#define RECORD_LAYER_set_read_ahead(rl, ra) ((rl)->read_ahead = (ra))
#define RECORD_LAYER_get_read_ahead(rl) ((rl)->read_ahead)
#define RECORD_LAYER_get_rbuf(rl) (&(rl)->rbuf)
#define RECORD_LAYER_set_read_ahead(rl, ra) ((rl)->read_ahead = (ra))
#define RECORD_LAYER_get_read_ahead(rl) ((rl)->read_ahead)
#define RECORD_LAYER_get_rbuf(rl) (&(rl)->rbuf)