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/* This file may have been modified by DJ Delorie (Jan 1991). If so,
** these modifications are Coyright (C) 1991 DJ Delorie, 24 Kirsten Ave,
** Rochester NH, 03867-2954, USA.
*/
/*
* Copyright (c) 1987 Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that: (1) source distributions retain this entire copyright
* notice and comment, and (2) distributions including binaries display
* the following acknowledgement: ``This product includes software
* developed by the University of California, Berkeley and its contributors''
* in the documentation or other materials provided with the distribution
* and in all advertising materials mentioning features or use of this
* software. 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 ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
/* _findenv is defined in getenv.c. */
extern char *_findenv _PARAMS ((const char *, int *));
/*
* setenv --
* Set the value of the environmental variable "name" to be
* "value". If rewrite is set, replace any current value.
*/
int
_DEFUN (setenv, (name, value, rewrite),
_CONST char *name _AND
_CONST char *value _AND
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 = (char **) malloc ((size_t) (sizeof (char *) * (cnt + 2)));
if (!P)
return (-1);
bcopy ((char *) environ, (char *) 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
_DEFUN (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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