?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
git-send-email: Add --thread option
[git/aroben.git] / builtin-pack-objects.c
blob3d396ca37ac1356c7974aaaf34af39bcd0cf6bae
1 #include "builtin.h"
2 #include "cache.h"
3 #include "attr.h"
4 #include "object.h"
5 #include "blob.h"
6 #include "commit.h"
7 #include "tag.h"
8 #include "tree.h"
9 #include "delta.h"
10 #include "pack.h"
11 #include "csum-file.h"
12 #include "tree-walk.h"
13 #include "diff.h"
14 #include "revision.h"
15 #include "list-objects.h"
16 #include "progress.h"
17
18 static const char pack_usage[] = "\
19 git-pack-objects [{ -q | --progress | --all-progress }] [--max-pack-size=N] \n\
20 [--local] [--incremental] [--window=N] [--depth=N] \n\
21 [--no-reuse-delta] [--no-reuse-object] [--delta-base-offset] \n\
22 [--non-empty] [--revs [--unpacked | --all]*] [--reflog] \n\
23 [--stdout | base-name] [<ref-list | <object-list]";
24
25 struct object_entry {
26 struct pack_idx_entry idx;
27 unsigned long size; /* uncompressed size */
28
29 unsigned int hash; /* name hint hash */
30 unsigned int depth; /* delta depth */
31 struct packed_git *in_pack; /* already in pack */
32 off_t in_pack_offset;
33 struct object_entry *delta; /* delta base object */
34 struct object_entry *delta_child; /* deltified objects who bases me */
35 struct object_entry *delta_sibling; /* other deltified objects who
36 * uses the same base as me
37 */
38 void *delta_data; /* cached delta (uncompressed) */
39 unsigned long delta_size; /* delta data size (uncompressed) */
40 enum object_type type;
41 enum object_type in_pack_type; /* could be delta */
42 unsigned char in_pack_header_size;
43 unsigned char preferred_base; /* we do not pack this, but is available
44 * to be used as the base object to delta
45 * objects against.
46 */
47 unsigned char no_try_delta;
48 };
49
50 /*
51 * Objects we are going to pack are collected in objects array (dynamically
52 * expanded). nr_objects & nr_alloc controls this array. They are stored
53 * in the order we see -- typically rev-list --objects order that gives us
54 * nice "minimum seek" order.
55 */
56 static struct object_entry *objects;
57 static struct object_entry **written_list;
58 static uint32_t nr_objects, nr_alloc, nr_result, nr_written;
59
60 static int non_empty;
61 static int no_reuse_delta, no_reuse_object;
62 static int local;
63 static int incremental;
64 static int allow_ofs_delta;
65 static const char *pack_tmp_name, *idx_tmp_name;
66 static char tmpname[PATH_MAX];
67 static const char *base_name;
68 static int progress = 1;
69 static int window = 10;
70 static uint32_t pack_size_limit;
71 static int depth = 50;
72 static int pack_to_stdout;
73 static int num_preferred_base;
74 static struct progress progress_state;
75 static int pack_compression_level = Z_DEFAULT_COMPRESSION;
76 static int pack_compression_seen;
77
78 static unsigned long delta_cache_size = 0;
79 static unsigned long max_delta_cache_size = 0;
80 static unsigned long cache_max_small_delta_size = 1000;
81
82 /*
83 * The object names in objects array are hashed with this hashtable,
84 * to help looking up the entry by object name.
85 * This hashtable is built after all the objects are seen.
86 */
87 static int *object_ix;
88 static int object_ix_hashsz;
89
90 /*
91 * Pack index for existing packs give us easy access to the offsets into
92 * corresponding pack file where each object's data starts, but the entries
93 * do not store the size of the compressed representation (uncompressed
94 * size is easily available by examining the pack entry header). It is
95 * also rather expensive to find the sha1 for an object given its offset.
96 *
97 * We build a hashtable of existing packs (pack_revindex), and keep reverse
98 * index here -- pack index file is sorted by object name mapping to offset;
99 * this pack_revindex[].revindex array is a list of offset/index_nr pairs
100 * ordered by offset, so if you know the offset of an object, next offset
101 * is where its packed representation ends and the index_nr can be used to
102 * get the object sha1 from the main index.
103 */
104 struct revindex_entry {
105 off_t offset;
106 unsigned int nr;
107 };
108 struct pack_revindex {
109 struct packed_git *p;
110 struct revindex_entry *revindex;
111 };
112 static struct pack_revindex *pack_revindex;
113 static int pack_revindex_hashsz;
114
115 /*
116 * stats
117 */
118 static uint32_t written, written_delta;
119 static uint32_t reused, reused_delta;
120
121 static int pack_revindex_ix(struct packed_git *p)
122 {
123 unsigned long ui = (unsigned long)p;
124 int i;
125
126 ui = ui ^ (ui >> 16); /* defeat structure alignment */
127 i = (int)(ui % pack_revindex_hashsz);
128 while (pack_revindex[i].p) {
129 if (pack_revindex[i].p == p)
130 return i;
131 if (++i == pack_revindex_hashsz)
132 i = 0;
133 }
134 return -1 - i;
135 }
136
137 static void prepare_pack_ix(void)
138 {
139 int num;
140 struct packed_git *p;
141 for (num = 0, p = packed_git; p; p = p->next)
142 num++;
143 if (!num)
144 return;
145 pack_revindex_hashsz = num * 11;
146 pack_revindex = xcalloc(sizeof(*pack_revindex), pack_revindex_hashsz);
147 for (p = packed_git; p; p = p->next) {
148 num = pack_revindex_ix(p);
149 num = - 1 - num;
150 pack_revindex[num].p = p;
151 }
152 /* revindex elements are lazily initialized */
153 }
154
155 static int cmp_offset(const void *a_, const void *b_)
156 {
157 const struct revindex_entry *a = a_;
158 const struct revindex_entry *b = b_;
159 return (a->offset < b->offset) ? -1 : (a->offset > b->offset) ? 1 : 0;
160 }
161
162 /*
163 * Ordered list of offsets of objects in the pack.
164 */
165 static void prepare_pack_revindex(struct pack_revindex *rix)
166 {
167 struct packed_git *p = rix->p;
168 int num_ent = p->num_objects;
169 int i;
170 const char *index = p->index_data;
171
172 rix->revindex = xmalloc(sizeof(*rix->revindex) * (num_ent + 1));
173 index += 4 * 256;
174
175 if (p->index_version > 1) {
176 const uint32_t *off_32 =
177 (uint32_t *)(index + 8 + p->num_objects * (20 + 4));
178 const uint32_t *off_64 = off_32 + p->num_objects;
179 for (i = 0; i < num_ent; i++) {
180 uint32_t off = ntohl(*off_32++);
181 if (!(off & 0x80000000)) {
182 rix->revindex[i].offset = off;
183 } else {
184 rix->revindex[i].offset =
185 ((uint64_t)ntohl(*off_64++)) << 32;
186 rix->revindex[i].offset |=
187 ntohl(*off_64++);
188 }
189 rix->revindex[i].nr = i;
190 }
191 } else {
192 for (i = 0; i < num_ent; i++) {
193 uint32_t hl = *((uint32_t *)(index + 24 * i));
194 rix->revindex[i].offset = ntohl(hl);
195 rix->revindex[i].nr = i;
196 }
197 }
198
199 /* This knows the pack format -- the 20-byte trailer
200 * follows immediately after the last object data.
201 */
202 rix->revindex[num_ent].offset = p->pack_size - 20;
203 rix->revindex[num_ent].nr = -1;
204 qsort(rix->revindex, num_ent, sizeof(*rix->revindex), cmp_offset);
205 }
206
207 static struct revindex_entry * find_packed_object(struct packed_git *p,
208 off_t ofs)
209 {
210 int num;
211 int lo, hi;
212 struct pack_revindex *rix;
213 struct revindex_entry *revindex;
214 num = pack_revindex_ix(p);
215 if (num < 0)
216 die("internal error: pack revindex uninitialized");
217 rix = &pack_revindex[num];
218 if (!rix->revindex)
219 prepare_pack_revindex(rix);
220 revindex = rix->revindex;
221 lo = 0;
222 hi = p->num_objects + 1;
223 do {
224 int mi = (lo + hi) / 2;
225 if (revindex[mi].offset == ofs) {
226 return revindex + mi;
227 }
228 else if (ofs < revindex[mi].offset)
229 hi = mi;
230 else
231 lo = mi + 1;
232 } while (lo < hi);
233 die("internal error: pack revindex corrupt");
234 }
235
236 static const unsigned char *find_packed_object_name(struct packed_git *p,
237 off_t ofs)
238 {
239 struct revindex_entry *entry = find_packed_object(p, ofs);
240 return nth_packed_object_sha1(p, entry->nr);
241 }
242
243 static void *delta_against(void *buf, unsigned long size, struct object_entry *entry)
244 {
245 unsigned long othersize, delta_size;
246 enum object_type type;
247 void *otherbuf = read_sha1_file(entry->delta->idx.sha1, &type, &othersize);
248 void *delta_buf;
249
250 if (!otherbuf)
251 die("unable to read %s", sha1_to_hex(entry->delta->idx.sha1));
252 delta_buf = diff_delta(otherbuf, othersize,
253 buf, size, &delta_size, 0);
254 if (!delta_buf || delta_size != entry->delta_size)
255 die("delta size changed");
256 free(buf);
257 free(otherbuf);
258 return delta_buf;
259 }
260
261 /*
262 * The per-object header is a pretty dense thing, which is
263 * - first byte: low four bits are "size", then three bits of "type",
264 * and the high bit is "size continues".
265 * - each byte afterwards: low seven bits are size continuation,
266 * with the high bit being "size continues"
267 */
268 static int encode_header(enum object_type type, unsigned long size, unsigned char *hdr)
269 {
270 int n = 1;
271 unsigned char c;
272
273 if (type < OBJ_COMMIT || type > OBJ_REF_DELTA)
274 die("bad type %d", type);
275
276 c = (type << 4) | (size & 15);
277 size >>= 4;
278 while (size) {
279 *hdr++ = c | 0x80;
280 c = size & 0x7f;
281 size >>= 7;
282 n++;
283 }
284 *hdr = c;
285 return n;
286 }
287
288 /*
289 * we are going to reuse the existing object data as is. make
290 * sure it is not corrupt.
291 */
292 static int check_pack_inflate(struct packed_git *p,
293 struct pack_window **w_curs,
294 off_t offset,
295 off_t len,
296 unsigned long expect)
297 {
298 z_stream stream;
299 unsigned char fakebuf[4096], *in;
300 int st;
301
302 memset(&stream, 0, sizeof(stream));
303 inflateInit(&stream);
304 do {
305 in = use_pack(p, w_curs, offset, &stream.avail_in);
306 stream.next_in = in;
307 stream.next_out = fakebuf;
308 stream.avail_out = sizeof(fakebuf);
309 st = inflate(&stream, Z_FINISH);
310 offset += stream.next_in - in;
311 } while (st == Z_OK || st == Z_BUF_ERROR);
312 inflateEnd(&stream);
313 return (st == Z_STREAM_END &&
314 stream.total_out == expect &&
315 stream.total_in == len) ? 0 : -1;
316 }
317
318 static int check_pack_crc(struct packed_git *p, struct pack_window **w_curs,
319 off_t offset, off_t len, unsigned int nr)
320 {
321 const uint32_t *index_crc;
322 uint32_t data_crc = crc32(0, Z_NULL, 0);
323
324 do {
325 unsigned int avail;
326 void *data = use_pack(p, w_curs, offset, &avail);
327 if (avail > len)
328 avail = len;
329 data_crc = crc32(data_crc, data, avail);
330 offset += avail;
331 len -= avail;
332 } while (len);
333
334 index_crc = p->index_data;
335 index_crc += 2 + 256 + p->num_objects * (20/4) + nr;
336
337 return data_crc != ntohl(*index_crc);
338 }
339
340 static void copy_pack_data(struct sha1file *f,
341 struct packed_git *p,
342 struct pack_window **w_curs,
343 off_t offset,
344 off_t len)
345 {
346 unsigned char *in;
347 unsigned int avail;
348
349 while (len) {
350 in = use_pack(p, w_curs, offset, &avail);
351 if (avail > len)
352 avail = (unsigned int)len;
353 sha1write(f, in, avail);
354 offset += avail;
355 len -= avail;
356 }
357 }
358
359 static unsigned long write_object(struct sha1file *f,
360 struct object_entry *entry,
361 off_t write_offset)
362 {
363 unsigned long size;
364 enum object_type type;
365 void *buf;
366 unsigned char header[10];
367 unsigned char dheader[10];
368 unsigned hdrlen;
369 off_t datalen;
370 enum object_type obj_type;
371 int to_reuse = 0;
372 /* write limit if limited packsize and not first object */
373 unsigned long limit = pack_size_limit && nr_written ?
374 pack_size_limit - write_offset : 0;
375 /* no if no delta */
376 int usable_delta = !entry->delta ? 0 :
377 /* yes if unlimited packfile */
378 !pack_size_limit ? 1 :
379 /* no if base written to previous pack */
380 entry->delta->idx.offset == (off_t)-1 ? 0 :
381 /* otherwise double-check written to this
382 * pack, like we do below
383 */
384 entry->delta->idx.offset ? 1 : 0;
385
386 if (!pack_to_stdout)
387 crc32_begin(f);
388
389 obj_type = entry->type;
390 if (no_reuse_object)
391 to_reuse = 0; /* explicit */
392 else if (!entry->in_pack)
393 to_reuse = 0; /* can't reuse what we don't have */
394 else if (obj_type == OBJ_REF_DELTA || obj_type == OBJ_OFS_DELTA)
395 /* check_object() decided it for us ... */
396 to_reuse = usable_delta;
397 /* ... but pack split may override that */
398 else if (obj_type != entry->in_pack_type)
399 to_reuse = 0; /* pack has delta which is unusable */
400 else if (entry->delta)
401 to_reuse = 0; /* we want to pack afresh */
402 else
403 to_reuse = 1; /* we have it in-pack undeltified,
404 * and we do not need to deltify it.
405 */
406
407 if (!to_reuse) {
408 z_stream stream;
409 unsigned long maxsize;
410 void *out;
411 if (!usable_delta) {
412 buf = read_sha1_file(entry->idx.sha1, &obj_type, &size);
413 if (!buf)
414 die("unable to read %s", sha1_to_hex(entry->idx.sha1));
415 } else if (entry->delta_data) {
416 size = entry->delta_size;
417 buf = entry->delta_data;
418 entry->delta_data = NULL;
419 obj_type = (allow_ofs_delta && entry->delta->idx.offset) ?
420 OBJ_OFS_DELTA : OBJ_REF_DELTA;
421 } else {
422 buf = read_sha1_file(entry->idx.sha1, &type, &size);
423 if (!buf)
424 die("unable to read %s", sha1_to_hex(entry->idx.sha1));
425 buf = delta_against(buf, size, entry);
426 size = entry->delta_size;
427 obj_type = (allow_ofs_delta && entry->delta->idx.offset) ?
428 OBJ_OFS_DELTA : OBJ_REF_DELTA;
429 }
430 /* compress the data to store and put compressed length in datalen */
431 memset(&stream, 0, sizeof(stream));
432 deflateInit(&stream, pack_compression_level);
433 maxsize = deflateBound(&stream, size);
434 out = xmalloc(maxsize);
435 /* Compress it */
436 stream.next_in = buf;
437 stream.avail_in = size;
438 stream.next_out = out;
439 stream.avail_out = maxsize;
440 while (deflate(&stream, Z_FINISH) == Z_OK)
441 /* nothing */;
442 deflateEnd(&stream);
443 datalen = stream.total_out;
444 deflateEnd(&stream);
445 /*
446 * The object header is a byte of 'type' followed by zero or
447 * more bytes of length.
448 */
449 hdrlen = encode_header(obj_type, size, header);
450
451 if (obj_type == OBJ_OFS_DELTA) {
452 /*
453 * Deltas with relative base contain an additional
454 * encoding of the relative offset for the delta
455 * base from this object's position in the pack.
456 */
457 off_t ofs = entry->idx.offset - entry->delta->idx.offset;
458 unsigned pos = sizeof(dheader) - 1;
459 dheader[pos] = ofs & 127;
460 while (ofs >>= 7)
461 dheader[--pos] = 128 | (--ofs & 127);
462 if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit) {
463 free(out);
464 free(buf);
465 return 0;
466 }
467 sha1write(f, header, hdrlen);
468 sha1write(f, dheader + pos, sizeof(dheader) - pos);
469 hdrlen += sizeof(dheader) - pos;
470 } else if (obj_type == OBJ_REF_DELTA) {
471 /*
472 * Deltas with a base reference contain
473 * an additional 20 bytes for the base sha1.
474 */
475 if (limit && hdrlen + 20 + datalen + 20 >= limit) {
476 free(out);
477 free(buf);
478 return 0;
479 }
480 sha1write(f, header, hdrlen);
481 sha1write(f, entry->delta->idx.sha1, 20);
482 hdrlen += 20;
483 } else {
484 if (limit && hdrlen + datalen + 20 >= limit) {
485 free(out);
486 free(buf);
487 return 0;
488 }
489 sha1write(f, header, hdrlen);
490 }
491 sha1write(f, out, datalen);
492 free(out);
493 free(buf);
494 }
495 else {
496 struct packed_git *p = entry->in_pack;
497 struct pack_window *w_curs = NULL;
498 struct revindex_entry *revidx;
499 off_t offset;
500
501 if (entry->delta) {
502 obj_type = (allow_ofs_delta && entry->delta->idx.offset) ?
503 OBJ_OFS_DELTA : OBJ_REF_DELTA;
504 reused_delta++;
505 }
506 hdrlen = encode_header(obj_type, entry->size, header);
507 offset = entry->in_pack_offset;
508 revidx = find_packed_object(p, offset);
509 datalen = revidx[1].offset - offset;
510 if (!pack_to_stdout && p->index_version > 1 &&
511 check_pack_crc(p, &w_curs, offset, datalen, revidx->nr))
512 die("bad packed object CRC for %s", sha1_to_hex(entry->idx.sha1));
513 offset += entry->in_pack_header_size;
514 datalen -= entry->in_pack_header_size;
515 if (obj_type == OBJ_OFS_DELTA) {
516 off_t ofs = entry->idx.offset - entry->delta->idx.offset;
517 unsigned pos = sizeof(dheader) - 1;
518 dheader[pos] = ofs & 127;
519 while (ofs >>= 7)
520 dheader[--pos] = 128 | (--ofs & 127);
521 if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit)
522 return 0;
523 sha1write(f, header, hdrlen);
524 sha1write(f, dheader + pos, sizeof(dheader) - pos);
525 hdrlen += sizeof(dheader) - pos;
526 } else if (obj_type == OBJ_REF_DELTA) {
527 if (limit && hdrlen + 20 + datalen + 20 >= limit)
528 return 0;
529 sha1write(f, header, hdrlen);
530 sha1write(f, entry->delta->idx.sha1, 20);
531 hdrlen += 20;
532 } else {
533 if (limit && hdrlen + datalen + 20 >= limit)
534 return 0;
535 sha1write(f, header, hdrlen);
536 }
537
538 if (!pack_to_stdout && p->index_version == 1 &&
539 check_pack_inflate(p, &w_curs, offset, datalen, entry->size))
540 die("corrupt packed object for %s", sha1_to_hex(entry->idx.sha1));
541 copy_pack_data(f, p, &w_curs, offset, datalen);
542 unuse_pack(&w_curs);
543 reused++;
544 }
545 if (usable_delta)
546 written_delta++;
547 written++;
548 if (!pack_to_stdout)
549 entry->idx.crc32 = crc32_end(f);
550 return hdrlen + datalen;
551 }
552
553 static off_t write_one(struct sha1file *f,
554 struct object_entry *e,
555 off_t offset)
556 {
557 unsigned long size;
558
559 /* offset is non zero if object is written already. */
560 if (e->idx.offset || e->preferred_base)
561 return offset;
562
563 /* if we are deltified, write out base object first. */
564 if (e->delta) {
565 offset = write_one(f, e->delta, offset);
566 if (!offset)
567 return 0;
568 }
569
570 e->idx.offset = offset;
571 size = write_object(f, e, offset);
572 if (!size) {
573 e->idx.offset = 0;
574 return 0;
575 }
576 written_list[nr_written++] = e;
577
578 /* make sure off_t is sufficiently large not to wrap */
579 if (offset > offset + size)
580 die("pack too large for current definition of off_t");
581 return offset + size;
582 }
583
584 static int open_object_dir_tmp(const char *path)
585 {
586 snprintf(tmpname, sizeof(tmpname), "%s/%s", get_object_directory(), path);
587 return mkstemp(tmpname);
588 }
589
590 /* forward declaration for write_pack_file */
591 static int adjust_perm(const char *path, mode_t mode);
592
593 static void write_pack_file(void)
594 {
595 uint32_t i = 0, j;
596 struct sha1file *f;
597 off_t offset, offset_one, last_obj_offset = 0;
598 struct pack_header hdr;
599 int do_progress = progress >> pack_to_stdout;
600 uint32_t nr_remaining = nr_result;
601
602 if (do_progress)
603 start_progress(&progress_state, "Writing %u objects...", "", nr_result);
604 written_list = xmalloc(nr_objects * sizeof(struct object_entry *));
605
606 do {
607 unsigned char sha1[20];
608
609 if (pack_to_stdout) {
610 f = sha1fd(1, "<stdout>");
611 } else {
612 int fd = open_object_dir_tmp("tmp_pack_XXXXXX");
613 if (fd < 0)
614 die("unable to create %s: %s\n", tmpname, strerror(errno));
615 pack_tmp_name = xstrdup(tmpname);
616 f = sha1fd(fd, pack_tmp_name);
617 }
618
619 hdr.hdr_signature = htonl(PACK_SIGNATURE);
620 hdr.hdr_version = htonl(PACK_VERSION);
621 hdr.hdr_entries = htonl(nr_remaining);
622 sha1write(f, &hdr, sizeof(hdr));
623 offset = sizeof(hdr);
624 nr_written = 0;
625 for (; i < nr_objects; i++) {
626 last_obj_offset = offset;
627 offset_one = write_one(f, objects + i, offset);
628 if (!offset_one)
629 break;
630 offset = offset_one;
631 if (do_progress)
632 display_progress(&progress_state, written);
633 }
634
635 /*
636 * Did we write the wrong # entries in the header?
637 * If so, rewrite it like in fast-import
638 */
639 if (pack_to_stdout || nr_written == nr_remaining) {
640 sha1close(f, sha1, 1);
641 } else {
642 sha1close(f, sha1, 0);
643 fixup_pack_header_footer(f->fd, sha1, pack_tmp_name, nr_written);
644 close(f->fd);
645 }
646
647 if (!pack_to_stdout) {
648 mode_t mode = umask(0);
649
650 umask(mode);
651 mode = 0444 & ~mode;
652
653 idx_tmp_name = write_idx_file(NULL,
654 (struct pack_idx_entry **) written_list, nr_written, sha1);
655 snprintf(tmpname, sizeof(tmpname), "%s-%s.pack",
656 base_name, sha1_to_hex(sha1));
657 if (adjust_perm(pack_tmp_name, mode))
658 die("unable to make temporary pack file readable: %s",
659 strerror(errno));
660 if (rename(pack_tmp_name, tmpname))
661 die("unable to rename temporary pack file: %s",
662 strerror(errno));
663 snprintf(tmpname, sizeof(tmpname), "%s-%s.idx",
664 base_name, sha1_to_hex(sha1));
665 if (adjust_perm(idx_tmp_name, mode))
666 die("unable to make temporary index file readable: %s",
667 strerror(errno));
668 if (rename(idx_tmp_name, tmpname))
669 die("unable to rename temporary index file: %s",
670 strerror(errno));
671 puts(sha1_to_hex(sha1));
672 }
673
674 /* mark written objects as written to previous pack */
675 for (j = 0; j < nr_written; j++) {
676 written_list[j]->idx.offset = (off_t)-1;
677 }
678 nr_remaining -= nr_written;
679 } while (nr_remaining && i < nr_objects);
680
681 free(written_list);
682 if (do_progress)
683 stop_progress(&progress_state);
684 if (written != nr_result)
685 die("wrote %u objects while expecting %u", written, nr_result);
686 /*
687 * We have scanned through [0 ... i). Since we have written
688 * the correct number of objects, the remaining [i ... nr_objects)
689 * items must be either already written (due to out-of-order delta base)
690 * or a preferred base. Count those which are neither and complain if any.
691 */
692 for (j = 0; i < nr_objects; i++) {
693 struct object_entry *e = objects + i;
694 j += !e->idx.offset && !e->preferred_base;
695 }
696 if (j)
697 die("wrote %u objects as expected but %u unwritten", written, j);
698 }
699
700 static int locate_object_entry_hash(const unsigned char *sha1)
701 {
702 int i;
703 unsigned int ui;
704 memcpy(&ui, sha1, sizeof(unsigned int));
705 i = ui % object_ix_hashsz;
706 while (0 < object_ix[i]) {
707 if (!hashcmp(sha1, objects[object_ix[i] - 1].idx.sha1))
708 return i;
709 if (++i == object_ix_hashsz)
710 i = 0;
711 }
712 return -1 - i;
713 }
714
715 static struct object_entry *locate_object_entry(const unsigned char *sha1)
716 {
717 int i;
718
719 if (!object_ix_hashsz)
720 return NULL;
721
722 i = locate_object_entry_hash(sha1);
723 if (0 <= i)
724 return &objects[object_ix[i]-1];
725 return NULL;
726 }
727
728 static void rehash_objects(void)
729 {
730 uint32_t i;
731 struct object_entry *oe;
732
733 object_ix_hashsz = nr_objects * 3;
734 if (object_ix_hashsz < 1024)
735 object_ix_hashsz = 1024;
736 object_ix = xrealloc(object_ix, sizeof(int) * object_ix_hashsz);
737 memset(object_ix, 0, sizeof(int) * object_ix_hashsz);
738 for (i = 0, oe = objects; i < nr_objects; i++, oe++) {
739 int ix = locate_object_entry_hash(oe->idx.sha1);
740 if (0 <= ix)
741 continue;
742 ix = -1 - ix;
743 object_ix[ix] = i + 1;
744 }
745 }
746
747 static unsigned name_hash(const char *name)
748 {
749 unsigned char c;
750 unsigned hash = 0;
751
752 if (!name)
753 return 0;
754
755 /*
756 * This effectively just creates a sortable number from the
757 * last sixteen non-whitespace characters. Last characters
758 * count "most", so things that end in ".c" sort together.
759 */
760 while ((c = *name++) != 0) {
761 if (isspace(c))
762 continue;
763 hash = (hash >> 2) + (c << 24);
764 }
765 return hash;
766 }
767
768 static void setup_delta_attr_check(struct git_attr_check *check)
769 {
770 static struct git_attr *attr_delta;
771
772 if (!attr_delta)
773 attr_delta = git_attr("delta", 5);
774
775 check[0].attr = attr_delta;
776 }
777
778 static int no_try_delta(const char *path)
779 {
780 struct git_attr_check check[1];
781
782 setup_delta_attr_check(check);
783 if (git_checkattr(path, ARRAY_SIZE(check), check))
784 return 0;
785 if (ATTR_FALSE(check->value))
786 return 1;
787 return 0;
788 }
789
790 static int add_object_entry(const unsigned char *sha1, enum object_type type,
791 const char *name, int exclude)
792 {
793 struct object_entry *entry;
794 struct packed_git *p, *found_pack = NULL;
795 off_t found_offset = 0;
796 int ix;
797 unsigned hash = name_hash(name);
798
799 ix = nr_objects ? locate_object_entry_hash(sha1) : -1;
800 if (ix >= 0) {
801 if (exclude) {
802 entry = objects + object_ix[ix] - 1;
803 if (!entry->preferred_base)
804 nr_result--;
805 entry->preferred_base = 1;
806 }
807 return 0;
808 }
809
810 for (p = packed_git; p; p = p->next) {
811 off_t offset = find_pack_entry_one(sha1, p);
812 if (offset) {
813 if (!found_pack) {
814 found_offset = offset;
815 found_pack = p;
816 }
817 if (exclude)
818 break;
819 if (incremental)
820 return 0;
821 if (local && !p->pack_local)
822 return 0;
823 }
824 }
825
826 if (nr_objects >= nr_alloc) {
827 nr_alloc = (nr_alloc + 1024) * 3 / 2;
828 objects = xrealloc(objects, nr_alloc * sizeof(*entry));
829 }
830
831 entry = objects + nr_objects++;
832 memset(entry, 0, sizeof(*entry));
833 hashcpy(entry->idx.sha1, sha1);
834 entry->hash = hash;
835 if (type)
836 entry->type = type;
837 if (exclude)
838 entry->preferred_base = 1;
839 else
840 nr_result++;
841 if (found_pack) {
842 entry->in_pack = found_pack;
843 entry->in_pack_offset = found_offset;
844 }
845
846 if (object_ix_hashsz * 3 <= nr_objects * 4)
847 rehash_objects();
848 else
849 object_ix[-1 - ix] = nr_objects;
850
851 if (progress)
852 display_progress(&progress_state, nr_objects);
853
854 if (name && no_try_delta(name))
855 entry->no_try_delta = 1;
856
857 return 1;
858 }
859
860 struct pbase_tree_cache {
861 unsigned char sha1[20];
862 int ref;
863 int temporary;
864 void *tree_data;
865 unsigned long tree_size;
866 };
867
868 static struct pbase_tree_cache *(pbase_tree_cache[256]);
869 static int pbase_tree_cache_ix(const unsigned char *sha1)
870 {
871 return sha1[0] % ARRAY_SIZE(pbase_tree_cache);
872 }
873 static int pbase_tree_cache_ix_incr(int ix)
874 {
875 return (ix+1) % ARRAY_SIZE(pbase_tree_cache);
876 }
877
878 static struct pbase_tree {
879 struct pbase_tree *next;
880 /* This is a phony "cache" entry; we are not
881 * going to evict it nor find it through _get()
882 * mechanism -- this is for the toplevel node that
883 * would almost always change with any commit.
884 */
885 struct pbase_tree_cache pcache;
886 } *pbase_tree;
887
888 static struct pbase_tree_cache *pbase_tree_get(const unsigned char *sha1)
889 {
890 struct pbase_tree_cache *ent, *nent;
891 void *data;
892 unsigned long size;
893 enum object_type type;
894 int neigh;
895 int my_ix = pbase_tree_cache_ix(sha1);
896 int available_ix = -1;
897
898 /* pbase-tree-cache acts as a limited hashtable.
899 * your object will be found at your index or within a few
900 * slots after that slot if it is cached.
901 */
902 for (neigh = 0; neigh < 8; neigh++) {
903 ent = pbase_tree_cache[my_ix];
904 if (ent && !hashcmp(ent->sha1, sha1)) {
905 ent->ref++;
906 return ent;
907 }
908 else if (((available_ix < 0) && (!ent || !ent->ref)) ||
909 ((0 <= available_ix) &&
910 (!ent && pbase_tree_cache[available_ix])))
911 available_ix = my_ix;
912 if (!ent)
913 break;
914 my_ix = pbase_tree_cache_ix_incr(my_ix);
915 }
916
917 /* Did not find one. Either we got a bogus request or
918 * we need to read and perhaps cache.
919 */
920 data = read_sha1_file(sha1, &type, &size);
921 if (!data)
922 return NULL;
923 if (type != OBJ_TREE) {
924 free(data);
925 return NULL;
926 }
927
928 /* We need to either cache or return a throwaway copy */
929
930 if (available_ix < 0)
931 ent = NULL;
932 else {
933 ent = pbase_tree_cache[available_ix];
934 my_ix = available_ix;
935 }
936
937 if (!ent) {
938 nent = xmalloc(sizeof(*nent));
939 nent->temporary = (available_ix < 0);
940 }
941 else {
942 /* evict and reuse */
943 free(ent->tree_data);
944 nent = ent;
945 }
946 hashcpy(nent->sha1, sha1);
947 nent->tree_data = data;
948 nent->tree_size = size;
949 nent->ref = 1;
950 if (!nent->temporary)
951 pbase_tree_cache[my_ix] = nent;
952 return nent;
953 }
954
955 static void pbase_tree_put(struct pbase_tree_cache *cache)
956 {
957 if (!cache->temporary) {
958 cache->ref--;
959 return;
960 }
961 free(cache->tree_data);
962 free(cache);
963 }
964
965 static int name_cmp_len(const char *name)
966 {
967 int i;
968 for (i = 0; name[i] && name[i] != '\n' && name[i] != '/'; i++)
969 ;
970 return i;
971 }
972
973 static void add_pbase_object(struct tree_desc *tree,
974 const char *name,
975 int cmplen,
976 const char *fullname)
977 {
978 struct name_entry entry;
979 int cmp;
980
981 while (tree_entry(tree,&entry)) {
982 cmp = tree_entry_len(entry.path, entry.sha1) != cmplen ? 1 :
983 memcmp(name, entry.path, cmplen);
984 if (cmp > 0)
985 continue;
986 if (cmp < 0)
987 return;
988 if (name[cmplen] != '/') {
989 add_object_entry(entry.sha1,
990 S_ISDIR(entry.mode) ? OBJ_TREE : OBJ_BLOB,
991 fullname, 1);
992 return;
993 }
994 if (S_ISDIR(entry.mode)) {
995 struct tree_desc sub;
996 struct pbase_tree_cache *tree;
997 const char *down = name+cmplen+1;
998 int downlen = name_cmp_len(down);
999
1000 tree = pbase_tree_get(entry.sha1);
1001 if (!tree)
1002 return;
1003 init_tree_desc(&sub, tree->tree_data, tree->tree_size);
1004
1005 add_pbase_object(&sub, down, downlen, fullname);
1006 pbase_tree_put(tree);
1007 }
1008 }
1009 }
1010
1011 static unsigned *done_pbase_paths;
1012 static int done_pbase_paths_num;
1013 static int done_pbase_paths_alloc;
1014 static int done_pbase_path_pos(unsigned hash)
1015 {
1016 int lo = 0;
1017 int hi = done_pbase_paths_num;
1018 while (lo < hi) {
1019 int mi = (hi + lo) / 2;
1020 if (done_pbase_paths[mi] == hash)
1021 return mi;
1022 if (done_pbase_paths[mi] < hash)
1023 hi = mi;
1024 else
1025 lo = mi + 1;
1026 }
1027 return -lo-1;
1028 }
1029
1030 static int check_pbase_path(unsigned hash)
1031 {
1032 int pos = (!done_pbase_paths) ? -1 : done_pbase_path_pos(hash);
1033 if (0 <= pos)
1034 return 1;
1035 pos = -pos - 1;
1036 if (done_pbase_paths_alloc <= done_pbase_paths_num) {
1037 done_pbase_paths_alloc = alloc_nr(done_pbase_paths_alloc);
1038 done_pbase_paths = xrealloc(done_pbase_paths,
1039 done_pbase_paths_alloc *
1040 sizeof(unsigned));
1041 }
1042 done_pbase_paths_num++;
1043 if (pos < done_pbase_paths_num)
1044 memmove(done_pbase_paths + pos + 1,
1045 done_pbase_paths + pos,
1046 (done_pbase_paths_num - pos - 1) * sizeof(unsigned));
1047 done_pbase_paths[pos] = hash;
1048 return 0;
1049 }
1050
1051 static void add_preferred_base_object(const char *name)
1052 {
1053 struct pbase_tree *it;
1054 int cmplen;
1055 unsigned hash = name_hash(name);
1056
1057 if (!num_preferred_base || check_pbase_path(hash))
1058 return;
1059
1060 cmplen = name_cmp_len(name);
1061 for (it = pbase_tree; it; it = it->next) {
1062 if (cmplen == 0) {
1063 add_object_entry(it->pcache.sha1, OBJ_TREE, NULL, 1);
1064 }
1065 else {
1066 struct tree_desc tree;
1067 init_tree_desc(&tree, it->pcache.tree_data, it->pcache.tree_size);
1068 add_pbase_object(&tree, name, cmplen, name);
1069 }
1070 }
1071 }
1072
1073 static void add_preferred_base(unsigned char *sha1)
1074 {
1075 struct pbase_tree *it;
1076 void *data;
1077 unsigned long size;
1078 unsigned char tree_sha1[20];
1079
1080 if (window <= num_preferred_base++)
1081 return;
1082
1083 data = read_object_with_reference(sha1, tree_type, &size, tree_sha1);
1084 if (!data)
1085 return;
1086
1087 for (it = pbase_tree; it; it = it->next) {
1088 if (!hashcmp(it->pcache.sha1, tree_sha1)) {
1089 free(data);
1090 return;
1091 }
1092 }
1093
1094 it = xcalloc(1, sizeof(*it));
1095 it->next = pbase_tree;
1096 pbase_tree = it;
1097
1098 hashcpy(it->pcache.sha1, tree_sha1);
1099 it->pcache.tree_data = data;
1100 it->pcache.tree_size = size;
1101 }
1102
1103 static void check_object(struct object_entry *entry)
1104 {
1105 if (entry->in_pack) {
1106 struct packed_git *p = entry->in_pack;
1107 struct pack_window *w_curs = NULL;
1108 const unsigned char *base_ref = NULL;
1109 struct object_entry *base_entry;
1110 unsigned long used, used_0;
1111 unsigned int avail;
1112 off_t ofs;
1113 unsigned char *buf, c;
1114
1115 buf = use_pack(p, &w_curs, entry->in_pack_offset, &avail);
1116
1117 /*
1118 * We want in_pack_type even if we do not reuse delta
1119 * since non-delta representations could still be reused.
1120 */
1121 used = unpack_object_header_gently(buf, avail,
1122 &entry->in_pack_type,
1123 &entry->size);
1124
1125 /*
1126 * Determine if this is a delta and if so whether we can
1127 * reuse it or not. Otherwise let's find out as cheaply as
1128 * possible what the actual type and size for this object is.
1129 */
1130 switch (entry->in_pack_type) {
1131 default:
1132 /* Not a delta hence we've already got all we need. */
1133 entry->type = entry->in_pack_type;
1134 entry->in_pack_header_size = used;
1135 unuse_pack(&w_curs);
1136 return;
1137 case OBJ_REF_DELTA:
1138 if (!no_reuse_delta && !entry->preferred_base)
1139 base_ref = use_pack(p, &w_curs,
1140 entry->in_pack_offset + used, NULL);
1141 entry->in_pack_header_size = used + 20;
1142 break;
1143 case OBJ_OFS_DELTA:
1144 buf = use_pack(p, &w_curs,
1145 entry->in_pack_offset + used, NULL);
1146 used_0 = 0;
1147 c = buf[used_0++];
1148 ofs = c & 127;
1149 while (c & 128) {
1150 ofs += 1;
1151 if (!ofs || MSB(ofs, 7))
1152 die("delta base offset overflow in pack for %s",
1153 sha1_to_hex(entry->idx.sha1));
1154 c = buf[used_0++];
1155 ofs = (ofs << 7) + (c & 127);
1156 }
1157 if (ofs >= entry->in_pack_offset)
1158 die("delta base offset out of bound for %s",
1159 sha1_to_hex(entry->idx.sha1));
1160 ofs = entry->in_pack_offset - ofs;
1161 if (!no_reuse_delta && !entry->preferred_base)
1162 base_ref = find_packed_object_name(p, ofs);
1163 entry->in_pack_header_size = used + used_0;
1164 break;
1165 }
1166
1167 if (base_ref && (base_entry = locate_object_entry(base_ref))) {
1168 /*
1169 * If base_ref was set above that means we wish to
1170 * reuse delta data, and we even found that base
1171 * in the list of objects we want to pack. Goodie!
1172 *
1173 * Depth value does not matter - find_deltas() will
1174 * never consider reused delta as the base object to
1175 * deltify other objects against, in order to avoid
1176 * circular deltas.
1177 */
1178 entry->type = entry->in_pack_type;
1179 entry->delta = base_entry;
1180 entry->delta_sibling = base_entry->delta_child;
1181 base_entry->delta_child = entry;
1182 unuse_pack(&w_curs);
1183 return;
1184 }
1185
1186 if (entry->type) {
1187 /*
1188 * This must be a delta and we already know what the
1189 * final object type is. Let's extract the actual
1190 * object size from the delta header.
1191 */
1192 entry->size = get_size_from_delta(p, &w_curs,
1193 entry->in_pack_offset + entry->in_pack_header_size);
1194 unuse_pack(&w_curs);
1195 return;
1196 }
1197
1198 /*
1199 * No choice but to fall back to the recursive delta walk
1200 * with sha1_object_info() to find about the object type
1201 * at this point...
1202 */
1203 unuse_pack(&w_curs);
1204 }
1205
1206 entry->type = sha1_object_info(entry->idx.sha1, &entry->size);
1207 if (entry->type < 0)
1208 die("unable to get type of object %s",
1209 sha1_to_hex(entry->idx.sha1));
1210 }
1211
1212 static int pack_offset_sort(const void *_a, const void *_b)
1213 {
1214 const struct object_entry *a = *(struct object_entry **)_a;
1215 const struct object_entry *b = *(struct object_entry **)_b;
1216
1217 /* avoid filesystem trashing with loose objects */
1218 if (!a->in_pack && !b->in_pack)
1219 return hashcmp(a->idx.sha1, b->idx.sha1);
1220
1221 if (a->in_pack < b->in_pack)
1222 return -1;
1223 if (a->in_pack > b->in_pack)
1224 return 1;
1225 return a->in_pack_offset < b->in_pack_offset ? -1 :
1226 (a->in_pack_offset > b->in_pack_offset);
1227 }
1228
1229 static void get_object_details(void)
1230 {
1231 uint32_t i;
1232 struct object_entry **sorted_by_offset;
1233
1234 sorted_by_offset = xcalloc(nr_objects, sizeof(struct object_entry *));
1235 for (i = 0; i < nr_objects; i++)
1236 sorted_by_offset[i] = objects + i;
1237 qsort(sorted_by_offset, nr_objects, sizeof(*sorted_by_offset), pack_offset_sort);
1238
1239 prepare_pack_ix();
1240 for (i = 0; i < nr_objects; i++)
1241 check_object(sorted_by_offset[i]);
1242 free(sorted_by_offset);
1243 }
1244
1245 static int type_size_sort(const void *_a, const void *_b)
1246 {
1247 const struct object_entry *a = *(struct object_entry **)_a;
1248 const struct object_entry *b = *(struct object_entry **)_b;
1249
1250 if (a->type < b->type)
1251 return -1;
1252 if (a->type > b->type)
1253 return 1;
1254 if (a->hash < b->hash)
1255 return -1;
1256 if (a->hash > b->hash)
1257 return 1;
1258 if (a->preferred_base < b->preferred_base)
1259 return -1;
1260 if (a->preferred_base > b->preferred_base)
1261 return 1;
1262 if (a->size < b->size)
1263 return -1;
1264 if (a->size > b->size)
1265 return 1;
1266 return a > b ? -1 : (a < b); /* newest last */
1267 }
1268
1269 struct unpacked {
1270 struct object_entry *entry;
1271 void *data;
1272 struct delta_index *index;
1273 };
1274
1275 static int delta_cacheable(struct unpacked *trg, struct unpacked *src,
1276 unsigned long src_size, unsigned long trg_size,
1277 unsigned long delta_size)
1278 {
1279 if (max_delta_cache_size && delta_cache_size + delta_size > max_delta_cache_size)
1280 return 0;
1281
1282 if (delta_size < cache_max_small_delta_size)
1283 return 1;
1284
1285 /* cache delta, if objects are large enough compared to delta size */
1286 if ((src_size >> 20) + (trg_size >> 21) > (delta_size >> 10))
1287 return 1;
1288
1289 return 0;
1290 }
1291
1292 /*
1293 * We search for deltas _backwards_ in a list sorted by type and
1294 * by size, so that we see progressively smaller and smaller files.
1295 * That's because we prefer deltas to be from the bigger file
1296 * to the smaller - deletes are potentially cheaper, but perhaps
1297 * more importantly, the bigger file is likely the more recent
1298 * one.
1299 */
1300 static int try_delta(struct unpacked *trg, struct unpacked *src,
1301 unsigned max_depth)
1302 {
1303 struct object_entry *trg_entry = trg->entry;
1304 struct object_entry *src_entry = src->entry;
1305 unsigned long trg_size, src_size, delta_size, sizediff, max_size, sz;
1306 enum object_type type;
1307 void *delta_buf;
1308
1309 /* Don't bother doing diffs between different types */
1310 if (trg_entry->type != src_entry->type)
1311 return -1;
1312
1313 /* We do not compute delta to *create* objects we are not
1314 * going to pack.
1315 */
1316 if (trg_entry->preferred_base)
1317 return -1;
1318
1319 /*
1320 * We do not bother to try a delta that we discarded
1321 * on an earlier try, but only when reusing delta data.
1322 */
1323 if (!no_reuse_delta && trg_entry->in_pack &&
1324 trg_entry->in_pack == src_entry->in_pack &&
1325 trg_entry->in_pack_type != OBJ_REF_DELTA &&
1326 trg_entry->in_pack_type != OBJ_OFS_DELTA)
1327 return 0;
1328
1329 /* Let's not bust the allowed depth. */
1330 if (src_entry->depth >= max_depth)
1331 return 0;
1332
1333 /* Now some size filtering heuristics. */
1334 trg_size = trg_entry->size;
1335 max_size = trg_size/2 - 20;
1336 max_size = max_size * (max_depth - src_entry->depth) / max_depth;
1337 if (max_size == 0)
1338 return 0;
1339 if (trg_entry->delta && trg_entry->delta_size <= max_size)
1340 max_size = trg_entry->delta_size-1;
1341 src_size = src_entry->size;
1342 sizediff = src_size < trg_size ? trg_size - src_size : 0;
1343 if (sizediff >= max_size)
1344 return 0;
1345
1346 /* Load data if not already done */
1347 if (!trg->data) {
1348 trg->data = read_sha1_file(trg_entry->idx.sha1, &type, &sz);
1349 if (sz != trg_size)
1350 die("object %s inconsistent object length (%lu vs %lu)",
1351 sha1_to_hex(trg_entry->idx.sha1), sz, trg_size);
1352 }
1353 if (!src->data) {
1354 src->data = read_sha1_file(src_entry->idx.sha1, &type, &sz);
1355 if (sz != src_size)
1356 die("object %s inconsistent object length (%lu vs %lu)",
1357 sha1_to_hex(src_entry->idx.sha1), sz, src_size);
1358 }
1359 if (!src->index) {
1360 src->index = create_delta_index(src->data, src_size);
1361 if (!src->index) {
1362 static int warned = 0;
1363 if (!warned++)
1364 warning("suboptimal pack - out of memory");
1365 return 0;
1366 }
1367 }
1368
1369 delta_buf = create_delta(src->index, trg->data, trg_size, &delta_size, max_size);
1370 if (!delta_buf)
1371 return 0;
1372
1373 if (trg_entry->delta_data) {
1374 delta_cache_size -= trg_entry->delta_size;
1375 free(trg_entry->delta_data);
1376 }
1377 trg_entry->delta_data = 0;
1378 trg_entry->delta = src_entry;
1379 trg_entry->delta_size = delta_size;
1380 trg_entry->depth = src_entry->depth + 1;
1381
1382 if (delta_cacheable(src, trg, src_size, trg_size, delta_size)) {
1383 trg_entry->delta_data = xrealloc(delta_buf, delta_size);
1384 delta_cache_size += trg_entry->delta_size;
1385 } else
1386 free(delta_buf);
1387 return 1;
1388 }
1389
1390 static unsigned int check_delta_limit(struct object_entry *me, unsigned int n)
1391 {
1392 struct object_entry *child = me->delta_child;
1393 unsigned int m = n;
1394 while (child) {
1395 unsigned int c = check_delta_limit(child, n + 1);
1396 if (m < c)
1397 m = c;
1398 child = child->delta_sibling;
1399 }
1400 return m;
1401 }
1402
1403 static void find_deltas(struct object_entry **list, int window, int depth)
1404 {
1405 uint32_t i = nr_objects, idx = 0, processed = 0;
1406 unsigned int array_size = window * sizeof(struct unpacked);
1407 struct unpacked *array;
1408 int max_depth;
1409
1410 if (!nr_objects)
1411 return;
1412 array = xmalloc(array_size);
1413 memset(array, 0, array_size);
1414 if (progress)
1415 start_progress(&progress_state, "Deltifying %u objects...", "", nr_result);
1416
1417 do {
1418 struct object_entry *entry = list[--i];
1419 struct unpacked *n = array + idx;
1420 int j;
1421
1422 if (!entry->preferred_base)
1423 processed++;
1424
1425 if (progress)
1426 display_progress(&progress_state, processed);
1427
1428 if (entry->delta)
1429 /* This happens if we decided to reuse existing
1430 * delta from a pack. "!no_reuse_delta &&" is implied.
1431 */
1432 continue;
1433
1434 if (entry->size < 50)
1435 continue;
1436
1437 if (entry->no_try_delta)
1438 continue;
1439
1440 free_delta_index(n->index);
1441 n->index = NULL;
1442 free(n->data);
1443 n->data = NULL;
1444 n->entry = entry;
1445
1446 /*
1447 * If the current object is at pack edge, take the depth the
1448 * objects that depend on the current object into account
1449 * otherwise they would become too deep.
1450 */
1451 max_depth = depth;
1452 if (entry->delta_child) {
1453 max_depth -= check_delta_limit(entry, 0);
1454 if (max_depth <= 0)
1455 goto next;
1456 }
1457
1458 j = window;
1459 while (--j > 0) {
1460 uint32_t other_idx = idx + j;
1461 struct unpacked *m;
1462 if (other_idx >= window)
1463 other_idx -= window;
1464 m = array + other_idx;
1465 if (!m->entry)
1466 break;
1467 if (try_delta(n, m, max_depth) < 0)
1468 break;
1469 }
1470
1471 /* if we made n a delta, and if n is already at max
1472 * depth, leaving it in the window is pointless. we
1473 * should evict it first.
1474 */
1475 if (entry->delta && depth <= entry->depth)
1476 continue;
1477
1478 next:
1479 idx++;
1480 if (idx >= window)
1481 idx = 0;
1482 } while (i > 0);
1483
1484 if (progress)
1485 stop_progress(&progress_state);
1486
1487 for (i = 0; i < window; ++i) {
1488 free_delta_index(array[i].index);
1489 free(array[i].data);
1490 }
1491 free(array);
1492 }
1493
1494 static void prepare_pack(int window, int depth)
1495 {
1496 struct object_entry **delta_list;
1497 uint32_t i;
1498
1499 get_object_details();
1500
1501 if (!window || !depth)
1502 return;
1503
1504 delta_list = xmalloc(nr_objects * sizeof(*delta_list));
1505 for (i = 0; i < nr_objects; i++)
1506 delta_list[i] = objects + i;
1507 qsort(delta_list, nr_objects, sizeof(*delta_list), type_size_sort);
1508 find_deltas(delta_list, window+1, depth);
1509 free(delta_list);
1510 }
1511
1512 static int git_pack_config(const char *k, const char *v)
1513 {
1514 if(!strcmp(k, "pack.window")) {
1515 window = git_config_int(k, v);
1516 return 0;
1517 }
1518 if(!strcmp(k, "pack.depth")) {
1519 depth = git_config_int(k, v);
1520 return 0;
1521 }
1522 if (!strcmp(k, "pack.compression")) {
1523 int level = git_config_int(k, v);
1524 if (level == -1)
1525 level = Z_DEFAULT_COMPRESSION;
1526 else if (level < 0 || level > Z_BEST_COMPRESSION)
1527 die("bad pack compression level %d", level);
1528 pack_compression_level = level;
1529 pack_compression_seen = 1;
1530 return 0;
1531 }
1532 if (!strcmp(k, "pack.deltacachesize")) {
1533 max_delta_cache_size = git_config_int(k, v);
1534 return 0;
1535 }
1536 if (!strcmp(k, "pack.deltacachelimit")) {
1537 cache_max_small_delta_size = git_config_int(k, v);
1538 return 0;
1539 }
1540 return git_default_config(k, v);
1541 }
1542
1543 static void read_object_list_from_stdin(void)
1544 {
1545 char line[40 + 1 + PATH_MAX + 2];
1546 unsigned char sha1[20];
1547
1548 for (;;) {
1549 if (!fgets(line, sizeof(line), stdin)) {
1550 if (feof(stdin))
1551 break;
1552 if (!ferror(stdin))
1553 die("fgets returned NULL, not EOF, not error!");
1554 if (errno != EINTR)
1555 die("fgets: %s", strerror(errno));
1556 clearerr(stdin);
1557 continue;
1558 }
1559 if (line[0] == '-') {
1560 if (get_sha1_hex(line+1, sha1))
1561 die("expected edge sha1, got garbage:\n %s",
1562 line);
1563 add_preferred_base(sha1);
1564 continue;
1565 }
1566 if (get_sha1_hex(line, sha1))
1567 die("expected sha1, got garbage:\n %s", line);
1568
1569 add_preferred_base_object(line+41);
1570 add_object_entry(sha1, 0, line+41, 0);
1571 }
1572 }
1573
1574 static void show_commit(struct commit *commit)
1575 {
1576 add_object_entry(commit->object.sha1, OBJ_COMMIT, NULL, 0);
1577 }
1578
1579 static void show_object(struct object_array_entry *p)
1580 {
1581 add_preferred_base_object(p->name);
1582 add_object_entry(p->item->sha1, p->item->type, p->name, 0);
1583 }
1584
1585 static void show_edge(struct commit *commit)
1586 {
1587 add_preferred_base(commit->object.sha1);
1588 }
1589
1590 static void get_object_list(int ac, const char **av)
1591 {
1592 struct rev_info revs;
1593 char line[1000];
1594 int flags = 0;
1595
1596 init_revisions(&revs, NULL);
1597 save_commit_buffer = 0;
1598 track_object_refs = 0;
1599 setup_revisions(ac, av, &revs, NULL);
1600
1601 while (fgets(line, sizeof(line), stdin) != NULL) {
1602 int len = strlen(line);
1603 if (line[len - 1] == '\n')
1604 line[--len] = 0;
1605 if (!len)
1606 break;
1607 if (*line == '-') {
1608 if (!strcmp(line, "--not")) {
1609 flags ^= UNINTERESTING;
1610 continue;
1611 }
1612 die("not a rev '%s'", line);
1613 }
1614 if (handle_revision_arg(line, &revs, flags, 1))
1615 die("bad revision '%s'", line);
1616 }
1617
1618 prepare_revision_walk(&revs);
1619 mark_edges_uninteresting(revs.commits, &revs, show_edge);
1620 traverse_commit_list(&revs, show_commit, show_object);
1621 }
1622
1623 static int adjust_perm(const char *path, mode_t mode)
1624 {
1625 if (chmod(path, mode))
1626 return -1;
1627 return adjust_shared_perm(path);
1628 }
1629
1630 int cmd_pack_objects(int argc, const char **argv, const char *prefix)
1631 {
1632 int use_internal_rev_list = 0;
1633 int thin = 0;
1634 uint32_t i;
1635 const char **rp_av;
1636 int rp_ac_alloc = 64;
1637 int rp_ac;
1638
1639 rp_av = xcalloc(rp_ac_alloc, sizeof(*rp_av));
1640
1641 rp_av[0] = "pack-objects";
1642 rp_av[1] = "--objects"; /* --thin will make it --objects-edge */
1643 rp_ac = 2;
1644
1645 git_config(git_pack_config);
1646 if (!pack_compression_seen && core_compression_seen)
1647 pack_compression_level = core_compression_level;
1648
1649 progress = isatty(2);
1650 for (i = 1; i < argc; i++) {
1651 const char *arg = argv[i];
1652
1653 if (*arg != '-')
1654 break;
1655
1656 if (!strcmp("--non-empty", arg)) {
1657 non_empty = 1;
1658 continue;
1659 }
1660 if (!strcmp("--local", arg)) {
1661 local = 1;
1662 continue;
1663 }
1664 if (!strcmp("--incremental", arg)) {
1665 incremental = 1;
1666 continue;
1667 }
1668 if (!prefixcmp(arg, "--compression=")) {
1669 char *end;
1670 int level = strtoul(arg+14, &end, 0);
1671 if (!arg[14] || *end)
1672 usage(pack_usage);
1673 if (level == -1)
1674 level = Z_DEFAULT_COMPRESSION;
1675 else if (level < 0 || level > Z_BEST_COMPRESSION)
1676 die("bad pack compression level %d", level);
1677 pack_compression_level = level;
1678 continue;
1679 }
1680 if (!prefixcmp(arg, "--max-pack-size=")) {
1681 char *end;
1682 pack_size_limit = strtoul(arg+16, &end, 0) * 1024 * 1024;
1683 if (!arg[16] || *end)
1684 usage(pack_usage);
1685 continue;
1686 }
1687 if (!prefixcmp(arg, "--window=")) {
1688 char *end;
1689 window = strtoul(arg+9, &end, 0);
1690 if (!arg[9] || *end)
1691 usage(pack_usage);
1692 continue;
1693 }
1694 if (!prefixcmp(arg, "--depth=")) {
1695 char *end;
1696 depth = strtoul(arg+8, &end, 0);
1697 if (!arg[8] || *end)
1698 usage(pack_usage);
1699 continue;
1700 }
1701 if (!strcmp("--progress", arg)) {
1702 progress = 1;
1703 continue;
1704 }
1705 if (!strcmp("--all-progress", arg)) {
1706 progress = 2;
1707 continue;
1708 }
1709 if (!strcmp("-q", arg)) {
1710 progress = 0;
1711 continue;
1712 }
1713 if (!strcmp("--no-reuse-delta", arg)) {
1714 no_reuse_delta = 1;
1715 continue;
1716 }
1717 if (!strcmp("--no-reuse-object", arg)) {
1718 no_reuse_object = no_reuse_delta = 1;
1719 continue;
1720 }
1721 if (!strcmp("--delta-base-offset", arg)) {
1722 allow_ofs_delta = 1;
1723 continue;
1724 }
1725 if (!strcmp("--stdout", arg)) {
1726 pack_to_stdout = 1;
1727 continue;
1728 }
1729 if (!strcmp("--revs", arg)) {
1730 use_internal_rev_list = 1;
1731 continue;
1732 }
1733 if (!strcmp("--unpacked", arg) ||
1734 !prefixcmp(arg, "--unpacked=") ||
1735 !strcmp("--reflog", arg) ||
1736 !strcmp("--all", arg)) {
1737 use_internal_rev_list = 1;
1738 if (rp_ac >= rp_ac_alloc - 1) {
1739 rp_ac_alloc = alloc_nr(rp_ac_alloc);
1740 rp_av = xrealloc(rp_av,
1741 rp_ac_alloc * sizeof(*rp_av));
1742 }
1743 rp_av[rp_ac++] = arg;
1744 continue;
1745 }
1746 if (!strcmp("--thin", arg)) {
1747 use_internal_rev_list = 1;
1748 thin = 1;
1749 rp_av[1] = "--objects-edge";
1750 continue;
1751 }
1752 if (!prefixcmp(arg, "--index-version=")) {
1753 char *c;
1754 pack_idx_default_version = strtoul(arg + 16, &c, 10);
1755 if (pack_idx_default_version > 2)
1756 die("bad %s", arg);
1757 if (*c == ',')
1758 pack_idx_off32_limit = strtoul(c+1, &c, 0);
1759 if (*c || pack_idx_off32_limit & 0x80000000)
1760 die("bad %s", arg);
1761 continue;
1762 }
1763 usage(pack_usage);
1764 }
1765
1766 /* Traditionally "pack-objects [options] base extra" failed;
1767 * we would however want to take refs parameter that would
1768 * have been given to upstream rev-list ourselves, which means
1769 * we somehow want to say what the base name is. So the
1770 * syntax would be:
1771 *
1772 * pack-objects [options] base <refs...>
1773 *
1774 * in other words, we would treat the first non-option as the
1775 * base_name and send everything else to the internal revision
1776 * walker.
1777 */
1778
1779 if (!pack_to_stdout)
1780 base_name = argv[i++];
1781
1782 if (pack_to_stdout != !base_name)
1783 usage(pack_usage);
1784
1785 if (pack_to_stdout && pack_size_limit)
1786 die("--max-pack-size cannot be used to build a pack for transfer.");
1787
1788 if (!pack_to_stdout && thin)
1789 die("--thin cannot be used to build an indexable pack.");
1790
1791 prepare_packed_git();
1792
1793 if (progress)
1794 start_progress(&progress_state, "Generating pack...",
1795 "Counting objects: ", 0);
1796 if (!use_internal_rev_list)
1797 read_object_list_from_stdin();
1798 else {
1799 rp_av[rp_ac] = NULL;
1800 get_object_list(rp_ac, rp_av);
1801 }
1802 if (progress) {
1803 stop_progress(&progress_state);
1804 fprintf(stderr, "Done counting %u objects.\n", nr_objects);
1805 }
1806
1807 if (non_empty && !nr_result)
1808 return 0;
1809 if (progress && (nr_objects != nr_result))
1810 fprintf(stderr, "Result has %u objects.\n", nr_result);
1811 if (nr_result)
1812 prepare_pack(window, depth);
1813 write_pack_file();
1814 if (progress)
1815 fprintf(stderr, "Total %u (delta %u), reused %u (delta %u)\n",
1816 written, written_delta, reused, reused_delta);
1817 return 0;
1818 }