Merge remote-tracking branch 'qt/dev' into dev-highdpi

Conflicts:
	src/gui/kernel/qsimpledrag.cpp
	src/gui/kernel/qwindowsysteminterface.cpp
	src/gui/kernel/qwindowsysteminterface_p.h
	src/plugins/platforms/xcb/qxcbwindow.cpp

Change-Id: Icd887552ade61d6a2b2527383970f7145aa00faf

1 files changed, 23 insertions, 0 deletions

diff --git a/tests/auto/corelib/tools/qringbuffer/tst_qringbuffer.cpp b/tests/auto/corelib/tools/qringbuffer/tst_qringbuffer.cpp
index 044fdbdee5..f9bca77ed3 100644
--- a/tests/auto/corelib/tools/qringbuffer/tst_qringbuffer.cpp
+++ b/tests/auto/corelib/tools/qringbuffer/tst_qringbuffer.cpp
@@ -48,6 +48,7 @@ private slots:
     void sizeWhenReserved();
     void free();
     void reserveAndRead();
+    void reserveFrontAndRead();
     void chop();
     void ungetChar();
     void indexOf();
@@ -219,6 +220,28 @@ void tst_QRingBuffer::reserveAndRead()
     QVERIFY(ringBuffer.size() == 0);
 }
 
+void tst_QRingBuffer::reserveFrontAndRead()
+{
+    QRingBuffer ringBuffer;
+    // fill buffer with an arithmetic progression
+    for (int i = 1; i < 256; ++i) {
+        QByteArray ba(i, char(i));
+        char *ringPos = ringBuffer.reserveFront(i);
+        QVERIFY(ringPos);
+        memcpy(ringPos, ba.constData(), i);
+    }
+
+    // readback and check stored data
+    for (int i = 255; i > 0; --i) {
+        QByteArray ba;
+        ba.resize(i);
+        qint64 thisRead = ringBuffer.read(ba.data(), i);
+        QCOMPARE(thisRead, qint64(i));
+        QVERIFY(ba.count(char(i)) == i);
+    }
+    QVERIFY(ringBuffer.size() == 0);
+}
+
 void tst_QRingBuffer::chop()
 {
     QRingBuffer ringBuffer;