Correctly handle MIDI messages with less than 3 bytes.

include/midi.hpp

@@ -15,33 +15,32 @@ namespace midi {
 
 
 struct Message {
-	uint8_t cmd = 0x00;
-	uint8_t data1 = 0x00;
-	uint8_t data2 = 0x00;
+	uint8_t size = 3;
+	uint8_t bytes[3] = {};
 
 	uint8_t getChannel() {
-		return cmd & 0xf;
+		return bytes[0] & 0xf;
 	}
 	void setChannel(uint8_t channel) {
-		cmd = (cmd & 0xf0) | (channel & 0xf);
+		bytes[0] = (bytes[0] & 0xf0) | (channel & 0xf);
 	}
 	uint8_t getStatus() {
-		return (cmd >> 4) & 0xf;
+		return (bytes[0] >> 4) & 0xf;
 	}
 	void setStatus(uint8_t status) {
-		cmd = (cmd & 0xf) | ((status << 4) & 0xf0);
+		bytes[0] = (bytes[0] & 0xf) | ((status << 4) & 0xf0);
 	}
 	uint8_t getNote() {
-		return data1 & 0x7f;
+		return bytes[1] & 0x7f;
 	}
 	void setNote(uint8_t note) {
-		data1 = note & 0x7f;
+		bytes[1] = note & 0x7f;
 	}
 	uint8_t getValue() {
-		return data2 & 0x7f;
+		return bytes[2] & 0x7f;
 	}
 	void setValue(uint8_t value) {
-		data2 = value & 0x7f;
+		bytes[2] = value & 0x7f;
 	}
 };
 

src/Core/CV_MIDI.cpp

@@ -131,6 +131,7 @@ struct PolyphonicMidiOutput : midi::Output {
 		if (clk) {
 			// Timing clock
 			midi::Message m;
+			m.size = 1;
 			m.setStatus(0xf);
 			m.setChannel(0x8);
 			sendMessage(m);
@@ -168,6 +169,7 @@ struct PolyphonicMidiOutput : midi::Output {
 		if (start) {
 			// Start
 			midi::Message m;
+			m.size = 1;
 			m.setStatus(0xf);
 			m.setChannel(0xa);
 			sendMessage(m);
@@ -181,6 +183,7 @@ struct PolyphonicMidiOutput : midi::Output {
 		if (stop) {
 			// Stop
 			midi::Message m;
+			m.size = 1;
 			m.setStatus(0xf);
 			m.setChannel(0xb);
 			sendMessage(m);
@@ -194,6 +197,7 @@ struct PolyphonicMidiOutput : midi::Output {
 		if (cont) {
 			// Continue
 			midi::Message m;
+			m.size = 1;
 			m.setStatus(0xf);
 			m.setChannel(0xc);
 			sendMessage(m);

src/Core/MIDI_CC.cpp

@@ -82,16 +82,17 @@ struct MIDI_CC : Module {
 
 	void processCC(midi::Message msg) {
 		uint8_t cc = msg.getNote();
+		// Allow CC to be negative if the 8th bit is set.
+		// The gamepad driver abuses this, for example.
+		// Cast uint8_t to int8_t
+		int8_t value = msg.bytes[2];
+		value = clamp(value, -127, 127);
 		// Learn
-		if (learningId >= 0 && values[cc] != msg.data2) {
+		if (learningId >= 0 && values[cc] != value) {
 			learnedCcs[learningId] = cc;
 			learningId = -1;
 		}
-		// Allow CC to be negative if the 8th bit is set.
-		// The gamepad driver abuses this, for example.
-		// Cast uint8_t to int8_t
-		int8_t value = msg.data2;
-		values[cc] = clamp(value, -127, 127);
+		values[cc] = value;
 	}
 
 	json_t *dataToJson() override {

src/gamepad.cpp

@@ -52,7 +52,7 @@ struct InputDevice : midi::InputDevice {
 			msg.setStatus(0xb);
 			msg.setNote(i);
 			// Allow 8th bit to be set
-			msg.data2 = cc;
+			msg.bytes[2] = cc;
 			onMessage(msg);
 		}
 	}

src/keyboard.cpp

@@ -78,10 +78,11 @@ struct InputDevice : midi::InputDevice {
 		if (note > 127)
 			return;
 
+		// MIDI note on
 		midi::Message msg;
-		msg.cmd = 0x9 << 4;
-		msg.data1 = note;
-		msg.data2 = 127;
+		msg.setStatus(0x9);
+		msg.setNote(note);
+		msg.setValue(127);
 		onMessage(msg);
 
 		pressedNotes[key] = note;
@@ -91,10 +92,11 @@ struct InputDevice : midi::InputDevice {
 		auto it = pressedNotes.find(key);
 		if (it != pressedNotes.end()) {
 			int note = it->second;
+			// MIDI note off
 			midi::Message msg;
-			msg.cmd = 0x8 << 4;
-			msg.data1 = note;
-			msg.data2 = 127;
+			msg.setStatus(0x8);
+			msg.setNote(note);
+			msg.setValue(127);
 			onMessage(msg);
 
 			pressedNotes.erase(it);

src/rtmidi.cpp

@@ -30,17 +30,21 @@ struct RtMidiInputDevice : midi::InputDevice {
 	}
 
 	static void midiInputCallback(double timeStamp, std::vector<unsigned char> *message, void *userData) {
-		if (!message) return;
-		if (!userData) return;
+		if (!message)
+			return;
+		if (!userData)
+			return;
 
 		RtMidiInputDevice *midiInputDevice = (RtMidiInputDevice*) userData;
-		if (!midiInputDevice) return;
-		if (message->size() < 3) return;
+		if (!midiInputDevice)
+			return;
 
+		assert(message->size() <= 3);
 		midi::Message msg;
-		msg.cmd = (*message)[0];
-		msg.data1 = (*message)[1];
-		msg.data2 = (*message)[2];
+		msg.size = message->size();
+		for (int i = 0; i < msg.size; i++) {
+			msg.bytes[i] = (*message)[i];
+		}
 		midiInputDevice->onMessage(msg);
 	}
 };
@@ -61,11 +65,7 @@ struct RtMidiOutputDevice : midi::OutputDevice {
 	}
 
 	void sendMessage(midi::Message message) override {
-		unsigned char msg[3];
-		msg[0] = message.cmd;
-		msg[1] = message.data1;
-		msg[2] = message.data2;
-		rtMidiOut->sendMessage(msg, 3);
+		rtMidiOut->sendMessage(message.bytes, message.size);
 	}
 };