builtin / index-pack.con commit Merge branch 'rs/pp-user-info-without-extra-allocation' (d9291ec)
   1#include "builtin.h"
   2#include "delta.h"
   3#include "pack.h"
   4#include "csum-file.h"
   5#include "blob.h"
   6#include "commit.h"
   7#include "tag.h"
   8#include "tree.h"
   9#include "progress.h"
  10#include "fsck.h"
  11#include "exec_cmd.h"
  12#include "streaming.h"
  13#include "thread-utils.h"
  14
  15static const char index_pack_usage[] =
  16"git index-pack [-v] [-o <index-file>] [--keep | --keep=<msg>] [--verify] [--strict] (<pack-file> | --stdin [--fix-thin] [<pack-file>])";
  17
  18struct object_entry {
  19        struct pack_idx_entry idx;
  20        unsigned long size;
  21        unsigned int hdr_size;
  22        enum object_type type;
  23        enum object_type real_type;
  24        unsigned delta_depth;
  25        int base_object_no;
  26};
  27
  28union delta_base {
  29        unsigned char sha1[20];
  30        off_t offset;
  31};
  32
  33struct base_data {
  34        struct base_data *base;
  35        struct base_data *child;
  36        struct object_entry *obj;
  37        void *data;
  38        unsigned long size;
  39        int ref_first, ref_last;
  40        int ofs_first, ofs_last;
  41};
  42
  43#if !defined(NO_PTHREADS) && defined(NO_THREAD_SAFE_PREAD)
  44/* pread() emulation is not thread-safe. Disable threading. */
  45#define NO_PTHREADS
  46#endif
  47
  48struct thread_local {
  49#ifndef NO_PTHREADS
  50        pthread_t thread;
  51#endif
  52        struct base_data *base_cache;
  53        size_t base_cache_used;
  54};
  55
  56/*
  57 * Even if sizeof(union delta_base) == 24 on 64-bit archs, we really want
  58 * to memcmp() only the first 20 bytes.
  59 */
  60#define UNION_BASE_SZ   20
  61
  62#define FLAG_LINK (1u<<20)
  63#define FLAG_CHECKED (1u<<21)
  64
  65struct delta_entry {
  66        union delta_base base;
  67        int obj_no;
  68};
  69
  70static struct object_entry *objects;
  71static struct delta_entry *deltas;
  72static struct thread_local nothread_data;
  73static int nr_objects;
  74static int nr_deltas;
  75static int nr_resolved_deltas;
  76static int nr_threads;
  77
  78static int from_stdin;
  79static int strict;
  80static int verbose;
  81static int show_stat;
  82
  83static struct progress *progress;
  84
  85/* We always read in 4kB chunks. */
  86static unsigned char input_buffer[4096];
  87static unsigned int input_offset, input_len;
  88static off_t consumed_bytes;
  89static unsigned deepest_delta;
  90static git_SHA_CTX input_ctx;
  91static uint32_t input_crc32;
  92static int input_fd, output_fd, pack_fd;
  93
  94#ifndef NO_PTHREADS
  95
  96static struct thread_local *thread_data;
  97static int nr_dispatched;
  98static int threads_active;
  99
 100static pthread_mutex_t read_mutex;
 101#define read_lock()             lock_mutex(&read_mutex)
 102#define read_unlock()           unlock_mutex(&read_mutex)
 103
 104static pthread_mutex_t counter_mutex;
 105#define counter_lock()          lock_mutex(&counter_mutex)
 106#define counter_unlock()        unlock_mutex(&counter_mutex)
 107
 108static pthread_mutex_t work_mutex;
 109#define work_lock()             lock_mutex(&work_mutex)
 110#define work_unlock()           unlock_mutex(&work_mutex)
 111
 112static pthread_mutex_t deepest_delta_mutex;
 113#define deepest_delta_lock()    lock_mutex(&deepest_delta_mutex)
 114#define deepest_delta_unlock()  unlock_mutex(&deepest_delta_mutex)
 115
 116static pthread_key_t key;
 117
 118static inline void lock_mutex(pthread_mutex_t *mutex)
 119{
 120        if (threads_active)
 121                pthread_mutex_lock(mutex);
 122}
 123
 124static inline void unlock_mutex(pthread_mutex_t *mutex)
 125{
 126        if (threads_active)
 127                pthread_mutex_unlock(mutex);
 128}
 129
 130/*
 131 * Mutex and conditional variable can't be statically-initialized on Windows.
 132 */
 133static void init_thread(void)
 134{
 135        init_recursive_mutex(&read_mutex);
 136        pthread_mutex_init(&counter_mutex, NULL);
 137        pthread_mutex_init(&work_mutex, NULL);
 138        if (show_stat)
 139                pthread_mutex_init(&deepest_delta_mutex, NULL);
 140        pthread_key_create(&key, NULL);
 141        thread_data = xcalloc(nr_threads, sizeof(*thread_data));
 142        threads_active = 1;
 143}
 144
 145static void cleanup_thread(void)
 146{
 147        if (!threads_active)
 148                return;
 149        threads_active = 0;
 150        pthread_mutex_destroy(&read_mutex);
 151        pthread_mutex_destroy(&counter_mutex);
 152        pthread_mutex_destroy(&work_mutex);
 153        if (show_stat)
 154                pthread_mutex_destroy(&deepest_delta_mutex);
 155        pthread_key_delete(key);
 156        free(thread_data);
 157}
 158
 159#else
 160
 161#define read_lock()
 162#define read_unlock()
 163
 164#define counter_lock()
 165#define counter_unlock()
 166
 167#define work_lock()
 168#define work_unlock()
 169
 170#define deepest_delta_lock()
 171#define deepest_delta_unlock()
 172
 173#endif
 174
 175
 176static int mark_link(struct object *obj, int type, void *data)
 177{
 178        if (!obj)
 179                return -1;
 180
 181        if (type != OBJ_ANY && obj->type != type)
 182                die(_("object type mismatch at %s"), sha1_to_hex(obj->sha1));
 183
 184        obj->flags |= FLAG_LINK;
 185        return 0;
 186}
 187
 188/* The content of each linked object must have been checked
 189   or it must be already present in the object database */
 190static void check_object(struct object *obj)
 191{
 192        if (!obj)
 193                return;
 194
 195        if (!(obj->flags & FLAG_LINK))
 196                return;
 197
 198        if (!(obj->flags & FLAG_CHECKED)) {
 199                unsigned long size;
 200                int type = sha1_object_info(obj->sha1, &size);
 201                if (type != obj->type || type <= 0)
 202                        die(_("object of unexpected type"));
 203                obj->flags |= FLAG_CHECKED;
 204                return;
 205        }
 206}
 207
 208static void check_objects(void)
 209{
 210        unsigned i, max;
 211
 212        max = get_max_object_index();
 213        for (i = 0; i < max; i++)
 214                check_object(get_indexed_object(i));
 215}
 216
 217
 218/* Discard current buffer used content. */
 219static void flush(void)
 220{
 221        if (input_offset) {
 222                if (output_fd >= 0)
 223                        write_or_die(output_fd, input_buffer, input_offset);
 224                git_SHA1_Update(&input_ctx, input_buffer, input_offset);
 225                memmove(input_buffer, input_buffer + input_offset, input_len);
 226                input_offset = 0;
 227        }
 228}
 229
 230/*
 231 * Make sure at least "min" bytes are available in the buffer, and
 232 * return the pointer to the buffer.
 233 */
 234static void *fill(int min)
 235{
 236        if (min <= input_len)
 237                return input_buffer + input_offset;
 238        if (min > sizeof(input_buffer))
 239                die(Q_("cannot fill %d byte",
 240                       "cannot fill %d bytes",
 241                       min),
 242                    min);
 243        flush();
 244        do {
 245                ssize_t ret = xread(input_fd, input_buffer + input_len,
 246                                sizeof(input_buffer) - input_len);
 247                if (ret <= 0) {
 248                        if (!ret)
 249                                die(_("early EOF"));
 250                        die_errno(_("read error on input"));
 251                }
 252                input_len += ret;
 253                if (from_stdin)
 254                        display_throughput(progress, consumed_bytes + input_len);
 255        } while (input_len < min);
 256        return input_buffer;
 257}
 258
 259static void use(int bytes)
 260{
 261        if (bytes > input_len)
 262                die(_("used more bytes than were available"));
 263        input_crc32 = crc32(input_crc32, input_buffer + input_offset, bytes);
 264        input_len -= bytes;
 265        input_offset += bytes;
 266
 267        /* make sure off_t is sufficiently large not to wrap */
 268        if (signed_add_overflows(consumed_bytes, bytes))
 269                die(_("pack too large for current definition of off_t"));
 270        consumed_bytes += bytes;
 271}
 272
 273static const char *open_pack_file(const char *pack_name)
 274{
 275        if (from_stdin) {
 276                input_fd = 0;
 277                if (!pack_name) {
 278                        static char tmp_file[PATH_MAX];
 279                        output_fd = odb_mkstemp(tmp_file, sizeof(tmp_file),
 280                                                "pack/tmp_pack_XXXXXX");
 281                        pack_name = xstrdup(tmp_file);
 282                } else
 283                        output_fd = open(pack_name, O_CREAT|O_EXCL|O_RDWR, 0600);
 284                if (output_fd < 0)
 285                        die_errno(_("unable to create '%s'"), pack_name);
 286                pack_fd = output_fd;
 287        } else {
 288                input_fd = open(pack_name, O_RDONLY);
 289                if (input_fd < 0)
 290                        die_errno(_("cannot open packfile '%s'"), pack_name);
 291                output_fd = -1;
 292                pack_fd = input_fd;
 293        }
 294        git_SHA1_Init(&input_ctx);
 295        return pack_name;
 296}
 297
 298static void parse_pack_header(void)
 299{
 300        struct pack_header *hdr = fill(sizeof(struct pack_header));
 301
 302        /* Header consistency check */
 303        if (hdr->hdr_signature != htonl(PACK_SIGNATURE))
 304                die(_("pack signature mismatch"));
 305        if (!pack_version_ok(hdr->hdr_version))
 306                die(_("pack version %"PRIu32" unsupported"),
 307                        ntohl(hdr->hdr_version));
 308
 309        nr_objects = ntohl(hdr->hdr_entries);
 310        use(sizeof(struct pack_header));
 311}
 312
 313static NORETURN void bad_object(unsigned long offset, const char *format,
 314                       ...) __attribute__((format (printf, 2, 3)));
 315
 316static NORETURN void bad_object(unsigned long offset, const char *format, ...)
 317{
 318        va_list params;
 319        char buf[1024];
 320
 321        va_start(params, format);
 322        vsnprintf(buf, sizeof(buf), format, params);
 323        va_end(params);
 324        die(_("pack has bad object at offset %lu: %s"), offset, buf);
 325}
 326
 327static inline struct thread_local *get_thread_data(void)
 328{
 329#ifndef NO_PTHREADS
 330        if (threads_active)
 331                return pthread_getspecific(key);
 332        assert(!threads_active &&
 333               "This should only be reached when all threads are gone");
 334#endif
 335        return &nothread_data;
 336}
 337
 338#ifndef NO_PTHREADS
 339static void set_thread_data(struct thread_local *data)
 340{
 341        if (threads_active)
 342                pthread_setspecific(key, data);
 343}
 344#endif
 345
 346static struct base_data *alloc_base_data(void)
 347{
 348        struct base_data *base = xmalloc(sizeof(struct base_data));
 349        memset(base, 0, sizeof(*base));
 350        base->ref_last = -1;
 351        base->ofs_last = -1;
 352        return base;
 353}
 354
 355static void free_base_data(struct base_data *c)
 356{
 357        if (c->data) {
 358                free(c->data);
 359                c->data = NULL;
 360                get_thread_data()->base_cache_used -= c->size;
 361        }
 362}
 363
 364static void prune_base_data(struct base_data *retain)
 365{
 366        struct base_data *b;
 367        struct thread_local *data = get_thread_data();
 368        for (b = data->base_cache;
 369             data->base_cache_used > delta_base_cache_limit && b;
 370             b = b->child) {
 371                if (b->data && b != retain)
 372                        free_base_data(b);
 373        }
 374}
 375
 376static void link_base_data(struct base_data *base, struct base_data *c)
 377{
 378        if (base)
 379                base->child = c;
 380        else
 381                get_thread_data()->base_cache = c;
 382
 383        c->base = base;
 384        c->child = NULL;
 385        if (c->data)
 386                get_thread_data()->base_cache_used += c->size;
 387        prune_base_data(c);
 388}
 389
 390static void unlink_base_data(struct base_data *c)
 391{
 392        struct base_data *base = c->base;
 393        if (base)
 394                base->child = NULL;
 395        else
 396                get_thread_data()->base_cache = NULL;
 397        free_base_data(c);
 398}
 399
 400static int is_delta_type(enum object_type type)
 401{
 402        return (type == OBJ_REF_DELTA || type == OBJ_OFS_DELTA);
 403}
 404
 405static void *unpack_entry_data(unsigned long offset, unsigned long size,
 406                               enum object_type type, unsigned char *sha1)
 407{
 408        static char fixed_buf[8192];
 409        int status;
 410        git_zstream stream;
 411        void *buf;
 412        git_SHA_CTX c;
 413        char hdr[32];
 414        int hdrlen;
 415
 416        if (!is_delta_type(type)) {
 417                hdrlen = sprintf(hdr, "%s %lu", typename(type), size) + 1;
 418                git_SHA1_Init(&c);
 419                git_SHA1_Update(&c, hdr, hdrlen);
 420        } else
 421                sha1 = NULL;
 422        if (type == OBJ_BLOB && size > big_file_threshold)
 423                buf = fixed_buf;
 424        else
 425                buf = xmalloc(size);
 426
 427        memset(&stream, 0, sizeof(stream));
 428        git_inflate_init(&stream);
 429        stream.next_out = buf;
 430        stream.avail_out = buf == fixed_buf ? sizeof(fixed_buf) : size;
 431
 432        do {
 433                unsigned char *last_out = stream.next_out;
 434                stream.next_in = fill(1);
 435                stream.avail_in = input_len;
 436                status = git_inflate(&stream, 0);
 437                use(input_len - stream.avail_in);
 438                if (sha1)
 439                        git_SHA1_Update(&c, last_out, stream.next_out - last_out);
 440                if (buf == fixed_buf) {
 441                        stream.next_out = buf;
 442                        stream.avail_out = sizeof(fixed_buf);
 443                }
 444        } while (status == Z_OK);
 445        if (stream.total_out != size || status != Z_STREAM_END)
 446                bad_object(offset, _("inflate returned %d"), status);
 447        git_inflate_end(&stream);
 448        if (sha1)
 449                git_SHA1_Final(sha1, &c);
 450        return buf == fixed_buf ? NULL : buf;
 451}
 452
 453static void *unpack_raw_entry(struct object_entry *obj,
 454                              union delta_base *delta_base,
 455                              unsigned char *sha1)
 456{
 457        unsigned char *p;
 458        unsigned long size, c;
 459        off_t base_offset;
 460        unsigned shift;
 461        void *data;
 462
 463        obj->idx.offset = consumed_bytes;
 464        input_crc32 = crc32(0, NULL, 0);
 465
 466        p = fill(1);
 467        c = *p;
 468        use(1);
 469        obj->type = (c >> 4) & 7;
 470        size = (c & 15);
 471        shift = 4;
 472        while (c & 0x80) {
 473                p = fill(1);
 474                c = *p;
 475                use(1);
 476                size += (c & 0x7f) << shift;
 477                shift += 7;
 478        }
 479        obj->size = size;
 480
 481        switch (obj->type) {
 482        case OBJ_REF_DELTA:
 483                hashcpy(delta_base->sha1, fill(20));
 484                use(20);
 485                break;
 486        case OBJ_OFS_DELTA:
 487                memset(delta_base, 0, sizeof(*delta_base));
 488                p = fill(1);
 489                c = *p;
 490                use(1);
 491                base_offset = c & 127;
 492                while (c & 128) {
 493                        base_offset += 1;
 494                        if (!base_offset || MSB(base_offset, 7))
 495                                bad_object(obj->idx.offset, _("offset value overflow for delta base object"));
 496                        p = fill(1);
 497                        c = *p;
 498                        use(1);
 499                        base_offset = (base_offset << 7) + (c & 127);
 500                }
 501                delta_base->offset = obj->idx.offset - base_offset;
 502                if (delta_base->offset <= 0 || delta_base->offset >= obj->idx.offset)
 503                        bad_object(obj->idx.offset, _("delta base offset is out of bound"));
 504                break;
 505        case OBJ_COMMIT:
 506        case OBJ_TREE:
 507        case OBJ_BLOB:
 508        case OBJ_TAG:
 509                break;
 510        default:
 511                bad_object(obj->idx.offset, _("unknown object type %d"), obj->type);
 512        }
 513        obj->hdr_size = consumed_bytes - obj->idx.offset;
 514
 515        data = unpack_entry_data(obj->idx.offset, obj->size, obj->type, sha1);
 516        obj->idx.crc32 = input_crc32;
 517        return data;
 518}
 519
 520static void *unpack_data(struct object_entry *obj,
 521                         int (*consume)(const unsigned char *, unsigned long, void *),
 522                         void *cb_data)
 523{
 524        off_t from = obj[0].idx.offset + obj[0].hdr_size;
 525        unsigned long len = obj[1].idx.offset - from;
 526        unsigned char *data, *inbuf;
 527        git_zstream stream;
 528        int status;
 529
 530        data = xmalloc(consume ? 64*1024 : obj->size);
 531        inbuf = xmalloc((len < 64*1024) ? len : 64*1024);
 532
 533        memset(&stream, 0, sizeof(stream));
 534        git_inflate_init(&stream);
 535        stream.next_out = data;
 536        stream.avail_out = consume ? 64*1024 : obj->size;
 537
 538        do {
 539                ssize_t n = (len < 64*1024) ? len : 64*1024;
 540                n = pread(pack_fd, inbuf, n, from);
 541                if (n < 0)
 542                        die_errno(_("cannot pread pack file"));
 543                if (!n)
 544                        die(Q_("premature end of pack file, %lu byte missing",
 545                               "premature end of pack file, %lu bytes missing",
 546                               len),
 547                            len);
 548                from += n;
 549                len -= n;
 550                stream.next_in = inbuf;
 551                stream.avail_in = n;
 552                if (!consume)
 553                        status = git_inflate(&stream, 0);
 554                else {
 555                        do {
 556                                status = git_inflate(&stream, 0);
 557                                if (consume(data, stream.next_out - data, cb_data)) {
 558                                        free(inbuf);
 559                                        free(data);
 560                                        return NULL;
 561                                }
 562                                stream.next_out = data;
 563                                stream.avail_out = 64*1024;
 564                        } while (status == Z_OK && stream.avail_in);
 565                }
 566        } while (len && status == Z_OK && !stream.avail_in);
 567
 568        /* This has been inflated OK when first encountered, so... */
 569        if (status != Z_STREAM_END || stream.total_out != obj->size)
 570                die(_("serious inflate inconsistency"));
 571
 572        git_inflate_end(&stream);
 573        free(inbuf);
 574        if (consume) {
 575                free(data);
 576                data = NULL;
 577        }
 578        return data;
 579}
 580
 581static void *get_data_from_pack(struct object_entry *obj)
 582{
 583        return unpack_data(obj, NULL, NULL);
 584}
 585
 586static int compare_delta_bases(const union delta_base *base1,
 587                               const union delta_base *base2,
 588                               enum object_type type1,
 589                               enum object_type type2)
 590{
 591        int cmp = type1 - type2;
 592        if (cmp)
 593                return cmp;
 594        return memcmp(base1, base2, UNION_BASE_SZ);
 595}
 596
 597static int find_delta(const union delta_base *base, enum object_type type)
 598{
 599        int first = 0, last = nr_deltas;
 600
 601        while (first < last) {
 602                int next = (first + last) / 2;
 603                struct delta_entry *delta = &deltas[next];
 604                int cmp;
 605
 606                cmp = compare_delta_bases(base, &delta->base,
 607                                          type, objects[delta->obj_no].type);
 608                if (!cmp)
 609                        return next;
 610                if (cmp < 0) {
 611                        last = next;
 612                        continue;
 613                }
 614                first = next+1;
 615        }
 616        return -first-1;
 617}
 618
 619static void find_delta_children(const union delta_base *base,
 620                                int *first_index, int *last_index,
 621                                enum object_type type)
 622{
 623        int first = find_delta(base, type);
 624        int last = first;
 625        int end = nr_deltas - 1;
 626
 627        if (first < 0) {
 628                *first_index = 0;
 629                *last_index = -1;
 630                return;
 631        }
 632        while (first > 0 && !memcmp(&deltas[first - 1].base, base, UNION_BASE_SZ))
 633                --first;
 634        while (last < end && !memcmp(&deltas[last + 1].base, base, UNION_BASE_SZ))
 635                ++last;
 636        *first_index = first;
 637        *last_index = last;
 638}
 639
 640struct compare_data {
 641        struct object_entry *entry;
 642        struct git_istream *st;
 643        unsigned char *buf;
 644        unsigned long buf_size;
 645};
 646
 647static int compare_objects(const unsigned char *buf, unsigned long size,
 648                           void *cb_data)
 649{
 650        struct compare_data *data = cb_data;
 651
 652        if (data->buf_size < size) {
 653                free(data->buf);
 654                data->buf = xmalloc(size);
 655                data->buf_size = size;
 656        }
 657
 658        while (size) {
 659                ssize_t len = read_istream(data->st, data->buf, size);
 660                if (len == 0)
 661                        die(_("SHA1 COLLISION FOUND WITH %s !"),
 662                            sha1_to_hex(data->entry->idx.sha1));
 663                if (len < 0)
 664                        die(_("unable to read %s"),
 665                            sha1_to_hex(data->entry->idx.sha1));
 666                if (memcmp(buf, data->buf, len))
 667                        die(_("SHA1 COLLISION FOUND WITH %s !"),
 668                            sha1_to_hex(data->entry->idx.sha1));
 669                size -= len;
 670                buf += len;
 671        }
 672        return 0;
 673}
 674
 675static int check_collison(struct object_entry *entry)
 676{
 677        struct compare_data data;
 678        enum object_type type;
 679        unsigned long size;
 680
 681        if (entry->size <= big_file_threshold || entry->type != OBJ_BLOB)
 682                return -1;
 683
 684        memset(&data, 0, sizeof(data));
 685        data.entry = entry;
 686        data.st = open_istream(entry->idx.sha1, &type, &size, NULL);
 687        if (!data.st)
 688                return -1;
 689        if (size != entry->size || type != entry->type)
 690                die(_("SHA1 COLLISION FOUND WITH %s !"),
 691                    sha1_to_hex(entry->idx.sha1));
 692        unpack_data(entry, compare_objects, &data);
 693        close_istream(data.st);
 694        free(data.buf);
 695        return 0;
 696}
 697
 698static void sha1_object(const void *data, struct object_entry *obj_entry,
 699                        unsigned long size, enum object_type type,
 700                        const unsigned char *sha1)
 701{
 702        void *new_data = NULL;
 703        int collision_test_needed;
 704
 705        assert(data || obj_entry);
 706
 707        read_lock();
 708        collision_test_needed = has_sha1_file(sha1);
 709        read_unlock();
 710
 711        if (collision_test_needed && !data) {
 712                read_lock();
 713                if (!check_collison(obj_entry))
 714                        collision_test_needed = 0;
 715                read_unlock();
 716        }
 717        if (collision_test_needed) {
 718                void *has_data;
 719                enum object_type has_type;
 720                unsigned long has_size;
 721                read_lock();
 722                has_type = sha1_object_info(sha1, &has_size);
 723                if (has_type != type || has_size != size)
 724                        die(_("SHA1 COLLISION FOUND WITH %s !"), sha1_to_hex(sha1));
 725                has_data = read_sha1_file(sha1, &has_type, &has_size);
 726                read_unlock();
 727                if (!data)
 728                        data = new_data = get_data_from_pack(obj_entry);
 729                if (!has_data)
 730                        die(_("cannot read existing object %s"), sha1_to_hex(sha1));
 731                if (size != has_size || type != has_type ||
 732                    memcmp(data, has_data, size) != 0)
 733                        die(_("SHA1 COLLISION FOUND WITH %s !"), sha1_to_hex(sha1));
 734                free(has_data);
 735        }
 736
 737        if (strict) {
 738                read_lock();
 739                if (type == OBJ_BLOB) {
 740                        struct blob *blob = lookup_blob(sha1);
 741                        if (blob)
 742                                blob->object.flags |= FLAG_CHECKED;
 743                        else
 744                                die(_("invalid blob object %s"), sha1_to_hex(sha1));
 745                } else {
 746                        struct object *obj;
 747                        int eaten;
 748                        void *buf = (void *) data;
 749
 750                        if (!buf)
 751                                buf = new_data = get_data_from_pack(obj_entry);
 752
 753                        /*
 754                         * we do not need to free the memory here, as the
 755                         * buf is deleted by the caller.
 756                         */
 757                        obj = parse_object_buffer(sha1, type, size, buf, &eaten);
 758                        if (!obj)
 759                                die(_("invalid %s"), typename(type));
 760                        if (fsck_object(obj, 1, fsck_error_function))
 761                                die(_("Error in object"));
 762                        if (fsck_walk(obj, mark_link, NULL))
 763                                die(_("Not all child objects of %s are reachable"), sha1_to_hex(obj->sha1));
 764
 765                        if (obj->type == OBJ_TREE) {
 766                                struct tree *item = (struct tree *) obj;
 767                                item->buffer = NULL;
 768                        }
 769                        if (obj->type == OBJ_COMMIT) {
 770                                struct commit *commit = (struct commit *) obj;
 771                                commit->buffer = NULL;
 772                        }
 773                        obj->flags |= FLAG_CHECKED;
 774                }
 775                read_unlock();
 776        }
 777
 778        free(new_data);
 779}
 780
 781/*
 782 * This function is part of find_unresolved_deltas(). There are two
 783 * walkers going in the opposite ways.
 784 *
 785 * The first one in find_unresolved_deltas() traverses down from
 786 * parent node to children, deflating nodes along the way. However,
 787 * memory for deflated nodes is limited by delta_base_cache_limit, so
 788 * at some point parent node's deflated content may be freed.
 789 *
 790 * The second walker is this function, which goes from current node up
 791 * to top parent if necessary to deflate the node. In normal
 792 * situation, its parent node would be already deflated, so it just
 793 * needs to apply delta.
 794 *
 795 * In the worst case scenario, parent node is no longer deflated because
 796 * we're running out of delta_base_cache_limit; we need to re-deflate
 797 * parents, possibly up to the top base.
 798 *
 799 * All deflated objects here are subject to be freed if we exceed
 800 * delta_base_cache_limit, just like in find_unresolved_deltas(), we
 801 * just need to make sure the last node is not freed.
 802 */
 803static void *get_base_data(struct base_data *c)
 804{
 805        if (!c->data) {
 806                struct object_entry *obj = c->obj;
 807                struct base_data **delta = NULL;
 808                int delta_nr = 0, delta_alloc = 0;
 809
 810                while (is_delta_type(c->obj->type) && !c->data) {
 811                        ALLOC_GROW(delta, delta_nr + 1, delta_alloc);
 812                        delta[delta_nr++] = c;
 813                        c = c->base;
 814                }
 815                if (!delta_nr) {
 816                        c->data = get_data_from_pack(obj);
 817                        c->size = obj->size;
 818                        get_thread_data()->base_cache_used += c->size;
 819                        prune_base_data(c);
 820                }
 821                for (; delta_nr > 0; delta_nr--) {
 822                        void *base, *raw;
 823                        c = delta[delta_nr - 1];
 824                        obj = c->obj;
 825                        base = get_base_data(c->base);
 826                        raw = get_data_from_pack(obj);
 827                        c->data = patch_delta(
 828                                base, c->base->size,
 829                                raw, obj->size,
 830                                &c->size);
 831                        free(raw);
 832                        if (!c->data)
 833                                bad_object(obj->idx.offset, _("failed to apply delta"));
 834                        get_thread_data()->base_cache_used += c->size;
 835                        prune_base_data(c);
 836                }
 837                free(delta);
 838        }
 839        return c->data;
 840}
 841
 842static void resolve_delta(struct object_entry *delta_obj,
 843                          struct base_data *base, struct base_data *result)
 844{
 845        void *base_data, *delta_data;
 846
 847        delta_obj->real_type = base->obj->real_type;
 848        if (show_stat) {
 849                delta_obj->delta_depth = base->obj->delta_depth + 1;
 850                deepest_delta_lock();
 851                if (deepest_delta < delta_obj->delta_depth)
 852                        deepest_delta = delta_obj->delta_depth;
 853                deepest_delta_unlock();
 854        }
 855        delta_obj->base_object_no = base->obj - objects;
 856        delta_data = get_data_from_pack(delta_obj);
 857        base_data = get_base_data(base);
 858        result->obj = delta_obj;
 859        result->data = patch_delta(base_data, base->size,
 860                                   delta_data, delta_obj->size, &result->size);
 861        free(delta_data);
 862        if (!result->data)
 863                bad_object(delta_obj->idx.offset, _("failed to apply delta"));
 864        hash_sha1_file(result->data, result->size,
 865                       typename(delta_obj->real_type), delta_obj->idx.sha1);
 866        sha1_object(result->data, NULL, result->size, delta_obj->real_type,
 867                    delta_obj->idx.sha1);
 868        counter_lock();
 869        nr_resolved_deltas++;
 870        counter_unlock();
 871}
 872
 873static struct base_data *find_unresolved_deltas_1(struct base_data *base,
 874                                                  struct base_data *prev_base)
 875{
 876        if (base->ref_last == -1 && base->ofs_last == -1) {
 877                union delta_base base_spec;
 878
 879                hashcpy(base_spec.sha1, base->obj->idx.sha1);
 880                find_delta_children(&base_spec,
 881                                    &base->ref_first, &base->ref_last, OBJ_REF_DELTA);
 882
 883                memset(&base_spec, 0, sizeof(base_spec));
 884                base_spec.offset = base->obj->idx.offset;
 885                find_delta_children(&base_spec,
 886                                    &base->ofs_first, &base->ofs_last, OBJ_OFS_DELTA);
 887
 888                if (base->ref_last == -1 && base->ofs_last == -1) {
 889                        free(base->data);
 890                        return NULL;
 891                }
 892
 893                link_base_data(prev_base, base);
 894        }
 895
 896        if (base->ref_first <= base->ref_last) {
 897                struct object_entry *child = objects + deltas[base->ref_first].obj_no;
 898                struct base_data *result = alloc_base_data();
 899
 900                assert(child->real_type == OBJ_REF_DELTA);
 901                resolve_delta(child, base, result);
 902                if (base->ref_first == base->ref_last && base->ofs_last == -1)
 903                        free_base_data(base);
 904
 905                base->ref_first++;
 906                return result;
 907        }
 908
 909        if (base->ofs_first <= base->ofs_last) {
 910                struct object_entry *child = objects + deltas[base->ofs_first].obj_no;
 911                struct base_data *result = alloc_base_data();
 912
 913                assert(child->real_type == OBJ_OFS_DELTA);
 914                resolve_delta(child, base, result);
 915                if (base->ofs_first == base->ofs_last)
 916                        free_base_data(base);
 917
 918                base->ofs_first++;
 919                return result;
 920        }
 921
 922        unlink_base_data(base);
 923        return NULL;
 924}
 925
 926static void find_unresolved_deltas(struct base_data *base)
 927{
 928        struct base_data *new_base, *prev_base = NULL;
 929        for (;;) {
 930                new_base = find_unresolved_deltas_1(base, prev_base);
 931
 932                if (new_base) {
 933                        prev_base = base;
 934                        base = new_base;
 935                } else {
 936                        free(base);
 937                        base = prev_base;
 938                        if (!base)
 939                                return;
 940                        prev_base = base->base;
 941                }
 942        }
 943}
 944
 945static int compare_delta_entry(const void *a, const void *b)
 946{
 947        const struct delta_entry *delta_a = a;
 948        const struct delta_entry *delta_b = b;
 949
 950        /* group by type (ref vs ofs) and then by value (sha-1 or offset) */
 951        return compare_delta_bases(&delta_a->base, &delta_b->base,
 952                                   objects[delta_a->obj_no].type,
 953                                   objects[delta_b->obj_no].type);
 954}
 955
 956static void resolve_base(struct object_entry *obj)
 957{
 958        struct base_data *base_obj = alloc_base_data();
 959        base_obj->obj = obj;
 960        base_obj->data = NULL;
 961        find_unresolved_deltas(base_obj);
 962}
 963
 964#ifndef NO_PTHREADS
 965static void *threaded_second_pass(void *data)
 966{
 967        set_thread_data(data);
 968        for (;;) {
 969                int i;
 970                counter_lock();
 971                display_progress(progress, nr_resolved_deltas);
 972                counter_unlock();
 973                work_lock();
 974                while (nr_dispatched < nr_objects &&
 975                       is_delta_type(objects[nr_dispatched].type))
 976                        nr_dispatched++;
 977                if (nr_dispatched >= nr_objects) {
 978                        work_unlock();
 979                        break;
 980                }
 981                i = nr_dispatched++;
 982                work_unlock();
 983
 984                resolve_base(&objects[i]);
 985        }
 986        return NULL;
 987}
 988#endif
 989
 990/*
 991 * First pass:
 992 * - find locations of all objects;
 993 * - calculate SHA1 of all non-delta objects;
 994 * - remember base (SHA1 or offset) for all deltas.
 995 */
 996static void parse_pack_objects(unsigned char *sha1)
 997{
 998        int i, nr_delays = 0;
 999        struct delta_entry *delta = deltas;
1000        struct stat st;
1001
1002        if (verbose)
1003                progress = start_progress(
1004                                from_stdin ? _("Receiving objects") : _("Indexing objects"),
1005                                nr_objects);
1006        for (i = 0; i < nr_objects; i++) {
1007                struct object_entry *obj = &objects[i];
1008                void *data = unpack_raw_entry(obj, &delta->base, obj->idx.sha1);
1009                obj->real_type = obj->type;
1010                if (is_delta_type(obj->type)) {
1011                        nr_deltas++;
1012                        delta->obj_no = i;
1013                        delta++;
1014                } else if (!data) {
1015                        /* large blobs, check later */
1016                        obj->real_type = OBJ_BAD;
1017                        nr_delays++;
1018                } else
1019                        sha1_object(data, NULL, obj->size, obj->type, obj->idx.sha1);
1020                free(data);
1021                display_progress(progress, i+1);
1022        }
1023        objects[i].idx.offset = consumed_bytes;
1024        stop_progress(&progress);
1025
1026        /* Check pack integrity */
1027        flush();
1028        git_SHA1_Final(sha1, &input_ctx);
1029        if (hashcmp(fill(20), sha1))
1030                die(_("pack is corrupted (SHA1 mismatch)"));
1031        use(20);
1032
1033        /* If input_fd is a file, we should have reached its end now. */
1034        if (fstat(input_fd, &st))
1035                die_errno(_("cannot fstat packfile"));
1036        if (S_ISREG(st.st_mode) &&
1037                        lseek(input_fd, 0, SEEK_CUR) - input_len != st.st_size)
1038                die(_("pack has junk at the end"));
1039
1040        for (i = 0; i < nr_objects; i++) {
1041                struct object_entry *obj = &objects[i];
1042                if (obj->real_type != OBJ_BAD)
1043                        continue;
1044                obj->real_type = obj->type;
1045                sha1_object(NULL, obj, obj->size, obj->type, obj->idx.sha1);
1046                nr_delays--;
1047        }
1048        if (nr_delays)
1049                die(_("confusion beyond insanity in parse_pack_objects()"));
1050}
1051
1052/*
1053 * Second pass:
1054 * - for all non-delta objects, look if it is used as a base for
1055 *   deltas;
1056 * - if used as a base, uncompress the object and apply all deltas,
1057 *   recursively checking if the resulting object is used as a base
1058 *   for some more deltas.
1059 */
1060static void resolve_deltas(void)
1061{
1062        int i;
1063
1064        if (!nr_deltas)
1065                return;
1066
1067        /* Sort deltas by base SHA1/offset for fast searching */
1068        qsort(deltas, nr_deltas, sizeof(struct delta_entry),
1069              compare_delta_entry);
1070
1071        if (verbose)
1072                progress = start_progress(_("Resolving deltas"), nr_deltas);
1073
1074#ifndef NO_PTHREADS
1075        nr_dispatched = 0;
1076        if (nr_threads > 1 || getenv("GIT_FORCE_THREADS")) {
1077                init_thread();
1078                for (i = 0; i < nr_threads; i++) {
1079                        int ret = pthread_create(&thread_data[i].thread, NULL,
1080                                                 threaded_second_pass, thread_data + i);
1081                        if (ret)
1082                                die(_("unable to create thread: %s"),
1083                                    strerror(ret));
1084                }
1085                for (i = 0; i < nr_threads; i++)
1086                        pthread_join(thread_data[i].thread, NULL);
1087                cleanup_thread();
1088                return;
1089        }
1090#endif
1091
1092        for (i = 0; i < nr_objects; i++) {
1093                struct object_entry *obj = &objects[i];
1094
1095                if (is_delta_type(obj->type))
1096                        continue;
1097                resolve_base(obj);
1098                display_progress(progress, nr_resolved_deltas);
1099        }
1100}
1101
1102/*
1103 * Third pass:
1104 * - append objects to convert thin pack to full pack if required
1105 * - write the final 20-byte SHA-1
1106 */
1107static void fix_unresolved_deltas(struct sha1file *f, int nr_unresolved);
1108static void conclude_pack(int fix_thin_pack, const char *curr_pack, unsigned char *pack_sha1)
1109{
1110        if (nr_deltas == nr_resolved_deltas) {
1111                stop_progress(&progress);
1112                /* Flush remaining pack final 20-byte SHA1. */
1113                flush();
1114                return;
1115        }
1116
1117        if (fix_thin_pack) {
1118                struct sha1file *f;
1119                unsigned char read_sha1[20], tail_sha1[20];
1120                struct strbuf msg = STRBUF_INIT;
1121                int nr_unresolved = nr_deltas - nr_resolved_deltas;
1122                int nr_objects_initial = nr_objects;
1123                if (nr_unresolved <= 0)
1124                        die(_("confusion beyond insanity"));
1125                objects = xrealloc(objects,
1126                                   (nr_objects + nr_unresolved + 1)
1127                                   * sizeof(*objects));
1128                memset(objects + nr_objects + 1, 0,
1129                       nr_unresolved * sizeof(*objects));
1130                f = sha1fd(output_fd, curr_pack);
1131                fix_unresolved_deltas(f, nr_unresolved);
1132                strbuf_addf(&msg, _("completed with %d local objects"),
1133                            nr_objects - nr_objects_initial);
1134                stop_progress_msg(&progress, msg.buf);
1135                strbuf_release(&msg);
1136                sha1close(f, tail_sha1, 0);
1137                hashcpy(read_sha1, pack_sha1);
1138                fixup_pack_header_footer(output_fd, pack_sha1,
1139                                         curr_pack, nr_objects,
1140                                         read_sha1, consumed_bytes-20);
1141                if (hashcmp(read_sha1, tail_sha1) != 0)
1142                        die(_("Unexpected tail checksum for %s "
1143                              "(disk corruption?)"), curr_pack);
1144        }
1145        if (nr_deltas != nr_resolved_deltas)
1146                die(Q_("pack has %d unresolved delta",
1147                       "pack has %d unresolved deltas",
1148                       nr_deltas - nr_resolved_deltas),
1149                    nr_deltas - nr_resolved_deltas);
1150}
1151
1152static int write_compressed(struct sha1file *f, void *in, unsigned int size)
1153{
1154        git_zstream stream;
1155        int status;
1156        unsigned char outbuf[4096];
1157
1158        memset(&stream, 0, sizeof(stream));
1159        git_deflate_init(&stream, zlib_compression_level);
1160        stream.next_in = in;
1161        stream.avail_in = size;
1162
1163        do {
1164                stream.next_out = outbuf;
1165                stream.avail_out = sizeof(outbuf);
1166                status = git_deflate(&stream, Z_FINISH);
1167                sha1write(f, outbuf, sizeof(outbuf) - stream.avail_out);
1168        } while (status == Z_OK);
1169
1170        if (status != Z_STREAM_END)
1171                die(_("unable to deflate appended object (%d)"), status);
1172        size = stream.total_out;
1173        git_deflate_end(&stream);
1174        return size;
1175}
1176
1177static struct object_entry *append_obj_to_pack(struct sha1file *f,
1178                               const unsigned char *sha1, void *buf,
1179                               unsigned long size, enum object_type type)
1180{
1181        struct object_entry *obj = &objects[nr_objects++];
1182        unsigned char header[10];
1183        unsigned long s = size;
1184        int n = 0;
1185        unsigned char c = (type << 4) | (s & 15);
1186        s >>= 4;
1187        while (s) {
1188                header[n++] = c | 0x80;
1189                c = s & 0x7f;
1190                s >>= 7;
1191        }
1192        header[n++] = c;
1193        crc32_begin(f);
1194        sha1write(f, header, n);
1195        obj[0].size = size;
1196        obj[0].hdr_size = n;
1197        obj[0].type = type;
1198        obj[0].real_type = type;
1199        obj[1].idx.offset = obj[0].idx.offset + n;
1200        obj[1].idx.offset += write_compressed(f, buf, size);
1201        obj[0].idx.crc32 = crc32_end(f);
1202        sha1flush(f);
1203        hashcpy(obj->idx.sha1, sha1);
1204        return obj;
1205}
1206
1207static int delta_pos_compare(const void *_a, const void *_b)
1208{
1209        struct delta_entry *a = *(struct delta_entry **)_a;
1210        struct delta_entry *b = *(struct delta_entry **)_b;
1211        return a->obj_no - b->obj_no;
1212}
1213
1214static void fix_unresolved_deltas(struct sha1file *f, int nr_unresolved)
1215{
1216        struct delta_entry **sorted_by_pos;
1217        int i, n = 0;
1218
1219        /*
1220         * Since many unresolved deltas may well be themselves base objects
1221         * for more unresolved deltas, we really want to include the
1222         * smallest number of base objects that would cover as much delta
1223         * as possible by picking the
1224         * trunc deltas first, allowing for other deltas to resolve without
1225         * additional base objects.  Since most base objects are to be found
1226         * before deltas depending on them, a good heuristic is to start
1227         * resolving deltas in the same order as their position in the pack.
1228         */
1229        sorted_by_pos = xmalloc(nr_unresolved * sizeof(*sorted_by_pos));
1230        for (i = 0; i < nr_deltas; i++) {
1231                if (objects[deltas[i].obj_no].real_type != OBJ_REF_DELTA)
1232                        continue;
1233                sorted_by_pos[n++] = &deltas[i];
1234        }
1235        qsort(sorted_by_pos, n, sizeof(*sorted_by_pos), delta_pos_compare);
1236
1237        for (i = 0; i < n; i++) {
1238                struct delta_entry *d = sorted_by_pos[i];
1239                enum object_type type;
1240                struct base_data *base_obj = alloc_base_data();
1241
1242                if (objects[d->obj_no].real_type != OBJ_REF_DELTA)
1243                        continue;
1244                base_obj->data = read_sha1_file(d->base.sha1, &type, &base_obj->size);
1245                if (!base_obj->data)
1246                        continue;
1247
1248                if (check_sha1_signature(d->base.sha1, base_obj->data,
1249                                base_obj->size, typename(type)))
1250                        die(_("local object %s is corrupt"), sha1_to_hex(d->base.sha1));
1251                base_obj->obj = append_obj_to_pack(f, d->base.sha1,
1252                                        base_obj->data, base_obj->size, type);
1253                find_unresolved_deltas(base_obj);
1254                display_progress(progress, nr_resolved_deltas);
1255        }
1256        free(sorted_by_pos);
1257}
1258
1259static void final(const char *final_pack_name, const char *curr_pack_name,
1260                  const char *final_index_name, const char *curr_index_name,
1261                  const char *keep_name, const char *keep_msg,
1262                  unsigned char *sha1)
1263{
1264        const char *report = "pack";
1265        char name[PATH_MAX];
1266        int err;
1267
1268        if (!from_stdin) {
1269                close(input_fd);
1270        } else {
1271                fsync_or_die(output_fd, curr_pack_name);
1272                err = close(output_fd);
1273                if (err)
1274                        die_errno(_("error while closing pack file"));
1275        }
1276
1277        if (keep_msg) {
1278                int keep_fd, keep_msg_len = strlen(keep_msg);
1279
1280                if (!keep_name)
1281                        keep_fd = odb_pack_keep(name, sizeof(name), sha1);
1282                else
1283                        keep_fd = open(keep_name, O_RDWR|O_CREAT|O_EXCL, 0600);
1284
1285                if (keep_fd < 0) {
1286                        if (errno != EEXIST)
1287                                die_errno(_("cannot write keep file '%s'"),
1288                                          keep_name);
1289                } else {
1290                        if (keep_msg_len > 0) {
1291                                write_or_die(keep_fd, keep_msg, keep_msg_len);
1292                                write_or_die(keep_fd, "\n", 1);
1293                        }
1294                        if (close(keep_fd) != 0)
1295                                die_errno(_("cannot close written keep file '%s'"),
1296                                    keep_name);
1297                        report = "keep";
1298                }
1299        }
1300
1301        if (final_pack_name != curr_pack_name) {
1302                if (!final_pack_name) {
1303                        snprintf(name, sizeof(name), "%s/pack/pack-%s.pack",
1304                                 get_object_directory(), sha1_to_hex(sha1));
1305                        final_pack_name = name;
1306                }
1307                if (move_temp_to_file(curr_pack_name, final_pack_name))
1308                        die(_("cannot store pack file"));
1309        } else if (from_stdin)
1310                chmod(final_pack_name, 0444);
1311
1312        if (final_index_name != curr_index_name) {
1313                if (!final_index_name) {
1314                        snprintf(name, sizeof(name), "%s/pack/pack-%s.idx",
1315                                 get_object_directory(), sha1_to_hex(sha1));
1316                        final_index_name = name;
1317                }
1318                if (move_temp_to_file(curr_index_name, final_index_name))
1319                        die(_("cannot store index file"));
1320        } else
1321                chmod(final_index_name, 0444);
1322
1323        if (!from_stdin) {
1324                printf("%s\n", sha1_to_hex(sha1));
1325        } else {
1326                char buf[48];
1327                int len = snprintf(buf, sizeof(buf), "%s\t%s\n",
1328                                   report, sha1_to_hex(sha1));
1329                write_or_die(1, buf, len);
1330
1331                /*
1332                 * Let's just mimic git-unpack-objects here and write
1333                 * the last part of the input buffer to stdout.
1334                 */
1335                while (input_len) {
1336                        err = xwrite(1, input_buffer + input_offset, input_len);
1337                        if (err <= 0)
1338                                break;
1339                        input_len -= err;
1340                        input_offset += err;
1341                }
1342        }
1343}
1344
1345static int git_index_pack_config(const char *k, const char *v, void *cb)
1346{
1347        struct pack_idx_option *opts = cb;
1348
1349        if (!strcmp(k, "pack.indexversion")) {
1350                opts->version = git_config_int(k, v);
1351                if (opts->version > 2)
1352                        die(_("bad pack.indexversion=%"PRIu32), opts->version);
1353                return 0;
1354        }
1355        if (!strcmp(k, "pack.threads")) {
1356                nr_threads = git_config_int(k, v);
1357                if (nr_threads < 0)
1358                        die(_("invalid number of threads specified (%d)"),
1359                            nr_threads);
1360#ifdef NO_PTHREADS
1361                if (nr_threads != 1)
1362                        warning(_("no threads support, ignoring %s"), k);
1363                nr_threads = 1;
1364#endif
1365                return 0;
1366        }
1367        return git_default_config(k, v, cb);
1368}
1369
1370static int cmp_uint32(const void *a_, const void *b_)
1371{
1372        uint32_t a = *((uint32_t *)a_);
1373        uint32_t b = *((uint32_t *)b_);
1374
1375        return (a < b) ? -1 : (a != b);
1376}
1377
1378static void read_v2_anomalous_offsets(struct packed_git *p,
1379                                      struct pack_idx_option *opts)
1380{
1381        const uint32_t *idx1, *idx2;
1382        uint32_t i;
1383
1384        /* The address of the 4-byte offset table */
1385        idx1 = (((const uint32_t *)p->index_data)
1386                + 2 /* 8-byte header */
1387                + 256 /* fan out */
1388                + 5 * p->num_objects /* 20-byte SHA-1 table */
1389                + p->num_objects /* CRC32 table */
1390                );
1391
1392        /* The address of the 8-byte offset table */
1393        idx2 = idx1 + p->num_objects;
1394
1395        for (i = 0; i < p->num_objects; i++) {
1396                uint32_t off = ntohl(idx1[i]);
1397                if (!(off & 0x80000000))
1398                        continue;
1399                off = off & 0x7fffffff;
1400                if (idx2[off * 2])
1401                        continue;
1402                /*
1403                 * The real offset is ntohl(idx2[off * 2]) in high 4
1404                 * octets, and ntohl(idx2[off * 2 + 1]) in low 4
1405                 * octets.  But idx2[off * 2] is Zero!!!
1406                 */
1407                ALLOC_GROW(opts->anomaly, opts->anomaly_nr + 1, opts->anomaly_alloc);
1408                opts->anomaly[opts->anomaly_nr++] = ntohl(idx2[off * 2 + 1]);
1409        }
1410
1411        if (1 < opts->anomaly_nr)
1412                qsort(opts->anomaly, opts->anomaly_nr, sizeof(uint32_t), cmp_uint32);
1413}
1414
1415static void read_idx_option(struct pack_idx_option *opts, const char *pack_name)
1416{
1417        struct packed_git *p = add_packed_git(pack_name, strlen(pack_name), 1);
1418
1419        if (!p)
1420                die(_("Cannot open existing pack file '%s'"), pack_name);
1421        if (open_pack_index(p))
1422                die(_("Cannot open existing pack idx file for '%s'"), pack_name);
1423
1424        /* Read the attributes from the existing idx file */
1425        opts->version = p->index_version;
1426
1427        if (opts->version == 2)
1428                read_v2_anomalous_offsets(p, opts);
1429
1430        /*
1431         * Get rid of the idx file as we do not need it anymore.
1432         * NEEDSWORK: extract this bit from free_pack_by_name() in
1433         * sha1_file.c, perhaps?  It shouldn't matter very much as we
1434         * know we haven't installed this pack (hence we never have
1435         * read anything from it).
1436         */
1437        close_pack_index(p);
1438        free(p);
1439}
1440
1441static void show_pack_info(int stat_only)
1442{
1443        int i, baseobjects = nr_objects - nr_deltas;
1444        unsigned long *chain_histogram = NULL;
1445
1446        if (deepest_delta)
1447                chain_histogram = xcalloc(deepest_delta, sizeof(unsigned long));
1448
1449        for (i = 0; i < nr_objects; i++) {
1450                struct object_entry *obj = &objects[i];
1451
1452                if (is_delta_type(obj->type))
1453                        chain_histogram[obj->delta_depth - 1]++;
1454                if (stat_only)
1455                        continue;
1456                printf("%s %-6s %lu %lu %"PRIuMAX,
1457                       sha1_to_hex(obj->idx.sha1),
1458                       typename(obj->real_type), obj->size,
1459                       (unsigned long)(obj[1].idx.offset - obj->idx.offset),
1460                       (uintmax_t)obj->idx.offset);
1461                if (is_delta_type(obj->type)) {
1462                        struct object_entry *bobj = &objects[obj->base_object_no];
1463                        printf(" %u %s", obj->delta_depth, sha1_to_hex(bobj->idx.sha1));
1464                }
1465                putchar('\n');
1466        }
1467
1468        if (baseobjects)
1469                printf_ln(Q_("non delta: %d object",
1470                             "non delta: %d objects",
1471                             baseobjects),
1472                          baseobjects);
1473        for (i = 0; i < deepest_delta; i++) {
1474                if (!chain_histogram[i])
1475                        continue;
1476                printf_ln(Q_("chain length = %d: %lu object",
1477                             "chain length = %d: %lu objects",
1478                             chain_histogram[i]),
1479                          i + 1,
1480                          chain_histogram[i]);
1481        }
1482}
1483
1484int cmd_index_pack(int argc, const char **argv, const char *prefix)
1485{
1486        int i, fix_thin_pack = 0, verify = 0, stat_only = 0;
1487        const char *curr_pack, *curr_index;
1488        const char *index_name = NULL, *pack_name = NULL;
1489        const char *keep_name = NULL, *keep_msg = NULL;
1490        char *index_name_buf = NULL, *keep_name_buf = NULL;
1491        struct pack_idx_entry **idx_objects;
1492        struct pack_idx_option opts;
1493        unsigned char pack_sha1[20];
1494
1495        if (argc == 2 && !strcmp(argv[1], "-h"))
1496                usage(index_pack_usage);
1497
1498        read_replace_refs = 0;
1499
1500        reset_pack_idx_option(&opts);
1501        git_config(git_index_pack_config, &opts);
1502        if (prefix && chdir(prefix))
1503                die(_("Cannot come back to cwd"));
1504
1505        for (i = 1; i < argc; i++) {
1506                const char *arg = argv[i];
1507
1508                if (*arg == '-') {
1509                        if (!strcmp(arg, "--stdin")) {
1510                                from_stdin = 1;
1511                        } else if (!strcmp(arg, "--fix-thin")) {
1512                                fix_thin_pack = 1;
1513                        } else if (!strcmp(arg, "--strict")) {
1514                                strict = 1;
1515                        } else if (!strcmp(arg, "--verify")) {
1516                                verify = 1;
1517                        } else if (!strcmp(arg, "--verify-stat")) {
1518                                verify = 1;
1519                                show_stat = 1;
1520                        } else if (!strcmp(arg, "--verify-stat-only")) {
1521                                verify = 1;
1522                                show_stat = 1;
1523                                stat_only = 1;
1524                        } else if (!strcmp(arg, "--keep")) {
1525                                keep_msg = "";
1526                        } else if (!prefixcmp(arg, "--keep=")) {
1527                                keep_msg = arg + 7;
1528                        } else if (!prefixcmp(arg, "--threads=")) {
1529                                char *end;
1530                                nr_threads = strtoul(arg+10, &end, 0);
1531                                if (!arg[10] || *end || nr_threads < 0)
1532                                        usage(index_pack_usage);
1533#ifdef NO_PTHREADS
1534                                if (nr_threads != 1)
1535                                        warning(_("no threads support, "
1536                                                  "ignoring %s"), arg);
1537                                nr_threads = 1;
1538#endif
1539                        } else if (!prefixcmp(arg, "--pack_header=")) {
1540                                struct pack_header *hdr;
1541                                char *c;
1542
1543                                hdr = (struct pack_header *)input_buffer;
1544                                hdr->hdr_signature = htonl(PACK_SIGNATURE);
1545                                hdr->hdr_version = htonl(strtoul(arg + 14, &c, 10));
1546                                if (*c != ',')
1547                                        die(_("bad %s"), arg);
1548                                hdr->hdr_entries = htonl(strtoul(c + 1, &c, 10));
1549                                if (*c)
1550                                        die(_("bad %s"), arg);
1551                                input_len = sizeof(*hdr);
1552                        } else if (!strcmp(arg, "-v")) {
1553                                verbose = 1;
1554                        } else if (!strcmp(arg, "-o")) {
1555                                if (index_name || (i+1) >= argc)
1556                                        usage(index_pack_usage);
1557                                index_name = argv[++i];
1558                        } else if (!prefixcmp(arg, "--index-version=")) {
1559                                char *c;
1560                                opts.version = strtoul(arg + 16, &c, 10);
1561                                if (opts.version > 2)
1562                                        die(_("bad %s"), arg);
1563                                if (*c == ',')
1564                                        opts.off32_limit = strtoul(c+1, &c, 0);
1565                                if (*c || opts.off32_limit & 0x80000000)
1566                                        die(_("bad %s"), arg);
1567                        } else
1568                                usage(index_pack_usage);
1569                        continue;
1570                }
1571
1572                if (pack_name)
1573                        usage(index_pack_usage);
1574                pack_name = arg;
1575        }
1576
1577        if (!pack_name && !from_stdin)
1578                usage(index_pack_usage);
1579        if (fix_thin_pack && !from_stdin)
1580                die(_("--fix-thin cannot be used without --stdin"));
1581        if (!index_name && pack_name) {
1582                int len = strlen(pack_name);
1583                if (!has_extension(pack_name, ".pack"))
1584                        die(_("packfile name '%s' does not end with '.pack'"),
1585                            pack_name);
1586                index_name_buf = xmalloc(len);
1587                memcpy(index_name_buf, pack_name, len - 5);
1588                strcpy(index_name_buf + len - 5, ".idx");
1589                index_name = index_name_buf;
1590        }
1591        if (keep_msg && !keep_name && pack_name) {
1592                int len = strlen(pack_name);
1593                if (!has_extension(pack_name, ".pack"))
1594                        die(_("packfile name '%s' does not end with '.pack'"),
1595                            pack_name);
1596                keep_name_buf = xmalloc(len);
1597                memcpy(keep_name_buf, pack_name, len - 5);
1598                strcpy(keep_name_buf + len - 5, ".keep");
1599                keep_name = keep_name_buf;
1600        }
1601        if (verify) {
1602                if (!index_name)
1603                        die(_("--verify with no packfile name given"));
1604                read_idx_option(&opts, index_name);
1605                opts.flags |= WRITE_IDX_VERIFY | WRITE_IDX_STRICT;
1606        }
1607        if (strict)
1608                opts.flags |= WRITE_IDX_STRICT;
1609
1610#ifndef NO_PTHREADS
1611        if (!nr_threads) {
1612                nr_threads = online_cpus();
1613                /* An experiment showed that more threads does not mean faster */
1614                if (nr_threads > 3)
1615                        nr_threads = 3;
1616        }
1617#endif
1618
1619        curr_pack = open_pack_file(pack_name);
1620        parse_pack_header();
1621        objects = xcalloc(nr_objects + 1, sizeof(struct object_entry));
1622        deltas = xcalloc(nr_objects, sizeof(struct delta_entry));
1623        parse_pack_objects(pack_sha1);
1624        resolve_deltas();
1625        conclude_pack(fix_thin_pack, curr_pack, pack_sha1);
1626        free(deltas);
1627        if (strict)
1628                check_objects();
1629
1630        if (show_stat)
1631                show_pack_info(stat_only);
1632
1633        idx_objects = xmalloc((nr_objects) * sizeof(struct pack_idx_entry *));
1634        for (i = 0; i < nr_objects; i++)
1635                idx_objects[i] = &objects[i].idx;
1636        curr_index = write_idx_file(index_name, idx_objects, nr_objects, &opts, pack_sha1);
1637        free(idx_objects);
1638
1639        if (!verify)
1640                final(pack_name, curr_pack,
1641                      index_name, curr_index,
1642                      keep_name, keep_msg,
1643                      pack_sha1);
1644        else
1645                close(input_fd);
1646        free(objects);
1647        free(index_name_buf);
1648        free(keep_name_buf);
1649        if (pack_name == NULL)
1650                free((void *) curr_pack);
1651        if (index_name == NULL)
1652                free((void *) curr_index);
1653
1654        return 0;
1655}