qquickpixmapcache.cpp

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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
#include <QtQuick/private/qquickpixmapcache_p.h>
#include <QtQuick/private/qquickimageprovider_p.h>
#include <QtQuick/private/qquickprofiler_p.h>
#include <QtQuick/private/qsgcontext_p.h>
#include <QtQuick/private/qsgrenderer_p.h>
#include <QtQuick/private/qsgtexturereader_p.h>
#include <QtQuick/qquickwindow.h>
 
#include <QtGui/private/qguiapplication_p.h>
#include <QtGui/private/qimage_p.h>
#include <QtGui/qpa/qplatformintegration.h>
#include <QtGui/qimagereader.h>
#include <QtGui/qpixmapcache.h>
 
#include <QtQml/private/qqmlglobal_p.h>
#include <QtQml/private/qqmlengine_p.h>
#include <QtQml/qqmlfile.h>
 
#include <QtCore/private/qobject_p.h>
#include <QtCore/qcoreapplication.h>
#include <QtCore/qhash.h>
#include <QtCore/qfile.h>
#include <QtCore/qthread.h>
#include <QtCore/qmutex.h>
#include <QtCore/qbuffer.h>
#include <QtCore/qdebug.h>
#include <QtCore/qmetaobject.h>
#include <QtCore/qscopeguard.h>
 
#if QT_CONFIG(qml_network)
#include <QtQml/qqmlnetworkaccessmanagerfactory.h>
#include <QtNetwork/qnetworkreply.h>
#include <QtNetwork/qsslerror.h>
#endif
 
#include <private/qdebug_p.h>
 
#define IMAGEREQUEST_MAX_NETWORK_REQUEST_COUNT 8
 
// After QQuickPixmapCache::unreferencePixmap() it may get deleted via a timer in 30 seconds
#define CACHE_EXPIRE_TIME 30
 
// How many (1/4) of the unreferenced pixmaps to delete in QQuickPixmapCache::timerEvent()
#define CACHE_REMOVAL_FRACTION 4
 
#define PIXMAP_PROFILE(Code) Q_QUICK_PROFILE(QQuickProfiler::ProfilePixmapCache, Code)
 
#if QT_CONFIG(thread) && !defined(Q_OS_WASM)
#  define USE_THREADED_DOWNLOAD 1
#else
#  define USE_THREADED_DOWNLOAD 0
#endif
 
QT_BEGIN_NAMESPACE
 
using namespace Qt::Literals::StringLiterals;
 
Q_DECLARE_LOGGING_CATEGORY(lcQsgLeak)
 
#if defined(QT_DEBUG) && QT_CONFIG(thread)
class ThreadAffinityMarker
{
public:
    ThreadAffinityMarker() { attachToCurrentThread(); }
 
    void assertOnAssignedThread()
    {
        QMutexLocker locker(&m_mutex);
        if (!m_assignedThread)
            attachToCurrentThread();
        Q_ASSERT_X(m_assignedThread == QThread::currentThreadId(), Q_FUNC_INFO,
                   "Running on a wrong thread!");
    }
 
    void detachFromCurrentThread()
    {
        QMutexLocker locker(&m_mutex);
        m_assignedThread = nullptr;
    }
 
    void attachToCurrentThread() { m_assignedThread = QThread::currentThreadId(); }
 
private:
    Qt::HANDLE m_assignedThread;
    QMutex m_mutex;
};
#  define Q_THREAD_AFFINITY_MARKER(x) ThreadAffinityMarker x
#  define Q_ASSERT_CALLED_ON_VALID_THREAD(x) x.assertOnAssignedThread()
#  define Q_DETACH_THREAD_AFFINITY_MARKER(x) x.detachFromCurrentThread()
#else
#  define Q_THREAD_AFFINITY_MARKER(x)
#  define Q_ASSERT_CALLED_ON_VALID_THREAD(x)
#  define Q_DETACH_THREAD_AFFINITY_MARKER(x)
#endif
 
const QLatin1String QQuickPixmap::itemGrabberScheme = QLatin1String("itemgrabber");
 
Q_LOGGING_CATEGORY(lcImg, "qt.quick.image")
 
 
static int cache_limit = 2048 * 1024;
 
static inline QString imageProviderId(const QUrl &url)
{
    return url.host();
}
 
static inline QString imageId(const QUrl &url)
{
    return url.toString(QUrl::RemoveScheme | QUrl::RemoveAuthority).mid(1);
}
 
QQuickDefaultTextureFactory::QQuickDefaultTextureFactory(const QImage &image)
{
    if (image.format() == QImage::Format_ARGB32_Premultiplied
            || image.format() == QImage::Format_RGB32) {
        im = image;
    } else {
        im = image.convertToFormat(QImage::Format_ARGB32_Premultiplied);
    }
    size = im.size();
}
 
 
QSGTexture *QQuickDefaultTextureFactory::createTexture(QQuickWindow *window) const
{
    QSGTexture *t = window->createTextureFromImage(im, QQuickWindow::TextureCanUseAtlas);
    static bool transient = qEnvironmentVariableIsSet("QSG_TRANSIENT_IMAGES");
    if (transient)
        const_cast<QQuickDefaultTextureFactory *>(this)->im = QImage();
    return t;
}
 
class QQuickPixmapReader;
class QQuickPixmapData;
class QQuickPixmapReply : public QObject
{
    Q_OBJECT
public:
    enum ReadError { NoError, Loading, Decoding };
 
    QQuickPixmapReply(QQuickPixmapData *);
    ~QQuickPixmapReply();
 
    QQuickPixmapData *data;
    QQmlEngine *engineForReader; // always access reader inside readerMutex
    QRect requestRegion;
    QSize requestSize;
    QUrl url;
 
    bool loading;
    QQuickImageProviderOptions providerOptions;
 
    class Event : public QEvent {
        Q_EVENT_DISABLE_COPY(Event);
    public:
        Event(ReadError, const QString &, const QSize &, QQuickTextureFactory *factory);
        ~Event();
 
        ReadError error;
        QString errorString;
        QSize implicitSize;
        QQuickTextureFactory *textureFactory;
    };
    void postReply(ReadError, const QString &, const QSize &, QQuickTextureFactory *factory);
 
 
Q_SIGNALS:
    void finished();
    void downloadProgress(qint64, qint64);
 
protected:
    bool event(QEvent *event) override;
 
private:
    Q_DISABLE_COPY(QQuickPixmapReply)
 
public:
    static int finishedMethodIndex;
    static int downloadProgressMethodIndex;
};
 
class ReaderThreadExecutionEnforcer : public QObject
{
    Q_OBJECT
public:
    enum Event {
        ProcessJobs = QEvent::User,
    };
 
    ReaderThreadExecutionEnforcer(QQuickPixmapReader *reader);
 
    void processJobsOnReaderThreadLater();
 
public slots:
    void asyncResponseFinished(QQuickImageResponse *response);
    void asyncResponseFinished();
private slots:
    void networkRequestDone();
private:
    Q_DISABLE_COPY(ReaderThreadExecutionEnforcer)
    bool event(QEvent *e) override;
 
    QQuickPixmapReader *reader;
};
 
class QQuickPixmapData;
class QQuickPixmapReader : public QThread
{
    Q_OBJECT
public:
    QQuickPixmapReader(QQmlEngine *eng);
    ~QQuickPixmapReader();
 
    QQuickPixmapReply *getImage(QQuickPixmapData *);
    void cancel(QQuickPixmapReply *rep);
 
    static QQuickPixmapReader *instance(QQmlEngine *engine);
    static QQuickPixmapReader *existingInstance(QQmlEngine *engine);
    void startJob(QQuickPixmapReply *job);
 
protected:
    void run() override;
 
private:
    Q_DISABLE_COPY(QQuickPixmapReader)
    friend class ReaderThreadExecutionEnforcer;
    void processJobs();
    void processJob(QQuickPixmapReply *, const QUrl &, const QString &, QQuickImageProvider::ImageType, const QSharedPointer<QQuickImageProvider> &);
#if QT_CONFIG(qml_network)
    void networkRequestDone(QNetworkReply *);
#endif
    void asyncResponseFinished(QQuickImageResponse *);
 
    QList<QQuickPixmapReply*> jobs;
    QList<QQuickPixmapReply *> cancelledJobs;
    QQmlEngine *engine;
 
#if QT_CONFIG(quick_pixmap_cache_threaded_download)
    ReaderThreadExecutionEnforcer *readerThreadExecutionEnforcer()
    {
        return runLoopReaderThreadExecutionEnforcer;
    }
    QObject *eventLoopQuitHack;
    QMutex mutex;
    ReaderThreadExecutionEnforcer *runLoopReaderThreadExecutionEnforcer = nullptr;
#else
    ReaderThreadExecutionEnforcer *readerThreadExecutionEnforcer()
    {
        return ownedReaderThreadExecutionEnforcer.get();
    }
    std::unique_ptr<ReaderThreadExecutionEnforcer> ownedReaderThreadExecutionEnforcer;
#endif
 
#if QT_CONFIG(qml_network)
    QNetworkAccessManager *networkAccessManager();
    QNetworkAccessManager *accessManager;
    QHash<QNetworkReply*,QQuickPixmapReply*> networkJobs;
#endif
    QHash<QQuickImageResponse*,QQuickPixmapReply*> asyncResponses;
 
    Q_THREAD_AFFINITY_MARKER(m_creatorThreadAffinityMarker);
    Q_THREAD_AFFINITY_MARKER(m_readerThreadAffinityMarker);
 
    static int replyDownloadProgressMethodIndex;
    static int replyFinishedMethodIndex;
    static int downloadProgressMethodIndex;
    static int threadNetworkRequestDoneMethodIndex;
    static QHash<QQmlEngine *,QQuickPixmapReader*> readers;
public:
    static QMutex readerMutex;
};
 
#if QT_CONFIG(quick_pixmap_cache_threaded_download)
#  define PIXMAP_READER_LOCK() QMutexLocker locker(&mutex)
#else
#  define PIXMAP_READER_LOCK()
#endif
 
class QQuickPixmapCache;
 
class QQuickPixmapData
{
public:
    QQuickPixmapData(const QUrl &u, const QRect &r, const QSize &rs,
                     const QQuickImageProviderOptions &po, const QString &e)
    : refCount(1), frameCount(1), frame(0), inCache(false), pixmapStatus(QQuickPixmap::Error),
      url(u), errorString(e), requestRegion(r), requestSize(rs),
      providerOptions(po), appliedTransform(QQuickImageProviderOptions::UsePluginDefaultTransform),
      textureFactory(nullptr), reply(nullptr), prevUnreferenced(nullptr),
      prevUnreferencedPtr(nullptr), nextUnreferenced(nullptr)
#ifdef Q_OS_WEBOS
    , storeToCache(true)
#endif
    {
    }
 
    QQuickPixmapData(const QUrl &u, const QRect &r, const QSize &s, const QQuickImageProviderOptions &po,
                     QQuickImageProviderOptions::AutoTransform aTransform, int frame=0, int frameCount=1)
    : refCount(1), frameCount(frameCount), frame(frame), inCache(false), pixmapStatus(QQuickPixmap::Loading),
      url(u), requestRegion(r), requestSize(s),
      providerOptions(po), appliedTransform(aTransform),
      textureFactory(nullptr), reply(nullptr), prevUnreferenced(nullptr), prevUnreferencedPtr(nullptr),
      nextUnreferenced(nullptr)
#ifdef Q_OS_WEBOS
    , storeToCache(true)
#endif
    {
    }
 
    QQuickPixmapData(const QUrl &u, QQuickTextureFactory *texture,
                     const QSize &s, const QRect &r, const QSize &rs, const QQuickImageProviderOptions &po,
                     QQuickImageProviderOptions::AutoTransform aTransform, int frame=0, int frameCount=1)
    : refCount(1), frameCount(frameCount), frame(frame), inCache(false), pixmapStatus(QQuickPixmap::Ready),
      url(u), implicitSize(s), requestRegion(r), requestSize(rs),
      providerOptions(po), appliedTransform(aTransform),
      textureFactory(texture), reply(nullptr), prevUnreferenced(nullptr),
      prevUnreferencedPtr(nullptr), nextUnreferenced(nullptr)
#ifdef Q_OS_WEBOS
    , storeToCache(true)
#endif
    {
    }
 
    QQuickPixmapData(QQuickTextureFactory *texture)
    : refCount(1), frameCount(1), frame(0), inCache(false), pixmapStatus(QQuickPixmap::Ready),
      appliedTransform(QQuickImageProviderOptions::UsePluginDefaultTransform),
      textureFactory(texture), reply(nullptr), prevUnreferenced(nullptr),
      prevUnreferencedPtr(nullptr), nextUnreferenced(nullptr)
#ifdef Q_OS_WEBOS
    , storeToCache(true)
#endif
    {
        if (texture)
            requestSize = implicitSize = texture->textureSize();
    }
 
    ~QQuickPixmapData()
    {
        delete textureFactory;
    }
 
    int cost() const;
    void addref();
    void release(QQuickPixmapCache *store = nullptr);
    void addToCache();
    void removeFromCache(QQuickPixmapCache *store = nullptr);
 
    uint refCount;
    int frameCount;
    int frame;
 
    bool inCache:1;
 
    QQuickPixmap::Status pixmapStatus;
    QUrl url;
    QString errorString;
    QSize implicitSize;
    QRect requestRegion;
    QSize requestSize;
    QQuickImageProviderOptions providerOptions;
    QQuickImageProviderOptions::AutoTransform appliedTransform;
    QColorSpace targetColorSpace;
 
    QIODevice *specialDevice = nullptr;
 
    // actual image data, after loading
    QQuickTextureFactory *textureFactory;
 
    QQuickPixmapReply *reply;
 
    // prev/next pointers to form a linked list for dereferencing pixmaps that are currently unused
    // (those get lazily deleted in QQuickPixmapCache::shrinkCache())
    QQuickPixmapData *prevUnreferenced;
    QQuickPixmapData**prevUnreferencedPtr;
    QQuickPixmapData *nextUnreferenced;
 
#ifdef Q_OS_WEBOS
    bool storeToCache;
#endif
 
private:
    Q_DISABLE_COPY(QQuickPixmapData)
};
 
int QQuickPixmapReply::finishedMethodIndex = -1;
int QQuickPixmapReply::downloadProgressMethodIndex = -1;
 
// XXX
QHash<QQmlEngine *,QQuickPixmapReader*> QQuickPixmapReader::readers;
QMutex QQuickPixmapReader::readerMutex;
 
int QQuickPixmapReader::replyDownloadProgressMethodIndex = -1;
int QQuickPixmapReader::replyFinishedMethodIndex = -1;
int QQuickPixmapReader::downloadProgressMethodIndex = -1;
int QQuickPixmapReader::threadNetworkRequestDoneMethodIndex = -1;
 
void QQuickPixmapReply::postReply(ReadError error, const QString &errorString,
                                        const QSize &implicitSize, QQuickTextureFactory *factory)
{
    loading = false;
    QCoreApplication::postEvent(this, new Event(error, errorString, implicitSize, factory));
}
 
QQuickPixmapReply::Event::Event(ReadError e, const QString &s, const QSize &iSize, QQuickTextureFactory *factory)
    : QEvent(QEvent::User), error(e), errorString(s), implicitSize(iSize), textureFactory(factory)
{
}
 
QQuickPixmapReply::Event::~Event()
{
    delete textureFactory;
}
 
#if QT_CONFIG(qml_network)
QNetworkAccessManager *QQuickPixmapReader::networkAccessManager()
{
    if (!accessManager) {
        Q_ASSERT(readerThreadExecutionEnforcer());
        accessManager = QQmlEnginePrivate::get(engine)->createNetworkAccessManager(
                readerThreadExecutionEnforcer());
    }
    return accessManager;
}
#endif
 
static void maybeRemoveAlpha(QImage *image)
{
    // If the image
    if (image->hasAlphaChannel() && image->data_ptr()
            && !image->data_ptr()->checkForAlphaPixels()) {
        switch (image->format()) {
        case QImage::Format_RGBA8888:
        case QImage::Format_RGBA8888_Premultiplied:
            if (image->data_ptr()->convertInPlace(QImage::Format_RGBX8888, Qt::AutoColor))
                break;
 
            *image = image->convertToFormat(QImage::Format_RGBX8888);
            break;
        case QImage::Format_A2BGR30_Premultiplied:
            if (image->data_ptr()->convertInPlace(QImage::Format_BGR30, Qt::AutoColor))
                break;
 
            *image = image->convertToFormat(QImage::Format_BGR30);
            break;
        case QImage::Format_A2RGB30_Premultiplied:
            if (image->data_ptr()->convertInPlace(QImage::Format_RGB30, Qt::AutoColor))
                break;
 
            *image = image->convertToFormat(QImage::Format_RGB30);
            break;
        default:
            if (image->data_ptr()->convertInPlace(QImage::Format_RGB32, Qt::AutoColor))
                break;
 
            *image = image->convertToFormat(QImage::Format_RGB32);
            break;
        }
    }
}
 
static bool readImage(const QUrl& url, QIODevice *dev, QImage *image, QString *errorString, QSize *impsize, int *frameCount,
                      const QRect &requestRegion, const QSize &requestSize, const QQuickImageProviderOptions &providerOptions,
                      QQuickImageProviderOptions::AutoTransform *appliedTransform = nullptr, int frame = 0,
                      qreal devicePixelRatio = 1.0)
{
    QImageReader imgio(dev);
    if (providerOptions.autoTransform() != QQuickImageProviderOptions::UsePluginDefaultTransform)
        imgio.setAutoTransform(providerOptions.autoTransform() == QQuickImageProviderOptions::ApplyTransform);
    else if (appliedTransform)
        *appliedTransform = imgio.autoTransform() ? QQuickImageProviderOptions::ApplyTransform : QQuickImageProviderOptions::DoNotApplyTransform;
 
    if (frame < imgio.imageCount())
        imgio.jumpToImage(frame);
 
    if (frameCount)
        *frameCount = imgio.imageCount();
 
    QSize scSize = QQuickImageProviderWithOptions::loadSize(imgio.size(), requestSize, imgio.format(), providerOptions, devicePixelRatio);
    if (scSize.isValid())
        imgio.setScaledSize(scSize);
    if (!requestRegion.isNull())
        imgio.setScaledClipRect(requestRegion);
    const QSize originalSize = imgio.size();
    qCDebug(lcImg) << url << "frame" << frame << "of" << imgio.imageCount()
                   << "requestRegion" << requestRegion << "QImageReader size" << originalSize << "-> scSize" << scSize;
 
    if (impsize)
        *impsize = originalSize;
 
    if (imgio.read(image)) {
        maybeRemoveAlpha(image);
        if (impsize && impsize->width() < 0)
            *impsize = image->size();
        if (providerOptions.targetColorSpace().isValid()) {
            if (image->colorSpace().isValid())
                image->convertToColorSpace(providerOptions.targetColorSpace());
            else
                image->setColorSpace(providerOptions.targetColorSpace());
        }
        return true;
    } else {
        if (errorString)
            *errorString = QQuickPixmap::tr("Error decoding: %1: %2").arg(url.toString())
                                .arg(imgio.errorString());
        return false;
    }
}
 
static QStringList fromLatin1List(const QList<QByteArray> &list)
{
    QStringList res;
    res.reserve(list.size());
    for (const QByteArray &item : list)
        res.append(QString::fromLatin1(item));
    return res;
}
 
class BackendSupport
{
public:
    BackendSupport()
    {
        delete QSGContext::createTextureFactoryFromImage(QImage());  // Force init of backend data
        hasOpenGL = QQuickWindow::sceneGraphBackend().isEmpty();     // i.e. default
        QList<QByteArray> list;
        if (hasOpenGL)
            list.append(QSGTextureReader::supportedFileFormats());
        list.append(QImageReader::supportedImageFormats());
        fileSuffixes = fromLatin1List(list);
    }
    bool hasOpenGL;
    QStringList fileSuffixes;
private:
    Q_DISABLE_COPY(BackendSupport)
};
Q_GLOBAL_STATIC(BackendSupport, backendSupport);
 
static QString existingImageFileForPath(const QString &localFile)
{
    // Do nothing if given filepath exists or already has a suffix
    QFileInfo fi(localFile);
    if (!fi.suffix().isEmpty() || fi.exists())
        return localFile;
 
    QString tryFile = localFile + QStringLiteral(".xxxx");
    const int suffixIdx = localFile.size() + 1;
    for (const QString &suffix : backendSupport()->fileSuffixes) {
        tryFile.replace(suffixIdx, 10, suffix);
        if (QFileInfo::exists(tryFile))
            return tryFile;
    }
    return localFile;
}
 
QQuickPixmapReader::QQuickPixmapReader(QQmlEngine *eng)
: QThread(eng), engine(eng)
#if QT_CONFIG(qml_network)
, accessManager(nullptr)
#endif
{
    Q_DETACH_THREAD_AFFINITY_MARKER(m_readerThreadAffinityMarker);
#if QT_CONFIG(quick_pixmap_cache_threaded_download)
    eventLoopQuitHack = new QObject;
    eventLoopQuitHack->moveToThread(this);
    QObject::connect(eventLoopQuitHack, &QObject::destroyed, this, &QThread::quit, Qt::DirectConnection);
    start(QThread::LowestPriority);
#else
    run(); // Call nonblocking run for ourselves.
#endif
}
 
QQuickPixmapReader::~QQuickPixmapReader()
{
    Q_ASSERT_CALLED_ON_VALID_THREAD(m_creatorThreadAffinityMarker);
 
    readerMutex.lock();
    readers.remove(engine);
    readerMutex.unlock();
 
    {
        PIXMAP_READER_LOCK();
        // manually cancel all outstanding jobs.
        for (QQuickPixmapReply *reply : std::as_const(jobs)) {
            if (reply->data && reply->data->reply == reply)
                reply->data->reply = nullptr;
            delete reply;
        }
        jobs.clear();
#if QT_CONFIG(qml_network)
        const auto cancelJob = [this](QQuickPixmapReply *reply) {
            if (reply->loading) {
                cancelledJobs.append(reply);
                reply->data = nullptr;
            }
        };
 
        for (auto *reply : std::as_const(networkJobs))
            cancelJob(reply);
 
        for (auto *reply : std::as_const(asyncResponses))
            cancelJob(reply);
#endif
#if !QT_CONFIG(quick_pixmap_cache_threaded_download)
    // In this case we won't be waiting, but we are on the correct thread already, so we can
    // perform housekeeping synchronously now.
    processJobs();
#else  // QT_CONFIG(quick_pixmap_cache_threaded_download) is true
    // Perform housekeeping on all the jobs cancelled above soon...
    if (readerThreadExecutionEnforcer())
        readerThreadExecutionEnforcer()->processJobsOnReaderThreadLater();
#endif
    }
 
#if QT_CONFIG(quick_pixmap_cache_threaded_download)
    // ... schedule stopping of this thread via the eventLoopQuitHack (processJobs scheduled above
    // will run first) ...
    eventLoopQuitHack->deleteLater();
    // ... and wait() for it all to finish, as the thread will only quit after eventLoopQuitHack
    // has been deleted.
    wait();
#endif
 
#if QT_CONFIG(qml_network)
    // While we've been waiting, the other thread may have added
    // more replies. No one will care about them anymore.
 
    auto deleteReply = [](QQuickPixmapReply *reply) {
        if (reply->data && reply->data->reply == reply)
            reply->data->reply = nullptr;
        delete reply;
    };
 
    for (QQuickPixmapReply *reply : std::as_const(networkJobs))
        deleteReply(reply);
 
    for (QQuickPixmapReply *reply : std::as_const(asyncResponses))
        deleteReply(reply);
 
    networkJobs.clear();
    asyncResponses.clear();
#endif
}
 
#if QT_CONFIG(qml_network)
void QQuickPixmapReader::networkRequestDone(QNetworkReply *reply)
{
    Q_ASSERT_CALLED_ON_VALID_THREAD(m_readerThreadAffinityMarker);
 
    QQuickPixmapReply *job = networkJobs.take(reply);
 
    if (job) {
        QImage image;
        QQuickPixmapReply::ReadError error = QQuickPixmapReply::NoError;
        QString errorString;
        QSize readSize;
        QQuickTextureFactory *factory = nullptr;
        if (reply->error()) {
            error = QQuickPixmapReply::Loading;
            errorString = reply->errorString();
        } else {
            QByteArray all = reply->readAll();
            QBuffer buff(&all);
            buff.open(QIODevice::ReadOnly);
            QSGTextureReader texReader(&buff, reply->url().fileName());
            if (backendSupport()->hasOpenGL && texReader.isTexture()) {
                factory = texReader.read();
                if (factory) {
                    readSize = factory->textureSize();
                } else {
                    error = QQuickPixmapReply::Decoding;
                    errorString = QQuickPixmap::tr("Error decoding: %1").arg(reply->url().toString());
                }
            } else {
                int frameCount;
                int const frame = job->data ? job->data->frame : 0;
                if (!readImage(reply->url(), &buff, &image, &errorString, &readSize, &frameCount,
                               job->requestRegion, job->requestSize, job->providerOptions, nullptr, frame))
                    error = QQuickPixmapReply::Decoding;
                else if (job->data)
                    job->data->frameCount = frameCount;
            }
        }
        // send completion event to the QQuickPixmapReply
        if (!factory)
            factory = QQuickTextureFactory::textureFactoryForImage(image);
 
        PIXMAP_READER_LOCK();
        if (!cancelledJobs.contains(job))
            job->postReply(error, errorString, readSize, factory);
    }
    reply->deleteLater();
 
    // kick off event loop again in case we have dropped below max request count
    readerThreadExecutionEnforcer()->processJobsOnReaderThreadLater();
}
#endif // qml_network
 
void QQuickPixmapReader::asyncResponseFinished(QQuickImageResponse *response)
{
    Q_ASSERT_CALLED_ON_VALID_THREAD(m_readerThreadAffinityMarker);
 
    QQuickPixmapReply *job = asyncResponses.take(response);
 
    if (job) {
        QQuickTextureFactory *t = nullptr;
        QQuickPixmapReply::ReadError error = QQuickPixmapReply::NoError;
        QString errorString;
        if (!response->errorString().isEmpty()) {
            error = QQuickPixmapReply::Loading;
            errorString = response->errorString();
        } else {
            t = response->textureFactory();
        }
 
        PIXMAP_READER_LOCK();
        if (!cancelledJobs.contains(job))
            job->postReply(error, errorString, t ? t->textureSize() : QSize(), t);
        else
            delete t;
    }
    response->deleteLater();
 
    // kick off event loop again in case we have dropped below max request count
    readerThreadExecutionEnforcer()->processJobsOnReaderThreadLater();
}
 
ReaderThreadExecutionEnforcer::ReaderThreadExecutionEnforcer(QQuickPixmapReader *i) : reader(i) { }
 
void ReaderThreadExecutionEnforcer::processJobsOnReaderThreadLater()
{
    QCoreApplication::postEvent(
            this, new QEvent(QEvent::Type(ReaderThreadExecutionEnforcer::ProcessJobs)));
}
 
bool ReaderThreadExecutionEnforcer::event(QEvent *e)
{
    switch (e->type()) {
    case QEvent::Type(ReaderThreadExecutionEnforcer::ProcessJobs):
        reader->processJobs();
        return true;
    default:
        return QObject::event(e);
    }
}
 
void ReaderThreadExecutionEnforcer::networkRequestDone()
{
#if QT_CONFIG(qml_network)
    QNetworkReply *reply = static_cast<QNetworkReply *>(sender());
    reader->networkRequestDone(reply);
#endif
}
 
void ReaderThreadExecutionEnforcer::asyncResponseFinished(QQuickImageResponse *response)
{
    reader->asyncResponseFinished(response);
}
 
void ReaderThreadExecutionEnforcer::asyncResponseFinished()
{
    QQuickImageResponse *response = static_cast<QQuickImageResponse *>(sender());
    asyncResponseFinished(response);
}
 
void QQuickPixmapReader::processJobs()
{
    Q_ASSERT_CALLED_ON_VALID_THREAD(m_readerThreadAffinityMarker);
 
    PIXMAP_READER_LOCK();
    while (true) {
        if (cancelledJobs.isEmpty() && jobs.isEmpty())
            return; // Nothing else to do
 
        // Clean cancelled jobs
        if (!cancelledJobs.isEmpty()) {
            for (int i = 0; i < cancelledJobs.size(); ++i) {
                QQuickPixmapReply *job = cancelledJobs.at(i);
#if QT_CONFIG(qml_network)
                QNetworkReply *reply = networkJobs.key(job, 0);
                if (reply) {
                    networkJobs.remove(reply);
                    if (reply->isRunning()) {
                        // cancel any jobs already started
                        reply->close();
                    }
                } else {
                    QQuickImageResponse *asyncResponse = asyncResponses.key(job);
                    if (asyncResponse) {
                        asyncResponses.remove(asyncResponse);
                        asyncResponse->cancel();
                    }
                }
                PIXMAP_PROFILE(pixmapStateChanged<QQuickProfiler::PixmapLoadingError>(job->url));
#endif
                // deleteLater, since not owned by this thread
                job->deleteLater();
            }
            cancelledJobs.clear();
        }
 
        if (!jobs.isEmpty()) {
            // Find a job we can use
            bool usableJob = false;
            for (int i = jobs.size() - 1; !usableJob && i >= 0; i--) {
                QQuickPixmapReply *job = jobs.at(i);
                const QUrl url = job->url;
                QString localFile;
                QQuickImageProvider::ImageType imageType = QQuickImageProvider::Invalid;
                QSharedPointer<QQuickImageProvider> provider;
 
                if (url.scheme() == QLatin1String("image")) {
                    QQmlEnginePrivate *enginePrivate = QQmlEnginePrivate::get(engine);
                    provider = enginePrivate->imageProvider(imageProviderId(url)).staticCast<QQuickImageProvider>();
                    if (provider)
                        imageType = provider->imageType();
 
                    usableJob = true;
                } else {
                    localFile = QQmlFile::urlToLocalFileOrQrc(url);
                    usableJob = !localFile.isEmpty()
#if QT_CONFIG(qml_network)
                            || networkJobs.size() < IMAGEREQUEST_MAX_NETWORK_REQUEST_COUNT
#endif
                            ;
                }
 
                if (usableJob) {
                    jobs.removeAt(i);
 
                    job->loading = true;
 
                    PIXMAP_PROFILE(pixmapStateChanged<QQuickProfiler::PixmapLoadingStarted>(url));
 
#if QT_CONFIG(quick_pixmap_cache_threaded_download)
                    locker.unlock();
                    auto relockMutexGuard = qScopeGuard(([&locker]() {
                        locker.relock();
                    }));
#endif
                    processJob(job, url, localFile, imageType, provider);
                }
            }
 
            if (!usableJob)
                return;
        }
    }
}
 
void QQuickPixmapReader::processJob(QQuickPixmapReply *runningJob, const QUrl &url, const QString &localFile,
                                    QQuickImageProvider::ImageType imageType, const QSharedPointer<QQuickImageProvider> &provider)
{
    Q_ASSERT_CALLED_ON_VALID_THREAD(m_readerThreadAffinityMarker);
 
    // fetch
    if (url.scheme() == QLatin1String("image")) {
        // Use QQuickImageProvider
        QSize readSize;
 
        if (imageType == QQuickImageProvider::Invalid) {
            QString errorStr = QQuickPixmap::tr("Invalid image provider: %1").arg(url.toString());
            PIXMAP_READER_LOCK();
            if (!cancelledJobs.contains(runningJob))
                runningJob->postReply(QQuickPixmapReply::Loading, errorStr, readSize, nullptr);
            return;
        }
 
        // This is safe because we ensure that provider does outlive providerV2 and it does not escape the function
        QQuickImageProviderWithOptions *providerV2 = QQuickImageProviderWithOptions::checkedCast(provider.get());
 
        switch (imageType) {
            case QQuickImageProvider::Invalid:
            {
                // Already handled
                break;
            }
 
            case QQuickImageProvider::Image:
            {
                QImage image;
                if (providerV2) {
                    image = providerV2->requestImage(imageId(url), &readSize, runningJob->requestSize, runningJob->providerOptions);
                } else {
                    image = provider->requestImage(imageId(url), &readSize, runningJob->requestSize);
                }
                QQuickPixmapReply::ReadError errorCode = QQuickPixmapReply::NoError;
                QString errorStr;
                if (image.isNull()) {
                    errorCode = QQuickPixmapReply::Loading;
                    errorStr = QQuickPixmap::tr("Failed to get image from provider: %1").arg(url.toString());
                }
                PIXMAP_READER_LOCK();
                if (!cancelledJobs.contains(runningJob)) {
                    runningJob->postReply(errorCode, errorStr, readSize,
                                          QQuickTextureFactory::textureFactoryForImage(image));
                }
                break;
            }
 
            case QQuickImageProvider::Pixmap:
            {
                QPixmap pixmap;
                if (providerV2) {
                    pixmap = providerV2->requestPixmap(imageId(url), &readSize, runningJob->requestSize, runningJob->providerOptions);
                } else {
                    pixmap = provider->requestPixmap(imageId(url), &readSize, runningJob->requestSize);
                }
                QQuickPixmapReply::ReadError errorCode = QQuickPixmapReply::NoError;
                QString errorStr;
                if (pixmap.isNull()) {
                    errorCode = QQuickPixmapReply::Loading;
                    errorStr = QQuickPixmap::tr("Failed to get image from provider: %1").arg(url.toString());
                }
 
                PIXMAP_READER_LOCK();
                if (!cancelledJobs.contains(runningJob)) {
                    runningJob->postReply(
                            errorCode, errorStr, readSize,
                            QQuickTextureFactory::textureFactoryForImage(pixmap.toImage()));
                }
                break;
            }
 
            case QQuickImageProvider::Texture:
            {
                QQuickTextureFactory *t;
                if (providerV2) {
                    t = providerV2->requestTexture(imageId(url), &readSize, runningJob->requestSize, runningJob->providerOptions);
                } else {
                    t = provider->requestTexture(imageId(url), &readSize, runningJob->requestSize);
                }
                QQuickPixmapReply::ReadError errorCode = QQuickPixmapReply::NoError;
                QString errorStr;
                if (!t) {
                    errorCode = QQuickPixmapReply::Loading;
                    errorStr = QQuickPixmap::tr("Failed to get texture from provider: %1").arg(url.toString());
                }
                PIXMAP_READER_LOCK();
                if (!cancelledJobs.contains(runningJob))
                    runningJob->postReply(errorCode, errorStr, readSize, t);
                else
                    delete t;
                break;
            }
 
            case QQuickImageProvider::ImageResponse:
            {
                QQuickImageResponse *response;
                if (providerV2) {
                    response = providerV2->requestImageResponse(imageId(url), runningJob->requestSize, runningJob->providerOptions);
                } else {
                    QQuickAsyncImageProvider *asyncProvider = static_cast<QQuickAsyncImageProvider*>(provider.get());
                    response = asyncProvider->requestImageResponse(imageId(url), runningJob->requestSize);
                }
 
                {
                    QObject::connect(response, &QQuickImageResponse::finished, readerThreadExecutionEnforcer(),
                                     qOverload<>(&ReaderThreadExecutionEnforcer::asyncResponseFinished));
                    // as the response object can outlive the provider QSharedPointer, we have to extend the pointee's lifetime by that of the response
                    // we do this by capturing a copy of the QSharedPointer in a lambda, and dropping it once the lambda has been called
                    auto provider_copy = provider; // capturing provider would capture it as a const reference, and copy capture with initializer is only available in C++14
                    QObject::connect(response, &QQuickImageResponse::destroyed, response, [provider_copy]() {
                        // provider_copy will be deleted when the connection gets deleted
                    });
                }
                // Might be that the async provider was so quick it emitted the signal before we
                // could connect to it.
                //
                // loadAcquire() synchronizes-with storeRelease() in QQuickImageResponsePrivate::_q_finished():
                if (static_cast<QQuickImageResponsePrivate*>(QObjectPrivate::get(response))->finished.loadAcquire()) {
                    QMetaObject::invokeMethod(readerThreadExecutionEnforcer(), "asyncResponseFinished",
                                              Qt::QueuedConnection,
                                              Q_ARG(QQuickImageResponse *, response));
                }
 
                asyncResponses.insert(response, runningJob);
                break;
            }
        }
 
    } else {
        if (!localFile.isEmpty()) {
            // Image is local - load/decode immediately
            QImage image;
            QQuickPixmapReply::ReadError errorCode = QQuickPixmapReply::NoError;
            QString errorStr;
            QSize readSize;
 
            if (runningJob->data && runningJob->data->specialDevice) {
                int frameCount;
                if (!readImage(url, runningJob->data->specialDevice, &image, &errorStr, &readSize, &frameCount,
                               runningJob->requestRegion, runningJob->requestSize,
                               runningJob->providerOptions, nullptr, runningJob->data->frame)) {
                    errorCode = QQuickPixmapReply::Loading;
                } else if (runningJob->data) {
                    runningJob->data->frameCount = frameCount;
                }
            } else {
                QFile f(existingImageFileForPath(localFile));
                if (f.open(QIODevice::ReadOnly)) {
                    QSGTextureReader texReader(&f, localFile);
                    if (backendSupport()->hasOpenGL && texReader.isTexture()) {
                        QQuickTextureFactory *factory = texReader.read();
                        if (factory) {
                            readSize = factory->textureSize();
                        } else {
                            errorStr = QQuickPixmap::tr("Error decoding: %1").arg(url.toString());
                            if (f.fileName() != localFile)
                                errorStr += QString::fromLatin1(" (%1)").arg(f.fileName());
                            errorCode = QQuickPixmapReply::Decoding;
                        }
                        PIXMAP_READER_LOCK();
                        if (!cancelledJobs.contains(runningJob))
                            runningJob->postReply(errorCode, errorStr, readSize, factory);
                        return;
                    } else {
                        int frameCount;
                        int const frame = runningJob->data ? runningJob->data->frame : 0;
                        if (!readImage(url, &f, &image, &errorStr, &readSize, &frameCount,
                                       runningJob->requestRegion, runningJob->requestSize,
                                       runningJob->providerOptions, nullptr, frame)) {
                            errorCode = QQuickPixmapReply::Loading;
                            if (f.fileName() != localFile)
                                errorStr += QString::fromLatin1(" (%1)").arg(f.fileName());
                        } else if (runningJob->data) {
                            runningJob->data->frameCount = frameCount;
                        }
                    }
                } else {
                    errorStr = QQuickPixmap::tr("Cannot open: %1").arg(url.toString());
                    errorCode = QQuickPixmapReply::Loading;
                }
            }
            PIXMAP_READER_LOCK();
            if (!cancelledJobs.contains(runningJob)) {
                runningJob->postReply(errorCode, errorStr, readSize,
                                      QQuickTextureFactory::textureFactoryForImage(image));
            }
        } else {
#if QT_CONFIG(qml_network)
            // Network resource
            QNetworkRequest req(url);
            req.setAttribute(QNetworkRequest::HttpPipeliningAllowedAttribute, true);
            QNetworkReply *reply = networkAccessManager()->get(req);
 
            QMetaObject::connect(reply, replyDownloadProgressMethodIndex, runningJob,
                                 downloadProgressMethodIndex);
            QMetaObject::connect(reply, replyFinishedMethodIndex, readerThreadExecutionEnforcer(),
                                 threadNetworkRequestDoneMethodIndex);
 
            networkJobs.insert(reply, runningJob);
#else
// Silently fail if compiled with no_network
#endif
        }
    }
}
 
QQuickPixmapReader *QQuickPixmapReader::instance(QQmlEngine *engine)
{
    // XXX NOTE: must be called within readerMutex locking.
    QQuickPixmapReader *reader = readers.value(engine);
    if (!reader) {
        reader = new QQuickPixmapReader(engine);
        readers.insert(engine, reader);
    }
 
    return reader;
}
 
QQuickPixmapReader *QQuickPixmapReader::existingInstance(QQmlEngine *engine)
{
    // XXX NOTE: must be called within readerMutex locking.
    return readers.value(engine, 0);
}
 
QQuickPixmapReply *QQuickPixmapReader::getImage(QQuickPixmapData *data)
{
    QQuickPixmapReply *reply = new QQuickPixmapReply(data);
    reply->engineForReader = engine;
    return reply;
}
 
void QQuickPixmapReader::startJob(QQuickPixmapReply *job)
{
    PIXMAP_READER_LOCK();
    jobs.append(job);
    if (readerThreadExecutionEnforcer())
        readerThreadExecutionEnforcer()->processJobsOnReaderThreadLater();
}
 
void QQuickPixmapReader::cancel(QQuickPixmapReply *reply)
{
    PIXMAP_READER_LOCK();
    if (reply->loading) {
        cancelledJobs.append(reply);
        reply->data = nullptr;
        // XXX
        if (readerThreadExecutionEnforcer())
            readerThreadExecutionEnforcer()->processJobsOnReaderThreadLater();
    } else {
        // If loading was started (reply removed from jobs) but the reply was never processed
        // (otherwise it would have deleted itself) we need to profile an error.
        if (jobs.removeAll(reply) == 0) {
            PIXMAP_PROFILE(pixmapStateChanged<QQuickProfiler::PixmapLoadingError>(reply->url));
        }
        delete reply;
    }
}
 
void QQuickPixmapReader::run()
{
    Q_ASSERT_CALLED_ON_VALID_THREAD(m_readerThreadAffinityMarker);
 
    if (replyDownloadProgressMethodIndex == -1) {
#if QT_CONFIG(qml_network)
        replyDownloadProgressMethodIndex =
                QMetaMethod::fromSignal(&QNetworkReply::downloadProgress).methodIndex();
        replyFinishedMethodIndex = QMetaMethod::fromSignal(&QNetworkReply::finished).methodIndex();
        const QMetaObject *ir = &ReaderThreadExecutionEnforcer::staticMetaObject;
        threadNetworkRequestDoneMethodIndex = ir->indexOfSlot("networkRequestDone()");
#endif
        downloadProgressMethodIndex =
                QMetaMethod::fromSignal(&QQuickPixmapReply::downloadProgress).methodIndex();
    }
 
#if QT_CONFIG(quick_pixmap_cache_threaded_download)
    const auto guard = qScopeGuard([this]() {
        // We need to delete the runLoopReaderThreadExecutionEnforcer from the same thread.
        PIXMAP_READER_LOCK();
        delete runLoopReaderThreadExecutionEnforcer;
        runLoopReaderThreadExecutionEnforcer = nullptr;
    });
 
    {
        PIXMAP_READER_LOCK();
        Q_ASSERT(!runLoopReaderThreadExecutionEnforcer);
        runLoopReaderThreadExecutionEnforcer = new ReaderThreadExecutionEnforcer(this);
    }
 
    processJobs();
    exec();
#else
    ownedReaderThreadExecutionEnforcer = std::make_unique<ReaderThreadExecutionEnforcer>(this);
    processJobs();
#endif
}
 
inline bool operator==(const QQuickPixmapKey &lhs, const QQuickPixmapKey &rhs)
{
    return *lhs.url == *rhs.url &&
           *lhs.region == *rhs.region &&
           *lhs.size == *rhs.size &&
            lhs.frame == rhs.frame &&
            lhs.options == rhs.options;
}
 
inline size_t qHash(const QQuickPixmapKey &key, size_t seed) noexcept
{
    return qHashMulti(seed, *key.url, *key.region, *key.size, key.frame, key.options.autoTransform());
}
 
#ifndef QT_NO_DEBUG_STREAM
inline QDebug operator<<(QDebug debug, const QQuickPixmapKey &key)
{
    QDebugStateSaver saver(debug);
    debug.nospace();
    if (!key.url) {
        debug << "QQuickPixmapKey(0)";
        return debug;
    }
 
    debug << "QQuickPixmapKey(" << key.url->toString() << " frame=" << key.frame;
    if (!key.region->isEmpty()) {
        debug << " region=";
        QtDebugUtils::formatQRect(debug, *key.region);
    }
    if (!key.size->isEmpty()) {
        debug << " size=";
        QtDebugUtils::formatQSize(debug, *key.size);
    }
    debug << ')';
    return debug;
}
#endif
 
QQuickPixmapCache *QQuickPixmapCache::instance()
{
    static QQuickPixmapCache self;
    return &self;
}
 
QQuickPixmapCache::~QQuickPixmapCache()
{
    destroyCache();
}
 
int QQuickPixmapCache::destroyCache()
{
    if (m_destroying)
        return -1;
 
    m_destroying = true;
 
    // Prevent unreferencePixmap() from assuming it needs to kick
    // off the cache expiry timer, as we're shrinking the cache
    // manually below after releasing all the pixmaps.
    m_timerId = -2;
 
    // unreference all (leaked) pixmaps
    int leakedPixmaps = 0;
    const auto cache = m_cache; // NOTE: intentional copy (QTBUG-65077); releasing items from the cache modifies m_cache.
    for (auto *pixmap : cache) {
        auto currRefCount = pixmap->refCount;
        if (currRefCount) {
            leakedPixmaps++;
            qCDebug(lcQsgLeak) << "leaked pixmap: refCount" << pixmap->refCount << pixmap->url << "frame" << pixmap->frame
                               << "size" << pixmap->requestSize << "region" << pixmap->requestRegion;
            while (currRefCount > 0) {
                pixmap->release(this);
                currRefCount--;
            }
        }
    }
 
    // free all unreferenced pixmaps
    while (m_lastUnreferencedPixmap)
        shrinkCache(20);
 
    qCDebug(lcQsgLeak, "Number of leaked pixmaps: %i", leakedPixmaps);
    return leakedPixmaps;
}
 
qsizetype QQuickPixmapCache::referencedCost() const
{
    qsizetype ret = 0;
    QMutexLocker locker(&m_cacheMutex);
    for (const auto *pixmap : std::as_const(m_cache)) {
        if (pixmap->refCount)
            ret += pixmap->cost();
    }
    return ret;
}
 
void QQuickPixmapCache::unreferencePixmap(QQuickPixmapData *data)
{
    Q_ASSERT(data->prevUnreferenced == nullptr);
    Q_ASSERT(data->prevUnreferencedPtr == nullptr);
    Q_ASSERT(data->nextUnreferenced == nullptr);
 
    data->nextUnreferenced = m_unreferencedPixmaps;
    data->prevUnreferencedPtr = &m_unreferencedPixmaps;
    if (!m_destroying) { // the texture factories may have been cleaned up already.
        m_unreferencedCost += data->cost();
        qCDebug(lcImg) << data->url << "had cost" << data->cost() << "of total unreferenced" << m_unreferencedCost;
    }
 
    m_unreferencedPixmaps = data;
    if (m_unreferencedPixmaps->nextUnreferenced) {
        m_unreferencedPixmaps->nextUnreferenced->prevUnreferenced = m_unreferencedPixmaps;
        m_unreferencedPixmaps->nextUnreferenced->prevUnreferencedPtr = &m_unreferencedPixmaps->nextUnreferenced;
    }
 
    if (!m_lastUnreferencedPixmap)
        m_lastUnreferencedPixmap = data;
 
    shrinkCache(-1); // Shrink the cache in case it has become larger than cache_limit
 
    if (m_timerId == -1 && m_unreferencedPixmaps
            && !m_destroying && !QCoreApplication::closingDown()) {
        m_timerId = startTimer(CACHE_EXPIRE_TIME * 1000);
    }
}
 
void QQuickPixmapCache::referencePixmap(QQuickPixmapData *data)
{
    Q_ASSERT(data->prevUnreferencedPtr);
 
    *data->prevUnreferencedPtr = data->nextUnreferenced;
    if (data->nextUnreferenced) {
        data->nextUnreferenced->prevUnreferencedPtr = data->prevUnreferencedPtr;
        data->nextUnreferenced->prevUnreferenced = data->prevUnreferenced;
    }
    if (m_lastUnreferencedPixmap == data)
        m_lastUnreferencedPixmap = data->prevUnreferenced;
 
    data->nextUnreferenced = nullptr;
    data->prevUnreferencedPtr = nullptr;
    data->prevUnreferenced = nullptr;
 
    m_unreferencedCost -= data->cost();
    qCDebug(lcImg) << data->url << "subtracts cost" << data->cost() << "of total" << m_unreferencedCost;
}
 
void QQuickPixmapCache::shrinkCache(int remove)
{
    qCDebug(lcImg) << "reduce unreferenced cost" << m_unreferencedCost << "to less than limit" << cache_limit;
    while ((remove > 0 || m_unreferencedCost > cache_limit) && m_lastUnreferencedPixmap) {
        QQuickPixmapData *data = m_lastUnreferencedPixmap;
        Q_ASSERT(data->nextUnreferenced == nullptr);
 
        *data->prevUnreferencedPtr = nullptr;
        m_lastUnreferencedPixmap = data->prevUnreferenced;
        data->prevUnreferencedPtr = nullptr;
        data->prevUnreferenced = nullptr;
 
        if (!m_destroying) {
            remove -= data->cost();
            m_unreferencedCost -= data->cost();
        }
        data->removeFromCache(this);
        delete data;
    }
}
 
void QQuickPixmapCache::timerEvent(QTimerEvent *)
{
    int removalCost = m_unreferencedCost / CACHE_REMOVAL_FRACTION;
 
    shrinkCache(removalCost);
 
    if (m_unreferencedPixmaps == nullptr) {
        killTimer(m_timerId);
        m_timerId = -1;
    }
}
 
void QQuickPixmapCache::purgeCache()
{
    shrinkCache(m_unreferencedCost);
}
 
void QQuickPixmap::purgeCache()
{
    QQuickPixmapCache::instance()->purgeCache();
}
 
QQuickPixmapReply::QQuickPixmapReply(QQuickPixmapData *d)
  : data(d), engineForReader(nullptr), requestRegion(d->requestRegion), requestSize(d->requestSize),
    url(d->url), loading(false), providerOptions(d->providerOptions)
{
    if (finishedMethodIndex == -1) {
        finishedMethodIndex = QMetaMethod::fromSignal(&QQuickPixmapReply::finished).methodIndex();
        downloadProgressMethodIndex =
                QMetaMethod::fromSignal(&QQuickPixmapReply::downloadProgress).methodIndex();
    }
}
 
QQuickPixmapReply::~QQuickPixmapReply()
{
    // note: this->data->reply must be set to zero if this->data->reply == this
    // but it must be done within mutex locking, to be guaranteed to be safe.
}
 
bool QQuickPixmapReply::event(QEvent *event)
{
    if (event->type() == QEvent::User) {
 
        if (data) {
            Event *de = static_cast<Event *>(event);
            data->pixmapStatus = (de->error == NoError) ? QQuickPixmap::Ready : QQuickPixmap::Error;
            if (data->pixmapStatus == QQuickPixmap::Ready) {
                data->textureFactory = de->textureFactory;
                de->textureFactory = nullptr;
                data->implicitSize = de->implicitSize;
                PIXMAP_PROFILE(pixmapLoadingFinished(data->url,
                        data->textureFactory != nullptr && data->textureFactory->textureSize().isValid() ?
                        data->textureFactory->textureSize() :
                        (data->requestSize.isValid() ? data->requestSize : data->implicitSize)));
            } else {
                PIXMAP_PROFILE(pixmapStateChanged<QQuickProfiler::PixmapLoadingError>(data->url));
                data->errorString = de->errorString;
                data->removeFromCache(); // We don't continue to cache error'd pixmaps
            }
 
            data->reply = nullptr;
            emit finished();
        } else {
            PIXMAP_PROFILE(pixmapStateChanged<QQuickProfiler::PixmapLoadingError>(url));
        }
 
        delete this;
        return true;
    } else {
        return QObject::event(event);
    }
}
 
int QQuickPixmapData::cost() const
{
    if (textureFactory)
        return textureFactory->textureByteCount();
    return 0;
}
 
void QQuickPixmapData::addref()
{
    ++refCount;
    PIXMAP_PROFILE(pixmapCountChanged<QQuickProfiler::PixmapReferenceCountChanged>(url, refCount));
    if (prevUnreferencedPtr)
        QQuickPixmapCache::instance()->referencePixmap(this);
}
 
void QQuickPixmapData::release(QQuickPixmapCache *store)
{
    Q_ASSERT(refCount > 0);
    --refCount;
    PIXMAP_PROFILE(pixmapCountChanged<QQuickProfiler::PixmapReferenceCountChanged>(url, refCount));
    if (refCount == 0) {
        if (reply) {
            QQuickPixmapReply *cancelReply = reply;
            reply->data = nullptr;
            reply = nullptr;
            QQuickPixmapReader::readerMutex.lock();
            QQuickPixmapReader *reader = QQuickPixmapReader::existingInstance(cancelReply->engineForReader);
            if (reader)
                reader->cancel(cancelReply);
            QQuickPixmapReader::readerMutex.unlock();
        }
 
        store = store ? store : QQuickPixmapCache::instance();
        if (pixmapStatus == QQuickPixmap::Ready
#ifdef Q_OS_WEBOS
                && storeToCache
#endif
                ) {
            if (inCache)
                store->unreferencePixmap(this);
            else
                delete this;
        } else {
            removeFromCache(store);
            delete this;
        }
    }
}
 
void QQuickPixmapData::addToCache()
{
    if (!inCache) {
        QQuickPixmapKey key = { &url, &requestRegion, &requestSize, frame, providerOptions };
        QMutexLocker locker(&QQuickPixmapCache::instance()->m_cacheMutex);
        if (lcImg().isDebugEnabled()) {
            qCDebug(lcImg) << "adding" << key << "to total" << QQuickPixmapCache::instance()->m_cache.size();
            for (auto it = QQuickPixmapCache::instance()->m_cache.keyBegin(); it != QQuickPixmapCache::instance()->m_cache.keyEnd(); ++it) {
                if (*(it->url) == url && it->frame == frame)
                    qDebug(lcImg) << "    similar pre-existing:" << *it;
            }
        }
        QQuickPixmapCache::instance()->m_cache.insert(key, this);
        inCache = true;
        PIXMAP_PROFILE(pixmapCountChanged<QQuickProfiler::PixmapCacheCountChanged>(
                url, QQuickPixmapCache::instance()->m_cache.size()));
    }
}
 
void QQuickPixmapData::removeFromCache(QQuickPixmapCache *store)
{
    if (inCache) {
        if (!store)
            store = QQuickPixmapCache::instance();
        QQuickPixmapKey key = { &url, &requestRegion, &requestSize, frame, providerOptions };
        QMutexLocker locker(&QQuickPixmapCache::instance()->m_cacheMutex);
        store->m_cache.remove(key);
        qCDebug(lcImg) << "removed" << key << implicitSize << "; total remaining" << QQuickPixmapCache::instance()->m_cache.size();
        inCache = false;
        PIXMAP_PROFILE(pixmapCountChanged<QQuickProfiler::PixmapCacheCountChanged>(
                url, store->m_cache.size()));
    }
}
 
static QQuickPixmapData* createPixmapDataSync(QQmlEngine *engine, const QUrl &url,
                                              const QRect &requestRegion, const QSize &requestSize,
                                              const QQuickImageProviderOptions &providerOptions, int frame, bool *ok,
                                              qreal devicePixelRatio)
{
    if (url.scheme() == QLatin1String("image")) {
        QSize readSize;
 
        QQuickImageProvider::ImageType imageType = QQuickImageProvider::Invalid;
        QQmlEnginePrivate *enginePrivate = QQmlEnginePrivate::get(engine);
        QSharedPointer<QQuickImageProvider> provider = enginePrivate->imageProvider(imageProviderId(url)).objectCast<QQuickImageProvider>();
        // it is safe to use get() as providerV2 does not escape and is outlived by provider
        QQuickImageProviderWithOptions *providerV2 = QQuickImageProviderWithOptions::checkedCast(provider.get());
        if (provider)
            imageType = provider->imageType();
 
        switch (imageType) {
            case QQuickImageProvider::Invalid:
                return new QQuickPixmapData(url, requestRegion, requestSize, providerOptions,
                    QQuickPixmap::tr("Invalid image provider: %1").arg(url.toString()));
            case QQuickImageProvider::Texture:
            {
                QQuickTextureFactory *texture = providerV2 ? providerV2->requestTexture(imageId(url), &readSize, requestSize, providerOptions)
                                                           : provider->requestTexture(imageId(url), &readSize, requestSize);
                if (texture) {
                    *ok = true;
                    return new QQuickPixmapData(url, texture, readSize, requestRegion, requestSize,
                                                providerOptions, QQuickImageProviderOptions::UsePluginDefaultTransform, frame);
                }
                break;
            }
 
            case QQuickImageProvider::Image:
            {
                QImage image = providerV2 ? providerV2->requestImage(imageId(url), &readSize, requestSize, providerOptions)
                                          : provider->requestImage(imageId(url), &readSize, requestSize);
                if (!image.isNull()) {
                    *ok = true;
                    return new QQuickPixmapData(url, QQuickTextureFactory::textureFactoryForImage(image),
                                                readSize, requestRegion, requestSize, providerOptions,
                                                QQuickImageProviderOptions::UsePluginDefaultTransform, frame);
                }
                break;
            }
            case QQuickImageProvider::Pixmap:
            {
                QPixmap pixmap = providerV2 ? providerV2->requestPixmap(imageId(url), &readSize, requestSize, providerOptions)
                                            : provider->requestPixmap(imageId(url), &readSize, requestSize);
                if (!pixmap.isNull()) {
                    *ok = true;
                    return new QQuickPixmapData(url, QQuickTextureFactory::textureFactoryForImage(pixmap.toImage()),
                                                readSize, requestRegion, requestSize, providerOptions,
                                                QQuickImageProviderOptions::UsePluginDefaultTransform, frame);
                }
                break;
            }
            case QQuickImageProvider::ImageResponse:
            {
                // Fall through, ImageResponse providers never get here
                Q_ASSERT(imageType != QQuickImageProvider::ImageResponse && "Sync call to ImageResponse provider");
            }
        }
 
        // provider has bad image type, or provider returned null image
        return new QQuickPixmapData(url, requestRegion, requestSize, providerOptions,
            QQuickPixmap::tr("Failed to get image from provider: %1").arg(url.toString()));
    }
 
    QString localFile = QQmlFile::urlToLocalFileOrQrc(url);
    if (localFile.isEmpty())
        return nullptr;
 
    QFile f(existingImageFileForPath(localFile));
    QSize readSize;
    QString errorString;
 
    if (f.open(QIODevice::ReadOnly)) {
        QSGTextureReader texReader(&f, localFile);
        if (backendSupport()->hasOpenGL && texReader.isTexture()) {
            QQuickTextureFactory *factory = texReader.read();
            if (factory) {
                *ok = true;
                return new QQuickPixmapData(url, factory, factory->textureSize(), requestRegion, requestSize,
                                            providerOptions, QQuickImageProviderOptions::UsePluginDefaultTransform, frame);
            } else {
                errorString = QQuickPixmap::tr("Error decoding: %1").arg(url.toString());
                if (f.fileName() != localFile)
                    errorString += QString::fromLatin1(" (%1)").arg(f.fileName());
            }
        } else {
            QImage image;
            QQuickImageProviderOptions::AutoTransform appliedTransform = providerOptions.autoTransform();
            int frameCount;
            if (readImage(url, &f, &image, &errorString, &readSize, &frameCount, requestRegion, requestSize,
                          providerOptions, &appliedTransform, frame, devicePixelRatio)) {
                *ok = true;
                return new QQuickPixmapData(url, QQuickTextureFactory::textureFactoryForImage(image), readSize, requestRegion, requestSize,
                                            providerOptions, appliedTransform, frame, frameCount);
            } else if (f.fileName() != localFile) {
                errorString += QString::fromLatin1(" (%1)").arg(f.fileName());
            }
        }
    } else {
        errorString = QQuickPixmap::tr("Cannot open: %1").arg(url.toString());
    }
    return new QQuickPixmapData(url, requestRegion, requestSize, providerOptions, errorString);
}
 
 
struct QQuickPixmapNull {
    QUrl url;
    QRect region;
    QSize size;
};
Q_GLOBAL_STATIC(QQuickPixmapNull, nullPixmap);
 
QQuickPixmap::QQuickPixmap()
: d(nullptr)
{
}
 
QQuickPixmap::QQuickPixmap(QQmlEngine *engine, const QUrl &url)
: d(nullptr)
{
    load(engine, url);
}
 
QQuickPixmap::QQuickPixmap(QQmlEngine *engine, const QUrl &url, Options options)
: d(nullptr)
{
    load(engine, url, options);
}
 
QQuickPixmap::QQuickPixmap(QQmlEngine *engine, const QUrl &url, const QRect &region, const QSize &size)
: d(nullptr)
{
    load(engine, url, region, size);
}
 
QQuickPixmap::QQuickPixmap(const QUrl &url, const QImage &image)
{
    d = new QQuickPixmapData(url, new QQuickDefaultTextureFactory(image), image.size(), QRect(), QSize(),
                             QQuickImageProviderOptions(), QQuickImageProviderOptions::UsePluginDefaultTransform);
    d->addToCache();
}
 
QQuickPixmap::~QQuickPixmap()
{
    if (d) {
        d->release();
        d = nullptr;
    }
}
 
bool QQuickPixmap::isNull() const
{
    return d == nullptr;
}
 
bool QQuickPixmap::isReady() const
{
    return status() == Ready;
}
 
bool QQuickPixmap::isError() const
{
    return status() == Error;
}
 
bool QQuickPixmap::isLoading() const
{
    return status() == Loading;
}
 
QString QQuickPixmap::error() const
{
    if (d)
        return d->errorString;
    else
        return QString();
}
 
QQuickPixmap::Status QQuickPixmap::status() const
{
    if (d)
        return d->pixmapStatus;
    else
        return Null;
}
 
const QUrl &QQuickPixmap::url() const
{
    if (d)
        return d->url;
    else
        return nullPixmap()->url;
}
 
const QSize &QQuickPixmap::implicitSize() const
{
    if (d)
        return d->implicitSize;
    else
        return nullPixmap()->size;
}
 
const QSize &QQuickPixmap::requestSize() const
{
    if (d)
        return d->requestSize;
    else
        return nullPixmap()->size;
}
 
const QRect &QQuickPixmap::requestRegion() const
{
    if (d)
        return d->requestRegion;
    else
        return nullPixmap()->region;
}
 
QQuickImageProviderOptions::AutoTransform QQuickPixmap::autoTransform() const
{
    if (d)
        return d->appliedTransform;
    else
        return QQuickImageProviderOptions::UsePluginDefaultTransform;
}
 
int QQuickPixmap::frameCount() const
{
    if (d)
        return d->frameCount;
    return 0;
}
 
QQuickTextureFactory *QQuickPixmap::textureFactory() const
{
    if (d)
        return d->textureFactory;
 
    return nullptr;
}
 
QImage QQuickPixmap::image() const
{
    if (d && d->textureFactory)
        return d->textureFactory->image();
    return QImage();
}
 
void QQuickPixmap::setImage(const QImage &p)
{
    clear();
 
    if (!p.isNull()) {
        if (d)
            d->release();
        d = new QQuickPixmapData(QQuickTextureFactory::textureFactoryForImage(p));
    }
}
 
void QQuickPixmap::setPixmap(const QQuickPixmap &other)
{
    if (d == other.d)
        return;
    clear();
 
    if (other.d) {
        if (d)
            d->release();
        d = other.d;
        d->addref();
    }
}
 
int QQuickPixmap::width() const
{
    if (d && d->textureFactory)
        return d->textureFactory->textureSize().width();
    else
        return 0;
}
 
int QQuickPixmap::height() const
{
    if (d && d->textureFactory)
        return d->textureFactory->textureSize().height();
    else
        return 0;
}
 
QRect QQuickPixmap::rect() const
{
    if (d && d->textureFactory)
        return QRect(QPoint(), d->textureFactory->textureSize());
    else
        return QRect();
}
 
void QQuickPixmap::load(QQmlEngine *engine, const QUrl &url)
{
    load(engine, url, QRect(), QSize(), QQuickPixmap::Cache);
}
 
void QQuickPixmap::load(QQmlEngine *engine, const QUrl &url, QQuickPixmap::Options options)
{
    load(engine, url, QRect(), QSize(), options);
}
 
void QQuickPixmap::load(QQmlEngine *engine, const QUrl &url, const QRect &requestRegion, const QSize &requestSize)
{
    load(engine, url, requestRegion, requestSize, QQuickPixmap::Cache);
}
 
void QQuickPixmap::load(QQmlEngine *engine, const QUrl &url, const QRect &requestRegion, const QSize &requestSize, QQuickPixmap::Options options)
{
    load(engine, url, requestRegion, requestSize, options, QQuickImageProviderOptions());
}
 
void QQuickPixmap::load(QQmlEngine *engine, const QUrl &url, const QRect &requestRegion, const QSize &requestSize,
                        QQuickPixmap::Options options, const QQuickImageProviderOptions &providerOptions, int frame, int frameCount,
                        qreal devicePixelRatio)
{
    if (d) {
        d->release();
        d = nullptr;
    }
 
    QQuickPixmapKey key = { &url, &requestRegion, &requestSize, frame, providerOptions };
    QQuickPixmapCache *store = QQuickPixmapCache::instance();
 
    QMutexLocker locker(&QQuickPixmapCache::instance()->m_cacheMutex);
    QHash<QQuickPixmapKey, QQuickPixmapData *>::Iterator iter = store->m_cache.end();
 
#ifdef Q_OS_WEBOS
    QQuickPixmap::Options orgOptions = options;
    // In webOS, we suppose that cache is always enabled to share image instances along its source.
    // So, original option(orgOptions) for cache only decides whether to store the instances when it's unreferenced.
    options |= QQuickPixmap::Cache;
#endif
 
    // If Cache is disabled, the pixmap will always be loaded, even if there is an existing
    // cached version. Unless it's an itemgrabber url, since the cache is used to pass
    // the result between QQuickItemGrabResult and QQuickImage.
    if (url.scheme() == itemGrabberScheme) {
        QRect dummyRegion;
        QSize dummySize;
        if (requestSize != dummySize)
            qWarning() << "Ignoring sourceSize request for image url that came from grabToImage. Use the targetSize parameter of the grabToImage() function instead.";
        const QQuickPixmapKey grabberKey = { &url, &dummyRegion, &dummySize, 0, QQuickImageProviderOptions() };
        iter = store->m_cache.find(grabberKey);
    } else if (options & QQuickPixmap::Cache)
        iter = store->m_cache.find(key);
 
    if (iter == store->m_cache.end()) {
        locker.unlock();
        if (url.scheme() == QLatin1String("image")) {
            QQmlEnginePrivate *enginePrivate = QQmlEnginePrivate::get(engine);
            if (auto provider = enginePrivate->imageProvider(imageProviderId(url)).staticCast<QQuickImageProvider>()) {
                const bool threadedPixmaps = QGuiApplicationPrivate::platformIntegration()->hasCapability(QPlatformIntegration::ThreadedPixmaps);
                if (!threadedPixmaps && provider->imageType() == QQuickImageProvider::Pixmap) {
                    // pixmaps can only be loaded synchronously
                    options &= ~QQuickPixmap::Asynchronous;
                } else if (provider->flags() & QQuickImageProvider::ForceAsynchronousImageLoading) {
                    options |= QQuickPixmap::Asynchronous;
                }
            }
        }
 
        if (!(options & QQuickPixmap::Asynchronous)) {
            bool ok = false;
            PIXMAP_PROFILE(pixmapStateChanged<QQuickProfiler::PixmapLoadingStarted>(url));
            d = createPixmapDataSync(engine, url, requestRegion, requestSize, providerOptions, frame, &ok, devicePixelRatio);
            if (ok) {
                PIXMAP_PROFILE(pixmapLoadingFinished(url, QSize(width(), height())));
                if (options & QQuickPixmap::Cache)
                    d->addToCache();
#ifdef Q_OS_WEBOS
                d->storeToCache = orgOptions & QQuickPixmap::Cache;
#endif
                return;
            }
            if (d) { // loadable, but encountered error while loading
                PIXMAP_PROFILE(pixmapStateChanged<QQuickProfiler::PixmapLoadingError>(url));
                return;
            }
        }
 
        if (!engine)
            return;
 
 
        d = new QQuickPixmapData(url, requestRegion, requestSize, providerOptions,
                                 QQuickImageProviderOptions::UsePluginDefaultTransform, frame, frameCount);
        if (options & QQuickPixmap::Cache)
            d->addToCache();
#ifdef Q_OS_WEBOS
        d->storeToCache = orgOptions & QQuickPixmap::Cache;
#endif
 
        QQuickPixmapReader::readerMutex.lock();
        QQuickPixmapReader *reader = QQuickPixmapReader::instance(engine);
        d->reply = reader->getImage(d);
        reader->startJob(d->reply);
        QQuickPixmapReader::readerMutex.unlock();
    } else {
        d = *iter;
        d->addref();
        qCDebug(lcImg) << "loaded from cache" << url << "frame" << frame;
    }
}
 
void QQuickPixmap::loadImageFromDevice(QQmlEngine *engine, QIODevice *device, const QUrl &url,
                                       const QRect &requestRegion, const QSize &requestSize,
                                       const QQuickImageProviderOptions &providerOptions, int frame, int frameCount)
{
    auto oldD = d;
    QQuickPixmapKey key = { &url, &requestRegion, &requestSize, frame, providerOptions };
    QQuickPixmapCache *store = QQuickPixmapCache::instance();
    QHash<QQuickPixmapKey, QQuickPixmapData *>::Iterator iter = store->m_cache.end();
    QMutexLocker locker(&store->m_cacheMutex);
    iter = store->m_cache.find(key);
    if (iter == store->m_cache.end()) {
        if (!engine)
            return;
 
        locker.unlock();
        d = new QQuickPixmapData(url, requestRegion, requestSize, providerOptions,
                                 QQuickImageProviderOptions::UsePluginDefaultTransform, frame, frameCount);
        d->specialDevice = device;
        d->addToCache();
 
        QQuickPixmapReader::readerMutex.lock();
        QQuickPixmapReader *reader = QQuickPixmapReader::instance(engine);
        d->reply = reader->getImage(d);
        if (oldD) {
            QObject::connect(d->reply, &QQuickPixmapReply::destroyed, store, [oldD]() {
                oldD->release();
            }, Qt::QueuedConnection);
        }
        reader->startJob(d->reply);
        QQuickPixmapReader::readerMutex.unlock();
    } else {
        d = *iter;
        d->addref();
        qCDebug(lcImg) << "loaded from cache" << url << "frame" << frame << "refCount" << d->refCount;
        locker.unlock();
        if (oldD)
            oldD->release();
    }
}
 
void QQuickPixmap::clear()
{
    if (d) {
        d->release();
        d = nullptr;
    }
}
 
void QQuickPixmap::clear(QObject *obj)
{
    if (d) {
        if (d->reply)
            QObject::disconnect(d->reply, nullptr, obj, nullptr);
        d->release();
        d = nullptr;
    }
}
 
bool QQuickPixmap::isCached(const QUrl &url, const QRect &requestRegion, const QSize &requestSize,
                            const int frame, const QQuickImageProviderOptions &options)
{
    QQuickPixmapKey key = { &url, &requestRegion, &requestSize, frame, options };
    QQuickPixmapCache *store = QQuickPixmapCache::instance();
 
    return store->m_cache.contains(key);
}
 
bool QQuickPixmap::isScalableImageFormat(const QUrl &url)
{
    if (url.scheme() == "image"_L1)
        return true;
 
    const QString stringUrl = url.path(QUrl::PrettyDecoded);
    return stringUrl.endsWith("svg"_L1)
            || stringUrl.endsWith("svgz"_L1)
            || stringUrl.endsWith("pdf"_L1);
}
 
bool QQuickPixmap::connectFinished(QObject *object, const char *method)
{
    if (!d || !d->reply) {
        qWarning("QQuickPixmap: connectFinished() called when not loading.");
        return false;
    }
 
    return QObject::connect(d->reply, SIGNAL(finished()), object, method);
}
 
bool QQuickPixmap::connectFinished(QObject *object, int method)
{
    if (!d || !d->reply) {
        qWarning("QQuickPixmap: connectFinished() called when not loading.");
        return false;
    }
 
    return QMetaObject::connect(d->reply, QQuickPixmapReply::finishedMethodIndex, object, method);
}
 
bool QQuickPixmap::connectDownloadProgress(QObject *object, const char *method)
{
    if (!d || !d->reply) {
        qWarning("QQuickPixmap: connectDownloadProgress() called when not loading.");
        return false;
    }
 
    return QObject::connect(d->reply, SIGNAL(downloadProgress(qint64,qint64)), object,
                            method);
}
 
bool QQuickPixmap::connectDownloadProgress(QObject *object, int method)
{
    if (!d || !d->reply) {
        qWarning("QQuickPixmap: connectDownloadProgress() called when not loading.");
        return false;
    }
 
    return QMetaObject::connect(d->reply, QQuickPixmapReply::downloadProgressMethodIndex, object,
                                method);
}
 
QColorSpace QQuickPixmap::colorSpace() const
{
    if (!d || !d->textureFactory)
        return QColorSpace();
    return d->textureFactory->image().colorSpace();
}
 
QT_END_NAMESPACE
 
#include <qquickpixmapcache.moc>
 
#include "moc_qquickpixmapcache_p.cpp"