/*- * (MPSAFE) * * Copyright (c) 1982, 1986, 1991, 1993 * The Regents of the University of California. All rights reserved. * (c) UNIX System Laboratories, Inc. * All or some portions of this file are derived from material licensed * to the University of California by American Telephone and Telegraph * Co. or Unix System Laboratories, Inc. and are reproduced herein with * the permission of UNIX System Laboratories, Inc. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)tty_conf.c 8.4 (Berkeley) 1/21/94 * $FreeBSD: src/sys/kern/tty_conf.c,v 1.16.2.1 2002/03/11 01:14:55 dd Exp $ */ #include #include #include #include #ifndef MAXLDISC #define MAXLDISC 9 #endif static l_open_t l_noopen; static l_close_t l_noclose; static l_rint_t l_norint; static l_start_t l_nostart; /* * XXX it probably doesn't matter what the entries other than the l_open * entry are here. The l_nullioctl and ttymodem entries still look fishy. * Reconsider the removal of nullmodem anyway. It was too much like * ttymodem, but a completely null version might be useful. */ #define NODISC(n) \ { l_noopen, l_noclose, l_noread, l_nowrite, \ l_nullioctl, l_norint, l_nostart, ttymodem } struct linesw linesw[MAXLDISC] = { /* 0- termios */ { ttyopen, ttylclose, ttread, ttwrite, l_nullioctl, ttyinput, ttstart, ttymodem }, NODISC(1), /* 1- defunct */ NODISC(2), /* 2- NTTYDISC */ NODISC(3), /* loadable */ NODISC(4), /* SLIPDISC */ NODISC(5), /* PPPDISC */ NODISC(6), /* NETGRAPHDISC */ NODISC(7), /* loadable */ NODISC(8), /* loadable */ }; int nlinesw = NELEM(linesw); static struct linesw nodisc = NODISC(0); #define LOADABLE_LDISC 7 /* * ldisc_register: Register a line discipline. * * discipline: Index for discipline to load, or LDISC_LOAD for us to choose. * linesw_p: Pointer to linesw_p. * * Returns: Index used or -1 on failure. */ int ldisc_register(int discipline, struct linesw *linesw_p) { int slot = -1; lwkt_gettoken(&tty_token); if (discipline == LDISC_LOAD) { int i; for (i = LOADABLE_LDISC; i < MAXLDISC; i++) if (bcmp(linesw + i, &nodisc, sizeof(nodisc)) == 0) { slot = i; } } else if (discipline >= 0 && discipline < MAXLDISC) { slot = discipline; } if (slot != -1 && linesw_p) linesw[slot] = *linesw_p; lwkt_reltoken(&tty_token); return slot; } /* * ldisc_deregister: Deregister a line discipline obtained with * ldisc_register. * * discipline: Index for discipline to unload. */ void ldisc_deregister(int discipline) { lwkt_gettoken(&tty_token); if (discipline < MAXLDISC) { linesw[discipline] = nodisc; } lwkt_reltoken(&tty_token); } static int l_noopen(cdev_t dev, struct tty *tp) { return (ENODEV); } static int l_noclose(struct tty *tp, int flag) { return (ENODEV); } int l_noread(struct tty *tp, struct uio *uio, int flag) { return (ENODEV); } int l_nowrite(struct tty *tp, struct uio *uio, int flag) { return (ENODEV); } static int l_norint(int c, struct tty *tp) { return (ENODEV); } static int l_nostart(struct tty *tp) { return (ENODEV); } /* * Do nothing specific version of line * discipline specific ioctl command. */ int l_nullioctl(struct tty *tp, u_long cmd, char *data, int flags, struct ucred *cred) { return (ENOIOCTL); }