swfdec/swfdec_gc_object.c

   1 /* Swfdec
   2  * Copyright (C) 2008 Benjamin Otte <otte@gnome.org>
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor,
  17  * Boston, MA  02110-1301  USA
  18  */
  19
  20 #ifdef HAVE_CONFIG_H
  21 #include "config.h"
  22 #endif
  23
  24 #include <string.h>
  25
  26 #include "swfdec_gc_object.h"
  27 #include "swfdec_as_context.h"
  28 #include "swfdec_as_internal.h"
  29
  30 /**
  31  * SECTION:SwfdecGcObject
  32  * @title: SwfdecGcObject
  33  * @short_description: the base object type for garbage-collected objects
  34  *
  35  * This type is the basic garbage-collected object in Swfdec. It contains the
  36  * simple facilities for required by the garbage collector. The initial
  37  * reference of this object will be owned by the context that created it and
  38  * will be released automatically when no other object references it anymore
  39  * in the garbage collection cycle.
  40  *
  41  * Note that you cannot know the lifetime of a #SwfdecGcObject, since scripts
  42  * may assign it as a variable to other objects. So you should not assume to
  43  * know when an object gets removed.
  44  */
  45
  46 /**
  47  * SwfdecGcObject:
  48  *
  49  * If you want to add custom objects to the garbage collection lifecycle, you
  50  * need to subclass this object as this object is abstract. Note that you have
  51  * to provide a valid #SwfdecAsContext whenever you construct objects of this
  52  * type.
  53  */
  54
  55 /**
  56  * SwfdecGcObjectClass:
  57  * @mark: Called in the mark phase of garbage collection. Mark all the
  58  *        garbage-collected object you still use here using the marking
  59  *        functions such as swfdec_gc_object_mark() or swfdec_as_string_mark()
  60  *
  61  * This is the base class for garbage-collected objects.
  62  */
  63
  64 enum {
  65   PROP_0,
  66   PROP_CONTEXT
  67 };
  68
  69 G_DEFINE_ABSTRACT_TYPE (SwfdecGcObject, swfdec_gc_object, G_TYPE_OBJECT)
  70
  71 static gsize
  72 swfdec_gc_object_get_size (SwfdecGcObject *object)
  73 {
  74   GTypeQuery query;
  75
  76   /* FIXME: This only uses the size of the public instance but doesn't include
  77    * private members. http://bugzilla.gnome.org/show_bug.cgi?id=354457 blocks
  78    * this. */
  79   g_type_query (G_OBJECT_TYPE (object), &query);
  80   return query.instance_size;
  81 }
  82
  83 static void
  84 swfdec_gc_object_dispose (GObject *gobject)
  85 {
  86   SwfdecGcObject *object = SWFDEC_GC_OBJECT (gobject);
  87
  88   swfdec_as_context_unuse_mem (object->context, swfdec_gc_object_get_size (object));
  89   G_OBJECT_CLASS (swfdec_gc_object_parent_class)->dispose (gobject);
  90 }
  91
  92 static void
  93 swfdec_gc_object_do_mark (SwfdecGcObject *object)
  94 {
  95 }
  96
  97 static GObject *
  98 swfdec_gc_object_constructor (GType type, guint n_construct_properties,
  99     GObjectConstructParam *construct_properties)
 100 {
 101   GObject *gobject;
 102   SwfdecGcObject *object;
 103   SwfdecAsContext *context;
 104
 105   gobject = G_OBJECT_CLASS (swfdec_gc_object_parent_class)->constructor (type,
 106       n_construct_properties, construct_properties);
 107   object = SWFDEC_GC_OBJECT (gobject);
 108
 109   context = object->context;
 110   swfdec_as_context_use_mem (context, swfdec_gc_object_get_size (object));
 111   object->next = context->gc_objects;
 112   context->gc_objects = object;
 113
 114   return gobject;
 115 }
 116
 117 static void
 118 swfdec_gc_object_get_property (GObject *object, guint param_id, GValue *value,
 119     GParamSpec * pspec)
 120 {
 121   SwfdecGcObject *gc = SWFDEC_GC_OBJECT (object);
 122
 123   switch (param_id) {
 124     case PROP_CONTEXT:
 125       g_value_set_object (value, gc->context);
 126       break;
 127     default:
 128       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, param_id, pspec);
 129       break;
 130   }
 131 }
 132
 133 static void
 134 swfdec_gc_object_set_property (GObject *object, guint param_id, const GValue *value,
 135     GParamSpec * pspec)
 136 {
 137   SwfdecGcObject *gc = SWFDEC_GC_OBJECT (object);
 138
 139   switch (param_id) {
 140     case PROP_CONTEXT:
 141       gc->context = g_value_get_object (value);
 142       g_assert (gc->context != NULL);
 143       break;
 144     default:
 145       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, param_id, pspec);
 146       break;
 147   }
 148 }
 149
 150 static void
 151 swfdec_gc_object_class_init (SwfdecGcObjectClass *klass)
 152 {
 153   GObjectClass *object_class = G_OBJECT_CLASS (klass);
 154
 155   object_class->dispose = swfdec_gc_object_dispose;
 156   object_class->set_property = swfdec_gc_object_set_property;
 157   object_class->get_property = swfdec_gc_object_get_property;
 158   object_class->constructor = swfdec_gc_object_constructor;
 159
 160   g_object_class_install_property (object_class, PROP_CONTEXT,
 161       g_param_spec_object ("context", "context", "context managing this object",
 162           SWFDEC_TYPE_AS_CONTEXT, G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY));
 163
 164   klass->mark = swfdec_gc_object_do_mark;
 165 }
 166
 167 static void
 168 swfdec_gc_object_init (SwfdecGcObject *object)
 169 {
 170 }
 171
 172 /**
 173  * swfdec_gc_object_get_context:
 174  * @object: a #SwfdecGcObject. This function takes a gpointer argument only to
 175  *          save you from having to cast it manually. For language bindings,
 176  *          please treat this argument as having the #SwfdecGcObject type.
 177  *
 178  * Gets the context that garbage-collects this object.
 179  *
 180  * Returns: the context this object belongs to
 181  **/
 182 SwfdecAsContext *
 183 swfdec_gc_object_get_context (gpointer object)
 184 {
 185   g_return_val_if_fail (SWFDEC_IS_GC_OBJECT (object), NULL);
 186
 187   return SWFDEC_GC_OBJECT (object)->context;
 188 }
 189
 190 /**
 191  * swfdec_gc_object_mark:
 192  * @object: a #SwfdecGcObject. This function takes a gpointer argument only to
 193  *          save you from having to cast it manually. For language bindings,
 194  *          please treat this argument as having the #SwfdecGcObject type.
 195  *
 196  * Mark @object as being in use. Calling this function is only valid during
 197  * the marking phase of garbage collection.
 198  **/
 199 void
 200 swfdec_gc_object_mark (gpointer object)
 201 {
 202   SwfdecGcObject *gc = object;
 203   SwfdecGcObjectClass *klass;
 204
 205   g_return_if_fail (SWFDEC_IS_GC_OBJECT (object));
 206
 207   if (gc->flags & SWFDEC_AS_GC_MARK)
 208     return;
 209   gc->flags |= SWFDEC_AS_GC_MARK;
 210   klass = SWFDEC_GC_OBJECT_GET_CLASS (gc);
 211   g_assert (klass->mark);
 212   klass->mark (gc);
 213 }
 214