poll_timeout_kipclock

// vi:set ft=cpp: -*- Mode: C++ -*-
/*
 * (c) 2012 Adam Lackorzynski <adam@os.inf.tu-dresden.de>,
 *     economic rights: Technische Universität Dresden (Germany)
 * This file is part of TUD:OS and distributed under the terms of the
 * GNU Lesser General Public License 2.1.
 * Please see the COPYING-LGPL-2.1 file for details.
 */
#pragma once
 
#include <cassert>
#include <l4/sys/kip.h>
#include <l4/re/env.h>
 
namespace L4 {
 
class Poll_timeout_kipclock
{
public:
  Poll_timeout_kipclock(unsigned poll_time_us)
  {
    set(poll_time_us);
  }
 
  void set(unsigned poll_time_us)
  {
    _timeout = l4_kip_clock(l4re_kip()) + poll_time_us;
    _last_check = true;
  }
 
  bool test(bool expression = true)
  {
    if (!expression)
      return false;
 
    return _last_check = l4_kip_clock(l4re_kip()) < _timeout;
  }
 
  bool timed_out() const { return !_last_check; }
 
private:
  l4_cpu_time_t _timeout;
  bool _last_check;
};
}