gobject/gvalue.h

   1 /* GObject - GLib Type, Object, Parameter and Signal Library
   2  * Copyright (C) 1997-1999, 2000-2001 Tim Janik and Red Hat, Inc.
   3  *
   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.
   8  *
   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.
  13  *
  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.
  18  *
  19  * gvalue.h: generic GValue functions
  20  */
  21 #if !defined (__GLIB_GOBJECT_H_INSIDE__) && !defined (GOBJECT_COMPILATION)
  22 #error "Only <glib-object.h> can be included directly."
  23 #endif
  24
  25 #ifndef __G_VALUE_H__
  26 #define __G_VALUE_H__
  27
  28 #include        <gobject/gtype.h>
  29
  30 G_BEGIN_DECLS
  31
  32 /* --- type macros --- */
  33 #define G_TYPE_IS_VALUE(type)           (g_type_check_is_value_type (type))
  34 #define G_IS_VALUE(value)               (G_TYPE_CHECK_VALUE (value))
  35 #define G_VALUE_TYPE(value)             (((GValue*) (value))->g_type)
  36 #define G_VALUE_TYPE_NAME(value)        (g_type_name (G_VALUE_TYPE (value)))
  37 #define G_VALUE_HOLDS(value,type)       (G_TYPE_CHECK_VALUE_TYPE ((value), (type)))
  38
  39
  40 /* --- typedefs & structures --- */
  41 typedef void (*GValueTransform) (const GValue *src_value,
  42                                  GValue       *dest_value);
  43 struct _GValue
  44 {
  45   /*< private >*/
  46   GType         g_type;
  47
  48   /* public for GTypeValueTable methods */
  49   union {
  50     gint        v_int;
  51     guint       v_uint;
  52     glong       v_long;
  53     gulong      v_ulong;
  54     gint64      v_int64;
  55     guint64     v_uint64;
  56     gfloat      v_float;
  57     gdouble     v_double;
  58     gpointer    v_pointer;
  59   } data[2];
  60 };
  61
  62
  63 /* --- prototypes --- */
  64 GValue*         g_value_init            (GValue       *value,
  65                                          GType         g_type);
  66 void            g_value_copy            (const GValue *src_value,
  67                                          GValue       *dest_value);
  68 GValue*         g_value_reset           (GValue       *value);
  69 void            g_value_unset           (GValue       *value);
  70 void            g_value_set_instance    (GValue       *value,
  71                                          gpointer      instance);
  72
  73
  74 /* --- private --- */
  75 gboolean        g_value_fits_pointer    (const GValue *value);
  76 gpointer        g_value_peek_pointer    (const GValue *value);
  77
  78
  79 /* --- implementation details --- */
  80 gboolean g_value_type_compatible        (GType           src_type,
  81                                          GType           dest_type);
  82 gboolean g_value_type_transformable     (GType           src_type,
  83                                          GType           dest_type);
  84 gboolean g_value_transform              (const GValue   *src_value,
  85                                          GValue         *dest_value);
  86 void    g_value_register_transform_func (GType           src_type,
  87                                          GType           dest_type,
  88                                          GValueTransform transform_func);
  89 #define G_VALUE_NOCOPY_CONTENTS         (1 << 27)
  90
  91
  92 G_END_DECLS
  93
  94 #endif /* __G_VALUE_H__ */