typedef uint32_t transform_apply_fn(void *st, struct buffer_if *buf,
const char **errmsg);
struct transform_inst_if {
void *st;
transform_setkey_fn *setkey;
typedef uint32_t transform_apply_fn(void *st, struct buffer_if *buf,
const char **errmsg);
struct transform_inst_if {
void *st;
transform_setkey_fn *setkey;