[effects] Delay creation of EffectFrames in WindowGeometryEffect

Summary:
Without Xwayland KWin starts so fast that the creation of the EffectFrame
triggers a crash in the Wayland integration as the KWin internal
connection isn't fully setup.

To workaround this crash the creation of the EffectFrame is delayed till
the first usage. It doesn't make sense to try to fix the actual crash as
it would require to defer the creation of all Effects.

Test Plan: New test case added which crashes without this fix.

Reviewers: #kwin, #plasma

Subscribers: plasma-devel, kwin

Tags: #kwin

Differential Revision: https://phabricator.kde.org/D8821

autotests/integration/effects/CMakeLists.txt

@@ -3,3 +3,4 @@ if (XCB_ICCCM_FOUND)
     integrationTest(NAME testSlidingPopups SRCS slidingpopups_test.cpp LIBS XCB::ICCCM)
 endif()
 integrationTest(NAME testFade SRCS fade_test.cpp)
+integrationTest(WAYLAND_ONLY NAME testEffectWindowGeometry SRCS windowgeometry_test.cpp)

autotests/integration/effects/windowgeometry_test.cpp

@@ -0,0 +1,99 @@
+/********************************************************************
+KWin - the KDE window manager
+This file is part of the KDE project.
+
+Copyright (C) 2017 Martin Flöser <mgraesslin@kde.org>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*********************************************************************/
+#include "kwin_wayland_test.h"
+#include "composite.h"
+#include "effects.h"
+#include "effectloader.h"
+#include "cursor.h"
+#include "platform.h"
+#include "shell_client.h"
+#include "wayland_server.h"
+#include "workspace.h"
+#include "effect_builtins.h"
+
+#include <KConfigGroup>
+
+#include <KWayland/Client/buffer.h>
+#include <KWayland/Client/shell.h>
+#include <KWayland/Client/surface.h>
+
+using namespace KWin;
+using namespace KWayland::Client;
+static const QString s_socketName = QStringLiteral("wayland_test_effects_windowgeometry-0");
+
+class WindowGeometryTest : public QObject
+{
+Q_OBJECT
+private Q_SLOTS:
+    void initTestCase();
+    void init();
+    void cleanup();
+
+    void testStartup();
+};
+
+void WindowGeometryTest::initTestCase()
+{
+    qRegisterMetaType<KWin::ShellClient*>();
+    qRegisterMetaType<KWin::AbstractClient*>();
+    qRegisterMetaType<KWin::Effect*>();
+    QSignalSpy workspaceCreatedSpy(kwinApp(), &Application::workspaceCreated);
+    QVERIFY(workspaceCreatedSpy.isValid());
+    kwinApp()->platform()->setInitialWindowSize(QSize(1280, 1024));
+    QVERIFY(waylandServer()->init(s_socketName.toLocal8Bit()));
+
+    // disable all effects - we don't want to have it interact with the rendering
+    auto config = KSharedConfig::openConfig(QString(), KConfig::SimpleConfig);
+    KConfigGroup plugins(config, QStringLiteral("Plugins"));
+    ScriptedEffectLoader loader;
+    const auto builtinNames = BuiltInEffects::availableEffectNames() << loader.listOfKnownEffects();
+    for (QString name : builtinNames) {
+        plugins.writeEntry(name + QStringLiteral("Enabled"), false);
+    }
+    plugins.writeEntry(BuiltInEffects::nameForEffect(BuiltInEffect::WindowGeometry) + QStringLiteral("Enabled"), true);
+
+    config->sync();
+    kwinApp()->setConfig(config);
+
+    qputenv("KWIN_EFFECTS_FORCE_ANIMATIONS", "1");
+    kwinApp()->start();
+    QVERIFY(workspaceCreatedSpy.wait());
+    QVERIFY(KWin::Compositor::self());
+}
+
+void WindowGeometryTest::init()
+{
+    QVERIFY(Test::setupWaylandConnection());
+}
+
+void WindowGeometryTest::cleanup()
+{
+    Test::destroyWaylandConnection();
+}
+
+void WindowGeometryTest::testStartup()
+{
+    // just a test to load the effect to verify it doesn't crash
+    EffectsHandlerImpl *e = static_cast<EffectsHandlerImpl*>(effects);
+    QVERIFY(e->isEffectLoaded(BuiltInEffects::nameForEffect(BuiltInEffect::WindowGeometry)));
+}
+
+WAYLANDTEST_MAIN(WindowGeometryTest)
+#include "windowgeometry_test.moc"

effects/windowgeometry/windowgeometry.cpp

@@ -48,15 +48,6 @@ WindowGeometry::WindowGeometry()
                         " %3 and %4 are the resp. increments - avoid reformatting or suffixes like 'px'", \
                         "X: %1 (%3)\nY: %2 (%4)"
     reconfigure(ReconfigureAll);
-    QFont fnt; fnt.setBold(true); fnt.setPointSize(12);
-    for (int i = 0; i < 3; ++i) {
-        myMeasure[i] = effects->effectFrame(EffectFrameUnstyled, false);
-        myMeasure[i]->setFont(fnt);
-    }
-    myMeasure[0]->setAlignment(Qt::AlignLeft | Qt::AlignTop);
-    myMeasure[1]->setAlignment(Qt::AlignCenter);
-    myMeasure[2]->setAlignment(Qt::AlignRight | Qt::AlignBottom);
-
     QAction* a = new QAction(this);
     a->setObjectName(QStringLiteral("WindowGeometry"));
     a->setText(i18n("Toggle window geometry display (effect only)"));
@@ -78,6 +69,22 @@ WindowGeometry::~WindowGeometry()
         delete myMeasure[i];
 }
 
+void WindowGeometry::createFrames()
+{
+    if (myMeasure[0]) {
+        return;
+    }
+    QFont fnt; fnt.setBold(true); fnt.setPointSize(12);
+    for (int i = 0; i < 3; ++i) {
+        myMeasure[i] = effects->effectFrame(EffectFrameUnstyled, false);
+        myMeasure[i]->setFont(fnt);
+    }
+    myMeasure[0]->setAlignment(Qt::AlignLeft | Qt::AlignTop);
+    myMeasure[1]->setAlignment(Qt::AlignCenter);
+    myMeasure[2]->setAlignment(Qt::AlignRight | Qt::AlignBottom);
+
+}
+
 void WindowGeometry::reconfigure(ReconfigureFlags)
 {
     WindowGeometryConfiguration::self()->read();
@@ -97,6 +104,7 @@ void WindowGeometry::paintScreen(int mask, QRegion region, ScreenPaintData &data
 void WindowGeometry::toggle()
 {
     iAmActivated = !iAmActivated;
+    createFrames();
 }
 
 void WindowGeometry::slotWindowStartUserMovedResized(EffectWindow *w)
@@ -108,6 +116,7 @@ void WindowGeometry::slotWindowStartUserMovedResized(EffectWindow *w)
     if (w->isUserMove() && !iHandleMoves)
         return;
 
+    createFrames();
     iAmActive = true;
     myResizeWindow = w;
     myOriginalGeometry = w->geometry();

effects/windowgeometry/windowgeometry.h

@@ -59,8 +59,9 @@ private Q_SLOTS:
     void slotWindowFinishUserMovedResized(KWin::EffectWindow *w);
     void slotWindowStepUserMovedResized(KWin::EffectWindow *w, const QRect &geometry);
 private:
+    void createFrames();
     EffectWindow *myResizeWindow;
-    EffectFrame *myMeasure[3];
+    EffectFrame *myMeasure[3] = {nullptr, nullptr, nullptr};
     QRect myOriginalGeometry, myCurrentGeometry;
     QRect myExtraDirtyArea;
     bool iAmActive, iAmActivated, iHandleMoves, iHandleResizes;