Add MIDI controller device index to InputEventMIDI.device property.

It is possible to query the OS for the connected MIDI controllers,
but the event messages' device field was not being used. This implements
controller index being sent in InputEventMIDI messages in the device
property, matching the index from OS.get_connected_midi_inputs().

Based on the work done by @ramdor.

Closes godotengine/godot-proposals#7733

Co-authored-by: Richie <richie_github@grange-lane.co.uk>

4 files changed, 14 insertions, 13 deletions

diff --git a/drivers/alsamidi/midi_driver_alsamidi.cpp b/drivers/alsamidi/midi_driver_alsamidi.cpp
index 6b35987f70..b87be69cc5 100644
--- a/drivers/alsamidi/midi_driver_alsamidi.cpp
+++ b/drivers/alsamidi/midi_driver_alsamidi.cpp
@@ -82,13 +82,13 @@ size_t MIDIDriverALSAMidi::msg_expected_data(uint8_t status_byte) {
 }
 
 void MIDIDriverALSAMidi::InputConnection::parse_byte(uint8_t byte, MIDIDriverALSAMidi &driver,
-		uint64_t timestamp) {
+		uint64_t timestamp, int device_index) {
 	switch (msg_category(byte)) {
 		case MessageCategory::RealTime:
 			// Real-Time messages are single byte messages that can
 			// occur at any point.
 			// We pass them straight through.
-			driver.receive_input_packet(timestamp, &byte, 1);
+			driver.receive_input_packet(device_index, timestamp, &byte, 1);
 			break;
 
 		case MessageCategory::Data:
@@ -100,7 +100,7 @@ void MIDIDriverALSAMidi::InputConnection::parse_byte(uint8_t byte, MIDIDriverALS
 
 				// Forward a complete message and reset relevant state.
 				if (received_data == expected_data) {
-					driver.receive_input_packet(timestamp, buffer, received_data + 1);
+					driver.receive_input_packet(device_index, timestamp, buffer, received_data + 1);
 					received_data = 0;
 
 					if (msg_category(buffer[0]) != MessageCategory::Voice) {
@@ -130,13 +130,13 @@ void MIDIDriverALSAMidi::InputConnection::parse_byte(uint8_t byte, MIDIDriverALS
 			expected_data = msg_expected_data(byte);
 			skipping_sys_ex = false;
 			if (expected_data == 0) {
-				driver.receive_input_packet(timestamp, &byte, 1);
+				driver.receive_input_packet(device_index, timestamp, &byte, 1);
 			}
 			break;
 	}
 }
 
-int MIDIDriverALSAMidi::InputConnection::read_in(MIDIDriverALSAMidi &driver, uint64_t timestamp) {
+int MIDIDriverALSAMidi::InputConnection::read_in(MIDIDriverALSAMidi &driver, uint64_t timestamp, int device_index) {
 	int ret;
 	do {
 		uint8_t byte = 0;
@@ -147,7 +147,7 @@ int MIDIDriverALSAMidi::InputConnection::read_in(MIDIDriverALSAMidi &driver, uin
 				ERR_PRINT("snd_rawmidi_read error: " + String(snd_strerror(ret)));
 			}
 		} else {
-			parse_byte(byte, driver, timestamp);
+			parse_byte(byte, driver, timestamp, device_index);
 		}
 	} while (ret > 0);
 
@@ -165,7 +165,7 @@ void MIDIDriverALSAMidi::thread_func(void *p_udata) {
 		size_t connection_count = md->connected_inputs.size();
 
 		for (size_t i = 0; i < connection_count; i++) {
-			connections[i].read_in(*md, timestamp);
+			connections[i].read_in(*md, timestamp, (int)i);
 		}
 
 		md->unlock();
diff --git a/drivers/alsamidi/midi_driver_alsamidi.h b/drivers/alsamidi/midi_driver_alsamidi.h
index 80cc96310f..95ded3b1c9 100644
--- a/drivers/alsamidi/midi_driver_alsamidi.h
+++ b/drivers/alsamidi/midi_driver_alsamidi.h
@@ -58,7 +58,7 @@ class MIDIDriverALSAMidi : public MIDIDriver {
 				rawmidi_ptr{ midi_in } {}
 
 		// Read in and parse available data, forwarding any complete messages through the driver.
-		int read_in(MIDIDriverALSAMidi &driver, uint64_t timestamp);
+		int read_in(MIDIDriverALSAMidi &driver, uint64_t timestamp, int device_index);
 
 		snd_rawmidi_t *rawmidi_ptr = nullptr;
 
@@ -68,7 +68,7 @@ class MIDIDriverALSAMidi : public MIDIDriver {
 		size_t expected_data = 0;
 		size_t received_data = 0;
 		bool skipping_sys_ex = false;
-		void parse_byte(uint8_t byte, MIDIDriverALSAMidi &driver, uint64_t timestamp);
+		void parse_byte(uint8_t byte, MIDIDriverALSAMidi &driver, uint64_t timestamp, int device_index);
 	};
 
 	Vector<InputConnection> connected_inputs;
diff --git a/drivers/coremidi/midi_driver_coremidi.cpp b/drivers/coremidi/midi_driver_coremidi.cpp
index ed991b3d9d..87fc7612f7 100644
--- a/drivers/coremidi/midi_driver_coremidi.cpp
+++ b/drivers/coremidi/midi_driver_coremidi.cpp
@@ -39,8 +39,9 @@
 
 void MIDIDriverCoreMidi::read(const MIDIPacketList *packet_list, void *read_proc_ref_con, void *src_conn_ref_con) {
 	MIDIPacket *packet = const_cast<MIDIPacket *>(packet_list->packet);
+	int *device_index = static_cast<int *>(src_conn_ref_con);
 	for (UInt32 i = 0; i < packet_list->numPackets; i++) {
-		receive_input_packet(packet->timeStamp, packet->data, packet->length);
+		receive_input_packet(*device_index, packet->timeStamp, packet->data, packet->length);
 		packet = MIDIPacketNext(packet);
 	}
 }
@@ -64,7 +65,7 @@ Error MIDIDriverCoreMidi::open() {
 	for (int i = 0; i < sources; i++) {
 		MIDIEndpointRef source = MIDIGetSource(i);
 		if (source) {
-			MIDIPortConnectSource(port_in, source, (void *)this);
+			MIDIPortConnectSource(port_in, source, static_cast<void *>(&i));
 			connected_sources.insert(i, source);
 		}
 	}
diff --git a/drivers/winmidi/midi_driver_winmidi.cpp b/drivers/winmidi/midi_driver_winmidi.cpp
index cdbab489c4..07f0226c5d 100644
--- a/drivers/winmidi/midi_driver_winmidi.cpp
+++ b/drivers/winmidi/midi_driver_winmidi.cpp
@@ -36,7 +36,7 @@
 
 void MIDIDriverWinMidi::read(HMIDIIN hMidiIn, UINT wMsg, DWORD_PTR dwInstance, DWORD_PTR dwParam1, DWORD_PTR dwParam2) {
 	if (wMsg == MIM_DATA) {
-		receive_input_packet((uint64_t)dwParam2, (uint8_t *)&dwParam1, 3);
+		receive_input_packet((int)dwInstance, (uint64_t)dwParam2, (uint8_t *)&dwParam1, 3);
 	}
 }
 
@@ -44,7 +44,7 @@ Error MIDIDriverWinMidi::open() {
 	for (UINT i = 0; i < midiInGetNumDevs(); i++) {
 		HMIDIIN midi_in;
 
-		MMRESULT res = midiInOpen(&midi_in, i, (DWORD_PTR)read, (DWORD_PTR)this, CALLBACK_FUNCTION);
+		MMRESULT res = midiInOpen(&midi_in, i, (DWORD_PTR)read, (DWORD_PTR)i, CALLBACK_FUNCTION);
 		if (res == MMSYSERR_NOERROR) {
 			midiInStart(midi_in);
 			connected_sources.insert(i, midi_in);