ALTER FUNCTION "DBA"."HEXTOUINT"(in s char( 8 ))
RETURNS unsigned int
DETERMINISTIC
BEGIN
    DECLARE "ret" unsigned int;
    DECLARE i int;
    set i=HEXTOINT(s);
    if i< 0  then
        set ret=0xFFFFFFFF + i +  1 ;
    else
        set ret=i;
    end if;
    RETURN "ret";
END

ALTER FUNCTION "DBA"."CRC32"(in b long binary)
RETURNS unsigned integer
DETERMINISTIC
BEGIN
    DECLARE fcs unsigned integer;
    DECLARE i unsigned integer;
    DECLARE s unsigned integer;
    DECLARE n unsigned integer;
    DECLARE k unsigned integer;
    declare fcstab char( 2048 );

    set fcstab='';
    set n= 0 ;
    while n< 256  loop
        set s = n;
        set k= 0 ;
        while k< 8  loop
            if s& 1 = 1  then
                set s=0xedb88320 ^ (s/ 2 );
            else
                set s=s/ 2 ;
            end if;
            set k=k+ 1 ;
        end loop;
        set fcstab = fcstab || right(INTTOHEX(s), 8 );
        set n=n+ 1 ;
    end loop;

    set s=length(b);

    set fcs= 0  ^ 0xFFFFFFFF;
    set i= 0 ;
    while i<s loop
      set fcs = (fcs / 256 ) ^ HEXTOUINT( substr(fcstab, 1 + 8 *((fcs ^ ascii(substr(b,i+ 1 , 1 ))) &  255 ), 8 ) );
      set i = i +  1 ;
    end loop;
    set fcs=fcs ^ 0xFFFFFFFF;
    RETURN "fcs";
END

ALTER FUNCTION "DBA"."GZIP"(in s long varchar)
RETURNS long varchar
DETERMINISTIC
BEGIN
    DECLARE "ret" long varchar;
    declare crc_32 unsigned int;
    declare len unsigned int;
    
    set crc_32=CRC32(s);
    set len=length(s);

    set s=compress(s);
    set s=substr(s, 3 );
    set s=left(s,length(s) -  4 );

    set ret='\x1F\x8B\x08\x00\x00\x00\x00\x00\x00\x0B' || s;
    set ret=ret+char(mod(crc_32, 256 ))+char(mod(crc_32/ 256 , 256 ))+char(mod(crc_32/ 256 / 256 , 256 ))+char(crc_32/ 256 / 256 / 256 );
    set ret=ret+char(mod(len, 256 ))+char(mod(len/ 256 , 256 ))+char(mod(len/ 256 / 256 , 256 ))+char(len/ 256 / 256 / 256 );

    RETURN "ret";
END