20 #include <unistd.h>

    18 #include <csignal>

    21 #include <signal.h>

    22 #include <pthread.h>

    23 #include <sys/mman.h>

    42 static jack_port_t* jackPort = nullptr;

    31 static std::shared_ptr<JackCommand> jackCommand = nullptr;

    43 static jack_ringbuffer_t* ringBuffer = nullptr;

    44 static pthread_mutex_t messageThreadLock = PTHREAD_MUTEX_INITIALIZER;

    45 static pthread_cond_t dataReady = PTHREAD_COND_INITIALIZER;

    47 static bool continueProcessing = true;

    33 void finish(int sig) {

    48 

    34 	if (jackCommand) jackCommand->finish(sig);

    49 const int RING_BUFFER_SIZE = 100;

    50 

    51 struct MidiMessage {

    52 	uint8_t buffer[4096];

    53 	uint32_t size;

    54 	uint32_t time;

    55 };

    56 

    57 int enqueueMessage(jack_nframes_t frames, void* arg) {

    58 	void* buffer = jack_port_get_buffer(jackPort, frames);

    59 	if (buffer == nullptr) throw JackException(L"Unable to get port buffer."); // TODO: exception in RT callback?

    60 

    61 	for (jack_nframes_t i = 0, eventCount = jack_midi_get_event_count(buffer); i < eventCount; i++) {

    62 		jack_midi_event_t event;

    63 		int noData = jack_midi_event_get(&event, buffer, i);

    64 		if (noData) continue;

    65 

    66 		if (event.size > sizeof (MidiMessage::buffer)) {

    67 			// TODO: should not printf in RT callback:

    68 			fwprintf(stderr, L"Error: MIDI message was too large → skipping event. Maximum allowed size: %lu bytes.\n", sizeof (MidiMessage::buffer));

    69 		} else if (jack_ringbuffer_write_space(ringBuffer) >= sizeof (MidiMessage)) {

    70 			MidiMessage m;

    71 			m.time = event.time;

    72 			m.size = event.size;

    73 			memcpy(m.buffer, event.buffer, event.size);

    74 			jack_ringbuffer_write(ringBuffer, (const char *) &m, sizeof (MidiMessage));

    75 		} else {

    76 			// TODO: should not printf in RT callback:

    77 			fwprintf(stderr, L"Error: ring buffer is full → skipping event.\n");

    78 		}

    79 	}

    80 

    81 	// TODO: just count skipped events and bytes and report them in next successful message instead of printing to STDERR

    82 

    83 	if (pthread_mutex_trylock(&messageThreadLock) == 0) {

    84 		pthread_cond_signal(&dataReady);

    85 		pthread_mutex_unlock(&messageThreadLock);

    86 	}

    87 

    88 	return 0;

    89 }

    90 

    91 static void writeRecord(std::shared_ptr<RelationalWriter> writer,

    92 		string_t eventType, integer_t channel,

    93 		boolean_t noteOn, integer_t pitch, integer_t velocity,

    94 		integer_t controllerId, integer_t value) {

    95 	writer->writeAttribute(eventType);

    96 	writer->writeAttribute(&channel, typeid (channel));

    97 	writer->writeAttribute(&noteOn, typeid (noteOn));

    98 	writer->writeAttribute(&pitch, typeid (pitch));

    99 	writer->writeAttribute(&velocity, typeid (velocity));

   100 	writer->writeAttribute(&controllerId, typeid (controllerId));

   101 	writer->writeAttribute(&value, typeid (value));

   102 }

   103 

   104 static void processMessage(std::shared_ptr<RelationalWriter> writer, MidiMessage* event) {

   105 	if (event->size == 0) {

   106 		return;

   107 	} else {

   108 		uint8_t type = event->buffer[0] & 0xF0;

   109 		uint8_t channel = event->buffer[0] & 0x0F;

   110 

   111 		// TODO: write timestamp, message number

   112 		// TODO: write raw buffer in hex

   113 

   114 		if ((type == 0x90 || type == 0x80) && event->size == 3) {

   115 			writeRecord(writer, L"note", channel, type == 0x90, event->buffer[1], event->buffer[2], 0, 0);

   116 		} else if (type == 0xB0 && event->size == 3) {

   117 			writeRecord(writer, L"control", channel, false, 0, 0, event->buffer[1], event->buffer[2]);

   118 		}

   119 	}

   120 }

   121 

   122 static void finish(int sig) {

   123 	continueProcessing = false;

   124 }

   125 

   126 void processJackStream(ostream &output) {

   127 	// Relation headers:

   128 	std::shared_ptr<RelationalWriter> writer(Factory::create(output));

   129 	vector<AttributeMetadata> metadata;

   130 	metadata.push_back({L"event", TypeId::STRING});

   131 	metadata.push_back({L"channel", TypeId::INTEGER});

   132 	metadata.push_back({L"note_on", TypeId::BOOLEAN});

   133 	metadata.push_back({L"note_pitch", TypeId::INTEGER});

   134 	metadata.push_back({L"note_velocity", TypeId::INTEGER});

   135 	metadata.push_back({L"controller_id", TypeId::INTEGER});

   136 	metadata.push_back({L"controller_value", TypeId::INTEGER});

   137 	writer->startRelation(L"midi", metadata, true);

   138 	output.flush();

   139 

   140 	// Initialize JACK connection:

   141 	std::string clientName = "relpipe-in-jack";

   142 	jack_client_t* client = jack_client_open(clientName.c_str(), JackNullOption, nullptr);

   143 	if (client == nullptr) throw JackException(L"Could not create JACK client.");

   144 

   145 	ringBuffer = jack_ringbuffer_create(RING_BUFFER_SIZE * sizeof (MidiMessage));

   146 

   147 	jack_set_process_callback(client, enqueueMessage, nullptr);

   148 	// TODO: report also other events (connections etc.)

   149 

   150 	jackPort = jack_port_register(client, "input", JACK_DEFAULT_MIDI_TYPE, JackPortIsInput, 0);

   151 	if (jackPort == nullptr) throw JackException(L"Could not register port.");

   152 

   153 	if (mlockall(MCL_CURRENT | MCL_FUTURE)) fwprintf(stderr, L"Warning: Can not lock memory.\n");

   154 

   155 	int jackError = jack_activate(client);

   156 	if (jackError) throw JackException(L"Could not activate client.");

   157 

   158 	signal(SIGHUP, finish);

   159 	signal(SIGINT, finish);

   160 

   161 

   162 	// Process messages from the ring buffer queue:

   163 	pthread_mutex_lock(&messageThreadLock);

   164 	while (continueProcessing) {

   165 		const size_t queuedMessages = jack_ringbuffer_read_space(ringBuffer) / sizeof (MidiMessage);

   166 		for (size_t i = 0; i < queuedMessages; ++i) {

   167 			MidiMessage m;

   168 			jack_ringbuffer_read(ringBuffer, (char*) &m, sizeof (MidiMessage));

   169 			processMessage(writer, &m);

   170 			output.flush();

   171 		}

   172 		pthread_cond_wait(&dataReady, &messageThreadLock);

   173 	}

   174 	pthread_mutex_unlock(&messageThreadLock);

   175 

   176 	// Close JACK connection:

   177 	jack_deactivate(client);

   178 	jack_client_close(client);

   179 	jack_ringbuffer_free(ringBuffer);

   192 		processJackStream(cout);

    45 		signal(SIGHUP, finish);

    46 		signal(SIGINT, finish);

    47 		jackCommand.reset(new JackCommand());

    48 		jackCommand->processJackStream(cout);