From d07ed3b04fc0daecbdb6e3e81cac934fca91358f Mon Sep 17 00:00:00 2001
From: Paul Davis <paul@linuxaudiosystems.com>
Date: Wed, 2 Mar 2016 23:43:42 -0500
Subject: [PATCH] add GainControl::slaved() predicate

---
 libs/ardour/ardour/gain_control.h | 1 +
 libs/ardour/gain_control.cc       | 7 +++++++
 2 files changed, 8 insertions(+)

diff --git a/libs/ardour/ardour/gain_control.h b/libs/ardour/ardour/gain_control.h
index 8dea7a7750..7a4524c34c 100644
--- a/libs/ardour/ardour/gain_control.h
+++ b/libs/ardour/ardour/gain_control.h
@@ -58,6 +58,7 @@ class LIBARDOUR_API GainControl : public AutomationControl {
 	void remove_master (boost::shared_ptr<VCA>);
 	void clear_masters ();
 	bool slaved_to (boost::shared_ptr<VCA>) const;
+	bool slaved () const;
 	std::vector<uint32_t> masters () const;
 
 	PBD::Signal0<void> VCAStatusChange;
diff --git a/libs/ardour/gain_control.cc b/libs/ardour/gain_control.cc
index d655b700b4..29b9146a0a 100644
--- a/libs/ardour/gain_control.cc
+++ b/libs/ardour/gain_control.cc
@@ -227,6 +227,13 @@ GainControl::slaved_to (boost::shared_ptr<VCA> vca) const
 	return find (_masters.begin(), _masters.end(), vca->control()) != _masters.end();
 }
 
+bool
+GainControl::slaved () const
+{
+	Glib::Threads::Mutex::Lock lm (master_lock);
+	return !_masters.empty();
+}
+
 XMLNode&
 GainControl::get_state ()
 {