Use shared port engine MIDI event compare operator

libs/backends/alsa/alsa_audiobackend.h

@@ -50,14 +50,13 @@ namespace ARDOUR {
 
 class AlsaAudioBackend;
 
-class AlsaMidiEvent {
+class AlsaMidiEvent : public BackendMIDIEvent {
 	public:
 		AlsaMidiEvent (const pframes_t timestamp, const uint8_t* data, size_t size);
 		AlsaMidiEvent (const AlsaMidiEvent& other);
 		size_t size () const { return _size; };
 		pframes_t timestamp () const { return _timestamp; };
 		const uint8_t* data () const { return _data; };
-		bool operator< (const AlsaMidiEvent &other) const { return timestamp () < other.timestamp (); };
 	private:
 		size_t _size;
 		pframes_t _timestamp;

libs/backends/coreaudio/coreaudio_backend.h

@@ -45,14 +45,13 @@ namespace ARDOUR {
 
 class CoreAudioBackend;
 
-class CoreMidiEvent {
+class CoreMidiEvent : public BackendMIDIEvent {
   public:
 	CoreMidiEvent (const pframes_t timestamp, const uint8_t* data, size_t size);
 	CoreMidiEvent (const CoreMidiEvent& other);
 	size_t size () const { return _size; };
 	pframes_t timestamp () const { return _timestamp; };
 	const uint8_t* data () const { return _data; };
-	bool operator< (const CoreMidiEvent &other) const { return timestamp () < other.timestamp (); };
   private:
 	size_t _size;
 	pframes_t _timestamp;

libs/backends/dummy/dummy_audiobackend.cc

@@ -1387,7 +1387,7 @@ void DummyAudioPort::midi_to_wavetable (DummyMidiBuffer const * const src, size_
 		// somewhat arbitrary mapping for quick visual feedback
 		float v = -.5f;
 		if ((*it)->size() == 3) {
-			const unsigned char *d = (*it)->const_data();
+			const unsigned char *d = (*it)->data();
 			if ((d[0] & 0xf0) == 0x90) { // note on
 				v = .25f + d[2] / 512.f;
 			}
@@ -1890,9 +1890,9 @@ DummyMidiEvent::DummyMidiEvent (const DummyMidiEvent& other)
 	, _timestamp (other.timestamp ())
 	, _data (0)
 {
-	if (other.size () && other.const_data ()) {
+	if (other.size () && other.data ()) {
 		_data = (uint8_t*) malloc (other.size ());
-		memcpy (_data, other.const_data (), other.size ());
+		memcpy (_data, other.data (), other.size ());
 	}
 };
 

libs/backends/dummy/dummy_audiobackend.h

@@ -52,16 +52,14 @@ namespace DummyMidiData {
 };
 
 
-class DummyMidiEvent {
+class DummyMidiEvent : public BackendMIDIEvent {
 	public:
 		DummyMidiEvent (const pframes_t timestamp, const uint8_t* data, size_t size);
 		DummyMidiEvent (const DummyMidiEvent& other);
 		~DummyMidiEvent ();
 		size_t size () const { return _size; };
 		pframes_t timestamp () const { return _timestamp; };
-		const unsigned char* const_data () const { return _data; };
-		unsigned char* data () { return _data; };
-		bool operator< (const DummyMidiEvent &other) const { return timestamp () < other.timestamp (); };
+		const uint8_t* data () const { return _data; };
 	private:
 		size_t _size;
 		pframes_t _timestamp;

libs/backends/portaudio/portaudio_backend.h

@@ -43,14 +43,13 @@ namespace ARDOUR {
 
 class PortAudioBackend;
 
-class PortMidiEvent {
+class PortMidiEvent : public BackendMIDIEvent {
 	public:
 		PortMidiEvent (const pframes_t timestamp, const uint8_t* data, size_t size);
 		PortMidiEvent (const PortMidiEvent& other);
 		size_t size () const { return _size; };
 		pframes_t timestamp () const { return _timestamp; };
 		const uint8_t* data () const { return _data; };
-		bool operator< (const PortMidiEvent &other) const { return timestamp () < other.timestamp (); };
 	private:
 		size_t _size;
 		pframes_t _timestamp;

libs/backends/pulseaudio/pulseaudio_backend.h

@@ -43,7 +43,7 @@ namespace ARDOUR {
 
 class PulseAudioBackend;
 
-class PulseMidiEvent
+class PulseMidiEvent : public BackendMIDIEvent
 {
 public:
 	PulseMidiEvent (const pframes_t timestamp, const uint8_t* data, size_t size);
@@ -53,7 +53,6 @@ public:
 	pframes_t timestamp () const { return _timestamp; };
 	const uint8_t* data () const { return _data; };
 	const uint8_t* const_data () const { return _data; };
-	bool operator< (const PulseMidiEvent& other) const { return timestamp () < other.timestamp (); };
 
 private:
 	size_t    _size;