usr/src/games/robots/rnd_pos.c

/*
 * Copyright (c) 1980 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that: (1) source distributions retain this entire copyright
 * notice and comment, and (2) distributions including binaries display
 * the following acknowledgement:  ``This product includes software
 * developed by the University of California, Berkeley and its contributors''
 * in the documentation or other materials provided with the distribution
 * and in all advertising materials mentioning features or use of this
 * software. 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 ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

#ifndef lint
static char sccsid[] = "@(#)rnd_pos.c   5.4 (Berkeley) 6/1/90";
#endif /* not lint */

# include       "robots.h"

# define        IS_SAME(p,y,x)  ((p).y != -1 && (p).y == y && (p).x == x)

/*
 * rnd_pos:
 *      Pick a random, unoccupied position
 */
COORD *
rnd_pos()
{
        static COORD    pos;
        static int      call = 0;
        register int    i = 0;

        do {
                pos.y = rnd(Y_FIELDSIZE - 1) + 1;
                pos.x = rnd(X_FIELDSIZE - 1) + 1;
                refresh();
        } while (Field[pos.y][pos.x] != 0);
        call++;
        return &pos;
}

rnd(range)
int     range;
{
        unsigned int    rand();

        return rand() % range;
}