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  ****************************************************************************/
  
  #include "qabstracteventdispatcher.h"
  #include "qabstracteventdispatcher_p.h"
  #include "qabstractnativeeventfilter.h"
  
  #include "qthread.h"
  #include <private/qthread_p.h>
  #include <private/qcoreapplication_p.h>
  #include <private/qfreelist_p.h>
  
  QT_BEGIN_NAMESPACE
  
  // we allow for 2^24 = 8^8 = 16777216 simultaneously running timers
  struct QtTimerIdFreeListConstants : public QFreeListDefaultConstants
  {
      enum
      {
          InitialNextValue = 1,
          BlockCount = 6
      };
  
      static const int Sizes[BlockCount];
  };
  
  enum {
      Offset0 = 0x00000000,
      Offset1 = 0x00000040,
      Offset2 = 0x00000100,
      Offset3 = 0x00001000,
      Offset4 = 0x00010000,
      Offset5 = 0x00100000,
  
      Size0 = Offset1  - Offset0,
      Size1 = Offset2  - Offset1,
      Size2 = Offset3  - Offset2,
      Size3 = Offset4  - Offset3,
      Size4 = Offset5  - Offset4,
      Size5 = QtTimerIdFreeListConstants::MaxIndex - Offset5
  };
  
  const int QtTimerIdFreeListConstants::Sizes[QtTimerIdFreeListConstants::BlockCount] = {
      Size0,
      Size1,
      Size2,
      Size3,
      Size4,
      Size5
  };
  
  typedef QFreeList<void, QtTimerIdFreeListConstants> QtTimerIdFreeList;
  Q_GLOBAL_STATIC(QtTimerIdFreeList, timerIdFreeList)
  
  int QAbstractEventDispatcherPrivate::allocateTimerId()
  {
      return timerIdFreeList()->next();
  }
  
  void QAbstractEventDispatcherPrivate::releaseTimerId(int timerId)
  {
      // this function may be called by a global destructor after
      // timerIdFreeList() has been destructed
      if (QtTimerIdFreeList *fl = timerIdFreeList())
          fl->release(timerId);
  }
  
  /*!
      \class QAbstractEventDispatcher
      \inmodule QtCore
      \brief The QAbstractEventDispatcher class provides an interface to manage Qt's event queue.
  
      \ingroup events
  
      An event dispatcher receives events from the window system and other
      sources. It then sends them to the QCoreApplication or QApplication
      instance for processing and delivery. QAbstractEventDispatcher provides
      fine-grained control over event delivery.
  
      For simple control of event processing use
      QCoreApplication::processEvents().
  
      For finer control of the application's event loop, call
      instance() and call functions on the QAbstractEventDispatcher
      object that is returned. If you want to use your own instance of
      QAbstractEventDispatcher or of a QAbstractEventDispatcher
      subclass, you must install it with QCoreApplication::setEventDispatcher()
      or QThread::setEventDispatcher() \e before a default event dispatcher has
      been installed.
  
      The main event loop is started by calling
      QCoreApplication::exec(), and stopped by calling
      QCoreApplication::exit(). Local event loops can be created using
      QEventLoop.
  
      Programs that perform long operations can call processEvents()
      with a bitwise OR combination of various QEventLoop::ProcessEventsFlag
      values to control which events should be delivered.
  
      QAbstractEventDispatcher also allows the integration of an
      external event loop with the Qt event loop.
  
      \sa QEventLoop, QCoreApplication, QThread
  */
  
  /*!
      Constructs a new event dispatcher with the given \a parent.
  */
  QAbstractEventDispatcher::QAbstractEventDispatcher(QObject *parent)
      : QObject(*new QAbstractEventDispatcherPrivate, parent) {}
  
  /*!
      \internal
  */
  QAbstractEventDispatcher::QAbstractEventDispatcher(QAbstractEventDispatcherPrivate &dd,
                                                     QObject *parent)
      : QObject(dd, parent) {}
  
  /*!
      Destroys the event dispatcher.
  */
  QAbstractEventDispatcher::~QAbstractEventDispatcher()
  { }
  
  /*!
      Returns a pointer to the event dispatcher object for the specified
      \a thread. If \a thread is zero, the current thread is used. If no
      event dispatcher exists for the specified thread, this function
      returns 0.
  
      \b{Note:} If Qt is built without thread support, the \a thread
      argument is ignored.
   */
  QAbstractEventDispatcher *QAbstractEventDispatcher::instance(QThread *thread)
  {
      QThreadData *data = thread ? QThreadData::get2(thread) : QThreadData::current();
      return data->eventDispatcher.load();
  }
  
  /*!
      \fn bool QAbstractEventDispatcher::processEvents(QEventLoop::ProcessEventsFlags flags)
  
      Processes pending events that match \a flags until there are no
      more events to process. Returns \c true if an event was processed;
      otherwise returns \c false.
  
      This function is especially useful if you have a long running
      operation, and want to show its progress without allowing user
      input by using the QEventLoop::ExcludeUserInputEvents flag.
  
      If the QEventLoop::WaitForMoreEvents flag is set in \a flags, the
      behavior of this function is as follows:
  
      \list
  
      \li If events are available, this function returns after processing
      them.
  
      \li If no events are available, this function will wait until more
      are available and return after processing newly available events.
  
      \endlist
  
      If the QEventLoop::WaitForMoreEvents flag is not set in \a flags,
      and no events are available, this function will return
      immediately.
  
      \b{Note:} This function does not process events continuously; it
      returns after all available events are processed.
  
      \sa hasPendingEvents()
  */
  
  /*! \fn bool QAbstractEventDispatcher::hasPendingEvents()
      \deprecated
  
      Returns \c true if there is an event waiting; otherwise returns false. This
      function is an implementation detail for
      QCoreApplication::hasPendingEvents() and must not be called directly.
  */
  
  /*!
      \fn void QAbstractEventDispatcher::registerSocketNotifier(QSocketNotifier *notifier)
  
      Registers \a notifier with the event loop. Subclasses must
      implement this method to tie a socket notifier into another
      event loop.
  */
  
  /*! \fn void QAbstractEventDispatcher::unregisterSocketNotifier(QSocketNotifier *notifier)
  
      Unregisters \a notifier from the event dispatcher. Subclasses must
      reimplement this method to tie a socket notifier into another
      event loop. Reimplementations must call the base
      implementation.
  */
  
  /*!
      \obsolete
  
      \fn int QAbstractEventDispatcher::registerTimer(int interval, QObject *object)
  
      Registers a timer with the specified \a interval for the given \a object
      and returns the timer id.
  */
  
  /*!
      \obsolete
  
      \fn void QAbstractEventDispatcher::registerTimer(int timerId, int interval, QObject *object)
  
      Register a timer with the specified \a timerId and \a interval for the
      given \a object.
  */
  
  /*!
      Registers a timer with the specified \a interval and \a timerType for the
      given \a object and returns the timer id.
  */
  int QAbstractEventDispatcher::registerTimer(int interval, Qt::TimerType timerType, QObject *object)
  {
      int id = QAbstractEventDispatcherPrivate::allocateTimerId();
      registerTimer(id, interval, timerType, object);
      return id;
  }
  
  /*!
      \fn void QAbstractEventDispatcher::registerTimer(int timerId, int interval, Qt::TimerType timerType, QObject *object)
  
      Register a timer with the specified \a timerId, \a interval, and \a
      timerType for the given \a object.
  */
  
  /*!
      \fn bool QAbstractEventDispatcher::unregisterTimer(int timerId)
  
      Unregisters the timer with the given \a timerId.
      Returns \c true if successful; otherwise returns \c false.
  
      \sa registerTimer(), unregisterTimers()
  */
  
  /*!
      \fn bool QAbstractEventDispatcher::unregisterTimers(QObject *object)
  
      Unregisters all the timers associated with the given \a object.
      Returns \c true if all timers were successful removed; otherwise returns \c false.
  
      \sa unregisterTimer(), registeredTimers()
  */
  
  /*!
      \fn QList<TimerInfo> QAbstractEventDispatcher::registeredTimers(QObject *object) const
  
      Returns a list of registered timers for \a object. The TimerInfo struct has
      \c timerId, \c interval, and \c timerType members.
  
      \sa Qt::TimerType
  */
  
  /*!
      \fn int QAbstractEventDispatcher::remainingTime(int timerId)
  
      Returns the remaining time in milliseconds with the given \a timerId.
      If the timer is inactive, the returned value will be -1. If the timer is
      overdue, the returned value will be 0.
  
      \sa Qt::TimerType
  */
  
  /*! \fn void QAbstractEventDispatcher::wakeUp()
      \threadsafe
  
      Wakes up the event loop.
  
      \sa awake()
  */
  
  /*!
      \fn void QAbstractEventDispatcher::interrupt()
  
      Interrupts event dispatching.  The event dispatcher will
      return from processEvents() as soon as possible.
  */
  
  /*! \fn void QAbstractEventDispatcher::flush()
      \deprecated
  
      Depending from the event dispatcher implementation does nothing or
      calls QApplication::sendPostedEvents().
  */
  
  // ### DOC: Are these called when the _application_ starts/stops or just
  // when the current _event loop_ starts/stops?
  /*!
      \internal
  */
  void QAbstractEventDispatcher::startingUp()
  { }
  
  /*!
      \internal
  */
  void QAbstractEventDispatcher::closingDown()
  { }
  
  /*!
      \class QAbstractEventDispatcher::TimerInfo
      \inmodule QtCore
  
      This struct represents information about a timer:
      \l{QAbstractEventDispatcher::TimerInfo::timerId}{timerId},
      \l{QAbstractEventDispatcher::TimerInfo::interval}{interval}, and
      \l{QAbstractEventDispatcher::TimerInfo::timerType}{timerType}.
  
      \sa registeredTimers()
  */
  /*! \fn QAbstractEventDispatcher::TimerInfo::TimerInfo(int timerId, int interval, Qt::TimerType timerType)
  
      Constructs a TimerInfo struct with the given \a timerId, \a interval, and
      \a timerType.
  */
  /*!
      \variable QAbstractEventDispatcher::TimerInfo::timerId
  
      The timer's unique id.
  */
  /*!
      \variable QAbstractEventDispatcher::TimerInfo::interval
  
      The timer's interval.
  */
  /*!
      \variable QAbstractEventDispatcher::TimerInfo::timerType
  
      The timer's type
  
      \sa Qt::TimerType
  */
  
  /*!
      Installs an event filter \a filterObj for all native event filters
      received by the application.
  
      The event filter \a filterObj receives events via its \l {QAbstractNativeEventFilter::}{nativeEventFilter()}
      function, which is called for all events received by all threads.
  
      The  \l {QAbstractNativeEventFilter::}{nativeEventFilter()} function should return true
      if the event should be filtered, (in this case, stopped). It should return false to allow
      normal Qt processing to continue: the native event can then be translated
      into a QEvent and handled by the standard Qt \l{QEvent} {event} filtering,
      e.g. QObject::installEventFilter().
  
      If multiple event filters are installed, the filter that was installed last
      is activated first.
  
      \note The filter function set here receives native messages,
      that is, MSG or XEvent structs.
  
      For maximum portability, you should always try to use QEvent objects
      and QObject::installEventFilter() whenever possible.
  
      \sa QObject::installEventFilter()
  
      \since 5.0
  */
  void QAbstractEventDispatcher::installNativeEventFilter(QAbstractNativeEventFilter *filterObj)
  {
      Q_D(QAbstractEventDispatcher);
  
      // clean up unused items in the list
      d->eventFilters.removeAll(0);
      d->eventFilters.removeAll(filterObj);
      d->eventFilters.prepend(filterObj);
  }
  
  /*!
      Removes the event filter \a filter from this object. The
      request is ignored if such an event filter has not been installed.
  
      All event filters for this object are automatically removed when
      this object is destroyed.
  
      It is always safe to remove an event filter, even during event filter
      filter activation (that is, even from within the \l {QAbstractNativeEventFilter::}{nativeEventFilter()} function).
  
      \sa installNativeEventFilter(), QAbstractNativeEventFilter
      \since 5.0
  */
  void QAbstractEventDispatcher::removeNativeEventFilter(QAbstractNativeEventFilter *filter)
  {
      Q_D(QAbstractEventDispatcher);
      for (int i = 0; i < d->eventFilters.count(); ++i) {
          if (d->eventFilters.at(i) == filter) {
              d->eventFilters[i] = 0;
              break;
          }
      }
  }
  
  /*!
      Sends \a message through the event filters that were set by
      installNativeEventFilter().  This function returns \c true as soon as an
      event filter returns \c true, and false otherwise to indicate that
      the processing of the event should continue.
  
      Subclasses of QAbstractEventDispatcher \e must call this function
      for \e all messages received from the system to ensure
      compatibility with any extensions that may be used in the
      application. The type of event \a eventType is specific to the platform
      plugin chosen at run-time, and can be used to cast message to the right type.
      The \a result pointer is only used on Windows, and corresponds to the LRESULT pointer.
  
      Note that the type of \a message is platform dependent. See
      QAbstractNativeEventFilter for details.
  
      \sa installNativeEventFilter(), QAbstractNativeEventFilter::nativeEventFilter()
      \since 5.0
  */
  bool QAbstractEventDispatcher::filterNativeEvent(const QByteArray &eventType, void *message, long *result)
  {
      Q_D(QAbstractEventDispatcher);
      if (!d->eventFilters.isEmpty()) {
          // Raise the loopLevel so that deleteLater() calls in or triggered
          // by event_filter() will be processed from the main event loop.
          QScopedScopeLevelCounter scopeLevelCounter(d->threadData);
          for (int i = 0; i < d->eventFilters.size(); ++i) {
              QAbstractNativeEventFilter *filter = d->eventFilters.at(i);
              if (!filter)
                  continue;
              if (filter->nativeEventFilter(eventType, message, result))
                  return true;
          }
      }
      return false;
  }
  
  /*! \fn bool QAbstractEventDispatcher::filterEvent(void *message)
      \deprecated
  
      Calls filterNativeEvent() with an empty eventType and \a message.
      This function returns \c true as soon as an
      event filter returns \c true, and false otherwise to indicate that
      the processing of the event should continue.
  */
  
  /*! \fn bool QAbstractEventDispatcher::registerEventNotifier(QWinEventNotifier *notifier);
  
    This pure virtual method exists on windows only and has to be reimplemented by a Windows specific
    event dispatcher implementation. \a notifier is the QWinEventNotifier instance to be registered.
  
    The method should return true if the registration of \a notifier was sucessful, otherwise false.
  
    QWinEventNotifier calls this method in it's constructor and there should never be a need to call this
    method directly.
  
    \sa QWinEventNotifier, unregisterEventNotifier()
  */
  
  /*! \fn bool QAbstractEventDispatcher::unregisterEventNotifier(QWinEventNotifier *notifier);
  
    This pure virtual method exists on windows only and has to be reimplemented by a Windows specific
    event dispatcher implementation. \a notifier is the QWinEventNotifier instance to be unregistered.
  
    QWinEventNotifier calls this method in it's destructor and there should never be a need to call this
    method directly.
  
    \sa QWinEventNotifier, registerEventNotifier()
  */
  
  /*! \fn void QAbstractEventDispatcher::awake()
  
      This signal is emitted after the event loop returns from a
      function that could block.
  
      \sa wakeUp(), aboutToBlock()
  */
  
  /*! \fn void QAbstractEventDispatcher::aboutToBlock()
  
      This signal is emitted before the event loop calls a function that
      could block.
  
      \sa awake()
  */
  
  QT_END_NAMESPACE
  
  #include "moc_qabstracteventdispatcher.cpp"
  