1 /* $NetBSD: lookup.c,v 1.9 2009/04/13 04:35:36 lukem Exp $ */
2
3 /*
4 * Copyright (c) 1983, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 #ifndef lint
34 #if 0
35 static char sccsid[] = "@(#)lookup.c 8.1 (Berkeley) 6/9/93";
36 #else
37 __RCSID("$NetBSD: lookup.c,v 1.9 2009/04/13 04:35:36 lukem Exp $");
38 #endif
39 #endif /* not lint */
40
41 #include "defs.h"
42
43 /* symbol types */
44 #define VAR 1
45 #define CONST 2
46
47 struct syment {
48 int s_type;
49 char *s_name;
50 struct namelist *s_value;
51 struct syment *s_next;
52 };
53
54 static struct syment *hashtab[HASHSIZE];
55
56 /*
57 * Define a variable from a command line argument.
58 */
59 void
define(char * name)60 define(char *name)
61 {
62 char *cp, *s;
63 struct namelist *nl;
64 struct namelist *value;
65
66 value = NULL;
67
68 if (debug)
69 printf("define(%s)\n", name);
70
71 cp = strchr(name, '=');
72 if (cp == NULL)
73 value = NULL;
74 else if (cp[1] == '\0') {
75 *cp = '\0';
76 value = NULL;
77 } else if (cp[1] != '(') {
78 *cp++ = '\0';
79 value = makenl(cp);
80 } else {
81 nl = NULL;
82 *cp++ = '\0';
83 do
84 cp++;
85 while (*cp == ' ' || *cp == '\t');
86 for (s = cp; ; s++) {
87 switch (*s) {
88 case ')':
89 *s = '\0';
90 case '\0':
91 break;
92 case ' ':
93 case '\t':
94 *s++ = '\0';
95 while (*s == ' ' || *s == '\t')
96 s++;
97 if (*s == ')')
98 *s = '\0';
99 break;
100 default:
101 continue;
102 }
103 if (nl == NULL)
104 value = nl = makenl(cp);
105 else {
106 nl->n_next = makenl(cp);
107 nl = nl->n_next;
108 }
109 if (*s == '\0')
110 break;
111 cp = s;
112 }
113 }
114 (void) lookup(name, REPLACE, value);
115 }
116
117 /*
118 * Lookup name in the table and return a pointer to it.
119 * LOOKUP - just do lookup, return NULL if not found.
120 * INSERT - insert name with value, error if already defined.
121 * REPLACE - insert or replace name with value.
122 */
123
124 struct namelist *
lookup(char * name,int action,struct namelist * value)125 lookup(char *name, int action, struct namelist *value)
126 {
127 unsigned n;
128 char *cp;
129 struct syment *s;
130 char lbuf[256];
131
132 if (debug)
133 printf("lookup(%s, %d, %lx)\n", name, action, (long)value);
134
135 n = 0;
136 for (cp = name; *cp; )
137 n += *cp++;
138 n %= HASHSIZE;
139
140 for (s = hashtab[n]; s != NULL; s = s->s_next) {
141 if (strcmp(name, s->s_name))
142 continue;
143 if (action != LOOKUP) {
144 if (action != INSERT || s->s_type != CONST) {
145 (void)snprintf(lbuf, sizeof(lbuf),
146 "%s redefined", name);
147 yyerror(lbuf);
148 }
149 }
150 return(s->s_value);
151 }
152
153 if (action == LOOKUP) {
154 (void)snprintf(lbuf, sizeof(lbuf), "%s undefined", name);
155 yyerror(lbuf);
156 return(NULL);
157 }
158
159 s = ALLOC(syment);
160 if (s == NULL)
161 fatal("ran out of memory\n");
162 s->s_next = hashtab[n];
163 hashtab[n] = s;
164 s->s_type = action == INSERT ? VAR : CONST;
165 s->s_name = name;
166 s->s_value = value;
167 return(value);
168 }
169