backgammon/common_source/one.c

   1 /*      $NetBSD: one.c,v 1.8 2012/10/13 18:44:15 dholland Exp $ */
   2
   3 /*
   4  * Copyright (c) 1980, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32 #include <sys/cdefs.h>
  33 #ifndef lint
  34 #if 0
  35 static char sccsid[] = "@(#)one.c       8.1 (Berkeley) 5/31/93";
  36 #else
  37 __RCSID("$NetBSD: one.c,v 1.8 2012/10/13 18:44:15 dholland Exp $");
  38 #endif
  39 #endif /* not lint */
  40
  41 #include "back.h"
  42
  43 static int checkd(int);
  44 static int last(void);
  45
  46 int
  47 makmove(int i)
  48 {
  49         int     n, d;
  50         int     max;
  51         struct move *mm = &gm;
  52
  53         d = mm->d0;
  54         n = abs(mm->g[i] - mm->p[i]);
  55         max = (*offptr < 0 ? 7 : last());
  56         if (board[mm->p[i]] * cturn <= 0)
  57                 return (checkd(d) + 2);
  58         if (mm->g[i] != home && board[mm->g[i]] * cturn < -1)
  59                 return (checkd(d) + 3);
  60         if (i || mm->D0 == mm->D1) {
  61                 if (n == max ? mm->D1 < n : mm->D1 != n)
  62                         return (checkd(d) + 1);
  63         } else {
  64                 if (n == max ? mm->D0 < n && mm->D1 < n : mm->D0 != n && mm->D1 != n)
  65                         return (checkd(d) + 1);
  66                 if (n == max ? mm->D0 < n : mm->D0 != n) {
  67                         if (mm->d0)
  68                                 return (checkd(d) + 1);
  69                         mswap(mm);
  70                 }
  71         }
  72         if (mm->g[i] == home && *offptr < 0)
  73                 return (checkd(d) + 4);
  74         mm->h[i] = 0;
  75         board[mm->p[i]] -= cturn;
  76         if (mm->g[i] != home) {
  77                 if (board[mm->g[i]] == -cturn) {
  78                         board[home] -= cturn;
  79                         board[mm->g[i]] = 0;
  80                         mm->h[i] = 1;
  81                         if (abs(bar - mm->g[i]) < 7) {
  82                                 (*inopp)--;
  83                                 if (*offopp >= 0)
  84                                         *offopp -= 15;
  85                         }
  86                 }
  87                 board[mm->g[i]] += cturn;
  88                 if (abs(home - mm->g[i]) < 7 && abs(home - mm->p[i]) > 6) {
  89                         (*inptr)++;
  90                         if (*inptr + *offptr == 0)
  91                                 *offptr += 15;
  92                 }
  93         } else {
  94                 (*offptr)++;
  95                 (*inptr)--;
  96         }
  97         return (0);
  98 }
  99
 100 void
 101 moverr(int i)
 102 {
 103         int     j;
 104         struct move *mm = &gm;
 105
 106         if (tflag)
 107                 curmove(20, 0);
 108         else
 109                 writec('\n');
 110         writel("Error:  ");
 111         for (j = 0; j <= i; j++) {
 112                 wrint(mm->p[j]);
 113                 writec('-');
 114                 wrint(mm->g[j]);
 115                 if (j < i)
 116                         writec(',');
 117         }
 118         writel("... ");
 119         movback(i);
 120 }
 121
 122
 123 static int
 124 checkd(int d)
 125 {
 126         struct move *mm = &gm;
 127
 128         if (mm->d0 != d)
 129                 mswap(mm);
 130         return (0);
 131 }
 132
 133 static int
 134 last(void)
 135 {
 136         int     i;
 137
 138         for (i = home - 6 * cturn; i != home; i += cturn)
 139                 if (board[i] * cturn > 0)
 140                         return (abs(home - i));
 141         return (-1);
 142 }
 143
 144 void
 145 movback(int i)
 146 {
 147         int     j;
 148
 149         for (j = i - 1; j >= 0; j--)
 150                 backone(j);
 151 }
 152
 153 void
 154 backone(int i)
 155 {
 156         struct move *mm = &gm;
 157
 158         board[mm->p[i]] += cturn;
 159         if (mm->g[i] != home) {
 160                 board[mm->g[i]] -= cturn;
 161                 if (abs(mm->g[i] - home) < 7 && abs(mm->p[i] - home) > 6) {
 162                         (*inptr)--;
 163                         if (*inptr + *offptr < 15 && *offptr >= 0)
 164                                 *offptr -= 15;
 165                 }
 166         } else {
 167                 (*offptr)--;
 168                 (*inptr)++;
 169         }
 170         if (mm->h[i]) {
 171                 board[home] += cturn;
 172                 board[mm->g[i]] = -cturn;
 173                 if (abs(bar - mm->g[i]) < 7) {
 174                         (*inopp)++;
 175                         if (*inopp + *offopp == 0)
 176                                 *offopp += 15;
 177                 }
 178         }
 179 }