Release pixmap cache data to avoid leaking memory

Previously, QDeclarativePixmapStore did not release cache entries on
destruction.  This commit ensures that all cache entries are released
properly.  Note that while any QDeclarativePixmapData which contains
a texture will be deleted, the texture itself will be scheduled for
cleanup rather than released directly.

Task-number: QTBUG-22742
Change-Id: I62ddf57f2b55b732ab369321eb9ed0d7af01c135
Reviewed-by: Martin Jones <martin.jones@nokia.com>

2 files changed, 80 insertions, 11 deletions

diff --git a/tests/auto/declarative/qdeclarativepixmapcache/data/dataLeak.qml b/tests/auto/declarative/qdeclarativepixmapcache/data/dataLeak.qml
new file mode 100644
index 0000000000..724ce5d816
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativepixmapcache/data/dataLeak.qml
@@ -0,0 +1,18 @@
+import QtQuick 2.0
+
+Item {
+    id: root
+    width: 800
+    height: 800
+
+    Image {
+        id: i1
+        source: "exists1.png";
+        anchors.top: parent.top;
+    }
+    Image {
+        id: i2
+        source: "exists2.png"
+        anchors.top: i1.bottom;
+    }
+}
diff --git a/tests/auto/declarative/qdeclarativepixmapcache/tst_qdeclarativepixmapcache.cpp b/tests/auto/declarative/qdeclarativepixmapcache/tst_qdeclarativepixmapcache.cpp
index 5224de3e56..1bd0e70ddb 100644
--- a/tests/auto/declarative/qdeclarativepixmapcache/tst_qdeclarativepixmapcache.cpp
+++ b/tests/auto/declarative/qdeclarativepixmapcache/tst_qdeclarativepixmapcache.cpp
@@ -44,6 +44,7 @@
 #include <QtDeclarative/qdeclarativeengine.h>
 #include <QtDeclarative/qdeclarativeimageprovider.h>
 #include <QNetworkReply>
+#include "../shared/util.h"
 #include "testhttpserver.h"
 
 #ifndef QT_NO_CONCURRENT
@@ -51,15 +52,19 @@
 #include <qfuture.h>
 #endif
 
+inline QUrl TEST_FILE(const QString &filename)
+{
+    return QUrl::fromLocalFile(TESTDATA(filename));
+}
+
 class tst_qdeclarativepixmapcache : public QObject
 {
     Q_OBJECT
 public:
     tst_qdeclarativepixmapcache() :
-        thisfile(QUrl::fromLocalFile(QCoreApplication::applicationFilePath())),
         server(14452)
     {
-        server.serveDirectory(QCoreApplication::applicationDirPath() + "/data/http");
+        server.serveDirectory(TESTDATA("http"));
     }
 
 private slots:
@@ -74,13 +79,12 @@ private slots:
     void networkCrash();
 #endif
     void lockingCrash();
+    void dataLeak();
 private:
     QDeclarativeEngine engine;
-    QUrl thisfile;
     TestHTTPServer server;
 };
 
-
 static int slotters=0;
 
 class Slotter : public QObject
@@ -121,8 +125,8 @@ void tst_qdeclarativepixmapcache::single_data()
     QTest::addColumn<bool>("neterror");
 
     // File URLs are optimized
-    QTest::newRow("local") << thisfile.resolved(QUrl("data/exists.png")) << localfile_optimized << true << false;
-    QTest::newRow("local") << thisfile.resolved(QUrl("data/notexists.png")) << localfile_optimized << false << false;
+    QTest::newRow("local") << TEST_FILE("exists.png") << localfile_optimized << true << false;
+    QTest::newRow("local") << TEST_FILE("notexists.png") << localfile_optimized << false << false;
     QTest::newRow("remote") << QUrl("http://127.0.0.1:14452/exists.png") << false << true << false;
     QTest::newRow("remote") << QUrl("http://127.0.0.1:14452/notexists.png") << false << false << true;
 }
@@ -185,8 +189,8 @@ void tst_qdeclarativepixmapcache::parallel_data()
     QTest::addColumn<int>("cancel"); // which one to cancel
 
     QTest::newRow("local")
-            << thisfile.resolved(QUrl("data/exists1.png"))
-            << thisfile.resolved(QUrl("data/exists2.png"))
+            << TEST_FILE("exists1.png")
+            << TEST_FILE("exists2.png")
             << (localfile_optimized ? 2 : 0)
             << -1;
 
@@ -282,7 +286,7 @@ void tst_qdeclarativepixmapcache::parallel()
 void tst_qdeclarativepixmapcache::massive()
 {
     QDeclarativeEngine engine;
-    QUrl url = thisfile.resolved(QUrl("data/massive.png"));
+    QUrl url = TEST_FILE("massive.png");
 
     // Confirm that massive images remain in the cache while they are
     // in use by the application.
@@ -360,7 +364,7 @@ void createNetworkServer()
 {
    QEventLoop eventLoop;
    TestHTTPServer server(14453);
-   server.serveDirectory(QCoreApplication::applicationDirPath() + "/data/http");
+   server.serveDirectory(TESTDATA("http"));
    QTimer::singleShot(100, &eventLoop, SLOT(quit()));
    eventLoop.exec();
 }
@@ -388,7 +392,7 @@ void tst_qdeclarativepixmapcache::networkCrash()
 void tst_qdeclarativepixmapcache::lockingCrash()
 {
     TestHTTPServer server(14453);
-    server.serveDirectory(QCoreApplication::applicationDirPath() + "/data/http", TestHTTPServer::Delay);
+    server.serveDirectory(TESTDATA("http"), TestHTTPServer::Delay);
 
     {
         QDeclarativePixmap* p = new QDeclarativePixmap;
@@ -402,6 +406,53 @@ void tst_qdeclarativepixmapcache::lockingCrash()
     }
 }
 
+#include <QQuickView>
+class DataLeakView : public QQuickView
+{
+    Q_OBJECT
+
+public:
+    explicit DataLeakView() : QQuickView()
+    {
+        setSource(TEST_FILE("dataLeak.qml"));
+    }
+
+    void showFor2Seconds()
+    {
+        showFullScreen();
+        QTimer::singleShot(2000, this, SIGNAL(ready()));
+    }
+
+signals:
+    void ready();
+};
+
+// QTBUG-22742
+Q_GLOBAL_STATIC(QDeclarativePixmap, dataLeakPixmap)
+void tst_qdeclarativepixmapcache::dataLeak()
+{
+    // Should not leak cached QDeclarativePixmapData.
+    // Unfortunately, since the QDeclarativePixmapStore
+    // is a global static, and it releases the cache
+    // entries on dtor (application exit), we must use
+    // valgrind to determine whether it leaks or not.
+    QDeclarativePixmap *p1 = new QDeclarativePixmap;
+    QDeclarativePixmap *p2 = new QDeclarativePixmap;
+    {
+        QScopedPointer<DataLeakView> test(new DataLeakView);
+        test->showFor2Seconds();
+        dataLeakPixmap()->load(test->engine(), TEST_FILE("exists.png"));
+        p1->load(test->engine(), TEST_FILE("exists.png"));
+        p2->load(test->engine(), TEST_FILE("exists2.png"));
+        QTest::qWait(2005); // 2 seconds + a few more millis.
+    }
+
+    // When the (global static) dataLeakPixmap is deleted, it
+    // shouldn't attempt to dereference a QDeclarativePixmapData
+    // which has been deleted by the QDeclarativePixmapStore
+    // destructor.
+}
+
 QTEST_MAIN(tst_qdeclarativepixmapcache)
 
 #include "tst_qdeclarativepixmapcache.moc"