xref: /netbsd-src/games/backgammon/common_source/one.c (revision de1dfb1250df962f1ff3a011772cf58e605aed11)
1 /*	$NetBSD: one.c,v 1.5 2003/08/07 09:36:57 agc 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 1.5 2003/08/07 09:36:57 agc Exp $");
38 #endif
39 #endif /* not lint */
40 
41 #include "back.h"
42 
43 int
44 makmove(i)
45 	int     i;
46 {
47 	int     n, d;
48 	int     max;
49 
50 	d = d0;
51 	n = abs(g[i] - p[i]);
52 	max = (*offptr < 0 ? 7 : last());
53 	if (board[p[i]] * cturn <= 0)
54 		return (checkd(d) + 2);
55 	if (g[i] != home && board[g[i]] * cturn < -1)
56 		return (checkd(d) + 3);
57 	if (i || D0 == D1) {
58 		if (n == max ? D1 < n : D1 != n)
59 			return (checkd(d) + 1);
60 	} else {
61 		if (n == max ? D0 < n && D1 < n : D0 != n && D1 != n)
62 			return (checkd(d) + 1);
63 		if (n == max ? D0 < n : D0 != n) {
64 			if (d0)
65 				return (checkd(d) + 1);
66 			swap;
67 		}
68 	}
69 	if (g[i] == home && *offptr < 0)
70 		return (checkd(d) + 4);
71 	h[i] = 0;
72 	board[p[i]] -= cturn;
73 	if (g[i] != home) {
74 		if (board[g[i]] == -cturn) {
75 			board[home] -= cturn;
76 			board[g[i]] = 0;
77 			h[i] = 1;
78 			if (abs(bar - g[i]) < 7) {
79 				(*inopp)--;
80 				if (*offopp >= 0)
81 					*offopp -= 15;
82 			}
83 		}
84 		board[g[i]] += cturn;
85 		if (abs(home - g[i]) < 7 && abs(home - p[i]) > 6) {
86 			(*inptr)++;
87 			if (*inptr + *offptr == 0)
88 				*offptr += 15;
89 		}
90 	} else {
91 		(*offptr)++;
92 		(*inptr)--;
93 	}
94 	return (0);
95 }
96 
97 void
98 moverr(i)
99 	int     i;
100 {
101 	int     j;
102 
103 	if (tflag)
104 		curmove(20, 0);
105 	else
106 		writec('\n');
107 	writel("Error:  ");
108 	for (j = 0; j <= i; j++) {
109 		wrint(p[j]);
110 		writec('-');
111 		wrint(g[j]);
112 		if (j < i)
113 			writec(',');
114 	}
115 	writel("... ");
116 	movback(i);
117 }
118 
119 
120 int
121 checkd(d)
122 	int     d;
123 {
124 	if (d0 != d)
125 		swap;
126 	return (0);
127 }
128 
129 int
130 last()
131 {
132 	int     i;
133 
134 	for (i = home - 6 * cturn; i != home; i += cturn)
135 		if (board[i] * cturn > 0)
136 			return (abs(home - i));
137 	return (-1);
138 }
139 
140 void
141 movback(i)
142 	int     i;
143 {
144 	int     j;
145 
146 	for (j = i - 1; j >= 0; j--)
147 		backone(j);
148 }
149 
150 void
151 backone(i)
152 	int     i;
153 {
154 	board[p[i]] += cturn;
155 	if (g[i] != home) {
156 		board[g[i]] -= cturn;
157 		if (abs(g[i] - home) < 7 && abs(p[i] - home) > 6) {
158 			(*inptr)--;
159 			if (*inptr + *offptr < 15 && *offptr >= 0)
160 				*offptr -= 15;
161 		}
162 	} else {
163 		(*offptr)--;
164 		(*inptr)++;
165 	}
166 	if (h[i]) {
167 		board[home] += cturn;
168 		board[g[i]] = -cturn;
169 		if (abs(bar - g[i]) < 7) {
170 			(*inopp)++;
171 			if (*inopp + *offopp == 0)
172 				*offopp += 15;
173 		}
174 	}
175 }
176