1 /* $NetBSD: compat_unsetenv.c,v 1.4 2015/01/20 18:31:24 christos Exp $ */
2
3 /*
4 * Copyright (c) 1987, 1993
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 #include <sys/cdefs.h>
33 #if defined(LIBC_SCCS) && !defined(lint)
34 #if 0
35 static char sccsid[] = "from: @(#)setenv.c 8.1 (Berkeley) 6/4/93";
36 #else
37 __RCSID("$NetBSD: compat_unsetenv.c,v 1.4 2015/01/20 18:31:24 christos Exp $");
38 #endif
39 #endif /* LIBC_SCCS and not lint */
40
41 #define __LIBC12_SOURCE__
42 #include "namespace.h"
43
44 #include <assert.h>
45 #include <errno.h>
46 #include <stdlib.h>
47 #include <compat/include/stdlib.h>
48 #include <string.h>
49 #include <bitstring.h>
50 #include "local.h"
51
52 #ifdef __weak_alias
__weak_alias(unsetenv,_unsetenv)53 __weak_alias(unsetenv,_unsetenv)
54 #endif
55
56 #include "env.h"
57
58 __warn_references(unsetenv,
59 "warning: reference to compatibility unsetenv();"
60 " include <stdlib.h> for correct reference")
61
62 /*
63 * unsetenv(name) --
64 * Delete environmental variable "name".
65 */
66 void
67 unsetenv(const char *name)
68 {
69 size_t l_name;
70
71 _DIAGASSERT(name != NULL);
72
73 l_name = strlen(name);
74 if (__writelockenv()) {
75 ssize_t offset;
76
77 while ((offset = __getenvslot(name, l_name, false)) != -1) {
78 char **p;
79 for (p = &environ[offset]; ; ++p) {
80 if ((*p = *(p + 1)) == NULL)
81 break;
82 }
83 }
84 (void)__unlockenv();
85 }
86 }
87