xref: /dragonfly/usr.bin/env/env.c (revision e5a92d33)
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  * @(#)env.c	8.3 (Berkeley) 4/2/94
32  * $FreeBSD: head/usr.bin/env/env.c 326025 2017-11-20 19:49:47Z pfg $
33  */
34 
35 #include <err.h>
36 #include <errno.h>
37 #include <stdio.h>
38 #include <string.h>
39 #include <stdlib.h>
40 #include <unistd.h>
41 
42 #include "envopts.h"
43 
44 extern char **environ;
45 
46 int	 env_verbosity;
47 
48 static void usage(void);
49 
50 int
51 main(int argc, char **argv)
52 {
53 	char *altpath, **ep, *p, **parg;
54 	char *cleanenv[1];
55 	int ch, want_clear;
56 	int rtrn;
57 
58 	altpath = NULL;
59 	want_clear = 0;
60 	while ((ch = getopt(argc, argv, "-iP:S:u:v")) != -1)
61 		switch(ch) {
62 		case '-':
63 		case 'i':
64 			want_clear = 1;
65 			break;
66 		case 'P':
67 			altpath = strdup(optarg);
68 			break;
69 		case 'S':
70 			/*
71 			 * The -S option, for "split string on spaces, with
72 			 * support for some simple substitutions"...
73 			 */
74 			split_spaces(optarg, &optind, &argc, &argv);
75 			break;
76 		case 'u':
77 			if (env_verbosity)
78 				fprintf(stderr, "#env unset:\t%s\n", optarg);
79 			rtrn = unsetenv(optarg);
80 			if (rtrn == -1)
81 				err(EXIT_FAILURE, "unsetenv %s", optarg);
82 			break;
83 		case 'v':
84 			env_verbosity++;
85 			if (env_verbosity > 1)
86 				fprintf(stderr, "#env verbosity now at %d\n",
87 				    env_verbosity);
88 			break;
89 		case '?':
90 		default:
91 			usage();
92 		}
93 	if (want_clear) {
94 		environ = cleanenv;
95 		cleanenv[0] = NULL;
96 		if (env_verbosity)
97 			fprintf(stderr, "#env clearing environ\n");
98 	}
99 	for (argv += optind; *argv && (p = strchr(*argv, '=')); ++argv) {
100 		if (env_verbosity)
101 			fprintf(stderr, "#env setenv:\t%s\n", *argv);
102 		*p = '\0';
103 		rtrn = setenv(*argv, p + 1, 1);
104 		*p = '=';
105 		if (rtrn == -1)
106 			err(EXIT_FAILURE, "setenv %s", *argv);
107 	}
108 	if (*argv) {
109 		if (altpath)
110 			search_paths(altpath, argv);
111 		if (env_verbosity) {
112 			fprintf(stderr, "#env executing:\t%s\n", *argv);
113 			for (parg = argv, argc = 0; *parg; parg++, argc++)
114 				fprintf(stderr, "#env    arg[%d]=\t'%s'\n",
115 				    argc, *parg);
116 			if (env_verbosity > 1)
117 				sleep(1);
118 		}
119 		execvp(*argv, argv);
120 		err(errno == ENOENT ? 127 : 126, "%s", *argv);
121 	}
122 	for (ep = environ; *ep; ep++)
123 		printf("%s\n", *ep);
124 	exit(0);
125 }
126 
127 static void
128 usage(void)
129 {
130 	fprintf(stderr,
131 	    "usage: env [-iv] [-P utilpath] [-S string] [-u name]\n"
132 	    "           [name=value ...] [utility [argument ...]]\n");
133 	exit(1);
134 }
135