1/*	$NetBSD: env.c,v 1.23 2020/02/08 11:02:07 kamil Exp $	*/
2/*
3 * Copyright (c) 1988, 1993, 1994
4 *	The Regents of the University of California.  All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. Neither the name of the University nor the names of its contributors
15 *    may be used to endorse or promote products derived from this software
16 *    without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31#include <sys/cdefs.h>
32#ifndef lint
33__COPYRIGHT("@(#) Copyright (c) 1988, 1993, 1994\
34 The Regents of the University of California.  All rights reserved.");
35#endif /* not lint */
36
37#ifndef lint
38/*static char sccsid[] = "@(#)env.c	8.3 (Berkeley) 4/2/94";*/
39__RCSID("$NetBSD: env.c,v 1.23 2020/02/08 11:02:07 kamil Exp $");
40#endif /* not lint */
41
42#include <err.h>
43#include <stdio.h>
44#include <string.h>
45#include <stdlib.h>
46#include <unistd.h>
47#include <locale.h>
48#include <errno.h>
49
50static void usage(void) __dead;
51
52extern char **environ;
53
54int
55main(int argc, char **argv)
56{
57	char **ep, term;
58	char *cleanenv[1];
59	int ch;
60
61	setprogname(*argv);
62	(void)setlocale(LC_ALL, "");
63
64	term = '\n';
65	while ((ch = getopt(argc, argv, "-0iu:")) != -1)
66		switch((char)ch) {
67		case '0':
68			term = '\0';
69			break;
70		case '-':			/* obsolete */
71		case 'i':
72			environ = cleanenv;
73			cleanenv[0] = NULL;
74			break;
75		case 'u':
76			if (unsetenv(optarg) == -1)
77				errx(EXIT_FAILURE, "unsetenv %s", optarg);
78			break;
79		case '?':
80		default:
81			usage();
82		}
83
84	for (argv += optind; *argv && strchr(*argv, '=') != NULL; ++argv)
85		(void)putenv(*argv);
86
87	if (*argv) {
88		/* return 127 if the command to be run could not be found; 126
89		   if the command was found but could not be invoked; 125 if
90		   -0 was specified with utility.*/
91
92		if (term == '\0')
93			errx(125, "cannot specify command with -0");
94
95		(void)execvp(*argv, argv);
96		err((errno == ENOENT) ? 127 : 126, "%s", *argv);
97		/* NOTREACHED */
98	}
99
100	for (ep = environ; *ep; ep++)
101		(void)printf("%s%c", *ep, term);
102
103	exit(0);
104}
105
106static void
107usage(void)
108{
109	(void)fprintf(stderr,
110	    "Usage: %s [-0i] [-u name] [name=value ...] [command]\n",
111	    getprogname());
112	exit(1);
113}
114