server supports no-done"));
 931                        if (args->stateless_rpc)
 932                                no_done = 1;
 933                }
 934        }
 935        else if (server_supports("multi_ack")) {
 936                print_verbose(args, _("Server supports multi_ack"));
 937                multi_ack = 1;
 938        }
 939        if (server_supports("side-band-64k")) {
 940                print_verbose(args, _("Server supports side-band-64k"));
 941                use_sideband = 2;
 942        }
 943        else if (server_supports("side-band")) {
 944                print_verbose(args, _("Server supports side-band"));
 945                use_sideband = 1;
 946        }
 947        if (server_supports("allow-tip-sha1-in-want")) {
 948                print_verbose(args, _("Server supports allow-tip-sha1-in-want"));
 949                allow_unadvertised_object_request |= ALLOW_TIP_SHA1;
 950        }
 951        if (server_supports("allow-reachable-sha1-in-want")) {
 952                print_verbose(args, _("Server supports allow-reachable-sha1-in-want"));
 953                allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
 954        }
 955        if (!server_supports("thin-pack"))
 956                args->use_thin_pack = 0;
 957        if (!server_supports("no-progress"))
 958                args->no_progress = 0;
 959        if (!server_supports("include-tag"))
 960                args->include_tag = 0;
 961        if (server_supports("ofs-delta"))
 962                print_verbose(args, _("Server supports ofs-delta"));
 963        else
 964                prefer_ofs_delta = 0;
 965
 966        if (server_supports("filter")) {
 967                server_supports_filtering = 1;
 968                print_verbose(args, _("Server supports filter"));
 969        } else if (args->filter_options.choice) {
 970                warning("filtering not recognized by server, ignoring");
 971        }
 972
 973        if ((agent_feature = server_feature_value("agent", &agent_len))) {
 974                agent_supported = 1;
 975                if (agent_len)
 976                        print_verbose(args, _("Server version is %.*s"),
 977                                      agent_len, agent_feature);
 978        }
 979        if (server_supports("deepen-since"))
 980                deepen_since_ok = 1;
 981        else if (args->deepen_since)
 982                die(_("Server does not support --shallow-since"));
 983        if (server_supports("deepen-not"))
 984                deepen_not_ok = 1;
 985        else if (args->deepen_not)
 986                die(_("Server does not support --shallow-exclude"));
 987        if (!server_supports("deepen-relative") && args->deepen_relative)
 988                die(_("Server does not support --deepen"));
 989
 990        mark_complete_and_common_ref(&negotiator, args, &ref);
 991        filter_refs(args, &ref, sought, nr_sought);
 992        if (everything_local(args, &ref)) {
 993                packet_flush(fd[1]);
 994                goto all_done;
 995        }
 996        if (find_common(&negotiator, args, fd, &oid, ref) < 0)
 997                if (!args->keep_pack)
 998                        /* When cloning, it is not unusual to have
 999                         * no common commit.
1000                         */
1001                        warning(_("no common commits"));
1002
1003        if (args->stateless_rpc)
1004                packet_flush(fd[1]);
1005        if (args->deepen)
1006                setup_alternate_shallow(&shallow_lock, &alternate_shallow_file,
1007                                        NULL);
1008        else if (si->nr_ours || si->nr_theirs)
1009                alternate_shallow_file = setup_temporary_shallow(si->shallow);
1010        else
1011                alternate_shallow_file = NULL;
1012        if (get_pack(args, fd, pack_lockfile))
1013                die(_("git fetch-pack: fetch failed."));
1014
1015 all_done:
1016        negotiator.release(&negotiator);
1017        return ref;
1018}
1019
1020static void add_shallow_requests(struct strbuf *req_buf,
1021                                 const struct fetch_pack_args *args)
1022{
1023        if (is_repository_shallow(the_repository))
1024                write_shallow_commits(req_buf, 1, NULL);
1025        if (args->depth > 0)
1026                packet_buf_write(req_buf, "deepen %d", args->depth);
1027        if (args->deepen_since) {
1028                timestamp_t max_age = approxidate(args->deepen_since);
1029                packet_buf_write(req_buf, "deepen-since %"PRItime, max_age);
1030        }
1031        if (args->deepen_not) {
1032                int i;
1033                for (i = 0; i < args->deepen_not->nr; i++) {
1034                        struct string_list_item *s = args->deepen_not->items + i;
1035                        packet_buf_write(req_buf, "deepen-not %s", s->string);
1036                }
1037        }
1038}
1039
1040static void add_wants(const struct ref *wants, struct strbuf *req_buf)
1041{
1042        int use_ref_in_want = server_supports_feature("fetch", "ref-in-want", 0);
1043
1044        for ( ; wants ; wants = wants->next) {
1045                const struct object_id *remote = &wants->old_oid;
1046                struct object *o;
1047
1048                /*
1049                 * If that object is complete (i.e. it is an ancestor of a
1050                 * local ref), we tell them we have it but do not have to
1051                 * tell them about its ancestors, which they already know
1052                 * about.
1053                 *
1054                 * We use lookup_object here because we are only
1055                 * interested in the case we *know* the object is
1056                 * reachable and we have already scanned it.
1057                 */
1058                if (((o = lookup_object(the_repository, remote->hash)) != NULL) &&
1059                    (o->flags & COMPLETE)) {
1060                        continue;
1061                }
1062
1063                if (!use_ref_in_want || wants->exact_oid)
1064                        packet_buf_write(req_buf, "want %s\n", oid_to_hex(remote));
1065                else
1066                        packet_buf_write(req_buf, "want-ref %s\n", wants->name);
1067        }
1068}
1069
1070static void add_common(struct strbuf *req_buf, struct oidset *common)
1071{
1072        struct oidset_iter iter;
1073        const struct object_id *oid;
1074        oidset_iter_init(common, &iter);
1075
1076        while ((oid = oidset_iter_next(&iter))) {
1077                packet_buf_write(req_buf, "have %s\n", oid_to_hex(oid));
1078        }
1079}
1080
1081static int add_haves(struct fetch_negotiator *negotiator,
1082                     struct strbuf *req_buf,
1083                     int *haves_to_send, int *in_vain)
1084{
1085        int ret = 0;
1086        int haves_added = 0;
1087        const struct object_id *oid;
1088
1089        while ((oid = negotiator->next(negotiator))) {
1090                packet_buf_write(req_buf, "have %s\n", oid_to_hex(oid));
1091                if (++haves_added >= *haves_to_send)
1092                        break;
1093        }
1094
1095        *in_vain += haves_added;
1096        if (!haves_added || *in_vain >= MAX_IN_VAIN) {
1097                /* Send Done */
1098                packet_buf_write(req_buf, "done\n");
1099                ret = 1;
1100        }
1101
1102        /* Increase haves to send on next round */
1103        *haves_to_send = next_flush(1, *haves_to_send);
1104
1105        return ret;
1106}
1107
1108static int send_fetch_request(struct fetch_negotiator *negotiator, int fd_out,
1109                              const struct fetch_pack_args *args,
1110                              const struct ref *wants, struct oidset *common,
1111                              int *haves_to_send, int *in_vain)
1112{
1113        int ret = 0;
1114        struct strbuf req_buf = STRBUF_INIT;
1115
1116        if (server_supports_v2("fetch", 1))
1117                packet_buf_write(&req_buf, "command=fetch");
1118        if (server_supports_v2("agent", 0))
1119                packet_buf_write(&req_buf, "agent=%s", git_user_agent_sanitized());
1120        if (args->server_options && args->server_options->nr &&
1121            server_supports_v2("server-option", 1)) {
1122                int i;
1123                for (i = 0; i < args->server_options->nr; i++)
1124                        packet_write_fmt(fd_out, "server-option=%s",
1125                                         args->server_options->items[i].string);
1126        }
1127
1128        packet_buf_delim(&req_buf);
1129        if (args->use_thin_pack)
1130                packet_buf_write(&req_buf, "thin-pack");
1131        if (args->no_progress)
1132                packet_buf_write(&req_buf, "no-progress");
1133        if (args->include_tag)
1134                packet_buf_write(&req_buf, "include-tag");
1135        if (prefer_ofs_delta)
1136                packet_buf_write(&req_buf, "ofs-delta");
1137
1138        /* Add shallow-info and deepen request */
1139        if (server_supports_feature("fetch", "shallow", 0))
1140                add_shallow_requests(&req_buf, args);
1141        else if (is_repository_shallow(the_repository) || args->deepen)
1142                die(_("Server does not support shallow requests"));
1143
1144        /* Add filter */
1145        if (server_supports_feature("fetch", "filter", 0) &&
1146            args->filter_options.choice) {
1147                print_verbose(args, _("Server supports filter"));
1148                packet_buf_write(&req_buf, "filter %s",
1149                                 args->filter_options.filter_spec);
1150        } else if (args->filter_options.choice) {
1151                warning("filtering not recognized by server, ignoring");
1152        }
1153
1154        /* add wants */
1155        add_wants(wants, &req_buf);
1156
1157        if (args->no_dependents) {
1158                packet_buf_write(&req_buf, "done");
1159                ret = 1;
1160        } else {
1161                /* Add all of the common commits we've found in previous rounds */
1162                add_common(&req_buf, common);
1163
1164                /* Add initial haves */
1165                ret = add_haves(negotiator, &req_buf, haves_to_send, in_vain);
1166        }
1167
1168        /* Send request */
1169        packet_buf_flush(&req_buf);
1170        write_or_die(fd_out, req_buf.buf, req_buf.len);
1171
1172        strbuf_release(&req_buf);
1173        return ret;
1174}
1175
1176/*
1177 * Processes a section header in a server's response and checks if it matches
1178 * `section`.  If the value of `peek` is 1, the header line will be peeked (and
1179 * not consumed); if 0, the line will be consumed and the function will die if
1180 * the section header doesn't match what was expected.
1181 */
1182static int process_section_header(struct packet_reader *reader,
1183                                  const char *section, int peek)
1184{
1185        int ret;
1186
1187        if (packet_reader_peek(reader) != PACKET_READ_NORMAL)
1188                die(_("error reading section header '%s'"), section);
1189
1190        ret = !strcmp(reader->line, section);
1191
1192        if (!peek) {
1193                if (!ret)
1194                        die(_("expected '%s', received '%s'"),
1195                            section, reader->line);
1196                packet_reader_read(reader);
1197        }
1198
1199        return ret;
1200}
1201
1202static int process_acks(struct fetch_negotiator *negotiator,
1203                        struct packet_reader *reader,
1204                        struct oidset *common)
1205{
1206        /* received */
1207        int received_ready = 0;
1208        int received_ack = 0;
1209
1210        process_section_header(reader, "acknowledgments", 0);
1211        while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
1212                const char *arg;
1213
1214                if (!strcmp(reader->line, "NAK"))
1215                        continue;
1216
1217                if (skip_prefix(reader->line, "ACK ", &arg)) {
1218                        struct object_id oid;
1219                        if (!get_oid_hex(arg, &oid)) {
1220                                struct commit *commit;
1221                                oidset_insert(common, &oid);
1222                                commit = lookup_commit(the_repository, &oid);
1223                                negotiator->ack(negotiator, commit);
1224                        }
1225                        continue;
1226                }
1227
1228                if (!strcmp(reader->line, "ready")) {
1229                        received_ready = 1;
1230                        continue;
1231                }
1232
1233                die(_("unexpected acknowledgment line: '%s'"), reader->line);
1234        }
1235
1236        if (reader->status != PACKET_READ_FLUSH &&
1237            reader->status != PACKET_READ_DELIM)
1238                die(_("error processing acks: %d"), reader->status);
1239
1240        /* return 0 if no common, 1 if there are common, or 2 if ready */
1241        return received_ready ? 2 : (received_ack ? 1 : 0);
1242}
1243
1244static void receive_shallow_info(struct fetch_pack_args *args,
1245                                 struct packet_reader *reader)
1246{
1247        process_section_header(reader, "shallow-info", 0);
1248        while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
1249                const char *arg;
1250                struct object_id oid;
1251
1252                if (skip_prefix(reader->line, "shallow ", &arg)) {
1253                        if (get_oid_hex(arg, &oid))
1254                                die(_("invalid shallow line: %s"), reader->line);
1255                        register_shallow(the_repository, &oid);
1256                        continue;
1257                }
1258                if (skip_prefix(reader->line, "unshallow ", &arg)) {
1259                        if (get_oid_hex(arg, &oid))
1260                                die(_("invalid unshallow line: %s"), reader->line);
1261                        if (!lookup_object(the_repository, oid.hash))
1262                                die(_("object not found: %s"), reader->line);
1263                        /* make sure that it is parsed as shallow */
1264                        if (!parse_object(the_repository, &oid))
1265                                die(_("error in object: %s"), reader->line);
1266                        if (unregister_shallow(&oid))
1267                                die(_("no shallow found: %s"), reader->line);
1268                        continue;
1269                }
1270                die(_("expected shallow/unshallow, got %s"), reader->line);
1271        }
1272
1273        if (reader->status != PACKET_READ_FLUSH &&
1274            reader->status != PACKET_READ_DELIM)
1275                die(_("error processing shallow info: %d"), reader->status);
1276
1277        setup_alternate_shallow(&shallow_lock, &alternate_shallow_file, NULL);
1278        args->deepen = 1;
1279}
1280
1281static void receive_wanted_refs(struct packet_reader *reader,
1282                                struct ref **sought, int nr_sought)
1283{
1284        process_section_header(reader, "wanted-refs", 0);
1285        while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
1286                struct object_id oid;
1287                const char *end;
1288                int i;
1289
1290                if (parse_oid_hex(reader->line, &oid, &end) || *end++ != ' ')
1291                        die(_("expected wanted-ref, got '%s'"), reader->line);
1292
1293                for (i = 0; i < nr_sought; i++) {
1294                        if (!strcmp(end, sought[i]->name)) {
1295                                oidcpy(&sought[i]->old_oid, &oid);
1296                                break;
1297                        }
1298                }
1299
1300                if (i == nr_sought)
1301                        die(_("unexpected wanted-ref: '%s'"), reader->line);
1302        }
1303
1304        if (reader->status != PACKET_READ_DELIM)
1305                die(_("error processing wanted refs: %d"), reader->status);
1306}
1307
1308enum fetch_state {
1309        FETCH_CHECK_LOCAL = 0,
1310        FETCH_SEND_REQUEST,
1311        FETCH_PROCESS_ACKS,
1312        FETCH_GET_PACK,
1313        FETCH_DONE,
1314};
1315
1316static struct ref *do_fetch_pack_v2(struct fetch_pack_args *args,
1317                                    int fd[2],
1318                                    const struct ref *orig_ref,
1319                                    struct ref **sought, int nr_sought,
1320                                    char **pack_lockfile)
1321{
1322        struct ref *ref = copy_ref_list(orig_ref);
1323        enum fetch_state state = FETCH_CHECK_LOCAL;
1324        struct oidset common = OIDSET_INIT;
1325        struct packet_reader reader;
1326        int in_vain = 0;
1327        int haves_to_send = INITIAL_FLUSH;
1328        struct fetch_negotiator negotiator;
1329        fetch_negotiator_init(&negotiator, negotiation_algorithm);
1330        packet_reader_init(&reader, fd[0], NULL, 0,
1331                           PACKET_READ_CHOMP_NEWLINE);
1332
1333        while (state != FETCH_DONE) {
1334                switch (state) {
1335                case FETCH_CHECK_LOCAL:
1336                        sort_ref_list(&ref, ref_compare_name);
1337                        QSORT(sought, nr_sought, cmp_ref_by_name);
1338
1339                        /* v2 supports these by default */
1340                        allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
1341                        use_sideband = 2;
1342                        if (args->depth > 0 || args->deepen_since || args->deepen_not)
1343                                args->deepen = 1;
1344
1345                        /* Filter 'ref' by 'sought' and those that aren't local */
1346                        mark_complete_and_common_ref(&negotiator, args, &ref);
1347                        filter_refs(args, &ref, sought, nr_sought);
1348                        if (everything_local(args, &ref))
1349                                state = FETCH_DONE;
1350                        else
1351                                state = FETCH_SEND_REQUEST;
1352
1353                        mark_tips(&negotiator, args->negotiation_tips);
1354                        for_each_cached_alternate(&negotiator,
1355                                                  insert_one_alternate_object);
1356                        break;
1357                case FETCH_SEND_REQUEST:
1358                        if (send_fetch_request(&negotiator, fd[1], args, ref,
1359                                               &common,
1360                                               &haves_to_send, &in_vain))
1361                                state = FETCH_GET_PACK;
1362                        else
1363                                state = FETCH_PROCESS_ACKS;
1364                        break;
1365                case FETCH_PROCESS_ACKS:
1366                        /* Process ACKs/NAKs */
1367                        switch (process_acks(&negotiator, &reader, &common)) {
1368                        case 2:
1369                                state = FETCH_GET_PACK;
1370                                break;
1371                        case 1:
1372                                in_vain = 0;
1373                                /* fallthrough */
1374                        default:
1375                                state = FETCH_SEND_REQUEST;
1376                                break;
1377                        }
1378                        break;
1379                case FETCH_GET_PACK:
1380                        /* Check for shallow-info section */
1381                        if (process_section_header(&reader, "shallow-info", 1))
1382                                receive_shallow_info(args, &reader);
1383
1384                        if (process_section_header(&reader, "wanted-refs", 1))
1385                                receive_wanted_refs(&reader, sought, nr_sought);
1386
1387                        /* get the pack */
1388                        process_section_header(&reader, "packfile", 0);
1389                        if (get_pack(args, fd, pack_lockfile))
1390                                die(_("git fetch-pack: fetch failed."));
1391
1392                        state = FETCH_DONE;
1393                        break;
1394                case FETCH_DONE:
1395                        continue;
1396                }
1397        }
1398
1399        negotiator.release(&negotiator);
1400        oidset_clear(&common);
1401        return ref;
1402}
1403
1404static int fetch_pack_config_cb(const char *var, const char *value, void *cb)
1405{
1406        if (strcmp(var, "fetch.fsck.skiplist") == 0) {
1407                const char *path;
1408
1409                if (git_config_pathname(&path, var, value))
1410                        return 1;
1411                strbuf_addf(&fsck_msg_types, "%cskiplist=%s",
1412                        fsck_msg_types.len ? ',' : '=', path);
1413                free((char *)path);
1414                return 0;
1415        }
1416
1417        if (skip_prefix(var, "fetch.fsck.", &var)) {
1418                if (is_valid_msg_type(var, value))
1419                        strbuf_addf(&fsck_msg_types, "%c%s=%s",
1420                                fsck_msg_types.len ? ',' : '=', var, value);
1421                else
1422                        warning("Skipping unknown msg id '%s'", var);
1423                return 0;
1424        }
1425
1426        return git_default_config(var, value, cb);
1427}
1428
1429static void fetch_pack_config(void)
1430{
1431        git_config_get_int("fetch.unpacklimit", &fetch_unpack_limit);
1432        git_config_get_int("transfer.unpacklimit", &transfer_unpack_limit);
1433        git_config_get_bool("repack.usedeltabaseoffset", &prefer_ofs_delta);
1434        git_config_get_bool("fetch.fsckobjects", &fetch_fsck_objects);
1435        git_config_get_bool("transfer.fsckobjects", &transfer_fsck_objects);
1436        git_config_get_string("fetch.negotiationalgorithm",
1437                              &negotiation_algorithm);
1438
1439        git_config(fetch_pack_config_cb, NULL);
1440}
1441
1442static void fetch_pack_setup(void)
1443{
1444        static int did_setup;
1445        if (did_setup)
1446                return;
1447        fetch_pack_config();
1448        if (0 <= transfer_unpack_limit)
1449                unpack_limit = transfer_unpack_limit;
1450        else if (0 <= fetch_unpack_limit)
1451                unpack_limit = fetch_unpack_limit;
1452        did_setup = 1;
1453}
1454
1455static int remove_duplicates_in_refs(struct ref **ref, int nr)
1456{
1457        struct string_list names = STRING_LIST_INIT_NODUP;
1458        int src, dst;
1459
1460        for (src = dst = 0; src < nr; src++) {
1461                struct string_list_item *item;
1462                item = string_list_insert(&names, ref[src]->name);
1463                if (item->util)
1464                        continue; /* already have it */
1465                item->util = ref[src];
1466                if (src != dst)
1467                        ref[dst] = ref[src];
1468                dst++;
1469        }
1470        for (src = dst; src < nr; src++)
1471                ref[src] = NULL;
1472        string_list_clear(&names, 0);
1473        return dst;
1474}
1475
1476static void update_shallow(struct fetch_pack_args *args,
1477                           struct ref **sought, int nr_sought,
1478                           struct shallow_info *si)
1479{
1480        struct oid_array ref = OID_ARRAY_INIT;
1481        int *status;
1482        int i;
1483
1484        if (args->deepen && alternate_shallow_file) {
1485                if (*alternate_shallow_file == '\0') { /* --unshallow */
1486                        unlink_or_warn(git_path_shallow(the_repository));
1487                        rollback_lock_file(&shallow_lock);
1488                } else
1489                        commit_lock_file(&shallow_lock);
1490                return;
1491        }
1492
1493        if (!si->shallow || !si->shallow->nr)
1494                return;
1495
1496        if (args->cloning) {
1497                /*
1498                 * remote is shallow, but this is a clone, there are
1499                 * no objects in repo to worry about. Accept any
1500                 * shallow points that exist in the pack (iow in repo
1501                 * after get_pack() and reprepare_packed_git())
1502                 */
1503                struct oid_array extra = OID_ARRAY_INIT;
1504                struct object_id *oid = si->shallow->oid;
1505                for (i = 0; i < si->shallow->nr; i++)
1506                        if (has_object_file(&oid[i]))
1507                                oid_array_append(&extra, &oid[i]);
1508                if (extra.nr) {
1509                        setup_alternate_shallow(&shallow_lock,
1510                                                &alternate_shallow_file,
1511                                                &extra);
1512                        commit_lock_file(&shallow_lock);
1513                }
1514                oid_array_clear(&extra);
1515                return;
1516        }
1517
1518        if (!si->nr_ours && !si->nr_theirs)
1519                return;
1520
1521        remove_nonexistent_theirs_shallow(si);
1522        if (!si->nr_ours && !si->nr_theirs)
1523                return;
1524        for (i = 0; i < nr_sought; i++)
1525                oid_array_append(&ref, &sought[i]->old_oid);
1526        si->ref = &ref;
1527
1528        if (args->update_shallow) {
1529                /*
1530                 * remote is also shallow, .git/shallow may be updated
1531                 * so all refs can be accepted. Make sure we only add
1532                 * shallow roots that are actually reachable from new
1533                 * refs.
1534                 */
1535                struct oid_array extra = OID_ARRAY_INIT;
1536                struct object_id *oid = si->shallow->oid;
1537                assign_shallow_commits_to_refs(si, NULL, NULL);
1538                if (!si->nr_ours && !si->nr_theirs) {
1539                        oid_array_clear(&ref);
1540                        return;
1541                }
1542                for (i = 0; i < si->nr_ours; i++)
1543                        oid_array_append(&extra, &oid[si->ours[i]]);
1544                for (i = 0; i < si->nr_theirs; i++)
1545                        oid_array_append(&extra, &oid[si->theirs[i]]);
1546                setup_alternate_shallow(&shallow_lock,
1547                                        &alternate_shallow_file,
1548                                        &extra);
1549                commit_lock_file(&shallow_lock);
1550                oid_array_clear(&extra);
1551                oid_array_clear(&ref);
1552                return;
1553        }
1554
1555        /*
1556         * remote is also shallow, check what ref is safe to update
1557         * without updating .git/shallow
1558         */
1559        status = xcalloc(nr_sought, sizeof(*status));
1560        assign_shallow_commits_to_refs(si, NULL, status);
1561        if (si->nr_ours || si->nr_theirs) {
1562                for (i = 0; i < nr_sought; i++)
1563                        if (status[i])
1564                                sought[i]->status = REF_STATUS_REJECT_SHALLOW;
1565        }
1566        free(status);
1567        oid_array_clear(&ref);
1568}
1569
1570static int iterate_ref_map(void *cb_data, struct object_id *oid)
1571{
1572        struct ref **rm = cb_data;
1573        struct ref *ref = *rm;
1574
1575        if (!ref)
1576                return -1; /* end of the list */
1577        *rm = ref->next;
1578        oidcpy(oid, &ref->old_oid);
1579        return 0;
1580}
1581
1582struct ref *fetch_pack(struct fetch_pack_args *args,
1583                       int fd[], struct child_process *conn,
1584                       const struct ref *ref,
1585                       const char *dest,
1586                       struct ref **sought, int nr_sought,
1587                       struct oid_array *shallow,
1588                       char **pack_lockfile,
1589                       enum protocol_version version)
1590{
1591        struct ref *ref_cpy;
1592        struct shallow_info si;
1593
1594        fetch_pack_setup();
1595        if (nr_sought)
1596                nr_sought = remove_duplicates_in_refs(sought, nr_sought);
1597
1598        if (!ref) {
1599                packet_flush(fd[1]);
1600                die(_("no matching remote head"));
1601        }
1602        prepare_shallow_info(&si, shallow);
1603        if (version == protocol_v2)
1604                ref_cpy = do_fetch_pack_v2(args, fd, ref, sought, nr_sought,
1605                                           pack_lockfile);
1606        else
1607                ref_cpy = do_fetch_pack(args, fd, ref, sought, nr_sought,
1608                                        &si, pack_lockfile);
1609        reprepare_packed_git(the_repository);
1610
1611        if (!args->cloning && args->deepen) {
1612                struct check_connected_options opt = CHECK_CONNECTED_INIT;
1613                struct ref *iterator = ref_cpy;
1614                opt.shallow_file = alternate_shallow_file;
1615                if (args->deepen)
1616                        opt.is_deepening_fetch = 1;
1617                if (check_connected(iterate_ref_map, &iterator, &opt)) {
1618                        error(_("remote did not send all necessary objects"));
1619                        free_refs(ref_cpy);
1620                        ref_cpy = NULL;
1621                        rollback_lock_file(&shallow_lock);
1622                        goto cleanup;
1623                }
1624                args->connectivity_checked = 1;
1625        }
1626
1627        update_shallow(args, sought, nr_sought, &si);
1628cleanup:
1629        clear_shallow_info(&si);
1630        return ref_cpy;
1631}
1632
1633int report_unmatched_refs(struct ref **sought, int nr_sought)
1634{
1635        int i, ret = 0;
1636
1637        for (i = 0; i < nr_sought; i++) {
1638                if (!sought[i])
1639                        continue;
1640                switch (sought[i]->match_status) {
1641                case REF_MATCHED:
1642                        continue;
1643                case REF_NOT_MATCHED:
1644                        error(_("no such remote ref %s"), sought[i]->name);
1645                        break;
1646                case REF_UNADVERTISED_NOT_ALLOWED:
1647                        error(_("Server does not allow request for unadvertised object %s"),
1648                              sought[i]->name);
1649                        break;
1650                }
1651                ret = 1;
1652        }
1653        return ret;
1654}