#include <stdlib.h>
#include <string.h>
+#include "bridge.h"
#include "accessible.h"
-GHashTable *path2ptr;
-static guint objindex;
+/* 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
+
+/*
+ * This module is responsible for keeping track of all the AtkObjects in
+ * the application, so that they can be accessed remotely and placed in
+ * a client side cache.
+ *
+ * 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
+ * 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 architecture of AT-SPI dbus is such that AtkObjects are not
+ * remotely reference counted. This means that we need to keep track of
+ * object destruction. When an object is destroyed it must be 'deregistered'
+ * To do this lookup we keep a dbus-id attribute on each AtkObject.
+ *
+ * In addition to accessing the objects remotely we must be able to update
+ * 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 each AtkObject that has changed since the
+ * last update. It should also provide a list of objects that have been
+ * removed since the last update.
+ *
+ * To enbale this two hash tables are kept. One keeps a list of AtkObjects
+ * that have been updated. The other a list of objects that have been
+ * removed since the last 'update' signal. The reason they are
+ * stored as hash tables is to ensure that if an AtkObject is removed
+ * and then added between update signals then the object is easy to delete
+ * from the 'update' list without doing a costly lookup.
+ *
+ * The mappings will be called 'reference lookup tables'
+ * The hashtable containing AtkObjects that need updating in the client side
+ * cache will be called the 'update list'
+ * The hashtable containing the AtkObjects that need removing from the client
+ * side cache will be called the 'removal list'
+ */
+
+GHashTable *ref2ptr = NULL; /* Used for converting a D-Bus path (Reference) to the object pointer */
+
+GHashTable *update_list = NULL; /* Stores the objects that need a client side cache update */
+GHashTable *remove_list = NULL; /* Stores the objects that need to be removed from the client side cache */
+
+static guint counter = 1;
+/* Amazingly the ATK event callbacks dont have a user
+ * data parameter. Instead, with great sadness, we use
+ * some global data. Data is declared and initialized
+ * in bridge.c.
+ */
+extern SpiAppData *atk_adaptor_app_data;
+
+/*---------------------------------------------------------------------------*/
+
+/*
+ * Each AtkObject must be asssigned a D-Bus path (Reference)
+ *
+ * This function provides an integer reference for a new
+ * AtkObject.
+ */
+static guint
+assign_reference(void)
+{
+ counter++;
+ /* Reference of 0 not allowed as used as direct key in hash table */
+ if (counter == 0)
+ counter++;
+}
+
+/*---------------------------------------------------------------------------*/
+
+/*
+ * Called when a registered AtkObject is deleted.
+ *
+ * Removes the AtkObject from the reference lookup tables.
+ * Adds the reference of the object to the removal list.
+ */
static void
-deregister_object (gpointer data, GObject *obj)
+deregister_accessible(gpointer data, GObject *accessible)
{
- spi_dbus_notify_remove(ATK_OBJECT(obj), NULL);
- g_hash_table_remove (path2ptr, &obj);
+ guint ref;
+
+ g_assert(ATK_IS_OBJECT(accessible));
+
+
+ ref = GPOINTER_TO_INT(g_object_get_data (accessible, "dbus-id"));
+
+ /* Remove from update list */
+ g_hash_table_remove(update_list, GINT_TO_POINTER(ref));
+
+ if (ref != 0)
+ {
+ g_hash_table_remove(ref2ptr, GINT_TO_POINTER(ref));
+ /* Add to removal list */
+ /*
+ * TODO
+ * Pyatspi client side exceptions have occured indicating
+ * that an object has been removed twice.
+ * This should not be possible and needs investigation.
+ */
+ g_hash_table_insert(remove_list, GINT_TO_POINTER(ref), NULL);
+ }
+
+ atk_tree_cache_needs_update(atk_adaptor_app_data->bus);
}
+/*---------------------------------------------------------------------------*/
+
+/*
+ * Registers a new AtkObject.
+ *
+ * Adds the AtkObject to the reference lookup tables.
+ * Adds the AtkObject to the update list.
+ */
static guint
-register_object (GObject * obj)
+register_accessible (AtkObject *accessible)
+{
+ guint reference;
+
+ g_assert(ATK_IS_OBJECT(accessible));
+
+ reference = assign_reference();
+
+ g_hash_table_insert (ref2ptr, GINT_TO_POINTER(reference), accessible);
+ g_object_set_data (G_OBJECT(accessible), "dbus-id", GINT_TO_POINTER(reference));
+ g_object_weak_ref(G_OBJECT(accessible), deregister_accessible, NULL);
+
+ /* Add to update list */
+ g_hash_table_insert (update_list, GINT_TO_POINTER(reference), accessible);
+
+ atk_tree_cache_needs_update(atk_adaptor_app_data->bus);
+
+ return reference;
+}
+
+/*---------------------------------------------------------------------------*/
+
+/* TODO Turn these into an iterator API - Think about the locking */
+
+void
+atk_dbus_foreach_registered(GHFunc func, gpointer data)
+{
+ g_hash_table_foreach(ref2ptr, func, data);
+}
+
+/*---------------------------------------------------------------------------*/
+
+void
+atk_dbus_foreach_update_list(GHFunc func, gpointer data)
+{
+ g_hash_table_foreach(update_list, func, data);
+ g_hash_table_remove_all(update_list);
+}
+
+/*---------------------------------------------------------------------------*/
+
+void
+atk_dbus_foreach_remove_list(GHFunc func, gpointer data)
+{
+ g_hash_table_foreach(remove_list, func, data);
+ g_hash_table_remove_all(remove_list);
+}
+
+/*---------------------------------------------------------------------------*/
+
+/*
+ * Called on an AtkObject when it has changed in such a way
+ * that the client side cache of the object will need updating.
+ */
+void
+atk_dbus_notify_change(AtkObject *accessible)
{
- gint *new_int;
+ guint ref;
+ g_assert(ATK_IS_OBJECT(accessible));
- if (!path2ptr)
+ if (!g_object_get_data (G_OBJECT (accessible), "dbus-id"))
{
- path2ptr = g_hash_table_new_full (g_int_hash, g_int_equal, g_free, NULL);
- if (!path2ptr)
- return ++objindex;
+ register_accessible(accessible);
}
- objindex++;
- while (g_hash_table_lookup (path2ptr, &objindex))
+ else
{
- objindex++;
- /* g_object_get_data returning 0 means no data, so handle wrap-around */
- if (objindex == 0)
- objindex++;
+ ref = GPOINTER_TO_INT (g_object_get_data (G_OBJECT (accessible), "dbus-id"));
+ g_hash_table_insert (update_list, GINT_TO_POINTER (ref), accessible);
+ atk_tree_cache_needs_update(atk_adaptor_app_data->bus);
}
- new_int = (gint *)g_malloc(sizeof(gint));
- if (new_int)
- {
- *new_int = objindex;
- g_hash_table_insert (path2ptr, new_int, obj);
- }
- g_object_set_data (G_OBJECT (obj), "dbus-id", (gpointer) objindex);
- g_object_weak_ref(G_OBJECT(obj), deregister_object, NULL);
- spi_dbus_notify_change(obj, TRUE, NULL);
- return objindex;
}
+/*---------------------------------------------------------------------------*/
+
+/*
+ * Used to lookup an AtkObject from its D-Bus path.
+ */
AtkObject *
-spi_dbus_get_object (const char *path)
+atk_dbus_get_object (const char *path)
{
guint index;
void *data;
g_assert (path);
- if (strncmp(path, "/org/freedesktop/atspi/accessible", 33) != 0) return NULL;
- path += 33; /* skip over preamble */
- if (path[0] == '\0') return atk_get_root();
- if (path[0] != '/') return NULL;
+
+ if (strncmp(path, ATK_BRIDGE_OBJECT_PATH_PREFIX, ATK_BRIDGE_PATH_PREFIX_LENGTH) != 0)
+ return NULL;
+
+ path += ATK_BRIDGE_PATH_PREFIX_LENGTH; /* Skip over the prefix */
+
+ if (path[0] == '\0')
+ return atk_get_root();
+ if (path[0] != '/')
+ return NULL;
+
path++;
index = atoi (path);
- data = g_hash_table_lookup (path2ptr, &index);
+ data = g_hash_table_lookup (ref2ptr, GINT_TO_POINTER(index));
if (data)
return ATK_OBJECT (data);
- return NULL;
+ else
+ return NULL;
}
+/*---------------------------------------------------------------------------*/
+
gchar *
-spi_dbus_get_path (AtkObject * obj)
+atk_dbus_get_path_from_ref(guint ref)
{
- if (!obj) return NULL;
- guint index = (guint) g_object_get_data (G_OBJECT (obj), "dbus-id");
+ return g_strdup_printf(ATK_BRIDGE_OBJECT_REFERENCE_TEMPLATE, ref);
+}
+
+/*---------------------------------------------------------------------------*/
+
+/*
+ * Used to lookup a D-Bus path from the AtkObject.
+ *
+ * Objects without a path are registered and provided with one.
+ */
+gchar *
+atk_dbus_get_path (AtkObject *accessible)
+{
+ guint index;
+
+ g_assert (accessible);
+
+ index = GPOINTER_TO_INT(g_object_get_data (G_OBJECT (accessible), "dbus-id"));
if (!index)
- index = register_object (obj);
- return g_strdup_printf ("/org/freedesktop/atspi/accessible/%d", index);
+ index = register_accessible(accessible);
+
+ return g_strdup_printf(ATK_BRIDGE_OBJECT_REFERENCE_TEMPLATE, index);
}
-/* Reply with the given object and dereference it if unref is TRUE */
+/*---------------------------------------------------------------------------*/
+
+/*
+ * Used to recursively register accessibles.
+ *
+ * When children are added to an accessible we need to
+ * iterate over the new subtree provided to register new accessibles.
+ */
+guint
+atk_dbus_register_subtree(AtkObject *accessible)
+{
+ AtkObject *child;
+ guint i, n_children;
+ guint ref;
+
+ ref = GPOINTER_TO_INT(g_object_get_data (G_OBJECT (accessible), "dbus-id"));
+ if (!ref)
+ ref = register_accessible(accessible);
+
+ n_children = atk_object_get_n_accessible_children(accessible);
+ for (i=0; i < n_children; i++)
+ {
+ child = atk_object_ref_accessible_child(accessible, i);
+ atk_dbus_register_subtree(child);
+ }
+ return ref;
+}
+
+/*---------------------------------------------------------------------------*/
+
+/*
+ * Marshals a single object into a D-Bus message.
+ *
+ * Unrefs the AtkObject if unref is true.
+ */
DBusMessage *
-spi_dbus_return_object (DBusMessage * message, AtkObject * obj, int unref)
+spi_dbus_return_object (DBusMessage *message, AtkObject *obj, gboolean unref)
{
DBusMessage *reply;
- const char *path = spi_dbus_get_path (obj);
+ gchar *path;
+
+ path = atk_dbus_get_path (obj);
+
if (unref)
g_object_unref (obj);
- if (!path)
- {
- /* Should we have a more specific error for this? */
- return spi_dbus_general_error (message);
- }
+
reply = dbus_message_new_method_return (message);
if (reply)
{
return reply;
}
+/*---------------------------------------------------------------------------*/
+
+/*
+ * Marshals a variant containing the object reference into the message iter
+ * provided.
+ *
+ * Unrefs the object if unref is true.
+ */
dbus_bool_t
-spi_dbus_return_v_object (DBusMessageIter * iter, AtkObject * obj, int unref)
+spi_dbus_return_v_object (DBusMessageIter *iter, AtkObject *obj, int unref)
{
- const char *path = spi_dbus_get_path (obj);
+ char *path;
+
+ path = atk_dbus_get_path (obj);
+
if (unref)
g_object_unref (obj);
- if (!path)
- return FALSE;
+
return droute_return_v_object (iter, path);
}
+/*---------------------------------------------------------------------------*/
+
+/*
+ * Initializes required global data. The update and removal lists
+ * and the reference lookup tables.
+ *
+ * Initializes all of the required D-Bus interfaces.
+ */
void
-spi_dbus_initialize (DRouteData * data)
+atk_dbus_initialize (AtkObject *root)
{
- spi_initialize_accessible (data);
- spi_initialize_action(data);
- spi_initialize_collection (data);
- spi_initialize_component (data);
- spi_initialize_document (data);
- spi_initialize_editabletext (data);
- spi_initialize_hyperlink (data);
- spi_initialize_hypertext (data);
- spi_initialize_image (data);
- spi_initialize_selection (data);
- spi_initialize_table (data);
- spi_initialize_text (data);
- spi_initialize_value (data);
- spi_initialize_introspectable(data, (DRouteGetDatumFunction) spi_dbus_get_object);
+ if (!ref2ptr)
+ ref2ptr = g_hash_table_new(g_direct_hash, g_direct_equal);
+ if (!update_list)
+ update_list = g_hash_table_new(g_direct_hash, g_direct_equal);
+ if (!remove_list)
+ remove_list = g_hash_table_new(g_direct_hash, g_direct_equal);
+
+ /* Get the root accessible and add */
+ atk_dbus_register_subtree(root);
}
-static GString *
-spi_get_tree (AtkObject * obj, GString * str, DRouteData * data)
-{
- int role;
- const char *name;
- gchar *path;
- GSList *l;
- gint childcount;
- gint i;
+/*END------------------------------------------------------------------------*/
- if (!obj)
- return NULL;
- role = spi_accessible_role_from_atk_role (atk_object_get_role (obj));;
- name = atk_object_get_name (obj);
- if (!name)
- name = "";
- path = spi_dbus_get_path (obj);
- g_string_append_printf (str,
- "<object path=\"%s\" name=\"%s\" role=\"%d\">\n",
- path, name, role);
- for (l = data->interfaces; l; l = g_slist_next (l))
- {
- DRouteInterface *iface_def = (DRouteInterface *) l->data;
- void *datum = NULL;
- if (iface_def->get_datum)
- datum = (*iface_def->get_datum) (path, data->user_data);
- if (datum)
- {
- g_string_append_printf (str, "<interface name=\"%s\"/>\n",
- iface_def->name);
- if (iface_def->free_datum)
- (*iface_def->free_datum) (datum);
- }
- }
- childcount = atk_object_get_n_accessible_children (obj);
- for (i = 0; i < childcount; i++)
- {
- AtkObject *child = atk_object_ref_accessible_child (obj, i);
- str = spi_get_tree (child, str, data);
- g_object_unref (child);
- }
- str = g_string_append (str, "</object>\n");
- return str;
-}
projects / platform / core / uifw / at-spi2-atk.git / blobdiff