xbmc/threads/Timer.cpp

   1 /*
   2  *  Copyright (C) 2012-2018 Team Kodi
   3  *  This file is part of Kodi - https://kodi.tv
   4  *
   5  *  SPDX-License-Identifier: GPL-2.0-or-later
   6  *  See LICENSES/README.md for more information.
   7  */
   8
   9 #include "Timer.h"
  10
  11 #include <algorithm>
  12
  13 using namespace std::chrono_literals;
  14
  15 CTimer::CTimer(std::function<void()> const& callback)
  16   : CThread("Timer"), m_callback(callback), m_timeout(0ms), m_interval(false)
  17 { }
  18
  19 CTimer::CTimer(ITimerCallback *callback)
  20   : CTimer(std::bind(&ITimerCallback::OnTimeout, callback))
  21 { }
  22
  23 CTimer::~CTimer()
  24 {
  25   Stop(true);
  26 }
  27
  28 bool CTimer::Start(std::chrono::milliseconds timeout, bool interval /* = false */)
  29 {
  30   if (m_callback == NULL || timeout == 0ms || IsRunning())
  31     return false;
  32
  33   m_timeout = timeout;
  34   m_interval = interval;
  35
  36   Create();
  37   return true;
  38 }
  39
  40 bool CTimer::Stop(bool wait /* = false */)
  41 {
  42   if (!IsRunning())
  43     return false;
  44
  45   m_bStop = true;
  46   m_eventTimeout.Set();
  47   StopThread(wait);
  48
  49   return true;
  50 }
  51
  52 void CTimer::RestartAsync(std::chrono::milliseconds timeout)
  53 {
  54   m_timeout = timeout;
  55   m_endTime = std::chrono::steady_clock::now() + timeout;
  56   m_eventTimeout.Set();
  57 }
  58
  59 bool CTimer::Restart()
  60 {
  61   if (!IsRunning())
  62     return false;
  63
  64   Stop(true);
  65
  66   return Start(m_timeout, m_interval);
  67 }
  68
  69 float CTimer::GetElapsedSeconds() const
  70 {
  71   return GetElapsedMilliseconds() / 1000.0f;
  72 }
  73
  74 float CTimer::GetElapsedMilliseconds() const
  75 {
  76   if (!IsRunning())
  77     return 0.0f;
  78
  79   auto now = std::chrono::steady_clock::now();
  80   std::chrono::duration<float, std::milli> duration = (now - (m_endTime - m_timeout));
  81
  82   return duration.count();
  83 }
  84
  85 void CTimer::Process()
  86 {
  87   while (!m_bStop)
  88   {
  89     auto currentTime = std::chrono::steady_clock::now();
  90     m_endTime = currentTime + m_timeout;
  91
  92     // wait the necessary time
  93     auto duration = std::chrono::duration_cast<std::chrono::milliseconds>(m_endTime - currentTime);
  94
  95     if (!m_eventTimeout.Wait(duration))
  96     {
  97       currentTime = std::chrono::steady_clock::now();
  98       if (m_endTime <= currentTime)
  99       {
 100         // execute OnTimeout() callback
 101         m_callback();
 102
 103         // continue if this is an interval timer, or if it was restarted during callback
 104         if (!m_interval && m_endTime <= currentTime)
 105           break;
 106       }
 107     }
 108   }
 109 }