gobject/gparam.h

   1 /* GObject - GLib Type, Object, Parameter and Signal Library
   2  * Copyright (C) 1997, 1998, 1999, 2000 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  * gparam.h: GParamSpec base class implementation
  20  */
  21 #ifndef __G_PARAM_H__
  22 #define __G_PARAM_H__
  23
  24
  25 #include        <gobject/gvalue.h>
  26
  27
  28 #ifdef __cplusplus
  29 extern "C" {
  30 #endif /* __cplusplus */
  31
  32
  33 /* --- type macros --- */
  34 #define G_TYPE_IS_PARAM(type)           (G_TYPE_FUNDAMENTAL (type) == G_TYPE_PARAM)
  35 #define G_PARAM_SPEC_TYPE(pspec)        (G_TYPE_FROM_INSTANCE (pspec))
  36 #define G_PARAM_SPEC_TYPE_NAME(pspec)   (g_type_name (G_PARAM_SPEC_TYPE (pspec)))
  37 #define G_PARAM_SPEC(pspec)             (G_TYPE_CHECK_INSTANCE_CAST ((pspec), G_TYPE_PARAM, GParamSpec))
  38 #define G_IS_PARAM_SPEC(pspec)          (G_TYPE_CHECK_INSTANCE_TYPE ((pspec), G_TYPE_PARAM))
  39 #define G_PARAM_SPEC_GET_CLASS(pspec)   (G_TYPE_INSTANCE_GET_CLASS ((pspec), G_TYPE_PARAM, GParamSpecClass))
  40 #define G_IS_PARAM_VALUE(pspec, value)  (g_type_is_a (G_VALUE_TYPE (value), G_PARAM_SPEC_VALUE_TYPE (pspec))) /* FIXME */
  41 #define G_PARAM_SPEC_VALUE_TYPE(pspec)  (G_PARAM_SPEC_GET_CLASS (pspec)->value_type)
  42
  43
  44 /* --- flags --- */
  45 typedef enum
  46 {
  47   G_PARAM_READABLE            = 1 << 0,
  48   G_PARAM_WRITABLE            = 1 << 1,
  49   G_PARAM_MASK                = 0x000f,
  50   /* bits in the range 0xfff0 are reserved for 3rd party usage */
  51   G_PARAM_USER_MASK           = 0xfff0
  52 } GParamFlags;
  53
  54
  55 /* --- typedefs & structures --- */
  56 typedef struct _GParamSpecClass GParamSpecClass;
  57 typedef struct _GParamSpec      GParamSpec;
  58 struct _GParamSpecClass
  59 {
  60   GTypeClass      g_type_class;
  61
  62   GType           value_type;
  63
  64   void          (*finalize)             (GParamSpec   *pspec);
  65
  66   /* GParam methods */
  67   void          (*value_set_default)    (GParamSpec   *pspec,
  68                                          GValue       *value);
  69   gboolean      (*value_validate)       (GParamSpec   *pspec,
  70                                          GValue       *value);
  71   gint          (*values_cmp)           (GParamSpec   *pspec,
  72                                          const GValue *value1,
  73                                          const GValue *value2);
  74 };
  75 struct _GParamSpec
  76 {
  77   GTypeInstance  g_instance;
  78
  79   gchar         *name;
  80   gchar         *nick;
  81   gchar         *blurb;
  82   GParamFlags    flags;
  83
  84   /*< private >*/
  85   GType          owner_type;
  86   GData         *qdata;
  87   guint          ref_count;
  88 };
  89
  90
  91 /* --- prototypes --- */
  92 GParamSpec*     g_param_spec_ref                (GParamSpec    *pspec);
  93 void            g_param_spec_unref              (GParamSpec    *pspec);
  94 gpointer        g_param_spec_get_qdata          (GParamSpec    *pspec,
  95                                                  GQuark         quark);
  96 void            g_param_spec_set_qdata          (GParamSpec    *pspec,
  97                                                  GQuark         quark,
  98                                                  gpointer       data);
  99 void            g_param_spec_set_qdata_full     (GParamSpec    *pspec,
 100                                                  GQuark         quark,
 101                                                  gpointer       data,
 102                                                  GDestroyNotify destroy);
 103 gpointer        g_param_spec_steal_qdata        (GParamSpec    *pspec,
 104                                                  GQuark         quark);
 105 void            g_param_value_set_default       (GParamSpec    *pspec,
 106                                                  GValue        *value);
 107 gboolean        g_param_value_defaults          (GParamSpec    *pspec,
 108                                                  GValue        *value);
 109 gboolean        g_param_value_validate          (GParamSpec    *pspec,
 110                                                  GValue        *value);
 111 gint            g_param_values_cmp              (GParamSpec    *pspec,
 112                                                  const GValue  *value1,
 113                                                  const GValue  *value2);
 114
 115
 116 /* --- convenience functions --- */
 117 typedef struct _GParamSpecTypeInfo GParamSpecTypeInfo;
 118 struct _GParamSpecTypeInfo
 119 {
 120   /* type system portion */
 121   guint16         instance_size;                               /* obligatory */
 122   guint16         n_preallocs;                                 /* optional */
 123   void          (*instance_init)        (GParamSpec   *pspec); /* optional */
 124
 125   /* class portion */
 126   GType           value_type;                                  /* obligatory */
 127   void          (*finalize)             (GParamSpec   *pspec); /* optional */
 128   void          (*value_set_default)    (GParamSpec   *pspec,  /* recommended */
 129                                          GValue       *value);
 130   gboolean      (*value_validate)       (GParamSpec   *pspec,  /* optional */
 131                                          GValue       *value);
 132   gint          (*values_cmp)           (GParamSpec   *pspec,  /* recommended */
 133                                          const GValue *value1,
 134                                          const GValue *value2);
 135 };
 136 GType   g_param_type_register_static    (const gchar              *name,
 137                                          const GParamSpecTypeInfo *pspec_info);
 138
 139
 140 /* --- private --- */
 141 gpointer        g_param_spec_internal           (GType          param_type,
 142                                                  const gchar   *name,
 143                                                  const gchar   *nick,
 144                                                  const gchar   *blurb,
 145                                                  GParamFlags    flags);
 146 GHashTable*     g_param_spec_hash_table_new     (void);
 147 void            g_param_spec_hash_table_insert  (GHashTable    *hash_table,
 148                                                  GParamSpec    *pspec,
 149                                                  GType          owner_type);
 150 void            g_param_spec_hash_table_remove  (GHashTable    *hash_table,
 151                                                  GParamSpec    *pspec);
 152 GParamSpec*     g_param_spec_hash_table_lookup  (GHashTable    *hash_table,
 153                                                  const gchar   *param_name,
 154                                                  GType          owner_type,
 155                                                  gboolean       try_ancestors,
 156                                                  const gchar  **trailer);
 157
 158
 159 /* contracts:
 160  *
 161  * gboolean value_validate (GParamSpec *pspec,
 162  *                          GValue     *value):
 163  *      modify value contents in the least destructive way, so
 164  *      that it complies with pspec's requirements (i.e.
 165  *      according to minimum/maximum ranges etc...). return
 166  *      whether modification was necessary.
 167  *
 168  * gint values_cmp (GParamSpec   *pspec,
 169  *                  const GValue *value1,
 170  *                  const GValue *value2):
 171  *      return value1 - value2, i.e. <0 if value1 < value2,
 172  *      >0 if value1 > value2, and 0 otherwise (they are equal)
 173  */
 174
 175 #ifdef __cplusplus
 176 }
 177 #endif /* __cplusplus */
 178
 179 #endif /* __G_PARAM_H__ */