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 
31 G_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 --- */
190 typedef struct _GObject                  GObject;
191 typedef struct _GObjectClass             GObjectClass;
192 typedef struct _GObject                  GInitiallyUnowned;
193 typedef struct _GObjectClass             GInitiallyUnownedClass;
194 typedef 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  */
205 typedef 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  */
219 typedef 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  */
229 typedef 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 typedef void (*GWeakNotify)		(gpointer      data,
243 					 GObject      *where_the_object_was);
244 /**
245  * GObject:
246  *
247  * The base object type.
248  *
249  * All the fields in the `GObject` structure are private to the implementation
250  * and should never be accessed directly.
251  */
252 struct  _GObject
253 {
254   GTypeInstance  g_type_instance;
255 
256   /*< private >*/
257   guint          ref_count;  /* (atomic) */
258   GData         *qdata;
259 };
260 /**
261  * GObjectClass:
262  * @g_type_class: the parent class
263  * @constructor: the @constructor function is called by g_object_new () to
264  *  complete the object initialization after all the construction properties are
265  *  set. The first thing a @constructor implementation must do is chain up to the
266  *  @constructor of the parent class. Overriding @constructor should be rarely
267  *  needed, e.g. to handle construct properties, or to implement singletons.
268  * @set_property: the generic setter for all properties of this type. Should be
269  *  overridden for every type with properties. If implementations of
270  *  @set_property don't emit property change notification explicitly, this will
271  *  be done implicitly by the type system. However, if the notify signal is
272  *  emitted explicitly, the type system will not emit it a second time.
273  * @get_property: the generic getter for all properties of this type. Should be
274  *  overridden for every type with properties.
275  * @dispose: the @dispose function is supposed to drop all references to other
276  *  objects, but keep the instance otherwise intact, so that client method
277  *  invocations still work. It may be run multiple times (due to reference
278  *  loops). Before returning, @dispose should chain up to the @dispose method
279  *  of the parent class.
280  * @finalize: instance finalization function, should finish the finalization of
281  *  the instance begun in @dispose and chain up to the @finalize method of the
282  *  parent class.
283  * @dispatch_properties_changed: emits property change notification for a bunch
284  *  of properties. Overriding @dispatch_properties_changed should be rarely
285  *  needed.
286  * @notify: the class closure for the notify signal
287  * @constructed: the @constructed function is called by g_object_new() as the
288  *  final step of the object creation process.  At the point of the call, all
289  *  construction properties have been set on the object.  The purpose of this
290  *  call is to allow for object initialisation steps that can only be performed
291  *  after construction properties have been set.  @constructed implementors
292  *  should chain up to the @constructed call of their parent class to allow it
293  *  to complete its initialisation.
294  *
295  * The class structure for the GObject type.
296  *
297  * |[<!-- language="C" -->
298  * // Example of implementing a singleton using a constructor.
299  * static MySingleton *the_singleton = NULL;
300  *
301  * static GObject*
302  * my_singleton_constructor (GType                  type,
303  *                           guint                  n_construct_params,
304  *                           GObjectConstructParam *construct_params)
305  * {
306  *   GObject *object;
307  *
308  *   if (!the_singleton)
309  *     {
310  *       object = G_OBJECT_CLASS (parent_class)->constructor (type,
311  *                                                            n_construct_params,
312  *                                                            construct_params);
313  *       the_singleton = MY_SINGLETON (object);
314  *     }
315  *   else
316  *     object = g_object_ref (G_OBJECT (the_singleton));
317  *
318  *   return object;
319  * }
320  * ]|
321  */
322 struct  _GObjectClass
323 {
324   GTypeClass   g_type_class;
325 
326   /*< private >*/
327   GSList      *construct_properties;
328 
329   /*< public >*/
330   /* seldom overridden */
331   GObject*   (*constructor)     (GType                  type,
332                                  guint                  n_construct_properties,
333                                  GObjectConstructParam *construct_properties);
334   /* overridable methods */
335   void       (*set_property)		(GObject        *object,
336                                          guint           property_id,
337                                          const GValue   *value,
338                                          GParamSpec     *pspec);
339   void       (*get_property)		(GObject        *object,
340                                          guint           property_id,
341                                          GValue         *value,
342                                          GParamSpec     *pspec);
343   void       (*dispose)			(GObject        *object);
344   void       (*finalize)		(GObject        *object);
345   /* seldom overridden */
346   void       (*dispatch_properties_changed) (GObject      *object,
347 					     guint	   n_pspecs,
348 					     GParamSpec  **pspecs);
349   /* signals */
350   void	     (*notify)			(GObject	*object,
351 					 GParamSpec	*pspec);
352 
353   /* called when done constructing */
354   void	     (*constructed)		(GObject	*object);
355 
356   /*< private >*/
357   gsize		flags;
358 
359   /* padding */
360   gpointer	pdummy[6];
361 };
362 
363 /**
364  * GObjectConstructParam:
365  * @pspec: the #GParamSpec of the construct parameter
366  * @value: the value to set the parameter to
367  *
368  * The GObjectConstructParam struct is an auxiliary structure used to hand
369  * #GParamSpec/#GValue pairs to the @constructor of a #GObjectClass.
370  */
371 struct _GObjectConstructParam
372 {
373   GParamSpec *pspec;
374   GValue     *value;
375 };
376 
377 /**
378  * GInitiallyUnowned:
379  *
380  * A type for objects that have an initially floating reference.
381  *
382  * All the fields in the `GInitiallyUnowned` structure are private to the
383  * implementation and should never be accessed directly.
384  */
385 /**
386  * GInitiallyUnownedClass:
387  *
388  * The class structure for the GInitiallyUnowned type.
389  */
390 
391 
392 /* --- prototypes --- */
393 GLIB_AVAILABLE_IN_ALL
394 GType       g_initially_unowned_get_type      (void);
395 GLIB_AVAILABLE_IN_ALL
396 void        g_object_class_install_property   (GObjectClass   *oclass,
397 					       guint           property_id,
398 					       GParamSpec     *pspec);
399 GLIB_AVAILABLE_IN_ALL
400 GParamSpec* g_object_class_find_property      (GObjectClass   *oclass,
401 					       const gchar    *property_name);
402 GLIB_AVAILABLE_IN_ALL
403 GParamSpec**g_object_class_list_properties    (GObjectClass   *oclass,
404 					       guint	      *n_properties);
405 GLIB_AVAILABLE_IN_ALL
406 void        g_object_class_override_property  (GObjectClass   *oclass,
407 					       guint           property_id,
408 					       const gchar    *name);
409 GLIB_AVAILABLE_IN_ALL
410 void        g_object_class_install_properties (GObjectClass   *oclass,
411                                                guint           n_pspecs,
412                                                GParamSpec    **pspecs);
413 
414 GLIB_AVAILABLE_IN_ALL
415 void        g_object_interface_install_property (gpointer     g_iface,
416 						 GParamSpec  *pspec);
417 GLIB_AVAILABLE_IN_ALL
418 GParamSpec* g_object_interface_find_property    (gpointer     g_iface,
419 						 const gchar *property_name);
420 GLIB_AVAILABLE_IN_ALL
421 GParamSpec**g_object_interface_list_properties  (gpointer     g_iface,
422 						 guint       *n_properties_p);
423 
424 GLIB_AVAILABLE_IN_ALL
425 GType       g_object_get_type                 (void) G_GNUC_CONST;
426 GLIB_AVAILABLE_IN_ALL
427 gpointer    g_object_new                      (GType           object_type,
428 					       const gchar    *first_property_name,
429 					       ...);
430 GLIB_AVAILABLE_IN_2_54
431 GObject*    g_object_new_with_properties      (GType           object_type,
432                                                guint           n_properties,
433                                                const char     *names[],
434                                                const GValue    values[]);
435 
436 G_GNUC_BEGIN_IGNORE_DEPRECATIONS
437 
438 GLIB_DEPRECATED_IN_2_54_FOR(g_object_new_with_properties)
439 gpointer    g_object_newv		      (GType           object_type,
440 					       guint	       n_parameters,
441 					       GParameter     *parameters);
442 
443 G_GNUC_END_IGNORE_DEPRECATIONS
444 
445 GLIB_AVAILABLE_IN_ALL
446 GObject*    g_object_new_valist               (GType           object_type,
447 					       const gchar    *first_property_name,
448 					       va_list         var_args);
449 GLIB_AVAILABLE_IN_ALL
450 void	    g_object_set                      (gpointer	       object,
451 					       const gchar    *first_property_name,
452 					       ...) G_GNUC_NULL_TERMINATED;
453 GLIB_AVAILABLE_IN_ALL
454 void        g_object_get                      (gpointer        object,
455 					       const gchar    *first_property_name,
456 					       ...) G_GNUC_NULL_TERMINATED;
457 GLIB_AVAILABLE_IN_ALL
458 gpointer    g_object_connect                  (gpointer	       object,
459 					       const gchar    *signal_spec,
460 					       ...) G_GNUC_NULL_TERMINATED;
461 GLIB_AVAILABLE_IN_ALL
462 void	    g_object_disconnect               (gpointer	       object,
463 					       const gchar    *signal_spec,
464 					       ...) G_GNUC_NULL_TERMINATED;
465 GLIB_AVAILABLE_IN_2_54
466 void        g_object_setv                     (GObject        *object,
467                                                guint           n_properties,
468                                                const gchar    *names[],
469                                                const GValue    values[]);
470 GLIB_AVAILABLE_IN_ALL
471 void        g_object_set_valist               (GObject        *object,
472 					       const gchar    *first_property_name,
473 					       va_list         var_args);
474 GLIB_AVAILABLE_IN_2_54
475 void        g_object_getv                     (GObject        *object,
476                                                guint           n_properties,
477                                                const gchar    *names[],
478                                                GValue          values[]);
479 GLIB_AVAILABLE_IN_ALL
480 void        g_object_get_valist               (GObject        *object,
481 					       const gchar    *first_property_name,
482 					       va_list         var_args);
483 GLIB_AVAILABLE_IN_ALL
484 void        g_object_set_property             (GObject        *object,
485 					       const gchar    *property_name,
486 					       const GValue   *value);
487 GLIB_AVAILABLE_IN_ALL
488 void        g_object_get_property             (GObject        *object,
489 					       const gchar    *property_name,
490 					       GValue         *value);
491 GLIB_AVAILABLE_IN_ALL
492 void        g_object_freeze_notify            (GObject        *object);
493 GLIB_AVAILABLE_IN_ALL
494 void        g_object_notify                   (GObject        *object,
495 					       const gchar    *property_name);
496 GLIB_AVAILABLE_IN_ALL
497 void        g_object_notify_by_pspec          (GObject        *object,
498 					       GParamSpec     *pspec);
499 GLIB_AVAILABLE_IN_ALL
500 void        g_object_thaw_notify              (GObject        *object);
501 GLIB_AVAILABLE_IN_ALL
502 gboolean    g_object_is_floating    	      (gpointer        object);
503 GLIB_AVAILABLE_IN_ALL
504 gpointer    g_object_ref_sink       	      (gpointer	       object);
505 GLIB_AVAILABLE_IN_2_70
506 gpointer    g_object_take_ref                 (gpointer        object);
507 GLIB_AVAILABLE_IN_ALL
508 gpointer    g_object_ref                      (gpointer        object);
509 GLIB_AVAILABLE_IN_ALL
510 void        g_object_unref                    (gpointer        object);
511 GLIB_AVAILABLE_IN_ALL
512 void	    g_object_weak_ref		      (GObject	      *object,
513 					       GWeakNotify     notify,
514 					       gpointer	       data);
515 GLIB_AVAILABLE_IN_ALL
516 void	    g_object_weak_unref		      (GObject	      *object,
517 					       GWeakNotify     notify,
518 					       gpointer	       data);
519 GLIB_AVAILABLE_IN_ALL
520 void        g_object_add_weak_pointer         (GObject        *object,
521                                                gpointer       *weak_pointer_location);
522 GLIB_AVAILABLE_IN_ALL
523 void        g_object_remove_weak_pointer      (GObject        *object,
524                                                gpointer       *weak_pointer_location);
525 
526 #if defined(glib_typeof) && GLIB_VERSION_MAX_ALLOWED >= GLIB_VERSION_2_56
527 /* Make reference APIs type safe with macros */
528 #define g_object_ref(Obj) ((glib_typeof (Obj)) (g_object_ref) (Obj))
529 #define g_object_ref_sink(Obj) ((glib_typeof (Obj)) (g_object_ref_sink) (Obj))
530 #endif
531 
532 /**
533  * GToggleNotify:
534  * @data: Callback data passed to g_object_add_toggle_ref()
535  * @object: The object on which g_object_add_toggle_ref() was called.
536  * @is_last_ref: %TRUE if the toggle reference is now the
537  *  last reference to the object. %FALSE if the toggle
538  *  reference was the last reference and there are now other
539  *  references.
540  *
541  * A callback function used for notification when the state
542  * of a toggle reference changes.
543  *
544  * See also: g_object_add_toggle_ref()
545  */
546 typedef void (*GToggleNotify) (gpointer      data,
547 			       GObject      *object,
548 			       gboolean      is_last_ref);
549 
550 GLIB_AVAILABLE_IN_ALL
551 void g_object_add_toggle_ref    (GObject       *object,
552 				 GToggleNotify  notify,
553 				 gpointer       data);
554 GLIB_AVAILABLE_IN_ALL
555 void g_object_remove_toggle_ref (GObject       *object,
556 				 GToggleNotify  notify,
557 				 gpointer       data);
558 
559 GLIB_AVAILABLE_IN_ALL
560 gpointer    g_object_get_qdata                (GObject        *object,
561 					       GQuark          quark);
562 GLIB_AVAILABLE_IN_ALL
563 void        g_object_set_qdata                (GObject        *object,
564 					       GQuark          quark,
565 					       gpointer        data);
566 GLIB_AVAILABLE_IN_ALL
567 void        g_object_set_qdata_full           (GObject        *object,
568 					       GQuark          quark,
569 					       gpointer        data,
570 					       GDestroyNotify  destroy);
571 GLIB_AVAILABLE_IN_ALL
572 gpointer    g_object_steal_qdata              (GObject        *object,
573 					       GQuark          quark);
574 
575 GLIB_AVAILABLE_IN_2_34
576 gpointer    g_object_dup_qdata                (GObject        *object,
577                                                GQuark          quark,
578                                                GDuplicateFunc  dup_func,
579 					       gpointer         user_data);
580 GLIB_AVAILABLE_IN_2_34
581 gboolean    g_object_replace_qdata            (GObject        *object,
582                                                GQuark          quark,
583                                                gpointer        oldval,
584                                                gpointer        newval,
585                                                GDestroyNotify  destroy,
586 					       GDestroyNotify *old_destroy);
587 
588 GLIB_AVAILABLE_IN_ALL
589 gpointer    g_object_get_data                 (GObject        *object,
590 					       const gchar    *key);
591 GLIB_AVAILABLE_IN_ALL
592 void        g_object_set_data                 (GObject        *object,
593 					       const gchar    *key,
594 					       gpointer        data);
595 GLIB_AVAILABLE_IN_ALL
596 void        g_object_set_data_full            (GObject        *object,
597 					       const gchar    *key,
598 					       gpointer        data,
599 					       GDestroyNotify  destroy);
600 GLIB_AVAILABLE_IN_ALL
601 gpointer    g_object_steal_data               (GObject        *object,
602 					       const gchar    *key);
603 
604 GLIB_AVAILABLE_IN_2_34
605 gpointer    g_object_dup_data                 (GObject        *object,
606                                                const gchar    *key,
607                                                GDuplicateFunc  dup_func,
608 					       gpointer         user_data);
609 GLIB_AVAILABLE_IN_2_34
610 gboolean    g_object_replace_data             (GObject        *object,
611                                                const gchar    *key,
612                                                gpointer        oldval,
613                                                gpointer        newval,
614                                                GDestroyNotify  destroy,
615 					       GDestroyNotify *old_destroy);
616 
617 
618 GLIB_AVAILABLE_IN_ALL
619 void        g_object_watch_closure            (GObject        *object,
620 					       GClosure       *closure);
621 GLIB_AVAILABLE_IN_ALL
622 GClosure*   g_cclosure_new_object             (GCallback       callback_func,
623 					       GObject	      *object);
624 GLIB_AVAILABLE_IN_ALL
625 GClosure*   g_cclosure_new_object_swap        (GCallback       callback_func,
626 					       GObject	      *object);
627 GLIB_AVAILABLE_IN_ALL
628 GClosure*   g_closure_new_object              (guint           sizeof_closure,
629 					       GObject        *object);
630 GLIB_AVAILABLE_IN_ALL
631 void        g_value_set_object                (GValue         *value,
632 					       gpointer        v_object);
633 GLIB_AVAILABLE_IN_ALL
634 gpointer    g_value_get_object                (const GValue   *value);
635 GLIB_AVAILABLE_IN_ALL
636 gpointer    g_value_dup_object                (const GValue   *value);
637 GLIB_AVAILABLE_IN_ALL
638 gulong	    g_signal_connect_object           (gpointer	       instance,
639 					       const gchar    *detailed_signal,
640 					       GCallback       c_handler,
641 					       gpointer	       gobject,
642 					       GConnectFlags   connect_flags);
643 
644 /*< protected >*/
645 GLIB_AVAILABLE_IN_ALL
646 void        g_object_force_floating           (GObject        *object);
647 GLIB_AVAILABLE_IN_ALL
648 void        g_object_run_dispose	      (GObject	      *object);
649 
650 
651 GLIB_AVAILABLE_IN_ALL
652 void        g_value_take_object               (GValue         *value,
653 					       gpointer        v_object);
654 GLIB_DEPRECATED_FOR(g_value_take_object)
655 void        g_value_set_object_take_ownership (GValue         *value,
656                                                gpointer        v_object);
657 
658 GLIB_DEPRECATED
659 gsize	    g_object_compat_control	      (gsize	       what,
660 					       gpointer	       data);
661 
662 /* --- implementation macros --- */
663 #define G_OBJECT_WARN_INVALID_PSPEC(object, pname, property_id, pspec) \
664 G_STMT_START { \
665   GObject *_glib__object = (GObject*) (object); \
666   GParamSpec *_glib__pspec = (GParamSpec*) (pspec); \
667   guint _glib__property_id = (property_id); \
668   g_warning ("%s:%d: invalid %s id %u for \"%s\" of type '%s' in '%s'", \
669              __FILE__, __LINE__, \
670              (pname), \
671              _glib__property_id, \
672              _glib__pspec->name, \
673              g_type_name (G_PARAM_SPEC_TYPE (_glib__pspec)), \
674              G_OBJECT_TYPE_NAME (_glib__object)); \
675 } G_STMT_END
676 /**
677  * G_OBJECT_WARN_INVALID_PROPERTY_ID:
678  * @object: the #GObject on which set_property() or get_property() was called
679  * @property_id: the numeric id of the property
680  * @pspec: the #GParamSpec of the property
681  *
682  * This macro should be used to emit a standard warning about unexpected
683  * properties in set_property() and get_property() implementations.
684  */
685 #define G_OBJECT_WARN_INVALID_PROPERTY_ID(object, property_id, pspec) \
686     G_OBJECT_WARN_INVALID_PSPEC ((object), "property", (property_id), (pspec))
687 
688 GLIB_AVAILABLE_IN_ALL
689 void    g_clear_object (GObject **object_ptr);
690 #define g_clear_object(object_ptr) g_clear_pointer ((object_ptr), g_object_unref)
691 
692 /**
693  * g_set_object: (skip)
694  * @object_ptr: (inout) (not optional) (nullable): a pointer to a #GObject reference
695  * @new_object: (nullable) (transfer none): a pointer to the new #GObject to
696  *   assign to @object_ptr, or %NULL to clear the pointer
697  *
698  * Updates a #GObject pointer to refer to @new_object.
699  *
700  * It increments the reference count of @new_object (if non-%NULL), decrements
701  * the reference count of the current value of @object_ptr (if non-%NULL), and
702  * assigns @new_object to @object_ptr. The assignment is not atomic.
703  *
704  * @object_ptr must not be %NULL, but can point to a %NULL value.
705  *
706  * A macro is also included that allows this function to be used without
707  * pointer casts. The function itself is static inline, so its address may vary
708  * between compilation units.
709  *
710  * One convenient usage of this function is in implementing property setters:
711  * |[
712  *   void
713  *   foo_set_bar (Foo *foo,
714  *                Bar *new_bar)
715  *   {
716  *     g_return_if_fail (IS_FOO (foo));
717  *     g_return_if_fail (new_bar == NULL || IS_BAR (new_bar));
718  *
719  *     if (g_set_object (&foo->bar, new_bar))
720  *       g_object_notify (foo, "bar");
721  *   }
722  * ]|
723  *
724  * Returns: %TRUE if the value of @object_ptr changed, %FALSE otherwise
725  *
726  * Since: 2.44
727  */
gboolean(g_set_object)728 static inline gboolean
729 (g_set_object) (GObject **object_ptr,
730                 GObject  *new_object)
731 {
732   GObject *old_object = *object_ptr;
733 
734   /* rely on g_object_[un]ref() to check the pointers are actually GObjects;
735    * elide a (object_ptr != NULL) check because most of the time we will be
736    * operating on struct members with a constant offset, so a NULL check would
737    * not catch bugs
738    */
739 
740   if (old_object == new_object)
741     return FALSE;
742 
743   if (new_object != NULL)
744     g_object_ref (new_object);
745 
746   *object_ptr = new_object;
747 
748   if (old_object != NULL)
749     g_object_unref (old_object);
750 
751   return TRUE;
752 }
753 
754 /* We need GCC for __extension__, which we need to sort out strict aliasing of @object_ptr */
755 #if defined(__GNUC__)
756 
757 #define g_set_object(object_ptr, new_object) \
758   (G_GNUC_EXTENSION ({ \
759     G_STATIC_ASSERT (sizeof *(object_ptr) == sizeof (new_object)); \
760     /* Only one access, please; work around type aliasing */ \
761     union { char *in; GObject **out; } _object_ptr; \
762     _object_ptr.in = (char *) (object_ptr); \
763     /* Check types match */ \
764     (void) (0 ? *(object_ptr) = (new_object), FALSE : FALSE); \
765     (g_set_object) (_object_ptr.out, (GObject *) new_object); \
766   })) \
767   GLIB_AVAILABLE_MACRO_IN_2_44
768 
769 #else  /* if !defined(__GNUC__) */
770 
771 #define g_set_object(object_ptr, new_object) \
772  (/* Check types match. */ \
773   0 ? *(object_ptr) = (new_object), FALSE : \
774   (g_set_object) ((GObject **) (object_ptr), (GObject *) (new_object)) \
775  )
776 
777 #endif  /* !defined(__GNUC__) */
778 
779 /**
780  * g_assert_finalize_object: (skip)
781  * @object: (transfer full) (type GObject.Object): an object
782  *
783  * Assert that @object is non-%NULL, then release one reference to it with
784  * g_object_unref() and assert that it has been finalized (i.e. that there
785  * are no more references).
786  *
787  * If assertions are disabled via `G_DISABLE_ASSERT`,
788  * this macro just calls g_object_unref() without any further checks.
789  *
790  * This macro should only be used in regression tests.
791  *
792  * Since: 2.62
793  */
794 static inline void
795 (g_assert_finalize_object) (GObject *object)
796 {
797   gpointer weak_pointer = object;
798 
799   g_assert_true (G_IS_OBJECT (weak_pointer));
800   g_object_add_weak_pointer (object, &weak_pointer);
801   g_object_unref (weak_pointer);
802   g_assert_null (weak_pointer);
803 }
804 
805 #ifdef G_DISABLE_ASSERT
806 #define g_assert_finalize_object(object) g_object_unref (object)
807 #else
808 #define g_assert_finalize_object(object) (g_assert_finalize_object ((GObject *) object))
809 #endif
810 
811 /**
812  * g_clear_weak_pointer: (skip)
813  * @weak_pointer_location: The memory address of a pointer
814  *
815  * Clears a weak reference to a #GObject.
816  *
817  * @weak_pointer_location must not be %NULL.
818  *
819  * If the weak reference is %NULL then this function does nothing.
820  * Otherwise, the weak reference to the object is removed for that location
821  * and the pointer is set to %NULL.
822  *
823  * A macro is also included that allows this function to be used without
824  * pointer casts. The function itself is static inline, so its address may vary
825  * between compilation units.
826  *
827  * Since: 2.56
828  */
829 static inline void
830 (g_clear_weak_pointer) (gpointer *weak_pointer_location)
831 {
832   GObject *object = (GObject *) *weak_pointer_location;
833 
834   if (object != NULL)
835     {
836       g_object_remove_weak_pointer (object, weak_pointer_location);
837       *weak_pointer_location = NULL;
838     }
839 }
840 
841 #define g_clear_weak_pointer(weak_pointer_location) \
842  (/* Check types match. */ \
843   (g_clear_weak_pointer) ((gpointer *) (weak_pointer_location)) \
844  )
845 
846 /**
847  * g_set_weak_pointer: (skip)
848  * @weak_pointer_location: the memory address of a pointer
849  * @new_object: (nullable) (transfer none): a pointer to the new #GObject to
850  *   assign to it, or %NULL to clear the pointer
851  *
852  * Updates a pointer to weakly refer to @new_object.
853  *
854  * It assigns @new_object to @weak_pointer_location and ensures
855  * that @weak_pointer_location will automatically be set to %NULL
856  * if @new_object gets destroyed. The assignment is not atomic.
857  * The weak reference is not thread-safe, see g_object_add_weak_pointer()
858  * for details.
859  *
860  * The @weak_pointer_location argument must not be %NULL.
861  *
862  * A macro is also included that allows this function to be used without
863  * pointer casts. The function itself is static inline, so its address may vary
864  * between compilation units.
865  *
866  * One convenient usage of this function is in implementing property setters:
867  * |[
868  *   void
869  *   foo_set_bar (Foo *foo,
870  *                Bar *new_bar)
871  *   {
872  *     g_return_if_fail (IS_FOO (foo));
873  *     g_return_if_fail (new_bar == NULL || IS_BAR (new_bar));
874  *
875  *     if (g_set_weak_pointer (&foo->bar, new_bar))
876  *       g_object_notify (foo, "bar");
877  *   }
878  * ]|
879  *
880  * Returns: %TRUE if the value of @weak_pointer_location changed, %FALSE otherwise
881  *
882  * Since: 2.56
883  */
gboolean(g_set_weak_pointer)884 static inline gboolean
885 (g_set_weak_pointer) (gpointer *weak_pointer_location,
886                       GObject  *new_object)
887 {
888   GObject *old_object = (GObject *) *weak_pointer_location;
889 
890   /* elide a (weak_pointer_location != NULL) check because most of the time we
891    * will be operating on struct members with a constant offset, so a NULL
892    * check would not catch bugs
893    */
894 
895   if (old_object == new_object)
896     return FALSE;
897 
898   if (old_object != NULL)
899     g_object_remove_weak_pointer (old_object, weak_pointer_location);
900 
901   *weak_pointer_location = new_object;
902 
903   if (new_object != NULL)
904     g_object_add_weak_pointer (new_object, weak_pointer_location);
905 
906   return TRUE;
907 }
908 
909 #define g_set_weak_pointer(weak_pointer_location, new_object) \
910  (/* Check types match. */ \
911   0 ? *(weak_pointer_location) = (new_object), FALSE : \
912   (g_set_weak_pointer) ((gpointer *) (weak_pointer_location), (GObject *) (new_object)) \
913  )
914 
915 typedef struct {
916     /*<private>*/
917     union { gpointer p; } priv;
918 } GWeakRef;
919 
920 GLIB_AVAILABLE_IN_ALL
921 void     g_weak_ref_init       (GWeakRef *weak_ref,
922                                 gpointer  object);
923 GLIB_AVAILABLE_IN_ALL
924 void     g_weak_ref_clear      (GWeakRef *weak_ref);
925 GLIB_AVAILABLE_IN_ALL
926 gpointer g_weak_ref_get        (GWeakRef *weak_ref);
927 GLIB_AVAILABLE_IN_ALL
928 void     g_weak_ref_set        (GWeakRef *weak_ref,
929                                 gpointer  object);
930 
931 G_END_DECLS
932 
933 #endif /* __G_OBJECT_H__ */
934