fetch-pack.con commit Merge branch 'bw/clone-ref-prefixes' (2d7a202)
   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
  25static int transfer_unpack_limit = -1;
  26static int fetch_unpack_limit = -1;
  27static int unpack_limit = 100;
  28static int prefer_ofs_delta = 1;
  29static int no_done;
  30static int deepen_since_ok;
  31static int deepen_not_ok;
  32static int fetch_fsck_objects = -1;
  33static int transfer_fsck_objects = -1;
  34static int agent_supported;
  35static int server_supports_filtering;
  36static struct lock_file shallow_lock;
  37static const char *alternate_shallow_file;
  38static char *negotiation_algorithm;
  39
  40/* Remember to update object flag allocation in object.h */
  41#define COMPLETE        (1U << 0)
  42#define ALTERNATE       (1U << 1)
  43
  44/*
  45 * After sending this many "have"s if we do not get any new ACK , we
  46 * give up traversing our history.
  47 */
  48#define MAX_IN_VAIN 256
  49
  50static int multi_ack, use_sideband;
  51/* Allow specifying sha1 if it is a ref tip. */
  52#define ALLOW_TIP_SHA1  01
  53/* Allow request of a sha1 if it is reachable from a ref (possibly hidden ref). */
  54#define ALLOW_REACHABLE_SHA1    02
  55static unsigned int allow_unadvertised_object_request;
  56
  57__attribute__((format (printf, 2, 3)))
  58static inline void print_verbose(const struct fetch_pack_args *args,
  59                                 const char *fmt, ...)
  60{
  61        va_list params;
  62
  63        if (!args->verbose)
  64                return;
  65
  66        va_start(params, fmt);
  67        vfprintf(stderr, fmt, params);
  68        va_end(params);
  69        fputc('\n', stderr);
  70}
  71
  72struct alternate_object_cache {
  73        struct object **items;
  74        size_t nr, alloc;
  75};
  76
  77static void cache_one_alternate(const char *refname,
  78                                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, int fd)
 138{
 139        if (args->stateless_rpc && args->deepen) {
 140                /* If we sent a depth we will get back "duplicate"
 141                 * shallow and unshallow commands every time there
 142                 * is a block of have lines exchanged.
 143                 */
 144                char *line;
 145                while ((line = packet_read_line(fd, NULL))) {
 146                        if (starts_with(line, "shallow "))
 147                                continue;
 148                        if (starts_with(line, "unshallow "))
 149                                continue;
 150                        die(_("git fetch-pack: expected shallow list"));
 151                }
 152        }
 153}
 154
 155static enum ack_type get_ack(int fd, struct object_id *result_oid)
 156{
 157        int len;
 158        char *line = packet_read_line(fd, &len);
 159        const char *arg;
 160
 161        if (!line)
 162                die(_("git fetch-pack: expected ACK/NAK, got a flush packet"));
 163        if (!strcmp(line, "NAK"))
 164                return NAK;
 165        if (skip_prefix(line, "ACK ", &arg)) {
 166                if (!get_oid_hex(arg, result_oid)) {
 167                        arg += 40;
 168                        len -= arg - line;
 169                        if (len < 1)
 170                                return ACK;
 171                        if (strstr(arg, "continue"))
 172                                return ACK_continue;
 173                        if (strstr(arg, "common"))
 174                                return ACK_common;
 175                        if (strstr(arg, "ready"))
 176                                return ACK_ready;
 177                        return ACK;
 178                }
 179        }
 180        if (skip_prefix(line, "ERR ", &arg))
 181                die(_("remote error: %s"), arg);
 182        die(_("git fetch-pack: expected ACK/NAK, got '%s'"), line);
 183}
 184
 185static void send_request(struct fetch_pack_args *args,
 186                         int fd, struct strbuf *buf)
 187{
 188        if (args->stateless_rpc) {
 189                send_sideband(fd, -1, buf->buf, buf->len, LARGE_PACKET_MAX);
 190                packet_flush(fd);
 191        } else
 192                write_or_die(fd, buf->buf, buf->len);
 193}
 194
 195static void insert_one_alternate_object(struct fetch_negotiator *negotiator,
 196                                        struct object *obj)
 197{
 198        rev_list_insert_ref(negotiator, NULL, &obj->oid);
 199}
 200
 201#define INITIAL_FLUSH 16
 202#define PIPESAFE_FLUSH 32
 203#define LARGE_FLUSH 16384
 204
 205static int next_flush(int stateless_rpc, int count)
 206{
 207        if (stateless_rpc) {
 208                if (count < LARGE_FLUSH)
 209                        count <<= 1;
 210                else
 211                        count = count * 11 / 10;
 212        } else {
 213                if (count < PIPESAFE_FLUSH)
 214                        count <<= 1;
 215                else
 216                        count += PIPESAFE_FLUSH;
 217        }
 218        return count;
 219}
 220
 221static void mark_tips(struct fetch_negotiator *negotiator,
 222                      const struct oid_array *negotiation_tips)
 223{
 224        int i;
 225
 226        if (!negotiation_tips) {
 227                for_each_ref(rev_list_insert_ref_oid, negotiator);
 228                return;
 229        }
 230
 231        for (i = 0; i < negotiation_tips->nr; i++)
 232                rev_list_insert_ref(negotiator, NULL,
 233                                    &negotiation_tips->oid[i]);
 234        return;
 235}
 236
 237static int find_common(struct fetch_negotiator *negotiator,
 238                       struct fetch_pack_args *args,
 239                       int fd[2], struct object_id *result_oid,
 240                       struct ref *refs)
 241{
 242        int fetching;
 243        int count = 0, flushes = 0, flush_at = INITIAL_FLUSH, retval;
 244        const struct object_id *oid;
 245        unsigned in_vain = 0;
 246        int got_continue = 0;
 247        int got_ready = 0;
 248        struct strbuf req_buf = STRBUF_INIT;
 249        size_t state_len = 0;
 250
 251        if (args->stateless_rpc && multi_ack == 1)
 252                die(_("--stateless-rpc requires multi_ack_detailed"));
 253
 254        mark_tips(negotiator, args->negotiation_tips);
 255        for_each_cached_alternate(negotiator, insert_one_alternate_object);
 256
 257        fetching = 0;
 258        for ( ; refs ; refs = refs->next) {
 259                struct object_id *remote = &refs->old_oid;
 260                const char *remote_hex;
 261                struct object *o;
 262
 263                /*
 264                 * If that object is complete (i.e. it is an ancestor of a
 265                 * local ref), we tell them we have it but do not have to
 266                 * tell them about its ancestors, which they already know
 267                 * about.
 268                 *
 269                 * We use lookup_object here because we are only
 270                 * interested in the case we *know* the object is
 271                 * reachable and we have already scanned it.
 272                 */
 273                if (((o = lookup_object(the_repository, remote->hash)) != NULL) &&
 274                                (o->flags & COMPLETE)) {
 275                        continue;
 276                }
 277
 278                remote_hex = oid_to_hex(remote);
 279                if (!fetching) {
 280                        struct strbuf c = STRBUF_INIT;
 281                        if (multi_ack == 2)     strbuf_addstr(&c, " multi_ack_detailed");
 282                        if (multi_ack == 1)     strbuf_addstr(&c, " multi_ack");
 283                        if (no_done)            strbuf_addstr(&c, " no-done");
 284                        if (use_sideband == 2)  strbuf_addstr(&c, " side-band-64k");
 285                        if (use_sideband == 1)  strbuf_addstr(&c, " side-band");
 286                        if (args->deepen_relative) strbuf_addstr(&c, " deepen-relative");
 287                        if (args->use_thin_pack) strbuf_addstr(&c, " thin-pack");
 288                        if (args->no_progress)   strbuf_addstr(&c, " no-progress");
 289                        if (args->include_tag)   strbuf_addstr(&c, " include-tag");
 290                        if (prefer_ofs_delta)   strbuf_addstr(&c, " ofs-delta");
 291                        if (deepen_since_ok)    strbuf_addstr(&c, " deepen-since");
 292                        if (deepen_not_ok)      strbuf_addstr(&c, " deepen-not");
 293                        if (agent_supported)    strbuf_addf(&c, " agent=%s",
 294                                                            git_user_agent_sanitized());
 295                        if (args->filter_options.choice)
 296                                strbuf_addstr(&c, " filter");
 297                        packet_buf_write(&req_buf, "want %s%s\n", remote_hex, c.buf);
 298                        strbuf_release(&c);
 299                } else
 300                        packet_buf_write(&req_buf, "want %s\n", remote_hex);
 301                fetching++;
 302        }
 303
 304        if (!fetching) {
 305                strbuf_release(&req_buf);
 306                packet_flush(fd[1]);
 307                return 1;
 308        }
 309
 310        if (is_repository_shallow(the_repository))
 311                write_shallow_commits(&req_buf, 1, NULL);
 312        if (args->depth > 0)
 313                packet_buf_write(&req_buf, "deepen %d", args->depth);
 314        if (args->deepen_since) {
 315                timestamp_t max_age = approxidate(args->deepen_since);
 316                packet_buf_write(&req_buf, "deepen-since %"PRItime, max_age);
 317        }
 318        if (args->deepen_not) {
 319                int i;
 320                for (i = 0; i < args->deepen_not->nr; i++) {
 321                        struct string_list_item *s = args->deepen_not->items + i;
 322                        packet_buf_write(&req_buf, "deepen-not %s", s->string);
 323                }
 324        }
 325        if (server_supports_filtering && args->filter_options.choice)
 326                packet_buf_write(&req_buf, "filter %s",
 327                                 args->filter_options.filter_spec);
 328        packet_buf_flush(&req_buf);
 329        state_len = req_buf.len;
 330
 331        if (args->deepen) {
 332                char *line;
 333                const char *arg;
 334                struct object_id oid;
 335
 336                send_request(args, fd[1], &req_buf);
 337                while ((line = packet_read_line(fd[0], NULL))) {
 338                        if (skip_prefix(line, "shallow ", &arg)) {
 339                                if (get_oid_hex(arg, &oid))
 340                                        die(_("invalid shallow line: %s"), line);
 341                                register_shallow(the_repository, &oid);
 342                                continue;
 343                        }
 344                        if (skip_prefix(line, "unshallow ", &arg)) {
 345                                if (get_oid_hex(arg, &oid))
 346                                        die(_("invalid unshallow line: %s"), line);
 347                                if (!lookup_object(the_repository, oid.hash))
 348                                        die(_("object not found: %s"), line);
 349                                /* make sure that it is parsed as shallow */
 350                                if (!parse_object(the_repository, &oid))
 351                                        die(_("error in object: %s"), line);
 352                                if (unregister_shallow(&oid))
 353                                        die(_("no shallow found: %s"), line);
 354                                continue;
 355                        }
 356                        die(_("expected shallow/unshallow, got %s"), line);
 357                }
 358        } else if (!args->stateless_rpc)
 359                send_request(args, fd[1], &req_buf);
 360
 361        if (!args->stateless_rpc) {
 362                /* If we aren't using the stateless-rpc interface
 363                 * we don't need to retain the headers.
 364                 */
 365                strbuf_setlen(&req_buf, 0);
 366                state_len = 0;
 367        }
 368
 369        flushes = 0;
 370        retval = -1;
 371        if (args->no_dependents)
 372                goto done;
 373        while ((oid = negotiator->next(negotiator))) {
 374                packet_buf_write(&req_buf, "have %s\n", oid_to_hex(oid));
 375                print_verbose(args, "have %s", oid_to_hex(oid));
 376                in_vain++;
 377                if (flush_at <= ++count) {
 378                        int ack;
 379
 380                        packet_buf_flush(&req_buf);
 381                        send_request(args, fd[1], &req_buf);
 382                        strbuf_setlen(&req_buf, state_len);
 383                        flushes++;
 384                        flush_at = next_flush(args->stateless_rpc, count);
 385
 386                        /*
 387                         * We keep one window "ahead" of the other side, and
 388                         * will wait for an ACK only on the next one
 389                         */
 390                        if (!args->stateless_rpc && count == INITIAL_FLUSH)
 391                                continue;
 392
 393                        consume_shallow_list(args, fd[0]);
 394                        do {
 395                                ack = get_ack(fd[0], result_oid);
 396                                if (ack)
 397                                        print_verbose(args, _("got %s %d %s"), "ack",
 398                                                      ack, oid_to_hex(result_oid));
 399                                switch (ack) {
 400                                case ACK:
 401                                        flushes = 0;
 402                                        multi_ack = 0;
 403                                        retval = 0;
 404                                        goto done;
 405                                case ACK_common:
 406                                case ACK_ready:
 407                                case ACK_continue: {
 408                                        struct commit *commit =
 409                                                lookup_commit(the_repository,
 410                                                              result_oid);
 411                                        int was_common;
 412
 413                                        if (!commit)
 414                                                die(_("invalid commit %s"), oid_to_hex(result_oid));
 415                                        was_common = negotiator->ack(negotiator, commit);
 416                                        if (args->stateless_rpc
 417                                         && ack == ACK_common
 418                                         && !was_common) {
 419                                                /* We need to replay the have for this object
 420                                                 * on the next RPC request so the peer knows
 421                                                 * it is in common with us.
 422                                                 */
 423                                                const char *hex = oid_to_hex(result_oid);
 424                                                packet_buf_write(&req_buf, "have %s\n", hex);
 425                                                state_len = req_buf.len;
 426                                                /*
 427                                                 * Reset in_vain because an ack
 428                                                 * for this commit has not been
 429                                                 * seen.
 430                                                 */
 431                                                in_vain = 0;
 432                                        } else if (!args->stateless_rpc
 433                                                   || ack != ACK_common)
 434                                                in_vain = 0;
 435                                        retval = 0;
 436                                        got_continue = 1;
 437                                        if (ack == ACK_ready)
 438                                                got_ready = 1;
 439                                        break;
 440                                        }
 441                                }
 442                        } while (ack);
 443                        flushes--;
 444                        if (got_continue && MAX_IN_VAIN < in_vain) {
 445                                print_verbose(args, _("giving up"));
 446                                break; /* give up */
 447                        }
 448                        if (got_ready)
 449                                break;
 450                }
 451        }
 452done:
 453        if (!got_ready || !no_done) {
 454                packet_buf_write(&req_buf, "done\n");
 455                send_request(args, fd[1], &req_buf);
 456        }
 457        print_verbose(args, _("done"));
 458        if (retval != 0) {
 459                multi_ack = 0;
 460                flushes++;
 461        }
 462        strbuf_release(&req_buf);
 463
 464        if (!got_ready || !no_done)
 465                consume_shallow_list(args, fd[0]);
 466        while (flushes || multi_ack) {
 467                int ack = get_ack(fd[0], result_oid);
 468                if (ack) {
 469                        print_verbose(args, _("got %s (%d) %s"), "ack",
 470                                      ack, oid_to_hex(result_oid));
 471                        if (ack == ACK)
 472                                return 0;
 473                        multi_ack = 1;
 474                        continue;
 475                }
 476                flushes--;
 477        }
 478        /* it is no error to fetch into a completely empty repo */
 479        return count ? retval : 0;
 480}
 481
 482static struct commit_list *complete;
 483
 484static int mark_complete(const struct object_id *oid)
 485{
 486        struct object *o = parse_object(the_repository, oid);
 487
 488        while (o && o->type == OBJ_TAG) {
 489                struct tag *t = (struct tag *) o;
 490                if (!t->tagged)
 491                        break; /* broken repository */
 492                o->flags |= COMPLETE;
 493                o = parse_object(the_repository, &t->tagged->oid);
 494        }
 495        if (o && o->type == OBJ_COMMIT) {
 496                struct commit *commit = (struct commit *)o;
 497                if (!(commit->object.flags & COMPLETE)) {
 498                        commit->object.flags |= COMPLETE;
 499                        commit_list_insert(commit, &complete);
 500                }
 501        }
 502        return 0;
 503}
 504
 505static int mark_complete_oid(const char *refname, const struct object_id *oid,
 506                             int flag, void *cb_data)
 507{
 508        return mark_complete(oid);
 509}
 510
 511static void mark_recent_complete_commits(struct fetch_pack_args *args,
 512                                         timestamp_t cutoff)
 513{
 514        while (complete && cutoff <= complete->item->date) {
 515                print_verbose(args, _("Marking %s as complete"),
 516                              oid_to_hex(&complete->item->object.oid));
 517                pop_most_recent_commit(&complete, COMPLETE);
 518        }
 519}
 520
 521static void add_refs_to_oidset(struct oidset *oids, struct ref *refs)
 522{
 523        for (; refs; refs = refs->next)
 524                oidset_insert(oids, &refs->old_oid);
 525}
 526
 527static int tip_oids_contain(struct oidset *tip_oids,
 528                            struct ref *unmatched, struct ref *newlist,
 529                            const struct object_id *id)
 530{
 531        /*
 532         * Note that this only looks at the ref lists the first time it's
 533         * called. This works out in filter_refs() because even though it may
 534         * add to "newlist" between calls, the additions will always be for
 535         * oids that are already in the set.
 536         */
 537        if (!tip_oids->map.map.tablesize) {
 538                add_refs_to_oidset(tip_oids, unmatched);
 539                add_refs_to_oidset(tip_oids, newlist);
 540        }
 541        return oidset_contains(tip_oids, id);
 542}
 543
 544static void filter_refs(struct fetch_pack_args *args,
 545                        struct ref **refs,
 546                        struct ref **sought, int nr_sought)
 547{
 548        struct ref *newlist = NULL;
 549        struct ref **newtail = &newlist;
 550        struct ref *unmatched = NULL;
 551        struct ref *ref, *next;
 552        struct oidset tip_oids = OIDSET_INIT;
 553        int i;
 554
 555        i = 0;
 556        for (ref = *refs; ref; ref = next) {
 557                int keep = 0;
 558                next = ref->next;
 559
 560                if (starts_with(ref->name, "refs/") &&
 561                    check_refname_format(ref->name, 0))
 562                        ; /* trash */
 563                else {
 564                        while (i < nr_sought) {
 565                                int cmp = strcmp(ref->name, sought[i]->name);
 566                                if (cmp < 0)
 567                                        break; /* definitely do not have it */
 568                                else if (cmp == 0) {
 569                                        keep = 1; /* definitely have it */
 570                                        sought[i]->match_status = REF_MATCHED;
 571                                }
 572                                i++;
 573                        }
 574
 575                        if (!keep && args->fetch_all &&
 576                            (!args->deepen || !starts_with(ref->name, "refs/tags/")))
 577                                keep = 1;
 578                }
 579
 580                if (keep) {
 581                        *newtail = ref;
 582                        ref->next = NULL;
 583                        newtail = &ref->next;
 584                } else {
 585                        ref->next = unmatched;
 586                        unmatched = ref;
 587                }
 588        }
 589
 590        /* Append unmatched requests to the list */
 591        for (i = 0; i < nr_sought; i++) {
 592                struct object_id oid;
 593                const char *p;
 594
 595                ref = sought[i];
 596                if (ref->match_status != REF_NOT_MATCHED)
 597                        continue;
 598                if (parse_oid_hex(ref->name, &oid, &p) ||
 599                    *p != '\0' ||
 600                    oidcmp(&oid, &ref->old_oid))
 601                        continue;
 602
 603                if ((allow_unadvertised_object_request &
 604                     (ALLOW_TIP_SHA1 | ALLOW_REACHABLE_SHA1)) ||
 605                    tip_oids_contain(&tip_oids, unmatched, newlist,
 606                                     &ref->old_oid)) {
 607                        ref->match_status = REF_MATCHED;
 608                        *newtail = copy_ref(ref);
 609                        newtail = &(*newtail)->next;
 610                } else {
 611                        ref->match_status = REF_UNADVERTISED_NOT_ALLOWED;
 612                }
 613        }
 614
 615        oidset_clear(&tip_oids);
 616        for (ref = unmatched; ref; ref = next) {
 617                next = ref->next;
 618                free(ref);
 619        }
 620
 621        *refs = newlist;
 622}
 623
 624static void mark_alternate_complete(struct fetch_negotiator *unused,
 625                                    struct object *obj)
 626{
 627        mark_complete(&obj->oid);
 628}
 629
 630struct loose_object_iter {
 631        struct oidset *loose_object_set;
 632        struct ref *refs;
 633};
 634
 635/*
 636 *  If the number of refs is not larger than the number of loose objects,
 637 *  this function stops inserting.
 638 */
 639static int add_loose_objects_to_set(const struct object_id *oid,
 640                                    const char *path,
 641                                    void *data)
 642{
 643        struct loose_object_iter *iter = data;
 644        oidset_insert(iter->loose_object_set, oid);
 645        if (iter->refs == NULL)
 646                return 1;
 647
 648        iter->refs = iter->refs->next;
 649        return 0;
 650}
 651
 652/*
 653 * Mark recent commits available locally and reachable from a local ref as
 654 * COMPLETE. If args->no_dependents is false, also mark COMPLETE remote refs as
 655 * COMMON_REF (otherwise, we are not planning to participate in negotiation, and
 656 * thus do not need COMMON_REF marks).
 657 *
 658 * The cutoff time for recency is determined by this heuristic: it is the
 659 * earliest commit time of the objects in refs that are commits and that we know
 660 * the commit time of.
 661 */
 662static void mark_complete_and_common_ref(struct fetch_negotiator *negotiator,
 663                                         struct fetch_pack_args *args,
 664                                         struct ref **refs)
 665{
 666        struct ref *ref;
 667        int old_save_commit_buffer = save_commit_buffer;
 668        timestamp_t cutoff = 0;
 669        struct oidset loose_oid_set = OIDSET_INIT;
 670        int use_oidset = 0;
 671        struct loose_object_iter iter = {&loose_oid_set, *refs};
 672
 673        /* Enumerate all loose objects or know refs are not so many. */
 674        use_oidset = !for_each_loose_object(add_loose_objects_to_set,
 675                                            &iter, 0);
 676
 677        save_commit_buffer = 0;
 678
 679        for (ref = *refs; ref; ref = ref->next) {
 680                struct object *o;
 681                unsigned int flags = OBJECT_INFO_QUICK;
 682
 683                if (use_oidset &&
 684                    !oidset_contains(&loose_oid_set, &ref->old_oid)) {
 685                        /*
 686                         * I know this does not exist in the loose form,
 687                         * so check if it exists in a non-loose form.
 688                         */
 689                        flags |= OBJECT_INFO_IGNORE_LOOSE;
 690                }
 691
 692                if (!has_object_file_with_flags(&ref->old_oid, flags))
 693                        continue;
 694                o = parse_object(the_repository, &ref->old_oid);
 695                if (!o)
 696                        continue;
 697
 698                /* We already have it -- which may mean that we were
 699                 * in sync with the other side at some time after
 700                 * that (it is OK if we guess wrong here).
 701                 */
 702                if (o->type == OBJ_COMMIT) {
 703                        struct commit *commit = (struct commit *)o;
 704                        if (!cutoff || cutoff < commit->date)
 705                                cutoff = commit->date;
 706                }
 707        }
 708
 709        oidset_clear(&loose_oid_set);
 710
 711        if (!args->no_dependents) {
 712                if (!args->deepen) {
 713                        for_each_ref(mark_complete_oid, NULL);
 714                        for_each_cached_alternate(NULL, mark_alternate_complete);
 715                        commit_list_sort_by_date(&complete);
 716                        if (cutoff)
 717                                mark_recent_complete_commits(args, cutoff);
 718                }
 719
 720                /*
 721                 * Mark all complete remote refs as common refs.
 722                 * Don't mark them common yet; the server has to be told so first.
 723                 */
 724                for (ref = *refs; ref; ref = ref->next) {
 725                        struct object *o = deref_tag(the_repository,
 726                                                     lookup_object(the_repository,
 727                                                     ref->old_oid.hash),
 728                                                     NULL, 0);
 729
 730                        if (!o || o->type != OBJ_COMMIT || !(o->flags & COMPLETE))
 731                                continue;
 732
 733                        negotiator->known_common(negotiator,
 734                                                 (struct commit *)o);
 735                }
 736        }
 737
 738        save_commit_buffer = old_save_commit_buffer;
 739}
 740
 741/*
 742 * Returns 1 if every object pointed to by the given remote refs is available
 743 * locally and reachable from a local ref, and 0 otherwise.
 744 */
 745static int everything_local(struct fetch_pack_args *args,
 746                            struct ref **refs)
 747{
 748        struct ref *ref;
 749        int retval;
 750
 751        for (retval = 1, ref = *refs; ref ; ref = ref->next) {
 752                const struct object_id *remote = &ref->old_oid;
 753                struct object *o;
 754
 755                o = lookup_object(the_repository, remote->hash);
 756                if (!o || !(o->flags & COMPLETE)) {
 757                        retval = 0;
 758                        print_verbose(args, "want %s (%s)", oid_to_hex(remote),
 759                                      ref->name);
 760                        continue;
 761                }
 762                print_verbose(args, _("already have %s (%s)"), oid_to_hex(remote),
 763                              ref->name);
 764        }
 765
 766        return retval;
 767}
 768
 769static int sideband_demux(int in, int out, void *data)
 770{
 771        int *xd = data;
 772        int ret;
 773
 774        ret = recv_sideband("fetch-pack", xd[0], out);
 775        close(out);
 776        return ret;
 777}
 778
 779static int get_pack(struct fetch_pack_args *args,
 780                    int xd[2], char **pack_lockfile)
 781{
 782        struct async demux;
 783        int do_keep = args->keep_pack;
 784        const char *cmd_name;
 785        struct pack_header header;
 786        int pass_header = 0;
 787        struct child_process cmd = CHILD_PROCESS_INIT;
 788        int ret;
 789
 790        memset(&demux, 0, sizeof(demux));
 791        if (use_sideband) {
 792                /* xd[] is talking with upload-pack; subprocess reads from
 793                 * xd[0], spits out band#2 to stderr, and feeds us band#1
 794                 * through demux->out.
 795                 */
 796                demux.proc = sideband_demux;
 797                demux.data = xd;
 798                demux.out = -1;
 799                demux.isolate_sigpipe = 1;
 800                if (start_async(&demux))
 801                        die(_("fetch-pack: unable to fork off sideband demultiplexer"));
 802        }
 803        else
 804                demux.out = xd[0];
 805
 806        if (!args->keep_pack && unpack_limit) {
 807
 808                if (read_pack_header(demux.out, &header))
 809                        die(_("protocol error: bad pack header"));
 810                pass_header = 1;
 811                if (ntohl(header.hdr_entries) < unpack_limit)
 812                        do_keep = 0;
 813                else
 814                        do_keep = 1;
 815        }
 816
 817        if (alternate_shallow_file) {
 818                argv_array_push(&cmd.args, "--shallow-file");
 819                argv_array_push(&cmd.args, alternate_shallow_file);
 820        }
 821
 822        if (do_keep || args->from_promisor) {
 823                if (pack_lockfile)
 824                        cmd.out = -1;
 825                cmd_name = "index-pack";
 826                argv_array_push(&cmd.args, cmd_name);
 827                argv_array_push(&cmd.args, "--stdin");
 828                if (!args->quiet && !args->no_progress)
 829                        argv_array_push(&cmd.args, "-v");
 830                if (args->use_thin_pack)
 831                        argv_array_push(&cmd.args, "--fix-thin");
 832                if (do_keep && (args->lock_pack || unpack_limit)) {
 833                        char hostname[HOST_NAME_MAX + 1];
 834                        if (xgethostname(hostname, sizeof(hostname)))
 835                                xsnprintf(hostname, sizeof(hostname), "localhost");
 836                        argv_array_pushf(&cmd.args,
 837                                        "--keep=fetch-pack %"PRIuMAX " on %s",
 838                                        (uintmax_t)getpid(), hostname);
 839                }
 840                if (args->check_self_contained_and_connected)
 841                        argv_array_push(&cmd.args, "--check-self-contained-and-connected");
 842                if (args->from_promisor)
 843                        argv_array_push(&cmd.args, "--promisor");
 844        }
 845        else {
 846                cmd_name = "unpack-objects";
 847                argv_array_push(&cmd.args, cmd_name);
 848                if (args->quiet || args->no_progress)
 849                        argv_array_push(&cmd.args, "-q");
 850                args->check_self_contained_and_connected = 0;
 851        }
 852
 853        if (pass_header)
 854                argv_array_pushf(&cmd.args, "--pack_header=%"PRIu32",%"PRIu32,
 855                                 ntohl(header.hdr_version),
 856                                 ntohl(header.hdr_entries));
 857        if (fetch_fsck_objects >= 0
 858            ? fetch_fsck_objects
 859            : transfer_fsck_objects >= 0
 860            ? transfer_fsck_objects
 861            : 0) {
 862                if (args->from_promisor)
 863                        /*
 864                         * We cannot use --strict in index-pack because it
 865                         * checks both broken objects and links, but we only
 866                         * want to check for broken objects.
 867                         */
 868                        argv_array_push(&cmd.args, "--fsck-objects");
 869                else
 870                        argv_array_push(&cmd.args, "--strict");
 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, struct ref *refs)
1282{
1283        process_section_header(reader, "wanted-refs", 0);
1284        while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
1285                struct object_id oid;
1286                const char *end;
1287                struct ref *r = NULL;
1288
1289                if (parse_oid_hex(reader->line, &oid, &end) || *end++ != ' ')
1290                        die(_("expected wanted-ref, got '%s'"), reader->line);
1291
1292                for (r = refs; r; r = r->next) {
1293                        if (!strcmp(end, r->name)) {
1294                                oidcpy(&r->old_oid, &oid);
1295                                break;
1296                        }
1297                }
1298
1299                if (!r)
1300                        die(_("unexpected wanted-ref: '%s'"), reader->line);
1301        }
1302
1303        if (reader->status != PACKET_READ_DELIM)
1304                die(_("error processing wanted refs: %d"), reader->status);
1305}
1306
1307enum fetch_state {
1308        FETCH_CHECK_LOCAL = 0,
1309        FETCH_SEND_REQUEST,
1310        FETCH_PROCESS_ACKS,
1311        FETCH_GET_PACK,
1312        FETCH_DONE,
1313};
1314
1315static struct ref *do_fetch_pack_v2(struct fetch_pack_args *args,
1316                                    int fd[2],
1317                                    const struct ref *orig_ref,
1318                                    struct ref **sought, int nr_sought,
1319                                    char **pack_lockfile)
1320{
1321        struct ref *ref = copy_ref_list(orig_ref);
1322        enum fetch_state state = FETCH_CHECK_LOCAL;
1323        struct oidset common = OIDSET_INIT;
1324        struct packet_reader reader;
1325        int in_vain = 0;
1326        int haves_to_send = INITIAL_FLUSH;
1327        struct fetch_negotiator negotiator;
1328        fetch_negotiator_init(&negotiator, negotiation_algorithm);
1329        packet_reader_init(&reader, fd[0], NULL, 0,
1330                           PACKET_READ_CHOMP_NEWLINE);
1331
1332        while (state != FETCH_DONE) {
1333                switch (state) {
1334                case FETCH_CHECK_LOCAL:
1335                        sort_ref_list(&ref, ref_compare_name);
1336                        QSORT(sought, nr_sought, cmp_ref_by_name);
1337
1338                        /* v2 supports these by default */
1339                        allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
1340                        use_sideband = 2;
1341                        if (args->depth > 0 || args->deepen_since || args->deepen_not)
1342                                args->deepen = 1;
1343
1344                        /* Filter 'ref' by 'sought' and those that aren't local */
1345                        mark_complete_and_common_ref(&negotiator, args, &ref);
1346                        filter_refs(args, &ref, sought, nr_sought);
1347                        if (everything_local(args, &ref))
1348                                state = FETCH_DONE;
1349                        else
1350                                state = FETCH_SEND_REQUEST;
1351
1352                        mark_tips(&negotiator, args->negotiation_tips);
1353                        for_each_cached_alternate(&negotiator,
1354                                                  insert_one_alternate_object);
1355                        break;
1356                case FETCH_SEND_REQUEST:
1357                        if (send_fetch_request(&negotiator, fd[1], args, ref,
1358                                               &common,
1359                                               &haves_to_send, &in_vain))
1360                                state = FETCH_GET_PACK;
1361                        else
1362                                state = FETCH_PROCESS_ACKS;
1363                        break;
1364                case FETCH_PROCESS_ACKS:
1365                        /* Process ACKs/NAKs */
1366                        switch (process_acks(&negotiator, &reader, &common)) {
1367                        case 2:
1368                                state = FETCH_GET_PACK;
1369                                break;
1370                        case 1:
1371                                in_vain = 0;
1372                                /* fallthrough */
1373                        default:
1374                                state = FETCH_SEND_REQUEST;
1375                                break;
1376                        }
1377                        break;
1378                case FETCH_GET_PACK:
1379                        /* Check for shallow-info section */
1380                        if (process_section_header(&reader, "shallow-info", 1))
1381                                receive_shallow_info(args, &reader);
1382
1383                        if (process_section_header(&reader, "wanted-refs", 1))
1384                                receive_wanted_refs(&reader, ref);
1385
1386                        /* get the pack */
1387                        process_section_header(&reader, "packfile", 0);
1388                        if (get_pack(args, fd, pack_lockfile))
1389                                die(_("git fetch-pack: fetch failed."));
1390
1391                        state = FETCH_DONE;
1392                        break;
1393                case FETCH_DONE:
1394                        continue;
1395                }
1396        }
1397
1398        negotiator.release(&negotiator);
1399        oidset_clear(&common);
1400        return ref;
1401}
1402
1403static void fetch_pack_config(void)
1404{
1405        git_config_get_int("fetch.unpacklimit", &fetch_unpack_limit);
1406        git_config_get_int("transfer.unpacklimit", &transfer_unpack_limit);
1407        git_config_get_bool("repack.usedeltabaseoffset", &prefer_ofs_delta);
1408        git_config_get_bool("fetch.fsckobjects", &fetch_fsck_objects);
1409        git_config_get_bool("transfer.fsckobjects", &transfer_fsck_objects);
1410        git_config_get_string("fetch.negotiationalgorithm",
1411                              &negotiation_algorithm);
1412
1413        git_config(git_default_config, NULL);
1414}
1415
1416static void fetch_pack_setup(void)
1417{
1418        static int did_setup;
1419        if (did_setup)
1420                return;
1421        fetch_pack_config();
1422        if (0 <= transfer_unpack_limit)
1423                unpack_limit = transfer_unpack_limit;
1424        else if (0 <= fetch_unpack_limit)
1425                unpack_limit = fetch_unpack_limit;
1426        did_setup = 1;
1427}
1428
1429static int remove_duplicates_in_refs(struct ref **ref, int nr)
1430{
1431        struct string_list names = STRING_LIST_INIT_NODUP;
1432        int src, dst;
1433
1434        for (src = dst = 0; src < nr; src++) {
1435                struct string_list_item *item;
1436                item = string_list_insert(&names, ref[src]->name);
1437                if (item->util)
1438                        continue; /* already have it */
1439                item->util = ref[src];
1440                if (src != dst)
1441                        ref[dst] = ref[src];
1442                dst++;
1443        }
1444        for (src = dst; src < nr; src++)
1445                ref[src] = NULL;
1446        string_list_clear(&names, 0);
1447        return dst;
1448}
1449
1450static void update_shallow(struct fetch_pack_args *args,
1451                           struct ref *refs,
1452                           struct shallow_info *si)
1453{
1454        struct oid_array ref = OID_ARRAY_INIT;
1455        int *status;
1456        int i;
1457        struct ref *r;
1458
1459        if (args->deepen && alternate_shallow_file) {
1460                if (*alternate_shallow_file == '\0') { /* --unshallow */
1461                        unlink_or_warn(git_path_shallow(the_repository));
1462                        rollback_lock_file(&shallow_lock);
1463                } else
1464                        commit_lock_file(&shallow_lock);
1465                return;
1466        }
1467
1468        if (!si->shallow || !si->shallow->nr)
1469                return;
1470
1471        if (args->cloning) {
1472                /*
1473                 * remote is shallow, but this is a clone, there are
1474                 * no objects in repo to worry about. Accept any
1475                 * shallow points that exist in the pack (iow in repo
1476                 * after get_pack() and reprepare_packed_git())
1477                 */
1478                struct oid_array extra = OID_ARRAY_INIT;
1479                struct object_id *oid = si->shallow->oid;
1480                for (i = 0; i < si->shallow->nr; i++)
1481                        if (has_object_file(&oid[i]))
1482                                oid_array_append(&extra, &oid[i]);
1483                if (extra.nr) {
1484                        setup_alternate_shallow(&shallow_lock,
1485                                                &alternate_shallow_file,
1486                                                &extra);
1487                        commit_lock_file(&shallow_lock);
1488                }
1489                oid_array_clear(&extra);
1490                return;
1491        }
1492
1493        if (!si->nr_ours && !si->nr_theirs)
1494                return;
1495
1496        remove_nonexistent_theirs_shallow(si);
1497        if (!si->nr_ours && !si->nr_theirs)
1498                return;
1499        for (r = refs; r; r = r->next)
1500                oid_array_append(&ref, &r->old_oid);
1501        si->ref = &ref;
1502
1503        if (args->update_shallow) {
1504                /*
1505                 * remote is also shallow, .git/shallow may be updated
1506                 * so all refs can be accepted. Make sure we only add
1507                 * shallow roots that are actually reachable from new
1508                 * refs.
1509                 */
1510                struct oid_array extra = OID_ARRAY_INIT;
1511                struct object_id *oid = si->shallow->oid;
1512                assign_shallow_commits_to_refs(si, NULL, NULL);
1513                if (!si->nr_ours && !si->nr_theirs) {
1514                        oid_array_clear(&ref);
1515                        return;
1516                }
1517                for (i = 0; i < si->nr_ours; i++)
1518                        oid_array_append(&extra, &oid[si->ours[i]]);
1519                for (i = 0; i < si->nr_theirs; i++)
1520                        oid_array_append(&extra, &oid[si->theirs[i]]);
1521                setup_alternate_shallow(&shallow_lock,
1522                                        &alternate_shallow_file,
1523                                        &extra);
1524                commit_lock_file(&shallow_lock);
1525                oid_array_clear(&extra);
1526                oid_array_clear(&ref);
1527                return;
1528        }
1529
1530        /*
1531         * remote is also shallow, check what ref is safe to update
1532         * without updating .git/shallow
1533         */
1534        status = xcalloc(ref.nr, sizeof(*status));
1535        assign_shallow_commits_to_refs(si, NULL, status);
1536        if (si->nr_ours || si->nr_theirs) {
1537                for (r = refs, i = 0; r; r = r->next, i++)
1538                        if (status[i])
1539                                r->status = REF_STATUS_REJECT_SHALLOW;
1540        }
1541        free(status);
1542        oid_array_clear(&ref);
1543}
1544
1545static int iterate_ref_map(void *cb_data, struct object_id *oid)
1546{
1547        struct ref **rm = cb_data;
1548        struct ref *ref = *rm;
1549
1550        if (!ref)
1551                return -1; /* end of the list */
1552        *rm = ref->next;
1553        oidcpy(oid, &ref->old_oid);
1554        return 0;
1555}
1556
1557struct ref *fetch_pack(struct fetch_pack_args *args,
1558                       int fd[], struct child_process *conn,
1559                       const struct ref *ref,
1560                       const char *dest,
1561                       struct ref **sought, int nr_sought,
1562                       struct oid_array *shallow,
1563                       char **pack_lockfile,
1564                       enum protocol_version version)
1565{
1566        struct ref *ref_cpy;
1567        struct shallow_info si;
1568
1569        fetch_pack_setup();
1570        if (nr_sought)
1571                nr_sought = remove_duplicates_in_refs(sought, nr_sought);
1572
1573        if (!ref) {
1574                packet_flush(fd[1]);
1575                die(_("no matching remote head"));
1576        }
1577        prepare_shallow_info(&si, shallow);
1578        if (version == protocol_v2)
1579                ref_cpy = do_fetch_pack_v2(args, fd, ref, sought, nr_sought,
1580                                           pack_lockfile);
1581        else
1582                ref_cpy = do_fetch_pack(args, fd, ref, sought, nr_sought,
1583                                        &si, pack_lockfile);
1584        reprepare_packed_git(the_repository);
1585
1586        if (!args->cloning && args->deepen) {
1587                struct check_connected_options opt = CHECK_CONNECTED_INIT;
1588                struct ref *iterator = ref_cpy;
1589                opt.shallow_file = alternate_shallow_file;
1590                if (args->deepen)
1591                        opt.is_deepening_fetch = 1;
1592                if (check_connected(iterate_ref_map, &iterator, &opt)) {
1593                        error(_("remote did not send all necessary objects"));
1594                        free_refs(ref_cpy);
1595                        ref_cpy = NULL;
1596                        rollback_lock_file(&shallow_lock);
1597                        goto cleanup;
1598                }
1599                args->connectivity_checked = 1;
1600        }
1601
1602        update_shallow(args, ref_cpy, &si);
1603cleanup:
1604        clear_shallow_info(&si);
1605        return ref_cpy;
1606}
1607
1608int report_unmatched_refs(struct ref **sought, int nr_sought)
1609{
1610        int i, ret = 0;
1611
1612        for (i = 0; i < nr_sought; i++) {
1613                if (!sought[i])
1614                        continue;
1615                switch (sought[i]->match_status) {
1616                case REF_MATCHED:
1617                        continue;
1618                case REF_NOT_MATCHED:
1619                        error(_("no such remote ref %s"), sought[i]->name);
1620                        break;
1621                case REF_UNADVERTISED_NOT_ALLOWED:
1622                        error(_("Server does not allow request for unadvertised object %s"),
1623                              sought[i]->name);
1624                        break;
1625                }
1626                ret = 1;
1627        }
1628        return ret;
1629}