/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1982, 1986, 1991, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * 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.
 */

#include <sys/cdefs.h>
/*
 * mapping routines for old line discipline (yuck)
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/ioctl_compat.h>
#include <sys/tty.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>

struct speedtab {
        int sp_speed;                   /* Speed. */
        int sp_code;                    /* Code. */
};

static int ttcompatgetflags(struct tty *tp);
static void ttcompatsetflags(struct tty *tp, struct termios *t);
static void ttcompatsetlflags(struct tty *tp, struct termios *t);
static int ttcompatspeedtab(int speed, struct speedtab *table);

static int ttydebug = 0;
SYSCTL_INT(_debug, OID_AUTO, ttydebug, CTLFLAG_RW, &ttydebug, 0, "");

static struct speedtab compatspeeds[] = {
#define MAX_SPEED       17
        { 115200, 17 },
        { 57600, 16 },
        { 38400, 15 },
        { 19200, 14 },
        { 9600, 13 },
        { 4800, 12 },
        { 2400, 11 },
        { 1800, 10 },
        { 1200, 9 },
        { 600,  8 },
        { 300,  7 },
        { 200,  6 },
        { 150,  5 },
        { 134,  4 },
        { 110,  3 },
        { 75,   2 },
        { 50,   1 },
        { 0,    0 },
        { -1,   -1 },
};
static int compatspcodes[] = {
        0, 50, 75, 110, 134, 150, 200, 300, 600, 1200,
        1800, 2400, 4800, 9600, 19200, 38400, 57600, 115200,
};

static int
ttcompatspeedtab(int speed, struct speedtab *table)
{
        if (speed == 0)
                return (0); /* hangup */
        for ( ; table->sp_speed > 0; table++)
                if (table->sp_speed <= speed) /* nearest one, rounded down */
                        return (table->sp_code);
        return (1); /* 50, min and not hangup */
}

static int
ttsetcompat(struct tty *tp, u_long *com, caddr_t data, struct termios *term)
{
        switch (*com) {
        case TIOCSETP:
        case TIOCSETN: {
                struct sgttyb *sg = (struct sgttyb *)data;
                int speed;

                if ((speed = sg->sg_ispeed) > MAX_SPEED || speed < 0)
                        return(EINVAL);
                else if (speed != ttcompatspeedtab(tp->t_termios.c_ispeed,
                    compatspeeds))
                        term->c_ispeed = compatspcodes[speed];
                else
                        term->c_ispeed = tp->t_termios.c_ispeed;
                if ((speed = sg->sg_ospeed) > MAX_SPEED || speed < 0)
                        return(EINVAL);
                else if (speed != ttcompatspeedtab(tp->t_termios.c_ospeed,
                    compatspeeds))
                        term->c_ospeed = compatspcodes[speed];
                else
                        term->c_ospeed = tp->t_termios.c_ospeed;
                term->c_cc[VERASE] = sg->sg_erase;
                term->c_cc[VKILL] = sg->sg_kill;
                tp->t_compatflags = (tp->t_compatflags&0xffff0000) |
                    (sg->sg_flags&0xffff);
                ttcompatsetflags(tp, term);
                *com = (*com == TIOCSETP) ? TIOCSETAF : TIOCSETA;
                break;
        }
        case TIOCSETC: {
                struct tchars *tc = (struct tchars *)data;
                cc_t *cc;

                cc = term->c_cc;
                cc[VINTR] = tc->t_intrc;
                cc[VQUIT] = tc->t_quitc;
                cc[VSTART] = tc->t_startc;
                cc[VSTOP] = tc->t_stopc;
                cc[VEOF] = tc->t_eofc;
                cc[VEOL] = tc->t_brkc;
                if (tc->t_brkc == (char)_POSIX_VDISABLE)
                        cc[VEOL2] = _POSIX_VDISABLE;
                *com = TIOCSETA;
                break;
        }
        case TIOCSLTC: {
                struct ltchars *ltc = (struct ltchars *)data;
                cc_t *cc;

                cc = term->c_cc;
                cc[VSUSP] = ltc->t_suspc;
                cc[VDSUSP] = ltc->t_dsuspc;
                cc[VREPRINT] = ltc->t_rprntc;
                cc[VDISCARD] = ltc->t_flushc;
                cc[VWERASE] = ltc->t_werasc;
                cc[VLNEXT] = ltc->t_lnextc;
                *com = TIOCSETA;
                break;
        }
        case TIOCLBIS:
        case TIOCLBIC:
        case TIOCLSET:
                if (*com == TIOCLSET)
                        tp->t_compatflags = (tp->t_compatflags&0xffff) |
                            *(int *)data<<16;
                else {
                        tp->t_compatflags = (ttcompatgetflags(tp)&0xffff0000) |
                            (tp->t_compatflags&0xffff);
                        if (*com == TIOCLBIS)
                                tp->t_compatflags |= *(int *)data<<16;
                        else
                                tp->t_compatflags &= ~(*(int *)data<<16);
                }
                ttcompatsetlflags(tp, term);
                *com = TIOCSETA;
                break;
        }
        return 0;
}

/*ARGSUSED*/
int
tty_ioctl_compat(struct tty *tp, u_long com, caddr_t data, int fflag,
    struct thread *td)
{
        switch (com) {
        case TIOCSETP:
        case TIOCSETN:
        case TIOCSETC:
        case TIOCSLTC:
        case TIOCLBIS:
        case TIOCLBIC:
        case TIOCLSET: {
                struct termios term;
                int error;

                term = tp->t_termios;
                if ((error = ttsetcompat(tp, &com, data, &term)) != 0)
                        return error;
                return tty_ioctl(tp, com, &term, fflag, td);
        }
        case TIOCGETP: {
                struct sgttyb *sg = (struct sgttyb *)data;
                cc_t *cc = tp->t_termios.c_cc;

                sg->sg_ospeed = ttcompatspeedtab(tp->t_termios.c_ospeed,
                    compatspeeds);
                if (tp->t_termios.c_ispeed == 0)
                        sg->sg_ispeed = sg->sg_ospeed;
                else
                        sg->sg_ispeed = ttcompatspeedtab(tp->t_termios.c_ispeed,
                            compatspeeds);
                sg->sg_erase = cc[VERASE];
                sg->sg_kill = cc[VKILL];
                sg->sg_flags = tp->t_compatflags = ttcompatgetflags(tp);
                break;
        }
        case TIOCGETC: {
                struct tchars *tc = (struct tchars *)data;
                cc_t *cc = tp->t_termios.c_cc;

                tc->t_intrc = cc[VINTR];
                tc->t_quitc = cc[VQUIT];
                tc->t_startc = cc[VSTART];
                tc->t_stopc = cc[VSTOP];
                tc->t_eofc = cc[VEOF];
                tc->t_brkc = cc[VEOL];
                break;
        }
        case TIOCGLTC: {
                struct ltchars *ltc = (struct ltchars *)data;
                cc_t *cc = tp->t_termios.c_cc;

                ltc->t_suspc = cc[VSUSP];
                ltc->t_dsuspc = cc[VDSUSP];
                ltc->t_rprntc = cc[VREPRINT];
                ltc->t_flushc = cc[VDISCARD];
                ltc->t_werasc = cc[VWERASE];
                ltc->t_lnextc = cc[VLNEXT];
                break;
        }
        case TIOCLGET:
                tp->t_compatflags =
                 (ttcompatgetflags(tp) & 0xffff0000UL)
                   | (tp->t_compatflags & 0xffff);
                *(int *)data = tp->t_compatflags>>16;
                if (ttydebug)
                        printf("CLGET: returning %x\n", *(int *)data);
                break;

        case OTIOCGETD:
                *(int *)data = 2;
                break;

        case OTIOCSETD: {
                int ldisczero = 0;

                return (tty_ioctl(tp, TIOCSETD,
                        *(int *)data == 2 ? (caddr_t)&ldisczero : data,
                        fflag, td));
            }

        case OTIOCCONS: {
                int one = 1;

                return (tty_ioctl(tp, TIOCCONS, (caddr_t)&one, fflag, td));
        }

        default:
                return (ENOIOCTL);
        }
        return (0);
}

static int
ttcompatgetflags(struct tty *tp)
{
        tcflag_t iflag  = tp->t_termios.c_iflag;
        tcflag_t lflag  = tp->t_termios.c_lflag;
        tcflag_t oflag  = tp->t_termios.c_oflag;
        tcflag_t cflag  = tp->t_termios.c_cflag;
        int flags = 0;

        if (iflag&IXOFF)
                flags |= TANDEM;
        if (iflag&ICRNL || oflag&ONLCR)
                flags |= CRMOD;
        if ((cflag&CSIZE) == CS8) {
                flags |= PASS8;
                if (iflag&ISTRIP)
                        flags |= ANYP;
        }
        else if (cflag&PARENB) {
                if (iflag&INPCK) {
                        if (cflag&PARODD)
                                flags |= ODDP;
                        else
                                flags |= EVENP;
                } else
                        flags |= EVENP | ODDP;
        }

        if ((lflag&ICANON) == 0) {
                /* fudge */
                if (iflag&(INPCK|ISTRIP|IXON) || lflag&(IEXTEN|ISIG)
                    || (cflag&(CSIZE|PARENB)) != CS8)
                        flags |= CBREAK;
                else
                        flags |= RAW;
        }
        if (!(flags&RAW) && !(oflag&OPOST) && (cflag&(CSIZE|PARENB)) == CS8)
                flags |= LITOUT;
        if (cflag&MDMBUF)
                flags |= MDMBUF;
        if ((cflag&HUPCL) == 0)
                flags |= NOHANG;
        if (oflag&TAB3)
                flags |= XTABS;
        if (lflag&ECHOE)
                flags |= CRTERA|CRTBS;
        if (lflag&ECHOKE)
                flags |= CRTKIL|CRTBS;
        if (lflag&ECHOPRT)
                flags |= PRTERA;
        if (lflag&ECHOCTL)
                flags |= CTLECH;
        if ((iflag&IXANY) == 0)
                flags |= DECCTQ;
        flags |= lflag&(ECHO|TOSTOP|FLUSHO|PENDIN|NOFLSH);
        if (ttydebug)
                printf("getflags: %x\n", flags);
        return (flags);
}

static void
ttcompatsetflags(struct tty *tp, struct termios *t)
{
        int flags = tp->t_compatflags;
        tcflag_t iflag  = t->c_iflag;
        tcflag_t oflag  = t->c_oflag;
        tcflag_t lflag  = t->c_lflag;
        tcflag_t cflag  = t->c_cflag;

        if (flags & RAW) {
                iflag = IGNBRK;
                lflag &= ~(ECHOCTL|ISIG|ICANON|IEXTEN);
        } else {
                iflag &= ~(PARMRK|IGNPAR|IGNCR|INLCR);
                iflag |= BRKINT|IXON|IMAXBEL;
                lflag |= ISIG|IEXTEN|ECHOCTL;   /* XXX was echoctl on ? */
                if (flags & XTABS)
                        oflag |= TAB3;
                else
                        oflag &= ~TAB3;
                if (flags & CBREAK)
                        lflag &= ~ICANON;
                else
                        lflag |= ICANON;
                if (flags&CRMOD) {
                        iflag |= ICRNL;
                        oflag |= ONLCR;
                } else {
                        iflag &= ~ICRNL;
                        oflag &= ~ONLCR;
                }
        }
        if (flags&ECHO)
                lflag |= ECHO;
        else
                lflag &= ~ECHO;

        cflag &= ~(CSIZE|PARENB);
        if (flags&(RAW|LITOUT|PASS8)) {
                cflag |= CS8;
                if (!(flags&(RAW|PASS8))
                    || (flags&(RAW|PASS8|ANYP)) == (PASS8|ANYP))
                        iflag |= ISTRIP;
                else
                        iflag &= ~ISTRIP;
                if (flags&(RAW|LITOUT))
                        oflag &= ~OPOST;
                else
                        oflag |= OPOST;
        } else {
                cflag |= CS7|PARENB;
                iflag |= ISTRIP;
                oflag |= OPOST;
        }
        /* XXX don't set INPCK if RAW or PASS8? */
        if ((flags&(EVENP|ODDP)) == EVENP) {
                iflag |= INPCK;
                cflag &= ~PARODD;
        } else if ((flags&(EVENP|ODDP)) == ODDP) {
                iflag |= INPCK;
                cflag |= PARODD;
        } else
                iflag &= ~INPCK;
        if (flags&TANDEM)
                iflag |= IXOFF;
        else
                iflag &= ~IXOFF;
        if ((flags&DECCTQ) == 0)
                iflag |= IXANY;
        else
                iflag &= ~IXANY;
        t->c_iflag = iflag;
        t->c_oflag = oflag;
        t->c_lflag = lflag;
        t->c_cflag = cflag;
}

static void
ttcompatsetlflags(struct tty *tp, struct termios *t)
{
        int flags = tp->t_compatflags;
        tcflag_t iflag  = t->c_iflag;
        tcflag_t oflag  = t->c_oflag;
        tcflag_t lflag  = t->c_lflag;
        tcflag_t cflag  = t->c_cflag;

        iflag &= ~(PARMRK|IGNPAR|IGNCR|INLCR);
        if (flags&CRTERA)
                lflag |= ECHOE;
        else
                lflag &= ~ECHOE;
        if (flags&CRTKIL)
                lflag |= ECHOKE;
        else
                lflag &= ~ECHOKE;
        if (flags&PRTERA)
                lflag |= ECHOPRT;
        else
                lflag &= ~ECHOPRT;
        if (flags&CTLECH)
                lflag |= ECHOCTL;
        else
                lflag &= ~ECHOCTL;
        if (flags&TANDEM)
                iflag |= IXOFF;
        else
                iflag &= ~IXOFF;
        if ((flags&DECCTQ) == 0)
                iflag |= IXANY;
        else
                iflag &= ~IXANY;
        if (flags & MDMBUF)
                cflag |= MDMBUF;
        else
                cflag &= ~MDMBUF;
        if (flags&NOHANG)
                cflag &= ~HUPCL;
        else
                cflag |= HUPCL;
        lflag &= ~(TOSTOP|FLUSHO|PENDIN|NOFLSH);
        lflag |= flags&(TOSTOP|FLUSHO|PENDIN|NOFLSH);

        /*
         * The next if-else statement is copied from above so don't bother
         * checking it separately.  We could avoid fiddlling with the
         * character size if the mode is already RAW or if neither the
         * LITOUT bit or the PASS8 bit is being changed, but the delta of
         * the change is not available here and skipping the RAW case would
         * make the code different from above.
         */
        cflag &= ~(CSIZE|PARENB);
        if (flags&(RAW|LITOUT|PASS8)) {
                cflag |= CS8;
                if (!(flags&(RAW|PASS8))
                    || (flags&(RAW|PASS8|ANYP)) == (PASS8|ANYP))
                        iflag |= ISTRIP;
                else
                        iflag &= ~ISTRIP;
                if (flags&(RAW|LITOUT))
                        oflag &= ~OPOST;
                else
                        oflag |= OPOST;
        } else {
                cflag |= CS7|PARENB;
                iflag |= ISTRIP;
                oflag |= OPOST;
        }
        t->c_iflag = iflag;
        t->c_oflag = oflag;
        t->c_lflag = lflag;
        t->c_cflag = cflag;
}