code: function _caclAdler32(source,  // @arg Uint8Array - data source
                        adler) { // @arg Integer - initial value
                                 // @ret Uint32 - result
      var MOD_ADLER    = 65521;
      var MAGIC_NUMBER = 5550;
  
      var a =  adler         & 0xffff;
      var b = (adler >>> 16) & 0xffff;
  
      var len = source.length;
      var i = 0;
  
      while (len > 0) {
          var tlen = len > MAGIC_NUMBER ? MAGIC_NUMBER : len;
  
          len -= tlen;
  
          do {
              a += source[i++];
              b += a;
          } while (--tlen);
  
          a %= MOD_ADLER;
          b %= MOD_ADLER;
      }
      return ((b << 16) | a) >>> 0;
  }
docs: GitHub repository URL. http://git.io/Help }@dev --- implements ------------------------------------------