git/pack-check.c
Junio C Hamano cf0b1793ea Merge branch 'sb/object-store'
Refactoring the internal global data structure to make it possible
to open multiple repositories, work with and then close them.

Rerolled by Duy on top of a separate preliminary clean-up topic.
The resulting structure of the topics looked very sensible.

* sb/object-store: (27 commits)
  sha1_file: allow sha1_loose_object_info to handle arbitrary repositories
  sha1_file: allow map_sha1_file to handle arbitrary repositories
  sha1_file: allow map_sha1_file_1 to handle arbitrary repositories
  sha1_file: allow open_sha1_file to handle arbitrary repositories
  sha1_file: allow stat_sha1_file to handle arbitrary repositories
  sha1_file: allow sha1_file_name to handle arbitrary repositories
  sha1_file: add repository argument to sha1_loose_object_info
  sha1_file: add repository argument to map_sha1_file
  sha1_file: add repository argument to map_sha1_file_1
  sha1_file: add repository argument to open_sha1_file
  sha1_file: add repository argument to stat_sha1_file
  sha1_file: add repository argument to sha1_file_name
  sha1_file: allow prepare_alt_odb to handle arbitrary repositories
  sha1_file: allow link_alt_odb_entries to handle arbitrary repositories
  sha1_file: add repository argument to prepare_alt_odb
  sha1_file: add repository argument to link_alt_odb_entries
  sha1_file: add repository argument to read_info_alternates
  sha1_file: add repository argument to link_alt_odb_entry
  sha1_file: add raw_object_store argument to alt_odb_usable
  pack: move approximate object count to object store
  ...
2018-04-11 13:09:55 +09:00

203 lines
5.5 KiB
C

#include "cache.h"
#include "pack.h"
#include "pack-revindex.h"
#include "progress.h"
#include "packfile.h"
#include "object-store.h"
struct idx_entry {
off_t offset;
union idx_entry_object {
const unsigned char *hash;
struct object_id *oid;
} oid;
unsigned int nr;
};
static int compare_entries(const void *e1, const void *e2)
{
const struct idx_entry *entry1 = e1;
const struct idx_entry *entry2 = e2;
if (entry1->offset < entry2->offset)
return -1;
if (entry1->offset > entry2->offset)
return 1;
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, NULL, 0);
do {
unsigned long 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 * (the_hash_algo->rawsz/4) + nr;
return data_crc != ntohl(*index_crc);
}
static int verify_packfile(struct packed_git *p,
struct pack_window **w_curs,
verify_fn fn,
struct progress *progress, uint32_t base_count)
{
off_t index_size = p->index_size;
const unsigned char *index_base = p->index_data;
git_hash_ctx ctx;
unsigned char hash[GIT_MAX_RAWSZ], *pack_sig;
off_t offset = 0, pack_sig_ofs = 0;
uint32_t nr_objects, i;
int err = 0;
struct idx_entry *entries;
if (!is_pack_valid(p))
return error("packfile %s cannot be accessed", p->pack_name);
the_hash_algo->init_fn(&ctx);
do {
unsigned long remaining;
unsigned char *in = use_pack(p, w_curs, offset, &remaining);
offset += remaining;
if (!pack_sig_ofs)
pack_sig_ofs = p->pack_size - the_hash_algo->rawsz;
if (offset > pack_sig_ofs)
remaining -= (unsigned int)(offset - pack_sig_ofs);
the_hash_algo->update_fn(&ctx, in, remaining);
} while (offset < pack_sig_ofs);
the_hash_algo->final_fn(hash, &ctx);
pack_sig = use_pack(p, w_curs, pack_sig_ofs, NULL);
if (hashcmp(hash, pack_sig))
err = error("%s pack checksum mismatch",
p->pack_name);
if (hashcmp(index_base + index_size - the_hash_algo->hexsz, pack_sig))
err = error("%s pack checksum does not match its index",
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 = p->num_objects;
ALLOC_ARRAY(entries, nr_objects + 1);
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].oid.hash = nth_packed_object_sha1(p, i);
if (!entries[i].oid.hash)
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, compare_entries);
for (i = 0; i < nr_objects; i++) {
void *data;
enum object_type type;
unsigned long size;
off_t curpos;
int data_valid;
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"",
oid_to_hex(entries[i].oid.oid),
p->pack_name, (uintmax_t)offset);
}
curpos = entries[i].offset;
type = unpack_object_header(p, w_curs, &curpos, &size);
unuse_pack(w_curs);
if (type == OBJ_BLOB && big_file_threshold <= size) {
/*
* Let check_object_signature() check it with
* the streaming interface; no point slurping
* the data in-core only to discard.
*/
data = NULL;
data_valid = 0;
} else {
data = unpack_entry(p, entries[i].offset, &type, &size);
data_valid = 1;
}
if (data_valid && !data)
err = error("cannot unpack %s from %s at offset %"PRIuMAX"",
oid_to_hex(entries[i].oid.oid), p->pack_name,
(uintmax_t)entries[i].offset);
else if (check_object_signature(entries[i].oid.oid, data, size, type_name(type)))
err = error("packed %s from %s is corrupt",
oid_to_hex(entries[i].oid.oid), p->pack_name);
else if (fn) {
int eaten = 0;
err |= fn(entries[i].oid.oid, type, size, data, &eaten);
if (eaten)
data = NULL;
}
if (((base_count + i) & 1023) == 0)
display_progress(progress, base_count + i);
free(data);
}
display_progress(progress, base_count + i);
free(entries);
return err;
}
int verify_pack_index(struct packed_git *p)
{
off_t index_size;
const unsigned char *index_base;
git_hash_ctx ctx;
unsigned char hash[GIT_MAX_RAWSZ];
int err = 0;
if (open_pack_index(p))
return error("packfile %s index not opened", p->pack_name);
index_size = p->index_size;
index_base = p->index_data;
/* Verify SHA1 sum of the index file */
the_hash_algo->init_fn(&ctx);
the_hash_algo->update_fn(&ctx, index_base, (unsigned int)(index_size - the_hash_algo->rawsz));
the_hash_algo->final_fn(hash, &ctx);
if (hashcmp(hash, index_base + index_size - the_hash_algo->rawsz))
err = error("Packfile index for %s hash mismatch",
p->pack_name);
return err;
}
int verify_pack(struct packed_git *p, verify_fn fn,
struct progress *progress, uint32_t base_count)
{
int err = 0;
struct pack_window *w_curs = NULL;
err |= verify_pack_index(p);
if (!p->index_data)
return -1;
err |= verify_packfile(p, &w_curs, fn, progress, base_count);
unuse_pack(&w_curs);
return err;
}