RNGDATA_SIZE
memcpy(rng.data, digest + RNGSTATE_SIZE, RNGDATA_SIZE);
memcpy(rng.data, digest + RNGSTATE_SIZE, RNGDATA_SIZE);
ASSERT(sz <= RNGDATA_SIZE);
if (rng.nused + sz > RNGDATA_SIZE) {
consumed = RNGDATA_SIZE - rng.nused;
uint8_t data[RNGDATA_SIZE];