File indexing completed on 2024-05-05 17:50:04

 /*
    Copyright (C) 2014 Andreas Hartmetz <ahartmetz@gmail.com>
 
    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.
 
    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Library General Public License for more details.
 
    You should have received a copy of the GNU Library General Public License
    along with this library; see the file COPYING.LGPL.  If not, write to
    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
    Boston, MA 02110-1301, USA.
 
    Alternatively, this file is available under the Mozilla Public License
    Version 1.1.  You may obtain a copy of the License at
    http://www.mozilla.org/MPL/
 */
 
 #include "timer.h"
 
 #include "eventdispatcher.h"
 #include "eventdispatcher_p.h"
 #include "icompletionlistener.h"
 #include "platformtime.h"
 
 #include <algorithm>
 #include <cassert>
 #include <iostream>
 #include <limits>
 
 Timer::Timer(EventDispatcher *dispatcher)
    : m_eventDispatcher(dispatcher),
      m_completionListener(nullptr),
      m_reentrancyGuard(nullptr),
      m_interval(0),
      m_isRunning(false),
      m_isRepeating(true),
      m_nextDueTime(0),
      m_serial(0)
 {
 }
 
 Timer::~Timer()
 {
     // Rationale for "|| m_reentrancyGuard": While triggered, we must be removed from the event
     // dispatcher's timer map before it may dereference the then dangling pointer to this Timer.
     if (m_isRunning || m_reentrancyGuard) {
         EventDispatcherPrivate::get(m_eventDispatcher)->removeTimer(this);
     }
 
     if (m_reentrancyGuard) {
         *m_reentrancyGuard = false;
         m_reentrancyGuard = nullptr;
     }
 }
 
 void Timer::start(int msec)
 {
     if (msec < 0) {
         std::cerr << "Timer::start(): interval cannot be negative!\n";
     }
     // restart if already running
     if (!m_reentrancyGuard && m_isRunning) {
         EventDispatcherPrivate::get(m_eventDispatcher)->removeTimer(this);
     }
     m_interval = msec;
     m_isRunning = true;
     if (!m_reentrancyGuard) {
         EventDispatcherPrivate::get(m_eventDispatcher)->addTimer(this);
     }
 }
 
 void Timer::stop()
 {
     setRunning(false);
 }
 
 void Timer::setRunning(bool run)
 {
     if (m_isRunning == run) {
         return;
     }
     m_isRunning = run;
     if (!m_reentrancyGuard) {
         EventDispatcherPrivate *const ep = EventDispatcherPrivate::get(m_eventDispatcher);
         if (run) {
             ep->addTimer(this);
         } else {
             ep->removeTimer(this);
         }
     }
 }
 
 bool Timer::isRunning() const
 {
     return m_isRunning;
 }
 
 void Timer::setInterval(int msec)
 {
     if (msec < 0) {
         std::cerr << "Timer::setInterval(): interval cannot be negative!\n";
     }
     if (m_interval == msec) {
         return;
     }
     m_interval = msec;
     if (m_isRunning && !m_reentrancyGuard) {
         EventDispatcherPrivate *const ep = EventDispatcherPrivate::get(m_eventDispatcher);
         ep->removeTimer(this);
         ep->addTimer(this);
     }
 }
 
 int Timer::interval() const
 {
     return m_interval;
 }
 
 void Timer::setRepeating(bool repeating)
 {
     m_isRepeating = repeating;
 }
 
 bool Timer::isRepeating() const
 {
     return m_isRepeating;
 }
 
 int Timer::remainingTime() const
 {
     if (!m_isRunning) {
         return -1;
     }
     const uint64 currentTime = PlatformTime::monotonicMsecs();
     if (currentTime > m_nextDueTime) {
         return 0;
     }
     return std::min(uint64(std::numeric_limits<int>::max()), m_nextDueTime - currentTime);
 }
 
 #if defined __GNUC__ && __GNUC__ >= 12
 #define GCC_12
 #endif
 
 #ifdef GCC_12
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wdangling-pointer"
 #endif
 void Timer::trigger()
 {
     assert(m_isRunning);
     if (m_reentrancyGuard) {
         return;
     }
     if (!m_isRepeating) {
         m_isRunning = false;
     }
 
     // Changes to this timer while in the callback require special treatment. m_reentrancyGuard
     // helps provide that.
     bool alive = true;
     m_reentrancyGuard = &alive;
     if (m_completionListener) {
         m_completionListener->handleCompletion(this);
     }
     // if we we've been destroyed, we don't touch the member variable
     if (alive) {
         assert(m_reentrancyGuard);
         m_reentrancyGuard = nullptr;
     }
 }
 #ifdef GCC_12
 #pragma GCC diagnostic pop
 #endif
 
 void Timer::setCompletionListener(ICompletionListener *client)
 {
     m_completionListener = client;
 }
 
 ICompletionListener *Timer::completionClient() const
 {
     return m_completionListener;
 }
 
 EventDispatcher *Timer::eventDispatcher() const
 {
     return m_eventDispatcher;
 }