/* * Backport of G_DECLARE_FINAL_TYPE and G_DECLARE_DERIVABLE_TYPE to older * versions of GLib. * * Copied from gobject/gtype.h in GLib, as last changed in commit 6b948d9. */ /* GObject - GLib Type, Object, Parameter and Signal Library * Copyright (C) 1998-1999, 2000-2001 Tim Janik and Red Hat, Inc. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 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 . */ #ifndef MQ_G_TYPE_H #define MQ_G_TYPE_H #include #ifndef G_DECLARE_FINAL_TYPE /** * G_DECLARE_FINAL_TYPE: * @ModuleObjName: The name of the new type, in camel case (like GtkWidget) * @module_obj_name: The name of the new type in lowercase, with words * separated by '_' (like 'gtk_widget') * @MODULE: The name of the module, in all caps (like 'GTK') * @OBJ_NAME: The bare name of the type, in all caps (like 'WIDGET') * @ParentName: the name of the parent type, in camel case (like GtkWidget) * * A convenience macro for emitting the usual declarations in the header file for a type which is not (at the * present time) intended to be subclassed. * * You might use it in a header as follows: * * |[ * #ifndef _myapp_window_h_ * #define _myapp_window_h_ * * #include * * #define MY_APP_TYPE_WINDOW my_app_window_get_type () * G_DECLARE_FINAL_TYPE (MyAppWindow, my_app_window, MY_APP, WINDOW, GtkWindow) * * MyAppWindow * my_app_window_new (void); * * ... * * #endif * ]| * * This results in the following things happening: * * - the usual my_app_window_get_type() function is declared with a return type of #GType * * - the MyAppWindow types is defined as a typedef of struct _MyAppWindow. The struct itself is not * defined and should be defined from the .c file before G_DEFINE_TYPE() is used. * * - the MY_APP_WINDOW() cast is emitted as static inline function along with the MY_APP_IS_WINDOW() type * checking function * * - the MyAppWindowClass type is defined as a struct containing GtkWindowClass. This is done for the * convenience of the person defining the type and should not be considered to be part of the ABI. In * particular, without a firm declaration of the instance structure, it is not possible to subclass the type * and therefore the fact that the size of the class structure is exposed is not a concern and it can be * freely changed at any point in the future. * * - g_autoptr() support being added for your type, based on the type of your parent class * * You can only use this function if your parent type also supports g_autoptr(). * * Because the type macro (MY_APP_TYPE_WINDOW in the above example) is not a callable, you must continue to * manually define this as a macro for yourself. * * The declaration of the _get_type() function is the first thing emitted by the macro. This allows this macro * to be used in the usual way with export control and API versioning macros. * * If you want to declare your own class structure, use G_DECLARE_DERIVABLE_TYPE(). * * If you are writing a library, it is important to note that it is possible to convert a type from using * G_DECLARE_FINAL_TYPE() to G_DECLARE_DERIVABLE_TYPE() without breaking API or ABI. As a precaution, you * should therefore use G_DECLARE_FINAL_TYPE() until you are sure that it makes sense for your class to be * subclassed. Once a class structure has been exposed it is not possible to change its size or remove or * reorder items without breaking the API and/or ABI. * * Since: 2.44 **/ #define G_DECLARE_FINAL_TYPE(ModuleObjName, module_obj_name, MODULE, OBJ_NAME, ParentName) \ GType module_obj_name##_get_type (void); \ G_GNUC_BEGIN_IGNORE_DEPRECATIONS \ typedef struct _##ModuleObjName ModuleObjName; \ typedef struct { ParentName##Class parent_class; } ModuleObjName##Class; \ \ _GLIB_DEFINE_AUTOPTR_CHAINUP (ModuleObjName, ParentName) \ \ static inline ModuleObjName * MODULE##_##OBJ_NAME (gpointer ptr) { \ return G_TYPE_CHECK_INSTANCE_CAST (ptr, module_obj_name##_get_type (), ModuleObjName); } \ static inline gboolean MODULE##_IS_##OBJ_NAME (gpointer ptr) { \ return G_TYPE_CHECK_INSTANCE_TYPE (ptr, module_obj_name##_get_type ()); } \ G_GNUC_END_IGNORE_DEPRECATIONS #endif /* G_DECLARE_FINAL_TYPE */ #ifndef G_DECLARE_DERIVABLE_TYPE /** * G_DECLARE_DERIVABLE_TYPE: * @ModuleObjName: The name of the new type, in camel case (like GtkWidget) * @module_obj_name: The name of the new type in lowercase, with words * separated by '_' (like 'gtk_widget') * @MODULE: The name of the module, in all caps (like 'GTK') * @OBJ_NAME: The bare name of the type, in all caps (like 'WIDGET') * @ParentName: the name of the parent type, in camel case (like GtkWidget) * * A convenience macro for emitting the usual declarations in the header file for a type which will is intended * to be subclassed. * * You might use it in a header as follows: * * |[ * #ifndef _gtk_frobber_h_ * #define _gtk_frobber_h_ * * #define GTK_TYPE_FROBBER gtk_frobber_get_type () * GDK_AVAILABLE_IN_3_12 * G_DECLARE_DERIVABLE_TYPE (GtkFrobber, gtk_frobber, GTK, FROBBER, GtkWidget) * * struct _GtkFrobberClass * { * GtkWidgetClass parent_class; * * void (* handle_frob) (GtkFrobber *frobber, * guint n_frobs); * * gpointer padding[12]; * }; * * GtkWidget * gtk_frobber_new (void); * * ... * * #endif * ]| * * This results in the following things happening: * * - the usual gtk_frobber_get_type() function is declared with a return type of #GType * * - the GtkFrobber struct is created with GtkWidget as the first and only item. You are expected to use * a private structure from your .c file to store your instance variables. * * - the GtkFrobberClass type is defined as a typedef to struct _GtkFrobberClass, which is left undefined. * You should do this from the header file directly after you use the macro. * * - the GTK_FROBBER() and GTK_FROBBER_CLASS() casts are emitted as static inline functions along with * the GTK_IS_FROBBER() and GTK_IS_FROBBER_CLASS() type checking functions and GTK_FROBBER_GET_CLASS() * function. * * - g_autoptr() support being added for your type, based on the type of your parent class * * You can only use this function if your parent type also supports g_autoptr(). * * Because the type macro (GTK_TYPE_FROBBER in the above example) is not a callable, you must continue to * manually define this as a macro for yourself. * * The declaration of the _get_type() function is the first thing emitted by the macro. This allows this macro * to be used in the usual way with export control and API versioning macros. * * If you are writing a library, it is important to note that it is possible to convert a type from using * G_DECLARE_FINAL_TYPE() to G_DECLARE_DERIVABLE_TYPE() without breaking API or ABI. As a precaution, you * should therefore use G_DECLARE_FINAL_TYPE() until you are sure that it makes sense for your class to be * subclassed. Once a class structure has been exposed it is not possible to change its size or remove or * reorder items without breaking the API and/or ABI. If you want to declare your own class structure, use * G_DECLARE_DERIVABLE_TYPE(). If you want to declare a class without exposing the class or instance * structures, use G_DECLARE_FINAL_TYPE(). * * If you must use G_DECLARE_DERIVABLE_TYPE() you should be sure to include some padding at the bottom of your * class structure to leave space for the addition of future virtual functions. * * Since: 2.44 **/ #define G_DECLARE_DERIVABLE_TYPE(ModuleObjName, module_obj_name, MODULE, OBJ_NAME, ParentName) \ GType module_obj_name##_get_type (void); \ G_GNUC_BEGIN_IGNORE_DEPRECATIONS \ typedef struct _##ModuleObjName ModuleObjName; \ typedef struct _##ModuleObjName##Class ModuleObjName##Class; \ struct _##ModuleObjName { ParentName parent_instance; }; \ \ _GLIB_DEFINE_AUTOPTR_CHAINUP (ModuleObjName, ParentName) \ \ static inline ModuleObjName * MODULE##_##OBJ_NAME (gpointer ptr) { \ return G_TYPE_CHECK_INSTANCE_CAST (ptr, module_obj_name##_get_type (), ModuleObjName); } \ static inline ModuleObjName##Class * MODULE##_##OBJ_NAME##_CLASS (gpointer ptr) { \ return G_TYPE_CHECK_CLASS_CAST (ptr, module_obj_name##_get_type (), ModuleObjName##Class); } \ static inline gboolean MODULE##_IS_##OBJ_NAME (gpointer ptr) { \ return G_TYPE_CHECK_INSTANCE_TYPE (ptr, module_obj_name##_get_type ()); } \ static inline gboolean MODULE##_IS_##OBJ_NAME##_CLASS (gpointer ptr) { \ return G_TYPE_CHECK_CLASS_TYPE (ptr, module_obj_name##_get_type ()); } \ static inline ModuleObjName##Class * MODULE##_##OBJ_NAME##_GET_CLASS (gpointer ptr) { \ return G_TYPE_INSTANCE_GET_CLASS (ptr, module_obj_name##_get_type (), ModuleObjName##Class); } \ G_GNUC_END_IGNORE_DEPRECATIONS #endif /* G_DECLARE_DERIVABLE_TYPE */ #endif /* MQ_G_TYPE_H */