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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_usage = 0;
82 static unsigned long window_memory_limit = 0;
84 /*
85 * The object names in objects array are hashed with this hashtable,
86 * to help looking up the entry by object name.
87 * This hashtable is built after all the objects are seen.
88 */
89 static int *object_ix;
90 static int object_ix_hashsz;
92 /*
93 * Pack index for existing packs give us easy access to the offsets into
94 * corresponding pack file where each object's data starts, but the entries
95 * do not store the size of the compressed representation (uncompressed
96 * size is easily available by examining the pack entry header). It is
97 * also rather expensive to find the sha1 for an object given its offset.
98 *
99 * We build a hashtable of existing packs (pack_revindex), and keep reverse
100 * index here -- pack index file is sorted by object name mapping to offset;
101 * this pack_revindex[].revindex array is a list of offset/index_nr pairs
102 * ordered by offset, so if you know the offset of an object, next offset
103 * is where its packed representation ends and the index_nr can be used to
104 * get the object sha1 from the main index.
105 */
106 struct revindex_entry {
107 off_t offset;
108 unsigned int nr;
109 };
110 struct pack_revindex {
111 struct packed_git *p;
112 struct revindex_entry *revindex;
113 };
114 static struct pack_revindex *pack_revindex;
115 static int pack_revindex_hashsz;
117 /*
118 * stats
119 */
120 static uint32_t written, written_delta;
121 static uint32_t reused, reused_delta;
123 static int pack_revindex_ix(struct packed_git *p)
124 {
125 unsigned long ui = (unsigned long)p;
126 int i;
128 ui = ui ^ (ui >> 16); /* defeat structure alignment */
129 i = (int)(ui % pack_revindex_hashsz);
130 while (pack_revindex[i].p) {
131 if (pack_revindex[i].p == p)
132 return i;
133 if (++i == pack_revindex_hashsz)
134 i = 0;
135 }
136 return -1 - i;
137 }
139 static void prepare_pack_ix(void)
140 {
141 int num;
142 struct packed_git *p;
143 for (num = 0, p = packed_git; p; p = p->next)
144 num++;
145 if (!num)
146 return;
147 pack_revindex_hashsz = num * 11;
148 pack_revindex = xcalloc(sizeof(*pack_revindex), pack_revindex_hashsz);
149 for (p = packed_git; p; p = p->next) {
150 num = pack_revindex_ix(p);
151 num = - 1 - num;
152 pack_revindex[num].p = p;
153 }
154 /* revindex elements are lazily initialized */
155 }
157 static int cmp_offset(const void *a_, const void *b_)
158 {
159 const struct revindex_entry *a = a_;
160 const struct revindex_entry *b = b_;
161 return (a->offset < b->offset) ? -1 : (a->offset > b->offset) ? 1 : 0;
162 }
164 /*
165 * Ordered list of offsets of objects in the pack.
166 */
167 static void prepare_pack_revindex(struct pack_revindex *rix)
168 {
169 struct packed_git *p = rix->p;
170 int num_ent = p->num_objects;
171 int i;
172 const char *index = p->index_data;
174 rix->revindex = xmalloc(sizeof(*rix->revindex) * (num_ent + 1));
175 index += 4 * 256;
177 if (p->index_version > 1) {
178 const uint32_t *off_32 =
179 (uint32_t *)(index + 8 + p->num_objects * (20 + 4));
180 const uint32_t *off_64 = off_32 + p->num_objects;
181 for (i = 0; i < num_ent; i++) {
182 uint32_t off = ntohl(*off_32++);
183 if (!(off & 0x80000000)) {
184 rix->revindex[i].offset = off;
185 } else {
186 rix->revindex[i].offset =
187 ((uint64_t)ntohl(*off_64++)) << 32;
188 rix->revindex[i].offset |=
189 ntohl(*off_64++);
190 }
191 rix->revindex[i].nr = i;
192 }
193 } else {
194 for (i = 0; i < num_ent; i++) {
195 uint32_t hl = *((uint32_t *)(index + 24 * i));
196 rix->revindex[i].offset = ntohl(hl);
197 rix->revindex[i].nr = i;
198 }
199 }
201 /* This knows the pack format -- the 20-byte trailer
202 * follows immediately after the last object data.
203 */
204 rix->revindex[num_ent].offset = p->pack_size - 20;
205 rix->revindex[num_ent].nr = -1;
206 qsort(rix->revindex, num_ent, sizeof(*rix->revindex), cmp_offset);
207 }
209 static struct revindex_entry * find_packed_object(struct packed_git *p,
210 off_t ofs)
211 {
212 int num;
213 int lo, hi;
214 struct pack_revindex *rix;
215 struct revindex_entry *revindex;
216 num = pack_revindex_ix(p);
217 if (num < 0)
218 die("internal error: pack revindex uninitialized");
219 rix = &pack_revindex[num];
220 if (!rix->revindex)
221 prepare_pack_revindex(rix);
222 revindex = rix->revindex;
223 lo = 0;
224 hi = p->num_objects + 1;
225 do {
226 int mi = (lo + hi) / 2;
227 if (revindex[mi].offset == ofs) {
228 return revindex + mi;
229 }
230 else if (ofs < revindex[mi].offset)
231 hi = mi;
232 else
233 lo = mi + 1;
234 } while (lo < hi);
235 die("internal error: pack revindex corrupt");
236 }
238 static const unsigned char *find_packed_object_name(struct packed_git *p,
239 off_t ofs)
240 {
241 struct revindex_entry *entry = find_packed_object(p, ofs);
242 return nth_packed_object_sha1(p, entry->nr);
243 }
245 static void *delta_against(void *buf, unsigned long size, struct object_entry *entry)
246 {
247 unsigned long othersize, delta_size;
248 enum object_type type;
249 void *otherbuf = read_sha1_file(entry->delta->idx.sha1, &type, &othersize);
250 void *delta_buf;
252 if (!otherbuf)
253 die("unable to read %s", sha1_to_hex(entry->delta->idx.sha1));
254 delta_buf = diff_delta(otherbuf, othersize,
255 buf, size, &delta_size, 0);
256 if (!delta_buf || delta_size != entry->delta_size)
257 die("delta size changed");
258 free(buf);
259 free(otherbuf);
260 return delta_buf;
261 }
263 /*
264 * The per-object header is a pretty dense thing, which is
265 * - first byte: low four bits are "size", then three bits of "type",
266 * and the high bit is "size continues".
267 * - each byte afterwards: low seven bits are size continuation,
268 * with the high bit being "size continues"
269 */
270 static int encode_header(enum object_type type, unsigned long size, unsigned char *hdr)
271 {
272 int n = 1;
273 unsigned char c;
275 if (type < OBJ_COMMIT || type > OBJ_REF_DELTA)
276 die("bad type %d", type);
278 c = (type << 4) | (size & 15);
279 size >>= 4;
280 while (size) {
281 *hdr++ = c | 0x80;
282 c = size & 0x7f;
283 size >>= 7;
284 n++;
285 }
286 *hdr = c;
287 return n;
288 }
290 /*
291 * we are going to reuse the existing object data as is. make
292 * sure it is not corrupt.
293 */
294 static int check_pack_inflate(struct packed_git *p,
295 struct pack_window **w_curs,
296 off_t offset,
297 off_t len,
298 unsigned long expect)
299 {
300 z_stream stream;
301 unsigned char fakebuf[4096], *in;
302 int st;
304 memset(&stream, 0, sizeof(stream));
305 inflateInit(&stream);
306 do {
307 in = use_pack(p, w_curs, offset, &stream.avail_in);
308 stream.next_in = in;
309 stream.next_out = fakebuf;
310 stream.avail_out = sizeof(fakebuf);
311 st = inflate(&stream, Z_FINISH);
312 offset += stream.next_in - in;
313 } while (st == Z_OK || st == Z_BUF_ERROR);
314 inflateEnd(&stream);
315 return (st == Z_STREAM_END &&
316 stream.total_out == expect &&
317 stream.total_in == len) ? 0 : -1;
318 }
320 static int check_pack_crc(struct packed_git *p, struct pack_window **w_curs,
321 off_t offset, off_t len, unsigned int nr)
322 {
323 const uint32_t *index_crc;
324 uint32_t data_crc = crc32(0, Z_NULL, 0);
326 do {
327 unsigned int avail;
328 void *data = use_pack(p, w_curs, offset, &avail);
329 if (avail > len)
330 avail = len;
331 data_crc = crc32(data_crc, data, avail);
332 offset += avail;
333 len -= avail;
334 } while (len);
336 index_crc = p->index_data;
337 index_crc += 2 + 256 + p->num_objects * (20/4) + nr;
339 return data_crc != ntohl(*index_crc);
340 }
342 static void copy_pack_data(struct sha1file *f,
343 struct packed_git *p,
344 struct pack_window **w_curs,
345 off_t offset,
346 off_t len)
347 {
348 unsigned char *in;
349 unsigned int avail;
351 while (len) {
352 in = use_pack(p, w_curs, offset, &avail);
353 if (avail > len)
354 avail = (unsigned int)len;
355 sha1write(f, in, avail);
356 offset += avail;
357 len -= avail;
358 }
359 }
361 static unsigned long write_object(struct sha1file *f,
362 struct object_entry *entry,
363 off_t write_offset)
364 {
365 unsigned long size;
366 enum object_type type;
367 void *buf;
368 unsigned char header[10];
369 unsigned char dheader[10];
370 unsigned hdrlen;
371 off_t datalen;
372 enum object_type obj_type;
373 int to_reuse = 0;
374 /* write limit if limited packsize and not first object */
375 unsigned long limit = pack_size_limit && nr_written ?
376 pack_size_limit - write_offset : 0;
377 /* no if no delta */
378 int usable_delta = !entry->delta ? 0 :
379 /* yes if unlimited packfile */
380 !pack_size_limit ? 1 :
381 /* no if base written to previous pack */
382 entry->delta->idx.offset == (off_t)-1 ? 0 :
383 /* otherwise double-check written to this
384 * pack, like we do below
385 */
386 entry->delta->idx.offset ? 1 : 0;
388 if (!pack_to_stdout)
389 crc32_begin(f);
391 obj_type = entry->type;
392 if (no_reuse_object)
393 to_reuse = 0; /* explicit */
394 else if (!entry->in_pack)
395 to_reuse = 0; /* can't reuse what we don't have */
396 else if (obj_type == OBJ_REF_DELTA || obj_type == OBJ_OFS_DELTA)
397 /* check_object() decided it for us ... */
398 to_reuse = usable_delta;
399 /* ... but pack split may override that */
400 else if (obj_type != entry->in_pack_type)
401 to_reuse = 0; /* pack has delta which is unusable */
402 else if (entry->delta)
403 to_reuse = 0; /* we want to pack afresh */
404 else
405 to_reuse = 1; /* we have it in-pack undeltified,
406 * and we do not need to deltify it.
407 */
409 if (!to_reuse) {
410 z_stream stream;
411 unsigned long maxsize;
412 void *out;
413 if (!usable_delta) {
414 buf = read_sha1_file(entry->idx.sha1, &obj_type, &size);
415 if (!buf)
416 die("unable to read %s", sha1_to_hex(entry->idx.sha1));
417 } else if (entry->delta_data) {
418 size = entry->delta_size;
419 buf = entry->delta_data;
420 entry->delta_data = NULL;
421 obj_type = (allow_ofs_delta && entry->delta->idx.offset) ?
422 OBJ_OFS_DELTA : OBJ_REF_DELTA;
423 } else {
424 buf = read_sha1_file(entry->idx.sha1, &type, &size);
425 if (!buf)
426 die("unable to read %s", sha1_to_hex(entry->idx.sha1));
427 buf = delta_against(buf, size, entry);
428 size = entry->delta_size;
429 obj_type = (allow_ofs_delta && entry->delta->idx.offset) ?
430 OBJ_OFS_DELTA : OBJ_REF_DELTA;
431 }
432 /* compress the data to store and put compressed length in datalen */
433 memset(&stream, 0, sizeof(stream));
434 deflateInit(&stream, pack_compression_level);
435 maxsize = deflateBound(&stream, size);
436 out = xmalloc(maxsize);
437 /* Compress it */
438 stream.next_in = buf;
439 stream.avail_in = size;
440 stream.next_out = out;
441 stream.avail_out = maxsize;
442 while (deflate(&stream, Z_FINISH) == Z_OK)
443 /* nothing */;
444 deflateEnd(&stream);
445 datalen = stream.total_out;
446 deflateEnd(&stream);
447 /*
448 * The object header is a byte of 'type' followed by zero or
449 * more bytes of length.
450 */
451 hdrlen = encode_header(obj_type, size, header);
453 if (obj_type == OBJ_OFS_DELTA) {
454 /*
455 * Deltas with relative base contain an additional
456 * encoding of the relative offset for the delta
457 * base from this object's position in the pack.
458 */
459 off_t ofs = entry->idx.offset - entry->delta->idx.offset;
460 unsigned pos = sizeof(dheader) - 1;
461 dheader[pos] = ofs & 127;
462 while (ofs >>= 7)
463 dheader[--pos] = 128 | (--ofs & 127);
464 if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit) {
465 free(out);
466 free(buf);
467 return 0;
468 }
469 sha1write(f, header, hdrlen);
470 sha1write(f, dheader + pos, sizeof(dheader) - pos);
471 hdrlen += sizeof(dheader) - pos;
472 } else if (obj_type == OBJ_REF_DELTA) {
473 /*
474 * Deltas with a base reference contain
475 * an additional 20 bytes for the base sha1.
476 */
477 if (limit && hdrlen + 20 + datalen + 20 >= limit) {
478 free(out);
479 free(buf);
480 return 0;
481 }
482 sha1write(f, header, hdrlen);
483 sha1write(f, entry->delta->idx.sha1, 20);
484 hdrlen += 20;
485 } else {
486 if (limit && hdrlen + datalen + 20 >= limit) {
487 free(out);
488 free(buf);
489 return 0;
490 }
491 sha1write(f, header, hdrlen);
492 }
493 sha1write(f, out, datalen);
494 free(out);
495 free(buf);
496 }
497 else {
498 struct packed_git *p = entry->in_pack;
499 struct pack_window *w_curs = NULL;
500 struct revindex_entry *revidx;
501 off_t offset;
503 if (entry->delta) {
504 obj_type = (allow_ofs_delta && entry->delta->idx.offset) ?
505 OBJ_OFS_DELTA : OBJ_REF_DELTA;
506 reused_delta++;
507 }
508 hdrlen = encode_header(obj_type, entry->size, header);
509 offset = entry->in_pack_offset;
510 revidx = find_packed_object(p, offset);
511 datalen = revidx[1].offset - offset;
512 if (!pack_to_stdout && p->index_version > 1 &&
513 check_pack_crc(p, &w_curs, offset, datalen, revidx->nr))
514 die("bad packed object CRC for %s", sha1_to_hex(entry->idx.sha1));
515 offset += entry->in_pack_header_size;
516 datalen -= entry->in_pack_header_size;
517 if (obj_type == OBJ_OFS_DELTA) {
518 off_t ofs = entry->idx.offset - entry->delta->idx.offset;
519 unsigned pos = sizeof(dheader) - 1;
520 dheader[pos] = ofs & 127;
521 while (ofs >>= 7)
522 dheader[--pos] = 128 | (--ofs & 127);
523 if (limit && hdrlen + sizeof(dheader) - pos + datalen + 20 >= limit)
524 return 0;
525 sha1write(f, header, hdrlen);
526 sha1write(f, dheader + pos, sizeof(dheader) - pos);
527 hdrlen += sizeof(dheader) - pos;
528 } else if (obj_type == OBJ_REF_DELTA) {
529 if (limit && hdrlen + 20 + datalen + 20 >= limit)
530 return 0;
531 sha1write(f, header, hdrlen);
532 sha1write(f, entry->delta->idx.sha1, 20);
533 hdrlen += 20;
534 } else {
535 if (limit && hdrlen + datalen + 20 >= limit)
536 return 0;
537 sha1write(f, header, hdrlen);
538 }
540 if (!pack_to_stdout && p->index_version == 1 &&
541 check_pack_inflate(p, &w_curs, offset, datalen, entry->size))
542 die("corrupt packed object for %s", sha1_to_hex(entry->idx.sha1));
543 copy_pack_data(f, p, &w_curs, offset, datalen);
544 unuse_pack(&w_curs);
545 reused++;
546 }
547 if (usable_delta)
548 written_delta++;
549 written++;
550 if (!pack_to_stdout)
551 entry->idx.crc32 = crc32_end(f);
552 return hdrlen + datalen;
553 }
555 static off_t write_one(struct sha1file *f,
556 struct object_entry *e,
557 off_t offset)
558 {
559 unsigned long size;
561 /* offset is non zero if object is written already. */
562 if (e->idx.offset || e->preferred_base)
563 return offset;
565 /* if we are deltified, write out base object first. */
566 if (e->delta) {
567 offset = write_one(f, e->delta, offset);
568 if (!offset)
569 return 0;
570 }
572 e->idx.offset = offset;
573 size = write_object(f, e, offset);
574 if (!size) {
575 e->idx.offset = 0;
576 return 0;
577 }
578 written_list[nr_written++] = e;
580 /* make sure off_t is sufficiently large not to wrap */
581 if (offset > offset + size)
582 die("pack too large for current definition of off_t");
583 return offset + size;
584 }
586 static int open_object_dir_tmp(const char *path)
587 {
588 snprintf(tmpname, sizeof(tmpname), "%s/%s", get_object_directory(), path);
589 return mkstemp(tmpname);
590 }
592 /* forward declaration for write_pack_file */
593 static int adjust_perm(const char *path, mode_t mode);
595 static void write_pack_file(void)
596 {
597 uint32_t i = 0, j;
598 struct sha1file *f;
599 off_t offset, offset_one, last_obj_offset = 0;
600 struct pack_header hdr;
601 int do_progress = progress >> pack_to_stdout;
602 uint32_t nr_remaining = nr_result;
604 if (do_progress)
605 start_progress(&progress_state, "Writing %u objects...", "", nr_result);
606 written_list = xmalloc(nr_objects * sizeof(struct object_entry *));
608 do {
609 unsigned char sha1[20];
611 if (pack_to_stdout) {
612 f = sha1fd(1, "<stdout>");
613 } else {
614 int fd = open_object_dir_tmp("tmp_pack_XXXXXX");
615 if (fd < 0)
616 die("unable to create %s: %s\n", tmpname, strerror(errno));
617 pack_tmp_name = xstrdup(tmpname);
618 f = sha1fd(fd, pack_tmp_name);
619 }
621 hdr.hdr_signature = htonl(PACK_SIGNATURE);
622 hdr.hdr_version = htonl(PACK_VERSION);
623 hdr.hdr_entries = htonl(nr_remaining);
624 sha1write(f, &hdr, sizeof(hdr));
625 offset = sizeof(hdr);
626 nr_written = 0;
627 for (; i < nr_objects; i++) {
628 last_obj_offset = offset;
629 offset_one = write_one(f, objects + i, offset);
630 if (!offset_one)
631 break;
632 offset = offset_one;
633 if (do_progress)
634 display_progress(&progress_state, written);
635 }
637 /*
638 * Did we write the wrong # entries in the header?
639 * If so, rewrite it like in fast-import
640 */
641 if (pack_to_stdout || nr_written == nr_remaining) {
642 sha1close(f, sha1, 1);
643 } else {
644 sha1close(f, sha1, 0);
645 fixup_pack_header_footer(f->fd, sha1, pack_tmp_name, nr_written);
646 close(f->fd);
647 }
649 if (!pack_to_stdout) {
650 mode_t mode = umask(0);
652 umask(mode);
653 mode = 0444 & ~mode;
655 idx_tmp_name = write_idx_file(NULL,
656 (struct pack_idx_entry **) written_list, nr_written, sha1);
657 snprintf(tmpname, sizeof(tmpname), "%s-%s.pack",
658 base_name, sha1_to_hex(sha1));
659 if (adjust_perm(pack_tmp_name, mode))
660 die("unable to make temporary pack file readable: %s",
661 strerror(errno));
662 if (rename(pack_tmp_name, tmpname))
663 die("unable to rename temporary pack file: %s",
664 strerror(errno));
665 snprintf(tmpname, sizeof(tmpname), "%s-%s.idx",
666 base_name, sha1_to_hex(sha1));
667 if (adjust_perm(idx_tmp_name, mode))
668 die("unable to make temporary index file readable: %s",
669 strerror(errno));
670 if (rename(idx_tmp_name, tmpname))
671 die("unable to rename temporary index file: %s",
672 strerror(errno));
673 puts(sha1_to_hex(sha1));
674 }
676 /* mark written objects as written to previous pack */
677 for (j = 0; j < nr_written; j++) {
678 written_list[j]->idx.offset = (off_t)-1;
679 }
680 nr_remaining -= nr_written;
681 } while (nr_remaining && i < nr_objects);
683 free(written_list);
684 if (do_progress)
685 stop_progress(&progress_state);
686 if (written != nr_result)
687 die("wrote %u objects while expecting %u", written, nr_result);
688 /*
689 * We have scanned through [0 ... i). Since we have written
690 * the correct number of objects, the remaining [i ... nr_objects)
691 * items must be either already written (due to out-of-order delta base)
692 * or a preferred base. Count those which are neither and complain if any.
693 */
694 for (j = 0; i < nr_objects; i++) {
695 struct object_entry *e = objects + i;
696 j += !e->idx.offset && !e->preferred_base;
697 }
698 if (j)
699 die("wrote %u objects as expected but %u unwritten", written, j);
700 }
702 static int locate_object_entry_hash(const unsigned char *sha1)
703 {
704 int i;
705 unsigned int ui;
706 memcpy(&ui, sha1, sizeof(unsigned int));
707 i = ui % object_ix_hashsz;
708 while (0 < object_ix[i]) {
709 if (!hashcmp(sha1, objects[object_ix[i] - 1].idx.sha1))
710 return i;
711 if (++i == object_ix_hashsz)
712 i = 0;
713 }
714 return -1 - i;
715 }
717 static struct object_entry *locate_object_entry(const unsigned char *sha1)
718 {
719 int i;
721 if (!object_ix_hashsz)
722 return NULL;
724 i = locate_object_entry_hash(sha1);
725 if (0 <= i)
726 return &objects[object_ix[i]-1];
727 return NULL;
728 }
730 static void rehash_objects(void)
731 {
732 uint32_t i;
733 struct object_entry *oe;
735 object_ix_hashsz = nr_objects * 3;
736 if (object_ix_hashsz < 1024)
737 object_ix_hashsz = 1024;
738 object_ix = xrealloc(object_ix, sizeof(int) * object_ix_hashsz);
739 memset(object_ix, 0, sizeof(int) * object_ix_hashsz);
740 for (i = 0, oe = objects; i < nr_objects; i++, oe++) {
741 int ix = locate_object_entry_hash(oe->idx.sha1);
742 if (0 <= ix)
743 continue;
744 ix = -1 - ix;
745 object_ix[ix] = i + 1;
746 }
747 }
749 static unsigned name_hash(const char *name)
750 {
751 unsigned char c;
752 unsigned hash = 0;
754 if (!name)
755 return 0;
757 /*
758 * This effectively just creates a sortable number from the
759 * last sixteen non-whitespace characters. Last characters
760 * count "most", so things that end in ".c" sort together.
761 */
762 while ((c = *name++) != 0) {
763 if (isspace(c))
764 continue;
765 hash = (hash >> 2) + (c << 24);
766 }
767 return hash;
768 }
770 static void setup_delta_attr_check(struct git_attr_check *check)
771 {
772 static struct git_attr *attr_delta;
774 if (!attr_delta)
775 attr_delta = git_attr("delta", 5);
777 check[0].attr = attr_delta;
778 }
780 static int no_try_delta(const char *path)
781 {
782 struct git_attr_check check[1];
784 setup_delta_attr_check(check);
785 if (git_checkattr(path, ARRAY_SIZE(check), check))
786 return 0;
787 if (ATTR_FALSE(check->value))
788 return 1;
789 return 0;
790 }
792 static int add_object_entry(const unsigned char *sha1, enum object_type type,
793 const char *name, int exclude)
794 {
795 struct object_entry *entry;
796 struct packed_git *p, *found_pack = NULL;
797 off_t found_offset = 0;
798 int ix;
799 unsigned hash = name_hash(name);
801 ix = nr_objects ? locate_object_entry_hash(sha1) : -1;
802 if (ix >= 0) {
803 if (exclude) {
804 entry = objects + object_ix[ix] - 1;
805 if (!entry->preferred_base)
806 nr_result--;
807 entry->preferred_base = 1;
808 }
809 return 0;
810 }
812 for (p = packed_git; p; p = p->next) {
813 off_t offset = find_pack_entry_one(sha1, p);
814 if (offset) {
815 if (!found_pack) {
816 found_offset = offset;
817 found_pack = p;
818 }
819 if (exclude)
820 break;
821 if (incremental)
822 return 0;
823 if (local && !p->pack_local)
824 return 0;
825 }
826 }
828 if (nr_objects >= nr_alloc) {
829 nr_alloc = (nr_alloc + 1024) * 3 / 2;
830 objects = xrealloc(objects, nr_alloc * sizeof(*entry));
831 }
833 entry = objects + nr_objects++;
834 memset(entry, 0, sizeof(*entry));
835 hashcpy(entry->idx.sha1, sha1);
836 entry->hash = hash;
837 if (type)
838 entry->type = type;
839 if (exclude)
840 entry->preferred_base = 1;
841 else
842 nr_result++;
843 if (found_pack) {
844 entry->in_pack = found_pack;
845 entry->in_pack_offset = found_offset;
846 }
848 if (object_ix_hashsz * 3 <= nr_objects * 4)
849 rehash_objects();
850 else
851 object_ix[-1 - ix] = nr_objects;
853 if (progress)
854 display_progress(&progress_state, nr_objects);
856 if (name && no_try_delta(name))
857 entry->no_try_delta = 1;
859 return 1;
860 }
862 struct pbase_tree_cache {
863 unsigned char sha1[20];
864 int ref;
865 int temporary;
866 void *tree_data;
867 unsigned long tree_size;
868 };
870 static struct pbase_tree_cache *(pbase_tree_cache[256]);
871 static int pbase_tree_cache_ix(const unsigned char *sha1)
872 {
873 return sha1[0] % ARRAY_SIZE(pbase_tree_cache);
874 }
875 static int pbase_tree_cache_ix_incr(int ix)
876 {
877 return (ix+1) % ARRAY_SIZE(pbase_tree_cache);
878 }
880 static struct pbase_tree {
881 struct pbase_tree *next;
882 /* This is a phony "cache" entry; we are not
883 * going to evict it nor find it through _get()
884 * mechanism -- this is for the toplevel node that
885 * would almost always change with any commit.
886 */
887 struct pbase_tree_cache pcache;
888 } *pbase_tree;
890 static struct pbase_tree_cache *pbase_tree_get(const unsigned char *sha1)
891 {
892 struct pbase_tree_cache *ent, *nent;
893 void *data;
894 unsigned long size;
895 enum object_type type;
896 int neigh;
897 int my_ix = pbase_tree_cache_ix(sha1);
898 int available_ix = -1;
900 /* pbase-tree-cache acts as a limited hashtable.
901 * your object will be found at your index or within a few
902 * slots after that slot if it is cached.
903 */
904 for (neigh = 0; neigh < 8; neigh++) {
905 ent = pbase_tree_cache[my_ix];
906 if (ent && !hashcmp(ent->sha1, sha1)) {
907 ent->ref++;
908 return ent;
909 }
910 else if (((available_ix < 0) && (!ent || !ent->ref)) ||
911 ((0 <= available_ix) &&
912 (!ent && pbase_tree_cache[available_ix])))
913 available_ix = my_ix;
914 if (!ent)
915 break;
916 my_ix = pbase_tree_cache_ix_incr(my_ix);
917 }
919 /* Did not find one. Either we got a bogus request or
920 * we need to read and perhaps cache.
921 */
922 data = read_sha1_file(sha1, &type, &size);
923 if (!data)
924 return NULL;
925 if (type != OBJ_TREE) {
926 free(data);
927 return NULL;
928 }
930 /* We need to either cache or return a throwaway copy */
932 if (available_ix < 0)
933 ent = NULL;
934 else {
935 ent = pbase_tree_cache[available_ix];
936 my_ix = available_ix;
937 }
939 if (!ent) {
940 nent = xmalloc(sizeof(*nent));
941 nent->temporary = (available_ix < 0);
942 }
943 else {
944 /* evict and reuse */
945 free(ent->tree_data);
946 nent = ent;
947 }
948 hashcpy(nent->sha1, sha1);
949 nent->tree_data = data;
950 nent->tree_size = size;
951 nent->ref = 1;
952 if (!nent->temporary)
953 pbase_tree_cache[my_ix] = nent;
954 return nent;
955 }
957 static void pbase_tree_put(struct pbase_tree_cache *cache)
958 {
959 if (!cache->temporary) {
960 cache->ref--;
961 return;
962 }
963 free(cache->tree_data);
964 free(cache);
965 }
967 static int name_cmp_len(const char *name)
968 {
969 int i;
970 for (i = 0; name[i] && name[i] != '\n' && name[i] != '/'; i++)
971 ;
972 return i;
973 }
975 static void add_pbase_object(struct tree_desc *tree,
976 const char *name,
977 int cmplen,
978 const char *fullname)
979 {
980 struct name_entry entry;
981 int cmp;
983 while (tree_entry(tree,&entry)) {
984 cmp = tree_entry_len(entry.path, entry.sha1) != cmplen ? 1 :
985 memcmp(name, entry.path, cmplen);
986 if (cmp > 0)
987 continue;
988 if (cmp < 0)
989 return;
990 if (name[cmplen] != '/') {
991 add_object_entry(entry.sha1,
992 S_ISDIR(entry.mode) ? OBJ_TREE : OBJ_BLOB,
993 fullname, 1);
994 return;
995 }
996 if (S_ISDIR(entry.mode)) {
997 struct tree_desc sub;
998 struct pbase_tree_cache *tree;
999 const char *down = name+cmplen+1;
1000 int downlen = name_cmp_len(down);
1002 tree = pbase_tree_get(entry.sha1);
1003 if (!tree)
1004 return;
1005 init_tree_desc(&sub, tree->tree_data, tree->tree_size);
1007 add_pbase_object(&sub, down, downlen, fullname);
1008 pbase_tree_put(tree);
1009 }
1010 }
1011 }
1013 static unsigned *done_pbase_paths;
1014 static int done_pbase_paths_num;
1015 static int done_pbase_paths_alloc;
1016 static int done_pbase_path_pos(unsigned hash)
1017 {
1018 int lo = 0;
1019 int hi = done_pbase_paths_num;
1020 while (lo < hi) {
1021 int mi = (hi + lo) / 2;
1022 if (done_pbase_paths[mi] == hash)
1023 return mi;
1024 if (done_pbase_paths[mi] < hash)
1025 hi = mi;
1026 else
1027 lo = mi + 1;
1028 }
1029 return -lo-1;
1030 }
1032 static int check_pbase_path(unsigned hash)
1033 {
1034 int pos = (!done_pbase_paths) ? -1 : done_pbase_path_pos(hash);
1035 if (0 <= pos)
1036 return 1;
1037 pos = -pos - 1;
1038 if (done_pbase_paths_alloc <= done_pbase_paths_num) {
1039 done_pbase_paths_alloc = alloc_nr(done_pbase_paths_alloc);
1040 done_pbase_paths = xrealloc(done_pbase_paths,
1041 done_pbase_paths_alloc *
1042 sizeof(unsigned));
1043 }
1044 done_pbase_paths_num++;
1045 if (pos < done_pbase_paths_num)
1046 memmove(done_pbase_paths + pos + 1,
1047 done_pbase_paths + pos,
1048 (done_pbase_paths_num - pos - 1) * sizeof(unsigned));
1049 done_pbase_paths[pos] = hash;
1050 return 0;
1051 }
1053 static void add_preferred_base_object(const char *name)
1054 {
1055 struct pbase_tree *it;
1056 int cmplen;
1057 unsigned hash = name_hash(name);
1059 if (!num_preferred_base || check_pbase_path(hash))
1060 return;
1062 cmplen = name_cmp_len(name);
1063 for (it = pbase_tree; it; it = it->next) {
1064 if (cmplen == 0) {
1065 add_object_entry(it->pcache.sha1, OBJ_TREE, NULL, 1);
1066 }
1067 else {
1068 struct tree_desc tree;
1069 init_tree_desc(&tree, it->pcache.tree_data, it->pcache.tree_size);
1070 add_pbase_object(&tree, name, cmplen, name);
1071 }
1072 }
1073 }
1075 static void add_preferred_base(unsigned char *sha1)
1076 {
1077 struct pbase_tree *it;
1078 void *data;
1079 unsigned long size;
1080 unsigned char tree_sha1[20];
1082 if (window <= num_preferred_base++)
1083 return;
1085 data = read_object_with_reference(sha1, tree_type, &size, tree_sha1);
1086 if (!data)
1087 return;
1089 for (it = pbase_tree; it; it = it->next) {
1090 if (!hashcmp(it->pcache.sha1, tree_sha1)) {
1091 free(data);
1092 return;
1093 }
1094 }
1096 it = xcalloc(1, sizeof(*it));
1097 it->next = pbase_tree;
1098 pbase_tree = it;
1100 hashcpy(it->pcache.sha1, tree_sha1);
1101 it->pcache.tree_data = data;
1102 it->pcache.tree_size = size;
1103 }
1105 static void check_object(struct object_entry *entry)
1106 {
1107 if (entry->in_pack) {
1108 struct packed_git *p = entry->in_pack;
1109 struct pack_window *w_curs = NULL;
1110 const unsigned char *base_ref = NULL;
1111 struct object_entry *base_entry;
1112 unsigned long used, used_0;
1113 unsigned int avail;
1114 off_t ofs;
1115 unsigned char *buf, c;
1117 buf = use_pack(p, &w_curs, entry->in_pack_offset, &avail);
1119 /*
1120 * We want in_pack_type even if we do not reuse delta
1121 * since non-delta representations could still be reused.
1122 */
1123 used = unpack_object_header_gently(buf, avail,
1124 &entry->in_pack_type,
1125 &entry->size);
1127 /*
1128 * Determine if this is a delta and if so whether we can
1129 * reuse it or not. Otherwise let's find out as cheaply as
1130 * possible what the actual type and size for this object is.
1131 */
1132 switch (entry->in_pack_type) {
1133 default:
1134 /* Not a delta hence we've already got all we need. */
1135 entry->type = entry->in_pack_type;
1136 entry->in_pack_header_size = used;
1137 unuse_pack(&w_curs);
1138 return;
1139 case OBJ_REF_DELTA:
1140 if (!no_reuse_delta && !entry->preferred_base)
1141 base_ref = use_pack(p, &w_curs,
1142 entry->in_pack_offset + used, NULL);
1143 entry->in_pack_header_size = used + 20;
1144 break;
1145 case OBJ_OFS_DELTA:
1146 buf = use_pack(p, &w_curs,
1147 entry->in_pack_offset + used, NULL);
1148 used_0 = 0;
1149 c = buf[used_0++];
1150 ofs = c & 127;
1151 while (c & 128) {
1152 ofs += 1;
1153 if (!ofs || MSB(ofs, 7))
1154 die("delta base offset overflow in pack for %s",
1155 sha1_to_hex(entry->idx.sha1));
1156 c = buf[used_0++];
1157 ofs = (ofs << 7) + (c & 127);
1158 }
1159 if (ofs >= entry->in_pack_offset)
1160 die("delta base offset out of bound for %s",
1161 sha1_to_hex(entry->idx.sha1));
1162 ofs = entry->in_pack_offset - ofs;
1163 if (!no_reuse_delta && !entry->preferred_base)
1164 base_ref = find_packed_object_name(p, ofs);
1165 entry->in_pack_header_size = used + used_0;
1166 break;
1167 }
1169 if (base_ref && (base_entry = locate_object_entry(base_ref))) {
1170 /*
1171 * If base_ref was set above that means we wish to
1172 * reuse delta data, and we even found that base
1173 * in the list of objects we want to pack. Goodie!
1174 *
1175 * Depth value does not matter - find_deltas() will
1176 * never consider reused delta as the base object to
1177 * deltify other objects against, in order to avoid
1178 * circular deltas.
1179 */
1180 entry->type = entry->in_pack_type;
1181 entry->delta = base_entry;
1182 entry->delta_sibling = base_entry->delta_child;
1183 base_entry->delta_child = entry;
1184 unuse_pack(&w_curs);
1185 return;
1186 }
1188 if (entry->type) {
1189 /*
1190 * This must be a delta and we already know what the
1191 * final object type is. Let's extract the actual
1192 * object size from the delta header.
1193 */
1194 entry->size = get_size_from_delta(p, &w_curs,
1195 entry->in_pack_offset + entry->in_pack_header_size);
1196 unuse_pack(&w_curs);
1197 return;
1198 }
1200 /*
1201 * No choice but to fall back to the recursive delta walk
1202 * with sha1_object_info() to find about the object type
1203 * at this point...
1204 */
1205 unuse_pack(&w_curs);
1206 }
1208 entry->type = sha1_object_info(entry->idx.sha1, &entry->size);
1209 if (entry->type < 0)
1210 die("unable to get type of object %s",
1211 sha1_to_hex(entry->idx.sha1));
1212 }
1214 static int pack_offset_sort(const void *_a, const void *_b)
1215 {
1216 const struct object_entry *a = *(struct object_entry **)_a;
1217 const struct object_entry *b = *(struct object_entry **)_b;
1219 /* avoid filesystem trashing with loose objects */
1220 if (!a->in_pack && !b->in_pack)
1221 return hashcmp(a->idx.sha1, b->idx.sha1);
1223 if (a->in_pack < b->in_pack)
1224 return -1;
1225 if (a->in_pack > b->in_pack)
1226 return 1;
1227 return a->in_pack_offset < b->in_pack_offset ? -1 :
1228 (a->in_pack_offset > b->in_pack_offset);
1229 }
1231 static void get_object_details(void)
1232 {
1233 uint32_t i;
1234 struct object_entry **sorted_by_offset;
1236 sorted_by_offset = xcalloc(nr_objects, sizeof(struct object_entry *));
1237 for (i = 0; i < nr_objects; i++)
1238 sorted_by_offset[i] = objects + i;
1239 qsort(sorted_by_offset, nr_objects, sizeof(*sorted_by_offset), pack_offset_sort);
1241 prepare_pack_ix();
1242 for (i = 0; i < nr_objects; i++)
1243 check_object(sorted_by_offset[i]);
1244 free(sorted_by_offset);
1245 }
1247 static int type_size_sort(const void *_a, const void *_b)
1248 {
1249 const struct object_entry *a = *(struct object_entry **)_a;
1250 const struct object_entry *b = *(struct object_entry **)_b;
1252 if (a->type < b->type)
1253 return -1;
1254 if (a->type > b->type)
1255 return 1;
1256 if (a->hash < b->hash)
1257 return -1;
1258 if (a->hash > b->hash)
1259 return 1;
1260 if (a->preferred_base < b->preferred_base)
1261 return -1;
1262 if (a->preferred_base > b->preferred_base)
1263 return 1;
1264 if (a->size < b->size)
1265 return -1;
1266 if (a->size > b->size)
1267 return 1;
1268 return a > b ? -1 : (a < b); /* newest last */
1269 }
1271 struct unpacked {
1272 struct object_entry *entry;
1273 void *data;
1274 struct delta_index *index;
1275 unsigned depth;
1276 };
1278 static int delta_cacheable(struct unpacked *trg, struct unpacked *src,
1279 unsigned long src_size, unsigned long trg_size,
1280 unsigned long delta_size)
1281 {
1282 if (max_delta_cache_size && delta_cache_size + delta_size > max_delta_cache_size)
1283 return 0;
1285 if (delta_size < cache_max_small_delta_size)
1286 return 1;
1288 /* cache delta, if objects are large enough compared to delta size */
1289 if ((src_size >> 20) + (trg_size >> 21) > (delta_size >> 10))
1290 return 1;
1292 return 0;
1293 }
1295 /*
1296 * We search for deltas _backwards_ in a list sorted by type and
1297 * by size, so that we see progressively smaller and smaller files.
1298 * That's because we prefer deltas to be from the bigger file
1299 * to the smaller - deletes are potentially cheaper, but perhaps
1300 * more importantly, the bigger file is likely the more recent
1301 * one.
1302 */
1303 static int try_delta(struct unpacked *trg, struct unpacked *src,
1304 unsigned max_depth)
1305 {
1306 struct object_entry *trg_entry = trg->entry;
1307 struct object_entry *src_entry = src->entry;
1308 unsigned long trg_size, src_size, delta_size, sizediff, max_size, sz;
1309 unsigned ref_depth;
1310 enum object_type type;
1311 void *delta_buf;
1313 /* Don't bother doing diffs between different types */
1314 if (trg_entry->type != src_entry->type)
1315 return -1;
1317 /* We do not compute delta to *create* objects we are not
1318 * going to pack.
1319 */
1320 if (trg_entry->preferred_base)
1321 return -1;
1323 /*
1324 * We do not bother to try a delta that we discarded
1325 * on an earlier try, but only when reusing delta data.
1326 */
1327 if (!no_reuse_delta && trg_entry->in_pack &&
1328 trg_entry->in_pack == src_entry->in_pack &&
1329 trg_entry->in_pack_type != OBJ_REF_DELTA &&
1330 trg_entry->in_pack_type != OBJ_OFS_DELTA)
1331 return 0;
1333 /* Let's not bust the allowed depth. */
1334 if (src->depth >= max_depth)
1335 return 0;
1337 /* Now some size filtering heuristics. */
1338 trg_size = trg_entry->size;
1339 if (!trg_entry->delta) {
1340 max_size = trg_size/2 - 20;
1341 ref_depth = 1;
1342 } else {
1343 max_size = trg_entry->delta_size;
1344 ref_depth = trg->depth;
1345 }
1346 max_size = max_size * (max_depth - src->depth) /
1347 (max_depth - ref_depth + 1);
1348 if (max_size == 0)
1349 return 0;
1350 src_size = src_entry->size;
1351 sizediff = src_size < trg_size ? trg_size - src_size : 0;
1352 if (sizediff >= max_size)
1353 return 0;
1354 if (trg_size < src_size / 32)
1355 return 0;
1357 /* Load data if not already done */
1358 if (!trg->data) {
1359 trg->data = read_sha1_file(trg_entry->idx.sha1, &type, &sz);
1360 if (sz != trg_size)
1361 die("object %s inconsistent object length (%lu vs %lu)",
1362 sha1_to_hex(trg_entry->idx.sha1), sz, trg_size);
1363 window_memory_usage += sz;
1364 }
1365 if (!src->data) {
1366 src->data = read_sha1_file(src_entry->idx.sha1, &type, &sz);
1367 if (sz != src_size)
1368 die("object %s inconsistent object length (%lu vs %lu)",
1369 sha1_to_hex(src_entry->idx.sha1), sz, src_size);
1370 window_memory_usage += sz;
1371 }
1372 if (!src->index) {
1373 src->index = create_delta_index(src->data, src_size);
1374 if (!src->index) {
1375 static int warned = 0;
1376 if (!warned++)
1377 warning("suboptimal pack - out of memory");
1378 return 0;
1379 }
1380 window_memory_usage += sizeof_delta_index(src->index);
1381 }
1383 delta_buf = create_delta(src->index, trg->data, trg_size, &delta_size, max_size);
1384 if (!delta_buf)
1385 return 0;
1387 if (trg_entry->delta_data) {
1388 /* Prefer only shallower same-sized deltas. */
1389 if (delta_size == trg_entry->delta_size &&
1390 src->depth + 1 >= trg->depth) {
1391 free(delta_buf);
1392 return 0;
1393 }
1394 delta_cache_size -= trg_entry->delta_size;
1395 free(trg_entry->delta_data);
1396 trg_entry->delta_data = NULL;
1397 }
1398 trg_entry->delta = src_entry;
1399 trg_entry->delta_size = delta_size;
1400 trg->depth = src->depth + 1;
1402 if (delta_cacheable(src, trg, src_size, trg_size, delta_size)) {
1403 trg_entry->delta_data = xrealloc(delta_buf, delta_size);
1404 delta_cache_size += trg_entry->delta_size;
1405 } else
1406 free(delta_buf);
1407 return 1;
1408 }
1410 static unsigned int check_delta_limit(struct object_entry *me, unsigned int n)
1411 {
1412 struct object_entry *child = me->delta_child;
1413 unsigned int m = n;
1414 while (child) {
1415 unsigned int c = check_delta_limit(child, n + 1);
1416 if (m < c)
1417 m = c;
1418 child = child->delta_sibling;
1419 }
1420 return m;
1421 }
1423 static void free_unpacked(struct unpacked *n)
1424 {
1425 window_memory_usage -= sizeof_delta_index(n->index);
1426 free_delta_index(n->index);
1427 n->index = NULL;
1428 if (n->data) {
1429 free(n->data);
1430 n->data = NULL;
1431 window_memory_usage -= n->entry->size;
1432 }
1433 n->entry = NULL;
1434 n->depth = 0;
1435 }
1437 static void find_deltas(struct object_entry **list, int window, int depth)
1438 {
1439 uint32_t i = nr_objects, idx = 0, count = 0, processed = 0;
1440 unsigned int array_size = window * sizeof(struct unpacked);
1441 struct unpacked *array;
1442 int max_depth;
1444 if (!nr_objects)
1445 return;
1446 array = xmalloc(array_size);
1447 memset(array, 0, array_size);
1448 if (progress)
1449 start_progress(&progress_state, "Deltifying %u objects...", "", nr_result);
1451 do {
1452 struct object_entry *entry = list[--i];
1453 struct unpacked *n = array + idx;
1454 int j;
1456 if (!entry->preferred_base)
1457 processed++;
1459 if (progress)
1460 display_progress(&progress_state, processed);
1462 if (entry->delta)
1463 /* This happens if we decided to reuse existing
1464 * delta from a pack. "!no_reuse_delta &&" is implied.
1465 */
1466 continue;
1468 if (entry->size < 50)
1469 continue;
1471 if (entry->no_try_delta)
1472 continue;
1474 free_unpacked(n);
1475 n->entry = entry;
1477 while (window_memory_limit &&
1478 window_memory_usage > window_memory_limit &&
1479 count > 1) {
1480 uint32_t tail = (idx + window - count) % window;
1481 free_unpacked(array + tail);
1482 count--;
1483 }
1485 /*
1486 * If the current object is at pack edge, take the depth the
1487 * objects that depend on the current object into account
1488 * otherwise they would become too deep.
1489 */
1490 max_depth = depth;
1491 if (entry->delta_child) {
1492 max_depth -= check_delta_limit(entry, 0);
1493 if (max_depth <= 0)
1494 goto next;
1495 }
1497 j = window;
1498 while (--j > 0) {
1499 uint32_t other_idx = idx + j;
1500 struct unpacked *m;
1501 if (other_idx >= window)
1502 other_idx -= window;
1503 m = array + other_idx;
1504 if (!m->entry)
1505 break;
1506 if (try_delta(n, m, max_depth) < 0)
1507 break;
1508 }
1510 /* if we made n a delta, and if n is already at max
1511 * depth, leaving it in the window is pointless. we
1512 * should evict it first.
1513 */
1514 if (entry->delta && depth <= n->depth)
1515 continue;
1517 next:
1518 idx++;
1519 if (count + 1 < window)
1520 count++;
1521 if (idx >= window)
1522 idx = 0;
1523 } while (i > 0);
1525 if (progress)
1526 stop_progress(&progress_state);
1528 for (i = 0; i < window; ++i) {
1529 free_delta_index(array[i].index);
1530 free(array[i].data);
1531 }
1532 free(array);
1533 }
1535 static void prepare_pack(int window, int depth)
1536 {
1537 struct object_entry **delta_list;
1538 uint32_t i;
1540 get_object_details();
1542 if (!window || !depth)
1543 return;
1545 delta_list = xmalloc(nr_objects * sizeof(*delta_list));
1546 for (i = 0; i < nr_objects; i++)
1547 delta_list[i] = objects + i;
1548 qsort(delta_list, nr_objects, sizeof(*delta_list), type_size_sort);
1549 find_deltas(delta_list, window+1, depth);
1550 free(delta_list);
1551 }
1553 static int git_pack_config(const char *k, const char *v)
1554 {
1555 if(!strcmp(k, "pack.window")) {
1556 window = git_config_int(k, v);
1557 return 0;
1558 }
1559 if (!strcmp(k, "pack.windowmemory")) {
1560 window_memory_limit = git_config_ulong(k, v);
1561 return 0;
1562 }
1563 if (!strcmp(k, "pack.depth")) {
1564 depth = git_config_int(k, v);
1565 return 0;
1566 }
1567 if (!strcmp(k, "pack.compression")) {
1568 int level = git_config_int(k, v);
1569 if (level == -1)
1570 level = Z_DEFAULT_COMPRESSION;
1571 else if (level < 0 || level > Z_BEST_COMPRESSION)
1572 die("bad pack compression level %d", level);
1573 pack_compression_level = level;
1574 pack_compression_seen = 1;
1575 return 0;
1576 }
1577 if (!strcmp(k, "pack.deltacachesize")) {
1578 max_delta_cache_size = git_config_int(k, v);
1579 return 0;
1580 }
1581 if (!strcmp(k, "pack.deltacachelimit")) {
1582 cache_max_small_delta_size = git_config_int(k, v);
1583 return 0;
1584 }
1585 return git_default_config(k, v);
1586 }
1588 static void read_object_list_from_stdin(void)
1589 {
1590 char line[40 + 1 + PATH_MAX + 2];
1591 unsigned char sha1[20];
1593 for (;;) {
1594 if (!fgets(line, sizeof(line), stdin)) {
1595 if (feof(stdin))
1596 break;
1597 if (!ferror(stdin))
1598 die("fgets returned NULL, not EOF, not error!");
1599 if (errno != EINTR)
1600 die("fgets: %s", strerror(errno));
1601 clearerr(stdin);
1602 continue;
1603 }
1604 if (line[0] == '-') {
1605 if (get_sha1_hex(line+1, sha1))
1606 die("expected edge sha1, got garbage:\n %s",
1607 line);
1608 add_preferred_base(sha1);
1609 continue;
1610 }
1611 if (get_sha1_hex(line, sha1))
1612 die("expected sha1, got garbage:\n %s", line);
1614 add_preferred_base_object(line+41);
1615 add_object_entry(sha1, 0, line+41, 0);
1616 }
1617 }
1619 static void show_commit(struct commit *commit)
1620 {
1621 add_object_entry(commit->object.sha1, OBJ_COMMIT, NULL, 0);
1622 }
1624 static void show_object(struct object_array_entry *p)
1625 {
1626 add_preferred_base_object(p->name);
1627 add_object_entry(p->item->sha1, p->item->type, p->name, 0);
1628 }
1630 static void show_edge(struct commit *commit)
1631 {
1632 add_preferred_base(commit->object.sha1);
1633 }
1635 static void get_object_list(int ac, const char **av)
1636 {
1637 struct rev_info revs;
1638 char line[1000];
1639 int flags = 0;
1641 init_revisions(&revs, NULL);
1642 save_commit_buffer = 0;
1643 track_object_refs = 0;
1644 setup_revisions(ac, av, &revs, NULL);
1646 while (fgets(line, sizeof(line), stdin) != NULL) {
1647 int len = strlen(line);
1648 if (line[len - 1] == '\n')
1649 line[--len] = 0;
1650 if (!len)
1651 break;
1652 if (*line == '-') {
1653 if (!strcmp(line, "--not")) {
1654 flags ^= UNINTERESTING;
1655 continue;
1656 }
1657 die("not a rev '%s'", line);
1658 }
1659 if (handle_revision_arg(line, &revs, flags, 1))
1660 die("bad revision '%s'", line);
1661 }
1663 prepare_revision_walk(&revs);
1664 mark_edges_uninteresting(revs.commits, &revs, show_edge);
1665 traverse_commit_list(&revs, show_commit, show_object);
1666 }
1668 static int adjust_perm(const char *path, mode_t mode)
1669 {
1670 if (chmod(path, mode))
1671 return -1;
1672 return adjust_shared_perm(path);
1673 }
1675 int cmd_pack_objects(int argc, const char **argv, const char *prefix)
1676 {
1677 int use_internal_rev_list = 0;
1678 int thin = 0;
1679 uint32_t i;
1680 const char **rp_av;
1681 int rp_ac_alloc = 64;
1682 int rp_ac;
1684 rp_av = xcalloc(rp_ac_alloc, sizeof(*rp_av));
1686 rp_av[0] = "pack-objects";
1687 rp_av[1] = "--objects"; /* --thin will make it --objects-edge */
1688 rp_ac = 2;
1690 git_config(git_pack_config);
1691 if (!pack_compression_seen && core_compression_seen)
1692 pack_compression_level = core_compression_level;
1694 progress = isatty(2);
1695 for (i = 1; i < argc; i++) {
1696 const char *arg = argv[i];
1698 if (*arg != '-')
1699 break;
1701 if (!strcmp("--non-empty", arg)) {
1702 non_empty = 1;
1703 continue;
1704 }
1705 if (!strcmp("--local", arg)) {
1706 local = 1;
1707 continue;
1708 }
1709 if (!strcmp("--incremental", arg)) {
1710 incremental = 1;
1711 continue;
1712 }
1713 if (!prefixcmp(arg, "--compression=")) {
1714 char *end;
1715 int level = strtoul(arg+14, &end, 0);
1716 if (!arg[14] || *end)
1717 usage(pack_usage);
1718 if (level == -1)
1719 level = Z_DEFAULT_COMPRESSION;
1720 else if (level < 0 || level > Z_BEST_COMPRESSION)
1721 die("bad pack compression level %d", level);
1722 pack_compression_level = level;
1723 continue;
1724 }
1725 if (!prefixcmp(arg, "--max-pack-size=")) {
1726 char *end;
1727 pack_size_limit = strtoul(arg+16, &end, 0) * 1024 * 1024;
1728 if (!arg[16] || *end)
1729 usage(pack_usage);
1730 continue;
1731 }
1732 if (!prefixcmp(arg, "--window=")) {
1733 char *end;
1734 window = strtoul(arg+9, &end, 0);
1735 if (!arg[9] || *end)
1736 usage(pack_usage);
1737 continue;
1738 }
1739 if (!prefixcmp(arg, "--window-memory=")) {
1740 if (!git_parse_ulong(arg+16, &window_memory_limit))
1741 usage(pack_usage);
1742 continue;
1743 }
1744 if (!prefixcmp(arg, "--depth=")) {
1745 char *end;
1746 depth = strtoul(arg+8, &end, 0);
1747 if (!arg[8] || *end)
1748 usage(pack_usage);
1749 continue;
1750 }
1751 if (!strcmp("--progress", arg)) {
1752 progress = 1;
1753 continue;
1754 }
1755 if (!strcmp("--all-progress", arg)) {
1756 progress = 2;
1757 continue;
1758 }
1759 if (!strcmp("-q", arg)) {
1760 progress = 0;
1761 continue;
1762 }
1763 if (!strcmp("--no-reuse-delta", arg)) {
1764 no_reuse_delta = 1;
1765 continue;
1766 }
1767 if (!strcmp("--no-reuse-object", arg)) {
1768 no_reuse_object = no_reuse_delta = 1;
1769 continue;
1770 }
1771 if (!strcmp("--delta-base-offset", arg)) {
1772 allow_ofs_delta = 1;
1773 continue;
1774 }
1775 if (!strcmp("--stdout", arg)) {
1776 pack_to_stdout = 1;
1777 continue;
1778 }
1779 if (!strcmp("--revs", arg)) {
1780 use_internal_rev_list = 1;
1781 continue;
1782 }
1783 if (!strcmp("--unpacked", arg) ||
1784 !prefixcmp(arg, "--unpacked=") ||
1785 !strcmp("--reflog", arg) ||
1786 !strcmp("--all", arg)) {
1787 use_internal_rev_list = 1;
1788 if (rp_ac >= rp_ac_alloc - 1) {
1789 rp_ac_alloc = alloc_nr(rp_ac_alloc);
1790 rp_av = xrealloc(rp_av,
1791 rp_ac_alloc * sizeof(*rp_av));
1792 }
1793 rp_av[rp_ac++] = arg;
1794 continue;
1795 }
1796 if (!strcmp("--thin", arg)) {
1797 use_internal_rev_list = 1;
1798 thin = 1;
1799 rp_av[1] = "--objects-edge";
1800 continue;
1801 }
1802 if (!prefixcmp(arg, "--index-version=")) {
1803 char *c;
1804 pack_idx_default_version = strtoul(arg + 16, &c, 10);
1805 if (pack_idx_default_version > 2)
1806 die("bad %s", arg);
1807 if (*c == ',')
1808 pack_idx_off32_limit = strtoul(c+1, &c, 0);
1809 if (*c || pack_idx_off32_limit & 0x80000000)
1810 die("bad %s", arg);
1811 continue;
1812 }
1813 usage(pack_usage);
1814 }
1816 /* Traditionally "pack-objects [options] base extra" failed;
1817 * we would however want to take refs parameter that would
1818 * have been given to upstream rev-list ourselves, which means
1819 * we somehow want to say what the base name is. So the
1820 * syntax would be:
1821 *
1822 * pack-objects [options] base <refs...>
1823 *
1824 * in other words, we would treat the first non-option as the
1825 * base_name and send everything else to the internal revision
1826 * walker.
1827 */
1829 if (!pack_to_stdout)
1830 base_name = argv[i++];
1832 if (pack_to_stdout != !base_name)
1833 usage(pack_usage);
1835 if (pack_to_stdout && pack_size_limit)
1836 die("--max-pack-size cannot be used to build a pack for transfer.");
1838 if (!pack_to_stdout && thin)
1839 die("--thin cannot be used to build an indexable pack.");
1841 prepare_packed_git();
1843 if (progress)
1844 start_progress(&progress_state, "Generating pack...",
1845 "Counting objects: ", 0);
1846 if (!use_internal_rev_list)
1847 read_object_list_from_stdin();
1848 else {
1849 rp_av[rp_ac] = NULL;
1850 get_object_list(rp_ac, rp_av);
1851 }
1852 if (progress) {
1853 stop_progress(&progress_state);
1854 fprintf(stderr, "Done counting %u objects.\n", nr_objects);
1855 }
1857 if (non_empty && !nr_result)
1858 return 0;
1859 if (progress && (nr_objects != nr_result))
1860 fprintf(stderr, "Result has %u objects.\n", nr_result);
1861 if (nr_result)
1862 prepare_pack(window, depth);
1863 write_pack_file();
1864 if (progress)
1865 fprintf(stderr, "Total %u (delta %u), reused %u (delta %u)\n",
1866 written, written_delta, reused, reused_delta);
1867 return 0;
1868 }