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Diffstat (limited to 'gtk/gtkobject.h')
| -rw-r--r-- | gtk/gtkobject.h | 250 |
1 files changed, 250 insertions, 0 deletions
diff --git a/gtk/gtkobject.h b/gtk/gtkobject.h new file mode 100644 index 0000000000..023bbbf0c3 --- /dev/null +++ b/gtk/gtkobject.h @@ -0,0 +1,250 @@ +/* GTK - The GIMP Toolkit + * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Library General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Library General Public License for more details. + * + * You should have received a copy of the GNU Library General Public + * License along with this library; if not, write to the Free + * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ +#ifndef __GTK_OBJECT_H__ +#define __GTK_OBJECT_H__ + + +#include <gtk/gtkenums.h> +#include <gtk/gtktypeutils.h> + + +#ifdef __cplusplus +extern "C" { +#endif /* __cplusplus */ + + +/* GtkObject only uses the first 3 bits of the "flags" field. + * They refer to the following flags. + * GtkWidget uses the remaining bits. Though this is a kinda nasty + * break up, it does make the size of GtkWidget smaller. + */ +enum +{ + GTK_NEED_DESTROY = 1 << 0, + GTK_BEING_DESTROYED = 1 << 1, + GTK_IN_CALL = 1 << 2 +}; + + +/* The debugging versions of the casting macros make sure the cast is "ok" + * before proceeding, but they are definately slower than their less + * careful counterparts as they involve no less than 3 function calls. + */ +#ifdef NDEBUG + +#define GTK_CHECK_CAST(obj,cast_type,cast) ((cast*) obj) +#define GTK_CHECK_CLASS_CAST(klass,cast_type,cast) ((cast*) klass) + +#else /* NDEBUG */ + +#define GTK_CHECK_CAST(obj,cast_type,cast) \ + ((cast*) gtk_object_check_cast ((GtkObject*) obj, cast_type)) + +#define GTK_CHECK_CLASS_CAST(klass,cast_type,cast) \ + ((cast*) gtk_object_check_class_cast ((GtkObjectClass*) klass, cast_type)) + +#endif /* NDEBUG */ + + +/* Determines whether 'obj' is a type of 'otype'. + */ +#define GTK_CHECK_TYPE(obj,otype) (gtk_type_is_a (((GtkObject*) obj)->klass->type, otype)) + + +/* Macro for casting a pointer to a GtkObject pointer. + */ +#define GTK_OBJECT(obj) GTK_CHECK_CAST (obj, gtk_object_get_type (), GtkObject) + +/* Macros for extracting various fields from GtkObject and + * GtkObjectClass. + */ +#define GTK_OBJECT_CLASS(klass) GTK_CHECK_CLASS_CAST (klass, gtk_object_get_type (), GtkObjectClass) +#define GTK_OBJECT_FLAGS(obj) (GTK_OBJECT (obj)->flags) +#define GTK_OBJECT_NEED_DESTROY(obj) (GTK_OBJECT_FLAGS (obj) & GTK_NEED_DESTROY) +#define GTK_OBJECT_BEING_DESTROYED(obj) (GTK_OBJECT_FLAGS (obj) & GTK_BEING_DESTROYED) +#define GTK_OBJECT_IN_CALL(obj) (GTK_OBJECT_FLAGS (obj) & GTK_IN_CALL) +#define GTK_OBJECT_DESTROY(obj) (GTK_OBJECT (obj)->klass->destroy) +#define GTK_OBJECT_TYPE(obj) (GTK_OBJECT (obj)->klass->type) +#define GTK_OBJECT_SIGNALS(obj) (GTK_OBJECT (obj)->klass->signals) +#define GTK_OBJECT_NSIGNALS(obj) (GTK_OBJECT (obj)->klass->signals) + +/* Macro for testing whether "obj" is of type GtkObject. + */ +#define GTK_IS_OBJECT(obj) GTK_CHECK_TYPE (obj, gtk_object_get_type ()) + +/* Macros for setting and clearing bits in the "flags" field of GtkObject. + */ +#define GTK_OBJECT_SET_FLAGS(obj,flag) (GTK_OBJECT_FLAGS (obj) |= (flag)) +#define GTK_OBJECT_UNSET_FLAGS(obj,flag) (GTK_OBJECT_FLAGS (obj) &= ~(flag)) + + +typedef struct _GtkObjectClass GtkObjectClass; + + +/* GtkObject is the base of the object hierarchy. It defines + * the few basic items that all derived classes contain. + */ +struct _GtkObject +{ + /* 32 bits of flags. GtkObject only uses 3 of these bits and + * GtkWidget uses the rest. This is done because structs are + * aligned on 4 or 8 byte boundaries. If bitfields were used + * both here and in GtkWidget much space would be wasted. + */ + guint32 flags; + + /* 16 bit reference count. "gtk_object_destroy" actually only + * destroys an object when its ref count is 0. (Decrementing + * a reference count of 0 is defined as a no-op). + */ + guint16 ref_count; + + /* A pointer to the objects class. This will actually point to + * the derived objects class struct (which will be derived from + * GtkObjectClass). + */ + GtkObjectClass *klass; + + /* The list of signal handlers and other data + * fields for this object. + */ + gpointer object_data; +}; + +/* GtkObjectClass is the base of the class hierarchy. It defines + * the basic necessities for the class mechanism to work. Namely, + * the "type", "signals" and "nsignals" fields. + */ +struct _GtkObjectClass +{ + /* The type identifier for the objects class. There is + * one unique identifier per class. + */ + guint type; + + /* The signals this object class handles. "signals" is an + * array of signal ID's. + */ + gint *signals; + + /* The number of signals listed in "signals". + */ + gint nsignals; + + /* The destroy function for objects. In one way ore another + * this is defined for all objects. If an object class overrides + * this method in order to perform class specific destruction + * then it should still call it after it is finished with its + * own cleanup. (See the destroy function for GtkWidget for + * an example of how to do this). + */ + void (* destroy) (GtkObject *object); +}; + + +/* Get the type identifier for GtkObject's. + */ +guint gtk_object_get_type (void); + +/* Append "signals" to those already defined in "class". + */ +void gtk_object_class_add_signals (GtkObjectClass *klass, + gint *signals, + gint nsignals); + +void gtk_object_ref (GtkObject *object); + +void gtk_object_unref (GtkObject *object); + +GtkObject* gtk_object_new (guint type, + ...); + +GtkObject* gtk_object_newv (guint type, + gint nargs, + GtkArg *args); + +void gtk_object_set (GtkObject *obj, + ...); + +void gtk_object_setv (GtkObject *obj, + gint nargs, + GtkArg *args); + +void gtk_object_add_arg_type (const char *arg_name, + GtkType arg_type); + +GtkType gtk_object_get_arg_type (const char *arg_name); + +/* Emit the "destroy" signal for "object". Normally it is + * permissible to emit a signal for an object instead of + * calling the corresponding convenience routine, however + * "gtk_object_destroy" should be called instead of emitting + * the signal manually as it checks to see if the object is + * currently handling another signal emittion (very likely) + * and sets the GTK_NEED_DESTROY flag which tells the object + * to be destroyed when it is done handling the signal emittion. + */ +void gtk_object_destroy (GtkObject *object); + +/* Set 'data' to the "object_data" field of the object. The + * data is indexed by the "key". If there is already data + * associated with "key" then the new data will replace it. + * If 'data' is NULL then this call is equivalent to + * 'gtk_object_remove_data'. + */ +void gtk_object_set_data (GtkObject *object, + const gchar *key, + gpointer data); + +/* Get the data associated with "key". + */ +gpointer gtk_object_get_data (GtkObject *object, + const gchar *key); + +/* Remove the data associated with "key". This call is + * equivalent to 'gtk_object_set_data' where 'data' is NULL. + */ +void gtk_object_remove_data (GtkObject *object, + const gchar *key); + +/* Set the "user_data" object data field of "object". It should + * be noted that this is no different than calling 'gtk_object_data_add' + * with a key of "user_data". It is merely provided as a convenience. + */ +void gtk_object_set_user_data (GtkObject *object, + gpointer data); + +/* Get the "user_data" object data field of "object". It should + * be noted that this is no different than calling 'gtk_object_data_find' + * with a key of "user_data". It is merely provided as a convenience. + */ +gpointer gtk_object_get_user_data (GtkObject *object); + +GtkObject* gtk_object_check_cast (GtkObject *obj, + GtkType cast_type); + +GtkObjectClass* gtk_object_check_class_cast (GtkObjectClass *klass, + GtkType cast_type); + + +#ifdef __cplusplus +} +#endif /* __cplusplus */ + + +#endif /* __GTK_OBJECT_H__ */ |