fix delivery of MMC events under split process cycle conditions

5 files changed, 22 insertions, 9 deletions

diff --git a/libs/ardour/ardour/session.h b/libs/ardour/ardour/session.h
index 8621b64578..2c0ac05bda 100644
--- a/libs/ardour/ardour/session.h
+++ b/libs/ardour/ardour/session.h
@@ -48,6 +48,7 @@
 #include "evoral/types.hpp"
 
 #include "midi++/types.h"
+#include "midi++/mmc.h"
 
 #include "timecode/time.h"
 
@@ -1248,6 +1249,7 @@ class LIBARDOUR_API Session : public PBD::StatefulDestructible, public PBD::Scop
 
 	MidiTimeoutList midi_timeouts;
 	bool mmc_step_timeout ();
+	void send_immediate_mmc (MIDI::MachineControlCommand);
 
 	MIDI::byte mtc_msg[16];
 	MIDI::byte mtc_timecode_bits;   /* encoding of SMTPE type for MTC */
diff --git a/libs/ardour/session.cc b/libs/ardour/session.cc
index b0d7a1ce4e..5575f42360 100644
--- a/libs/ardour/session.cc
+++ b/libs/ardour/session.cc
@@ -1380,7 +1380,7 @@ Session::enable_record ()
 		if (g_atomic_int_compare_and_exchange (&_record_status, rs, Recording)) {
 
 			_last_record_location = _transport_frame;
-			_mmc->send (MIDI::MachineControlCommand (MIDI::MachineControl::cmdRecordStrobe));
+			send_immediate_mmc (MIDI::MachineControlCommand (MIDI::MachineControl::cmdRecordStrobe));
 
 			if (Config->get_monitoring_model() == HardwareMonitoring && config.get_auto_input()) {
 				set_track_monitor_input_status (true);
@@ -1401,7 +1401,7 @@ Session::disable_record (bool rt_context, bool force)
 
 		if ((!Config->get_latched_record_enable () && !play_loop) || force) {
 			g_atomic_int_set (&_record_status, Disabled);
-			_mmc->send (MIDI::MachineControlCommand (MIDI::MachineControl::cmdRecordExit));
+			send_immediate_mmc (MIDI::MachineControlCommand (MIDI::MachineControl::cmdRecordExit));
 		} else {
 			if (rs == Recording) {
 				g_atomic_int_set (&_record_status, Enabled);
@@ -1455,7 +1455,7 @@ Session::maybe_enable_record ()
 			enable_record ();
 		}
 	} else {
-		_mmc->send (MIDI::MachineControlCommand (MIDI::MachineControl::cmdRecordPause));
+		send_immediate_mmc (MIDI::MachineControlCommand (MIDI::MachineControl::cmdRecordPause));
 		RecordStateChanged (); /* EMIT SIGNAL */
 	}
 
diff --git a/libs/ardour/session_midi.cc b/libs/ardour/session_midi.cc
index 47c7bd4c40..7becd9c667 100644
--- a/libs/ardour/session_midi.cc
+++ b/libs/ardour/session_midi.cc
@@ -33,6 +33,7 @@
 #include "pbd/error.h"
 #include "pbd/pthread_utils.h"
 #include "pbd/timersub.h"
+#include "pbd/stacktrace.h"
 
 #include "timecode/time.h"
 
@@ -425,7 +426,7 @@ Session::send_full_time_code (framepos_t const t, MIDI::pframes_t nframes)
 	// Send message at offset 0, sent time is for the start of this cycle
 	
 	MidiBuffer& mb (_midi_ports->mtc_output_port()->get_midi_buffer (nframes));
-	mb.push_back (0, sizeof (msg), msg);
+	mb.push_back (Port::port_offset(), sizeof (msg), msg);
 
 	_pframes_since_last_mtc = 0;
 	return 0;
@@ -551,6 +552,16 @@ Session::send_midi_time_code_for_cycle (framepos_t start_frame, framepos_t end_f
  OUTBOUND MMC STUFF
 **********************************************************************/
 
+void
+Session::send_immediate_mmc (MachineControlCommand c)
+{
+	if (AudioEngine::instance()->in_process_thread()) {
+		_mmc->send (c, Port::port_offset());
+	} else {
+		_mmc->send (c, 0);
+	}
+		
+}
 
 bool
 Session::mmc_step_timeout ()
diff --git a/libs/ardour/session_state.cc b/libs/ardour/session_state.cc
index 538c408abb..6560c6004b 100644
--- a/libs/ardour/session_state.cc
+++ b/libs/ardour/session_state.cc
@@ -334,8 +334,8 @@ Session::post_engine_init ()
 	// send_full_time_code (0);
 	_engine.transport_locate (0);
 
-	_mmc->send (MIDI::MachineControlCommand (MIDI::MachineControl::cmdMmcReset));
-	_mmc->send (MIDI::MachineControlCommand (Timecode::Time ()));
+	send_immediate_mmc (MIDI::MachineControlCommand (MIDI::MachineControl::cmdMmcReset));
+	send_immediate_mmc (MIDI::MachineControlCommand (Timecode::Time ()));
 
 	MIDI::Name::MidiPatchManager::instance().set_session (this);
 
diff --git a/libs/ardour/session_transport.cc b/libs/ardour/session_transport.cc
index 6954bd0288..dec3683c19 100644
--- a/libs/ardour/session_transport.cc
+++ b/libs/ardour/session_transport.cc
@@ -656,7 +656,7 @@ Session::non_realtime_stop (bool abort, int on_entry, bool& finished)
 		_send_timecode_update = true;
 		
 		if (!dynamic_cast<MTC_Slave*>(_slave)) {
-			_mmc->send (MIDI::MachineControlCommand (MIDI::MachineControl::cmdStop));
+			send_immediate_mmc (MIDI::MachineControlCommand (MIDI::MachineControl::cmdStop));
 
 			/* This (::non_realtime_stop()) gets called by main
 			   process thread, which will lead to confusion
@@ -1371,7 +1371,7 @@ Session::start_transport ()
 		Timecode::Time time;
 		timecode_time_subframes (_transport_frame, time);
 		if (!dynamic_cast<MTC_Slave*>(_slave)) {
-			_mmc->send (MIDI::MachineControlCommand (MIDI::MachineControl::cmdDeferredPlay));
+			send_immediate_mmc (MIDI::MachineControlCommand (MIDI::MachineControl::cmdDeferredPlay));
 		}
 	}
 
@@ -1759,7 +1759,7 @@ Session::send_mmc_locate (framepos_t t)
 	if (!_engine.freewheeling()) {
 		Timecode::Time time;
 		timecode_time_subframes (t, time);
-		_mmc->send (MIDI::MachineControlCommand (time));
+		send_immediate_mmc (MIDI::MachineControlCommand (time));
 	}
 }