NetBSD/games/backgammon/common_source/allow.c

111 lines
3.1 KiB
C

/*
* Copyright (c) 1980 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*/
#ifndef lint
/*static char sccsid[] = "from: @(#)allow.c 5.4 (Berkeley) 6/1/90";*/
static char rcsid[] = "$Id: allow.c,v 1.2 1993/08/01 18:56:46 mycroft Exp $";
#endif /* not lint */
#include "back.h"
movallow () {
register int i, m, iold;
int r;
if (d0)
swap;
m = (D0 == D1? 4: 2);
for (i = 0; i < 4; i++)
p[i] = bar;
i = iold = 0;
while (i < m) {
if (*offptr == 15)
break;
h[i] = 0;
if (board[bar]) {
if (i == 1 || m == 4)
g[i] = bar+cturn*D1;
else
g[i] = bar+cturn*D0;
if (r = makmove(i)) {
if (d0 || m == 4)
break;
swap;
movback (i);
if (i > iold)
iold = i;
for (i = 0; i < 4; i++)
p[i] = bar;
i = 0;
} else
i++;
continue;
}
if ((p[i] += cturn) == home) {
if (i > iold)
iold = i;
if (m == 2 && i) {
movback(i);
p[i--] = bar;
if (p[i] != bar)
continue;
else
break;
}
if (d0 || m == 4)
break;
swap;
movback (i);
for (i = 0; i < 4; i++)
p[i] = bar;
i = 0;
continue;
}
if (i == 1 || m == 4)
g[i] = p[i]+cturn*D1;
else
g[i] = p[i]+cturn*D0;
if (g[i]*cturn > home) {
if (*offptr >= 0)
g[i] = home;
else
continue;
}
if (board[p[i]]*cturn > 0 && (r = makmove(i)) == 0)
i++;
}
movback (i);
return (iold > i? iold: i);
}