[gtk+/wip/cssvalue: 40/141] cssvalue: Make the structure vtable-based

[Benjamin Otte <otte src gnome org>]

commit b24b634362b0bae7e78d99cfff72e17273bf3f68
Author: Benjamin Otte <otte redhat com>
Date:   Mon Mar 26 06:13:57 2012 +0200

    cssvalue: Make the structure vtable-based
    
    Don't use real classes, just a vtable.

 gtk/gtkcssvalue.c        |   92 ++++++++++++++++++++++++++++-----------------
 gtk/gtkcssvalueprivate.h |   19 +++++++++-
 2 files changed, 75 insertions(+), 36 deletions(-)
---
diff --git a/gtk/gtkcssvalue.c b/gtk/gtkcssvalue.c
index a3854f2..ac69ea6 100644
--- a/gtk/gtkcssvalue.c
+++ b/gtk/gtkcssvalue.c
@@ -25,9 +25,10 @@
 
 #include "fallback-c89.c"
 
+typedef struct _GtkCssValue GtkCssValue;
 struct _GtkCssValue
 {
-  volatile gint ref_count;
+  GTK_CSS_VALUE_BASE
   GType type;
   union {
     gpointer ptr;
@@ -38,16 +39,34 @@ struct _GtkCssValue
   } u;
 };
 
+static void
+gtk_css_value_default_free (GtkCssValue *value)
+{
+  GType type = value->type;
+
+  if (g_type_is_a (type, G_TYPE_OBJECT) && value->u.ptr != NULL)
+    g_object_unref (value->u.ptr);
+  else if (g_type_is_a (type, G_TYPE_BOXED) && value->u.ptr != NULL)
+    g_boxed_free (type, value->u.ptr);
+  else if (g_type_is_a (type, G_TYPE_STRING))
+    g_free (value->u.ptr);
+
+  g_slice_free (GtkCssValue, value);
+}
+
+static const GtkCssValueClass GTK_CSS_VALUE_DEFAULT = {
+  gtk_css_value_default_free
+};
+
 G_DEFINE_BOXED_TYPE (GtkCssValue, _gtk_css_value, _gtk_css_value_ref, _gtk_css_value_unref)
 
 static GtkCssValue *
-_gtk_css_value_new (GType type)
+gtk_css_value_new (GType type)
 {
   GtkCssValue *value;
 
-  value = g_slice_new0 (GtkCssValue);
+  value = _gtk_css_value_new (GtkCssValue, &GTK_CSS_VALUE_DEFAULT);
 
-  value->ref_count = 1;
   value->type = type;
 
   return value;
@@ -70,7 +89,7 @@ _gtk_css_value_new_from_gvalue (const GValue *g_value)
     value = _gtk_css_value_new_from_number (g_value_get_boxed (g_value));
   else
     {
-      value = _gtk_css_value_new (type);
+      value = gtk_css_value_new (type);
 
       if (g_type_is_a (type, G_TYPE_OBJECT))
 	value->u.ptr = g_value_dup_object (g_value);
@@ -122,7 +141,7 @@ _gtk_css_value_new_take_gvalue (GValue *g_value)
     }
   else
     {
-      value = _gtk_css_value_new (type);
+      value = gtk_css_value_new (type);
 
       if (g_type_is_a (type, G_TYPE_OBJECT))
 	value->u.ptr = g_value_get_object (g_value);
@@ -161,14 +180,14 @@ _gtk_css_value_new_from_int (gint val)
     {
       if (singletons[val] == NULL)
 	{
-	  value = _gtk_css_value_new (G_TYPE_INT);
+	  value = gtk_css_value_new (G_TYPE_INT);
 	  value->u.gint = val;
 	  singletons[val] = value;
 	}
       return _gtk_css_value_ref (singletons[val]);
     }
 
-  value = _gtk_css_value_new (G_TYPE_INT);
+  value = gtk_css_value_new (G_TYPE_INT);
   value->u.gint = val;
 
   return value;
@@ -179,7 +198,7 @@ _gtk_css_value_new_take_string (char *string)
 {
   GtkCssValue *value;
 
-  value = _gtk_css_value_new (G_TYPE_STRING);
+  value = gtk_css_value_new (G_TYPE_STRING);
   value->u.ptr = string;
 
   return value;
@@ -199,7 +218,7 @@ _gtk_css_value_new_from_border (const GtkBorder *border)
 {
   GtkCssValue *value;
 
-  value = _gtk_css_value_new (GTK_TYPE_BORDER);
+  value = gtk_css_value_new (GTK_TYPE_BORDER);
   value->u.ptr = g_boxed_copy0 (GTK_TYPE_BORDER, border);
 
   return value;
@@ -210,7 +229,7 @@ _gtk_css_value_new_take_pattern (cairo_pattern_t *v)
 {
   GtkCssValue *value;
 
-  value = _gtk_css_value_new (CAIRO_GOBJECT_TYPE_PATTERN);
+  value = gtk_css_value_new (CAIRO_GOBJECT_TYPE_PATTERN);
   value->u.ptr = v;
 
   return value;
@@ -221,7 +240,7 @@ _gtk_css_value_new_from_pattern (const cairo_pattern_t *v)
 {
   GtkCssValue *value;
 
-  value = _gtk_css_value_new (CAIRO_GOBJECT_TYPE_PATTERN);
+  value = gtk_css_value_new (CAIRO_GOBJECT_TYPE_PATTERN);
   value->u.ptr = g_boxed_copy0 (CAIRO_GOBJECT_TYPE_PATTERN, v);
 
   return value;
@@ -232,7 +251,7 @@ _gtk_css_value_new_take_shadow (GtkShadow *v)
 {
   GtkCssValue *value;
 
-  value = _gtk_css_value_new (GTK_TYPE_SHADOW);
+  value = gtk_css_value_new (GTK_TYPE_SHADOW);
   value->u.ptr = v;
 
   return value;
@@ -243,7 +262,7 @@ _gtk_css_value_new_take_font_description (PangoFontDescription *v)
 {
   GtkCssValue *value;
 
-  value = _gtk_css_value_new (PANGO_TYPE_FONT_DESCRIPTION);
+  value = gtk_css_value_new (PANGO_TYPE_FONT_DESCRIPTION);
   value->u.ptr = v;
 
   return value;
@@ -254,7 +273,7 @@ _gtk_css_value_new_take_image (GtkCssImage *v)
 {
   GtkCssValue *value;
 
-  value = _gtk_css_value_new (GTK_TYPE_CSS_IMAGE);
+  value = gtk_css_value_new (GTK_TYPE_CSS_IMAGE);
   value->u.ptr = v;
 
   return value;
@@ -272,7 +291,7 @@ _gtk_css_value_new_from_number (const GtkCssNumber *v)
     {
       if (zero_singleton == NULL)
 	{
-	  value = _gtk_css_value_new (GTK_TYPE_CSS_NUMBER);
+	  value = gtk_css_value_new (GTK_TYPE_CSS_NUMBER);
 	  value->u.ptr = g_boxed_copy0 (GTK_TYPE_CSS_NUMBER, v);
 	  zero_singleton = value;
 	}
@@ -289,7 +308,7 @@ _gtk_css_value_new_from_number (const GtkCssNumber *v)
       int i = round (v->value);
       if (px_singletons[i] == NULL)
 	{
-	  value = _gtk_css_value_new (GTK_TYPE_CSS_NUMBER);
+	  value = gtk_css_value_new (GTK_TYPE_CSS_NUMBER);
 	  value->u.ptr = g_boxed_copy0 (GTK_TYPE_CSS_NUMBER, v);
 	  px_singletons[i] = value;
 	}
@@ -297,7 +316,7 @@ _gtk_css_value_new_from_number (const GtkCssNumber *v)
       return _gtk_css_value_ref (px_singletons[i]);
     }
 
-  value = _gtk_css_value_new (GTK_TYPE_CSS_NUMBER);
+  value = gtk_css_value_new (GTK_TYPE_CSS_NUMBER);
   value->u.ptr = g_boxed_copy0 (GTK_TYPE_CSS_NUMBER, v);
 
   return value;
@@ -308,7 +327,7 @@ _gtk_css_value_new_from_rgba (const GdkRGBA *v)
 {
   GtkCssValue *value;
 
-  value = _gtk_css_value_new (GDK_TYPE_RGBA);
+  value = gtk_css_value_new (GDK_TYPE_RGBA);
   value->u.ptr = g_boxed_copy0 (GDK_TYPE_RGBA, v);
 
   return value;
@@ -319,7 +338,7 @@ _gtk_css_value_new_from_color (const GdkColor *v)
 {
   GtkCssValue *value;
 
-  value = _gtk_css_value_new (GDK_TYPE_COLOR);
+  value = gtk_css_value_new (GDK_TYPE_COLOR);
   value->u.ptr = g_boxed_copy0 (GDK_TYPE_COLOR, v);
 
   return value;
@@ -330,7 +349,7 @@ _gtk_css_value_new_from_background_size (const GtkCssBackgroundSize *v)
 {
   GtkCssValue *value;
 
-  value = _gtk_css_value_new (GTK_TYPE_CSS_BACKGROUND_SIZE);
+  value = gtk_css_value_new (GTK_TYPE_CSS_BACKGROUND_SIZE);
   value->u.ptr = g_boxed_copy0 (GTK_TYPE_CSS_BACKGROUND_SIZE, v);
 
   return value;
@@ -341,7 +360,7 @@ _gtk_css_value_new_from_background_position (const GtkCssBackgroundPosition *v)
 {
   GtkCssValue *value;
 
-  value = _gtk_css_value_new (GTK_TYPE_CSS_BACKGROUND_POSITION);
+  value = gtk_css_value_new (GTK_TYPE_CSS_BACKGROUND_POSITION);
   value->u.ptr = g_boxed_copy0 (GTK_TYPE_CSS_BACKGROUND_POSITION, v);
 
   return value;
@@ -352,13 +371,27 @@ _gtk_css_value_new_take_symbolic_color (GtkSymbolicColor *v)
 {
   GtkCssValue *value;
 
-  value = _gtk_css_value_new (GTK_TYPE_SYMBOLIC_COLOR);
+  value = gtk_css_value_new (GTK_TYPE_SYMBOLIC_COLOR);
   value->u.ptr = v;
 
   return value;
 }
 
 GtkCssValue *
+_gtk_css_value_alloc (const GtkCssValueClass *klass,
+                      gsize                   size)
+{
+  GtkCssValue *value;
+
+  value = g_slice_alloc0 (size);
+
+  value->class = klass;
+  value->ref_count = 1;
+
+  return value;
+}
+
+GtkCssValue *
 _gtk_css_value_ref (GtkCssValue *value)
 {
   g_return_val_if_fail (value != NULL, NULL);
@@ -371,24 +404,13 @@ _gtk_css_value_ref (GtkCssValue *value)
 void
 _gtk_css_value_unref (GtkCssValue *value)
 {
-  GType type;
-
   if (value == NULL)
     return;
 
   if (!g_atomic_int_dec_and_test (&value->ref_count))
     return;
 
-  type = value->type;
-
-  if (g_type_is_a (type, G_TYPE_OBJECT) && value->u.ptr != NULL)
-    g_object_unref (value->u.ptr);
-  else if (g_type_is_a (type, G_TYPE_BOXED) && value->u.ptr != NULL)
-    g_boxed_free (type, value->u.ptr);
-  else if (g_type_is_a (type, G_TYPE_STRING))
-    g_free (value->u.ptr);
-
-  g_slice_free (GtkCssValue, value);
+  value->class->free (value);
 }
 
 GType
diff --git a/gtk/gtkcssvalueprivate.h b/gtk/gtkcssvalueprivate.h
index d925b71..7fcb066 100644
--- a/gtk/gtkcssvalueprivate.h
+++ b/gtk/gtkcssvalueprivate.h
@@ -35,13 +35,30 @@ G_BEGIN_DECLS
 #define GTK_IS_CSS_VALUE_CLASS(obj)  (G_TYPE_CHECK_CLASS_TYPE (obj, GTK_TYPE_CSS_VALUE))
 #define GTK_CSS_VALUE_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), GTK_TYPE_CSS_VALUE, GtkCssValueClass))
 
+/* A GtkCssValue is a refcounted immutable value type */
+
 typedef struct _GtkCssValue           GtkCssValue;
+typedef struct _GtkCssValueBase       GtkCssValueBase;
+typedef struct _GtkCssValueClass      GtkCssValueClass;
 
-/* A GtkCssValue is a refcounted immutable value type */
+/* using define instead of struct here so compilers get the packing right */
+#define GTK_CSS_VALUE_BASE \
+  const GtkCssValueClass *class; \
+  volatile gint ref_count;
+
+struct _GtkCssValueClass {
+  void          (* free)                              (GtkCssValue                *value);
+};
 
 GType        _gtk_css_value_get_type                  (void) G_GNUC_CONST;
+
+GtkCssValue *_gtk_css_value_alloc                     (const GtkCssValueClass     *klass,
+                                                       gsize                       size);
+#define _gtk_css_value_new(_name, _klass) ((_name *) _gtk_css_value_alloc ((_klass), sizeof (_name)))
+
 GtkCssValue *_gtk_css_value_ref                       (GtkCssValue                *value);
 void         _gtk_css_value_unref                     (GtkCssValue                *value);
+
 GType        _gtk_css_value_get_content_type          (GtkCssValue                *value);
 gboolean     _gtk_css_value_holds                     (GtkCssValue                *value,
 						       GType                       type);