/** Start calculating a checksum */
void cksum_begin(SBMP_CksumType type, uint32_t *scratch)
{
switch (type) {
#if SBMP_HAS_CRC32
case SBMP_CKSUM_CRC32:
*scratch = crc32_begin();
break;
#endif
case SBMP_CKSUM_XOR:
*scratch = 0;
break;
case SBMP_CKSUM_NONE: // fall-through
default:
;
}
}
static int deflate_to_pack(struct bulk_checkin_state *state,
unsigned char result_sha1[],
int fd, size_t size,
enum object_type type, const char *path,
unsigned flags)
{
off_t seekback, already_hashed_to;
git_SHA_CTX ctx;
unsigned char obuf[16384];
unsigned header_len;
struct sha1file_checkpoint checkpoint;
struct pack_idx_entry *idx = NULL;
seekback = lseek(fd, 0, SEEK_CUR);
if (seekback == (off_t) -1)
return error("cannot find the current offset");
header_len = xsnprintf((char *)obuf, sizeof(obuf), "%s %" PRIuMAX,
typename(type), (uintmax_t)size) + 1;
git_SHA1_Init(&ctx);
git_SHA1_Update(&ctx, obuf, header_len);
/* Note: idx is non-NULL when we are writing */
if ((flags & HASH_WRITE_OBJECT) != 0)
idx = xcalloc(1, sizeof(*idx));
already_hashed_to = 0;
while (1) {
prepare_to_stream(state, flags);
if (idx) {
sha1file_checkpoint(state->f, &checkpoint);
idx->offset = state->offset;
crc32_begin(state->f);
}
if (!stream_to_pack(state, &ctx, &already_hashed_to,
fd, size, type, path, flags))
break;
/*
* Writing this object to the current pack will make
* it too big; we need to truncate it, start a new
* pack, and write into it.
*/
if (!idx)
die("BUG: should not happen");
sha1file_truncate(state->f, &checkpoint);
state->offset = checkpoint.offset;
finish_bulk_checkin(state);
if (lseek(fd, seekback, SEEK_SET) == (off_t) -1)
return error("cannot seek back");
}
git_SHA1_Final(result_sha1, &ctx);
if (!idx)
return 0;
idx->crc32 = crc32_end(state->f);
if (already_written(state, result_sha1)) {
sha1file_truncate(state->f, &checkpoint);
state->offset = checkpoint.offset;
free(idx);
} else {
hashcpy(idx->oid.hash, result_sha1);
ALLOC_GROW(state->written,
state->nr_written + 1,
state->alloc_written);
state->written[state->nr_written++] = idx;
}
return 0;
}
