G_TYPE_IS_PARAM()

#define G_TYPE_IS_PARAM(type)		(G_TYPE_FUNDAMENTAL (type) == G_TYPE_PARAM)

Returns whether type "is a" G_TYPE_PARAM.

G_PARAM_SPEC()

#define G_PARAM_SPEC(pspec)		(G_TYPE_CHECK_INSTANCE_CAST ((pspec), G_TYPE_PARAM, GParamSpec))

Cast a derived GParamSpec object (e.g. of type GParamSpecInt) into a GParamSpec object.

G_IS_PARAM_SPEC()

#define G_IS_PARAM_SPEC(pspec)		(G_TYPE_CHECK_INSTANCE_TYPE ((pspec), G_TYPE_PARAM))

Check whether pspec "is a" valid GParamSpec structure of type G_TYPE_PARAM or derived.

G_PARAM_SPEC_CLASS()

#define G_PARAM_SPEC_CLASS(pclass)      (G_TYPE_CHECK_CLASS_CAST ((pclass), G_TYPE_PARAM, GParamSpecClass))

Cast a derived GParamSpecClass structure into a GParamSpecClass structure.

G_IS_PARAM_SPEC_CLASS()

#define G_IS_PARAM_SPEC_CLASS(pclass)   (G_TYPE_CHECK_CLASS_TYPE ((pclass), G_TYPE_PARAM))

Check whether pclass "is a" valid GParamSpecClass structure of type G_TYPE_PARAM or derived.

G_PARAM_SPEC_GET_CLASS()

#define G_PARAM_SPEC_GET_CLASS(pspec)	(G_TYPE_INSTANCE_GET_CLASS ((pspec), G_TYPE_PARAM, GParamSpecClass))

Retrieve the GParamSpecClass of a GParamSpec.

G_PARAM_SPEC_TYPE()

#define G_PARAM_SPEC_TYPE(pspec)	(G_TYPE_FROM_INSTANCE (pspec))

Retrieve the GType of this pspec.

G_PARAM_SPEC_TYPE_NAME()

#define G_PARAM_SPEC_TYPE_NAME(pspec)	(g_type_name (G_PARAM_SPEC_TYPE (pspec)))

Retrieve the GType name of this pspec.

G_PARAM_SPEC_VALUE_TYPE()

#define	G_PARAM_SPEC_VALUE_TYPE(pspec)	(G_PARAM_SPEC (pspec)->value_type)

Retrieve the GType to intiialize a GValue for this parameter.

struct GParamSpec

struct GParamSpec {

  GTypeInstance  g_type_instance;

  gchar         *name;
  GParamFlags    flags;
  GType		 value_type;
  GType		 owner_type;	/* class using this property */

};

struct GParamSpecClass

struct GParamSpecClass {

  GTypeClass      g_type_class;

  GType		  value_type;

  void	        (*finalize)		(GParamSpec   *pspec);

  /* GParam methods */
  void          (*value_set_default)    (GParamSpec   *pspec,
					 GValue       *value);
  gboolean      (*value_validate)       (GParamSpec   *pspec,
					 GValue       *value);
  gint          (*values_cmp)           (GParamSpec   *pspec,
					 const GValue *value1,
					 const GValue *value2);
  gpointer	  dummy[4];
};

enum GParamFlags

typedef enum
{
  G_PARAM_READABLE            = 1 << 0,
  G_PARAM_WRITABLE            = 1 << 1,
  G_PARAM_CONSTRUCT	      = 1 << 2,
  G_PARAM_CONSTRUCT_ONLY      = 1 << 3,
  G_PARAM_LAX_VALIDATION      = 1 << 4,
  G_PARAM_PRIVATE	      = 1 << 5
} GParamFlags;

Through the GParamFlags flag values, certain aspects of parameters can be configured.

G_PARAM_READWRITE

#define	G_PARAM_READWRITE	(G_PARAM_READABLE | G_PARAM_WRITABLE)

GParamFlags value alias for G_PARAM_READABLE | G_PARAM_WRITABLE.

G_PARAM_MASK

#define	G_PARAM_MASK		(0x000000ff)

Mask containing the bits of GParamSpec.flags which are reserved for GLib.

G_PARAM_USER_SHIFT

#define	G_PARAM_USER_SHIFT	(8)

Minimum shift count to be used for user defined flags, to be stored in GParamSpec.flags.

g_param_spec_ref ()

GParamSpec* g_param_spec_ref                (GParamSpec *pspec);

Increment the reference count of pspec.

g_param_spec_unref ()

void        g_param_spec_unref              (GParamSpec *pspec);

Decrement the reference count of a pspec.

g_param_spec_sink ()

void        g_param_spec_sink               (GParamSpec *pspec);

The initial reference count of a newly created GParamSpec is 1, eventhough no one has explicitely called g_param_spec_ref() on it yet. So the einital reference count is flagged as "floating", untill someone calls: g_param_spec_ref (pspec); g_param_spec_sink (pspec); in sequence on it, taking over the initial reference count (thus ending up with a pspec that has a reference count of 1 still, but is not flagged "floating" anymore).

g_param_value_set_default ()

void        g_param_value_set_default       (GParamSpec *pspec,
                                             GValue *value);

Set value to its default value as specified in pspec.

g_param_value_defaults ()

gboolean    g_param_value_defaults          (GParamSpec *pspec,
                                             GValue *value);

Check whether value contains the default value as specified in pspec.

g_param_value_validate ()

gboolean    g_param_value_validate          (GParamSpec *pspec,
                                             GValue *value);

Ensure that the contents of value comply with the specifications set out by pspec. For example, a GParamSpecInt might require that integers stored in value may not be smaller than -42 and not be greater than +42. If value contains an integer outside of this range, it is modified accordingly, so the resulting value will fit into the range -42 .. +42.

g_param_value_convert ()

gboolean    g_param_value_convert           (GParamSpec *pspec,
                                             const GValue *src_value,
                                             GValue *dest_value,
                                             gboolean strict_validation);

This function transforms src_value into dest_value if possible, and then validates dest_value, in order for it to conform to pspec. If strict_validation is TRUE this function will only suceed if the transformed dest_value complied to pspec without modifications. See also g_value_type_transformable(), g_value_transform() and g_param_value_validate().

g_param_values_cmp ()

gint        g_param_values_cmp              (GParamSpec *pspec,
                                             const GValue *value1,
                                             const GValue *value2);

Compare value1 with value2 according to pspec, and return -1, 0 or +1, if value1 is found to be less than, equal to or greater than value2, respectively.

g_param_spec_get_name ()

G_CONST_RETURN gchar* g_param_spec_get_name (GParamSpec *pspec);

g_param_spec_get_nick ()

G_CONST_RETURN gchar* g_param_spec_get_nick (GParamSpec *pspec);

g_param_spec_get_blurb ()

G_CONST_RETURN gchar* g_param_spec_get_blurb
                                            (GParamSpec *pspec);

g_param_spec_get_qdata ()

gpointer    g_param_spec_get_qdata          (GParamSpec *pspec,
                                             GQuark quark);

g_param_spec_set_qdata ()

void        g_param_spec_set_qdata          (GParamSpec *pspec,
                                             GQuark quark,
                                             gpointer data);

g_param_spec_set_qdata_full ()

void        g_param_spec_set_qdata_full     (GParamSpec *pspec,
                                             GQuark quark,
                                             gpointer data,
                                             GDestroyNotify destroy);

g_param_spec_steal_qdata ()

gpointer    g_param_spec_steal_qdata        (GParamSpec *pspec,
                                             GQuark quark);

g_param_spec_internal ()

gpointer    g_param_spec_internal           (GType param_type,
                                             const gchar *name,
                                             const gchar *nick,
                                             const gchar *blurb,
                                             GParamFlags flags);

Creates a new GParamSpec instance.

A property name consists of segments consisting of ASCII letters and digits, separated by either the '-' or '_' character. The first character of a property name must be a letter. Names which violate these rules lead to undefined behaviour.

When creating and looking up a GParamSpec, either separator can be used, but they cannot be mixed. Using '-' is considerably more efficient and in fact required when using property names as detail strings for signals.

struct GParamSpecTypeInfo

struct GParamSpecTypeInfo {

  /* type system portion */
  guint16         instance_size;                               /* obligatory */
  guint16         n_preallocs;                                 /* optional */
  void		(*instance_init)	(GParamSpec   *pspec); /* optional */

  /* class portion */
  GType           value_type;				       /* obligatory */
  void          (*finalize)             (GParamSpec   *pspec); /* optional */
  void          (*value_set_default)    (GParamSpec   *pspec,  /* recommended */
					 GValue       *value);
  gboolean      (*value_validate)       (GParamSpec   *pspec,  /* optional */
					 GValue       *value);
  gint          (*values_cmp)           (GParamSpec   *pspec,  /* recommended */
					 const GValue *value1,
					 const GValue *value2);
};

g_param_type_register_static ()

GType       g_param_type_register_static    (const gchar *name,
                                             const GParamSpecTypeInfo *pspec_info);

struct GParamSpecPool

struct GParamSpecPool;

g_param_spec_pool_new ()

GParamSpecPool* g_param_spec_pool_new       (gboolean type_prefixing);

g_param_spec_pool_insert ()

void        g_param_spec_pool_insert        (GParamSpecPool *pool,
                                             GParamSpec *pspec,
                                             GType owner_type);

g_param_spec_pool_remove ()

void        g_param_spec_pool_remove        (GParamSpecPool *pool,
                                             GParamSpec *pspec);

g_param_spec_pool_lookup ()

GParamSpec* g_param_spec_pool_lookup        (GParamSpecPool *pool,
                                             const gchar *param_name,
                                             GType owner_type,
                                             gboolean walk_ancestors);

g_param_spec_pool_list ()

GParamSpec** g_param_spec_pool_list         (GParamSpecPool *pool,
                                             GType owner_type,
                                             guint *n_pspecs_p);

g_param_spec_pool_list_owned ()

GList*      g_param_spec_pool_list_owned    (GParamSpecPool *pool,
                                             GType owner_type);