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glib/gio/gdbusnameowning.c
Simon McVittie 7c97e3d784 gdbus: Check signature of NameAcquired, NameLost 
Calling g_variant_get (parameters, "(&s)") when parameters has a
signature other than (s) is considered to be a programming error.
In practice the message bus (dbus-daemon or a reimplementation) should
always send the expected type, but be defensive.

(Modified by Philip Withnall to improve type check.)

Signed-off-by: Simon McVittie <smcv@collabora.com>
Signed-off-by: Philip Withnall <withnall@endlessm.com>

https://bugzilla.gnome.org/show_bug.cgi?id=784392
2017-08-07 17:31:31 +01:00

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/* 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 2.1 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
* 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, see <http://www.gnu.org/licenses/>.
*
* Author: David Zeuthen <davidz@redhat.com>
*/
#include "config.h"
#include <stdlib.h>
#include "gdbusutils.h"
#include "gdbusnameowning.h"
#include "gdbuserror.h"
#include "gdbusprivate.h"
#include "gdbusconnection.h"
#include "glibintl.h"
/**
* SECTION:gdbusnameowning
* @title: Owning Bus Names
* @short_description: Simple API for owning bus names
* @include: gio/gio.h
*
* Convenience API for owning bus names.
*
* A simple example for owning a name can be found in
* [gdbus-example-own-name.c](https://git.gnome.org/browse/glib/tree/gio/tests/gdbus-example-own-name.c)
*/
G_LOCK_DEFINE_STATIC (lock);
/* ---------------------------------------------------------------------------------------------------- */
typedef enum
{
PREVIOUS_CALL_NONE = 0,
PREVIOUS_CALL_ACQUIRED,
PREVIOUS_CALL_LOST,
} PreviousCall;
typedef struct
{
volatile gint ref_count;
guint id;
GBusNameOwnerFlags flags;
gchar *name;
GBusAcquiredCallback bus_acquired_handler;
GBusNameAcquiredCallback name_acquired_handler;
GBusNameLostCallback name_lost_handler;
gpointer user_data;
GDestroyNotify user_data_free_func;
GMainContext *main_context;
PreviousCall previous_call;
GDBusConnection *connection;
gulong disconnected_signal_handler_id;
guint name_acquired_subscription_id;
guint name_lost_subscription_id;
volatile gboolean cancelled; /* must hold lock when reading or modifying */
gboolean needs_release;
} Client;
static guint next_global_id = 1;
static GHashTable *map_id_to_client = NULL;
static Client *
client_ref (Client *client)
{
g_atomic_int_inc (&client->ref_count);
return client;
}
static void
client_unref (Client *client)
{
if (g_atomic_int_dec_and_test (&client->ref_count))
{
if (client->connection != NULL)
{
if (client->disconnected_signal_handler_id > 0)
g_signal_handler_disconnect (client->connection, client->disconnected_signal_handler_id);
if (client->name_acquired_subscription_id > 0)
g_dbus_connection_signal_unsubscribe (client->connection, client->name_acquired_subscription_id);
if (client->name_lost_subscription_id > 0)
g_dbus_connection_signal_unsubscribe (client->connection, client->name_lost_subscription_id);
g_object_unref (client->connection);
}
g_main_context_unref (client->main_context);
g_free (client->name);
if (client->user_data_free_func != NULL)
client->user_data_free_func (client->user_data);
g_free (client);
}
}
/* ---------------------------------------------------------------------------------------------------- */
typedef enum
{
CALL_TYPE_NAME_ACQUIRED,
CALL_TYPE_NAME_LOST
} CallType;
typedef struct
{
Client *client;
/* keep this separate because client->connection may
* be set to NULL after scheduling the call
*/
GDBusConnection *connection;
/* set to TRUE to call acquired */
CallType call_type;
} CallHandlerData;
static void
call_handler_data_free (CallHandlerData *data)
{
if (data->connection != NULL)
g_object_unref (data->connection);
client_unref (data->client);
g_free (data);
}
static void
actually_do_call (Client *client, GDBusConnection *connection, CallType call_type)
{
switch (call_type)
{
case CALL_TYPE_NAME_ACQUIRED:
if (client->name_acquired_handler != NULL)
{
client->name_acquired_handler (connection,
client->name,
client->user_data);
}
break;
case CALL_TYPE_NAME_LOST:
if (client->name_lost_handler != NULL)
{
client->name_lost_handler (connection,
client->name,
client->user_data);
}
break;
default:
g_assert_not_reached ();
break;
}
}
static gboolean
call_in_idle_cb (gpointer _data)
{
CallHandlerData *data = _data;
actually_do_call (data->client, data->connection, data->call_type);
return FALSE;
}
static void
schedule_call_in_idle (Client *client, CallType call_type)
{
CallHandlerData *data;
GSource *idle_source;
data = g_new0 (CallHandlerData, 1);
data->client = client_ref (client);
data->connection = client->connection != NULL ? g_object_ref (client->connection) : NULL;
data->call_type = call_type;
idle_source = g_idle_source_new ();
g_source_set_priority (idle_source, G_PRIORITY_HIGH);
g_source_set_callback (idle_source,
call_in_idle_cb,
data,
(GDestroyNotify) call_handler_data_free);
g_source_set_name (idle_source, "[gio, gdbusnameowning.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 */
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, call_type);
g_main_context_unref (current_context);
}
static void
call_acquired_handler (Client *client)
{
G_LOCK (lock);
if (client->previous_call != PREVIOUS_CALL_ACQUIRED)
{
client->previous_call = PREVIOUS_CALL_ACQUIRED;
if (!client->cancelled)
{
G_UNLOCK (lock);
do_call (client, CALL_TYPE_NAME_ACQUIRED);
goto out;
}
}
G_UNLOCK (lock);
out:
;
}
static void
call_lost_handler (Client *client)
{
G_LOCK (lock);
if (client->previous_call != PREVIOUS_CALL_LOST)
{
client->previous_call = PREVIOUS_CALL_LOST;
if (!client->cancelled)
{
G_UNLOCK (lock);
do_call (client, CALL_TYPE_NAME_LOST);
goto out;
}
}
G_UNLOCK (lock);
out:
;
}
/* ---------------------------------------------------------------------------------------------------- */
static void
on_name_lost_or_acquired (GDBusConnection *connection,
const gchar *sender_name,
const gchar *object_path,
const gchar *interface_name,
const gchar *signal_name,
GVariant *parameters,
gpointer user_data)
{
Client *client = user_data;
const gchar *name;
if (g_strcmp0 (object_path, "/org/freedesktop/DBus") != 0 ||
g_strcmp0 (interface_name, "org.freedesktop.DBus") != 0 ||
g_strcmp0 (sender_name, "org.freedesktop.DBus") != 0)
goto out;
if (!g_variant_is_of_type (parameters, G_VARIANT_TYPE ("(s)")))
{
g_warning ("%s signal had unexpected signature %s", signal_name,
g_variant_get_type_string (parameters));
goto out;
}
if (g_strcmp0 (signal_name, "NameLost") == 0)
{
g_variant_get (parameters, "(&s)", &name);
if (g_strcmp0 (name, client->name) == 0)
{
call_lost_handler (client);
}
}
else if (g_strcmp0 (signal_name, "NameAcquired") == 0)
{
g_variant_get (parameters, "(&s)", &name);
if (g_strcmp0 (name, client->name) == 0)
{
call_acquired_handler (client);
}
}
out:
;
}
/* ---------------------------------------------------------------------------------------------------- */
static void
request_name_cb (GObject *source_object,
GAsyncResult *res,
gpointer user_data)
{
Client *client = user_data;
GVariant *result;
guint32 request_name_reply;
gboolean subscribe;
request_name_reply = 0;
result = NULL;
/* don't use client->connection - it may be NULL already */
result = g_dbus_connection_call_finish (G_DBUS_CONNECTION (source_object),
res,
NULL);
if (result != NULL)
{
g_variant_get (result, "(u)", &request_name_reply);
g_variant_unref (result);
}
subscribe = FALSE;
switch (request_name_reply)
{
case 1: /* DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER */
/* We got the name - now listen for NameLost and NameAcquired */
call_acquired_handler (client);
subscribe = TRUE;
client->needs_release = TRUE;
break;
case 2: /* DBUS_REQUEST_NAME_REPLY_IN_QUEUE */
/* Waiting in line - listen for NameLost and NameAcquired */
call_lost_handler (client);
subscribe = TRUE;
client->needs_release = TRUE;
break;
default:
/* assume we couldn't get the name - explicit fallthrough */
case 3: /* DBUS_REQUEST_NAME_REPLY_EXISTS */
case 4: /* DBUS_REQUEST_NAME_REPLY_ALREADY_OWNER */
/* Some other part of the process is already owning the name */
call_lost_handler (client);
break;
}
if (subscribe)
{
GDBusConnection *connection = NULL;
/* if cancelled, there is no point in subscribing to signals - if not, make sure
* we use a known good Connection object since it may be set to NULL at any point
* after being cancelled
*/
G_LOCK (lock);
if (!client->cancelled)
connection = g_object_ref (client->connection);
G_UNLOCK (lock);
/* start listening to NameLost and NameAcquired messages */
if (connection != NULL)
{
client->name_lost_subscription_id =
g_dbus_connection_signal_subscribe (connection,
"org.freedesktop.DBus",
"org.freedesktop.DBus",
"NameLost",
"/org/freedesktop/DBus",
client->name,
G_DBUS_SIGNAL_FLAGS_NONE,
on_name_lost_or_acquired,
client,
NULL);
client->name_acquired_subscription_id =
g_dbus_connection_signal_subscribe (connection,
"org.freedesktop.DBus",
"org.freedesktop.DBus",
"NameAcquired",
"/org/freedesktop/DBus",
client->name,
G_DBUS_SIGNAL_FLAGS_NONE,
on_name_lost_or_acquired,
client,
NULL);
g_object_unref (connection);
}
}
client_unref (client);
}
/* ---------------------------------------------------------------------------------------------------- */
static void
on_connection_disconnected (GDBusConnection *connection,
gboolean remote_peer_vanished,
GError *error,
gpointer user_data)
{
Client *client = user_data;
if (client->disconnected_signal_handler_id > 0)
g_signal_handler_disconnect (client->connection, client->disconnected_signal_handler_id);
if (client->name_acquired_subscription_id > 0)
g_dbus_connection_signal_unsubscribe (client->connection, client->name_acquired_subscription_id);
if (client->name_lost_subscription_id > 0)
g_dbus_connection_signal_unsubscribe (client->connection, client->name_lost_subscription_id);
g_object_unref (client->connection);
client->disconnected_signal_handler_id = 0;
client->name_acquired_subscription_id = 0;
client->name_lost_subscription_id = 0;
client->connection = NULL;
call_lost_handler (client);
}
/* ---------------------------------------------------------------------------------------------------- */
static void
has_connection (Client *client)
{
/* listen for disconnection */
client->disconnected_signal_handler_id = g_signal_connect (client->connection,
"closed",
G_CALLBACK (on_connection_disconnected),
client);
/* attempt to acquire the name */
g_dbus_connection_call (client->connection,
"org.freedesktop.DBus", /* bus name */
"/org/freedesktop/DBus", /* object path */
"org.freedesktop.DBus", /* interface name */
"RequestName", /* method name */
g_variant_new ("(su)",
client->name,
client->flags),
G_VARIANT_TYPE ("(u)"),
G_DBUS_CALL_FLAGS_NONE,
-1,
NULL,
(GAsyncReadyCallback) request_name_cb,
client_ref (client));
}
static void
connection_get_cb (GObject *source_object,
GAsyncResult *res,
gpointer user_data)
{
Client *client = user_data;
/* must not do anything if already cancelled */
G_LOCK (lock);
if (client->cancelled)
{
G_UNLOCK (lock);
goto out;
}
G_UNLOCK (lock);
client->connection = g_bus_get_finish (res, NULL);
if (client->connection == NULL)
{
call_lost_handler (client);
goto out;
}
/* No need to schedule this in idle as we're already in the thread
* that the user called g_bus_own_name() from. This is because
* g_bus_get() guarantees that.
*
* Also, we need to ensure that the handler is invoked *before*
* we call RequestName(). Otherwise there is a race.
*/
if (client->bus_acquired_handler != NULL)
{
client->bus_acquired_handler (client->connection,
client->name,
client->user_data);
}
has_connection (client);
out:
client_unref (client);
}
/* ---------------------------------------------------------------------------------------------------- */
/**
* g_bus_own_name_on_connection:
* @connection: a #GDBusConnection
* @name: the well-known name to own
* @flags: a set of flags from the #GBusNameOwnerFlags enumeration
* @name_acquired_handler: (nullable): handler to invoke when @name is acquired or %NULL
* @name_lost_handler: (nullable): handler to invoke when @name is lost or %NULL
* @user_data: user data to pass to handlers
* @user_data_free_func: (nullable): function for freeing @user_data or %NULL
*
* Like g_bus_own_name() but takes a #GDBusConnection instead of a
* #GBusType.
*
* Returns: an identifier (never 0) that an be used with
* g_bus_unown_name() to stop owning the name
*
* Since: 2.26
*/
guint
g_bus_own_name_on_connection (GDBusConnection *connection,
const gchar *name,
GBusNameOwnerFlags flags,
GBusNameAcquiredCallback name_acquired_handler,
GBusNameLostCallback name_lost_handler,
gpointer user_data,
GDestroyNotify user_data_free_func)
{
Client *client;
g_return_val_if_fail (G_IS_DBUS_CONNECTION (connection), 0);
g_return_val_if_fail (g_dbus_is_name (name) && !g_dbus_is_unique_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->name = g_strdup (name);
client->flags = flags;
client->name_acquired_handler = name_acquired_handler;
client->name_lost_handler = name_lost_handler;
client->user_data = user_data;
client->user_data_free_func = user_data_free_func;
client->main_context = g_main_context_ref_thread_default ();
client->connection = g_object_ref (connection);
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);
has_connection (client);
return client->id;
}
/**
* g_bus_own_name:
* @bus_type: the type of bus to own a name on
* @name: the well-known name to own
* @flags: a set of flags from the #GBusNameOwnerFlags enumeration
* @bus_acquired_handler: (nullable): handler to invoke when connected to the bus of type @bus_type or %NULL
* @name_acquired_handler: (nullable): handler to invoke when @name is acquired or %NULL
* @name_lost_handler: (nullable): handler to invoke when @name is lost or %NULL
* @user_data: user data to pass to handlers
* @user_data_free_func: (nullable): function for freeing @user_data or %NULL
*
* Starts acquiring @name on the bus specified by @bus_type and calls
* @name_acquired_handler and @name_lost_handler when the name is
* acquired respectively lost. 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 @name_acquired_handler and @name_lost_handler
* callbacks will be invoked after calling this function - there are three
* possible cases:
*
* - @name_lost_handler with a %NULL connection (if a connection to the bus
* can't be made).
*
* - @bus_acquired_handler then @name_lost_handler (if the name can't be
* obtained)
*
* - @bus_acquired_handler then @name_acquired_handler (if the name was
* obtained).
*
* When you are done owning the name, just call g_bus_unown_name()
* with the owner id this function returns.
*
* If the name is acquired or lost (for example another application
* could acquire the name if you allow replacement or the application
* currently owning the name exits), the handlers are also invoked.
* If the #GDBusConnection that is used for attempting to own the name
* closes, then @name_lost_handler is invoked since it is no longer
* possible for other processes to access the process.
*
* You cannot use g_bus_own_name() several times for the same name (unless
* interleaved with calls to g_bus_unown_name()) - only the first call
* will work.
*
* Another guarantee is that invocations of @name_acquired_handler
* and @name_lost_handler are guaranteed to alternate; that
* is, if @name_acquired_handler is invoked then you are
* guaranteed that the next time one of the handlers is invoked, it
* will be @name_lost_handler. The reverse is also true.
*
* If you plan on exporting objects (using e.g.
* g_dbus_connection_register_object()), note that it is generally too late
* to export the objects in @name_acquired_handler. Instead, you can do this
* in @bus_acquired_handler since you are guaranteed that this will run
* before @name is requested from the bus.
*
* This behavior makes it very simple to write applications that wants
* to [own names][gdbus-owning-names] and export objects.
* Simply register objects to be exported in @bus_acquired_handler and
* unregister the objects (if any) in @name_lost_handler.
*
* Returns: an identifier (never 0) that an be used with
* g_bus_unown_name() to stop owning the name.
*
* Since: 2.26
*/
guint
g_bus_own_name (GBusType bus_type,
const gchar *name,
GBusNameOwnerFlags flags,
GBusAcquiredCallback bus_acquired_handler,
GBusNameAcquiredCallback name_acquired_handler,
GBusNameLostCallback name_lost_handler,
gpointer user_data,
GDestroyNotify user_data_free_func)
{
Client *client;
g_return_val_if_fail (g_dbus_is_name (name) && !g_dbus_is_unique_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->name = g_strdup (name);
client->flags = flags;
client->bus_acquired_handler = bus_acquired_handler;
client->name_acquired_handler = name_acquired_handler;
client->name_lost_handler = name_lost_handler;
client->user_data = user_data;
client->user_data_free_func = user_data_free_func;
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);
}
g_hash_table_insert (map_id_to_client,
GUINT_TO_POINTER (client->id),
client);
g_bus_get (bus_type,
NULL,
connection_get_cb,
client_ref (client));
G_UNLOCK (lock);
return client->id;
}
typedef struct {
GClosure *bus_acquired_closure;
GClosure *name_acquired_closure;
GClosure *name_lost_closure;
} OwnNameData;
static OwnNameData *
own_name_data_new (GClosure *bus_acquired_closure,
GClosure *name_acquired_closure,
GClosure *name_lost_closure)
{
OwnNameData *data;
data = g_new0 (OwnNameData, 1);
if (bus_acquired_closure != NULL)
{
data->bus_acquired_closure = g_closure_ref (bus_acquired_closure);
g_closure_sink (bus_acquired_closure);
if (G_CLOSURE_NEEDS_MARSHAL (bus_acquired_closure))
g_closure_set_marshal (bus_acquired_closure, g_cclosure_marshal_generic);
}
if (name_acquired_closure != NULL)
{
data->name_acquired_closure = g_closure_ref (name_acquired_closure);
g_closure_sink (name_acquired_closure);
if (G_CLOSURE_NEEDS_MARSHAL (name_acquired_closure))
g_closure_set_marshal (name_acquired_closure, g_cclosure_marshal_generic);
}
if (name_lost_closure != NULL)
{
data->name_lost_closure = g_closure_ref (name_lost_closure);
g_closure_sink (name_lost_closure);
if (G_CLOSURE_NEEDS_MARSHAL (name_lost_closure))
g_closure_set_marshal (name_lost_closure, g_cclosure_marshal_generic);
}
return data;
}
static void
own_with_closures_on_bus_acquired (GDBusConnection *connection,
const gchar *name,
gpointer user_data)
{
OwnNameData *data = user_data;
GValue params[2] = { G_VALUE_INIT, G_VALUE_INIT };
g_value_init (&params[0], G_TYPE_DBUS_CONNECTION);
g_value_set_object (&params[0], connection);
g_value_init (&params[1], G_TYPE_STRING);
g_value_set_string (&params[1], name);
g_closure_invoke (data->bus_acquired_closure, NULL, 2, params, NULL);
g_value_unset (params + 0);
g_value_unset (params + 1);
}
static void
own_with_closures_on_name_acquired (GDBusConnection *connection,
const gchar *name,
gpointer user_data)
{
OwnNameData *data = user_data;
GValue params[2] = { G_VALUE_INIT, G_VALUE_INIT };
g_value_init (&params[0], G_TYPE_DBUS_CONNECTION);
g_value_set_object (&params[0], connection);
g_value_init (&params[1], G_TYPE_STRING);
g_value_set_string (&params[1], name);
g_closure_invoke (data->name_acquired_closure, NULL, 2, params, NULL);
g_value_unset (params + 0);
g_value_unset (params + 1);
}
static void
own_with_closures_on_name_lost (GDBusConnection *connection,
const gchar *name,
gpointer user_data)
{
OwnNameData *data = user_data;
GValue params[2] = { G_VALUE_INIT, G_VALUE_INIT };
g_value_init (&params[0], G_TYPE_DBUS_CONNECTION);
g_value_set_object (&params[0], connection);
g_value_init (&params[1], G_TYPE_STRING);
g_value_set_string (&params[1], name);
g_closure_invoke (data->name_lost_closure, NULL, 2, params, NULL);
g_value_unset (params + 0);
g_value_unset (params + 1);
}
static void
bus_own_name_free_func (gpointer user_data)
{
OwnNameData *data = user_data;
if (data->bus_acquired_closure != NULL)
g_closure_unref (data->bus_acquired_closure);
if (data->name_acquired_closure != NULL)
g_closure_unref (data->name_acquired_closure);
if (data->name_lost_closure != NULL)
g_closure_unref (data->name_lost_closure);
g_free (data);
}
/**
* g_bus_own_name_with_closures: (rename-to g_bus_own_name)
* @bus_type: the type of bus to own a name on
* @name: the well-known name to own
* @flags: a set of flags from the #GBusNameOwnerFlags enumeration
* @bus_acquired_closure: (nullable): #GClosure to invoke when connected to
* the bus of type @bus_type or %NULL
* @name_acquired_closure: (nullable): #GClosure to invoke when @name is
* acquired or %NULL
* @name_lost_closure: (nullable): #GClosure to invoke when @name is lost or
* %NULL
*
* Version of g_bus_own_name() using closures instead of callbacks for
* easier binding in other languages.
*
* Returns: an identifier (never 0) that an be used with
* g_bus_unown_name() to stop owning the name.
*
* Since: 2.26
*/
guint
g_bus_own_name_with_closures (GBusType bus_type,
const gchar *name,
GBusNameOwnerFlags flags,
GClosure *bus_acquired_closure,
GClosure *name_acquired_closure,
GClosure *name_lost_closure)
{
return g_bus_own_name (bus_type,
name,
flags,
bus_acquired_closure != NULL ? own_with_closures_on_bus_acquired : NULL,
name_acquired_closure != NULL ? own_with_closures_on_name_acquired : NULL,
name_lost_closure != NULL ? own_with_closures_on_name_lost : NULL,
own_name_data_new (bus_acquired_closure,
name_acquired_closure,
name_lost_closure),
bus_own_name_free_func);
}
/**
* g_bus_own_name_on_connection_with_closures: (rename-to g_bus_own_name_on_connection)
* @connection: a #GDBusConnection
* @name: the well-known name to own
* @flags: a set of flags from the #GBusNameOwnerFlags enumeration
* @name_acquired_closure: (nullable): #GClosure to invoke when @name is
* acquired or %NULL
* @name_lost_closure: (nullable): #GClosure to invoke when @name is lost
* or %NULL
*
* Version of g_bus_own_name_on_connection() using closures instead of
* callbacks for easier binding in other languages.
*
* Returns: an identifier (never 0) that an be used with
* g_bus_unown_name() to stop owning the name.
*
* Since: 2.26
*/
guint
g_bus_own_name_on_connection_with_closures (GDBusConnection *connection,
const gchar *name,
GBusNameOwnerFlags flags,
GClosure *name_acquired_closure,
GClosure *name_lost_closure)
{
return g_bus_own_name_on_connection (connection,
name,
flags,
name_acquired_closure != NULL ? own_with_closures_on_name_acquired : NULL,
name_lost_closure != NULL ? own_with_closures_on_name_lost : NULL,
own_name_data_new (NULL,
name_acquired_closure,
name_lost_closure),
bus_own_name_free_func);
}
/**
* g_bus_unown_name:
* @owner_id: an identifier obtained from g_bus_own_name()
*
* Stops owning a name.
*
* Since: 2.26
*/
void
g_bus_unown_name (guint owner_id)
{
Client *client;
g_return_if_fail (owner_id > 0);
client = NULL;
G_LOCK (lock);
if (owner_id == 0 || map_id_to_client == NULL ||
(client = g_hash_table_lookup (map_id_to_client, GUINT_TO_POINTER (owner_id))) == NULL)
{
g_warning ("Invalid id %d passed to g_bus_unown_name()", owner_id);
goto out;
}
client->cancelled = TRUE;
g_warn_if_fail (g_hash_table_remove (map_id_to_client, GUINT_TO_POINTER (owner_id)));
out:
G_UNLOCK (lock);
/* do callback without holding lock */
if (client != NULL)
{
/* Release the name if needed */
if (client->needs_release &&
client->connection != NULL &&
!g_dbus_connection_is_closed (client->connection))
{
GVariant *result;
GError *error;
guint32 release_name_reply;
/* TODO: it kinda sucks having to do a sync call to release the name - but if
* we don't, then a subsequent grab of the name will make the bus daemon return
* IN_QUEUE which will trigger name_lost().
*
* I believe this is a bug in the bus daemon.
*/
error = NULL;
result = g_dbus_connection_call_sync (client->connection,
"org.freedesktop.DBus", /* bus name */
"/org/freedesktop/DBus", /* object path */
"org.freedesktop.DBus", /* interface name */
"ReleaseName", /* method name */
g_variant_new ("(s)", client->name),
G_VARIANT_TYPE ("(u)"),
G_DBUS_CALL_FLAGS_NONE,
-1,
NULL,
&error);
if (result == NULL)
{
g_warning ("Error releasing name %s: %s", client->name, error->message);
g_error_free (error);
}
else
{
g_variant_get (result, "(u)", &release_name_reply);
if (release_name_reply != 1 /* DBUS_RELEASE_NAME_REPLY_RELEASED */)
{
g_warning ("Unexpected reply %d when releasing name %s", release_name_reply, client->name);
}
g_variant_unref (result);
}
}
if (client->disconnected_signal_handler_id > 0)
g_signal_handler_disconnect (client->connection, client->disconnected_signal_handler_id);
if (client->name_acquired_subscription_id > 0)
g_dbus_connection_signal_unsubscribe (client->connection, client->name_acquired_subscription_id);
if (client->name_lost_subscription_id > 0)
g_dbus_connection_signal_unsubscribe (client->connection, client->name_lost_subscription_id);
client->disconnected_signal_handler_id = 0;
client->name_acquired_subscription_id = 0;
client->name_lost_subscription_id = 0;
if (client->connection != NULL)
{
g_object_unref (client->connection);
client->connection = NULL;
}
client_unref (client);
}
}
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