* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
- * version 2 of the License, or (at your option) any later version.
+ * version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
typedef struct
{
- volatile gint ref_count;
+ gint ref_count; /* (atomic) */
guint id;
gchar *name;
GBusNameWatcherFlags flags;
} Client;
/* Must be accessed atomically. */
-static volatile guint next_global_id = 1;
+static guint next_global_id = 1; /* (atomic) */
/* Must be accessed with @lock held. */
static GHashTable *map_id_to_client = NULL;
static void
actually_do_call (Client *client, GDBusConnection *connection, const gchar *name_owner, CallType call_type)
{
+ /* The client might have been cancelled (g_bus_unwatch_name()) while we were
+ * sitting in the #GMainContext dispatch queue. */
+ if (client->cancelled)
+ return;
+
switch (call_type)
{
case CALL_TYPE_NAME_APPEARED:
call_in_idle_cb,
data,
(GDestroyNotify) call_handler_data_free);
- g_source_set_name (idle_source, "[gio] call_in_idle_cb");
+ g_source_set_name (idle_source, "[gio, gdbusnamewatching.c] call_in_idle_cb");
g_source_attach (idle_source, client->main_context);
g_source_unref (idle_source);
}
}
static void
-call_vanished_handler (Client *client,
- gboolean ignore_cancelled)
+call_vanished_handler (Client *client)
{
if (client->previous_call != PREVIOUS_CALL_VANISHED)
{
client->previous_call = PREVIOUS_CALL_VANISHED;
- if (((!client->cancelled) || ignore_cancelled) && client->name_vanished_handler != NULL)
+ if (!client->cancelled && client->name_vanished_handler != NULL)
{
do_call (client, CALL_TYPE_NAME_VANISHED);
}
/* ---------------------------------------------------------------------------------------------------- */
+/* Return a reference to the #Client for @watcher_id, or %NULL if it’s been
+ * unwatched. This is safe to call from any thread. */
+static Client *
+dup_client (guint watcher_id)
+{
+ Client *client;
+
+ G_LOCK (lock);
+
+ g_assert (watcher_id != 0);
+ g_assert (map_id_to_client != NULL);
+
+ client = g_hash_table_lookup (map_id_to_client, GUINT_TO_POINTER (watcher_id));
+
+ if (client != NULL)
+ client_ref (client);
+
+ G_UNLOCK (lock);
+
+ return client;
+}
+
+/* Could be called from any thread, so it could be called after client_unref()
+ * has started finalising the #Client. Avoid that by looking up the #Client
+ * atomically. */
static void
on_connection_disconnected (GDBusConnection *connection,
gboolean remote_peer_vanished,
GError *error,
gpointer user_data)
{
- Client *client = user_data;
+ guint watcher_id = GPOINTER_TO_UINT (user_data);
+ Client *client = NULL;
+
+ client = dup_client (watcher_id);
+ if (client == NULL)
+ return;
if (client->name_owner_changed_subscription_id > 0)
g_dbus_connection_signal_unsubscribe (client->connection, client->name_owner_changed_subscription_id);
client->name_owner_changed_subscription_id = 0;
client->connection = NULL;
- call_vanished_handler (client, FALSE);
+ call_vanished_handler (client);
+
+ client_unref (client);
}
/* ---------------------------------------------------------------------------------------------------- */
+/* Will always be called from the thread which acquired client->main_context. */
static void
on_name_owner_changed (GDBusConnection *connection,
const gchar *sender_name,
GVariant *parameters,
gpointer user_data)
{
- Client *client = user_data;
+ guint watcher_id = GPOINTER_TO_UINT (user_data);
+ Client *client = NULL;
const gchar *name;
const gchar *old_owner;
const gchar *new_owner;
+ client = dup_client (watcher_id);
+ if (client == NULL)
+ return;
+
if (!client->initialized)
goto out;
{
g_free (client->name_owner);
client->name_owner = NULL;
- call_vanished_handler (client, FALSE);
+ call_vanished_handler (client);
}
if (new_owner != NULL && strlen (new_owner) > 0)
}
out:
- ;
+ client_unref (client);
}
/* ---------------------------------------------------------------------------------------------------- */
}
else
{
- call_vanished_handler (client, FALSE);
+ call_vanished_handler (client);
}
client->initialized = TRUE;
else
{
g_warning ("Unexpected reply %d from StartServiceByName() method", start_service_result);
- call_vanished_handler (client, FALSE);
+ call_vanished_handler (client);
client->initialized = TRUE;
}
}
client->disconnected_signal_handler_id = g_signal_connect (client->connection,
"closed",
G_CALLBACK (on_connection_disconnected),
- client);
+ GUINT_TO_POINTER (client->id));
/* start listening to NameOwnerChanged messages immediately */
client->name_owner_changed_subscription_id = g_dbus_connection_signal_subscribe (client->connection,
client->name,
G_DBUS_SIGNAL_FLAGS_NONE,
on_name_owner_changed,
- client,
+ GUINT_TO_POINTER (client->id),
NULL);
if (client->flags & G_BUS_NAME_WATCHER_FLAGS_AUTO_START)
client->connection = g_bus_get_finish (res, NULL);
if (client->connection == NULL)
{
- call_vanished_handler (client, FALSE);
+ call_vanished_handler (client);
goto out;
}
*
* Starts watching @name on the bus specified by @bus_type and calls
* @name_appeared_handler and @name_vanished_handler when the name is
- * known to have a owner respectively known to lose its
+ * known to have an owner respectively known to lose its
* owner. Callbacks will be invoked in the
* [thread-default main context][g-main-context-push-thread-default]
* of the thread you are calling this function from.
* @name_appeared_handler and destroy them again (if any) in
* @name_vanished_handler.
*
- * Returns: An identifier (never 0) that an be used with
+ * Returns: An identifier (never 0) that can be used with
* g_bus_unwatch_name() to stop watching the name.
*
* Since: 2.26
client = g_new0 (Client, 1);
client->ref_count = 1;
- client->id = g_atomic_int_add (&next_global_id, 1); /* TODO: uh oh, handle overflow */
+ client->id = (guint) g_atomic_int_add (&next_global_id, 1); /* TODO: uh oh, handle overflow */
client->name = g_strdup (name);
client->flags = flags;
client->name_appeared_handler = name_appeared_handler;
* Like g_bus_watch_name() but takes a #GDBusConnection instead of a
* #GBusType.
*
- * Returns: An identifier (never 0) that an be used with
+ * Returns: An identifier (never 0) that can be used with
* g_bus_unwatch_name() to stop watching the name.
*
* Since: 2.26
client = g_new0 (Client, 1);
client->ref_count = 1;
- client->id = g_atomic_int_add (&next_global_id, 1); /* TODO: uh oh, handle overflow */
+ client->id = (guint) g_atomic_int_add (&next_global_id, 1); /* TODO: uh oh, handle overflow */
client->name = g_strdup (name);
client->flags = flags;
client->name_appeared_handler = name_appeared_handler;
* Version of g_bus_watch_name() using closures instead of callbacks for
* easier binding in other languages.
*
- * Returns: An identifier (never 0) that an be used with
+ * Returns: An identifier (never 0) that can be used with
* g_bus_unwatch_name() to stop watching the name.
*
* Since: 2.26
* Version of g_bus_watch_name_on_connection() using closures instead of callbacks for
* easier binding in other languages.
*
- * Returns: An identifier (never 0) that an be used with
+ * Returns: An identifier (never 0) that can be used with
* g_bus_unwatch_name() to stop watching the name.
*
* Since: 2.26
*
* Stops watching a name.
*
+ * Note that there may still be D-Bus traffic to process (relating to watching
+ * and unwatching the name) in the current thread-default #GMainContext after
+ * this function has returned. You should continue to iterate the #GMainContext
+ * until the #GDestroyNotify function passed to g_bus_watch_name() is called, in
+ * order to avoid memory leaks through callbacks queued on the #GMainContext
+ * after it’s stopped being iterated.
+ *
* Since: 2.26
*/
void
projects / platform / upstream / glib.git / blobdiff