QQuickSpriteEngine: avoid entering infinite loop in assembledImage()

Do not allow a frame size larger than the image size, otherwise
we would never leave "while (framesLeft > 0) {...}" as framesLeft is
never decremented because "copied/frameWidth" in the expression
"framesLeft -= copied/frameWidth;" always resolves to zero because
copied < frameWidth.

Task-number: QTBUG-53937
Change-Id: Ia777ec65d72562426b13533918efcaca5bcabdd7
Reviewed-by: Albert Astals Cid <albert.astals@canonical.com>
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>
Reviewed-by: Andy Nichols <andy.nichols@qt.io>

1 files changed, 39 insertions, 0 deletions

diff --git a/tests/auto/quick/qquickanimatedsprite/tst_qquickanimatedsprite.cpp b/tests/auto/quick/qquickanimatedsprite/tst_qquickanimatedsprite.cpp
index 3cb7ff511f..b34ac63b83 100644
--- a/tests/auto/quick/qquickanimatedsprite/tst_qquickanimatedsprite.cpp
+++ b/tests/auto/quick/qquickanimatedsprite/tst_qquickanimatedsprite.cpp
@@ -40,6 +40,7 @@
 #include <QtGui/qopenglcontext.h>
 #include <QtGui/qopenglfunctions.h>
 #include <QtGui/qoffscreensurface.h>
+#include <QtQml/qqmlproperty.h>
 
 class tst_qquickanimatedsprite : public QQmlDataTest
 {
@@ -55,6 +56,7 @@ private slots:
     void test_largeAnimation_data();
     void test_largeAnimation();
     void test_reparenting();
+    void test_changeSourceToSmallerImgKeepingBigFrameSize();
 };
 
 void tst_qquickanimatedsprite::initTestCase()
@@ -291,6 +293,43 @@ void tst_qquickanimatedsprite::test_reparenting()
     QTRY_COMPARE(QQuickItemPrivate::get(sprite)->polishScheduled, false);
 }
 
+class KillerThread : public QThread
+{
+    Q_OBJECT
+protected:
+    void run() Q_DECL_OVERRIDE {
+        sleep(3);
+        qFatal("Either the GUI or the render thread is stuck in an infinite loop.");
+    }
+};
+
+// Regression test for QTBUG-53937
+void tst_qquickanimatedsprite::test_changeSourceToSmallerImgKeepingBigFrameSize()
+{
+    QQuickView window;
+    window.setSource(testFileUrl("sourceSwitch.qml"));
+    window.show();
+    QVERIFY(QTest::qWaitForWindowExposed(&window));
+
+    QVERIFY(window.rootObject());
+    QQuickAnimatedSprite* sprite = qobject_cast<QQuickAnimatedSprite*>(window.rootObject());
+    QVERIFY(sprite);
+
+    QQmlProperty big(sprite, "big");
+    big.write(QVariant::fromValue(false));
+
+    KillerThread *killer = new KillerThread;
+    killer->start(); // will kill us in case the GUI or render thread enters an infinite loop
+
+    QTest::qWait(50); // let it draw with the new source.
+
+    // If we reach this point it's because we didn't hit QTBUG-53937
+
+    killer->terminate();
+    killer->wait();
+    delete killer;
+}
+
 QTEST_MAIN(tst_qquickanimatedsprite)
 
 #include "tst_qquickanimatedsprite.moc"