From 9f3181b9c7189fb8fc1657e514ba6f95faa6ab0d Mon Sep 17 00:00:00 2001
From: Jonathan Moore Liles <j.liles@unix.net>
Date: Sun, 13 Dec 2020 14:46:46 -0800
Subject: [PATCH] Mixer: Because disconnecting/connecting JACK ports is slow,
 when handling a change of strip auto input setting, avoid disconnecting a
 port and then reconnecting it later.

---
 mixer/src/Mixer_Strip.C | 43 +++++++++++++++++++++++++++++++++++++++++
 mixer/src/Mixer_Strip.H |  1 +
 mixer/src/Module.H      | 14 ++++++++++++++
 3 files changed, 58 insertions(+)

diff --git a/mixer/src/Mixer_Strip.C b/mixer/src/Mixer_Strip.C
index 371672f..998bbcb 100644
--- a/mixer/src/Mixer_Strip.C
+++ b/mixer/src/Mixer_Strip.C
@@ -940,6 +940,9 @@ Mixer_Strip::menu_cb ( Fl_Widget *w, void *v )
 void
 Mixer_Strip::auto_input ( const char *s )
 {
+    /* break old connections */
+    disconnect_auto_inputs(s);
+    
     if ( _auto_input )
         free( _auto_input );
     
@@ -948,6 +951,7 @@ Mixer_Strip::auto_input ( const char *s )
     if ( s )
         _auto_input = strdup( s );
 
+    /* make new connections */
     mixer->auto_connect();
 }
 
@@ -1024,6 +1028,42 @@ Mixer_Strip::has_group_affinity ( void ) const
     return _auto_input && strncmp( _auto_input, "*/", 2 );
 }
 
+void
+Mixer_Strip::disconnect_auto_inputs ( const char *exclude_pattern )
+{
+    if ( chain() )
+    {
+	JACK_Module *m = (JACK_Module*)chain()->module(0);
+	
+	if ( m )
+	{
+	    for ( unsigned int i = 0; i < m->aux_audio_input.size(); ++i )
+	    {
+		Module::Port *p1 = &m->aux_audio_input[i];
+
+		if ( _auto_input && exclude_pattern )
+		{
+		    /* avoid disconnecting a port that we'll immediately be reconnecting */
+		    for ( unsigned int j = 0; j < p1->nconnected(); ++j )
+		    {
+			Module::Port *p2 = p1->connected_port( j );
+
+			if ( !matches_pattern( exclude_pattern, p2 ) )
+			{
+			    p1->disconnect( p2 );
+			    j--; /* keep our place in the iteration */
+			}
+		    }
+		}
+		else
+		{
+		    m->aux_audio_input[i].disconnect();
+		}
+	    }
+	}
+    }
+}
+
 bool
 Mixer_Strip::maybe_auto_connect_output ( Module::Port *p )
 {
@@ -1071,6 +1111,9 @@ Mixer_Strip::maybe_auto_connect_output ( Module::Port *p )
             return false;
         }
 
+	if ( ! m->aux_audio_input[n].connected_to( p ) )
+	    m->aux_audio_input[n].connect_to( p );
+
         m->aux_audio_input[n].connect_to( p );
         
         if ( p->module()->is_default() )
diff --git a/mixer/src/Mixer_Strip.H b/mixer/src/Mixer_Strip.H
index 9c601d8..28c244b 100644
--- a/mixer/src/Mixer_Strip.H
+++ b/mixer/src/Mixer_Strip.H
@@ -161,6 +161,7 @@ public:
 
     void manual_connection ( bool b );
     bool has_group_affinity ( void ) const;
+    void disconnect_auto_inputs ( const char *exclude_pattern );
     void auto_connect_outputs ( void );
     bool maybe_auto_connect_output ( Module::Port *p );
        
diff --git a/mixer/src/Module.H b/mixer/src/Module.H
index fd53593..2b85146 100644
--- a/mixer/src/Module.H
+++ b/mixer/src/Module.H
@@ -264,6 +264,9 @@ public:
                 /* control and external audio ports belong to a graph */
                 return _connected.size() > 0;
         }
+
+	unsigned int nconnected ( void ) const { return _connected.size(); }
+	    
         bool connected_osc ( void ) const;
 
         Port *connected_port ( void ) const
@@ -271,6 +274,17 @@ public:
                 return _connected.size() == 0 ? NULL : _connected.front();                
             }
 
+	Port *connected_port ( int n ) const
+            {
+		int j = 0;
+		for ( std::list<Module::Port*>::const_iterator i = _connected.begin();
+		      i != _connected.end(); ++i, ++j )
+		    if ( j == n )
+			return *i;
+		
+		return NULL;
+            }
+
         void connect_to ( Port *to )
             {
                 if ( _type != Port::AUX_AUDIO )