1 /* $NetBSD: hack.rumors.c,v 1.9 2011/08/06 20:18:26 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 1.9 2011/08/06 20:18:26 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
init_rumors(FILE * rumf)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 = alloc(i + 1);
92 for (; i >= 0; i--)
93 usedbits[i] = 0;
94 }
95
96 static int
skipline(FILE * rumf)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
outline(FILE * rumf)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("%s", line);
119 }
120
121 void
outrumor(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
used(int i)149 used(int i)
150 {
151 return (usedbits[i / CHARSZ] & (1 << (i % CHARSZ)));
152 }
153