builtin / index-pack.con commit Merge branch 'jk/branch-verbose-merged' (5500095)
   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
  43struct thread_local {
  44#ifndef NO_PTHREADS
  45        pthread_t thread;
  46#endif
  47        struct base_data *base_cache;
  48        size_t base_cache_used;
  49        int pack_fd;
  50};
  51
  52/*
  53 * Even if sizeof(union delta_base) == 24 on 64-bit archs, we really want
  54 * to memcmp() only the first 20 bytes.
  55 */
  56#define UNION_BASE_SZ   20
  57
  58#define FLAG_LINK (1u<<20)
  59#define FLAG_CHECKED (1u<<21)
  60
  61struct delta_entry {
  62        union delta_base base;
  63        int obj_no;
  64};
  65
  66static struct object_entry *objects;
  67static struct delta_entry *deltas;
  68static struct thread_local nothread_data;
  69static int nr_objects;
  70static int nr_deltas;
  71static int nr_resolved_deltas;
  72static int nr_threads;
  73
  74static int from_stdin;
  75static int strict;
  76static int do_fsck_object;
  77static int verbose;
  78static int show_stat;
  79static int check_self_contained_and_connected;
  80
  81static struct progress *progress;
  82
  83/* We always read in 4kB chunks. */
  84static unsigned char input_buffer[4096];
  85static unsigned int input_offset, input_len;
  86static off_t consumed_bytes;
  87static unsigned deepest_delta;
  88static git_SHA_CTX input_ctx;
  89static uint32_t input_crc32;
  90static int input_fd, output_fd;
  91static const char *curr_pack;
  92
  93#ifndef NO_PTHREADS
  94
  95static struct thread_local *thread_data;
  96static int nr_dispatched;
  97static int threads_active;
  98
  99static pthread_mutex_t read_mutex;
 100#define read_lock()             lock_mutex(&read_mutex)
 101#define read_unlock()           unlock_mutex(&read_mutex)
 102
 103static pthread_mutex_t counter_mutex;
 104#define counter_lock()          lock_mutex(&counter_mutex)
 105#define counter_unlock()        unlock_mutex(&counter_mutex)
 106
 107static pthread_mutex_t work_mutex;
 108#define work_lock()             lock_mutex(&work_mutex)
 109#define work_unlock()           unlock_mutex(&work_mutex)
 110
 111static pthread_mutex_t deepest_delta_mutex;
 112#define deepest_delta_lock()    lock_mutex(&deepest_delta_mutex)
 113#define deepest_delta_unlock()  unlock_mutex(&deepest_delta_mutex)
 114
 115static pthread_mutex_t type_cas_mutex;
 116#define type_cas_lock()         lock_mutex(&type_cas_mutex)
 117#define type_cas_unlock()       unlock_mutex(&type_cas_mutex)
 118
 119static pthread_key_t key;
 120
 121static inline void lock_mutex(pthread_mutex_t *mutex)
 122{
 123        if (threads_active)
 124                pthread_mutex_lock(mutex);
 125}
 126
 127static inline void unlock_mutex(pthread_mutex_t *mutex)
 128{
 129        if (threads_active)
 130                pthread_mutex_unlock(mutex);
 131}
 132
 133/*
 134 * Mutex and conditional variable can't be statically-initialized on Windows.
 135 */
 136static void init_thread(void)
 137{
 138        int i;
 139        init_recursive_mutex(&read_mutex);
 140        pthread_mutex_init(&counter_mutex, NULL);
 141        pthread_mutex_init(&work_mutex, NULL);
 142        pthread_mutex_init(&type_cas_mutex, NULL);
 143        if (show_stat)
 144                pthread_mutex_init(&deepest_delta_mutex, NULL);
 145        pthread_key_create(&key, NULL);
 146        thread_data = xcalloc(nr_threads, sizeof(*thread_data));
 147        for (i = 0; i < nr_threads; i++) {
 148                thread_data[i].pack_fd = open(curr_pack, O_RDONLY);
 149                if (thread_data[i].pack_fd == -1)
 150                        die_errno(_("unable to open %s"), curr_pack);
 151        }
 152
 153        threads_active = 1;
 154}
 155
 156static void cleanup_thread(void)
 157{
 158        int i;
 159        if (!threads_active)
 160                return;
 161        threads_active = 0;
 162        pthread_mutex_destroy(&read_mutex);
 163        pthread_mutex_destroy(&counter_mutex);
 164        pthread_mutex_destroy(&work_mutex);
 165        pthread_mutex_destroy(&type_cas_mutex);
 166        if (show_stat)
 167                pthread_mutex_destroy(&deepest_delta_mutex);
 168        for (i = 0; i < nr_threads; i++)
 169                close(thread_data[i].pack_fd);
 170        pthread_key_delete(key);
 171        free(thread_data);
 172}
 173
 174#else
 175
 176#define read_lock()
 177#define read_unlock()
 178
 179#define counter_lock()
 180#define counter_unlock()
 181
 182#define work_lock()
 183#define work_unlock()
 184
 185#define deepest_delta_lock()
 186#define deepest_delta_unlock()
 187
 188#endif
 189
 190
 191static int mark_link(struct object *obj, int type, void *data)
 192{
 193        if (!obj)
 194                return -1;
 195
 196        if (type != OBJ_ANY && obj->type != type)
 197                die(_("object type mismatch at %s"), sha1_to_hex(obj->sha1));
 198
 199        obj->flags |= FLAG_LINK;
 200        return 0;
 201}
 202
 203/* The content of each linked object must have been checked
 204   or it must be already present in the object database */
 205static unsigned check_object(struct object *obj)
 206{
 207        if (!obj)
 208                return 0;
 209
 210        if (!(obj->flags & FLAG_LINK))
 211                return 0;
 212
 213        if (!(obj->flags & FLAG_CHECKED)) {
 214                unsigned long size;
 215                int type = sha1_object_info(obj->sha1, &size);
 216                if (type <= 0)
 217                        die(_("did not receive expected object %s"),
 218                              sha1_to_hex(obj->sha1));
 219                if (type != obj->type)
 220                        die(_("object %s: expected type %s, found %s"),
 221                            sha1_to_hex(obj->sha1),
 222                            typename(obj->type), typename(type));
 223                obj->flags |= FLAG_CHECKED;
 224                return 1;
 225        }
 226
 227        return 0;
 228}
 229
 230static unsigned check_objects(void)
 231{
 232        unsigned i, max, foreign_nr = 0;
 233
 234        max = get_max_object_index();
 235        for (i = 0; i < max; i++)
 236                foreign_nr += check_object(get_indexed_object(i));
 237        return foreign_nr;
 238}
 239
 240
 241/* Discard current buffer used content. */
 242static void flush(void)
 243{
 244        if (input_offset) {
 245                if (output_fd >= 0)
 246                        write_or_die(output_fd, input_buffer, input_offset);
 247                git_SHA1_Update(&input_ctx, input_buffer, input_offset);
 248                memmove(input_buffer, input_buffer + input_offset, input_len);
 249                input_offset = 0;
 250        }
 251}
 252
 253/*
 254 * Make sure at least "min" bytes are available in the buffer, and
 255 * return the pointer to the buffer.
 256 */
 257static void *fill(int min)
 258{
 259        if (min <= input_len)
 260                return input_buffer + input_offset;
 261        if (min > sizeof(input_buffer))
 262                die(Q_("cannot fill %d byte",
 263                       "cannot fill %d bytes",
 264                       min),
 265                    min);
 266        flush();
 267        do {
 268                ssize_t ret = xread(input_fd, input_buffer + input_len,
 269                                sizeof(input_buffer) - input_len);
 270                if (ret <= 0) {
 271                        if (!ret)
 272                                die(_("early EOF"));
 273                        die_errno(_("read error on input"));
 274                }
 275                input_len += ret;
 276                if (from_stdin)
 277                        display_throughput(progress, consumed_bytes + input_len);
 278        } while (input_len < min);
 279        return input_buffer;
 280}
 281
 282static void use(int bytes)
 283{
 284        if (bytes > input_len)
 285                die(_("used more bytes than were available"));
 286        input_crc32 = crc32(input_crc32, input_buffer + input_offset, bytes);
 287        input_len -= bytes;
 288        input_offset += bytes;
 289
 290        /* make sure off_t is sufficiently large not to wrap */
 291        if (signed_add_overflows(consumed_bytes, bytes))
 292                die(_("pack too large for current definition of off_t"));
 293        consumed_bytes += bytes;
 294}
 295
 296static const char *open_pack_file(const char *pack_name)
 297{
 298        if (from_stdin) {
 299                input_fd = 0;
 300                if (!pack_name) {
 301                        static char tmp_file[PATH_MAX];
 302                        output_fd = odb_mkstemp(tmp_file, sizeof(tmp_file),
 303                                                "pack/tmp_pack_XXXXXX");
 304                        pack_name = xstrdup(tmp_file);
 305                } else
 306                        output_fd = open(pack_name, O_CREAT|O_EXCL|O_RDWR, 0600);
 307                if (output_fd < 0)
 308                        die_errno(_("unable to create '%s'"), pack_name);
 309                nothread_data.pack_fd = output_fd;
 310        } else {
 311                input_fd = open(pack_name, O_RDONLY);
 312                if (input_fd < 0)
 313                        die_errno(_("cannot open packfile '%s'"), pack_name);
 314                output_fd = -1;
 315                nothread_data.pack_fd = input_fd;
 316        }
 317        git_SHA1_Init(&input_ctx);
 318        return pack_name;
 319}
 320
 321static void parse_pack_header(void)
 322{
 323        struct pack_header *hdr = fill(sizeof(struct pack_header));
 324
 325        /* Header consistency check */
 326        if (hdr->hdr_signature != htonl(PACK_SIGNATURE))
 327                die(_("pack signature mismatch"));
 328        if (!pack_version_ok(hdr->hdr_version))
 329                die(_("pack version %"PRIu32" unsupported"),
 330                        ntohl(hdr->hdr_version));
 331
 332        nr_objects = ntohl(hdr->hdr_entries);
 333        use(sizeof(struct pack_header));
 334}
 335
 336static NORETURN void bad_object(unsigned long offset, const char *format,
 337                       ...) __attribute__((format (printf, 2, 3)));
 338
 339static NORETURN void bad_object(unsigned long offset, const char *format, ...)
 340{
 341        va_list params;
 342        char buf[1024];
 343
 344        va_start(params, format);
 345        vsnprintf(buf, sizeof(buf), format, params);
 346        va_end(params);
 347        die(_("pack has bad object at offset %lu: %s"), offset, buf);
 348}
 349
 350static inline struct thread_local *get_thread_data(void)
 351{
 352#ifndef NO_PTHREADS
 353        if (threads_active)
 354                return pthread_getspecific(key);
 355        assert(!threads_active &&
 356               "This should only be reached when all threads are gone");
 357#endif
 358        return &nothread_data;
 359}
 360
 361#ifndef NO_PTHREADS
 362static void set_thread_data(struct thread_local *data)
 363{
 364        if (threads_active)
 365                pthread_setspecific(key, data);
 366}
 367#endif
 368
 369static struct base_data *alloc_base_data(void)
 370{
 371        struct base_data *base = xcalloc(1, sizeof(struct base_data));
 372        base->ref_last = -1;
 373        base->ofs_last = -1;
 374        return base;
 375}
 376
 377static void free_base_data(struct base_data *c)
 378{
 379        if (c->data) {
 380                free(c->data);
 381                c->data = NULL;
 382                get_thread_data()->base_cache_used -= c->size;
 383        }
 384}
 385
 386static void prune_base_data(struct base_data *retain)
 387{
 388        struct base_data *b;
 389        struct thread_local *data = get_thread_data();
 390        for (b = data->base_cache;
 391             data->base_cache_used > delta_base_cache_limit && b;
 392             b = b->child) {
 393                if (b->data && b != retain)
 394                        free_base_data(b);
 395        }
 396}
 397
 398static void link_base_data(struct base_data *base, struct base_data *c)
 399{
 400        if (base)
 401                base->child = c;
 402        else
 403                get_thread_data()->base_cache = c;
 404
 405        c->base = base;
 406        c->child = NULL;
 407        if (c->data)
 408                get_thread_data()->base_cache_used += c->size;
 409        prune_base_data(c);
 410}
 411
 412static void unlink_base_data(struct base_data *c)
 413{
 414        struct base_data *base = c->base;
 415        if (base)
 416                base->child = NULL;
 417        else
 418                get_thread_data()->base_cache = NULL;
 419        free_base_data(c);
 420}
 421
 422static int is_delta_type(enum object_type type)
 423{
 424        return (type == OBJ_REF_DELTA || type == OBJ_OFS_DELTA);
 425}
 426
 427static void *unpack_entry_data(unsigned long offset, unsigned long size,
 428                               enum object_type type, unsigned char *sha1)
 429{
 430        static char fixed_buf[8192];
 431        int status;
 432        git_zstream stream;
 433        void *buf;
 434        git_SHA_CTX c;
 435        char hdr[32];
 436        int hdrlen;
 437
 438        if (!is_delta_type(type)) {
 439                hdrlen = sprintf(hdr, "%s %lu", typename(type), size) + 1;
 440                git_SHA1_Init(&c);
 441                git_SHA1_Update(&c, hdr, hdrlen);
 442        } else
 443                sha1 = NULL;
 444        if (type == OBJ_BLOB && size > big_file_threshold)
 445                buf = fixed_buf;
 446        else
 447                buf = xmalloc(size);
 448
 449        memset(&stream, 0, sizeof(stream));
 450        git_inflate_init(&stream);
 451        stream.next_out = buf;
 452        stream.avail_out = buf == fixed_buf ? sizeof(fixed_buf) : size;
 453
 454        do {
 455                unsigned char *last_out = stream.next_out;
 456                stream.next_in = fill(1);
 457                stream.avail_in = input_len;
 458                status = git_inflate(&stream, 0);
 459                use(input_len - stream.avail_in);
 460                if (sha1)
 461                        git_SHA1_Update(&c, last_out, stream.next_out - last_out);
 462                if (buf == fixed_buf) {
 463                        stream.next_out = buf;
 464                        stream.avail_out = sizeof(fixed_buf);
 465                }
 466        } while (status == Z_OK);
 467        if (stream.total_out != size || status != Z_STREAM_END)
 468                bad_object(offset, _("inflate returned %d"), status);
 469        git_inflate_end(&stream);
 470        if (sha1)
 471                git_SHA1_Final(sha1, &c);
 472        return buf == fixed_buf ? NULL : buf;
 473}
 474
 475static void *unpack_raw_entry(struct object_entry *obj,
 476                              union delta_base *delta_base,
 477                              unsigned char *sha1)
 478{
 479        unsigned char *p;
 480        unsigned long size, c;
 481        off_t base_offset;
 482        unsigned shift;
 483        void *data;
 484
 485        obj->idx.offset = consumed_bytes;
 486        input_crc32 = crc32(0, NULL, 0);
 487
 488        p = fill(1);
 489        c = *p;
 490        use(1);
 491        obj->type = (c >> 4) & 7;
 492        size = (c & 15);
 493        shift = 4;
 494        while (c & 0x80) {
 495                p = fill(1);
 496                c = *p;
 497                use(1);
 498                size += (c & 0x7f) << shift;
 499                shift += 7;
 500        }
 501        obj->size = size;
 502
 503        switch (obj->type) {
 504        case OBJ_REF_DELTA:
 505                hashcpy(delta_base->sha1, fill(20));
 506                use(20);
 507                break;
 508        case OBJ_OFS_DELTA:
 509                memset(delta_base, 0, sizeof(*delta_base));
 510                p = fill(1);
 511                c = *p;
 512                use(1);
 513                base_offset = c & 127;
 514                while (c & 128) {
 515                        base_offset += 1;
 516                        if (!base_offset || MSB(base_offset, 7))
 517                                bad_object(obj->idx.offset, _("offset value overflow for delta base object"));
 518                        p = fill(1);
 519                        c = *p;
 520                        use(1);
 521                        base_offset = (base_offset << 7) + (c & 127);
 522                }
 523                delta_base->offset = obj->idx.offset - base_offset;
 524                if (delta_base->offset <= 0 || delta_base->offset >= obj->idx.offset)
 525                        bad_object(obj->idx.offset, _("delta base offset is out of bound"));
 526                break;
 527        case OBJ_COMMIT:
 528        case OBJ_TREE:
 529        case OBJ_BLOB:
 530        case OBJ_TAG:
 531                break;
 532        default:
 533                bad_object(obj->idx.offset, _("unknown object type %d"), obj->type);
 534        }
 535        obj->hdr_size = consumed_bytes - obj->idx.offset;
 536
 537        data = unpack_entry_data(obj->idx.offset, obj->size, obj->type, sha1);
 538        obj->idx.crc32 = input_crc32;
 539        return data;
 540}
 541
 542static void *unpack_data(struct object_entry *obj,
 543                         int (*consume)(const unsigned char *, unsigned long, void *),
 544                         void *cb_data)
 545{
 546        off_t from = obj[0].idx.offset + obj[0].hdr_size;
 547        unsigned long len = obj[1].idx.offset - from;
 548        unsigned char *data, *inbuf;
 549        git_zstream stream;
 550        int status;
 551
 552        data = xmalloc(consume ? 64*1024 : obj->size);
 553        inbuf = xmalloc((len < 64*1024) ? len : 64*1024);
 554
 555        memset(&stream, 0, sizeof(stream));
 556        git_inflate_init(&stream);
 557        stream.next_out = data;
 558        stream.avail_out = consume ? 64*1024 : obj->size;
 559
 560        do {
 561                ssize_t n = (len < 64*1024) ? len : 64*1024;
 562                n = xpread(get_thread_data()->pack_fd, inbuf, n, from);
 563                if (n < 0)
 564                        die_errno(_("cannot pread pack file"));
 565                if (!n)
 566                        die(Q_("premature end of pack file, %lu byte missing",
 567                               "premature end of pack file, %lu bytes missing",
 568                               len),
 569                            len);
 570                from += n;
 571                len -= n;
 572                stream.next_in = inbuf;
 573                stream.avail_in = n;
 574                if (!consume)
 575                        status = git_inflate(&stream, 0);
 576                else {
 577                        do {
 578                                status = git_inflate(&stream, 0);
 579                                if (consume(data, stream.next_out - data, cb_data)) {
 580                                        free(inbuf);
 581                                        free(data);
 582                                        return NULL;
 583                                }
 584                                stream.next_out = data;
 585                                stream.avail_out = 64*1024;
 586                        } while (status == Z_OK && stream.avail_in);
 587                }
 588        } while (len && status == Z_OK && !stream.avail_in);
 589
 590        /* This has been inflated OK when first encountered, so... */
 591        if (status != Z_STREAM_END || stream.total_out != obj->size)
 592                die(_("serious inflate inconsistency"));
 593
 594        git_inflate_end(&stream);
 595        free(inbuf);
 596        if (consume) {
 597                free(data);
 598                data = NULL;
 599        }
 600        return data;
 601}
 602
 603static void *get_data_from_pack(struct object_entry *obj)
 604{
 605        return unpack_data(obj, NULL, NULL);
 606}
 607
 608static int compare_delta_bases(const union delta_base *base1,
 609                               const union delta_base *base2,
 610                               enum object_type type1,
 611                               enum object_type type2)
 612{
 613        int cmp = type1 - type2;
 614        if (cmp)
 615                return cmp;
 616        return memcmp(base1, base2, UNION_BASE_SZ);
 617}
 618
 619static int find_delta(const union delta_base *base, enum object_type type)
 620{
 621        int first = 0, last = nr_deltas;
 622
 623        while (first < last) {
 624                int next = (first + last) / 2;
 625                struct delta_entry *delta = &deltas[next];
 626                int cmp;
 627
 628                cmp = compare_delta_bases(base, &delta->base,
 629                                          type, objects[delta->obj_no].type);
 630                if (!cmp)
 631                        return next;
 632                if (cmp < 0) {
 633                        last = next;
 634                        continue;
 635                }
 636                first = next+1;
 637        }
 638        return -first-1;
 639}
 640
 641static void find_delta_children(const union delta_base *base,
 642                                int *first_index, int *last_index,
 643                                enum object_type type)
 644{
 645        int first = find_delta(base, type);
 646        int last = first;
 647        int end = nr_deltas - 1;
 648
 649        if (first < 0) {
 650                *first_index = 0;
 651                *last_index = -1;
 652                return;
 653        }
 654        while (first > 0 && !memcmp(&deltas[first - 1].base, base, UNION_BASE_SZ))
 655                --first;
 656        while (last < end && !memcmp(&deltas[last + 1].base, base, UNION_BASE_SZ))
 657                ++last;
 658        *first_index = first;
 659        *last_index = last;
 660}
 661
 662struct compare_data {
 663        struct object_entry *entry;
 664        struct git_istream *st;
 665        unsigned char *buf;
 666        unsigned long buf_size;
 667};
 668
 669static int compare_objects(const unsigned char *buf, unsigned long size,
 670                           void *cb_data)
 671{
 672        struct compare_data *data = cb_data;
 673
 674        if (data->buf_size < size) {
 675                free(data->buf);
 676                data->buf = xmalloc(size);
 677                data->buf_size = size;
 678        }
 679
 680        while (size) {
 681                ssize_t len = read_istream(data->st, data->buf, size);
 682                if (len == 0)
 683                        die(_("SHA1 COLLISION FOUND WITH %s !"),
 684                            sha1_to_hex(data->entry->idx.sha1));
 685                if (len < 0)
 686                        die(_("unable to read %s"),
 687                            sha1_to_hex(data->entry->idx.sha1));
 688                if (memcmp(buf, data->buf, len))
 689                        die(_("SHA1 COLLISION FOUND WITH %s !"),
 690                            sha1_to_hex(data->entry->idx.sha1));
 691                size -= len;
 692                buf += len;
 693        }
 694        return 0;
 695}
 696
 697static int check_collison(struct object_entry *entry)
 698{
 699        struct compare_data data;
 700        enum object_type type;
 701        unsigned long size;
 702
 703        if (entry->size <= big_file_threshold || entry->type != OBJ_BLOB)
 704                return -1;
 705
 706        memset(&data, 0, sizeof(data));
 707        data.entry = entry;
 708        data.st = open_istream(entry->idx.sha1, &type, &size, NULL);
 709        if (!data.st)
 710                return -1;
 711        if (size != entry->size || type != entry->type)
 712                die(_("SHA1 COLLISION FOUND WITH %s !"),
 713                    sha1_to_hex(entry->idx.sha1));
 714        unpack_data(entry, compare_objects, &data);
 715        close_istream(data.st);
 716        free(data.buf);
 717        return 0;
 718}
 719
 720static void sha1_object(const void *data, struct object_entry *obj_entry,
 721                        unsigned long size, enum object_type type,
 722                        const unsigned char *sha1)
 723{
 724        void *new_data = NULL;
 725        int collision_test_needed;
 726
 727        assert(data || obj_entry);
 728
 729        read_lock();
 730        collision_test_needed = has_sha1_file(sha1);
 731        read_unlock();
 732
 733        if (collision_test_needed && !data) {
 734                read_lock();
 735                if (!check_collison(obj_entry))
 736                        collision_test_needed = 0;
 737                read_unlock();
 738        }
 739        if (collision_test_needed) {
 740                void *has_data;
 741                enum object_type has_type;
 742                unsigned long has_size;
 743                read_lock();
 744                has_type = sha1_object_info(sha1, &has_size);
 745                if (has_type != type || has_size != size)
 746                        die(_("SHA1 COLLISION FOUND WITH %s !"), sha1_to_hex(sha1));
 747                has_data = read_sha1_file(sha1, &has_type, &has_size);
 748                read_unlock();
 749                if (!data)
 750                        data = new_data = get_data_from_pack(obj_entry);
 751                if (!has_data)
 752                        die(_("cannot read existing object %s"), sha1_to_hex(sha1));
 753                if (size != has_size || type != has_type ||
 754                    memcmp(data, has_data, size) != 0)
 755                        die(_("SHA1 COLLISION FOUND WITH %s !"), sha1_to_hex(sha1));
 756                free(has_data);
 757        }
 758
 759        if (strict) {
 760                read_lock();
 761                if (type == OBJ_BLOB) {
 762                        struct blob *blob = lookup_blob(sha1);
 763                        if (blob)
 764                                blob->object.flags |= FLAG_CHECKED;
 765                        else
 766                                die(_("invalid blob object %s"), sha1_to_hex(sha1));
 767                } else {
 768                        struct object *obj;
 769                        int eaten;
 770                        void *buf = (void *) data;
 771
 772                        assert(data && "data can only be NULL for large _blobs_");
 773
 774                        /*
 775                         * we do not need to free the memory here, as the
 776                         * buf is deleted by the caller.
 777                         */
 778                        obj = parse_object_buffer(sha1, type, size, buf, &eaten);
 779                        if (!obj)
 780                                die(_("invalid %s"), typename(type));
 781                        if (do_fsck_object &&
 782                            fsck_object(obj, buf, size, 1,
 783                                    fsck_error_function))
 784                                die(_("Error in object"));
 785                        if (fsck_walk(obj, mark_link, NULL))
 786                                die(_("Not all child objects of %s are reachable"), sha1_to_hex(obj->sha1));
 787
 788                        if (obj->type == OBJ_TREE) {
 789                                struct tree *item = (struct tree *) obj;
 790                                item->buffer = NULL;
 791                                obj->parsed = 0;
 792                        }
 793                        if (obj->type == OBJ_COMMIT) {
 794                                struct commit *commit = (struct commit *) obj;
 795                                if (detach_commit_buffer(commit, NULL) != data)
 796                                        die("BUG: parse_object_buffer transmogrified our buffer");
 797                        }
 798                        obj->flags |= FLAG_CHECKED;
 799                }
 800                read_unlock();
 801        }
 802
 803        free(new_data);
 804}
 805
 806/*
 807 * This function is part of find_unresolved_deltas(). There are two
 808 * walkers going in the opposite ways.
 809 *
 810 * The first one in find_unresolved_deltas() traverses down from
 811 * parent node to children, deflating nodes along the way. However,
 812 * memory for deflated nodes is limited by delta_base_cache_limit, so
 813 * at some point parent node's deflated content may be freed.
 814 *
 815 * The second walker is this function, which goes from current node up
 816 * to top parent if necessary to deflate the node. In normal
 817 * situation, its parent node would be already deflated, so it just
 818 * needs to apply delta.
 819 *
 820 * In the worst case scenario, parent node is no longer deflated because
 821 * we're running out of delta_base_cache_limit; we need to re-deflate
 822 * parents, possibly up to the top base.
 823 *
 824 * All deflated objects here are subject to be freed if we exceed
 825 * delta_base_cache_limit, just like in find_unresolved_deltas(), we
 826 * just need to make sure the last node is not freed.
 827 */
 828static void *get_base_data(struct base_data *c)
 829{
 830        if (!c->data) {
 831                struct object_entry *obj = c->obj;
 832                struct base_data **delta = NULL;
 833                int delta_nr = 0, delta_alloc = 0;
 834
 835                while (is_delta_type(c->obj->type) && !c->data) {
 836                        ALLOC_GROW(delta, delta_nr + 1, delta_alloc);
 837                        delta[delta_nr++] = c;
 838                        c = c->base;
 839                }
 840                if (!delta_nr) {
 841                        c->data = get_data_from_pack(obj);
 842                        c->size = obj->size;
 843                        get_thread_data()->base_cache_used += c->size;
 844                        prune_base_data(c);
 845                }
 846                for (; delta_nr > 0; delta_nr--) {
 847                        void *base, *raw;
 848                        c = delta[delta_nr - 1];
 849                        obj = c->obj;
 850                        base = get_base_data(c->base);
 851                        raw = get_data_from_pack(obj);
 852                        c->data = patch_delta(
 853                                base, c->base->size,
 854                                raw, obj->size,
 855                                &c->size);
 856                        free(raw);
 857                        if (!c->data)
 858                                bad_object(obj->idx.offset, _("failed to apply delta"));
 859                        get_thread_data()->base_cache_used += c->size;
 860                        prune_base_data(c);
 861                }
 862                free(delta);
 863        }
 864        return c->data;
 865}
 866
 867static void resolve_delta(struct object_entry *delta_obj,
 868                          struct base_data *base, struct base_data *result)
 869{
 870        void *base_data, *delta_data;
 871
 872        if (show_stat) {
 873                delta_obj->delta_depth = base->obj->delta_depth + 1;
 874                deepest_delta_lock();
 875                if (deepest_delta < delta_obj->delta_depth)
 876                        deepest_delta = delta_obj->delta_depth;
 877                deepest_delta_unlock();
 878        }
 879        delta_obj->base_object_no = base->obj - objects;
 880        delta_data = get_data_from_pack(delta_obj);
 881        base_data = get_base_data(base);
 882        result->obj = delta_obj;
 883        result->data = patch_delta(base_data, base->size,
 884                                   delta_data, delta_obj->size, &result->size);
 885        free(delta_data);
 886        if (!result->data)
 887                bad_object(delta_obj->idx.offset, _("failed to apply delta"));
 888        hash_sha1_file(result->data, result->size,
 889                       typename(delta_obj->real_type), delta_obj->idx.sha1);
 890        sha1_object(result->data, NULL, result->size, delta_obj->real_type,
 891                    delta_obj->idx.sha1);
 892        counter_lock();
 893        nr_resolved_deltas++;
 894        counter_unlock();
 895}
 896
 897/*
 898 * Standard boolean compare-and-swap: atomically check whether "*type" is
 899 * "want"; if so, swap in "set" and return true. Otherwise, leave it untouched
 900 * and return false.
 901 */
 902static int compare_and_swap_type(enum object_type *type,
 903                                 enum object_type want,
 904                                 enum object_type set)
 905{
 906        enum object_type old;
 907
 908        type_cas_lock();
 909        old = *type;
 910        if (old == want)
 911                *type = set;
 912        type_cas_unlock();
 913
 914        return old == want;
 915}
 916
 917static struct base_data *find_unresolved_deltas_1(struct base_data *base,
 918                                                  struct base_data *prev_base)
 919{
 920        if (base->ref_last == -1 && base->ofs_last == -1) {
 921                union delta_base base_spec;
 922
 923                hashcpy(base_spec.sha1, base->obj->idx.sha1);
 924                find_delta_children(&base_spec,
 925                                    &base->ref_first, &base->ref_last, OBJ_REF_DELTA);
 926
 927                memset(&base_spec, 0, sizeof(base_spec));
 928                base_spec.offset = base->obj->idx.offset;
 929                find_delta_children(&base_spec,
 930                                    &base->ofs_first, &base->ofs_last, OBJ_OFS_DELTA);
 931
 932                if (base->ref_last == -1 && base->ofs_last == -1) {
 933                        free(base->data);
 934                        return NULL;
 935                }
 936
 937                link_base_data(prev_base, base);
 938        }
 939
 940        if (base->ref_first <= base->ref_last) {
 941                struct object_entry *child = objects + deltas[base->ref_first].obj_no;
 942                struct base_data *result = alloc_base_data();
 943
 944                if (!compare_and_swap_type(&child->real_type, OBJ_REF_DELTA,
 945                                           base->obj->real_type))
 946                        die("BUG: child->real_type != OBJ_REF_DELTA");
 947
 948                resolve_delta(child, base, result);
 949                if (base->ref_first == base->ref_last && base->ofs_last == -1)
 950                        free_base_data(base);
 951
 952                base->ref_first++;
 953                return result;
 954        }
 955
 956        if (base->ofs_first <= base->ofs_last) {
 957                struct object_entry *child = objects + deltas[base->ofs_first].obj_no;
 958                struct base_data *result = alloc_base_data();
 959
 960                assert(child->real_type == OBJ_OFS_DELTA);
 961                child->real_type = base->obj->real_type;
 962                resolve_delta(child, base, result);
 963                if (base->ofs_first == base->ofs_last)
 964                        free_base_data(base);
 965
 966                base->ofs_first++;
 967                return result;
 968        }
 969
 970        unlink_base_data(base);
 971        return NULL;
 972}
 973
 974static void find_unresolved_deltas(struct base_data *base)
 975{
 976        struct base_data *new_base, *prev_base = NULL;
 977        for (;;) {
 978                new_base = find_unresolved_deltas_1(base, prev_base);
 979
 980                if (new_base) {
 981                        prev_base = base;
 982                        base = new_base;
 983                } else {
 984                        free(base);
 985                        base = prev_base;
 986                        if (!base)
 987                                return;
 988                        prev_base = base->base;
 989                }
 990        }
 991}
 992
 993static int compare_delta_entry(const void *a, const void *b)
 994{
 995        const struct delta_entry *delta_a = a;
 996        const struct delta_entry *delta_b = b;
 997
 998        /* group by type (ref vs ofs) and then by value (sha-1 or offset) */
 999        return compare_delta_bases(&delta_a->base, &delta_b->base,
1000                                   objects[delta_a->obj_no].type,
1001                                   objects[delta_b->obj_no].type);
1002}
1003
1004static void resolve_base(struct object_entry *obj)
1005{
1006        struct base_data *base_obj = alloc_base_data();
1007        base_obj->obj = obj;
1008        base_obj->data = NULL;
1009        find_unresolved_deltas(base_obj);
1010}
1011
1012#ifndef NO_PTHREADS
1013static void *threaded_second_pass(void *data)
1014{
1015        set_thread_data(data);
1016        for (;;) {
1017                int i;
1018                counter_lock();
1019                display_progress(progress, nr_resolved_deltas);
1020                counter_unlock();
1021                work_lock();
1022                while (nr_dispatched < nr_objects &&
1023                       is_delta_type(objects[nr_dispatched].type))
1024                        nr_dispatched++;
1025                if (nr_dispatched >= nr_objects) {
1026                        work_unlock();
1027                        break;
1028                }
1029                i = nr_dispatched++;
1030                work_unlock();
1031
1032                resolve_base(&objects[i]);
1033        }
1034        return NULL;
1035}
1036#endif
1037
1038/*
1039 * First pass:
1040 * - find locations of all objects;
1041 * - calculate SHA1 of all non-delta objects;
1042 * - remember base (SHA1 or offset) for all deltas.
1043 */
1044static void parse_pack_objects(unsigned char *sha1)
1045{
1046        int i, nr_delays = 0;
1047        struct delta_entry *delta = deltas;
1048        struct stat st;
1049
1050        if (verbose)
1051                progress = start_progress(
1052                                from_stdin ? _("Receiving objects") : _("Indexing objects"),
1053                                nr_objects);
1054        for (i = 0; i < nr_objects; i++) {
1055                struct object_entry *obj = &objects[i];
1056                void *data = unpack_raw_entry(obj, &delta->base, obj->idx.sha1);
1057                obj->real_type = obj->type;
1058                if (is_delta_type(obj->type)) {
1059                        nr_deltas++;
1060                        delta->obj_no = i;
1061                        delta++;
1062                } else if (!data) {
1063                        /* large blobs, check later */
1064                        obj->real_type = OBJ_BAD;
1065                        nr_delays++;
1066                } else
1067                        sha1_object(data, NULL, obj->size, obj->type, obj->idx.sha1);
1068                free(data);
1069                display_progress(progress, i+1);
1070        }
1071        objects[i].idx.offset = consumed_bytes;
1072        stop_progress(&progress);
1073
1074        /* Check pack integrity */
1075        flush();
1076        git_SHA1_Final(sha1, &input_ctx);
1077        if (hashcmp(fill(20), sha1))
1078                die(_("pack is corrupted (SHA1 mismatch)"));
1079        use(20);
1080
1081        /* If input_fd is a file, we should have reached its end now. */
1082        if (fstat(input_fd, &st))
1083                die_errno(_("cannot fstat packfile"));
1084        if (S_ISREG(st.st_mode) &&
1085                        lseek(input_fd, 0, SEEK_CUR) - input_len != st.st_size)
1086                die(_("pack has junk at the end"));
1087
1088        for (i = 0; i < nr_objects; i++) {
1089                struct object_entry *obj = &objects[i];
1090                if (obj->real_type != OBJ_BAD)
1091                        continue;
1092                obj->real_type = obj->type;
1093                sha1_object(NULL, obj, obj->size, obj->type, obj->idx.sha1);
1094                nr_delays--;
1095        }
1096        if (nr_delays)
1097                die(_("confusion beyond insanity in parse_pack_objects()"));
1098}
1099
1100/*
1101 * Second pass:
1102 * - for all non-delta objects, look if it is used as a base for
1103 *   deltas;
1104 * - if used as a base, uncompress the object and apply all deltas,
1105 *   recursively checking if the resulting object is used as a base
1106 *   for some more deltas.
1107 */
1108static void resolve_deltas(void)
1109{
1110        int i;
1111
1112        if (!nr_deltas)
1113                return;
1114
1115        /* Sort deltas by base SHA1/offset for fast searching */
1116        qsort(deltas, nr_deltas, sizeof(struct delta_entry),
1117              compare_delta_entry);
1118
1119        if (verbose)
1120                progress = start_progress(_("Resolving deltas"), nr_deltas);
1121
1122#ifndef NO_PTHREADS
1123        nr_dispatched = 0;
1124        if (nr_threads > 1 || getenv("GIT_FORCE_THREADS")) {
1125                init_thread();
1126                for (i = 0; i < nr_threads; i++) {
1127                        int ret = pthread_create(&thread_data[i].thread, NULL,
1128                                                 threaded_second_pass, thread_data + i);
1129                        if (ret)
1130                                die(_("unable to create thread: %s"),
1131                                    strerror(ret));
1132                }
1133                for (i = 0; i < nr_threads; i++)
1134                        pthread_join(thread_data[i].thread, NULL);
1135                cleanup_thread();
1136                return;
1137        }
1138#endif
1139
1140        for (i = 0; i < nr_objects; i++) {
1141                struct object_entry *obj = &objects[i];
1142
1143                if (is_delta_type(obj->type))
1144                        continue;
1145                resolve_base(obj);
1146                display_progress(progress, nr_resolved_deltas);
1147        }
1148}
1149
1150/*
1151 * Third pass:
1152 * - append objects to convert thin pack to full pack if required
1153 * - write the final 20-byte SHA-1
1154 */
1155static void fix_unresolved_deltas(struct sha1file *f, int nr_unresolved);
1156static void conclude_pack(int fix_thin_pack, const char *curr_pack, unsigned char *pack_sha1)
1157{
1158        if (nr_deltas == nr_resolved_deltas) {
1159                stop_progress(&progress);
1160                /* Flush remaining pack final 20-byte SHA1. */
1161                flush();
1162                return;
1163        }
1164
1165        if (fix_thin_pack) {
1166                struct sha1file *f;
1167                unsigned char read_sha1[20], tail_sha1[20];
1168                struct strbuf msg = STRBUF_INIT;
1169                int nr_unresolved = nr_deltas - nr_resolved_deltas;
1170                int nr_objects_initial = nr_objects;
1171                if (nr_unresolved <= 0)
1172                        die(_("confusion beyond insanity"));
1173                REALLOC_ARRAY(objects, nr_objects + nr_unresolved + 1);
1174                memset(objects + nr_objects + 1, 0,
1175                       nr_unresolved * sizeof(*objects));
1176                f = sha1fd(output_fd, curr_pack);
1177                fix_unresolved_deltas(f, nr_unresolved);
1178                strbuf_addf(&msg, _("completed with %d local objects"),
1179                            nr_objects - nr_objects_initial);
1180                stop_progress_msg(&progress, msg.buf);
1181                strbuf_release(&msg);
1182                sha1close(f, tail_sha1, 0);
1183                hashcpy(read_sha1, pack_sha1);
1184                fixup_pack_header_footer(output_fd, pack_sha1,
1185                                         curr_pack, nr_objects,
1186                                         read_sha1, consumed_bytes-20);
1187                if (hashcmp(read_sha1, tail_sha1) != 0)
1188                        die(_("Unexpected tail checksum for %s "
1189                              "(disk corruption?)"), curr_pack);
1190        }
1191        if (nr_deltas != nr_resolved_deltas)
1192                die(Q_("pack has %d unresolved delta",
1193                       "pack has %d unresolved deltas",
1194                       nr_deltas - nr_resolved_deltas),
1195                    nr_deltas - nr_resolved_deltas);
1196}
1197
1198static int write_compressed(struct sha1file *f, void *in, unsigned int size)
1199{
1200        git_zstream stream;
1201        int status;
1202        unsigned char outbuf[4096];
1203
1204        memset(&stream, 0, sizeof(stream));
1205        git_deflate_init(&stream, zlib_compression_level);
1206        stream.next_in = in;
1207        stream.avail_in = size;
1208
1209        do {
1210                stream.next_out = outbuf;
1211                stream.avail_out = sizeof(outbuf);
1212                status = git_deflate(&stream, Z_FINISH);
1213                sha1write(f, outbuf, sizeof(outbuf) - stream.avail_out);
1214        } while (status == Z_OK);
1215
1216        if (status != Z_STREAM_END)
1217                die(_("unable to deflate appended object (%d)"), status);
1218        size = stream.total_out;
1219        git_deflate_end(&stream);
1220        return size;
1221}
1222
1223static struct object_entry *append_obj_to_pack(struct sha1file *f,
1224                               const unsigned char *sha1, void *buf,
1225                               unsigned long size, enum object_type type)
1226{
1227        struct object_entry *obj = &objects[nr_objects++];
1228        unsigned char header[10];
1229        unsigned long s = size;
1230        int n = 0;
1231        unsigned char c = (type << 4) | (s & 15);
1232        s >>= 4;
1233        while (s) {
1234                header[n++] = c | 0x80;
1235                c = s & 0x7f;
1236                s >>= 7;
1237        }
1238        header[n++] = c;
1239        crc32_begin(f);
1240        sha1write(f, header, n);
1241        obj[0].size = size;
1242        obj[0].hdr_size = n;
1243        obj[0].type = type;
1244        obj[0].real_type = type;
1245        obj[1].idx.offset = obj[0].idx.offset + n;
1246        obj[1].idx.offset += write_compressed(f, buf, size);
1247        obj[0].idx.crc32 = crc32_end(f);
1248        sha1flush(f);
1249        hashcpy(obj->idx.sha1, sha1);
1250        return obj;
1251}
1252
1253static int delta_pos_compare(const void *_a, const void *_b)
1254{
1255        struct delta_entry *a = *(struct delta_entry **)_a;
1256        struct delta_entry *b = *(struct delta_entry **)_b;
1257        return a->obj_no - b->obj_no;
1258}
1259
1260static void fix_unresolved_deltas(struct sha1file *f, int nr_unresolved)
1261{
1262        struct delta_entry **sorted_by_pos;
1263        int i, n = 0;
1264
1265        /*
1266         * Since many unresolved deltas may well be themselves base objects
1267         * for more unresolved deltas, we really want to include the
1268         * smallest number of base objects that would cover as much delta
1269         * as possible by picking the
1270         * trunc deltas first, allowing for other deltas to resolve without
1271         * additional base objects.  Since most base objects are to be found
1272         * before deltas depending on them, a good heuristic is to start
1273         * resolving deltas in the same order as their position in the pack.
1274         */
1275        sorted_by_pos = xmalloc(nr_unresolved * sizeof(*sorted_by_pos));
1276        for (i = 0; i < nr_deltas; i++) {
1277                if (objects[deltas[i].obj_no].real_type != OBJ_REF_DELTA)
1278                        continue;
1279                sorted_by_pos[n++] = &deltas[i];
1280        }
1281        qsort(sorted_by_pos, n, sizeof(*sorted_by_pos), delta_pos_compare);
1282
1283        for (i = 0; i < n; i++) {
1284                struct delta_entry *d = sorted_by_pos[i];
1285                enum object_type type;
1286                struct base_data *base_obj = alloc_base_data();
1287
1288                if (objects[d->obj_no].real_type != OBJ_REF_DELTA)
1289                        continue;
1290                base_obj->data = read_sha1_file(d->base.sha1, &type, &base_obj->size);
1291                if (!base_obj->data)
1292                        continue;
1293
1294                if (check_sha1_signature(d->base.sha1, base_obj->data,
1295                                base_obj->size, typename(type)))
1296                        die(_("local object %s is corrupt"), sha1_to_hex(d->base.sha1));
1297                base_obj->obj = append_obj_to_pack(f, d->base.sha1,
1298                                        base_obj->data, base_obj->size, type);
1299                find_unresolved_deltas(base_obj);
1300                display_progress(progress, nr_resolved_deltas);
1301        }
1302        free(sorted_by_pos);
1303}
1304
1305static void final(const char *final_pack_name, const char *curr_pack_name,
1306                  const char *final_index_name, const char *curr_index_name,
1307                  const char *keep_name, const char *keep_msg,
1308                  unsigned char *sha1)
1309{
1310        const char *report = "pack";
1311        char name[PATH_MAX];
1312        int err;
1313
1314        if (!from_stdin) {
1315                close(input_fd);
1316        } else {
1317                fsync_or_die(output_fd, curr_pack_name);
1318                err = close(output_fd);
1319                if (err)
1320                        die_errno(_("error while closing pack file"));
1321        }
1322
1323        if (keep_msg) {
1324                int keep_fd, keep_msg_len = strlen(keep_msg);
1325
1326                if (!keep_name)
1327                        keep_fd = odb_pack_keep(name, sizeof(name), sha1);
1328                else
1329                        keep_fd = open(keep_name, O_RDWR|O_CREAT|O_EXCL, 0600);
1330
1331                if (keep_fd < 0) {
1332                        if (errno != EEXIST)
1333                                die_errno(_("cannot write keep file '%s'"),
1334                                          keep_name ? keep_name : name);
1335                } else {
1336                        if (keep_msg_len > 0) {
1337                                write_or_die(keep_fd, keep_msg, keep_msg_len);
1338                                write_or_die(keep_fd, "\n", 1);
1339                        }
1340                        if (close(keep_fd) != 0)
1341                                die_errno(_("cannot close written keep file '%s'"),
1342                                          keep_name ? keep_name : name);
1343                        report = "keep";
1344                }
1345        }
1346
1347        if (final_pack_name != curr_pack_name) {
1348                if (!final_pack_name) {
1349                        snprintf(name, sizeof(name), "%s/pack/pack-%s.pack",
1350                                 get_object_directory(), sha1_to_hex(sha1));
1351                        final_pack_name = name;
1352                }
1353                if (move_temp_to_file(curr_pack_name, final_pack_name))
1354                        die(_("cannot store pack file"));
1355        } else if (from_stdin)
1356                chmod(final_pack_name, 0444);
1357
1358        if (final_index_name != curr_index_name) {
1359                if (!final_index_name) {
1360                        snprintf(name, sizeof(name), "%s/pack/pack-%s.idx",
1361                                 get_object_directory(), sha1_to_hex(sha1));
1362                        final_index_name = name;
1363                }
1364                if (move_temp_to_file(curr_index_name, final_index_name))
1365                        die(_("cannot store index file"));
1366        } else
1367                chmod(final_index_name, 0444);
1368
1369        if (!from_stdin) {
1370                printf("%s\n", sha1_to_hex(sha1));
1371        } else {
1372                char buf[48];
1373                int len = snprintf(buf, sizeof(buf), "%s\t%s\n",
1374                                   report, sha1_to_hex(sha1));
1375                write_or_die(1, buf, len);
1376
1377                /*
1378                 * Let's just mimic git-unpack-objects here and write
1379                 * the last part of the input buffer to stdout.
1380                 */
1381                while (input_len) {
1382                        err = xwrite(1, input_buffer + input_offset, input_len);
1383                        if (err <= 0)
1384                                break;
1385                        input_len -= err;
1386                        input_offset += err;
1387                }
1388        }
1389}
1390
1391static int git_index_pack_config(const char *k, const char *v, void *cb)
1392{
1393        struct pack_idx_option *opts = cb;
1394
1395        if (!strcmp(k, "pack.indexversion")) {
1396                opts->version = git_config_int(k, v);
1397                if (opts->version > 2)
1398                        die(_("bad pack.indexversion=%"PRIu32), opts->version);
1399                return 0;
1400        }
1401        if (!strcmp(k, "pack.threads")) {
1402                nr_threads = git_config_int(k, v);
1403                if (nr_threads < 0)
1404                        die(_("invalid number of threads specified (%d)"),
1405                            nr_threads);
1406#ifdef NO_PTHREADS
1407                if (nr_threads != 1)
1408                        warning(_("no threads support, ignoring %s"), k);
1409                nr_threads = 1;
1410#endif
1411                return 0;
1412        }
1413        return git_default_config(k, v, cb);
1414}
1415
1416static int cmp_uint32(const void *a_, const void *b_)
1417{
1418        uint32_t a = *((uint32_t *)a_);
1419        uint32_t b = *((uint32_t *)b_);
1420
1421        return (a < b) ? -1 : (a != b);
1422}
1423
1424static void read_v2_anomalous_offsets(struct packed_git *p,
1425                                      struct pack_idx_option *opts)
1426{
1427        const uint32_t *idx1, *idx2;
1428        uint32_t i;
1429
1430        /* The address of the 4-byte offset table */
1431        idx1 = (((const uint32_t *)p->index_data)
1432                + 2 /* 8-byte header */
1433                + 256 /* fan out */
1434                + 5 * p->num_objects /* 20-byte SHA-1 table */
1435                + p->num_objects /* CRC32 table */
1436                );
1437
1438        /* The address of the 8-byte offset table */
1439        idx2 = idx1 + p->num_objects;
1440
1441        for (i = 0; i < p->num_objects; i++) {
1442                uint32_t off = ntohl(idx1[i]);
1443                if (!(off & 0x80000000))
1444                        continue;
1445                off = off & 0x7fffffff;
1446                if (idx2[off * 2])
1447                        continue;
1448                /*
1449                 * The real offset is ntohl(idx2[off * 2]) in high 4
1450                 * octets, and ntohl(idx2[off * 2 + 1]) in low 4
1451                 * octets.  But idx2[off * 2] is Zero!!!
1452                 */
1453                ALLOC_GROW(opts->anomaly, opts->anomaly_nr + 1, opts->anomaly_alloc);
1454                opts->anomaly[opts->anomaly_nr++] = ntohl(idx2[off * 2 + 1]);
1455        }
1456
1457        if (1 < opts->anomaly_nr)
1458                qsort(opts->anomaly, opts->anomaly_nr, sizeof(uint32_t), cmp_uint32);
1459}
1460
1461static void read_idx_option(struct pack_idx_option *opts, const char *pack_name)
1462{
1463        struct packed_git *p = add_packed_git(pack_name, strlen(pack_name), 1);
1464
1465        if (!p)
1466                die(_("Cannot open existing pack file '%s'"), pack_name);
1467        if (open_pack_index(p))
1468                die(_("Cannot open existing pack idx file for '%s'"), pack_name);
1469
1470        /* Read the attributes from the existing idx file */
1471        opts->version = p->index_version;
1472
1473        if (opts->version == 2)
1474                read_v2_anomalous_offsets(p, opts);
1475
1476        /*
1477         * Get rid of the idx file as we do not need it anymore.
1478         * NEEDSWORK: extract this bit from free_pack_by_name() in
1479         * sha1_file.c, perhaps?  It shouldn't matter very much as we
1480         * know we haven't installed this pack (hence we never have
1481         * read anything from it).
1482         */
1483        close_pack_index(p);
1484        free(p);
1485}
1486
1487static void show_pack_info(int stat_only)
1488{
1489        int i, baseobjects = nr_objects - nr_deltas;
1490        unsigned long *chain_histogram = NULL;
1491
1492        if (deepest_delta)
1493                chain_histogram = xcalloc(deepest_delta, sizeof(unsigned long));
1494
1495        for (i = 0; i < nr_objects; i++) {
1496                struct object_entry *obj = &objects[i];
1497
1498                if (is_delta_type(obj->type))
1499                        chain_histogram[obj->delta_depth - 1]++;
1500                if (stat_only)
1501                        continue;
1502                printf("%s %-6s %lu %lu %"PRIuMAX,
1503                       sha1_to_hex(obj->idx.sha1),
1504                       typename(obj->real_type), obj->size,
1505                       (unsigned long)(obj[1].idx.offset - obj->idx.offset),
1506                       (uintmax_t)obj->idx.offset);
1507                if (is_delta_type(obj->type)) {
1508                        struct object_entry *bobj = &objects[obj->base_object_no];
1509                        printf(" %u %s", obj->delta_depth, sha1_to_hex(bobj->idx.sha1));
1510                }
1511                putchar('\n');
1512        }
1513
1514        if (baseobjects)
1515                printf_ln(Q_("non delta: %d object",
1516                             "non delta: %d objects",
1517                             baseobjects),
1518                          baseobjects);
1519        for (i = 0; i < deepest_delta; i++) {
1520                if (!chain_histogram[i])
1521                        continue;
1522                printf_ln(Q_("chain length = %d: %lu object",
1523                             "chain length = %d: %lu objects",
1524                             chain_histogram[i]),
1525                          i + 1,
1526                          chain_histogram[i]);
1527        }
1528}
1529
1530int cmd_index_pack(int argc, const char **argv, const char *prefix)
1531{
1532        int i, fix_thin_pack = 0, verify = 0, stat_only = 0;
1533        const char *curr_index;
1534        const char *index_name = NULL, *pack_name = NULL;
1535        const char *keep_name = NULL, *keep_msg = NULL;
1536        struct strbuf index_name_buf = STRBUF_INIT,
1537                      keep_name_buf = STRBUF_INIT;
1538        struct pack_idx_entry **idx_objects;
1539        struct pack_idx_option opts;
1540        unsigned char pack_sha1[20];
1541        unsigned foreign_nr = 1;        /* zero is a "good" value, assume bad */
1542
1543        if (argc == 2 && !strcmp(argv[1], "-h"))
1544                usage(index_pack_usage);
1545
1546        check_replace_refs = 0;
1547
1548        reset_pack_idx_option(&opts);
1549        git_config(git_index_pack_config, &opts);
1550        if (prefix && chdir(prefix))
1551                die(_("Cannot come back to cwd"));
1552
1553        for (i = 1; i < argc; i++) {
1554                const char *arg = argv[i];
1555
1556                if (*arg == '-') {
1557                        if (!strcmp(arg, "--stdin")) {
1558                                from_stdin = 1;
1559                        } else if (!strcmp(arg, "--fix-thin")) {
1560                                fix_thin_pack = 1;
1561                        } else if (!strcmp(arg, "--strict")) {
1562                                strict = 1;
1563                                do_fsck_object = 1;
1564                        } else if (!strcmp(arg, "--check-self-contained-and-connected")) {
1565                                strict = 1;
1566                                check_self_contained_and_connected = 1;
1567                        } else if (!strcmp(arg, "--verify")) {
1568                                verify = 1;
1569                        } else if (!strcmp(arg, "--verify-stat")) {
1570                                verify = 1;
1571                                show_stat = 1;
1572                        } else if (!strcmp(arg, "--verify-stat-only")) {
1573                                verify = 1;
1574                                show_stat = 1;
1575                                stat_only = 1;
1576                        } else if (!strcmp(arg, "--keep")) {
1577                                keep_msg = "";
1578                        } else if (starts_with(arg, "--keep=")) {
1579                                keep_msg = arg + 7;
1580                        } else if (starts_with(arg, "--threads=")) {
1581                                char *end;
1582                                nr_threads = strtoul(arg+10, &end, 0);
1583                                if (!arg[10] || *end || nr_threads < 0)
1584                                        usage(index_pack_usage);
1585#ifdef NO_PTHREADS
1586                                if (nr_threads != 1)
1587                                        warning(_("no threads support, "
1588                                                  "ignoring %s"), arg);
1589                                nr_threads = 1;
1590#endif
1591                        } else if (starts_with(arg, "--pack_header=")) {
1592                                struct pack_header *hdr;
1593                                char *c;
1594
1595                                hdr = (struct pack_header *)input_buffer;
1596                                hdr->hdr_signature = htonl(PACK_SIGNATURE);
1597                                hdr->hdr_version = htonl(strtoul(arg + 14, &c, 10));
1598                                if (*c != ',')
1599                                        die(_("bad %s"), arg);
1600                                hdr->hdr_entries = htonl(strtoul(c + 1, &c, 10));
1601                                if (*c)
1602                                        die(_("bad %s"), arg);
1603                                input_len = sizeof(*hdr);
1604                        } else if (!strcmp(arg, "-v")) {
1605                                verbose = 1;
1606                        } else if (!strcmp(arg, "-o")) {
1607                                if (index_name || (i+1) >= argc)
1608                                        usage(index_pack_usage);
1609                                index_name = argv[++i];
1610                        } else if (starts_with(arg, "--index-version=")) {
1611                                char *c;
1612                                opts.version = strtoul(arg + 16, &c, 10);
1613                                if (opts.version > 2)
1614                                        die(_("bad %s"), arg);
1615                                if (*c == ',')
1616                                        opts.off32_limit = strtoul(c+1, &c, 0);
1617                                if (*c || opts.off32_limit & 0x80000000)
1618                                        die(_("bad %s"), arg);
1619                        } else
1620                                usage(index_pack_usage);
1621                        continue;
1622                }
1623
1624                if (pack_name)
1625                        usage(index_pack_usage);
1626                pack_name = arg;
1627        }
1628
1629        if (!pack_name && !from_stdin)
1630                usage(index_pack_usage);
1631        if (fix_thin_pack && !from_stdin)
1632                die(_("--fix-thin cannot be used without --stdin"));
1633        if (!index_name && pack_name) {
1634                size_t len;
1635                if (!strip_suffix(pack_name, ".pack", &len))
1636                        die(_("packfile name '%s' does not end with '.pack'"),
1637                            pack_name);
1638                strbuf_add(&index_name_buf, pack_name, len);
1639                strbuf_addstr(&index_name_buf, ".idx");
1640                index_name = index_name_buf.buf;
1641        }
1642        if (keep_msg && !keep_name && pack_name) {
1643                size_t len;
1644                if (!strip_suffix(pack_name, ".pack", &len))
1645                        die(_("packfile name '%s' does not end with '.pack'"),
1646                            pack_name);
1647                strbuf_add(&keep_name_buf, pack_name, len);
1648                strbuf_addstr(&keep_name_buf, ".idx");
1649                keep_name = keep_name_buf.buf;
1650        }
1651        if (verify) {
1652                if (!index_name)
1653                        die(_("--verify with no packfile name given"));
1654                read_idx_option(&opts, index_name);
1655                opts.flags |= WRITE_IDX_VERIFY | WRITE_IDX_STRICT;
1656        }
1657        if (strict)
1658                opts.flags |= WRITE_IDX_STRICT;
1659
1660#ifndef NO_PTHREADS
1661        if (!nr_threads) {
1662                nr_threads = online_cpus();
1663                /* An experiment showed that more threads does not mean faster */
1664                if (nr_threads > 3)
1665                        nr_threads = 3;
1666        }
1667#endif
1668
1669        curr_pack = open_pack_file(pack_name);
1670        parse_pack_header();
1671        objects = xcalloc(nr_objects + 1, sizeof(struct object_entry));
1672        deltas = xcalloc(nr_objects, sizeof(struct delta_entry));
1673        parse_pack_objects(pack_sha1);
1674        resolve_deltas();
1675        conclude_pack(fix_thin_pack, curr_pack, pack_sha1);
1676        free(deltas);
1677        if (strict)
1678                foreign_nr = check_objects();
1679
1680        if (show_stat)
1681                show_pack_info(stat_only);
1682
1683        idx_objects = xmalloc((nr_objects) * sizeof(struct pack_idx_entry *));
1684        for (i = 0; i < nr_objects; i++)
1685                idx_objects[i] = &objects[i].idx;
1686        curr_index = write_idx_file(index_name, idx_objects, nr_objects, &opts, pack_sha1);
1687        free(idx_objects);
1688
1689        if (!verify)
1690                final(pack_name, curr_pack,
1691                      index_name, curr_index,
1692                      keep_name, keep_msg,
1693                      pack_sha1);
1694        else
1695                close(input_fd);
1696        free(objects);
1697        strbuf_release(&index_name_buf);
1698        strbuf_release(&keep_name_buf);
1699        if (pack_name == NULL)
1700                free((void *) curr_pack);
1701        if (index_name == NULL)
1702                free((void *) curr_index);
1703
1704        /*
1705         * Let the caller know this pack is not self contained
1706         */
1707        if (check_self_contained_and_connected && foreign_nr)
1708                return 1;
1709
1710        return 0;
1711}