fetch-pack.con commit transport: drop refnames from for_each_alternate_ref (bdf4276)
   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 struct object_id *oid,
  80                                void *vcache)
  81{
  82        struct alternate_object_cache *cache = vcache;
  83        struct object *obj = parse_object(the_repository, oid);
  84
  85        if (!obj || (obj->flags & ALTERNATE))
  86                return;
  87
  88        obj->flags |= ALTERNATE;
  89        ALLOC_GROW(cache->items, cache->nr + 1, cache->alloc);
  90        cache->items[cache->nr++] = obj;
  91}
  92
  93static void for_each_cached_alternate(struct fetch_negotiator *negotiator,
  94                                      void (*cb)(struct fetch_negotiator *,
  95                                                 struct object *))
  96{
  97        static int initialized;
  98        static struct alternate_object_cache cache;
  99        size_t i;
 100
 101        if (!initialized) {
 102                for_each_alternate_ref(cache_one_alternate, &cache);
 103                initialized = 1;
 104        }
 105
 106        for (i = 0; i < cache.nr; i++)
 107                cb(negotiator, cache.items[i]);
 108}
 109
 110static int rev_list_insert_ref(struct fetch_negotiator *negotiator,
 111                               const char *refname,
 112                               const struct object_id *oid)
 113{
 114        struct object *o = deref_tag(the_repository,
 115                                     parse_object(the_repository, oid),
 116                                     refname, 0);
 117
 118        if (o && o->type == OBJ_COMMIT)
 119                negotiator->add_tip(negotiator, (struct commit *)o);
 120
 121        return 0;
 122}
 123
 124static int rev_list_insert_ref_oid(const char *refname, const struct object_id *oid,
 125                                   int flag, void *cb_data)
 126{
 127        return rev_list_insert_ref(cb_data, refname, oid);
 128}
 129
 130enum ack_type {
 131        NAK = 0,
 132        ACK,
 133        ACK_continue,
 134        ACK_common,
 135        ACK_ready
 136};
 137
 138static void consume_shallow_list(struct fetch_pack_args *args, int fd)
 139{
 140        if (args->stateless_rpc && args->deepen) {
 141                /* If we sent a depth we will get back "duplicate"
 142                 * shallow and unshallow commands every time there
 143                 * is a block of have lines exchanged.
 144                 */
 145                char *line;
 146                while ((line = packet_read_line(fd, NULL))) {
 147                        if (starts_with(line, "shallow "))
 148                                continue;
 149                        if (starts_with(line, "unshallow "))
 150                                continue;
 151                        die(_("git fetch-pack: expected shallow list"));
 152                }
 153        }
 154}
 155
 156static enum ack_type get_ack(int fd, struct object_id *result_oid)
 157{
 158        int len;
 159        char *line = packet_read_line(fd, &len);
 160        const char *arg;
 161
 162        if (!line)
 163                die(_("git fetch-pack: expected ACK/NAK, got a flush packet"));
 164        if (!strcmp(line, "NAK"))
 165                return NAK;
 166        if (skip_prefix(line, "ACK ", &arg)) {
 167                if (!get_oid_hex(arg, result_oid)) {
 168                        arg += 40;
 169                        len -= arg - line;
 170                        if (len < 1)
 171                                return ACK;
 172                        if (strstr(arg, "continue"))
 173                                return ACK_continue;
 174                        if (strstr(arg, "common"))
 175                                return ACK_common;
 176                        if (strstr(arg, "ready"))
 177                                return ACK_ready;
 178                        return ACK;
 179                }
 180        }
 181        if (skip_prefix(line, "ERR ", &arg))
 182                die(_("remote error: %s"), arg);
 183        die(_("git fetch-pack: expected ACK/NAK, got '%s'"), line);
 184}
 185
 186static void send_request(struct fetch_pack_args *args,
 187                         int fd, struct strbuf *buf)
 188{
 189        if (args->stateless_rpc) {
 190                send_sideband(fd, -1, buf->buf, buf->len, LARGE_PACKET_MAX);
 191                packet_flush(fd);
 192        } else
 193                write_or_die(fd, buf->buf, buf->len);
 194}
 195
 196static void insert_one_alternate_object(struct fetch_negotiator *negotiator,
 197                                        struct object *obj)
 198{
 199        rev_list_insert_ref(negotiator, NULL, &obj->oid);
 200}
 201
 202#define INITIAL_FLUSH 16
 203#define PIPESAFE_FLUSH 32
 204#define LARGE_FLUSH 16384
 205
 206static int next_flush(int stateless_rpc, int count)
 207{
 208        if (stateless_rpc) {
 209                if (count < LARGE_FLUSH)
 210                        count <<= 1;
 211                else
 212                        count = count * 11 / 10;
 213        } else {
 214                if (count < PIPESAFE_FLUSH)
 215                        count <<= 1;
 216                else
 217                        count += PIPESAFE_FLUSH;
 218        }
 219        return count;
 220}
 221
 222static void mark_tips(struct fetch_negotiator *negotiator,
 223                      const struct oid_array *negotiation_tips)
 224{
 225        int i;
 226
 227        if (!negotiation_tips) {
 228                for_each_ref(rev_list_insert_ref_oid, negotiator);
 229                return;
 230        }
 231
 232        for (i = 0; i < negotiation_tips->nr; i++)
 233                rev_list_insert_ref(negotiator, NULL,
 234                                    &negotiation_tips->oid[i]);
 235        return;
 236}
 237
 238static int find_common(struct fetch_negotiator *negotiator,
 239                       struct fetch_pack_args *args,
 240                       int fd[2], struct object_id *result_oid,
 241                       struct ref *refs)
 242{
 243        int fetching;
 244        int count = 0, flushes = 0, flush_at = INITIAL_FLUSH, retval;
 245        const struct object_id *oid;
 246        unsigned in_vain = 0;
 247        int got_continue = 0;
 248        int got_ready = 0;
 249        struct strbuf req_buf = STRBUF_INIT;
 250        size_t state_len = 0;
 251
 252        if (args->stateless_rpc && multi_ack == 1)
 253                die(_("--stateless-rpc requires multi_ack_detailed"));
 254
 255        mark_tips(negotiator, args->negotiation_tips);
 256        for_each_cached_alternate(negotiator, insert_one_alternate_object);
 257
 258        fetching = 0;
 259        for ( ; refs ; refs = refs->next) {
 260                struct object_id *remote = &refs->old_oid;
 261                const char *remote_hex;
 262                struct object *o;
 263
 264                /*
 265                 * If that object is complete (i.e. it is an ancestor of a
 266                 * local ref), we tell them we have it but do not have to
 267                 * tell them about its ancestors, which they already know
 268                 * about.
 269                 *
 270                 * We use lookup_object here because we are only
 271                 * interested in the case we *know* the object is
 272                 * reachable and we have already scanned it.
 273                 */
 274                if (((o = lookup_object(the_repository, remote->hash)) != NULL) &&
 275                                (o->flags & COMPLETE)) {
 276                        continue;
 277                }
 278
 279                remote_hex = oid_to_hex(remote);
 280                if (!fetching) {
 281                        struct strbuf c = STRBUF_INIT;
 282                        if (multi_ack == 2)     strbuf_addstr(&c, " multi_ack_detailed");
 283                        if (multi_ack == 1)     strbuf_addstr(&c, " multi_ack");
 284                        if (no_done)            strbuf_addstr(&c, " no-done");
 285                        if (use_sideband == 2)  strbuf_addstr(&c, " side-band-64k");
 286                        if (use_sideband == 1)  strbuf_addstr(&c, " side-band");
 287                        if (args->deepen_relative) strbuf_addstr(&c, " deepen-relative");
 288                        if (args->use_thin_pack) strbuf_addstr(&c, " thin-pack");
 289                        if (args->no_progress)   strbuf_addstr(&c, " no-progress");
 290                        if (args->include_tag)   strbuf_addstr(&c, " include-tag");
 291                        if (prefer_ofs_delta)   strbuf_addstr(&c, " ofs-delta");
 292                        if (deepen_since_ok)    strbuf_addstr(&c, " deepen-since");
 293                        if (deepen_not_ok)      strbuf_addstr(&c, " deepen-not");
 294                        if (agent_supported)    strbuf_addf(&c, " agent=%s",
 295                                                            git_user_agent_sanitized());
 296                        if (args->filter_options.choice)
 297                                strbuf_addstr(&c, " filter");
 298                        packet_buf_write(&req_buf, "want %s%s\n", remote_hex, c.buf);
 299                        strbuf_release(&c);
 300                } else
 301                        packet_buf_write(&req_buf, "want %s\n", remote_hex);
 302                fetching++;
 303        }
 304
 305        if (!fetching) {
 306                strbuf_release(&req_buf);
 307                packet_flush(fd[1]);
 308                return 1;
 309        }
 310
 311        if (is_repository_shallow(the_repository))
 312                write_shallow_commits(&req_buf, 1, NULL);
 313        if (args->depth > 0)
 314                packet_buf_write(&req_buf, "deepen %d", args->depth);
 315        if (args->deepen_since) {
 316                timestamp_t max_age = approxidate(args->deepen_since);
 317                packet_buf_write(&req_buf, "deepen-since %"PRItime, max_age);
 318        }
 319        if (args->deepen_not) {
 320                int i;
 321                for (i = 0; i < args->deepen_not->nr; i++) {
 322                        struct string_list_item *s = args->deepen_not->items + i;
 323                        packet_buf_write(&req_buf, "deepen-not %s", s->string);
 324                }
 325        }
 326        if (server_supports_filtering && args->filter_options.choice)
 327                packet_buf_write(&req_buf, "filter %s",
 328                                 args->filter_options.filter_spec);
 329        packet_buf_flush(&req_buf);
 330        state_len = req_buf.len;
 331
 332        if (args->deepen) {
 333                char *line;
 334                const char *arg;
 335                struct object_id oid;
 336
 337                send_request(args, fd[1], &req_buf);
 338                while ((line = packet_read_line(fd[0], NULL))) {
 339                        if (skip_prefix(line, "shallow ", &arg)) {
 340                                if (get_oid_hex(arg, &oid))
 341                                        die(_("invalid shallow line: %s"), line);
 342                                register_shallow(the_repository, &oid);
 343                                continue;
 344                        }
 345                        if (skip_prefix(line, "unshallow ", &arg)) {
 346                                if (get_oid_hex(arg, &oid))
 347                                        die(_("invalid unshallow line: %s"), line);
 348                                if (!lookup_object(the_repository, oid.hash))
 349                                        die(_("object not found: %s"), line);
 350                                /* make sure that it is parsed as shallow */
 351                                if (!parse_object(the_repository, &oid))
 352                                        die(_("error in object: %s"), line);
 353                                if (unregister_shallow(&oid))
 354                                        die(_("no shallow found: %s"), line);
 355                                continue;
 356                        }
 357                        die(_("expected shallow/unshallow, got %s"), line);
 358                }
 359        } else if (!args->stateless_rpc)
 360                send_request(args, fd[1], &req_buf);
 361
 362        if (!args->stateless_rpc) {
 363                /* If we aren't using the stateless-rpc interface
 364                 * we don't need to retain the headers.
 365                 */
 366                strbuf_setlen(&req_buf, 0);
 367                state_len = 0;
 368        }
 369
 370        flushes = 0;
 371        retval = -1;
 372        if (args->no_dependents)
 373                goto done;
 374        while ((oid = negotiator->next(negotiator))) {
 375                packet_buf_write(&req_buf, "have %s\n", oid_to_hex(oid));
 376                print_verbose(args, "have %s", oid_to_hex(oid));
 377                in_vain++;
 378                if (flush_at <= ++count) {
 379                        int ack;
 380
 381                        packet_buf_flush(&req_buf);
 382                        send_request(args, fd[1], &req_buf);
 383                        strbuf_setlen(&req_buf, state_len);
 384                        flushes++;
 385                        flush_at = next_flush(args->stateless_rpc, count);
 386
 387                        /*
 388                         * We keep one window "ahead" of the other side, and
 389                         * will wait for an ACK only on the next one
 390                         */
 391                        if (!args->stateless_rpc && count == INITIAL_FLUSH)
 392                                continue;
 393
 394                        consume_shallow_list(args, fd[0]);
 395                        do {
 396                                ack = get_ack(fd[0], result_oid);
 397                                if (ack)
 398                                        print_verbose(args, _("got %s %d %s"), "ack",
 399                                                      ack, oid_to_hex(result_oid));
 400                                switch (ack) {
 401                                case ACK:
 402                                        flushes = 0;
 403                                        multi_ack = 0;
 404                                        retval = 0;
 405                                        goto done;
 406                                case ACK_common:
 407                                case ACK_ready:
 408                                case ACK_continue: {
 409                                        struct commit *commit =
 410                                                lookup_commit(the_repository,
 411                                                              result_oid);
 412                                        int was_common;
 413
 414                                        if (!commit)
 415                                                die(_("invalid commit %s"), oid_to_hex(result_oid));
 416                                        was_common = negotiator->ack(negotiator, commit);
 417                                        if (args->stateless_rpc
 418                                         && ack == ACK_common
 419                                         && !was_common) {
 420                                                /* We need to replay the have for this object
 421                                                 * on the next RPC request so the peer knows
 422                                                 * it is in common with us.
 423                                                 */
 424                                                const char *hex = oid_to_hex(result_oid);
 425                                                packet_buf_write(&req_buf, "have %s\n", hex);
 426                                                state_len = req_buf.len;
 427                                                /*
 428                                                 * Reset in_vain because an ack
 429                                                 * for this commit has not been
 430                                                 * seen.
 431                                                 */
 432                                                in_vain = 0;
 433                                        } else if (!args->stateless_rpc
 434                                                   || ack != ACK_common)
 435                                                in_vain = 0;
 436                                        retval = 0;
 437                                        got_continue = 1;
 438                                        if (ack == ACK_ready)
 439                                                got_ready = 1;
 440                                        break;
 441                                        }
 442                                }
 443                        } while (ack);
 444                        flushes--;
 445                        if (got_continue && MAX_IN_VAIN < in_vain) {
 446                                print_verbose(args, _("giving up"));
 447                                break; /* give up */
 448                        }
 449                        if (got_ready)
 450                                break;
 451                }
 452        }
 453done:
 454        if (!got_ready || !no_done) {
 455                packet_buf_write(&req_buf, "done\n");
 456                send_request(args, fd[1], &req_buf);
 457        }
 458        print_verbose(args, _("done"));
 459        if (retval != 0) {
 460                multi_ack = 0;
 461                flushes++;
 462        }
 463        strbuf_release(&req_buf);
 464
 465        if (!got_ready || !no_done)
 466                consume_shallow_list(args, fd[0]);
 467        while (flushes || multi_ack) {
 468                int ack = get_ack(fd[0], result_oid);
 469                if (ack) {
 470                        print_verbose(args, _("got %s (%d) %s"), "ack",
 471                                      ack, oid_to_hex(result_oid));
 472                        if (ack == ACK)
 473                                return 0;
 474                        multi_ack = 1;
 475                        continue;
 476                }
 477                flushes--;
 478        }
 479        /* it is no error to fetch into a completely empty repo */
 480        return count ? retval : 0;
 481}
 482
 483static struct commit_list *complete;
 484
 485static int mark_complete(const struct object_id *oid)
 486{
 487        struct object *o = parse_object(the_repository, oid);
 488
 489        while (o && o->type == OBJ_TAG) {
 490                struct tag *t = (struct tag *) o;
 491                if (!t->tagged)
 492                        break; /* broken repository */
 493                o->flags |= COMPLETE;
 494                o = parse_object(the_repository, &t->tagged->oid);
 495        }
 496        if (o && o->type == OBJ_COMMIT) {
 497                struct commit *commit = (struct commit *)o;
 498                if (!(commit->object.flags & COMPLETE)) {
 499                        commit->object.flags |= COMPLETE;
 500                        commit_list_insert(commit, &complete);
 501                }
 502        }
 503        return 0;
 504}
 505
 506static int mark_complete_oid(const char *refname, const struct object_id *oid,
 507                             int flag, void *cb_data)
 508{
 509        return mark_complete(oid);
 510}
 511
 512static void mark_recent_complete_commits(struct fetch_pack_args *args,
 513                                         timestamp_t cutoff)
 514{
 515        while (complete && cutoff <= complete->item->date) {
 516                print_verbose(args, _("Marking %s as complete"),
 517                              oid_to_hex(&complete->item->object.oid));
 518                pop_most_recent_commit(&complete, COMPLETE);
 519        }
 520}
 521
 522static void add_refs_to_oidset(struct oidset *oids, struct ref *refs)
 523{
 524        for (; refs; refs = refs->next)
 525                oidset_insert(oids, &refs->old_oid);
 526}
 527
 528static int tip_oids_contain(struct oidset *tip_oids,
 529                            struct ref *unmatched, struct ref *newlist,
 530                            const struct object_id *id)
 531{
 532        /*
 533         * Note that this only looks at the ref lists the first time it's
 534         * called. This works out in filter_refs() because even though it may
 535         * add to "newlist" between calls, the additions will always be for
 536         * oids that are already in the set.
 537         */
 538        if (!tip_oids->map.map.tablesize) {
 539                add_refs_to_oidset(tip_oids, unmatched);
 540                add_refs_to_oidset(tip_oids, newlist);
 541        }
 542        return oidset_contains(tip_oids, id);
 543}
 544
 545static void filter_refs(struct fetch_pack_args *args,
 546                        struct ref **refs,
 547                        struct ref **sought, int nr_sought)
 548{
 549        struct ref *newlist = NULL;
 550        struct ref **newtail = &newlist;
 551        struct ref *unmatched = NULL;
 552        struct ref *ref, *next;
 553        struct oidset tip_oids = OIDSET_INIT;
 554        int i;
 555
 556        i = 0;
 557        for (ref = *refs; ref; ref = next) {
 558                int keep = 0;
 559                next = ref->next;
 560
 561                if (starts_with(ref->name, "refs/") &&
 562                    check_refname_format(ref->name, 0))
 563                        ; /* trash */
 564                else {
 565                        while (i < nr_sought) {
 566                                int cmp = strcmp(ref->name, sought[i]->name);
 567                                if (cmp < 0)
 568                                        break; /* definitely do not have it */
 569                                else if (cmp == 0) {
 570                                        keep = 1; /* definitely have it */
 571                                        sought[i]->match_status = REF_MATCHED;
 572                                }
 573                                i++;
 574                        }
 575
 576                        if (!keep && args->fetch_all &&
 577                            (!args->deepen || !starts_with(ref->name, "refs/tags/")))
 578                                keep = 1;
 579                }
 580
 581                if (keep) {
 582                        *newtail = ref;
 583                        ref->next = NULL;
 584                        newtail = &ref->next;
 585                } else {
 586                        ref->next = unmatched;
 587                        unmatched = ref;
 588                }
 589        }
 590
 591        /* Append unmatched requests to the list */
 592        for (i = 0; i < nr_sought; i++) {
 593                struct object_id oid;
 594                const char *p;
 595
 596                ref = sought[i];
 597                if (ref->match_status != REF_NOT_MATCHED)
 598                        continue;
 599                if (parse_oid_hex(ref->name, &oid, &p) ||
 600                    *p != '\0' ||
 601                    oidcmp(&oid, &ref->old_oid))
 602                        continue;
 603
 604                if ((allow_unadvertised_object_request &
 605                     (ALLOW_TIP_SHA1 | ALLOW_REACHABLE_SHA1)) ||
 606                    tip_oids_contain(&tip_oids, unmatched, newlist,
 607                                     &ref->old_oid)) {
 608                        ref->match_status = REF_MATCHED;
 609                        *newtail = copy_ref(ref);
 610                        newtail = &(*newtail)->next;
 611                } else {
 612                        ref->match_status = REF_UNADVERTISED_NOT_ALLOWED;
 613                }
 614        }
 615
 616        oidset_clear(&tip_oids);
 617        for (ref = unmatched; ref; ref = next) {
 618                next = ref->next;
 619                free(ref);
 620        }
 621
 622        *refs = newlist;
 623}
 624
 625static void mark_alternate_complete(struct fetch_negotiator *unused,
 626                                    struct object *obj)
 627{
 628        mark_complete(&obj->oid);
 629}
 630
 631struct loose_object_iter {
 632        struct oidset *loose_object_set;
 633        struct ref *refs;
 634};
 635
 636/*
 637 *  If the number of refs is not larger than the number of loose objects,
 638 *  this function stops inserting.
 639 */
 640static int add_loose_objects_to_set(const struct object_id *oid,
 641                                    const char *path,
 642                                    void *data)
 643{
 644        struct loose_object_iter *iter = data;
 645        oidset_insert(iter->loose_object_set, oid);
 646        if (iter->refs == NULL)
 647                return 1;
 648
 649        iter->refs = iter->refs->next;
 650        return 0;
 651}
 652
 653/*
 654 * Mark recent commits available locally and reachable from a local ref as
 655 * COMPLETE. If args->no_dependents is false, also mark COMPLETE remote refs as
 656 * COMMON_REF (otherwise, we are not planning to participate in negotiation, and
 657 * thus do not need COMMON_REF marks).
 658 *
 659 * The cutoff time for recency is determined by this heuristic: it is the
 660 * earliest commit time of the objects in refs that are commits and that we know
 661 * the commit time of.
 662 */
 663static void mark_complete_and_common_ref(struct fetch_negotiator *negotiator,
 664                                         struct fetch_pack_args *args,
 665                                         struct ref **refs)
 666{
 667        struct ref *ref;
 668        int old_save_commit_buffer = save_commit_buffer;
 669        timestamp_t cutoff = 0;
 670        struct oidset loose_oid_set = OIDSET_INIT;
 671        int use_oidset = 0;
 672        struct loose_object_iter iter = {&loose_oid_set, *refs};
 673
 674        /* Enumerate all loose objects or know refs are not so many. */
 675        use_oidset = !for_each_loose_object(add_loose_objects_to_set,
 676                                            &iter, 0);
 677
 678        save_commit_buffer = 0;
 679
 680        for (ref = *refs; ref; ref = ref->next) {
 681                struct object *o;
 682                unsigned int flags = OBJECT_INFO_QUICK;
 683
 684                if (use_oidset &&
 685                    !oidset_contains(&loose_oid_set, &ref->old_oid)) {
 686                        /*
 687                         * I know this does not exist in the loose form,
 688                         * so check if it exists in a non-loose form.
 689                         */
 690                        flags |= OBJECT_INFO_IGNORE_LOOSE;
 691                }
 692
 693                if (!has_object_file_with_flags(&ref->old_oid, flags))
 694                        continue;
 695                o = parse_object(the_repository, &ref->old_oid);
 696                if (!o)
 697                        continue;
 698
 699                /* We already have it -- which may mean that we were
 700                 * in sync with the other side at some time after
 701                 * that (it is OK if we guess wrong here).
 702                 */
 703                if (o->type == OBJ_COMMIT) {
 704                        struct commit *commit = (struct commit *)o;
 705                        if (!cutoff || cutoff < commit->date)
 706                                cutoff = commit->date;
 707                }
 708        }
 709
 710        oidset_clear(&loose_oid_set);
 711
 712        if (!args->no_dependents) {
 713                if (!args->deepen) {
 714                        for_each_ref(mark_complete_oid, NULL);
 715                        for_each_cached_alternate(NULL, mark_alternate_complete);
 716                        commit_list_sort_by_date(&complete);
 717                        if (cutoff)
 718                                mark_recent_complete_commits(args, cutoff);
 719                }
 720
 721                /*
 722                 * Mark all complete remote refs as common refs.
 723                 * Don't mark them common yet; the server has to be told so first.
 724                 */
 725                for (ref = *refs; ref; ref = ref->next) {
 726                        struct object *o = deref_tag(the_repository,
 727                                                     lookup_object(the_repository,
 728                                                     ref->old_oid.hash),
 729                                                     NULL, 0);
 730
 731                        if (!o || o->type != OBJ_COMMIT || !(o->flags & COMPLETE))
 732                                continue;
 733
 734                        negotiator->known_common(negotiator,
 735                                                 (struct commit *)o);
 736                }
 737        }
 738
 739        save_commit_buffer = old_save_commit_buffer;
 740}
 741
 742/*
 743 * Returns 1 if every object pointed to by the given remote refs is available
 744 * locally and reachable from a local ref, and 0 otherwise.
 745 */
 746static int everything_local(struct fetch_pack_args *args,
 747                            struct ref **refs)
 748{
 749        struct ref *ref;
 750        int retval;
 751
 752        for (retval = 1, ref = *refs; ref ; ref = ref->next) {
 753                const struct object_id *remote = &ref->old_oid;
 754                struct object *o;
 755
 756                o = lookup_object(the_repository, remote->hash);
 757                if (!o || !(o->flags & COMPLETE)) {
 758                        retval = 0;
 759                        print_verbose(args, "want %s (%s)", oid_to_hex(remote),
 760                                      ref->name);
 761                        continue;
 762                }
 763                print_verbose(args, _("already have %s (%s)"), oid_to_hex(remote),
 764                              ref->name);
 765        }
 766
 767        return retval;
 768}
 769
 770static int sideband_demux(int in, int out, void *data)
 771{
 772        int *xd = data;
 773        int ret;
 774
 775        ret = recv_sideband("fetch-pack", xd[0], out);
 776        close(out);
 777        return ret;
 778}
 779
 780static int get_pack(struct fetch_pack_args *args,
 781                    int xd[2], char **pack_lockfile)
 782{
 783        struct async demux;
 784        int do_keep = args->keep_pack;
 785        const char *cmd_name;
 786        struct pack_header header;
 787        int pass_header = 0;
 788        struct child_process cmd = CHILD_PROCESS_INIT;
 789        int ret;
 790
 791        memset(&demux, 0, sizeof(demux));
 792        if (use_sideband) {
 793                /* xd[] is talking with upload-pack; subprocess reads from
 794                 * xd[0], spits out band#2 to stderr, and feeds us band#1
 795                 * through demux->out.
 796                 */
 797                demux.proc = sideband_demux;
 798                demux.data = xd;
 799                demux.out = -1;
 800                demux.isolate_sigpipe = 1;
 801                if (start_async(&demux))
 802                        die(_("fetch-pack: unable to fork off sideband demultiplexer"));
 803        }
 804        else
 805                demux.out = xd[0];
 806
 807        if (!args->keep_pack && unpack_limit) {
 808
 809                if (read_pack_header(demux.out, &header))
 810                        die(_("protocol error: bad pack header"));
 811                pass_header = 1;
 812                if (ntohl(header.hdr_entries) < unpack_limit)
 813                        do_keep = 0;
 814                else
 815                        do_keep = 1;
 816        }
 817
 818        if (alternate_shallow_file) {
 819                argv_array_push(&cmd.args, "--shallow-file");
 820                argv_array_push(&cmd.args, alternate_shallow_file);
 821        }
 822
 823        if (do_keep || args->from_promisor) {
 824                if (pack_lockfile)
 825                        cmd.out = -1;
 826                cmd_name = "index-pack";
 827                argv_array_push(&cmd.args, cmd_name);
 828                argv_array_push(&cmd.args, "--stdin");
 829                if (!args->quiet && !args->no_progress)
 830                        argv_array_push(&cmd.args, "-v");
 831                if (args->use_thin_pack)
 832                        argv_array_push(&cmd.args, "--fix-thin");
 833                if (do_keep && (args->lock_pack || unpack_limit)) {
 834                        char hostname[HOST_NAME_MAX + 1];
 835                        if (xgethostname(hostname, sizeof(hostname)))
 836                                xsnprintf(hostname, sizeof(hostname), "localhost");
 837                        argv_array_pushf(&cmd.args,
 838                                        "--keep=fetch-pack %"PRIuMAX " on %s",
 839                                        (uintmax_t)getpid(), hostname);
 840                }
 841                if (args->check_self_contained_and_connected)
 842                        argv_array_push(&cmd.args, "--check-self-contained-and-connected");
 843                if (args->from_promisor)
 844                        argv_array_push(&cmd.args, "--promisor");
 845        }
 846        else {
 847                cmd_name = "unpack-objects";
 848                argv_array_push(&cmd.args, cmd_name);
 849                if (args->quiet || args->no_progress)
 850                        argv_array_push(&cmd.args, "-q");
 851                args->check_self_contained_and_connected = 0;
 852        }
 853
 854        if (pass_header)
 855                argv_array_pushf(&cmd.args, "--pack_header=%"PRIu32",%"PRIu32,
 856                                 ntohl(header.hdr_version),
 857                                 ntohl(header.hdr_entries));
 858        if (fetch_fsck_objects >= 0
 859            ? fetch_fsck_objects
 860            : transfer_fsck_objects >= 0
 861            ? transfer_fsck_objects
 862            : 0) {
 863                if (args->from_promisor)
 864                        /*
 865                         * We cannot use --strict in index-pack because it
 866                         * checks both broken objects and links, but we only
 867                         * want to check for broken objects.
 868                         */
 869                        argv_array_push(&cmd.args, "--fsck-objects");
 870                else
 871                        argv_array_pushf(&cmd.args, "--strict%s",
 872                                         fsck_msg_types.buf);
 873        }
 874
 875        cmd.in = demux.out;
 876        cmd.git_cmd = 1;
 877        if (start_command(&cmd))
 878                die(_("fetch-pack: unable to fork off %s"), cmd_name);
 879        if (do_keep && pack_lockfile) {
 880                *pack_lockfile = index_pack_lockfile(cmd.out);
 881                close(cmd.out);
 882        }
 883
 884        if (!use_sideband)
 885                /* Closed by start_command() */
 886                xd[0] = -1;
 887
 888        ret = finish_command(&cmd);
 889        if (!ret || (args->check_self_contained_and_connected && ret == 1))
 890                args->self_contained_and_connected =
 891                        args->check_self_contained_and_connected &&
 892                        ret == 0;
 893        else
 894                die(_("%s failed"), cmd_name);
 895        if (use_sideband && finish_async(&demux))
 896                die(_("error in sideband demultiplexer"));
 897        return 0;
 898}
 899
 900static int cmp_ref_by_name(const void *a_, const void *b_)
 901{
 902        const struct ref *a = *((const struct ref **)a_);
 903        const struct ref *b = *((const struct ref **)b_);
 904        return strcmp(a->name, b->name);
 905}
 906
 907static struct ref *do_fetch_pack(struct fetch_pack_args *args,
 908                                 int fd[2],
 909                                 const struct ref *orig_ref,
 910                                 struct ref **sought, int nr_sought,
 911                                 struct shallow_info *si,
 912                                 char **pack_lockfile)
 913{
 914        struct ref *ref = copy_ref_list(orig_ref);
 915        struct object_id oid;
 916        const char *agent_feature;
 917        int agent_len;
 918        struct fetch_negotiator negotiator;
 919        fetch_negotiator_init(&negotiator, negotiation_algorithm);
 920
 921        sort_ref_list(&ref, ref_compare_name);
 922        QSORT(sought, nr_sought, cmp_ref_by_name);
 923
 924        if ((args->depth > 0 || is_repository_shallow(the_repository)) && !server_supports("shallow"))
 925                die(_("Server does not support shallow clients"));
 926        if (args->depth > 0 || args->deepen_since || args->deepen_not)
 927                args->deepen = 1;
 928        if (server_supports("multi_ack_detailed")) {
 929                print_verbose(args, _("Server supports multi_ack_detailed"));
 930                multi_ack = 2;
 931                if (server_supports("no-done")) {
 932                        print_verbose(args, _("Server supports no-done"));
 933                        if (args->stateless_rpc)
 934                                no_done = 1;
 935                }
 936        }
 937        else if (server_supports("multi_ack")) {
 938                print_verbose(args, _("Server supports multi_ack"));
 939                multi_ack = 1;
 940        }
 941        if (server_supports("side-band-64k")) {
 942                print_verbose(args, _("Server supports side-band-64k"));
 943                use_sideband = 2;
 944        }
 945        else if (server_supports("side-band")) {
 946                print_verbose(args, _("Server supports side-band"));
 947                use_sideband = 1;
 948        }
 949        if (server_supports("allow-tip-sha1-in-want")) {
 950                print_verbose(args, _("Server supports allow-tip-sha1-in-want"));
 951                allow_unadvertised_object_request |= ALLOW_TIP_SHA1;
 952        }
 953        if (server_supports("allow-reachable-sha1-in-want")) {
 954                print_verbose(args, _("Server supports allow-reachable-sha1-in-want"));
 955                allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
 956        }
 957        if (!server_supports("thin-pack"))
 958                args->use_thin_pack = 0;
 959        if (!server_supports("no-progress"))
 960                args->no_progress = 0;
 961        if (!server_supports("include-tag"))
 962                args->include_tag = 0;
 963        if (server_supports("ofs-delta"))
 964                print_verbose(args, _("Server supports ofs-delta"));
 965        else
 966                prefer_ofs_delta = 0;
 967
 968        if (server_supports("filter")) {
 969                server_supports_filtering = 1;
 970                print_verbose(args, _("Server supports filter"));
 971        } else if (args->filter_options.choice) {
 972                warning("filtering not recognized by server, ignoring");
 973        }
 974
 975        if ((agent_feature = server_feature_value("agent", &agent_len))) {
 976                agent_supported = 1;
 977                if (agent_len)
 978                        print_verbose(args, _("Server version is %.*s"),
 979                                      agent_len, agent_feature);
 980        }
 981        if (server_supports("deepen-since"))
 982                deepen_since_ok = 1;
 983        else if (args->deepen_since)
 984                die(_("Server does not support --shallow-since"));
 985        if (server_supports("deepen-not"))
 986                deepen_not_ok = 1;
 987        else if (args->deepen_not)
 988                die(_("Server does not support --shallow-exclude"));
 989        if (!server_supports("deepen-relative") && args->deepen_relative)
 990                die(_("Server does not support --deepen"));
 991
 992        mark_complete_and_common_ref(&negotiator, args, &ref);
 993        filter_refs(args, &ref, sought, nr_sought);
 994        if (everything_local(args, &ref)) {
 995                packet_flush(fd[1]);
 996                goto all_done;
 997        }
 998        if (find_common(&negotiator, args, fd, &oid, ref) < 0)
 999                if (!args->keep_pack)
1000                        /* When cloning, it is not unusual to have
1001                         * no common commit.
1002                         */
1003                        warning(_("no common commits"));
1004
1005        if (args->stateless_rpc)
1006                packet_flush(fd[1]);
1007        if (args->deepen)
1008                setup_alternate_shallow(&shallow_lock, &alternate_shallow_file,
1009                                        NULL);
1010        else if (si->nr_ours || si->nr_theirs)
1011                alternate_shallow_file = setup_temporary_shallow(si->shallow);
1012        else
1013                alternate_shallow_file = NULL;
1014        if (get_pack(args, fd, pack_lockfile))
1015                die(_("git fetch-pack: fetch failed."));
1016
1017 all_done:
1018        negotiator.release(&negotiator);
1019        return ref;
1020}
1021
1022static void add_shallow_requests(struct strbuf *req_buf,
1023                                 const struct fetch_pack_args *args)
1024{
1025        if (is_repository_shallow(the_repository))
1026                write_shallow_commits(req_buf, 1, NULL);
1027        if (args->depth > 0)
1028                packet_buf_write(req_buf, "deepen %d", args->depth);
1029        if (args->deepen_since) {
1030                timestamp_t max_age = approxidate(args->deepen_since);
1031                packet_buf_write(req_buf, "deepen-since %"PRItime, max_age);
1032        }
1033        if (args->deepen_not) {
1034                int i;
1035                for (i = 0; i < args->deepen_not->nr; i++) {
1036                        struct string_list_item *s = args->deepen_not->items + i;
1037                        packet_buf_write(req_buf, "deepen-not %s", s->string);
1038                }
1039        }
1040}
1041
1042static void add_wants(const struct ref *wants, struct strbuf *req_buf)
1043{
1044        int use_ref_in_want = server_supports_feature("fetch", "ref-in-want", 0);
1045
1046        for ( ; wants ; wants = wants->next) {
1047                const struct object_id *remote = &wants->old_oid;
1048                struct object *o;
1049
1050                /*
1051                 * If that object is complete (i.e. it is an ancestor of a
1052                 * local ref), we tell them we have it but do not have to
1053                 * tell them about its ancestors, which they already know
1054                 * about.
1055                 *
1056                 * We use lookup_object here because we are only
1057                 * interested in the case we *know* the object is
1058                 * reachable and we have already scanned it.
1059                 */
1060                if (((o = lookup_object(the_repository, remote->hash)) != NULL) &&
1061                    (o->flags & COMPLETE)) {
1062                        continue;
1063                }
1064
1065                if (!use_ref_in_want || wants->exact_oid)
1066                        packet_buf_write(req_buf, "want %s\n", oid_to_hex(remote));
1067                else
1068                        packet_buf_write(req_buf, "want-ref %s\n", wants->name);
1069        }
1070}
1071
1072static void add_common(struct strbuf *req_buf, struct oidset *common)
1073{
1074        struct oidset_iter iter;
1075        const struct object_id *oid;
1076        oidset_iter_init(common, &iter);
1077
1078        while ((oid = oidset_iter_next(&iter))) {
1079                packet_buf_write(req_buf, "have %s\n", oid_to_hex(oid));
1080        }
1081}
1082
1083static int add_haves(struct fetch_negotiator *negotiator,
1084                     struct strbuf *req_buf,
1085                     int *haves_to_send, int *in_vain)
1086{
1087        int ret = 0;
1088        int haves_added = 0;
1089        const struct object_id *oid;
1090
1091        while ((oid = negotiator->next(negotiator))) {
1092                packet_buf_write(req_buf, "have %s\n", oid_to_hex(oid));
1093                if (++haves_added >= *haves_to_send)
1094                        break;
1095        }
1096
1097        *in_vain += haves_added;
1098        if (!haves_added || *in_vain >= MAX_IN_VAIN) {
1099                /* Send Done */
1100                packet_buf_write(req_buf, "done\n");
1101                ret = 1;
1102        }
1103
1104        /* Increase haves to send on next round */
1105        *haves_to_send = next_flush(1, *haves_to_send);
1106
1107        return ret;
1108}
1109
1110static int send_fetch_request(struct fetch_negotiator *negotiator, int fd_out,
1111                              const struct fetch_pack_args *args,
1112                              const struct ref *wants, struct oidset *common,
1113                              int *haves_to_send, int *in_vain)
1114{
1115        int ret = 0;
1116        struct strbuf req_buf = STRBUF_INIT;
1117
1118        if (server_supports_v2("fetch", 1))
1119                packet_buf_write(&req_buf, "command=fetch");
1120        if (server_supports_v2("agent", 0))
1121                packet_buf_write(&req_buf, "agent=%s", git_user_agent_sanitized());
1122        if (args->server_options && args->server_options->nr &&
1123            server_supports_v2("server-option", 1)) {
1124                int i;
1125                for (i = 0; i < args->server_options->nr; i++)
1126                        packet_write_fmt(fd_out, "server-option=%s",
1127                                         args->server_options->items[i].string);
1128        }
1129
1130        packet_buf_delim(&req_buf);
1131        if (args->use_thin_pack)
1132                packet_buf_write(&req_buf, "thin-pack");
1133        if (args->no_progress)
1134                packet_buf_write(&req_buf, "no-progress");
1135        if (args->include_tag)
1136                packet_buf_write(&req_buf, "include-tag");
1137        if (prefer_ofs_delta)
1138                packet_buf_write(&req_buf, "ofs-delta");
1139
1140        /* Add shallow-info and deepen request */
1141        if (server_supports_feature("fetch", "shallow", 0))
1142                add_shallow_requests(&req_buf, args);
1143        else if (is_repository_shallow(the_repository) || args->deepen)
1144                die(_("Server does not support shallow requests"));
1145
1146        /* Add filter */
1147        if (server_supports_feature("fetch", "filter", 0) &&
1148            args->filter_options.choice) {
1149                print_verbose(args, _("Server supports filter"));
1150                packet_buf_write(&req_buf, "filter %s",
1151                                 args->filter_options.filter_spec);
1152        } else if (args->filter_options.choice) {
1153                warning("filtering not recognized by server, ignoring");
1154        }
1155
1156        /* add wants */
1157        add_wants(wants, &req_buf);
1158
1159        if (args->no_dependents) {
1160                packet_buf_write(&req_buf, "done");
1161                ret = 1;
1162        } else {
1163                /* Add all of the common commits we've found in previous rounds */
1164                add_common(&req_buf, common);
1165
1166                /* Add initial haves */
1167                ret = add_haves(negotiator, &req_buf, haves_to_send, in_vain);
1168        }
1169
1170        /* Send request */
1171        packet_buf_flush(&req_buf);
1172        write_or_die(fd_out, req_buf.buf, req_buf.len);
1173
1174        strbuf_release(&req_buf);
1175        return ret;
1176}
1177
1178/*
1179 * Processes a section header in a server's response and checks if it matches
1180 * `section`.  If the value of `peek` is 1, the header line will be peeked (and
1181 * not consumed); if 0, the line will be consumed and the function will die if
1182 * the section header doesn't match what was expected.
1183 */
1184static int process_section_header(struct packet_reader *reader,
1185                                  const char *section, int peek)
1186{
1187        int ret;
1188
1189        if (packet_reader_peek(reader) != PACKET_READ_NORMAL)
1190                die(_("error reading section header '%s'"), section);
1191
1192        ret = !strcmp(reader->line, section);
1193
1194        if (!peek) {
1195                if (!ret)
1196                        die(_("expected '%s', received '%s'"),
1197                            section, reader->line);
1198                packet_reader_read(reader);
1199        }
1200
1201        return ret;
1202}
1203
1204static int process_acks(struct fetch_negotiator *negotiator,
1205                        struct packet_reader *reader,
1206                        struct oidset *common)
1207{
1208        /* received */
1209        int received_ready = 0;
1210        int received_ack = 0;
1211
1212        process_section_header(reader, "acknowledgments", 0);
1213        while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
1214                const char *arg;
1215
1216                if (!strcmp(reader->line, "NAK"))
1217                        continue;
1218
1219                if (skip_prefix(reader->line, "ACK ", &arg)) {
1220                        struct object_id oid;
1221                        if (!get_oid_hex(arg, &oid)) {
1222                                struct commit *commit;
1223                                oidset_insert(common, &oid);
1224                                commit = lookup_commit(the_repository, &oid);
1225                                negotiator->ack(negotiator, commit);
1226                        }
1227                        continue;
1228                }
1229
1230                if (!strcmp(reader->line, "ready")) {
1231                        received_ready = 1;
1232                        continue;
1233                }
1234
1235                die(_("unexpected acknowledgment line: '%s'"), reader->line);
1236        }
1237
1238        if (reader->status != PACKET_READ_FLUSH &&
1239            reader->status != PACKET_READ_DELIM)
1240                die(_("error processing acks: %d"), reader->status);
1241
1242        /* return 0 if no common, 1 if there are common, or 2 if ready */
1243        return received_ready ? 2 : (received_ack ? 1 : 0);
1244}
1245
1246static void receive_shallow_info(struct fetch_pack_args *args,
1247                                 struct packet_reader *reader)
1248{
1249        process_section_header(reader, "shallow-info", 0);
1250        while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
1251                const char *arg;
1252                struct object_id oid;
1253
1254                if (skip_prefix(reader->line, "shallow ", &arg)) {
1255                        if (get_oid_hex(arg, &oid))
1256                                die(_("invalid shallow line: %s"), reader->line);
1257                        register_shallow(the_repository, &oid);
1258                        continue;
1259                }
1260                if (skip_prefix(reader->line, "unshallow ", &arg)) {
1261                        if (get_oid_hex(arg, &oid))
1262                                die(_("invalid unshallow line: %s"), reader->line);
1263                        if (!lookup_object(the_repository, oid.hash))
1264                                die(_("object not found: %s"), reader->line);
1265                        /* make sure that it is parsed as shallow */
1266                        if (!parse_object(the_repository, &oid))
1267                                die(_("error in object: %s"), reader->line);
1268                        if (unregister_shallow(&oid))
1269                                die(_("no shallow found: %s"), reader->line);
1270                        continue;
1271                }
1272                die(_("expected shallow/unshallow, got %s"), reader->line);
1273        }
1274
1275        if (reader->status != PACKET_READ_FLUSH &&
1276            reader->status != PACKET_READ_DELIM)
1277                die(_("error processing shallow info: %d"), reader->status);
1278
1279        setup_alternate_shallow(&shallow_lock, &alternate_shallow_file, NULL);
1280        args->deepen = 1;
1281}
1282
1283static void receive_wanted_refs(struct packet_reader *reader,
1284                                struct ref **sought, int nr_sought)
1285{
1286        process_section_header(reader, "wanted-refs", 0);
1287        while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
1288                struct object_id oid;
1289                const char *end;
1290                int i;
1291
1292                if (parse_oid_hex(reader->line, &oid, &end) || *end++ != ' ')
1293                        die(_("expected wanted-ref, got '%s'"), reader->line);
1294
1295                for (i = 0; i < nr_sought; i++) {
1296                        if (!strcmp(end, sought[i]->name)) {
1297                                oidcpy(&sought[i]->old_oid, &oid);
1298                                break;
1299                        }
1300                }
1301
1302                if (i == nr_sought)
1303                        die(_("unexpected wanted-ref: '%s'"), reader->line);
1304        }
1305
1306        if (reader->status != PACKET_READ_DELIM)
1307                die(_("error processing wanted refs: %d"), reader->status);
1308}
1309
1310enum fetch_state {
1311        FETCH_CHECK_LOCAL = 0,
1312        FETCH_SEND_REQUEST,
1313        FETCH_PROCESS_ACKS,
1314        FETCH_GET_PACK,
1315        FETCH_DONE,
1316};
1317
1318static struct ref *do_fetch_pack_v2(struct fetch_pack_args *args,
1319                                    int fd[2],
1320                                    const struct ref *orig_ref,
1321                                    struct ref **sought, int nr_sought,
1322                                    char **pack_lockfile)
1323{
1324        struct ref *ref = copy_ref_list(orig_ref);
1325        enum fetch_state state = FETCH_CHECK_LOCAL;
1326        struct oidset common = OIDSET_INIT;
1327        struct packet_reader reader;
1328        int in_vain = 0;
1329        int haves_to_send = INITIAL_FLUSH;
1330        struct fetch_negotiator negotiator;
1331        fetch_negotiator_init(&negotiator, negotiation_algorithm);
1332        packet_reader_init(&reader, fd[0], NULL, 0,
1333                           PACKET_READ_CHOMP_NEWLINE);
1334
1335        while (state != FETCH_DONE) {
1336                switch (state) {
1337                case FETCH_CHECK_LOCAL:
1338                        sort_ref_list(&ref, ref_compare_name);
1339                        QSORT(sought, nr_sought, cmp_ref_by_name);
1340
1341                        /* v2 supports these by default */
1342                        allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
1343                        use_sideband = 2;
1344                        if (args->depth > 0 || args->deepen_since || args->deepen_not)
1345                                args->deepen = 1;
1346
1347                        /* Filter 'ref' by 'sought' and those that aren't local */
1348                        mark_complete_and_common_ref(&negotiator, args, &ref);
1349                        filter_refs(args, &ref, sought, nr_sought);
1350                        if (everything_local(args, &ref))
1351                                state = FETCH_DONE;
1352                        else
1353                                state = FETCH_SEND_REQUEST;
1354
1355                        mark_tips(&negotiator, args->negotiation_tips);
1356                        for_each_cached_alternate(&negotiator,
1357                                                  insert_one_alternate_object);
1358                        break;
1359                case FETCH_SEND_REQUEST:
1360                        if (send_fetch_request(&negotiator, fd[1], args, ref,
1361                                               &common,
1362                                               &haves_to_send, &in_vain))
1363                                state = FETCH_GET_PACK;
1364                        else
1365                                state = FETCH_PROCESS_ACKS;
1366                        break;
1367                case FETCH_PROCESS_ACKS:
1368                        /* Process ACKs/NAKs */
1369                        switch (process_acks(&negotiator, &reader, &common)) {
1370                        case 2:
1371                                state = FETCH_GET_PACK;
1372                                break;
1373                        case 1:
1374                                in_vain = 0;
1375                                /* fallthrough */
1376                        default:
1377                                state = FETCH_SEND_REQUEST;
1378                                break;
1379                        }
1380                        break;
1381                case FETCH_GET_PACK:
1382                        /* Check for shallow-info section */
1383                        if (process_section_header(&reader, "shallow-info", 1))
1384                                receive_shallow_info(args, &reader);
1385
1386                        if (process_section_header(&reader, "wanted-refs", 1))
1387                                receive_wanted_refs(&reader, sought, nr_sought);
1388
1389                        /* get the pack */
1390                        process_section_header(&reader, "packfile", 0);
1391                        if (get_pack(args, fd, pack_lockfile))
1392                                die(_("git fetch-pack: fetch failed."));
1393
1394                        state = FETCH_DONE;
1395                        break;
1396                case FETCH_DONE:
1397                        continue;
1398                }
1399        }
1400
1401        negotiator.release(&negotiator);
1402        oidset_clear(&common);
1403        return ref;
1404}
1405
1406static int fetch_pack_config_cb(const char *var, const char *value, void *cb)
1407{
1408        if (strcmp(var, "fetch.fsck.skiplist") == 0) {
1409                const char *path;
1410
1411                if (git_config_pathname(&path, var, value))
1412                        return 1;
1413                strbuf_addf(&fsck_msg_types, "%cskiplist=%s",
1414                        fsck_msg_types.len ? ',' : '=', path);
1415                free((char *)path);
1416                return 0;
1417        }
1418
1419        if (skip_prefix(var, "fetch.fsck.", &var)) {
1420                if (is_valid_msg_type(var, value))
1421                        strbuf_addf(&fsck_msg_types, "%c%s=%s",
1422                                fsck_msg_types.len ? ',' : '=', var, value);
1423                else
1424                        warning("Skipping unknown msg id '%s'", var);
1425                return 0;
1426        }
1427
1428        return git_default_config(var, value, cb);
1429}
1430
1431static void fetch_pack_config(void)
1432{
1433        git_config_get_int("fetch.unpacklimit", &fetch_unpack_limit);
1434        git_config_get_int("transfer.unpacklimit", &transfer_unpack_limit);
1435        git_config_get_bool("repack.usedeltabaseoffset", &prefer_ofs_delta);
1436        git_config_get_bool("fetch.fsckobjects", &fetch_fsck_objects);
1437        git_config_get_bool("transfer.fsckobjects", &transfer_fsck_objects);
1438        git_config_get_string("fetch.negotiationalgorithm",
1439                              &negotiation_algorithm);
1440
1441        git_config(fetch_pack_config_cb, NULL);
1442}
1443
1444static void fetch_pack_setup(void)
1445{
1446        static int did_setup;
1447        if (did_setup)
1448                return;
1449        fetch_pack_config();
1450        if (0 <= transfer_unpack_limit)
1451                unpack_limit = transfer_unpack_limit;
1452        else if (0 <= fetch_unpack_limit)
1453                unpack_limit = fetch_unpack_limit;
1454        did_setup = 1;
1455}
1456
1457static int remove_duplicates_in_refs(struct ref **ref, int nr)
1458{
1459        struct string_list names = STRING_LIST_INIT_NODUP;
1460        int src, dst;
1461
1462        for (src = dst = 0; src < nr; src++) {
1463                struct string_list_item *item;
1464                item = string_list_insert(&names, ref[src]->name);
1465                if (item->util)
1466                        continue; /* already have it */
1467                item->util = ref[src];
1468                if (src != dst)
1469                        ref[dst] = ref[src];
1470                dst++;
1471        }
1472        for (src = dst; src < nr; src++)
1473                ref[src] = NULL;
1474        string_list_clear(&names, 0);
1475        return dst;
1476}
1477
1478static void update_shallow(struct fetch_pack_args *args,
1479                           struct ref **sought, int nr_sought,
1480                           struct shallow_info *si)
1481{
1482        struct oid_array ref = OID_ARRAY_INIT;
1483        int *status;
1484        int i;
1485
1486        if (args->deepen && alternate_shallow_file) {
1487                if (*alternate_shallow_file == '\0') { /* --unshallow */
1488                        unlink_or_warn(git_path_shallow(the_repository));
1489                        rollback_lock_file(&shallow_lock);
1490                } else
1491                        commit_lock_file(&shallow_lock);
1492                return;
1493        }
1494
1495        if (!si->shallow || !si->shallow->nr)
1496                return;
1497
1498        if (args->cloning) {
1499                /*
1500                 * remote is shallow, but this is a clone, there are
1501                 * no objects in repo to worry about. Accept any
1502                 * shallow points that exist in the pack (iow in repo
1503                 * after get_pack() and reprepare_packed_git())
1504                 */
1505                struct oid_array extra = OID_ARRAY_INIT;
1506                struct object_id *oid = si->shallow->oid;
1507                for (i = 0; i < si->shallow->nr; i++)
1508                        if (has_object_file(&oid[i]))
1509                                oid_array_append(&extra, &oid[i]);
1510                if (extra.nr) {
1511                        setup_alternate_shallow(&shallow_lock,
1512                                                &alternate_shallow_file,
1513                                                &extra);
1514                        commit_lock_file(&shallow_lock);
1515                }
1516                oid_array_clear(&extra);
1517                return;
1518        }
1519
1520        if (!si->nr_ours && !si->nr_theirs)
1521                return;
1522
1523        remove_nonexistent_theirs_shallow(si);
1524        if (!si->nr_ours && !si->nr_theirs)
1525                return;
1526        for (i = 0; i < nr_sought; i++)
1527                oid_array_append(&ref, &sought[i]->old_oid);
1528        si->ref = &ref;
1529
1530        if (args->update_shallow) {
1531                /*
1532                 * remote is also shallow, .git/shallow may be updated
1533                 * so all refs can be accepted. Make sure we only add
1534                 * shallow roots that are actually reachable from new
1535                 * refs.
1536                 */
1537                struct oid_array extra = OID_ARRAY_INIT;
1538                struct object_id *oid = si->shallow->oid;
1539                assign_shallow_commits_to_refs(si, NULL, NULL);
1540                if (!si->nr_ours && !si->nr_theirs) {
1541                        oid_array_clear(&ref);
1542                        return;
1543                }
1544                for (i = 0; i < si->nr_ours; i++)
1545                        oid_array_append(&extra, &oid[si->ours[i]]);
1546                for (i = 0; i < si->nr_theirs; i++)
1547                        oid_array_append(&extra, &oid[si->theirs[i]]);
1548                setup_alternate_shallow(&shallow_lock,
1549                                        &alternate_shallow_file,
1550                                        &extra);
1551                commit_lock_file(&shallow_lock);
1552                oid_array_clear(&extra);
1553                oid_array_clear(&ref);
1554                return;
1555        }
1556
1557        /*
1558         * remote is also shallow, check what ref is safe to update
1559         * without updating .git/shallow
1560         */
1561        status = xcalloc(nr_sought, sizeof(*status));
1562        assign_shallow_commits_to_refs(si, NULL, status);
1563        if (si->nr_ours || si->nr_theirs) {
1564                for (i = 0; i < nr_sought; i++)
1565                        if (status[i])
1566                                sought[i]->status = REF_STATUS_REJECT_SHALLOW;
1567        }
1568        free(status);
1569        oid_array_clear(&ref);
1570}
1571
1572static int iterate_ref_map(void *cb_data, struct object_id *oid)
1573{
1574        struct ref **rm = cb_data;
1575        struct ref *ref = *rm;
1576
1577        if (!ref)
1578                return -1; /* end of the list */
1579        *rm = ref->next;
1580        oidcpy(oid, &ref->old_oid);
1581        return 0;
1582}
1583
1584struct ref *fetch_pack(struct fetch_pack_args *args,
1585                       int fd[], struct child_process *conn,
1586                       const struct ref *ref,
1587                       const char *dest,
1588                       struct ref **sought, int nr_sought,
1589                       struct oid_array *shallow,
1590                       char **pack_lockfile,
1591                       enum protocol_version version)
1592{
1593        struct ref *ref_cpy;
1594        struct shallow_info si;
1595
1596        fetch_pack_setup();
1597        if (nr_sought)
1598                nr_sought = remove_duplicates_in_refs(sought, nr_sought);
1599
1600        if (!ref) {
1601                packet_flush(fd[1]);
1602                die(_("no matching remote head"));
1603        }
1604        prepare_shallow_info(&si, shallow);
1605        if (version == protocol_v2)
1606                ref_cpy = do_fetch_pack_v2(args, fd, ref, sought, nr_sought,
1607                                           pack_lockfile);
1608        else
1609                ref_cpy = do_fetch_pack(args, fd, ref, sought, nr_sought,
1610                                        &si, pack_lockfile);
1611        reprepare_packed_git(the_repository);
1612
1613        if (!args->cloning && args->deepen) {
1614                struct check_connected_options opt = CHECK_CONNECTED_INIT;
1615                struct ref *iterator = ref_cpy;
1616                opt.shallow_file = alternate_shallow_file;
1617                if (args->deepen)
1618                        opt.is_deepening_fetch = 1;
1619                if (check_connected(iterate_ref_map, &iterator, &opt)) {
1620                        error(_("remote did not send all necessary objects"));
1621                        free_refs(ref_cpy);
1622                        ref_cpy = NULL;
1623                        rollback_lock_file(&shallow_lock);
1624                        goto cleanup;
1625                }
1626                args->connectivity_checked = 1;
1627        }
1628
1629        update_shallow(args, sought, nr_sought, &si);
1630cleanup:
1631        clear_shallow_info(&si);
1632        return ref_cpy;
1633}
1634
1635int report_unmatched_refs(struct ref **sought, int nr_sought)
1636{
1637        int i, ret = 0;
1638
1639        for (i = 0; i < nr_sought; i++) {
1640                if (!sought[i])
1641                        continue;
1642                switch (sought[i]->match_status) {
1643                case REF_MATCHED:
1644                        continue;
1645                case REF_NOT_MATCHED:
1646                        error(_("no such remote ref %s"), sought[i]->name);
1647                        break;
1648                case REF_UNADVERTISED_NOT_ALLOWED:
1649                        error(_("Server does not allow request for unadvertised object %s"),
1650                              sought[i]->name);
1651                        break;
1652                }
1653                ret = 1;
1654        }
1655        return ret;
1656}