verify-pack: check packed object CRC when using index version 2

To do so, check_pack_crc() moved from builtin-pack-objects.c to
pack-check.c where it is more logical to share.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Nicolas Pitre 2008-06-24 23:19:02 -04:00 committed by Junio C Hamano
parent 77d3ecee85
commit c41a4a9468
3 changed files with 38 additions and 25 deletions

View File

@ -209,28 +209,6 @@ static int check_pack_inflate(struct packed_git *p,
stream.total_in == len) ? 0 : -1;
}
static int check_pack_crc(struct packed_git *p, struct pack_window **w_curs,
off_t offset, off_t len, unsigned int nr)
{
const uint32_t *index_crc;
uint32_t data_crc = crc32(0, Z_NULL, 0);
do {
unsigned int avail;
void *data = use_pack(p, w_curs, offset, &avail);
if (avail > len)
avail = len;
data_crc = crc32(data_crc, data, avail);
offset += avail;
len -= avail;
} while (len);
index_crc = p->index_data;
index_crc += 2 + 256 + p->num_objects * (20/4) + nr;
return data_crc != ntohl(*index_crc);
}
static void copy_pack_data(struct sha1file *f,
struct packed_git *p,
struct pack_window **w_curs,

View File

@ -4,8 +4,9 @@
struct idx_entry
{
const unsigned char *sha1;
off_t offset;
const unsigned char *sha1;
unsigned int nr;
};
static int compare_entries(const void *e1, const void *e2)
@ -19,6 +20,28 @@ static int compare_entries(const void *e1, const void *e2)
return 0;
}
int check_pack_crc(struct packed_git *p, struct pack_window **w_curs,
off_t offset, off_t len, unsigned int nr)
{
const uint32_t *index_crc;
uint32_t data_crc = crc32(0, Z_NULL, 0);
do {
unsigned int avail;
void *data = use_pack(p, w_curs, offset, &avail);
if (avail > len)
avail = len;
data_crc = crc32(data_crc, data, avail);
offset += avail;
len -= avail;
} while (len);
index_crc = p->index_data;
index_crc += 2 + 256 + p->num_objects * (20/4) + nr;
return data_crc != ntohl(*index_crc);
}
static int verify_packfile(struct packed_git *p,
struct pack_window **w_curs)
{
@ -61,13 +84,15 @@ static int verify_packfile(struct packed_git *p,
* we do not do scan-streaming check on the pack file.
*/
nr_objects = p->num_objects;
entries = xmalloc(nr_objects * sizeof(*entries));
entries = xmalloc((nr_objects + 1) * sizeof(*entries));
entries[nr_objects].offset = pack_sig_ofs;
/* first sort entries by pack offset, since unpacking them is more efficient that way */
for (i = 0; i < nr_objects; i++) {
entries[i].sha1 = nth_packed_object_sha1(p, i);
if (!entries[i].sha1)
die("internal error pack-check nth-packed-object");
entries[i].offset = nth_packed_object_offset(p, i);
entries[i].nr = i;
}
qsort(entries, nr_objects, sizeof(*entries), compare_entries);
@ -76,6 +101,16 @@ static int verify_packfile(struct packed_git *p,
enum object_type type;
unsigned long size;
if (p->index_version > 1) {
off_t offset = entries[i].offset;
off_t len = entries[i+1].offset - offset;
unsigned int nr = entries[i].nr;
if (check_pack_crc(p, w_curs, offset, len, nr))
err = error("index CRC mismatch for object %s "
"from %s at offset %"PRIuMAX"",
sha1_to_hex(entries[i].sha1),
p->pack_name, (uintmax_t)offset);
}
data = unpack_entry(p, entries[i].offset, &type, &size);
if (!data) {
err = error("cannot unpack %s from %s at offset %"PRIuMAX"",

2
pack.h
View File

@ -56,7 +56,7 @@ struct pack_idx_entry {
};
extern char *write_idx_file(char *index_name, struct pack_idx_entry **objects, int nr_objects, unsigned char *sha1);
extern int check_pack_crc(struct packed_git *p, struct pack_window **w_curs, off_t offset, off_t len, unsigned int nr);
extern int verify_pack(struct packed_git *);
extern void fixup_pack_header_footer(int, unsigned char *, const char *, uint32_t);
extern char *index_pack_lockfile(int fd);