* 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General
- * Public License along with this library; if not, write to the
- * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
- * Boston, MA 02111-1307, USA.
+ * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
*
* Author: David Zeuthen <davidz@redhat.com>
*/
#include "gdbusconnection.h"
#include "glibintl.h"
-#include "gioalias.h"
/**
* SECTION:gdbusnamewatching
*
* Convenience API for watching bus names.
*
- * <example id="gdbus-watching-names"><title>Simple application watching a name</title><programlisting><xi:include xmlns:xi="http://www.w3.org/2001/XInclude" parse="text" href="../../../../gio/tests/gdbus-example-watch-name.c"><xi:fallback>FIXME: MISSING XINCLUDE CONTENT</xi:fallback></xi:include></programlisting></example>
+ * A simple example for watching a name can be found in
+ * [gdbus-example-watch-name.c](https://git.gnome.org/browse/glib/tree/gio/tests/gdbus-example-watch-name.c)
*/
G_LOCK_DEFINE_STATIC (lock);
typedef struct
{
- volatile gint ref_count;
+ gint ref_count; /* (atomic) */
guint id;
gchar *name;
GBusNameWatcherFlags flags;
gboolean initialized;
} Client;
-static guint next_global_id = 1;
+/* Must be accessed atomically. */
+static guint next_global_id = 1; /* (atomic) */
+
+/* Must be accessed with @lock held. */
static GHashTable *map_id_to_client = NULL;
static Client *
}
g_free (client->name);
g_free (client->name_owner);
- if (client->main_context != NULL)
- g_main_context_unref (client->main_context);
+ g_main_context_unref (client->main_context);
if (client->user_data_free_func != NULL)
client->user_data_free_func (client->user_data);
g_free (client);
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, gdbusnamewatching.c] call_in_idle_cb");
g_source_attach (idle_source, client->main_context);
g_source_unref (idle_source);
}
static void
do_call (Client *client, CallType call_type)
{
+ GMainContext *current_context;
+
/* only schedule in idle if we're not in the right thread */
- if (g_main_context_get_thread_default () != client->main_context)
+ current_context = g_main_context_ref_thread_default ();
+ if (current_context != client->main_context)
schedule_call_in_idle (client, call_type);
else
actually_do_call (client, client->connection, client->name_owner, call_type);
+ g_main_context_unref (current_context);
}
static void
}
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;
"org.freedesktop.DBus", /* interface name */
"GetNameOwner", /* method name */
g_variant_new ("(s)", client->name),
+ G_VARIANT_TYPE ("(s)"),
G_DBUS_CALL_FLAGS_NONE,
-1,
NULL,
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,
"NameOwnerChanged", /* signal */
"/org/freedesktop/DBus", /* path */
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)
"org.freedesktop.DBus", /* interface name */
"StartServiceByName", /* method name */
g_variant_new ("(su)", client->name, 0),
+ G_VARIANT_TYPE ("(u)"),
G_DBUS_CALL_FLAGS_NONE,
-1,
NULL,
client->connection = g_bus_get_finish (res, NULL);
if (client->connection == NULL)
{
- call_vanished_handler (client, FALSE);
+ call_vanished_handler (client);
goto out;
}
* @bus_type: The type of bus to watch a name on.
* @name: The name (well-known or unique) to watch.
* @flags: Flags from the #GBusNameWatcherFlags enumeration.
- * @name_appeared_handler: Handler to invoke when @name is known to exist or %NULL.
- * @name_vanished_handler: Handler to invoke when @name is known to not exist or %NULL.
+ * @name_appeared_handler: (nullable): Handler to invoke when @name is known to exist or %NULL.
+ * @name_vanished_handler: (nullable): Handler to invoke when @name is known to not exist or %NULL.
* @user_data: User data to pass to handlers.
- * @user_data_free_func: Function for freeing @user_data or %NULL.
+ * @user_data_free_func: (nullable): Function for freeing @user_data or %NULL.
*
* 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
- * owner. Callbacks will be invoked in the <link
- * linkend="g-main-context-push-thread-default">thread-default main
- * loop</link> of the thread you are calling this function from.
+ * 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.
*
* You are guaranteed that one of the handlers will be invoked after
* calling this function. When you are done watching the name, just
* guaranteed that the next time one of the handlers is invoked, it
* will be @name_vanished_handler. The reverse is also true.
*
- * This behavior makes it very simple to write applications that wants
- * to take action when a certain name exists, see <xref
- * linkend="gdbus-watching-names"/>. Basically, the application
- * should create object proxies in @name_appeared_handler and destroy
- * them again (if any) in @name_vanished_handler.
+ * This behavior makes it very simple to write applications that want
+ * to take action when a certain [name exists][gdbus-watching-names].
+ * Basically, the application should create object proxies in
+ * @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 *client;
- g_return_val_if_fail (bus_type != G_BUS_TYPE_NONE, 0);
g_return_val_if_fail (g_dbus_is_name (name), 0);
G_LOCK (lock);
client = g_new0 (Client, 1);
client->ref_count = 1;
- client->id = next_global_id++; /* 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;
client->name_vanished_handler = name_vanished_handler;
client->user_data = user_data;
client->user_data_free_func = user_data_free_func;
- client->main_context = g_main_context_get_thread_default ();
- if (client->main_context != NULL)
- g_main_context_ref (client->main_context);
+ client->main_context = g_main_context_ref_thread_default ();
if (map_id_to_client == NULL)
{
/**
* g_bus_watch_name_on_connection:
- * @connection: A #GDBusConnection that is not closed.
+ * @connection: A #GDBusConnection.
* @name: The name (well-known or unique) to watch.
* @flags: Flags from the #GBusNameWatcherFlags enumeration.
- * @name_appeared_handler: Handler to invoke when @name is known to exist or %NULL.
- * @name_vanished_handler: Handler to invoke when @name is known to not exist or %NULL.
+ * @name_appeared_handler: (nullable): Handler to invoke when @name is known to exist or %NULL.
+ * @name_vanished_handler: (nullable): Handler to invoke when @name is known to not exist or %NULL.
* @user_data: User data to pass to handlers.
- * @user_data_free_func: Function for freeing @user_data or %NULL.
+ * @user_data_free_func: (nullable): Function for freeing @user_data or %NULL.
*
* 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 = next_global_id++; /* 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;
client->name_vanished_handler = name_vanished_handler;
client->user_data = user_data;
client->user_data_free_func = user_data_free_func;
- client->main_context = g_main_context_get_thread_default ();
- if (client->main_context != NULL)
- g_main_context_ref (client->main_context);
+ client->main_context = g_main_context_ref_thread_default ();
if (map_id_to_client == NULL)
- {
- map_id_to_client = g_hash_table_new (g_direct_hash, g_direct_equal);
- }
+ map_id_to_client = g_hash_table_new (g_direct_hash, g_direct_equal);
+
g_hash_table_insert (map_id_to_client,
GUINT_TO_POINTER (client->id),
client);
return client->id;
}
+typedef struct {
+ GClosure *name_appeared_closure;
+ GClosure *name_vanished_closure;
+} WatchNameData;
+
+static WatchNameData *
+watch_name_data_new (GClosure *name_appeared_closure,
+ GClosure *name_vanished_closure)
+{
+ WatchNameData *data;
+
+ data = g_new0 (WatchNameData, 1);
+
+ if (name_appeared_closure != NULL)
+ {
+ data->name_appeared_closure = g_closure_ref (name_appeared_closure);
+ g_closure_sink (name_appeared_closure);
+ if (G_CLOSURE_NEEDS_MARSHAL (name_appeared_closure))
+ g_closure_set_marshal (name_appeared_closure, g_cclosure_marshal_generic);
+ }
+
+ if (name_vanished_closure != NULL)
+ {
+ data->name_vanished_closure = g_closure_ref (name_vanished_closure);
+ g_closure_sink (name_vanished_closure);
+ if (G_CLOSURE_NEEDS_MARSHAL (name_vanished_closure))
+ g_closure_set_marshal (name_vanished_closure, g_cclosure_marshal_generic);
+ }
+
+ return data;
+}
+
+static void
+watch_with_closures_on_name_appeared (GDBusConnection *connection,
+ const gchar *name,
+ const gchar *name_owner,
+ gpointer user_data)
+{
+ WatchNameData *data = user_data;
+ GValue params[3] = { G_VALUE_INIT, G_VALUE_INIT, G_VALUE_INIT };
+
+ g_value_init (¶ms[0], G_TYPE_DBUS_CONNECTION);
+ g_value_set_object (¶ms[0], connection);
+
+ g_value_init (¶ms[1], G_TYPE_STRING);
+ g_value_set_string (¶ms[1], name);
+
+ g_value_init (¶ms[2], G_TYPE_STRING);
+ g_value_set_string (¶ms[2], name_owner);
+
+ g_closure_invoke (data->name_appeared_closure, NULL, 3, params, NULL);
+
+ g_value_unset (params + 0);
+ g_value_unset (params + 1);
+ g_value_unset (params + 2);
+}
+
+static void
+watch_with_closures_on_name_vanished (GDBusConnection *connection,
+ const gchar *name,
+ gpointer user_data)
+{
+ WatchNameData *data = user_data;
+ GValue params[2] = { G_VALUE_INIT, G_VALUE_INIT };
+
+ g_value_init (¶ms[0], G_TYPE_DBUS_CONNECTION);
+ g_value_set_object (¶ms[0], connection);
+
+ g_value_init (¶ms[1], G_TYPE_STRING);
+ g_value_set_string (¶ms[1], name);
+
+ g_closure_invoke (data->name_vanished_closure, NULL, 2, params, NULL);
+
+ g_value_unset (params + 0);
+ g_value_unset (params + 1);
+}
+
+static void
+bus_watch_name_free_func (gpointer user_data)
+{
+ WatchNameData *data = user_data;
+
+ if (data->name_appeared_closure != NULL)
+ g_closure_unref (data->name_appeared_closure);
+
+ if (data->name_vanished_closure != NULL)
+ g_closure_unref (data->name_vanished_closure);
+
+ g_free (data);
+}
+
+/**
+ * g_bus_watch_name_with_closures: (rename-to g_bus_watch_name)
+ * @bus_type: The type of bus to watch a name on.
+ * @name: The name (well-known or unique) to watch.
+ * @flags: Flags from the #GBusNameWatcherFlags enumeration.
+ * @name_appeared_closure: (nullable): #GClosure to invoke when @name is known
+ * to exist or %NULL.
+ * @name_vanished_closure: (nullable): #GClosure to invoke when @name is known
+ * to not exist or %NULL.
+ *
+ * Version of g_bus_watch_name() using closures instead of callbacks for
+ * easier binding in other languages.
+ *
+ * Returns: An identifier (never 0) that can be used with
+ * g_bus_unwatch_name() to stop watching the name.
+ *
+ * Since: 2.26
+ */
+guint
+g_bus_watch_name_with_closures (GBusType bus_type,
+ const gchar *name,
+ GBusNameWatcherFlags flags,
+ GClosure *name_appeared_closure,
+ GClosure *name_vanished_closure)
+{
+ return g_bus_watch_name (bus_type,
+ name,
+ flags,
+ name_appeared_closure != NULL ? watch_with_closures_on_name_appeared : NULL,
+ name_vanished_closure != NULL ? watch_with_closures_on_name_vanished : NULL,
+ watch_name_data_new (name_appeared_closure, name_vanished_closure),
+ bus_watch_name_free_func);
+}
+
+/**
+ * g_bus_watch_name_on_connection_with_closures: (rename-to g_bus_watch_name_on_connection)
+ * @connection: A #GDBusConnection.
+ * @name: The name (well-known or unique) to watch.
+ * @flags: Flags from the #GBusNameWatcherFlags enumeration.
+ * @name_appeared_closure: (nullable): #GClosure to invoke when @name is known
+ * to exist or %NULL.
+ * @name_vanished_closure: (nullable): #GClosure to invoke when @name is known
+ * to not exist or %NULL.
+ *
+ * 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 can be used with
+ * g_bus_unwatch_name() to stop watching the name.
+ *
+ * Since: 2.26
+ */
+guint g_bus_watch_name_on_connection_with_closures (
+ GDBusConnection *connection,
+ const gchar *name,
+ GBusNameWatcherFlags flags,
+ GClosure *name_appeared_closure,
+ GClosure *name_vanished_closure)
+{
+ return g_bus_watch_name_on_connection (connection,
+ name,
+ flags,
+ name_appeared_closure != NULL ? watch_with_closures_on_name_appeared : NULL,
+ name_vanished_closure != NULL ? watch_with_closures_on_name_vanished : NULL,
+ watch_name_data_new (name_appeared_closure, name_vanished_closure),
+ bus_watch_name_free_func);
+}
+
/**
* g_bus_unwatch_name:
* @watcher_id: An identifier obtained from g_bus_watch_name()
*
* 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
client_unref (client);
}
}
-
-#define __G_DBUS_NAME_WATCHING_C__
-#include "gioaliasdef.c"