/* -*- mode: C; c-file-style: "gnu" -*- */ /* dbus-transport.c DBusTransport object (internal to D-BUS implementation) * * Copyright (C) 2002 Red Hat Inc. * * Licensed under the Academic Free License version 1.2 * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * */ #include "dbus-transport-protected.h" #include "dbus-transport-unix.h" #include "dbus-connection-internal.h" #include "dbus-watch.h" /** * @defgroup DBusTransport DBusTransport object * @ingroup DBusInternals * @brief "Backend" for a DBusConnection. * * Types and functions related to DBusTransport. A transport is an * abstraction that can send and receive data via various kinds of * network connections or other IPC mechanisms. * * @{ */ /** * @typedef DBusTransport * * Opaque object representing a way message stream. * DBusTransport abstracts various kinds of actual * transport mechanism, such as different network protocols, * or encryption schemes. */ /** * Initializes the base class members of DBusTransport. * Chained up to by subclasses in their constructor. * * @param transport the transport being created. * @param vtable the subclass vtable. * @returns #TRUE on success. */ dbus_bool_t _dbus_transport_init_base (DBusTransport *transport, const DBusTransportVTable *vtable) { DBusMessageLoader *loader; loader = _dbus_message_loader_new (); if (loader == NULL) return FALSE; transport->refcount = 1; transport->vtable = vtable; transport->loader = loader; return TRUE; } /** * Finalizes base class members of DBusTransport. * Chained up to from subclass finalizers. * * @param transport the transport. */ void _dbus_transport_finalize_base (DBusTransport *transport) { if (!transport->disconnected) _dbus_transport_disconnect (transport); _dbus_message_loader_unref (transport->loader); } /** * Opens a new transport for the given address. * * @todo right now the address is just a Unix domain socket path. * * @param address the address. * @param result location to store reason for failure. * @returns new transport of #NULL on failure. */ DBusTransport* _dbus_transport_open (const char *address, DBusResultCode *result) { DBusTransport *transport; /* FIXME parse the address - whatever format * we decide addresses are in - and find the * appropriate transport. */ /* Pretend it's just a unix domain socket name for now */ transport = _dbus_transport_new_for_domain_socket (address, result); return transport; } /** * Increments the reference count for the transport. * * @param transport the transport. */ void _dbus_transport_ref (DBusTransport *transport) { transport->refcount += 1; } /** * Decrements the reference count for the transport. * Disconnects and finalizes the transport if * the reference count reaches zero. * * @param transport the transport. */ void _dbus_transport_unref (DBusTransport *transport) { _dbus_assert (transport != NULL); _dbus_assert (transport->refcount > 0); transport->refcount -= 1; if (transport->refcount == 0) { _dbus_assert (transport->vtable->finalize != NULL); (* transport->vtable->finalize) (transport); } } /** * Closes our end of the connection to a remote application. Further * attempts to use this transport will fail. Only the first call to * _dbus_transport_disconnect() will have an effect. * * @param transport the transport. * */ void _dbus_transport_disconnect (DBusTransport *transport) { _dbus_assert (transport->vtable->disconnect != NULL); if (transport->disconnected) return; (* transport->vtable->disconnect) (transport); transport->disconnected = TRUE; } /** * Returns #TRUE if the transport has not been disconnected. * Disconnection can result from _dbus_transport_disconnect() * or because the server drops its end of the connection. * * @param transport the transport. */ dbus_bool_t _dbus_transport_get_is_connected (DBusTransport *transport) { return !transport->disconnected; } /** * Handles a watch by reading data, writing data, or disconnecting * the transport, as appropriate for the given condition. * * @param transport the transport. * @param watch the watch. * @param condition the current state of the watched file descriptor. */ void _dbus_transport_handle_watch (DBusTransport *transport, DBusWatch *watch, unsigned int condition) { _dbus_assert (transport->vtable->handle_watch != NULL); if (transport->disconnected) { _dbus_connection_transport_error (transport->connection, DBUS_RESULT_DISCONNECTED); return; } _dbus_watch_sanitize_condition (watch, &condition); (* transport->vtable->handle_watch) (transport, watch, condition); } /** * Sets the connection using this transport. Allows the transport * to add watches to the connection, queue incoming messages, * and pull outgoing messages. * * @param transport the transport. * @param connection the connection. */ void _dbus_transport_set_connection (DBusTransport *transport, DBusConnection *connection) { _dbus_assert (transport->vtable->connection_set != NULL); _dbus_assert (transport->connection == NULL); transport->connection = connection; (* transport->vtable->connection_set) (transport); } /** * Notifies the transport when the outgoing message queue goes from * empty to non-empty or vice versa. Typically causes the transport to * add or remove its DBUS_WATCH_WRITABLE watch. * * @param transport the transport. * @param queue_length the length of the outgoing message queue. * */ void _dbus_transport_messages_pending (DBusTransport *transport, int queue_length) { _dbus_assert (transport->vtable->messages_pending != NULL); if (transport->disconnected) { _dbus_connection_transport_error (transport->connection, DBUS_RESULT_DISCONNECTED); return; } (* transport->vtable->messages_pending) (transport, queue_length); } /** * Performs a single poll()/select() on the transport's file * descriptors and then reads/writes data as appropriate, * queueing incoming messages and sending outgoing messages. * This is the backend for _dbus_connection_do_iteration(). * See _dbus_connection_do_iteration() for full details. * * @param transport the transport. * @param flags indicates whether to read or write, and whether to block. * @param timeout_milliseconds if blocking, timeout or -1 for no timeout. */ void _dbus_transport_do_iteration (DBusTransport *transport, unsigned int flags, int timeout_milliseconds) { _dbus_assert (transport->vtable->do_iteration != NULL); if ((flags & (DBUS_ITERATION_DO_WRITING | DBUS_ITERATION_DO_READING)) == 0) return; /* Nothing to do */ if (transport->disconnected) { _dbus_connection_transport_error (transport->connection, DBUS_RESULT_DISCONNECTED); return; } (* transport->vtable->do_iteration) (transport, flags, timeout_milliseconds); } /** @} */