#include "bridge.h"
#include "accessible-register.h"
-/* TODO
- * Need to add concurrency support.
- */
-
#define ATK_BRIDGE_OBJECT_PATH_PREFIX "/org/freedesktop/atspi/accessible"
#define ATK_BRIDGE_OBJECT_REFERENCE_TEMPLATE ATK_BRIDGE_OBJECT_PATH_PREFIX "/%d"
#define ATK_BRIDGE_PATH_PREFIX_LENGTH 33
counter++;
}
-/*---------------------------------------------------------------------------*/
+/*
+ * Returns the reference of the object, or 0 if it is not registered.
+ */
+static guint
+object_to_ref (AtkObject *accessible)
+{
+ return GPOINTER_TO_INT(g_object_get_data (G_OBJECT (accessible), "dbus-id"));
+}
-void
-atk_dbus_foreach_registered(GHFunc func, gpointer data)
+/*
+ * Converts the Accessible object reference to its D-Bus object path
+ */
+static gchar *
+ref_to_path (guint ref)
{
- g_hash_table_foreach(ref2ptr, func, data);
+ return g_strdup_printf(ATK_BRIDGE_OBJECT_REFERENCE_TEMPLATE, ref);
}
/*---------------------------------------------------------------------------*/
/*
- * Called when a registered AtkObject is deleted.
- * Removes the AtkObject from the reference lookup tables.
- * Sets the client side cache to be updated.
+ * Removes the AtkObject from the reference lookup tables, meaning
+ * it is no longer exposed over D-Bus.
*/
static void
-deregister_accessible(gpointer data, GObject *accessible)
+deregister_accessible (guint ref)
{
- guint ref;
- gchar *path;
-
- g_assert(ATK_IS_OBJECT(accessible));
+ g_hash_table_remove(ref2ptr, ref);
+}
+/*
+ * Callback for when a registered AtkObject is destroyed.
+ */
+static void
+deregister_callback (gpointer data, GObject *accessible)
+{
+ guint ref;
+ g_assert (ATK_IS_OBJECT (accessible));
ref = atk_dbus_object_to_ref (ATK_OBJECT(accessible));
-
if (ref != 0)
{
- g_hash_table_remove(ref2ptr, GINT_TO_POINTER(ref));
- /*
- * TODO
- * Pyatspi client side exceptions have occured indicating
- * that an object has been removed twice.
- * This should not be possible and needs investigation.
- */
- spi_emit_cache_removal (ref, atk_adaptor_app_data->bus);
+ deregister_accessible (ref);
}
}
-/*---------------------------------------------------------------------------*/
-
-/* FIXME
- * Horrible hack warning.
- *
- * Problem 1:
- *
- * In an ideal world there would be a signal "Accessible created" that we could
- * use to register all new AtkObjects with D-Bus. The AtkObjects would be
- * created at the time of their implementing widget. This is how things
- * happen in Qt and its damn sensible.
- *
- * In GTK Gail objects are created 'lazily' when they are accessed. This is
- * presumably an optimization to reduce memory. I happen to think its a very
- * very bad one. Anyway, there is no signal, and Gail objects don't get created
- * automatically for each widget, so how do we register AtkObjects with D-Bus?
- *
- * Answer, we have one guaranteed AtkObject, the root. We traverse the tree provided
- * by the root object, registering as we go. When new objects are created we use
- * the children-changed signal of their parent to find out. As we don't know
- * if a new object has any children that have not been registered we must traverse
- * the decendants of every new object to find AtkObjects that have not been registered.
- *
- * Problem 2:
- *
- * For whatever reason events are generated for objects that have not yet been
- * registered with D-Bus. This means that when translating an Atk signal to an
- * AT-SPI one it may be neccessary to register objects first.
- *
- * The caveat is that when registering an object somewhere in the middle of the
- * AtkObject tree there is no guarantee that its parent objects have been registered.
- * So when registering a new object we also need to register its parents back to the
- * root object.
- *
- * Other solutions:
- *
- * The original solution was completely recursive. So when the reference of an AtkObject
- * was requested it would be registered there and then. I didn't like the recursive
- * solution, it was a very very deep stack in some cases.
- *
- */
-
/*
- * This function registers the object so that it is exported
- * over D-Bus and schedules an update to client side cache.
+ * Called to register an AtkObject with AT-SPI and expose it over D-Bus.
*/
-static guint
-export (GList **uplist, AtkObject *accessible)
+static void
+register_accessible (AtkObject *accessible)
{
guint ref;
- gchar *path;
-
g_assert(ATK_IS_OBJECT(accessible));
ref = assign_reference();
g_hash_table_insert (ref2ptr, GINT_TO_POINTER(ref), accessible);
g_object_set_data (G_OBJECT(accessible), "dbus-id", GINT_TO_POINTER(ref));
- g_object_weak_ref(G_OBJECT(accessible), deregister_accessible, NULL);
+ g_object_weak_ref(G_OBJECT(accessible), deregister_callback, NULL);
- *uplist = g_list_prepend (*uplist, accessible);
-
- return ref;
+ *registered = g_list_prepend (*registered, current);
}
+/*---------------------------------------------------------------------------*/
+
+typedef void (*ActionFunc) (GList **, AtkObject *);
+
+/* Return true if action should be performed */
+typedef gboolean (*FilterFunc) (AtkObject *);
+
/*
- * Exports all the dependencies of an AtkObject.
- * This is the subtree and the ancestors.
- *
- * Dependencies are the objects that get included in the
- * cache, and therefore need to be registered before the
- * update signal is sent.
+ * This function performs a depth first traversal of a tree of AtkObjects.
*
- * This does a depth first traversal of a subtree of AtkObject
- * and exports them as Accessible objects if they are not exported
- * already.
+ * It uses a FilterFunc to determine if a node needs to have an action
+ * performed on it.
*
- * It exports all ancestors of the object if they are not
- * exported already.
+ * Nodes that are filtered out become leaves and no recursion is performed on
+ * them.
*/
-static guint
-export_deps (AtkObject *accessible)
+void
+traverse_atk_tree (AtkObject *accessible,
+ GList **visited,
+ ActionFunc action,
+ FilterFunc filter)
{
AtkObject *current, *tmp;
GQueue *stack;
guint i, ref;
gboolean recurse;
-
- /* Export subtree including object itself */
- /*========================================*/
- ref = atk_dbus_object_to_ref (accessible);
- if (ref)
- return ref;
+ if (!filter (accessible))
+ return;
stack = g_queue_new ();
-
current = g_object_ref (accessible);
- ref = export (&uplist, current);
+ action (visited, current)
g_queue_push_head (stack, GINT_TO_POINTER (0));
/*
*/
while (!g_queue_is_empty (stack))
{
- /* This while loop finds the next node that needs processing,
- * if one exists.
- */
+ /* Find the next child node that needs processing */
i = GPOINTER_TO_INT(g_queue_peek_head (stack));
recurse = FALSE;
while (i < atk_object_get_n_accessible_children (current) &&
recurse == FALSE)
{
tmp = atk_object_ref_accessible_child (current, i);
- if (!atk_dbus_object_to_ref (tmp))
+ /* If filter function */
+ if (filter (tmp))
{
recurse = TRUE;
}
g_object_unref (G_OBJECT (tmp));
}
}
+
if (recurse)
{
- /* Still children to process */
+ /* Push onto stack */
current = tmp;
- export (&uplist, current);
- /* Update parent nodes next child index */
+ action (visited, current);
g_queue_peek_head_link (stack)->data = GINT_TO_POINTER (i+1);
- /* Push a new child index for the current node */
g_queue_push_head (stack, GINT_TO_POINTER (0));
}
else
{
- /* No more children, move to parent */
+ /* Pop from stack */
tmp = current;
current = atk_object_get_parent (current);
g_object_unref (G_OBJECT (tmp));
}
}
- /* Export all neccessary ancestors of the object */
- /*===============================================*/
- current = atk_object_get_parent (accessible);
- while (current && !atk_dbus_object_to_ref (current))
- {
- export (&uplist, current);
- }
-
- spi_emit_cache_update (uplist, atk_adaptor_app_data->bus);
- g_list_free (uplist);
return ref;
}
/*---------------------------------------------------------------------------*/
-/* Called to register an AtkObject with AT-SPI and expose it over D-Bus. */
-guint
-atk_dbus_register_accessible (AtkObject *accessible)
-{
- guint ref;
- g_assert(ATK_IS_OBJECT(accessible));
-
- return export_deps (accessible);
-}
-
-/* Called when an already registered object is updated in such a
+/*
+ * Called when an already registered object is updated in such a
* way that client side cache needs to be updated.
*/
-guint
-atk_dbus_update_accessible (AtkObject *accessible)
+static void
+update_accessible (AtkObject *accessible)
{
guint ref = 0;
- GList *uplist = NULL;
g_assert(ATK_IS_OBJECT(accessible));
ref = atk_dbus_object_to_ref (accessible);
if (ref)
{
- uplist = g_list_prepend (uplist, accessible);
- spi_emit_cache_update (uplist, atk_adaptor_app_data->bus);
- g_list_free (uplist);
+ spi_emit_cache_update (accessible, atk_adaptor_app_data->bus);
}
- return ref;
}
/*---------------------------------------------------------------------------*/
-/*
- * Returns the reference of the object, or 0 if it is not exported over D-Bus.
- */
-guint
-atk_dbus_object_to_ref (AtkObject *accessible)
+static gboolean
+register_filter (AtkObject *accessible)
{
- return GPOINTER_TO_INT(g_object_get_data (G_OBJECT (accessible), "dbus-id"));
+ if (object_to_ref (accessible))
+ return TRUE;
+ else
+ return FALSE;
}
-/*
- * Converts the Accessible object reference to its D-Bus object path
- */
-gchar *
-atk_dbus_ref_to_path (guint ref)
+static void
+register_action (GList **registered, AtkObject *accessible)
{
- return g_strdup_printf(ATK_BRIDGE_OBJECT_REFERENCE_TEMPLATE, ref);
+ register_accessible (accessible)
+ *registered = g_list_prepend (*registered, accessible);
+}
+
+static void
+register_foreach (gpointer data, gpointer user_data)
+{
+ spi_emit_cache_update (ATK_OBJECT (data), atk_adaptor_app_data->bus);
+}
+
+static void
+register_subtree (AtkObject *accessible)
+{
+ GList *registered = NULL;
+
+ traverse_atk_tree (accessible,
+ ®istered,
+ (ActionFunc) register_accessible,
+ (FilterFunc) register_filter);
+
+ g_list_foreach (registered, register_foreach);
+}
+
+/*---------------------------------------------------------------------------*/
+
+static gboolean
+deregister_filter (AtkObject *accessible)
+{
+ if (!object_to_ref (accessible))
+ return TRUE;
+ else
+ return FALSE;
+}
+
+static void
+deregister_action (GList **deregistered, AtkObject *accessible)
+{
+ guint ref;
+ g_assert (ATK_IS_OBJECT (accessible));
+
+ ref = atk_dbus_object_to_ref (accessible);
+ if (ref != 0)
+ {
+ deregister_accessible (ref);
+ *deregistered = g_list_prepend (*deregistered, GINT_TO_POINTER(ref));
+ }
+}
+
+static void
+deregister_foreach (gpointer data, gpointer user_data)
+{
+ spi_emit_cache_update (GPOINTER_TO_INT (data), atk_adaptor_app_data->bus);
+}
+
+static void
+deregister_subtree (AtkObject *accessible)
+{
+ GList *deregistered = NULL;
+
+ traverse_atk_tree (accessible,
+ &deregistered,
+ (ActionFunc) deregister_accessible,
+ (FilterFunc) deregister_filter);
+
+ g_list_foreach (deregistered, deregister_foreach);
+}
+
+/*---------------------------------------------------------------------------*/
+
+void
+atk_dbus_foreach_registered(GHFunc func, gpointer data)
+{
+ g_hash_table_foreach(ref2ptr, func, data);
}
/*
return NULL;
}
-
/*
* Used to lookup a D-Bus path from the AtkObject.
*/
/*---------------------------------------------------------------------------*/
/*
+ * Events are not evaluated for non-registered accessibles.
+ *
+ * When a property change is made on a registered accessible
+ * the client side cache should be updated.
+ *
+ * When a parent is changed the subtree is de-registered
+ * if the parent is not attached to the root accessible.
+ */
+static gboolean
+tree_update_listener (GSignalInvocationHint *signal_hint,
+ guint n_param_values,
+ const GValue *param_values,
+ gpointer data)
+{
+ AtkObject *accessible;
+ AtkPropertyValues *values;
+ const gchar *pname = NULL;
+
+ accessible = g_value_get_object (¶m_values[0]);
+ values = (AtkPropertyValues*) g_value_get_pointer (¶m_values[1]);
+
+ pname = values[0].property_name;
+
+ if (!atk_dbus_object_to_ref (accessible))
+ return TRUE;
+
+ if (strcmp (pname, "accessible-name") == 0 ||
+ strcmp (pname, "accessible-description"))
+ {
+ atk_dbus_update_accessible (accessible);
+ }
+ else if (strcmp (pname, "accessible-parent"))
+ {
+ guint ref;
+
+ ref = atk_dbus_object_to_ref;
+ if (!ref)
+ }
+ return TRUE;
+}
+
+/*
+ * Events are not evaluated for non registered accessibles.
+ *
+ * When the children of a registered accessible are changed
+ * the subtree, rooted at the child is registered.
+ */
+static gboolean
+tree_update_children_listener (GSignalInvocationHint *signal_hint,
+ guint n_param_values,
+ const GValue *param_values,
+ gpointer data)
+{
+ AtkObject *accessible;
+ const gchar *detail = NULL;
+ AtkObject *child;
+ gboolean child_needs_unref = FALSE;
+
+ if (signal_hint->detail)
+ detail = g_quark_to_string (signal_hint->detail);
+
+ accessible = g_value_get_object (¶m_values[0]);
+ if (!strcmp (detail, "add"))
+ {
+ gpointer child;
+ int index = g_value_get_uint (param_values + 1);
+ child = g_value_get_pointer (param_values + 2);
+
+ if (ATK_IS_OBJECT (child))
+ g_object_ref (child);
+ else
+ child = atk_object_ref_accessible_child (accessible, index);
+
+ atk_dbus_register_subtree (child);
+ g_object_unref (child);
+ }
+ return TRUE;
+}
+
+/*
* Initializes required global data. The update and removal lists
* and the reference lookup tables.
*
if (!ref2ptr)
ref2ptr = g_hash_table_new(g_direct_hash, g_direct_equal);
- /* Get the root accessible and add */
atk_dbus_register_accessible (root);
+
+ atk_add_global_event_listener (tree_update_listener, "Gtk:AtkObject:property-change");
+ atk_add_global_event_listener (tree_update_children_listener, "Gtk:AtkObject:children-changed");
}
/*END------------------------------------------------------------------------*/
projects / platform / core / uifw / at-spi2-atk.git / blobdiff