try {
      long remainingNanos = unit.toNanos(timeout);
      long end = System.nanoTime() + remainingNanos;

      while (true) {
        try {
          // CountDownLatch treats negative timeouts just like zero.
          return latch.await(remainingNanos, NANOSECONDS);
        } catch (InterruptedException e) {
          interrupted = true;
          remainingNanos = end - System.nanoTime();
        }

            } else {
              long remainingNanos;
              if (startTime == 0L) {
                startTime = initNanoTime(timeoutNanos);
                remainingNanos = timeoutNanos;
              } else {
                remainingNanos = remainingNanos(startTime, timeoutNanos);
              }
              satisfied = awaitNanos(guard, remainingNanos, signalBeforeWaiting);
            }