/*      $NetBSD: tty.c,v 1.10 2021/07/24 21:31:31 andvar Exp $  */

#include <sys/cdefs.h>

#ifndef lint
__RCSID("$NetBSD: tty.c,v 1.10 2021/07/24 21:31:31 andvar Exp $");
#endif

#include <sys/stat.h>

#include "sh.h"
#define EXTERN
#include "tty.h"
#undef EXTERN

int
get_tty(fd, ts)
        int fd;
        TTY_state *ts;
{
        int ret;

# ifdef HAVE_TERMIOS_H
        ret = tcgetattr(fd, ts);
# else /* HAVE_TERIOS_H */
#  ifdef HAVE_TERMIO_H
        ret = ioctl(fd, TCGETA, ts);
#  else /* HAVE_TERMIO_H */
        ret = ioctl(fd, TIOCGETP, &ts->sgttyb);
#   ifdef TIOCGATC
        if (ioctl(fd, TIOCGATC, &ts->lchars) < 0)
                ret = -1;
#   else
        if (ioctl(fd, TIOCGETC, &ts->tchars) < 0)
                ret = -1;
#    ifdef TIOCGLTC
        if (ioctl(fd, TIOCGLTC, &ts->ltchars) < 0)
                ret = -1;
#    endif /* TIOCGLTC */
#   endif /* TIOCGATC */
#  endif /* HAVE_TERMIO_H */
# endif /* HAVE_TERIOS_H */
        return ret;
}

int
set_tty(fd, ts, flags)
        int fd;
        TTY_state *ts;
        int flags;
{
        int ret = 0;

# ifdef HAVE_TERMIOS_H
        ret = tcsetattr(fd, TCSADRAIN, ts);
# else /* HAVE_TERIOS_H */
#  ifdef HAVE_TERMIO_H
#   ifndef TCSETAW                              /* e.g. Cray-2 */
                /* first wait for output to drain */
#    ifdef TCSBRK
                if (ioctl(tty_fd, TCSBRK, 1) < 0)
                        ret = -1;
#    else /* the following kludge is minimally intrusive, but sometimes fails */
                if (flags & TF_WAIT)
                        sleep((unsigned)1);     /* fake it */
#    endif
#   endif /* !TCSETAW */
#   if defined(_BSD_SYSV) || !defined(TCSETAW)
/* _BSD_SYSV must force TIOCSETN instead of TIOCSETP (preserve type-ahead) */
                if (ioctl(tty_fd, TCSETA, ts) < 0)
                        ret = -1;
#   else
                if (ioctl(tty_fd, TCSETAW, ts) < 0)
                        ret = -1;
#   endif
#  else /* HAVE_TERMIO_H */
            ret = ioctl(fd, TIOCSETN, &ts->sgttyb);
#   ifdef TIOCGATC
        if (ioctl(fd, TIOCSATC, &ts->lchars) < 0)
                ret = -1;
#   else
        if (ioctl(fd, TIOCSETC, &ts->tchars) < 0)
                ret = -1;
#    ifdef TIOCGLTC
        if (ioctl(fd, TIOCSLTC, &ts->ltchars) < 0)
                ret = -1;
#    endif /* TIOCGLTC */
#   endif /* TIOCGATC */
#  endif /* HAVE_TERMIO_H */
# endif /* HAVE_TERIOS_H */
        return ret;
}


/* Initialize tty_fd.  Used for saving/resetting tty modes upon
 * foreground job completion and for setting up tty process group.
 */
void
tty_init(init_ttystate)
        int init_ttystate;
{
        int     do_close = 1;
        int     tfd;
        const char      *devtty = _PATH_TTY;

        if (tty_fd >= 0) {
                close(tty_fd);
                tty_fd = -1;
        }
        tty_devtty = 1;

        if ((tfd = open(devtty, O_RDWR, 0)) < 0) {
                if (tfd < 0) {
                        tty_devtty = 0;
                        warningf(false,
                                "No controlling tty (open %s: %s)",
                                devtty, strerror(errno));
                }
        }

        if (tfd < 0) {
                do_close = 0;
                if (isatty(0))
                        tfd = 0;
                else if (isatty(2))
                        tfd = 2;
                else {
                        warningf(false, "Can't find tty file descriptor");
                        return;
                }
        }
        if ((tty_fd = ksh_dupbase(tfd, FDBASE)) < 0) {
                warningf(false, "j_ttyinit: dup of tty fd failed: %s",
                        strerror(errno));
        } else if (fd_clexec(tty_fd) < 0) {
                warningf(false, "j_ttyinit: can't set close-on-exec flag: %s",
                        strerror(errno));
                close(tty_fd);
                tty_fd = -1;
        } else if (init_ttystate)
                get_tty(tty_fd, &tty_state);
        if (do_close)
                close(tfd);
}

void
tty_close()
{
        if (tty_fd >= 0) {
                close(tty_fd);
                tty_fd = -1;
        }
}