/*      $OpenBSD: terminal.c,v 1.14 2017/07/07 09:14:26 fcambus Exp $   */
/*      $NetBSD: terminal.c,v 1.5 1996/02/28 21:04:17 thorpej Exp $     */

/*
 * Copyright (c) 1988, 1990, 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 "telnet_locl.h"

#include <arpa/telnet.h>
#include <errno.h>
#include <unistd.h>

Ring            ttyoring, ttyiring;
unsigned char   ttyobuf[2*BUFSIZ], ttyibuf[BUFSIZ];

int termdata;                   /* Debugging flag */

/*
 * initialize the terminal data structures.
 */

void
init_terminal(void)
{
        struct termios tc;

        ring_init(&ttyoring, ttyobuf, sizeof ttyobuf);
        ring_init(&ttyiring, ttyibuf, sizeof ttyibuf);

        tcgetattr(0, &tc);
        autoflush = (tc.c_lflag & NOFLSH) == 0;
}

/*
 *              Send as much data as possible to the terminal.
 *
 *              Return value:
 *                      -1: No useful work done, data waiting to go out.
 *                       0: No data was waiting, so nothing was done.
 *                       1: All waiting data was written out.
 *                       n: All data - n was written out.
 */

int
ttyflush(int drop)
{
    int n, n0, n1;

    n0 = ring_full_count(&ttyoring);
    if ((n1 = n = ring_full_consecutive(&ttyoring)) > 0) {
        if (drop) {
            tcflush(fileno(stdout), TCOFLUSH);
            /* we leave 'n' alone! */
        } else {
            n = write(tout, ttyoring.consume, n);
        }
    }
    if (n > 0) {
        if (termdata && n) {
            Dump('>', ttyoring.consume, n);
        }
        /*
         * If we wrote everything, and the full count is
         * larger than what we wrote, then write the
         * rest of the buffer.
         */
        if (n1 == n && n0 > n) {
                n1 = n0 - n;
                if (!drop)
                        n1 = write(tout, ttyoring.bottom, n1);
                if (n1 > 0)
                        n += n1;
        }
        ring_consumed(&ttyoring, n);
    }
    if (n < 0) {
        if (errno == EPIPE)
                kill(0, SIGQUIT);
        return -1;
    }
    if (n == n0) {
        if (n0)
            return -1;
        return 0;
    }
    return n0 - n + 1;
}


/*
 * These routines decides on what the mode should be (based on the values
 * of various global variables).
 */

int
getconnmode(void)
{
    int mode = 0;

    if (my_want_state_is_dont(TELOPT_ECHO))
        mode |= MODE_ECHO;

    if (localflow)
        mode |= MODE_FLOW;

    if ((eight & 1) || my_want_state_is_will(TELOPT_BINARY))
        mode |= MODE_INBIN;

    if (eight & 2)
        mode |= MODE_OUT8;
    if (his_want_state_is_will(TELOPT_BINARY))
        mode |= MODE_OUTBIN;

#ifdef  KLUDGELINEMODE
    if (kludgelinemode) {
        if (my_want_state_is_dont(TELOPT_SGA)) {
            mode |= (MODE_TRAPSIG|MODE_EDIT);
            if (dontlecho && (clocks.echotoggle > clocks.modenegotiated)) {
                mode &= ~MODE_ECHO;
            }
        }
        return(mode);
    }
#endif
    if (my_want_state_is_will(TELOPT_LINEMODE))
        mode |= linemode;
    return(mode);
}

void
setconnmode(int force)
{
    int newmode;

    newmode = getconnmode()|(force?MODE_FORCE:0);

    TerminalNewMode(newmode);
}

void
setcommandmode(void)
{
    TerminalNewMode(-1);
}