/**
* Checks whether a certain name has an owner.
*
* @param connection the connection
* @param name the name
* @param error location to store any errors
* @returns #TRUE if the name exists, #FALSE if not or on error
*/
dbus_bool_t
dbus_bus_name_has_owner (DBusConnection *connection,
const char *name,
DBusError *error)
{
DBusMessage *message, *reply;
dbus_bool_t exists;
_dbus_return_val_if_fail (connection != NULL, FALSE);
_dbus_return_val_if_fail (name != NULL, FALSE);
_dbus_return_val_if_fail (_dbus_check_is_valid_bus_name (name), FALSE);
_dbus_return_val_if_error_is_set (error, FALSE);
message = dbus_message_new_method_call (DBUS_SERVICE_DBUS,
DBUS_PATH_DBUS,
DBUS_INTERFACE_DBUS,
"NameHasOwner");
if (message == NULL)
{
_DBUS_SET_OOM (error);
return FALSE;
}
if (!dbus_message_append_args (message,
DBUS_TYPE_STRING, &name,
DBUS_TYPE_INVALID))
{
dbus_message_unref (message);
_DBUS_SET_OOM (error);
return FALSE;
}
reply = dbus_connection_send_with_reply_and_block (connection, message, -1, error);
dbus_message_unref (message);
if (reply == NULL)
{
_DBUS_ASSERT_ERROR_IS_SET (error);
return FALSE;
}
if (!dbus_message_get_args (reply, error,
DBUS_TYPE_BOOLEAN, &exists,
DBUS_TYPE_INVALID))
{
_DBUS_ASSERT_ERROR_IS_SET (error);
dbus_message_unref (reply);
return FALSE;
}
dbus_message_unref (reply);
return exists;
}
/**
* Reads arguments from a message iterator given a variable argument
* list. Only arguments of basic type and arrays of fixed-length
* basic type may be read with this function. See
* dbus_message_get_args() for more details.
*
* @param iter the message iterator
* @param error error to be filled in on failure
* @param first_arg_type the first argument type
* @param ... location for first argument value, then list of type-location pairs
* @returns #FALSE if the error was set
*/
static dbus_bool_t
dbus_message_iter_get_args (DBusMessageIter *iter,
DBusError *error,
int first_arg_type,
...)
{
dbus_bool_t retval;
va_list var_args;
_dbus_return_val_if_fail (iter != NULL, FALSE);
_dbus_return_val_if_error_is_set (error, FALSE);
va_start (var_args, first_arg_type);
retval = _dbus_message_iter_get_args_valist (iter, error, first_arg_type, var_args);
va_end (var_args);
return retval;
}
/**
* Listens for new connections on the given address. If there are
* multiple semicolon-separated address entries in the address, tries
* each one and listens on the first one that works.
*
* Returns #NULL and sets error if listening fails for any reason.
* Otherwise returns a new #DBusServer.
* dbus_server_set_new_connection_function(),
* dbus_server_set_watch_functions(), and
* dbus_server_set_timeout_functions() should be called immediately to
* render the server fully functional.
*
* To free the server, applications must call first
* dbus_server_disconnect() and then dbus_server_unref().
*
* @param address the address of this server.
* @param error location to store reason for failure.
* @returns a new #DBusServer, or #NULL on failure.
*
*/
DBusServer*
dbus_server_listen (const char *address,
DBusError *error)
{
DBusServer *server;
DBusAddressEntry **entries;
int len, i;
DBusError first_connect_error = DBUS_ERROR_INIT;
dbus_bool_t handled_once;
_dbus_return_val_if_fail (address != NULL, NULL);
_dbus_return_val_if_error_is_set (error, NULL);
if (!dbus_parse_address (address, &entries, &len, error))
return NULL;
server = NULL;
handled_once = FALSE;
for (i = 0; i < len; i++)
{
int j;
for (j = 0; j < (int) _DBUS_N_ELEMENTS (listen_funcs); ++j)
{
DBusServerListenResult result;
DBusError tmp_error = DBUS_ERROR_INIT;
result = (* listen_funcs[j].func) (entries[i],
&server,
&tmp_error);
if (result == DBUS_SERVER_LISTEN_OK)
{
_dbus_assert (server != NULL);
_DBUS_ASSERT_ERROR_IS_CLEAR (&tmp_error);
handled_once = TRUE;
goto out;
}
else if (result == DBUS_SERVER_LISTEN_ADDRESS_ALREADY_USED)
{
_dbus_assert (server == NULL);
dbus_set_error (error,
DBUS_ERROR_ADDRESS_IN_USE,
"Address '%s' already used",
dbus_address_entry_get_method (entries[0]));
handled_once = TRUE;
goto out;
}
else if (result == DBUS_SERVER_LISTEN_BAD_ADDRESS)
{
_dbus_assert (server == NULL);
_DBUS_ASSERT_ERROR_IS_SET (&tmp_error);
dbus_move_error (&tmp_error, error);
handled_once = TRUE;
goto out;
}
else if (result == DBUS_SERVER_LISTEN_NOT_HANDLED)
{
_dbus_assert (server == NULL);
_DBUS_ASSERT_ERROR_IS_CLEAR (&tmp_error);
/* keep trying addresses */
}
else if (result == DBUS_SERVER_LISTEN_DID_NOT_CONNECT)
{
_dbus_assert (server == NULL);
_DBUS_ASSERT_ERROR_IS_SET (&tmp_error);
if (!dbus_error_is_set (&first_connect_error))
dbus_move_error (&tmp_error, &first_connect_error);
else
dbus_error_free (&tmp_error);
handled_once = TRUE;
/* keep trying addresses */
}
}
_dbus_assert (server == NULL);
_DBUS_ASSERT_ERROR_IS_CLEAR (error);
}
out:
if (!handled_once)
{
_DBUS_ASSERT_ERROR_IS_CLEAR (error);
if (len > 0)
dbus_set_error (error,
DBUS_ERROR_BAD_ADDRESS,
"Unknown address type '%s'",
dbus_address_entry_get_method (entries[0]));
else
dbus_set_error (error,
DBUS_ERROR_BAD_ADDRESS,
"Empty address '%s'",
address);
}
dbus_address_entries_free (entries);
if (server == NULL)
{
_dbus_assert (error == NULL || dbus_error_is_set (&first_connect_error) ||
dbus_error_is_set (error));
if (error && dbus_error_is_set (error))
{
/* already set the error */
}
else
{
/* didn't set the error but either error should be
* NULL or first_connect_error should be set.
*/
_dbus_assert (error == NULL || dbus_error_is_set (&first_connect_error));
dbus_move_error (&first_connect_error, error);
}
_DBUS_ASSERT_ERROR_IS_CLEAR (&first_connect_error); /* be sure we freed it */
_DBUS_ASSERT_ERROR_IS_SET (error);
return NULL;
}
else
{
_DBUS_ASSERT_ERROR_IS_CLEAR (error);
return server;
}
}
/**
* Asks the bus to assign the given name to this connection by invoking
* the RequestName method on the bus. This method is fully documented
* in the D-BUS specification. For quick reference, the flags and
* result codes are discussed here, but the specification is the
* canonical version of this information.
*
* The #DBUS_NAME_FLAG_PROHIBIT_REPLACEMENT flag indicates that
* if the name is successfully requested, other applications
* will not be able to take over the name. i.e. the name's
* owner (the application calling this function) must let go of
* the name, it will not lose it involuntarily.
*
* The #DBUS_NAME_FLAG_REPLACE_EXISTING flag indicates that the caller
* would like to take over the name from the current owner.
* If the current name owner used #DBUS_NAME_FLAG_PROHIBIT_REPLACEMENT
* then this flag indicates that the caller would like to be placed
* in the queue to own the name when the current owner lets go.
*
* If no flags are given, an application will receive the requested
* name only if the name is currently unowned; and it will give
* up the name if another application asks to take it over using
* #DBUS_NAME_FLAG_REPLACE_EXISTING.
*
* This function returns a result code. The possible result codes
* are as follows.
*
* #DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER means that the name had no
* existing owner, and the caller is now the primary owner; or that
* the name had an owner, and the caller specified
* #DBUS_NAME_FLAG_REPLACE_EXISTING, and the current owner did not
* specify #DBUS_NAME_FLAG_PROHIBIT_REPLACEMENT.
*
* #DBUS_REQUEST_NAME_REPLY_IN_QUEUE happens only if the current owner
* specified #DBUS_NAME_FLAG_PROHIBIT_REPLACEMENT and the caller specified
* #DBUS_NAME_FLAG_REPLACE_EXISTING. In this case the caller ends up in
* a queue to own the name after the current owner gives it up.
*
* #DBUS_REQUEST_NAME_REPLY_EXISTS happens if the name has an owner
* #already and DBUS_NAME_FLAG_REPLACE_EXISTING was not specified.
*
* #DBUS_REQUEST_NAME_REPLY_ALREADY_OWNER happens if an application
* requests a name it already owns.
*
* When a service represents an application, say "text editor," then
* it should specify #DBUS_NAME_FLAG_PROHIBIT_REPLACEMENT if it wants
* the first editor started to be the user's editor vs. the last one
* started. Then any editor that can be the user's editor should
* specify #DBUS_NAME_FLAG_REPLACE_EXISTING to either take over
* (last-started-wins) or be queued up (first-started-wins) according
* to whether #DBUS_NAME_FLAG_PROHIBIT_REPLACEMENT was given.
*
* @todo this all seems sort of broken. Shouldn't the flags be a property
* of the name, not the app requesting the name? What are the use-cases
* other than the "text editor" thing and how are we supporting them?
*
* @param connection the connection
* @param name the name to request
* @param flags flags
* @param error location to store the error
* @returns a result code, -1 if error is set
*/
int
dbus_bus_request_name (DBusConnection *connection,
const char *name,
unsigned int flags,
DBusError *error)
{
DBusMessage *message, *reply;
dbus_uint32_t result;
_dbus_return_val_if_fail (connection != NULL, 0);
_dbus_return_val_if_fail (name != NULL, 0);
_dbus_return_val_if_fail (_dbus_check_is_valid_bus_name (name), 0);
_dbus_return_val_if_error_is_set (error, 0);
message = dbus_message_new_method_call (DBUS_SERVICE_DBUS,
DBUS_PATH_DBUS,
DBUS_INTERFACE_DBUS,
"RequestName");
if (message == NULL)
{
_DBUS_SET_OOM (error);
return -1;
}
if (!dbus_message_append_args (message,
DBUS_TYPE_STRING, &name,
DBUS_TYPE_UINT32, &flags,
DBUS_TYPE_INVALID))
{
dbus_message_unref (message);
_DBUS_SET_OOM (error);
return -1;
}
reply = dbus_connection_send_with_reply_and_block (connection, message, -1,
error);
dbus_message_unref (message);
if (reply == NULL)
{
_DBUS_ASSERT_ERROR_IS_SET (error);
return -1;
}
if (dbus_set_error_from_message (error, reply))
{
_DBUS_ASSERT_ERROR_IS_SET (error);
dbus_message_unref (reply);
return -1;
}
if (!dbus_message_get_args (reply, error,
DBUS_TYPE_UINT32, &result,
DBUS_TYPE_INVALID))
{
_DBUS_ASSERT_ERROR_IS_SET (error);
dbus_message_unref (reply);
return -1;
}
dbus_message_unref (reply);
return result;
}
/**
* Asks the bus to return the uid of the named
* connection.
*
* @param connection the connection
* @param name a name owned by the connection
* @param error location to store the error
* @returns a result code, -1 if error is set
*/
unsigned long
dbus_bus_get_unix_user (DBusConnection *connection,
const char *name,
DBusError *error)
{
DBusMessage *message, *reply;
dbus_uint32_t uid;
_dbus_return_val_if_fail (connection != NULL, DBUS_UID_UNSET);
_dbus_return_val_if_fail (name != NULL, DBUS_UID_UNSET);
_dbus_return_val_if_fail (_dbus_check_is_valid_bus_name (name), DBUS_UID_UNSET);
_dbus_return_val_if_error_is_set (error, DBUS_UID_UNSET);
message = dbus_message_new_method_call (DBUS_SERVICE_DBUS,
DBUS_PATH_DBUS,
DBUS_INTERFACE_DBUS,
"GetConnectionUnixUser");
if (message == NULL)
{
_DBUS_SET_OOM (error);
return DBUS_UID_UNSET;
}
if (!dbus_message_append_args (message,
DBUS_TYPE_STRING, &name,
DBUS_TYPE_INVALID))
{
dbus_message_unref (message);
_DBUS_SET_OOM (error);
return DBUS_UID_UNSET;
}
reply = dbus_connection_send_with_reply_and_block (connection, message, -1,
error);
dbus_message_unref (message);
if (reply == NULL)
{
_DBUS_ASSERT_ERROR_IS_SET (error);
return DBUS_UID_UNSET;
}
if (dbus_set_error_from_message (error, reply))
{
_DBUS_ASSERT_ERROR_IS_SET (error);
dbus_message_unref (reply);
return DBUS_UID_UNSET;
}
if (!dbus_message_get_args (reply, error,
DBUS_TYPE_UINT32, &uid,
DBUS_TYPE_INVALID))
{
_DBUS_ASSERT_ERROR_IS_SET (error);
dbus_message_unref (reply);
return DBUS_UID_UNSET;
}
dbus_message_unref (reply);
return (unsigned long) uid;
}
/**
* Registers a connection with the bus. This must be the first
* thing an application does when connecting to the message bus.
* If registration succeeds, the unique name will be set,
* and can be obtained using dbus_bus_get_unique_name().
*
* @param connection the connection
* @param error place to store errors
* @returns #TRUE on success
*/
dbus_bool_t
dbus_bus_register (DBusConnection *connection,
DBusError *error)
{
DBusMessage *message, *reply;
char *name;
BusData *bd;
dbus_bool_t retval;
_dbus_return_val_if_fail (connection != NULL, FALSE);
_dbus_return_val_if_error_is_set (error, FALSE);
retval = FALSE;
bd = ensure_bus_data (connection);
if (bd == NULL)
{
_DBUS_SET_OOM (error);
return FALSE;
}
if (bd->unique_name != NULL)
{
_dbus_warn ("Attempt to register the same DBusConnection with the message bus, but it is already registered\n");
/* This isn't an error, it's a programming bug. We'll be nice
* and not _dbus_assert_not_reached()
*/
return TRUE;
}
message = dbus_message_new_method_call (DBUS_SERVICE_DBUS,
DBUS_PATH_DBUS,
DBUS_INTERFACE_DBUS,
"Hello");
if (!message)
{
_DBUS_SET_OOM (error);
return FALSE;
}
reply = dbus_connection_send_with_reply_and_block (connection, message, -1, error);
dbus_message_unref (message);
if (reply == NULL)
goto out;
else if (dbus_set_error_from_message (error, reply))
goto out;
else if (!dbus_message_get_args (reply, error,
DBUS_TYPE_STRING, &name,
DBUS_TYPE_INVALID))
goto out;
bd->unique_name = _dbus_strdup (name);
if (bd->unique_name == NULL)
{
_DBUS_SET_OOM (error);
goto out;
}
retval = TRUE;
out:
if (reply)
dbus_message_unref (reply);
if (!retval)
_DBUS_ASSERT_ERROR_IS_SET (error);
return retval;
}
/**
* Connects to a bus daemon and registers the client with it. If a
* connection to the bus already exists, then that connection is
* returned. Caller owns a reference to the bus.
*
* @todo alex thinks we should nullify the connection when we get a disconnect-message.
*
* @param type bus type
* @param error address where an error can be returned.
* @returns a DBusConnection with new ref
*/
DBusConnection *
dbus_bus_get (DBusBusType type,
DBusError *error)
{
const char *address;
DBusConnection *connection;
BusData *bd;
DBusBusType address_type;
_dbus_return_val_if_fail (type >= 0 && type < N_BUS_TYPES, NULL);
_dbus_return_val_if_error_is_set (error, NULL);
_DBUS_LOCK (bus);
if (!init_connections_unlocked ())
{
_DBUS_UNLOCK (bus);
_DBUS_SET_OOM (error);
return NULL;
}
/* We want to use the activation address even if the
* activating bus is the session or system bus,
* per the spec.
*/
address_type = type;
/* Use the real type of the activation bus for getting its
* connection, but only if the real type's address is available. (If
* the activating bus isn't a well-known bus then
* activation_bus_type == DBUS_BUS_STARTER)
*/
if (type == DBUS_BUS_STARTER &&
bus_connection_addresses[activation_bus_type] != NULL)
type = activation_bus_type;
if (bus_connections[type] != NULL)
{
connection = bus_connections[type];
dbus_connection_ref (connection);
_DBUS_UNLOCK (bus);
return connection;
}
address = bus_connection_addresses[address_type];
if (address == NULL)
{
dbus_set_error (error, DBUS_ERROR_FAILED,
"Unable to determine the address of the message bus");
_DBUS_UNLOCK (bus);
return NULL;
}
connection = dbus_connection_open (address, error);
if (!connection)
{
_DBUS_ASSERT_ERROR_IS_SET (error);
_DBUS_UNLOCK (bus);
return NULL;
}
/* By default we're bound to the lifecycle of
* the message bus.
*/
dbus_connection_set_exit_on_disconnect (connection,
TRUE);
if (!dbus_bus_register (connection, error))
{
_DBUS_ASSERT_ERROR_IS_SET (error);
dbus_connection_close (connection);
dbus_connection_unref (connection);
_DBUS_UNLOCK (bus);
return NULL;
}
bus_connections[type] = connection;
bd = ensure_bus_data (connection);
_dbus_assert (bd != NULL);
bd->is_well_known = TRUE;
_DBUS_UNLOCK (bus);
return connection;
}
