Support multiple readers for MIDI source/model

Fixes the multiple reader issue #6541 properly without resorting to a
linear search kludge.

All the read state has been pulled out into a MidiCursor which the
caller is required to pass.  The playlist keeps cursors for all the
regions it is reading, any number of cursors are allowed at a time.

MidiCursor should probably be made a smarter and more fool-proof
object (and/or possibly merged with some of the other tracker/fixer
stuff) but for now I wanted to keep it simple.

1 files changed, 10 insertions, 12 deletions

diff --git a/libs/ardour/ardour/midi_source.h b/libs/ardour/ardour/midi_source.h
index 4815263739..1ff0a08f71 100644
--- a/libs/ardour/ardour/midi_source.h
+++ b/libs/ardour/ardour/midi_source.h
@@ -36,8 +36,9 @@
 namespace ARDOUR {
 
 class MidiChannelFilter;
-class MidiStateTracker;
+class MidiCursor;
 class MidiModel;
+class MidiStateTracker;
 
 template<typename T> class MidiRingBuffer;
 
@@ -87,18 +88,18 @@ class LIBARDOUR_API MidiSource : virtual public Source, public boost::enable_sha
 	 * \param tracker an optional pointer to MidiStateTracker object, for note on/off tracking.
 	 * \param filtered Parameters whose MIDI messages will not be returned.
 	 */
-
 	virtual framecnt_t midi_read (const Lock&                        lock,
 	                              Evoral::EventSink<framepos_t>&     dst,
 	                              framepos_t                         source_start,
 	                              framepos_t                         start,
 	                              framecnt_t                         cnt,
 	                              Evoral::Range<framepos_t>*         loop_range,
+	                              MidiCursor&                        cursor,
 	                              MidiStateTracker*                  tracker,
 	                              MidiChannelFilter*                 filter,
 	                              const std::set<Evoral::Parameter>& filtered,
-				      const double                       pulse,
-				      const double                       start_beats) const;
+	                              const double                       pulse,
+	                              const double                       start_beats) const;
 
 	/** Write data from a MidiRingBuffer to this source.
 	 *  @param source Source to read from.
@@ -175,10 +176,11 @@ class LIBARDOUR_API MidiSource : virtual public Source, public boost::enable_sha
 
 	/** Reset cached information (like iterators) when things have changed.
 	 * @param lock Source lock, which must be held by caller.
-	 * @param notes If non-NULL, currently active notes are added to this set.
 	 */
-	void invalidate(const Glib::Threads::Mutex::Lock&                       lock,
-	                std::set<Evoral::Sequence<Evoral::Beats>::WeakNotePtr>* notes=NULL);
+	void invalidate(const Glib::Threads::Mutex::Lock& lock);
+
+	/** Thou shalt not emit this directly, use invalidate() instead. */
+	mutable PBD::Signal1<void, bool> Invalidated;
 
 	void set_note_mode(const Glib::Threads::Mutex::Lock& lock, NoteMode mode);
 
@@ -230,11 +232,7 @@ class LIBARDOUR_API MidiSource : virtual public Source, public boost::enable_sha
 	boost::shared_ptr<MidiModel> _model;
 	bool                         _writing;
 
-	mutable Evoral::Sequence<Evoral::Beats>::const_iterator _model_iter;
-	mutable bool                                            _model_iter_valid;
-
-	mutable Evoral::Beats _length_beats;
-	mutable framepos_t    _last_read_end;
+	Evoral::Beats _length_beats;
 
 	/** The total duration of the current capture. */
 	framepos_t _capture_length;