hack.rumors.c revision 1.1 1 1.1 cgd /* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
2 1.1 cgd /* hack.rumors.c - version 1.0.3 */
3 1.1 cgd
4 1.1 cgd #include <stdio.h>
5 1.1 cgd #include "hack.h" /* for RUMORFILE and BSD (index) */
6 1.1 cgd #define CHARSZ 8 /* number of bits in a char */
7 1.1 cgd extern long *alloc();
8 1.1 cgd extern char *index();
9 1.1 cgd int n_rumors = 0;
10 1.1 cgd int n_used_rumors = -1;
11 1.1 cgd char *usedbits;
12 1.1 cgd
13 1.1 cgd init_rumors(rumf) register FILE *rumf; {
14 1.1 cgd register int i;
15 1.1 cgd n_used_rumors = 0;
16 1.1 cgd while(skipline(rumf)) n_rumors++;
17 1.1 cgd rewind(rumf);
18 1.1 cgd i = n_rumors/CHARSZ;
19 1.1 cgd usedbits = (char *) alloc((unsigned)(i+1));
20 1.1 cgd for( ; i>=0; i--) usedbits[i] = 0;
21 1.1 cgd }
22 1.1 cgd
23 1.1 cgd skipline(rumf) register FILE *rumf; {
24 1.1 cgd char line[COLNO];
25 1.1 cgd while(1) {
26 1.1 cgd if(!fgets(line, sizeof(line), rumf)) return(0);
27 1.1 cgd if(index(line, '\n')) return(1);
28 1.1 cgd }
29 1.1 cgd }
30 1.1 cgd
31 1.1 cgd outline(rumf) register FILE *rumf; {
32 1.1 cgd char line[COLNO];
33 1.1 cgd register char *ep;
34 1.1 cgd if(!fgets(line, sizeof(line), rumf)) return;
35 1.1 cgd if((ep = index(line, '\n')) != 0) *ep = 0;
36 1.1 cgd pline("This cookie has a scrap of paper inside! It reads: ");
37 1.1 cgd pline(line);
38 1.1 cgd }
39 1.1 cgd
40 1.1 cgd outrumor(){
41 1.1 cgd register int rn,i;
42 1.1 cgd register FILE *rumf;
43 1.1 cgd if(n_rumors <= n_used_rumors ||
44 1.1 cgd (rumf = fopen(RUMORFILE, "r")) == (FILE *) 0) return;
45 1.1 cgd if(n_used_rumors < 0) init_rumors(rumf);
46 1.1 cgd if(!n_rumors) goto none;
47 1.1 cgd rn = rn2(n_rumors - n_used_rumors);
48 1.1 cgd i = 0;
49 1.1 cgd while(rn || used(i)) {
50 1.1 cgd (void) skipline(rumf);
51 1.1 cgd if(!used(i)) rn--;
52 1.1 cgd i++;
53 1.1 cgd }
54 1.1 cgd usedbits[i/CHARSZ] |= (1 << (i % CHARSZ));
55 1.1 cgd n_used_rumors++;
56 1.1 cgd outline(rumf);
57 1.1 cgd none:
58 1.1 cgd (void) fclose(rumf);
59 1.1 cgd }
60 1.1 cgd
61 1.1 cgd used(i) register int i; {
62 1.1 cgd return(usedbits[i/CHARSZ] & (1 << (i % CHARSZ)));
63 1.1 cgd }
64