sync_unlock

# File lib/sync.rb, line 157
  def sync_unlock(m = EX)
    wakeup_threads = []
    @sync_mutex.synchronize do
      if sync_mode == UN
        Err::UnknownLocker.Fail(Thread.current)
      end
      
      m = sync_mode if m == EX and sync_mode == SH
      
      runnable = false
      case m
      when UN
        Err::UnknownLocker.Fail(Thread.current)
        
      when EX
        if sync_ex_locker == Thread.current
          if (self.sync_ex_count = sync_ex_count - 1) == 0
            self.sync_ex_locker = nil
            if sync_sh_locker.include?(Thread.current)
              self.sync_mode = SH
            else
              self.sync_mode = UN
            end
            runnable = true
          end
        else
          Err::UnknownLocker.Fail(Thread.current)
        end
        
      when SH
        if (count = sync_sh_locker[Thread.current]).nil?
          Err::UnknownLocker.Fail(Thread.current)
        else
          if (sync_sh_locker[Thread.current] = count - 1) == 0 
            sync_sh_locker.delete(Thread.current)
            if sync_sh_locker.empty? and sync_ex_count == 0
              self.sync_mode = UN
              runnable = true
            end
          end
        end
      end
      
      if runnable
        if sync_upgrade_waiting.size > 0
          th, count = sync_upgrade_waiting.shift
          sync_sh_locker[th] = count
          th.wakeup
          wakeup_threads.push th
        else
          wait = sync_waiting
          self.sync_waiting = []
          for th in wait
            th.wakeup
            wakeup_threads.push th
          end
        end
      end
    end
    for th in wakeup_threads
      th.run
    end
    self
  end