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};
38/*
40 * Even if sizeof(union delta_base) == 24 on 64-bit archs, we really want
41 * to memcmp() only the first 20 bytes.
42 */
43#define UNION_BASE_SZ 20
44#define FLAG_LINK (1u<<20)
46#define FLAG_CHECKED (1u<<21)
47struct delta_entry {
49 union delta_base base;
50 int obj_no;
51};
52static struct object_entry *objects;
54static struct delta_entry *deltas;
55static struct base_data *base_cache;
56static size_t base_cache_used;
57static int nr_objects;
58static int nr_deltas;
59static int nr_resolved_deltas;
60static int from_stdin;
62static int strict;
63static int verbose;
64static struct progress *progress;
66/* We always read in 4kB chunks. */
68static unsigned char input_buffer[4096];
69static unsigned int input_offset, input_len;
70static off_t consumed_bytes;
71static unsigned deepest_delta;
72static git_SHA_CTX input_ctx;
73static uint32_t input_crc32;
74static int input_fd, output_fd, pack_fd;
75static int mark_link(struct object *obj, int type, void *data)
77{
78 if (!obj)
79 return -1;
80 if (type != OBJ_ANY && obj->type != type)
82 die("object type mismatch at %s", sha1_to_hex(obj->sha1));
83 obj->flags |= FLAG_LINK;
85 return 0;
86}
87/* The content of each linked object must have been checked
89 or it must be already present in the object database */
90static void check_object(struct object *obj)
91{
92 if (!obj)
93 return;
94 if (!(obj->flags & FLAG_LINK))
96 return;
97 if (!(obj->flags & FLAG_CHECKED)) {
99 unsigned long size;
100 int type = sha1_object_info(obj->sha1, &size);
101 if (type != obj->type || type <= 0)
102 die("object of unexpected type");
103 obj->flags |= FLAG_CHECKED;
104 return;
105 }
106}
107static void check_objects(void)
109{
110 unsigned i, max;
111 max = get_max_object_index();
113 for (i = 0; i < max; i++)
114 check_object(get_indexed_object(i));
115}
116/* Discard current buffer used content. */
119static void flush(void)
120{
121 if (input_offset) {
122 if (output_fd >= 0)
123 write_or_die(output_fd, input_buffer, input_offset);
124 git_SHA1_Update(&input_ctx, input_buffer, input_offset);
125 memmove(input_buffer, input_buffer + input_offset, input_len);
126 input_offset = 0;
127 }
128}
129/*
131 * Make sure at least "min" bytes are available in the buffer, and
132 * return the pointer to the buffer.
133 */
134static void *fill(int min)
135{
136 if (min <= input_len)
137 return input_buffer + input_offset;
138 if (min > sizeof(input_buffer))
139 die("cannot fill %d bytes", min);
140 flush();
141 do {
142 ssize_t ret = xread(input_fd, input_buffer + input_len,
143 sizeof(input_buffer) - input_len);
144 if (ret <= 0) {
145 if (!ret)
146 die("early EOF");
147 die_errno("read error on input");
148 }
149 input_len += ret;
150 if (from_stdin)
151 display_throughput(progress, consumed_bytes + input_len);
152 } while (input_len < min);
153 return input_buffer;
154}
155static void use(int bytes)
157{
158 if (bytes > input_len)
159 die("used more bytes than were available");
160 input_crc32 = crc32(input_crc32, input_buffer + input_offset, bytes);
161 input_len -= bytes;
162 input_offset += bytes;
163 /* make sure off_t is sufficiently large not to wrap */
165 if (signed_add_overflows(consumed_bytes, bytes))
166 die("pack too large for current definition of off_t");
167 consumed_bytes += bytes;
168}
169static const char *open_pack_file(const char *pack_name)
171{
172 if (from_stdin) {
173 input_fd = 0;
174 if (!pack_name) {
175 static char tmp_file[PATH_MAX];
176 output_fd = odb_mkstemp(tmp_file, sizeof(tmp_file),
177 "pack/tmp_pack_XXXXXX");
178 pack_name = xstrdup(tmp_file);
179 } else
180 output_fd = open(pack_name, O_CREAT|O_EXCL|O_RDWR, 0600);
181 if (output_fd < 0)
182 die_errno("unable to create '%s'", pack_name);
183 pack_fd = output_fd;
184 } else {
185 input_fd = open(pack_name, O_RDONLY);
186 if (input_fd < 0)
187 die_errno("cannot open packfile '%s'", pack_name);
188 output_fd = -1;
189 pack_fd = input_fd;
190 }
191 git_SHA1_Init(&input_ctx);
192 return pack_name;
193}
194static void parse_pack_header(void)
196{
197 struct pack_header *hdr = fill(sizeof(struct pack_header));
198 /* Header consistency check */
200 if (hdr->hdr_signature != htonl(PACK_SIGNATURE))
201 die("pack signature mismatch");
202 if (!pack_version_ok(hdr->hdr_version))
203 die("pack version %"PRIu32" unsupported",
204 ntohl(hdr->hdr_version));
205 nr_objects = ntohl(hdr->hdr_entries);
207 use(sizeof(struct pack_header));
208}
209static NORETURN void bad_object(unsigned long offset, const char *format,
211 ...) __attribute__((format (printf, 2, 3)));
212static NORETURN void bad_object(unsigned long offset, const char *format, ...)
214{
215 va_list params;
216 char buf[1024];
217 va_start(params, format);
219 vsnprintf(buf, sizeof(buf), format, params);
220 va_end(params);
221 die("pack has bad object at offset %lu: %s", offset, buf);
222}
223static void free_base_data(struct base_data *c)
225{
226 if (c->data) {
227 free(c->data);
228 c->data = NULL;
229 base_cache_used -= c->size;
230 }
231}
232static void prune_base_data(struct base_data *retain)
234{
235 struct base_data *b;
236 for (b = base_cache;
237 base_cache_used > delta_base_cache_limit && b;
238 b = b->child) {
239 if (b->data && b != retain)
240 free_base_data(b);
241 }
242}
243static void link_base_data(struct base_data *base, struct base_data *c)
245{
246 if (base)
247 base->child = c;
248 else
249 base_cache = c;
250 c->base = base;
252 c->child = NULL;
253 if (c->data)
254 base_cache_used += c->size;
255 prune_base_data(c);
256}
257static void unlink_base_data(struct base_data *c)
259{
260 struct base_data *base = c->base;
261 if (base)
262 base->child = NULL;
263 else
264 base_cache = NULL;
265 free_base_data(c);
266}
267static void *unpack_entry_data(unsigned long offset, unsigned long size)
269{
270 int status;
271 git_zstream stream;
272 void *buf = xmalloc(size);
273 memset(&stream, 0, sizeof(stream));
275 git_inflate_init(&stream);
276 stream.next_out = buf;
277 stream.avail_out = size;
278 do {
280 stream.next_in = fill(1);
281 stream.avail_in = input_len;
282 status = git_inflate(&stream, 0);
283 use(input_len - stream.avail_in);
284 } while (status == Z_OK);
285 if (stream.total_out != size || status != Z_STREAM_END)
286 bad_object(offset, "inflate returned %d", status);
287 git_inflate_end(&stream);
288 return buf;
289}
290static void *unpack_raw_entry(struct object_entry *obj, union delta_base *delta_base)
292{
293 unsigned char *p;
294 unsigned long size, c;
295 off_t base_offset;
296 unsigned shift;
297 void *data;
298 obj->idx.offset = consumed_bytes;
300 input_crc32 = crc32(0, NULL, 0);
301 p = fill(1);
303 c = *p;
304 use(1);
305 obj->type = (c >> 4) & 7;
306 size = (c & 15);
307 shift = 4;
308 while (c & 0x80) {
309 p = fill(1);
310 c = *p;
311 use(1);
312 size += (c & 0x7f) << shift;
313 shift += 7;
314 }
315 obj->size = size;
316 switch (obj->type) {
318 case OBJ_REF_DELTA:
319 hashcpy(delta_base->sha1, fill(20));
320 use(20);
321 break;
322 case OBJ_OFS_DELTA:
323 memset(delta_base, 0, sizeof(*delta_base));
324 p = fill(1);
325 c = *p;
326 use(1);
327 base_offset = c & 127;
328 while (c & 128) {
329 base_offset += 1;
330 if (!base_offset || MSB(base_offset, 7))
331 bad_object(obj->idx.offset, "offset value overflow for delta base object");
332 p = fill(1);
333 c = *p;
334 use(1);
335 base_offset = (base_offset << 7) + (c & 127);
336 }
337 delta_base->offset = obj->idx.offset - base_offset;
338 if (delta_base->offset <= 0 || delta_base->offset >= obj->idx.offset)
339 bad_object(obj->idx.offset, "delta base offset is out of bound");
340 break;
341 case OBJ_COMMIT:
342 case OBJ_TREE:
343 case OBJ_BLOB:
344 case OBJ_TAG:
345 break;
346 default:
347 bad_object(obj->idx.offset, "unknown object type %d", obj->type);
348 }
349 obj->hdr_size = consumed_bytes - obj->idx.offset;
350 data = unpack_entry_data(obj->idx.offset, obj->size);
352 obj->idx.crc32 = input_crc32;
353 return data;
354}
355static void *get_data_from_pack(struct object_entry *obj)
357{
358 off_t from = obj[0].idx.offset + obj[0].hdr_size;
359 unsigned long len = obj[1].idx.offset - from;
360 unsigned char *data, *inbuf;
361 git_zstream stream;
362 int status;
363 data = xmalloc(obj->size);
365 inbuf = xmalloc((len < 64*1024) ? len : 64*1024);
366 memset(&stream, 0, sizeof(stream));
368 git_inflate_init(&stream);
369 stream.next_out = data;
370 stream.avail_out = obj->size;
371 do {
373 ssize_t n = (len < 64*1024) ? len : 64*1024;
374 n = pread(pack_fd, inbuf, n, from);
375 if (n < 0)
376 die_errno("cannot pread pack file");
377 if (!n)
378 die("premature end of pack file, %lu bytes missing", len);
379 from += n;
380 len -= n;
381 stream.next_in = inbuf;
382 stream.avail_in = n;
383 status = git_inflate(&stream, 0);
384 } while (len && status == Z_OK && !stream.avail_in);
385 /* This has been inflated OK when first encountered, so... */
387 if (status != Z_STREAM_END || stream.total_out != obj->size)
388 die("serious inflate inconsistency");
389 git_inflate_end(&stream);
391 free(inbuf);
392 return data;
393}
394static int compare_delta_bases(const union delta_base *base1,
396 const union delta_base *base2,
397 enum object_type type1,
398 enum object_type type2)
399{
400 int cmp = type1 - type2;
401 if (cmp)
402 return cmp;
403 return memcmp(base1, base2, UNION_BASE_SZ);
404}
405static int find_delta(const union delta_base *base, enum object_type type)
407{
408 int first = 0, last = nr_deltas;
409 while (first < last) {
411 int next = (first + last) / 2;
412 struct delta_entry *delta = &deltas[next];
413 int cmp;
414 cmp = compare_delta_bases(base, &delta->base,
416 type, objects[delta->obj_no].type);
417 if (!cmp)
418 return next;
419 if (cmp < 0) {
420 last = next;
421 continue;
422 }
423 first = next+1;
424 }
425 return -first-1;
426}
427static void find_delta_children(const union delta_base *base,
429 int *first_index, int *last_index,
430 enum object_type type)
431{
432 int first = find_delta(base, type);
433 int last = first;
434 int end = nr_deltas - 1;
435 if (first < 0) {
437 *first_index = 0;
438 *last_index = -1;
439 return;
440 }
441 while (first > 0 && !memcmp(&deltas[first - 1].base, base, UNION_BASE_SZ))
442 --first;
443 while (last < end && !memcmp(&deltas[last + 1].base, base, UNION_BASE_SZ))
444 ++last;
445 *first_index = first;
446 *last_index = last;
447}
448static void sha1_object(const void *data, unsigned long size,
450 enum object_type type, unsigned char *sha1)
451{
452 hash_sha1_file(data, size, typename(type), sha1);
453 if (has_sha1_file(sha1)) {
454 void *has_data;
455 enum object_type has_type;
456 unsigned long has_size;
457 has_data = read_sha1_file(sha1, &has_type, &has_size);
458 if (!has_data)
459 die("cannot read existing object %s", sha1_to_hex(sha1));
460 if (size != has_size || type != has_type ||
461 memcmp(data, has_data, size) != 0)
462 die("SHA1 COLLISION FOUND WITH %s !", sha1_to_hex(sha1));
463 free(has_data);
464 }
465 if (strict) {
466 if (type == OBJ_BLOB) {
467 struct blob *blob = lookup_blob(sha1);
468 if (blob)
469 blob->object.flags |= FLAG_CHECKED;
470 else
471 die("invalid blob object %s", sha1_to_hex(sha1));
472 } else {
473 struct object *obj;
474 int eaten;
475 void *buf = (void *) data;
476 /*
478 * we do not need to free the memory here, as the
479 * buf is deleted by the caller.
480 */
481 obj = parse_object_buffer(sha1, type, size, buf, &eaten);
482 if (!obj)
483 die("invalid %s", typename(type));
484 if (fsck_object(obj, 1, fsck_error_function))
485 die("Error in object");
486 if (fsck_walk(obj, mark_link, NULL))
487 die("Not all child objects of %s are reachable", sha1_to_hex(obj->sha1));
488 if (obj->type == OBJ_TREE) {
490 struct tree *item = (struct tree *) obj;
491 item->buffer = NULL;
492 }
493 if (obj->type == OBJ_COMMIT) {
494 struct commit *commit = (struct commit *) obj;
495 commit->buffer = NULL;
496 }
497 obj->flags |= FLAG_CHECKED;
498 }
499 }
500}
501static int is_delta_type(enum object_type type)
503{
504 return (type == OBJ_REF_DELTA || type == OBJ_OFS_DELTA);
505}
506static void *get_base_data(struct base_data *c)
508{
509 if (!c->data) {
510 struct object_entry *obj = c->obj;
511 if (is_delta_type(obj->type)) {
513 void *base = get_base_data(c->base);
514 void *raw = get_data_from_pack(obj);
515 c->data = patch_delta(
516 base, c->base->size,
517 raw, obj->size,
518 &c->size);
519 free(raw);
520 if (!c->data)
521 bad_object(obj->idx.offset, "failed to apply delta");
522 } else {
523 c->data = get_data_from_pack(obj);
524 c->size = obj->size;
525 }
526 base_cache_used += c->size;
528 prune_base_data(c);
529 }
530 return c->data;
531}
532static void resolve_delta(struct object_entry *delta_obj,
534 struct base_data *base, struct base_data *result)
535{
536 void *base_data, *delta_data;
537 delta_obj->real_type = base->obj->real_type;
539 delta_obj->delta_depth = base->obj->delta_depth + 1;
540 if (deepest_delta < delta_obj->delta_depth)
541 deepest_delta = delta_obj->delta_depth;
542 delta_obj->base_object_no = base->obj - objects;
543 delta_data = get_data_from_pack(delta_obj);
544 base_data = get_base_data(base);
545 result->obj = delta_obj;
546 result->data = patch_delta(base_data, base->size,
547 delta_data, delta_obj->size, &result->size);
548 free(delta_data);
549 if (!result->data)
550 bad_object(delta_obj->idx.offset, "failed to apply delta");
551 sha1_object(result->data, result->size, delta_obj->real_type,
552 delta_obj->idx.sha1);
553 nr_resolved_deltas++;
554}
555static void find_unresolved_deltas(struct base_data *base,
557 struct base_data *prev_base)
558{
559 int i, ref_first, ref_last, ofs_first, ofs_last;
560 /*
562 * This is a recursive function. Those brackets should help reducing
563 * stack usage by limiting the scope of the delta_base union.
564 */
565 {
566 union delta_base base_spec;
567 hashcpy(base_spec.sha1, base->obj->idx.sha1);
569 find_delta_children(&base_spec,
570 &ref_first, &ref_last, OBJ_REF_DELTA);
571 memset(&base_spec, 0, sizeof(base_spec));
573 base_spec.offset = base->obj->idx.offset;
574 find_delta_children(&base_spec,
575 &ofs_first, &ofs_last, OBJ_OFS_DELTA);
576 }
577 if (ref_last == -1 && ofs_last == -1) {
579 free(base->data);
580 return;
581 }
582 link_base_data(prev_base, base);
584 for (i = ref_first; i <= ref_last; i++) {
586 struct object_entry *child = objects + deltas[i].obj_no;
587 struct base_data result;
588 assert(child->real_type == OBJ_REF_DELTA);
590 resolve_delta(child, base, &result);
591 if (i == ref_last && ofs_last == -1)
592 free_base_data(base);
593 find_unresolved_deltas(&result, base);
594 }
595 for (i = ofs_first; i <= ofs_last; i++) {
597 struct object_entry *child = objects + deltas[i].obj_no;
598 struct base_data result;
599 assert(child->real_type == OBJ_OFS_DELTA);
601 resolve_delta(child, base, &result);
602 if (i == ofs_last)
603 free_base_data(base);
604 find_unresolved_deltas(&result, base);
605 }
606 unlink_base_data(base);
608}
609static int compare_delta_entry(const void *a, const void *b)
611{
612 const struct delta_entry *delta_a = a;
613 const struct delta_entry *delta_b = b;
614 /* group by type (ref vs ofs) and then by value (sha-1 or offset) */
616 return compare_delta_bases(&delta_a->base, &delta_b->base,
617 objects[delta_a->obj_no].type,
618 objects[delta_b->obj_no].type);
619}
620/* Parse all objects and return the pack content SHA1 hash */
622static void parse_pack_objects(unsigned char *sha1)
623{
624 int i;
625 struct delta_entry *delta = deltas;
626 struct stat st;
627 /*
629 * First pass:
630 * - find locations of all objects;
631 * - calculate SHA1 of all non-delta objects;
632 * - remember base (SHA1 or offset) for all deltas.
633 */
634 if (verbose)
635 progress = start_progress(
636 from_stdin ? "Receiving objects" : "Indexing objects",
637 nr_objects);
638 for (i = 0; i < nr_objects; i++) {
639 struct object_entry *obj = &objects[i];
640 void *data = unpack_raw_entry(obj, &delta->base);
641 obj->real_type = obj->type;
642 if (is_delta_type(obj->type)) {
643 nr_deltas++;
644 delta->obj_no = i;
645 delta++;
646 } else
647 sha1_object(data, obj->size, obj->type, obj->idx.sha1);
648 free(data);
649 display_progress(progress, i+1);
650 }
651 objects[i].idx.offset = consumed_bytes;
652 stop_progress(&progress);
653 /* Check pack integrity */
655 flush();
656 git_SHA1_Final(sha1, &input_ctx);
657 if (hashcmp(fill(20), sha1))
658 die("pack is corrupted (SHA1 mismatch)");
659 use(20);
660 /* If input_fd is a file, we should have reached its end now. */
662 if (fstat(input_fd, &st))
663 die_errno("cannot fstat packfile");
664 if (S_ISREG(st.st_mode) &&
665 lseek(input_fd, 0, SEEK_CUR) - input_len != st.st_size)
666 die("pack has junk at the end");
667 if (!nr_deltas)
669 return;
670 /* Sort deltas by base SHA1/offset for fast searching */
672 qsort(deltas, nr_deltas, sizeof(struct delta_entry),
673 compare_delta_entry);
674 /*
676 * Second pass:
677 * - for all non-delta objects, look if it is used as a base for
678 * deltas;
679 * - if used as a base, uncompress the object and apply all deltas,
680 * recursively checking if the resulting object is used as a base
681 * for some more deltas.
682 */
683 if (verbose)
684 progress = start_progress("Resolving deltas", nr_deltas);
685 for (i = 0; i < nr_objects; i++) {
686 struct object_entry *obj = &objects[i];
687 struct base_data base_obj;
688 if (is_delta_type(obj->type))
690 continue;
691 base_obj.obj = obj;
692 base_obj.data = NULL;
693 find_unresolved_deltas(&base_obj, NULL);
694 display_progress(progress, nr_resolved_deltas);
695 }
696}
697static int write_compressed(struct sha1file *f, void *in, unsigned int size)
699{
700 git_zstream stream;
701 int status;
702 unsigned char outbuf[4096];
703 memset(&stream, 0, sizeof(stream));
705 git_deflate_init(&stream, zlib_compression_level);
706 stream.next_in = in;
707 stream.avail_in = size;
708 do {
710 stream.next_out = outbuf;
711 stream.avail_out = sizeof(outbuf);
712 status = git_deflate(&stream, Z_FINISH);
713 sha1write(f, outbuf, sizeof(outbuf) - stream.avail_out);
714 } while (status == Z_OK);
715 if (status != Z_STREAM_END)
717 die("unable to deflate appended object (%d)", status);
718 size = stream.total_out;
719 git_deflate_end(&stream);
720 return size;
721}
722static struct object_entry *append_obj_to_pack(struct sha1file *f,
724 const unsigned char *sha1, void *buf,
725 unsigned long size, enum object_type type)
726{
727 struct object_entry *obj = &objects[nr_objects++];
728 unsigned char header[10];
729 unsigned long s = size;
730 int n = 0;
731 unsigned char c = (type << 4) | (s & 15);
732 s >>= 4;
733 while (s) {
734 header[n++] = c | 0x80;
735 c = s & 0x7f;
736 s >>= 7;
737 }
738 header[n++] = c;
739 crc32_begin(f);
740 sha1write(f, header, n);
741 obj[0].size = size;
742 obj[0].hdr_size = n;
743 obj[0].type = type;
744 obj[0].real_type = type;
745 obj[1].idx.offset = obj[0].idx.offset + n;
746 obj[1].idx.offset += write_compressed(f, buf, size);
747 obj[0].idx.crc32 = crc32_end(f);
748 sha1flush(f);
749 hashcpy(obj->idx.sha1, sha1);
750 return obj;
751}
752static int delta_pos_compare(const void *_a, const void *_b)
754{
755 struct delta_entry *a = *(struct delta_entry **)_a;
756 struct delta_entry *b = *(struct delta_entry **)_b;
757 return a->obj_no - b->obj_no;
758}
759static void fix_unresolved_deltas(struct sha1file *f, int nr_unresolved)
761{
762 struct delta_entry **sorted_by_pos;
763 int i, n = 0;
764 /*
766 * Since many unresolved deltas may well be themselves base objects
767 * for more unresolved deltas, we really want to include the
768 * smallest number of base objects that would cover as much delta
769 * as possible by picking the
770 * trunc deltas first, allowing for other deltas to resolve without
771 * additional base objects. Since most base objects are to be found
772 * before deltas depending on them, a good heuristic is to start
773 * resolving deltas in the same order as their position in the pack.
774 */
775 sorted_by_pos = xmalloc(nr_unresolved * sizeof(*sorted_by_pos));
776 for (i = 0; i < nr_deltas; i++) {
777 if (objects[deltas[i].obj_no].real_type != OBJ_REF_DELTA)
778 continue;
779 sorted_by_pos[n++] = &deltas[i];
780 }
781 qsort(sorted_by_pos, n, sizeof(*sorted_by_pos), delta_pos_compare);
782 for (i = 0; i < n; i++) {
784 struct delta_entry *d = sorted_by_pos[i];
785 enum object_type type;
786 struct base_data base_obj;
787 if (objects[d->obj_no].real_type != OBJ_REF_DELTA)
789 continue;
790 base_obj.data = read_sha1_file(d->base.sha1, &type, &base_obj.size);
791 if (!base_obj.data)
792 continue;
793 if (check_sha1_signature(d->base.sha1, base_obj.data,
795 base_obj.size, typename(type)))
796 die("local object %s is corrupt", sha1_to_hex(d->base.sha1));
797 base_obj.obj = append_obj_to_pack(f, d->base.sha1,
798 base_obj.data, base_obj.size, type);
799 find_unresolved_deltas(&base_obj, NULL);
800 display_progress(progress, nr_resolved_deltas);
801 }
802 free(sorted_by_pos);
803}
804static void final(const char *final_pack_name, const char *curr_pack_name,
806 const char *final_index_name, const char *curr_index_name,
807 const char *keep_name, const char *keep_msg,
808 unsigned char *sha1)
809{
810 const char *report = "pack";
811 char name[PATH_MAX];
812 int err;
813 if (!from_stdin) {
815 close(input_fd);
816 } else {
817 fsync_or_die(output_fd, curr_pack_name);
818 err = close(output_fd);
819 if (err)
820 die_errno("error while closing pack file");
821 }
822 if (keep_msg) {
824 int keep_fd, keep_msg_len = strlen(keep_msg);
825 if (!keep_name)
827 keep_fd = odb_pack_keep(name, sizeof(name), sha1);
828 else
829 keep_fd = open(keep_name, O_RDWR|O_CREAT|O_EXCL, 0600);
830 if (keep_fd < 0) {
832 if (errno != EEXIST)
833 die_errno("cannot write keep file '%s'",
834 keep_name);
835 } else {
836 if (keep_msg_len > 0) {
837 write_or_die(keep_fd, keep_msg, keep_msg_len);
838 write_or_die(keep_fd, "\n", 1);
839 }
840 if (close(keep_fd) != 0)
841 die_errno("cannot close written keep file '%s'",
842 keep_name);
843 report = "keep";
844 }
845 }
846 if (final_pack_name != curr_pack_name) {
848 if (!final_pack_name) {
849 snprintf(name, sizeof(name), "%s/pack/pack-%s.pack",
850 get_object_directory(), sha1_to_hex(sha1));
851 final_pack_name = name;
852 }
853 if (move_temp_to_file(curr_pack_name, final_pack_name))
854 die("cannot store pack file");
855 } else if (from_stdin)
856 chmod(final_pack_name, 0444);
857 if (final_index_name != curr_index_name) {
859 if (!final_index_name) {
860 snprintf(name, sizeof(name), "%s/pack/pack-%s.idx",
861 get_object_directory(), sha1_to_hex(sha1));
862 final_index_name = name;
863 }
864 if (move_temp_to_file(curr_index_name, final_index_name))
865 die("cannot store index file");
866 } else
867 chmod(final_index_name, 0444);
868 if (!from_stdin) {
870 printf("%s\n", sha1_to_hex(sha1));
871 } else {
872 char buf[48];
873 int len = snprintf(buf, sizeof(buf), "%s\t%s\n",
874 report, sha1_to_hex(sha1));
875 write_or_die(1, buf, len);
876 /*
878 * Let's just mimic git-unpack-objects here and write
879 * the last part of the input buffer to stdout.
880 */
881 while (input_len) {
882 err = xwrite(1, input_buffer + input_offset, input_len);
883 if (err <= 0)
884 break;
885 input_len -= err;
886 input_offset += err;
887 }
888 }
889}
890static int git_index_pack_config(const char *k, const char *v, void *cb)
892{
893 struct pack_idx_option *opts = cb;
894 if (!strcmp(k, "pack.indexversion")) {
896 opts->version = git_config_int(k, v);
897 if (opts->version > 2)
898 die("bad pack.indexversion=%"PRIu32, opts->version);
899 return 0;
900 }
901 return git_default_config(k, v, cb);
902}
903static int cmp_uint32(const void *a_, const void *b_)
905{
906 uint32_t a = *((uint32_t *)a_);
907 uint32_t b = *((uint32_t *)b_);
908 return (a < b) ? -1 : (a != b);
910}
911static void read_v2_anomalous_offsets(struct packed_git *p,
913 struct pack_idx_option *opts)
914{
915 const uint32_t *idx1, *idx2;
916 uint32_t i;
917 /* The address of the 4-byte offset table */
919 idx1 = (((const uint32_t *)p->index_data)
920 + 2 /* 8-byte header */
921 + 256 /* fan out */
922 + 5 * p->num_objects /* 20-byte SHA-1 table */
923 + p->num_objects /* CRC32 table */
924 );
925 /* The address of the 8-byte offset table */
927 idx2 = idx1 + p->num_objects;
928 for (i = 0; i < p->num_objects; i++) {
930 uint32_t off = ntohl(idx1[i]);
931 if (!(off & 0x80000000))
932 continue;
933 off = off & 0x7fffffff;
934 if (idx2[off * 2])
935 continue;
936 /*
937 * The real offset is ntohl(idx2[off * 2]) in high 4
938 * octets, and ntohl(idx2[off * 2 + 1]) in low 4
939 * octets. But idx2[off * 2] is Zero!!!
940 */
941 ALLOC_GROW(opts->anomaly, opts->anomaly_nr + 1, opts->anomaly_alloc);
942 opts->anomaly[opts->anomaly_nr++] = ntohl(idx2[off * 2 + 1]);
943 }
944 if (1 < opts->anomaly_nr)
946 qsort(opts->anomaly, opts->anomaly_nr, sizeof(uint32_t), cmp_uint32);
947}
948static void read_idx_option(struct pack_idx_option *opts, const char *pack_name)
950{
951 struct packed_git *p = add_packed_git(pack_name, strlen(pack_name), 1);
952 if (!p)
954 die("Cannot open existing pack file '%s'", pack_name);
955 if (open_pack_index(p))
956 die("Cannot open existing pack idx file for '%s'", pack_name);
957 /* Read the attributes from the existing idx file */
959 opts->version = p->index_version;
960 if (opts->version == 2)
962 read_v2_anomalous_offsets(p, opts);
963 /*
965 * Get rid of the idx file as we do not need it anymore.
966 * NEEDSWORK: extract this bit from free_pack_by_name() in
967 * sha1_file.c, perhaps? It shouldn't matter very much as we
968 * know we haven't installed this pack (hence we never have
969 * read anything from it).
970 */
971 close_pack_index(p);
972 free(p);
973}
974static void show_pack_info(int stat_only)
976{
977 int i, baseobjects = nr_objects - nr_deltas;
978 unsigned long *chain_histogram = NULL;
979 if (deepest_delta)
981 chain_histogram = xcalloc(deepest_delta, sizeof(unsigned long));
982 for (i = 0; i < nr_objects; i++) {
984 struct object_entry *obj = &objects[i];
985 if (is_delta_type(obj->type))
987 chain_histogram[obj->delta_depth - 1]++;
988 if (stat_only)
989 continue;
990 printf("%s %-6s %lu %lu %"PRIuMAX,
991 sha1_to_hex(obj->idx.sha1),
992 typename(obj->real_type), obj->size,
993 (unsigned long)(obj[1].idx.offset - obj->idx.offset),
994 (uintmax_t)obj->idx.offset);
995 if (is_delta_type(obj->type)) {
996 struct object_entry *bobj = &objects[obj->base_object_no];
997 printf(" %u %s", obj->delta_depth, sha1_to_hex(bobj->idx.sha1));
998 }
999 putchar('\n');
1000 }
1001 if (baseobjects)
1003 printf("non delta: %d object%s\n",
1004 baseobjects, baseobjects > 1 ? "s" : "");
1005 for (i = 0; i < deepest_delta; i++) {
1006 if (!chain_histogram[i])
1007 continue;
1008 printf("chain length = %d: %lu object%s\n",
1009 i + 1,
1010 chain_histogram[i],
1011 chain_histogram[i] > 1 ? "s" : "");
1012 }
1013}
1014int cmd_index_pack(int argc, const char **argv, const char *prefix)
1016{
1017 int i, fix_thin_pack = 0, verify = 0, stat_only = 0, stat = 0;
1018 const char *curr_pack, *curr_index;
1019 const char *index_name = NULL, *pack_name = NULL;
1020 const char *keep_name = NULL, *keep_msg = NULL;
1021 char *index_name_buf = NULL, *keep_name_buf = NULL;
1022 struct pack_idx_entry **idx_objects;
1023 struct pack_idx_option opts;
1024 unsigned char pack_sha1[20];
1025 if (argc == 2 && !strcmp(argv[1], "-h"))
1027 usage(index_pack_usage);
1028 read_replace_refs = 0;
1030 reset_pack_idx_option(&opts);
1032 git_config(git_index_pack_config, &opts);
1033 if (prefix && chdir(prefix))
1034 die("Cannot come back to cwd");
1035 for (i = 1; i < argc; i++) {
1037 const char *arg = argv[i];
1038 if (*arg == '-') {
1040 if (!strcmp(arg, "--stdin")) {
1041 from_stdin = 1;
1042 } else if (!strcmp(arg, "--fix-thin")) {
1043 fix_thin_pack = 1;
1044 } else if (!strcmp(arg, "--strict")) {
1045 strict = 1;
1046 } else if (!strcmp(arg, "--verify")) {
1047 verify = 1;
1048 } else if (!strcmp(arg, "--verify-stat")) {
1049 verify = 1;
1050 stat = 1;
1051 } else if (!strcmp(arg, "--verify-stat-only")) {
1052 verify = 1;
1053 stat = 1;
1054 stat_only = 1;
1055 } else if (!strcmp(arg, "--keep")) {
1056 keep_msg = "";
1057 } else if (!prefixcmp(arg, "--keep=")) {
1058 keep_msg = arg + 7;
1059 } else if (!prefixcmp(arg, "--pack_header=")) {
1060 struct pack_header *hdr;
1061 char *c;
1062 hdr = (struct pack_header *)input_buffer;
1064 hdr->hdr_signature = htonl(PACK_SIGNATURE);
1065 hdr->hdr_version = htonl(strtoul(arg + 14, &c, 10));
1066 if (*c != ',')
1067 die("bad %s", arg);
1068 hdr->hdr_entries = htonl(strtoul(c + 1, &c, 10));
1069 if (*c)
1070 die("bad %s", arg);
1071 input_len = sizeof(*hdr);
1072 } else if (!strcmp(arg, "-v")) {
1073 verbose = 1;
1074 } else if (!strcmp(arg, "-o")) {
1075 if (index_name || (i+1) >= argc)
1076 usage(index_pack_usage);
1077 index_name = argv[++i];
1078 } else if (!prefixcmp(arg, "--index-version=")) {
1079 char *c;
1080 opts.version = strtoul(arg + 16, &c, 10);
1081 if (opts.version > 2)
1082 die("bad %s", arg);
1083 if (*c == ',')
1084 opts.off32_limit = strtoul(c+1, &c, 0);
1085 if (*c || opts.off32_limit & 0x80000000)
1086 die("bad %s", arg);
1087 } else
1088 usage(index_pack_usage);
1089 continue;
1090 }
1091 if (pack_name)
1093 usage(index_pack_usage);
1094 pack_name = arg;
1095 }
1096 if (!pack_name && !from_stdin)
1098 usage(index_pack_usage);
1099 if (fix_thin_pack && !from_stdin)
1100 die("--fix-thin cannot be used without --stdin");
1101 if (!index_name && pack_name) {
1102 int len = strlen(pack_name);
1103 if (!has_extension(pack_name, ".pack"))
1104 die("packfile name '%s' does not end with '.pack'",
1105 pack_name);
1106 index_name_buf = xmalloc(len);
1107 memcpy(index_name_buf, pack_name, len - 5);
1108 strcpy(index_name_buf + len - 5, ".idx");
1109 index_name = index_name_buf;
1110 }
1111 if (keep_msg && !keep_name && pack_name) {
1112 int len = strlen(pack_name);
1113 if (!has_extension(pack_name, ".pack"))
1114 die("packfile name '%s' does not end with '.pack'",
1115 pack_name);
1116 keep_name_buf = xmalloc(len);
1117 memcpy(keep_name_buf, pack_name, len - 5);
1118 strcpy(keep_name_buf + len - 5, ".keep");
1119 keep_name = keep_name_buf;
1120 }
1121 if (verify) {
1122 if (!index_name)
1123 die("--verify with no packfile name given");
1124 read_idx_option(&opts, index_name);
1125 opts.flags |= WRITE_IDX_VERIFY | WRITE_IDX_STRICT;
1126 }
1127 if (strict)
1128 opts.flags |= WRITE_IDX_STRICT;
1129 curr_pack = open_pack_file(pack_name);
1131 parse_pack_header();
1132 objects = xcalloc(nr_objects + 1, sizeof(struct object_entry));
1133 deltas = xcalloc(nr_objects, sizeof(struct delta_entry));
1134 parse_pack_objects(pack_sha1);
1135 if (nr_deltas == nr_resolved_deltas) {
1136 stop_progress(&progress);
1137 /* Flush remaining pack final 20-byte SHA1. */
1138 flush();
1139 } else {
1140 if (fix_thin_pack) {
1141 struct sha1file *f;
1142 unsigned char read_sha1[20], tail_sha1[20];
1143 char msg[48];
1144 int nr_unresolved = nr_deltas - nr_resolved_deltas;
1145 int nr_objects_initial = nr_objects;
1146 if (nr_unresolved <= 0)
1147 die("confusion beyond insanity");
1148 objects = xrealloc(objects,
1149 (nr_objects + nr_unresolved + 1)
1150 * sizeof(*objects));
1151 f = sha1fd(output_fd, curr_pack);
1152 fix_unresolved_deltas(f, nr_unresolved);
1153 sprintf(msg, "completed with %d local objects",
1154 nr_objects - nr_objects_initial);
1155 stop_progress_msg(&progress, msg);
1156 sha1close(f, tail_sha1, 0);
1157 hashcpy(read_sha1, pack_sha1);
1158 fixup_pack_header_footer(output_fd, pack_sha1,
1159 curr_pack, nr_objects,
1160 read_sha1, consumed_bytes-20);
1161 if (hashcmp(read_sha1, tail_sha1) != 0)
1162 die("Unexpected tail checksum for %s "
1163 "(disk corruption?)", curr_pack);
1164 }
1165 if (nr_deltas != nr_resolved_deltas)
1166 die("pack has %d unresolved deltas",
1167 nr_deltas - nr_resolved_deltas);
1168 }
1169 free(deltas);
1170 if (strict)
1171 check_objects();
1172 if (stat)
1174 show_pack_info(stat_only);
1175 idx_objects = xmalloc((nr_objects) * sizeof(struct pack_idx_entry *));
1177 for (i = 0; i < nr_objects; i++)
1178 idx_objects[i] = &objects[i].idx;
1179 curr_index = write_idx_file(index_name, idx_objects, nr_objects, &opts, pack_sha1);
1180 free(idx_objects);
1181 if (!verify)
1183 final(pack_name, curr_pack,
1184 index_name, curr_index,
1185 keep_name, keep_msg,
1186 pack_sha1);
1187 else
1188 close(input_fd);
1189 free(objects);
1190 free(index_name_buf);
1191 free(keep_name_buf);
1192 if (pack_name == NULL)
1193 free((void *) curr_pack);
1194 if (index_name == NULL)
1195 free((void *) curr_index);
1196 return 0;
1198}