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/* GObject - GLib Type, Object, Parameter and Signal Library
* Copyright (C) 1998-1999, 2000-2001 Tim Janik and Red Hat, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* 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, see <http://www.gnu.org/licenses/>.
*/
/*
* MT safe with regards to reference counting.
*/
#include "config.h"
#include <string.h>
#include <signal.h>
#include "gobject.h"
#include "gtype-private.h"
#include "gvaluecollector.h"
#include "gsignal.h"
#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()
*
* 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 [here][gobject-Signals].
*
* For a tutorial on implementing a new GObject class, see [How to define and
* implement a new GObject][howto-gobject]. For a list of naming conventions for
* GObjects and their methods, see the [GType conventions][gtype-conventions].
* For the high-level concepts behind GObject, read [Instantiable classed types:
* Objects][gtype-instantiable-classed].
*
* ## Floating references # {#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 "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 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.
*
* 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.
*
* 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:
*
* |[<!-- language="C" -->
* // save floating state
* gboolean was_floating = g_object_is_floating (object);
* g_object_ref_sink (object);
* // protected code portion
*
* ...
*
* // restore floating state
* if (was_floating)
* g_object_force_floating (object);
* else
* g_object_unref (object); // release previously acquired reference
* ]|
*/
/* --- macros --- */
#define PARAM_SPEC_PARAM_ID(pspec) ((pspec)->param_id)
#define PARAM_SPEC_SET_PARAM_ID(pspec, id) ((pspec)->param_id = (id))
#define OBJECT_HAS_TOGGLE_REF_FLAG 0x1
#define OBJECT_HAS_TOGGLE_REF(object) \
((g_datalist_get_flags (&(object)->qdata) & OBJECT_HAS_TOGGLE_REF_FLAG) != 0)
#define OBJECT_FLOATING_FLAG 0x2
#define CLASS_HAS_PROPS_FLAG 0x1
#define CLASS_HAS_PROPS(class) \
((class)->flags & CLASS_HAS_PROPS_FLAG)
#define CLASS_HAS_CUSTOM_CONSTRUCTOR(class) \
((class)->constructor != g_object_constructor)
#define CLASS_HAS_CUSTOM_CONSTRUCTED(class) \
((class)->constructed != g_object_constructed)
#define CLASS_HAS_DERIVED_CLASS_FLAG 0x2
#define CLASS_HAS_DERIVED_CLASS(class) \
((class)->flags & CLASS_HAS_DERIVED_CLASS_FLAG)
/* --- signals --- */
enum {
NOTIFY,
LAST_SIGNAL
};
/* --- properties --- */
enum {
PROP_NONE
};
/* --- prototypes --- */
static void g_object_base_class_init (GObjectClass *class);
static void g_object_base_class_finalize (GObjectClass *class);
static void g_object_do_class_init (GObjectClass *class);
static void g_object_init (GObject *object,
GObjectClass *class);
static GObject* g_object_constructor (GType type,
guint n_construct_properties,
GObjectConstructParam *construct_params);
static void g_object_constructed (GObject *object);
static void g_object_real_dispose (GObject *object);
static void g_object_finalize (GObject *object);
static void g_object_do_set_property (GObject *object,
guint property_id,
const GValue *value,
GParamSpec *pspec);
static void g_object_do_get_property (GObject *object,
guint property_id,
GValue *value,
GParamSpec *pspec);
static void g_value_object_init (GValue *value);
static void g_value_object_free_value (GValue *value);
static void g_value_object_copy_value (const GValue *src_value,
GValue *dest_value);
static void g_value_object_transform_value (const GValue *src_value,
GValue *dest_value);
static gpointer g_value_object_peek_pointer (const GValue *value);
static gchar* g_value_object_collect_value (GValue *value,
guint n_collect_values,
GTypeCValue *collect_values,
guint collect_flags);
static gchar* g_value_object_lcopy_value (const GValue *value,
guint n_collect_values,
GTypeCValue *collect_values,
guint collect_flags);
static void g_object_dispatch_properties_changed (GObject *object,
guint n_pspecs,
GParamSpec **pspecs);
static guint object_floating_flag_handler (GObject *object,
gint job);
static void object_interface_check_properties (gpointer check_data,
gpointer g_iface);
/* --- typedefs --- */
typedef struct _GObjectNotifyQueue GObjectNotifyQueue;
struct _GObjectNotifyQueue
{
GSList *pspecs;
guint16 n_pspecs;
guint16 freeze_count;
};
/* --- variables --- */
G_LOCK_DEFINE_STATIC (closure_array_mutex);
G_LOCK_DEFINE_STATIC (weak_refs_mutex);
G_LOCK_DEFINE_STATIC (toggle_refs_mutex);
static GQuark quark_closure_array = 0;
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;
/* 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);
/* --- functions --- */
static void
g_object_notify_queue_free (gpointer data)
{
GObjectNotifyQueue *nqueue = data;
g_slist_free (nqueue->pspecs);
g_slice_free (GObjectNotifyQueue, nqueue);
}
static GObjectNotifyQueue*
g_object_notify_queue_freeze (GObject *object,
gboolean conditional)
{
GObjectNotifyQueue *nqueue;
G_LOCK(notify_lock);
nqueue = g_datalist_id_get_data (&object->qdata, quark_notify_queue);
if (!nqueue)
{
if (conditional)
{
G_UNLOCK(notify_lock);
return NULL;
}
nqueue = g_slice_new0 (GObjectNotifyQueue);
g_datalist_id_set_data_full (&object->qdata, quark_notify_queue,
nqueue, g_object_notify_queue_free);
}
if (nqueue->freeze_count >= 65535)
g_critical("Free queue for %s (%p) is larger than 65535,"
" called g_object_freeze_notify() too often."
" Forgot to call g_object_thaw_notify() or infinite loop",
G_OBJECT_TYPE_NAME (object), object);
else
nqueue->freeze_count++;
G_UNLOCK(notify_lock);
return nqueue;
}
static void
g_object_notify_queue_thaw (GObject *object,
GObjectNotifyQueue *nqueue)
{
GParamSpec *pspecs_mem[16], **pspecs, **free_me = NULL;
GSList *slist;
guint n_pspecs = 0;
g_return_if_fail (nqueue->freeze_count > 0);
g_return_if_fail (g_atomic_int_get(&object->ref_count) > 0);
G_LOCK(notify_lock);
/* Just make sure we never get into some nasty race condition */
if (G_UNLIKELY(nqueue->freeze_count == 0)) {
G_UNLOCK(notify_lock);
g_warning ("%s: property-changed notification for %s(%p) is not frozen",
G_STRFUNC, G_OBJECT_TYPE_NAME (object), object);
return;
}
nqueue->freeze_count--;
if (nqueue->freeze_count) {
G_UNLOCK(notify_lock);
return;
}
pspecs = nqueue->n_pspecs > 16 ? free_me = g_new (GParamSpec*, nqueue->n_pspecs) : pspecs_mem;
for (slist = nqueue->pspecs; slist; slist = slist->next)
{
pspecs[n_pspecs++] = slist->data;
}
g_datalist_id_set_data (&object->qdata, quark_notify_queue, NULL);
G_UNLOCK(notify_lock);
if (n_pspecs)
G_OBJECT_GET_CLASS (object)->dispatch_properties_changed (object, n_pspecs, pspecs);
g_free (free_me);
}
static void
g_object_notify_queue_add (GObject *object,
GObjectNotifyQueue *nqueue,
GParamSpec *pspec)
{
G_LOCK(notify_lock);
g_assert (nqueue->n_pspecs < 65535);
if (g_slist_find (nqueue->pspecs, pspec) == NULL)
{
nqueue->pspecs = g_slist_prepend (nqueue->pspecs, pspec);
nqueue->n_pspecs++;
}
G_UNLOCK(notify_lock);
}
#ifdef G_ENABLE_DEBUG
G_LOCK_DEFINE_STATIC (debug_objects);
static guint debug_objects_count = 0;
static GHashTable *debug_objects_ht = NULL;
static void
debug_objects_foreach (gpointer key,
gpointer value,
gpointer user_data)
{
GObject *object = value;
g_message ("[%p] stale %s\tref_count=%u",
object,
G_OBJECT_TYPE_NAME (object),
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)
{
GOBJECT_IF_DEBUG (OBJECTS,
{
G_LOCK (debug_objects);
g_message ("stale GObjects: %u", debug_objects_count);
g_hash_table_foreach (debug_objects_ht, debug_objects_foreach, NULL);
G_UNLOCK (debug_objects);
});
}
#endif /* G_ENABLE_DEBUG */
void
_g_object_type_init (void)
{
static gboolean initialized = FALSE;
static const GTypeFundamentalInfo finfo = {
G_TYPE_FLAG_CLASSED | G_TYPE_FLAG_INSTANTIATABLE | G_TYPE_FLAG_DERIVABLE | G_TYPE_FLAG_DEEP_DERIVABLE,
};
GTypeInfo info = {
sizeof (GObjectClass),
(GBaseInitFunc) g_object_base_class_init,
(GBaseFinalizeFunc) g_object_base_class_finalize,
(GClassInitFunc) g_object_do_class_init,
NULL /* class_destroy */,
NULL /* class_data */,
sizeof (GObject),
0 /* n_preallocs */,
(GInstanceInitFunc) g_object_init,
NULL, /* value_table */
};
static const GTypeValueTable value_table = {
g_value_object_init, /* value_init */
g_value_object_free_value, /* value_free */
g_value_object_copy_value, /* value_copy */
g_value_object_peek_pointer, /* value_peek_pointer */
"p", /* collect_format */
g_value_object_collect_value, /* collect_value */
"p", /* lcopy_format */
g_value_object_lcopy_value, /* lcopy_value */
};
GType type;
g_return_if_fail (initialized == FALSE);
initialized = TRUE;
/* G_TYPE_OBJECT
*/
info.value_table = &value_table;
type = g_type_register_fundamental (G_TYPE_OBJECT, g_intern_static_string ("GObject"), &info, &finfo, 0);
g_assert (type == G_TYPE_OBJECT);
g_value_register_transform_func (G_TYPE_OBJECT, G_TYPE_OBJECT, g_value_object_transform_value);
#if G_ENABLE_DEBUG
/* We cannot use GOBJECT_IF_DEBUG here because of the G_HAS_CONSTRUCTORS
* conditional in between, as the C spec leaves conditionals inside macro
* expansions as undefined behavior. Only GCC and Clang are known to work
* but compilation breaks on MSVC.
*
* See: https://bugzilla.gnome.org/show_bug.cgi?id=769504
*/
if (_g_type_debug_flags & G_TYPE_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 */
}
static void
g_object_base_class_init (GObjectClass *class)
{
GObjectClass *pclass = g_type_class_peek_parent (class);
/* Don't inherit HAS_DERIVED_CLASS flag from parent class */
class->flags &= ~CLASS_HAS_DERIVED_CLASS_FLAG;
if (pclass)
pclass->flags |= CLASS_HAS_DERIVED_CLASS_FLAG;
/* reset instance specific fields and methods that don't get inherited */
class->construct_properties = pclass ? g_slist_copy (pclass->construct_properties) : NULL;
class->get_property = NULL;
class->set_property = NULL;
}
static void
g_object_base_class_finalize (GObjectClass *class)
{
GList *list, *node;
_g_signals_destroy (G_OBJECT_CLASS_TYPE (class));
g_slist_free (class->construct_properties);
class->construct_properties = NULL;
list = g_param_spec_pool_list_owned (pspec_pool, G_OBJECT_CLASS_TYPE (class));
for (node = list; node; node = node->next)
{
GParamSpec *pspec = node->data;
g_param_spec_pool_remove (pspec_pool, pspec);
PARAM_SPEC_SET_PARAM_ID (pspec, 0);
g_param_spec_unref (pspec);
}
g_list_free (list);
}
static void
g_object_do_class_init (GObjectClass *class)
{
/* read the comment about typedef struct CArray; on why not to change this quark */
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;
class->constructed = g_object_constructed;
class->set_property = g_object_do_set_property;
class->get_property = g_object_do_get_property;
class->dispose = g_object_real_dispose;
class->finalize = g_object_finalize;
class->dispatch_properties_changed = g_object_dispatch_properties_changed;
class->notify = NULL;
/**
* GObject::notify:
* @gobject: the object which received the signal.
* @pspec: the #GParamSpec of the property which changed.
*
* The notify signal is emitted on an object when one of its properties has
* its value set through g_object_set_property(), g_object_set(), et al.
*
* Note that getting this signal doesn’t itself guarantee that the value of
* the property has actually changed. When it is emitted is determined by the
* derived GObject class. If the implementor did not create the property with
* %G_PARAM_EXPLICIT_NOTIFY, then any call to g_object_set_property() results
* in ::notify being emitted, even if the new value is the same as the old.
* If they did pass %G_PARAM_EXPLICIT_NOTIFY, then this signal is emitted only
* when they explicitly call g_object_notify() or g_object_notify_by_pspec(),
* and common practice is to do that only when the value has actually changed.
*
* 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
* [canonical][canonical-parameter-name] parameter names as
* detail strings for the notify signal.
*/
gobject_signals[NOTIFY] =
g_signal_new (g_intern_static_string ("notify"),
G_TYPE_FROM_CLASS (class),
G_SIGNAL_RUN_FIRST | G_SIGNAL_NO_RECURSE | G_SIGNAL_DETAILED | G_SIGNAL_NO_HOOKS | G_SIGNAL_ACTION,
G_STRUCT_OFFSET (GObjectClass, notify),
NULL, NULL,
g_cclosure_marshal_VOID__PARAM,
G_TYPE_NONE,
1, G_TYPE_PARAM);
/* Install a check function that we'll use to verify that classes that
* implement an interface implement all properties for that interface
*/
g_type_add_interface_check (NULL, object_interface_check_properties);
}
static inline gboolean
install_property_internal (GType g_type,
guint property_id,
GParamSpec *pspec)
{
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_type_name (g_type),
pspec->name);
return FALSE;
}
g_param_spec_ref_sink (pspec);
PARAM_SPEC_SET_PARAM_ID (pspec, property_id);
g_param_spec_pool_insert (pspec_pool, pspec, g_type);
return TRUE;
}
static gboolean
validate_pspec_to_install (GParamSpec *pspec)
{
g_return_val_if_fail (G_IS_PARAM_SPEC (pspec), FALSE);
g_return_val_if_fail (PARAM_SPEC_PARAM_ID (pspec) == 0, FALSE); /* paranoid */
g_return_val_if_fail (pspec->flags & (G_PARAM_READABLE | G_PARAM_WRITABLE), FALSE);
if (pspec->flags & G_PARAM_CONSTRUCT)
g_return_val_if_fail ((pspec->flags & G_PARAM_CONSTRUCT_ONLY) == 0, FALSE);
if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))
g_return_val_if_fail (pspec->flags & G_PARAM_WRITABLE, FALSE);
return TRUE;
}
static gboolean
validate_and_install_class_property (GObjectClass *class,
GType oclass_type,
GType parent_type,
guint property_id,
GParamSpec *pspec)
{
if (!validate_pspec_to_install (pspec))
return FALSE;
if (pspec->flags & G_PARAM_WRITABLE)
g_return_val_if_fail (class->set_property != NULL, FALSE);
if (pspec->flags & G_PARAM_READABLE)
g_return_val_if_fail (class->get_property != NULL, FALSE);
class->flags |= CLASS_HAS_PROPS_FLAG;
if (install_property_internal (oclass_type, property_id, pspec))
{
if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))
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
*/
pspec = g_param_spec_pool_lookup (pspec_pool, pspec->name, parent_type, TRUE);
if (pspec && pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))
class->construct_properties = g_slist_remove (class->construct_properties, pspec);
return TRUE;
}
else
return FALSE;
}
/**
* g_object_class_install_property:
* @oclass: a #GObjectClass
* @property_id: the id for the new property
* @pspec: the #GParamSpec for the new property
*
* 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,
* e.g. to change the range of allowed values or the default value.
*/
void
g_object_class_install_property (GObjectClass *class,
guint property_id,
GParamSpec *pspec)
{
GType oclass_type, parent_type;
g_return_if_fail (G_IS_OBJECT_CLASS (class));
g_return_if_fail (property_id > 0);
oclass_type = G_OBJECT_CLASS_TYPE (class);
parent_type = g_type_parent (oclass_type);
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);
(void) validate_and_install_class_property (class,
oclass_type,
parent_type,
property_id,
pspec);
}
/**
* g_object_class_install_properties:
* @oclass: a #GObjectClass
* @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 #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.
*
* The property id of 0 is treated specially by #GObject and it should not
* be used to store a #GParamSpec.
*
* This function should be used if you plan to use a static array of
* #GParamSpecs and g_object_notify_by_pspec(). For instance, this
* class initialization:
*
* |[<!-- language="C" -->
* enum {
* PROP_0, PROP_FOO, PROP_BAR, N_PROPERTIES
* };
*
* static GParamSpec *obj_properties[N_PROPERTIES] = { NULL, };
*
* static void
* my_object_class_init (MyObjectClass *klass)
* {
* GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
*
* obj_properties[PROP_FOO] =
* g_param_spec_int ("foo", "Foo", "Foo",
* -1, G_MAXINT,
* 0,
* G_PARAM_READWRITE);
*
* obj_properties[PROP_BAR] =
* g_param_spec_string ("bar", "Bar", "Bar",
* NULL,
* G_PARAM_READWRITE);
*
* gobject_class->set_property = my_object_set_property;
* gobject_class->get_property = my_object_get_property;
* g_object_class_install_properties (gobject_class,
* N_PROPERTIES,
* obj_properties);
* }
* ]|
*
* allows calling g_object_notify_by_pspec() to notify of property changes:
*
* |[<!-- language="C" -->
* void
* my_object_set_foo (MyObject *self, gint foo)
* {
* if (self->foo != foo)
* {
* self->foo = foo;
* g_object_notify_by_pspec (G_OBJECT (self), obj_properties[PROP_FOO]);
* }
* }
* ]|
*
* Since: 2.26
*/
void
g_object_class_install_properties (GObjectClass *oclass,
guint n_pspecs,
GParamSpec **pspecs)
{
GType oclass_type, parent_type;
gint i;
g_return_if_fail (G_IS_OBJECT_CLASS (oclass));
g_return_if_fail (n_pspecs > 1);
g_return_if_fail (pspecs[0] == NULL);
if (CLASS_HAS_DERIVED_CLASS (oclass))
g_error ("Attempt to add properties to %s after it was derived",
G_OBJECT_CLASS_NAME (oclass));
oclass_type = G_OBJECT_CLASS_TYPE (oclass);
parent_type = g_type_parent (oclass_type);
/* we skip the first element of the array as it would have a 0 prop_id */
for (i = 1; i < n_pspecs; i++)
{
GParamSpec *pspec = pspecs[i];
if (!validate_and_install_class_property (oclass,
oclass_type,
parent_type,
i,
pspec))
{
break;
}
}
}
/**
* g_object_interface_install_property:
* @g_iface: (type GObject.TypeInterface): any interface vtable for the
* interface, or the default
* vtable for the interface.
* @pspec: the #GParamSpec for the new property
*
* Add a property to an interface; this is only useful for interfaces
* that are added to GObject-derived types. Adding a property to an
* interface forces all objects classes with that interface to have a
* compatible property. The compatible property could be a newly
* created #GParamSpec, but normally
* g_object_class_override_property() will be used so that the object
* class only needs to provide an implementation and inherits the
* property description, default value, bounds, and so forth from the
* interface property.
*
* This function is meant to be called from the interface's default
* vtable initialization function (the @class_init member of
* #GTypeInfo.) It must not be called after after @class_init has
* been called for any object types implementing this interface.
*
* If @pspec is a floating reference, it will be consumed.
*
* Since: 2.4
*/
void
g_object_interface_install_property (gpointer g_iface,
GParamSpec *pspec)
{
GTypeInterface *iface_class = g_iface;
g_return_if_fail (G_TYPE_IS_INTERFACE (iface_class->g_type));
g_return_if_fail (!G_IS_PARAM_SPEC_OVERRIDE (pspec)); /* paranoid */
if (!validate_pspec_to_install (pspec))
return;
(void) install_property_internal (iface_class->g_type, 0, pspec);
}
/**
* g_object_class_find_property:
* @oclass: a #GObjectClass
* @property_name: the name of the property to look up
*
* Looks up the #GParamSpec for a property of a class.
*
* Returns: (transfer none): the #GParamSpec for the property, or
* %NULL if the class doesn't have a property of that name
*/
GParamSpec*
g_object_class_find_property (GObjectClass *class,
const gchar *property_name)
{
GParamSpec *pspec;
GParamSpec *redirect;
g_return_val_if_fail (G_IS_OBJECT_CLASS (class), NULL);
g_return_val_if_fail (property_name != NULL, NULL);
pspec = g_param_spec_pool_lookup (pspec_pool,
property_name,
G_OBJECT_CLASS_TYPE (class),
TRUE);
if (pspec)
{
redirect = g_param_spec_get_redirect_target (pspec);
if (redirect)
return redirect;
else
return pspec;
}
else
return NULL;
}
/**
* g_object_interface_find_property:
* @g_iface: (type GObject.TypeInterface): any interface vtable for the
* interface, or the default vtable for the interface
* @property_name: name of a property to lookup.
*
* Find the #GParamSpec with the given name for an
* interface. Generally, the interface vtable passed in as @g_iface
* will be the default vtable from g_type_default_interface_ref(), or,
* if you know the interface has already been loaded,
* g_type_default_interface_peek().
*
* Since: 2.4
*
* Returns: (transfer none): the #GParamSpec for the property of the
* interface with the name @property_name, or %NULL if no
* such property exists.
*/
GParamSpec*
g_object_interface_find_property (gpointer g_iface,
const gchar *property_name)
{
GTypeInterface *iface_class = g_iface;
g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface_class->g_type), NULL);
g_return_val_if_fail (property_name != NULL, NULL);
return g_param_spec_pool_lookup (pspec_pool,
property_name,
iface_class->g_type,
FALSE);
}
/**
* g_object_class_override_property:
* @oclass: a #GObjectClass
* @property_id: the new property ID
* @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 "override" a property implementation in
* a parent class or to provide the implementation of a property from
* an interface.
*
* 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
* g_object_class_list_properties() will return the overridden
* property. However, in one case, the @construct_properties argument of
* the @constructor virtual function, the #GParamSpecOverride is passed
* instead, so that the @param_id field of the #GParamSpec will be
* 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().
*
* Since: 2.4
*/
void
g_object_class_override_property (GObjectClass *oclass,
guint property_id,
const gchar *name)
{
GParamSpec *overridden = NULL;
GParamSpec *new;
GType parent_type;
g_return_if_fail (G_IS_OBJECT_CLASS (oclass));
g_return_if_fail (property_id > 0);
g_return_if_fail (name != NULL);
/* Find the overridden property; first check parent types
*/
parent_type = g_type_parent (G_OBJECT_CLASS_TYPE (oclass));
if (parent_type != G_TYPE_NONE)
overridden = g_param_spec_pool_lookup (pspec_pool,
name,
parent_type,
TRUE);
if (!overridden)
{
GType *ifaces;
guint n_ifaces;
/* Now check interfaces
*/
ifaces = g_type_interfaces (G_OBJECT_CLASS_TYPE (oclass), &n_ifaces);
while (n_ifaces-- && !overridden)
{
overridden = g_param_spec_pool_lookup (pspec_pool,
name,
ifaces[n_ifaces],
FALSE);
}
g_free (ifaces);
}
if (!overridden)
{
g_warning ("%s: Can't find property to override for '%s::%s'",
G_STRFUNC, G_OBJECT_CLASS_NAME (oclass), name);
return;
}
new = g_param_spec_override (name, overridden);
g_object_class_install_property (oclass, property_id, new);
}
/**
* g_object_class_list_properties:
* @oclass: a #GObjectClass
* @n_properties: (out): return location for the length of the returned array
*
* Get an array of #GParamSpec* for all properties of a class.
*
* Returns: (array length=n_properties) (transfer container): an array of
* #GParamSpec* which should be freed after use
*/
GParamSpec** /* free result */
g_object_class_list_properties (GObjectClass *class,
guint *n_properties_p)
{
GParamSpec **pspecs;
guint n;
g_return_val_if_fail (G_IS_OBJECT_CLASS (class), NULL);
pspecs = g_param_spec_pool_list (pspec_pool,
G_OBJECT_CLASS_TYPE (class),
&n);
if (n_properties_p)
*n_properties_p = n;
return pspecs;
}
/**
* g_object_interface_list_properties:
* @g_iface: (type GObject.TypeInterface): any interface vtable for the
* interface, or the default vtable for the interface
* @n_properties_p: (out): location to store number of properties returned.
*
* Lists the properties of an interface.Generally, the interface
* vtable passed in as @g_iface will be the default vtable from
* g_type_default_interface_ref(), or, if you know the interface has
* already been loaded, g_type_default_interface_peek().
*
* Since: 2.4
*
* Returns: (array length=n_properties_p) (transfer container): a
* pointer to an array of pointers to #GParamSpec
* structures. The paramspecs are owned by GLib, but the
* array should be freed with g_free() when you are done with
* it.
*/
GParamSpec**
g_object_interface_list_properties (gpointer g_iface,
guint *n_properties_p)
{
GTypeInterface *iface_class = g_iface;
GParamSpec **pspecs;
guint n;
g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface_class->g_type), NULL);
pspecs = g_param_spec_pool_list (pspec_pool,
iface_class->g_type,
&n);
if (n_properties_p)
*n_properties_p = n;
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)
{
object->ref_count = 1;
object->qdata = NULL;
if (CLASS_HAS_PROPS (class))
{
/* freeze object's notification queue, g_object_newv() preserves pairedness */
g_object_notify_queue_freeze (object, FALSE);
}
if (CLASS_HAS_CUSTOM_CONSTRUCTOR (class))
{
/* 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);
}
GOBJECT_IF_DEBUG (OBJECTS,
{
G_LOCK (debug_objects);
debug_objects_count++;
g_hash_table_add (debug_objects_ht, object);
G_UNLOCK (debug_objects);
});
}
static void
g_object_do_set_property (GObject *object,
guint property_id,
const GValue *value,
GParamSpec *pspec)
{
switch (property_id)
{
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
break;
}
}
static void
g_object_do_get_property (GObject *object,
guint property_id,
GValue *value,
GParamSpec *pspec)
{
switch (property_id)
{
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
break;
}
}
static void
g_object_real_dispose (GObject *object)
{
g_signal_handlers_destroy (object);
g_datalist_id_set_data (&object->qdata, quark_closure_array, NULL);
g_datalist_id_set_data (&object->qdata, quark_weak_refs, NULL);
}
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);
GOBJECT_IF_DEBUG (OBJECTS,
{
G_LOCK (debug_objects);
g_assert (g_hash_table_contains (debug_objects_ht, object));
g_hash_table_remove (debug_objects_ht, object);
debug_objects_count--;
G_UNLOCK (debug_objects);
});
}
static void
g_object_dispatch_properties_changed (GObject *object,
guint n_pspecs,
GParamSpec **pspecs)
{
guint i;
for (i = 0; i < n_pspecs; i++)
g_signal_emit (object, gobject_signals[NOTIFY], g_param_spec_get_name_quark (pspecs[i]), pspecs[i]);
}
/**
* g_object_run_dispose:
* @object: a #GObject
*
* Releases all references to other objects. This can be used to break
* reference cycles.
*
* This function should only be called from object system implementations.
*/
void
g_object_run_dispose (GObject *object)
{
g_return_if_fail (G_IS_OBJECT (object));
g_return_if_fail (object->ref_count > 0);
g_object_ref (object);
TRACE (GOBJECT_OBJECT_DISPOSE(object,G_TYPE_FROM_INSTANCE(object), 0));
G_OBJECT_GET_CLASS (object)->dispose (object);
TRACE (GOBJECT_OBJECT_DISPOSE_END(object,G_TYPE_FROM_INSTANCE(object), 0));
g_object_unref (object);
}
/**
* g_object_freeze_notify:
* @object: a #GObject
*
* 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. 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.
*/
void
g_object_freeze_notify (GObject *object)
{
g_return_if_fail (G_IS_OBJECT (object));
if (g_atomic_int_get (&object->ref_count) == 0)
return;
g_object_ref (object);
g_object_notify_queue_freeze (object, FALSE);
g_object_unref (object);
}
static GParamSpec *
get_notify_pspec (GParamSpec *pspec)
{
GParamSpec *redirected;
/* we don't notify on non-READABLE parameters */
if (~pspec->flags & G_PARAM_READABLE)
return NULL;
/* if the paramspec is redirected, notify on the target */
redirected = g_param_spec_get_redirect_target (pspec);
if (redirected != NULL)
return redirected;
/* else, notify normally */
return pspec;
}
static inline void
g_object_notify_by_spec_internal (GObject *object,
GParamSpec *pspec)
{
GParamSpec *notify_pspec;
notify_pspec = get_notify_pspec (pspec);
if (notify_pspec != NULL)
{
GObjectNotifyQueue *nqueue;
/* conditional freeze: only increase freeze count if already frozen */
nqueue = g_object_notify_queue_freeze (object, TRUE);
if (nqueue != NULL)
{
/* we're frozen, so add to the queue and release our freeze */
g_object_notify_queue_add (object, nqueue, notify_pspec);
g_object_notify_queue_thaw (object, nqueue);
}
else
/* not frozen, so just dispatch the notification directly */
G_OBJECT_GET_CLASS (object)
->dispatch_properties_changed (object, 1, &notify_pspec);
}
}
/**
* g_object_notify:
* @object: a #GObject
* @property_name: the name of a property installed on the class of @object.
*
* Emits a "notify" signal for the property @property_name on @object.
*
* 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,
const gchar *property_name)
{
GParamSpec *pspec;
g_return_if_fail (G_IS_OBJECT (object));
g_return_if_fail (property_name != NULL);
if (g_atomic_int_get (&object->ref_count) == 0)
return;
g_object_ref (object);
/* We don't need to get the redirect target
* (by, e.g. calling g_object_class_find_property())
* because g_object_notify_queue_add() does that
*/
pspec = g_param_spec_pool_lookup (pspec_pool,
property_name,
G_OBJECT_TYPE (object),
TRUE);
if (!pspec)
g_warning ("%s: object class '%s' has no property named '%s'",
G_STRFUNC,
G_OBJECT_TYPE_NAME (object),
property_name);
else
g_object_notify_by_spec_internal (object, pspec);
g_object_unref (object);
}
/**
* g_object_notify_by_pspec:
* @object: a #GObject
* @pspec: the #GParamSpec of a property installed on the class of @object.
*
* Emits a "notify" signal for the property specified by @pspec on @object.
*
* This function omits the property name lookup, hence it is faster than
* g_object_notify().
*
* One way to avoid using g_object_notify() from within the
* class that registered the properties, and using g_object_notify_by_pspec()
* instead, is to store the GParamSpec used with
* g_object_class_install_property() inside a static array, e.g.:
*
*|[<!-- language="C" -->
* enum
* {
* PROP_0,
* PROP_FOO,
* PROP_LAST
* };
*
* static GParamSpec *properties[PROP_LAST];
*
* static void
* my_object_class_init (MyObjectClass *klass)
* {
* properties[PROP_FOO] = g_param_spec_int ("foo", "Foo", "The foo",
* 0, 100,
* 50,
* G_PARAM_READWRITE);
* g_object_class_install_property (gobject_class,
* PROP_FOO,
* properties[PROP_FOO]);
* }
* ]|
*
* and then notify a change on the "foo" property with:
*
* |[<!-- language="C" -->
* g_object_notify_by_pspec (self, properties[PROP_FOO]);
* ]|
*
* Since: 2.26
*/
void
g_object_notify_by_pspec (GObject *object,
GParamSpec *pspec)
{
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);
}
/**
* g_object_thaw_notify:
* @object: a #GObject
*
* Reverts the effect of a previous call to
* g_object_freeze_notify(). The freeze count is decreased on @object
* 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.
*/
void
g_object_thaw_notify (GObject *object)
{
GObjectNotifyQueue *nqueue;
g_return_if_fail (G_IS_OBJECT (object));
if (g_atomic_int_get (&object->ref_count) == 0)
return;
g_object_ref (object);
/* FIXME: Freezing is the only way to get at the notify queue.
* So we freeze once and then thaw twice.
*/
nqueue = g_object_notify_queue_freeze (object, FALSE);
g_object_notify_queue_thaw (object, nqueue);
g_object_notify_queue_thaw (object, nqueue);
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 = "0";
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,
GValue *value)
{
GObjectClass *class = g_type_class_peek (pspec->owner_type);
guint param_id = PARAM_SPEC_PARAM_ID (pspec);
GParamSpec *redirect;
if (class == NULL)
{
g_warning ("'%s::%s' is not a valid property name; '%s' is not a GObject subtype",
g_type_name (pspec->owner_type), pspec->name, g_type_name (pspec->owner_type));
return;
}
redirect = g_param_spec_get_redirect_target (pspec);
if (redirect)
pspec = redirect;
consider_issuing_property_deprecation_warning (pspec);
class->get_property (object, param_id, value, pspec);
}
static inline void
object_set_property (GObject *object,
GParamSpec *pspec,
const GValue *value,
GObjectNotifyQueue *nqueue)
{
GValue tmp_value = G_VALUE_INIT;
GObjectClass *class = g_type_class_peek (pspec->owner_type);
guint param_id = PARAM_SPEC_PARAM_ID (pspec);
GParamSpec *redirect;
if (class == NULL)
{
g_warning ("'%s::%s' is not a valid property name; '%s' is not a GObject subtype",
g_type_name (pspec->owner_type), pspec->name, g_type_name (pspec->owner_type));
return;
}
redirect = g_param_spec_get_redirect_target (pspec);
if (redirect)
pspec = redirect;
/* 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'",
pspec->name,
g_type_name (pspec->value_type),
G_VALUE_TYPE_NAME (value));
else if (g_param_value_validate (pspec, &tmp_value) && !(pspec->flags & G_PARAM_LAX_VALIDATION))
{
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'",
contents,
G_VALUE_TYPE_NAME (value),
pspec->name,
g_type_name (pspec->value_type));
g_free (contents);
}
else
{
class->set_property (object, param_id, &tmp_value, 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);
}
}
g_value_unset (&tmp_value);
}
static void
object_interface_check_properties (gpointer check_data,
gpointer g_iface)
{
GTypeInterface *iface_class = g_iface;
GObjectClass *class;
GType iface_type = iface_class->g_type;
GParamSpec **pspecs;
guint n;
class = g_type_class_ref (iface_class->g_instance_type);
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--)
{
GParamSpec *class_pspec = g_param_spec_pool_lookup (pspec_pool,
pspecs[n]->name,
G_OBJECT_CLASS_TYPE (class),
TRUE);
if (!class_pspec)
{
g_critical ("Object class %s doesn't implement property "
"'%s' from interface '%s'",
g_type_name (G_OBJECT_CLASS_TYPE (class)),
pspecs[n]->name,
g_type_name (iface_type));
continue;
}
/* 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.
*/
#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;
}
/* 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
* time only" is still more permissive than "read only".
*/
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);
}
GType
g_object_get_type (void)
{
return G_TYPE_OBJECT;
}
/**
* g_object_new: (skip)
* @object_type: the type id of the #GObject subtype to instantiate
* @first_property_name: the name of the first property
* @...: the value of the first property, followed optionally by more
* name/value pairs, followed by %NULL
*
* Creates a new instance of a #GObject subtype and sets its properties.
*
* Construction parameters (see #G_PARAM_CONSTRUCT, #G_PARAM_CONSTRUCT_ONLY)
* which are not explicitly specified are set to their default values.
*
* Returns: (transfer full) (type GObject.Object): a new instance of
* @object_type
*/
gpointer
g_object_new (GType object_type,
const gchar *first_property_name,
...)
{
GObject *object;
va_list var_args;
/* short circuit for calls supplying no properties */
if (!first_property_name)
return g_object_new_with_properties (object_type, 0, NULL, NULL);
va_start (var_args, first_property_name);
object = g_object_new_valist (object_type, first_property_name, var_args);
va_end (var_args);
return object;
}
static gpointer
g_object_new_with_custom_constructor (GObjectClass *class,
GObjectConstructParam *params,
guint n_params)
{
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)
{
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)
{
value = &cvalues[cvals_used++];
g_value_init (value, pspec->value_type);
g_param_value_set_default (pspec, value);
}
cparams[i].pspec = pspec;
cparams[i].value = value;
i++;
}
/* 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 gpointer
g_object_new_internal (GObjectClass *class,
GObjectConstructParam *params,
guint n_params)
{
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;
}
static inline gboolean
g_object_new_is_valid_property (GType object_type,
GParamSpec *pspec,
const char *name,
GObjectConstructParam *params,
int n_params)
{
gint i;
if (G_UNLIKELY (pspec == NULL))
{
g_critical ("%s: object class '%s' has no property named '%s'",
G_STRFUNC, g_type_name (object_type), name);
return FALSE;
}
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));
return FALSE;
}
if (G_UNLIKELY (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));
return FALSE;
}
}
return TRUE;
}
/**
* g_object_new_with_properties: (skip)
* @object_type: the object type to instantiate
* @n_properties: the number of properties
* @names: (array length=n_properties): the names of each property to be set
* @values: (array length=n_properties): the values of each property to be set
*
* Creates a new instance of a #GObject subtype and sets its properties using
* the provided arrays. Both arrays must have exactly @n_properties elements,
* and the names and values correspond by index.
*
* Construction parameters (see %G_PARAM_CONSTRUCT, %G_PARAM_CONSTRUCT_ONLY)
* which are not explicitly specified are set to their default values.
*
* Returns: (type GObject.Object) (transfer full): a new instance of
* @object_type
*
* Since: 2.54
*/
GObject *
g_object_new_with_properties (GType object_type,
guint n_properties,
const char *names[],
const GValue values[])
{
GObjectClass *class, *unref_class = NULL;
GObject *object;
g_return_val_if_fail (G_TYPE_IS_OBJECT (object_type), 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 == NULL)
class = unref_class = g_type_class_ref (object_type);
if (n_properties > 0)
{
guint i, count = 0;
GObjectConstructParam *params;
params = g_newa (GObjectConstructParam, n_properties);
for (i = 0; i < n_properties; i++)
{
GParamSpec *pspec;
pspec = g_param_spec_pool_lookup (pspec_pool, names[i], object_type, TRUE);
if (!g_object_new_is_valid_property (object_type, pspec, names[i], params, count))
continue;
params[count].pspec = pspec;
/* Init GValue */
params[count].value = g_newa (GValue, 1);
memset (params[count].value, 0, sizeof (GValue));
g_value_init (params[count].value, G_VALUE_TYPE (&values[i]));
g_value_copy (&values[i], params[count].value);
count++;
}
object = g_object_new_internal (class, params, count);
while (count--)
g_value_unset (params[count].value);
}
else
object = g_object_new_internal (class, NULL, 0);
if (unref_class != NULL)
g_type_class_unref (unref_class);
return object;
}
/**
* g_object_newv:
* @object_type: the type id of the #GObject subtype to instantiate
* @n_parameters: the length of the @parameters array
* @parameters: (array length=n_parameters): an array of #GParameter
*
* Creates a new instance of a #GObject subtype and sets its properties.
*
* Construction parameters (see #G_PARAM_CONSTRUCT, #G_PARAM_CONSTRUCT_ONLY)
* which are not explicitly specified are set to their default values.
*
* Returns: (type GObject.Object) (transfer full): a new instance of
* @object_type
*
* Deprecated: 2.54: Use g_object_new_with_properties() instead.
* deprecated. See #GParameter for more information.
*/
gpointer
g_object_newv (GType object_type,
guint n_parameters,
GParameter *parameters)
{
GObjectClass *class, *unref_class = NULL;
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);
if (n_parameters)
{
GObjectConstructParam *cparams;
guint i, j;
cparams = g_newa (GObjectConstructParam, n_parameters);
j = 0;
for (i = 0; i < n_parameters; i++)
{
GParamSpec *pspec;
pspec = g_param_spec_pool_lookup (pspec_pool, parameters[i].name, object_type, TRUE);
if (!g_object_new_is_valid_property (object_type, pspec, parameters[i].name, cparams, j))
continue;
cparams[j].pspec = pspec;
cparams[j].value = &parameters[i].value;
j++;
}
object = g_object_new_internal (class, cparams, j);
}
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;
}
/**
* g_object_new_valist: (skip)
* @object_type: the type id of the #GObject subtype to instantiate
* @first_property_name: the name of the first property
* @var_args: the value of the first property, followed optionally by more
* name/value pairs, followed by %NULL
*
* Creates a new instance of a #GObject subtype and sets its properties.
*
* Construction parameters (see #G_PARAM_CONSTRUCT, #G_PARAM_CONSTRUCT_ONLY)
* which are not explicitly specified are set to their default values.
*
* Returns: a new instance of @object_type
*/
GObject*
g_object_new_valist (GType object_type,
const gchar *first_property_name,
va_list var_args)
{
GObjectClass *class, *unref_class = NULL;
GObject *object;
g_return_val_if_fail (G_TYPE_IS_OBJECT (object_type), 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);
if (first_property_name)
{
GObjectConstructParam stack_params[16];
GObjectConstructParam *params;
const gchar *name;
gint n_params = 0;
name = first_property_name;
params = stack_params;
do
{
gchar *error = NULL;
GParamSpec *pspec;
pspec = g_param_spec_pool_lookup (pspec_pool, name, object_type, TRUE);
if (!g_object_new_is_valid_property (object_type, pspec, name, params, n_params))
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 *)));
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;
}
static GObject*
g_object_constructor (GType type,
guint n_construct_properties,
GObjectConstructParam *construct_params)
{
GObject *object;
/* create object */
object = (GObject*) g_type_create_instance (type);
/* set construction parameters */
if (n_construct_properties)
{
GObjectNotifyQueue *nqueue = g_object_notify_queue_freeze (object, FALSE);
/* set construct properties */
while (n_construct_properties--)
{
GValue *value = construct_params->value;
GParamSpec *pspec = construct_params->pspec;
construct_params++;
object_set_property (object, pspec, value, nqueue);
}
g_object_notify_queue_thaw (object, nqueue);
/* the notification queue is still frozen from g_object_init(), so
* we don't need to handle it here, g_object_newv() takes
* care of that
*/
}
return object;
}
static void
g_object_constructed (GObject *object)
{
/* empty default impl to allow unconditional upchaining */
}
static inline gboolean
g_object_set_is_valid_property (GObject *object,
GParamSpec *pspec,
const char *property_name)
{
if (G_UNLIKELY (pspec == NULL))
{
g_warning ("%s: object class '%s' has no property named '%s'",
G_STRFUNC, G_OBJECT_TYPE_NAME (object), property_name);
return FALSE;
}
if (G_UNLIKELY (!(pspec->flags & G_PARAM_WRITABLE)))
{
g_warning ("%s: property '%s' of object class '%s' is not writable",
G_STRFUNC, pspec->name, G_OBJECT_TYPE_NAME (object));
return FALSE;
}
if (G_UNLIKELY (((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));
return FALSE;
}
return TRUE;
}
/**
* g_object_setv: (skip)
* @object: a #GObject
* @n_properties: the number of properties
* @names: (array length=n_properties): the names of each property to be set
* @values: (array length=n_properties): the values of each property to be set
*
* Sets @n_properties properties for an @object.
* Properties to be set will be taken from @values. All properties must be
* valid. Warnings will be emitted and undefined behaviour may result if invalid
* properties are passed in.
*
* Since: 2.54
*/
void
g_object_setv (GObject *object,
guint n_properties,
const gchar *names[],
const GValue values[])
{
guint i;
GObjectNotifyQueue *nqueue;
GParamSpec *pspec;
GType obj_type;
g_return_if_fail (G_IS_OBJECT (object));
if (n_properties == 0)
return;
g_object_ref (object);
obj_type = G_OBJECT_TYPE (object);
nqueue = g_object_notify_queue_freeze (object, FALSE);
for (i = 0; i < n_properties; i++)
{
pspec = g_param_spec_pool_lookup (pspec_pool, names[i], obj_type, TRUE);
if (!g_object_set_is_valid_property (object, pspec, names[i]))
break;
consider_issuing_property_deprecation_warning (pspec);
object_set_property (object, pspec, &values[i], nqueue);
}
g_object_notify_queue_thaw (object, nqueue);
g_object_unref (object);
}
/**
* g_object_set_valist: (skip)
* @object: a #GObject
* @first_property_name: name of the first property to set
* @var_args: value for the first property, followed optionally by more
* name/value pairs, followed by %NULL
*
* Sets properties on an object.
*/
void
g_object_set_valist (GObject *object,
const gchar *first_property_name,
va_list var_args)
{
GObjectNotifyQueue *nqueue;
const gchar *name;
g_return_if_fail (G_IS_OBJECT (object));
g_object_ref (object);
nqueue = g_object_notify_queue_freeze (object, FALSE);
name = first_property_name;
while (name)
{
GValue value = G_VALUE_INIT;
GParamSpec *pspec;
gchar *error = NULL;
pspec = g_param_spec_pool_lookup (pspec_pool,
name,
G_OBJECT_TYPE (object),
TRUE);
if (!g_object_set_is_valid_property (object, pspec, name))
break;
G_VALUE_COLLECT_INIT (&value, pspec->value_type, var_args,
0, &error);
if (error)
{
g_warning ("%s: %s", G_STRFUNC, error);
g_free (error);
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*);
}
g_object_notify_queue_thaw (object, nqueue);
g_object_unref (object);
}
static inline gboolean
g_object_get_is_valid_property (GObject *object,
GParamSpec *pspec,
const char *property_name)
{
if (G_UNLIKELY (pspec == NULL))
{
g_warning ("%s: object class '%s' has no property named '%s'",
G_STRFUNC, G_OBJECT_TYPE_NAME (object), property_name);
return FALSE;
}
if (G_UNLIKELY (!(pspec->flags & G_PARAM_READABLE)))
{
g_warning ("%s: property '%s' of object class '%s' is not readable",
G_STRFUNC, pspec->name, G_OBJECT_TYPE_NAME (object));
return FALSE;
}
return TRUE;
}
/**
* g_object_getv:
* @object: a #GObject
* @n_properties: the number of properties
* @names: (array length=n_properties): the names of each property to get
* @values: (array length=n_properties): the values of each property to get
*
* Gets @n_properties properties for an @object.
* Obtained properties will be set to @values. All properties must be valid.
* Warnings will be emitted and undefined behaviour may result if invalid
* properties are passed in.
*
* Since: 2.54
*/
void
g_object_getv (GObject *object,
guint n_properties,
const gchar *names[],
GValue values[])
{
guint i;
GParamSpec *pspec;
GType obj_type;
g_return_if_fail (G_IS_OBJECT (object));
if (n_properties == 0)
return;
g_object_ref (object);
obj_type = G_OBJECT_TYPE (object);
for (i = 0; i < n_properties; i++)
{
pspec = g_param_spec_pool_lookup (pspec_pool,
names[i],
obj_type,
TRUE);
if (!g_object_get_is_valid_property (object, pspec, names[i]))
break;
memset (&values[i], 0, sizeof (GValue));
g_value_init (&values[i], pspec->value_type);
object_get_property (object, pspec, &values[i]);
}
g_object_unref (object);
}
/**
* g_object_get_valist: (skip)
* @object: a #GObject
* @first_property_name: name of the first property to get
* @var_args: return location for the first property, followed optionally by more
* name/return location pairs, followed by %NULL
*
* Gets properties of an object.
*
* In general, a copy is made of the property contents and the caller
* is responsible for freeing the memory in the appropriate manner for
* the type, for instance by calling g_free() or g_object_unref().
*
* See g_object_get().
*/
void
g_object_get_valist (GObject *object,
const gchar *first_property_name,
va_list var_args)
{
const gchar *name;
g_return_if_fail (G_IS_OBJECT (object));
g_object_ref (object);
name = first_property_name;
while (name)
{
GValue value = G_VALUE_INIT;
GParamSpec *pspec;
gchar *error;
pspec = g_param_spec_pool_lookup (pspec_pool,
name,
G_OBJECT_TYPE (object),
TRUE);
if (!g_object_get_is_valid_property (object, pspec, name))
break;
g_value_init (&value, pspec->value_type);
object_get_property (object, pspec, &value);
G_VALUE_LCOPY (&value, var_args, 0, &error);
if (error)
{
g_warning ("%s: %s", G_STRFUNC, error);
g_free (error);
g_value_unset (&value);
break;
}
g_value_unset (&value);
name = va_arg (var_args, gchar*);
}
g_object_unref (object);
}
/**
* g_object_set: (skip)
* @object: (type GObject.Object): a #GObject
* @first_property_name: name of the first property to set
* @...: value for the first property, followed optionally by more
* 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,
const gchar *first_property_name,
...)
{
GObject *object = _object;
va_list var_args;
g_return_if_fail (G_IS_OBJECT (object));
va_start (var_args, first_property_name);
g_object_set_valist (object, first_property_name, var_args);
va_end (var_args);
}
/**
* g_object_get: (skip)
* @object: (type GObject.Object): a #GObject
* @first_property_name: name of the first property to get
* @...: return location for the first property, followed optionally by more
* name/return location pairs, followed by %NULL
*
* Gets properties of an object.
*
* In general, a copy is made of the property contents and the caller
* is responsible for freeing the memory in the appropriate manner for
* the type, for instance by calling g_free() or g_object_unref().
*
* 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_object_get (my_object,
* "int-property", &intval,
* "str-property", &strval,
* "obj-property", &objval,
* NULL);
*
* // Do something with intval, strval, objval
*
* g_free (strval);
* g_object_unref (objval);
* ]|
*/
void
g_object_get (gpointer _object,
const gchar *first_property_name,
...)
{
GObject *object = _object;
va_list var_args;
g_return_if_fail (G_IS_OBJECT (object));
va_start (var_args, first_property_name);
g_object_get_valist (object, first_property_name, var_args);
va_end (var_args);
}
/**
* g_object_set_property:
* @object: a #GObject
* @property_name: the name of the property to set
* @value: the value
*
* Sets a property on an object.
*/
void
g_object_set_property (GObject *object,
const gchar *property_name,
const GValue *value)
{
g_object_setv (object, 1, &property_name, value);
}
/**
* g_object_get_property:
* @object: a #GObject
* @property_name: the name of the property to get
* @value: return location for the property value
*
* Gets a property of an object. @value must have been initialized to the
* expected type of the property (or a type to which the expected type can be
* transformed) using g_value_init().
*
* In general, a copy is made of the property contents and the caller is
* responsible for freeing the memory by calling g_value_unset().
*
* Note that g_object_get_property() is really intended for language
* bindings, g_object_get() is much more convenient for C programming.
*/
void
g_object_get_property (GObject *object,
const gchar *property_name,
GValue *value)
{
GParamSpec *pspec;
g_return_if_fail (G_IS_OBJECT (object));
g_return_if_fail (property_name != NULL);
g_return_if_fail (G_IS_VALUE (value));
g_object_ref (object);
pspec = g_param_spec_pool_lookup (pspec_pool,
property_name,
G_OBJECT_TYPE (object),
TRUE);
if (g_object_get_is_valid_property (object, pspec, property_name))
{
GValue *prop_value, tmp_value = G_VALUE_INIT;
/* auto-conversion of the callers value type
*/
if (G_VALUE_TYPE (value) == pspec->value_type)
{
g_value_reset (value);
prop_value = value;
}
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_STRFUNC, pspec->name,
g_type_name (pspec->value_type),
G_VALUE_TYPE_NAME (value));
g_object_unref (object);
return;
}
else
{
g_value_init (&tmp_value, pspec->value_type);
prop_value = &tmp_value;
}
object_get_property (object, pspec, prop_value);
if (prop_value != value)
{
g_value_transform (prop_value, value);
g_value_unset (&tmp_value);
}
}
g_object_unref (object);
}
/**
* g_object_connect: (skip)
* @object: (type GObject.Object): a #GObject
* @signal_spec: the spec for the first signal
* @...: #GCallback for the first signal, followed by data for the
* first signal, followed optionally by more signal
* spec/callback/data triples, followed by %NULL
*
* A convenience function to connect multiple signals at once.
*
* The signal specs expected by this function have the form
* "modifier::signal_name", where modifier can be one of the following:
* * - 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,
* NULL);
* ]|
*
* Returns: (transfer none) (type GObject.Object): @object
*/
gpointer
g_object_connect (gpointer _object,
const gchar *signal_spec,
...)
{
GObject *object = _object;
va_list var_args;
g_return_val_if_fail (G_IS_OBJECT (object), NULL);
g_return_val_if_fail (object->ref_count > 0, object);
va_start (var_args, signal_spec);
while (signal_spec)
{
GCallback callback = va_arg (var_args, GCallback);
gpointer data = va_arg (var_args, gpointer);
if (strncmp (signal_spec, "signal::", 8) == 0)
g_signal_connect_data (object, signal_spec + 8,
callback, data, NULL,
0);
else if (strncmp (signal_spec, "object_signal::", 15) == 0 ||
strncmp (signal_spec, "object-signal::", 15) == 0)
g_signal_connect_object (object, signal_spec + 15,
callback, data,
0);
else if (strncmp (signal_spec, "swapped_signal::", 16) == 0 ||
strncmp (signal_spec, "swapped-signal::", 16) == 0)
g_signal_connect_data (object, signal_spec + 16,
callback, data, NULL,
G_CONNECT_SWAPPED);
else if (strncmp (signal_spec, "swapped_object_signal::", 23) == 0 ||
strncmp (signal_spec, "swapped-object-signal::", 23) == 0)
g_signal_connect_object (object, signal_spec + 23,
callback, data,
G_CONNECT_SWAPPED);
else if (strncmp (signal_spec, "signal_after::", 14) == 0 ||
strncmp (signal_spec, "signal-after::", 14) == 0)
g_signal_connect_data (object, signal_spec + 14,
callback, data, NULL,
G_CONNECT_AFTER);
else if (strncmp (signal_spec, "object_signal_after::", 21) == 0 ||
strncmp (signal_spec, "object-signal-after::", 21) == 0)
g_signal_connect_object (object, signal_spec + 21,
callback, data,
G_CONNECT_AFTER);
else if (strncmp (signal_spec, "swapped_signal_after::", 22) == 0 ||
strncmp (signal_spec, "swapped-signal-after::", 22) == 0)
g_signal_connect_data (object, signal_spec + 22,
callback, data, NULL,
G_CONNECT_SWAPPED | G_CONNECT_AFTER);
else if (strncmp (signal_spec, "swapped_object_signal_after::", 29) == 0 ||
strncmp (signal_spec, "swapped-object-signal-after::", 29) == 0)
g_signal_connect_object (object, signal_spec + 29,
callback, data,
G_CONNECT_SWAPPED | G_CONNECT_AFTER);
else
{
g_warning ("%s: invalid signal spec \"%s\"", G_STRFUNC, signal_spec);
break;
}
signal_spec = va_arg (var_args, gchar*);
}
va_end (var_args);
return object;
}
/**
* g_object_disconnect: (skip)
* @object: (type GObject.Object): a #GObject
* @signal_spec: the spec for the first signal
* @...: #GCallback for the first signal, followed by data for the first signal,
* followed optionally by more signal spec/callback/data triples,
* followed by %NULL
*
* A convenience function to disconnect multiple signals at once.
*
* The signal specs expected by this function have the form
* "any_signal", which means to disconnect any signal with matching
* callback and data, or "any_signal::signal_name", which only
* disconnects the signal named "signal_name".
*/
void
g_object_disconnect (gpointer _object,
const gchar *signal_spec,
...)
{
GObject *object = _object;
va_list var_args;
g_return_if_fail (G_IS_OBJECT (object));
g_return_if_fail (object->ref_count > 0);
va_start (var_args, signal_spec);
while (signal_spec)
{
GCallback callback = va_arg (var_args, GCallback);
gpointer data = va_arg (var_args, gpointer);
guint sid = 0, detail = 0, mask = 0;
if (strncmp (signal_spec, "any_signal::", 12) == 0 ||
strncmp (signal_spec, "any-signal::", 12) == 0)
{
signal_spec += 12;
mask = G_SIGNAL_MATCH_ID | G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA;
}
else if (strcmp (signal_spec, "any_signal") == 0 ||
strcmp (signal_spec, "any-signal") == 0)
{
signal_spec += 10;
mask = G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA;
}
else
{
g_warning ("%s: invalid signal spec \"%s\"", G_STRFUNC, signal_spec);
break;
}
if ((mask & G_SIGNAL_MATCH_ID) &&
!g_signal_parse_name (signal_spec, G_OBJECT_TYPE (object), &sid, &detail, FALSE))
g_warning ("%s: invalid signal name \"%s\"", G_STRFUNC, signal_spec);
else if (!g_signal_handlers_disconnect_matched (object, mask | (detail ? G_SIGNAL_MATCH_DETAIL : 0),
sid, detail,
NULL, (gpointer)callback, data))
g_warning ("%s: signal handler %p(%p) is not connected", G_STRFUNC, callback, data);
signal_spec = va_arg (var_args, gchar*);
}
va_end (var_args);
}
typedef struct {
GObject *object;
guint n_weak_refs;
struct {
GWeakNotify notify;
gpointer data;
} weak_refs[1]; /* flexible array */
} WeakRefStack;
static void
weak_refs_notify (gpointer data)
{
WeakRefStack *wstack = data;
guint i;
for (i = 0; i < wstack->n_weak_refs; i++)
wstack->weak_refs[i].notify (wstack->weak_refs[i].data, wstack->object);
g_free (wstack);
}
/**
* g_object_weak_ref: (skip)
* @object: #GObject to reference weakly
* @notify: callback to invoke before the object is freed
* @data: extra data to pass to notify
*
* Adds a weak reference callback to an object. Weak references are
* used for notification when an object is finalized. They are called
* "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,
GWeakNotify notify,
gpointer data)
{
WeakRefStack *wstack;
guint i;
g_return_if_fail (G_IS_OBJECT (object));
g_return_if_fail (notify != NULL);
g_return_if_fail (object->ref_count >= 1);
G_LOCK (weak_refs_mutex);
wstack = g_datalist_id_remove_no_notify (&object->qdata, quark_weak_refs);
if (wstack)
{
i = wstack->n_weak_refs++;
wstack = g_realloc (wstack, sizeof (*wstack) + sizeof (wstack->weak_refs[0]) * i);
}
else
{
wstack = g_renew (WeakRefStack, NULL, 1);
wstack->object = object;
wstack->n_weak_refs = 1;
i = 0;
}
wstack->weak_refs[i].notify = notify;
wstack->weak_refs[i].data = data;
g_datalist_id_set_data_full (&object->qdata, quark_weak_refs, wstack, weak_refs_notify);
G_UNLOCK (weak_refs_mutex);
}
/**
* g_object_weak_unref: (skip)
* @object: #GObject to remove a weak reference from
* @notify: callback to search for
* @data: data to search for
*
* Removes a weak reference callback to an object.
*/
void
g_object_weak_unref (GObject *object,
GWeakNotify notify,
gpointer data)
{
WeakRefStack *wstack;
gboolean found_one = FALSE;
g_return_if_fail (G_IS_OBJECT (object));
g_return_if_fail (notify != NULL);
G_LOCK (weak_refs_mutex);
wstack = g_datalist_id_get_data (&object->qdata, quark_weak_refs);
if (wstack)
{
guint i;
for (i = 0; i < wstack->n_weak_refs; i++)
if (wstack->weak_refs[i].notify == notify &&
wstack->weak_refs[i].data == data)
{
found_one = TRUE;
wstack->n_weak_refs -= 1;
if (i != wstack->n_weak_refs)
wstack->weak_refs[i] = wstack->weak_refs[wstack->n_weak_refs];
break;
}
}
G_UNLOCK (weak_refs_mutex);
if (!found_one)
g_warning ("%s: couldn't find weak ref %p(%p)", G_STRFUNC, notify, data);
}
/**
* g_object_add_weak_pointer: (skip)
* @object: The object that should be weak referenced.
* @weak_pointer_location: (inout) (not optional): The memory address
* of a pointer.
*
* Adds a weak reference from weak_pointer to @object to indicate that
* 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,
gpointer *weak_pointer_location)
{
g_return_if_fail (G_IS_OBJECT (object));
g_return_if_fail (weak_pointer_location != NULL);
g_object_weak_ref (object,
(GWeakNotify) g_nullify_pointer,
weak_pointer_location);
}
/**
* g_object_remove_weak_pointer: (skip)
* @object: The object that is weak referenced.
* @weak_pointer_location: (inout) (not optional): The memory address
* of a pointer.
*
* Removes a weak reference from @object that was previously added
* using g_object_add_weak_pointer(). The @weak_pointer_location has
* to match the one used with g_object_add_weak_pointer().
*/
void
g_object_remove_weak_pointer (GObject *object,
gpointer *weak_pointer_location)
{
g_return_if_fail (G_IS_OBJECT (object));
g_return_if_fail (weak_pointer_location != NULL);
g_object_weak_unref (object,
(GWeakNotify) g_nullify_pointer,
weak_pointer_location);
}
static guint
object_floating_flag_handler (GObject *object,
gint job)
{
switch (job)
{
gpointer oldvalue;
case +1: /* force floating if possible */
do
oldvalue = g_atomic_pointer_get (&object->qdata);
while (!g_atomic_pointer_compare_and_exchange ((void**) &object->qdata, oldvalue,
(gpointer) ((gsize) oldvalue | OBJECT_FLOATING_FLAG)));
return (gsize) oldvalue & OBJECT_FLOATING_FLAG;
case -1: /* sink if possible */
do
oldvalue = g_atomic_pointer_get (&object->qdata);
while (!g_atomic_pointer_compare_and_exchange ((void**) &object->qdata, oldvalue,
(gpointer) ((gsize) oldvalue & ~(gsize) OBJECT_FLOATING_FLAG)));
return (gsize) oldvalue & OBJECT_FLOATING_FLAG;
default: /* check floating */
return 0 != ((gsize) g_atomic_pointer_get (&object->qdata) & OBJECT_FLOATING_FLAG);
}
}
/**
* g_object_is_floating:
* @object: (type GObject.Object): a #GObject
*
* Checks whether @object has a [floating][floating-ref] reference.
*
* Since: 2.10
*
* Returns: %TRUE if @object has a floating reference
*/
gboolean
g_object_is_floating (gpointer _object)
{
GObject *object = _object;
g_return_val_if_fail (G_IS_OBJECT (object), FALSE);
return floating_flag_handler (object, 0);
}
/**
* g_object_ref_sink:
* @object: (type GObject.Object): a #GObject
*
* Increase the reference count of @object, and possibly remove the
* [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
* reference by clearing the floating flag while leaving the reference
* count unchanged. If the object is not floating, then this call
* adds a new normal reference increasing the reference count by one.
*
* Since GLib 2.56, the type of @object will be propagated to the return type
* under the same conditions as for g_object_ref().
*
* Since: 2.10
*
* Returns: (type GObject.Object) (transfer none): @object
*/
gpointer
(g_object_ref_sink) (gpointer _object)
{
GObject *object = _object;
gboolean was_floating;
g_return_val_if_fail (G_IS_OBJECT (object), object);
g_return_val_if_fail (object->ref_count >= 1, object);
g_object_ref (object);
was_floating = floating_flag_handler (object, -1);
if (was_floating)
g_object_unref (object);
return object;
}
/**
* g_object_force_floating:
* @object: a #GObject
*
* 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
*/
void
g_object_force_floating (GObject *object)
{
g_return_if_fail (G_IS_OBJECT (object));
g_return_if_fail (object->ref_count >= 1);
floating_flag_handler (object, +1);
}
typedef struct {
GObject *object;
guint n_toggle_refs;
struct {
GToggleNotify notify;
gpointer data;
} toggle_refs[1]; /* flexible array */
} ToggleRefStack;
static void
toggle_refs_notify (GObject *object,
gboolean is_last_ref)
{
ToggleRefStack tstack, *tstackptr;
G_LOCK (toggle_refs_mutex);
tstackptr = g_datalist_id_get_data (&object->qdata, quark_toggle_refs);
tstack = *tstackptr;
G_UNLOCK (toggle_refs_mutex);
/* Reentrancy here is not as tricky as it seems, because a toggle reference
* will only be notified when there is exactly one of them.
*/
g_assert (tstack.n_toggle_refs == 1);
tstack.toggle_refs[0].notify (tstack.toggle_refs[0].data, tstack.object, is_last_ref);
}
/**
* g_object_add_toggle_ref: (skip)
* @object: a #GObject
* @notify: a function to call when this reference is the
* last reference to the object, or is no longer
* the last reference.
* @data: data to pass to @notify
*
* Increases the reference count of the object by one and sets a
* callback to be called when all other references to the object are
* dropped, or when this is already the last reference to the object
* and another reference is established.
*
* This functionality is intended for binding @object to a proxy
* object managed by another memory manager. This is done with two
* paired references: the strong reference added by
* g_object_add_toggle_ref() and a reverse reference to the proxy
* object which is either a strong reference or weak reference.
*
* The setup is that when there are no other references to @object,
* only a weak reference is held in the reverse direction from @object
* 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
* "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
* link is always strong.
*
* Multiple toggle references may be added to the same gobject,
* however if there are multiple toggle references to an object, none
* of them will ever be notified until all but one are removed. For
* this reason, you should only ever use a toggle reference if there
* is important state in the proxy object.
*
* Since: 2.8
*/
void
g_object_add_toggle_ref (GObject *object,
GToggleNotify notify,
gpointer data)
{
ToggleRefStack *tstack;
guint i;
g_return_if_fail (G_IS_OBJECT (object));
g_return_if_fail (notify != NULL);
g_return_if_fail (object->ref_count >= 1);
g_object_ref (object);
G_LOCK (toggle_refs_mutex);
tstack = g_datalist_id_remove_no_notify (&object->qdata, quark_toggle_refs);
if (tstack)
{
i = tstack->n_toggle_refs++;
/* allocate i = tstate->n_toggle_refs - 1 positions beyond the 1 declared
* in tstate->toggle_refs */
tstack = g_realloc (tstack, sizeof (*tstack) + sizeof (tstack->toggle_refs[0]) * i);
}
else
{
tstack = g_renew (ToggleRefStack, NULL, 1);
tstack->object = object;
tstack->n_toggle_refs = 1;
i = 0;
}
/* Set a flag for fast lookup after adding the first toggle reference */
if (tstack->n_toggle_refs == 1)
g_datalist_set_flags (&object->qdata, OBJECT_HAS_TOGGLE_REF_FLAG);
tstack->toggle_refs[i].notify = notify;
tstack->toggle_refs[i].data = data;
g_datalist_id_set_data_full (&object->qdata, quark_toggle_refs, tstack,
(GDestroyNotify)g_free);
G_UNLOCK (toggle_refs_mutex);
}
/**
* g_object_remove_toggle_ref: (skip)
* @object: a #GObject
* @notify: a function to call when this reference is the
* last reference to the object, or is no longer
* the last reference.
* @data: data to pass to @notify
*
* Removes a reference added with g_object_add_toggle_ref(). The
* reference count of the object is decreased by one.
*
* Since: 2.8
*/
void
g_object_remove_toggle_ref (GObject *object,
GToggleNotify notify,
gpointer data)
{
ToggleRefStack *tstack;
gboolean found_one = FALSE;
g_return_if_fail (G_IS_OBJECT (object));
g_return_if_fail (notify != NULL);
G_LOCK (toggle_refs_mutex);
tstack = g_datalist_id_get_data (&object->qdata, quark_toggle_refs);
if (tstack)
{
guint i;
for (i = 0; i < tstack->n_toggle_refs; i++)
if (tstack->toggle_refs[i].notify == notify &&
tstack->toggle_refs[i].data == data)
{
found_one = TRUE;
tstack->n_toggle_refs -= 1;
if (i != tstack->n_toggle_refs)
tstack->toggle_refs[i] = tstack->toggle_refs[tstack->n_toggle_refs];
if (tstack->n_toggle_refs == 0)
g_datalist_unset_flags (&object->qdata, OBJECT_HAS_TOGGLE_REF_FLAG);
break;
}
}
G_UNLOCK (toggle_refs_mutex);
if (found_one)
g_object_unref (object);
else
g_warning ("%s: couldn't find toggle ref %p(%p)", G_STRFUNC, notify, data);
}
/**
* g_object_ref:
* @object: (type GObject.Object): a #GObject
*
* Increases the reference count of @object.
*
* Since GLib 2.56, if `GLIB_VERSION_MAX_ALLOWED` is 2.56 or greater, the type
* of @object will be propagated to the return type (using the GCC typeof()
* extension), so any casting the caller needs to do on the return type must be
* explicit.
*
* Returns: (type GObject.Object) (transfer none): the same @object
*/
gpointer
(g_object_ref) (gpointer _object)
{
GObject *object = _object;
gint old_val;
g_return_val_if_fail (G_IS_OBJECT (object), NULL);
g_return_val_if_fail (object->ref_count > 0, NULL);
old_val = g_atomic_int_add (&object->ref_count, 1);
if (old_val == 1 && OBJECT_HAS_TOGGLE_REF (object))
toggle_refs_notify (object, FALSE);
TRACE (GOBJECT_OBJECT_REF(object,G_TYPE_FROM_INSTANCE(object),old_val));
return object;
}
/**
* g_object_unref:
* @object: (type GObject.Object): a #GObject
*
* Decreases the reference count of @object. When its reference count
* drops to 0, the object is finalized (i.e. its memory is freed).
*
* If the pointer to the #GObject may be reused in future (for example, if it is
* an instance variable of another object), it is recommended to clear the
* pointer to %NULL rather than retain a dangling pointer to a potentially
* invalid #GObject instance. Use g_clear_object() for this.
*/
void
g_object_unref (gpointer _object)
{
GObject *object = _object;
gint old_ref;
g_return_if_fail (G_IS_OBJECT (object));
g_return_if_fail (object->ref_count > 0);
/* 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);
if (old_ref > 1)
{
/* valid if last 2 refs are owned by this call to unref and the toggle_ref */
gboolean has_toggle_ref = OBJECT_HAS_TOGGLE_REF (object);
if (!g_atomic_int_compare_and_exchange ((int *)&object->ref_count, old_ref, old_ref - 1))
goto retry_atomic_decrement1;
TRACE (GOBJECT_OBJECT_UNREF(object,G_TYPE_FROM_INSTANCE(object),old_ref));
/* if we went from 2->1 we need to notify toggle refs if any */
if (old_ref == 2 && has_toggle_ref) /* The last ref being held in this case is owned by the toggle_ref */
toggle_refs_notify (object, TRUE);
}
else
{
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));
/* may have been re-referenced meanwhile */
retry_atomic_decrement2:
old_ref = g_atomic_int_get ((int *)&object->ref_count);
if (old_ref > 1)
{
/* valid if last 2 refs are owned by this call to unref and the toggle_ref */
gboolean has_toggle_ref = OBJECT_HAS_TOGGLE_REF (object);
if (!g_atomic_int_compare_and_exchange ((int *)&object->ref_count, old_ref, old_ref - 1))
goto retry_atomic_decrement2;
TRACE (GOBJECT_OBJECT_UNREF(object,G_TYPE_FROM_INSTANCE(object),old_ref));
/* if we went from 2->1 we need to notify toggle refs if any */
if (old_ref == 2 && has_toggle_ref) /* The last ref being held in this case is owned by the toggle_ref */
toggle_refs_notify (object, TRUE);
return;
}
/* we are still in the process of taking away the last ref */
g_datalist_id_set_data (&object->qdata, quark_closure_array, NULL);
g_signal_handlers_destroy (object);
g_datalist_id_set_data (&object->qdata, quark_weak_refs, NULL);
/* decrement the last reference */
old_ref = g_atomic_int_add (&object->ref_count, -1);
TRACE (GOBJECT_OBJECT_UNREF(object,G_TYPE_FROM_INSTANCE(object),old_ref));
/* may have been re-referenced meanwhile */
if (G_LIKELY (old_ref == 1))
{
TRACE (GOBJECT_OBJECT_FINALIZE(object,G_TYPE_FROM_INSTANCE(object)));
G_OBJECT_GET_CLASS (object)->finalize (object);
TRACE (GOBJECT_OBJECT_FINALIZE_END(object,G_TYPE_FROM_INSTANCE(object)));
GOBJECT_IF_DEBUG (OBJECTS,
{
/* catch objects not chaining finalize handlers */
G_LOCK (debug_objects);
g_assert (!g_hash_table_contains (debug_objects_ht, object));
G_UNLOCK (debug_objects);
});
g_type_free_instance ((GTypeInstance*) object);
}
}
}
/**
* g_clear_object: (skip)
* @object_ptr: a pointer to a #GObject reference
*
* Clears a reference to a #GObject.
*
* @object_ptr must not be %NULL.
*
* If the reference is %NULL then this function does nothing.
* Otherwise, the reference count of the object is decreased and the
* pointer is set to %NULL.
*
* A macro is also included that allows this function to be used without
* pointer casts.
*
* Since: 2.28
**/
#undef g_clear_object
void