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#include "pthread_impl.h"
struct cm {
pthread_cond_t *c;
pthread_mutex_t *m;
};
static void unwait(pthread_cond_t *c, pthread_mutex_t *m)
{
int w;
/* Cannot leave waiting status if there are any live broadcasters
* which might be inspecting/using the mutex. */
while ((w=c->_c_bcast)) __wait(&c->_c_bcast, &c->_c_leavers, w, 0);
/* If the waiter count is zero, it must be the case that the
* caller's count has been moved to the mutex due to bcast. */
do w = c->_c_waiters;
while (w && a_cas(&c->_c_waiters, w, w-1)!=w);
if (!w) a_dec(&m->_m_waiters);
}
static void cleanup(void *p)
{
struct cm *cm = p;
unwait(cm->c, cm->m);
pthread_mutex_lock(cm->m);
}
int pthread_cond_timedwait(pthread_cond_t *c, pthread_mutex_t *m, const struct timespec *ts)
{
struct cm cm = { .c=c, .m=m };
int r, e, tid;
if (ts && ts->tv_nsec >= 1000000000UL)
return EINVAL;
pthread_testcancel();
if (c->_c_mutex != (void *)-1) c->_c_mutex = m;
a_inc(&c->_c_waiters);
c->_c_block = tid = pthread_self()->tid;
if ((r=pthread_mutex_unlock(m))) return r;
do e = __timedwait(&c->_c_block, tid, c->_c_clock, ts, cleanup, &cm, 0);
while (c->_c_block == tid && (!e || e==EINTR));
if (e == EINTR) e = 0;
unwait(c, m);
if ((r=pthread_mutex_lock(m))) return r;
pthread_testcancel();
return e;
}
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