1 /* -*- mode: C; c-file-style: "gnu" -*- */
2 /* dbus-transport.c DBusTransport object (internal to D-BUS implementation)
4 * Copyright (C) 2002 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
24 #include "dbus-transport-protected.h"
25 #include "dbus-transport-unix.h"
26 #include "dbus-connection-internal.h"
27 #include "dbus-watch.h"
28 #include "dbus-auth.h"
31 * @defgroup DBusTransport DBusTransport object
32 * @ingroup DBusInternals
33 * @brief "Backend" for a DBusConnection.
35 * Types and functions related to DBusTransport. A transport is an
36 * abstraction that can send and receive data via various kinds of
37 * network connections or other IPC mechanisms.
43 * @typedef DBusTransport
45 * Opaque object representing a way message stream.
46 * DBusTransport abstracts various kinds of actual
47 * transport mechanism, such as different network protocols,
48 * or encryption schemes.
52 * Refs a transport and associated connection for reentrancy.
54 * @todo this macro reflects a design mistake, which is that the
55 * transport has a pointer to its connection. Ownership should move in
56 * only one direction; the connection should push/pull from the
57 * transport, rather than vice versa. Then the connection would take
58 * care of referencing itself when needed.
60 #define DBUS_TRANSPORT_HOLD_REF(t) \
61 _dbus_transport_ref (t); if ((t)->connection) dbus_connection_ref ((t)->connection)
64 * Inverse of DBUS_TRANSPORT_HOLD_REF().
66 #define DBUS_TRANSPORT_RELEASE_REF(t) \
67 if ((t)->connection) dbus_connection_unref ((t)->connection); _dbus_transport_unref (t)
71 * Initializes the base class members of DBusTransport.
72 * Chained up to by subclasses in their constructor.
74 * @param transport the transport being created.
75 * @param vtable the subclass vtable.
76 * @param server #TRUE if this transport is on the server side of a connection
77 * @returns #TRUE on success.
80 _dbus_transport_init_base (DBusTransport *transport,
81 const DBusTransportVTable *vtable,
84 DBusMessageLoader *loader;
87 loader = _dbus_message_loader_new ();
92 auth = _dbus_auth_server_new ();
94 auth = _dbus_auth_client_new ();
97 _dbus_message_loader_unref (loader);
101 transport->refcount = 1;
102 transport->vtable = vtable;
103 transport->loader = loader;
104 transport->auth = auth;
105 transport->authenticated = FALSE;
106 transport->messages_need_sending = FALSE;
107 transport->disconnected = FALSE;
113 * Finalizes base class members of DBusTransport.
114 * Chained up to from subclass finalizers.
116 * @param transport the transport.
119 _dbus_transport_finalize_base (DBusTransport *transport)
121 if (!transport->disconnected)
122 _dbus_transport_disconnect (transport);
124 _dbus_message_loader_unref (transport->loader);
125 _dbus_auth_unref (transport->auth);
129 * Opens a new transport for the given address. (This opens a
130 * client-side-of-the-connection transport.)
132 * @todo right now the address is just a Unix domain socket path.
134 * @param address the address.
135 * @param result location to store reason for failure.
136 * @returns new transport of #NULL on failure.
139 _dbus_transport_open (const char *address,
140 DBusResultCode *result)
142 DBusTransport *transport;
144 /* FIXME parse the address - whatever format
145 * we decide addresses are in - and find the
146 * appropriate transport.
149 /* Pretend it's just a unix domain socket name for now */
150 transport = _dbus_transport_new_for_domain_socket (address,
158 * Increments the reference count for the transport.
160 * @param transport the transport.
163 _dbus_transport_ref (DBusTransport *transport)
165 transport->refcount += 1;
169 * Decrements the reference count for the transport.
170 * Disconnects and finalizes the transport if
171 * the reference count reaches zero.
173 * @param transport the transport.
176 _dbus_transport_unref (DBusTransport *transport)
178 _dbus_assert (transport != NULL);
179 _dbus_assert (transport->refcount > 0);
181 transport->refcount -= 1;
182 if (transport->refcount == 0)
184 _dbus_assert (transport->vtable->finalize != NULL);
186 (* transport->vtable->finalize) (transport);
191 * Closes our end of the connection to a remote application. Further
192 * attempts to use this transport will fail. Only the first call to
193 * _dbus_transport_disconnect() will have an effect.
195 * @param transport the transport.
199 _dbus_transport_disconnect (DBusTransport *transport)
201 _dbus_assert (transport->vtable->disconnect != NULL);
203 if (transport->disconnected)
206 DBUS_TRANSPORT_HOLD_REF (transport);
207 (* transport->vtable->disconnect) (transport);
209 transport->disconnected = TRUE;
210 DBUS_TRANSPORT_RELEASE_REF (transport);
214 * Returns #TRUE if the transport has not been disconnected.
215 * Disconnection can result from _dbus_transport_disconnect()
216 * or because the server drops its end of the connection.
218 * @param transport the transport.
219 * @returns whether we're connected
222 _dbus_transport_get_is_connected (DBusTransport *transport)
224 return !transport->disconnected;
228 * Returns #TRUE if we have been authenticated. Will return #TRUE
229 * even if the transport is disconnected.
231 * @param transport the transport
232 * @returns whether we're authenticated
235 _dbus_transport_get_is_authenticated (DBusTransport *transport)
237 if (transport->authenticated)
241 transport->authenticated =
242 _dbus_auth_do_work (transport->auth) == DBUS_AUTH_STATE_AUTHENTICATED;
244 return transport->authenticated;
249 * Handles a watch by reading data, writing data, or disconnecting
250 * the transport, as appropriate for the given condition.
252 * @param transport the transport.
253 * @param watch the watch.
254 * @param condition the current state of the watched file descriptor.
257 _dbus_transport_handle_watch (DBusTransport *transport,
259 unsigned int condition)
261 _dbus_assert (transport->vtable->handle_watch != NULL);
263 if (transport->disconnected)
265 _dbus_connection_transport_error (transport->connection,
266 DBUS_RESULT_DISCONNECTED);
270 if (dbus_watch_get_fd (watch) < 0)
272 _dbus_warn ("Tried to handle an invalidated watch; this watch should have been removed\n");
276 _dbus_watch_sanitize_condition (watch, &condition);
278 DBUS_TRANSPORT_HOLD_REF (transport);
279 _dbus_watch_ref (watch);
280 (* transport->vtable->handle_watch) (transport, watch, condition);
281 _dbus_watch_unref (watch);
282 DBUS_TRANSPORT_RELEASE_REF (transport);
286 * Sets the connection using this transport. Allows the transport
287 * to add watches to the connection, queue incoming messages,
288 * and pull outgoing messages.
290 * @param transport the transport.
291 * @param connection the connection.
294 _dbus_transport_set_connection (DBusTransport *transport,
295 DBusConnection *connection)
297 _dbus_assert (transport->vtable->connection_set != NULL);
298 _dbus_assert (transport->connection == NULL);
300 transport->connection = connection;
302 DBUS_TRANSPORT_HOLD_REF (transport);
303 (* transport->vtable->connection_set) (transport);
304 DBUS_TRANSPORT_RELEASE_REF (transport);
308 * Notifies the transport when the outgoing message queue goes from
309 * empty to non-empty or vice versa. Typically causes the transport to
310 * add or remove its DBUS_WATCH_WRITABLE watch.
312 * @param transport the transport.
313 * @param queue_length the length of the outgoing message queue.
317 _dbus_transport_messages_pending (DBusTransport *transport,
320 _dbus_assert (transport->vtable->messages_pending != NULL);
322 if (transport->disconnected)
324 _dbus_connection_transport_error (transport->connection,
325 DBUS_RESULT_DISCONNECTED);
329 transport->messages_need_sending = queue_length > 0;
331 DBUS_TRANSPORT_HOLD_REF (transport);
332 (* transport->vtable->messages_pending) (transport,
334 DBUS_TRANSPORT_RELEASE_REF (transport);
338 * Performs a single poll()/select() on the transport's file
339 * descriptors and then reads/writes data as appropriate,
340 * queueing incoming messages and sending outgoing messages.
341 * This is the backend for _dbus_connection_do_iteration().
342 * See _dbus_connection_do_iteration() for full details.
344 * @param transport the transport.
345 * @param flags indicates whether to read or write, and whether to block.
346 * @param timeout_milliseconds if blocking, timeout or -1 for no timeout.
349 _dbus_transport_do_iteration (DBusTransport *transport,
351 int timeout_milliseconds)
353 _dbus_assert (transport->vtable->do_iteration != NULL);
355 if ((flags & (DBUS_ITERATION_DO_WRITING |
356 DBUS_ITERATION_DO_READING)) == 0)
357 return; /* Nothing to do */
359 if (transport->disconnected)
361 _dbus_connection_transport_error (transport->connection,
362 DBUS_RESULT_DISCONNECTED);
366 DBUS_TRANSPORT_HOLD_REF (transport);
367 (* transport->vtable->do_iteration) (transport, flags,
368 timeout_milliseconds);
369 DBUS_TRANSPORT_RELEASE_REF (transport);