xref: /netbsd-src/usr.bin/mail/vars.c (revision ce63d6c20fc4ec8ddc95c84bb229e3c4ecf82b69)
1 /*
2  * Copyright (c) 1980 Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 static char sccsid[] = "@(#)vars.c	5.6 (Berkeley) 6/1/90";
36 #endif /* not lint */
37 
38 #include "rcv.h"
39 
40 /*
41  * Mail -- a mail program
42  *
43  * Variable handling stuff.
44  */
45 
46 /*
47  * Assign a value to a variable.
48  */
49 
50 assign(name, value)
51 	char name[], value[];
52 {
53 	register struct var *vp;
54 	register int h;
55 
56 	h = hash(name);
57 	vp = lookup(name);
58 	if (vp == NOVAR) {
59 		vp = (struct var *) calloc(sizeof *vp, 1);
60 		vp->v_name = vcopy(name);
61 		vp->v_link = variables[h];
62 		variables[h] = vp;
63 	}
64 	else
65 		vfree(vp->v_value);
66 	vp->v_value = vcopy(value);
67 }
68 
69 /*
70  * Free up a variable string.  We do not bother to allocate
71  * strings whose value is "" since they are expected to be frequent.
72  * Thus, we cannot free same!
73  */
74 
75 vfree(cp)
76 	char *cp;
77 {
78 	if (*cp)
79 		free(cp);
80 }
81 
82 /*
83  * Copy a variable value into permanent (ie, not collected after each
84  * command) space.  Do not bother to alloc space for ""
85  */
86 
87 char *
88 vcopy(str)
89 	char str[];
90 {
91 	char *new;
92 	unsigned len;
93 
94 	if (*str == '\0')
95 		return "";
96 	len = strlen(str) + 1;
97 	if ((new = malloc(len)) == NULL)
98 		panic("Out of memory");
99 	bcopy(str, new, (int) len);
100 	return new;
101 }
102 
103 /*
104  * Get the value of a variable and return it.
105  * Look in the environment if its not available locally.
106  */
107 
108 char *
109 value(name)
110 	char name[];
111 {
112 	register struct var *vp;
113 
114 	if ((vp = lookup(name)) == NOVAR)
115 		return(getenv(name));
116 	return(vp->v_value);
117 }
118 
119 /*
120  * Locate a variable and return its variable
121  * node.
122  */
123 
124 struct var *
125 lookup(name)
126 	register char name[];
127 {
128 	register struct var *vp;
129 
130 	for (vp = variables[hash(name)]; vp != NOVAR; vp = vp->v_link)
131 		if (*vp->v_name == *name && equal(vp->v_name, name))
132 			return(vp);
133 	return(NOVAR);
134 }
135 
136 /*
137  * Locate a group name and return it.
138  */
139 
140 struct grouphead *
141 findgroup(name)
142 	register char name[];
143 {
144 	register struct grouphead *gh;
145 
146 	for (gh = groups[hash(name)]; gh != NOGRP; gh = gh->g_link)
147 		if (*gh->g_name == *name && equal(gh->g_name, name))
148 			return(gh);
149 	return(NOGRP);
150 }
151 
152 /*
153  * Print a group out on stdout
154  */
155 
156 printgroup(name)
157 	char name[];
158 {
159 	register struct grouphead *gh;
160 	register struct group *gp;
161 
162 	if ((gh = findgroup(name)) == NOGRP) {
163 		printf("\"%s\": not a group\n", name);
164 		return;
165 	}
166 	printf("%s\t", gh->g_name);
167 	for (gp = gh->g_list; gp != NOGE; gp = gp->ge_link)
168 		printf(" %s", gp->ge_name);
169 	putchar('\n');
170 }
171 
172 /*
173  * Hash the passed string and return an index into
174  * the variable or group hash table.
175  */
176 
177 hash(name)
178 	register char *name;
179 {
180 	register h = 0;
181 
182 	while (*name) {
183 		h <<= 2;
184 		h += *name++;
185 	}
186 	if (h < 0 && (h = -h) < 0)
187 		h = 0;
188 	return (h % HSHSIZE);
189 }
190