builtin-pack-objects.con commit Merge branch 'eb/upload-archive-from-git-shell' (ef5542c)
   1#include "builtin.h"
   2#include "cache.h"
   3#include "attr.h"
   4#include "object.h"
   5#include "blob.h"
   6#include "commit.h"
   7#include "tag.h"
   8#include "tree.h"
   9#include "delta.h"
  10#include "pack.h"
  11#include "pack-revindex.h"
  12#include "csum-file.h"
  13#include "tree-walk.h"
  14#include "diff.h"
  15#include "revision.h"
  16#include "list-objects.h"
  17#include "progress.h"
  18#include "refs.h"
  19
  20#ifdef THREADED_DELTA_SEARCH
  21#include "thread-utils.h"
  22#include <pthread.h>
  23#endif
  24
  25static const char pack_usage[] = "\
  26git pack-objects [{ -q | --progress | --all-progress }] \n\
  27        [--max-pack-size=N] [--local] [--incremental] \n\
  28        [--window=N] [--window-memory=N] [--depth=N] \n\
  29        [--no-reuse-delta] [--no-reuse-object] [--delta-base-offset] \n\
  30        [--threads=N] [--non-empty] [--revs [--unpacked | --all]*] [--reflog] \n\
  31        [--stdout | base-name] [--include-tag] \n\
  32        [--keep-unreachable | --unpack-unreachable] \n\
  33        [<ref-list | <object-list]";
  34
  35struct object_entry {
  36        struct pack_idx_entry idx;
  37        unsigned long size;     /* uncompressed size */
  38        struct packed_git *in_pack;     /* already in pack */
  39        off_t in_pack_offset;
  40        struct object_entry *delta;     /* delta base object */
  41        struct object_entry *delta_child; /* deltified objects who bases me */
  42        struct object_entry *delta_sibling; /* other deltified objects who
  43                                             * uses the same base as me
  44                                             */
  45        void *delta_data;       /* cached delta (uncompressed) */
  46        unsigned long delta_size;       /* delta data size (uncompressed) */
  47        unsigned long z_delta_size;     /* delta data size (compressed) */
  48        unsigned int hash;      /* name hint hash */
  49        enum object_type type;
  50        enum object_type in_pack_type;  /* could be delta */
  51        unsigned char in_pack_header_size;
  52        unsigned char preferred_base; /* we do not pack this, but is available
  53                                       * to be used as the base object to delta
  54                                       * objects against.
  55                                       */
  56        unsigned char no_try_delta;
  57};
  58
  59/*
  60 * Objects we are going to pack are collected in objects array (dynamically
  61 * expanded).  nr_objects & nr_alloc controls this array.  They are stored
  62 * in the order we see -- typically rev-list --objects order that gives us
  63 * nice "minimum seek" order.
  64 */
  65static struct object_entry *objects;
  66static struct pack_idx_entry **written_list;
  67static uint32_t nr_objects, nr_alloc, nr_result, nr_written;
  68
  69static int non_empty;
  70static int reuse_delta = 1, reuse_object = 1;
  71static int keep_unreachable, unpack_unreachable, include_tag;
  72static int local;
  73static int incremental;
  74static int ignore_packed_keep;
  75static int allow_ofs_delta;
  76static const char *base_name;
  77static int progress = 1;
  78static int window = 10;
  79static uint32_t pack_size_limit, pack_size_limit_cfg;
  80static int depth = 50;
  81static int delta_search_threads;
  82static int pack_to_stdout;
  83static int num_preferred_base;
  84static struct progress *progress_state;
  85static int pack_compression_level = Z_DEFAULT_COMPRESSION;
  86static int pack_compression_seen;
  87
  88static unsigned long delta_cache_size = 0;
  89static unsigned long max_delta_cache_size = 0;
  90static unsigned long cache_max_small_delta_size = 1000;
  91
  92static unsigned long window_memory_limit = 0;
  93
  94/*
  95 * The object names in objects array are hashed with this hashtable,
  96 * to help looking up the entry by object name.
  97 * This hashtable is built after all the objects are seen.
  98 */
  99static int *object_ix;
 100static int object_ix_hashsz;
 101
 102/*
 103 * stats
 104 */
 105static uint32_t written, written_delta;
 106static uint32_t reused, reused_delta;
 107
 108
 109static void *get_delta(struct object_entry *entry)
 110{
 111        unsigned long size, base_size, delta_size;
 112        void *buf, *base_buf, *delta_buf;
 113        enum object_type type;
 114
 115        buf = read_sha1_file(entry->idx.sha1, &type, &size);
 116        if (!buf)
 117                die("unable to read %s", sha1_to_hex(entry->idx.sha1));
 118        base_buf = read_sha1_file(entry->delta->idx.sha1, &type, &base_size);
 119        if (!base_buf)
 120                die("unable to read %s", sha1_to_hex(entry->delta->idx.sha1));
 121        delta_buf = diff_delta(base_buf, base_size,
 122                               buf, size, &delta_size, 0);
 123        if (!delta_buf || delta_size != entry->delta_size)
 124                die("delta size changed");
 125        free(buf);
 126        free(base_buf);
 127        return delta_buf;
 128}
 129
 130static unsigned long do_compress(void **pptr, unsigned long size)
 131{
 132        z_stream stream;
 133        void *in, *out;
 134        unsigned long maxsize;
 135
 136        memset(&stream, 0, sizeof(stream));
 137        deflateInit(&stream, pack_compression_level);
 138        maxsize = deflateBound(&stream, size);
 139
 140        in = *pptr;
 141        out = xmalloc(maxsize);
 142        *pptr = out;
 143
 144        stream.next_in = in;
 145        stream.avail_in = size;
 146        stream.next_out = out;
 147        stream.avail_out = maxsize;
 148        while (deflate(&stream, Z_FINISH) == Z_OK)
 149                ; /* nothing */
 150        deflateEnd(&stream);
 151
 152        free(in);
 153        return stream.total_out;
 154}
 155
 156/*
 157 * The per-object header is a pretty dense thing, which is
 158 *  - first byte: low four bits are "size", then three bits of "type",
 159 *    and the high bit is "size continues".
 160 *  - each byte afterwards: low seven bits are size continuation,
 161 *    with the high bit being "size continues"
 162 */
 163static int encode_header(enum object_type type, unsigned long size, unsigned char *hdr)
 164{
 165        int n = 1;
 166        unsigned char c;
 167
 168        if (type < OBJ_COMMIT || type > OBJ_REF_DELTA)
 169                die("bad type %d", type);
 170
 171        c = (type << 4) | (size & 15);
 172        size >>= 4;
 173        while (size) {
 174                *hdr++ = c | 0x80;
 175                c = size & 0x7f;
 176                size >>= 7;
 177                n++;
 178        }
 179        *hdr = c;
 180        return n;
 181}
 182
 183/*
 184 * we are going to reuse the existing object data as is.  make
 185 * sure it is not corrupt.
 186 */
 187static int check_pack_inflate(struct packed_git *p,
 188                struct pack_window **w_curs,
 189                off_t offset,
 190                off_t len,
 191                unsigned long expect)
 192{
 193        z_stream stream;
 194        unsigned char fakebuf[4096], *in;
 195        int st;
 196
 197        memset(&stream, 0, sizeof(stream));
 198        git_inflate_init(&stream);
 199        do {
 200                in = use_pack(p, w_curs, offset, &stream.avail_in);
 201                stream.next_in = in;
 202                stream.next_out = fakebuf;
 203                stream.avail_out = sizeof(fakebuf);
 204                st = git_inflate(&stream, Z_FINISH);
 205                offset += stream.next_in - in;
 206        } while (st == Z_OK || st == Z_BUF_ERROR);
 207        git_inflate_end(&stream);
 208        return (st == Z_STREAM_END &&
 209                stream.total_out == expect &&
 210                stream.total_in == len) ? 0 : -1;
 211}
 212
 213static void copy_pack_data(struct sha1file *f,
 214                struct packed_git *p,
 215                struct pack_window **w_curs,
 216                off_t offset,
 217                off_t len)
 218{
 219        unsigned char *in;
 220        unsigned int avail;
 221
 222        while (len) {
 223                in = use_pack(p, w_curs, offset, &avail);
 224                if (avail > len)
 225                        avail = (unsigned int)len;
 226                sha1write(f, in, avail);
 227                offset += avail;
 228                len -= avail;
 229        }
 230}
 231
 232static unsigned long write_object(struct sha1file *f,
 233                                  struct object_entry *entry,
 234                                  off_t write_offset)
 235{
 236        unsigned long size, limit, datalen;
 237        void *buf;
 238        unsigned char header[10], dheader[10];
 239        unsigned hdrlen;
 240        enum object_type type;
 241        int usable_delta, to_reuse;
 242
 243        if (!pack_to_stdout)
 244                crc32_begin(f);
 245
 246        type = entry->type;
 247
 248        /* write limit if limited packsize and not first object */
 249        if (!pack_size_limit || !nr_written)
 250                limit = 0;
 251        else if (pack_size_limit <= write_offset)
 252                /*
 253                 * the earlier object did not fit the limit; avoid
 254                 * mistaking this with unlimited (i.e. limit = 0).
 255                 */
 256                limit = 1;
 257        else
 258                limit = pack_size_limit - write_offset;
 259
 260        if (!entry->delta)
 261                usable_delta = 0;       /* no delta */
 262        else if (!pack_size_limit)
 263               usable_delta = 1;        /* unlimited packfile */
 264        else if (entry->delta->idx.offset == (off_t)-1)
 265                usable_delta = 0;       /* base was written to another pack */
 266        else if (entry->delta->idx.offset)
 267                usable_delta = 1;       /* base already exists in this pack */
 268        else
 269                usable_delta = 0;       /* base could end up in another pack */
 270
 271        if (!reuse_object)
 272                to_reuse = 0;   /* explicit */
 273        else if (!entry->in_pack)
 274                to_reuse = 0;   /* can't reuse what we don't have */
 275        else if (type == OBJ_REF_DELTA || type == OBJ_OFS_DELTA)
 276                                /* check_object() decided it for us ... */
 277                to_reuse = usable_delta;
 278                                /* ... but pack split may override that */
 279        else if (type != entry->in_pack_type)
 280                to_reuse = 0;   /* pack has delta which is unusable */
 281        else if (entry->delta)
 282                to_reuse = 0;   /* we want to pack afresh */
 283        else
 284                to_reuse = 1;   /* we have it in-pack undeltified,
 285                                 * and we do not need to deltify it.
 286                                 */
 287
 288        if (!to_reuse) {
 289                no_reuse:
 290                if (!usable_delta) {
 291                        buf = read_sha1_file(entry->idx.sha1, &type, &size);
 292                        if (!buf)
 293                                die("unable to read %s", sha1_to_hex(entry->idx.sha1));
 294                        /*
 295                         * make sure no cached delta data remains from a
 296                         * previous attempt before a pack split occured.
 297                         */
 298                        free(entry->delta_data);
 299                        entry->delta_data = NULL;
 300                        entry->z_delta_size = 0;
 301                } else if (entry->delta_data) {
 302                        size = entry->delta_size;
 303                        buf = entry->delta_data;
 304                        entry->delta_data = NULL;
 305                        type = (allow_ofs_delta && entry->delta->idx.offset) ?
 306                                OBJ_OFS_DELTA : OBJ_REF_DELTA;
 307                } else {
 308                        buf = get_delta(entry);
 309                        size = entry->delta_size;
 310                        type = (allow_ofs_delta && entry->delta->idx.offset) ?
 311                                OBJ_OFS_DELTA : OBJ_REF_DELTA;
 312                }
 313
 314                if (entry->z_delta_size)
 315                        datalen = entry->z_delta_size;
 316                else
 317                        datalen = do_compress(&buf, size);
 318
 319                /*
 320                 * The object header is a byte of 'type' followed by zero or
 321                 * more bytes of length.
 322                 */
 323                hdrlen = encode_header(type, size, header);
 324
 325                if (type == OBJ_OFS_DELTA) {
 326                        /*
 327                         * Deltas with relative base contain an additional
 328                         * encoding of the relative offset for the delta
 329                         * base from this object's position in the pack.
 330                         */
 331                        off_t ofs = entry->idx.offset - entry->delta->idx.offset;
 332                        unsigned pos = sizeof(dheader) - 1;
 333                        dheader[pos] = ofs & 127;
 334                        while (ofs >>= 7)
 335                                dheader[--pos] = 128 | (--ofs & 127);
 336                        if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit) {
 337                                free(buf);
 338                                return 0;
 339                        }
 340                        sha1write(f, header, hdrlen);
 341                        sha1write(f, dheader + pos, sizeof(dheader) - pos);
 342                        hdrlen += sizeof(dheader) - pos;
 343                } else if (type == OBJ_REF_DELTA) {
 344                        /*
 345                         * Deltas with a base reference contain
 346                         * an additional 20 bytes for the base sha1.
 347                         */
 348                        if (limit && hdrlen + 20 + datalen + 20 >= limit) {
 349                                free(buf);
 350                                return 0;
 351                        }
 352                        sha1write(f, header, hdrlen);
 353                        sha1write(f, entry->delta->idx.sha1, 20);
 354                        hdrlen += 20;
 355                } else {
 356                        if (limit && hdrlen + datalen + 20 >= limit) {
 357                                free(buf);
 358                                return 0;
 359                        }
 360                        sha1write(f, header, hdrlen);
 361                }
 362                sha1write(f, buf, datalen);
 363                free(buf);
 364        }
 365        else {
 366                struct packed_git *p = entry->in_pack;
 367                struct pack_window *w_curs = NULL;
 368                struct revindex_entry *revidx;
 369                off_t offset;
 370
 371                if (entry->delta)
 372                        type = (allow_ofs_delta && entry->delta->idx.offset) ?
 373                                OBJ_OFS_DELTA : OBJ_REF_DELTA;
 374                hdrlen = encode_header(type, entry->size, header);
 375
 376                offset = entry->in_pack_offset;
 377                revidx = find_pack_revindex(p, offset);
 378                datalen = revidx[1].offset - offset;
 379                if (!pack_to_stdout && p->index_version > 1 &&
 380                    check_pack_crc(p, &w_curs, offset, datalen, revidx->nr)) {
 381                        error("bad packed object CRC for %s", sha1_to_hex(entry->idx.sha1));
 382                        unuse_pack(&w_curs);
 383                        goto no_reuse;
 384                }
 385
 386                offset += entry->in_pack_header_size;
 387                datalen -= entry->in_pack_header_size;
 388                if (!pack_to_stdout && p->index_version == 1 &&
 389                    check_pack_inflate(p, &w_curs, offset, datalen, entry->size)) {
 390                        error("corrupt packed object for %s", sha1_to_hex(entry->idx.sha1));
 391                        unuse_pack(&w_curs);
 392                        goto no_reuse;
 393                }
 394
 395                if (type == OBJ_OFS_DELTA) {
 396                        off_t ofs = entry->idx.offset - entry->delta->idx.offset;
 397                        unsigned pos = sizeof(dheader) - 1;
 398                        dheader[pos] = ofs & 127;
 399                        while (ofs >>= 7)
 400                                dheader[--pos] = 128 | (--ofs & 127);
 401                        if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit) {
 402                                unuse_pack(&w_curs);
 403                                return 0;
 404                        }
 405                        sha1write(f, header, hdrlen);
 406                        sha1write(f, dheader + pos, sizeof(dheader) - pos);
 407                        hdrlen += sizeof(dheader) - pos;
 408                        reused_delta++;
 409                } else if (type == OBJ_REF_DELTA) {
 410                        if (limit && hdrlen + 20 + datalen + 20 >= limit) {
 411                                unuse_pack(&w_curs);
 412                                return 0;
 413                        }
 414                        sha1write(f, header, hdrlen);
 415                        sha1write(f, entry->delta->idx.sha1, 20);
 416                        hdrlen += 20;
 417                        reused_delta++;
 418                } else {
 419                        if (limit && hdrlen + datalen + 20 >= limit) {
 420                                unuse_pack(&w_curs);
 421                                return 0;
 422                        }
 423                        sha1write(f, header, hdrlen);
 424                }
 425                copy_pack_data(f, p, &w_curs, offset, datalen);
 426                unuse_pack(&w_curs);
 427                reused++;
 428        }
 429        if (usable_delta)
 430                written_delta++;
 431        written++;
 432        if (!pack_to_stdout)
 433                entry->idx.crc32 = crc32_end(f);
 434        return hdrlen + datalen;
 435}
 436
 437static int write_one(struct sha1file *f,
 438                               struct object_entry *e,
 439                               off_t *offset)
 440{
 441        unsigned long size;
 442
 443        /* offset is non zero if object is written already. */
 444        if (e->idx.offset || e->preferred_base)
 445                return 1;
 446
 447        /* if we are deltified, write out base object first. */
 448        if (e->delta && !write_one(f, e->delta, offset))
 449                return 0;
 450
 451        e->idx.offset = *offset;
 452        size = write_object(f, e, *offset);
 453        if (!size) {
 454                e->idx.offset = 0;
 455                return 0;
 456        }
 457        written_list[nr_written++] = &e->idx;
 458
 459        /* make sure off_t is sufficiently large not to wrap */
 460        if (*offset > *offset + size)
 461                die("pack too large for current definition of off_t");
 462        *offset += size;
 463        return 1;
 464}
 465
 466/* forward declaration for write_pack_file */
 467static int adjust_perm(const char *path, mode_t mode);
 468
 469static void write_pack_file(void)
 470{
 471        uint32_t i = 0, j;
 472        struct sha1file *f;
 473        off_t offset;
 474        struct pack_header hdr;
 475        uint32_t nr_remaining = nr_result;
 476        time_t last_mtime = 0;
 477
 478        if (progress > pack_to_stdout)
 479                progress_state = start_progress("Writing objects", nr_result);
 480        written_list = xmalloc(nr_objects * sizeof(*written_list));
 481
 482        do {
 483                unsigned char sha1[20];
 484                char *pack_tmp_name = NULL;
 485
 486                if (pack_to_stdout) {
 487                        f = sha1fd_throughput(1, "<stdout>", progress_state);
 488                } else {
 489                        char tmpname[PATH_MAX];
 490                        int fd;
 491                        fd = odb_mkstemp(tmpname, sizeof(tmpname),
 492                                         "pack/tmp_pack_XXXXXX");
 493                        pack_tmp_name = xstrdup(tmpname);
 494                        f = sha1fd(fd, pack_tmp_name);
 495                }
 496
 497                hdr.hdr_signature = htonl(PACK_SIGNATURE);
 498                hdr.hdr_version = htonl(PACK_VERSION);
 499                hdr.hdr_entries = htonl(nr_remaining);
 500                sha1write(f, &hdr, sizeof(hdr));
 501                offset = sizeof(hdr);
 502                nr_written = 0;
 503                for (; i < nr_objects; i++) {
 504                        if (!write_one(f, objects + i, &offset))
 505                                break;
 506                        display_progress(progress_state, written);
 507                }
 508
 509                /*
 510                 * Did we write the wrong # entries in the header?
 511                 * If so, rewrite it like in fast-import
 512                 */
 513                if (pack_to_stdout) {
 514                        sha1close(f, sha1, CSUM_CLOSE);
 515                } else if (nr_written == nr_remaining) {
 516                        sha1close(f, sha1, CSUM_FSYNC);
 517                } else {
 518                        int fd = sha1close(f, sha1, 0);
 519                        fixup_pack_header_footer(fd, sha1, pack_tmp_name,
 520                                                 nr_written, sha1, offset);
 521                        close(fd);
 522                }
 523
 524                if (!pack_to_stdout) {
 525                        mode_t mode = umask(0);
 526                        struct stat st;
 527                        char *idx_tmp_name, tmpname[PATH_MAX];
 528
 529                        umask(mode);
 530                        mode = 0444 & ~mode;
 531
 532                        idx_tmp_name = write_idx_file(NULL, written_list,
 533                                                      nr_written, sha1);
 534
 535                        snprintf(tmpname, sizeof(tmpname), "%s-%s.pack",
 536                                 base_name, sha1_to_hex(sha1));
 537                        free_pack_by_name(tmpname);
 538                        if (adjust_perm(pack_tmp_name, mode))
 539                                die("unable to make temporary pack file readable: %s",
 540                                    strerror(errno));
 541                        if (rename(pack_tmp_name, tmpname))
 542                                die("unable to rename temporary pack file: %s",
 543                                    strerror(errno));
 544
 545                        /*
 546                         * Packs are runtime accessed in their mtime
 547                         * order since newer packs are more likely to contain
 548                         * younger objects.  So if we are creating multiple
 549                         * packs then we should modify the mtime of later ones
 550                         * to preserve this property.
 551                         */
 552                        if (stat(tmpname, &st) < 0) {
 553                                warning("failed to stat %s: %s",
 554                                        tmpname, strerror(errno));
 555                        } else if (!last_mtime) {
 556                                last_mtime = st.st_mtime;
 557                        } else {
 558                                struct utimbuf utb;
 559                                utb.actime = st.st_atime;
 560                                utb.modtime = --last_mtime;
 561                                if (utime(tmpname, &utb) < 0)
 562                                        warning("failed utime() on %s: %s",
 563                                                tmpname, strerror(errno));
 564                        }
 565
 566                        snprintf(tmpname, sizeof(tmpname), "%s-%s.idx",
 567                                 base_name, sha1_to_hex(sha1));
 568                        if (adjust_perm(idx_tmp_name, mode))
 569                                die("unable to make temporary index file readable: %s",
 570                                    strerror(errno));
 571                        if (rename(idx_tmp_name, tmpname))
 572                                die("unable to rename temporary index file: %s",
 573                                    strerror(errno));
 574
 575                        free(idx_tmp_name);
 576                        free(pack_tmp_name);
 577                        puts(sha1_to_hex(sha1));
 578                }
 579
 580                /* mark written objects as written to previous pack */
 581                for (j = 0; j < nr_written; j++) {
 582                        written_list[j]->offset = (off_t)-1;
 583                }
 584                nr_remaining -= nr_written;
 585        } while (nr_remaining && i < nr_objects);
 586
 587        free(written_list);
 588        stop_progress(&progress_state);
 589        if (written != nr_result)
 590                die("wrote %"PRIu32" objects while expecting %"PRIu32,
 591                        written, nr_result);
 592        /*
 593         * We have scanned through [0 ... i).  Since we have written
 594         * the correct number of objects,  the remaining [i ... nr_objects)
 595         * items must be either already written (due to out-of-order delta base)
 596         * or a preferred base.  Count those which are neither and complain if any.
 597         */
 598        for (j = 0; i < nr_objects; i++) {
 599                struct object_entry *e = objects + i;
 600                j += !e->idx.offset && !e->preferred_base;
 601        }
 602        if (j)
 603                die("wrote %"PRIu32" objects as expected but %"PRIu32
 604                        " unwritten", written, j);
 605}
 606
 607static int locate_object_entry_hash(const unsigned char *sha1)
 608{
 609        int i;
 610        unsigned int ui;
 611        memcpy(&ui, sha1, sizeof(unsigned int));
 612        i = ui % object_ix_hashsz;
 613        while (0 < object_ix[i]) {
 614                if (!hashcmp(sha1, objects[object_ix[i] - 1].idx.sha1))
 615                        return i;
 616                if (++i == object_ix_hashsz)
 617                        i = 0;
 618        }
 619        return -1 - i;
 620}
 621
 622static struct object_entry *locate_object_entry(const unsigned char *sha1)
 623{
 624        int i;
 625
 626        if (!object_ix_hashsz)
 627                return NULL;
 628
 629        i = locate_object_entry_hash(sha1);
 630        if (0 <= i)
 631                return &objects[object_ix[i]-1];
 632        return NULL;
 633}
 634
 635static void rehash_objects(void)
 636{
 637        uint32_t i;
 638        struct object_entry *oe;
 639
 640        object_ix_hashsz = nr_objects * 3;
 641        if (object_ix_hashsz < 1024)
 642                object_ix_hashsz = 1024;
 643        object_ix = xrealloc(object_ix, sizeof(int) * object_ix_hashsz);
 644        memset(object_ix, 0, sizeof(int) * object_ix_hashsz);
 645        for (i = 0, oe = objects; i < nr_objects; i++, oe++) {
 646                int ix = locate_object_entry_hash(oe->idx.sha1);
 647                if (0 <= ix)
 648                        continue;
 649                ix = -1 - ix;
 650                object_ix[ix] = i + 1;
 651        }
 652}
 653
 654static unsigned name_hash(const char *name)
 655{
 656        unsigned char c;
 657        unsigned hash = 0;
 658
 659        if (!name)
 660                return 0;
 661
 662        /*
 663         * This effectively just creates a sortable number from the
 664         * last sixteen non-whitespace characters. Last characters
 665         * count "most", so things that end in ".c" sort together.
 666         */
 667        while ((c = *name++) != 0) {
 668                if (isspace(c))
 669                        continue;
 670                hash = (hash >> 2) + (c << 24);
 671        }
 672        return hash;
 673}
 674
 675static void setup_delta_attr_check(struct git_attr_check *check)
 676{
 677        static struct git_attr *attr_delta;
 678
 679        if (!attr_delta)
 680                attr_delta = git_attr("delta", 5);
 681
 682        check[0].attr = attr_delta;
 683}
 684
 685static int no_try_delta(const char *path)
 686{
 687        struct git_attr_check check[1];
 688
 689        setup_delta_attr_check(check);
 690        if (git_checkattr(path, ARRAY_SIZE(check), check))
 691                return 0;
 692        if (ATTR_FALSE(check->value))
 693                return 1;
 694        return 0;
 695}
 696
 697static int add_object_entry(const unsigned char *sha1, enum object_type type,
 698                            const char *name, int exclude)
 699{
 700        struct object_entry *entry;
 701        struct packed_git *p, *found_pack = NULL;
 702        off_t found_offset = 0;
 703        int ix;
 704        unsigned hash = name_hash(name);
 705
 706        ix = nr_objects ? locate_object_entry_hash(sha1) : -1;
 707        if (ix >= 0) {
 708                if (exclude) {
 709                        entry = objects + object_ix[ix] - 1;
 710                        if (!entry->preferred_base)
 711                                nr_result--;
 712                        entry->preferred_base = 1;
 713                }
 714                return 0;
 715        }
 716
 717        if (!exclude && local && has_loose_object_nonlocal(sha1))
 718                return 0;
 719
 720        for (p = packed_git; p; p = p->next) {
 721                off_t offset = find_pack_entry_one(sha1, p);
 722                if (offset) {
 723                        if (!found_pack) {
 724                                found_offset = offset;
 725                                found_pack = p;
 726                        }
 727                        if (exclude)
 728                                break;
 729                        if (incremental)
 730                                return 0;
 731                        if (local && !p->pack_local)
 732                                return 0;
 733                        if (ignore_packed_keep && p->pack_local && p->pack_keep)
 734                                return 0;
 735                }
 736        }
 737
 738        if (nr_objects >= nr_alloc) {
 739                nr_alloc = (nr_alloc  + 1024) * 3 / 2;
 740                objects = xrealloc(objects, nr_alloc * sizeof(*entry));
 741        }
 742
 743        entry = objects + nr_objects++;
 744        memset(entry, 0, sizeof(*entry));
 745        hashcpy(entry->idx.sha1, sha1);
 746        entry->hash = hash;
 747        if (type)
 748                entry->type = type;
 749        if (exclude)
 750                entry->preferred_base = 1;
 751        else
 752                nr_result++;
 753        if (found_pack) {
 754                entry->in_pack = found_pack;
 755                entry->in_pack_offset = found_offset;
 756        }
 757
 758        if (object_ix_hashsz * 3 <= nr_objects * 4)
 759                rehash_objects();
 760        else
 761                object_ix[-1 - ix] = nr_objects;
 762
 763        display_progress(progress_state, nr_objects);
 764
 765        if (name && no_try_delta(name))
 766                entry->no_try_delta = 1;
 767
 768        return 1;
 769}
 770
 771struct pbase_tree_cache {
 772        unsigned char sha1[20];
 773        int ref;
 774        int temporary;
 775        void *tree_data;
 776        unsigned long tree_size;
 777};
 778
 779static struct pbase_tree_cache *(pbase_tree_cache[256]);
 780static int pbase_tree_cache_ix(const unsigned char *sha1)
 781{
 782        return sha1[0] % ARRAY_SIZE(pbase_tree_cache);
 783}
 784static int pbase_tree_cache_ix_incr(int ix)
 785{
 786        return (ix+1) % ARRAY_SIZE(pbase_tree_cache);
 787}
 788
 789static struct pbase_tree {
 790        struct pbase_tree *next;
 791        /* This is a phony "cache" entry; we are not
 792         * going to evict it nor find it through _get()
 793         * mechanism -- this is for the toplevel node that
 794         * would almost always change with any commit.
 795         */
 796        struct pbase_tree_cache pcache;
 797} *pbase_tree;
 798
 799static struct pbase_tree_cache *pbase_tree_get(const unsigned char *sha1)
 800{
 801        struct pbase_tree_cache *ent, *nent;
 802        void *data;
 803        unsigned long size;
 804        enum object_type type;
 805        int neigh;
 806        int my_ix = pbase_tree_cache_ix(sha1);
 807        int available_ix = -1;
 808
 809        /* pbase-tree-cache acts as a limited hashtable.
 810         * your object will be found at your index or within a few
 811         * slots after that slot if it is cached.
 812         */
 813        for (neigh = 0; neigh < 8; neigh++) {
 814                ent = pbase_tree_cache[my_ix];
 815                if (ent && !hashcmp(ent->sha1, sha1)) {
 816                        ent->ref++;
 817                        return ent;
 818                }
 819                else if (((available_ix < 0) && (!ent || !ent->ref)) ||
 820                         ((0 <= available_ix) &&
 821                          (!ent && pbase_tree_cache[available_ix])))
 822                        available_ix = my_ix;
 823                if (!ent)
 824                        break;
 825                my_ix = pbase_tree_cache_ix_incr(my_ix);
 826        }
 827
 828        /* Did not find one.  Either we got a bogus request or
 829         * we need to read and perhaps cache.
 830         */
 831        data = read_sha1_file(sha1, &type, &size);
 832        if (!data)
 833                return NULL;
 834        if (type != OBJ_TREE) {
 835                free(data);
 836                return NULL;
 837        }
 838
 839        /* We need to either cache or return a throwaway copy */
 840
 841        if (available_ix < 0)
 842                ent = NULL;
 843        else {
 844                ent = pbase_tree_cache[available_ix];
 845                my_ix = available_ix;
 846        }
 847
 848        if (!ent) {
 849                nent = xmalloc(sizeof(*nent));
 850                nent->temporary = (available_ix < 0);
 851        }
 852        else {
 853                /* evict and reuse */
 854                free(ent->tree_data);
 855                nent = ent;
 856        }
 857        hashcpy(nent->sha1, sha1);
 858        nent->tree_data = data;
 859        nent->tree_size = size;
 860        nent->ref = 1;
 861        if (!nent->temporary)
 862                pbase_tree_cache[my_ix] = nent;
 863        return nent;
 864}
 865
 866static void pbase_tree_put(struct pbase_tree_cache *cache)
 867{
 868        if (!cache->temporary) {
 869                cache->ref--;
 870                return;
 871        }
 872        free(cache->tree_data);
 873        free(cache);
 874}
 875
 876static int name_cmp_len(const char *name)
 877{
 878        int i;
 879        for (i = 0; name[i] && name[i] != '\n' && name[i] != '/'; i++)
 880                ;
 881        return i;
 882}
 883
 884static void add_pbase_object(struct tree_desc *tree,
 885                             const char *name,
 886                             int cmplen,
 887                             const char *fullname)
 888{
 889        struct name_entry entry;
 890        int cmp;
 891
 892        while (tree_entry(tree,&entry)) {
 893                if (S_ISGITLINK(entry.mode))
 894                        continue;
 895                cmp = tree_entry_len(entry.path, entry.sha1) != cmplen ? 1 :
 896                      memcmp(name, entry.path, cmplen);
 897                if (cmp > 0)
 898                        continue;
 899                if (cmp < 0)
 900                        return;
 901                if (name[cmplen] != '/') {
 902                        add_object_entry(entry.sha1,
 903                                         object_type(entry.mode),
 904                                         fullname, 1);
 905                        return;
 906                }
 907                if (S_ISDIR(entry.mode)) {
 908                        struct tree_desc sub;
 909                        struct pbase_tree_cache *tree;
 910                        const char *down = name+cmplen+1;
 911                        int downlen = name_cmp_len(down);
 912
 913                        tree = pbase_tree_get(entry.sha1);
 914                        if (!tree)
 915                                return;
 916                        init_tree_desc(&sub, tree->tree_data, tree->tree_size);
 917
 918                        add_pbase_object(&sub, down, downlen, fullname);
 919                        pbase_tree_put(tree);
 920                }
 921        }
 922}
 923
 924static unsigned *done_pbase_paths;
 925static int done_pbase_paths_num;
 926static int done_pbase_paths_alloc;
 927static int done_pbase_path_pos(unsigned hash)
 928{
 929        int lo = 0;
 930        int hi = done_pbase_paths_num;
 931        while (lo < hi) {
 932                int mi = (hi + lo) / 2;
 933                if (done_pbase_paths[mi] == hash)
 934                        return mi;
 935                if (done_pbase_paths[mi] < hash)
 936                        hi = mi;
 937                else
 938                        lo = mi + 1;
 939        }
 940        return -lo-1;
 941}
 942
 943static int check_pbase_path(unsigned hash)
 944{
 945        int pos = (!done_pbase_paths) ? -1 : done_pbase_path_pos(hash);
 946        if (0 <= pos)
 947                return 1;
 948        pos = -pos - 1;
 949        if (done_pbase_paths_alloc <= done_pbase_paths_num) {
 950                done_pbase_paths_alloc = alloc_nr(done_pbase_paths_alloc);
 951                done_pbase_paths = xrealloc(done_pbase_paths,
 952                                            done_pbase_paths_alloc *
 953                                            sizeof(unsigned));
 954        }
 955        done_pbase_paths_num++;
 956        if (pos < done_pbase_paths_num)
 957                memmove(done_pbase_paths + pos + 1,
 958                        done_pbase_paths + pos,
 959                        (done_pbase_paths_num - pos - 1) * sizeof(unsigned));
 960        done_pbase_paths[pos] = hash;
 961        return 0;
 962}
 963
 964static void add_preferred_base_object(const char *name)
 965{
 966        struct pbase_tree *it;
 967        int cmplen;
 968        unsigned hash = name_hash(name);
 969
 970        if (!num_preferred_base || check_pbase_path(hash))
 971                return;
 972
 973        cmplen = name_cmp_len(name);
 974        for (it = pbase_tree; it; it = it->next) {
 975                if (cmplen == 0) {
 976                        add_object_entry(it->pcache.sha1, OBJ_TREE, NULL, 1);
 977                }
 978                else {
 979                        struct tree_desc tree;
 980                        init_tree_desc(&tree, it->pcache.tree_data, it->pcache.tree_size);
 981                        add_pbase_object(&tree, name, cmplen, name);
 982                }
 983        }
 984}
 985
 986static void add_preferred_base(unsigned char *sha1)
 987{
 988        struct pbase_tree *it;
 989        void *data;
 990        unsigned long size;
 991        unsigned char tree_sha1[20];
 992
 993        if (window <= num_preferred_base++)
 994                return;
 995
 996        data = read_object_with_reference(sha1, tree_type, &size, tree_sha1);
 997        if (!data)
 998                return;
 999
1000        for (it = pbase_tree; it; it = it->next) {
1001                if (!hashcmp(it->pcache.sha1, tree_sha1)) {
1002                        free(data);
1003                        return;
1004                }
1005        }
1006
1007        it = xcalloc(1, sizeof(*it));
1008        it->next = pbase_tree;
1009        pbase_tree = it;
1010
1011        hashcpy(it->pcache.sha1, tree_sha1);
1012        it->pcache.tree_data = data;
1013        it->pcache.tree_size = size;
1014}
1015
1016static void check_object(struct object_entry *entry)
1017{
1018        if (entry->in_pack) {
1019                struct packed_git *p = entry->in_pack;
1020                struct pack_window *w_curs = NULL;
1021                const unsigned char *base_ref = NULL;
1022                struct object_entry *base_entry;
1023                unsigned long used, used_0;
1024                unsigned int avail;
1025                off_t ofs;
1026                unsigned char *buf, c;
1027
1028                buf = use_pack(p, &w_curs, entry->in_pack_offset, &avail);
1029
1030                /*
1031                 * We want in_pack_type even if we do not reuse delta
1032                 * since non-delta representations could still be reused.
1033                 */
1034                used = unpack_object_header_buffer(buf, avail,
1035                                                   &entry->in_pack_type,
1036                                                   &entry->size);
1037                if (used == 0)
1038                        goto give_up;
1039
1040                /*
1041                 * Determine if this is a delta and if so whether we can
1042                 * reuse it or not.  Otherwise let's find out as cheaply as
1043                 * possible what the actual type and size for this object is.
1044                 */
1045                switch (entry->in_pack_type) {
1046                default:
1047                        /* Not a delta hence we've already got all we need. */
1048                        entry->type = entry->in_pack_type;
1049                        entry->in_pack_header_size = used;
1050                        if (entry->type < OBJ_COMMIT || entry->type > OBJ_BLOB)
1051                                goto give_up;
1052                        unuse_pack(&w_curs);
1053                        return;
1054                case OBJ_REF_DELTA:
1055                        if (reuse_delta && !entry->preferred_base)
1056                                base_ref = use_pack(p, &w_curs,
1057                                                entry->in_pack_offset + used, NULL);
1058                        entry->in_pack_header_size = used + 20;
1059                        break;
1060                case OBJ_OFS_DELTA:
1061                        buf = use_pack(p, &w_curs,
1062                                       entry->in_pack_offset + used, NULL);
1063                        used_0 = 0;
1064                        c = buf[used_0++];
1065                        ofs = c & 127;
1066                        while (c & 128) {
1067                                ofs += 1;
1068                                if (!ofs || MSB(ofs, 7)) {
1069                                        error("delta base offset overflow in pack for %s",
1070                                              sha1_to_hex(entry->idx.sha1));
1071                                        goto give_up;
1072                                }
1073                                c = buf[used_0++];
1074                                ofs = (ofs << 7) + (c & 127);
1075                        }
1076                        ofs = entry->in_pack_offset - ofs;
1077                        if (ofs <= 0 || ofs >= entry->in_pack_offset) {
1078                                error("delta base offset out of bound for %s",
1079                                      sha1_to_hex(entry->idx.sha1));
1080                                goto give_up;
1081                        }
1082                        if (reuse_delta && !entry->preferred_base) {
1083                                struct revindex_entry *revidx;
1084                                revidx = find_pack_revindex(p, ofs);
1085                                if (!revidx)
1086                                        goto give_up;
1087                                base_ref = nth_packed_object_sha1(p, revidx->nr);
1088                        }
1089                        entry->in_pack_header_size = used + used_0;
1090                        break;
1091                }
1092
1093                if (base_ref && (base_entry = locate_object_entry(base_ref))) {
1094                        /*
1095                         * If base_ref was set above that means we wish to
1096                         * reuse delta data, and we even found that base
1097                         * in the list of objects we want to pack. Goodie!
1098                         *
1099                         * Depth value does not matter - find_deltas() will
1100                         * never consider reused delta as the base object to
1101                         * deltify other objects against, in order to avoid
1102                         * circular deltas.
1103                         */
1104                        entry->type = entry->in_pack_type;
1105                        entry->delta = base_entry;
1106                        entry->delta_size = entry->size;
1107                        entry->delta_sibling = base_entry->delta_child;
1108                        base_entry->delta_child = entry;
1109                        unuse_pack(&w_curs);
1110                        return;
1111                }
1112
1113                if (entry->type) {
1114                        /*
1115                         * This must be a delta and we already know what the
1116                         * final object type is.  Let's extract the actual
1117                         * object size from the delta header.
1118                         */
1119                        entry->size = get_size_from_delta(p, &w_curs,
1120                                        entry->in_pack_offset + entry->in_pack_header_size);
1121                        if (entry->size == 0)
1122                                goto give_up;
1123                        unuse_pack(&w_curs);
1124                        return;
1125                }
1126
1127                /*
1128                 * No choice but to fall back to the recursive delta walk
1129                 * with sha1_object_info() to find about the object type
1130                 * at this point...
1131                 */
1132                give_up:
1133                unuse_pack(&w_curs);
1134        }
1135
1136        entry->type = sha1_object_info(entry->idx.sha1, &entry->size);
1137        /*
1138         * The error condition is checked in prepare_pack().  This is
1139         * to permit a missing preferred base object to be ignored
1140         * as a preferred base.  Doing so can result in a larger
1141         * pack file, but the transfer will still take place.
1142         */
1143}
1144
1145static int pack_offset_sort(const void *_a, const void *_b)
1146{
1147        const struct object_entry *a = *(struct object_entry **)_a;
1148        const struct object_entry *b = *(struct object_entry **)_b;
1149
1150        /* avoid filesystem trashing with loose objects */
1151        if (!a->in_pack && !b->in_pack)
1152                return hashcmp(a->idx.sha1, b->idx.sha1);
1153
1154        if (a->in_pack < b->in_pack)
1155                return -1;
1156        if (a->in_pack > b->in_pack)
1157                return 1;
1158        return a->in_pack_offset < b->in_pack_offset ? -1 :
1159                        (a->in_pack_offset > b->in_pack_offset);
1160}
1161
1162static void get_object_details(void)
1163{
1164        uint32_t i;
1165        struct object_entry **sorted_by_offset;
1166
1167        sorted_by_offset = xcalloc(nr_objects, sizeof(struct object_entry *));
1168        for (i = 0; i < nr_objects; i++)
1169                sorted_by_offset[i] = objects + i;
1170        qsort(sorted_by_offset, nr_objects, sizeof(*sorted_by_offset), pack_offset_sort);
1171
1172        for (i = 0; i < nr_objects; i++)
1173                check_object(sorted_by_offset[i]);
1174
1175        free(sorted_by_offset);
1176}
1177
1178/*
1179 * We search for deltas in a list sorted by type, by filename hash, and then
1180 * by size, so that we see progressively smaller and smaller files.
1181 * That's because we prefer deltas to be from the bigger file
1182 * to the smaller -- deletes are potentially cheaper, but perhaps
1183 * more importantly, the bigger file is likely the more recent
1184 * one.  The deepest deltas are therefore the oldest objects which are
1185 * less susceptible to be accessed often.
1186 */
1187static int type_size_sort(const void *_a, const void *_b)
1188{
1189        const struct object_entry *a = *(struct object_entry **)_a;
1190        const struct object_entry *b = *(struct object_entry **)_b;
1191
1192        if (a->type > b->type)
1193                return -1;
1194        if (a->type < b->type)
1195                return 1;
1196        if (a->hash > b->hash)
1197                return -1;
1198        if (a->hash < b->hash)
1199                return 1;
1200        if (a->preferred_base > b->preferred_base)
1201                return -1;
1202        if (a->preferred_base < b->preferred_base)
1203                return 1;
1204        if (a->size > b->size)
1205                return -1;
1206        if (a->size < b->size)
1207                return 1;
1208        return a < b ? -1 : (a > b);  /* newest first */
1209}
1210
1211struct unpacked {
1212        struct object_entry *entry;
1213        void *data;
1214        struct delta_index *index;
1215        unsigned depth;
1216};
1217
1218static int delta_cacheable(unsigned long src_size, unsigned long trg_size,
1219                           unsigned long delta_size)
1220{
1221        if (max_delta_cache_size && delta_cache_size + delta_size > max_delta_cache_size)
1222                return 0;
1223
1224        if (delta_size < cache_max_small_delta_size)
1225                return 1;
1226
1227        /* cache delta, if objects are large enough compared to delta size */
1228        if ((src_size >> 20) + (trg_size >> 21) > (delta_size >> 10))
1229                return 1;
1230
1231        return 0;
1232}
1233
1234#ifdef THREADED_DELTA_SEARCH
1235
1236static pthread_mutex_t read_mutex = PTHREAD_MUTEX_INITIALIZER;
1237#define read_lock()             pthread_mutex_lock(&read_mutex)
1238#define read_unlock()           pthread_mutex_unlock(&read_mutex)
1239
1240static pthread_mutex_t cache_mutex = PTHREAD_MUTEX_INITIALIZER;
1241#define cache_lock()            pthread_mutex_lock(&cache_mutex)
1242#define cache_unlock()          pthread_mutex_unlock(&cache_mutex)
1243
1244static pthread_mutex_t progress_mutex = PTHREAD_MUTEX_INITIALIZER;
1245#define progress_lock()         pthread_mutex_lock(&progress_mutex)
1246#define progress_unlock()       pthread_mutex_unlock(&progress_mutex)
1247
1248#else
1249
1250#define read_lock()             (void)0
1251#define read_unlock()           (void)0
1252#define cache_lock()            (void)0
1253#define cache_unlock()          (void)0
1254#define progress_lock()         (void)0
1255#define progress_unlock()       (void)0
1256
1257#endif
1258
1259static int try_delta(struct unpacked *trg, struct unpacked *src,
1260                     unsigned max_depth, unsigned long *mem_usage)
1261{
1262        struct object_entry *trg_entry = trg->entry;
1263        struct object_entry *src_entry = src->entry;
1264        unsigned long trg_size, src_size, delta_size, sizediff, max_size, sz;
1265        unsigned ref_depth;
1266        enum object_type type;
1267        void *delta_buf;
1268
1269        /* Don't bother doing diffs between different types */
1270        if (trg_entry->type != src_entry->type)
1271                return -1;
1272
1273        /*
1274         * We do not bother to try a delta that we discarded
1275         * on an earlier try, but only when reusing delta data.
1276         */
1277        if (reuse_delta && trg_entry->in_pack &&
1278            trg_entry->in_pack == src_entry->in_pack &&
1279            trg_entry->in_pack_type != OBJ_REF_DELTA &&
1280            trg_entry->in_pack_type != OBJ_OFS_DELTA)
1281                return 0;
1282
1283        /* Let's not bust the allowed depth. */
1284        if (src->depth >= max_depth)
1285                return 0;
1286
1287        /* Now some size filtering heuristics. */
1288        trg_size = trg_entry->size;
1289        if (!trg_entry->delta) {
1290                max_size = trg_size/2 - 20;
1291                ref_depth = 1;
1292        } else {
1293                max_size = trg_entry->delta_size;
1294                ref_depth = trg->depth;
1295        }
1296        max_size = (uint64_t)max_size * (max_depth - src->depth) /
1297                                                (max_depth - ref_depth + 1);
1298        if (max_size == 0)
1299                return 0;
1300        src_size = src_entry->size;
1301        sizediff = src_size < trg_size ? trg_size - src_size : 0;
1302        if (sizediff >= max_size)
1303                return 0;
1304        if (trg_size < src_size / 32)
1305                return 0;
1306
1307        /* Load data if not already done */
1308        if (!trg->data) {
1309                read_lock();
1310                trg->data = read_sha1_file(trg_entry->idx.sha1, &type, &sz);
1311                read_unlock();
1312                if (!trg->data)
1313                        die("object %s cannot be read",
1314                            sha1_to_hex(trg_entry->idx.sha1));
1315                if (sz != trg_size)
1316                        die("object %s inconsistent object length (%lu vs %lu)",
1317                            sha1_to_hex(trg_entry->idx.sha1), sz, trg_size);
1318                *mem_usage += sz;
1319        }
1320        if (!src->data) {
1321                read_lock();
1322                src->data = read_sha1_file(src_entry->idx.sha1, &type, &sz);
1323                read_unlock();
1324                if (!src->data)
1325                        die("object %s cannot be read",
1326                            sha1_to_hex(src_entry->idx.sha1));
1327                if (sz != src_size)
1328                        die("object %s inconsistent object length (%lu vs %lu)",
1329                            sha1_to_hex(src_entry->idx.sha1), sz, src_size);
1330                *mem_usage += sz;
1331        }
1332        if (!src->index) {
1333                src->index = create_delta_index(src->data, src_size);
1334                if (!src->index) {
1335                        static int warned = 0;
1336                        if (!warned++)
1337                                warning("suboptimal pack - out of memory");
1338                        return 0;
1339                }
1340                *mem_usage += sizeof_delta_index(src->index);
1341        }
1342
1343        delta_buf = create_delta(src->index, trg->data, trg_size, &delta_size, max_size);
1344        if (!delta_buf)
1345                return 0;
1346
1347        if (trg_entry->delta) {
1348                /* Prefer only shallower same-sized deltas. */
1349                if (delta_size == trg_entry->delta_size &&
1350                    src->depth + 1 >= trg->depth) {
1351                        free(delta_buf);
1352                        return 0;
1353                }
1354        }
1355
1356        /*
1357         * Handle memory allocation outside of the cache
1358         * accounting lock.  Compiler will optimize the strangeness
1359         * away when THREADED_DELTA_SEARCH is not defined.
1360         */
1361        free(trg_entry->delta_data);
1362        cache_lock();
1363        if (trg_entry->delta_data) {
1364                delta_cache_size -= trg_entry->delta_size;
1365                trg_entry->delta_data = NULL;
1366        }
1367        if (delta_cacheable(src_size, trg_size, delta_size)) {
1368                delta_cache_size += delta_size;
1369                cache_unlock();
1370                trg_entry->delta_data = xrealloc(delta_buf, delta_size);
1371        } else {
1372                cache_unlock();
1373                free(delta_buf);
1374        }
1375
1376        trg_entry->delta = src_entry;
1377        trg_entry->delta_size = delta_size;
1378        trg->depth = src->depth + 1;
1379
1380        return 1;
1381}
1382
1383static unsigned int check_delta_limit(struct object_entry *me, unsigned int n)
1384{
1385        struct object_entry *child = me->delta_child;
1386        unsigned int m = n;
1387        while (child) {
1388                unsigned int c = check_delta_limit(child, n + 1);
1389                if (m < c)
1390                        m = c;
1391                child = child->delta_sibling;
1392        }
1393        return m;
1394}
1395
1396static unsigned long free_unpacked(struct unpacked *n)
1397{
1398        unsigned long freed_mem = sizeof_delta_index(n->index);
1399        free_delta_index(n->index);
1400        n->index = NULL;
1401        if (n->data) {
1402                freed_mem += n->entry->size;
1403                free(n->data);
1404                n->data = NULL;
1405        }
1406        n->entry = NULL;
1407        n->depth = 0;
1408        return freed_mem;
1409}
1410
1411static void find_deltas(struct object_entry **list, unsigned *list_size,
1412                        int window, int depth, unsigned *processed)
1413{
1414        uint32_t i, idx = 0, count = 0;
1415        struct unpacked *array;
1416        unsigned long mem_usage = 0;
1417
1418        array = xcalloc(window, sizeof(struct unpacked));
1419
1420        for (;;) {
1421                struct object_entry *entry;
1422                struct unpacked *n = array + idx;
1423                int j, max_depth, best_base = -1;
1424
1425                progress_lock();
1426                if (!*list_size) {
1427                        progress_unlock();
1428                        break;
1429                }
1430                entry = *list++;
1431                (*list_size)--;
1432                if (!entry->preferred_base) {
1433                        (*processed)++;
1434                        display_progress(progress_state, *processed);
1435                }
1436                progress_unlock();
1437
1438                mem_usage -= free_unpacked(n);
1439                n->entry = entry;
1440
1441                while (window_memory_limit &&
1442                       mem_usage > window_memory_limit &&
1443                       count > 1) {
1444                        uint32_t tail = (idx + window - count) % window;
1445                        mem_usage -= free_unpacked(array + tail);
1446                        count--;
1447                }
1448
1449                /* We do not compute delta to *create* objects we are not
1450                 * going to pack.
1451                 */
1452                if (entry->preferred_base)
1453                        goto next;
1454
1455                /*
1456                 * If the current object is at pack edge, take the depth the
1457                 * objects that depend on the current object into account
1458                 * otherwise they would become too deep.
1459                 */
1460                max_depth = depth;
1461                if (entry->delta_child) {
1462                        max_depth -= check_delta_limit(entry, 0);
1463                        if (max_depth <= 0)
1464                                goto next;
1465                }
1466
1467                j = window;
1468                while (--j > 0) {
1469                        int ret;
1470                        uint32_t other_idx = idx + j;
1471                        struct unpacked *m;
1472                        if (other_idx >= window)
1473                                other_idx -= window;
1474                        m = array + other_idx;
1475                        if (!m->entry)
1476                                break;
1477                        ret = try_delta(n, m, max_depth, &mem_usage);
1478                        if (ret < 0)
1479                                break;
1480                        else if (ret > 0)
1481                                best_base = other_idx;
1482                }
1483
1484                /*
1485                 * If we decided to cache the delta data, then it is best
1486                 * to compress it right away.  First because we have to do
1487                 * it anyway, and doing it here while we're threaded will
1488                 * save a lot of time in the non threaded write phase,
1489                 * as well as allow for caching more deltas within
1490                 * the same cache size limit.
1491                 * ...
1492                 * But only if not writing to stdout, since in that case
1493                 * the network is most likely throttling writes anyway,
1494                 * and therefore it is best to go to the write phase ASAP
1495                 * instead, as we can afford spending more time compressing
1496                 * between writes at that moment.
1497                 */
1498                if (entry->delta_data && !pack_to_stdout) {
1499                        entry->z_delta_size = do_compress(&entry->delta_data,
1500                                                          entry->delta_size);
1501                        cache_lock();
1502                        delta_cache_size -= entry->delta_size;
1503                        delta_cache_size += entry->z_delta_size;
1504                        cache_unlock();
1505                }
1506
1507                /* if we made n a delta, and if n is already at max
1508                 * depth, leaving it in the window is pointless.  we
1509                 * should evict it first.
1510                 */
1511                if (entry->delta && max_depth <= n->depth)
1512                        continue;
1513
1514                /*
1515                 * Move the best delta base up in the window, after the
1516                 * currently deltified object, to keep it longer.  It will
1517                 * be the first base object to be attempted next.
1518                 */
1519                if (entry->delta) {
1520                        struct unpacked swap = array[best_base];
1521                        int dist = (window + idx - best_base) % window;
1522                        int dst = best_base;
1523                        while (dist--) {
1524                                int src = (dst + 1) % window;
1525                                array[dst] = array[src];
1526                                dst = src;
1527                        }
1528                        array[dst] = swap;
1529                }
1530
1531                next:
1532                idx++;
1533                if (count + 1 < window)
1534                        count++;
1535                if (idx >= window)
1536                        idx = 0;
1537        }
1538
1539        for (i = 0; i < window; ++i) {
1540                free_delta_index(array[i].index);
1541                free(array[i].data);
1542        }
1543        free(array);
1544}
1545
1546#ifdef THREADED_DELTA_SEARCH
1547
1548/*
1549 * The main thread waits on the condition that (at least) one of the workers
1550 * has stopped working (which is indicated in the .working member of
1551 * struct thread_params).
1552 * When a work thread has completed its work, it sets .working to 0 and
1553 * signals the main thread and waits on the condition that .data_ready
1554 * becomes 1.
1555 */
1556
1557struct thread_params {
1558        pthread_t thread;
1559        struct object_entry **list;
1560        unsigned list_size;
1561        unsigned remaining;
1562        int window;
1563        int depth;
1564        int working;
1565        int data_ready;
1566        pthread_mutex_t mutex;
1567        pthread_cond_t cond;
1568        unsigned *processed;
1569};
1570
1571static pthread_cond_t progress_cond = PTHREAD_COND_INITIALIZER;
1572
1573static void *threaded_find_deltas(void *arg)
1574{
1575        struct thread_params *me = arg;
1576
1577        while (me->remaining) {
1578                find_deltas(me->list, &me->remaining,
1579                            me->window, me->depth, me->processed);
1580
1581                progress_lock();
1582                me->working = 0;
1583                pthread_cond_signal(&progress_cond);
1584                progress_unlock();
1585
1586                /*
1587                 * We must not set ->data_ready before we wait on the
1588                 * condition because the main thread may have set it to 1
1589                 * before we get here. In order to be sure that new
1590                 * work is available if we see 1 in ->data_ready, it
1591                 * was initialized to 0 before this thread was spawned
1592                 * and we reset it to 0 right away.
1593                 */
1594                pthread_mutex_lock(&me->mutex);
1595                while (!me->data_ready)
1596                        pthread_cond_wait(&me->cond, &me->mutex);
1597                me->data_ready = 0;
1598                pthread_mutex_unlock(&me->mutex);
1599        }
1600        /* leave ->working 1 so that this doesn't get more work assigned */
1601        return NULL;
1602}
1603
1604static void ll_find_deltas(struct object_entry **list, unsigned list_size,
1605                           int window, int depth, unsigned *processed)
1606{
1607        struct thread_params p[delta_search_threads];
1608        int i, ret, active_threads = 0;
1609
1610        if (delta_search_threads <= 1) {
1611                find_deltas(list, &list_size, window, depth, processed);
1612                return;
1613        }
1614        if (progress > pack_to_stdout)
1615                fprintf(stderr, "Delta compression using up to %d threads.\n",
1616                                delta_search_threads);
1617
1618        /* Partition the work amongst work threads. */
1619        for (i = 0; i < delta_search_threads; i++) {
1620                unsigned sub_size = list_size / (delta_search_threads - i);
1621
1622                /* don't use too small segments or no deltas will be found */
1623                if (sub_size < 2*window && i+1 < delta_search_threads)
1624                        sub_size = 0;
1625
1626                p[i].window = window;
1627                p[i].depth = depth;
1628                p[i].processed = processed;
1629                p[i].working = 1;
1630                p[i].data_ready = 0;
1631
1632                /* try to split chunks on "path" boundaries */
1633                while (sub_size && sub_size < list_size &&
1634                       list[sub_size]->hash &&
1635                       list[sub_size]->hash == list[sub_size-1]->hash)
1636                        sub_size++;
1637
1638                p[i].list = list;
1639                p[i].list_size = sub_size;
1640                p[i].remaining = sub_size;
1641
1642                list += sub_size;
1643                list_size -= sub_size;
1644        }
1645
1646        /* Start work threads. */
1647        for (i = 0; i < delta_search_threads; i++) {
1648                if (!p[i].list_size)
1649                        continue;
1650                pthread_mutex_init(&p[i].mutex, NULL);
1651                pthread_cond_init(&p[i].cond, NULL);
1652                ret = pthread_create(&p[i].thread, NULL,
1653                                     threaded_find_deltas, &p[i]);
1654                if (ret)
1655                        die("unable to create thread: %s", strerror(ret));
1656                active_threads++;
1657        }
1658
1659        /*
1660         * Now let's wait for work completion.  Each time a thread is done
1661         * with its work, we steal half of the remaining work from the
1662         * thread with the largest number of unprocessed objects and give
1663         * it to that newly idle thread.  This ensure good load balancing
1664         * until the remaining object list segments are simply too short
1665         * to be worth splitting anymore.
1666         */
1667        while (active_threads) {
1668                struct thread_params *target = NULL;
1669                struct thread_params *victim = NULL;
1670                unsigned sub_size = 0;
1671
1672                progress_lock();
1673                for (;;) {
1674                        for (i = 0; !target && i < delta_search_threads; i++)
1675                                if (!p[i].working)
1676                                        target = &p[i];
1677                        if (target)
1678                                break;
1679                        pthread_cond_wait(&progress_cond, &progress_mutex);
1680                }
1681
1682                for (i = 0; i < delta_search_threads; i++)
1683                        if (p[i].remaining > 2*window &&
1684                            (!victim || victim->remaining < p[i].remaining))
1685                                victim = &p[i];
1686                if (victim) {
1687                        sub_size = victim->remaining / 2;
1688                        list = victim->list + victim->list_size - sub_size;
1689                        while (sub_size && list[0]->hash &&
1690                               list[0]->hash == list[-1]->hash) {
1691                                list++;
1692                                sub_size--;
1693                        }
1694                        if (!sub_size) {
1695                                /*
1696                                 * It is possible for some "paths" to have
1697                                 * so many objects that no hash boundary
1698                                 * might be found.  Let's just steal the
1699                                 * exact half in that case.
1700                                 */
1701                                sub_size = victim->remaining / 2;
1702                                list -= sub_size;
1703                        }
1704                        target->list = list;
1705                        victim->list_size -= sub_size;
1706                        victim->remaining -= sub_size;
1707                }
1708                target->list_size = sub_size;
1709                target->remaining = sub_size;
1710                target->working = 1;
1711                progress_unlock();
1712
1713                pthread_mutex_lock(&target->mutex);
1714                target->data_ready = 1;
1715                pthread_cond_signal(&target->cond);
1716                pthread_mutex_unlock(&target->mutex);
1717
1718                if (!sub_size) {
1719                        pthread_join(target->thread, NULL);
1720                        pthread_cond_destroy(&target->cond);
1721                        pthread_mutex_destroy(&target->mutex);
1722                        active_threads--;
1723                }
1724        }
1725}
1726
1727#else
1728#define ll_find_deltas(l, s, w, d, p)   find_deltas(l, &s, w, d, p)
1729#endif
1730
1731static int add_ref_tag(const char *path, const unsigned char *sha1, int flag, void *cb_data)
1732{
1733        unsigned char peeled[20];
1734
1735        if (!prefixcmp(path, "refs/tags/") && /* is a tag? */
1736            !peel_ref(path, peeled)        && /* peelable? */
1737            !is_null_sha1(peeled)          && /* annotated tag? */
1738            locate_object_entry(peeled))      /* object packed? */
1739                add_object_entry(sha1, OBJ_TAG, NULL, 0);
1740        return 0;
1741}
1742
1743static void prepare_pack(int window, int depth)
1744{
1745        struct object_entry **delta_list;
1746        uint32_t i, nr_deltas;
1747        unsigned n;
1748
1749        get_object_details();
1750
1751        /*
1752         * If we're locally repacking then we need to be doubly careful
1753         * from now on in order to make sure no stealth corruption gets
1754         * propagated to the new pack.  Clients receiving streamed packs
1755         * should validate everything they get anyway so no need to incur
1756         * the additional cost here in that case.
1757         */
1758        if (!pack_to_stdout)
1759                do_check_packed_object_crc = 1;
1760
1761        if (!nr_objects || !window || !depth)
1762                return;
1763
1764        delta_list = xmalloc(nr_objects * sizeof(*delta_list));
1765        nr_deltas = n = 0;
1766
1767        for (i = 0; i < nr_objects; i++) {
1768                struct object_entry *entry = objects + i;
1769
1770                if (entry->delta)
1771                        /* This happens if we decided to reuse existing
1772                         * delta from a pack.  "reuse_delta &&" is implied.
1773                         */
1774                        continue;
1775
1776                if (entry->size < 50)
1777                        continue;
1778
1779                if (entry->no_try_delta)
1780                        continue;
1781
1782                if (!entry->preferred_base) {
1783                        nr_deltas++;
1784                        if (entry->type < 0)
1785                                die("unable to get type of object %s",
1786                                    sha1_to_hex(entry->idx.sha1));
1787                } else {
1788                        if (entry->type < 0) {
1789                                /*
1790                                 * This object is not found, but we
1791                                 * don't have to include it anyway.
1792                                 */
1793                                continue;
1794                        }
1795                }
1796
1797                delta_list[n++] = entry;
1798        }
1799
1800        if (nr_deltas && n > 1) {
1801                unsigned nr_done = 0;
1802                if (progress)
1803                        progress_state = start_progress("Compressing objects",
1804                                                        nr_deltas);
1805                qsort(delta_list, n, sizeof(*delta_list), type_size_sort);
1806                ll_find_deltas(delta_list, n, window+1, depth, &nr_done);
1807                stop_progress(&progress_state);
1808                if (nr_done != nr_deltas)
1809                        die("inconsistency with delta count");
1810        }
1811        free(delta_list);
1812}
1813
1814static int git_pack_config(const char *k, const char *v, void *cb)
1815{
1816        if(!strcmp(k, "pack.window")) {
1817                window = git_config_int(k, v);
1818                return 0;
1819        }
1820        if (!strcmp(k, "pack.windowmemory")) {
1821                window_memory_limit = git_config_ulong(k, v);
1822                return 0;
1823        }
1824        if (!strcmp(k, "pack.depth")) {
1825                depth = git_config_int(k, v);
1826                return 0;
1827        }
1828        if (!strcmp(k, "pack.compression")) {
1829                int level = git_config_int(k, v);
1830                if (level == -1)
1831                        level = Z_DEFAULT_COMPRESSION;
1832                else if (level < 0 || level > Z_BEST_COMPRESSION)
1833                        die("bad pack compression level %d", level);
1834                pack_compression_level = level;
1835                pack_compression_seen = 1;
1836                return 0;
1837        }
1838        if (!strcmp(k, "pack.deltacachesize")) {
1839                max_delta_cache_size = git_config_int(k, v);
1840                return 0;
1841        }
1842        if (!strcmp(k, "pack.deltacachelimit")) {
1843                cache_max_small_delta_size = git_config_int(k, v);
1844                return 0;
1845        }
1846        if (!strcmp(k, "pack.threads")) {
1847                delta_search_threads = git_config_int(k, v);
1848                if (delta_search_threads < 0)
1849                        die("invalid number of threads specified (%d)",
1850                            delta_search_threads);
1851#ifndef THREADED_DELTA_SEARCH
1852                if (delta_search_threads != 1)
1853                        warning("no threads support, ignoring %s", k);
1854#endif
1855                return 0;
1856        }
1857        if (!strcmp(k, "pack.indexversion")) {
1858                pack_idx_default_version = git_config_int(k, v);
1859                if (pack_idx_default_version > 2)
1860                        die("bad pack.indexversion=%"PRIu32,
1861                                pack_idx_default_version);
1862                return 0;
1863        }
1864        if (!strcmp(k, "pack.packsizelimit")) {
1865                pack_size_limit_cfg = git_config_ulong(k, v);
1866                return 0;
1867        }
1868        return git_default_config(k, v, cb);
1869}
1870
1871static void read_object_list_from_stdin(void)
1872{
1873        char line[40 + 1 + PATH_MAX + 2];
1874        unsigned char sha1[20];
1875
1876        for (;;) {
1877                if (!fgets(line, sizeof(line), stdin)) {
1878                        if (feof(stdin))
1879                                break;
1880                        if (!ferror(stdin))
1881                                die("fgets returned NULL, not EOF, not error!");
1882                        if (errno != EINTR)
1883                                die("fgets: %s", strerror(errno));
1884                        clearerr(stdin);
1885                        continue;
1886                }
1887                if (line[0] == '-') {
1888                        if (get_sha1_hex(line+1, sha1))
1889                                die("expected edge sha1, got garbage:\n %s",
1890                                    line);
1891                        add_preferred_base(sha1);
1892                        continue;
1893                }
1894                if (get_sha1_hex(line, sha1))
1895                        die("expected sha1, got garbage:\n %s", line);
1896
1897                add_preferred_base_object(line+41);
1898                add_object_entry(sha1, 0, line+41, 0);
1899        }
1900}
1901
1902#define OBJECT_ADDED (1u<<20)
1903
1904static void show_commit(struct commit *commit, void *data)
1905{
1906        add_object_entry(commit->object.sha1, OBJ_COMMIT, NULL, 0);
1907        commit->object.flags |= OBJECT_ADDED;
1908}
1909
1910static void show_object(struct object_array_entry *p, void *data)
1911{
1912        add_preferred_base_object(p->name);
1913        add_object_entry(p->item->sha1, p->item->type, p->name, 0);
1914        p->item->flags |= OBJECT_ADDED;
1915        free((char *)p->name);
1916        p->name = NULL;
1917}
1918
1919static void show_edge(struct commit *commit)
1920{
1921        add_preferred_base(commit->object.sha1);
1922}
1923
1924struct in_pack_object {
1925        off_t offset;
1926        struct object *object;
1927};
1928
1929struct in_pack {
1930        int alloc;
1931        int nr;
1932        struct in_pack_object *array;
1933};
1934
1935static void mark_in_pack_object(struct object *object, struct packed_git *p, struct in_pack *in_pack)
1936{
1937        in_pack->array[in_pack->nr].offset = find_pack_entry_one(object->sha1, p);
1938        in_pack->array[in_pack->nr].object = object;
1939        in_pack->nr++;
1940}
1941
1942/*
1943 * Compare the objects in the offset order, in order to emulate the
1944 * "git rev-list --objects" output that produced the pack originally.
1945 */
1946static int ofscmp(const void *a_, const void *b_)
1947{
1948        struct in_pack_object *a = (struct in_pack_object *)a_;
1949        struct in_pack_object *b = (struct in_pack_object *)b_;
1950
1951        if (a->offset < b->offset)
1952                return -1;
1953        else if (a->offset > b->offset)
1954                return 1;
1955        else
1956                return hashcmp(a->object->sha1, b->object->sha1);
1957}
1958
1959static void add_objects_in_unpacked_packs(struct rev_info *revs)
1960{
1961        struct packed_git *p;
1962        struct in_pack in_pack;
1963        uint32_t i;
1964
1965        memset(&in_pack, 0, sizeof(in_pack));
1966
1967        for (p = packed_git; p; p = p->next) {
1968                const unsigned char *sha1;
1969                struct object *o;
1970
1971                if (!p->pack_local || p->pack_keep)
1972                        continue;
1973                if (open_pack_index(p))
1974                        die("cannot open pack index");
1975
1976                ALLOC_GROW(in_pack.array,
1977                           in_pack.nr + p->num_objects,
1978                           in_pack.alloc);
1979
1980                for (i = 0; i < p->num_objects; i++) {
1981                        sha1 = nth_packed_object_sha1(p, i);
1982                        o = lookup_unknown_object(sha1);
1983                        if (!(o->flags & OBJECT_ADDED))
1984                                mark_in_pack_object(o, p, &in_pack);
1985                        o->flags |= OBJECT_ADDED;
1986                }
1987        }
1988
1989        if (in_pack.nr) {
1990                qsort(in_pack.array, in_pack.nr, sizeof(in_pack.array[0]),
1991                      ofscmp);
1992                for (i = 0; i < in_pack.nr; i++) {
1993                        struct object *o = in_pack.array[i].object;
1994                        add_object_entry(o->sha1, o->type, "", 0);
1995                }
1996        }
1997        free(in_pack.array);
1998}
1999
2000static int has_sha1_pack_kept_or_nonlocal(const unsigned char *sha1)
2001{
2002        static struct packed_git *last_found = (void *)1;
2003        struct packed_git *p;
2004
2005        p = (last_found != (void *)1) ? last_found : packed_git;
2006
2007        while (p) {
2008                if ((!p->pack_local || p->pack_keep) &&
2009                        find_pack_entry_one(sha1, p)) {
2010                        last_found = p;
2011                        return 1;
2012                }
2013                if (p == last_found)
2014                        p = packed_git;
2015                else
2016                        p = p->next;
2017                if (p == last_found)
2018                        p = p->next;
2019        }
2020        return 0;
2021}
2022
2023static void loosen_unused_packed_objects(struct rev_info *revs)
2024{
2025        struct packed_git *p;
2026        uint32_t i;
2027        const unsigned char *sha1;
2028
2029        for (p = packed_git; p; p = p->next) {
2030                if (!p->pack_local || p->pack_keep)
2031                        continue;
2032
2033                if (open_pack_index(p))
2034                        die("cannot open pack index");
2035
2036                for (i = 0; i < p->num_objects; i++) {
2037                        sha1 = nth_packed_object_sha1(p, i);
2038                        if (!locate_object_entry(sha1) &&
2039                                !has_sha1_pack_kept_or_nonlocal(sha1))
2040                                if (force_object_loose(sha1, p->mtime))
2041                                        die("unable to force loose object");
2042                }
2043        }
2044}
2045
2046static void get_object_list(int ac, const char **av)
2047{
2048        struct rev_info revs;
2049        char line[1000];
2050        int flags = 0;
2051
2052        init_revisions(&revs, NULL);
2053        save_commit_buffer = 0;
2054        setup_revisions(ac, av, &revs, NULL);
2055
2056        while (fgets(line, sizeof(line), stdin) != NULL) {
2057                int len = strlen(line);
2058                if (len && line[len - 1] == '\n')
2059                        line[--len] = 0;
2060                if (!len)
2061                        break;
2062                if (*line == '-') {
2063                        if (!strcmp(line, "--not")) {
2064                                flags ^= UNINTERESTING;
2065                                continue;
2066                        }
2067                        die("not a rev '%s'", line);
2068                }
2069                if (handle_revision_arg(line, &revs, flags, 1))
2070                        die("bad revision '%s'", line);
2071        }
2072
2073        if (prepare_revision_walk(&revs))
2074                die("revision walk setup failed");
2075        mark_edges_uninteresting(revs.commits, &revs, show_edge);
2076        traverse_commit_list(&revs, show_commit, show_object, NULL);
2077
2078        if (keep_unreachable)
2079                add_objects_in_unpacked_packs(&revs);
2080        if (unpack_unreachable)
2081                loosen_unused_packed_objects(&revs);
2082}
2083
2084static int adjust_perm(const char *path, mode_t mode)
2085{
2086        if (chmod(path, mode))
2087                return -1;
2088        return adjust_shared_perm(path);
2089}
2090
2091int cmd_pack_objects(int argc, const char **argv, const char *prefix)
2092{
2093        int use_internal_rev_list = 0;
2094        int thin = 0;
2095        uint32_t i;
2096        const char **rp_av;
2097        int rp_ac_alloc = 64;
2098        int rp_ac;
2099
2100        rp_av = xcalloc(rp_ac_alloc, sizeof(*rp_av));
2101
2102        rp_av[0] = "pack-objects";
2103        rp_av[1] = "--objects"; /* --thin will make it --objects-edge */
2104        rp_ac = 2;
2105
2106        git_config(git_pack_config, NULL);
2107        if (!pack_compression_seen && core_compression_seen)
2108                pack_compression_level = core_compression_level;
2109
2110        progress = isatty(2);
2111        for (i = 1; i < argc; i++) {
2112                const char *arg = argv[i];
2113
2114                if (*arg != '-')
2115                        break;
2116
2117                if (!strcmp("--non-empty", arg)) {
2118                        non_empty = 1;
2119                        continue;
2120                }
2121                if (!strcmp("--local", arg)) {
2122                        local = 1;
2123                        continue;
2124                }
2125                if (!strcmp("--incremental", arg)) {
2126                        incremental = 1;
2127                        continue;
2128                }
2129                if (!strcmp("--honor-pack-keep", arg)) {
2130                        ignore_packed_keep = 1;
2131                        continue;
2132                }
2133                if (!prefixcmp(arg, "--compression=")) {
2134                        char *end;
2135                        int level = strtoul(arg+14, &end, 0);
2136                        if (!arg[14] || *end)
2137                                usage(pack_usage);
2138                        if (level == -1)
2139                                level = Z_DEFAULT_COMPRESSION;
2140                        else if (level < 0 || level > Z_BEST_COMPRESSION)
2141                                die("bad pack compression level %d", level);
2142                        pack_compression_level = level;
2143                        continue;
2144                }
2145                if (!prefixcmp(arg, "--max-pack-size=")) {
2146                        char *end;
2147                        pack_size_limit_cfg = 0;
2148                        pack_size_limit = strtoul(arg+16, &end, 0) * 1024 * 1024;
2149                        if (!arg[16] || *end)
2150                                usage(pack_usage);
2151                        continue;
2152                }
2153                if (!prefixcmp(arg, "--window=")) {
2154                        char *end;
2155                        window = strtoul(arg+9, &end, 0);
2156                        if (!arg[9] || *end)
2157                                usage(pack_usage);
2158                        continue;
2159                }
2160                if (!prefixcmp(arg, "--window-memory=")) {
2161                        if (!git_parse_ulong(arg+16, &window_memory_limit))
2162                                usage(pack_usage);
2163                        continue;
2164                }
2165                if (!prefixcmp(arg, "--threads=")) {
2166                        char *end;
2167                        delta_search_threads = strtoul(arg+10, &end, 0);
2168                        if (!arg[10] || *end || delta_search_threads < 0)
2169                                usage(pack_usage);
2170#ifndef THREADED_DELTA_SEARCH
2171                        if (delta_search_threads != 1)
2172                                warning("no threads support, "
2173                                        "ignoring %s", arg);
2174#endif
2175                        continue;
2176                }
2177                if (!prefixcmp(arg, "--depth=")) {
2178                        char *end;
2179                        depth = strtoul(arg+8, &end, 0);
2180                        if (!arg[8] || *end)
2181                                usage(pack_usage);
2182                        continue;
2183                }
2184                if (!strcmp("--progress", arg)) {
2185                        progress = 1;
2186                        continue;
2187                }
2188                if (!strcmp("--all-progress", arg)) {
2189                        progress = 2;
2190                        continue;
2191                }
2192                if (!strcmp("-q", arg)) {
2193                        progress = 0;
2194                        continue;
2195                }
2196                if (!strcmp("--no-reuse-delta", arg)) {
2197                        reuse_delta = 0;
2198                        continue;
2199                }
2200                if (!strcmp("--no-reuse-object", arg)) {
2201                        reuse_object = reuse_delta = 0;
2202                        continue;
2203                }
2204                if (!strcmp("--delta-base-offset", arg)) {
2205                        allow_ofs_delta = 1;
2206                        continue;
2207                }
2208                if (!strcmp("--stdout", arg)) {
2209                        pack_to_stdout = 1;
2210                        continue;
2211                }
2212                if (!strcmp("--revs", arg)) {
2213                        use_internal_rev_list = 1;
2214                        continue;
2215                }
2216                if (!strcmp("--keep-unreachable", arg)) {
2217                        keep_unreachable = 1;
2218                        continue;
2219                }
2220                if (!strcmp("--unpack-unreachable", arg)) {
2221                        unpack_unreachable = 1;
2222                        continue;
2223                }
2224                if (!strcmp("--include-tag", arg)) {
2225                        include_tag = 1;
2226                        continue;
2227                }
2228                if (!strcmp("--unpacked", arg) ||
2229                    !strcmp("--reflog", arg) ||
2230                    !strcmp("--all", arg)) {
2231                        use_internal_rev_list = 1;
2232                        if (rp_ac >= rp_ac_alloc - 1) {
2233                                rp_ac_alloc = alloc_nr(rp_ac_alloc);
2234                                rp_av = xrealloc(rp_av,
2235                                                 rp_ac_alloc * sizeof(*rp_av));
2236                        }
2237                        rp_av[rp_ac++] = arg;
2238                        continue;
2239                }
2240                if (!strcmp("--thin", arg)) {
2241                        use_internal_rev_list = 1;
2242                        thin = 1;
2243                        rp_av[1] = "--objects-edge";
2244                        continue;
2245                }
2246                if (!prefixcmp(arg, "--index-version=")) {
2247                        char *c;
2248                        pack_idx_default_version = strtoul(arg + 16, &c, 10);
2249                        if (pack_idx_default_version > 2)
2250                                die("bad %s", arg);
2251                        if (*c == ',')
2252                                pack_idx_off32_limit = strtoul(c+1, &c, 0);
2253                        if (*c || pack_idx_off32_limit & 0x80000000)
2254                                die("bad %s", arg);
2255                        continue;
2256                }
2257                usage(pack_usage);
2258        }
2259
2260        /* Traditionally "pack-objects [options] base extra" failed;
2261         * we would however want to take refs parameter that would
2262         * have been given to upstream rev-list ourselves, which means
2263         * we somehow want to say what the base name is.  So the
2264         * syntax would be:
2265         *
2266         * pack-objects [options] base <refs...>
2267         *
2268         * in other words, we would treat the first non-option as the
2269         * base_name and send everything else to the internal revision
2270         * walker.
2271         */
2272
2273        if (!pack_to_stdout)
2274                base_name = argv[i++];
2275
2276        if (pack_to_stdout != !base_name)
2277                usage(pack_usage);
2278
2279        if (!pack_to_stdout && !pack_size_limit)
2280                pack_size_limit = pack_size_limit_cfg;
2281
2282        if (pack_to_stdout && pack_size_limit)
2283                die("--max-pack-size cannot be used to build a pack for transfer.");
2284
2285        if (!pack_to_stdout && thin)
2286                die("--thin cannot be used to build an indexable pack.");
2287
2288        if (keep_unreachable && unpack_unreachable)
2289                die("--keep-unreachable and --unpack-unreachable are incompatible.");
2290
2291#ifdef THREADED_DELTA_SEARCH
2292        if (!delta_search_threads)      /* --threads=0 means autodetect */
2293                delta_search_threads = online_cpus();
2294#endif
2295
2296        prepare_packed_git();
2297
2298        if (progress)
2299                progress_state = start_progress("Counting objects", 0);
2300        if (!use_internal_rev_list)
2301                read_object_list_from_stdin();
2302        else {
2303                rp_av[rp_ac] = NULL;
2304                get_object_list(rp_ac, rp_av);
2305        }
2306        if (include_tag && nr_result)
2307                for_each_ref(add_ref_tag, NULL);
2308        stop_progress(&progress_state);
2309
2310        if (non_empty && !nr_result)
2311                return 0;
2312        if (nr_result)
2313                prepare_pack(window, depth);
2314        write_pack_file();
2315        if (progress)
2316                fprintf(stderr, "Total %"PRIu32" (delta %"PRIu32"),"
2317                        " reused %"PRIu32" (delta %"PRIu32")\n",
2318                        written, written_delta, reused, reused_delta);
2319        return 0;
2320}