kenv.c revision 309867 
1/*-
2 * Copyright (c) 2000  Peter Wemm <peter@freebsd.org>
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23 * SUCH DAMAGE.
24 */
25
26#include <sys/cdefs.h>
27__FBSDID("$FreeBSD: stable/10/bin/kenv/kenv.c 309867 2016-12-12 02:14:42Z delphij $");
28
29#include <sys/types.h>
30#include <sys/sysctl.h>
31#include <err.h>
32#include <kenv.h>
33#include <stdio.h>
34#include <stdlib.h>
35#include <string.h>
36#include <unistd.h>
37
38static void	usage(void);
39static int	kdumpenv(void);
40static int	kgetenv(const char *);
41static int	ksetenv(const char *, char *);
42static int	kunsetenv(const char *);
43
44static int hflag = 0;
45static int Nflag = 0;
46static int qflag = 0;
47static int uflag = 0;
48static int vflag = 0;
49
50static void
51usage(void)
52{
53	(void)fprintf(stderr, "%s\n%s\n%s\n",
54	    "usage: kenv [-hNq]",
55	    "       kenv [-qv] variable[=value]",
56	    "       kenv [-q] -u variable");
57	exit(1);
58}
59
60int
61main(int argc, char **argv)
62{
63	char *env, *eq, *val;
64	int ch, error;
65
66	val = NULL;
67	env = NULL;
68	while ((ch = getopt(argc, argv, "hNquv")) != -1) {
69		switch (ch) {
70		case 'h':
71			hflag++;
72			break;
73		case 'N':
74			Nflag++;
75			break;
76		case 'q':
77			qflag++;
78			break;
79		case 'u':
80			uflag++;
81			break;
82		case 'v':
83			vflag++;
84			break;
85		default:
86			usage();
87		}
88	}
89	argc -= optind;
90	argv += optind;
91	if (argc > 0) {
92		env = argv[0];
93		eq = strchr(env, '=');
94		if (eq != NULL) {
95			*eq++ = '\0';
96			val = eq;
97		}
98		argv++;
99		argc--;
100	}
101	if ((hflag || Nflag) && env != NULL)
102		usage();
103	if (argc > 0 || ((uflag || vflag) && env == NULL))
104		usage();
105	if (env == NULL) {
106		error = kdumpenv();
107		if (error && !qflag)
108			warn("kdumpenv");
109	} else if (val == NULL) {
110		if (uflag) {
111			error = kunsetenv(env);
112			if (error && !qflag)
113				warnx("unable to unset %s", env);
114		} else {
115			error = kgetenv(env);
116			if (error && !qflag)
117				warnx("unable to get %s", env);
118		}
119	} else {
120		error = ksetenv(env, val);
121		if (error && !qflag)
122			warnx("unable to set %s to %s", env, val);
123	}
124	return (error);
125}
126
127static int
128kdumpenv(void)
129{
130	char *buf, *bp, *cp;
131	int buflen, envlen;
132
133	envlen = kenv(KENV_DUMP, NULL, NULL, 0);
134	if (envlen < 0)
135		return (-1);
136	for (;;) {
137		buflen = envlen * 120 / 100;
138		buf = calloc(1, buflen + 1);
139		if (buf == NULL)
140			return (-1);
141		envlen = kenv(KENV_DUMP, NULL, buf, buflen);
142		if (envlen < 0) {
143			free(buf);
144			return (-1);
145		}
146		if (envlen > buflen)
147			free(buf);
148		else
149			break;
150	}
151
152	for (bp = buf; *bp != '\0'; bp += strlen(bp) + 1) {
153		if (hflag) {
154			if (strncmp(bp, "hint.", 5) != 0)
155				continue;
156		}
157		cp = strchr(bp, '=');
158		if (cp == NULL)
159			continue;
160		*cp++ = '\0';
161		if (Nflag)
162			printf("%s\n", bp);
163		else
164			printf("%s=\"%s\"\n", bp, cp);
165		bp = cp;
166	}
167
168	free(buf);
169	return (0);
170}
171
172static int
173kgetenv(const char *env)
174{
175	char buf[1024];
176	int ret;
177
178	ret = kenv(KENV_GET, env, buf, sizeof(buf));
179	if (ret == -1)
180		return (ret);
181	if (vflag)
182		printf("%s=\"%s\"\n", env, buf);
183	else
184		printf("%s\n", buf);
185	return (0);
186}
187
188static int
189ksetenv(const char *env, char *val)
190{
191	int ret;
192
193	ret = kenv(KENV_SET, env, val, strlen(val) + 1);
194	if (ret == 0)
195		printf("%s=\"%s\"\n", env, val);
196	return (ret);
197}
198
199static int
200kunsetenv(const char *env)
201{
202	int ret;
203
204	ret = kenv(KENV_UNSET, env, NULL, 0);
205	return (ret);
206}
207