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