xref: /netbsd-src/usr.bin/mail/vars.c (revision 76dfffe33547c37f8bdd446e3e4ab0f3c16cea4b)
1 /*	$NetBSD: vars.c,v 1.4 1996/06/08 19:48:45 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1980, 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. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #ifndef lint
37 #if 0
38 static char sccsid[] = "@(#)vars.c	8.1 (Berkeley) 6/6/93";
39 #else
40 static char rcsid[] = "$NetBSD: vars.c,v 1.4 1996/06/08 19:48:45 christos Exp $";
41 #endif
42 #endif /* not lint */
43 
44 #include "rcv.h"
45 #include "extern.h"
46 
47 /*
48  * Mail -- a mail program
49  *
50  * Variable handling stuff.
51  */
52 
53 /*
54  * Assign a value to a variable.
55  */
56 void
57 assign(name, value)
58 	char name[], value[];
59 {
60 	register struct var *vp;
61 	register int h;
62 
63 	h = hash(name);
64 	vp = lookup(name);
65 	if (vp == NOVAR) {
66 		vp = (struct var *) calloc(sizeof *vp, 1);
67 		vp->v_name = vcopy(name);
68 		vp->v_link = variables[h];
69 		variables[h] = vp;
70 	}
71 	else
72 		vfree(vp->v_value);
73 	vp->v_value = vcopy(value);
74 }
75 
76 /*
77  * Free up a variable string.  We do not bother to allocate
78  * strings whose value is "" since they are expected to be frequent.
79  * Thus, we cannot free same!
80  */
81 void
82 vfree(cp)
83 	char *cp;
84 {
85 	if (*cp)
86 		free(cp);
87 }
88 
89 /*
90  * Copy a variable value into permanent (ie, not collected after each
91  * command) space.  Do not bother to alloc space for ""
92  */
93 
94 char *
95 vcopy(str)
96 	char str[];
97 {
98 	char *new;
99 	unsigned len;
100 
101 	if (*str == '\0')
102 		return "";
103 	len = strlen(str) + 1;
104 	if ((new = malloc(len)) == NULL)
105 		panic("Out of memory");
106 	bcopy(str, new, (int) len);
107 	return new;
108 }
109 
110 /*
111  * Get the value of a variable and return it.
112  * Look in the environment if its not available locally.
113  */
114 
115 char *
116 value(name)
117 	char name[];
118 {
119 	register struct var *vp;
120 
121 	if ((vp = lookup(name)) == NOVAR)
122 		return(getenv(name));
123 	return(vp->v_value);
124 }
125 
126 /*
127  * Locate a variable and return its variable
128  * node.
129  */
130 
131 struct var *
132 lookup(name)
133 	register char name[];
134 {
135 	register struct var *vp;
136 
137 	for (vp = variables[hash(name)]; vp != NOVAR; vp = vp->v_link)
138 		if (*vp->v_name == *name && equal(vp->v_name, name))
139 			return(vp);
140 	return(NOVAR);
141 }
142 
143 /*
144  * Locate a group name and return it.
145  */
146 
147 struct grouphead *
148 findgroup(name)
149 	register char name[];
150 {
151 	register struct grouphead *gh;
152 
153 	for (gh = groups[hash(name)]; gh != NOGRP; gh = gh->g_link)
154 		if (*gh->g_name == *name && equal(gh->g_name, name))
155 			return(gh);
156 	return(NOGRP);
157 }
158 
159 /*
160  * Print a group out on stdout
161  */
162 void
163 printgroup(name)
164 	char name[];
165 {
166 	register struct grouphead *gh;
167 	register struct group *gp;
168 
169 	if ((gh = findgroup(name)) == NOGRP) {
170 		printf("\"%s\": not a group\n", name);
171 		return;
172 	}
173 	printf("%s\t", gh->g_name);
174 	for (gp = gh->g_list; gp != NOGE; gp = gp->ge_link)
175 		printf(" %s", gp->ge_name);
176 	putchar('\n');
177 }
178 
179 /*
180  * Hash the passed string and return an index into
181  * the variable or group hash table.
182  */
183 int
184 hash(name)
185 	register char *name;
186 {
187 	register h = 0;
188 
189 	while (*name) {
190 		h <<= 2;
191 		h += *name++;
192 	}
193 	if (h < 0 && (h = -h) < 0)
194 		h = 0;
195 	return (h % HSHSIZE);
196 }
197