1/* GObject - GLib Type, Object, Parameter and Signal Library
2 * Copyright (C) 1998-1999, 2000-2001 Tim Janik and Red Hat, Inc.
3 *
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
8 *
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
13 *
14 * You should have received a copy of the GNU Lesser General
15 * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
16 */
17#ifndef __G_OBJECT_H__
18#define __G_OBJECT_H__
19
20#if !defined (__GLIB_GOBJECT_H_INSIDE__) && !defined (GOBJECT_COMPILATION)
21#error "Only <glib-object.h> can be included directly."
22#endif
23
24#include <gobject/gtype.h>
25#include <gobject/gvalue.h>
26#include <gobject/gparam.h>
27#include <gobject/gclosure.h>
28#include <gobject/gsignal.h>
29#include <gobject/gboxed.h>
30
31G_BEGIN_DECLS
32
33/* --- type macros --- */
34/**
35 * G_TYPE_IS_OBJECT:
36 * @type: Type id to check
37 *
38 * Check if the passed in type id is a %G_TYPE_OBJECT or derived from it.
39 *
40 * Returns: %FALSE or %TRUE, indicating whether @type is a %G_TYPE_OBJECT.
41 */
42#define G_TYPE_IS_OBJECT(type) (G_TYPE_FUNDAMENTAL (type) == G_TYPE_OBJECT)
43/**
44 * G_OBJECT:
45 * @object: Object which is subject to casting.
46 *
47 * Casts a #GObject or derived pointer into a (GObject*) pointer.
48 *
49 * Depending on the current debugging level, this function may invoke
50 * certain runtime checks to identify invalid casts.
51 */
52#define G_OBJECT(object) (G_TYPE_CHECK_INSTANCE_CAST ((object), G_TYPE_OBJECT, GObject))
53/**
54 * G_OBJECT_CLASS:
55 * @class: a valid #GObjectClass
56 *
57 * Casts a derived #GObjectClass structure into a #GObjectClass structure.
58 */
59#define G_OBJECT_CLASS(class) (G_TYPE_CHECK_CLASS_CAST ((class), G_TYPE_OBJECT, GObjectClass))
60/**
61 * G_IS_OBJECT:
62 * @object: Instance to check for being a %G_TYPE_OBJECT.
63 *
64 * Checks whether a valid #GTypeInstance pointer is of type %G_TYPE_OBJECT.
65 */
66#if GLIB_VERSION_MAX_ALLOWED >= GLIB_VERSION_2_42
67#define G_IS_OBJECT(object) (G_TYPE_CHECK_INSTANCE_FUNDAMENTAL_TYPE ((object), G_TYPE_OBJECT))
68#else
69#define G_IS_OBJECT(object) (G_TYPE_CHECK_INSTANCE_TYPE ((object), G_TYPE_OBJECT))
70#endif
71/**
72 * G_IS_OBJECT_CLASS:
73 * @class: a #GObjectClass
74 *
75 * Checks whether @class "is a" valid #GObjectClass structure of type
76 * %G_TYPE_OBJECT or derived.
77 */
78#define G_IS_OBJECT_CLASS(class) (G_TYPE_CHECK_CLASS_TYPE ((class), G_TYPE_OBJECT))
79/**
80 * G_OBJECT_GET_CLASS:
81 * @object: a #GObject instance.
82 *
83 * Get the class structure associated to a #GObject instance.
84 *
85 * Returns: pointer to object class structure.
86 */
87#define G_OBJECT_GET_CLASS(object) (G_TYPE_INSTANCE_GET_CLASS ((object), G_TYPE_OBJECT, GObjectClass))
88/**
89 * G_OBJECT_TYPE:
90 * @object: Object to return the type id for.
91 *
92 * Get the type id of an object.
93 *
94 * Returns: Type id of @object.
95 */
96#define G_OBJECT_TYPE(object) (G_TYPE_FROM_INSTANCE (object))
97/**
98 * G_OBJECT_TYPE_NAME:
99 * @object: Object to return the type name for.
100 *
101 * Get the name of an object's type.
102 *
103 * Returns: Type name of @object. The string is owned by the type system and
104 * should not be freed.
105 */
106#define G_OBJECT_TYPE_NAME(object) (g_type_name (G_OBJECT_TYPE (object)))
107/**
108 * G_OBJECT_CLASS_TYPE:
109 * @class: a valid #GObjectClass
110 *
111 * Get the type id of a class structure.
112 *
113 * Returns: Type id of @class.
114 */
115#define G_OBJECT_CLASS_TYPE(class) (G_TYPE_FROM_CLASS (class))
116/**
117 * G_OBJECT_CLASS_NAME:
118 * @class: a valid #GObjectClass
119 *
120 * Return the name of a class structure's type.
121 *
122 * Returns: Type name of @class. The string is owned by the type system and
123 * should not be freed.
124 */
125#define G_OBJECT_CLASS_NAME(class) (g_type_name (G_OBJECT_CLASS_TYPE (class)))
126/**
127 * G_VALUE_HOLDS_OBJECT:
128 * @value: a valid #GValue structure
129 *
130 * Checks whether the given #GValue can hold values derived from type %G_TYPE_OBJECT.
131 *
132 * Returns: %TRUE on success.
133 */
134#define G_VALUE_HOLDS_OBJECT(value) (G_TYPE_CHECK_VALUE_TYPE ((value), G_TYPE_OBJECT))
135
136/* --- type macros --- */
137/**
138 * G_TYPE_INITIALLY_UNOWNED:
139 *
140 * The type for #GInitiallyUnowned.
141 */
142#define G_TYPE_INITIALLY_UNOWNED (g_initially_unowned_get_type())
143/**
144 * G_INITIALLY_UNOWNED:
145 * @object: Object which is subject to casting.
146 *
147 * Casts a #GInitiallyUnowned or derived pointer into a (GInitiallyUnowned*)
148 * pointer.
149 *
150 * Depending on the current debugging level, this function may invoke
151 * certain runtime checks to identify invalid casts.
152 */
153#define G_INITIALLY_UNOWNED(object) (G_TYPE_CHECK_INSTANCE_CAST ((object), G_TYPE_INITIALLY_UNOWNED, GInitiallyUnowned))
154/**
155 * G_INITIALLY_UNOWNED_CLASS:
156 * @class: a valid #GInitiallyUnownedClass
157 *
158 * Casts a derived #GInitiallyUnownedClass structure into a
159 * #GInitiallyUnownedClass structure.
160 */
161#define G_INITIALLY_UNOWNED_CLASS(class) (G_TYPE_CHECK_CLASS_CAST ((class), G_TYPE_INITIALLY_UNOWNED, GInitiallyUnownedClass))
162/**
163 * G_IS_INITIALLY_UNOWNED:
164 * @object: Instance to check for being a %G_TYPE_INITIALLY_UNOWNED.
165 *
166 * Checks whether a valid #GTypeInstance pointer is of type %G_TYPE_INITIALLY_UNOWNED.
167 */
168#define G_IS_INITIALLY_UNOWNED(object) (G_TYPE_CHECK_INSTANCE_TYPE ((object), G_TYPE_INITIALLY_UNOWNED))
169/**
170 * G_IS_INITIALLY_UNOWNED_CLASS:
171 * @class: a #GInitiallyUnownedClass
172 *
173 * Checks whether @class "is a" valid #GInitiallyUnownedClass structure of type
174 * %G_TYPE_INITIALLY_UNOWNED or derived.
175 */
176#define G_IS_INITIALLY_UNOWNED_CLASS(class) (G_TYPE_CHECK_CLASS_TYPE ((class), G_TYPE_INITIALLY_UNOWNED))
177/**
178 * G_INITIALLY_UNOWNED_GET_CLASS:
179 * @object: a #GInitiallyUnowned instance.
180 *
181 * Get the class structure associated to a #GInitiallyUnowned instance.
182 *
183 * Returns: pointer to object class structure.
184 */
185#define G_INITIALLY_UNOWNED_GET_CLASS(object) (G_TYPE_INSTANCE_GET_CLASS ((object), G_TYPE_INITIALLY_UNOWNED, GInitiallyUnownedClass))
186/* GInitiallyUnowned ia a GObject with initially floating reference count */
187
188
189/* --- typedefs & structures --- */
190typedef struct _GObject GObject;
191typedef struct _GObjectClass GObjectClass;
192typedef struct _GObject GInitiallyUnowned;
193typedef struct _GObjectClass GInitiallyUnownedClass;
194typedef struct _GObjectConstructParam GObjectConstructParam;
195/**
196 * GObjectGetPropertyFunc:
197 * @object: a #GObject
198 * @property_id: the numeric id under which the property was registered with
199 * g_object_class_install_property().
200 * @value: a #GValue to return the property value in
201 * @pspec: the #GParamSpec describing the property
202 *
203 * The type of the @get_property function of #GObjectClass.
204 */
205typedef void (*GObjectGetPropertyFunc) (GObject *object,
206 guint property_id,
207 GValue *value,
208 GParamSpec *pspec);
209/**
210 * GObjectSetPropertyFunc:
211 * @object: a #GObject
212 * @property_id: the numeric id under which the property was registered with
213 * g_object_class_install_property().
214 * @value: the new value for the property
215 * @pspec: the #GParamSpec describing the property
216 *
217 * The type of the @set_property function of #GObjectClass.
218 */
219typedef void (*GObjectSetPropertyFunc) (GObject *object,
220 guint property_id,
221 const GValue *value,
222 GParamSpec *pspec);
223/**
224 * GObjectFinalizeFunc:
225 * @object: the #GObject being finalized
226 *
227 * The type of the @finalize function of #GObjectClass.
228 */
229typedef void (*GObjectFinalizeFunc) (GObject *object);
230/**
231 * GWeakNotify:
232 * @data: data that was provided when the weak reference was established
233 * @where_the_object_was: the object being disposed
234 *
235 * A #GWeakNotify function can be added to an object as a callback that gets
236 * triggered when the object is finalized.
237 *
238 * Since the object is already being disposed when the #GWeakNotify is called,
239 * there's not much you could do with the object, apart from e.g. using its
240 * address as hash-index or the like.
241 *
242 * In particular, this means it’s invalid to call g_object_ref(),
243 * g_weak_ref_init(), g_weak_ref_set(), g_object_add_toggle_ref(),
244 * g_object_weak_ref(), g_object_add_weak_pointer() or any function which calls
245 * them on the object from this callback.
246 */
247typedef void (*GWeakNotify) (gpointer data,
248 GObject *where_the_object_was);
249/**
250 * GObject:
251 *
252 * The base object type.
253 *
254 * All the fields in the `GObject` structure are private to the implementation
255 * and should never be accessed directly.
256 *
257 * Since GLib 2.72, all #GObjects are guaranteed to be aligned to at least the
258 * alignment of the largest basic GLib type (typically this is #guint64 or
259 * #gdouble). If you need larger alignment for an element in a #GObject, you
260 * should allocate it on the heap (aligned), or arrange for your #GObject to be
261 * appropriately padded. This guarantee applies to the #GObject (or derived)
262 * struct, the #GObjectClass (or derived) struct, and any private data allocated
263 * by G_ADD_PRIVATE().
264 */
265struct _GObject
266{
267 GTypeInstance g_type_instance;
268
269 /*< private >*/
270 guint ref_count; /* (atomic) */
271 GData *qdata;
272};
273/**
274 * GObjectClass:
275 * @g_type_class: the parent class
276 * @constructor: the @constructor function is called by g_object_new () to
277 * complete the object initialization after all the construction properties are
278 * set. The first thing a @constructor implementation must do is chain up to the
279 * @constructor of the parent class. Overriding @constructor should be rarely
280 * needed, e.g. to handle construct properties, or to implement singletons.
281 * @set_property: the generic setter for all properties of this type. Should be
282 * overridden for every type with properties. If implementations of
283 * @set_property don't emit property change notification explicitly, this will
284 * be done implicitly by the type system. However, if the notify signal is
285 * emitted explicitly, the type system will not emit it a second time.
286 * @get_property: the generic getter for all properties of this type. Should be
287 * overridden for every type with properties.
288 * @dispose: the @dispose function is supposed to drop all references to other
289 * objects, but keep the instance otherwise intact, so that client method
290 * invocations still work. It may be run multiple times (due to reference
291 * loops). Before returning, @dispose should chain up to the @dispose method
292 * of the parent class.
293 * @finalize: instance finalization function, should finish the finalization of
294 * the instance begun in @dispose and chain up to the @finalize method of the
295 * parent class.
296 * @dispatch_properties_changed: emits property change notification for a bunch
297 * of properties. Overriding @dispatch_properties_changed should be rarely
298 * needed.
299 * @notify: the class closure for the notify signal
300 * @constructed: the @constructed function is called by g_object_new() as the
301 * final step of the object creation process. At the point of the call, all
302 * construction properties have been set on the object. The purpose of this
303 * call is to allow for object initialisation steps that can only be performed
304 * after construction properties have been set. @constructed implementors
305 * should chain up to the @constructed call of their parent class to allow it
306 * to complete its initialisation.
307 *
308 * The class structure for the GObject type.
309 *
310 * |[<!-- language="C" -->
311 * // Example of implementing a singleton using a constructor.
312 * static MySingleton *the_singleton = NULL;
313 *
314 * static GObject*
315 * my_singleton_constructor (GType type,
316 * guint n_construct_params,
317 * GObjectConstructParam *construct_params)
318 * {
319 * GObject *object;
320 *
321 * if (!the_singleton)
322 * {
323 * object = G_OBJECT_CLASS (parent_class)->constructor (type,
324 * n_construct_params,
325 * construct_params);
326 * the_singleton = MY_SINGLETON (object);
327 * }
328 * else
329 * object = g_object_ref (G_OBJECT (the_singleton));
330 *
331 * return object;
332 * }
333 * ]|
334 */
335struct _GObjectClass
336{
337 GTypeClass g_type_class;
338
339 /*< private >*/
340 GSList *construct_properties;
341
342 /*< public >*/
343 /* seldom overridden */
344 GObject* (*constructor) (GType type,
345 guint n_construct_properties,
346 GObjectConstructParam *construct_properties);
347 /* overridable methods */
348 void (*set_property) (GObject *object,
349 guint property_id,
350 const GValue *value,
351 GParamSpec *pspec);
352 void (*get_property) (GObject *object,
353 guint property_id,
354 GValue *value,
355 GParamSpec *pspec);
356 void (*dispose) (GObject *object);
357 void (*finalize) (GObject *object);
358 /* seldom overridden */
359 void (*dispatch_properties_changed) (GObject *object,
360 guint n_pspecs,
361 GParamSpec **pspecs);
362 /* signals */
363 void (*notify) (GObject *object,
364 GParamSpec *pspec);
365
366 /* called when done constructing */
367 void (*constructed) (GObject *object);
368
369 /*< private >*/
370 gsize flags;
371
372 /* padding */
373 gpointer pdummy[6];
374};
375
376/**
377 * GObjectConstructParam:
378 * @pspec: the #GParamSpec of the construct parameter
379 * @value: the value to set the parameter to
380 *
381 * The GObjectConstructParam struct is an auxiliary structure used to hand
382 * #GParamSpec/#GValue pairs to the @constructor of a #GObjectClass.
383 */
384struct _GObjectConstructParam
385{
386 GParamSpec *pspec;
387 GValue *value;
388};
389
390/**
391 * GInitiallyUnowned:
392 *
393 * A type for objects that have an initially floating reference.
394 *
395 * All the fields in the `GInitiallyUnowned` structure are private to the
396 * implementation and should never be accessed directly.
397 */
398/**
399 * GInitiallyUnownedClass:
400 *
401 * The class structure for the GInitiallyUnowned type.
402 */
403
404
405/* --- prototypes --- */
406GLIB_AVAILABLE_IN_ALL
407GType g_initially_unowned_get_type (void);
408GLIB_AVAILABLE_IN_ALL
409void g_object_class_install_property (GObjectClass *oclass,
410 guint property_id,
411 GParamSpec *pspec);
412GLIB_AVAILABLE_IN_ALL
413GParamSpec* g_object_class_find_property (GObjectClass *oclass,
414 const gchar *property_name);
415GLIB_AVAILABLE_IN_ALL
416GParamSpec**g_object_class_list_properties (GObjectClass *oclass,
417 guint *n_properties);
418GLIB_AVAILABLE_IN_ALL
419void g_object_class_override_property (GObjectClass *oclass,
420 guint property_id,
421 const gchar *name);
422GLIB_AVAILABLE_IN_ALL
423void g_object_class_install_properties (GObjectClass *oclass,
424 guint n_pspecs,
425 GParamSpec **pspecs);
426
427GLIB_AVAILABLE_IN_ALL
428void g_object_interface_install_property (gpointer g_iface,
429 GParamSpec *pspec);
430GLIB_AVAILABLE_IN_ALL
431GParamSpec* g_object_interface_find_property (gpointer g_iface,
432 const gchar *property_name);
433GLIB_AVAILABLE_IN_ALL
434GParamSpec**g_object_interface_list_properties (gpointer g_iface,
435 guint *n_properties_p);
436
437GLIB_AVAILABLE_IN_ALL
438GType g_object_get_type (void) G_GNUC_CONST;
439GLIB_AVAILABLE_IN_ALL
440gpointer g_object_new (GType object_type,
441 const gchar *first_property_name,
442 ...);
443GLIB_AVAILABLE_IN_2_54
444GObject* g_object_new_with_properties (GType object_type,
445 guint n_properties,
446 const char *names[],
447 const GValue values[]);
448
449G_GNUC_BEGIN_IGNORE_DEPRECATIONS
450
451GLIB_DEPRECATED_IN_2_54_FOR(g_object_new_with_properties)
452gpointer g_object_newv (GType object_type,
453 guint n_parameters,
454 GParameter *parameters);
455
456G_GNUC_END_IGNORE_DEPRECATIONS
457
458GLIB_AVAILABLE_IN_ALL
459GObject* g_object_new_valist (GType object_type,
460 const gchar *first_property_name,
461 va_list var_args);
462GLIB_AVAILABLE_IN_ALL
463void g_object_set (gpointer object,
464 const gchar *first_property_name,
465 ...) G_GNUC_NULL_TERMINATED;
466GLIB_AVAILABLE_IN_ALL
467void g_object_get (gpointer object,
468 const gchar *first_property_name,
469 ...) G_GNUC_NULL_TERMINATED;
470GLIB_AVAILABLE_IN_ALL
471gpointer g_object_connect (gpointer object,
472 const gchar *signal_spec,
473 ...) G_GNUC_NULL_TERMINATED;
474GLIB_AVAILABLE_IN_ALL
475void g_object_disconnect (gpointer object,
476 const gchar *signal_spec,
477 ...) G_GNUC_NULL_TERMINATED;
478GLIB_AVAILABLE_IN_2_54
479void g_object_setv (GObject *object,
480 guint n_properties,
481 const gchar *names[],
482 const GValue values[]);
483GLIB_AVAILABLE_IN_ALL
484void g_object_set_valist (GObject *object,
485 const gchar *first_property_name,
486 va_list var_args);
487GLIB_AVAILABLE_IN_2_54
488void g_object_getv (GObject *object,
489 guint n_properties,
490 const gchar *names[],
491 GValue values[]);
492GLIB_AVAILABLE_IN_ALL
493void g_object_get_valist (GObject *object,
494 const gchar *first_property_name,
495 va_list var_args);
496GLIB_AVAILABLE_IN_ALL
497void g_object_set_property (GObject *object,
498 const gchar *property_name,
499 const GValue *value);
500GLIB_AVAILABLE_IN_ALL
501void g_object_get_property (GObject *object,
502 const gchar *property_name,
503 GValue *value);
504GLIB_AVAILABLE_IN_ALL
505void g_object_freeze_notify (GObject *object);
506GLIB_AVAILABLE_IN_ALL
507void g_object_notify (GObject *object,
508 const gchar *property_name);
509GLIB_AVAILABLE_IN_ALL
510void g_object_notify_by_pspec (GObject *object,
511 GParamSpec *pspec);
512GLIB_AVAILABLE_IN_ALL
513void g_object_thaw_notify (GObject *object);
514GLIB_AVAILABLE_IN_ALL
515gboolean g_object_is_floating (gpointer object);
516GLIB_AVAILABLE_IN_ALL
517gpointer g_object_ref_sink (gpointer object);
518GLIB_AVAILABLE_IN_2_70
519gpointer g_object_take_ref (gpointer object);
520GLIB_AVAILABLE_IN_ALL
521gpointer g_object_ref (gpointer object);
522GLIB_AVAILABLE_IN_ALL
523void g_object_unref (gpointer object);
524GLIB_AVAILABLE_IN_ALL
525void g_object_weak_ref (GObject *object,
526 GWeakNotify notify,
527 gpointer data);
528GLIB_AVAILABLE_IN_ALL
529void g_object_weak_unref (GObject *object,
530 GWeakNotify notify,
531 gpointer data);
532GLIB_AVAILABLE_IN_ALL
533void g_object_add_weak_pointer (GObject *object,
534 gpointer *weak_pointer_location);
535GLIB_AVAILABLE_IN_ALL
536void g_object_remove_weak_pointer (GObject *object,
537 gpointer *weak_pointer_location);
538
539#if defined(glib_typeof) && GLIB_VERSION_MAX_ALLOWED >= GLIB_VERSION_2_56
540/* Make reference APIs type safe with macros */
541#define g_object_ref(Obj) ((glib_typeof (Obj)) (g_object_ref) (Obj))
542#define g_object_ref_sink(Obj) ((glib_typeof (Obj)) (g_object_ref_sink) (Obj))
543#endif
544
545/**
546 * GToggleNotify:
547 * @data: Callback data passed to g_object_add_toggle_ref()
548 * @object: The object on which g_object_add_toggle_ref() was called.
549 * @is_last_ref: %TRUE if the toggle reference is now the
550 * last reference to the object. %FALSE if the toggle
551 * reference was the last reference and there are now other
552 * references.
553 *
554 * A callback function used for notification when the state
555 * of a toggle reference changes.
556 *
557 * See also: g_object_add_toggle_ref()
558 */
559typedef void (*GToggleNotify) (gpointer data,
560 GObject *object,
561 gboolean is_last_ref);
562
563GLIB_AVAILABLE_IN_ALL
564void g_object_add_toggle_ref (GObject *object,
565 GToggleNotify notify,
566 gpointer data);
567GLIB_AVAILABLE_IN_ALL
568void g_object_remove_toggle_ref (GObject *object,
569 GToggleNotify notify,
570 gpointer data);
571
572GLIB_AVAILABLE_IN_ALL
573gpointer g_object_get_qdata (GObject *object,
574 GQuark quark);
575GLIB_AVAILABLE_IN_ALL
576void g_object_set_qdata (GObject *object,
577 GQuark quark,
578 gpointer data);
579GLIB_AVAILABLE_IN_ALL
580void g_object_set_qdata_full (GObject *object,
581 GQuark quark,
582 gpointer data,
583 GDestroyNotify destroy);
584GLIB_AVAILABLE_IN_ALL
585gpointer g_object_steal_qdata (GObject *object,
586 GQuark quark);
587
588GLIB_AVAILABLE_IN_2_34
589gpointer g_object_dup_qdata (GObject *object,
590 GQuark quark,
591 GDuplicateFunc dup_func,
592 gpointer user_data);
593GLIB_AVAILABLE_IN_2_34
594gboolean g_object_replace_qdata (GObject *object,
595 GQuark quark,
596 gpointer oldval,
597 gpointer newval,
598 GDestroyNotify destroy,
599 GDestroyNotify *old_destroy);
600
601GLIB_AVAILABLE_IN_ALL
602gpointer g_object_get_data (GObject *object,
603 const gchar *key);
604GLIB_AVAILABLE_IN_ALL
605void g_object_set_data (GObject *object,
606 const gchar *key,
607 gpointer data);
608GLIB_AVAILABLE_IN_ALL
609void g_object_set_data_full (GObject *object,
610 const gchar *key,
611 gpointer data,
612 GDestroyNotify destroy);
613GLIB_AVAILABLE_IN_ALL
614gpointer g_object_steal_data (GObject *object,
615 const gchar *key);
616
617GLIB_AVAILABLE_IN_2_34
618gpointer g_object_dup_data (GObject *object,
619 const gchar *key,
620 GDuplicateFunc dup_func,
621 gpointer user_data);
622GLIB_AVAILABLE_IN_2_34
623gboolean g_object_replace_data (GObject *object,
624 const gchar *key,
625 gpointer oldval,
626 gpointer newval,
627 GDestroyNotify destroy,
628 GDestroyNotify *old_destroy);
629
630
631GLIB_AVAILABLE_IN_ALL
632void g_object_watch_closure (GObject *object,
633 GClosure *closure);
634GLIB_AVAILABLE_IN_ALL
635GClosure* g_cclosure_new_object (GCallback callback_func,
636 GObject *object);
637GLIB_AVAILABLE_IN_ALL
638GClosure* g_cclosure_new_object_swap (GCallback callback_func,
639 GObject *object);
640GLIB_AVAILABLE_IN_ALL
641GClosure* g_closure_new_object (guint sizeof_closure,
642 GObject *object);
643GLIB_AVAILABLE_IN_ALL
644void g_value_set_object (GValue *value,
645 gpointer v_object);
646GLIB_AVAILABLE_IN_ALL
647gpointer g_value_get_object (const GValue *value);
648GLIB_AVAILABLE_IN_ALL
649gpointer g_value_dup_object (const GValue *value);
650GLIB_AVAILABLE_IN_ALL
651gulong g_signal_connect_object (gpointer instance,
652 const gchar *detailed_signal,
653 GCallback c_handler,
654 gpointer gobject,
655 GConnectFlags connect_flags);
656
657/*< protected >*/
658GLIB_AVAILABLE_IN_ALL
659void g_object_force_floating (GObject *object);
660GLIB_AVAILABLE_IN_ALL
661void g_object_run_dispose (GObject *object);
662
663
664GLIB_AVAILABLE_IN_ALL
665void g_value_take_object (GValue *value,
666 gpointer v_object);
667GLIB_DEPRECATED_FOR(g_value_take_object)
668void g_value_set_object_take_ownership (GValue *value,
669 gpointer v_object);
670
671GLIB_DEPRECATED
672gsize g_object_compat_control (gsize what,
673 gpointer data);
674
675/* --- implementation macros --- */
676#define G_OBJECT_WARN_INVALID_PSPEC(object, pname, property_id, pspec) \
677G_STMT_START { \
678 GObject *_glib__object = (GObject*) (object); \
679 GParamSpec *_glib__pspec = (GParamSpec*) (pspec); \
680 guint _glib__property_id = (property_id); \
681 g_warning ("%s:%d: invalid %s id %u for \"%s\" of type '%s' in '%s'", \
682 __FILE__, __LINE__, \
683 (pname), \
684 _glib__property_id, \
685 _glib__pspec->name, \
686 g_type_name (G_PARAM_SPEC_TYPE (_glib__pspec)), \
687 G_OBJECT_TYPE_NAME (_glib__object)); \
688} G_STMT_END
689/**
690 * G_OBJECT_WARN_INVALID_PROPERTY_ID:
691 * @object: the #GObject on which set_property() or get_property() was called
692 * @property_id: the numeric id of the property
693 * @pspec: the #GParamSpec of the property
694 *
695 * This macro should be used to emit a standard warning about unexpected
696 * properties in set_property() and get_property() implementations.
697 */
698#define G_OBJECT_WARN_INVALID_PROPERTY_ID(object, property_id, pspec) \
699 G_OBJECT_WARN_INVALID_PSPEC ((object), "property", (property_id), (pspec))
700
701GLIB_AVAILABLE_IN_ALL
702void g_clear_object (GObject **object_ptr);
703#define g_clear_object(object_ptr) g_clear_pointer ((object_ptr), g_object_unref)
704
705/**
706 * g_set_object: (skip)
707 * @object_ptr: (inout) (not optional) (nullable): a pointer to a #GObject reference
708 * @new_object: (nullable) (transfer none): a pointer to the new #GObject to
709 * assign to @object_ptr, or %NULL to clear the pointer
710 *
711 * Updates a #GObject pointer to refer to @new_object.
712 *
713 * It increments the reference count of @new_object (if non-%NULL), decrements
714 * the reference count of the current value of @object_ptr (if non-%NULL), and
715 * assigns @new_object to @object_ptr. The assignment is not atomic.
716 *
717 * @object_ptr must not be %NULL, but can point to a %NULL value.
718 *
719 * A macro is also included that allows this function to be used without
720 * pointer casts. The function itself is static inline, so its address may vary
721 * between compilation units.
722 *
723 * One convenient usage of this function is in implementing property setters:
724 * |[
725 * void
726 * foo_set_bar (Foo *foo,
727 * Bar *new_bar)
728 * {
729 * g_return_if_fail (IS_FOO (foo));
730 * g_return_if_fail (new_bar == NULL || IS_BAR (new_bar));
731 *
732 * if (g_set_object (&foo->bar, new_bar))
733 * g_object_notify (foo, "bar");
734 * }
735 * ]|
736 *
737 * Returns: %TRUE if the value of @object_ptr changed, %FALSE otherwise
738 *
739 * Since: 2.44
740 */
741static inline gboolean
742(g_set_object) (GObject **object_ptr,
743 GObject *new_object)
744{
745 GObject *old_object = *object_ptr;
746
747 /* rely on g_object_[un]ref() to check the pointers are actually GObjects;
748 * elide a (object_ptr != NULL) check because most of the time we will be
749 * operating on struct members with a constant offset, so a NULL check would
750 * not catch bugs
751 */
752
753 if (old_object == new_object)
754 return FALSE;
755
756 if (new_object != NULL)
757 g_object_ref (object: new_object);
758
759 *object_ptr = new_object;
760
761 if (old_object != NULL)
762 g_object_unref (object: old_object);
763
764 return TRUE;
765}
766
767/* We need GCC for __extension__, which we need to sort out strict aliasing of @object_ptr */
768#if defined(__GNUC__)
769
770#define g_set_object(object_ptr, new_object) \
771 (G_GNUC_EXTENSION ({ \
772 G_STATIC_ASSERT (sizeof *(object_ptr) == sizeof (new_object)); \
773 /* Only one access, please; work around type aliasing */ \
774 union { char *in; GObject **out; } _object_ptr; \
775 _object_ptr.in = (char *) (object_ptr); \
776 /* Check types match */ \
777 (void) (0 ? *(object_ptr) = (new_object), FALSE : FALSE); \
778 (g_set_object) (_object_ptr.out, (GObject *) new_object); \
779 })) \
780 GLIB_AVAILABLE_MACRO_IN_2_44
781
782#else /* if !defined(__GNUC__) */
783
784#define g_set_object(object_ptr, new_object) \
785 (/* Check types match. */ \
786 0 ? *(object_ptr) = (new_object), FALSE : \
787 (g_set_object) ((GObject **) (object_ptr), (GObject *) (new_object)) \
788 )
789
790#endif /* !defined(__GNUC__) */
791
792/**
793 * g_assert_finalize_object: (skip)
794 * @object: (transfer full) (type GObject.Object): an object
795 *
796 * Assert that @object is non-%NULL, then release one reference to it with
797 * g_object_unref() and assert that it has been finalized (i.e. that there
798 * are no more references).
799 *
800 * If assertions are disabled via `G_DISABLE_ASSERT`,
801 * this macro just calls g_object_unref() without any further checks.
802 *
803 * This macro should only be used in regression tests.
804 *
805 * Since: 2.62
806 */
807static inline void
808(g_assert_finalize_object) (GObject *object)
809{
810 gpointer weak_pointer = object;
811
812 g_assert_true (G_IS_OBJECT (weak_pointer));
813 g_object_add_weak_pointer (object, weak_pointer_location: &weak_pointer);
814 g_object_unref (object: weak_pointer);
815 g_assert_null (weak_pointer);
816}
817
818#ifdef G_DISABLE_ASSERT
819#define g_assert_finalize_object(object) g_object_unref (object)
820#else
821#define g_assert_finalize_object(object) (g_assert_finalize_object ((GObject *) object))
822#endif
823
824/**
825 * g_clear_weak_pointer: (skip)
826 * @weak_pointer_location: The memory address of a pointer
827 *
828 * Clears a weak reference to a #GObject.
829 *
830 * @weak_pointer_location must not be %NULL.
831 *
832 * If the weak reference is %NULL then this function does nothing.
833 * Otherwise, the weak reference to the object is removed for that location
834 * and the pointer is set to %NULL.
835 *
836 * A macro is also included that allows this function to be used without
837 * pointer casts. The function itself is static inline, so its address may vary
838 * between compilation units.
839 *
840 * Since: 2.56
841 */
842static inline void
843(g_clear_weak_pointer) (gpointer *weak_pointer_location)
844{
845 GObject *object = (GObject *) *weak_pointer_location;
846
847 if (object != NULL)
848 {
849 g_object_remove_weak_pointer (object, weak_pointer_location);
850 *weak_pointer_location = NULL;
851 }
852}
853
854#define g_clear_weak_pointer(weak_pointer_location) \
855 (/* Check types match. */ \
856 (g_clear_weak_pointer) ((gpointer *) (weak_pointer_location)) \
857 )
858
859/**
860 * g_set_weak_pointer: (skip)
861 * @weak_pointer_location: the memory address of a pointer
862 * @new_object: (nullable) (transfer none): a pointer to the new #GObject to
863 * assign to it, or %NULL to clear the pointer
864 *
865 * Updates a pointer to weakly refer to @new_object.
866 *
867 * It assigns @new_object to @weak_pointer_location and ensures
868 * that @weak_pointer_location will automatically be set to %NULL
869 * if @new_object gets destroyed. The assignment is not atomic.
870 * The weak reference is not thread-safe, see g_object_add_weak_pointer()
871 * for details.
872 *
873 * The @weak_pointer_location argument must not be %NULL.
874 *
875 * A macro is also included that allows this function to be used without
876 * pointer casts. The function itself is static inline, so its address may vary
877 * between compilation units.
878 *
879 * One convenient usage of this function is in implementing property setters:
880 * |[
881 * void
882 * foo_set_bar (Foo *foo,
883 * Bar *new_bar)
884 * {
885 * g_return_if_fail (IS_FOO (foo));
886 * g_return_if_fail (new_bar == NULL || IS_BAR (new_bar));
887 *
888 * if (g_set_weak_pointer (&foo->bar, new_bar))
889 * g_object_notify (foo, "bar");
890 * }
891 * ]|
892 *
893 * Returns: %TRUE if the value of @weak_pointer_location changed, %FALSE otherwise
894 *
895 * Since: 2.56
896 */
897static inline gboolean
898(g_set_weak_pointer) (gpointer *weak_pointer_location,
899 GObject *new_object)
900{
901 GObject *old_object = (GObject *) *weak_pointer_location;
902
903 /* elide a (weak_pointer_location != NULL) check because most of the time we
904 * will be operating on struct members with a constant offset, so a NULL
905 * check would not catch bugs
906 */
907
908 if (old_object == new_object)
909 return FALSE;
910
911 if (old_object != NULL)
912 g_object_remove_weak_pointer (object: old_object, weak_pointer_location);
913
914 *weak_pointer_location = new_object;
915
916 if (new_object != NULL)
917 g_object_add_weak_pointer (object: new_object, weak_pointer_location);
918
919 return TRUE;
920}
921
922#define g_set_weak_pointer(weak_pointer_location, new_object) \
923 (/* Check types match. */ \
924 0 ? *(weak_pointer_location) = (new_object), FALSE : \
925 (g_set_weak_pointer) ((gpointer *) (weak_pointer_location), (GObject *) (new_object)) \
926 )
927
928typedef struct {
929 /*<private>*/
930 union { gpointer p; } priv;
931} GWeakRef;
932
933GLIB_AVAILABLE_IN_ALL
934void g_weak_ref_init (GWeakRef *weak_ref,
935 gpointer object);
936GLIB_AVAILABLE_IN_ALL
937void g_weak_ref_clear (GWeakRef *weak_ref);
938GLIB_AVAILABLE_IN_ALL
939gpointer g_weak_ref_get (GWeakRef *weak_ref);
940GLIB_AVAILABLE_IN_ALL
941void g_weak_ref_set (GWeakRef *weak_ref,
942 gpointer object);
943
944G_END_DECLS
945
946#endif /* __G_OBJECT_H__ */
947

source code of include/glib-2.0/gobject/gobject.h