gobject/genums.h

/* GObject - GLib Type, Object, Parameter and Signal Library
 * Copyright (C) 1998-1999, 2000-2001 Tim Janik and Red Hat, Inc.
 *
 * SPDX-License-Identifier: LGPL-2.1-or-later
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General
 * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
 */
#ifndef __G_ENUMS_H__
#define __G_ENUMS_H__

#if !defined (__GLIB_GOBJECT_H_INSIDE__) && !defined (GOBJECT_COMPILATION)
#error "Only <glib-object.h> can be included directly."
#endif

#include <gobject/gtype.h>

G_BEGIN_DECLS

/* --- type macros --- */
/**
 * G_TYPE_IS_ENUM:
 * @type: a #GType ID.
 * 
 * Checks whether @type "is a" %G_TYPE_ENUM.
 *
 * Returns: %TRUE if @type "is a" %G_TYPE_ENUM.
 */
#define G_TYPE_IS_ENUM(type)	       (G_TYPE_FUNDAMENTAL (type) == G_TYPE_ENUM)
/**
 * G_ENUM_CLASS:
 * @class: a valid #GEnumClass
 * 
 * Casts a derived #GEnumClass structure into a #GEnumClass structure.
 */
#define G_ENUM_CLASS(class)	       (G_TYPE_CHECK_CLASS_CAST ((class), G_TYPE_ENUM, GEnumClass))
/**
 * G_IS_ENUM_CLASS:
 * @class: a #GEnumClass
 * 
 * Checks whether @class "is a" valid #GEnumClass structure of type %G_TYPE_ENUM
 * or derived.
 */
#define G_IS_ENUM_CLASS(class)	       (G_TYPE_CHECK_CLASS_TYPE ((class), G_TYPE_ENUM))
/**
 * G_ENUM_CLASS_TYPE:
 * @class: a #GEnumClass
 * 
 * Get the type identifier from a given #GEnumClass structure.
 *
 * Returns: the #GType
 */
#define G_ENUM_CLASS_TYPE(class)       (G_TYPE_FROM_CLASS (class))
/**
 * G_ENUM_CLASS_TYPE_NAME:
 * @class: a #GEnumClass
 * 
 * Get the static type name from a given #GEnumClass structure.
 *
 * Returns: the type name.
 */
#define G_ENUM_CLASS_TYPE_NAME(class)  (g_type_name (G_ENUM_CLASS_TYPE (class)))


/**
 * G_TYPE_IS_FLAGS:
 * @type: a #GType ID.
 *
 * Checks whether @type "is a" %G_TYPE_FLAGS. 
 *
 * Returns: %TRUE if @type "is a" %G_TYPE_FLAGS.
 */
#define G_TYPE_IS_FLAGS(type)	       (G_TYPE_FUNDAMENTAL (type) == G_TYPE_FLAGS)
/**
 * G_FLAGS_CLASS:
 * @class: a valid #GFlagsClass
 * 
 * Casts a derived #GFlagsClass structure into a #GFlagsClass structure.
 */
#define G_FLAGS_CLASS(class)	       (G_TYPE_CHECK_CLASS_CAST ((class), G_TYPE_FLAGS, GFlagsClass))
/**
 * G_IS_FLAGS_CLASS:
 * @class: a #GFlagsClass
 * 
 * Checks whether @class "is a" valid #GFlagsClass structure of type %G_TYPE_FLAGS
 * or derived.
 */
#define G_IS_FLAGS_CLASS(class)        (G_TYPE_CHECK_CLASS_TYPE ((class), G_TYPE_FLAGS))
/**
 * G_FLAGS_CLASS_TYPE:
 * @class: a #GFlagsClass
 * 
 * Get the type identifier from a given #GFlagsClass structure.
 *
 * Returns: the #GType
 */
#define G_FLAGS_CLASS_TYPE(class)      (G_TYPE_FROM_CLASS (class))
/**
 * G_FLAGS_CLASS_TYPE_NAME:
 * @class: a #GFlagsClass
 * 
 * Get the static type name from a given #GFlagsClass structure.
 *
 * Returns: the type name.
 */
#define G_FLAGS_CLASS_TYPE_NAME(class) (g_type_name (G_FLAGS_CLASS_TYPE (class)))


/**
 * G_VALUE_HOLDS_ENUM:
 * @value: a valid #GValue structure
 * 
 * Checks whether the given #GValue can hold values derived from type %G_TYPE_ENUM.
 * 
 * Returns: %TRUE on success.
 */
#define G_VALUE_HOLDS_ENUM(value)      (G_TYPE_CHECK_VALUE_TYPE ((value), G_TYPE_ENUM))
/**
 * G_VALUE_HOLDS_FLAGS:
 * @value: a valid #GValue structure
 * 
 * Checks whether the given #GValue can hold values derived from type %G_TYPE_FLAGS.
 * 
 * Returns: %TRUE on success.
 */
#define G_VALUE_HOLDS_FLAGS(value)     (G_TYPE_CHECK_VALUE_TYPE ((value), G_TYPE_FLAGS))


/* --- enum/flag values & classes --- */
typedef struct _GEnumClass  GEnumClass;
typedef struct _GFlagsClass GFlagsClass;
typedef struct _GEnumValue  GEnumValue;
typedef struct _GFlagsValue GFlagsValue;

/**
 * GEnumClass:
 * @g_type_class: the parent class
 * @minimum: the smallest possible value.
 * @maximum: the largest possible value.
 * @n_values: the number of possible values.
 * @values: an array of #GEnumValue structs describing the 
 *  individual values.
 * 
 * The class of an enumeration type holds information about its 
 * possible values.
 */
struct	_GEnumClass
{
  GTypeClass  g_type_class;

  /*< public >*/  
  gint	      minimum;
  gint	      maximum;
  guint	      n_values;
  GEnumValue *values;
};
/**
 * GFlagsClass:
 * @g_type_class: the parent class
 * @mask: a mask covering all possible values.
 * @n_values: the number of possible values.
 * @values: an array of #GFlagsValue structs describing the 
 *  individual values.
 * 
 * The class of a flags type holds information about its 
 * possible values.
 */
struct	_GFlagsClass
{
  GTypeClass   g_type_class;
  
  /*< public >*/  
  guint	       mask;
  guint	       n_values;
  GFlagsValue *values;
};
/**
 * GEnumValue:
 * @value: the enum value
 * @value_name: the name of the value
 * @value_nick: the nickname of the value
 * 
 * A structure which contains a single enum value, its name, and its
 * nickname.
 */
struct _GEnumValue
{
  gint	 value;
  const gchar *value_name;
  const gchar *value_nick;
};
/**
 * GFlagsValue:
 * @value: the flags value
 * @value_name: the name of the value
 * @value_nick: the nickname of the value
 * 
 * A structure which contains a single flags value, its name, and its
 * nickname.
 */
struct _GFlagsValue
{
  guint	 value;
  const gchar *value_name;
  const gchar *value_nick;
};


/* --- prototypes --- */
GLIB_AVAILABLE_IN_ALL
GEnumValue*	g_enum_get_value		(GEnumClass	*enum_class,
						 gint		 value);
GLIB_AVAILABLE_IN_ALL
GEnumValue*	g_enum_get_value_by_name	(GEnumClass	*enum_class,
						 const gchar	*name);
GLIB_AVAILABLE_IN_ALL
GEnumValue*	g_enum_get_value_by_nick	(GEnumClass	*enum_class,
						 const gchar	*nick);
GLIB_AVAILABLE_IN_ALL
GFlagsValue*	g_flags_get_first_value		(GFlagsClass	*flags_class,
						 guint		 value);
GLIB_AVAILABLE_IN_ALL
GFlagsValue*	g_flags_get_value_by_name	(GFlagsClass	*flags_class,
						 const gchar	*name);
GLIB_AVAILABLE_IN_ALL
GFlagsValue*	g_flags_get_value_by_nick	(GFlagsClass	*flags_class,
						 const gchar	*nick);
GLIB_AVAILABLE_IN_2_54
gchar          *g_enum_to_string                (GType           g_enum_type,
                                                 gint            value);
GLIB_AVAILABLE_IN_2_54
gchar          *g_flags_to_string               (GType           flags_type,
                                                 guint           value);
GLIB_AVAILABLE_IN_ALL
void            g_value_set_enum        	(GValue         *value,
						 gint            v_enum);
GLIB_AVAILABLE_IN_ALL
gint            g_value_get_enum        	(const GValue   *value);
GLIB_AVAILABLE_IN_ALL
void            g_value_set_flags       	(GValue         *value,
						 guint           v_flags);
GLIB_AVAILABLE_IN_ALL
guint           g_value_get_flags       	(const GValue   *value);



/* --- registration functions --- */
/* const_static_values is a NULL terminated array of enum/flags
 * values that is taken over!
 */
GLIB_AVAILABLE_IN_ALL
GType	g_enum_register_static	   (const gchar	      *name,
				    const GEnumValue  *const_static_values);
GLIB_AVAILABLE_IN_ALL
GType	g_flags_register_static	   (const gchar	      *name,
				    const GFlagsValue *const_static_values);
/* functions to complete the type information
 * for enums/flags implemented by plugins
 */
GLIB_AVAILABLE_IN_ALL
void	g_enum_complete_type_info  (GType	       g_enum_type,
				    GTypeInfo	      *info,
				    const GEnumValue  *const_values);
GLIB_AVAILABLE_IN_ALL
void	g_flags_complete_type_info (GType	       g_flags_type,
				    GTypeInfo	      *info,
				    const GFlagsValue *const_values);

/* {{{ Macros */

/**
 * G_DEFINE_ENUM_VALUE:
 * @EnumValue: an enumeration value
 * @EnumNick: a short string representing the enumeration value
 *
 * Defines an enumeration value, and maps it to a "nickname".
 *
 * This macro can only be used with G_DEFINE_ENUM_TYPE() and
 * G_DEFINE_FLAGS_TYPE().
 *
 * Since: 2.74
 */
#define G_DEFINE_ENUM_VALUE(EnumValue, EnumNick) \
  { EnumValue, #EnumValue, EnumNick } \
  GLIB_AVAILABLE_MACRO_IN_2_74

/**
 * G_DEFINE_ENUM_TYPE:
 * @TypeName: the enumeration type, in `CamelCase`
 * @type_name: the enumeration type prefixed, in `snake_case`
 * @...: a list of enumeration values, defined using G_DEFINE_ENUM_VALUE()
 *
 * A convenience macro for defining enumeration types.
 *
 * This macro will generate a `*_get_type()` function for the
 * given @TypeName, using @type_name as the function prefix.
 *
 * |[<!-- language="C" -->
 * G_DEFINE_ENUM_TYPE (GtkOrientation, gtk_orientation,
 *   G_DEFINE_ENUM_VALUE (GTK_ORIENTATION_HORIZONTAL, "horizontal"),
 *   G_DEFINE_ENUM_VALUE (GTK_ORIENTATION_VERTICAL, "vertical"))
 * ]|
 *
 * For projects that have multiple enumeration types, or enumeration
 * types with many values, you should consider using glib-mkenums to
 * generate the type function.
 *
 * Since: 2.74
 */
#define G_DEFINE_ENUM_TYPE(TypeName, type_name, ...) \
GType \
type_name ## _get_type (void) { \
  static gsize g_define_type__static = 0; \
  if (g_once_init_enter (&g_define_type__static)) { \
    static const GEnumValue enum_values[] = { \
      __VA_ARGS__ , \
      { 0, NULL, NULL }, \
    }; \
    GType g_define_type = g_enum_register_static (g_intern_static_string (#TypeName), enum_values); \
    g_once_init_leave (&g_define_type__static, g_define_type); \
  } \
  return g_define_type__static; \
} \
  GLIB_AVAILABLE_MACRO_IN_2_74

/**
 * G_DEFINE_FLAGS_TYPE:
 * @TypeName: the enumeration type, in `CamelCase`
 * @type_name: the enumeration type prefixed, in `snake_case`
 * @...: a list of enumeration values, defined using G_DEFINE_ENUM_VALUE()
 *
 * A convenience macro for defining flag types.
 *
 * This macro will generate a `*_get_type()` function for the
 * given @TypeName, using @type_name as the function prefix.
 *
 * |[<!-- language="C" -->
 * G_DEFINE_FLAGS_TYPE (GSettingsBindFlags, g_settings_bind_flags,
 *   G_DEFINE_ENUM_VALUE (G_SETTINGS_BIND_DEFAULT, "default"),
 *   G_DEFINE_ENUM_VALUE (G_SETTINGS_BIND_GET, "get"),
 *   G_DEFINE_ENUM_VALUE (G_SETTINGS_BIND_SET, "set"),
 *   G_DEFINE_ENUM_VALUE (G_SETTINGS_BIND_NO_SENSITIVITY, "no-sensitivity"),
 *   G_DEFINE_ENUM_VALUE (G_SETTINGS_BIND_GET_NO_CHANGES, "get-no-changes"),
 *   G_DEFINE_ENUM_VALUE (G_SETTINGS_BIND_INVERT_BOOLEAN, "invert-boolean"))
 * ]|
 *
 * For projects that have multiple enumeration types, or enumeration
 * types with many values, you should consider using glib-mkenums to
 * generate the type function.
 *
 * Since: 2.74
 */
#define G_DEFINE_FLAGS_TYPE(TypeName, type_name, ...) \
GType \
type_name ## _get_type (void) { \
  static gsize g_define_type__static = 0; \
  if (g_once_init_enter (&g_define_type__static)) { \
    static const GFlagsValue flags_values[] = { \
      __VA_ARGS__ , \
      { 0, NULL, NULL }, \
    }; \
    GType g_define_type = g_flags_register_static (g_intern_static_string (#TypeName), flags_values); \
    g_once_init_leave (&g_define_type__static, g_define_type); \
  } \
  return g_define_type__static; \
} \
  GLIB_AVAILABLE_MACRO_IN_2_74

G_END_DECLS

#endif /* __G_ENUMS_H__ */