void MyClass::sendDataToSocket(const QString &header, const QVariant &data){
   if (! ( state() == QAbstractSocket::UnconnectedState  ) )   {
    QByteArray block;
    QDataStream out(&block, QIODevice::ReadWrite); 
    out.setVersion(QDataStream::Qt_4_1); 
    out << quint16(0);
    out << header;    
    out << data;
    out.device()->seek(0); 
    out << quint16(block.size() - sizeof(quint16)); 
   write(block); 
}//void sendData

void Server::getDataFromSocket(){
  QDataStream in(this);
  QString header;
  QVariant data;
  in.setVersion(QDataStream::Qt_4_1);
  logFile.writeString("[thread] - new data recieved"); 
  forever { 
    if (nextBlockSize == 0) { 
      if (bytesAvailable() < sizeof(quint16)) break; 
      in >> nextBlockSize; 
    } 
    if (bytesAvailable() < nextBlockSize)      break; 
      in >> header;
      in >> data;
      logFile.writeString( "[thread] - received header " + header + data.toString());      
      nextBlockSize = 0; 
  }
}

void Server::getDataFromSocket()
{
  ring_buffer << readAll();
forever
{
  if ( ring_buffer.size() < sizeof(quint16) )
    return;
  QDataStream stream( &ring_buffer );
  quint16 size;
  stream >> size;
  if ( ring_buffer.size() < size + sizeof(quint16) )
    return;
  // read useful data
  stream.close();
  ring_buffer.remove( 0, sizeof(quint16) + size );
}
}