From a87dbf0d08d58b829ca2fa036d589ad4fd48949f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Samuel=20R=C3=B8dal?= <samuel.rodal@nokia.com>
Date: Tue, 26 Oct 2010 15:46:11 +0200
Subject: Fixed race condition in raster paint engine.

We need to protect the gradient cache accesses with a mutex.

Task-number: QTBUG-14614
Reviewed-by: Bradley T. Hughes
---
 src/gui/painting/qpaintengine_raster.cpp |  2 ++
 tests/auto/qpainter/tst_qpainter.cpp     | 32 ++++++++++++++++++++++++++++++++
 2 files changed, 34 insertions(+)

diff --git a/src/gui/painting/qpaintengine_raster.cpp b/src/gui/painting/qpaintengine_raster.cpp
index 975ebb0..c03f82b 100644
--- a/src/gui/painting/qpaintengine_raster.cpp
+++ b/src/gui/painting/qpaintengine_raster.cpp
@@ -4811,6 +4811,7 @@ public:
         for (int i = 0; i < stops.size() && i <= 2; i++)
             hash_val += stops[i].second.rgba();
 
+        QMutexLocker lock(&mutex);
         QGradientColorTableHash::const_iterator it = cache.constFind(hash_val);
 
         if (it == cache.constEnd())
@@ -4844,6 +4845,7 @@ protected:
     }
 
     QGradientColorTableHash cache;
+    QMutex mutex;
 };
 
 void QGradientCache::generateGradientColorTable(const QGradient& gradient, uint *colorTable, int size, int opacity) const
diff --git a/tests/auto/qpainter/tst_qpainter.cpp b/tests/auto/qpainter/tst_qpainter.cpp
index beb83a1..4146c5e 100644
--- a/tests/auto/qpainter/tst_qpainter.cpp
+++ b/tests/auto/qpainter/tst_qpainter.cpp
@@ -251,6 +251,8 @@ private slots:
 
     void QTBUG5939_attachPainterPrivate();
 
+    void QTBUG14614_gradientCacheRaceCondition();
+
 private:
     void fillData();
     void setPenColor(QPainter& p);
@@ -4458,6 +4460,36 @@ void tst_QPainter::QTBUG5939_attachPainterPrivate()
     QCOMPARE(widget->deviceTransform, proxy->deviceTransform);
 }
 
+class GradientProducer : public QThread
+{
+protected:
+    void run();
+};
+
+void GradientProducer::run()
+{
+    QImage image(1, 1, QImage::Format_RGB32);
+    QPainter p(&image);
+
+    for (int i = 0; i < 1000; ++i) {
+        QLinearGradient g;
+        g.setColorAt(0, QColor(i % 256, 0, 0));
+        g.setColorAt(1, Qt::white);
+
+        p.fillRect(image.rect(), g);
+    }
+}
+
+void tst_QPainter::QTBUG14614_gradientCacheRaceCondition()
+{
+    const int threadCount = 16;
+    GradientProducer producers[threadCount];
+    for (int i = 0; i < threadCount; ++i)
+        producers[i].start();
+    for (int i = 0; i < threadCount; ++i)
+        producers[i].wait();
+}
+
 QTEST_MAIN(tst_QPainter)
 
 #include "tst_qpainter.moc"
-- 
cgit v0.12


From 4d0571667463997f5f1145408a2ba73ba293637a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Samuel=20R=C3=B8dal?= <samuel.rodal@nokia.com>
Date: Wed, 27 Oct 2010 12:57:42 +0200
Subject: Fix Windows compilation.

Don't take for granted that these are included...

Task-number: QTBUG-14614
Reviewed-by: Bradley T. Hughes
---
 src/gui/painting/qpaintengine_raster.cpp | 1 +
 tests/auto/qpainter/tst_qpainter.cpp     | 1 +
 2 files changed, 2 insertions(+)

diff --git a/src/gui/painting/qpaintengine_raster.cpp b/src/gui/painting/qpaintengine_raster.cpp
index c03f82b..d1c4cab 100644
--- a/src/gui/painting/qpaintengine_raster.cpp
+++ b/src/gui/painting/qpaintengine_raster.cpp
@@ -40,6 +40,7 @@
 ****************************************************************************/
 
 #include <QtCore/qglobal.h>
+#include <QtCore/qmutex.h>
 
 #define QT_FT_BEGIN_HEADER
 #define QT_FT_END_HEADER
diff --git a/tests/auto/qpainter/tst_qpainter.cpp b/tests/auto/qpainter/tst_qpainter.cpp
index 4146c5e..0a4de99 100644
--- a/tests/auto/qpainter/tst_qpainter.cpp
+++ b/tests/auto/qpainter/tst_qpainter.cpp
@@ -49,6 +49,7 @@
 #include <qfontmetrics.h>
 #include <qbitmap.h>
 #include <qimage.h>
+#include <qthread.h>
 #include <limits.h>
 #if !defined(Q_OS_WINCE) && !defined(Q_OS_SYMBIAN)
 #include <qprinter.h>
-- 
cgit v0.12