1/* 2 * Copyright (c) 1987, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34#include "config.h" 35 36#if defined(LIBC_SCCS) && !defined(lint) 37static const char sccsid[] = "@(#)getenv.c 8.1 (Berkeley) 6/4/93"; 38static const char sccsid[] = "@(#)setenv.c 8.1 (Berkeley) 6/4/93"; 39#endif /* LIBC_SCCS and not lint */ 40#else 41__RCSID("$NetBSD$"); 42#endif 43 44#include <stdlib.h> 45#include <string.h> 46 47/* 48 * __findenv -- 49 * Returns pointer to value associated with name, if any, else NULL. 50 * Sets offset to be the offset of the name/value combination in the 51 * environmental array, for use by setenv(3) and unsetenv(3). 52 * Explicitly removes '=' in argument name. 53 * 54 * This routine *should* be a static; don't use it. 55 */ 56static char * 57__findenv(register char *name, int *offset) 58{ 59 extern char **environ; 60 register int len; 61 register char *np; 62 register char **p, *c; 63 64 if (name == NULL || environ == NULL) 65 return (NULL); 66 for (np = name; *np && *np != '='; ++np) 67 continue; 68 len = np - name; 69 for (p = environ; (c = *p) != NULL; ++p) 70 if (strncmp(c, name, len) == 0 && c[len] == '=') { 71 *offset = p - environ; 72 return (c + len + 1); 73 } 74 return (NULL); 75} 76 77#ifndef HAVE_SETENV 78/* 79 * setenv -- 80 * Set the value of the environmental variable "name" to be 81 * "value". If rewrite is set, replace any current value. 82 * 83 * PUBLIC: #ifndef HAVE_SETENV 84 * PUBLIC: int setenv __P((const char *, const char *, int)); 85 * PUBLIC: #endif 86 */ 87setenv(name, value, rewrite) 88 register char *name; 89 register char *value; 90 int rewrite; 91{ 92 extern char **environ; 93 static int alloced; /* if allocated space before */ 94 register char *c; 95 int l_value, offset; 96 97 if (*value == '=') /* no `=' in value */ 98 ++value; 99 l_value = strlen(value); 100 if ((c = __findenv(name, &offset))) { /* find if already exists */ 101 if (!rewrite) 102 return (0); 103 if (strlen(c) >= l_value) { /* old larger; copy over */ 104 while (*c++ = *value++); 105 return (0); 106 } 107 } else { /* create new slot */ 108 register int cnt; 109 register char **p; 110 111 for (p = environ, cnt = 0; *p; ++p, ++cnt); 112 if (alloced) { /* just increase size */ 113 environ = (char **)realloc((char *)environ, 114 (size_t)(sizeof(char *) * (cnt + 2))); 115 if (!environ) 116 return (-1); 117 } 118 else { /* get new space */ 119 alloced = 1; /* copy old entries into it */ 120 p = malloc((size_t)(sizeof(char *) * (cnt + 2))); 121 if (!p) 122 return (-1); 123 memmove(p, environ, cnt * sizeof(char *)); 124 environ = p; 125 } 126 environ[cnt + 1] = NULL; 127 offset = cnt; 128 } 129 for (c = (char *)name; *c && *c != '='; ++c); /* no `=' in name */ 130 if (!(environ[offset] = /* name + `=' + value */ 131 malloc((size_t)((int)(c - name) + l_value + 2)))) 132 return (-1); 133 for (c = environ[offset]; (*c = *name++) && *c != '='; ++c); 134 for (*c++ = '='; *c++ = *value++;); 135 return (0); 136} 137#endif 138 139#ifndef HAVE_UNSETENV 140/* 141 * unsetenv(name) -- 142 * Delete environmental variable "name". 143 * 144 * PUBLIC: #ifndef HAVE_UNSETENV 145 * PUBLIC: void unsetenv __P((const char *)); 146 * PUBLIC: #endif 147 */ 148void 149unsetenv(name) 150 char *name; 151{ 152 extern char **environ; 153 register char **p; 154 int offset; 155 156 while (__findenv(name, &offset)) /* if set multiple times */ 157 for (p = &environ[offset];; ++p) 158 if (!(*p = *(p + 1))) 159 break; 160} 161#endif 162