/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1983, 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.
 */

/*
 * Melbourne getty.
 */
#include <sys/ioctl.h>
#include <sys/param.h>
#include <sys/time.h>

#include <poll.h>
#include <regex.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <termios.h>
#include <unistd.h>

#include "gettytab.h"
#include "pathnames.h"
#include "extern.h"

/*
 * Get a table entry.
 */
void
gettable(const char *name)
{
        char *buf = NULL;
        struct gettystrs *sp;
        struct gettynums *np;
        struct gettyflags *fp;
        long n;
        int l;
        char *p;
        static char path_gettytab[PATH_MAX];
        char *dba[2];

        static int firsttime = 1;

        strlcpy(path_gettytab, _PATH_GETTYTAB, sizeof(path_gettytab));
        dba[0] = path_gettytab;
        dba[1] = NULL;

        if (firsttime) {
                /*
                 * we need to strdup() anything in the strings array
                 * initially in order to simplify things later
                 */
                for (sp = gettystrs; sp->field; sp++)
                        if (sp->value != NULL) {
                                /* handle these ones more carefully */
                                if (sp >= &gettystrs[4] && sp <= &gettystrs[6])
                                        l = 2;
                                else
                                        l = strlen(sp->value) + 1;
                                if ((p = malloc(l)) != NULL)
                                        strlcpy(p, sp->value, l);
                                /*
                                 * replace, even if NULL, else we'll
                                 * have problems with free()ing static mem
                                 */
                                sp->value = p;
                        }
                firsttime = 0;
        }

        switch (cgetent(&buf, dba, name)) {
        case 1:
                syslog(LOG_ERR, "getty: couldn't resolve 'tc=' in gettytab '%s'", name);
                return;
        case 0:
                break;
        case -1:
                syslog(LOG_ERR, "getty: unknown gettytab entry '%s'", name);
                return;
        case -2:
                syslog(LOG_ERR, "getty: retrieving gettytab entry '%s': %m", name);
                return;
        case -3:
                syslog(LOG_ERR, "getty: recursive 'tc=' reference gettytab entry '%s'", name);
                return;
        default:
                syslog(LOG_ERR, "getty: unexpected cgetent() error for entry '%s'", name);
                return;
        }

        for (sp = gettystrs; sp->field; sp++) {
                if ((l = cgetstr(buf, sp->field, &p)) >= 0) {
                        if (sp->value) {
                                /* prefer existing value */
                                if (strcmp(p, sp->value) != 0)
                                        free(sp->value);
                                else {
                                        free(p);
                                        p = sp->value;
                                }
                        }
                        sp->value = p;
                } else if (l == -1) {
                        free(sp->value);
                        sp->value = NULL;
                }
        }

        for (np = gettynums; np->field; np++) {
                if (cgetnum(buf, np->field, &n) == -1)
                        np->set = 0;
                else {
                        np->set = 1;
                        np->value = n;
                }
        }

        for (fp = gettyflags; fp->field; fp++) {
                if (cgetcap(buf, fp->field, ':') == NULL)
                        fp->set = 0;
                else {
                        fp->set = 1;
                        fp->value = 1 ^ fp->invrt;
                }
        }
        free(buf);
}

void
gendefaults(void)
{
        struct gettystrs *sp;
        struct gettynums *np;
        struct gettyflags *fp;

        for (sp = gettystrs; sp->field; sp++)
                if (sp->value)
                        sp->defalt = strdup(sp->value);
        for (np = gettynums; np->field; np++)
                if (np->set)
                        np->defalt = np->value;
        for (fp = gettyflags; fp->field; fp++)
                if (fp->set)
                        fp->defalt = fp->value;
                else
                        fp->defalt = fp->invrt;
}

void
setdefaults(void)
{
        struct gettystrs *sp;
        struct gettynums *np;
        struct gettyflags *fp;

        for (sp = gettystrs; sp->field; sp++)
                if (!sp->value)
                        sp->value = !sp->defalt ?
                            sp->defalt : strdup(sp->defalt);
        for (np = gettynums; np->field; np++)
                if (!np->set)
                        np->value = np->defalt;
        for (fp = gettyflags; fp->field; fp++)
                if (!fp->set)
                        fp->value = fp->defalt;
}

static char **
charnames[] = {
        &ER, &KL, &IN, &QU, &XN, &XF, &ET, &BK,
        &SU, &DS, &RP, &FL, &WE, &LN, 0
};

#define CV(a) (char *)(&tmode.c_cc[a])

static char *
charvars[] = {
        CV(VERASE), CV(VKILL), CV(VINTR),
        CV(VQUIT), CV(VSTART), CV(VSTOP),
        CV(VEOF), CV(VEOL), CV(VSUSP),
        CV(VDSUSP), CV(VREPRINT), CV(VDISCARD),
        CV(VWERASE), CV(VLNEXT), 0
};

void
setchars(void)
{
        int i;
        const char *p;

        for (i = 0; charnames[i]; i++) {
                p = *charnames[i];
                if (p && *p)
                        *charvars[i] = *p;
                else
                        *charvars[i] = _POSIX_VDISABLE;
        }
}

/* Macros to clear/set/test flags. */
#define SET(t, f)       (t) |= (f)
#define CLR(t, f)       (t) &= ~(f)
#define ISSET(t, f)     ((t) & (f))

void
set_flags(int n)
{
        tcflag_t iflag, oflag, cflag, lflag;


        switch (n) {
        case 0:
                if (C0set && I0set && L0set && O0set) {
                        tmode.c_cflag = C0;
                        tmode.c_iflag = I0;
                        tmode.c_lflag = L0;
                        tmode.c_oflag = O0;
                        return;
                }
                break;
        case 1:
                if (C1set && I1set && L1set && O1set) {
                        tmode.c_cflag = C1;
                        tmode.c_iflag = I1;
                        tmode.c_lflag = L1;
                        tmode.c_oflag = O1;
                        return;
                }
                break;
        default:
                if (C2set && I2set && L2set && O2set) {
                        tmode.c_cflag = C2;
                        tmode.c_iflag = I2;
                        tmode.c_lflag = L2;
                        tmode.c_oflag = O2;
                        return;
                }
                break;
        }

        iflag = omode.c_iflag;
        oflag = omode.c_oflag;
        cflag = omode.c_cflag;
        lflag = omode.c_lflag;

        if (NP) {
                CLR(cflag, CSIZE|PARENB);
                SET(cflag, CS8);
                CLR(iflag, ISTRIP|INPCK|IGNPAR);
        } else if (AP || EP || OP) {
                CLR(cflag, CSIZE);
                SET(cflag, CS7|PARENB);
                SET(iflag, ISTRIP);
                if (OP && !EP) {
                        SET(iflag, INPCK|IGNPAR);
                        SET(cflag, PARODD);
                        if (AP)
                                CLR(iflag, INPCK);
                } else if (EP && !OP) {
                        SET(iflag, INPCK|IGNPAR);
                        CLR(cflag, PARODD);
                        if (AP)
                                CLR(iflag, INPCK);
                } else if (AP || (EP && OP)) {
                        CLR(iflag, INPCK|IGNPAR);
                        CLR(cflag, PARODD);
                }
        } /* else, leave as is */

#if 0
        if (UC)
                f |= LCASE;
#endif

        if (HC)
                SET(cflag, HUPCL);
        else
                CLR(cflag, HUPCL);

        if (MB)
                SET(cflag, MDMBUF);
        else
                CLR(cflag, MDMBUF);

        if (HW)
                SET(cflag, CRTSCTS);
        else
                CLR(cflag, CRTSCTS);

        if (NL) {
                SET(iflag, ICRNL);
                SET(oflag, ONLCR|OPOST);
        } else {
                CLR(iflag, ICRNL);
                CLR(oflag, ONLCR);
        }

        if (!HT)
                SET(oflag, OXTABS|OPOST);
        else
                CLR(oflag, OXTABS);

#ifdef XXX_DELAY
        SET(f, delaybits());
#endif

        if (n == 1) {           /* read mode flags */
                if (RW) {
                        iflag = 0;
                        CLR(oflag, OPOST);
                        CLR(cflag, CSIZE|PARENB);
                        SET(cflag, CS8);
                        lflag = 0;
                } else {
                        CLR(lflag, ICANON);
                }
                goto out;
        }

        if (n == 0)
                goto out;

#if 0
        if (CB)
                SET(f, CRTBS);
#endif

        if (CE)
                SET(lflag, ECHOE);
        else
                CLR(lflag, ECHOE);

        if (CK)
                SET(lflag, ECHOKE);
        else
                CLR(lflag, ECHOKE);

        if (PE)
                SET(lflag, ECHOPRT);
        else
                CLR(lflag, ECHOPRT);

        if (EC)
                SET(lflag, ECHO);
        else
                CLR(lflag, ECHO);

        if (XC)
                SET(lflag, ECHOCTL);
        else
                CLR(lflag, ECHOCTL);

        if (DX)
                SET(lflag, IXANY);
        else
                CLR(lflag, IXANY);

out:
        tmode.c_iflag = iflag;
        tmode.c_oflag = oflag;
        tmode.c_cflag = cflag;
        tmode.c_lflag = lflag;
}


#ifdef XXX_DELAY
struct delayval {
        unsigned        delay;          /* delay in ms */
        int             bits;
};

/*
 * below are random guesses, I can't be bothered checking
 */

struct delayval crdelay[] = {
        { 1,            CR1 },
        { 2,            CR2 },
        { 3,            CR3 },
        { 83,           CR1 },
        { 166,          CR2 },
        { 0,            CR3 },
};

struct delayval nldelay[] = {
        { 1,            NL1 },          /* special, calculated */
        { 2,            NL2 },
        { 3,            NL3 },
        { 100,          NL2 },
        { 0,            NL3 },
};

struct delayval bsdelay[] = {
        { 1,            BS1 },
        { 0,            0 },
};

struct delayval ffdelay[] = {
        { 1,            FF1 },
        { 1750,         FF1 },
        { 0,            FF1 },
};

struct delayval tbdelay[] = {
        { 1,            TAB1 },
        { 2,            TAB2 },
        { 3,            XTABS },        /* this is expand tabs */
        { 100,          TAB1 },
        { 0,            TAB2 },
};

int
delaybits(void)
{
        int f;

        f  = adelay(CD, crdelay);
        f |= adelay(ND, nldelay);
        f |= adelay(FD, ffdelay);
        f |= adelay(TD, tbdelay);
        f |= adelay(BD, bsdelay);
        return (f);
}

int
adelay(int ms, struct delayval *dp)
{
        if (ms == 0)
                return (0);
        while (dp->delay && ms > dp->delay)
                dp++;
        return (dp->bits);
}
#endif

char    editedhost[MAXHOSTNAMELEN];

void
edithost(const char *pattern)
{
        regex_t regex;
        regmatch_t *match;
        int found;

        if (pattern == NULL || *pattern == '\0')
                goto copyasis;
        if (regcomp(&regex, pattern, REG_EXTENDED) != 0)
                goto copyasis;

        match = calloc(regex.re_nsub + 1, sizeof(*match));
        if (match == NULL) {
                regfree(&regex);
                goto copyasis;
        }

        found = !regexec(&regex, HN, regex.re_nsub + 1, match, 0);
        if (found) {
                size_t subex, totalsize;

                /*
                 * We found a match.  If there were no parenthesized
                 * subexpressions in the pattern, use entire matched
                 * string as ``editedhost''; otherwise use the first
                 * matched subexpression.
                 */
                subex = !!regex.re_nsub;
                totalsize = match[subex].rm_eo - match[subex].rm_so + 1;
                strlcpy(editedhost, HN + match[subex].rm_so, totalsize >
                    sizeof(editedhost) ? sizeof(editedhost) : totalsize);
        }
        free(match);
        regfree(&regex);
        if (found)
                return;
        /*
         * In case of any errors, or if the pattern did not match, pass
         * the original hostname as is.
         */
copyasis:
        strlcpy(editedhost, HN, sizeof(editedhost));
}

static struct speedtab {
        int     speed;
        int     uxname;
} speedtab[] = {
        { 50,   B50 },
        { 75,   B75 },
        { 110,  B110 },
        { 134,  B134 },
        { 150,  B150 },
        { 200,  B200 },
        { 300,  B300 },
        { 600,  B600 },
        { 1200, B1200 },
        { 1800, B1800 },
        { 2400, B2400 },
        { 4800, B4800 },
        { 9600, B9600 },
        { 19200, EXTA },
        { 19,   EXTA },         /* for people who say 19.2K */
        { 38400, EXTB },
        { 38,   EXTB },
        { 7200, EXTB },         /* alternative */
        { 57600, B57600 },
        { 115200, B115200 },
        { 230400, B230400 },
        { 0, 0 }
};

int
speed(int val)
{
        struct speedtab *sp;

        if (val <= B230400)
                return (val);

        for (sp = speedtab; sp->speed; sp++)
                if (sp->speed == val)
                        return (sp->uxname);

        return (B300);          /* default in impossible cases */
}

void
makeenv(char *env[])
{
        static char termbuf[128] = "TERM=";
        char *p, *q;
        char **ep;

        ep = env;
        if (TT && *TT) {
                strlcat(termbuf, TT, sizeof(termbuf));
                *ep++ = termbuf;
        }
        if ((p = EV)) {
                q = p;
                while ((q = strchr(q, ','))) {
                        *q++ = '\0';
                        *ep++ = p;
                        p = q;
                }
                if (*p)
                        *ep++ = p;
        }
        *ep = (char *)0;
}

/*
 * This speed select mechanism is written for the Develcon DATASWITCH.
 * The Develcon sends a string of the form "B{speed}\n" at a predefined
 * baud rate. This string indicates the user's actual speed.
 * The routine below returns the terminal type mapped from derived speed.
 */
static struct   portselect {
        const char      *ps_baud;
        const char      *ps_type;
} portspeeds[] = {
        { "B110",       "std.110" },
        { "B134",       "std.134" },
        { "B150",       "std.150" },
        { "B300",       "std.300" },
        { "B600",       "std.600" },
        { "B1200",      "std.1200" },
        { "B2400",      "std.2400" },
        { "B4800",      "std.4800" },
        { "B9600",      "std.9600" },
        { "B19200",     "std.19200" },
        { NULL, NULL }
};

const char *
portselector(void)
{
        char c, baud[20];
        const char *type = "default";
        struct portselect *ps;
        size_t len;

        alarm(5*60);
        for (len = 0; len < sizeof (baud) - 1; len++) {
                if (read(STDIN_FILENO, &c, 1) <= 0)
                        break;
                c &= 0177;
                if (c == '\n' || c == '\r')
                        break;
                if (c == 'B')
                        len = 0;        /* in case of leading garbage */
                baud[len] = c;
        }
        baud[len] = '\0';
        for (ps = portspeeds; ps->ps_baud; ps++)
                if (strcmp(ps->ps_baud, baud) == 0) {
                        type = ps->ps_type;
                        break;
                }
        sleep(2);       /* wait for connection to complete */
        return (type);
}

/*
 * This auto-baud speed select mechanism is written for the Micom 600
 * portselector. Selection is done by looking at how the character '\r'
 * is garbled at the different speeds.
 */
const char *
autobaud(void)
{
        struct pollfd set[1];
        struct timespec timeout;
        char c;
        const char *type = "9600-baud";

        (void)tcflush(0, TCIOFLUSH);
        set[0].fd = STDIN_FILENO;
        set[0].events = POLLIN;
        if (poll(set, 1, 5000) <= 0)
                return (type);
        if (read(STDIN_FILENO, &c, sizeof(char)) != sizeof(char))
                return (type);
        timeout.tv_sec = 0;
        timeout.tv_nsec = 20000;
        (void)nanosleep(&timeout, NULL);
        (void)tcflush(0, TCIOFLUSH);
        switch (c & 0377) {

        case 0200:              /* 300-baud */
                type = "300-baud";
                break;

        case 0346:              /* 1200-baud */
                type = "1200-baud";
                break;

        case  015:              /* 2400-baud */
        case 0215:
                type = "2400-baud";
                break;

        default:                /* 4800-baud */
                type = "4800-baud";
                break;

        case 0377:              /* 9600-baud */
                type = "9600-baud";
                break;
        }
        return (type);
}