QtGui: Use QImage::constBits()/constScanLine() in non-const contexts.

Prevent potential detaching by using constBits()/constScanLine() instead
of bits()/scanLine().

Change-Id: If03f8d4d3b8ed4c07aed5eff7f580e57ca771919
Reviewed-by: Gunnar Sletta <gunnar@sletta.org>
Reviewed-by: Marc Mutz <marc.mutz@kdab.com>

3 files changed, 7 insertions, 7 deletions

diff --git a/src/gui/painting/qpaintengine_raster.cpp b/src/gui/painting/qpaintengine_raster.cpp
index fb44a7aeb1..9d981dcc2c 100644
--- a/src/gui/painting/qpaintengine_raster.cpp
+++ b/src/gui/painting/qpaintengine_raster.cpp
@@ -3610,7 +3610,7 @@ QImage QRasterBuffer::colorizeBitmap(const QImage &image, const QColor &color)
 {
     Q_ASSERT(image.depth() == 1);
 
-    QImage sourceImage = image.convertToFormat(QImage::Format_MonoLSB);
+    const QImage sourceImage = image.convertToFormat(QImage::Format_MonoLSB);
     QImage dest = QImage(sourceImage.size(), QImage::Format_ARGB32_Premultiplied);
 
     QRgb fg = qPremultiply(color.rgba());
@@ -3619,7 +3619,7 @@ QImage QRasterBuffer::colorizeBitmap(const QImage &image, const QColor &color)
     int height = sourceImage.height();
     int width = sourceImage.width();
     for (int y=0; y<height; ++y) {
-        uchar *source = sourceImage.scanLine(y);
+        const uchar *source = sourceImage.constScanLine(y);
         QRgb *target = reinterpret_cast<QRgb *>(dest.scanLine(y));
         if (!source || !target)
             QT_THROW(std::bad_alloc()); // we must have run out of memory
diff --git a/src/gui/painting/qregion.cpp b/src/gui/painting/qregion.cpp
index 5e648eabf5..757c78cec8 100644
--- a/src/gui/painting/qregion.cpp
+++ b/src/gui/painting/qregion.cpp
@@ -3735,7 +3735,7 @@ static QRegionPrivate *PolygonRegion(const QPoint *Pts, int Count, int rule)
 
 QRegionPrivate *qt_bitmapToRegion(const QBitmap& bitmap)
 {
-    QImage image = bitmap.toImage();
+    const QImage image = bitmap.toImage();
 
     QRegionPrivate *region = new QRegionPrivate;
 
@@ -3753,7 +3753,7 @@ QRegionPrivate *qt_bitmapToRegion(const QBitmap& bitmap)
     int x,
         y;
     for (y = 0; y < image.height(); ++y) {
-        uchar *line = image.scanLine(y);
+        const uchar *line = image.constScanLine(y);
         int w = image.width();
         uchar all = zero;
         int prev1 = -1;
diff --git a/src/gui/painting/qtextureglyphcache.cpp b/src/gui/painting/qtextureglyphcache.cpp
index 97f82d16d3..20039d902a 100644
--- a/src/gui/painting/qtextureglyphcache.cpp
+++ b/src/gui/painting/qtextureglyphcache.cpp
@@ -339,7 +339,7 @@ void QImageTextureGlyphCache::fillTexture(const Coord &c, glyph_t g, QFixed subP
             uchar *dest = d + (c.y + y) *dbpl + c.x/8;
 
             if (y < mh) {
-                uchar *src = mask.scanLine(y);
+                const uchar *src = mask.constScanLine(y);
                 for (int x = 0; x < c.w/8; ++x) {
                     if (x < (mw+7)/8)
                         dest[x] = src[x];
@@ -361,7 +361,7 @@ void QImageTextureGlyphCache::fillTexture(const Coord &c, glyph_t g, QFixed subP
             for (int y = 0; y < c.h; ++y) {
                 uchar *dest = d + (c.y + y) *dbpl + c.x;
                 if (y < mh) {
-                    uchar *src = (uchar *) mask.scanLine(y);
+                    const uchar *src = mask.constScanLine(y);
                     for (int x = 0; x < c.w; ++x) {
                         if (x < mw)
                             dest[x] = (src[x >> 3] & (1 << (7 - (x & 7)))) > 0 ? 255 : 0;
@@ -372,7 +372,7 @@ void QImageTextureGlyphCache::fillTexture(const Coord &c, glyph_t g, QFixed subP
             for (int y = 0; y < c.h; ++y) {
                 uchar *dest = d + (c.y + y) *dbpl + c.x;
                 if (y < mh) {
-                    uchar *src = (uchar *) mask.scanLine(y);
+                    const uchar *src = mask.constScanLine(y);
                     for (int x = 0; x < c.w; ++x) {
                         if (x < mw)
                             dest[x] = src[x];