/* GDBus - GLib D-Bus Library
*
* Copyright (C) 2008-2010 Red Hat, Inc.
*
* 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.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* 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.
*
* Author: David Zeuthen <davidz@redhat.com>
*/
#include "config.h"
#include <stdlib.h>
#include "gdbusutils.h"
#include "gdbusnamewatching.h"
#include "gdbusproxywatching.h"
#include "gdbuserror.h"
#include "gdbusprivate.h"
#include "gdbusproxy.h"
#include "gdbusnamewatching.h"
#include "gcancellable.h"
#include "glibintl.h"
#include "gioalias.h"
/**
* SECTION:gdbusproxywatching
* @title: Watching Proxies
* @short_description: Simple API for watching proxies
* @include: gio/gio.h
*
* Convenience API for watching bus proxies.
*
* <example id="gdbus-watching-proxy"><title>Simple application watching a proxy</title><programlisting><xi:include xmlns:xi="http://www.w3.org/2001/XInclude" parse="text" href="../../../../gio/tests/gdbus-example-watch-proxy.c"><xi:fallback>FIXME: MISSING XINCLUDE CONTENT</xi:fallback></xi:include></programlisting></example>
*/
/* ---------------------------------------------------------------------------------------------------- */
G_LOCK_DEFINE_STATIC (lock);
static guint next_global_id = 1;
static GHashTable *map_id_to_client = NULL;
/* ---------------------------------------------------------------------------------------------------- */
typedef struct
{
guint id;
GBusProxyAppearedCallback proxy_appeared_handler;
GBusProxyVanishedCallback proxy_vanished_handler;
gpointer user_data;
GDestroyNotify user_data_free_func;
GMainContext *main_context;
gchar *name;
gchar *name_owner;
GDBusConnection *connection;
guint name_watcher_id;
GCancellable *cancellable;
gchar *object_path;
gchar *interface_name;
GType interface_type;
GDBusProxyFlags proxy_flags;
GDBusProxy *proxy;
gboolean initial_construction;
} Client;
static void
client_unref (Client *client)
{
/* ensure we're only called from g_bus_unwatch_proxy */
g_assert (client->name_watcher_id == 0);
g_free (client->name_owner);
if (client->connection != NULL)
g_object_unref (client->connection);
if (client->proxy != NULL)
g_object_unref (client->proxy);
g_free (client->name);
g_free (client->object_path);
g_free (client->interface_name);
if (client->main_context != NULL)
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
proxy_constructed_cb (GObject *source_object,
GAsyncResult *res,
gpointer user_data)
{
Client *client = user_data;
GDBusProxy *proxy;
GError *error;
error = NULL;
proxy = g_dbus_proxy_new_finish (res, &error);
if (proxy == NULL)
{
/* g_warning ("error while constructing proxy: %s", error->message); */
g_error_free (error);
/* handle initial construction, send out vanished if the name
* is there but we constructing a proxy fails
*/
if (client->initial_construction)
{
if (client->proxy_vanished_handler != NULL)
{
client->proxy_vanished_handler (client->connection,
client->name,
client->user_data);
}
client->initial_construction = FALSE;
}
}
else
{
g_assert (client->proxy == NULL);
g_assert (client->cancellable != NULL);
client->proxy = G_DBUS_PROXY (proxy);
g_object_unref (client->cancellable);
client->cancellable = NULL;
/* perform callback */
if (client->proxy_appeared_handler != NULL)
{
client->proxy_appeared_handler (client->connection,
client->name,
client->name_owner,
client->proxy,
client->user_data);
}
client->initial_construction = FALSE;
}
}
static void
on_name_appeared (GDBusConnection *connection,
const gchar *name,
const gchar *name_owner,
gpointer user_data)
{
Client *client = user_data;
//g_debug ("\n\nname appeared (owner `%s')", name_owner);
/* invariants */
g_assert (client->name_owner == NULL);
g_assert (client->connection == NULL);
g_assert (client->cancellable == NULL);
client->name_owner = g_strdup (name_owner);
client->connection = g_object_ref (connection);
client->cancellable = g_cancellable_new ();
g_dbus_proxy_new (client->connection,
client->interface_type,
client->proxy_flags,
NULL, /* GDBusInterfaceInfo */
client->name_owner,
client->object_path,
client->interface_name,
client->cancellable,
proxy_constructed_cb,
client);
}
static void
on_name_vanished (GDBusConnection *connection,
const gchar *name,
gpointer user_data)
{
Client *client = user_data;
/*g_debug ("\n\nname vanished");*/
g_free (client->name_owner);
if (client->connection != NULL)
g_object_unref (client->connection);
client->name_owner = NULL;
client->connection = NULL;
/* free the proxy if we have it */
if (client->proxy != NULL)
{
g_assert (client->cancellable == NULL);
g_object_unref (client->proxy);
client->proxy = NULL;
/* if we have the proxy, it means we last sent out a 'appeared'
* callback - so send out a 'vanished' callback
*/
if (client->proxy_vanished_handler != NULL)
{
client->proxy_vanished_handler (client->connection,
client->name,
client->user_data);
}
client->initial_construction = FALSE;
}
else
{
/* otherwise cancel construction of the proxy if applicable */
if (client->cancellable != NULL)
{
g_cancellable_cancel (client->cancellable);
g_object_unref (client->cancellable);
client->cancellable = NULL;
}
else
{
/* handle initial construction, send out vanished if
* the name isn't there
*/
if (client->initial_construction)
{
if (client->proxy_vanished_handler != NULL)
{
client->proxy_vanished_handler (client->connection,
client->name,
client->user_data);
}
client->initial_construction = FALSE;
}
}
}
}
/**
* g_bus_watch_proxy:
* @bus_type: The type of bus to watch a name on (can't be #G_BUS_TYPE_NONE).
* @name: The name (well-known or unique) to watch.
* @flags: Flags from the #GBusNameWatcherFlags enumeration.
* @object_path: The object path of the remote object to watch.
* @interface_name: The D-Bus interface name for the proxy.
* @interface_type: The #GType for the kind of proxy to create. This must be a #GDBusProxy derived type.
* @proxy_flags: Flags from #GDBusProxyFlags to use when constructing the proxy.
* @proxy_appeared_handler: Handler to invoke when @name is known to exist and the
* requested proxy is available.
* @proxy_vanished_handler: Handler to invoke when @name is known to not exist
* and the previously created proxy is no longer available.
* @user_data: User data to pass to handlers.
* @user_data_free_func: Function for freeing @user_data or %NULL.
*
* Starts watching a remote object at @object_path owned by @name on
* the bus specified by @bus_type. When the object is available, a
* #GDBusProxy (or derived class cf. @interface_type) instance is
* constructed for the @interface_name D-Bus interface and then
* @proxy_appeared_handler will be called when the proxy is ready and
* all properties have been loaded. When @name vanishes,
* @proxy_vanished_handler is called.
*
* This function makes it very simple to write applications that wants
* to watch a well-known remote object on a well-known name, see <xref
* linkend="gdbus-watching-proxy"/>. Basically, the application simply
* starts using the proxy when @proxy_appeared_handler is called and
* stops using it when @proxy_vanished_handler is called. 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.
*
* Applications typically use this function to watch the
* <quote>manager</quote> object of a well-known name. Upon acquiring
* a proxy for the manager object, applications typically construct
* additional proxies in response to the result of enumeration methods
* on the manager object.
*
* Many of the comments that apply to g_bus_watch_name() also apply
* here. For example, you are guaranteed that one of the handlers will
* be invoked (on the main thread) after calling this function and
* also that the two handlers alternate. When you are done watching the
* proxy, just call g_bus_unwatch_proxy().
*
* Returns: An identifier (never 0) that can be used with
* g_bus_unwatch_proxy() to stop watching the remote object.
*
* Since: 2.26
*/
guint
g_bus_watch_proxy (GBusType bus_type,
const gchar *name,
GBusNameWatcherFlags flags,
const gchar *object_path,
const gchar *interface_name,
GType interface_type,
GDBusProxyFlags proxy_flags,
GBusProxyAppearedCallback proxy_appeared_handler,
GBusProxyVanishedCallback proxy_vanished_handler,
gpointer user_data,
GDestroyNotify user_data_free_func)
{
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_return_val_if_fail (g_variant_is_object_path (object_path), 0);
g_return_val_if_fail (g_dbus_is_interface_name (interface_name), 0);
g_return_val_if_fail (g_type_is_a (interface_type, G_TYPE_DBUS_PROXY), 0);
G_LOCK (lock);
client = g_new0 (Client, 1);
client->id = next_global_id++; /* TODO: uh oh, handle overflow */
client->name = g_strdup (name);
client->proxy_appeared_handler = proxy_appeared_handler;
client->proxy_vanished_handler = proxy_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->name_watcher_id = g_bus_watch_name (bus_type,
name,
flags,
on_name_appeared,
on_name_vanished,
client,
NULL);
client->object_path = g_strdup (object_path);
client->interface_name = g_strdup (interface_name);
client->interface_type = interface_type;
client->proxy_flags = proxy_flags;
client->initial_construction = TRUE;
if (map_id_to_client == NULL)
{
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);
G_UNLOCK (lock);
return client->id;
}
/**
* g_bus_unwatch_proxy:
* @watcher_id: An identifier obtained from g_bus_watch_proxy()
*
* Stops watching proxy.
*
* Since: 2.26
*/
void
g_bus_unwatch_proxy (guint watcher_id)
{
Client *client;
g_return_if_fail (watcher_id > 0);
client = NULL;
G_LOCK (lock);
if (watcher_id == 0 ||
map_id_to_client == NULL ||
(client = g_hash_table_lookup (map_id_to_client, GUINT_TO_POINTER (watcher_id))) == NULL)
{
g_warning ("Invalid id %d passed to g_bus_unwatch_proxy()", watcher_id);
goto out;
}
g_warn_if_fail (g_hash_table_remove (map_id_to_client, GUINT_TO_POINTER (watcher_id)));
out:
G_UNLOCK (lock);
if (client != NULL)
{
g_bus_unwatch_name (client->name_watcher_id);
client->name_watcher_id = 0;
client_unref (client);
}
}
#define __G_DBUS_PROXY_WATCHING_C__
#include "gioaliasdef.c"