1 /* $OpenBSD: hack.rumors.c,v 1.6 2007/09/11 15:21:05 gilles Exp $ */ 2 3 /* 4 * Copyright (c) 1985, Stichting Centrum voor Wiskunde en Informatica, 5 * Amsterdam 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions are 10 * met: 11 * 12 * - Redistributions of source code must retain the above copyright notice, 13 * this list of conditions and the following disclaimer. 14 * 15 * - Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * - Neither the name of the Stichting Centrum voor Wiskunde en 20 * Informatica, nor the names of its contributors may be used to endorse or 21 * promote products derived from this software without specific prior 22 * written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS 25 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 26 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A 27 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER 28 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 29 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 30 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 31 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 32 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 33 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 34 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 35 */ 36 37 /* 38 * Copyright (c) 1982 Jay Fenlason <hack@gnu.org> 39 * All rights reserved. 40 * 41 * Redistribution and use in source and binary forms, with or without 42 * modification, are permitted provided that the following conditions 43 * are met: 44 * 1. Redistributions of source code must retain the above copyright 45 * notice, this list of conditions and the following disclaimer. 46 * 2. Redistributions in binary form must reproduce the above copyright 47 * notice, this list of conditions and the following disclaimer in the 48 * documentation and/or other materials provided with the distribution. 49 * 3. The name of the author may not be used to endorse or promote products 50 * derived from this software without specific prior written permission. 51 * 52 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, 53 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY 54 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 55 * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 56 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 57 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 58 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 59 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 60 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 61 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 62 */ 63 64 #ifndef lint 65 static const char rcsid[] = "$OpenBSD: hack.rumors.c,v 1.6 2007/09/11 15:21:05 gilles Exp $"; 66 #endif /* not lint */ 67 68 #include <stdio.h> 69 #include "hack.h" /* for RUMORFILE and BSD (index) */ 70 #define CHARSZ 8 /* number of bits in a char */ 71 int n_rumors = 0; 72 int n_used_rumors = -1; 73 char *usedbits; 74 75 static void init_rumors(FILE *); 76 static int skipline(FILE *); 77 static void outline(FILE *); 78 static int used(int); 79 80 static void 81 init_rumors(FILE *rumf) 82 { 83 int i; 84 85 n_used_rumors = 0; 86 while(skipline(rumf)) n_rumors++; 87 rewind(rumf); 88 i = n_rumors/CHARSZ; 89 usedbits = (char *) alloc((unsigned)(i+1)); 90 for( ; i>=0; i--) usedbits[i] = 0; 91 } 92 93 static int 94 skipline(FILE *rumf) 95 { 96 char line[COLNO]; 97 98 while(1) { 99 if(!fgets(line, sizeof(line), rumf)) return(0); 100 if(strchr(line, '\n')) return(1); 101 } 102 } 103 104 static void 105 outline(FILE *rumf) 106 { 107 char line[COLNO]; 108 109 if(!fgets(line, sizeof(line), rumf)) return; 110 line[strcspn(line, "\n")] = '\0'; 111 pline("This cookie has a scrap of paper inside! It reads: "); 112 pline(line); 113 } 114 115 void 116 outrumor() 117 { 118 int rn,i; 119 FILE *rumf; 120 121 if(n_rumors <= n_used_rumors || 122 (rumf = fopen(RUMORFILE, "r")) == (FILE *) 0) return; 123 if(n_used_rumors < 0) init_rumors(rumf); 124 if(!n_rumors) goto none; 125 rn = rn2(n_rumors - n_used_rumors); 126 i = 0; 127 while(rn || used(i)) { 128 (void) skipline(rumf); 129 if(!used(i)) rn--; 130 i++; 131 } 132 usedbits[i/CHARSZ] |= (1 << (i % CHARSZ)); 133 n_used_rumors++; 134 outline(rumf); 135 none: 136 (void) fclose(rumf); 137 } 138 139 static int 140 used(int i) 141 { 142 return(usedbits[i/CHARSZ] & (1 << (i % CHARSZ))); 143 } 144