1/*	$OpenBSD: lookup.c,v 1.15 2015/01/20 09:00:16 guenther Exp $	*/
2
3/*
4 * Copyright (c) 1983 Regents of the University of California.
5 * 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 <string.h>
33
34#include "client.h"
35
36	/* symbol types */
37#define VAR	1
38#define CONST	2
39
40struct syment {
41	int	s_type;
42	char	*s_name;
43	struct	namelist *s_value;
44	struct	syment *s_next;
45};
46
47static struct syment *hashtab[HASHSIZE];
48
49/*
50 * Define a variable from a command line argument.
51 */
52void
53define(char *name)
54{
55	char *cp, *s;
56	struct namelist *nl;
57	struct namelist *value;
58
59	debugmsg(DM_CALL, "define(%s)", name);
60
61	cp = strchr(name, '=');
62	if (cp == NULL)
63		value = NULL;
64	else if (cp[1] == '\0') {
65		*cp = '\0';
66		value = NULL;
67	} else if (cp[1] != '(') {
68		*cp++ = '\0';
69		value = makenl(cp);
70	} else {
71		value = NULL;
72		nl = NULL;
73		*cp++ = '\0';
74		do
75			cp++;
76		while (*cp == ' ' || *cp == '\t');
77		for (s = cp; ; s++) {
78			switch (*s) {
79			case ')':
80				*s = '\0';
81			case '\0':
82				break;
83			case ' ':
84			case '\t':
85				*s++ = '\0';
86				while (*s == ' ' || *s == '\t')
87					s++;
88				if (*s == ')')
89					*s = '\0';
90				break;
91			default:
92				continue;
93			}
94			if (nl == NULL)
95				value = nl = makenl(cp);
96			else {
97				nl->n_next = makenl(cp);
98				nl = nl->n_next;
99			}
100			if (*s == '\0')
101				break;
102			cp = s;
103		}
104	}
105	(void) lookup(name, REPLACE, value);
106}
107
108/*
109 * Lookup name in the table and return a pointer to it.
110 * LOOKUP - just do lookup, return NULL if not found.
111 * INSERT - insert name with value, error if already defined.
112 * REPLACE - insert or replace name with value.
113 */
114
115struct namelist *
116lookup(char *name, int action, struct namelist *value)
117{
118	unsigned int n;
119	char *cp;
120	struct syment *s;
121	char ebuf[BUFSIZ];
122
123	debugmsg(DM_CALL, "lookup(%s, %d, %p)", name, action, value);
124
125	n = 0;
126	for (cp = name; *cp; )
127		n += *cp++;
128	n %= HASHSIZE;
129
130	for (s = hashtab[n]; s != NULL; s = s->s_next) {
131		if (strcmp(name, s->s_name))
132			continue;
133		if (action != LOOKUP) {
134			if (action != INSERT || s->s_type != CONST) {
135				(void) snprintf(ebuf, sizeof(ebuf),
136					        "%.*s redefined",
137					        (int)(sizeof(ebuf) -
138					        sizeof(" redefined")), name);
139				yyerror(ebuf);
140			}
141		}
142		return(s->s_value);
143	}
144
145	if (action == LOOKUP) {
146		(void) snprintf(ebuf, sizeof(ebuf), "%.*s undefined",
147			        (int)(sizeof(ebuf) - sizeof(" undefined")),
148				name);
149		yyerror(ebuf);
150		return(NULL);
151	}
152
153	s = ALLOC(syment);
154	s->s_next = hashtab[n];
155	hashtab[n] = s;
156	s->s_type = action == INSERT ? VAR : CONST;
157	s->s_name = name;
158	s->s_value = value;
159
160	return(value);
161}
162