text: #include "pthread_impl.h"
  
  int __pthread_mutex_timedlock(pthread_mutex_t *restrict m, const struct timespec *restrict at)
  {
  	if ((m->_m_type&15) == PTHREAD_MUTEX_NORMAL
  	    && !a_cas(&m->_m_lock, 0, EBUSY))
  		return 0;
  
  	int type = m->_m_type;
  	int r, t, priv = (type & 128) ^ 128;
  
  	r = __pthread_mutex_trylock(m);
  	if (r != EBUSY) return r;
  	
  	int spins = 100;
  	while (spins-- && m->_m_lock && !m->_m_waiters) a_spin();
  
  	while ((r=__pthread_mutex_trylock(m)) == EBUSY) {
  		r = m->_m_lock;
  		int own = r & 0x3fffffff;
  		if (!own && (!r || (type&4)))
  			continue;
  		if ((type&3) == PTHREAD_MUTEX_ERRORCHECK
  		    && own == __pthread_self()->tid)
  			return EDEADLK;
  
  		a_inc(&m->_m_waiters);
  		t = r | 0x80000000;
  		a_cas(&m->_m_lock, r, t);
  		r = __timedwait(&m->_m_lock, t, CLOCK_REALTIME, at, priv);
  		a_dec(&m->_m_waiters);
  		if (r && r != EINTR) break;
  	}
  	return r;
  }
  
  weak_alias(__pthread_mutex_timedlock, pthread_mutex_timedlock);
  