From 5526aa29359a955eccc91527d8875b85eb298860 Mon Sep 17 00:00:00 2001
From: Carl Hetherington <carl@carlh.net>
Date: Tue, 9 Feb 2010 14:44:24 +0000
Subject: [PATCH] Add missing files from previous commit.

git-svn-id: svn://localhost/ardour2/branches/3.0@6665 d708f5d6-7413-0410-9779-e7cbd77b26cf
---
 libs/pbd/pbd/stateful_diff_command.h | 47 +++++++++++++++++++++
 libs/pbd/stateful_diff_command.cc    | 61 ++++++++++++++++++++++++++++
 2 files changed, 108 insertions(+)
 create mode 100644 libs/pbd/pbd/stateful_diff_command.h
 create mode 100644 libs/pbd/stateful_diff_command.cc

diff --git a/libs/pbd/pbd/stateful_diff_command.h b/libs/pbd/pbd/stateful_diff_command.h
new file mode 100644
index 0000000000..b02d7a669e
--- /dev/null
+++ b/libs/pbd/pbd/stateful_diff_command.h
@@ -0,0 +1,47 @@
+/*
+    Copyright (C) 2010 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
+    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,
+    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.
+
+*/
+
+#include "pbd/command.h"
+
+namespace PBD
+{
+
+class Stateful;	
+
+/** A Command which stores its action as the differences between the before and after
+ *  state of a Stateful object.
+ */
+class StatefulDiffCommand : public Command
+{
+public:
+	StatefulDiffCommand (Stateful* s);
+	~StatefulDiffCommand ();
+
+	void operator() ();
+	void undo ();
+
+	XMLNode& get_state ();
+
+private:
+	Stateful* _object; ///< the object in question
+	XMLNode* _before; ///< XML node containing the previous values of XML properties which changed
+	XMLNode* _after; ///< XML node containing the new values of XML properties which changed
+};
+
+};
diff --git a/libs/pbd/stateful_diff_command.cc b/libs/pbd/stateful_diff_command.cc
new file mode 100644
index 0000000000..788a5be034
--- /dev/null
+++ b/libs/pbd/stateful_diff_command.cc
@@ -0,0 +1,61 @@
+/*
+    Copyright (C) 2010 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
+    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,
+    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.
+
+*/
+
+#include "pbd/stateful_diff_command.h"
+
+using namespace std;
+using namespace PBD;
+
+/** Create a new StatefulDiffCommand by examining the changes made to a Stateful
+ *  since the last time that clear_history was called on it.
+ *  @param s Stateful object.
+ */
+
+StatefulDiffCommand::StatefulDiffCommand (Stateful* s)
+	: _object (s)
+{
+	pair<XMLNode *, XMLNode*> const p = s->diff ();
+	_before = p.first;
+	_after = p.second;
+}
+
+
+StatefulDiffCommand::~StatefulDiffCommand ()
+{
+	delete _before;
+	delete _after;
+}
+
+void
+StatefulDiffCommand::operator() ()
+{
+	_object->set_state (*_after, Stateful::current_state_version);
+}
+
+void
+StatefulDiffCommand::undo ()
+{
+	_object->set_state (*_before, Stateful::current_state_version);
+}
+
+XMLNode&
+StatefulDiffCommand::get_state ()
+{
+	/* XXX */
+}