/* Copyright (C) 1999 Masanao Izumo <iz@onicos.co.jp> | |
* Version: 1.0 | |
* LastModified: Dec 25 1999 | |
* This library is free. You can redistribute it and/or modify it. | |
*/ | |
/* | |
* Interfaces: | |
* b64 = base64encode(data); | |
* data = base64decode(b64); | |
*/ | |
(function() { | |
var base64EncodeChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; | |
var base64DecodeChars = new Array( | |
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, | |
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, | |
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63, | |
52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1, | |
-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, | |
15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1, | |
-1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, | |
41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1); | |
function base64encode(str) { | |
var out, i, len; | |
var c1, c2, c3; | |
len = str.length; | |
i = 0; | |
out = ""; | |
while(i < len) { | |
c1 = str.charCodeAt(i++) & 0xff; | |
if(i == len) | |
{ | |
out += base64EncodeChars.charAt(c1 >> 2); | |
out += base64EncodeChars.charAt((c1 & 0x3) << 4); | |
out += "=="; | |
break; | |
} | |
c2 = str.charCodeAt(i++); | |
if(i == len) | |
{ | |
out += base64EncodeChars.charAt(c1 >> 2); | |
out += base64EncodeChars.charAt(((c1 & 0x3)<< 4) | ((c2 & 0xF0) >> 4)); | |
out += base64EncodeChars.charAt((c2 & 0xF) << 2); | |
out += "="; | |
break; | |
} | |
c3 = str.charCodeAt(i++); | |
out += base64EncodeChars.charAt(c1 >> 2); | |
out += base64EncodeChars.charAt(((c1 & 0x3)<< 4) | ((c2 & 0xF0) >> 4)); | |
out += base64EncodeChars.charAt(((c2 & 0xF) << 2) | ((c3 & 0xC0) >>6)); | |
out += base64EncodeChars.charAt(c3 & 0x3F); | |
} | |
return out; | |
} | |
function base64decode(str) { | |
var c1, c2, c3, c4; | |
var i, len, out; | |
len = str.length; | |
i = 0; | |
out = ""; | |
while(i < len) { | |
/* c1 */ | |
do { | |
c1 = base64DecodeChars[str.charCodeAt(i++) & 0xff]; | |
} while(i < len && c1 == -1); | |
if(c1 == -1) | |
break; | |
/* c2 */ | |
do { | |
c2 = base64DecodeChars[str.charCodeAt(i++) & 0xff]; | |
} while(i < len && c2 == -1); | |
if(c2 == -1) | |
break; | |
out += String.fromCharCode((c1 << 2) | ((c2 & 0x30) >> 4)); | |
/* c3 */ | |
do { | |
c3 = str.charCodeAt(i++) & 0xff; | |
if(c3 == 61) | |
return out; | |
c3 = base64DecodeChars[c3]; | |
} while(i < len && c3 == -1); | |
if(c3 == -1) | |
break; | |
out += String.fromCharCode(((c2 & 0XF) << 4) | ((c3 & 0x3C) >> 2)); | |
/* c4 */ | |
do { | |
c4 = str.charCodeAt(i++) & 0xff; | |
if(c4 == 61) | |
return out; | |
c4 = base64DecodeChars[c4]; | |
} while(i < len && c4 == -1); | |
if(c4 == -1) | |
break; | |
out += String.fromCharCode(((c3 & 0x03) << 6) | c4); | |
} | |
return out; | |
} | |
if (!window.btoa) window.btoa = base64encode; | |
if (!window.atob) window.atob = base64decode; | |
})(); |