Fix LTC encoder removal

Fixed a crash if an x-run or graph-reorder happens after the LTC encoder
has been destroyed (possible at session-close or after disabling
the encoder).  This also fixes duplicate callbacks in case the
encoder was re-enabled times in an active session.

2 files changed, 6 insertions, 2 deletions

diff --git a/libs/ardour/ardour/session.h b/libs/ardour/ardour/session.h
index 96adcf0981..1123abd02e 100644
--- a/libs/ardour/ardour/session.h
+++ b/libs/ardour/ardour/session.h
@@ -1677,6 +1677,8 @@ class LIBARDOUR_API Session : public PBD::StatefulDestructible, public PBD::Scop
 	void ltc_tx_recalculate_position();
 	void ltc_tx_parse_offset();
 	void ltc_tx_send_time_code_for_cycle (framepos_t, framepos_t, double, double, pframes_t nframes);
+	PBD::ScopedConnectionList ltc_tx_connections;
+
 
 	void reset_record_status ();
 
diff --git a/libs/ardour/session_ltc.cc b/libs/ardour/session_ltc.cc
index 51a39d0677..87fd47e70e 100644
--- a/libs/ardour/session_ltc.cc
+++ b/libs/ardour/session_ltc.cc
@@ -84,8 +84,8 @@ Session::ltc_tx_initialize()
 	ltc_prev_cycle = -1;
 	ltc_tx_reset();
 	ltc_tx_resync_latency();
-	Xrun.connect_same_thread (*this, boost::bind (&Session::ltc_tx_reset, this));
-	engine().GraphReordered.connect_same_thread (*this, boost::bind (&Session::ltc_tx_resync_latency, this));
+	Xrun.connect_same_thread (ltc_tx_connections, boost::bind (&Session::ltc_tx_reset, this));
+	engine().GraphReordered.connect_same_thread (ltc_tx_connections, boost::bind (&Session::ltc_tx_resync_latency, this));
 	restarting = false;
 }
 
@@ -97,6 +97,7 @@ Session::ltc_tx_cleanup()
 	ltc_enc_buf = NULL;
 	ltc_encoder_free(ltc_encoder);
 	ltc_encoder = NULL;
+	ltc_tx_connections.drop_connections ();
 }
 
 void
@@ -115,6 +116,7 @@ void
 Session::ltc_tx_reset()
 {
 	DEBUG_TRACE (DEBUG::LTC, "LTC TX reset\n");
+	assert (ltc_encoder);
 	ltc_enc_pos = -9999; // force re-start
 	ltc_buf_len = 0;
 	ltc_buf_off = 0;