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_check_failed ("dbus_shutdown() called but connections were still live. This probably means the application did not drop all its references to bus connections.\n");
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 */
260 /* This should now be impossible - these slots are supposed to
261 * be cleared on disconnect, so should not need to be cleared on
265 while (i < N_BUS_TYPES)
267 if (bus_connections[i] == bd->connection)
268 bus_connections[i] = NULL;
275 dbus_free (bd->unique_name);
278 dbus_connection_free_data_slot (&bus_data_slot);
282 ensure_bus_data (DBusConnection *connection)
286 if (!dbus_connection_allocate_data_slot (&bus_data_slot))
289 bd = dbus_connection_get_data (connection, bus_data_slot);
292 bd = dbus_new0 (BusData, 1);
295 dbus_connection_free_data_slot (&bus_data_slot);
299 bd->connection = connection;
301 if (!dbus_connection_set_data (connection, bus_data_slot, bd,
305 dbus_connection_free_data_slot (&bus_data_slot);
309 /* Data slot refcount now held by the BusData */
313 dbus_connection_free_data_slot (&bus_data_slot);
320 * Internal function that checks to see if this
321 * is a shared connection owned by the bus and if it is unref it.
323 * @param connection a connection that has been disconnected.
326 _dbus_bus_notify_shared_connection_disconnected_unlocked (DBusConnection *connection)
332 /* We are expecting to have the connection saved in only one of these
333 * slots, but someone could in a pathological case set system and session
334 * bus to the same bus or something. Or set one of them to the starter
335 * bus without setting the starter bus type in the env variable.
336 * So we don't break the loop as soon as we find a match.
338 for (i = 0; i < N_BUS_TYPES; ++i)
340 if (bus_connections[i] == connection)
342 bus_connections[i] = NULL;
349 static DBusConnection *
350 internal_bus_get (DBusBusType type,
355 DBusConnection *connection;
357 DBusBusType address_type;
359 _dbus_return_val_if_fail (type >= 0 && type < N_BUS_TYPES, NULL);
360 _dbus_return_val_if_error_is_set (error, NULL);
364 if (!init_connections_unlocked ())
367 _DBUS_SET_OOM (error);
371 /* We want to use the activation address even if the
372 * activating bus is the session or system bus,
377 /* Use the real type of the activation bus for getting its
378 * connection, but only if the real type's address is available. (If
379 * the activating bus isn't a well-known bus then
380 * activation_bus_type == DBUS_BUS_STARTER)
382 if (type == DBUS_BUS_STARTER &&
383 bus_connection_addresses[activation_bus_type] != NULL)
384 type = activation_bus_type;
386 if (!private && bus_connections[type] != NULL)
388 connection = bus_connections[type];
389 dbus_connection_ref (connection);
395 address = bus_connection_addresses[address_type];
398 dbus_set_error (error, DBUS_ERROR_FAILED,
399 "Unable to determine the address of the message bus (try 'man dbus-launch' and 'man dbus-daemon' for help)");
405 connection = dbus_connection_open_private (address, error);
407 connection = dbus_connection_open (address, error);
411 _DBUS_ASSERT_ERROR_IS_SET (error);
416 /* By default we're bound to the lifecycle of
419 dbus_connection_set_exit_on_disconnect (connection,
422 if (!dbus_bus_register (connection, error))
424 _DBUS_ASSERT_ERROR_IS_SET (error);
425 _dbus_connection_close_possibly_shared (connection);
426 dbus_connection_unref (connection);
434 /* store a weak ref to the connection (dbus-connection.c is
435 * supposed to have a strong ref that it drops on disconnect,
436 * since this is a shared connection)
438 bus_connections[type] = connection;
441 bd = ensure_bus_data (connection);
442 _dbus_assert (bd != NULL);
444 bd->is_well_known = TRUE;
448 /* Return a reference to the caller */
453 /** @} */ /* end of implementation details docs */
456 * @addtogroup DBusBus
461 * Connects to a bus daemon and registers the client with it. If a
462 * connection to the bus already exists, then that connection is
463 * returned. The caller of this function owns a reference to the bus.
465 * The caller may NOT call dbus_connection_close() on this connection;
466 * see dbus_connection_open() and dbus_connection_close() for details
469 * If this function obtains a new connection object never before
470 * returned from dbus_bus_get(), it will call
471 * dbus_connection_set_exit_on_disconnect(), so the application
472 * will exit if the connection closes. You can undo this
473 * by calling dbus_connection_set_exit_on_disconnect() yourself
474 * after you get the connection.
476 * @param type bus type
477 * @param error address where an error can be returned.
478 * @returns a #DBusConnection with new ref
481 dbus_bus_get (DBusBusType type,
484 return internal_bus_get (type, FALSE, error);
488 * Connects to a bus daemon and registers the client with it as with dbus_bus_register().
489 * Unlike dbus_bus_get(), always creates a new connection. This connection
490 * will not be saved or recycled by libdbus. Caller owns a reference
491 * to the bus and must either close it or know it to be closed
492 * prior to releasing this reference.
494 * See dbus_connection_open_private() for more details on when to
495 * close and unref this connection.
497 * This function calls
498 * dbus_connection_set_exit_on_disconnect() on the new connection, so the application
499 * will exit if the connection closes. You can undo this
500 * by calling dbus_connection_set_exit_on_disconnect() yourself
501 * after you get the connection.
503 * @param type bus type
504 * @param error address where an error can be returned.
505 * @returns a DBusConnection with new ref
508 dbus_bus_get_private (DBusBusType type,
511 return internal_bus_get (type, TRUE, error);
515 * Registers a connection with the bus. This must be the first
516 * thing an application does when connecting to the message bus.
517 * If registration succeeds, the unique name will be set,
518 * and can be obtained using dbus_bus_get_unique_name().
520 * If you use dbus_bus_get() or dbus_bus_get_private() this
521 * function will be called for you.
523 * @param connection the connection
524 * @param error place to store errors
525 * @returns #TRUE on success
528 dbus_bus_register (DBusConnection *connection,
531 DBusMessage *message, *reply;
536 _dbus_return_val_if_fail (connection != NULL, FALSE);
537 _dbus_return_val_if_error_is_set (error, FALSE);
541 bd = ensure_bus_data (connection);
544 _DBUS_SET_OOM (error);
548 if (bd->unique_name != NULL)
550 _dbus_warn_check_failed ("Attempt to register the same DBusConnection %s with the message bus a second time.\n",
552 /* This isn't an error, it's a programming bug. so return TRUE */
556 message = dbus_message_new_method_call (DBUS_SERVICE_DBUS,
563 _DBUS_SET_OOM (error);
567 reply = dbus_connection_send_with_reply_and_block (connection, message, -1, error);
569 dbus_message_unref (message);
573 else if (dbus_set_error_from_message (error, reply))
575 else if (!dbus_message_get_args (reply, error,
576 DBUS_TYPE_STRING, &name,
580 bd->unique_name = _dbus_strdup (name);
581 if (bd->unique_name == NULL)
583 _DBUS_SET_OOM (error);
591 dbus_message_unref (reply);
594 _DBUS_ASSERT_ERROR_IS_SET (error);
601 * Sets the unique name of the connection. Can only be used if you
602 * registered with the bus manually (i.e. if you did not call
603 * dbus_bus_register()). Can only be called once per connection.
605 * @param connection the connection
606 * @param unique_name the unique name
607 * @returns #FALSE if not enough memory
610 dbus_bus_set_unique_name (DBusConnection *connection,
611 const char *unique_name)
615 _dbus_return_val_if_fail (connection != NULL, FALSE);
616 _dbus_return_val_if_fail (unique_name != NULL, FALSE);
618 bd = ensure_bus_data (connection);
622 _dbus_assert (bd->unique_name == NULL);
624 bd->unique_name = _dbus_strdup (unique_name);
625 return bd->unique_name != NULL;
629 * Gets the unique name of the connection. Only possible after the
630 * connection has been registered with the message bus.
632 * The name remains valid for the duration of the connection and
633 * should not be freed by the caller.
635 * @param connection the connection
636 * @returns the unique name or NULL on error
639 dbus_bus_get_unique_name (DBusConnection *connection)
643 _dbus_return_val_if_fail (connection != NULL, NULL);
645 bd = ensure_bus_data (connection);
649 return bd->unique_name;
653 * Asks the bus to return the uid of the named
656 * Not going to work on Windows, the bus should return
659 * @param connection the connection
660 * @param name a name owned by the connection
661 * @param error location to store the error
662 * @returns a result code, -1 if error is set
665 dbus_bus_get_unix_user (DBusConnection *connection,
669 DBusMessage *message, *reply;
672 _dbus_return_val_if_fail (connection != NULL, DBUS_UID_UNSET);
673 _dbus_return_val_if_fail (name != NULL, DBUS_UID_UNSET);
674 _dbus_return_val_if_fail (_dbus_check_is_valid_bus_name (name), DBUS_UID_UNSET);
675 _dbus_return_val_if_error_is_set (error, DBUS_UID_UNSET);
677 message = dbus_message_new_method_call (DBUS_SERVICE_DBUS,
680 "GetConnectionUnixUser");
684 _DBUS_SET_OOM (error);
685 return DBUS_UID_UNSET;
688 if (!dbus_message_append_args (message,
689 DBUS_TYPE_STRING, &name,
692 dbus_message_unref (message);
693 _DBUS_SET_OOM (error);
694 return DBUS_UID_UNSET;
697 reply = dbus_connection_send_with_reply_and_block (connection, message, -1,
700 dbus_message_unref (message);
704 _DBUS_ASSERT_ERROR_IS_SET (error);
705 return DBUS_UID_UNSET;
708 if (dbus_set_error_from_message (error, reply))
710 _DBUS_ASSERT_ERROR_IS_SET (error);
711 dbus_message_unref (reply);
712 return DBUS_UID_UNSET;
715 if (!dbus_message_get_args (reply, error,
716 DBUS_TYPE_UINT32, &uid,
719 _DBUS_ASSERT_ERROR_IS_SET (error);
720 dbus_message_unref (reply);
721 return DBUS_UID_UNSET;
724 dbus_message_unref (reply);
726 return (unsigned long) uid;
731 * Asks the bus to assign the given name to this connection by invoking
732 * the RequestName method on the bus. This method is fully documented
733 * in the D-Bus specification. For quick reference, the flags and
734 * result codes are discussed here, but the specification is the
735 * canonical version of this information.
737 * The #DBUS_NAME_FLAG_ALLOW_REPLACEMENT flag indicates that the caller
738 * will allow other services to take over the name from the current owner.
740 * The #DBUS_NAME_FLAG_REPLACE_EXISTING flag indicates that the caller
741 * would like to take over the name from the current owner.
742 * If the current name owner did not use #DBUS_NAME_FLAG_ALLOW_REPLACEMENT
743 * then this flag indicates that the caller would like to be placed
744 * in the queue to own the name when the current owner lets go.
746 * If no flags are given, an application will receive the requested
747 * name only if the name is currently unowned; it will NOT give
748 * up the name if another application asks to take it over using
749 * #DBUS_NAME_FLAG_REPLACE_EXISTING.
751 * This function returns a result code. The possible result codes
754 * #DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER means that the name had no
755 * existing owner, and the caller is now the primary owner; or that
756 * the name had an owner, and the caller specified
757 * #DBUS_NAME_FLAG_REPLACE_EXISTING, and the current owner
758 * specified #DBUS_NAME_FLAG_ALLOW_REPLACEMENT.
760 * #DBUS_REQUEST_NAME_REPLY_IN_QUEUE happens only if the caller does NOT
761 * specify #DBUS_NAME_FLAG_DO_NOT_QUEUE and either the current owner
762 * did NOT specify #DBUS_NAME_FLAG_ALLOW_REPLACEMENT or the caller did NOT
763 * specify #DBUS_NAME_FLAG_REPLACE_EXISTING. In this case the caller ends up
764 * in a queue to own the name after the current owner gives it up.
766 * #DBUS_REQUEST_NAME_REPLY_EXISTS happens if the name has an owner
767 * already and the caller specifies #DBUS_NAME_FLAG_DO_NOT_QUEUE
768 * and either the current owner has NOT specified
769 * #DBUS_NAME_FLAG_ALLOW_REPLACEMENT or the caller did NOT specify
770 * #DBUS_NAME_FLAG_REPLACE_EXISTING.
772 * #DBUS_REQUEST_NAME_REPLY_ALREADY_OWNER happens if an application
773 * requests a name it already owns.
775 * When a service represents an application, say "text editor," then
776 * it should specify #DBUS_NAME_FLAG_ALLOW_REPLACEMENT if it wants
777 * the last editor started to be the user's editor vs. the first one
778 * started. Then any editor that can be the user's editor should
779 * specify #DBUS_NAME_FLAG_REPLACE_EXISTING to either take over
780 * (last-started-wins) or be queued up (first-started-wins) according
781 * to whether #DBUS_NAME_FLAG_ALLOW_REPLACEMENT was given.
783 * @param connection the connection
784 * @param name the name to request
786 * @param error location to store the error
787 * @returns a result code, -1 if error is set
790 dbus_bus_request_name (DBusConnection *connection,
795 DBusMessage *message, *reply;
796 dbus_uint32_t result;
798 _dbus_return_val_if_fail (connection != NULL, 0);
799 _dbus_return_val_if_fail (name != NULL, 0);
800 _dbus_return_val_if_fail (_dbus_check_is_valid_bus_name (name), 0);
801 _dbus_return_val_if_error_is_set (error, 0);
803 message = dbus_message_new_method_call (DBUS_SERVICE_DBUS,
810 _DBUS_SET_OOM (error);
814 if (!dbus_message_append_args (message,
815 DBUS_TYPE_STRING, &name,
816 DBUS_TYPE_UINT32, &flags,
819 dbus_message_unref (message);
820 _DBUS_SET_OOM (error);
824 reply = dbus_connection_send_with_reply_and_block (connection, message, -1,
827 dbus_message_unref (message);
831 _DBUS_ASSERT_ERROR_IS_SET (error);
835 if (dbus_set_error_from_message (error, reply))
837 _DBUS_ASSERT_ERROR_IS_SET (error);
838 dbus_message_unref (reply);
842 if (!dbus_message_get_args (reply, error,
843 DBUS_TYPE_UINT32, &result,
846 _DBUS_ASSERT_ERROR_IS_SET (error);
847 dbus_message_unref (reply);
851 dbus_message_unref (reply);
858 * Asks the bus to unassign the given name to this connection by invoking
859 * the ReleaseName method on the bus. This method is fully documented
860 * in the D-Bus specification.
862 * @param connection the connection
863 * @param name the name to remove
864 * @param error location to store the error
865 * @returns a result code, -1 if error is set
868 dbus_bus_release_name (DBusConnection *connection,
872 DBusMessage *message, *reply;
873 dbus_uint32_t result;
875 _dbus_return_val_if_fail (connection != NULL, 0);
876 _dbus_return_val_if_fail (name != NULL, 0);
877 _dbus_return_val_if_fail (_dbus_check_is_valid_bus_name (name), 0);
878 _dbus_return_val_if_error_is_set (error, 0);
880 message = dbus_message_new_method_call (DBUS_SERVICE_DBUS,
887 _DBUS_SET_OOM (error);
891 if (!dbus_message_append_args (message,
892 DBUS_TYPE_STRING, &name,
895 dbus_message_unref (message);
896 _DBUS_SET_OOM (error);
900 reply = dbus_connection_send_with_reply_and_block (connection, message, -1,
903 dbus_message_unref (message);
907 _DBUS_ASSERT_ERROR_IS_SET (error);
911 if (dbus_set_error_from_message (error, reply))
913 _DBUS_ASSERT_ERROR_IS_SET (error);
914 dbus_message_unref (reply);
918 if (!dbus_message_get_args (reply, error,
919 DBUS_TYPE_UINT32, &result,
922 _DBUS_ASSERT_ERROR_IS_SET (error);
923 dbus_message_unref (reply);
927 dbus_message_unref (reply);
933 * Checks whether a certain name has an owner.
935 * @param connection the connection
936 * @param name the name
937 * @param error location to store any errors
938 * @returns #TRUE if the name exists, #FALSE if not or on error
941 dbus_bus_name_has_owner (DBusConnection *connection,
945 DBusMessage *message, *reply;
948 _dbus_return_val_if_fail (connection != NULL, FALSE);
949 _dbus_return_val_if_fail (name != NULL, FALSE);
950 _dbus_return_val_if_fail (_dbus_check_is_valid_bus_name (name), FALSE);
951 _dbus_return_val_if_error_is_set (error, FALSE);
953 message = dbus_message_new_method_call (DBUS_SERVICE_DBUS,
959 _DBUS_SET_OOM (error);
963 if (!dbus_message_append_args (message,
964 DBUS_TYPE_STRING, &name,
967 dbus_message_unref (message);
968 _DBUS_SET_OOM (error);
972 reply = dbus_connection_send_with_reply_and_block (connection, message, -1, error);
973 dbus_message_unref (message);
977 _DBUS_ASSERT_ERROR_IS_SET (error);
981 if (!dbus_message_get_args (reply, error,
982 DBUS_TYPE_BOOLEAN, &exists,
985 _DBUS_ASSERT_ERROR_IS_SET (error);
986 dbus_message_unref (reply);
990 dbus_message_unref (reply);
995 * Starts a service that will request ownership of the given name.
996 * The returned result will be one of be one of
997 * #DBUS_START_REPLY_SUCCESS or #DBUS_START_REPLY_ALREADY_RUNNING if
998 * successful. Pass #NULL if you don't care about the result.
1000 * The flags parameter is for future expansion, currently you should
1003 * @param connection the connection
1004 * @param name the name we want the new service to request
1005 * @param flags the flags (should always be 0 for now)
1006 * @param result a place to store the result or #NULL
1007 * @param error location to store any errors
1008 * @returns #TRUE if the activation succeeded, #FALSE if not
1011 dbus_bus_start_service_by_name (DBusConnection *connection,
1013 dbus_uint32_t flags,
1014 dbus_uint32_t *result,
1020 _dbus_return_val_if_fail (connection != NULL, FALSE);
1021 _dbus_return_val_if_fail (_dbus_check_is_valid_bus_name (name), FALSE);
1023 msg = dbus_message_new_method_call (DBUS_SERVICE_DBUS,
1025 DBUS_INTERFACE_DBUS,
1026 "StartServiceByName");
1028 if (!dbus_message_append_args (msg, DBUS_TYPE_STRING, &name,
1029 DBUS_TYPE_UINT32, &flags, DBUS_TYPE_INVALID))
1031 dbus_message_unref (msg);
1032 _DBUS_SET_OOM (error);
1036 reply = dbus_connection_send_with_reply_and_block (connection, msg,
1038 dbus_message_unref (msg);
1042 _DBUS_ASSERT_ERROR_IS_SET (error);
1046 if (dbus_set_error_from_message (error, reply))
1048 _DBUS_ASSERT_ERROR_IS_SET (error);
1049 dbus_message_unref (reply);
1053 if (result != NULL &&
1054 !dbus_message_get_args (reply, error, DBUS_TYPE_UINT32,
1055 result, DBUS_TYPE_INVALID))
1057 _DBUS_ASSERT_ERROR_IS_SET (error);
1058 dbus_message_unref (reply);
1062 dbus_message_unref (reply);
1067 send_no_return_values (DBusConnection *connection,
1073 /* Block to check success codepath */
1076 reply = dbus_connection_send_with_reply_and_block (connection, msg,
1080 _DBUS_ASSERT_ERROR_IS_SET (error);
1082 dbus_message_unref (reply);
1086 /* Silently-fail nonblocking codepath */
1087 dbus_message_set_no_reply (msg, TRUE);
1088 dbus_connection_send (connection, msg, NULL);
1093 * Adds a match rule to match messages going through the message bus.
1094 * The "rule" argument is the string form of a match rule.
1096 * If you pass #NULL for the error, this function will not
1097 * block; the match thus won't be added until you flush the
1098 * connection, and if there's an error adding the match
1099 * (only possible error is lack of resources in the bus),
1100 * you won't find out about it.
1102 * If you pass non-#NULL for the error this function will
1103 * block until it gets a reply.
1105 * Normal API conventions would have the function return
1106 * a boolean value indicating whether the error was set,
1107 * but that would require blocking always to determine
1110 * The AddMatch method is fully documented in the D-Bus
1111 * specification. For quick reference, the format of the
1112 * match rules is discussed here, but the specification
1113 * is the canonical version of this information.
1115 * Rules are specified as a string of comma separated
1116 * key/value pairs. An example is
1117 * "type='signal',sender='org.freedesktop.DBus',
1118 * interface='org.freedesktop.DBus',member='Foo',
1119 * path='/bar/foo',destination=':452345.34'"
1121 * Possible keys you can match on are type, sender,
1122 * interface, member, path, destination and the special
1123 * arg keys. Excluding a key from the rule indicates
1124 * a wildcard match. For instance excluding the
1125 * the member from a match rule but adding a sender would
1126 * let all messages from that sender through.
1128 * Matches are inclusive not exclusive so as long as one
1129 * rule matches the message will get through. It is important
1130 * to note this because every time a message is received the
1131 * application will be paged into memory to process it. This
1132 * can cause performance problems such as draining batteries
1133 * on embedded platforms.
1135 * The special arg keys are used for further restricting the
1136 * match based on the parameters sent by the signal or method.
1137 * For instance arg1='foo' will check the first argument,
1138 * arg2='bar' the second and so on. For performance reasons
1139 * there is a set limit on the highest number parameter that
1140 * can be checked which is set in dbus-protocol.h
1142 * @param connection connection to the message bus
1143 * @param rule textual form of match rule
1144 * @param error location to store any errors
1147 dbus_bus_add_match (DBusConnection *connection,
1153 _dbus_return_if_fail (rule != NULL);
1155 msg = dbus_message_new_method_call (DBUS_SERVICE_DBUS,
1157 DBUS_INTERFACE_DBUS,
1162 _DBUS_SET_OOM (error);
1166 if (!dbus_message_append_args (msg, DBUS_TYPE_STRING, &rule,
1169 dbus_message_unref (msg);
1170 _DBUS_SET_OOM (error);
1174 send_no_return_values (connection, msg, error);
1176 dbus_message_unref (msg);
1180 * Removes a previously-added match rule "by value" (the most
1181 * recently-added identical rule gets removed). The "rule" argument
1182 * is the string form of a match rule.
1184 * If you pass #NULL for the error, this function will not
1185 * block; otherwise it will. See detailed explanation in
1186 * docs for dbus_bus_add_match().
1188 * @param connection connection to the message bus
1189 * @param rule textual form of match rule
1190 * @param error location to store any errors
1193 dbus_bus_remove_match (DBusConnection *connection,
1199 _dbus_return_if_fail (rule != NULL);
1201 msg = dbus_message_new_method_call (DBUS_SERVICE_DBUS,
1203 DBUS_INTERFACE_DBUS,
1206 if (!dbus_message_append_args (msg, DBUS_TYPE_STRING, &rule,
1209 dbus_message_unref (msg);
1210 _DBUS_SET_OOM (error);
1214 send_no_return_values (connection, msg, error);
1216 dbus_message_unref (msg);