Andrew's git - gitweb.git/blob

   1#include "cache.h"
   2#include "config.h"
   3#include "dir.h"
   4#include "git-compat-util.h"
   5#include "lockfile.h"
   6#include "pack.h"
   7#include "packfile.h"
   8#include "commit.h"
   9#include "object.h"
  10#include "refs.h"
  11#include "revision.h"
  12#include "sha1-lookup.h"
  13#include "commit-graph.h"
  14#include "object-store.h"
  15#include "alloc.h"
  16#include "hashmap.h"
  17#include "replace-object.h"
  18#include "progress.h"
  19
  20#define GRAPH_SIGNATURE 0x43475048 /* "CGPH" */
  21#define GRAPH_CHUNKID_OIDFANOUT 0x4f494446 /* "OIDF" */
  22#define GRAPH_CHUNKID_OIDLOOKUP 0x4f49444c /* "OIDL" */
  23#define GRAPH_CHUNKID_DATA 0x43444154 /* "CDAT" */
  24#define GRAPH_CHUNKID_EXTRAEDGES 0x45444745 /* "EDGE" */
  25#define GRAPH_CHUNKID_BASE 0x42415345 /* "BASE" */
  26
  27#define GRAPH_DATA_WIDTH (the_hash_algo->rawsz + 16)
  28
  29#define GRAPH_VERSION_1 0x1
  30#define GRAPH_VERSION GRAPH_VERSION_1
  31
  32#define GRAPH_EXTRA_EDGES_NEEDED 0x80000000
  33#define GRAPH_EDGE_LAST_MASK 0x7fffffff
  34#define GRAPH_PARENT_NONE 0x70000000
  35
  36#define GRAPH_LAST_EDGE 0x80000000
  37
  38#define GRAPH_HEADER_SIZE 8
  39#define GRAPH_FANOUT_SIZE (4 * 256)
  40#define GRAPH_CHUNKLOOKUP_WIDTH 12
  41#define GRAPH_MIN_SIZE (GRAPH_HEADER_SIZE + 4 * GRAPH_CHUNKLOOKUP_WIDTH \
  42                        + GRAPH_FANOUT_SIZE + the_hash_algo->rawsz)
  43
  44char *get_commit_graph_filename(const char *obj_dir)
  45{
  46        char *filename = xstrfmt("%s/info/commit-graph", obj_dir);
  47        char *normalized = xmalloc(strlen(filename) + 1);
  48        normalize_path_copy(normalized, filename);
  49        free(filename);
  50        return normalized;
  51}
  52
  53static char *get_split_graph_filename(const char *obj_dir,
  54                                      const char *oid_hex)
  55{
  56        char *filename = xstrfmt("%s/info/commit-graphs/graph-%s.graph",
  57                                 obj_dir,
  58                                 oid_hex);
  59        char *normalized = xmalloc(strlen(filename) + 1);
  60        normalize_path_copy(normalized, filename);
  61        free(filename);
  62        return normalized;
  63}
  64
  65static char *get_chain_filename(const char *obj_dir)
  66{
  67        return xstrfmt("%s/info/commit-graphs/commit-graph-chain", obj_dir);
  68}
  69
  70static uint8_t oid_version(void)
  71{
  72        return 1;
  73}
  74
  75static struct commit_graph *alloc_commit_graph(void)
  76{
  77        struct commit_graph *g = xcalloc(1, sizeof(*g));
  78        g->graph_fd = -1;
  79
  80        return g;
  81}
  82
  83extern int read_replace_refs;
  84
  85static int commit_graph_compatible(struct repository *r)
  86{
  87        if (!r->gitdir)
  88                return 0;
  89
  90        if (read_replace_refs) {
  91                prepare_replace_object(r);
  92                if (hashmap_get_size(&r->objects->replace_map->map))
  93                        return 0;
  94        }
  95
  96        prepare_commit_graft(r);
  97        if (r->parsed_objects && r->parsed_objects->grafts_nr)
  98                return 0;
  99        if (is_repository_shallow(r))
 100                return 0;
 101
 102        return 1;
 103}
 104
 105int open_commit_graph(const char *graph_file, int *fd, struct stat *st)
 106{
 107        *fd = git_open(graph_file);
 108        if (*fd < 0)
 109                return 0;
 110        if (fstat(*fd, st)) {
 111                close(*fd);
 112                return 0;
 113        }
 114        return 1;
 115}
 116
 117struct commit_graph *load_commit_graph_one_fd_st(int fd, struct stat *st)
 118{
 119        void *graph_map;
 120        size_t graph_size;
 121        struct commit_graph *ret;
 122
 123        graph_size = xsize_t(st->st_size);
 124
 125        if (graph_size < GRAPH_MIN_SIZE) {
 126                close(fd);
 127                error(_("commit-graph file is too small"));
 128                return NULL;
 129        }
 130        graph_map = xmmap(NULL, graph_size, PROT_READ, MAP_PRIVATE, fd, 0);
 131        ret = parse_commit_graph(graph_map, fd, graph_size);
 132
 133        if (!ret) {
 134                munmap(graph_map, graph_size);
 135                close(fd);
 136        }
 137
 138        return ret;
 139}
 140
 141static int verify_commit_graph_lite(struct commit_graph *g)
 142{
 143        /*
 144         * Basic validation shared between parse_commit_graph()
 145         * which'll be called every time the graph is used, and the
 146         * much more expensive verify_commit_graph() used by
 147         * "commit-graph verify".
 148         *
 149         * There should only be very basic checks here to ensure that
 150         * we don't e.g. segfault in fill_commit_in_graph(), but
 151         * because this is a very hot codepath nothing that e.g. loops
 152         * over g->num_commits, or runs a checksum on the commit-graph
 153         * itself.
 154         */
 155        if (!g->chunk_oid_fanout) {
 156                error("commit-graph is missing the OID Fanout chunk");
 157                return 1;
 158        }
 159        if (!g->chunk_oid_lookup) {
 160                error("commit-graph is missing the OID Lookup chunk");
 161                return 1;
 162        }
 163        if (!g->chunk_commit_data) {
 164                error("commit-graph is missing the Commit Data chunk");
 165                return 1;
 166        }
 167
 168        return 0;
 169}
 170
 171struct commit_graph *parse_commit_graph(void *graph_map, int fd,
 172                                        size_t graph_size)
 173{
 174        const unsigned char *data, *chunk_lookup;
 175        uint32_t i;
 176        struct commit_graph *graph;
 177        uint64_t last_chunk_offset;
 178        uint32_t last_chunk_id;
 179        uint32_t graph_signature;
 180        unsigned char graph_version, hash_version;
 181
 182        if (!graph_map)
 183                return NULL;
 184
 185        if (graph_size < GRAPH_MIN_SIZE)
 186                return NULL;
 187
 188        data = (const unsigned char *)graph_map;
 189
 190        graph_signature = get_be32(data);
 191        if (graph_signature != GRAPH_SIGNATURE) {
 192                error(_("commit-graph signature %X does not match signature %X"),
 193                      graph_signature, GRAPH_SIGNATURE);
 194                return NULL;
 195        }
 196
 197        graph_version = *(unsigned char*)(data + 4);
 198        if (graph_version != GRAPH_VERSION) {
 199                error(_("commit-graph version %X does not match version %X"),
 200                      graph_version, GRAPH_VERSION);
 201                return NULL;
 202        }
 203
 204        hash_version = *(unsigned char*)(data + 5);
 205        if (hash_version != oid_version()) {
 206                error(_("commit-graph hash version %X does not match version %X"),
 207                      hash_version, oid_version());
 208                return NULL;
 209        }
 210
 211        graph = alloc_commit_graph();
 212
 213        graph->hash_len = the_hash_algo->rawsz;
 214        graph->num_chunks = *(unsigned char*)(data + 6);
 215        graph->graph_fd = fd;
 216        graph->data = graph_map;
 217        graph->data_len = graph_size;
 218
 219        last_chunk_id = 0;
 220        last_chunk_offset = 8;
 221        chunk_lookup = data + 8;
 222        for (i = 0; i < graph->num_chunks; i++) {
 223                uint32_t chunk_id;
 224                uint64_t chunk_offset;
 225                int chunk_repeated = 0;
 226
 227                if (data + graph_size - chunk_lookup <
 228                    GRAPH_CHUNKLOOKUP_WIDTH) {
 229                        error(_("commit-graph chunk lookup table entry missing; file may be incomplete"));
 230                        free(graph);
 231                        return NULL;
 232                }
 233
 234                chunk_id = get_be32(chunk_lookup + 0);
 235                chunk_offset = get_be64(chunk_lookup + 4);
 236
 237                chunk_lookup += GRAPH_CHUNKLOOKUP_WIDTH;
 238
 239                if (chunk_offset > graph_size - the_hash_algo->rawsz) {
 240                        error(_("commit-graph improper chunk offset %08x%08x"), (uint32_t)(chunk_offset >> 32),
 241                              (uint32_t)chunk_offset);
 242                        free(graph);
 243                        return NULL;
 244                }
 245
 246                switch (chunk_id) {
 247                case GRAPH_CHUNKID_OIDFANOUT:
 248                        if (graph->chunk_oid_fanout)
 249                                chunk_repeated = 1;
 250                        else
 251                                graph->chunk_oid_fanout = (uint32_t*)(data + chunk_offset);
 252                        break;
 253
 254                case GRAPH_CHUNKID_OIDLOOKUP:
 255                        if (graph->chunk_oid_lookup)
 256                                chunk_repeated = 1;
 257                        else
 258                                graph->chunk_oid_lookup = data + chunk_offset;
 259                        break;
 260
 261                case GRAPH_CHUNKID_DATA:
 262                        if (graph->chunk_commit_data)
 263                                chunk_repeated = 1;
 264                        else
 265                                graph->chunk_commit_data = data + chunk_offset;
 266                        break;
 267
 268                case GRAPH_CHUNKID_EXTRAEDGES:
 269                        if (graph->chunk_extra_edges)
 270                                chunk_repeated = 1;
 271                        else
 272                                graph->chunk_extra_edges = data + chunk_offset;
 273                        break;
 274
 275                case GRAPH_CHUNKID_BASE:
 276                        if (graph->chunk_base_graphs)
 277                                chunk_repeated = 1;
 278                        else
 279                                graph->chunk_base_graphs = data + chunk_offset;
 280                }
 281
 282                if (chunk_repeated) {
 283                        error(_("commit-graph chunk id %08x appears multiple times"), chunk_id);
 284                        free(graph);
 285                        return NULL;
 286                }
 287
 288                if (last_chunk_id == GRAPH_CHUNKID_OIDLOOKUP)
 289                {
 290                        graph->num_commits = (chunk_offset - last_chunk_offset)
 291                                             / graph->hash_len;
 292                }
 293
 294                last_chunk_id = chunk_id;
 295                last_chunk_offset = chunk_offset;
 296        }
 297
 298        hashcpy(graph->oid.hash, graph->data + graph->data_len - graph->hash_len);
 299
 300        if (verify_commit_graph_lite(graph))
 301                return NULL;
 302
 303        return graph;
 304}
 305
 306static struct commit_graph *load_commit_graph_one(const char *graph_file)
 307{
 308
 309        struct stat st;
 310        int fd;
 311        struct commit_graph *g;
 312        int open_ok = open_commit_graph(graph_file, &fd, &st);
 313
 314        if (!open_ok)
 315                return NULL;
 316
 317        g = load_commit_graph_one_fd_st(fd, &st);
 318
 319        if (g)
 320                g->filename = xstrdup(graph_file);
 321
 322        return g;
 323}
 324
 325static struct commit_graph *load_commit_graph_v1(struct repository *r, const char *obj_dir)
 326{
 327        char *graph_name = get_commit_graph_filename(obj_dir);
 328        struct commit_graph *g = load_commit_graph_one(graph_name);
 329        free(graph_name);
 330
 331        if (g)
 332                g->obj_dir = obj_dir;
 333
 334        return g;
 335}
 336
 337static int add_graph_to_chain(struct commit_graph *g,
 338                              struct commit_graph *chain,
 339                              struct object_id *oids,
 340                              int n)
 341{
 342        struct commit_graph *cur_g = chain;
 343
 344        if (n && !g->chunk_base_graphs) {
 345                warning(_("commit-graph has no base graphs chunk"));
 346                return 0;
 347        }
 348
 349        while (n) {
 350                n--;
 351
 352                if (!cur_g ||
 353                    !oideq(&oids[n], &cur_g->oid) ||
 354                    !hasheq(oids[n].hash, g->chunk_base_graphs + g->hash_len * n)) {
 355                        warning(_("commit-graph chain does not match"));
 356                        return 0;
 357                }
 358
 359                cur_g = cur_g->base_graph;
 360        }
 361
 362        g->base_graph = chain;
 363
 364        if (chain)
 365                g->num_commits_in_base = chain->num_commits + chain->num_commits_in_base;
 366
 367        return 1;
 368}
 369
 370static struct commit_graph *load_commit_graph_chain(struct repository *r, const char *obj_dir)
 371{
 372        struct commit_graph *graph_chain = NULL;
 373        struct strbuf line = STRBUF_INIT;
 374        struct stat st;
 375        struct object_id *oids;
 376        int i = 0, valid = 1, count;
 377        char *chain_name = get_chain_filename(obj_dir);
 378        FILE *fp;
 379        int stat_res;
 380
 381        fp = fopen(chain_name, "r");
 382        stat_res = stat(chain_name, &st);
 383        free(chain_name);
 384
 385        if (!fp ||
 386            stat_res ||
 387            st.st_size <= the_hash_algo->hexsz)
 388                return NULL;
 389
 390        count = st.st_size / (the_hash_algo->hexsz + 1);
 391        oids = xcalloc(count, sizeof(struct object_id));
 392
 393        prepare_alt_odb(r);
 394
 395        for (i = 0; i < count; i++) {
 396                struct object_directory *odb;
 397
 398                if (strbuf_getline_lf(&line, fp) == EOF)
 399                        break;
 400
 401                if (get_oid_hex(line.buf, &oids[i])) {
 402                        warning(_("invalid commit-graph chain: line '%s' not a hash"),
 403                                line.buf);
 404                        valid = 0;
 405                        break;
 406                }
 407
 408                valid = 0;
 409                for (odb = r->objects->odb; odb; odb = odb->next) {
 410                        char *graph_name = get_split_graph_filename(odb->path, line.buf);
 411                        struct commit_graph *g = load_commit_graph_one(graph_name);
 412
 413                        free(graph_name);
 414
 415                        if (g) {
 416                                g->obj_dir = odb->path;
 417
 418                                if (add_graph_to_chain(g, graph_chain, oids, i)) {
 419                                        graph_chain = g;
 420                                        valid = 1;
 421                                }
 422
 423                                break;
 424                        }
 425                }
 426
 427                if (!valid) {
 428                        warning(_("unable to find all commit-graph files"));
 429                        break;
 430                }
 431        }
 432
 433        free(oids);
 434        fclose(fp);
 435
 436        return graph_chain;
 437}
 438
 439struct commit_graph *read_commit_graph_one(struct repository *r, const char *obj_dir)
 440{
 441        struct commit_graph *g = load_commit_graph_v1(r, obj_dir);
 442
 443        if (!g)
 444                g = load_commit_graph_chain(r, obj_dir);
 445
 446        return g;
 447}
 448
 449static void prepare_commit_graph_one(struct repository *r, const char *obj_dir)
 450{
 451
 452        if (r->objects->commit_graph)
 453                return;
 454
 455        r->objects->commit_graph = read_commit_graph_one(r, obj_dir);
 456}
 457
 458/*
 459 * Return 1 if commit_graph is non-NULL, and 0 otherwise.
 460 *
 461 * On the first invocation, this function attemps to load the commit
 462 * graph if the_repository is configured to have one.
 463 */
 464static int prepare_commit_graph(struct repository *r)
 465{
 466        struct object_directory *odb;
 467        int config_value;
 468
 469        if (git_env_bool(GIT_TEST_COMMIT_GRAPH_DIE_ON_LOAD, 0))
 470                die("dying as requested by the '%s' variable on commit-graph load!",
 471                    GIT_TEST_COMMIT_GRAPH_DIE_ON_LOAD);
 472
 473        if (r->objects->commit_graph_attempted)
 474                return !!r->objects->commit_graph;
 475        r->objects->commit_graph_attempted = 1;
 476
 477        if (!git_env_bool(GIT_TEST_COMMIT_GRAPH, 0) &&
 478            (repo_config_get_bool(r, "core.commitgraph", &config_value) ||
 479            !config_value))
 480                /*
 481                 * This repository is not configured to use commit graphs, so
 482                 * do not load one. (But report commit_graph_attempted anyway
 483                 * so that commit graph loading is not attempted again for this
 484                 * repository.)
 485                 */
 486                return 0;
 487
 488        if (!commit_graph_compatible(r))
 489                return 0;
 490
 491        prepare_alt_odb(r);
 492        for (odb = r->objects->odb;
 493             !r->objects->commit_graph && odb;
 494             odb = odb->next)
 495                prepare_commit_graph_one(r, odb->path);
 496        return !!r->objects->commit_graph;
 497}
 498
 499int generation_numbers_enabled(struct repository *r)
 500{
 501        uint32_t first_generation;
 502        struct commit_graph *g;
 503        if (!prepare_commit_graph(r))
 504               return 0;
 505
 506        g = r->objects->commit_graph;
 507
 508        if (!g->num_commits)
 509                return 0;
 510
 511        first_generation = get_be32(g->chunk_commit_data +
 512                                    g->hash_len + 8) >> 2;
 513
 514        return !!first_generation;
 515}
 516
 517static void close_commit_graph_one(struct commit_graph *g)
 518{
 519        if (!g)
 520                return;
 521
 522        close_commit_graph_one(g->base_graph);
 523        free_commit_graph(g);
 524}
 525
 526void close_commit_graph(struct raw_object_store *o)
 527{
 528        close_commit_graph_one(o->commit_graph);
 529        o->commit_graph = NULL;
 530}
 531
 532static int bsearch_graph(struct commit_graph *g, struct object_id *oid, uint32_t *pos)
 533{
 534        return bsearch_hash(oid->hash, g->chunk_oid_fanout,
 535                            g->chunk_oid_lookup, g->hash_len, pos);
 536}
 537
 538static void load_oid_from_graph(struct commit_graph *g,
 539                                uint32_t pos,
 540                                struct object_id *oid)
 541{
 542        uint32_t lex_index;
 543
 544        while (g && pos < g->num_commits_in_base)
 545                g = g->base_graph;
 546
 547        if (!g)
 548                BUG("NULL commit-graph");
 549
 550        if (pos >= g->num_commits + g->num_commits_in_base)
 551                die(_("invalid commit position. commit-graph is likely corrupt"));
 552
 553        lex_index = pos - g->num_commits_in_base;
 554
 555        hashcpy(oid->hash, g->chunk_oid_lookup + g->hash_len * lex_index);
 556}
 557
 558static struct commit_list **insert_parent_or_die(struct repository *r,
 559                                                 struct commit_graph *g,
 560                                                 uint32_t pos,
 561                                                 struct commit_list **pptr)
 562{
 563        struct commit *c;
 564        struct object_id oid;
 565
 566        if (pos >= g->num_commits + g->num_commits_in_base)
 567                die("invalid parent position %"PRIu32, pos);
 568
 569        load_oid_from_graph(g, pos, &oid);
 570        c = lookup_commit(r, &oid);
 571        if (!c)
 572                die(_("could not find commit %s"), oid_to_hex(&oid));
 573        c->graph_pos = pos;
 574        return &commit_list_insert(c, pptr)->next;
 575}
 576
 577static void fill_commit_graph_info(struct commit *item, struct commit_graph *g, uint32_t pos)
 578{
 579        const unsigned char *commit_data;
 580        uint32_t lex_index;
 581
 582        while (pos < g->num_commits_in_base)
 583                g = g->base_graph;
 584
 585        lex_index = pos - g->num_commits_in_base;
 586        commit_data = g->chunk_commit_data + GRAPH_DATA_WIDTH * lex_index;
 587        item->graph_pos = pos;
 588        item->generation = get_be32(commit_data + g->hash_len + 8) >> 2;
 589}
 590
 591static int fill_commit_in_graph(struct repository *r,
 592                                struct commit *item,
 593                                struct commit_graph *g, uint32_t pos)
 594{
 595        uint32_t edge_value;
 596        uint32_t *parent_data_ptr;
 597        uint64_t date_low, date_high;
 598        struct commit_list **pptr;
 599        const unsigned char *commit_data;
 600        uint32_t lex_index;
 601
 602        while (pos < g->num_commits_in_base)
 603                g = g->base_graph;
 604
 605        if (pos >= g->num_commits + g->num_commits_in_base)
 606                die(_("invalid commit position. commit-graph is likely corrupt"));
 607
 608        /*
 609         * Store the "full" position, but then use the
 610         * "local" position for the rest of the calculation.
 611         */
 612        item->graph_pos = pos;
 613        lex_index = pos - g->num_commits_in_base;
 614
 615        commit_data = g->chunk_commit_data + (g->hash_len + 16) * lex_index;
 616
 617        item->object.parsed = 1;
 618
 619        item->maybe_tree = NULL;
 620
 621        date_high = get_be32(commit_data + g->hash_len + 8) & 0x3;
 622        date_low = get_be32(commit_data + g->hash_len + 12);
 623        item->date = (timestamp_t)((date_high << 32) | date_low);
 624
 625        item->generation = get_be32(commit_data + g->hash_len + 8) >> 2;
 626
 627        pptr = &item->parents;
 628
 629        edge_value = get_be32(commit_data + g->hash_len);
 630        if (edge_value == GRAPH_PARENT_NONE)
 631                return 1;
 632        pptr = insert_parent_or_die(r, g, edge_value, pptr);
 633
 634        edge_value = get_be32(commit_data + g->hash_len + 4);
 635        if (edge_value == GRAPH_PARENT_NONE)
 636                return 1;
 637        if (!(edge_value & GRAPH_EXTRA_EDGES_NEEDED)) {
 638                pptr = insert_parent_or_die(r, g, edge_value, pptr);
 639                return 1;
 640        }
 641
 642        parent_data_ptr = (uint32_t*)(g->chunk_extra_edges +
 643                          4 * (uint64_t)(edge_value & GRAPH_EDGE_LAST_MASK));
 644        do {
 645                edge_value = get_be32(parent_data_ptr);
 646                pptr = insert_parent_or_die(r, g,
 647                                            edge_value & GRAPH_EDGE_LAST_MASK,
 648                                            pptr);
 649                parent_data_ptr++;
 650        } while (!(edge_value & GRAPH_LAST_EDGE));
 651
 652        return 1;
 653}
 654
 655static int find_commit_in_graph(struct commit *item, struct commit_graph *g, uint32_t *pos)
 656{
 657        if (item->graph_pos != COMMIT_NOT_FROM_GRAPH) {
 658                *pos = item->graph_pos;
 659                return 1;
 660        } else {
 661                struct commit_graph *cur_g = g;
 662                uint32_t lex_index;
 663
 664                while (cur_g && !bsearch_graph(cur_g, &(item->object.oid), &lex_index))
 665                        cur_g = cur_g->base_graph;
 666
 667                if (cur_g) {
 668                        *pos = lex_index + cur_g->num_commits_in_base;
 669                        return 1;
 670                }
 671
 672                return 0;
 673        }
 674}
 675
 676static int parse_commit_in_graph_one(struct repository *r,
 677                                     struct commit_graph *g,
 678                                     struct commit *item)
 679{
 680        uint32_t pos;
 681
 682        if (item->object.parsed)
 683                return 1;
 684
 685        if (find_commit_in_graph(item, g, &pos))
 686                return fill_commit_in_graph(r, item, g, pos);
 687
 688        return 0;
 689}
 690
 691int parse_commit_in_graph(struct repository *r, struct commit *item)
 692{
 693        if (!prepare_commit_graph(r))
 694                return 0;
 695        return parse_commit_in_graph_one(r, r->objects->commit_graph, item);
 696}
 697
 698void load_commit_graph_info(struct repository *r, struct commit *item)
 699{
 700        uint32_t pos;
 701        if (!prepare_commit_graph(r))
 702                return;
 703        if (find_commit_in_graph(item, r->objects->commit_graph, &pos))
 704                fill_commit_graph_info(item, r->objects->commit_graph, pos);
 705}
 706
 707static struct tree *load_tree_for_commit(struct repository *r,
 708                                         struct commit_graph *g,
 709                                         struct commit *c)
 710{
 711        struct object_id oid;
 712        const unsigned char *commit_data;
 713
 714        while (c->graph_pos < g->num_commits_in_base)
 715                g = g->base_graph;
 716
 717        commit_data = g->chunk_commit_data +
 718                        GRAPH_DATA_WIDTH * (c->graph_pos - g->num_commits_in_base);
 719
 720        hashcpy(oid.hash, commit_data);
 721        c->maybe_tree = lookup_tree(r, &oid);
 722
 723        return c->maybe_tree;
 724}
 725
 726static struct tree *get_commit_tree_in_graph_one(struct repository *r,
 727                                                 struct commit_graph *g,
 728                                                 const struct commit *c)
 729{
 730        if (c->maybe_tree)
 731                return c->maybe_tree;
 732        if (c->graph_pos == COMMIT_NOT_FROM_GRAPH)
 733                BUG("get_commit_tree_in_graph_one called from non-commit-graph commit");
 734
 735        return load_tree_for_commit(r, g, (struct commit *)c);
 736}
 737
 738struct tree *get_commit_tree_in_graph(struct repository *r, const struct commit *c)
 739{
 740        return get_commit_tree_in_graph_one(r, r->objects->commit_graph, c);
 741}
 742
 743struct packed_commit_list {
 744        struct commit **list;
 745        int nr;
 746        int alloc;
 747};
 748
 749struct packed_oid_list {
 750        struct object_id *list;
 751        int nr;
 752        int alloc;
 753};
 754
 755struct write_commit_graph_context {
 756        struct repository *r;
 757        char *obj_dir;
 758        char *graph_name;
 759        struct packed_oid_list oids;
 760        struct packed_commit_list commits;
 761        int num_extra_edges;
 762        unsigned long approx_nr_objects;
 763        struct progress *progress;
 764        int progress_done;
 765        uint64_t progress_cnt;
 766
 767        char *base_graph_name;
 768        int num_commit_graphs_before;
 769        int num_commit_graphs_after;
 770        char **commit_graph_filenames_before;
 771        char **commit_graph_filenames_after;
 772        char **commit_graph_hash_after;
 773        uint32_t new_num_commits_in_base;
 774        struct commit_graph *new_base_graph;
 775
 776        unsigned append:1,
 777                 report_progress:1,
 778                 split:1;
 779
 780        const struct split_commit_graph_opts *split_opts;
 781};
 782
 783static void write_graph_chunk_fanout(struct hashfile *f,
 784                                     struct write_commit_graph_context *ctx)
 785{
 786        int i, count = 0;
 787        struct commit **list = ctx->commits.list;
 788
 789        /*
 790         * Write the first-level table (the list is sorted,
 791         * but we use a 256-entry lookup to be able to avoid
 792         * having to do eight extra binary search iterations).
 793         */
 794        for (i = 0; i < 256; i++) {
 795                while (count < ctx->commits.nr) {
 796                        if ((*list)->object.oid.hash[0] != i)
 797                                break;
 798                        display_progress(ctx->progress, ++ctx->progress_cnt);
 799                        count++;
 800                        list++;
 801                }
 802
 803                hashwrite_be32(f, count);
 804        }
 805}
 806
 807static void write_graph_chunk_oids(struct hashfile *f, int hash_len,
 808                                   struct write_commit_graph_context *ctx)
 809{
 810        struct commit **list = ctx->commits.list;
 811        int count;
 812        for (count = 0; count < ctx->commits.nr; count++, list++) {
 813                display_progress(ctx->progress, ++ctx->progress_cnt);
 814                hashwrite(f, (*list)->object.oid.hash, (int)hash_len);
 815        }
 816}
 817
 818static const unsigned char *commit_to_sha1(size_t index, void *table)
 819{
 820        struct commit **commits = table;
 821        return commits[index]->object.oid.hash;
 822}
 823
 824static void write_graph_chunk_data(struct hashfile *f, int hash_len,
 825                                   struct write_commit_graph_context *ctx)
 826{
 827        struct commit **list = ctx->commits.list;
 828        struct commit **last = ctx->commits.list + ctx->commits.nr;
 829        uint32_t num_extra_edges = 0;
 830
 831        while (list < last) {
 832                struct commit_list *parent;
 833                int edge_value;
 834                uint32_t packedDate[2];
 835                display_progress(ctx->progress, ++ctx->progress_cnt);
 836
 837                parse_commit_no_graph(*list);
 838                hashwrite(f, get_commit_tree_oid(*list)->hash, hash_len);
 839
 840                parent = (*list)->parents;
 841
 842                if (!parent)
 843                        edge_value = GRAPH_PARENT_NONE;
 844                else {
 845                        edge_value = sha1_pos(parent->item->object.oid.hash,
 846                                              ctx->commits.list,
 847                                              ctx->commits.nr,
 848                                              commit_to_sha1);
 849
 850                        if (edge_value >= 0)
 851                                edge_value += ctx->new_num_commits_in_base;
 852                        else {
 853                                uint32_t pos;
 854                                if (find_commit_in_graph(parent->item,
 855                                                         ctx->new_base_graph,
 856                                                         &pos))
 857                                        edge_value = pos;
 858                        }
 859
 860                        if (edge_value < 0)
 861                                BUG("missing parent %s for commit %s",
 862                                    oid_to_hex(&parent->item->object.oid),
 863                                    oid_to_hex(&(*list)->object.oid));
 864                }
 865
 866                hashwrite_be32(f, edge_value);
 867
 868                if (parent)
 869                        parent = parent->next;
 870
 871                if (!parent)
 872                        edge_value = GRAPH_PARENT_NONE;
 873                else if (parent->next)
 874                        edge_value = GRAPH_EXTRA_EDGES_NEEDED | num_extra_edges;
 875                else {
 876                        edge_value = sha1_pos(parent->item->object.oid.hash,
 877                                              ctx->commits.list,
 878                                              ctx->commits.nr,
 879                                              commit_to_sha1);
 880
 881                        if (edge_value >= 0)
 882                                edge_value += ctx->new_num_commits_in_base;
 883                        else {
 884                                uint32_t pos;
 885                                if (find_commit_in_graph(parent->item,
 886                                                         ctx->new_base_graph,
 887                                                         &pos))
 888                                        edge_value = pos;
 889                        }
 890
 891                        if (edge_value < 0)
 892                                BUG("missing parent %s for commit %s",
 893                                    oid_to_hex(&parent->item->object.oid),
 894                                    oid_to_hex(&(*list)->object.oid));
 895                }
 896
 897                hashwrite_be32(f, edge_value);
 898
 899                if (edge_value & GRAPH_EXTRA_EDGES_NEEDED) {
 900                        do {
 901                                num_extra_edges++;
 902                                parent = parent->next;
 903                        } while (parent);
 904                }
 905
 906                if (sizeof((*list)->date) > 4)
 907                        packedDate[0] = htonl(((*list)->date >> 32) & 0x3);
 908                else
 909                        packedDate[0] = 0;
 910
 911                packedDate[0] |= htonl((*list)->generation << 2);
 912
 913                packedDate[1] = htonl((*list)->date);
 914                hashwrite(f, packedDate, 8);
 915
 916                list++;
 917        }
 918}
 919
 920static void write_graph_chunk_extra_edges(struct hashfile *f,
 921                                          struct write_commit_graph_context *ctx)
 922{
 923        struct commit **list = ctx->commits.list;
 924        struct commit **last = ctx->commits.list + ctx->commits.nr;
 925        struct commit_list *parent;
 926
 927        while (list < last) {
 928                int num_parents = 0;
 929
 930                display_progress(ctx->progress, ++ctx->progress_cnt);
 931
 932                for (parent = (*list)->parents; num_parents < 3 && parent;
 933                     parent = parent->next)
 934                        num_parents++;
 935
 936                if (num_parents <= 2) {
 937                        list++;
 938                        continue;
 939                }
 940
 941                /* Since num_parents > 2, this initializer is safe. */
 942                for (parent = (*list)->parents->next; parent; parent = parent->next) {
 943                        int edge_value = sha1_pos(parent->item->object.oid.hash,
 944                                                  ctx->commits.list,
 945                                                  ctx->commits.nr,
 946                                                  commit_to_sha1);
 947
 948                        if (edge_value >= 0)
 949                                edge_value += ctx->new_num_commits_in_base;
 950                        else {
 951                                uint32_t pos;
 952                                if (find_commit_in_graph(parent->item,
 953                                                         ctx->new_base_graph,
 954                                                         &pos))
 955                                        edge_value = pos;
 956                        }
 957
 958                        if (edge_value < 0)
 959                                BUG("missing parent %s for commit %s",
 960                                    oid_to_hex(&parent->item->object.oid),
 961                                    oid_to_hex(&(*list)->object.oid));
 962                        else if (!parent->next)
 963                                edge_value |= GRAPH_LAST_EDGE;
 964
 965                        hashwrite_be32(f, edge_value);
 966                }
 967
 968                list++;
 969        }
 970}
 971
 972static int oid_compare(const void *_a, const void *_b)
 973{
 974        const struct object_id *a = (const struct object_id *)_a;
 975        const struct object_id *b = (const struct object_id *)_b;
 976        return oidcmp(a, b);
 977}
 978
 979static int add_packed_commits(const struct object_id *oid,
 980                              struct packed_git *pack,
 981                              uint32_t pos,
 982                              void *data)
 983{
 984        struct write_commit_graph_context *ctx = (struct write_commit_graph_context*)data;
 985        enum object_type type;
 986        off_t offset = nth_packed_object_offset(pack, pos);
 987        struct object_info oi = OBJECT_INFO_INIT;
 988
 989        if (ctx->progress)
 990                display_progress(ctx->progress, ++ctx->progress_done);
 991
 992        oi.typep = &type;
 993        if (packed_object_info(ctx->r, pack, offset, &oi) < 0)
 994                die(_("unable to get type of object %s"), oid_to_hex(oid));
 995
 996        if (type != OBJ_COMMIT)
 997                return 0;
 998
 999        ALLOC_GROW(ctx->oids.list, ctx->oids.nr + 1, ctx->oids.alloc);
1000        oidcpy(&(ctx->oids.list[ctx->oids.nr]), oid);
1001        ctx->oids.nr++;
1002
1003        return 0;
1004}
1005
1006static void add_missing_parents(struct write_commit_graph_context *ctx, struct commit *commit)
1007{
1008        struct commit_list *parent;
1009        for (parent = commit->parents; parent; parent = parent->next) {
1010                if (!(parent->item->object.flags & UNINTERESTING)) {
1011                        ALLOC_GROW(ctx->oids.list, ctx->oids.nr + 1, ctx->oids.alloc);
1012                        oidcpy(&ctx->oids.list[ctx->oids.nr], &(parent->item->object.oid));
1013                        ctx->oids.nr++;
1014                        parent->item->object.flags |= UNINTERESTING;
1015                }
1016        }
1017}
1018
1019static void close_reachable(struct write_commit_graph_context *ctx)
1020{
1021        int i;
1022        struct commit *commit;
1023
1024        if (ctx->report_progress)
1025                ctx->progress = start_delayed_progress(
1026                                        _("Loading known commits in commit graph"),
1027                                        ctx->oids.nr);
1028        for (i = 0; i < ctx->oids.nr; i++) {
1029                display_progress(ctx->progress, i + 1);
1030                commit = lookup_commit(ctx->r, &ctx->oids.list[i]);
1031                if (commit)
1032                        commit->object.flags |= UNINTERESTING;
1033        }
1034        stop_progress(&ctx->progress);
1035
1036        /*
1037         * As this loop runs, ctx->oids.nr may grow, but not more
1038         * than the number of missing commits in the reachable
1039         * closure.
1040         */
1041        if (ctx->report_progress)
1042                ctx->progress = start_delayed_progress(
1043                                        _("Expanding reachable commits in commit graph"),
1044                                        ctx->oids.nr);
1045        for (i = 0; i < ctx->oids.nr; i++) {
1046                display_progress(ctx->progress, i + 1);
1047                commit = lookup_commit(ctx->r, &ctx->oids.list[i]);
1048
1049                if (!commit)
1050                        continue;
1051                if (ctx->split) {
1052                        if (!parse_commit(commit) &&
1053                            commit->graph_pos == COMMIT_NOT_FROM_GRAPH)
1054                                add_missing_parents(ctx, commit);
1055                } else if (!parse_commit_no_graph(commit))
1056                        add_missing_parents(ctx, commit);
1057        }
1058        stop_progress(&ctx->progress);
1059
1060        if (ctx->report_progress)
1061                ctx->progress = start_delayed_progress(
1062                                        _("Clearing commit marks in commit graph"),
1063                                        ctx->oids.nr);
1064        for (i = 0; i < ctx->oids.nr; i++) {
1065                display_progress(ctx->progress, i + 1);
1066                commit = lookup_commit(ctx->r, &ctx->oids.list[i]);
1067
1068                if (commit)
1069                        commit->object.flags &= ~UNINTERESTING;
1070        }
1071        stop_progress(&ctx->progress);
1072}
1073
1074static void compute_generation_numbers(struct write_commit_graph_context *ctx)
1075{
1076        int i;
1077        struct commit_list *list = NULL;
1078
1079        if (ctx->report_progress)
1080                ctx->progress = start_progress(
1081                                        _("Computing commit graph generation numbers"),
1082                                        ctx->commits.nr);
1083        for (i = 0; i < ctx->commits.nr; i++) {
1084                display_progress(ctx->progress, i + 1);
1085                if (ctx->commits.list[i]->generation != GENERATION_NUMBER_INFINITY &&
1086                    ctx->commits.list[i]->generation != GENERATION_NUMBER_ZERO)
1087                        continue;
1088
1089                commit_list_insert(ctx->commits.list[i], &list);
1090                while (list) {
1091                        struct commit *current = list->item;
1092                        struct commit_list *parent;
1093                        int all_parents_computed = 1;
1094                        uint32_t max_generation = 0;
1095
1096                        for (parent = current->parents; parent; parent = parent->next) {
1097                                if (parent->item->generation == GENERATION_NUMBER_INFINITY ||
1098                                    parent->item->generation == GENERATION_NUMBER_ZERO) {
1099                                        all_parents_computed = 0;
1100                                        commit_list_insert(parent->item, &list);
1101                                        break;
1102                                } else if (parent->item->generation > max_generation) {
1103                                        max_generation = parent->item->generation;
1104                                }
1105                        }
1106
1107                        if (all_parents_computed) {
1108                                current->generation = max_generation + 1;
1109                                pop_commit(&list);
1110
1111                                if (current->generation > GENERATION_NUMBER_MAX)
1112                                        current->generation = GENERATION_NUMBER_MAX;
1113                        }
1114                }
1115        }
1116        stop_progress(&ctx->progress);
1117}
1118
1119static int add_ref_to_list(const char *refname,
1120                           const struct object_id *oid,
1121                           int flags, void *cb_data)
1122{
1123        struct string_list *list = (struct string_list *)cb_data;
1124
1125        string_list_append(list, oid_to_hex(oid));
1126        return 0;
1127}
1128
1129int write_commit_graph_reachable(const char *obj_dir, unsigned int flags,
1130                                 const struct split_commit_graph_opts *split_opts)
1131{
1132        struct string_list list = STRING_LIST_INIT_DUP;
1133        int result;
1134
1135        for_each_ref(add_ref_to_list, &list);
1136        result = write_commit_graph(obj_dir, NULL, &list,
1137                                    flags, split_opts);
1138
1139        string_list_clear(&list, 0);
1140        return result;
1141}
1142
1143static int fill_oids_from_packs(struct write_commit_graph_context *ctx,
1144                                struct string_list *pack_indexes)
1145{
1146        uint32_t i;
1147        struct strbuf progress_title = STRBUF_INIT;
1148        struct strbuf packname = STRBUF_INIT;
1149        int dirlen;
1150
1151        strbuf_addf(&packname, "%s/pack/", ctx->obj_dir);
1152        dirlen = packname.len;
1153        if (ctx->report_progress) {
1154                strbuf_addf(&progress_title,
1155                            Q_("Finding commits for commit graph in %d pack",
1156                               "Finding commits for commit graph in %d packs",
1157                               pack_indexes->nr),
1158                            pack_indexes->nr);
1159                ctx->progress = start_delayed_progress(progress_title.buf, 0);
1160                ctx->progress_done = 0;
1161        }
1162        for (i = 0; i < pack_indexes->nr; i++) {
1163                struct packed_git *p;
1164                strbuf_setlen(&packname, dirlen);
1165                strbuf_addstr(&packname, pack_indexes->items[i].string);
1166                p = add_packed_git(packname.buf, packname.len, 1);
1167                if (!p) {
1168                        error(_("error adding pack %s"), packname.buf);
1169                        return -1;
1170                }
1171                if (open_pack_index(p)) {
1172                        error(_("error opening index for %s"), packname.buf);
1173                        return -1;
1174                }
1175                for_each_object_in_pack(p, add_packed_commits, ctx,
1176                                        FOR_EACH_OBJECT_PACK_ORDER);
1177                close_pack(p);
1178                free(p);
1179        }
1180
1181        stop_progress(&ctx->progress);
1182        strbuf_reset(&progress_title);
1183        strbuf_release(&packname);
1184
1185        return 0;
1186}
1187
1188static void fill_oids_from_commit_hex(struct write_commit_graph_context *ctx,
1189                                      struct string_list *commit_hex)
1190{
1191        uint32_t i;
1192        struct strbuf progress_title = STRBUF_INIT;
1193
1194        if (ctx->report_progress) {
1195                strbuf_addf(&progress_title,
1196                            Q_("Finding commits for commit graph from %d ref",
1197                               "Finding commits for commit graph from %d refs",
1198                               commit_hex->nr),
1199                            commit_hex->nr);
1200                ctx->progress = start_delayed_progress(
1201                                        progress_title.buf,
1202                                        commit_hex->nr);
1203        }
1204        for (i = 0; i < commit_hex->nr; i++) {
1205                const char *end;
1206                struct object_id oid;
1207                struct commit *result;
1208
1209                display_progress(ctx->progress, i + 1);
1210                if (commit_hex->items[i].string &&
1211                    parse_oid_hex(commit_hex->items[i].string, &oid, &end))
1212                        continue;
1213
1214                result = lookup_commit_reference_gently(ctx->r, &oid, 1);
1215
1216                if (result) {
1217                        ALLOC_GROW(ctx->oids.list, ctx->oids.nr + 1, ctx->oids.alloc);
1218                        oidcpy(&ctx->oids.list[ctx->oids.nr], &(result->object.oid));
1219                        ctx->oids.nr++;
1220                }
1221        }
1222        stop_progress(&ctx->progress);
1223        strbuf_release(&progress_title);
1224}
1225
1226static void fill_oids_from_all_packs(struct write_commit_graph_context *ctx)
1227{
1228        if (ctx->report_progress)
1229                ctx->progress = start_delayed_progress(
1230                        _("Finding commits for commit graph among packed objects"),
1231                        ctx->approx_nr_objects);
1232        for_each_packed_object(add_packed_commits, ctx,
1233                               FOR_EACH_OBJECT_PACK_ORDER);
1234        if (ctx->progress_done < ctx->approx_nr_objects)
1235                display_progress(ctx->progress, ctx->approx_nr_objects);
1236        stop_progress(&ctx->progress);
1237}
1238
1239static uint32_t count_distinct_commits(struct write_commit_graph_context *ctx)
1240{
1241        uint32_t i, count_distinct = 1;
1242
1243        if (ctx->report_progress)
1244                ctx->progress = start_delayed_progress(
1245                        _("Counting distinct commits in commit graph"),
1246                        ctx->oids.nr);
1247        display_progress(ctx->progress, 0); /* TODO: Measure QSORT() progress */
1248        QSORT(ctx->oids.list, ctx->oids.nr, oid_compare);
1249
1250        for (i = 1; i < ctx->oids.nr; i++) {
1251                display_progress(ctx->progress, i + 1);
1252                if (!oideq(&ctx->oids.list[i - 1], &ctx->oids.list[i])) {
1253                        if (ctx->split) {
1254                                struct commit *c = lookup_commit(ctx->r, &ctx->oids.list[i]);
1255
1256                                if (!c || c->graph_pos != COMMIT_NOT_FROM_GRAPH)
1257                                        continue;
1258                        }
1259
1260                        count_distinct++;
1261                }
1262        }
1263        stop_progress(&ctx->progress);
1264
1265        return count_distinct;
1266}
1267
1268static void copy_oids_to_commits(struct write_commit_graph_context *ctx)
1269{
1270        uint32_t i;
1271        struct commit_list *parent;
1272
1273        ctx->num_extra_edges = 0;
1274        if (ctx->report_progress)
1275                ctx->progress = start_delayed_progress(
1276                        _("Finding extra edges in commit graph"),
1277                        ctx->oids.nr);
1278        for (i = 0; i < ctx->oids.nr; i++) {
1279                int num_parents = 0;
1280                display_progress(ctx->progress, i + 1);
1281                if (i > 0 && oideq(&ctx->oids.list[i - 1], &ctx->oids.list[i]))
1282                        continue;
1283
1284                ALLOC_GROW(ctx->commits.list, ctx->commits.nr + 1, ctx->commits.alloc);
1285                ctx->commits.list[ctx->commits.nr] = lookup_commit(ctx->r, &ctx->oids.list[i]);
1286
1287                if (ctx->split &&
1288                    ctx->commits.list[ctx->commits.nr]->graph_pos != COMMIT_NOT_FROM_GRAPH)
1289                        continue;
1290
1291                parse_commit_no_graph(ctx->commits.list[ctx->commits.nr]);
1292
1293                for (parent = ctx->commits.list[ctx->commits.nr]->parents;
1294                     parent; parent = parent->next)
1295                        num_parents++;
1296
1297                if (num_parents > 2)
1298                        ctx->num_extra_edges += num_parents - 1;
1299
1300                ctx->commits.nr++;
1301        }
1302        stop_progress(&ctx->progress);
1303}
1304
1305static int write_graph_chunk_base_1(struct hashfile *f,
1306                                    struct commit_graph *g)
1307{
1308        int num = 0;
1309
1310        if (!g)
1311                return 0;
1312
1313        num = write_graph_chunk_base_1(f, g->base_graph);
1314        hashwrite(f, g->oid.hash, the_hash_algo->rawsz);
1315        return num + 1;
1316}
1317
1318static int write_graph_chunk_base(struct hashfile *f,
1319                                  struct write_commit_graph_context *ctx)
1320{
1321        int num = write_graph_chunk_base_1(f, ctx->new_base_graph);
1322
1323        if (num != ctx->num_commit_graphs_after - 1) {
1324                error(_("failed to write correct number of base graph ids"));
1325                return -1;
1326        }
1327
1328        return 0;
1329}
1330
1331static int write_commit_graph_file(struct write_commit_graph_context *ctx)
1332{
1333        uint32_t i;
1334        int fd;
1335        struct hashfile *f;
1336        struct lock_file lk = LOCK_INIT;
1337        uint32_t chunk_ids[6];
1338        uint64_t chunk_offsets[6];
1339        const unsigned hashsz = the_hash_algo->rawsz;
1340        struct strbuf progress_title = STRBUF_INIT;
1341        int num_chunks = 3;
1342        struct object_id file_hash;
1343
1344        if (ctx->split) {
1345                struct strbuf tmp_file = STRBUF_INIT;
1346
1347                strbuf_addf(&tmp_file,
1348                            "%s/info/commit-graphs/tmp_graph_XXXXXX",
1349                            ctx->obj_dir);
1350                ctx->graph_name = strbuf_detach(&tmp_file, NULL);
1351        } else {
1352                ctx->graph_name = get_commit_graph_filename(ctx->obj_dir);
1353        }
1354
1355        if (safe_create_leading_directories(ctx->graph_name)) {
1356                UNLEAK(ctx->graph_name);
1357                error(_("unable to create leading directories of %s"),
1358                        ctx->graph_name);
1359                return -1;
1360        }
1361
1362        if (ctx->split) {
1363                char *lock_name = get_chain_filename(ctx->obj_dir);
1364
1365                hold_lock_file_for_update(&lk, lock_name, LOCK_DIE_ON_ERROR);
1366
1367                fd = git_mkstemp_mode(ctx->graph_name, 0444);
1368                if (fd < 0) {
1369                        error(_("unable to create '%s'"), ctx->graph_name);
1370                        return -1;
1371                }
1372
1373                f = hashfd(fd, ctx->graph_name);
1374        } else {
1375                hold_lock_file_for_update(&lk, ctx->graph_name, LOCK_DIE_ON_ERROR);
1376                fd = lk.tempfile->fd;
1377                f = hashfd(lk.tempfile->fd, lk.tempfile->filename.buf);
1378        }
1379
1380        chunk_ids[0] = GRAPH_CHUNKID_OIDFANOUT;
1381        chunk_ids[1] = GRAPH_CHUNKID_OIDLOOKUP;
1382        chunk_ids[2] = GRAPH_CHUNKID_DATA;
1383        if (ctx->num_extra_edges) {
1384                chunk_ids[num_chunks] = GRAPH_CHUNKID_EXTRAEDGES;
1385                num_chunks++;
1386        }
1387        if (ctx->num_commit_graphs_after > 1) {
1388                chunk_ids[num_chunks] = GRAPH_CHUNKID_BASE;
1389                num_chunks++;
1390        }
1391
1392        chunk_ids[num_chunks] = 0;
1393
1394        chunk_offsets[0] = 8 + (num_chunks + 1) * GRAPH_CHUNKLOOKUP_WIDTH;
1395        chunk_offsets[1] = chunk_offsets[0] + GRAPH_FANOUT_SIZE;
1396        chunk_offsets[2] = chunk_offsets[1] + hashsz * ctx->commits.nr;
1397        chunk_offsets[3] = chunk_offsets[2] + (hashsz + 16) * ctx->commits.nr;
1398
1399        num_chunks = 3;
1400        if (ctx->num_extra_edges) {
1401                chunk_offsets[num_chunks + 1] = chunk_offsets[num_chunks] +
1402                                                4 * ctx->num_extra_edges;
1403                num_chunks++;
1404        }
1405        if (ctx->num_commit_graphs_after > 1) {
1406                chunk_offsets[num_chunks + 1] = chunk_offsets[num_chunks] +
1407                                                hashsz * (ctx->num_commit_graphs_after - 1);
1408                num_chunks++;
1409        }
1410
1411        hashwrite_be32(f, GRAPH_SIGNATURE);
1412
1413        hashwrite_u8(f, GRAPH_VERSION);
1414        hashwrite_u8(f, oid_version());
1415        hashwrite_u8(f, num_chunks);
1416        hashwrite_u8(f, ctx->num_commit_graphs_after - 1);
1417
1418        for (i = 0; i <= num_chunks; i++) {
1419                uint32_t chunk_write[3];
1420
1421                chunk_write[0] = htonl(chunk_ids[i]);
1422                chunk_write[1] = htonl(chunk_offsets[i] >> 32);
1423                chunk_write[2] = htonl(chunk_offsets[i] & 0xffffffff);
1424                hashwrite(f, chunk_write, 12);
1425        }
1426
1427        if (ctx->report_progress) {
1428                strbuf_addf(&progress_title,
1429                            Q_("Writing out commit graph in %d pass",
1430                               "Writing out commit graph in %d passes",
1431                               num_chunks),
1432                            num_chunks);
1433                ctx->progress = start_delayed_progress(
1434                        progress_title.buf,
1435                        num_chunks * ctx->commits.nr);
1436        }
1437        write_graph_chunk_fanout(f, ctx);
1438        write_graph_chunk_oids(f, hashsz, ctx);
1439        write_graph_chunk_data(f, hashsz, ctx);
1440        if (ctx->num_extra_edges)
1441                write_graph_chunk_extra_edges(f, ctx);
1442        if (ctx->num_commit_graphs_after > 1 &&
1443            write_graph_chunk_base(f, ctx)) {
1444                return -1;
1445        }
1446        stop_progress(&ctx->progress);
1447        strbuf_release(&progress_title);
1448
1449        if (ctx->split && ctx->base_graph_name && ctx->num_commit_graphs_after > 1) {
1450                char *new_base_hash = xstrdup(oid_to_hex(&ctx->new_base_graph->oid));
1451                char *new_base_name = get_split_graph_filename(ctx->new_base_graph->obj_dir, new_base_hash);
1452
1453                free(ctx->commit_graph_filenames_after[ctx->num_commit_graphs_after - 2]);
1454                free(ctx->commit_graph_hash_after[ctx->num_commit_graphs_after - 2]);
1455                ctx->commit_graph_filenames_after[ctx->num_commit_graphs_after - 2] = new_base_name;
1456                ctx->commit_graph_hash_after[ctx->num_commit_graphs_after - 2] = new_base_hash;
1457        }
1458
1459        close_commit_graph(ctx->r->objects);
1460        finalize_hashfile(f, file_hash.hash, CSUM_HASH_IN_STREAM | CSUM_FSYNC);
1461
1462        if (ctx->split) {
1463                FILE *chainf = fdopen_lock_file(&lk, "w");
1464                char *final_graph_name;
1465                int result;
1466
1467                close(fd);
1468
1469                if (!chainf) {
1470                        error(_("unable to open commit-graph chain file"));
1471                        return -1;
1472                }
1473
1474                if (ctx->base_graph_name) {
1475                        const char *dest = ctx->commit_graph_filenames_after[
1476                                                ctx->num_commit_graphs_after - 2];
1477
1478                        if (strcmp(ctx->base_graph_name, dest)) {
1479                                result = rename(ctx->base_graph_name, dest);
1480
1481                                if (result) {
1482                                        error(_("failed to rename base commit-graph file"));
1483                                        return -1;
1484                                }
1485                        }
1486                } else {
1487                        char *graph_name = get_commit_graph_filename(ctx->obj_dir);
1488                        unlink(graph_name);
1489                }
1490
1491                ctx->commit_graph_hash_after[ctx->num_commit_graphs_after - 1] = xstrdup(oid_to_hex(&file_hash));
1492                final_graph_name = get_split_graph_filename(ctx->obj_dir,
1493                                        ctx->commit_graph_hash_after[ctx->num_commit_graphs_after - 1]);
1494                ctx->commit_graph_filenames_after[ctx->num_commit_graphs_after - 1] = final_graph_name;
1495
1496                result = rename(ctx->graph_name, final_graph_name);
1497
1498                for (i = 0; i < ctx->num_commit_graphs_after; i++)
1499                        fprintf(lk.tempfile->fp, "%s\n", ctx->commit_graph_hash_after[i]);
1500
1501                if (result) {
1502                        error(_("failed to rename temporary commit-graph file"));
1503                        return -1;
1504                }
1505        }
1506
1507        commit_lock_file(&lk);
1508
1509        return 0;
1510}
1511
1512static void split_graph_merge_strategy(struct write_commit_graph_context *ctx)
1513{
1514        struct commit_graph *g = ctx->r->objects->commit_graph;
1515        uint32_t num_commits = ctx->commits.nr;
1516        uint32_t i;
1517
1518        int max_commits = 0;
1519        int size_mult = 2;
1520
1521        if (ctx->split_opts) {
1522                max_commits = ctx->split_opts->max_commits;
1523                size_mult = ctx->split_opts->size_multiple;
1524        }
1525
1526        g = ctx->r->objects->commit_graph;
1527        ctx->num_commit_graphs_after = ctx->num_commit_graphs_before + 1;
1528
1529        while (g && (g->num_commits <= size_mult * num_commits ||
1530                    (max_commits && num_commits > max_commits))) {
1531                if (strcmp(g->obj_dir, ctx->obj_dir))
1532                        break;
1533
1534                num_commits += g->num_commits;
1535                g = g->base_graph;
1536
1537                ctx->num_commit_graphs_after--;
1538        }
1539
1540        ctx->new_base_graph = g;
1541
1542        if (ctx->num_commit_graphs_after == 2) {
1543                char *old_graph_name = get_commit_graph_filename(g->obj_dir);
1544
1545                if (!strcmp(g->filename, old_graph_name) &&
1546                    strcmp(g->obj_dir, ctx->obj_dir)) {
1547                        ctx->num_commit_graphs_after = 1;
1548                        ctx->new_base_graph = NULL;
1549                }
1550
1551                free(old_graph_name);
1552        }
1553
1554        ALLOC_ARRAY(ctx->commit_graph_filenames_after, ctx->num_commit_graphs_after);
1555        ALLOC_ARRAY(ctx->commit_graph_hash_after, ctx->num_commit_graphs_after);
1556
1557        for (i = 0; i < ctx->num_commit_graphs_after &&
1558                    i < ctx->num_commit_graphs_before; i++)
1559                ctx->commit_graph_filenames_after[i] = xstrdup(ctx->commit_graph_filenames_before[i]);
1560
1561        i = ctx->num_commit_graphs_before - 1;
1562        g = ctx->r->objects->commit_graph;
1563
1564        while (g) {
1565                if (i < ctx->num_commit_graphs_after)
1566                        ctx->commit_graph_hash_after[i] = xstrdup(oid_to_hex(&g->oid));
1567
1568                i--;
1569                g = g->base_graph;
1570        }
1571}
1572
1573static void merge_commit_graph(struct write_commit_graph_context *ctx,
1574                               struct commit_graph *g)
1575{
1576        uint32_t i;
1577        uint32_t offset = g->num_commits_in_base;
1578
1579        ALLOC_GROW(ctx->commits.list, ctx->commits.nr + g->num_commits, ctx->commits.alloc);
1580
1581        for (i = 0; i < g->num_commits; i++) {
1582                struct object_id oid;
1583                struct commit *result;
1584
1585                display_progress(ctx->progress, i + 1);
1586
1587                load_oid_from_graph(g, i + offset, &oid);
1588
1589                /* only add commits if they still exist in the repo */
1590                result = lookup_commit_reference_gently(ctx->r, &oid, 1);
1591
1592                if (result) {
1593                        ctx->commits.list[ctx->commits.nr] = result;
1594                        ctx->commits.nr++;
1595                }
1596        }
1597}
1598
1599static int commit_compare(const void *_a, const void *_b)
1600{
1601        const struct commit *a = *(const struct commit **)_a;
1602        const struct commit *b = *(const struct commit **)_b;
1603        return oidcmp(&a->object.oid, &b->object.oid);
1604}
1605
1606static void sort_and_scan_merged_commits(struct write_commit_graph_context *ctx)
1607{
1608        uint32_t i, num_parents;
1609        struct commit_list *parent;
1610
1611        if (ctx->report_progress)
1612                ctx->progress = start_delayed_progress(
1613                                        _("Scanning merged commits"),
1614                                        ctx->commits.nr);
1615
1616        QSORT(ctx->commits.list, ctx->commits.nr, commit_compare);
1617
1618        ctx->num_extra_edges = 0;
1619        for (i = 0; i < ctx->commits.nr; i++) {
1620                display_progress(ctx->progress, i);
1621
1622                if (i && oideq(&ctx->commits.list[i - 1]->object.oid,
1623                          &ctx->commits.list[i]->object.oid)) {
1624                        die(_("unexpected duplicate commit id %s"),
1625                            oid_to_hex(&ctx->commits.list[i]->object.oid));
1626                } else {
1627                        num_parents = 0;
1628                        for (parent = ctx->commits.list[i]->parents; parent; parent = parent->next)
1629                                num_parents++;
1630
1631                        if (num_parents > 2)
1632                                ctx->num_extra_edges += num_parents - 2;
1633                }
1634        }
1635
1636        stop_progress(&ctx->progress);
1637}
1638
1639static void merge_commit_graphs(struct write_commit_graph_context *ctx)
1640{
1641        struct commit_graph *g = ctx->r->objects->commit_graph;
1642        uint32_t current_graph_number = ctx->num_commit_graphs_before;
1643        struct strbuf progress_title = STRBUF_INIT;
1644
1645        while (g && current_graph_number >= ctx->num_commit_graphs_after) {
1646                current_graph_number--;
1647
1648                if (ctx->report_progress) {
1649                        strbuf_addstr(&progress_title, _("Merging commit-graph"));
1650                        ctx->progress = start_delayed_progress(progress_title.buf, 0);
1651                }
1652
1653                merge_commit_graph(ctx, g);
1654                stop_progress(&ctx->progress);
1655                strbuf_release(&progress_title);
1656
1657                g = g->base_graph;
1658        }
1659
1660        if (g) {
1661                ctx->new_base_graph = g;
1662                ctx->new_num_commits_in_base = g->num_commits + g->num_commits_in_base;
1663        }
1664
1665        if (ctx->new_base_graph)
1666                ctx->base_graph_name = xstrdup(ctx->new_base_graph->filename);
1667
1668        sort_and_scan_merged_commits(ctx);
1669}
1670
1671static void mark_commit_graphs(struct write_commit_graph_context *ctx)
1672{
1673        uint32_t i;
1674        time_t now = time(NULL);
1675
1676        for (i = ctx->num_commit_graphs_after - 1; i < ctx->num_commit_graphs_before; i++) {
1677                struct stat st;
1678                struct utimbuf updated_time;
1679
1680                stat(ctx->commit_graph_filenames_before[i], &st);
1681
1682                updated_time.actime = st.st_atime;
1683                updated_time.modtime = now;
1684                utime(ctx->commit_graph_filenames_before[i], &updated_time);
1685        }
1686}
1687
1688static void expire_commit_graphs(struct write_commit_graph_context *ctx)
1689{
1690        struct strbuf path = STRBUF_INIT;
1691        DIR *dir;
1692        struct dirent *de;
1693        size_t dirnamelen;
1694        timestamp_t expire_time = time(NULL);
1695
1696        if (ctx->split_opts && ctx->split_opts->expire_time)
1697                expire_time -= ctx->split_opts->expire_time;
1698        if (!ctx->split) {
1699                char *chain_file_name = get_chain_filename(ctx->obj_dir);
1700                unlink(chain_file_name);
1701                free(chain_file_name);
1702                ctx->num_commit_graphs_after = 0;
1703        }
1704
1705        strbuf_addstr(&path, ctx->obj_dir);
1706        strbuf_addstr(&path, "/info/commit-graphs");
1707        dir = opendir(path.buf);
1708
1709        if (!dir) {
1710                strbuf_release(&path);
1711                return;
1712        }
1713
1714        strbuf_addch(&path, '/');
1715        dirnamelen = path.len;
1716        while ((de = readdir(dir)) != NULL) {
1717                struct stat st;
1718                uint32_t i, found = 0;
1719
1720                strbuf_setlen(&path, dirnamelen);
1721                strbuf_addstr(&path, de->d_name);
1722
1723                stat(path.buf, &st);
1724
1725                if (st.st_mtime > expire_time)
1726                        continue;
1727                if (path.len < 6 || strcmp(path.buf + path.len - 6, ".graph"))
1728                        continue;
1729
1730                for (i = 0; i < ctx->num_commit_graphs_after; i++) {
1731                        if (!strcmp(ctx->commit_graph_filenames_after[i],
1732                                    path.buf)) {
1733                                found = 1;
1734                                break;
1735                        }
1736                }
1737
1738                if (!found)
1739                        unlink(path.buf);
1740        }
1741}
1742
1743int write_commit_graph(const char *obj_dir,
1744                       struct string_list *pack_indexes,
1745                       struct string_list *commit_hex,
1746                       unsigned int flags,
1747                       const struct split_commit_graph_opts *split_opts)
1748{
1749        struct write_commit_graph_context *ctx;
1750        uint32_t i, count_distinct = 0;
1751        size_t len;
1752        int res = 0;
1753
1754        if (!commit_graph_compatible(the_repository))
1755                return 0;
1756
1757        ctx = xcalloc(1, sizeof(struct write_commit_graph_context));
1758        ctx->r = the_repository;
1759
1760        /* normalize object dir with no trailing slash */
1761        ctx->obj_dir = xmallocz(strlen(obj_dir) + 1);
1762        normalize_path_copy(ctx->obj_dir, obj_dir);
1763        len = strlen(ctx->obj_dir);
1764        if (len && ctx->obj_dir[len - 1] == '/')
1765                ctx->obj_dir[len - 1] = 0;
1766
1767        ctx->append = flags & COMMIT_GRAPH_APPEND ? 1 : 0;
1768        ctx->report_progress = flags & COMMIT_GRAPH_PROGRESS ? 1 : 0;
1769        ctx->split = flags & COMMIT_GRAPH_SPLIT ? 1 : 0;
1770        ctx->split_opts = split_opts;
1771
1772        if (ctx->split) {
1773                struct commit_graph *g;
1774                prepare_commit_graph(ctx->r);
1775
1776                g = ctx->r->objects->commit_graph;
1777
1778                while (g) {
1779                        ctx->num_commit_graphs_before++;
1780                        g = g->base_graph;
1781                }
1782
1783                if (ctx->num_commit_graphs_before) {
1784                        ALLOC_ARRAY(ctx->commit_graph_filenames_before, ctx->num_commit_graphs_before);
1785                        i = ctx->num_commit_graphs_before;
1786                        g = ctx->r->objects->commit_graph;
1787
1788                        while (g) {
1789                                ctx->commit_graph_filenames_before[--i] = xstrdup(g->filename);
1790                                g = g->base_graph;
1791                        }
1792                }
1793        }
1794
1795        ctx->approx_nr_objects = approximate_object_count();
1796        ctx->oids.alloc = ctx->approx_nr_objects / 32;
1797
1798        if (ctx->split && split_opts && ctx->oids.alloc > split_opts->max_commits)
1799                ctx->oids.alloc = split_opts->max_commits;
1800
1801        if (ctx->append) {
1802                prepare_commit_graph_one(ctx->r, ctx->obj_dir);
1803                if (ctx->r->objects->commit_graph)
1804                        ctx->oids.alloc += ctx->r->objects->commit_graph->num_commits;
1805        }
1806
1807        if (ctx->oids.alloc < 1024)
1808                ctx->oids.alloc = 1024;
1809        ALLOC_ARRAY(ctx->oids.list, ctx->oids.alloc);
1810
1811        if (ctx->append && ctx->r->objects->commit_graph) {
1812                struct commit_graph *g = ctx->r->objects->commit_graph;
1813                for (i = 0; i < g->num_commits; i++) {
1814                        const unsigned char *hash = g->chunk_oid_lookup + g->hash_len * i;
1815                        hashcpy(ctx->oids.list[ctx->oids.nr++].hash, hash);
1816                }
1817        }
1818
1819        if (pack_indexes) {
1820                if ((res = fill_oids_from_packs(ctx, pack_indexes)))
1821                        goto cleanup;
1822        }
1823
1824        if (commit_hex)
1825                fill_oids_from_commit_hex(ctx, commit_hex);
1826
1827        if (!pack_indexes && !commit_hex)
1828                fill_oids_from_all_packs(ctx);
1829
1830        close_reachable(ctx);
1831
1832        count_distinct = count_distinct_commits(ctx);
1833
1834        if (count_distinct >= GRAPH_EDGE_LAST_MASK) {
1835                error(_("the commit graph format cannot write %d commits"), count_distinct);
1836                res = -1;
1837                goto cleanup;
1838        }
1839
1840        ctx->commits.alloc = count_distinct;
1841        ALLOC_ARRAY(ctx->commits.list, ctx->commits.alloc);
1842
1843        copy_oids_to_commits(ctx);
1844
1845        if (ctx->commits.nr >= GRAPH_EDGE_LAST_MASK) {
1846                error(_("too many commits to write graph"));
1847                res = -1;
1848                goto cleanup;
1849        }
1850
1851        if (!ctx->commits.nr)
1852                goto cleanup;
1853
1854        if (ctx->split) {
1855                split_graph_merge_strategy(ctx);
1856
1857                merge_commit_graphs(ctx);
1858        } else
1859                ctx->num_commit_graphs_after = 1;
1860
1861        compute_generation_numbers(ctx);
1862
1863        res = write_commit_graph_file(ctx);
1864
1865        if (ctx->split)
1866                mark_commit_graphs(ctx);
1867
1868        expire_commit_graphs(ctx);
1869
1870cleanup:
1871        free(ctx->graph_name);
1872        free(ctx->commits.list);
1873        free(ctx->oids.list);
1874        free(ctx->obj_dir);
1875
1876        if (ctx->commit_graph_filenames_after) {
1877                for (i = 0; i < ctx->num_commit_graphs_after; i++) {
1878                        free(ctx->commit_graph_filenames_after[i]);
1879                        free(ctx->commit_graph_hash_after[i]);
1880                }
1881
1882                for (i = 0; i < ctx->num_commit_graphs_before; i++)
1883                        free(ctx->commit_graph_filenames_before[i]);
1884
1885                free(ctx->commit_graph_filenames_after);
1886                free(ctx->commit_graph_filenames_before);
1887                free(ctx->commit_graph_hash_after);
1888        }
1889
1890        free(ctx);
1891
1892        return res;
1893}
1894
1895#define VERIFY_COMMIT_GRAPH_ERROR_HASH 2
1896static int verify_commit_graph_error;
1897
1898static void graph_report(const char *fmt, ...)
1899{
1900        va_list ap;
1901
1902        verify_commit_graph_error = 1;
1903        va_start(ap, fmt);
1904        vfprintf(stderr, fmt, ap);
1905        fprintf(stderr, "\n");
1906        va_end(ap);
1907}
1908
1909#define GENERATION_ZERO_EXISTS 1
1910#define GENERATION_NUMBER_EXISTS 2
1911
1912int verify_commit_graph(struct repository *r, struct commit_graph *g, int flags)
1913{
1914        uint32_t i, cur_fanout_pos = 0;
1915        struct object_id prev_oid, cur_oid, checksum;
1916        int generation_zero = 0;
1917        struct hashfile *f;
1918        int devnull;
1919        struct progress *progress = NULL;
1920        int local_error = 0;
1921
1922        if (!g) {
1923                graph_report("no commit-graph file loaded");
1924                return 1;
1925        }
1926
1927        verify_commit_graph_error = verify_commit_graph_lite(g);
1928        if (verify_commit_graph_error)
1929                return verify_commit_graph_error;
1930
1931        devnull = open("/dev/null", O_WRONLY);
1932        f = hashfd(devnull, NULL);
1933        hashwrite(f, g->data, g->data_len - g->hash_len);
1934        finalize_hashfile(f, checksum.hash, CSUM_CLOSE);
1935        if (!hasheq(checksum.hash, g->data + g->data_len - g->hash_len)) {
1936                graph_report(_("the commit-graph file has incorrect checksum and is likely corrupt"));
1937                verify_commit_graph_error = VERIFY_COMMIT_GRAPH_ERROR_HASH;
1938        }
1939
1940        for (i = 0; i < g->num_commits; i++) {
1941                struct commit *graph_commit;
1942
1943                hashcpy(cur_oid.hash, g->chunk_oid_lookup + g->hash_len * i);
1944
1945                if (i && oidcmp(&prev_oid, &cur_oid) >= 0)
1946                        graph_report(_("commit-graph has incorrect OID order: %s then %s"),
1947                                     oid_to_hex(&prev_oid),
1948                                     oid_to_hex(&cur_oid));
1949
1950                oidcpy(&prev_oid, &cur_oid);
1951
1952                while (cur_oid.hash[0] > cur_fanout_pos) {
1953                        uint32_t fanout_value = get_be32(g->chunk_oid_fanout + cur_fanout_pos);
1954
1955                        if (i != fanout_value)
1956                                graph_report(_("commit-graph has incorrect fanout value: fanout[%d] = %u != %u"),
1957                                             cur_fanout_pos, fanout_value, i);
1958                        cur_fanout_pos++;
1959                }
1960
1961                graph_commit = lookup_commit(r, &cur_oid);
1962                if (!parse_commit_in_graph_one(r, g, graph_commit))
1963                        graph_report(_("failed to parse commit %s from commit-graph"),
1964                                     oid_to_hex(&cur_oid));
1965        }
1966
1967        while (cur_fanout_pos < 256) {
1968                uint32_t fanout_value = get_be32(g->chunk_oid_fanout + cur_fanout_pos);
1969
1970                if (g->num_commits != fanout_value)
1971                        graph_report(_("commit-graph has incorrect fanout value: fanout[%d] = %u != %u"),
1972                                     cur_fanout_pos, fanout_value, i);
1973
1974                cur_fanout_pos++;
1975        }
1976
1977        if (verify_commit_graph_error & ~VERIFY_COMMIT_GRAPH_ERROR_HASH)
1978                return verify_commit_graph_error;
1979
1980        progress = start_progress(_("Verifying commits in commit graph"),
1981                                  g->num_commits);
1982        for (i = 0; i < g->num_commits; i++) {
1983                struct commit *graph_commit, *odb_commit;
1984                struct commit_list *graph_parents, *odb_parents;
1985                uint32_t max_generation = 0;
1986
1987                display_progress(progress, i + 1);
1988                hashcpy(cur_oid.hash, g->chunk_oid_lookup + g->hash_len * i);
1989
1990                graph_commit = lookup_commit(r, &cur_oid);
1991                odb_commit = (struct commit *)create_object(r, cur_oid.hash, alloc_commit_node(r));
1992                if (parse_commit_internal(odb_commit, 0, 0)) {
1993                        graph_report(_("failed to parse commit %s from object database for commit-graph"),
1994                                     oid_to_hex(&cur_oid));
1995                        continue;
1996                }
1997
1998                if (!oideq(&get_commit_tree_in_graph_one(r, g, graph_commit)->object.oid,
1999                           get_commit_tree_oid(odb_commit)))
2000                        graph_report(_("root tree OID for commit %s in commit-graph is %s != %s"),
2001                                     oid_to_hex(&cur_oid),
2002                                     oid_to_hex(get_commit_tree_oid(graph_commit)),
2003                                     oid_to_hex(get_commit_tree_oid(odb_commit)));
2004
2005                graph_parents = graph_commit->parents;
2006                odb_parents = odb_commit->parents;
2007
2008                while (graph_parents) {
2009                        if (odb_parents == NULL) {
2010                                graph_report(_("commit-graph parent list for commit %s is too long"),
2011                                             oid_to_hex(&cur_oid));
2012                                break;
2013                        }
2014
2015                        /* parse parent in case it is in a base graph */
2016                        parse_commit_in_graph_one(r, g, graph_parents->item);
2017
2018                        if (!oideq(&graph_parents->item->object.oid, &odb_parents->item->object.oid))
2019                                graph_report(_("commit-graph parent for %s is %s != %s"),
2020                                             oid_to_hex(&cur_oid),
2021                                             oid_to_hex(&graph_parents->item->object.oid),
2022                                             oid_to_hex(&odb_parents->item->object.oid));
2023
2024                        if (graph_parents->item->generation > max_generation)
2025                                max_generation = graph_parents->item->generation;
2026
2027                        graph_parents = graph_parents->next;
2028                        odb_parents = odb_parents->next;
2029                }
2030
2031                if (odb_parents != NULL)
2032                        graph_report(_("commit-graph parent list for commit %s terminates early"),
2033                                     oid_to_hex(&cur_oid));
2034
2035                if (!graph_commit->generation) {
2036                        if (generation_zero == GENERATION_NUMBER_EXISTS)
2037                                graph_report(_("commit-graph has generation number zero for commit %s, but non-zero elsewhere"),
2038                                             oid_to_hex(&cur_oid));
2039                        generation_zero = GENERATION_ZERO_EXISTS;
2040                } else if (generation_zero == GENERATION_ZERO_EXISTS)
2041                        graph_report(_("commit-graph has non-zero generation number for commit %s, but zero elsewhere"),
2042                                     oid_to_hex(&cur_oid));
2043
2044                if (generation_zero == GENERATION_ZERO_EXISTS)
2045                        continue;
2046
2047                /*
2048                 * If one of our parents has generation GENERATION_NUMBER_MAX, then
2049                 * our generation is also GENERATION_NUMBER_MAX. Decrement to avoid
2050                 * extra logic in the following condition.
2051                 */
2052                if (max_generation == GENERATION_NUMBER_MAX)
2053                        max_generation--;
2054
2055                if (graph_commit->generation != max_generation + 1)
2056                        graph_report(_("commit-graph generation for commit %s is %u != %u"),
2057                                     oid_to_hex(&cur_oid),
2058                                     graph_commit->generation,
2059                                     max_generation + 1);
2060
2061                if (graph_commit->date != odb_commit->date)
2062                        graph_report(_("commit date for commit %s in commit-graph is %"PRItime" != %"PRItime),
2063                                     oid_to_hex(&cur_oid),
2064                                     graph_commit->date,
2065                                     odb_commit->date);
2066        }
2067        stop_progress(&progress);
2068
2069        local_error = verify_commit_graph_error;
2070
2071        if (!(flags & COMMIT_GRAPH_VERIFY_SHALLOW) && g->base_graph)
2072                local_error |= verify_commit_graph(r, g->base_graph, flags);
2073
2074        return local_error;
2075}
2076
2077void free_commit_graph(struct commit_graph *g)
2078{
2079        if (!g)
2080                return;
2081        if (g->graph_fd >= 0) {
2082                munmap((void *)g->data, g->data_len);
2083                g->data = NULL;
2084                close(g->graph_fd);
2085        }
2086        free(g->filename);
2087        free(g);
2088}