git: 9front

ref: 2ce5f2b4ecfc37cbc032b5ea2102caa2de7bd6c6
dir: /sys/src/ape/lib/ap/amd64/lock.c/

View raw version 
#define _LOCK_EXTENSION
#include "../plan9/sys9.h"
#include <lock.h>

int	tas(int*);

void
lock(Lock *lk)
{
	while(tas(&lk->val))
		_SLEEP(0);
}

int
canlock(Lock *lk)
{
	if(tas(&lk->val))
		return 0;
	return 1;
}

void
unlock(Lock *lk)
{
	lk->val = 0;
}