usr.bin/env/env.c

   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 }