X-Git-Url: https://git.carlh.net/gitweb/?a=blobdiff_plain;f=libs%2Fpbd%2Fpbd%2Fsignals.h;h=df4c9cef29331c5d3b0477143d932e0c7fc4df8e;hb=d19ec8ba46274bd41c251f81e63503183db15f08;hp=e40b0bd2a47d868f4d74a1329bbcced0a8e35658;hpb=14a86aaccc8eadb2f2c8dc5f7251fb1f9c602f30;p=ardour.git

diff --git a/libs/pbd/pbd/signals.h b/libs/pbd/pbd/signals.h
index e40b0bd2a4..df4c9cef29 100644
--- a/libs/pbd/pbd/signals.h
+++ b/libs/pbd/pbd/signals.h
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2009-2012 Paul Davis 
+    Copyright (C) 2009-2012 Paul Davis
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -20,59 +20,104 @@
 #ifndef __pbd_signals_h__
 #define __pbd_signals_h__
 
+#include <csignal>
+
 #include <list>
-#include <glibmm/thread.h>
+#include <map>
+
+#ifdef nil
+#undef nil
+#endif
+
+#include <glibmm/threads.h>
 
 #include <boost/noncopyable.hpp>
 #include <boost/bind.hpp>
 #include <boost/bind/protect.hpp>
 #include <boost/function.hpp>
-#include <boost/thread/mutex.hpp>
 #include <boost/enable_shared_from_this.hpp>
 #include <boost/optional.hpp>
 
+#include "pbd/libpbd_visibility.h"
 #include "pbd/event_loop.h"
 
+#ifndef NDEBUG
+#define DEBUG_PBD_SIGNAL_CONNECTIONS
+#endif
+
+#ifdef DEBUG_PBD_SIGNAL_CONNECTIONS
+#include "pbd/stacktrace.h"
+#include <iostream>
+#endif
+
 namespace PBD {
 
-class Connection;
+class LIBPBD_API Connection;
 
-class SignalBase
+class LIBPBD_API SignalBase
 {
 public:
+	SignalBase ()
+#ifdef DEBUG_PBD_SIGNAL_CONNECTIONS
+	: _debug_connection (false)
+#endif
+	{}
 	virtual ~SignalBase () {}
 	virtual void disconnect (boost::shared_ptr<Connection>) = 0;
+#ifdef DEBUG_PBD_SIGNAL_CONNECTIONS
+	void set_debug_connection (bool yn) { _debug_connection = yn; }
+#endif
 
 protected:
-	boost::mutex _mutex;
+	mutable Glib::Threads::Mutex _mutex;
+#ifdef DEBUG_PBD_SIGNAL_CONNECTIONS
+	bool _debug_connection;
+#endif
 };
 
-class Connection : public boost::enable_shared_from_this<Connection>
+class LIBPBD_API Connection : public boost::enable_shared_from_this<Connection>
 {
 public:
-	Connection (SignalBase* b) : _signal (b) {}
+	Connection (SignalBase* b, PBD::EventLoop::InvalidationRecord* ir) : _signal (b), _invalidation_record (ir)
+	{
+		if (_invalidation_record) {
+			_invalidation_record->ref ();
+		}
+	}
 
 	void disconnect ()
 	{
-		boost::mutex::scoped_lock lm (_mutex);
+		Glib::Threads::Mutex::Lock lm (_mutex);
 		if (_signal) {
 			_signal->disconnect (shared_from_this ());
-		} 
+			_signal = 0;
+		}
+	}
+
+	void disconnected ()
+	{
+		if (_invalidation_record) {
+			_invalidation_record->unref ();
+		}
 	}
 
 	void signal_going_away ()
 	{
-		boost::mutex::scoped_lock lm (_mutex);
+		Glib::Threads::Mutex::Lock lm (_mutex);
+		if (_invalidation_record) {
+			_invalidation_record->unref ();
+		}
 		_signal = 0;
 	}
 
 private:
-	boost::mutex _mutex;
+        Glib::Threads::Mutex _mutex;
 	SignalBase* _signal;
+	PBD::EventLoop::InvalidationRecord* _invalidation_record;
 };
 
 template<typename R>
-class OptionalLastValue
+class /*LIBPBD_API*/ OptionalLastValue
 {
 public:
 	typedef boost::optional<R> result_type;
@@ -88,10 +133,10 @@ public:
 		return r;
 	}
 };
-	
+
 typedef boost::shared_ptr<Connection> UnscopedConnection;
-	
-class ScopedConnection
+
+class LIBPBD_API ScopedConnection
 {
 public:
 	ScopedConnection () {}
@@ -109,6 +154,11 @@ public:
 
 	ScopedConnection& operator= (UnscopedConnection const & o)
 	{
+		if (_c == o) {
+			return *this;
+		}
+
+		disconnect ();
 		_c = o;
 		return *this;
 	}
@@ -116,13 +166,13 @@ public:
 private:
 	UnscopedConnection _c;
 };
-	
-class ScopedConnectionList  : public boost::noncopyable
+
+class LIBPBD_API ScopedConnectionList  : public boost::noncopyable
 {
   public:
 	ScopedConnectionList();
 	virtual ~ScopedConnectionList ();
-	
+
 	void add_connection (const UnscopedConnection& c);
 	void drop_connections ();
 
@@ -130,30 +180,25 @@ class ScopedConnectionList  : public boost::noncopyable
 	/* this class is not copyable */
 	ScopedConnectionList(const ScopedConnectionList&);
 
-	/* this lock is shared by all instances of a ScopedConnectionList.
-	   We do not want one mutex per list, and since we only need the lock
-	   when adding or dropping connections, which are generally occuring
-	   in object creation and UI operations, the contention on this 
-	   lock is low and not of significant consequence. Even though
-	   boost::signals2 is thread-safe, this additional list of
+	/* Even though our signals code is thread-safe, this additional list of
 	   scoped connections needs to be protected in 2 cases:
 
 	   (1) (unlikely) we make a connection involving a callback on the
-	       same object from 2 threads. (wouldn't that just be appalling 
+	       same object from 2 threads. (wouldn't that just be appalling
 	       programming style?)
-	     
+
 	   (2) where we are dropping connections in one thread and adding
 	       one from another.
 	 */
 
-	static Glib::StaticMutex _lock;
+	Glib::Threads::Mutex _lock;
 
 	typedef std::list<ScopedConnection*> ConnectionList;
 	ConnectionList _list;
 };
 
-#include "pbd/signals_generated.h"	
-	
+#include "pbd/signals_generated.h"
+
 } /* namespace */
 
 #endif /* __pbd_signals_h__ */