git.oblomov.eu Git - git/blob - builtin/pack-objects.c

   1 #include "builtin.h"
   2 #include "cache.h"
   3 #include "repository.h"
   4 #include "config.h"
   5 #include "attr.h"
   6 #include "object.h"
   7 #include "blob.h"
   8 #include "commit.h"
   9 #include "tag.h"
  10 #include "tree.h"
  11 #include "delta.h"
  12 #include "pack.h"
  13 #include "pack-revindex.h"
  14 #include "csum-file.h"
  15 #include "tree-walk.h"
  16 #include "diff.h"
  17 #include "revision.h"
  18 #include "list-objects.h"
  19 #include "list-objects-filter.h"
  20 #include "list-objects-filter-options.h"
  21 #include "pack-objects.h"
  22 #include "progress.h"
  23 #include "refs.h"
  24 #include "streaming.h"
  25 #include "thread-utils.h"
  26 #include "pack-bitmap.h"
  27 #include "reachable.h"
  28 #include "sha1-array.h"
  29 #include "argv-array.h"
  30 #include "list.h"
  31 #include "packfile.h"
  32 #include "object-store.h"
  33 #include "dir.h"
  34
  35 #define IN_PACK(obj) oe_in_pack(&to_pack, obj)
  36 #define SIZE(obj) oe_size(&to_pack, obj)
  37 #define SET_SIZE(obj,size) oe_set_size(&to_pack, obj, size)
  38 #define DELTA_SIZE(obj) oe_delta_size(&to_pack, obj)
  39 #define DELTA(obj) oe_delta(&to_pack, obj)
  40 #define DELTA_CHILD(obj) oe_delta_child(&to_pack, obj)
  41 #define DELTA_SIBLING(obj) oe_delta_sibling(&to_pack, obj)
  42 #define SET_DELTA(obj, val) oe_set_delta(&to_pack, obj, val)
  43 #define SET_DELTA_SIZE(obj, val) oe_set_delta_size(&to_pack, obj, val)
  44 #define SET_DELTA_CHILD(obj, val) oe_set_delta_child(&to_pack, obj, val)
  45 #define SET_DELTA_SIBLING(obj, val) oe_set_delta_sibling(&to_pack, obj, val)
  46
  47 static const char *pack_usage[] = {
  48         N_("git pack-objects --stdout [<options>...] [< <ref-list> | < <object-list>]"),
  49         N_("git pack-objects [<options>...] <base-name> [< <ref-list> | < <object-list>]"),
  50         NULL
  51 };
  52
  53 /*
  54  * Objects we are going to pack are collected in the `to_pack` structure.
  55  * It contains an array (dynamically expanded) of the object data, and a map
  56  * that can resolve SHA1s to their position in the array.
  57  */
  58 static struct packing_data to_pack;
  59
  60 static struct pack_idx_entry **written_list;
  61 static uint32_t nr_result, nr_written, nr_seen;
  62
  63 static int non_empty;
  64 static int reuse_delta = 1, reuse_object = 1;
  65 static int keep_unreachable, unpack_unreachable, include_tag;
  66 static timestamp_t unpack_unreachable_expiration;
  67 static int pack_loose_unreachable;
  68 static int local;
  69 static int have_non_local_packs;
  70 static int incremental;
  71 static int ignore_packed_keep_on_disk;
  72 static int ignore_packed_keep_in_core;
  73 static int allow_ofs_delta;
  74 static struct pack_idx_option pack_idx_opts;
  75 static const char *base_name;
  76 static int progress = 1;
  77 static int window = 10;
  78 static unsigned long pack_size_limit;
  79 static int depth = 50;
  80 static int delta_search_threads;
  81 static int pack_to_stdout;
  82 static int num_preferred_base;
  83 static struct progress *progress_state;
  84
  85 static struct packed_git *reuse_packfile;
  86 static uint32_t reuse_packfile_objects;
  87 static off_t reuse_packfile_offset;
  88
  89 static int use_bitmap_index_default = 1;
  90 static int use_bitmap_index = -1;
  91 static int write_bitmap_index;
  92 static uint16_t write_bitmap_options;
  93
  94 static int exclude_promisor_objects;
  95
  96 static unsigned long delta_cache_size = 0;
  97 static unsigned long max_delta_cache_size = DEFAULT_DELTA_CACHE_SIZE;
  98 static unsigned long cache_max_small_delta_size = 1000;
  99
 100 static unsigned long window_memory_limit = 0;
 101
 102 static struct list_objects_filter_options filter_options;
 103
 104 enum missing_action {
 105         MA_ERROR = 0,      /* fail if any missing objects are encountered */
 106         MA_ALLOW_ANY,      /* silently allow ALL missing objects */
 107         MA_ALLOW_PROMISOR, /* silently allow all missing PROMISOR objects */
 108 };
 109 static enum missing_action arg_missing_action;
 110 static show_object_fn fn_show_object;
 111
 112 /*
 113  * stats
 114  */
 115 static uint32_t written, written_delta;
 116 static uint32_t reused, reused_delta;
 117
 118 /*
 119  * Indexed commits
 120  */
 121 static struct commit **indexed_commits;
 122 static unsigned int indexed_commits_nr;
 123 static unsigned int indexed_commits_alloc;
 124
 125 static void index_commit_for_bitmap(struct commit *commit)
 126 {
 127         if (indexed_commits_nr >= indexed_commits_alloc) {
 128                 indexed_commits_alloc = (indexed_commits_alloc + 32) * 2;
 129                 REALLOC_ARRAY(indexed_commits, indexed_commits_alloc);
 130         }
 131
 132         indexed_commits[indexed_commits_nr++] = commit;
 133 }
 134
 135 static void *get_delta(struct object_entry *entry)
 136 {
 137         unsigned long size, base_size, delta_size;
 138         void *buf, *base_buf, *delta_buf;
 139         enum object_type type;
 140
 141         buf = read_object_file(&entry->idx.oid, &type, &size);
 142         if (!buf)
 143                 die("unable to read %s", oid_to_hex(&entry->idx.oid));
 144         base_buf = read_object_file(&DELTA(entry)->idx.oid, &type,
 145                                     &base_size);
 146         if (!base_buf)
 147                 die("unable to read %s",
 148                     oid_to_hex(&DELTA(entry)->idx.oid));
 149         delta_buf = diff_delta(base_buf, base_size,
 150                                buf, size, &delta_size, 0);
 151         if (!delta_buf || delta_size != DELTA_SIZE(entry))
 152                 die("delta size changed");
 153         free(buf);
 154         free(base_buf);
 155         return delta_buf;
 156 }
 157
 158 static unsigned long do_compress(void **pptr, unsigned long size)
 159 {
 160         git_zstream stream;
 161         void *in, *out;
 162         unsigned long maxsize;
 163
 164         git_deflate_init(&stream, pack_compression_level);
 165         maxsize = git_deflate_bound(&stream, size);
 166
 167         in = *pptr;
 168         out = xmalloc(maxsize);
 169         *pptr = out;
 170
 171         stream.next_in = in;
 172         stream.avail_in = size;
 173         stream.next_out = out;
 174         stream.avail_out = maxsize;
 175         while (git_deflate(&stream, Z_FINISH) == Z_OK)
 176                 ; /* nothing */
 177         git_deflate_end(&stream);
 178
 179         free(in);
 180         return stream.total_out;
 181 }
 182
 183 static unsigned long write_large_blob_data(struct git_istream *st, struct hashfile *f,
 184                                            const struct object_id *oid)
 185 {
 186         git_zstream stream;
 187         unsigned char ibuf[1024 * 16];
 188         unsigned char obuf[1024 * 16];
 189         unsigned long olen = 0;
 190
 191         git_deflate_init(&stream, pack_compression_level);
 192
 193         for (;;) {
 194                 ssize_t readlen;
 195                 int zret = Z_OK;
 196                 readlen = read_istream(st, ibuf, sizeof(ibuf));
 197                 if (readlen == -1)
 198                         die(_("unable to read %s"), oid_to_hex(oid));
 199
 200                 stream.next_in = ibuf;
 201                 stream.avail_in = readlen;
 202                 while ((stream.avail_in || readlen == 0) &&
 203                        (zret == Z_OK || zret == Z_BUF_ERROR)) {
 204                         stream.next_out = obuf;
 205                         stream.avail_out = sizeof(obuf);
 206                         zret = git_deflate(&stream, readlen ? 0 : Z_FINISH);
 207                         hashwrite(f, obuf, stream.next_out - obuf);
 208                         olen += stream.next_out - obuf;
 209                 }
 210                 if (stream.avail_in)
 211                         die(_("deflate error (%d)"), zret);
 212                 if (readlen == 0) {
 213                         if (zret != Z_STREAM_END)
 214                                 die(_("deflate error (%d)"), zret);
 215                         break;
 216                 }
 217         }
 218         git_deflate_end(&stream);
 219         return olen;
 220 }
 221
 222 /*
 223  * we are going to reuse the existing object data as is.  make
 224  * sure it is not corrupt.
 225  */
 226 static int check_pack_inflate(struct packed_git *p,
 227                 struct pack_window **w_curs,
 228                 off_t offset,
 229                 off_t len,
 230                 unsigned long expect)
 231 {
 232         git_zstream stream;
 233         unsigned char fakebuf[4096], *in;
 234         int st;
 235
 236         memset(&stream, 0, sizeof(stream));
 237         git_inflate_init(&stream);
 238         do {
 239                 in = use_pack(p, w_curs, offset, &stream.avail_in);
 240                 stream.next_in = in;
 241                 stream.next_out = fakebuf;
 242                 stream.avail_out = sizeof(fakebuf);
 243                 st = git_inflate(&stream, Z_FINISH);
 244                 offset += stream.next_in - in;
 245         } while (st == Z_OK || st == Z_BUF_ERROR);
 246         git_inflate_end(&stream);
 247         return (st == Z_STREAM_END &&
 248                 stream.total_out == expect &&
 249                 stream.total_in == len) ? 0 : -1;
 250 }
 251
 252 static void copy_pack_data(struct hashfile *f,
 253                 struct packed_git *p,
 254                 struct pack_window **w_curs,
 255                 off_t offset,
 256                 off_t len)
 257 {
 258         unsigned char *in;
 259         unsigned long avail;
 260
 261         while (len) {
 262                 in = use_pack(p, w_curs, offset, &avail);
 263                 if (avail > len)
 264                         avail = (unsigned long)len;
 265                 hashwrite(f, in, avail);
 266                 offset += avail;
 267                 len -= avail;
 268         }
 269 }
 270
 271 /* Return 0 if we will bust the pack-size limit */
 272 static unsigned long write_no_reuse_object(struct hashfile *f, struct object_entry *entry,
 273                                            unsigned long limit, int usable_delta)
 274 {
 275         unsigned long size, datalen;
 276         unsigned char header[MAX_PACK_OBJECT_HEADER],
 277                       dheader[MAX_PACK_OBJECT_HEADER];
 278         unsigned hdrlen;
 279         enum object_type type;
 280         void *buf;
 281         struct git_istream *st = NULL;
 282         const unsigned hashsz = the_hash_algo->rawsz;
 283
 284         if (!usable_delta) {
 285                 if (oe_type(entry) == OBJ_BLOB &&
 286                     oe_size_greater_than(&to_pack, entry, big_file_threshold) &&
 287                     (st = open_istream(&entry->idx.oid, &type, &size, NULL)) != NULL)
 288                         buf = NULL;
 289                 else {
 290                         buf = read_object_file(&entry->idx.oid, &type, &size);
 291                         if (!buf)
 292                                 die(_("unable to read %s"),
 293                                     oid_to_hex(&entry->idx.oid));
 294                 }
 295                 /*
 296                  * make sure no cached delta data remains from a
 297                  * previous attempt before a pack split occurred.
 298                  */
 299                 FREE_AND_NULL(entry->delta_data);
 300                 entry->z_delta_size = 0;
 301         } else if (entry->delta_data) {
 302                 size = DELTA_SIZE(entry);
 303                 buf = entry->delta_data;
 304                 entry->delta_data = NULL;
 305                 type = (allow_ofs_delta && DELTA(entry)->idx.offset) ?
 306                         OBJ_OFS_DELTA : OBJ_REF_DELTA;
 307         } else {
 308                 buf = get_delta(entry);
 309                 size = DELTA_SIZE(entry);
 310                 type = (allow_ofs_delta && DELTA(entry)->idx.offset) ?
 311                         OBJ_OFS_DELTA : OBJ_REF_DELTA;
 312         }
 313
 314         if (st) /* large blob case, just assume we don't compress well */
 315                 datalen = size;
 316         else if (entry->z_delta_size)
 317                 datalen = entry->z_delta_size;
 318         else
 319                 datalen = do_compress(&buf, size);
 320
 321         /*
 322          * The object header is a byte of 'type' followed by zero or
 323          * more bytes of length.
 324          */
 325         hdrlen = encode_in_pack_object_header(header, sizeof(header),
 326                                               type, size);
 327
 328         if (type == OBJ_OFS_DELTA) {
 329                 /*
 330                  * Deltas with relative base contain an additional
 331                  * encoding of the relative offset for the delta
 332                  * base from this object's position in the pack.
 333                  */
 334                 off_t ofs = entry->idx.offset - DELTA(entry)->idx.offset;
 335                 unsigned pos = sizeof(dheader) - 1;
 336                 dheader[pos] = ofs & 127;
 337                 while (ofs >>= 7)
 338                         dheader[--pos] = 128 | (--ofs & 127);
 339                 if (limit && hdrlen + sizeof(dheader) - pos + datalen + hashsz >= limit) {
 340                         if (st)
 341                                 close_istream(st);
 342                         free(buf);
 343                         return 0;
 344                 }
 345                 hashwrite(f, header, hdrlen);
 346                 hashwrite(f, dheader + pos, sizeof(dheader) - pos);
 347                 hdrlen += sizeof(dheader) - pos;
 348         } else if (type == OBJ_REF_DELTA) {
 349                 /*
 350                  * Deltas with a base reference contain
 351                  * additional bytes for the base object ID.
 352                  */
 353                 if (limit && hdrlen + hashsz + datalen + hashsz >= limit) {
 354                         if (st)
 355                                 close_istream(st);
 356                         free(buf);
 357                         return 0;
 358                 }
 359                 hashwrite(f, header, hdrlen);
 360                 hashwrite(f, DELTA(entry)->idx.oid.hash, hashsz);
 361                 hdrlen += hashsz;
 362         } else {
 363                 if (limit && hdrlen + datalen + hashsz >= limit) {
 364                         if (st)
 365                                 close_istream(st);
 366                         free(buf);
 367                         return 0;
 368                 }
 369                 hashwrite(f, header, hdrlen);
 370         }
 371         if (st) {
 372                 datalen = write_large_blob_data(st, f, &entry->idx.oid);
 373                 close_istream(st);
 374         } else {
 375                 hashwrite(f, buf, datalen);
 376                 free(buf);
 377         }
 378
 379         return hdrlen + datalen;
 380 }
 381
 382 /* Return 0 if we will bust the pack-size limit */
 383 static off_t write_reuse_object(struct hashfile *f, struct object_entry *entry,
 384                                 unsigned long limit, int usable_delta)
 385 {
 386         struct packed_git *p = IN_PACK(entry);
 387         struct pack_window *w_curs = NULL;
 388         struct revindex_entry *revidx;
 389         off_t offset;
 390         enum object_type type = oe_type(entry);
 391         off_t datalen;
 392         unsigned char header[MAX_PACK_OBJECT_HEADER],
 393                       dheader[MAX_PACK_OBJECT_HEADER];
 394         unsigned hdrlen;
 395         const unsigned hashsz = the_hash_algo->rawsz;
 396         unsigned long entry_size = SIZE(entry);
 397
 398         if (DELTA(entry))
 399                 type = (allow_ofs_delta && DELTA(entry)->idx.offset) ?
 400                         OBJ_OFS_DELTA : OBJ_REF_DELTA;
 401         hdrlen = encode_in_pack_object_header(header, sizeof(header),
 402                                               type, entry_size);
 403
 404         offset = entry->in_pack_offset;
 405         revidx = find_pack_revindex(p, offset);
 406         datalen = revidx[1].offset - offset;
 407         if (!pack_to_stdout && p->index_version > 1 &&
 408             check_pack_crc(p, &w_curs, offset, datalen, revidx->nr)) {
 409                 error("bad packed object CRC for %s",
 410                       oid_to_hex(&entry->idx.oid));
 411                 unuse_pack(&w_curs);
 412                 return write_no_reuse_object(f, entry, limit, usable_delta);
 413         }
 414
 415         offset += entry->in_pack_header_size;
 416         datalen -= entry->in_pack_header_size;
 417
 418         if (!pack_to_stdout && p->index_version == 1 &&
 419             check_pack_inflate(p, &w_curs, offset, datalen, entry_size)) {
 420                 error("corrupt packed object for %s",
 421                       oid_to_hex(&entry->idx.oid));
 422                 unuse_pack(&w_curs);
 423                 return write_no_reuse_object(f, entry, limit, usable_delta);
 424         }
 425
 426         if (type == OBJ_OFS_DELTA) {
 427                 off_t ofs = entry->idx.offset - DELTA(entry)->idx.offset;
 428                 unsigned pos = sizeof(dheader) - 1;
 429                 dheader[pos] = ofs & 127;
 430                 while (ofs >>= 7)
 431                         dheader[--pos] = 128 | (--ofs & 127);
 432                 if (limit && hdrlen + sizeof(dheader) - pos + datalen + hashsz >= limit) {
 433                         unuse_pack(&w_curs);
 434                         return 0;
 435                 }
 436                 hashwrite(f, header, hdrlen);
 437                 hashwrite(f, dheader + pos, sizeof(dheader) - pos);
 438                 hdrlen += sizeof(dheader) - pos;
 439                 reused_delta++;
 440         } else if (type == OBJ_REF_DELTA) {
 441                 if (limit && hdrlen + hashsz + datalen + hashsz >= limit) {
 442                         unuse_pack(&w_curs);
 443                         return 0;
 444                 }
 445                 hashwrite(f, header, hdrlen);
 446                 hashwrite(f, DELTA(entry)->idx.oid.hash, hashsz);
 447                 hdrlen += hashsz;
 448                 reused_delta++;
 449         } else {
 450                 if (limit && hdrlen + datalen + hashsz >= limit) {
 451                         unuse_pack(&w_curs);
 452                         return 0;
 453                 }
 454                 hashwrite(f, header, hdrlen);
 455         }
 456         copy_pack_data(f, p, &w_curs, offset, datalen);
 457         unuse_pack(&w_curs);
 458         reused++;
 459         return hdrlen + datalen;
 460 }
 461
 462 /* Return 0 if we will bust the pack-size limit */
 463 static off_t write_object(struct hashfile *f,
 464                           struct object_entry *entry,
 465                           off_t write_offset)
 466 {
 467         unsigned long limit;
 468         off_t len;
 469         int usable_delta, to_reuse;
 470
 471         if (!pack_to_stdout)
 472                 crc32_begin(f);
 473
 474         /* apply size limit if limited packsize and not first object */
 475         if (!pack_size_limit || !nr_written)
 476                 limit = 0;
 477         else if (pack_size_limit <= write_offset)
 478                 /*
 479                  * the earlier object did not fit the limit; avoid
 480                  * mistaking this with unlimited (i.e. limit = 0).
 481                  */
 482                 limit = 1;
 483         else
 484                 limit = pack_size_limit - write_offset;
 485
 486         if (!DELTA(entry))
 487                 usable_delta = 0;       /* no delta */
 488         else if (!pack_size_limit)
 489                usable_delta = 1;        /* unlimited packfile */
 490         else if (DELTA(entry)->idx.offset == (off_t)-1)
 491                 usable_delta = 0;       /* base was written to another pack */
 492         else if (DELTA(entry)->idx.offset)
 493                 usable_delta = 1;       /* base already exists in this pack */
 494         else
 495                 usable_delta = 0;       /* base could end up in another pack */
 496
 497         if (!reuse_object)
 498                 to_reuse = 0;   /* explicit */
 499         else if (!IN_PACK(entry))
 500                 to_reuse = 0;   /* can't reuse what we don't have */
 501         else if (oe_type(entry) == OBJ_REF_DELTA ||
 502                  oe_type(entry) == OBJ_OFS_DELTA)
 503                                 /* check_object() decided it for us ... */
 504                 to_reuse = usable_delta;
 505                                 /* ... but pack split may override that */
 506         else if (oe_type(entry) != entry->in_pack_type)
 507                 to_reuse = 0;   /* pack has delta which is unusable */
 508         else if (DELTA(entry))
 509                 to_reuse = 0;   /* we want to pack afresh */
 510         else
 511                 to_reuse = 1;   /* we have it in-pack undeltified,
 512                                  * and we do not need to deltify it.
 513                                  */
 514
 515         if (!to_reuse)
 516                 len = write_no_reuse_object(f, entry, limit, usable_delta);
 517         else
 518                 len = write_reuse_object(f, entry, limit, usable_delta);
 519         if (!len)
 520                 return 0;
 521
 522         if (usable_delta)
 523                 written_delta++;
 524         written++;
 525         if (!pack_to_stdout)
 526                 entry->idx.crc32 = crc32_end(f);
 527         return len;
 528 }
 529
 530 enum write_one_status {
 531         WRITE_ONE_SKIP = -1, /* already written */
 532         WRITE_ONE_BREAK = 0, /* writing this will bust the limit; not written */
 533         WRITE_ONE_WRITTEN = 1, /* normal */
 534         WRITE_ONE_RECURSIVE = 2 /* already scheduled to be written */
 535 };
 536
 537 static enum write_one_status write_one(struct hashfile *f,
 538                                        struct object_entry *e,
 539                                        off_t *offset)
 540 {
 541         off_t size;
 542         int recursing;
 543
 544         /*
 545          * we set offset to 1 (which is an impossible value) to mark
 546          * the fact that this object is involved in "write its base
 547          * first before writing a deltified object" recursion.
 548          */
 549         recursing = (e->idx.offset == 1);
 550         if (recursing) {
 551                 warning("recursive delta detected for object %s",
 552                         oid_to_hex(&e->idx.oid));
 553                 return WRITE_ONE_RECURSIVE;
 554         } else if (e->idx.offset || e->preferred_base) {
 555                 /* offset is non zero if object is written already. */
 556                 return WRITE_ONE_SKIP;
 557         }
 558
 559         /* if we are deltified, write out base object first. */
 560         if (DELTA(e)) {
 561                 e->idx.offset = 1; /* now recurse */
 562                 switch (write_one(f, DELTA(e), offset)) {
 563                 case WRITE_ONE_RECURSIVE:
 564                         /* we cannot depend on this one */
 565                         SET_DELTA(e, NULL);
 566                         break;
 567                 default:
 568                         break;
 569                 case WRITE_ONE_BREAK:
 570                         e->idx.offset = recursing;
 571                         return WRITE_ONE_BREAK;
 572                 }
 573         }
 574
 575         e->idx.offset = *offset;
 576         size = write_object(f, e, *offset);
 577         if (!size) {
 578                 e->idx.offset = recursing;
 579                 return WRITE_ONE_BREAK;
 580         }
 581         written_list[nr_written++] = &e->idx;
 582
 583         /* make sure off_t is sufficiently large not to wrap */
 584         if (signed_add_overflows(*offset, size))
 585                 die("pack too large for current definition of off_t");
 586         *offset += size;
 587         return WRITE_ONE_WRITTEN;
 588 }
 589
 590 static int mark_tagged(const char *path, const struct object_id *oid, int flag,
 591                        void *cb_data)
 592 {
 593         struct object_id peeled;
 594         struct object_entry *entry = packlist_find(&to_pack, oid->hash, NULL);
 595
 596         if (entry)
 597                 entry->tagged = 1;
 598         if (!peel_ref(path, &peeled)) {
 599                 entry = packlist_find(&to_pack, peeled.hash, NULL);
 600                 if (entry)
 601                         entry->tagged = 1;
 602         }
 603         return 0;
 604 }
 605
 606 static inline void add_to_write_order(struct object_entry **wo,
 607                                unsigned int *endp,
 608                                struct object_entry *e)
 609 {
 610         if (e->filled)
 611                 return;
 612         wo[(*endp)++] = e;
 613         e->filled = 1;
 614 }
 615
 616 static void add_descendants_to_write_order(struct object_entry **wo,
 617                                            unsigned int *endp,
 618                                            struct object_entry *e)
 619 {
 620         int add_to_order = 1;
 621         while (e) {
 622                 if (add_to_order) {
 623                         struct object_entry *s;
 624                         /* add this node... */
 625                         add_to_write_order(wo, endp, e);
 626                         /* all its siblings... */
 627                         for (s = DELTA_SIBLING(e); s; s = DELTA_SIBLING(s)) {
 628                                 add_to_write_order(wo, endp, s);
 629                         }
 630                 }
 631                 /* drop down a level to add left subtree nodes if possible */
 632                 if (DELTA_CHILD(e)) {
 633                         add_to_order = 1;
 634                         e = DELTA_CHILD(e);
 635                 } else {
 636                         add_to_order = 0;
 637                         /* our sibling might have some children, it is next */
 638                         if (DELTA_SIBLING(e)) {
 639                                 e = DELTA_SIBLING(e);
 640                                 continue;
 641                         }
 642                         /* go back to our parent node */
 643                         e = DELTA(e);
 644                         while (e && !DELTA_SIBLING(e)) {
 645                                 /* we're on the right side of a subtree, keep
 646                                  * going up until we can go right again */
 647                                 e = DELTA(e);
 648                         }
 649                         if (!e) {
 650                                 /* done- we hit our original root node */
 651                                 return;
 652                         }
 653                         /* pass it off to sibling at this level */
 654                         e = DELTA_SIBLING(e);
 655                 }
 656         };
 657 }
 658
 659 static void add_family_to_write_order(struct object_entry **wo,
 660                                       unsigned int *endp,
 661                                       struct object_entry *e)
 662 {
 663         struct object_entry *root;
 664
 665         for (root = e; DELTA(root); root = DELTA(root))
 666                 ; /* nothing */
 667         add_descendants_to_write_order(wo, endp, root);
 668 }
 669
 670 static void compute_layer_order(struct object_entry **wo, unsigned int *wo_end)
 671 {
 672         unsigned int i, last_untagged;
 673         struct object_entry *objects = to_pack.objects;
 674
 675         for (i = 0; i < to_pack.nr_objects; i++) {
 676                 if (objects[i].tagged)
 677                         break;
 678                 add_to_write_order(wo, wo_end, &objects[i]);
 679         }
 680         last_untagged = i;
 681
 682         /*
 683          * Then fill all the tagged tips.
 684          */
 685         for (; i < to_pack.nr_objects; i++) {
 686                 if (objects[i].tagged)
 687                         add_to_write_order(wo, wo_end, &objects[i]);
 688         }
 689
 690         /*
 691          * And then all remaining commits and tags.
 692          */
 693         for (i = last_untagged; i < to_pack.nr_objects; i++) {
 694                 if (oe_type(&objects[i]) != OBJ_COMMIT &&
 695                     oe_type(&objects[i]) != OBJ_TAG)
 696                         continue;
 697                 add_to_write_order(wo, wo_end, &objects[i]);
 698         }
 699
 700         /*
 701          * And then all the trees.
 702          */
 703         for (i = last_untagged; i < to_pack.nr_objects; i++) {
 704                 if (oe_type(&objects[i]) != OBJ_TREE)
 705                         continue;
 706                 add_to_write_order(wo, wo_end, &objects[i]);
 707         }
 708
 709         /*
 710          * Finally all the rest in really tight order
 711          */
 712         for (i = last_untagged; i < to_pack.nr_objects; i++) {
 713                 if (!objects[i].filled)
 714                         add_family_to_write_order(wo, wo_end, &objects[i]);
 715         }
 716 }
 717
 718 static struct object_entry **compute_write_order(void)
 719 {
 720         unsigned int i, wo_end;
 721
 722         struct object_entry **wo;
 723         struct object_entry *objects = to_pack.objects;
 724
 725         for (i = 0; i < to_pack.nr_objects; i++) {
 726                 objects[i].tagged = 0;
 727                 objects[i].filled = 0;
 728                 SET_DELTA_CHILD(&objects[i], NULL);
 729                 SET_DELTA_SIBLING(&objects[i], NULL);
 730         }
 731
 732         /*
 733          * Fully connect delta_child/delta_sibling network.
 734          * Make sure delta_sibling is sorted in the original
 735          * recency order.
 736          */
 737         for (i = to_pack.nr_objects; i > 0;) {
 738                 struct object_entry *e = &objects[--i];
 739                 if (!DELTA(e))
 740                         continue;
 741                 /* Mark me as the first child */
 742                 e->delta_sibling_idx = DELTA(e)->delta_child_idx;
 743                 SET_DELTA_CHILD(DELTA(e), e);
 744         }
 745
 746         /*
 747          * Mark objects that are at the tip of tags.
 748          */
 749         for_each_tag_ref(mark_tagged, NULL);
 750
 751         /*
 752          * Give the objects in the original recency order until
 753          * we see a tagged tip.
 754          */
 755         ALLOC_ARRAY(wo, to_pack.nr_objects);
 756         wo_end = 0;
 757
 758         compute_layer_order(wo, &wo_end);
 759
 760         if (wo_end != to_pack.nr_objects)
 761                 die("ordered %u objects, expected %"PRIu32, wo_end, to_pack.nr_objects);
 762
 763         return wo;
 764 }
 765
 766 static off_t write_reused_pack(struct hashfile *f)
 767 {
 768         unsigned char buffer[8192];
 769         off_t to_write, total;
 770         int fd;
 771
 772         if (!is_pack_valid(reuse_packfile))
 773                 die("packfile is invalid: %s", reuse_packfile->pack_name);
 774
 775         fd = git_open(reuse_packfile->pack_name);
 776         if (fd < 0)
 777                 die_errno("unable to open packfile for reuse: %s",
 778                           reuse_packfile->pack_name);
 779
 780         if (lseek(fd, sizeof(struct pack_header), SEEK_SET) == -1)
 781                 die_errno("unable to seek in reused packfile");
 782
 783         if (reuse_packfile_offset < 0)
 784                 reuse_packfile_offset = reuse_packfile->pack_size - the_hash_algo->rawsz;
 785
 786         total = to_write = reuse_packfile_offset - sizeof(struct pack_header);
 787
 788         while (to_write) {
 789                 int read_pack = xread(fd, buffer, sizeof(buffer));
 790
 791                 if (read_pack <= 0)
 792                         die_errno("unable to read from reused packfile");
 793
 794                 if (read_pack > to_write)
 795                         read_pack = to_write;
 796
 797                 hashwrite(f, buffer, read_pack);
 798                 to_write -= read_pack;
 799
 800                 /*
 801                  * We don't know the actual number of objects written,
 802                  * only how many bytes written, how many bytes total, and
 803                  * how many objects total. So we can fake it by pretending all
 804                  * objects we are writing are the same size. This gives us a
 805                  * smooth progress meter, and at the end it matches the true
 806                  * answer.
 807                  */
 808                 written = reuse_packfile_objects *
 809                                 (((double)(total - to_write)) / total);
 810                 display_progress(progress_state, written);
 811         }
 812
 813         close(fd);
 814         written = reuse_packfile_objects;
 815         display_progress(progress_state, written);
 816         return reuse_packfile_offset - sizeof(struct pack_header);
 817 }
 818
 819 static const char no_split_warning[] = N_(
 820 "disabling bitmap writing, packs are split due to pack.packSizeLimit"
 821 );
 822
 823 static void write_pack_file(void)
 824 {
 825         uint32_t i = 0, j;
 826         struct hashfile *f;
 827         off_t offset;
 828         uint32_t nr_remaining = nr_result;
 829         time_t last_mtime = 0;
 830         struct object_entry **write_order;
 831
 832         if (progress > pack_to_stdout)
 833                 progress_state = start_progress(_("Writing objects"), nr_result);
 834         ALLOC_ARRAY(written_list, to_pack.nr_objects);
 835         write_order = compute_write_order();
 836
 837         do {
 838                 struct object_id oid;
 839                 char *pack_tmp_name = NULL;
 840
 841                 if (pack_to_stdout)
 842                         f = hashfd_throughput(1, "<stdout>", progress_state);
 843                 else
 844                         f = create_tmp_packfile(&pack_tmp_name);
 845
 846                 offset = write_pack_header(f, nr_remaining);
 847
 848                 if (reuse_packfile) {
 849                         off_t packfile_size;
 850                         assert(pack_to_stdout);
 851
 852                         packfile_size = write_reused_pack(f);
 853                         offset += packfile_size;
 854                 }
 855
 856                 nr_written = 0;
 857                 for (; i < to_pack.nr_objects; i++) {
 858                         struct object_entry *e = write_order[i];
 859                         if (write_one(f, e, &offset) == WRITE_ONE_BREAK)
 860                                 break;
 861                         display_progress(progress_state, written);
 862                 }
 863
 864                 /*
 865                  * Did we write the wrong # entries in the header?
 866                  * If so, rewrite it like in fast-import
 867                  */
 868                 if (pack_to_stdout) {
 869                         finalize_hashfile(f, oid.hash, CSUM_HASH_IN_STREAM | CSUM_CLOSE);
 870                 } else if (nr_written == nr_remaining) {
 871                         finalize_hashfile(f, oid.hash, CSUM_HASH_IN_STREAM | CSUM_FSYNC | CSUM_CLOSE);
 872                 } else {
 873                         int fd = finalize_hashfile(f, oid.hash, 0);
 874                         fixup_pack_header_footer(fd, oid.hash, pack_tmp_name,
 875                                                  nr_written, oid.hash, offset);
 876                         close(fd);
 877                         if (write_bitmap_index) {
 878                                 warning(_(no_split_warning));
 879                                 write_bitmap_index = 0;
 880                         }
 881                 }
 882
 883                 if (!pack_to_stdout) {
 884                         struct stat st;
 885                         struct strbuf tmpname = STRBUF_INIT;
 886
 887                         /*
 888                          * Packs are runtime accessed in their mtime
 889                          * order since newer packs are more likely to contain
 890                          * younger objects.  So if we are creating multiple
 891                          * packs then we should modify the mtime of later ones
 892                          * to preserve this property.
 893                          */
 894                         if (stat(pack_tmp_name, &st) < 0) {
 895                                 warning_errno("failed to stat %s", pack_tmp_name);
 896                         } else if (!last_mtime) {
 897                                 last_mtime = st.st_mtime;
 898                         } else {
 899                                 struct utimbuf utb;
 900                                 utb.actime = st.st_atime;
 901                                 utb.modtime = --last_mtime;
 902                                 if (utime(pack_tmp_name, &utb) < 0)
 903                                         warning_errno("failed utime() on %s", pack_tmp_name);
 904                         }
 905
 906                         strbuf_addf(&tmpname, "%s-", base_name);
 907
 908                         if (write_bitmap_index) {
 909                                 bitmap_writer_set_checksum(oid.hash);
 910                                 bitmap_writer_build_type_index(
 911                                         &to_pack, written_list, nr_written);
 912                         }
 913
 914                         finish_tmp_packfile(&tmpname, pack_tmp_name,
 915                                             written_list, nr_written,
 916                                             &pack_idx_opts, oid.hash);
 917
 918                         if (write_bitmap_index) {
 919                                 strbuf_addf(&tmpname, "%s.bitmap", oid_to_hex(&oid));
 920
 921                                 stop_progress(&progress_state);
 922
 923                                 bitmap_writer_show_progress(progress);
 924                                 bitmap_writer_reuse_bitmaps(&to_pack);
 925                                 bitmap_writer_select_commits(indexed_commits, indexed_commits_nr, -1);
 926                                 bitmap_writer_build(&to_pack);
 927                                 bitmap_writer_finish(written_list, nr_written,
 928                                                      tmpname.buf, write_bitmap_options);
 929                                 write_bitmap_index = 0;
 930                         }
 931
 932                         strbuf_release(&tmpname);
 933                         free(pack_tmp_name);
 934                         puts(oid_to_hex(&oid));
 935                 }
 936
 937                 /* mark written objects as written to previous pack */
 938                 for (j = 0; j < nr_written; j++) {
 939                         written_list[j]->offset = (off_t)-1;
 940                 }
 941                 nr_remaining -= nr_written;
 942         } while (nr_remaining && i < to_pack.nr_objects);
 943
 944         free(written_list);
 945         free(write_order);
 946         stop_progress(&progress_state);
 947         if (written != nr_result)
 948                 die("wrote %"PRIu32" objects while expecting %"PRIu32,
 949                         written, nr_result);
 950 }
 951
 952 static int no_try_delta(const char *path)
 953 {
 954         static struct attr_check *check;
 955
 956         if (!check)
 957                 check = attr_check_initl("delta", NULL);
 958         if (git_check_attr(path, check))
 959                 return 0;
 960         if (ATTR_FALSE(check->items[0].value))
 961                 return 1;
 962         return 0;
 963 }
 964
 965 /*
 966  * When adding an object, check whether we have already added it
 967  * to our packing list. If so, we can skip. However, if we are
 968  * being asked to excludei t, but the previous mention was to include
 969  * it, make sure to adjust its flags and tweak our numbers accordingly.
 970  *
 971  * As an optimization, we pass out the index position where we would have
 972  * found the item, since that saves us from having to look it up again a
 973  * few lines later when we want to add the new entry.
 974  */
 975 static int have_duplicate_entry(const struct object_id *oid,
 976                                 int exclude,
 977                                 uint32_t *index_pos)
 978 {
 979         struct object_entry *entry;
 980
 981         entry = packlist_find(&to_pack, oid->hash, index_pos);
 982         if (!entry)
 983                 return 0;
 984
 985         if (exclude) {
 986                 if (!entry->preferred_base)
 987                         nr_result--;
 988                 entry->preferred_base = 1;
 989         }
 990
 991         return 1;
 992 }
 993
 994 static int want_found_object(int exclude, struct packed_git *p)
 995 {
 996         if (exclude)
 997                 return 1;
 998         if (incremental)
 999                 return 0;
1000
1001         /*
1002          * When asked to do --local (do not include an object that appears in a
1003          * pack we borrow from elsewhere) or --honor-pack-keep (do not include
1004          * an object that appears in a pack marked with .keep), finding a pack
1005          * that matches the criteria is sufficient for us to decide to omit it.
1006          * However, even if this pack does not satisfy the criteria, we need to
1007          * make sure no copy of this object appears in _any_ pack that makes us
1008          * to omit the object, so we need to check all the packs.
1009          *
1010          * We can however first check whether these options can possible matter;
1011          * if they do not matter we know we want the object in generated pack.
1012          * Otherwise, we signal "-1" at the end to tell the caller that we do
1013          * not know either way, and it needs to check more packs.
1014          */
1015         if (!ignore_packed_keep_on_disk &&
1016             !ignore_packed_keep_in_core &&
1017             (!local || !have_non_local_packs))
1018                 return 1;
1019
1020         if (local && !p->pack_local)
1021                 return 0;
1022         if (p->pack_local &&
1023             ((ignore_packed_keep_on_disk && p->pack_keep) ||
1024              (ignore_packed_keep_in_core && p->pack_keep_in_core)))
1025                 return 0;
1026
1027         /* we don't know yet; keep looking for more packs */
1028         return -1;
1029 }
1030
1031 /*
1032  * Check whether we want the object in the pack (e.g., we do not want
1033  * objects found in non-local stores if the "--local" option was used).
1034  *
1035  * If the caller already knows an existing pack it wants to take the object
1036  * from, that is passed in *found_pack and *found_offset; otherwise this
1037  * function finds if there is any pack that has the object and returns the pack
1038  * and its offset in these variables.
1039  */
1040 static int want_object_in_pack(const struct object_id *oid,
1041                                int exclude,
1042                                struct packed_git **found_pack,
1043                                off_t *found_offset)
1044 {
1045         int want;
1046         struct list_head *pos;
1047
1048         if (!exclude && local && has_loose_object_nonlocal(oid))
1049                 return 0;
1050
1051         /*
1052          * If we already know the pack object lives in, start checks from that
1053          * pack - in the usual case when neither --local was given nor .keep files
1054          * are present we will determine the answer right now.
1055          */
1056         if (*found_pack) {
1057                 want = want_found_object(exclude, *found_pack);
1058                 if (want != -1)
1059                         return want;
1060         }
1061         list_for_each(pos, get_packed_git_mru(the_repository)) {
1062                 struct packed_git *p = list_entry(pos, struct packed_git, mru);
1063                 off_t offset;
1064
1065                 if (p == *found_pack)
1066                         offset = *found_offset;
1067                 else
1068                         offset = find_pack_entry_one(oid->hash, p);
1069
1070                 if (offset) {
1071                         if (!*found_pack) {
1072                                 if (!is_pack_valid(p))
1073                                         continue;
1074                                 *found_offset = offset;
1075                                 *found_pack = p;
1076                         }
1077                         want = want_found_object(exclude, p);
1078                         if (!exclude && want > 0)
1079                                 list_move(&p->mru,
1080                                           get_packed_git_mru(the_repository));
1081                         if (want != -1)
1082                                 return want;
1083                 }
1084         }
1085
1086         return 1;
1087 }
1088
1089 static void create_object_entry(const struct object_id *oid,
1090                                 enum object_type type,
1091                                 uint32_t hash,
1092                                 int exclude,
1093                                 int no_try_delta,
1094                                 uint32_t index_pos,
1095                                 struct packed_git *found_pack,
1096                                 off_t found_offset)
1097 {
1098         struct object_entry *entry;
1099
1100         entry = packlist_alloc(&to_pack, oid->hash, index_pos);
1101         entry->hash = hash;
1102         oe_set_type(entry, type);
1103         if (exclude)
1104                 entry->preferred_base = 1;
1105         else
1106                 nr_result++;
1107         if (found_pack) {
1108                 oe_set_in_pack(&to_pack, entry, found_pack);
1109                 entry->in_pack_offset = found_offset;
1110         }
1111
1112         entry->no_try_delta = no_try_delta;
1113 }
1114
1115 static const char no_closure_warning[] = N_(
1116 "disabling bitmap writing, as some objects are not being packed"
1117 );
1118
1119 static int add_object_entry(const struct object_id *oid, enum object_type type,
1120                             const char *name, int exclude)
1121 {
1122         struct packed_git *found_pack = NULL;
1123         off_t found_offset = 0;
1124         uint32_t index_pos;
1125
1126         display_progress(progress_state, ++nr_seen);
1127
1128         if (have_duplicate_entry(oid, exclude, &index_pos))
1129                 return 0;
1130
1131         if (!want_object_in_pack(oid, exclude, &found_pack, &found_offset)) {
1132                 /* The pack is missing an object, so it will not have closure */
1133                 if (write_bitmap_index) {
1134                         warning(_(no_closure_warning));
1135                         write_bitmap_index = 0;
1136                 }
1137                 return 0;
1138         }
1139
1140         create_object_entry(oid, type, pack_name_hash(name),
1141                             exclude, name && no_try_delta(name),
1142                             index_pos, found_pack, found_offset);
1143         return 1;
1144 }
1145
1146 static int add_object_entry_from_bitmap(const struct object_id *oid,
1147                                         enum object_type type,
1148                                         int flags, uint32_t name_hash,
1149                                         struct packed_git *pack, off_t offset)
1150 {
1151         uint32_t index_pos;
1152
1153         display_progress(progress_state, ++nr_seen);
1154
1155         if (have_duplicate_entry(oid, 0, &index_pos))
1156                 return 0;
1157
1158         if (!want_object_in_pack(oid, 0, &pack, &offset))
1159                 return 0;
1160
1161         create_object_entry(oid, type, name_hash, 0, 0, index_pos, pack, offset);
1162         return 1;
1163 }
1164
1165 struct pbase_tree_cache {
1166         struct object_id oid;
1167         int ref;
1168         int temporary;
1169         void *tree_data;
1170         unsigned long tree_size;
1171 };
1172
1173 static struct pbase_tree_cache *(pbase_tree_cache[256]);
1174 static int pbase_tree_cache_ix(const struct object_id *oid)
1175 {
1176         return oid->hash[0] % ARRAY_SIZE(pbase_tree_cache);
1177 }
1178 static int pbase_tree_cache_ix_incr(int ix)
1179 {
1180         return (ix+1) % ARRAY_SIZE(pbase_tree_cache);
1181 }
1182
1183 static struct pbase_tree {
1184         struct pbase_tree *next;
1185         /* This is a phony "cache" entry; we are not
1186          * going to evict it or find it through _get()
1187          * mechanism -- this is for the toplevel node that
1188          * would almost always change with any commit.
1189          */
1190         struct pbase_tree_cache pcache;
1191 } *pbase_tree;
1192
1193 static struct pbase_tree_cache *pbase_tree_get(const struct object_id *oid)
1194 {
1195         struct pbase_tree_cache *ent, *nent;
1196         void *data;
1197         unsigned long size;
1198         enum object_type type;
1199         int neigh;
1200         int my_ix = pbase_tree_cache_ix(oid);
1201         int available_ix = -1;
1202
1203         /* pbase-tree-cache acts as a limited hashtable.
1204          * your object will be found at your index or within a few
1205          * slots after that slot if it is cached.
1206          */
1207         for (neigh = 0; neigh < 8; neigh++) {
1208                 ent = pbase_tree_cache[my_ix];
1209                 if (ent && !oidcmp(&ent->oid, oid)) {
1210                         ent->ref++;
1211                         return ent;
1212                 }
1213                 else if (((available_ix < 0) && (!ent || !ent->ref)) ||
1214                          ((0 <= available_ix) &&
1215                           (!ent && pbase_tree_cache[available_ix])))
1216                         available_ix = my_ix;
1217                 if (!ent)
1218                         break;
1219                 my_ix = pbase_tree_cache_ix_incr(my_ix);
1220         }
1221
1222         /* Did not find one.  Either we got a bogus request or
1223          * we need to read and perhaps cache.
1224          */
1225         data = read_object_file(oid, &type, &size);
1226         if (!data)
1227                 return NULL;
1228         if (type != OBJ_TREE) {
1229                 free(data);
1230                 return NULL;
1231         }
1232
1233         /* We need to either cache or return a throwaway copy */
1234
1235         if (available_ix < 0)
1236                 ent = NULL;
1237         else {
1238                 ent = pbase_tree_cache[available_ix];
1239                 my_ix = available_ix;
1240         }
1241
1242         if (!ent) {
1243                 nent = xmalloc(sizeof(*nent));
1244                 nent->temporary = (available_ix < 0);
1245         }
1246         else {
1247                 /* evict and reuse */
1248                 free(ent->tree_data);
1249                 nent = ent;
1250         }
1251         oidcpy(&nent->oid, oid);
1252         nent->tree_data = data;
1253         nent->tree_size = size;
1254         nent->ref = 1;
1255         if (!nent->temporary)
1256                 pbase_tree_cache[my_ix] = nent;
1257         return nent;
1258 }
1259
1260 static void pbase_tree_put(struct pbase_tree_cache *cache)
1261 {
1262         if (!cache->temporary) {
1263                 cache->ref--;
1264                 return;
1265         }
1266         free(cache->tree_data);
1267         free(cache);
1268 }
1269
1270 static int name_cmp_len(const char *name)
1271 {
1272         int i;
1273         for (i = 0; name[i] && name[i] != '\n' && name[i] != '/'; i++)
1274                 ;
1275         return i;
1276 }
1277
1278 static void add_pbase_object(struct tree_desc *tree,
1279                              const char *name,
1280                              int cmplen,
1281                              const char *fullname)
1282 {
1283         struct name_entry entry;
1284         int cmp;
1285
1286         while (tree_entry(tree,&entry)) {
1287                 if (S_ISGITLINK(entry.mode))
1288                         continue;
1289                 cmp = tree_entry_len(&entry) != cmplen ? 1 :
1290                       memcmp(name, entry.path, cmplen);
1291                 if (cmp > 0)
1292                         continue;
1293                 if (cmp < 0)
1294                         return;
1295                 if (name[cmplen] != '/') {
1296                         add_object_entry(entry.oid,
1297                                          object_type(entry.mode),
1298                                          fullname, 1);
1299                         return;
1300                 }
1301                 if (S_ISDIR(entry.mode)) {
1302                         struct tree_desc sub;
1303                         struct pbase_tree_cache *tree;
1304                         const char *down = name+cmplen+1;
1305                         int downlen = name_cmp_len(down);
1306
1307                         tree = pbase_tree_get(entry.oid);
1308                         if (!tree)
1309                                 return;
1310                         init_tree_desc(&sub, tree->tree_data, tree->tree_size);
1311
1312                         add_pbase_object(&sub, down, downlen, fullname);
1313                         pbase_tree_put(tree);
1314                 }
1315         }
1316 }
1317
1318 static unsigned *done_pbase_paths;
1319 static int done_pbase_paths_num;
1320 static int done_pbase_paths_alloc;
1321 static int done_pbase_path_pos(unsigned hash)
1322 {
1323         int lo = 0;
1324         int hi = done_pbase_paths_num;
1325         while (lo < hi) {
1326                 int mi = lo + (hi - lo) / 2;
1327                 if (done_pbase_paths[mi] == hash)
1328                         return mi;
1329                 if (done_pbase_paths[mi] < hash)
1330                         hi = mi;
1331                 else
1332                         lo = mi + 1;
1333         }
1334         return -lo-1;
1335 }
1336
1337 static int check_pbase_path(unsigned hash)
1338 {
1339         int pos = done_pbase_path_pos(hash);
1340         if (0 <= pos)
1341                 return 1;
1342         pos = -pos - 1;
1343         ALLOC_GROW(done_pbase_paths,
1344                    done_pbase_paths_num + 1,
1345                    done_pbase_paths_alloc);
1346         done_pbase_paths_num++;
1347         if (pos < done_pbase_paths_num)
1348                 MOVE_ARRAY(done_pbase_paths + pos + 1, done_pbase_paths + pos,
1349                            done_pbase_paths_num - pos - 1);
1350         done_pbase_paths[pos] = hash;
1351         return 0;
1352 }
1353
1354 static void add_preferred_base_object(const char *name)
1355 {
1356         struct pbase_tree *it;
1357         int cmplen;
1358         unsigned hash = pack_name_hash(name);
1359
1360         if (!num_preferred_base || check_pbase_path(hash))
1361                 return;
1362
1363         cmplen = name_cmp_len(name);
1364         for (it = pbase_tree; it; it = it->next) {
1365                 if (cmplen == 0) {
1366                         add_object_entry(&it->pcache.oid, OBJ_TREE, NULL, 1);
1367                 }
1368                 else {
1369                         struct tree_desc tree;
1370                         init_tree_desc(&tree, it->pcache.tree_data, it->pcache.tree_size);
1371                         add_pbase_object(&tree, name, cmplen, name);
1372                 }
1373         }
1374 }
1375
1376 static void add_preferred_base(struct object_id *oid)
1377 {
1378         struct pbase_tree *it;
1379         void *data;
1380         unsigned long size;
1381         struct object_id tree_oid;
1382
1383         if (window <= num_preferred_base++)
1384                 return;
1385
1386         data = read_object_with_reference(oid, tree_type, &size, &tree_oid);
1387         if (!data)
1388                 return;
1389
1390         for (it = pbase_tree; it; it = it->next) {
1391                 if (!oidcmp(&it->pcache.oid, &tree_oid)) {
1392                         free(data);
1393                         return;
1394                 }
1395         }
1396
1397         it = xcalloc(1, sizeof(*it));
1398         it->next = pbase_tree;
1399         pbase_tree = it;
1400
1401         oidcpy(&it->pcache.oid, &tree_oid);
1402         it->pcache.tree_data = data;
1403         it->pcache.tree_size = size;
1404 }
1405
1406 static void cleanup_preferred_base(void)
1407 {
1408         struct pbase_tree *it;
1409         unsigned i;
1410
1411         it = pbase_tree;
1412         pbase_tree = NULL;
1413         while (it) {
1414                 struct pbase_tree *tmp = it;
1415                 it = tmp->next;
1416                 free(tmp->pcache.tree_data);
1417                 free(tmp);
1418         }
1419
1420         for (i = 0; i < ARRAY_SIZE(pbase_tree_cache); i++) {
1421                 if (!pbase_tree_cache[i])
1422                         continue;
1423                 free(pbase_tree_cache[i]->tree_data);
1424                 FREE_AND_NULL(pbase_tree_cache[i]);
1425         }
1426
1427         FREE_AND_NULL(done_pbase_paths);
1428         done_pbase_paths_num = done_pbase_paths_alloc = 0;
1429 }
1430
1431 static void check_object(struct object_entry *entry)
1432 {
1433         unsigned long canonical_size;
1434
1435         if (IN_PACK(entry)) {
1436                 struct packed_git *p = IN_PACK(entry);
1437                 struct pack_window *w_curs = NULL;
1438                 const unsigned char *base_ref = NULL;
1439                 struct object_entry *base_entry;
1440                 unsigned long used, used_0;
1441                 unsigned long avail;
1442                 off_t ofs;
1443                 unsigned char *buf, c;
1444                 enum object_type type;
1445                 unsigned long in_pack_size;
1446
1447                 buf = use_pack(p, &w_curs, entry->in_pack_offset, &avail);
1448
1449                 /*
1450                  * We want in_pack_type even if we do not reuse delta
1451                  * since non-delta representations could still be reused.
1452                  */
1453                 used = unpack_object_header_buffer(buf, avail,
1454                                                    &type,
1455                                                    &in_pack_size);
1456                 if (used == 0)
1457                         goto give_up;
1458
1459                 if (type < 0)
1460                         BUG("invalid type %d", type);
1461                 entry->in_pack_type = type;
1462
1463                 /*
1464                  * Determine if this is a delta and if so whether we can
1465                  * reuse it or not.  Otherwise let's find out as cheaply as
1466                  * possible what the actual type and size for this object is.
1467                  */
1468                 switch (entry->in_pack_type) {
1469                 default:
1470                         /* Not a delta hence we've already got all we need. */
1471                         oe_set_type(entry, entry->in_pack_type);
1472                         SET_SIZE(entry, in_pack_size);
1473                         entry->in_pack_header_size = used;
1474                         if (oe_type(entry) < OBJ_COMMIT || oe_type(entry) > OBJ_BLOB)
1475                                 goto give_up;
1476                         unuse_pack(&w_curs);
1477                         return;
1478                 case OBJ_REF_DELTA:
1479                         if (reuse_delta && !entry->preferred_base)
1480                                 base_ref = use_pack(p, &w_curs,
1481                                                 entry->in_pack_offset + used, NULL);
1482                         entry->in_pack_header_size = used + the_hash_algo->rawsz;
1483                         break;
1484                 case OBJ_OFS_DELTA:
1485                         buf = use_pack(p, &w_curs,
1486                                        entry->in_pack_offset + used, NULL);
1487                         used_0 = 0;
1488                         c = buf[used_0++];
1489                         ofs = c & 127;
1490                         while (c & 128) {
1491                                 ofs += 1;
1492                                 if (!ofs || MSB(ofs, 7)) {
1493                                         error("delta base offset overflow in pack for %s",
1494                                               oid_to_hex(&entry->idx.oid));
1495                                         goto give_up;
1496                                 }
1497                                 c = buf[used_0++];
1498                                 ofs = (ofs << 7) + (c & 127);
1499                         }
1500                         ofs = entry->in_pack_offset - ofs;
1501                         if (ofs <= 0 || ofs >= entry->in_pack_offset) {
1502                                 error("delta base offset out of bound for %s",
1503                                       oid_to_hex(&entry->idx.oid));
1504                                 goto give_up;
1505                         }
1506                         if (reuse_delta && !entry->preferred_base) {
1507                                 struct revindex_entry *revidx;
1508                                 revidx = find_pack_revindex(p, ofs);
1509                                 if (!revidx)
1510                                         goto give_up;
1511                                 base_ref = nth_packed_object_sha1(p, revidx->nr);
1512                         }
1513                         entry->in_pack_header_size = used + used_0;
1514                         break;
1515                 }
1516
1517                 if (base_ref && (base_entry = packlist_find(&to_pack, base_ref, NULL))) {
1518                         /*
1519                          * If base_ref was set above that means we wish to
1520                          * reuse delta data, and we even found that base
1521                          * in the list of objects we want to pack. Goodie!
1522                          *
1523                          * Depth value does not matter - find_deltas() will
1524                          * never consider reused delta as the base object to
1525                          * deltify other objects against, in order to avoid
1526                          * circular deltas.
1527                          */
1528                         oe_set_type(entry, entry->in_pack_type);
1529                         SET_SIZE(entry, in_pack_size); /* delta size */
1530                         SET_DELTA(entry, base_entry);
1531                         SET_DELTA_SIZE(entry, in_pack_size);
1532                         entry->delta_sibling_idx = base_entry->delta_child_idx;
1533                         SET_DELTA_CHILD(base_entry, entry);
1534                         unuse_pack(&w_curs);
1535                         return;
1536                 }
1537
1538                 if (oe_type(entry)) {
1539                         off_t delta_pos;
1540
1541                         /*
1542                          * This must be a delta and we already know what the
1543                          * final object type is.  Let's extract the actual
1544                          * object size from the delta header.
1545                          */
1546                         delta_pos = entry->in_pack_offset + entry->in_pack_header_size;
1547                         canonical_size = get_size_from_delta(p, &w_curs, delta_pos);
1548                         if (canonical_size == 0)
1549                                 goto give_up;
1550                         SET_SIZE(entry, canonical_size);
1551                         unuse_pack(&w_curs);
1552                         return;
1553                 }
1554
1555                 /*
1556                  * No choice but to fall back to the recursive delta walk
1557                  * with sha1_object_info() to find about the object type
1558                  * at this point...
1559                  */
1560                 give_up:
1561                 unuse_pack(&w_curs);
1562         }
1563
1564         oe_set_type(entry,
1565                     oid_object_info(the_repository, &entry->idx.oid, &canonical_size));
1566         if (entry->type_valid) {
1567                 SET_SIZE(entry, canonical_size);
1568         } else {
1569                 /*
1570                  * Bad object type is checked in prepare_pack().  This is
1571                  * to permit a missing preferred base object to be ignored
1572                  * as a preferred base.  Doing so can result in a larger
1573                  * pack file, but the transfer will still take place.
1574                  */
1575         }
1576 }
1577
1578 static int pack_offset_sort(const void *_a, const void *_b)
1579 {
1580         const struct object_entry *a = *(struct object_entry **)_a;
1581         const struct object_entry *b = *(struct object_entry **)_b;
1582         const struct packed_git *a_in_pack = IN_PACK(a);
1583         const struct packed_git *b_in_pack = IN_PACK(b);
1584
1585         /* avoid filesystem trashing with loose objects */
1586         if (!a_in_pack && !b_in_pack)
1587                 return oidcmp(&a->idx.oid, &b->idx.oid);
1588
1589         if (a_in_pack < b_in_pack)
1590                 return -1;
1591         if (a_in_pack > b_in_pack)
1592                 return 1;
1593         return a->in_pack_offset < b->in_pack_offset ? -1 :
1594                         (a->in_pack_offset > b->in_pack_offset);
1595 }
1596
1597 /*
1598  * Drop an on-disk delta we were planning to reuse. Naively, this would
1599  * just involve blanking out the "delta" field, but we have to deal
1600  * with some extra book-keeping:
1601  *
1602  *   1. Removing ourselves from the delta_sibling linked list.
1603  *
1604  *   2. Updating our size/type to the non-delta representation. These were
1605  *      either not recorded initially (size) or overwritten with the delta type
1606  *      (type) when check_object() decided to reuse the delta.
1607  *
1608  *   3. Resetting our delta depth, as we are now a base object.
1609  */
1610 static void drop_reused_delta(struct object_entry *entry)
1611 {
1612         unsigned *idx = &to_pack.objects[entry->delta_idx - 1].delta_child_idx;
1613         struct object_info oi = OBJECT_INFO_INIT;
1614         enum object_type type;
1615         unsigned long size;
1616
1617         while (*idx) {
1618                 struct object_entry *oe = &to_pack.objects[*idx - 1];
1619
1620                 if (oe == entry)
1621                         *idx = oe->delta_sibling_idx;
1622                 else
1623                         idx = &oe->delta_sibling_idx;
1624         }
1625         SET_DELTA(entry, NULL);
1626         entry->depth = 0;
1627
1628         oi.sizep = &size;
1629         oi.typep = &type;
1630         if (packed_object_info(the_repository, IN_PACK(entry), entry->in_pack_offset, &oi) < 0) {
1631                 /*
1632                  * We failed to get the info from this pack for some reason;
1633                  * fall back to sha1_object_info, which may find another copy.
1634                  * And if that fails, the error will be recorded in oe_type(entry)
1635                  * and dealt with in prepare_pack().
1636                  */
1637                 oe_set_type(entry,
1638                             oid_object_info(the_repository, &entry->idx.oid, &size));
1639         } else {
1640                 oe_set_type(entry, type);
1641         }
1642         SET_SIZE(entry, size);
1643 }
1644
1645 /*
1646  * Follow the chain of deltas from this entry onward, throwing away any links
1647  * that cause us to hit a cycle (as determined by the DFS state flags in
1648  * the entries).
1649  *
1650  * We also detect too-long reused chains that would violate our --depth
1651  * limit.
1652  */
1653 static void break_delta_chains(struct object_entry *entry)
1654 {
1655         /*
1656          * The actual depth of each object we will write is stored as an int,
1657          * as it cannot exceed our int "depth" limit. But before we break
1658          * changes based no that limit, we may potentially go as deep as the
1659          * number of objects, which is elsewhere bounded to a uint32_t.
1660          */
1661         uint32_t total_depth;
1662         struct object_entry *cur, *next;
1663
1664         for (cur = entry, total_depth = 0;
1665              cur;
1666              cur = DELTA(cur), total_depth++) {
1667                 if (cur->dfs_state == DFS_DONE) {
1668                         /*
1669                          * We've already seen this object and know it isn't
1670                          * part of a cycle. We do need to append its depth
1671                          * to our count.
1672                          */
1673                         total_depth += cur->depth;
1674                         break;
1675                 }
1676
1677                 /*
1678                  * We break cycles before looping, so an ACTIVE state (or any
1679                  * other cruft which made its way into the state variable)
1680                  * is a bug.
1681                  */
1682                 if (cur->dfs_state != DFS_NONE)
1683                         BUG("confusing delta dfs state in first pass: %d",
1684                             cur->dfs_state);
1685
1686                 /*
1687                  * Now we know this is the first time we've seen the object. If
1688                  * it's not a delta, we're done traversing, but we'll mark it
1689                  * done to save time on future traversals.
1690                  */
1691                 if (!DELTA(cur)) {
1692                         cur->dfs_state = DFS_DONE;
1693                         break;
1694                 }
1695
1696                 /*
1697                  * Mark ourselves as active and see if the next step causes
1698                  * us to cycle to another active object. It's important to do
1699                  * this _before_ we loop, because it impacts where we make the
1700                  * cut, and thus how our total_depth counter works.
1701                  * E.g., We may see a partial loop like:
1702                  *
1703                  *   A -> B -> C -> D -> B
1704                  *
1705                  * Cutting B->C breaks the cycle. But now the depth of A is
1706                  * only 1, and our total_depth counter is at 3. The size of the
1707                  * error is always one less than the size of the cycle we
1708                  * broke. Commits C and D were "lost" from A's chain.
1709                  *
1710                  * If we instead cut D->B, then the depth of A is correct at 3.
1711                  * We keep all commits in the chain that we examined.
1712                  */
1713                 cur->dfs_state = DFS_ACTIVE;
1714                 if (DELTA(cur)->dfs_state == DFS_ACTIVE) {
1715                         drop_reused_delta(cur);
1716                         cur->dfs_state = DFS_DONE;
1717                         break;
1718                 }
1719         }
1720
1721         /*
1722          * And now that we've gone all the way to the bottom of the chain, we
1723          * need to clear the active flags and set the depth fields as
1724          * appropriate. Unlike the loop above, which can quit when it drops a
1725          * delta, we need to keep going to look for more depth cuts. So we need
1726          * an extra "next" pointer to keep going after we reset cur->delta.
1727          */
1728         for (cur = entry; cur; cur = next) {
1729                 next = DELTA(cur);
1730
1731                 /*
1732                  * We should have a chain of zero or more ACTIVE states down to
1733                  * a final DONE. We can quit after the DONE, because either it
1734                  * has no bases, or we've already handled them in a previous
1735                  * call.
1736                  */
1737                 if (cur->dfs_state == DFS_DONE)
1738                         break;
1739                 else if (cur->dfs_state != DFS_ACTIVE)
1740                         BUG("confusing delta dfs state in second pass: %d",
1741                             cur->dfs_state);
1742
1743                 /*
1744                  * If the total_depth is more than depth, then we need to snip
1745                  * the chain into two or more smaller chains that don't exceed
1746                  * the maximum depth. Most of the resulting chains will contain
1747                  * (depth + 1) entries (i.e., depth deltas plus one base), and
1748                  * the last chain (i.e., the one containing entry) will contain
1749                  * whatever entries are left over, namely
1750                  * (total_depth % (depth + 1)) of them.
1751                  *
1752                  * Since we are iterating towards decreasing depth, we need to
1753                  * decrement total_depth as we go, and we need to write to the
1754                  * entry what its final depth will be after all of the
1755                  * snipping. Since we're snipping into chains of length (depth
1756                  * + 1) entries, the final depth of an entry will be its
1757                  * original depth modulo (depth + 1). Any time we encounter an
1758                  * entry whose final depth is supposed to be zero, we snip it
1759                  * from its delta base, thereby making it so.
1760                  */
1761                 cur->depth = (total_depth--) % (depth + 1);
1762                 if (!cur->depth)
1763                         drop_reused_delta(cur);
1764
1765                 cur->dfs_state = DFS_DONE;
1766         }
1767 }
1768
1769 static void get_object_details(void)
1770 {
1771         uint32_t i;
1772         struct object_entry **sorted_by_offset;
1773
1774         if (progress)
1775                 progress_state = start_progress(_("Counting objects"),
1776                                                 to_pack.nr_objects);
1777
1778         sorted_by_offset = xcalloc(to_pack.nr_objects, sizeof(struct object_entry *));
1779         for (i = 0; i < to_pack.nr_objects; i++)
1780                 sorted_by_offset[i] = to_pack.objects + i;
1781         QSORT(sorted_by_offset, to_pack.nr_objects, pack_offset_sort);
1782
1783         for (i = 0; i < to_pack.nr_objects; i++) {
1784                 struct object_entry *entry = sorted_by_offset[i];
1785                 check_object(entry);
1786                 if (entry->type_valid &&
1787                     oe_size_greater_than(&to_pack, entry, big_file_threshold))
1788                         entry->no_try_delta = 1;
1789                 display_progress(progress_state, i + 1);
1790         }
1791         stop_progress(&progress_state);
1792
1793         /*
1794          * This must happen in a second pass, since we rely on the delta
1795          * information for the whole list being completed.
1796          */
1797         for (i = 0; i < to_pack.nr_objects; i++)
1798                 break_delta_chains(&to_pack.objects[i]);
1799
1800         free(sorted_by_offset);
1801 }
1802
1803 /*
1804  * We search for deltas in a list sorted by type, by filename hash, and then
1805  * by size, so that we see progressively smaller and smaller files.
1806  * That's because we prefer deltas to be from the bigger file
1807  * to the smaller -- deletes are potentially cheaper, but perhaps
1808  * more importantly, the bigger file is likely the more recent
1809  * one.  The deepest deltas are therefore the oldest objects which are
1810  * less susceptible to be accessed often.
1811  */
1812 static int type_size_sort(const void *_a, const void *_b)
1813 {
1814         const struct object_entry *a = *(struct object_entry **)_a;
1815         const struct object_entry *b = *(struct object_entry **)_b;
1816         enum object_type a_type = oe_type(a);
1817         enum object_type b_type = oe_type(b);
1818         unsigned long a_size = SIZE(a);
1819         unsigned long b_size = SIZE(b);
1820
1821         if (a_type > b_type)
1822                 return -1;
1823         if (a_type < b_type)
1824                 return 1;
1825         if (a->hash > b->hash)
1826                 return -1;
1827         if (a->hash < b->hash)
1828                 return 1;
1829         if (a->preferred_base > b->preferred_base)
1830                 return -1;
1831         if (a->preferred_base < b->preferred_base)
1832                 return 1;
1833         if (a_size > b_size)
1834                 return -1;
1835         if (a_size < b_size)
1836                 return 1;
1837         return a < b ? -1 : (a > b);  /* newest first */
1838 }
1839
1840 struct unpacked {
1841         struct object_entry *entry;
1842         void *data;
1843         struct delta_index *index;
1844         unsigned depth;
1845 };
1846
1847 static int delta_cacheable(unsigned long src_size, unsigned long trg_size,
1848                            unsigned long delta_size)
1849 {
1850         if (max_delta_cache_size && delta_cache_size + delta_size > max_delta_cache_size)
1851                 return 0;
1852
1853         if (delta_size < cache_max_small_delta_size)
1854                 return 1;
1855
1856         /* cache delta, if objects are large enough compared to delta size */
1857         if ((src_size >> 20) + (trg_size >> 21) > (delta_size >> 10))
1858                 return 1;
1859
1860         return 0;
1861 }
1862
1863 #ifndef NO_PTHREADS
1864
1865 static pthread_mutex_t read_mutex;
1866 #define read_lock()             pthread_mutex_lock(&read_mutex)
1867 #define read_unlock()           pthread_mutex_unlock(&read_mutex)
1868
1869 static pthread_mutex_t cache_mutex;
1870 #define cache_lock()            pthread_mutex_lock(&cache_mutex)
1871 #define cache_unlock()          pthread_mutex_unlock(&cache_mutex)
1872
1873 static pthread_mutex_t progress_mutex;
1874 #define progress_lock()         pthread_mutex_lock(&progress_mutex)
1875 #define progress_unlock()       pthread_mutex_unlock(&progress_mutex)
1876
1877 #else
1878
1879 #define read_lock()             (void)0
1880 #define read_unlock()           (void)0
1881 #define cache_lock()            (void)0
1882 #define cache_unlock()          (void)0
1883 #define progress_lock()         (void)0
1884 #define progress_unlock()       (void)0
1885
1886 #endif
1887
1888 /*
1889  * Return the size of the object without doing any delta
1890  * reconstruction (so non-deltas are true object sizes, but deltas
1891  * return the size of the delta data).
1892  */
1893 unsigned long oe_get_size_slow(struct packing_data *pack,
1894                                const struct object_entry *e)
1895 {
1896         struct packed_git *p;
1897         struct pack_window *w_curs;
1898         unsigned char *buf;
1899         enum object_type type;
1900         unsigned long used, avail, size;
1901
1902         if (e->type_ != OBJ_OFS_DELTA && e->type_ != OBJ_REF_DELTA) {
1903                 read_lock();
1904                 if (oid_object_info(the_repository, &e->idx.oid, &size) < 0)
1905                         die(_("unable to get size of %s"),
1906                             oid_to_hex(&e->idx.oid));
1907                 read_unlock();
1908                 return size;
1909         }
1910
1911         p = oe_in_pack(pack, e);
1912         if (!p)
1913                 BUG("when e->type is a delta, it must belong to a pack");
1914
1915         read_lock();
1916         w_curs = NULL;
1917         buf = use_pack(p, &w_curs, e->in_pack_offset, &avail);
1918         used = unpack_object_header_buffer(buf, avail, &type, &size);
1919         if (used == 0)
1920                 die(_("unable to parse object header of %s"),
1921                     oid_to_hex(&e->idx.oid));
1922
1923         unuse_pack(&w_curs);
1924         read_unlock();
1925         return size;
1926 }
1927
1928 static int try_delta(struct unpacked *trg, struct unpacked *src,
1929                      unsigned max_depth, unsigned long *mem_usage)
1930 {
1931         struct object_entry *trg_entry = trg->entry;
1932         struct object_entry *src_entry = src->entry;
1933         unsigned long trg_size, src_size, delta_size, sizediff, max_size, sz;
1934         unsigned ref_depth;
1935         enum object_type type;
1936         void *delta_buf;
1937
1938         /* Don't bother doing diffs between different types */
1939         if (oe_type(trg_entry) != oe_type(src_entry))
1940                 return -1;
1941
1942         /*
1943          * We do not bother to try a delta that we discarded on an
1944          * earlier try, but only when reusing delta data.  Note that
1945          * src_entry that is marked as the preferred_base should always
1946          * be considered, as even if we produce a suboptimal delta against
1947          * it, we will still save the transfer cost, as we already know
1948          * the other side has it and we won't send src_entry at all.
1949          */
1950         if (reuse_delta && IN_PACK(trg_entry) &&
1951             IN_PACK(trg_entry) == IN_PACK(src_entry) &&
1952             !src_entry->preferred_base &&
1953             trg_entry->in_pack_type != OBJ_REF_DELTA &&
1954             trg_entry->in_pack_type != OBJ_OFS_DELTA)
1955                 return 0;
1956
1957         /* Let's not bust the allowed depth. */
1958         if (src->depth >= max_depth)
1959                 return 0;
1960
1961         /* Now some size filtering heuristics. */
1962         trg_size = SIZE(trg_entry);
1963         if (!DELTA(trg_entry)) {
1964                 max_size = trg_size/2 - the_hash_algo->rawsz;
1965                 ref_depth = 1;
1966         } else {
1967                 max_size = DELTA_SIZE(trg_entry);
1968                 ref_depth = trg->depth;
1969         }
1970         max_size = (uint64_t)max_size * (max_depth - src->depth) /
1971                                                 (max_depth - ref_depth + 1);
1972         if (max_size == 0)
1973                 return 0;
1974         src_size = SIZE(src_entry);
1975         sizediff = src_size < trg_size ? trg_size - src_size : 0;
1976         if (sizediff >= max_size)
1977                 return 0;
1978         if (trg_size < src_size / 32)
1979                 return 0;
1980
1981         /* Load data if not already done */
1982         if (!trg->data) {
1983                 read_lock();
1984                 trg->data = read_object_file(&trg_entry->idx.oid, &type, &sz);
1985                 read_unlock();
1986                 if (!trg->data)
1987                         die("object %s cannot be read",
1988                             oid_to_hex(&trg_entry->idx.oid));
1989                 if (sz != trg_size)
1990                         die("object %s inconsistent object length (%lu vs %lu)",
1991                             oid_to_hex(&trg_entry->idx.oid), sz,
1992                             trg_size);
1993                 *mem_usage += sz;
1994         }
1995         if (!src->data) {
1996                 read_lock();
1997                 src->data = read_object_file(&src_entry->idx.oid, &type, &sz);
1998                 read_unlock();
1999                 if (!src->data) {
2000                         if (src_entry->preferred_base) {
2001                                 static int warned = 0;
2002                                 if (!warned++)
2003                                         warning("object %s cannot be read",
2004                                                 oid_to_hex(&src_entry->idx.oid));
2005                                 /*
2006                                  * Those objects are not included in the
2007                                  * resulting pack.  Be resilient and ignore
2008                                  * them if they can't be read, in case the
2009                                  * pack could be created nevertheless.
2010                                  */
2011                                 return 0;
2012                         }
2013                         die("object %s cannot be read",
2014                             oid_to_hex(&src_entry->idx.oid));
2015                 }
2016                 if (sz != src_size)
2017                         die("object %s inconsistent object length (%lu vs %lu)",
2018                             oid_to_hex(&src_entry->idx.oid), sz,
2019                             src_size);
2020                 *mem_usage += sz;
2021         }
2022         if (!src->index) {
2023                 src->index = create_delta_index(src->data, src_size);
2024                 if (!src->index) {
2025                         static int warned = 0;
2026                         if (!warned++)
2027                                 warning("suboptimal pack - out of memory");
2028                         return 0;
2029                 }
2030                 *mem_usage += sizeof_delta_index(src->index);
2031         }
2032
2033         delta_buf = create_delta(src->index, trg->data, trg_size, &delta_size, max_size);
2034         if (!delta_buf)
2035                 return 0;
2036         if (delta_size >= (1U << OE_DELTA_SIZE_BITS)) {
2037                 free(delta_buf);
2038                 return 0;
2039         }
2040
2041         if (DELTA(trg_entry)) {
2042                 /* Prefer only shallower same-sized deltas. */
2043                 if (delta_size == DELTA_SIZE(trg_entry) &&
2044                     src->depth + 1 >= trg->depth) {
2045                         free(delta_buf);
2046                         return 0;
2047                 }
2048         }
2049
2050         /*
2051          * Handle memory allocation outside of the cache
2052          * accounting lock.  Compiler will optimize the strangeness
2053          * away when NO_PTHREADS is defined.
2054          */
2055         free(trg_entry->delta_data);
2056         cache_lock();
2057         if (trg_entry->delta_data) {
2058                 delta_cache_size -= DELTA_SIZE(trg_entry);
2059                 trg_entry->delta_data = NULL;
2060         }
2061         if (delta_cacheable(src_size, trg_size, delta_size)) {
2062                 delta_cache_size += delta_size;
2063                 cache_unlock();
2064                 trg_entry->delta_data = xrealloc(delta_buf, delta_size);
2065         } else {
2066                 cache_unlock();
2067                 free(delta_buf);
2068         }
2069
2070         SET_DELTA(trg_entry, src_entry);
2071         SET_DELTA_SIZE(trg_entry, delta_size);
2072         trg->depth = src->depth + 1;
2073
2074         return 1;
2075 }
2076
2077 static unsigned int check_delta_limit(struct object_entry *me, unsigned int n)
2078 {
2079         struct object_entry *child = DELTA_CHILD(me);
2080         unsigned int m = n;
2081         while (child) {
2082                 unsigned int c = check_delta_limit(child, n + 1);
2083                 if (m < c)
2084                         m = c;
2085                 child = DELTA_SIBLING(child);
2086         }
2087         return m;
2088 }
2089
2090 static unsigned long free_unpacked(struct unpacked *n)
2091 {
2092         unsigned long freed_mem = sizeof_delta_index(n->index);
2093         free_delta_index(n->index);
2094         n->index = NULL;
2095         if (n->data) {
2096                 freed_mem += SIZE(n->entry);
2097                 FREE_AND_NULL(n->data);
2098         }
2099         n->entry = NULL;
2100         n->depth = 0;
2101         return freed_mem;
2102 }
2103
2104 static void find_deltas(struct object_entry **list, unsigned *list_size,
2105                         int window, int depth, unsigned *processed)
2106 {
2107         uint32_t i, idx = 0, count = 0;
2108         struct unpacked *array;
2109         unsigned long mem_usage = 0;
2110
2111         array = xcalloc(window, sizeof(struct unpacked));
2112
2113         for (;;) {
2114                 struct object_entry *entry;
2115                 struct unpacked *n = array + idx;
2116                 int j, max_depth, best_base = -1;
2117
2118                 progress_lock();
2119                 if (!*list_size) {
2120                         progress_unlock();
2121                         break;
2122                 }
2123                 entry = *list++;
2124                 (*list_size)--;
2125                 if (!entry->preferred_base) {
2126                         (*processed)++;
2127                         display_progress(progress_state, *processed);
2128                 }
2129                 progress_unlock();
2130
2131                 mem_usage -= free_unpacked(n);
2132                 n->entry = entry;
2133
2134                 while (window_memory_limit &&
2135                        mem_usage > window_memory_limit &&
2136                        count > 1) {
2137                         uint32_t tail = (idx + window - count) % window;
2138                         mem_usage -= free_unpacked(array + tail);
2139                         count--;
2140                 }
2141
2142                 /* We do not compute delta to *create* objects we are not
2143                  * going to pack.
2144                  */
2145                 if (entry->preferred_base)
2146                         goto next;
2147
2148                 /*
2149                  * If the current object is at pack edge, take the depth the
2150                  * objects that depend on the current object into account
2151                  * otherwise they would become too deep.
2152                  */
2153                 max_depth = depth;
2154                 if (DELTA_CHILD(entry)) {
2155                         max_depth -= check_delta_limit(entry, 0);
2156                         if (max_depth <= 0)
2157                                 goto next;
2158                 }
2159
2160                 j = window;
2161                 while (--j > 0) {
2162                         int ret;
2163                         uint32_t other_idx = idx + j;
2164                         struct unpacked *m;
2165                         if (other_idx >= window)
2166                                 other_idx -= window;
2167                         m = array + other_idx;
2168                         if (!m->entry)
2169                                 break;
2170                         ret = try_delta(n, m, max_depth, &mem_usage);
2171                         if (ret < 0)
2172                                 break;
2173                         else if (ret > 0)
2174                                 best_base = other_idx;
2175                 }
2176
2177                 /*
2178                  * If we decided to cache the delta data, then it is best
2179                  * to compress it right away.  First because we have to do
2180                  * it anyway, and doing it here while we're threaded will
2181                  * save a lot of time in the non threaded write phase,
2182                  * as well as allow for caching more deltas within
2183                  * the same cache size limit.
2184                  * ...
2185                  * But only if not writing to stdout, since in that case
2186                  * the network is most likely throttling writes anyway,
2187                  * and therefore it is best to go to the write phase ASAP
2188                  * instead, as we can afford spending more time compressing
2189                  * between writes at that moment.
2190                  */
2191                 if (entry->delta_data && !pack_to_stdout) {
2192                         unsigned long size;
2193
2194                         size = do_compress(&entry->delta_data, DELTA_SIZE(entry));
2195                         if (size < (1U << OE_Z_DELTA_BITS)) {
2196                                 entry->z_delta_size = size;
2197                                 cache_lock();
2198                                 delta_cache_size -= DELTA_SIZE(entry);
2199                                 delta_cache_size += entry->z_delta_size;
2200                                 cache_unlock();
2201                         } else {
2202                                 FREE_AND_NULL(entry->delta_data);
2203                                 entry->z_delta_size = 0;
2204                         }
2205                 }
2206
2207                 /* if we made n a delta, and if n is already at max
2208                  * depth, leaving it in the window is pointless.  we
2209                  * should evict it first.
2210                  */
2211                 if (DELTA(entry) && max_depth <= n->depth)
2212                         continue;
2213
2214                 /*
2215                  * Move the best delta base up in the window, after the
2216                  * currently deltified object, to keep it longer.  It will
2217                  * be the first base object to be attempted next.
2218                  */
2219                 if (DELTA(entry)) {
2220                         struct unpacked swap = array[best_base];
2221                         int dist = (window + idx - best_base) % window;
2222                         int dst = best_base;
2223                         while (dist--) {
2224                                 int src = (dst + 1) % window;
2225                                 array[dst] = array[src];
2226                                 dst = src;
2227                         }
2228                         array[dst] = swap;
2229                 }
2230
2231                 next:
2232                 idx++;
2233                 if (count + 1 < window)
2234                         count++;
2235                 if (idx >= window)
2236                         idx = 0;
2237         }
2238
2239         for (i = 0; i < window; ++i) {
2240                 free_delta_index(array[i].index);
2241                 free(array[i].data);
2242         }
2243         free(array);
2244 }
2245
2246 #ifndef NO_PTHREADS
2247
2248 static void try_to_free_from_threads(size_t size)
2249 {
2250         read_lock();
2251         release_pack_memory(size);
2252         read_unlock();
2253 }
2254
2255 static try_to_free_t old_try_to_free_routine;
2256
2257 /*
2258  * The main thread waits on the condition that (at least) one of the workers
2259  * has stopped working (which is indicated in the .working member of
2260  * struct thread_params).
2261  * When a work thread has completed its work, it sets .working to 0 and
2262  * signals the main thread and waits on the condition that .data_ready
2263  * becomes 1.
2264  */
2265
2266 struct thread_params {
2267         pthread_t thread;
2268         struct object_entry **list;
2269         unsigned list_size;
2270         unsigned remaining;
2271         int window;
2272         int depth;
2273         int working;
2274         int data_ready;
2275         pthread_mutex_t mutex;
2276         pthread_cond_t cond;
2277         unsigned *processed;
2278 };
2279
2280 static pthread_cond_t progress_cond;
2281
2282 /*
2283  * Mutex and conditional variable can't be statically-initialized on Windows.
2284  */
2285 static void init_threaded_search(void)
2286 {
2287         init_recursive_mutex(&read_mutex);
2288         pthread_mutex_init(&cache_mutex, NULL);
2289         pthread_mutex_init(&progress_mutex, NULL);
2290         pthread_cond_init(&progress_cond, NULL);
2291         old_try_to_free_routine = set_try_to_free_routine(try_to_free_from_threads);
2292 }
2293
2294 static void cleanup_threaded_search(void)
2295 {
2296         set_try_to_free_routine(old_try_to_free_routine);
2297         pthread_cond_destroy(&progress_cond);
2298         pthread_mutex_destroy(&read_mutex);
2299         pthread_mutex_destroy(&cache_mutex);
2300         pthread_mutex_destroy(&progress_mutex);
2301 }
2302
2303 static void *threaded_find_deltas(void *arg)
2304 {
2305         struct thread_params *me = arg;
2306
2307         progress_lock();
2308         while (me->remaining) {
2309                 progress_unlock();
2310
2311                 find_deltas(me->list, &me->remaining,
2312                             me->window, me->depth, me->processed);
2313
2314                 progress_lock();
2315                 me->working = 0;
2316                 pthread_cond_signal(&progress_cond);
2317                 progress_unlock();
2318
2319                 /*
2320                  * We must not set ->data_ready before we wait on the
2321                  * condition because the main thread may have set it to 1
2322                  * before we get here. In order to be sure that new
2323                  * work is available if we see 1 in ->data_ready, it
2324                  * was initialized to 0 before this thread was spawned
2325                  * and we reset it to 0 right away.
2326                  */
2327                 pthread_mutex_lock(&me->mutex);
2328                 while (!me->data_ready)
2329                         pthread_cond_wait(&me->cond, &me->mutex);
2330                 me->data_ready = 0;
2331                 pthread_mutex_unlock(&me->mutex);
2332
2333                 progress_lock();
2334         }
2335         progress_unlock();
2336         /* leave ->working 1 so that this doesn't get more work assigned */
2337         return NULL;
2338 }
2339
2340 static void ll_find_deltas(struct object_entry **list, unsigned list_size,
2341                            int window, int depth, unsigned *processed)
2342 {
2343         struct thread_params *p;
2344         int i, ret, active_threads = 0;
2345
2346         init_threaded_search();
2347
2348         if (delta_search_threads <= 1) {
2349                 find_deltas(list, &list_size, window, depth, processed);
2350                 cleanup_threaded_search();
2351                 return;
2352         }
2353         if (progress > pack_to_stdout)
2354                 fprintf(stderr, "Delta compression using up to %d threads.\n",
2355                                 delta_search_threads);
2356         p = xcalloc(delta_search_threads, sizeof(*p));
2357
2358         /* Partition the work amongst work threads. */
2359         for (i = 0; i < delta_search_threads; i++) {
2360                 unsigned sub_size = list_size / (delta_search_threads - i);
2361
2362                 /* don't use too small segments or no deltas will be found */
2363                 if (sub_size < 2*window && i+1 < delta_search_threads)
2364                         sub_size = 0;
2365
2366                 p[i].window = window;
2367                 p[i].depth = depth;
2368                 p[i].processed = processed;
2369                 p[i].working = 1;
2370                 p[i].data_ready = 0;
2371
2372                 /* try to split chunks on "path" boundaries */
2373                 while (sub_size && sub_size < list_size &&
2374                        list[sub_size]->hash &&
2375                        list[sub_size]->hash == list[sub_size-1]->hash)
2376                         sub_size++;
2377
2378                 p[i].list = list;
2379                 p[i].list_size = sub_size;
2380                 p[i].remaining = sub_size;
2381
2382                 list += sub_size;
2383                 list_size -= sub_size;
2384         }
2385
2386         /* Start work threads. */
2387         for (i = 0; i < delta_search_threads; i++) {
2388                 if (!p[i].list_size)
2389                         continue;
2390                 pthread_mutex_init(&p[i].mutex, NULL);
2391                 pthread_cond_init(&p[i].cond, NULL);
2392                 ret = pthread_create(&p[i].thread, NULL,
2393                                      threaded_find_deltas, &p[i]);
2394                 if (ret)
2395                         die("unable to create thread: %s", strerror(ret));
2396                 active_threads++;
2397         }
2398
2399         /*
2400          * Now let's wait for work completion.  Each time a thread is done
2401          * with its work, we steal half of the remaining work from the
2402          * thread with the largest number of unprocessed objects and give
2403          * it to that newly idle thread.  This ensure good load balancing
2404          * until the remaining object list segments are simply too short
2405          * to be worth splitting anymore.
2406          */
2407         while (active_threads) {
2408                 struct thread_params *target = NULL;
2409                 struct thread_params *victim = NULL;
2410                 unsigned sub_size = 0;
2411
2412                 progress_lock();
2413                 for (;;) {
2414                         for (i = 0; !target && i < delta_search_threads; i++)
2415                                 if (!p[i].working)
2416                                         target = &p[i];
2417                         if (target)
2418                                 break;
2419                         pthread_cond_wait(&progress_cond, &progress_mutex);
2420                 }
2421
2422                 for (i = 0; i < delta_search_threads; i++)
2423                         if (p[i].remaining > 2*window &&
2424                             (!victim || victim->remaining < p[i].remaining))
2425                                 victim = &p[i];
2426                 if (victim) {
2427                         sub_size = victim->remaining / 2;
2428                         list = victim->list + victim->list_size - sub_size;
2429                         while (sub_size && list[0]->hash &&
2430                                list[0]->hash == list[-1]->hash) {
2431                                 list++;
2432                                 sub_size--;
2433                         }
2434                         if (!sub_size) {
2435                                 /*
2436                                  * It is possible for some "paths" to have
2437                                  * so many objects that no hash boundary
2438                                  * might be found.  Let's just steal the
2439                                  * exact half in that case.
2440                                  */
2441                                 sub_size = victim->remaining / 2;
2442                                 list -= sub_size;
2443                         }
2444                         target->list = list;
2445                         victim->list_size -= sub_size;
2446                         victim->remaining -= sub_size;
2447                 }
2448                 target->list_size = sub_size;
2449                 target->remaining = sub_size;
2450                 target->working = 1;
2451                 progress_unlock();
2452
2453                 pthread_mutex_lock(&target->mutex);
2454                 target->data_ready = 1;
2455                 pthread_cond_signal(&target->cond);
2456                 pthread_mutex_unlock(&target->mutex);
2457
2458                 if (!sub_size) {
2459                         pthread_join(target->thread, NULL);
2460                         pthread_cond_destroy(&target->cond);
2461                         pthread_mutex_destroy(&target->mutex);
2462                         active_threads--;
2463                 }
2464         }
2465         cleanup_threaded_search();
2466         free(p);
2467 }
2468
2469 #else
2470 #define ll_find_deltas(l, s, w, d, p)   find_deltas(l, &s, w, d, p)
2471 #endif
2472
2473 static void add_tag_chain(const struct object_id *oid)
2474 {
2475         struct tag *tag;
2476
2477         /*
2478          * We catch duplicates already in add_object_entry(), but we'd
2479          * prefer to do this extra check to avoid having to parse the
2480          * tag at all if we already know that it's being packed (e.g., if
2481          * it was included via bitmaps, we would not have parsed it
2482          * previously).
2483          */
2484         if (packlist_find(&to_pack, oid->hash, NULL))
2485                 return;
2486
2487         tag = lookup_tag(the_repository, oid);
2488         while (1) {
2489                 if (!tag || parse_tag(tag) || !tag->tagged)
2490                         die("unable to pack objects reachable from tag %s",
2491                             oid_to_hex(oid));
2492
2493                 add_object_entry(&tag->object.oid, OBJ_TAG, NULL, 0);
2494
2495                 if (tag->tagged->type != OBJ_TAG)
2496                         return;
2497
2498                 tag = (struct tag *)tag->tagged;
2499         }
2500 }
2501
2502 static int add_ref_tag(const char *path, const struct object_id *oid, int flag, void *cb_data)
2503 {
2504         struct object_id peeled;
2505
2506         if (starts_with(path, "refs/tags/") && /* is a tag? */
2507             !peel_ref(path, &peeled)    && /* peelable? */
2508             packlist_find(&to_pack, peeled.hash, NULL))      /* object packed? */
2509                 add_tag_chain(oid);
2510         return 0;
2511 }
2512
2513 static void prepare_pack(int window, int depth)
2514 {
2515         struct object_entry **delta_list;
2516         uint32_t i, nr_deltas;
2517         unsigned n;
2518
2519         get_object_details();
2520
2521         /*
2522          * If we're locally repacking then we need to be doubly careful
2523          * from now on in order to make sure no stealth corruption gets
2524          * propagated to the new pack.  Clients receiving streamed packs
2525          * should validate everything they get anyway so no need to incur
2526          * the additional cost here in that case.
2527          */
2528         if (!pack_to_stdout)
2529                 do_check_packed_object_crc = 1;
2530
2531         if (!to_pack.nr_objects || !window || !depth)
2532                 return;
2533
2534         ALLOC_ARRAY(delta_list, to_pack.nr_objects);
2535         nr_deltas = n = 0;
2536
2537         for (i = 0; i < to_pack.nr_objects; i++) {
2538                 struct object_entry *entry = to_pack.objects + i;
2539
2540                 if (DELTA(entry))
2541                         /* This happens if we decided to reuse existing
2542                          * delta from a pack.  "reuse_delta &&" is implied.
2543                          */
2544                         continue;
2545
2546                 if (!entry->type_valid ||
2547                     oe_size_less_than(&to_pack, entry, 50))
2548                         continue;
2549
2550                 if (entry->no_try_delta)
2551                         continue;
2552
2553                 if (!entry->preferred_base) {
2554                         nr_deltas++;
2555                         if (oe_type(entry) < 0)
2556                                 die("unable to get type of object %s",
2557                                     oid_to_hex(&entry->idx.oid));
2558                 } else {
2559                         if (oe_type(entry) < 0) {
2560                                 /*
2561                                  * This object is not found, but we
2562                                  * don't have to include it anyway.
2563                                  */
2564                                 continue;
2565                         }
2566                 }
2567
2568                 delta_list[n++] = entry;
2569         }
2570
2571         if (nr_deltas && n > 1) {
2572                 unsigned nr_done = 0;
2573                 if (progress)
2574                         progress_state = start_progress(_("Compressing objects"),
2575                                                         nr_deltas);
2576                 QSORT(delta_list, n, type_size_sort);
2577                 ll_find_deltas(delta_list, n, window+1, depth, &nr_done);
2578                 stop_progress(&progress_state);
2579                 if (nr_done != nr_deltas)
2580                         die("inconsistency with delta count");
2581         }
2582         free(delta_list);
2583 }
2584
2585 static int git_pack_config(const char *k, const char *v, void *cb)
2586 {
2587         if (!strcmp(k, "pack.window")) {
2588                 window = git_config_int(k, v);
2589                 return 0;
2590         }
2591         if (!strcmp(k, "pack.windowmemory")) {
2592                 window_memory_limit = git_config_ulong(k, v);
2593                 return 0;
2594         }
2595         if (!strcmp(k, "pack.depth")) {
2596                 depth = git_config_int(k, v);
2597                 return 0;
2598         }
2599         if (!strcmp(k, "pack.deltacachesize")) {
2600                 max_delta_cache_size = git_config_int(k, v);
2601                 return 0;
2602         }
2603         if (!strcmp(k, "pack.deltacachelimit")) {
2604                 cache_max_small_delta_size = git_config_int(k, v);
2605                 return 0;
2606         }
2607         if (!strcmp(k, "pack.writebitmaphashcache")) {
2608                 if (git_config_bool(k, v))
2609                         write_bitmap_options |= BITMAP_OPT_HASH_CACHE;
2610                 else
2611                         write_bitmap_options &= ~BITMAP_OPT_HASH_CACHE;
2612         }
2613         if (!strcmp(k, "pack.usebitmaps")) {
2614                 use_bitmap_index_default = git_config_bool(k, v);
2615                 return 0;
2616         }
2617         if (!strcmp(k, "pack.threads")) {
2618                 delta_search_threads = git_config_int(k, v);
2619                 if (delta_search_threads < 0)
2620                         die("invalid number of threads specified (%d)",
2621                             delta_search_threads);
2622 #ifdef NO_PTHREADS
2623                 if (delta_search_threads != 1) {
2624                         warning("no threads support, ignoring %s", k);
2625                         delta_search_threads = 0;
2626                 }
2627 #endif
2628                 return 0;
2629         }
2630         if (!strcmp(k, "pack.indexversion")) {
2631                 pack_idx_opts.version = git_config_int(k, v);
2632                 if (pack_idx_opts.version > 2)
2633                         die("bad pack.indexversion=%"PRIu32,
2634                             pack_idx_opts.version);
2635                 return 0;
2636         }
2637         return git_default_config(k, v, cb);
2638 }
2639
2640 static void read_object_list_from_stdin(void)
2641 {
2642         char line[GIT_MAX_HEXSZ + 1 + PATH_MAX + 2];
2643         struct object_id oid;
2644         const char *p;
2645
2646         for (;;) {
2647                 if (!fgets(line, sizeof(line), stdin)) {
2648                         if (feof(stdin))
2649                                 break;
2650                         if (!ferror(stdin))
2651                                 die("fgets returned NULL, not EOF, not error!");
2652                         if (errno != EINTR)
2653                                 die_errno("fgets");
2654                         clearerr(stdin);
2655                         continue;
2656                 }
2657                 if (line[0] == '-') {
2658                         if (get_oid_hex(line+1, &oid))
2659                                 die("expected edge object ID, got garbage:\n %s",
2660                                     line);
2661                         add_preferred_base(&oid);
2662                         continue;
2663                 }
2664                 if (parse_oid_hex(line, &oid, &p))
2665                         die("expected object ID, got garbage:\n %s", line);
2666
2667                 add_preferred_base_object(p + 1);
2668                 add_object_entry(&oid, OBJ_NONE, p + 1, 0);
2669         }
2670 }
2671
2672 /* Remember to update object flag allocation in object.h */
2673 #define OBJECT_ADDED (1u<<20)
2674
2675 static void show_commit(struct commit *commit, void *data)
2676 {
2677         add_object_entry(&commit->object.oid, OBJ_COMMIT, NULL, 0);
2678         commit->object.flags |= OBJECT_ADDED;
2679
2680         if (write_bitmap_index)
2681                 index_commit_for_bitmap(commit);
2682 }
2683
2684 static void show_object(struct object *obj, const char *name, void *data)
2685 {
2686         add_preferred_base_object(name);
2687         add_object_entry(&obj->oid, obj->type, name, 0);
2688         obj->flags |= OBJECT_ADDED;
2689 }
2690
2691 static void show_object__ma_allow_any(struct object *obj, const char *name, void *data)
2692 {
2693         assert(arg_missing_action == MA_ALLOW_ANY);
2694
2695         /*
2696          * Quietly ignore ALL missing objects.  This avoids problems with
2697          * staging them now and getting an odd error later.
2698          */
2699         if (!has_object_file(&obj->oid))
2700                 return;
2701
2702         show_object(obj, name, data);
2703 }
2704
2705 static void show_object__ma_allow_promisor(struct object *obj, const char *name, void *data)
2706 {
2707         assert(arg_missing_action == MA_ALLOW_PROMISOR);
2708
2709         /*
2710          * Quietly ignore EXPECTED missing objects.  This avoids problems with
2711          * staging them now and getting an odd error later.
2712          */
2713         if (!has_object_file(&obj->oid) && is_promisor_object(&obj->oid))
2714                 return;
2715
2716         show_object(obj, name, data);
2717 }
2718
2719 static int option_parse_missing_action(const struct option *opt,
2720                                        const char *arg, int unset)
2721 {
2722         assert(arg);
2723         assert(!unset);
2724
2725         if (!strcmp(arg, "error")) {
2726                 arg_missing_action = MA_ERROR;
2727                 fn_show_object = show_object;
2728                 return 0;
2729         }
2730
2731         if (!strcmp(arg, "allow-any")) {
2732                 arg_missing_action = MA_ALLOW_ANY;
2733                 fetch_if_missing = 0;
2734                 fn_show_object = show_object__ma_allow_any;
2735                 return 0;
2736         }
2737
2738         if (!strcmp(arg, "allow-promisor")) {
2739                 arg_missing_action = MA_ALLOW_PROMISOR;
2740                 fetch_if_missing = 0;
2741                 fn_show_object = show_object__ma_allow_promisor;
2742                 return 0;
2743         }
2744
2745         die(_("invalid value for --missing"));
2746         return 0;
2747 }
2748
2749 static void show_edge(struct commit *commit)
2750 {
2751         add_preferred_base(&commit->object.oid);
2752 }
2753
2754 struct in_pack_object {
2755         off_t offset;
2756         struct object *object;
2757 };
2758
2759 struct in_pack {
2760         unsigned int alloc;
2761         unsigned int nr;
2762         struct in_pack_object *array;
2763 };
2764
2765 static void mark_in_pack_object(struct object *object, struct packed_git *p, struct in_pack *in_pack)
2766 {
2767         in_pack->array[in_pack->nr].offset = find_pack_entry_one(object->oid.hash, p);
2768         in_pack->array[in_pack->nr].object = object;
2769         in_pack->nr++;
2770 }
2771
2772 /*
2773  * Compare the objects in the offset order, in order to emulate the
2774  * "git rev-list --objects" output that produced the pack originally.
2775  */
2776 static int ofscmp(const void *a_, const void *b_)
2777 {
2778         struct in_pack_object *a = (struct in_pack_object *)a_;
2779         struct in_pack_object *b = (struct in_pack_object *)b_;
2780
2781         if (a->offset < b->offset)
2782                 return -1;
2783         else if (a->offset > b->offset)
2784                 return 1;
2785         else
2786                 return oidcmp(&a->object->oid, &b->object->oid);
2787 }
2788
2789 static void add_objects_in_unpacked_packs(struct rev_info *revs)
2790 {
2791         struct packed_git *p;
2792         struct in_pack in_pack;
2793         uint32_t i;
2794
2795         memset(&in_pack, 0, sizeof(in_pack));
2796
2797         for (p = get_packed_git(the_repository); p; p = p->next) {
2798                 struct object_id oid;
2799                 struct object *o;
2800
2801                 if (!p->pack_local || p->pack_keep || p->pack_keep_in_core)
2802                         continue;
2803                 if (open_pack_index(p))
2804                         die("cannot open pack index");
2805
2806                 ALLOC_GROW(in_pack.array,
2807                            in_pack.nr + p->num_objects,
2808                            in_pack.alloc);
2809
2810                 for (i = 0; i < p->num_objects; i++) {
2811                         nth_packed_object_oid(&oid, p, i);
2812                         o = lookup_unknown_object(oid.hash);
2813                         if (!(o->flags & OBJECT_ADDED))
2814                                 mark_in_pack_object(o, p, &in_pack);
2815                         o->flags |= OBJECT_ADDED;
2816                 }
2817         }
2818
2819         if (in_pack.nr) {
2820                 QSORT(in_pack.array, in_pack.nr, ofscmp);
2821                 for (i = 0; i < in_pack.nr; i++) {
2822                         struct object *o = in_pack.array[i].object;
2823                         add_object_entry(&o->oid, o->type, "", 0);
2824                 }
2825         }
2826         free(in_pack.array);
2827 }
2828
2829 static int add_loose_object(const struct object_id *oid, const char *path,
2830                             void *data)
2831 {
2832         enum object_type type = oid_object_info(the_repository, oid, NULL);
2833
2834         if (type < 0) {
2835                 warning("loose object at %s could not be examined", path);
2836                 return 0;
2837         }
2838
2839         add_object_entry(oid, type, "", 0);
2840         return 0;
2841 }
2842
2843 /*
2844  * We actually don't even have to worry about reachability here.
2845  * add_object_entry will weed out duplicates, so we just add every
2846  * loose object we find.
2847  */
2848 static void add_unreachable_loose_objects(void)
2849 {
2850         for_each_loose_file_in_objdir(get_object_directory(),
2851                                       add_loose_object,
2852                                       NULL, NULL, NULL);
2853 }
2854
2855 static int has_sha1_pack_kept_or_nonlocal(const struct object_id *oid)
2856 {
2857         static struct packed_git *last_found = (void *)1;
2858         struct packed_git *p;
2859
2860         p = (last_found != (void *)1) ? last_found :
2861                                         get_packed_git(the_repository);
2862
2863         while (p) {
2864                 if ((!p->pack_local || p->pack_keep ||
2865                                 p->pack_keep_in_core) &&
2866                         find_pack_entry_one(oid->hash, p)) {
2867                         last_found = p;
2868                         return 1;
2869                 }
2870                 if (p == last_found)
2871                         p = get_packed_git(the_repository);
2872                 else
2873                         p = p->next;
2874                 if (p == last_found)
2875                         p = p->next;
2876         }
2877         return 0;
2878 }
2879
2880 /*
2881  * Store a list of sha1s that are should not be discarded
2882  * because they are either written too recently, or are
2883  * reachable from another object that was.
2884  *
2885  * This is filled by get_object_list.
2886  */
2887 static struct oid_array recent_objects;
2888
2889 static int loosened_object_can_be_discarded(const struct object_id *oid,
2890                                             timestamp_t mtime)
2891 {
2892         if (!unpack_unreachable_expiration)
2893                 return 0;
2894         if (mtime > unpack_unreachable_expiration)
2895                 return 0;
2896         if (oid_array_lookup(&recent_objects, oid) >= 0)
2897                 return 0;
2898         return 1;
2899 }
2900
2901 static void loosen_unused_packed_objects(struct rev_info *revs)
2902 {
2903         struct packed_git *p;
2904         uint32_t i;
2905         struct object_id oid;
2906
2907         for (p = get_packed_git(the_repository); p; p = p->next) {
2908                 if (!p->pack_local || p->pack_keep || p->pack_keep_in_core)
2909                         continue;
2910
2911                 if (open_pack_index(p))
2912                         die("cannot open pack index");
2913
2914                 for (i = 0; i < p->num_objects; i++) {
2915                         nth_packed_object_oid(&oid, p, i);
2916                         if (!packlist_find(&to_pack, oid.hash, NULL) &&
2917                             !has_sha1_pack_kept_or_nonlocal(&oid) &&
2918                             !loosened_object_can_be_discarded(&oid, p->mtime))
2919                                 if (force_object_loose(&oid, p->mtime))
2920                                         die("unable to force loose object");
2921                 }
2922         }
2923 }
2924
2925 /*
2926  * This tracks any options which pack-reuse code expects to be on, or which a
2927  * reader of the pack might not understand, and which would therefore prevent
2928  * blind reuse of what we have on disk.
2929  */
2930 static int pack_options_allow_reuse(void)
2931 {
2932         return pack_to_stdout &&
2933                allow_ofs_delta &&
2934                !ignore_packed_keep_on_disk &&
2935                !ignore_packed_keep_in_core &&
2936                (!local || !have_non_local_packs) &&
2937                !incremental;
2938 }
2939
2940 static int get_object_list_from_bitmap(struct rev_info *revs)
2941 {
2942         struct bitmap_index *bitmap_git;
2943         if (!(bitmap_git = prepare_bitmap_walk(revs)))
2944                 return -1;
2945
2946         if (pack_options_allow_reuse() &&
2947             !reuse_partial_packfile_from_bitmap(
2948                         bitmap_git,
2949                         &reuse_packfile,
2950                         &reuse_packfile_objects,
2951                         &reuse_packfile_offset)) {
2952                 assert(reuse_packfile_objects);
2953                 nr_result += reuse_packfile_objects;
2954                 display_progress(progress_state, nr_result);
2955         }
2956
2957         traverse_bitmap_commit_list(bitmap_git, &add_object_entry_from_bitmap);
2958         free_bitmap_index(bitmap_git);
2959         return 0;
2960 }
2961
2962 static void record_recent_object(struct object *obj,
2963                                  const char *name,
2964                                  void *data)
2965 {
2966         oid_array_append(&recent_objects, &obj->oid);
2967 }
2968
2969 static void record_recent_commit(struct commit *commit, void *data)
2970 {
2971         oid_array_append(&recent_objects, &commit->object.oid);
2972 }
2973
2974 static void get_object_list(int ac, const char **av)
2975 {
2976         struct rev_info revs;
2977         char line[1000];
2978         int flags = 0;
2979
2980         init_revisions(&revs, NULL);
2981         save_commit_buffer = 0;
2982         setup_revisions(ac, av, &revs, NULL);
2983
2984         /* make sure shallows are read */
2985         is_repository_shallow(the_repository);
2986
2987         while (fgets(line, sizeof(line), stdin) != NULL) {
2988                 int len = strlen(line);
2989                 if (len && line[len - 1] == '\n')
2990                         line[--len] = 0;
2991                 if (!len)
2992                         break;
2993                 if (*line == '-') {
2994                         if (!strcmp(line, "--not")) {
2995                                 flags ^= UNINTERESTING;
2996                                 write_bitmap_index = 0;
2997                                 continue;
2998                         }
2999                         if (starts_with(line, "--shallow ")) {
3000                                 struct object_id oid;
3001                                 if (get_oid_hex(line + 10, &oid))
3002                                         die("not an SHA-1 '%s'", line + 10);
3003                                 register_shallow(the_repository, &oid);
3004                                 use_bitmap_index = 0;
3005                                 continue;
3006                         }
3007                         die("not a rev '%s'", line);
3008                 }
3009                 if (handle_revision_arg(line, &revs, flags, REVARG_CANNOT_BE_FILENAME))
3010                         die("bad revision '%s'", line);
3011         }
3012
3013         if (use_bitmap_index && !get_object_list_from_bitmap(&revs))
3014                 return;
3015
3016         if (prepare_revision_walk(&revs))
3017                 die("revision walk setup failed");
3018         mark_edges_uninteresting(&revs, show_edge);
3019
3020         if (!fn_show_object)
3021                 fn_show_object = show_object;
3022         traverse_commit_list_filtered(&filter_options, &revs,
3023                                       show_commit, fn_show_object, NULL,
3024                                       NULL);
3025
3026         if (unpack_unreachable_expiration) {
3027                 revs.ignore_missing_links = 1;
3028                 if (add_unseen_recent_objects_to_traversal(&revs,
3029                                 unpack_unreachable_expiration))
3030                         die("unable to add recent objects");
3031                 if (prepare_revision_walk(&revs))
3032                         die("revision walk setup failed");
3033                 traverse_commit_list(&revs, record_recent_commit,
3034                                      record_recent_object, NULL);
3035         }
3036
3037         if (keep_unreachable)
3038                 add_objects_in_unpacked_packs(&revs);
3039         if (pack_loose_unreachable)
3040                 add_unreachable_loose_objects();
3041         if (unpack_unreachable)
3042                 loosen_unused_packed_objects(&revs);
3043
3044         oid_array_clear(&recent_objects);
3045 }
3046
3047 static void add_extra_kept_packs(const struct string_list *names)
3048 {
3049         struct packed_git *p;
3050
3051         if (!names->nr)
3052                 return;
3053
3054         for (p = get_packed_git(the_repository); p; p = p->next) {
3055                 const char *name = basename(p->pack_name);
3056                 int i;
3057
3058                 if (!p->pack_local)
3059                         continue;
3060
3061                 for (i = 0; i < names->nr; i++)
3062                         if (!fspathcmp(name, names->items[i].string))
3063                                 break;
3064
3065                 if (i < names->nr) {
3066                         p->pack_keep_in_core = 1;
3067                         ignore_packed_keep_in_core = 1;
3068                         continue;
3069                 }
3070         }
3071 }
3072
3073 static int option_parse_index_version(const struct option *opt,
3074                                       const char *arg, int unset)
3075 {
3076         char *c;
3077         const char *val = arg;
3078         pack_idx_opts.version = strtoul(val, &c, 10);
3079         if (pack_idx_opts.version > 2)
3080                 die(_("unsupported index version %s"), val);
3081         if (*c == ',' && c[1])
3082                 pack_idx_opts.off32_limit = strtoul(c+1, &c, 0);
3083         if (*c || pack_idx_opts.off32_limit & 0x80000000)
3084                 die(_("bad index version '%s'"), val);
3085         return 0;
3086 }
3087
3088 static int option_parse_unpack_unreachable(const struct option *opt,
3089                                            const char *arg, int unset)
3090 {
3091         if (unset) {
3092                 unpack_unreachable = 0;
3093                 unpack_unreachable_expiration = 0;
3094         }
3095         else {
3096                 unpack_unreachable = 1;
3097                 if (arg)
3098                         unpack_unreachable_expiration = approxidate(arg);
3099         }
3100         return 0;
3101 }
3102
3103 int cmd_pack_objects(int argc, const char **argv, const char *prefix)
3104 {
3105         int use_internal_rev_list = 0;
3106         int thin = 0;
3107         int shallow = 0;
3108         int all_progress_implied = 0;
3109         struct argv_array rp = ARGV_ARRAY_INIT;
3110         int rev_list_unpacked = 0, rev_list_all = 0, rev_list_reflog = 0;
3111         int rev_list_index = 0;
3112         struct string_list keep_pack_list = STRING_LIST_INIT_NODUP;
3113         struct option pack_objects_options[] = {
3114                 OPT_SET_INT('q', "quiet", &progress,
3115                             N_("do not show progress meter"), 0),
3116                 OPT_SET_INT(0, "progress", &progress,
3117                             N_("show progress meter"), 1),
3118                 OPT_SET_INT(0, "all-progress", &progress,
3119                             N_("show progress meter during object writing phase"), 2),
3120                 OPT_BOOL(0, "all-progress-implied",
3121                          &all_progress_implied,
3122                          N_("similar to --all-progress when progress meter is shown")),
3123                 { OPTION_CALLBACK, 0, "index-version", NULL, N_("version[,offset]"),
3124                   N_("write the pack index file in the specified idx format version"),
3125                   0, option_parse_index_version },
3126                 OPT_MAGNITUDE(0, "max-pack-size", &pack_size_limit,
3127                               N_("maximum size of each output pack file")),
3128                 OPT_BOOL(0, "local", &local,
3129                          N_("ignore borrowed objects from alternate object store")),
3130                 OPT_BOOL(0, "incremental", &incremental,
3131                          N_("ignore packed objects")),
3132                 OPT_INTEGER(0, "window", &window,
3133                             N_("limit pack window by objects")),
3134                 OPT_MAGNITUDE(0, "window-memory", &window_memory_limit,
3135                               N_("limit pack window by memory in addition to object limit")),
3136                 OPT_INTEGER(0, "depth", &depth,
3137                             N_("maximum length of delta chain allowed in the resulting pack")),
3138                 OPT_BOOL(0, "reuse-delta", &reuse_delta,
3139                          N_("reuse existing deltas")),
3140                 OPT_BOOL(0, "reuse-object", &reuse_object,
3141                          N_("reuse existing objects")),
3142                 OPT_BOOL(0, "delta-base-offset", &allow_ofs_delta,
3143                          N_("use OFS_DELTA objects")),
3144                 OPT_INTEGER(0, "threads", &delta_search_threads,
3145                             N_("use threads when searching for best delta matches")),
3146                 OPT_BOOL(0, "non-empty", &non_empty,
3147                          N_("do not create an empty pack output")),
3148                 OPT_BOOL(0, "revs", &use_internal_rev_list,
3149                          N_("read revision arguments from standard input")),
3150                 OPT_SET_INT_F(0, "unpacked", &rev_list_unpacked,
3151                               N_("limit the objects to those that are not yet packed"),
3152                               1, PARSE_OPT_NONEG),
3153                 OPT_SET_INT_F(0, "all", &rev_list_all,
3154                               N_("include objects reachable from any reference"),
3155                               1, PARSE_OPT_NONEG),
3156                 OPT_SET_INT_F(0, "reflog", &rev_list_reflog,
3157                               N_("include objects referred by reflog entries"),
3158                               1, PARSE_OPT_NONEG),
3159                 OPT_SET_INT_F(0, "indexed-objects", &rev_list_index,
3160                               N_("include objects referred to by the index"),
3161                               1, PARSE_OPT_NONEG),
3162                 OPT_BOOL(0, "stdout", &pack_to_stdout,
3163                          N_("output pack to stdout")),
3164                 OPT_BOOL(0, "include-tag", &include_tag,
3165                          N_("include tag objects that refer to objects to be packed")),
3166                 OPT_BOOL(0, "keep-unreachable", &keep_unreachable,
3167                          N_("keep unreachable objects")),
3168                 OPT_BOOL(0, "pack-loose-unreachable", &pack_loose_unreachable,
3169                          N_("pack loose unreachable objects")),
3170                 { OPTION_CALLBACK, 0, "unpack-unreachable", NULL, N_("time"),
3171                   N_("unpack unreachable objects newer than <time>"),
3172                   PARSE_OPT_OPTARG, option_parse_unpack_unreachable },
3173                 OPT_BOOL(0, "thin", &thin,
3174                          N_("create thin packs")),
3175                 OPT_BOOL(0, "shallow", &shallow,
3176                          N_("create packs suitable for shallow fetches")),
3177                 OPT_BOOL(0, "honor-pack-keep", &ignore_packed_keep_on_disk,
3178                          N_("ignore packs that have companion .keep file")),
3179                 OPT_STRING_LIST(0, "keep-pack", &keep_pack_list, N_("name"),
3180                                 N_("ignore this pack")),
3181                 OPT_INTEGER(0, "compression", &pack_compression_level,
3182                             N_("pack compression level")),
3183                 OPT_SET_INT(0, "keep-true-parents", &grafts_replace_parents,
3184                             N_("do not hide commits by grafts"), 0),
3185                 OPT_BOOL(0, "use-bitmap-index", &use_bitmap_index,
3186                          N_("use a bitmap index if available to speed up counting objects")),
3187                 OPT_BOOL(0, "write-bitmap-index", &write_bitmap_index,
3188                          N_("write a bitmap index together with the pack index")),
3189                 OPT_PARSE_LIST_OBJECTS_FILTER(&filter_options),
3190                 { OPTION_CALLBACK, 0, "missing", NULL, N_("action"),
3191                   N_("handling for missing objects"), PARSE_OPT_NONEG,
3192                   option_parse_missing_action },
3193                 OPT_BOOL(0, "exclude-promisor-objects", &exclude_promisor_objects,
3194                          N_("do not pack objects in promisor packfiles")),
3195                 OPT_END(),
3196         };
3197
3198         if (DFS_NUM_STATES > (1 << OE_DFS_STATE_BITS))
3199                 BUG("too many dfs states, increase OE_DFS_STATE_BITS");
3200
3201         check_replace_refs = 0;
3202
3203         reset_pack_idx_option(&pack_idx_opts);
3204         git_config(git_pack_config, NULL);
3205
3206         progress = isatty(2);
3207         argc = parse_options(argc, argv, prefix, pack_objects_options,
3208                              pack_usage, 0);
3209
3210         if (argc) {
3211                 base_name = argv[0];
3212                 argc--;
3213         }
3214         if (pack_to_stdout != !base_name || argc)
3215                 usage_with_options(pack_usage, pack_objects_options);
3216
3217         if (depth >= (1 << OE_DEPTH_BITS)) {
3218                 warning(_("delta chain depth %d is too deep, forcing %d"),
3219                         depth, (1 << OE_DEPTH_BITS) - 1);
3220                 depth = (1 << OE_DEPTH_BITS) - 1;
3221         }
3222         if (cache_max_small_delta_size >= (1U << OE_Z_DELTA_BITS)) {
3223                 warning(_("pack.deltaCacheLimit is too high, forcing %d"),
3224                         (1U << OE_Z_DELTA_BITS) - 1);
3225                 cache_max_small_delta_size = (1U << OE_Z_DELTA_BITS) - 1;
3226         }
3227
3228         argv_array_push(&rp, "pack-objects");
3229         if (thin) {
3230                 use_internal_rev_list = 1;
3231                 argv_array_push(&rp, shallow
3232                                 ? "--objects-edge-aggressive"
3233                                 : "--objects-edge");
3234         } else
3235                 argv_array_push(&rp, "--objects");
3236
3237         if (rev_list_all) {
3238                 use_internal_rev_list = 1;
3239                 argv_array_push(&rp, "--all");
3240         }
3241         if (rev_list_reflog) {
3242                 use_internal_rev_list = 1;
3243                 argv_array_push(&rp, "--reflog");
3244         }
3245         if (rev_list_index) {
3246                 use_internal_rev_list = 1;
3247                 argv_array_push(&rp, "--indexed-objects");
3248         }
3249         if (rev_list_unpacked) {
3250                 use_internal_rev_list = 1;
3251                 argv_array_push(&rp, "--unpacked");
3252         }
3253
3254         if (exclude_promisor_objects) {
3255                 use_internal_rev_list = 1;
3256                 fetch_if_missing = 0;
3257                 argv_array_push(&rp, "--exclude-promisor-objects");
3258         }
3259         if (unpack_unreachable || keep_unreachable || pack_loose_unreachable)
3260                 use_internal_rev_list = 1;
3261
3262         if (!reuse_object)
3263                 reuse_delta = 0;
3264         if (pack_compression_level == -1)
3265                 pack_compression_level = Z_DEFAULT_COMPRESSION;
3266         else if (pack_compression_level < 0 || pack_compression_level > Z_BEST_COMPRESSION)
3267                 die("bad pack compression level %d", pack_compression_level);
3268
3269         if (!delta_search_threads)      /* --threads=0 means autodetect */
3270                 delta_search_threads = online_cpus();
3271
3272 #ifdef NO_PTHREADS
3273         if (delta_search_threads != 1)
3274                 warning("no threads support, ignoring --threads");
3275 #endif
3276         if (!pack_to_stdout && !pack_size_limit)
3277                 pack_size_limit = pack_size_limit_cfg;
3278         if (pack_to_stdout && pack_size_limit)
3279                 die("--max-pack-size cannot be used to build a pack for transfer.");
3280         if (pack_size_limit && pack_size_limit < 1024*1024) {
3281                 warning("minimum pack size limit is 1 MiB");
3282                 pack_size_limit = 1024*1024;
3283         }
3284
3285         if (!pack_to_stdout && thin)
3286                 die("--thin cannot be used to build an indexable pack.");
3287
3288         if (keep_unreachable && unpack_unreachable)
3289                 die("--keep-unreachable and --unpack-unreachable are incompatible.");
3290         if (!rev_list_all || !rev_list_reflog || !rev_list_index)
3291                 unpack_unreachable_expiration = 0;
3292
3293         if (filter_options.choice) {
3294                 if (!pack_to_stdout)
3295                         die("cannot use --filter without --stdout.");
3296                 use_bitmap_index = 0;
3297         }
3298
3299         /*
3300          * "soft" reasons not to use bitmaps - for on-disk repack by default we want
3301          *
3302          * - to produce good pack (with bitmap index not-yet-packed objects are
3303          *   packed in suboptimal order).
3304          *
3305          * - to use more robust pack-generation codepath (avoiding possible
3306          *   bugs in bitmap code and possible bitmap index corruption).
3307          */
3308         if (!pack_to_stdout)
3309                 use_bitmap_index_default = 0;
3310
3311         if (use_bitmap_index < 0)
3312                 use_bitmap_index = use_bitmap_index_default;
3313
3314         /* "hard" reasons not to use bitmaps; these just won't work at all */
3315         if (!use_internal_rev_list || (!pack_to_stdout && write_bitmap_index) || is_repository_shallow(the_repository))
3316                 use_bitmap_index = 0;
3317
3318         if (pack_to_stdout || !rev_list_all)
3319                 write_bitmap_index = 0;
3320
3321         if (progress && all_progress_implied)
3322                 progress = 2;
3323
3324         add_extra_kept_packs(&keep_pack_list);
3325         if (ignore_packed_keep_on_disk) {
3326                 struct packed_git *p;
3327                 for (p = get_packed_git(the_repository); p; p = p->next)
3328                         if (p->pack_local && p->pack_keep)
3329                                 break;
3330                 if (!p) /* no keep-able packs found */
3331                         ignore_packed_keep_on_disk = 0;
3332         }
3333         if (local) {
3334                 /*
3335                  * unlike ignore_packed_keep_on_disk above, we do not
3336                  * want to unset "local" based on looking at packs, as
3337                  * it also covers non-local objects
3338                  */
3339                 struct packed_git *p;
3340                 for (p = get_packed_git(the_repository); p; p = p->next) {
3341                         if (!p->pack_local) {
3342                                 have_non_local_packs = 1;
3343                                 break;
3344                         }
3345                 }
3346         }
3347
3348         prepare_packing_data(&to_pack);
3349
3350         if (progress)
3351                 progress_state = start_progress(_("Enumerating objects"), 0);
3352         if (!use_internal_rev_list)
3353                 read_object_list_from_stdin();
3354         else {
3355                 get_object_list(rp.argc, rp.argv);
3356                 argv_array_clear(&rp);
3357         }
3358         cleanup_preferred_base();
3359         if (include_tag && nr_result)
3360                 for_each_ref(add_ref_tag, NULL);
3361         stop_progress(&progress_state);
3362
3363         if (non_empty && !nr_result)
3364                 return 0;
3365         if (nr_result)
3366                 prepare_pack(window, depth);
3367         write_pack_file();
3368         if (progress)
3369                 fprintf(stderr, "Total %"PRIu32" (delta %"PRIu32"),"
3370                         " reused %"PRIu32" (delta %"PRIu32")\n",
3371                         written, written_delta, reused, reused_delta);
3372         return 0;
3373 }