xref: /netbsd-src/games/backgammon/common_source/check.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*	$NetBSD: check.c,v 1.8 2012/10/13 19:19:39 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[] = "@(#)check.c	8.1 (Berkeley) 5/31/93";
36 #else
37 __RCSID("$NetBSD: check.c,v 1.8 2012/10/13 19:19:39 dholland Exp $");
38 #endif
39 #endif /* not lint */
40 
41 #include "back.h"
42 
43 void
44 getmove(struct move *mm)
45 {
46 	int     i, c;
47 
48 	c = 0;
49 	for (;;) {
50 		i = checkmove(mm, c);
51 
52 		switch (i) {
53 		case -1:
54 			if (movokay(mm, mm->mvlim)) {
55 				if (tflag)
56 					curmove(20, 0);
57 				else
58 					writec('\n');
59 				for (i = 0; i < mm->mvlim; i++)
60 					if (mm->h[i])
61 						wrhit(mm->g[i]);
62 				nexturn();
63 				if (*offopp == 15)
64 					cturn *= -2;
65 				if (tflag && pnum)
66 					bflag = pnum;
67 				return;
68 			}
69 		case -4:
70 		case 0:
71 			if (tflag)
72 				refresh();
73 			if (i != 0 && i != -4)
74 				break;
75 			if (tflag)
76 				curmove(20, 0);
77 			else
78 				writec('\n');
79 			writel(*Colorptr);
80 			if (i == -4)
81 				writel(" must make ");
82 			else
83 				writel(" can only make ");
84 			writec(mm->mvlim + '0');
85 			writel(" move");
86 			if (mm->mvlim > 1)
87 				writec('s');
88 			writec('.');
89 			writec('\n');
90 			break;
91 
92 		case -3:
93 			if (quit(mm))
94 				return;
95 		}
96 
97 		if (!tflag)
98 			proll(mm);
99 		else {
100 			curmove(cturn == -1 ? 18 : 19, 39);
101 			cline();
102 			c = -1;
103 		}
104 	}
105 }
106 
107 int
108 movokay(struct move *mm, int mv)
109 {
110 	int     i, m;
111 
112 	if (mm->d0)
113 		mswap(mm);
114 
115 	for (i = 0; i < mv; i++) {
116 		if (mm->p[i] == mm->g[i]) {
117 			moverr(mm, i);
118 			curmove(20, 0);
119 			writel("Attempt to move to same location.\n");
120 			return (0);
121 		}
122 		if (cturn * (mm->g[i] - mm->p[i]) < 0) {
123 			moverr(mm, i);
124 			curmove(20, 0);
125 			writel("Backwards move.\n");
126 			return (0);
127 		}
128 		if (abs(board[bar]) && mm->p[i] != bar) {
129 			moverr(mm, i);
130 			curmove(20, 0);
131 			writel("Men still on bar.\n");
132 			return (0);
133 		}
134 		if ((m = makmove(mm, i))) {
135 			moverr(mm, i);
136 			switch (m) {
137 
138 			case 1:
139 				writel("Move not rolled.\n");
140 				break;
141 
142 			case 2:
143 				writel("Bad starting position.\n");
144 				break;
145 
146 			case 3:
147 				writel("Destination occupied.\n");
148 				break;
149 
150 			case 4:
151 				writel("Can't remove men yet.\n");
152 			}
153 			return (0);
154 		}
155 	}
156 	return (1);
157 }
158