void dev_poll_reactor::start_op()

in demo_example/asio/asio/detail/impl/dev_poll_reactor.ipp [151:196]

• 43 lines of code
• 14 McCabe index (conditional complexity)

void dev_poll_reactor::start_op(int op_type, socket_type descriptor,
    dev_poll_reactor::per_descriptor_data&, reactor_op* op,
    bool is_continuation, bool allow_speculative)
{
  asio::detail::mutex::scoped_lock lock(mutex_);

  if (shutdown_)
  {
    post_immediate_completion(op, is_continuation);
    return;
  }

  if (allow_speculative)
  {
    if (op_type != read_op || !op_queue_[except_op].has_operation(descriptor))
    {
      if (!op_queue_[op_type].has_operation(descriptor))
      {
        if (op->perform())
        {
          lock.unlock();
          scheduler_.post_immediate_completion(op, is_continuation);
          return;
        }
      }
    }
  }

  bool first = op_queue_[op_type].enqueue_operation(descriptor, op);
  scheduler_.work_started();
  if (first)
  {
    ::pollfd& ev = add_pending_event_change(descriptor);
    ev.events = POLLERR | POLLHUP;
    if (op_type == read_op
        || op_queue_[read_op].has_operation(descriptor))
      ev.events |= POLLIN;
    if (op_type == write_op
        || op_queue_[write_op].has_operation(descriptor))
      ev.events |= POLLOUT;
    if (op_type == except_op
        || op_queue_[except_op].has_operation(descriptor))
      ev.events |= POLLPRI;
    interrupter_.interrupt();
  }
}