# File monitor.rb, line 165
    def initialize(monitor)
      @monitor = monitor
      @waiters = []
    end

# File monitor.rb, line 148
    def broadcast
      @monitor.instance_eval {mon_check_owner()}
      Thread.critical = true
      for t in @waiters
        t.wakeup
      end
      @waiters.clear
      Thread.critical = false
      Thread.pass
    end

# File monitor.rb, line 159
    def count_waiters
      return @waiters.length
    end

# File monitor.rb, line 138
    def signal
      @monitor.instance_eval {mon_check_owner()}
      Thread.critical = true
      t = @waiters.shift
      t.wakeup if t
      Thread.critical = false
      Thread.pass
    end

# File monitor.rb, line 93
    def wait(timeout = nil)
      @monitor.instance_eval {mon_check_owner()}
      timer = create_timer(timeout)
      
      Thread.critical = true
      count = @monitor.instance_eval {mon_exit_for_cond()}
      @waiters.push(Thread.current)

      begin
        Thread.stop
        return true
      rescue Timeout
        return false
      ensure
        Thread.critical = true
        begin
          if timer && timer.alive?
            Thread.kill(timer)
          end
          if @waiters.include?(Thread.current)  # interrupted?
            @waiters.delete(Thread.current)
          end
          @monitor.instance_eval {mon_enter_for_cond(count)}
        ensure
          Thread.critical = false
        end
      end
    end

# File monitor.rb, line 131
    def wait_until
      until yield
        wait
      end
    end

# File monitor.rb, line 124
    def wait_while
      while yield
        wait
      end
    end