git: 9front

ref: c966ea5e449c2e59b01b7b0499b1bffba633d7dd
dir: /sys/src/ape/lib/ap/sparc/lock.c/

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#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;
}