The WebSocket Protocol - The Definitive Guide to HTML5 WebSocket - page 54

// discard high 4 bits because this server cannot handle huge lengths
var highBits = buf.readUInt32BE(2);
if (highBits != 0) {
this.close(1009, "");
}
length = buf.readUInt32BE(6);
idx += 8;
}
}
if (buf.length < idx + 4 + length) {
// insufficient data read
return;
}
maskBytes = buf.slice(idx, idx+4);
idx += 4;
var payload = buf.slice(idx, idx+length);
payload = unmask(maskBytes, payload);
this._handleFrame(opcode, payload);
this.buffer = buf.slice(idx+length);
return true;
}
WebSocketConnection.prototype._handleFrame = function(opcode, buffer) {
var payload;
switch (opcode) {
case opcodes.TEXT:
payload = buffer.toString("utf8");
this.emit("data", opcode, payload);
break;
case opcodes.BINARY:
payload = buffer;
this.emit("data", opcode, payload);
break;
case opcodes.PING:
// Respond to pings with pongs
this._doSend(opcodes.PONG, buffer);
break;
case opcodes.PONG:
// Ignore pongs
break;
case opcodes.CLOSE:
// Parse close and reason
var code, reason;
if (buffer.length >= 2) {
code = buffer.readUInt16BE(0);
reason = buffer.toString("utf8",2);