modified base64

After (v)spprintf i have another modified function here: base64url_(en|de)code I sometimes transmit binary data or thinks like session ids over http. when using base64 the problem is in the chars '+', '/' and '='. So i changed base64 to use '-', '_' and '!' instead. After this change no modification is done to the string as with the '+' sign and i do not have the problems of '=', '/' which would have to be url encoded what makes the string longer. In fact the 65 characters i use now are those 71 characters which have neither a protocol function nor have to be encoded (RFC1321). As these characters have no meaning in filesystems as well things like session ids (len % 4 == 0) which are often used for filenames as well can have shorter names with this encoding. And last but not least these characters have no meaning with regular expressions. In addition i could make the functions accept hexadecimal values as well because (i suppose) in most such cases the input/output is hexadecimal. Reference: RFC1321 MD5, RFC2396 URI, RFC2616 HTTP Any comments? marcus -------->>> mailto:marcus.boerger@post.rwth-aachen.de <<<---------- "Man will never reach the moon, regardless of all future scientific advances" Dr. Lee de Forest, inventor of the Audion tube

                   and father of the radio, Feb. 25, 1967

--------------->>> http://www.marcus-boerger.de <<<----------------