xref: /freebsd/usr.bin/env/env.c (revision f3aff7c91bd451d300ffd37ddce5a1fdbe802123)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1988, 1993, 1994
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 #ifndef lint
33 static const char copyright[] =
34 "@(#) Copyright (c) 1988, 1993, 1994\n\
35 	The Regents of the University of California.  All rights reserved.\n";
36 #endif /* not lint */
37 
38 #if 0
39 #ifndef lint
40 static char sccsid[] = "@(#)env.c	8.3 (Berkeley) 4/2/94";
41 #endif /* not lint */
42 #endif
43 
44 #include <sys/cdefs.h>
45 __FBSDID("$FreeBSD$");
46 
47 #include <err.h>
48 #include <errno.h>
49 #include <stdio.h>
50 #include <string.h>
51 #include <stdlib.h>
52 #include <unistd.h>
53 
54 #include "envopts.h"
55 
56 extern char **environ;
57 
58 int	 env_verbosity;
59 
60 static void usage(void);
61 
62 int
63 main(int argc, char **argv)
64 {
65 	char *altpath, **ep, *p, **parg;
66 	char *cleanenv[1];
67 	int ch, want_clear;
68 	int rtrn;
69 
70 	altpath = NULL;
71 	want_clear = 0;
72 	while ((ch = getopt(argc, argv, "-iP:S:u:v")) != -1)
73 		switch(ch) {
74 		case '-':
75 		case 'i':
76 			want_clear = 1;
77 			break;
78 		case 'P':
79 			altpath = strdup(optarg);
80 			break;
81 		case 'S':
82 			/*
83 			 * The -S option, for "split string on spaces, with
84 			 * support for some simple substitutions"...
85 			 */
86 			split_spaces(optarg, &optind, &argc, &argv);
87 			break;
88 		case 'u':
89 			if (env_verbosity)
90 				fprintf(stderr, "#env unset:\t%s\n", optarg);
91 			rtrn = unsetenv(optarg);
92 			if (rtrn == -1)
93 				err(EXIT_FAILURE, "unsetenv %s", optarg);
94 			break;
95 		case 'v':
96 			env_verbosity++;
97 			if (env_verbosity > 1)
98 				fprintf(stderr, "#env verbosity now at %d\n",
99 				    env_verbosity);
100 			break;
101 		case '?':
102 		default:
103 			usage();
104 		}
105 	if (want_clear) {
106 		environ = cleanenv;
107 		cleanenv[0] = NULL;
108 		if (env_verbosity)
109 			fprintf(stderr, "#env clearing environ\n");
110 	}
111 	for (argv += optind; *argv && (p = strchr(*argv, '=')); ++argv) {
112 		if (env_verbosity)
113 			fprintf(stderr, "#env setenv:\t%s\n", *argv);
114 		*p = '\0';
115 		rtrn = setenv(*argv, p + 1, 1);
116 		*p = '=';
117 		if (rtrn == -1)
118 			err(EXIT_FAILURE, "setenv %s", *argv);
119 	}
120 	if (*argv) {
121 		if (altpath)
122 			search_paths(altpath, argv);
123 		if (env_verbosity) {
124 			fprintf(stderr, "#env executing:\t%s\n", *argv);
125 			for (parg = argv, argc = 0; *parg; parg++, argc++)
126 				fprintf(stderr, "#env    arg[%d]=\t'%s'\n",
127 				    argc, *parg);
128 			if (env_verbosity > 1)
129 				sleep(1);
130 		}
131 		execvp(*argv, argv);
132 		err(errno == ENOENT ? 127 : 126, "%s", *argv);
133 	}
134 	for (ep = environ; *ep; ep++)
135 		(void)printf("%s\n", *ep);
136 	exit(0);
137 }
138 
139 static void
140 usage(void)
141 {
142 	(void)fprintf(stderr,
143 	    "usage: env [-iv] [-P utilpath] [-S string] [-u name]\n"
144 	    "           [name=value ...] [utility [argument ...]]\n");
145 	exit(1);
146 }
147