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/*
* Copyright (c) 1987, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)setenv.c 8.1 (Berkeley) 6/4/93";
#endif /* LIBC_SCCS and not lint */
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
char *__findenv __P((const char *, int *));
/*
* setenv --
* Set the value of the environmental variable "name" to be
* "value". If rewrite is set, replace any current value.
*/
setenv(name, value, rewrite)
register const char *name;
register const char *value;
int rewrite;
{
extern char **environ;
static int alloced; /* if allocated space before */
register char *c;
int l_value, offset;
if (*value == '=') /* no `=' in value */
++value;
l_value = strlen(value);
if ((c = __findenv(name, &offset))) { /* find if already exists */
if (!rewrite)
return (0);
if (strlen(c) >= l_value) { /* old larger; copy over */
while (*c++ = *value++);
return (0);
}
} else { /* create new slot */
register int cnt;
register char **p;
for (p = environ, cnt = 0; *p; ++p, ++cnt);
if (alloced) { /* just increase size */
environ = (char **)realloc((char *)environ,
(size_t)(sizeof(char *) * (cnt + 2)));
if (!environ)
return (-1);
}
else { /* get new space */
alloced = 1; /* copy old entries into it */
p = malloc((size_t)(sizeof(char *) * (cnt + 2)));
if (!p)
return (-1);
bcopy(environ, p, cnt * sizeof(char *));
environ = p;
}
environ[cnt + 1] = NULL;
offset = cnt;
}
for (c = (char *)name; *c && *c != '='; ++c); /* no `=' in name */
if (!(environ[offset] = /* name + `=' + value */
malloc((size_t)((int)(c - name) + l_value + 2))))
return (-1);
for (c = environ[offset]; (*c = *name++) && *c != '='; ++c);
for (*c++ = '='; *c++ = *value++;);
return (0);
}
/*
* unsetenv(name) --
* Delete environmental variable "name".
*/
void
unsetenv(name)
const char *name;
{
extern char **environ;
register char **p;
int offset;
while (__findenv(name, &offset)) /* if set multiple times */
for (p = &environ[offset];; ++p)
if (!(*p = *(p + 1)))
break;
}
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