gobject/gparam.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  * 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 G_BEGIN_DECLS
  28
  29 /* --- type macros --- */
  30 #define G_TYPE_IS_PARAM(type)           (G_TYPE_FUNDAMENTAL (type) == G_TYPE_PARAM)
  31 #define G_PARAM_SPEC_TYPE(pspec)        (G_TYPE_FROM_INSTANCE (pspec))
  32 #define G_PARAM_SPEC_TYPE_NAME(pspec)   (g_type_name (G_PARAM_SPEC_TYPE (pspec)))
  33 #define G_PARAM_SPEC(pspec)             (G_TYPE_CHECK_INSTANCE_CAST ((pspec), G_TYPE_PARAM, GParamSpec))
  34 #define G_IS_PARAM_SPEC(pspec)          (G_TYPE_CHECK_INSTANCE_TYPE ((pspec), G_TYPE_PARAM))
  35 #define G_PARAM_SPEC_GET_CLASS(pspec)   (G_TYPE_INSTANCE_GET_CLASS ((pspec), G_TYPE_PARAM, GParamSpecClass))
  36 #define G_PARAM_SPEC_VALUE_TYPE(pspec)  (G_PARAM_SPEC (pspec)->value_type)
  37 #define G_VALUE_HOLDS_PARAM(value)      (G_TYPE_CHECK_VALUE_TYPE ((value), G_TYPE_PARAM))
  38
  39
  40 /* --- flags --- */
  41 typedef enum
  42 {
  43   G_PARAM_READABLE            = 1 << 0,
  44   G_PARAM_WRITABLE            = 1 << 1,
  45   G_PARAM_CONSTRUCT           = 1 << 2,
  46   G_PARAM_CONSTRUCT_ONLY      = 1 << 3,
  47   G_PARAM_LAX_VALIDATION      = 1 << 4,
  48   G_PARAM_PRIVATE             = 1 << 5
  49 } GParamFlags;
  50 #define G_PARAM_READWRITE       (G_PARAM_READABLE | G_PARAM_WRITABLE)
  51 #define G_PARAM_MASK            (0x000000ff)
  52 /* bits in the range 0xffffff00 are reserved for 3rd party usage */
  53 #define G_PARAM_USER_SHIFT      (8)
  54
  55
  56 /* --- typedefs & structures --- */
  57 typedef struct _GParamSpec      GParamSpec;
  58 typedef struct _GParamSpecClass GParamSpecClass;
  59 typedef struct _GParamSpecPool  GParamSpecPool;
  60 struct _GParamSpec
  61 {
  62   GTypeInstance  g_type_instance;
  63
  64   gchar         *name;
  65   gchar         *nick;
  66   gchar         *blurb;
  67   GParamFlags    flags;
  68   GType          value_type;
  69
  70   /*< private >*/
  71   GType          owner_type;
  72   GData         *qdata;
  73   guint          ref_count;
  74 };
  75 struct _GParamSpecClass
  76 {
  77   GTypeClass      g_type_class;
  78
  79   GType           value_type;
  80
  81   void          (*finalize)             (GParamSpec   *pspec);
  82
  83   /* GParam methods */
  84   void          (*value_set_default)    (GParamSpec   *pspec,
  85                                          GValue       *value);
  86   gboolean      (*value_validate)       (GParamSpec   *pspec,
  87                                          GValue       *value);
  88   gint          (*values_cmp)           (GParamSpec   *pspec,
  89                                          const GValue *value1,
  90                                          const GValue *value2);
  91 };
  92
  93
  94 /* --- prototypes --- */
  95 GParamSpec*     g_param_spec_ref                (GParamSpec    *pspec);
  96 void            g_param_spec_unref              (GParamSpec    *pspec);
  97 void            g_param_spec_sink               (GParamSpec    *pspec);
  98 gpointer        g_param_spec_get_qdata          (GParamSpec    *pspec,
  99                                                  GQuark         quark);
 100 void            g_param_spec_set_qdata          (GParamSpec    *pspec,
 101                                                  GQuark         quark,
 102                                                  gpointer       data);
 103 void            g_param_spec_set_qdata_full     (GParamSpec    *pspec,
 104                                                  GQuark         quark,
 105                                                  gpointer       data,
 106                                                  GDestroyNotify destroy);
 107 gpointer        g_param_spec_steal_qdata        (GParamSpec    *pspec,
 108                                                  GQuark         quark);
 109 void            g_param_value_set_default       (GParamSpec    *pspec,
 110                                                  GValue        *value);
 111 gboolean        g_param_value_defaults          (GParamSpec    *pspec,
 112                                                  GValue        *value);
 113 gboolean        g_param_value_validate          (GParamSpec    *pspec,
 114                                                  GValue        *value);
 115 gboolean        g_param_value_convert           (GParamSpec    *dest_value_spec,
 116                                                  const GValue  *src_value,
 117                                                  GValue        *dest_value,
 118                                                  gboolean       strict_validation);
 119 gint            g_param_values_cmp              (GParamSpec    *pspec,
 120                                                  const GValue  *value1,
 121                                                  const GValue  *value2);
 122 void            g_value_set_param               (GValue        *value,
 123                                                  GParamSpec    *param);
 124 GParamSpec*     g_value_get_param               (const GValue  *value);
 125 GParamSpec*     g_value_dup_param               (const GValue  *value);
 126
 127
 128 /* --- convenience functions --- */
 129 typedef struct _GParamSpecTypeInfo GParamSpecTypeInfo;
 130 struct _GParamSpecTypeInfo
 131 {
 132   /* type system portion */
 133   guint16         instance_size;                               /* obligatory */
 134   guint16         n_preallocs;                                 /* optional */
 135   void          (*instance_init)        (GParamSpec   *pspec); /* optional */
 136
 137   /* class portion */
 138   GType           value_type;                                  /* obligatory */
 139   void          (*finalize)             (GParamSpec   *pspec); /* optional */
 140   void          (*value_set_default)    (GParamSpec   *pspec,  /* recommended */
 141                                          GValue       *value);
 142   gboolean      (*value_validate)       (GParamSpec   *pspec,  /* optional */
 143                                          GValue       *value);
 144   gint          (*values_cmp)           (GParamSpec   *pspec,  /* recommended */
 145                                          const GValue *value1,
 146                                          const GValue *value2);
 147 };
 148 GType   g_param_type_register_static    (const gchar              *name,
 149                                          const GParamSpecTypeInfo *pspec_info);
 150
 151
 152 /* --- protected --- */
 153 gpointer        g_param_spec_internal           (GType          param_type,
 154                                                  const gchar   *name,
 155                                                  const gchar   *nick,
 156                                                  const gchar   *blurb,
 157                                                  GParamFlags    flags);
 158 GParamSpecPool* g_param_spec_pool_new           (gboolean       type_prefixing);
 159 void            g_param_spec_pool_insert        (GParamSpecPool *pool,
 160                                                  GParamSpec     *pspec,
 161                                                  GType           owner_type);
 162 void            g_param_spec_pool_remove        (GParamSpecPool *pool,
 163                                                  GParamSpec     *pspec);
 164 GParamSpec*     g_param_spec_pool_lookup        (GParamSpecPool *pool,
 165                                                  const gchar    *param_name,
 166                                                  GType           owner_type,
 167                                                  gboolean        walk_ancestors);
 168 GList*          g_param_spec_pool_list          (GParamSpecPool *pool,
 169                                                  GType           owner_type);
 170
 171
 172
 173 /* contracts:
 174  *
 175  * gboolean value_validate (GParamSpec *pspec,
 176  *                          GValue     *value):
 177  *      modify value contents in the least destructive way, so
 178  *      that it complies with pspec's requirements (i.e.
 179  *      according to minimum/maximum ranges etc...). return
 180  *      whether modification was necessary.
 181  *
 182  * gint values_cmp (GParamSpec   *pspec,
 183  *                  const GValue *value1,
 184  *                  const GValue *value2):
 185  *      return value1 - value2, i.e. <0 if value1 < value2,
 186  *      >0 if value1 > value2, and 0 otherwise (they are equal)
 187  */
 188
 189 G_END_DECLS
 190
 191 #endif /* __G_PARAM_H__ */