builtin / pack-objects.con commit gitweb: Fix handling of whitespace in generated links (67976c6)
   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#ifndef NO_PTHREADS
  21#include <pthread.h>
  22#include "thread-utils.h"
  23#endif
  24
  25static const char pack_usage[] =
  26  "git pack-objects [ -q | --progress | --all-progress ]\n"
  27  "        [--all-progress-implied]\n"
  28  "        [--max-pack-size=<n>] [--local] [--incremental]\n"
  29  "        [--window=<n>] [--window-memory=<n>] [--depth=<n>]\n"
  30  "        [--no-reuse-delta] [--no-reuse-object] [--delta-base-offset]\n"
  31  "        [--threads=<n>] [--non-empty] [--revs [--unpacked | --all]]\n"
  32  "        [--reflog] [--stdout | base-name] [--include-tag]\n"
  33  "        [--keep-unreachable | --unpack-unreachable]\n"
  34  "        [< ref-list | < object-list]";
  35
  36struct object_entry {
  37        struct pack_idx_entry idx;
  38        unsigned long size;     /* uncompressed size */
  39        struct packed_git *in_pack;     /* already in pack */
  40        off_t in_pack_offset;
  41        struct object_entry *delta;     /* delta base object */
  42        struct object_entry *delta_child; /* deltified objects who bases me */
  43        struct object_entry *delta_sibling; /* other deltified objects who
  44                                             * uses the same base as me
  45                                             */
  46        void *delta_data;       /* cached delta (uncompressed) */
  47        unsigned long delta_size;       /* delta data size (uncompressed) */
  48        unsigned long z_delta_size;     /* delta data size (compressed) */
  49        unsigned int hash;      /* name hint hash */
  50        enum object_type type;
  51        enum object_type in_pack_type;  /* could be delta */
  52        unsigned char in_pack_header_size;
  53        unsigned char preferred_base; /* we do not pack this, but is available
  54                                       * to be used as the base object to delta
  55                                       * objects against.
  56                                       */
  57        unsigned char no_try_delta;
  58};
  59
  60/*
  61 * Objects we are going to pack are collected in objects array (dynamically
  62 * expanded).  nr_objects & nr_alloc controls this array.  They are stored
  63 * in the order we see -- typically rev-list --objects order that gives us
  64 * nice "minimum seek" order.
  65 */
  66static struct object_entry *objects;
  67static struct pack_idx_entry **written_list;
  68static uint32_t nr_objects, nr_alloc, nr_result, nr_written;
  69
  70static int non_empty;
  71static int reuse_delta = 1, reuse_object = 1;
  72static int keep_unreachable, unpack_unreachable, include_tag;
  73static int local;
  74static int incremental;
  75static int ignore_packed_keep;
  76static int allow_ofs_delta;
  77static const char *base_name;
  78static int progress = 1;
  79static int window = 10;
  80static unsigned long pack_size_limit, pack_size_limit_cfg;
  81static int depth = 50;
  82static int delta_search_threads;
  83static int pack_to_stdout;
  84static int num_preferred_base;
  85static struct progress *progress_state;
  86static int pack_compression_level = Z_DEFAULT_COMPRESSION;
  87static int pack_compression_seen;
  88
  89static unsigned long delta_cache_size = 0;
  90static unsigned long max_delta_cache_size = 256 * 1024 * 1024;
  91static unsigned long cache_max_small_delta_size = 1000;
  92
  93static unsigned long window_memory_limit = 0;
  94
  95/*
  96 * The object names in objects array are hashed with this hashtable,
  97 * to help looking up the entry by object name.
  98 * This hashtable is built after all the objects are seen.
  99 */
 100static int *object_ix;
 101static int object_ix_hashsz;
 102
 103/*
 104 * stats
 105 */
 106static uint32_t written, written_delta;
 107static uint32_t reused, reused_delta;
 108
 109
 110static void *get_delta(struct object_entry *entry)
 111{
 112        unsigned long size, base_size, delta_size;
 113        void *buf, *base_buf, *delta_buf;
 114        enum object_type type;
 115
 116        buf = read_sha1_file(entry->idx.sha1, &type, &size);
 117        if (!buf)
 118                die("unable to read %s", sha1_to_hex(entry->idx.sha1));
 119        base_buf = read_sha1_file(entry->delta->idx.sha1, &type, &base_size);
 120        if (!base_buf)
 121                die("unable to read %s", sha1_to_hex(entry->delta->idx.sha1));
 122        delta_buf = diff_delta(base_buf, base_size,
 123                               buf, size, &delta_size, 0);
 124        if (!delta_buf || delta_size != entry->delta_size)
 125                die("delta size changed");
 126        free(buf);
 127        free(base_buf);
 128        return delta_buf;
 129}
 130
 131static unsigned long do_compress(void **pptr, unsigned long size)
 132{
 133        z_stream stream;
 134        void *in, *out;
 135        unsigned long maxsize;
 136
 137        memset(&stream, 0, sizeof(stream));
 138        deflateInit(&stream, pack_compression_level);
 139        maxsize = deflateBound(&stream, size);
 140
 141        in = *pptr;
 142        out = xmalloc(maxsize);
 143        *pptr = out;
 144
 145        stream.next_in = in;
 146        stream.avail_in = size;
 147        stream.next_out = out;
 148        stream.avail_out = maxsize;
 149        while (deflate(&stream, Z_FINISH) == Z_OK)
 150                ; /* nothing */
 151        deflateEnd(&stream);
 152
 153        free(in);
 154        return stream.total_out;
 155}
 156
 157/*
 158 * we are going to reuse the existing object data as is.  make
 159 * sure it is not corrupt.
 160 */
 161static int check_pack_inflate(struct packed_git *p,
 162                struct pack_window **w_curs,
 163                off_t offset,
 164                off_t len,
 165                unsigned long expect)
 166{
 167        z_stream stream;
 168        unsigned char fakebuf[4096], *in;
 169        int st;
 170
 171        memset(&stream, 0, sizeof(stream));
 172        git_inflate_init(&stream);
 173        do {
 174                in = use_pack(p, w_curs, offset, &stream.avail_in);
 175                stream.next_in = in;
 176                stream.next_out = fakebuf;
 177                stream.avail_out = sizeof(fakebuf);
 178                st = git_inflate(&stream, Z_FINISH);
 179                offset += stream.next_in - in;
 180        } while (st == Z_OK || st == Z_BUF_ERROR);
 181        git_inflate_end(&stream);
 182        return (st == Z_STREAM_END &&
 183                stream.total_out == expect &&
 184                stream.total_in == len) ? 0 : -1;
 185}
 186
 187static void copy_pack_data(struct sha1file *f,
 188                struct packed_git *p,
 189                struct pack_window **w_curs,
 190                off_t offset,
 191                off_t len)
 192{
 193        unsigned char *in;
 194        unsigned int avail;
 195
 196        while (len) {
 197                in = use_pack(p, w_curs, offset, &avail);
 198                if (avail > len)
 199                        avail = (unsigned int)len;
 200                sha1write(f, in, avail);
 201                offset += avail;
 202                len -= avail;
 203        }
 204}
 205
 206static unsigned long write_object(struct sha1file *f,
 207                                  struct object_entry *entry,
 208                                  off_t write_offset)
 209{
 210        unsigned long size, limit, datalen;
 211        void *buf;
 212        unsigned char header[10], dheader[10];
 213        unsigned hdrlen;
 214        enum object_type type;
 215        int usable_delta, to_reuse;
 216
 217        if (!pack_to_stdout)
 218                crc32_begin(f);
 219
 220        type = entry->type;
 221
 222        /* apply size limit if limited packsize and not first object */
 223        if (!pack_size_limit || !nr_written)
 224                limit = 0;
 225        else if (pack_size_limit <= write_offset)
 226                /*
 227                 * the earlier object did not fit the limit; avoid
 228                 * mistaking this with unlimited (i.e. limit = 0).
 229                 */
 230                limit = 1;
 231        else
 232                limit = pack_size_limit - write_offset;
 233
 234        if (!entry->delta)
 235                usable_delta = 0;       /* no delta */
 236        else if (!pack_size_limit)
 237               usable_delta = 1;        /* unlimited packfile */
 238        else if (entry->delta->idx.offset == (off_t)-1)
 239                usable_delta = 0;       /* base was written to another pack */
 240        else if (entry->delta->idx.offset)
 241                usable_delta = 1;       /* base already exists in this pack */
 242        else
 243                usable_delta = 0;       /* base could end up in another pack */
 244
 245        if (!reuse_object)
 246                to_reuse = 0;   /* explicit */
 247        else if (!entry->in_pack)
 248                to_reuse = 0;   /* can't reuse what we don't have */
 249        else if (type == OBJ_REF_DELTA || type == OBJ_OFS_DELTA)
 250                                /* check_object() decided it for us ... */
 251                to_reuse = usable_delta;
 252                                /* ... but pack split may override that */
 253        else if (type != entry->in_pack_type)
 254                to_reuse = 0;   /* pack has delta which is unusable */
 255        else if (entry->delta)
 256                to_reuse = 0;   /* we want to pack afresh */
 257        else
 258                to_reuse = 1;   /* we have it in-pack undeltified,
 259                                 * and we do not need to deltify it.
 260                                 */
 261
 262        if (!to_reuse) {
 263                no_reuse:
 264                if (!usable_delta) {
 265                        buf = read_sha1_file(entry->idx.sha1, &type, &size);
 266                        if (!buf)
 267                                die("unable to read %s", sha1_to_hex(entry->idx.sha1));
 268                        /*
 269                         * make sure no cached delta data remains from a
 270                         * previous attempt before a pack split occurred.
 271                         */
 272                        free(entry->delta_data);
 273                        entry->delta_data = NULL;
 274                        entry->z_delta_size = 0;
 275                } else if (entry->delta_data) {
 276                        size = entry->delta_size;
 277                        buf = entry->delta_data;
 278                        entry->delta_data = NULL;
 279                        type = (allow_ofs_delta && entry->delta->idx.offset) ?
 280                                OBJ_OFS_DELTA : OBJ_REF_DELTA;
 281                } else {
 282                        buf = get_delta(entry);
 283                        size = entry->delta_size;
 284                        type = (allow_ofs_delta && entry->delta->idx.offset) ?
 285                                OBJ_OFS_DELTA : OBJ_REF_DELTA;
 286                }
 287
 288                if (entry->z_delta_size)
 289                        datalen = entry->z_delta_size;
 290                else
 291                        datalen = do_compress(&buf, size);
 292
 293                /*
 294                 * The object header is a byte of 'type' followed by zero or
 295                 * more bytes of length.
 296                 */
 297                hdrlen = encode_in_pack_object_header(type, size, header);
 298
 299                if (type == OBJ_OFS_DELTA) {
 300                        /*
 301                         * Deltas with relative base contain an additional
 302                         * encoding of the relative offset for the delta
 303                         * base from this object's position in the pack.
 304                         */
 305                        off_t ofs = entry->idx.offset - entry->delta->idx.offset;
 306                        unsigned pos = sizeof(dheader) - 1;
 307                        dheader[pos] = ofs & 127;
 308                        while (ofs >>= 7)
 309                                dheader[--pos] = 128 | (--ofs & 127);
 310                        if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit) {
 311                                free(buf);
 312                                return 0;
 313                        }
 314                        sha1write(f, header, hdrlen);
 315                        sha1write(f, dheader + pos, sizeof(dheader) - pos);
 316                        hdrlen += sizeof(dheader) - pos;
 317                } else if (type == OBJ_REF_DELTA) {
 318                        /*
 319                         * Deltas with a base reference contain
 320                         * an additional 20 bytes for the base sha1.
 321                         */
 322                        if (limit && hdrlen + 20 + datalen + 20 >= limit) {
 323                                free(buf);
 324                                return 0;
 325                        }
 326                        sha1write(f, header, hdrlen);
 327                        sha1write(f, entry->delta->idx.sha1, 20);
 328                        hdrlen += 20;
 329                } else {
 330                        if (limit && hdrlen + datalen + 20 >= limit) {
 331                                free(buf);
 332                                return 0;
 333                        }
 334                        sha1write(f, header, hdrlen);
 335                }
 336                sha1write(f, buf, datalen);
 337                free(buf);
 338        }
 339        else {
 340                struct packed_git *p = entry->in_pack;
 341                struct pack_window *w_curs = NULL;
 342                struct revindex_entry *revidx;
 343                off_t offset;
 344
 345                if (entry->delta)
 346                        type = (allow_ofs_delta && entry->delta->idx.offset) ?
 347                                OBJ_OFS_DELTA : OBJ_REF_DELTA;
 348                hdrlen = encode_in_pack_object_header(type, entry->size, header);
 349
 350                offset = entry->in_pack_offset;
 351                revidx = find_pack_revindex(p, offset);
 352                datalen = revidx[1].offset - offset;
 353                if (!pack_to_stdout && p->index_version > 1 &&
 354                    check_pack_crc(p, &w_curs, offset, datalen, revidx->nr)) {
 355                        error("bad packed object CRC for %s", sha1_to_hex(entry->idx.sha1));
 356                        unuse_pack(&w_curs);
 357                        goto no_reuse;
 358                }
 359
 360                offset += entry->in_pack_header_size;
 361                datalen -= entry->in_pack_header_size;
 362                if (!pack_to_stdout && p->index_version == 1 &&
 363                    check_pack_inflate(p, &w_curs, offset, datalen, entry->size)) {
 364                        error("corrupt packed object for %s", sha1_to_hex(entry->idx.sha1));
 365                        unuse_pack(&w_curs);
 366                        goto no_reuse;
 367                }
 368
 369                if (type == OBJ_OFS_DELTA) {
 370                        off_t ofs = entry->idx.offset - entry->delta->idx.offset;
 371                        unsigned pos = sizeof(dheader) - 1;
 372                        dheader[pos] = ofs & 127;
 373                        while (ofs >>= 7)
 374                                dheader[--pos] = 128 | (--ofs & 127);
 375                        if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit) {
 376                                unuse_pack(&w_curs);
 377                                return 0;
 378                        }
 379                        sha1write(f, header, hdrlen);
 380                        sha1write(f, dheader + pos, sizeof(dheader) - pos);
 381                        hdrlen += sizeof(dheader) - pos;
 382                        reused_delta++;
 383                } else if (type == OBJ_REF_DELTA) {
 384                        if (limit && hdrlen + 20 + datalen + 20 >= limit) {
 385                                unuse_pack(&w_curs);
 386                                return 0;
 387                        }
 388                        sha1write(f, header, hdrlen);
 389                        sha1write(f, entry->delta->idx.sha1, 20);
 390                        hdrlen += 20;
 391                        reused_delta++;
 392                } else {
 393                        if (limit && hdrlen + datalen + 20 >= limit) {
 394                                unuse_pack(&w_curs);
 395                                return 0;
 396                        }
 397                        sha1write(f, header, hdrlen);
 398                }
 399                copy_pack_data(f, p, &w_curs, offset, datalen);
 400                unuse_pack(&w_curs);
 401                reused++;
 402        }
 403        if (usable_delta)
 404                written_delta++;
 405        written++;
 406        if (!pack_to_stdout)
 407                entry->idx.crc32 = crc32_end(f);
 408        return hdrlen + datalen;
 409}
 410
 411static int write_one(struct sha1file *f,
 412                               struct object_entry *e,
 413                               off_t *offset)
 414{
 415        unsigned long size;
 416
 417        /* offset is non zero if object is written already. */
 418        if (e->idx.offset || e->preferred_base)
 419                return -1;
 420
 421        /* if we are deltified, write out base object first. */
 422        if (e->delta && !write_one(f, e->delta, offset))
 423                return 0;
 424
 425        e->idx.offset = *offset;
 426        size = write_object(f, e, *offset);
 427        if (!size) {
 428                e->idx.offset = 0;
 429                return 0;
 430        }
 431        written_list[nr_written++] = &e->idx;
 432
 433        /* make sure off_t is sufficiently large not to wrap */
 434        if (signed_add_overflows(*offset, size))
 435                die("pack too large for current definition of off_t");
 436        *offset += size;
 437        return 1;
 438}
 439
 440static void write_pack_file(void)
 441{
 442        uint32_t i = 0, j;
 443        struct sha1file *f;
 444        off_t offset;
 445        struct pack_header hdr;
 446        uint32_t nr_remaining = nr_result;
 447        time_t last_mtime = 0;
 448
 449        if (progress > pack_to_stdout)
 450                progress_state = start_progress("Writing objects", nr_result);
 451        written_list = xmalloc(nr_objects * sizeof(*written_list));
 452
 453        do {
 454                unsigned char sha1[20];
 455                char *pack_tmp_name = NULL;
 456
 457                if (pack_to_stdout) {
 458                        f = sha1fd_throughput(1, "<stdout>", progress_state);
 459                } else {
 460                        char tmpname[PATH_MAX];
 461                        int fd;
 462                        fd = odb_mkstemp(tmpname, sizeof(tmpname),
 463                                         "pack/tmp_pack_XXXXXX");
 464                        pack_tmp_name = xstrdup(tmpname);
 465                        f = sha1fd(fd, pack_tmp_name);
 466                }
 467
 468                hdr.hdr_signature = htonl(PACK_SIGNATURE);
 469                hdr.hdr_version = htonl(PACK_VERSION);
 470                hdr.hdr_entries = htonl(nr_remaining);
 471                sha1write(f, &hdr, sizeof(hdr));
 472                offset = sizeof(hdr);
 473                nr_written = 0;
 474                for (; i < nr_objects; i++) {
 475                        if (!write_one(f, objects + i, &offset))
 476                                break;
 477                        display_progress(progress_state, written);
 478                }
 479
 480                /*
 481                 * Did we write the wrong # entries in the header?
 482                 * If so, rewrite it like in fast-import
 483                 */
 484                if (pack_to_stdout) {
 485                        sha1close(f, sha1, CSUM_CLOSE);
 486                } else if (nr_written == nr_remaining) {
 487                        sha1close(f, sha1, CSUM_FSYNC);
 488                } else {
 489                        int fd = sha1close(f, sha1, 0);
 490                        fixup_pack_header_footer(fd, sha1, pack_tmp_name,
 491                                                 nr_written, sha1, offset);
 492                        close(fd);
 493                }
 494
 495                if (!pack_to_stdout) {
 496                        struct stat st;
 497                        const char *idx_tmp_name;
 498                        char tmpname[PATH_MAX];
 499
 500                        idx_tmp_name = write_idx_file(NULL, written_list,
 501                                                      nr_written, sha1);
 502
 503                        snprintf(tmpname, sizeof(tmpname), "%s-%s.pack",
 504                                 base_name, sha1_to_hex(sha1));
 505                        free_pack_by_name(tmpname);
 506                        if (adjust_shared_perm(pack_tmp_name))
 507                                die_errno("unable to make temporary pack file readable");
 508                        if (rename(pack_tmp_name, tmpname))
 509                                die_errno("unable to rename temporary pack file");
 510
 511                        /*
 512                         * Packs are runtime accessed in their mtime
 513                         * order since newer packs are more likely to contain
 514                         * younger objects.  So if we are creating multiple
 515                         * packs then we should modify the mtime of later ones
 516                         * to preserve this property.
 517                         */
 518                        if (stat(tmpname, &st) < 0) {
 519                                warning("failed to stat %s: %s",
 520                                        tmpname, strerror(errno));
 521                        } else if (!last_mtime) {
 522                                last_mtime = st.st_mtime;
 523                        } else {
 524                                struct utimbuf utb;
 525                                utb.actime = st.st_atime;
 526                                utb.modtime = --last_mtime;
 527                                if (utime(tmpname, &utb) < 0)
 528                                        warning("failed utime() on %s: %s",
 529                                                tmpname, strerror(errno));
 530                        }
 531
 532                        snprintf(tmpname, sizeof(tmpname), "%s-%s.idx",
 533                                 base_name, sha1_to_hex(sha1));
 534                        if (adjust_shared_perm(idx_tmp_name))
 535                                die_errno("unable to make temporary index file readable");
 536                        if (rename(idx_tmp_name, tmpname))
 537                                die_errno("unable to rename temporary index file");
 538
 539                        free((void *) idx_tmp_name);
 540                        free(pack_tmp_name);
 541                        puts(sha1_to_hex(sha1));
 542                }
 543
 544                /* mark written objects as written to previous pack */
 545                for (j = 0; j < nr_written; j++) {
 546                        written_list[j]->offset = (off_t)-1;
 547                }
 548                nr_remaining -= nr_written;
 549        } while (nr_remaining && i < nr_objects);
 550
 551        free(written_list);
 552        stop_progress(&progress_state);
 553        if (written != nr_result)
 554                die("wrote %"PRIu32" objects while expecting %"PRIu32,
 555                        written, nr_result);
 556}
 557
 558static int locate_object_entry_hash(const unsigned char *sha1)
 559{
 560        int i;
 561        unsigned int ui;
 562        memcpy(&ui, sha1, sizeof(unsigned int));
 563        i = ui % object_ix_hashsz;
 564        while (0 < object_ix[i]) {
 565                if (!hashcmp(sha1, objects[object_ix[i] - 1].idx.sha1))
 566                        return i;
 567                if (++i == object_ix_hashsz)
 568                        i = 0;
 569        }
 570        return -1 - i;
 571}
 572
 573static struct object_entry *locate_object_entry(const unsigned char *sha1)
 574{
 575        int i;
 576
 577        if (!object_ix_hashsz)
 578                return NULL;
 579
 580        i = locate_object_entry_hash(sha1);
 581        if (0 <= i)
 582                return &objects[object_ix[i]-1];
 583        return NULL;
 584}
 585
 586static void rehash_objects(void)
 587{
 588        uint32_t i;
 589        struct object_entry *oe;
 590
 591        object_ix_hashsz = nr_objects * 3;
 592        if (object_ix_hashsz < 1024)
 593                object_ix_hashsz = 1024;
 594        object_ix = xrealloc(object_ix, sizeof(int) * object_ix_hashsz);
 595        memset(object_ix, 0, sizeof(int) * object_ix_hashsz);
 596        for (i = 0, oe = objects; i < nr_objects; i++, oe++) {
 597                int ix = locate_object_entry_hash(oe->idx.sha1);
 598                if (0 <= ix)
 599                        continue;
 600                ix = -1 - ix;
 601                object_ix[ix] = i + 1;
 602        }
 603}
 604
 605static unsigned name_hash(const char *name)
 606{
 607        unsigned c, hash = 0;
 608
 609        if (!name)
 610                return 0;
 611
 612        /*
 613         * This effectively just creates a sortable number from the
 614         * last sixteen non-whitespace characters. Last characters
 615         * count "most", so things that end in ".c" sort together.
 616         */
 617        while ((c = *name++) != 0) {
 618                if (isspace(c))
 619                        continue;
 620                hash = (hash >> 2) + (c << 24);
 621        }
 622        return hash;
 623}
 624
 625static void setup_delta_attr_check(struct git_attr_check *check)
 626{
 627        static struct git_attr *attr_delta;
 628
 629        if (!attr_delta)
 630                attr_delta = git_attr("delta");
 631
 632        check[0].attr = attr_delta;
 633}
 634
 635static int no_try_delta(const char *path)
 636{
 637        struct git_attr_check check[1];
 638
 639        setup_delta_attr_check(check);
 640        if (git_checkattr(path, ARRAY_SIZE(check), check))
 641                return 0;
 642        if (ATTR_FALSE(check->value))
 643                return 1;
 644        return 0;
 645}
 646
 647static int add_object_entry(const unsigned char *sha1, enum object_type type,
 648                            const char *name, int exclude)
 649{
 650        struct object_entry *entry;
 651        struct packed_git *p, *found_pack = NULL;
 652        off_t found_offset = 0;
 653        int ix;
 654        unsigned hash = name_hash(name);
 655
 656        ix = nr_objects ? locate_object_entry_hash(sha1) : -1;
 657        if (ix >= 0) {
 658                if (exclude) {
 659                        entry = objects + object_ix[ix] - 1;
 660                        if (!entry->preferred_base)
 661                                nr_result--;
 662                        entry->preferred_base = 1;
 663                }
 664                return 0;
 665        }
 666
 667        if (!exclude && local && has_loose_object_nonlocal(sha1))
 668                return 0;
 669
 670        for (p = packed_git; p; p = p->next) {
 671                off_t offset = find_pack_entry_one(sha1, p);
 672                if (offset) {
 673                        if (!found_pack) {
 674                                found_offset = offset;
 675                                found_pack = p;
 676                        }
 677                        if (exclude)
 678                                break;
 679                        if (incremental)
 680                                return 0;
 681                        if (local && !p->pack_local)
 682                                return 0;
 683                        if (ignore_packed_keep && p->pack_local && p->pack_keep)
 684                                return 0;
 685                }
 686        }
 687
 688        if (nr_objects >= nr_alloc) {
 689                nr_alloc = (nr_alloc  + 1024) * 3 / 2;
 690                objects = xrealloc(objects, nr_alloc * sizeof(*entry));
 691        }
 692
 693        entry = objects + nr_objects++;
 694        memset(entry, 0, sizeof(*entry));
 695        hashcpy(entry->idx.sha1, sha1);
 696        entry->hash = hash;
 697        if (type)
 698                entry->type = type;
 699        if (exclude)
 700                entry->preferred_base = 1;
 701        else
 702                nr_result++;
 703        if (found_pack) {
 704                entry->in_pack = found_pack;
 705                entry->in_pack_offset = found_offset;
 706        }
 707
 708        if (object_ix_hashsz * 3 <= nr_objects * 4)
 709                rehash_objects();
 710        else
 711                object_ix[-1 - ix] = nr_objects;
 712
 713        display_progress(progress_state, nr_objects);
 714
 715        if (name && no_try_delta(name))
 716                entry->no_try_delta = 1;
 717
 718        return 1;
 719}
 720
 721struct pbase_tree_cache {
 722        unsigned char sha1[20];
 723        int ref;
 724        int temporary;
 725        void *tree_data;
 726        unsigned long tree_size;
 727};
 728
 729static struct pbase_tree_cache *(pbase_tree_cache[256]);
 730static int pbase_tree_cache_ix(const unsigned char *sha1)
 731{
 732        return sha1[0] % ARRAY_SIZE(pbase_tree_cache);
 733}
 734static int pbase_tree_cache_ix_incr(int ix)
 735{
 736        return (ix+1) % ARRAY_SIZE(pbase_tree_cache);
 737}
 738
 739static struct pbase_tree {
 740        struct pbase_tree *next;
 741        /* This is a phony "cache" entry; we are not
 742         * going to evict it nor find it through _get()
 743         * mechanism -- this is for the toplevel node that
 744         * would almost always change with any commit.
 745         */
 746        struct pbase_tree_cache pcache;
 747} *pbase_tree;
 748
 749static struct pbase_tree_cache *pbase_tree_get(const unsigned char *sha1)
 750{
 751        struct pbase_tree_cache *ent, *nent;
 752        void *data;
 753        unsigned long size;
 754        enum object_type type;
 755        int neigh;
 756        int my_ix = pbase_tree_cache_ix(sha1);
 757        int available_ix = -1;
 758
 759        /* pbase-tree-cache acts as a limited hashtable.
 760         * your object will be found at your index or within a few
 761         * slots after that slot if it is cached.
 762         */
 763        for (neigh = 0; neigh < 8; neigh++) {
 764                ent = pbase_tree_cache[my_ix];
 765                if (ent && !hashcmp(ent->sha1, sha1)) {
 766                        ent->ref++;
 767                        return ent;
 768                }
 769                else if (((available_ix < 0) && (!ent || !ent->ref)) ||
 770                         ((0 <= available_ix) &&
 771                          (!ent && pbase_tree_cache[available_ix])))
 772                        available_ix = my_ix;
 773                if (!ent)
 774                        break;
 775                my_ix = pbase_tree_cache_ix_incr(my_ix);
 776        }
 777
 778        /* Did not find one.  Either we got a bogus request or
 779         * we need to read and perhaps cache.
 780         */
 781        data = read_sha1_file(sha1, &type, &size);
 782        if (!data)
 783                return NULL;
 784        if (type != OBJ_TREE) {
 785                free(data);
 786                return NULL;
 787        }
 788
 789        /* We need to either cache or return a throwaway copy */
 790
 791        if (available_ix < 0)
 792                ent = NULL;
 793        else {
 794                ent = pbase_tree_cache[available_ix];
 795                my_ix = available_ix;
 796        }
 797
 798        if (!ent) {
 799                nent = xmalloc(sizeof(*nent));
 800                nent->temporary = (available_ix < 0);
 801        }
 802        else {
 803                /* evict and reuse */
 804                free(ent->tree_data);
 805                nent = ent;
 806        }
 807        hashcpy(nent->sha1, sha1);
 808        nent->tree_data = data;
 809        nent->tree_size = size;
 810        nent->ref = 1;
 811        if (!nent->temporary)
 812                pbase_tree_cache[my_ix] = nent;
 813        return nent;
 814}
 815
 816static void pbase_tree_put(struct pbase_tree_cache *cache)
 817{
 818        if (!cache->temporary) {
 819                cache->ref--;
 820                return;
 821        }
 822        free(cache->tree_data);
 823        free(cache);
 824}
 825
 826static int name_cmp_len(const char *name)
 827{
 828        int i;
 829        for (i = 0; name[i] && name[i] != '\n' && name[i] != '/'; i++)
 830                ;
 831        return i;
 832}
 833
 834static void add_pbase_object(struct tree_desc *tree,
 835                             const char *name,
 836                             int cmplen,
 837                             const char *fullname)
 838{
 839        struct name_entry entry;
 840        int cmp;
 841
 842        while (tree_entry(tree,&entry)) {
 843                if (S_ISGITLINK(entry.mode))
 844                        continue;
 845                cmp = tree_entry_len(entry.path, entry.sha1) != cmplen ? 1 :
 846                      memcmp(name, entry.path, cmplen);
 847                if (cmp > 0)
 848                        continue;
 849                if (cmp < 0)
 850                        return;
 851                if (name[cmplen] != '/') {
 852                        add_object_entry(entry.sha1,
 853                                         object_type(entry.mode),
 854                                         fullname, 1);
 855                        return;
 856                }
 857                if (S_ISDIR(entry.mode)) {
 858                        struct tree_desc sub;
 859                        struct pbase_tree_cache *tree;
 860                        const char *down = name+cmplen+1;
 861                        int downlen = name_cmp_len(down);
 862
 863                        tree = pbase_tree_get(entry.sha1);
 864                        if (!tree)
 865                                return;
 866                        init_tree_desc(&sub, tree->tree_data, tree->tree_size);
 867
 868                        add_pbase_object(&sub, down, downlen, fullname);
 869                        pbase_tree_put(tree);
 870                }
 871        }
 872}
 873
 874static unsigned *done_pbase_paths;
 875static int done_pbase_paths_num;
 876static int done_pbase_paths_alloc;
 877static int done_pbase_path_pos(unsigned hash)
 878{
 879        int lo = 0;
 880        int hi = done_pbase_paths_num;
 881        while (lo < hi) {
 882                int mi = (hi + lo) / 2;
 883                if (done_pbase_paths[mi] == hash)
 884                        return mi;
 885                if (done_pbase_paths[mi] < hash)
 886                        hi = mi;
 887                else
 888                        lo = mi + 1;
 889        }
 890        return -lo-1;
 891}
 892
 893static int check_pbase_path(unsigned hash)
 894{
 895        int pos = (!done_pbase_paths) ? -1 : done_pbase_path_pos(hash);
 896        if (0 <= pos)
 897                return 1;
 898        pos = -pos - 1;
 899        if (done_pbase_paths_alloc <= done_pbase_paths_num) {
 900                done_pbase_paths_alloc = alloc_nr(done_pbase_paths_alloc);
 901                done_pbase_paths = xrealloc(done_pbase_paths,
 902                                            done_pbase_paths_alloc *
 903                                            sizeof(unsigned));
 904        }
 905        done_pbase_paths_num++;
 906        if (pos < done_pbase_paths_num)
 907                memmove(done_pbase_paths + pos + 1,
 908                        done_pbase_paths + pos,
 909                        (done_pbase_paths_num - pos - 1) * sizeof(unsigned));
 910        done_pbase_paths[pos] = hash;
 911        return 0;
 912}
 913
 914static void add_preferred_base_object(const char *name)
 915{
 916        struct pbase_tree *it;
 917        int cmplen;
 918        unsigned hash = name_hash(name);
 919
 920        if (!num_preferred_base || check_pbase_path(hash))
 921                return;
 922
 923        cmplen = name_cmp_len(name);
 924        for (it = pbase_tree; it; it = it->next) {
 925                if (cmplen == 0) {
 926                        add_object_entry(it->pcache.sha1, OBJ_TREE, NULL, 1);
 927                }
 928                else {
 929                        struct tree_desc tree;
 930                        init_tree_desc(&tree, it->pcache.tree_data, it->pcache.tree_size);
 931                        add_pbase_object(&tree, name, cmplen, name);
 932                }
 933        }
 934}
 935
 936static void add_preferred_base(unsigned char *sha1)
 937{
 938        struct pbase_tree *it;
 939        void *data;
 940        unsigned long size;
 941        unsigned char tree_sha1[20];
 942
 943        if (window <= num_preferred_base++)
 944                return;
 945
 946        data = read_object_with_reference(sha1, tree_type, &size, tree_sha1);
 947        if (!data)
 948                return;
 949
 950        for (it = pbase_tree; it; it = it->next) {
 951                if (!hashcmp(it->pcache.sha1, tree_sha1)) {
 952                        free(data);
 953                        return;
 954                }
 955        }
 956
 957        it = xcalloc(1, sizeof(*it));
 958        it->next = pbase_tree;
 959        pbase_tree = it;
 960
 961        hashcpy(it->pcache.sha1, tree_sha1);
 962        it->pcache.tree_data = data;
 963        it->pcache.tree_size = size;
 964}
 965
 966static void cleanup_preferred_base(void)
 967{
 968        struct pbase_tree *it;
 969        unsigned i;
 970
 971        it = pbase_tree;
 972        pbase_tree = NULL;
 973        while (it) {
 974                struct pbase_tree *this = it;
 975                it = this->next;
 976                free(this->pcache.tree_data);
 977                free(this);
 978        }
 979
 980        for (i = 0; i < ARRAY_SIZE(pbase_tree_cache); i++) {
 981                if (!pbase_tree_cache[i])
 982                        continue;
 983                free(pbase_tree_cache[i]->tree_data);
 984                free(pbase_tree_cache[i]);
 985                pbase_tree_cache[i] = NULL;
 986        }
 987
 988        free(done_pbase_paths);
 989        done_pbase_paths = NULL;
 990        done_pbase_paths_num = done_pbase_paths_alloc = 0;
 991}
 992
 993static void check_object(struct object_entry *entry)
 994{
 995        if (entry->in_pack) {
 996                struct packed_git *p = entry->in_pack;
 997                struct pack_window *w_curs = NULL;
 998                const unsigned char *base_ref = NULL;
 999                struct object_entry *base_entry;
1000                unsigned long used, used_0;
1001                unsigned int avail;
1002                off_t ofs;
1003                unsigned char *buf, c;
1004
1005                buf = use_pack(p, &w_curs, entry->in_pack_offset, &avail);
1006
1007                /*
1008                 * We want in_pack_type even if we do not reuse delta
1009                 * since non-delta representations could still be reused.
1010                 */
1011                used = unpack_object_header_buffer(buf, avail,
1012                                                   &entry->in_pack_type,
1013                                                   &entry->size);
1014                if (used == 0)
1015                        goto give_up;
1016
1017                /*
1018                 * Determine if this is a delta and if so whether we can
1019                 * reuse it or not.  Otherwise let's find out as cheaply as
1020                 * possible what the actual type and size for this object is.
1021                 */
1022                switch (entry->in_pack_type) {
1023                default:
1024                        /* Not a delta hence we've already got all we need. */
1025                        entry->type = entry->in_pack_type;
1026                        entry->in_pack_header_size = used;
1027                        if (entry->type < OBJ_COMMIT || entry->type > OBJ_BLOB)
1028                                goto give_up;
1029                        unuse_pack(&w_curs);
1030                        return;
1031                case OBJ_REF_DELTA:
1032                        if (reuse_delta && !entry->preferred_base)
1033                                base_ref = use_pack(p, &w_curs,
1034                                                entry->in_pack_offset + used, NULL);
1035                        entry->in_pack_header_size = used + 20;
1036                        break;
1037                case OBJ_OFS_DELTA:
1038                        buf = use_pack(p, &w_curs,
1039                                       entry->in_pack_offset + used, NULL);
1040                        used_0 = 0;
1041                        c = buf[used_0++];
1042                        ofs = c & 127;
1043                        while (c & 128) {
1044                                ofs += 1;
1045                                if (!ofs || MSB(ofs, 7)) {
1046                                        error("delta base offset overflow in pack for %s",
1047                                              sha1_to_hex(entry->idx.sha1));
1048                                        goto give_up;
1049                                }
1050                                c = buf[used_0++];
1051                                ofs = (ofs << 7) + (c & 127);
1052                        }
1053                        ofs = entry->in_pack_offset - ofs;
1054                        if (ofs <= 0 || ofs >= entry->in_pack_offset) {
1055                                error("delta base offset out of bound for %s",
1056                                      sha1_to_hex(entry->idx.sha1));
1057                                goto give_up;
1058                        }
1059                        if (reuse_delta && !entry->preferred_base) {
1060                                struct revindex_entry *revidx;
1061                                revidx = find_pack_revindex(p, ofs);
1062                                if (!revidx)
1063                                        goto give_up;
1064                                base_ref = nth_packed_object_sha1(p, revidx->nr);
1065                        }
1066                        entry->in_pack_header_size = used + used_0;
1067                        break;
1068                }
1069
1070                if (base_ref && (base_entry = locate_object_entry(base_ref))) {
1071                        /*
1072                         * If base_ref was set above that means we wish to
1073                         * reuse delta data, and we even found that base
1074                         * in the list of objects we want to pack. Goodie!
1075                         *
1076                         * Depth value does not matter - find_deltas() will
1077                         * never consider reused delta as the base object to
1078                         * deltify other objects against, in order to avoid
1079                         * circular deltas.
1080                         */
1081                        entry->type = entry->in_pack_type;
1082                        entry->delta = base_entry;
1083                        entry->delta_size = entry->size;
1084                        entry->delta_sibling = base_entry->delta_child;
1085                        base_entry->delta_child = entry;
1086                        unuse_pack(&w_curs);
1087                        return;
1088                }
1089
1090                if (entry->type) {
1091                        /*
1092                         * This must be a delta and we already know what the
1093                         * final object type is.  Let's extract the actual
1094                         * object size from the delta header.
1095                         */
1096                        entry->size = get_size_from_delta(p, &w_curs,
1097                                        entry->in_pack_offset + entry->in_pack_header_size);
1098                        if (entry->size == 0)
1099                                goto give_up;
1100                        unuse_pack(&w_curs);
1101                        return;
1102                }
1103
1104                /*
1105                 * No choice but to fall back to the recursive delta walk
1106                 * with sha1_object_info() to find about the object type
1107                 * at this point...
1108                 */
1109                give_up:
1110                unuse_pack(&w_curs);
1111        }
1112
1113        entry->type = sha1_object_info(entry->idx.sha1, &entry->size);
1114        /*
1115         * The error condition is checked in prepare_pack().  This is
1116         * to permit a missing preferred base object to be ignored
1117         * as a preferred base.  Doing so can result in a larger
1118         * pack file, but the transfer will still take place.
1119         */
1120}
1121
1122static int pack_offset_sort(const void *_a, const void *_b)
1123{
1124        const struct object_entry *a = *(struct object_entry **)_a;
1125        const struct object_entry *b = *(struct object_entry **)_b;
1126
1127        /* avoid filesystem trashing with loose objects */
1128        if (!a->in_pack && !b->in_pack)
1129                return hashcmp(a->idx.sha1, b->idx.sha1);
1130
1131        if (a->in_pack < b->in_pack)
1132                return -1;
1133        if (a->in_pack > b->in_pack)
1134                return 1;
1135        return a->in_pack_offset < b->in_pack_offset ? -1 :
1136                        (a->in_pack_offset > b->in_pack_offset);
1137}
1138
1139static void get_object_details(void)
1140{
1141        uint32_t i;
1142        struct object_entry **sorted_by_offset;
1143
1144        sorted_by_offset = xcalloc(nr_objects, sizeof(struct object_entry *));
1145        for (i = 0; i < nr_objects; i++)
1146                sorted_by_offset[i] = objects + i;
1147        qsort(sorted_by_offset, nr_objects, sizeof(*sorted_by_offset), pack_offset_sort);
1148
1149        for (i = 0; i < nr_objects; i++)
1150                check_object(sorted_by_offset[i]);
1151
1152        free(sorted_by_offset);
1153}
1154
1155/*
1156 * We search for deltas in a list sorted by type, by filename hash, and then
1157 * by size, so that we see progressively smaller and smaller files.
1158 * That's because we prefer deltas to be from the bigger file
1159 * to the smaller -- deletes are potentially cheaper, but perhaps
1160 * more importantly, the bigger file is likely the more recent
1161 * one.  The deepest deltas are therefore the oldest objects which are
1162 * less susceptible to be accessed often.
1163 */
1164static int type_size_sort(const void *_a, const void *_b)
1165{
1166        const struct object_entry *a = *(struct object_entry **)_a;
1167        const struct object_entry *b = *(struct object_entry **)_b;
1168
1169        if (a->type > b->type)
1170                return -1;
1171        if (a->type < b->type)
1172                return 1;
1173        if (a->hash > b->hash)
1174                return -1;
1175        if (a->hash < b->hash)
1176                return 1;
1177        if (a->preferred_base > b->preferred_base)
1178                return -1;
1179        if (a->preferred_base < b->preferred_base)
1180                return 1;
1181        if (a->size > b->size)
1182                return -1;
1183        if (a->size < b->size)
1184                return 1;
1185        return a < b ? -1 : (a > b);  /* newest first */
1186}
1187
1188struct unpacked {
1189        struct object_entry *entry;
1190        void *data;
1191        struct delta_index *index;
1192        unsigned depth;
1193};
1194
1195static int delta_cacheable(unsigned long src_size, unsigned long trg_size,
1196                           unsigned long delta_size)
1197{
1198        if (max_delta_cache_size && delta_cache_size + delta_size > max_delta_cache_size)
1199                return 0;
1200
1201        if (delta_size < cache_max_small_delta_size)
1202                return 1;
1203
1204        /* cache delta, if objects are large enough compared to delta size */
1205        if ((src_size >> 20) + (trg_size >> 21) > (delta_size >> 10))
1206                return 1;
1207
1208        return 0;
1209}
1210
1211#ifndef NO_PTHREADS
1212
1213static pthread_mutex_t read_mutex;
1214#define read_lock()             pthread_mutex_lock(&read_mutex)
1215#define read_unlock()           pthread_mutex_unlock(&read_mutex)
1216
1217static pthread_mutex_t cache_mutex;
1218#define cache_lock()            pthread_mutex_lock(&cache_mutex)
1219#define cache_unlock()          pthread_mutex_unlock(&cache_mutex)
1220
1221static pthread_mutex_t progress_mutex;
1222#define progress_lock()         pthread_mutex_lock(&progress_mutex)
1223#define progress_unlock()       pthread_mutex_unlock(&progress_mutex)
1224
1225#else
1226
1227#define read_lock()             (void)0
1228#define read_unlock()           (void)0
1229#define cache_lock()            (void)0
1230#define cache_unlock()          (void)0
1231#define progress_lock()         (void)0
1232#define progress_unlock()       (void)0
1233
1234#endif
1235
1236static int try_delta(struct unpacked *trg, struct unpacked *src,
1237                     unsigned max_depth, unsigned long *mem_usage)
1238{
1239        struct object_entry *trg_entry = trg->entry;
1240        struct object_entry *src_entry = src->entry;
1241        unsigned long trg_size, src_size, delta_size, sizediff, max_size, sz;
1242        unsigned ref_depth;
1243        enum object_type type;
1244        void *delta_buf;
1245
1246        /* Don't bother doing diffs between different types */
1247        if (trg_entry->type != src_entry->type)
1248                return -1;
1249
1250        /*
1251         * We do not bother to try a delta that we discarded
1252         * on an earlier try, but only when reusing delta data.
1253         */
1254        if (reuse_delta && trg_entry->in_pack &&
1255            trg_entry->in_pack == src_entry->in_pack &&
1256            trg_entry->in_pack_type != OBJ_REF_DELTA &&
1257            trg_entry->in_pack_type != OBJ_OFS_DELTA)
1258                return 0;
1259
1260        /* Let's not bust the allowed depth. */
1261        if (src->depth >= max_depth)
1262                return 0;
1263
1264        /* Now some size filtering heuristics. */
1265        trg_size = trg_entry->size;
1266        if (!trg_entry->delta) {
1267                max_size = trg_size/2 - 20;
1268                ref_depth = 1;
1269        } else {
1270                max_size = trg_entry->delta_size;
1271                ref_depth = trg->depth;
1272        }
1273        max_size = (uint64_t)max_size * (max_depth - src->depth) /
1274                                                (max_depth - ref_depth + 1);
1275        if (max_size == 0)
1276                return 0;
1277        src_size = src_entry->size;
1278        sizediff = src_size < trg_size ? trg_size - src_size : 0;
1279        if (sizediff >= max_size)
1280                return 0;
1281        if (trg_size < src_size / 32)
1282                return 0;
1283
1284        /* Load data if not already done */
1285        if (!trg->data) {
1286                read_lock();
1287                trg->data = read_sha1_file(trg_entry->idx.sha1, &type, &sz);
1288                read_unlock();
1289                if (!trg->data)
1290                        die("object %s cannot be read",
1291                            sha1_to_hex(trg_entry->idx.sha1));
1292                if (sz != trg_size)
1293                        die("object %s inconsistent object length (%lu vs %lu)",
1294                            sha1_to_hex(trg_entry->idx.sha1), sz, trg_size);
1295                *mem_usage += sz;
1296        }
1297        if (!src->data) {
1298                read_lock();
1299                src->data = read_sha1_file(src_entry->idx.sha1, &type, &sz);
1300                read_unlock();
1301                if (!src->data) {
1302                        if (src_entry->preferred_base) {
1303                                static int warned = 0;
1304                                if (!warned++)
1305                                        warning("object %s cannot be read",
1306                                                sha1_to_hex(src_entry->idx.sha1));
1307                                /*
1308                                 * Those objects are not included in the
1309                                 * resulting pack.  Be resilient and ignore
1310                                 * them if they can't be read, in case the
1311                                 * pack could be created nevertheless.
1312                                 */
1313                                return 0;
1314                        }
1315                        die("object %s cannot be read",
1316                            sha1_to_hex(src_entry->idx.sha1));
1317                }
1318                if (sz != src_size)
1319                        die("object %s inconsistent object length (%lu vs %lu)",
1320                            sha1_to_hex(src_entry->idx.sha1), sz, src_size);
1321                *mem_usage += sz;
1322        }
1323        if (!src->index) {
1324                src->index = create_delta_index(src->data, src_size);
1325                if (!src->index) {
1326                        static int warned = 0;
1327                        if (!warned++)
1328                                warning("suboptimal pack - out of memory");
1329                        return 0;
1330                }
1331                *mem_usage += sizeof_delta_index(src->index);
1332        }
1333
1334        delta_buf = create_delta(src->index, trg->data, trg_size, &delta_size, max_size);
1335        if (!delta_buf)
1336                return 0;
1337
1338        if (trg_entry->delta) {
1339                /* Prefer only shallower same-sized deltas. */
1340                if (delta_size == trg_entry->delta_size &&
1341                    src->depth + 1 >= trg->depth) {
1342                        free(delta_buf);
1343                        return 0;
1344                }
1345        }
1346
1347        /*
1348         * Handle memory allocation outside of the cache
1349         * accounting lock.  Compiler will optimize the strangeness
1350         * away when NO_PTHREADS is defined.
1351         */
1352        free(trg_entry->delta_data);
1353        cache_lock();
1354        if (trg_entry->delta_data) {
1355                delta_cache_size -= trg_entry->delta_size;
1356                trg_entry->delta_data = NULL;
1357        }
1358        if (delta_cacheable(src_size, trg_size, delta_size)) {
1359                delta_cache_size += delta_size;
1360                cache_unlock();
1361                trg_entry->delta_data = xrealloc(delta_buf, delta_size);
1362        } else {
1363                cache_unlock();
1364                free(delta_buf);
1365        }
1366
1367        trg_entry->delta = src_entry;
1368        trg_entry->delta_size = delta_size;
1369        trg->depth = src->depth + 1;
1370
1371        return 1;
1372}
1373
1374static unsigned int check_delta_limit(struct object_entry *me, unsigned int n)
1375{
1376        struct object_entry *child = me->delta_child;
1377        unsigned int m = n;
1378        while (child) {
1379                unsigned int c = check_delta_limit(child, n + 1);
1380                if (m < c)
1381                        m = c;
1382                child = child->delta_sibling;
1383        }
1384        return m;
1385}
1386
1387static unsigned long free_unpacked(struct unpacked *n)
1388{
1389        unsigned long freed_mem = sizeof_delta_index(n->index);
1390        free_delta_index(n->index);
1391        n->index = NULL;
1392        if (n->data) {
1393                freed_mem += n->entry->size;
1394                free(n->data);
1395                n->data = NULL;
1396        }
1397        n->entry = NULL;
1398        n->depth = 0;
1399        return freed_mem;
1400}
1401
1402static void find_deltas(struct object_entry **list, unsigned *list_size,
1403                        int window, int depth, unsigned *processed)
1404{
1405        uint32_t i, idx = 0, count = 0;
1406        struct unpacked *array;
1407        unsigned long mem_usage = 0;
1408
1409        array = xcalloc(window, sizeof(struct unpacked));
1410
1411        for (;;) {
1412                struct object_entry *entry;
1413                struct unpacked *n = array + idx;
1414                int j, max_depth, best_base = -1;
1415
1416                progress_lock();
1417                if (!*list_size) {
1418                        progress_unlock();
1419                        break;
1420                }
1421                entry = *list++;
1422                (*list_size)--;
1423                if (!entry->preferred_base) {
1424                        (*processed)++;
1425                        display_progress(progress_state, *processed);
1426                }
1427                progress_unlock();
1428
1429                mem_usage -= free_unpacked(n);
1430                n->entry = entry;
1431
1432                while (window_memory_limit &&
1433                       mem_usage > window_memory_limit &&
1434                       count > 1) {
1435                        uint32_t tail = (idx + window - count) % window;
1436                        mem_usage -= free_unpacked(array + tail);
1437                        count--;
1438                }
1439
1440                /* We do not compute delta to *create* objects we are not
1441                 * going to pack.
1442                 */
1443                if (entry->preferred_base)
1444                        goto next;
1445
1446                /*
1447                 * If the current object is at pack edge, take the depth the
1448                 * objects that depend on the current object into account
1449                 * otherwise they would become too deep.
1450                 */
1451                max_depth = depth;
1452                if (entry->delta_child) {
1453                        max_depth -= check_delta_limit(entry, 0);
1454                        if (max_depth <= 0)
1455                                goto next;
1456                }
1457
1458                j = window;
1459                while (--j > 0) {
1460                        int ret;
1461                        uint32_t other_idx = idx + j;
1462                        struct unpacked *m;
1463                        if (other_idx >= window)
1464                                other_idx -= window;
1465                        m = array + other_idx;
1466                        if (!m->entry)
1467                                break;
1468                        ret = try_delta(n, m, max_depth, &mem_usage);
1469                        if (ret < 0)
1470                                break;
1471                        else if (ret > 0)
1472                                best_base = other_idx;
1473                }
1474
1475                /*
1476                 * If we decided to cache the delta data, then it is best
1477                 * to compress it right away.  First because we have to do
1478                 * it anyway, and doing it here while we're threaded will
1479                 * save a lot of time in the non threaded write phase,
1480                 * as well as allow for caching more deltas within
1481                 * the same cache size limit.
1482                 * ...
1483                 * But only if not writing to stdout, since in that case
1484                 * the network is most likely throttling writes anyway,
1485                 * and therefore it is best to go to the write phase ASAP
1486                 * instead, as we can afford spending more time compressing
1487                 * between writes at that moment.
1488                 */
1489                if (entry->delta_data && !pack_to_stdout) {
1490                        entry->z_delta_size = do_compress(&entry->delta_data,
1491                                                          entry->delta_size);
1492                        cache_lock();
1493                        delta_cache_size -= entry->delta_size;
1494                        delta_cache_size += entry->z_delta_size;
1495                        cache_unlock();
1496                }
1497
1498                /* if we made n a delta, and if n is already at max
1499                 * depth, leaving it in the window is pointless.  we
1500                 * should evict it first.
1501                 */
1502                if (entry->delta && max_depth <= n->depth)
1503                        continue;
1504
1505                /*
1506                 * Move the best delta base up in the window, after the
1507                 * currently deltified object, to keep it longer.  It will
1508                 * be the first base object to be attempted next.
1509                 */
1510                if (entry->delta) {
1511                        struct unpacked swap = array[best_base];
1512                        int dist = (window + idx - best_base) % window;
1513                        int dst = best_base;
1514                        while (dist--) {
1515                                int src = (dst + 1) % window;
1516                                array[dst] = array[src];
1517                                dst = src;
1518                        }
1519                        array[dst] = swap;
1520                }
1521
1522                next:
1523                idx++;
1524                if (count + 1 < window)
1525                        count++;
1526                if (idx >= window)
1527                        idx = 0;
1528        }
1529
1530        for (i = 0; i < window; ++i) {
1531                free_delta_index(array[i].index);
1532                free(array[i].data);
1533        }
1534        free(array);
1535}
1536
1537#ifndef NO_PTHREADS
1538
1539static void try_to_free_from_threads(size_t size)
1540{
1541        read_lock();
1542        release_pack_memory(size, -1);
1543        read_unlock();
1544}
1545
1546try_to_free_t old_try_to_free_routine;
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;
1572
1573/*
1574 * Mutex and conditional variable can't be statically-initialized on Windows.
1575 */
1576static void init_threaded_search(void)
1577{
1578        init_recursive_mutex(&read_mutex);
1579        pthread_mutex_init(&cache_mutex, NULL);
1580        pthread_mutex_init(&progress_mutex, NULL);
1581        pthread_cond_init(&progress_cond, NULL);
1582        old_try_to_free_routine = set_try_to_free_routine(try_to_free_from_threads);
1583}
1584
1585static void cleanup_threaded_search(void)
1586{
1587        set_try_to_free_routine(old_try_to_free_routine);
1588        pthread_cond_destroy(&progress_cond);
1589        pthread_mutex_destroy(&read_mutex);
1590        pthread_mutex_destroy(&cache_mutex);
1591        pthread_mutex_destroy(&progress_mutex);
1592}
1593
1594static void *threaded_find_deltas(void *arg)
1595{
1596        struct thread_params *me = arg;
1597
1598        while (me->remaining) {
1599                find_deltas(me->list, &me->remaining,
1600                            me->window, me->depth, me->processed);
1601
1602                progress_lock();
1603                me->working = 0;
1604                pthread_cond_signal(&progress_cond);
1605                progress_unlock();
1606
1607                /*
1608                 * We must not set ->data_ready before we wait on the
1609                 * condition because the main thread may have set it to 1
1610                 * before we get here. In order to be sure that new
1611                 * work is available if we see 1 in ->data_ready, it
1612                 * was initialized to 0 before this thread was spawned
1613                 * and we reset it to 0 right away.
1614                 */
1615                pthread_mutex_lock(&me->mutex);
1616                while (!me->data_ready)
1617                        pthread_cond_wait(&me->cond, &me->mutex);
1618                me->data_ready = 0;
1619                pthread_mutex_unlock(&me->mutex);
1620        }
1621        /* leave ->working 1 so that this doesn't get more work assigned */
1622        return NULL;
1623}
1624
1625static void ll_find_deltas(struct object_entry **list, unsigned list_size,
1626                           int window, int depth, unsigned *processed)
1627{
1628        struct thread_params *p;
1629        int i, ret, active_threads = 0;
1630
1631        init_threaded_search();
1632
1633        if (!delta_search_threads)      /* --threads=0 means autodetect */
1634                delta_search_threads = online_cpus();
1635        if (delta_search_threads <= 1) {
1636                find_deltas(list, &list_size, window, depth, processed);
1637                cleanup_threaded_search();
1638                return;
1639        }
1640        if (progress > pack_to_stdout)
1641                fprintf(stderr, "Delta compression using up to %d threads.\n",
1642                                delta_search_threads);
1643        p = xcalloc(delta_search_threads, sizeof(*p));
1644
1645        /* Partition the work amongst work threads. */
1646        for (i = 0; i < delta_search_threads; i++) {
1647                unsigned sub_size = list_size / (delta_search_threads - i);
1648
1649                /* don't use too small segments or no deltas will be found */
1650                if (sub_size < 2*window && i+1 < delta_search_threads)
1651                        sub_size = 0;
1652
1653                p[i].window = window;
1654                p[i].depth = depth;
1655                p[i].processed = processed;
1656                p[i].working = 1;
1657                p[i].data_ready = 0;
1658
1659                /* try to split chunks on "path" boundaries */
1660                while (sub_size && sub_size < list_size &&
1661                       list[sub_size]->hash &&
1662                       list[sub_size]->hash == list[sub_size-1]->hash)
1663                        sub_size++;
1664
1665                p[i].list = list;
1666                p[i].list_size = sub_size;
1667                p[i].remaining = sub_size;
1668
1669                list += sub_size;
1670                list_size -= sub_size;
1671        }
1672
1673        /* Start work threads. */
1674        for (i = 0; i < delta_search_threads; i++) {
1675                if (!p[i].list_size)
1676                        continue;
1677                pthread_mutex_init(&p[i].mutex, NULL);
1678                pthread_cond_init(&p[i].cond, NULL);
1679                ret = pthread_create(&p[i].thread, NULL,
1680                                     threaded_find_deltas, &p[i]);
1681                if (ret)
1682                        die("unable to create thread: %s", strerror(ret));
1683                active_threads++;
1684        }
1685
1686        /*
1687         * Now let's wait for work completion.  Each time a thread is done
1688         * with its work, we steal half of the remaining work from the
1689         * thread with the largest number of unprocessed objects and give
1690         * it to that newly idle thread.  This ensure good load balancing
1691         * until the remaining object list segments are simply too short
1692         * to be worth splitting anymore.
1693         */
1694        while (active_threads) {
1695                struct thread_params *target = NULL;
1696                struct thread_params *victim = NULL;
1697                unsigned sub_size = 0;
1698
1699                progress_lock();
1700                for (;;) {
1701                        for (i = 0; !target && i < delta_search_threads; i++)
1702                                if (!p[i].working)
1703                                        target = &p[i];
1704                        if (target)
1705                                break;
1706                        pthread_cond_wait(&progress_cond, &progress_mutex);
1707                }
1708
1709                for (i = 0; i < delta_search_threads; i++)
1710                        if (p[i].remaining > 2*window &&
1711                            (!victim || victim->remaining < p[i].remaining))
1712                                victim = &p[i];
1713                if (victim) {
1714                        sub_size = victim->remaining / 2;
1715                        list = victim->list + victim->list_size - sub_size;
1716                        while (sub_size && list[0]->hash &&
1717                               list[0]->hash == list[-1]->hash) {
1718                                list++;
1719                                sub_size--;
1720                        }
1721                        if (!sub_size) {
1722                                /*
1723                                 * It is possible for some "paths" to have
1724                                 * so many objects that no hash boundary
1725                                 * might be found.  Let's just steal the
1726                                 * exact half in that case.
1727                                 */
1728                                sub_size = victim->remaining / 2;
1729                                list -= sub_size;
1730                        }
1731                        target->list = list;
1732                        victim->list_size -= sub_size;
1733                        victim->remaining -= sub_size;
1734                }
1735                target->list_size = sub_size;
1736                target->remaining = sub_size;
1737                target->working = 1;
1738                progress_unlock();
1739
1740                pthread_mutex_lock(&target->mutex);
1741                target->data_ready = 1;
1742                pthread_cond_signal(&target->cond);
1743                pthread_mutex_unlock(&target->mutex);
1744
1745                if (!sub_size) {
1746                        pthread_join(target->thread, NULL);
1747                        pthread_cond_destroy(&target->cond);
1748                        pthread_mutex_destroy(&target->mutex);
1749                        active_threads--;
1750                }
1751        }
1752        cleanup_threaded_search();
1753        free(p);
1754}
1755
1756#else
1757#define ll_find_deltas(l, s, w, d, p)   find_deltas(l, &s, w, d, p)
1758#endif
1759
1760static int add_ref_tag(const char *path, const unsigned char *sha1, int flag, void *cb_data)
1761{
1762        unsigned char peeled[20];
1763
1764        if (!prefixcmp(path, "refs/tags/") && /* is a tag? */
1765            !peel_ref(path, peeled)        && /* peelable? */
1766            !is_null_sha1(peeled)          && /* annotated tag? */
1767            locate_object_entry(peeled))      /* object packed? */
1768                add_object_entry(sha1, OBJ_TAG, NULL, 0);
1769        return 0;
1770}
1771
1772static void prepare_pack(int window, int depth)
1773{
1774        struct object_entry **delta_list;
1775        uint32_t i, nr_deltas;
1776        unsigned n;
1777
1778        get_object_details();
1779
1780        /*
1781         * If we're locally repacking then we need to be doubly careful
1782         * from now on in order to make sure no stealth corruption gets
1783         * propagated to the new pack.  Clients receiving streamed packs
1784         * should validate everything they get anyway so no need to incur
1785         * the additional cost here in that case.
1786         */
1787        if (!pack_to_stdout)
1788                do_check_packed_object_crc = 1;
1789
1790        if (!nr_objects || !window || !depth)
1791                return;
1792
1793        delta_list = xmalloc(nr_objects * sizeof(*delta_list));
1794        nr_deltas = n = 0;
1795
1796        for (i = 0; i < nr_objects; i++) {
1797                struct object_entry *entry = objects + i;
1798
1799                if (entry->delta)
1800                        /* This happens if we decided to reuse existing
1801                         * delta from a pack.  "reuse_delta &&" is implied.
1802                         */
1803                        continue;
1804
1805                if (entry->size < 50)
1806                        continue;
1807
1808                if (entry->no_try_delta)
1809                        continue;
1810
1811                if (!entry->preferred_base) {
1812                        nr_deltas++;
1813                        if (entry->type < 0)
1814                                die("unable to get type of object %s",
1815                                    sha1_to_hex(entry->idx.sha1));
1816                } else {
1817                        if (entry->type < 0) {
1818                                /*
1819                                 * This object is not found, but we
1820                                 * don't have to include it anyway.
1821                                 */
1822                                continue;
1823                        }
1824                }
1825
1826                delta_list[n++] = entry;
1827        }
1828
1829        if (nr_deltas && n > 1) {
1830                unsigned nr_done = 0;
1831                if (progress)
1832                        progress_state = start_progress("Compressing objects",
1833                                                        nr_deltas);
1834                qsort(delta_list, n, sizeof(*delta_list), type_size_sort);
1835                ll_find_deltas(delta_list, n, window+1, depth, &nr_done);
1836                stop_progress(&progress_state);
1837                if (nr_done != nr_deltas)
1838                        die("inconsistency with delta count");
1839        }
1840        free(delta_list);
1841}
1842
1843static int git_pack_config(const char *k, const char *v, void *cb)
1844{
1845        if (!strcmp(k, "pack.window")) {
1846                window = git_config_int(k, v);
1847                return 0;
1848        }
1849        if (!strcmp(k, "pack.windowmemory")) {
1850                window_memory_limit = git_config_ulong(k, v);
1851                return 0;
1852        }
1853        if (!strcmp(k, "pack.depth")) {
1854                depth = git_config_int(k, v);
1855                return 0;
1856        }
1857        if (!strcmp(k, "pack.compression")) {
1858                int level = git_config_int(k, v);
1859                if (level == -1)
1860                        level = Z_DEFAULT_COMPRESSION;
1861                else if (level < 0 || level > Z_BEST_COMPRESSION)
1862                        die("bad pack compression level %d", level);
1863                pack_compression_level = level;
1864                pack_compression_seen = 1;
1865                return 0;
1866        }
1867        if (!strcmp(k, "pack.deltacachesize")) {
1868                max_delta_cache_size = git_config_int(k, v);
1869                return 0;
1870        }
1871        if (!strcmp(k, "pack.deltacachelimit")) {
1872                cache_max_small_delta_size = git_config_int(k, v);
1873                return 0;
1874        }
1875        if (!strcmp(k, "pack.threads")) {
1876                delta_search_threads = git_config_int(k, v);
1877                if (delta_search_threads < 0)
1878                        die("invalid number of threads specified (%d)",
1879                            delta_search_threads);
1880#ifdef NO_PTHREADS
1881                if (delta_search_threads != 1)
1882                        warning("no threads support, ignoring %s", k);
1883#endif
1884                return 0;
1885        }
1886        if (!strcmp(k, "pack.indexversion")) {
1887                pack_idx_default_version = git_config_int(k, v);
1888                if (pack_idx_default_version > 2)
1889                        die("bad pack.indexversion=%"PRIu32,
1890                                pack_idx_default_version);
1891                return 0;
1892        }
1893        if (!strcmp(k, "pack.packsizelimit")) {
1894                pack_size_limit_cfg = git_config_ulong(k, v);
1895                return 0;
1896        }
1897        return git_default_config(k, v, cb);
1898}
1899
1900static void read_object_list_from_stdin(void)
1901{
1902        char line[40 + 1 + PATH_MAX + 2];
1903        unsigned char sha1[20];
1904
1905        for (;;) {
1906                if (!fgets(line, sizeof(line), stdin)) {
1907                        if (feof(stdin))
1908                                break;
1909                        if (!ferror(stdin))
1910                                die("fgets returned NULL, not EOF, not error!");
1911                        if (errno != EINTR)
1912                                die_errno("fgets");
1913                        clearerr(stdin);
1914                        continue;
1915                }
1916                if (line[0] == '-') {
1917                        if (get_sha1_hex(line+1, sha1))
1918                                die("expected edge sha1, got garbage:\n %s",
1919                                    line);
1920                        add_preferred_base(sha1);
1921                        continue;
1922                }
1923                if (get_sha1_hex(line, sha1))
1924                        die("expected sha1, got garbage:\n %s", line);
1925
1926                add_preferred_base_object(line+41);
1927                add_object_entry(sha1, 0, line+41, 0);
1928        }
1929}
1930
1931#define OBJECT_ADDED (1u<<20)
1932
1933static void show_commit(struct commit *commit, void *data)
1934{
1935        add_object_entry(commit->object.sha1, OBJ_COMMIT, NULL, 0);
1936        commit->object.flags |= OBJECT_ADDED;
1937}
1938
1939static void show_object(struct object *obj, const struct name_path *path, const char *last)
1940{
1941        char *name = path_name(path, last);
1942
1943        add_preferred_base_object(name);
1944        add_object_entry(obj->sha1, obj->type, name, 0);
1945        obj->flags |= OBJECT_ADDED;
1946
1947        /*
1948         * We will have generated the hash from the name,
1949         * but not saved a pointer to it - we can free it
1950         */
1951        free((char *)name);
1952}
1953
1954static void show_edge(struct commit *commit)
1955{
1956        add_preferred_base(commit->object.sha1);
1957}
1958
1959struct in_pack_object {
1960        off_t offset;
1961        struct object *object;
1962};
1963
1964struct in_pack {
1965        int alloc;
1966        int nr;
1967        struct in_pack_object *array;
1968};
1969
1970static void mark_in_pack_object(struct object *object, struct packed_git *p, struct in_pack *in_pack)
1971{
1972        in_pack->array[in_pack->nr].offset = find_pack_entry_one(object->sha1, p);
1973        in_pack->array[in_pack->nr].object = object;
1974        in_pack->nr++;
1975}
1976
1977/*
1978 * Compare the objects in the offset order, in order to emulate the
1979 * "git rev-list --objects" output that produced the pack originally.
1980 */
1981static int ofscmp(const void *a_, const void *b_)
1982{
1983        struct in_pack_object *a = (struct in_pack_object *)a_;
1984        struct in_pack_object *b = (struct in_pack_object *)b_;
1985
1986        if (a->offset < b->offset)
1987                return -1;
1988        else if (a->offset > b->offset)
1989                return 1;
1990        else
1991                return hashcmp(a->object->sha1, b->object->sha1);
1992}
1993
1994static void add_objects_in_unpacked_packs(struct rev_info *revs)
1995{
1996        struct packed_git *p;
1997        struct in_pack in_pack;
1998        uint32_t i;
1999
2000        memset(&in_pack, 0, sizeof(in_pack));
2001
2002        for (p = packed_git; p; p = p->next) {
2003                const unsigned char *sha1;
2004                struct object *o;
2005
2006                if (!p->pack_local || p->pack_keep)
2007                        continue;
2008                if (open_pack_index(p))
2009                        die("cannot open pack index");
2010
2011                ALLOC_GROW(in_pack.array,
2012                           in_pack.nr + p->num_objects,
2013                           in_pack.alloc);
2014
2015                for (i = 0; i < p->num_objects; i++) {
2016                        sha1 = nth_packed_object_sha1(p, i);
2017                        o = lookup_unknown_object(sha1);
2018                        if (!(o->flags & OBJECT_ADDED))
2019                                mark_in_pack_object(o, p, &in_pack);
2020                        o->flags |= OBJECT_ADDED;
2021                }
2022        }
2023
2024        if (in_pack.nr) {
2025                qsort(in_pack.array, in_pack.nr, sizeof(in_pack.array[0]),
2026                      ofscmp);
2027                for (i = 0; i < in_pack.nr; i++) {
2028                        struct object *o = in_pack.array[i].object;
2029                        add_object_entry(o->sha1, o->type, "", 0);
2030                }
2031        }
2032        free(in_pack.array);
2033}
2034
2035static int has_sha1_pack_kept_or_nonlocal(const unsigned char *sha1)
2036{
2037        static struct packed_git *last_found = (void *)1;
2038        struct packed_git *p;
2039
2040        p = (last_found != (void *)1) ? last_found : packed_git;
2041
2042        while (p) {
2043                if ((!p->pack_local || p->pack_keep) &&
2044                        find_pack_entry_one(sha1, p)) {
2045                        last_found = p;
2046                        return 1;
2047                }
2048                if (p == last_found)
2049                        p = packed_git;
2050                else
2051                        p = p->next;
2052                if (p == last_found)
2053                        p = p->next;
2054        }
2055        return 0;
2056}
2057
2058static void loosen_unused_packed_objects(struct rev_info *revs)
2059{
2060        struct packed_git *p;
2061        uint32_t i;
2062        const unsigned char *sha1;
2063
2064        for (p = packed_git; p; p = p->next) {
2065                if (!p->pack_local || p->pack_keep)
2066                        continue;
2067
2068                if (open_pack_index(p))
2069                        die("cannot open pack index");
2070
2071                for (i = 0; i < p->num_objects; i++) {
2072                        sha1 = nth_packed_object_sha1(p, i);
2073                        if (!locate_object_entry(sha1) &&
2074                                !has_sha1_pack_kept_or_nonlocal(sha1))
2075                                if (force_object_loose(sha1, p->mtime))
2076                                        die("unable to force loose object");
2077                }
2078        }
2079}
2080
2081static void get_object_list(int ac, const char **av)
2082{
2083        struct rev_info revs;
2084        char line[1000];
2085        int flags = 0;
2086
2087        init_revisions(&revs, NULL);
2088        save_commit_buffer = 0;
2089        setup_revisions(ac, av, &revs, NULL);
2090
2091        while (fgets(line, sizeof(line), stdin) != NULL) {
2092                int len = strlen(line);
2093                if (len && line[len - 1] == '\n')
2094                        line[--len] = 0;
2095                if (!len)
2096                        break;
2097                if (*line == '-') {
2098                        if (!strcmp(line, "--not")) {
2099                                flags ^= UNINTERESTING;
2100                                continue;
2101                        }
2102                        die("not a rev '%s'", line);
2103                }
2104                if (handle_revision_arg(line, &revs, flags, 1))
2105                        die("bad revision '%s'", line);
2106        }
2107
2108        if (prepare_revision_walk(&revs))
2109                die("revision walk setup failed");
2110        mark_edges_uninteresting(revs.commits, &revs, show_edge);
2111        traverse_commit_list(&revs, show_commit, show_object, NULL);
2112
2113        if (keep_unreachable)
2114                add_objects_in_unpacked_packs(&revs);
2115        if (unpack_unreachable)
2116                loosen_unused_packed_objects(&revs);
2117}
2118
2119int cmd_pack_objects(int argc, const char **argv, const char *prefix)
2120{
2121        int use_internal_rev_list = 0;
2122        int thin = 0;
2123        int all_progress_implied = 0;
2124        uint32_t i;
2125        const char **rp_av;
2126        int rp_ac_alloc = 64;
2127        int rp_ac;
2128
2129        read_replace_refs = 0;
2130
2131        rp_av = xcalloc(rp_ac_alloc, sizeof(*rp_av));
2132
2133        rp_av[0] = "pack-objects";
2134        rp_av[1] = "--objects"; /* --thin will make it --objects-edge */
2135        rp_ac = 2;
2136
2137        git_config(git_pack_config, NULL);
2138        if (!pack_compression_seen && core_compression_seen)
2139                pack_compression_level = core_compression_level;
2140
2141        progress = isatty(2);
2142        for (i = 1; i < argc; i++) {
2143                const char *arg = argv[i];
2144
2145                if (*arg != '-')
2146                        break;
2147
2148                if (!strcmp("--non-empty", arg)) {
2149                        non_empty = 1;
2150                        continue;
2151                }
2152                if (!strcmp("--local", arg)) {
2153                        local = 1;
2154                        continue;
2155                }
2156                if (!strcmp("--incremental", arg)) {
2157                        incremental = 1;
2158                        continue;
2159                }
2160                if (!strcmp("--honor-pack-keep", arg)) {
2161                        ignore_packed_keep = 1;
2162                        continue;
2163                }
2164                if (!prefixcmp(arg, "--compression=")) {
2165                        char *end;
2166                        int level = strtoul(arg+14, &end, 0);
2167                        if (!arg[14] || *end)
2168                                usage(pack_usage);
2169                        if (level == -1)
2170                                level = Z_DEFAULT_COMPRESSION;
2171                        else if (level < 0 || level > Z_BEST_COMPRESSION)
2172                                die("bad pack compression level %d", level);
2173                        pack_compression_level = level;
2174                        continue;
2175                }
2176                if (!prefixcmp(arg, "--max-pack-size=")) {
2177                        pack_size_limit_cfg = 0;
2178                        if (!git_parse_ulong(arg+16, &pack_size_limit))
2179                                usage(pack_usage);
2180                        continue;
2181                }
2182                if (!prefixcmp(arg, "--window=")) {
2183                        char *end;
2184                        window = strtoul(arg+9, &end, 0);
2185                        if (!arg[9] || *end)
2186                                usage(pack_usage);
2187                        continue;
2188                }
2189                if (!prefixcmp(arg, "--window-memory=")) {
2190                        if (!git_parse_ulong(arg+16, &window_memory_limit))
2191                                usage(pack_usage);
2192                        continue;
2193                }
2194                if (!prefixcmp(arg, "--threads=")) {
2195                        char *end;
2196                        delta_search_threads = strtoul(arg+10, &end, 0);
2197                        if (!arg[10] || *end || delta_search_threads < 0)
2198                                usage(pack_usage);
2199#ifdef NO_PTHREADS
2200                        if (delta_search_threads != 1)
2201                                warning("no threads support, "
2202                                        "ignoring %s", arg);
2203#endif
2204                        continue;
2205                }
2206                if (!prefixcmp(arg, "--depth=")) {
2207                        char *end;
2208                        depth = strtoul(arg+8, &end, 0);
2209                        if (!arg[8] || *end)
2210                                usage(pack_usage);
2211                        continue;
2212                }
2213                if (!strcmp("--progress", arg)) {
2214                        progress = 1;
2215                        continue;
2216                }
2217                if (!strcmp("--all-progress", arg)) {
2218                        progress = 2;
2219                        continue;
2220                }
2221                if (!strcmp("--all-progress-implied", arg)) {
2222                        all_progress_implied = 1;
2223                        continue;
2224                }
2225                if (!strcmp("-q", arg)) {
2226                        progress = 0;
2227                        continue;
2228                }
2229                if (!strcmp("--no-reuse-delta", arg)) {
2230                        reuse_delta = 0;
2231                        continue;
2232                }
2233                if (!strcmp("--no-reuse-object", arg)) {
2234                        reuse_object = reuse_delta = 0;
2235                        continue;
2236                }
2237                if (!strcmp("--delta-base-offset", arg)) {
2238                        allow_ofs_delta = 1;
2239                        continue;
2240                }
2241                if (!strcmp("--stdout", arg)) {
2242                        pack_to_stdout = 1;
2243                        continue;
2244                }
2245                if (!strcmp("--revs", arg)) {
2246                        use_internal_rev_list = 1;
2247                        continue;
2248                }
2249                if (!strcmp("--keep-unreachable", arg)) {
2250                        keep_unreachable = 1;
2251                        continue;
2252                }
2253                if (!strcmp("--unpack-unreachable", arg)) {
2254                        unpack_unreachable = 1;
2255                        continue;
2256                }
2257                if (!strcmp("--include-tag", arg)) {
2258                        include_tag = 1;
2259                        continue;
2260                }
2261                if (!strcmp("--unpacked", arg) ||
2262                    !strcmp("--reflog", arg) ||
2263                    !strcmp("--all", arg)) {
2264                        use_internal_rev_list = 1;
2265                        if (rp_ac >= rp_ac_alloc - 1) {
2266                                rp_ac_alloc = alloc_nr(rp_ac_alloc);
2267                                rp_av = xrealloc(rp_av,
2268                                                 rp_ac_alloc * sizeof(*rp_av));
2269                        }
2270                        rp_av[rp_ac++] = arg;
2271                        continue;
2272                }
2273                if (!strcmp("--thin", arg)) {
2274                        use_internal_rev_list = 1;
2275                        thin = 1;
2276                        rp_av[1] = "--objects-edge";
2277                        continue;
2278                }
2279                if (!prefixcmp(arg, "--index-version=")) {
2280                        char *c;
2281                        pack_idx_default_version = strtoul(arg + 16, &c, 10);
2282                        if (pack_idx_default_version > 2)
2283                                die("bad %s", arg);
2284                        if (*c == ',')
2285                                pack_idx_off32_limit = strtoul(c+1, &c, 0);
2286                        if (*c || pack_idx_off32_limit & 0x80000000)
2287                                die("bad %s", arg);
2288                        continue;
2289                }
2290                if (!strcmp(arg, "--keep-true-parents")) {
2291                        grafts_replace_parents = 0;
2292                        continue;
2293                }
2294                usage(pack_usage);
2295        }
2296
2297        /* Traditionally "pack-objects [options] base extra" failed;
2298         * we would however want to take refs parameter that would
2299         * have been given to upstream rev-list ourselves, which means
2300         * we somehow want to say what the base name is.  So the
2301         * syntax would be:
2302         *
2303         * pack-objects [options] base <refs...>
2304         *
2305         * in other words, we would treat the first non-option as the
2306         * base_name and send everything else to the internal revision
2307         * walker.
2308         */
2309
2310        if (!pack_to_stdout)
2311                base_name = argv[i++];
2312
2313        if (pack_to_stdout != !base_name)
2314                usage(pack_usage);
2315
2316        if (!pack_to_stdout && !pack_size_limit)
2317                pack_size_limit = pack_size_limit_cfg;
2318        if (pack_to_stdout && pack_size_limit)
2319                die("--max-pack-size cannot be used to build a pack for transfer.");
2320        if (pack_size_limit && pack_size_limit < 1024*1024) {
2321                warning("minimum pack size limit is 1 MiB");
2322                pack_size_limit = 1024*1024;
2323        }
2324
2325        if (!pack_to_stdout && thin)
2326                die("--thin cannot be used to build an indexable pack.");
2327
2328        if (keep_unreachable && unpack_unreachable)
2329                die("--keep-unreachable and --unpack-unreachable are incompatible.");
2330
2331        if (progress && all_progress_implied)
2332                progress = 2;
2333
2334        prepare_packed_git();
2335
2336        if (progress)
2337                progress_state = start_progress("Counting objects", 0);
2338        if (!use_internal_rev_list)
2339                read_object_list_from_stdin();
2340        else {
2341                rp_av[rp_ac] = NULL;
2342                get_object_list(rp_ac, rp_av);
2343        }
2344        cleanup_preferred_base();
2345        if (include_tag && nr_result)
2346                for_each_ref(add_ref_tag, NULL);
2347        stop_progress(&progress_state);
2348
2349        if (non_empty && !nr_result)
2350                return 0;
2351        if (nr_result)
2352                prepare_pack(window, depth);
2353        write_pack_file();
2354        if (progress)
2355                fprintf(stderr, "Total %"PRIu32" (delta %"PRIu32"),"
2356                        " reused %"PRIu32" (delta %"PRIu32")\n",
2357                        written, written_delta, reused, reused_delta);
2358        return 0;
2359}