ceph/src/boost/libs/chrono/example/timer.hpp

   1 //  boost/chrono/timer.hpp  ------------------------------------------------------------//
   2
   3 //  Copyright Beman Dawes 2008
   4 //  Copyright 2009 Vicente J. Botet Escriba
   5
   6 //  Distributed under the Boost Software License, Version 1.0. (See accompanying
   7 //  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   8
   9 //  See http://www.boost.org/libs/system for documentation.
  10
  11 #ifndef BOOSTEX_CHRONO_TIMER_HPP
  12 #define BOOSTEX_CHRONO_TIMER_HPP
  13
  14 #include <boost/chrono/chrono.hpp>
  15 #include <boost/system/error_code.hpp>
  16
  17 namespace boost_ex
  18 {
  19   namespace chrono
  20   {
  21
  22 //--------------------------------------------------------------------------------------//
  23 //                                    timer                                             //
  24 //--------------------------------------------------------------------------------------//
  25
  26     template <class Clock=boost::chrono::high_resolution_clock>
  27     class timer
  28     {
  29     public:
  30       typedef Clock                       clock;
  31       typedef typename Clock::duration    duration;
  32       typedef typename Clock::time_point  time_point;
  33
  34       explicit timer( boost::system::error_code & ec = BOOST_CHRONO_THROWS )
  35         {
  36           start(ec);
  37           }
  38
  39      ~timer() {}  // never throws
  40
  41       void start( boost::system::error_code & ec = BOOST_CHRONO_THROWS )
  42         {
  43           m_start = clock::now( ec );
  44           }
  45
  46       duration elapsed( boost::system::error_code & ec = BOOST_CHRONO_THROWS )
  47         { return clock::now( ec ) - m_start; }
  48
  49     private:
  50       time_point m_start;
  51     };
  52
  53     typedef chrono::timer< boost::chrono::system_clock > system_timer;
  54 #ifdef BOOST_CHRONO_HAS_CLOCK_STEADY
  55     typedef chrono::timer< boost::chrono::steady_clock > steady_timer;
  56 #endif
  57     typedef chrono::timer< boost::chrono::high_resolution_clock > high_resolution_timer;
  58
  59   } // namespace chrono
  60 } // namespace boost_ex
  61
  62 #endif