Function serial_data_available

Marlin/src/gcode/queue.cpp:279–288

}

static bool serial_data_available(serial_index_t index) {
  const int a = SERIAL_IMPL.available(index);
  #if ENABLED(RX_BUFFER_MONITOR) && RX_BUFFER_SIZE
    if (a > RX_BUFFER_SIZE - 2) {
      PORT_REDIRECT(SERIAL_PORTMASK(index));
      SERIAL_ERROR_MSG("RX BUF overflow, increase RX_BUFFER_SIZE: ", a);
    }
  #endif
  return a > 0;
}

#if NO_TIMEOUTS > 0
  // Multiserial already handles dispatch to/from multiple ports