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#include "pthread_impl.h"
int __pthread_mutex_unlock(pthread_mutex_t *m)
{
pthread_t self;
int waiters = m->_m_waiters;
int cont;
int type = m->_m_type & 15;
int priv = (m->_m_type & 128) ^ 128;
int new = 0;
int old;
if (type != PTHREAD_MUTEX_NORMAL) {
self = __pthread_self();
old = m->_m_lock;
int own = old & 0x3fffffff;
if (own != self->tid)
return EPERM;
if ((type&3) == PTHREAD_MUTEX_RECURSIVE && m->_m_count)
return m->_m_count--, 0;
if ((type&4) && (old&0x40000000))
new = 0x7fffffff;
if (!priv) {
self->robust_list.pending = &m->_m_next;
__vm_lock();
}
volatile void *prev = m->_m_prev;
volatile void *next = m->_m_next;
*(volatile void *volatile *)prev = next;
if (next != &self->robust_list.head) *(volatile void *volatile *)
((char *)next - sizeof(void *)) = prev;
}
if (type&8) {
if (old<0 || a_cas(&m->_m_lock, old, new)!=old) {
if (new) a_store(&m->_m_waiters, -1);
__syscall(SYS_futex, &m->_m_lock, FUTEX_UNLOCK_PI|priv);
}
cont = 0;
waiters = 0;
} else {
cont = a_swap(&m->_m_lock, new);
}
if (type != PTHREAD_MUTEX_NORMAL && !priv) {
self->robust_list.pending = 0;
__vm_unlock();
}
if (waiters || cont<0)
__wake(&m->_m_lock, 1, priv);
return 0;
}
weak_alias(__pthread_mutex_unlock, pthread_mutex_unlock);
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