git/pack-check.c
Shawn O. Pearce c4001d92be Use off_t when we really mean a file offset.
Not all platforms have declared 'unsigned long' to be a 64 bit value,
but we want to support a 64 bit packfile (or close enough anyway)
in the near future as some projects are getting large enough that
their packed size exceeds 4 GiB.

By using off_t, the POSIX type that is declared to mean an offset
within a file, we support whatever maximum file size the underlying
operating system will handle.  For most modern systems this is up
around 2^60 or higher.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-03-07 11:06:25 -08:00

162 lines
4.2 KiB
C

#include "cache.h"
#include "pack.h"
static int verify_packfile(struct packed_git *p,
struct pack_window **w_curs)
{
off_t index_size = p->index_size;
void *index_base = p->index_base;
SHA_CTX ctx;
unsigned char sha1[20];
off_t offset = 0, pack_sig = p->pack_size - 20;
uint32_t nr_objects, i;
int err;
/* Note that the pack header checks are actually performed by
* use_pack when it first opens the pack file. If anything
* goes wrong during those checks then the call will die out
* immediately.
*/
SHA1_Init(&ctx);
while (offset < pack_sig) {
unsigned int remaining;
unsigned char *in = use_pack(p, w_curs, offset, &remaining);
offset += remaining;
if (offset > pack_sig)
remaining -= (unsigned int)(offset - pack_sig);
SHA1_Update(&ctx, in, remaining);
}
SHA1_Final(sha1, &ctx);
if (hashcmp(sha1, use_pack(p, w_curs, pack_sig, NULL)))
return error("Packfile %s SHA1 mismatch with itself",
p->pack_name);
if (hashcmp(sha1, (unsigned char *)index_base + index_size - 40))
return error("Packfile %s SHA1 mismatch with idx",
p->pack_name);
unuse_pack(w_curs);
/* Make sure everything reachable from idx is valid. Since we
* have verified that nr_objects matches between idx and pack,
* we do not do scan-streaming check on the pack file.
*/
nr_objects = num_packed_objects(p);
for (i = 0, err = 0; i < nr_objects; i++) {
unsigned char sha1[20];
void *data;
enum object_type type;
unsigned long size;
off_t offset;
if (nth_packed_object_sha1(p, i, sha1))
die("internal error pack-check nth-packed-object");
offset = find_pack_entry_one(sha1, p);
if (!offset)
die("internal error pack-check find-pack-entry-one");
data = unpack_entry(p, offset, &type, &size);
if (!data) {
err = error("cannot unpack %s from %s",
sha1_to_hex(sha1), p->pack_name);
continue;
}
if (check_sha1_signature(sha1, data, size, typename(type))) {
err = error("packed %s from %s is corrupt",
sha1_to_hex(sha1), p->pack_name);
free(data);
continue;
}
free(data);
}
return err;
}
#define MAX_CHAIN 40
static void show_pack_info(struct packed_git *p)
{
uint32_t nr_objects, i, chain_histogram[MAX_CHAIN];
nr_objects = num_packed_objects(p);
memset(chain_histogram, 0, sizeof(chain_histogram));
for (i = 0; i < nr_objects; i++) {
unsigned char sha1[20], base_sha1[20];
const char *type;
unsigned long size;
unsigned long store_size;
off_t offset;
unsigned int delta_chain_length;
if (nth_packed_object_sha1(p, i, sha1))
die("internal error pack-check nth-packed-object");
offset = find_pack_entry_one(sha1, p);
if (!offset)
die("internal error pack-check find-pack-entry-one");
type = packed_object_info_detail(p, offset, &size, &store_size,
&delta_chain_length,
base_sha1);
printf("%s ", sha1_to_hex(sha1));
if (!delta_chain_length)
printf("%-6s %lu %"PRIuMAX"\n",
type, size, (uintmax_t)offset);
else {
printf("%-6s %lu %"PRIuMAX" %u %s\n",
type, size, (uintmax_t)offset,
delta_chain_length, sha1_to_hex(base_sha1));
if (delta_chain_length < MAX_CHAIN)
chain_histogram[delta_chain_length]++;
else
chain_histogram[0]++;
}
}
for (i = 0; i < MAX_CHAIN; i++) {
if (!chain_histogram[i])
continue;
printf("chain length %s %d: %d object%s\n",
i ? "=" : ">=",
i ? i : MAX_CHAIN,
chain_histogram[i],
1 < chain_histogram[i] ? "s" : "");
}
}
int verify_pack(struct packed_git *p, int verbose)
{
off_t index_size = p->index_size;
void *index_base = p->index_base;
SHA_CTX ctx;
unsigned char sha1[20];
int ret;
ret = 0;
/* Verify SHA1 sum of the index file */
SHA1_Init(&ctx);
SHA1_Update(&ctx, index_base, (unsigned int)(index_size - 20));
SHA1_Final(sha1, &ctx);
if (hashcmp(sha1, (unsigned char *)index_base + index_size - 20))
ret = error("Packfile index for %s SHA1 mismatch",
p->pack_name);
if (!ret) {
/* Verify pack file */
struct pack_window *w_curs = NULL;
ret = verify_packfile(p, &w_curs);
unuse_pack(&w_curs);
}
if (verbose) {
if (ret)
printf("%s: bad\n", p->pack_name);
else {
show_pack_info(p);
printf("%s: ok\n", p->pack_name);
}
}
return ret;
}