/* GObject - GLib Type, Object, Parameter and Signal Library * Copyright (C) 1998-1999, 2000-2001 Tim Janik and Red Hat, Inc. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General * Public License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place, Suite 330, * Boston, MA 02111-1307, USA. */ /* * MT safe with regards to reference counting. */ #include "config.h" #include #include #include "gobject.h" #include "gtype-private.h" #include "gvaluecollector.h" #include "gsignal.h" #include "gparamspecs.h" #include "gvaluetypes.h" #include "gobject_trace.h" #include "gconstructor.h" /** * SECTION:objects * @title: GObject * @short_description: The base object type * @see_also: #GParamSpecObject, g_param_spec_object() * * GObject is the fundamental type providing the common attributes and * methods for all object types in GTK+, Pango and other libraries * based on GObject. The GObject class provides methods for object * construction and destruction, property access methods, and signal * support. Signals are described in detail in . * * * GInitiallyUnowned is derived from GObject. The only difference between * the two is that the initial reference of a GInitiallyUnowned is flagged * as a floating reference. * This means that it is not specifically claimed to be "owned" by * any code portion. The main motivation for providing floating references is * C convenience. In particular, it allows code to be written as: * |[ * container = create_container (); * container_add_child (container, create_child()); * ]| * If container_add_child() will g_object_ref_sink() the * passed in child, no reference of the newly created child is leaked. * Without floating references, container_add_child() * can only g_object_ref() the new child, so to implement this code without * reference leaks, it would have to be written as: * |[ * Child *child; * container = create_container (); * child = create_child (); * container_add_child (container, child); * g_object_unref (child); * ]| * The floating reference can be converted into * an ordinary reference by calling g_object_ref_sink(). * For already sunken objects (objects that don't have a floating reference * anymore), g_object_ref_sink() is equivalent to g_object_ref() and returns * a new reference. * Since floating references are useful almost exclusively for C convenience, * language bindings that provide automated reference and memory ownership * maintenance (such as smart pointers or garbage collection) should not * expose floating references in their API. * * * Some object implementations may need to save an objects floating state * across certain code portions (an example is #GtkMenu), to achieve this, * the following sequence can be used: * * |[ * /* save floating state */ * gboolean was_floating = g_object_is_floating (object); * g_object_ref_sink (object); * /* protected code portion */ * ...; * /* restore floating state */ * if (was_floating) * g_object_force_floating (object); * g_object_unref (object); /* release previously acquired reference */ * ]| */ /* --- macros --- */ #define PARAM_SPEC_PARAM_ID(pspec) ((pspec)->param_id) #define PARAM_SPEC_SET_PARAM_ID(pspec, id) ((pspec)->param_id = (id)) #define OBJECT_HAS_TOGGLE_REF_FLAG 0x1 #define OBJECT_HAS_TOGGLE_REF(object) \ ((g_datalist_get_flags (&(object)->qdata) & OBJECT_HAS_TOGGLE_REF_FLAG) != 0) #define OBJECT_FLOATING_FLAG 0x2 #define CLASS_HAS_PROPS_FLAG 0x1 #define CLASS_HAS_PROPS(class) \ ((class)->flags & CLASS_HAS_PROPS_FLAG) #define CLASS_HAS_CUSTOM_CONSTRUCTOR(class) \ ((class)->constructor != g_object_constructor) #define CLASS_HAS_CUSTOM_CONSTRUCTED(class) \ ((class)->constructed != g_object_constructed) #define CLASS_HAS_DERIVED_CLASS_FLAG 0x2 #define CLASS_HAS_DERIVED_CLASS(class) \ ((class)->flags & CLASS_HAS_DERIVED_CLASS_FLAG) /* --- signals --- */ enum { NOTIFY, LAST_SIGNAL }; /* --- properties --- */ enum { PROP_NONE }; /* --- prototypes --- */ static void g_object_base_class_init (GObjectClass *class); static void g_object_base_class_finalize (GObjectClass *class); static void g_object_do_class_init (GObjectClass *class); static void g_object_init (GObject *object, GObjectClass *class); static GObject* g_object_constructor (GType type, guint n_construct_properties, GObjectConstructParam *construct_params); static void g_object_constructed (GObject *object); static void g_object_real_dispose (GObject *object); static void g_object_finalize (GObject *object); static void g_object_do_set_property (GObject *object, guint property_id, const GValue *value, GParamSpec *pspec); static void g_object_do_get_property (GObject *object, guint property_id, GValue *value, GParamSpec *pspec); static void g_value_object_init (GValue *value); static void g_value_object_free_value (GValue *value); static void g_value_object_copy_value (const GValue *src_value, GValue *dest_value); static void g_value_object_transform_value (const GValue *src_value, GValue *dest_value); static gpointer g_value_object_peek_pointer (const GValue *value); static gchar* g_value_object_collect_value (GValue *value, guint n_collect_values, GTypeCValue *collect_values, guint collect_flags); static gchar* g_value_object_lcopy_value (const GValue *value, guint n_collect_values, GTypeCValue *collect_values, guint collect_flags); static void g_object_dispatch_properties_changed (GObject *object, guint n_pspecs, GParamSpec **pspecs); static guint object_floating_flag_handler (GObject *object, gint job); static void object_interface_check_properties (gpointer func_data, gpointer g_iface); /* --- typedefs --- */ typedef struct _GObjectNotifyQueue GObjectNotifyQueue; struct _GObjectNotifyQueue { GSList *pspecs; guint16 n_pspecs; guint16 freeze_count; }; /* --- variables --- */ G_LOCK_DEFINE_STATIC (closure_array_mutex); G_LOCK_DEFINE_STATIC (weak_refs_mutex); G_LOCK_DEFINE_STATIC (toggle_refs_mutex); static GQuark quark_closure_array = 0; static GQuark quark_weak_refs = 0; static GQuark quark_toggle_refs = 0; static GQuark quark_notify_queue; static GParamSpecPool *pspec_pool = NULL; static gulong gobject_signals[LAST_SIGNAL] = { 0, }; static guint (*floating_flag_handler) (GObject*, gint) = object_floating_flag_handler; G_LOCK_DEFINE_STATIC (construction_mutex); static GSList *construction_objects = NULL; /* qdata pointing to GSList, protected by weak_locations_lock */ static GQuark quark_weak_locations = 0; static GRWLock weak_locations_lock; G_LOCK_DEFINE_STATIC(notify_lock); /* --- functions --- */ static void g_object_notify_queue_free (gpointer data) { GObjectNotifyQueue *nqueue = data; g_slist_free (nqueue->pspecs); g_slice_free (GObjectNotifyQueue, nqueue); } static GObjectNotifyQueue* g_object_notify_queue_freeze (GObject *object, gboolean conditional) { GObjectNotifyQueue *nqueue; G_LOCK(notify_lock); nqueue = g_datalist_id_get_data (&object->qdata, quark_notify_queue); if (!nqueue) { if (conditional) { G_UNLOCK(notify_lock); return NULL; } nqueue = g_slice_new0 (GObjectNotifyQueue); g_datalist_id_set_data_full (&object->qdata, quark_notify_queue, nqueue, g_object_notify_queue_free); } if (nqueue->freeze_count >= 65535) g_critical("Free queue for %s (%p) is larger than 65535," " called g_object_freeze_notify() too often." " Forgot to call g_object_thaw_notify() or infinite loop", G_OBJECT_TYPE_NAME (object), object); else nqueue->freeze_count++; G_UNLOCK(notify_lock); return nqueue; } static void g_object_notify_queue_thaw (GObject *object, GObjectNotifyQueue *nqueue) { GParamSpec *pspecs_mem[16], **pspecs, **free_me = NULL; GSList *slist; guint n_pspecs = 0; g_return_if_fail (nqueue->freeze_count > 0); g_return_if_fail (g_atomic_int_get(&object->ref_count) > 0); G_LOCK(notify_lock); /* Just make sure we never get into some nasty race condition */ if (G_UNLIKELY(nqueue->freeze_count == 0)) { G_UNLOCK(notify_lock); g_warning ("%s: property-changed notification for %s(%p) is not frozen", G_STRFUNC, G_OBJECT_TYPE_NAME (object), object); return; } nqueue->freeze_count--; if (nqueue->freeze_count) { G_UNLOCK(notify_lock); return; } pspecs = nqueue->n_pspecs > 16 ? free_me = g_new (GParamSpec*, nqueue->n_pspecs) : pspecs_mem; for (slist = nqueue->pspecs; slist; slist = slist->next) { pspecs[n_pspecs++] = slist->data; } g_datalist_id_set_data (&object->qdata, quark_notify_queue, NULL); G_UNLOCK(notify_lock); if (n_pspecs) G_OBJECT_GET_CLASS (object)->dispatch_properties_changed (object, n_pspecs, pspecs); g_free (free_me); } static void g_object_notify_queue_add (GObject *object, GObjectNotifyQueue *nqueue, GParamSpec *pspec) { G_LOCK(notify_lock); g_return_if_fail (nqueue->n_pspecs < 65535); if (g_slist_find (nqueue->pspecs, pspec) == NULL) { nqueue->pspecs = g_slist_prepend (nqueue->pspecs, pspec); nqueue->n_pspecs++; } G_UNLOCK(notify_lock); } #ifdef G_ENABLE_DEBUG #define IF_DEBUG(debug_type) if (_g_type_debug_flags & G_TYPE_DEBUG_ ## debug_type) G_LOCK_DEFINE_STATIC (debug_objects); static volatile GObject *g_trap_object_ref = NULL; static guint debug_objects_count = 0; static GHashTable *debug_objects_ht = NULL; static void debug_objects_foreach (gpointer key, gpointer value, gpointer user_data) { GObject *object = value; g_message ("[%p] stale %s\tref_count=%u", object, G_OBJECT_TYPE_NAME (object), object->ref_count); } #ifdef G_HAS_CONSTRUCTORS #ifdef G_DEFINE_DESTRUCTOR_NEEDS_PRAGMA #pragma G_DEFINE_DESTRUCTOR_PRAGMA_ARGS(debug_objects_atexit) #endif G_DEFINE_DESTRUCTOR(debug_objects_atexit) #endif /* G_HAS_CONSTRUCTORS */ static void debug_objects_atexit (void) { IF_DEBUG (OBJECTS) { G_LOCK (debug_objects); g_message ("stale GObjects: %u", debug_objects_count); g_hash_table_foreach (debug_objects_ht, debug_objects_foreach, NULL); G_UNLOCK (debug_objects); } } #endif /* G_ENABLE_DEBUG */ void _g_object_type_init (void) { static gboolean initialized = FALSE; static const GTypeFundamentalInfo finfo = { G_TYPE_FLAG_CLASSED | G_TYPE_FLAG_INSTANTIATABLE | G_TYPE_FLAG_DERIVABLE | G_TYPE_FLAG_DEEP_DERIVABLE, }; GTypeInfo info = { sizeof (GObjectClass), (GBaseInitFunc) g_object_base_class_init, (GBaseFinalizeFunc) g_object_base_class_finalize, (GClassInitFunc) g_object_do_class_init, NULL /* class_destroy */, NULL /* class_data */, sizeof (GObject), 0 /* n_preallocs */, (GInstanceInitFunc) g_object_init, NULL, /* value_table */ }; static const GTypeValueTable value_table = { g_value_object_init, /* value_init */ g_value_object_free_value, /* value_free */ g_value_object_copy_value, /* value_copy */ g_value_object_peek_pointer, /* value_peek_pointer */ "p", /* collect_format */ g_value_object_collect_value, /* collect_value */ "p", /* lcopy_format */ g_value_object_lcopy_value, /* lcopy_value */ }; GType type; g_return_if_fail (initialized == FALSE); initialized = TRUE; /* G_TYPE_OBJECT */ info.value_table = &value_table; type = g_type_register_fundamental (G_TYPE_OBJECT, g_intern_static_string ("GObject"), &info, &finfo, 0); g_assert (type == G_TYPE_OBJECT); g_value_register_transform_func (G_TYPE_OBJECT, G_TYPE_OBJECT, g_value_object_transform_value); #ifdef G_ENABLE_DEBUG IF_DEBUG (OBJECTS) { debug_objects_ht = g_hash_table_new (g_direct_hash, NULL); #ifndef G_HAS_CONSTRUCTORS g_atexit (debug_objects_atexit); #endif /* G_HAS_CONSTRUCTORS */ } #endif /* G_ENABLE_DEBUG */ } static void g_object_base_class_init (GObjectClass *class) { GObjectClass *pclass = g_type_class_peek_parent (class); /* Don't inherit HAS_DERIVED_CLASS flag from parent class */ class->flags &= ~CLASS_HAS_DERIVED_CLASS_FLAG; if (pclass) pclass->flags |= CLASS_HAS_DERIVED_CLASS_FLAG; /* reset instance specific fields and methods that don't get inherited */ class->construct_properties = pclass ? g_slist_copy (pclass->construct_properties) : NULL; class->get_property = NULL; class->set_property = NULL; } static void g_object_base_class_finalize (GObjectClass *class) { GList *list, *node; _g_signals_destroy (G_OBJECT_CLASS_TYPE (class)); g_slist_free (class->construct_properties); class->construct_properties = NULL; list = g_param_spec_pool_list_owned (pspec_pool, G_OBJECT_CLASS_TYPE (class)); for (node = list; node; node = node->next) { GParamSpec *pspec = node->data; g_param_spec_pool_remove (pspec_pool, pspec); PARAM_SPEC_SET_PARAM_ID (pspec, 0); g_param_spec_unref (pspec); } g_list_free (list); } static void g_object_do_class_init (GObjectClass *class) { /* read the comment about typedef struct CArray; on why not to change this quark */ quark_closure_array = g_quark_from_static_string ("GObject-closure-array"); quark_weak_refs = g_quark_from_static_string ("GObject-weak-references"); quark_weak_locations = g_quark_from_static_string ("GObject-weak-locations"); quark_toggle_refs = g_quark_from_static_string ("GObject-toggle-references"); quark_notify_queue = g_quark_from_static_string ("GObject-notify-queue"); pspec_pool = g_param_spec_pool_new (TRUE); class->constructor = g_object_constructor; class->constructed = g_object_constructed; class->set_property = g_object_do_set_property; class->get_property = g_object_do_get_property; class->dispose = g_object_real_dispose; class->finalize = g_object_finalize; class->dispatch_properties_changed = g_object_dispatch_properties_changed; class->notify = NULL; /** * GObject::notify: * @gobject: the object which received the signal. * @pspec: the #GParamSpec of the property which changed. * * The notify signal is emitted on an object when one of its * properties has been changed. Note that getting this signal * doesn't guarantee that the value of the property has actually * changed, it may also be emitted when the setter for the property * is called to reinstate the previous value. * * This signal is typically used to obtain change notification for a * single property, by specifying the property name as a detail in the * g_signal_connect() call, like this: * |[ * g_signal_connect (text_view->buffer, "notify::paste-target-list", * G_CALLBACK (gtk_text_view_target_list_notify), * text_view) * ]| * It is important to note that you must use * canonical parameter names as * detail strings for the notify signal. */ gobject_signals[NOTIFY] = g_signal_new (g_intern_static_string ("notify"), G_TYPE_FROM_CLASS (class), G_SIGNAL_RUN_FIRST | G_SIGNAL_NO_RECURSE | G_SIGNAL_DETAILED | G_SIGNAL_NO_HOOKS | G_SIGNAL_ACTION, G_STRUCT_OFFSET (GObjectClass, notify), NULL, NULL, g_cclosure_marshal_VOID__PARAM, G_TYPE_NONE, 1, G_TYPE_PARAM); /* Install a check function that we'll use to verify that classes that * implement an interface implement all properties for that interface */ g_type_add_interface_check (NULL, object_interface_check_properties); } static inline void install_property_internal (GType g_type, guint property_id, GParamSpec *pspec) { if (g_param_spec_pool_lookup (pspec_pool, pspec->name, g_type, FALSE)) { g_warning ("When installing property: type `%s' already has a property named `%s'", g_type_name (g_type), pspec->name); return; } g_param_spec_ref_sink (pspec); PARAM_SPEC_SET_PARAM_ID (pspec, property_id); g_param_spec_pool_insert (pspec_pool, pspec, g_type); } /** * g_object_class_install_property: * @oclass: a #GObjectClass * @property_id: the id for the new property * @pspec: the #GParamSpec for the new property * * Installs a new property. This is usually done in the class initializer. * * Note that it is possible to redefine a property in a derived class, * by installing a property with the same name. This can be useful at times, * e.g. to change the range of allowed values or the default value. */ void g_object_class_install_property (GObjectClass *class, guint property_id, GParamSpec *pspec) { g_return_if_fail (G_IS_OBJECT_CLASS (class)); g_return_if_fail (G_IS_PARAM_SPEC (pspec)); if (CLASS_HAS_DERIVED_CLASS (class)) g_error ("Attempt to add property %s::%s to class after it was derived", G_OBJECT_CLASS_NAME (class), pspec->name); class->flags |= CLASS_HAS_PROPS_FLAG; g_return_if_fail (pspec->flags & (G_PARAM_READABLE | G_PARAM_WRITABLE)); if (pspec->flags & G_PARAM_WRITABLE) g_return_if_fail (class->set_property != NULL); if (pspec->flags & G_PARAM_READABLE) g_return_if_fail (class->get_property != NULL); g_return_if_fail (property_id > 0); g_return_if_fail (PARAM_SPEC_PARAM_ID (pspec) == 0); /* paranoid */ if (pspec->flags & G_PARAM_CONSTRUCT) g_return_if_fail ((pspec->flags & G_PARAM_CONSTRUCT_ONLY) == 0); if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY)) g_return_if_fail (pspec->flags & G_PARAM_WRITABLE); install_property_internal (G_OBJECT_CLASS_TYPE (class), property_id, pspec); if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY)) class->construct_properties = g_slist_prepend (class->construct_properties, pspec); /* for property overrides of construct properties, we have to get rid * of the overidden inherited construct property */ pspec = g_param_spec_pool_lookup (pspec_pool, pspec->name, g_type_parent (G_OBJECT_CLASS_TYPE (class)), TRUE); if (pspec && pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY)) class->construct_properties = g_slist_remove (class->construct_properties, pspec); } /** * g_object_class_install_properties: * @oclass: a #GObjectClass * @n_pspecs: the length of the #GParamSpecs array * @pspecs: (array length=n_pspecs): the #GParamSpecs array * defining the new properties * * Installs new properties from an array of #GParamSpecs. This is * usually done in the class initializer. * * The property id of each property is the index of each #GParamSpec in * the @pspecs array. * * The property id of 0 is treated specially by #GObject and it should not * be used to store a #GParamSpec. * * This function should be used if you plan to use a static array of * #GParamSpecs and g_object_notify_by_pspec(). For instance, this * class initialization: * * |[ * enum { * PROP_0, PROP_FOO, PROP_BAR, N_PROPERTIES * }; * * static GParamSpec *obj_properties[N_PROPERTIES] = { NULL, }; * * static void * my_object_class_init (MyObjectClass *klass) * { * GObjectClass *gobject_class = G_OBJECT_CLASS (klass); * * obj_properties[PROP_FOO] = * g_param_spec_int ("foo", "Foo", "Foo", * -1, G_MAXINT, * 0, * G_PARAM_READWRITE); * * obj_properties[PROP_BAR] = * g_param_spec_string ("bar", "Bar", "Bar", * NULL, * G_PARAM_READWRITE); * * gobject_class->set_property = my_object_set_property; * gobject_class->get_property = my_object_get_property; * g_object_class_install_properties (gobject_class, * N_PROPERTIES, * obj_properties); * } * ]| * * allows calling g_object_notify_by_pspec() to notify of property changes: * * |[ * void * my_object_set_foo (MyObject *self, gint foo) * { * if (self->foo != foo) * { * self->foo = foo; * g_object_notify_by_pspec (G_OBJECT (self), obj_properties[PROP_FOO]); * } * } * ]| * * Since: 2.26 */ void g_object_class_install_properties (GObjectClass *oclass, guint n_pspecs, GParamSpec **pspecs) { GType oclass_type, parent_type; gint i; g_return_if_fail (G_IS_OBJECT_CLASS (oclass)); g_return_if_fail (n_pspecs > 1); g_return_if_fail (pspecs[0] == NULL); if (CLASS_HAS_DERIVED_CLASS (oclass)) g_error ("Attempt to add properties to %s after it was derived", G_OBJECT_CLASS_NAME (oclass)); oclass_type = G_OBJECT_CLASS_TYPE (oclass); parent_type = g_type_parent (oclass_type); /* we skip the first element of the array as it would have a 0 prop_id */ for (i = 1; i < n_pspecs; i++) { GParamSpec *pspec = pspecs[i]; g_return_if_fail (pspec != NULL); if (pspec->flags & G_PARAM_WRITABLE) g_return_if_fail (oclass->set_property != NULL); if (pspec->flags & G_PARAM_READABLE) g_return_if_fail (oclass->get_property != NULL); g_return_if_fail (PARAM_SPEC_PARAM_ID (pspec) == 0); /* paranoid */ if (pspec->flags & G_PARAM_CONSTRUCT) g_return_if_fail ((pspec->flags & G_PARAM_CONSTRUCT_ONLY) == 0); if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY)) g_return_if_fail (pspec->flags & G_PARAM_WRITABLE); oclass->flags |= CLASS_HAS_PROPS_FLAG; install_property_internal (oclass_type, i, pspec); if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY)) oclass->construct_properties = g_slist_prepend (oclass->construct_properties, pspec); /* for property overrides of construct properties, we have to get rid * of the overidden inherited construct property */ pspec = g_param_spec_pool_lookup (pspec_pool, pspec->name, parent_type, TRUE); if (pspec && pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY)) oclass->construct_properties = g_slist_remove (oclass->construct_properties, pspec); } } /** * g_object_interface_install_property: * @g_iface: any interface vtable for the interface, or the default * vtable for the interface. * @pspec: the #GParamSpec for the new property * * Add a property to an interface; this is only useful for interfaces * that are added to GObject-derived types. Adding a property to an * interface forces all objects classes with that interface to have a * compatible property. The compatible property could be a newly * created #GParamSpec, but normally * g_object_class_override_property() will be used so that the object * class only needs to provide an implementation and inherits the * property description, default value, bounds, and so forth from the * interface property. * * This function is meant to be called from the interface's default * vtable initialization function (the @class_init member of * #GTypeInfo.) It must not be called after after @class_init has * been called for any object types implementing this interface. * * Since: 2.4 */ void g_object_interface_install_property (gpointer g_iface, GParamSpec *pspec) { GTypeInterface *iface_class = g_iface; g_return_if_fail (G_TYPE_IS_INTERFACE (iface_class->g_type)); g_return_if_fail (G_IS_PARAM_SPEC (pspec)); g_return_if_fail (!G_IS_PARAM_SPEC_OVERRIDE (pspec)); /* paranoid */ g_return_if_fail (PARAM_SPEC_PARAM_ID (pspec) == 0); /* paranoid */ g_return_if_fail (pspec->flags & (G_PARAM_READABLE | G_PARAM_WRITABLE)); if (pspec->flags & G_PARAM_CONSTRUCT) g_return_if_fail ((pspec->flags & G_PARAM_CONSTRUCT_ONLY) == 0); if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY)) g_return_if_fail (pspec->flags & G_PARAM_WRITABLE); install_property_internal (iface_class->g_type, 0, pspec); } /** * g_object_class_find_property: * @oclass: a #GObjectClass * @property_name: the name of the property to look up * * Looks up the #GParamSpec for a property of a class. * * Returns: (transfer none): the #GParamSpec for the property, or * %NULL if the class doesn't have a property of that name */ GParamSpec* g_object_class_find_property (GObjectClass *class, const gchar *property_name) { GParamSpec *pspec; GParamSpec *redirect; g_return_val_if_fail (G_IS_OBJECT_CLASS (class), NULL); g_return_val_if_fail (property_name != NULL, NULL); pspec = g_param_spec_pool_lookup (pspec_pool, property_name, G_OBJECT_CLASS_TYPE (class), TRUE); if (pspec) { redirect = g_param_spec_get_redirect_target (pspec); if (redirect) return redirect; else return pspec; } else return NULL; } /** * g_object_interface_find_property: * @g_iface: any interface vtable for the interface, or the default * vtable for the interface * @property_name: name of a property to lookup. * * Find the #GParamSpec with the given name for an * interface. Generally, the interface vtable passed in as @g_iface * will be the default vtable from g_type_default_interface_ref(), or, * if you know the interface has already been loaded, * g_type_default_interface_peek(). * * Since: 2.4 * * Returns: (transfer none): the #GParamSpec for the property of the * interface with the name @property_name, or %NULL if no * such property exists. */ GParamSpec* g_object_interface_find_property (gpointer g_iface, const gchar *property_name) { GTypeInterface *iface_class = g_iface; g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface_class->g_type), NULL); g_return_val_if_fail (property_name != NULL, NULL); return g_param_spec_pool_lookup (pspec_pool, property_name, iface_class->g_type, FALSE); } /** * g_object_class_override_property: * @oclass: a #GObjectClass * @property_id: the new property ID * @name: the name of a property registered in a parent class or * in an interface of this class. * * Registers @property_id as referring to a property with the * name @name in a parent class or in an interface implemented * by @oclass. This allows this class to override * a property implementation in a parent class or to provide * the implementation of a property from an interface. * * * Internally, overriding is implemented by creating a property of type * #GParamSpecOverride; generally operations that query the properties of * the object class, such as g_object_class_find_property() or * g_object_class_list_properties() will return the overridden * property. However, in one case, the @construct_properties argument of * the @constructor virtual function, the #GParamSpecOverride is passed * instead, so that the @param_id field of the #GParamSpec will be * correct. For virtually all uses, this makes no difference. If you * need to get the overridden property, you can call * g_param_spec_get_redirect_target(). * * * Since: 2.4 */ void g_object_class_override_property (GObjectClass *oclass, guint property_id, const gchar *name) { GParamSpec *overridden = NULL; GParamSpec *new; GType parent_type; g_return_if_fail (G_IS_OBJECT_CLASS (oclass)); g_return_if_fail (property_id > 0); g_return_if_fail (name != NULL); /* Find the overridden property; first check parent types */ parent_type = g_type_parent (G_OBJECT_CLASS_TYPE (oclass)); if (parent_type != G_TYPE_NONE) overridden = g_param_spec_pool_lookup (pspec_pool, name, parent_type, TRUE); if (!overridden) { GType *ifaces; guint n_ifaces; /* Now check interfaces */ ifaces = g_type_interfaces (G_OBJECT_CLASS_TYPE (oclass), &n_ifaces); while (n_ifaces-- && !overridden) { overridden = g_param_spec_pool_lookup (pspec_pool, name, ifaces[n_ifaces], FALSE); } g_free (ifaces); } if (!overridden) { g_warning ("%s: Can't find property to override for '%s::%s'", G_STRFUNC, G_OBJECT_CLASS_NAME (oclass), name); return; } new = g_param_spec_override (name, overridden); g_object_class_install_property (oclass, property_id, new); } /** * g_object_class_list_properties: * @oclass: a #GObjectClass * @n_properties: (out): return location for the length of the returned array * * Get an array of #GParamSpec* for all properties of a class. * * Returns: (array length=n_properties) (transfer container): an array of * #GParamSpec* which should be freed after use */ GParamSpec** /* free result */ g_object_class_list_properties (GObjectClass *class, guint *n_properties_p) { GParamSpec **pspecs; guint n; g_return_val_if_fail (G_IS_OBJECT_CLASS (class), NULL); pspecs = g_param_spec_pool_list (pspec_pool, G_OBJECT_CLASS_TYPE (class), &n); if (n_properties_p) *n_properties_p = n; return pspecs; } /** * g_object_interface_list_properties: * @g_iface: any interface vtable for the interface, or the default * vtable for the interface * @n_properties_p: (out): location to store number of properties returned. * * Lists the properties of an interface.Generally, the interface * vtable passed in as @g_iface will be the default vtable from * g_type_default_interface_ref(), or, if you know the interface has * already been loaded, g_type_default_interface_peek(). * * Since: 2.4 * * Returns: (array length=n_properties_p) (transfer container): a * pointer to an array of pointers to #GParamSpec * structures. The paramspecs are owned by GLib, but the * array should be freed with g_free() when you are done with * it. */ GParamSpec** g_object_interface_list_properties (gpointer g_iface, guint *n_properties_p) { GTypeInterface *iface_class = g_iface; GParamSpec **pspecs; guint n; g_return_val_if_fail (G_TYPE_IS_INTERFACE (iface_class->g_type), NULL); pspecs = g_param_spec_pool_list (pspec_pool, iface_class->g_type, &n); if (n_properties_p) *n_properties_p = n; return pspecs; } static void g_object_init (GObject *object, GObjectClass *class) { object->ref_count = 1; object->qdata = NULL; if (CLASS_HAS_PROPS (class)) { /* freeze object's notification queue, g_object_newv() preserves pairedness */ g_object_notify_queue_freeze (object, FALSE); } if (CLASS_HAS_CUSTOM_CONSTRUCTOR (class)) { /* enter construction list for notify_queue_thaw() and to allow construct-only properties */ G_LOCK (construction_mutex); construction_objects = g_slist_prepend (construction_objects, object); G_UNLOCK (construction_mutex); } #ifdef G_ENABLE_DEBUG IF_DEBUG (OBJECTS) { G_LOCK (debug_objects); debug_objects_count++; g_hash_table_insert (debug_objects_ht, object, object); G_UNLOCK (debug_objects); } #endif /* G_ENABLE_DEBUG */ } static void g_object_do_set_property (GObject *object, guint property_id, const GValue *value, GParamSpec *pspec) { switch (property_id) { default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec); break; } } static void g_object_do_get_property (GObject *object, guint property_id, GValue *value, GParamSpec *pspec) { switch (property_id) { default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec); break; } } static void g_object_real_dispose (GObject *object) { g_signal_handlers_destroy (object); g_datalist_id_set_data (&object->qdata, quark_closure_array, NULL); g_datalist_id_set_data (&object->qdata, quark_weak_refs, NULL); } static void g_object_finalize (GObject *object) { g_datalist_clear (&object->qdata); #ifdef G_ENABLE_DEBUG IF_DEBUG (OBJECTS) { G_LOCK (debug_objects); g_assert (g_hash_table_lookup (debug_objects_ht, object) == object); g_hash_table_remove (debug_objects_ht, object); debug_objects_count--; G_UNLOCK (debug_objects); } #endif /* G_ENABLE_DEBUG */ } static void g_object_dispatch_properties_changed (GObject *object, guint n_pspecs, GParamSpec **pspecs) { guint i; for (i = 0; i < n_pspecs; i++) g_signal_emit (object, gobject_signals[NOTIFY], g_quark_from_string (pspecs[i]->name), pspecs[i]); } /** * g_object_run_dispose: * @object: a #GObject * * Releases all references to other objects. This can be used to break * reference cycles. * * This functions should only be called from object system implementations. */ void g_object_run_dispose (GObject *object) { g_return_if_fail (G_IS_OBJECT (object)); g_return_if_fail (object->ref_count > 0); g_object_ref (object); TRACE (GOBJECT_OBJECT_DISPOSE(object,G_TYPE_FROM_INSTANCE(object), 0)); G_OBJECT_GET_CLASS (object)->dispose (object); TRACE (GOBJECT_OBJECT_DISPOSE_END(object,G_TYPE_FROM_INSTANCE(object), 0)); g_object_unref (object); } /** * g_object_freeze_notify: * @object: a #GObject * * Increases the freeze count on @object. If the freeze count is * non-zero, the emission of "notify" signals on @object is * stopped. The signals are queued until the freeze count is decreased * to zero. Duplicate notifications are squashed so that at most one * #GObject::notify signal is emitted for each property modified while the * object is frozen. * * This is necessary for accessors that modify multiple properties to prevent * premature notification while the object is still being modified. */ void g_object_freeze_notify (GObject *object) { g_return_if_fail (G_IS_OBJECT (object)); if (g_atomic_int_get (&object->ref_count) == 0) return; g_object_ref (object); g_object_notify_queue_freeze (object, FALSE); g_object_unref (object); } static GParamSpec * get_notify_pspec (GParamSpec *pspec) { GParamSpec *redirected; /* we don't notify on non-READABLE parameters */ if (~pspec->flags & G_PARAM_READABLE) return NULL; /* if the paramspec is redirected, notify on the target */ redirected = g_param_spec_get_redirect_target (pspec); if (redirected != NULL) return redirected; /* else, notify normally */ return pspec; } static inline void g_object_notify_by_spec_internal (GObject *object, GParamSpec *pspec) { GParamSpec *notify_pspec; notify_pspec = get_notify_pspec (pspec); if (notify_pspec != NULL) { GObjectNotifyQueue *nqueue; /* conditional freeze: only increase freeze count if already frozen */ nqueue = g_object_notify_queue_freeze (object, TRUE); if (nqueue != NULL) { /* we're frozen, so add to the queue and release our freeze */ g_object_notify_queue_add (object, nqueue, notify_pspec); g_object_notify_queue_thaw (object, nqueue); } else /* not frozen, so just dispatch the notification directly */ G_OBJECT_GET_CLASS (object) ->dispatch_properties_changed (object, 1, ¬ify_pspec); } } /** * g_object_notify: * @object: a #GObject * @property_name: the name of a property installed on the class of @object. * * Emits a "notify" signal for the property @property_name on @object. * * When possible, eg. when signaling a property change from within the class * that registered the property, you should use g_object_notify_by_pspec() * instead. */ void g_object_notify (GObject *object, const gchar *property_name) { GParamSpec *pspec; g_return_if_fail (G_IS_OBJECT (object)); g_return_if_fail (property_name != NULL); if (g_atomic_int_get (&object->ref_count) == 0) return; g_object_ref (object); /* We don't need to get the redirect target * (by, e.g. calling g_object_class_find_property()) * because g_object_notify_queue_add() does that */ pspec = g_param_spec_pool_lookup (pspec_pool, property_name, G_OBJECT_TYPE (object), TRUE); if (!pspec) g_warning ("%s: object class `%s' has no property named `%s'", G_STRFUNC, G_OBJECT_TYPE_NAME (object), property_name); else g_object_notify_by_spec_internal (object, pspec); g_object_unref (object); } /** * g_object_notify_by_pspec: * @object: a #GObject * @pspec: the #GParamSpec of a property installed on the class of @object. * * Emits a "notify" signal for the property specified by @pspec on @object. * * This function omits the property name lookup, hence it is faster than * g_object_notify(). * * One way to avoid using g_object_notify() from within the * class that registered the properties, and using g_object_notify_by_pspec() * instead, is to store the GParamSpec used with * g_object_class_install_property() inside a static array, e.g.: * *|[ * enum * { * PROP_0, * PROP_FOO, * PROP_LAST * }; * * static GParamSpec *properties[PROP_LAST]; * * static void * my_object_class_init (MyObjectClass *klass) * { * properties[PROP_FOO] = g_param_spec_int ("foo", "Foo", "The foo", * 0, 100, * 50, * G_PARAM_READWRITE); * g_object_class_install_property (gobject_class, * PROP_FOO, * properties[PROP_FOO]); * } * ]| * * and then notify a change on the "foo" property with: * * |[ * g_object_notify_by_pspec (self, properties[PROP_FOO]); * ]| * * Since: 2.26 */ void g_object_notify_by_pspec (GObject *object, GParamSpec *pspec) { g_return_if_fail (G_IS_OBJECT (object)); g_return_if_fail (G_IS_PARAM_SPEC (pspec)); g_object_ref (object); g_object_notify_by_spec_internal (object, pspec); g_object_unref (object); } /** * g_object_thaw_notify: * @object: a #GObject * * Reverts the effect of a previous call to * g_object_freeze_notify(). The freeze count is decreased on @object * and when it reaches zero, queued "notify" signals are emitted. * * Duplicate notifications for each property are squashed so that at most one * #GObject::notify signal is emitted for each property. * * It is an error to call this function when the freeze count is zero. */ void g_object_thaw_notify (GObject *object) { GObjectNotifyQueue *nqueue; g_return_if_fail (G_IS_OBJECT (object)); if (g_atomic_int_get (&object->ref_count) == 0) return; g_object_ref (object); /* FIXME: Freezing is the only way to get at the notify queue. * So we freeze once and then thaw twice. */ nqueue = g_object_notify_queue_freeze (object, FALSE); g_object_notify_queue_thaw (object, nqueue); g_object_notify_queue_thaw (object, nqueue); g_object_unref (object); } static inline void object_get_property (GObject *object, GParamSpec *pspec, GValue *value) { GObjectClass *class = g_type_class_peek (pspec->owner_type); guint param_id = PARAM_SPEC_PARAM_ID (pspec); GParamSpec *redirect; if (class == NULL) { g_warning ("'%s::%s' is not a valid property name; '%s' is not a GObject subtype", g_type_name (pspec->owner_type), pspec->name, g_type_name (pspec->owner_type)); return; } redirect = g_param_spec_get_redirect_target (pspec); if (redirect) pspec = redirect; class->get_property (object, param_id, value, pspec); } static inline void object_set_property (GObject *object, GParamSpec *pspec, const GValue *value, GObjectNotifyQueue *nqueue) { GValue tmp_value = G_VALUE_INIT; GObjectClass *class = g_type_class_peek (pspec->owner_type); guint param_id = PARAM_SPEC_PARAM_ID (pspec); GParamSpec *redirect; static const gchar * enable_diagnostic = NULL; if (class == NULL) { g_warning ("'%s::%s' is not a valid property name; '%s' is not a GObject subtype", g_type_name (pspec->owner_type), pspec->name, g_type_name (pspec->owner_type)); return; } redirect = g_param_spec_get_redirect_target (pspec); if (redirect) pspec = redirect; if (G_UNLIKELY (!enable_diagnostic)) { enable_diagnostic = g_getenv ("G_ENABLE_DIAGNOSTIC"); if (!enable_diagnostic) enable_diagnostic = "0"; } if (enable_diagnostic[0] == '1') { if (pspec->flags & G_PARAM_DEPRECATED) g_warning ("The property %s:%s is deprecated and shouldn't be used " "anymore. It will be removed in a future version.", G_OBJECT_TYPE_NAME (object), pspec->name); } /* provide a copy to work from, convert (if necessary) and validate */ g_value_init (&tmp_value, pspec->value_type); if (!g_value_transform (value, &tmp_value)) g_warning ("unable to set property `%s' of type `%s' from value of type `%s'", pspec->name, g_type_name (pspec->value_type), G_VALUE_TYPE_NAME (value)); else if (g_param_value_validate (pspec, &tmp_value) && !(pspec->flags & G_PARAM_LAX_VALIDATION)) { gchar *contents = g_strdup_value_contents (value); g_warning ("value \"%s\" of type `%s' is invalid or out of range for property `%s' of type `%s'", contents, G_VALUE_TYPE_NAME (value), pspec->name, g_type_name (pspec->value_type)); g_free (contents); } else { GParamSpec *notify_pspec; class->set_property (object, param_id, &tmp_value, pspec); notify_pspec = get_notify_pspec (pspec); if (notify_pspec != NULL) g_object_notify_queue_add (object, nqueue, notify_pspec); } g_value_unset (&tmp_value); } static void object_interface_check_properties (gpointer func_data, gpointer g_iface) { GTypeInterface *iface_class = g_iface; GObjectClass *class; GType iface_type = iface_class->g_type; GParamSpec **pspecs; guint n; class = g_type_class_ref (iface_class->g_instance_type); if (!G_IS_OBJECT_CLASS (class)) return; pspecs = g_param_spec_pool_list (pspec_pool, iface_type, &n); while (n--) { GParamSpec *class_pspec = g_param_spec_pool_lookup (pspec_pool, pspecs[n]->name, G_OBJECT_CLASS_TYPE (class), TRUE); if (!class_pspec) { g_critical ("Object class %s doesn't implement property " "'%s' from interface '%s'", g_type_name (G_OBJECT_CLASS_TYPE (class)), pspecs[n]->name, g_type_name (iface_type)); continue; } /* We do a number of checks on the properties of an interface to * make sure that all classes implementing the interface are * overriding the properties in a sane way. * * We do the checks in order of importance so that we can give * more useful error messages first. * * First, we check that the implementation doesn't remove the * basic functionality (readability, writability) advertised by * the interface. Next, we check that it doesn't introduce * additional restrictions (such as construct-only). Finally, we * make sure the types are compatible. */ #define SUBSET(a,b,mask) (((a) & ~(b) & (mask)) == 0) /* If the property on the interface is readable then the * implementation must be readable. If the interface is writable * then the implementation must be writable. */ if (!SUBSET (pspecs[n]->flags, class_pspec->flags, G_PARAM_READABLE | G_PARAM_WRITABLE)) { g_critical ("Flags for property '%s' on class '%s' remove functionality compared with the " "property on interface '%s'\n", pspecs[n]->name, g_type_name (G_OBJECT_CLASS_TYPE (class)), g_type_name (iface_type)); continue; } /* If the property on the interface is writable then we need to * make sure the implementation doesn't introduce new restrictions * on that writability (ie: construct-only). * * If the interface was not writable to begin with then we don't * really have any problems here because "writable at construct * type only" is still more permissive than "read only". */ if (pspecs[n]->flags & G_PARAM_WRITABLE) { if (!SUBSET (class_pspec->flags, pspecs[n]->flags, G_PARAM_CONSTRUCT_ONLY)) { g_critical ("Flags for property '%s' on class '%s' introduce additional restrictions on " "writability compared with the property on interface '%s'\n", pspecs[n]->name, g_type_name (G_OBJECT_CLASS_TYPE (class)), g_type_name (iface_type)); continue; } } #undef SUBSET /* If the property on the interface is readable then we are * effectively advertising that reading the property will return a * value of a specific type. All implementations of the interface * need to return items of this type -- but may be more * restrictive. For example, it is legal to have: * * GtkWidget *get_item(); * * that is implemented by a function that always returns a * GtkEntry. In short: readability implies that the * implementation value type must be equal or more restrictive. * * Similarly, if the property on the interface is writable then * must be able to accept the property being set to any value of * that type, including subclasses. In this case, we may also be * less restrictive. For example, it is legal to have: * * set_item (GtkEntry *); * * that is implemented by a function that will actually work with * any GtkWidget. In short: writability implies that the * implementation value type must be equal or less restrictive. * * In the case that the property is both readable and writable * then the only way that both of the above can be satisfied is * with a type that is exactly equal. */ switch (pspecs[n]->flags & (G_PARAM_READABLE | G_PARAM_WRITABLE)) { case G_PARAM_READABLE | G_PARAM_WRITABLE: /* class pspec value type must have exact equality with interface */ if (pspecs[n]->value_type != class_pspec->value_type) g_critical ("Read/writable property '%s' on class '%s' has type '%s' which is not exactly equal to the " "type '%s' of the property on the interface '%s'\n", pspecs[n]->name, g_type_name (G_OBJECT_CLASS_TYPE (class)), g_type_name (G_PARAM_SPEC_VALUE_TYPE (class_pspec)), g_type_name (G_PARAM_SPEC_VALUE_TYPE (pspecs[n])), g_type_name (iface_type)); break; case G_PARAM_READABLE: /* class pspec value type equal or more restrictive than interface */ if (!g_type_is_a (class_pspec->value_type, pspecs[n]->value_type)) g_critical ("Read-only property '%s' on class '%s' has type '%s' which is not equal to or more " "restrictive than the type '%s' of the property on the interface '%s'\n", pspecs[n]->name, g_type_name (G_OBJECT_CLASS_TYPE (class)), g_type_name (G_PARAM_SPEC_VALUE_TYPE (class_pspec)), g_type_name (G_PARAM_SPEC_VALUE_TYPE (pspecs[n])), g_type_name (iface_type)); break; case G_PARAM_WRITABLE: /* class pspec value type equal or less restrictive than interface */ if (!g_type_is_a (pspecs[n]->value_type, class_pspec->value_type)) g_critical ("Write-only property '%s' on class '%s' has type '%s' which is not equal to or less " "restrictive than the type '%s' of the property on the interface '%s' \n", pspecs[n]->name, g_type_name (G_OBJECT_CLASS_TYPE (class)), g_type_name (G_PARAM_SPEC_VALUE_TYPE (class_pspec)), g_type_name (G_PARAM_SPEC_VALUE_TYPE (pspecs[n])), g_type_name (iface_type)); break; default: g_assert_not_reached (); } } g_free (pspecs); g_type_class_unref (class); } GType g_object_get_type (void) { return G_TYPE_OBJECT; } /** * g_object_new: (skip) * @object_type: the type id of the #GObject subtype to instantiate * @first_property_name: the name of the first property * @...: the value of the first property, followed optionally by more * name/value pairs, followed by %NULL * * Creates a new instance of a #GObject subtype and sets its properties. * * Construction parameters (see #G_PARAM_CONSTRUCT, #G_PARAM_CONSTRUCT_ONLY) * which are not explicitly specified are set to their default values. * * Returns: (transfer full): a new instance of @object_type */ gpointer g_object_new (GType object_type, const gchar *first_property_name, ...) { GObject *object; va_list var_args; g_return_val_if_fail (G_TYPE_IS_OBJECT (object_type), NULL); /* short circuit for calls supplying no properties */ if (!first_property_name) return g_object_newv (object_type, 0, NULL); va_start (var_args, first_property_name); object = g_object_new_valist (object_type, first_property_name, var_args); va_end (var_args); return object; } static gboolean slist_maybe_remove (GSList **slist, gconstpointer data) { GSList *last = NULL, *node = *slist; while (node) { if (node->data == data) { if (last) last->next = node->next; else *slist = node->next; g_slist_free_1 (node); return TRUE; } last = node; node = last->next; } return FALSE; } static inline gboolean object_in_construction_list (GObject *object) { gboolean in_construction; G_LOCK (construction_mutex); in_construction = g_slist_find (construction_objects, object) != NULL; G_UNLOCK (construction_mutex); return in_construction; } /** * g_object_newv: * @object_type: the type id of the #GObject subtype to instantiate * @n_parameters: the length of the @parameters array * @parameters: (array length=n_parameters): an array of #GParameter * * Creates a new instance of a #GObject subtype and sets its properties. * * Construction parameters (see #G_PARAM_CONSTRUCT, #G_PARAM_CONSTRUCT_ONLY) * which are not explicitly specified are set to their default values. * * Rename to: g_object_new * Returns: (type GObject.Object) (transfer full): a new instance of * @object_type */ gpointer g_object_newv (GType object_type, guint n_parameters, GParameter *parameters) { GObjectConstructParam *cparams = NULL, *oparams; GObjectNotifyQueue *nqueue = NULL; /* shouldn't be initialized, just to silence compiler */ GObject *object; GObjectClass *class, *unref_class = NULL; GSList *slist; guint n_total_cparams = 0, n_cparams = 0, n_oparams = 0, n_cvalues; GValue *cvalues; GList *clist = NULL; gboolean newly_constructed; guint i; g_return_val_if_fail (G_TYPE_IS_OBJECT (object_type), NULL); class = g_type_class_peek_static (object_type); if (!class) class = unref_class = g_type_class_ref (object_type); for (slist = class->construct_properties; slist; slist = slist->next) { clist = g_list_prepend (clist, slist->data); n_total_cparams += 1; } if (n_parameters == 0 && n_total_cparams == 0) { /* This is a simple object with no construct properties, and * no properties are being set, so short circuit the parameter * handling. This speeds up simple object construction. */ oparams = NULL; object = class->constructor (object_type, 0, NULL); goto did_construction; } /* collect parameters, sort into construction and normal ones */ oparams = g_new (GObjectConstructParam, n_parameters); cparams = g_new (GObjectConstructParam, n_total_cparams); for (i = 0; i < n_parameters; i++) { GValue *value = ¶meters[i].value; GParamSpec *pspec = g_param_spec_pool_lookup (pspec_pool, parameters[i].name, object_type, TRUE); if (!pspec) { g_warning ("%s: object class `%s' has no property named `%s'", G_STRFUNC, g_type_name (object_type), parameters[i].name); continue; } if (!(pspec->flags & G_PARAM_WRITABLE)) { g_warning ("%s: property `%s' of object class `%s' is not writable", G_STRFUNC, pspec->name, g_type_name (object_type)); continue; } if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY)) { GList *list = g_list_find (clist, pspec); if (!list) { g_warning ("%s: construct property \"%s\" for object `%s' can't be set twice", G_STRFUNC, pspec->name, g_type_name (object_type)); continue; } cparams[n_cparams].pspec = pspec; cparams[n_cparams].value = value; n_cparams++; if (!list->prev) clist = list->next; else list->prev->next = list->next; if (list->next) list->next->prev = list->prev; g_list_free_1 (list); } else { oparams[n_oparams].pspec = pspec; oparams[n_oparams].value = value; n_oparams++; } } /* set remaining construction properties to default values */ n_cvalues = n_total_cparams - n_cparams; cvalues = g_new (GValue, n_cvalues); while (clist) { GList *tmp = clist->next; GParamSpec *pspec = clist->data; GValue *value = cvalues + n_total_cparams - n_cparams - 1; value->g_type = 0; g_value_init (value, pspec->value_type); g_param_value_set_default (pspec, value); cparams[n_cparams].pspec = pspec; cparams[n_cparams].value = value; n_cparams++; g_list_free_1 (clist); clist = tmp; } /* construct object from construction parameters */ object = class->constructor (object_type, n_total_cparams, cparams); /* free construction values */ g_free (cparams); while (n_cvalues--) g_value_unset (cvalues + n_cvalues); g_free (cvalues); did_construction: if (CLASS_HAS_CUSTOM_CONSTRUCTOR (class)) { /* adjust freeze_count according to g_object_init() and remaining properties */ G_LOCK (construction_mutex); newly_constructed = slist_maybe_remove (&construction_objects, object); G_UNLOCK (construction_mutex); } else newly_constructed = TRUE; if (CLASS_HAS_PROPS (class)) { if (newly_constructed || n_oparams) nqueue = g_object_notify_queue_freeze (object, FALSE); if (newly_constructed) g_object_notify_queue_thaw (object, nqueue); } /* set remaining properties */ for (i = 0; i < n_oparams; i++) object_set_property (object, oparams[i].pspec, oparams[i].value, nqueue); g_free (oparams); /* run 'constructed' handler if there is a custom one */ if (newly_constructed && CLASS_HAS_CUSTOM_CONSTRUCTED (class)) class->constructed (object); if (CLASS_HAS_PROPS (class)) { /* release our own freeze count and handle notifications */ if (newly_constructed || n_oparams) g_object_notify_queue_thaw (object, nqueue); } if (unref_class) g_type_class_unref (unref_class); return object; } /** * g_object_new_valist: (skip) * @object_type: the type id of the #GObject subtype to instantiate * @first_property_name: the name of the first property * @var_args: the value of the first property, followed optionally by more * name/value pairs, followed by %NULL * * Creates a new instance of a #GObject subtype and sets its properties. * * Construction parameters (see #G_PARAM_CONSTRUCT, #G_PARAM_CONSTRUCT_ONLY) * which are not explicitly specified are set to their default values. * * Returns: a new instance of @object_type */ GObject* g_object_new_valist (GType object_type, const gchar *first_property_name, va_list var_args) { GObjectClass *class; GParameter *params; const gchar *name; GObject *object; guint n_params = 0, n_alloced_params = 16; g_return_val_if_fail (G_TYPE_IS_OBJECT (object_type), NULL); if (!first_property_name) return g_object_newv (object_type, 0, NULL); class = g_type_class_ref (object_type); params = g_new0 (GParameter, n_alloced_params); name = first_property_name; while (name) { gchar *error = NULL; GParamSpec *pspec = g_param_spec_pool_lookup (pspec_pool, name, object_type, TRUE); if (!pspec) { g_warning ("%s: object class `%s' has no property named `%s'", G_STRFUNC, g_type_name (object_type), name); break; } if (n_params >= n_alloced_params) { n_alloced_params += 16; params = g_renew (GParameter, params, n_alloced_params); memset (params + n_params, 0, 16 * (sizeof *params)); } params[n_params].name = name; G_VALUE_COLLECT_INIT (¶ms[n_params].value, pspec->value_type, var_args, 0, &error); if (error) { g_warning ("%s: %s", G_STRFUNC, error); g_free (error); g_value_unset (¶ms[n_params].value); break; } n_params++; name = va_arg (var_args, gchar*); } object = g_object_newv (object_type, n_params, params); while (n_params--) g_value_unset (¶ms[n_params].value); g_free (params); g_type_class_unref (class); return object; } static GObject* g_object_constructor (GType type, guint n_construct_properties, GObjectConstructParam *construct_params) { GObject *object; /* create object */ object = (GObject*) g_type_create_instance (type); /* set construction parameters */ if (n_construct_properties) { GObjectNotifyQueue *nqueue = g_object_notify_queue_freeze (object, FALSE); /* set construct properties */ while (n_construct_properties--) { GValue *value = construct_params->value; GParamSpec *pspec = construct_params->pspec; construct_params++; object_set_property (object, pspec, value, nqueue); } g_object_notify_queue_thaw (object, nqueue); /* the notification queue is still frozen from g_object_init(), so * we don't need to handle it here, g_object_newv() takes * care of that */ } return object; } static void g_object_constructed (GObject *object) { /* empty default impl to allow unconditional upchaining */ } /** * g_object_set_valist: (skip) * @object: a #GObject * @first_property_name: name of the first property to set * @var_args: value for the first property, followed optionally by more * name/value pairs, followed by %NULL * * Sets properties on an object. */ void g_object_set_valist (GObject *object, const gchar *first_property_name, va_list var_args) { GObjectNotifyQueue *nqueue; const gchar *name; g_return_if_fail (G_IS_OBJECT (object)); g_object_ref (object); nqueue = g_object_notify_queue_freeze (object, FALSE); name = first_property_name; while (name) { GValue value = G_VALUE_INIT; GParamSpec *pspec; gchar *error = NULL; pspec = g_param_spec_pool_lookup (pspec_pool, name, G_OBJECT_TYPE (object), TRUE); if (!pspec) { g_warning ("%s: object class `%s' has no property named `%s'", G_STRFUNC, G_OBJECT_TYPE_NAME (object), name); break; } if (!(pspec->flags & G_PARAM_WRITABLE)) { g_warning ("%s: property `%s' of object class `%s' is not writable", G_STRFUNC, pspec->name, G_OBJECT_TYPE_NAME (object)); break; } if ((pspec->flags & G_PARAM_CONSTRUCT_ONLY) && !object_in_construction_list (object)) { g_warning ("%s: construct property \"%s\" for object `%s' can't be set after construction", G_STRFUNC, pspec->name, G_OBJECT_TYPE_NAME (object)); break; } G_VALUE_COLLECT_INIT (&value, pspec->value_type, var_args, 0, &error); if (error) { g_warning ("%s: %s", G_STRFUNC, error); g_free (error); g_value_unset (&value); break; } object_set_property (object, pspec, &value, nqueue); g_value_unset (&value); name = va_arg (var_args, gchar*); } g_object_notify_queue_thaw (object, nqueue); g_object_unref (object); } /** * g_object_get_valist: (skip) * @object: a #GObject * @first_property_name: name of the first property to get * @var_args: return location for the first property, followed optionally by more * name/return location pairs, followed by %NULL * * Gets properties of an object. * * In general, a copy is made of the property contents and the caller * is responsible for freeing the memory in the appropriate manner for * the type, for instance by calling g_free() or g_object_unref(). * * See g_object_get(). */ void g_object_get_valist (GObject *object, const gchar *first_property_name, va_list var_args) { const gchar *name; g_return_if_fail (G_IS_OBJECT (object)); g_object_ref (object); name = first_property_name; while (name) { GValue value = G_VALUE_INIT; GParamSpec *pspec; gchar *error; pspec = g_param_spec_pool_lookup (pspec_pool, name, G_OBJECT_TYPE (object), TRUE); if (!pspec) { g_warning ("%s: object class `%s' has no property named `%s'", G_STRFUNC, G_OBJECT_TYPE_NAME (object), name); break; } if (!(pspec->flags & G_PARAM_READABLE)) { g_warning ("%s: property `%s' of object class `%s' is not readable", G_STRFUNC, pspec->name, G_OBJECT_TYPE_NAME (object)); break; } g_value_init (&value, pspec->value_type); object_get_property (object, pspec, &value); G_VALUE_LCOPY (&value, var_args, 0, &error); if (error) { g_warning ("%s: %s", G_STRFUNC, error); g_free (error); g_value_unset (&value); break; } g_value_unset (&value); name = va_arg (var_args, gchar*); } g_object_unref (object); } /** * g_object_set: (skip) * @object: a #GObject * @first_property_name: name of the first property to set * @...: value for the first property, followed optionally by more * name/value pairs, followed by %NULL * * Sets properties on an object. */ void g_object_set (gpointer _object, const gchar *first_property_name, ...) { GObject *object = _object; va_list var_args; g_return_if_fail (G_IS_OBJECT (object)); va_start (var_args, first_property_name); g_object_set_valist (object, first_property_name, var_args); va_end (var_args); } /** * g_object_get: (skip) * @object: a #GObject * @first_property_name: name of the first property to get * @...: return location for the first property, followed optionally by more * name/return location pairs, followed by %NULL * * Gets properties of an object. * * In general, a copy is made of the property contents and the caller * is responsible for freeing the memory in the appropriate manner for * the type, for instance by calling g_free() or g_object_unref(). * * * Using g_object_get(<!-- -->) * An example of using g_object_get() to get the contents * of three properties - one of type #G_TYPE_INT, * one of type #G_TYPE_STRING, and one of type #G_TYPE_OBJECT: * * gint intval; * gchar *strval; * GObject *objval; * * g_object_get (my_object, * "int-property", &intval, * "str-property", &strval, * "obj-property", &objval, * NULL); * * // Do something with intval, strval, objval * * g_free (strval); * g_object_unref (objval); * * */ void g_object_get (gpointer _object, const gchar *first_property_name, ...) { GObject *object = _object; va_list var_args; g_return_if_fail (G_IS_OBJECT (object)); va_start (var_args, first_property_name); g_object_get_valist (object, first_property_name, var_args); va_end (var_args); } /** * g_object_set_property: * @object: a #GObject * @property_name: the name of the property to set * @value: the value * * Sets a property on an object. */ void g_object_set_property (GObject *object, const gchar *property_name, const GValue *value) { GObjectNotifyQueue *nqueue; GParamSpec *pspec; g_return_if_fail (G_IS_OBJECT (object)); g_return_if_fail (property_name != NULL); g_return_if_fail (G_IS_VALUE (value)); g_object_ref (object); nqueue = g_object_notify_queue_freeze (object, FALSE); pspec = g_param_spec_pool_lookup (pspec_pool, property_name, G_OBJECT_TYPE (object), TRUE); if (!pspec) g_warning ("%s: object class `%s' has no property named `%s'", G_STRFUNC, G_OBJECT_TYPE_NAME (object), property_name); else if (!(pspec->flags & G_PARAM_WRITABLE)) g_warning ("%s: property `%s' of object class `%s' is not writable", G_STRFUNC, pspec->name, G_OBJECT_TYPE_NAME (object)); else if ((pspec->flags & G_PARAM_CONSTRUCT_ONLY) && !object_in_construction_list (object)) g_warning ("%s: construct property \"%s\" for object `%s' can't be set after construction", G_STRFUNC, pspec->name, G_OBJECT_TYPE_NAME (object)); else object_set_property (object, pspec, value, nqueue); g_object_notify_queue_thaw (object, nqueue); g_object_unref (object); } /** * g_object_get_property: * @object: a #GObject * @property_name: the name of the property to get * @value: return location for the property value * * Gets a property of an object. @value must have been initialized to the * expected type of the property (or a type to which the expected type can be * transformed) using g_value_init(). * * In general, a copy is made of the property contents and the caller is * responsible for freeing the memory by calling g_value_unset(). * * Note that g_object_get_property() is really intended for language * bindings, g_object_get() is much more convenient for C programming. */ void g_object_get_property (GObject *object, const gchar *property_name, GValue *value) { GParamSpec *pspec; g_return_if_fail (G_IS_OBJECT (object)); g_return_if_fail (property_name != NULL); g_return_if_fail (G_IS_VALUE (value)); g_object_ref (object); pspec = g_param_spec_pool_lookup (pspec_pool, property_name, G_OBJECT_TYPE (object), TRUE); if (!pspec) g_warning ("%s: object class `%s' has no property named `%s'", G_STRFUNC, G_OBJECT_TYPE_NAME (object), property_name); else if (!(pspec->flags & G_PARAM_READABLE)) g_warning ("%s: property `%s' of object class `%s' is not readable", G_STRFUNC, pspec->name, G_OBJECT_TYPE_NAME (object)); else { GValue *prop_value, tmp_value = G_VALUE_INIT; /* auto-conversion of the callers value type */ if (G_VALUE_TYPE (value) == pspec->value_type) { g_value_reset (value); prop_value = value; } else if (!g_value_type_transformable (pspec->value_type, G_VALUE_TYPE (value))) { g_warning ("%s: can't retrieve property `%s' of type `%s' as value of type `%s'", G_STRFUNC, pspec->name, g_type_name (pspec->value_type), G_VALUE_TYPE_NAME (value)); g_object_unref (object); return; } else { g_value_init (&tmp_value, pspec->value_type); prop_value = &tmp_value; } object_get_property (object, pspec, prop_value); if (prop_value != value) { g_value_transform (prop_value, value); g_value_unset (&tmp_value); } } g_object_unref (object); } /** * g_object_connect: (skip) * @object: a #GObject * @signal_spec: the spec for the first signal * @...: #GCallback for the first signal, followed by data for the * first signal, followed optionally by more signal * spec/callback/data triples, followed by %NULL * * A convenience function to connect multiple signals at once. * * The signal specs expected by this function have the form * "modifier::signal_name", where modifier can be one of the following: * * * signal * * equivalent to g_signal_connect_data (..., NULL, 0) * * * * object_signal * object-signal * * equivalent to g_signal_connect_object (..., 0) * * * * swapped_signal * swapped-signal * * equivalent to g_signal_connect_data (..., NULL, G_CONNECT_SWAPPED) * * * * swapped_object_signal * swapped-object-signal * * equivalent to g_signal_connect_object (..., G_CONNECT_SWAPPED) * * * * signal_after * signal-after * * equivalent to g_signal_connect_data (..., NULL, G_CONNECT_AFTER) * * * * object_signal_after * object-signal-after * * equivalent to g_signal_connect_object (..., G_CONNECT_AFTER) * * * * swapped_signal_after * swapped-signal-after * * equivalent to g_signal_connect_data (..., NULL, G_CONNECT_SWAPPED | G_CONNECT_AFTER) * * * * swapped_object_signal_after * swapped-object-signal-after * * equivalent to g_signal_connect_object (..., G_CONNECT_SWAPPED | G_CONNECT_AFTER) * * * * * |[ * menu->toplevel = g_object_connect (g_object_new (GTK_TYPE_WINDOW, * "type", GTK_WINDOW_POPUP, * "child", menu, * NULL), * "signal::event", gtk_menu_window_event, menu, * "signal::size_request", gtk_menu_window_size_request, menu, * "signal::destroy", gtk_widget_destroyed, &menu->toplevel, * NULL); * ]| * * Returns: (transfer none): @object */ gpointer g_object_connect (gpointer _object, const gchar *signal_spec, ...) { GObject *object = _object; va_list var_args; g_return_val_if_fail (G_IS_OBJECT (object), NULL); g_return_val_if_fail (object->ref_count > 0, object); va_start (var_args, signal_spec); while (signal_spec) { GCallback callback = va_arg (var_args, GCallback); gpointer data = va_arg (var_args, gpointer); if (strncmp (signal_spec, "signal::", 8) == 0) g_signal_connect_data (object, signal_spec + 8, callback, data, NULL, 0); else if (strncmp (signal_spec, "object_signal::", 15) == 0 || strncmp (signal_spec, "object-signal::", 15) == 0) g_signal_connect_object (object, signal_spec + 15, callback, data, 0); else if (strncmp (signal_spec, "swapped_signal::", 16) == 0 || strncmp (signal_spec, "swapped-signal::", 16) == 0) g_signal_connect_data (object, signal_spec + 16, callback, data, NULL, G_CONNECT_SWAPPED); else if (strncmp (signal_spec, "swapped_object_signal::", 23) == 0 || strncmp (signal_spec, "swapped-object-signal::", 23) == 0) g_signal_connect_object (object, signal_spec + 23, callback, data, G_CONNECT_SWAPPED); else if (strncmp (signal_spec, "signal_after::", 14) == 0 || strncmp (signal_spec, "signal-after::", 14) == 0) g_signal_connect_data (object, signal_spec + 14, callback, data, NULL, G_CONNECT_AFTER); else if (strncmp (signal_spec, "object_signal_after::", 21) == 0 || strncmp (signal_spec, "object-signal-after::", 21) == 0) g_signal_connect_object (object, signal_spec + 21, callback, data, G_CONNECT_AFTER); else if (strncmp (signal_spec, "swapped_signal_after::", 22) == 0 || strncmp (signal_spec, "swapped-signal-after::", 22) == 0) g_signal_connect_data (object, signal_spec + 22, callback, data, NULL, G_CONNECT_SWAPPED | G_CONNECT_AFTER); else if (strncmp (signal_spec, "swapped_object_signal_after::", 29) == 0 || strncmp (signal_spec, "swapped-object-signal-after::", 29) == 0) g_signal_connect_object (object, signal_spec + 29, callback, data, G_CONNECT_SWAPPED | G_CONNECT_AFTER); else { g_warning ("%s: invalid signal spec \"%s\"", G_STRFUNC, signal_spec); break; } signal_spec = va_arg (var_args, gchar*); } va_end (var_args); return object; } /** * g_object_disconnect: (skip) * @object: a #GObject * @signal_spec: the spec for the first signal * @...: #GCallback for the first signal, followed by data for the first signal, * followed optionally by more signal spec/callback/data triples, * followed by %NULL * * A convenience function to disconnect multiple signals at once. * * The signal specs expected by this function have the form * "any_signal", which means to disconnect any signal with matching * callback and data, or "any_signal::signal_name", which only * disconnects the signal named "signal_name". */ void g_object_disconnect (gpointer _object, const gchar *signal_spec, ...) { GObject *object = _object; va_list var_args; g_return_if_fail (G_IS_OBJECT (object)); g_return_if_fail (object->ref_count > 0); va_start (var_args, signal_spec); while (signal_spec) { GCallback callback = va_arg (var_args, GCallback); gpointer data = va_arg (var_args, gpointer); guint sid = 0, detail = 0, mask = 0; if (strncmp (signal_spec, "any_signal::", 12) == 0 || strncmp (signal_spec, "any-signal::", 12) == 0) { signal_spec += 12; mask = G_SIGNAL_MATCH_ID | G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA; } else if (strcmp (signal_spec, "any_signal") == 0 || strcmp (signal_spec, "any-signal") == 0) { signal_spec += 10; mask = G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA; } else { g_warning ("%s: invalid signal spec \"%s\"", G_STRFUNC, signal_spec); break; } if ((mask & G_SIGNAL_MATCH_ID) && !g_signal_parse_name (signal_spec, G_OBJECT_TYPE (object), &sid, &detail, FALSE)) g_warning ("%s: invalid signal name \"%s\"", G_STRFUNC, signal_spec); else if (!g_signal_handlers_disconnect_matched (object, mask | (detail ? G_SIGNAL_MATCH_DETAIL : 0), sid, detail, NULL, (gpointer)callback, data)) g_warning ("%s: signal handler %p(%p) is not connected", G_STRFUNC, callback, data); signal_spec = va_arg (var_args, gchar*); } va_end (var_args); } typedef struct { GObject *object; guint n_weak_refs; struct { GWeakNotify notify; gpointer data; } weak_refs[1]; /* flexible array */ } WeakRefStack; static void weak_refs_notify (gpointer data) { WeakRefStack *wstack = data; guint i; for (i = 0; i < wstack->n_weak_refs; i++) wstack->weak_refs[i].notify (wstack->weak_refs[i].data, wstack->object); g_free (wstack); } /** * g_object_weak_ref: (skip) * @object: #GObject to reference weakly * @notify: callback to invoke before the object is freed * @data: extra data to pass to notify * * Adds a weak reference callback to an object. Weak references are * used for notification when an object is finalized. They are called * "weak references" because they allow you to safely hold a pointer * to an object without calling g_object_ref() (g_object_ref() adds a * strong reference, that is, forces the object to stay alive). * * Note that the weak references created by this method are not * thread-safe: they cannot safely be used in one thread if the * object's last g_object_unref() might happen in another thread. * Use #GWeakRef if thread-safety is required. */ void g_object_weak_ref (GObject *object, GWeakNotify notify, gpointer data) { WeakRefStack *wstack; guint i; g_return_if_fail (G_IS_OBJECT (object)); g_return_if_fail (notify != NULL); g_return_if_fail (object->ref_count >= 1); G_LOCK (weak_refs_mutex); wstack = g_datalist_id_remove_no_notify (&object->qdata, quark_weak_refs); if (wstack) { i = wstack->n_weak_refs++; wstack = g_realloc (wstack, sizeof (*wstack) + sizeof (wstack->weak_refs[0]) * i); } else { wstack = g_renew (WeakRefStack, NULL, 1); wstack->object = object; wstack->n_weak_refs = 1; i = 0; } wstack->weak_refs[i].notify = notify; wstack->weak_refs[i].data = data; g_datalist_id_set_data_full (&object->qdata, quark_weak_refs, wstack, weak_refs_notify); G_UNLOCK (weak_refs_mutex); } /** * g_object_weak_unref: (skip) * @object: #GObject to remove a weak reference from * @notify: callback to search for * @data: data to search for * * Removes a weak reference callback to an object. */ void g_object_weak_unref (GObject *object, GWeakNotify notify, gpointer data) { WeakRefStack *wstack; gboolean found_one = FALSE; g_return_if_fail (G_IS_OBJECT (object)); g_return_if_fail (notify != NULL); G_LOCK (weak_refs_mutex); wstack = g_datalist_id_get_data (&object->qdata, quark_weak_refs); if (wstack) { guint i; for (i = 0; i < wstack->n_weak_refs; i++) if (wstack->weak_refs[i].notify == notify && wstack->weak_refs[i].data == data) { found_one = TRUE; wstack->n_weak_refs -= 1; if (i != wstack->n_weak_refs) wstack->weak_refs[i] = wstack->weak_refs[wstack->n_weak_refs]; break; } } G_UNLOCK (weak_refs_mutex); if (!found_one) g_warning ("%s: couldn't find weak ref %p(%p)", G_STRFUNC, notify, data); } /** * g_object_add_weak_pointer: (skip) * @object: The object that should be weak referenced. * @weak_pointer_location: (inout): The memory address of a pointer. * * Adds a weak reference from weak_pointer to @object to indicate that * the pointer located at @weak_pointer_location is only valid during * the lifetime of @object. When the @object is finalized, * @weak_pointer will be set to %NULL. * * Note that as with g_object_weak_ref(), the weak references created by * this method are not thread-safe: they cannot safely be used in one * thread if the object's last g_object_unref() might happen in another * thread. Use #GWeakRef if thread-safety is required. */ void g_object_add_weak_pointer (GObject *object, gpointer *weak_pointer_location) { g_return_if_fail (G_IS_OBJECT (object)); g_return_if_fail (weak_pointer_location != NULL); g_object_weak_ref (object, (GWeakNotify) g_nullify_pointer, weak_pointer_location); } /** * g_object_remove_weak_pointer: (skip) * @object: The object that is weak referenced. * @weak_pointer_location: (inout): The memory address of a pointer. * * Removes a weak reference from @object that was previously added * using g_object_add_weak_pointer(). The @weak_pointer_location has * to match the one used with g_object_add_weak_pointer(). */ void g_object_remove_weak_pointer (GObject *object, gpointer *weak_pointer_location) { g_return_if_fail (G_IS_OBJECT (object)); g_return_if_fail (weak_pointer_location != NULL); g_object_weak_unref (object, (GWeakNotify) g_nullify_pointer, weak_pointer_location); } static guint object_floating_flag_handler (GObject *object, gint job) { switch (job) { gpointer oldvalue; case +1: /* force floating if possible */ do oldvalue = g_atomic_pointer_get (&object->qdata); while (!g_atomic_pointer_compare_and_exchange ((void**) &object->qdata, oldvalue, (gpointer) ((gsize) oldvalue | OBJECT_FLOATING_FLAG))); return (gsize) oldvalue & OBJECT_FLOATING_FLAG; case -1: /* sink if possible */ do oldvalue = g_atomic_pointer_get (&object->qdata); while (!g_atomic_pointer_compare_and_exchange ((void**) &object->qdata, oldvalue, (gpointer) ((gsize) oldvalue & ~(gsize) OBJECT_FLOATING_FLAG))); return (gsize) oldvalue & OBJECT_FLOATING_FLAG; default: /* check floating */ return 0 != ((gsize) g_atomic_pointer_get (&object->qdata) & OBJECT_FLOATING_FLAG); } } /** * g_object_is_floating: * @object: (type GObject.Object): a #GObject * * Checks whether @object has a floating * reference. * * Since: 2.10 * * Returns: %TRUE if @object has a floating reference */ gboolean g_object_is_floating (gpointer _object) { GObject *object = _object; g_return_val_if_fail (G_IS_OBJECT (object), FALSE); return floating_flag_handler (object, 0); } /** * g_object_ref_sink: * @object: (type GObject.Object): a #GObject * * Increase the reference count of @object, and possibly remove the * floating reference, if @object * has a floating reference. * * In other words, if the object is floating, then this call "assumes * ownership" of the floating reference, converting it to a normal * reference by clearing the floating flag while leaving the reference * count unchanged. If the object is not floating, then this call * adds a new normal reference increasing the reference count by one. * * Since: 2.10 * * Returns: (type GObject.Object) (transfer none): @object */ gpointer g_object_ref_sink (gpointer _object) { GObject *object = _object; gboolean was_floating; g_return_val_if_fail (G_IS_OBJECT (object), object); g_return_val_if_fail (object->ref_count >= 1, object); g_object_ref (object); was_floating = floating_flag_handler (object, -1); if (was_floating) g_object_unref (object); return object; } /** * g_object_force_floating: * @object: a #GObject * * This function is intended for #GObject implementations to re-enforce a * floating object reference. * Doing this is seldom required: all * #GInitiallyUnowneds are created with a floating reference which * usually just needs to be sunken by calling g_object_ref_sink(). * * Since: 2.10 */ void g_object_force_floating (GObject *object) { g_return_if_fail (G_IS_OBJECT (object)); g_return_if_fail (object->ref_count >= 1); floating_flag_handler (object, +1); } typedef struct { GObject *object; guint n_toggle_refs; struct { GToggleNotify notify; gpointer data; } toggle_refs[1]; /* flexible array */ } ToggleRefStack; static void toggle_refs_notify (GObject *object, gboolean is_last_ref) { ToggleRefStack tstack, *tstackptr; G_LOCK (toggle_refs_mutex); tstackptr = g_datalist_id_get_data (&object->qdata, quark_toggle_refs); tstack = *tstackptr; G_UNLOCK (toggle_refs_mutex); /* Reentrancy here is not as tricky as it seems, because a toggle reference * will only be notified when there is exactly one of them. */ g_assert (tstack.n_toggle_refs == 1); tstack.toggle_refs[0].notify (tstack.toggle_refs[0].data, tstack.object, is_last_ref); } /** * g_object_add_toggle_ref: (skip) * @object: a #GObject * @notify: a function to call when this reference is the * last reference to the object, or is no longer * the last reference. * @data: data to pass to @notify * * Increases the reference count of the object by one and sets a * callback to be called when all other references to the object are * dropped, or when this is already the last reference to the object * and another reference is established. * * This functionality is intended for binding @object to a proxy * object managed by another memory manager. This is done with two * paired references: the strong reference added by * g_object_add_toggle_ref() and a reverse reference to the proxy * object which is either a strong reference or weak reference. * * The setup is that when there are no other references to @object, * only a weak reference is held in the reverse direction from @object * to the proxy object, but when there are other references held to * @object, a strong reference is held. The @notify callback is called * when the reference from @object to the proxy object should be * toggled from strong to weak (@is_last_ref * true) or weak to strong (@is_last_ref false). * * Since a (normal) reference must be held to the object before * calling g_object_add_toggle_ref(), the initial state of the reverse * link is always strong. * * Multiple toggle references may be added to the same gobject, * however if there are multiple toggle references to an object, none * of them will ever be notified until all but one are removed. For * this reason, you should only ever use a toggle reference if there * is important state in the proxy object. * * Since: 2.8 */ void g_object_add_toggle_ref (GObject *object, GToggleNotify notify, gpointer data) { ToggleRefStack *tstack; guint i; g_return_if_fail (G_IS_OBJECT (object)); g_return_if_fail (notify != NULL); g_return_if_fail (object->ref_count >= 1); g_object_ref (object); G_LOCK (toggle_refs_mutex); tstack = g_datalist_id_remove_no_notify (&object->qdata, quark_toggle_refs); if (tstack) { i = tstack->n_toggle_refs++; /* allocate i = tstate->n_toggle_refs - 1 positions beyond the 1 declared * in tstate->toggle_refs */ tstack = g_realloc (tstack, sizeof (*tstack) + sizeof (tstack->toggle_refs[0]) * i); } else { tstack = g_renew (ToggleRefStack, NULL, 1); tstack->object = object; tstack->n_toggle_refs = 1; i = 0; } /* Set a flag for fast lookup after adding the first toggle reference */ if (tstack->n_toggle_refs == 1) g_datalist_set_flags (&object->qdata, OBJECT_HAS_TOGGLE_REF_FLAG); tstack->toggle_refs[i].notify = notify; tstack->toggle_refs[i].data = data; g_datalist_id_set_data_full (&object->qdata, quark_toggle_refs, tstack, (GDestroyNotify)g_free); G_UNLOCK (toggle_refs_mutex); } /** * g_object_remove_toggle_ref: (skip) * @object: a #GObject * @notify: a function to call when this reference is the * last reference to the object, or is no longer * the last reference. * @data: data to pass to @notify * * Removes a reference added with g_object_add_toggle_ref(). The * reference count of the object is decreased by one. * * Since: 2.8 */ void g_object_remove_toggle_ref (GObject *object, GToggleNotify notify, gpointer data) { ToggleRefStack *tstack; gboolean found_one = FALSE; g_return_if_fail (G_IS_OBJECT (object)); g_return_if_fail (notify != NULL); G_LOCK (toggle_refs_mutex); tstack = g_datalist_id_get_data (&object->qdata, quark_toggle_refs); if (tstack) { guint i; for (i = 0; i < tstack->n_toggle_refs; i++) if (tstack->toggle_refs[i].notify == notify && tstack->toggle_refs[i].data == data) { found_one = TRUE; tstack->n_toggle_refs -= 1; if (i != tstack->n_toggle_refs) tstack->toggle_refs[i] = tstack->toggle_refs[tstack->n_toggle_refs]; if (tstack->n_toggle_refs == 0) g_datalist_unset_flags (&object->qdata, OBJECT_HAS_TOGGLE_REF_FLAG); break; } } G_UNLOCK (toggle_refs_mutex); if (found_one) g_object_unref (object); else g_warning ("%s: couldn't find toggle ref %p(%p)", G_STRFUNC, notify, data); } /** * g_object_ref: * @object: (type GObject.Object): a #GObject * * Increases the reference count of @object. * * Returns: (type GObject.Object) (transfer none): the same @object */ gpointer g_object_ref (gpointer _object) { GObject *object = _object; gint old_val; g_return_val_if_fail (G_IS_OBJECT (object), NULL); g_return_val_if_fail (object->ref_count > 0, NULL); #ifdef G_ENABLE_DEBUG if (g_trap_object_ref == object) G_BREAKPOINT (); #endif /* G_ENABLE_DEBUG */ old_val = g_atomic_int_add (&object->ref_count, 1); if (old_val == 1 && OBJECT_HAS_TOGGLE_REF (object)) toggle_refs_notify (object, FALSE); TRACE (GOBJECT_OBJECT_REF(object,G_TYPE_FROM_INSTANCE(object),old_val)); return object; } /** * g_object_unref: * @object: (type GObject.Object): a #GObject * * Decreases the reference count of @object. When its reference count * drops to 0, the object is finalized (i.e. its memory is freed). */ void g_object_unref (gpointer _object) { GObject *object = _object; gint old_ref; g_return_if_fail (G_IS_OBJECT (object)); g_return_if_fail (object->ref_count > 0); #ifdef G_ENABLE_DEBUG if (g_trap_object_ref == object) G_BREAKPOINT (); #endif /* G_ENABLE_DEBUG */ /* here we want to atomically do: if (ref_count>1) { ref_count--; return; } */ retry_atomic_decrement1: old_ref = g_atomic_int_get (&object->ref_count); if (old_ref > 1) { /* valid if last 2 refs are owned by this call to unref and the toggle_ref */ gboolean has_toggle_ref = OBJECT_HAS_TOGGLE_REF (object); if (!g_atomic_int_compare_and_exchange ((int *)&object->ref_count, old_ref, old_ref - 1)) goto retry_atomic_decrement1; TRACE (GOBJECT_OBJECT_UNREF(object,G_TYPE_FROM_INSTANCE(object),old_ref)); /* if we went from 2->1 we need to notify toggle refs if any */ if (old_ref == 2 && has_toggle_ref) /* The last ref being held in this case is owned by the toggle_ref */ toggle_refs_notify (object, TRUE); } else { GSList **weak_locations; /* The only way that this object can live at this point is if * there are outstanding weak references already established * before we got here. * * If there were not already weak references then no more can be * established at this time, because the other thread would have * to hold a strong ref in order to call * g_object_add_weak_pointer() and then we wouldn't be here. */ weak_locations = g_datalist_id_get_data (&object->qdata, quark_weak_locations); if (weak_locations != NULL) { g_rw_lock_writer_lock (&weak_locations_lock); /* It is possible that one of the weak references beat us to * the lock. Make sure the refcount is still what we expected * it to be. */ old_ref = g_atomic_int_get (&object->ref_count); if (old_ref != 1) { g_rw_lock_writer_unlock (&weak_locations_lock); goto retry_atomic_decrement1; } /* We got the lock first, so the object will definitely die * now. Clear out all the weak references. */ while (*weak_locations) { GWeakRef *weak_ref_location = (*weak_locations)->data; weak_ref_location->priv.p = NULL; *weak_locations = g_slist_delete_link (*weak_locations, *weak_locations); } g_rw_lock_writer_unlock (&weak_locations_lock); } /* we are about to remove the last reference */ TRACE (GOBJECT_OBJECT_DISPOSE(object,G_TYPE_FROM_INSTANCE(object), 1)); G_OBJECT_GET_CLASS (object)->dispose (object); TRACE (GOBJECT_OBJECT_DISPOSE_END(object,G_TYPE_FROM_INSTANCE(object), 1)); /* may have been re-referenced meanwhile */ retry_atomic_decrement2: old_ref = g_atomic_int_get ((int *)&object->ref_count); if (old_ref > 1) { /* valid if last 2 refs are owned by this call to unref and the toggle_ref */ gboolean has_toggle_ref = OBJECT_HAS_TOGGLE_REF (object); if (!g_atomic_int_compare_and_exchange ((int *)&object->ref_count, old_ref, old_ref - 1)) goto retry_atomic_decrement2; TRACE (GOBJECT_OBJECT_UNREF(object,G_TYPE_FROM_INSTANCE(object),old_ref)); /* if we went from 2->1 we need to notify toggle refs if any */ if (old_ref == 2 && has_toggle_ref) /* The last ref being held in this case is owned by the toggle_ref */ toggle_refs_notify (object, TRUE); return; } /* we are still in the process of taking away the last ref */ g_datalist_id_set_data (&object->qdata, quark_closure_array, NULL); g_signal_handlers_destroy (object); g_datalist_id_set_data (&object->qdata, quark_weak_refs, NULL); /* decrement the last reference */ old_ref = g_atomic_int_add (&object->ref_count, -1); TRACE (GOBJECT_OBJECT_UNREF(object,G_TYPE_FROM_INSTANCE(object),old_ref)); /* may have been re-referenced meanwhile */ if (G_LIKELY (old_ref == 1)) { TRACE (GOBJECT_OBJECT_FINALIZE(object,G_TYPE_FROM_INSTANCE(object))); G_OBJECT_GET_CLASS (object)->finalize (object); TRACE (GOBJECT_OBJECT_FINALIZE_END(object,G_TYPE_FROM_INSTANCE(object))); #ifdef G_ENABLE_DEBUG IF_DEBUG (OBJECTS) { /* catch objects not chaining finalize handlers */ G_LOCK (debug_objects); g_assert (g_hash_table_lookup (debug_objects_ht, object) == NULL); G_UNLOCK (debug_objects); } #endif /* G_ENABLE_DEBUG */ g_type_free_instance ((GTypeInstance*) object); } } } /** * g_clear_object: (skip) * @object_ptr: a pointer to a #GObject reference * * Clears a reference to a #GObject. * * @object_ptr must not be %NULL. * * If the reference is %NULL then this function does nothing. * Otherwise, the reference count of the object is decreased and the * pointer is set to %NULL. * * This function is threadsafe and modifies the pointer atomically, * using memory barriers where needed. * * A macro is also included that allows this function to be used without * pointer casts. * * Since: 2.28 **/ #undef g_clear_object void g_clear_object (volatile GObject **object_ptr) { g_clear_pointer (object_ptr, g_object_unref); } /** * g_object_get_qdata: * @object: The GObject to get a stored user data pointer from * @quark: A #GQuark, naming the user data pointer * * This function gets back user data pointers stored via * g_object_set_qdata(). * * Returns: (transfer none): The user data pointer set, or %NULL */ gpointer g_object_get_qdata (GObject *object, GQuark quark) { g_return_val_if_fail (G_IS_OBJECT (object), NULL); return quark ? g_datalist_id_get_data (&object->qdata, quark) : NULL; } /** * g_object_set_qdata: (skip) * @object: The GObject to set store a user data pointer * @quark: A #GQuark, naming the user data pointer * @data: An opaque user data pointer * * This sets an opaque, named pointer on an object. * The name is specified through a #GQuark (retrived e.g. via * g_quark_from_static_string()), and the pointer * can be gotten back from the @object with g_object_get_qdata() * until the @object is finalized. * Setting a previously set user data pointer, overrides (frees) * the old pointer set, using #NULL as pointer essentially * removes the data stored. */ void g_object_set_qdata (GObject *object, GQuark quark, gpointer data) { g_return_if_fail (G_IS_OBJECT (object)); g_return_if_fail (quark > 0); g_datalist_id_set_data (&object->qdata, quark, data); } /** * g_object_dup_qdata: * @object: the #GObject to store user data on * @quark: a #GQuark, naming the user data pointer * @dup_func: (allow-none): function to dup the value * @user_data: (allow-none): passed as user_data to @dup_func * * This is a variant of g_object_get_qdata() which returns * a 'duplicate' of the value. @dup_func defines the * meaning of 'duplicate' in this context, it could e.g. * take a reference on a ref-counted object. * * If the @quark is not set on the object then @dup_func * will be called with a %NULL argument. * * Note that @dup_func is called while user data of @object * is locked. * * This function can be useful to avoid races when multiple * threads are using object data on the same key on the same * object. * * Returns: the result of calling @dup_func on the value * associated with @quark on @object, or %NULL if not set. * If @dup_func is %NULL, the value is returned * unmodified. * * Since: 2.34 */ gpointer g_object_dup_qdata (GObject *object, GQuark quark, GDuplicateFunc dup_func, gpointer user_data) { g_return_val_if_fail (G_IS_OBJECT (object), NULL); g_return_val_if_fail (quark > 0, NULL); return g_datalist_id_dup_data (&object->qdata, quark, dup_func, user_data); } /** * g_object_replace_qdata: * @object: the #GObject to store user data on * @quark: a #GQuark, naming the user data pointer * @oldval: (allow-none): the old value to compare against * @newval: (allow-none): the new value * @destroy: (allow-none): a destroy notify for the new value * @old_destroy: (allow-none): destroy notify for the existing value * * Compares the user data for the key @quark on @object with * @oldval, and if they are the same, replaces @oldval with * @newval. * * This is like a typical atomic compare-and-exchange * operation, for user data on an object. * * If the previous value was replaced then ownership of the * old value (@oldval) is passed to the caller, including * the registred destroy notify for it (passed out in @old_destroy). * Its up to the caller to free this as he wishes, which may * or may not include using @old_destroy as sometimes replacement * should not destroy the object in the normal way. * * Return: %TRUE if the existing value for @quark was replaced * by @newval, %FALSE otherwise. * * Since: 2.34 */ gboolean g_object_replace_qdata (GObject *object, GQuark quark, gpointer oldval, gpointer newval, GDestroyNotify destroy, GDestroyNotify *old_destroy) { g_return_val_if_fail (G_IS_OBJECT (object), FALSE); g_return_val_if_fail (quark > 0, FALSE); return g_datalist_id_replace_data (&object->qdata, quark, oldval, newval, destroy, old_destroy); } /** * g_object_set_qdata_full: (skip) * @object: The GObject to set store a user data pointer * @quark: A #GQuark, naming the user data pointer * @data: An opaque user data pointer * @destroy: Function to invoke with @data as argument, when @data * needs to be freed * * This function works like g_object_set_qdata(), but in addition, * a void (*destroy) (gpointer) function may be specified which is * called with @data as argument when the @object is finalized, or * the data is being overwritten by a call to g_object_set_qdata() * with the same @quark. */ void g_object_set_qdata_full (GObject *object, GQuark quark, gpointer data, GDestroyNotify destroy) { g_return_if_fail (G_IS_OBJECT (object)); g_return_if_fail (quark > 0); g_datalist_id_set_data_full (&object->qdata, quark, data, data ? destroy : (GDestroyNotify) NULL); } /** * g_object_steal_qdata: * @object: The GObject to get a stored user data pointer from * @quark: A #GQuark, naming the user data pointer * * This function gets back user data pointers stored via * g_object_set_qdata() and removes the @data from object * without invoking its destroy() function (if any was * set). * Usually, calling this function is only required to update * user data pointers with a destroy notifier, for example: * |[ * void * object_add_to_user_list (GObject *object, * const gchar *new_string) * { * // the quark, naming the object data * GQuark quark_string_list = g_quark_from_static_string ("my-string-list"); * // retrive the old string list * GList *list = g_object_steal_qdata (object, quark_string_list); * * // prepend new string * list = g_list_prepend (list, g_strdup (new_string)); * // this changed 'list', so we need to set it again * g_object_set_qdata_full (object, quark_string_list, list, free_string_list); * } * static void * free_string_list (gpointer data) * { * GList *node, *list = data; * * for (node = list; node; node = node->next) * g_free (node->data); * g_list_free (list); * } * ]| * Using g_object_get_qdata() in the above example, instead of * g_object_steal_qdata() would have left the destroy function set, * and thus the partial string list would have been freed upon * g_object_set_qdata_full(). * * Returns: (transfer full): The user data pointer set, or %NULL */ gpointer g_object_steal_qdata (GObject *object, GQuark quark) { g_return_val_if_fail (G_IS_OBJECT (object), NULL); g_return_val_if_fail (quark > 0, NULL); return g_datalist_id_remove_no_notify (&object->qdata, quark); } /** * g_object_get_data: * @object: #GObject containing the associations * @key: name of the key for that association * * Gets a named field from the objects table of associations (see g_object_set_data()). * * Returns: (transfer none): the data if found, or %NULL if no such data exists. */ gpointer g_object_get_data (GObject *object, const gchar *key) { g_return_val_if_fail (G_IS_OBJECT (object), NULL); g_return_val_if_fail (key != NULL, NULL); return g_datalist_get_data (&object->qdata, key); } /** * g_object_set_data: * @object: #GObject containing the associations. * @key: name of the key * @data: data to associate with that key * * Each object carries around a table of associations from * strings to pointers. This function lets you set an association. * * If the object already had an association with that name, * the old association will be destroyed. */ void g_object_set_data (GObject *object, const gchar *key, gpointer data) { g_return_if_fail (G_IS_OBJECT (object)); g_return_if_fail (key != NULL); g_datalist_id_set_data (&object->qdata, g_quark_from_string (key), data); } /** * g_object_dup_data: * @object: the #GObject to store user data on * @key: a string, naming the user data pointer * @dup_func: (allow-none): function to dup the value * @user_data: (allow-none): passed as user_data to @dup_func * * This is a variant of g_object_get_data() which returns * a 'duplicate' of the value. @dup_func defines the * meaning of 'duplicate' in this context, it could e.g. * take a reference on a ref-counted object. * * If the @key is not set on the object then @dup_func * will be called with a %NULL argument. * * Note that @dup_func is called while user data of @object * is locked. * * This function can be useful to avoid races when multiple * threads are using object data on the same key on the same * object. * * Returns: the result of calling @dup_func on the value * associated with @key on @object, or %NULL if not set. * If @dup_func is %NULL, the value is returned * unmodified. * * Since: 2.34 */ gpointer g_object_dup_data (GObject *object, const gchar *key, GDuplicateFunc dup_func, gpointer user_data) { g_return_val_if_fail (G_IS_OBJECT (object), NULL); g_return_val_if_fail (key != NULL, NULL); return g_datalist_id_dup_data (&object->qdata, g_quark_from_string (key), dup_func, user_data); } /** * g_object_replace_data: * @object: the #GObject to store user data on * @key: a string, naming the user data pointer * @oldval: (allow-none): the old value to compare against * @newval: (allow-none): the new value * @destroy: (allow-none): a destroy notify for the new value * @old_destroy: (allow-none): destroy notify for the existing value * * Compares the user data for the key @key on @object with * @oldval, and if they are the same, replaces @oldval with * @newval. * * This is like a typical atomic compare-and-exchange * operation, for user data on an object. * * If the previous value was replaced then ownership of the * old value (@oldval) is passed to the caller, including * the registred destroy notify for it (passed out in @old_destroy). * Its up to the caller to free this as he wishes, which may * or may not include using @old_destroy as sometimes replacement * should not destroy the object in the normal way. * * Return: %TRUE if the existing value for @key was replaced * by @newval, %FALSE otherwise. * * Since: 2.34 */ gboolean g_object_replace_data (GObject *object, const gchar *key, gpointer oldval, gpointer newval, GDestroyNotify destroy, GDestroyNotify *old_destroy) { g_return_val_if_fail (G_IS_OBJECT (object), FALSE); g_return_val_if_fail (key != NULL, FALSE); return g_datalist_id_replace_data (&object->qdata, g_quark_from_string (key), oldval, newval, destroy, old_destroy); } /** * g_object_set_data_full: (skip) * @object: #GObject containing the associations * @key: name of the key * @data: data to associate with that key * @destroy: function to call when the association is destroyed * * Like g_object_set_data() except it adds notification * for when the association is destroyed, either by setting it * to a different value or when the object is destroyed. * * Note that the @destroy callback is not called if @data is %NULL. */ void g_object_set_data_full (GObject *object, const gchar *key, gpointer data, GDestroyNotify destroy) { g_return_if_fail (G_IS_OBJECT (object)); g_return_if_fail (key != NULL); g_datalist_id_set_data_full (&object->qdata, g_quark_from_string (key), data, data ? destroy : (GDestroyNotify) NULL); } /** * g_object_steal_data: * @object: #GObject containing the associations * @key: name of the key * * Remove a specified datum from the object's data associations, * without invoking the association's destroy handler. * * Returns: (transfer full): the data if found, or %NULL if no such data exists. */ gpointer g_object_steal_data (GObject *object, const gchar *key) { GQuark quark; g_return_val_if_fail (G_IS_OBJECT (object), NULL); g_return_val_if_fail (key != NULL, NULL); quark = g_quark_try_string (key); return quark ? g_datalist_id_remove_no_notify (&object->qdata, quark) : NULL; } static void g_value_object_init (GValue *value) { value->data[0].v_pointer = NULL; } static void g_value_object_free_value (GValue *value) { if (value->data[0].v_pointer) g_object_unref (value->data[0].v_pointer); } static void g_value_object_copy_value (const GValue *src_value, GValue *dest_value) { if (src_value->data[0].v_pointer) dest_value->data[0].v_pointer = g_object_ref (src_value->data[0].v_pointer); else dest_value->data[0].v_pointer = NULL; } static void g_value_object_transform_value (const GValue *src_value, GValue *dest_value) { 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))) dest_value->data[0].v_pointer = g_object_ref (src_value->data[0].v_pointer); else dest_value->data[0].v_pointer = NULL; } static gpointer g_value_object_peek_pointer (const GValue *value) { return value->data[0].v_pointer; } static gchar* g_value_object_collect_value (GValue *value, guint n_collect_values, GTypeCValue *collect_values, guint collect_flags) { if (collect_values[0].v_pointer) { GObject *object = collect_values[0].v_pointer; if (object->g_type_instance.g_class == NULL) return g_strconcat ("invalid unclassed object pointer for value type `", G_VALUE_TYPE_NAME (value), "'", NULL); else if (!g_value_type_compatible (G_OBJECT_TYPE (object), G_VALUE_TYPE (value))) return g_strconcat ("invalid object type `", G_OBJECT_TYPE_NAME (object), "' for value type `", G_VALUE_TYPE_NAME (value), "'", NULL); /* never honour G_VALUE_NOCOPY_CONTENTS for ref-counted types */ value->data[0].v_pointer = g_object_ref (object); } else value->data[0].v_pointer = NULL; return NULL; } static gchar* g_value_object_lcopy_value (const GValue *value, guint n_collect_values, GTypeCValue *collect_values, guint collect_flags) { GObject **object_p = collect_values[0].v_pointer; if (!object_p) return g_strdup_printf ("value location for `%s' passed as NULL", G_VALUE_TYPE_NAME (value)); if (!value->data[0].v_pointer) *object_p = NULL; else if (collect_flags & G_VALUE_NOCOPY_CONTENTS) *object_p = value->data[0].v_pointer; else *object_p = g_object_ref (value->data[0].v_pointer); return NULL; } /** * g_value_set_object: * @value: a valid #GValue of %G_TYPE_OBJECT derived type * @v_object: (type GObject.Object) (allow-none): object value to be set * * Set the contents of a %G_TYPE_OBJECT derived #GValue to @v_object. * * g_value_set_object() increases the reference count of @v_object * (the #GValue holds a reference to @v_object). If you do not wish * to increase the reference count of the object (i.e. you wish to * pass your current reference to the #GValue because you no longer * need it), use g_value_take_object() instead. * * It is important that your #GValue holds a reference to @v_object (either its * own, or one it has taken) to ensure that the object won't be destroyed while * the #GValue still exists). */ void g_value_set_object (GValue *value, gpointer v_object) { GObject *old; g_return_if_fail (G_VALUE_HOLDS_OBJECT (value)); old = value->data[0].v_pointer; if (v_object) { g_return_if_fail (G_IS_OBJECT (v_object)); g_return_if_fail (g_value_type_compatible (G_OBJECT_TYPE (v_object), G_VALUE_TYPE (value))); value->data[0].v_pointer = v_object; g_object_ref (value->data[0].v_pointer); } else value->data[0].v_pointer = NULL; if (old) g_object_unref (old); } /** * g_value_set_object_take_ownership: (skip) * @value: a valid #GValue of %G_TYPE_OBJECT derived type * @v_object: (allow-none): object value to be set * * This is an internal function introduced mainly for C marshallers. * * Deprecated: 2.4: Use g_value_take_object() instead. */ void g_value_set_object_take_ownership (GValue *value, gpointer v_object) { g_value_take_object (value, v_object); } /** * g_value_take_object: (skip) * @value: a valid #GValue of %G_TYPE_OBJECT derived type * @v_object: (allow-none): object value to be set * * Sets the contents of a %G_TYPE_OBJECT derived #GValue to @v_object * and takes over the ownership of the callers reference to @v_object; * the caller doesn't have to unref it any more (i.e. the reference * count of the object is not increased). * * If you want the #GValue to hold its own reference to @v_object, use * g_value_set_object() instead. * * Since: 2.4 */ void g_value_take_object (GValue *value, gpointer v_object) { g_return_if_fail (G_VALUE_HOLDS_OBJECT (value)); if (value->data[0].v_pointer) { g_object_unref (value->data[0].v_pointer); value->data[0].v_pointer = NULL; } if (v_object) { g_return_if_fail (G_IS_OBJECT (v_object)); g_return_if_fail (g_value_type_compatible (G_OBJECT_TYPE (v_object), G_VALUE_TYPE (value))); value->data[0].v_pointer = v_object; /* we take over the reference count */ } } /** * g_value_get_object: * @value: a valid #GValue of %G_TYPE_OBJECT derived type * * Get the contents of a %G_TYPE_OBJECT derived #GValue. * * Returns: (type GObject.Object) (transfer none): object contents of @value */ gpointer g_value_get_object (const GValue *value) { g_return_val_if_fail (G_VALUE_HOLDS_OBJECT (value), NULL); return value->data[0].v_pointer; } /** * g_value_dup_object: * @value: a valid #GValue whose type is derived from %G_TYPE_OBJECT * * Get the contents of a %G_TYPE_OBJECT derived #GValue, increasing * its reference count. If the contents of the #GValue are %NULL, then * %NULL will be returned. * * Returns: (type GObject.Object) (transfer full): object content of @value, * should be unreferenced when no longer needed. */ gpointer g_value_dup_object (const GValue *value) { g_return_val_if_fail (G_VALUE_HOLDS_OBJECT (value), NULL); return value->data[0].v_pointer ? g_object_ref (value->data[0].v_pointer) : NULL; } /** * g_signal_connect_object: (skip) * @instance: the instance to connect to. * @detailed_signal: a string of the form "signal-name::detail". * @c_handler: the #GCallback to connect. * @gobject: the object to pass as data to @c_handler. * @connect_flags: a combination of #GConnectFlags. * * This is similar to g_signal_connect_data(), but uses a closure which * ensures that the @gobject stays alive during the call to @c_handler * by temporarily adding a reference count to @gobject. * * When the object is destroyed the signal handler will be automatically * disconnected. Note that this is not currently threadsafe (ie: * emitting a signal while @gobject is being destroyed in another thread * is not safe). * * Returns: the handler id. */ gulong g_signal_connect_object (gpointer instance, const gchar *detailed_signal, GCallback c_handler, gpointer gobject, GConnectFlags connect_flags) { g_return_val_if_fail (G_TYPE_CHECK_INSTANCE (instance), 0); g_return_val_if_fail (detailed_signal != NULL, 0); g_return_val_if_fail (c_handler != NULL, 0); if (gobject) { GClosure *closure; g_return_val_if_fail (G_IS_OBJECT (gobject), 0); closure = ((connect_flags & G_CONNECT_SWAPPED) ? g_cclosure_new_object_swap : g_cclosure_new_object) (c_handler, gobject); return g_signal_connect_closure (instance, detailed_signal, closure, connect_flags & G_CONNECT_AFTER); } else return g_signal_connect_data (instance, detailed_signal, c_handler, NULL, NULL, connect_flags); } typedef struct { GObject *object; guint n_closures; GClosure *closures[1]; /* flexible array */ } CArray; /* don't change this structure without supplying an accessor for * watched closures, e.g.: * GSList* g_object_list_watched_closures (GObject *object) * { * CArray *carray; * g_return_val_if_fail (G_IS_OBJECT (object), NULL); * carray = g_object_get_data (object, "GObject-closure-array"); * if (carray) * { * GSList *slist = NULL; * guint i; * for (i = 0; i < carray->n_closures; i++) * slist = g_slist_prepend (slist, carray->closures[i]); * return slist; * } * return NULL; * } */ static void object_remove_closure (gpointer data, GClosure *closure) { GObject *object = data; CArray *carray; guint i; G_LOCK (closure_array_mutex); carray = g_object_get_qdata (object, quark_closure_array); for (i = 0; i < carray->n_closures; i++) if (carray->closures[i] == closure) { carray->n_closures--; if (i < carray->n_closures) carray->closures[i] = carray->closures[carray->n_closures]; G_UNLOCK (closure_array_mutex); return; } G_UNLOCK (closure_array_mutex); g_assert_not_reached (); } static void destroy_closure_array (gpointer data) { CArray *carray = data; GObject *object = carray->object; guint i, n = carray->n_closures; for (i = 0; i < n; i++) { GClosure *closure = carray->closures[i]; /* removing object_remove_closure() upfront is probably faster than * letting it fiddle with quark_closure_array which is empty anyways */ g_closure_remove_invalidate_notifier (closure, object, object_remove_closure); g_closure_invalidate (closure); } g_free (carray); } /** * g_object_watch_closure: * @object: GObject restricting lifetime of @closure * @closure: GClosure to watch * * This function essentially limits the life time of the @closure to * the life time of the object. That is, when the object is finalized, * the @closure is invalidated by calling g_closure_invalidate() on * it, in order to prevent invocations of the closure with a finalized * (nonexisting) object. Also, g_object_ref() and g_object_unref() are * added as marshal guards to the @closure, to ensure that an extra * reference count is held on @object during invocation of the * @closure. Usually, this function will be called on closures that * use this @object as closure data. */ void g_object_watch_closure (GObject *object, GClosure *closure) { CArray *carray; guint i; g_return_if_fail (G_IS_OBJECT (object)); g_return_if_fail (closure != NULL); g_return_if_fail (closure->is_invalid == FALSE); g_return_if_fail (closure->in_marshal == FALSE); g_return_if_fail (object->ref_count > 0); /* this doesn't work on finalizing objects */ g_closure_add_invalidate_notifier (closure, object, object_remove_closure); g_closure_add_marshal_guards (closure, object, (GClosureNotify) g_object_ref, object, (GClosureNotify) g_object_unref); G_LOCK (closure_array_mutex); carray = g_datalist_id_remove_no_notify (&object->qdata, quark_closure_array); if (!carray) { carray = g_renew (CArray, NULL, 1); carray->object = object; carray->n_closures = 1; i = 0; } else { i = carray->n_closures++; carray = g_realloc (carray, sizeof (*carray) + sizeof (carray->closures[0]) * i); } carray->closures[i] = closure; g_datalist_id_set_data_full (&object->qdata, quark_closure_array, carray, destroy_closure_array); G_UNLOCK (closure_array_mutex); } /** * g_closure_new_object: * @sizeof_closure: the size of the structure to allocate, must be at least * sizeof (GClosure) * @object: a #GObject pointer to store in the @data field of the newly * allocated #GClosure * * A variant of g_closure_new_simple() which stores @object in the * @data field of the closure and calls g_object_watch_closure() on * @object and the created closure. This function is mainly useful * when implementing new types of closures. * * Returns: (transfer full): a newly allocated #GClosure */ GClosure* g_closure_new_object (guint sizeof_closure, GObject *object) { GClosure *closure; g_return_val_if_fail (G_IS_OBJECT (object), NULL); g_return_val_if_fail (object->ref_count > 0, NULL); /* this doesn't work on finalizing objects */ closure = g_closure_new_simple (sizeof_closure, object); g_object_watch_closure (object, closure); return closure; } /** * g_cclosure_new_object: (skip) * @callback_func: the function to invoke * @object: a #GObject pointer to pass to @callback_func * * A variant of g_cclosure_new() which uses @object as @user_data and * calls g_object_watch_closure() on @object and the created * closure. This function is useful when you have a callback closely * associated with a #GObject, and want the callback to no longer run * after the object is is freed. * * Returns: a new #GCClosure */ GClosure* g_cclosure_new_object (GCallback callback_func, GObject *object) { GClosure *closure; g_return_val_if_fail (G_IS_OBJECT (object), NULL); g_return_val_if_fail (object->ref_count > 0, NULL); /* this doesn't work on finalizing objects */ g_return_val_if_fail (callback_func != NULL, NULL); closure = g_cclosure_new (callback_func, object, NULL); g_object_watch_closure (object, closure); return closure; } /** * g_cclosure_new_object_swap: (skip) * @callback_func: the function to invoke * @object: a #GObject pointer to pass to @callback_func * * A variant of g_cclosure_new_swap() which uses @object as @user_data * and calls g_object_watch_closure() on @object and the created * closure. This function is useful when you have a callback closely * associated with a #GObject, and want the callback to no longer run * after the object is is freed. * * Returns: a new #GCClosure */ GClosure* g_cclosure_new_object_swap (GCallback callback_func, GObject *object) { GClosure *closure; g_return_val_if_fail (G_IS_OBJECT (object), NULL); g_return_val_if_fail (object->ref_count > 0, NULL); /* this doesn't work on finalizing objects */ g_return_val_if_fail (callback_func != NULL, NULL); closure = g_cclosure_new_swap (callback_func, object, NULL); g_object_watch_closure (object, closure); return closure; } gsize g_object_compat_control (gsize what, gpointer data) { switch (what) { gpointer *pp; case 1: /* floating base type */ return G_TYPE_INITIALLY_UNOWNED; case 2: /* FIXME: remove this once GLib/Gtk+ break ABI again */ floating_flag_handler = (guint(*)(GObject*,gint)) data; return 1; case 3: /* FIXME: remove this once GLib/Gtk+ break ABI again */ pp = data; *pp = floating_flag_handler; return 1; default: return 0; } } G_DEFINE_TYPE (GInitiallyUnowned, g_initially_unowned, G_TYPE_OBJECT); static void g_initially_unowned_init (GInitiallyUnowned *object) { g_object_force_floating (object); } static void g_initially_unowned_class_init (GInitiallyUnownedClass *klass) { } /** * GWeakRef: * * A structure containing a weak reference to a #GObject. It can either * be empty (i.e. point to %NULL), or point to an object for as long as * at least one "strong" reference to that object exists. Before the * object's #GObjectClass.dispose method is called, every #GWeakRef * associated with becomes empty (i.e. points to %NULL). * * Like #GValue, #GWeakRef can be statically allocated, stack- or * heap-allocated, or embedded in larger structures. * * Unlike g_object_weak_ref() and g_object_add_weak_pointer(), this weak * reference is thread-safe: converting a weak pointer to a reference is * atomic with respect to invalidation of weak pointers to destroyed * objects. * * If the object's #GObjectClass.dispose method results in additional * references to the object being held, any #GWeakRefs taken * before it was disposed will continue to point to %NULL. If * #GWeakRefs are taken after the object is disposed and * re-referenced, they will continue to point to it until its refcount * goes back to zero, at which point they too will be invalidated. */ /** * g_weak_ref_init: (skip) * @weak_ref: (inout): uninitialized or empty location for a weak * reference * @object: (allow-none): a #GObject or %NULL * * Initialise a non-statically-allocated #GWeakRef. * * This function also calls g_weak_ref_set() with @object on the * freshly-initialised weak reference. * * This function should always be matched with a call to * g_weak_ref_clear(). It is not necessary to use this function for a * #GWeakRef in static storage because it will already be * properly initialised. Just use g_weak_ref_set() directly. * * Since: 2.32 */ void g_weak_ref_init (GWeakRef *weak_ref, gpointer object) { weak_ref->priv.p = NULL; g_weak_ref_set (weak_ref, object); } /** * g_weak_ref_clear: (skip) * @weak_ref: (inout): location of a weak reference, which * may be empty * * Frees resources associated with a non-statically-allocated #GWeakRef. * After this call, the #GWeakRef is left in an undefined state. * * You should only call this on a #GWeakRef that previously had * g_weak_ref_init() called on it. * * Since: 2.32 */ void g_weak_ref_clear (GWeakRef *weak_ref) { g_weak_ref_set (weak_ref, NULL); /* be unkind */ weak_ref->priv.p = (void *) 0xccccccccu; } /** * g_weak_ref_get: (skip) * @weak_ref: (inout): location of a weak reference to a #GObject * * If @weak_ref is not empty, atomically acquire a strong * reference to the object it points to, and return that reference. * * This function is needed because of the potential race between taking * the pointer value and g_object_ref() on it, if the object was losing * its last reference at the same time in a different thread. * * The caller should release the resulting reference in the usual way, * by using g_object_unref(). * * Returns: (transfer full) (type GObject.Object): the object pointed to * by @weak_ref, or %NULL if it was empty * * Since: 2.32 */ gpointer g_weak_ref_get (GWeakRef *weak_ref) { gpointer object_or_null; g_return_val_if_fail (weak_ref!= NULL, NULL); g_rw_lock_reader_lock (&weak_locations_lock); object_or_null = weak_ref->priv.p; if (object_or_null != NULL) g_object_ref (object_or_null); g_rw_lock_reader_unlock (&weak_locations_lock); return object_or_null; } /** * g_weak_ref_set: (skip) * @weak_ref: location for a weak reference * @object: (allow-none): a #GObject or %NULL * * Change the object to which @weak_ref points, or set it to * %NULL. * * You must own a strong reference on @object while calling this * function. * * Since: 2.32 */ void g_weak_ref_set (GWeakRef *weak_ref, gpointer object) { GSList **weak_locations; GObject *new_object; GObject *old_object; g_return_if_fail (weak_ref != NULL); g_return_if_fail (object == NULL || G_IS_OBJECT (object)); new_object = object; g_rw_lock_writer_lock (&weak_locations_lock); /* We use the extra level of indirection here so that if we have ever * had a weak pointer installed at any point in time on this object, * we can see that there is a non-NULL value associated with the * weak-pointer quark and know that this value will not change at any * point in the object's lifetime. * * Both properties are important for reducing the amount of times we * need to acquire locks and for decreasing the duration of time the * lock is held while avoiding some rather tricky races. * * Specifically: we can avoid having to do an extra unconditional lock * in g_object_unref() without worrying about some extremely tricky * races. */ old_object = weak_ref->priv.p; if (new_object != old_object) { weak_ref->priv.p = new_object; /* Remove the weak ref from the old object */ if (old_object != NULL) { weak_locations = g_datalist_id_get_data (&old_object->qdata, quark_weak_locations); /* for it to point to an object, the object must have had it added once */ g_assert (weak_locations != NULL); *weak_locations = g_slist_remove (*weak_locations, weak_ref); } /* Add the weak ref to the new object */ if (new_object != NULL) { weak_locations = g_datalist_id_get_data (&new_object->qdata, quark_weak_locations); if (weak_locations == NULL) { weak_locations = g_new0 (GSList *, 1); g_datalist_id_set_data_full (&new_object->qdata, quark_weak_locations, weak_locations, g_free); } *weak_locations = g_slist_prepend (*weak_locations, weak_ref); } } g_rw_lock_writer_unlock (&weak_locations_lock); }