1#ifndef LOCK_H
 2#define LOCK_H
 3
 4#if defined(__wasilibc_unmodified_upstream) || defined(_REENTRANT)
 5hidden void __lock(volatile int *);
 6hidden void __unlock(volatile int *);
 7#define LOCK(x) __lock(x)
 8#define UNLOCK(x) __unlock(x)
 9#else
10// No locking needed.
11#define LOCK(x) ((void)0)
12#define UNLOCK(x) ((void)0)
13#endif
14
15#endif