text: //
  // detail/timer_queue_base.hpp
  // ~~~~~~~~~~~~~~~~~~~~~~~~~~~
  //
  // Copyright (c) 2003-2011 Christopher M. Kohlhoff (chris at kohlhoff dot com)
  //
  // Distributed under the Boost Software License, Version 1.0. (See accompanying
  // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
  //
  
  #ifndef BOOST_ASIO_DETAIL_TIMER_QUEUE_BASE_HPP
  #define BOOST_ASIO_DETAIL_TIMER_QUEUE_BASE_HPP
  
  #if defined(_MSC_VER) && (_MSC_VER >= 1200)
  # pragma once
  #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
  
  #include <boost/asio/detail/config.hpp>
  #include <boost/asio/detail/noncopyable.hpp>
  #include <boost/asio/detail/op_queue.hpp>
  #include <boost/asio/detail/operation.hpp>
  
  #include <boost/asio/detail/push_options.hpp>
  
  namespace boost {
  namespace asio {
  namespace detail {
  
  class timer_queue_base
    : private noncopyable
  {
  public:
    // Constructor.
    timer_queue_base() : next_(0) {}
  
    // Destructor.
    virtual ~timer_queue_base() {}
  
    // Whether there are no timers in the queue.
    virtual bool empty() const = 0;
  
    // Get the time to wait until the next timer.
    virtual long wait_duration_msec(long max_duration) const = 0;
  
    // Get the time to wait until the next timer.
    virtual long wait_duration_usec(long max_duration) const = 0;
  
    // Dequeue all ready timers.
    virtual void get_ready_timers(op_queue<operation>& ops) = 0;
  
    // Dequeue all timers.
    virtual void get_all_timers(op_queue<operation>& ops) = 0;
  
  private:
    friend class timer_queue_set;
  
    // Next timer queue in the set.
    timer_queue_base* next_;
  };
  
  } // namespace detail
  } // namespace asio
  } // namespace boost
  
  #include <boost/asio/detail/pop_options.hpp>
  
  #endif // BOOST_ASIO_DETAIL_TIMER_QUEUE_BASE_HPP
  