fix crash at session close/exit if a midi-control-surface is used

[ardour.git] / libs / ardour / audio_diskstream.cc

diff --git a/libs/ardour/audio_diskstream.cc b/libs/ardour/audio_diskstream.cc
index 0d2c664e4827290e02f527620dd54f12337f19f9..60b21bbc22c1fa5c24a2acc1f9ca96d851a1ae0c 100644 (file)
--- a/libs/ardour/audio_diskstream.cc
+++ b/libs/ardour/audio_diskstream.cc
@@ -148,6 +148,8 @@ AudioDiskstream::free_working_buffers()
 void
 AudioDiskstream::non_realtime_input_change ()
 {
+       bool need_write_sources = false;
+
        {
                Glib::Threads::Mutex::Lock lm (state_lock);
 
@@ -155,6 +157,11 @@ AudioDiskstream::non_realtime_input_change ()
                        return;
                }
 
+               boost::shared_ptr<ChannelList> cr = channels.reader();
+               if (!cr->empty() && !cr->front()->write_source) {
+                       need_write_sources = true;
+               }
+
                if (input_change_pending.type == IOChange::ConfigurationChanged) {
                        RCUWriter<ChannelList> writer (channels);
                        boost::shared_ptr<ChannelList> c = writer.get_copy();
@@ -166,6 +173,8 @@ AudioDiskstream::non_realtime_input_change ()
                        } else if (_io->n_ports().n_audio() < _n_channels.n_audio()) {
                                remove_channel_from (c, _n_channels.n_audio() - _io->n_ports().n_audio());
                        }
+
+                       need_write_sources = true;
                }
 
                if (input_change_pending.type & IOChange::ConnectionsChanged) {
@@ -179,9 +188,9 @@ AudioDiskstream::non_realtime_input_change ()
                /* implicit unlock */
        }
 
-       /* reset capture files */
-
-       reset_write_sources (false);
+       if (need_write_sources) {
+               reset_write_sources (false);
+       }
 
        /* now refill channel buffers */