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/* This file may have been modified by DJ Delorie (Jan 1991). If so,
** these modifications are Copyright (C) 1991 DJ Delorie.
*/
/*
* 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 <reent.h>
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <errno.h>
#include "envlock.h"
extern char **environ;
/* Only deal with a pointer to environ, to work around subtle bugs with shared
libraries and/or small data systems where the user declares his own
'environ'. */
static char ***p_environ = &environ;
/* _findenv_r is defined in getenv_r.c. */
extern char *_findenv_r (struct _reent *, const char *, int *);
/*
* _setenv_r --
* Set the value of the environmental variable "name" to be
* "value". If rewrite is set, replace any current value.
* If "name" contains equal sign, -1 is returned, and errno is
* set to EINVAL;
*/
int
_setenv_r (struct _reent *reent_ptr,
const char *name,
const char *value,
int rewrite)
{
static int alloced; /* if allocated space before */
register char *C;
int l_value, offset;
if (strchr(name, '='))
{
errno = EINVAL;
return -1;
}
ENV_LOCK;
l_value = strlen (value);
if ((C = _findenv_r (reent_ptr, name, &offset)))
{ /* find if already exists */
if (!rewrite)
{
ENV_UNLOCK;
return 0;
}
if (strlen (C) >= l_value)
{ /* old larger; copy over */
while ((*C++ = *value++) != 0);
ENV_UNLOCK;
return 0;
}
}
else
{ /* create new slot */
register int cnt;
register char **P;
for (P = *p_environ, cnt = 0; *P; ++P, ++cnt);
if (alloced)
{ /* just increase size */
*p_environ = (char **) _realloc_r (reent_ptr, (char *) environ,
(size_t) (sizeof (char *) * (cnt + 2)));
if (!*p_environ)
{
ENV_UNLOCK;
return -1;
}
}
else
{ /* get new space */
alloced = 1; /* copy old entries into it */
P = (char **) _malloc_r (reent_ptr, (size_t) (sizeof (char *) * (cnt + 2)));
if (!P)
{
ENV_UNLOCK;
return (-1);
}
memcpy((char *) P,(char *) *p_environ, cnt * sizeof (char *));
*p_environ = P;
}
(*p_environ)[cnt + 1] = NULL;
offset = cnt;
}
for (C = (char *) name; *C && *C != '='; ++C); /* no `=' in name */
if (!((*p_environ)[offset] = /* name + `=' + value */
_malloc_r (reent_ptr, (size_t) ((int) (C - name) + l_value + 2))))
{
ENV_UNLOCK;
return -1;
}
for (C = (*p_environ)[offset]; (*C = *name++) && *C != '='; ++C);
for (*C++ = '='; (*C++ = *value++) != 0;);
ENV_UNLOCK;
return 0;
}
/*
* _unsetenv_r(name) --
* Delete environmental variable "name".
*/
int
_unsetenv_r (struct _reent *reent_ptr,
const char *name)
{
register char **P;
int offset;
/* Name cannot be NULL, empty, or contain an equal sign. */
if (name == NULL || name[0] == '\0' || strchr(name, '='))
{
errno = EINVAL;
return -1;
}
ENV_LOCK;
while (_findenv_r (reent_ptr, name, &offset)) /* if set multiple times */
{
for (P = &(*p_environ)[offset];; ++P)
if (!(*P = *(P + 1)))
break;
}
ENV_UNLOCK;
return 0;
}
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