mirror of
https://github.com/autc04/Retro68.git
synced 2024-11-30 19:53:46 +00:00
136 lines
3.7 KiB
C
136 lines
3.7 KiB
C
/*
|
|
FUNCTION
|
|
<<_getenv_r>>---look up environment variable
|
|
|
|
INDEX
|
|
_getenv_r
|
|
INDEX
|
|
environ
|
|
|
|
ANSI_SYNOPSIS
|
|
#include <stdlib.h>
|
|
char *_getenv_r(struct _reent *<[reent_ptr]>, const char *<[name]>);
|
|
|
|
TRAD_SYNOPSIS
|
|
#include <stdlib.h>
|
|
char *_getenv_r(<[reent_ptr]>, <[name]>)
|
|
struct _reent *<[reent_ptr]>;
|
|
char *<[name]>;
|
|
|
|
DESCRIPTION
|
|
<<_getenv_r>> searches the list of environment variable names and values
|
|
(using the global pointer ``<<char **environ>>'') for a variable whose
|
|
name matches the string at <[name]>. If a variable name matches,
|
|
<<_getenv_r>> returns a pointer to the associated value.
|
|
|
|
RETURNS
|
|
A pointer to the (string) value of the environment variable, or
|
|
<<NULL>> if there is no such environment variable.
|
|
|
|
PORTABILITY
|
|
<<_getenv_r>> is not ANSI; the rules for properly forming names of environment
|
|
variables vary from one system to another. This implementation does not
|
|
permit '=' to be in identifiers.
|
|
|
|
<<_getenv_r>> requires a global pointer <<environ>>.
|
|
*/
|
|
|
|
/* 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 <stdlib.h>
|
|
#include <stddef.h>
|
|
#include <string.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 --
|
|
* Returns pointer to value associated with name, if any, else NULL.
|
|
* Sets offset to be the offset of the name/value combination in the
|
|
* environmental array, for use by setenv(3) and unsetenv(3).
|
|
*
|
|
* This routine *should* be a static; don't use it.
|
|
*/
|
|
|
|
char *
|
|
_DEFUN (_findenv_r, (reent_ptr, name, offset),
|
|
struct _reent *reent_ptr _AND
|
|
register _CONST char *name _AND
|
|
int *offset)
|
|
{
|
|
register int len;
|
|
register char **p;
|
|
_CONST char *c;
|
|
|
|
ENV_LOCK;
|
|
|
|
/* In some embedded systems, this does not get set. This protects
|
|
newlib from dereferencing a bad pointer. */
|
|
if (!*p_environ)
|
|
{
|
|
ENV_UNLOCK;
|
|
return NULL;
|
|
}
|
|
|
|
c = name;
|
|
while (*c && *c != '=') c++;
|
|
|
|
/* Identifiers may not contain an '=', so cannot match if does */
|
|
if(*c != '=')
|
|
{
|
|
len = c - name;
|
|
for (p = *p_environ; *p; ++p)
|
|
if (!strncmp (*p, name, len))
|
|
if (*(c = *p + len) == '=')
|
|
{
|
|
*offset = p - *p_environ;
|
|
ENV_UNLOCK;
|
|
return (char *) (++c);
|
|
}
|
|
}
|
|
ENV_UNLOCK;
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* _getenv_r --
|
|
* Returns ptr to value associated with name, if any, else NULL.
|
|
*/
|
|
|
|
char *
|
|
_DEFUN (_getenv_r, (reent_ptr, name),
|
|
struct _reent *reent_ptr _AND
|
|
_CONST char *name)
|
|
{
|
|
int offset;
|
|
|
|
return _findenv_r (reent_ptr, name, &offset);
|
|
}
|