X-Git-Url: https://main.carlh.net/gitweb/?a=blobdiff_plain;f=src%2Flib%2Fcontent_part.h;h=eb96b13710e210593ca47c8911225362d5bfb084;hb=4b7185e4eda53534c4d71a1f31ba33ca3dd8dc8d;hp=2d0f73f7f87096c76e3cb8bf381a7ea3160fca4d;hpb=78664f8073256de51355c9162f61a4ae4fa560d7;p=dcpomatic.git

diff --git a/src/lib/content_part.h b/src/lib/content_part.h
index 2d0f73f7f..eb96b1371 100644
--- a/src/lib/content_part.h
+++ b/src/lib/content_part.h
@@ -1,23 +1,31 @@
+
 /*
     Copyright (C) 2016 Carl Hetherington <cth@carlh.net>
 
-    This program is free software; you can redistribute it and/or modify
+    This file is part of DCP-o-matic.
+
+    DCP-o-matic is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation; either version 2 of the License, or
     (at your option) any later version.
 
-    This program is distributed in the hope that it will be useful,
+    DCP-o-matic is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.
 
     You should have received a copy of the GNU General Public License
-    along with this program; if not, write to the Free Software
-    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+    along with DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.
 
 */
 
+#ifndef DCPOMATIC_CONTENT_PART_H
+#define DCPOMATIC_CONTENT_PART_H
+
+#include "content.h"
+#include "change_signaller.h"
 #include <boost/weak_ptr.hpp>
+#include <boost/thread/mutex.hpp>
 
 class Content;
 class Film;
@@ -25,13 +33,43 @@ class Film;
 class ContentPart
 {
 public:
-	ContentPart (Content* parent, boost::shared_ptr<const Film> film)
+	explicit ContentPart (Content* parent)
 		: _parent (parent)
-		, _film (film)
 	{}
 
 protected:
+	template <class T>
+	void
+	maybe_set (T& member, T new_value, int property) const
+	{
+		ChangeSignaller<Content> cc (_parent, property);
+		{
+			boost::mutex::scoped_lock lm (_mutex);
+			if (member == new_value) {
+				cc.abort ();
+				return;
+			}
+			member = new_value;
+		}
+	}
+
+	template <class T>
+	void
+	maybe_set (boost::optional<T>& member, T new_value, int property) const
+	{
+		ChangeSignaller<Content> cc (_parent, property);
+		{
+			boost::mutex::scoped_lock lm (_mutex);
+			if (member && member.get() == new_value) {
+				cc.abort ();
+				return;
+			}
+			member = new_value;
+		}
+	}
+
 	Content* _parent;
-	boost::weak_ptr<const Film> _film;
 	mutable boost::mutex _mutex;
 };
+
+#endif