1 /* This Source Code Form is subject to the terms of the Mozilla Public 2 * License, v. 2.0. If a copy of the MPL was not distributed with this 3 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ 4 5 // From: http://hg.mozilla.org/mozilla-central/raw-file/ec10630b1a54/js/src/devtools/jint/sunspider/string-base64.js 6 7 /*jslint white: false */ 8 /*global console */ 9 10 var Base64 = { 11 /* Convert data (an array of integers) to a Base64 string. */ 12 toBase64Table : 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/='.split(''), 13 base64Pad : '=', 14 15 encode: function (data) { 16 "use strict"; 17 var result = ''; 18 var toBase64Table = Base64.toBase64Table; 19 var length = data.length; 20 var lengthpad = (length % 3); 21 // Convert every three bytes to 4 ascii characters. 22 23 for (var i = 0; i < (length - 2); i += 3) { 24 result += toBase64Table[data[i] >> 2]; 25 result += toBase64Table[((data[i] & 0x03) << 4) + (data[i + 1] >> 4)]; 26 result += toBase64Table[((data[i + 1] & 0x0f) << 2) + (data[i + 2] >> 6)]; 27 result += toBase64Table[data[i + 2] & 0x3f]; 28 } 29 30 // Convert the remaining 1 or 2 bytes, pad out to 4 characters. 31 var j = 0; 32 if (lengthpad === 2) { 33 j = length - lengthpad; 34 result += toBase64Table[data[j] >> 2]; 35 result += toBase64Table[((data[j] & 0x03) << 4) + (data[j + 1] >> 4)]; 36 result += toBase64Table[(data[j + 1] & 0x0f) << 2]; 37 result += toBase64Table[64]; 38 } else if (lengthpad === 1) { 39 j = length - lengthpad; 40 result += toBase64Table[data[j] >> 2]; 41 result += toBase64Table[(data[j] & 0x03) << 4]; 42 result += toBase64Table[64]; 43 result += toBase64Table[64]; 44 } 45 46 return result; 47 }, 48 49 /* Convert Base64 data to a string */ 50 /* jshint -W013 */ 51 toBinaryTable : [ 52 -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, 53 -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, 54 -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,62, -1,-1,-1,63, 55 52,53,54,55, 56,57,58,59, 60,61,-1,-1, -1, 0,-1,-1, 56 -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10, 11,12,13,14, 57 15,16,17,18, 19,20,21,22, 23,24,25,-1, -1,-1,-1,-1, 58 -1,26,27,28, 29,30,31,32, 33,34,35,36, 37,38,39,40, 59 41,42,43,44, 45,46,47,48, 49,50,51,-1, -1,-1,-1,-1 60 ], 61 /* jshint +W013 */ 62 63 decode: function (data, offset) { 64 "use strict"; 65 offset = typeof(offset) !== 'undefined' ? offset : 0; 66 var toBinaryTable = Base64.toBinaryTable; 67 var base64Pad = Base64.base64Pad; 68 var result, result_length; 69 var leftbits = 0; // number of bits decoded, but yet to be appended 70 var leftdata = 0; // bits decoded, but yet to be appended 71 var data_length = data.indexOf('=') - offset; 72 73 if (data_length < 0) { data_length = data.length - offset; } 74 75 /* Every four characters is 3 resulting numbers */ 76 result_length = (data_length >> 2) * 3 + Math.floor((data_length % 4) / 1.5); 77 result = new Array(result_length); 78 79 // Convert one by one. 80 for (var idx = 0, i = offset; i < data.length; i++) { 81 var c = toBinaryTable[data.charCodeAt(i) & 0x7f]; 82 var padding = (data.charAt(i) === base64Pad); 83 // Skip illegal characters and whitespace 84 if (c === -1) { 85 console.error("Illegal character code " + data.charCodeAt(i) + " at position " + i); 86 continue; 87 } 88 89 // Collect data into leftdata, update bitcount 90 leftdata = (leftdata << 6) | c; 91 leftbits += 6; 92 93 // If we have 8 or more bits, append 8 bits to the result 94 if (leftbits >= 8) { 95 leftbits -= 8; 96 // Append if not padding. 97 if (!padding) { 98 result[idx++] = (leftdata >> leftbits) & 0xff; 99 } 100 leftdata &= (1 << leftbits) - 1; 101 } 102 } 103 104 // If there are any bits left, the base64 string was corrupted 105 if (leftbits) { 106 err = new Error('Corrupted base64 string'); 107 err.name = 'Base64-Error'; 108 throw err; 109 } 110 111 return result; 112 } 113 }; /* End of Base64 namespace */ 114
