1 /* $NetBSD: allow.c,v 1.4 1997/10/10 08:59:41 lukem 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. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 #ifndef lint 38 #if 0 39 static char sccsid[] = "@(#)allow.c 8.1 (Berkeley) 5/31/93"; 40 #else 41 __RCSID("$NetBSD: allow.c,v 1.4 1997/10/10 08:59:41 lukem Exp $"); 42 #endif 43 #endif /* not lint */ 44 45 #include "back.h" 46 47 int 48 movallow() 49 { 50 int i, m, iold; 51 int r; 52 53 if (d0) 54 swap; 55 m = (D0 == D1 ? 4 : 2); 56 for (i = 0; i < 4; i++) 57 p[i] = bar; 58 i = iold = 0; 59 while (i < m) { 60 if (*offptr == 15) 61 break; 62 h[i] = 0; 63 if (board[bar]) { 64 if (i == 1 || m == 4) 65 g[i] = bar + cturn * D1; 66 else 67 g[i] = bar + cturn * D0; 68 if ((r = makmove(i)) != 0) { 69 if (d0 || m == 4) 70 break; 71 swap; 72 movback(i); 73 if (i > iold) 74 iold = i; 75 for (i = 0; i < 4; i++) 76 p[i] = bar; 77 i = 0; 78 } else 79 i++; 80 continue; 81 } 82 if ((p[i] += cturn) == home) { 83 if (i > iold) 84 iold = i; 85 if (m == 2 && i) { 86 movback(i); 87 p[i--] = bar; 88 if (p[i] != bar) 89 continue; 90 else 91 break; 92 } 93 if (d0 || m == 4) 94 break; 95 swap; 96 movback(i); 97 for (i = 0; i < 4; i++) 98 p[i] = bar; 99 i = 0; 100 continue; 101 } 102 if (i == 1 || m == 4) 103 g[i] = p[i] + cturn * D1; 104 else 105 g[i] = p[i] + cturn * D0; 106 if (g[i] * cturn > home) { 107 if (*offptr >= 0) 108 g[i] = home; 109 else 110 continue; 111 } 112 if (board[p[i]] * cturn > 0 && (r = makmove(i)) == 0) 113 i++; 114 } 115 movback(i); 116 return (iold > i ? iold : i); 117 } 118