Support enabling numlock on startup

Summary:
This change brings improved num lock support to KWin. The modifier state
is read and also mapped to Qt::KeyboardModifiers. Furthermore the input
config is read and the NumLock key is evaluated. If the requested state
does not match the current num lock state the state is swapped.

BUG: 375708
FIXED-IN: 5.15

Test Plan: New unit test added, no manual test due to lack of hardware

Subscribers: kwin

Tags: #kwin

Differential Revision: https://phabricator.kde.org/D16428

autotests/integration/keyboard_layout_test.cpp

@@ -60,6 +60,7 @@ private Q_SLOTS:
     void testVirtualDesktopPolicy();
     void testWindowPolicy();
     void testApplicationPolicy();
+    void testNumLock();
 
 private:
     void reconfigureLayouts();
@@ -83,6 +84,7 @@ void KeyboardLayoutTest::initTestCase()
 
     kwinApp()->setConfig(KSharedConfig::openConfig(QString(), KConfig::SimpleConfig));
     kwinApp()->setKxkbConfig(KSharedConfig::openConfig(QString(), KConfig::SimpleConfig));
+    kwinApp()->setInputConfig(KSharedConfig::openConfig(QString(), KConfig::SimpleConfig));
 
     kwinApp()->start();
     QVERIFY(workspaceCreatedSpy.wait());
@@ -457,5 +459,46 @@ void KeyboardLayoutTest::testApplicationPolicy()
     QTRY_COMPARE(xkb->layoutName(), QStringLiteral("German (Neo 2)"));
 }
 
+void KeyboardLayoutTest::testNumLock()
+{
+    qputenv("KWIN_FORCE_NUM_LOCK_EVALUATION", "1");
+    auto xkb = input()->keyboard()->xkb();
+    // by default not set
+    QVERIFY(!xkb->modifiers().testFlag(Qt::KeypadModifier));
+    quint32 timestamp = 0;
+    kwinApp()->platform()->keyboardKeyPressed(KEY_NUMLOCK, timestamp++);
+    kwinApp()->platform()->keyboardKeyReleased(KEY_NUMLOCK, timestamp++);
+    // now it should be on
+    QVERIFY(xkb->modifiers().testFlag(Qt::KeypadModifier));
+    // and back to off
+    kwinApp()->platform()->keyboardKeyPressed(KEY_NUMLOCK, timestamp++);
+    kwinApp()->platform()->keyboardKeyReleased(KEY_NUMLOCK, timestamp++);
+    QVERIFY(!xkb->modifiers().testFlag(Qt::KeypadModifier));
+
+    // let's reconfigure to enable through config
+    auto group = kwinApp()->inputConfig()->group("Keyboard");
+    group.writeEntry("NumLock", 0);
+    group.sync();
+    xkb->reconfigure();
+    // now it should be on
+    QVERIFY(xkb->modifiers().testFlag(Qt::KeypadModifier));
+    // pressing should result in it being off
+    kwinApp()->platform()->keyboardKeyPressed(KEY_NUMLOCK, timestamp++);
+    kwinApp()->platform()->keyboardKeyReleased(KEY_NUMLOCK, timestamp++);
+    QVERIFY(!xkb->modifiers().testFlag(Qt::KeypadModifier));
+
+    // pressing again should enable it
+    kwinApp()->platform()->keyboardKeyPressed(KEY_NUMLOCK, timestamp++);
+    kwinApp()->platform()->keyboardKeyReleased(KEY_NUMLOCK, timestamp++);
+    QVERIFY(xkb->modifiers().testFlag(Qt::KeypadModifier));
+
+    // now reconfigure to disable on load
+    group.writeEntry("NumLock", 1);
+    group.sync();
+    xkb->reconfigure();
+    QVERIFY(!xkb->modifiers().testFlag(Qt::KeypadModifier));
+}
+
+
 WAYLANDTEST_MAIN(KeyboardLayoutTest)
 #include "keyboard_layout_test.moc"

keyboard_input.cpp

@@ -111,6 +111,7 @@ void KeyboardInputRedirection::init()
     Q_ASSERT(!m_inited);
     m_inited = true;
     const auto config = kwinApp()->kxkbConfig();
+    m_xkb->setNumLockConfig(kwinApp()->inputConfig());
     m_xkb->setConfig(config);
 
     m_input->installInputEventSpy(new KeyStateChangedSpy(m_input));

xkb.cpp

@@ -34,6 +34,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 // system
 #include <sys/mman.h>
 #include <unistd.h>
+#include <bitset>
 
 Q_LOGGING_CATEGORY(KWIN_XKB, "kwin_xkbcommon", QtCriticalMsg)
 
@@ -75,6 +76,7 @@ Xkb::Xkb(QObject *parent)
     , m_controlModifier(0)
     , m_altModifier(0)
     , m_metaModifier(0)
+    , m_numModifier(0)
     , m_numLock(0)
     , m_capsLock(0)
     , m_scrollLock(0)
@@ -214,6 +216,7 @@ void Xkb::installKeymap(int fd, uint32_t size)
         qCDebug(KWIN_XKB) << "Could not map keymap from file";
         return;
     }
+    m_ownership = Ownership::Client;
     updateKeymap(keymap);
 }
 
@@ -238,6 +241,7 @@ void Xkb::updateKeymap(xkb_keymap *keymap)
     m_controlModifier = xkb_keymap_mod_get_index(m_keymap, XKB_MOD_NAME_CTRL);
     m_altModifier     = xkb_keymap_mod_get_index(m_keymap, XKB_MOD_NAME_ALT);
     m_metaModifier    = xkb_keymap_mod_get_index(m_keymap, XKB_MOD_NAME_LOGO);
+    m_numModifier     = xkb_keymap_mod_get_index(m_keymap, XKB_MOD_NAME_NUM);
 
     m_numLock         = xkb_keymap_led_get_index(m_keymap, XKB_LED_NAME_NUM);
     m_capsLock        = xkb_keymap_led_get_index(m_keymap, XKB_LED_NAME_CAPS);
@@ -249,8 +253,29 @@ void Xkb::updateKeymap(xkb_keymap *keymap)
     m_modifierState.latched = xkb_state_serialize_mods(m_state, xkb_state_component(XKB_STATE_MODS_LATCHED));
     m_modifierState.locked = xkb_state_serialize_mods(m_state, xkb_state_component(XKB_STATE_MODS_LOCKED));
 
+    static bool s_startup = true;
+    if (s_startup || qEnvironmentVariableIsSet("KWIN_FORCE_NUM_LOCK_EVALUATION")) {
+        s_startup = false;
+        if (m_ownership == Ownership::Server && m_numModifier != XKB_MOD_INVALID && m_numLockConfig) {
+            const KConfigGroup config = m_numLockConfig->group("Keyboard");
+            // STATE_ON = 0,  STATE_OFF = 1, STATE_UNCHANGED = 2, see plasma-desktop/kcms/keyboard/kcmmisc.h
+            const auto setting = config.readEntry("NumLock", 2);
+            const bool numLockIsOn = xkb_state_mod_index_is_active(m_state, m_numModifier, XKB_STATE_MODS_LOCKED);
+            if ((setting == 0 && !numLockIsOn) || (setting == 1 && numLockIsOn)) {
+                std::bitset<sizeof(xkb_mod_mask_t)*8> mask{m_modifierState.locked};
+                if (mask.size() > m_numModifier) {
+                    mask[m_numModifier] = (setting == 0);
+                    m_modifierState.locked = mask.to_ulong();
+                    xkb_state_update_mask(m_state, m_modifierState.depressed, m_modifierState.latched, m_modifierState.locked, 0, 0, m_currentLayout);
+                    m_modifierState.locked = xkb_state_serialize_mods(m_state, xkb_state_component(XKB_STATE_MODS_LOCKED));
+                }
+            }
+        }
+    }
+
     createKeymapFile();
     forwardModifiers();
+    updateModifiers();
 }
 
 void Xkb::createKeymapFile()
@@ -344,6 +369,9 @@ void Xkb::updateModifiers()
     if (xkb_state_mod_index_is_active(m_state, m_metaModifier, XKB_STATE_MODS_EFFECTIVE) == 1) {
         mods |= Qt::MetaModifier;
     }
+    if (xkb_state_mod_index_is_active(m_state, m_numModifier, XKB_STATE_MODS_EFFECTIVE) == 1) {
+        mods |= Qt::KeypadModifier;
+    }
     m_modifiers = mods;
 
     // update LEDs

xkb.h

@@ -58,6 +58,9 @@ public:
     void setConfig(KSharedConfigPtr config) {
         m_config = config;
     }
+    void setNumLockConfig(KSharedConfigPtr config) {
+        m_numLockConfig = config;
+    }
     void reconfigure();
 
     void installKeymap(int fd, uint32_t size);
@@ -130,6 +133,7 @@ private:
     xkb_mod_index_t m_controlModifier;
     xkb_mod_index_t m_altModifier;
     xkb_mod_index_t m_metaModifier;
+    xkb_mod_index_t m_numModifier;
     xkb_led_index_t m_numLock;
     xkb_led_index_t m_capsLock;
     xkb_led_index_t m_scrollLock;
@@ -144,6 +148,7 @@ private:
     } m_compose;
     LEDs m_leds;
     KSharedConfigPtr m_config;
+    KSharedConfigPtr m_numLockConfig;
 
     struct {
         xkb_mod_index_t depressed = 0;
@@ -151,6 +156,12 @@ private:
         xkb_mod_index_t locked = 0;
     } m_modifierState;
 
+    enum class Ownership {
+        Server,
+        Client
+    };
+    Ownership m_ownership = Ownership::Server;
+
     QPointer<KWayland::Server::SeatInterface> m_seat;
 };