#include "bridge.h"
#include "accessible-register.h"
-#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
-
/*
* This module is responsible for keeping track of all the AtkObjects in
* the application, so that they can be accessed remotely and placed in
*
* To access an AtkObject remotely we need to provide a D-Bus object
* path for it. The D-Bus object paths used have a standard prefix
- * (ATK_BRIDGE_OBJECT_PATH_PREFIX). Appended to this prefix is a string
+ * (SPI_ATK_OBJECT_PATH_PREFIX). Appended to this prefix is a string
* representation of an integer reference. So to access an AtkObject
* remotely we keep a Hashtable that maps the given reference to
* the AtkObject pointer. An object in this hash table is said to be 'registered'.
* the client side cache. This is done using the 'update' signal of the
* org.freedesktop.atspi.Tree interface. The update signal should send out
* all of the cacheable data for an Accessible object.
+ *
+ */
+
+/*
+ * FIXME
+ *
+ * This code seems very brittle.
+ * I would prefer changes to be made to
+ * gail and the ATK interface so that all Accessible
+ * objects are registered with an exporting module.
+ *
+ * This is the same system as Qt has with the QAccessibleBridge
+ * and QAccessibleBridgePlugin. It entails some rather
+ * large structural changes to ATK though:
+ *
+ * Removing infinite spaces (Child access no longer references child).
+ * Removing lazy creation of accessible objects.
*/
-GHashTable *ref2ptr = NULL; /* Used for converting a D-Bus path (Reference) to the object pointer */
+#define SPI_ATK_OBJECT_PATH_PREFIX "/org/freedesktop/atspi/accessible"
+#define SPI_ATK_OBJECT_PATH_DESKTOP "/root"
+
+#define SPI_ATK_PATH_PREFIX_LENGTH 33
+#define SPI_ATK_OBJECT_REFERENCE_TEMPLATE SPI_ATK_OBJECT_PATH_PREFIX "/%d"
+
+
+static GHashTable *ref2ptr = NULL; /* Used for converting a D-Bus path (Reference) to the object pointer */
+
+static guint reference_counter = 0;
+
+static GStaticRecMutex registration_mutex = G_STATIC_REC_MUTEX_INIT;
+
+/*---------------------------------------------------------------------------*/
+
+static GStaticMutex recursion_check_guard = G_STATIC_MUTEX_INIT;
+static gboolean recursion_check = FALSE;
-static guint counter = 1;
+static gboolean
+recursion_check_and_set ()
+{
+ gboolean ret;
+ g_static_mutex_lock (&recursion_check_guard);
+ ret = recursion_check;
+ recursion_check = TRUE;
+ g_static_mutex_unlock (&recursion_check_guard);
+ return ret;
+}
+
+static void
+recursion_check_unset ()
+{
+ g_static_mutex_lock (&recursion_check_guard);
+ recursion_check = FALSE;
+ g_static_mutex_unlock (&recursion_check_guard);
+}
/*---------------------------------------------------------------------------*/
static guint
assign_reference(void)
{
- counter++;
+ reference_counter++;
/* Reference of 0 not allowed as used as direct key in hash table */
- if (counter == 0)
- counter++;
+ if (reference_counter == 0)
+ reference_counter++;
+ return reference_counter;
}
/*
static gchar *
ref_to_path (guint ref)
{
- return g_strdup_printf(ATK_BRIDGE_OBJECT_REFERENCE_TEMPLATE, ref);
+ return g_strdup_printf(SPI_ATK_OBJECT_REFERENCE_TEMPLATE, ref);
}
/*---------------------------------------------------------------------------*/
/*
+ * Callback for when a registered AtkObject is destroyed.
+ *
* Removes the AtkObject from the reference lookup tables, meaning
* it is no longer exposed over D-Bus.
*/
static void
-deregister_accessible (guint ref)
-{
- g_hash_table_remove(ref2ptr, GINT_TO_POINTER(ref));
-}
-
-/*
- * Callback for when a registered AtkObject is destroyed.
- */
-static void
-deregister_callback (gpointer data, GObject *accessible)
+deregister_accessible (gpointer data, GObject *accessible)
{
guint ref;
- g_assert (ATK_IS_OBJECT (accessible));
+ g_return_if_fail (ATK_IS_OBJECT (accessible));
ref = object_to_ref (ATK_OBJECT(accessible));
if (ref != 0)
{
- deregister_accessible (ref);
+ g_hash_table_remove(ref2ptr, GINT_TO_POINTER(ref));
}
}
register_accessible (AtkObject *accessible)
{
guint ref;
- g_assert(ATK_IS_OBJECT(accessible));
+ g_return_if_fail (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_callback, NULL);
+ g_object_weak_ref(G_OBJECT(accessible), deregister_accessible, NULL);
}
/*---------------------------------------------------------------------------*/
-typedef void (*ActionFunc) (GList **, AtkObject *);
-
-/* Return true if action should be performed */
-typedef gboolean (*FilterFunc) (AtkObject *);
-
+#ifdef SPI_ATK_DEBUG
/*
- * This function performs a depth first traversal of a tree of AtkObjects.
+ * This function checks that the ref-count of an accessible
+ * is greater than 1.
*
- * It uses a FilterFunc to determine if a node needs to have an action
- * performed on it.
+ * There is not currently any remote reference counting
+ * in AT-SPI D-Bus so objects that are remotely owned are not
+ * allowed.
*
- * Nodes that are filtered out become leaves and no recursion is performed on
- * them.
+ * TODO Add debug wrapper
*/
-void
-traverse_atk_tree (AtkObject *accessible,
- GList **visited,
- ActionFunc action,
- FilterFunc filter)
+static gboolean
+non_owned_accessible (AtkObject *accessible)
{
- AtkObject *current, *tmp;
- GQueue *stack;
- guint i;
- gboolean recurse;
-
- if (filter (accessible))
- return;
-
- stack = g_queue_new ();
- current = g_object_ref (accessible);
- action (visited, current);
- g_queue_push_head (stack, GINT_TO_POINTER (0));
-
- /*
- * The index held on the stack is the next child node
- * that needs processing at the corresponding level in the tree.
- */
- while (!g_queue_is_empty (stack))
+ if ((G_OBJECT (accessible))->ref_count <= 1)
+ {
+ g_warning ("AT-SPI: Child referenced that is not owned by its parent");
+ return TRUE;
+ }
+ else
+ {
+ return FALSE;
+ }
+}
+#endif /* SPI_ATK_DEBUG */
+
+/*---------------------------------------------------------------------------*/
+
+static gboolean
+has_manages_descendants (AtkObject *accessible)
+{
+ AtkStateSet *state;
+ gboolean result = FALSE;
+
+ /* This is dangerous, refing the state set
+ * seems to do wierd things to the tree & cause recursion
+ * by modifying the tree alot.
+ */
+ state = atk_object_ref_state_set (accessible);
+ if (atk_state_set_contains_state (state, ATK_STATE_MANAGES_DESCENDANTS))
+ {
+#ifdef SPI_ATK_DEBUG
+ g_warning ("AT-SPI: Object with 'Manages descendants' states not currently handled by AT-SPI");
+#endif
+ result = TRUE;
+ }
+ g_object_unref (state);
+
+ return result;
+}
+
+static void
+append_children (AtkObject *accessible, GQueue *traversal)
+{
+ AtkObject *current;
+ guint i;
+
+ for (i =0; i < atk_object_get_n_accessible_children (accessible); i++)
{
- /* 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)
+ current = atk_object_ref_accessible_child (accessible, i);
+ if (current)
{
- tmp = atk_object_ref_accessible_child (current, i);
- /* If filter function */
- if (!filter (tmp))
- {
- recurse = TRUE;
- }
+#ifdef SPI_ATK_DEBUG
+ non_owned_accessible (current);
+#endif
+ if (!has_manages_descendants (current))
+ g_queue_push_tail (traversal, current);
else
- {
- i++;
- g_object_unref (G_OBJECT (tmp));
- }
+ g_object_unref (G_OBJECT (current));
}
+ }
+}
- if (recurse)
- {
- /* Push onto stack */
- current = tmp;
- action (visited, current);
- g_queue_peek_head_link (stack)->data = GINT_TO_POINTER (i+1);
- g_queue_push_head (stack, GINT_TO_POINTER (0));
- }
- else
+/*
+ * Registers a subtree of accessible objects
+ * rooted at the accessible object provided.
+ *
+ * The leaf nodes do not have their children
+ * registered. A node is considered a leaf
+ * if it has the state "manages-descendants"
+ * or if it has already been registered.
+ */
+void
+register_subtree (AtkObject *accessible)
+{
+ AtkObject *current;
+ GQueue *traversal;
+ GQueue *emit_update;
+
+ g_return_if_fail (ATK_IS_OBJECT (accessible));
+
+ traversal = g_queue_new ();
+ emit_update = g_queue_new ();
+
+ g_object_ref (accessible);
+ g_queue_push_tail (traversal, accessible);
+
+ while (!g_queue_is_empty (traversal))
+ {
+ current = g_queue_pop_head (traversal);
+ g_queue_push_tail (emit_update, current);
+ if (!object_to_ref (current))
{
- /* Pop from stack */
- tmp = current;
- current = atk_object_get_parent (current);
- g_object_unref (G_OBJECT (tmp));
- g_queue_pop_head (stack);
+ register_accessible (current);
+#ifdef SPI_ATK_DEBUG
+ g_debug ("REG - %s - %d - %s", atk_object_get_name (current),
+ atk_object_get_role (current),
+ atk_dbus_object_to_path (current));
+#endif
+ append_children (current, traversal);
}
}
+
+ while (!g_queue_is_empty (emit_update))
+ {
+ current = g_queue_pop_head (emit_update);
+ spi_emit_cache_update (current, atk_adaptor_app_data->bus);
+ g_object_unref (G_OBJECT (current));
+ }
+
+ g_queue_free (traversal);
+ g_queue_free (emit_update);
}
/*---------------------------------------------------------------------------*/
update_accessible (AtkObject *accessible)
{
guint ref = 0;
- g_assert(ATK_IS_OBJECT(accessible));
+ g_return_if_fail (ATK_IS_OBJECT(accessible));
ref = object_to_ref (accessible);
if (ref)
/*---------------------------------------------------------------------------*/
-static gboolean
-register_filter (AtkObject *accessible)
-{
- if (object_to_ref (accessible))
- return TRUE;
- else
- return FALSE;
-}
-
-static void
-register_action (GList **registered, AtkObject *accessible)
-{
- 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_action,
- (FilterFunc) register_filter);
-
- g_list_foreach (registered, register_foreach, NULL);
-}
-
-
-static void
-register_ancestors (AtkObject *accessible)
-{
- AtkObject *current;
- guint ref;
- GList *registered = NULL;
-
- current = atk_object_get_parent (accessible);
- while (current)
- {
- ref = atk_dbus_ref_from_object (current);
- if (!ref)
- register_action (®istered, current);
- current = atk_object_get_parent (accessible);
- }
-
- g_list_foreach (registered, register_foreach, NULL);
-}
-
-/*---------------------------------------------------------------------------*/
-
void
atk_dbus_foreach_registered(GHFunc func, gpointer data)
{
guint index;
void *data;
- g_assert (path);
+ g_return_val_if_fail (path, NULL);
- if (strncmp(path, ATK_BRIDGE_OBJECT_PATH_PREFIX, ATK_BRIDGE_PATH_PREFIX_LENGTH) != 0)
+ if (strncmp(path, SPI_ATK_OBJECT_PATH_PREFIX, SPI_ATK_PATH_PREFIX_LENGTH) != 0)
return NULL;
- path += ATK_BRIDGE_PATH_PREFIX_LENGTH; /* Skip over the prefix */
+ path += SPI_ATK_PATH_PREFIX_LENGTH; /* Skip over the prefix */
- if (path[0] == '\0')
+ if (!g_strcmp0 (SPI_ATK_OBJECT_PATH_DESKTOP, path))
return atk_get_root();
if (path[0] != '/')
return NULL;
}
/*
+ * TODO WARNING HACK This function is dangerous.
+ * It should only be called before sending an event on an
+ * object that has not already been registered.
+ */
+gchar *
+atk_dbus_object_attempt_registration (AtkObject *accessible)
+{
+ guint ref;
+
+ ref = object_to_ref (accessible);
+ if (!ref)
+ {
+ /* See if the object is attached to the main tree */
+ AtkObject *current, *prev = NULL;
+ guint cref = 0;
+
+ /* This should iterate until it hits a NULL or registered parent */
+ prev = accessible;
+ current = atk_object_get_parent (accessible);
+ if (current)
+ cref = object_to_ref (current);
+ while (current && !cref)
+ {
+ prev = current;
+ current = atk_object_get_parent (current);
+ if (current)
+ cref = object_to_ref (current);
+ }
+
+ /* A registered parent, with non-registered child, has been found */
+ if (current)
+ {
+ register_subtree (prev);
+ }
+
+ /* The object SHOULD be registered now. If it isn't - I give up */
+ ref = object_to_ref (accessible);
+ if (ref)
+ {
+ return ref_to_path (ref);
+ }
+ else
+ {
+#ifdef SPI_ATK_DEBUG
+ g_debug ("AT-SPI: Could not register a non-attached accessible object");
+#endif
+ return NULL;
+ }
+ }
+ else
+ {
+ return ref_to_path (ref);
+ }
+}
+
+
+/*
* Used to lookup a D-Bus path from the AtkObject.
*/
gchar *
atk_dbus_object_to_path (AtkObject *accessible)
{
guint ref;
- g_assert(ATK_IS_OBJECT(accessible));
ref = object_to_ref (accessible);
if (!ref)
return ref_to_path (ref);
}
+gchar *
+atk_dbus_desktop_object_path ()
+{
+ return g_strdup (SPI_ATK_OBJECT_PATH_PREFIX SPI_ATK_OBJECT_PATH_DESKTOP);
+}
+
/*---------------------------------------------------------------------------*/
+typedef gboolean (*TreeUpdateAction) (GSignalInvocationHint *signal_hint,
+ guint n_param_values,
+ const GValue *param_values,
+ gpointer data,
+ AtkObject *accessible);
+
/*
* Events are not evaluated for non-registered accessibles.
*
* When a parent is changed the subtree is de-registered
* if the parent is not attached to the root accessible.
*/
+/* TODO Turn this function into a macro? */
static gboolean
-tree_update_listener (GSignalInvocationHint *signal_hint,
- guint n_param_values,
- const GValue *param_values,
- gpointer data)
+tree_update_wrapper (GSignalInvocationHint *signal_hint,
+ guint n_param_values,
+ const GValue *param_values,
+ gpointer data,
+ TreeUpdateAction action)
{
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;
+ g_static_rec_mutex_lock (®istration_mutex);
- if (!object_to_ref (accessible))
- return TRUE;
+ /* Ensure that only registered accessibles
+ * have their signals processed.
+ */
+ accessible = ATK_OBJECT(g_value_get_object (¶m_values[0]));
+ g_return_val_if_fail (ATK_IS_OBJECT (accessible), TRUE);
- if (strcmp (pname, "accessible-name") == 0 ||
- strcmp (pname, "accessible-description"))
+ if (object_to_ref (accessible))
{
- atk_dbus_update_accessible (accessible);
- }
- else if (strcmp (pname, "accessible-parent"))
- {
- register_ancestors (accessible);
+#ifdef SPI_ATK_DEBUG
+ if (recursion_check_and_set ())
+ g_warning ("AT-SPI: Recursive use of registration module");
+
+ g_debug ("AT-SPI: Tree update listener");
+#endif
+ action (signal_hint, n_param_values, param_values, data, accessible);
+
+ recursion_check_unset ();
}
+
+ g_static_rec_mutex_unlock (®istration_mutex);
+
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_state_action (GSignalInvocationHint *signal_hint,
+ guint n_param_values,
+ const GValue *param_values,
+ gpointer data,
+ AtkObject *accessible)
+{
+ update_accessible (accessible);
+}
+
+static gboolean
+tree_update_state_listener (GSignalInvocationHint *signal_hint,
+ guint n_param_values,
+ const GValue *param_values,
+ gpointer data)
+{
+ tree_update_wrapper (signal_hint, n_param_values, param_values, data, tree_update_state_action);
+}
+
+static gboolean
+tree_update_property_action (GSignalInvocationHint *signal_hint,
+ guint n_param_values,
+ const GValue *param_values,
+ gpointer data,
+ AtkObject *accessible)
+{
+ AtkPropertyValues *values;
+ const gchar *pname = NULL;
+
+ values = (AtkPropertyValues*) g_value_get_pointer (¶m_values[1]);
+ pname = values[0].property_name;
+ if (strcmp (pname, "accessible-name") == 0 ||
+ strcmp (pname, "accessible-description") == 0 ||
+ strcmp (pname, "accessible-parent") == 0)
+ {
+ update_accessible (accessible);
+ }
+ /* Parent value us updated by child-add signal of parent object */
+}
+
+static gboolean
+tree_update_property_listener (GSignalInvocationHint *signal_hint,
+ guint n_param_values,
+ const GValue *param_values,
+ gpointer data)
+{
+ tree_update_wrapper (signal_hint, n_param_values, param_values, data, tree_update_property_action);
+}
+
+static gboolean
+tree_update_children_action (GSignalInvocationHint *signal_hint,
+ guint n_param_values,
+ const GValue *param_values,
+ gpointer data,
+ AtkObject *accessible)
+{
+ const gchar *detail = NULL;
+ AtkObject *child;
+
+ if (signal_hint->detail)
+ detail = g_quark_to_string (signal_hint->detail);
+
+ 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))
+ {
+ child = atk_object_ref_accessible_child (accessible, index);
+#ifdef SPI_ATK_DEBUG
+ non_owned_accessible (child);
+#endif
+ }
+ register_subtree (child);
+ update_accessible (accessible);
+ }
+}
+
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;
+ tree_update_wrapper (signal_hint, n_param_values, param_values, data, tree_update_children_action);
+}
+
+/*---------------------------------------------------------------------------*/
+
+static void
+spi_atk_register_toplevel_added (AtkObject *accessible,
+ guint index,
+ AtkObject *child)
+{
+ g_static_rec_mutex_lock (®istration_mutex);
- if (signal_hint->detail)
- detail = g_quark_to_string (signal_hint->detail);
+ g_return_if_fail (ATK_IS_OBJECT (accessible));
- accessible = g_value_get_object (¶m_values[0]);
- if (!strcmp (detail, "add"))
+ if (object_to_ref (accessible))
{
- gpointer child;
- int index = g_value_get_uint (param_values + 1);
- child = g_value_get_pointer (param_values + 2);
+#ifdef SPI_ATK_DEBUG
+ if (recursion_check_and_set ())
+ g_warning ("AT-SPI: Recursive use of registration module");
- if (ATK_IS_OBJECT (child))
- g_object_ref (child);
- else
+ g_debug ("AT-SPI: Toplevel added listener");
+#endif
+ if (!ATK_IS_OBJECT (child))
+ {
child = atk_object_ref_accessible_child (accessible, index);
-
+#ifdef SPI_ATK_DEBUG
+ non_owned_accessible (child);
+#endif
+ }
register_subtree (child);
- g_object_unref (child);
+ update_accessible (accessible);
+
+ recursion_check_unset ();
}
- return TRUE;
+
+ g_static_rec_mutex_unlock (®istration_mutex);
+}
+
+static void
+spi_atk_register_toplevel_removed (AtkObject *accessible,
+ guint index,
+ AtkObject *child)
+{
+ g_static_rec_mutex_lock (®istration_mutex);
+
+ g_return_if_fail (ATK_IS_OBJECT (accessible));
+
+ if (object_to_ref (accessible))
+ {
+#ifdef SPI_ATK_DEBUG
+ if (recursion_check_and_set ())
+ g_warning ("AT-SPI: Recursive use of registration module");
+
+ g_debug ("AT-SPI: Toplevel removed listener");
+#endif
+ update_accessible (accessible);
+ recursion_check_unset ();
+ }
+
+ g_static_rec_mutex_unlock (®istration_mutex);
}
/*
if (!ref2ptr)
ref2ptr = g_hash_table_new(g_direct_hash, g_direct_equal);
+#ifdef SPI_ATK_DEBUG
+ if (g_thread_supported ())
+ g_message ("AT-SPI: Threads enabled");
+
+ g_debug ("AT-SPI: Initial Atk tree regisration");
+#endif
+
register_subtree (root);
- atk_add_global_event_listener (tree_update_listener, "Gtk:AtkObject:property-change");
+ atk_add_global_event_listener (tree_update_property_listener, "Gtk:AtkObject:property-change");
atk_add_global_event_listener (tree_update_children_listener, "Gtk:AtkObject:children-changed");
+ atk_add_global_event_listener (tree_update_state_listener, "Gtk:AtkObject:state-change");
+
+ g_signal_connect (root,
+ "children-changed::add",
+ (GCallback) spi_atk_register_toplevel_added,
+ NULL);
+ g_signal_connect (root,
+ "children-changed::remove",
+ (GCallback) spi_atk_register_toplevel_removed,
+ NULL);
}
/*END------------------------------------------------------------------------*/
-
projects / platform / core / uifw / at-spi2-atk.git / blobdiff