builtin / index-pack.con commit Merge branch 'ah/unpack-trees-advice-messages' into maint (e69771c)
   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 char hdr_size;
  22        signed char type;
  23        signed char real_type;
  24};
  25
  26struct object_stat {
  27        unsigned delta_depth;
  28        int base_object_no;
  29};
  30
  31struct base_data {
  32        struct base_data *base;
  33        struct base_data *child;
  34        struct object_entry *obj;
  35        void *data;
  36        unsigned long size;
  37        int ref_first, ref_last;
  38        int ofs_first, ofs_last;
  39};
  40
  41struct thread_local {
  42#ifndef NO_PTHREADS
  43        pthread_t thread;
  44#endif
  45        struct base_data *base_cache;
  46        size_t base_cache_used;
  47        int pack_fd;
  48};
  49
  50#define FLAG_LINK (1u<<20)
  51#define FLAG_CHECKED (1u<<21)
  52
  53struct ofs_delta_entry {
  54        off_t offset;
  55        int obj_no;
  56};
  57
  58struct ref_delta_entry {
  59        unsigned char sha1[20];
  60        int obj_no;
  61};
  62
  63static struct object_entry *objects;
  64static struct object_stat *obj_stat;
  65static struct ofs_delta_entry *ofs_deltas;
  66static struct ref_delta_entry *ref_deltas;
  67static struct thread_local nothread_data;
  68static int nr_objects;
  69static int nr_ofs_deltas;
  70static int nr_ref_deltas;
  71static int ref_deltas_alloc;
  72static int nr_resolved_deltas;
  73static int nr_threads;
  74
  75static int from_stdin;
  76static int strict;
  77static int do_fsck_object;
  78static struct fsck_options fsck_options = FSCK_OPTIONS_STRICT;
  79static int verbose;
  80static int show_stat;
  81static int check_self_contained_and_connected;
  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;
  93static const char *curr_pack;
  94
  95#ifndef NO_PTHREADS
  96
  97static struct thread_local *thread_data;
  98static int nr_dispatched;
  99static int threads_active;
 100
 101static pthread_mutex_t read_mutex;
 102#define read_lock()             lock_mutex(&read_mutex)
 103#define read_unlock()           unlock_mutex(&read_mutex)
 104
 105static pthread_mutex_t counter_mutex;
 106#define counter_lock()          lock_mutex(&counter_mutex)
 107#define counter_unlock()        unlock_mutex(&counter_mutex)
 108
 109static pthread_mutex_t work_mutex;
 110#define work_lock()             lock_mutex(&work_mutex)
 111#define work_unlock()           unlock_mutex(&work_mutex)
 112
 113static pthread_mutex_t deepest_delta_mutex;
 114#define deepest_delta_lock()    lock_mutex(&deepest_delta_mutex)
 115#define deepest_delta_unlock()  unlock_mutex(&deepest_delta_mutex)
 116
 117static pthread_mutex_t type_cas_mutex;
 118#define type_cas_lock()         lock_mutex(&type_cas_mutex)
 119#define type_cas_unlock()       unlock_mutex(&type_cas_mutex)
 120
 121static pthread_key_t key;
 122
 123static inline void lock_mutex(pthread_mutex_t *mutex)
 124{
 125        if (threads_active)
 126                pthread_mutex_lock(mutex);
 127}
 128
 129static inline void unlock_mutex(pthread_mutex_t *mutex)
 130{
 131        if (threads_active)
 132                pthread_mutex_unlock(mutex);
 133}
 134
 135/*
 136 * Mutex and conditional variable can't be statically-initialized on Windows.
 137 */
 138static void init_thread(void)
 139{
 140        int i;
 141        init_recursive_mutex(&read_mutex);
 142        pthread_mutex_init(&counter_mutex, NULL);
 143        pthread_mutex_init(&work_mutex, NULL);
 144        pthread_mutex_init(&type_cas_mutex, NULL);
 145        if (show_stat)
 146                pthread_mutex_init(&deepest_delta_mutex, NULL);
 147        pthread_key_create(&key, NULL);
 148        thread_data = xcalloc(nr_threads, sizeof(*thread_data));
 149        for (i = 0; i < nr_threads; i++) {
 150                thread_data[i].pack_fd = open(curr_pack, O_RDONLY);
 151                if (thread_data[i].pack_fd == -1)
 152                        die_errno(_("unable to open %s"), curr_pack);
 153        }
 154
 155        threads_active = 1;
 156}
 157
 158static void cleanup_thread(void)
 159{
 160        int i;
 161        if (!threads_active)
 162                return;
 163        threads_active = 0;
 164        pthread_mutex_destroy(&read_mutex);
 165        pthread_mutex_destroy(&counter_mutex);
 166        pthread_mutex_destroy(&work_mutex);
 167        pthread_mutex_destroy(&type_cas_mutex);
 168        if (show_stat)
 169                pthread_mutex_destroy(&deepest_delta_mutex);
 170        for (i = 0; i < nr_threads; i++)
 171                close(thread_data[i].pack_fd);
 172        pthread_key_delete(key);
 173        free(thread_data);
 174}
 175
 176#else
 177
 178#define read_lock()
 179#define read_unlock()
 180
 181#define counter_lock()
 182#define counter_unlock()
 183
 184#define work_lock()
 185#define work_unlock()
 186
 187#define deepest_delta_lock()
 188#define deepest_delta_unlock()
 189
 190#define type_cas_lock()
 191#define type_cas_unlock()
 192
 193#endif
 194
 195
 196static int mark_link(struct object *obj, int type, void *data, struct fsck_options *options)
 197{
 198        if (!obj)
 199                return -1;
 200
 201        if (type != OBJ_ANY && obj->type != type)
 202                die(_("object type mismatch at %s"), oid_to_hex(&obj->oid));
 203
 204        obj->flags |= FLAG_LINK;
 205        return 0;
 206}
 207
 208/* The content of each linked object must have been checked
 209   or it must be already present in the object database */
 210static unsigned check_object(struct object *obj)
 211{
 212        if (!obj)
 213                return 0;
 214
 215        if (!(obj->flags & FLAG_LINK))
 216                return 0;
 217
 218        if (!(obj->flags & FLAG_CHECKED)) {
 219                unsigned long size;
 220                int type = sha1_object_info(obj->oid.hash, &size);
 221                if (type <= 0)
 222                        die(_("did not receive expected object %s"),
 223                              oid_to_hex(&obj->oid));
 224                if (type != obj->type)
 225                        die(_("object %s: expected type %s, found %s"),
 226                            oid_to_hex(&obj->oid),
 227                            typename(obj->type), typename(type));
 228                obj->flags |= FLAG_CHECKED;
 229                return 1;
 230        }
 231
 232        return 0;
 233}
 234
 235static unsigned check_objects(void)
 236{
 237        unsigned i, max, foreign_nr = 0;
 238
 239        max = get_max_object_index();
 240        for (i = 0; i < max; i++)
 241                foreign_nr += check_object(get_indexed_object(i));
 242        return foreign_nr;
 243}
 244
 245
 246/* Discard current buffer used content. */
 247static void flush(void)
 248{
 249        if (input_offset) {
 250                if (output_fd >= 0)
 251                        write_or_die(output_fd, input_buffer, input_offset);
 252                git_SHA1_Update(&input_ctx, input_buffer, input_offset);
 253                memmove(input_buffer, input_buffer + input_offset, input_len);
 254                input_offset = 0;
 255        }
 256}
 257
 258/*
 259 * Make sure at least "min" bytes are available in the buffer, and
 260 * return the pointer to the buffer.
 261 */
 262static void *fill(int min)
 263{
 264        if (min <= input_len)
 265                return input_buffer + input_offset;
 266        if (min > sizeof(input_buffer))
 267                die(Q_("cannot fill %d byte",
 268                       "cannot fill %d bytes",
 269                       min),
 270                    min);
 271        flush();
 272        do {
 273                ssize_t ret = xread(input_fd, input_buffer + input_len,
 274                                sizeof(input_buffer) - input_len);
 275                if (ret <= 0) {
 276                        if (!ret)
 277                                die(_("early EOF"));
 278                        die_errno(_("read error on input"));
 279                }
 280                input_len += ret;
 281                if (from_stdin)
 282                        display_throughput(progress, consumed_bytes + input_len);
 283        } while (input_len < min);
 284        return input_buffer;
 285}
 286
 287static void use(int bytes)
 288{
 289        if (bytes > input_len)
 290                die(_("used more bytes than were available"));
 291        input_crc32 = crc32(input_crc32, input_buffer + input_offset, bytes);
 292        input_len -= bytes;
 293        input_offset += bytes;
 294
 295        /* make sure off_t is sufficiently large not to wrap */
 296        if (signed_add_overflows(consumed_bytes, bytes))
 297                die(_("pack too large for current definition of off_t"));
 298        consumed_bytes += bytes;
 299}
 300
 301static const char *open_pack_file(const char *pack_name)
 302{
 303        if (from_stdin) {
 304                input_fd = 0;
 305                if (!pack_name) {
 306                        static char tmp_file[PATH_MAX];
 307                        output_fd = odb_mkstemp(tmp_file, sizeof(tmp_file),
 308                                                "pack/tmp_pack_XXXXXX");
 309                        pack_name = xstrdup(tmp_file);
 310                } else
 311                        output_fd = open(pack_name, O_CREAT|O_EXCL|O_RDWR, 0600);
 312                if (output_fd < 0)
 313                        die_errno(_("unable to create '%s'"), pack_name);
 314                nothread_data.pack_fd = output_fd;
 315        } else {
 316                input_fd = open(pack_name, O_RDONLY);
 317                if (input_fd < 0)
 318                        die_errno(_("cannot open packfile '%s'"), pack_name);
 319                output_fd = -1;
 320                nothread_data.pack_fd = input_fd;
 321        }
 322        git_SHA1_Init(&input_ctx);
 323        return pack_name;
 324}
 325
 326static void parse_pack_header(void)
 327{
 328        struct pack_header *hdr = fill(sizeof(struct pack_header));
 329
 330        /* Header consistency check */
 331        if (hdr->hdr_signature != htonl(PACK_SIGNATURE))
 332                die(_("pack signature mismatch"));
 333        if (!pack_version_ok(hdr->hdr_version))
 334                die(_("pack version %"PRIu32" unsupported"),
 335                        ntohl(hdr->hdr_version));
 336
 337        nr_objects = ntohl(hdr->hdr_entries);
 338        use(sizeof(struct pack_header));
 339}
 340
 341static NORETURN void bad_object(off_t offset, const char *format,
 342                       ...) __attribute__((format (printf, 2, 3)));
 343
 344static NORETURN void bad_object(off_t offset, const char *format, ...)
 345{
 346        va_list params;
 347        char buf[1024];
 348
 349        va_start(params, format);
 350        vsnprintf(buf, sizeof(buf), format, params);
 351        va_end(params);
 352        die(_("pack has bad object at offset %"PRIuMAX": %s"),
 353            (uintmax_t)offset, buf);
 354}
 355
 356static inline struct thread_local *get_thread_data(void)
 357{
 358#ifndef NO_PTHREADS
 359        if (threads_active)
 360                return pthread_getspecific(key);
 361        assert(!threads_active &&
 362               "This should only be reached when all threads are gone");
 363#endif
 364        return &nothread_data;
 365}
 366
 367#ifndef NO_PTHREADS
 368static void set_thread_data(struct thread_local *data)
 369{
 370        if (threads_active)
 371                pthread_setspecific(key, data);
 372}
 373#endif
 374
 375static struct base_data *alloc_base_data(void)
 376{
 377        struct base_data *base = xcalloc(1, sizeof(struct base_data));
 378        base->ref_last = -1;
 379        base->ofs_last = -1;
 380        return base;
 381}
 382
 383static void free_base_data(struct base_data *c)
 384{
 385        if (c->data) {
 386                free(c->data);
 387                c->data = NULL;
 388                get_thread_data()->base_cache_used -= c->size;
 389        }
 390}
 391
 392static void prune_base_data(struct base_data *retain)
 393{
 394        struct base_data *b;
 395        struct thread_local *data = get_thread_data();
 396        for (b = data->base_cache;
 397             data->base_cache_used > delta_base_cache_limit && b;
 398             b = b->child) {
 399                if (b->data && b != retain)
 400                        free_base_data(b);
 401        }
 402}
 403
 404static void link_base_data(struct base_data *base, struct base_data *c)
 405{
 406        if (base)
 407                base->child = c;
 408        else
 409                get_thread_data()->base_cache = c;
 410
 411        c->base = base;
 412        c->child = NULL;
 413        if (c->data)
 414                get_thread_data()->base_cache_used += c->size;
 415        prune_base_data(c);
 416}
 417
 418static void unlink_base_data(struct base_data *c)
 419{
 420        struct base_data *base = c->base;
 421        if (base)
 422                base->child = NULL;
 423        else
 424                get_thread_data()->base_cache = NULL;
 425        free_base_data(c);
 426}
 427
 428static int is_delta_type(enum object_type type)
 429{
 430        return (type == OBJ_REF_DELTA || type == OBJ_OFS_DELTA);
 431}
 432
 433static void *unpack_entry_data(off_t offset, unsigned long size,
 434                               enum object_type type, unsigned char *sha1)
 435{
 436        static char fixed_buf[8192];
 437        int status;
 438        git_zstream stream;
 439        void *buf;
 440        git_SHA_CTX c;
 441        char hdr[32];
 442        int hdrlen;
 443
 444        if (!is_delta_type(type)) {
 445                hdrlen = xsnprintf(hdr, sizeof(hdr), "%s %lu", typename(type), size) + 1;
 446                git_SHA1_Init(&c);
 447                git_SHA1_Update(&c, hdr, hdrlen);
 448        } else
 449                sha1 = NULL;
 450        if (type == OBJ_BLOB && size > big_file_threshold)
 451                buf = fixed_buf;
 452        else
 453                buf = xmallocz(size);
 454
 455        memset(&stream, 0, sizeof(stream));
 456        git_inflate_init(&stream);
 457        stream.next_out = buf;
 458        stream.avail_out = buf == fixed_buf ? sizeof(fixed_buf) : size;
 459
 460        do {
 461                unsigned char *last_out = stream.next_out;
 462                stream.next_in = fill(1);
 463                stream.avail_in = input_len;
 464                status = git_inflate(&stream, 0);
 465                use(input_len - stream.avail_in);
 466                if (sha1)
 467                        git_SHA1_Update(&c, last_out, stream.next_out - last_out);
 468                if (buf == fixed_buf) {
 469                        stream.next_out = buf;
 470                        stream.avail_out = sizeof(fixed_buf);
 471                }
 472        } while (status == Z_OK);
 473        if (stream.total_out != size || status != Z_STREAM_END)
 474                bad_object(offset, _("inflate returned %d"), status);
 475        git_inflate_end(&stream);
 476        if (sha1)
 477                git_SHA1_Final(sha1, &c);
 478        return buf == fixed_buf ? NULL : buf;
 479}
 480
 481static void *unpack_raw_entry(struct object_entry *obj,
 482                              off_t *ofs_offset,
 483                              unsigned char *ref_sha1,
 484                              unsigned char *sha1)
 485{
 486        unsigned char *p;
 487        unsigned long size, c;
 488        off_t base_offset;
 489        unsigned shift;
 490        void *data;
 491
 492        obj->idx.offset = consumed_bytes;
 493        input_crc32 = crc32(0, NULL, 0);
 494
 495        p = fill(1);
 496        c = *p;
 497        use(1);
 498        obj->type = (c >> 4) & 7;
 499        size = (c & 15);
 500        shift = 4;
 501        while (c & 0x80) {
 502                p = fill(1);
 503                c = *p;
 504                use(1);
 505                size += (c & 0x7f) << shift;
 506                shift += 7;
 507        }
 508        obj->size = size;
 509
 510        switch (obj->type) {
 511        case OBJ_REF_DELTA:
 512                hashcpy(ref_sha1, fill(20));
 513                use(20);
 514                break;
 515        case OBJ_OFS_DELTA:
 516                p = fill(1);
 517                c = *p;
 518                use(1);
 519                base_offset = c & 127;
 520                while (c & 128) {
 521                        base_offset += 1;
 522                        if (!base_offset || MSB(base_offset, 7))
 523                                bad_object(obj->idx.offset, _("offset value overflow for delta base object"));
 524                        p = fill(1);
 525                        c = *p;
 526                        use(1);
 527                        base_offset = (base_offset << 7) + (c & 127);
 528                }
 529                *ofs_offset = obj->idx.offset - base_offset;
 530                if (*ofs_offset <= 0 || *ofs_offset >= obj->idx.offset)
 531                        bad_object(obj->idx.offset, _("delta base offset is out of bound"));
 532                break;
 533        case OBJ_COMMIT:
 534        case OBJ_TREE:
 535        case OBJ_BLOB:
 536        case OBJ_TAG:
 537                break;
 538        default:
 539                bad_object(obj->idx.offset, _("unknown object type %d"), obj->type);
 540        }
 541        obj->hdr_size = consumed_bytes - obj->idx.offset;
 542
 543        data = unpack_entry_data(obj->idx.offset, obj->size, obj->type, sha1);
 544        obj->idx.crc32 = input_crc32;
 545        return data;
 546}
 547
 548static void *unpack_data(struct object_entry *obj,
 549                         int (*consume)(const unsigned char *, unsigned long, void *),
 550                         void *cb_data)
 551{
 552        off_t from = obj[0].idx.offset + obj[0].hdr_size;
 553        off_t len = obj[1].idx.offset - from;
 554        unsigned char *data, *inbuf;
 555        git_zstream stream;
 556        int status;
 557
 558        data = xmallocz(consume ? 64*1024 : obj->size);
 559        inbuf = xmalloc((len < 64*1024) ? (int)len : 64*1024);
 560
 561        memset(&stream, 0, sizeof(stream));
 562        git_inflate_init(&stream);
 563        stream.next_out = data;
 564        stream.avail_out = consume ? 64*1024 : obj->size;
 565
 566        do {
 567                ssize_t n = (len < 64*1024) ? (ssize_t)len : 64*1024;
 568                n = xpread(get_thread_data()->pack_fd, inbuf, n, from);
 569                if (n < 0)
 570                        die_errno(_("cannot pread pack file"));
 571                if (!n)
 572                        die(Q_("premature end of pack file, %"PRIuMAX" byte missing",
 573                               "premature end of pack file, %"PRIuMAX" bytes missing",
 574                               (unsigned int)len),
 575                            (uintmax_t)len);
 576                from += n;
 577                len -= n;
 578                stream.next_in = inbuf;
 579                stream.avail_in = n;
 580                if (!consume)
 581                        status = git_inflate(&stream, 0);
 582                else {
 583                        do {
 584                                status = git_inflate(&stream, 0);
 585                                if (consume(data, stream.next_out - data, cb_data)) {
 586                                        free(inbuf);
 587                                        free(data);
 588                                        return NULL;
 589                                }
 590                                stream.next_out = data;
 591                                stream.avail_out = 64*1024;
 592                        } while (status == Z_OK && stream.avail_in);
 593                }
 594        } while (len && status == Z_OK && !stream.avail_in);
 595
 596        /* This has been inflated OK when first encountered, so... */
 597        if (status != Z_STREAM_END || stream.total_out != obj->size)
 598                die(_("serious inflate inconsistency"));
 599
 600        git_inflate_end(&stream);
 601        free(inbuf);
 602        if (consume) {
 603                free(data);
 604                data = NULL;
 605        }
 606        return data;
 607}
 608
 609static void *get_data_from_pack(struct object_entry *obj)
 610{
 611        return unpack_data(obj, NULL, NULL);
 612}
 613
 614static int compare_ofs_delta_bases(off_t offset1, off_t offset2,
 615                                   enum object_type type1,
 616                                   enum object_type type2)
 617{
 618        int cmp = type1 - type2;
 619        if (cmp)
 620                return cmp;
 621        return offset1 < offset2 ? -1 :
 622               offset1 > offset2 ?  1 :
 623               0;
 624}
 625
 626static int find_ofs_delta(const off_t offset, enum object_type type)
 627{
 628        int first = 0, last = nr_ofs_deltas;
 629
 630        while (first < last) {
 631                int next = (first + last) / 2;
 632                struct ofs_delta_entry *delta = &ofs_deltas[next];
 633                int cmp;
 634
 635                cmp = compare_ofs_delta_bases(offset, delta->offset,
 636                                              type, objects[delta->obj_no].type);
 637                if (!cmp)
 638                        return next;
 639                if (cmp < 0) {
 640                        last = next;
 641                        continue;
 642                }
 643                first = next+1;
 644        }
 645        return -first-1;
 646}
 647
 648static void find_ofs_delta_children(off_t offset,
 649                                    int *first_index, int *last_index,
 650                                    enum object_type type)
 651{
 652        int first = find_ofs_delta(offset, type);
 653        int last = first;
 654        int end = nr_ofs_deltas - 1;
 655
 656        if (first < 0) {
 657                *first_index = 0;
 658                *last_index = -1;
 659                return;
 660        }
 661        while (first > 0 && ofs_deltas[first - 1].offset == offset)
 662                --first;
 663        while (last < end && ofs_deltas[last + 1].offset == offset)
 664                ++last;
 665        *first_index = first;
 666        *last_index = last;
 667}
 668
 669static int compare_ref_delta_bases(const unsigned char *sha1,
 670                                   const unsigned char *sha2,
 671                                   enum object_type type1,
 672                                   enum object_type type2)
 673{
 674        int cmp = type1 - type2;
 675        if (cmp)
 676                return cmp;
 677        return hashcmp(sha1, sha2);
 678}
 679
 680static int find_ref_delta(const unsigned char *sha1, enum object_type type)
 681{
 682        int first = 0, last = nr_ref_deltas;
 683
 684        while (first < last) {
 685                int next = (first + last) / 2;
 686                struct ref_delta_entry *delta = &ref_deltas[next];
 687                int cmp;
 688
 689                cmp = compare_ref_delta_bases(sha1, delta->sha1,
 690                                              type, objects[delta->obj_no].type);
 691                if (!cmp)
 692                        return next;
 693                if (cmp < 0) {
 694                        last = next;
 695                        continue;
 696                }
 697                first = next+1;
 698        }
 699        return -first-1;
 700}
 701
 702static void find_ref_delta_children(const unsigned char *sha1,
 703                                    int *first_index, int *last_index,
 704                                    enum object_type type)
 705{
 706        int first = find_ref_delta(sha1, type);
 707        int last = first;
 708        int end = nr_ref_deltas - 1;
 709
 710        if (first < 0) {
 711                *first_index = 0;
 712                *last_index = -1;
 713                return;
 714        }
 715        while (first > 0 && !hashcmp(ref_deltas[first - 1].sha1, sha1))
 716                --first;
 717        while (last < end && !hashcmp(ref_deltas[last + 1].sha1, sha1))
 718                ++last;
 719        *first_index = first;
 720        *last_index = last;
 721}
 722
 723struct compare_data {
 724        struct object_entry *entry;
 725        struct git_istream *st;
 726        unsigned char *buf;
 727        unsigned long buf_size;
 728};
 729
 730static int compare_objects(const unsigned char *buf, unsigned long size,
 731                           void *cb_data)
 732{
 733        struct compare_data *data = cb_data;
 734
 735        if (data->buf_size < size) {
 736                free(data->buf);
 737                data->buf = xmalloc(size);
 738                data->buf_size = size;
 739        }
 740
 741        while (size) {
 742                ssize_t len = read_istream(data->st, data->buf, size);
 743                if (len == 0)
 744                        die(_("SHA1 COLLISION FOUND WITH %s !"),
 745                            sha1_to_hex(data->entry->idx.sha1));
 746                if (len < 0)
 747                        die(_("unable to read %s"),
 748                            sha1_to_hex(data->entry->idx.sha1));
 749                if (memcmp(buf, data->buf, len))
 750                        die(_("SHA1 COLLISION FOUND WITH %s !"),
 751                            sha1_to_hex(data->entry->idx.sha1));
 752                size -= len;
 753                buf += len;
 754        }
 755        return 0;
 756}
 757
 758static int check_collison(struct object_entry *entry)
 759{
 760        struct compare_data data;
 761        enum object_type type;
 762        unsigned long size;
 763
 764        if (entry->size <= big_file_threshold || entry->type != OBJ_BLOB)
 765                return -1;
 766
 767        memset(&data, 0, sizeof(data));
 768        data.entry = entry;
 769        data.st = open_istream(entry->idx.sha1, &type, &size, NULL);
 770        if (!data.st)
 771                return -1;
 772        if (size != entry->size || type != entry->type)
 773                die(_("SHA1 COLLISION FOUND WITH %s !"),
 774                    sha1_to_hex(entry->idx.sha1));
 775        unpack_data(entry, compare_objects, &data);
 776        close_istream(data.st);
 777        free(data.buf);
 778        return 0;
 779}
 780
 781static void sha1_object(const void *data, struct object_entry *obj_entry,
 782                        unsigned long size, enum object_type type,
 783                        const unsigned char *sha1)
 784{
 785        void *new_data = NULL;
 786        int collision_test_needed;
 787
 788        assert(data || obj_entry);
 789
 790        read_lock();
 791        collision_test_needed = has_sha1_file_with_flags(sha1, HAS_SHA1_QUICK);
 792        read_unlock();
 793
 794        if (collision_test_needed && !data) {
 795                read_lock();
 796                if (!check_collison(obj_entry))
 797                        collision_test_needed = 0;
 798                read_unlock();
 799        }
 800        if (collision_test_needed) {
 801                void *has_data;
 802                enum object_type has_type;
 803                unsigned long has_size;
 804                read_lock();
 805                has_type = sha1_object_info(sha1, &has_size);
 806                if (has_type != type || has_size != size)
 807                        die(_("SHA1 COLLISION FOUND WITH %s !"), sha1_to_hex(sha1));
 808                has_data = read_sha1_file(sha1, &has_type, &has_size);
 809                read_unlock();
 810                if (!data)
 811                        data = new_data = get_data_from_pack(obj_entry);
 812                if (!has_data)
 813                        die(_("cannot read existing object %s"), sha1_to_hex(sha1));
 814                if (size != has_size || type != has_type ||
 815                    memcmp(data, has_data, size) != 0)
 816                        die(_("SHA1 COLLISION FOUND WITH %s !"), sha1_to_hex(sha1));
 817                free(has_data);
 818        }
 819
 820        if (strict) {
 821                read_lock();
 822                if (type == OBJ_BLOB) {
 823                        struct blob *blob = lookup_blob(sha1);
 824                        if (blob)
 825                                blob->object.flags |= FLAG_CHECKED;
 826                        else
 827                                die(_("invalid blob object %s"), sha1_to_hex(sha1));
 828                } else {
 829                        struct object *obj;
 830                        int eaten;
 831                        void *buf = (void *) data;
 832
 833                        assert(data && "data can only be NULL for large _blobs_");
 834
 835                        /*
 836                         * we do not need to free the memory here, as the
 837                         * buf is deleted by the caller.
 838                         */
 839                        obj = parse_object_buffer(sha1, type, size, buf, &eaten);
 840                        if (!obj)
 841                                die(_("invalid %s"), typename(type));
 842                        if (do_fsck_object &&
 843                            fsck_object(obj, buf, size, &fsck_options))
 844                                die(_("Error in object"));
 845                        if (fsck_walk(obj, NULL, &fsck_options))
 846                                die(_("Not all child objects of %s are reachable"), oid_to_hex(&obj->oid));
 847
 848                        if (obj->type == OBJ_TREE) {
 849                                struct tree *item = (struct tree *) obj;
 850                                item->buffer = NULL;
 851                                obj->parsed = 0;
 852                        }
 853                        if (obj->type == OBJ_COMMIT) {
 854                                struct commit *commit = (struct commit *) obj;
 855                                if (detach_commit_buffer(commit, NULL) != data)
 856                                        die("BUG: parse_object_buffer transmogrified our buffer");
 857                        }
 858                        obj->flags |= FLAG_CHECKED;
 859                }
 860                read_unlock();
 861        }
 862
 863        free(new_data);
 864}
 865
 866/*
 867 * This function is part of find_unresolved_deltas(). There are two
 868 * walkers going in the opposite ways.
 869 *
 870 * The first one in find_unresolved_deltas() traverses down from
 871 * parent node to children, deflating nodes along the way. However,
 872 * memory for deflated nodes is limited by delta_base_cache_limit, so
 873 * at some point parent node's deflated content may be freed.
 874 *
 875 * The second walker is this function, which goes from current node up
 876 * to top parent if necessary to deflate the node. In normal
 877 * situation, its parent node would be already deflated, so it just
 878 * needs to apply delta.
 879 *
 880 * In the worst case scenario, parent node is no longer deflated because
 881 * we're running out of delta_base_cache_limit; we need to re-deflate
 882 * parents, possibly up to the top base.
 883 *
 884 * All deflated objects here are subject to be freed if we exceed
 885 * delta_base_cache_limit, just like in find_unresolved_deltas(), we
 886 * just need to make sure the last node is not freed.
 887 */
 888static void *get_base_data(struct base_data *c)
 889{
 890        if (!c->data) {
 891                struct object_entry *obj = c->obj;
 892                struct base_data **delta = NULL;
 893                int delta_nr = 0, delta_alloc = 0;
 894
 895                while (is_delta_type(c->obj->type) && !c->data) {
 896                        ALLOC_GROW(delta, delta_nr + 1, delta_alloc);
 897                        delta[delta_nr++] = c;
 898                        c = c->base;
 899                }
 900                if (!delta_nr) {
 901                        c->data = get_data_from_pack(obj);
 902                        c->size = obj->size;
 903                        get_thread_data()->base_cache_used += c->size;
 904                        prune_base_data(c);
 905                }
 906                for (; delta_nr > 0; delta_nr--) {
 907                        void *base, *raw;
 908                        c = delta[delta_nr - 1];
 909                        obj = c->obj;
 910                        base = get_base_data(c->base);
 911                        raw = get_data_from_pack(obj);
 912                        c->data = patch_delta(
 913                                base, c->base->size,
 914                                raw, obj->size,
 915                                &c->size);
 916                        free(raw);
 917                        if (!c->data)
 918                                bad_object(obj->idx.offset, _("failed to apply delta"));
 919                        get_thread_data()->base_cache_used += c->size;
 920                        prune_base_data(c);
 921                }
 922                free(delta);
 923        }
 924        return c->data;
 925}
 926
 927static void resolve_delta(struct object_entry *delta_obj,
 928                          struct base_data *base, struct base_data *result)
 929{
 930        void *base_data, *delta_data;
 931
 932        if (show_stat) {
 933                int i = delta_obj - objects;
 934                int j = base->obj - objects;
 935                obj_stat[i].delta_depth = obj_stat[j].delta_depth + 1;
 936                deepest_delta_lock();
 937                if (deepest_delta < obj_stat[i].delta_depth)
 938                        deepest_delta = obj_stat[i].delta_depth;
 939                deepest_delta_unlock();
 940                obj_stat[i].base_object_no = j;
 941        }
 942        delta_data = get_data_from_pack(delta_obj);
 943        base_data = get_base_data(base);
 944        result->obj = delta_obj;
 945        result->data = patch_delta(base_data, base->size,
 946                                   delta_data, delta_obj->size, &result->size);
 947        free(delta_data);
 948        if (!result->data)
 949                bad_object(delta_obj->idx.offset, _("failed to apply delta"));
 950        hash_sha1_file(result->data, result->size,
 951                       typename(delta_obj->real_type), delta_obj->idx.sha1);
 952        sha1_object(result->data, NULL, result->size, delta_obj->real_type,
 953                    delta_obj->idx.sha1);
 954        counter_lock();
 955        nr_resolved_deltas++;
 956        counter_unlock();
 957}
 958
 959/*
 960 * Standard boolean compare-and-swap: atomically check whether "*type" is
 961 * "want"; if so, swap in "set" and return true. Otherwise, leave it untouched
 962 * and return false.
 963 */
 964static int compare_and_swap_type(signed char *type,
 965                                 enum object_type want,
 966                                 enum object_type set)
 967{
 968        enum object_type old;
 969
 970        type_cas_lock();
 971        old = *type;
 972        if (old == want)
 973                *type = set;
 974        type_cas_unlock();
 975
 976        return old == want;
 977}
 978
 979static struct base_data *find_unresolved_deltas_1(struct base_data *base,
 980                                                  struct base_data *prev_base)
 981{
 982        if (base->ref_last == -1 && base->ofs_last == -1) {
 983                find_ref_delta_children(base->obj->idx.sha1,
 984                                        &base->ref_first, &base->ref_last,
 985                                        OBJ_REF_DELTA);
 986
 987                find_ofs_delta_children(base->obj->idx.offset,
 988                                        &base->ofs_first, &base->ofs_last,
 989                                        OBJ_OFS_DELTA);
 990
 991                if (base->ref_last == -1 && base->ofs_last == -1) {
 992                        free(base->data);
 993                        return NULL;
 994                }
 995
 996                link_base_data(prev_base, base);
 997        }
 998
 999        if (base->ref_first <= base->ref_last) {
1000                struct object_entry *child = objects + ref_deltas[base->ref_first].obj_no;
1001                struct base_data *result = alloc_base_data();
1002
1003                if (!compare_and_swap_type(&child->real_type, OBJ_REF_DELTA,
1004                                           base->obj->real_type))
1005                        die("BUG: child->real_type != OBJ_REF_DELTA");
1006
1007                resolve_delta(child, base, result);
1008                if (base->ref_first == base->ref_last && base->ofs_last == -1)
1009                        free_base_data(base);
1010
1011                base->ref_first++;
1012                return result;
1013        }
1014
1015        if (base->ofs_first <= base->ofs_last) {
1016                struct object_entry *child = objects + ofs_deltas[base->ofs_first].obj_no;
1017                struct base_data *result = alloc_base_data();
1018
1019                assert(child->real_type == OBJ_OFS_DELTA);
1020                child->real_type = base->obj->real_type;
1021                resolve_delta(child, base, result);
1022                if (base->ofs_first == base->ofs_last)
1023                        free_base_data(base);
1024
1025                base->ofs_first++;
1026                return result;
1027        }
1028
1029        unlink_base_data(base);
1030        return NULL;
1031}
1032
1033static void find_unresolved_deltas(struct base_data *base)
1034{
1035        struct base_data *new_base, *prev_base = NULL;
1036        for (;;) {
1037                new_base = find_unresolved_deltas_1(base, prev_base);
1038
1039                if (new_base) {
1040                        prev_base = base;
1041                        base = new_base;
1042                } else {
1043                        free(base);
1044                        base = prev_base;
1045                        if (!base)
1046                                return;
1047                        prev_base = base->base;
1048                }
1049        }
1050}
1051
1052static int compare_ofs_delta_entry(const void *a, const void *b)
1053{
1054        const struct ofs_delta_entry *delta_a = a;
1055        const struct ofs_delta_entry *delta_b = b;
1056
1057        return delta_a->offset < delta_b->offset ? -1 :
1058               delta_a->offset > delta_b->offset ?  1 :
1059               0;
1060}
1061
1062static int compare_ref_delta_entry(const void *a, const void *b)
1063{
1064        const struct ref_delta_entry *delta_a = a;
1065        const struct ref_delta_entry *delta_b = b;
1066
1067        return hashcmp(delta_a->sha1, delta_b->sha1);
1068}
1069
1070static void resolve_base(struct object_entry *obj)
1071{
1072        struct base_data *base_obj = alloc_base_data();
1073        base_obj->obj = obj;
1074        base_obj->data = NULL;
1075        find_unresolved_deltas(base_obj);
1076}
1077
1078#ifndef NO_PTHREADS
1079static void *threaded_second_pass(void *data)
1080{
1081        set_thread_data(data);
1082        for (;;) {
1083                int i;
1084                counter_lock();
1085                display_progress(progress, nr_resolved_deltas);
1086                counter_unlock();
1087                work_lock();
1088                while (nr_dispatched < nr_objects &&
1089                       is_delta_type(objects[nr_dispatched].type))
1090                        nr_dispatched++;
1091                if (nr_dispatched >= nr_objects) {
1092                        work_unlock();
1093                        break;
1094                }
1095                i = nr_dispatched++;
1096                work_unlock();
1097
1098                resolve_base(&objects[i]);
1099        }
1100        return NULL;
1101}
1102#endif
1103
1104/*
1105 * First pass:
1106 * - find locations of all objects;
1107 * - calculate SHA1 of all non-delta objects;
1108 * - remember base (SHA1 or offset) for all deltas.
1109 */
1110static void parse_pack_objects(unsigned char *sha1)
1111{
1112        int i, nr_delays = 0;
1113        struct ofs_delta_entry *ofs_delta = ofs_deltas;
1114        unsigned char ref_delta_sha1[20];
1115        struct stat st;
1116
1117        if (verbose)
1118                progress = start_progress(
1119                                from_stdin ? _("Receiving objects") : _("Indexing objects"),
1120                                nr_objects);
1121        for (i = 0; i < nr_objects; i++) {
1122                struct object_entry *obj = &objects[i];
1123                void *data = unpack_raw_entry(obj, &ofs_delta->offset,
1124                                              ref_delta_sha1, obj->idx.sha1);
1125                obj->real_type = obj->type;
1126                if (obj->type == OBJ_OFS_DELTA) {
1127                        nr_ofs_deltas++;
1128                        ofs_delta->obj_no = i;
1129                        ofs_delta++;
1130                } else if (obj->type == OBJ_REF_DELTA) {
1131                        ALLOC_GROW(ref_deltas, nr_ref_deltas + 1, ref_deltas_alloc);
1132                        hashcpy(ref_deltas[nr_ref_deltas].sha1, ref_delta_sha1);
1133                        ref_deltas[nr_ref_deltas].obj_no = i;
1134                        nr_ref_deltas++;
1135                } else if (!data) {
1136                        /* large blobs, check later */
1137                        obj->real_type = OBJ_BAD;
1138                        nr_delays++;
1139                } else
1140                        sha1_object(data, NULL, obj->size, obj->type, obj->idx.sha1);
1141                free(data);
1142                display_progress(progress, i+1);
1143        }
1144        objects[i].idx.offset = consumed_bytes;
1145        stop_progress(&progress);
1146
1147        /* Check pack integrity */
1148        flush();
1149        git_SHA1_Final(sha1, &input_ctx);
1150        if (hashcmp(fill(20), sha1))
1151                die(_("pack is corrupted (SHA1 mismatch)"));
1152        use(20);
1153
1154        /* If input_fd is a file, we should have reached its end now. */
1155        if (fstat(input_fd, &st))
1156                die_errno(_("cannot fstat packfile"));
1157        if (S_ISREG(st.st_mode) &&
1158                        lseek(input_fd, 0, SEEK_CUR) - input_len != st.st_size)
1159                die(_("pack has junk at the end"));
1160
1161        for (i = 0; i < nr_objects; i++) {
1162                struct object_entry *obj = &objects[i];
1163                if (obj->real_type != OBJ_BAD)
1164                        continue;
1165                obj->real_type = obj->type;
1166                sha1_object(NULL, obj, obj->size, obj->type, obj->idx.sha1);
1167                nr_delays--;
1168        }
1169        if (nr_delays)
1170                die(_("confusion beyond insanity in parse_pack_objects()"));
1171}
1172
1173/*
1174 * Second pass:
1175 * - for all non-delta objects, look if it is used as a base for
1176 *   deltas;
1177 * - if used as a base, uncompress the object and apply all deltas,
1178 *   recursively checking if the resulting object is used as a base
1179 *   for some more deltas.
1180 */
1181static void resolve_deltas(void)
1182{
1183        int i;
1184
1185        if (!nr_ofs_deltas && !nr_ref_deltas)
1186                return;
1187
1188        /* Sort deltas by base SHA1/offset for fast searching */
1189        qsort(ofs_deltas, nr_ofs_deltas, sizeof(struct ofs_delta_entry),
1190              compare_ofs_delta_entry);
1191        qsort(ref_deltas, nr_ref_deltas, sizeof(struct ref_delta_entry),
1192              compare_ref_delta_entry);
1193
1194        if (verbose)
1195                progress = start_progress(_("Resolving deltas"),
1196                                          nr_ref_deltas + nr_ofs_deltas);
1197
1198#ifndef NO_PTHREADS
1199        nr_dispatched = 0;
1200        if (nr_threads > 1 || getenv("GIT_FORCE_THREADS")) {
1201                init_thread();
1202                for (i = 0; i < nr_threads; i++) {
1203                        int ret = pthread_create(&thread_data[i].thread, NULL,
1204                                                 threaded_second_pass, thread_data + i);
1205                        if (ret)
1206                                die(_("unable to create thread: %s"),
1207                                    strerror(ret));
1208                }
1209                for (i = 0; i < nr_threads; i++)
1210                        pthread_join(thread_data[i].thread, NULL);
1211                cleanup_thread();
1212                return;
1213        }
1214#endif
1215
1216        for (i = 0; i < nr_objects; i++) {
1217                struct object_entry *obj = &objects[i];
1218
1219                if (is_delta_type(obj->type))
1220                        continue;
1221                resolve_base(obj);
1222                display_progress(progress, nr_resolved_deltas);
1223        }
1224}
1225
1226/*
1227 * Third pass:
1228 * - append objects to convert thin pack to full pack if required
1229 * - write the final 20-byte SHA-1
1230 */
1231static void fix_unresolved_deltas(struct sha1file *f);
1232static void conclude_pack(int fix_thin_pack, const char *curr_pack, unsigned char *pack_sha1)
1233{
1234        if (nr_ref_deltas + nr_ofs_deltas == nr_resolved_deltas) {
1235                stop_progress(&progress);
1236                /* Flush remaining pack final 20-byte SHA1. */
1237                flush();
1238                return;
1239        }
1240
1241        if (fix_thin_pack) {
1242                struct sha1file *f;
1243                unsigned char read_sha1[20], tail_sha1[20];
1244                struct strbuf msg = STRBUF_INIT;
1245                int nr_unresolved = nr_ofs_deltas + nr_ref_deltas - nr_resolved_deltas;
1246                int nr_objects_initial = nr_objects;
1247                if (nr_unresolved <= 0)
1248                        die(_("confusion beyond insanity"));
1249                REALLOC_ARRAY(objects, nr_objects + nr_unresolved + 1);
1250                memset(objects + nr_objects + 1, 0,
1251                       nr_unresolved * sizeof(*objects));
1252                f = sha1fd(output_fd, curr_pack);
1253                fix_unresolved_deltas(f);
1254                strbuf_addf(&msg, Q_("completed with %d local object",
1255                                     "completed with %d local objects",
1256                                     nr_objects - nr_objects_initial),
1257                            nr_objects - nr_objects_initial);
1258                stop_progress_msg(&progress, msg.buf);
1259                strbuf_release(&msg);
1260                sha1close(f, tail_sha1, 0);
1261                hashcpy(read_sha1, pack_sha1);
1262                fixup_pack_header_footer(output_fd, pack_sha1,
1263                                         curr_pack, nr_objects,
1264                                         read_sha1, consumed_bytes-20);
1265                if (hashcmp(read_sha1, tail_sha1) != 0)
1266                        die(_("Unexpected tail checksum for %s "
1267                              "(disk corruption?)"), curr_pack);
1268        }
1269        if (nr_ofs_deltas + nr_ref_deltas != nr_resolved_deltas)
1270                die(Q_("pack has %d unresolved delta",
1271                       "pack has %d unresolved deltas",
1272                       nr_ofs_deltas + nr_ref_deltas - nr_resolved_deltas),
1273                    nr_ofs_deltas + nr_ref_deltas - nr_resolved_deltas);
1274}
1275
1276static int write_compressed(struct sha1file *f, void *in, unsigned int size)
1277{
1278        git_zstream stream;
1279        int status;
1280        unsigned char outbuf[4096];
1281
1282        git_deflate_init(&stream, zlib_compression_level);
1283        stream.next_in = in;
1284        stream.avail_in = size;
1285
1286        do {
1287                stream.next_out = outbuf;
1288                stream.avail_out = sizeof(outbuf);
1289                status = git_deflate(&stream, Z_FINISH);
1290                sha1write(f, outbuf, sizeof(outbuf) - stream.avail_out);
1291        } while (status == Z_OK);
1292
1293        if (status != Z_STREAM_END)
1294                die(_("unable to deflate appended object (%d)"), status);
1295        size = stream.total_out;
1296        git_deflate_end(&stream);
1297        return size;
1298}
1299
1300static struct object_entry *append_obj_to_pack(struct sha1file *f,
1301                               const unsigned char *sha1, void *buf,
1302                               unsigned long size, enum object_type type)
1303{
1304        struct object_entry *obj = &objects[nr_objects++];
1305        unsigned char header[10];
1306        unsigned long s = size;
1307        int n = 0;
1308        unsigned char c = (type << 4) | (s & 15);
1309        s >>= 4;
1310        while (s) {
1311                header[n++] = c | 0x80;
1312                c = s & 0x7f;
1313                s >>= 7;
1314        }
1315        header[n++] = c;
1316        crc32_begin(f);
1317        sha1write(f, header, n);
1318        obj[0].size = size;
1319        obj[0].hdr_size = n;
1320        obj[0].type = type;
1321        obj[0].real_type = type;
1322        obj[1].idx.offset = obj[0].idx.offset + n;
1323        obj[1].idx.offset += write_compressed(f, buf, size);
1324        obj[0].idx.crc32 = crc32_end(f);
1325        sha1flush(f);
1326        hashcpy(obj->idx.sha1, sha1);
1327        return obj;
1328}
1329
1330static int delta_pos_compare(const void *_a, const void *_b)
1331{
1332        struct ref_delta_entry *a = *(struct ref_delta_entry **)_a;
1333        struct ref_delta_entry *b = *(struct ref_delta_entry **)_b;
1334        return a->obj_no - b->obj_no;
1335}
1336
1337static void fix_unresolved_deltas(struct sha1file *f)
1338{
1339        struct ref_delta_entry **sorted_by_pos;
1340        int i;
1341
1342        /*
1343         * Since many unresolved deltas may well be themselves base objects
1344         * for more unresolved deltas, we really want to include the
1345         * smallest number of base objects that would cover as much delta
1346         * as possible by picking the
1347         * trunc deltas first, allowing for other deltas to resolve without
1348         * additional base objects.  Since most base objects are to be found
1349         * before deltas depending on them, a good heuristic is to start
1350         * resolving deltas in the same order as their position in the pack.
1351         */
1352        ALLOC_ARRAY(sorted_by_pos, nr_ref_deltas);
1353        for (i = 0; i < nr_ref_deltas; i++)
1354                sorted_by_pos[i] = &ref_deltas[i];
1355        qsort(sorted_by_pos, nr_ref_deltas, sizeof(*sorted_by_pos), delta_pos_compare);
1356
1357        for (i = 0; i < nr_ref_deltas; i++) {
1358                struct ref_delta_entry *d = sorted_by_pos[i];
1359                enum object_type type;
1360                struct base_data *base_obj = alloc_base_data();
1361
1362                if (objects[d->obj_no].real_type != OBJ_REF_DELTA)
1363                        continue;
1364                base_obj->data = read_sha1_file(d->sha1, &type, &base_obj->size);
1365                if (!base_obj->data)
1366                        continue;
1367
1368                if (check_sha1_signature(d->sha1, base_obj->data,
1369                                base_obj->size, typename(type)))
1370                        die(_("local object %s is corrupt"), sha1_to_hex(d->sha1));
1371                base_obj->obj = append_obj_to_pack(f, d->sha1,
1372                                        base_obj->data, base_obj->size, type);
1373                find_unresolved_deltas(base_obj);
1374                display_progress(progress, nr_resolved_deltas);
1375        }
1376        free(sorted_by_pos);
1377}
1378
1379static void final(const char *final_pack_name, const char *curr_pack_name,
1380                  const char *final_index_name, const char *curr_index_name,
1381                  const char *keep_name, const char *keep_msg,
1382                  unsigned char *sha1)
1383{
1384        const char *report = "pack";
1385        char name[PATH_MAX];
1386        int err;
1387
1388        if (!from_stdin) {
1389                close(input_fd);
1390        } else {
1391                fsync_or_die(output_fd, curr_pack_name);
1392                err = close(output_fd);
1393                if (err)
1394                        die_errno(_("error while closing pack file"));
1395        }
1396
1397        if (keep_msg) {
1398                int keep_fd, keep_msg_len = strlen(keep_msg);
1399
1400                if (!keep_name)
1401                        keep_fd = odb_pack_keep(name, sizeof(name), sha1);
1402                else
1403                        keep_fd = open(keep_name, O_RDWR|O_CREAT|O_EXCL, 0600);
1404
1405                if (keep_fd < 0) {
1406                        if (errno != EEXIST)
1407                                die_errno(_("cannot write keep file '%s'"),
1408                                          keep_name ? keep_name : name);
1409                } else {
1410                        if (keep_msg_len > 0) {
1411                                write_or_die(keep_fd, keep_msg, keep_msg_len);
1412                                write_or_die(keep_fd, "\n", 1);
1413                        }
1414                        if (close(keep_fd) != 0)
1415                                die_errno(_("cannot close written keep file '%s'"),
1416                                          keep_name ? keep_name : name);
1417                        report = "keep";
1418                }
1419        }
1420
1421        if (final_pack_name != curr_pack_name) {
1422                if (!final_pack_name) {
1423                        snprintf(name, sizeof(name), "%s/pack/pack-%s.pack",
1424                                 get_object_directory(), sha1_to_hex(sha1));
1425                        final_pack_name = name;
1426                }
1427                if (finalize_object_file(curr_pack_name, final_pack_name))
1428                        die(_("cannot store pack file"));
1429        } else if (from_stdin)
1430                chmod(final_pack_name, 0444);
1431
1432        if (final_index_name != curr_index_name) {
1433                if (!final_index_name) {
1434                        snprintf(name, sizeof(name), "%s/pack/pack-%s.idx",
1435                                 get_object_directory(), sha1_to_hex(sha1));
1436                        final_index_name = name;
1437                }
1438                if (finalize_object_file(curr_index_name, final_index_name))
1439                        die(_("cannot store index file"));
1440        } else
1441                chmod(final_index_name, 0444);
1442
1443        if (!from_stdin) {
1444                printf("%s\n", sha1_to_hex(sha1));
1445        } else {
1446                char buf[48];
1447                int len = snprintf(buf, sizeof(buf), "%s\t%s\n",
1448                                   report, sha1_to_hex(sha1));
1449                write_or_die(1, buf, len);
1450
1451                /*
1452                 * Let's just mimic git-unpack-objects here and write
1453                 * the last part of the input buffer to stdout.
1454                 */
1455                while (input_len) {
1456                        err = xwrite(1, input_buffer + input_offset, input_len);
1457                        if (err <= 0)
1458                                break;
1459                        input_len -= err;
1460                        input_offset += err;
1461                }
1462        }
1463}
1464
1465static int git_index_pack_config(const char *k, const char *v, void *cb)
1466{
1467        struct pack_idx_option *opts = cb;
1468
1469        if (!strcmp(k, "pack.indexversion")) {
1470                opts->version = git_config_int(k, v);
1471                if (opts->version > 2)
1472                        die(_("bad pack.indexversion=%"PRIu32), opts->version);
1473                return 0;
1474        }
1475        if (!strcmp(k, "pack.threads")) {
1476                nr_threads = git_config_int(k, v);
1477                if (nr_threads < 0)
1478                        die(_("invalid number of threads specified (%d)"),
1479                            nr_threads);
1480#ifdef NO_PTHREADS
1481                if (nr_threads != 1)
1482                        warning(_("no threads support, ignoring %s"), k);
1483                nr_threads = 1;
1484#endif
1485                return 0;
1486        }
1487        return git_default_config(k, v, cb);
1488}
1489
1490static int cmp_uint32(const void *a_, const void *b_)
1491{
1492        uint32_t a = *((uint32_t *)a_);
1493        uint32_t b = *((uint32_t *)b_);
1494
1495        return (a < b) ? -1 : (a != b);
1496}
1497
1498static void read_v2_anomalous_offsets(struct packed_git *p,
1499                                      struct pack_idx_option *opts)
1500{
1501        const uint32_t *idx1, *idx2;
1502        uint32_t i;
1503
1504        /* The address of the 4-byte offset table */
1505        idx1 = (((const uint32_t *)p->index_data)
1506                + 2 /* 8-byte header */
1507                + 256 /* fan out */
1508                + 5 * p->num_objects /* 20-byte SHA-1 table */
1509                + p->num_objects /* CRC32 table */
1510                );
1511
1512        /* The address of the 8-byte offset table */
1513        idx2 = idx1 + p->num_objects;
1514
1515        for (i = 0; i < p->num_objects; i++) {
1516                uint32_t off = ntohl(idx1[i]);
1517                if (!(off & 0x80000000))
1518                        continue;
1519                off = off & 0x7fffffff;
1520                check_pack_index_ptr(p, &idx2[off * 2]);
1521                if (idx2[off * 2])
1522                        continue;
1523                /*
1524                 * The real offset is ntohl(idx2[off * 2]) in high 4
1525                 * octets, and ntohl(idx2[off * 2 + 1]) in low 4
1526                 * octets.  But idx2[off * 2] is Zero!!!
1527                 */
1528                ALLOC_GROW(opts->anomaly, opts->anomaly_nr + 1, opts->anomaly_alloc);
1529                opts->anomaly[opts->anomaly_nr++] = ntohl(idx2[off * 2 + 1]);
1530        }
1531
1532        if (1 < opts->anomaly_nr)
1533                qsort(opts->anomaly, opts->anomaly_nr, sizeof(uint32_t), cmp_uint32);
1534}
1535
1536static void read_idx_option(struct pack_idx_option *opts, const char *pack_name)
1537{
1538        struct packed_git *p = add_packed_git(pack_name, strlen(pack_name), 1);
1539
1540        if (!p)
1541                die(_("Cannot open existing pack file '%s'"), pack_name);
1542        if (open_pack_index(p))
1543                die(_("Cannot open existing pack idx file for '%s'"), pack_name);
1544
1545        /* Read the attributes from the existing idx file */
1546        opts->version = p->index_version;
1547
1548        if (opts->version == 2)
1549                read_v2_anomalous_offsets(p, opts);
1550
1551        /*
1552         * Get rid of the idx file as we do not need it anymore.
1553         * NEEDSWORK: extract this bit from free_pack_by_name() in
1554         * sha1_file.c, perhaps?  It shouldn't matter very much as we
1555         * know we haven't installed this pack (hence we never have
1556         * read anything from it).
1557         */
1558        close_pack_index(p);
1559        free(p);
1560}
1561
1562static void show_pack_info(int stat_only)
1563{
1564        int i, baseobjects = nr_objects - nr_ref_deltas - nr_ofs_deltas;
1565        unsigned long *chain_histogram = NULL;
1566
1567        if (deepest_delta)
1568                chain_histogram = xcalloc(deepest_delta, sizeof(unsigned long));
1569
1570        for (i = 0; i < nr_objects; i++) {
1571                struct object_entry *obj = &objects[i];
1572
1573                if (is_delta_type(obj->type))
1574                        chain_histogram[obj_stat[i].delta_depth - 1]++;
1575                if (stat_only)
1576                        continue;
1577                printf("%s %-6s %lu %lu %"PRIuMAX,
1578                       sha1_to_hex(obj->idx.sha1),
1579                       typename(obj->real_type), obj->size,
1580                       (unsigned long)(obj[1].idx.offset - obj->idx.offset),
1581                       (uintmax_t)obj->idx.offset);
1582                if (is_delta_type(obj->type)) {
1583                        struct object_entry *bobj = &objects[obj_stat[i].base_object_no];
1584                        printf(" %u %s", obj_stat[i].delta_depth, sha1_to_hex(bobj->idx.sha1));
1585                }
1586                putchar('\n');
1587        }
1588
1589        if (baseobjects)
1590                printf_ln(Q_("non delta: %d object",
1591                             "non delta: %d objects",
1592                             baseobjects),
1593                          baseobjects);
1594        for (i = 0; i < deepest_delta; i++) {
1595                if (!chain_histogram[i])
1596                        continue;
1597                printf_ln(Q_("chain length = %d: %lu object",
1598                             "chain length = %d: %lu objects",
1599                             chain_histogram[i]),
1600                          i + 1,
1601                          chain_histogram[i]);
1602        }
1603}
1604
1605static const char *derive_filename(const char *pack_name, const char *suffix,
1606                                   struct strbuf *buf)
1607{
1608        size_t len;
1609        if (!strip_suffix(pack_name, ".pack", &len))
1610                die(_("packfile name '%s' does not end with '.pack'"),
1611                    pack_name);
1612        strbuf_add(buf, pack_name, len);
1613        strbuf_addstr(buf, suffix);
1614        return buf->buf;
1615}
1616
1617int cmd_index_pack(int argc, const char **argv, const char *prefix)
1618{
1619        int i, fix_thin_pack = 0, verify = 0, stat_only = 0;
1620        const char *curr_index;
1621        const char *index_name = NULL, *pack_name = NULL;
1622        const char *keep_name = NULL, *keep_msg = NULL;
1623        struct strbuf index_name_buf = STRBUF_INIT,
1624                      keep_name_buf = STRBUF_INIT;
1625        struct pack_idx_entry **idx_objects;
1626        struct pack_idx_option opts;
1627        unsigned char pack_sha1[20];
1628        unsigned foreign_nr = 1;        /* zero is a "good" value, assume bad */
1629
1630        if (argc == 2 && !strcmp(argv[1], "-h"))
1631                usage(index_pack_usage);
1632
1633        check_replace_refs = 0;
1634        fsck_options.walk = mark_link;
1635
1636        reset_pack_idx_option(&opts);
1637        git_config(git_index_pack_config, &opts);
1638        if (prefix && chdir(prefix))
1639                die(_("Cannot come back to cwd"));
1640
1641        for (i = 1; i < argc; i++) {
1642                const char *arg = argv[i];
1643
1644                if (*arg == '-') {
1645                        if (!strcmp(arg, "--stdin")) {
1646                                from_stdin = 1;
1647                        } else if (!strcmp(arg, "--fix-thin")) {
1648                                fix_thin_pack = 1;
1649                        } else if (!strcmp(arg, "--strict")) {
1650                                strict = 1;
1651                                do_fsck_object = 1;
1652                        } else if (skip_prefix(arg, "--strict=", &arg)) {
1653                                strict = 1;
1654                                do_fsck_object = 1;
1655                                fsck_set_msg_types(&fsck_options, arg);
1656                        } else if (!strcmp(arg, "--check-self-contained-and-connected")) {
1657                                strict = 1;
1658                                check_self_contained_and_connected = 1;
1659                        } else if (!strcmp(arg, "--verify")) {
1660                                verify = 1;
1661                        } else if (!strcmp(arg, "--verify-stat")) {
1662                                verify = 1;
1663                                show_stat = 1;
1664                        } else if (!strcmp(arg, "--verify-stat-only")) {
1665                                verify = 1;
1666                                show_stat = 1;
1667                                stat_only = 1;
1668                        } else if (!strcmp(arg, "--keep")) {
1669                                keep_msg = "";
1670                        } else if (starts_with(arg, "--keep=")) {
1671                                keep_msg = arg + 7;
1672                        } else if (starts_with(arg, "--threads=")) {
1673                                char *end;
1674                                nr_threads = strtoul(arg+10, &end, 0);
1675                                if (!arg[10] || *end || nr_threads < 0)
1676                                        usage(index_pack_usage);
1677#ifdef NO_PTHREADS
1678                                if (nr_threads != 1)
1679                                        warning(_("no threads support, "
1680                                                  "ignoring %s"), arg);
1681                                nr_threads = 1;
1682#endif
1683                        } else if (starts_with(arg, "--pack_header=")) {
1684                                struct pack_header *hdr;
1685                                char *c;
1686
1687                                hdr = (struct pack_header *)input_buffer;
1688                                hdr->hdr_signature = htonl(PACK_SIGNATURE);
1689                                hdr->hdr_version = htonl(strtoul(arg + 14, &c, 10));
1690                                if (*c != ',')
1691                                        die(_("bad %s"), arg);
1692                                hdr->hdr_entries = htonl(strtoul(c + 1, &c, 10));
1693                                if (*c)
1694                                        die(_("bad %s"), arg);
1695                                input_len = sizeof(*hdr);
1696                        } else if (!strcmp(arg, "-v")) {
1697                                verbose = 1;
1698                        } else if (!strcmp(arg, "-o")) {
1699                                if (index_name || (i+1) >= argc)
1700                                        usage(index_pack_usage);
1701                                index_name = argv[++i];
1702                        } else if (starts_with(arg, "--index-version=")) {
1703                                char *c;
1704                                opts.version = strtoul(arg + 16, &c, 10);
1705                                if (opts.version > 2)
1706                                        die(_("bad %s"), arg);
1707                                if (*c == ',')
1708                                        opts.off32_limit = strtoul(c+1, &c, 0);
1709                                if (*c || opts.off32_limit & 0x80000000)
1710                                        die(_("bad %s"), arg);
1711                        } else
1712                                usage(index_pack_usage);
1713                        continue;
1714                }
1715
1716                if (pack_name)
1717                        usage(index_pack_usage);
1718                pack_name = arg;
1719        }
1720
1721        if (!pack_name && !from_stdin)
1722                usage(index_pack_usage);
1723        if (fix_thin_pack && !from_stdin)
1724                die(_("--fix-thin cannot be used without --stdin"));
1725        if (!index_name && pack_name)
1726                index_name = derive_filename(pack_name, ".idx", &index_name_buf);
1727        if (keep_msg && !keep_name && pack_name)
1728                keep_name = derive_filename(pack_name, ".keep", &keep_name_buf);
1729
1730        if (verify) {
1731                if (!index_name)
1732                        die(_("--verify with no packfile name given"));
1733                read_idx_option(&opts, index_name);
1734                opts.flags |= WRITE_IDX_VERIFY | WRITE_IDX_STRICT;
1735        }
1736        if (strict)
1737                opts.flags |= WRITE_IDX_STRICT;
1738
1739#ifndef NO_PTHREADS
1740        if (!nr_threads) {
1741                nr_threads = online_cpus();
1742                /* An experiment showed that more threads does not mean faster */
1743                if (nr_threads > 3)
1744                        nr_threads = 3;
1745        }
1746#endif
1747
1748        curr_pack = open_pack_file(pack_name);
1749        parse_pack_header();
1750        objects = xcalloc(st_add(nr_objects, 1), sizeof(struct object_entry));
1751        if (show_stat)
1752                obj_stat = xcalloc(st_add(nr_objects, 1), sizeof(struct object_stat));
1753        ofs_deltas = xcalloc(nr_objects, sizeof(struct ofs_delta_entry));
1754        parse_pack_objects(pack_sha1);
1755        resolve_deltas();
1756        conclude_pack(fix_thin_pack, curr_pack, pack_sha1);
1757        free(ofs_deltas);
1758        free(ref_deltas);
1759        if (strict)
1760                foreign_nr = check_objects();
1761
1762        if (show_stat)
1763                show_pack_info(stat_only);
1764
1765        ALLOC_ARRAY(idx_objects, nr_objects);
1766        for (i = 0; i < nr_objects; i++)
1767                idx_objects[i] = &objects[i].idx;
1768        curr_index = write_idx_file(index_name, idx_objects, nr_objects, &opts, pack_sha1);
1769        free(idx_objects);
1770
1771        if (!verify)
1772                final(pack_name, curr_pack,
1773                      index_name, curr_index,
1774                      keep_name, keep_msg,
1775                      pack_sha1);
1776        else
1777                close(input_fd);
1778        free(objects);
1779        strbuf_release(&index_name_buf);
1780        strbuf_release(&keep_name_buf);
1781        if (pack_name == NULL)
1782                free((void *) curr_pack);
1783        if (index_name == NULL)
1784                free((void *) curr_index);
1785
1786        /*
1787         * Let the caller know this pack is not self contained
1788         */
1789        if (check_self_contained_and_connected && foreign_nr)
1790                return 1;
1791
1792        return 0;
1793}