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// qfutureinterface.h included from qfuture.h

#include "qfuture.h"

#ifndef QT_NO_QFUTURE

#include <QtCore/qatomic.h>

#include <QtCore/qthread.h>

#include <QtCore/qthreadpool.h>

#include <private/qthreadpool_p.h>

#include "qfutureinterface_p.h"

QT_BEGIN_NAMESPACE

enum {

    MaxProgressEmitsPerSecond = 25

};

QFutureInterfaceBase::QFutureInterfaceBase(State initialState)

    : d(new QFutureInterfaceBasePrivate(initialState))

{ }

QFutureInterfaceBase::QFutureInterfaceBase(const QFutureInterfaceBase &other)

    : d(other.d)

{

    d->refCount.ref();

}

QFutureInterfaceBase::~QFutureInterfaceBase()

{

    if (!d->refCount.deref())

        delete d;

}

void QFutureInterfaceBase::cancel()

{

    QMutexLocker locker(&d->m_mutex);

    if (d->state & Canceled)

        return;

    d->state = State((d->state & ~Paused) | Canceled);

    d->waitCondition.wakeAll();

    d->pausedWaitCondition.wakeAll();

    d->sendCallOut(QFutureCallOutEvent(QFutureCallOutEvent::Canceled));

}

void QFutureInterfaceBase::setPaused(bool paused)

{

    QMutexLocker locker(&d->m_mutex);

    if (paused) {

        d->state = State(d->state | Paused);

        d->sendCallOut(QFutureCallOutEvent(QFutureCallOutEvent::Paused));

    } else {

        d->state = State(d->state & ~Paused);

        d->pausedWaitCondition.wakeAll();

        d->sendCallOut(QFutureCallOutEvent(QFutureCallOutEvent::Resumed));

    }

}

void QFutureInterfaceBase::togglePaused()

{

    QMutexLocker locker(&d->m_mutex);

    if (d->state & Paused) {

        d->state = State(d->state & ~Paused);

        d->pausedWaitCondition.wakeAll();

        d->sendCallOut(QFutureCallOutEvent(QFutureCallOutEvent::Resumed));

    } else {

        d->state = State(d->state | Paused);

        d->sendCallOut(QFutureCallOutEvent(QFutureCallOutEvent::Paused));

    }

}

void QFutureInterfaceBase::setThrottled(bool enable)

{

    // bail out if we are not changing the state

    if ((enable && (d->state & Throttled)) || (!enable && !(d->state & Throttled)))

        return;

    // lock and change the state

    QMutexLocker lock(&d->m_mutex);

    if (enable) {

        d->state  = State(d->state | Throttled);

    } else {

        d->state  = State(d->state & ~Throttled);

        if (!(d->state & Paused))

            d->pausedWaitCondition.wakeAll();

    }

}

bool QFutureInterfaceBase::isRunning() const

{

    return queryState(Running);

}

bool QFutureInterfaceBase::isStarted() const

{

    return queryState(Started);

}

bool QFutureInterfaceBase::isCanceled() const

{

    return queryState(Canceled);

}

bool QFutureInterfaceBase::isFinished() const

{

    return queryState(Finished);

}

bool QFutureInterfaceBase::isPaused() const

{

    return queryState(Paused);

}

bool QFutureInterfaceBase::isThrottled() const

{

    return queryState(Throttled);

}

bool QFutureInterfaceBase::isResultReadyAt(int index) const

{

    QMutexLocker lock(&d->m_mutex);

    return d->internal_isResultReadyAt(index);

}

bool QFutureInterfaceBase::waitForNextResult()

{

    QMutexLocker lock(&d->m_mutex);

    return d->internal_waitForNextResult();

}

void QFutureInterfaceBase::waitForResume()

{

    // return early if possible to avoid taking the mutex lock.

    if ((d->state & Paused) == false || (d->state & Canceled))

        return;

    QMutexLocker lock(&d->m_mutex);

    if ((d->state & Paused) == false || (d->state & Canceled))

        return;

    // decrease active thread count since this thread will wait.

    QThreadPool::globalInstance()->releaseThread();

    d->pausedWaitCondition.wait(&d->m_mutex);

    QThreadPool::globalInstance()->reserveThread();

}

int QFutureInterfaceBase::progressValue() const

{

    return d->m_progressValue;

}

int QFutureInterfaceBase::progressMinimum() const

{

    return d->m_progressMinimum;

}

int QFutureInterfaceBase::progressMaximum() const

{

    return d->m_progressMaximum;

}

int QFutureInterfaceBase::resultCount() const

{

    QMutexLocker lock(&d->m_mutex);

    return d->internal_resultCount();

}

QString QFutureInterfaceBase::progressText() const

{

    QMutexLocker locker(&d->m_mutex);

    return d->m_progressText;

}

bool QFutureInterfaceBase::isProgressUpdateNeeded() const

{

    QMutexLocker locker(&d->m_mutex);

    return (d->progressTime.elapsed() > (1000 / MaxProgressEmitsPerSecond));

}

void QFutureInterfaceBase::reportStarted()

{

    QMutexLocker locker(&d->m_mutex);

    if ((d->state & Started) || (d->state & Canceled) || (d->state & Finished))

        return;

    d->setState(State(Started | Running));

    d->sendCallOut(QFutureCallOutEvent(QFutureCallOutEvent::Started));

}

void QFutureInterfaceBase::reportCanceled()

{

    cancel();

}

#ifndef QT_NO_EXCEPTIONS

void QFutureInterfaceBase::reportException(const QtConcurrent::Exception &exception)

{

    QMutexLocker locker(&d->m_mutex);

    if ((d->state & Canceled) || (d->state & Finished))

        return;

    d->m_exceptionStore.setException(exception);

    d->state = State(d->state | Canceled);

    d->waitCondition.wakeAll();

    d->pausedWaitCondition.wakeAll();

    d->sendCallOut(QFutureCallOutEvent(QFutureCallOutEvent::Canceled));

}

#endif

void QFutureInterfaceBase::reportFinished()

{

    QMutexLocker locker(&d->m_mutex);

    if (!(d->state & Finished)) {

        d->state = State((d->state & ~Running) | Finished);

        d->waitCondition.wakeAll();

        d->sendCallOut(QFutureCallOutEvent(QFutureCallOutEvent::Finished));

    }

}

void QFutureInterfaceBase::setExpectedResultCount(int resultCount)

{

    if (d->manualProgress == false)

        setProgressRange(0, resultCount);

    d->m_expectedResultCount = resultCount;

}

int QFutureInterfaceBase::expectedResultCount()

{

    return d->m_expectedResultCount;

}

bool QFutureInterfaceBase::queryState(State state) const

{

    return (d->state & state);

}

void QFutureInterfaceBase::waitForResult(int resultIndex)

{

    d->m_exceptionStore.throwPossibleException();

    if (!(d->state & Running))

        return;

    // To avoid deadlocks and reduce the number of threads used, try to 

    // run the runnable in the current thread.

    QThreadPool::globalInstance()->d_func()->stealRunnable(d->runnable);

    QMutexLocker lock(&d->m_mutex);

    if (!(d->state & Running))

        return;

    const int waitIndex = (resultIndex == -1) ? INT_MAX : resultIndex;

    while ((d->state & Running) && d->internal_isResultReadyAt(waitIndex) == false)

        d->waitCondition.wait(&d->m_mutex);

    d->m_exceptionStore.throwPossibleException();

}

void QFutureInterfaceBase::waitForFinished()

{

    if (d->state & Running) {

        QThreadPool::globalInstance()->d_func()->stealRunnable(d->runnable);

        QMutexLocker lock(&d->m_mutex);

        while (d->state & Running)

            d->waitCondition.wait(&d->m_mutex);

    }

    d->m_exceptionStore.throwPossibleException();

}

void QFutureInterfaceBase::reportResultsReady(int beginIndex, int endIndex)

{

    if ((d->state & Canceled) || (d->state & Finished) || beginIndex == endIndex)

        return;

    d->waitCondition.wakeAll();

    if (d->manualProgress == false) {

        if (d->internal_updateProgress(d->m_progressValue + endIndex - beginIndex) == false) {

            d->sendCallOut(QFutureCallOutEvent(QFutureCallOutEvent::ResultsReady,

                                               beginIndex,

                                               endIndex));

            return;

        }

        d->sendCallOuts(QFutureCallOutEvent(QFutureCallOutEvent::Progress,

                                            d->m_progressValue,

                                            d->m_progressText),

                        QFutureCallOutEvent(QFutureCallOutEvent::ResultsReady,

                                            beginIndex,

                                            endIndex));

        return;

    }

    d->sendCallOut(QFutureCallOutEvent(QFutureCallOutEvent::ResultsReady, beginIndex, endIndex));

}

void QFutureInterfaceBase::setRunnable(QRunnable *runnable)

{

    d->runnable = runnable;

}

void QFutureInterfaceBase::setFilterMode(bool enable)

{

    QMutexLocker locker(&d->m_mutex);

    resultStoreBase().setFilterMode(enable);

}

void QFutureInterfaceBase::setProgressRange(int minimum, int maximum)

{

    QMutexLocker locker(&d->m_mutex);

    d->m_progressMinimum = minimum;

    d->m_progressMaximum = maximum;

    d->sendCallOut(QFutureCallOutEvent(QFutureCallOutEvent::ProgressRange, minimum, maximum));

}

void QFutureInterfaceBase::setProgressValue(int progressValue)

{

    setProgressValueAndText(progressValue, QString());

}

void QFutureInterfaceBase::setProgressValueAndText(int progressValue,

                                                   const QString &progressText)

{

    QMutexLocker locker(&d->m_mutex);

    if (d->manualProgress == false)

        d->manualProgress = true;

    if (d->m_progressValue >= progressValue)

        return;

    if ((d->state & Canceled) || (d->state & Finished))

        return;

    if (d->internal_updateProgress(progressValue, progressText)) {

        d->sendCallOut(QFutureCallOutEvent(QFutureCallOutEvent::Progress,

                                           d->m_progressValue,

                                           d->m_progressText));

    }

}

QMutex *QFutureInterfaceBase::mutex() const

{

    return &d->m_mutex;

}

QtConcurrent::internal::ExceptionStore &QFutureInterfaceBase::exceptionStore()

{

    return d->m_exceptionStore;

}

QtConcurrent::ResultStoreBase &QFutureInterfaceBase::resultStoreBase()

{

    return d->m_results;

}

const QtConcurrent::ResultStoreBase &QFutureInterfaceBase::resultStoreBase() const

{

    return d->m_results;

}

QFutureInterfaceBase &QFutureInterfaceBase::operator=(const QFutureInterfaceBase &other)

{

    other.d->refCount.ref();

    if (!d->refCount.deref())

        delete d;

    d = other.d;

    return *this;

}

bool QFutureInterfaceBase::referenceCountIsOne() const

{

    return d->refCount == 1;

}

QFutureInterfaceBasePrivate::QFutureInterfaceBasePrivate(QFutureInterfaceBase::State initialState)

    : refCount(1), m_progressValue(0), m_progressMinimum(0), m_progressMaximum(0),

      state(initialState), progressTimeStarted(false), pendingResults(0),

      manualProgress(false), m_expectedResultCount(0), runnable(0)

{ }

int QFutureInterfaceBasePrivate::internal_resultCount() const

{

    return m_results.count(); // ### subtract canceled results.

}

bool QFutureInterfaceBasePrivate::internal_isResultReadyAt(int index) const

{

    return (m_results.contains(index));

}

bool QFutureInterfaceBasePrivate::internal_waitForNextResult()

{

    if (m_results.hasNextResult())

        return true;

    while ((state & QFutureInterfaceBase::Running) && m_results.hasNextResult() == false)

        waitCondition.wait(&m_mutex);

    return (!(state & QFutureInterfaceBase::Canceled) && m_results.hasNextResult());

}

bool QFutureInterfaceBasePrivate::internal_updateProgress(int progress,

                                                          const QString &progressText)

{

    if (m_progressValue >= progress)

        return false;

    m_progressValue = progress;

    m_progressText = progressText;

    if (progressTimeStarted == true && m_progressValue != m_progressMaximum) // make sure the first and last steps are emitted.

        if (progressTime.elapsed() < (1000 / MaxProgressEmitsPerSecond))

            return false;

    progressTime.start();

    progressTimeStarted = true;

    return true;

}

void QFutureInterfaceBasePrivate::internal_setThrottled(bool enable)

{

    // bail out if we are not changing the state

    if ((enable && (state & QFutureInterfaceBase::Throttled))

        || (!enable && !(state & QFutureInterfaceBase::Throttled)))

        return;

    // change the state

    if (enable) {

        state  = QFutureInterfaceBase::State(state | QFutureInterfaceBase::Throttled);

    } else {

        state  = QFutureInterfaceBase::State(state & ~QFutureInterfaceBase::Throttled);

        if (!(state & QFutureInterfaceBase::Paused))

            pausedWaitCondition.wakeAll();

    }

}

void QFutureInterfaceBasePrivate::sendCallOut(const QFutureCallOutEvent &callOutEvent)

{

    if (outputConnections.isEmpty())

        return;

    for (int i = 0; i < outputConnections.count(); ++i)

        outputConnections.at(i)->postCallOutEvent(callOutEvent);

}

void QFutureInterfaceBasePrivate::sendCallOuts(const QFutureCallOutEvent &callOutEvent1,

                                     const QFutureCallOutEvent &callOutEvent2)

{

    if (outputConnections.isEmpty())

        return;

    for (int i = 0; i < outputConnections.count(); ++i) {

        QFutureCallOutInterface *interface = outputConnections.at(i);

        interface->postCallOutEvent(callOutEvent1);

        interface->postCallOutEvent(callOutEvent2);

    }

}

// This function connects an output interface (for example a QFutureWatcher)

// to this future. While holding the lock we check the state and ready results

// and add the appropriate callouts to the queue. In order to avoid deadlocks,

// the actual callouts are made at the end while not holding the lock.

void QFutureInterfaceBasePrivate::connectOutputInterface(QFutureCallOutInterface *interface)

{

    QMutexLocker locker(&m_mutex);

    if (state & QFutureInterfaceBase::Started) {

        interface->postCallOutEvent(QFutureCallOutEvent(QFutureCallOutEvent::Started));

        interface->postCallOutEvent(QFutureCallOutEvent(QFutureCallOutEvent::ProgressRange,

                                                        m_progressMinimum,

                                                        m_progressMaximum));

        interface->postCallOutEvent(QFutureCallOutEvent(QFutureCallOutEvent::Progress,

                                                        m_progressValue,

                                                        m_progressText));

    }

    QtConcurrent::ResultIteratorBase it = m_results.begin();

    while (it != m_results.end()) {

        const int begin = it.resultIndex();

        const int end = begin + it.batchSize();

        interface->postCallOutEvent(QFutureCallOutEvent(QFutureCallOutEvent::ResultsReady,