newlib-cygwin/newlib/libc/stdio/fsetlocking.c

90 lines
2.7 KiB
C

/*
* Copyright (c) 2014 Red Hat, Inc.
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*/
/*
FUNCTION
<<__fsetlocking>>---set or query locking mode on FILE stream
INDEX
__fsetlocking
SYNOPSIS
#include <stdio.h>
#include <stdio_ext.h>
int __fsetlocking(FILE *<[fp]>, int <[type]>);
DESCRIPTION
This function sets how the stdio functions handle locking of FILE <[fp]>.
The following values describe <[type]>:
<<FSETLOCKING_INTERNAL>> is the default state, where stdio functions
automatically lock and unlock the stream.
<<FSETLOCKING_BYCALLER>> means that automatic locking in stdio functions
is disabled. Applications which set this take all responsibility for file
locking themselves.
<<FSETLOCKING_QUERY>> returns the current locking mode without changing it.
RETURNS
<<__fsetlocking>> returns the current locking mode of <[fp]>.
PORTABILITY
This function originates from Solaris and is also provided by GNU libc.
No supporting OS subroutines are required.
*/
#ifndef __rtems__
#include <_ansi.h>
#include <stdio.h>
#include <stdio_ext.h>
#include "local.h"
int
__fsetlocking (FILE * fp,
int type)
{
int result;
CHECK_INIT(_REENT, fp);
result = (fp->_flags2 & __SNLK) ? FSETLOCKING_BYCALLER : FSETLOCKING_INTERNAL;
switch (type)
{
case FSETLOCKING_BYCALLER:
fp->_flags2 |= __SNLK;
break;
case FSETLOCKING_INTERNAL:
fp->_flags2 &= ~__SNLK;
break;
case FSETLOCKING_QUERY:
default:
break;
}
return result;
}
#endif /* __rtems__ */