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 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