harvey/sys/src/libthread/xincport.h

/*
 * This file is part of the UCB release of Plan 9. It is subject to the license
 * terms in the LICENSE file found in the top-level directory of this
 * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No
 * part of the UCB release of Plan 9, including this file, may be copied,
 * modified, propagated, or distributed except according to the terms contained
 * in the LICENSE file.
 */

#include <u.h>
#include <libc.h>
#include <thread.h>

static Lock l;

void
_xinc(long *p)
{

	lock(&l);
	(*p)++;
	unlock(&l);
}

long
_xdec(long *p)
{
	long r;

	lock(&l);
	r = --(*p);
	unlock(&l);
	return r;
}