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#ifndef __LIBC_ATOMIC_H
#define __LIBC_ATOMIC_H
#include <libc/futex.h>
#include <sched.h>
#include <stdatomic.h>
#include <unistd.h>
#define LIBC_LOCK(__lock) __libc_lock(&((__lock)))
#define LIBC_UNLOCK(__lock) __libc_unlock(&((__lock)))
__attribute__((__always_inline__)) __inline void __libc_unlock(volatile atomic_flag *lock)
{
atomic_flag_clear_explicit(lock, memory_order_release);
__futex_wake((volatile int *)lock, 1);
}
__attribute__((__always_inline__)) __inline void __libc_lock(volatile atomic_flag *lock)
{
if (atomic_flag_test_and_set_explicit(lock, memory_order_acquire) == 0)
return;
while (1) {
__futex_wait((volatile int *)lock, 1);
if (atomic_flag_test_and_set_explicit(lock, memory_order_acquire) == 0)
return;
sched_yield();
}
}
#endif
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