1 /* $OpenBSD: warshall.c,v 1.9 2009/10/27 23:59:50 deraadt Exp $ */ 2 /* $NetBSD: warshall.c,v 1.4 1996/03/19 03:21:51 jtc Exp $ */ 3 4 /* 5 * Copyright (c) 1989 The Regents of the University of California. 6 * All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * Robert Paul Corbett. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. 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 "defs.h" 37 38 void transitive_closure(unsigned int *, int); 39 40 void 41 transitive_closure(unsigned int *R, int n) 42 { 43 int rowsize; 44 unsigned i; 45 unsigned *rowj; 46 unsigned *rp; 47 unsigned *rend; 48 unsigned *ccol; 49 unsigned *relend; 50 unsigned *cword; 51 unsigned *rowi; 52 53 rowsize = WORDSIZE(n); 54 relend = R + n*rowsize; 55 56 cword = R; 57 i = 0; 58 rowi = R; 59 while (rowi < relend) 60 { 61 ccol = cword; 62 rowj = R; 63 64 while (rowj < relend) 65 { 66 if (*ccol & (1 << i)) 67 { 68 rp = rowi; 69 rend = rowj + rowsize; 70 while (rowj < rend) 71 *rowj++ |= *rp++; 72 } 73 else 74 { 75 rowj += rowsize; 76 } 77 78 ccol += rowsize; 79 } 80 81 if (++i >= BITS_PER_WORD) 82 { 83 i = 0; 84 cword++; 85 } 86 87 rowi += rowsize; 88 } 89 } 90 91 void 92 reflexive_transitive_closure(unsigned int *R, int n) 93 { 94 int rowsize; 95 unsigned i; 96 unsigned *rp; 97 unsigned *relend; 98 99 transitive_closure(R, n); 100 101 rowsize = WORDSIZE(n); 102 relend = R + n*rowsize; 103 104 i = 0; 105 rp = R; 106 while (rp < relend) 107 { 108 *rp |= (1 << i); 109 if (++i >= BITS_PER_WORD) 110 { 111 i = 0; 112 rp++; 113 } 114 115 rp += rowsize; 116 } 117 } 118