vars.c revision 330897 
1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
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 * 4. 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#ifndef lint
33#if 0
34static char sccsid[] = "@(#)vars.c	8.1 (Berkeley) 6/6/93";
35#endif
36#endif /* not lint */
37#include <sys/cdefs.h>
38__FBSDID("$FreeBSD: stable/11/usr.bin/mail/vars.c 330897 2018-03-14 03:19:51Z eadler $");
39
40#include "rcv.h"
41#include "extern.h"
42
43/*
44 * Mail -- a mail program
45 *
46 * Variable handling stuff.
47 */
48
49/*
50 * Assign a value to a variable.
51 */
52void
53assign(const char *name, const char *value)
54{
55	struct var *vp;
56	int h;
57
58	h = hash(name);
59	vp = lookup(name);
60	if (vp == NULL) {
61		if ((vp = calloc(1, sizeof(*vp))) == NULL)
62			err(1, "Out of memory");
63		vp->v_name = vcopy(name);
64		vp->v_link = variables[h];
65		variables[h] = vp;
66	}
67	else
68		vfree(vp->v_value);
69	vp->v_value = vcopy(value);
70}
71
72/*
73 * Free up a variable string.  We do not bother to allocate
74 * strings whose value is "" since they are expected to be frequent.
75 * Thus, we cannot free same!
76 */
77void
78vfree(char *cp)
79{
80	if (*cp != '\0')
81		(void)free(cp);
82}
83
84/*
85 * Copy a variable value into permanent (ie, not collected after each
86 * command) space.  Do not bother to alloc space for ""
87 */
88
89char *
90vcopy(const char *str)
91{
92	char *new;
93	unsigned len;
94
95	if (*str == '\0')
96		return ("");
97	len = strlen(str) + 1;
98	if ((new = malloc(len)) == NULL)
99		err(1, "Out of memory");
100	bcopy(str, new, (int)len);
101	return (new);
102}
103
104/*
105 * Get the value of a variable and return it.
106 * Look in the environment if its not available locally.
107 */
108
109char *
110value(const char *name)
111{
112	struct var *vp;
113
114	if ((vp = lookup(name)) == NULL)
115		return (getenv(name));
116	return (vp->v_value);
117}
118
119/*
120 * Locate a variable and return its variable
121 * node.
122 */
123
124struct var *
125lookup(const char *name)
126{
127	struct var *vp;
128
129	for (vp = variables[hash(name)]; vp != NULL; vp = vp->v_link)
130		if (*vp->v_name == *name && equal(vp->v_name, name))
131			return (vp);
132	return (NULL);
133}
134
135/*
136 * Locate a group name and return it.
137 */
138
139struct grouphead *
140findgroup(char name[])
141{
142	struct grouphead *gh;
143
144	for (gh = groups[hash(name)]; gh != NULL; gh = gh->g_link)
145		if (*gh->g_name == *name && equal(gh->g_name, name))
146			return (gh);
147	return (NULL);
148}
149
150/*
151 * Print a group out on stdout
152 */
153void
154printgroup(char name[])
155{
156	struct grouphead *gh;
157	struct group *gp;
158
159	if ((gh = findgroup(name)) == NULL) {
160		printf("\"%s\": not a group\n", name);
161		return;
162	}
163	printf("%s\t", gh->g_name);
164	for (gp = gh->g_list; gp != NULL; gp = gp->ge_link)
165		printf(" %s", gp->ge_name);
166	printf("\n");
167}
168
169/*
170 * Hash the passed string and return an index into
171 * the variable or group hash table.
172 */
173int
174hash(const char *name)
175{
176	int h = 0;
177
178	while (*name != '\0') {
179		h <<= 2;
180		h += *name++;
181	}
182	if (h < 0 && (h = -h) < 0)
183		h = 0;
184	return (h % HSHSIZE);
185}
186