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 /* --- standard type macros --- */
  30 #define G_TYPE_IS_PARAM(type)           (G_TYPE_FUNDAMENTAL (type) == G_TYPE_PARAM)
  31 #define G_PARAM_SPEC(pspec)             (G_TYPE_CHECK_INSTANCE_CAST ((pspec), G_TYPE_PARAM, GParamSpec))
  32 #define G_IS_PARAM_SPEC(pspec)          (G_TYPE_CHECK_INSTANCE_TYPE ((pspec), G_TYPE_PARAM))
  33 #define G_PARAM_SPEC_CLASS(pclass)      (G_TYPE_CHECK_CLASS_CAST ((pclass), G_TYPE_PARAM, GParamSpecClass))
  34 #define G_IS_PARAM_SPEC_CLASS(pclass)   (G_TYPE_CHECK_CLASS_TYPE ((pclass), G_TYPE_PARAM))
  35 #define G_PARAM_SPEC_GET_CLASS(pspec)   (G_TYPE_INSTANCE_GET_CLASS ((pspec), G_TYPE_PARAM, GParamSpecClass))
  36
  37
  38 /* --- convenience macros --- */
  39 #define G_PARAM_SPEC_TYPE(pspec)        (G_TYPE_FROM_INSTANCE (pspec))
  40 #define G_PARAM_SPEC_TYPE_NAME(pspec)   (g_type_name (G_PARAM_SPEC_TYPE (pspec)))
  41 #define G_PARAM_SPEC_VALUE_TYPE(pspec)  (G_PARAM_SPEC (pspec)->value_type)
  42 #define G_VALUE_HOLDS_PARAM(value)      (G_TYPE_CHECK_VALUE_TYPE ((value), G_TYPE_PARAM))
  43
  44
  45 /* --- flags --- */
  46 typedef enum
  47 {
  48   G_PARAM_READABLE            = 1 << 0,
  49   G_PARAM_WRITABLE            = 1 << 1,
  50   G_PARAM_CONSTRUCT           = 1 << 2,
  51   G_PARAM_CONSTRUCT_ONLY      = 1 << 3,
  52   G_PARAM_LAX_VALIDATION      = 1 << 4,
  53   G_PARAM_PRIVATE             = 1 << 5
  54 } GParamFlags;
  55 #define G_PARAM_READWRITE       (G_PARAM_READABLE | G_PARAM_WRITABLE)
  56 #define G_PARAM_MASK            (0x000000ff)
  57 /* bits in the range 0xffffff00 are reserved for 3rd party usage */
  58 #define G_PARAM_USER_SHIFT      (8)
  59
  60
  61 /* --- typedefs & structures --- */
  62 typedef struct _GParamSpec      GParamSpec;
  63 typedef struct _GParamSpecClass GParamSpecClass;
  64 typedef struct _GParameter      GParameter;
  65 typedef struct _GParamSpecPool  GParamSpecPool;
  66 struct _GParamSpec
  67 {
  68   GTypeInstance  g_type_instance;
  69
  70   gchar         *name;
  71   GParamFlags    flags;
  72   GType          value_type;
  73   GType          owner_type;    /* class using this property */
  74
  75   /*< private >*/
  76   gchar         *_nick;
  77   gchar         *_blurb;
  78   GData         *qdata;
  79   guint          ref_count;
  80   guint          param_id;      /* sort-criteria */
  81 };
  82 struct _GParamSpecClass
  83 {
  84   GTypeClass      g_type_class;
  85
  86   GType           value_type;
  87
  88   void          (*finalize)             (GParamSpec   *pspec);
  89
  90   /* GParam methods */
  91   void          (*value_set_default)    (GParamSpec   *pspec,
  92                                          GValue       *value);
  93   gboolean      (*value_validate)       (GParamSpec   *pspec,
  94                                          GValue       *value);
  95   gint          (*values_cmp)           (GParamSpec   *pspec,
  96                                          const GValue *value1,
  97                                          const GValue *value2);
  98 };
  99 struct _GParameter /* auxillary structure for _setv() variants */
 100 {
 101   const gchar *name;
 102   GValue       value;
 103 };
 104
 105
 106 /* --- prototypes --- */
 107 GParamSpec*     g_param_spec_ref                (GParamSpec    *pspec);
 108 void            g_param_spec_unref              (GParamSpec    *pspec);
 109 void            g_param_spec_sink               (GParamSpec    *pspec);
 110 gpointer        g_param_spec_get_qdata          (GParamSpec    *pspec,
 111                                                  GQuark         quark);
 112 void            g_param_spec_set_qdata          (GParamSpec    *pspec,
 113                                                  GQuark         quark,
 114                                                  gpointer       data);
 115 void            g_param_spec_set_qdata_full     (GParamSpec    *pspec,
 116                                                  GQuark         quark,
 117                                                  gpointer       data,
 118                                                  GDestroyNotify destroy);
 119 gpointer        g_param_spec_steal_qdata        (GParamSpec    *pspec,
 120                                                  GQuark         quark);
 121 void            g_param_value_set_default       (GParamSpec    *pspec,
 122                                                  GValue        *value);
 123 gboolean        g_param_value_defaults          (GParamSpec    *pspec,
 124                                                  GValue        *value);
 125 gboolean        g_param_value_validate          (GParamSpec    *pspec,
 126                                                  GValue        *value);
 127 gboolean        g_param_value_convert           (GParamSpec    *pspec,
 128                                                  const GValue  *src_value,
 129                                                  GValue        *dest_value,
 130                                                  gboolean       strict_validation);
 131 gint            g_param_values_cmp              (GParamSpec    *pspec,
 132                                                  const GValue  *value1,
 133                                                  const GValue  *value2);
 134 G_CONST_RETURN gchar*   g_param_spec_get_name   (GParamSpec    *pspec);
 135 G_CONST_RETURN gchar*   g_param_spec_get_nick   (GParamSpec    *pspec);
 136 G_CONST_RETURN gchar*   g_param_spec_get_blurb  (GParamSpec    *pspec);
 137 void            g_value_set_param               (GValue        *value,
 138                                                  GParamSpec    *param);
 139 GParamSpec*     g_value_get_param               (const GValue  *value);
 140 GParamSpec*     g_value_dup_param               (const GValue  *value);
 141
 142
 143 /* --- convenience functions --- */
 144 typedef struct _GParamSpecTypeInfo GParamSpecTypeInfo;
 145 struct _GParamSpecTypeInfo
 146 {
 147   /* type system portion */
 148   guint16         instance_size;                               /* obligatory */
 149   guint16         n_preallocs;                                 /* optional */
 150   void          (*instance_init)        (GParamSpec   *pspec); /* optional */
 151
 152   /* class portion */
 153   GType           value_type;                                  /* obligatory */
 154   void          (*finalize)             (GParamSpec   *pspec); /* optional */
 155   void          (*value_set_default)    (GParamSpec   *pspec,  /* recommended */
 156                                          GValue       *value);
 157   gboolean      (*value_validate)       (GParamSpec   *pspec,  /* optional */
 158                                          GValue       *value);
 159   gint          (*values_cmp)           (GParamSpec   *pspec,  /* recommended */
 160                                          const GValue *value1,
 161                                          const GValue *value2);
 162 };
 163 GType   g_param_type_register_static    (const gchar              *name,
 164                                          const GParamSpecTypeInfo *pspec_info);
 165
 166
 167 /* --- protected --- */
 168 gpointer        g_param_spec_internal           (GType          param_type,
 169                                                  const gchar   *name,
 170                                                  const gchar   *nick,
 171                                                  const gchar   *blurb,
 172                                                  GParamFlags    flags);
 173 GParamSpecPool* g_param_spec_pool_new           (gboolean       type_prefixing);
 174 void            g_param_spec_pool_insert        (GParamSpecPool *pool,
 175                                                  GParamSpec     *pspec,
 176                                                  GType           owner_type);
 177 void            g_param_spec_pool_remove        (GParamSpecPool *pool,
 178                                                  GParamSpec     *pspec);
 179 GParamSpec*     g_param_spec_pool_lookup        (GParamSpecPool *pool,
 180                                                  const gchar    *param_name,
 181                                                  GType           owner_type,
 182                                                  gboolean        walk_ancestors);
 183 GList*          g_param_spec_pool_list_owned    (GParamSpecPool *pool,
 184                                                  GType           owner_type);
 185 GParamSpec**    g_param_spec_pool_list          (GParamSpecPool *pool,
 186                                                  GType           owner_type,
 187                                                  guint          *n_pspecs_p);
 188
 189
 190
 191 /* contracts:
 192  *
 193  * gboolean value_validate (GParamSpec *pspec,
 194  *                          GValue     *value):
 195  *      modify value contents in the least destructive way, so
 196  *      that it complies with pspec's requirements (i.e.
 197  *      according to minimum/maximum ranges etc...). return
 198  *      whether modification was necessary.
 199  *
 200  * gint values_cmp (GParamSpec   *pspec,
 201  *                  const GValue *value1,
 202  *                  const GValue *value2):
 203  *      return value1 - value2, i.e. (-1) if value1 < value2,
 204  *      (+1) if value1 > value2, and (0) otherwise (equality)
 205  */
 206
 207 G_END_DECLS
 208
 209 #endif /* __G_PARAM_H__ */