Custom Interfaces: Implement derived interface properties in present.

	* glib/glibmm/class.cc (Class::properties_quark): Initialize this
	GQuark which is used to store/get the data used for setting and
	getting the properties of the interfaces that a custom type overrides.
	(Class::interface_finalize_function): Add this function which
	once invoked frees the property data stored as gqata in the GType and
	allocated/appended to in the Glib::Interface constructor below.
	* glib/glibmm/class.h: Declare the interface_finalize_function above.
	Also declare the quark used to store/get the property data and the
	typedef data type of the property data.

	* glib/glibmm/interface.cc (Interface_Class::add_interface): Specify a
	custom interface finalize function when adding the interface so that
	the resources allocated for handling the derived interface properties
	can be freed if the type is a custom interface type.
	(Interface::Interface(const Interface_Class&)): Modify the constructor
	so that when dealing with a custom interface type, it gets a list of
	the properties of the interface to be added and overrides these by
	appending approperiate GValues to the data used to handle
	getting/setting properties that is stored as qdata in the GType.  The
	constructor uses g_param_spec_overrided() to override the properties
	of the implemented interface and g_object_install_property() to
	install the properties.

	* glib/glibmm/property.cc (PropertyBase::install_property): Rewrite
	this method so that the acquired generated id's of custom implemented
	properties does not collide with the id's of properties of implemented
	interfaces that have been overridden in a custom type.  This is done
	by offsetting the acquired generated id (by addition) with the number
	of already existing properties (the ones that have been overridden).
	(custom_get_property_callback): Rewrite this function (which gets
	properties for custom types) so that if the property id is less than
	or equal to the number of overridden interface properties (which would
	mean that an overridden interface property should be gotten) the
	correct overridden interface property is gotten.  Otherwise, a custom
	property should be retrieved, in which case the id is offset (by
	subtraction) when the PropertyBase is retrieved from the id which
	would ensure getting the correct PropertyBase.
	(custom_set_property_callback): Rewrite this function as the above
	custom_get_property_callback was rewritten.

4 files changed, 134 insertions, 20 deletions

diff --git a/glib/glibmm/class.cc b/glib/glibmm/class.cc
index 5cb91301..c31a834b 100644
--- a/glib/glibmm/class.cc
+++ b/glib/glibmm/class.cc
@@ -131,6 +131,28 @@ GType Class::clone_custom_type(const char* custom_type_name) const
   return custom_type;
 }
 
+// Initialize the static quark to store/get custom type properties.
+GQuark Class::properties_quark = g_quark_from_string("gtkmm_CustomObject_properties");
+
+// static
+void Class::interface_finalize_function(void* g_iface, void*)
+{
+  const GType gtype = G_TYPE_FROM_CLASS(g_iface);
+
+  // Free the data related to the properties for the custom type, if any.
+  properties_type* props = static_cast<properties_type*>(g_type_get_qdata(gtype, properties_quark));
+
+  if(props)
+  {
+    for(properties_type::size_type i = 0; i < props->size(); i++)
+    {
+      g_value_unset((*props)[i]);
+      g_free((*props)[i]);
+    }
+    delete props;
+  }
+}
+
 // static
 void Class::custom_class_init_function(void* g_class, void* class_data)
 {
@@ -149,4 +171,3 @@ void Class::custom_class_init_function(void* g_class, void* class_data)
 }
 
 } // namespace Glib
-
diff --git a/glib/glibmm/class.h b/glib/glibmm/class.h
index 2e7345da..7092d506 100644
--- a/glib/glibmm/class.h
+++ b/glib/glibmm/class.h
@@ -25,6 +25,7 @@
 #include <glib-object.h>
 #include <glibmmconfig.h> //Include this here so that the /private/*.h classes have access to GLIBMM_VFUNCS_ENABLED
 
+#include <vector> //For properties that custom types might override.
 
 #ifndef DOXYGEN_SHOULD_SKIP_THIS
 
@@ -66,8 +67,19 @@ protected:
    */
   void register_derived_type(GType base_type, GTypeModule* module);
 
+protected:
+  static void interface_finalize_function(void* g_iface, void* iface_data);
+
 private:
   static void custom_class_init_function(void* g_class, void* class_data);
+
+public:
+#ifndef DOXYGEN_SHOULD_SKIP_THIS
+  // The type that holds the values of the properties of custom types.
+  typedef std::vector<GValue*> properties_type;
+  // The quark used for storing/getting the properties of custom types.
+  static GQuark properties_quark;
+#endif
 };
 
 inline
diff --git a/glib/glibmm/interface.cc b/glib/glibmm/interface.cc
index d284b02a..d378cbe5 100644
--- a/glib/glibmm/interface.cc
+++ b/glib/glibmm/interface.cc
@@ -19,6 +19,7 @@
  */
 
 #include <glibmm/interface.h>
+#include <glibmm/class.h>
 #include <glibmm/private/interface_p.h>
 
 
@@ -35,7 +36,7 @@ void Interface_Class::add_interface(GType instance_type) const
     const GInterfaceInfo interface_info =
     {
       class_init_func_,
-      0, // interface_finalize
+      &Class::interface_finalize_function, // interface_finalize
       0, // interface_data
     };
 
@@ -58,11 +59,42 @@ Interface::Interface(const Interface_Class& interface_class)
 
   if(custom_type_name_ && !is_anonymous_custom_())
   {
-    void *const instance_class = G_OBJECT_GET_CLASS(gobject_);
+    GObjectClass *const instance_class = G_OBJECT_GET_CLASS(gobject_);
+    const GType iface_type = interface_class.get_type();
 
-    if(!g_type_interface_peek(instance_class, interface_class.get_type()))
+    if(!g_type_interface_peek(instance_class, iface_type))
     {
-      interface_class.add_interface(G_OBJECT_CLASS_TYPE(instance_class));
+      void* const g_iface = g_type_default_interface_ref(iface_type);
+
+      const GType custom_type = G_OBJECT_CLASS_TYPE(instance_class);
+      Class::properties_type* props = static_cast<Class::properties_type*>(g_type_get_qdata(custom_type, Class::properties_quark));
+
+      if(!props)
+      {
+        props = new Class::properties_type();
+        g_type_set_qdata(custom_type, Class::properties_quark, props);
+      }
+
+      const guint n_existing_props = props->size();
+
+      guint n_iface_props = 0;
+      GParamSpec** iface_props = g_object_interface_list_properties(g_iface, &n_iface_props);
+
+      for(guint p = 0; p < n_iface_props; p++)
+      {
+        GValue* g_value = g_new0(GValue, 1);
+        g_value_init(g_value, iface_props[p]->value_type);
+        props->push_back(g_value);
+
+        const gchar* prop_name = g_param_spec_get_name(iface_props[p]);
+        GParamSpec* new_spec = g_param_spec_override(prop_name, iface_props[p]);
+        g_object_class_install_property(instance_class, p + 1 + n_existing_props, new_spec);
+      }
+
+      interface_class.add_interface(custom_type);
+
+      g_type_default_interface_unref(g_iface);
+      g_free(iface_props);
     }
   }
 }
diff --git a/glib/glibmm/property.cc b/glib/glibmm/property.cc
index 3b73b6b2..0ae03457 100644
--- a/glib/glibmm/property.cc
+++ b/glib/glibmm/property.cc
@@ -22,6 +22,7 @@
 
 
 #include <glibmm/object.h>
+#include <glibmm/class.h>
 #include <cstddef>
 
 // Temporary hack till GLib gets fixed.
@@ -106,31 +107,68 @@ namespace Glib
 void custom_get_property_callback(GObject* object, unsigned int property_id,
                                   GValue* value, GParamSpec* param_spec)
 {
-  if(Glib::ObjectBase *const wrapper = Glib::ObjectBase::_get_current_wrapper(object))
+  // If the id is zero there is no property to get.
+  g_return_if_fail(property_id != 0);
+
+  GType custom_type = G_OBJECT_TYPE(object);
+
+  Class::properties_type* props = static_cast<Class::properties_type*>(g_type_get_qdata(custom_type, Class::properties_quark));
+  Class::properties_type::size_type props_size = 0;
+
+  if(props) props_size = props->size();
+
+  if(property_id <= props_size)
   {
-    PropertyBase& property = property_from_id(*wrapper, property_id);
+    g_value_copy((*props)[property_id - 1], value);
+  }
+  else
+  {
+    if(Glib::ObjectBase *const wrapper = Glib::ObjectBase::_get_current_wrapper(object))
+    {
+      PropertyBase& property =
+        property_from_id(*wrapper, property_id - props_size);
 
-    if((property.object_ == wrapper) && (property.param_spec_ == param_spec))
-      g_value_copy(property.value_.gobj(), value);
-    else
-      G_OBJECT_WARN_INVALID_PROPERTY_ID(object, property_id, param_spec);
+      if((property.object_ == wrapper) && (property.param_spec_ == param_spec))
+        g_value_copy(property.value_.gobj(), value);
+      else
+        G_OBJECT_WARN_INVALID_PROPERTY_ID(object, property_id, param_spec);
+    }
   }
 }
 
 void custom_set_property_callback(GObject* object, unsigned int property_id,
                                   const GValue* value, GParamSpec* param_spec)
 {
-  if(Glib::ObjectBase *const wrapper = Glib::ObjectBase::_get_current_wrapper(object))
-  {
-    PropertyBase& property = property_from_id(*wrapper, property_id);
+  // If the id is zero there is no property to get.
+  g_return_if_fail(property_id != 0);
 
-    if((property.object_ == wrapper) && (property.param_spec_ == param_spec))
+  GType custom_type = G_OBJECT_TYPE(object);
+
+  Class::properties_type* props = static_cast<Class::properties_type*>(g_type_get_qdata(custom_type, Class::properties_quark));
+  Class::properties_type::size_type props_size = 0;
+
+  if(props) props_size = props->size();
+
+  if(property_id <= props_size)
+  {
+    g_value_copy(value, (*props)[property_id - 1]);
+    g_object_notify(object, g_param_spec_get_name(param_spec));
+  }
+  else
+  {
+    if(Glib::ObjectBase *const wrapper = Glib::ObjectBase::_get_current_wrapper(object))
     {
-      g_value_copy(value, property.value_.gobj());
-      g_object_notify(object, g_param_spec_get_name(param_spec));
+      PropertyBase& property =
+        property_from_id(*wrapper, property_id - props_size);
+
+      if((property.object_ == wrapper) && (property.param_spec_ == param_spec))
+      {
+        g_value_copy(value, property.value_.gobj());
+        g_object_notify(object, g_param_spec_get_name(param_spec));
+      }
+      else
+        G_OBJECT_WARN_INVALID_PROPERTY_ID(object, property_id, param_spec);
     }
-    else
-      G_OBJECT_WARN_INVALID_PROPERTY_ID(object, property_id, param_spec);
   }
 }
 
@@ -171,7 +209,18 @@ void PropertyBase::install_property(GParamSpec* param_spec)
 {
   g_return_if_fail(param_spec != 0);
 
-  const unsigned int property_id = property_to_id(*object_, *this);
+  // Ensure that there would not be id clashes with possible existing
+  // properties overridden from implemented interfaces if dealing with a custom
+  // type by offsetting the generated id with the number of already existing
+  // properties.
+
+  GType gtype = G_OBJECT_TYPE(object_->gobj());
+  Class::properties_type* props = static_cast<Class::properties_type*>(g_type_get_qdata(gtype, Class::properties_quark));
+
+  Class::properties_type::size_type props_size = 0;
+  if(props) props_size = props->size();
+
+  const unsigned int property_id = property_to_id(*object_, *this) + props_size;
 
   g_object_class_install_property(G_OBJECT_GET_CLASS(object_->gobj()), property_id, param_spec);