1 /* GObject - GLib Type, Object, Parameter and Signal Library
2 * Copyright (C) 1998-1999, 2000-2001 Tim Janik and Red Hat, Inc.
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General
15 * Public License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
17 * Boston, MA 02111-1307, USA.
19 #if !defined (__GLIB_GOBJECT_H_INSIDE__) && !defined (GOBJECT_COMPILATION)
20 #error "Only <glib-object.h> can be included directly."
34 * @type: A #GType value.
36 * The fundamental type which is the ancestor of @type.
37 * Fundamental types are types that serve as ultimate bases for the derived types,
38 * thus they are the roots of distinct inheritance hierarchies.
40 #define G_TYPE_FUNDAMENTAL(type) (g_type_fundamental (type))
42 * G_TYPE_FUNDAMENTAL_MAX:
44 * An integer constant that represents the number of identifiers reserved
45 * for types that are assigned at compile-time.
47 #define G_TYPE_FUNDAMENTAL_MAX (255 << G_TYPE_FUNDAMENTAL_SHIFT)
49 /* Constant fundamental types,
50 * introduced by g_type_init().
55 * An invalid #GType used as error return value in some functions which return
58 #define G_TYPE_INVALID G_TYPE_MAKE_FUNDAMENTAL (0)
62 * A fundamental type which is used as a replacement for the C
63 * <literal>void</literal> return type.
65 #define G_TYPE_NONE G_TYPE_MAKE_FUNDAMENTAL (1)
69 * The fundamental type from which all interfaces are derived.
71 #define G_TYPE_INTERFACE G_TYPE_MAKE_FUNDAMENTAL (2)
75 * The fundamental type corresponding to #gchar.
76 * The type designated by G_TYPE_CHAR is unconditionally an 8-bit signed integer.
77 * This may or may not be the same type a the C type "gchar".
79 #define G_TYPE_CHAR G_TYPE_MAKE_FUNDAMENTAL (3)
83 * The fundamental type corresponding to #guchar.
85 #define G_TYPE_UCHAR G_TYPE_MAKE_FUNDAMENTAL (4)
89 * The fundamental type corresponding to #gboolean.
91 #define G_TYPE_BOOLEAN G_TYPE_MAKE_FUNDAMENTAL (5)
95 * The fundamental type corresponding to #gint.
97 #define G_TYPE_INT G_TYPE_MAKE_FUNDAMENTAL (6)
101 * The fundamental type corresponding to #guint.
103 #define G_TYPE_UINT G_TYPE_MAKE_FUNDAMENTAL (7)
107 * The fundamental type corresponding to #glong.
109 #define G_TYPE_LONG G_TYPE_MAKE_FUNDAMENTAL (8)
113 * The fundamental type corresponding to #gulong.
115 #define G_TYPE_ULONG G_TYPE_MAKE_FUNDAMENTAL (9)
119 * The fundamental type corresponding to #gint64.
121 #define G_TYPE_INT64 G_TYPE_MAKE_FUNDAMENTAL (10)
125 * The fundamental type corresponding to #guint64.
127 #define G_TYPE_UINT64 G_TYPE_MAKE_FUNDAMENTAL (11)
131 * The fundamental type from which all enumeration types are derived.
133 #define G_TYPE_ENUM G_TYPE_MAKE_FUNDAMENTAL (12)
137 * The fundamental type from which all flags types are derived.
139 #define G_TYPE_FLAGS G_TYPE_MAKE_FUNDAMENTAL (13)
143 * The fundamental type corresponding to #gfloat.
145 #define G_TYPE_FLOAT G_TYPE_MAKE_FUNDAMENTAL (14)
149 * The fundamental type corresponding to #gdouble.
151 #define G_TYPE_DOUBLE G_TYPE_MAKE_FUNDAMENTAL (15)
155 * The fundamental type corresponding to nul-terminated C strings.
157 #define G_TYPE_STRING G_TYPE_MAKE_FUNDAMENTAL (16)
161 * The fundamental type corresponding to #gpointer.
163 #define G_TYPE_POINTER G_TYPE_MAKE_FUNDAMENTAL (17)
167 * The fundamental type from which all boxed types are derived.
169 #define G_TYPE_BOXED G_TYPE_MAKE_FUNDAMENTAL (18)
173 * The fundamental type from which all #GParamSpec types are derived.
175 #define G_TYPE_PARAM G_TYPE_MAKE_FUNDAMENTAL (19)
179 * The fundamental type for #GObject.
181 #define G_TYPE_OBJECT G_TYPE_MAKE_FUNDAMENTAL (20)
184 /* Reserved fundamental type numbers to create new fundamental
185 * type IDs with G_TYPE_MAKE_FUNDAMENTAL().
186 * Send email to gtk-devel-list@gnome.org for reservations.
189 * G_TYPE_FUNDAMENTAL_SHIFT:
191 * Shift value used in converting numbers to type IDs.
193 #define G_TYPE_FUNDAMENTAL_SHIFT (2)
195 * G_TYPE_MAKE_FUNDAMENTAL:
196 * @x: the fundamental type number.
198 * Get the type ID for the fundamental type number @x.
199 * Use g_type_fundamental_next() instead of this macro to create new fundamental
204 #define G_TYPE_MAKE_FUNDAMENTAL(x) ((GType) ((x) << G_TYPE_FUNDAMENTAL_SHIFT))
206 * G_TYPE_RESERVED_GLIB_FIRST:
208 * First fundamental type number to create a new fundamental type id with
209 * G_TYPE_MAKE_FUNDAMENTAL() reserved for GLib.
211 #define G_TYPE_RESERVED_GLIB_FIRST (21)
213 * G_TYPE_RESERVED_GLIB_LAST:
215 * Last fundamental type number reserved for GLib.
217 #define G_TYPE_RESERVED_GLIB_LAST (31)
219 * G_TYPE_RESERVED_BSE_FIRST:
221 * First fundamental type number to create a new fundamental type id with
222 * G_TYPE_MAKE_FUNDAMENTAL() reserved for BSE.
224 #define G_TYPE_RESERVED_BSE_FIRST (32)
226 * G_TYPE_RESERVED_BSE_LAST:
228 * Last fundamental type number reserved for BSE.
230 #define G_TYPE_RESERVED_BSE_LAST (48)
232 * G_TYPE_RESERVED_USER_FIRST:
234 * First available fundamental type number to create new fundamental
235 * type id with G_TYPE_MAKE_FUNDAMENTAL().
237 #define G_TYPE_RESERVED_USER_FIRST (49)
240 /* Type Checking Macros
243 * G_TYPE_IS_FUNDAMENTAL:
244 * @type: A #GType value.
246 * Checks if @type is a fundamental type.
248 * Returns: %TRUE on success.
250 #define G_TYPE_IS_FUNDAMENTAL(type) ((type) <= G_TYPE_FUNDAMENTAL_MAX)
253 * @type: A #GType value.
255 * Checks if @type is derived (or in object-oriented terminology:
256 * inherited) from another type (this holds true for all non-fundamental
259 * Returns: %TRUE on success.
261 #define G_TYPE_IS_DERIVED(type) ((type) > G_TYPE_FUNDAMENTAL_MAX)
263 * G_TYPE_IS_INTERFACE:
264 * @type: A #GType value.
266 * Checks if @type is an interface type.
267 * An interface type provides a pure API, the implementation
268 * of which is provided by another type (which is then said to conform
269 * to the interface). GLib interfaces are somewhat analogous to Java
270 * interfaces and C++ classes containing only pure virtual functions,
271 * with the difference that GType interfaces are not derivable (but see
272 * g_type_interface_add_prerequisite() for an alternative).
274 * Returns: %TRUE on success.
276 #define G_TYPE_IS_INTERFACE(type) (G_TYPE_FUNDAMENTAL (type) == G_TYPE_INTERFACE)
279 * @type: A #GType value.
281 * Checks if @type is a classed type.
283 * Returns: %TRUE on success.
285 #define G_TYPE_IS_CLASSED(type) (g_type_test_flags ((type), G_TYPE_FLAG_CLASSED))
287 * G_TYPE_IS_INSTANTIATABLE:
288 * @type: A #GType value.
290 * Checks if @type can be instantiated. Instantiation is the
291 * process of creating an instance (object) of this type.
293 * Returns: %TRUE on success.
295 #define G_TYPE_IS_INSTANTIATABLE(type) (g_type_test_flags ((type), G_TYPE_FLAG_INSTANTIATABLE))
297 * G_TYPE_IS_DERIVABLE:
298 * @type: A #GType value.
300 * Checks if @type is a derivable type. A derivable type can
301 * be used as the base class of a flat (single-level) class hierarchy.
303 * Returns: %TRUE on success.
305 #define G_TYPE_IS_DERIVABLE(type) (g_type_test_flags ((type), G_TYPE_FLAG_DERIVABLE))
307 * G_TYPE_IS_DEEP_DERIVABLE:
308 * @type: A #GType value.
310 * Checks if @type is a deep derivable type. A deep derivable type
311 * can be used as the base class of a deep (multi-level) class hierarchy.
313 * Returns: %TRUE on success.
315 #define G_TYPE_IS_DEEP_DERIVABLE(type) (g_type_test_flags ((type), G_TYPE_FLAG_DEEP_DERIVABLE))
317 * G_TYPE_IS_ABSTRACT:
318 * @type: A #GType value.
320 * Checks if @type is an abstract type. An abstract type can not be
321 * instantiated and is normally used as an abstract base class for
324 * Returns: %TRUE on success.
326 #define G_TYPE_IS_ABSTRACT(type) (g_type_test_flags ((type), G_TYPE_FLAG_ABSTRACT))
328 * G_TYPE_IS_VALUE_ABSTRACT:
329 * @type: A #GType value.
331 * Checks if @type is an abstract value type. An abstract value type introduces
332 * a value table, but can't be used for g_value_init() and is normally used as
333 * an abstract base type for derived value types.
335 * Returns: %TRUE on success.
337 #define G_TYPE_IS_VALUE_ABSTRACT(type) (g_type_test_flags ((type), G_TYPE_FLAG_VALUE_ABSTRACT))
339 * G_TYPE_IS_VALUE_TYPE:
340 * @type: A #GType value.
342 * Checks if @type is a value type and can be used with g_value_init().
344 * Returns: %TRUE on success.
346 #define G_TYPE_IS_VALUE_TYPE(type) (g_type_check_is_value_type (type))
348 * G_TYPE_HAS_VALUE_TABLE:
349 * @type: A #GType value.
351 * Checks if @type has a #GTypeValueTable.
353 * Returns: %TRUE on success.
355 #define G_TYPE_HAS_VALUE_TABLE(type) (g_type_value_table_peek (type) != NULL)
363 * A numerical value which represents the unique identifier of a registered
366 #if GLIB_SIZEOF_SIZE_T != GLIB_SIZEOF_LONG || !defined __cplusplus
368 #else /* for historic reasons, C++ links against gulong GTypes */
369 typedef gulong GType;
371 typedef struct _GValue GValue;
372 typedef union _GTypeCValue GTypeCValue;
373 typedef struct _GTypePlugin GTypePlugin;
374 typedef struct _GTypeClass GTypeClass;
375 typedef struct _GTypeInterface GTypeInterface;
376 typedef struct _GTypeInstance GTypeInstance;
377 typedef struct _GTypeInfo GTypeInfo;
378 typedef struct _GTypeFundamentalInfo GTypeFundamentalInfo;
379 typedef struct _GInterfaceInfo GInterfaceInfo;
380 typedef struct _GTypeValueTable GTypeValueTable;
381 typedef struct _GTypeQuery GTypeQuery;
384 /* Basic Type Structures
389 * An opaque structure used as the base of all classes.
399 * An opaque structure used as the base of all type instances.
401 struct _GTypeInstance
409 * An opaque structure used as the base of all interface types.
411 struct _GTypeInterface
414 GType g_type; /* iface type */
415 GType g_instance_type;
419 * @type: the #GType value of the type.
420 * @type_name: the name of the type.
421 * @class_size: the size of the class structure.
422 * @instance_size: the size of the instance structure.
424 * A structure holding information for a specific type. It is
425 * filled in by the g_type_query() function.
430 const gchar *type_name;
436 /* Casts, checks and accessors for structured types
437 * usage of these macros is reserved to type implementations only
441 * G_TYPE_CHECK_INSTANCE:
442 * @instance: Location of a #GTypeInstance structure.
444 * Checks if @instance is a valid #GTypeInstance structure,
445 * otherwise issues a warning and returns %FALSE.
447 * This macro should only be used in type implementations.
449 * Returns: %TRUE on success.
451 #define G_TYPE_CHECK_INSTANCE(instance) (_G_TYPE_CHI ((GTypeInstance*) (instance)))
453 * G_TYPE_CHECK_INSTANCE_CAST:
454 * @instance: Location of a #GTypeInstance structure.
455 * @g_type: The type to be returned.
456 * @c_type: The corresponding C type of @g_type.
458 * Checks that @instance is an instance of the type identified by @g_type
459 * and issues a warning if this is not the case. Returns @instance casted
460 * to a pointer to @c_type.
462 * This macro should only be used in type implementations.
464 #define G_TYPE_CHECK_INSTANCE_CAST(instance, g_type, c_type) (_G_TYPE_CIC ((instance), (g_type), c_type))
466 * G_TYPE_CHECK_INSTANCE_TYPE:
467 * @instance: Location of a #GTypeInstance structure.
468 * @g_type: The type to be checked
470 * Checks if @instance is an instance of the type identified by @g_type.
472 * This macro should only be used in type implementations.
474 * Returns: %TRUE on success.
476 #define G_TYPE_CHECK_INSTANCE_TYPE(instance, g_type) (_G_TYPE_CIT ((instance), (g_type)))
478 * G_TYPE_INSTANCE_GET_CLASS:
479 * @instance: Location of the #GTypeInstance structure.
480 * @g_type: The #GType of the class to be returned.
481 * @c_type: The C type of the class structure.
483 * Get the class structure of a given @instance, casted
484 * to a specified ancestor type @g_type of the instance.
486 * Note that while calling a GInstanceInitFunc(), the class pointer gets
487 * modified, so it might not always return the expected pointer.
489 * This macro should only be used in type implementations.
491 * Returns: a pointer to the class structure
493 #define G_TYPE_INSTANCE_GET_CLASS(instance, g_type, c_type) (_G_TYPE_IGC ((instance), (g_type), c_type))
495 * G_TYPE_INSTANCE_GET_INTERFACE:
496 * @instance: Location of the #GTypeInstance structure.
497 * @g_type: The #GType of the interface to be returned.
498 * @c_type: The C type of the interface structure.
500 * Get the interface structure for interface @g_type of a given @instance.
502 * This macro should only be used in type implementations.
504 * Returns: a pointer to the interface structure
506 #define G_TYPE_INSTANCE_GET_INTERFACE(instance, g_type, c_type) (_G_TYPE_IGI ((instance), (g_type), c_type))
508 * G_TYPE_CHECK_CLASS_CAST:
509 * @g_class: Location of a #GTypeClass structure.
510 * @g_type: The type to be returned.
511 * @c_type: The corresponding C type of class structure of @g_type.
513 * Checks that @g_class is a class structure of the type identified by @g_type
514 * and issues a warning if this is not the case. Returns @g_class casted
515 * to a pointer to @c_type.
517 * This macro should only be used in type implementations.
519 #define G_TYPE_CHECK_CLASS_CAST(g_class, g_type, c_type) (_G_TYPE_CCC ((g_class), (g_type), c_type))
521 * G_TYPE_CHECK_CLASS_TYPE:
522 * @g_class: Location of a #GTypeClass structure.
523 * @g_type: The type to be checked.
525 * Checks if @g_class is a class structure of the type identified by
528 * This macro should only be used in type implementations.
530 * Returns: %TRUE on success.
532 #define G_TYPE_CHECK_CLASS_TYPE(g_class, g_type) (_G_TYPE_CCT ((g_class), (g_type)))
534 * G_TYPE_CHECK_VALUE:
537 * Checks if @value has been initialized to hold values
540 * This macro should only be used in type implementations.
542 * Returns: %TRUE on success.
544 #define G_TYPE_CHECK_VALUE(value) (_G_TYPE_CHV ((value)))
546 * G_TYPE_CHECK_VALUE_TYPE:
548 * @g_type: The type to be checked.
550 * Checks if @value has been initialized to hold values
553 * This macro should only be used in type implementations.
555 * Returns: %TRUE on success.
557 #define G_TYPE_CHECK_VALUE_TYPE(value, g_type) (_G_TYPE_CVH ((value), (g_type)))
559 * G_TYPE_FROM_INSTANCE:
560 * @instance: Location of a valid #GTypeInstance structure.
562 * Get the type identifier from a given @instance structure.
564 * This macro should only be used in type implementations.
566 * Returns: the #GType
568 #define G_TYPE_FROM_INSTANCE(instance) (G_TYPE_FROM_CLASS (((GTypeInstance*) (instance))->g_class))
571 * @g_class: Location of a valid #GTypeClass structure.
573 * Get the type identifier from a given @class structure.
575 * This macro should only be used in type implementations.
577 * Returns: the #GType
579 #define G_TYPE_FROM_CLASS(g_class) (((GTypeClass*) (g_class))->g_type)
581 * G_TYPE_FROM_INTERFACE:
582 * @g_iface: Location of a valid #GTypeInterface structure.
584 * Get the type identifier from a given @interface structure.
586 * This macro should only be used in type implementations.
588 * Returns: the #GType
590 #define G_TYPE_FROM_INTERFACE(g_iface) (((GTypeInterface*) (g_iface))->g_type)
593 * G_TYPE_INSTANCE_GET_PRIVATE:
594 * @instance: the instance of a type deriving from @private_type.
595 * @g_type: the type identifying which private data to retrieve.
596 * @c_type: The C type for the private structure.
598 * Gets the private structure for a particular type.
599 * The private structure must have been registered in the
600 * class_init function with g_type_class_add_private().
602 * This macro should only be used in type implementations.
605 * Returns: a pointer to the private data structure.
607 #define G_TYPE_INSTANCE_GET_PRIVATE(instance, g_type, c_type) ((c_type*) g_type_instance_get_private ((GTypeInstance*) (instance), (g_type)))
610 * G_TYPE_CLASS_GET_PRIVATE:
611 * @klass: the class of a type deriving from @private_type.
612 * @g_type: the type identifying which private data to retrieve.
613 * @c_type: The C type for the private structure.
615 * Gets the private class structure for a particular type.
616 * The private structure must have been registered in the
617 * get_type() function with g_type_add_class_private().
619 * This macro should only be used in type implementations.
622 * Returns: a pointer to the private data structure.
624 #define G_TYPE_CLASS_GET_PRIVATE(klass, g_type, c_type) ((c_type*) g_type_class_get_private ((GTypeClass*) (klass), (g_type)))
628 * @G_TYPE_DEBUG_NONE: Print no messages.
629 * @G_TYPE_DEBUG_OBJECTS: Print messages about object bookkeeping.
630 * @G_TYPE_DEBUG_SIGNALS: Print messages about signal emissions.
631 * @G_TYPE_DEBUG_MASK: Mask covering all debug flags.
633 * The <type>GTypeDebugFlags</type> enumeration values can be passed to
634 * g_type_init_with_debug_flags() to trigger debugging messages during runtime.
635 * Note that the messages can also be triggered by setting the
636 * <envar>GOBJECT_DEBUG</envar> environment variable to a ':'-separated list of
637 * "objects" and "signals".
639 typedef enum /*< skip >*/
641 G_TYPE_DEBUG_NONE = 0,
642 G_TYPE_DEBUG_OBJECTS = 1 << 0,
643 G_TYPE_DEBUG_SIGNALS = 1 << 1,
644 G_TYPE_DEBUG_MASK = 0x03
648 /* --- prototypes --- */
649 void g_type_init (void);
650 void g_type_init_with_debug_flags (GTypeDebugFlags debug_flags);
651 G_CONST_RETURN gchar* g_type_name (GType type);
652 GQuark g_type_qname (GType type);
653 GType g_type_from_name (const gchar *name);
654 GType g_type_parent (GType type);
655 guint g_type_depth (GType type);
656 GType g_type_next_base (GType leaf_type,
658 gboolean g_type_is_a (GType type,
660 gpointer g_type_class_ref (GType type);
661 gpointer g_type_class_peek (GType type);
662 gpointer g_type_class_peek_static (GType type);
663 void g_type_class_unref (gpointer g_class);
664 gpointer g_type_class_peek_parent (gpointer g_class);
665 gpointer g_type_interface_peek (gpointer instance_class,
667 gpointer g_type_interface_peek_parent (gpointer g_iface);
669 gpointer g_type_default_interface_ref (GType g_type);
670 gpointer g_type_default_interface_peek (GType g_type);
671 void g_type_default_interface_unref (gpointer g_iface);
673 /* g_free() the returned arrays */
674 GType* g_type_children (GType type,
676 GType* g_type_interfaces (GType type,
677 guint *n_interfaces);
679 /* per-type _static_ data */
680 void g_type_set_qdata (GType type,
683 gpointer g_type_get_qdata (GType type,
685 void g_type_query (GType type,
689 /* --- type registration --- */
692 * @g_class: The #GTypeClass structure to initialize.
694 * A callback function used by the type system to do base initialization
695 * of the class structures of derived types. It is called as part of the
696 * initialization process of all derived classes and should reallocate
697 * or reset all dynamic class members copied over from the parent class.
698 * For example, class members (such as strings) that are not sufficiently
699 * handled by a plain memory copy of the parent class into the derived class
700 * have to be altered. See GClassInitFunc() for a discussion of the class
701 * intialization process.
703 typedef void (*GBaseInitFunc) (gpointer g_class);
706 * @g_class: The #GTypeClass structure to finalize.
708 * A callback function used by the type system to finalize those portions
709 * of a derived types class structure that were setup from the corresponding
710 * GBaseInitFunc() function. Class finalization basically works the inverse
711 * way in which class intialization is performed.
712 * See GClassInitFunc() for a discussion of the class intialization process.
714 typedef void (*GBaseFinalizeFunc) (gpointer g_class);
717 * @g_class: The #GTypeClass structure to initialize.
718 * @class_data: The @class_data member supplied via the #GTypeInfo structure.
720 * A callback function used by the type system to initialize the class
721 * of a specific type. This function should initialize all static class
723 * The initialization process of a class involves:
726 * 1 - Copying common members from the parent class over to the
727 * derived class structure.
730 * 2 - Zero initialization of the remaining members not copied
731 * over from the parent class.
734 * 3 - Invocation of the GBaseInitFunc() initializers of all parent
735 * types and the class' type.
738 * 4 - Invocation of the class' GClassInitFunc() initializer.
741 * Since derived classes are partially initialized through a memory copy
742 * of the parent class, the general rule is that GBaseInitFunc() and
743 * GBaseFinalizeFunc() should take care of necessary reinitialization
744 * and release of those class members that were introduced by the type
745 * that specified these GBaseInitFunc()/GBaseFinalizeFunc().
746 * GClassInitFunc() should only care about initializing static
747 * class members, while dynamic class members (such as allocated strings
748 * or reference counted resources) are better handled by a GBaseInitFunc()
749 * for this type, so proper initialization of the dynamic class members
750 * is performed for class initialization of derived types as well.
751 * An example may help to correspond the intend of the different class
756 * GObjectClass parent_class;
757 * gint static_integer;
758 * gchar *dynamic_string;
761 * type_a_base_class_init (TypeAClass *class)
763 * class->dynamic_string = g_strdup ("some string");
766 * type_a_base_class_finalize (TypeAClass *class)
768 * g_free (class->dynamic_string);
771 * type_a_class_init (TypeAClass *class)
773 * class->static_integer = 42;
777 * TypeAClass parent_class;
778 * gfloat static_float;
779 * GString *dynamic_gstring;
782 * type_b_base_class_init (TypeBClass *class)
784 * class->dynamic_gstring = g_string_new ("some other string");
787 * type_b_base_class_finalize (TypeBClass *class)
789 * g_string_free (class->dynamic_gstring);
792 * type_b_class_init (TypeBClass *class)
794 * class->static_float = 3.14159265358979323846;
797 * Initialization of TypeBClass will first cause initialization of
798 * TypeAClass (derived classes reference their parent classes, see
799 * g_type_class_ref() on this).
800 * Initialization of TypeAClass roughly involves zero-initializing its fields,
801 * then calling its GBaseInitFunc() type_a_base_class_init() to allocate
802 * its dynamic members (dynamic_string), and finally calling its GClassInitFunc()
803 * type_a_class_init() to initialize its static members (static_integer).
804 * The first step in the initialization process of TypeBClass is then
805 * a plain memory copy of the contents of TypeAClass into TypeBClass and
806 * zero-initialization of the remaining fields in TypeBClass.
807 * The dynamic members of TypeAClass within TypeBClass now need
808 * reinitialization which is performed by calling type_a_base_class_init()
809 * with an argument of TypeBClass.
810 * After that, the GBaseInitFunc() of TypeBClass, type_b_base_class_init()
811 * is called to allocate the dynamic members of TypeBClass (dynamic_gstring),
812 * and finally the GClassInitFunc() of TypeBClass, type_b_class_init(),
813 * is called to complete the initialization process with the static members
815 * Corresponding finalization counter parts to the GBaseInitFunc() functions
816 * have to be provided to release allocated resources at class finalization
819 typedef void (*GClassInitFunc) (gpointer g_class,
820 gpointer class_data);
822 * GClassFinalizeFunc:
823 * @g_class: The #GTypeClass structure to finalize.
824 * @class_data: The @class_data member supplied via the #GTypeInfo structure.
826 * A callback function used by the type system to finalize a class.
827 * This function is rarely needed, as dynamically allocated class resources
828 * should be handled by GBaseInitFunc() and GBaseFinalizeFunc().
829 * Also, specification of a GClassFinalizeFunc() in the #GTypeInfo
830 * structure of a static type is invalid, because classes of static types
831 * will never be finalized (they are artificially kept alive when their
832 * reference count drops to zero).
834 typedef void (*GClassFinalizeFunc) (gpointer g_class,
835 gpointer class_data);
838 * @instance: The instance to initialize.
839 * @g_class: The class of the type the instance is created for.
841 * A callback function used by the type system to initialize a new
842 * instance of a type. This function initializes all instance members and
843 * allocates any resources required by it.
844 * Initialization of a derived instance involves calling all its parent
845 * types instance initializers, so the class member of the instance
846 * is altered during its initialization to always point to the class that
847 * belongs to the type the current initializer was introduced for.
849 typedef void (*GInstanceInitFunc) (GTypeInstance *instance,
852 * GInterfaceInitFunc:
853 * @g_iface: The interface structure to initialize.
854 * @iface_data: The @interface_data supplied via the #GInterfaceInfo structure.
856 * A callback function used by the type system to initialize a new
857 * interface. This function should initialize all internal data and
858 * allocate any resources required by the interface.
860 typedef void (*GInterfaceInitFunc) (gpointer g_iface,
861 gpointer iface_data);
863 * GInterfaceFinalizeFunc:
864 * @g_iface: The interface structure to finalize.
865 * @iface_data: The @interface_data supplied via the #GInterfaceInfo structure.
867 * A callback function used by the type system to finalize an interface.
868 * This function should destroy any internal data and release any resources
869 * allocated by the corresponding GInterfaceInitFunc() function.
871 typedef void (*GInterfaceFinalizeFunc) (gpointer g_iface,
872 gpointer iface_data);
874 * GTypeClassCacheFunc:
875 * @cache_data: data that was given to the g_type_add_class_cache_func() call
876 * @g_class: The #GTypeClass structure which is unreferenced
878 * A callback function which is called when the reference count of a class
879 * drops to zero. It may use g_type_class_ref() to prevent the class from
880 * being freed. You should not call g_type_class_unref() from a
881 * #GTypeClassCacheFunc function to prevent infinite recursion, use
882 * g_type_class_unref_uncached() instead.
884 * The functions have to check the class id passed in to figure
885 * whether they actually want to cache the class of this type, since all
886 * classes are routed through the same #GTypeClassCacheFunc chain.
888 * Returns: %TRUE to stop further #GTypeClassCacheFunc<!-- -->s from being
889 * called, %FALSE to continue.
891 typedef gboolean (*GTypeClassCacheFunc) (gpointer cache_data,
892 GTypeClass *g_class);
894 * GTypeInterfaceCheckFunc:
895 * @check_data: data passed to g_type_add_interface_check().
896 * @g_iface: the interface that has been initialized
898 * A callback called after an interface vtable is initialized.
899 * See g_type_add_interface_check().
903 typedef void (*GTypeInterfaceCheckFunc) (gpointer check_data,
906 * GTypeFundamentalFlags:
907 * @G_TYPE_FLAG_CLASSED: Indicates a classed type.
908 * @G_TYPE_FLAG_INSTANTIATABLE: Indicates an instantiable type (implies classed).
909 * @G_TYPE_FLAG_DERIVABLE: Indicates a flat derivable type.
910 * @G_TYPE_FLAG_DEEP_DERIVABLE: Indicates a deep derivable type (implies derivable).
912 * Bit masks used to check or determine specific characteristics of a
915 typedef enum /*< skip >*/
917 G_TYPE_FLAG_CLASSED = (1 << 0),
918 G_TYPE_FLAG_INSTANTIATABLE = (1 << 1),
919 G_TYPE_FLAG_DERIVABLE = (1 << 2),
920 G_TYPE_FLAG_DEEP_DERIVABLE = (1 << 3)
921 } GTypeFundamentalFlags;
924 * @G_TYPE_FLAG_ABSTRACT: Indicates an abstract type. No instances can be
925 * created for an abstract type.
926 * @G_TYPE_FLAG_VALUE_ABSTRACT: Indicates an abstract value type, i.e. a type
927 * that introduces a value table, but can't be used for
930 * Bit masks used to check or determine characteristics of a type.
932 typedef enum /*< skip >*/
934 G_TYPE_FLAG_ABSTRACT = (1 << 4),
935 G_TYPE_FLAG_VALUE_ABSTRACT = (1 << 5)
939 * @class_size: Size of the class structure (required for interface, classed and instantiatable types).
940 * @base_init: Location of the base initialization function (optional).
941 * @base_finalize: Location of the base finalization function (optional).
942 * @class_init: Location of the class initialization function for
943 * classed and instantiatable types. Location of the default vtable
944 * inititalization function for interface types. (optional) This function
945 * is used both to fill in virtual functions in the class or default vtable,
946 * and to do type-specific setup such as registering signals and object
948 * @class_finalize: Location of the class finalization function for
949 * classed and instantiatable types. Location fo the default vtable
950 * finalization function for interface types. (optional)
951 * @class_data: User-supplied data passed to the class init/finalize functions.
952 * @instance_size: Size of the instance (object) structure (required for instantiatable types only).
953 * @n_preallocs: Prior to GLib 2.10, it specified the number of pre-allocated (cached) instances to reserve memory for (0 indicates no caching). Since GLib 2.10, it is ignored, since instances are allocated with the <link linkend="glib-Memory-Slices">slice allocator</link> now.
954 * @instance_init: Location of the instance initialization function (optional, for instantiatable types only).
955 * @value_table: A #GTypeValueTable function table for generic handling of GValues of this type (usually only
956 * useful for fundamental types).
958 * This structure is used to provide the type system with the information
959 * required to initialize and destruct (finalize) a type's class and
961 * The initialized structure is passed to the g_type_register_static() function
962 * (or is copied into the provided #GTypeInfo structure in the
963 * g_type_plugin_complete_type_info()). The type system will perform a deep
964 * copy of this structure, so its memory does not need to be persistent
965 * across invocation of g_type_register_static().
969 /* interface types, classed types, instantiated types */
972 GBaseInitFunc base_init;
973 GBaseFinalizeFunc base_finalize;
975 /* interface types, classed types, instantiated types */
976 GClassInitFunc class_init;
977 GClassFinalizeFunc class_finalize;
978 gconstpointer class_data;
980 /* instantiated types */
981 guint16 instance_size;
983 GInstanceInitFunc instance_init;
986 const GTypeValueTable *value_table;
989 * GTypeFundamentalInfo:
990 * @type_flags: #GTypeFundamentalFlags describing the characteristics of the fundamental type
992 * A structure that provides information to the type system which is
993 * used specifically for managing fundamental types.
995 struct _GTypeFundamentalInfo
997 GTypeFundamentalFlags type_flags;
1001 * @interface_init: location of the interface initialization function
1002 * @interface_finalize: location of the interface finalization function
1003 * @interface_data: user-supplied data passed to the interface init/finalize functions
1005 * A structure that provides information to the type system which is
1006 * used specifically for managing interface types.
1008 struct _GInterfaceInfo
1010 GInterfaceInitFunc interface_init;
1011 GInterfaceFinalizeFunc interface_finalize;
1012 gpointer interface_data;
1016 * @value_init: Default initialize @values contents by poking values
1017 * directly into the value->data array. The data array of
1018 * the #GValue passed into this function was zero-filled
1019 * with <function>memset()</function>, so no care has to
1020 * be taken to free any
1021 * old contents. E.g. for the implementation of a string
1022 * value that may never be %NULL, the implementation might
1025 * value->data[0].v_pointer = g_strdup ("");
1027 * @value_free: Free any old contents that might be left in the
1028 * data array of the passed in @value. No resources may
1029 * remain allocated through the #GValue contents after
1030 * this function returns. E.g. for our above string type:
1032 * // only free strings without a specific flag for static storage
1033 * if (!(value->data[1].v_uint & G_VALUE_NOCOPY_CONTENTS))
1034 * g_free (value->data[0].v_pointer);
1036 * @value_copy: @dest_value is a #GValue with zero-filled data section
1037 * and @src_value is a properly setup #GValue of same or
1039 * The purpose of this function is to copy the contents of
1040 * @src_value into @dest_value in a way, that even after
1041 * @src_value has been freed, the contents of @dest_value
1042 * remain valid. String type example:
1044 * dest_value->data[0].v_pointer = g_strdup (src_value->data[0].v_pointer);
1046 * @value_peek_pointer: If the value contents fit into a pointer, such as objects
1047 * or strings, return this pointer, so the caller can peek at
1048 * the current contents. To extend on our above string example:
1050 * return value->data[0].v_pointer;
1052 * @collect_format: A string format describing how to collect the contents of
1053 * this value bit-by-bit. Each character in the format represents
1054 * an argument to be collected, and the characters themselves indicate
1055 * the type of the argument. Currently supported arguments are:
1057 * <varlistentry><term /><listitem><para>
1058 * 'i' - Integers. passed as collect_values[].v_int.
1059 * </para></listitem></varlistentry>
1060 * <varlistentry><term /><listitem><para>
1061 * 'l' - Longs. passed as collect_values[].v_long.
1062 * </para></listitem></varlistentry>
1063 * <varlistentry><term /><listitem><para>
1064 * 'd' - Doubles. passed as collect_values[].v_double.
1065 * </para></listitem></varlistentry>
1066 * <varlistentry><term /><listitem><para>
1067 * 'p' - Pointers. passed as collect_values[].v_pointer.
1068 * </para></listitem></varlistentry>
1070 * It should be noted that for variable argument list construction,
1071 * ANSI C promotes every type smaller than an integer to an int, and
1072 * floats to doubles. So for collection of short int or char, 'i'
1073 * needs to be used, and for collection of floats 'd'.
1074 * @collect_value: The collect_value() function is responsible for converting the
1075 * values collected from a variable argument list into contents
1076 * suitable for storage in a GValue. This function should setup
1077 * @value similar to value_init(); e.g. for a string value that
1078 * does not allow %NULL pointers, it needs to either spew an error,
1079 * or do an implicit conversion by storing an empty string.
1080 * The @value passed in to this function has a zero-filled data
1081 * array, so just like for value_init() it is guaranteed to not
1082 * contain any old contents that might need freeing.
1083 * @n_collect_values is exactly the string length of @collect_format,
1084 * and @collect_values is an array of unions #GTypeCValue with
1085 * length @n_collect_values, containing the collected values
1086 * according to @collect_format.
1087 * @collect_flags is an argument provided as a hint by the caller.
1088 * It may contain the flag %G_VALUE_NOCOPY_CONTENTS indicating,
1089 * that the collected value contents may be considered "static"
1090 * for the duration of the @value lifetime.
1091 * Thus an extra copy of the contents stored in @collect_values is
1092 * not required for assignment to @value.
1093 * For our above string example, we continue with:
1095 * if (!collect_values[0].v_pointer)
1096 * value->data[0].v_pointer = g_strdup ("");
1097 * else if (collect_flags & G_VALUE_NOCOPY_CONTENTS)
1099 * value->data[0].v_pointer = collect_values[0].v_pointer;
1100 * // keep a flag for the value_free() implementation to not free this string
1101 * value->data[1].v_uint = G_VALUE_NOCOPY_CONTENTS;
1104 * value->data[0].v_pointer = g_strdup (collect_values[0].v_pointer);
1107 * It should be noted, that it is generally a bad idea to follow the
1108 * #G_VALUE_NOCOPY_CONTENTS hint for reference counted types. Due to
1109 * reentrancy requirements and reference count assertions performed
1110 * by the #GSignal code, reference counts should always be incremented
1111 * for reference counted contents stored in the value->data array.
1112 * To deviate from our string example for a moment, and taking a look
1113 * at an exemplary implementation for collect_value() of #GObject:
1115 * if (collect_values[0].v_pointer)
1117 * GObject *object = G_OBJECT (collect_values[0].v_pointer);
1118 * // never honour G_VALUE_NOCOPY_CONTENTS for ref-counted types
1119 * value->data[0].v_pointer = g_object_ref (object);
1123 * return g_strdup_printf ("Object passed as invalid NULL pointer");
1126 * The reference count for valid objects is always incremented,
1127 * regardless of @collect_flags. For invalid objects, the example
1128 * returns a newly allocated string without altering @value.
1129 * Upon success, collect_value() needs to return %NULL. If, however,
1130 * an error condition occurred, collect_value() may spew an
1131 * error by returning a newly allocated non-%NULL string, giving
1132 * a suitable description of the error condition.
1133 * The calling code makes no assumptions about the @value
1134 * contents being valid upon error returns, @value
1135 * is simply thrown away without further freeing. As such, it is
1136 * a good idea to not allocate #GValue contents, prior to returning
1137 * an error, however, collect_values() is not obliged to return
1138 * a correctly setup @value for error returns, simply because
1139 * any non-%NULL return is considered a fatal condition so further
1140 * program behaviour is undefined.
1141 * @lcopy_format: Format description of the arguments to collect for @lcopy_value,
1142 * analogous to @collect_format. Usually, @lcopy_format string consists
1143 * only of 'p's to provide lcopy_value() with pointers to storage locations.
1144 * @lcopy_value: This function is responsible for storing the @value contents into
1145 * arguments passed through a variable argument list which got
1146 * collected into @collect_values according to @lcopy_format.
1147 * @n_collect_values equals the string length of @lcopy_format,
1148 * and @collect_flags may contain %G_VALUE_NOCOPY_CONTENTS.
1149 * In contrast to collect_value(), lcopy_value() is obliged to
1150 * always properly support %G_VALUE_NOCOPY_CONTENTS.
1151 * Similar to collect_value() the function may prematurely abort
1152 * by returning a newly allocated string describing an error condition.
1153 * To complete the string example:
1155 * gchar **string_p = collect_values[0].v_pointer;
1157 * return g_strdup_printf ("string location passed as NULL");
1158 * if (collect_flags & G_VALUE_NOCOPY_CONTENTS)
1159 * *string_p = value->data[0].v_pointer;
1161 * *string_p = g_strdup (value->data[0].v_pointer);
1163 * And an illustrative version of lcopy_value() for
1164 * reference-counted types:
1166 * GObject **object_p = collect_values[0].v_pointer;
1168 * return g_strdup_printf ("object location passed as NULL");
1169 * if (!value->data[0].v_pointer)
1171 * else if (collect_flags & G_VALUE_NOCOPY_CONTENTS) // always honour
1172 * *object_p = value->data[0].v_pointer;
1174 * *object_p = g_object_ref (value->data[0].v_pointer);
1178 * The #GTypeValueTable provides the functions required by the #GValue implementation,
1179 * to serve as a container for values of a type.
1182 struct _GTypeValueTable
1184 void (*value_init) (GValue *value);
1185 void (*value_free) (GValue *value);
1186 void (*value_copy) (const GValue *src_value,
1187 GValue *dest_value);
1188 /* varargs functionality (optional) */
1189 gpointer (*value_peek_pointer) (const GValue *value);
1190 gchar *collect_format;
1191 gchar* (*collect_value) (GValue *value,
1192 guint n_collect_values,
1193 GTypeCValue *collect_values,
1194 guint collect_flags);
1195 gchar *lcopy_format;
1196 gchar* (*lcopy_value) (const GValue *value,
1197 guint n_collect_values,
1198 GTypeCValue *collect_values,
1199 guint collect_flags);
1201 GType g_type_register_static (GType parent_type,
1202 const gchar *type_name,
1203 const GTypeInfo *info,
1205 GType g_type_register_static_simple (GType parent_type,
1206 const gchar *type_name,
1208 GClassInitFunc class_init,
1209 guint instance_size,
1210 GInstanceInitFunc instance_init,
1213 GType g_type_register_dynamic (GType parent_type,
1214 const gchar *type_name,
1215 GTypePlugin *plugin,
1217 GType g_type_register_fundamental (GType type_id,
1218 const gchar *type_name,
1219 const GTypeInfo *info,
1220 const GTypeFundamentalInfo *finfo,
1222 void g_type_add_interface_static (GType instance_type,
1223 GType interface_type,
1224 const GInterfaceInfo *info);
1225 void g_type_add_interface_dynamic (GType instance_type,
1226 GType interface_type,
1227 GTypePlugin *plugin);
1228 void g_type_interface_add_prerequisite (GType interface_type,
1229 GType prerequisite_type);
1230 GType*g_type_interface_prerequisites (GType interface_type,
1231 guint *n_prerequisites);
1232 void g_type_class_add_private (gpointer g_class,
1233 gsize private_size);
1234 gpointer g_type_instance_get_private (GTypeInstance *instance,
1235 GType private_type);
1237 void g_type_add_class_private (GType class_type,
1238 gsize private_size);
1239 gpointer g_type_class_get_private (GTypeClass *klass,
1240 GType private_type);
1243 /* --- GType boilerplate --- */
1246 * @TN: The name of the new type, in Camel case.
1247 * @t_n: The name of the new type, in lowercase, with words
1249 * @T_P: The #GType of the parent type.
1251 * A convenience macro for type implementations, which declares a
1252 * class initialization function, an instance initialization function (see #GTypeInfo for information about
1253 * these) and a static variable named @t_n<!-- -->_parent_class pointing to the parent class. Furthermore, it defines
1254 * a *_get_type() function. See G_DEFINE_TYPE_EXTENDED() for an example.
1258 #define G_DEFINE_TYPE(TN, t_n, T_P) G_DEFINE_TYPE_EXTENDED (TN, t_n, T_P, 0, {})
1260 * G_DEFINE_TYPE_WITH_CODE:
1261 * @TN: The name of the new type, in Camel case.
1262 * @t_n: The name of the new type in lowercase, with words separated by '_'.
1263 * @T_P: The #GType of the parent type.
1264 * @_C_: Custom code that gets inserted in the *_get_type() function.
1266 * A convenience macro for type implementations.
1267 * Similar to G_DEFINE_TYPE(), but allows you to insert custom code into the
1268 * *_get_type() function, e.g. interface implementations via G_IMPLEMENT_INTERFACE().
1269 * See G_DEFINE_TYPE_EXTENDED() for an example.
1273 #define G_DEFINE_TYPE_WITH_CODE(TN, t_n, T_P, _C_) _G_DEFINE_TYPE_EXTENDED_BEGIN (TN, t_n, T_P, 0) {_C_;} _G_DEFINE_TYPE_EXTENDED_END()
1275 * G_DEFINE_ABSTRACT_TYPE:
1276 * @TN: The name of the new type, in Camel case.
1277 * @t_n: The name of the new type, in lowercase, with words
1279 * @T_P: The #GType of the parent type.
1281 * A convenience macro for type implementations.
1282 * Similar to G_DEFINE_TYPE(), but defines an abstract type.
1283 * See G_DEFINE_TYPE_EXTENDED() for an example.
1287 #define G_DEFINE_ABSTRACT_TYPE(TN, t_n, T_P) G_DEFINE_TYPE_EXTENDED (TN, t_n, T_P, G_TYPE_FLAG_ABSTRACT, {})
1289 * G_DEFINE_ABSTRACT_TYPE_WITH_CODE:
1290 * @TN: The name of the new type, in Camel case.
1291 * @t_n: The name of the new type, in lowercase, with words
1293 * @T_P: The #GType of the parent type.
1294 * @_C_: Custom code that gets inserted in the @type_name_get_type() function.
1296 * A convenience macro for type implementations.
1297 * Similar to G_DEFINE_TYPE_WITH_CODE(), but defines an abstract type and allows you to
1298 * insert custom code into the *_get_type() function, e.g. interface implementations
1299 * via G_IMPLEMENT_INTERFACE(). See G_DEFINE_TYPE_EXTENDED() for an example.
1303 #define G_DEFINE_ABSTRACT_TYPE_WITH_CODE(TN, t_n, T_P, _C_) _G_DEFINE_TYPE_EXTENDED_BEGIN (TN, t_n, T_P, G_TYPE_FLAG_ABSTRACT) {_C_;} _G_DEFINE_TYPE_EXTENDED_END()
1305 * G_DEFINE_TYPE_EXTENDED:
1306 * @TN: The name of the new type, in Camel case.
1307 * @t_n: The name of the new type, in lowercase, with words
1309 * @T_P: The #GType of the parent type.
1310 * @_f_: #GTypeFlags to pass to g_type_register_static()
1311 * @_C_: Custom code that gets inserted in the *_get_type() function.
1313 * The most general convenience macro for type implementations, on which
1314 * G_DEFINE_TYPE(), etc are based.
1317 * G_DEFINE_TYPE_EXTENDED (GtkGadget,
1321 * G_IMPLEMENT_INTERFACE (TYPE_GIZMO,
1322 * gtk_gadget_gizmo_init));
1326 * static void gtk_gadget_init (GtkGadget *self);
1327 * static void gtk_gadget_class_init (GtkGadgetClass *klass);
1328 * static gpointer gtk_gadget_parent_class = NULL;
1329 * static void gtk_gadget_class_intern_init (gpointer klass)
1331 * gtk_gadget_parent_class = g_type_class_peek_parent (klass);
1332 * gtk_gadget_class_init ((GtkGadgetClass*) klass);
1336 * gtk_gadget_get_type (void)
1338 * static volatile gsize g_define_type_id__volatile = 0;
1339 * if (g_once_init_enter (&g_define_type_id__volatile))
1341 * GType g_define_type_id =
1342 * g_type_register_static_simple (GTK_TYPE_WIDGET,
1343 * g_intern_static_string ("GtkGadget"),
1344 * sizeof (GtkGadgetClass),
1345 * (GClassInitFunc) gtk_gadget_class_intern_init,
1346 * sizeof (GtkGadget),
1347 * (GInstanceInitFunc) gtk_gadget_init,
1348 * (GTypeFlags) flags);
1350 * static const GInterfaceInfo g_implement_interface_info = {
1351 * (GInterfaceInitFunc) gtk_gadget_gizmo_init
1353 * g_type_add_interface_static (g_define_type_id, TYPE_GIZMO, &g_implement_interface_info);
1355 * g_once_init_leave (&g_define_type_id__volatile, g_define_type_id);
1357 * return g_define_type_id__volatile;
1360 * The only pieces which have to be manually provided are the definitions of
1361 * the instance and class structure and the definitions of the instance and
1362 * class init functions.
1366 #define G_DEFINE_TYPE_EXTENDED(TN, t_n, T_P, _f_, _C_) _G_DEFINE_TYPE_EXTENDED_BEGIN (TN, t_n, T_P, _f_) {_C_;} _G_DEFINE_TYPE_EXTENDED_END()
1369 * G_DEFINE_INTERFACE:
1370 * @TN: The name of the new type, in Camel case.
1371 * @t_n: The name of the new type, in lowercase, with words separated by '_'.
1372 * @T_P: The #GType of the prerequisite type for the interface, or 0
1373 * (%G_TYPE_INVALID) for no prerequisite type.
1375 * A convenience macro for #GTypeInterface definitions, which declares
1376 * a default vtable initialization function and defines a *_get_type()
1379 * The macro expects the interface initialization function to have the
1380 * name <literal>t_n ## _default_init</literal>, and the interface
1381 * structure to have the name <literal>TN ## Interface</literal>.
1385 #define G_DEFINE_INTERFACE(TN, t_n, T_P) G_DEFINE_INTERFACE_WITH_CODE(TN, t_n, T_P, ;)
1388 * G_DEFINE_INTERFACE_WITH_CODE:
1389 * @TN: The name of the new type, in Camel case.
1390 * @t_n: The name of the new type, in lowercase, with words separated by '_'.
1391 * @T_P: The #GType of the prerequisite type for the interface, or 0
1392 * (%G_TYPE_INVALID) for no prerequisite type.
1393 * @_C_: Custom code that gets inserted in the *_get_type() function.
1395 * A convenience macro for #GTypeInterface definitions. Similar to
1396 * G_DEFINE_INTERFACE(), but allows you to insert custom code into the
1397 * *_get_type() function, e.g. additional interface implementations
1398 * via G_IMPLEMENT_INTERFACE(), or additional prerequisite types. See
1399 * G_DEFINE_TYPE_EXTENDED() for a similar example using
1400 * G_DEFINE_TYPE_WITH_CODE().
1404 #define G_DEFINE_INTERFACE_WITH_CODE(TN, t_n, T_P, _C_) _G_DEFINE_INTERFACE_EXTENDED_BEGIN(TN, t_n, T_P) {_C_;} _G_DEFINE_INTERFACE_EXTENDED_END()
1407 * G_IMPLEMENT_INTERFACE:
1408 * @TYPE_IFACE: The #GType of the interface to add
1409 * @iface_init: The interface init function
1411 * A convenience macro to ease interface addition in the @_C_ section
1412 * of G_DEFINE_TYPE_WITH_CODE() or G_DEFINE_ABSTRACT_TYPE_WITH_CODE().
1413 * See G_DEFINE_TYPE_EXTENDED() for an example.
1415 * Note that this macro can only be used together with the G_DEFINE_TYPE_*
1416 * macros, since it depends on variable names from those macros.
1420 #define G_IMPLEMENT_INTERFACE(TYPE_IFACE, iface_init) { \
1421 const GInterfaceInfo g_implement_interface_info = { \
1422 (GInterfaceInitFunc) iface_init, NULL, NULL \
1424 g_type_add_interface_static (g_define_type_id, TYPE_IFACE, &g_implement_interface_info); \
1427 #define _G_DEFINE_TYPE_EXTENDED_BEGIN(TypeName, type_name, TYPE_PARENT, flags) \
1429 static void type_name##_init (TypeName *self); \
1430 static void type_name##_class_init (TypeName##Class *klass); \
1431 static gpointer type_name##_parent_class = NULL; \
1432 static void type_name##_class_intern_init (gpointer klass) \
1434 type_name##_parent_class = g_type_class_peek_parent (klass); \
1435 type_name##_class_init ((TypeName##Class*) klass); \
1439 type_name##_get_type (void) \
1441 static volatile gsize g_define_type_id__volatile = 0; \
1442 if (g_once_init_enter (&g_define_type_id__volatile)) \
1444 GType g_define_type_id = \
1445 g_type_register_static_simple (TYPE_PARENT, \
1446 g_intern_static_string (#TypeName), \
1447 sizeof (TypeName##Class), \
1448 (GClassInitFunc) type_name##_class_intern_init, \
1449 sizeof (TypeName), \
1450 (GInstanceInitFunc) type_name##_init, \
1451 (GTypeFlags) flags); \
1452 { /* custom code follows */
1453 #define _G_DEFINE_TYPE_EXTENDED_END() \
1454 /* following custom code */ \
1456 g_once_init_leave (&g_define_type_id__volatile, g_define_type_id); \
1458 return g_define_type_id__volatile; \
1459 } /* closes type_name##_get_type() */
1461 #define _G_DEFINE_INTERFACE_EXTENDED_BEGIN(TypeName, type_name, TYPE_PREREQ) \
1463 static void type_name##_default_init (TypeName##Interface *klass); \
1466 type_name##_get_type (void) \
1468 static volatile gsize g_define_type_id__volatile = 0; \
1469 if (g_once_init_enter (&g_define_type_id__volatile)) \
1471 GType g_define_type_id = \
1472 g_type_register_static_simple (G_TYPE_INTERFACE, \
1473 g_intern_static_string (#TypeName), \
1474 sizeof (TypeName##Interface), \
1475 (GClassInitFunc)type_name##_default_init, \
1477 (GInstanceInitFunc)NULL, \
1480 g_type_interface_add_prerequisite (g_define_type_id, TYPE_PREREQ); \
1481 { /* custom code follows */
1482 #define _G_DEFINE_INTERFACE_EXTENDED_END() \
1483 /* following custom code */ \
1485 g_once_init_leave (&g_define_type_id__volatile, g_define_type_id); \
1487 return g_define_type_id__volatile; \
1488 } /* closes type_name##_get_type() */
1490 /* --- protected (for fundamental type implementations) --- */
1491 GTypePlugin* g_type_get_plugin (GType type);
1492 GTypePlugin* g_type_interface_get_plugin (GType instance_type,
1493 GType interface_type);
1494 GType g_type_fundamental_next (void);
1495 GType g_type_fundamental (GType type_id);
1496 GTypeInstance* g_type_create_instance (GType type);
1497 void g_type_free_instance (GTypeInstance *instance);
1499 void g_type_add_class_cache_func (gpointer cache_data,
1500 GTypeClassCacheFunc cache_func);
1501 void g_type_remove_class_cache_func (gpointer cache_data,
1502 GTypeClassCacheFunc cache_func);
1503 void g_type_class_unref_uncached (gpointer g_class);
1505 void g_type_add_interface_check (gpointer check_data,
1506 GTypeInterfaceCheckFunc check_func);
1507 void g_type_remove_interface_check (gpointer check_data,
1508 GTypeInterfaceCheckFunc check_func);
1510 GTypeValueTable* g_type_value_table_peek (GType type);
1514 gboolean g_type_check_instance (GTypeInstance *instance) G_GNUC_PURE;
1515 GTypeInstance* g_type_check_instance_cast (GTypeInstance *instance,
1517 gboolean g_type_check_instance_is_a (GTypeInstance *instance,
1518 GType iface_type) G_GNUC_PURE;
1519 GTypeClass* g_type_check_class_cast (GTypeClass *g_class,
1521 gboolean g_type_check_class_is_a (GTypeClass *g_class,
1522 GType is_a_type) G_GNUC_PURE;
1523 gboolean g_type_check_is_value_type (GType type) G_GNUC_CONST;
1524 gboolean g_type_check_value (GValue *value) G_GNUC_PURE;
1525 gboolean g_type_check_value_holds (GValue *value,
1526 GType type) G_GNUC_PURE;
1527 gboolean g_type_test_flags (GType type,
1528 guint flags) G_GNUC_CONST;
1531 /* --- debugging functions --- */
1532 G_CONST_RETURN gchar* g_type_name_from_instance (GTypeInstance *instance);
1533 G_CONST_RETURN gchar* g_type_name_from_class (GTypeClass *g_class);
1536 /* --- internal functions --- */
1537 G_GNUC_INTERNAL void g_value_c_init (void); /* sync with gvalue.c */
1538 G_GNUC_INTERNAL void g_value_types_init (void); /* sync with gvaluetypes.c */
1539 G_GNUC_INTERNAL void g_enum_types_init (void); /* sync with genums.c */
1540 G_GNUC_INTERNAL void g_param_type_init (void); /* sync with gparam.c */
1541 G_GNUC_INTERNAL void g_boxed_type_init (void); /* sync with gboxed.c */
1542 G_GNUC_INTERNAL void g_object_type_init (void); /* sync with gobject.c */
1543 G_GNUC_INTERNAL void g_param_spec_types_init (void); /* sync with gparamspecs.c */
1544 G_GNUC_INTERNAL void g_value_transforms_init (void); /* sync with gvaluetransform.c */
1545 G_GNUC_INTERNAL void g_signal_init (void); /* sync with gsignal.c */
1548 /* --- implementation bits --- */
1549 #ifndef G_DISABLE_CAST_CHECKS
1550 # define _G_TYPE_CIC(ip, gt, ct) \
1551 ((ct*) g_type_check_instance_cast ((GTypeInstance*) ip, gt))
1552 # define _G_TYPE_CCC(cp, gt, ct) \
1553 ((ct*) g_type_check_class_cast ((GTypeClass*) cp, gt))
1554 #else /* G_DISABLE_CAST_CHECKS */
1555 # define _G_TYPE_CIC(ip, gt, ct) ((ct*) ip)
1556 # define _G_TYPE_CCC(cp, gt, ct) ((ct*) cp)
1557 #endif /* G_DISABLE_CAST_CHECKS */
1558 #define _G_TYPE_CHI(ip) (g_type_check_instance ((GTypeInstance*) ip))
1559 #define _G_TYPE_CHV(vl) (g_type_check_value ((GValue*) vl))
1560 #define _G_TYPE_IGC(ip, gt, ct) ((ct*) (((GTypeInstance*) ip)->g_class))
1561 #define _G_TYPE_IGI(ip, gt, ct) ((ct*) g_type_interface_peek (((GTypeInstance*) ip)->g_class, gt))
1563 # define _G_TYPE_CIT(ip, gt) (G_GNUC_EXTENSION ({ \
1564 GTypeInstance *__inst = (GTypeInstance*) ip; GType __t = gt; gboolean __r; \
1567 else if (__inst->g_class && __inst->g_class->g_type == __t) \
1570 __r = g_type_check_instance_is_a (__inst, __t); \
1573 # define _G_TYPE_CCT(cp, gt) (G_GNUC_EXTENSION ({ \
1574 GTypeClass *__class = (GTypeClass*) cp; GType __t = gt; gboolean __r; \
1577 else if (__class->g_type == __t) \
1580 __r = g_type_check_class_is_a (__class, __t); \
1583 # define _G_TYPE_CVH(vl, gt) (G_GNUC_EXTENSION ({ \
1584 GValue *__val = (GValue*) vl; GType __t = gt; gboolean __r; \
1587 else if (__val->g_type == __t) \
1590 __r = g_type_check_value_holds (__val, __t); \
1593 #else /* !__GNUC__ */
1594 # define _G_TYPE_CIT(ip, gt) (g_type_check_instance_is_a ((GTypeInstance*) ip, gt))
1595 # define _G_TYPE_CCT(cp, gt) (g_type_check_class_is_a ((GTypeClass*) cp, gt))
1596 # define _G_TYPE_CVH(vl, gt) (g_type_check_value_holds ((GValue*) vl, gt))
1597 #endif /* !__GNUC__ */
1599 * G_TYPE_FLAG_RESERVED_ID_BIT:
1601 * A bit in the type number that's supposed to be left untouched.
1603 #define G_TYPE_FLAG_RESERVED_ID_BIT ((GType) (1 << 0))
1604 extern GTypeDebugFlags _g_type_debug_flags;
1608 #endif /* __G_TYPE_H__ */