From 5da911bce0310761514298444fde65d0a51ed85d Mon Sep 17 00:00:00 2001 From: Alexander Larsson Date: Thu, 20 Feb 2003 10:00:48 +0000 Subject: 2003-02-20 Alexander Larsson * dbus/dbus-transport-unix.c (unix_do_iteration): Unlock the connection mutex during a blocking select call. Add todo about how we need a way to wake up the select. * dbus/dbus-connection-internal.h: * dbus/dbus-connection.c: Add _dbus_connection_lock and _dbus_connection_unlock. --- dbus/dbus-transport-unix.c | 27 +++++++++++++++++++++++++-- 1 file changed, 25 insertions(+), 2 deletions(-) (limited to 'dbus/dbus-transport-unix.c') diff --git a/dbus/dbus-transport-unix.c b/dbus/dbus-transport-unix.c index c5dce8d7..b30dc1d6 100644 --- a/dbus/dbus-transport-unix.c +++ b/dbus/dbus-transport-unix.c @@ -884,6 +884,13 @@ unix_messages_pending (DBusTransport *transport, } /* FIXME use _dbus_poll(), not select() */ +/** + * @todo We need to have a way to wake up the select sleep if + * a new iteration request comes in with a flag (read/write) that + * we're not currently serving. Otherwise a call that just reads + * could block a write call forever (if there are no incoming + * messages). + */ static void unix_do_iteration (DBusTransport *transport, unsigned int flags, @@ -893,6 +900,7 @@ unix_do_iteration (DBusTransport *transport, fd_set read_set; fd_set write_set; dbus_bool_t do_select; + int select_res; _dbus_verbose (" iteration flags = %s%s timeout = %d\n", flags & DBUS_ITERATION_DO_READING ? "read" : "", @@ -984,9 +992,24 @@ unix_do_iteration (DBusTransport *transport, timeout.tv_usec = 0; use_timeout = TRUE; } + + /* For blocking selects we drop the connection lock here + * to avoid blocking out connection access during a potentially + * indefinite blocking call. The io path is still protected + * by the io_path_cond condvar, so we won't reenter this. + */ + if (flags & DBUS_ITERATION_BLOCK) + _dbus_connection_unlock (transport->connection); + + select_res = select (unix_transport->fd + 1, + &read_set, &write_set, &err_set, + use_timeout ? &timeout : NULL); + + if (flags & DBUS_ITERATION_BLOCK) + _dbus_connection_lock (transport->connection); + - if (select (unix_transport->fd + 1, &read_set, &write_set, &err_set, - use_timeout ? &timeout : NULL) >= 0) + if (select_res >= 0) { if (FD_ISSET (unix_transport->fd, &err_set)) do_io_error (transport); -- cgit