1#include "pthread_impl.h"
 2#include <threads.h>
 3
 4int mtx_lock(mtx_t *m)
 5{
 6	if (m->_m_type == PTHREAD_MUTEX_NORMAL && !a_cas(&m->_m_lock, 0, EBUSY))
 7		return thrd_success;
 8	/* Calling mtx_timedlock with a null pointer is an extension.
 9	 * It is convenient, here to avoid duplication of the logic
10	 * for return values. */
11	return mtx_timedlock(m, 0);
12}