1 /* GObject - GLib Type, Object, Parameter and Signal Library
2 * Copyright (C) 1998-1999, 2000-2001 Tim Janik and Red Hat, Inc.
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General
15 * Public License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
17 * Boston, MA 02111-1307, USA.
21 * MT safe with regards to reference counting.
30 #include "gtype-private.h"
31 #include "gvaluecollector.h"
33 #include "gparamspecs.h"
34 #include "gvaluetypes.h"
35 #include "gobject_trace.h"
40 * @short_description: The base object type
41 * @see_also: #GParamSpecObject, g_param_spec_object()
43 * GObject is the fundamental type providing the common attributes and
44 * methods for all object types in GTK+, Pango and other libraries
45 * based on GObject. The GObject class provides methods for object
46 * construction and destruction, property access methods, and signal
47 * support. Signals are described in detail in <xref
48 * linkend="gobject-Signals"/>.
50 * <para id="floating-ref">
51 * GInitiallyUnowned is derived from GObject. The only difference between
52 * the two is that the initial reference of a GInitiallyUnowned is flagged
53 * as a <firstterm>floating</firstterm> reference.
54 * This means that it is not specifically claimed to be "owned" by
55 * any code portion. The main motivation for providing floating references is
56 * C convenience. In particular, it allows code to be written as:
58 * container = create_container ();
59 * container_add_child (container, create_child());
61 * If <function>container_add_child()</function> will g_object_ref_sink() the
62 * passed in child, no reference of the newly created child is leaked.
63 * Without floating references, <function>container_add_child()</function>
64 * can only g_object_ref() the new child, so to implement this code without
65 * reference leaks, it would have to be written as:
68 * container = create_container ();
69 * child = create_child ();
70 * container_add_child (container, child);
71 * g_object_unref (child);
73 * The floating reference can be converted into
74 * an ordinary reference by calling g_object_ref_sink().
75 * For already sunken objects (objects that don't have a floating reference
76 * anymore), g_object_ref_sink() is equivalent to g_object_ref() and returns
78 * Since floating references are useful almost exclusively for C convenience,
79 * language bindings that provide automated reference and memory ownership
80 * maintenance (such as smart pointers or garbage collection) should not
81 * expose floating references in their API.
84 * Some object implementations may need to save an objects floating state
85 * across certain code portions (an example is #GtkMenu), to achieve this,
86 * the following sequence can be used:
89 * /* save floating state */
90 * gboolean was_floating = g_object_is_floating (object);
91 * g_object_ref_sink (object);
92 * /* protected code portion */
94 * /* restore floating state */
96 * g_object_force_floating (object);
97 * g_object_unref (object); /* release previously acquired reference */
103 #define PARAM_SPEC_PARAM_ID(pspec) ((pspec)->param_id)
104 #define PARAM_SPEC_SET_PARAM_ID(pspec, id) ((pspec)->param_id = (id))
106 #define OBJECT_HAS_TOGGLE_REF_FLAG 0x1
107 #define OBJECT_HAS_TOGGLE_REF(object) \
108 ((g_datalist_get_flags (&(object)->qdata) & OBJECT_HAS_TOGGLE_REF_FLAG) != 0)
109 #define OBJECT_FLOATING_FLAG 0x2
111 #define CLASS_HAS_PROPS_FLAG 0x1
112 #define CLASS_HAS_PROPS(class) \
113 ((class)->flags & CLASS_HAS_PROPS_FLAG)
114 #define CLASS_HAS_CUSTOM_CONSTRUCTOR(class) \
115 ((class)->constructor != g_object_constructor)
116 #define CLASS_HAS_CUSTOM_CONSTRUCTED(class) \
117 ((class)->constructed != g_object_constructed)
119 #define CLASS_HAS_DERIVED_CLASS_FLAG 0x2
120 #define CLASS_HAS_DERIVED_CLASS(class) \
121 ((class)->flags & CLASS_HAS_DERIVED_CLASS_FLAG)
123 /* --- signals --- */
130 /* --- properties --- */
136 /* --- prototypes --- */
137 static void g_object_base_class_init (GObjectClass *class);
138 static void g_object_base_class_finalize (GObjectClass *class);
139 static void g_object_do_class_init (GObjectClass *class);
140 static void g_object_init (GObject *object,
141 GObjectClass *class);
142 static GObject* g_object_constructor (GType type,
143 guint n_construct_properties,
144 GObjectConstructParam *construct_params);
145 static void g_object_constructed (GObject *object);
146 static void g_object_real_dispose (GObject *object);
147 static void g_object_finalize (GObject *object);
148 static void g_object_do_set_property (GObject *object,
152 static void g_object_do_get_property (GObject *object,
156 static void g_value_object_init (GValue *value);
157 static void g_value_object_free_value (GValue *value);
158 static void g_value_object_copy_value (const GValue *src_value,
160 static void g_value_object_transform_value (const GValue *src_value,
162 static gpointer g_value_object_peek_pointer (const GValue *value);
163 static gchar* g_value_object_collect_value (GValue *value,
164 guint n_collect_values,
165 GTypeCValue *collect_values,
166 guint collect_flags);
167 static gchar* g_value_object_lcopy_value (const GValue *value,
168 guint n_collect_values,
169 GTypeCValue *collect_values,
170 guint collect_flags);
171 static void g_object_dispatch_properties_changed (GObject *object,
173 GParamSpec **pspecs);
174 static guint object_floating_flag_handler (GObject *object,
177 static void object_interface_check_properties (gpointer func_data,
180 /* --- typedefs --- */
181 typedef struct _GObjectNotifyQueue GObjectNotifyQueue;
183 struct _GObjectNotifyQueue
187 guint16 freeze_count;
190 /* --- variables --- */
191 G_LOCK_DEFINE_STATIC (closure_array_mutex);
192 G_LOCK_DEFINE_STATIC (weak_refs_mutex);
193 G_LOCK_DEFINE_STATIC (toggle_refs_mutex);
194 static GQuark quark_closure_array = 0;
195 static GQuark quark_weak_refs = 0;
196 static GQuark quark_toggle_refs = 0;
197 static GQuark quark_notify_queue;
198 static GParamSpecPool *pspec_pool = NULL;
199 static gulong gobject_signals[LAST_SIGNAL] = { 0, };
200 static guint (*floating_flag_handler) (GObject*, gint) = object_floating_flag_handler;
201 G_LOCK_DEFINE_STATIC (construction_mutex);
202 static GSList *construction_objects = NULL;
204 G_LOCK_DEFINE_STATIC(notify_lock);
206 /* --- functions --- */
208 g_object_notify_queue_free (gpointer data)
210 GObjectNotifyQueue *nqueue = data;
212 g_slist_free (nqueue->pspecs);
213 g_slice_free (GObjectNotifyQueue, nqueue);
216 static GObjectNotifyQueue*
217 g_object_notify_queue_freeze (GObject *object,
218 gboolean conditional)
220 GObjectNotifyQueue *nqueue;
223 nqueue = g_datalist_id_get_data (&object->qdata, quark_notify_queue);
228 G_UNLOCK(notify_lock);
232 nqueue = g_slice_new0 (GObjectNotifyQueue);
233 g_datalist_id_set_data_full (&object->qdata, quark_notify_queue,
234 nqueue, g_object_notify_queue_free);
237 if (nqueue->freeze_count >= 65535)
238 g_critical("Free queue for %s (%p) is larger than 65535,"
239 " called g_object_freeze_notify() too often."
240 " Forgot to call g_object_thaw_notify() or infinite loop",
241 G_OBJECT_TYPE_NAME (object), object);
243 nqueue->freeze_count++;
244 G_UNLOCK(notify_lock);
250 g_object_notify_queue_thaw (GObject *object,
251 GObjectNotifyQueue *nqueue)
253 GParamSpec *pspecs_mem[16], **pspecs, **free_me = NULL;
257 g_return_if_fail (nqueue->freeze_count > 0);
258 g_return_if_fail (g_atomic_int_get(&object->ref_count) > 0);
262 /* Just make sure we never get into some nasty race condition */
263 if (G_UNLIKELY(nqueue->freeze_count == 0)) {
264 G_UNLOCK(notify_lock);
265 g_warning ("%s: property-changed notification for %s(%p) is not frozen",
266 G_STRFUNC, G_OBJECT_TYPE_NAME (object), object);
270 nqueue->freeze_count--;
271 if (nqueue->freeze_count) {
272 G_UNLOCK(notify_lock);
276 pspecs = nqueue->n_pspecs > 16 ? free_me = g_new (GParamSpec*, nqueue->n_pspecs) : pspecs_mem;
278 for (slist = nqueue->pspecs; slist; slist = slist->next)
280 pspecs[n_pspecs++] = slist->data;
282 g_datalist_id_set_data (&object->qdata, quark_notify_queue, NULL);
284 G_UNLOCK(notify_lock);
287 G_OBJECT_GET_CLASS (object)->dispatch_properties_changed (object, n_pspecs, pspecs);
292 g_object_notify_queue_add (GObject *object,
293 GObjectNotifyQueue *nqueue,
298 g_return_if_fail (nqueue->n_pspecs < 65535);
300 if (g_slist_find (nqueue->pspecs, pspec) == NULL)
302 nqueue->pspecs = g_slist_prepend (nqueue->pspecs, pspec);
306 G_UNLOCK(notify_lock);
309 #ifdef G_ENABLE_DEBUG
310 #define IF_DEBUG(debug_type) if (_g_type_debug_flags & G_TYPE_DEBUG_ ## debug_type)
311 G_LOCK_DEFINE_STATIC (debug_objects);
312 static volatile GObject *g_trap_object_ref = NULL;
313 static guint debug_objects_count = 0;
314 static GHashTable *debug_objects_ht = NULL;
317 debug_objects_foreach (gpointer key,
321 GObject *object = value;
323 g_message ("[%p] stale %s\tref_count=%u",
325 G_OBJECT_TYPE_NAME (object),
330 debug_objects_atexit (void)
334 G_LOCK (debug_objects);
335 g_message ("stale GObjects: %u", debug_objects_count);
336 g_hash_table_foreach (debug_objects_ht, debug_objects_foreach, NULL);
337 G_UNLOCK (debug_objects);
340 #endif /* G_ENABLE_DEBUG */
343 _g_object_type_init (void)
345 static gboolean initialized = FALSE;
346 static const GTypeFundamentalInfo finfo = {
347 G_TYPE_FLAG_CLASSED | G_TYPE_FLAG_INSTANTIATABLE | G_TYPE_FLAG_DERIVABLE | G_TYPE_FLAG_DEEP_DERIVABLE,
350 sizeof (GObjectClass),
351 (GBaseInitFunc) g_object_base_class_init,
352 (GBaseFinalizeFunc) g_object_base_class_finalize,
353 (GClassInitFunc) g_object_do_class_init,
354 NULL /* class_destroy */,
355 NULL /* class_data */,
358 (GInstanceInitFunc) g_object_init,
359 NULL, /* value_table */
361 static const GTypeValueTable value_table = {
362 g_value_object_init, /* value_init */
363 g_value_object_free_value, /* value_free */
364 g_value_object_copy_value, /* value_copy */
365 g_value_object_peek_pointer, /* value_peek_pointer */
366 "p", /* collect_format */
367 g_value_object_collect_value, /* collect_value */
368 "p", /* lcopy_format */
369 g_value_object_lcopy_value, /* lcopy_value */
373 g_return_if_fail (initialized == FALSE);
378 info.value_table = &value_table;
379 type = g_type_register_fundamental (G_TYPE_OBJECT, g_intern_static_string ("GObject"), &info, &finfo, 0);
380 g_assert (type == G_TYPE_OBJECT);
381 g_value_register_transform_func (G_TYPE_OBJECT, G_TYPE_OBJECT, g_value_object_transform_value);
383 #ifdef G_ENABLE_DEBUG
386 debug_objects_ht = g_hash_table_new (g_direct_hash, NULL);
387 g_atexit (debug_objects_atexit);
389 #endif /* G_ENABLE_DEBUG */
393 g_object_base_class_init (GObjectClass *class)
395 GObjectClass *pclass = g_type_class_peek_parent (class);
397 /* Don't inherit HAS_DERIVED_CLASS flag from parent class */
398 class->flags &= ~CLASS_HAS_DERIVED_CLASS_FLAG;
401 pclass->flags |= CLASS_HAS_DERIVED_CLASS_FLAG;
403 /* reset instance specific fields and methods that don't get inherited */
404 class->construct_properties = pclass ? g_slist_copy (pclass->construct_properties) : NULL;
405 class->get_property = NULL;
406 class->set_property = NULL;
410 g_object_base_class_finalize (GObjectClass *class)
414 _g_signals_destroy (G_OBJECT_CLASS_TYPE (class));
416 g_slist_free (class->construct_properties);
417 class->construct_properties = NULL;
418 list = g_param_spec_pool_list_owned (pspec_pool, G_OBJECT_CLASS_TYPE (class));
419 for (node = list; node; node = node->next)
421 GParamSpec *pspec = node->data;
423 g_param_spec_pool_remove (pspec_pool, pspec);
424 PARAM_SPEC_SET_PARAM_ID (pspec, 0);
425 g_param_spec_unref (pspec);
431 g_object_do_class_init (GObjectClass *class)
433 /* read the comment about typedef struct CArray; on why not to change this quark */
434 quark_closure_array = g_quark_from_static_string ("GObject-closure-array");
436 quark_weak_refs = g_quark_from_static_string ("GObject-weak-references");
437 quark_toggle_refs = g_quark_from_static_string ("GObject-toggle-references");
438 quark_notify_queue = g_quark_from_static_string ("GObject-notify-queue");
439 pspec_pool = g_param_spec_pool_new (TRUE);
441 class->constructor = g_object_constructor;
442 class->constructed = g_object_constructed;
443 class->set_property = g_object_do_set_property;
444 class->get_property = g_object_do_get_property;
445 class->dispose = g_object_real_dispose;
446 class->finalize = g_object_finalize;
447 class->dispatch_properties_changed = g_object_dispatch_properties_changed;
448 class->notify = NULL;
452 * @gobject: the object which received the signal.
453 * @pspec: the #GParamSpec of the property which changed.
455 * The notify signal is emitted on an object when one of its
456 * properties has been changed. Note that getting this signal
457 * doesn't guarantee that the value of the property has actually
458 * changed, it may also be emitted when the setter for the property
459 * is called to reinstate the previous value.
461 * This signal is typically used to obtain change notification for a
462 * single property, by specifying the property name as a detail in the
463 * g_signal_connect() call, like this:
465 * g_signal_connect (text_view->buffer, "notify::paste-target-list",
466 * G_CALLBACK (gtk_text_view_target_list_notify),
469 * It is important to note that you must use
470 * <link linkend="canonical-parameter-name">canonical</link> parameter names as
471 * detail strings for the notify signal.
473 gobject_signals[NOTIFY] =
474 g_signal_new (g_intern_static_string ("notify"),
475 G_TYPE_FROM_CLASS (class),
476 G_SIGNAL_RUN_FIRST | G_SIGNAL_NO_RECURSE | G_SIGNAL_DETAILED | G_SIGNAL_NO_HOOKS | G_SIGNAL_ACTION,
477 G_STRUCT_OFFSET (GObjectClass, notify),
479 g_cclosure_marshal_VOID__PARAM,
483 /* Install a check function that we'll use to verify that classes that
484 * implement an interface implement all properties for that interface
486 g_type_add_interface_check (NULL, object_interface_check_properties);
490 install_property_internal (GType g_type,
494 if (g_param_spec_pool_lookup (pspec_pool, pspec->name, g_type, FALSE))
496 g_warning ("When installing property: type `%s' already has a property named `%s'",
497 g_type_name (g_type),
502 g_param_spec_ref_sink (pspec);
503 PARAM_SPEC_SET_PARAM_ID (pspec, property_id);
504 g_param_spec_pool_insert (pspec_pool, pspec, g_type);
508 * g_object_class_install_property:
509 * @oclass: a #GObjectClass
510 * @property_id: the id for the new property
511 * @pspec: the #GParamSpec for the new property
513 * Installs a new property. This is usually done in the class initializer.
515 * Note that it is possible to redefine a property in a derived class,
516 * by installing a property with the same name. This can be useful at times,
517 * e.g. to change the range of allowed values or the default value.
520 g_object_class_install_property (GObjectClass *class,
524 g_return_if_fail (G_IS_OBJECT_CLASS (class));
525 g_return_if_fail (G_IS_PARAM_SPEC (pspec));
527 if (CLASS_HAS_DERIVED_CLASS (class))
528 g_error ("Attempt to add property %s::%s to class after it was derived",
529 G_OBJECT_CLASS_NAME (class), pspec->name);
531 class->flags |= CLASS_HAS_PROPS_FLAG;
533 g_return_if_fail (pspec->flags & (G_PARAM_READABLE | G_PARAM_WRITABLE));
534 if (pspec->flags & G_PARAM_WRITABLE)
535 g_return_if_fail (class->set_property != NULL);
536 if (pspec->flags & G_PARAM_READABLE)
537 g_return_if_fail (class->get_property != NULL);
538 g_return_if_fail (property_id > 0);
539 g_return_if_fail (PARAM_SPEC_PARAM_ID (pspec) == 0); /* paranoid */
540 if (pspec->flags & G_PARAM_CONSTRUCT)
541 g_return_if_fail ((pspec->flags & G_PARAM_CONSTRUCT_ONLY) == 0);
542 if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))
543 g_return_if_fail (pspec->flags & G_PARAM_WRITABLE);
545 install_property_internal (G_OBJECT_CLASS_TYPE (class), property_id, pspec);
547 if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))
548 class->construct_properties = g_slist_prepend (class->construct_properties, pspec);
550 /* for property overrides of construct properties, we have to get rid
551 * of the overidden inherited construct property
553 pspec = g_param_spec_pool_lookup (pspec_pool, pspec->name, g_type_parent (G_OBJECT_CLASS_TYPE (class)), TRUE);
554 if (pspec && pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))
555 class->construct_properties = g_slist_remove (class->construct_properties, pspec);
559 * g_object_class_install_properties:
560 * @oclass: a #GObjectClass
561 * @n_pspecs: the length of the #GParamSpec<!-- -->s array
562 * @pspecs: (array length=n_pspecs): the #GParamSpec<!-- -->s array
563 * defining the new properties
565 * Installs new properties from an array of #GParamSpec<!-- -->s. This is
566 * usually done in the class initializer.
568 * The property id of each property is the index of each #GParamSpec in
571 * The property id of 0 is treated specially by #GObject and it should not
572 * be used to store a #GParamSpec.
574 * This function should be used if you plan to use a static array of
575 * #GParamSpec<!-- -->s and g_object_notify_by_pspec(). For instance, this
576 * class initialization:
580 * PROP_0, PROP_FOO, PROP_BAR, N_PROPERTIES
583 * static GParamSpec *obj_properties[N_PROPERTIES] = { NULL, };
586 * my_object_class_init (MyObjectClass *klass)
588 * GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
590 * obj_properties[PROP_FOO] =
591 * g_param_spec_int ("foo", "Foo", "Foo",
594 * G_PARAM_READWRITE);
596 * obj_properties[PROP_BAR] =
597 * g_param_spec_string ("bar", "Bar", "Bar",
599 * G_PARAM_READWRITE);
601 * gobject_class->set_property = my_object_set_property;
602 * gobject_class->get_property = my_object_get_property;
603 * g_object_class_install_properties (gobject_class,
609 * allows calling g_object_notify_by_pspec() to notify of property changes:
613 * my_object_set_foo (MyObject *self, gint foo)
615 * if (self->foo != foo)
618 * g_object_notify_by_pspec (G_OBJECT (self), obj_properties[PROP_FOO]);
626 g_object_class_install_properties (GObjectClass *oclass,
630 GType oclass_type, parent_type;
633 g_return_if_fail (G_IS_OBJECT_CLASS (oclass));
634 g_return_if_fail (n_pspecs > 1);
635 g_return_if_fail (pspecs[0] == NULL);
637 if (CLASS_HAS_DERIVED_CLASS (oclass))
638 g_error ("Attempt to add properties to %s after it was derived",
639 G_OBJECT_CLASS_NAME (oclass));
641 oclass_type = G_OBJECT_CLASS_TYPE (oclass);
642 parent_type = g_type_parent (oclass_type);
644 /* we skip the first element of the array as it would have a 0 prop_id */
645 for (i = 1; i < n_pspecs; i++)
647 GParamSpec *pspec = pspecs[i];
649 g_return_if_fail (pspec != NULL);
651 if (pspec->flags & G_PARAM_WRITABLE)
652 g_return_if_fail (oclass->set_property != NULL);
653 if (pspec->flags & G_PARAM_READABLE)
654 g_return_if_fail (oclass->get_property != NULL);
655 g_return_if_fail (PARAM_SPEC_PARAM_ID (pspec) == 0); /* paranoid */
656 if (pspec->flags & G_PARAM_CONSTRUCT)
657 g_return_if_fail ((pspec->flags & G_PARAM_CONSTRUCT_ONLY) == 0);
658 if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))
659 g_return_if_fail (pspec->flags & G_PARAM_WRITABLE);
661 oclass->flags |= CLASS_HAS_PROPS_FLAG;
662 install_property_internal (oclass_type, i, pspec);
664 if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))
665 oclass->construct_properties = g_slist_prepend (oclass->construct_properties, pspec);
667 /* for property overrides of construct properties, we have to get rid
668 * of the overidden inherited construct property
670 pspec = g_param_spec_pool_lookup (pspec_pool, pspec->name, parent_type, TRUE);
671 if (pspec && pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))
672 oclass->construct_properties = g_slist_remove (oclass->construct_properties, pspec);
677 * g_object_interface_install_property:
678 * @g_iface: any interface vtable for the interface, or the default
679 * vtable for the interface.
680 * @pspec: the #GParamSpec for the new property
682 * Add a property to an interface; this is only useful for interfaces
683 * that are added to GObject-derived types. Adding a property to an
684 * interface forces all objects classes with that interface to have a
685 * compatible property. The compatible property could be a newly
686 * created #GParamSpec, but normally
687 * g_object_class_override_property() will be used so that the object
688 * class only needs to provide an implementation and inherits the
689 * property description, default value, bounds, and so forth from the
690 * interface property.
692 * This function is meant to be called from the interface's default
693 * vtable initialization function (the @class_init member of
694 * #GTypeInfo.) It must not be called after after @class_init has
695 * been called for any object types implementing this interface.
700 g_object_interface_install_property (gpointer g_iface,
703 GTypeInterface *iface_class = g_iface;
705 g_return_if_fail (G_TYPE_IS_INTERFACE (iface_class->g_type));
706 g_return_if_fail (G_IS_PARAM_SPEC (pspec));
707 g_return_if_fail (!G_IS_PARAM_SPEC_OVERRIDE (pspec)); /* paranoid */
708 g_return_if_fail (PARAM_SPEC_PARAM_ID (pspec) == 0); /* paranoid */
710 install_property_internal (iface_class->g_type, 0, pspec);
714 * g_object_class_find_property:
715 * @oclass: a #GObjectClass
716 * @property_name: the name of the property to look up
718 * Looks up the #GParamSpec for a property of a class.
720 * Returns: (transfer none): the #GParamSpec for the property, or
721 * %NULL if the class doesn't have a property of that name
724 g_object_class_find_property (GObjectClass *class,
725 const gchar *property_name)
728 GParamSpec *redirect;
730 g_return_val_if_fail (G_IS_OBJECT_CLASS (class), NULL);
731 g_return_val_if_fail (property_name != NULL, NULL);
733 pspec = g_param_spec_pool_lookup (pspec_pool,
735 G_OBJECT_CLASS_TYPE (class),
739 redirect = g_param_spec_get_redirect_target (pspec);
750 * g_object_interface_find_property:
751 * @g_iface: any interface vtable for the interface, or the default
752 * vtable for the interface
753 * @property_name: name of a property to lookup.
755 * Find the #GParamSpec with the given name for an
756 * interface. Generally, the interface vtable passed in as @g_iface
757 * will be the default vtable from g_type_default_interface_ref(), or,
758 * if you know the interface has already been loaded,
759 * g_type_default_interface_peek().
763 * Returns: (transfer none): the #GParamSpec for the property of the
764 * interface with the name @property_name, or %NULL if no
765 * such property exists.
768 g_object_interface_find_property (gpointer g_iface,
769 const gchar *property_name)
771 GTypeInterface *iface_class = g_iface;
773 g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface_class->g_type), NULL);
774 g_return_val_if_fail (property_name != NULL, NULL);
776 return g_param_spec_pool_lookup (pspec_pool,
783 * g_object_class_override_property:
784 * @oclass: a #GObjectClass
785 * @property_id: the new property ID
786 * @name: the name of a property registered in a parent class or
787 * in an interface of this class.
789 * Registers @property_id as referring to a property with the
790 * name @name in a parent class or in an interface implemented
791 * by @oclass. This allows this class to <firstterm>override</firstterm>
792 * a property implementation in a parent class or to provide
793 * the implementation of a property from an interface.
796 * Internally, overriding is implemented by creating a property of type
797 * #GParamSpecOverride; generally operations that query the properties of
798 * the object class, such as g_object_class_find_property() or
799 * g_object_class_list_properties() will return the overridden
800 * property. However, in one case, the @construct_properties argument of
801 * the @constructor virtual function, the #GParamSpecOverride is passed
802 * instead, so that the @param_id field of the #GParamSpec will be
803 * correct. For virtually all uses, this makes no difference. If you
804 * need to get the overridden property, you can call
805 * g_param_spec_get_redirect_target().
811 g_object_class_override_property (GObjectClass *oclass,
815 GParamSpec *overridden = NULL;
819 g_return_if_fail (G_IS_OBJECT_CLASS (oclass));
820 g_return_if_fail (property_id > 0);
821 g_return_if_fail (name != NULL);
823 /* Find the overridden property; first check parent types
825 parent_type = g_type_parent (G_OBJECT_CLASS_TYPE (oclass));
826 if (parent_type != G_TYPE_NONE)
827 overridden = g_param_spec_pool_lookup (pspec_pool,
836 /* Now check interfaces
838 ifaces = g_type_interfaces (G_OBJECT_CLASS_TYPE (oclass), &n_ifaces);
839 while (n_ifaces-- && !overridden)
841 overridden = g_param_spec_pool_lookup (pspec_pool,
852 g_warning ("%s: Can't find property to override for '%s::%s'",
853 G_STRFUNC, G_OBJECT_CLASS_NAME (oclass), name);
857 new = g_param_spec_override (name, overridden);
858 g_object_class_install_property (oclass, property_id, new);
862 * g_object_class_list_properties:
863 * @oclass: a #GObjectClass
864 * @n_properties: (out): return location for the length of the returned array
866 * Get an array of #GParamSpec* for all properties of a class.
868 * Returns: (array length=n_properties) (transfer container): an array of
869 * #GParamSpec* which should be freed after use
871 GParamSpec** /* free result */
872 g_object_class_list_properties (GObjectClass *class,
873 guint *n_properties_p)
878 g_return_val_if_fail (G_IS_OBJECT_CLASS (class), NULL);
880 pspecs = g_param_spec_pool_list (pspec_pool,
881 G_OBJECT_CLASS_TYPE (class),
890 * g_object_interface_list_properties:
891 * @g_iface: any interface vtable for the interface, or the default
892 * vtable for the interface
893 * @n_properties_p: (out): location to store number of properties returned.
895 * Lists the properties of an interface.Generally, the interface
896 * vtable passed in as @g_iface will be the default vtable from
897 * g_type_default_interface_ref(), or, if you know the interface has
898 * already been loaded, g_type_default_interface_peek().
902 * Returns: (array length=n_properties_p) (transfer container): a
903 * pointer to an array of pointers to #GParamSpec
904 * structures. The paramspecs are owned by GLib, but the
905 * array should be freed with g_free() when you are done with
909 g_object_interface_list_properties (gpointer g_iface,
910 guint *n_properties_p)
912 GTypeInterface *iface_class = g_iface;
916 g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface_class->g_type), NULL);
918 pspecs = g_param_spec_pool_list (pspec_pool,
928 g_object_init (GObject *object,
931 object->ref_count = 1;
932 object->qdata = NULL;
934 if (CLASS_HAS_PROPS (class))
936 /* freeze object's notification queue, g_object_newv() preserves pairedness */
937 g_object_notify_queue_freeze (object, FALSE);
940 if (CLASS_HAS_CUSTOM_CONSTRUCTOR (class))
942 /* enter construction list for notify_queue_thaw() and to allow construct-only properties */
943 G_LOCK (construction_mutex);
944 construction_objects = g_slist_prepend (construction_objects, object);
945 G_UNLOCK (construction_mutex);
948 #ifdef G_ENABLE_DEBUG
951 G_LOCK (debug_objects);
952 debug_objects_count++;
953 g_hash_table_insert (debug_objects_ht, object, object);
954 G_UNLOCK (debug_objects);
956 #endif /* G_ENABLE_DEBUG */
960 g_object_do_set_property (GObject *object,
968 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
974 g_object_do_get_property (GObject *object,
982 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
988 g_object_real_dispose (GObject *object)
990 g_signal_handlers_destroy (object);
991 g_datalist_id_set_data (&object->qdata, quark_closure_array, NULL);
992 g_datalist_id_set_data (&object->qdata, quark_weak_refs, NULL);
996 g_object_finalize (GObject *object)
998 g_datalist_clear (&object->qdata);
1000 #ifdef G_ENABLE_DEBUG
1003 G_LOCK (debug_objects);
1004 g_assert (g_hash_table_lookup (debug_objects_ht, object) == object);
1005 g_hash_table_remove (debug_objects_ht, object);
1006 debug_objects_count--;
1007 G_UNLOCK (debug_objects);
1009 #endif /* G_ENABLE_DEBUG */
1014 g_object_dispatch_properties_changed (GObject *object,
1016 GParamSpec **pspecs)
1020 for (i = 0; i < n_pspecs; i++)
1021 g_signal_emit (object, gobject_signals[NOTIFY], g_quark_from_string (pspecs[i]->name), pspecs[i]);
1025 * g_object_run_dispose:
1026 * @object: a #GObject
1028 * Releases all references to other objects. This can be used to break
1031 * This functions should only be called from object system implementations.
1034 g_object_run_dispose (GObject *object)
1036 g_return_if_fail (G_IS_OBJECT (object));
1037 g_return_if_fail (object->ref_count > 0);
1039 g_object_ref (object);
1040 TRACE (GOBJECT_OBJECT_DISPOSE(object,G_TYPE_FROM_INSTANCE(object), 0));
1041 G_OBJECT_GET_CLASS (object)->dispose (object);
1042 TRACE (GOBJECT_OBJECT_DISPOSE_END(object,G_TYPE_FROM_INSTANCE(object), 0));
1043 g_object_unref (object);
1047 * g_object_freeze_notify:
1048 * @object: a #GObject
1050 * Increases the freeze count on @object. If the freeze count is
1051 * non-zero, the emission of "notify" signals on @object is
1052 * stopped. The signals are queued until the freeze count is decreased
1055 * This is necessary for accessors that modify multiple properties to prevent
1056 * premature notification while the object is still being modified.
1059 g_object_freeze_notify (GObject *object)
1061 g_return_if_fail (G_IS_OBJECT (object));
1063 if (g_atomic_int_get (&object->ref_count) == 0)
1066 g_object_ref (object);
1067 g_object_notify_queue_freeze (object, FALSE);
1068 g_object_unref (object);
1072 get_notify_pspec (GParamSpec *pspec)
1074 GParamSpec *redirected;
1076 /* we don't notify on non-READABLE parameters */
1077 if (~pspec->flags & G_PARAM_READABLE)
1080 /* if the paramspec is redirected, notify on the target */
1081 redirected = g_param_spec_get_redirect_target (pspec);
1082 if (redirected != NULL)
1085 /* else, notify normally */
1090 g_object_notify_by_spec_internal (GObject *object,
1093 GParamSpec *notify_pspec;
1095 notify_pspec = get_notify_pspec (pspec);
1097 if (notify_pspec != NULL)
1099 GObjectNotifyQueue *nqueue;
1101 /* conditional freeze: only increase freeze count if already frozen */
1102 nqueue = g_object_notify_queue_freeze (object, TRUE);
1106 /* we're frozen, so add to the queue and release our freeze */
1107 g_object_notify_queue_add (object, nqueue, notify_pspec);
1108 g_object_notify_queue_thaw (object, nqueue);
1111 /* not frozen, so just dispatch the notification directly */
1112 G_OBJECT_GET_CLASS (object)
1113 ->dispatch_properties_changed (object, 1, ¬ify_pspec);
1119 * @object: a #GObject
1120 * @property_name: the name of a property installed on the class of @object.
1122 * Emits a "notify" signal for the property @property_name on @object.
1124 * When possible, eg. when signaling a property change from within the class
1125 * that registered the property, you should use g_object_notify_by_pspec()
1129 g_object_notify (GObject *object,
1130 const gchar *property_name)
1134 g_return_if_fail (G_IS_OBJECT (object));
1135 g_return_if_fail (property_name != NULL);
1136 if (g_atomic_int_get (&object->ref_count) == 0)
1139 g_object_ref (object);
1140 /* We don't need to get the redirect target
1141 * (by, e.g. calling g_object_class_find_property())
1142 * because g_object_notify_queue_add() does that
1144 pspec = g_param_spec_pool_lookup (pspec_pool,
1146 G_OBJECT_TYPE (object),
1150 g_warning ("%s: object class `%s' has no property named `%s'",
1152 G_OBJECT_TYPE_NAME (object),
1155 g_object_notify_by_spec_internal (object, pspec);
1156 g_object_unref (object);
1160 * g_object_notify_by_pspec:
1161 * @object: a #GObject
1162 * @pspec: the #GParamSpec of a property installed on the class of @object.
1164 * Emits a "notify" signal for the property specified by @pspec on @object.
1166 * This function omits the property name lookup, hence it is faster than
1167 * g_object_notify().
1169 * One way to avoid using g_object_notify() from within the
1170 * class that registered the properties, and using g_object_notify_by_pspec()
1171 * instead, is to store the GParamSpec used with
1172 * g_object_class_install_property() inside a static array, e.g.:
1182 * static GParamSpec *properties[PROP_LAST];
1185 * my_object_class_init (MyObjectClass *klass)
1187 * properties[PROP_FOO] = g_param_spec_int ("foo", "Foo", "The foo",
1190 * G_PARAM_READWRITE);
1191 * g_object_class_install_property (gobject_class,
1193 * properties[PROP_FOO]);
1197 * and then notify a change on the "foo" property with:
1200 * g_object_notify_by_pspec (self, properties[PROP_FOO]);
1206 g_object_notify_by_pspec (GObject *object,
1210 g_return_if_fail (G_IS_OBJECT (object));
1211 g_return_if_fail (G_IS_PARAM_SPEC (pspec));
1213 g_object_ref (object);
1214 g_object_notify_by_spec_internal (object, pspec);
1215 g_object_unref (object);
1219 * g_object_thaw_notify:
1220 * @object: a #GObject
1222 * Reverts the effect of a previous call to
1223 * g_object_freeze_notify(). The freeze count is decreased on @object
1224 * and when it reaches zero, all queued "notify" signals are emitted.
1226 * It is an error to call this function when the freeze count is zero.
1229 g_object_thaw_notify (GObject *object)
1231 GObjectNotifyQueue *nqueue;
1233 g_return_if_fail (G_IS_OBJECT (object));
1234 if (g_atomic_int_get (&object->ref_count) == 0)
1237 g_object_ref (object);
1239 /* FIXME: Freezing is the only way to get at the notify queue.
1240 * So we freeze once and then thaw twice.
1242 nqueue = g_object_notify_queue_freeze (object, FALSE);
1243 g_object_notify_queue_thaw (object, nqueue);
1244 g_object_notify_queue_thaw (object, nqueue);
1246 g_object_unref (object);
1250 object_get_property (GObject *object,
1254 GObjectClass *class = g_type_class_peek (pspec->owner_type);
1255 guint param_id = PARAM_SPEC_PARAM_ID (pspec);
1256 GParamSpec *redirect;
1260 g_warning ("'%s::%s' is not a valid property name; '%s' is not a GObject subtype",
1261 g_type_name (pspec->owner_type), pspec->name, g_type_name (pspec->owner_type));
1265 redirect = g_param_spec_get_redirect_target (pspec);
1269 class->get_property (object, param_id, value, pspec);
1273 object_set_property (GObject *object,
1275 const GValue *value,
1276 GObjectNotifyQueue *nqueue)
1278 GValue tmp_value = G_VALUE_INIT;
1279 GObjectClass *class = g_type_class_peek (pspec->owner_type);
1280 guint param_id = PARAM_SPEC_PARAM_ID (pspec);
1281 GParamSpec *redirect;
1282 static const gchar * enable_diagnostic = NULL;
1286 g_warning ("'%s::%s' is not a valid property name; '%s' is not a GObject subtype",
1287 g_type_name (pspec->owner_type), pspec->name, g_type_name (pspec->owner_type));
1291 redirect = g_param_spec_get_redirect_target (pspec);
1295 if (G_UNLIKELY (!enable_diagnostic))
1297 enable_diagnostic = g_getenv ("G_ENABLE_DIAGNOSTIC");
1298 if (!enable_diagnostic)
1299 enable_diagnostic = "0";
1302 if (enable_diagnostic[0] == '1')
1304 if (pspec->flags & G_PARAM_DEPRECATED)
1305 g_warning ("The property %s:%s is deprecated and shouldn't be used "
1306 "anymore. It will be removed in a future version.",
1307 G_OBJECT_TYPE_NAME (object), pspec->name);
1310 /* provide a copy to work from, convert (if necessary) and validate */
1311 g_value_init (&tmp_value, pspec->value_type);
1312 if (!g_value_transform (value, &tmp_value))
1313 g_warning ("unable to set property `%s' of type `%s' from value of type `%s'",
1315 g_type_name (pspec->value_type),
1316 G_VALUE_TYPE_NAME (value));
1317 else if (g_param_value_validate (pspec, &tmp_value) && !(pspec->flags & G_PARAM_LAX_VALIDATION))
1319 gchar *contents = g_strdup_value_contents (value);
1321 g_warning ("value \"%s\" of type `%s' is invalid or out of range for property `%s' of type `%s'",
1323 G_VALUE_TYPE_NAME (value),
1325 g_type_name (pspec->value_type));
1330 GParamSpec *notify_pspec;
1332 class->set_property (object, param_id, &tmp_value, pspec);
1334 notify_pspec = get_notify_pspec (pspec);
1336 if (notify_pspec != NULL)
1337 g_object_notify_queue_add (object, nqueue, notify_pspec);
1339 g_value_unset (&tmp_value);
1343 object_interface_check_properties (gpointer func_data,
1346 GTypeInterface *iface_class = g_iface;
1347 GObjectClass *class;
1348 GType iface_type = iface_class->g_type;
1349 GParamSpec **pspecs;
1352 class = g_type_class_ref (iface_class->g_instance_type);
1354 if (!G_IS_OBJECT_CLASS (class))
1357 pspecs = g_param_spec_pool_list (pspec_pool, iface_type, &n);
1361 GParamSpec *class_pspec = g_param_spec_pool_lookup (pspec_pool,
1363 G_OBJECT_CLASS_TYPE (class),
1368 g_critical ("Object class %s doesn't implement property "
1369 "'%s' from interface '%s'",
1370 g_type_name (G_OBJECT_CLASS_TYPE (class)),
1372 g_type_name (iface_type));
1377 /* We do a number of checks on the properties of an interface to
1378 * make sure that all classes implementing the interface are
1379 * overriding the properties in a sane way.
1381 * We do the checks in order of importance so that we can give
1382 * more useful error messages first.
1384 * First, we check that the implementation doesn't remove the
1385 * basic functionality (readability, writability) advertised by
1386 * the interface. Next, we check that it doesn't introduce
1387 * additional restrictions (such as construct-only). Finally, we
1388 * make sure the types are compatible.
1391 #define SUBSET(a,b,mask) (((a) & ~(b) & (mask)) == 0)
1392 /* If the property on the interface is readable then the
1393 * implementation must be readable. If the interface is writable
1394 * then the implementation must be writable.
1396 if (!SUBSET (pspecs[n]->flags, class_pspec->flags, G_PARAM_READABLE | G_PARAM_WRITABLE))
1398 g_critical ("Flags for property '%s' on class '%s' remove functionality compared with the "
1399 "property on interface '%s'\n", pspecs[n]->name,
1400 g_type_name (G_OBJECT_CLASS_TYPE (class)), g_type_name (iface_type));
1404 /* If the property on the interface is writable then we need to
1405 * make sure the implementation doesn't introduce new restrictions
1406 * on that writability (ie: construct-only).
1408 * If the interface was not writable to begin with then we don't
1409 * really have any problems here because "writable at construct
1410 * type only" is still more permissive than "read only".
1412 if (pspecs[n]->flags & G_PARAM_WRITABLE)
1414 if (!SUBSET (class_pspec->flags, pspecs[n]->flags, G_PARAM_CONSTRUCT_ONLY))
1416 g_critical ("Flags for property '%s' on class '%s' introduce additional restrictions on "
1417 "writability compared with the property on interface '%s'\n", pspecs[n]->name,
1418 g_type_name (G_OBJECT_CLASS_TYPE (class)), g_type_name (iface_type));
1424 /* If the property on the interface is readable then we are
1425 * effectively advertising that reading the property will return a
1426 * value of a specific type. All implementations of the interface
1427 * need to return items of this type -- but may be more
1428 * restrictive. For example, it is legal to have:
1430 * GtkWidget *get_item();
1432 * that is implemented by a function that always returns a
1433 * GtkEntry. In short: readability implies that the
1434 * implementation value type must be equal or more restrictive.
1436 * Similarly, if the property on the interface is writable then
1437 * must be able to accept the property being set to any value of
1438 * that type, including subclasses. In this case, we may also be
1439 * less restrictive. For example, it is legal to have:
1441 * set_item (GtkEntry *);
1443 * that is implemented by a function that will actually work with
1444 * any GtkWidget. In short: writability implies that the
1445 * implementation value type must be equal or less restrictive.
1447 * In the case that the property is both readable and writable
1448 * then the only way that both of the above can be satisfied is
1449 * with a type that is exactly equal.
1451 switch (pspecs[n]->flags & (G_PARAM_READABLE | G_PARAM_WRITABLE))
1453 case G_PARAM_READABLE | G_PARAM_WRITABLE:
1454 /* class pspec value type must have exact equality with interface */
1455 if (pspecs[n]->value_type != class_pspec->value_type)
1456 g_critical ("Read/writable property '%s' on class '%s' has type '%s' which is not exactly equal to the "
1457 "type '%s' of the property on the interface '%s'\n", pspecs[n]->name,
1458 g_type_name (G_OBJECT_CLASS_TYPE (class)), g_type_name (G_PARAM_SPEC_VALUE_TYPE (class_pspec)),
1459 g_type_name (G_PARAM_SPEC_VALUE_TYPE (pspecs[n])), g_type_name (iface_type));
1462 case G_PARAM_READABLE:
1463 /* class pspec value type equal or more restrictive than interface */
1464 if (!g_type_is_a (class_pspec->value_type, pspecs[n]->value_type))
1465 g_critical ("Read-only property '%s' on class '%s' has type '%s' which is not equal to or more "
1466 "restrictive than the type '%s' of the property on the interface '%s'\n", pspecs[n]->name,
1467 g_type_name (G_OBJECT_CLASS_TYPE (class)), g_type_name (G_PARAM_SPEC_VALUE_TYPE (class_pspec)),
1468 g_type_name (G_PARAM_SPEC_VALUE_TYPE (pspecs[n])), g_type_name (iface_type));
1471 case G_PARAM_WRITABLE:
1472 /* class pspec value type equal or less restrictive than interface */
1473 if (!g_type_is_a (pspecs[n]->value_type, class_pspec->value_type))
1474 g_critical ("Write-only property '%s' on class '%s' has type '%s' which is not equal to or less "
1475 "restrictive than the type '%s' of the property on the interface '%s' \n", pspecs[n]->name,
1476 g_type_name (G_OBJECT_CLASS_TYPE (class)), g_type_name (G_PARAM_SPEC_VALUE_TYPE (class_pspec)),
1477 g_type_name (G_PARAM_SPEC_VALUE_TYPE (pspecs[n])), g_type_name (iface_type));
1481 g_assert_not_reached ();
1487 g_type_class_unref (class);
1491 g_object_get_type (void)
1493 return G_TYPE_OBJECT;
1497 * g_object_new: (skip)
1498 * @object_type: the type id of the #GObject subtype to instantiate
1499 * @first_property_name: the name of the first property
1500 * @...: the value of the first property, followed optionally by more
1501 * name/value pairs, followed by %NULL
1503 * Creates a new instance of a #GObject subtype and sets its properties.
1505 * Construction parameters (see #G_PARAM_CONSTRUCT, #G_PARAM_CONSTRUCT_ONLY)
1506 * which are not explicitly specified are set to their default values.
1508 * Returns: (transfer full): a new instance of @object_type
1511 g_object_new (GType object_type,
1512 const gchar *first_property_name,
1518 g_return_val_if_fail (G_TYPE_IS_OBJECT (object_type), NULL);
1520 /* short circuit for calls supplying no properties */
1521 if (!first_property_name)
1522 return g_object_newv (object_type, 0, NULL);
1524 va_start (var_args, first_property_name);
1525 object = g_object_new_valist (object_type, first_property_name, var_args);
1532 slist_maybe_remove (GSList **slist,
1535 GSList *last = NULL, *node = *slist;
1538 if (node->data == data)
1541 last->next = node->next;
1543 *slist = node->next;
1544 g_slist_free_1 (node);
1553 static inline gboolean
1554 object_in_construction_list (GObject *object)
1556 gboolean in_construction;
1557 G_LOCK (construction_mutex);
1558 in_construction = g_slist_find (construction_objects, object) != NULL;
1559 G_UNLOCK (construction_mutex);
1560 return in_construction;
1565 * @object_type: the type id of the #GObject subtype to instantiate
1566 * @n_parameters: the length of the @parameters array
1567 * @parameters: (array length=n_parameters): an array of #GParameter
1569 * Creates a new instance of a #GObject subtype and sets its properties.
1571 * Construction parameters (see #G_PARAM_CONSTRUCT, #G_PARAM_CONSTRUCT_ONLY)
1572 * which are not explicitly specified are set to their default values.
1574 * Rename to: g_object_new
1575 * Returns: (type GObject.Object) (transfer full): a new instance of
1579 g_object_newv (GType object_type,
1581 GParameter *parameters)
1583 GObjectConstructParam *cparams = NULL, *oparams;
1584 GObjectNotifyQueue *nqueue = NULL; /* shouldn't be initialized, just to silence compiler */
1586 GObjectClass *class, *unref_class = NULL;
1588 guint n_total_cparams = 0, n_cparams = 0, n_oparams = 0, n_cvalues;
1590 GList *clist = NULL;
1591 gboolean newly_constructed;
1594 g_return_val_if_fail (G_TYPE_IS_OBJECT (object_type), NULL);
1596 class = g_type_class_peek_static (object_type);
1598 class = unref_class = g_type_class_ref (object_type);
1599 for (slist = class->construct_properties; slist; slist = slist->next)
1601 clist = g_list_prepend (clist, slist->data);
1602 n_total_cparams += 1;
1605 if (n_parameters == 0 && n_total_cparams == 0)
1607 /* This is a simple object with no construct properties, and
1608 * no properties are being set, so short circuit the parameter
1609 * handling. This speeds up simple object construction.
1612 object = class->constructor (object_type, 0, NULL);
1613 goto did_construction;
1616 /* collect parameters, sort into construction and normal ones */
1617 oparams = g_new (GObjectConstructParam, n_parameters);
1618 cparams = g_new (GObjectConstructParam, n_total_cparams);
1619 for (i = 0; i < n_parameters; i++)
1621 GValue *value = ¶meters[i].value;
1622 GParamSpec *pspec = g_param_spec_pool_lookup (pspec_pool,
1628 g_warning ("%s: object class `%s' has no property named `%s'",
1630 g_type_name (object_type),
1631 parameters[i].name);
1634 if (!(pspec->flags & G_PARAM_WRITABLE))
1636 g_warning ("%s: property `%s' of object class `%s' is not writable",
1639 g_type_name (object_type));
1642 if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))
1644 GList *list = g_list_find (clist, pspec);
1648 g_warning ("%s: construct property \"%s\" for object `%s' can't be set twice",
1649 G_STRFUNC, pspec->name, g_type_name (object_type));
1652 cparams[n_cparams].pspec = pspec;
1653 cparams[n_cparams].value = value;
1658 list->prev->next = list->next;
1660 list->next->prev = list->prev;
1661 g_list_free_1 (list);
1665 oparams[n_oparams].pspec = pspec;
1666 oparams[n_oparams].value = value;
1671 /* set remaining construction properties to default values */
1672 n_cvalues = n_total_cparams - n_cparams;
1673 cvalues = g_new (GValue, n_cvalues);
1676 GList *tmp = clist->next;
1677 GParamSpec *pspec = clist->data;
1678 GValue *value = cvalues + n_total_cparams - n_cparams - 1;
1681 g_value_init (value, pspec->value_type);
1682 g_param_value_set_default (pspec, value);
1684 cparams[n_cparams].pspec = pspec;
1685 cparams[n_cparams].value = value;
1688 g_list_free_1 (clist);
1692 /* construct object from construction parameters */
1693 object = class->constructor (object_type, n_total_cparams, cparams);
1694 /* free construction values */
1697 g_value_unset (cvalues + n_cvalues);
1701 if (CLASS_HAS_CUSTOM_CONSTRUCTOR (class))
1703 /* adjust freeze_count according to g_object_init() and remaining properties */
1704 G_LOCK (construction_mutex);
1705 newly_constructed = slist_maybe_remove (&construction_objects, object);
1706 G_UNLOCK (construction_mutex);
1709 newly_constructed = TRUE;
1711 if (CLASS_HAS_PROPS (class))
1713 if (newly_constructed || n_oparams)
1714 nqueue = g_object_notify_queue_freeze (object, FALSE);
1715 if (newly_constructed)
1716 g_object_notify_queue_thaw (object, nqueue);
1719 /* run 'constructed' handler if there is a custom one */
1720 if (newly_constructed && CLASS_HAS_CUSTOM_CONSTRUCTED (class))
1721 class->constructed (object);
1723 /* set remaining properties */
1724 for (i = 0; i < n_oparams; i++)
1725 object_set_property (object, oparams[i].pspec, oparams[i].value, nqueue);
1728 if (CLASS_HAS_PROPS (class))
1730 /* release our own freeze count and handle notifications */
1731 if (newly_constructed || n_oparams)
1732 g_object_notify_queue_thaw (object, nqueue);
1736 g_type_class_unref (unref_class);
1742 * g_object_new_valist: (skip)
1743 * @object_type: the type id of the #GObject subtype to instantiate
1744 * @first_property_name: the name of the first property
1745 * @var_args: the value of the first property, followed optionally by more
1746 * name/value pairs, followed by %NULL
1748 * Creates a new instance of a #GObject subtype and sets its properties.
1750 * Construction parameters (see #G_PARAM_CONSTRUCT, #G_PARAM_CONSTRUCT_ONLY)
1751 * which are not explicitly specified are set to their default values.
1753 * Returns: a new instance of @object_type
1756 g_object_new_valist (GType object_type,
1757 const gchar *first_property_name,
1760 GObjectClass *class;
1764 guint n_params = 0, n_alloced_params = 16;
1766 g_return_val_if_fail (G_TYPE_IS_OBJECT (object_type), NULL);
1768 if (!first_property_name)
1769 return g_object_newv (object_type, 0, NULL);
1771 class = g_type_class_ref (object_type);
1773 params = g_new0 (GParameter, n_alloced_params);
1774 name = first_property_name;
1777 gchar *error = NULL;
1778 GParamSpec *pspec = g_param_spec_pool_lookup (pspec_pool,
1784 g_warning ("%s: object class `%s' has no property named `%s'",
1786 g_type_name (object_type),
1790 if (n_params >= n_alloced_params)
1792 n_alloced_params += 16;
1793 params = g_renew (GParameter, params, n_alloced_params);
1794 memset (params + n_params, 0, 16 * (sizeof *params));
1796 params[n_params].name = name;
1797 G_VALUE_COLLECT_INIT (¶ms[n_params].value, pspec->value_type,
1798 var_args, 0, &error);
1801 g_warning ("%s: %s", G_STRFUNC, error);
1803 g_value_unset (¶ms[n_params].value);
1807 name = va_arg (var_args, gchar*);
1810 object = g_object_newv (object_type, n_params, params);
1813 g_value_unset (¶ms[n_params].value);
1816 g_type_class_unref (class);
1822 g_object_constructor (GType type,
1823 guint n_construct_properties,
1824 GObjectConstructParam *construct_params)
1829 object = (GObject*) g_type_create_instance (type);
1831 /* set construction parameters */
1832 if (n_construct_properties)
1834 GObjectNotifyQueue *nqueue = g_object_notify_queue_freeze (object, FALSE);
1836 /* set construct properties */
1837 while (n_construct_properties--)
1839 GValue *value = construct_params->value;
1840 GParamSpec *pspec = construct_params->pspec;
1843 object_set_property (object, pspec, value, nqueue);
1845 g_object_notify_queue_thaw (object, nqueue);
1846 /* the notification queue is still frozen from g_object_init(), so
1847 * we don't need to handle it here, g_object_newv() takes
1856 g_object_constructed (GObject *object)
1858 /* empty default impl to allow unconditional upchaining */
1862 * g_object_set_valist: (skip)
1863 * @object: a #GObject
1864 * @first_property_name: name of the first property to set
1865 * @var_args: value for the first property, followed optionally by more
1866 * name/value pairs, followed by %NULL
1868 * Sets properties on an object.
1871 g_object_set_valist (GObject *object,
1872 const gchar *first_property_name,
1875 GObjectNotifyQueue *nqueue;
1878 g_return_if_fail (G_IS_OBJECT (object));
1880 g_object_ref (object);
1881 nqueue = g_object_notify_queue_freeze (object, FALSE);
1883 name = first_property_name;
1886 GValue value = G_VALUE_INIT;
1888 gchar *error = NULL;
1890 pspec = g_param_spec_pool_lookup (pspec_pool,
1892 G_OBJECT_TYPE (object),
1896 g_warning ("%s: object class `%s' has no property named `%s'",
1898 G_OBJECT_TYPE_NAME (object),
1902 if (!(pspec->flags & G_PARAM_WRITABLE))
1904 g_warning ("%s: property `%s' of object class `%s' is not writable",
1907 G_OBJECT_TYPE_NAME (object));
1910 if ((pspec->flags & G_PARAM_CONSTRUCT_ONLY) && !object_in_construction_list (object))
1912 g_warning ("%s: construct property \"%s\" for object `%s' can't be set after construction",
1913 G_STRFUNC, pspec->name, G_OBJECT_TYPE_NAME (object));
1917 G_VALUE_COLLECT_INIT (&value, pspec->value_type, var_args,
1921 g_warning ("%s: %s", G_STRFUNC, error);
1923 g_value_unset (&value);
1927 object_set_property (object, pspec, &value, nqueue);
1928 g_value_unset (&value);
1930 name = va_arg (var_args, gchar*);
1933 g_object_notify_queue_thaw (object, nqueue);
1934 g_object_unref (object);
1938 * g_object_get_valist: (skip)
1939 * @object: a #GObject
1940 * @first_property_name: name of the first property to get
1941 * @var_args: return location for the first property, followed optionally by more
1942 * name/return location pairs, followed by %NULL
1944 * Gets properties of an object.
1946 * In general, a copy is made of the property contents and the caller
1947 * is responsible for freeing the memory in the appropriate manner for
1948 * the type, for instance by calling g_free() or g_object_unref().
1950 * See g_object_get().
1953 g_object_get_valist (GObject *object,
1954 const gchar *first_property_name,
1959 g_return_if_fail (G_IS_OBJECT (object));
1961 g_object_ref (object);
1963 name = first_property_name;
1967 GValue value = G_VALUE_INIT;
1971 pspec = g_param_spec_pool_lookup (pspec_pool,
1973 G_OBJECT_TYPE (object),
1977 g_warning ("%s: object class `%s' has no property named `%s'",
1979 G_OBJECT_TYPE_NAME (object),
1983 if (!(pspec->flags & G_PARAM_READABLE))
1985 g_warning ("%s: property `%s' of object class `%s' is not readable",
1988 G_OBJECT_TYPE_NAME (object));
1992 g_value_init (&value, pspec->value_type);
1994 object_get_property (object, pspec, &value);
1996 G_VALUE_LCOPY (&value, var_args, 0, &error);
1999 g_warning ("%s: %s", G_STRFUNC, error);
2001 g_value_unset (&value);
2005 g_value_unset (&value);
2007 name = va_arg (var_args, gchar*);
2010 g_object_unref (object);
2014 * g_object_set: (skip)
2015 * @object: a #GObject
2016 * @first_property_name: name of the first property to set
2017 * @...: value for the first property, followed optionally by more
2018 * name/value pairs, followed by %NULL
2020 * Sets properties on an object.
2023 g_object_set (gpointer _object,
2024 const gchar *first_property_name,
2027 GObject *object = _object;
2030 g_return_if_fail (G_IS_OBJECT (object));
2032 va_start (var_args, first_property_name);
2033 g_object_set_valist (object, first_property_name, var_args);
2038 * g_object_get: (skip)
2039 * @object: a #GObject
2040 * @first_property_name: name of the first property to get
2041 * @...: return location for the first property, followed optionally by more
2042 * name/return location pairs, followed by %NULL
2044 * Gets properties of an object.
2046 * In general, a copy is made of the property contents and the caller
2047 * is responsible for freeing the memory in the appropriate manner for
2048 * the type, for instance by calling g_free() or g_object_unref().
2051 * <title>Using g_object_get(<!-- -->)</title>
2052 * An example of using g_object_get() to get the contents
2053 * of three properties - one of type #G_TYPE_INT,
2054 * one of type #G_TYPE_STRING, and one of type #G_TYPE_OBJECT:
2060 * g_object_get (my_object,
2061 * "int-property", &intval,
2062 * "str-property", &strval,
2063 * "obj-property", &objval,
2066 * // Do something with intval, strval, objval
2069 * g_object_unref (objval);
2074 g_object_get (gpointer _object,
2075 const gchar *first_property_name,
2078 GObject *object = _object;
2081 g_return_if_fail (G_IS_OBJECT (object));
2083 va_start (var_args, first_property_name);
2084 g_object_get_valist (object, first_property_name, var_args);
2089 * g_object_set_property:
2090 * @object: a #GObject
2091 * @property_name: the name of the property to set
2094 * Sets a property on an object.
2097 g_object_set_property (GObject *object,
2098 const gchar *property_name,
2099 const GValue *value)
2101 GObjectNotifyQueue *nqueue;
2104 g_return_if_fail (G_IS_OBJECT (object));
2105 g_return_if_fail (property_name != NULL);
2106 g_return_if_fail (G_IS_VALUE (value));
2108 g_object_ref (object);
2109 nqueue = g_object_notify_queue_freeze (object, FALSE);
2111 pspec = g_param_spec_pool_lookup (pspec_pool,
2113 G_OBJECT_TYPE (object),
2116 g_warning ("%s: object class `%s' has no property named `%s'",
2118 G_OBJECT_TYPE_NAME (object),
2120 else if (!(pspec->flags & G_PARAM_WRITABLE))
2121 g_warning ("%s: property `%s' of object class `%s' is not writable",
2124 G_OBJECT_TYPE_NAME (object));
2125 else if ((pspec->flags & G_PARAM_CONSTRUCT_ONLY) && !object_in_construction_list (object))
2126 g_warning ("%s: construct property \"%s\" for object `%s' can't be set after construction",
2127 G_STRFUNC, pspec->name, G_OBJECT_TYPE_NAME (object));
2129 object_set_property (object, pspec, value, nqueue);
2131 g_object_notify_queue_thaw (object, nqueue);
2132 g_object_unref (object);
2136 * g_object_get_property:
2137 * @object: a #GObject
2138 * @property_name: the name of the property to get
2139 * @value: return location for the property value
2141 * Gets a property of an object. @value must have been initialized to the
2142 * expected type of the property (or a type to which the expected type can be
2143 * transformed) using g_value_init().
2145 * In general, a copy is made of the property contents and the caller is
2146 * responsible for freeing the memory by calling g_value_unset().
2148 * Note that g_object_get_property() is really intended for language
2149 * bindings, g_object_get() is much more convenient for C programming.
2152 g_object_get_property (GObject *object,
2153 const gchar *property_name,
2158 g_return_if_fail (G_IS_OBJECT (object));
2159 g_return_if_fail (property_name != NULL);
2160 g_return_if_fail (G_IS_VALUE (value));
2162 g_object_ref (object);
2164 pspec = g_param_spec_pool_lookup (pspec_pool,
2166 G_OBJECT_TYPE (object),
2169 g_warning ("%s: object class `%s' has no property named `%s'",
2171 G_OBJECT_TYPE_NAME (object),
2173 else if (!(pspec->flags & G_PARAM_READABLE))
2174 g_warning ("%s: property `%s' of object class `%s' is not readable",
2177 G_OBJECT_TYPE_NAME (object));
2180 GValue *prop_value, tmp_value = G_VALUE_INIT;
2182 /* auto-conversion of the callers value type
2184 if (G_VALUE_TYPE (value) == pspec->value_type)
2186 g_value_reset (value);
2189 else if (!g_value_type_transformable (pspec->value_type, G_VALUE_TYPE (value)))
2191 g_warning ("%s: can't retrieve property `%s' of type `%s' as value of type `%s'",
2192 G_STRFUNC, pspec->name,
2193 g_type_name (pspec->value_type),
2194 G_VALUE_TYPE_NAME (value));
2195 g_object_unref (object);
2200 g_value_init (&tmp_value, pspec->value_type);
2201 prop_value = &tmp_value;
2203 object_get_property (object, pspec, prop_value);
2204 if (prop_value != value)
2206 g_value_transform (prop_value, value);
2207 g_value_unset (&tmp_value);
2211 g_object_unref (object);
2215 * g_object_connect: (skip)
2216 * @object: a #GObject
2217 * @signal_spec: the spec for the first signal
2218 * @...: #GCallback for the first signal, followed by data for the
2219 * first signal, followed optionally by more signal
2220 * spec/callback/data triples, followed by %NULL
2222 * A convenience function to connect multiple signals at once.
2224 * The signal specs expected by this function have the form
2225 * "modifier::signal_name", where modifier can be one of the following:
2228 * <term>signal</term>
2230 * equivalent to <literal>g_signal_connect_data (..., NULL, 0)</literal>
2231 * </para></listitem>
2234 * <term>object_signal</term>
2235 * <term>object-signal</term>
2237 * equivalent to <literal>g_signal_connect_object (..., 0)</literal>
2238 * </para></listitem>
2241 * <term>swapped_signal</term>
2242 * <term>swapped-signal</term>
2244 * equivalent to <literal>g_signal_connect_data (..., NULL, G_CONNECT_SWAPPED)</literal>
2245 * </para></listitem>
2248 * <term>swapped_object_signal</term>
2249 * <term>swapped-object-signal</term>
2251 * equivalent to <literal>g_signal_connect_object (..., G_CONNECT_SWAPPED)</literal>
2252 * </para></listitem>
2255 * <term>signal_after</term>
2256 * <term>signal-after</term>
2258 * equivalent to <literal>g_signal_connect_data (..., NULL, G_CONNECT_AFTER)</literal>
2259 * </para></listitem>
2262 * <term>object_signal_after</term>
2263 * <term>object-signal-after</term>
2265 * equivalent to <literal>g_signal_connect_object (..., G_CONNECT_AFTER)</literal>
2266 * </para></listitem>
2269 * <term>swapped_signal_after</term>
2270 * <term>swapped-signal-after</term>
2272 * equivalent to <literal>g_signal_connect_data (..., NULL, G_CONNECT_SWAPPED | G_CONNECT_AFTER)</literal>
2273 * </para></listitem>
2276 * <term>swapped_object_signal_after</term>
2277 * <term>swapped-object-signal-after</term>
2279 * equivalent to <literal>g_signal_connect_object (..., G_CONNECT_SWAPPED | G_CONNECT_AFTER)</literal>
2280 * </para></listitem>
2285 * menu->toplevel = g_object_connect (g_object_new (GTK_TYPE_WINDOW,
2286 * "type", GTK_WINDOW_POPUP,
2289 * "signal::event", gtk_menu_window_event, menu,
2290 * "signal::size_request", gtk_menu_window_size_request, menu,
2291 * "signal::destroy", gtk_widget_destroyed, &menu->toplevel,
2295 * Returns: (transfer none): @object
2298 g_object_connect (gpointer _object,
2299 const gchar *signal_spec,
2302 GObject *object = _object;
2305 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
2306 g_return_val_if_fail (object->ref_count > 0, object);
2308 va_start (var_args, signal_spec);
2311 GCallback callback = va_arg (var_args, GCallback);
2312 gpointer data = va_arg (var_args, gpointer);
2314 if (strncmp (signal_spec, "signal::", 8) == 0)
2315 g_signal_connect_data (object, signal_spec + 8,
2316 callback, data, NULL,
2318 else if (strncmp (signal_spec, "object_signal::", 15) == 0 ||
2319 strncmp (signal_spec, "object-signal::", 15) == 0)
2320 g_signal_connect_object (object, signal_spec + 15,
2323 else if (strncmp (signal_spec, "swapped_signal::", 16) == 0 ||
2324 strncmp (signal_spec, "swapped-signal::", 16) == 0)
2325 g_signal_connect_data (object, signal_spec + 16,
2326 callback, data, NULL,
2328 else if (strncmp (signal_spec, "swapped_object_signal::", 23) == 0 ||
2329 strncmp (signal_spec, "swapped-object-signal::", 23) == 0)
2330 g_signal_connect_object (object, signal_spec + 23,
2333 else if (strncmp (signal_spec, "signal_after::", 14) == 0 ||
2334 strncmp (signal_spec, "signal-after::", 14) == 0)
2335 g_signal_connect_data (object, signal_spec + 14,
2336 callback, data, NULL,
2338 else if (strncmp (signal_spec, "object_signal_after::", 21) == 0 ||
2339 strncmp (signal_spec, "object-signal-after::", 21) == 0)
2340 g_signal_connect_object (object, signal_spec + 21,
2343 else if (strncmp (signal_spec, "swapped_signal_after::", 22) == 0 ||
2344 strncmp (signal_spec, "swapped-signal-after::", 22) == 0)
2345 g_signal_connect_data (object, signal_spec + 22,
2346 callback, data, NULL,
2347 G_CONNECT_SWAPPED | G_CONNECT_AFTER);
2348 else if (strncmp (signal_spec, "swapped_object_signal_after::", 29) == 0 ||
2349 strncmp (signal_spec, "swapped-object-signal-after::", 29) == 0)
2350 g_signal_connect_object (object, signal_spec + 29,
2352 G_CONNECT_SWAPPED | G_CONNECT_AFTER);
2355 g_warning ("%s: invalid signal spec \"%s\"", G_STRFUNC, signal_spec);
2358 signal_spec = va_arg (var_args, gchar*);
2366 * g_object_disconnect: (skip)
2367 * @object: a #GObject
2368 * @signal_spec: the spec for the first signal
2369 * @...: #GCallback for the first signal, followed by data for the first signal,
2370 * followed optionally by more signal spec/callback/data triples,
2373 * A convenience function to disconnect multiple signals at once.
2375 * The signal specs expected by this function have the form
2376 * "any_signal", which means to disconnect any signal with matching
2377 * callback and data, or "any_signal::signal_name", which only
2378 * disconnects the signal named "signal_name".
2381 g_object_disconnect (gpointer _object,
2382 const gchar *signal_spec,
2385 GObject *object = _object;
2388 g_return_if_fail (G_IS_OBJECT (object));
2389 g_return_if_fail (object->ref_count > 0);
2391 va_start (var_args, signal_spec);
2394 GCallback callback = va_arg (var_args, GCallback);
2395 gpointer data = va_arg (var_args, gpointer);
2396 guint sid = 0, detail = 0, mask = 0;
2398 if (strncmp (signal_spec, "any_signal::", 12) == 0 ||
2399 strncmp (signal_spec, "any-signal::", 12) == 0)
2402 mask = G_SIGNAL_MATCH_ID | G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA;
2404 else if (strcmp (signal_spec, "any_signal") == 0 ||
2405 strcmp (signal_spec, "any-signal") == 0)
2408 mask = G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA;
2412 g_warning ("%s: invalid signal spec \"%s\"", G_STRFUNC, signal_spec);
2416 if ((mask & G_SIGNAL_MATCH_ID) &&
2417 !g_signal_parse_name (signal_spec, G_OBJECT_TYPE (object), &sid, &detail, FALSE))
2418 g_warning ("%s: invalid signal name \"%s\"", G_STRFUNC, signal_spec);
2419 else if (!g_signal_handlers_disconnect_matched (object, mask | (detail ? G_SIGNAL_MATCH_DETAIL : 0),
2421 NULL, (gpointer)callback, data))
2422 g_warning ("%s: signal handler %p(%p) is not connected", G_STRFUNC, callback, data);
2423 signal_spec = va_arg (var_args, gchar*);
2434 } weak_refs[1]; /* flexible array */
2438 weak_refs_notify (gpointer data)
2440 WeakRefStack *wstack = data;
2443 for (i = 0; i < wstack->n_weak_refs; i++)
2444 wstack->weak_refs[i].notify (wstack->weak_refs[i].data, wstack->object);
2449 * g_object_weak_ref: (skip)
2450 * @object: #GObject to reference weakly
2451 * @notify: callback to invoke before the object is freed
2452 * @data: extra data to pass to notify
2454 * Adds a weak reference callback to an object. Weak references are
2455 * used for notification when an object is finalized. They are called
2456 * "weak references" because they allow you to safely hold a pointer
2457 * to an object without calling g_object_ref() (g_object_ref() adds a
2458 * strong reference, that is, forces the object to stay alive).
2461 g_object_weak_ref (GObject *object,
2465 WeakRefStack *wstack;
2468 g_return_if_fail (G_IS_OBJECT (object));
2469 g_return_if_fail (notify != NULL);
2470 g_return_if_fail (object->ref_count >= 1);
2472 G_LOCK (weak_refs_mutex);
2473 wstack = g_datalist_id_remove_no_notify (&object->qdata, quark_weak_refs);
2476 i = wstack->n_weak_refs++;
2477 wstack = g_realloc (wstack, sizeof (*wstack) + sizeof (wstack->weak_refs[0]) * i);
2481 wstack = g_renew (WeakRefStack, NULL, 1);
2482 wstack->object = object;
2483 wstack->n_weak_refs = 1;
2486 wstack->weak_refs[i].notify = notify;
2487 wstack->weak_refs[i].data = data;
2488 g_datalist_id_set_data_full (&object->qdata, quark_weak_refs, wstack, weak_refs_notify);
2489 G_UNLOCK (weak_refs_mutex);
2493 * g_object_weak_unref: (skip)
2494 * @object: #GObject to remove a weak reference from
2495 * @notify: callback to search for
2496 * @data: data to search for
2498 * Removes a weak reference callback to an object.
2501 g_object_weak_unref (GObject *object,
2505 WeakRefStack *wstack;
2506 gboolean found_one = FALSE;
2508 g_return_if_fail (G_IS_OBJECT (object));
2509 g_return_if_fail (notify != NULL);
2511 G_LOCK (weak_refs_mutex);
2512 wstack = g_datalist_id_get_data (&object->qdata, quark_weak_refs);
2517 for (i = 0; i < wstack->n_weak_refs; i++)
2518 if (wstack->weak_refs[i].notify == notify &&
2519 wstack->weak_refs[i].data == data)
2522 wstack->n_weak_refs -= 1;
2523 if (i != wstack->n_weak_refs)
2524 wstack->weak_refs[i] = wstack->weak_refs[wstack->n_weak_refs];
2529 G_UNLOCK (weak_refs_mutex);
2531 g_warning ("%s: couldn't find weak ref %p(%p)", G_STRFUNC, notify, data);
2535 * g_object_add_weak_pointer: (skip)
2536 * @object: The object that should be weak referenced.
2537 * @weak_pointer_location: (inout): The memory address of a pointer.
2539 * Adds a weak reference from weak_pointer to @object to indicate that
2540 * the pointer located at @weak_pointer_location is only valid during
2541 * the lifetime of @object. When the @object is finalized,
2542 * @weak_pointer will be set to %NULL.
2545 g_object_add_weak_pointer (GObject *object,
2546 gpointer *weak_pointer_location)
2548 g_return_if_fail (G_IS_OBJECT (object));
2549 g_return_if_fail (weak_pointer_location != NULL);
2551 g_object_weak_ref (object,
2552 (GWeakNotify) g_nullify_pointer,
2553 weak_pointer_location);
2557 * g_object_remove_weak_pointer: (skip)
2558 * @object: The object that is weak referenced.
2559 * @weak_pointer_location: (inout): The memory address of a pointer.
2561 * Removes a weak reference from @object that was previously added
2562 * using g_object_add_weak_pointer(). The @weak_pointer_location has
2563 * to match the one used with g_object_add_weak_pointer().
2566 g_object_remove_weak_pointer (GObject *object,
2567 gpointer *weak_pointer_location)
2569 g_return_if_fail (G_IS_OBJECT (object));
2570 g_return_if_fail (weak_pointer_location != NULL);
2572 g_object_weak_unref (object,
2573 (GWeakNotify) g_nullify_pointer,
2574 weak_pointer_location);
2578 object_floating_flag_handler (GObject *object,
2584 case +1: /* force floating if possible */
2586 oldvalue = g_atomic_pointer_get (&object->qdata);
2587 while (!g_atomic_pointer_compare_and_exchange ((void**) &object->qdata, oldvalue,
2588 (gpointer) ((gsize) oldvalue | OBJECT_FLOATING_FLAG)));
2589 return (gsize) oldvalue & OBJECT_FLOATING_FLAG;
2590 case -1: /* sink if possible */
2592 oldvalue = g_atomic_pointer_get (&object->qdata);
2593 while (!g_atomic_pointer_compare_and_exchange ((void**) &object->qdata, oldvalue,
2594 (gpointer) ((gsize) oldvalue & ~(gsize) OBJECT_FLOATING_FLAG)));
2595 return (gsize) oldvalue & OBJECT_FLOATING_FLAG;
2596 default: /* check floating */
2597 return 0 != ((gsize) g_atomic_pointer_get (&object->qdata) & OBJECT_FLOATING_FLAG);
2602 * g_object_is_floating:
2603 * @object: (type GObject.Object): a #GObject
2605 * Checks whether @object has a <link linkend="floating-ref">floating</link>
2610 * Returns: %TRUE if @object has a floating reference
2613 g_object_is_floating (gpointer _object)
2615 GObject *object = _object;
2616 g_return_val_if_fail (G_IS_OBJECT (object), FALSE);
2617 return floating_flag_handler (object, 0);
2621 * g_object_ref_sink:
2622 * @object: (type GObject.Object): a #GObject
2624 * Increase the reference count of @object, and possibly remove the
2625 * <link linkend="floating-ref">floating</link> reference, if @object
2626 * has a floating reference.
2628 * In other words, if the object is floating, then this call "assumes
2629 * ownership" of the floating reference, converting it to a normal
2630 * reference by clearing the floating flag while leaving the reference
2631 * count unchanged. If the object is not floating, then this call
2632 * adds a new normal reference increasing the reference count by one.
2636 * Returns: (type GObject.Object) (transfer none): @object
2639 g_object_ref_sink (gpointer _object)
2641 GObject *object = _object;
2642 gboolean was_floating;
2643 g_return_val_if_fail (G_IS_OBJECT (object), object);
2644 g_return_val_if_fail (object->ref_count >= 1, object);
2645 g_object_ref (object);
2646 was_floating = floating_flag_handler (object, -1);
2648 g_object_unref (object);
2653 * g_object_force_floating:
2654 * @object: a #GObject
2656 * This function is intended for #GObject implementations to re-enforce a
2657 * <link linkend="floating-ref">floating</link> object reference.
2658 * Doing this is seldom required: all
2659 * #GInitiallyUnowned<!-- -->s are created with a floating reference which
2660 * usually just needs to be sunken by calling g_object_ref_sink().
2665 g_object_force_floating (GObject *object)
2667 g_return_if_fail (G_IS_OBJECT (object));
2668 g_return_if_fail (object->ref_count >= 1);
2670 floating_flag_handler (object, +1);
2675 guint n_toggle_refs;
2677 GToggleNotify notify;
2679 } toggle_refs[1]; /* flexible array */
2683 toggle_refs_notify (GObject *object,
2684 gboolean is_last_ref)
2686 ToggleRefStack tstack, *tstackptr;
2688 G_LOCK (toggle_refs_mutex);
2689 tstackptr = g_datalist_id_get_data (&object->qdata, quark_toggle_refs);
2690 tstack = *tstackptr;
2691 G_UNLOCK (toggle_refs_mutex);
2693 /* Reentrancy here is not as tricky as it seems, because a toggle reference
2694 * will only be notified when there is exactly one of them.
2696 g_assert (tstack.n_toggle_refs == 1);
2697 tstack.toggle_refs[0].notify (tstack.toggle_refs[0].data, tstack.object, is_last_ref);
2701 * g_object_add_toggle_ref: (skip)
2702 * @object: a #GObject
2703 * @notify: a function to call when this reference is the
2704 * last reference to the object, or is no longer
2705 * the last reference.
2706 * @data: data to pass to @notify
2708 * Increases the reference count of the object by one and sets a
2709 * callback to be called when all other references to the object are
2710 * dropped, or when this is already the last reference to the object
2711 * and another reference is established.
2713 * This functionality is intended for binding @object to a proxy
2714 * object managed by another memory manager. This is done with two
2715 * paired references: the strong reference added by
2716 * g_object_add_toggle_ref() and a reverse reference to the proxy
2717 * object which is either a strong reference or weak reference.
2719 * The setup is that when there are no other references to @object,
2720 * only a weak reference is held in the reverse direction from @object
2721 * to the proxy object, but when there are other references held to
2722 * @object, a strong reference is held. The @notify callback is called
2723 * when the reference from @object to the proxy object should be
2724 * <firstterm>toggled</firstterm> from strong to weak (@is_last_ref
2725 * true) or weak to strong (@is_last_ref false).
2727 * Since a (normal) reference must be held to the object before
2728 * calling g_object_add_toggle_ref(), the initial state of the reverse
2729 * link is always strong.
2731 * Multiple toggle references may be added to the same gobject,
2732 * however if there are multiple toggle references to an object, none
2733 * of them will ever be notified until all but one are removed. For
2734 * this reason, you should only ever use a toggle reference if there
2735 * is important state in the proxy object.
2740 g_object_add_toggle_ref (GObject *object,
2741 GToggleNotify notify,
2744 ToggleRefStack *tstack;
2747 g_return_if_fail (G_IS_OBJECT (object));
2748 g_return_if_fail (notify != NULL);
2749 g_return_if_fail (object->ref_count >= 1);
2751 g_object_ref (object);
2753 G_LOCK (toggle_refs_mutex);
2754 tstack = g_datalist_id_remove_no_notify (&object->qdata, quark_toggle_refs);
2757 i = tstack->n_toggle_refs++;
2758 /* allocate i = tstate->n_toggle_refs - 1 positions beyond the 1 declared
2759 * in tstate->toggle_refs */
2760 tstack = g_realloc (tstack, sizeof (*tstack) + sizeof (tstack->toggle_refs[0]) * i);
2764 tstack = g_renew (ToggleRefStack, NULL, 1);
2765 tstack->object = object;
2766 tstack->n_toggle_refs = 1;
2770 /* Set a flag for fast lookup after adding the first toggle reference */
2771 if (tstack->n_toggle_refs == 1)
2772 g_datalist_set_flags (&object->qdata, OBJECT_HAS_TOGGLE_REF_FLAG);
2774 tstack->toggle_refs[i].notify = notify;
2775 tstack->toggle_refs[i].data = data;
2776 g_datalist_id_set_data_full (&object->qdata, quark_toggle_refs, tstack,
2777 (GDestroyNotify)g_free);
2778 G_UNLOCK (toggle_refs_mutex);
2782 * g_object_remove_toggle_ref: (skip)
2783 * @object: a #GObject
2784 * @notify: a function to call when this reference is the
2785 * last reference to the object, or is no longer
2786 * the last reference.
2787 * @data: data to pass to @notify
2789 * Removes a reference added with g_object_add_toggle_ref(). The
2790 * reference count of the object is decreased by one.
2795 g_object_remove_toggle_ref (GObject *object,
2796 GToggleNotify notify,
2799 ToggleRefStack *tstack;
2800 gboolean found_one = FALSE;
2802 g_return_if_fail (G_IS_OBJECT (object));
2803 g_return_if_fail (notify != NULL);
2805 G_LOCK (toggle_refs_mutex);
2806 tstack = g_datalist_id_get_data (&object->qdata, quark_toggle_refs);
2811 for (i = 0; i < tstack->n_toggle_refs; i++)
2812 if (tstack->toggle_refs[i].notify == notify &&
2813 tstack->toggle_refs[i].data == data)
2816 tstack->n_toggle_refs -= 1;
2817 if (i != tstack->n_toggle_refs)
2818 tstack->toggle_refs[i] = tstack->toggle_refs[tstack->n_toggle_refs];
2820 if (tstack->n_toggle_refs == 0)
2821 g_datalist_unset_flags (&object->qdata, OBJECT_HAS_TOGGLE_REF_FLAG);
2826 G_UNLOCK (toggle_refs_mutex);
2829 g_object_unref (object);
2831 g_warning ("%s: couldn't find toggle ref %p(%p)", G_STRFUNC, notify, data);
2836 * @object: (type GObject.Object): a #GObject
2838 * Increases the reference count of @object.
2840 * Returns: (type GObject.Object) (transfer none): the same @object
2843 g_object_ref (gpointer _object)
2845 GObject *object = _object;
2848 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
2849 g_return_val_if_fail (object->ref_count > 0, NULL);
2851 #ifdef G_ENABLE_DEBUG
2852 if (g_trap_object_ref == object)
2854 #endif /* G_ENABLE_DEBUG */
2857 old_val = g_atomic_int_add (&object->ref_count, 1);
2859 if (old_val == 1 && OBJECT_HAS_TOGGLE_REF (object))
2860 toggle_refs_notify (object, FALSE);
2862 TRACE (GOBJECT_OBJECT_REF(object,G_TYPE_FROM_INSTANCE(object),old_val));
2869 * @object: (type GObject.Object): a #GObject
2871 * Decreases the reference count of @object. When its reference count
2872 * drops to 0, the object is finalized (i.e. its memory is freed).
2875 g_object_unref (gpointer _object)
2877 GObject *object = _object;
2880 g_return_if_fail (G_IS_OBJECT (object));
2881 g_return_if_fail (object->ref_count > 0);
2883 #ifdef G_ENABLE_DEBUG
2884 if (g_trap_object_ref == object)
2886 #endif /* G_ENABLE_DEBUG */
2888 /* here we want to atomically do: if (ref_count>1) { ref_count--; return; } */
2889 retry_atomic_decrement1:
2890 old_ref = g_atomic_int_get (&object->ref_count);
2893 /* valid if last 2 refs are owned by this call to unref and the toggle_ref */
2894 gboolean has_toggle_ref = OBJECT_HAS_TOGGLE_REF (object);
2896 if (!g_atomic_int_compare_and_exchange ((int *)&object->ref_count, old_ref, old_ref - 1))
2897 goto retry_atomic_decrement1;
2899 TRACE (GOBJECT_OBJECT_UNREF(object,G_TYPE_FROM_INSTANCE(object),old_ref));
2901 /* if we went from 2->1 we need to notify toggle refs if any */
2902 if (old_ref == 2 && has_toggle_ref) /* The last ref being held in this case is owned by the toggle_ref */
2903 toggle_refs_notify (object, TRUE);
2907 /* we are about tp remove the last reference */
2908 TRACE (GOBJECT_OBJECT_DISPOSE(object,G_TYPE_FROM_INSTANCE(object), 1));
2909 G_OBJECT_GET_CLASS (object)->dispose (object);
2910 TRACE (GOBJECT_OBJECT_DISPOSE_END(object,G_TYPE_FROM_INSTANCE(object), 1));
2912 /* may have been re-referenced meanwhile */
2913 retry_atomic_decrement2:
2914 old_ref = g_atomic_int_get ((int *)&object->ref_count);
2917 /* valid if last 2 refs are owned by this call to unref and the toggle_ref */
2918 gboolean has_toggle_ref = OBJECT_HAS_TOGGLE_REF (object);
2920 if (!g_atomic_int_compare_and_exchange ((int *)&object->ref_count, old_ref, old_ref - 1))
2921 goto retry_atomic_decrement2;
2923 TRACE (GOBJECT_OBJECT_UNREF(object,G_TYPE_FROM_INSTANCE(object),old_ref));
2925 /* if we went from 2->1 we need to notify toggle refs if any */
2926 if (old_ref == 2 && has_toggle_ref) /* The last ref being held in this case is owned by the toggle_ref */
2927 toggle_refs_notify (object, TRUE);
2932 /* we are still in the process of taking away the last ref */
2933 g_datalist_id_set_data (&object->qdata, quark_closure_array, NULL);
2934 g_signal_handlers_destroy (object);
2935 g_datalist_id_set_data (&object->qdata, quark_weak_refs, NULL);
2937 /* decrement the last reference */
2938 old_ref = g_atomic_int_add (&object->ref_count, -1);
2940 TRACE (GOBJECT_OBJECT_UNREF(object,G_TYPE_FROM_INSTANCE(object),old_ref));
2942 /* may have been re-referenced meanwhile */
2943 if (G_LIKELY (old_ref == 1))
2945 TRACE (GOBJECT_OBJECT_FINALIZE(object,G_TYPE_FROM_INSTANCE(object)));
2946 G_OBJECT_GET_CLASS (object)->finalize (object);
2948 TRACE (GOBJECT_OBJECT_FINALIZE_END(object,G_TYPE_FROM_INSTANCE(object)));
2950 #ifdef G_ENABLE_DEBUG
2953 /* catch objects not chaining finalize handlers */
2954 G_LOCK (debug_objects);
2955 g_assert (g_hash_table_lookup (debug_objects_ht, object) == NULL);
2956 G_UNLOCK (debug_objects);
2958 #endif /* G_ENABLE_DEBUG */
2959 g_type_free_instance ((GTypeInstance*) object);
2965 * g_clear_object: (skip)
2966 * @object_ptr: a pointer to a #GObject reference
2968 * Clears a reference to a #GObject.
2970 * @object_ptr must not be %NULL.
2972 * If the reference is %NULL then this function does nothing.
2973 * Otherwise, the reference count of the object is decreased and the
2974 * pointer is set to %NULL.
2976 * This function is threadsafe and modifies the pointer atomically,
2977 * using memory barriers where needed.
2979 * A macro is also included that allows this function to be used without
2984 #undef g_clear_object
2986 g_clear_object (volatile GObject **object_ptr)
2988 gpointer *ptr = (gpointer) object_ptr;
2991 /* This is a little frustrating.
2992 * Would be nice to have an atomic exchange (with no compare).
2995 old = g_atomic_pointer_get (ptr);
2996 while G_UNLIKELY (!g_atomic_pointer_compare_and_exchange (ptr, old, NULL));
2999 g_object_unref (old);
3003 * g_object_get_qdata:
3004 * @object: The GObject to get a stored user data pointer from
3005 * @quark: A #GQuark, naming the user data pointer
3007 * This function gets back user data pointers stored via
3008 * g_object_set_qdata().
3010 * Returns: (transfer none): The user data pointer set, or %NULL
3013 g_object_get_qdata (GObject *object,
3016 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
3018 return quark ? g_datalist_id_get_data (&object->qdata, quark) : NULL;
3022 * g_object_set_qdata: (skip)
3023 * @object: The GObject to set store a user data pointer
3024 * @quark: A #GQuark, naming the user data pointer
3025 * @data: An opaque user data pointer
3027 * This sets an opaque, named pointer on an object.
3028 * The name is specified through a #GQuark (retrived e.g. via
3029 * g_quark_from_static_string()), and the pointer
3030 * can be gotten back from the @object with g_object_get_qdata()
3031 * until the @object is finalized.
3032 * Setting a previously set user data pointer, overrides (frees)
3033 * the old pointer set, using #NULL as pointer essentially
3034 * removes the data stored.
3037 g_object_set_qdata (GObject *object,
3041 g_return_if_fail (G_IS_OBJECT (object));
3042 g_return_if_fail (quark > 0);
3044 g_datalist_id_set_data (&object->qdata, quark, data);
3048 * g_object_set_qdata_full: (skip)
3049 * @object: The GObject to set store a user data pointer
3050 * @quark: A #GQuark, naming the user data pointer
3051 * @data: An opaque user data pointer
3052 * @destroy: Function to invoke with @data as argument, when @data
3055 * This function works like g_object_set_qdata(), but in addition,
3056 * a void (*destroy) (gpointer) function may be specified which is
3057 * called with @data as argument when the @object is finalized, or
3058 * the data is being overwritten by a call to g_object_set_qdata()
3059 * with the same @quark.
3062 g_object_set_qdata_full (GObject *object,
3065 GDestroyNotify destroy)
3067 g_return_if_fail (G_IS_OBJECT (object));
3068 g_return_if_fail (quark > 0);
3070 g_datalist_id_set_data_full (&object->qdata, quark, data,
3071 data ? destroy : (GDestroyNotify) NULL);
3075 * g_object_steal_qdata:
3076 * @object: The GObject to get a stored user data pointer from
3077 * @quark: A #GQuark, naming the user data pointer
3079 * This function gets back user data pointers stored via
3080 * g_object_set_qdata() and removes the @data from object
3081 * without invoking its destroy() function (if any was
3083 * Usually, calling this function is only required to update
3084 * user data pointers with a destroy notifier, for example:
3087 * object_add_to_user_list (GObject *object,
3088 * const gchar *new_string)
3090 * // the quark, naming the object data
3091 * GQuark quark_string_list = g_quark_from_static_string ("my-string-list");
3092 * // retrive the old string list
3093 * GList *list = g_object_steal_qdata (object, quark_string_list);
3095 * // prepend new string
3096 * list = g_list_prepend (list, g_strdup (new_string));
3097 * // this changed 'list', so we need to set it again
3098 * g_object_set_qdata_full (object, quark_string_list, list, free_string_list);
3101 * free_string_list (gpointer data)
3103 * GList *node, *list = data;
3105 * for (node = list; node; node = node->next)
3106 * g_free (node->data);
3107 * g_list_free (list);
3110 * Using g_object_get_qdata() in the above example, instead of
3111 * g_object_steal_qdata() would have left the destroy function set,
3112 * and thus the partial string list would have been freed upon
3113 * g_object_set_qdata_full().
3115 * Returns: (transfer full): The user data pointer set, or %NULL
3118 g_object_steal_qdata (GObject *object,
3121 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
3122 g_return_val_if_fail (quark > 0, NULL);
3124 return g_datalist_id_remove_no_notify (&object->qdata, quark);
3128 * g_object_get_data:
3129 * @object: #GObject containing the associations
3130 * @key: name of the key for that association
3132 * Gets a named field from the objects table of associations (see g_object_set_data()).
3134 * Returns: (transfer none): the data if found, or %NULL if no such data exists.
3137 g_object_get_data (GObject *object,
3140 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
3141 g_return_val_if_fail (key != NULL, NULL);
3143 return g_datalist_get_data (&object->qdata, key);
3147 * g_object_set_data:
3148 * @object: #GObject containing the associations.
3149 * @key: name of the key
3150 * @data: data to associate with that key
3152 * Each object carries around a table of associations from
3153 * strings to pointers. This function lets you set an association.
3155 * If the object already had an association with that name,
3156 * the old association will be destroyed.
3159 g_object_set_data (GObject *object,
3163 g_return_if_fail (G_IS_OBJECT (object));
3164 g_return_if_fail (key != NULL);
3166 g_datalist_id_set_data (&object->qdata, g_quark_from_string (key), data);
3170 * g_object_set_data_full: (skip)
3171 * @object: #GObject containing the associations
3172 * @key: name of the key
3173 * @data: data to associate with that key
3174 * @destroy: function to call when the association is destroyed
3176 * Like g_object_set_data() except it adds notification
3177 * for when the association is destroyed, either by setting it
3178 * to a different value or when the object is destroyed.
3180 * Note that the @destroy callback is not called if @data is %NULL.
3183 g_object_set_data_full (GObject *object,
3186 GDestroyNotify destroy)
3188 g_return_if_fail (G_IS_OBJECT (object));
3189 g_return_if_fail (key != NULL);
3191 g_datalist_id_set_data_full (&object->qdata, g_quark_from_string (key), data,
3192 data ? destroy : (GDestroyNotify) NULL);
3196 * g_object_steal_data:
3197 * @object: #GObject containing the associations
3198 * @key: name of the key
3200 * Remove a specified datum from the object's data associations,
3201 * without invoking the association's destroy handler.
3203 * Returns: (transfer full): the data if found, or %NULL if no such data exists.
3206 g_object_steal_data (GObject *object,
3211 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
3212 g_return_val_if_fail (key != NULL, NULL);
3214 quark = g_quark_try_string (key);
3216 return quark ? g_datalist_id_remove_no_notify (&object->qdata, quark) : NULL;
3220 g_value_object_init (GValue *value)
3222 value->data[0].v_pointer = NULL;
3226 g_value_object_free_value (GValue *value)
3228 if (value->data[0].v_pointer)
3229 g_object_unref (value->data[0].v_pointer);
3233 g_value_object_copy_value (const GValue *src_value,
3236 if (src_value->data[0].v_pointer)
3237 dest_value->data[0].v_pointer = g_object_ref (src_value->data[0].v_pointer);
3239 dest_value->data[0].v_pointer = NULL;
3243 g_value_object_transform_value (const GValue *src_value,
3246 if (src_value->data[0].v_pointer && g_type_is_a (G_OBJECT_TYPE (src_value->data[0].v_pointer), G_VALUE_TYPE (dest_value)))
3247 dest_value->data[0].v_pointer = g_object_ref (src_value->data[0].v_pointer);
3249 dest_value->data[0].v_pointer = NULL;
3253 g_value_object_peek_pointer (const GValue *value)
3255 return value->data[0].v_pointer;
3259 g_value_object_collect_value (GValue *value,
3260 guint n_collect_values,
3261 GTypeCValue *collect_values,
3262 guint collect_flags)
3264 if (collect_values[0].v_pointer)
3266 GObject *object = collect_values[0].v_pointer;
3268 if (object->g_type_instance.g_class == NULL)
3269 return g_strconcat ("invalid unclassed object pointer for value type `",
3270 G_VALUE_TYPE_NAME (value),
3273 else if (!g_value_type_compatible (G_OBJECT_TYPE (object), G_VALUE_TYPE (value)))
3274 return g_strconcat ("invalid object type `",
3275 G_OBJECT_TYPE_NAME (object),
3276 "' for value type `",
3277 G_VALUE_TYPE_NAME (value),
3280 /* never honour G_VALUE_NOCOPY_CONTENTS for ref-counted types */
3281 value->data[0].v_pointer = g_object_ref (object);
3284 value->data[0].v_pointer = NULL;
3290 g_value_object_lcopy_value (const GValue *value,
3291 guint n_collect_values,
3292 GTypeCValue *collect_values,
3293 guint collect_flags)
3295 GObject **object_p = collect_values[0].v_pointer;
3298 return g_strdup_printf ("value location for `%s' passed as NULL", G_VALUE_TYPE_NAME (value));
3300 if (!value->data[0].v_pointer)
3302 else if (collect_flags & G_VALUE_NOCOPY_CONTENTS)
3303 *object_p = value->data[0].v_pointer;
3305 *object_p = g_object_ref (value->data[0].v_pointer);
3311 * g_value_set_object:
3312 * @value: a valid #GValue of %G_TYPE_OBJECT derived type
3313 * @v_object: (type GObject.Object) (allow-none): object value to be set
3315 * Set the contents of a %G_TYPE_OBJECT derived #GValue to @v_object.
3317 * g_value_set_object() increases the reference count of @v_object
3318 * (the #GValue holds a reference to @v_object). If you do not wish
3319 * to increase the reference count of the object (i.e. you wish to
3320 * pass your current reference to the #GValue because you no longer
3321 * need it), use g_value_take_object() instead.
3323 * It is important that your #GValue holds a reference to @v_object (either its
3324 * own, or one it has taken) to ensure that the object won't be destroyed while
3325 * the #GValue still exists).
3328 g_value_set_object (GValue *value,
3333 g_return_if_fail (G_VALUE_HOLDS_OBJECT (value));
3335 old = value->data[0].v_pointer;
3339 g_return_if_fail (G_IS_OBJECT (v_object));
3340 g_return_if_fail (g_value_type_compatible (G_OBJECT_TYPE (v_object), G_VALUE_TYPE (value)));
3342 value->data[0].v_pointer = v_object;
3343 g_object_ref (value->data[0].v_pointer);
3346 value->data[0].v_pointer = NULL;
3349 g_object_unref (old);
3353 * g_value_set_object_take_ownership: (skip)
3354 * @value: a valid #GValue of %G_TYPE_OBJECT derived type
3355 * @v_object: (allow-none): object value to be set
3357 * This is an internal function introduced mainly for C marshallers.
3359 * Deprecated: 2.4: Use g_value_take_object() instead.
3362 g_value_set_object_take_ownership (GValue *value,
3365 g_value_take_object (value, v_object);
3369 * g_value_take_object: (skip)
3370 * @value: a valid #GValue of %G_TYPE_OBJECT derived type
3371 * @v_object: (allow-none): object value to be set
3373 * Sets the contents of a %G_TYPE_OBJECT derived #GValue to @v_object
3374 * and takes over the ownership of the callers reference to @v_object;
3375 * the caller doesn't have to unref it any more (i.e. the reference
3376 * count of the object is not increased).
3378 * If you want the #GValue to hold its own reference to @v_object, use
3379 * g_value_set_object() instead.
3384 g_value_take_object (GValue *value,
3387 g_return_if_fail (G_VALUE_HOLDS_OBJECT (value));
3389 if (value->data[0].v_pointer)
3391 g_object_unref (value->data[0].v_pointer);
3392 value->data[0].v_pointer = NULL;
3397 g_return_if_fail (G_IS_OBJECT (v_object));
3398 g_return_if_fail (g_value_type_compatible (G_OBJECT_TYPE (v_object), G_VALUE_TYPE (value)));
3400 value->data[0].v_pointer = v_object; /* we take over the reference count */
3405 * g_value_get_object:
3406 * @value: a valid #GValue of %G_TYPE_OBJECT derived type
3408 * Get the contents of a %G_TYPE_OBJECT derived #GValue.
3410 * Returns: (type GObject.Object) (transfer none): object contents of @value
3413 g_value_get_object (const GValue *value)
3415 g_return_val_if_fail (G_VALUE_HOLDS_OBJECT (value), NULL);
3417 return value->data[0].v_pointer;
3421 * g_value_dup_object:
3422 * @value: a valid #GValue whose type is derived from %G_TYPE_OBJECT
3424 * Get the contents of a %G_TYPE_OBJECT derived #GValue, increasing
3425 * its reference count. If the contents of the #GValue are %NULL, then
3426 * %NULL will be returned.
3428 * Returns: (type GObject.Object) (transfer full): object content of @value,
3429 * should be unreferenced when no longer needed.
3432 g_value_dup_object (const GValue *value)
3434 g_return_val_if_fail (G_VALUE_HOLDS_OBJECT (value), NULL);
3436 return value->data[0].v_pointer ? g_object_ref (value->data[0].v_pointer) : NULL;
3440 * g_signal_connect_object: (skip)
3441 * @instance: the instance to connect to.
3442 * @detailed_signal: a string of the form "signal-name::detail".
3443 * @c_handler: the #GCallback to connect.
3444 * @gobject: the object to pass as data to @c_handler.
3445 * @connect_flags: a combination of #GConnectFlags.
3447 * This is similar to g_signal_connect_data(), but uses a closure which
3448 * ensures that the @gobject stays alive during the call to @c_handler
3449 * by temporarily adding a reference count to @gobject.
3451 * Note that there is a bug in GObject that makes this function
3452 * much less useful than it might seem otherwise. Once @gobject is
3453 * disposed, the callback will no longer be called, but, the signal
3454 * handler is <emphasis>not</emphasis> currently disconnected. If the
3455 * @instance is itself being freed at the same time than this doesn't
3456 * matter, since the signal will automatically be removed, but
3457 * if @instance persists, then the signal handler will leak. You
3458 * should not remove the signal yourself because in a future versions of
3459 * GObject, the handler <emphasis>will</emphasis> automatically
3462 * It's possible to work around this problem in a way that will
3463 * continue to work with future versions of GObject by checking
3464 * that the signal handler is still connected before disconnected it:
3465 * <informalexample><programlisting>
3466 * if (g_signal_handler_is_connected (instance, id))
3467 * g_signal_handler_disconnect (instance, id);
3468 * </programlisting></informalexample>
3470 * Returns: the handler id.
3473 g_signal_connect_object (gpointer instance,
3474 const gchar *detailed_signal,
3475 GCallback c_handler,
3477 GConnectFlags connect_flags)
3479 g_return_val_if_fail (G_TYPE_CHECK_INSTANCE (instance), 0);
3480 g_return_val_if_fail (detailed_signal != NULL, 0);
3481 g_return_val_if_fail (c_handler != NULL, 0);
3487 g_return_val_if_fail (G_IS_OBJECT (gobject), 0);
3489 closure = ((connect_flags & G_CONNECT_SWAPPED) ? g_cclosure_new_object_swap : g_cclosure_new_object) (c_handler, gobject);
3491 return g_signal_connect_closure (instance, detailed_signal, closure, connect_flags & G_CONNECT_AFTER);
3494 return g_signal_connect_data (instance, detailed_signal, c_handler, NULL, NULL, connect_flags);
3500 GClosure *closures[1]; /* flexible array */
3502 /* don't change this structure without supplying an accessor for
3503 * watched closures, e.g.:
3504 * GSList* g_object_list_watched_closures (GObject *object)
3507 * g_return_val_if_fail (G_IS_OBJECT (object), NULL);
3508 * carray = g_object_get_data (object, "GObject-closure-array");
3511 * GSList *slist = NULL;
3513 * for (i = 0; i < carray->n_closures; i++)
3514 * slist = g_slist_prepend (slist, carray->closures[i]);
3522 object_remove_closure (gpointer data,
3525 GObject *object = data;
3529 G_LOCK (closure_array_mutex);
3530 carray = g_object_get_qdata (object, quark_closure_array);
3531 for (i = 0; i < carray->n_closures; i++)
3532 if (carray->closures[i] == closure)
3534 carray->n_closures--;
3535 if (i < carray->n_closures)
3536 carray->closures[i] = carray->closures[carray->n_closures];
3537 G_UNLOCK (closure_array_mutex);
3540 G_UNLOCK (closure_array_mutex);
3541 g_assert_not_reached ();
3545 destroy_closure_array (gpointer data)
3547 CArray *carray = data;
3548 GObject *object = carray->object;
3549 guint i, n = carray->n_closures;
3551 for (i = 0; i < n; i++)
3553 GClosure *closure = carray->closures[i];
3555 /* removing object_remove_closure() upfront is probably faster than
3556 * letting it fiddle with quark_closure_array which is empty anyways
3558 g_closure_remove_invalidate_notifier (closure, object, object_remove_closure);
3559 g_closure_invalidate (closure);
3565 * g_object_watch_closure:
3566 * @object: GObject restricting lifetime of @closure
3567 * @closure: GClosure to watch
3569 * This function essentially limits the life time of the @closure to
3570 * the life time of the object. That is, when the object is finalized,
3571 * the @closure is invalidated by calling g_closure_invalidate() on
3572 * it, in order to prevent invocations of the closure with a finalized
3573 * (nonexisting) object. Also, g_object_ref() and g_object_unref() are
3574 * added as marshal guards to the @closure, to ensure that an extra
3575 * reference count is held on @object during invocation of the
3576 * @closure. Usually, this function will be called on closures that
3577 * use this @object as closure data.
3580 g_object_watch_closure (GObject *object,
3586 g_return_if_fail (G_IS_OBJECT (object));
3587 g_return_if_fail (closure != NULL);
3588 g_return_if_fail (closure->is_invalid == FALSE);
3589 g_return_if_fail (closure->in_marshal == FALSE);
3590 g_return_if_fail (object->ref_count > 0); /* this doesn't work on finalizing objects */
3592 g_closure_add_invalidate_notifier (closure, object, object_remove_closure);
3593 g_closure_add_marshal_guards (closure,
3594 object, (GClosureNotify) g_object_ref,
3595 object, (GClosureNotify) g_object_unref);
3596 G_LOCK (closure_array_mutex);
3597 carray = g_datalist_id_remove_no_notify (&object->qdata, quark_closure_array);
3600 carray = g_renew (CArray, NULL, 1);
3601 carray->object = object;
3602 carray->n_closures = 1;
3607 i = carray->n_closures++;
3608 carray = g_realloc (carray, sizeof (*carray) + sizeof (carray->closures[0]) * i);
3610 carray->closures[i] = closure;
3611 g_datalist_id_set_data_full (&object->qdata, quark_closure_array, carray, destroy_closure_array);
3612 G_UNLOCK (closure_array_mutex);
3616 * g_closure_new_object:
3617 * @sizeof_closure: the size of the structure to allocate, must be at least
3618 * <literal>sizeof (GClosure)</literal>
3619 * @object: a #GObject pointer to store in the @data field of the newly
3620 * allocated #GClosure
3622 * A variant of g_closure_new_simple() which stores @object in the
3623 * @data field of the closure and calls g_object_watch_closure() on
3624 * @object and the created closure. This function is mainly useful
3625 * when implementing new types of closures.
3627 * Returns: (transfer full): a newly allocated #GClosure
3630 g_closure_new_object (guint sizeof_closure,
3635 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
3636 g_return_val_if_fail (object->ref_count > 0, NULL); /* this doesn't work on finalizing objects */
3638 closure = g_closure_new_simple (sizeof_closure, object);
3639 g_object_watch_closure (object, closure);
3645 * g_cclosure_new_object: (skip)
3646 * @callback_func: the function to invoke
3647 * @object: a #GObject pointer to pass to @callback_func
3649 * A variant of g_cclosure_new() which uses @object as @user_data and
3650 * calls g_object_watch_closure() on @object and the created
3651 * closure. This function is useful when you have a callback closely
3652 * associated with a #GObject, and want the callback to no longer run
3653 * after the object is is freed.
3655 * Returns: a new #GCClosure
3658 g_cclosure_new_object (GCallback callback_func,
3663 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
3664 g_return_val_if_fail (object->ref_count > 0, NULL); /* this doesn't work on finalizing objects */
3665 g_return_val_if_fail (callback_func != NULL, NULL);
3667 closure = g_cclosure_new (callback_func, object, NULL);
3668 g_object_watch_closure (object, closure);
3674 * g_cclosure_new_object_swap: (skip)
3675 * @callback_func: the function to invoke
3676 * @object: a #GObject pointer to pass to @callback_func
3678 * A variant of g_cclosure_new_swap() which uses @object as @user_data
3679 * and calls g_object_watch_closure() on @object and the created
3680 * closure. This function is useful when you have a callback closely
3681 * associated with a #GObject, and want the callback to no longer run
3682 * after the object is is freed.
3684 * Returns: a new #GCClosure
3687 g_cclosure_new_object_swap (GCallback callback_func,
3692 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
3693 g_return_val_if_fail (object->ref_count > 0, NULL); /* this doesn't work on finalizing objects */
3694 g_return_val_if_fail (callback_func != NULL, NULL);
3696 closure = g_cclosure_new_swap (callback_func, object, NULL);
3697 g_object_watch_closure (object, closure);
3703 g_object_compat_control (gsize what,
3709 case 1: /* floating base type */
3710 return G_TYPE_INITIALLY_UNOWNED;
3711 case 2: /* FIXME: remove this once GLib/Gtk+ break ABI again */
3712 floating_flag_handler = (guint(*)(GObject*,gint)) data;
3714 case 3: /* FIXME: remove this once GLib/Gtk+ break ABI again */
3716 *pp = floating_flag_handler;
3723 G_DEFINE_TYPE (GInitiallyUnowned, g_initially_unowned, G_TYPE_OBJECT);
3726 g_initially_unowned_init (GInitiallyUnowned *object)
3728 g_object_force_floating (object);
3732 g_initially_unowned_class_init (GInitiallyUnownedClass *klass)