LXR busybox/coreutils/env.c

   1/* vi: set sw=4 ts=4: */
   2/*
   3 * env implementation for busybox
   4 *
   5 * Copyright (c) 1988, 1993, 1994
   6 * The Regents of the University of California.  All rights reserved.
   7 *
   8 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   9 *
  10 * Original copyright notice is retained at the end of this file.
  11 *
  12 * Modified for BusyBox by Erik Andersen <andersen@codepoet.org>
  13 */
  14/* Mar 16, 2003      Manuel Novoa III   (mjn3@codepoet.org)
  15 *
  16 * Fixed bug involving exit return codes if execvp fails.  Also added
  17 * output error checking.
  18 */
  19/*
  20 * Modified by Vladimir Oleynik <dzo@simtreas.ru> (C) 2003
  21 * - correct "-" option usage
  22 * - multiple "-u unsetenv" support
  23 * - GNU long option support
  24 * - use xfunc_error_retval
  25 */
  26//config:config ENV
  27//config:       bool "env (4 kb)"
  28//config:       default y
  29//config:       help
  30//config:       env is used to set an environment variable and run
  31//config:       a command; without options it displays the current
  32//config:       environment.
  33
  34//applet:IF_ENV(APPLET_NOEXEC(env, env, BB_DIR_USR_BIN, BB_SUID_DROP, env))
  35
  36//kbuild:lib-$(CONFIG_ENV) += env.o
  37
  38/* BB_AUDIT SUSv3 compliant */
  39/* http://www.opengroup.org/onlinepubs/007904975/utilities/env.html */
  40
  41//usage:#define env_trivial_usage
  42//usage:       "[-iu] [-] [name=value]... [PROG ARGS]"
  43//usage:#define env_full_usage "\n\n"
  44//usage:       "Print the current environment or run PROG after setting up\n"
  45//usage:       "the specified environment\n"
  46//usage:     "\n        -, -i   Start with an empty environment"
  47//usage:     "\n        -u      Remove variable from the environment"
  48
  49#include "libbb.h"
  50
  51int env_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  52int env_main(int argc UNUSED_PARAM, char **argv)
  53{
  54        unsigned opts;
  55        llist_t *unset_env = NULL;
  56
  57        opts = getopt32long(argv, "+iu:*",
  58                        "ignore-environment\0" No_argument       "i"
  59                        "unset\0"              Required_argument "u"
  60                        , &unset_env
  61        );
  62        argv += optind;
  63        if (argv[0] && LONE_DASH(argv[0])) {
  64                opts |= 1;
  65                ++argv;
  66        }
  67        if (opts & 1) {
  68                clearenv();
  69        }
  70        while (unset_env) {
  71                char *var = llist_pop(&unset_env);
  72                /* This does not handle -uVAR=VAL
  73                 * (coreutils _sets_ the variable in that case): */
  74                /*unsetenv(var);*/
  75                /* This does, but uses somewhan undocumented feature that
  76                 * putenv("name_without_equal_sign") unsets the variable: */
  77                putenv(var);
  78        }
  79
  80        while (*argv && (strchr(*argv, '=') != NULL)) {
  81                if (putenv(*argv) < 0) {
  82                        bb_perror_msg_and_die("putenv");
  83                }
  84                ++argv;
  85        }
  86
  87        if (argv[0]) {
  88                BB_EXECVP_or_die(argv);
  89        }
  90
  91        if (environ) { /* clearenv() may set environ == NULL! */
  92                char **ep;
  93                for (ep = environ; *ep; ep++) {
  94                        puts(*ep);
  95                }
  96        }
  97
  98        fflush_stdout_and_exit(EXIT_SUCCESS);
  99}
 100
 101/*
 102 * Copyright (c) 1988, 1993, 1994
 103 *      The Regents of the University of California.  All rights reserved.
 104 *
 105 * Redistribution and use in source and binary forms, with or without
 106 * modification, are permitted provided that the following conditions
 107 * are met:
 108 * 1. Redistributions of source code must retain the above copyright
 109 *    notice, this list of conditions and the following disclaimer.
 110 * 2. Redistributions in binary form must reproduce the above copyright
 111 *    notice, this list of conditions and the following disclaimer in the
 112 *    documentation and/or other materials provided with the distribution.
 113 *
 114 * 3. BSD Advertising Clause omitted per the July 22, 1999 licensing change
 115 *    ftp://ftp.cs.berkeley.edu/pub/4bsd/README.Impt.License.Change
 116 *
 117 * 4. Neither the name of the University nor the names of its contributors
 118 *    may be used to endorse or promote products derived from this software
 119 *    without specific prior written permission.
 120 *
 121 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ''AS IS'' AND
 122 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 123 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 124 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 125 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 126 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 127 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 128 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 129 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 130 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 131 * SUCH DAMAGE.
 132 */
 133