1 /* -*- mode: C; c-file-style: "gnu" -*- */
2 /* dbus-connection.c DBusConnection object
4 * Copyright (C) 2002, 2003 Red Hat Inc.
6 * Licensed under the Academic Free License version 1.2
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 #include "dbus-connection.h"
26 #include "dbus-list.h"
27 #include "dbus-timeout.h"
28 #include "dbus-transport.h"
29 #include "dbus-watch.h"
30 #include "dbus-connection-internal.h"
31 #include "dbus-list.h"
32 #include "dbus-hash.h"
33 #include "dbus-message-internal.h"
34 #include "dbus-message-handler.h"
35 #include "dbus-threads.h"
36 #include "dbus-protocol.h"
37 #include "dbus-dataslot.h"
38 #include "dbus-object-registry.h"
41 #define CONNECTION_LOCK(connection) do { \
42 _dbus_verbose (" LOCK: %s\n", _DBUS_FUNCTION_NAME); \
43 dbus_mutex_lock ((connection)->mutex); \
45 #define CONNECTION_UNLOCK(connection) do { \
46 _dbus_verbose (" UNLOCK: %s\n", _DBUS_FUNCTION_NAME); \
47 dbus_mutex_unlock ((connection)->mutex); \
50 #define CONNECTION_LOCK(connection) dbus_mutex_lock ((connection)->mutex)
51 #define CONNECTION_UNLOCK(connection) dbus_mutex_unlock ((connection)->mutex)
55 * @defgroup DBusConnection DBusConnection
57 * @brief Connection to another application
59 * A DBusConnection represents a connection to another
60 * application. Messages can be sent and received via this connection.
61 * The other application may be a message bus; for convenience, the
62 * function dbus_bus_get() is provided to automatically open a
63 * connection to the well-known message buses.
65 * In brief a DBusConnection is a message queue associated with some
66 * message transport mechanism such as a socket. The connection
67 * maintains a queue of incoming messages and a queue of outgoing
70 * Incoming messages are normally processed by calling
71 * dbus_connection_dispatch(). dbus_connection_dispatch() runs any
72 * handlers registered for the topmost message in the message queue,
73 * then discards the message, then returns.
75 * dbus_connection_get_dispatch_status() indicates whether
76 * messages are currently in the queue that need dispatching.
77 * dbus_connection_set_dispatch_status_function() allows
78 * you to set a function to be used to monitor the dispatch status.
80 * If you're using GLib or Qt add-on libraries for D-BUS, there are
81 * special convenience APIs in those libraries that hide
82 * all the details of dispatch and watch/timeout monitoring.
83 * For example, dbus_connection_setup_with_g_main().
85 * If you aren't using these add-on libraries, you have to manually
86 * call dbus_connection_set_dispatch_status_function(),
87 * dbus_connection_set_watch_functions(),
88 * dbus_connection_set_timeout_functions() providing appropriate
89 * functions to integrate the connection with your application's main
92 * When you use dbus_connection_send() or one of its variants to send
93 * a message, the message is added to the outgoing queue. It's
94 * actually written to the network later; either in
95 * dbus_watch_handle() invoked by your main loop, or in
96 * dbus_connection_flush() which blocks until it can write out the
97 * entire outgoing queue. The GLib/Qt add-on libraries again
98 * handle the details here for you by setting up watch functions.
100 * When a connection is disconnected, you are guaranteed to get a
101 * message with the name #DBUS_MESSAGE_LOCAL_DISCONNECT.
103 * You may not drop the last reference to a #DBusConnection
104 * until that connection has been disconnected.
106 * You may dispatch the unprocessed incoming message queue even if the
107 * connection is disconnected. However, #DBUS_MESSAGE_LOCAL_DISCONNECT
108 * will always be the last message in the queue (obviously no messages
109 * are received after disconnection).
111 * #DBusConnection has thread locks and drops them when invoking user
112 * callbacks, so in general is transparently threadsafe. However,
113 * #DBusMessage does NOT have thread locks; you must not send the same
114 * message to multiple #DBusConnection that will be used from
119 * @defgroup DBusConnectionInternals DBusConnection implementation details
120 * @ingroup DBusInternals
121 * @brief Implementation details of DBusConnection
126 /** default timeout value when waiting for a message reply */
127 #define DEFAULT_TIMEOUT_VALUE (15 * 1000)
129 static dbus_bool_t _dbus_modify_sigpipe = TRUE;
132 * Implementation details of DBusConnection. All fields are private.
134 struct DBusConnection
136 DBusAtomic refcount; /**< Reference count. */
138 DBusMutex *mutex; /**< Lock on the entire DBusConnection */
140 dbus_bool_t dispatch_acquired; /**< Protects dispatch() */
141 DBusCondVar *dispatch_cond; /**< Protects dispatch() */
143 dbus_bool_t io_path_acquired; /**< Protects transport io path */
144 DBusCondVar *io_path_cond; /**< Protects transport io path */
146 DBusList *outgoing_messages; /**< Queue of messages we need to send, send the end of the list first. */
147 DBusList *incoming_messages; /**< Queue of messages we have received, end of the list received most recently. */
149 DBusMessage *message_borrowed; /**< True if the first incoming message has been borrowed */
150 DBusCondVar *message_returned_cond; /**< Used with dbus_connection_borrow_message() */
152 int n_outgoing; /**< Length of outgoing queue. */
153 int n_incoming; /**< Length of incoming queue. */
155 DBusCounter *outgoing_counter; /**< Counts size of outgoing messages. */
157 DBusTransport *transport; /**< Object that sends/receives messages over network. */
158 DBusWatchList *watches; /**< Stores active watches. */
159 DBusTimeoutList *timeouts; /**< Stores active timeouts. */
161 DBusList *filter_list; /**< List of filters. */
163 DBusDataSlotList slot_list; /**< Data stored by allocated integer ID */
165 DBusHashTable *pending_replies; /**< Hash of message serials and their message handlers. */
167 dbus_uint32_t client_serial; /**< Client serial. Increments each time a message is sent */
168 DBusList *disconnect_message_link; /**< Preallocated list node for queueing the disconnection message */
170 DBusWakeupMainFunction wakeup_main_function; /**< Function to wake up the mainloop */
171 void *wakeup_main_data; /**< Application data for wakeup_main_function */
172 DBusFreeFunction free_wakeup_main_data; /**< free wakeup_main_data */
174 DBusDispatchStatusFunction dispatch_status_function; /**< Function on dispatch status changes */
175 void *dispatch_status_data; /**< Application data for dispatch_status_function */
176 DBusFreeFunction free_dispatch_status_data; /**< free dispatch_status_data */
178 DBusDispatchStatus last_dispatch_status; /**< The last dispatch status we reported to the application. */
180 DBusList *link_cache; /**< A cache of linked list links to prevent contention
181 * for the global linked list mempool lock
183 DBusObjectRegistry *objects; /**< Objects registered with this connection */
188 DBusConnection *connection;
189 DBusMessageHandler *handler;
190 DBusTimeout *timeout;
193 DBusList *timeout_link; /* Preallocated timeout response */
195 dbus_bool_t timeout_added;
196 dbus_bool_t connection_added;
199 static void reply_handler_data_free (ReplyHandlerData *data);
201 static void _dbus_connection_remove_timeout_locked (DBusConnection *connection,
202 DBusTimeout *timeout);
203 static DBusDispatchStatus _dbus_connection_get_dispatch_status_unlocked (DBusConnection *connection);
204 static void _dbus_connection_update_dispatch_status_and_unlock (DBusConnection *connection,
205 DBusDispatchStatus new_status);
206 static void _dbus_connection_last_unref (DBusConnection *connection);
210 * Acquires the connection lock.
212 * @param connection the connection.
215 _dbus_connection_lock (DBusConnection *connection)
217 CONNECTION_LOCK (connection);
221 * Releases the connection lock.
223 * @param connection the connection.
226 _dbus_connection_unlock (DBusConnection *connection)
228 CONNECTION_UNLOCK (connection);
232 * Wakes up the main loop if it is sleeping
233 * Needed if we're e.g. queueing outgoing messages
234 * on a thread while the mainloop sleeps.
236 * @param connection the connection.
239 _dbus_connection_wakeup_mainloop (DBusConnection *connection)
241 if (connection->wakeup_main_function)
242 (*connection->wakeup_main_function) (connection->wakeup_main_data);
245 #ifdef DBUS_BUILD_TESTS
246 /* For now this function isn't used */
248 * Adds a message to the incoming message queue, returning #FALSE
249 * if there's insufficient memory to queue the message.
250 * Does not take over refcount of the message.
252 * @param connection the connection.
253 * @param message the message to queue.
254 * @returns #TRUE on success.
257 _dbus_connection_queue_received_message (DBusConnection *connection,
258 DBusMessage *message)
262 link = _dbus_list_alloc_link (message);
266 dbus_message_ref (message);
267 _dbus_connection_queue_received_message_link (connection, link);
274 * Adds a message-containing list link to the incoming message queue,
275 * taking ownership of the link and the message's current refcount.
276 * Cannot fail due to lack of memory.
278 * @param connection the connection.
279 * @param link the message link to queue.
282 _dbus_connection_queue_received_message_link (DBusConnection *connection,
285 ReplyHandlerData *reply_handler_data;
286 dbus_int32_t reply_serial;
287 DBusMessage *message;
289 _dbus_assert (_dbus_transport_get_is_authenticated (connection->transport));
291 _dbus_list_append_link (&connection->incoming_messages,
293 message = link->data;
295 /* If this is a reply we're waiting on, remove timeout for it */
296 reply_serial = dbus_message_get_reply_serial (message);
297 if (reply_serial != -1)
299 reply_handler_data = _dbus_hash_table_lookup_int (connection->pending_replies,
301 if (reply_handler_data != NULL)
303 if (reply_handler_data->timeout_added)
304 _dbus_connection_remove_timeout_locked (connection,
305 reply_handler_data->timeout);
306 reply_handler_data->timeout_added = FALSE;
310 connection->n_incoming += 1;
312 _dbus_connection_wakeup_mainloop (connection);
314 _dbus_assert (dbus_message_get_name (message) != NULL);
315 _dbus_verbose ("Message %p (%s) added to incoming queue %p, %d incoming\n",
316 message, dbus_message_get_name (message),
318 connection->n_incoming);
322 * Adds a link + message to the incoming message queue.
323 * Can't fail. Takes ownership of both link and message.
325 * @param connection the connection.
326 * @param link the list node and message to queue.
328 * @todo This needs to wake up the mainloop if it is in
329 * a poll/select and this is a multithreaded app.
332 _dbus_connection_queue_synthesized_message_link (DBusConnection *connection,
335 _dbus_list_append_link (&connection->incoming_messages, link);
337 connection->n_incoming += 1;
339 _dbus_connection_wakeup_mainloop (connection);
341 _dbus_verbose ("Synthesized message %p added to incoming queue %p, %d incoming\n",
342 link->data, connection, connection->n_incoming);
347 * Checks whether there are messages in the outgoing message queue.
349 * @param connection the connection.
350 * @returns #TRUE if the outgoing queue is non-empty.
353 _dbus_connection_have_messages_to_send (DBusConnection *connection)
355 return connection->outgoing_messages != NULL;
359 * Gets the next outgoing message. The message remains in the
360 * queue, and the caller does not own a reference to it.
362 * @param connection the connection.
363 * @returns the message to be sent.
366 _dbus_connection_get_message_to_send (DBusConnection *connection)
368 return _dbus_list_get_last (&connection->outgoing_messages);
372 * Notifies the connection that a message has been sent, so the
373 * message can be removed from the outgoing queue.
374 * Called with the connection lock held.
376 * @param connection the connection.
377 * @param message the message that was sent.
380 _dbus_connection_message_sent (DBusConnection *connection,
381 DBusMessage *message)
385 _dbus_assert (_dbus_transport_get_is_authenticated (connection->transport));
387 link = _dbus_list_get_last_link (&connection->outgoing_messages);
388 _dbus_assert (link != NULL);
389 _dbus_assert (link->data == message);
391 /* Save this link in the link cache */
392 _dbus_list_unlink (&connection->outgoing_messages,
394 _dbus_list_prepend_link (&connection->link_cache, link);
396 connection->n_outgoing -= 1;
398 _dbus_verbose ("Message %p (%s) removed from outgoing queue %p, %d left to send\n",
399 message, dbus_message_get_name (message),
400 connection, connection->n_outgoing);
402 /* Save this link in the link cache also */
403 _dbus_message_remove_size_counter (message, connection->outgoing_counter,
405 _dbus_list_prepend_link (&connection->link_cache, link);
407 dbus_message_unref (message);
409 if (connection->n_outgoing == 0)
410 _dbus_transport_messages_pending (connection->transport,
411 connection->n_outgoing);
415 * Adds a watch using the connection's DBusAddWatchFunction if
416 * available. Otherwise records the watch to be added when said
417 * function is available. Also re-adds the watch if the
418 * DBusAddWatchFunction changes. May fail due to lack of memory.
420 * @param connection the connection.
421 * @param watch the watch to add.
422 * @returns #TRUE on success.
425 _dbus_connection_add_watch (DBusConnection *connection,
428 if (connection->watches) /* null during finalize */
429 return _dbus_watch_list_add_watch (connection->watches,
436 * Removes a watch using the connection's DBusRemoveWatchFunction
437 * if available. It's an error to call this function on a watch
438 * that was not previously added.
440 * @param connection the connection.
441 * @param watch the watch to remove.
444 _dbus_connection_remove_watch (DBusConnection *connection,
447 if (connection->watches) /* null during finalize */
448 _dbus_watch_list_remove_watch (connection->watches,
453 * Toggles a watch and notifies app via connection's
454 * DBusWatchToggledFunction if available. It's an error to call this
455 * function on a watch that was not previously added.
457 * @param connection the connection.
458 * @param watch the watch to toggle.
459 * @param enabled whether to enable or disable
462 _dbus_connection_toggle_watch (DBusConnection *connection,
466 if (connection->watches) /* null during finalize */
467 _dbus_watch_list_toggle_watch (connection->watches,
472 * Adds a timeout using the connection's DBusAddTimeoutFunction if
473 * available. Otherwise records the timeout to be added when said
474 * function is available. Also re-adds the timeout if the
475 * DBusAddTimeoutFunction changes. May fail due to lack of memory.
476 * The timeout will fire repeatedly until removed.
478 * @param connection the connection.
479 * @param timeout the timeout to add.
480 * @returns #TRUE on success.
483 _dbus_connection_add_timeout (DBusConnection *connection,
484 DBusTimeout *timeout)
486 if (connection->timeouts) /* null during finalize */
487 return _dbus_timeout_list_add_timeout (connection->timeouts,
494 * Removes a timeout using the connection's DBusRemoveTimeoutFunction
495 * if available. It's an error to call this function on a timeout
496 * that was not previously added.
498 * @param connection the connection.
499 * @param timeout the timeout to remove.
502 _dbus_connection_remove_timeout (DBusConnection *connection,
503 DBusTimeout *timeout)
505 if (connection->timeouts) /* null during finalize */
506 _dbus_timeout_list_remove_timeout (connection->timeouts,
511 _dbus_connection_remove_timeout_locked (DBusConnection *connection,
512 DBusTimeout *timeout)
514 CONNECTION_LOCK (connection);
515 _dbus_connection_remove_timeout (connection, timeout);
516 CONNECTION_UNLOCK (connection);
520 * Toggles a timeout and notifies app via connection's
521 * DBusTimeoutToggledFunction if available. It's an error to call this
522 * function on a timeout that was not previously added.
524 * @param connection the connection.
525 * @param timeout the timeout to toggle.
526 * @param enabled whether to enable or disable
529 _dbus_connection_toggle_timeout (DBusConnection *connection,
530 DBusTimeout *timeout,
533 if (connection->timeouts) /* null during finalize */
534 _dbus_timeout_list_toggle_timeout (connection->timeouts,
539 * Tells the connection that the transport has been disconnected.
540 * Results in posting a disconnect message on the incoming message
541 * queue. Only has an effect the first time it's called.
543 * @param connection the connection
546 _dbus_connection_notify_disconnected (DBusConnection *connection)
548 if (connection->disconnect_message_link)
550 /* We haven't sent the disconnect message already */
551 _dbus_connection_queue_synthesized_message_link (connection,
552 connection->disconnect_message_link);
553 connection->disconnect_message_link = NULL;
559 * Acquire the transporter I/O path. This must be done before
560 * doing any I/O in the transporter. May sleep and drop the
561 * connection mutex while waiting for the I/O path.
563 * @param connection the connection.
564 * @param timeout_milliseconds maximum blocking time, or -1 for no limit.
565 * @returns TRUE if the I/O path was acquired.
568 _dbus_connection_acquire_io_path (DBusConnection *connection,
569 int timeout_milliseconds)
571 dbus_bool_t res = TRUE;
573 if (connection->io_path_acquired)
575 if (timeout_milliseconds != -1)
576 res = dbus_condvar_wait_timeout (connection->io_path_cond,
578 timeout_milliseconds);
580 dbus_condvar_wait (connection->io_path_cond, connection->mutex);
585 _dbus_assert (!connection->io_path_acquired);
587 connection->io_path_acquired = TRUE;
594 * Release the I/O path when you're done with it. Only call
595 * after you've acquired the I/O. Wakes up at most one thread
596 * currently waiting to acquire the I/O path.
598 * @param connection the connection.
601 _dbus_connection_release_io_path (DBusConnection *connection)
603 _dbus_assert (connection->io_path_acquired);
605 connection->io_path_acquired = FALSE;
606 dbus_condvar_wake_one (connection->io_path_cond);
611 * Queues incoming messages and sends outgoing messages for this
612 * connection, optionally blocking in the process. Each call to
613 * _dbus_connection_do_iteration() will call select() or poll() one
614 * time and then read or write data if possible.
616 * The purpose of this function is to be able to flush outgoing
617 * messages or queue up incoming messages without returning
618 * control to the application and causing reentrancy weirdness.
620 * The flags parameter allows you to specify whether to
621 * read incoming messages, write outgoing messages, or both,
622 * and whether to block if no immediate action is possible.
624 * The timeout_milliseconds parameter does nothing unless the
625 * iteration is blocking.
627 * If there are no outgoing messages and DBUS_ITERATION_DO_READING
628 * wasn't specified, then it's impossible to block, even if
629 * you specify DBUS_ITERATION_BLOCK; in that case the function
630 * returns immediately.
632 * @param connection the connection.
633 * @param flags iteration flags.
634 * @param timeout_milliseconds maximum blocking time, or -1 for no limit.
637 _dbus_connection_do_iteration (DBusConnection *connection,
639 int timeout_milliseconds)
641 if (connection->n_outgoing == 0)
642 flags &= ~DBUS_ITERATION_DO_WRITING;
644 if (_dbus_connection_acquire_io_path (connection,
645 (flags & DBUS_ITERATION_BLOCK) ? timeout_milliseconds : 0))
647 _dbus_transport_do_iteration (connection->transport,
648 flags, timeout_milliseconds);
649 _dbus_connection_release_io_path (connection);
654 * Creates a new connection for the given transport. A transport
655 * represents a message stream that uses some concrete mechanism, such
656 * as UNIX domain sockets. May return #NULL if insufficient
657 * memory exists to create the connection.
659 * @param transport the transport.
660 * @returns the new connection, or #NULL on failure.
663 _dbus_connection_new_for_transport (DBusTransport *transport)
665 DBusConnection *connection;
666 DBusWatchList *watch_list;
667 DBusTimeoutList *timeout_list;
668 DBusHashTable *pending_replies;
670 DBusCondVar *message_returned_cond;
671 DBusCondVar *dispatch_cond;
672 DBusCondVar *io_path_cond;
673 DBusList *disconnect_link;
674 DBusMessage *disconnect_message;
675 DBusCounter *outgoing_counter;
676 DBusObjectRegistry *objects;
680 pending_replies = NULL;
683 message_returned_cond = NULL;
684 dispatch_cond = NULL;
686 disconnect_link = NULL;
687 disconnect_message = NULL;
688 outgoing_counter = NULL;
691 watch_list = _dbus_watch_list_new ();
692 if (watch_list == NULL)
695 timeout_list = _dbus_timeout_list_new ();
696 if (timeout_list == NULL)
700 _dbus_hash_table_new (DBUS_HASH_INT,
701 NULL, (DBusFreeFunction)reply_handler_data_free);
702 if (pending_replies == NULL)
705 connection = dbus_new0 (DBusConnection, 1);
706 if (connection == NULL)
709 mutex = dbus_mutex_new ();
713 message_returned_cond = dbus_condvar_new ();
714 if (message_returned_cond == NULL)
717 dispatch_cond = dbus_condvar_new ();
718 if (dispatch_cond == NULL)
721 io_path_cond = dbus_condvar_new ();
722 if (io_path_cond == NULL)
725 disconnect_message = dbus_message_new_signal (DBUS_MESSAGE_LOCAL_DISCONNECT);
726 if (disconnect_message == NULL)
729 disconnect_link = _dbus_list_alloc_link (disconnect_message);
730 if (disconnect_link == NULL)
733 outgoing_counter = _dbus_counter_new ();
734 if (outgoing_counter == NULL)
737 objects = _dbus_object_registry_new (connection);
741 if (_dbus_modify_sigpipe)
742 _dbus_disable_sigpipe ();
744 connection->refcount.value = 1;
745 connection->mutex = mutex;
746 connection->dispatch_cond = dispatch_cond;
747 connection->io_path_cond = io_path_cond;
748 connection->message_returned_cond = message_returned_cond;
749 connection->transport = transport;
750 connection->watches = watch_list;
751 connection->timeouts = timeout_list;
752 connection->pending_replies = pending_replies;
753 connection->outgoing_counter = outgoing_counter;
754 connection->filter_list = NULL;
755 connection->last_dispatch_status = DBUS_DISPATCH_COMPLETE; /* so we're notified first time there's data */
756 connection->objects = objects;
758 _dbus_data_slot_list_init (&connection->slot_list);
760 connection->client_serial = 1;
762 connection->disconnect_message_link = disconnect_link;
764 if (!_dbus_transport_set_connection (transport, connection))
767 _dbus_transport_ref (transport);
772 if (disconnect_message != NULL)
773 dbus_message_unref (disconnect_message);
775 if (disconnect_link != NULL)
776 _dbus_list_free_link (disconnect_link);
778 if (io_path_cond != NULL)
779 dbus_condvar_free (io_path_cond);
781 if (dispatch_cond != NULL)
782 dbus_condvar_free (dispatch_cond);
784 if (message_returned_cond != NULL)
785 dbus_condvar_free (message_returned_cond);
788 dbus_mutex_free (mutex);
790 if (connection != NULL)
791 dbus_free (connection);
794 _dbus_hash_table_unref (pending_replies);
797 _dbus_watch_list_free (watch_list);
800 _dbus_timeout_list_free (timeout_list);
802 if (outgoing_counter)
803 _dbus_counter_unref (outgoing_counter);
806 _dbus_object_registry_unref (objects);
812 * Increments the reference count of a DBusConnection.
813 * Requires that the caller already holds the connection lock.
815 * @param connection the connection.
818 _dbus_connection_ref_unlocked (DBusConnection *connection)
820 #ifdef DBUS_HAVE_ATOMIC_INT
821 _dbus_atomic_inc (&connection->refcount);
823 _dbus_assert (connection->refcount.value > 0);
824 connection->refcount.value += 1;
829 * Decrements the reference count of a DBusConnection.
830 * Requires that the caller already holds the connection lock.
832 * @param connection the connection.
835 _dbus_connection_unref_unlocked (DBusConnection *connection)
837 dbus_bool_t last_unref;
839 _dbus_return_if_fail (connection != NULL);
841 /* The connection lock is better than the global
842 * lock in the atomic increment fallback
845 #ifdef DBUS_HAVE_ATOMIC_INT
846 last_unref = (_dbus_atomic_dec (&connection->refcount) == 1);
848 _dbus_assert (connection->refcount.value > 0);
850 connection->refcount.value -= 1;
851 last_unref = (connection->refcount.value == 0);
853 printf ("unref_unlocked() connection %p count = %d\n", connection, connection->refcount.value);
858 _dbus_connection_last_unref (connection);
862 _dbus_connection_get_next_client_serial (DBusConnection *connection)
866 serial = connection->client_serial++;
868 if (connection->client_serial < 0)
869 connection->client_serial = 1;
875 * Used to notify a connection when a DBusMessageHandler is
876 * destroyed, so the connection can drop any reference
877 * to the handler. This is a private function, but still
878 * takes the connection lock. Don't call it with the lock held.
880 * @todo needs to check in pending_replies too.
882 * @param connection the connection
883 * @param handler the handler
886 _dbus_connection_handler_destroyed_locked (DBusConnection *connection,
887 DBusMessageHandler *handler)
891 CONNECTION_LOCK (connection);
893 link = _dbus_list_get_first_link (&connection->filter_list);
896 DBusMessageHandler *h = link->data;
897 DBusList *next = _dbus_list_get_next_link (&connection->filter_list, link);
900 _dbus_list_remove_link (&connection->filter_list,
905 CONNECTION_UNLOCK (connection);
909 * A callback for use with dbus_watch_new() to create a DBusWatch.
911 * @todo This is basically a hack - we could delete _dbus_transport_handle_watch()
912 * and the virtual handle_watch in DBusTransport if we got rid of it.
913 * The reason this is some work is threading, see the _dbus_connection_handle_watch()
916 * @param watch the watch.
917 * @param condition the current condition of the file descriptors being watched.
918 * @param data must be a pointer to a #DBusConnection
919 * @returns #FALSE if the IO condition may not have been fully handled due to lack of memory
922 _dbus_connection_handle_watch (DBusWatch *watch,
923 unsigned int condition,
926 DBusConnection *connection;
928 DBusDispatchStatus status;
932 CONNECTION_LOCK (connection);
933 _dbus_connection_acquire_io_path (connection, -1);
934 retval = _dbus_transport_handle_watch (connection->transport,
936 _dbus_connection_release_io_path (connection);
938 status = _dbus_connection_get_dispatch_status_unlocked (connection);
940 /* this calls out to user code */
941 _dbus_connection_update_dispatch_status_and_unlock (connection, status);
947 * Get the server ID to be used in the object ID for an object
948 * registered with this connection.
950 * @todo implement this function
952 * @param connection the connection.
953 * @returns the portion of the object ID
956 _dbus_connection_init_id (DBusConnection *connection,
957 DBusObjectID *object_id)
960 dbus_object_id_set_server_bits (object_id, 15);
961 dbus_object_id_set_client_bits (object_id, 31);
962 dbus_object_id_set_is_server_bit (object_id, FALSE);
968 * @addtogroup DBusConnection
974 * Opens a new connection to a remote address.
976 * @todo specify what the address parameter is. Right now
977 * it's just the name of a UNIX domain socket. It should be
978 * something more complex that encodes which transport to use.
980 * If the open fails, the function returns #NULL, and provides
981 * a reason for the failure in the result parameter. Pass
982 * #NULL for the result parameter if you aren't interested
983 * in the reason for failure.
985 * @param address the address.
986 * @param error address where an error can be returned.
987 * @returns new connection, or #NULL on failure.
990 dbus_connection_open (const char *address,
993 DBusConnection *connection;
994 DBusTransport *transport;
996 _dbus_return_val_if_fail (address != NULL, NULL);
997 _dbus_return_val_if_error_is_set (error, NULL);
999 transport = _dbus_transport_open (address, error);
1000 if (transport == NULL)
1002 _DBUS_ASSERT_ERROR_IS_SET (error);
1006 connection = _dbus_connection_new_for_transport (transport);
1008 _dbus_transport_unref (transport);
1010 if (connection == NULL)
1012 dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
1020 * Increments the reference count of a DBusConnection.
1022 * @param connection the connection.
1025 dbus_connection_ref (DBusConnection *connection)
1027 _dbus_return_if_fail (connection != NULL);
1029 /* The connection lock is better than the global
1030 * lock in the atomic increment fallback
1033 #ifdef DBUS_HAVE_ATOMIC_INT
1034 _dbus_atomic_inc (&connection->refcount);
1036 CONNECTION_LOCK (connection);
1037 _dbus_assert (connection->refcount.value > 0);
1039 connection->refcount.value += 1;
1040 CONNECTION_UNLOCK (connection);
1045 free_outgoing_message (void *element,
1048 DBusMessage *message = element;
1049 DBusConnection *connection = data;
1051 _dbus_message_remove_size_counter (message,
1052 connection->outgoing_counter,
1054 dbus_message_unref (message);
1057 /* This is run without the mutex held, but after the last reference
1058 * to the connection has been dropped we should have no thread-related
1062 _dbus_connection_last_unref (DBusConnection *connection)
1066 _dbus_verbose ("Finalizing connection %p\n", connection);
1068 _dbus_assert (connection->refcount.value == 0);
1070 /* You have to disconnect the connection before unref:ing it. Otherwise
1071 * you won't get the disconnected message.
1073 _dbus_assert (!_dbus_transport_get_is_connected (connection->transport));
1075 /* ---- We're going to call various application callbacks here, hope it doesn't break anything... */
1076 _dbus_object_registry_free_all_unlocked (connection->objects);
1078 dbus_connection_set_dispatch_status_function (connection, NULL, NULL, NULL);
1079 dbus_connection_set_wakeup_main_function (connection, NULL, NULL, NULL);
1080 dbus_connection_set_unix_user_function (connection, NULL, NULL, NULL);
1082 _dbus_watch_list_free (connection->watches);
1083 connection->watches = NULL;
1085 _dbus_timeout_list_free (connection->timeouts);
1086 connection->timeouts = NULL;
1088 _dbus_data_slot_list_free (&connection->slot_list);
1089 /* ---- Done with stuff that invokes application callbacks */
1091 link = _dbus_list_get_first_link (&connection->filter_list);
1092 while (link != NULL)
1094 DBusMessageHandler *h = link->data;
1095 DBusList *next = _dbus_list_get_next_link (&connection->filter_list, link);
1097 _dbus_message_handler_remove_connection (h, connection);
1102 _dbus_object_registry_unref (connection->objects);
1104 _dbus_hash_table_unref (connection->pending_replies);
1105 connection->pending_replies = NULL;
1107 _dbus_list_clear (&connection->filter_list);
1109 _dbus_list_foreach (&connection->outgoing_messages,
1110 free_outgoing_message,
1112 _dbus_list_clear (&connection->outgoing_messages);
1114 _dbus_list_foreach (&connection->incoming_messages,
1115 (DBusForeachFunction) dbus_message_unref,
1117 _dbus_list_clear (&connection->incoming_messages);
1119 _dbus_counter_unref (connection->outgoing_counter);
1121 _dbus_transport_unref (connection->transport);
1123 if (connection->disconnect_message_link)
1125 DBusMessage *message = connection->disconnect_message_link->data;
1126 dbus_message_unref (message);
1127 _dbus_list_free_link (connection->disconnect_message_link);
1130 _dbus_list_clear (&connection->link_cache);
1132 dbus_condvar_free (connection->dispatch_cond);
1133 dbus_condvar_free (connection->io_path_cond);
1134 dbus_condvar_free (connection->message_returned_cond);
1136 dbus_mutex_free (connection->mutex);
1138 dbus_free (connection);
1142 * Decrements the reference count of a DBusConnection, and finalizes
1143 * it if the count reaches zero. It is a bug to drop the last reference
1144 * to a connection that has not been disconnected.
1146 * @todo in practice it can be quite tricky to never unref a connection
1147 * that's still connected; maybe there's some way we could avoid
1150 * @param connection the connection.
1153 dbus_connection_unref (DBusConnection *connection)
1155 dbus_bool_t last_unref;
1157 _dbus_return_if_fail (connection != NULL);
1159 /* The connection lock is better than the global
1160 * lock in the atomic increment fallback
1163 #ifdef DBUS_HAVE_ATOMIC_INT
1164 last_unref = (_dbus_atomic_dec (&connection->refcount) == 1);
1166 CONNECTION_LOCK (connection);
1168 _dbus_assert (connection->refcount.value > 0);
1170 connection->refcount.value -= 1;
1171 last_unref = (connection->refcount.value == 0);
1174 printf ("unref() connection %p count = %d\n", connection, connection->refcount.value);
1177 CONNECTION_UNLOCK (connection);
1181 _dbus_connection_last_unref (connection);
1185 * Closes the connection, so no further data can be sent or received.
1186 * Any further attempts to send data will result in errors. This
1187 * function does not affect the connection's reference count. It's
1188 * safe to disconnect a connection more than once; all calls after the
1189 * first do nothing. It's impossible to "reconnect" a connection, a
1190 * new connection must be created.
1192 * @param connection the connection.
1195 dbus_connection_disconnect (DBusConnection *connection)
1197 _dbus_return_if_fail (connection != NULL);
1199 CONNECTION_LOCK (connection);
1200 _dbus_transport_disconnect (connection->transport);
1201 CONNECTION_UNLOCK (connection);
1205 _dbus_connection_get_is_connected_unlocked (DBusConnection *connection)
1207 return _dbus_transport_get_is_connected (connection->transport);
1211 * Gets whether the connection is currently connected. All
1212 * connections are connected when they are opened. A connection may
1213 * become disconnected when the remote application closes its end, or
1214 * exits; a connection may also be disconnected with
1215 * dbus_connection_disconnect().
1217 * @param connection the connection.
1218 * @returns #TRUE if the connection is still alive.
1221 dbus_connection_get_is_connected (DBusConnection *connection)
1225 _dbus_return_val_if_fail (connection != NULL, FALSE);
1227 CONNECTION_LOCK (connection);
1228 res = _dbus_connection_get_is_connected_unlocked (connection);
1229 CONNECTION_UNLOCK (connection);
1235 * Gets whether the connection was authenticated. (Note that
1236 * if the connection was authenticated then disconnected,
1237 * this function still returns #TRUE)
1239 * @param connection the connection
1240 * @returns #TRUE if the connection was ever authenticated
1243 dbus_connection_get_is_authenticated (DBusConnection *connection)
1247 _dbus_return_val_if_fail (connection != NULL, FALSE);
1249 CONNECTION_LOCK (connection);
1250 res = _dbus_transport_get_is_authenticated (connection->transport);
1251 CONNECTION_UNLOCK (connection);
1256 struct DBusPreallocatedSend
1258 DBusConnection *connection;
1259 DBusList *queue_link;
1260 DBusList *counter_link;
1263 static DBusPreallocatedSend*
1264 _dbus_connection_preallocate_send_unlocked (DBusConnection *connection)
1266 DBusPreallocatedSend *preallocated;
1268 _dbus_return_val_if_fail (connection != NULL, NULL);
1270 preallocated = dbus_new (DBusPreallocatedSend, 1);
1271 if (preallocated == NULL)
1274 if (connection->link_cache != NULL)
1276 preallocated->queue_link =
1277 _dbus_list_pop_first_link (&connection->link_cache);
1278 preallocated->queue_link->data = NULL;
1282 preallocated->queue_link = _dbus_list_alloc_link (NULL);
1283 if (preallocated->queue_link == NULL)
1287 if (connection->link_cache != NULL)
1289 preallocated->counter_link =
1290 _dbus_list_pop_first_link (&connection->link_cache);
1291 preallocated->counter_link->data = connection->outgoing_counter;
1295 preallocated->counter_link = _dbus_list_alloc_link (connection->outgoing_counter);
1296 if (preallocated->counter_link == NULL)
1300 _dbus_counter_ref (preallocated->counter_link->data);
1302 preallocated->connection = connection;
1304 return preallocated;
1307 _dbus_list_free_link (preallocated->queue_link);
1309 dbus_free (preallocated);
1315 * Preallocates resources needed to send a message, allowing the message
1316 * to be sent without the possibility of memory allocation failure.
1317 * Allows apps to create a future guarantee that they can send
1318 * a message regardless of memory shortages.
1320 * @param connection the connection we're preallocating for.
1321 * @returns the preallocated resources, or #NULL
1323 DBusPreallocatedSend*
1324 dbus_connection_preallocate_send (DBusConnection *connection)
1326 DBusPreallocatedSend *preallocated;
1328 _dbus_return_val_if_fail (connection != NULL, NULL);
1330 CONNECTION_LOCK (connection);
1333 _dbus_connection_preallocate_send_unlocked (connection);
1335 CONNECTION_UNLOCK (connection);
1337 return preallocated;
1341 * Frees preallocated message-sending resources from
1342 * dbus_connection_preallocate_send(). Should only
1343 * be called if the preallocated resources are not used
1344 * to send a message.
1346 * @param connection the connection
1347 * @param preallocated the resources
1350 dbus_connection_free_preallocated_send (DBusConnection *connection,
1351 DBusPreallocatedSend *preallocated)
1353 _dbus_return_if_fail (connection != NULL);
1354 _dbus_return_if_fail (preallocated != NULL);
1355 _dbus_return_if_fail (connection == preallocated->connection);
1357 _dbus_list_free_link (preallocated->queue_link);
1358 _dbus_counter_unref (preallocated->counter_link->data);
1359 _dbus_list_free_link (preallocated->counter_link);
1360 dbus_free (preallocated);
1364 _dbus_connection_send_preallocated_unlocked (DBusConnection *connection,
1365 DBusPreallocatedSend *preallocated,
1366 DBusMessage *message,
1367 dbus_uint32_t *client_serial)
1369 dbus_uint32_t serial;
1371 preallocated->queue_link->data = message;
1372 _dbus_list_prepend_link (&connection->outgoing_messages,
1373 preallocated->queue_link);
1375 _dbus_message_add_size_counter_link (message,
1376 preallocated->counter_link);
1378 dbus_free (preallocated);
1379 preallocated = NULL;
1381 dbus_message_ref (message);
1383 connection->n_outgoing += 1;
1385 _dbus_verbose ("Message %p (%s) added to outgoing queue %p, %d pending to send\n",
1387 dbus_message_get_name (message),
1389 connection->n_outgoing);
1391 if (dbus_message_get_serial (message) == 0)
1393 serial = _dbus_connection_get_next_client_serial (connection);
1394 _dbus_message_set_serial (message, serial);
1396 *client_serial = serial;
1401 *client_serial = dbus_message_get_serial (message);
1404 _dbus_message_lock (message);
1406 if (connection->n_outgoing == 1)
1407 _dbus_transport_messages_pending (connection->transport,
1408 connection->n_outgoing);
1410 _dbus_connection_wakeup_mainloop (connection);
1414 * Sends a message using preallocated resources. This function cannot fail.
1415 * It works identically to dbus_connection_send() in other respects.
1416 * Preallocated resources comes from dbus_connection_preallocate_send().
1417 * This function "consumes" the preallocated resources, they need not
1418 * be freed separately.
1420 * @param connection the connection
1421 * @param preallocated the preallocated resources
1422 * @param message the message to send
1423 * @param client_serial return location for client serial assigned to the message
1426 dbus_connection_send_preallocated (DBusConnection *connection,
1427 DBusPreallocatedSend *preallocated,
1428 DBusMessage *message,
1429 dbus_uint32_t *client_serial)
1431 _dbus_return_if_fail (connection != NULL);
1432 _dbus_return_if_fail (preallocated != NULL);
1433 _dbus_return_if_fail (message != NULL);
1434 _dbus_return_if_fail (preallocated->connection == connection);
1435 _dbus_return_if_fail (dbus_message_get_name (message) != NULL);
1437 CONNECTION_LOCK (connection);
1438 _dbus_connection_send_preallocated_unlocked (connection,
1440 message, client_serial);
1441 CONNECTION_UNLOCK (connection);
1445 * Adds a message to the outgoing message queue. Does not block to
1446 * write the message to the network; that happens asynchronously. To
1447 * force the message to be written, call dbus_connection_flush().
1448 * Because this only queues the message, the only reason it can
1449 * fail is lack of memory. Even if the connection is disconnected,
1450 * no error will be returned.
1452 * If the function fails due to lack of memory, it returns #FALSE.
1453 * The function will never fail for other reasons; even if the
1454 * connection is disconnected, you can queue an outgoing message,
1455 * though obviously it won't be sent.
1457 * @param connection the connection.
1458 * @param message the message to write.
1459 * @param client_serial return location for client serial.
1460 * @returns #TRUE on success.
1463 dbus_connection_send (DBusConnection *connection,
1464 DBusMessage *message,
1465 dbus_uint32_t *client_serial)
1467 DBusPreallocatedSend *preallocated;
1469 _dbus_return_val_if_fail (connection != NULL, FALSE);
1470 _dbus_return_val_if_fail (message != NULL, FALSE);
1472 CONNECTION_LOCK (connection);
1474 preallocated = _dbus_connection_preallocate_send_unlocked (connection);
1475 if (preallocated == NULL)
1477 CONNECTION_UNLOCK (connection);
1482 _dbus_connection_send_preallocated_unlocked (connection,
1486 CONNECTION_UNLOCK (connection);
1492 reply_handler_timeout (void *data)
1494 DBusConnection *connection;
1495 ReplyHandlerData *reply_handler_data = data;
1496 DBusDispatchStatus status;
1498 connection = reply_handler_data->connection;
1500 CONNECTION_LOCK (connection);
1501 if (reply_handler_data->timeout_link)
1503 _dbus_connection_queue_synthesized_message_link (connection,
1504 reply_handler_data->timeout_link);
1505 reply_handler_data->timeout_link = NULL;
1508 _dbus_connection_remove_timeout (connection,
1509 reply_handler_data->timeout);
1510 reply_handler_data->timeout_added = FALSE;
1512 status = _dbus_connection_get_dispatch_status_unlocked (connection);
1514 /* Unlocks, and calls out to user code */
1515 _dbus_connection_update_dispatch_status_and_unlock (connection, status);
1521 reply_handler_data_free (ReplyHandlerData *data)
1526 if (data->timeout_added)
1527 _dbus_connection_remove_timeout_locked (data->connection,
1530 if (data->connection_added)
1531 _dbus_message_handler_remove_connection (data->handler,
1534 if (data->timeout_link)
1536 dbus_message_unref ((DBusMessage *)data->timeout_link->data);
1537 _dbus_list_free_link (data->timeout_link);
1540 dbus_message_handler_unref (data->handler);
1546 * Queues a message to send, as with dbus_connection_send_message(),
1547 * but also sets up a DBusMessageHandler to receive a reply to the
1548 * message. If no reply is received in the given timeout_milliseconds,
1549 * expires the pending reply and sends the DBusMessageHandler a
1550 * synthetic error reply (generated in-process, not by the remote
1551 * application) indicating that a timeout occurred.
1553 * Reply handlers see their replies after message filters see them,
1554 * but before message handlers added with
1555 * dbus_connection_register_handler() see them, regardless of the
1556 * reply message's name. Reply handlers are only handed a single
1557 * message as a reply, after one reply has been seen the handler is
1558 * removed. If a filter filters out the reply before the handler sees
1559 * it, the reply is immediately timed out and a timeout error reply is
1560 * generated. If a filter removes the timeout error reply then the
1561 * reply handler will never be called. Filters should not do this.
1563 * If #NULL is passed for the reply_handler, the timeout reply will
1564 * still be generated and placed into the message queue, but no
1565 * specific message handler will receive the reply.
1567 * If -1 is passed for the timeout, a sane default timeout is used. -1
1568 * is typically the best value for the timeout for this reason, unless
1569 * you want a very short or very long timeout. There is no way to
1570 * avoid a timeout entirely, other than passing INT_MAX for the
1571 * timeout to postpone it indefinitely.
1573 * @param connection the connection
1574 * @param message the message to send
1575 * @param reply_handler message handler expecting the reply, or #NULL
1576 * @param timeout_milliseconds timeout in milliseconds or -1 for default
1577 * @returns #TRUE if the message is successfully queued, #FALSE if no memory.
1581 dbus_connection_send_with_reply (DBusConnection *connection,
1582 DBusMessage *message,
1583 DBusMessageHandler *reply_handler,
1584 int timeout_milliseconds)
1586 DBusTimeout *timeout;
1587 ReplyHandlerData *data;
1589 DBusList *reply_link;
1590 dbus_int32_t serial = -1;
1592 _dbus_return_val_if_fail (connection != NULL, FALSE);
1593 _dbus_return_val_if_fail (message != NULL, FALSE);
1594 _dbus_return_val_if_fail (reply_handler != NULL, FALSE);
1595 _dbus_return_val_if_fail (timeout_milliseconds >= 0 || timeout_milliseconds == -1, FALSE);
1597 if (timeout_milliseconds == -1)
1598 timeout_milliseconds = DEFAULT_TIMEOUT_VALUE;
1600 data = dbus_new0 (ReplyHandlerData, 1);
1605 timeout = _dbus_timeout_new (timeout_milliseconds, reply_handler_timeout,
1610 reply_handler_data_free (data);
1614 CONNECTION_LOCK (connection);
1617 if (!_dbus_connection_add_timeout (connection, timeout))
1619 reply_handler_data_free (data);
1620 _dbus_timeout_unref (timeout);
1621 CONNECTION_UNLOCK (connection);
1625 /* The connection now owns the reference to the timeout. */
1626 _dbus_timeout_unref (timeout);
1628 data->timeout_added = TRUE;
1629 data->timeout = timeout;
1630 data->connection = connection;
1632 if (!_dbus_message_handler_add_connection (reply_handler, connection))
1634 CONNECTION_UNLOCK (connection);
1635 reply_handler_data_free (data);
1638 data->connection_added = TRUE;
1640 /* Assign a serial to the message */
1641 if (dbus_message_get_serial (message) == 0)
1643 serial = _dbus_connection_get_next_client_serial (connection);
1644 _dbus_message_set_serial (message, serial);
1647 data->handler = reply_handler;
1648 data->serial = serial;
1650 dbus_message_handler_ref (reply_handler);
1652 reply = dbus_message_new_error (message, DBUS_ERROR_NO_REPLY,
1653 "No reply within specified time");
1656 CONNECTION_UNLOCK (connection);
1657 reply_handler_data_free (data);
1661 reply_link = _dbus_list_alloc_link (reply);
1664 CONNECTION_UNLOCK (connection);
1665 dbus_message_unref (reply);
1666 reply_handler_data_free (data);
1670 data->timeout_link = reply_link;
1672 /* Insert the serial in the pending replies hash. */
1673 if (!_dbus_hash_table_insert_int (connection->pending_replies, serial, data))
1675 CONNECTION_UNLOCK (connection);
1676 reply_handler_data_free (data);
1680 CONNECTION_UNLOCK (connection);
1682 if (!dbus_connection_send (connection, message, NULL))
1684 /* This will free the handler data too */
1685 _dbus_hash_table_remove_int (connection->pending_replies, serial);
1694 check_for_reply_unlocked (DBusConnection *connection,
1695 dbus_uint32_t client_serial)
1699 link = _dbus_list_get_first_link (&connection->incoming_messages);
1701 while (link != NULL)
1703 DBusMessage *reply = link->data;
1705 if (dbus_message_get_reply_serial (reply) == client_serial)
1707 _dbus_list_remove_link (&connection->incoming_messages, link);
1708 connection->n_incoming -= 1;
1709 dbus_message_ref (reply);
1712 link = _dbus_list_get_next_link (&connection->incoming_messages, link);
1719 * Sends a message and blocks a certain time period while waiting for a reply.
1720 * This function does not dispatch any message handlers until the main loop
1721 * has been reached. This function is used to do non-reentrant "method calls."
1722 * If a reply is received, it is returned, and removed from the incoming
1723 * message queue. If it is not received, #NULL is returned and the
1724 * error is set to #DBUS_ERROR_NO_REPLY. If something else goes
1725 * wrong, result is set to whatever is appropriate, such as
1726 * #DBUS_ERROR_NO_MEMORY or #DBUS_ERROR_DISCONNECTED.
1728 * @todo could use performance improvements (it keeps scanning
1729 * the whole message queue for example) and has thread issues,
1730 * see comments in source
1732 * @param connection the connection
1733 * @param message the message to send
1734 * @param timeout_milliseconds timeout in milliseconds or -1 for default
1735 * @param error return location for error message
1736 * @returns the message that is the reply or #NULL with an error code if the
1740 dbus_connection_send_with_reply_and_block (DBusConnection *connection,
1741 DBusMessage *message,
1742 int timeout_milliseconds,
1745 dbus_uint32_t client_serial;
1746 long start_tv_sec, start_tv_usec;
1747 long end_tv_sec, end_tv_usec;
1748 long tv_sec, tv_usec;
1749 DBusDispatchStatus status;
1751 _dbus_return_val_if_fail (connection != NULL, NULL);
1752 _dbus_return_val_if_fail (message != NULL, NULL);
1753 _dbus_return_val_if_fail (timeout_milliseconds >= 0 || timeout_milliseconds == -1, FALSE);
1754 _dbus_return_val_if_error_is_set (error, NULL);
1756 if (timeout_milliseconds == -1)
1757 timeout_milliseconds = DEFAULT_TIMEOUT_VALUE;
1759 /* it would probably seem logical to pass in _DBUS_INT_MAX
1760 * for infinite timeout, but then math below would get
1761 * all overflow-prone, so smack that down.
1763 if (timeout_milliseconds > _DBUS_ONE_HOUR_IN_MILLISECONDS * 6)
1764 timeout_milliseconds = _DBUS_ONE_HOUR_IN_MILLISECONDS * 6;
1766 if (!dbus_connection_send (connection, message, &client_serial))
1768 _DBUS_SET_OOM (error);
1774 /* Flush message queue */
1775 dbus_connection_flush (connection);
1777 CONNECTION_LOCK (connection);
1779 _dbus_get_current_time (&start_tv_sec, &start_tv_usec);
1780 end_tv_sec = start_tv_sec + timeout_milliseconds / 1000;
1781 end_tv_usec = start_tv_usec + (timeout_milliseconds % 1000) * 1000;
1782 end_tv_sec += end_tv_usec / _DBUS_USEC_PER_SECOND;
1783 end_tv_usec = end_tv_usec % _DBUS_USEC_PER_SECOND;
1785 _dbus_verbose ("dbus_connection_send_with_reply_and_block(): will block %d milliseconds for reply serial %u from %ld sec %ld usec to %ld sec %ld usec\n",
1786 timeout_milliseconds,
1788 start_tv_sec, start_tv_usec,
1789 end_tv_sec, end_tv_usec);
1791 /* Now we wait... */
1792 /* THREAD TODO: This is busted. What if a dispatch() or pop_message
1793 * gets the message before we do?
1795 /* always block at least once as we know we don't have the reply yet */
1796 _dbus_connection_do_iteration (connection,
1797 DBUS_ITERATION_DO_READING |
1798 DBUS_ITERATION_BLOCK,
1799 timeout_milliseconds);
1803 /* queue messages and get status */
1804 status = _dbus_connection_get_dispatch_status_unlocked (connection);
1806 if (status == DBUS_DISPATCH_DATA_REMAINS)
1810 reply = check_for_reply_unlocked (connection, client_serial);
1813 status = _dbus_connection_get_dispatch_status_unlocked (connection);
1815 _dbus_verbose ("dbus_connection_send_with_reply_and_block(): got reply %s\n",
1816 dbus_message_get_name (reply));
1818 /* Unlocks, and calls out to user code */
1819 _dbus_connection_update_dispatch_status_and_unlock (connection, status);
1825 _dbus_get_current_time (&tv_sec, &tv_usec);
1827 if (tv_sec < start_tv_sec)
1828 _dbus_verbose ("dbus_connection_send_with_reply_and_block(): clock set backward\n");
1829 else if (connection->disconnect_message_link == NULL)
1830 _dbus_verbose ("dbus_connection_send_with_reply_and_block(): disconnected\n");
1831 else if (tv_sec < end_tv_sec ||
1832 (tv_sec == end_tv_sec && tv_usec < end_tv_usec))
1834 timeout_milliseconds = (end_tv_sec - tv_sec) * 1000 +
1835 (end_tv_usec - tv_usec) / 1000;
1836 _dbus_verbose ("dbus_connection_send_with_reply_and_block(): %d milliseconds remain\n", timeout_milliseconds);
1837 _dbus_assert (timeout_milliseconds >= 0);
1839 if (status == DBUS_DISPATCH_NEED_MEMORY)
1841 /* Try sleeping a bit, as we aren't sure we need to block for reading,
1842 * we may already have a reply in the buffer and just can't process
1845 _dbus_verbose ("dbus_connection_send_with_reply_and_block() waiting for more memory\n");
1847 if (timeout_milliseconds < 100)
1848 ; /* just busy loop */
1849 else if (timeout_milliseconds <= 1000)
1850 _dbus_sleep_milliseconds (timeout_milliseconds / 3);
1852 _dbus_sleep_milliseconds (1000);
1856 /* block again, we don't have the reply buffered yet. */
1857 _dbus_connection_do_iteration (connection,
1858 DBUS_ITERATION_DO_READING |
1859 DBUS_ITERATION_BLOCK,
1860 timeout_milliseconds);
1863 goto recheck_status;
1866 _dbus_verbose ("dbus_connection_send_with_reply_and_block(): Waited %ld milliseconds and got no reply\n",
1867 (tv_sec - start_tv_sec) * 1000 + (tv_usec - start_tv_usec) / 1000);
1869 if (dbus_connection_get_is_connected (connection))
1870 dbus_set_error (error, DBUS_ERROR_NO_REPLY, "Message did not receive a reply");
1872 dbus_set_error (error, DBUS_ERROR_DISCONNECTED, "Disconnected prior to receiving a reply");
1874 /* unlocks and calls out to user code */
1875 _dbus_connection_update_dispatch_status_and_unlock (connection, status);
1881 * Blocks until the outgoing message queue is empty.
1883 * @param connection the connection.
1886 dbus_connection_flush (DBusConnection *connection)
1888 /* We have to specify DBUS_ITERATION_DO_READING here because
1889 * otherwise we could have two apps deadlock if they are both doing
1890 * a flush(), and the kernel buffers fill up. This could change the
1893 DBusDispatchStatus status;
1895 _dbus_return_if_fail (connection != NULL);
1897 CONNECTION_LOCK (connection);
1898 while (connection->n_outgoing > 0 &&
1899 _dbus_connection_get_is_connected_unlocked (connection))
1900 _dbus_connection_do_iteration (connection,
1901 DBUS_ITERATION_DO_READING |
1902 DBUS_ITERATION_DO_WRITING |
1903 DBUS_ITERATION_BLOCK,
1906 status = _dbus_connection_get_dispatch_status_unlocked (connection);
1908 /* Unlocks and calls out to user code */
1909 _dbus_connection_update_dispatch_status_and_unlock (connection, status);
1912 /* Call with mutex held. Will drop it while waiting and re-acquire
1916 _dbus_connection_wait_for_borrowed (DBusConnection *connection)
1918 _dbus_assert (connection->message_borrowed != NULL);
1920 while (connection->message_borrowed != NULL)
1921 dbus_condvar_wait (connection->message_returned_cond, connection->mutex);
1925 * Returns the first-received message from the incoming message queue,
1926 * leaving it in the queue. If the queue is empty, returns #NULL.
1928 * The caller does not own a reference to the returned message, and
1929 * must either return it using dbus_connection_return_message() or
1930 * keep it after calling dbus_connection_steal_borrowed_message(). No
1931 * one can get at the message while its borrowed, so return it as
1932 * quickly as possible and don't keep a reference to it after
1933 * returning it. If you need to keep the message, make a copy of it.
1935 * @param connection the connection.
1936 * @returns next message in the incoming queue.
1939 dbus_connection_borrow_message (DBusConnection *connection)
1941 DBusMessage *message;
1942 DBusDispatchStatus status;
1944 _dbus_return_val_if_fail (connection != NULL, NULL);
1946 /* this is called for the side effect that it queues
1947 * up any messages from the transport
1949 status = dbus_connection_get_dispatch_status (connection);
1950 if (status != DBUS_DISPATCH_DATA_REMAINS)
1953 CONNECTION_LOCK (connection);
1955 if (connection->message_borrowed != NULL)
1956 _dbus_connection_wait_for_borrowed (connection);
1958 message = _dbus_list_get_first (&connection->incoming_messages);
1961 connection->message_borrowed = message;
1963 CONNECTION_UNLOCK (connection);
1968 * Used to return a message after peeking at it using
1969 * dbus_connection_borrow_message().
1971 * @param connection the connection
1972 * @param message the message from dbus_connection_borrow_message()
1975 dbus_connection_return_message (DBusConnection *connection,
1976 DBusMessage *message)
1978 _dbus_return_if_fail (connection != NULL);
1979 _dbus_return_if_fail (message != NULL);
1981 CONNECTION_LOCK (connection);
1983 _dbus_assert (message == connection->message_borrowed);
1985 connection->message_borrowed = NULL;
1986 dbus_condvar_wake_all (connection->message_returned_cond);
1988 CONNECTION_UNLOCK (connection);
1992 * Used to keep a message after peeking at it using
1993 * dbus_connection_borrow_message(). Before using this function, see
1994 * the caveats/warnings in the documentation for
1995 * dbus_connection_pop_message().
1997 * @param connection the connection
1998 * @param message the message from dbus_connection_borrow_message()
2001 dbus_connection_steal_borrowed_message (DBusConnection *connection,
2002 DBusMessage *message)
2004 DBusMessage *pop_message;
2006 _dbus_return_if_fail (connection != NULL);
2007 _dbus_return_if_fail (message != NULL);
2009 CONNECTION_LOCK (connection);
2011 _dbus_assert (message == connection->message_borrowed);
2013 pop_message = _dbus_list_pop_first (&connection->incoming_messages);
2014 _dbus_assert (message == pop_message);
2016 connection->n_incoming -= 1;
2018 _dbus_verbose ("Incoming message %p stolen from queue, %d incoming\n",
2019 message, connection->n_incoming);
2021 connection->message_borrowed = NULL;
2022 dbus_condvar_wake_all (connection->message_returned_cond);
2024 CONNECTION_UNLOCK (connection);
2027 /* See dbus_connection_pop_message, but requires the caller to own
2028 * the lock before calling. May drop the lock while running.
2031 _dbus_connection_pop_message_link_unlocked (DBusConnection *connection)
2033 if (connection->message_borrowed != NULL)
2034 _dbus_connection_wait_for_borrowed (connection);
2036 if (connection->n_incoming > 0)
2040 link = _dbus_list_pop_first_link (&connection->incoming_messages);
2041 connection->n_incoming -= 1;
2043 _dbus_verbose ("Message %p (%s) removed from incoming queue %p, %d incoming\n",
2044 link->data, dbus_message_get_name (link->data),
2045 connection, connection->n_incoming);
2053 /* See dbus_connection_pop_message, but requires the caller to own
2054 * the lock before calling. May drop the lock while running.
2057 _dbus_connection_pop_message_unlocked (DBusConnection *connection)
2061 link = _dbus_connection_pop_message_link_unlocked (connection);
2065 DBusMessage *message;
2067 message = link->data;
2069 _dbus_list_free_link (link);
2079 * Returns the first-received message from the incoming message queue,
2080 * removing it from the queue. The caller owns a reference to the
2081 * returned message. If the queue is empty, returns #NULL.
2083 * This function bypasses any message handlers that are registered,
2084 * and so using it is usually wrong. Instead, let the main loop invoke
2085 * dbus_connection_dispatch(). Popping messages manually is only
2086 * useful in very simple programs that don't share a #DBusConnection
2087 * with any libraries or other modules.
2089 * @param connection the connection.
2090 * @returns next message in the incoming queue.
2093 dbus_connection_pop_message (DBusConnection *connection)
2095 DBusMessage *message;
2096 DBusDispatchStatus status;
2098 /* this is called for the side effect that it queues
2099 * up any messages from the transport
2101 status = dbus_connection_get_dispatch_status (connection);
2102 if (status != DBUS_DISPATCH_DATA_REMAINS)
2105 CONNECTION_LOCK (connection);
2107 message = _dbus_connection_pop_message_unlocked (connection);
2109 _dbus_verbose ("Returning popped message %p\n", message);
2111 CONNECTION_UNLOCK (connection);
2117 * Acquire the dispatcher. This must be done before dispatching
2118 * messages in order to guarantee the right order of
2119 * message delivery. May sleep and drop the connection mutex
2120 * while waiting for the dispatcher.
2122 * @param connection the connection.
2125 _dbus_connection_acquire_dispatch (DBusConnection *connection)
2127 if (connection->dispatch_acquired)
2128 dbus_condvar_wait (connection->dispatch_cond, connection->mutex);
2129 _dbus_assert (!connection->dispatch_acquired);
2131 connection->dispatch_acquired = TRUE;
2135 * Release the dispatcher when you're done with it. Only call
2136 * after you've acquired the dispatcher. Wakes up at most one
2137 * thread currently waiting to acquire the dispatcher.
2139 * @param connection the connection.
2142 _dbus_connection_release_dispatch (DBusConnection *connection)
2144 _dbus_assert (connection->dispatch_acquired);
2146 connection->dispatch_acquired = FALSE;
2147 dbus_condvar_wake_one (connection->dispatch_cond);
2151 _dbus_connection_failed_pop (DBusConnection *connection,
2152 DBusList *message_link)
2154 _dbus_list_prepend_link (&connection->incoming_messages,
2156 connection->n_incoming += 1;
2159 static DBusDispatchStatus
2160 _dbus_connection_get_dispatch_status_unlocked (DBusConnection *connection)
2162 if (connection->n_incoming > 0)
2163 return DBUS_DISPATCH_DATA_REMAINS;
2164 else if (!_dbus_transport_queue_messages (connection->transport))
2165 return DBUS_DISPATCH_NEED_MEMORY;
2168 DBusDispatchStatus status;
2170 status = _dbus_transport_get_dispatch_status (connection->transport);
2172 if (status != DBUS_DISPATCH_COMPLETE)
2174 else if (connection->n_incoming > 0)
2175 return DBUS_DISPATCH_DATA_REMAINS;
2177 return DBUS_DISPATCH_COMPLETE;
2182 _dbus_connection_update_dispatch_status_and_unlock (DBusConnection *connection,
2183 DBusDispatchStatus new_status)
2185 dbus_bool_t changed;
2186 DBusDispatchStatusFunction function;
2189 /* We have the lock */
2191 _dbus_connection_ref_unlocked (connection);
2193 changed = new_status != connection->last_dispatch_status;
2195 connection->last_dispatch_status = new_status;
2197 function = connection->dispatch_status_function;
2198 data = connection->dispatch_status_data;
2200 /* We drop the lock */
2201 CONNECTION_UNLOCK (connection);
2203 if (changed && function)
2205 _dbus_verbose ("Notifying of change to dispatch status of %p now %d (%s)\n",
2206 connection, new_status,
2207 new_status == DBUS_DISPATCH_COMPLETE ? "complete" :
2208 new_status == DBUS_DISPATCH_DATA_REMAINS ? "data remains" :
2209 new_status == DBUS_DISPATCH_NEED_MEMORY ? "need memory" :
2211 (* function) (connection, new_status, data);
2214 dbus_connection_unref (connection);
2218 * Gets the current state (what we would currently return
2219 * from dbus_connection_dispatch()) but doesn't actually
2220 * dispatch any messages.
2222 * @param connection the connection.
2223 * @returns current dispatch status
2226 dbus_connection_get_dispatch_status (DBusConnection *connection)
2228 DBusDispatchStatus status;
2230 _dbus_return_val_if_fail (connection != NULL, DBUS_DISPATCH_COMPLETE);
2232 CONNECTION_LOCK (connection);
2234 status = _dbus_connection_get_dispatch_status_unlocked (connection);
2236 CONNECTION_UNLOCK (connection);
2242 * Processes data buffered while handling watches, queueing zero or
2243 * more incoming messages. Then pops the first-received message from
2244 * the current incoming message queue, runs any handlers for it, and
2245 * unrefs the message. Returns a status indicating whether messages/data
2246 * remain, more memory is needed, or all data has been processed.
2248 * Even if the dispatch status is #DBUS_DISPATCH_DATA_REMAINS,
2249 * does not necessarily dispatch a message, as the data may
2250 * be part of authentication or the like.
2252 * @todo some FIXME in here about handling DBUS_HANDLER_RESULT_NEED_MEMORY
2254 * @param connection the connection
2255 * @returns dispatch status
2258 dbus_connection_dispatch (DBusConnection *connection)
2260 DBusMessage *message;
2261 DBusList *link, *filter_list_copy, *message_link;
2262 DBusHandlerResult result;
2263 ReplyHandlerData *reply_handler_data;
2264 dbus_int32_t reply_serial;
2265 DBusDispatchStatus status;
2267 _dbus_return_val_if_fail (connection != NULL, DBUS_DISPATCH_COMPLETE);
2269 CONNECTION_LOCK (connection);
2270 status = _dbus_connection_get_dispatch_status_unlocked (connection);
2271 if (status != DBUS_DISPATCH_DATA_REMAINS)
2273 /* unlocks and calls out to user code */
2274 _dbus_connection_update_dispatch_status_and_unlock (connection, status);
2278 /* We need to ref the connection since the callback could potentially
2279 * drop the last ref to it
2281 _dbus_connection_ref_unlocked (connection);
2283 _dbus_connection_acquire_dispatch (connection);
2285 /* This call may drop the lock during the execution (if waiting for
2286 * borrowed messages to be returned) but the order of message
2287 * dispatch if several threads call dispatch() is still
2288 * protected by the lock, since only one will get the lock, and that
2289 * one will finish the message dispatching
2291 message_link = _dbus_connection_pop_message_link_unlocked (connection);
2292 if (message_link == NULL)
2294 /* another thread dispatched our stuff */
2296 _dbus_connection_release_dispatch (connection);
2298 status = _dbus_connection_get_dispatch_status_unlocked (connection);
2300 _dbus_connection_update_dispatch_status_and_unlock (connection, status);
2302 dbus_connection_unref (connection);
2307 message = message_link->data;
2309 result = DBUS_HANDLER_RESULT_ALLOW_MORE_HANDLERS;
2311 reply_serial = dbus_message_get_reply_serial (message);
2312 reply_handler_data = _dbus_hash_table_lookup_int (connection->pending_replies,
2315 if (!_dbus_list_copy (&connection->filter_list, &filter_list_copy))
2317 _dbus_connection_release_dispatch (connection);
2319 _dbus_connection_failed_pop (connection, message_link);
2321 /* unlocks and calls user code */
2322 _dbus_connection_update_dispatch_status_and_unlock (connection,
2323 DBUS_DISPATCH_NEED_MEMORY);
2325 dbus_connection_unref (connection);
2327 return DBUS_DISPATCH_NEED_MEMORY;
2330 _dbus_list_foreach (&filter_list_copy,
2331 (DBusForeachFunction)dbus_message_handler_ref,
2334 /* We're still protected from dispatch() reentrancy here
2335 * since we acquired the dispatcher
2337 CONNECTION_UNLOCK (connection);
2339 link = _dbus_list_get_first_link (&filter_list_copy);
2340 while (link != NULL)
2342 DBusMessageHandler *handler = link->data;
2343 DBusList *next = _dbus_list_get_next_link (&filter_list_copy, link);
2345 _dbus_verbose (" running filter on message %p\n", message);
2346 result = _dbus_message_handler_handle_message (handler, connection,
2349 if (result != DBUS_HANDLER_RESULT_ALLOW_MORE_HANDLERS)
2355 _dbus_list_foreach (&filter_list_copy,
2356 (DBusForeachFunction)dbus_message_handler_unref,
2358 _dbus_list_clear (&filter_list_copy);
2360 CONNECTION_LOCK (connection);
2362 if (result == DBUS_HANDLER_RESULT_NEED_MEMORY)
2365 /* Did a reply we were waiting on get filtered? */
2366 if (reply_handler_data && result == DBUS_HANDLER_RESULT_REMOVE_MESSAGE)
2368 /* Queue the timeout immediately! */
2369 if (reply_handler_data->timeout_link)
2371 _dbus_connection_queue_synthesized_message_link (connection,
2372 reply_handler_data->timeout_link);
2373 reply_handler_data->timeout_link = NULL;
2377 /* We already queued the timeout? Then it was filtered! */
2378 _dbus_warn ("The timeout error with reply serial %d was filtered, so the reply handler will never be called.\n", reply_serial);
2382 if (result == DBUS_HANDLER_RESULT_REMOVE_MESSAGE)
2385 if (reply_handler_data)
2387 CONNECTION_UNLOCK (connection);
2389 _dbus_verbose (" running reply handler on message %p\n", message);
2391 result = _dbus_message_handler_handle_message (reply_handler_data->handler,
2392 connection, message);
2393 reply_handler_data_free (reply_handler_data);
2394 CONNECTION_LOCK (connection);
2398 /* We're still protected from dispatch() reentrancy here
2399 * since we acquired the dispatcher
2401 _dbus_verbose (" running object handler on message %p (%s)\n",
2402 message, dbus_message_get_name (message));
2404 result = _dbus_object_registry_handle_and_unlock (connection->objects,
2407 CONNECTION_LOCK (connection);
2408 if (result == DBUS_HANDLER_RESULT_REMOVE_MESSAGE)
2411 if (result == DBUS_HANDLER_RESULT_NEED_MEMORY)
2414 _dbus_verbose (" done dispatching %p (%s) on connection %p\n", message,
2415 dbus_message_get_name (message), connection);
2418 _dbus_connection_release_dispatch (connection);
2420 _dbus_list_free_link (message_link);
2421 dbus_message_unref (message); /* don't want the message to count in max message limits
2422 * in computing dispatch status
2425 status = _dbus_connection_get_dispatch_status_unlocked (connection);
2427 /* unlocks and calls user code */
2428 _dbus_connection_update_dispatch_status_and_unlock (connection, status);
2430 dbus_connection_unref (connection);
2436 * Sets the watch functions for the connection. These functions are
2437 * responsible for making the application's main loop aware of file
2438 * descriptors that need to be monitored for events, using select() or
2439 * poll(). When using Qt, typically the DBusAddWatchFunction would
2440 * create a QSocketNotifier. When using GLib, the DBusAddWatchFunction
2441 * could call g_io_add_watch(), or could be used as part of a more
2442 * elaborate GSource. Note that when a watch is added, it may
2445 * The DBusWatchToggledFunction notifies the application that the
2446 * watch has been enabled or disabled. Call dbus_watch_get_enabled()
2447 * to check this. A disabled watch should have no effect, and enabled
2448 * watch should be added to the main loop. This feature is used
2449 * instead of simply adding/removing the watch because
2450 * enabling/disabling can be done without memory allocation. The
2451 * toggled function may be NULL if a main loop re-queries
2452 * dbus_watch_get_enabled() every time anyway.
2454 * The DBusWatch can be queried for the file descriptor to watch using
2455 * dbus_watch_get_fd(), and for the events to watch for using
2456 * dbus_watch_get_flags(). The flags returned by
2457 * dbus_watch_get_flags() will only contain DBUS_WATCH_READABLE and
2458 * DBUS_WATCH_WRITABLE, never DBUS_WATCH_HANGUP or DBUS_WATCH_ERROR;
2459 * all watches implicitly include a watch for hangups, errors, and
2460 * other exceptional conditions.
2462 * Once a file descriptor becomes readable or writable, or an exception
2463 * occurs, dbus_watch_handle() should be called to
2464 * notify the connection of the file descriptor's condition.
2466 * dbus_watch_handle() cannot be called during the
2467 * DBusAddWatchFunction, as the connection will not be ready to handle
2470 * It is not allowed to reference a DBusWatch after it has been passed
2471 * to remove_function.
2473 * If #FALSE is returned due to lack of memory, the failure may be due
2474 * to a #FALSE return from the new add_function. If so, the
2475 * add_function may have been called successfully one or more times,
2476 * but the remove_function will also have been called to remove any
2477 * successful adds. i.e. if #FALSE is returned the net result
2478 * should be that dbus_connection_set_watch_functions() has no effect,
2479 * but the add_function and remove_function may have been called.
2481 * @todo We need to drop the lock when we call the
2482 * add/remove/toggled functions which can be a side effect
2483 * of setting the watch functions.
2485 * @param connection the connection.
2486 * @param add_function function to begin monitoring a new descriptor.
2487 * @param remove_function function to stop monitoring a descriptor.
2488 * @param toggled_function function to notify of enable/disable
2489 * @param data data to pass to add_function and remove_function.
2490 * @param free_data_function function to be called to free the data.
2491 * @returns #FALSE on failure (no memory)
2494 dbus_connection_set_watch_functions (DBusConnection *connection,
2495 DBusAddWatchFunction add_function,
2496 DBusRemoveWatchFunction remove_function,
2497 DBusWatchToggledFunction toggled_function,
2499 DBusFreeFunction free_data_function)
2503 _dbus_return_val_if_fail (connection != NULL, FALSE);
2505 CONNECTION_LOCK (connection);
2506 /* ref connection for slightly better reentrancy */
2507 _dbus_connection_ref_unlocked (connection);
2509 /* FIXME this can call back into user code, and we need to drop the
2510 * connection lock when it does.
2512 retval = _dbus_watch_list_set_functions (connection->watches,
2513 add_function, remove_function,
2515 data, free_data_function);
2517 CONNECTION_UNLOCK (connection);
2518 /* drop our paranoid refcount */
2519 dbus_connection_unref (connection);
2525 * Sets the timeout functions for the connection. These functions are
2526 * responsible for making the application's main loop aware of timeouts.
2527 * When using Qt, typically the DBusAddTimeoutFunction would create a
2528 * QTimer. When using GLib, the DBusAddTimeoutFunction would call
2531 * The DBusTimeoutToggledFunction notifies the application that the
2532 * timeout has been enabled or disabled. Call
2533 * dbus_timeout_get_enabled() to check this. A disabled timeout should
2534 * have no effect, and enabled timeout should be added to the main
2535 * loop. This feature is used instead of simply adding/removing the
2536 * timeout because enabling/disabling can be done without memory
2537 * allocation. With Qt, QTimer::start() and QTimer::stop() can be used
2538 * to enable and disable. The toggled function may be NULL if a main
2539 * loop re-queries dbus_timeout_get_enabled() every time anyway.
2540 * Whenever a timeout is toggled, its interval may change.
2542 * The DBusTimeout can be queried for the timer interval using
2543 * dbus_timeout_get_interval(). dbus_timeout_handle() should be called
2544 * repeatedly, each time the interval elapses, starting after it has
2545 * elapsed once. The timeout stops firing when it is removed with the
2546 * given remove_function. The timer interval may change whenever the
2547 * timeout is added, removed, or toggled.
2549 * @param connection the connection.
2550 * @param add_function function to add a timeout.
2551 * @param remove_function function to remove a timeout.
2552 * @param toggled_function function to notify of enable/disable
2553 * @param data data to pass to add_function and remove_function.
2554 * @param free_data_function function to be called to free the data.
2555 * @returns #FALSE on failure (no memory)
2558 dbus_connection_set_timeout_functions (DBusConnection *connection,
2559 DBusAddTimeoutFunction add_function,
2560 DBusRemoveTimeoutFunction remove_function,
2561 DBusTimeoutToggledFunction toggled_function,
2563 DBusFreeFunction free_data_function)
2567 _dbus_return_val_if_fail (connection != NULL, FALSE);
2569 CONNECTION_LOCK (connection);
2570 /* ref connection for slightly better reentrancy */
2571 _dbus_connection_ref_unlocked (connection);
2573 retval = _dbus_timeout_list_set_functions (connection->timeouts,
2574 add_function, remove_function,
2576 data, free_data_function);
2578 CONNECTION_UNLOCK (connection);
2579 /* drop our paranoid refcount */
2580 dbus_connection_unref (connection);
2586 * Sets the mainloop wakeup function for the connection. Thi function is
2587 * responsible for waking up the main loop (if its sleeping) when some some
2588 * change has happened to the connection that the mainloop needs to reconsiders
2589 * (e.g. a message has been queued for writing).
2590 * When using Qt, this typically results in a call to QEventLoop::wakeUp().
2591 * When using GLib, it would call g_main_context_wakeup().
2594 * @param connection the connection.
2595 * @param wakeup_main_function function to wake up the mainloop
2596 * @param data data to pass wakeup_main_function
2597 * @param free_data_function function to be called to free the data.
2600 dbus_connection_set_wakeup_main_function (DBusConnection *connection,
2601 DBusWakeupMainFunction wakeup_main_function,
2603 DBusFreeFunction free_data_function)
2606 DBusFreeFunction old_free_data;
2608 _dbus_return_if_fail (connection != NULL);
2610 CONNECTION_LOCK (connection);
2611 old_data = connection->wakeup_main_data;
2612 old_free_data = connection->free_wakeup_main_data;
2614 connection->wakeup_main_function = wakeup_main_function;
2615 connection->wakeup_main_data = data;
2616 connection->free_wakeup_main_data = free_data_function;
2618 CONNECTION_UNLOCK (connection);
2620 /* Callback outside the lock */
2622 (*old_free_data) (old_data);
2626 * Set a function to be invoked when the dispatch status changes.
2627 * If the dispatch status is #DBUS_DISPATCH_DATA_REMAINS, then
2628 * dbus_connection_dispatch() needs to be called to process incoming
2629 * messages. However, dbus_connection_dispatch() MUST NOT BE CALLED
2630 * from inside the DBusDispatchStatusFunction. Indeed, almost
2631 * any reentrancy in this function is a bad idea. Instead,
2632 * the DBusDispatchStatusFunction should simply save an indication
2633 * that messages should be dispatched later, when the main loop
2636 * @param connection the connection
2637 * @param function function to call on dispatch status changes
2638 * @param data data for function
2639 * @param free_data_function free the function data
2642 dbus_connection_set_dispatch_status_function (DBusConnection *connection,
2643 DBusDispatchStatusFunction function,
2645 DBusFreeFunction free_data_function)
2648 DBusFreeFunction old_free_data;
2650 _dbus_return_if_fail (connection != NULL);
2652 CONNECTION_LOCK (connection);
2653 old_data = connection->dispatch_status_data;
2654 old_free_data = connection->free_dispatch_status_data;
2656 connection->dispatch_status_function = function;
2657 connection->dispatch_status_data = data;
2658 connection->free_dispatch_status_data = free_data_function;
2660 CONNECTION_UNLOCK (connection);
2662 /* Callback outside the lock */
2664 (*old_free_data) (old_data);
2668 * Gets the UNIX user ID of the connection if any.
2669 * Returns #TRUE if the uid is filled in.
2670 * Always returns #FALSE on non-UNIX platforms.
2671 * Always returns #FALSE prior to authenticating the
2674 * @param connection the connection
2675 * @param uid return location for the user ID
2676 * @returns #TRUE if uid is filled in with a valid user ID
2679 dbus_connection_get_unix_user (DBusConnection *connection,
2684 _dbus_return_val_if_fail (connection != NULL, FALSE);
2685 _dbus_return_val_if_fail (uid != NULL, FALSE);
2687 CONNECTION_LOCK (connection);
2689 if (!_dbus_transport_get_is_authenticated (connection->transport))
2692 result = _dbus_transport_get_unix_user (connection->transport,
2694 CONNECTION_UNLOCK (connection);
2700 * Sets a predicate function used to determine whether a given user ID
2701 * is allowed to connect. When an incoming connection has
2702 * authenticated with a particular user ID, this function is called;
2703 * if it returns #TRUE, the connection is allowed to proceed,
2704 * otherwise the connection is disconnected.
2706 * If the function is set to #NULL (as it is by default), then
2707 * only the same UID as the server process will be allowed to
2710 * @param connection the connection
2711 * @param function the predicate
2712 * @param data data to pass to the predicate
2713 * @param free_data_function function to free the data
2716 dbus_connection_set_unix_user_function (DBusConnection *connection,
2717 DBusAllowUnixUserFunction function,
2719 DBusFreeFunction free_data_function)
2721 void *old_data = NULL;
2722 DBusFreeFunction old_free_function = NULL;
2724 _dbus_return_if_fail (connection != NULL);
2726 CONNECTION_LOCK (connection);
2727 _dbus_transport_set_unix_user_function (connection->transport,
2728 function, data, free_data_function,
2729 &old_data, &old_free_function);
2730 CONNECTION_UNLOCK (connection);
2732 if (old_free_function != NULL)
2733 (* old_free_function) (old_data);
2737 * Adds a message filter. Filters are handlers that are run on
2738 * all incoming messages, prior to the objects
2739 * registered with dbus_connection_register_object().
2740 * Filters are run in the order that they were added.
2741 * The same handler can be added as a filter more than once, in
2742 * which case it will be run more than once.
2743 * Filters added during a filter callback won't be run on the
2744 * message being processed.
2746 * The connection does NOT add a reference to the message handler;
2747 * instead, if the message handler is finalized, the connection simply
2748 * forgets about it. Thus the caller of this function must keep a
2749 * reference to the message handler.
2751 * @param connection the connection
2752 * @param handler the handler
2753 * @returns #TRUE on success, #FALSE if not enough memory.
2756 dbus_connection_add_filter (DBusConnection *connection,
2757 DBusMessageHandler *handler)
2759 _dbus_return_val_if_fail (connection != NULL, FALSE);
2760 _dbus_return_val_if_fail (handler != NULL, FALSE);
2762 CONNECTION_LOCK (connection);
2763 if (!_dbus_message_handler_add_connection (handler, connection))
2765 CONNECTION_UNLOCK (connection);
2769 if (!_dbus_list_append (&connection->filter_list,
2772 _dbus_message_handler_remove_connection (handler, connection);
2773 CONNECTION_UNLOCK (connection);
2777 CONNECTION_UNLOCK (connection);
2782 * Removes a previously-added message filter. It is a programming
2783 * error to call this function for a handler that has not
2784 * been added as a filter. If the given handler was added
2785 * more than once, only one instance of it will be removed
2786 * (the most recently-added instance).
2788 * @param connection the connection
2789 * @param handler the handler to remove
2793 dbus_connection_remove_filter (DBusConnection *connection,
2794 DBusMessageHandler *handler)
2796 _dbus_return_if_fail (connection != NULL);
2797 _dbus_return_if_fail (handler != NULL);
2799 CONNECTION_LOCK (connection);
2800 if (!_dbus_list_remove_last (&connection->filter_list, handler))
2802 _dbus_warn ("Tried to remove a DBusConnection filter that had not been added\n");
2803 CONNECTION_UNLOCK (connection);
2807 _dbus_message_handler_remove_connection (handler, connection);
2809 CONNECTION_UNLOCK (connection);
2813 * Registers an object with the connection. This object is assigned an
2814 * object ID, and will be visible under this ID and with the provided
2815 * interfaces to the peer application on the other end of the
2816 * connection. The object instance should be passed in as object_impl;
2817 * the instance can be any datatype, as long as it fits in a void*.
2819 * As a side effect of calling this function, the "registered"
2820 * callback in the #DBusObjectVTable will be invoked.
2822 * If the object is deleted, be sure to unregister it with
2823 * dbus_connection_unregister_object() or it will continue to get
2826 * @param connection the connection to register the instance with
2827 * @param interfaces #NULL-terminated array of interface names the instance supports
2828 * @param vtable virtual table of functions for manipulating the instance
2829 * @param object_impl object instance
2830 * @param object_id if non-#NULL, object ID to initialize with the new object's ID
2831 * @returns #FALSE if not enough memory to register the object instance
2834 dbus_connection_register_object (DBusConnection *connection,
2835 const char **interfaces,
2836 const DBusObjectVTable *vtable,
2838 DBusObjectID *object_id)
2840 _dbus_return_val_if_fail (connection != NULL, FALSE);
2841 _dbus_return_val_if_fail (vtable != NULL, FALSE);
2842 _dbus_return_val_if_fail (vtable->dbus_internal_pad1 == NULL, FALSE);
2843 _dbus_return_val_if_fail (vtable->dbus_internal_pad2 == NULL, FALSE);
2844 _dbus_return_val_if_fail (vtable->dbus_internal_pad3 == NULL, FALSE);
2846 CONNECTION_LOCK (connection);
2848 return _dbus_object_registry_add_and_unlock (connection->objects,
2856 * Reverses the effects of dbus_connection_register_object(),
2857 * and invokes the "unregistered" callback in the #DBusObjectVTable
2858 * for the given object. The passed-in object ID must be a valid,
2859 * registered object ID or the results are undefined.
2861 * @param connection the connection to unregister the object ID from
2862 * @param object_id the object ID to unregister
2865 dbus_connection_unregister_object (DBusConnection *connection,
2866 const DBusObjectID *object_id)
2868 _dbus_return_if_fail (connection != NULL);
2870 CONNECTION_LOCK (connection);
2872 return _dbus_object_registry_remove_and_unlock (connection->objects,
2876 static DBusDataSlotAllocator slot_allocator;
2877 _DBUS_DEFINE_GLOBAL_LOCK (connection_slots);
2880 * Allocates an integer ID to be used for storing application-specific
2881 * data on any DBusConnection. The allocated ID may then be used
2882 * with dbus_connection_set_data() and dbus_connection_get_data().
2883 * The passed-in slot must be initialized to -1, and is filled in
2884 * with the slot ID. If the passed-in slot is not -1, it's assumed
2885 * to be already allocated, and its refcount is incremented.
2887 * The allocated slot is global, i.e. all DBusConnection objects will
2888 * have a slot with the given integer ID reserved.
2890 * @param slot_p address of a global variable storing the slot
2891 * @returns #FALSE on failure (no memory)
2894 dbus_connection_allocate_data_slot (dbus_int32_t *slot_p)
2896 return _dbus_data_slot_allocator_alloc (&slot_allocator,
2897 _DBUS_LOCK_NAME (connection_slots),
2902 * Deallocates a global ID for connection data slots.
2903 * dbus_connection_get_data() and dbus_connection_set_data() may no
2904 * longer be used with this slot. Existing data stored on existing
2905 * DBusConnection objects will be freed when the connection is
2906 * finalized, but may not be retrieved (and may only be replaced if
2907 * someone else reallocates the slot). When the refcount on the
2908 * passed-in slot reaches 0, it is set to -1.
2910 * @param slot_p address storing the slot to deallocate
2913 dbus_connection_free_data_slot (dbus_int32_t *slot_p)
2915 _dbus_return_if_fail (*slot_p >= 0);
2917 _dbus_data_slot_allocator_free (&slot_allocator, slot_p);
2921 * Stores a pointer on a DBusConnection, along
2922 * with an optional function to be used for freeing
2923 * the data when the data is set again, or when
2924 * the connection is finalized. The slot number
2925 * must have been allocated with dbus_connection_allocate_data_slot().
2927 * @param connection the connection
2928 * @param slot the slot number
2929 * @param data the data to store
2930 * @param free_data_func finalizer function for the data
2931 * @returns #TRUE if there was enough memory to store the data
2934 dbus_connection_set_data (DBusConnection *connection,
2937 DBusFreeFunction free_data_func)
2939 DBusFreeFunction old_free_func;
2943 _dbus_return_val_if_fail (connection != NULL, FALSE);
2944 _dbus_return_val_if_fail (slot >= 0, FALSE);
2946 CONNECTION_LOCK (connection);
2948 retval = _dbus_data_slot_list_set (&slot_allocator,
2949 &connection->slot_list,
2950 slot, data, free_data_func,
2951 &old_free_func, &old_data);
2953 CONNECTION_UNLOCK (connection);
2957 /* Do the actual free outside the connection lock */
2959 (* old_free_func) (old_data);
2966 * Retrieves data previously set with dbus_connection_set_data().
2967 * The slot must still be allocated (must not have been freed).
2969 * @param connection the connection
2970 * @param slot the slot to get data from
2971 * @returns the data, or #NULL if not found
2974 dbus_connection_get_data (DBusConnection *connection,
2979 _dbus_return_val_if_fail (connection != NULL, NULL);
2981 CONNECTION_LOCK (connection);
2983 res = _dbus_data_slot_list_get (&slot_allocator,
2984 &connection->slot_list,
2987 CONNECTION_UNLOCK (connection);
2993 * This function sets a global flag for whether dbus_connection_new()
2994 * will set SIGPIPE behavior to SIG_IGN.
2996 * @param will_modify_sigpipe #TRUE to allow sigpipe to be set to SIG_IGN
2999 dbus_connection_set_change_sigpipe (dbus_bool_t will_modify_sigpipe)
3001 _dbus_modify_sigpipe = will_modify_sigpipe != FALSE;
3005 * Specifies the maximum size message this connection is allowed to
3006 * receive. Larger messages will result in disconnecting the
3009 * @param connection a #DBusConnection
3010 * @param size maximum message size the connection can receive, in bytes
3013 dbus_connection_set_max_message_size (DBusConnection *connection,
3016 _dbus_return_if_fail (connection != NULL);
3018 CONNECTION_LOCK (connection);
3019 _dbus_transport_set_max_message_size (connection->transport,
3021 CONNECTION_UNLOCK (connection);
3025 * Gets the value set by dbus_connection_set_max_message_size().
3027 * @param connection the connection
3028 * @returns the max size of a single message
3031 dbus_connection_get_max_message_size (DBusConnection *connection)
3035 _dbus_return_val_if_fail (connection != NULL, 0);
3037 CONNECTION_LOCK (connection);
3038 res = _dbus_transport_get_max_message_size (connection->transport);
3039 CONNECTION_UNLOCK (connection);
3044 * Sets the maximum total number of bytes that can be used for all messages
3045 * received on this connection. Messages count toward the maximum until
3046 * they are finalized. When the maximum is reached, the connection will
3047 * not read more data until some messages are finalized.
3049 * The semantics of the maximum are: if outstanding messages are
3050 * already above the maximum, additional messages will not be read.
3051 * The semantics are not: if the next message would cause us to exceed
3052 * the maximum, we don't read it. The reason is that we don't know the
3053 * size of a message until after we read it.
3055 * Thus, the max live messages size can actually be exceeded
3056 * by up to the maximum size of a single message.
3058 * Also, if we read say 1024 bytes off the wire in a single read(),
3059 * and that contains a half-dozen small messages, we may exceed the
3060 * size max by that amount. But this should be inconsequential.
3062 * This does imply that we can't call read() with a buffer larger
3063 * than we're willing to exceed this limit by.
3065 * @param connection the connection
3066 * @param size the maximum size in bytes of all outstanding messages
3069 dbus_connection_set_max_received_size (DBusConnection *connection,
3072 _dbus_return_if_fail (connection != NULL);
3074 CONNECTION_LOCK (connection);
3075 _dbus_transport_set_max_received_size (connection->transport,
3077 CONNECTION_UNLOCK (connection);
3081 * Gets the value set by dbus_connection_set_max_received_size().
3083 * @param connection the connection
3084 * @returns the max size of all live messages
3087 dbus_connection_get_max_received_size (DBusConnection *connection)
3091 _dbus_return_val_if_fail (connection != NULL, 0);
3093 CONNECTION_LOCK (connection);
3094 res = _dbus_transport_get_max_received_size (connection->transport);
3095 CONNECTION_UNLOCK (connection);
3100 * Gets the approximate size in bytes of all messages in the outgoing
3101 * message queue. The size is approximate in that you shouldn't use
3102 * it to decide how many bytes to read off the network or anything
3103 * of that nature, as optimizations may choose to tell small white lies
3104 * to avoid performance overhead.
3106 * @param connection the connection
3107 * @returns the number of bytes that have been queued up but not sent
3110 dbus_connection_get_outgoing_size (DBusConnection *connection)
3114 _dbus_return_val_if_fail (connection != NULL, 0);
3116 CONNECTION_LOCK (connection);
3117 res = _dbus_counter_get_value (connection->outgoing_counter);
3118 CONNECTION_UNLOCK (connection);