1 /* -*- mode: C; c-file-style: "gnu" -*- */
2 /* dbus-bus.c Convenience functions for communicating with the bus.
4 * Copyright (C) 2003 CodeFactory AB
5 * Copyright (C) 2003 Red Hat, Inc.
7 * Licensed under the Academic Free License version 2.1
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
26 #include "dbus-protocol.h"
27 #include "dbus-internals.h"
28 #include "dbus-message.h"
29 #include "dbus-marshal-validate.h"
30 #include "dbus-threads-internal.h"
31 #include "dbus-connection-internal.h"
35 * @defgroup DBusBus Message bus APIs
37 * @brief Functions for communicating with the message bus
39 * @todo right now the default address of the system bus is hardcoded,
40 * so if you change it in the global config file suddenly you have to
41 * set DBUS_SYSTEM_BUS_ADDRESS env variable. Might be nice if the
42 * client lib somehow read the config file, or if the bus on startup
43 * somehow wrote out its address to a well-known spot, but might also
48 * @defgroup DBusBusInternals Message bus APIs internals
49 * @ingroup DBusInternals
50 * @brief Internals of functions for communicating with the message bus
56 * Block of message-bus-related data we attach to each
57 * #DBusConnection used with these convenience functions.
62 DBusConnection *connection; /**< Connection we're associated with */
63 char *unique_name; /**< Unique name of this connection */
65 unsigned int is_well_known : 1; /**< Is one of the well-known connections in our global array */
68 /** The slot we have reserved to store BusData.
70 static dbus_int32_t bus_data_slot = -1;
72 /** Number of bus types */
75 static DBusConnection *bus_connections[N_BUS_TYPES];
76 static char *bus_connection_addresses[N_BUS_TYPES] = { NULL, NULL, NULL };
78 static DBusBusType activation_bus_type = DBUS_BUS_STARTER;
80 static dbus_bool_t initialized = FALSE;
83 * Lock for globals in this file
85 _DBUS_DEFINE_GLOBAL_LOCK (bus);
88 addresses_shutdown_func (void *data)
93 while (i < N_BUS_TYPES)
95 if (bus_connections[i] != NULL)
96 _dbus_warn ("dbus_shutdown() called but connections were still live!");
98 dbus_free (bus_connection_addresses[i]);
99 bus_connection_addresses[i] = NULL;
103 activation_bus_type = DBUS_BUS_STARTER;
107 get_from_env (char **connection_p,
112 _dbus_assert (*connection_p == NULL);
114 s = _dbus_getenv (env_var);
115 if (s == NULL || *s == '\0')
116 return TRUE; /* successfully didn't use the env var */
119 *connection_p = _dbus_strdup (s);
120 return *connection_p != NULL;
125 init_connections_unlocked (void)
133 while (i < N_BUS_TYPES)
135 bus_connections[i] = NULL;
139 /* Don't init these twice, we may run this code twice if
140 * init_connections_unlocked() fails midway through.
141 * In practice, each block below should contain only one
142 * "return FALSE" or running through twice may not
146 if (bus_connection_addresses[DBUS_BUS_SYSTEM] == NULL)
148 _dbus_verbose ("Filling in system bus address...\n");
150 if (!get_from_env (&bus_connection_addresses[DBUS_BUS_SYSTEM],
151 "DBUS_SYSTEM_BUS_ADDRESS"))
156 if (bus_connection_addresses[DBUS_BUS_SYSTEM] == NULL)
158 /* Use default system bus address if none set in environment */
159 bus_connection_addresses[DBUS_BUS_SYSTEM] =
160 _dbus_strdup (DBUS_SYSTEM_BUS_DEFAULT_ADDRESS);
162 if (bus_connection_addresses[DBUS_BUS_SYSTEM] == NULL)
165 _dbus_verbose (" used default system bus \"%s\"\n",
166 bus_connection_addresses[DBUS_BUS_SYSTEM]);
169 _dbus_verbose (" used env var system bus \"%s\"\n",
170 bus_connection_addresses[DBUS_BUS_SYSTEM]);
172 if (bus_connection_addresses[DBUS_BUS_SESSION] == NULL)
174 _dbus_verbose ("Filling in session bus address...\n");
176 if (!get_from_env (&bus_connection_addresses[DBUS_BUS_SESSION],
177 "DBUS_SESSION_BUS_ADDRESS"))
180 if (bus_connection_addresses[DBUS_BUS_SESSION] == NULL)
181 bus_connection_addresses[DBUS_BUS_SESSION] =
182 _dbus_strdup (DBUS_SESSION_BUS_DEFAULT_ADDRESS);
184 if (bus_connection_addresses[DBUS_BUS_SESSION] == NULL)
187 _dbus_verbose (" \"%s\"\n", bus_connection_addresses[DBUS_BUS_SESSION] ?
188 bus_connection_addresses[DBUS_BUS_SESSION] : "none set");
191 if (bus_connection_addresses[DBUS_BUS_STARTER] == NULL)
193 _dbus_verbose ("Filling in activation bus address...\n");
195 if (!get_from_env (&bus_connection_addresses[DBUS_BUS_STARTER],
196 "DBUS_STARTER_ADDRESS"))
199 _dbus_verbose (" \"%s\"\n", bus_connection_addresses[DBUS_BUS_STARTER] ?
200 bus_connection_addresses[DBUS_BUS_STARTER] : "none set");
204 if (bus_connection_addresses[DBUS_BUS_STARTER] != NULL)
206 s = _dbus_getenv ("DBUS_STARTER_BUS_TYPE");
210 _dbus_verbose ("Bus activation type was set to \"%s\"\n", s);
212 if (strcmp (s, "system") == 0)
213 activation_bus_type = DBUS_BUS_SYSTEM;
214 else if (strcmp (s, "session") == 0)
215 activation_bus_type = DBUS_BUS_SESSION;
220 /* Default to the session bus instead if available */
221 if (bus_connection_addresses[DBUS_BUS_SESSION] != NULL)
223 bus_connection_addresses[DBUS_BUS_STARTER] =
224 _dbus_strdup (bus_connection_addresses[DBUS_BUS_SESSION]);
225 if (bus_connection_addresses[DBUS_BUS_STARTER] == NULL)
230 /* If we return FALSE we have to be sure that restarting
231 * the above code will work right
234 if (!_dbus_setenv ("DBUS_ACTIVATION_ADDRESS", NULL))
237 if (!_dbus_setenv ("DBUS_ACTIVATION_BUS_TYPE", NULL))
240 if (!_dbus_register_shutdown_func (addresses_shutdown_func,
251 bus_data_free (void *data)
255 if (bd->is_well_known)
259 /* We may be stored in more than one slot */
261 while (i < N_BUS_TYPES)
263 if (bus_connections[i] == bd->connection)
264 bus_connections[i] = NULL;
271 dbus_free (bd->unique_name);
274 dbus_connection_free_data_slot (&bus_data_slot);
278 ensure_bus_data (DBusConnection *connection)
282 if (!dbus_connection_allocate_data_slot (&bus_data_slot))
285 bd = dbus_connection_get_data (connection, bus_data_slot);
288 bd = dbus_new0 (BusData, 1);
291 dbus_connection_free_data_slot (&bus_data_slot);
295 bd->connection = connection;
297 if (!dbus_connection_set_data (connection, bus_data_slot, bd,
301 dbus_connection_free_data_slot (&bus_data_slot);
305 /* Data slot refcount now held by the BusData */
309 dbus_connection_free_data_slot (&bus_data_slot);
316 * Internal function that checks to see if this
317 * is a shared connection owned by the bus and if it is unref it.
319 * @param connection a connection that has been disconnected.
322 _dbus_bus_notify_shared_connection_disconnected_unlocked (DBusConnection *connection)
328 /* We are expecting to have the connection saved in only one of these
329 * slots, but someone could in a pathological case set system and session
330 * bus to the same bus or something. Or set one of them to the starter
331 * bus without setting the starter bus type in the env variable.
332 * So we don't break the loop as soon as we find a match.
334 for (i = 0; i < N_BUS_TYPES; ++i)
336 if (bus_connections[i] == connection)
338 bus_connections[i] = NULL;
339 _dbus_connection_unref_unlocked (connection);
346 static DBusConnection *
347 internal_bus_get (DBusBusType type,
352 DBusConnection *connection;
354 DBusBusType address_type;
356 _dbus_return_val_if_fail (type >= 0 && type < N_BUS_TYPES, NULL);
357 _dbus_return_val_if_error_is_set (error, NULL);
361 if (!init_connections_unlocked ())
364 _DBUS_SET_OOM (error);
368 /* We want to use the activation address even if the
369 * activating bus is the session or system bus,
374 /* Use the real type of the activation bus for getting its
375 * connection, but only if the real type's address is available. (If
376 * the activating bus isn't a well-known bus then
377 * activation_bus_type == DBUS_BUS_STARTER)
379 if (type == DBUS_BUS_STARTER &&
380 bus_connection_addresses[activation_bus_type] != NULL)
381 type = activation_bus_type;
383 if (!private && bus_connections[type] != NULL)
385 connection = bus_connections[type];
386 dbus_connection_ref (connection);
392 address = bus_connection_addresses[address_type];
395 dbus_set_error (error, DBUS_ERROR_FAILED,
396 "Unable to determine the address of the message bus (try 'man dbus-launch' and 'man dbus-daemon' for help)");
402 connection = dbus_connection_open_private (address, error);
404 connection = dbus_connection_open (address, error);
408 _DBUS_ASSERT_ERROR_IS_SET (error);
413 /* By default we're bound to the lifecycle of
416 dbus_connection_set_exit_on_disconnect (connection,
419 if (!dbus_bus_register (connection, error))
421 _DBUS_ASSERT_ERROR_IS_SET (error);
422 _dbus_connection_close_possibly_shared (connection);
423 dbus_connection_unref (connection);
431 /* get a hard ref to the connection */
432 bus_connections[type] = connection;
433 dbus_connection_ref (bus_connections[type]);
436 bd = ensure_bus_data (connection);
437 _dbus_assert (bd != NULL);
439 bd->is_well_known = TRUE;
443 /* Return a reference to the caller */
448 /** @} */ /* end of implementation details docs */
451 * @addtogroup DBusBus
456 * Connects to a bus daemon and registers the client with it. If a
457 * connection to the bus already exists, then that connection is
458 * returned. The caller of this function owns a reference to the bus.
460 * The caller may NOT call dbus_connection_close() on this connection;
461 * see dbus_connection_open() and dbus_connection_close() for details
464 * If this function obtains a new connection object never before
465 * returned from dbus_bus_get(), it will call
466 * dbus_connection_set_exit_on_disconnect(), so the application
467 * will exit if the connection closes. You can undo this
468 * by calling dbus_connection_set_exit_on_disconnect() yourself
469 * after you get the connection.
471 * @param type bus type
472 * @param error address where an error can be returned.
473 * @returns a #DBusConnection with new ref
476 dbus_bus_get (DBusBusType type,
479 return internal_bus_get (type, FALSE, error);
483 * Connects to a bus daemon and registers the client with it as with dbus_bus_register().
484 * Unlike dbus_bus_get(), always creates a new connection. This connection
485 * will not be saved or recycled by libdbus. Caller owns a reference
486 * to the bus and must either close it or know it to be closed
487 * prior to releasing this reference.
489 * See dbus_connection_open_private() for more details on when to
490 * close and unref this connection.
492 * This function calls
493 * dbus_connection_set_exit_on_disconnect() on the new connection, so the application
494 * will exit if the connection closes. You can undo this
495 * by calling dbus_connection_set_exit_on_disconnect() yourself
496 * after you get the connection.
498 * @param type bus type
499 * @param error address where an error can be returned.
500 * @returns a DBusConnection with new ref
503 dbus_bus_get_private (DBusBusType type,
506 return internal_bus_get (type, TRUE, error);
510 * Registers a connection with the bus. This must be the first
511 * thing an application does when connecting to the message bus.
512 * If registration succeeds, the unique name will be set,
513 * and can be obtained using dbus_bus_get_unique_name().
515 * If you use dbus_bus_get() or dbus_bus_get_private() this
516 * function will be called for you.
518 * @param connection the connection
519 * @param error place to store errors
520 * @returns #TRUE on success
523 dbus_bus_register (DBusConnection *connection,
526 DBusMessage *message, *reply;
531 _dbus_return_val_if_fail (connection != NULL, FALSE);
532 _dbus_return_val_if_error_is_set (error, FALSE);
536 bd = ensure_bus_data (connection);
539 _DBUS_SET_OOM (error);
543 if (bd->unique_name != NULL)
545 _dbus_warn ("Attempt to register the same DBusConnection with the message bus, but it is already registered\n");
546 /* This isn't an error, it's a programming bug. We'll be nice
547 * and not _dbus_assert_not_reached()
552 message = dbus_message_new_method_call (DBUS_SERVICE_DBUS,
559 _DBUS_SET_OOM (error);
563 reply = dbus_connection_send_with_reply_and_block (connection, message, -1, error);
565 dbus_message_unref (message);
569 else if (dbus_set_error_from_message (error, reply))
571 else if (!dbus_message_get_args (reply, error,
572 DBUS_TYPE_STRING, &name,
576 bd->unique_name = _dbus_strdup (name);
577 if (bd->unique_name == NULL)
579 _DBUS_SET_OOM (error);
587 dbus_message_unref (reply);
590 _DBUS_ASSERT_ERROR_IS_SET (error);
597 * Sets the unique name of the connection. Can only be used if you
598 * registered with the bus manually (i.e. if you did not call
599 * dbus_bus_register()). Can only be called once per connection.
601 * @param connection the connection
602 * @param unique_name the unique name
603 * @returns #FALSE if not enough memory
606 dbus_bus_set_unique_name (DBusConnection *connection,
607 const char *unique_name)
611 _dbus_return_val_if_fail (connection != NULL, FALSE);
612 _dbus_return_val_if_fail (unique_name != NULL, FALSE);
614 bd = ensure_bus_data (connection);
618 _dbus_assert (bd->unique_name == NULL);
620 bd->unique_name = _dbus_strdup (unique_name);
621 return bd->unique_name != NULL;
625 * Gets the unique name of the connection. Only possible after the
626 * connection has been registered with the message bus.
628 * The name remains valid for the duration of the connection and
629 * should not be freed by the caller.
631 * @param connection the connection
632 * @returns the unique name or NULL on error
635 dbus_bus_get_unique_name (DBusConnection *connection)
639 _dbus_return_val_if_fail (connection != NULL, NULL);
641 bd = ensure_bus_data (connection);
645 return bd->unique_name;
649 * Asks the bus to return the uid of the named
652 * Not going to work on Windows, the bus should return
655 * @param connection the connection
656 * @param name a name owned by the connection
657 * @param error location to store the error
658 * @returns a result code, -1 if error is set
661 dbus_bus_get_unix_user (DBusConnection *connection,
665 DBusMessage *message, *reply;
668 _dbus_return_val_if_fail (connection != NULL, DBUS_UID_UNSET);
669 _dbus_return_val_if_fail (name != NULL, DBUS_UID_UNSET);
670 _dbus_return_val_if_fail (_dbus_check_is_valid_bus_name (name), DBUS_UID_UNSET);
671 _dbus_return_val_if_error_is_set (error, DBUS_UID_UNSET);
673 message = dbus_message_new_method_call (DBUS_SERVICE_DBUS,
676 "GetConnectionUnixUser");
680 _DBUS_SET_OOM (error);
681 return DBUS_UID_UNSET;
684 if (!dbus_message_append_args (message,
685 DBUS_TYPE_STRING, &name,
688 dbus_message_unref (message);
689 _DBUS_SET_OOM (error);
690 return DBUS_UID_UNSET;
693 reply = dbus_connection_send_with_reply_and_block (connection, message, -1,
696 dbus_message_unref (message);
700 _DBUS_ASSERT_ERROR_IS_SET (error);
701 return DBUS_UID_UNSET;
704 if (dbus_set_error_from_message (error, reply))
706 _DBUS_ASSERT_ERROR_IS_SET (error);
707 dbus_message_unref (reply);
708 return DBUS_UID_UNSET;
711 if (!dbus_message_get_args (reply, error,
712 DBUS_TYPE_UINT32, &uid,
715 _DBUS_ASSERT_ERROR_IS_SET (error);
716 dbus_message_unref (reply);
717 return DBUS_UID_UNSET;
720 dbus_message_unref (reply);
722 return (unsigned long) uid;
727 * Asks the bus to assign the given name to this connection by invoking
728 * the RequestName method on the bus. This method is fully documented
729 * in the D-Bus specification. For quick reference, the flags and
730 * result codes are discussed here, but the specification is the
731 * canonical version of this information.
733 * The #DBUS_NAME_FLAG_ALLOW_REPLACEMENT flag indicates that the caller
734 * will allow other services to take over the name from the current owner.
736 * The #DBUS_NAME_FLAG_REPLACE_EXISTING flag indicates that the caller
737 * would like to take over the name from the current owner.
738 * If the current name owner did not use #DBUS_NAME_FLAG_ALLOW_REPLACEMENT
739 * then this flag indicates that the caller would like to be placed
740 * in the queue to own the name when the current owner lets go.
742 * If no flags are given, an application will receive the requested
743 * name only if the name is currently unowned; it will NOT give
744 * up the name if another application asks to take it over using
745 * #DBUS_NAME_FLAG_REPLACE_EXISTING.
747 * This function returns a result code. The possible result codes
750 * #DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER means that the name had no
751 * existing owner, and the caller is now the primary owner; or that
752 * the name had an owner, and the caller specified
753 * #DBUS_NAME_FLAG_REPLACE_EXISTING, and the current owner
754 * specified #DBUS_NAME_FLAG_ALLOW_REPLACEMENT.
756 * #DBUS_REQUEST_NAME_REPLY_IN_QUEUE happens only if the caller does NOT
757 * specify #DBUS_NAME_FLAG_DO_NOT_QUEUE and either the current owner
758 * did NOT specify #DBUS_NAME_FLAG_ALLOW_REPLACEMENT or the caller did NOT
759 * specify #DBUS_NAME_FLAG_REPLACE_EXISTING. In this case the caller ends up
760 * in a queue to own the name after the current owner gives it up.
762 * #DBUS_REQUEST_NAME_REPLY_EXISTS happens if the name has an owner
763 * already and the caller specifies #DBUS_NAME_FLAG_DO_NOT_QUEUE
764 * and either the current owner has NOT specified
765 * #DBUS_NAME_FLAG_ALLOW_REPLACEMENT or the caller did NOT specify
766 * #DBUS_NAME_FLAG_REPLACE_EXISTING.
768 * #DBUS_REQUEST_NAME_REPLY_ALREADY_OWNER happens if an application
769 * requests a name it already owns.
771 * When a service represents an application, say "text editor," then
772 * it should specify #DBUS_NAME_FLAG_ALLOW_REPLACEMENT if it wants
773 * the last editor started to be the user's editor vs. the first one
774 * started. Then any editor that can be the user's editor should
775 * specify #DBUS_NAME_FLAG_REPLACE_EXISTING to either take over
776 * (last-started-wins) or be queued up (first-started-wins) according
777 * to whether #DBUS_NAME_FLAG_ALLOW_REPLACEMENT was given.
779 * @param connection the connection
780 * @param name the name to request
782 * @param error location to store the error
783 * @returns a result code, -1 if error is set
786 dbus_bus_request_name (DBusConnection *connection,
791 DBusMessage *message, *reply;
792 dbus_uint32_t result;
794 _dbus_return_val_if_fail (connection != NULL, 0);
795 _dbus_return_val_if_fail (name != NULL, 0);
796 _dbus_return_val_if_fail (_dbus_check_is_valid_bus_name (name), 0);
797 _dbus_return_val_if_error_is_set (error, 0);
799 message = dbus_message_new_method_call (DBUS_SERVICE_DBUS,
806 _DBUS_SET_OOM (error);
810 if (!dbus_message_append_args (message,
811 DBUS_TYPE_STRING, &name,
812 DBUS_TYPE_UINT32, &flags,
815 dbus_message_unref (message);
816 _DBUS_SET_OOM (error);
820 reply = dbus_connection_send_with_reply_and_block (connection, message, -1,
823 dbus_message_unref (message);
827 _DBUS_ASSERT_ERROR_IS_SET (error);
831 if (dbus_set_error_from_message (error, reply))
833 _DBUS_ASSERT_ERROR_IS_SET (error);
834 dbus_message_unref (reply);
838 if (!dbus_message_get_args (reply, error,
839 DBUS_TYPE_UINT32, &result,
842 _DBUS_ASSERT_ERROR_IS_SET (error);
843 dbus_message_unref (reply);
847 dbus_message_unref (reply);
854 * Asks the bus to unassign the given name to this connection by invoking
855 * the ReleaseName method on the bus. This method is fully documented
856 * in the D-Bus specification.
858 * @param connection the connection
859 * @param name the name to remove
860 * @param error location to store the error
861 * @returns a result code, -1 if error is set
864 dbus_bus_release_name (DBusConnection *connection,
868 DBusMessage *message, *reply;
869 dbus_uint32_t result;
871 _dbus_return_val_if_fail (connection != NULL, 0);
872 _dbus_return_val_if_fail (name != NULL, 0);
873 _dbus_return_val_if_fail (_dbus_check_is_valid_bus_name (name), 0);
874 _dbus_return_val_if_error_is_set (error, 0);
876 message = dbus_message_new_method_call (DBUS_SERVICE_DBUS,
883 _DBUS_SET_OOM (error);
887 if (!dbus_message_append_args (message,
888 DBUS_TYPE_STRING, &name,
891 dbus_message_unref (message);
892 _DBUS_SET_OOM (error);
896 reply = dbus_connection_send_with_reply_and_block (connection, message, -1,
899 dbus_message_unref (message);
903 _DBUS_ASSERT_ERROR_IS_SET (error);
907 if (dbus_set_error_from_message (error, reply))
909 _DBUS_ASSERT_ERROR_IS_SET (error);
910 dbus_message_unref (reply);
914 if (!dbus_message_get_args (reply, error,
915 DBUS_TYPE_UINT32, &result,
918 _DBUS_ASSERT_ERROR_IS_SET (error);
919 dbus_message_unref (reply);
923 dbus_message_unref (reply);
929 * Checks whether a certain name has an owner.
931 * @param connection the connection
932 * @param name the name
933 * @param error location to store any errors
934 * @returns #TRUE if the name exists, #FALSE if not or on error
937 dbus_bus_name_has_owner (DBusConnection *connection,
941 DBusMessage *message, *reply;
944 _dbus_return_val_if_fail (connection != NULL, FALSE);
945 _dbus_return_val_if_fail (name != NULL, FALSE);
946 _dbus_return_val_if_fail (_dbus_check_is_valid_bus_name (name), FALSE);
947 _dbus_return_val_if_error_is_set (error, FALSE);
949 message = dbus_message_new_method_call (DBUS_SERVICE_DBUS,
955 _DBUS_SET_OOM (error);
959 if (!dbus_message_append_args (message,
960 DBUS_TYPE_STRING, &name,
963 dbus_message_unref (message);
964 _DBUS_SET_OOM (error);
968 reply = dbus_connection_send_with_reply_and_block (connection, message, -1, error);
969 dbus_message_unref (message);
973 _DBUS_ASSERT_ERROR_IS_SET (error);
977 if (!dbus_message_get_args (reply, error,
978 DBUS_TYPE_BOOLEAN, &exists,
981 _DBUS_ASSERT_ERROR_IS_SET (error);
982 dbus_message_unref (reply);
986 dbus_message_unref (reply);
991 * Starts a service that will request ownership of the given name.
992 * The returned result will be one of be one of
993 * #DBUS_START_REPLY_SUCCESS or #DBUS_START_REPLY_ALREADY_RUNNING if
994 * successful. Pass #NULL if you don't care about the result.
996 * The flags parameter is for future expansion, currently you should
999 * @param connection the connection
1000 * @param name the name we want the new service to request
1001 * @param flags the flags (should always be 0 for now)
1002 * @param result a place to store the result or #NULL
1003 * @param error location to store any errors
1004 * @returns #TRUE if the activation succeeded, #FALSE if not
1007 dbus_bus_start_service_by_name (DBusConnection *connection,
1009 dbus_uint32_t flags,
1010 dbus_uint32_t *result,
1016 _dbus_return_val_if_fail (connection != NULL, FALSE);
1017 _dbus_return_val_if_fail (_dbus_check_is_valid_bus_name (name), FALSE);
1019 msg = dbus_message_new_method_call (DBUS_SERVICE_DBUS,
1021 DBUS_INTERFACE_DBUS,
1022 "StartServiceByName");
1024 if (!dbus_message_append_args (msg, DBUS_TYPE_STRING, &name,
1025 DBUS_TYPE_UINT32, &flags, DBUS_TYPE_INVALID))
1027 dbus_message_unref (msg);
1028 _DBUS_SET_OOM (error);
1032 reply = dbus_connection_send_with_reply_and_block (connection, msg,
1034 dbus_message_unref (msg);
1038 _DBUS_ASSERT_ERROR_IS_SET (error);
1042 if (dbus_set_error_from_message (error, reply))
1044 _DBUS_ASSERT_ERROR_IS_SET (error);
1045 dbus_message_unref (reply);
1049 if (result != NULL &&
1050 !dbus_message_get_args (reply, error, DBUS_TYPE_UINT32,
1051 result, DBUS_TYPE_INVALID))
1053 _DBUS_ASSERT_ERROR_IS_SET (error);
1054 dbus_message_unref (reply);
1058 dbus_message_unref (reply);
1063 send_no_return_values (DBusConnection *connection,
1069 /* Block to check success codepath */
1072 reply = dbus_connection_send_with_reply_and_block (connection, msg,
1076 _DBUS_ASSERT_ERROR_IS_SET (error);
1078 dbus_message_unref (reply);
1082 /* Silently-fail nonblocking codepath */
1083 dbus_message_set_no_reply (msg, TRUE);
1084 dbus_connection_send (connection, msg, NULL);
1089 * Adds a match rule to match messages going through the message bus.
1090 * The "rule" argument is the string form of a match rule.
1092 * If you pass #NULL for the error, this function will not
1093 * block; the match thus won't be added until you flush the
1094 * connection, and if there's an error adding the match
1095 * (only possible error is lack of resources in the bus),
1096 * you won't find out about it.
1098 * If you pass non-#NULL for the error this function will
1099 * block until it gets a reply.
1101 * Normal API conventions would have the function return
1102 * a boolean value indicating whether the error was set,
1103 * but that would require blocking always to determine
1106 * The AddMatch method is fully documented in the D-Bus
1107 * specification. For quick reference, the format of the
1108 * match rules is discussed here, but the specification
1109 * is the canonical version of this information.
1111 * Rules are specified as a string of comma separated
1112 * key/value pairs. An example is
1113 * "type='signal',sender='org.freedesktop.DBus',
1114 * interface='org.freedesktop.DBus',member='Foo',
1115 * path='/bar/foo',destination=':452345.34'"
1117 * Possible keys you can match on are type, sender,
1118 * interface, member, path, destination and the special
1119 * arg keys. Excluding a key from the rule indicates
1120 * a wildcard match. For instance excluding the
1121 * the member from a match rule but adding a sender would
1122 * let all messages from that sender through.
1124 * Matches are inclusive not exclusive so as long as one
1125 * rule matches the message will get through. It is important
1126 * to note this because every time a message is received the
1127 * application will be paged into memory to process it. This
1128 * can cause performance problems such as draining batteries
1129 * on embedded platforms.
1131 * The special arg keys are used for further restricting the
1132 * match based on the parameters sent by the signal or method.
1133 * For instance arg1='foo' will check the first argument,
1134 * arg2='bar' the second and so on. For performance reasons
1135 * there is a set limit on the highest number parameter that
1136 * can be checked which is set in dbus-protocol.h
1138 * @param connection connection to the message bus
1139 * @param rule textual form of match rule
1140 * @param error location to store any errors
1143 dbus_bus_add_match (DBusConnection *connection,
1149 _dbus_return_if_fail (rule != NULL);
1151 msg = dbus_message_new_method_call (DBUS_SERVICE_DBUS,
1153 DBUS_INTERFACE_DBUS,
1158 _DBUS_SET_OOM (error);
1162 if (!dbus_message_append_args (msg, DBUS_TYPE_STRING, &rule,
1165 dbus_message_unref (msg);
1166 _DBUS_SET_OOM (error);
1170 send_no_return_values (connection, msg, error);
1172 dbus_message_unref (msg);
1176 * Removes a previously-added match rule "by value" (the most
1177 * recently-added identical rule gets removed). The "rule" argument
1178 * is the string form of a match rule.
1180 * If you pass #NULL for the error, this function will not
1181 * block; otherwise it will. See detailed explanation in
1182 * docs for dbus_bus_add_match().
1184 * @param connection connection to the message bus
1185 * @param rule textual form of match rule
1186 * @param error location to store any errors
1189 dbus_bus_remove_match (DBusConnection *connection,
1195 _dbus_return_if_fail (rule != NULL);
1197 msg = dbus_message_new_method_call (DBUS_SERVICE_DBUS,
1199 DBUS_INTERFACE_DBUS,
1202 if (!dbus_message_append_args (msg, DBUS_TYPE_STRING, &rule,
1205 dbus_message_unref (msg);
1206 _DBUS_SET_OOM (error);
1210 send_no_return_values (connection, msg, error);
1212 dbus_message_unref (msg);