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9d565925e7133d5baad8c31e1303e99cf6ecf0a7
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"
18 static const char pack_usage[] = "\
19 git-pack-objects [{ -q | --progress | --all-progress }] \n\
20 [--max-pack-size=N] [--local] [--incremental] \n\
21 [--window=N] [--window-memory=N] [--depth=N] \n\
22 [--no-reuse-delta] [--no-reuse-object] [--delta-base-offset] \n\
23 [--non-empty] [--revs [--unpacked | --all]*] [--reflog] \n\
24 [--stdout | base-name] [<ref-list | <object-list]";
26 struct object_entry {
27 struct pack_idx_entry idx;
28 unsigned long size; /* uncompressed size */
29 struct packed_git *in_pack; /* already in pack */
30 off_t in_pack_offset;
31 struct object_entry *delta; /* delta base object */
32 struct object_entry *delta_child; /* deltified objects who bases me */
33 struct object_entry *delta_sibling; /* other deltified objects who
34 * uses the same base as me
35 */
36 void *delta_data; /* cached delta (uncompressed) */
37 unsigned long delta_size; /* delta data size (uncompressed) */
38 unsigned int hash; /* name hint hash */
39 enum object_type type;
40 enum object_type in_pack_type; /* could be delta */
41 unsigned char in_pack_header_size;
42 unsigned char preferred_base; /* we do not pack this, but is available
43 * to be used as the base object to delta
44 * objects against.
45 */
46 unsigned char no_try_delta;
47 };
49 /*
50 * Objects we are going to pack are collected in objects array (dynamically
51 * expanded). nr_objects & nr_alloc controls this array. They are stored
52 * in the order we see -- typically rev-list --objects order that gives us
53 * nice "minimum seek" order.
54 */
55 static struct object_entry *objects;
56 static struct object_entry **written_list;
57 static uint32_t nr_objects, nr_alloc, nr_result, nr_written;
59 static int non_empty;
60 static int no_reuse_delta, no_reuse_object;
61 static int local;
62 static int incremental;
63 static int allow_ofs_delta;
64 static const char *pack_tmp_name, *idx_tmp_name;
65 static char tmpname[PATH_MAX];
66 static const char *base_name;
67 static int progress = 1;
68 static int window = 10;
69 static uint32_t pack_size_limit;
70 static int depth = 50;
71 static int pack_to_stdout;
72 static int num_preferred_base;
73 static struct progress progress_state;
74 static int pack_compression_level = Z_DEFAULT_COMPRESSION;
75 static int pack_compression_seen;
77 static unsigned long delta_cache_size = 0;
78 static unsigned long max_delta_cache_size = 0;
79 static unsigned long cache_max_small_delta_size = 1000;
81 static unsigned long window_memory_limit = 0;
83 /*
84 * The object names in objects array are hashed with this hashtable,
85 * to help looking up the entry by object name.
86 * This hashtable is built after all the objects are seen.
87 */
88 static int *object_ix;
89 static int object_ix_hashsz;
91 /*
92 * Pack index for existing packs give us easy access to the offsets into
93 * corresponding pack file where each object's data starts, but the entries
94 * do not store the size of the compressed representation (uncompressed
95 * size is easily available by examining the pack entry header). It is
96 * also rather expensive to find the sha1 for an object given its offset.
97 *
98 * We build a hashtable of existing packs (pack_revindex), and keep reverse
99 * index here -- pack index file is sorted by object name mapping to offset;
100 * this pack_revindex[].revindex array is a list of offset/index_nr pairs
101 * ordered by offset, so if you know the offset of an object, next offset
102 * is where its packed representation ends and the index_nr can be used to
103 * get the object sha1 from the main index.
104 */
105 struct revindex_entry {
106 off_t offset;
107 unsigned int nr;
108 };
109 struct pack_revindex {
110 struct packed_git *p;
111 struct revindex_entry *revindex;
112 };
113 static struct pack_revindex *pack_revindex;
114 static int pack_revindex_hashsz;
116 /*
117 * stats
118 */
119 static uint32_t written, written_delta;
120 static uint32_t reused, reused_delta;
122 static int pack_revindex_ix(struct packed_git *p)
123 {
124 unsigned long ui = (unsigned long)p;
125 int i;
127 ui = ui ^ (ui >> 16); /* defeat structure alignment */
128 i = (int)(ui % pack_revindex_hashsz);
129 while (pack_revindex[i].p) {
130 if (pack_revindex[i].p == p)
131 return i;
132 if (++i == pack_revindex_hashsz)
133 i = 0;
134 }
135 return -1 - i;
136 }
138 static void prepare_pack_ix(void)
139 {
140 int num;
141 struct packed_git *p;
142 for (num = 0, p = packed_git; p; p = p->next)
143 num++;
144 if (!num)
145 return;
146 pack_revindex_hashsz = num * 11;
147 pack_revindex = xcalloc(sizeof(*pack_revindex), pack_revindex_hashsz);
148 for (p = packed_git; p; p = p->next) {
149 num = pack_revindex_ix(p);
150 num = - 1 - num;
151 pack_revindex[num].p = p;
152 }
153 /* revindex elements are lazily initialized */
154 }
156 static int cmp_offset(const void *a_, const void *b_)
157 {
158 const struct revindex_entry *a = a_;
159 const struct revindex_entry *b = b_;
160 return (a->offset < b->offset) ? -1 : (a->offset > b->offset) ? 1 : 0;
161 }
163 /*
164 * Ordered list of offsets of objects in the pack.
165 */
166 static void prepare_pack_revindex(struct pack_revindex *rix)
167 {
168 struct packed_git *p = rix->p;
169 int num_ent = p->num_objects;
170 int i;
171 const char *index = p->index_data;
173 rix->revindex = xmalloc(sizeof(*rix->revindex) * (num_ent + 1));
174 index += 4 * 256;
176 if (p->index_version > 1) {
177 const uint32_t *off_32 =
178 (uint32_t *)(index + 8 + p->num_objects * (20 + 4));
179 const uint32_t *off_64 = off_32 + p->num_objects;
180 for (i = 0; i < num_ent; i++) {
181 uint32_t off = ntohl(*off_32++);
182 if (!(off & 0x80000000)) {
183 rix->revindex[i].offset = off;
184 } else {
185 rix->revindex[i].offset =
186 ((uint64_t)ntohl(*off_64++)) << 32;
187 rix->revindex[i].offset |=
188 ntohl(*off_64++);
189 }
190 rix->revindex[i].nr = i;
191 }
192 } else {
193 for (i = 0; i < num_ent; i++) {
194 uint32_t hl = *((uint32_t *)(index + 24 * i));
195 rix->revindex[i].offset = ntohl(hl);
196 rix->revindex[i].nr = i;
197 }
198 }
200 /* This knows the pack format -- the 20-byte trailer
201 * follows immediately after the last object data.
202 */
203 rix->revindex[num_ent].offset = p->pack_size - 20;
204 rix->revindex[num_ent].nr = -1;
205 qsort(rix->revindex, num_ent, sizeof(*rix->revindex), cmp_offset);
206 }
208 static struct revindex_entry * find_packed_object(struct packed_git *p,
209 off_t ofs)
210 {
211 int num;
212 int lo, hi;
213 struct pack_revindex *rix;
214 struct revindex_entry *revindex;
215 num = pack_revindex_ix(p);
216 if (num < 0)
217 die("internal error: pack revindex uninitialized");
218 rix = &pack_revindex[num];
219 if (!rix->revindex)
220 prepare_pack_revindex(rix);
221 revindex = rix->revindex;
222 lo = 0;
223 hi = p->num_objects + 1;
224 do {
225 int mi = (lo + hi) / 2;
226 if (revindex[mi].offset == ofs) {
227 return revindex + mi;
228 }
229 else if (ofs < revindex[mi].offset)
230 hi = mi;
231 else
232 lo = mi + 1;
233 } while (lo < hi);
234 die("internal error: pack revindex corrupt");
235 }
237 static const unsigned char *find_packed_object_name(struct packed_git *p,
238 off_t ofs)
239 {
240 struct revindex_entry *entry = find_packed_object(p, ofs);
241 return nth_packed_object_sha1(p, entry->nr);
242 }
244 static void *delta_against(void *buf, unsigned long size, struct object_entry *entry)
245 {
246 unsigned long othersize, delta_size;
247 enum object_type type;
248 void *otherbuf = read_sha1_file(entry->delta->idx.sha1, &type, &othersize);
249 void *delta_buf;
251 if (!otherbuf)
252 die("unable to read %s", sha1_to_hex(entry->delta->idx.sha1));
253 delta_buf = diff_delta(otherbuf, othersize,
254 buf, size, &delta_size, 0);
255 if (!delta_buf || delta_size != entry->delta_size)
256 die("delta size changed");
257 free(buf);
258 free(otherbuf);
259 return delta_buf;
260 }
262 /*
263 * The per-object header is a pretty dense thing, which is
264 * - first byte: low four bits are "size", then three bits of "type",
265 * and the high bit is "size continues".
266 * - each byte afterwards: low seven bits are size continuation,
267 * with the high bit being "size continues"
268 */
269 static int encode_header(enum object_type type, unsigned long size, unsigned char *hdr)
270 {
271 int n = 1;
272 unsigned char c;
274 if (type < OBJ_COMMIT || type > OBJ_REF_DELTA)
275 die("bad type %d", type);
277 c = (type << 4) | (size & 15);
278 size >>= 4;
279 while (size) {
280 *hdr++ = c | 0x80;
281 c = size & 0x7f;
282 size >>= 7;
283 n++;
284 }
285 *hdr = c;
286 return n;
287 }
289 /*
290 * we are going to reuse the existing object data as is. make
291 * sure it is not corrupt.
292 */
293 static int check_pack_inflate(struct packed_git *p,
294 struct pack_window **w_curs,
295 off_t offset,
296 off_t len,
297 unsigned long expect)
298 {
299 z_stream stream;
300 unsigned char fakebuf[4096], *in;
301 int st;
303 memset(&stream, 0, sizeof(stream));
304 inflateInit(&stream);
305 do {
306 in = use_pack(p, w_curs, offset, &stream.avail_in);
307 stream.next_in = in;
308 stream.next_out = fakebuf;
309 stream.avail_out = sizeof(fakebuf);
310 st = inflate(&stream, Z_FINISH);
311 offset += stream.next_in - in;
312 } while (st == Z_OK || st == Z_BUF_ERROR);
313 inflateEnd(&stream);
314 return (st == Z_STREAM_END &&
315 stream.total_out == expect &&
316 stream.total_in == len) ? 0 : -1;
317 }
319 static int check_pack_crc(struct packed_git *p, struct pack_window **w_curs,
320 off_t offset, off_t len, unsigned int nr)
321 {
322 const uint32_t *index_crc;
323 uint32_t data_crc = crc32(0, Z_NULL, 0);
325 do {
326 unsigned int avail;
327 void *data = use_pack(p, w_curs, offset, &avail);
328 if (avail > len)
329 avail = len;
330 data_crc = crc32(data_crc, data, avail);
331 offset += avail;
332 len -= avail;
333 } while (len);
335 index_crc = p->index_data;
336 index_crc += 2 + 256 + p->num_objects * (20/4) + nr;
338 return data_crc != ntohl(*index_crc);
339 }
341 static void copy_pack_data(struct sha1file *f,
342 struct packed_git *p,
343 struct pack_window **w_curs,
344 off_t offset,
345 off_t len)
346 {
347 unsigned char *in;
348 unsigned int avail;
350 while (len) {
351 in = use_pack(p, w_curs, offset, &avail);
352 if (avail > len)
353 avail = (unsigned int)len;
354 sha1write(f, in, avail);
355 offset += avail;
356 len -= avail;
357 }
358 }
360 static unsigned long write_object(struct sha1file *f,
361 struct object_entry *entry,
362 off_t write_offset)
363 {
364 unsigned long size;
365 enum object_type type;
366 void *buf;
367 unsigned char header[10];
368 unsigned char dheader[10];
369 unsigned hdrlen;
370 off_t datalen;
371 enum object_type obj_type;
372 int to_reuse = 0;
373 /* write limit if limited packsize and not first object */
374 unsigned long limit = pack_size_limit && nr_written ?
375 pack_size_limit - write_offset : 0;
376 /* no if no delta */
377 int usable_delta = !entry->delta ? 0 :
378 /* yes if unlimited packfile */
379 !pack_size_limit ? 1 :
380 /* no if base written to previous pack */
381 entry->delta->idx.offset == (off_t)-1 ? 0 :
382 /* otherwise double-check written to this
383 * pack, like we do below
384 */
385 entry->delta->idx.offset ? 1 : 0;
387 if (!pack_to_stdout)
388 crc32_begin(f);
390 obj_type = entry->type;
391 if (no_reuse_object)
392 to_reuse = 0; /* explicit */
393 else if (!entry->in_pack)
394 to_reuse = 0; /* can't reuse what we don't have */
395 else if (obj_type == OBJ_REF_DELTA || obj_type == OBJ_OFS_DELTA)
396 /* check_object() decided it for us ... */
397 to_reuse = usable_delta;
398 /* ... but pack split may override that */
399 else if (obj_type != entry->in_pack_type)
400 to_reuse = 0; /* pack has delta which is unusable */
401 else if (entry->delta)
402 to_reuse = 0; /* we want to pack afresh */
403 else
404 to_reuse = 1; /* we have it in-pack undeltified,
405 * and we do not need to deltify it.
406 */
408 if (!to_reuse) {
409 z_stream stream;
410 unsigned long maxsize;
411 void *out;
412 if (!usable_delta) {
413 buf = read_sha1_file(entry->idx.sha1, &obj_type, &size);
414 if (!buf)
415 die("unable to read %s", sha1_to_hex(entry->idx.sha1));
416 } else if (entry->delta_data) {
417 size = entry->delta_size;
418 buf = entry->delta_data;
419 entry->delta_data = NULL;
420 obj_type = (allow_ofs_delta && entry->delta->idx.offset) ?
421 OBJ_OFS_DELTA : OBJ_REF_DELTA;
422 } else {
423 buf = read_sha1_file(entry->idx.sha1, &type, &size);
424 if (!buf)
425 die("unable to read %s", sha1_to_hex(entry->idx.sha1));
426 buf = delta_against(buf, size, entry);
427 size = entry->delta_size;
428 obj_type = (allow_ofs_delta && entry->delta->idx.offset) ?
429 OBJ_OFS_DELTA : OBJ_REF_DELTA;
430 }
431 /* compress the data to store and put compressed length in datalen */
432 memset(&stream, 0, sizeof(stream));
433 deflateInit(&stream, pack_compression_level);
434 maxsize = deflateBound(&stream, size);
435 out = xmalloc(maxsize);
436 /* Compress it */
437 stream.next_in = buf;
438 stream.avail_in = size;
439 stream.next_out = out;
440 stream.avail_out = maxsize;
441 while (deflate(&stream, Z_FINISH) == Z_OK)
442 /* nothing */;
443 deflateEnd(&stream);
444 datalen = stream.total_out;
445 deflateEnd(&stream);
446 /*
447 * The object header is a byte of 'type' followed by zero or
448 * more bytes of length.
449 */
450 hdrlen = encode_header(obj_type, size, header);
452 if (obj_type == OBJ_OFS_DELTA) {
453 /*
454 * Deltas with relative base contain an additional
455 * encoding of the relative offset for the delta
456 * base from this object's position in the pack.
457 */
458 off_t ofs = entry->idx.offset - entry->delta->idx.offset;
459 unsigned pos = sizeof(dheader) - 1;
460 dheader[pos] = ofs & 127;
461 while (ofs >>= 7)
462 dheader[--pos] = 128 | (--ofs & 127);
463 if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit) {
464 free(out);
465 free(buf);
466 return 0;
467 }
468 sha1write(f, header, hdrlen);
469 sha1write(f, dheader + pos, sizeof(dheader) - pos);
470 hdrlen += sizeof(dheader) - pos;
471 } else if (obj_type == OBJ_REF_DELTA) {
472 /*
473 * Deltas with a base reference contain
474 * an additional 20 bytes for the base sha1.
475 */
476 if (limit && hdrlen + 20 + datalen + 20 >= limit) {
477 free(out);
478 free(buf);
479 return 0;
480 }
481 sha1write(f, header, hdrlen);
482 sha1write(f, entry->delta->idx.sha1, 20);
483 hdrlen += 20;
484 } else {
485 if (limit && hdrlen + datalen + 20 >= limit) {
486 free(out);
487 free(buf);
488 return 0;
489 }
490 sha1write(f, header, hdrlen);
491 }
492 sha1write(f, out, datalen);
493 free(out);
494 free(buf);
495 }
496 else {
497 struct packed_git *p = entry->in_pack;
498 struct pack_window *w_curs = NULL;
499 struct revindex_entry *revidx;
500 off_t offset;
502 if (entry->delta) {
503 obj_type = (allow_ofs_delta && entry->delta->idx.offset) ?
504 OBJ_OFS_DELTA : OBJ_REF_DELTA;
505 reused_delta++;
506 }
507 hdrlen = encode_header(obj_type, entry->size, header);
508 offset = entry->in_pack_offset;
509 revidx = find_packed_object(p, offset);
510 datalen = revidx[1].offset - offset;
511 if (!pack_to_stdout && p->index_version > 1 &&
512 check_pack_crc(p, &w_curs, offset, datalen, revidx->nr))
513 die("bad packed object CRC for %s", sha1_to_hex(entry->idx.sha1));
514 offset += entry->in_pack_header_size;
515 datalen -= entry->in_pack_header_size;
516 if (obj_type == OBJ_OFS_DELTA) {
517 off_t ofs = entry->idx.offset - entry->delta->idx.offset;
518 unsigned pos = sizeof(dheader) - 1;
519 dheader[pos] = ofs & 127;
520 while (ofs >>= 7)
521 dheader[--pos] = 128 | (--ofs & 127);
522 if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit)
523 return 0;
524 sha1write(f, header, hdrlen);
525 sha1write(f, dheader + pos, sizeof(dheader) - pos);
526 hdrlen += sizeof(dheader) - pos;
527 } else if (obj_type == OBJ_REF_DELTA) {
528 if (limit && hdrlen + 20 + datalen + 20 >= limit)
529 return 0;
530 sha1write(f, header, hdrlen);
531 sha1write(f, entry->delta->idx.sha1, 20);
532 hdrlen += 20;
533 } else {
534 if (limit && hdrlen + datalen + 20 >= limit)
535 return 0;
536 sha1write(f, header, hdrlen);
537 }
539 if (!pack_to_stdout && p->index_version == 1 &&
540 check_pack_inflate(p, &w_curs, offset, datalen, entry->size))
541 die("corrupt packed object for %s", sha1_to_hex(entry->idx.sha1));
542 copy_pack_data(f, p, &w_curs, offset, datalen);
543 unuse_pack(&w_curs);
544 reused++;
545 }
546 if (usable_delta)
547 written_delta++;
548 written++;
549 if (!pack_to_stdout)
550 entry->idx.crc32 = crc32_end(f);
551 return hdrlen + datalen;
552 }
554 static off_t write_one(struct sha1file *f,
555 struct object_entry *e,
556 off_t offset)
557 {
558 unsigned long size;
560 /* offset is non zero if object is written already. */
561 if (e->idx.offset || e->preferred_base)
562 return offset;
564 /* if we are deltified, write out base object first. */
565 if (e->delta) {
566 offset = write_one(f, e->delta, offset);
567 if (!offset)
568 return 0;
569 }
571 e->idx.offset = offset;
572 size = write_object(f, e, offset);
573 if (!size) {
574 e->idx.offset = 0;
575 return 0;
576 }
577 written_list[nr_written++] = e;
579 /* make sure off_t is sufficiently large not to wrap */
580 if (offset > offset + size)
581 die("pack too large for current definition of off_t");
582 return offset + size;
583 }
585 static int open_object_dir_tmp(const char *path)
586 {
587 snprintf(tmpname, sizeof(tmpname), "%s/%s", get_object_directory(), path);
588 return xmkstemp(tmpname);
589 }
591 /* forward declaration for write_pack_file */
592 static int adjust_perm(const char *path, mode_t mode);
594 static void write_pack_file(void)
595 {
596 uint32_t i = 0, j;
597 struct sha1file *f;
598 off_t offset, offset_one, last_obj_offset = 0;
599 struct pack_header hdr;
600 int do_progress = progress >> pack_to_stdout;
601 uint32_t nr_remaining = nr_result;
603 if (do_progress)
604 start_progress(&progress_state, "Writing %u objects...", "", nr_result);
605 written_list = xmalloc(nr_objects * sizeof(struct object_entry *));
607 do {
608 unsigned char sha1[20];
610 if (pack_to_stdout) {
611 f = sha1fd(1, "<stdout>");
612 } else {
613 int fd = open_object_dir_tmp("tmp_pack_XXXXXX");
614 pack_tmp_name = xstrdup(tmpname);
615 f = sha1fd(fd, pack_tmp_name);
616 }
618 hdr.hdr_signature = htonl(PACK_SIGNATURE);
619 hdr.hdr_version = htonl(PACK_VERSION);
620 hdr.hdr_entries = htonl(nr_remaining);
621 sha1write(f, &hdr, sizeof(hdr));
622 offset = sizeof(hdr);
623 nr_written = 0;
624 for (; i < nr_objects; i++) {
625 last_obj_offset = offset;
626 offset_one = write_one(f, objects + i, offset);
627 if (!offset_one)
628 break;
629 offset = offset_one;
630 if (do_progress)
631 display_progress(&progress_state, written);
632 }
634 /*
635 * Did we write the wrong # entries in the header?
636 * If so, rewrite it like in fast-import
637 */
638 if (pack_to_stdout || nr_written == nr_remaining) {
639 sha1close(f, sha1, 1);
640 } else {
641 sha1close(f, sha1, 0);
642 fixup_pack_header_footer(f->fd, sha1, pack_tmp_name, nr_written);
643 close(f->fd);
644 }
646 if (!pack_to_stdout) {
647 mode_t mode = umask(0);
649 umask(mode);
650 mode = 0444 & ~mode;
652 idx_tmp_name = write_idx_file(NULL,
653 (struct pack_idx_entry **) written_list, nr_written, sha1);
654 snprintf(tmpname, sizeof(tmpname), "%s-%s.pack",
655 base_name, sha1_to_hex(sha1));
656 if (adjust_perm(pack_tmp_name, mode))
657 die("unable to make temporary pack file readable: %s",
658 strerror(errno));
659 if (rename(pack_tmp_name, tmpname))
660 die("unable to rename temporary pack file: %s",
661 strerror(errno));
662 snprintf(tmpname, sizeof(tmpname), "%s-%s.idx",
663 base_name, sha1_to_hex(sha1));
664 if (adjust_perm(idx_tmp_name, mode))
665 die("unable to make temporary index file readable: %s",
666 strerror(errno));
667 if (rename(idx_tmp_name, tmpname))
668 die("unable to rename temporary index file: %s",
669 strerror(errno));
670 puts(sha1_to_hex(sha1));
671 }
673 /* mark written objects as written to previous pack */
674 for (j = 0; j < nr_written; j++) {
675 written_list[j]->idx.offset = (off_t)-1;
676 }
677 nr_remaining -= nr_written;
678 } while (nr_remaining && i < nr_objects);
680 free(written_list);
681 if (do_progress)
682 stop_progress(&progress_state);
683 if (written != nr_result)
684 die("wrote %u objects while expecting %u", written, nr_result);
685 /*
686 * We have scanned through [0 ... i). Since we have written
687 * the correct number of objects, the remaining [i ... nr_objects)
688 * items must be either already written (due to out-of-order delta base)
689 * or a preferred base. Count those which are neither and complain if any.
690 */
691 for (j = 0; i < nr_objects; i++) {
692 struct object_entry *e = objects + i;
693 j += !e->idx.offset && !e->preferred_base;
694 }
695 if (j)
696 die("wrote %u objects as expected but %u unwritten", written, j);
697 }
699 static int locate_object_entry_hash(const unsigned char *sha1)
700 {
701 int i;
702 unsigned int ui;
703 memcpy(&ui, sha1, sizeof(unsigned int));
704 i = ui % object_ix_hashsz;
705 while (0 < object_ix[i]) {
706 if (!hashcmp(sha1, objects[object_ix[i] - 1].idx.sha1))
707 return i;
708 if (++i == object_ix_hashsz)
709 i = 0;
710 }
711 return -1 - i;
712 }
714 static struct object_entry *locate_object_entry(const unsigned char *sha1)
715 {
716 int i;
718 if (!object_ix_hashsz)
719 return NULL;
721 i = locate_object_entry_hash(sha1);
722 if (0 <= i)
723 return &objects[object_ix[i]-1];
724 return NULL;
725 }
727 static void rehash_objects(void)
728 {
729 uint32_t i;
730 struct object_entry *oe;
732 object_ix_hashsz = nr_objects * 3;
733 if (object_ix_hashsz < 1024)
734 object_ix_hashsz = 1024;
735 object_ix = xrealloc(object_ix, sizeof(int) * object_ix_hashsz);
736 memset(object_ix, 0, sizeof(int) * object_ix_hashsz);
737 for (i = 0, oe = objects; i < nr_objects; i++, oe++) {
738 int ix = locate_object_entry_hash(oe->idx.sha1);
739 if (0 <= ix)
740 continue;
741 ix = -1 - ix;
742 object_ix[ix] = i + 1;
743 }
744 }
746 static unsigned name_hash(const char *name)
747 {
748 unsigned char c;
749 unsigned hash = 0;
751 if (!name)
752 return 0;
754 /*
755 * This effectively just creates a sortable number from the
756 * last sixteen non-whitespace characters. Last characters
757 * count "most", so things that end in ".c" sort together.
758 */
759 while ((c = *name++) != 0) {
760 if (isspace(c))
761 continue;
762 hash = (hash >> 2) + (c << 24);
763 }
764 return hash;
765 }
767 static void setup_delta_attr_check(struct git_attr_check *check)
768 {
769 static struct git_attr *attr_delta;
771 if (!attr_delta)
772 attr_delta = git_attr("delta", 5);
774 check[0].attr = attr_delta;
775 }
777 static int no_try_delta(const char *path)
778 {
779 struct git_attr_check check[1];
781 setup_delta_attr_check(check);
782 if (git_checkattr(path, ARRAY_SIZE(check), check))
783 return 0;
784 if (ATTR_FALSE(check->value))
785 return 1;
786 return 0;
787 }
789 static int add_object_entry(const unsigned char *sha1, enum object_type type,
790 const char *name, int exclude)
791 {
792 struct object_entry *entry;
793 struct packed_git *p, *found_pack = NULL;
794 off_t found_offset = 0;
795 int ix;
796 unsigned hash = name_hash(name);
798 ix = nr_objects ? locate_object_entry_hash(sha1) : -1;
799 if (ix >= 0) {
800 if (exclude) {
801 entry = objects + object_ix[ix] - 1;
802 if (!entry->preferred_base)
803 nr_result--;
804 entry->preferred_base = 1;
805 }
806 return 0;
807 }
809 for (p = packed_git; p; p = p->next) {
810 off_t offset = find_pack_entry_one(sha1, p);
811 if (offset) {
812 if (!found_pack) {
813 found_offset = offset;
814 found_pack = p;
815 }
816 if (exclude)
817 break;
818 if (incremental)
819 return 0;
820 if (local && !p->pack_local)
821 return 0;
822 }
823 }
825 if (nr_objects >= nr_alloc) {
826 nr_alloc = (nr_alloc + 1024) * 3 / 2;
827 objects = xrealloc(objects, nr_alloc * sizeof(*entry));
828 }
830 entry = objects + nr_objects++;
831 memset(entry, 0, sizeof(*entry));
832 hashcpy(entry->idx.sha1, sha1);
833 entry->hash = hash;
834 if (type)
835 entry->type = type;
836 if (exclude)
837 entry->preferred_base = 1;
838 else
839 nr_result++;
840 if (found_pack) {
841 entry->in_pack = found_pack;
842 entry->in_pack_offset = found_offset;
843 }
845 if (object_ix_hashsz * 3 <= nr_objects * 4)
846 rehash_objects();
847 else
848 object_ix[-1 - ix] = nr_objects;
850 if (progress)
851 display_progress(&progress_state, nr_objects);
853 if (name && no_try_delta(name))
854 entry->no_try_delta = 1;
856 return 1;
857 }
859 struct pbase_tree_cache {
860 unsigned char sha1[20];
861 int ref;
862 int temporary;
863 void *tree_data;
864 unsigned long tree_size;
865 };
867 static struct pbase_tree_cache *(pbase_tree_cache[256]);
868 static int pbase_tree_cache_ix(const unsigned char *sha1)
869 {
870 return sha1[0] % ARRAY_SIZE(pbase_tree_cache);
871 }
872 static int pbase_tree_cache_ix_incr(int ix)
873 {
874 return (ix+1) % ARRAY_SIZE(pbase_tree_cache);
875 }
877 static struct pbase_tree {
878 struct pbase_tree *next;
879 /* This is a phony "cache" entry; we are not
880 * going to evict it nor find it through _get()
881 * mechanism -- this is for the toplevel node that
882 * would almost always change with any commit.
883 */
884 struct pbase_tree_cache pcache;
885 } *pbase_tree;
887 static struct pbase_tree_cache *pbase_tree_get(const unsigned char *sha1)
888 {
889 struct pbase_tree_cache *ent, *nent;
890 void *data;
891 unsigned long size;
892 enum object_type type;
893 int neigh;
894 int my_ix = pbase_tree_cache_ix(sha1);
895 int available_ix = -1;
897 /* pbase-tree-cache acts as a limited hashtable.
898 * your object will be found at your index or within a few
899 * slots after that slot if it is cached.
900 */
901 for (neigh = 0; neigh < 8; neigh++) {
902 ent = pbase_tree_cache[my_ix];
903 if (ent && !hashcmp(ent->sha1, sha1)) {
904 ent->ref++;
905 return ent;
906 }
907 else if (((available_ix < 0) && (!ent || !ent->ref)) ||
908 ((0 <= available_ix) &&
909 (!ent && pbase_tree_cache[available_ix])))
910 available_ix = my_ix;
911 if (!ent)
912 break;
913 my_ix = pbase_tree_cache_ix_incr(my_ix);
914 }
916 /* Did not find one. Either we got a bogus request or
917 * we need to read and perhaps cache.
918 */
919 data = read_sha1_file(sha1, &type, &size);
920 if (!data)
921 return NULL;
922 if (type != OBJ_TREE) {
923 free(data);
924 return NULL;
925 }
927 /* We need to either cache or return a throwaway copy */
929 if (available_ix < 0)
930 ent = NULL;
931 else {
932 ent = pbase_tree_cache[available_ix];
933 my_ix = available_ix;
934 }
936 if (!ent) {
937 nent = xmalloc(sizeof(*nent));
938 nent->temporary = (available_ix < 0);
939 }
940 else {
941 /* evict and reuse */
942 free(ent->tree_data);
943 nent = ent;
944 }
945 hashcpy(nent->sha1, sha1);
946 nent->tree_data = data;
947 nent->tree_size = size;
948 nent->ref = 1;
949 if (!nent->temporary)
950 pbase_tree_cache[my_ix] = nent;
951 return nent;
952 }
954 static void pbase_tree_put(struct pbase_tree_cache *cache)
955 {
956 if (!cache->temporary) {
957 cache->ref--;
958 return;
959 }
960 free(cache->tree_data);
961 free(cache);
962 }
964 static int name_cmp_len(const char *name)
965 {
966 int i;
967 for (i = 0; name[i] && name[i] != '\n' && name[i] != '/'; i++)
968 ;
969 return i;
970 }
972 static void add_pbase_object(struct tree_desc *tree,
973 const char *name,
974 int cmplen,
975 const char *fullname)
976 {
977 struct name_entry entry;
978 int cmp;
980 while (tree_entry(tree,&entry)) {
981 if (S_ISGITLINK(entry.mode))
982 continue;
983 cmp = tree_entry_len(entry.path, entry.sha1) != cmplen ? 1 :
984 memcmp(name, entry.path, cmplen);
985 if (cmp > 0)
986 continue;
987 if (cmp < 0)
988 return;
989 if (name[cmplen] != '/') {
990 add_object_entry(entry.sha1,
991 S_ISDIR(entry.mode) ? OBJ_TREE : OBJ_BLOB,
992 fullname, 1);
993 return;
994 }
995 if (S_ISDIR(entry.mode)) {
996 struct tree_desc sub;
997 struct pbase_tree_cache *tree;
998 const char *down = name+cmplen+1;
999 int downlen = name_cmp_len(down);
1001 tree = pbase_tree_get(entry.sha1);
1002 if (!tree)
1003 return;
1004 init_tree_desc(&sub, tree->tree_data, tree->tree_size);
1006 add_pbase_object(&sub, down, downlen, fullname);
1007 pbase_tree_put(tree);
1008 }
1009 }
1010 }
1012 static unsigned *done_pbase_paths;
1013 static int done_pbase_paths_num;
1014 static int done_pbase_paths_alloc;
1015 static int done_pbase_path_pos(unsigned hash)
1016 {
1017 int lo = 0;
1018 int hi = done_pbase_paths_num;
1019 while (lo < hi) {
1020 int mi = (hi + lo) / 2;
1021 if (done_pbase_paths[mi] == hash)
1022 return mi;
1023 if (done_pbase_paths[mi] < hash)
1024 hi = mi;
1025 else
1026 lo = mi + 1;
1027 }
1028 return -lo-1;
1029 }
1031 static int check_pbase_path(unsigned hash)
1032 {
1033 int pos = (!done_pbase_paths) ? -1 : done_pbase_path_pos(hash);
1034 if (0 <= pos)
1035 return 1;
1036 pos = -pos - 1;
1037 if (done_pbase_paths_alloc <= done_pbase_paths_num) {
1038 done_pbase_paths_alloc = alloc_nr(done_pbase_paths_alloc);
1039 done_pbase_paths = xrealloc(done_pbase_paths,
1040 done_pbase_paths_alloc *
1041 sizeof(unsigned));
1042 }
1043 done_pbase_paths_num++;
1044 if (pos < done_pbase_paths_num)
1045 memmove(done_pbase_paths + pos + 1,
1046 done_pbase_paths + pos,
1047 (done_pbase_paths_num - pos - 1) * sizeof(unsigned));
1048 done_pbase_paths[pos] = hash;
1049 return 0;
1050 }
1052 static void add_preferred_base_object(const char *name)
1053 {
1054 struct pbase_tree *it;
1055 int cmplen;
1056 unsigned hash = name_hash(name);
1058 if (!num_preferred_base || check_pbase_path(hash))
1059 return;
1061 cmplen = name_cmp_len(name);
1062 for (it = pbase_tree; it; it = it->next) {
1063 if (cmplen == 0) {
1064 add_object_entry(it->pcache.sha1, OBJ_TREE, NULL, 1);
1065 }
1066 else {
1067 struct tree_desc tree;
1068 init_tree_desc(&tree, it->pcache.tree_data, it->pcache.tree_size);
1069 add_pbase_object(&tree, name, cmplen, name);
1070 }
1071 }
1072 }
1074 static void add_preferred_base(unsigned char *sha1)
1075 {
1076 struct pbase_tree *it;
1077 void *data;
1078 unsigned long size;
1079 unsigned char tree_sha1[20];
1081 if (window <= num_preferred_base++)
1082 return;
1084 data = read_object_with_reference(sha1, tree_type, &size, tree_sha1);
1085 if (!data)
1086 return;
1088 for (it = pbase_tree; it; it = it->next) {
1089 if (!hashcmp(it->pcache.sha1, tree_sha1)) {
1090 free(data);
1091 return;
1092 }
1093 }
1095 it = xcalloc(1, sizeof(*it));
1096 it->next = pbase_tree;
1097 pbase_tree = it;
1099 hashcpy(it->pcache.sha1, tree_sha1);
1100 it->pcache.tree_data = data;
1101 it->pcache.tree_size = size;
1102 }
1104 static void check_object(struct object_entry *entry)
1105 {
1106 if (entry->in_pack) {
1107 struct packed_git *p = entry->in_pack;
1108 struct pack_window *w_curs = NULL;
1109 const unsigned char *base_ref = NULL;
1110 struct object_entry *base_entry;
1111 unsigned long used, used_0;
1112 unsigned int avail;
1113 off_t ofs;
1114 unsigned char *buf, c;
1116 buf = use_pack(p, &w_curs, entry->in_pack_offset, &avail);
1118 /*
1119 * We want in_pack_type even if we do not reuse delta
1120 * since non-delta representations could still be reused.
1121 */
1122 used = unpack_object_header_gently(buf, avail,
1123 &entry->in_pack_type,
1124 &entry->size);
1126 /*
1127 * Determine if this is a delta and if so whether we can
1128 * reuse it or not. Otherwise let's find out as cheaply as
1129 * possible what the actual type and size for this object is.
1130 */
1131 switch (entry->in_pack_type) {
1132 default:
1133 /* Not a delta hence we've already got all we need. */
1134 entry->type = entry->in_pack_type;
1135 entry->in_pack_header_size = used;
1136 unuse_pack(&w_curs);
1137 return;
1138 case OBJ_REF_DELTA:
1139 if (!no_reuse_delta && !entry->preferred_base)
1140 base_ref = use_pack(p, &w_curs,
1141 entry->in_pack_offset + used, NULL);
1142 entry->in_pack_header_size = used + 20;
1143 break;
1144 case OBJ_OFS_DELTA:
1145 buf = use_pack(p, &w_curs,
1146 entry->in_pack_offset + used, NULL);
1147 used_0 = 0;
1148 c = buf[used_0++];
1149 ofs = c & 127;
1150 while (c & 128) {
1151 ofs += 1;
1152 if (!ofs || MSB(ofs, 7))
1153 die("delta base offset overflow in pack for %s",
1154 sha1_to_hex(entry->idx.sha1));
1155 c = buf[used_0++];
1156 ofs = (ofs << 7) + (c & 127);
1157 }
1158 if (ofs >= entry->in_pack_offset)
1159 die("delta base offset out of bound for %s",
1160 sha1_to_hex(entry->idx.sha1));
1161 ofs = entry->in_pack_offset - ofs;
1162 if (!no_reuse_delta && !entry->preferred_base)
1163 base_ref = find_packed_object_name(p, ofs);
1164 entry->in_pack_header_size = used + used_0;
1165 break;
1166 }
1168 if (base_ref && (base_entry = locate_object_entry(base_ref))) {
1169 /*
1170 * If base_ref was set above that means we wish to
1171 * reuse delta data, and we even found that base
1172 * in the list of objects we want to pack. Goodie!
1173 *
1174 * Depth value does not matter - find_deltas() will
1175 * never consider reused delta as the base object to
1176 * deltify other objects against, in order to avoid
1177 * circular deltas.
1178 */
1179 entry->type = entry->in_pack_type;
1180 entry->delta = base_entry;
1181 entry->delta_sibling = base_entry->delta_child;
1182 base_entry->delta_child = entry;
1183 unuse_pack(&w_curs);
1184 return;
1185 }
1187 if (entry->type) {
1188 /*
1189 * This must be a delta and we already know what the
1190 * final object type is. Let's extract the actual
1191 * object size from the delta header.
1192 */
1193 entry->size = get_size_from_delta(p, &w_curs,
1194 entry->in_pack_offset + entry->in_pack_header_size);
1195 unuse_pack(&w_curs);
1196 return;
1197 }
1199 /*
1200 * No choice but to fall back to the recursive delta walk
1201 * with sha1_object_info() to find about the object type
1202 * at this point...
1203 */
1204 unuse_pack(&w_curs);
1205 }
1207 entry->type = sha1_object_info(entry->idx.sha1, &entry->size);
1208 if (entry->type < 0)
1209 die("unable to get type of object %s",
1210 sha1_to_hex(entry->idx.sha1));
1211 }
1213 static int pack_offset_sort(const void *_a, const void *_b)
1214 {
1215 const struct object_entry *a = *(struct object_entry **)_a;
1216 const struct object_entry *b = *(struct object_entry **)_b;
1218 /* avoid filesystem trashing with loose objects */
1219 if (!a->in_pack && !b->in_pack)
1220 return hashcmp(a->idx.sha1, b->idx.sha1);
1222 if (a->in_pack < b->in_pack)
1223 return -1;
1224 if (a->in_pack > b->in_pack)
1225 return 1;
1226 return a->in_pack_offset < b->in_pack_offset ? -1 :
1227 (a->in_pack_offset > b->in_pack_offset);
1228 }
1230 static void get_object_details(void)
1231 {
1232 uint32_t i;
1233 struct object_entry **sorted_by_offset;
1235 sorted_by_offset = xcalloc(nr_objects, sizeof(struct object_entry *));
1236 for (i = 0; i < nr_objects; i++)
1237 sorted_by_offset[i] = objects + i;
1238 qsort(sorted_by_offset, nr_objects, sizeof(*sorted_by_offset), pack_offset_sort);
1240 prepare_pack_ix();
1241 for (i = 0; i < nr_objects; i++)
1242 check_object(sorted_by_offset[i]);
1243 free(sorted_by_offset);
1244 }
1246 static int type_size_sort(const void *_a, const void *_b)
1247 {
1248 const struct object_entry *a = *(struct object_entry **)_a;
1249 const struct object_entry *b = *(struct object_entry **)_b;
1251 if (a->type < b->type)
1252 return -1;
1253 if (a->type > b->type)
1254 return 1;
1255 if (a->hash < b->hash)
1256 return -1;
1257 if (a->hash > b->hash)
1258 return 1;
1259 if (a->preferred_base < b->preferred_base)
1260 return -1;
1261 if (a->preferred_base > b->preferred_base)
1262 return 1;
1263 if (a->size < b->size)
1264 return -1;
1265 if (a->size > b->size)
1266 return 1;
1267 return a > b ? -1 : (a < b); /* newest last */
1268 }
1270 struct unpacked {
1271 struct object_entry *entry;
1272 void *data;
1273 struct delta_index *index;
1274 unsigned depth;
1275 };
1277 static int delta_cacheable(unsigned long src_size, unsigned long trg_size,
1278 unsigned long delta_size)
1279 {
1280 if (max_delta_cache_size && delta_cache_size + delta_size > max_delta_cache_size)
1281 return 0;
1283 if (delta_size < cache_max_small_delta_size)
1284 return 1;
1286 /* cache delta, if objects are large enough compared to delta size */
1287 if ((src_size >> 20) + (trg_size >> 21) > (delta_size >> 10))
1288 return 1;
1290 return 0;
1291 }
1293 /*
1294 * We search for deltas _backwards_ in a list sorted by type and
1295 * by size, so that we see progressively smaller and smaller files.
1296 * That's because we prefer deltas to be from the bigger file
1297 * to the smaller - deletes are potentially cheaper, but perhaps
1298 * more importantly, the bigger file is likely the more recent
1299 * one.
1300 */
1301 static int try_delta(struct unpacked *trg, struct unpacked *src,
1302 unsigned max_depth, unsigned long *mem_usage)
1303 {
1304 struct object_entry *trg_entry = trg->entry;
1305 struct object_entry *src_entry = src->entry;
1306 unsigned long trg_size, src_size, delta_size, sizediff, max_size, sz;
1307 unsigned ref_depth;
1308 enum object_type type;
1309 void *delta_buf;
1311 /* Don't bother doing diffs between different types */
1312 if (trg_entry->type != src_entry->type)
1313 return -1;
1315 /*
1316 * We do not bother to try a delta that we discarded
1317 * on an earlier try, but only when reusing delta data.
1318 */
1319 if (!no_reuse_delta && trg_entry->in_pack &&
1320 trg_entry->in_pack == src_entry->in_pack &&
1321 trg_entry->in_pack_type != OBJ_REF_DELTA &&
1322 trg_entry->in_pack_type != OBJ_OFS_DELTA)
1323 return 0;
1325 /* Let's not bust the allowed depth. */
1326 if (src->depth >= max_depth)
1327 return 0;
1329 /* Now some size filtering heuristics. */
1330 trg_size = trg_entry->size;
1331 if (!trg_entry->delta) {
1332 max_size = trg_size/2 - 20;
1333 ref_depth = 1;
1334 } else {
1335 max_size = trg_entry->delta_size;
1336 ref_depth = trg->depth;
1337 }
1338 max_size = max_size * (max_depth - src->depth) /
1339 (max_depth - ref_depth + 1);
1340 if (max_size == 0)
1341 return 0;
1342 src_size = src_entry->size;
1343 sizediff = src_size < trg_size ? trg_size - src_size : 0;
1344 if (sizediff >= max_size)
1345 return 0;
1346 if (trg_size < src_size / 32)
1347 return 0;
1349 /* Load data if not already done */
1350 if (!trg->data) {
1351 trg->data = read_sha1_file(trg_entry->idx.sha1, &type, &sz);
1352 if (!trg->data)
1353 die("object %s cannot be read",
1354 sha1_to_hex(trg_entry->idx.sha1));
1355 if (sz != trg_size)
1356 die("object %s inconsistent object length (%lu vs %lu)",
1357 sha1_to_hex(trg_entry->idx.sha1), sz, trg_size);
1358 *mem_usage += sz;
1359 }
1360 if (!src->data) {
1361 src->data = read_sha1_file(src_entry->idx.sha1, &type, &sz);
1362 if (!src->data)
1363 die("object %s cannot be read",
1364 sha1_to_hex(src_entry->idx.sha1));
1365 if (sz != src_size)
1366 die("object %s inconsistent object length (%lu vs %lu)",
1367 sha1_to_hex(src_entry->idx.sha1), sz, src_size);
1368 *mem_usage += sz;
1369 }
1370 if (!src->index) {
1371 src->index = create_delta_index(src->data, src_size);
1372 if (!src->index) {
1373 static int warned = 0;
1374 if (!warned++)
1375 warning("suboptimal pack - out of memory");
1376 return 0;
1377 }
1378 *mem_usage += sizeof_delta_index(src->index);
1379 }
1381 delta_buf = create_delta(src->index, trg->data, trg_size, &delta_size, max_size);
1382 if (!delta_buf)
1383 return 0;
1385 if (trg_entry->delta) {
1386 /* Prefer only shallower same-sized deltas. */
1387 if (delta_size == trg_entry->delta_size &&
1388 src->depth + 1 >= trg->depth) {
1389 free(delta_buf);
1390 return 0;
1391 }
1392 }
1394 trg_entry->delta = src_entry;
1395 trg_entry->delta_size = delta_size;
1396 trg->depth = src->depth + 1;
1398 if (trg_entry->delta_data) {
1399 delta_cache_size -= trg_entry->delta_size;
1400 free(trg_entry->delta_data);
1401 trg_entry->delta_data = NULL;
1402 }
1404 if (delta_cacheable(src_size, trg_size, delta_size)) {
1405 trg_entry->delta_data = xrealloc(delta_buf, delta_size);
1406 delta_cache_size += trg_entry->delta_size;
1407 } else
1408 free(delta_buf);
1409 return 1;
1410 }
1412 static unsigned int check_delta_limit(struct object_entry *me, unsigned int n)
1413 {
1414 struct object_entry *child = me->delta_child;
1415 unsigned int m = n;
1416 while (child) {
1417 unsigned int c = check_delta_limit(child, n + 1);
1418 if (m < c)
1419 m = c;
1420 child = child->delta_sibling;
1421 }
1422 return m;
1423 }
1425 static unsigned long free_unpacked(struct unpacked *n)
1426 {
1427 unsigned long freed_mem = sizeof_delta_index(n->index);
1428 free_delta_index(n->index);
1429 n->index = NULL;
1430 if (n->data) {
1431 freed_mem += n->entry->size;
1432 free(n->data);
1433 n->data = NULL;
1434 }
1435 n->entry = NULL;
1436 n->depth = 0;
1437 return freed_mem;
1438 }
1440 static void find_deltas(struct object_entry **list, unsigned list_size,
1441 int window, int depth, unsigned *processed)
1442 {
1443 uint32_t i = list_size, idx = 0, count = 0;
1444 unsigned int array_size = window * sizeof(struct unpacked);
1445 struct unpacked *array;
1446 unsigned long mem_usage = 0;
1448 array = xmalloc(array_size);
1449 memset(array, 0, array_size);
1451 do {
1452 struct object_entry *entry = list[--i];
1453 struct unpacked *n = array + idx;
1454 int j, max_depth, best_base = -1;
1456 mem_usage -= free_unpacked(n);
1457 n->entry = entry;
1459 while (window_memory_limit &&
1460 mem_usage > window_memory_limit &&
1461 count > 1) {
1462 uint32_t tail = (idx + window - count) % window;
1463 mem_usage -= free_unpacked(array + tail);
1464 count--;
1465 }
1467 /* We do not compute delta to *create* objects we are not
1468 * going to pack.
1469 */
1470 if (entry->preferred_base)
1471 goto next;
1473 (*processed)++;
1474 if (progress)
1475 display_progress(&progress_state, *processed);
1477 /*
1478 * If the current object is at pack edge, take the depth the
1479 * objects that depend on the current object into account
1480 * otherwise they would become too deep.
1481 */
1482 max_depth = depth;
1483 if (entry->delta_child) {
1484 max_depth -= check_delta_limit(entry, 0);
1485 if (max_depth <= 0)
1486 goto next;
1487 }
1489 j = window;
1490 while (--j > 0) {
1491 int ret;
1492 uint32_t other_idx = idx + j;
1493 struct unpacked *m;
1494 if (other_idx >= window)
1495 other_idx -= window;
1496 m = array + other_idx;
1497 if (!m->entry)
1498 break;
1499 ret = try_delta(n, m, max_depth, &mem_usage);
1500 if (ret < 0)
1501 break;
1502 else if (ret > 0)
1503 best_base = other_idx;
1504 }
1506 /* if we made n a delta, and if n is already at max
1507 * depth, leaving it in the window is pointless. we
1508 * should evict it first.
1509 */
1510 if (entry->delta && depth <= n->depth)
1511 continue;
1513 /*
1514 * Move the best delta base up in the window, after the
1515 * currently deltified object, to keep it longer. It will
1516 * be the first base object to be attempted next.
1517 */
1518 if (entry->delta) {
1519 struct unpacked swap = array[best_base];
1520 int dist = (window + idx - best_base) % window;
1521 int dst = best_base;
1522 while (dist--) {
1523 int src = (dst + 1) % window;
1524 array[dst] = array[src];
1525 dst = src;
1526 }
1527 array[dst] = swap;
1528 }
1530 next:
1531 idx++;
1532 if (count + 1 < window)
1533 count++;
1534 if (idx >= window)
1535 idx = 0;
1536 } while (i > 0);
1538 for (i = 0; i < window; ++i) {
1539 free_delta_index(array[i].index);
1540 free(array[i].data);
1541 }
1542 free(array);
1543 }
1545 static void prepare_pack(int window, int depth)
1546 {
1547 struct object_entry **delta_list;
1548 uint32_t i, n, nr_deltas;
1550 get_object_details();
1552 if (!nr_objects || !window || !depth)
1553 return;
1555 delta_list = xmalloc(nr_objects * sizeof(*delta_list));
1556 nr_deltas = n = 0;
1558 for (i = 0; i < nr_objects; i++) {
1559 struct object_entry *entry = objects + i;
1561 if (entry->delta)
1562 /* This happens if we decided to reuse existing
1563 * delta from a pack. "!no_reuse_delta &&" is implied.
1564 */
1565 continue;
1567 if (entry->size < 50)
1568 continue;
1570 if (entry->no_try_delta)
1571 continue;
1573 if (!entry->preferred_base)
1574 nr_deltas++;
1576 delta_list[n++] = entry;
1577 }
1579 if (nr_deltas) {
1580 unsigned nr_done = 0;
1581 if (progress)
1582 start_progress(&progress_state,
1583 "Deltifying %u objects...", "",
1584 nr_deltas);
1585 qsort(delta_list, n, sizeof(*delta_list), type_size_sort);
1586 find_deltas(delta_list, n, window+1, depth, &nr_done);
1587 if (progress)
1588 stop_progress(&progress_state);
1589 if (nr_done != nr_deltas)
1590 die("inconsistency with delta count");
1591 }
1592 free(delta_list);
1593 }
1595 static int git_pack_config(const char *k, const char *v)
1596 {
1597 if(!strcmp(k, "pack.window")) {
1598 window = git_config_int(k, v);
1599 return 0;
1600 }
1601 if (!strcmp(k, "pack.windowmemory")) {
1602 window_memory_limit = git_config_ulong(k, v);
1603 return 0;
1604 }
1605 if (!strcmp(k, "pack.depth")) {
1606 depth = git_config_int(k, v);
1607 return 0;
1608 }
1609 if (!strcmp(k, "pack.compression")) {
1610 int level = git_config_int(k, v);
1611 if (level == -1)
1612 level = Z_DEFAULT_COMPRESSION;
1613 else if (level < 0 || level > Z_BEST_COMPRESSION)
1614 die("bad pack compression level %d", level);
1615 pack_compression_level = level;
1616 pack_compression_seen = 1;
1617 return 0;
1618 }
1619 if (!strcmp(k, "pack.deltacachesize")) {
1620 max_delta_cache_size = git_config_int(k, v);
1621 return 0;
1622 }
1623 if (!strcmp(k, "pack.deltacachelimit")) {
1624 cache_max_small_delta_size = git_config_int(k, v);
1625 return 0;
1626 }
1627 return git_default_config(k, v);
1628 }
1630 static void read_object_list_from_stdin(void)
1631 {
1632 char line[40 + 1 + PATH_MAX + 2];
1633 unsigned char sha1[20];
1635 for (;;) {
1636 if (!fgets(line, sizeof(line), stdin)) {
1637 if (feof(stdin))
1638 break;
1639 if (!ferror(stdin))
1640 die("fgets returned NULL, not EOF, not error!");
1641 if (errno != EINTR)
1642 die("fgets: %s", strerror(errno));
1643 clearerr(stdin);
1644 continue;
1645 }
1646 if (line[0] == '-') {
1647 if (get_sha1_hex(line+1, sha1))
1648 die("expected edge sha1, got garbage:\n %s",
1649 line);
1650 add_preferred_base(sha1);
1651 continue;
1652 }
1653 if (get_sha1_hex(line, sha1))
1654 die("expected sha1, got garbage:\n %s", line);
1656 add_preferred_base_object(line+41);
1657 add_object_entry(sha1, 0, line+41, 0);
1658 }
1659 }
1661 static void show_commit(struct commit *commit)
1662 {
1663 add_object_entry(commit->object.sha1, OBJ_COMMIT, NULL, 0);
1664 }
1666 static void show_object(struct object_array_entry *p)
1667 {
1668 add_preferred_base_object(p->name);
1669 add_object_entry(p->item->sha1, p->item->type, p->name, 0);
1670 }
1672 static void show_edge(struct commit *commit)
1673 {
1674 add_preferred_base(commit->object.sha1);
1675 }
1677 static void get_object_list(int ac, const char **av)
1678 {
1679 struct rev_info revs;
1680 char line[1000];
1681 int flags = 0;
1683 init_revisions(&revs, NULL);
1684 save_commit_buffer = 0;
1685 track_object_refs = 0;
1686 setup_revisions(ac, av, &revs, NULL);
1688 while (fgets(line, sizeof(line), stdin) != NULL) {
1689 int len = strlen(line);
1690 if (line[len - 1] == '\n')
1691 line[--len] = 0;
1692 if (!len)
1693 break;
1694 if (*line == '-') {
1695 if (!strcmp(line, "--not")) {
1696 flags ^= UNINTERESTING;
1697 continue;
1698 }
1699 die("not a rev '%s'", line);
1700 }
1701 if (handle_revision_arg(line, &revs, flags, 1))
1702 die("bad revision '%s'", line);
1703 }
1705 prepare_revision_walk(&revs);
1706 mark_edges_uninteresting(revs.commits, &revs, show_edge);
1707 traverse_commit_list(&revs, show_commit, show_object);
1708 }
1710 static int adjust_perm(const char *path, mode_t mode)
1711 {
1712 if (chmod(path, mode))
1713 return -1;
1714 return adjust_shared_perm(path);
1715 }
1717 int cmd_pack_objects(int argc, const char **argv, const char *prefix)
1718 {
1719 int use_internal_rev_list = 0;
1720 int thin = 0;
1721 uint32_t i;
1722 const char **rp_av;
1723 int rp_ac_alloc = 64;
1724 int rp_ac;
1726 rp_av = xcalloc(rp_ac_alloc, sizeof(*rp_av));
1728 rp_av[0] = "pack-objects";
1729 rp_av[1] = "--objects"; /* --thin will make it --objects-edge */
1730 rp_ac = 2;
1732 git_config(git_pack_config);
1733 if (!pack_compression_seen && core_compression_seen)
1734 pack_compression_level = core_compression_level;
1736 progress = isatty(2);
1737 for (i = 1; i < argc; i++) {
1738 const char *arg = argv[i];
1740 if (*arg != '-')
1741 break;
1743 if (!strcmp("--non-empty", arg)) {
1744 non_empty = 1;
1745 continue;
1746 }
1747 if (!strcmp("--local", arg)) {
1748 local = 1;
1749 continue;
1750 }
1751 if (!strcmp("--incremental", arg)) {
1752 incremental = 1;
1753 continue;
1754 }
1755 if (!prefixcmp(arg, "--compression=")) {
1756 char *end;
1757 int level = strtoul(arg+14, &end, 0);
1758 if (!arg[14] || *end)
1759 usage(pack_usage);
1760 if (level == -1)
1761 level = Z_DEFAULT_COMPRESSION;
1762 else if (level < 0 || level > Z_BEST_COMPRESSION)
1763 die("bad pack compression level %d", level);
1764 pack_compression_level = level;
1765 continue;
1766 }
1767 if (!prefixcmp(arg, "--max-pack-size=")) {
1768 char *end;
1769 pack_size_limit = strtoul(arg+16, &end, 0) * 1024 * 1024;
1770 if (!arg[16] || *end)
1771 usage(pack_usage);
1772 continue;
1773 }
1774 if (!prefixcmp(arg, "--window=")) {
1775 char *end;
1776 window = strtoul(arg+9, &end, 0);
1777 if (!arg[9] || *end)
1778 usage(pack_usage);
1779 continue;
1780 }
1781 if (!prefixcmp(arg, "--window-memory=")) {
1782 if (!git_parse_ulong(arg+16, &window_memory_limit))
1783 usage(pack_usage);
1784 continue;
1785 }
1786 if (!prefixcmp(arg, "--depth=")) {
1787 char *end;
1788 depth = strtoul(arg+8, &end, 0);
1789 if (!arg[8] || *end)
1790 usage(pack_usage);
1791 continue;
1792 }
1793 if (!strcmp("--progress", arg)) {
1794 progress = 1;
1795 continue;
1796 }
1797 if (!strcmp("--all-progress", arg)) {
1798 progress = 2;
1799 continue;
1800 }
1801 if (!strcmp("-q", arg)) {
1802 progress = 0;
1803 continue;
1804 }
1805 if (!strcmp("--no-reuse-delta", arg)) {
1806 no_reuse_delta = 1;
1807 continue;
1808 }
1809 if (!strcmp("--no-reuse-object", arg)) {
1810 no_reuse_object = no_reuse_delta = 1;
1811 continue;
1812 }
1813 if (!strcmp("--delta-base-offset", arg)) {
1814 allow_ofs_delta = 1;
1815 continue;
1816 }
1817 if (!strcmp("--stdout", arg)) {
1818 pack_to_stdout = 1;
1819 continue;
1820 }
1821 if (!strcmp("--revs", arg)) {
1822 use_internal_rev_list = 1;
1823 continue;
1824 }
1825 if (!strcmp("--unpacked", arg) ||
1826 !prefixcmp(arg, "--unpacked=") ||
1827 !strcmp("--reflog", arg) ||
1828 !strcmp("--all", arg)) {
1829 use_internal_rev_list = 1;
1830 if (rp_ac >= rp_ac_alloc - 1) {
1831 rp_ac_alloc = alloc_nr(rp_ac_alloc);
1832 rp_av = xrealloc(rp_av,
1833 rp_ac_alloc * sizeof(*rp_av));
1834 }
1835 rp_av[rp_ac++] = arg;
1836 continue;
1837 }
1838 if (!strcmp("--thin", arg)) {
1839 use_internal_rev_list = 1;
1840 thin = 1;
1841 rp_av[1] = "--objects-edge";
1842 continue;
1843 }
1844 if (!prefixcmp(arg, "--index-version=")) {
1845 char *c;
1846 pack_idx_default_version = strtoul(arg + 16, &c, 10);
1847 if (pack_idx_default_version > 2)
1848 die("bad %s", arg);
1849 if (*c == ',')
1850 pack_idx_off32_limit = strtoul(c+1, &c, 0);
1851 if (*c || pack_idx_off32_limit & 0x80000000)
1852 die("bad %s", arg);
1853 continue;
1854 }
1855 usage(pack_usage);
1856 }
1858 /* Traditionally "pack-objects [options] base extra" failed;
1859 * we would however want to take refs parameter that would
1860 * have been given to upstream rev-list ourselves, which means
1861 * we somehow want to say what the base name is. So the
1862 * syntax would be:
1863 *
1864 * pack-objects [options] base <refs...>
1865 *
1866 * in other words, we would treat the first non-option as the
1867 * base_name and send everything else to the internal revision
1868 * walker.
1869 */
1871 if (!pack_to_stdout)
1872 base_name = argv[i++];
1874 if (pack_to_stdout != !base_name)
1875 usage(pack_usage);
1877 if (pack_to_stdout && pack_size_limit)
1878 die("--max-pack-size cannot be used to build a pack for transfer.");
1880 if (!pack_to_stdout && thin)
1881 die("--thin cannot be used to build an indexable pack.");
1883 prepare_packed_git();
1885 if (progress)
1886 start_progress(&progress_state, "Generating pack...",
1887 "Counting objects: ", 0);
1888 if (!use_internal_rev_list)
1889 read_object_list_from_stdin();
1890 else {
1891 rp_av[rp_ac] = NULL;
1892 get_object_list(rp_ac, rp_av);
1893 }
1894 if (progress) {
1895 stop_progress(&progress_state);
1896 fprintf(stderr, "Done counting %u objects.\n", nr_objects);
1897 }
1899 if (non_empty && !nr_result)
1900 return 0;
1901 if (progress && (nr_objects != nr_result))
1902 fprintf(stderr, "Result has %u objects.\n", nr_result);
1903 if (nr_result)
1904 prepare_pack(window, depth);
1905 write_pack_file();
1906 if (progress)
1907 fprintf(stderr, "Total %u (delta %u), reused %u (delta %u)\n",
1908 written, written_delta, reused, reused_delta);
1909 return 0;
1910 }