std::unique_ptr<MIDIMappingProto> mapping_proto; // Under <mu>.
int num_controller_banks; // Under <mu>.
std::atomic<int> current_controller_bank{0};
+ std::atomic<int> num_subscribed_ports{0};
std::thread midi_thread;
std::map<unsigned, bool> current_light_status; // Keyed by note number. Under <mu>.