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

   1 #include "builtin.h"
   2 #include "cache.h"
   3 #include "object.h"
   4 #include "blob.h"
   5 #include "commit.h"
   6 #include "tag.h"
   7 #include "tree.h"
   8 #include "delta.h"
   9 #include "pack.h"
  10 #include "csum-file.h"
  11 #include "tree-walk.h"
  12 #include "diff.h"
  13 #include "revision.h"
  14 #include "list-objects.h"
  15 #include <sys/time.h>
  16 #include <signal.h>
  17
  18 static const char pack_usage[] = "git-pack-objects [-q] [--no-reuse-delta] [--non-empty] [--local] [--incremental] [--window=N] [--depth=N] [--revs [--unpacked | --all]*] [--stdout | base-name] <ref-list | <object-list]";
  19
  20 struct object_entry {
  21         unsigned char sha1[20];
  22         unsigned long size;     /* uncompressed size */
  23         unsigned long offset;   /* offset into the final pack file;
  24                                  * nonzero if already written.
  25                                  */
  26         unsigned int depth;     /* delta depth */
  27         unsigned int delta_limit;       /* base adjustment for in-pack delta */
  28         unsigned int hash;      /* name hint hash */
  29         enum object_type type;
  30         enum object_type in_pack_type;  /* could be delta */
  31         unsigned long delta_size;       /* delta data size (uncompressed) */
  32 #define in_pack_header_size delta_size  /* only when reusing pack data */
  33         struct object_entry *delta;     /* delta base object */
  34         struct packed_git *in_pack;     /* already in pack */
  35         unsigned int in_pack_offset;
  36         struct object_entry *delta_child; /* deltified objects who bases me */
  37         struct object_entry *delta_sibling; /* other deltified objects who
  38                                              * uses the same base as me
  39                                              */
  40         int preferred_base;     /* we do not pack this, but is encouraged to
  41                                  * be used as the base objectto delta huge
  42                                  * objects against.
  43                                  */
  44 };
  45
  46 /*
  47  * Objects we are going to pack are collected in objects array (dynamically
  48  * expanded).  nr_objects & nr_alloc controls this array.  They are stored
  49  * in the order we see -- typically rev-list --objects order that gives us
  50  * nice "minimum seek" order.
  51  *
  52  * sorted-by-sha ans sorted-by-type are arrays of pointers that point at
  53  * elements in the objects array.  The former is used to build the pack
  54  * index (lists object names in the ascending order to help offset lookup),
  55  * and the latter is used to group similar things together by try_delta()
  56  * heuristics.
  57  */
  58
  59 static unsigned char object_list_sha1[20];
  60 static int non_empty;
  61 static int no_reuse_delta;
  62 static int local;
  63 static int incremental;
  64 static int allow_ofs_delta;
  65
  66 static struct object_entry **sorted_by_sha, **sorted_by_type;
  67 static struct object_entry *objects;
  68 static int nr_objects, nr_alloc, nr_result;
  69 static const char *base_name;
  70 static unsigned char pack_file_sha1[20];
  71 static int progress = 1;
  72 static volatile sig_atomic_t progress_update;
  73 static int window = 10;
  74 static int pack_to_stdout;
  75 static int num_preferred_base;
  76
  77 /*
  78  * The object names in objects array are hashed with this hashtable,
  79  * to help looking up the entry by object name.  Binary search from
  80  * sorted_by_sha is also possible but this was easier to code and faster.
  81  * This hashtable is built after all the objects are seen.
  82  */
  83 static int *object_ix;
  84 static int object_ix_hashsz;
  85
  86 /*
  87  * Pack index for existing packs give us easy access to the offsets into
  88  * corresponding pack file where each object's data starts, but the entries
  89  * do not store the size of the compressed representation (uncompressed
  90  * size is easily available by examining the pack entry header).  It is
  91  * also rather expensive to find the sha1 for an object given its offset.
  92  *
  93  * We build a hashtable of existing packs (pack_revindex), and keep reverse
  94  * index here -- pack index file is sorted by object name mapping to offset;
  95  * this pack_revindex[].revindex array is a list of offset/index_nr pairs
  96  * ordered by offset, so if you know the offset of an object, next offset
  97  * is where its packed representation ends and the index_nr can be used to
  98  * get the object sha1 from the main index.
  99  */
 100 struct revindex_entry {
 101         unsigned int offset;
 102         unsigned int nr;
 103 };
 104 struct pack_revindex {
 105         struct packed_git *p;
 106         struct revindex_entry *revindex;
 107 };
 108 static struct  pack_revindex *pack_revindex;
 109 static int pack_revindex_hashsz;
 110
 111 /*
 112  * stats
 113  */
 114 static int written;
 115 static int written_delta;
 116 static int reused;
 117 static int reused_delta;
 118
 119 static int pack_revindex_ix(struct packed_git *p)
 120 {
 121         unsigned long ui = (unsigned long)p;
 122         int i;
 123
 124         ui = ui ^ (ui >> 16); /* defeat structure alignment */
 125         i = (int)(ui % pack_revindex_hashsz);
 126         while (pack_revindex[i].p) {
 127                 if (pack_revindex[i].p == p)
 128                         return i;
 129                 if (++i == pack_revindex_hashsz)
 130                         i = 0;
 131         }
 132         return -1 - i;
 133 }
 134
 135 static void prepare_pack_ix(void)
 136 {
 137         int num;
 138         struct packed_git *p;
 139         for (num = 0, p = packed_git; p; p = p->next)
 140                 num++;
 141         if (!num)
 142                 return;
 143         pack_revindex_hashsz = num * 11;
 144         pack_revindex = xcalloc(sizeof(*pack_revindex), pack_revindex_hashsz);
 145         for (p = packed_git; p; p = p->next) {
 146                 num = pack_revindex_ix(p);
 147                 num = - 1 - num;
 148                 pack_revindex[num].p = p;
 149         }
 150         /* revindex elements are lazily initialized */
 151 }
 152
 153 static int cmp_offset(const void *a_, const void *b_)
 154 {
 155         const struct revindex_entry *a = a_;
 156         const struct revindex_entry *b = b_;
 157         return (a->offset < b->offset) ? -1 : (a->offset > b->offset) ? 1 : 0;
 158 }
 159
 160 /*
 161  * Ordered list of offsets of objects in the pack.
 162  */
 163 static void prepare_pack_revindex(struct pack_revindex *rix)
 164 {
 165         struct packed_git *p = rix->p;
 166         int num_ent = num_packed_objects(p);
 167         int i;
 168         void *index = p->index_base + 256;
 169
 170         rix->revindex = xmalloc(sizeof(*rix->revindex) * (num_ent + 1));
 171         for (i = 0; i < num_ent; i++) {
 172                 unsigned int hl = *((unsigned int *)((char *) index + 24*i));
 173                 rix->revindex[i].offset = ntohl(hl);
 174                 rix->revindex[i].nr = i;
 175         }
 176         /* This knows the pack format -- the 20-byte trailer
 177          * follows immediately after the last object data.
 178          */
 179         rix->revindex[num_ent].offset = p->pack_size - 20;
 180         rix->revindex[num_ent].nr = -1;
 181         qsort(rix->revindex, num_ent, sizeof(*rix->revindex), cmp_offset);
 182 }
 183
 184 static struct revindex_entry * find_packed_object(struct packed_git *p,
 185                                                   unsigned int ofs)
 186 {
 187         int num;
 188         int lo, hi;
 189         struct pack_revindex *rix;
 190         struct revindex_entry *revindex;
 191         num = pack_revindex_ix(p);
 192         if (num < 0)
 193                 die("internal error: pack revindex uninitialized");
 194         rix = &pack_revindex[num];
 195         if (!rix->revindex)
 196                 prepare_pack_revindex(rix);
 197         revindex = rix->revindex;
 198         lo = 0;
 199         hi = num_packed_objects(p) + 1;
 200         do {
 201                 int mi = (lo + hi) / 2;
 202                 if (revindex[mi].offset == ofs) {
 203                         return revindex + mi;
 204                 }
 205                 else if (ofs < revindex[mi].offset)
 206                         hi = mi;
 207                 else
 208                         lo = mi + 1;
 209         } while (lo < hi);
 210         die("internal error: pack revindex corrupt");
 211 }
 212
 213 static unsigned long find_packed_object_size(struct packed_git *p,
 214                                              unsigned long ofs)
 215 {
 216         struct revindex_entry *entry = find_packed_object(p, ofs);
 217         return entry[1].offset - ofs;
 218 }
 219
 220 static unsigned char *find_packed_object_name(struct packed_git *p,
 221                                               unsigned long ofs)
 222 {
 223         struct revindex_entry *entry = find_packed_object(p, ofs);
 224         return (unsigned char *)(p->index_base + 256) + 24 * entry->nr + 4;
 225 }
 226
 227 static void *delta_against(void *buf, unsigned long size, struct object_entry *entry)
 228 {
 229         unsigned long othersize, delta_size;
 230         char type[10];
 231         void *otherbuf = read_sha1_file(entry->delta->sha1, type, &othersize);
 232         void *delta_buf;
 233
 234         if (!otherbuf)
 235                 die("unable to read %s", sha1_to_hex(entry->delta->sha1));
 236         delta_buf = diff_delta(otherbuf, othersize,
 237                                buf, size, &delta_size, 0);
 238         if (!delta_buf || delta_size != entry->delta_size)
 239                 die("delta size changed");
 240         free(buf);
 241         free(otherbuf);
 242         return delta_buf;
 243 }
 244
 245 /*
 246  * The per-object header is a pretty dense thing, which is
 247  *  - first byte: low four bits are "size", then three bits of "type",
 248  *    and the high bit is "size continues".
 249  *  - each byte afterwards: low seven bits are size continuation,
 250  *    with the high bit being "size continues"
 251  */
 252 static int encode_header(enum object_type type, unsigned long size, unsigned char *hdr)
 253 {
 254         int n = 1;
 255         unsigned char c;
 256
 257         if (type < OBJ_COMMIT || type > OBJ_REF_DELTA)
 258                 die("bad type %d", type);
 259
 260         c = (type << 4) | (size & 15);
 261         size >>= 4;
 262         while (size) {
 263                 *hdr++ = c | 0x80;
 264                 c = size & 0x7f;
 265                 size >>= 7;
 266                 n++;
 267         }
 268         *hdr = c;
 269         return n;
 270 }
 271
 272 /*
 273  * we are going to reuse the existing object data as is.  make
 274  * sure it is not corrupt.
 275  */
 276 static int check_inflate(unsigned char *data, unsigned long len, unsigned long expect)
 277 {
 278         z_stream stream;
 279         unsigned char fakebuf[4096];
 280         int st;
 281
 282         memset(&stream, 0, sizeof(stream));
 283         stream.next_in = data;
 284         stream.avail_in = len;
 285         stream.next_out = fakebuf;
 286         stream.avail_out = sizeof(fakebuf);
 287         inflateInit(&stream);
 288
 289         while (1) {
 290                 st = inflate(&stream, Z_FINISH);
 291                 if (st == Z_STREAM_END || st == Z_OK) {
 292                         st = (stream.total_out == expect &&
 293                               stream.total_in == len) ? 0 : -1;
 294                         break;
 295                 }
 296                 if (st != Z_BUF_ERROR) {
 297                         st = -1;
 298                         break;
 299                 }
 300                 stream.next_out = fakebuf;
 301                 stream.avail_out = sizeof(fakebuf);
 302         }
 303         inflateEnd(&stream);
 304         return st;
 305 }
 306
 307 static int revalidate_loose_object(struct object_entry *entry,
 308                                    unsigned char *map,
 309                                    unsigned long mapsize)
 310 {
 311         /* we already know this is a loose object with new type header. */
 312         enum object_type type;
 313         unsigned long size, used;
 314
 315         if (pack_to_stdout)
 316                 return 0;
 317
 318         used = unpack_object_header_gently(map, mapsize, &type, &size);
 319         if (!used)
 320                 return -1;
 321         map += used;
 322         mapsize -= used;
 323         return check_inflate(map, mapsize, size);
 324 }
 325
 326 static unsigned long write_object(struct sha1file *f,
 327                                   struct object_entry *entry)
 328 {
 329         unsigned long size;
 330         char type[10];
 331         void *buf;
 332         unsigned char header[10];
 333         unsigned hdrlen, datalen;
 334         enum object_type obj_type;
 335         int to_reuse = 0;
 336
 337         obj_type = entry->type;
 338         if (! entry->in_pack)
 339                 to_reuse = 0;   /* can't reuse what we don't have */
 340         else if (obj_type == OBJ_REF_DELTA || obj_type == OBJ_OFS_DELTA)
 341                 to_reuse = 1;   /* check_object() decided it for us */
 342         else if (obj_type != entry->in_pack_type)
 343                 to_reuse = 0;   /* pack has delta which is unusable */
 344         else if (entry->delta)
 345                 to_reuse = 0;   /* we want to pack afresh */
 346         else
 347                 to_reuse = 1;   /* we have it in-pack undeltified,
 348                                  * and we do not need to deltify it.
 349                                  */
 350
 351         if (!entry->in_pack && !entry->delta) {
 352                 unsigned char *map;
 353                 unsigned long mapsize;
 354                 map = map_sha1_file(entry->sha1, &mapsize);
 355                 if (map && !legacy_loose_object(map)) {
 356                         /* We can copy straight into the pack file */
 357                         if (revalidate_loose_object(entry, map, mapsize))
 358                                 die("corrupt loose object %s",
 359                                     sha1_to_hex(entry->sha1));
 360                         sha1write(f, map, mapsize);
 361                         munmap(map, mapsize);
 362                         written++;
 363                         reused++;
 364                         return mapsize;
 365                 }
 366                 if (map)
 367                         munmap(map, mapsize);
 368         }
 369
 370         if (!to_reuse) {
 371                 buf = read_sha1_file(entry->sha1, type, &size);
 372                 if (!buf)
 373                         die("unable to read %s", sha1_to_hex(entry->sha1));
 374                 if (size != entry->size)
 375                         die("object %s size inconsistency (%lu vs %lu)",
 376                             sha1_to_hex(entry->sha1), size, entry->size);
 377                 if (entry->delta) {
 378                         buf = delta_against(buf, size, entry);
 379                         size = entry->delta_size;
 380                         obj_type = (allow_ofs_delta && entry->delta->offset) ?
 381                                 OBJ_OFS_DELTA : OBJ_REF_DELTA;
 382                 }
 383                 /*
 384                  * The object header is a byte of 'type' followed by zero or
 385                  * more bytes of length.
 386                  */
 387                 hdrlen = encode_header(obj_type, size, header);
 388                 sha1write(f, header, hdrlen);
 389
 390                 if (obj_type == OBJ_OFS_DELTA) {
 391                         /*
 392                          * Deltas with relative base contain an additional
 393                          * encoding of the relative offset for the delta
 394                          * base from this object's position in the pack.
 395                          */
 396                         unsigned long ofs = entry->offset - entry->delta->offset;
 397                         unsigned pos = sizeof(header) - 1;
 398                         header[pos] = ofs & 127;
 399                         while (ofs >>= 7)
 400                                 header[--pos] = 128 | (--ofs & 127);
 401                         sha1write(f, header + pos, sizeof(header) - pos);
 402                         hdrlen += sizeof(header) - pos;
 403                 } else if (obj_type == OBJ_REF_DELTA) {
 404                         /*
 405                          * Deltas with a base reference contain
 406                          * an additional 20 bytes for the base sha1.
 407                          */
 408                         sha1write(f, entry->delta->sha1, 20);
 409                         hdrlen += 20;
 410                 }
 411                 datalen = sha1write_compressed(f, buf, size);
 412                 free(buf);
 413         }
 414         else {
 415                 struct packed_git *p = entry->in_pack;
 416
 417                 if (entry->delta) {
 418                         obj_type = (allow_ofs_delta && entry->delta->offset) ?
 419                                 OBJ_OFS_DELTA : OBJ_REF_DELTA;
 420                         reused_delta++;
 421                 }
 422                 hdrlen = encode_header(obj_type, entry->size, header);
 423                 sha1write(f, header, hdrlen);
 424                 if (obj_type == OBJ_OFS_DELTA) {
 425                         unsigned long ofs = entry->offset - entry->delta->offset;
 426                         unsigned pos = sizeof(header) - 1;
 427                         header[pos] = ofs & 127;
 428                         while (ofs >>= 7)
 429                                 header[--pos] = 128 | (--ofs & 127);
 430                         sha1write(f, header + pos, sizeof(header) - pos);
 431                         hdrlen += sizeof(header) - pos;
 432                 } else if (obj_type == OBJ_REF_DELTA) {
 433                         sha1write(f, entry->delta->sha1, 20);
 434                         hdrlen += 20;
 435                 }
 436
 437                 use_packed_git(p);
 438                 buf = (char *) p->pack_base
 439                         + entry->in_pack_offset
 440                         + entry->in_pack_header_size;
 441                 datalen = find_packed_object_size(p, entry->in_pack_offset)
 442                                 - entry->in_pack_header_size;
 443 //fprintf(stderr, "reusing %d at %d header %d size %d\n", obj_type, entry->in_pack_offset, entry->in_pack_header_size, datalen);
 444                 if (!pack_to_stdout && check_inflate(buf, datalen, entry->size))
 445                         die("corrupt delta in pack %s", sha1_to_hex(entry->sha1));
 446                 sha1write(f, buf, datalen);
 447                 unuse_packed_git(p);
 448                 reused++;
 449         }
 450         if (entry->delta)
 451                 written_delta++;
 452         written++;
 453         return hdrlen + datalen;
 454 }
 455
 456 static unsigned long write_one(struct sha1file *f,
 457                                struct object_entry *e,
 458                                unsigned long offset)
 459 {
 460         if (e->offset || e->preferred_base)
 461                 /* offset starts from header size and cannot be zero
 462                  * if it is written already.
 463                  */
 464                 return offset;
 465         /* if we are deltified, write out its base object first. */
 466         if (e->delta)
 467                 offset = write_one(f, e->delta, offset);
 468         e->offset = offset;
 469         return offset + write_object(f, e);
 470 }
 471
 472 static void write_pack_file(void)
 473 {
 474         int i;
 475         struct sha1file *f;
 476         unsigned long offset;
 477         struct pack_header hdr;
 478         unsigned last_percent = 999;
 479         int do_progress = 0;
 480
 481         if (!base_name)
 482                 f = sha1fd(1, "<stdout>");
 483         else {
 484                 f = sha1create("%s-%s.%s", base_name,
 485                                sha1_to_hex(object_list_sha1), "pack");
 486                 do_progress = progress;
 487         }
 488         if (do_progress)
 489                 fprintf(stderr, "Writing %d objects.\n", nr_result);
 490
 491         hdr.hdr_signature = htonl(PACK_SIGNATURE);
 492         hdr.hdr_version = htonl(PACK_VERSION);
 493         hdr.hdr_entries = htonl(nr_result);
 494         sha1write(f, &hdr, sizeof(hdr));
 495         offset = sizeof(hdr);
 496         if (!nr_result)
 497                 goto done;
 498         for (i = 0; i < nr_objects; i++) {
 499                 offset = write_one(f, objects + i, offset);
 500                 if (do_progress) {
 501                         unsigned percent = written * 100 / nr_result;
 502                         if (progress_update || percent != last_percent) {
 503                                 fprintf(stderr, "%4u%% (%u/%u) done\r",
 504                                         percent, written, nr_result);
 505                                 progress_update = 0;
 506                                 last_percent = percent;
 507                         }
 508                 }
 509         }
 510         if (do_progress)
 511                 fputc('\n', stderr);
 512  done:
 513         sha1close(f, pack_file_sha1, 1);
 514 }
 515
 516 static void write_index_file(void)
 517 {
 518         int i;
 519         struct sha1file *f = sha1create("%s-%s.%s", base_name,
 520                                         sha1_to_hex(object_list_sha1), "idx");
 521         struct object_entry **list = sorted_by_sha;
 522         struct object_entry **last = list + nr_result;
 523         unsigned int array[256];
 524
 525         /*
 526          * Write the first-level table (the list is sorted,
 527          * but we use a 256-entry lookup to be able to avoid
 528          * having to do eight extra binary search iterations).
 529          */
 530         for (i = 0; i < 256; i++) {
 531                 struct object_entry **next = list;
 532                 while (next < last) {
 533                         struct object_entry *entry = *next;
 534                         if (entry->sha1[0] != i)
 535                                 break;
 536                         next++;
 537                 }
 538                 array[i] = htonl(next - sorted_by_sha);
 539                 list = next;
 540         }
 541         sha1write(f, array, 256 * sizeof(int));
 542
 543         /*
 544          * Write the actual SHA1 entries..
 545          */
 546         list = sorted_by_sha;
 547         for (i = 0; i < nr_result; i++) {
 548                 struct object_entry *entry = *list++;
 549                 unsigned int offset = htonl(entry->offset);
 550                 sha1write(f, &offset, 4);
 551                 sha1write(f, entry->sha1, 20);
 552         }
 553         sha1write(f, pack_file_sha1, 20);
 554         sha1close(f, NULL, 1);
 555 }
 556
 557 static int locate_object_entry_hash(const unsigned char *sha1)
 558 {
 559         int i;
 560         unsigned int ui;
 561         memcpy(&ui, sha1, sizeof(unsigned int));
 562         i = ui % object_ix_hashsz;
 563         while (0 < object_ix[i]) {
 564                 if (!hashcmp(sha1, objects[object_ix[i] - 1].sha1))
 565                         return i;
 566                 if (++i == object_ix_hashsz)
 567                         i = 0;
 568         }
 569         return -1 - i;
 570 }
 571
 572 static struct object_entry *locate_object_entry(const unsigned char *sha1)
 573 {
 574         int i;
 575
 576         if (!object_ix_hashsz)
 577                 return NULL;
 578
 579         i = locate_object_entry_hash(sha1);
 580         if (0 <= i)
 581                 return &objects[object_ix[i]-1];
 582         return NULL;
 583 }
 584
 585 static void rehash_objects(void)
 586 {
 587         int i;
 588         struct object_entry *oe;
 589
 590         object_ix_hashsz = nr_objects * 3;
 591         if (object_ix_hashsz < 1024)
 592                 object_ix_hashsz = 1024;
 593         object_ix = xrealloc(object_ix, sizeof(int) * object_ix_hashsz);
 594         memset(object_ix, 0, sizeof(int) * object_ix_hashsz);
 595         for (i = 0, oe = objects; i < nr_objects; i++, oe++) {
 596                 int ix = locate_object_entry_hash(oe->sha1);
 597                 if (0 <= ix)
 598                         continue;
 599                 ix = -1 - ix;
 600                 object_ix[ix] = i + 1;
 601         }
 602 }
 603
 604 static unsigned name_hash(const char *name)
 605 {
 606         unsigned char c;
 607         unsigned hash = 0;
 608
 609         /*
 610          * This effectively just creates a sortable number from the
 611          * last sixteen non-whitespace characters. Last characters
 612          * count "most", so things that end in ".c" sort together.
 613          */
 614         while ((c = *name++) != 0) {
 615                 if (isspace(c))
 616                         continue;
 617                 hash = (hash >> 2) + (c << 24);
 618         }
 619         return hash;
 620 }
 621
 622 static int add_object_entry(const unsigned char *sha1, unsigned hash, int exclude)
 623 {
 624         unsigned int idx = nr_objects;
 625         struct object_entry *entry;
 626         struct packed_git *p;
 627         unsigned int found_offset = 0;
 628         struct packed_git *found_pack = NULL;
 629         int ix, status = 0;
 630
 631         if (!exclude) {
 632                 for (p = packed_git; p; p = p->next) {
 633                         unsigned long offset = find_pack_entry_one(sha1, p);
 634                         if (offset) {
 635                                 if (incremental)
 636                                         return 0;
 637                                 if (local && !p->pack_local)
 638                                         return 0;
 639                                 if (!found_pack) {
 640                                         found_offset = offset;
 641                                         found_pack = p;
 642                                 }
 643                         }
 644                 }
 645         }
 646         if ((entry = locate_object_entry(sha1)) != NULL)
 647                 goto already_added;
 648
 649         if (idx >= nr_alloc) {
 650                 unsigned int needed = (idx + 1024) * 3 / 2;
 651                 objects = xrealloc(objects, needed * sizeof(*entry));
 652                 nr_alloc = needed;
 653         }
 654         entry = objects + idx;
 655         nr_objects = idx + 1;
 656         memset(entry, 0, sizeof(*entry));
 657         hashcpy(entry->sha1, sha1);
 658         entry->hash = hash;
 659
 660         if (object_ix_hashsz * 3 <= nr_objects * 4)
 661                 rehash_objects();
 662         else {
 663                 ix = locate_object_entry_hash(entry->sha1);
 664                 if (0 <= ix)
 665                         die("internal error in object hashing.");
 666                 object_ix[-1 - ix] = idx + 1;
 667         }
 668         status = 1;
 669
 670  already_added:
 671         if (progress_update) {
 672                 fprintf(stderr, "Counting objects...%d\r", nr_objects);
 673                 progress_update = 0;
 674         }
 675         if (exclude)
 676                 entry->preferred_base = 1;
 677         else {
 678                 if (found_pack) {
 679                         entry->in_pack = found_pack;
 680                         entry->in_pack_offset = found_offset;
 681                 }
 682         }
 683         return status;
 684 }
 685
 686 struct pbase_tree_cache {
 687         unsigned char sha1[20];
 688         int ref;
 689         int temporary;
 690         void *tree_data;
 691         unsigned long tree_size;
 692 };
 693
 694 static struct pbase_tree_cache *(pbase_tree_cache[256]);
 695 static int pbase_tree_cache_ix(const unsigned char *sha1)
 696 {
 697         return sha1[0] % ARRAY_SIZE(pbase_tree_cache);
 698 }
 699 static int pbase_tree_cache_ix_incr(int ix)
 700 {
 701         return (ix+1) % ARRAY_SIZE(pbase_tree_cache);
 702 }
 703
 704 static struct pbase_tree {
 705         struct pbase_tree *next;
 706         /* This is a phony "cache" entry; we are not
 707          * going to evict it nor find it through _get()
 708          * mechanism -- this is for the toplevel node that
 709          * would almost always change with any commit.
 710          */
 711         struct pbase_tree_cache pcache;
 712 } *pbase_tree;
 713
 714 static struct pbase_tree_cache *pbase_tree_get(const unsigned char *sha1)
 715 {
 716         struct pbase_tree_cache *ent, *nent;
 717         void *data;
 718         unsigned long size;
 719         char type[20];
 720         int neigh;
 721         int my_ix = pbase_tree_cache_ix(sha1);
 722         int available_ix = -1;
 723
 724         /* pbase-tree-cache acts as a limited hashtable.
 725          * your object will be found at your index or within a few
 726          * slots after that slot if it is cached.
 727          */
 728         for (neigh = 0; neigh < 8; neigh++) {
 729                 ent = pbase_tree_cache[my_ix];
 730                 if (ent && !hashcmp(ent->sha1, sha1)) {
 731                         ent->ref++;
 732                         return ent;
 733                 }
 734                 else if (((available_ix < 0) && (!ent || !ent->ref)) ||
 735                          ((0 <= available_ix) &&
 736                           (!ent && pbase_tree_cache[available_ix])))
 737                         available_ix = my_ix;
 738                 if (!ent)
 739                         break;
 740                 my_ix = pbase_tree_cache_ix_incr(my_ix);
 741         }
 742
 743         /* Did not find one.  Either we got a bogus request or
 744          * we need to read and perhaps cache.
 745          */
 746         data = read_sha1_file(sha1, type, &size);
 747         if (!data)
 748                 return NULL;
 749         if (strcmp(type, tree_type)) {
 750                 free(data);
 751                 return NULL;
 752         }
 753
 754         /* We need to either cache or return a throwaway copy */
 755
 756         if (available_ix < 0)
 757                 ent = NULL;
 758         else {
 759                 ent = pbase_tree_cache[available_ix];
 760                 my_ix = available_ix;
 761         }
 762
 763         if (!ent) {
 764                 nent = xmalloc(sizeof(*nent));
 765                 nent->temporary = (available_ix < 0);
 766         }
 767         else {
 768                 /* evict and reuse */
 769                 free(ent->tree_data);
 770                 nent = ent;
 771         }
 772         hashcpy(nent->sha1, sha1);
 773         nent->tree_data = data;
 774         nent->tree_size = size;
 775         nent->ref = 1;
 776         if (!nent->temporary)
 777                 pbase_tree_cache[my_ix] = nent;
 778         return nent;
 779 }
 780
 781 static void pbase_tree_put(struct pbase_tree_cache *cache)
 782 {
 783         if (!cache->temporary) {
 784                 cache->ref--;
 785                 return;
 786         }
 787         free(cache->tree_data);
 788         free(cache);
 789 }
 790
 791 static int name_cmp_len(const char *name)
 792 {
 793         int i;
 794         for (i = 0; name[i] && name[i] != '\n' && name[i] != '/'; i++)
 795                 ;
 796         return i;
 797 }
 798
 799 static void add_pbase_object(struct tree_desc *tree,
 800                              const char *name,
 801                              int cmplen,
 802                              const char *fullname)
 803 {
 804         struct name_entry entry;
 805
 806         while (tree_entry(tree,&entry)) {
 807                 unsigned long size;
 808                 char type[20];
 809
 810                 if (entry.pathlen != cmplen ||
 811                     memcmp(entry.path, name, cmplen) ||
 812                     !has_sha1_file(entry.sha1) ||
 813                     sha1_object_info(entry.sha1, type, &size))
 814                         continue;
 815                 if (name[cmplen] != '/') {
 816                         unsigned hash = name_hash(fullname);
 817                         add_object_entry(entry.sha1, hash, 1);
 818                         return;
 819                 }
 820                 if (!strcmp(type, tree_type)) {
 821                         struct tree_desc sub;
 822                         struct pbase_tree_cache *tree;
 823                         const char *down = name+cmplen+1;
 824                         int downlen = name_cmp_len(down);
 825
 826                         tree = pbase_tree_get(entry.sha1);
 827                         if (!tree)
 828                                 return;
 829                         sub.buf = tree->tree_data;
 830                         sub.size = tree->tree_size;
 831
 832                         add_pbase_object(&sub, down, downlen, fullname);
 833                         pbase_tree_put(tree);
 834                 }
 835         }
 836 }
 837
 838 static unsigned *done_pbase_paths;
 839 static int done_pbase_paths_num;
 840 static int done_pbase_paths_alloc;
 841 static int done_pbase_path_pos(unsigned hash)
 842 {
 843         int lo = 0;
 844         int hi = done_pbase_paths_num;
 845         while (lo < hi) {
 846                 int mi = (hi + lo) / 2;
 847                 if (done_pbase_paths[mi] == hash)
 848                         return mi;
 849                 if (done_pbase_paths[mi] < hash)
 850                         hi = mi;
 851                 else
 852                         lo = mi + 1;
 853         }
 854         return -lo-1;
 855 }
 856
 857 static int check_pbase_path(unsigned hash)
 858 {
 859         int pos = (!done_pbase_paths) ? -1 : done_pbase_path_pos(hash);
 860         if (0 <= pos)
 861                 return 1;
 862         pos = -pos - 1;
 863         if (done_pbase_paths_alloc <= done_pbase_paths_num) {
 864                 done_pbase_paths_alloc = alloc_nr(done_pbase_paths_alloc);
 865                 done_pbase_paths = xrealloc(done_pbase_paths,
 866                                             done_pbase_paths_alloc *
 867                                             sizeof(unsigned));
 868         }
 869         done_pbase_paths_num++;
 870         if (pos < done_pbase_paths_num)
 871                 memmove(done_pbase_paths + pos + 1,
 872                         done_pbase_paths + pos,
 873                         (done_pbase_paths_num - pos - 1) * sizeof(unsigned));
 874         done_pbase_paths[pos] = hash;
 875         return 0;
 876 }
 877
 878 static void add_preferred_base_object(const char *name, unsigned hash)
 879 {
 880         struct pbase_tree *it;
 881         int cmplen = name_cmp_len(name);
 882
 883         if (check_pbase_path(hash))
 884                 return;
 885
 886         for (it = pbase_tree; it; it = it->next) {
 887                 if (cmplen == 0) {
 888                         hash = name_hash("");
 889                         add_object_entry(it->pcache.sha1, hash, 1);
 890                 }
 891                 else {
 892                         struct tree_desc tree;
 893                         tree.buf = it->pcache.tree_data;
 894                         tree.size = it->pcache.tree_size;
 895                         add_pbase_object(&tree, name, cmplen, name);
 896                 }
 897         }
 898 }
 899
 900 static void add_preferred_base(unsigned char *sha1)
 901 {
 902         struct pbase_tree *it;
 903         void *data;
 904         unsigned long size;
 905         unsigned char tree_sha1[20];
 906
 907         if (window <= num_preferred_base++)
 908                 return;
 909
 910         data = read_object_with_reference(sha1, tree_type, &size, tree_sha1);
 911         if (!data)
 912                 return;
 913
 914         for (it = pbase_tree; it; it = it->next) {
 915                 if (!hashcmp(it->pcache.sha1, tree_sha1)) {
 916                         free(data);
 917                         return;
 918                 }
 919         }
 920
 921         it = xcalloc(1, sizeof(*it));
 922         it->next = pbase_tree;
 923         pbase_tree = it;
 924
 925         hashcpy(it->pcache.sha1, tree_sha1);
 926         it->pcache.tree_data = data;
 927         it->pcache.tree_size = size;
 928 }
 929
 930 static void check_object(struct object_entry *entry)
 931 {
 932         char type[20];
 933
 934         if (entry->in_pack && !entry->preferred_base) {
 935                 struct packed_git *p = entry->in_pack;
 936                 unsigned long left = p->pack_size - entry->in_pack_offset;
 937                 unsigned long size, used;
 938                 unsigned char *buf;
 939                 struct object_entry *base_entry = NULL;
 940
 941                 use_packed_git(p);
 942                 buf = p->pack_base;
 943                 buf += entry->in_pack_offset;
 944
 945                 /* We want in_pack_type even if we do not reuse delta.
 946                  * There is no point not reusing non-delta representations.
 947                  */
 948                 used = unpack_object_header_gently(buf, left,
 949                                                    &entry->in_pack_type, &size);
 950                 if (!used || left - used <= 20)
 951                         die("corrupt pack for %s", sha1_to_hex(entry->sha1));
 952
 953                 /* Check if it is delta, and the base is also an object
 954                  * we are going to pack.  If so we will reuse the existing
 955                  * delta.
 956                  */
 957                 if (!no_reuse_delta) {
 958                         unsigned char c, *base_name;
 959                         unsigned long ofs;
 960                         /* there is at least 20 bytes left in the pack */
 961                         switch (entry->in_pack_type) {
 962                         case OBJ_REF_DELTA:
 963                                 base_name = buf + used;
 964                                 used += 20;
 965                                 break;
 966                         case OBJ_OFS_DELTA:
 967                                 c = buf[used++];
 968                                 ofs = c & 127;
 969                                 while (c & 128) {
 970                                         ofs += 1;
 971                                         if (!ofs || ofs & ~(~0UL >> 7))
 972                                                 die("delta base offset overflow in pack for %s",
 973                                                     sha1_to_hex(entry->sha1));
 974                                         c = buf[used++];
 975                                         ofs = (ofs << 7) + (c & 127);
 976                                 }
 977                                 if (ofs >= entry->in_pack_offset)
 978                                         die("delta base offset out of bound for %s",
 979                                             sha1_to_hex(entry->sha1));
 980                                 ofs = entry->in_pack_offset - ofs;
 981                                 base_name = find_packed_object_name(p, ofs);
 982                                 break;
 983                         default:
 984                                 base_name = NULL;
 985                         }
 986                         if (base_name)
 987                                 base_entry = locate_object_entry(base_name);
 988                 }
 989                 unuse_packed_git(p);
 990                 entry->in_pack_header_size = used;
 991
 992                 if (base_entry && !base_entry->preferred_base) {
 993
 994                         /* Depth value does not matter - find_deltas()
 995                          * will never consider reused delta as the
 996                          * base object to deltify other objects
 997                          * against, in order to avoid circular deltas.
 998                          */
 999
1000                         /* uncompressed size of the delta data */
1001                         entry->size = size;
1002                         entry->delta = base_entry;
1003                         entry->type = entry->in_pack_type;
1004
1005                         entry->delta_sibling = base_entry->delta_child;
1006                         base_entry->delta_child = entry;
1007
1008                         return;
1009                 }
1010                 /* Otherwise we would do the usual */
1011         }
1012
1013         if (sha1_object_info(entry->sha1, type, &entry->size))
1014                 die("unable to get type of object %s",
1015                     sha1_to_hex(entry->sha1));
1016
1017         if (!strcmp(type, commit_type)) {
1018                 entry->type = OBJ_COMMIT;
1019         } else if (!strcmp(type, tree_type)) {
1020                 entry->type = OBJ_TREE;
1021         } else if (!strcmp(type, blob_type)) {
1022                 entry->type = OBJ_BLOB;
1023         } else if (!strcmp(type, tag_type)) {
1024                 entry->type = OBJ_TAG;
1025         } else
1026                 die("unable to pack object %s of type %s",
1027                     sha1_to_hex(entry->sha1), type);
1028 }
1029
1030 static unsigned int check_delta_limit(struct object_entry *me, unsigned int n)
1031 {
1032         struct object_entry *child = me->delta_child;
1033         unsigned int m = n;
1034         while (child) {
1035                 unsigned int c = check_delta_limit(child, n + 1);
1036                 if (m < c)
1037                         m = c;
1038                 child = child->delta_sibling;
1039         }
1040         return m;
1041 }
1042
1043 static void get_object_details(void)
1044 {
1045         int i;
1046         struct object_entry *entry;
1047
1048         prepare_pack_ix();
1049         for (i = 0, entry = objects; i < nr_objects; i++, entry++)
1050                 check_object(entry);
1051
1052         if (nr_objects == nr_result) {
1053                 /*
1054                  * Depth of objects that depend on the entry -- this
1055                  * is subtracted from depth-max to break too deep
1056                  * delta chain because of delta data reusing.
1057                  * However, we loosen this restriction when we know we
1058                  * are creating a thin pack -- it will have to be
1059                  * expanded on the other end anyway, so do not
1060                  * artificially cut the delta chain and let it go as
1061                  * deep as it wants.
1062                  */
1063                 for (i = 0, entry = objects; i < nr_objects; i++, entry++)
1064                         if (!entry->delta && entry->delta_child)
1065                                 entry->delta_limit =
1066                                         check_delta_limit(entry, 1);
1067         }
1068 }
1069
1070 typedef int (*entry_sort_t)(const struct object_entry *, const struct object_entry *);
1071
1072 static entry_sort_t current_sort;
1073
1074 static int sort_comparator(const void *_a, const void *_b)
1075 {
1076         struct object_entry *a = *(struct object_entry **)_a;
1077         struct object_entry *b = *(struct object_entry **)_b;
1078         return current_sort(a,b);
1079 }
1080
1081 static struct object_entry **create_sorted_list(entry_sort_t sort)
1082 {
1083         struct object_entry **list = xmalloc(nr_objects * sizeof(struct object_entry *));
1084         int i;
1085
1086         for (i = 0; i < nr_objects; i++)
1087                 list[i] = objects + i;
1088         current_sort = sort;
1089         qsort(list, nr_objects, sizeof(struct object_entry *), sort_comparator);
1090         return list;
1091 }
1092
1093 static int sha1_sort(const struct object_entry *a, const struct object_entry *b)
1094 {
1095         return hashcmp(a->sha1, b->sha1);
1096 }
1097
1098 static struct object_entry **create_final_object_list(void)
1099 {
1100         struct object_entry **list;
1101         int i, j;
1102
1103         for (i = nr_result = 0; i < nr_objects; i++)
1104                 if (!objects[i].preferred_base)
1105                         nr_result++;
1106         list = xmalloc(nr_result * sizeof(struct object_entry *));
1107         for (i = j = 0; i < nr_objects; i++) {
1108                 if (!objects[i].preferred_base)
1109                         list[j++] = objects + i;
1110         }
1111         current_sort = sha1_sort;
1112         qsort(list, nr_result, sizeof(struct object_entry *), sort_comparator);
1113         return list;
1114 }
1115
1116 static int type_size_sort(const struct object_entry *a, const struct object_entry *b)
1117 {
1118         if (a->type < b->type)
1119                 return -1;
1120         if (a->type > b->type)
1121                 return 1;
1122         if (a->hash < b->hash)
1123                 return -1;
1124         if (a->hash > b->hash)
1125                 return 1;
1126         if (a->preferred_base < b->preferred_base)
1127                 return -1;
1128         if (a->preferred_base > b->preferred_base)
1129                 return 1;
1130         if (a->size < b->size)
1131                 return -1;
1132         if (a->size > b->size)
1133                 return 1;
1134         return a < b ? -1 : (a > b);
1135 }
1136
1137 struct unpacked {
1138         struct object_entry *entry;
1139         void *data;
1140         struct delta_index *index;
1141 };
1142
1143 /*
1144  * We search for deltas _backwards_ in a list sorted by type and
1145  * by size, so that we see progressively smaller and smaller files.
1146  * That's because we prefer deltas to be from the bigger file
1147  * to the smaller - deletes are potentially cheaper, but perhaps
1148  * more importantly, the bigger file is likely the more recent
1149  * one.
1150  */
1151 static int try_delta(struct unpacked *trg, struct unpacked *src,
1152                      unsigned max_depth)
1153 {
1154         struct object_entry *trg_entry = trg->entry;
1155         struct object_entry *src_entry = src->entry;
1156         unsigned long trg_size, src_size, delta_size, sizediff, max_size, sz;
1157         char type[10];
1158         void *delta_buf;
1159
1160         /* Don't bother doing diffs between different types */
1161         if (trg_entry->type != src_entry->type)
1162                 return -1;
1163
1164         /* We do not compute delta to *create* objects we are not
1165          * going to pack.
1166          */
1167         if (trg_entry->preferred_base)
1168                 return -1;
1169
1170         /*
1171          * We do not bother to try a delta that we discarded
1172          * on an earlier try, but only when reusing delta data.
1173          */
1174         if (!no_reuse_delta && trg_entry->in_pack &&
1175             trg_entry->in_pack == src_entry->in_pack)
1176                 return 0;
1177
1178         /*
1179          * If the current object is at pack edge, take the depth the
1180          * objects that depend on the current object into account --
1181          * otherwise they would become too deep.
1182          */
1183         if (trg_entry->delta_child) {
1184                 if (max_depth <= trg_entry->delta_limit)
1185                         return 0;
1186                 max_depth -= trg_entry->delta_limit;
1187         }
1188         if (src_entry->depth >= max_depth)
1189                 return 0;
1190
1191         /* Now some size filtering heuristics. */
1192         trg_size = trg_entry->size;
1193         max_size = trg_size/2 - 20;
1194         max_size = max_size * (max_depth - src_entry->depth) / max_depth;
1195         if (max_size == 0)
1196                 return 0;
1197         if (trg_entry->delta && trg_entry->delta_size <= max_size)
1198                 max_size = trg_entry->delta_size-1;
1199         src_size = src_entry->size;
1200         sizediff = src_size < trg_size ? trg_size - src_size : 0;
1201         if (sizediff >= max_size)
1202                 return 0;
1203
1204         /* Load data if not already done */
1205         if (!trg->data) {
1206                 trg->data = read_sha1_file(trg_entry->sha1, type, &sz);
1207                 if (sz != trg_size)
1208                         die("object %s inconsistent object length (%lu vs %lu)",
1209                             sha1_to_hex(trg_entry->sha1), sz, trg_size);
1210         }
1211         if (!src->data) {
1212                 src->data = read_sha1_file(src_entry->sha1, type, &sz);
1213                 if (sz != src_size)
1214                         die("object %s inconsistent object length (%lu vs %lu)",
1215                             sha1_to_hex(src_entry->sha1), sz, src_size);
1216         }
1217         if (!src->index) {
1218                 src->index = create_delta_index(src->data, src_size);
1219                 if (!src->index)
1220                         die("out of memory");
1221         }
1222
1223         delta_buf = create_delta(src->index, trg->data, trg_size, &delta_size, max_size);
1224         if (!delta_buf)
1225                 return 0;
1226
1227         trg_entry->delta = src_entry;
1228         trg_entry->delta_size = delta_size;
1229         trg_entry->depth = src_entry->depth + 1;
1230         free(delta_buf);
1231         return 1;
1232 }
1233
1234 static void progress_interval(int signum)
1235 {
1236         progress_update = 1;
1237 }
1238
1239 static void find_deltas(struct object_entry **list, int window, int depth)
1240 {
1241         int i, idx;
1242         unsigned int array_size = window * sizeof(struct unpacked);
1243         struct unpacked *array = xmalloc(array_size);
1244         unsigned processed = 0;
1245         unsigned last_percent = 999;
1246
1247         memset(array, 0, array_size);
1248         i = nr_objects;
1249         idx = 0;
1250         if (progress)
1251                 fprintf(stderr, "Deltifying %d objects.\n", nr_result);
1252
1253         while (--i >= 0) {
1254                 struct object_entry *entry = list[i];
1255                 struct unpacked *n = array + idx;
1256                 int j;
1257
1258                 if (!entry->preferred_base)
1259                         processed++;
1260
1261                 if (progress) {
1262                         unsigned percent = processed * 100 / nr_result;
1263                         if (percent != last_percent || progress_update) {
1264                                 fprintf(stderr, "%4u%% (%u/%u) done\r",
1265                                         percent, processed, nr_result);
1266                                 progress_update = 0;
1267                                 last_percent = percent;
1268                         }
1269                 }
1270
1271                 if (entry->delta)
1272                         /* This happens if we decided to reuse existing
1273                          * delta from a pack.  "!no_reuse_delta &&" is implied.
1274                          */
1275                         continue;
1276
1277                 if (entry->size < 50)
1278                         continue;
1279                 free_delta_index(n->index);
1280                 n->index = NULL;
1281                 free(n->data);
1282                 n->data = NULL;
1283                 n->entry = entry;
1284
1285                 j = window;
1286                 while (--j > 0) {
1287                         unsigned int other_idx = idx + j;
1288                         struct unpacked *m;
1289                         if (other_idx >= window)
1290                                 other_idx -= window;
1291                         m = array + other_idx;
1292                         if (!m->entry)
1293                                 break;
1294                         if (try_delta(n, m, depth) < 0)
1295                                 break;
1296                 }
1297                 /* if we made n a delta, and if n is already at max
1298                  * depth, leaving it in the window is pointless.  we
1299                  * should evict it first.
1300                  */
1301                 if (entry->delta && depth <= entry->depth)
1302                         continue;
1303
1304                 idx++;
1305                 if (idx >= window)
1306                         idx = 0;
1307         }
1308
1309         if (progress)
1310                 fputc('\n', stderr);
1311
1312         for (i = 0; i < window; ++i) {
1313                 free_delta_index(array[i].index);
1314                 free(array[i].data);
1315         }
1316         free(array);
1317 }
1318
1319 static void prepare_pack(int window, int depth)
1320 {
1321         get_object_details();
1322         sorted_by_type = create_sorted_list(type_size_sort);
1323         if (window && depth)
1324                 find_deltas(sorted_by_type, window+1, depth);
1325 }
1326
1327 static int reuse_cached_pack(unsigned char *sha1)
1328 {
1329         static const char cache[] = "pack-cache/pack-%s.%s";
1330         char *cached_pack, *cached_idx;
1331         int ifd, ofd, ifd_ix = -1;
1332
1333         cached_pack = git_path(cache, sha1_to_hex(sha1), "pack");
1334         ifd = open(cached_pack, O_RDONLY);
1335         if (ifd < 0)
1336                 return 0;
1337
1338         if (!pack_to_stdout) {
1339                 cached_idx = git_path(cache, sha1_to_hex(sha1), "idx");
1340                 ifd_ix = open(cached_idx, O_RDONLY);
1341                 if (ifd_ix < 0) {
1342                         close(ifd);
1343                         return 0;
1344                 }
1345         }
1346
1347         if (progress)
1348                 fprintf(stderr, "Reusing %d objects pack %s\n", nr_objects,
1349                         sha1_to_hex(sha1));
1350
1351         if (pack_to_stdout) {
1352                 if (copy_fd(ifd, 1))
1353                         exit(1);
1354                 close(ifd);
1355         }
1356         else {
1357                 char name[PATH_MAX];
1358                 snprintf(name, sizeof(name),
1359                          "%s-%s.%s", base_name, sha1_to_hex(sha1), "pack");
1360                 ofd = open(name, O_CREAT | O_EXCL | O_WRONLY, 0666);
1361                 if (ofd < 0)
1362                         die("unable to open %s (%s)", name, strerror(errno));
1363                 if (copy_fd(ifd, ofd))
1364                         exit(1);
1365                 close(ifd);
1366
1367                 snprintf(name, sizeof(name),
1368                          "%s-%s.%s", base_name, sha1_to_hex(sha1), "idx");
1369                 ofd = open(name, O_CREAT | O_EXCL | O_WRONLY, 0666);
1370                 if (ofd < 0)
1371                         die("unable to open %s (%s)", name, strerror(errno));
1372                 if (copy_fd(ifd_ix, ofd))
1373                         exit(1);
1374                 close(ifd_ix);
1375                 puts(sha1_to_hex(sha1));
1376         }
1377
1378         return 1;
1379 }
1380
1381 static void setup_progress_signal(void)
1382 {
1383         struct sigaction sa;
1384         struct itimerval v;
1385
1386         memset(&sa, 0, sizeof(sa));
1387         sa.sa_handler = progress_interval;
1388         sigemptyset(&sa.sa_mask);
1389         sa.sa_flags = SA_RESTART;
1390         sigaction(SIGALRM, &sa, NULL);
1391
1392         v.it_interval.tv_sec = 1;
1393         v.it_interval.tv_usec = 0;
1394         v.it_value = v.it_interval;
1395         setitimer(ITIMER_REAL, &v, NULL);
1396 }
1397
1398 static int git_pack_config(const char *k, const char *v)
1399 {
1400         if(!strcmp(k, "pack.window")) {
1401                 window = git_config_int(k, v);
1402                 return 0;
1403         }
1404         return git_default_config(k, v);
1405 }
1406
1407 static void read_object_list_from_stdin(void)
1408 {
1409         char line[40 + 1 + PATH_MAX + 2];
1410         unsigned char sha1[20];
1411         unsigned hash;
1412
1413         for (;;) {
1414                 if (!fgets(line, sizeof(line), stdin)) {
1415                         if (feof(stdin))
1416                                 break;
1417                         if (!ferror(stdin))
1418                                 die("fgets returned NULL, not EOF, not error!");
1419                         if (errno != EINTR)
1420                                 die("fgets: %s", strerror(errno));
1421                         clearerr(stdin);
1422                         continue;
1423                 }
1424                 if (line[0] == '-') {
1425                         if (get_sha1_hex(line+1, sha1))
1426                                 die("expected edge sha1, got garbage:\n %s",
1427                                     line);
1428                         add_preferred_base(sha1);
1429                         continue;
1430                 }
1431                 if (get_sha1_hex(line, sha1))
1432                         die("expected sha1, got garbage:\n %s", line);
1433
1434                 hash = name_hash(line+41);
1435                 add_preferred_base_object(line+41, hash);
1436                 add_object_entry(sha1, hash, 0);
1437         }
1438 }
1439
1440 static void show_commit(struct commit *commit)
1441 {
1442         unsigned hash = name_hash("");
1443         add_preferred_base_object("", hash);
1444         add_object_entry(commit->object.sha1, hash, 0);
1445 }
1446
1447 static void show_object(struct object_array_entry *p)
1448 {
1449         unsigned hash = name_hash(p->name);
1450         add_preferred_base_object(p->name, hash);
1451         add_object_entry(p->item->sha1, hash, 0);
1452 }
1453
1454 static void show_edge(struct commit *commit)
1455 {
1456         add_preferred_base(commit->object.sha1);
1457 }
1458
1459 static void get_object_list(int ac, const char **av)
1460 {
1461         struct rev_info revs;
1462         char line[1000];
1463         int flags = 0;
1464
1465         init_revisions(&revs, NULL);
1466         save_commit_buffer = 0;
1467         track_object_refs = 0;
1468         setup_revisions(ac, av, &revs, NULL);
1469
1470         while (fgets(line, sizeof(line), stdin) != NULL) {
1471                 int len = strlen(line);
1472                 if (line[len - 1] == '\n')
1473                         line[--len] = 0;
1474                 if (!len)
1475                         break;
1476                 if (*line == '-') {
1477                         if (!strcmp(line, "--not")) {
1478                                 flags ^= UNINTERESTING;
1479                                 continue;
1480                         }
1481                         die("not a rev '%s'", line);
1482                 }
1483                 if (handle_revision_arg(line, &revs, flags, 1))
1484                         die("bad revision '%s'", line);
1485         }
1486
1487         prepare_revision_walk(&revs);
1488         mark_edges_uninteresting(revs.commits, &revs, show_edge);
1489         traverse_commit_list(&revs, show_commit, show_object);
1490 }
1491
1492 int cmd_pack_objects(int argc, const char **argv, const char *prefix)
1493 {
1494         SHA_CTX ctx;
1495         int depth = 10;
1496         struct object_entry **list;
1497         int use_internal_rev_list = 0;
1498         int thin = 0;
1499         int i;
1500         const char *rp_av[64];
1501         int rp_ac;
1502
1503         rp_av[0] = "pack-objects";
1504         rp_av[1] = "--objects"; /* --thin will make it --objects-edge */
1505         rp_ac = 2;
1506
1507         git_config(git_pack_config);
1508
1509         progress = isatty(2);
1510         for (i = 1; i < argc; i++) {
1511                 const char *arg = argv[i];
1512
1513                 if (*arg != '-')
1514                         break;
1515
1516                 if (!strcmp("--non-empty", arg)) {
1517                         non_empty = 1;
1518                         continue;
1519                 }
1520                 if (!strcmp("--local", arg)) {
1521                         local = 1;
1522                         continue;
1523                 }
1524                 if (!strcmp("--progress", arg)) {
1525                         progress = 1;
1526                         continue;
1527                 }
1528                 if (!strcmp("--incremental", arg)) {
1529                         incremental = 1;
1530                         continue;
1531                 }
1532                 if (!strncmp("--window=", arg, 9)) {
1533                         char *end;
1534                         window = strtoul(arg+9, &end, 0);
1535                         if (!arg[9] || *end)
1536                                 usage(pack_usage);
1537                         continue;
1538                 }
1539                 if (!strncmp("--depth=", arg, 8)) {
1540                         char *end;
1541                         depth = strtoul(arg+8, &end, 0);
1542                         if (!arg[8] || *end)
1543                                 usage(pack_usage);
1544                         continue;
1545                 }
1546                 if (!strcmp("--progress", arg)) {
1547                         progress = 1;
1548                         continue;
1549                 }
1550                 if (!strcmp("-q", arg)) {
1551                         progress = 0;
1552                         continue;
1553                 }
1554                 if (!strcmp("--no-reuse-delta", arg)) {
1555                         no_reuse_delta = 1;
1556                         continue;
1557                 }
1558                 if (!strcmp("--delta-base-offset", arg)) {
1559                         allow_ofs_delta = 1;
1560                         continue;
1561                 }
1562                 if (!strcmp("--stdout", arg)) {
1563                         pack_to_stdout = 1;
1564                         continue;
1565                 }
1566                 if (!strcmp("--revs", arg)) {
1567                         use_internal_rev_list = 1;
1568                         continue;
1569                 }
1570                 if (!strcmp("--unpacked", arg) ||
1571                     !strncmp("--unpacked=", arg, 11) ||
1572                     !strcmp("--all", arg)) {
1573                         use_internal_rev_list = 1;
1574                         if (ARRAY_SIZE(rp_av) - 1 <= rp_ac)
1575                                 die("too many internal rev-list options");
1576                         rp_av[rp_ac++] = arg;
1577                         continue;
1578                 }
1579                 if (!strcmp("--thin", arg)) {
1580                         use_internal_rev_list = 1;
1581                         thin = 1;
1582                         rp_av[1] = "--objects-edge";
1583                         continue;
1584                 }
1585                 usage(pack_usage);
1586         }
1587
1588         /* Traditionally "pack-objects [options] base extra" failed;
1589          * we would however want to take refs parameter that would
1590          * have been given to upstream rev-list ourselves, which means
1591          * we somehow want to say what the base name is.  So the
1592          * syntax would be:
1593          *
1594          * pack-objects [options] base <refs...>
1595          *
1596          * in other words, we would treat the first non-option as the
1597          * base_name and send everything else to the internal revision
1598          * walker.
1599          */
1600
1601         if (!pack_to_stdout)
1602                 base_name = argv[i++];
1603
1604         if (pack_to_stdout != !base_name)
1605                 usage(pack_usage);
1606
1607         if (!pack_to_stdout && thin)
1608                 die("--thin cannot be used to build an indexable pack.");
1609
1610         prepare_packed_git();
1611
1612         if (progress) {
1613                 fprintf(stderr, "Generating pack...\n");
1614                 setup_progress_signal();
1615         }
1616
1617         if (!use_internal_rev_list)
1618                 read_object_list_from_stdin();
1619         else {
1620                 rp_av[rp_ac] = NULL;
1621                 get_object_list(rp_ac, rp_av);
1622         }
1623
1624         if (progress)
1625                 fprintf(stderr, "Done counting %d objects.\n", nr_objects);
1626         sorted_by_sha = create_final_object_list();
1627         if (non_empty && !nr_result)
1628                 return 0;
1629
1630         SHA1_Init(&ctx);
1631         list = sorted_by_sha;
1632         for (i = 0; i < nr_result; i++) {
1633                 struct object_entry *entry = *list++;
1634                 SHA1_Update(&ctx, entry->sha1, 20);
1635         }
1636         SHA1_Final(object_list_sha1, &ctx);
1637         if (progress && (nr_objects != nr_result))
1638                 fprintf(stderr, "Result has %d objects.\n", nr_result);
1639
1640         if (reuse_cached_pack(object_list_sha1))
1641                 ;
1642         else {
1643                 if (nr_result)
1644                         prepare_pack(window, depth);
1645                 if (progress && pack_to_stdout) {
1646                         /* the other end usually displays progress itself */
1647                         struct itimerval v = {{0,},};
1648                         setitimer(ITIMER_REAL, &v, NULL);
1649                         signal(SIGALRM, SIG_IGN );
1650                         progress_update = 0;
1651                 }
1652                 write_pack_file();
1653                 if (!pack_to_stdout) {
1654                         write_index_file();
1655                         puts(sha1_to_hex(object_list_sha1));
1656                 }
1657         }
1658         if (progress)
1659                 fprintf(stderr, "Total %d, written %d (delta %d), reused %d (delta %d)\n",
1660                         nr_result, written, written_delta, reused, reused_delta);
1661         return 0;
1662 }