Colony » Colony Scout

/*-

 * Copyright (c) 1992, 1993

 *        The Regents of the University of California.  All rights reserved.

 *

 * This code is derived from software contributed to Berkeley by

 * Chris Torek and Darren F. Provine.

 *

 * 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.

 *

 *        @(#)input.c        8.1 (Berkeley) 5/31/93

 */

/* Modified for Prex by Kohsuke Ohtani. */

/*

 * Tetris input.

 */

#include <sys/types.h>

#include <sys/time.h>

#include <sys/termios.h>

#include <sys/prex.h>

#include <errno.h>

#include <unistd.h>

#include "input.h"

#include "tetris.h"

/* return true if the given timeval is positive */

#define        TV_POS(tv) \

        ((tv)->tv_sec > 0 || ((tv)->tv_sec == 0 && (tv)->tv_usec > 0))

/* subtract timeval `sub' from `res' */

#define        TV_SUB(res, sub) \

        (res)->tv_sec -= (sub)->tv_sec; \

        (res)->tv_usec -= (sub)->tv_usec; \

        if ((res)->tv_usec < 0) { \

                (res)->tv_usec += 1000000; \

                (res)->tv_sec--; \

        }

/*

 * Do a `read wait': select for reading from stdin, with timeout *tvp.

 * On return, modify *tvp to reflect the amount of time spent waiting.

 * It will be positive only if input appeared before the time ran out;

 * otherwise it will be zero or perhaps negative.

 *

 * If tvp is nil, wait forever, but return if select is interrupted.

 *

 * Return 0 => no input, 1 => can read() from stdin

 */

int

rwait(struct timeval *tvp)

{

        int i, ninq, timeout;

        struct timeval starttv, endtv;

#define        NILTZ ((struct timezone *)0)

        if (tvp) {

                (void) gettimeofday(&starttv, NILTZ);

                endtv = *tvp;

                timeout = tvp->tv_usec / 1000;

        } else

                timeout = 1000;

        /*

         * We don't have select() or poll() as for now.

         * This is replaced by polling TTY input queue via ioctl().

         */

        for (i = 0; i < timeout; i++) {

                ioctl(1, TIOCINQ, &ninq);

                if (ninq > 0)

                        break;

                timer_sleep(1, 0);        /* wait 1ms */

        }

        if (i >= timeout) {        /* timed out */

                if (tvp == NULL)

                        return (-1);

                else {

                        tvp->tv_sec = 0;

                        tvp->tv_usec = 0;

                        return (0);

                }

        }

        if (tvp) {

                /* since there is input, we may not have timed out */

                (void) gettimeofday(&endtv, NILTZ);

                TV_SUB(&endtv, &starttv);

                TV_SUB(tvp, &endtv);        /* adjust *tvp by elapsed time */

        }

        return (1);

}

/*

 * `sleep' for the current turn time (using select).

 * Eat any input that might be available.

 */

void

tsleep(void)

{

        struct timeval tv;

        char c;

        tv.tv_sec = 0;

        tv.tv_usec = fallrate;

        while (TV_POS(&tv))

                if (rwait(&tv) && read(0, &c, 1) != 1)

                        break;

}

/*

 * Eat up any input (used at end of game).

 */

void

eat_input(void)

{

        struct timeval tv;

        char c;

        do {

                tv.tv_sec = tv.tv_usec = 0;

        } while (rwait(&tv) && read(0, &c, 1) == 1);

}

/*

 * getchar with timeout.

 */

int

tgetchar(void)

{

        static struct timeval timeleft;

        char c;

        /*

         * Reset timeleft to fallrate whenever it is not positive.

         * In any case, wait to see if there is any input.  If so,

         * take it, and update timeleft so that the next call to

         * tgetchar() will not wait as long.  If there is no input,

         * make timeleft zero or negative, and return -1.

         *

         * Most of the hard work is done by rwait().

         */

        if (!TV_POS(&timeleft)) {

                faster();        /* go faster */

                timeleft.tv_sec = 0;

                timeleft.tv_usec = fallrate;

        }

        if (!rwait(&timeleft))

                return (-1);

        if (read(0, &c, 1) != 1)

                stop("end of file, help");

        return ((int)(unsigned char)c);

}