1 /* $NetBSD: symtab.c,v 1.8 2015/01/03 23:22:52 christos Exp $ */
2
3 /* Id: symtab.c,v 1.11 2014/03/26 00:17:09 Tom.Shields Exp */
4
5 #include "defs.h"
6
7 #include <sys/cdefs.h>
8 __RCSID("$NetBSD: symtab.c,v 1.8 2015/01/03 23:22:52 christos Exp $");
9
10 /* TABLE_SIZE is the number of entries in the symbol table. */
11 /* TABLE_SIZE must be a power of two. */
12
13 #define TABLE_SIZE 1024
14
15 static bucket **symbol_table = 0;
16 bucket *first_symbol;
17 bucket *last_symbol;
18
19 static int
hash(const char * name)20 hash(const char *name)
21 {
22 const char *s;
23 int c, k;
24
25 assert(name && *name);
26 s = name;
27 k = *s;
28 while ((c = *++s) != 0)
29 k = (31 * k + c) & (TABLE_SIZE - 1);
30
31 return (k);
32 }
33
34 bucket *
make_bucket(const char * name)35 make_bucket(const char *name)
36 {
37 bucket *bp;
38
39 assert(name != 0);
40
41 bp = TMALLOC(bucket, 1);
42 NO_SPACE(bp);
43
44 bp->link = 0;
45 bp->next = 0;
46
47 bp->name = TMALLOC(char, strlen(name) + 1);
48 NO_SPACE(bp->name);
49
50 bp->tag = 0;
51 bp->value = UNDEFINED;
52 bp->index = 0;
53 bp->prec = 0;
54 bp->class = UNKNOWN;
55 bp->assoc = TOKEN;
56 #if defined(YYBTYACC)
57 bp->args = -1;
58 bp->argnames = 0;
59 bp->argtags = 0;
60 bp->destructor = 0;
61 #endif
62 strcpy(bp->name, name);
63
64 return (bp);
65 }
66
67 bucket *
lookup(const char * name)68 lookup(const char *name)
69 {
70 bucket *bp, **bpp;
71
72 bpp = symbol_table + hash(name);
73 bp = *bpp;
74
75 while (bp)
76 {
77 if (strcmp(name, bp->name) == 0)
78 return (bp);
79 bpp = &bp->link;
80 bp = *bpp;
81 }
82
83 *bpp = bp = make_bucket(name);
84 last_symbol->next = bp;
85 last_symbol = bp;
86
87 return (bp);
88 }
89
90 void
create_symbol_table(void)91 create_symbol_table(void)
92 {
93 int i;
94 bucket *bp;
95
96 symbol_table = TMALLOC(bucket *, TABLE_SIZE);
97 NO_SPACE(symbol_table);
98
99 for (i = 0; i < TABLE_SIZE; i++)
100 symbol_table[i] = 0;
101
102 bp = make_bucket("error");
103 bp->index = 1;
104 bp->class = TERM;
105
106 first_symbol = bp;
107 last_symbol = bp;
108 symbol_table[hash("error")] = bp;
109 }
110
111 void
free_symbol_table(void)112 free_symbol_table(void)
113 {
114 FREE(symbol_table);
115 symbol_table = 0;
116 }
117
118 void
free_symbols(void)119 free_symbols(void)
120 {
121 bucket *p, *q;
122
123 for (p = first_symbol; p; p = q)
124 {
125 q = p->next;
126 FREE(p);
127 }
128 }
129