games/backgammon/common_source/one.c

   1 /*-
   2  * Copyright (c) 1980, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * @(#)one.c    8.1 (Berkeley) 5/31/93
  30  * $FreeBSD: src/games/backgammon/common_source/one.c,v 1.5 1999/11/30 03:48:27 billf Exp $
  31  * $DragonFly: src/games/backgammon/common_source/one.c,v 1.3 2006/08/08 16:36:11 pavalos Exp $
  32  */
  33
  34 #include "back.h"
  35
  36 static int      checkd(int);
  37 static int      last(void);
  38
  39 int
  40 makmove(int i)
  41 {
  42         int n, d;
  43         int max;
  44
  45         d = d0;
  46         n = abs(g[i] - p[i]);
  47         max = (*offptr < 0 ? 7 : last());
  48         if (board[p[i]] * cturn <= 0)
  49                 return (checkd(d) + 2);
  50         if (g[i] != home && board[g[i]] * cturn < -1)
  51                 return (checkd(d) + 3);
  52         if (i || D0 == D1) {
  53                 if (n == max ? D1 < n : D1 != n)
  54                         return (checkd(d) + 1);
  55         } else {
  56                 if (n == max ? D0 < n && D1 < n : D0 != n && D1 != n)
  57                         return (checkd(d) + 1);
  58                 if (n == max ? D0 < n : D0 != n) {
  59                         if (d0)
  60                                 return (checkd(d) + 1);
  61                         swap;
  62                 }
  63         }
  64         if (g[i] == home && *offptr < 0)
  65                 return (checkd(d) + 4);
  66         h[i] = 0;
  67         board[p[i]] -= cturn;
  68         if (g[i] != home) {
  69                 if (board[g[i]] == -cturn) {
  70                         board[home] -= cturn;
  71                         board[g[i]] = 0;
  72                         h[i] = 1;
  73                         if (abs(bar - g[i]) < 7) {
  74                                 (*inopp)--;
  75                                 if (*offopp >= 0)
  76                                         *offopp -= 15;
  77                         }
  78                 }
  79                 board[g[i]] += cturn;
  80                 if (abs(home - g[i]) < 7 && abs(home - p[i]) > 6) {
  81                         (*inptr)++;
  82                         if (*inptr + *offptr == 0)
  83                                 *offptr += 15;
  84                 }
  85         } else {
  86                 (*offptr)++;
  87                 (*inptr)--;
  88         }
  89         return (0);
  90 }
  91
  92 void
  93 moverr(int i)
  94 {
  95         int j;
  96
  97         if (tflag)
  98                 curmove(20, 0);
  99         else
 100                 writec('\n');
 101         writel("Error:  ");
 102         for (j = 0; j <= i; j++) {
 103                 wrint(p[j]);
 104                 writec('-');
 105                 wrint(g[j]);
 106                 if (j < i)
 107                         writec(',');
 108         }
 109         writel("... ");
 110         movback(i);
 111 }
 112
 113 static int
 114 checkd(int d)
 115 {
 116         if (d0 != d)
 117                 swap;
 118         return (0);
 119 }
 120
 121 static int
 122 last(void)
 123 {
 124         int i;
 125
 126         for (i = home - 6 * cturn; i != home; i += cturn)
 127                 if (board[i] * cturn > 0)
 128                         return (abs(home - i));
 129         return (-1);
 130 }
 131
 132 void
 133 movback(int i)
 134 {
 135         int j;
 136
 137         for (j = i - 1; j >= 0; j--)
 138                 backone(j);
 139 }
 140
 141 void
 142 backone(int i)
 143 {
 144         board[p[i]] += cturn;
 145         if (g[i] != home) {
 146                 board[g[i]] -= cturn;
 147                 if (abs(g[i] - home) < 7 && abs(p[i] - home) > 6) {
 148                         (*inptr)--;
 149                         if (*inptr + *offptr < 15 && *offptr >= 0)
 150                                 *offptr -= 15;
 151                 }
 152         } else {
 153                 (*offptr)--;
 154                 (*inptr)++;
 155         }
 156         if (h[i]) {
 157                 board[home] += cturn;
 158                 board[g[i]] = -cturn;
 159                 if (abs(bar - g[i]) < 7) {
 160                         (*inopp)++;
 161                         if (*inopp + *offopp == 0)
 162                                 *offopp += 15;
 163                 }
 164         }
 165 }