-- revip4: return a reversed dotted-quad (JPM)

DELIMITER $$
CREATE FUNCTION revip4 (quad CHAR(15)) RETURNS CHAR(15)
BEGIN
	DECLARE hexip CHAR(15);
	DECLARE invip CHAR(15);
	
	SET hexip = LPAD( HEX(INET_ATON(quad)), 8, '0');
	SET invip = CONCAT(
	               MID(hexip, 7, 2),
	               MID(hexip, 5, 2),
	               MID(hexip, 3, 2),
	               MID(hexip, 1, 2));

	RETURN INET_NTOA(  CONV(invip, 16, 10) );
END $$
DELIMITER ;