* 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, write to the
- * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
- * Boston, MA 02111-1307, USA.
+ * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
/*
#include "gvalue.h"
#include "gvaluecollector.h"
#include "gbsearcharray.h"
-#include "gobjectalias.h"
+#include "gtype-private.h"
/**
* other type
* @see_also: The fundamental types which all support #GValue
* operations and thus can be used as a type initializer for
- * g_value_init() are defined by a separate interface. See the <link
- * linkend="gobject-Standard-Parameter-and-Value-Types">Standard
- * Values API</link> for details.
+ * g_value_init() are defined by a separate interface. See the
+ * [standard values API][gobject-Standard-Parameter-and-Value-Types]
+ * for details
* @title: Generic values
*
* The #GValue structure is basically a variable container that consists
* The code in the example program below demonstrates #GValue's
* features.
*
- * |[
- * #include <glib-object.h>
+ * |[<!-- language="C" -->
+ * #include <glib-object.h>
*
* static void
* int2string (const GValue *src_value,
* main (int argc,
* char *argv[])
* {
- * /* GValues must start zero-filled */
- * GValue a = {0};
- * GValue b = {0};
+ * // GValues must be initialized
+ * GValue a = G_VALUE_INIT;
+ * GValue b = G_VALUE_INIT;
* const gchar *message;
*
- * g_type_init ();
+ * // The GValue starts empty
+ * g_assert (!G_VALUE_HOLDS_STRING (&a));
*
- * /* The GValue starts empty */
- * g_assert (!G_VALUE_HOLDS_STRING (&a));
+ * // Put a string in it
+ * g_value_init (&a, G_TYPE_STRING);
+ * g_assert (G_VALUE_HOLDS_STRING (&a));
+ * g_value_set_static_string (&a, "Hello, world!");
+ * g_printf ("%s\n", g_value_get_string (&a));
*
- * /* Put a string in it */
- * g_value_init (&a, G_TYPE_STRING);
- * g_assert (G_VALUE_HOLDS_STRING (&a));
- * g_value_set_static_string (&a, "Hello, world!");
- * g_printf ("%s\n", g_value_get_string (&a));
+ * // Reset it to its pristine state
+ * g_value_unset (&a);
*
- * /* Reset it to its pristine state */
- * g_value_unset (&a);
+ * // It can then be reused for another type
+ * g_value_init (&a, G_TYPE_INT);
+ * g_value_set_int (&a, 42);
*
- * /* It can then be reused for another type */
- * g_value_init (&a, G_TYPE_INT);
- * g_value_set_int (&a, 42);
+ * // Attempt to transform it into a GValue of type STRING
+ * g_value_init (&b, G_TYPE_STRING);
*
- * /* Attempt to transform it into a GValue of type STRING */
- * g_value_init (&b, G_TYPE_STRING);
- *
- * /* An INT is transformable to a STRING */
+ * // An INT is transformable to a STRING
* g_assert (g_value_type_transformable (G_TYPE_INT, G_TYPE_STRING));
*
- * g_value_transform (&a, &b);
- * g_printf ("%s\n", g_value_get_string (&b));
+ * g_value_transform (&a, &b);
+ * g_printf ("%s\n", g_value_get_string (&b));
*
- * /* Attempt to transform it again using a custom transform function */
+ * // Attempt to transform it again using a custom transform function
* g_value_register_transform_func (G_TYPE_INT, G_TYPE_STRING, int2string);
- * g_value_transform (&a, &b);
- * g_printf ("%s\n", g_value_get_string (&b));
+ * g_value_transform (&a, &b);
+ * g_printf ("%s\n", g_value_get_string (&b));
* return 0;
* }
* ]|
static GBSearchConfig transform_bconfig = {
sizeof (TransformEntry),
transform_entries_cmp,
- 0,
+ G_BSEARCH_ARRAY_ALIGN_POWER2,
};
/* --- functions --- */
void
-g_value_c_init (void)
+_g_value_c_init (void)
{
transform_array = g_bsearch_array_create (&transform_bconfig);
}
*
* Initializes @value with the default value of @type.
*
- * Returns: the #GValue structure that has been passed in
+ * Returns: (transfer none): the #GValue structure that has been passed in
*/
GValue*
g_value_init (GValue *value,
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_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_warning ("%s: cannot initialize GValue with type '%s', %s",
G_STRLOC,
g_type_name (g_type),
g_type_value_table_peek (g_type) ?
/**
* g_value_peek_pointer:
- * @value: An initialized #GValue structure.
+ * @value: An initialized #GValue structure
*
- * Return the value contents as pointer. This function asserts that
+ * Returns the value contents as pointer. This function asserts that
* g_value_fits_pointer() returned %TRUE for the passed in value.
* This is an internal function introduced mainly for C marshallers.
*
- * Returns: %TRUE if @value will fit inside a pointer value.
+ * Returns: (transfer none): the value contents as pointer
*/
gpointer
g_value_peek_pointer (const GValue *value)
/**
* g_value_set_instance:
* @value: An initialized #GValue structure.
- * @instance: the instance
+ * @instance: (allow-none): the instance
*
* Sets @value from an instantiatable type via the
* value_table's collect_value() function.
}
}
+/**
+ * g_value_init_from_instance:
+ * @value: An uninitialized #GValue structure.
+ * @instance: the instance
+ *
+ * Initializes and sets @value from an instantiatable type via the
+ * value_table's collect_value() function.
+ *
+ * Note: The @value will be initialised with the exact type of
+ * @instance. If you wish to set the @value's type to a different GType
+ * (such as a parent class GType), you need to manually call
+ * g_value_init() and g_value_set_instance().
+ *
+ * Since: 2.42
+ */
+void
+g_value_init_from_instance (GValue *value,
+ gpointer instance)
+{
+ g_return_if_fail (value != NULL && G_VALUE_TYPE(value) == 0);
+
+ if (G_IS_OBJECT (instance))
+ {
+ /* Fast-path.
+ * If G_IS_OBJECT() succeeds we know:
+ * * that instance is present and valid
+ * * that it is a GObject, and therefore we can directly
+ * use the collect implementation (g_object_ref) */
+ value_meminit (value, G_TYPE_FROM_INSTANCE (instance));
+ value->data[0].v_pointer = g_object_ref (instance);
+ }
+ else
+ {
+ GType g_type;
+ GTypeValueTable *value_table;
+ GTypeCValue cvalue;
+ gchar *error_msg;
+
+ g_return_if_fail (G_TYPE_CHECK_INSTANCE (instance));
+
+ g_type = G_TYPE_FROM_INSTANCE (instance);
+ value_table = g_type_value_table_peek (g_type);
+ g_return_if_fail (strcmp (value_table->collect_format, "p") == 0);
+
+ memset (&cvalue, 0, sizeof (cvalue));
+ cvalue.v_pointer = instance;
+
+ /* setup and collect */
+ value_meminit (value, g_type);
+ value_table->value_init (value);
+ error_msg = value_table->collect_value (value, 1, &cvalue, 0);
+ if (error_msg)
+ {
+ g_warning ("%s: %s", G_STRLOC, error_msg);
+ g_free (error_msg);
+
+ /* we purposely leak the value here, it might not be
+ * in a sane state if an error condition occoured
+ */
+ value_meminit (value, g_type);
+ value_table->value_init (value);
+ }
+ }
+}
+
static GValueTransform
transform_func_lookup (GType src_type,
GType dest_type)
}
/**
- * g_value_register_transform_func:
+ * g_value_register_transform_func: (skip)
* @src_type: Source type.
* @dest_type: Target type.
* @transform_func: a function which transforms values of type @src_type
#if 0 /* let transform function replacement be a valid operation */
if (g_bsearch_array_lookup (transform_array, &transform_bconfig, &entry))
- g_warning ("reregistering value transformation function (%p) for `%s' to `%s'",
+ g_warning ("reregistering value transformation function (%p) for '%s' to '%s'",
transform_func,
g_type_name (src_type),
g_type_name (dest_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.
+ * of type @src_type into values of type @dest_type. Note that for
+ * the types to be transformable, they must be compatible and a
+ * transform function must be registered.
*
* Returns: %TRUE if the transformation is possible, %FALSE otherwise.
*/
}
return FALSE;
}
-
-#define __G_VALUE_C__
-#include "gobjectaliasdef.c"
projects / platform / upstream / glib.git / blobdiff