MIDI tracks: split immediate events into ardour- and user-generated

This now allows the already-apparently possible recording of user-input from the kbd
in the MIDI track header to actually be successful

libs/ardour/ardour/midi_track.h

@@ -75,6 +75,7 @@ public:
 
 	void midi_panic(void);
 	bool write_immediate_event (Evoral::EventType event_type, size_t size, const uint8_t* buf);
+	bool write_user_immediate_event (Evoral::EventType event_type, size_t size, const uint8_t* buf);
 
 	std::shared_ptr<VelocityControl> velocity_control() const { return _velocity_control; }
 
@@ -135,7 +136,9 @@ public:
 	MonitorState get_input_monitoring_state (bool recording, bool talkback) const;
 
 	MidiBuffer const& immediate_event_buffer () const { return _immediate_event_buffer; }
+	MidiBuffer const& user_immediate_event_buffer () const { return _user_immediate_event_buffer; }
 	MidiRingBuffer<samplepos_t>& immediate_events () { return _immediate_events; }
+	MidiRingBuffer<samplepos_t>& user_immediate_events () { return _user_immediate_events; }
 
 	void set_input_active (bool);
 	bool input_active () const;
@@ -160,7 +163,9 @@ protected:
 
 private:
 	MidiRingBuffer<samplepos_t> _immediate_events;
+	MidiRingBuffer<samplepos_t> _user_immediate_events;
 	MidiBuffer                  _immediate_event_buffer;
+	MidiBuffer                  _user_immediate_event_buffer;
 	MidiRingBuffer<samplepos_t> _step_edit_ring_buffer;
 	NoteMode                    _note_mode;
 	bool                        _step_editing;

libs/ardour/disk_writer.cc

@@ -572,8 +572,8 @@ DiskWriter::run (BufferSet& bufs, samplepos_t start_sample, samplepos_t end_samp
 		/* AUDIO */
 
 		const size_t n_buffers = bufs.count().n_audio();
-
 		uint32_t n = 0;
+
 		for (auto const& chaninfo : *c) {
 			AudioBuffer& buf (bufs.get_audio (n%n_buffers));
 			++n;
@@ -611,6 +611,8 @@ DiskWriter::run (BufferSet& bufs, samplepos_t start_sample, samplepos_t end_samp
 
 		/* MIDI */
 
+		uint32_t cnt = 0;
+
 		if (_midi_buf) {
 
 			// Pump entire port buffer into the ring buffer (TODO: split cycles?)
@@ -658,7 +660,10 @@ DiskWriter::run (BufferSet& bufs, samplepos_t start_sample, samplepos_t end_samp
 
 				bool skip_event = false;
 				if (mt) {
-					/* skip injected immediate/out-of-band events */
+					/* skip injected immediate/out-of-band
+					 * events, but allow those from
+					 * user_immediate_event_buffer
+					 */
 					MidiBuffer const& ieb (mt->immediate_event_buffer());
 					for (MidiBuffer::const_iterator j = ieb.begin(); j != ieb.end(); ++j) {
 						if (*j == ev) {
@@ -672,6 +677,7 @@ DiskWriter::run (BufferSet& bufs, samplepos_t start_sample, samplepos_t end_samp
 
 				if (!filter || !filter->filter(ev.buffer(), ev.size())) {
 					_midi_buf->write (event_time, ev.event_type(), ev.size(), ev.buffer());
+					cnt++;
 				}
 			}
 
@@ -697,6 +703,9 @@ DiskWriter::run (BufferSet& bufs, samplepos_t start_sample, samplepos_t end_samp
 					}
 				}
 
+			}
+
+			if (cnt) {
 				DataRecorded (_midi_write_source); /* EMIT SIGNAL */
 			}
 		}

libs/ardour/midi_track.cc

@@ -82,7 +82,9 @@ using namespace PBD;
 MidiTrack::MidiTrack (Session& sess, string name, TrackMode mode)
 	: Track (sess, name, PresentationInfo::MidiTrack, mode, DataType::MIDI)
 	, _immediate_events(6096) // FIXME: size?
+	, _user_immediate_events(2048) // FIXME: size?
 	, _immediate_event_buffer(6096)
+	, _user_immediate_event_buffer(2048)
 	, _step_edit_ring_buffer(64) // FIXME: size?
 	, _note_mode (Sustained)
 	, _step_editing (false)
@@ -502,7 +504,7 @@ MidiTrack::snapshot_out_of_band_data (samplecnt_t nframes)
 {
 	_immediate_event_buffer.clear ();
 	if (0 == _immediate_events.read_space()) {
-		return;
+		goto user;
 	}
 
 	assert (nframes > 0);
@@ -519,6 +521,28 @@ MidiTrack::snapshot_out_of_band_data (samplecnt_t nframes)
 	 */
 
 	_immediate_events.read (_immediate_event_buffer, 0, 1, nframes - 1, true);
+
+  user:
+	_user_immediate_event_buffer.clear ();
+	if (0 == _user_immediate_events.read_space()) {
+		return;
+	}
+
+	assert (nframes > 0);
+
+	DEBUG_TRACE (DEBUG::MidiIO, string_compose ("%1 has %2 of user immediate events to deliver\n", name(), _user_immediate_events.read_space()));
+
+	/* write as many of the user immediate events as we can, but give "true" as
+	 * the last argument ("stop on overflow in destination") so that we'll
+	 * ship the rest out next time.
+	 *
+	 * the (nframes-1) argument puts all these events at the last
+	 * possible position of the output buffer, so that we do not
+	 * violate monotonicity when writing.
+	 */
+
+	_user_immediate_events.read (_user_immediate_event_buffer, 0, 1, nframes - 1, true);
+
 }
 
 void
@@ -526,6 +550,7 @@ MidiTrack::write_out_of_band_data (BufferSet& bufs, samplecnt_t nframes) const
 {
 	MidiBuffer& buf (bufs.get_midi (0));
 	buf.merge_from (_immediate_event_buffer, nframes);
+	buf.merge_from (_user_immediate_event_buffer, nframes);
 }
 
 int
@@ -650,6 +675,16 @@ MidiTrack::write_immediate_event(Evoral::EventType event_type, size_t size, cons
 	return (_immediate_events.write (0, event_type, size, buf) == size);
 }
 
+bool
+MidiTrack::write_user_immediate_event(Evoral::EventType event_type, size_t size, const uint8_t* buf)
+{
+	if (!Evoral::midi_event_is_valid(buf, size)) {
+		cerr << "WARNING: Ignoring illegal immediate MIDI event" << endl;
+		return false;
+	}
+	return (_user_immediate_events.write (0, event_type, size, buf) == size);
+}
+
 void
 MidiTrack::set_parameter_automation_state (Evoral::Parameter param, AutoState state)
 {
@@ -952,6 +987,7 @@ MidiTrack::realtime_handle_transport_stopped ()
 {
 	Route::realtime_handle_transport_stopped ();
 	_disk_reader->resolve_tracker (_immediate_events, 0);
+	_disk_reader->resolve_tracker (_user_immediate_events, 0);
 }
 
 void