qicon.cpp

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// Copyright (C) 2020 The Qt Company Ltd.
// Copyright (C) 2015 Olivier Goffart <ogoffart@woboq.com>
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
#include "qicon.h"
#include "qicon_p.h"
#include "qiconengine.h"
#include "qiconengineplugin.h"
#include "qimagereader.h"
#include "private/qfactoryloader_p.h"
#include "private/qiconloader_p.h"
#include "qpainter.h"
#include "qfileinfo.h"
#if QT_CONFIG(mimetype)
#include <qmimedatabase.h>
#include <qmimetype.h>
#endif
#include "qpixmapcache.h"
#include "qvariant.h"
#include "qcache.h"
#include "qdebug.h"
#include "qdir.h"
#include "qpalette.h"
#include "qmath.h"
 
#include "private/qhexstring_p.h"
#include "private/qguiapplication_p.h"
#include "private/qoffsetstringarray_p.h"
#include "qpa/qplatformtheme.h"
 
#ifndef QT_NO_ICON
QT_BEGIN_NAMESPACE
 
using namespace Qt::StringLiterals;
 
static int nextSerialNumCounter()
{
    Q_CONSTINIT static QBasicAtomicInt serial = Q_BASIC_ATOMIC_INITIALIZER(0);
    return 1 + serial.fetchAndAddRelaxed(1);
}
 
static void qt_cleanup_icon_cache();
namespace {
    struct IconCache : public QCache<QString, QIcon>
    {
        IconCache()
        {
            // ### note: won't readd if QApplication is re-created!
            qAddPostRoutine(qt_cleanup_icon_cache);
        }
    };
}
 
Q_GLOBAL_STATIC(IconCache, qtIconCache)
 
static void qt_cleanup_icon_cache()
{
    qtIconCache()->clear();
}
 
QIconPrivate::QIconPrivate(QIconEngine *e)
    : engine(e), ref(1),
      serialNum(nextSerialNumCounter()),
    detach_no(0),
    is_mask(false)
{
}
 
void QIconPrivate::clearIconCache()
{
    qt_cleanup_icon_cache();
}
 
qreal QIconPrivate::pixmapDevicePixelRatio(qreal displayDevicePixelRatio, const QSize &requestedSize, const QSize &actualSize)
{
    QSize targetSize = requestedSize * displayDevicePixelRatio;
    if ((actualSize.width() == targetSize.width() && actualSize.height() <= targetSize.height()) ||
        (actualSize.width() <= targetSize.width() && actualSize.height() == targetSize.height())) {
        // Correctly scaled for dpr, just having different aspect ratio
        return displayDevicePixelRatio;
    }
    qreal scale = 0.5 * (qreal(actualSize.width()) / qreal(targetSize.width()) +
                         qreal(actualSize.height() / qreal(targetSize.height())));
    return qMax(qreal(1.0), displayDevicePixelRatio *scale);
}
 
QPixmapIconEngine::QPixmapIconEngine()
{
}
 
QPixmapIconEngine::QPixmapIconEngine(const QPixmapIconEngine &other)
    : QIconEngine(other), pixmaps(other.pixmaps)
{
}
 
QPixmapIconEngine::~QPixmapIconEngine()
{
}
 
void QPixmapIconEngine::paint(QPainter *painter, const QRect &rect, QIcon::Mode mode, QIcon::State state)
{
    auto paintDevice = painter->device();
    qreal dpr = paintDevice ? paintDevice->devicePixelRatio() : qApp->devicePixelRatio();
    const QSize pixmapSize = rect.size() * dpr;
    QPixmap px = scaledPixmap(pixmapSize, mode, state, dpr);
    painter->drawPixmap(rect, px);
}
 
static inline int area(const QSize &s) { return s.width() * s.height(); }
 
// Returns the smallest of the two that is still larger than or equal to size.
// Pixmaps at the correct scale are preferred, pixmaps at lower scale are
// used as fallbacks. We assume that the pixmap set is complete, in the sense
// that no 2x pixmap is going to be a better match than a 3x pixmap for the the
// target scale of 3 (It's OK if 3x pixmaps are missing - we'll fall back to
// the 2x pixmaps then.)
static QPixmapIconEngineEntry *bestSizeScaleMatch(const QSize &size, qreal scale, QPixmapIconEngineEntry *pa, QPixmapIconEngineEntry *pb)
{
    const auto scaleA = pa->pixmap.devicePixelRatio();
    const auto scaleB = pb->pixmap.devicePixelRatio();
    // scale: we can only differentiate on scale if the scale differs
    if (scaleA != scaleB) {
 
        // Score the pixmaps: 0 is an exact scale match, positive
        // scores have more detail than requested, negative scores
        // have less detail than requested.
        qreal ascore = scaleA - scale;
        qreal bscore = scaleB - scale;
 
        // always prefer positive scores to prevent upscaling
        if ((ascore < 0) != (bscore < 0))
            return bscore < 0 ? pa : pb;
        // Take the one closest to 0
        return (qAbs(ascore) < qAbs(bscore)) ? pa : pb;
    }
 
    int s = area(size);
    if (pa->size == QSize() && pa->pixmap.isNull()) {
        pa->pixmap = QPixmap(pa->fileName);
        pa->size = pa->pixmap.size();
    }
    int a = area(pa->size);
    if (pb->size == QSize() && pb->pixmap.isNull()) {
        pb->pixmap = QPixmap(pb->fileName);
        pb->size = pb->pixmap.size();
    }
    int b = area(pb->size);
    int res = a;
    if (qMin(a,b) >= s)
        res = qMin(a,b);
    else
        res = qMax(a,b);
    if (res == a)
        return pa;
    return pb;
}
 
QPixmapIconEngineEntry *QPixmapIconEngine::tryMatch(const QSize &size, qreal scale, QIcon::Mode mode, QIcon::State state)
{
    QPixmapIconEngineEntry *pe = nullptr;
    for (auto &entry : pixmaps) {
        if (entry.mode == mode && entry.state == state) {
            if (pe)
                pe = bestSizeScaleMatch(size, scale, &entry, pe);
            else
                pe = &entry;
        }
    }
    return pe;
}
 
 
QPixmapIconEngineEntry *QPixmapIconEngine::bestMatch(const QSize &size, qreal scale, QIcon::Mode mode, QIcon::State state, bool sizeOnly)
{
    QPixmapIconEngineEntry *pe = tryMatch(size, scale, mode, state);
    while (!pe){
        QIcon::State oppositeState = (state == QIcon::On) ? QIcon::Off : QIcon::On;
        if (mode == QIcon::Disabled || mode == QIcon::Selected) {
            QIcon::Mode oppositeMode = (mode == QIcon::Disabled) ? QIcon::Selected : QIcon::Disabled;
            if ((pe = tryMatch(size, scale, QIcon::Normal, state)))
                break;
            if ((pe = tryMatch(size, scale, QIcon::Active, state)))
                break;
            if ((pe = tryMatch(size, scale, mode, oppositeState)))
                break;
            if ((pe = tryMatch(size, scale, QIcon::Normal, oppositeState)))
                break;
            if ((pe = tryMatch(size, scale, QIcon::Active, oppositeState)))
                break;
            if ((pe = tryMatch(size, scale, oppositeMode, state)))
                break;
            if ((pe = tryMatch(size, scale, oppositeMode, oppositeState)))
                break;
        } else {
            QIcon::Mode oppositeMode = (mode == QIcon::Normal) ? QIcon::Active : QIcon::Normal;
            if ((pe = tryMatch(size, scale, oppositeMode, state)))
                break;
            if ((pe = tryMatch(size, scale, mode, oppositeState)))
                break;
            if ((pe = tryMatch(size, scale, oppositeMode, oppositeState)))
                break;
            if ((pe = tryMatch(size, scale, QIcon::Disabled, state)))
                break;
            if ((pe = tryMatch(size, scale, QIcon::Selected, state)))
                break;
            if ((pe = tryMatch(size, scale, QIcon::Disabled, oppositeState)))
                break;
            if ((pe = tryMatch(size, scale, QIcon::Selected, oppositeState)))
                break;
        }
 
        if (!pe)
            return pe;
    }
 
    if (sizeOnly ? (pe->size.isNull() || !pe->size.isValid()) : pe->pixmap.isNull()) {
        pe->pixmap = QPixmap(pe->fileName);
        if (!pe->pixmap.isNull())
            pe->size = pe->pixmap.size();
    }
 
    return pe;
}
 
QPixmap QPixmapIconEngine::pixmap(const QSize &size, QIcon::Mode mode, QIcon::State state)
{
    return scaledPixmap(size, mode, state, 1.0);
}
 
QPixmap QPixmapIconEngine::scaledPixmap(const QSize &size, QIcon::Mode mode, QIcon::State state, qreal scale)
{
 
    QPixmap pm;
    QPixmapIconEngineEntry *pe = bestMatch(size, scale, mode, state, false);
    if (pe)
        pm = pe->pixmap;
 
    if (pm.isNull()) {
        auto idx = pixmaps.size();
        while (--idx >= 0) {
            if (pe == &pixmaps.at(idx)) {
                pixmaps.remove(idx);
                break;
            }
        }
        if (pixmaps.isEmpty())
            return pm;
        else
            return pixmap(size, mode, state);
    }
 
    QSize actualSize = pm.size();
    if (!actualSize.isNull() && (actualSize.width() > size.width() || actualSize.height() > size.height()))
        actualSize.scale(size, Qt::KeepAspectRatio);
 
    QString key = "qt_"_L1
                  % HexString<quint64>(pm.cacheKey())
                  % HexString<uint>(pe ? pe->mode : QIcon::Normal)
                  % HexString<quint64>(QGuiApplication::palette().cacheKey())
                  % HexString<uint>(actualSize.width())
                  % HexString<uint>(actualSize.height());
 
    if (mode == QIcon::Active) {
        if (QPixmapCache::find(key % HexString<uint>(mode), &pm))
            return pm; // horray
        if (QPixmapCache::find(key % HexString<uint>(QIcon::Normal), &pm)) {
            QPixmap active = pm;
            if (QGuiApplication *guiApp = qobject_cast<QGuiApplication *>(qApp))
                active = static_cast<QGuiApplicationPrivate*>(QObjectPrivate::get(guiApp))->applyQIconStyleHelper(QIcon::Active, pm);
            if (pm.cacheKey() == active.cacheKey())
                return pm;
        }
    }
 
    if (!QPixmapCache::find(key % HexString<uint>(mode), &pm)) {
        if (pm.size() != actualSize)
            pm = pm.scaled(actualSize, Qt::IgnoreAspectRatio, Qt::SmoothTransformation);
        if (pe->mode != mode && mode != QIcon::Normal) {
            QPixmap generated = pm;
            if (QGuiApplication *guiApp = qobject_cast<QGuiApplication *>(qApp))
                generated = static_cast<QGuiApplicationPrivate*>(QObjectPrivate::get(guiApp))->applyQIconStyleHelper(mode, pm);
            if (!generated.isNull())
                pm = generated;
        }
        QPixmapCache::insert(key % HexString<uint>(mode), pm);
    }
    return pm;
}
 
QSize QPixmapIconEngine::actualSize(const QSize &size, QIcon::Mode mode, QIcon::State state)
{
    QSize actualSize;
 
    // The returned actual size is the size in device independent pixels,
    // so we limit the search to scale 1 and assume that e.g. @2x versions
    // does not proviode extra actual sizes not also provided by the 1x versions.
    qreal scale = 1;
 
    if (QPixmapIconEngineEntry *pe = bestMatch(size, scale, mode, state, true))
        actualSize = pe->size;
 
    if (actualSize.isNull())
        return actualSize;
 
    if (!actualSize.isNull() && (actualSize.width() > size.width() || actualSize.height() > size.height()))
        actualSize.scale(size, Qt::KeepAspectRatio);
    return actualSize;
}
 
QList<QSize> QPixmapIconEngine::availableSizes(QIcon::Mode mode, QIcon::State state)
{
    QList<QSize> sizes;
    for (QPixmapIconEngineEntry &pe : pixmaps) {
        if (pe.mode != mode || pe.state != state)
            continue;
        if (pe.size.isEmpty() && pe.pixmap.isNull()) {
            pe.pixmap = QPixmap(pe.fileName);
            pe.size = pe.pixmap.size();
        }
        if (!pe.size.isEmpty() && !sizes.contains(pe.size))
            sizes.push_back(pe.size);
    }
    return sizes;
}
 
void QPixmapIconEngine::addPixmap(const QPixmap &pixmap, QIcon::Mode mode, QIcon::State state)
{
    if (!pixmap.isNull()) {
        QPixmapIconEngineEntry *pe = tryMatch(pixmap.size(), pixmap.devicePixelRatio(), mode, state);
        if (pe && pe->size == pixmap.size() && pe->pixmap.devicePixelRatio() == pixmap.devicePixelRatio()) {
            pe->pixmap = pixmap;
            pe->fileName.clear();
        } else {
            pixmaps += QPixmapIconEngineEntry(pixmap, mode, state);
        }
    }
}
 
// Read out original image depth as set by ICOReader
static inline int origIcoDepth(const QImage &image)
{
    const QString s = image.text(QStringLiteral("_q_icoOrigDepth"));
    return s.isEmpty() ? 32 : s.toInt();
}
 
static inline int findBySize(const QList<QImage> &images, const QSize &size)
{
    for (qsizetype i = 0; i < images.size(); ++i) {
        if (images.at(i).size() == size)
            return i;
    }
    return -1;
}
 
// Convenience class providing a bool read() function.
namespace {
class ImageReader
{
public:
    ImageReader(const QString &fileName) : m_reader(fileName), m_atEnd(false) {}
 
    QByteArray format() const { return m_reader.format(); }
 
    bool read(QImage *image)
    {
        if (m_atEnd)
            return false;
        *image = m_reader.read();
        if (!image->size().isValid()) {
            m_atEnd = true;
            return false;
        }
        m_atEnd = !m_reader.jumpToNextImage();
        return true;
    }
 
private:
    QImageReader m_reader;
    bool m_atEnd;
};
} // namespace
 
void QPixmapIconEngine::addFile(const QString &fileName, const QSize &size, QIcon::Mode mode, QIcon::State state)
{
    if (fileName.isEmpty())
        return;
    const QString abs = fileName.startsWith(u':') ? fileName : QFileInfo(fileName).absoluteFilePath();
    const bool ignoreSize = !size.isValid();
    ImageReader imageReader(abs);
    const QByteArray format = imageReader.format();
    if (format.isEmpty()) // Device failed to open or unsupported format.
        return;
    QImage image;
    if (format != "ico") {
        if (ignoreSize) { // No size specified: Add all images.
            while (imageReader.read(&image))
                pixmaps += QPixmapIconEngineEntry(abs, image, mode, state);
        } else {
            // Try to match size. If that fails, add a placeholder with the filename and empty pixmap for the size.
            while (imageReader.read(&image) && image.size() != size) {}
            pixmaps += image.size() == size ?
                QPixmapIconEngineEntry(abs, image, mode, state) : QPixmapIconEngineEntry(abs, size, mode, state);
        }
        return;
    }
    // Special case for reading Windows ".ico" files. Historically (QTBUG-39287),
    // these files may contain low-resolution images. As this information is lost,
    // ICOReader sets the original format as an image text key value. Read all matching
    // images into a list trying to find the highest quality per size.
    QList<QImage> icoImages;
    while (imageReader.read(&image)) {
        if (ignoreSize || image.size() == size) {
            const int position = findBySize(icoImages, image.size());
            if (position >= 0) { // Higher quality available? -> replace.
                if (origIcoDepth(image) > origIcoDepth(icoImages.at(position)))
                    icoImages[position] = image;
            } else {
                icoImages.append(image);
            }
        }
    }
    for (const QImage &i : std::as_const(icoImages))
        pixmaps += QPixmapIconEngineEntry(abs, i, mode, state);
    if (icoImages.isEmpty() && !ignoreSize) // Add placeholder with the filename and empty pixmap for the size.
        pixmaps += QPixmapIconEngineEntry(abs, size, mode, state);
}
 
bool QPixmapIconEngine::isNull()
{
    return pixmaps.isEmpty();
}
 
QString QPixmapIconEngine::key() const
{
    return "QPixmapIconEngine"_L1;
}
 
QIconEngine *QPixmapIconEngine::clone() const
{
    return new QPixmapIconEngine(*this);
}
 
bool QPixmapIconEngine::read(QDataStream &in)
{
    int num_entries;
    QPixmap pm;
    QString fileName;
    QSize sz;
    uint mode;
    uint state;
 
    in >> num_entries;
    for (int i=0; i < num_entries; ++i) {
        if (in.atEnd()) {
            pixmaps.clear();
            return false;
        }
        in >> pm;
        in >> fileName;
        in >> sz;
        in >> mode;
        in >> state;
        if (pm.isNull()) {
            addFile(fileName, sz, QIcon::Mode(mode), QIcon::State(state));
        } else {
            QPixmapIconEngineEntry pe(fileName, sz, QIcon::Mode(mode), QIcon::State(state));
            pe.pixmap = pm;
            pixmaps += pe;
        }
    }
    return true;
}
 
bool QPixmapIconEngine::write(QDataStream &out) const
{
    int num_entries = pixmaps.size();
    out << num_entries;
    for (int i=0; i < num_entries; ++i) {
        if (pixmaps.at(i).pixmap.isNull())
            out << QPixmap(pixmaps.at(i).fileName);
        else
            out << pixmaps.at(i).pixmap;
        out << pixmaps.at(i).fileName;
        out << pixmaps.at(i).size;
        out << (uint) pixmaps.at(i).mode;
        out << (uint) pixmaps.at(i).state;
    }
    return true;
}
 
Q_GLOBAL_STATIC_WITH_ARGS(QFactoryLoader, iceLoader,
    (QIconEngineFactoryInterface_iid, "/iconengines"_L1, Qt::CaseInsensitive))
 
QFactoryLoader *qt_iconEngineFactoryLoader()
{
    return iceLoader();
}
 
 
QIcon::QIcon() noexcept
    : d(nullptr)
{
}
 
QIcon::QIcon(const QPixmap &pixmap)
    :d(nullptr)
{
    addPixmap(pixmap);
}
 
QIcon::QIcon(const QIcon &other)
    :d(other.d)
{
    if (d)
        d->ref.ref();
}
 
QIcon::QIcon(const QString &fileName)
    : d(nullptr)
{
    addFile(fileName);
}
 
 
QIcon::QIcon(QIconEngine *engine)
    :d(new QIconPrivate(engine))
{
}
 
QIcon::~QIcon()
{
    if (d && !d->ref.deref())
        delete d;
}
 
QIcon &QIcon::operator=(const QIcon &other)
{
    if (other.d)
        other.d->ref.ref();
    if (d && !d->ref.deref())
        delete d;
    d = other.d;
    return *this;
}
 
QIcon::operator QVariant() const
{
    return QVariant::fromValue(*this);
}
 
qint64 QIcon::cacheKey() const
{
    if (!d)
        return 0;
    return (((qint64) d->serialNum) << 32) | ((qint64) (d->detach_no));
}
 
QPixmap QIcon::pixmap(const QSize &size, Mode mode, State state) const
{
    if (!d)
        return QPixmap();
    const qreal dpr = -1; // don't know target dpr
    return pixmap(size, dpr, mode, state);
}
 
QPixmap QIcon::pixmap(const QSize &size, qreal devicePixelRatio, Mode mode, State state) const
{
    if (!d)
        return QPixmap();
 
    // Use the global devicePixelRatio if the caller does not know the target dpr
    if (devicePixelRatio == -1)
        devicePixelRatio = qApp->devicePixelRatio();
 
    // Handle the simple normal-dpi case
    if (!(devicePixelRatio > 1.0)) {
        QPixmap pixmap = d->engine->pixmap(size, mode, state);
        pixmap.setDevicePixelRatio(1.0);
        return pixmap;
    }
 
    // Try get a pixmap that is big enough to be displayed at device pixel resolution.
    QPixmap pixmap = d->engine->scaledPixmap(size * devicePixelRatio, mode, state, devicePixelRatio);
    pixmap.setDevicePixelRatio(d->pixmapDevicePixelRatio(devicePixelRatio, size, pixmap.size()));
    return pixmap;
}
 
#if QT_DEPRECATED_SINCE(6, 0)
QPixmap QIcon::pixmap(QWindow *window, const QSize &size, Mode mode, State state) const
{
    if (!d)
        return QPixmap();
 
    qreal devicePixelRatio = window ? window->devicePixelRatio() : qApp->devicePixelRatio();
    return pixmap(size, devicePixelRatio, mode, state);
}
#endif
 
 
QSize QIcon::actualSize(const QSize &size, Mode mode, State state) const
{
    if (!d)
        return QSize();
 
    const qreal devicePixelRatio = qApp->devicePixelRatio();
 
    // Handle the simple normal-dpi case:
    if (!(devicePixelRatio > 1.0))
        return d->engine->actualSize(size, mode, state);
 
    const QSize actualSize = d->engine->actualSize(size * devicePixelRatio, mode, state);
    return actualSize / d->pixmapDevicePixelRatio(devicePixelRatio, size, actualSize);
}
 
#if QT_DEPRECATED_SINCE(6, 0)
QSize QIcon::actualSize(QWindow *window, const QSize &size, Mode mode, State state) const
{
    if (!d)
        return QSize();
 
    qreal devicePixelRatio = window ? window->devicePixelRatio() : qApp->devicePixelRatio();
 
    // Handle the simple normal-dpi case:
    if (!(devicePixelRatio > 1.0))
        return d->engine->actualSize(size, mode, state);
 
    QSize actualSize = d->engine->actualSize(size * devicePixelRatio, mode, state);
    return actualSize / d->pixmapDevicePixelRatio(devicePixelRatio, size, actualSize);
}
#endif
 
void QIcon::paint(QPainter *painter, const QRect &rect, Qt::Alignment alignment, Mode mode, State state) const
{
    if (!d || !painter)
        return;
 
    // Copy of QStyle::alignedRect
    const QSize size = d->engine->actualSize(rect.size(), mode, state);
    alignment = QGuiApplicationPrivate::visualAlignment(painter->layoutDirection(), alignment);
    int x = rect.x();
    int y = rect.y();
    int w = size.width();
    int h = size.height();
    if ((alignment & Qt::AlignVCenter) == Qt::AlignVCenter)
        y += rect.size().height()/2 - h/2;
    else if ((alignment & Qt::AlignBottom) == Qt::AlignBottom)
        y += rect.size().height() - h;
    if ((alignment & Qt::AlignRight) == Qt::AlignRight)
        x += rect.size().width() - w;
    else if ((alignment & Qt::AlignHCenter) == Qt::AlignHCenter)
        x += rect.size().width()/2 - w/2;
    QRect alignedRect(x, y, w, h);
 
    d->engine->paint(painter, alignedRect, mode, state);
}
 
bool QIcon::isNull() const
{
    return !d || d->engine->isNull();
}
 
bool QIcon::isDetached() const
{
    return !d || d->ref.loadRelaxed() == 1;
}
 
void QIcon::detach()
{
    if (d) {
        if (d->engine->isNull()) {
            if (!d->ref.deref())
                delete d;
            d = nullptr;
            return;
        } else if (d->ref.loadRelaxed() != 1) {
            QIconPrivate *x = new QIconPrivate(d->engine->clone());
            if (!d->ref.deref())
                delete d;
            d = x;
        }
        ++d->detach_no;
    }
}
 
void QIcon::addPixmap(const QPixmap &pixmap, Mode mode, State state)
{
    if (pixmap.isNull())
        return;
    detach();
    if (!d)
        d = new QIconPrivate(new QPixmapIconEngine);
    d->engine->addPixmap(pixmap, mode, state);
}
 
static QIconEngine *iconEngineFromSuffix(const QString &fileName, const QString &suffix)
{
    if (!suffix.isEmpty()) {
        const int index = iceLoader()->indexOf(suffix);
        if (index != -1) {
            if (QIconEnginePlugin *factory = qobject_cast<QIconEnginePlugin*>(iceLoader()->instance(index))) {
                return factory->create(fileName);
            }
        }
    }
    return nullptr;
}
 
void QIcon::addFile(const QString &fileName, const QSize &size, Mode mode, State state)
{
    if (fileName.isEmpty())
        return;
    detach();
    if (!d) {
 
        QFileInfo info(fileName);
        QString suffix = info.suffix();
#if QT_CONFIG(mimetype)
        if (suffix.isEmpty())
            suffix = QMimeDatabase().mimeTypeForFile(info).preferredSuffix(); // determination from contents
#endif // mimetype
        QIconEngine *engine = iconEngineFromSuffix(fileName, suffix);
        d = new QIconPrivate(engine ? engine : new QPixmapIconEngine);
    }
 
    d->engine->addFile(fileName, size, mode, state);
 
    // Check if a "@Nx" file exists and add it.
    QString atNxFileName = qt_findAtNxFile(fileName, qApp->devicePixelRatio());
    if (atNxFileName != fileName)
        d->engine->addFile(atNxFileName, size, mode, state);
}
 
QList<QSize> QIcon::availableSizes(Mode mode, State state) const
{
    if (!d || !d->engine)
        return QList<QSize>();
    return d->engine->availableSizes(mode, state);
}
 
QString QIcon::name() const
{
    if (!d || !d->engine)
        return QString();
    return d->engine->iconName();
}
 
void QIcon::setThemeSearchPaths(const QStringList &paths)
{
    QIconLoader::instance()->setThemeSearchPath(paths);
}
 
QStringList QIcon::themeSearchPaths()
{
    return QIconLoader::instance()->themeSearchPaths();
}
 
QStringList QIcon::fallbackSearchPaths()
{
    return QIconLoader::instance()->fallbackSearchPaths();
}
 
void QIcon::setFallbackSearchPaths(const QStringList &paths)
{
    QIconLoader::instance()->setFallbackSearchPaths(paths);
}
 
void QIcon::setThemeName(const QString &name)
{
    QIconLoader::instance()->setThemeName(name);
}
 
QString QIcon::themeName()
{
    return QIconLoader::instance()->themeName();
}
 
QString QIcon::fallbackThemeName()
{
    return QIconLoader::instance()->fallbackThemeName();
}
 
void QIcon::setFallbackThemeName(const QString &name)
{
    QIconLoader::instance()->setFallbackThemeName(name);
}
 
QIcon QIcon::fromTheme(const QString &name)
{
 
    if (QIcon *cachedIcon = qtIconCache()->object(name))
        return *cachedIcon;
 
    if (QDir::isAbsolutePath(name))
        return QIcon(name);
 
    QIcon icon(new QThemeIconEngine(name));
    qtIconCache()->insert(name, new QIcon(icon));
    return icon;
}
 
QIcon QIcon::fromTheme(const QString &name, const QIcon &fallback)
{
    QIcon icon = fromTheme(name);
 
    if (icon.isNull() || icon.availableSizes().isEmpty())
        return fallback;
 
    return icon;
}
 
bool QIcon::hasThemeIcon(const QString &name)
{
    QIcon icon = fromTheme(name);
 
    return icon.name() == name;
}
 
static constexpr auto themeIconMapping = qOffsetStringArray(
    "address-book-new",
    "application-exit",
    "appointment-new",
    "call-start",
    "call-stop",
    "contact-new",
    "document-new",
    "document-open",
    "document-open-recent",
    "document-page-setup",
    "document-print",
    "document-print-preview",
    "document-properties",
    "document-revert",
    "document-save",
    "document-save-as",
    "document-send",
    "edit-clear",
    "edit-copy",
    "edit-cut",
    "edit-delete",
    "edit-find",
    "edit-paste",
    "edit-redo",
    "edit-select-all",
    "edit-undo",
    "folder-new",
    "format-indent-less",
    "format-indent-more",
    "format-justify-center",
    "format-justify-fill",
    "format-justify-left",
    "format-justify-right",
    "format-text-direction-ltr",
    "format-text-direction-rtl",
    "format-text-bold",
    "format-text-italic",
    "format-text-underline",
    "format-text-strikethrough",
    "go-down",
    "go-home",
    "go-next",
    "go-previous",
    "go-up",
    "help-about",
    "help-faq",
    "insert-image",
    "insert-link",
    "insert-text",
    "list-add",
    "list-remove",
    "mail-forward",
    "mail-mark-important",
    "mail-mark-read",
    "mail-mark-unread",
    "mail-message-new",
    "mail-reply-all",
    "mail-reply-sender",
    "mail-send",
    "media-eject",
    "media-playback-pause",
    "media-playback-start",
    "media-playback-stop",
    "media-record",
    "media-seek-backward",
    "media-seek-forward",
    "media-skip-backward",
    "media-skip-forward",
    "object-rotate-left",
    "object-rotate-right",
    "process-stop",
    "system-lock-screen",
    "system-log-out",
    "system-search",
    "system-reboot",
    "system-shutdown",
    "tools-check-spelling",
    "view-fullscreen",
    "view-refresh",
    "view-restore",
    "window-close",
    "window-new",
    "zoom-fit-best",
    "zoom-in",
    "zoom-out",
 
    "audio-card",
    "audio-input-microphone",
    "battery",
    "camera-photo",
    "camera-video",
    "camera-web",
    "computer",
    "drive-harddisk",
    "drive-optical",
    "input-gaming",
    "input-keyboard",
    "input-mouse",
    "input-tablet",
    "media-flash",
    "media-optical",
    "media-tape",
    "multimedia-player",
    "network-wired",
    "network-wireless",
    "phone",
    "printer",
    "scanner",
    "video-display",
 
    "appointment-missed",
    "appointment-soon",
    "audio-volume-high",
    "audio-volume-low",
    "audio-volume-medium",
    "audio-volume-muted",
    "battery-caution",
    "battery-low",
    "dialog-error",
    "dialog-information",
    "dialog-password",
    "dialog-question",
    "dialog-warning",
    "folder-drag-accept",
    "folder-open",
    "folder-visiting",
    "image-loading",
    "image-missing",
    "mail-attachment",
    "mail-unread",
    "mail-read",
    "mail-replied",
    "media-playlist-repeat",
    "media-playlist-shuffle",
    "network-offline",
    "printer-printing",
    "security-high",
    "security-low",
    "software-update-available",
    "software-update-urgent",
    "sync-error",
    "sync-synchronizing",
    "user-available",
    "user-offline",
    "weather-clear",
    "weather-clear-night",
    "weather-few-clouds",
    "weather-few-clouds-night",
    "weather-fog",
    "weather-showers",
    "weather-snow",
    "weather-storm"
);
static_assert(QIcon::ThemeIcon::NThemeIcons == QIcon::ThemeIcon(themeIconMapping.count()));
 
static constexpr QLatin1StringView themeIconName(QIcon::ThemeIcon icon)
{
    using ThemeIconIndex = std::underlying_type_t<QIcon::ThemeIcon>;
    const auto index = static_cast<ThemeIconIndex>(icon);
    Q_ASSERT(index < themeIconMapping.count());
    return QLatin1StringView(themeIconMapping.viewAt(index));
}
 
bool QIcon::hasThemeIcon(QIcon::ThemeIcon icon)
{
    return hasThemeIcon(themeIconName(icon));
}
 
QIcon QIcon::fromTheme(QIcon::ThemeIcon icon)
{
    return fromTheme(themeIconName(icon));
}
 
QIcon QIcon::fromTheme(QIcon::ThemeIcon icon, const QIcon &fallback)
{
    return fromTheme(themeIconName(icon), fallback);
}
 
void QIcon::setIsMask(bool isMask)
{
    detach();
    if (!d)
        d = new QIconPrivate(new QPixmapIconEngine);
    d->is_mask = isMask;
}
 
bool QIcon::isMask() const
{
    if (!d)
        return false;
    return d->is_mask;
}
 
/*****************************************************************************
  QIcon stream functions
 *****************************************************************************/
#if !defined(QT_NO_DATASTREAM)
QDataStream &operator<<(QDataStream &s, const QIcon &icon)
{
    if (s.version() >= QDataStream::Qt_4_3) {
        if (icon.isNull()) {
            s << QString();
        } else {
            s << icon.d->engine->key();
            icon.d->engine->write(s);
        }
    } else if (s.version() == QDataStream::Qt_4_2) {
        if (icon.isNull()) {
            s << 0;
        } else {
            QPixmapIconEngine *engine = static_cast<QPixmapIconEngine *>(icon.d->engine);
            int num_entries = engine->pixmaps.size();
            s << num_entries;
            for (int i=0; i < num_entries; ++i) {
                s << engine->pixmaps.at(i).pixmap;
                s << engine->pixmaps.at(i).fileName;
                s << engine->pixmaps.at(i).size;
                s << (uint) engine->pixmaps.at(i).mode;
                s << (uint) engine->pixmaps.at(i).state;
            }
        }
    } else {
        s << QPixmap(icon.pixmap(22,22));
    }
    return s;
}
 
QDataStream &operator>>(QDataStream &s, QIcon &icon)
{
    if (s.version() >= QDataStream::Qt_4_3) {
        icon = QIcon();
        QString key;
        s >> key;
        if (key == "QPixmapIconEngine"_L1) {
            icon.d = new QIconPrivate(new QPixmapIconEngine);
            icon.d->engine->read(s);
        } else if (key == "QIconLoaderEngine"_L1 || key == "QThemeIconEngine"_L1) {
            icon.d = new QIconPrivate(new QThemeIconEngine);
            icon.d->engine->read(s);
        } else {
            const int index = iceLoader()->indexOf(key);
            if (index != -1) {
                if (QIconEnginePlugin *factory = qobject_cast<QIconEnginePlugin*>(iceLoader()->instance(index))) {
                    if (QIconEngine *engine= factory->create()) {
                        icon.d = new QIconPrivate(engine);
                        engine->read(s);
                    } // factory
                } // instance
            } // index
        }
    } else if (s.version() == QDataStream::Qt_4_2) {
        icon = QIcon();
        int num_entries;
        QPixmap pm;
        QString fileName;
        QSize sz;
        uint mode;
        uint state;
 
        s >> num_entries;
        for (int i=0; i < num_entries; ++i) {
            s >> pm;
            s >> fileName;
            s >> sz;
            s >> mode;
            s >> state;
            if (pm.isNull())
                icon.addFile(fileName, sz, QIcon::Mode(mode), QIcon::State(state));
            else
                icon.addPixmap(pm, QIcon::Mode(mode), QIcon::State(state));
        }
    } else {
        QPixmap pm;
        s >> pm;
        icon.addPixmap(pm);
    }
    return s;
}
 
#endif //QT_NO_DATASTREAM
 
#ifndef QT_NO_DEBUG_STREAM
QDebug operator<<(QDebug dbg, const QIcon &i)
{
    QDebugStateSaver saver(dbg);
    dbg.resetFormat();
    dbg.nospace();
    dbg << "QIcon(";
    if (i.isNull()) {
        dbg << "null";
    } else {
        if (!i.name().isEmpty())
            dbg << i.name() << ',';
        dbg << "availableSizes[normal,Off]=" << i.availableSizes()
            << ",cacheKey=" << Qt::showbase << Qt::hex << i.cacheKey() << Qt::dec << Qt::noshowbase;
    }
    dbg << ')';
    return dbg;
}
#endif
 
QString qt_findAtNxFile(const QString &baseFileName, qreal targetDevicePixelRatio,
                        qreal *sourceDevicePixelRatio)
{
    if (targetDevicePixelRatio <= 1.0)
        return baseFileName;
 
    static bool disableNxImageLoading = !qEnvironmentVariableIsEmpty("QT_HIGHDPI_DISABLE_2X_IMAGE_LOADING");
    if (disableNxImageLoading)
        return baseFileName;
 
    int dotIndex = baseFileName.lastIndexOf(u'.');
    if (dotIndex == -1) { /* no dot */
        dotIndex = baseFileName.size(); /* append */
    } else if (dotIndex >= 2 && baseFileName[dotIndex - 1] == u'9'
        && baseFileName[dotIndex - 2] == u'.') {
        // If the file has a .9.* (9-patch image) extension, we must ensure that the @nx goes before it.
        dotIndex -= 2;
    }
 
    QString atNxfileName = baseFileName;
    atNxfileName.insert(dotIndex, "@2x"_L1);
    // Check for @Nx, ..., @3x, @2x file versions,
    for (int n = qMin(qCeil(targetDevicePixelRatio), 9); n > 1; --n) {
        atNxfileName[dotIndex + 1] = QLatin1Char('0' + n);
        if (QFile::exists(atNxfileName)) {
            if (sourceDevicePixelRatio)
                *sourceDevicePixelRatio = n;
            return atNxfileName;
        }
    }
 
    return baseFileName;
}
 
QT_END_NAMESPACE
#endif //QT_NO_ICON