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/* Copyright (C) 1992, 1995 Free Software Foundation, Inc.
This file is part of the GNU C Library. */
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
extern char ** environ;
int
setenv(name, value, replace)
__const char *name;
__const char *value;
int replace;
{
register char **ep;
register size_t size;
__const size_t namelen = strlen (name);
__const size_t vallen = strlen (value);
int result = 0;
size = 0;
for (ep = environ; *ep != NULL; ++ep)
if (!memcmp (*ep, name, namelen) && (*ep)[namelen] == '=')
break;
else
++size;
if (*ep == NULL)
{
static char **last_environ = NULL;
char **new_environ = (char **) malloc((size + 2) * sizeof(char *));
if (new_environ == NULL)
{
result = -1;
goto do_return;
}
(void) memcpy((void*) new_environ, (void*) environ, size * sizeof(char *));
new_environ[size] = malloc (namelen + 1 + vallen + 1);
if (new_environ[size] == NULL)
{
free (new_environ);
errno = ENOMEM;
result = -1;
goto do_return;
}
memcpy (new_environ[size], name, namelen);
new_environ[size][namelen] = '=';
memcpy (&new_environ[size][namelen + 1], value, vallen + 1);
new_environ[size + 1] = NULL;
if (last_environ != NULL)
free ((void*) last_environ);
last_environ = new_environ;
environ = new_environ;
}
else if (replace)
{
size_t len = strlen (*ep);
if (len < namelen + 1 + vallen)
{
char *new = malloc (namelen + 1 + vallen + 1);
if (new == NULL)
{
result = -1;
goto do_return;
}
*ep = new;
}
memcpy (*ep, name, namelen);
(*ep)[namelen] = '=';
memcpy (&(*ep)[namelen + 1], value, vallen + 1);
}
do_return:
return result;
}
void
unsetenv(name)
__const char *name;
{
register char **ep;
register char **dp;
__const size_t namelen = strlen (name);
for (dp = ep = environ; *ep != NULL; ++ep)
if (memcmp (*ep, name, namelen) || (*ep)[namelen] != '=')
{
*dp = *ep;
++dp;
}
*dp = NULL;
}
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