#include "cache.h"
#include "pack.h"
#include "csum-file.h"
void reset_pack_idx_option(struct pack_idx_option *opts)
{
memset(opts, 0, sizeof(*opts));
opts->version = 2;
opts->off32_limit = 0x7fffffff;
}
static int sha1_compare(const void *_a, const void *_b)
{
struct pack_idx_entry *a = *(struct pack_idx_entry **)_a;
struct pack_idx_entry *b = *(struct pack_idx_entry **)_b;
return oidcmp(&a->oid, &b->oid);
}
static int cmp_uint32(const void *a_, const void *b_)
{
uint32_t a = *((uint32_t *)a_);
uint32_t b = *((uint32_t *)b_);
return (a < b) ? -1 : (a != b);
}
static int need_large_offset(off_t offset, const struct pack_idx_option *opts)
{
uint32_t ofsval;
if ((offset >> 31) || (opts->off32_limit < offset))
return 1;
if (!opts->anomaly_nr)
return 0;
ofsval = offset;
return !!bsearch(&ofsval, opts->anomaly, opts->anomaly_nr,
sizeof(ofsval), cmp_uint32);
}
const char *write_idx_file(const char *index_name, struct pack_idx_entry **objects,
int nr_objects, const struct pack_idx_option *opts,
const unsigned char *sha1)
{
struct hashfile *f;
struct pack_idx_entry **sorted_by_sha, **list, **last;
off_t last_obj_offset = 0;
uint32_t array[256];
int i, fd;
uint32_t index_version;
if (nr_objects) {
sorted_by_sha = objects;
list = sorted_by_sha;
last = sorted_by_sha + nr_objects;
for (i = 0; i < nr_objects; ++i) {
if (objects[i]->offset > last_obj_offset)
last_obj_offset = objects[i]->offset;
}
QSORT(sorted_by_sha, nr_objects, sha1_compare);
}
else
sorted_by_sha = list = last = NULL;
if (opts->flags & WRITE_IDX_VERIFY) {
assert(index_name);
f = hashfd_check(index_name);
} else {
if (!index_name) {
struct strbuf tmp_file = STRBUF_INIT;
fd = odb_mkstemp(&tmp_file, "pack/tmp_idx_XXXXXX");
index_name = strbuf_detach(&tmp_file, NULL);
} else {
unlink(index_name);
fd = open(index_name, O_CREAT|O_EXCL|O_WRONLY, 0600);
if (fd < 0)
die_errno("unable to create '%s'", index_name);
}
f = hashfd(fd, index_name);
}
index_version = need_large_offset(last_obj_offset, opts) ? 2 : opts->version;
if (index_version >= 2) {
struct pack_idx_header hdr;
hdr.idx_signature = htonl(PACK_IDX_SIGNATURE);
hdr.idx_version = htonl(index_version);
hashwrite(f, &hdr, sizeof(hdr));
}
for (i = 0; i < 256; i++) {
struct pack_idx_entry **next = list;
while (next < last) {
struct pack_idx_entry *obj = *next;
if (obj->oid.hash[0] != i)
break;
next++;
}
array[i] = htonl(next - sorted_by_sha);
list = next;
}
hashwrite(f, array, 256 * 4);
list = sorted_by_sha;
for (i = 0; i < nr_objects; i++) {
struct pack_idx_entry *obj = *list++;
if (index_version < 2) {
uint32_t offset = htonl(obj->offset);
hashwrite(f, &offset, 4);
}
hashwrite(f, obj->oid.hash, the_hash_algo->rawsz);
if ((opts->flags & WRITE_IDX_STRICT) &&
(i && !oidcmp(&list[-2]->oid, &obj->oid)))
die("The same object %s appears twice in the pack",
oid_to_hex(&obj->oid));
}
if (index_version >= 2) {
unsigned int nr_large_offset = 0;
list = sorted_by_sha;
for (i = 0; i < nr_objects; i++) {
struct pack_idx_entry *obj = *list++;
uint32_t crc32_val = htonl(obj->crc32);
hashwrite(f, &crc32_val, 4);
}
list = sorted_by_sha;
for (i = 0; i < nr_objects; i++) {
struct pack_idx_entry *obj = *list++;
uint32_t offset;
offset = (need_large_offset(obj->offset, opts)
? (0x80000000 | nr_large_offset++)
: obj->offset);
offset = htonl(offset);
hashwrite(f, &offset, 4);
}
list = sorted_by_sha;
while (nr_large_offset) {
struct pack_idx_entry *obj = *list++;
uint64_t offset = obj->offset;
uint32_t split[2];
if (!need_large_offset(offset, opts))
continue;
split[0] = htonl(offset >> 32);
split[1] = htonl(offset & 0xffffffff);
hashwrite(f, split, 8);
nr_large_offset--;
}
}
hashwrite(f, sha1, the_hash_algo->rawsz);
hashclose(f, NULL, ((opts->flags & WRITE_IDX_VERIFY)
? CSUM_CLOSE : CSUM_FSYNC));
return index_name;
}
off_t write_pack_header(struct hashfile *f, uint32_t nr_entries)
{
struct pack_header hdr;
hdr.hdr_signature = htonl(PACK_SIGNATURE);
hdr.hdr_version = htonl(PACK_VERSION);
hdr.hdr_entries = htonl(nr_entries);
hashwrite(f, &hdr, sizeof(hdr));
return sizeof(hdr);
}
void fixup_pack_header_footer(int pack_fd,
unsigned char *new_pack_hash,
const char *pack_name,
uint32_t object_count,
unsigned char *partial_pack_hash,
off_t partial_pack_offset)
{
int aligned_sz, buf_sz = 8 * 1024;
git_hash_ctx old_hash_ctx, new_hash_ctx;
struct pack_header hdr;
char *buf;
ssize_t read_result;
the_hash_algo->init_fn(&old_hash_ctx);
the_hash_algo->init_fn(&new_hash_ctx);
if (lseek(pack_fd, 0, SEEK_SET) != 0)
die_errno("Failed seeking to start of '%s'", pack_name);
read_result = read_in_full(pack_fd, &hdr, sizeof(hdr));
if (read_result < 0)
die_errno("Unable to reread header of '%s'", pack_name);
else if (read_result != sizeof(hdr))
die_errno("Unexpected short read for header of '%s'",
pack_name);
if (lseek(pack_fd, 0, SEEK_SET) != 0)
die_errno("Failed seeking to start of '%s'", pack_name);
the_hash_algo->update_fn(&old_hash_ctx, &hdr, sizeof(hdr));
hdr.hdr_entries = htonl(object_count);
the_hash_algo->update_fn(&new_hash_ctx, &hdr, sizeof(hdr));
write_or_die(pack_fd, &hdr, sizeof(hdr));
partial_pack_offset -= sizeof(hdr);
buf = xmalloc(buf_sz);
aligned_sz = buf_sz - sizeof(hdr);
for (;;) {
ssize_t m, n;
m = (partial_pack_hash && partial_pack_offset < aligned_sz) ?
partial_pack_offset : aligned_sz;
n = xread(pack_fd, buf, m);
if (!n)
break;
if (n < 0)
die_errno("Failed to checksum '%s'", pack_name);
the_hash_algo->update_fn(&new_hash_ctx, buf, n);
aligned_sz -= n;
if (!aligned_sz)
aligned_sz = buf_sz;
if (!partial_pack_hash)
continue;
the_hash_algo->update_fn(&old_hash_ctx, buf, n);
partial_pack_offset -= n;
if (partial_pack_offset == 0) {
unsigned char hash[GIT_MAX_RAWSZ];
the_hash_algo->final_fn(hash, &old_hash_ctx);
if (hashcmp(hash, partial_pack_hash) != 0)
die("Unexpected checksum for %s "
"(disk corruption?)", pack_name);
the_hash_algo->init_fn(&old_hash_ctx);
partial_pack_offset = ~partial_pack_offset;
partial_pack_offset -= MSB(partial_pack_offset, 1);
}
}
free(buf);
if (partial_pack_hash)
the_hash_algo->final_fn(partial_pack_hash, &old_hash_ctx);
the_hash_algo->final_fn(new_pack_hash, &new_hash_ctx);
write_or_die(pack_fd, new_pack_hash, the_hash_algo->rawsz);
fsync_or_die(pack_fd, pack_name);
}
char *index_pack_lockfile(int ip_out)
{
char packname[GIT_MAX_HEXSZ + 6];
const int len = the_hash_algo->hexsz + 6;
if (read_in_full(ip_out, packname, len) == len && packname[len-1] == '\n') {
const char *name;
packname[len-1] = 0;
if (skip_prefix(packname, "keep\t", &name))
return xstrfmt("%s/pack/pack-%s.keep",
get_object_directory(), name);
}
return NULL;
}
int encode_in_pack_object_header(unsigned char *hdr, int hdr_len,
enum object_type type, uintmax_t size)
{
int n = 1;
unsigned char c;
if (type < OBJ_COMMIT || type > OBJ_REF_DELTA)
die("bad type %d", type);
c = (type << 4) | (size & 15);
size >>= 4;
while (size) {
if (n == hdr_len)
die("object size is too enormous to format");
*hdr++ = c | 0x80;
c = size & 0x7f;
size >>= 7;
n++;
}
*hdr = c;
return n;
}
struct hashfile *create_tmp_packfile(char **pack_tmp_name)
{
struct strbuf tmpname = STRBUF_INIT;
int fd;
fd = odb_mkstemp(&tmpname, "pack/tmp_pack_XXXXXX");
*pack_tmp_name = strbuf_detach(&tmpname, NULL);
return hashfd(fd, *pack_tmp_name);
}
void finish_tmp_packfile(struct strbuf *name_buffer,
const char *pack_tmp_name,
struct pack_idx_entry **written_list,
uint32_t nr_written,
struct pack_idx_option *pack_idx_opts,
unsigned char sha1[])
{
const char *idx_tmp_name;
int basename_len = name_buffer->len;
if (adjust_shared_perm(pack_tmp_name))
die_errno("unable to make temporary pack file readable");
idx_tmp_name = write_idx_file(NULL, written_list, nr_written,
pack_idx_opts, sha1);
if (adjust_shared_perm(idx_tmp_name))
die_errno("unable to make temporary index file readable");
strbuf_addf(name_buffer, "%s.pack", sha1_to_hex(sha1));
if (rename(pack_tmp_name, name_buffer->buf))
die_errno("unable to rename temporary pack file");
strbuf_setlen(name_buffer, basename_len);
strbuf_addf(name_buffer, "%s.idx", sha1_to_hex(sha1));
if (rename(idx_tmp_name, name_buffer->buf))
die_errno("unable to rename temporary index file");
strbuf_setlen(name_buffer, basename_len);
free((void *)idx_tmp_name);
}