source->bytes_available -= sizeof(bitreservoir_fill_t);
source->bits |= (bitreservoir_t)fill << (BITRESERVOIR_SIZE - BITRESERVOIR_FILL_SIZE - source->bits_available);
source->bits_available += BITRESERVOIR_FILL_SIZE;
source->bytes_available -= sizeof(bitreservoir_fill_t);
source->bits |= (bitreservoir_t)fill << (BITRESERVOIR_SIZE - BITRESERVOIR_FILL_SIZE - source->bits_available);
source->bits_available += BITRESERVOIR_FILL_SIZE;