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 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, write to the
16 * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
17 * Boston, MA 02111-1307, USA.
18 */
19
20 /*
21 * MT safe with regards to reference counting.
22 */
23
24 #include "config.h"
25
26 #include <string.h>
27 #include <signal.h>
28
29 #include "glib/gdatasetprivate.h"
30
31 #include "gobject.h"
32 #include "gvaluecollector.h"
33 #include "gsignal.h"
34 #include "gparamspecs.h"
35 #include "gvaluetypes.h"
36 #include "gobjectalias.h"
37
38 /* This should be included after gobjectalias.h (or pltcheck.sh will fail) */
39 #include "gobjectnotifyqueue.c"
40
41
42 /**
43 * SECTION:objects
44 * @short_description: The base object type
45 * @see_also: #GParamSpecObject, g_param_spec_object()
46 * @title: The Base Object Type
47 *
48 * GObject is the fundamental type providing the common attributes and
49 * methods for all object types in GTK+, Pango and other libraries
50 * based on GObject. The GObject class provides methods for object
51 * construction and destruction, property access methods, and signal
52 * support. Signals are described in detail in <xref
53 * linkend="gobject-Signals"/>.
54 *
55 * <para id="floating-ref">
56 * #GInitiallyUnowned is derived from #GObject. The only difference between
57 * the two is that the initial reference of a #GInitiallyUnowned is flagged
58 * as a <firstterm>floating</firstterm> reference.
59 * This means that it is not specifically claimed to be "owned" by
60 * any code portion. The main motivation for providing floating references is
61 * C convenience. In particular, it allows code to be written as:
62 * |[
63 * container = create_container();
64 * container_add_child (container, create_child());
65 * ]|
66 * If <function>container_add_child()</function> will g_object_ref_sink() the
67 * passed in child, no reference of the newly created child is leaked.
68 * Without floating references, <function>container_add_child()</function>
69 * can only g_object_ref() the new child, so to implement this code without
70 * reference leaks, it would have to be written as:
71 * |[
72 * Child *child;
73 * container = create_container();
74 * child = create_child();
75 * container_add_child (container, child);
76 * g_object_unref (child);
77 * ]|
78 * The floating reference can be converted into
79 * an ordinary reference by calling g_object_ref_sink().
80 * For already sunken objects (objects that don't have a floating reference
81 * anymore), g_object_ref_sink() is equivalent to g_object_ref() and returns
82 * a new reference.
83 * Since floating references are useful almost exclusively for C convenience,
84 * language bindings that provide automated reference and memory ownership
85 * maintenance (such as smart pointers or garbage collection) therefore don't
86 * need to expose floating references in their API.
87 * </para>
88 *
89 * Some object implementations may need to save an objects floating state
90 * across certain code portions (an example is #GtkMenu), to achive this, the
91 * following sequence can be used:
92 *
93 * |[
94 * // save floating state
95 * gboolean was_floating = g_object_is_floating (object);
96 * g_object_ref_sink (object);
97 * // protected code portion
98 * ...;
99 * // restore floating state
100 * if (was_floating)
101 * g_object_force_floating (object);
102 * g_obejct_unref (object); // release previously acquired reference
103 * ]|
104 */
105
106
107 /* --- macros --- */
108 #define PARAM_SPEC_PARAM_ID(pspec) ((pspec)->param_id)
109 #define PARAM_SPEC_SET_PARAM_ID(pspec, id) ((pspec)->param_id = (id))
110
111 #define OBJECT_HAS_TOGGLE_REF_FLAG 0x1
112 #define OBJECT_HAS_TOGGLE_REF(object) \
113 ((G_DATALIST_GET_FLAGS (&(object)->qdata) & OBJECT_HAS_TOGGLE_REF_FLAG) != 0)
114 #define OBJECT_FLOATING_FLAG 0x2
115
116
117 /* --- signals --- */
118 enum {
119 NOTIFY,
120 LAST_SIGNAL
121 };
122
123
124 /* --- properties --- */
125 enum {
126 PROP_NONE
127 };
128
129
130 /* --- prototypes --- */
131 static void g_object_base_class_init (GObjectClass *class);
132 static void g_object_base_class_finalize (GObjectClass *class);
133 static void g_object_do_class_init (GObjectClass *class);
134 static void g_object_init (GObject *object);
135 static GObject* g_object_constructor (GType type,
136 guint n_construct_properties,
137 GObjectConstructParam *construct_params);
138 static void g_object_real_dispose (GObject *object);
139 static void g_object_finalize (GObject *object);
140 static void g_object_do_set_property (GObject *object,
141 guint property_id,
142 const GValue *value,
143 GParamSpec *pspec);
144 static void g_object_do_get_property (GObject *object,
145 guint property_id,
146 GValue *value,
147 GParamSpec *pspec);
148 static void g_value_object_init (GValue *value);
149 static void g_value_object_free_value (GValue *value);
150 static void g_value_object_copy_value (const GValue *src_value,
151 GValue *dest_value);
152 static void g_value_object_transform_value (const GValue *src_value,
153 GValue *dest_value);
154 static gpointer g_value_object_peek_pointer (const GValue *value);
155 static gchar* g_value_object_collect_value (GValue *value,
156 guint n_collect_values,
157 GTypeCValue *collect_values,
158 guint collect_flags);
159 static gchar* g_value_object_lcopy_value (const GValue *value,
160 guint n_collect_values,
161 GTypeCValue *collect_values,
162 guint collect_flags);
163 static void g_object_dispatch_properties_changed (GObject *object,
164 guint n_pspecs,
165 GParamSpec **pspecs);
166 static inline void object_get_property (GObject *object,
167 GParamSpec *pspec,
168 GValue *value);
169 static inline void object_set_property (GObject *object,
170 GParamSpec *pspec,
171 const GValue *value,
172 GObjectNotifyQueue *nqueue);
173 static guint object_floating_flag_handler (GObject *object,
174 gint job);
175
176 static void object_interface_check_properties (gpointer func_data,
177 gpointer g_iface);
178
179
180 /* --- variables --- */
181 static GQuark quark_closure_array = 0;
182 static GQuark quark_weak_refs = 0;
183 static GQuark quark_toggle_refs = 0;
184 static GParamSpecPool *pspec_pool = NULL;
185 static GObjectNotifyContext property_notify_context = { 0, };
186 static gulong gobject_signals[LAST_SIGNAL] = { 0, };
187 static guint (*floating_flag_handler) (GObject*, gint) = object_floating_flag_handler;
188 G_LOCK_DEFINE_STATIC (construction_mutex);
189 static GSList *construction_objects = NULL;
190
191 /* --- functions --- */
192 #ifdef G_ENABLE_DEBUG
193 #define IF_DEBUG(debug_type) if (_g_type_debug_flags & G_TYPE_DEBUG_ ## debug_type)
194 G_LOCK_DEFINE_STATIC (debug_objects);
195 static volatile GObject *g_trap_object_ref = NULL;
196 static guint debug_objects_count = 0;
197 static GHashTable *debug_objects_ht = NULL;
198
199 static void
debug_objects_foreach(gpointer key,gpointer value,gpointer user_data)200 debug_objects_foreach (gpointer key,
201 gpointer value,
202 gpointer user_data)
203 {
204 GObject *object = value;
205
206 g_message ("[%p] stale %s\tref_count=%u",
207 object,
208 G_OBJECT_TYPE_NAME (object),
209 object->ref_count);
210 }
211
212 static void
debug_objects_atexit(void)213 debug_objects_atexit (void)
214 {
215 IF_DEBUG (OBJECTS)
216 {
217 G_LOCK (debug_objects);
218 g_message ("stale GObjects: %u", debug_objects_count);
219 g_hash_table_foreach (debug_objects_ht, debug_objects_foreach, NULL);
220 G_UNLOCK (debug_objects);
221 }
222 }
223 #endif /* G_ENABLE_DEBUG */
224
225 void
g_object_type_init(void)226 g_object_type_init (void)
227 {
228 static gboolean initialized = FALSE;
229 static const GTypeFundamentalInfo finfo = {
230 G_TYPE_FLAG_CLASSED | G_TYPE_FLAG_INSTANTIATABLE | G_TYPE_FLAG_DERIVABLE | G_TYPE_FLAG_DEEP_DERIVABLE,
231 };
232 static GTypeInfo info = {
233 sizeof (GObjectClass),
234 (GBaseInitFunc) g_object_base_class_init,
235 (GBaseFinalizeFunc) g_object_base_class_finalize,
236 (GClassInitFunc) g_object_do_class_init,
237 NULL /* class_destroy */,
238 NULL /* class_data */,
239 sizeof (GObject),
240 0 /* n_preallocs */,
241 (GInstanceInitFunc) g_object_init,
242 NULL, /* value_table */
243 };
244 static const GTypeValueTable value_table = {
245 g_value_object_init, /* value_init */
246 g_value_object_free_value, /* value_free */
247 g_value_object_copy_value, /* value_copy */
248 g_value_object_peek_pointer, /* value_peek_pointer */
249 "p", /* collect_format */
250 g_value_object_collect_value, /* collect_value */
251 "p", /* lcopy_format */
252 g_value_object_lcopy_value, /* lcopy_value */
253 };
254 GType type;
255
256 g_return_if_fail (initialized == FALSE);
257 initialized = TRUE;
258
259 /* G_TYPE_OBJECT
260 */
261 info.value_table = &value_table;
262 type = g_type_register_fundamental (G_TYPE_OBJECT, g_intern_static_string ("GObject"), &info, &finfo, 0);
263 g_assert (type == G_TYPE_OBJECT);
264 g_value_register_transform_func (G_TYPE_OBJECT, G_TYPE_OBJECT, g_value_object_transform_value);
265
266 #ifdef G_ENABLE_DEBUG
267 IF_DEBUG (OBJECTS)
268 {
269 debug_objects_ht = g_hash_table_new (g_direct_hash, NULL);
270 g_atexit (debug_objects_atexit);
271 }
272 #endif /* G_ENABLE_DEBUG */
273 }
274
275 static void
g_object_base_class_init(GObjectClass * class)276 g_object_base_class_init (GObjectClass *class)
277 {
278 GObjectClass *pclass = g_type_class_peek_parent (class);
279
280 /* reset instance specific fields and methods that don't get inherited */
281 class->construct_properties = pclass ? g_slist_copy (pclass->construct_properties) : NULL;
282 class->get_property = NULL;
283 class->set_property = NULL;
284 }
285
286 static void
g_object_base_class_finalize(GObjectClass * class)287 g_object_base_class_finalize (GObjectClass *class)
288 {
289 GList *list, *node;
290
291 _g_signals_destroy (G_OBJECT_CLASS_TYPE (class));
292
293 g_slist_free (class->construct_properties);
294 class->construct_properties = NULL;
295 list = g_param_spec_pool_list_owned (pspec_pool, G_OBJECT_CLASS_TYPE (class));
296 for (node = list; node; node = node->next)
297 {
298 GParamSpec *pspec = node->data;
299
300 g_param_spec_pool_remove (pspec_pool, pspec);
301 PARAM_SPEC_SET_PARAM_ID (pspec, 0);
302 g_param_spec_unref (pspec);
303 }
304 g_list_free (list);
305 }
306
307 static void
g_object_notify_dispatcher(GObject * object,guint n_pspecs,GParamSpec ** pspecs)308 g_object_notify_dispatcher (GObject *object,
309 guint n_pspecs,
310 GParamSpec **pspecs)
311 {
312 G_OBJECT_GET_CLASS (object)->dispatch_properties_changed (object, n_pspecs, pspecs);
313 }
314
315 static void
g_object_do_class_init(GObjectClass * class)316 g_object_do_class_init (GObjectClass *class)
317 {
318 /* read the comment about typedef struct CArray; on why not to change this quark */
319 quark_closure_array = g_quark_from_static_string ("GObject-closure-array");
320
321 quark_weak_refs = g_quark_from_static_string ("GObject-weak-references");
322 quark_toggle_refs = g_quark_from_static_string ("GObject-toggle-references");
323 pspec_pool = g_param_spec_pool_new (TRUE);
324 property_notify_context.quark_notify_queue = g_quark_from_static_string ("GObject-notify-queue");
325 property_notify_context.dispatcher = g_object_notify_dispatcher;
326
327 class->constructor = g_object_constructor;
328 class->set_property = g_object_do_set_property;
329 class->get_property = g_object_do_get_property;
330 class->dispose = g_object_real_dispose;
331 class->finalize = g_object_finalize;
332 class->dispatch_properties_changed = g_object_dispatch_properties_changed;
333 class->notify = NULL;
334
335 /**
336 * GObject::notify:
337 * @gobject: the object which received the signal.
338 * @pspec: the #GParamSpec of the property which changed.
339 *
340 * The notify signal is emitted on an object when one of its
341 * properties has been changed. Note that getting this signal
342 * doesn't guarantee that the value of the property has actually
343 * changed, it may also be emitted when the setter for the property
344 * is called to reinstate the previous value.
345 *
346 * This signal is typically used to obtain change notification for a
347 * single property, by specifying the property name as a detail in the
348 * g_signal_connect() call, like this:
349 * |[
350 * g_signal_connect (text_view->buffer, "notify::paste-target-list",
351 * G_CALLBACK (gtk_text_view_target_list_notify),
352 * text_view)
353 * ]|
354 * It is important to note that you must use
355 * <link linkend="canonical-parameter-name">canonical</link> parameter names as
356 * detail strings for the notify signal.
357 */
358 gobject_signals[NOTIFY] =
359 g_signal_new (g_intern_static_string ("notify"),
360 G_TYPE_FROM_CLASS (class),
361 G_SIGNAL_RUN_FIRST | G_SIGNAL_NO_RECURSE | G_SIGNAL_DETAILED | G_SIGNAL_NO_HOOKS | G_SIGNAL_ACTION,
362 G_STRUCT_OFFSET (GObjectClass, notify),
363 NULL, NULL,
364 g_cclosure_marshal_VOID__PARAM,
365 G_TYPE_NONE,
366 1, G_TYPE_PARAM);
367
368 /* Install a check function that we'll use to verify that classes that
369 * implement an interface implement all properties for that interface
370 */
371 g_type_add_interface_check (NULL, object_interface_check_properties);
372 }
373
374 static void
install_property_internal(GType g_type,guint property_id,GParamSpec * pspec)375 install_property_internal (GType g_type,
376 guint property_id,
377 GParamSpec *pspec)
378 {
379 if (g_param_spec_pool_lookup (pspec_pool, pspec->name, g_type, FALSE))
380 {
381 g_warning ("When installing property: type `%s' already has a property named `%s'",
382 g_type_name (g_type),
383 pspec->name);
384 return;
385 }
386
387 g_param_spec_ref (pspec);
388 g_param_spec_sink (pspec);
389 PARAM_SPEC_SET_PARAM_ID (pspec, property_id);
390 g_param_spec_pool_insert (pspec_pool, pspec, g_type);
391 }
392
393 /**
394 * g_object_class_install_property:
395 * @oclass: a #GObjectClass
396 * @property_id: the id for the new property
397 * @pspec: the #GParamSpec for the new property
398 *
399 * Installs a new property. This is usually done in the class initializer.
400 *
401 * Note that it is possible to redefine a property in a derived class,
402 * by installing a property with the same name. This can be useful at times,
403 * e.g. to change the range of allowed values or the default value.
404 */
405 void
g_object_class_install_property(GObjectClass * class,guint property_id,GParamSpec * pspec)406 g_object_class_install_property (GObjectClass *class,
407 guint property_id,
408 GParamSpec *pspec)
409 {
410 g_return_if_fail (G_IS_OBJECT_CLASS (class));
411 g_return_if_fail (G_IS_PARAM_SPEC (pspec));
412 if (pspec->flags & G_PARAM_WRITABLE)
413 g_return_if_fail (class->set_property != NULL);
414 if (pspec->flags & G_PARAM_READABLE)
415 g_return_if_fail (class->get_property != NULL);
416 g_return_if_fail (property_id > 0);
417 g_return_if_fail (PARAM_SPEC_PARAM_ID (pspec) == 0); /* paranoid */
418 if (pspec->flags & G_PARAM_CONSTRUCT)
419 g_return_if_fail ((pspec->flags & G_PARAM_CONSTRUCT_ONLY) == 0);
420 if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))
421 g_return_if_fail (pspec->flags & G_PARAM_WRITABLE);
422
423 install_property_internal (G_OBJECT_CLASS_TYPE (class), property_id, pspec);
424
425 if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))
426 class->construct_properties = g_slist_prepend (class->construct_properties, pspec);
427
428 /* for property overrides of construct poperties, we have to get rid
429 * of the overidden inherited construct property
430 */
431 pspec = g_param_spec_pool_lookup (pspec_pool, pspec->name, g_type_parent (G_OBJECT_CLASS_TYPE (class)), TRUE);
432 if (pspec && pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))
433 class->construct_properties = g_slist_remove (class->construct_properties, pspec);
434 }
435
436 /**
437 * g_object_interface_install_property:
438 * @g_iface: any interface vtable for the interface, or the default
439 * vtable for the interface.
440 * @pspec: the #GParamSpec for the new property
441 *
442 * Add a property to an interface; this is only useful for interfaces
443 * that are added to GObject-derived types. Adding a property to an
444 * interface forces all objects classes with that interface to have a
445 * compatible property. The compatible property could be a newly
446 * created #GParamSpec, but normally
447 * g_object_class_override_property() will be used so that the object
448 * class only needs to provide an implementation and inherits the
449 * property description, default value, bounds, and so forth from the
450 * interface property.
451 *
452 * This function is meant to be called from the interface's default
453 * vtable initialization function (the @class_init member of
454 * #GTypeInfo.) It must not be called after after @class_init has
455 * been called for any object types implementing this interface.
456 *
457 * Since: 2.4
458 */
459 void
g_object_interface_install_property(gpointer g_iface,GParamSpec * pspec)460 g_object_interface_install_property (gpointer g_iface,
461 GParamSpec *pspec)
462 {
463 GTypeInterface *iface_class = g_iface;
464
465 g_return_if_fail (G_TYPE_IS_INTERFACE (iface_class->g_type));
466 g_return_if_fail (G_IS_PARAM_SPEC (pspec));
467 g_return_if_fail (!G_IS_PARAM_SPEC_OVERRIDE (pspec)); /* paranoid */
468 g_return_if_fail (PARAM_SPEC_PARAM_ID (pspec) == 0); /* paranoid */
469
470 install_property_internal (iface_class->g_type, 0, pspec);
471 }
472
473 /**
474 * g_object_class_find_property:
475 * @oclass: a #GObjectClass
476 * @property_name: the name of the property to look up
477 *
478 * Looks up the #GParamSpec for a property of a class.
479 *
480 * Returns: the #GParamSpec for the property, or %NULL if the class
481 * doesn't have a property of that name
482 */
483 GParamSpec*
g_object_class_find_property(GObjectClass * class,const gchar * property_name)484 g_object_class_find_property (GObjectClass *class,
485 const gchar *property_name)
486 {
487 GParamSpec *pspec;
488 GParamSpec *redirect;
489
490 g_return_val_if_fail (G_IS_OBJECT_CLASS (class), NULL);
491 g_return_val_if_fail (property_name != NULL, NULL);
492
493 pspec = g_param_spec_pool_lookup (pspec_pool,
494 property_name,
495 G_OBJECT_CLASS_TYPE (class),
496 TRUE);
497 if (pspec)
498 {
499 redirect = g_param_spec_get_redirect_target (pspec);
500 if (redirect)
501 return redirect;
502 else
503 return pspec;
504 }
505 else
506 return NULL;
507 }
508
509 /**
510 * g_object_interface_find_property:
511 * @g_iface: any interface vtable for the interface, or the default
512 * vtable for the interface
513 * @property_name: name of a property to lookup.
514 *
515 * Find the #GParamSpec with the given name for an
516 * interface. Generally, the interface vtable passed in as @g_iface
517 * will be the default vtable from g_type_default_interface_ref(), or,
518 * if you know the interface has already been loaded,
519 * g_type_default_interface_peek().
520 *
521 * Since: 2.4
522 *
523 * Returns: the #GParamSpec for the property of the interface with the
524 * name @property_name, or %NULL if no such property exists.
525 */
526 GParamSpec*
g_object_interface_find_property(gpointer g_iface,const gchar * property_name)527 g_object_interface_find_property (gpointer g_iface,
528 const gchar *property_name)
529 {
530 GTypeInterface *iface_class = g_iface;
531
532 g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface_class->g_type), NULL);
533 g_return_val_if_fail (property_name != NULL, NULL);
534
535 return g_param_spec_pool_lookup (pspec_pool,
536 property_name,
537 iface_class->g_type,
538 FALSE);
539 }
540
541 /**
542 * g_object_class_override_property:
543 * @oclass: a #GObjectClass
544 * @property_id: the new property ID
545 * @name: the name of a property registered in a parent class or
546 * in an interface of this class.
547 *
548 * Registers @property_id as referring to a property with the
549 * name @name in a parent class or in an interface implemented
550 * by @oclass. This allows this class to <firstterm>override</firstterm>
551 * a property implementation in a parent class or to provide
552 * the implementation of a property from an interface.
553 *
554 * <note>
555 * Internally, overriding is implemented by creating a property of type
556 * #GParamSpecOverride; generally operations that query the properties of
557 * the object class, such as g_object_class_find_property() or
558 * g_object_class_list_properties() will return the overridden
559 * property. However, in one case, the @construct_properties argument of
560 * the @constructor virtual function, the #GParamSpecOverride is passed
561 * instead, so that the @param_id field of the #GParamSpec will be
562 * correct. For virtually all uses, this makes no difference. If you
563 * need to get the overridden property, you can call
564 * g_param_spec_get_redirect_target().
565 * </note>
566 *
567 * Since: 2.4
568 */
569 void
g_object_class_override_property(GObjectClass * oclass,guint property_id,const gchar * name)570 g_object_class_override_property (GObjectClass *oclass,
571 guint property_id,
572 const gchar *name)
573 {
574 GParamSpec *overridden = NULL;
575 GParamSpec *new;
576 GType parent_type;
577
578 g_return_if_fail (G_IS_OBJECT_CLASS (oclass));
579 g_return_if_fail (property_id > 0);
580 g_return_if_fail (name != NULL);
581
582 /* Find the overridden property; first check parent types
583 */
584 parent_type = g_type_parent (G_OBJECT_CLASS_TYPE (oclass));
585 if (parent_type != G_TYPE_NONE)
586 overridden = g_param_spec_pool_lookup (pspec_pool,
587 name,
588 parent_type,
589 TRUE);
590 if (!overridden)
591 {
592 GType *ifaces;
593 guint n_ifaces;
594
595 /* Now check interfaces
596 */
597 ifaces = g_type_interfaces (G_OBJECT_CLASS_TYPE (oclass), &n_ifaces);
598 while (n_ifaces-- && !overridden)
599 {
600 overridden = g_param_spec_pool_lookup (pspec_pool,
601 name,
602 ifaces[n_ifaces],
603 FALSE);
604 }
605
606 g_free (ifaces);
607 }
608
609 if (!overridden)
610 {
611 g_warning ("%s: Can't find property to override for '%s::%s'",
612 G_STRFUNC, G_OBJECT_CLASS_NAME (oclass), name);
613 return;
614 }
615
616 new = g_param_spec_override (name, overridden);
617 g_object_class_install_property (oclass, property_id, new);
618 }
619
620 /**
621 * g_object_class_list_properties:
622 * @oclass: a #GObjectClass
623 * @n_properties: return location for the length of the returned array
624 *
625 * Get an array of #GParamSpec* for all properties of a class.
626 *
627 * Returns: an array of #GParamSpec* which should be freed after use
628 */
629 GParamSpec** /* free result */
g_object_class_list_properties(GObjectClass * class,guint * n_properties_p)630 g_object_class_list_properties (GObjectClass *class,
631 guint *n_properties_p)
632 {
633 GParamSpec **pspecs;
634 guint n;
635
636 g_return_val_if_fail (G_IS_OBJECT_CLASS (class), NULL);
637
638 pspecs = g_param_spec_pool_list (pspec_pool,
639 G_OBJECT_CLASS_TYPE (class),
640 &n);
641 if (n_properties_p)
642 *n_properties_p = n;
643
644 return pspecs;
645 }
646
647 /**
648 * g_object_interface_list_properties:
649 * @g_iface: any interface vtable for the interface, or the default
650 * vtable for the interface
651 * @n_properties_p: location to store number of properties returned.
652 *
653 * Lists the properties of an interface.Generally, the interface
654 * vtable passed in as @g_iface will be the default vtable from
655 * g_type_default_interface_ref(), or, if you know the interface has
656 * already been loaded, g_type_default_interface_peek().
657 *
658 * Since: 2.4
659 *
660 * Returns: a pointer to an array of pointers to #GParamSpec
661 * structures. The paramspecs are owned by GLib, but the
662 * array should be freed with g_free() when you are done with
663 * it.
664 */
665 GParamSpec**
g_object_interface_list_properties(gpointer g_iface,guint * n_properties_p)666 g_object_interface_list_properties (gpointer g_iface,
667 guint *n_properties_p)
668 {
669 GTypeInterface *iface_class = g_iface;
670 GParamSpec **pspecs;
671 guint n;
672
673 g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface_class->g_type), NULL);
674
675 pspecs = g_param_spec_pool_list (pspec_pool,
676 iface_class->g_type,
677 &n);
678 if (n_properties_p)
679 *n_properties_p = n;
680
681 return pspecs;
682 }
683
684 static void
g_object_init(GObject * object)685 g_object_init (GObject *object)
686 {
687 object->ref_count = 1;
688 g_datalist_init (&object->qdata);
689
690 /* freeze object's notification queue, g_object_newv() preserves pairedness */
691 g_object_notify_queue_freeze (object, &property_notify_context);
692 /* enter construction list for notify_queue_thaw() and to allow construct-only properties */
693 G_LOCK (construction_mutex);
694 construction_objects = g_slist_prepend (construction_objects, object);
695 G_UNLOCK (construction_mutex);
696
697 #ifdef G_ENABLE_DEBUG
698 IF_DEBUG (OBJECTS)
699 {
700 G_LOCK (debug_objects);
701 debug_objects_count++;
702 g_hash_table_insert (debug_objects_ht, object, object);
703 G_UNLOCK (debug_objects);
704 }
705 #endif /* G_ENABLE_DEBUG */
706 }
707
708 static void
g_object_do_set_property(GObject * object,guint property_id,const GValue * value,GParamSpec * pspec)709 g_object_do_set_property (GObject *object,
710 guint property_id,
711 const GValue *value,
712 GParamSpec *pspec)
713 {
714 switch (property_id)
715 {
716 default:
717 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
718 break;
719 }
720 }
721
722 static void
g_object_do_get_property(GObject * object,guint property_id,GValue * value,GParamSpec * pspec)723 g_object_do_get_property (GObject *object,
724 guint property_id,
725 GValue *value,
726 GParamSpec *pspec)
727 {
728 switch (property_id)
729 {
730 default:
731 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
732 break;
733 }
734 }
735
736 static void
g_object_real_dispose(GObject * object)737 g_object_real_dispose (GObject *object)
738 {
739 g_signal_handlers_destroy (object);
740 g_datalist_id_set_data (&object->qdata, quark_closure_array, NULL);
741 g_datalist_id_set_data (&object->qdata, quark_weak_refs, NULL);
742 }
743
744 static void
g_object_finalize(GObject * object)745 g_object_finalize (GObject *object)
746 {
747 g_datalist_clear (&object->qdata);
748
749 #ifdef G_ENABLE_DEBUG
750 IF_DEBUG (OBJECTS)
751 {
752 G_LOCK (debug_objects);
753 g_assert (g_hash_table_lookup (debug_objects_ht, object) == object);
754 g_hash_table_remove (debug_objects_ht, object);
755 debug_objects_count--;
756 G_UNLOCK (debug_objects);
757 }
758 #endif /* G_ENABLE_DEBUG */
759 }
760
761
762 static void
g_object_dispatch_properties_changed(GObject * object,guint n_pspecs,GParamSpec ** pspecs)763 g_object_dispatch_properties_changed (GObject *object,
764 guint n_pspecs,
765 GParamSpec **pspecs)
766 {
767 guint i;
768
769 for (i = 0; i < n_pspecs; i++)
770 g_signal_emit (object, gobject_signals[NOTIFY], g_quark_from_string (pspecs[i]->name), pspecs[i]);
771 }
772
773 /**
774 * g_object_run_dispose:
775 * @object: a #GObject
776 *
777 * Releases all references to other objects. This can be used to break
778 * reference cycles.
779 *
780 * This functions should only be called from object system implementations.
781 */
782 void
g_object_run_dispose(GObject * object)783 g_object_run_dispose (GObject *object)
784 {
785 g_return_if_fail (G_IS_OBJECT (object));
786 g_return_if_fail (object->ref_count > 0);
787
788 g_object_ref (object);
789 G_OBJECT_GET_CLASS (object)->dispose (object);
790 g_object_unref (object);
791 }
792
793 /**
794 * g_object_freeze_notify:
795 * @object: a #GObject
796 *
797 * Increases the freeze count on @object. If the freeze count is
798 * non-zero, the emission of "notify" signals on @object is
799 * stopped. The signals are queued until the freeze count is decreased
800 * to zero.
801 *
802 * This is necessary for accessors that modify multiple properties to prevent
803 * premature notification while the object is still being modified.
804 */
805 void
g_object_freeze_notify(GObject * object)806 g_object_freeze_notify (GObject *object)
807 {
808 g_return_if_fail (G_IS_OBJECT (object));
809
810 if (g_atomic_int_get (&object->ref_count) == 0)
811 return;
812
813 g_object_ref (object);
814 g_object_notify_queue_freeze (object, &property_notify_context);
815 g_object_unref (object);
816 }
817
818 /**
819 * g_object_notify:
820 * @object: a #GObject
821 * @property_name: the name of a property installed on the class of @object.
822 *
823 * Emits a "notify" signal for the property @property_name on @object.
824 */
825 void
g_object_notify(GObject * object,const gchar * property_name)826 g_object_notify (GObject *object,
827 const gchar *property_name)
828 {
829 GParamSpec *pspec;
830
831 g_return_if_fail (G_IS_OBJECT (object));
832 g_return_if_fail (property_name != NULL);
833 if (g_atomic_int_get (&object->ref_count) == 0)
834 return;
835
836 g_object_ref (object);
837 /* We don't need to get the redirect target
838 * (by, e.g. calling g_object_class_find_property())
839 * because g_object_notify_queue_add() does that
840 */
841 pspec = g_param_spec_pool_lookup (pspec_pool,
842 property_name,
843 G_OBJECT_TYPE (object),
844 TRUE);
845
846 if (!pspec)
847 g_warning ("%s: object class `%s' has no property named `%s'",
848 G_STRFUNC,
849 G_OBJECT_TYPE_NAME (object),
850 property_name);
851 else
852 {
853 GObjectNotifyQueue *nqueue;
854
855 nqueue = g_object_notify_queue_freeze (object, &property_notify_context);
856 g_object_notify_queue_add (object, nqueue, pspec);
857 g_object_notify_queue_thaw (object, nqueue);
858 }
859 g_object_unref (object);
860 }
861
862 /**
863 * g_object_thaw_notify:
864 * @object: a #GObject
865 *
866 * Reverts the effect of a previous call to
867 * g_object_freeze_notify(). The freeze count is decreased on @object
868 * and when it reaches zero, all queued "notify" signals are emitted.
869 *
870 * It is an error to call this function when the freeze count is zero.
871 */
872 void
g_object_thaw_notify(GObject * object)873 g_object_thaw_notify (GObject *object)
874 {
875 GObjectNotifyQueue *nqueue;
876
877 g_return_if_fail (G_IS_OBJECT (object));
878 if (g_atomic_int_get (&object->ref_count) == 0)
879 return;
880
881 g_object_ref (object);
882 nqueue = g_object_notify_queue_from_object (object, &property_notify_context);
883 if (!nqueue || !nqueue->freeze_count)
884 g_warning ("%s: property-changed notification for %s(%p) is not frozen",
885 G_STRFUNC, G_OBJECT_TYPE_NAME (object), object);
886 else
887 g_object_notify_queue_thaw (object, nqueue);
888 g_object_unref (object);
889 }
890
891 static inline void
object_get_property(GObject * object,GParamSpec * pspec,GValue * value)892 object_get_property (GObject *object,
893 GParamSpec *pspec,
894 GValue *value)
895 {
896 GObjectClass *class = g_type_class_peek (pspec->owner_type);
897 guint param_id = PARAM_SPEC_PARAM_ID (pspec);
898 GParamSpec *redirect;
899
900 redirect = g_param_spec_get_redirect_target (pspec);
901 if (redirect)
902 pspec = redirect;
903
904 class->get_property (object, param_id, value, pspec);
905 }
906
907 static inline void
object_set_property(GObject * object,GParamSpec * pspec,const GValue * value,GObjectNotifyQueue * nqueue)908 object_set_property (GObject *object,
909 GParamSpec *pspec,
910 const GValue *value,
911 GObjectNotifyQueue *nqueue)
912 {
913 GValue tmp_value = { 0, };
914 GObjectClass *class = g_type_class_peek (pspec->owner_type);
915 guint param_id = PARAM_SPEC_PARAM_ID (pspec);
916 GParamSpec *redirect;
917
918 redirect = g_param_spec_get_redirect_target (pspec);
919 if (redirect)
920 pspec = redirect;
921
922 /* provide a copy to work from, convert (if necessary) and validate */
923 g_value_init (&tmp_value, G_PARAM_SPEC_VALUE_TYPE (pspec));
924 if (!g_value_transform (value, &tmp_value))
925 g_warning ("unable to set property `%s' of type `%s' from value of type `%s'",
926 pspec->name,
927 g_type_name (G_PARAM_SPEC_VALUE_TYPE (pspec)),
928 G_VALUE_TYPE_NAME (value));
929 else if (g_param_value_validate (pspec, &tmp_value) && !(pspec->flags & G_PARAM_LAX_VALIDATION))
930 {
931 gchar *contents = g_strdup_value_contents (value);
932
933 g_warning ("value \"%s\" of type `%s' is invalid or out of range for property `%s' of type `%s'",
934 contents,
935 G_VALUE_TYPE_NAME (value),
936 pspec->name,
937 g_type_name (G_PARAM_SPEC_VALUE_TYPE (pspec)));
938 g_free (contents);
939 }
940 else
941 {
942 class->set_property (object, param_id, &tmp_value, pspec);
943 g_object_notify_queue_add (object, nqueue, pspec);
944 }
945 g_value_unset (&tmp_value);
946 }
947
948 static void
object_interface_check_properties(gpointer func_data,gpointer g_iface)949 object_interface_check_properties (gpointer func_data,
950 gpointer g_iface)
951 {
952 GTypeInterface *iface_class = g_iface;
953 GObjectClass *class = g_type_class_peek (iface_class->g_instance_type);
954 GType iface_type = iface_class->g_type;
955 GParamSpec **pspecs;
956 guint n;
957
958 if (!G_IS_OBJECT_CLASS (class))
959 return;
960
961 pspecs = g_param_spec_pool_list (pspec_pool, iface_type, &n);
962
963 while (n--)
964 {
965 GParamSpec *class_pspec = g_param_spec_pool_lookup (pspec_pool,
966 pspecs[n]->name,
967 G_OBJECT_CLASS_TYPE (class),
968 TRUE);
969
970 if (!class_pspec)
971 {
972 g_critical ("Object class %s doesn't implement property "
973 "'%s' from interface '%s'",
974 g_type_name (G_OBJECT_CLASS_TYPE (class)),
975 pspecs[n]->name,
976 g_type_name (iface_type));
977
978 continue;
979 }
980
981 /* The implementation paramspec must have a less restrictive
982 * type than the interface parameter spec for set() and a
983 * more restrictive type for get(). We just require equality,
984 * rather than doing something more complicated checking
985 * the READABLE and WRITABLE flags. We also simplify here
986 * by only checking the value type, not the G_PARAM_SPEC_TYPE.
987 */
988 if (class_pspec &&
989 !g_type_is_a (G_PARAM_SPEC_VALUE_TYPE (pspecs[n]),
990 G_PARAM_SPEC_VALUE_TYPE (class_pspec)))
991 {
992 g_critical ("Property '%s' on class '%s' has type '%s' "
993 "which is different from the type '%s', "
994 "of the property on interface '%s'\n",
995 pspecs[n]->name,
996 g_type_name (G_OBJECT_CLASS_TYPE (class)),
997 g_type_name (G_PARAM_SPEC_VALUE_TYPE (class_pspec)),
998 g_type_name (G_PARAM_SPEC_VALUE_TYPE (pspecs[n])),
999 g_type_name (iface_type));
1000 }
1001
1002 #define SUBSET(a,b,mask) (((a) & ~(b) & (mask)) == 0)
1003
1004 /* CONSTRUCT and CONSTRUCT_ONLY add restrictions.
1005 * READABLE and WRITABLE remove restrictions. The implementation
1006 * paramspec must have less restrictive flags.
1007 */
1008 if (class_pspec &&
1009 (!SUBSET (class_pspec->flags,
1010 pspecs[n]->flags,
1011 G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY) ||
1012 !SUBSET (pspecs[n]->flags,
1013 class_pspec->flags,
1014 G_PARAM_READABLE | G_PARAM_WRITABLE)))
1015 {
1016 g_critical ("Flags for property '%s' on class '%s' "
1017 "are not compatible with the property on"
1018 "interface '%s'\n",
1019 pspecs[n]->name,
1020 g_type_name (G_OBJECT_CLASS_TYPE (class)),
1021 g_type_name (iface_type));
1022 }
1023 #undef SUBSET
1024 }
1025
1026 g_free (pspecs);
1027 }
1028
1029 GType
g_object_get_type(void)1030 g_object_get_type (void)
1031 {
1032 return G_TYPE_OBJECT;
1033 }
1034
1035 /**
1036 * g_object_new:
1037 * @object_type: the type id of the #GObject subtype to instantiate
1038 * @first_property_name: the name of the first property
1039 * @...: the value of the first property, followed optionally by more
1040 * name/value pairs, followed by %NULL
1041 *
1042 * Creates a new instance of a #GObject subtype and sets its properties.
1043 *
1044 * Construction parameters (see #G_PARAM_CONSTRUCT, #G_PARAM_CONSTRUCT_ONLY)
1045 * which are not explicitly specified are set to their default values.
1046 *
1047 * Returns: a new instance of @object_type
1048 */
1049 gpointer
g_object_new(GType object_type,const gchar * first_property_name,...)1050 g_object_new (GType object_type,
1051 const gchar *first_property_name,
1052 ...)
1053 {
1054 GObject *object;
1055 va_list var_args;
1056
1057 g_return_val_if_fail (G_TYPE_IS_OBJECT (object_type), NULL);
1058
1059 va_start (var_args, first_property_name);
1060 object = g_object_new_valist (object_type, first_property_name, var_args);
1061 va_end (var_args);
1062
1063 return object;
1064 }
1065
1066 static gboolean
slist_maybe_remove(GSList ** slist,gconstpointer data)1067 slist_maybe_remove (GSList **slist,
1068 gconstpointer data)
1069 {
1070 GSList *last = NULL, *node = *slist;
1071 while (node)
1072 {
1073 if (node->data == data)
1074 {
1075 if (last)
1076 last->next = node->next;
1077 else
1078 *slist = node->next;
1079 g_slist_free_1 (node);
1080 return TRUE;
1081 }
1082 last = node;
1083 node = last->next;
1084 }
1085 return FALSE;
1086 }
1087
1088 static inline gboolean
object_in_construction_list(GObject * object)1089 object_in_construction_list (GObject *object)
1090 {
1091 gboolean in_construction;
1092 G_LOCK (construction_mutex);
1093 in_construction = g_slist_find (construction_objects, object) != NULL;
1094 G_UNLOCK (construction_mutex);
1095 return in_construction;
1096 }
1097
1098 /**
1099 * g_object_newv:
1100 * @object_type: the type id of the #GObject subtype to instantiate
1101 * @n_parameters: the length of the @parameters array
1102 * @parameters: an array of #GParameter
1103 *
1104 * Creates a new instance of a #GObject subtype and sets its properties.
1105 *
1106 * Construction parameters (see #G_PARAM_CONSTRUCT, #G_PARAM_CONSTRUCT_ONLY)
1107 * which are not explicitly specified are set to their default values.
1108 *
1109 * Returns: a new instance of @object_type
1110 */
1111 gpointer
g_object_newv(GType object_type,guint n_parameters,GParameter * parameters)1112 g_object_newv (GType object_type,
1113 guint n_parameters,
1114 GParameter *parameters)
1115 {
1116 GObjectConstructParam *cparams, *oparams;
1117 GObjectNotifyQueue *nqueue = NULL; /* shouldn't be initialized, just to silence compiler */
1118 GObject *object;
1119 GObjectClass *class, *unref_class = NULL;
1120 GSList *slist;
1121 guint n_total_cparams = 0, n_cparams = 0, n_oparams = 0, n_cvalues;
1122 GValue *cvalues;
1123 GList *clist = NULL;
1124 gboolean newly_constructed;
1125 guint i;
1126
1127 g_return_val_if_fail (G_TYPE_IS_OBJECT (object_type), NULL);
1128
1129 class = g_type_class_peek_static (object_type);
1130 if (!class)
1131 class = unref_class = g_type_class_ref (object_type);
1132 for (slist = class->construct_properties; slist; slist = slist->next)
1133 {
1134 clist = g_list_prepend (clist, slist->data);
1135 n_total_cparams += 1;
1136 }
1137
1138 /* collect parameters, sort into construction and normal ones */
1139 oparams = g_new (GObjectConstructParam, n_parameters);
1140 cparams = g_new (GObjectConstructParam, n_total_cparams);
1141 for (i = 0; i < n_parameters; i++)
1142 {
1143 GValue *value = ¶meters[i].value;
1144 GParamSpec *pspec = g_param_spec_pool_lookup (pspec_pool,
1145 parameters[i].name,
1146 object_type,
1147 TRUE);
1148 if (!pspec)
1149 {
1150 g_warning ("%s: object class `%s' has no property named `%s'",
1151 G_STRFUNC,
1152 g_type_name (object_type),
1153 parameters[i].name);
1154 continue;
1155 }
1156 if (!(pspec->flags & G_PARAM_WRITABLE))
1157 {
1158 g_warning ("%s: property `%s' of object class `%s' is not writable",
1159 G_STRFUNC,
1160 pspec->name,
1161 g_type_name (object_type));
1162 continue;
1163 }
1164 if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))
1165 {
1166 GList *list = g_list_find (clist, pspec);
1167
1168 if (!list)
1169 {
1170 g_warning ("%s: construct property \"%s\" for object `%s' can't be set twice",
1171 G_STRFUNC, pspec->name, g_type_name (object_type));
1172 continue;
1173 }
1174 cparams[n_cparams].pspec = pspec;
1175 cparams[n_cparams].value = value;
1176 n_cparams++;
1177 if (!list->prev)
1178 clist = list->next;
1179 else
1180 list->prev->next = list->next;
1181 if (list->next)
1182 list->next->prev = list->prev;
1183 g_list_free_1 (list);
1184 }
1185 else
1186 {
1187 oparams[n_oparams].pspec = pspec;
1188 oparams[n_oparams].value = value;
1189 n_oparams++;
1190 }
1191 }
1192
1193 /* set remaining construction properties to default values */
1194 n_cvalues = n_total_cparams - n_cparams;
1195 cvalues = g_new (GValue, n_cvalues);
1196 while (clist)
1197 {
1198 GList *tmp = clist->next;
1199 GParamSpec *pspec = clist->data;
1200 GValue *value = cvalues + n_total_cparams - n_cparams - 1;
1201
1202 value->g_type = 0;
1203 g_value_init (value, G_PARAM_SPEC_VALUE_TYPE (pspec));
1204 g_param_value_set_default (pspec, value);
1205
1206 cparams[n_cparams].pspec = pspec;
1207 cparams[n_cparams].value = value;
1208 n_cparams++;
1209
1210 g_list_free_1 (clist);
1211 clist = tmp;
1212 }
1213
1214 /* construct object from construction parameters */
1215 object = class->constructor (object_type, n_total_cparams, cparams);
1216 /* free construction values */
1217 g_free (cparams);
1218 while (n_cvalues--)
1219 g_value_unset (cvalues + n_cvalues);
1220 g_free (cvalues);
1221
1222 /* adjust freeze_count according to g_object_init() and remaining properties */
1223 G_LOCK (construction_mutex);
1224 newly_constructed = slist_maybe_remove (&construction_objects, object);
1225 G_UNLOCK (construction_mutex);
1226 if (newly_constructed || n_oparams)
1227 nqueue = g_object_notify_queue_freeze (object, &property_notify_context);
1228 if (newly_constructed)
1229 g_object_notify_queue_thaw (object, nqueue);
1230
1231 /* run 'constructed' handler if there is one */
1232 if (newly_constructed && class->constructed)
1233 class->constructed (object);
1234
1235 /* set remaining properties */
1236 for (i = 0; i < n_oparams; i++)
1237 object_set_property (object, oparams[i].pspec, oparams[i].value, nqueue);
1238 g_free (oparams);
1239
1240 /* release our own freeze count and handle notifications */
1241 if (newly_constructed || n_oparams)
1242 g_object_notify_queue_thaw (object, nqueue);
1243
1244 if (unref_class)
1245 g_type_class_unref (unref_class);
1246
1247 return object;
1248 }
1249
1250 /**
1251 * g_object_new_valist:
1252 * @object_type: the type id of the #GObject subtype to instantiate
1253 * @first_property_name: the name of the first property
1254 * @var_args: the value of the first property, followed optionally by more
1255 * name/value pairs, followed by %NULL
1256 *
1257 * Creates a new instance of a #GObject subtype and sets its properties.
1258 *
1259 * Construction parameters (see #G_PARAM_CONSTRUCT, #G_PARAM_CONSTRUCT_ONLY)
1260 * which are not explicitly specified are set to their default values.
1261 *
1262 * Returns: a new instance of @object_type
1263 */
1264 GObject*
g_object_new_valist(GType object_type,const gchar * first_property_name,va_list var_args)1265 g_object_new_valist (GType object_type,
1266 const gchar *first_property_name,
1267 va_list var_args)
1268 {
1269 GObjectClass *class;
1270 GParameter *params;
1271 const gchar *name;
1272 GObject *object;
1273 guint n_params = 0, n_alloced_params = 16;
1274
1275 g_return_val_if_fail (G_TYPE_IS_OBJECT (object_type), NULL);
1276
1277 if (!first_property_name)
1278 return g_object_newv (object_type, 0, NULL);
1279
1280 class = g_type_class_ref (object_type);
1281
1282 params = g_new (GParameter, n_alloced_params);
1283 name = first_property_name;
1284 while (name)
1285 {
1286 gchar *error = NULL;
1287 GParamSpec *pspec = g_param_spec_pool_lookup (pspec_pool,
1288 name,
1289 object_type,
1290 TRUE);
1291 if (!pspec)
1292 {
1293 g_warning ("%s: object class `%s' has no property named `%s'",
1294 G_STRFUNC,
1295 g_type_name (object_type),
1296 name);
1297 break;
1298 }
1299 if (n_params >= n_alloced_params)
1300 {
1301 n_alloced_params += 16;
1302 params = g_renew (GParameter, params, n_alloced_params);
1303 }
1304 params[n_params].name = name;
1305 params[n_params].value.g_type = 0;
1306 g_value_init (¶ms[n_params].value, G_PARAM_SPEC_VALUE_TYPE (pspec));
1307 G_VALUE_COLLECT (¶ms[n_params].value, var_args, 0, &error);
1308 if (error)
1309 {
1310 g_warning ("%s: %s", G_STRFUNC, error);
1311 g_free (error);
1312 g_value_unset (¶ms[n_params].value);
1313 break;
1314 }
1315 n_params++;
1316 name = va_arg (var_args, gchar*);
1317 }
1318
1319 object = g_object_newv (object_type, n_params, params);
1320
1321 while (n_params--)
1322 g_value_unset (¶ms[n_params].value);
1323 g_free (params);
1324
1325 g_type_class_unref (class);
1326
1327 return object;
1328 }
1329
1330 static GObject*
g_object_constructor(GType type,guint n_construct_properties,GObjectConstructParam * construct_params)1331 g_object_constructor (GType type,
1332 guint n_construct_properties,
1333 GObjectConstructParam *construct_params)
1334 {
1335 GObject *object;
1336
1337 /* create object */
1338 object = (GObject*) g_type_create_instance (type);
1339
1340 /* set construction parameters */
1341 if (n_construct_properties)
1342 {
1343 GObjectNotifyQueue *nqueue = g_object_notify_queue_freeze (object, &property_notify_context);
1344
1345 /* set construct properties */
1346 while (n_construct_properties--)
1347 {
1348 GValue *value = construct_params->value;
1349 GParamSpec *pspec = construct_params->pspec;
1350
1351 construct_params++;
1352 object_set_property (object, pspec, value, nqueue);
1353 }
1354 g_object_notify_queue_thaw (object, nqueue);
1355 /* the notification queue is still frozen from g_object_init(), so
1356 * we don't need to handle it here, g_object_newv() takes
1357 * care of that
1358 */
1359 }
1360
1361 return object;
1362 }
1363
1364 /**
1365 * g_object_set_valist:
1366 * @object: a #GObject
1367 * @first_property_name: name of the first property to set
1368 * @var_args: value for the first property, followed optionally by more
1369 * name/value pairs, followed by %NULL
1370 *
1371 * Sets properties on an object.
1372 */
1373 void
g_object_set_valist(GObject * object,const gchar * first_property_name,va_list var_args)1374 g_object_set_valist (GObject *object,
1375 const gchar *first_property_name,
1376 va_list var_args)
1377 {
1378 GObjectNotifyQueue *nqueue;
1379 const gchar *name;
1380
1381 g_return_if_fail (G_IS_OBJECT (object));
1382
1383 g_object_ref (object);
1384 nqueue = g_object_notify_queue_freeze (object, &property_notify_context);
1385
1386 name = first_property_name;
1387 while (name)
1388 {
1389 GValue value = { 0, };
1390 GParamSpec *pspec;
1391 gchar *error = NULL;
1392
1393 pspec = g_param_spec_pool_lookup (pspec_pool,
1394 name,
1395 G_OBJECT_TYPE (object),
1396 TRUE);
1397 if (!pspec)
1398 {
1399 g_warning ("%s: object class `%s' has no property named `%s'",
1400 G_STRFUNC,
1401 G_OBJECT_TYPE_NAME (object),
1402 name);
1403 break;
1404 }
1405 if (!(pspec->flags & G_PARAM_WRITABLE))
1406 {
1407 g_warning ("%s: property `%s' of object class `%s' is not writable",
1408 G_STRFUNC,
1409 pspec->name,
1410 G_OBJECT_TYPE_NAME (object));
1411 break;
1412 }
1413 if ((pspec->flags & G_PARAM_CONSTRUCT_ONLY) && !object_in_construction_list (object))
1414 {
1415 g_warning ("%s: construct property \"%s\" for object `%s' can't be set after construction",
1416 G_STRFUNC, pspec->name, G_OBJECT_TYPE_NAME (object));
1417 break;
1418 }
1419
1420 g_value_init (&value, G_PARAM_SPEC_VALUE_TYPE (pspec));
1421
1422 G_VALUE_COLLECT (&value, var_args, 0, &error);
1423 if (error)
1424 {
1425 g_warning ("%s: %s", G_STRFUNC, error);
1426 g_free (error);
1427 g_value_unset (&value);
1428 break;
1429 }
1430
1431 object_set_property (object, pspec, &value, nqueue);
1432 g_value_unset (&value);
1433
1434 name = va_arg (var_args, gchar*);
1435 }
1436
1437 g_object_notify_queue_thaw (object, nqueue);
1438 g_object_unref (object);
1439 }
1440
1441 /**
1442 * g_object_get_valist:
1443 * @object: a #GObject
1444 * @first_property_name: name of the first property to get
1445 * @var_args: return location for the first property, followed optionally by more
1446 * name/return location pairs, followed by %NULL
1447 *
1448 * Gets properties of an object.
1449 *
1450 * In general, a copy is made of the property contents and the caller
1451 * is responsible for freeing the memory in the appropriate manner for
1452 * the type, for instance by calling g_free() or g_object_unref().
1453 *
1454 * See g_object_get().
1455 */
1456 void
g_object_get_valist(GObject * object,const gchar * first_property_name,va_list var_args)1457 g_object_get_valist (GObject *object,
1458 const gchar *first_property_name,
1459 va_list var_args)
1460 {
1461 const gchar *name;
1462
1463 g_return_if_fail (G_IS_OBJECT (object));
1464
1465 g_object_ref (object);
1466
1467 name = first_property_name;
1468
1469 while (name)
1470 {
1471 GValue value = { 0, };
1472 GParamSpec *pspec;
1473 gchar *error;
1474
1475 pspec = g_param_spec_pool_lookup (pspec_pool,
1476 name,
1477 G_OBJECT_TYPE (object),
1478 TRUE);
1479 if (!pspec)
1480 {
1481 g_warning ("%s: object class `%s' has no property named `%s'",
1482 G_STRFUNC,
1483 G_OBJECT_TYPE_NAME (object),
1484 name);
1485 break;
1486 }
1487 if (!(pspec->flags & G_PARAM_READABLE))
1488 {
1489 g_warning ("%s: property `%s' of object class `%s' is not readable",
1490 G_STRFUNC,
1491 pspec->name,
1492 G_OBJECT_TYPE_NAME (object));
1493 break;
1494 }
1495
1496 g_value_init (&value, G_PARAM_SPEC_VALUE_TYPE (pspec));
1497
1498 object_get_property (object, pspec, &value);
1499
1500 G_VALUE_LCOPY (&value, var_args, 0, &error);
1501 if (error)
1502 {
1503 g_warning ("%s: %s", G_STRFUNC, error);
1504 g_free (error);
1505 g_value_unset (&value);
1506 break;
1507 }
1508
1509 g_value_unset (&value);
1510
1511 name = va_arg (var_args, gchar*);
1512 }
1513
1514 g_object_unref (object);
1515 }
1516
1517 /**
1518 * g_object_set:
1519 * @object: a #GObject
1520 * @first_property_name: name of the first property to set
1521 * @...: value for the first property, followed optionally by more
1522 * name/value pairs, followed by %NULL
1523 *
1524 * Sets properties on an object.
1525 */
1526 void
g_object_set(gpointer _object,const gchar * first_property_name,...)1527 g_object_set (gpointer _object,
1528 const gchar *first_property_name,
1529 ...)
1530 {
1531 GObject *object = _object;
1532 va_list var_args;
1533
1534 g_return_if_fail (G_IS_OBJECT (object));
1535
1536 va_start (var_args, first_property_name);
1537 g_object_set_valist (object, first_property_name, var_args);
1538 va_end (var_args);
1539 }
1540
1541 /**
1542 * g_object_get:
1543 * @object: a #GObject
1544 * @first_property_name: name of the first property to get
1545 * @...: return location for the first property, followed optionally by more
1546 * name/return location pairs, followed by %NULL
1547 *
1548 * Gets properties of an object.
1549 *
1550 * In general, a copy is made of the property contents and the caller
1551 * is responsible for freeing the memory in the appropriate manner for
1552 * the type, for instance by calling g_free() or g_object_unref().
1553 *
1554 * <example>
1555 * <title>Using g_object_get(<!-- -->)</title>
1556 * An example of using g_object_get() to get the contents
1557 * of three properties - one of type #G_TYPE_INT,
1558 * one of type #G_TYPE_STRING, and one of type #G_TYPE_OBJECT:
1559 * <programlisting>
1560 * gint intval;
1561 * gchar *strval;
1562 * GObject *objval;
1563 *
1564 * g_object_get (my_object,
1565 * "int-property", &intval,
1566 * "str-property", &strval,
1567 * "obj-property", &objval,
1568 * NULL);
1569 *
1570 * // Do something with intval, strval, objval
1571 *
1572 * g_free (strval);
1573 * g_object_unref (objval);
1574 * </programlisting>
1575 * </example>
1576 */
1577 void
g_object_get(gpointer _object,const gchar * first_property_name,...)1578 g_object_get (gpointer _object,
1579 const gchar *first_property_name,
1580 ...)
1581 {
1582 GObject *object = _object;
1583 va_list var_args;
1584
1585 g_return_if_fail (G_IS_OBJECT (object));
1586
1587 va_start (var_args, first_property_name);
1588 g_object_get_valist (object, first_property_name, var_args);
1589 va_end (var_args);
1590 }
1591
1592 /**
1593 * g_object_set_property:
1594 * @object: a #GObject
1595 * @property_name: the name of the property to set
1596 * @value: the value
1597 *
1598 * Sets a property on an object.
1599 */
1600 void
g_object_set_property(GObject * object,const gchar * property_name,const GValue * value)1601 g_object_set_property (GObject *object,
1602 const gchar *property_name,
1603 const GValue *value)
1604 {
1605 GObjectNotifyQueue *nqueue;
1606 GParamSpec *pspec;
1607
1608 g_return_if_fail (G_IS_OBJECT (object));
1609 g_return_if_fail (property_name != NULL);
1610 g_return_if_fail (G_IS_VALUE (value));
1611
1612 g_object_ref (object);
1613 nqueue = g_object_notify_queue_freeze (object, &property_notify_context);
1614
1615 pspec = g_param_spec_pool_lookup (pspec_pool,
1616 property_name,
1617 G_OBJECT_TYPE (object),
1618 TRUE);
1619 if (!pspec)
1620 g_warning ("%s: object class `%s' has no property named `%s'",
1621 G_STRFUNC,
1622 G_OBJECT_TYPE_NAME (object),
1623 property_name);
1624 else if (!(pspec->flags & G_PARAM_WRITABLE))
1625 g_warning ("%s: property `%s' of object class `%s' is not writable",
1626 G_STRFUNC,
1627 pspec->name,
1628 G_OBJECT_TYPE_NAME (object));
1629 else if ((pspec->flags & G_PARAM_CONSTRUCT_ONLY) && !object_in_construction_list (object))
1630 g_warning ("%s: construct property \"%s\" for object `%s' can't be set after construction",
1631 G_STRFUNC, pspec->name, G_OBJECT_TYPE_NAME (object));
1632 else
1633 object_set_property (object, pspec, value, nqueue);
1634
1635 g_object_notify_queue_thaw (object, nqueue);
1636 g_object_unref (object);
1637 }
1638
1639 /**
1640 * g_object_get_property:
1641 * @object: a #GObject
1642 * @property_name: the name of the property to get
1643 * @value: return location for the property value
1644 *
1645 * Gets a property of an object.
1646 *
1647 * In general, a copy is made of the property contents and the caller is
1648 * responsible for freeing the memory by calling g_value_unset().
1649 *
1650 * Note that g_object_get_property() is really intended for language
1651 * bindings, g_object_get() is much more convenient for C programming.
1652 */
1653 void
g_object_get_property(GObject * object,const gchar * property_name,GValue * value)1654 g_object_get_property (GObject *object,
1655 const gchar *property_name,
1656 GValue *value)
1657 {
1658 GParamSpec *pspec;
1659
1660 g_return_if_fail (G_IS_OBJECT (object));
1661 g_return_if_fail (property_name != NULL);
1662 g_return_if_fail (G_IS_VALUE (value));
1663
1664 g_object_ref (object);
1665
1666 pspec = g_param_spec_pool_lookup (pspec_pool,
1667 property_name,
1668 G_OBJECT_TYPE (object),
1669 TRUE);
1670 if (!pspec)
1671 g_warning ("%s: object class `%s' has no property named `%s'",
1672 G_STRFUNC,
1673 G_OBJECT_TYPE_NAME (object),
1674 property_name);
1675 else if (!(pspec->flags & G_PARAM_READABLE))
1676 g_warning ("%s: property `%s' of object class `%s' is not readable",
1677 G_STRFUNC,
1678 pspec->name,
1679 G_OBJECT_TYPE_NAME (object));
1680 else
1681 {
1682 GValue *prop_value, tmp_value = { 0, };
1683
1684 /* auto-conversion of the callers value type
1685 */
1686 if (G_VALUE_TYPE (value) == G_PARAM_SPEC_VALUE_TYPE (pspec))
1687 {
1688 g_value_reset (value);
1689 prop_value = value;
1690 }
1691 else if (!g_value_type_transformable (G_PARAM_SPEC_VALUE_TYPE (pspec), G_VALUE_TYPE (value)))
1692 {
1693 g_warning ("%s: can't retrieve property `%s' of type `%s' as value of type `%s'",
1694 G_STRFUNC, pspec->name,
1695 g_type_name (G_PARAM_SPEC_VALUE_TYPE (pspec)),
1696 G_VALUE_TYPE_NAME (value));
1697 g_object_unref (object);
1698 return;
1699 }
1700 else
1701 {
1702 g_value_init (&tmp_value, G_PARAM_SPEC_VALUE_TYPE (pspec));
1703 prop_value = &tmp_value;
1704 }
1705 object_get_property (object, pspec, prop_value);
1706 if (prop_value != value)
1707 {
1708 g_value_transform (prop_value, value);
1709 g_value_unset (&tmp_value);
1710 }
1711 }
1712
1713 g_object_unref (object);
1714 }
1715
1716 /**
1717 * g_object_connect:
1718 * @object: a #GObject
1719 * @signal_spec: the spec for the first signal
1720 * @...: #GCallback for the first signal, followed by data for the
1721 * first signal, followed optionally by more signal
1722 * spec/callback/data triples, followed by %NULL
1723 *
1724 * A convenience function to connect multiple signals at once.
1725 *
1726 * The signal specs expected by this function have the form
1727 * "modifier::signal_name", where modifier can be one of the following:
1728 * <variablelist>
1729 * <varlistentry>
1730 * <term>signal</term>
1731 * <listitem><para>
1732 * equivalent to <literal>g_signal_connect_data (..., NULL, 0)</literal>
1733 * </para></listitem>
1734 * </varlistentry>
1735 * <varlistentry>
1736 * <term>object_signal</term>
1737 * <term>object-signal</term>
1738 * <listitem><para>
1739 * equivalent to <literal>g_signal_connect_object (..., 0)</literal>
1740 * </para></listitem>
1741 * </varlistentry>
1742 * <varlistentry>
1743 * <term>swapped_signal</term>
1744 * <term>swapped-signal</term>
1745 * <listitem><para>
1746 * equivalent to <literal>g_signal_connect_data (..., NULL, G_CONNECT_SWAPPED)</literal>
1747 * </para></listitem>
1748 * </varlistentry>
1749 * <varlistentry>
1750 * <term>swapped_object_signal</term>
1751 * <term>swapped-object-signal</term>
1752 * <listitem><para>
1753 * equivalent to <literal>g_signal_connect_object (..., G_CONNECT_SWAPPED)</literal>
1754 * </para></listitem>
1755 * </varlistentry>
1756 * <varlistentry>
1757 * <term>signal_after</term>
1758 * <term>signal-after</term>
1759 * <listitem><para>
1760 * equivalent to <literal>g_signal_connect_data (..., NULL, G_CONNECT_AFTER)</literal>
1761 * </para></listitem>
1762 * </varlistentry>
1763 * <varlistentry>
1764 * <term>object_signal_after</term>
1765 * <term>object-signal-after</term>
1766 * <listitem><para>
1767 * equivalent to <literal>g_signal_connect_object (..., G_CONNECT_AFTER)</literal>
1768 * </para></listitem>
1769 * </varlistentry>
1770 * <varlistentry>
1771 * <term>swapped_signal_after</term>
1772 * <term>swapped-signal-after</term>
1773 * <listitem><para>
1774 * equivalent to <literal>g_signal_connect_data (..., NULL, G_CONNECT_SWAPPED | G_CONNECT_AFTER)</literal>
1775 * </para></listitem>
1776 * </varlistentry>
1777 * <varlistentry>
1778 * <term>swapped_object_signal_after</term>
1779 * <term>swapped-object-signal-after</term>
1780 * <listitem><para>
1781 * equivalent to <literal>g_signal_connect_object (..., G_CONNECT_SWAPPED | G_CONNECT_AFTER)</literal>
1782 * </para></listitem>
1783 * </varlistentry>
1784 * </variablelist>
1785 *
1786 * |[
1787 * menu->toplevel = g_object_connect (g_object_new (GTK_TYPE_WINDOW,
1788 * "type", GTK_WINDOW_POPUP,
1789 * "child", menu,
1790 * NULL),
1791 * "signal::event", gtk_menu_window_event, menu,
1792 * "signal::size_request", gtk_menu_window_size_request, menu,
1793 * "signal::destroy", gtk_widget_destroyed, &menu->toplevel,
1794 * NULL);
1795 * ]|
1796 *
1797 * Returns: @object
1798 */
1799 gpointer
g_object_connect(gpointer _object,const gchar * signal_spec,...)1800 g_object_connect (gpointer _object,
1801 const gchar *signal_spec,
1802 ...)
1803 {
1804 GObject *object = _object;
1805 va_list var_args;
1806
1807 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
1808 g_return_val_if_fail (object->ref_count > 0, object);
1809
1810 va_start (var_args, signal_spec);
1811 while (signal_spec)
1812 {
1813 GCallback callback = va_arg (var_args, GCallback);
1814 gpointer data = va_arg (var_args, gpointer);
1815 gulong sid;
1816
1817 if (strncmp (signal_spec, "signal::", 8) == 0)
1818 sid = g_signal_connect_data (object, signal_spec + 8,
1819 callback, data, NULL,
1820 0);
1821 else if (strncmp (signal_spec, "object_signal::", 15) == 0 ||
1822 strncmp (signal_spec, "object-signal::", 15) == 0)
1823 sid = g_signal_connect_object (object, signal_spec + 15,
1824 callback, data,
1825 0);
1826 else if (strncmp (signal_spec, "swapped_signal::", 16) == 0 ||
1827 strncmp (signal_spec, "swapped-signal::", 16) == 0)
1828 sid = g_signal_connect_data (object, signal_spec + 16,
1829 callback, data, NULL,
1830 G_CONNECT_SWAPPED);
1831 else if (strncmp (signal_spec, "swapped_object_signal::", 23) == 0 ||
1832 strncmp (signal_spec, "swapped-object-signal::", 23) == 0)
1833 sid = g_signal_connect_object (object, signal_spec + 23,
1834 callback, data,
1835 G_CONNECT_SWAPPED);
1836 else if (strncmp (signal_spec, "signal_after::", 14) == 0 ||
1837 strncmp (signal_spec, "signal-after::", 14) == 0)
1838 sid = g_signal_connect_data (object, signal_spec + 14,
1839 callback, data, NULL,
1840 G_CONNECT_AFTER);
1841 else if (strncmp (signal_spec, "object_signal_after::", 21) == 0 ||
1842 strncmp (signal_spec, "object-signal-after::", 21) == 0)
1843 sid = g_signal_connect_object (object, signal_spec + 21,
1844 callback, data,
1845 G_CONNECT_AFTER);
1846 else if (strncmp (signal_spec, "swapped_signal_after::", 22) == 0 ||
1847 strncmp (signal_spec, "swapped-signal-after::", 22) == 0)
1848 sid = g_signal_connect_data (object, signal_spec + 22,
1849 callback, data, NULL,
1850 G_CONNECT_SWAPPED | G_CONNECT_AFTER);
1851 else if (strncmp (signal_spec, "swapped_object_signal_after::", 29) == 0 ||
1852 strncmp (signal_spec, "swapped-object-signal-after::", 29) == 0)
1853 sid = g_signal_connect_object (object, signal_spec + 29,
1854 callback, data,
1855 G_CONNECT_SWAPPED | G_CONNECT_AFTER);
1856 else
1857 {
1858 g_warning ("%s: invalid signal spec \"%s\"", G_STRFUNC, signal_spec);
1859 break;
1860 }
1861 signal_spec = va_arg (var_args, gchar*);
1862 }
1863 va_end (var_args);
1864
1865 return object;
1866 }
1867
1868 /**
1869 * g_object_disconnect:
1870 * @object: a #GObject
1871 * @signal_spec: the spec for the first signal
1872 * @...: #GCallback for the first signal, followed by data for the first signal,
1873 * followed optionally by more signal spec/callback/data triples,
1874 * followed by %NULL
1875 *
1876 * A convenience function to disconnect multiple signals at once.
1877 *
1878 * The signal specs expected by this function have the form
1879 * "any_signal", which means to disconnect any signal with matching
1880 * callback and data, or "any_signal::signal_name", which only
1881 * disconnects the signal named "signal_name".
1882 */
1883 void
g_object_disconnect(gpointer _object,const gchar * signal_spec,...)1884 g_object_disconnect (gpointer _object,
1885 const gchar *signal_spec,
1886 ...)
1887 {
1888 GObject *object = _object;
1889 va_list var_args;
1890
1891 g_return_if_fail (G_IS_OBJECT (object));
1892 g_return_if_fail (object->ref_count > 0);
1893
1894 va_start (var_args, signal_spec);
1895 while (signal_spec)
1896 {
1897 GCallback callback = va_arg (var_args, GCallback);
1898 gpointer data = va_arg (var_args, gpointer);
1899 guint sid = 0, detail = 0, mask = 0;
1900
1901 if (strncmp (signal_spec, "any_signal::", 12) == 0 ||
1902 strncmp (signal_spec, "any-signal::", 12) == 0)
1903 {
1904 signal_spec += 12;
1905 mask = G_SIGNAL_MATCH_ID | G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA;
1906 }
1907 else if (strcmp (signal_spec, "any_signal") == 0 ||
1908 strcmp (signal_spec, "any-signal") == 0)
1909 {
1910 signal_spec += 10;
1911 mask = G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA;
1912 }
1913 else
1914 {
1915 g_warning ("%s: invalid signal spec \"%s\"", G_STRFUNC, signal_spec);
1916 break;
1917 }
1918
1919 if ((mask & G_SIGNAL_MATCH_ID) &&
1920 !g_signal_parse_name (signal_spec, G_OBJECT_TYPE (object), &sid, &detail, FALSE))
1921 g_warning ("%s: invalid signal name \"%s\"", G_STRFUNC, signal_spec);
1922 else if (!g_signal_handlers_disconnect_matched (object, mask | (detail ? G_SIGNAL_MATCH_DETAIL : 0),
1923 sid, detail,
1924 NULL, (gpointer)callback, data))
1925 g_warning ("%s: signal handler %p(%p) is not connected", G_STRFUNC, callback, data);
1926 signal_spec = va_arg (var_args, gchar*);
1927 }
1928 va_end (var_args);
1929 }
1930
1931 typedef struct {
1932 GObject *object;
1933 guint n_weak_refs;
1934 struct {
1935 GWeakNotify notify;
1936 gpointer data;
1937 } weak_refs[1]; /* flexible array */
1938 } WeakRefStack;
1939
1940 static void
weak_refs_notify(gpointer data)1941 weak_refs_notify (gpointer data)
1942 {
1943 WeakRefStack *wstack = data;
1944 guint i;
1945
1946 for (i = 0; i < wstack->n_weak_refs; i++)
1947 wstack->weak_refs[i].notify (wstack->weak_refs[i].data, wstack->object);
1948 g_free (wstack);
1949 }
1950
1951 /**
1952 * g_object_weak_ref:
1953 * @object: #GObject to reference weakly
1954 * @notify: callback to invoke before the object is freed
1955 * @data: extra data to pass to notify
1956 *
1957 * Adds a weak reference callback to an object. Weak references are
1958 * used for notification when an object is finalized. They are called
1959 * "weak references" because they allow you to safely hold a pointer
1960 * to an object without calling g_object_ref() (g_object_ref() adds a
1961 * strong reference, that is, forces the object to stay alive).
1962 */
1963 void
g_object_weak_ref(GObject * object,GWeakNotify notify,gpointer data)1964 g_object_weak_ref (GObject *object,
1965 GWeakNotify notify,
1966 gpointer data)
1967 {
1968 WeakRefStack *wstack;
1969 guint i;
1970
1971 g_return_if_fail (G_IS_OBJECT (object));
1972 g_return_if_fail (notify != NULL);
1973 g_return_if_fail (object->ref_count >= 1);
1974
1975 wstack = g_datalist_id_remove_no_notify (&object->qdata, quark_weak_refs);
1976 if (wstack)
1977 {
1978 i = wstack->n_weak_refs++;
1979 wstack = g_realloc (wstack, sizeof (*wstack) + sizeof (wstack->weak_refs[0]) * i);
1980 }
1981 else
1982 {
1983 wstack = g_renew (WeakRefStack, NULL, 1);
1984 wstack->object = object;
1985 wstack->n_weak_refs = 1;
1986 i = 0;
1987 }
1988 wstack->weak_refs[i].notify = notify;
1989 wstack->weak_refs[i].data = data;
1990 g_datalist_id_set_data_full (&object->qdata, quark_weak_refs, wstack, weak_refs_notify);
1991 }
1992
1993 /**
1994 * g_object_weak_unref:
1995 * @object: #GObject to remove a weak reference from
1996 * @notify: callback to search for
1997 * @data: data to search for
1998 *
1999 * Removes a weak reference callback to an object.
2000 */
2001 void
g_object_weak_unref(GObject * object,GWeakNotify notify,gpointer data)2002 g_object_weak_unref (GObject *object,
2003 GWeakNotify notify,
2004 gpointer data)
2005 {
2006 WeakRefStack *wstack;
2007 gboolean found_one = FALSE;
2008
2009 g_return_if_fail (G_IS_OBJECT (object));
2010 g_return_if_fail (notify != NULL);
2011
2012 wstack = g_datalist_id_get_data (&object->qdata, quark_weak_refs);
2013 if (wstack)
2014 {
2015 guint i;
2016
2017 for (i = 0; i < wstack->n_weak_refs; i++)
2018 if (wstack->weak_refs[i].notify == notify &&
2019 wstack->weak_refs[i].data == data)
2020 {
2021 found_one = TRUE;
2022 wstack->n_weak_refs -= 1;
2023 if (i != wstack->n_weak_refs)
2024 wstack->weak_refs[i] = wstack->weak_refs[wstack->n_weak_refs];
2025
2026 break;
2027 }
2028 }
2029 if (!found_one)
2030 g_warning ("%s: couldn't find weak ref %p(%p)", G_STRFUNC, notify, data);
2031 }
2032
2033 /**
2034 * g_object_add_weak_pointer:
2035 * @object: The object that should be weak referenced.
2036 * @weak_pointer_location: The memory address of a pointer.
2037 *
2038 * Adds a weak reference from weak_pointer to @object to indicate that
2039 * the pointer located at @weak_pointer_location is only valid during
2040 * the lifetime of @object. When the @object is finalized,
2041 * @weak_pointer will be set to %NULL.
2042 */
2043 void
g_object_add_weak_pointer(GObject * object,gpointer * weak_pointer_location)2044 g_object_add_weak_pointer (GObject *object,
2045 gpointer *weak_pointer_location)
2046 {
2047 g_return_if_fail (G_IS_OBJECT (object));
2048 g_return_if_fail (weak_pointer_location != NULL);
2049
2050 g_object_weak_ref (object,
2051 (GWeakNotify) g_nullify_pointer,
2052 weak_pointer_location);
2053 }
2054
2055 /**
2056 * g_object_remove_weak_pointer:
2057 * @object: The object that is weak referenced.
2058 * @weak_pointer_location: The memory address of a pointer.
2059 *
2060 * Removes a weak reference from @object that was previously added
2061 * using g_object_add_weak_pointer(). The @weak_pointer_location has
2062 * to match the one used with g_object_add_weak_pointer().
2063 */
2064 void
g_object_remove_weak_pointer(GObject * object,gpointer * weak_pointer_location)2065 g_object_remove_weak_pointer (GObject *object,
2066 gpointer *weak_pointer_location)
2067 {
2068 g_return_if_fail (G_IS_OBJECT (object));
2069 g_return_if_fail (weak_pointer_location != NULL);
2070
2071 g_object_weak_unref (object,
2072 (GWeakNotify) g_nullify_pointer,
2073 weak_pointer_location);
2074 }
2075
2076 static guint
object_floating_flag_handler(GObject * object,gint job)2077 object_floating_flag_handler (GObject *object,
2078 gint job)
2079 {
2080 switch (job)
2081 {
2082 gpointer oldvalue;
2083 case +1: /* force floating if possible */
2084 do
2085 oldvalue = g_atomic_pointer_get (&object->qdata);
2086 while (!g_atomic_pointer_compare_and_exchange ((void**) &object->qdata, oldvalue,
2087 (gpointer) ((gsize) oldvalue | OBJECT_FLOATING_FLAG)));
2088 return (gsize) oldvalue & OBJECT_FLOATING_FLAG;
2089 case -1: /* sink if possible */
2090 do
2091 oldvalue = g_atomic_pointer_get (&object->qdata);
2092 while (!g_atomic_pointer_compare_and_exchange ((void**) &object->qdata, oldvalue,
2093 (gpointer) ((gsize) oldvalue & ~(gsize) OBJECT_FLOATING_FLAG)));
2094 return (gsize) oldvalue & OBJECT_FLOATING_FLAG;
2095 default: /* check floating */
2096 return 0 != ((gsize) g_atomic_pointer_get (&object->qdata) & OBJECT_FLOATING_FLAG);
2097 }
2098 }
2099
2100 /**
2101 * g_object_is_floating:
2102 * @object: a #GObject
2103 *
2104 * Checks wether @object has a <link linkend="floating-ref">floating</link>
2105 * reference.
2106 *
2107 * Since: 2.10
2108 *
2109 * Returns: %TRUE if @object has a floating reference
2110 */
2111 gboolean
g_object_is_floating(gpointer _object)2112 g_object_is_floating (gpointer _object)
2113 {
2114 GObject *object = _object;
2115 g_return_val_if_fail (G_IS_OBJECT (object), FALSE);
2116 return floating_flag_handler (object, 0);
2117 }
2118
2119 /**
2120 * g_object_ref_sink:
2121 * @object: a #GObject
2122 *
2123 * Increase the reference count of @object, and possibly remove the
2124 * <link linkend="floating-ref">floating</link> reference, if @object
2125 * has a floating reference.
2126 *
2127 * In other words, if the object is floating, then this call "assumes
2128 * ownership" of the floating reference, converting it to a normal
2129 * reference by clearing the floating flag while leaving the reference
2130 * count unchanged. If the object is not floating, then this call
2131 * adds a new normal reference increasing the reference count by one.
2132 *
2133 * Since: 2.10
2134 *
2135 * Returns: @object
2136 */
2137 gpointer
g_object_ref_sink(gpointer _object)2138 g_object_ref_sink (gpointer _object)
2139 {
2140 GObject *object = _object;
2141 gboolean was_floating;
2142 g_return_val_if_fail (G_IS_OBJECT (object), object);
2143 g_return_val_if_fail (object->ref_count >= 1, object);
2144 g_object_ref (object);
2145 was_floating = floating_flag_handler (object, -1);
2146 if (was_floating)
2147 g_object_unref (object);
2148 return object;
2149 }
2150
2151 /**
2152 * g_object_force_floating:
2153 * @object: a #GObject
2154 *
2155 * This function is intended for #GObject implementations to re-enforce a
2156 * <link linkend="floating-ref">floating</link> object reference.
2157 * Doing this is seldomly required, all
2158 * #GInitiallyUnowned<!-- -->s are created with a floating reference which
2159 * usually just needs to be sunken by calling g_object_ref_sink().
2160 *
2161 * Since: 2.10
2162 */
2163 void
g_object_force_floating(GObject * object)2164 g_object_force_floating (GObject *object)
2165 {
2166 gboolean was_floating;
2167 g_return_if_fail (G_IS_OBJECT (object));
2168 g_return_if_fail (object->ref_count >= 1);
2169
2170 was_floating = floating_flag_handler (object, +1);
2171 }
2172
2173 typedef struct {
2174 GObject *object;
2175 guint n_toggle_refs;
2176 struct {
2177 GToggleNotify notify;
2178 gpointer data;
2179 } toggle_refs[1]; /* flexible array */
2180 } ToggleRefStack;
2181
2182 static void
toggle_refs_notify(GObject * object,gboolean is_last_ref)2183 toggle_refs_notify (GObject *object,
2184 gboolean is_last_ref)
2185 {
2186 ToggleRefStack *tstack = g_datalist_id_get_data (&object->qdata, quark_toggle_refs);
2187
2188 /* Reentrancy here is not as tricky as it seems, because a toggle reference
2189 * will only be notified when there is exactly one of them.
2190 */
2191 g_assert (tstack->n_toggle_refs == 1);
2192 tstack->toggle_refs[0].notify (tstack->toggle_refs[0].data, tstack->object, is_last_ref);
2193 }
2194
2195 /**
2196 * g_object_add_toggle_ref:
2197 * @object: a #GObject
2198 * @notify: a function to call when this reference is the
2199 * last reference to the object, or is no longer
2200 * the last reference.
2201 * @data: data to pass to @notify
2202 *
2203 * Increases the reference count of the object by one and sets a
2204 * callback to be called when all other references to the object are
2205 * dropped, or when this is already the last reference to the object
2206 * and another reference is established.
2207 *
2208 * This functionality is intended for binding @object to a proxy
2209 * object managed by another memory manager. This is done with two
2210 * paired references: the strong reference added by
2211 * g_object_add_toggle_ref() and a reverse reference to the proxy
2212 * object which is either a strong reference or weak reference.
2213 *
2214 * The setup is that when there are no other references to @object,
2215 * only a weak reference is held in the reverse direction from @object
2216 * to the proxy object, but when there are other references held to
2217 * @object, a strong reference is held. The @notify callback is called
2218 * when the reference from @object to the proxy object should be
2219 * <firstterm>toggled</firstterm> from strong to weak (@is_last_ref
2220 * true) or weak to strong (@is_last_ref false).
2221 *
2222 * Since a (normal) reference must be held to the object before
2223 * calling g_object_toggle_ref(), the initial state of the reverse
2224 * link is always strong.
2225 *
2226 * Multiple toggle references may be added to the same gobject,
2227 * however if there are multiple toggle references to an object, none
2228 * of them will ever be notified until all but one are removed. For
2229 * this reason, you should only ever use a toggle reference if there
2230 * is important state in the proxy object.
2231 *
2232 * Since: 2.8
2233 */
2234 void
g_object_add_toggle_ref(GObject * object,GToggleNotify notify,gpointer data)2235 g_object_add_toggle_ref (GObject *object,
2236 GToggleNotify notify,
2237 gpointer data)
2238 {
2239 ToggleRefStack *tstack;
2240 guint i;
2241
2242 g_return_if_fail (G_IS_OBJECT (object));
2243 g_return_if_fail (notify != NULL);
2244 g_return_if_fail (object->ref_count >= 1);
2245
2246 g_object_ref (object);
2247
2248 tstack = g_datalist_id_remove_no_notify (&object->qdata, quark_toggle_refs);
2249 if (tstack)
2250 {
2251 i = tstack->n_toggle_refs++;
2252 /* allocate i = tstate->n_toggle_refs - 1 positions beyond the 1 declared
2253 * in tstate->toggle_refs */
2254 tstack = g_realloc (tstack, sizeof (*tstack) + sizeof (tstack->toggle_refs[0]) * i);
2255 }
2256 else
2257 {
2258 tstack = g_renew (ToggleRefStack, NULL, 1);
2259 tstack->object = object;
2260 tstack->n_toggle_refs = 1;
2261 i = 0;
2262 }
2263
2264 /* Set a flag for fast lookup after adding the first toggle reference */
2265 if (tstack->n_toggle_refs == 1)
2266 g_datalist_set_flags (&object->qdata, OBJECT_HAS_TOGGLE_REF_FLAG);
2267
2268 tstack->toggle_refs[i].notify = notify;
2269 tstack->toggle_refs[i].data = data;
2270 g_datalist_id_set_data_full (&object->qdata, quark_toggle_refs, tstack,
2271 (GDestroyNotify)g_free);
2272 }
2273
2274 /**
2275 * g_object_remove_toggle_ref:
2276 * @object: a #GObject
2277 * @notify: a function to call when this reference is the
2278 * last reference to the object, or is no longer
2279 * the last reference.
2280 * @data: data to pass to @notify
2281 *
2282 * Removes a reference added with g_object_add_toggle_ref(). The
2283 * reference count of the object is decreased by one.
2284 *
2285 * Since: 2.8
2286 */
2287 void
g_object_remove_toggle_ref(GObject * object,GToggleNotify notify,gpointer data)2288 g_object_remove_toggle_ref (GObject *object,
2289 GToggleNotify notify,
2290 gpointer data)
2291 {
2292 ToggleRefStack *tstack;
2293 gboolean found_one = FALSE;
2294
2295 g_return_if_fail (G_IS_OBJECT (object));
2296 g_return_if_fail (notify != NULL);
2297
2298 tstack = g_datalist_id_get_data (&object->qdata, quark_toggle_refs);
2299 if (tstack)
2300 {
2301 guint i;
2302
2303 for (i = 0; i < tstack->n_toggle_refs; i++)
2304 if (tstack->toggle_refs[i].notify == notify &&
2305 tstack->toggle_refs[i].data == data)
2306 {
2307 found_one = TRUE;
2308 tstack->n_toggle_refs -= 1;
2309 if (i != tstack->n_toggle_refs)
2310 tstack->toggle_refs[i] = tstack->toggle_refs[tstack->n_toggle_refs];
2311
2312 if (tstack->n_toggle_refs == 0)
2313 g_datalist_unset_flags (&object->qdata, OBJECT_HAS_TOGGLE_REF_FLAG);
2314
2315 g_object_unref (object);
2316
2317 break;
2318 }
2319 }
2320
2321 if (!found_one)
2322 g_warning ("%s: couldn't find toggle ref %p(%p)", G_STRFUNC, notify, data);
2323 }
2324
2325 /**
2326 * g_object_ref:
2327 * @object: a #GObject
2328 *
2329 * Increases the reference count of @object.
2330 *
2331 * Returns: the same @object
2332 */
2333 gpointer
g_object_ref(gpointer _object)2334 g_object_ref (gpointer _object)
2335 {
2336 GObject *object = _object;
2337 gint old_val;
2338
2339 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
2340 g_return_val_if_fail (object->ref_count > 0, NULL);
2341
2342 #ifdef G_ENABLE_DEBUG
2343 if (g_trap_object_ref == object)
2344 G_BREAKPOINT ();
2345 #endif /* G_ENABLE_DEBUG */
2346
2347
2348 old_val = g_atomic_int_exchange_and_add ((int *)&object->ref_count, 1);
2349
2350 if (old_val == 1 && OBJECT_HAS_TOGGLE_REF (object))
2351 toggle_refs_notify (object, FALSE);
2352
2353 return object;
2354 }
2355
2356 /**
2357 * g_object_unref:
2358 * @object: a #GObject
2359 *
2360 * Decreases the reference count of @object. When its reference count
2361 * drops to 0, the object is finalized (i.e. its memory is freed).
2362 */
2363 void
g_object_unref(gpointer _object)2364 g_object_unref (gpointer _object)
2365 {
2366 GObject *object = _object;
2367 gint old_ref;
2368 gboolean is_zero;
2369
2370 g_return_if_fail (G_IS_OBJECT (object));
2371 g_return_if_fail (object->ref_count > 0);
2372
2373 #ifdef G_ENABLE_DEBUG
2374 if (g_trap_object_ref == object)
2375 G_BREAKPOINT ();
2376 #endif /* G_ENABLE_DEBUG */
2377
2378 /* here we want to atomically do: if (ref_count>1) { ref_count--; return; } */
2379 retry_atomic_decrement1:
2380 old_ref = g_atomic_int_get (&object->ref_count);
2381 if (old_ref > 1)
2382 {
2383 if (!g_atomic_int_compare_and_exchange ((int *)&object->ref_count, old_ref, old_ref - 1))
2384 goto retry_atomic_decrement1;
2385
2386 /* if we went from 2->1 we need to notify toggle refs if any */
2387 if (old_ref == 2 && OBJECT_HAS_TOGGLE_REF (object))
2388 toggle_refs_notify (object, TRUE);
2389 }
2390 else
2391 {
2392 /* we are about tp remove the last reference */
2393 G_OBJECT_GET_CLASS (object)->dispose (object);
2394
2395 /* may have been re-referenced meanwhile */
2396 retry_atomic_decrement2:
2397 old_ref = g_atomic_int_get ((int *)&object->ref_count);
2398 if (old_ref > 1)
2399 {
2400 if (!g_atomic_int_compare_and_exchange ((int *)&object->ref_count, old_ref, old_ref - 1))
2401 goto retry_atomic_decrement2;
2402
2403 /* if we went from 2->1 we need to notify toggle refs if any */
2404 if (old_ref == 2 && OBJECT_HAS_TOGGLE_REF (object))
2405 toggle_refs_notify (object, TRUE);
2406
2407 return;
2408 }
2409
2410 /* we are still in the process of taking away the last ref */
2411 g_datalist_id_set_data (&object->qdata, quark_closure_array, NULL);
2412 g_signal_handlers_destroy (object);
2413 g_datalist_id_set_data (&object->qdata, quark_weak_refs, NULL);
2414
2415 /* decrement the last reference */
2416 is_zero = g_atomic_int_dec_and_test ((int *)&object->ref_count);
2417
2418 /* may have been re-referenced meanwhile */
2419 if (G_LIKELY (is_zero))
2420 {
2421 G_OBJECT_GET_CLASS (object)->finalize (object);
2422 #ifdef G_ENABLE_DEBUG
2423 IF_DEBUG (OBJECTS)
2424 {
2425 /* catch objects not chaining finalize handlers */
2426 G_LOCK (debug_objects);
2427 g_assert (g_hash_table_lookup (debug_objects_ht, object) == NULL);
2428 G_UNLOCK (debug_objects);
2429 }
2430 #endif /* G_ENABLE_DEBUG */
2431 g_type_free_instance ((GTypeInstance*) object);
2432 }
2433 }
2434 }
2435
2436 /**
2437 * g_object_get_qdata:
2438 * @object: The GObject to get a stored user data pointer from
2439 * @quark: A #GQuark, naming the user data pointer
2440 *
2441 * This function gets back user data pointers stored via
2442 * g_object_set_qdata().
2443 *
2444 * Returns: The user data pointer set, or %NULL
2445 */
2446 gpointer
g_object_get_qdata(GObject * object,GQuark quark)2447 g_object_get_qdata (GObject *object,
2448 GQuark quark)
2449 {
2450 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
2451
2452 return quark ? g_datalist_id_get_data (&object->qdata, quark) : NULL;
2453 }
2454
2455 /**
2456 * g_object_set_qdata:
2457 * @object: The GObject to set store a user data pointer
2458 * @quark: A #GQuark, naming the user data pointer
2459 * @data: An opaque user data pointer
2460 *
2461 * This sets an opaque, named pointer on an object.
2462 * The name is specified through a #GQuark (retrived e.g. via
2463 * g_quark_from_static_string()), and the pointer
2464 * can be gotten back from the @object with g_object_get_qdata()
2465 * until the @object is finalized.
2466 * Setting a previously set user data pointer, overrides (frees)
2467 * the old pointer set, using #NULL as pointer essentially
2468 * removes the data stored.
2469 */
2470 void
g_object_set_qdata(GObject * object,GQuark quark,gpointer data)2471 g_object_set_qdata (GObject *object,
2472 GQuark quark,
2473 gpointer data)
2474 {
2475 g_return_if_fail (G_IS_OBJECT (object));
2476 g_return_if_fail (quark > 0);
2477
2478 g_datalist_id_set_data (&object->qdata, quark, data);
2479 }
2480
2481 /**
2482 * g_object_set_qdata_full:
2483 * @object: The GObject to set store a user data pointer
2484 * @quark: A #GQuark, naming the user data pointer
2485 * @data: An opaque user data pointer
2486 * @destroy: Function to invoke with @data as argument, when @data
2487 * needs to be freed
2488 *
2489 * This function works like g_object_set_qdata(), but in addition,
2490 * a void (*destroy) (gpointer) function may be specified which is
2491 * called with @data as argument when the @object is finalized, or
2492 * the data is being overwritten by a call to g_object_set_qdata()
2493 * with the same @quark.
2494 */
2495 void
g_object_set_qdata_full(GObject * object,GQuark quark,gpointer data,GDestroyNotify destroy)2496 g_object_set_qdata_full (GObject *object,
2497 GQuark quark,
2498 gpointer data,
2499 GDestroyNotify destroy)
2500 {
2501 g_return_if_fail (G_IS_OBJECT (object));
2502 g_return_if_fail (quark > 0);
2503
2504 g_datalist_id_set_data_full (&object->qdata, quark, data,
2505 data ? destroy : (GDestroyNotify) NULL);
2506 }
2507
2508 /**
2509 * g_object_steal_qdata:
2510 * @object: The GObject to get a stored user data pointer from
2511 * @quark: A #GQuark, naming the user data pointer
2512 *
2513 * This function gets back user data pointers stored via
2514 * g_object_set_qdata() and removes the @data from object
2515 * without invoking its destroy() function (if any was
2516 * set).
2517 * Usually, calling this function is only required to update
2518 * user data pointers with a destroy notifier, for example:
2519 * |[
2520 * void
2521 * object_add_to_user_list (GObject *object,
2522 * const gchar *new_string)
2523 * {
2524 * // the quark, naming the object data
2525 * GQuark quark_string_list = g_quark_from_static_string ("my-string-list");
2526 * // retrive the old string list
2527 * GList *list = g_object_steal_qdata (object, quark_string_list);
2528 *
2529 * // prepend new string
2530 * list = g_list_prepend (list, g_strdup (new_string));
2531 * // this changed 'list', so we need to set it again
2532 * g_object_set_qdata_full (object, quark_string_list, list, free_string_list);
2533 * }
2534 * static void
2535 * free_string_list (gpointer data)
2536 * {
2537 * GList *node, *list = data;
2538 *
2539 * for (node = list; node; node = node->next)
2540 * g_free (node->data);
2541 * g_list_free (list);
2542 * }
2543 * ]|
2544 * Using g_object_get_qdata() in the above example, instead of
2545 * g_object_steal_qdata() would have left the destroy function set,
2546 * and thus the partial string list would have been freed upon
2547 * g_object_set_qdata_full().
2548 *
2549 * Returns: The user data pointer set, or %NULL
2550 */
2551 gpointer
g_object_steal_qdata(GObject * object,GQuark quark)2552 g_object_steal_qdata (GObject *object,
2553 GQuark quark)
2554 {
2555 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
2556 g_return_val_if_fail (quark > 0, NULL);
2557
2558 return g_datalist_id_remove_no_notify (&object->qdata, quark);
2559 }
2560
2561 /**
2562 * g_object_get_data:
2563 * @object: #GObject containing the associations
2564 * @key: name of the key for that association
2565 *
2566 * Gets a named field from the objects table of associations (see g_object_set_data()).
2567 *
2568 * Returns: the data if found, or %NULL if no such data exists.
2569 */
2570 gpointer
g_object_get_data(GObject * object,const gchar * key)2571 g_object_get_data (GObject *object,
2572 const gchar *key)
2573 {
2574 GQuark quark;
2575
2576 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
2577 g_return_val_if_fail (key != NULL, NULL);
2578
2579 quark = g_quark_try_string (key);
2580
2581 return quark ? g_datalist_id_get_data (&object->qdata, quark) : NULL;
2582 }
2583
2584 /**
2585 * g_object_set_data:
2586 * @object: #GObject containing the associations.
2587 * @key: name of the key
2588 * @data: data to associate with that key
2589 *
2590 * Each object carries around a table of associations from
2591 * strings to pointers. This function lets you set an association.
2592 *
2593 * If the object already had an association with that name,
2594 * the old association will be destroyed.
2595 */
2596 void
g_object_set_data(GObject * object,const gchar * key,gpointer data)2597 g_object_set_data (GObject *object,
2598 const gchar *key,
2599 gpointer data)
2600 {
2601 g_return_if_fail (G_IS_OBJECT (object));
2602 g_return_if_fail (key != NULL);
2603
2604 g_datalist_id_set_data (&object->qdata, g_quark_from_string (key), data);
2605 }
2606
2607 /**
2608 * g_object_set_data_full:
2609 * @object: #GObject containing the associations
2610 * @key: name of the key
2611 * @data: data to associate with that key
2612 * @destroy: function to call when the association is destroyed
2613 *
2614 * Like g_object_set_data() except it adds notification
2615 * for when the association is destroyed, either by setting it
2616 * to a different value or when the object is destroyed.
2617 *
2618 * Note that the @destroy callback is not called if @data is %NULL.
2619 */
2620 void
g_object_set_data_full(GObject * object,const gchar * key,gpointer data,GDestroyNotify destroy)2621 g_object_set_data_full (GObject *object,
2622 const gchar *key,
2623 gpointer data,
2624 GDestroyNotify destroy)
2625 {
2626 g_return_if_fail (G_IS_OBJECT (object));
2627 g_return_if_fail (key != NULL);
2628
2629 g_datalist_id_set_data_full (&object->qdata, g_quark_from_string (key), data,
2630 data ? destroy : (GDestroyNotify) NULL);
2631 }
2632
2633 /**
2634 * g_object_steal_data:
2635 * @object: #GObject containing the associations
2636 * @key: name of the key
2637 *
2638 * Remove a specified datum from the object's data associations,
2639 * without invoking the association's destroy handler.
2640 *
2641 * Returns: the data if found, or %NULL if no such data exists.
2642 */
2643 gpointer
g_object_steal_data(GObject * object,const gchar * key)2644 g_object_steal_data (GObject *object,
2645 const gchar *key)
2646 {
2647 GQuark quark;
2648
2649 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
2650 g_return_val_if_fail (key != NULL, NULL);
2651
2652 quark = g_quark_try_string (key);
2653
2654 return quark ? g_datalist_id_remove_no_notify (&object->qdata, quark) : NULL;
2655 }
2656
2657 static void
g_value_object_init(GValue * value)2658 g_value_object_init (GValue *value)
2659 {
2660 value->data[0].v_pointer = NULL;
2661 }
2662
2663 static void
g_value_object_free_value(GValue * value)2664 g_value_object_free_value (GValue *value)
2665 {
2666 if (value->data[0].v_pointer)
2667 g_object_unref (value->data[0].v_pointer);
2668 }
2669
2670 static void
g_value_object_copy_value(const GValue * src_value,GValue * dest_value)2671 g_value_object_copy_value (const GValue *src_value,
2672 GValue *dest_value)
2673 {
2674 if (src_value->data[0].v_pointer)
2675 dest_value->data[0].v_pointer = g_object_ref (src_value->data[0].v_pointer);
2676 else
2677 dest_value->data[0].v_pointer = NULL;
2678 }
2679
2680 static void
g_value_object_transform_value(const GValue * src_value,GValue * dest_value)2681 g_value_object_transform_value (const GValue *src_value,
2682 GValue *dest_value)
2683 {
2684 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)))
2685 dest_value->data[0].v_pointer = g_object_ref (src_value->data[0].v_pointer);
2686 else
2687 dest_value->data[0].v_pointer = NULL;
2688 }
2689
2690 static gpointer
g_value_object_peek_pointer(const GValue * value)2691 g_value_object_peek_pointer (const GValue *value)
2692 {
2693 return value->data[0].v_pointer;
2694 }
2695
2696 static gchar*
g_value_object_collect_value(GValue * value,guint n_collect_values,GTypeCValue * collect_values,guint collect_flags)2697 g_value_object_collect_value (GValue *value,
2698 guint n_collect_values,
2699 GTypeCValue *collect_values,
2700 guint collect_flags)
2701 {
2702 if (collect_values[0].v_pointer)
2703 {
2704 GObject *object = collect_values[0].v_pointer;
2705
2706 if (object->g_type_instance.g_class == NULL)
2707 return g_strconcat ("invalid unclassed object pointer for value type `",
2708 G_VALUE_TYPE_NAME (value),
2709 "'",
2710 NULL);
2711 else if (!g_value_type_compatible (G_OBJECT_TYPE (object), G_VALUE_TYPE (value)))
2712 return g_strconcat ("invalid object type `",
2713 G_OBJECT_TYPE_NAME (object),
2714 "' for value type `",
2715 G_VALUE_TYPE_NAME (value),
2716 "'",
2717 NULL);
2718 /* never honour G_VALUE_NOCOPY_CONTENTS for ref-counted types */
2719 value->data[0].v_pointer = g_object_ref (object);
2720 }
2721 else
2722 value->data[0].v_pointer = NULL;
2723
2724 return NULL;
2725 }
2726
2727 static gchar*
g_value_object_lcopy_value(const GValue * value,guint n_collect_values,GTypeCValue * collect_values,guint collect_flags)2728 g_value_object_lcopy_value (const GValue *value,
2729 guint n_collect_values,
2730 GTypeCValue *collect_values,
2731 guint collect_flags)
2732 {
2733 GObject **object_p = collect_values[0].v_pointer;
2734
2735 if (!object_p)
2736 return g_strdup_printf ("value location for `%s' passed as NULL", G_VALUE_TYPE_NAME (value));
2737
2738 if (!value->data[0].v_pointer)
2739 *object_p = NULL;
2740 else if (collect_flags & G_VALUE_NOCOPY_CONTENTS)
2741 *object_p = value->data[0].v_pointer;
2742 else
2743 *object_p = g_object_ref (value->data[0].v_pointer);
2744
2745 return NULL;
2746 }
2747
2748 /**
2749 * g_value_set_object:
2750 * @value: a valid #GValue of %G_TYPE_OBJECT derived type
2751 * @v_object: object value to be set
2752 *
2753 * Set the contents of a %G_TYPE_OBJECT derived #GValue to @v_object.
2754 *
2755 * g_value_set_object() increases the reference count of @v_object
2756 * (the #GValue holds a reference to @v_object). If you do not wish
2757 * to increase the reference count of the object (i.e. you wish to
2758 * pass your current reference to the #GValue because you no longer
2759 * need it), use g_value_take_object() instead.
2760 *
2761 * It is important that your #GValue holds a reference to @v_object (either its
2762 * own, or one it has taken) to ensure that the object won't be destroyed while
2763 * the #GValue still exists).
2764 */
2765 void
g_value_set_object(GValue * value,gpointer v_object)2766 g_value_set_object (GValue *value,
2767 gpointer v_object)
2768 {
2769 GObject *old;
2770
2771 g_return_if_fail (G_VALUE_HOLDS_OBJECT (value));
2772
2773 old = value->data[0].v_pointer;
2774
2775 if (v_object)
2776 {
2777 g_return_if_fail (G_IS_OBJECT (v_object));
2778 g_return_if_fail (g_value_type_compatible (G_OBJECT_TYPE (v_object), G_VALUE_TYPE (value)));
2779
2780 value->data[0].v_pointer = v_object;
2781 g_object_ref (value->data[0].v_pointer);
2782 }
2783 else
2784 value->data[0].v_pointer = NULL;
2785
2786 if (old)
2787 g_object_unref (old);
2788 }
2789
2790 /**
2791 * g_value_set_object_take_ownership:
2792 * @value: a valid #GValue of %G_TYPE_OBJECT derived type
2793 * @v_object: object value to be set
2794 *
2795 * This is an internal function introduced mainly for C marshallers.
2796 *
2797 * Deprecated: 2.4: Use g_value_take_object() instead.
2798 */
2799 void
g_value_set_object_take_ownership(GValue * value,gpointer v_object)2800 g_value_set_object_take_ownership (GValue *value,
2801 gpointer v_object)
2802 {
2803 g_value_take_object (value, v_object);
2804 }
2805
2806 /**
2807 * g_value_take_object:
2808 * @value: a valid #GValue of %G_TYPE_OBJECT derived type
2809 * @v_object: object value to be set
2810 *
2811 * Sets the contents of a %G_TYPE_OBJECT derived #GValue to @v_object
2812 * and takes over the ownership of the callers reference to @v_object;
2813 * the caller doesn't have to unref it any more (i.e. the reference
2814 * count of the object is not increased).
2815 *
2816 * If you want the #GValue to hold its own reference to @v_object, use
2817 * g_value_set_object() instead.
2818 *
2819 * Since: 2.4
2820 */
2821 void
g_value_take_object(GValue * value,gpointer v_object)2822 g_value_take_object (GValue *value,
2823 gpointer v_object)
2824 {
2825 g_return_if_fail (G_VALUE_HOLDS_OBJECT (value));
2826
2827 if (value->data[0].v_pointer)
2828 {
2829 g_object_unref (value->data[0].v_pointer);
2830 value->data[0].v_pointer = NULL;
2831 }
2832
2833 if (v_object)
2834 {
2835 g_return_if_fail (G_IS_OBJECT (v_object));
2836 g_return_if_fail (g_value_type_compatible (G_OBJECT_TYPE (v_object), G_VALUE_TYPE (value)));
2837
2838 value->data[0].v_pointer = v_object; /* we take over the reference count */
2839 }
2840 }
2841
2842 /**
2843 * g_value_get_object:
2844 * @value: a valid #GValue of %G_TYPE_OBJECT derived type
2845 *
2846 * Get the contents of a %G_TYPE_OBJECT derived #GValue.
2847 *
2848 * Returns: object contents of @value
2849 */
2850 gpointer
g_value_get_object(const GValue * value)2851 g_value_get_object (const GValue *value)
2852 {
2853 g_return_val_if_fail (G_VALUE_HOLDS_OBJECT (value), NULL);
2854
2855 return value->data[0].v_pointer;
2856 }
2857
2858 /**
2859 * g_value_dup_object:
2860 * @value: a valid #GValue whose type is derived from %G_TYPE_OBJECT
2861 *
2862 * Get the contents of a %G_TYPE_OBJECT derived #GValue, increasing
2863 * its reference count.
2864 *
2865 * Returns: object content of @value, should be unreferenced when no
2866 * longer needed.
2867 */
2868 gpointer
g_value_dup_object(const GValue * value)2869 g_value_dup_object (const GValue *value)
2870 {
2871 g_return_val_if_fail (G_VALUE_HOLDS_OBJECT (value), NULL);
2872
2873 return value->data[0].v_pointer ? g_object_ref (value->data[0].v_pointer) : NULL;
2874 }
2875
2876 /**
2877 * g_signal_connect_object:
2878 * @instance: the instance to connect to.
2879 * @detailed_signal: a string of the form "signal-name::detail".
2880 * @c_handler: the #GCallback to connect.
2881 * @gobject: the object to pass as data to @c_handler.
2882 * @connect_flags: a combination of #GConnnectFlags.
2883 *
2884 * This is similar to g_signal_connect_data(), but uses a closure which
2885 * ensures that the @gobject stays alive during the call to @c_handler
2886 * by temporarily adding a reference count to @gobject.
2887 *
2888 * Note that there is a bug in GObject that makes this function
2889 * much less useful than it might seem otherwise. Once @gobject is
2890 * disposed, the callback will no longer be called, but, the signal
2891 * handler is <emphasis>not</emphasis> currently disconnected. If the
2892 * @instance is itself being freed at the same time than this doesn't
2893 * matter, since the signal will automatically be removed, but
2894 * if @instance persists, then the signal handler will leak. You
2895 * should not remove the signal yourself because in a future versions of
2896 * GObject, the handler <emphasis>will</emphasis> automatically
2897 * be disconnected.
2898 *
2899 * It's possible to work around this problem in a way that will
2900 * continue to work with future versions of GObject by checking
2901 * that the signal handler is still connected before disconnected it:
2902 * <informalexample><programlisting>
2903 * if (g_signal_handler_is_connected (instance, id))
2904 * g_signal_handler_disconnect (instance, id);
2905 * </programlisting></informalexample>
2906 *
2907 * Returns: the handler id.
2908 */
2909 gulong
g_signal_connect_object(gpointer instance,const gchar * detailed_signal,GCallback c_handler,gpointer gobject,GConnectFlags connect_flags)2910 g_signal_connect_object (gpointer instance,
2911 const gchar *detailed_signal,
2912 GCallback c_handler,
2913 gpointer gobject,
2914 GConnectFlags connect_flags)
2915 {
2916 g_return_val_if_fail (G_TYPE_CHECK_INSTANCE (instance), 0);
2917 g_return_val_if_fail (detailed_signal != NULL, 0);
2918 g_return_val_if_fail (c_handler != NULL, 0);
2919
2920 if (gobject)
2921 {
2922 GClosure *closure;
2923
2924 g_return_val_if_fail (G_IS_OBJECT (gobject), 0);
2925
2926 closure = ((connect_flags & G_CONNECT_SWAPPED) ? g_cclosure_new_object_swap : g_cclosure_new_object) (c_handler, gobject);
2927
2928 return g_signal_connect_closure (instance, detailed_signal, closure, connect_flags & G_CONNECT_AFTER);
2929 }
2930 else
2931 return g_signal_connect_data (instance, detailed_signal, c_handler, NULL, NULL, connect_flags);
2932 }
2933
2934 typedef struct {
2935 GObject *object;
2936 guint n_closures;
2937 GClosure *closures[1]; /* flexible array */
2938 } CArray;
2939 /* don't change this structure without supplying an accessor for
2940 * watched closures, e.g.:
2941 * GSList* g_object_list_watched_closures (GObject *object)
2942 * {
2943 * CArray *carray;
2944 * g_return_val_if_fail (G_IS_OBJECT (object), NULL);
2945 * carray = g_object_get_data (object, "GObject-closure-array");
2946 * if (carray)
2947 * {
2948 * GSList *slist = NULL;
2949 * guint i;
2950 * for (i = 0; i < carray->n_closures; i++)
2951 * slist = g_slist_prepend (slist, carray->closures[i]);
2952 * return slist;
2953 * }
2954 * return NULL;
2955 * }
2956 */
2957
2958 static void
object_remove_closure(gpointer data,GClosure * closure)2959 object_remove_closure (gpointer data,
2960 GClosure *closure)
2961 {
2962 GObject *object = data;
2963 CArray *carray = g_object_get_qdata (object, quark_closure_array);
2964 guint i;
2965
2966 for (i = 0; i < carray->n_closures; i++)
2967 if (carray->closures[i] == closure)
2968 {
2969 carray->n_closures--;
2970 if (i < carray->n_closures)
2971 carray->closures[i] = carray->closures[carray->n_closures];
2972 return;
2973 }
2974 g_assert_not_reached ();
2975 }
2976
2977 static void
destroy_closure_array(gpointer data)2978 destroy_closure_array (gpointer data)
2979 {
2980 CArray *carray = data;
2981 GObject *object = carray->object;
2982 guint i, n = carray->n_closures;
2983
2984 for (i = 0; i < n; i++)
2985 {
2986 GClosure *closure = carray->closures[i];
2987
2988 /* removing object_remove_closure() upfront is probably faster than
2989 * letting it fiddle with quark_closure_array which is empty anyways
2990 */
2991 g_closure_remove_invalidate_notifier (closure, object, object_remove_closure);
2992 g_closure_invalidate (closure);
2993 }
2994 g_free (carray);
2995 }
2996
2997 /**
2998 * g_object_watch_closure:
2999 * @object: GObject restricting lifetime of @closure
3000 * @closure: GClosure to watch
3001 *
3002 * This function essentially limits the life time of the @closure to
3003 * the life time of the object. That is, when the object is finalized,
3004 * the @closure is invalidated by calling g_closure_invalidate() on
3005 * it, in order to prevent invocations of the closure with a finalized
3006 * (nonexisting) object. Also, g_object_ref() and g_object_unref() are
3007 * added as marshal guards to the @closure, to ensure that an extra
3008 * reference count is held on @object during invocation of the
3009 * @closure. Usually, this function will be called on closures that
3010 * use this @object as closure data.
3011 */
3012 void
g_object_watch_closure(GObject * object,GClosure * closure)3013 g_object_watch_closure (GObject *object,
3014 GClosure *closure)
3015 {
3016 CArray *carray;
3017 guint i;
3018
3019 g_return_if_fail (G_IS_OBJECT (object));
3020 g_return_if_fail (closure != NULL);
3021 g_return_if_fail (closure->is_invalid == FALSE);
3022 g_return_if_fail (closure->in_marshal == FALSE);
3023 g_return_if_fail (object->ref_count > 0); /* this doesn't work on finalizing objects */
3024
3025 g_closure_add_invalidate_notifier (closure, object, object_remove_closure);
3026 g_closure_add_marshal_guards (closure,
3027 object, (GClosureNotify) g_object_ref,
3028 object, (GClosureNotify) g_object_unref);
3029 carray = g_datalist_id_remove_no_notify (&object->qdata, quark_closure_array);
3030 if (!carray)
3031 {
3032 carray = g_renew (CArray, NULL, 1);
3033 carray->object = object;
3034 carray->n_closures = 1;
3035 i = 0;
3036 }
3037 else
3038 {
3039 i = carray->n_closures++;
3040 carray = g_realloc (carray, sizeof (*carray) + sizeof (carray->closures[0]) * i);
3041 }
3042 carray->closures[i] = closure;
3043 g_datalist_id_set_data_full (&object->qdata, quark_closure_array, carray, destroy_closure_array);
3044 }
3045
3046 /**
3047 * g_closure_new_object:
3048 * @sizeof_closure: the size of the structure to allocate, must be at least
3049 * <literal>sizeof (GClosure)</literal>
3050 * @object: a #GObject pointer to store in the @data field of the newly
3051 * allocated #GClosure
3052 *
3053 * A variant of g_closure_new_simple() which stores @object in the
3054 * @data field of the closure and calls g_object_watch_closure() on
3055 * @object and the created closure. This function is mainly useful
3056 * when implementing new types of closures.
3057 *
3058 * Returns: a newly allocated #GClosure
3059 */
3060 GClosure*
g_closure_new_object(guint sizeof_closure,GObject * object)3061 g_closure_new_object (guint sizeof_closure,
3062 GObject *object)
3063 {
3064 GClosure *closure;
3065
3066 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
3067 g_return_val_if_fail (object->ref_count > 0, NULL); /* this doesn't work on finalizing objects */
3068
3069 closure = g_closure_new_simple (sizeof_closure, object);
3070 g_object_watch_closure (object, closure);
3071
3072 return closure;
3073 }
3074
3075 /**
3076 * g_cclosure_new_object:
3077 * @callback_func: the function to invoke
3078 * @object: a #GObject pointer to pass to @callback_func
3079 *
3080 * A variant of g_cclosure_new() which uses @object as @user_data and
3081 * calls g_object_watch_closure() on @object and the created
3082 * closure. This function is useful when you have a callback closely
3083 * associated with a #GObject, and want the callback to no longer run
3084 * after the object is is freed.
3085 *
3086 * Returns: a new #GCClosure
3087 */
3088 GClosure*
g_cclosure_new_object(GCallback callback_func,GObject * object)3089 g_cclosure_new_object (GCallback callback_func,
3090 GObject *object)
3091 {
3092 GClosure *closure;
3093
3094 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
3095 g_return_val_if_fail (object->ref_count > 0, NULL); /* this doesn't work on finalizing objects */
3096 g_return_val_if_fail (callback_func != NULL, NULL);
3097
3098 closure = g_cclosure_new (callback_func, object, NULL);
3099 g_object_watch_closure (object, closure);
3100
3101 return closure;
3102 }
3103
3104 /**
3105 * g_cclosure_new_object_swap:
3106 * @callback_func: the function to invoke
3107 * @object: a #GObject pointer to pass to @callback_func
3108 *
3109 * A variant of g_cclosure_new_swap() which uses @object as @user_data
3110 * and calls g_object_watch_closure() on @object and the created
3111 * closure. This function is useful when you have a callback closely
3112 * associated with a #GObject, and want the callback to no longer run
3113 * after the object is is freed.
3114 *
3115 * Returns: a new #GCClosure
3116 */
3117 GClosure*
g_cclosure_new_object_swap(GCallback callback_func,GObject * object)3118 g_cclosure_new_object_swap (GCallback callback_func,
3119 GObject *object)
3120 {
3121 GClosure *closure;
3122
3123 g_return_val_if_fail (G_IS_OBJECT (object), NULL);
3124 g_return_val_if_fail (object->ref_count > 0, NULL); /* this doesn't work on finalizing objects */
3125 g_return_val_if_fail (callback_func != NULL, NULL);
3126
3127 closure = g_cclosure_new_swap (callback_func, object, NULL);
3128 g_object_watch_closure (object, closure);
3129
3130 return closure;
3131 }
3132
3133 gsize
g_object_compat_control(gsize what,gpointer data)3134 g_object_compat_control (gsize what,
3135 gpointer data)
3136 {
3137 switch (what)
3138 {
3139 gpointer *pp;
3140 case 1: /* floating base type */
3141 return G_TYPE_INITIALLY_UNOWNED;
3142 case 2: /* FIXME: remove this once GLib/Gtk+ break ABI again */
3143 floating_flag_handler = (guint(*)(GObject*,gint)) data;
3144 return 1;
3145 case 3: /* FIXME: remove this once GLib/Gtk+ break ABI again */
3146 pp = data;
3147 *pp = floating_flag_handler;
3148 return 1;
3149 default:
3150 return 0;
3151 }
3152 }
3153
3154 G_DEFINE_TYPE (GInitiallyUnowned, g_initially_unowned, G_TYPE_OBJECT);
3155
3156 static void
g_initially_unowned_init(GInitiallyUnowned * object)3157 g_initially_unowned_init (GInitiallyUnowned *object)
3158 {
3159 g_object_force_floating (object);
3160 }
3161
3162 static void
g_initially_unowned_class_init(GInitiallyUnownedClass * klass)3163 g_initially_unowned_class_init (GInitiallyUnownedClass *klass)
3164 {
3165 }
3166
3167 #define __G_OBJECT_C__
3168 #include "gobjectaliasdef.c"
3169