xref: /openbsd/games/hack/hack.rumors.c (revision 17df1aa7)
1 /*	$OpenBSD: hack.rumors.c,v 1.7 2009/10/27 23:59:25 deraadt 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	<stdio.h>
65 #include	"hack.h"		/* for RUMORFILE and BSD (index) */
66 #define	CHARSZ	8			/* number of bits in a char */
67 int n_rumors = 0;
68 int n_used_rumors = -1;
69 char *usedbits;
70 
71 static void init_rumors(FILE *);
72 static int  skipline(FILE *);
73 static void outline(FILE *);
74 static int  used(int);
75 
76 static void
77 init_rumors(FILE *rumf)
78 {
79 	int i;
80 
81 	n_used_rumors = 0;
82 	while(skipline(rumf)) n_rumors++;
83 	rewind(rumf);
84 	i = n_rumors/CHARSZ;
85 	usedbits = (char *) alloc((unsigned)(i+1));
86 	for( ; i>=0; i--) usedbits[i] = 0;
87 }
88 
89 static int
90 skipline(FILE *rumf)
91 {
92 	char line[COLNO];
93 
94 	while(1) {
95 		if(!fgets(line, sizeof(line), rumf)) return(0);
96 		if(strchr(line, '\n')) return(1);
97 	}
98 }
99 
100 static void
101 outline(FILE *rumf)
102 {
103 	char line[COLNO];
104 
105 	if(!fgets(line, sizeof(line), rumf)) return;
106 	line[strcspn(line, "\n")] = '\0';
107 	pline("This cookie has a scrap of paper inside! It reads: ");
108 	pline(line);
109 }
110 
111 void
112 outrumor()
113 {
114 	int rn,i;
115 	FILE *rumf;
116 
117 	if(n_rumors <= n_used_rumors ||
118 	  (rumf = fopen(RUMORFILE, "r")) == (FILE *) 0) return;
119 	if(n_used_rumors < 0) init_rumors(rumf);
120 	if(!n_rumors) goto none;
121 	rn = rn2(n_rumors - n_used_rumors);
122 	i = 0;
123 	while(rn || used(i)) {
124 		(void) skipline(rumf);
125 		if(!used(i)) rn--;
126 		i++;
127 	}
128 	usedbits[i/CHARSZ] |= (1 << (i % CHARSZ));
129 	n_used_rumors++;
130 	outline(rumf);
131 none:
132 	(void) fclose(rumf);
133 }
134 
135 static int
136 used(int i)
137 {
138 	return(usedbits[i/CHARSZ] & (1 << (i % CHARSZ)));
139 }
140