backends/libinput: Rework Device getter

libinput_device_get_user_data() can be used to get the associated Device
object with libinput_device. That way, we won't need to maintain a
private list of all input devices.

autotests/libinput/device_test.cpp

@@ -26,7 +26,6 @@ class TestLibinputDevice : public QObject
     Q_OBJECT
 private Q_SLOTS:
     void initTestCase();
-    void testStaticGetter();
     void testDeviceType_data();
     void testDeviceType();
     void testGestureSupport_data();
@@ -181,48 +180,6 @@ void TestLibinputDevice::initTestCase()
     QDBusConnection::sessionBus().registerService(QStringLiteral("org.kde.kwin.tests.libinputdevice"));
 }
 
-void TestLibinputDevice::testStaticGetter()
-{
-    // this test verifies that the static getter for Device works as expected
-    QVERIFY(Device::devices().isEmpty());
-
-    // create some device
-    libinput_device device1;
-    libinput_device device2;
-    // at the moment not yet known to Device
-    QVERIFY(!Device::getDevice(&device1));
-    QVERIFY(!Device::getDevice(&device2));
-    QVERIFY(Device::devices().isEmpty());
-
-    // now create a Device for one
-    Device *d1 = new Device(&device1);
-    QCOMPARE(Device::devices().count(), 1);
-    QCOMPARE(Device::devices().first(), d1);
-    QCOMPARE(Device::getDevice(&device1), d1);
-    QVERIFY(!Device::getDevice(&device2));
-
-    // and a second Device
-    Device *d2 = new Device(&device2);
-    QCOMPARE(Device::devices().count(), 2);
-    QCOMPARE(Device::devices().first(), d1);
-    QCOMPARE(Device::devices().last(), d2);
-    QCOMPARE(Device::getDevice(&device1), d1);
-    QCOMPARE(Device::getDevice(&device2), d2);
-
-    // now delete d1
-    delete d1;
-    QCOMPARE(Device::devices().count(), 1);
-    QCOMPARE(Device::devices().first(), d2);
-    QCOMPARE(Device::getDevice(&device2), d2);
-    QVERIFY(!Device::getDevice(&device1));
-
-    // and delete d2
-    delete d2;
-    QVERIFY(!Device::getDevice(&device1));
-    QVERIFY(!Device::getDevice(&device2));
-    QVERIFY(Device::devices().isEmpty());
-}
-
 void TestLibinputDevice::testDeviceType_data()
 {
     QTest::addColumn<bool>("keyboard");

autotests/libinput/mock_libinput.cpp

@@ -956,3 +956,14 @@ void libinput_device_led_update(struct libinput_device *device,
     Q_UNUSED(device)
     Q_UNUSED(leds)
 }
+
+void libinput_device_set_user_data(struct libinput_device *device, void *user_data)
+{
+    device->userData = user_data;
+}
+
+void *
+libinput_device_get_user_data(struct libinput_device *device)
+{
+    return device->userData;
+}

autotests/libinput/mock_libinput.h

@@ -19,6 +19,7 @@
 
 struct libinput_device
 {
+    void *userData = nullptr;
     bool keyboard = false;
     bool pointer = false;
     bool touch = false;

src/backends/libinput/device.cpp

@@ -77,20 +77,6 @@ static bool checkAlphaNumericKeyboard(libinput_device *device)
     return true;
 }
 
-QVector<Device *> Device::s_devices;
-
-Device *Device::getDevice(libinput_device *native)
-{
-    auto it = std::find_if(s_devices.constBegin(), s_devices.constEnd(),
-                           [native](const Device *d) {
-                               return d->device() == native;
-                           });
-    if (it != s_devices.constEnd()) {
-        return *it;
-    }
-    return nullptr;
-}
-
 enum class ConfigKey {
     Enabled,
     LeftHanded,
@@ -336,6 +322,7 @@ Device::Device(libinput_device *device, QObject *parent)
     , m_clickMethod(libinput_device_config_click_get_method(m_device))
 {
     libinput_device_ref(m_device);
+    libinput_device_set_user_data(m_device, this);
 
     qreal width = 0;
     qreal height = 0;
@@ -385,7 +372,6 @@ Device::Device(libinput_device *device, QObject *parent)
 
     qDBusRegisterMetaType<QMatrix4x4>();
 
-    s_devices << this;
     QDBusConnection::sessionBus().registerObject(QStringLiteral("/org/kde/KWin/InputDevice/") + m_sysName,
                                                  QStringLiteral("org.kde.KWin.InputDevice"),
                                                  this,
@@ -394,11 +380,16 @@ Device::Device(libinput_device *device, QObject *parent)
 
 Device::~Device()
 {
-    s_devices.removeOne(this);
     QDBusConnection::sessionBus().unregisterObject(QStringLiteral("/org/kde/KWin/InputDevice/") + m_sysName);
+    libinput_device_set_user_data(m_device, nullptr);
     libinput_device_unref(m_device);
 }
 
+Device *Device::get(libinput_device *native)
+{
+    return static_cast<Device *>(libinput_device_get_user_data(native));
+}
+
 template<typename T>
 void Device::writeEntry(const ConfigKey &key, const T &value)
 {

src/backends/libinput/device.h

@@ -619,17 +619,10 @@ public:
     LEDs leds() const override;
     void setLeds(LEDs leds) override;
 
-    /**
-     * All created Devices
-     */
-    static QVector<Device *> devices()
-    {
-        return s_devices;
-    }
     /**
      * Gets the Device for @p native. @c null if there is no Device for @p native.
      */
-    static Device *getDevice(libinput_device *native);
+    static Device *get(libinput_device *native);
 
 Q_SIGNALS:
     void tapButtonMapChanged();
@@ -736,7 +729,6 @@ private:
     enum libinput_config_click_method m_clickMethod;
 
     LEDs m_leds;
-    static QVector<Device *> s_devices;
 };
 
 }

src/backends/libinput/events.cpp

@@ -83,7 +83,7 @@ Event::~Event()
 Device *Event::device() const
 {
     if (!m_device) {
-        m_device = Device::getDevice(libinput_event_get_device(m_event));
+        m_device = Device::get(libinput_event_get_device(m_event));
     }
     return m_device;
 }