midway snapshot of work done on managing Region & Source lifetimes correctly. may...

[ardour.git] / libs / pbd / pbd / stateful.h

diff --git a/libs/pbd/pbd/stateful.h b/libs/pbd/pbd/stateful.h
index 78b9eb7b3b4057e897cfb9d743ef156ba399285f..1272a735f93d7487650ecf46795ff71a78dcc555 100644 (file)
--- a/libs/pbd/pbd/stateful.h
+++ b/libs/pbd/pbd/stateful.h
@@ -48,10 +48,7 @@ class Stateful {
 
        virtual XMLNode& get_state (void) = 0;
        virtual int set_state (const XMLNode&, int version) = 0;
-       /* derived types do not have to implement this, but probably should
-          give it serious attention.
-       */
-       virtual bool set_property (const PropertyBase&) { return false; }
+       virtual bool set_property (const PropertyBase&);
 
        PropertyChange set_properties (const PropertyList&);
         const OwnedPropertyList& properties() const { return *_properties; }
@@ -70,7 +67,9 @@ class Stateful {
         /* history management */
 
        void clear_history ();
-        void diff (PropertyList&, PropertyList&) const;
+        void diff (PropertyList&, PropertyList&, Command*) const;
+        bool changed() const;
+
         /* create a property list from an XMLNode
          */
         virtual PropertyList* property_factory(const XMLNode&) const { return 0; }
@@ -82,6 +81,12 @@ class Stateful {
        static int current_state_version;
        static int loading_state_version;
 
+       virtual void suspend_property_changes ();
+       virtual void resume_property_changes ();
+
+       void unlock_property_changes () { _no_property_changes = false; }
+       void block_property_changes () { _no_property_changes = true; }
+       
   protected:
 
        void add_instant_xml (XMLNode&, const sys::path& directory_path);
@@ -100,10 +105,21 @@ class Stateful {
 
        XMLNode *_extra_xml;
        XMLNode *_instant_xml;
-       PBD::ID _id;
+       PBD::ID  _id;
+        int32_t  _frozen;
+        bool     _no_property_changes;
+       PBD::PropertyChange     _pending_changed;
+        Glib::Mutex _lock;
 
        std::string _xml_node_name; ///< name of node to use for this object in XML
        OwnedPropertyList* _properties;
+
+        virtual void send_change (const PropertyChange&);
+        /** derived classes can implement this in order to process a property change
+            within thaw() just before send_change() is called.
+        */
+        virtual void mid_thaw (const PropertyChange&) { }
+        bool property_changes_suspended() const { return g_atomic_int_get (&_frozen) > 0; }
 };
 
 } // namespace PBD