todo ti-websocket-client RFC6455

gistfile1.txt

//
// ti-websocket-client を RFC6455 に対応してみようとする試み。（未完成)
// * 下記を参考にtitanium的に置き換えてみる
// https://github.com/einaros/ws/blob/master/lib/Sender.js
// https://github.com/einaros/ws/blob/master/lib/BufferUtilWindows.js
//

WebSocket.prototype._create_frame = function(opcode, d, last_frame) {
  if(typeof last_frame === 'undefined') {
    last_frame = true;
  }
  
  if(last_frame === false && opcode >= 0x8 && opcode <= 0xf) {
    return false;
  }

  var data = d || '';
  var dataLength = Utils.byte_length(data);
  var dataOffset = 2;
  if(!this._masking_disabled){
    dataOffset = 6;
  }
  var secondByte = dataLength;

  if(BUFFER_SIZE <= dataLength){
    dataOffset += 8;
    secondByte = 127;
  } else if(125 < dataLength){
    dataOffset += 2;
    secondByte = 126;
  }

  var totalLength = 0;
  if(this._masking_disabled){
    totalLength = dataOffset;
  } else {
    totalLength = dataLength + dataOffset;
  }
  var outputBuffer = Ti.createBuffer({ length: totalLength });

  if(last_frame){
    Ti.Codec.encodeNumber({
      source: opcode | 0x80,
      dest: outputBuffer,
      position: 0,
      type: Ti.Codec.TYPE_BYTE
    });
  } else {
    Ti.Codec.encodeNumber({
      source: opcode,
      dest: outputBuffer,
      position: 0,
      type: Ti.Codec.TYPE_BYTE
    });
  }

  if(this._masking_disabled){
    Ti.Codec.encodeNumber({
      source: secondByte,
      dest: outputBuffer,
      position: 1,
      type: Ti.Codec.TYPE_BYTE
    });
  } else {
    Ti.Codec.encodeNumber({
      source: (secondByte | 0x80),
      dest: outputBuffer,
      position: 1,
      type: Ti.Codec.TYPE_BYTE
    });
  }

  switch(secondByte){
  case 126:
    Ti.Codec.encodeNumber({
      source: dataLength,
      dest: outputBuffer,
      position: 2,
      type: Ti.Codec.TYPE_SHORT,
      byteOrder: Ti.Codec.BIG_ENDIAN
    });
    break;
  case 127:
    Ti.Codec.encodeNumber({
      source: 0,
      dest: outputBuffer,
      position: 2,
      type: Ti.Codec.TYPE_BYTE
    });
    Ti.Codec.encodeNumber({
      source: dataLength,
      dest: outputBuffer,
      position: 6,
      type: Ti.Codec.TYPE_LONG,
      byteOrder: Ti.Codec.BIG_ENDIAN
    });
  }

  var getRandomMask = function (){
    var keys = [];
    keys.push(Math.floor(Math.random() * 255) & 0xff);
    keys.push(Math.floor(Math.random() * 255) & 0xff);
    keys.push(Math.floor(Math.random() * 255) & 0xff);
    keys.push(Math.floor(Math.random() * 255) & 0xff);
    return keys;
  };
  var applyMask = function(source, masks, output, offset, length){
    var buffer = Ti.createBuffer({ length: length });
    Ti.Codec.encodeString({
      source: source,
      dest: buffer
    });
    var string = Ti.Codec.decodeString({
      source: buffer,
      charset: Ti.Codec.CHARSET_ASCII
    });

    var maskNum = masks.length;
    var i = 0;
    for(; i < length - 3; i += 4){
      Ti.Codec.encodeNumber({
        source: string.charCodeAt(i) ^ masks[i % maskNum],
        dest: output,
        position: offset + i,
        type: Ti.Codec.TYPE_BYTE
      });
    }
    switch(length % 4){
    case 3:
      Ti.Codec.encodeNumber({
        source: source[i + 2] ^ masks[2],
        dest: output,
        position: offset + i + 2,
        type: Ti.Codec.TYPE_BYTE
      });
    case 2:
      Ti.Codec.encodeNumber({
        source: source[i + 1] ^ masks[1],
        dest: output,
        position: offset + i + 1,
        type: Ti.Codec.TYPE_BYTE
      });
    case 1:
      Ti.Codec.encodeNumber({
        source: source[i] ^ masks[0],
        dest: output,
        position: offset + i,
        type: Ti.Codec.TYPE_BYTE
      });
    case 0:
      break;
    }
  };

  if(!this._masking_disabled){
    var mask = getRandomMask();
    Ti.Codec.encodeNumber({
      source: mask[0],
      dest: outputBuffer,
      position: dataOffset - 4,
      type: Ti.Codec.TYPE_BYTE
    });
    Ti.Codec.encodeNumber({
      source: mask[1],
      dest: outputBuffer,
      position: dataOffset - 3,
      type: Ti.Codec.TYPE_BYTE
    });
    Ti.Codec.encodeNumber({
      source: mask[2],
      dest: outputBuffer,
      position: dataOffset - 2,
      type: Ti.Codec.TYPE_BYTE
    });
    Ti.Codec.encodeNumber({
      source: mask[3],
      dest: outputBuffer,
      position: dataOffset - 1,
      type: Ti.Codec.TYPE_BYTE
    });
    applyMask(data, mask, outputBuffer, dataOffset, dataLength);
  }
  return outputBuffer;
};