1#include "builtin.h"
2#include "delta.h"
3#include "pack.h"
4#include "csum-file.h"
5#include "blob.h"
6#include "commit.h"
7#include "tag.h"
8#include "tree.h"
9#include "progress.h"
10#include "fsck.h"
11#include "exec_cmd.h"
12static const char index_pack_usage[] =
14"git index-pack [-v] [-o <index-file>] [--keep | --keep=<msg>] [--verify] [--strict] (<pack-file> | --stdin [--fix-thin] [<pack-file>])";
15struct object_entry {
17 struct pack_idx_entry idx;
18 unsigned long size;
19 unsigned int hdr_size;
20 enum object_type type;
21 enum object_type real_type;
22 unsigned delta_depth;
23 int base_object_no;
24};
25union delta_base {
27 unsigned char sha1[20];
28 off_t offset;
29};
30struct base_data {
32 struct base_data *base;
33 struct base_data *child;
34 struct object_entry *obj;
35 void *data;
36 unsigned long size;
37 int ref_first, ref_last;
38 int ofs_first, ofs_last;
39};
40/*
42 * Even if sizeof(union delta_base) == 24 on 64-bit archs, we really want
43 * to memcmp() only the first 20 bytes.
44 */
45#define UNION_BASE_SZ 20
46#define FLAG_LINK (1u<<20)
48#define FLAG_CHECKED (1u<<21)
49struct delta_entry {
51 union delta_base base;
52 int obj_no;
53};
54static struct object_entry *objects;
56static struct delta_entry *deltas;
57static struct base_data *base_cache;
58static size_t base_cache_used;
59static int nr_objects;
60static int nr_deltas;
61static int nr_resolved_deltas;
62static int from_stdin;
64static int strict;
65static int verbose;
66static struct progress *progress;
68/* We always read in 4kB chunks. */
70static unsigned char input_buffer[4096];
71static unsigned int input_offset, input_len;
72static off_t consumed_bytes;
73static unsigned deepest_delta;
74static git_SHA_CTX input_ctx;
75static uint32_t input_crc32;
76static int input_fd, output_fd, pack_fd;
77static int mark_link(struct object *obj, int type, void *data)
79{
80 if (!obj)
81 return -1;
82 if (type != OBJ_ANY && obj->type != type)
84 die(_("object type mismatch at %s"), sha1_to_hex(obj->sha1));
85 obj->flags |= FLAG_LINK;
87 return 0;
88}
89/* The content of each linked object must have been checked
91 or it must be already present in the object database */
92static void check_object(struct object *obj)
93{
94 if (!obj)
95 return;
96 if (!(obj->flags & FLAG_LINK))
98 return;
99 if (!(obj->flags & FLAG_CHECKED)) {
101 unsigned long size;
102 int type = sha1_object_info(obj->sha1, &size);
103 if (type != obj->type || type <= 0)
104 die(_("object of unexpected type"));
105 obj->flags |= FLAG_CHECKED;
106 return;
107 }
108}
109static void check_objects(void)
111{
112 unsigned i, max;
113 max = get_max_object_index();
115 for (i = 0; i < max; i++)
116 check_object(get_indexed_object(i));
117}
118/* Discard current buffer used content. */
121static void flush(void)
122{
123 if (input_offset) {
124 if (output_fd >= 0)
125 write_or_die(output_fd, input_buffer, input_offset);
126 git_SHA1_Update(&input_ctx, input_buffer, input_offset);
127 memmove(input_buffer, input_buffer + input_offset, input_len);
128 input_offset = 0;
129 }
130}
131/*
133 * Make sure at least "min" bytes are available in the buffer, and
134 * return the pointer to the buffer.
135 */
136static void *fill(int min)
137{
138 if (min <= input_len)
139 return input_buffer + input_offset;
140 if (min > sizeof(input_buffer))
141 die(Q_("cannot fill %d byte",
142 "cannot fill %d bytes",
143 min),
144 min);
145 flush();
146 do {
147 ssize_t ret = xread(input_fd, input_buffer + input_len,
148 sizeof(input_buffer) - input_len);
149 if (ret <= 0) {
150 if (!ret)
151 die(_("early EOF"));
152 die_errno(_("read error on input"));
153 }
154 input_len += ret;
155 if (from_stdin)
156 display_throughput(progress, consumed_bytes + input_len);
157 } while (input_len < min);
158 return input_buffer;
159}
160static void use(int bytes)
162{
163 if (bytes > input_len)
164 die(_("used more bytes than were available"));
165 input_crc32 = crc32(input_crc32, input_buffer + input_offset, bytes);
166 input_len -= bytes;
167 input_offset += bytes;
168 /* make sure off_t is sufficiently large not to wrap */
170 if (signed_add_overflows(consumed_bytes, bytes))
171 die(_("pack too large for current definition of off_t"));
172 consumed_bytes += bytes;
173}
174static const char *open_pack_file(const char *pack_name)
176{
177 if (from_stdin) {
178 input_fd = 0;
179 if (!pack_name) {
180 static char tmp_file[PATH_MAX];
181 output_fd = odb_mkstemp(tmp_file, sizeof(tmp_file),
182 "pack/tmp_pack_XXXXXX");
183 pack_name = xstrdup(tmp_file);
184 } else
185 output_fd = open(pack_name, O_CREAT|O_EXCL|O_RDWR, 0600);
186 if (output_fd < 0)
187 die_errno(_("unable to create '%s'"), pack_name);
188 pack_fd = output_fd;
189 } else {
190 input_fd = open(pack_name, O_RDONLY);
191 if (input_fd < 0)
192 die_errno(_("cannot open packfile '%s'"), pack_name);
193 output_fd = -1;
194 pack_fd = input_fd;
195 }
196 git_SHA1_Init(&input_ctx);
197 return pack_name;
198}
199static void parse_pack_header(void)
201{
202 struct pack_header *hdr = fill(sizeof(struct pack_header));
203 /* Header consistency check */
205 if (hdr->hdr_signature != htonl(PACK_SIGNATURE))
206 die(_("pack signature mismatch"));
207 if (!pack_version_ok(hdr->hdr_version))
208 die("pack version %"PRIu32" unsupported",
209 ntohl(hdr->hdr_version));
210 nr_objects = ntohl(hdr->hdr_entries);
212 use(sizeof(struct pack_header));
213}
214static NORETURN void bad_object(unsigned long offset, const char *format,
216 ...) __attribute__((format (printf, 2, 3)));
217static NORETURN void bad_object(unsigned long offset, const char *format, ...)
219{
220 va_list params;
221 char buf[1024];
222 va_start(params, format);
224 vsnprintf(buf, sizeof(buf), format, params);
225 va_end(params);
226 die(_("pack has bad object at offset %lu: %s"), offset, buf);
227}
228static struct base_data *alloc_base_data(void)
230{
231 struct base_data *base = xmalloc(sizeof(struct base_data));
232 memset(base, 0, sizeof(*base));
233 base->ref_last = -1;
234 base->ofs_last = -1;
235 return base;
236}
237static void free_base_data(struct base_data *c)
239{
240 if (c->data) {
241 free(c->data);
242 c->data = NULL;
243 base_cache_used -= c->size;
244 }
245}
246static void prune_base_data(struct base_data *retain)
248{
249 struct base_data *b;
250 for (b = base_cache;
251 base_cache_used > delta_base_cache_limit && b;
252 b = b->child) {
253 if (b->data && b != retain)
254 free_base_data(b);
255 }
256}
257static void link_base_data(struct base_data *base, struct base_data *c)
259{
260 if (base)
261 base->child = c;
262 else
263 base_cache = c;
264 c->base = base;
266 c->child = NULL;
267 if (c->data)
268 base_cache_used += c->size;
269 prune_base_data(c);
270}
271static void unlink_base_data(struct base_data *c)
273{
274 struct base_data *base = c->base;
275 if (base)
276 base->child = NULL;
277 else
278 base_cache = NULL;
279 free_base_data(c);
280}
281static void *unpack_entry_data(unsigned long offset, unsigned long size)
283{
284 int status;
285 git_zstream stream;
286 void *buf = xmalloc(size);
287 memset(&stream, 0, sizeof(stream));
289 git_inflate_init(&stream);
290 stream.next_out = buf;
291 stream.avail_out = size;
292 do {
294 stream.next_in = fill(1);
295 stream.avail_in = input_len;
296 status = git_inflate(&stream, 0);
297 use(input_len - stream.avail_in);
298 } while (status == Z_OK);
299 if (stream.total_out != size || status != Z_STREAM_END)
300 bad_object(offset, _("inflate returned %d"), status);
301 git_inflate_end(&stream);
302 return buf;
303}
304static void *unpack_raw_entry(struct object_entry *obj, union delta_base *delta_base)
306{
307 unsigned char *p;
308 unsigned long size, c;
309 off_t base_offset;
310 unsigned shift;
311 void *data;
312 obj->idx.offset = consumed_bytes;
314 input_crc32 = crc32(0, NULL, 0);
315 p = fill(1);
317 c = *p;
318 use(1);
319 obj->type = (c >> 4) & 7;
320 size = (c & 15);
321 shift = 4;
322 while (c & 0x80) {
323 p = fill(1);
324 c = *p;
325 use(1);
326 size += (c & 0x7f) << shift;
327 shift += 7;
328 }
329 obj->size = size;
330 switch (obj->type) {
332 case OBJ_REF_DELTA:
333 hashcpy(delta_base->sha1, fill(20));
334 use(20);
335 break;
336 case OBJ_OFS_DELTA:
337 memset(delta_base, 0, sizeof(*delta_base));
338 p = fill(1);
339 c = *p;
340 use(1);
341 base_offset = c & 127;
342 while (c & 128) {
343 base_offset += 1;
344 if (!base_offset || MSB(base_offset, 7))
345 bad_object(obj->idx.offset, _("offset value overflow for delta base object"));
346 p = fill(1);
347 c = *p;
348 use(1);
349 base_offset = (base_offset << 7) + (c & 127);
350 }
351 delta_base->offset = obj->idx.offset - base_offset;
352 if (delta_base->offset <= 0 || delta_base->offset >= obj->idx.offset)
353 bad_object(obj->idx.offset, _("delta base offset is out of bound"));
354 break;
355 case OBJ_COMMIT:
356 case OBJ_TREE:
357 case OBJ_BLOB:
358 case OBJ_TAG:
359 break;
360 default:
361 bad_object(obj->idx.offset, _("unknown object type %d"), obj->type);
362 }
363 obj->hdr_size = consumed_bytes - obj->idx.offset;
364 data = unpack_entry_data(obj->idx.offset, obj->size);
366 obj->idx.crc32 = input_crc32;
367 return data;
368}
369static void *get_data_from_pack(struct object_entry *obj)
371{
372 off_t from = obj[0].idx.offset + obj[0].hdr_size;
373 unsigned long len = obj[1].idx.offset - from;
374 unsigned char *data, *inbuf;
375 git_zstream stream;
376 int status;
377 data = xmalloc(obj->size);
379 inbuf = xmalloc((len < 64*1024) ? len : 64*1024);
380 memset(&stream, 0, sizeof(stream));
382 git_inflate_init(&stream);
383 stream.next_out = data;
384 stream.avail_out = obj->size;
385 do {
387 ssize_t n = (len < 64*1024) ? len : 64*1024;
388 n = pread(pack_fd, inbuf, n, from);
389 if (n < 0)
390 die_errno(_("cannot pread pack file"));
391 if (!n)
392 die(Q_("premature end of pack file, %lu byte missing",
393 "premature end of pack file, %lu bytes missing",
394 len),
395 len);
396 from += n;
397 len -= n;
398 stream.next_in = inbuf;
399 stream.avail_in = n;
400 status = git_inflate(&stream, 0);
401 } while (len && status == Z_OK && !stream.avail_in);
402 /* This has been inflated OK when first encountered, so... */
404 if (status != Z_STREAM_END || stream.total_out != obj->size)
405 die(_("serious inflate inconsistency"));
406 git_inflate_end(&stream);
408 free(inbuf);
409 return data;
410}
411static int compare_delta_bases(const union delta_base *base1,
413 const union delta_base *base2,
414 enum object_type type1,
415 enum object_type type2)
416{
417 int cmp = type1 - type2;
418 if (cmp)
419 return cmp;
420 return memcmp(base1, base2, UNION_BASE_SZ);
421}
422static int find_delta(const union delta_base *base, enum object_type type)
424{
425 int first = 0, last = nr_deltas;
426 while (first < last) {
428 int next = (first + last) / 2;
429 struct delta_entry *delta = &deltas[next];
430 int cmp;
431 cmp = compare_delta_bases(base, &delta->base,
433 type, objects[delta->obj_no].type);
434 if (!cmp)
435 return next;
436 if (cmp < 0) {
437 last = next;
438 continue;
439 }
440 first = next+1;
441 }
442 return -first-1;
443}
444static void find_delta_children(const union delta_base *base,
446 int *first_index, int *last_index,
447 enum object_type type)
448{
449 int first = find_delta(base, type);
450 int last = first;
451 int end = nr_deltas - 1;
452 if (first < 0) {
454 *first_index = 0;
455 *last_index = -1;
456 return;
457 }
458 while (first > 0 && !memcmp(&deltas[first - 1].base, base, UNION_BASE_SZ))
459 --first;
460 while (last < end && !memcmp(&deltas[last + 1].base, base, UNION_BASE_SZ))
461 ++last;
462 *first_index = first;
463 *last_index = last;
464}
465static void sha1_object(const void *data, unsigned long size,
467 enum object_type type, unsigned char *sha1)
468{
469 hash_sha1_file(data, size, typename(type), sha1);
470 if (has_sha1_file(sha1)) {
471 void *has_data;
472 enum object_type has_type;
473 unsigned long has_size;
474 has_data = read_sha1_file(sha1, &has_type, &has_size);
475 if (!has_data)
476 die(_("cannot read existing object %s"), sha1_to_hex(sha1));
477 if (size != has_size || type != has_type ||
478 memcmp(data, has_data, size) != 0)
479 die(_("SHA1 COLLISION FOUND WITH %s !"), sha1_to_hex(sha1));
480 free(has_data);
481 }
482 if (strict) {
483 if (type == OBJ_BLOB) {
484 struct blob *blob = lookup_blob(sha1);
485 if (blob)
486 blob->object.flags |= FLAG_CHECKED;
487 else
488 die(_("invalid blob object %s"), sha1_to_hex(sha1));
489 } else {
490 struct object *obj;
491 int eaten;
492 void *buf = (void *) data;
493 /*
495 * we do not need to free the memory here, as the
496 * buf is deleted by the caller.
497 */
498 obj = parse_object_buffer(sha1, type, size, buf, &eaten);
499 if (!obj)
500 die(_("invalid %s"), typename(type));
501 if (fsck_object(obj, 1, fsck_error_function))
502 die(_("Error in object"));
503 if (fsck_walk(obj, mark_link, NULL))
504 die(_("Not all child objects of %s are reachable"), sha1_to_hex(obj->sha1));
505 if (obj->type == OBJ_TREE) {
507 struct tree *item = (struct tree *) obj;
508 item->buffer = NULL;
509 }
510 if (obj->type == OBJ_COMMIT) {
511 struct commit *commit = (struct commit *) obj;
512 commit->buffer = NULL;
513 }
514 obj->flags |= FLAG_CHECKED;
515 }
516 }
517}
518static int is_delta_type(enum object_type type)
520{
521 return (type == OBJ_REF_DELTA || type == OBJ_OFS_DELTA);
522}
523/*
525 * This function is part of find_unresolved_deltas(). There are two
526 * walkers going in the opposite ways.
527 *
528 * The first one in find_unresolved_deltas() traverses down from
529 * parent node to children, deflating nodes along the way. However,
530 * memory for deflated nodes is limited by delta_base_cache_limit, so
531 * at some point parent node's deflated content may be freed.
532 *
533 * The second walker is this function, which goes from current node up
534 * to top parent if necessary to deflate the node. In normal
535 * situation, its parent node would be already deflated, so it just
536 * needs to apply delta.
537 *
538 * In the worst case scenario, parent node is no longer deflated because
539 * we're running out of delta_base_cache_limit; we need to re-deflate
540 * parents, possibly up to the top base.
541 *
542 * All deflated objects here are subject to be freed if we exceed
543 * delta_base_cache_limit, just like in find_unresolved_deltas(), we
544 * just need to make sure the last node is not freed.
545 */
546static void *get_base_data(struct base_data *c)
547{
548 if (!c->data) {
549 struct object_entry *obj = c->obj;
550 struct base_data **delta = NULL;
551 int delta_nr = 0, delta_alloc = 0;
552 while (is_delta_type(c->obj->type) && !c->data) {
554 ALLOC_GROW(delta, delta_nr + 1, delta_alloc);
555 delta[delta_nr++] = c;
556 c = c->base;
557 }
558 if (!delta_nr) {
559 c->data = get_data_from_pack(obj);
560 c->size = obj->size;
561 base_cache_used += c->size;
562 prune_base_data(c);
563 }
564 for (; delta_nr > 0; delta_nr--) {
565 void *base, *raw;
566 c = delta[delta_nr - 1];
567 obj = c->obj;
568 base = get_base_data(c->base);
569 raw = get_data_from_pack(obj);
570 c->data = patch_delta(
571 base, c->base->size,
572 raw, obj->size,
573 &c->size);
574 free(raw);
575 if (!c->data)
576 bad_object(obj->idx.offset, _("failed to apply delta"));
577 base_cache_used += c->size;
578 prune_base_data(c);
579 }
580 free(delta);
581 }
582 return c->data;
583}
584static void resolve_delta(struct object_entry *delta_obj,
586 struct base_data *base, struct base_data *result)
587{
588 void *base_data, *delta_data;
589 delta_obj->real_type = base->obj->real_type;
591 delta_obj->delta_depth = base->obj->delta_depth + 1;
592 if (deepest_delta < delta_obj->delta_depth)
593 deepest_delta = delta_obj->delta_depth;
594 delta_obj->base_object_no = base->obj - objects;
595 delta_data = get_data_from_pack(delta_obj);
596 base_data = get_base_data(base);
597 result->obj = delta_obj;
598 result->data = patch_delta(base_data, base->size,
599 delta_data, delta_obj->size, &result->size);
600 free(delta_data);
601 if (!result->data)
602 bad_object(delta_obj->idx.offset, _("failed to apply delta"));
603 sha1_object(result->data, result->size, delta_obj->real_type,
604 delta_obj->idx.sha1);
605 nr_resolved_deltas++;
606}
607static struct base_data *find_unresolved_deltas_1(struct base_data *base,
609 struct base_data *prev_base)
610{
611 if (base->ref_last == -1 && base->ofs_last == -1) {
612 union delta_base base_spec;
613 hashcpy(base_spec.sha1, base->obj->idx.sha1);
615 find_delta_children(&base_spec,
616 &base->ref_first, &base->ref_last, OBJ_REF_DELTA);
617 memset(&base_spec, 0, sizeof(base_spec));
619 base_spec.offset = base->obj->idx.offset;
620 find_delta_children(&base_spec,
621 &base->ofs_first, &base->ofs_last, OBJ_OFS_DELTA);
622 if (base->ref_last == -1 && base->ofs_last == -1) {
624 free(base->data);
625 return NULL;
626 }
627 link_base_data(prev_base, base);
629 }
630 if (base->ref_first <= base->ref_last) {
632 struct object_entry *child = objects + deltas[base->ref_first].obj_no;
633 struct base_data *result = alloc_base_data();
634 assert(child->real_type == OBJ_REF_DELTA);
636 resolve_delta(child, base, result);
637 if (base->ref_first == base->ref_last && base->ofs_last == -1)
638 free_base_data(base);
639 base->ref_first++;
641 return result;
642 }
643 if (base->ofs_first <= base->ofs_last) {
645 struct object_entry *child = objects + deltas[base->ofs_first].obj_no;
646 struct base_data *result = alloc_base_data();
647 assert(child->real_type == OBJ_OFS_DELTA);
649 resolve_delta(child, base, result);
650 if (base->ofs_first == base->ofs_last)
651 free_base_data(base);
652 base->ofs_first++;
654 return result;
655 }
656 unlink_base_data(base);
658 return NULL;
659}
660static void find_unresolved_deltas(struct base_data *base)
662{
663 struct base_data *new_base, *prev_base = NULL;
664 for (;;) {
665 new_base = find_unresolved_deltas_1(base, prev_base);
666 if (new_base) {
668 prev_base = base;
669 base = new_base;
670 } else {
671 free(base);
672 base = prev_base;
673 if (!base)
674 return;
675 prev_base = base->base;
676 }
677 }
678}
679static int compare_delta_entry(const void *a, const void *b)
681{
682 const struct delta_entry *delta_a = a;
683 const struct delta_entry *delta_b = b;
684 /* group by type (ref vs ofs) and then by value (sha-1 or offset) */
686 return compare_delta_bases(&delta_a->base, &delta_b->base,
687 objects[delta_a->obj_no].type,
688 objects[delta_b->obj_no].type);
689}
690/* Parse all objects and return the pack content SHA1 hash */
692static void parse_pack_objects(unsigned char *sha1)
693{
694 int i;
695 struct delta_entry *delta = deltas;
696 struct stat st;
697 /*
699 * First pass:
700 * - find locations of all objects;
701 * - calculate SHA1 of all non-delta objects;
702 * - remember base (SHA1 or offset) for all deltas.
703 */
704 if (verbose)
705 progress = start_progress(
706 from_stdin ? _("Receiving objects") : _("Indexing objects"),
707 nr_objects);
708 for (i = 0; i < nr_objects; i++) {
709 struct object_entry *obj = &objects[i];
710 void *data = unpack_raw_entry(obj, &delta->base);
711 obj->real_type = obj->type;
712 if (is_delta_type(obj->type)) {
713 nr_deltas++;
714 delta->obj_no = i;
715 delta++;
716 } else
717 sha1_object(data, obj->size, obj->type, obj->idx.sha1);
718 free(data);
719 display_progress(progress, i+1);
720 }
721 objects[i].idx.offset = consumed_bytes;
722 stop_progress(&progress);
723 /* Check pack integrity */
725 flush();
726 git_SHA1_Final(sha1, &input_ctx);
727 if (hashcmp(fill(20), sha1))
728 die(_("pack is corrupted (SHA1 mismatch)"));
729 use(20);
730 /* If input_fd is a file, we should have reached its end now. */
732 if (fstat(input_fd, &st))
733 die_errno(_("cannot fstat packfile"));
734 if (S_ISREG(st.st_mode) &&
735 lseek(input_fd, 0, SEEK_CUR) - input_len != st.st_size)
736 die(_("pack has junk at the end"));
737 if (!nr_deltas)
739 return;
740 /* Sort deltas by base SHA1/offset for fast searching */
742 qsort(deltas, nr_deltas, sizeof(struct delta_entry),
743 compare_delta_entry);
744 /*
746 * Second pass:
747 * - for all non-delta objects, look if it is used as a base for
748 * deltas;
749 * - if used as a base, uncompress the object and apply all deltas,
750 * recursively checking if the resulting object is used as a base
751 * for some more deltas.
752 */
753 if (verbose)
754 progress = start_progress(_("Resolving deltas"), nr_deltas);
755 for (i = 0; i < nr_objects; i++) {
756 struct object_entry *obj = &objects[i];
757 struct base_data *base_obj = alloc_base_data();
758 if (is_delta_type(obj->type))
760 continue;
761 base_obj->obj = obj;
762 base_obj->data = NULL;
763 find_unresolved_deltas(base_obj);
764 display_progress(progress, nr_resolved_deltas);
765 }
766}
767static int write_compressed(struct sha1file *f, void *in, unsigned int size)
769{
770 git_zstream stream;
771 int status;
772 unsigned char outbuf[4096];
773 memset(&stream, 0, sizeof(stream));
775 git_deflate_init(&stream, zlib_compression_level);
776 stream.next_in = in;
777 stream.avail_in = size;
778 do {
780 stream.next_out = outbuf;
781 stream.avail_out = sizeof(outbuf);
782 status = git_deflate(&stream, Z_FINISH);
783 sha1write(f, outbuf, sizeof(outbuf) - stream.avail_out);
784 } while (status == Z_OK);
785 if (status != Z_STREAM_END)
787 die(_("unable to deflate appended object (%d)"), status);
788 size = stream.total_out;
789 git_deflate_end(&stream);
790 return size;
791}
792static struct object_entry *append_obj_to_pack(struct sha1file *f,
794 const unsigned char *sha1, void *buf,
795 unsigned long size, enum object_type type)
796{
797 struct object_entry *obj = &objects[nr_objects++];
798 unsigned char header[10];
799 unsigned long s = size;
800 int n = 0;
801 unsigned char c = (type << 4) | (s & 15);
802 s >>= 4;
803 while (s) {
804 header[n++] = c | 0x80;
805 c = s & 0x7f;
806 s >>= 7;
807 }
808 header[n++] = c;
809 crc32_begin(f);
810 sha1write(f, header, n);
811 obj[0].size = size;
812 obj[0].hdr_size = n;
813 obj[0].type = type;
814 obj[0].real_type = type;
815 obj[1].idx.offset = obj[0].idx.offset + n;
816 obj[1].idx.offset += write_compressed(f, buf, size);
817 obj[0].idx.crc32 = crc32_end(f);
818 sha1flush(f);
819 hashcpy(obj->idx.sha1, sha1);
820 return obj;
821}
822static int delta_pos_compare(const void *_a, const void *_b)
824{
825 struct delta_entry *a = *(struct delta_entry **)_a;
826 struct delta_entry *b = *(struct delta_entry **)_b;
827 return a->obj_no - b->obj_no;
828}
829static void fix_unresolved_deltas(struct sha1file *f, int nr_unresolved)
831{
832 struct delta_entry **sorted_by_pos;
833 int i, n = 0;
834 /*
836 * Since many unresolved deltas may well be themselves base objects
837 * for more unresolved deltas, we really want to include the
838 * smallest number of base objects that would cover as much delta
839 * as possible by picking the
840 * trunc deltas first, allowing for other deltas to resolve without
841 * additional base objects. Since most base objects are to be found
842 * before deltas depending on them, a good heuristic is to start
843 * resolving deltas in the same order as their position in the pack.
844 */
845 sorted_by_pos = xmalloc(nr_unresolved * sizeof(*sorted_by_pos));
846 for (i = 0; i < nr_deltas; i++) {
847 if (objects[deltas[i].obj_no].real_type != OBJ_REF_DELTA)
848 continue;
849 sorted_by_pos[n++] = &deltas[i];
850 }
851 qsort(sorted_by_pos, n, sizeof(*sorted_by_pos), delta_pos_compare);
852 for (i = 0; i < n; i++) {
854 struct delta_entry *d = sorted_by_pos[i];
855 enum object_type type;
856 struct base_data *base_obj = alloc_base_data();
857 if (objects[d->obj_no].real_type != OBJ_REF_DELTA)
859 continue;
860 base_obj->data = read_sha1_file(d->base.sha1, &type, &base_obj->size);
861 if (!base_obj->data)
862 continue;
863 if (check_sha1_signature(d->base.sha1, base_obj->data,
865 base_obj->size, typename(type)))
866 die(_("local object %s is corrupt"), sha1_to_hex(d->base.sha1));
867 base_obj->obj = append_obj_to_pack(f, d->base.sha1,
868 base_obj->data, base_obj->size, type);
869 find_unresolved_deltas(base_obj);
870 display_progress(progress, nr_resolved_deltas);
871 }
872 free(sorted_by_pos);
873}
874static void final(const char *final_pack_name, const char *curr_pack_name,
876 const char *final_index_name, const char *curr_index_name,
877 const char *keep_name, const char *keep_msg,
878 unsigned char *sha1)
879{
880 const char *report = "pack";
881 char name[PATH_MAX];
882 int err;
883 if (!from_stdin) {
885 close(input_fd);
886 } else {
887 fsync_or_die(output_fd, curr_pack_name);
888 err = close(output_fd);
889 if (err)
890 die_errno(_("error while closing pack file"));
891 }
892 if (keep_msg) {
894 int keep_fd, keep_msg_len = strlen(keep_msg);
895 if (!keep_name)
897 keep_fd = odb_pack_keep(name, sizeof(name), sha1);
898 else
899 keep_fd = open(keep_name, O_RDWR|O_CREAT|O_EXCL, 0600);
900 if (keep_fd < 0) {
902 if (errno != EEXIST)
903 die_errno(_("cannot write keep file '%s'"),
904 keep_name);
905 } else {
906 if (keep_msg_len > 0) {
907 write_or_die(keep_fd, keep_msg, keep_msg_len);
908 write_or_die(keep_fd, "\n", 1);
909 }
910 if (close(keep_fd) != 0)
911 die_errno(_("cannot close written keep file '%s'"),
912 keep_name);
913 report = "keep";
914 }
915 }
916 if (final_pack_name != curr_pack_name) {
918 if (!final_pack_name) {
919 snprintf(name, sizeof(name), "%s/pack/pack-%s.pack",
920 get_object_directory(), sha1_to_hex(sha1));
921 final_pack_name = name;
922 }
923 if (move_temp_to_file(curr_pack_name, final_pack_name))
924 die(_("cannot store pack file"));
925 } else if (from_stdin)
926 chmod(final_pack_name, 0444);
927 if (final_index_name != curr_index_name) {
929 if (!final_index_name) {
930 snprintf(name, sizeof(name), "%s/pack/pack-%s.idx",
931 get_object_directory(), sha1_to_hex(sha1));
932 final_index_name = name;
933 }
934 if (move_temp_to_file(curr_index_name, final_index_name))
935 die(_("cannot store index file"));
936 } else
937 chmod(final_index_name, 0444);
938 if (!from_stdin) {
940 printf("%s\n", sha1_to_hex(sha1));
941 } else {
942 char buf[48];
943 int len = snprintf(buf, sizeof(buf), "%s\t%s\n",
944 report, sha1_to_hex(sha1));
945 write_or_die(1, buf, len);
946 /*
948 * Let's just mimic git-unpack-objects here and write
949 * the last part of the input buffer to stdout.
950 */
951 while (input_len) {
952 err = xwrite(1, input_buffer + input_offset, input_len);
953 if (err <= 0)
954 break;
955 input_len -= err;
956 input_offset += err;
957 }
958 }
959}
960static int git_index_pack_config(const char *k, const char *v, void *cb)
962{
963 struct pack_idx_option *opts = cb;
964 if (!strcmp(k, "pack.indexversion")) {
966 opts->version = git_config_int(k, v);
967 if (opts->version > 2)
968 die("bad pack.indexversion=%"PRIu32, opts->version);
969 return 0;
970 }
971 return git_default_config(k, v, cb);
972}
973static int cmp_uint32(const void *a_, const void *b_)
975{
976 uint32_t a = *((uint32_t *)a_);
977 uint32_t b = *((uint32_t *)b_);
978 return (a < b) ? -1 : (a != b);
980}
981static void read_v2_anomalous_offsets(struct packed_git *p,
983 struct pack_idx_option *opts)
984{
985 const uint32_t *idx1, *idx2;
986 uint32_t i;
987 /* The address of the 4-byte offset table */
989 idx1 = (((const uint32_t *)p->index_data)
990 + 2 /* 8-byte header */
991 + 256 /* fan out */
992 + 5 * p->num_objects /* 20-byte SHA-1 table */
993 + p->num_objects /* CRC32 table */
994 );
995 /* The address of the 8-byte offset table */
997 idx2 = idx1 + p->num_objects;
998 for (i = 0; i < p->num_objects; i++) {
1000 uint32_t off = ntohl(idx1[i]);
1001 if (!(off & 0x80000000))
1002 continue;
1003 off = off & 0x7fffffff;
1004 if (idx2[off * 2])
1005 continue;
1006 /*
1007 * The real offset is ntohl(idx2[off * 2]) in high 4
1008 * octets, and ntohl(idx2[off * 2 + 1]) in low 4
1009 * octets. But idx2[off * 2] is Zero!!!
1010 */
1011 ALLOC_GROW(opts->anomaly, opts->anomaly_nr + 1, opts->anomaly_alloc);
1012 opts->anomaly[opts->anomaly_nr++] = ntohl(idx2[off * 2 + 1]);
1013 }
1014 if (1 < opts->anomaly_nr)
1016 qsort(opts->anomaly, opts->anomaly_nr, sizeof(uint32_t), cmp_uint32);
1017}
1018static void read_idx_option(struct pack_idx_option *opts, const char *pack_name)
1020{
1021 struct packed_git *p = add_packed_git(pack_name, strlen(pack_name), 1);
1022 if (!p)
1024 die(_("Cannot open existing pack file '%s'"), pack_name);
1025 if (open_pack_index(p))
1026 die(_("Cannot open existing pack idx file for '%s'"), pack_name);
1027 /* Read the attributes from the existing idx file */
1029 opts->version = p->index_version;
1030 if (opts->version == 2)
1032 read_v2_anomalous_offsets(p, opts);
1033 /*
1035 * Get rid of the idx file as we do not need it anymore.
1036 * NEEDSWORK: extract this bit from free_pack_by_name() in
1037 * sha1_file.c, perhaps? It shouldn't matter very much as we
1038 * know we haven't installed this pack (hence we never have
1039 * read anything from it).
1040 */
1041 close_pack_index(p);
1042 free(p);
1043}
1044static void show_pack_info(int stat_only)
1046{
1047 int i, baseobjects = nr_objects - nr_deltas;
1048 unsigned long *chain_histogram = NULL;
1049 if (deepest_delta)
1051 chain_histogram = xcalloc(deepest_delta, sizeof(unsigned long));
1052 for (i = 0; i < nr_objects; i++) {
1054 struct object_entry *obj = &objects[i];
1055 if (is_delta_type(obj->type))
1057 chain_histogram[obj->delta_depth - 1]++;
1058 if (stat_only)
1059 continue;
1060 printf("%s %-6s %lu %lu %"PRIuMAX,
1061 sha1_to_hex(obj->idx.sha1),
1062 typename(obj->real_type), obj->size,
1063 (unsigned long)(obj[1].idx.offset - obj->idx.offset),
1064 (uintmax_t)obj->idx.offset);
1065 if (is_delta_type(obj->type)) {
1066 struct object_entry *bobj = &objects[obj->base_object_no];
1067 printf(" %u %s", obj->delta_depth, sha1_to_hex(bobj->idx.sha1));
1068 }
1069 putchar('\n');
1070 }
1071 if (baseobjects)
1073 printf_ln(Q_("non delta: %d object",
1074 "non delta: %d objects",
1075 baseobjects),
1076 baseobjects);
1077 for (i = 0; i < deepest_delta; i++) {
1078 if (!chain_histogram[i])
1079 continue;
1080 printf_ln(Q_("chain length = %d: %lu object",
1081 "chain length = %d: %lu objects",
1082 chain_histogram[i]),
1083 i + 1,
1084 chain_histogram[i]);
1085 }
1086}
1087int cmd_index_pack(int argc, const char **argv, const char *prefix)
1089{
1090 int i, fix_thin_pack = 0, verify = 0, stat_only = 0, stat = 0;
1091 const char *curr_pack, *curr_index;
1092 const char *index_name = NULL, *pack_name = NULL;
1093 const char *keep_name = NULL, *keep_msg = NULL;
1094 char *index_name_buf = NULL, *keep_name_buf = NULL;
1095 struct pack_idx_entry **idx_objects;
1096 struct pack_idx_option opts;
1097 unsigned char pack_sha1[20];
1098 if (argc == 2 && !strcmp(argv[1], "-h"))
1100 usage(index_pack_usage);
1101 read_replace_refs = 0;
1103 reset_pack_idx_option(&opts);
1105 git_config(git_index_pack_config, &opts);
1106 if (prefix && chdir(prefix))
1107 die(_("Cannot come back to cwd"));
1108 for (i = 1; i < argc; i++) {
1110 const char *arg = argv[i];
1111 if (*arg == '-') {
1113 if (!strcmp(arg, "--stdin")) {
1114 from_stdin = 1;
1115 } else if (!strcmp(arg, "--fix-thin")) {
1116 fix_thin_pack = 1;
1117 } else if (!strcmp(arg, "--strict")) {
1118 strict = 1;
1119 } else if (!strcmp(arg, "--verify")) {
1120 verify = 1;
1121 } else if (!strcmp(arg, "--verify-stat")) {
1122 verify = 1;
1123 stat = 1;
1124 } else if (!strcmp(arg, "--verify-stat-only")) {
1125 verify = 1;
1126 stat = 1;
1127 stat_only = 1;
1128 } else if (!strcmp(arg, "--keep")) {
1129 keep_msg = "";
1130 } else if (!prefixcmp(arg, "--keep=")) {
1131 keep_msg = arg + 7;
1132 } else if (!prefixcmp(arg, "--pack_header=")) {
1133 struct pack_header *hdr;
1134 char *c;
1135 hdr = (struct pack_header *)input_buffer;
1137 hdr->hdr_signature = htonl(PACK_SIGNATURE);
1138 hdr->hdr_version = htonl(strtoul(arg + 14, &c, 10));
1139 if (*c != ',')
1140 die(_("bad %s"), arg);
1141 hdr->hdr_entries = htonl(strtoul(c + 1, &c, 10));
1142 if (*c)
1143 die(_("bad %s"), arg);
1144 input_len = sizeof(*hdr);
1145 } else if (!strcmp(arg, "-v")) {
1146 verbose = 1;
1147 } else if (!strcmp(arg, "-o")) {
1148 if (index_name || (i+1) >= argc)
1149 usage(index_pack_usage);
1150 index_name = argv[++i];
1151 } else if (!prefixcmp(arg, "--index-version=")) {
1152 char *c;
1153 opts.version = strtoul(arg + 16, &c, 10);
1154 if (opts.version > 2)
1155 die(_("bad %s"), arg);
1156 if (*c == ',')
1157 opts.off32_limit = strtoul(c+1, &c, 0);
1158 if (*c || opts.off32_limit & 0x80000000)
1159 die(_("bad %s"), arg);
1160 } else
1161 usage(index_pack_usage);
1162 continue;
1163 }
1164 if (pack_name)
1166 usage(index_pack_usage);
1167 pack_name = arg;
1168 }
1169 if (!pack_name && !from_stdin)
1171 usage(index_pack_usage);
1172 if (fix_thin_pack && !from_stdin)
1173 die(_("--fix-thin cannot be used without --stdin"));
1174 if (!index_name && pack_name) {
1175 int len = strlen(pack_name);
1176 if (!has_extension(pack_name, ".pack"))
1177 die(_("packfile name '%s' does not end with '.pack'"),
1178 pack_name);
1179 index_name_buf = xmalloc(len);
1180 memcpy(index_name_buf, pack_name, len - 5);
1181 strcpy(index_name_buf + len - 5, ".idx");
1182 index_name = index_name_buf;
1183 }
1184 if (keep_msg && !keep_name && pack_name) {
1185 int len = strlen(pack_name);
1186 if (!has_extension(pack_name, ".pack"))
1187 die(_("packfile name '%s' does not end with '.pack'"),
1188 pack_name);
1189 keep_name_buf = xmalloc(len);
1190 memcpy(keep_name_buf, pack_name, len - 5);
1191 strcpy(keep_name_buf + len - 5, ".keep");
1192 keep_name = keep_name_buf;
1193 }
1194 if (verify) {
1195 if (!index_name)
1196 die(_("--verify with no packfile name given"));
1197 read_idx_option(&opts, index_name);
1198 opts.flags |= WRITE_IDX_VERIFY | WRITE_IDX_STRICT;
1199 }
1200 if (strict)
1201 opts.flags |= WRITE_IDX_STRICT;
1202 curr_pack = open_pack_file(pack_name);
1204 parse_pack_header();
1205 objects = xcalloc(nr_objects + 1, sizeof(struct object_entry));
1206 deltas = xcalloc(nr_objects, sizeof(struct delta_entry));
1207 parse_pack_objects(pack_sha1);
1208 if (nr_deltas == nr_resolved_deltas) {
1209 stop_progress(&progress);
1210 /* Flush remaining pack final 20-byte SHA1. */
1211 flush();
1212 } else {
1213 if (fix_thin_pack) {
1214 struct sha1file *f;
1215 unsigned char read_sha1[20], tail_sha1[20];
1216 char msg[48];
1217 int nr_unresolved = nr_deltas - nr_resolved_deltas;
1218 int nr_objects_initial = nr_objects;
1219 if (nr_unresolved <= 0)
1220 die(_("confusion beyond insanity"));
1221 objects = xrealloc(objects,
1222 (nr_objects + nr_unresolved + 1)
1223 * sizeof(*objects));
1224 f = sha1fd(output_fd, curr_pack);
1225 fix_unresolved_deltas(f, nr_unresolved);
1226 sprintf(msg, "completed with %d local objects",
1227 nr_objects - nr_objects_initial);
1228 stop_progress_msg(&progress, msg);
1229 sha1close(f, tail_sha1, 0);
1230 hashcpy(read_sha1, pack_sha1);
1231 fixup_pack_header_footer(output_fd, pack_sha1,
1232 curr_pack, nr_objects,
1233 read_sha1, consumed_bytes-20);
1234 if (hashcmp(read_sha1, tail_sha1) != 0)
1235 die("Unexpected tail checksum for %s "
1236 "(disk corruption?)", curr_pack);
1237 }
1238 if (nr_deltas != nr_resolved_deltas)
1239 die(Q_("pack has %d unresolved delta",
1240 "pack has %d unresolved deltas",
1241 nr_deltas - nr_resolved_deltas),
1242 nr_deltas - nr_resolved_deltas);
1243 }
1244 free(deltas);
1245 if (strict)
1246 check_objects();
1247 if (stat)
1249 show_pack_info(stat_only);
1250 idx_objects = xmalloc((nr_objects) * sizeof(struct pack_idx_entry *));
1252 for (i = 0; i < nr_objects; i++)
1253 idx_objects[i] = &objects[i].idx;
1254 curr_index = write_idx_file(index_name, idx_objects, nr_objects, &opts, pack_sha1);
1255 free(idx_objects);
1256 if (!verify)
1258 final(pack_name, curr_pack,
1259 index_name, curr_index,
1260 keep_name, keep_msg,
1261 pack_sha1);
1262 else
1263 close(input_fd);
1264 free(objects);
1265 free(index_name_buf);
1266 free(keep_name_buf);
1267 if (pack_name == NULL)
1268 free((void *) curr_pack);
1269 if (index_name == NULL)
1270 free((void *) curr_index);
1271 return 0;
1273}