1 /* $NetBSD: hack.rumors.c,v 1.7 2009/08/12 07:28:41 dholland 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 #include <sys/cdefs.h> 65 #ifndef lint 66 __RCSID("$NetBSD: hack.rumors.c,v 1.7 2009/08/12 07:28:41 dholland Exp $"); 67 #endif /* not lint */ 68 69 #include "hack.h" /* for RUMORFILE and BSD (strchr) */ 70 #include "extern.h" 71 #define CHARSZ 8 /* number of bits in a char */ 72 73 static int n_rumors = 0; 74 static int n_used_rumors = -1; 75 static char *usedbits; 76 77 static void init_rumors(FILE *); 78 static int skipline(FILE *); 79 static void outline(FILE *); 80 static int used(int); 81 82 static void 83 init_rumors(FILE *rumf) 84 { 85 int i; 86 n_used_rumors = 0; 87 while (skipline(rumf)) 88 n_rumors++; 89 rewind(rumf); 90 i = n_rumors / CHARSZ; 91 usedbits = (char *) alloc((unsigned) (i + 1)); 92 for (; i >= 0; i--) 93 usedbits[i] = 0; 94 } 95 96 static int 97 skipline(FILE *rumf) 98 { 99 char line[COLNO]; 100 while (1) { 101 if (!fgets(line, sizeof(line), rumf)) 102 return (0); 103 if (strchr(line, '\n')) 104 return (1); 105 } 106 } 107 108 static void 109 outline(FILE *rumf) 110 { 111 char line[COLNO]; 112 char *ep; 113 if (!fgets(line, sizeof(line), rumf)) 114 return; 115 if ((ep = strchr(line, '\n')) != 0) 116 *ep = 0; 117 pline("This cookie has a scrap of paper inside! It reads: "); 118 pline(line); 119 } 120 121 void 122 outrumor(void) 123 { 124 int rn, i; 125 FILE *rumf; 126 if (n_rumors <= n_used_rumors || 127 (rumf = fopen(RUMORFILE, "r")) == (FILE *) 0) 128 return; 129 if (n_used_rumors < 0) 130 init_rumors(rumf); 131 if (!n_rumors) 132 goto none; 133 rn = rn2(n_rumors - n_used_rumors); 134 i = 0; 135 while (rn || used(i)) { 136 (void) skipline(rumf); 137 if (!used(i)) 138 rn--; 139 i++; 140 } 141 usedbits[i / CHARSZ] |= (1 << (i % CHARSZ)); 142 n_used_rumors++; 143 outline(rumf); 144 none: 145 (void) fclose(rumf); 146 } 147 148 static int 149 used(int i) 150 { 151 return (usedbits[i / CHARSZ] & (1 << (i % CHARSZ))); 152 } 153