/**
* g_value_type_compatible:
* @src_type: source type to be copied.
* @dest_type: destination type for copying.
*
* Returns whether a #GValue of type @src_type can be copied into
* a #GValue of type @dest_type.
*
* Returns: %TRUE if g_value_copy() is possible with @src_type and @dest_type.
*/
gboolean
g_value_type_compatible (GType src_type,
GType dest_type)
{
g_return_val_if_fail (G_TYPE_IS_VALUE (src_type), FALSE);
g_return_val_if_fail (G_TYPE_IS_VALUE (dest_type), FALSE);
return (g_type_is_a (src_type, dest_type) &&
g_type_value_table_peek (dest_type) == g_type_value_table_peek (src_type));
}
/**
* g_value_type_transformable:
* @src_type: Source type.
* @dest_type: Target type.
*
* Check whether g_value_transform() is able to transform values
* of type @src_type into values of type @dest_type.
*
* Returns: %TRUE if the transformation is possible, %FALSE otherwise.
*/
gboolean
g_value_type_transformable (GType src_type,
GType dest_type)
{
g_return_val_if_fail (G_TYPE_IS_VALUE (src_type), FALSE);
g_return_val_if_fail (G_TYPE_IS_VALUE (dest_type), FALSE);
return (g_value_type_compatible (src_type, dest_type) ||
transform_func_lookup (src_type, dest_type) != NULL);
}
/**
* g_value_init:
* @value: A zero-filled (uninitialized) #GValue structure.
* @g_type: Type the #GValue should hold values of.
*
* Initializes @value with the default value of @type.
*
* Returns: (transfer none): the #GValue structure that has been passed in
*/
GValue*
g_value_init (GValue *value,
GType g_type)
{
/* g_return_val_if_fail (G_TYPE_IS_VALUE (g_type), NULL); be more elaborate below */
g_return_val_if_fail (value != NULL, NULL);
/* g_return_val_if_fail (G_VALUE_TYPE (value) == 0, NULL); be more elaborate below */
if (G_TYPE_IS_VALUE (g_type) && G_VALUE_TYPE (value) == 0)
{
GTypeValueTable *value_table = g_type_value_table_peek (g_type);
/* setup and init */
value_meminit (value, g_type);
value_table->value_init (value);
}
else if (G_VALUE_TYPE (value))
g_warning ("%s: cannot initialize GValue with type '%s', the value has already been initialized as '%s'",
G_STRLOC,
g_type_name (g_type),
g_type_name (G_VALUE_TYPE (value)));
else /* !G_TYPE_IS_VALUE (g_type) */
g_warning ("%s: cannot initialize GValue with type '%s', %s",
G_STRLOC,
g_type_name (g_type),
g_type_value_table_peek (g_type) ?
"this type is abstract with regards to GValue use, use a more specific (derived) type" :
"this type has no GTypeValueTable implementation");
return value;
}
/**
* g_value_dup_boxed:
* @value: a valid #GValue of %G_TYPE_BOXED derived type
*
* Get the contents of a %G_TYPE_BOXED derived #GValue. Upon getting,
* the boxed value is duplicated and needs to be later freed with
* g_boxed_free(), e.g. like: g_boxed_free (G_VALUE_TYPE (@value),
* return_value);
*
* Returns: boxed contents of @value
*/
gpointer
g_value_dup_boxed (const GValue *value)
{
g_return_val_if_fail (G_VALUE_HOLDS_BOXED (value), NULL);
g_return_val_if_fail (G_TYPE_IS_VALUE (G_VALUE_TYPE (value)), NULL);
return value->data[0].v_pointer ? g_boxed_copy (G_VALUE_TYPE (value), value->data[0].v_pointer) : NULL;
}
/**
* g_value_get_boxed:
* @value: a valid #GValue of %G_TYPE_BOXED derived type
*
* Get the contents of a %G_TYPE_BOXED derived #GValue.
*
* Returns: boxed contents of @value
*/
gpointer
g_value_get_boxed (const GValue *value)
{
g_return_val_if_fail (G_VALUE_HOLDS_BOXED (value), NULL);
g_return_val_if_fail (G_TYPE_IS_VALUE (G_VALUE_TYPE (value)), NULL);
return value->data[0].v_pointer;
}
/**
* g_value_take_boxed:
* @value: a valid #GValue of %G_TYPE_BOXED derived type
* @v_boxed: duplicated unowned boxed value to be set
*
* Sets the contents of a %G_TYPE_BOXED derived #GValue to @v_boxed
* and takes over the ownership of the callers reference to @v_boxed;
* the caller doesn't have to unref it any more.
*
* Since: 2.4
*/
void
g_value_take_boxed (GValue *value,
gconstpointer boxed)
{
g_return_if_fail (G_VALUE_HOLDS_BOXED (value));
g_return_if_fail (G_TYPE_IS_VALUE (G_VALUE_TYPE (value)));
value_set_boxed_internal (value, boxed, FALSE, TRUE);
}
