/* GObject - GLib Type, Object, Parameter and Signal Library * Copyright (C) 1998-1999, 2000-2001 Tim Janik and Red Hat, Inc. * * SPDX-License-Identifier: LGPL-2.1-or-later * * 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 2.1 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, see . */ /* * MT safe with regards to reference counting. */ #include "config.h" #include #include #include "../glib/glib-private.h" #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 [here][gobject-Signals]. * * For a tutorial on implementing a new GObject class, see [How to define and * implement a new GObject][howto-gobject]. For a list of naming conventions for * GObjects and their methods, see the [GType conventions][gtype-conventions]. * For the high-level concepts behind GObject, read [Instantiatable classed types: * Objects][gtype-instantiatable-classed]. * * ## Floating references # {#floating-ref} * * **Note**: Floating references are a C convenience API and should not be * used in modern GObject code. Language bindings in particular find the * concept highly problematic, as floating references are not identifiable * through annotations, and neither are deviations from the floating reference * behavior, like types that inherit from #GInitiallyUnowned and still return * a full reference from g_object_new(). * * 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() calls g_object_ref_sink() on 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. The best practice for handling * types that have initially floating references is to immediately sink those * references after g_object_new() returns, by checking if the #GType * inherits from #GInitiallyUnowned. For instance: * * |[ * GObject *res = g_object_new_with_properties (gtype, * n_props, * prop_names, * prop_values); * * // or: if (g_type_is_a (gtype, G_TYPE_INITIALLY_UNOWNED)) * if (G_IS_INITIALLY_UNOWNED (res)) * g_object_ref_sink (res); * * return res; * ]| * * 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); * else * 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_NOTIFY(class) ((class)->notify != NULL) #define CLASS_HAS_CUSTOM_DISPATCH(class) \ ((class)->dispatch_properties_changed != g_object_dispatch_properties_changed) #define CLASS_NEEDS_NOTIFY(class) \ (CLASS_HAS_NOTIFY(class) || CLASS_HAS_CUSTOM_DISPATCH(class)) #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 }; #define OPTIONAL_FLAG_IN_CONSTRUCTION (1 << 0) #define OPTIONAL_FLAG_HAS_SIGNAL_HANDLER (1 << 1) /* Set if object ever had a signal handler */ #define OPTIONAL_FLAG_HAS_NOTIFY_HANDLER (1 << 2) /* Same, specifically for "notify" */ #if SIZEOF_INT == 4 && GLIB_SIZEOF_VOID_P == 8 #define HAVE_OPTIONAL_FLAGS #endif typedef struct { GTypeInstance g_type_instance; /*< private >*/ guint ref_count; /* (atomic) */ #ifdef HAVE_OPTIONAL_FLAGS guint optional_flags; /* (atomic) */ #endif GData *qdata; } GObjectReal; G_STATIC_ASSERT(sizeof(GObject) == sizeof(GObjectReal)); G_STATIC_ASSERT(G_STRUCT_OFFSET(GObject, ref_count) == G_STRUCT_OFFSET(GObjectReal, ref_count)); G_STATIC_ASSERT(G_STRUCT_OFFSET(GObject, qdata) == G_STRUCT_OFFSET(GObjectReal, qdata)); /* --- 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 check_data, gpointer g_iface); static void weak_locations_free_unlocked (GSList **weak_locations); /* --- 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; #ifndef HAVE_OPTIONAL_FLAGS static GQuark quark_in_construction; #endif static GParamSpecPool *pspec_pool = NULL; static gulong gobject_signals[LAST_SIGNAL] = { 0, }; static guint (*floating_flag_handler) (GObject*, gint) = object_floating_flag_handler; /* 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_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_critical ("%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_assert (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 G_LOCK_DEFINE_STATIC (debug_objects); 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) { GOBJECT_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_GNUC_UNUSED /* when compiling with G_DISABLE_ASSERT */; 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); #if G_ENABLE_DEBUG /* We cannot use GOBJECT_IF_DEBUG here because of the G_HAS_CONSTRUCTORS * conditional in between, as the C spec leaves conditionals inside macro * expansions as undefined behavior. Only GCC and Clang are known to work * but compilation breaks on MSVC. * * See: https://bugzilla.gnome.org/show_bug.cgi?id=769504 */ if (_g_type_debug_flags & G_TYPE_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->n_construct_properties = g_slist_length (class->construct_properties); class->get_property = NULL; class->set_property = NULL; class->pspecs = NULL; class->n_pspecs = 0; } 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; class->n_construct_properties = 0; 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"); #ifndef HAVE_OPTIONAL_FLAGS quark_in_construction = g_quark_from_static_string ("GObject-in-construction"); #endif 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 * its value set through g_object_set_property(), g_object_set(), et al. * * Note that getting this signal doesn’t itself guarantee that the value of * the property has actually changed. When it is emitted is determined by the * derived GObject class. If the implementor did not create the property with * %G_PARAM_EXPLICIT_NOTIFY, then any call to g_object_set_property() results * in ::notify being emitted, even if the new value is the same as the old. * If they did pass %G_PARAM_EXPLICIT_NOTIFY, then this signal is emitted only * when they explicitly call g_object_notify() or g_object_notify_by_pspec(), * and common practice is to do that only when the value has actually changed. * * 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][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, NULL, 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); } /* Sinks @pspec if it’s a floating ref. */ static inline gboolean install_property_internal (GType g_type, guint property_id, GParamSpec *pspec) { g_param_spec_ref_sink (pspec); if (g_param_spec_pool_lookup (pspec_pool, pspec->name, g_type, FALSE)) { g_critical ("When installing property: type '%s' already has a property named '%s'", g_type_name (g_type), pspec->name); g_param_spec_unref (pspec); return FALSE; } PARAM_SPEC_SET_PARAM_ID (pspec, property_id); g_param_spec_pool_insert (pspec_pool, g_steal_pointer (&pspec), g_type); return TRUE; } static gboolean validate_pspec_to_install (GParamSpec *pspec) { g_return_val_if_fail (G_IS_PARAM_SPEC (pspec), FALSE); g_return_val_if_fail (PARAM_SPEC_PARAM_ID (pspec) == 0, FALSE); /* paranoid */ g_return_val_if_fail (pspec->flags & (G_PARAM_READABLE | G_PARAM_WRITABLE), FALSE); if (pspec->flags & G_PARAM_CONSTRUCT) g_return_val_if_fail ((pspec->flags & G_PARAM_CONSTRUCT_ONLY) == 0, FALSE); if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY)) g_return_val_if_fail (pspec->flags & G_PARAM_WRITABLE, FALSE); return TRUE; } /* Sinks @pspec if it’s a floating ref. */ static gboolean validate_and_install_class_property (GObjectClass *class, GType oclass_type, GType parent_type, guint property_id, GParamSpec *pspec) { if (!validate_pspec_to_install (pspec)) { g_param_spec_ref_sink (pspec); g_param_spec_unref (pspec); return FALSE; } if (pspec->flags & G_PARAM_WRITABLE) g_return_val_if_fail (class->set_property != NULL, FALSE); if (pspec->flags & G_PARAM_READABLE) g_return_val_if_fail (class->get_property != NULL, FALSE); class->flags |= CLASS_HAS_PROPS_FLAG; if (install_property_internal (oclass_type, property_id, pspec)) { if (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY)) { class->construct_properties = g_slist_append (class->construct_properties, pspec); class->n_construct_properties += 1; } /* for property overrides of construct properties, we have to get rid * of the overridden 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)) { class->construct_properties = g_slist_remove (class->construct_properties, pspec); class->n_construct_properties -= 1; } return TRUE; } else return FALSE; } /** * 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. * * All properties should be installed during the class initializer. It * is possible to install properties after that, but doing so is not * recommend, and specifically, is not guaranteed to be thread-safe vs. * use of properties on the same type on other threads. * * 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) { GType oclass_type, parent_type; g_return_if_fail (G_IS_OBJECT_CLASS (class)); g_return_if_fail (property_id > 0); oclass_type = G_OBJECT_CLASS_TYPE (class); parent_type = g_type_parent (oclass_type); 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); (void) validate_and_install_class_property (class, oclass_type, parent_type, property_id, pspec); } typedef struct { const char *name; GParamSpec *pspec; } PspecEntry; static int compare_pspec_entry (const void *a, const void *b) { const PspecEntry *ae = a; const PspecEntry *be = b; return ae->name < be->name ? -1 : (ae->name > be->name ? 1 : 0); } /* This uses pointer comparisons with @property_name, so * will only work with string literals. */ static inline GParamSpec * find_pspec (GObjectClass *class, const char *property_name) { const PspecEntry *pspecs = (const PspecEntry *)class->pspecs; gsize n_pspecs = class->n_pspecs; g_assert (n_pspecs <= G_MAXSSIZE); /* The limit for choosing between linear and binary search is * fairly arbitrary. * * Both searches use pointer comparisons against @property_name. * If this function is called with a non-static @property_name, * it will fall through to the g_param_spec_pool_lookup() case. * That’s OK; this is an opportunistic optimisation which relies * on the fact that *most* (but not all) property lookups use * static property names. */ if (n_pspecs < 10) { for (gsize i = 0; i < n_pspecs; i++) { if (pspecs[i].name == property_name) return pspecs[i].pspec; } } else { gssize lower = 0; gssize upper = (int)class->n_pspecs - 1; gssize mid; while (lower <= upper) { mid = (lower + upper) / 2; if (property_name < pspecs[mid].name) upper = mid - 1; else if (property_name > pspecs[mid].name) lower = mid + 1; else return pspecs[mid].pspec; } } return g_param_spec_pool_lookup (pspec_pool, property_name, ((GTypeClass *)class)->g_type, TRUE); } /** * 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. * * All properties should be installed during the class initializer. It * is possible to install properties after that, but doing so is not * recommend, and specifically, is not guaranteed to be thread-safe vs. * use of properties on the same type on other threads. * * 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: * * |[ * typedef enum { * PROP_FOO = 1, * PROP_BAR, * N_PROPERTIES * } MyObjectProperty; * * 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 | G_PARAM_STATIC_STRINGS); * * obj_properties[PROP_BAR] = * g_param_spec_string ("bar", "Bar", "Bar", * NULL, * G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS); * * gobject_class->set_property = my_object_set_property; * gobject_class->get_property = my_object_get_property; * g_object_class_install_properties (gobject_class, * G_N_ELEMENTS (obj_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; guint 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]; if (!validate_and_install_class_property (oclass, oclass_type, parent_type, i, pspec)) { break; } } /* Save a copy of the pspec array inside the class struct. This * makes it faster to look up pspecs for the class in future when * acting on those properties. * * If a pspec is not in this cache array, calling code will fall * back to using g_param_spec_pool_lookup(), so a pspec not being * in this array is a (potential) performance problem but not a * correctness problem. */ if (oclass->pspecs == NULL) { PspecEntry *entries; entries = g_new (PspecEntry, n_pspecs - 1); for (i = 1; i < n_pspecs; i++) { entries[i - 1].name = pspecs[i]->name; entries[i - 1].pspec = pspecs[i]; } qsort (entries, n_pspecs - 1, sizeof (PspecEntry), compare_pspec_entry); oclass->pspecs = entries; oclass->n_pspecs = n_pspecs - 1; } } /** * g_object_interface_install_property: * @g_iface: (type GObject.TypeInterface): 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. * * If @pspec is a floating reference, it will be consumed. * * 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_OVERRIDE (pspec)); /* paranoid */ if (!validate_pspec_to_install (pspec)) { g_param_spec_ref_sink (pspec); g_param_spec_unref (pspec); return; } (void) install_property_internal (iface_class->g_type, 0, pspec); } /* Inlined version of g_param_spec_get_redirect_target(), for speed */ static inline void param_spec_follow_override (GParamSpec **pspec) { if (((GTypeInstance *) (*pspec))->g_class->g_type == G_TYPE_PARAM_OVERRIDE) *pspec = ((GParamSpecOverride *) (*pspec))->overridden; } /** * 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; g_return_val_if_fail (G_IS_OBJECT_CLASS (class), NULL); g_return_val_if_fail (property_name != NULL, NULL); pspec = find_pspec (class, property_name); if (pspec) param_spec_follow_override (&pspec); return pspec; } /** * g_object_interface_find_property: * @g_iface: (type GObject.TypeInterface): any interface vtable for the * interface, or the default vtable for the interface * @property_name: name of a property to look up. * * 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_critical ("%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: (type GObject.TypeInterface): 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 inline guint object_get_optional_flags (GObject *object) { #ifdef HAVE_OPTIONAL_FLAGS GObjectReal *real = (GObjectReal *)object; return (guint)g_atomic_int_get (&real->optional_flags); #else return 0; #endif } /* Variant of object_get_optional_flags for when * we know that we have exclusive access (during * construction) */ static inline guint object_get_optional_flags_X (GObject *object) { #ifdef HAVE_OPTIONAL_FLAGS GObjectReal *real = (GObjectReal *)object; return real->optional_flags; #else return 0; #endif } #ifdef HAVE_OPTIONAL_FLAGS static inline void object_set_optional_flags (GObject *object, guint flags) { GObjectReal *real = (GObjectReal *)object; g_atomic_int_or (&real->optional_flags, flags); } /* Variant for when we have exclusive access * (during construction) */ static inline void object_set_optional_flags_X (GObject *object, guint flags) { GObjectReal *real = (GObjectReal *)object; real->optional_flags |= flags; } /* Variant for when we have exclusive access * (during construction) */ static inline void object_unset_optional_flags_X (GObject *object, guint flags) { GObjectReal *real = (GObjectReal *)object; real->optional_flags &= ~flags; } #endif gboolean _g_object_has_signal_handler (GObject *object) { #ifdef HAVE_OPTIONAL_FLAGS return (object_get_optional_flags (object) & OPTIONAL_FLAG_HAS_SIGNAL_HANDLER) != 0; #else return TRUE; #endif } static inline gboolean _g_object_has_notify_handler (GObject *object) { #ifdef HAVE_OPTIONAL_FLAGS return CLASS_NEEDS_NOTIFY (G_OBJECT_GET_CLASS (object)) || (object_get_optional_flags (object) & OPTIONAL_FLAG_HAS_NOTIFY_HANDLER) != 0; #else return TRUE; #endif } static inline gboolean _g_object_has_notify_handler_X (GObject *object) { #ifdef HAVE_OPTIONAL_FLAGS return CLASS_NEEDS_NOTIFY (G_OBJECT_GET_CLASS (object)) || (object_get_optional_flags_X (object) & OPTIONAL_FLAG_HAS_NOTIFY_HANDLER) != 0; #else return TRUE; #endif } void _g_object_set_has_signal_handler (GObject *object, guint signal_id) { #ifdef HAVE_OPTIONAL_FLAGS guint flags = OPTIONAL_FLAG_HAS_SIGNAL_HANDLER; if (signal_id == gobject_signals[NOTIFY]) flags |= OPTIONAL_FLAG_HAS_NOTIFY_HANDLER; object_set_optional_flags (object, flags); #endif } static inline gboolean object_in_construction (GObject *object) { #ifdef HAVE_OPTIONAL_FLAGS return (object_get_optional_flags (object) & OPTIONAL_FLAG_IN_CONSTRUCTION) != 0; #else return g_datalist_id_get_data (&object->qdata, quark_in_construction) != NULL; #endif } static inline void set_object_in_construction (GObject *object) { #ifdef HAVE_OPTIONAL_FLAGS object_set_optional_flags_X (object, OPTIONAL_FLAG_IN_CONSTRUCTION); #else g_datalist_id_set_data (&object->qdata, quark_in_construction, object); #endif } static inline void unset_object_in_construction (GObject *object) { #ifdef HAVE_OPTIONAL_FLAGS object_unset_optional_flags_X (object, OPTIONAL_FLAG_IN_CONSTRUCTION); #else g_datalist_id_set_data (&object->qdata, quark_in_construction, NULL); #endif } static void g_object_init (GObject *object, GObjectClass *class) { object->ref_count = 1; object->qdata = NULL; if (CLASS_HAS_PROPS (class) && CLASS_NEEDS_NOTIFY (class)) { /* freeze object's notification queue, g_object_new_internal() preserves pairedness */ g_object_notify_queue_freeze (object, FALSE); } /* mark object in-construction for notify_queue_thaw() and to allow construct-only properties */ set_object_in_construction (object); GOBJECT_IF_DEBUG (OBJECTS, { G_LOCK (debug_objects); debug_objects_count++; g_hash_table_add (debug_objects_ht, object); G_UNLOCK (debug_objects); }); } 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); g_datalist_id_set_data (&object->qdata, quark_weak_locations, NULL); } #ifdef G_ENABLE_DEBUG static gboolean floating_check (GObject *object) { static const char *g_enable_diagnostic = NULL; if (G_UNLIKELY (g_enable_diagnostic == NULL)) { g_enable_diagnostic = g_getenv ("G_ENABLE_DIAGNOSTIC"); if (g_enable_diagnostic == NULL) g_enable_diagnostic = "0"; } if (g_enable_diagnostic[0] == '1') return g_object_is_floating (object); return FALSE; } #endif static void g_object_finalize (GObject *object) { #ifdef G_ENABLE_DEBUG if (object_in_construction (object)) { g_critical ("object %s %p finalized while still in-construction", G_OBJECT_TYPE_NAME (object), object); } if (floating_check (object)) { g_critical ("A floating object %s %p was finalized. This means that someone\n" "called g_object_unref() on an object that had only a floating\n" "reference; the initial floating reference is not owned by anyone\n" "and must be removed with g_object_ref_sink().", G_OBJECT_TYPE_NAME (object), object); } #endif g_datalist_clear (&object->qdata); GOBJECT_IF_DEBUG (OBJECTS, { G_LOCK (debug_objects); g_assert (g_hash_table_contains (debug_objects_ht, object)); g_hash_table_remove (debug_objects_ht, object); debug_objects_count--; G_UNLOCK (debug_objects); }); } 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_param_spec_get_name_quark (pspecs[i]), pspecs[i]); } /** * g_object_run_dispose: * @object: a #GObject * * Releases all references to other objects. This can be used to break * reference cycles. * * This function 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 (g_atomic_int_get (&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)); #ifndef G_DISABLE_CHECKS if (G_UNLIKELY (g_atomic_int_get (&object->ref_count) == 0)) { g_critical ("Attempting to freeze the notification queue for object %s[%p]; " "Property notification does not work during instance finalization.", G_OBJECT_TYPE_NAME (object), object); return; } #endif g_object_ref (object); g_object_notify_queue_freeze (object, FALSE); g_object_unref (object); } static inline void g_object_notify_by_spec_internal (GObject *object, GParamSpec *pspec) { #ifdef HAVE_OPTIONAL_FLAGS guint object_flags; #endif gboolean needs_notify; gboolean in_init; if (G_UNLIKELY (~pspec->flags & G_PARAM_READABLE)) return; param_spec_follow_override (&pspec); #ifdef HAVE_OPTIONAL_FLAGS /* get all flags we need with a single atomic read */ object_flags = object_get_optional_flags (object); needs_notify = ((object_flags & OPTIONAL_FLAG_HAS_NOTIFY_HANDLER) != 0) || CLASS_NEEDS_NOTIFY (G_OBJECT_GET_CLASS (object)); in_init = (object_flags & OPTIONAL_FLAG_IN_CONSTRUCTION) != 0; #else needs_notify = TRUE; in_init = object_in_construction (object); #endif if (pspec != NULL && needs_notify) { GObjectNotifyQueue *nqueue; gboolean need_thaw = TRUE; /* conditional freeze: only increase freeze count if already frozen */ nqueue = g_object_notify_queue_freeze (object, TRUE); if (in_init && !nqueue) { /* We did not freeze the queue in g_object_init, but * we gained a notify handler in instance init, so * now we need to freeze just-in-time */ nqueue = g_object_notify_queue_freeze (object, FALSE); need_thaw = FALSE; } if (nqueue != NULL) { /* we're frozen, so add to the queue and release our freeze */ g_object_notify_queue_add (object, nqueue, pspec); if (need_thaw) g_object_notify_queue_thaw (object, nqueue); } else { /* * Coverity doesn’t understand the paired ref/unref here and seems to * ignore the ref, thus reports every call to g_object_notify() as * causing a double-free. That’s incorrect, but I can’t get a model * file to work for avoiding the false positives, so instead comment * out the ref/unref when doing static analysis. */ #ifndef __COVERITY__ g_object_ref (object); #endif /* not frozen, so just dispatch the notification directly */ G_OBJECT_GET_CLASS (object) ->dispatch_properties_changed (object, 1, &pspec); #ifndef __COVERITY__ g_object_unref (object); #endif } } } /** * 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. * * Note that emission of the notify signal may be blocked with * g_object_freeze_notify(). In this case, the signal emissions are queued * and will be emitted (in reverse order) when g_object_thaw_notify() is * called. */ 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); /* 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_critical ("%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_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.: * *|[ * typedef enum * { * PROP_FOO = 1, * PROP_LAST * } MyObjectProperty; * * 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_PARAM_STATIC_STRINGS); * 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_notify_by_spec_internal (object, pspec); } /** * 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, in the reverse order * in which they have been queued. * * 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)); #ifndef G_DISABLE_CHECKS if (G_UNLIKELY (g_atomic_int_get (&object->ref_count) == 0)) { g_critical ("Attempting to thaw the notification queue for object %s[%p]; " "Property notification does not work during instance finalization.", G_OBJECT_TYPE_NAME (object), object); return; } #endif 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 void maybe_issue_property_deprecation_warning (const GParamSpec *pspec) { static GHashTable *already_warned_table; static const gchar *enable_diagnostic; static GMutex already_warned_lock; gboolean already; if (g_once_init_enter (&enable_diagnostic)) { const gchar *value = g_getenv ("G_ENABLE_DIAGNOSTIC"); if (!value) value = "0"; g_once_init_leave (&enable_diagnostic, value); } if (enable_diagnostic[0] == '0') return; /* We hash only on property names: this means that we could end up in * a situation where we fail to emit a warning about a pair of * same-named deprecated properties used on two separate types. * That's pretty unlikely to occur, and even if it does, you'll still * have seen the warning for the first one... * * Doing it this way lets us hash directly on the (interned) property * name pointers. */ g_mutex_lock (&already_warned_lock); if (already_warned_table == NULL) already_warned_table = g_hash_table_new (NULL, NULL); already = g_hash_table_contains (already_warned_table, (gpointer) pspec->name); if (!already) g_hash_table_add (already_warned_table, (gpointer) pspec->name); g_mutex_unlock (&already_warned_lock); if (!already) g_warning ("The property %s:%s is deprecated and shouldn't be used " "anymore. It will be removed in a future version.", g_type_name (pspec->owner_type), pspec->name); } static inline void consider_issuing_property_deprecation_warning (const GParamSpec *pspec) { if (G_UNLIKELY (pspec->flags & G_PARAM_DEPRECATED)) maybe_issue_property_deprecation_warning (pspec); } static inline void object_get_property (GObject *object, GParamSpec *pspec, GValue *value) { GTypeInstance *inst = (GTypeInstance *) object; GObjectClass *class; guint param_id = PARAM_SPEC_PARAM_ID (pspec); if (G_LIKELY (inst->g_class->g_type == pspec->owner_type)) class = (GObjectClass *) inst->g_class; else class = g_type_class_peek (pspec->owner_type); g_assert (class != NULL); param_spec_follow_override (&pspec); consider_issuing_property_deprecation_warning (pspec); class->get_property (object, param_id, value, pspec); } static inline void object_set_property (GObject *object, GParamSpec *pspec, const GValue *value, GObjectNotifyQueue *nqueue, gboolean user_specified) { GTypeInstance *inst = (GTypeInstance *) object; GObjectClass *class; GParamSpecClass *pclass; guint param_id = PARAM_SPEC_PARAM_ID (pspec); if (G_LIKELY (inst->g_class->g_type == pspec->owner_type)) class = (GObjectClass *) inst->g_class; else class = g_type_class_peek (pspec->owner_type); g_assert (class != NULL); param_spec_follow_override (&pspec); if (user_specified) consider_issuing_property_deprecation_warning (pspec); pclass = G_PARAM_SPEC_GET_CLASS (pspec); if (g_value_type_compatible (G_VALUE_TYPE (value), pspec->value_type) && (pclass->value_validate == NULL || (pclass->value_is_valid != NULL && pclass->value_is_valid (pspec, value)))) { class->set_property (object, param_id, value, pspec); } else { /* provide a copy to work from, convert (if necessary) and validate */ GValue tmp_value = G_VALUE_INIT; g_value_init (&tmp_value, pspec->value_type); if (!g_value_transform (value, &tmp_value)) g_critical ("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_critical ("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 { class->set_property (object, param_id, &tmp_value, pspec); } g_value_unset (&tmp_value); } if ((pspec->flags & (G_PARAM_EXPLICIT_NOTIFY | G_PARAM_READABLE)) == G_PARAM_READABLE && nqueue != NULL) g_object_notify_queue_add (object, nqueue, pspec); } static void object_interface_check_properties (gpointer check_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 (class == NULL) return; if (!G_IS_OBJECT_CLASS (class)) goto out; 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 correctly. * * 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 * time 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); out: 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. Any * private data for the object is guaranteed to be initialized with zeros, as * per g_type_create_instance(). * * Note that in C, small integer types in variable argument lists are promoted * up to `gint` or `guint` as appropriate, and read back accordingly. `gint` is * 32 bits on every platform on which GLib is currently supported. This means that * you can use C expressions of type `gint` with g_object_new() and properties of * type `gint` or `guint` or smaller. Specifically, you can use integer literals * with these property types. * * When using property types of `gint64` or `guint64`, you must ensure that the * value that you provide is 64 bit. This means that you should use a cast or * make use of the %G_GINT64_CONSTANT or %G_GUINT64_CONSTANT macros. * * Similarly, `gfloat` is promoted to `gdouble`, so you must ensure that the value * you provide is a `gdouble`, even for a property of type `gfloat`. * * Since GLib 2.72, all #GObjects are guaranteed to be aligned to at least the * alignment of the largest basic GLib type (typically this is `guint64` or * `gdouble`). If you need larger alignment for an element in a #GObject, you * should allocate it on the heap (aligned), or arrange for your #GObject to be * appropriately padded. * * Returns: (transfer full) (type GObject.Object): a new instance of * @object_type */ gpointer g_object_new (GType object_type, const gchar *first_property_name, ...) { GObject *object; va_list var_args; /* short circuit for calls supplying no properties */ if (!first_property_name) return g_object_new_with_properties (object_type, 0, NULL, 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; } /* Check alignment. (See https://gitlab.gnome.org/GNOME/glib/-/issues/1231.) * This should never fail, since g_type_create_instance() uses g_slice_alloc0(). * The GSlice allocator always aligns to the next power of 2 greater than the * allocation size. The allocation size for a GObject is * sizeof(GTypeInstance) + sizeof(guint) + sizeof(GData*) * which is 12B on 32-bit platforms, and larger on 64-bit systems. In both * cases, that’s larger than the 8B needed for a guint64 or gdouble. * * If GSlice falls back to malloc(), it’s documented to return something * suitably aligned for any basic type. */ static inline gboolean g_object_is_aligned (GObject *object) { return ((((guintptr) (void *) object) % MAX (G_ALIGNOF (gdouble), MAX (G_ALIGNOF (guint64), MAX (G_ALIGNOF (gint), G_ALIGNOF (glong))))) == 0); } static gpointer g_object_new_with_custom_constructor (GObjectClass *class, GObjectConstructParam *params, guint n_params) { GObjectNotifyQueue *nqueue = NULL; gboolean newly_constructed; GObjectConstructParam *cparams; gboolean free_cparams = FALSE; GObject *object; GValue *cvalues; gint cvals_used; GSList *node; guint i; /* If we have ->constructed() then we have to do a lot more work. * It's possible that this is a singleton and it's also possible * that the user's constructor() will attempt to modify the values * that we pass in, so we'll need to allocate copies of them. * It's also possible that the user may attempt to call * g_object_set() from inside of their constructor, so we need to * add ourselves to a list of objects for which that is allowed * while their constructor() is running. */ /* Create the array of GObjectConstructParams for constructor(), * The 1024 here is an arbitrary, high limit that no sane code * will ever hit, just to avoid the possibility of stack overflow. */ if (G_LIKELY (class->n_construct_properties < 1024)) { cparams = g_newa0 (GObjectConstructParam, class->n_construct_properties); cvalues = g_newa0 (GValue, class->n_construct_properties); } else { cparams = g_new0 (GObjectConstructParam, class->n_construct_properties); cvalues = g_new0 (GValue, class->n_construct_properties); free_cparams = TRUE; } cvals_used = 0; i = 0; /* As above, we may find the value in the passed-in params list. * * If we have the value passed in then we can use the GValue from * it directly because it is safe to modify. If we use the * default value from the class, we had better not pass that in * and risk it being modified, so we create a new one. * */ for (node = class->construct_properties; node; node = node->next) { GParamSpec *pspec; GValue *value; guint j; pspec = node->data; value = NULL; /* to silence gcc... */ for (j = 0; j < n_params; j++) if (params[j].pspec == pspec) { consider_issuing_property_deprecation_warning (pspec); value = params[j].value; break; } if (value == NULL) { value = &cvalues[cvals_used++]; g_value_init (value, pspec->value_type); g_param_value_set_default (pspec, value); } cparams[i].pspec = pspec; cparams[i].value = value; i++; } /* construct object from construction parameters */ object = class->constructor (class->g_type_class.g_type, class->n_construct_properties, cparams); /* free construction values */ while (cvals_used--) g_value_unset (&cvalues[cvals_used]); if (free_cparams) { g_free (cparams); g_free (cvalues); } /* There is code in the wild that relies on being able to return NULL * from its custom constructor. This was never a supported operation, * but since the code is already out there... */ if (object == NULL) { g_critical ("Custom constructor for class %s returned NULL (which is invalid). " "Please use GInitable instead.", G_OBJECT_CLASS_NAME (class)); return NULL; } if (!g_object_is_aligned (object)) { g_critical ("Custom constructor for class %s returned a non-aligned " "GObject (which is invalid since GLib 2.72). Assuming any " "code using this object doesn’t require it to be aligned. " "Please fix your constructor to align to the largest GLib " "basic type (typically gdouble or guint64).", G_OBJECT_CLASS_NAME (class)); } /* g_object_init() will have marked the object as being in-construction. * Check if the returned object still is so marked, or if this is an * already-existing singleton (in which case we should not do 'constructed'). */ newly_constructed = object_in_construction (object); if (newly_constructed) unset_object_in_construction (object); if (CLASS_HAS_PROPS (class)) { if ((newly_constructed && _g_object_has_notify_handler_X (object)) || _g_object_has_notify_handler (object)) { /* This may or may not have been setup in g_object_init(). * If it hasn't, we do it now. */ nqueue = g_datalist_id_get_data (&object->qdata, quark_notify_queue); if (!nqueue) nqueue = g_object_notify_queue_freeze (object, FALSE); } } /* run 'constructed' handler if there is a custom one */ if (newly_constructed && CLASS_HAS_CUSTOM_CONSTRUCTED (class)) class->constructed (object); /* set remaining properties */ for (i = 0; i < n_params; i++) if (!(params[i].pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))) object_set_property (object, params[i].pspec, params[i].value, nqueue, TRUE); /* If nqueue is non-NULL then we are frozen. Thaw it. */ if (nqueue) g_object_notify_queue_thaw (object, nqueue); return object; } static gpointer g_object_new_internal (GObjectClass *class, GObjectConstructParam *params, guint n_params) { GObjectNotifyQueue *nqueue = NULL; GObject *object; guint i; if G_UNLIKELY (CLASS_HAS_CUSTOM_CONSTRUCTOR (class)) return g_object_new_with_custom_constructor (class, params, n_params); object = (GObject *) g_type_create_instance (class->g_type_class.g_type); g_assert (g_object_is_aligned (object)); unset_object_in_construction (object); if (CLASS_HAS_PROPS (class)) { GSList *node; if (_g_object_has_notify_handler_X (object)) { /* This may or may not have been setup in g_object_init(). * If it hasn't, we do it now. */ nqueue = g_datalist_id_get_data (&object->qdata, quark_notify_queue); if (!nqueue) nqueue = g_object_notify_queue_freeze (object, FALSE); } /* We will set exactly n_construct_properties construct * properties, but they may come from either the class default * values or the passed-in parameter list. */ for (node = class->construct_properties; node; node = node->next) { const GValue *value; GParamSpec *pspec; guint j; gboolean user_specified = FALSE; pspec = node->data; value = NULL; /* to silence gcc... */ for (j = 0; j < n_params; j++) if (params[j].pspec == pspec) { value = params[j].value; user_specified = TRUE; break; } if (value == NULL) value = g_param_spec_get_default_value (pspec); object_set_property (object, pspec, value, nqueue, user_specified); } } /* run 'constructed' handler if there is a custom one */ if (CLASS_HAS_CUSTOM_CONSTRUCTED (class)) class->constructed (object); /* Set remaining properties. The construct properties will * already have been taken, so set only the non-construct ones. */ for (i = 0; i < n_params; i++) if (!(params[i].pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))) object_set_property (object, params[i].pspec, params[i].value, nqueue, TRUE); if (nqueue) g_object_notify_queue_thaw (object, nqueue); return object; } static inline gboolean g_object_new_is_valid_property (GType object_type, GParamSpec *pspec, const char *name, GObjectConstructParam *params, guint n_params) { guint i; if (G_UNLIKELY (pspec == NULL)) { g_critical ("%s: object class '%s' has no property named '%s'", G_STRFUNC, g_type_name (object_type), name); return FALSE; } if (G_UNLIKELY (~pspec->flags & G_PARAM_WRITABLE)) { g_critical ("%s: property '%s' of object class '%s' is not writable", G_STRFUNC, pspec->name, g_type_name (object_type)); return FALSE; } if (G_UNLIKELY (pspec->flags & (G_PARAM_CONSTRUCT | G_PARAM_CONSTRUCT_ONLY))) { for (i = 0; i < n_params; i++) if (params[i].pspec == pspec) break; if (G_UNLIKELY (i != n_params)) { g_critical ("%s: property '%s' for type '%s' cannot be set twice", G_STRFUNC, name, g_type_name (object_type)); return FALSE; } } return TRUE; } /** * g_object_new_with_properties: (skip) * @object_type: the object type to instantiate * @n_properties: the number of properties * @names: (array length=n_properties): the names of each property to be set * @values: (array length=n_properties): the values of each property to be set * * Creates a new instance of a #GObject subtype and sets its properties using * the provided arrays. Both arrays must have exactly @n_properties elements, * and the names and values correspond by index. * * Construction parameters (see %G_PARAM_CONSTRUCT, %G_PARAM_CONSTRUCT_ONLY) * which are not explicitly specified are set to their default values. * * Returns: (type GObject.Object) (transfer full): a new instance of * @object_type * * Since: 2.54 */ GObject * g_object_new_with_properties (GType object_type, guint n_properties, const char *names[], const GValue values[]) { GObjectClass *class, *unref_class = NULL; GObject *object; g_return_val_if_fail (G_TYPE_IS_OBJECT (object_type), NULL); /* Try to avoid thrashing the ref_count if we don't need to (since * it's a locked operation). */ class = g_type_class_peek_static (object_type); if (class == NULL) class = unref_class = g_type_class_ref (object_type); if (n_properties > 0) { guint i, count = 0; GObjectConstructParam *params; params = g_newa (GObjectConstructParam, n_properties); for (i = 0; i < n_properties; i++) { GParamSpec *pspec = find_pspec (class, names[i]); if (!g_object_new_is_valid_property (object_type, pspec, names[i], params, count)) continue; params[count].pspec = pspec; params[count].value = (GValue *) &values[i]; count++; } object = g_object_new_internal (class, params, count); } else object = g_object_new_internal (class, NULL, 0); if (unref_class != NULL) g_type_class_unref (unref_class); return object; } /** * 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. * * Returns: (type GObject.Object) (transfer full): a new instance of * @object_type * * Deprecated: 2.54: Use g_object_new_with_properties() instead. * deprecated. See #GParameter for more information. */ G_GNUC_BEGIN_IGNORE_DEPRECATIONS gpointer g_object_newv (GType object_type, guint n_parameters, GParameter *parameters) { GObjectClass *class, *unref_class = NULL; GObject *object; g_return_val_if_fail (G_TYPE_IS_OBJECT (object_type), NULL); g_return_val_if_fail (n_parameters == 0 || parameters != NULL, NULL); /* Try to avoid thrashing the ref_count if we don't need to (since * it's a locked operation). */ class = g_type_class_peek_static (object_type); if (!class) class = unref_class = g_type_class_ref (object_type); if (n_parameters) { GObjectConstructParam *cparams; guint i, j; cparams = g_newa (GObjectConstructParam, n_parameters); j = 0; for (i = 0; i < n_parameters; i++) { GParamSpec *pspec = find_pspec (class, parameters[i].name); if (!g_object_new_is_valid_property (object_type, pspec, parameters[i].name, cparams, j)) continue; cparams[j].pspec = pspec; cparams[j].value = ¶meters[i].value; j++; } object = g_object_new_internal (class, cparams, j); } else /* Fast case: no properties passed in. */ object = g_object_new_internal (class, NULL, 0); if (unref_class) g_type_class_unref (unref_class); return object; } G_GNUC_END_IGNORE_DEPRECATIONS /** * 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, *unref_class = NULL; GObject *object; g_return_val_if_fail (G_TYPE_IS_OBJECT (object_type), NULL); /* Try to avoid thrashing the ref_count if we don't need to (since * it's a locked operation). */ class = g_type_class_peek_static (object_type); if (!class) class = unref_class = g_type_class_ref (object_type); if (first_property_name) { GObjectConstructParam params_stack[16]; GValue values_stack[G_N_ELEMENTS (params_stack)]; GTypeValueTable *vtabs_stack[G_N_ELEMENTS (params_stack)]; const gchar *name; GObjectConstructParam *params = params_stack; GValue *values = values_stack; GTypeValueTable **vtabs = vtabs_stack; guint n_params = 0; guint n_params_alloc = G_N_ELEMENTS (params_stack); name = first_property_name; do { gchar *error = NULL; GParamSpec *pspec = find_pspec (class, name); if (!g_object_new_is_valid_property (object_type, pspec, name, params, n_params)) break; if (G_UNLIKELY (n_params == n_params_alloc)) { guint i; if (n_params_alloc == G_N_ELEMENTS (params_stack)) { n_params_alloc = G_N_ELEMENTS (params_stack) * 2u; params = g_new (GObjectConstructParam, n_params_alloc); values = g_new (GValue, n_params_alloc); vtabs = g_new (GTypeValueTable *, n_params_alloc); memcpy (params, params_stack, sizeof (GObjectConstructParam) * n_params); memcpy (values, values_stack, sizeof (GValue) * n_params); memcpy (vtabs, vtabs_stack, sizeof (GTypeValueTable *) * n_params); } else { n_params_alloc *= 2u; params = g_realloc (params, sizeof (GObjectConstructParam) * n_params_alloc); values = g_realloc (values, sizeof (GValue) * n_params_alloc); vtabs = g_realloc (vtabs, sizeof (GTypeValueTable *) * n_params_alloc); } for (i = 0; i < n_params; i++) params[i].value = &values[i]; } params[n_params].pspec = pspec; params[n_params].value = &values[n_params]; memset (&values[n_params], 0, sizeof (GValue)); G_VALUE_COLLECT_INIT2 (&values[n_params], vtabs[n_params], pspec->value_type, var_args, G_VALUE_NOCOPY_CONTENTS, &error); if (error) { g_critical ("%s: %s", G_STRFUNC, error); g_value_unset (&values[n_params]); g_free (error); break; } n_params++; } while ((name = va_arg (var_args, const gchar *))); object = g_object_new_internal (class, params, n_params); while (n_params--) { /* We open-code g_value_unset() here to avoid the * cost of looking up the GTypeValueTable again. */ if (vtabs[n_params]->value_free) vtabs[n_params]->value_free (params[n_params].value); } if (G_UNLIKELY (n_params_alloc != G_N_ELEMENTS (params_stack))) { g_free (params); g_free (values); g_free (vtabs); } } else /* Fast case: no properties passed in. */ object = g_object_new_internal (class, NULL, 0); if (unref_class) g_type_class_unref (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, TRUE); } 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 */ } static inline gboolean g_object_set_is_valid_property (GObject *object, GParamSpec *pspec, const char *property_name) { if (G_UNLIKELY (pspec == NULL)) { g_critical ("%s: object class '%s' has no property named '%s'", G_STRFUNC, G_OBJECT_TYPE_NAME (object), property_name); return FALSE; } if (G_UNLIKELY (!(pspec->flags & G_PARAM_WRITABLE))) { g_critical ("%s: property '%s' of object class '%s' is not writable", G_STRFUNC, pspec->name, G_OBJECT_TYPE_NAME (object)); return FALSE; } if (G_UNLIKELY (((pspec->flags & G_PARAM_CONSTRUCT_ONLY) && !object_in_construction (object)))) { g_critical ("%s: construct property \"%s\" for object '%s' can't be set after construction", G_STRFUNC, pspec->name, G_OBJECT_TYPE_NAME (object)); return FALSE; } return TRUE; } /** * g_object_setv: (skip) * @object: a #GObject * @n_properties: the number of properties * @names: (array length=n_properties): the names of each property to be set * @values: (array length=n_properties): the values of each property to be set * * Sets @n_properties properties for an @object. * Properties to be set will be taken from @values. All properties must be * valid. Warnings will be emitted and undefined behaviour may result if invalid * properties are passed in. * * Since: 2.54 */ void g_object_setv (GObject *object, guint n_properties, const gchar *names[], const GValue values[]) { guint i; GObjectNotifyQueue *nqueue = NULL; GParamSpec *pspec; GObjectClass *class; g_return_if_fail (G_IS_OBJECT (object)); if (n_properties == 0) return; g_object_ref (object); class = G_OBJECT_GET_CLASS (object); if (_g_object_has_notify_handler (object)) nqueue = g_object_notify_queue_freeze (object, FALSE); for (i = 0; i < n_properties; i++) { pspec = find_pspec (class, names[i]); if (!g_object_set_is_valid_property (object, pspec, names[i])) break; object_set_property (object, pspec, &values[i], nqueue, TRUE); } if (nqueue) g_object_notify_queue_thaw (object, nqueue); g_object_unref (object); } /** * 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 = NULL; const gchar *name; GObjectClass *class; g_return_if_fail (G_IS_OBJECT (object)); g_object_ref (object); if (_g_object_has_notify_handler (object)) nqueue = g_object_notify_queue_freeze (object, FALSE); class = G_OBJECT_GET_CLASS (object); name = first_property_name; while (name) { GValue value = G_VALUE_INIT; GParamSpec *pspec; gchar *error = NULL; GTypeValueTable *vtab; pspec = find_pspec (class, name); if (!g_object_set_is_valid_property (object, pspec, name)) break; G_VALUE_COLLECT_INIT2 (&value, vtab, pspec->value_type, var_args, G_VALUE_NOCOPY_CONTENTS, &error); if (error) { g_critical ("%s: %s", G_STRFUNC, error); g_free (error); g_value_unset (&value); break; } object_set_property (object, pspec, &value, nqueue, TRUE); /* We open-code g_value_unset() here to avoid the * cost of looking up the GTypeValueTable again. */ if (vtab->value_free) vtab->value_free (&value); name = va_arg (var_args, gchar*); } if (nqueue) g_object_notify_queue_thaw (object, nqueue); g_object_unref (object); } static inline gboolean g_object_get_is_valid_property (GObject *object, GParamSpec *pspec, const char *property_name) { if (G_UNLIKELY (pspec == NULL)) { g_critical ("%s: object class '%s' has no property named '%s'", G_STRFUNC, G_OBJECT_TYPE_NAME (object), property_name); return FALSE; } if (G_UNLIKELY (!(pspec->flags & G_PARAM_READABLE))) { g_critical ("%s: property '%s' of object class '%s' is not readable", G_STRFUNC, pspec->name, G_OBJECT_TYPE_NAME (object)); return FALSE; } return TRUE; } /** * g_object_getv: * @object: a #GObject * @n_properties: the number of properties * @names: (array length=n_properties): the names of each property to get * @values: (array length=n_properties): the values of each property to get * * Gets @n_properties properties for an @object. * Obtained properties will be set to @values. All properties must be valid. * Warnings will be emitted and undefined behaviour may result if invalid * properties are passed in. * * Since: 2.54 */ void g_object_getv (GObject *object, guint n_properties, const gchar *names[], GValue values[]) { guint i; GParamSpec *pspec; GObjectClass *class; g_return_if_fail (G_IS_OBJECT (object)); if (n_properties == 0) return; g_object_ref (object); class = G_OBJECT_GET_CLASS (object); memset (values, 0, n_properties * sizeof (GValue)); for (i = 0; i < n_properties; i++) { pspec = find_pspec (class, names[i]); if (!g_object_get_is_valid_property (object, pspec, names[i])) break; g_value_init (&values[i], pspec->value_type); object_get_property (object, pspec, &values[i]); } 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; GObjectClass *class; g_return_if_fail (G_IS_OBJECT (object)); g_object_ref (object); class = G_OBJECT_GET_CLASS (object); name = first_property_name; while (name) { GValue value = G_VALUE_INIT; GParamSpec *pspec; gchar *error; pspec = find_pspec (class, name); if (!g_object_get_is_valid_property (object, pspec, name)) 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_critical ("%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: (type GObject.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. * * The same caveats about passing integer literals as varargs apply as with * g_object_new(). In particular, any integer literals set as the values for * properties of type #gint64 or #guint64 must be 64 bits wide, using the * %G_GINT64_CONSTANT or %G_GUINT64_CONSTANT macros. * * Note that the "notify" signals are queued and only emitted (in * reverse order) after all properties have been set. See * g_object_freeze_notify(). */ 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: (type GObject.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(). * * Here is an example of using g_object_get() to get the contents * of three properties: an integer, a string and an object: * |[ * gint intval; * guint64 uint64val; * gchar *strval; * GObject *objval; * * g_object_get (my_object, * "int-property", &intval, * "uint64-property", &uint64val, * "str-property", &strval, * "obj-property", &objval, * NULL); * * // Do something with intval, uint64val, 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) { g_object_setv (object, 1, &property_name, value); } /** * 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. * * The @value can be: * * - an empty #GValue initialized by %G_VALUE_INIT, which will be * automatically initialized with the expected type of the property * (since GLib 2.60) * - a #GValue initialized with the expected type of the property * - a #GValue initialized with a type to which the expected type * of the property can be transformed * * 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 (value != NULL); g_object_ref (object); pspec = find_pspec (G_OBJECT_GET_CLASS (object), property_name); if (g_object_get_is_valid_property (object, pspec, property_name)) { GValue *prop_value, tmp_value = G_VALUE_INIT; if (G_VALUE_TYPE (value) == G_TYPE_INVALID) { /* zero-initialized value */ g_value_init (value, pspec->value_type); prop_value = value; } else if (G_VALUE_TYPE (value) == pspec->value_type) { /* auto-conversion of the callers value type */ g_value_reset (value); prop_value = value; } else if (!g_value_type_transformable (pspec->value_type, G_VALUE_TYPE (value))) { g_critical ("%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: (type GObject.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, G_CONNECT_DEFAULT) * - object-signal, object_signal: equivalent to g_signal_connect_object (..., G_CONNECT_DEFAULT) * - 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) (type GObject.Object): @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, G_CONNECT_DEFAULT); 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, G_CONNECT_DEFAULT); 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_critical ("%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: (type GObject.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_critical ("%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_critical ("%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_critical ("%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 disposed. 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 (g_atomic_int_get (&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_critical ("%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) (not optional): 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) (not optional): 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][floating-ref] 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][floating-ref] 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 GLib 2.56, the type of @object will be propagated to the return type * under the same conditions as for g_object_ref(). * * 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 (g_atomic_int_get (&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_take_ref: (skip) * @object: (type GObject.Object): a #GObject * * If @object is floating, sink it. Otherwise, do nothing. * * In other words, this function will convert a floating reference (if * present) into a full reference. * * Typically you want to use g_object_ref_sink() in order to * automatically do the correct thing with respect to floating or * non-floating references, but there is one specific scenario where * this function is helpful. * * The situation where this function is helpful is when creating an API * that allows the user to provide a callback function that returns a * GObject. We certainly want to allow the user the flexibility to * return a non-floating reference from this callback (for the case * where the object that is being returned already exists). * * At the same time, the API style of some popular GObject-based * libraries (such as Gtk) make it likely that for newly-created GObject * instances, the user can be saved some typing if they are allowed to * return a floating reference. * * Using this function on the return value of the user's callback allows * the user to do whichever is more convenient for them. The caller will * alway receives exactly one full reference to the value: either the * one that was returned in the first place, or a floating reference * that has been converted to a full reference. * * This function has an odd interaction when combined with * g_object_ref_sink() running at the same time in another thread on * the same #GObject instance. If g_object_ref_sink() runs first then * the result will be that the floating reference is converted to a hard * reference. If g_object_take_ref() runs first then the result will be * that the floating reference is converted to a hard reference and an * additional reference on top of that one is added. It is best to avoid * this situation. * * Since: 2.70 * * Returns: (type GObject.Object) (transfer full): @object */ gpointer g_object_take_ref (gpointer _object) { GObject *object = _object; g_return_val_if_fail (G_IS_OBJECT (object), object); g_return_val_if_fail (g_atomic_int_get (&object->ref_count) >= 1, object); floating_flag_handler (object, -1); return object; } /** * g_object_force_floating: * @object: a #GObject * * This function is intended for #GObject implementations to re-enforce * a [floating][floating-ref] 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 (g_atomic_int_get (&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); /* If another thread removed the toggle reference on the object, while * we were waiting here, there's nothing to notify. * So let's check again if the object has toggle reference and in case return. */ if (!OBJECT_HAS_TOGGLE_REF (object)) { G_UNLOCK (toggle_refs_mutex); return; } 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 (g_atomic_int_get (&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: (nullable): data to pass to @notify, or %NULL to * match any toggle refs with the @notify argument. * * 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 || data == NULL)) { 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_critical ("%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. * * Since GLib 2.56, if `GLIB_VERSION_MAX_ALLOWED` is 2.56 or greater, the type * of @object will be propagated to the return type (using the GCC typeof() * extension), so any casting the caller needs to do on the return type must be * explicit. * * Returns: (type GObject.Object) (transfer none): the same @object */ gpointer (g_object_ref) (gpointer _object) { GObject *object = _object; gint old_val; gboolean object_already_finalized; g_return_val_if_fail (G_IS_OBJECT (object), NULL); old_val = g_atomic_int_add (&object->ref_count, 1); object_already_finalized = (old_val <= 0); g_return_val_if_fail (!object_already_finalized, NULL); 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). * * If the pointer to the #GObject may be reused in future (for example, if it is * an instance variable of another object), it is recommended to clear the * pointer to %NULL rather than retain a dangling pointer to a potentially * invalid #GObject instance. Use g_clear_object() for this. */ void g_object_unref (gpointer _object) { GObject *object = _object; gint old_ref; g_return_if_fail (G_IS_OBJECT (object)); /* here we want to atomically do: if (ref_count>1) { ref_count--; return; } */ old_ref = g_atomic_int_get (&object->ref_count); retry_atomic_decrement1: while (old_ref > 1) { /* valid if last 2 refs are owned by this call to unref and the toggle_ref */ if (!g_atomic_int_compare_and_exchange_full ((int *)&object->ref_count, old_ref, old_ref - 1, &old_ref)) continue; 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 && OBJECT_HAS_TOGGLE_REF (object)) { /* The last ref being held in this case is owned by the toggle_ref */ toggle_refs_notify (object, TRUE); } return; } { GSList **weak_locations; GObjectNotifyQueue *nqueue; /* 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. * * Other GWeakRef's (weak locations) instead may still be added * before the object is finalized, but in such case we'll unset * them as part of the qdata removal. */ 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, if they're still set. */ weak_locations = g_datalist_id_remove_no_notify (&object->qdata, quark_weak_locations); g_clear_pointer (&weak_locations, weak_locations_free_unlocked); g_rw_lock_writer_unlock (&weak_locations_lock); } /* freeze the notification queue, so we don't accidentally emit * notifications during dispose() and finalize(). * * The notification queue stays frozen unless the instance acquires * a reference during dispose(), in which case we thaw it and * dispatch all the notifications. If the instance gets through * to finalize(), the notification queue gets automatically * drained when g_object_finalize() is reached and * the qdata is cleared. */ nqueue = g_object_notify_queue_freeze (object, FALSE); /* 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 */ old_ref = g_atomic_int_get ((int *)&object->ref_count); while (old_ref > 1) { /* valid if last 2 refs are owned by this call to unref and the toggle_ref */ if (!g_atomic_int_compare_and_exchange_full ((int *)&object->ref_count, old_ref, old_ref - 1, &old_ref)) continue; TRACE (GOBJECT_OBJECT_UNREF (object, G_TYPE_FROM_INSTANCE (object), old_ref)); /* emit all notifications that have been queued during dispose() */ g_object_notify_queue_thaw (object, nqueue); /* if we went from 2->1 we need to notify toggle refs if any */ if (old_ref == 2 && OBJECT_HAS_TOGGLE_REF (object) && g_atomic_int_get ((int *)&object->ref_count) == 1) { /* 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); g_datalist_id_set_data (&object->qdata, quark_weak_locations, NULL); /* decrement the last reference */ old_ref = g_atomic_int_add (&object->ref_count, -1); g_return_if_fail (old_ref > 0); 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))); GOBJECT_IF_DEBUG (OBJECTS, { gboolean was_present; /* catch objects not chaining finalize handlers */ G_LOCK (debug_objects); was_present = g_hash_table_remove (debug_objects_ht, object); G_UNLOCK (debug_objects); if (was_present) g_critical ("Object %p of type %s not finalized correctly.", object, G_OBJECT_TYPE_NAME (object)); }); g_type_free_instance ((GTypeInstance*) object); } else { /* The instance acquired a reference between dispose() and * finalize(), so we need to thaw the notification queue */ g_object_notify_queue_thaw (object, nqueue); } } } /** * 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. * * 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 (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) (nullable): 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: (nullable): An opaque user data pointer * * This sets an opaque, named pointer on an object. * The name is specified through a #GQuark (retrieved 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: (skip) * @object: the #GObject to store user data on * @quark: a #GQuark, naming the user data pointer * @dup_func: (nullable): function to dup the value * @user_data: (nullable): 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: (skip) * @object: the #GObject to store user data on * @quark: a #GQuark, naming the user data pointer * @oldval: (nullable): the old value to compare against * @newval: (nullable): the new value * @destroy: (nullable): a destroy notify for the new value * @old_destroy: (out) (optional): 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 registered destroy notify for it (passed out in @old_destroy). * It’s up to the caller to free this as needed, which may * or may not include using @old_destroy as sometimes replacement * should not destroy the object in the normal way. * * Returns: %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: (nullable): An opaque user data pointer * @destroy: (nullable): 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"); * // retrieve 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) (nullable): 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) (nullable): 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: (nullable): 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. * * Internally, the @key is converted to a #GQuark using g_quark_from_string(). * This means a copy of @key is kept permanently (even after @object has been * finalized) — so it is recommended to only use a small, bounded set of values * for @key in your program, to avoid the #GQuark storage growing unbounded. */ 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: (skip) * @object: the #GObject to store user data on * @key: a string, naming the user data pointer * @dup_func: (nullable): function to dup the value * @user_data: (nullable): 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: (skip) * @object: the #GObject to store user data on * @key: a string, naming the user data pointer * @oldval: (nullable): the old value to compare against * @newval: (nullable): the new value * @destroy: (nullable): a destroy notify for the new value * @old_destroy: (out) (optional): 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 registered destroy notify for it (passed out in @old_destroy). * It’s up to the caller to free this as needed, which may * or may not include using @old_destroy as sometimes replacement * should not destroy the object in the normal way. * * See g_object_set_data() for guidance on using a small, bounded set of values * for @key. * * Returns: %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: (nullable): data to associate with that key * @destroy: (nullable): 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) (nullable): 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) { g_clear_object ((GObject**) &value->data[0].v_pointer); } static void g_value_object_copy_value (const GValue *src_value, GValue *dest_value) { g_set_object ((GObject**) &dest_value->data[0].v_pointer, src_value->data[0].v_pointer); } 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; g_return_val_if_fail (object_p != NULL, 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) (nullable): 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)); if G_UNLIKELY (value->data[0].v_pointer == v_object) return; old = g_steal_pointer (&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 = g_object_ref (v_object); } g_clear_object (&old); } /** * g_value_set_object_take_ownership: (skip) * @value: a valid #GValue of %G_TYPE_OBJECT derived type * @v_object: (nullable): 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: (nullable): 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 caller’s 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)); g_clear_object ((GObject **) &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 = g_steal_pointer (&v_object); } } /** * 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) (nullable): 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) (nullable): 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: (type GObject.TypeInstance): the instance to connect to. * @detailed_signal: a string of the form "signal-name::detail". * @c_handler: the #GCallback to connect. * @gobject: (type GObject.Object) (nullable): 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 @gobject 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 (g_atomic_int_get (&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 floating): 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 (g_atomic_int_get (&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: (transfer floating): 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 (g_atomic_int_get (&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: (transfer floating): 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 (g_atomic_int_get (&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. * * A `GWeakRef` 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 (‘re-referencing’), any #GWeakRefs taken * before it was disposed will continue to point to %NULL. Any #GWeakRefs taken * during disposal and after re-referencing, or after disposal has returned due * to the re-referencing, will continue to point to the object until its refcount * goes back to zero, at which point they too will be invalidated. * * It is invalid to take a #GWeakRef on an object during #GObjectClass.dispose * without first having or creating a strong reference to the object. */ /** * g_weak_ref_init: (skip) * @weak_ref: (inout): uninitialized or empty location for a weak * reference * @object: (type GObject.Object) (nullable): 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; } static void weak_locations_free_unlocked (GSList **weak_locations) { if (*weak_locations) { GSList *weak_location; for (weak_location = *weak_locations; weak_location;) { GWeakRef *weak_ref_location = weak_location->data; weak_ref_location->priv.p = NULL; weak_location = g_slist_delete_link (weak_location, weak_location); } } g_free (weak_locations); } static void weak_locations_free (gpointer data) { GSList **weak_locations = data; g_rw_lock_writer_lock (&weak_locations_lock); weak_locations_free_unlocked (weak_locations); g_rw_lock_writer_unlock (&weak_locations_lock); } /** * g_weak_ref_set: (skip) * @weak_ref: location for a weak reference * @object: (type GObject.Object) (nullable): 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); if (weak_locations == NULL) { #ifndef G_DISABLE_ASSERT gboolean in_weak_refs_notify = g_datalist_id_get_data (&old_object->qdata, quark_weak_refs) == NULL; g_assert (in_weak_refs_notify); #endif /* G_DISABLE_ASSERT */ } else { *weak_locations = g_slist_remove (*weak_locations, weak_ref); if (!*weak_locations) { weak_locations_free_unlocked (weak_locations); g_datalist_id_remove_no_notify (&old_object->qdata, quark_weak_locations); } } } /* 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, weak_locations_free); } *weak_locations = g_slist_prepend (*weak_locations, weak_ref); } } g_rw_lock_writer_unlock (&weak_locations_lock); }