Commit 3be3ad61 authored by Emmanuele Bassi's avatar Emmanuele Bassi

binding: Add a closure-based variant of bind_property_full()

Since using the function pointer version muddles the memory management
requirements of language bindings, we should implement a GClosure-based
variant on top of g_object_bind_property_full().

https://bugzilla.gnome.org/show_bug.cgi?id=622278
parent ca3b7b75
......@@ -867,6 +867,7 @@ g_binding_get_flags
g_object_bind_property
GBindingTransformFunc
g_object_bind_property_full
g_object_bind_property_with_closures
<SUBSECTION Standard>
G_TYPE_BINDING
G_TYPE_BINDING_FLAGS
......
......@@ -809,12 +809,6 @@ g_object_bind_property_full (gpointer source,
return NULL;
}
if (transform_to == NULL)
transform_to = default_transform_to;
if (transform_from == NULL)
transform_from = default_transform_from;
pspec = g_object_class_find_property (G_OBJECT_GET_CLASS (source), source_property);
if (pspec == NULL)
{
......@@ -881,9 +875,12 @@ g_object_bind_property_full (gpointer source,
"flags", flags,
NULL);
/* making these properties would be awkward, though not impossible */
binding->transform_s2t = transform_to;
binding->transform_t2s = transform_from;
if (transform_to != NULL)
binding->transform_s2t = transform_to;
if (transform_from != NULL)
binding->transform_t2s = transform_from;
binding->transform_data = user_data;
binding->notify = notify;
......@@ -951,3 +948,171 @@ g_object_bind_property (gpointer source,
NULL,
NULL, NULL);
}
typedef struct _TransformData
{
GClosure *transform_to_closure;
GClosure *transform_from_closure;
} TransformData;
static gboolean
bind_with_closures_transform_to (GBinding *binding,
const GValue *source,
GValue *target,
gpointer data)
{
TransformData *t_data = data;
GValue params[3] = { { 0, }, { 0, }, { 0, } };
GValue retval = { 0, };
gboolean res;
g_value_init (&params[0], G_TYPE_BINDING);
g_value_set_object (&params[0], binding);
g_value_init (&params[1], G_TYPE_VALUE);
g_value_set_boxed (&params[1], source);
g_value_init (&params[2], G_TYPE_VALUE);
g_value_set_boxed (&params[2], target);
g_value_init (&retval, G_TYPE_BOOLEAN);
g_value_set_boolean (&retval, FALSE);
g_closure_invoke (t_data->transform_to_closure, &retval, 3, params, NULL);
res = g_value_get_boolean (&retval);
if (res)
{
const GValue *out_value = g_value_get_boxed (&params[2]);
g_assert (out_value != NULL);
g_value_copy (out_value, target);
}
g_value_unset (&params[0]);
g_value_unset (&params[1]);
g_value_unset (&params[2]);
g_value_unset (&retval);
return res;
}
static gboolean
bind_with_closures_transform_from (GBinding *binding,
const GValue *source,
GValue *target,
gpointer data)
{
TransformData *t_data = data;
GValue params[3] = { { 0, }, { 0, }, { 0, } };
GValue retval = { 0, };
gboolean res;
g_value_init (&params[0], G_TYPE_BINDING);
g_value_set_object (&params[0], binding);
g_value_init (&params[1], G_TYPE_VALUE);
g_value_set_boxed (&params[1], source);
g_value_init (&params[2], G_TYPE_VALUE);
g_value_set_boxed (&params[2], target);
g_value_init (&retval, G_TYPE_BOOLEAN);
g_value_set_boolean (&retval, FALSE);
g_closure_invoke (t_data->transform_from_closure, &retval, 3, params, NULL);
res = g_value_get_boolean (&retval);
if (res)
{
const GValue *out_value = g_value_get_boxed (&params[2]);
g_assert (out_value != NULL);
g_value_copy (out_value, target);
}
g_value_unset (&params[0]);
g_value_unset (&params[1]);
g_value_unset (&params[2]);
g_value_unset (&retval);
return res;
}
static void
bind_with_closures_free_func (gpointer data)
{
TransformData *t_data = data;
if (t_data->transform_to_closure != NULL)
g_closure_unref (t_data->transform_to_closure);
if (t_data->transform_from_closure != NULL)
g_closure_unref (t_data->transform_from_closure);
g_slice_free (TransformData, t_data);
}
/**
* g_object_bind_property_with_closures:
* @source: the source #GObject
* @source_property: the property on @source to bind
* @target: the target #GObject
* @target_property: the property on @target to bind
* @flags: flags to pass to #GBinding
* @transform_to: a #GClosure wrapping the transformation function
* from the @source to the @target, or %NULL to use the default
* @transform_from: a #GClosure wrapping the transformation function
* from the @target to the @source, or %NULL to use the default
*
* Creates a binding between @source_property on @source and @target_property
* on @target, allowing you to set the transformation functions to be used by
* the binding.
*
* This function is the language bindings friendly version of
* g_object_bind_property_full(), using #GClosure<!-- -->s instead of
* function pointers.
*
* Rename to: g_object_bind_property_full
*
* Return value: (transfer none): the #GBinding instance representing the
* binding between the two #GObject instances. The binding is released
* whenever the #GBinding reference count reaches zero.
*
* Since: 2.26
*/
GBinding *
g_object_bind_property_with_closures (gpointer source,
const gchar *source_property,
gpointer target,
const gchar *target_property,
GBindingFlags flags,
GClosure *transform_to,
GClosure *transform_from)
{
TransformData *data;
data = g_slice_new0 (TransformData);
if (transform_to != NULL)
{
data->transform_to_closure = g_closure_ref (transform_to);
g_closure_sink (data->transform_to_closure);
}
if (transform_from != NULL)
{
data->transform_from_closure = g_closure_ref (transform_from);
g_closure_sink (data->transform_from_closure);
}
return g_object_bind_property_full (source, source_property,
target, target_property,
flags,
transform_to != NULL ? bind_with_closures_transform_to : NULL,
transform_from != NULL ? bind_with_closures_transform_from : NULL,
data,
bind_with_closures_free_func);
}
......@@ -103,20 +103,27 @@ GObject * g_binding_get_target (GBinding *binding);
G_CONST_RETURN gchar *g_binding_get_source_property (GBinding *binding);
G_CONST_RETURN gchar *g_binding_get_target_property (GBinding *binding);
GBinding *g_object_bind_property (gpointer source,
const gchar *source_property,
gpointer target,
const gchar *target_property,
GBindingFlags flags);
GBinding *g_object_bind_property_full (gpointer source,
const gchar *source_property,
gpointer target,
const gchar *target_property,
GBindingFlags flags,
GBindingTransformFunc transform_to,
GBindingTransformFunc transform_from,
gpointer user_data,
GDestroyNotify notify);
GBinding *g_object_bind_property (gpointer source,
const gchar *source_property,
gpointer target,
const gchar *target_property,
GBindingFlags flags);
GBinding *g_object_bind_property_full (gpointer source,
const gchar *source_property,
gpointer target,
const gchar *target_property,
GBindingFlags flags,
GBindingTransformFunc transform_to,
GBindingTransformFunc transform_from,
gpointer user_data,
GDestroyNotify notify);
GBinding *g_object_bind_property_with_closures (gpointer source,
const gchar *source_property,
gpointer target,
const gchar *target_property,
GBindingFlags flags,
GClosure *transform_to,
GClosure *transform_from);
G_END_DECLS
......
......@@ -21,6 +21,7 @@ g_binding_get_source_property
g_binding_get_target_property
g_object_bind_property
g_object_bind_property_full
g_object_bind_property_with_closures
#endif
#endif
......
......@@ -247,8 +247,8 @@ binding_default (void)
target, "bar",
G_BINDING_DEFAULT);
g_assert (g_binding_get_source (binding) == G_OBJECT (source));
g_assert (g_binding_get_target (binding) == G_OBJECT (target));
g_assert ((BindingSource *) g_binding_get_source (binding) == source);
g_assert ((BindingTarget *) g_binding_get_target (binding) == target);
g_assert_cmpstr (g_binding_get_source_property (binding), ==, "foo");
g_assert_cmpstr (g_binding_get_target_property (binding), ==, "bar");
g_assert_cmpint (g_binding_get_flags (binding), ==, G_BINDING_DEFAULT);
......@@ -329,6 +329,77 @@ binding_transform (void)
g_assert (unused_data);
}
static void
binding_transform_marshal (GClosure *closure,
GValue *return_value,
guint n_param_values,
const GValue *param_values,
gpointer invocation_hint G_GNUC_UNUSED,
gpointer marshal_data)
{
typedef gboolean (* GMarshalFunc_BOOLEAN__VALUE_VALUE) (gpointer data1,
gpointer arg_2,
gpointer arg_3,
gpointer data2);
register GMarshalFunc_BOOLEAN__VALUE_VALUE callback;
register GCClosure *cc = (GCClosure *) closure;
register gpointer data1, data2;
gboolean v_return;
if (G_CCLOSURE_SWAP_DATA (closure))
{
data1 = closure->data;
data2 = g_value_peek_pointer (param_values + 0);
}
else
{
data1 = g_value_peek_pointer (param_values + 0);
data2 = closure->data;
}
callback = (GMarshalFunc_BOOLEAN__VALUE_VALUE) (marshal_data ? marshal_data : cc->callback);
v_return = callback (data1,
g_value_get_boxed (param_values + 1),
g_value_get_boxed (param_values + 2),
data2);
g_value_set_boolean (return_value, v_return);
}
static void
binding_transform_closure (void)
{
BindingSource *source = g_object_new (binding_source_get_type (), NULL);
BindingTarget *target = g_object_new (binding_target_get_type (), NULL);
GBinding *binding;
gboolean unused_data_1 = FALSE, unused_data_2 = FALSE;
GClosure *c2f_clos, *f2c_clos;
c2f_clos = g_cclosure_new (G_CALLBACK (celsius_to_fahrenheit), &unused_data_1, (GClosureNotify) data_free);
g_closure_set_marshal (c2f_clos, binding_transform_marshal);
f2c_clos = g_cclosure_new (G_CALLBACK (fahrenheit_to_celsius), &unused_data_2, (GClosureNotify) data_free);
g_closure_set_marshal (f2c_clos, binding_transform_marshal);
binding = g_object_bind_property_with_closures (source, "value",
target, "value",
G_BINDING_BIDIRECTIONAL,
c2f_clos,
f2c_clos);
g_object_set (source, "value", 24.0, NULL);
g_assert_cmpfloat (target->value, ==, ((9 * 24.0 / 5) + 32.0));
g_object_set (target, "value", 69.0, NULL);
g_assert_cmpfloat (source->value, ==, (5 * (69.0 - 32.0) / 9));
g_object_unref (source);
g_object_unref (target);
g_assert (unused_data_1);
g_assert (unused_data_2);
}
static void
binding_chain (void)
{
......@@ -407,6 +478,7 @@ main (int argc, char *argv[])
g_test_add_func ("/binding/default", binding_default);
g_test_add_func ("/binding/bidirectional", binding_bidirectional);
g_test_add_func ("/binding/transform", binding_transform);
g_test_add_func ("/binding/transform-closure", binding_transform_closure);
g_test_add_func ("/binding/chain", binding_chain);
g_test_add_func ("/binding/sync-create", binding_sync_create);
......
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