Ensure that WaylandServer::shellClientAdded only gets emitted once

Summary:
When a shell client got mapped, unmapped and mapped again we emitted
the shellClientAdded signal in WaylandServer again. This resulted in
e.g. Workspace, EffectsHandler, etc. to start managing the window again.
This can be a reason for problems we see with such windows like the
Plasma panel dialog when opened the second time.

Test Plan:
Needs extensive testing on real world system as that changes
behavior now.

Reviewers: #kwin, #plasma_on_wayland

Differential Revision: https://phabricator.kde.org/D1784

autotests/wayland/CMakeLists.txt

@@ -207,3 +207,12 @@ add_executable(testMaximized ${testMaximized_SRCS})
 target_link_libraries( testMaximized kwin Qt5::Test)
 add_test(kwin-testMaximized testMaximized)
 ecm_mark_as_test(testMaximized)
+
+########################################################
+# Shell Client Test
+########################################################
+set( testShellClient_SRCS shell_client_test.cpp kwin_wayland_test.cpp )
+add_executable(testShellClient ${testShellClient_SRCS})
+target_link_libraries( testShellClient kwin Qt5::Test)
+add_test(kwin-testShellClient testShellClient)
+ecm_mark_as_test(testShellClient)

autotests/wayland/shell_client_test.cpp

@@ -0,0 +1,208 @@
+/********************************************************************
+KWin - the KDE window manager
+This file is part of the KDE project.
+
+Copyright (C) 2016 Martin Gräßlin <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 "cursor.h"
+#include "platform.h"
+#include "shell_client.h"
+#include "screens.h"
+#include "wayland_server.h"
+
+#include <KWayland/Client/connection_thread.h>
+#include <KWayland/Client/compositor.h>
+#include <KWayland/Client/event_queue.h>
+#include <KWayland/Client/registry.h>
+#include <KWayland/Client/shell.h>
+#include <KWayland/Client/shm_pool.h>
+#include <KWayland/Client/surface.h>
+
+#include <KWayland/Server/shell_interface.h>
+
+#include <QThread>
+
+using namespace KWin;
+using namespace KWayland::Client;
+
+static const QString s_socketName = QStringLiteral("wayland_test_kwin_shell_client-0");
+
+class TestShellClient : public QObject
+{
+    Q_OBJECT
+private Q_SLOTS:
+    void initTestCase();
+    void init();
+    void cleanup();
+
+    void testMapUnmapMap();
+
+private:
+    KWayland::Client::Compositor *m_compositor = nullptr;
+    Shell *m_shell = nullptr;
+    ShmPool *m_shm = nullptr;
+    EventQueue *m_queue = nullptr;
+    ConnectionThread *m_connection = nullptr;
+    QThread *m_thread = nullptr;
+};
+
+void TestShellClient::initTestCase()
+{
+    qRegisterMetaType<KWin::ShellClient*>();
+    qRegisterMetaType<KWin::AbstractClient*>();
+    QSignalSpy workspaceCreatedSpy(kwinApp(), &Application::workspaceCreated);
+    QVERIFY(workspaceCreatedSpy.isValid());
+    kwinApp()->platform()->setInitialWindowSize(QSize(1280, 1024));
+    QMetaObject::invokeMethod(kwinApp()->platform(), "setOutputCount", Qt::DirectConnection, Q_ARG(int, 2));
+    waylandServer()->init(s_socketName.toLocal8Bit());
+
+    kwinApp()->start();
+    QVERIFY(workspaceCreatedSpy.wait());
+    QCOMPARE(screens()->count(), 2);
+    QCOMPARE(screens()->geometry(0), QRect(0, 0, 1280, 1024));
+    QCOMPARE(screens()->geometry(1), QRect(1280, 0, 1280, 1024));
+    waylandServer()->initWorkspace();
+}
+
+void TestShellClient::init()
+{
+    // setup connection
+    m_connection = new ConnectionThread;
+    QSignalSpy connectedSpy(m_connection, &ConnectionThread::connected);
+    QVERIFY(connectedSpy.isValid());
+    m_connection->setSocketName(s_socketName);
+
+    m_thread = new QThread(this);
+    m_connection->moveToThread(m_thread);
+    m_thread->start();
+
+    m_connection->initConnection();
+    QVERIFY(connectedSpy.wait());
+
+    m_queue = new EventQueue(this);
+    QVERIFY(!m_queue->isValid());
+    m_queue->setup(m_connection);
+    QVERIFY(m_queue->isValid());
+
+    Registry registry;
+    registry.setEventQueue(m_queue);
+    QSignalSpy allAnnounced(&registry, &Registry::interfacesAnnounced);
+    QVERIFY(allAnnounced.isValid());
+    registry.create(m_connection->display());
+    QVERIFY(registry.isValid());
+    registry.setup();
+    QVERIFY(allAnnounced.wait());
+
+    m_compositor = registry.createCompositor(registry.interface(Registry::Interface::Compositor).name,
+                                             registry.interface(Registry::Interface::Compositor).version,
+                                             this);
+    QVERIFY(m_compositor->isValid());
+    m_shm = registry.createShmPool(registry.interface(Registry::Interface::Shm).name,
+                                   registry.interface(Registry::Interface::Shm).version,
+                                   this);
+    QVERIFY(m_shm->isValid());
+    m_shell = registry.createShell(registry.interface(Registry::Interface::Shell).name,
+                                   registry.interface(Registry::Interface::Shell).version,
+                                   this);
+    QVERIFY(m_shell->isValid());
+
+    screens()->setCurrent(0);
+    KWin::Cursor::setPos(QPoint(1280, 512));
+}
+
+void TestShellClient::cleanup()
+{
+#define CLEANUP(name) \
+    if (name) { \
+        delete name; \
+        name = nullptr; \
+    }
+    CLEANUP(m_compositor)
+    CLEANUP(m_shm)
+    CLEANUP(m_shell)
+    CLEANUP(m_queue)
+
+    if (m_connection) {
+        m_connection->deleteLater();
+        m_connection = nullptr;
+    }
+    if (m_thread) {
+        m_thread->quit();
+        m_thread->wait();
+        delete m_thread;
+        m_thread = nullptr;
+    }
+#undef CLEANUP
+}
+
+void TestShellClient::testMapUnmapMap()
+{
+    // this test verifies that mapping a previously mapped window works correctly
+    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
+    QVERIFY(clientAddedSpy.isValid());
+
+    QScopedPointer<Surface> surface(m_compositor->createSurface());
+    QScopedPointer<ShellSurface> shellSurface(m_shell->createSurface(surface.data()));
+
+    // now let's render
+    QImage img(QSize(100, 50), QImage::Format_ARGB32);
+    img.fill(Qt::blue);
+    surface->attachBuffer(m_shm->createBuffer(img));
+    surface->damage(QRect(0, 0, 100, 50));
+    surface->commit(Surface::CommitFlag::None);
+
+    QVERIFY(clientAddedSpy.isEmpty());
+    QVERIFY(clientAddedSpy.wait());
+    auto client = clientAddedSpy.first().first().value<ShellClient*>();
+    QVERIFY(client);
+    QVERIFY(client->isShown(true));
+
+    // now unmap
+    QSignalSpy hiddenSpy(client, &ShellClient::windowHidden);
+    QVERIFY(hiddenSpy.isValid());
+    QSignalSpy windowClosedSpy(client, &ShellClient::windowClosed);
+    QVERIFY(windowClosedSpy.isValid());
+    surface->attachBuffer(Buffer::Ptr());
+    surface->commit(Surface::CommitFlag::None);
+    QVERIFY(hiddenSpy.wait());
+    QVERIFY(windowClosedSpy.isEmpty());
+
+    QSignalSpy windowShownSpy(client, &ShellClient::windowShown);
+    QVERIFY(windowShownSpy.isValid());
+    surface->attachBuffer(m_shm->createBuffer(img));
+    surface->damage(QRect(0, 0, 100, 50));
+    surface->commit(Surface::CommitFlag::None);
+    QCOMPARE(clientAddedSpy.count(), 1);
+    QVERIFY(windowShownSpy.wait());
+    QCOMPARE(windowShownSpy.count(), 1);
+    QCOMPARE(clientAddedSpy.count(), 1);
+
+    // let's unmap again
+    surface->attachBuffer(Buffer::Ptr());
+    surface->commit(Surface::CommitFlag::None);
+    QVERIFY(hiddenSpy.wait());
+    QCOMPARE(hiddenSpy.count(), 2);
+    QVERIFY(windowClosedSpy.isEmpty());
+
+    shellSurface.reset();
+    surface.reset();
+    QVERIFY(windowClosedSpy.wait());
+    QCOMPARE(windowClosedSpy.count(), 1);
+}
+
+WAYLANDTEST_MAIN(TestShellClient)
+#include "shell_client_test.moc"

wayland_server.cpp

@@ -167,11 +167,7 @@ void WaylandServer::init(const QByteArray &socketName, InitalizationFlags flags)
             if (client->readyForPainting()) {
                 emit shellClientAdded(client);
             } else {
-                connect(client, &ShellClient::windowShown, this,
-                    [this, client] {
-                        emit shellClientAdded(client);
-                    }
-                );
+                connect(client, &ShellClient::windowShown, this, &WaylandServer::shellClientShown);
             }
         }
     );
@@ -249,6 +245,17 @@ void WaylandServer::init(const QByteArray &socketName, InitalizationFlags flags)
     m_display->createSubCompositor(m_display)->create();
 }
 
+void WaylandServer::shellClientShown(Toplevel *t)
+{
+    ShellClient *c = dynamic_cast<ShellClient*>(t);
+    if (!c) {
+        qCWarning(KWIN_CORE) << "Failed to cast a Toplevel which is supposed to be a ShellClient to ShellClient";
+        return;
+    }
+    disconnect(c, &ShellClient::windowShown, this, &WaylandServer::shellClientShown);
+    emit shellClientAdded(c);
+}
+
 void WaylandServer::initWorkspace()
 {
     if (m_windowManagement) {

wayland_server.h

@@ -59,6 +59,7 @@ namespace KWin
 class ShellClient;
 
 class AbstractClient;
+class Toplevel;
 
 class KWIN_EXPORT WaylandServer : public QObject
 {
@@ -159,6 +160,7 @@ Q_SIGNALS:
     void terminatingInternalClientConnection();
 
 private:
+    void shellClientShown(Toplevel *t);
     void initOutputs();
     quint16 createClientId(KWayland::Server::ClientConnection *c);
     void destroyInternalConnection();