ref: a72a4c8b91dd7e0cd644963fe2a50fb07685e4d6
dir: /sys/src/ape/lib/ap/sparc/lock.c/
#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;
}