/* $XTermId: resize.c,v 1.144 2020/06/03 00:26:23 tom Exp $ */

/*
 * Copyright 2003-2018,2020 by Thomas E. Dickey
 *
 *                         All Rights Reserved
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE ABOVE LISTED COPYRIGHT HOLDER(S) BE LIABLE FOR ANY
 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 * Except as contained in this notice, the name(s) of the above copyright
 * holders shall not be used in advertising or otherwise to promote the
 * sale, use or other dealings in this Software without prior written
 * authorization.
 *
 *
 * Copyright 1987 by Digital Equipment Corporation, Maynard, Massachusetts.
 *
 *                         All Rights Reserved
 *
 * Permission to use, copy, modify, and distribute this software and its
 * documentation for any purpose and without fee is hereby granted,
 * provided that the above copyright notice appear in all copies and that
 * both that copyright notice and this permission notice appear in
 * supporting documentation, and that the name of Digital Equipment
 * Corporation not be used in advertising or publicity pertaining to
 * distribution of the software without specific, written prior permission.
 *
 *
 * DIGITAL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
 * ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
 * DIGITAL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
 * ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
 * WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
 * ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 * SOFTWARE.
 */

/* resize.c */

#include <stdio.h>
#include <ctype.h>

#ifdef RESIZE_ONLY
#include "resize.h"
#else
#include <xterm.h>
#include <version.h>
#include <xstrings.h>
#include <xtermcap.h>
#include <xterm_io.h>
#endif

#ifndef USE_TERMINFO            /* avoid conflict with configure script */
#if defined(__QNX__) || defined(__SCO__) || defined(linux) || defined(__OpenBSD__) || defined(__UNIXWARE__)
#define USE_TERMINFO
#endif
#endif

#if defined(__QNX__)
#include <unix.h>
#endif

/*
 * Some OS's may want to use both, like SCO for example.  We catch here anyone
 * who hasn't decided what they want.
 */
#if !defined(USE_TERMCAP) && !defined(USE_TERMINFO)
#define USE_TERMINFO
#endif

#include <signal.h>
#include <pwd.h>

#ifdef USE_IGNORE_RC
int ignore_unused;
#endif

#ifdef __MVS__
#define ESCAPE(string) "\047" string
#else
#define ESCAPE(string) "\033" string
#endif

#define EMULATIONS      2
#define SUN             1
#define VT100           0

#define TIMEOUT         10

#define SHELL_UNKNOWN   0
#define SHELL_C         1
#define SHELL_BOURNE    2

/* *INDENT-OFF* */
static struct {
    const char *name;
    int type;
} shell_list[] = {
    { "csh",    SHELL_C },      /* vanilla cshell */
    { "jcsh",   SHELL_C },
    { "tcsh",   SHELL_C },
    { "sh",     SHELL_BOURNE }, /* vanilla Bourne shell */
    { "ash",    SHELL_BOURNE },
    { "bash",   SHELL_BOURNE }, /* GNU Bourne again shell */
    { "dash",   SHELL_BOURNE },
    { "jsh",    SHELL_BOURNE },
    { "ksh",    SHELL_BOURNE }, /* Korn shell (from AT&T toolchest) */
    { "ksh-i",  SHELL_BOURNE }, /* another name for Korn shell */
    { "ksh93",  SHELL_BOURNE }, /* Korn shell */
    { "mksh",   SHELL_BOURNE },
    { "pdksh",  SHELL_BOURNE },
    { "zsh",    SHELL_BOURNE },
    { NULL,     SHELL_BOURNE }  /* default (same as xterm's) */
};
/* *INDENT-ON* */

static const char *const emuname[EMULATIONS] =
{
    "VT100",
    "Sun",
};
static char *myname;
static int shell_type = SHELL_UNKNOWN;
static const char *const getsize[EMULATIONS] =
{
    ESCAPE("7") ESCAPE("[r") ESCAPE("[9999;9999H") ESCAPE("[6n"),
    ESCAPE("[18t"),
};
#if defined(USE_STRUCT_WINSIZE)
static const char *const getwsize[EMULATIONS] =
{                               /* size in pixels */
    0,
    ESCAPE("[14t"),
};
#endif /* USE_STRUCT_WINSIZE */
static const char *const restore[EMULATIONS] =
{
    ESCAPE("8"),
    0,
};
static const char *const setsize[EMULATIONS] =
{
    0,
    ESCAPE("[8;%s;%st"),
};

#ifdef USE_ANY_SYSV_TERMIO
static struct termio tioorig;
#elif defined(USE_TERMIOS)
static struct termios tioorig;
#else
static struct sgttyb sgorig;
#endif /* USE_ANY_SYSV_TERMIO/USE_TERMIOS */

static const char *const size[EMULATIONS] =
{
    ESCAPE("[%d;%dR"),
    ESCAPE("[8;%d;%dt"),
};
static const char sunname[] = "sunsize";
static int tty;
static FILE *ttyfp;

#if defined(USE_STRUCT_WINSIZE)
static const char *wsize[EMULATIONS] =
{
    0,
    ESCAPE("[4;%hd;%hdt"),
};
#endif /* USE_STRUCT_WINSIZE */

static void failed(const char *) GCC_NORETURN;
static void onintr(int) GCC_NORETURN;
static void resize_timeout(int) GCC_NORETURN;
static void Usage(void) GCC_NORETURN;

static void
failed(const char *s)
{
    int save = errno;
    IGNORE_RC(write(2, myname, strlen(myname)));
    IGNORE_RC(write(2, ": ", (size_t) 2));
    errno = save;
    perror(s);
    exit(EXIT_FAILURE);
}

/* ARGSUSED */
static void
onintr(int sig GCC_UNUSED)
{
#ifdef USE_ANY_SYSV_TERMIO
    (void) ioctl(tty, TCSETAW, &tioorig);
#elif defined(USE_TERMIOS)
    (void) tcsetattr(tty, TCSADRAIN, &tioorig);
#else /* not USE_TERMIOS */
    (void) ioctl(tty, TIOCSETP, &sgorig);
#endif /* USE_ANY_SYSV_TERMIO/USE_TERMIOS */
    exit(EXIT_FAILURE);
}

static void
resize_timeout(int sig)
{
    fprintf(stderr, "\n%s: Time out occurred\r\n", myname);
    onintr(sig);
}

static void
Usage(void)
{
    fprintf(stderr, strcmp(myname, sunname) == 0 ?
            "Usage: %s [rows cols]\n" :
            "Usage: %s [-v] [-u] [-c] [-s [rows cols]]\n", myname);
    exit(EXIT_FAILURE);
}

#ifdef USE_TERMCAP
static void
print_termcap(const char *termcap)
{
    int ch;

    putchar('\'');
    while ((ch = *termcap++) != '\0') {
        switch (ch & 0xff) {
        case 127:               /* undo bug in GNU termcap */
            printf("^?");
            break;
        case '\'':              /* must escape anyway (unlikely) */
            /* FALLTHRU */
        case '!':               /* must escape for SunOS csh */
            putchar('\\');
            /* FALLTHRU */
        default:
            putchar(ch);
            break;
        }
    }
    putchar('\'');
}
#endif /* USE_TERMCAP */

static int
checkdigits(char *str)
{
    while (*str) {
        if (!isdigit(CharOf(*str)))
            return (0);
        str++;
    }
    return (1);
}

static void
readstring(FILE *fp, char *buf, const char *str)
{
    int last, c;
#if !defined(USG) && !defined(__minix)
    /* What is the advantage of setitimer() over alarm()? */
    struct itimerval it;
#endif

    signal(SIGALRM, resize_timeout);
#if defined(USG) || defined(__minix)
    alarm(TIMEOUT);
#else
    memset((char *) &it, 0, sizeof(struct itimerval));
    it.it_value.tv_sec = TIMEOUT;
    setitimer(ITIMER_REAL, &it, (struct itimerval *) NULL);
#endif
    if ((c = getc(fp)) == 0233) {       /* meta-escape, CSI */
        c = ESCAPE("")[0];
        *buf++ = (char) c;
        *buf++ = '[';
    } else {
        *buf++ = (char) c;
    }
    if (c != *str) {
        fprintf(stderr, "%s: unknown character, exiting.\r\n", myname);
        onintr(0);
    }
    last = str[strlen(str) - 1];
    while ((*buf++ = (char) getc(fp)) != last) {
        ;
    }
#if defined(USG) || defined(__minix)
    alarm(0);
#else
    memset((char *) &it, 0, sizeof(struct itimerval));
    setitimer(ITIMER_REAL, &it, (struct itimerval *) NULL);
#endif
    *buf = 0;
}

/*
   resets termcap string to reflect current screen size
 */
int
main(int argc, char **argv ENVP_ARG)
{
#ifdef USE_TERMCAP
    char *env;
#endif
    char *ptr;
    int emu = VT100;
    char *shell;
    int i;
    int rc;
    int rows, cols;
#ifdef USE_ANY_SYSV_TERMIO
    struct termio tio;
#elif defined(USE_TERMIOS)
    struct termios tio;
#else
    struct sgttyb sg;
#endif /* USE_ANY_SYSV_TERMIO/USE_TERMIOS */
#ifdef USE_TERMCAP
    int ok_tcap = 1;
    char termcap[TERMCAP_SIZE];
    char newtc[TERMCAP_SIZE];
#endif /* USE_TERMCAP */
    char buf[BUFSIZ];
#ifdef TTYSIZE_STRUCT
    TTYSIZE_STRUCT ts;
#endif
    char *name_of_tty;
#ifdef CANT_OPEN_DEV_TTY
    extern char *ttyname();
#endif
    const char *setname = "";

    myname = x_basename(argv[0]);
    if (strcmp(myname, sunname) == 0)
        emu = SUN;
    for (argv++, argc--; argc > 0 && **argv == '-'; argv++, argc--) {
        switch ((*argv)[1]) {
        case 's':               /* Sun emulation */
            if (emu == SUN)
                Usage();        /* Never returns */
            emu = SUN;
            break;
        case 'u':               /* Bourne (Unix) shell */
            shell_type = SHELL_BOURNE;
            break;
        case 'c':               /* C shell */
            shell_type = SHELL_C;
            break;
        case 'v':
            printf("%s\n", xtermVersion());
            exit(EXIT_SUCCESS);
        default:
            Usage();            /* Never returns */
        }
    }

    if (SHELL_UNKNOWN == shell_type) {
        /* Find out what kind of shell this user is running.
         * This is the same algorithm that xterm uses.
         */
        if ((ptr = x_getenv("SHELL")) == NULL) {
            uid_t uid = getuid();
            struct passwd pw;

            if (x_getpwuid(uid, &pw)) {
                (void) x_getlogin(uid, &pw);
            }
            if (!OkPasswd(&pw)
                || *(ptr = pw.pw_shell) == 0) {
                /* this is the same default that xterm uses */
                ptr = x_strdup("/bin/sh");
            }
        }

        shell = x_basename(ptr);

        /* now that we know, what kind is it? */
        for (i = 0; shell_list[i].name; i++) {
            if (!strcmp(shell_list[i].name, shell)) {
                break;
            }
        }
        shell_type = shell_list[i].type;
    }

    if (argc == 2) {
        if (!setsize[emu]) {
            fprintf(stderr,
                    "%s: Can't set window size under %s emulation\n",
                    myname, emuname[emu]);
            exit(EXIT_FAILURE);
        }
        if (!checkdigits(argv[0]) || !checkdigits(argv[1])) {
            Usage();            /* Never returns */
        }
    } else if (argc != 0) {
        Usage();                /* Never returns */
    }
#ifdef CANT_OPEN_DEV_TTY
    if ((name_of_tty = ttyname(fileno(stderr))) == NULL)
#endif
        name_of_tty = x_strdup("/dev/tty");

    if ((ttyfp = fopen(name_of_tty, "r+")) == NULL) {
        fprintf(stderr, "%s:  can't open terminal %s\n",
                myname, name_of_tty);
        exit(EXIT_FAILURE);
    }
    tty = fileno(ttyfp);
#ifdef USE_TERMCAP
    if ((env = x_getenv("TERM")) == 0) {
        env = x_strdup(DFT_TERMTYPE);
        if (SHELL_BOURNE == shell_type) {
            setname = "TERM=" DFT_TERMTYPE ";\nexport TERM;\n";
        } else {
            setname = "setenv TERM " DFT_TERMTYPE ";\n";
        }
    }
    termcap[0] = 0;             /* ...just in case we've accidentally gotten terminfo */
    if (tgetent(termcap, env) <= 0 || termcap[0] == 0) {
        ok_tcap = 0;
    }
#endif /* USE_TERMCAP */
#ifdef USE_TERMINFO
    if (x_getenv("TERM") == 0) {
        if (SHELL_BOURNE == shell_type) {
            setname = "TERM=" DFT_TERMTYPE ";\nexport TERM;\n";
        } else {
            setname = "setenv TERM " DFT_TERMTYPE ";\n";
        }
    }
#endif /* USE_TERMINFO */

#ifdef USE_ANY_SYSV_TERMIO
    rc = ioctl(tty, TCGETA, &tioorig);
    tio = tioorig;
    UIntClr(tio.c_iflag, (ICRNL | IUCLC));
    UIntClr(tio.c_lflag, (ICANON | ECHO));
    tio.c_cflag |= CS8;
    tio.c_cc[VMIN] = 6;
    tio.c_cc[VTIME] = 1;
#elif defined(USE_TERMIOS)
    rc = tcgetattr(tty, &tioorig);
    tio = tioorig;
    UIntClr(tio.c_iflag, ICRNL);
    UIntClr(tio.c_lflag, (ICANON | ECHO));
    tio.c_cflag |= CS8;
    tio.c_cc[VMIN] = 6;
    tio.c_cc[VTIME] = 1;
#else /* not USE_TERMIOS */
    rc = ioctl(tty, TIOCGETP, &sgorig);
    sg = sgorig;
    sg.sg_flags |= RAW;
    UIntClr(sg.sg_flags, ECHO);
#endif /* USE_ANY_SYSV_TERMIO/USE_TERMIOS */
    if (rc != 0)
        failed("get tty settings");

    signal(SIGINT, onintr);
    signal(SIGQUIT, onintr);
    signal(SIGTERM, onintr);

#ifdef USE_ANY_SYSV_TERMIO
    rc = ioctl(tty, TCSETAW, &tio);
#elif defined(USE_TERMIOS)
    rc = tcsetattr(tty, TCSADRAIN, &tio);
#else /* not USE_TERMIOS */
    rc = ioctl(tty, TIOCSETP, &sg);
#endif /* USE_ANY_SYSV_TERMIO/USE_TERMIOS */
    if (rc != 0)
        failed("set tty settings");

    if (argc == 2) {            /* look for optional parameters of "-s" */
        char *tmpbuf = TypeMallocN(char,
                                   strlen(setsize[emu]) +
                                   strlen(argv[0]) +
                                   strlen(argv[1]) +
                                   1);
        if (tmpbuf == 0) {
            fprintf(stderr, "%s: Cannot query size\n", myname);
            onintr(0);
        } else {
            sprintf(tmpbuf, setsize[emu], argv[0], argv[1]);
            IGNORE_RC(write(tty, tmpbuf, strlen(tmpbuf)));
            free(tmpbuf);
        }
    }
    IGNORE_RC(write(tty, getsize[emu], strlen(getsize[emu])));
    readstring(ttyfp, buf, size[emu]);
    if (sscanf(buf, size[emu], &rows, &cols) != 2) {
        fprintf(stderr, "%s: Can't get rows and columns\r\n", myname);
        onintr(0);
    }
    if (restore[emu])
        IGNORE_RC(write(tty, restore[emu], strlen(restore[emu])));
#if defined(USE_STRUCT_WINSIZE)
    /* finally, set the tty's window size */
    if (getwsize[emu]) {
        /* get the window size in pixels */
        IGNORE_RC(write(tty, getwsize[emu], strlen(getwsize[emu])));
        readstring(ttyfp, buf, wsize[emu]);
        if (sscanf(buf, wsize[emu], &ts.ws_xpixel, &ts.ws_ypixel) != 2) {
            fprintf(stderr, "%s: Can't get window size\r\n", myname);
            onintr(0);
        }
        setup_winsize(ts, rows, cols, 0, 0);
        SET_TTYSIZE(tty, ts);
    } else if (ioctl(tty, TIOCGWINSZ, &ts) != -1) {
        /* we don't have any way of directly finding out
           the current height & width of the window in pixels.  We try
           our best by computing the font height and width from the "old"
           window-size values, and multiplying by these ratios... */
#define scaled(old,new,len) (old)?((unsigned)(new)*(len)/(old)):(len)
        setup_winsize(ts, rows, cols,
                      scaled(TTYSIZE_ROWS(ts), rows, ts.ws_ypixel),
                      scaled(TTYSIZE_COLS(ts), cols, ts.ws_xpixel));
        SET_TTYSIZE(tty, ts);
    }
#endif /* USE_STRUCT_WINSIZE */

#ifdef USE_ANY_SYSV_TERMIO
    rc = ioctl(tty, TCSETAW, &tioorig);
#elif defined(USE_TERMIOS)
    rc = tcsetattr(tty, TCSADRAIN, &tioorig);
#else /* not USE_TERMIOS */
    rc = ioctl(tty, TIOCSETP, &sgorig);
#endif /* USE_ANY_SYSV_TERMIO/USE_TERMIOS */
    if (rc != 0)
        failed("set tty settings");

    signal(SIGINT, SIG_DFL);
    signal(SIGQUIT, SIG_DFL);
    signal(SIGTERM, SIG_DFL);

#ifdef USE_TERMCAP
    if (ok_tcap) {
        /* update termcap string */
        /* first do columns */
        if ((ptr = x_strindex(termcap, "co#")) == NULL) {
            fprintf(stderr, "%s: No `co#'\n", myname);
            exit(EXIT_FAILURE);
        }

        i = (int) (ptr - termcap) + 3;
        strncpy(newtc, termcap, (size_t) i);
        sprintf(newtc + i, "%d", cols);
        if ((ptr = strchr(ptr, ':')) != 0)
            strcat(newtc, ptr);

        /* now do lines */
        if ((ptr = x_strindex(newtc, "li#")) == NULL) {
            fprintf(stderr, "%s: No `li#'\n", myname);
            exit(EXIT_FAILURE);
        }

        i = (int) (ptr - newtc) + 3;
        strncpy(termcap, newtc, (size_t) i);
        sprintf(termcap + i, "%d", rows);
        if ((ptr = strchr(ptr, ':')) != 0)
            strcat(termcap, ptr);
    }
#endif /* USE_TERMCAP */

    if (SHELL_BOURNE == shell_type) {

#ifdef USE_TERMCAP
        if (ok_tcap) {
            printf("%sTERMCAP=", setname);
            print_termcap(termcap);
            printf(";\nexport TERMCAP;\n");
        }
#endif /* USE_TERMCAP */
#ifdef USE_TERMINFO
        printf("%sCOLUMNS=%d;\nLINES=%d;\nexport COLUMNS LINES;\n",
               setname, cols, rows);
#endif /* USE_TERMINFO */

    } else {                    /* not Bourne shell */

#ifdef USE_TERMCAP
        if (ok_tcap) {
            printf("set noglob;\n%ssetenv TERMCAP ", setname);
            print_termcap(termcap);
            printf(";\nunset noglob;\n");
        }
#endif /* USE_TERMCAP */
#ifdef USE_TERMINFO
        printf("set noglob;\n%ssetenv COLUMNS '%d';\nsetenv LINES '%d';\nunset noglob;\n",
               setname, cols, rows);
#endif /* USE_TERMINFO */
    }
    exit(EXIT_SUCCESS);
}