1 #if defined(LIBC_SCCS) && !defined(lint)
2 static const char sccsid[] = "@(#)setenv.c 8.1 (Berkeley) 6/4/93";
3 static const char rcsid[] = "$Id: setenv.c,v 1.1 2001/03/29 06:30:35 marka Exp $";
4 #endif /* LIBC_SCCS and not lint */
7 * Copyright (c) 1987, 1993
8 * The Regents of the University of California. All rights reserved.
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the University of
21 * California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 * may be used to endorse or promote products derived from this software
24 * without specific prior written permission.
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39 #include "port_before.h"
45 #include "port_after.h"
47 #if !defined(NEED_SETENV)
48 int __bindcompat_setenv;
51 extern char **environ;
53 static char *findenv(const char *name, int *offset);
57 * Set the value of the environmental variable "name" to be
58 * "value". If rewrite is set, replace any current value.
60 setenv(const char *name, const char *value, int rewrite) {
61 extern char **environ;
62 static int alloced; /* if allocated space before */
66 if (*value == '=') /* no `=' in value */
68 l_value = strlen(value);
69 if ((c = findenv(name, &offset))) { /* find if already exists */
72 if (strlen(c) >= l_value) { /* old larger; copy over */
73 while (*c++ = *value++);
76 } else { /* create new slot */
80 for (p = environ, cnt = 0; *p; ++p, ++cnt);
81 if (alloced) { /* just increase size */
82 environ = (char **)realloc((char *)environ,
83 (size_t)(sizeof(char *) * (cnt + 2)));
87 else { /* get new space */
88 alloced = 1; /* copy old entries into it */
89 p = malloc((size_t)(sizeof(char *) * (cnt + 2)));
92 memcpy(p, environ, cnt * sizeof(char *));
95 environ[cnt + 1] = NULL;
98 for (c = (char *)name; *c && *c != '='; ++c); /* no `=' in name */
99 if (!(environ[offset] = /* name + `=' + value */
100 malloc((size_t)((int)(c - name) + l_value + 2))))
102 for (c = environ[offset]; (*c = *name++) && *c != '='; ++c);
103 for (*c++ = '='; *c++ = *value++;);
109 * Delete environmental variable "name".
112 unsetenv(const char *name) {
116 while (findenv(name, &offset)) /* if set multiple times */
117 for (p = &environ[offset];; ++p)
118 if (!(*p = *(p + 1)))
124 * Returns pointer to value associated with name, if any, else NULL.
125 * Sets offset to be the offset of the name/value combination in the
126 * environmental array, for use by setenv(3) and unsetenv(3).
127 * Explicitly removes '=' in argument name.
129 * This routine *should* be a static; don't use it.
132 findenv(const char *name, int *offset) {
137 if (name == NULL || environ == NULL)
139 for (np = name; *np && *np != '='; ++np)
142 for (p = environ; (c = *p) != NULL; ++p)
143 if (strncmp(c, name, len) == 0 && c[len] == '=') {
144 *offset = p - environ;
145 return (c + len + 1);