* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General
- * Public License along with this library; if not, write to the
- * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
- * Boston, MA 02111-1307, USA.
+ * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
/*
#include "gparamspecs.h"
#include "gvaluetypes.h"
#include "gobject_trace.h"
+#include "gconstructor.h"
/**
* SECTION:objects
+ * @title: GObject
* @short_description: The base object type
* @see_also: #GParamSpecObject, g_param_spec_object()
- * @title: The Base Object Type
*
* GObject is the fundamental type providing the common attributes and
* methods for all object types in GTK+, Pango and other libraries
* based on GObject. The GObject class provides methods for object
* construction and destruction, property access methods, and signal
- * support. Signals are described in detail in <xref
- * linkend="gobject-Signals"/>.
+ * support. Signals are described in detail [here][gobject-Signals].
+ *
+ * ## Floating references # {#floating-ref}
*
- * <para id="floating-ref">
* GInitiallyUnowned is derived from GObject. The only difference between
* the two is that the initial reference of a GInitiallyUnowned is flagged
- * as a <firstterm>floating</firstterm> reference.
- * This means that it is not specifically claimed to be "owned" by
- * any code portion. The main motivation for providing floating references is
- * C convenience. In particular, it allows code to be written as:
- * |[
+ * as a "floating" reference. This means that it is not specifically
+ * claimed to be "owned" by any code portion. The main motivation for
+ * providing floating references is C convenience. In particular, it
+ * allows code to be written as:
+ * |[<!-- language="C" -->
* container = create_container ();
* container_add_child (container, create_child());
* ]|
- * If <function>container_add_child()</function> will g_object_ref_sink() the
- * passed in child, no reference of the newly created child is leaked.
- * Without floating references, <function>container_add_child()</function>
- * can only g_object_ref() the new child, so to implement this code without
- * reference leaks, it would have to be written as:
- * |[
+ * If container_add_child() calls g_object_ref_sink() on the passed-in child,
+ * no reference of the newly created child is leaked. Without floating
+ * references, container_add_child() can only g_object_ref() the new child,
+ * so to implement this code without reference leaks, it would have to be
+ * written as:
+ * |[<!-- language="C" -->
* Child *child;
* container = create_container ();
* child = create_child ();
* container_add_child (container, child);
* g_object_unref (child);
* ]|
- * The floating reference can be converted into
- * an ordinary reference by calling g_object_ref_sink().
- * For already sunken objects (objects that don't have a floating reference
- * anymore), g_object_ref_sink() is equivalent to g_object_ref() and returns
- * a new reference.
+ * The floating reference can be converted into an ordinary reference by
+ * calling g_object_ref_sink(). For already sunken objects (objects that
+ * don't have a floating reference anymore), g_object_ref_sink() is equivalent
+ * to g_object_ref() and returns a new reference.
+ *
* Since floating references are useful almost exclusively for C convenience,
* language bindings that provide automated reference and memory ownership
* maintenance (such as smart pointers or garbage collection) should not
* expose floating references in their API.
- * </para>
*
* Some object implementations may need to save an objects floating state
* across certain code portions (an example is #GtkMenu), to achieve this,
* the following sequence can be used:
*
- * |[
- * /* save floating state */
+ * |[<!-- language="C" -->
+ * // save floating state
* gboolean was_floating = g_object_is_floating (object);
* g_object_ref_sink (object);
- * /* protected code portion */
- * ...;
- * /* restore floating state */
+ * // protected code portion
+ *
+ * ...
+ *
+ * // restore floating state
* if (was_floating)
* g_object_force_floating (object);
- * g_object_unref (object); /* release previously acquired reference */
+ * else
+ * g_object_unref (object); // release previously acquired reference
* ]|
*/
static guint object_floating_flag_handler (GObject *object,
gint job);
-static void object_interface_check_properties (gpointer func_data,
+static void object_interface_check_properties (gpointer check_data,
gpointer g_iface);
/* --- typedefs --- */
static GQuark quark_weak_refs = 0;
static GQuark quark_toggle_refs = 0;
static GQuark quark_notify_queue;
+static GQuark quark_in_construction;
static GParamSpecPool *pspec_pool = NULL;
static gulong gobject_signals[LAST_SIGNAL] = { 0, };
static guint (*floating_flag_handler) (GObject*, gint) = object_floating_flag_handler;
-G_LOCK_DEFINE_STATIC (construction_mutex);
-static GSList *construction_objects = NULL;
+/* qdata pointing to GSList<GWeakRef *>, protected by weak_locations_lock */
+static GQuark quark_weak_locations = 0;
+static GRWLock weak_locations_lock;
G_LOCK_DEFINE_STATIC(notify_lock);
#ifdef G_ENABLE_DEBUG
#define IF_DEBUG(debug_type) if (_g_type_debug_flags & G_TYPE_DEBUG_ ## debug_type)
G_LOCK_DEFINE_STATIC (debug_objects);
-static volatile GObject *g_trap_object_ref = NULL;
static guint debug_objects_count = 0;
static GHashTable *debug_objects_ht = NULL;
object->ref_count);
}
+#ifdef G_HAS_CONSTRUCTORS
+#ifdef G_DEFINE_DESTRUCTOR_NEEDS_PRAGMA
+#pragma G_DEFINE_DESTRUCTOR_PRAGMA_ARGS(debug_objects_atexit)
+#endif
+G_DEFINE_DESTRUCTOR(debug_objects_atexit)
+#endif /* G_HAS_CONSTRUCTORS */
+
static void
debug_objects_atexit (void)
{
IF_DEBUG (OBJECTS)
{
debug_objects_ht = g_hash_table_new (g_direct_hash, NULL);
+#ifndef G_HAS_CONSTRUCTORS
g_atexit (debug_objects_atexit);
+#endif /* G_HAS_CONSTRUCTORS */
}
#endif /* G_ENABLE_DEBUG */
}
quark_closure_array = g_quark_from_static_string ("GObject-closure-array");
quark_weak_refs = g_quark_from_static_string ("GObject-weak-references");
+ quark_weak_locations = g_quark_from_static_string ("GObject-weak-locations");
quark_toggle_refs = g_quark_from_static_string ("GObject-toggle-references");
quark_notify_queue = g_quark_from_static_string ("GObject-notify-queue");
+ quark_in_construction = g_quark_from_static_string ("GObject-in-construction");
pspec_pool = g_param_spec_pool_new (TRUE);
class->constructor = g_object_constructor;
* This signal is typically used to obtain change notification for a
* single property, by specifying the property name as a detail in the
* g_signal_connect() call, like this:
- * |[
+ * |[<!-- language="C" -->
* g_signal_connect (text_view->buffer, "notify::paste-target-list",
* G_CALLBACK (gtk_text_view_target_list_notify),
* text_view)
* ]|
* It is important to note that you must use
- * <link linkend="canonical-parameter-name">canonical</link> parameter names as
+ * [canonical][canonical-parameter-name] parameter names as
* detail strings for the notify signal.
*/
gobject_signals[NOTIFY] =
{
if (g_param_spec_pool_lookup (pspec_pool, pspec->name, g_type, FALSE))
{
- g_warning ("When installing property: type `%s' already has a property named `%s'",
+ g_warning ("When installing property: type '%s' already has a property named '%s'",
g_type_name (g_type),
pspec->name);
return;
* @property_id: the id for the new property
* @pspec: the #GParamSpec for the new property
*
- * Installs a new property. This is usually done in the class initializer.
+ * Installs a new property.
+ *
+ * All properties should be installed during the class initializer. It
+ * is possible to install properties after that, but doing so is not
+ * recommend, and specifically, is not guaranteed to be thread-safe vs.
+ * use of properties on the same type on other threads.
*
* Note that it is possible to redefine a property in a derived class,
* by installing a property with the same name. This can be useful at times,
g_return_if_fail (G_IS_PARAM_SPEC (pspec));
if (CLASS_HAS_DERIVED_CLASS (class))
- g_error ("Attempt to add property %s::%s to class after it was derived",
- G_OBJECT_CLASS_NAME (class), pspec->name);
+ g_error ("Attempt to add property %s::%s to class after it was derived", G_OBJECT_CLASS_NAME (class), pspec->name);
class->flags |= CLASS_HAS_PROPS_FLAG;
+ g_return_if_fail (pspec->flags & (G_PARAM_READABLE | G_PARAM_WRITABLE));
if (pspec->flags & G_PARAM_WRITABLE)
g_return_if_fail (class->set_property != NULL);
if (pspec->flags & G_PARAM_READABLE)
install_property_internal (G_OBJECT_CLASS_TYPE (class), property_id, pspec);
if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))
- class->construct_properties = g_slist_prepend (class->construct_properties, pspec);
+ class->construct_properties = g_slist_append (class->construct_properties, pspec);
/* for property overrides of construct properties, we have to get rid
* of the overidden inherited construct property
/**
* g_object_class_install_properties:
* @oclass: a #GObjectClass
- * @n_pspecs: the length of the #GParamSpec<!-- -->s array
- * @pspecs: (array length=n_pspecs): the #GParamSpec<!-- -->s array
+ * @n_pspecs: the length of the #GParamSpecs array
+ * @pspecs: (array length=n_pspecs): the #GParamSpecs array
* defining the new properties
*
- * Installs new properties from an array of #GParamSpec<!-- -->s. This is
- * usually done in the class initializer.
+ * Installs new properties from an array of #GParamSpecs.
+ *
+ * All properties should be installed during the class initializer. It
+ * is possible to install properties after that, but doing so is not
+ * recommend, and specifically, is not guaranteed to be thread-safe vs.
+ * use of properties on the same type on other threads.
*
* The property id of each property is the index of each #GParamSpec in
* the @pspecs array.
* be used to store a #GParamSpec.
*
* This function should be used if you plan to use a static array of
- * #GParamSpec<!-- -->s and g_object_notify_by_pspec(). For instance, this
+ * #GParamSpecs and g_object_notify_by_pspec(). For instance, this
* class initialization:
*
- * |[
+ * |[<!-- language="C" -->
* enum {
* PROP_0, PROP_FOO, PROP_BAR, N_PROPERTIES
* };
*
* allows calling g_object_notify_by_pspec() to notify of property changes:
*
- * |[
+ * |[<!-- language="C" -->
* void
* my_object_set_foo (MyObject *self, gint foo)
* {
install_property_internal (oclass_type, i, pspec);
if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))
- oclass->construct_properties = g_slist_prepend (oclass->construct_properties, pspec);
+ oclass->construct_properties = g_slist_append (oclass->construct_properties, pspec);
/* for property overrides of construct properties, we have to get rid
* of the overidden inherited construct property
g_return_if_fail (G_IS_PARAM_SPEC (pspec));
g_return_if_fail (!G_IS_PARAM_SPEC_OVERRIDE (pspec)); /* paranoid */
g_return_if_fail (PARAM_SPEC_PARAM_ID (pspec) == 0); /* paranoid */
-
+
+ g_return_if_fail (pspec->flags & (G_PARAM_READABLE | G_PARAM_WRITABLE));
+ if (pspec->flags & G_PARAM_CONSTRUCT)
+ g_return_if_fail ((pspec->flags & G_PARAM_CONSTRUCT_ONLY) == 0);
+ if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))
+ g_return_if_fail (pspec->flags & G_PARAM_WRITABLE);
+
install_property_internal (iface_class->g_type, 0, pspec);
}
* @name: the name of a property registered in a parent class or
* in an interface of this class.
*
- * Registers @property_id as referring to a property with the
- * name @name in a parent class or in an interface implemented
- * by @oclass. This allows this class to <firstterm>override</firstterm>
- * a property implementation in a parent class or to provide
- * the implementation of a property from an interface.
+ * Registers @property_id as referring to a property with the name
+ * @name in a parent class or in an interface implemented by @oclass.
+ * This allows this class to "override" a property implementation in
+ * a parent class or to provide the implementation of a property from
+ * an interface.
*
- * <note>
* Internally, overriding is implemented by creating a property of type
* #GParamSpecOverride; generally operations that query the properties of
* the object class, such as g_object_class_find_property() or
* correct. For virtually all uses, this makes no difference. If you
* need to get the overridden property, you can call
* g_param_spec_get_redirect_target().
- * </note>
*
* Since: 2.4
*/
return pspecs;
}
+static inline gboolean
+object_in_construction (GObject *object)
+{
+ return g_datalist_id_get_data (&object->qdata, quark_in_construction) != NULL;
+}
+
static void
g_object_init (GObject *object,
GObjectClass *class)
if (CLASS_HAS_CUSTOM_CONSTRUCTOR (class))
{
- /* enter construction list for notify_queue_thaw() and to allow construct-only properties */
- G_LOCK (construction_mutex);
- construction_objects = g_slist_prepend (construction_objects, object);
- G_UNLOCK (construction_mutex);
+ /* mark object in-construction for notify_queue_thaw() and to allow construct-only properties */
+ g_datalist_id_set_data (&object->qdata, quark_in_construction, object);
}
#ifdef G_ENABLE_DEBUG
static void
g_object_finalize (GObject *object)
{
+ if (object_in_construction (object))
+ {
+ g_critical ("object %s %p finalized while still in-construction",
+ G_OBJECT_TYPE_NAME (object), object);
+ }
+
g_datalist_clear (&object->qdata);
#ifdef G_ENABLE_DEBUG
* Increases the freeze count on @object. If the freeze count is
* non-zero, the emission of "notify" signals on @object is
* stopped. The signals are queued until the freeze count is decreased
- * to zero.
+ * to zero. Duplicate notifications are squashed so that at most one
+ * #GObject::notify signal is emitted for each property modified while the
+ * object is frozen.
*
* This is necessary for accessors that modify multiple properties to prevent
* premature notification while the object is still being modified.
* When possible, eg. when signaling a property change from within the class
* that registered the property, you should use g_object_notify_by_pspec()
* instead.
+ *
+ * Note that emission of the notify signal may be blocked with
+ * g_object_freeze_notify(). In this case, the signal emissions are queued
+ * and will be emitted (in reverse order) when g_object_thaw_notify() is
+ * called.
*/
void
g_object_notify (GObject *object,
TRUE);
if (!pspec)
- g_warning ("%s: object class `%s' has no property named `%s'",
+ g_warning ("%s: object class '%s' has no property named '%s'",
G_STRFUNC,
G_OBJECT_TYPE_NAME (object),
property_name);
* instead, is to store the GParamSpec used with
* g_object_class_install_property() inside a static array, e.g.:
*
- *|[
+ *|[<!-- language="C" -->
* enum
* {
* PROP_0,
*
* and then notify a change on the "foo" property with:
*
- * |[
+ * |[<!-- language="C" -->
* g_object_notify_by_pspec (self, properties[PROP_FOO]);
* ]|
*
g_return_if_fail (G_IS_OBJECT (object));
g_return_if_fail (G_IS_PARAM_SPEC (pspec));
+ if (g_atomic_int_get (&object->ref_count) == 0)
+ return;
+
g_object_ref (object);
g_object_notify_by_spec_internal (object, pspec);
g_object_unref (object);
*
* Reverts the effect of a previous call to
* g_object_freeze_notify(). The freeze count is decreased on @object
- * and when it reaches zero, all queued "notify" signals are emitted.
+ * and when it reaches zero, queued "notify" signals are emitted.
+ *
+ * Duplicate notifications for each property are squashed so that at most one
+ * #GObject::notify signal is emitted for each property, in the reverse order
+ * in which they have been queued.
*
* It is an error to call this function when the freeze count is zero.
*/
g_object_unref (object);
}
+static void
+consider_issuing_property_deprecation_warning (const GParamSpec *pspec)
+{
+ static GHashTable *already_warned_table;
+ static const gchar *enable_diagnostic;
+ static GMutex already_warned_lock;
+ gboolean already;
+
+ if (!(pspec->flags & G_PARAM_DEPRECATED))
+ return;
+
+ if (g_once_init_enter (&enable_diagnostic))
+ {
+ const gchar *value = g_getenv ("G_ENABLE_DIAGNOSTIC");
+
+ if (!value)
+ value = "-";
+
+ g_once_init_leave (&enable_diagnostic, value);
+ }
+
+ if (enable_diagnostic[0] == '0')
+ return;
+
+ /* We hash only on property names: this means that we could end up in
+ * a situation where we fail to emit a warning about a pair of
+ * same-named deprecated properties used on two separate types.
+ * That's pretty unlikely to occur, and even if it does, you'll still
+ * have seen the warning for the first one...
+ *
+ * Doing it this way lets us hash directly on the (interned) property
+ * name pointers.
+ */
+ g_mutex_lock (&already_warned_lock);
+
+ if (already_warned_table == NULL)
+ already_warned_table = g_hash_table_new (NULL, NULL);
+
+ already = g_hash_table_contains (already_warned_table, (gpointer) pspec->name);
+ if (!already)
+ g_hash_table_add (already_warned_table, (gpointer) pspec->name);
+
+ g_mutex_unlock (&already_warned_lock);
+
+ if (!already)
+ g_warning ("The property %s:%s is deprecated and shouldn't be used "
+ "anymore. It will be removed in a future version.",
+ g_type_name (pspec->owner_type), pspec->name);
+}
+
static inline void
object_get_property (GObject *object,
GParamSpec *pspec,
redirect = g_param_spec_get_redirect_target (pspec);
if (redirect)
- pspec = redirect;
-
+ pspec = redirect;
+
+ consider_issuing_property_deprecation_warning (pspec);
+
class->get_property (object, param_id, value, pspec);
}
GObjectClass *class = g_type_class_peek (pspec->owner_type);
guint param_id = PARAM_SPEC_PARAM_ID (pspec);
GParamSpec *redirect;
- static const gchar * enable_diagnostic = NULL;
if (class == NULL)
{
if (redirect)
pspec = redirect;
- if (G_UNLIKELY (!enable_diagnostic))
- {
- enable_diagnostic = g_getenv ("G_ENABLE_DIAGNOSTIC");
- if (!enable_diagnostic)
- enable_diagnostic = "0";
- }
-
- if (enable_diagnostic[0] == '1')
- {
- if (pspec->flags & G_PARAM_DEPRECATED)
- g_warning ("The property %s:%s is deprecated and shouldn't be used "
- "anymore. It will be removed in a future version.",
- G_OBJECT_TYPE_NAME (object), pspec->name);
- }
-
/* provide a copy to work from, convert (if necessary) and validate */
g_value_init (&tmp_value, pspec->value_type);
if (!g_value_transform (value, &tmp_value))
- g_warning ("unable to set property `%s' of type `%s' from value of type `%s'",
+ g_warning ("unable to set property '%s' of type '%s' from value of type '%s'",
pspec->name,
g_type_name (pspec->value_type),
G_VALUE_TYPE_NAME (value));
{
gchar *contents = g_strdup_value_contents (value);
- g_warning ("value \"%s\" of type `%s' is invalid or out of range for property `%s' of type `%s'",
+ g_warning ("value \"%s\" of type '%s' is invalid or out of range for property '%s' of type '%s'",
contents,
G_VALUE_TYPE_NAME (value),
pspec->name,
}
else
{
- GParamSpec *notify_pspec;
-
class->set_property (object, param_id, &tmp_value, pspec);
- notify_pspec = get_notify_pspec (pspec);
+ if (~pspec->flags & G_PARAM_EXPLICIT_NOTIFY)
+ {
+ GParamSpec *notify_pspec;
+
+ notify_pspec = get_notify_pspec (pspec);
- if (notify_pspec != NULL)
- g_object_notify_queue_add (object, nqueue, notify_pspec);
+ if (notify_pspec != NULL)
+ g_object_notify_queue_add (object, nqueue, notify_pspec);
+ }
}
g_value_unset (&tmp_value);
}
static void
-object_interface_check_properties (gpointer func_data,
+object_interface_check_properties (gpointer check_data,
gpointer g_iface)
{
GTypeInterface *iface_class = g_iface;
class = g_type_class_ref (iface_class->g_instance_type);
- if (!G_IS_OBJECT_CLASS (class))
+ if (class == NULL)
return;
+ if (!G_IS_OBJECT_CLASS (class))
+ goto out;
+
pspecs = g_param_spec_pool_list (pspec_pool, iface_type, &n);
while (n--)
continue;
}
- /* The implementation paramspec must have a less restrictive
- * type than the interface parameter spec for set() and a
- * more restrictive type for get(). We just require equality,
- * rather than doing something more complicated checking
- * the READABLE and WRITABLE flags. We also simplify here
- * by only checking the value type, not the G_PARAM_SPEC_TYPE.
+ /* We do a number of checks on the properties of an interface to
+ * make sure that all classes implementing the interface are
+ * overriding the properties in a sane way.
+ *
+ * We do the checks in order of importance so that we can give
+ * more useful error messages first.
+ *
+ * First, we check that the implementation doesn't remove the
+ * basic functionality (readability, writability) advertised by
+ * the interface. Next, we check that it doesn't introduce
+ * additional restrictions (such as construct-only). Finally, we
+ * make sure the types are compatible.
*/
- if (class_pspec &&
- !g_type_is_a (pspecs[n]->value_type,
- class_pspec->value_type))
- {
- g_critical ("Property '%s' on class '%s' has type '%s' "
- "which is different from the type '%s', "
- "of the property on interface '%s'\n",
- pspecs[n]->name,
- g_type_name (G_OBJECT_CLASS_TYPE (class)),
- g_type_name (G_PARAM_SPEC_VALUE_TYPE (class_pspec)),
- g_type_name (G_PARAM_SPEC_VALUE_TYPE (pspecs[n])),
- g_type_name (iface_type));
- }
#define SUBSET(a,b,mask) (((a) & ~(b) & (mask)) == 0)
+ /* If the property on the interface is readable then the
+ * implementation must be readable. If the interface is writable
+ * then the implementation must be writable.
+ */
+ if (!SUBSET (pspecs[n]->flags, class_pspec->flags, G_PARAM_READABLE | G_PARAM_WRITABLE))
+ {
+ g_critical ("Flags for property '%s' on class '%s' remove functionality compared with the "
+ "property on interface '%s'\n", pspecs[n]->name,
+ g_type_name (G_OBJECT_CLASS_TYPE (class)), g_type_name (iface_type));
+ continue;
+ }
- /* CONSTRUCT and CONSTRUCT_ONLY add restrictions.
- * READABLE and WRITABLE remove restrictions. The implementation
- * paramspec must have less restrictive flags.
+ /* If the property on the interface is writable then we need to
+ * make sure the implementation doesn't introduce new restrictions
+ * on that writability (ie: construct-only).
+ *
+ * If the interface was not writable to begin with then we don't
+ * really have any problems here because "writable at construct
+ * type only" is still more permissive than "read only".
*/
- if (class_pspec &&
- (!SUBSET (class_pspec->flags,
- pspecs[n]->flags,
- G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY) ||
- !SUBSET (pspecs[n]->flags,
- class_pspec->flags,
- G_PARAM_READABLE | G_PARAM_WRITABLE)))
- {
- g_critical ("Flags for property '%s' on class '%s' "
- "are not compatible with the property on"
- "interface '%s'\n",
- pspecs[n]->name,
- g_type_name (G_OBJECT_CLASS_TYPE (class)),
- g_type_name (iface_type));
- }
+ if (pspecs[n]->flags & G_PARAM_WRITABLE)
+ {
+ if (!SUBSET (class_pspec->flags, pspecs[n]->flags, G_PARAM_CONSTRUCT_ONLY))
+ {
+ g_critical ("Flags for property '%s' on class '%s' introduce additional restrictions on "
+ "writability compared with the property on interface '%s'\n", pspecs[n]->name,
+ g_type_name (G_OBJECT_CLASS_TYPE (class)), g_type_name (iface_type));
+ continue;
+ }
+ }
#undef SUBSET
+
+ /* If the property on the interface is readable then we are
+ * effectively advertising that reading the property will return a
+ * value of a specific type. All implementations of the interface
+ * need to return items of this type -- but may be more
+ * restrictive. For example, it is legal to have:
+ *
+ * GtkWidget *get_item();
+ *
+ * that is implemented by a function that always returns a
+ * GtkEntry. In short: readability implies that the
+ * implementation value type must be equal or more restrictive.
+ *
+ * Similarly, if the property on the interface is writable then
+ * must be able to accept the property being set to any value of
+ * that type, including subclasses. In this case, we may also be
+ * less restrictive. For example, it is legal to have:
+ *
+ * set_item (GtkEntry *);
+ *
+ * that is implemented by a function that will actually work with
+ * any GtkWidget. In short: writability implies that the
+ * implementation value type must be equal or less restrictive.
+ *
+ * In the case that the property is both readable and writable
+ * then the only way that both of the above can be satisfied is
+ * with a type that is exactly equal.
+ */
+ switch (pspecs[n]->flags & (G_PARAM_READABLE | G_PARAM_WRITABLE))
+ {
+ case G_PARAM_READABLE | G_PARAM_WRITABLE:
+ /* class pspec value type must have exact equality with interface */
+ if (pspecs[n]->value_type != class_pspec->value_type)
+ g_critical ("Read/writable property '%s' on class '%s' has type '%s' which is not exactly equal to the "
+ "type '%s' of the property on the interface '%s'\n", pspecs[n]->name,
+ g_type_name (G_OBJECT_CLASS_TYPE (class)), g_type_name (G_PARAM_SPEC_VALUE_TYPE (class_pspec)),
+ g_type_name (G_PARAM_SPEC_VALUE_TYPE (pspecs[n])), g_type_name (iface_type));
+ break;
+
+ case G_PARAM_READABLE:
+ /* class pspec value type equal or more restrictive than interface */
+ if (!g_type_is_a (class_pspec->value_type, pspecs[n]->value_type))
+ g_critical ("Read-only property '%s' on class '%s' has type '%s' which is not equal to or more "
+ "restrictive than the type '%s' of the property on the interface '%s'\n", pspecs[n]->name,
+ g_type_name (G_OBJECT_CLASS_TYPE (class)), g_type_name (G_PARAM_SPEC_VALUE_TYPE (class_pspec)),
+ g_type_name (G_PARAM_SPEC_VALUE_TYPE (pspecs[n])), g_type_name (iface_type));
+ break;
+
+ case G_PARAM_WRITABLE:
+ /* class pspec value type equal or less restrictive than interface */
+ if (!g_type_is_a (pspecs[n]->value_type, class_pspec->value_type))
+ g_critical ("Write-only property '%s' on class '%s' has type '%s' which is not equal to or less "
+ "restrictive than the type '%s' of the property on the interface '%s' \n", pspecs[n]->name,
+ g_type_name (G_OBJECT_CLASS_TYPE (class)), g_type_name (G_PARAM_SPEC_VALUE_TYPE (class_pspec)),
+ g_type_name (G_PARAM_SPEC_VALUE_TYPE (pspecs[n])), g_type_name (iface_type));
+ break;
+
+ default:
+ g_assert_not_reached ();
+ }
}
g_free (pspecs);
+ out:
g_type_class_unref (class);
}
return object;
}
-static gboolean
-slist_maybe_remove (GSList **slist,
- gconstpointer data)
+static gpointer
+g_object_new_with_custom_constructor (GObjectClass *class,
+ GObjectConstructParam *params,
+ guint n_params)
{
- GSList *last = NULL, *node = *slist;
- while (node)
+ GObjectNotifyQueue *nqueue = NULL;
+ gboolean newly_constructed;
+ GObjectConstructParam *cparams;
+ GObject *object;
+ GValue *cvalues;
+ gint n_cparams;
+ gint cvals_used;
+ GSList *node;
+ gint i;
+
+ /* If we have ->constructed() then we have to do a lot more work.
+ * It's possible that this is a singleton and it's also possible
+ * that the user's constructor() will attempt to modify the values
+ * that we pass in, so we'll need to allocate copies of them.
+ * It's also possible that the user may attempt to call
+ * g_object_set() from inside of their constructor, so we need to
+ * add ourselves to a list of objects for which that is allowed
+ * while their constructor() is running.
+ */
+
+ /* Create the array of GObjectConstructParams for constructor() */
+ n_cparams = g_slist_length (class->construct_properties);
+ cparams = g_new (GObjectConstructParam, n_cparams);
+ cvalues = g_new0 (GValue, n_cparams);
+ cvals_used = 0;
+ i = 0;
+
+ /* As above, we may find the value in the passed-in params list.
+ *
+ * If we have the value passed in then we can use the GValue from
+ * it directly because it is safe to modify. If we use the
+ * default value from the class, we had better not pass that in
+ * and risk it being modified, so we create a new one.
+ * */
+ for (node = class->construct_properties; node; node = node->next)
{
- if (node->data == data)
+ GParamSpec *pspec;
+ GValue *value;
+ gint j;
+
+ pspec = node->data;
+ value = NULL; /* to silence gcc... */
+
+ for (j = 0; j < n_params; j++)
+ if (params[j].pspec == pspec)
+ {
+ consider_issuing_property_deprecation_warning (pspec);
+ value = params[j].value;
+ break;
+ }
+
+ if (j == n_params)
{
- if (last)
- last->next = node->next;
- else
- *slist = node->next;
- g_slist_free_1 (node);
- return TRUE;
+ value = &cvalues[cvals_used++];
+ g_value_init (value, pspec->value_type);
+ g_param_value_set_default (pspec, value);
}
- last = node;
- node = last->next;
+
+ cparams[i].pspec = pspec;
+ cparams[i].value = value;
+ i++;
}
- return FALSE;
+
+ /* construct object from construction parameters */
+ object = class->constructor (class->g_type_class.g_type, n_cparams, cparams);
+ /* free construction values */
+ g_free (cparams);
+ while (cvals_used--)
+ g_value_unset (&cvalues[cvals_used]);
+ g_free (cvalues);
+
+ /* There is code in the wild that relies on being able to return NULL
+ * from its custom constructor. This was never a supported operation,
+ * but since the code is already out there...
+ */
+ if (object == NULL)
+ {
+ g_critical ("Custom constructor for class %s returned NULL (which is invalid). "
+ "Please use GInitable instead.", G_OBJECT_CLASS_NAME (class));
+ return NULL;
+ }
+
+ /* g_object_init() will have marked the object as being in-construction.
+ * Check if the returned object still is so marked, or if this is an
+ * already-existing singleton (in which case we should not do 'constructed').
+ */
+ newly_constructed = object_in_construction (object);
+ if (newly_constructed)
+ g_datalist_id_set_data (&object->qdata, quark_in_construction, NULL);
+
+ if (CLASS_HAS_PROPS (class))
+ {
+ /* If this object was newly_constructed then g_object_init()
+ * froze the queue. We need to freeze it here in order to get
+ * the handle so that we can thaw it below (otherwise it will
+ * be frozen forever).
+ *
+ * We also want to do a freeze if we have any params to set,
+ * even on a non-newly_constructed object.
+ *
+ * It's possible that we have the case of non-newly created
+ * singleton and all of the passed-in params were construct
+ * properties so n_params > 0 but we will actually set no
+ * properties. This is a pretty lame case to optimise, so
+ * just ignore it and freeze anyway.
+ */
+ if (newly_constructed || n_params)
+ nqueue = g_object_notify_queue_freeze (object, FALSE);
+
+ /* Remember: if it was newly_constructed then g_object_init()
+ * already did a freeze, so we now have two. Release one.
+ */
+ if (newly_constructed)
+ g_object_notify_queue_thaw (object, nqueue);
+ }
+
+ /* run 'constructed' handler if there is a custom one */
+ if (newly_constructed && CLASS_HAS_CUSTOM_CONSTRUCTED (class))
+ class->constructed (object);
+
+ /* set remaining properties */
+ for (i = 0; i < n_params; i++)
+ if (!(params[i].pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY)))
+ {
+ consider_issuing_property_deprecation_warning (params[i].pspec);
+ object_set_property (object, params[i].pspec, params[i].value, nqueue);
+ }
+
+ /* If nqueue is non-NULL then we are frozen. Thaw it. */
+ if (nqueue)
+ g_object_notify_queue_thaw (object, nqueue);
+
+ return object;
}
-static inline gboolean
-object_in_construction_list (GObject *object)
+static gpointer
+g_object_new_internal (GObjectClass *class,
+ GObjectConstructParam *params,
+ guint n_params)
{
- gboolean in_construction;
- G_LOCK (construction_mutex);
- in_construction = g_slist_find (construction_objects, object) != NULL;
- G_UNLOCK (construction_mutex);
- return in_construction;
+ GObjectNotifyQueue *nqueue = NULL;
+ GObject *object;
+
+ if G_UNLIKELY (CLASS_HAS_CUSTOM_CONSTRUCTOR (class))
+ return g_object_new_with_custom_constructor (class, params, n_params);
+
+ object = (GObject *) g_type_create_instance (class->g_type_class.g_type);
+
+ if (CLASS_HAS_PROPS (class))
+ {
+ GSList *node;
+
+ /* This will have been setup in g_object_init() */
+ nqueue = g_datalist_id_get_data (&object->qdata, quark_notify_queue);
+ g_assert (nqueue != NULL);
+
+ /* We will set exactly n_construct_properties construct
+ * properties, but they may come from either the class default
+ * values or the passed-in parameter list.
+ */
+ for (node = class->construct_properties; node; node = node->next)
+ {
+ const GValue *value;
+ GParamSpec *pspec;
+ gint j;
+
+ pspec = node->data;
+ value = NULL; /* to silence gcc... */
+
+ for (j = 0; j < n_params; j++)
+ if (params[j].pspec == pspec)
+ {
+ consider_issuing_property_deprecation_warning (pspec);
+ value = params[j].value;
+ break;
+ }
+
+ if (j == n_params)
+ value = g_param_spec_get_default_value (pspec);
+
+ object_set_property (object, pspec, value, nqueue);
+ }
+ }
+
+ /* run 'constructed' handler if there is a custom one */
+ if (CLASS_HAS_CUSTOM_CONSTRUCTED (class))
+ class->constructed (object);
+
+ if (nqueue)
+ {
+ gint i;
+
+ /* Set remaining properties. The construct properties will
+ * already have been taken, so set only the non-construct
+ * ones.
+ */
+ for (i = 0; i < n_params; i++)
+ if (!(params[i].pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY)))
+ {
+ consider_issuing_property_deprecation_warning (params[i].pspec);
+ object_set_property (object, params[i].pspec, params[i].value, nqueue);
+ }
+
+ g_object_notify_queue_thaw (object, nqueue);
+ }
+
+ return object;
}
/**
*/
gpointer
g_object_newv (GType object_type,
- guint n_parameters,
- GParameter *parameters)
+ guint n_parameters,
+ GParameter *parameters)
{
- GObjectConstructParam *cparams = NULL, *oparams;
- GObjectNotifyQueue *nqueue = NULL; /* shouldn't be initialized, just to silence compiler */
- GObject *object;
GObjectClass *class, *unref_class = NULL;
- GSList *slist;
- guint n_total_cparams = 0, n_cparams = 0, n_oparams = 0, n_cvalues;
- GValue *cvalues;
- GList *clist = NULL;
- gboolean newly_constructed;
- guint i;
+ GObject *object;
g_return_val_if_fail (G_TYPE_IS_OBJECT (object_type), NULL);
+ g_return_val_if_fail (n_parameters == 0 || parameters != NULL, NULL);
+ /* Try to avoid thrashing the ref_count if we don't need to (since
+ * it's a locked operation).
+ */
class = g_type_class_peek_static (object_type);
+
if (!class)
class = unref_class = g_type_class_ref (object_type);
- for (slist = class->construct_properties; slist; slist = slist->next)
- {
- clist = g_list_prepend (clist, slist->data);
- n_total_cparams += 1;
- }
- if (n_parameters == 0 && n_total_cparams == 0)
+ if (n_parameters)
{
- /* This is a simple object with no construct properties, and
- * no properties are being set, so short circuit the parameter
- * handling. This speeds up simple object construction.
- */
- oparams = NULL;
- object = class->constructor (object_type, 0, NULL);
- goto did_construction;
- }
+ GObjectConstructParam *cparams;
+ guint i, j;
- /* collect parameters, sort into construction and normal ones */
- oparams = g_new (GObjectConstructParam, n_parameters);
- cparams = g_new (GObjectConstructParam, n_total_cparams);
- for (i = 0; i < n_parameters; i++)
- {
- GValue *value = ¶meters[i].value;
- GParamSpec *pspec = g_param_spec_pool_lookup (pspec_pool,
- parameters[i].name,
- object_type,
- TRUE);
- if (!pspec)
- {
- g_warning ("%s: object class `%s' has no property named `%s'",
- G_STRFUNC,
- g_type_name (object_type),
- parameters[i].name);
- continue;
- }
- if (!(pspec->flags & G_PARAM_WRITABLE))
- {
- g_warning ("%s: property `%s' of object class `%s' is not writable",
- G_STRFUNC,
- pspec->name,
- g_type_name (object_type));
- continue;
- }
- if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))
- {
- GList *list = g_list_find (clist, pspec);
+ cparams = g_newa (GObjectConstructParam, n_parameters);
+ j = 0;
- if (!list)
- {
- g_warning ("%s: construct property \"%s\" for object `%s' can't be set twice",
- G_STRFUNC, pspec->name, g_type_name (object_type));
- continue;
- }
- cparams[n_cparams].pspec = pspec;
- cparams[n_cparams].value = value;
- n_cparams++;
- if (!list->prev)
- clist = list->next;
- else
- list->prev->next = list->next;
- if (list->next)
- list->next->prev = list->prev;
- g_list_free_1 (list);
- }
- else
- {
- oparams[n_oparams].pspec = pspec;
- oparams[n_oparams].value = value;
- n_oparams++;
- }
- }
-
- /* set remaining construction properties to default values */
- n_cvalues = n_total_cparams - n_cparams;
- cvalues = g_new (GValue, n_cvalues);
- while (clist)
- {
- GList *tmp = clist->next;
- GParamSpec *pspec = clist->data;
- GValue *value = cvalues + n_total_cparams - n_cparams - 1;
-
- value->g_type = 0;
- g_value_init (value, pspec->value_type);
- g_param_value_set_default (pspec, value);
-
- cparams[n_cparams].pspec = pspec;
- cparams[n_cparams].value = value;
- n_cparams++;
-
- g_list_free_1 (clist);
- clist = tmp;
- }
-
- /* construct object from construction parameters */
- object = class->constructor (object_type, n_total_cparams, cparams);
- /* free construction values */
- g_free (cparams);
- while (n_cvalues--)
- g_value_unset (cvalues + n_cvalues);
- g_free (cvalues);
+ for (i = 0; i < n_parameters; i++)
+ {
+ GParamSpec *pspec;
+ gint k;
+
+ pspec = g_param_spec_pool_lookup (pspec_pool, parameters[i].name, object_type, TRUE);
+
+ if G_UNLIKELY (!pspec)
+ {
+ g_critical ("%s: object class '%s' has no property named '%s'",
+ G_STRFUNC, g_type_name (object_type), parameters[i].name);
+ continue;
+ }
+
+ if G_UNLIKELY (~pspec->flags & G_PARAM_WRITABLE)
+ {
+ g_critical ("%s: property '%s' of object class '%s' is not writable",
+ G_STRFUNC, pspec->name, g_type_name (object_type));
+ continue;
+ }
+
+ if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))
+ {
+ for (k = 0; k < j; k++)
+ if (cparams[k].pspec == pspec)
+ break;
+ if G_UNLIKELY (k != j)
+ {
+ g_critical ("%s: construct property '%s' for type '%s' cannot be set twice",
+ G_STRFUNC, parameters[i].name, g_type_name (object_type));
+ continue;
+ }
+ }
+
+ cparams[j].pspec = pspec;
+ cparams[j].value = ¶meters[i].value;
+ j++;
+ }
- did_construction:
- if (CLASS_HAS_CUSTOM_CONSTRUCTOR (class))
- {
- /* adjust freeze_count according to g_object_init() and remaining properties */
- G_LOCK (construction_mutex);
- newly_constructed = slist_maybe_remove (&construction_objects, object);
- G_UNLOCK (construction_mutex);
+ object = g_object_new_internal (class, cparams, j);
}
else
- newly_constructed = TRUE;
-
- if (CLASS_HAS_PROPS (class))
- {
- if (newly_constructed || n_oparams)
- nqueue = g_object_notify_queue_freeze (object, FALSE);
- if (newly_constructed)
- g_object_notify_queue_thaw (object, nqueue);
- }
-
- /* run 'constructed' handler if there is a custom one */
- if (newly_constructed && CLASS_HAS_CUSTOM_CONSTRUCTED (class))
- class->constructed (object);
-
- /* set remaining properties */
- for (i = 0; i < n_oparams; i++)
- object_set_property (object, oparams[i].pspec, oparams[i].value, nqueue);
- g_free (oparams);
-
- if (CLASS_HAS_PROPS (class))
- {
- /* release our own freeze count and handle notifications */
- if (newly_constructed || n_oparams)
- g_object_notify_queue_thaw (object, nqueue);
- }
+ /* Fast case: no properties passed in. */
+ object = g_object_new_internal (class, NULL, 0);
if (unref_class)
g_type_class_unref (unref_class);
* Returns: a new instance of @object_type
*/
GObject*
-g_object_new_valist (GType object_type,
- const gchar *first_property_name,
- va_list var_args)
+g_object_new_valist (GType object_type,
+ const gchar *first_property_name,
+ va_list var_args)
{
- GObjectClass *class;
- GParameter *params;
- const gchar *name;
+ GObjectClass *class, *unref_class = NULL;
GObject *object;
- guint n_params = 0, n_alloced_params = 16;
-
+
g_return_val_if_fail (G_TYPE_IS_OBJECT (object_type), NULL);
- if (!first_property_name)
- return g_object_newv (object_type, 0, NULL);
+ /* Try to avoid thrashing the ref_count if we don't need to (since
+ * it's a locked operation).
+ */
+ class = g_type_class_peek_static (object_type);
- class = g_type_class_ref (object_type);
+ if (!class)
+ class = unref_class = g_type_class_ref (object_type);
- params = g_new0 (GParameter, n_alloced_params);
- name = first_property_name;
- while (name)
+ if (first_property_name)
{
- gchar *error = NULL;
- GParamSpec *pspec = g_param_spec_pool_lookup (pspec_pool,
- name,
- object_type,
- TRUE);
- if (!pspec)
- {
- g_warning ("%s: object class `%s' has no property named `%s'",
- G_STRFUNC,
- g_type_name (object_type),
- name);
- break;
- }
- if (n_params >= n_alloced_params)
- {
- n_alloced_params += 16;
- params = g_renew (GParameter, params, n_alloced_params);
- memset (params + n_params, 0, 16 * (sizeof *params));
- }
- params[n_params].name = name;
- G_VALUE_COLLECT_INIT (¶ms[n_params].value, pspec->value_type,
- var_args, 0, &error);
- if (error)
- {
- g_warning ("%s: %s", G_STRFUNC, error);
- g_free (error);
- g_value_unset (¶ms[n_params].value);
- break;
- }
- n_params++;
- name = va_arg (var_args, gchar*);
- }
+ GObjectConstructParam stack_params[16];
+ GObjectConstructParam *params;
+ const gchar *name;
+ gint n_params = 0;
- object = g_object_newv (object_type, n_params, params);
+ name = first_property_name;
+ params = stack_params;
- while (n_params--)
- g_value_unset (¶ms[n_params].value);
- g_free (params);
+ do
+ {
+ gchar *error = NULL;
+ GParamSpec *pspec;
+ gint i;
+
+ pspec = g_param_spec_pool_lookup (pspec_pool, name, object_type, TRUE);
+
+ if G_UNLIKELY (!pspec)
+ {
+ g_critical ("%s: object class '%s' has no property named '%s'",
+ G_STRFUNC, g_type_name (object_type), name);
+ /* Can't continue because arg list will be out of sync. */
+ break;
+ }
+
+ if G_UNLIKELY (~pspec->flags & G_PARAM_WRITABLE)
+ {
+ g_critical ("%s: property '%s' of object class '%s' is not writable",
+ G_STRFUNC, pspec->name, g_type_name (object_type));
+ break;
+ }
+
+ if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))
+ {
+ for (i = 0; i < n_params; i++)
+ if (params[i].pspec == pspec)
+ break;
+ if G_UNLIKELY (i != n_params)
+ {
+ g_critical ("%s: property '%s' for type '%s' cannot be set twice",
+ G_STRFUNC, name, g_type_name (object_type));
+ break;
+ }
+ }
+
+ if (n_params == 16)
+ {
+ params = g_new (GObjectConstructParam, n_params + 1);
+ memcpy (params, stack_params, sizeof stack_params);
+ }
+ else if (n_params > 16)
+ params = g_renew (GObjectConstructParam, params, n_params + 1);
+
+ params[n_params].pspec = pspec;
+ params[n_params].value = g_newa (GValue, 1);
+ memset (params[n_params].value, 0, sizeof (GValue));
+
+ G_VALUE_COLLECT_INIT (params[n_params].value, pspec->value_type, var_args, 0, &error);
+
+ if (error)
+ {
+ g_critical ("%s: %s", G_STRFUNC, error);
+ g_value_unset (params[n_params].value);
+ g_free (error);
+ break;
+ }
+
+ n_params++;
+ }
+ while ((name = va_arg (var_args, const gchar *)));
- g_type_class_unref (class);
+ object = g_object_new_internal (class, params, n_params);
+
+ while (n_params--)
+ g_value_unset (params[n_params].value);
+
+ if (params != stack_params)
+ g_free (params);
+ }
+ else
+ /* Fast case: no properties passed in. */
+ object = g_object_new_internal (class, NULL, 0);
+
+ if (unref_class)
+ g_type_class_unref (unref_class);
return object;
}
TRUE);
if (!pspec)
{
- g_warning ("%s: object class `%s' has no property named `%s'",
+ g_warning ("%s: object class '%s' has no property named '%s'",
G_STRFUNC,
G_OBJECT_TYPE_NAME (object),
name);
}
if (!(pspec->flags & G_PARAM_WRITABLE))
{
- g_warning ("%s: property `%s' of object class `%s' is not writable",
+ g_warning ("%s: property '%s' of object class '%s' is not writable",
G_STRFUNC,
pspec->name,
G_OBJECT_TYPE_NAME (object));
break;
}
- if ((pspec->flags & G_PARAM_CONSTRUCT_ONLY) && !object_in_construction_list (object))
+ if ((pspec->flags & G_PARAM_CONSTRUCT_ONLY) && !object_in_construction (object))
{
- g_warning ("%s: construct property \"%s\" for object `%s' can't be set after construction",
+ g_warning ("%s: construct property \"%s\" for object '%s' can't be set after construction",
G_STRFUNC, pspec->name, G_OBJECT_TYPE_NAME (object));
break;
}
g_value_unset (&value);
break;
}
-
+
+ consider_issuing_property_deprecation_warning (pspec);
object_set_property (object, pspec, &value, nqueue);
g_value_unset (&value);
-
+
name = va_arg (var_args, gchar*);
}
TRUE);
if (!pspec)
{
- g_warning ("%s: object class `%s' has no property named `%s'",
+ g_warning ("%s: object class '%s' has no property named '%s'",
G_STRFUNC,
G_OBJECT_TYPE_NAME (object),
name);
}
if (!(pspec->flags & G_PARAM_READABLE))
{
- g_warning ("%s: property `%s' of object class `%s' is not readable",
+ g_warning ("%s: property '%s' of object class '%s' is not readable",
G_STRFUNC,
pspec->name,
G_OBJECT_TYPE_NAME (object));
* name/value pairs, followed by %NULL
*
* Sets properties on an object.
+ *
+ * Note that the "notify" signals are queued and only emitted (in
+ * reverse order) after all properties have been set. See
+ * g_object_freeze_notify().
*/
void
g_object_set (gpointer _object,
* is responsible for freeing the memory in the appropriate manner for
* the type, for instance by calling g_free() or g_object_unref().
*
- * <example>
- * <title>Using g_object_get(<!-- -->)</title>
- * An example of using g_object_get() to get the contents
- * of three properties - one of type #G_TYPE_INT,
- * one of type #G_TYPE_STRING, and one of type #G_TYPE_OBJECT:
- * <programlisting>
+ * Here is an example of using g_object_get() to get the contents
+ * of three properties: an integer, a string and an object:
+ * |[<!-- language="C" -->
* gint intval;
* gchar *strval;
* GObject *objval;
*
* g_free (strval);
* g_object_unref (objval);
- * </programlisting>
- * </example>
+ * ]|
*/
void
g_object_get (gpointer _object,
G_OBJECT_TYPE (object),
TRUE);
if (!pspec)
- g_warning ("%s: object class `%s' has no property named `%s'",
+ g_warning ("%s: object class '%s' has no property named '%s'",
G_STRFUNC,
G_OBJECT_TYPE_NAME (object),
property_name);
else if (!(pspec->flags & G_PARAM_WRITABLE))
- g_warning ("%s: property `%s' of object class `%s' is not writable",
+ g_warning ("%s: property '%s' of object class '%s' is not writable",
G_STRFUNC,
pspec->name,
G_OBJECT_TYPE_NAME (object));
- else if ((pspec->flags & G_PARAM_CONSTRUCT_ONLY) && !object_in_construction_list (object))
- g_warning ("%s: construct property \"%s\" for object `%s' can't be set after construction",
+ else if ((pspec->flags & G_PARAM_CONSTRUCT_ONLY) && !object_in_construction (object))
+ g_warning ("%s: construct property \"%s\" for object '%s' can't be set after construction",
G_STRFUNC, pspec->name, G_OBJECT_TYPE_NAME (object));
else
- object_set_property (object, pspec, value, nqueue);
-
+ {
+ consider_issuing_property_deprecation_warning (pspec);
+ object_set_property (object, pspec, value, nqueue);
+ }
+
g_object_notify_queue_thaw (object, nqueue);
g_object_unref (object);
}
G_OBJECT_TYPE (object),
TRUE);
if (!pspec)
- g_warning ("%s: object class `%s' has no property named `%s'",
+ g_warning ("%s: object class '%s' has no property named '%s'",
G_STRFUNC,
G_OBJECT_TYPE_NAME (object),
property_name);
else if (!(pspec->flags & G_PARAM_READABLE))
- g_warning ("%s: property `%s' of object class `%s' is not readable",
+ g_warning ("%s: property '%s' of object class '%s' is not readable",
G_STRFUNC,
pspec->name,
G_OBJECT_TYPE_NAME (object));
}
else if (!g_value_type_transformable (pspec->value_type, G_VALUE_TYPE (value)))
{
- g_warning ("%s: can't retrieve property `%s' of type `%s' as value of type `%s'",
+ g_warning ("%s: can't retrieve property '%s' of type '%s' as value of type '%s'",
G_STRFUNC, pspec->name,
g_type_name (pspec->value_type),
G_VALUE_TYPE_NAME (value));
*
* The signal specs expected by this function have the form
* "modifier::signal_name", where modifier can be one of the following:
- * <variablelist>
- * <varlistentry>
- * <term>signal</term>
- * <listitem><para>
- * equivalent to <literal>g_signal_connect_data (..., NULL, 0)</literal>
- * </para></listitem>
- * </varlistentry>
- * <varlistentry>
- * <term>object_signal</term>
- * <term>object-signal</term>
- * <listitem><para>
- * equivalent to <literal>g_signal_connect_object (..., 0)</literal>
- * </para></listitem>
- * </varlistentry>
- * <varlistentry>
- * <term>swapped_signal</term>
- * <term>swapped-signal</term>
- * <listitem><para>
- * equivalent to <literal>g_signal_connect_data (..., NULL, G_CONNECT_SWAPPED)</literal>
- * </para></listitem>
- * </varlistentry>
- * <varlistentry>
- * <term>swapped_object_signal</term>
- * <term>swapped-object-signal</term>
- * <listitem><para>
- * equivalent to <literal>g_signal_connect_object (..., G_CONNECT_SWAPPED)</literal>
- * </para></listitem>
- * </varlistentry>
- * <varlistentry>
- * <term>signal_after</term>
- * <term>signal-after</term>
- * <listitem><para>
- * equivalent to <literal>g_signal_connect_data (..., NULL, G_CONNECT_AFTER)</literal>
- * </para></listitem>
- * </varlistentry>
- * <varlistentry>
- * <term>object_signal_after</term>
- * <term>object-signal-after</term>
- * <listitem><para>
- * equivalent to <literal>g_signal_connect_object (..., G_CONNECT_AFTER)</literal>
- * </para></listitem>
- * </varlistentry>
- * <varlistentry>
- * <term>swapped_signal_after</term>
- * <term>swapped-signal-after</term>
- * <listitem><para>
- * equivalent to <literal>g_signal_connect_data (..., NULL, G_CONNECT_SWAPPED | G_CONNECT_AFTER)</literal>
- * </para></listitem>
- * </varlistentry>
- * <varlistentry>
- * <term>swapped_object_signal_after</term>
- * <term>swapped-object-signal-after</term>
- * <listitem><para>
- * equivalent to <literal>g_signal_connect_object (..., G_CONNECT_SWAPPED | G_CONNECT_AFTER)</literal>
- * </para></listitem>
- * </varlistentry>
- * </variablelist>
- *
- * |[
+ * * - signal: equivalent to g_signal_connect_data (..., NULL, 0)
+ * - object-signal, object_signal: equivalent to g_signal_connect_object (..., 0)
+ * - swapped-signal, swapped_signal: equivalent to g_signal_connect_data (..., NULL, G_CONNECT_SWAPPED)
+ * - swapped_object_signal, swapped-object-signal: equivalent to g_signal_connect_object (..., G_CONNECT_SWAPPED)
+ * - signal_after, signal-after: equivalent to g_signal_connect_data (..., NULL, G_CONNECT_AFTER)
+ * - object_signal_after, object-signal-after: equivalent to g_signal_connect_object (..., G_CONNECT_AFTER)
+ * - swapped_signal_after, swapped-signal-after: equivalent to g_signal_connect_data (..., NULL, G_CONNECT_SWAPPED | G_CONNECT_AFTER)
+ * - swapped_object_signal_after, swapped-object-signal-after: equivalent to g_signal_connect_object (..., G_CONNECT_SWAPPED | G_CONNECT_AFTER)
+ *
+ * |[<!-- language="C" -->
* menu->toplevel = g_object_connect (g_object_new (GTK_TYPE_WINDOW,
* "type", GTK_WINDOW_POPUP,
* "child", menu,
* NULL),
* "signal::event", gtk_menu_window_event, menu,
* "signal::size_request", gtk_menu_window_size_request, menu,
- * "signal::destroy", gtk_widget_destroyed, &menu->toplevel,
+ * "signal::destroy", gtk_widget_destroyed, &menu->toplevel,
* NULL);
* ]|
*
* "weak references" because they allow you to safely hold a pointer
* to an object without calling g_object_ref() (g_object_ref() adds a
* strong reference, that is, forces the object to stay alive).
+ *
+ * Note that the weak references created by this method are not
+ * thread-safe: they cannot safely be used in one thread if the
+ * object's last g_object_unref() might happen in another thread.
+ * Use #GWeakRef if thread-safety is required.
*/
void
g_object_weak_ref (GObject *object,
* the pointer located at @weak_pointer_location is only valid during
* the lifetime of @object. When the @object is finalized,
* @weak_pointer will be set to %NULL.
+ *
+ * Note that as with g_object_weak_ref(), the weak references created by
+ * this method are not thread-safe: they cannot safely be used in one
+ * thread if the object's last g_object_unref() might happen in another
+ * thread. Use #GWeakRef if thread-safety is required.
*/
void
g_object_add_weak_pointer (GObject *object,
* g_object_is_floating:
* @object: (type GObject.Object): a #GObject
*
- * Checks whether @object has a <link linkend="floating-ref">floating</link>
- * reference.
+ * Checks whether @object has a [floating][floating-ref] reference.
*
* Since: 2.10
*
* @object: (type GObject.Object): a #GObject
*
* Increase the reference count of @object, and possibly remove the
- * <link linkend="floating-ref">floating</link> reference, if @object
- * has a floating reference.
+ * [floating][floating-ref] reference, if @object has a floating reference.
*
* In other words, if the object is floating, then this call "assumes
* ownership" of the floating reference, converting it to a normal
* g_object_force_floating:
* @object: a #GObject
*
- * This function is intended for #GObject implementations to re-enforce a
- * <link linkend="floating-ref">floating</link> object reference.
- * Doing this is seldom required: all
- * #GInitiallyUnowned<!-- -->s are created with a floating reference which
- * usually just needs to be sunken by calling g_object_ref_sink().
+ * This function is intended for #GObject implementations to re-enforce
+ * a [floating][floating-ref] object reference. Doing this is seldom
+ * required: all #GInitiallyUnowneds are created with a floating reference
+ * which usually just needs to be sunken by calling g_object_ref_sink().
*
* Since: 2.10
*/
* to the proxy object, but when there are other references held to
* @object, a strong reference is held. The @notify callback is called
* when the reference from @object to the proxy object should be
- * <firstterm>toggled</firstterm> from strong to weak (@is_last_ref
- * true) or weak to strong (@is_last_ref false).
+ * "toggled" from strong to weak (@is_last_ref true) or weak to strong
+ * (@is_last_ref false).
*
* Since a (normal) reference must be held to the object before
* calling g_object_add_toggle_ref(), the initial state of the reverse
g_return_val_if_fail (G_IS_OBJECT (object), NULL);
g_return_val_if_fail (object->ref_count > 0, NULL);
-#ifdef G_ENABLE_DEBUG
- if (g_trap_object_ref == object)
- G_BREAKPOINT ();
-#endif /* G_ENABLE_DEBUG */
-
-
old_val = g_atomic_int_add (&object->ref_count, 1);
if (old_val == 1 && OBJECT_HAS_TOGGLE_REF (object))
g_return_if_fail (G_IS_OBJECT (object));
g_return_if_fail (object->ref_count > 0);
-#ifdef G_ENABLE_DEBUG
- if (g_trap_object_ref == object)
- G_BREAKPOINT ();
-#endif /* G_ENABLE_DEBUG */
-
/* here we want to atomically do: if (ref_count>1) { ref_count--; return; } */
retry_atomic_decrement1:
old_ref = g_atomic_int_get (&object->ref_count);
}
else
{
- /* we are about tp remove the last reference */
+ GSList **weak_locations;
+
+ /* The only way that this object can live at this point is if
+ * there are outstanding weak references already established
+ * before we got here.
+ *
+ * If there were not already weak references then no more can be
+ * established at this time, because the other thread would have
+ * to hold a strong ref in order to call
+ * g_object_add_weak_pointer() and then we wouldn't be here.
+ */
+ weak_locations = g_datalist_id_get_data (&object->qdata, quark_weak_locations);
+
+ if (weak_locations != NULL)
+ {
+ g_rw_lock_writer_lock (&weak_locations_lock);
+
+ /* It is possible that one of the weak references beat us to
+ * the lock. Make sure the refcount is still what we expected
+ * it to be.
+ */
+ old_ref = g_atomic_int_get (&object->ref_count);
+ if (old_ref != 1)
+ {
+ g_rw_lock_writer_unlock (&weak_locations_lock);
+ goto retry_atomic_decrement1;
+ }
+
+ /* We got the lock first, so the object will definitely die
+ * now. Clear out all the weak references.
+ */
+ while (*weak_locations)
+ {
+ GWeakRef *weak_ref_location = (*weak_locations)->data;
+
+ weak_ref_location->priv.p = NULL;
+ *weak_locations = g_slist_delete_link (*weak_locations, *weak_locations);
+ }
+
+ g_rw_lock_writer_unlock (&weak_locations_lock);
+ }
+
+ /* we are about to remove the last reference */
TRACE (GOBJECT_OBJECT_DISPOSE(object,G_TYPE_FROM_INSTANCE(object), 1));
G_OBJECT_GET_CLASS (object)->dispose (object);
TRACE (GOBJECT_OBJECT_DISPOSE_END(object,G_TYPE_FROM_INSTANCE(object), 1));
* Otherwise, the reference count of the object is decreased and the
* pointer is set to %NULL.
*
- * This function is threadsafe and modifies the pointer atomically,
- * using memory barriers where needed.
- *
* A macro is also included that allows this function to be used without
* pointer casts.
*
void
g_clear_object (volatile GObject **object_ptr)
{
- gpointer *ptr = (gpointer) object_ptr;
- gpointer old;
-
- /* This is a little frustrating.
- * Would be nice to have an atomic exchange (with no compare).
- */
- do
- old = g_atomic_pointer_get (ptr);
- while G_UNLIKELY (!g_atomic_pointer_compare_and_exchange (ptr, old, NULL));
-
- if (old)
- g_object_unref (old);
+ g_clear_pointer (object_ptr, g_object_unref);
}
/**
{
g_return_if_fail (G_IS_OBJECT (object));
g_return_if_fail (quark > 0);
-
+
g_datalist_id_set_data (&object->qdata, quark, data);
}
/**
+ * g_object_dup_qdata:
+ * @object: the #GObject to store user data on
+ * @quark: a #GQuark, naming the user data pointer
+ * @dup_func: (allow-none): function to dup the value
+ * @user_data: (allow-none): passed as user_data to @dup_func
+ *
+ * This is a variant of g_object_get_qdata() which returns
+ * a 'duplicate' of the value. @dup_func defines the
+ * meaning of 'duplicate' in this context, it could e.g.
+ * take a reference on a ref-counted object.
+ *
+ * If the @quark is not set on the object then @dup_func
+ * will be called with a %NULL argument.
+ *
+ * Note that @dup_func is called while user data of @object
+ * is locked.
+ *
+ * This function can be useful to avoid races when multiple
+ * threads are using object data on the same key on the same
+ * object.
+ *
+ * Returns: the result of calling @dup_func on the value
+ * associated with @quark on @object, or %NULL if not set.
+ * If @dup_func is %NULL, the value is returned
+ * unmodified.
+ *
+ * Since: 2.34
+ */
+gpointer
+g_object_dup_qdata (GObject *object,
+ GQuark quark,
+ GDuplicateFunc dup_func,
+ gpointer user_data)
+{
+ g_return_val_if_fail (G_IS_OBJECT (object), NULL);
+ g_return_val_if_fail (quark > 0, NULL);
+
+ return g_datalist_id_dup_data (&object->qdata, quark, dup_func, user_data);
+}
+
+/**
+ * g_object_replace_qdata:
+ * @object: the #GObject to store user data on
+ * @quark: a #GQuark, naming the user data pointer
+ * @oldval: (allow-none): the old value to compare against
+ * @newval: (allow-none): the new value
+ * @destroy: (allow-none): a destroy notify for the new value
+ * @old_destroy: (allow-none): destroy notify for the existing value
+ *
+ * Compares the user data for the key @quark on @object with
+ * @oldval, and if they are the same, replaces @oldval with
+ * @newval.
+ *
+ * This is like a typical atomic compare-and-exchange
+ * operation, for user data on an object.
+ *
+ * If the previous value was replaced then ownership of the
+ * old value (@oldval) is passed to the caller, including
+ * the registered destroy notify for it (passed out in @old_destroy).
+ * Its up to the caller to free this as he wishes, which may
+ * or may not include using @old_destroy as sometimes replacement
+ * should not destroy the object in the normal way.
+ *
+ * Returns: %TRUE if the existing value for @quark was replaced
+ * by @newval, %FALSE otherwise.
+ *
+ * Since: 2.34
+ */
+gboolean
+g_object_replace_qdata (GObject *object,
+ GQuark quark,
+ gpointer oldval,
+ gpointer newval,
+ GDestroyNotify destroy,
+ GDestroyNotify *old_destroy)
+{
+ g_return_val_if_fail (G_IS_OBJECT (object), FALSE);
+ g_return_val_if_fail (quark > 0, FALSE);
+
+ return g_datalist_id_replace_data (&object->qdata, quark,
+ oldval, newval, destroy,
+ old_destroy);
+}
+
+/**
* g_object_set_qdata_full: (skip)
* @object: The GObject to set store a user data pointer
* @quark: A #GQuark, naming the user data pointer
* set).
* Usually, calling this function is only required to update
* user data pointers with a destroy notifier, for example:
- * |[
+ * |[<!-- language="C" -->
* void
* object_add_to_user_list (GObject *object,
* const gchar *new_string)
}
/**
+ * g_object_dup_data:
+ * @object: the #GObject to store user data on
+ * @key: a string, naming the user data pointer
+ * @dup_func: (allow-none): function to dup the value
+ * @user_data: (allow-none): passed as user_data to @dup_func
+ *
+ * This is a variant of g_object_get_data() which returns
+ * a 'duplicate' of the value. @dup_func defines the
+ * meaning of 'duplicate' in this context, it could e.g.
+ * take a reference on a ref-counted object.
+ *
+ * If the @key is not set on the object then @dup_func
+ * will be called with a %NULL argument.
+ *
+ * Note that @dup_func is called while user data of @object
+ * is locked.
+ *
+ * This function can be useful to avoid races when multiple
+ * threads are using object data on the same key on the same
+ * object.
+ *
+ * Returns: the result of calling @dup_func on the value
+ * associated with @key on @object, or %NULL if not set.
+ * If @dup_func is %NULL, the value is returned
+ * unmodified.
+ *
+ * Since: 2.34
+ */
+gpointer
+g_object_dup_data (GObject *object,
+ const gchar *key,
+ GDuplicateFunc dup_func,
+ gpointer user_data)
+{
+ g_return_val_if_fail (G_IS_OBJECT (object), NULL);
+ g_return_val_if_fail (key != NULL, NULL);
+
+ return g_datalist_id_dup_data (&object->qdata,
+ g_quark_from_string (key),
+ dup_func, user_data);
+}
+
+/**
+ * g_object_replace_data:
+ * @object: the #GObject to store user data on
+ * @key: a string, naming the user data pointer
+ * @oldval: (allow-none): the old value to compare against
+ * @newval: (allow-none): the new value
+ * @destroy: (allow-none): a destroy notify for the new value
+ * @old_destroy: (allow-none): destroy notify for the existing value
+ *
+ * Compares the user data for the key @key on @object with
+ * @oldval, and if they are the same, replaces @oldval with
+ * @newval.
+ *
+ * This is like a typical atomic compare-and-exchange
+ * operation, for user data on an object.
+ *
+ * If the previous value was replaced then ownership of the
+ * old value (@oldval) is passed to the caller, including
+ * the registered destroy notify for it (passed out in @old_destroy).
+ * Its up to the caller to free this as he wishes, which may
+ * or may not include using @old_destroy as sometimes replacement
+ * should not destroy the object in the normal way.
+ *
+ * Returns: %TRUE if the existing value for @key was replaced
+ * by @newval, %FALSE otherwise.
+ *
+ * Since: 2.34
+ */
+gboolean
+g_object_replace_data (GObject *object,
+ const gchar *key,
+ gpointer oldval,
+ gpointer newval,
+ GDestroyNotify destroy,
+ GDestroyNotify *old_destroy)
+{
+ g_return_val_if_fail (G_IS_OBJECT (object), FALSE);
+ g_return_val_if_fail (key != NULL, FALSE);
+
+ return g_datalist_id_replace_data (&object->qdata,
+ g_quark_from_string (key),
+ oldval, newval, destroy,
+ old_destroy);
+}
+
+/**
* g_object_set_data_full: (skip)
* @object: #GObject containing the associations
* @key: name of the key
GObject *object = collect_values[0].v_pointer;
if (object->g_type_instance.g_class == NULL)
- return g_strconcat ("invalid unclassed object pointer for value type `",
+ return g_strconcat ("invalid unclassed object pointer for value type '",
G_VALUE_TYPE_NAME (value),
"'",
NULL);
else if (!g_value_type_compatible (G_OBJECT_TYPE (object), G_VALUE_TYPE (value)))
- return g_strconcat ("invalid object type `",
+ return g_strconcat ("invalid object type '",
G_OBJECT_TYPE_NAME (object),
- "' for value type `",
+ "' for value type '",
G_VALUE_TYPE_NAME (value),
"'",
NULL);
GObject **object_p = collect_values[0].v_pointer;
if (!object_p)
- return g_strdup_printf ("value location for `%s' passed as NULL", G_VALUE_TYPE_NAME (value));
+ return g_strdup_printf ("value location for '%s' passed as NULL", G_VALUE_TYPE_NAME (value));
if (!value->data[0].v_pointer)
*object_p = NULL;
* ensures that the @gobject stays alive during the call to @c_handler
* by temporarily adding a reference count to @gobject.
*
- * Note that there is a bug in GObject that makes this function
- * much less useful than it might seem otherwise. Once @gobject is
- * disposed, the callback will no longer be called, but, the signal
- * handler is <emphasis>not</emphasis> currently disconnected. If the
- * @instance is itself being freed at the same time than this doesn't
- * matter, since the signal will automatically be removed, but
- * if @instance persists, then the signal handler will leak. You
- * should not remove the signal yourself because in a future versions of
- * GObject, the handler <emphasis>will</emphasis> automatically
- * be disconnected.
- *
- * It's possible to work around this problem in a way that will
- * continue to work with future versions of GObject by checking
- * that the signal handler is still connected before disconnected it:
- * <informalexample><programlisting>
- * if (g_signal_handler_is_connected (instance, id))
- * g_signal_handler_disconnect (instance, id);
- * </programlisting></informalexample>
+ * When the @gobject is destroyed the signal handler will be automatically
+ * disconnected. Note that this is not currently threadsafe (ie:
+ * emitting a signal while @gobject is being destroyed in another thread
+ * is not safe).
*
* Returns: the handler id.
*/
/**
* g_closure_new_object:
* @sizeof_closure: the size of the structure to allocate, must be at least
- * <literal>sizeof (GClosure)</literal>
+ * `sizeof (GClosure)`
* @object: a #GObject pointer to store in the @data field of the newly
* allocated #GClosure
*
g_initially_unowned_class_init (GInitiallyUnownedClass *klass)
{
}
+
+/**
+ * GWeakRef:
+ *
+ * A structure containing a weak reference to a #GObject. It can either
+ * be empty (i.e. point to %NULL), or point to an object for as long as
+ * at least one "strong" reference to that object exists. Before the
+ * object's #GObjectClass.dispose method is called, every #GWeakRef
+ * associated with becomes empty (i.e. points to %NULL).
+ *
+ * Like #GValue, #GWeakRef can be statically allocated, stack- or
+ * heap-allocated, or embedded in larger structures.
+ *
+ * Unlike g_object_weak_ref() and g_object_add_weak_pointer(), this weak
+ * reference is thread-safe: converting a weak pointer to a reference is
+ * atomic with respect to invalidation of weak pointers to destroyed
+ * objects.
+ *
+ * If the object's #GObjectClass.dispose method results in additional
+ * references to the object being held, any #GWeakRefs taken
+ * before it was disposed will continue to point to %NULL. If
+ * #GWeakRefs are taken after the object is disposed and
+ * re-referenced, they will continue to point to it until its refcount
+ * goes back to zero, at which point they too will be invalidated.
+ */
+
+/**
+ * g_weak_ref_init: (skip)
+ * @weak_ref: (inout): uninitialized or empty location for a weak
+ * reference
+ * @object: (allow-none): a #GObject or %NULL
+ *
+ * Initialise a non-statically-allocated #GWeakRef.
+ *
+ * This function also calls g_weak_ref_set() with @object on the
+ * freshly-initialised weak reference.
+ *
+ * This function should always be matched with a call to
+ * g_weak_ref_clear(). It is not necessary to use this function for a
+ * #GWeakRef in static storage because it will already be
+ * properly initialised. Just use g_weak_ref_set() directly.
+ *
+ * Since: 2.32
+ */
+void
+g_weak_ref_init (GWeakRef *weak_ref,
+ gpointer object)
+{
+ weak_ref->priv.p = NULL;
+
+ g_weak_ref_set (weak_ref, object);
+}
+
+/**
+ * g_weak_ref_clear: (skip)
+ * @weak_ref: (inout): location of a weak reference, which
+ * may be empty
+ *
+ * Frees resources associated with a non-statically-allocated #GWeakRef.
+ * After this call, the #GWeakRef is left in an undefined state.
+ *
+ * You should only call this on a #GWeakRef that previously had
+ * g_weak_ref_init() called on it.
+ *
+ * Since: 2.32
+ */
+void
+g_weak_ref_clear (GWeakRef *weak_ref)
+{
+ g_weak_ref_set (weak_ref, NULL);
+
+ /* be unkind */
+ weak_ref->priv.p = (void *) 0xccccccccu;
+}
+
+/**
+ * g_weak_ref_get: (skip)
+ * @weak_ref: (inout): location of a weak reference to a #GObject
+ *
+ * If @weak_ref is not empty, atomically acquire a strong
+ * reference to the object it points to, and return that reference.
+ *
+ * This function is needed because of the potential race between taking
+ * the pointer value and g_object_ref() on it, if the object was losing
+ * its last reference at the same time in a different thread.
+ *
+ * The caller should release the resulting reference in the usual way,
+ * by using g_object_unref().
+ *
+ * Returns: (transfer full) (type GObject.Object): the object pointed to
+ * by @weak_ref, or %NULL if it was empty
+ *
+ * Since: 2.32
+ */
+gpointer
+g_weak_ref_get (GWeakRef *weak_ref)
+{
+ gpointer object_or_null;
+
+ g_return_val_if_fail (weak_ref!= NULL, NULL);
+
+ g_rw_lock_reader_lock (&weak_locations_lock);
+
+ object_or_null = weak_ref->priv.p;
+
+ if (object_or_null != NULL)
+ g_object_ref (object_or_null);
+
+ g_rw_lock_reader_unlock (&weak_locations_lock);
+
+ return object_or_null;
+}
+
+/**
+ * g_weak_ref_set: (skip)
+ * @weak_ref: location for a weak reference
+ * @object: (allow-none): a #GObject or %NULL
+ *
+ * Change the object to which @weak_ref points, or set it to
+ * %NULL.
+ *
+ * You must own a strong reference on @object while calling this
+ * function.
+ *
+ * Since: 2.32
+ */
+void
+g_weak_ref_set (GWeakRef *weak_ref,
+ gpointer object)
+{
+ GSList **weak_locations;
+ GObject *new_object;
+ GObject *old_object;
+
+ g_return_if_fail (weak_ref != NULL);
+ g_return_if_fail (object == NULL || G_IS_OBJECT (object));
+
+ new_object = object;
+
+ g_rw_lock_writer_lock (&weak_locations_lock);
+
+ /* We use the extra level of indirection here so that if we have ever
+ * had a weak pointer installed at any point in time on this object,
+ * we can see that there is a non-NULL value associated with the
+ * weak-pointer quark and know that this value will not change at any
+ * point in the object's lifetime.
+ *
+ * Both properties are important for reducing the amount of times we
+ * need to acquire locks and for decreasing the duration of time the
+ * lock is held while avoiding some rather tricky races.
+ *
+ * Specifically: we can avoid having to do an extra unconditional lock
+ * in g_object_unref() without worrying about some extremely tricky
+ * races.
+ */
+
+ old_object = weak_ref->priv.p;
+ if (new_object != old_object)
+ {
+ weak_ref->priv.p = new_object;
+
+ /* Remove the weak ref from the old object */
+ if (old_object != NULL)
+ {
+ weak_locations = g_datalist_id_get_data (&old_object->qdata, quark_weak_locations);
+ /* for it to point to an object, the object must have had it added once */
+ g_assert (weak_locations != NULL);
+
+ *weak_locations = g_slist_remove (*weak_locations, weak_ref);
+ }
+
+ /* Add the weak ref to the new object */
+ if (new_object != NULL)
+ {
+ weak_locations = g_datalist_id_get_data (&new_object->qdata, quark_weak_locations);
+
+ if (weak_locations == NULL)
+ {
+ weak_locations = g_new0 (GSList *, 1);
+ g_datalist_id_set_data_full (&new_object->qdata, quark_weak_locations, weak_locations, g_free);
+ }
+
+ *weak_locations = g_slist_prepend (*weak_locations, weak_ref);
+ }
+ }
+
+ g_rw_lock_writer_unlock (&weak_locations_lock);
+}
projects / platform / upstream / glib.git / blobdiff