xref: /titanic_52/usr/src/cmd/cmd-inet/usr.bin/rdist/lookup.c (revision dd51520e127b452179a2ce4ea3bd8dee949f9afe)
1 /*
2  * Copyright (c) 1983 Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms are permitted
6  * provided that the above copyright notice and this paragraph are
7  * duplicated in all such forms and that any documentation,
8  * advertising materials, and other materials related to such
9  * distribution and use acknowledge that the software was developed
10  * by the University of California, Berkeley.  The name of the
11  * University may not be used to endorse or promote products derived
12  * from this software without specific prior written permission.
13  *
14  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
15  * Use is subject to license terms.
16  */
17 #pragma ident	"%Z%%M%	%I%	%E% SMI"
18 
19 #include "defs.h"
20 
21 	/* symbol types */
22 #define VAR	1
23 #define CONST	2
24 
25 struct syment {
26 	int	s_type;
27 	char	*s_name;
28 	struct	namelist *s_value;
29 	struct	syment *s_next;
30 };
31 
32 static struct syment *hashtab[HASHSIZE];
33 
34 /*
35  * Define a variable from a command line argument.
36  */
37 void
38 define(name)
39 	char *name;
40 {
41 	register char *cp, *s;
42 	register struct namelist *nl;
43 	struct namelist *value;
44 
45 	if (debug)
46 		printf("define(%s)\n", name);
47 
48 	cp = index(name, '=');
49 	if (cp == NULL)
50 		value = NULL;
51 	else if (cp[1] == '\0') {
52 		*cp = '\0';
53 		value = NULL;
54 	} else if (cp[1] != '(') {
55 		*cp++ = '\0';
56 		value = makenl(cp);
57 	} else {
58 		nl = NULL;
59 		*cp++ = '\0';
60 		do
61 			cp++;
62 		while (*cp == ' ' || *cp == '\t');
63 		for (s = cp; ; s++) {
64 			switch (*s) {
65 			case ')':
66 				*s = '\0';
67 			case '\0':
68 				break;
69 			case ' ':
70 			case '\t':
71 				*s++ = '\0';
72 				while (*s == ' ' || *s == '\t')
73 					s++;
74 				if (*s == ')')
75 					*s = '\0';
76 				break;
77 			default:
78 				continue;
79 			}
80 			if (nl == NULL)
81 				value = nl = makenl(cp);
82 			else {
83 				nl->n_next = makenl(cp);
84 				nl = nl->n_next;
85 			}
86 			if (*s == '\0')
87 				break;
88 			cp = s;
89 		}
90 	}
91 	(void) lookup(name, REPLACE, value);
92 }
93 
94 /*
95  * Lookup name in the table and return a pointer to it.
96  * LOOKUP - just do lookup, return NULL if not found.
97  * INSERT - insert name with value, error if already defined.
98  * REPLACE - insert or replace name with value.
99  */
100 
101 struct namelist *
102 lookup(name, action, value)
103 	char *name;
104 	int action;
105 	struct namelist *value;
106 {
107 	register unsigned n;
108 	register char *cp;
109 	register struct syment *s;
110 	char buf[256];
111 
112 	if (debug)
113 		printf("lookup(%s, %d, %x)\n", name, action, value);
114 
115 	n = 0;
116 	for (cp = name; *cp; )
117 		n += *cp++;
118 	n %= HASHSIZE;
119 
120 	for (s = hashtab[n]; s != NULL; s = s->s_next) {
121 		if (strcmp(name, s->s_name))
122 			continue;
123 		if (action != LOOKUP) {
124 			if (action != INSERT || s->s_type != CONST) {
125 				(void)sprintf(buf, "%.*s redefined",
126 				      sizeof(buf) - sizeof(" redefined"), name);
127 				yyerror(buf);
128 			}
129 		}
130 		return(s->s_value);
131 	}
132 
133 	if (action == LOOKUP) {
134 		(void)sprintf(buf, "%.*s undefined",
135 			sizeof(buf) - sizeof(" undefined"), name);
136 		yyerror(buf);
137 		return(NULL);
138 	}
139 
140 	s = ALLOC(syment);
141 	if (s == NULL)
142 		fatal("ran out of memory\n");
143 	s->s_next = hashtab[n];
144 	hashtab[n] = s;
145 	s->s_type = action == INSERT ? VAR : CONST;
146 	s->s_name = name;
147 	s->s_value = value;
148 	return(value);
149 }
150