xref: /netbsd-src/usr.bin/mail/vars.c (revision c0179c282a5968435315a82f4128c61372c68fc3)
1 /*	$NetBSD: vars.c,v 1.16 2006/10/31 20:07:33 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. 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[] = "@(#)vars.c	8.1 (Berkeley) 6/6/93";
36 #else
37 __RCSID("$NetBSD: vars.c,v 1.16 2006/10/31 20:07:33 christos Exp $");
38 #endif
39 #endif /* not lint */
40 
41 #include "rcv.h"
42 #include <util.h>
43 
44 #include "extern.h"
45 
46 /*
47  * Mail -- a mail program
48  *
49  * Variable handling stuff.
50  */
51 
52 /*
53  * Assign a value to a variable.
54  */
55 void
56 assign(const char name[], const char values[])
57 {
58 	struct var *vp;
59 	int h;
60 
61 	h = hash(name);
62 	vp = lookup(name);
63 	if (vp == NULL) {
64 		vp = (struct var *) ecalloc(1, sizeof *vp);
65 		vp->v_name = vcopy(name);
66 		vp->v_link = variables[h];
67 		variables[h] = vp;
68 	}
69 	else
70                 v_free(vp->v_value);
71 	vp->v_value = vcopy(values);
72 }
73 
74 /*
75  * Free up a variable string.  We do not bother to allocate
76  * strings whose value is "" since they are expected to be frequent.
77  * Thus, we cannot free same!
78  */
79 void
80 v_free(char *cp)
81 {
82 	if (*cp)
83 		free(cp);
84 }
85 
86 /*
87  * Copy a variable value into permanent (ie, not collected after each
88  * command) space.  Do not bother to alloc space for ""
89  */
90 
91 char *
92 vcopy(const char str[])
93 {
94 	char *new;
95 	size_t len;
96 
97 	if (*str == '\0')
98 		return estrdup("");
99 	len = strlen(str) + 1;
100 	new = emalloc(len);
101 	(void)memmove(new, str, len);
102 	return new;
103 }
104 
105 /*
106  * Get the value of a variable and return it.
107  * Look in the environment if its not available locally.
108  */
109 
110 char *
111 value(const char name[])
112 {
113 	struct var *vp;
114 
115 	if ((vp = lookup(name)) == NULL)
116 		return(getenv(name));
117 	return(vp->v_value);
118 }
119 
120 /*
121  * Locate a variable and return its variable
122  * node.
123  */
124 
125 struct var *
126 lookup(const char name[])
127 {
128 	struct var *vp;
129 
130 	for (vp = variables[hash(name)]; vp != NULL; vp = vp->v_link)
131 		if (*vp->v_name == *name && equal(vp->v_name, name))
132 			return(vp);
133 	return(NULL);
134 }
135 
136 /*
137  * Locate a group name and return it.
138  */
139 
140 struct grouphead *
141 findgroup(char name[])
142 {
143 	struct grouphead *gh;
144 
145 	for (gh = groups[hash(name)]; gh != NULL; gh = gh->g_link)
146 		if (*gh->g_name == *name && equal(gh->g_name, name))
147 			return(gh);
148 	return(NULL);
149 }
150 
151 /*
152  * Print a group out on stdout
153  */
154 void
155 printgroup(char name[])
156 {
157 	struct grouphead *gh;
158 	struct group *gp;
159 
160 	if ((gh = findgroup(name)) == NULL) {
161 		(void)printf("\"%s\": not a group\n", name);
162 		return;
163 	}
164 	(void)printf("%s\t", gh->g_name);
165 	for (gp = gh->g_list; gp != NULL; gp = gp->ge_link)
166 		(void)printf(" %s", gp->ge_name);
167 	(void)putchar('\n');
168 }
169 
170 /*
171  * Hash the passed string and return an index into
172  * the variable or group hash table.
173  */
174 int
175 hash(const char *name)
176 {
177 	int h = 0;
178 
179 	while (*name) {
180 		h <<= 2;
181 		h += *name++;
182 	}
183 	if (h < 0 && (h = -h) < 0)
184 		h = 0;
185 	return (h % HSHSIZE);
186 }
187