Lazily construct QPixmapData's for null pixmaps

Reviewed-by: Trond

8 files changed, 75 insertions, 38 deletions

diff --git a/src/gui/image/qpixmap.cpp b/src/gui/image/qpixmap.cpp
index 45ff5f4..c452b9a 100644
--- a/src/gui/image/qpixmap.cpp
+++ b/src/gui/image/qpixmap.cpp
@@ -113,13 +113,10 @@ void QPixmap::init(int w, int h, Type type)
 
 void QPixmap::init(int w, int h, int type)
 {
-    QGraphicsSystem* gs = QApplicationPrivate::graphicsSystem();
-    if (gs)
-        data = gs->createPixmapData(static_cast<QPixmapData::PixelType>(type));
+    if ((w > 0 && h > 0) || type == QPixmapData::BitmapType)
+        data = QPixmapData::create(w, h, (QPixmapData::PixelType) type);
     else
-        data = QGraphicsSystem::createDefaultPixmapData(static_cast<QPixmapData::PixelType>(type));
-
-    data->resize(w, h);
+        data = 0;
 }
 
 /*!
@@ -307,7 +304,7 @@ QPixmap::QPixmap(const char * const xpm[])
 
     QImage image(xpm);
     if (!image.isNull()) {
-        if (data->pixelType() == QPixmapData::BitmapType)
+        if (data && data->pixelType() == QPixmapData::BitmapType)
             *this = QBitmap::fromImage(image);
         else
             *this = fromImage(image);
@@ -322,8 +319,8 @@ QPixmap::QPixmap(const char * const xpm[])
 
 QPixmap::~QPixmap()
 {
-    Q_ASSERT(data->ref >= 1); // Catch if ref-counting changes again
-    if (data->is_cached && data->ref == 1) // ref will be decrememnted after destructor returns
+    Q_ASSERT(!data || data->ref >= 1); // Catch if ref-counting changes again
+    if (data && data->is_cached && data->ref == 1) // ref will be decrememnted after destructor returns
         QImagePixmapCleanupHooks::executePixmapDestructionHooks(this);
 }
 
@@ -544,7 +541,7 @@ bool QPixmap::isQBitmap() const
 */
 bool QPixmap::isNull() const
 {
-    return data->isNull();
+    return !data || data->isNull();
 }
 
 /*!
@@ -556,7 +553,7 @@ bool QPixmap::isNull() const
 */
 int QPixmap::width() const
 {
-    return data->width();
+    return data ? data->width() : 0;
 }
 
 /*!
@@ -568,7 +565,7 @@ int QPixmap::width() const
 */
 int QPixmap::height() const
 {
-    return data->height();
+    return data ? data->height() : 0;
 }
 
 /*!
@@ -581,7 +578,7 @@ int QPixmap::height() const
 */
 QSize QPixmap::size() const
 {
-    return QSize(data->width(), data->height());
+    return data ? QSize(data->width(), data->height()) : QSize();
 }
 
 /*!
@@ -593,7 +590,7 @@ QSize QPixmap::size() const
 */
 QRect QPixmap::rect() const
 {
-    return QRect(0, 0, data->width(), data->height());
+    return data ? QRect(0, 0, data->width(), data->height()) : QRect();
 }
 
 /*!
@@ -609,7 +606,7 @@ QRect QPixmap::rect() const
 */
 int QPixmap::depth() const
 {
-    return data->depth();
+    return data ? data->depth() : 0;
 }
 
 /*!
@@ -639,7 +636,7 @@ void QPixmap::resize_helper(const QSize &s)
         return;
 
     // Create new pixmap
-    QPixmap pm(QSize(w, h), data->type);
+    QPixmap pm(QSize(w, h), data ? data->type : QPixmapData::PixmapType);
     bool uninit = false;
 #if defined(Q_WS_X11)
     QX11PixmapData *x11Data = data->classId() == QPixmapData::X11Class ? static_cast<QX11PixmapData*>(data.data()) : 0;
@@ -728,6 +725,9 @@ void QPixmap::setMask(const QBitmap &mask)
         return;
     }
 
+    if (isNull())
+        return;
+
     if (static_cast<const QPixmap &>(mask).data == data) // trying to selfmask
        return;
 
@@ -826,11 +826,14 @@ bool QPixmap::load(const QString &fileName, const char *format, Qt::ImageConvers
 
     QFileInfo info(fileName);
     QString key = QLatin1String("qt_pixmap_") + info.absoluteFilePath() + QLatin1Char('_') + QString::number(info.lastModified().toTime_t()) + QLatin1Char('_') +
-                  QString::number(info.size()) + QLatin1Char('_') + QString::number(data->pixelType());
+        QString::number(info.size()) + QLatin1Char('_') + QString::number(data ? data->pixelType() : QPixmapData::PixmapType);
 
     if (QPixmapCache::find(key, *this))
         return true;
 
+    if (!data)
+        data = QPixmapData::create(0, 0, QPixmapData::PixmapType);
+
     if (data->fromFile(fileName, format, flags)) {
         QPixmapCache::insert(key, *this);
         return true;
@@ -863,6 +866,9 @@ bool QPixmap::loadFromData(const uchar *buf, uint len, const char *format, Qt::I
     if (len == 0 || buf == 0)
         return false;
 
+    if (!data)
+        data = QPixmapData::create(0, 0, QPixmapData::PixmapType);
+
     return data->fromData(buf, len, format, flags);
 }
 
@@ -1008,6 +1014,9 @@ int QPixmap::serialNumber() const
 */
 qint64 QPixmap::cacheKey() const
 {
+    if (isNull())
+        return 0;
+
     int classKey = data->classId();
     if (classKey >= 1024)
         classKey = -(classKey >> 10);
@@ -1224,7 +1233,7 @@ QPixmap::QPixmap(const QImage& image)
 
 QPixmap &QPixmap::operator=(const QImage &image)
 {
-    if (data->pixelType() == QPixmapData::BitmapType)
+    if (data && data->pixelType() == QPixmapData::BitmapType)
         *this = QBitmap::fromImage(image);
     else
         *this = fromImage(image);
@@ -1254,7 +1263,7 @@ bool QPixmap::loadFromData(const uchar *buf, uint len, const char *format, Color
 */
 bool QPixmap::convertFromImage(const QImage &image, ColorMode mode)
 {
-    if (data->pixelType() == QPixmapData::BitmapType)
+    if (data && data->pixelType() == QPixmapData::BitmapType)
         *this = QBitmap::fromImage(image, colorModeToFlags(mode));
     else
         *this = fromImage(image, colorModeToFlags(mode));
@@ -1341,7 +1350,7 @@ Q_GUI_EXPORT void copyBlt(QPixmap *dst, int dx, int dy,
 
 bool QPixmap::isDetached() const
 {
-    return data->ref == 1;
+    return data && data->ref == 1;
 }
 
 /*! \internal
@@ -1753,7 +1762,7 @@ QPixmap QPixmap::transformed(const QMatrix &matrix, Qt::TransformationMode mode)
 */
 bool QPixmap::hasAlpha() const
 {
-    return (data->hasAlphaChannel() || !data->mask().isNull());
+    return data && (data->hasAlphaChannel() || !data->mask().isNull());
 }
 
 /*!
@@ -1764,7 +1773,7 @@ bool QPixmap::hasAlpha() const
 */
 bool QPixmap::hasAlphaChannel() const
 {
-    return data->hasAlphaChannel();
+    return data && data->hasAlphaChannel();
 }
 
 /*!
@@ -1772,7 +1781,7 @@ bool QPixmap::hasAlphaChannel() const
 */
 int QPixmap::metric(PaintDeviceMetric metric) const
 {
-    return data->metric(metric);
+    return data ? data->metric(metric) : 0;
 }
 
 /*!
@@ -1844,7 +1853,7 @@ void QPixmap::setAlphaChannel(const QPixmap &alphaChannel)
 */
 QPixmap QPixmap::alphaChannel() const
 {
-    return data->alphaChannel();
+    return data ? data->alphaChannel() : QPixmap();
 }
 
 /*!
@@ -1852,7 +1861,7 @@ QPixmap QPixmap::alphaChannel() const
 */
 QPaintEngine *QPixmap::paintEngine() const
 {
-    return data->paintEngine();
+    return data ? data->paintEngine() : 0;
 }
 
 /*!
@@ -1867,7 +1876,7 @@ QPaintEngine *QPixmap::paintEngine() const
 */
 QBitmap QPixmap::mask() const
 {
-    return data->mask();
+    return data ? data->mask() : QBitmap();
 }
 
 /*!
@@ -1916,6 +1925,9 @@ int QPixmap::defaultDepth()
 */
 void QPixmap::detach()
 {
+    if (!data)
+        return;
+
     QPixmapData::ClassId id = data->classId();
     if (id == QPixmapData::RasterClass) {
         QRasterPixmapData *rasterData = static_cast<QRasterPixmapData*>(data.data());
diff --git a/src/gui/image/qpixmap_mac.cpp b/src/gui/image/qpixmap_mac.cpp
index afa6f83..15350e8 100644
--- a/src/gui/image/qpixmap_mac.cpp
+++ b/src/gui/image/qpixmap_mac.cpp
@@ -965,6 +965,9 @@ Qt::HANDLE QPixmap::macQDAlphaHandle() const
 
 Qt::HANDLE QPixmap::macCGHandle() const
 {
+    if (isNull())
+        return 0;
+
     if (data->classId() == QPixmapData::MacClass) {
         QMacPixmapData *d = static_cast<QMacPixmapData *>(data.data());
         if (!d->cg_data)
diff --git a/src/gui/image/qpixmap_qws.cpp b/src/gui/image/qpixmap_qws.cpp
index 6b4283e..a8516a5 100644
--- a/src/gui/image/qpixmap_qws.cpp
+++ b/src/gui/image/qpixmap_qws.cpp
@@ -114,7 +114,7 @@ QPixmap QPixmap::grabWindow(WId window, int x, int y, int w, int h)
 
 QRgb* QPixmap::clut() const
 {
-    if (data->classId() == QPixmapData::RasterClass) {
+    if (data && data->classId() == QPixmapData::RasterClass) {
         const QRasterPixmapData *d = static_cast<const QRasterPixmapData*>(data.data());
         return d->image.colorTable().data();
     }
@@ -124,7 +124,7 @@ QRgb* QPixmap::clut() const
 
 int QPixmap::numCols() const
 {
-    if (data->classId() == QPixmapData::RasterClass) {
+    if (data && data->classId() == QPixmapData::RasterClass) {
         const QRasterPixmapData *d = static_cast<const QRasterPixmapData*>(data.data());
         return d->image.numColors();
     }
@@ -134,7 +134,7 @@ int QPixmap::numCols() const
 
 const uchar* QPixmap::qwsBits() const
 {
-    if (data->classId() == QPixmapData::RasterClass) {
+    if (data && data->classId() == QPixmapData::RasterClass) {
         const QRasterPixmapData *d = static_cast<const QRasterPixmapData*>(data.data());
         return d->image.bits();
     }
@@ -144,7 +144,7 @@ const uchar* QPixmap::qwsBits() const
 
 int QPixmap::qwsBytesPerLine() const
 {
-    if (data->classId() == QPixmapData::RasterClass) {
+    if (data && data->classId() == QPixmapData::RasterClass) {
         const QRasterPixmapData *d = static_cast<const QRasterPixmapData*>(data.data());
         return d->image.bytesPerLine();
     }
diff --git a/src/gui/image/qpixmap_s60.cpp b/src/gui/image/qpixmap_s60.cpp
index 666d608..d4c97e1 100644
--- a/src/gui/image/qpixmap_s60.cpp
+++ b/src/gui/image/qpixmap_s60.cpp
@@ -311,7 +311,7 @@ QPixmap QPixmap::grabWindow(WId winId, int x, int y, int w, int h)
 CFbsBitmap *QPixmap::toSymbianCFbsBitmap() const
 {
     QPixmapData *data = pixmapData();
-    if (data->isNull())
+    if (!data || data->isNull())
         return 0;
 
     return reinterpret_cast<CFbsBitmap*>(data->toNativeType(QPixmapData::FbsBitmap));
@@ -337,8 +337,9 @@ QPixmap QPixmap::fromSymbianCFbsBitmap(CFbsBitmap *bitmap)
     if (!bitmap)
         return QPixmap();
 
-    QPixmap pixmap;
-    pixmap.pixmapData()->fromNativeType(reinterpret_cast<void*>(bitmap), QPixmapData::FbsBitmap);
+    QScopedPointer<QS60PixmapData> data(new QS60PixmapData(QPixmapData::PixmapType));
+    data->fromNativeType(reinterpret_cast<void*>(bitmap), QPixmapData::FbsBitmap);
+    QPixmap pixmap(data.take());
     return pixmap;
 }
 
@@ -752,9 +753,9 @@ QPixmap QPixmap::fromSymbianRSgImage(RSgImage *sgImage)
     if (!sgImage)
         return QPixmap();
 
-    QPixmap pixmap;
-    pixmap.pixmapData()->fromNativeType(reinterpret_cast<void*>(sgImage), QPixmapData::SgImage);
-
+    QScopedPointer<QS60PixmapData> data(new QS60PixmapData(QPixmapData::PixmapType));
+    data->fromNativeType(reinterpret_cast<void*>(bitmap), QPixmapData::SgImage);
+    QPixmap pixmap(data.take());
     return pixmap;
 }
 
diff --git a/src/gui/image/qpixmap_win.cpp b/src/gui/image/qpixmap_win.cpp
index 1b61484..04027c1 100644
--- a/src/gui/image/qpixmap_win.cpp
+++ b/src/gui/image/qpixmap_win.cpp
@@ -121,6 +121,9 @@ QPixmap QPixmap::grabWindow(WId winId, int x, int y, int w, int h )
 
 HBITMAP QPixmap::toWinHBITMAP(HBitmapFormat format) const
 {
+    if (isNull())
+        return 0;
+
     HBITMAP bitmap = 0;
     if (data->classId() == QPixmapData::RasterClass) {
         QRasterPixmapData* d = static_cast<QRasterPixmapData*>(data.data());
diff --git a/src/gui/image/qpixmap_x11.cpp b/src/gui/image/qpixmap_x11.cpp
index ea9eff9..8a0120a 100644
--- a/src/gui/image/qpixmap_x11.cpp
+++ b/src/gui/image/qpixmap_x11.cpp
@@ -1976,6 +1976,9 @@ void QPixmap::x11SetScreen(int screen)
         return;
     }
 
+    if (isNull())
+        return;
+
     if (data->classId() != QPixmapData::X11Class)
         return;
 
@@ -2078,7 +2081,7 @@ bool QX11PixmapData::hasAlphaChannel() const
 
 const QX11Info &QPixmap::x11Info() const
 {
-    if (data->classId() == QPixmapData::X11Class)
+    if (data && data->classId() == QPixmapData::X11Class)
         return static_cast<QX11PixmapData*>(data.data())->xinfo;
     else {
         static QX11Info nullX11Info;
@@ -2135,7 +2138,7 @@ QPaintEngine* QX11PixmapData::paintEngine() const
 Qt::HANDLE QPixmap::x11PictureHandle() const
 {
 #ifndef QT_NO_XRENDER
-    if (data->classId() == QPixmapData::X11Class)
+    if (data && data->classId() == QPixmapData::X11Class)
         return static_cast<const QX11PixmapData*>(data.data())->picture;
     else
         return 0;
diff --git a/src/gui/image/qpixmapdata.cpp b/src/gui/image/qpixmapdata.cpp
index 1ad1f02..10194e4 100644
--- a/src/gui/image/qpixmapdata.cpp
+++ b/src/gui/image/qpixmapdata.cpp
@@ -51,6 +51,19 @@ QT_BEGIN_NAMESPACE
 const uchar qt_pixmap_bit_mask[] = { 0x01, 0x02, 0x04, 0x08,
                                      0x10, 0x20, 0x40, 0x80 };
 
+QPixmapData *QPixmapData::create(int w, int h, PixelType type)
+{
+    QPixmapData *data;
+    QGraphicsSystem* gs = QApplicationPrivate::graphicsSystem();
+    if (gs)
+        data = gs->createPixmapData(static_cast<QPixmapData::PixelType>(type));
+    else
+        data = QGraphicsSystem::createDefaultPixmapData(static_cast<QPixmapData::PixelType>(type));
+    data->resize(w, h);
+    return data;
+}
+
+
 QPixmapData::QPixmapData(PixelType pixelType, int objectId)
     : w(0),
       h(0),
diff --git a/src/gui/image/qpixmapdata_p.h b/src/gui/image/qpixmapdata_p.h
index e99409c..d1bb92a 100644
--- a/src/gui/image/qpixmapdata_p.h
+++ b/src/gui/image/qpixmapdata_p.h
@@ -122,6 +122,8 @@ public:
     virtual void fromNativeType(void* pixmap, NativeType type);
 #endif
 
+    static QPixmapData *create(int w, int h, PixelType type);
+
 protected:
     void setSerialNumber(int serNo);
     int w;