nsz Git - musl/blob - src/thread/pthread_mutex_unlock.c

   1 #include "pthread_impl.h"
   2
   3 int pthread_mutex_unlock(pthread_mutex_t *m)
   4 {
   5         pthread_t self;
   6
   7         if (m->_m_type != PTHREAD_MUTEX_NORMAL) {
   8                 self = __pthread_self();
   9                 if ((m->_m_lock&0x1fffffff) != self->tid)
  10                         return EPERM;
  11                 if ((m->_m_type&3) == PTHREAD_MUTEX_RECURSIVE && --m->_m_count)
  12                         return 0;
  13                 if (m->_m_type >= 4) {
  14                         self->robust_list.pending = &m->_m_next;
  15                         *(void **)m->_m_prev = m->_m_next;
  16                         if (m->_m_next) ((void **)m->_m_next)[-1] = m->_m_prev;
  17                         a_store(&m->_m_lock, 0);
  18                         self->robust_list.pending = 0;
  19                 } else {
  20                         a_store(&m->_m_lock, 0);
  21                 }
  22         } else {
  23                 a_store(&m->_m_lock, 0);
  24         }
  25
  26         if (m->_m_waiters) __wake(&m->_m_lock, 1, 0);
  27         return 0;
  28 }