/***********************************************************************
* *
* This software is part of the ast package *
* Copyright (c) 1985-2012 AT&T Intellectual Property *
* and is licensed under the *
* Eclipse Public License, Version 1.0 *
* by AT&T Intellectual Property *
* *
* A copy of the License is available at *
* http://www.eclipse.org/org/documents/epl-v10.html *
* (with md5 checksum b35adb5213ca9657e911e9befb180842) *
* *
* Information and Software Systems Research *
* AT&T Research *
* Florham Park NJ *
* *
* Glenn Fowler <gsf@research.att.com> *
* David Korn <dgk@research.att.com> *
* Phong Vo <kpv@research.att.com> *
* *
***********************************************************************/
#pragma prototyped
#include <aso.h>
int
asolock(unsigned int volatile* lock, unsigned int key, int type)
{
unsigned int k;
if (key)
switch (type)
{
case ASO_UNLOCK:
if (*lock != 0)
{
if (*lock != key)
return -1;
*lock = 0;
}
return 0;
case ASO_TRYLOCK:
if (*lock != key)
{
if (*lock != 0)
return -1;
*lock = key;
}
return 0;
case ASO_LOCK:
case ASO_SPINLOCK:
*lock = key;
return 0;
}
return -1;
}