Source: codecString.js

  1. /** @fileOverview Bit array codec implementations.
  2.  *
  3.  * @author Emily Stark
  4.  * @author Mike Hamburg
  5.  * @author Dan Boneh
  6.  */
  7.  
  8. /**
  9.  * UTF-8 strings
  10.  * @namespace
  11.  */
  12. sjcl.codec.utf8String = {
  13.   /** Convert from a bitArray to a UTF-8 string. */
  14.   fromBits: function (arr) {
  15.     var out = "", bl = sjcl.bitArray.bitLength(arr), i, tmp;
  16.     for (i=0; i<bl/8; i++) {
  17.       if ((i&3) === 0) {
  18.         tmp = arr[i/4];
  19.       }
  20.       out += String.fromCharCode(tmp >>> 24);
  21.       tmp <<= 8;
  22.     }
  23.     return decodeURIComponent(escape(out));
  24.   },
  25.   
  26.   /** Convert from a UTF-8 string to a bitArray. */
  27.   toBits: function (str) {
  28.     str = unescape(encodeURIComponent(str));
  29.     var out = [], i, tmp=0;
  30.     for (i=0; i<str.length; i++) {
  31.       tmp = tmp << 8 | str.charCodeAt(i);
  32.       if ((i&3) === 3) {
  33.         out.push(tmp);
  34.         tmp = 0;
  35.       }
  36.     }
  37.     if (i&3) {
  38.       out.push(sjcl.bitArray.partial(8*(i&3), tmp));
  39.     }
  40.     return out;
  41.   }
  42. };