1 #include	"mk.h"
2 
3 #define	NHASH	4099
4 #define	HASHMUL	79L	/* this is a good value */
5 static Symtab *hash[NHASH];
6 
7 void
8 syminit(void)
9 {
10 	Symtab **s, *ss;
11 
12 	for(s = hash; s < &hash[NHASH]; s++){
13 		for(ss = *s; ss; ss = ss->next)
14 			free((char *)ss);
15 		*s = 0;
16 	}
17 }
18 
19 Symtab *
20 symlook(char *sym, int space, void *install)
21 {
22 	long h;
23 	char *p;
24 	Symtab *s;
25 
26 	for(p = sym, h = space; *p; h += *p++)
27 		h *= HASHMUL;
28 	if(h < 0)
29 		h = ~h;
30 	h %= NHASH;
31 	for(s = hash[h]; s; s = s->next)
32 		if((s->space == space) && (strcmp(s->name, sym) == 0))
33 			return(s);
34 	if(install == 0)
35 		return(0);
36 	s = (Symtab *)Malloc(sizeof(Symtab));
37 	s->space = space;
38 	s->name = sym;
39 	s->value = install;
40 	s->next = hash[h];
41 	hash[h] = s;
42 	return(s);
43 }
44 
45 void
46 symdel(char *sym, int space)
47 {
48 	long h;
49 	char *p;
50 	Symtab *s, *ls;
51 
52 	/* multiple memory leaks */
53 
54 	for(p = sym, h = space; *p; h += *p++)
55 		h *= HASHMUL;
56 	if(h < 0)
57 		h = ~h;
58 	h %= NHASH;
59 	for(s = hash[h], ls = 0; s; ls = s, s = s->next)
60 		if((s->space == space) && (strcmp(s->name, sym) == 0)){
61 			if(ls)
62 				ls->next = s->next;
63 			else
64 				hash[h] = s->next;
65 			free((char *)s);
66 		}
67 }
68 
69 void
70 symtraverse(int space, void (*fn)(Symtab*))
71 {
72 	Symtab **s, *ss;
73 
74 	for(s = hash; s < &hash[NHASH]; s++)
75 		for(ss = *s; ss; ss = ss->next)
76 			if(ss->space == space)
77 				(*fn)(ss);
78 }
79 
80 void
81 symstat(void)
82 {
83 	Symtab **s, *ss;
84 	int n;
85 	int l[1000];
86 
87 	memset((char *)l, 0, sizeof(l));
88 	for(s = hash; s < &hash[NHASH]; s++){
89 		for(ss = *s, n = 0; ss; ss = ss->next)
90 			n++;
91 		l[n]++;
92 	}
93 	for(n = 0; n < 1000; n++)
94 		if(l[n]) Bprint(&bout, "%ld of length %d\n", l[n], n);
95 }