mime-js

Create MIME message from browser, fork of https://github.com/ikr0m/mime-js
git clone git://git.defalsify.org/mime-js.git
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base64.js (3258B)

      1 var Base64 = {
      2   // private property
      3   _keyStr : "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=",
      4 
      5   // public method for encoding
      6   encode : function (input, needEncoding) {
      7     var output = "";
      8     var chr1, chr2, chr3, enc1, enc2, enc3, enc4;
      9     var i = 0;
     10  
     11     if (needEncoding) {
     12       input = Base64._utf8_encode(input);
     13     }
     14  
     15     while (i < input.length) {
     16       chr1 = input.charCodeAt(i++);
     17       chr2 = input.charCodeAt(i++);
     18       chr3 = input.charCodeAt(i++);
     19  
     20       enc1 = chr1 >> 2;
     21       enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
     22       enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
     23       enc4 = chr3 & 63;
     24  
     25       if (isNaN(chr2)) {
     26         enc3 = enc4 = 64;
     27       } else if (isNaN(chr3)) {
     28         enc4 = 64;
     29       }
     30  
     31       output = output +
     32       this._keyStr.charAt(enc1) + this._keyStr.charAt(enc2) +
     33       this._keyStr.charAt(enc3) + this._keyStr.charAt(enc4);
     34     }
     35  
     36     return output;
     37   },
     38  
     39   // public method for decoding
     40   decode : function (input, needDecoding) {
     41     var output = "";
     42     var chr1, chr2, chr3;
     43     var enc1, enc2, enc3, enc4;
     44     var i = 0;
     45  
     46     input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");
     47  
     48     while (i < input.length) {
     49  
     50       enc1 = this._keyStr.indexOf(input.charAt(i++));
     51       enc2 = this._keyStr.indexOf(input.charAt(i++));
     52       enc3 = this._keyStr.indexOf(input.charAt(i++));
     53       enc4 = this._keyStr.indexOf(input.charAt(i++));
     54  
     55       chr1 = (enc1 << 2) | (enc2 >> 4);
     56       chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
     57       chr3 = ((enc3 & 3) << 6) | enc4;
     58  
     59       output = output + String.fromCharCode(chr1);
     60  
     61       if (enc3 != 64) {
     62         output = output + String.fromCharCode(chr2);
     63       }
     64       if (enc4 != 64) {
     65         output = output + String.fromCharCode(chr3);
     66       }
     67     }
     68     
     69     if (needDecoding) {
     70       output = Base64._utf8_decode(output);
     71     }
     72 
     73     return output;
     74   },
     75  
     76   // private method for UTF-8 encoding
     77   _utf8_encode : function (string) {
     78     string = string.replace(/\r\n/g,"\n");
     79     var utftext = "";
     80     for (var n = 0; n < string.length; n++) {
     81       var c = string.charCodeAt(n);
     82       if (c < 128) {
     83         utftext += String.fromCharCode(c);
     84       }
     85       else if((c > 127) && (c < 2048)) {
     86         utftext += String.fromCharCode((c >> 6) | 192);
     87         utftext += String.fromCharCode((c & 63) | 128);
     88       }
     89       else {
     90         utftext += String.fromCharCode((c >> 12) | 224);
     91         utftext += String.fromCharCode(((c >> 6) & 63) | 128);
     92         utftext += String.fromCharCode((c & 63) | 128);
     93       }
     94     }
     95  
     96     return utftext;
     97   },
     98  
     99   // private method for UTF-8 decoding
    100   _utf8_decode : function (utftext) {
    101     var string = "";
    102     var i = 0;
    103     var c = c1 = c2 = 0;
    104  
    105     while ( i < utftext.length ) {
    106       c = utftext.charCodeAt(i);
    107       if (c < 128) {
    108         string += String.fromCharCode(c);
    109         i++;
    110       }
    111       else if((c > 191) && (c < 224)) {
    112         c2 = utftext.charCodeAt(i+1);
    113         string += String.fromCharCode(((c & 31) << 6) | (c2 & 63));
    114         i += 2;
    115       }
    116       else {
    117         c2 = utftext.charCodeAt(i+1);
    118         c3 = utftext.charCodeAt(i+2);
    119         string += String.fromCharCode(((c & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63));
    120         i += 3;
    121       }
    122     }
    123     return string;
    124   }
    125 };