int git_zstream_deflatebuf(git_buf *out, const void *in, size_t in_len)
{
git_zstream zs = GIT_ZSTREAM_INIT;
int error = 0;
if ((error = git_zstream_init(&zs)) < 0)
return error;
if ((error = git_zstream_set_input(&zs, in, in_len)) < 0)
goto done;
while (!git_zstream_done(&zs)) {
size_t step = git_zstream_suggest_output_len(&zs), written;
if ((error = git_buf_grow(out, out->size + step)) < 0)
goto done;
written = out->asize - out->size;
if ((error = git_zstream_get_output(
out->ptr + out->size, &written, &zs)) < 0)
goto done;
out->size += written;
}
/* NULL terminate for consistency if possible */
if (out->size < out->asize)
out->ptr[out->size] = '\0';
done:
git_zstream_free(&zs);
return error;
}
static void loose_backend__readstream_free(git_odb_stream *_stream)
{
loose_readstream *stream = (loose_readstream *)_stream;
git_futils_mmap_free(&stream->map);
git_zstream_free(&stream->zstream);
git__free(stream);
}
static int read_header_loose_standard(
git_rawobj *out, const unsigned char *data, size_t len)
{
git_zstream zs = GIT_ZSTREAM_INIT;
obj_hdr hdr;
unsigned char inflated[MAX_HEADER_LEN];
size_t header_len, inflated_len = sizeof(inflated);
int error;
if ((error = git_zstream_init(&zs, GIT_ZSTREAM_INFLATE)) < 0 ||
(error = git_zstream_set_input(&zs, data, len)) < 0 ||
(error = git_zstream_get_output_chunk(inflated, &inflated_len, &zs)) < 0 ||
(error = parse_header(&hdr, &header_len, inflated, inflated_len)) < 0)
goto done;
out->len = hdr.size;
out->type = hdr.type;
done:
git_zstream_free(&zs);
return error;
}
static int loose_backend__readstream(
git_odb_stream **stream_out,
size_t *len_out,
git_otype *type_out,
git_odb_backend *_backend,
const git_oid *oid)
{
loose_backend *backend;
loose_readstream *stream = NULL;
git_hash_ctx *hash_ctx = NULL;
git_buf object_path = GIT_BUF_INIT;
obj_hdr hdr;
int error = 0;
assert(stream_out && len_out && type_out && _backend && oid);
backend = (loose_backend *)_backend;
*stream_out = NULL;
*len_out = 0;
*type_out = GIT_OBJ_BAD;
if (locate_object(&object_path, backend, oid) < 0) {
error = git_odb__error_notfound("no matching loose object",
oid, GIT_OID_HEXSZ);
goto done;
}
stream = git__calloc(1, sizeof(loose_readstream));
GITERR_CHECK_ALLOC(stream);
hash_ctx = git__malloc(sizeof(git_hash_ctx));
GITERR_CHECK_ALLOC(hash_ctx);
if ((error = git_hash_ctx_init(hash_ctx)) < 0 ||
(error = git_futils_mmap_ro_file(&stream->map, object_path.ptr)) < 0 ||
(error = git_zstream_init(&stream->zstream, GIT_ZSTREAM_INFLATE)) < 0)
goto done;
/* check for a packlike loose object */
if (!is_zlib_compressed_data(stream->map.data, stream->map.len))
error = loose_backend__readstream_packlike(&hdr, stream);
else
error = loose_backend__readstream_standard(&hdr, stream);
if (error < 0)
goto done;
stream->stream.backend = _backend;
stream->stream.hash_ctx = hash_ctx;
stream->stream.read = &loose_backend__readstream_read;
stream->stream.free = &loose_backend__readstream_free;
*stream_out = (git_odb_stream *)stream;
*len_out = hdr.size;
*type_out = hdr.type;
done:
if (error < 0) {
git_futils_mmap_free(&stream->map);
git_zstream_free(&stream->zstream);
git_hash_ctx_cleanup(hash_ctx);
git__free(hash_ctx);
git__free(stream);
}
git_buf_dispose(&object_path);
return error;
}
static int read_loose_standard(git_rawobj *out, git_buf *obj)
{
git_zstream zstream = GIT_ZSTREAM_INIT;
unsigned char head[MAX_HEADER_LEN], *body = NULL;
size_t decompressed, head_len, body_len, alloc_size;
obj_hdr hdr;
int error;
if ((error = git_zstream_init(&zstream, GIT_ZSTREAM_INFLATE)) < 0 ||
(error = git_zstream_set_input(&zstream, git_buf_cstr(obj), git_buf_len(obj))) < 0)
goto done;
decompressed = sizeof(head);
/*
* inflate the initial part of the compressed buffer in order to
* parse the header; read the largest header possible, then push the
* remainder into the body buffer.
*/
if ((error = git_zstream_get_output(head, &decompressed, &zstream)) < 0 ||
(error = parse_header(&hdr, &head_len, head, decompressed)) < 0)
goto done;
if (!git_object_typeisloose(hdr.type)) {
giterr_set(GITERR_ODB, "failed to inflate disk object");
error = -1;
goto done;
}
/*
* allocate a buffer and inflate the object data into it
* (including the initial sequence in the head buffer).
*/
if (GIT_ADD_SIZET_OVERFLOW(&alloc_size, hdr.size, 1) ||
(body = git__malloc(alloc_size)) == NULL) {
error = -1;
goto done;
}
assert(decompressed >= head_len);
body_len = decompressed - head_len;
if (body_len)
memcpy(body, head + head_len, body_len);
decompressed = hdr.size - body_len;
if ((error = git_zstream_get_output(body + body_len, &decompressed, &zstream)) < 0)
goto done;
if (!git_zstream_done(&zstream)) {
giterr_set(GITERR_ZLIB, "failed to finish zlib inflation: stream aborted prematurely");
error = -1;
goto done;
}
body[hdr.size] = '\0';
out->data = body;
out->len = hdr.size;
out->type = hdr.type;
done:
if (error < 0)
git__free(body);
git_zstream_free(&zstream);
return error;
}
