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 g_return_if_fail (pspec->flags & (G_PARAM_READABLE | G_PARAM_WRITABLE));
711 if (pspec->flags & G_PARAM_CONSTRUCT)
712 g_return_if_fail ((pspec->flags & G_PARAM_CONSTRUCT_ONLY) == 0);
713 if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))
714 g_return_if_fail (pspec->flags & G_PARAM_WRITABLE);
716 install_property_internal (iface_class->g_type, 0, pspec);
720 * g_object_class_find_property:
721 * @oclass: a #GObjectClass
722 * @property_name: the name of the property to look up
724 * Looks up the #GParamSpec for a property of a class.
726 * Returns: (transfer none): the #GParamSpec for the property, or
727 * %NULL if the class doesn't have a property of that name
730 g_object_class_find_property (GObjectClass *class,
731 const gchar *property_name)
734 GParamSpec *redirect;
736 g_return_val_if_fail (G_IS_OBJECT_CLASS (class), NULL);
737 g_return_val_if_fail (property_name != NULL, NULL);
739 pspec = g_param_spec_pool_lookup (pspec_pool,
741 G_OBJECT_CLASS_TYPE (class),
745 redirect = g_param_spec_get_redirect_target (pspec);
756 * g_object_interface_find_property:
757 * @g_iface: any interface vtable for the interface, or the default
758 * vtable for the interface
759 * @property_name: name of a property to lookup.
761 * Find the #GParamSpec with the given name for an
762 * interface. Generally, the interface vtable passed in as @g_iface
763 * will be the default vtable from g_type_default_interface_ref(), or,
764 * if you know the interface has already been loaded,
765 * g_type_default_interface_peek().
769 * Returns: (transfer none): the #GParamSpec for the property of the
770 * interface with the name @property_name, or %NULL if no
771 * such property exists.
774 g_object_interface_find_property (gpointer g_iface,
775 const gchar *property_name)
777 GTypeInterface *iface_class = g_iface;
779 g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface_class->g_type), NULL);
780 g_return_val_if_fail (property_name != NULL, NULL);
782 return g_param_spec_pool_lookup (pspec_pool,
789 * g_object_class_override_property:
790 * @oclass: a #GObjectClass
791 * @property_id: the new property ID
792 * @name: the name of a property registered in a parent class or
793 * in an interface of this class.
795 * Registers @property_id as referring to a property with the
796 * name @name in a parent class or in an interface implemented
797 * by @oclass. This allows this class to <firstterm>override</firstterm>
798 * a property implementation in a parent class or to provide
799 * the implementation of a property from an interface.
802 * Internally, overriding is implemented by creating a property of type
803 * #GParamSpecOverride; generally operations that query the properties of
804 * the object class, such as g_object_class_find_property() or
805 * g_object_class_list_properties() will return the overridden
806 * property. However, in one case, the @construct_properties argument of
807 * the @constructor virtual function, the #GParamSpecOverride is passed
808 * instead, so that the @param_id field of the #GParamSpec will be
809 * correct. For virtually all uses, this makes no difference. If you
810 * need to get the overridden property, you can call
811 * g_param_spec_get_redirect_target().
817 g_object_class_override_property (GObjectClass *oclass,
821 GParamSpec *overridden = NULL;
825 g_return_if_fail (G_IS_OBJECT_CLASS (oclass));
826 g_return_if_fail (property_id > 0);
827 g_return_if_fail (name != NULL);
829 /* Find the overridden property; first check parent types
831 parent_type = g_type_parent (G_OBJECT_CLASS_TYPE (oclass));
832 if (parent_type != G_TYPE_NONE)
833 overridden = g_param_spec_pool_lookup (pspec_pool,
842 /* Now check interfaces
844 ifaces = g_type_interfaces (G_OBJECT_CLASS_TYPE (oclass), &n_ifaces);
845 while (n_ifaces-- && !overridden)
847 overridden = g_param_spec_pool_lookup (pspec_pool,
858 g_warning ("%s: Can't find property to override for '%s::%s'",
859 G_STRFUNC, G_OBJECT_CLASS_NAME (oclass), name);
863 new = g_param_spec_override (name, overridden);
864 g_object_class_install_property (oclass, property_id, new);
868 * g_object_class_list_properties:
869 * @oclass: a #GObjectClass
870 * @n_properties: (out): return location for the length of the returned array
872 * Get an array of #GParamSpec* for all properties of a class.
874 * Returns: (array length=n_properties) (transfer container): an array of
875 * #GParamSpec* which should be freed after use
877 GParamSpec** /* free result */
878 g_object_class_list_properties (GObjectClass *class,
879 guint *n_properties_p)
884 g_return_val_if_fail (G_IS_OBJECT_CLASS (class), NULL);
886 pspecs = g_param_spec_pool_list (pspec_pool,
887 G_OBJECT_CLASS_TYPE (class),
896 * g_object_interface_list_properties:
897 * @g_iface: any interface vtable for the interface, or the default
898 * vtable for the interface
899 * @n_properties_p: (out): location to store number of properties returned.
901 * Lists the properties of an interface.Generally, the interface
902 * vtable passed in as @g_iface will be the default vtable from
903 * g_type_default_interface_ref(), or, if you know the interface has
904 * already been loaded, g_type_default_interface_peek().
908 * Returns: (array length=n_properties_p) (transfer container): a
909 * pointer to an array of pointers to #GParamSpec
910 * structures. The paramspecs are owned by GLib, but the
911 * array should be freed with g_free() when you are done with
915 g_object_interface_list_properties (gpointer g_iface,
916 guint *n_properties_p)
918 GTypeInterface *iface_class = g_iface;
922 g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface_class->g_type), NULL);
924 pspecs = g_param_spec_pool_list (pspec_pool,
934 g_object_init (GObject *object,
937 object->ref_count = 1;
938 object->qdata = NULL;
940 if (CLASS_HAS_PROPS (class))
942 /* freeze object's notification queue, g_object_newv() preserves pairedness */
943 g_object_notify_queue_freeze (object, FALSE);
946 if (CLASS_HAS_CUSTOM_CONSTRUCTOR (class))
948 /* enter construction list for notify_queue_thaw() and to allow construct-only properties */
949 G_LOCK (construction_mutex);
950 construction_objects = g_slist_prepend (construction_objects, object);
951 G_UNLOCK (construction_mutex);
954 #ifdef G_ENABLE_DEBUG
957 G_LOCK (debug_objects);
958 debug_objects_count++;
959 g_hash_table_insert (debug_objects_ht, object, object);
960 G_UNLOCK (debug_objects);
962 #endif /* G_ENABLE_DEBUG */
966 g_object_do_set_property (GObject *object,
974 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
980 g_object_do_get_property (GObject *object,
988 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
994 g_object_real_dispose (GObject *object)
996 g_signal_handlers_destroy (object);
997 g_datalist_id_set_data (&object->qdata, quark_closure_array, NULL);
998 g_datalist_id_set_data (&object->qdata, quark_weak_refs, NULL);
1002 g_object_finalize (GObject *object)
1004 g_datalist_clear (&object->qdata);
1006 #ifdef G_ENABLE_DEBUG
1009 G_LOCK (debug_objects);
1010 g_assert (g_hash_table_lookup (debug_objects_ht, object) == object);
1011 g_hash_table_remove (debug_objects_ht, object);
1012 debug_objects_count--;
1013 G_UNLOCK (debug_objects);
1015 #endif /* G_ENABLE_DEBUG */
1020 g_object_dispatch_properties_changed (GObject *object,
1022 GParamSpec **pspecs)
1026 for (i = 0; i < n_pspecs; i++)
1027 g_signal_emit (object, gobject_signals[NOTIFY], g_quark_from_string (pspecs[i]->name), pspecs[i]);
1031 * g_object_run_dispose:
1032 * @object: a #GObject
1034 * Releases all references to other objects. This can be used to break
1037 * This functions should only be called from object system implementations.
1040 g_object_run_dispose (GObject *object)
1042 g_return_if_fail (G_IS_OBJECT (object));
1043 g_return_if_fail (object->ref_count > 0);
1045 g_object_ref (object);
1046 TRACE (GOBJECT_OBJECT_DISPOSE(object,G_TYPE_FROM_INSTANCE(object), 0));
1047 G_OBJECT_GET_CLASS (object)->dispose (object);
1048 TRACE (GOBJECT_OBJECT_DISPOSE_END(object,G_TYPE_FROM_INSTANCE(object), 0));
1049 g_object_unref (object);
1053 * g_object_freeze_notify:
1054 * @object: a #GObject
1056 * Increases the freeze count on @object. If the freeze count is
1057 * non-zero, the emission of "notify" signals on @object is
1058 * stopped. The signals are queued until the freeze count is decreased
1061 * This is necessary for accessors that modify multiple properties to prevent
1062 * premature notification while the object is still being modified.
1065 g_object_freeze_notify (GObject *object)
1067 g_return_if_fail (G_IS_OBJECT (object));
1069 if (g_atomic_int_get (&object->ref_count) == 0)
1072 g_object_ref (object);
1073 g_object_notify_queue_freeze (object, FALSE);
1074 g_object_unref (object);
1078 get_notify_pspec (GParamSpec *pspec)
1080 GParamSpec *redirected;
1082 /* we don't notify on non-READABLE parameters */
1083 if (~pspec->flags & G_PARAM_READABLE)
1086 /* if the paramspec is redirected, notify on the target */
1087 redirected = g_param_spec_get_redirect_target (pspec);
1088 if (redirected != NULL)
1091 /* else, notify normally */
1096 g_object_notify_by_spec_internal (GObject *object,
1099 GParamSpec *notify_pspec;
1101 notify_pspec = get_notify_pspec (pspec);
1103 if (notify_pspec != NULL)
1105 GObjectNotifyQueue *nqueue;
1107 /* conditional freeze: only increase freeze count if already frozen */
1108 nqueue = g_object_notify_queue_freeze (object, TRUE);
1112 /* we're frozen, so add to the queue and release our freeze */
1113 g_object_notify_queue_add (object, nqueue, notify_pspec);
1114 g_object_notify_queue_thaw (object, nqueue);
1117 /* not frozen, so just dispatch the notification directly */
1118 G_OBJECT_GET_CLASS (object)
1119 ->dispatch_properties_changed (object, 1, ¬ify_pspec);
1125 * @object: a #GObject
1126 * @property_name: the name of a property installed on the class of @object.
1128 * Emits a "notify" signal for the property @property_name on @object.
1130 * When possible, eg. when signaling a property change from within the class
1131 * that registered the property, you should use g_object_notify_by_pspec()
1135 g_object_notify (GObject *object,
1136 const gchar *property_name)
1140 g_return_if_fail (G_IS_OBJECT (object));
1141 g_return_if_fail (property_name != NULL);
1142 if (g_atomic_int_get (&object->ref_count) == 0)
1145 g_object_ref (object);
1146 /* We don't need to get the redirect target
1147 * (by, e.g. calling g_object_class_find_property())
1148 * because g_object_notify_queue_add() does that
1150 pspec = g_param_spec_pool_lookup (pspec_pool,
1152 G_OBJECT_TYPE (object),
1156 g_warning ("%s: object class `%s' has no property named `%s'",
1158 G_OBJECT_TYPE_NAME (object),
1161 g_object_notify_by_spec_internal (object, pspec);
1162 g_object_unref (object);
1166 * g_object_notify_by_pspec:
1167 * @object: a #GObject
1168 * @pspec: the #GParamSpec of a property installed on the class of @object.
1170 * Emits a "notify" signal for the property specified by @pspec on @object.
1172 * This function omits the property name lookup, hence it is faster than
1173 * g_object_notify().
1175 * One way to avoid using g_object_notify() from within the
1176 * class that registered the properties, and using g_object_notify_by_pspec()
1177 * instead, is to store the GParamSpec used with
1178 * g_object_class_install_property() inside a static array, e.g.:
1188 * static GParamSpec *properties[PROP_LAST];
1191 * my_object_class_init (MyObjectClass *klass)
1193 * properties[PROP_FOO] = g_param_spec_int ("foo", "Foo", "The foo",
1196 * G_PARAM_READWRITE);
1197 * g_object_class_install_property (gobject_class,
1199 * properties[PROP_FOO]);
1203 * and then notify a change on the "foo" property with:
1206 * g_object_notify_by_pspec (self, properties[PROP_FOO]);
1212 g_object_notify_by_pspec (GObject *object,
1216 g_return_if_fail (G_IS_OBJECT (object));
1217 g_return_if_fail (G_IS_PARAM_SPEC (pspec));
1219 g_object_ref (object);
1220 g_object_notify_by_spec_internal (object, pspec);
1221 g_object_unref (object);
1225 * g_object_thaw_notify:
1226 * @object: a #GObject
1228 * Reverts the effect of a previous call to
1229 * g_object_freeze_notify(). The freeze count is decreased on @object
1230 * and when it reaches zero, all queued "notify" signals are emitted.
1232 * It is an error to call this function when the freeze count is zero.
1235 g_object_thaw_notify (GObject *object)
1237 GObjectNotifyQueue *nqueue;
1239 g_return_if_fail (G_IS_OBJECT (object));
1240 if (g_atomic_int_get (&object->ref_count) == 0)
1243 g_object_ref (object);
1245 /* FIXME: Freezing is the only way to get at the notify queue.
1246 * So we freeze once and then thaw twice.
1248 nqueue = g_object_notify_queue_freeze (object, FALSE);
1249 g_object_notify_queue_thaw (object, nqueue);
1250 g_object_notify_queue_thaw (object, nqueue);
1252 g_object_unref (object);
1256 object_get_property (GObject *object,
1260 GObjectClass *class = g_type_class_peek (pspec->owner_type);
1261 guint param_id = PARAM_SPEC_PARAM_ID (pspec);
1262 GParamSpec *redirect;
1266 g_warning ("'%s::%s' is not a valid property name; '%s' is not a GObject subtype",
1267 g_type_name (pspec->owner_type), pspec->name, g_type_name (pspec->owner_type));
1271 redirect = g_param_spec_get_redirect_target (pspec);
1275 class->get_property (object, param_id, value, pspec);
1279 object_set_property (GObject *object,
1281 const GValue *value,
1282 GObjectNotifyQueue *nqueue)
1284 GValue tmp_value = G_VALUE_INIT;
1285 GObjectClass *class = g_type_class_peek (pspec->owner_type);
1286 guint param_id = PARAM_SPEC_PARAM_ID (pspec);
1287 GParamSpec *redirect;
1288 static const gchar * enable_diagnostic = NULL;
1292 g_warning ("'%s::%s' is not a valid property name; '%s' is not a GObject subtype",
1293 g_type_name (pspec->owner_type), pspec->name, g_type_name (pspec->owner_type));
1297 redirect = g_param_spec_get_redirect_target (pspec);
1301 if (G_UNLIKELY (!enable_diagnostic))
1303 enable_diagnostic = g_getenv ("G_ENABLE_DIAGNOSTIC");
1304 if (!enable_diagnostic)
1305 enable_diagnostic = "0";
1308 if (enable_diagnostic[0] == '1')
1310 if (pspec->flags & G_PARAM_DEPRECATED)
1311 g_warning ("The property %s:%s is deprecated and shouldn't be used "
1312 "anymore. It will be removed in a future version.",
1313 G_OBJECT_TYPE_NAME (object), pspec->name);
1316 /* provide a copy to work from, convert (if necessary) and validate */
1317 g_value_init (&tmp_value, pspec->value_type);
1318 if (!g_value_transform (value, &tmp_value))
1319 g_warning ("unable to set property `%s' of type `%s' from value of type `%s'",
1321 g_type_name (pspec->value_type),
1322 G_VALUE_TYPE_NAME (value));
1323 else if (g_param_value_validate (pspec, &tmp_value) && !(pspec->flags & G_PARAM_LAX_VALIDATION))
1325 gchar *contents = g_strdup_value_contents (value);
1327 g_warning ("value \"%s\" of type `%s' is invalid or out of range for property `%s' of type `%s'",
1329 G_VALUE_TYPE_NAME (value),
1331 g_type_name (pspec->value_type));
1336 GParamSpec *notify_pspec;
1338 class->set_property (object, param_id, &tmp_value, pspec);
1340 notify_pspec = get_notify_pspec (pspec);
1342 if (notify_pspec != NULL)
1343 g_object_notify_queue_add (object, nqueue, notify_pspec);
1345 g_value_unset (&tmp_value);
1349 object_interface_check_properties (gpointer func_data,
1352 GTypeInterface *iface_class = g_iface;
1353 GObjectClass *class;
1354 GType iface_type = iface_class->g_type;
1355 GParamSpec **pspecs;
1358 class = g_type_class_ref (iface_class->g_instance_type);
1360 if (!G_IS_OBJECT_CLASS (class))
1363 pspecs = g_param_spec_pool_list (pspec_pool, iface_type, &n);
1367 GParamSpec *class_pspec = g_param_spec_pool_lookup (pspec_pool,
1369 G_OBJECT_CLASS_TYPE (class),
1374 g_critical ("Object class %s doesn't implement property "
1375 "'%s' from interface '%s'",
1376 g_type_name (G_OBJECT_CLASS_TYPE (class)),
1378 g_type_name (iface_type));
1383 /* We do a number of checks on the properties of an interface to
1384 * make sure that all classes implementing the interface are
1385 * overriding the properties in a sane way.
1387 * We do the checks in order of importance so that we can give
1388 * more useful error messages first.
1390 * First, we check that the implementation doesn't remove the
1391 * basic functionality (readability, writability) advertised by
1392 * the interface. Next, we check that it doesn't introduce
1393 * additional restrictions (such as construct-only). Finally, we
1394 * make sure the types are compatible.
1397 #define SUBSET(a,b,mask) (((a) & ~(b) & (mask)) == 0)
1398 /* If the property on the interface is readable then the
1399 * implementation must be readable. If the interface is writable
1400 * then the implementation must be writable.
1402 if (!SUBSET (pspecs[n]->flags, class_pspec->flags, G_PARAM_READABLE | G_PARAM_WRITABLE))
1404 g_critical ("Flags for property '%s' on class '%s' remove functionality compared with the "
1405 "property on interface '%s'\n", pspecs[n]->name,
1406 g_type_name (G_OBJECT_CLASS_TYPE (class)), g_type_name (iface_type));
1410 /* If the property on the interface is writable then we need to
1411 * make sure the implementation doesn't introduce new restrictions
1412 * on that writability (ie: construct-only).
1414 * If the interface was not writable to begin with then we don't
1415 * really have any problems here because "writable at construct
1416 * type only" is still more permissive than "read only".
1418 if (pspecs[n]->flags & G_PARAM_WRITABLE)
1420 if (!SUBSET (class_pspec->flags, pspecs[n]->flags, G_PARAM_CONSTRUCT_ONLY))
1422 g_critical ("Flags for property '%s' on class '%s' introduce additional restrictions on "
1423 "writability compared with the property on interface '%s'\n", pspecs[n]->name,
1424 g_type_name (G_OBJECT_CLASS_TYPE (class)), g_type_name (iface_type));
1430 /* If the property on the interface is readable then we are
1431 * effectively advertising that reading the property will return a
1432 * value of a specific type. All implementations of the interface
1433 * need to return items of this type -- but may be more
1434 * restrictive. For example, it is legal to have:
1436 * GtkWidget *get_item();
1438 * that is implemented by a function that always returns a
1439 * GtkEntry. In short: readability implies that the
1440 * implementation value type must be equal or more restrictive.
1442 * Similarly, if the property on the interface is writable then
1443 * must be able to accept the property being set to any value of
1444 * that type, including subclasses. In this case, we may also be
1445 * less restrictive. For example, it is legal to have:
1447 * set_item (GtkEntry *);
1449 * that is implemented by a function that will actually work with
1450 * any GtkWidget. In short: writability implies that the
1451 * implementation value type must be equal or less restrictive.
1453 * In the case that the property is both readable and writable
1454 * then the only way that both of the above can be satisfied is
1455 * with a type that is exactly equal.
1457 switch (pspecs[n]->flags & (G_PARAM_READABLE | G_PARAM_WRITABLE))
1459 case G_PARAM_READABLE | G_PARAM_WRITABLE:
1460 /* class pspec value type must have exact equality with interface */
1461 if (pspecs[n]->value_type != class_pspec->value_type)
1462 g_critical ("Read/writable property '%s' on class '%s' has type '%s' which is not exactly equal to the "
1463 "type '%s' of the property on the interface '%s'\n", pspecs[n]->name,
1464 g_type_name (G_OBJECT_CLASS_TYPE (class)), g_type_name (G_PARAM_SPEC_VALUE_TYPE (class_pspec)),
1465 g_type_name (G_PARAM_SPEC_VALUE_TYPE (pspecs[n])), g_type_name (iface_type));
1468 case G_PARAM_READABLE:
1469 /* class pspec value type equal or more restrictive than interface */
1470 if (!g_type_is_a (class_pspec->value_type, pspecs[n]->value_type))
1471 g_critical ("Read-only property '%s' on class '%s' has type '%s' which is not equal to or more "
1472 "restrictive than the type '%s' of the property on the interface '%s'\n", pspecs[n]->name,
1473 g_type_name (G_OBJECT_CLASS_TYPE (class)), g_type_name (G_PARAM_SPEC_VALUE_TYPE (class_pspec)),
1474 g_type_name (G_PARAM_SPEC_VALUE_TYPE (pspecs[n])), g_type_name (iface_type));
1477 case G_PARAM_WRITABLE:
1478 /* class pspec value type equal or less restrictive than interface */
1479 if (!g_type_is_a (pspecs[n]->value_type, class_pspec->value_type))
1480 g_critical ("Write-only property '%s' on class '%s' has type '%s' which is not equal to or less "
1481 "restrictive than the type '%s' of the property on the interface '%s' \n", pspecs[n]->name,
1482 g_type_name (G_OBJECT_CLASS_TYPE (class)), g_type_name (G_PARAM_SPEC_VALUE_TYPE (class_pspec)),
1483 g_type_name (G_PARAM_SPEC_VALUE_TYPE (pspecs[n])), g_type_name (iface_type));
1487 g_assert_not_reached ();
1493 g_type_class_unref (class);
1497 g_object_get_type (void)
1499 return G_TYPE_OBJECT;
1503 * g_object_new: (skip)
1504 * @object_type: the type id of the #GObject subtype to instantiate
1505 * @first_property_name: the name of the first property
1506 * @...: the value of the first property, followed optionally by more
1507 * name/value pairs, followed by %NULL
1509 * Creates a new instance of a #GObject subtype and sets its properties.
1511 * Construction parameters (see #G_PARAM_CONSTRUCT, #G_PARAM_CONSTRUCT_ONLY)
1512 * which are not explicitly specified are set to their default values.
1514 * Returns: (transfer full): a new instance of @object_type
1517 g_object_new (GType object_type,
1518 const gchar *first_property_name,
1524 g_return_val_if_fail (G_TYPE_IS_OBJECT (object_type), NULL);
1526 /* short circuit for calls supplying no properties */
1527 if (!first_property_name)
1528 return g_object_newv (object_type, 0, NULL);
1530 va_start (var_args, first_property_name);
1531 object = g_object_new_valist (object_type, first_property_name, var_args);
1538 slist_maybe_remove (GSList **slist,
1541 GSList *last = NULL, *node = *slist;
1544 if (node->data == data)
1547 last->next = node->next;
1549 *slist = node->next;
1550 g_slist_free_1 (node);
1559 static inline gboolean
1560 object_in_construction_list (GObject *object)
1562 gboolean in_construction;
1563 G_LOCK (construction_mutex);
1564 in_construction = g_slist_find (construction_objects, object) != NULL;
1565 G_UNLOCK (construction_mutex);
1566 return in_construction;
1571 * @object_type: the type id of the #GObject subtype to instantiate
1572 * @n_parameters: the length of the @parameters array
1573 * @parameters: (array length=n_parameters): an array of #GParameter
1575 * Creates a new instance of a #GObject subtype and sets its properties.
1577 * Construction parameters (see #G_PARAM_CONSTRUCT, #G_PARAM_CONSTRUCT_ONLY)
1578 * which are not explicitly specified are set to their default values.
1580 * Rename to: g_object_new
1581 * Returns: (type GObject.Object) (transfer full): a new instance of
1585 g_object_newv (GType object_type,
1587 GParameter *parameters)
1589 GObjectConstructParam *cparams = NULL, *oparams;
1590 GObjectNotifyQueue *nqueue = NULL; /* shouldn't be initialized, just to silence compiler */
1592 GObjectClass *class, *unref_class = NULL;
1594 guint n_total_cparams = 0, n_cparams = 0, n_oparams = 0, n_cvalues;
1596 GList *clist = NULL;
1597 gboolean newly_constructed;
1600 g_return_val_if_fail (G_TYPE_IS_OBJECT (object_type), NULL);
1602 class = g_type_class_peek_static (object_type);
1604 class = unref_class = g_type_class_ref (object_type);
1605 for (slist = class->construct_properties; slist; slist = slist->next)
1607 clist = g_list_prepend (clist, slist->data);
1608 n_total_cparams += 1;
1611 if (n_parameters == 0 && n_total_cparams == 0)
1613 /* This is a simple object with no construct properties, and
1614 * no properties are being set, so short circuit the parameter
1615 * handling. This speeds up simple object construction.
1618 object = class->constructor (object_type, 0, NULL);
1619 goto did_construction;
1622 /* collect parameters, sort into construction and normal ones */
1623 oparams = g_new (GObjectConstructParam, n_parameters);
1624 cparams = g_new (GObjectConstructParam, n_total_cparams);
1625 for (i = 0; i < n_parameters; i++)
1627 GValue *value = ¶meters[i].value;
1628 GParamSpec *pspec = g_param_spec_pool_lookup (pspec_pool,
1634 g_warning ("%s: object class `%s' has no property named `%s'",
1636 g_type_name (object_type),
1637 parameters[i].name);
1640 if (!(pspec->flags & G_PARAM_WRITABLE))
1642 g_warning ("%s: property `%s' of object class `%s' is not writable",
1645 g_type_name (object_type));
1648 if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))
1650 GList *list = g_list_find (clist, pspec);
1654 g_warning ("%s: construct property \"%s\" for object `%s' can't be set twice",
1655 G_STRFUNC, pspec->name, g_type_name (object_type));
1658 cparams[n_cparams].pspec = pspec;
1659 cparams[n_cparams].value = value;
1664 list->prev->next = list->next;
1666 list->next->prev = list->prev;
1667 g_list_free_1 (list);
1671 oparams[n_oparams].pspec = pspec;
1672 oparams[n_oparams].value = value;
1677 /* set remaining construction properties to default values */
1678 n_cvalues = n_total_cparams - n_cparams;
1679 cvalues = g_new (GValue, n_cvalues);
1682 GList *tmp = clist->next;
1683 GParamSpec *pspec = clist->data;
1684 GValue *value = cvalues + n_total_cparams - n_cparams - 1;
1687 g_value_init (value, pspec->value_type);
1688 g_param_value_set_default (pspec, value);
1690 cparams[n_cparams].pspec = pspec;
1691 cparams[n_cparams].value = value;
1694 g_list_free_1 (clist);
1698 /* construct object from construction parameters */
1699 object = class->constructor (object_type, n_total_cparams, cparams);
1700 /* free construction values */
1703 g_value_unset (cvalues + n_cvalues);
1707 if (CLASS_HAS_CUSTOM_CONSTRUCTOR (class))
1709 /* adjust freeze_count according to g_object_init() and remaining properties */
1710 G_LOCK (construction_mutex);
1711 newly_constructed = slist_maybe_remove (&construction_objects, object);
1712 G_UNLOCK (construction_mutex);
1715 newly_constructed = TRUE;
1717 if (CLASS_HAS_PROPS (class))
1719 if (newly_constructed || n_oparams)
1720 nqueue = g_object_notify_queue_freeze (object, FALSE);
1721 if (newly_constructed)
1722 g_object_notify_queue_thaw (object, nqueue);
1725 /* run 'constructed' handler if there is a custom one */
1726 if (newly_constructed && CLASS_HAS_CUSTOM_CONSTRUCTED (class))
1727 class->constructed (object);
1729 /* set remaining properties */
1730 for (i = 0; i < n_oparams; i++)
1731 object_set_property (object, oparams[i].pspec, oparams[i].value, nqueue);
1734 if (CLASS_HAS_PROPS (class))
1736 /* release our own freeze count and handle notifications */
1737 if (newly_constructed || n_oparams)
1738 g_object_notify_queue_thaw (object, nqueue);
1742 g_type_class_unref (unref_class);
1748 * g_object_new_valist: (skip)
1749 * @object_type: the type id of the #GObject subtype to instantiate
1750 * @first_property_name: the name of the first property
1751 * @var_args: the value of the first property, followed optionally by more
1752 * name/value pairs, followed by %NULL
1754 * Creates a new instance of a #GObject subtype and sets its properties.
1756 * Construction parameters (see #G_PARAM_CONSTRUCT, #G_PARAM_CONSTRUCT_ONLY)
1757 * which are not explicitly specified are set to their default values.
1759 * Returns: a new instance of @object_type
1762 g_object_new_valist (GType object_type,
1763 const gchar *first_property_name,
1766 GObjectClass *class;
1770 guint n_params = 0, n_alloced_params = 16;
1772 g_return_val_if_fail (G_TYPE_IS_OBJECT (object_type), NULL);
1774 if (!first_property_name)
1775 return g_object_newv (object_type, 0, NULL);
1777 class = g_type_class_ref (object_type);
1779 params = g_new0 (GParameter, n_alloced_params);
1780 name = first_property_name;
1783 gchar *error = NULL;
1784 GParamSpec *pspec = g_param_spec_pool_lookup (pspec_pool,
1790 g_warning ("%s: object class `%s' has no property named `%s'",
1792 g_type_name (object_type),
1796 if (n_params >= n_alloced_params)
1798 n_alloced_params += 16;
1799 params = g_renew (GParameter, params, n_alloced_params);
1800 memset (params + n_params, 0, 16 * (sizeof *params));
1802 params[n_params].name = name;
1803 G_VALUE_COLLECT_INIT (¶ms[n_params].value, pspec->value_type,
1804 var_args, 0, &error);
1807 g_warning ("%s: %s", G_STRFUNC, error);
1809 g_value_unset (¶ms[n_params].value);
1813 name = va_arg (var_args, gchar*);
1816 object = g_object_newv (object_type, n_params, params);
1819 g_value_unset (¶ms[n_params].value);
1822 g_type_class_unref (class);
1828 g_object_constructor (GType type,
1829 guint n_construct_properties,
1830 GObjectConstructParam *construct_params)
1835 object = (GObject*) g_type_create_instance (type);
1837 /* set construction parameters */
1838 if (n_construct_properties)
1840 GObjectNotifyQueue *nqueue = g_object_notify_queue_freeze (object, FALSE);
1842 /* set construct properties */
1843 while (n_construct_properties--)
1845 GValue *value = construct_params->value;
1846 GParamSpec *pspec = construct_params->pspec;
1849 object_set_property (object, pspec, value, nqueue);
1851 g_object_notify_queue_thaw (object, nqueue);
1852 /* the notification queue is still frozen from g_object_init(), so
1853 * we don't need to handle it here, g_object_newv() takes
1862 g_object_constructed (GObject *object)
1864 /* empty default impl to allow unconditional upchaining */
1868 * g_object_set_valist: (skip)
1869 * @object: a #GObject
1870 * @first_property_name: name of the first property to set
1871 * @var_args: value for the first property, followed optionally by more
1872 * name/value pairs, followed by %NULL
1874 * Sets properties on an object.
1877 g_object_set_valist (GObject *object,
1878 const gchar *first_property_name,
1881 GObjectNotifyQueue *nqueue;
1884 g_return_if_fail (G_IS_OBJECT (object));
1886 g_object_ref (object);
1887 nqueue = g_object_notify_queue_freeze (object, FALSE);
1889 name = first_property_name;
1892 GValue value = G_VALUE_INIT;
1894 gchar *error = NULL;
1896 pspec = g_param_spec_pool_lookup (pspec_pool,
1898 G_OBJECT_TYPE (object),
1902 g_warning ("%s: object class `%s' has no property named `%s'",
1904 G_OBJECT_TYPE_NAME (object),
1908 if (!(pspec->flags & G_PARAM_WRITABLE))
1910 g_warning ("%s: property `%s' of object class `%s' is not writable",
1913 G_OBJECT_TYPE_NAME (object));
1916 if ((pspec->flags & G_PARAM_CONSTRUCT_ONLY) && !object_in_construction_list (object))
1918 g_warning ("%s: construct property \"%s\" for object `%s' can't be set after construction",
1919 G_STRFUNC, pspec->name, G_OBJECT_TYPE_NAME (object));
1923 G_VALUE_COLLECT_INIT (&value, pspec->value_type, var_args,
1927 g_warning ("%s: %s", G_STRFUNC, error);
1929 g_value_unset (&value);
1933 object_set_property (object, pspec, &value, nqueue);
1934 g_value_unset (&value);
1936 name = va_arg (var_args, gchar*);
1939 g_object_notify_queue_thaw (object, nqueue);
1940 g_object_unref (object);
1944 * g_object_get_valist: (skip)
1945 * @object: a #GObject
1946 * @first_property_name: name of the first property to get
1947 * @var_args: return location for the first property, followed optionally by more
1948 * name/return location pairs, followed by %NULL
1950 * Gets properties of an object.
1952 * In general, a copy is made of the property contents and the caller
1953 * is responsible for freeing the memory in the appropriate manner for
1954 * the type, for instance by calling g_free() or g_object_unref().
1956 * See g_object_get().
1959 g_object_get_valist (GObject *object,
1960 const gchar *first_property_name,
1965 g_return_if_fail (G_IS_OBJECT (object));
1967 g_object_ref (object);
1969 name = first_property_name;
1973 GValue value = G_VALUE_INIT;
1977 pspec = g_param_spec_pool_lookup (pspec_pool,
1979 G_OBJECT_TYPE (object),
1983 g_warning ("%s: object class `%s' has no property named `%s'",
1985 G_OBJECT_TYPE_NAME (object),
1989 if (!(pspec->flags & G_PARAM_READABLE))
1991 g_warning ("%s: property `%s' of object class `%s' is not readable",
1994 G_OBJECT_TYPE_NAME (object));
1998 g_value_init (&value, pspec->value_type);
2000 object_get_property (object, pspec, &value);
2002 G_VALUE_LCOPY (&value, var_args, 0, &error);
2005 g_warning ("%s: %s", G_STRFUNC, error);
2007 g_value_unset (&value);
2011 g_value_unset (&value);
2013 name = va_arg (var_args, gchar*);
2016 g_object_unref (object);
2020 * g_object_set: (skip)
2021 * @object: a #GObject
2022 * @first_property_name: name of the first property to set
2023 * @...: value for the first property, followed optionally by more
2024 * name/value pairs, followed by %NULL
2026 * Sets properties on an object.
2029 g_object_set (gpointer _object,
2030 const gchar *first_property_name,
2033 GObject *object = _object;
2036 g_return_if_fail (G_IS_OBJECT (object));
2038 va_start (var_args, first_property_name);
2039 g_object_set_valist (object, first_property_name, var_args);
2044 * g_object_get: (skip)
2045 * @object: a #GObject
2046 * @first_property_name: name of the first property to get
2047 * @...: return location for the first property, followed optionally by more
2048 * name/return location pairs, followed by %NULL
2050 * Gets properties of an object.
2052 * In general, a copy is made of the property contents and the caller
2053 * is responsible for freeing the memory in the appropriate manner for
2054 * the type, for instance by calling g_free() or g_object_unref().
2057 * <title>Using g_object_get(<!-- -->)</title>
2058 * An example of using g_object_get() to get the contents
2059 * of three properties - one of type #G_TYPE_INT,
2060 * one of type #G_TYPE_STRING, and one of type #G_TYPE_OBJECT:
2066 * g_object_get (my_object,
2067 * "int-property", &intval,
2068 * "str-property", &strval,
2069 * "obj-property", &objval,
2072 * // Do something with intval, strval, objval
2075 * g_object_unref (objval);
2080 g_object_get (gpointer _object,
2081 const gchar *first_property_name,
2084 GObject *object = _object;
2087 g_return_if_fail (G_IS_OBJECT (object));
2089 va_start (var_args, first_property_name);
2090 g_object_get_valist (object, first_property_name, var_args);
2095 * g_object_set_property:
2096 * @object: a #GObject
2097 * @property_name: the name of the property to set
2100 * Sets a property on an object.
2103 g_object_set_property (GObject *object,
2104 const gchar *property_name,
2105 const GValue *value)
2107 GObjectNotifyQueue *nqueue;
2110 g_return_if_fail (G_IS_OBJECT (object));
2111 g_return_if_fail (property_name != NULL);
2112 g_return_if_fail (G_IS_VALUE (value));
2114 g_object_ref (object);
2115 nqueue = g_object_notify_queue_freeze (object, FALSE);
2117 pspec = g_param_spec_pool_lookup (pspec_pool,
2119 G_OBJECT_TYPE (object),
2122 g_warning ("%s: object class `%s' has no property named `%s'",
2124 G_OBJECT_TYPE_NAME (object),
2126 else if (!(pspec->flags & G_PARAM_WRITABLE))
2127 g_warning ("%s: property `%s' of object class `%s' is not writable",
2130 G_OBJECT_TYPE_NAME (object));
2131 else if ((pspec->flags & G_PARAM_CONSTRUCT_ONLY) && !object_in_construction_list (object))
2132 g_warning ("%s: construct property \"%s\" for object `%s' can't be set after construction",
2133 G_STRFUNC, pspec->name, G_OBJECT_TYPE_NAME (object));
2135 object_set_property (object, pspec, value, nqueue);
2137 g_object_notify_queue_thaw (object, nqueue);
2138 g_object_unref (object);
2142 * g_object_get_property:
2143 * @object: a #GObject
2144 * @property_name: the name of the property to get
2145 * @value: return location for the property value
2147 * Gets a property of an object. @value must have been initialized to the
2148 * expected type of the property (or a type to which the expected type can be
2149 * transformed) using g_value_init().
2151 * In general, a copy is made of the property contents and the caller is
2152 * responsible for freeing the memory by calling g_value_unset().
2154 * Note that g_object_get_property() is really intended for language
2155 * bindings, g_object_get() is much more convenient for C programming.
2158 g_object_get_property (GObject *object,
2159 const gchar *property_name,
2164 g_return_if_fail (G_IS_OBJECT (object));
2165 g_return_if_fail (property_name != NULL);
2166 g_return_if_fail (G_IS_VALUE (value));
2168 g_object_ref (object);
2170 pspec = g_param_spec_pool_lookup (pspec_pool,
2172 G_OBJECT_TYPE (object),
2175 g_warning ("%s: object class `%s' has no property named `%s'",
2177 G_OBJECT_TYPE_NAME (object),
2179 else if (!(pspec->flags & G_PARAM_READABLE))
2180 g_warning ("%s: property `%s' of object class `%s' is not readable",
2183 G_OBJECT_TYPE_NAME (object));
2186 GValue *prop_value, tmp_value = G_VALUE_INIT;
2188 /* auto-conversion of the callers value type
2190 if (G_VALUE_TYPE (value) == pspec->value_type)
2192 g_value_reset (value);
2195 else if (!g_value_type_transformable (pspec->value_type, G_VALUE_TYPE (value)))
2197 g_warning ("%s: can't retrieve property `%s' of type `%s' as value of type `%s'",
2198 G_STRFUNC, pspec->name,
2199 g_type_name (pspec->value_type),
2200 G_VALUE_TYPE_NAME (value));
2201 g_object_unref (object);
2206 g_value_init (&tmp_value, pspec->value_type);
2207 prop_value = &tmp_value;
2209 object_get_property (object, pspec, prop_value);
2210 if (prop_value != value)
2212 g_value_transform (prop_value, value);
2213 g_value_unset (&tmp_value);
2217 g_object_unref (object);
2221 * g_object_connect: (skip)
2222 * @object: a #GObject
2223 * @signal_spec: the spec for the first signal
2224 * @...: #GCallback for the first signal, followed by data for the
2225 * first signal, followed optionally by more signal
2226 * spec/callback/data triples, followed by %NULL
2228 * A convenience function to connect multiple signals at once.
2230 * The signal specs expected by this function have the form
2231 * "modifier::signal_name", where modifier can be one of the following:
2234 * <term>signal</term>
2236 * equivalent to <literal>g_signal_connect_data (..., NULL, 0)</literal>
2237 * </para></listitem>
2240 * <term>object_signal</term>
2241 * <term>object-signal</term>
2243 * equivalent to <literal>g_signal_connect_object (..., 0)</literal>
2244 * </para></listitem>
2247 * <term>swapped_signal</term>
2248 * <term>swapped-signal</term>
2250 * equivalent to <literal>g_signal_connect_data (..., NULL, G_CONNECT_SWAPPED)</literal>
2251 * </para></listitem>
2254 * <term>swapped_object_signal</term>
2255 * <term>swapped-object-signal</term>
2257 * equivalent to <literal>g_signal_connect_object (..., G_CONNECT_SWAPPED)</literal>
2258 * </para></listitem>
2261 * <term>signal_after</term>
2262 * <term>signal-after</term>
2264 * equivalent to <literal>g_signal_connect_data (..., NULL, G_CONNECT_AFTER)</literal>
2265 * </para></listitem>
2268 * <term>object_signal_after</term>
2269 * <term>object-signal-after</term>
2271 * equivalent to <literal>g_signal_connect_object (..., G_CONNECT_AFTER)</literal>
2272 * </para></listitem>
2275 * <term>swapped_signal_after</term>
2276 * <term>swapped-signal-after</term>
2278 * equivalent to <literal>g_signal_connect_data (..., NULL, G_CONNECT_SWAPPED | G_CONNECT_AFTER)</literal>
2279 * </para></listitem>
2282 * <term>swapped_object_signal_after</term>
2283 * <term>swapped-object-signal-after</term>
2285 * equivalent to <literal>g_signal_connect_object (..., G_CONNECT_SWAPPED | G_CONNECT_AFTER)</literal>
2286 * </para></listitem>
2291 * menu->toplevel = g_object_connect (g_object_new (GTK_TYPE_WINDOW,
2292 * "type", GTK_WINDOW_POPUP,
2295 * "signal::event", gtk_menu_window_event, menu,
2296 * "signal::size_request", gtk_menu_window_size_request, menu,
2297 * "signal::destroy", gtk_widget_destroyed, &menu->toplevel,
2301 * Returns: (transfer none): @object
2304 g_object_connect (gpointer _object,
2305 const gchar *signal_spec,
2308 GObject *object = _object;
2311 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
2312 g_return_val_if_fail (object->ref_count > 0, object);
2314 va_start (var_args, signal_spec);
2317 GCallback callback = va_arg (var_args, GCallback);
2318 gpointer data = va_arg (var_args, gpointer);
2320 if (strncmp (signal_spec, "signal::", 8) == 0)
2321 g_signal_connect_data (object, signal_spec + 8,
2322 callback, data, NULL,
2324 else if (strncmp (signal_spec, "object_signal::", 15) == 0 ||
2325 strncmp (signal_spec, "object-signal::", 15) == 0)
2326 g_signal_connect_object (object, signal_spec + 15,
2329 else if (strncmp (signal_spec, "swapped_signal::", 16) == 0 ||
2330 strncmp (signal_spec, "swapped-signal::", 16) == 0)
2331 g_signal_connect_data (object, signal_spec + 16,
2332 callback, data, NULL,
2334 else if (strncmp (signal_spec, "swapped_object_signal::", 23) == 0 ||
2335 strncmp (signal_spec, "swapped-object-signal::", 23) == 0)
2336 g_signal_connect_object (object, signal_spec + 23,
2339 else if (strncmp (signal_spec, "signal_after::", 14) == 0 ||
2340 strncmp (signal_spec, "signal-after::", 14) == 0)
2341 g_signal_connect_data (object, signal_spec + 14,
2342 callback, data, NULL,
2344 else if (strncmp (signal_spec, "object_signal_after::", 21) == 0 ||
2345 strncmp (signal_spec, "object-signal-after::", 21) == 0)
2346 g_signal_connect_object (object, signal_spec + 21,
2349 else if (strncmp (signal_spec, "swapped_signal_after::", 22) == 0 ||
2350 strncmp (signal_spec, "swapped-signal-after::", 22) == 0)
2351 g_signal_connect_data (object, signal_spec + 22,
2352 callback, data, NULL,
2353 G_CONNECT_SWAPPED | G_CONNECT_AFTER);
2354 else if (strncmp (signal_spec, "swapped_object_signal_after::", 29) == 0 ||
2355 strncmp (signal_spec, "swapped-object-signal-after::", 29) == 0)
2356 g_signal_connect_object (object, signal_spec + 29,
2358 G_CONNECT_SWAPPED | G_CONNECT_AFTER);
2361 g_warning ("%s: invalid signal spec \"%s\"", G_STRFUNC, signal_spec);
2364 signal_spec = va_arg (var_args, gchar*);
2372 * g_object_disconnect: (skip)
2373 * @object: a #GObject
2374 * @signal_spec: the spec for the first signal
2375 * @...: #GCallback for the first signal, followed by data for the first signal,
2376 * followed optionally by more signal spec/callback/data triples,
2379 * A convenience function to disconnect multiple signals at once.
2381 * The signal specs expected by this function have the form
2382 * "any_signal", which means to disconnect any signal with matching
2383 * callback and data, or "any_signal::signal_name", which only
2384 * disconnects the signal named "signal_name".
2387 g_object_disconnect (gpointer _object,
2388 const gchar *signal_spec,
2391 GObject *object = _object;
2394 g_return_if_fail (G_IS_OBJECT (object));
2395 g_return_if_fail (object->ref_count > 0);
2397 va_start (var_args, signal_spec);
2400 GCallback callback = va_arg (var_args, GCallback);
2401 gpointer data = va_arg (var_args, gpointer);
2402 guint sid = 0, detail = 0, mask = 0;
2404 if (strncmp (signal_spec, "any_signal::", 12) == 0 ||
2405 strncmp (signal_spec, "any-signal::", 12) == 0)
2408 mask = G_SIGNAL_MATCH_ID | G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA;
2410 else if (strcmp (signal_spec, "any_signal") == 0 ||
2411 strcmp (signal_spec, "any-signal") == 0)
2414 mask = G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA;
2418 g_warning ("%s: invalid signal spec \"%s\"", G_STRFUNC, signal_spec);
2422 if ((mask & G_SIGNAL_MATCH_ID) &&
2423 !g_signal_parse_name (signal_spec, G_OBJECT_TYPE (object), &sid, &detail, FALSE))
2424 g_warning ("%s: invalid signal name \"%s\"", G_STRFUNC, signal_spec);
2425 else if (!g_signal_handlers_disconnect_matched (object, mask | (detail ? G_SIGNAL_MATCH_DETAIL : 0),
2427 NULL, (gpointer)callback, data))
2428 g_warning ("%s: signal handler %p(%p) is not connected", G_STRFUNC, callback, data);
2429 signal_spec = va_arg (var_args, gchar*);
2440 } weak_refs[1]; /* flexible array */
2444 weak_refs_notify (gpointer data)
2446 WeakRefStack *wstack = data;
2449 for (i = 0; i < wstack->n_weak_refs; i++)
2450 wstack->weak_refs[i].notify (wstack->weak_refs[i].data, wstack->object);
2455 * g_object_weak_ref: (skip)
2456 * @object: #GObject to reference weakly
2457 * @notify: callback to invoke before the object is freed
2458 * @data: extra data to pass to notify
2460 * Adds a weak reference callback to an object. Weak references are
2461 * used for notification when an object is finalized. They are called
2462 * "weak references" because they allow you to safely hold a pointer
2463 * to an object without calling g_object_ref() (g_object_ref() adds a
2464 * strong reference, that is, forces the object to stay alive).
2467 g_object_weak_ref (GObject *object,
2471 WeakRefStack *wstack;
2474 g_return_if_fail (G_IS_OBJECT (object));
2475 g_return_if_fail (notify != NULL);
2476 g_return_if_fail (object->ref_count >= 1);
2478 G_LOCK (weak_refs_mutex);
2479 wstack = g_datalist_id_remove_no_notify (&object->qdata, quark_weak_refs);
2482 i = wstack->n_weak_refs++;
2483 wstack = g_realloc (wstack, sizeof (*wstack) + sizeof (wstack->weak_refs[0]) * i);
2487 wstack = g_renew (WeakRefStack, NULL, 1);
2488 wstack->object = object;
2489 wstack->n_weak_refs = 1;
2492 wstack->weak_refs[i].notify = notify;
2493 wstack->weak_refs[i].data = data;
2494 g_datalist_id_set_data_full (&object->qdata, quark_weak_refs, wstack, weak_refs_notify);
2495 G_UNLOCK (weak_refs_mutex);
2499 * g_object_weak_unref: (skip)
2500 * @object: #GObject to remove a weak reference from
2501 * @notify: callback to search for
2502 * @data: data to search for
2504 * Removes a weak reference callback to an object.
2507 g_object_weak_unref (GObject *object,
2511 WeakRefStack *wstack;
2512 gboolean found_one = FALSE;
2514 g_return_if_fail (G_IS_OBJECT (object));
2515 g_return_if_fail (notify != NULL);
2517 G_LOCK (weak_refs_mutex);
2518 wstack = g_datalist_id_get_data (&object->qdata, quark_weak_refs);
2523 for (i = 0; i < wstack->n_weak_refs; i++)
2524 if (wstack->weak_refs[i].notify == notify &&
2525 wstack->weak_refs[i].data == data)
2528 wstack->n_weak_refs -= 1;
2529 if (i != wstack->n_weak_refs)
2530 wstack->weak_refs[i] = wstack->weak_refs[wstack->n_weak_refs];
2535 G_UNLOCK (weak_refs_mutex);
2537 g_warning ("%s: couldn't find weak ref %p(%p)", G_STRFUNC, notify, data);
2541 * g_object_add_weak_pointer: (skip)
2542 * @object: The object that should be weak referenced.
2543 * @weak_pointer_location: (inout): The memory address of a pointer.
2545 * Adds a weak reference from weak_pointer to @object to indicate that
2546 * the pointer located at @weak_pointer_location is only valid during
2547 * the lifetime of @object. When the @object is finalized,
2548 * @weak_pointer will be set to %NULL.
2551 g_object_add_weak_pointer (GObject *object,
2552 gpointer *weak_pointer_location)
2554 g_return_if_fail (G_IS_OBJECT (object));
2555 g_return_if_fail (weak_pointer_location != NULL);
2557 g_object_weak_ref (object,
2558 (GWeakNotify) g_nullify_pointer,
2559 weak_pointer_location);
2563 * g_object_remove_weak_pointer: (skip)
2564 * @object: The object that is weak referenced.
2565 * @weak_pointer_location: (inout): The memory address of a pointer.
2567 * Removes a weak reference from @object that was previously added
2568 * using g_object_add_weak_pointer(). The @weak_pointer_location has
2569 * to match the one used with g_object_add_weak_pointer().
2572 g_object_remove_weak_pointer (GObject *object,
2573 gpointer *weak_pointer_location)
2575 g_return_if_fail (G_IS_OBJECT (object));
2576 g_return_if_fail (weak_pointer_location != NULL);
2578 g_object_weak_unref (object,
2579 (GWeakNotify) g_nullify_pointer,
2580 weak_pointer_location);
2584 object_floating_flag_handler (GObject *object,
2590 case +1: /* force floating 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 | OBJECT_FLOATING_FLAG)));
2595 return (gsize) oldvalue & OBJECT_FLOATING_FLAG;
2596 case -1: /* sink if possible */
2598 oldvalue = g_atomic_pointer_get (&object->qdata);
2599 while (!g_atomic_pointer_compare_and_exchange ((void**) &object->qdata, oldvalue,
2600 (gpointer) ((gsize) oldvalue & ~(gsize) OBJECT_FLOATING_FLAG)));
2601 return (gsize) oldvalue & OBJECT_FLOATING_FLAG;
2602 default: /* check floating */
2603 return 0 != ((gsize) g_atomic_pointer_get (&object->qdata) & OBJECT_FLOATING_FLAG);
2608 * g_object_is_floating:
2609 * @object: (type GObject.Object): a #GObject
2611 * Checks whether @object has a <link linkend="floating-ref">floating</link>
2616 * Returns: %TRUE if @object has a floating reference
2619 g_object_is_floating (gpointer _object)
2621 GObject *object = _object;
2622 g_return_val_if_fail (G_IS_OBJECT (object), FALSE);
2623 return floating_flag_handler (object, 0);
2627 * g_object_ref_sink:
2628 * @object: (type GObject.Object): a #GObject
2630 * Increase the reference count of @object, and possibly remove the
2631 * <link linkend="floating-ref">floating</link> reference, if @object
2632 * has a floating reference.
2634 * In other words, if the object is floating, then this call "assumes
2635 * ownership" of the floating reference, converting it to a normal
2636 * reference by clearing the floating flag while leaving the reference
2637 * count unchanged. If the object is not floating, then this call
2638 * adds a new normal reference increasing the reference count by one.
2642 * Returns: (type GObject.Object) (transfer none): @object
2645 g_object_ref_sink (gpointer _object)
2647 GObject *object = _object;
2648 gboolean was_floating;
2649 g_return_val_if_fail (G_IS_OBJECT (object), object);
2650 g_return_val_if_fail (object->ref_count >= 1, object);
2651 g_object_ref (object);
2652 was_floating = floating_flag_handler (object, -1);
2654 g_object_unref (object);
2659 * g_object_force_floating:
2660 * @object: a #GObject
2662 * This function is intended for #GObject implementations to re-enforce a
2663 * <link linkend="floating-ref">floating</link> object reference.
2664 * Doing this is seldom required: all
2665 * #GInitiallyUnowned<!-- -->s are created with a floating reference which
2666 * usually just needs to be sunken by calling g_object_ref_sink().
2671 g_object_force_floating (GObject *object)
2673 g_return_if_fail (G_IS_OBJECT (object));
2674 g_return_if_fail (object->ref_count >= 1);
2676 floating_flag_handler (object, +1);
2681 guint n_toggle_refs;
2683 GToggleNotify notify;
2685 } toggle_refs[1]; /* flexible array */
2689 toggle_refs_notify (GObject *object,
2690 gboolean is_last_ref)
2692 ToggleRefStack tstack, *tstackptr;
2694 G_LOCK (toggle_refs_mutex);
2695 tstackptr = g_datalist_id_get_data (&object->qdata, quark_toggle_refs);
2696 tstack = *tstackptr;
2697 G_UNLOCK (toggle_refs_mutex);
2699 /* Reentrancy here is not as tricky as it seems, because a toggle reference
2700 * will only be notified when there is exactly one of them.
2702 g_assert (tstack.n_toggle_refs == 1);
2703 tstack.toggle_refs[0].notify (tstack.toggle_refs[0].data, tstack.object, is_last_ref);
2707 * g_object_add_toggle_ref: (skip)
2708 * @object: a #GObject
2709 * @notify: a function to call when this reference is the
2710 * last reference to the object, or is no longer
2711 * the last reference.
2712 * @data: data to pass to @notify
2714 * Increases the reference count of the object by one and sets a
2715 * callback to be called when all other references to the object are
2716 * dropped, or when this is already the last reference to the object
2717 * and another reference is established.
2719 * This functionality is intended for binding @object to a proxy
2720 * object managed by another memory manager. This is done with two
2721 * paired references: the strong reference added by
2722 * g_object_add_toggle_ref() and a reverse reference to the proxy
2723 * object which is either a strong reference or weak reference.
2725 * The setup is that when there are no other references to @object,
2726 * only a weak reference is held in the reverse direction from @object
2727 * to the proxy object, but when there are other references held to
2728 * @object, a strong reference is held. The @notify callback is called
2729 * when the reference from @object to the proxy object should be
2730 * <firstterm>toggled</firstterm> from strong to weak (@is_last_ref
2731 * true) or weak to strong (@is_last_ref false).
2733 * Since a (normal) reference must be held to the object before
2734 * calling g_object_add_toggle_ref(), the initial state of the reverse
2735 * link is always strong.
2737 * Multiple toggle references may be added to the same gobject,
2738 * however if there are multiple toggle references to an object, none
2739 * of them will ever be notified until all but one are removed. For
2740 * this reason, you should only ever use a toggle reference if there
2741 * is important state in the proxy object.
2746 g_object_add_toggle_ref (GObject *object,
2747 GToggleNotify notify,
2750 ToggleRefStack *tstack;
2753 g_return_if_fail (G_IS_OBJECT (object));
2754 g_return_if_fail (notify != NULL);
2755 g_return_if_fail (object->ref_count >= 1);
2757 g_object_ref (object);
2759 G_LOCK (toggle_refs_mutex);
2760 tstack = g_datalist_id_remove_no_notify (&object->qdata, quark_toggle_refs);
2763 i = tstack->n_toggle_refs++;
2764 /* allocate i = tstate->n_toggle_refs - 1 positions beyond the 1 declared
2765 * in tstate->toggle_refs */
2766 tstack = g_realloc (tstack, sizeof (*tstack) + sizeof (tstack->toggle_refs[0]) * i);
2770 tstack = g_renew (ToggleRefStack, NULL, 1);
2771 tstack->object = object;
2772 tstack->n_toggle_refs = 1;
2776 /* Set a flag for fast lookup after adding the first toggle reference */
2777 if (tstack->n_toggle_refs == 1)
2778 g_datalist_set_flags (&object->qdata, OBJECT_HAS_TOGGLE_REF_FLAG);
2780 tstack->toggle_refs[i].notify = notify;
2781 tstack->toggle_refs[i].data = data;
2782 g_datalist_id_set_data_full (&object->qdata, quark_toggle_refs, tstack,
2783 (GDestroyNotify)g_free);
2784 G_UNLOCK (toggle_refs_mutex);
2788 * g_object_remove_toggle_ref: (skip)
2789 * @object: a #GObject
2790 * @notify: a function to call when this reference is the
2791 * last reference to the object, or is no longer
2792 * the last reference.
2793 * @data: data to pass to @notify
2795 * Removes a reference added with g_object_add_toggle_ref(). The
2796 * reference count of the object is decreased by one.
2801 g_object_remove_toggle_ref (GObject *object,
2802 GToggleNotify notify,
2805 ToggleRefStack *tstack;
2806 gboolean found_one = FALSE;
2808 g_return_if_fail (G_IS_OBJECT (object));
2809 g_return_if_fail (notify != NULL);
2811 G_LOCK (toggle_refs_mutex);
2812 tstack = g_datalist_id_get_data (&object->qdata, quark_toggle_refs);
2817 for (i = 0; i < tstack->n_toggle_refs; i++)
2818 if (tstack->toggle_refs[i].notify == notify &&
2819 tstack->toggle_refs[i].data == data)
2822 tstack->n_toggle_refs -= 1;
2823 if (i != tstack->n_toggle_refs)
2824 tstack->toggle_refs[i] = tstack->toggle_refs[tstack->n_toggle_refs];
2826 if (tstack->n_toggle_refs == 0)
2827 g_datalist_unset_flags (&object->qdata, OBJECT_HAS_TOGGLE_REF_FLAG);
2832 G_UNLOCK (toggle_refs_mutex);
2835 g_object_unref (object);
2837 g_warning ("%s: couldn't find toggle ref %p(%p)", G_STRFUNC, notify, data);
2842 * @object: (type GObject.Object): a #GObject
2844 * Increases the reference count of @object.
2846 * Returns: (type GObject.Object) (transfer none): the same @object
2849 g_object_ref (gpointer _object)
2851 GObject *object = _object;
2854 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
2855 g_return_val_if_fail (object->ref_count > 0, NULL);
2857 #ifdef G_ENABLE_DEBUG
2858 if (g_trap_object_ref == object)
2860 #endif /* G_ENABLE_DEBUG */
2863 old_val = g_atomic_int_add (&object->ref_count, 1);
2865 if (old_val == 1 && OBJECT_HAS_TOGGLE_REF (object))
2866 toggle_refs_notify (object, FALSE);
2868 TRACE (GOBJECT_OBJECT_REF(object,G_TYPE_FROM_INSTANCE(object),old_val));
2875 * @object: (type GObject.Object): a #GObject
2877 * Decreases the reference count of @object. When its reference count
2878 * drops to 0, the object is finalized (i.e. its memory is freed).
2881 g_object_unref (gpointer _object)
2883 GObject *object = _object;
2886 g_return_if_fail (G_IS_OBJECT (object));
2887 g_return_if_fail (object->ref_count > 0);
2889 #ifdef G_ENABLE_DEBUG
2890 if (g_trap_object_ref == object)
2892 #endif /* G_ENABLE_DEBUG */
2894 /* here we want to atomically do: if (ref_count>1) { ref_count--; return; } */
2895 retry_atomic_decrement1:
2896 old_ref = g_atomic_int_get (&object->ref_count);
2899 /* valid if last 2 refs are owned by this call to unref and the toggle_ref */
2900 gboolean has_toggle_ref = OBJECT_HAS_TOGGLE_REF (object);
2902 if (!g_atomic_int_compare_and_exchange ((int *)&object->ref_count, old_ref, old_ref - 1))
2903 goto retry_atomic_decrement1;
2905 TRACE (GOBJECT_OBJECT_UNREF(object,G_TYPE_FROM_INSTANCE(object),old_ref));
2907 /* if we went from 2->1 we need to notify toggle refs if any */
2908 if (old_ref == 2 && has_toggle_ref) /* The last ref being held in this case is owned by the toggle_ref */
2909 toggle_refs_notify (object, TRUE);
2913 /* we are about tp remove the last reference */
2914 TRACE (GOBJECT_OBJECT_DISPOSE(object,G_TYPE_FROM_INSTANCE(object), 1));
2915 G_OBJECT_GET_CLASS (object)->dispose (object);
2916 TRACE (GOBJECT_OBJECT_DISPOSE_END(object,G_TYPE_FROM_INSTANCE(object), 1));
2918 /* may have been re-referenced meanwhile */
2919 retry_atomic_decrement2:
2920 old_ref = g_atomic_int_get ((int *)&object->ref_count);
2923 /* valid if last 2 refs are owned by this call to unref and the toggle_ref */
2924 gboolean has_toggle_ref = OBJECT_HAS_TOGGLE_REF (object);
2926 if (!g_atomic_int_compare_and_exchange ((int *)&object->ref_count, old_ref, old_ref - 1))
2927 goto retry_atomic_decrement2;
2929 TRACE (GOBJECT_OBJECT_UNREF(object,G_TYPE_FROM_INSTANCE(object),old_ref));
2931 /* if we went from 2->1 we need to notify toggle refs if any */
2932 if (old_ref == 2 && has_toggle_ref) /* The last ref being held in this case is owned by the toggle_ref */
2933 toggle_refs_notify (object, TRUE);
2938 /* we are still in the process of taking away the last ref */
2939 g_datalist_id_set_data (&object->qdata, quark_closure_array, NULL);
2940 g_signal_handlers_destroy (object);
2941 g_datalist_id_set_data (&object->qdata, quark_weak_refs, NULL);
2943 /* decrement the last reference */
2944 old_ref = g_atomic_int_add (&object->ref_count, -1);
2946 TRACE (GOBJECT_OBJECT_UNREF(object,G_TYPE_FROM_INSTANCE(object),old_ref));
2948 /* may have been re-referenced meanwhile */
2949 if (G_LIKELY (old_ref == 1))
2951 TRACE (GOBJECT_OBJECT_FINALIZE(object,G_TYPE_FROM_INSTANCE(object)));
2952 G_OBJECT_GET_CLASS (object)->finalize (object);
2954 TRACE (GOBJECT_OBJECT_FINALIZE_END(object,G_TYPE_FROM_INSTANCE(object)));
2956 #ifdef G_ENABLE_DEBUG
2959 /* catch objects not chaining finalize handlers */
2960 G_LOCK (debug_objects);
2961 g_assert (g_hash_table_lookup (debug_objects_ht, object) == NULL);
2962 G_UNLOCK (debug_objects);
2964 #endif /* G_ENABLE_DEBUG */
2965 g_type_free_instance ((GTypeInstance*) object);
2971 * g_clear_object: (skip)
2972 * @object_ptr: a pointer to a #GObject reference
2974 * Clears a reference to a #GObject.
2976 * @object_ptr must not be %NULL.
2978 * If the reference is %NULL then this function does nothing.
2979 * Otherwise, the reference count of the object is decreased and the
2980 * pointer is set to %NULL.
2982 * This function is threadsafe and modifies the pointer atomically,
2983 * using memory barriers where needed.
2985 * A macro is also included that allows this function to be used without
2990 #undef g_clear_object
2992 g_clear_object (volatile GObject **object_ptr)
2994 gpointer *ptr = (gpointer) object_ptr;
2997 /* This is a little frustrating.
2998 * Would be nice to have an atomic exchange (with no compare).
3001 old = g_atomic_pointer_get (ptr);
3002 while G_UNLIKELY (!g_atomic_pointer_compare_and_exchange (ptr, old, NULL));
3005 g_object_unref (old);
3009 * g_object_get_qdata:
3010 * @object: The GObject to get a stored user data pointer from
3011 * @quark: A #GQuark, naming the user data pointer
3013 * This function gets back user data pointers stored via
3014 * g_object_set_qdata().
3016 * Returns: (transfer none): The user data pointer set, or %NULL
3019 g_object_get_qdata (GObject *object,
3022 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
3024 return quark ? g_datalist_id_get_data (&object->qdata, quark) : NULL;
3028 * g_object_set_qdata: (skip)
3029 * @object: The GObject to set store a user data pointer
3030 * @quark: A #GQuark, naming the user data pointer
3031 * @data: An opaque user data pointer
3033 * This sets an opaque, named pointer on an object.
3034 * The name is specified through a #GQuark (retrived e.g. via
3035 * g_quark_from_static_string()), and the pointer
3036 * can be gotten back from the @object with g_object_get_qdata()
3037 * until the @object is finalized.
3038 * Setting a previously set user data pointer, overrides (frees)
3039 * the old pointer set, using #NULL as pointer essentially
3040 * removes the data stored.
3043 g_object_set_qdata (GObject *object,
3047 g_return_if_fail (G_IS_OBJECT (object));
3048 g_return_if_fail (quark > 0);
3050 g_datalist_id_set_data (&object->qdata, quark, data);
3054 * g_object_set_qdata_full: (skip)
3055 * @object: The GObject to set store a user data pointer
3056 * @quark: A #GQuark, naming the user data pointer
3057 * @data: An opaque user data pointer
3058 * @destroy: Function to invoke with @data as argument, when @data
3061 * This function works like g_object_set_qdata(), but in addition,
3062 * a void (*destroy) (gpointer) function may be specified which is
3063 * called with @data as argument when the @object is finalized, or
3064 * the data is being overwritten by a call to g_object_set_qdata()
3065 * with the same @quark.
3068 g_object_set_qdata_full (GObject *object,
3071 GDestroyNotify destroy)
3073 g_return_if_fail (G_IS_OBJECT (object));
3074 g_return_if_fail (quark > 0);
3076 g_datalist_id_set_data_full (&object->qdata, quark, data,
3077 data ? destroy : (GDestroyNotify) NULL);
3081 * g_object_steal_qdata:
3082 * @object: The GObject to get a stored user data pointer from
3083 * @quark: A #GQuark, naming the user data pointer
3085 * This function gets back user data pointers stored via
3086 * g_object_set_qdata() and removes the @data from object
3087 * without invoking its destroy() function (if any was
3089 * Usually, calling this function is only required to update
3090 * user data pointers with a destroy notifier, for example:
3093 * object_add_to_user_list (GObject *object,
3094 * const gchar *new_string)
3096 * // the quark, naming the object data
3097 * GQuark quark_string_list = g_quark_from_static_string ("my-string-list");
3098 * // retrive the old string list
3099 * GList *list = g_object_steal_qdata (object, quark_string_list);
3101 * // prepend new string
3102 * list = g_list_prepend (list, g_strdup (new_string));
3103 * // this changed 'list', so we need to set it again
3104 * g_object_set_qdata_full (object, quark_string_list, list, free_string_list);
3107 * free_string_list (gpointer data)
3109 * GList *node, *list = data;
3111 * for (node = list; node; node = node->next)
3112 * g_free (node->data);
3113 * g_list_free (list);
3116 * Using g_object_get_qdata() in the above example, instead of
3117 * g_object_steal_qdata() would have left the destroy function set,
3118 * and thus the partial string list would have been freed upon
3119 * g_object_set_qdata_full().
3121 * Returns: (transfer full): The user data pointer set, or %NULL
3124 g_object_steal_qdata (GObject *object,
3127 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
3128 g_return_val_if_fail (quark > 0, NULL);
3130 return g_datalist_id_remove_no_notify (&object->qdata, quark);
3134 * g_object_get_data:
3135 * @object: #GObject containing the associations
3136 * @key: name of the key for that association
3138 * Gets a named field from the objects table of associations (see g_object_set_data()).
3140 * Returns: (transfer none): the data if found, or %NULL if no such data exists.
3143 g_object_get_data (GObject *object,
3146 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
3147 g_return_val_if_fail (key != NULL, NULL);
3149 return g_datalist_get_data (&object->qdata, key);
3153 * g_object_set_data:
3154 * @object: #GObject containing the associations.
3155 * @key: name of the key
3156 * @data: data to associate with that key
3158 * Each object carries around a table of associations from
3159 * strings to pointers. This function lets you set an association.
3161 * If the object already had an association with that name,
3162 * the old association will be destroyed.
3165 g_object_set_data (GObject *object,
3169 g_return_if_fail (G_IS_OBJECT (object));
3170 g_return_if_fail (key != NULL);
3172 g_datalist_id_set_data (&object->qdata, g_quark_from_string (key), data);
3176 * g_object_set_data_full: (skip)
3177 * @object: #GObject containing the associations
3178 * @key: name of the key
3179 * @data: data to associate with that key
3180 * @destroy: function to call when the association is destroyed
3182 * Like g_object_set_data() except it adds notification
3183 * for when the association is destroyed, either by setting it
3184 * to a different value or when the object is destroyed.
3186 * Note that the @destroy callback is not called if @data is %NULL.
3189 g_object_set_data_full (GObject *object,
3192 GDestroyNotify destroy)
3194 g_return_if_fail (G_IS_OBJECT (object));
3195 g_return_if_fail (key != NULL);
3197 g_datalist_id_set_data_full (&object->qdata, g_quark_from_string (key), data,
3198 data ? destroy : (GDestroyNotify) NULL);
3202 * g_object_steal_data:
3203 * @object: #GObject containing the associations
3204 * @key: name of the key
3206 * Remove a specified datum from the object's data associations,
3207 * without invoking the association's destroy handler.
3209 * Returns: (transfer full): the data if found, or %NULL if no such data exists.
3212 g_object_steal_data (GObject *object,
3217 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
3218 g_return_val_if_fail (key != NULL, NULL);
3220 quark = g_quark_try_string (key);
3222 return quark ? g_datalist_id_remove_no_notify (&object->qdata, quark) : NULL;
3226 g_value_object_init (GValue *value)
3228 value->data[0].v_pointer = NULL;
3232 g_value_object_free_value (GValue *value)
3234 if (value->data[0].v_pointer)
3235 g_object_unref (value->data[0].v_pointer);
3239 g_value_object_copy_value (const GValue *src_value,
3242 if (src_value->data[0].v_pointer)
3243 dest_value->data[0].v_pointer = g_object_ref (src_value->data[0].v_pointer);
3245 dest_value->data[0].v_pointer = NULL;
3249 g_value_object_transform_value (const GValue *src_value,
3252 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)))
3253 dest_value->data[0].v_pointer = g_object_ref (src_value->data[0].v_pointer);
3255 dest_value->data[0].v_pointer = NULL;
3259 g_value_object_peek_pointer (const GValue *value)
3261 return value->data[0].v_pointer;
3265 g_value_object_collect_value (GValue *value,
3266 guint n_collect_values,
3267 GTypeCValue *collect_values,
3268 guint collect_flags)
3270 if (collect_values[0].v_pointer)
3272 GObject *object = collect_values[0].v_pointer;
3274 if (object->g_type_instance.g_class == NULL)
3275 return g_strconcat ("invalid unclassed object pointer for value type `",
3276 G_VALUE_TYPE_NAME (value),
3279 else if (!g_value_type_compatible (G_OBJECT_TYPE (object), G_VALUE_TYPE (value)))
3280 return g_strconcat ("invalid object type `",
3281 G_OBJECT_TYPE_NAME (object),
3282 "' for value type `",
3283 G_VALUE_TYPE_NAME (value),
3286 /* never honour G_VALUE_NOCOPY_CONTENTS for ref-counted types */
3287 value->data[0].v_pointer = g_object_ref (object);
3290 value->data[0].v_pointer = NULL;
3296 g_value_object_lcopy_value (const GValue *value,
3297 guint n_collect_values,
3298 GTypeCValue *collect_values,
3299 guint collect_flags)
3301 GObject **object_p = collect_values[0].v_pointer;
3304 return g_strdup_printf ("value location for `%s' passed as NULL", G_VALUE_TYPE_NAME (value));
3306 if (!value->data[0].v_pointer)
3308 else if (collect_flags & G_VALUE_NOCOPY_CONTENTS)
3309 *object_p = value->data[0].v_pointer;
3311 *object_p = g_object_ref (value->data[0].v_pointer);
3317 * g_value_set_object:
3318 * @value: a valid #GValue of %G_TYPE_OBJECT derived type
3319 * @v_object: (type GObject.Object) (allow-none): object value to be set
3321 * Set the contents of a %G_TYPE_OBJECT derived #GValue to @v_object.
3323 * g_value_set_object() increases the reference count of @v_object
3324 * (the #GValue holds a reference to @v_object). If you do not wish
3325 * to increase the reference count of the object (i.e. you wish to
3326 * pass your current reference to the #GValue because you no longer
3327 * need it), use g_value_take_object() instead.
3329 * It is important that your #GValue holds a reference to @v_object (either its
3330 * own, or one it has taken) to ensure that the object won't be destroyed while
3331 * the #GValue still exists).
3334 g_value_set_object (GValue *value,
3339 g_return_if_fail (G_VALUE_HOLDS_OBJECT (value));
3341 old = value->data[0].v_pointer;
3345 g_return_if_fail (G_IS_OBJECT (v_object));
3346 g_return_if_fail (g_value_type_compatible (G_OBJECT_TYPE (v_object), G_VALUE_TYPE (value)));
3348 value->data[0].v_pointer = v_object;
3349 g_object_ref (value->data[0].v_pointer);
3352 value->data[0].v_pointer = NULL;
3355 g_object_unref (old);
3359 * g_value_set_object_take_ownership: (skip)
3360 * @value: a valid #GValue of %G_TYPE_OBJECT derived type
3361 * @v_object: (allow-none): object value to be set
3363 * This is an internal function introduced mainly for C marshallers.
3365 * Deprecated: 2.4: Use g_value_take_object() instead.
3368 g_value_set_object_take_ownership (GValue *value,
3371 g_value_take_object (value, v_object);
3375 * g_value_take_object: (skip)
3376 * @value: a valid #GValue of %G_TYPE_OBJECT derived type
3377 * @v_object: (allow-none): object value to be set
3379 * Sets the contents of a %G_TYPE_OBJECT derived #GValue to @v_object
3380 * and takes over the ownership of the callers reference to @v_object;
3381 * the caller doesn't have to unref it any more (i.e. the reference
3382 * count of the object is not increased).
3384 * If you want the #GValue to hold its own reference to @v_object, use
3385 * g_value_set_object() instead.
3390 g_value_take_object (GValue *value,
3393 g_return_if_fail (G_VALUE_HOLDS_OBJECT (value));
3395 if (value->data[0].v_pointer)
3397 g_object_unref (value->data[0].v_pointer);
3398 value->data[0].v_pointer = NULL;
3403 g_return_if_fail (G_IS_OBJECT (v_object));
3404 g_return_if_fail (g_value_type_compatible (G_OBJECT_TYPE (v_object), G_VALUE_TYPE (value)));
3406 value->data[0].v_pointer = v_object; /* we take over the reference count */
3411 * g_value_get_object:
3412 * @value: a valid #GValue of %G_TYPE_OBJECT derived type
3414 * Get the contents of a %G_TYPE_OBJECT derived #GValue.
3416 * Returns: (type GObject.Object) (transfer none): object contents of @value
3419 g_value_get_object (const GValue *value)
3421 g_return_val_if_fail (G_VALUE_HOLDS_OBJECT (value), NULL);
3423 return value->data[0].v_pointer;
3427 * g_value_dup_object:
3428 * @value: a valid #GValue whose type is derived from %G_TYPE_OBJECT
3430 * Get the contents of a %G_TYPE_OBJECT derived #GValue, increasing
3431 * its reference count. If the contents of the #GValue are %NULL, then
3432 * %NULL will be returned.
3434 * Returns: (type GObject.Object) (transfer full): object content of @value,
3435 * should be unreferenced when no longer needed.
3438 g_value_dup_object (const GValue *value)
3440 g_return_val_if_fail (G_VALUE_HOLDS_OBJECT (value), NULL);
3442 return value->data[0].v_pointer ? g_object_ref (value->data[0].v_pointer) : NULL;
3446 * g_signal_connect_object: (skip)
3447 * @instance: the instance to connect to.
3448 * @detailed_signal: a string of the form "signal-name::detail".
3449 * @c_handler: the #GCallback to connect.
3450 * @gobject: the object to pass as data to @c_handler.
3451 * @connect_flags: a combination of #GConnectFlags.
3453 * This is similar to g_signal_connect_data(), but uses a closure which
3454 * ensures that the @gobject stays alive during the call to @c_handler
3455 * by temporarily adding a reference count to @gobject.
3457 * Note that there is a bug in GObject that makes this function
3458 * much less useful than it might seem otherwise. Once @gobject is
3459 * disposed, the callback will no longer be called, but, the signal
3460 * handler is <emphasis>not</emphasis> currently disconnected. If the
3461 * @instance is itself being freed at the same time than this doesn't
3462 * matter, since the signal will automatically be removed, but
3463 * if @instance persists, then the signal handler will leak. You
3464 * should not remove the signal yourself because in a future versions of
3465 * GObject, the handler <emphasis>will</emphasis> automatically
3468 * It's possible to work around this problem in a way that will
3469 * continue to work with future versions of GObject by checking
3470 * that the signal handler is still connected before disconnected it:
3471 * <informalexample><programlisting>
3472 * if (g_signal_handler_is_connected (instance, id))
3473 * g_signal_handler_disconnect (instance, id);
3474 * </programlisting></informalexample>
3476 * Returns: the handler id.
3479 g_signal_connect_object (gpointer instance,
3480 const gchar *detailed_signal,
3481 GCallback c_handler,
3483 GConnectFlags connect_flags)
3485 g_return_val_if_fail (G_TYPE_CHECK_INSTANCE (instance), 0);
3486 g_return_val_if_fail (detailed_signal != NULL, 0);
3487 g_return_val_if_fail (c_handler != NULL, 0);
3493 g_return_val_if_fail (G_IS_OBJECT (gobject), 0);
3495 closure = ((connect_flags & G_CONNECT_SWAPPED) ? g_cclosure_new_object_swap : g_cclosure_new_object) (c_handler, gobject);
3497 return g_signal_connect_closure (instance, detailed_signal, closure, connect_flags & G_CONNECT_AFTER);
3500 return g_signal_connect_data (instance, detailed_signal, c_handler, NULL, NULL, connect_flags);
3506 GClosure *closures[1]; /* flexible array */
3508 /* don't change this structure without supplying an accessor for
3509 * watched closures, e.g.:
3510 * GSList* g_object_list_watched_closures (GObject *object)
3513 * g_return_val_if_fail (G_IS_OBJECT (object), NULL);
3514 * carray = g_object_get_data (object, "GObject-closure-array");
3517 * GSList *slist = NULL;
3519 * for (i = 0; i < carray->n_closures; i++)
3520 * slist = g_slist_prepend (slist, carray->closures[i]);
3528 object_remove_closure (gpointer data,
3531 GObject *object = data;
3535 G_LOCK (closure_array_mutex);
3536 carray = g_object_get_qdata (object, quark_closure_array);
3537 for (i = 0; i < carray->n_closures; i++)
3538 if (carray->closures[i] == closure)
3540 carray->n_closures--;
3541 if (i < carray->n_closures)
3542 carray->closures[i] = carray->closures[carray->n_closures];
3543 G_UNLOCK (closure_array_mutex);
3546 G_UNLOCK (closure_array_mutex);
3547 g_assert_not_reached ();
3551 destroy_closure_array (gpointer data)
3553 CArray *carray = data;
3554 GObject *object = carray->object;
3555 guint i, n = carray->n_closures;
3557 for (i = 0; i < n; i++)
3559 GClosure *closure = carray->closures[i];
3561 /* removing object_remove_closure() upfront is probably faster than
3562 * letting it fiddle with quark_closure_array which is empty anyways
3564 g_closure_remove_invalidate_notifier (closure, object, object_remove_closure);
3565 g_closure_invalidate (closure);
3571 * g_object_watch_closure:
3572 * @object: GObject restricting lifetime of @closure
3573 * @closure: GClosure to watch
3575 * This function essentially limits the life time of the @closure to
3576 * the life time of the object. That is, when the object is finalized,
3577 * the @closure is invalidated by calling g_closure_invalidate() on
3578 * it, in order to prevent invocations of the closure with a finalized
3579 * (nonexisting) object. Also, g_object_ref() and g_object_unref() are
3580 * added as marshal guards to the @closure, to ensure that an extra
3581 * reference count is held on @object during invocation of the
3582 * @closure. Usually, this function will be called on closures that
3583 * use this @object as closure data.
3586 g_object_watch_closure (GObject *object,
3592 g_return_if_fail (G_IS_OBJECT (object));
3593 g_return_if_fail (closure != NULL);
3594 g_return_if_fail (closure->is_invalid == FALSE);
3595 g_return_if_fail (closure->in_marshal == FALSE);
3596 g_return_if_fail (object->ref_count > 0); /* this doesn't work on finalizing objects */
3598 g_closure_add_invalidate_notifier (closure, object, object_remove_closure);
3599 g_closure_add_marshal_guards (closure,
3600 object, (GClosureNotify) g_object_ref,
3601 object, (GClosureNotify) g_object_unref);
3602 G_LOCK (closure_array_mutex);
3603 carray = g_datalist_id_remove_no_notify (&object->qdata, quark_closure_array);
3606 carray = g_renew (CArray, NULL, 1);
3607 carray->object = object;
3608 carray->n_closures = 1;
3613 i = carray->n_closures++;
3614 carray = g_realloc (carray, sizeof (*carray) + sizeof (carray->closures[0]) * i);
3616 carray->closures[i] = closure;
3617 g_datalist_id_set_data_full (&object->qdata, quark_closure_array, carray, destroy_closure_array);
3618 G_UNLOCK (closure_array_mutex);
3622 * g_closure_new_object:
3623 * @sizeof_closure: the size of the structure to allocate, must be at least
3624 * <literal>sizeof (GClosure)</literal>
3625 * @object: a #GObject pointer to store in the @data field of the newly
3626 * allocated #GClosure
3628 * A variant of g_closure_new_simple() which stores @object in the
3629 * @data field of the closure and calls g_object_watch_closure() on
3630 * @object and the created closure. This function is mainly useful
3631 * when implementing new types of closures.
3633 * Returns: (transfer full): a newly allocated #GClosure
3636 g_closure_new_object (guint sizeof_closure,
3641 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
3642 g_return_val_if_fail (object->ref_count > 0, NULL); /* this doesn't work on finalizing objects */
3644 closure = g_closure_new_simple (sizeof_closure, object);
3645 g_object_watch_closure (object, closure);
3651 * g_cclosure_new_object: (skip)
3652 * @callback_func: the function to invoke
3653 * @object: a #GObject pointer to pass to @callback_func
3655 * A variant of g_cclosure_new() which uses @object as @user_data and
3656 * calls g_object_watch_closure() on @object and the created
3657 * closure. This function is useful when you have a callback closely
3658 * associated with a #GObject, and want the callback to no longer run
3659 * after the object is is freed.
3661 * Returns: a new #GCClosure
3664 g_cclosure_new_object (GCallback callback_func,
3669 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
3670 g_return_val_if_fail (object->ref_count > 0, NULL); /* this doesn't work on finalizing objects */
3671 g_return_val_if_fail (callback_func != NULL, NULL);
3673 closure = g_cclosure_new (callback_func, object, NULL);
3674 g_object_watch_closure (object, closure);
3680 * g_cclosure_new_object_swap: (skip)
3681 * @callback_func: the function to invoke
3682 * @object: a #GObject pointer to pass to @callback_func
3684 * A variant of g_cclosure_new_swap() which uses @object as @user_data
3685 * and calls g_object_watch_closure() on @object and the created
3686 * closure. This function is useful when you have a callback closely
3687 * associated with a #GObject, and want the callback to no longer run
3688 * after the object is is freed.
3690 * Returns: a new #GCClosure
3693 g_cclosure_new_object_swap (GCallback callback_func,
3698 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
3699 g_return_val_if_fail (object->ref_count > 0, NULL); /* this doesn't work on finalizing objects */
3700 g_return_val_if_fail (callback_func != NULL, NULL);
3702 closure = g_cclosure_new_swap (callback_func, object, NULL);
3703 g_object_watch_closure (object, closure);
3709 g_object_compat_control (gsize what,
3715 case 1: /* floating base type */
3716 return G_TYPE_INITIALLY_UNOWNED;
3717 case 2: /* FIXME: remove this once GLib/Gtk+ break ABI again */
3718 floating_flag_handler = (guint(*)(GObject*,gint)) data;
3720 case 3: /* FIXME: remove this once GLib/Gtk+ break ABI again */
3722 *pp = floating_flag_handler;
3729 G_DEFINE_TYPE (GInitiallyUnowned, g_initially_unowned, G_TYPE_OBJECT);
3732 g_initially_unowned_init (GInitiallyUnowned *object)
3734 g_object_force_floating (object);
3738 g_initially_unowned_class_init (GInitiallyUnownedClass *klass)