builtin / index-pack.con commit Merge branch 'jc/rev-list-simplify-merges-first-parent' (331512f)
   1#include "builtin.h"
   2#include "delta.h"
   3#include "pack.h"
   4#include "csum-file.h"
   5#include "blob.h"
   6#include "commit.h"
   7#include "tag.h"
   8#include "tree.h"
   9#include "progress.h"
  10#include "fsck.h"
  11#include "exec_cmd.h"
  12#include "streaming.h"
  13#include "thread-utils.h"
  14
  15static const char index_pack_usage[] =
  16"git index-pack [-v] [-o <index-file>] [--keep | --keep=<msg>] [--verify] [--strict] (<pack-file> | --stdin [--fix-thin] [<pack-file>])";
  17
  18struct object_entry {
  19        struct pack_idx_entry idx;
  20        unsigned long size;
  21        unsigned int hdr_size;
  22        enum object_type type;
  23        enum object_type real_type;
  24        unsigned delta_depth;
  25        int base_object_no;
  26};
  27
  28union delta_base {
  29        unsigned char sha1[20];
  30        off_t offset;
  31};
  32
  33struct base_data {
  34        struct base_data *base;
  35        struct base_data *child;
  36        struct object_entry *obj;
  37        void *data;
  38        unsigned long size;
  39        int ref_first, ref_last;
  40        int ofs_first, ofs_last;
  41};
  42
  43#if !defined(NO_PTHREADS) && defined(NO_PREAD)
  44/* NO_PREAD uses compat/pread.c, which is not thread-safe. Disable threading. */
  45#define NO_PTHREADS
  46#endif
  47
  48struct thread_local {
  49#ifndef NO_PTHREADS
  50        pthread_t thread;
  51#endif
  52        struct base_data *base_cache;
  53        size_t base_cache_used;
  54};
  55
  56/*
  57 * Even if sizeof(union delta_base) == 24 on 64-bit archs, we really want
  58 * to memcmp() only the first 20 bytes.
  59 */
  60#define UNION_BASE_SZ   20
  61
  62#define FLAG_LINK (1u<<20)
  63#define FLAG_CHECKED (1u<<21)
  64
  65struct delta_entry {
  66        union delta_base base;
  67        int obj_no;
  68};
  69
  70static struct object_entry *objects;
  71static struct delta_entry *deltas;
  72static struct thread_local nothread_data;
  73static int nr_objects;
  74static int nr_deltas;
  75static int nr_resolved_deltas;
  76static int nr_threads;
  77
  78static int from_stdin;
  79static int strict;
  80static int verbose;
  81
  82static struct progress *progress;
  83
  84/* We always read in 4kB chunks. */
  85static unsigned char input_buffer[4096];
  86static unsigned int input_offset, input_len;
  87static off_t consumed_bytes;
  88static unsigned deepest_delta;
  89static git_SHA_CTX input_ctx;
  90static uint32_t input_crc32;
  91static int input_fd, output_fd, pack_fd;
  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_key_t key;
 112
 113static inline void lock_mutex(pthread_mutex_t *mutex)
 114{
 115        if (threads_active)
 116                pthread_mutex_lock(mutex);
 117}
 118
 119static inline void unlock_mutex(pthread_mutex_t *mutex)
 120{
 121        if (threads_active)
 122                pthread_mutex_unlock(mutex);
 123}
 124
 125/*
 126 * Mutex and conditional variable can't be statically-initialized on Windows.
 127 */
 128static void init_thread(void)
 129{
 130        init_recursive_mutex(&read_mutex);
 131        pthread_mutex_init(&counter_mutex, NULL);
 132        pthread_mutex_init(&work_mutex, NULL);
 133        pthread_key_create(&key, NULL);
 134        thread_data = xcalloc(nr_threads, sizeof(*thread_data));
 135        threads_active = 1;
 136}
 137
 138static void cleanup_thread(void)
 139{
 140        if (!threads_active)
 141                return;
 142        threads_active = 0;
 143        pthread_mutex_destroy(&read_mutex);
 144        pthread_mutex_destroy(&counter_mutex);
 145        pthread_mutex_destroy(&work_mutex);
 146        pthread_key_delete(key);
 147        free(thread_data);
 148}
 149
 150#else
 151
 152#define read_lock()
 153#define read_unlock()
 154
 155#define counter_lock()
 156#define counter_unlock()
 157
 158#define work_lock()
 159#define work_unlock()
 160
 161#endif
 162
 163
 164static int mark_link(struct object *obj, int type, void *data)
 165{
 166        if (!obj)
 167                return -1;
 168
 169        if (type != OBJ_ANY && obj->type != type)
 170                die(_("object type mismatch at %s"), sha1_to_hex(obj->sha1));
 171
 172        obj->flags |= FLAG_LINK;
 173        return 0;
 174}
 175
 176/* The content of each linked object must have been checked
 177   or it must be already present in the object database */
 178static void check_object(struct object *obj)
 179{
 180        if (!obj)
 181                return;
 182
 183        if (!(obj->flags & FLAG_LINK))
 184                return;
 185
 186        if (!(obj->flags & FLAG_CHECKED)) {
 187                unsigned long size;
 188                int type = sha1_object_info(obj->sha1, &size);
 189                if (type != obj->type || type <= 0)
 190                        die(_("object of unexpected type"));
 191                obj->flags |= FLAG_CHECKED;
 192                return;
 193        }
 194}
 195
 196static void check_objects(void)
 197{
 198        unsigned i, max;
 199
 200        max = get_max_object_index();
 201        for (i = 0; i < max; i++)
 202                check_object(get_indexed_object(i));
 203}
 204
 205
 206/* Discard current buffer used content. */
 207static void flush(void)
 208{
 209        if (input_offset) {
 210                if (output_fd >= 0)
 211                        write_or_die(output_fd, input_buffer, input_offset);
 212                git_SHA1_Update(&input_ctx, input_buffer, input_offset);
 213                memmove(input_buffer, input_buffer + input_offset, input_len);
 214                input_offset = 0;
 215        }
 216}
 217
 218/*
 219 * Make sure at least "min" bytes are available in the buffer, and
 220 * return the pointer to the buffer.
 221 */
 222static void *fill(int min)
 223{
 224        if (min <= input_len)
 225                return input_buffer + input_offset;
 226        if (min > sizeof(input_buffer))
 227                die(Q_("cannot fill %d byte",
 228                       "cannot fill %d bytes",
 229                       min),
 230                    min);
 231        flush();
 232        do {
 233                ssize_t ret = xread(input_fd, input_buffer + input_len,
 234                                sizeof(input_buffer) - input_len);
 235                if (ret <= 0) {
 236                        if (!ret)
 237                                die(_("early EOF"));
 238                        die_errno(_("read error on input"));
 239                }
 240                input_len += ret;
 241                if (from_stdin)
 242                        display_throughput(progress, consumed_bytes + input_len);
 243        } while (input_len < min);
 244        return input_buffer;
 245}
 246
 247static void use(int bytes)
 248{
 249        if (bytes > input_len)
 250                die(_("used more bytes than were available"));
 251        input_crc32 = crc32(input_crc32, input_buffer + input_offset, bytes);
 252        input_len -= bytes;
 253        input_offset += bytes;
 254
 255        /* make sure off_t is sufficiently large not to wrap */
 256        if (signed_add_overflows(consumed_bytes, bytes))
 257                die(_("pack too large for current definition of off_t"));
 258        consumed_bytes += bytes;
 259}
 260
 261static const char *open_pack_file(const char *pack_name)
 262{
 263        if (from_stdin) {
 264                input_fd = 0;
 265                if (!pack_name) {
 266                        static char tmp_file[PATH_MAX];
 267                        output_fd = odb_mkstemp(tmp_file, sizeof(tmp_file),
 268                                                "pack/tmp_pack_XXXXXX");
 269                        pack_name = xstrdup(tmp_file);
 270                } else
 271                        output_fd = open(pack_name, O_CREAT|O_EXCL|O_RDWR, 0600);
 272                if (output_fd < 0)
 273                        die_errno(_("unable to create '%s'"), pack_name);
 274                pack_fd = output_fd;
 275        } else {
 276                input_fd = open(pack_name, O_RDONLY);
 277                if (input_fd < 0)
 278                        die_errno(_("cannot open packfile '%s'"), pack_name);
 279                output_fd = -1;
 280                pack_fd = input_fd;
 281        }
 282        git_SHA1_Init(&input_ctx);
 283        return pack_name;
 284}
 285
 286static void parse_pack_header(void)
 287{
 288        struct pack_header *hdr = fill(sizeof(struct pack_header));
 289
 290        /* Header consistency check */
 291        if (hdr->hdr_signature != htonl(PACK_SIGNATURE))
 292                die(_("pack signature mismatch"));
 293        if (!pack_version_ok(hdr->hdr_version))
 294                die("pack version %"PRIu32" unsupported",
 295                        ntohl(hdr->hdr_version));
 296
 297        nr_objects = ntohl(hdr->hdr_entries);
 298        use(sizeof(struct pack_header));
 299}
 300
 301static NORETURN void bad_object(unsigned long offset, const char *format,
 302                       ...) __attribute__((format (printf, 2, 3)));
 303
 304static NORETURN void bad_object(unsigned long offset, const char *format, ...)
 305{
 306        va_list params;
 307        char buf[1024];
 308
 309        va_start(params, format);
 310        vsnprintf(buf, sizeof(buf), format, params);
 311        va_end(params);
 312        die(_("pack has bad object at offset %lu: %s"), offset, buf);
 313}
 314
 315static inline struct thread_local *get_thread_data(void)
 316{
 317#ifndef NO_PTHREADS
 318        if (threads_active)
 319                return pthread_getspecific(key);
 320        assert(!threads_active &&
 321               "This should only be reached when all threads are gone");
 322#endif
 323        return &nothread_data;
 324}
 325
 326#ifndef NO_PTHREADS
 327static void set_thread_data(struct thread_local *data)
 328{
 329        if (threads_active)
 330                pthread_setspecific(key, data);
 331}
 332#endif
 333
 334static struct base_data *alloc_base_data(void)
 335{
 336        struct base_data *base = xmalloc(sizeof(struct base_data));
 337        memset(base, 0, sizeof(*base));
 338        base->ref_last = -1;
 339        base->ofs_last = -1;
 340        return base;
 341}
 342
 343static void free_base_data(struct base_data *c)
 344{
 345        if (c->data) {
 346                free(c->data);
 347                c->data = NULL;
 348                get_thread_data()->base_cache_used -= c->size;
 349        }
 350}
 351
 352static void prune_base_data(struct base_data *retain)
 353{
 354        struct base_data *b;
 355        struct thread_local *data = get_thread_data();
 356        for (b = data->base_cache;
 357             data->base_cache_used > delta_base_cache_limit && b;
 358             b = b->child) {
 359                if (b->data && b != retain)
 360                        free_base_data(b);
 361        }
 362}
 363
 364static void link_base_data(struct base_data *base, struct base_data *c)
 365{
 366        if (base)
 367                base->child = c;
 368        else
 369                get_thread_data()->base_cache = c;
 370
 371        c->base = base;
 372        c->child = NULL;
 373        if (c->data)
 374                get_thread_data()->base_cache_used += c->size;
 375        prune_base_data(c);
 376}
 377
 378static void unlink_base_data(struct base_data *c)
 379{
 380        struct base_data *base = c->base;
 381        if (base)
 382                base->child = NULL;
 383        else
 384                get_thread_data()->base_cache = NULL;
 385        free_base_data(c);
 386}
 387
 388static int is_delta_type(enum object_type type)
 389{
 390        return (type == OBJ_REF_DELTA || type == OBJ_OFS_DELTA);
 391}
 392
 393static void *unpack_entry_data(unsigned long offset, unsigned long size,
 394                               enum object_type type, unsigned char *sha1)
 395{
 396        static char fixed_buf[8192];
 397        int status;
 398        git_zstream stream;
 399        void *buf;
 400        git_SHA_CTX c;
 401        char hdr[32];
 402        int hdrlen;
 403
 404        if (!is_delta_type(type)) {
 405                hdrlen = sprintf(hdr, "%s %lu", typename(type), size) + 1;
 406                git_SHA1_Init(&c);
 407                git_SHA1_Update(&c, hdr, hdrlen);
 408        } else
 409                sha1 = NULL;
 410        if (type == OBJ_BLOB && size > big_file_threshold)
 411                buf = fixed_buf;
 412        else
 413                buf = xmalloc(size);
 414
 415        memset(&stream, 0, sizeof(stream));
 416        git_inflate_init(&stream);
 417        stream.next_out = buf;
 418        stream.avail_out = buf == fixed_buf ? sizeof(fixed_buf) : size;
 419
 420        do {
 421                unsigned char *last_out = stream.next_out;
 422                stream.next_in = fill(1);
 423                stream.avail_in = input_len;
 424                status = git_inflate(&stream, 0);
 425                use(input_len - stream.avail_in);
 426                if (sha1)
 427                        git_SHA1_Update(&c, last_out, stream.next_out - last_out);
 428                if (buf == fixed_buf) {
 429                        stream.next_out = buf;
 430                        stream.avail_out = sizeof(fixed_buf);
 431                }
 432        } while (status == Z_OK);
 433        if (stream.total_out != size || status != Z_STREAM_END)
 434                bad_object(offset, _("inflate returned %d"), status);
 435        git_inflate_end(&stream);
 436        if (sha1)
 437                git_SHA1_Final(sha1, &c);
 438        return buf == fixed_buf ? NULL : buf;
 439}
 440
 441static void *unpack_raw_entry(struct object_entry *obj,
 442                              union delta_base *delta_base,
 443                              unsigned char *sha1)
 444{
 445        unsigned char *p;
 446        unsigned long size, c;
 447        off_t base_offset;
 448        unsigned shift;
 449        void *data;
 450
 451        obj->idx.offset = consumed_bytes;
 452        input_crc32 = crc32(0, NULL, 0);
 453
 454        p = fill(1);
 455        c = *p;
 456        use(1);
 457        obj->type = (c >> 4) & 7;
 458        size = (c & 15);
 459        shift = 4;
 460        while (c & 0x80) {
 461                p = fill(1);
 462                c = *p;
 463                use(1);
 464                size += (c & 0x7f) << shift;
 465                shift += 7;
 466        }
 467        obj->size = size;
 468
 469        switch (obj->type) {
 470        case OBJ_REF_DELTA:
 471                hashcpy(delta_base->sha1, fill(20));
 472                use(20);
 473                break;
 474        case OBJ_OFS_DELTA:
 475                memset(delta_base, 0, sizeof(*delta_base));
 476                p = fill(1);
 477                c = *p;
 478                use(1);
 479                base_offset = c & 127;
 480                while (c & 128) {
 481                        base_offset += 1;
 482                        if (!base_offset || MSB(base_offset, 7))
 483                                bad_object(obj->idx.offset, _("offset value overflow for delta base object"));
 484                        p = fill(1);
 485                        c = *p;
 486                        use(1);
 487                        base_offset = (base_offset << 7) + (c & 127);
 488                }
 489                delta_base->offset = obj->idx.offset - base_offset;
 490                if (delta_base->offset <= 0 || delta_base->offset >= obj->idx.offset)
 491                        bad_object(obj->idx.offset, _("delta base offset is out of bound"));
 492                break;
 493        case OBJ_COMMIT:
 494        case OBJ_TREE:
 495        case OBJ_BLOB:
 496        case OBJ_TAG:
 497                break;
 498        default:
 499                bad_object(obj->idx.offset, _("unknown object type %d"), obj->type);
 500        }
 501        obj->hdr_size = consumed_bytes - obj->idx.offset;
 502
 503        data = unpack_entry_data(obj->idx.offset, obj->size, obj->type, sha1);
 504        obj->idx.crc32 = input_crc32;
 505        return data;
 506}
 507
 508static void *unpack_data(struct object_entry *obj,
 509                         int (*consume)(const unsigned char *, unsigned long, void *),
 510                         void *cb_data)
 511{
 512        off_t from = obj[0].idx.offset + obj[0].hdr_size;
 513        unsigned long len = obj[1].idx.offset - from;
 514        unsigned char *data, *inbuf;
 515        git_zstream stream;
 516        int status;
 517
 518        data = xmalloc(consume ? 64*1024 : obj->size);
 519        inbuf = xmalloc((len < 64*1024) ? len : 64*1024);
 520
 521        memset(&stream, 0, sizeof(stream));
 522        git_inflate_init(&stream);
 523        stream.next_out = data;
 524        stream.avail_out = consume ? 64*1024 : obj->size;
 525
 526        do {
 527                unsigned char *last_out = stream.next_out;
 528                ssize_t n = (len < 64*1024) ? len : 64*1024;
 529                n = pread(pack_fd, inbuf, n, from);
 530                if (n < 0)
 531                        die_errno(_("cannot pread pack file"));
 532                if (!n)
 533                        die(Q_("premature end of pack file, %lu byte missing",
 534                               "premature end of pack file, %lu bytes missing",
 535                               len),
 536                            len);
 537                from += n;
 538                len -= n;
 539                stream.next_in = inbuf;
 540                stream.avail_in = n;
 541                status = git_inflate(&stream, 0);
 542                if (consume) {
 543                        if (consume(last_out, stream.next_out - last_out, cb_data)) {
 544                                free(inbuf);
 545                                free(data);
 546                                return NULL;
 547                        }
 548                        stream.next_out = data;
 549                        stream.avail_out = 64*1024;
 550                }
 551        } while (len && status == Z_OK && !stream.avail_in);
 552
 553        /* This has been inflated OK when first encountered, so... */
 554        if (status != Z_STREAM_END || stream.total_out != obj->size)
 555                die(_("serious inflate inconsistency"));
 556
 557        git_inflate_end(&stream);
 558        free(inbuf);
 559        if (consume) {
 560                free(data);
 561                data = NULL;
 562        }
 563        return data;
 564}
 565
 566static void *get_data_from_pack(struct object_entry *obj)
 567{
 568        return unpack_data(obj, NULL, NULL);
 569}
 570
 571static int compare_delta_bases(const union delta_base *base1,
 572                               const union delta_base *base2,
 573                               enum object_type type1,
 574                               enum object_type type2)
 575{
 576        int cmp = type1 - type2;
 577        if (cmp)
 578                return cmp;
 579        return memcmp(base1, base2, UNION_BASE_SZ);
 580}
 581
 582static int find_delta(const union delta_base *base, enum object_type type)
 583{
 584        int first = 0, last = nr_deltas;
 585
 586        while (first < last) {
 587                int next = (first + last) / 2;
 588                struct delta_entry *delta = &deltas[next];
 589                int cmp;
 590
 591                cmp = compare_delta_bases(base, &delta->base,
 592                                          type, objects[delta->obj_no].type);
 593                if (!cmp)
 594                        return next;
 595                if (cmp < 0) {
 596                        last = next;
 597                        continue;
 598                }
 599                first = next+1;
 600        }
 601        return -first-1;
 602}
 603
 604static void find_delta_children(const union delta_base *base,
 605                                int *first_index, int *last_index,
 606                                enum object_type type)
 607{
 608        int first = find_delta(base, type);
 609        int last = first;
 610        int end = nr_deltas - 1;
 611
 612        if (first < 0) {
 613                *first_index = 0;
 614                *last_index = -1;
 615                return;
 616        }
 617        while (first > 0 && !memcmp(&deltas[first - 1].base, base, UNION_BASE_SZ))
 618                --first;
 619        while (last < end && !memcmp(&deltas[last + 1].base, base, UNION_BASE_SZ))
 620                ++last;
 621        *first_index = first;
 622        *last_index = last;
 623}
 624
 625struct compare_data {
 626        struct object_entry *entry;
 627        struct git_istream *st;
 628        unsigned char *buf;
 629        unsigned long buf_size;
 630};
 631
 632static int compare_objects(const unsigned char *buf, unsigned long size,
 633                           void *cb_data)
 634{
 635        struct compare_data *data = cb_data;
 636
 637        if (data->buf_size < size) {
 638                free(data->buf);
 639                data->buf = xmalloc(size);
 640                data->buf_size = size;
 641        }
 642
 643        while (size) {
 644                ssize_t len = read_istream(data->st, data->buf, size);
 645                if (len == 0)
 646                        die(_("SHA1 COLLISION FOUND WITH %s !"),
 647                            sha1_to_hex(data->entry->idx.sha1));
 648                if (len < 0)
 649                        die(_("unable to read %s"),
 650                            sha1_to_hex(data->entry->idx.sha1));
 651                if (memcmp(buf, data->buf, len))
 652                        die(_("SHA1 COLLISION FOUND WITH %s !"),
 653                            sha1_to_hex(data->entry->idx.sha1));
 654                size -= len;
 655                buf += len;
 656        }
 657        return 0;
 658}
 659
 660static int check_collison(struct object_entry *entry)
 661{
 662        struct compare_data data;
 663        enum object_type type;
 664        unsigned long size;
 665
 666        if (entry->size <= big_file_threshold || entry->type != OBJ_BLOB)
 667                return -1;
 668
 669        memset(&data, 0, sizeof(data));
 670        data.entry = entry;
 671        data.st = open_istream(entry->idx.sha1, &type, &size, NULL);
 672        if (!data.st)
 673                return -1;
 674        if (size != entry->size || type != entry->type)
 675                die(_("SHA1 COLLISION FOUND WITH %s !"),
 676                    sha1_to_hex(entry->idx.sha1));
 677        unpack_data(entry, compare_objects, &data);
 678        close_istream(data.st);
 679        free(data.buf);
 680        return 0;
 681}
 682
 683static void sha1_object(const void *data, struct object_entry *obj_entry,
 684                        unsigned long size, enum object_type type,
 685                        const unsigned char *sha1)
 686{
 687        void *new_data = NULL;
 688        int collision_test_needed;
 689
 690        assert(data || obj_entry);
 691
 692        read_lock();
 693        collision_test_needed = has_sha1_file(sha1);
 694        read_unlock();
 695
 696        if (collision_test_needed && !data) {
 697                read_lock();
 698                if (!check_collison(obj_entry))
 699                        collision_test_needed = 0;
 700                read_unlock();
 701        }
 702        if (collision_test_needed) {
 703                void *has_data;
 704                enum object_type has_type;
 705                unsigned long has_size;
 706                read_lock();
 707                has_type = sha1_object_info(sha1, &has_size);
 708                if (has_type != type || has_size != size)
 709                        die(_("SHA1 COLLISION FOUND WITH %s !"), sha1_to_hex(sha1));
 710                has_data = read_sha1_file(sha1, &has_type, &has_size);
 711                read_unlock();
 712                if (!data)
 713                        data = new_data = get_data_from_pack(obj_entry);
 714                if (!has_data)
 715                        die(_("cannot read existing object %s"), sha1_to_hex(sha1));
 716                if (size != has_size || type != has_type ||
 717                    memcmp(data, has_data, size) != 0)
 718                        die(_("SHA1 COLLISION FOUND WITH %s !"), sha1_to_hex(sha1));
 719                free(has_data);
 720        }
 721
 722        if (strict) {
 723                read_lock();
 724                if (type == OBJ_BLOB) {
 725                        struct blob *blob = lookup_blob(sha1);
 726                        if (blob)
 727                                blob->object.flags |= FLAG_CHECKED;
 728                        else
 729                                die(_("invalid blob object %s"), sha1_to_hex(sha1));
 730                } else {
 731                        struct object *obj;
 732                        int eaten;
 733                        void *buf = (void *) data;
 734
 735                        if (!buf)
 736                                buf = new_data = get_data_from_pack(obj_entry);
 737
 738                        /*
 739                         * we do not need to free the memory here, as the
 740                         * buf is deleted by the caller.
 741                         */
 742                        obj = parse_object_buffer(sha1, type, size, buf, &eaten);
 743                        if (!obj)
 744                                die(_("invalid %s"), typename(type));
 745                        if (fsck_object(obj, 1, fsck_error_function))
 746                                die(_("Error in object"));
 747                        if (fsck_walk(obj, mark_link, NULL))
 748                                die(_("Not all child objects of %s are reachable"), sha1_to_hex(obj->sha1));
 749
 750                        if (obj->type == OBJ_TREE) {
 751                                struct tree *item = (struct tree *) obj;
 752                                item->buffer = NULL;
 753                        }
 754                        if (obj->type == OBJ_COMMIT) {
 755                                struct commit *commit = (struct commit *) obj;
 756                                commit->buffer = NULL;
 757                        }
 758                        obj->flags |= FLAG_CHECKED;
 759                }
 760                read_unlock();
 761        }
 762
 763        free(new_data);
 764}
 765
 766/*
 767 * This function is part of find_unresolved_deltas(). There are two
 768 * walkers going in the opposite ways.
 769 *
 770 * The first one in find_unresolved_deltas() traverses down from
 771 * parent node to children, deflating nodes along the way. However,
 772 * memory for deflated nodes is limited by delta_base_cache_limit, so
 773 * at some point parent node's deflated content may be freed.
 774 *
 775 * The second walker is this function, which goes from current node up
 776 * to top parent if necessary to deflate the node. In normal
 777 * situation, its parent node would be already deflated, so it just
 778 * needs to apply delta.
 779 *
 780 * In the worst case scenario, parent node is no longer deflated because
 781 * we're running out of delta_base_cache_limit; we need to re-deflate
 782 * parents, possibly up to the top base.
 783 *
 784 * All deflated objects here are subject to be freed if we exceed
 785 * delta_base_cache_limit, just like in find_unresolved_deltas(), we
 786 * just need to make sure the last node is not freed.
 787 */
 788static void *get_base_data(struct base_data *c)
 789{
 790        if (!c->data) {
 791                struct object_entry *obj = c->obj;
 792                struct base_data **delta = NULL;
 793                int delta_nr = 0, delta_alloc = 0;
 794
 795                while (is_delta_type(c->obj->type) && !c->data) {
 796                        ALLOC_GROW(delta, delta_nr + 1, delta_alloc);
 797                        delta[delta_nr++] = c;
 798                        c = c->base;
 799                }
 800                if (!delta_nr) {
 801                        c->data = get_data_from_pack(obj);
 802                        c->size = obj->size;
 803                        get_thread_data()->base_cache_used += c->size;
 804                        prune_base_data(c);
 805                }
 806                for (; delta_nr > 0; delta_nr--) {
 807                        void *base, *raw;
 808                        c = delta[delta_nr - 1];
 809                        obj = c->obj;
 810                        base = get_base_data(c->base);
 811                        raw = get_data_from_pack(obj);
 812                        c->data = patch_delta(
 813                                base, c->base->size,
 814                                raw, obj->size,
 815                                &c->size);
 816                        free(raw);
 817                        if (!c->data)
 818                                bad_object(obj->idx.offset, _("failed to apply delta"));
 819                        get_thread_data()->base_cache_used += c->size;
 820                        prune_base_data(c);
 821                }
 822                free(delta);
 823        }
 824        return c->data;
 825}
 826
 827static void resolve_delta(struct object_entry *delta_obj,
 828                          struct base_data *base, struct base_data *result)
 829{
 830        void *base_data, *delta_data;
 831
 832        delta_obj->real_type = base->obj->real_type;
 833        delta_obj->delta_depth = base->obj->delta_depth + 1;
 834        if (deepest_delta < delta_obj->delta_depth)
 835                deepest_delta = delta_obj->delta_depth;
 836        delta_obj->base_object_no = base->obj - objects;
 837        delta_data = get_data_from_pack(delta_obj);
 838        base_data = get_base_data(base);
 839        result->obj = delta_obj;
 840        result->data = patch_delta(base_data, base->size,
 841                                   delta_data, delta_obj->size, &result->size);
 842        free(delta_data);
 843        if (!result->data)
 844                bad_object(delta_obj->idx.offset, _("failed to apply delta"));
 845        hash_sha1_file(result->data, result->size,
 846                       typename(delta_obj->real_type), delta_obj->idx.sha1);
 847        sha1_object(result->data, NULL, result->size, delta_obj->real_type,
 848                    delta_obj->idx.sha1);
 849        counter_lock();
 850        nr_resolved_deltas++;
 851        counter_unlock();
 852}
 853
 854static struct base_data *find_unresolved_deltas_1(struct base_data *base,
 855                                                  struct base_data *prev_base)
 856{
 857        if (base->ref_last == -1 && base->ofs_last == -1) {
 858                union delta_base base_spec;
 859
 860                hashcpy(base_spec.sha1, base->obj->idx.sha1);
 861                find_delta_children(&base_spec,
 862                                    &base->ref_first, &base->ref_last, OBJ_REF_DELTA);
 863
 864                memset(&base_spec, 0, sizeof(base_spec));
 865                base_spec.offset = base->obj->idx.offset;
 866                find_delta_children(&base_spec,
 867                                    &base->ofs_first, &base->ofs_last, OBJ_OFS_DELTA);
 868
 869                if (base->ref_last == -1 && base->ofs_last == -1) {
 870                        free(base->data);
 871                        return NULL;
 872                }
 873
 874                link_base_data(prev_base, base);
 875        }
 876
 877        if (base->ref_first <= base->ref_last) {
 878                struct object_entry *child = objects + deltas[base->ref_first].obj_no;
 879                struct base_data *result = alloc_base_data();
 880
 881                assert(child->real_type == OBJ_REF_DELTA);
 882                resolve_delta(child, base, result);
 883                if (base->ref_first == base->ref_last && base->ofs_last == -1)
 884                        free_base_data(base);
 885
 886                base->ref_first++;
 887                return result;
 888        }
 889
 890        if (base->ofs_first <= base->ofs_last) {
 891                struct object_entry *child = objects + deltas[base->ofs_first].obj_no;
 892                struct base_data *result = alloc_base_data();
 893
 894                assert(child->real_type == OBJ_OFS_DELTA);
 895                resolve_delta(child, base, result);
 896                if (base->ofs_first == base->ofs_last)
 897                        free_base_data(base);
 898
 899                base->ofs_first++;
 900                return result;
 901        }
 902
 903        unlink_base_data(base);
 904        return NULL;
 905}
 906
 907static void find_unresolved_deltas(struct base_data *base)
 908{
 909        struct base_data *new_base, *prev_base = NULL;
 910        for (;;) {
 911                new_base = find_unresolved_deltas_1(base, prev_base);
 912
 913                if (new_base) {
 914                        prev_base = base;
 915                        base = new_base;
 916                } else {
 917                        free(base);
 918                        base = prev_base;
 919                        if (!base)
 920                                return;
 921                        prev_base = base->base;
 922                }
 923        }
 924}
 925
 926static int compare_delta_entry(const void *a, const void *b)
 927{
 928        const struct delta_entry *delta_a = a;
 929        const struct delta_entry *delta_b = b;
 930
 931        /* group by type (ref vs ofs) and then by value (sha-1 or offset) */
 932        return compare_delta_bases(&delta_a->base, &delta_b->base,
 933                                   objects[delta_a->obj_no].type,
 934                                   objects[delta_b->obj_no].type);
 935}
 936
 937static void resolve_base(struct object_entry *obj)
 938{
 939        struct base_data *base_obj = alloc_base_data();
 940        base_obj->obj = obj;
 941        base_obj->data = NULL;
 942        find_unresolved_deltas(base_obj);
 943}
 944
 945#ifndef NO_PTHREADS
 946static void *threaded_second_pass(void *data)
 947{
 948        set_thread_data(data);
 949        for (;;) {
 950                int i;
 951                work_lock();
 952                display_progress(progress, nr_resolved_deltas);
 953                while (nr_dispatched < nr_objects &&
 954                       is_delta_type(objects[nr_dispatched].type))
 955                        nr_dispatched++;
 956                if (nr_dispatched >= nr_objects) {
 957                        work_unlock();
 958                        break;
 959                }
 960                i = nr_dispatched++;
 961                work_unlock();
 962
 963                resolve_base(&objects[i]);
 964        }
 965        return NULL;
 966}
 967#endif
 968
 969/*
 970 * First pass:
 971 * - find locations of all objects;
 972 * - calculate SHA1 of all non-delta objects;
 973 * - remember base (SHA1 or offset) for all deltas.
 974 */
 975static void parse_pack_objects(unsigned char *sha1)
 976{
 977        int i, nr_delays = 0;
 978        struct delta_entry *delta = deltas;
 979        struct stat st;
 980
 981        if (verbose)
 982                progress = start_progress(
 983                                from_stdin ? _("Receiving objects") : _("Indexing objects"),
 984                                nr_objects);
 985        for (i = 0; i < nr_objects; i++) {
 986                struct object_entry *obj = &objects[i];
 987                void *data = unpack_raw_entry(obj, &delta->base, obj->idx.sha1);
 988                obj->real_type = obj->type;
 989                if (is_delta_type(obj->type)) {
 990                        nr_deltas++;
 991                        delta->obj_no = i;
 992                        delta++;
 993                } else if (!data) {
 994                        /* large blobs, check later */
 995                        obj->real_type = OBJ_BAD;
 996                        nr_delays++;
 997                } else
 998                        sha1_object(data, NULL, obj->size, obj->type, obj->idx.sha1);
 999                free(data);
1000                display_progress(progress, i+1);
1001        }
1002        objects[i].idx.offset = consumed_bytes;
1003        stop_progress(&progress);
1004
1005        /* Check pack integrity */
1006        flush();
1007        git_SHA1_Final(sha1, &input_ctx);
1008        if (hashcmp(fill(20), sha1))
1009                die(_("pack is corrupted (SHA1 mismatch)"));
1010        use(20);
1011
1012        /* If input_fd is a file, we should have reached its end now. */
1013        if (fstat(input_fd, &st))
1014                die_errno(_("cannot fstat packfile"));
1015        if (S_ISREG(st.st_mode) &&
1016                        lseek(input_fd, 0, SEEK_CUR) - input_len != st.st_size)
1017                die(_("pack has junk at the end"));
1018
1019        for (i = 0; i < nr_objects; i++) {
1020                struct object_entry *obj = &objects[i];
1021                if (obj->real_type != OBJ_BAD)
1022                        continue;
1023                obj->real_type = obj->type;
1024                sha1_object(NULL, obj, obj->size, obj->type, obj->idx.sha1);
1025                nr_delays--;
1026        }
1027        if (nr_delays)
1028                die(_("confusion beyond insanity in parse_pack_objects()"));
1029}
1030
1031/*
1032 * Second pass:
1033 * - for all non-delta objects, look if it is used as a base for
1034 *   deltas;
1035 * - if used as a base, uncompress the object and apply all deltas,
1036 *   recursively checking if the resulting object is used as a base
1037 *   for some more deltas.
1038 */
1039static void resolve_deltas(void)
1040{
1041        int i;
1042
1043        if (!nr_deltas)
1044                return;
1045
1046        /* Sort deltas by base SHA1/offset for fast searching */
1047        qsort(deltas, nr_deltas, sizeof(struct delta_entry),
1048              compare_delta_entry);
1049
1050        if (verbose)
1051                progress = start_progress(_("Resolving deltas"), nr_deltas);
1052
1053#ifndef NO_PTHREADS
1054        nr_dispatched = 0;
1055        if (nr_threads > 1 || getenv("GIT_FORCE_THREADS")) {
1056                init_thread();
1057                for (i = 0; i < nr_threads; i++) {
1058                        int ret = pthread_create(&thread_data[i].thread, NULL,
1059                                                 threaded_second_pass, thread_data + i);
1060                        if (ret)
1061                                die("unable to create thread: %s", strerror(ret));
1062                }
1063                for (i = 0; i < nr_threads; i++)
1064                        pthread_join(thread_data[i].thread, NULL);
1065                cleanup_thread();
1066                return;
1067        }
1068#endif
1069
1070        for (i = 0; i < nr_objects; i++) {
1071                struct object_entry *obj = &objects[i];
1072
1073                if (is_delta_type(obj->type))
1074                        continue;
1075                resolve_base(obj);
1076                display_progress(progress, nr_resolved_deltas);
1077        }
1078}
1079
1080/*
1081 * Third pass:
1082 * - append objects to convert thin pack to full pack if required
1083 * - write the final 20-byte SHA-1
1084 */
1085static void fix_unresolved_deltas(struct sha1file *f, int nr_unresolved);
1086static void conclude_pack(int fix_thin_pack, const char *curr_pack, unsigned char *pack_sha1)
1087{
1088        if (nr_deltas == nr_resolved_deltas) {
1089                stop_progress(&progress);
1090                /* Flush remaining pack final 20-byte SHA1. */
1091                flush();
1092                return;
1093        }
1094
1095        if (fix_thin_pack) {
1096                struct sha1file *f;
1097                unsigned char read_sha1[20], tail_sha1[20];
1098                char msg[48];
1099                int nr_unresolved = nr_deltas - nr_resolved_deltas;
1100                int nr_objects_initial = nr_objects;
1101                if (nr_unresolved <= 0)
1102                        die(_("confusion beyond insanity"));
1103                objects = xrealloc(objects,
1104                                   (nr_objects + nr_unresolved + 1)
1105                                   * sizeof(*objects));
1106                f = sha1fd(output_fd, curr_pack);
1107                fix_unresolved_deltas(f, nr_unresolved);
1108                sprintf(msg, "completed with %d local objects",
1109                        nr_objects - nr_objects_initial);
1110                stop_progress_msg(&progress, msg);
1111                sha1close(f, tail_sha1, 0);
1112                hashcpy(read_sha1, pack_sha1);
1113                fixup_pack_header_footer(output_fd, pack_sha1,
1114                                         curr_pack, nr_objects,
1115                                         read_sha1, consumed_bytes-20);
1116                if (hashcmp(read_sha1, tail_sha1) != 0)
1117                        die("Unexpected tail checksum for %s "
1118                            "(disk corruption?)", curr_pack);
1119        }
1120        if (nr_deltas != nr_resolved_deltas)
1121                die(Q_("pack has %d unresolved delta",
1122                       "pack has %d unresolved deltas",
1123                       nr_deltas - nr_resolved_deltas),
1124                    nr_deltas - nr_resolved_deltas);
1125}
1126
1127static int write_compressed(struct sha1file *f, void *in, unsigned int size)
1128{
1129        git_zstream stream;
1130        int status;
1131        unsigned char outbuf[4096];
1132
1133        memset(&stream, 0, sizeof(stream));
1134        git_deflate_init(&stream, zlib_compression_level);
1135        stream.next_in = in;
1136        stream.avail_in = size;
1137
1138        do {
1139                stream.next_out = outbuf;
1140                stream.avail_out = sizeof(outbuf);
1141                status = git_deflate(&stream, Z_FINISH);
1142                sha1write(f, outbuf, sizeof(outbuf) - stream.avail_out);
1143        } while (status == Z_OK);
1144
1145        if (status != Z_STREAM_END)
1146                die(_("unable to deflate appended object (%d)"), status);
1147        size = stream.total_out;
1148        git_deflate_end(&stream);
1149        return size;
1150}
1151
1152static struct object_entry *append_obj_to_pack(struct sha1file *f,
1153                               const unsigned char *sha1, void *buf,
1154                               unsigned long size, enum object_type type)
1155{
1156        struct object_entry *obj = &objects[nr_objects++];
1157        unsigned char header[10];
1158        unsigned long s = size;
1159        int n = 0;
1160        unsigned char c = (type << 4) | (s & 15);
1161        s >>= 4;
1162        while (s) {
1163                header[n++] = c | 0x80;
1164                c = s & 0x7f;
1165                s >>= 7;
1166        }
1167        header[n++] = c;
1168        crc32_begin(f);
1169        sha1write(f, header, n);
1170        obj[0].size = size;
1171        obj[0].hdr_size = n;
1172        obj[0].type = type;
1173        obj[0].real_type = type;
1174        obj[1].idx.offset = obj[0].idx.offset + n;
1175        obj[1].idx.offset += write_compressed(f, buf, size);
1176        obj[0].idx.crc32 = crc32_end(f);
1177        sha1flush(f);
1178        hashcpy(obj->idx.sha1, sha1);
1179        return obj;
1180}
1181
1182static int delta_pos_compare(const void *_a, const void *_b)
1183{
1184        struct delta_entry *a = *(struct delta_entry **)_a;
1185        struct delta_entry *b = *(struct delta_entry **)_b;
1186        return a->obj_no - b->obj_no;
1187}
1188
1189static void fix_unresolved_deltas(struct sha1file *f, int nr_unresolved)
1190{
1191        struct delta_entry **sorted_by_pos;
1192        int i, n = 0;
1193
1194        /*
1195         * Since many unresolved deltas may well be themselves base objects
1196         * for more unresolved deltas, we really want to include the
1197         * smallest number of base objects that would cover as much delta
1198         * as possible by picking the
1199         * trunc deltas first, allowing for other deltas to resolve without
1200         * additional base objects.  Since most base objects are to be found
1201         * before deltas depending on them, a good heuristic is to start
1202         * resolving deltas in the same order as their position in the pack.
1203         */
1204        sorted_by_pos = xmalloc(nr_unresolved * sizeof(*sorted_by_pos));
1205        for (i = 0; i < nr_deltas; i++) {
1206                if (objects[deltas[i].obj_no].real_type != OBJ_REF_DELTA)
1207                        continue;
1208                sorted_by_pos[n++] = &deltas[i];
1209        }
1210        qsort(sorted_by_pos, n, sizeof(*sorted_by_pos), delta_pos_compare);
1211
1212        for (i = 0; i < n; i++) {
1213                struct delta_entry *d = sorted_by_pos[i];
1214                enum object_type type;
1215                struct base_data *base_obj = alloc_base_data();
1216
1217                if (objects[d->obj_no].real_type != OBJ_REF_DELTA)
1218                        continue;
1219                base_obj->data = read_sha1_file(d->base.sha1, &type, &base_obj->size);
1220                if (!base_obj->data)
1221                        continue;
1222
1223                if (check_sha1_signature(d->base.sha1, base_obj->data,
1224                                base_obj->size, typename(type)))
1225                        die(_("local object %s is corrupt"), sha1_to_hex(d->base.sha1));
1226                base_obj->obj = append_obj_to_pack(f, d->base.sha1,
1227                                        base_obj->data, base_obj->size, type);
1228                find_unresolved_deltas(base_obj);
1229                display_progress(progress, nr_resolved_deltas);
1230        }
1231        free(sorted_by_pos);
1232}
1233
1234static void final(const char *final_pack_name, const char *curr_pack_name,
1235                  const char *final_index_name, const char *curr_index_name,
1236                  const char *keep_name, const char *keep_msg,
1237                  unsigned char *sha1)
1238{
1239        const char *report = "pack";
1240        char name[PATH_MAX];
1241        int err;
1242
1243        if (!from_stdin) {
1244                close(input_fd);
1245        } else {
1246                fsync_or_die(output_fd, curr_pack_name);
1247                err = close(output_fd);
1248                if (err)
1249                        die_errno(_("error while closing pack file"));
1250        }
1251
1252        if (keep_msg) {
1253                int keep_fd, keep_msg_len = strlen(keep_msg);
1254
1255                if (!keep_name)
1256                        keep_fd = odb_pack_keep(name, sizeof(name), sha1);
1257                else
1258                        keep_fd = open(keep_name, O_RDWR|O_CREAT|O_EXCL, 0600);
1259
1260                if (keep_fd < 0) {
1261                        if (errno != EEXIST)
1262                                die_errno(_("cannot write keep file '%s'"),
1263                                          keep_name);
1264                } else {
1265                        if (keep_msg_len > 0) {
1266                                write_or_die(keep_fd, keep_msg, keep_msg_len);
1267                                write_or_die(keep_fd, "\n", 1);
1268                        }
1269                        if (close(keep_fd) != 0)
1270                                die_errno(_("cannot close written keep file '%s'"),
1271                                    keep_name);
1272                        report = "keep";
1273                }
1274        }
1275
1276        if (final_pack_name != curr_pack_name) {
1277                if (!final_pack_name) {
1278                        snprintf(name, sizeof(name), "%s/pack/pack-%s.pack",
1279                                 get_object_directory(), sha1_to_hex(sha1));
1280                        final_pack_name = name;
1281                }
1282                if (move_temp_to_file(curr_pack_name, final_pack_name))
1283                        die(_("cannot store pack file"));
1284        } else if (from_stdin)
1285                chmod(final_pack_name, 0444);
1286
1287        if (final_index_name != curr_index_name) {
1288                if (!final_index_name) {
1289                        snprintf(name, sizeof(name), "%s/pack/pack-%s.idx",
1290                                 get_object_directory(), sha1_to_hex(sha1));
1291                        final_index_name = name;
1292                }
1293                if (move_temp_to_file(curr_index_name, final_index_name))
1294                        die(_("cannot store index file"));
1295        } else
1296                chmod(final_index_name, 0444);
1297
1298        if (!from_stdin) {
1299                printf("%s\n", sha1_to_hex(sha1));
1300        } else {
1301                char buf[48];
1302                int len = snprintf(buf, sizeof(buf), "%s\t%s\n",
1303                                   report, sha1_to_hex(sha1));
1304                write_or_die(1, buf, len);
1305
1306                /*
1307                 * Let's just mimic git-unpack-objects here and write
1308                 * the last part of the input buffer to stdout.
1309                 */
1310                while (input_len) {
1311                        err = xwrite(1, input_buffer + input_offset, input_len);
1312                        if (err <= 0)
1313                                break;
1314                        input_len -= err;
1315                        input_offset += err;
1316                }
1317        }
1318}
1319
1320static int git_index_pack_config(const char *k, const char *v, void *cb)
1321{
1322        struct pack_idx_option *opts = cb;
1323
1324        if (!strcmp(k, "pack.indexversion")) {
1325                opts->version = git_config_int(k, v);
1326                if (opts->version > 2)
1327                        die("bad pack.indexversion=%"PRIu32, opts->version);
1328                return 0;
1329        }
1330        if (!strcmp(k, "pack.threads")) {
1331                nr_threads = git_config_int(k, v);
1332                if (nr_threads < 0)
1333                        die("invalid number of threads specified (%d)",
1334                            nr_threads);
1335#ifdef NO_PTHREADS
1336                if (nr_threads != 1)
1337                        warning("no threads support, ignoring %s", k);
1338                nr_threads = 1;
1339#endif
1340                return 0;
1341        }
1342        return git_default_config(k, v, cb);
1343}
1344
1345static int cmp_uint32(const void *a_, const void *b_)
1346{
1347        uint32_t a = *((uint32_t *)a_);
1348        uint32_t b = *((uint32_t *)b_);
1349
1350        return (a < b) ? -1 : (a != b);
1351}
1352
1353static void read_v2_anomalous_offsets(struct packed_git *p,
1354                                      struct pack_idx_option *opts)
1355{
1356        const uint32_t *idx1, *idx2;
1357        uint32_t i;
1358
1359        /* The address of the 4-byte offset table */
1360        idx1 = (((const uint32_t *)p->index_data)
1361                + 2 /* 8-byte header */
1362                + 256 /* fan out */
1363                + 5 * p->num_objects /* 20-byte SHA-1 table */
1364                + p->num_objects /* CRC32 table */
1365                );
1366
1367        /* The address of the 8-byte offset table */
1368        idx2 = idx1 + p->num_objects;
1369
1370        for (i = 0; i < p->num_objects; i++) {
1371                uint32_t off = ntohl(idx1[i]);
1372                if (!(off & 0x80000000))
1373                        continue;
1374                off = off & 0x7fffffff;
1375                if (idx2[off * 2])
1376                        continue;
1377                /*
1378                 * The real offset is ntohl(idx2[off * 2]) in high 4
1379                 * octets, and ntohl(idx2[off * 2 + 1]) in low 4
1380                 * octets.  But idx2[off * 2] is Zero!!!
1381                 */
1382                ALLOC_GROW(opts->anomaly, opts->anomaly_nr + 1, opts->anomaly_alloc);
1383                opts->anomaly[opts->anomaly_nr++] = ntohl(idx2[off * 2 + 1]);
1384        }
1385
1386        if (1 < opts->anomaly_nr)
1387                qsort(opts->anomaly, opts->anomaly_nr, sizeof(uint32_t), cmp_uint32);
1388}
1389
1390static void read_idx_option(struct pack_idx_option *opts, const char *pack_name)
1391{
1392        struct packed_git *p = add_packed_git(pack_name, strlen(pack_name), 1);
1393
1394        if (!p)
1395                die(_("Cannot open existing pack file '%s'"), pack_name);
1396        if (open_pack_index(p))
1397                die(_("Cannot open existing pack idx file for '%s'"), pack_name);
1398
1399        /* Read the attributes from the existing idx file */
1400        opts->version = p->index_version;
1401
1402        if (opts->version == 2)
1403                read_v2_anomalous_offsets(p, opts);
1404
1405        /*
1406         * Get rid of the idx file as we do not need it anymore.
1407         * NEEDSWORK: extract this bit from free_pack_by_name() in
1408         * sha1_file.c, perhaps?  It shouldn't matter very much as we
1409         * know we haven't installed this pack (hence we never have
1410         * read anything from it).
1411         */
1412        close_pack_index(p);
1413        free(p);
1414}
1415
1416static void show_pack_info(int stat_only)
1417{
1418        int i, baseobjects = nr_objects - nr_deltas;
1419        unsigned long *chain_histogram = NULL;
1420
1421        if (deepest_delta)
1422                chain_histogram = xcalloc(deepest_delta, sizeof(unsigned long));
1423
1424        for (i = 0; i < nr_objects; i++) {
1425                struct object_entry *obj = &objects[i];
1426
1427                if (is_delta_type(obj->type))
1428                        chain_histogram[obj->delta_depth - 1]++;
1429                if (stat_only)
1430                        continue;
1431                printf("%s %-6s %lu %lu %"PRIuMAX,
1432                       sha1_to_hex(obj->idx.sha1),
1433                       typename(obj->real_type), obj->size,
1434                       (unsigned long)(obj[1].idx.offset - obj->idx.offset),
1435                       (uintmax_t)obj->idx.offset);
1436                if (is_delta_type(obj->type)) {
1437                        struct object_entry *bobj = &objects[obj->base_object_no];
1438                        printf(" %u %s", obj->delta_depth, sha1_to_hex(bobj->idx.sha1));
1439                }
1440                putchar('\n');
1441        }
1442
1443        if (baseobjects)
1444                printf_ln(Q_("non delta: %d object",
1445                             "non delta: %d objects",
1446                             baseobjects),
1447                          baseobjects);
1448        for (i = 0; i < deepest_delta; i++) {
1449                if (!chain_histogram[i])
1450                        continue;
1451                printf_ln(Q_("chain length = %d: %lu object",
1452                             "chain length = %d: %lu objects",
1453                             chain_histogram[i]),
1454                          i + 1,
1455                          chain_histogram[i]);
1456        }
1457}
1458
1459int cmd_index_pack(int argc, const char **argv, const char *prefix)
1460{
1461        int i, fix_thin_pack = 0, verify = 0, stat_only = 0, stat = 0;
1462        const char *curr_pack, *curr_index;
1463        const char *index_name = NULL, *pack_name = NULL;
1464        const char *keep_name = NULL, *keep_msg = NULL;
1465        char *index_name_buf = NULL, *keep_name_buf = NULL;
1466        struct pack_idx_entry **idx_objects;
1467        struct pack_idx_option opts;
1468        unsigned char pack_sha1[20];
1469
1470        if (argc == 2 && !strcmp(argv[1], "-h"))
1471                usage(index_pack_usage);
1472
1473        read_replace_refs = 0;
1474
1475        reset_pack_idx_option(&opts);
1476        git_config(git_index_pack_config, &opts);
1477        if (prefix && chdir(prefix))
1478                die(_("Cannot come back to cwd"));
1479
1480        for (i = 1; i < argc; i++) {
1481                const char *arg = argv[i];
1482
1483                if (*arg == '-') {
1484                        if (!strcmp(arg, "--stdin")) {
1485                                from_stdin = 1;
1486                        } else if (!strcmp(arg, "--fix-thin")) {
1487                                fix_thin_pack = 1;
1488                        } else if (!strcmp(arg, "--strict")) {
1489                                strict = 1;
1490                        } else if (!strcmp(arg, "--verify")) {
1491                                verify = 1;
1492                        } else if (!strcmp(arg, "--verify-stat")) {
1493                                verify = 1;
1494                                stat = 1;
1495                        } else if (!strcmp(arg, "--verify-stat-only")) {
1496                                verify = 1;
1497                                stat = 1;
1498                                stat_only = 1;
1499                        } else if (!strcmp(arg, "--keep")) {
1500                                keep_msg = "";
1501                        } else if (!prefixcmp(arg, "--keep=")) {
1502                                keep_msg = arg + 7;
1503                        } else if (!prefixcmp(arg, "--threads=")) {
1504                                char *end;
1505                                nr_threads = strtoul(arg+10, &end, 0);
1506                                if (!arg[10] || *end || nr_threads < 0)
1507                                        usage(index_pack_usage);
1508#ifdef NO_PTHREADS
1509                                if (nr_threads != 1)
1510                                        warning("no threads support, "
1511                                                "ignoring %s", arg);
1512                                nr_threads = 1;
1513#endif
1514                        } else if (!prefixcmp(arg, "--pack_header=")) {
1515                                struct pack_header *hdr;
1516                                char *c;
1517
1518                                hdr = (struct pack_header *)input_buffer;
1519                                hdr->hdr_signature = htonl(PACK_SIGNATURE);
1520                                hdr->hdr_version = htonl(strtoul(arg + 14, &c, 10));
1521                                if (*c != ',')
1522                                        die(_("bad %s"), arg);
1523                                hdr->hdr_entries = htonl(strtoul(c + 1, &c, 10));
1524                                if (*c)
1525                                        die(_("bad %s"), arg);
1526                                input_len = sizeof(*hdr);
1527                        } else if (!strcmp(arg, "-v")) {
1528                                verbose = 1;
1529                        } else if (!strcmp(arg, "-o")) {
1530                                if (index_name || (i+1) >= argc)
1531                                        usage(index_pack_usage);
1532                                index_name = argv[++i];
1533                        } else if (!prefixcmp(arg, "--index-version=")) {
1534                                char *c;
1535                                opts.version = strtoul(arg + 16, &c, 10);
1536                                if (opts.version > 2)
1537                                        die(_("bad %s"), arg);
1538                                if (*c == ',')
1539                                        opts.off32_limit = strtoul(c+1, &c, 0);
1540                                if (*c || opts.off32_limit & 0x80000000)
1541                                        die(_("bad %s"), arg);
1542                        } else
1543                                usage(index_pack_usage);
1544                        continue;
1545                }
1546
1547                if (pack_name)
1548                        usage(index_pack_usage);
1549                pack_name = arg;
1550        }
1551
1552        if (!pack_name && !from_stdin)
1553                usage(index_pack_usage);
1554        if (fix_thin_pack && !from_stdin)
1555                die(_("--fix-thin cannot be used without --stdin"));
1556        if (!index_name && pack_name) {
1557                int len = strlen(pack_name);
1558                if (!has_extension(pack_name, ".pack"))
1559                        die(_("packfile name '%s' does not end with '.pack'"),
1560                            pack_name);
1561                index_name_buf = xmalloc(len);
1562                memcpy(index_name_buf, pack_name, len - 5);
1563                strcpy(index_name_buf + len - 5, ".idx");
1564                index_name = index_name_buf;
1565        }
1566        if (keep_msg && !keep_name && pack_name) {
1567                int len = strlen(pack_name);
1568                if (!has_extension(pack_name, ".pack"))
1569                        die(_("packfile name '%s' does not end with '.pack'"),
1570                            pack_name);
1571                keep_name_buf = xmalloc(len);
1572                memcpy(keep_name_buf, pack_name, len - 5);
1573                strcpy(keep_name_buf + len - 5, ".keep");
1574                keep_name = keep_name_buf;
1575        }
1576        if (verify) {
1577                if (!index_name)
1578                        die(_("--verify with no packfile name given"));
1579                read_idx_option(&opts, index_name);
1580                opts.flags |= WRITE_IDX_VERIFY | WRITE_IDX_STRICT;
1581        }
1582        if (strict)
1583                opts.flags |= WRITE_IDX_STRICT;
1584
1585#ifndef NO_PTHREADS
1586        if (!nr_threads) {
1587                nr_threads = online_cpus();
1588                /* An experiment showed that more threads does not mean faster */
1589                if (nr_threads > 3)
1590                        nr_threads = 3;
1591        }
1592#endif
1593
1594        curr_pack = open_pack_file(pack_name);
1595        parse_pack_header();
1596        objects = xcalloc(nr_objects + 1, sizeof(struct object_entry));
1597        deltas = xcalloc(nr_objects, sizeof(struct delta_entry));
1598        parse_pack_objects(pack_sha1);
1599        resolve_deltas();
1600        conclude_pack(fix_thin_pack, curr_pack, pack_sha1);
1601        free(deltas);
1602        if (strict)
1603                check_objects();
1604
1605        if (stat)
1606                show_pack_info(stat_only);
1607
1608        idx_objects = xmalloc((nr_objects) * sizeof(struct pack_idx_entry *));
1609        for (i = 0; i < nr_objects; i++)
1610                idx_objects[i] = &objects[i].idx;
1611        curr_index = write_idx_file(index_name, idx_objects, nr_objects, &opts, pack_sha1);
1612        free(idx_objects);
1613
1614        if (!verify)
1615                final(pack_name, curr_pack,
1616                      index_name, curr_index,
1617                      keep_name, keep_msg,
1618                      pack_sha1);
1619        else
1620                close(input_fd);
1621        free(objects);
1622        free(index_name_buf);
1623        free(keep_name_buf);
1624        if (pack_name == NULL)
1625                free((void *) curr_pack);
1626        if (index_name == NULL)
1627                free((void *) curr_index);
1628
1629        return 0;
1630}