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/* See LICENSE file for copyright and license details. */
#include <linux/futex.h>
#include <sys/syscall.h>
#include "internal-llmutex.h"
typedef volatile _Atomic uint32_t MUTEX;
_Static_assert(sizeof(MUTEX) == sizeof(uint32_t));
#define INIT_MUTEX(MUTEX)\
atomic_init(&(MUTEX), 0)
#define _TRYLOCK(MUTEX)\
!atomic_exchange(&(MUTEX), 1)
#define _LOCK(MUTEX)\
do {\
while (!_TRYLOCK(MUTEX))\
_WAIT(MUTEX);\
} while (0)
#define _UNLOCK(MUTEX)\
do {\
atomic_store(&(MUTEX), 0);\
if (syscall(SYS_futex, &(MUTEX), FUTEX_PRIVATE_FLAG | FUTEX_WAKE, INT_MAX, NULL, 0, 0) < 0) {\
/* XXX handle of error in _UNLOCK */\
abort();\
}\
} while (0)
#define _WAIT(MUTEX)\
do {\
if (syscall(SYS_futex, &(MUTEX), FUTEX_PRIVATE_FLAG | FUTEX_WAIT, 1, NULL, 0, 0) < 0) {\
/* XXX handle of error in _WAIT */\
abort();\
}\
} while (0)
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