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                 if (!m->_m_lock)
   9                         return EPERM;
  10                 self = __pthread_self();
  11                 if ((m->_m_lock&0x1fffffff) != self->tid)
  12                         return EPERM;
  13                 if ((m->_m_type&3) == PTHREAD_MUTEX_RECURSIVE && --m->_m_count)
  14                         return 0;
  15                 if (m->_m_type >= 4) {
  16                         self->robust_list.pending = &m->_m_next;
  17                         *(void **)m->_m_prev = m->_m_next;
  18                         if (m->_m_next) ((void **)m->_m_next)[-1] = m->_m_prev;
  19                         a_store(&m->_m_lock, 0);
  20                         self->robust_list.pending = 0;
  21                 } else {
  22                         a_store(&m->_m_lock, 0);
  23                 }
  24         } else {
  25                 a_store(&m->_m_lock, 0);
  26         }
  27
  28         if (m->_m_waiters) __wake(&m->_m_lock, 1, 0);
  29         return 0;
  30 }