usr/src/games/backgammon/common_source/one.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 this notice is preserved and that due credit is given
 * to the University of California at Berkeley. The name of the University
 * may not be used to endorse or promote products derived from this
 * software without specific prior written permission. This software
 * is provided ``as is'' without express or implied warranty.
 */

#ifndef lint
static char sccsid[] = "@(#)one.c       5.2 (Berkeley) %G%";
#endif /* not lint */

#include "back.h"

makmove (i)
register int    i;

{
        register int    n, d;
        int             max;

        d = d0;
        n = abs(g[i]-p[i]);
        max = (*offptr < 0? 7: last());
        if (board[p[i]]*cturn <= 0)
                return (checkd(d)+2);
        if (g[i] != home && board[g[i]]*cturn < -1)
                return (checkd(d)+3);
        if (i || D0 == D1)  {
                if (n == max? D1 < n: D1 != n)
                        return (checkd(d)+1);
        } else  {
                if (n == max? D0 < n && D1 < n: D0 != n && D1 != n)
                        return (checkd(d)+1);
                if (n == max? D0 < n: D0 != n)  {
                        if (d0)
                                return (checkd(d)+1);
                        swap;
                }
        }
        if (g[i] == home && *offptr < 0)
                return (checkd(d)+4);
        h[i] = 0;
        board[p[i]] -= cturn;
        if (g[i] != home)  {
                if (board[g[i]] == -cturn)  {
                        board[home] -= cturn;
                        board[g[i]] = 0;
                        h[i] = 1;
                        if (abs(bar-g[i]) < 7)  {
                                (*inopp)--;
                                if (*offopp >= 0)
                                        *offopp -= 15;
                        }
                }
                board[g[i]] += cturn;
                if (abs(home-g[i]) < 7 && abs(home-p[i]) > 6)  {
                        (*inptr)++;
                        if (*inptr+*offptr == 0)
                                *offptr += 15;
                }
        } else {
                (*offptr)++;
                (*inptr)--;
        }
        return (0);
}
\f
moverr (i)
register int    i;

{
        register int    j;

        if (tflag)
                curmove (20,0);
        else
                writec ('\n');
        writel ("Error:  ");
        for (j = 0; j <= i; j++)  {
                wrint (p[j]);
                writec ('-');
                wrint (g[j]);
                if (j < i)
                        writec (',');
        }
        writel ("... ");
        movback (i);
}


checkd (d)
register int    d;

{
        if (d0 != d)
                swap;
        return (0);
}

last ()  {
        register int    i;

        for (i = home-6*cturn; i != home; i += cturn)
                if (board[i]*cturn > 0)
                        return (abs(home-i));
}
\f
movback (i)
register int    i;

{
        register int    j;

        for (j = i-1; j >= 0; j--)
                backone(j);
}

backone (i)
register int    i;

{
        board[p[i]] += cturn;
        if (g[i] != home)  {
                board[g[i]] -= cturn;
                if (abs(g[i]-home) < 7 && abs(p[i]-home) > 6)  {
                        (*inptr)--;
                        if (*inptr+*offptr < 15 && *offptr >= 0)
                                *offptr -= 15;
                }
        } else  {
                (*offptr)--;
                (*inptr)++;
        }
        if (h[i])  {
                board[home] += cturn;
                board[g[i]] = -cturn;
                if (abs(bar-g[i]) < 7)  {
                        (*inopp)++;
                        if (*inopp+*offopp == 0)
                                *offopp += 15;
                }
        }
}