[GTK] Handle global modifiers state in the UI process only

https://bugs.webkit.org/show_bug.cgi?id=258965

Reviewed by Michael Catanzaro.

The web process updates the global modifiers state on every key event
received and when the view gets focused.

* Source/WebCore/platform/PlatformKeyboardEvent.h:
* Source/WebCore/platform/gtk/GtkUtilities.cpp:
(WebCore::eventModifiersContainCapsLock):
* Source/WebCore/platform/gtk/GtkUtilities.h:
* Source/WebCore/platform/gtk/GtkVersioning.h:
(gtk_event_controller_get_current_event):
(gdk_event_get_display):
* Source/WebCore/platform/gtk/PlatformKeyboardEventGtk.cpp:
(WebCore::PlatformKeyboardEvent::currentStateOfModifierKeys):
(WebCore::PlatformKeyboardEvent::modifiersContainCapsLock): Deleted.
* Source/WebKit/Shared/gtk/WebEventFactory.cpp:
(WebKit::modifiersForEvent):
* Source/WebKit/UIProcess/API/gtk/WebKitWebViewBase.cpp:
(modifiersForSynthesizedEvent):
(webkitWebViewBaseTouchRelease):
(webkitWebViewBaseTouchDragUpdate):
(webkitWebViewBaseTouchDragEnd):
(toWebKitModifiers):
* Source/WebKit/UIProcess/WebPageProxy.cpp:
(WebKit::WebPageProxy::updateCurrentModifierState):
* Source/WebKit/UIProcess/WebPageProxy.h:
* Source/WebKit/UIProcess/gtk/WebPageProxyGtk.cpp:
(WebKit::WebPageProxy::currentStateOfModifierKeys):

Canonical link: https://commits.webkit.org/266095@main

Source/WebCore/platform/PlatformKeyboardEvent.h

@@ -135,7 +135,6 @@ namespace WebCore {
         static String keyIdentifierForGdkKeyCode(unsigned);
         static int windowsKeyCodeForGdkKeyCode(unsigned);
         static String singleCharacterString(unsigned);
-        static bool modifiersContainCapsLock(unsigned);
 #endif
 
 #if USE(LIBWPE)

Source/WebCore/platform/gtk/GtkUtilities.cpp

@@ -221,4 +221,16 @@ bool shouldUseOverlayScrollbars()
     return !!overlayScrolling;
 }
 
+bool eventModifiersContainCapsLock(GdkEvent* event)
+{
+#if USE(GTK4)
+    auto* device = gdk_event_get_source_device(event);
+    if (!device || gdk_device_get_source(device) != GDK_SOURCE_KEYBOARD)
+        device = gdk_seat_get_keyboard(gdk_display_get_default_seat(gdk_event_get_display(event)));
+    return gdk_device_get_caps_lock_state(device);
+#else
+    return gdk_keymap_get_caps_lock_state(gdk_keymap_get_for_display(gdk_event_get_display(event)));
+#endif
+}
+
 } // namespace WebCore

Source/WebCore/platform/gtk/GtkUtilities.h

@@ -59,4 +59,6 @@ void monitorWorkArea(GdkMonitor*, GdkRectangle*);
 
 bool shouldUseOverlayScrollbars();
 
+WEBCORE_EXPORT bool eventModifiersContainCapsLock(GdkEvent*);
+
 } // namespace WebCore

Source/WebCore/platform/gtk/GtkVersioning.h

@@ -276,6 +276,12 @@ gtk_scrolled_window_new()
     return gtk_scrolled_window_new(nullptr, nullptr);
 }
 
+static inline GdkEvent*
+gtk_event_controller_get_current_event(GtkEventController*)
+{
+    return gtk_get_current_event();
+}
+
 static inline GdkModifierType
 gtk_event_controller_get_current_event_state(GtkEventController*)
 {
@@ -295,4 +301,10 @@ static inline GtkIconTheme* gtk_icon_theme_get_for_display(GdkDisplay* display)
     return gtk_icon_theme_get_for_screen(gdk_display_get_default_screen(display));
 }
 
+static inline GdkDisplay*
+gdk_event_get_display(GdkEvent* event)
+{
+    return event->any.window ? gdk_window_get_display(event->any.window) : gdk_display_get_default();
+}
+
 #endif // USE(GTK4)

Source/WebCore/platform/gtk/PlatformKeyboardEventGtk.cpp

@@ -38,7 +38,6 @@
 #include <gdk/gdkkeysyms.h>
 #include <pal/text/TextEncoding.h>
 #include <wtf/HexNumber.h>
-#include <wtf/glib/GUniquePtr.h>
 
 namespace WebCore {
 
@@ -1350,58 +1349,10 @@ void PlatformKeyboardEvent::disambiguateKeyDownEvent(Type type, bool backwardCom
 
 OptionSet<PlatformEvent::Modifier> PlatformKeyboardEvent::currentStateOfModifierKeys()
 {
-    GdkModifierType state;
-#if USE(GTK4)
-    state = static_cast<GdkModifierType>(0); // FIXME: Implement.
-#else
-    gtk_get_current_event_state(&state);
-#endif
+    if (s_currentModifiers)
+        return *s_currentModifiers;
 
-    OptionSet<PlatformEvent::Modifier> modifiers;
-
-    if (state & GDK_SHIFT_MASK)
-        modifiers.add(PlatformEvent::Modifier::ShiftKey);
-    if (state & GDK_CONTROL_MASK)
-        modifiers.add(PlatformEvent::Modifier::ControlKey);
-    if (state & GDK_MOD1_MASK)
-        modifiers.add(PlatformEvent::Modifier::AltKey);
-    if (state & GDK_META_MASK)
-        modifiers.add(PlatformEvent::Modifier::MetaKey);
-
-#if USE(GTK4)
-    bool capsLockActive = gdk_device_get_caps_lock_state(gdk_seat_get_keyboard(gdk_display_get_default_seat(gdk_display_get_default())));
-#else
-    bool capsLockActive = gdk_keymap_get_caps_lock_state(gdk_keymap_get_for_display(gdk_display_get_default()));
-#endif
-    if (capsLockActive)
-        modifiers.add(PlatformEvent::Modifier::CapsLockKey);
-
-    return modifiers;
-}
-
-bool PlatformKeyboardEvent::modifiersContainCapsLock(unsigned modifier)
-{
-    if (!(modifier & GDK_LOCK_MASK))
-        return false;
-
-    // In X11 GDK_LOCK_MASK could be CapsLock or ShiftLock, depending on the modifier mapping of the X server.
-    // What GTK+ does in the X11 backend is checking if there is a key bound to GDK_KEY_Caps_Lock, so we do
-    // the same here. This will also return true in Wayland if there's a caps lock key, so it's not worth it
-    // checking the actual display here.
-    static bool lockMaskIsCapsLock = false;
-#if !USE(GTK4)
-    static bool initialized = false;
-    if (!initialized) {
-        GUniqueOutPtr<GdkKeymapKey> keys;
-        int entriesCount;
-#if USE(GTK4)
-        lockMaskIsCapsLock = gdk_display_map_keyval(gdk_display_get_default(), GDK_KEY_Caps_Lock, &keys.outPtr(), &entriesCount) && entriesCount;
-#else
-        lockMaskIsCapsLock = gdk_keymap_get_entries_for_keyval(gdk_keymap_get_for_display(gdk_display_get_default()), GDK_KEY_Caps_Lock, &keys.outPtr(), &entriesCount) && entriesCount;
-#endif
-    }
-#endif
-    return lockMaskIsCapsLock;
+    return { };
 }
 
 }

Source/WebKit/Shared/gtk/WebEventFactory.cpp

@@ -69,7 +69,7 @@ static inline OptionSet<WebEventModifier> modifiersForEvent(const GdkEvent* even
         modifiers.add(WebEventModifier::AltKey);
     if (state & GDK_META_MASK)
         modifiers.add(WebEventModifier::MetaKey);
-    if (PlatformKeyboardEvent::modifiersContainCapsLock(state))
+    if (state & GDK_LOCK_MASK && eventModifiersContainCapsLock(const_cast<GdkEvent*>(event)))
         modifiers.add(WebEventModifier::CapsLockKey);
 
     GdkEventType type = gdk_event_get_event_type(const_cast<GdkEvent*>(event));

Source/WebKit/UIProcess/API/gtk/WebKitWebViewBase.cpp

@@ -2139,6 +2139,24 @@ static void webkitWebViewBaseTouchPress(WebKitWebViewBase* webViewBase, int nPre
     webViewBase->priv->isLongPressed = false;
 }
 
+static unsigned modifiersForSynthesizedEvent(GdkEvent* event)
+{
+    if (!event)
+        return 0;
+
+    GdkModifierType state;
+    if (!gdk_event_get_state(event, &state))
+        return 0;
+
+    unsigned modifiers = state;
+    // For synthesized events we assume GDK_LOCK_MASK is always CapsLock
+    // so we remove the flag if present and caps lock state is disabled.
+    if (modifiers & GDK_LOCK_MASK && !eventModifiersContainCapsLock(event))
+        modifiers &= ~GDK_LOCK_MASK;
+
+    return modifiers;
+}
+
 static void webkitWebViewBaseTouchRelease(WebKitWebViewBase* webViewBase, int nPress, double x, double y, GtkGesture* gesture)
 {
     WebKitWebViewBasePrivate* priv = webViewBase->priv;
@@ -2157,7 +2175,7 @@ static void webkitWebViewBaseTouchRelease(WebKitWebViewBase* webViewBase, int nP
         buttons = GDK_BUTTON1_MASK;
     }
 
-    unsigned modifiers = gtk_event_controller_get_current_event_state(GTK_EVENT_CONTROLLER(gesture));
+    unsigned modifiers = modifiersForSynthesizedEvent(gtk_event_controller_get_current_event(GTK_EVENT_CONTROLLER(gesture)));
     webkitWebViewBaseSynthesizeMouseEvent(webViewBase, MouseEventType::Motion, 0, 0, x, y, modifiers, nPress, mousePointerEventType(), PlatformMouseEvent::IsTouch::Yes);
     webkitWebViewBaseSynthesizeMouseEvent(webViewBase, MouseEventType::Press, button, 0, x, y, modifiers, nPress, mousePointerEventType(), PlatformMouseEvent::IsTouch::Yes);
     webkitWebViewBaseSynthesizeMouseEvent(webViewBase, MouseEventType::Release, button, buttons, x, y, modifiers, nPress, mousePointerEventType(), PlatformMouseEvent::IsTouch::Yes);
@@ -2187,7 +2205,7 @@ static void webkitWebViewBaseTouchDragUpdate(WebKitWebViewBase* webViewBase, dou
     auto* sequence = gtk_gesture_single_get_current_sequence(GTK_GESTURE_SINGLE(gesture));
     auto* event = gtk_gesture_get_last_event(gesture, sequence);
 
-    unsigned modifiers = gtk_event_controller_get_current_event_state(GTK_EVENT_CONTROLLER(gesture));
+    unsigned modifiers = modifiersForSynthesizedEvent(gtk_event_controller_get_current_event(GTK_EVENT_CONTROLLER(gesture)));
     if (!priv->isBeingDragged) {
         if (!gtk_drag_check_threshold(GTK_WIDGET(webViewBase), 0, 0, static_cast<int>(offsetX), static_cast<int>(offsetY)))
             return;
@@ -2231,7 +2249,7 @@ static void webkitWebViewBaseTouchDragEnd(WebKitWebViewBase* webViewBase, gdoubl
     if (priv->isLongPressed) {
         double x, y;
         gtk_gesture_drag_get_start_point(GTK_GESTURE_DRAG(gesture), &x, &y);
-        unsigned modifiers = gtk_event_controller_get_current_event_state(GTK_EVENT_CONTROLLER(gesture));
+        unsigned modifiers = modifiersForSynthesizedEvent(gtk_event_controller_get_current_event(GTK_EVENT_CONTROLLER(gesture)));
         webkitWebViewBaseSynthesizeMouseEvent(webViewBase, MouseEventType::Release, GDK_BUTTON_PRIMARY, GDK_BUTTON1_MASK, x + offsetX, y + offsetY, modifiers, 0, mousePointerEventType(), PlatformMouseEvent::IsTouch::Yes);
     }
 }
@@ -3049,7 +3067,7 @@ static inline OptionSet<WebEventModifier> toWebKitModifiers(unsigned modifiers)
         webEventModifiers.add(WebEventModifier::AltKey);
     if (modifiers & GDK_META_MASK)
         webEventModifiers.add(WebEventModifier::MetaKey);
-    if (PlatformKeyboardEvent::modifiersContainCapsLock(modifiers))
+    if (modifiers & GDK_LOCK_MASK)
         webEventModifiers.add(WebEventModifier::CapsLockKey);
     return webEventModifiers;
 }

Source/WebKit/UIProcess/WebPageProxy.cpp

@@ -11756,8 +11756,12 @@ void WebPageProxy::getIsViewVisible(bool& result)
 
 void WebPageProxy::updateCurrentModifierState()
 {
+#if PLATFORM(COCOA) || PLATFORM(GTK)
 #if PLATFORM(COCOA)
     auto modifiers = PlatformKeyboardEvent::currentStateOfModifierKeys();
+#elif PLATFORM(GTK)
+    auto modifiers = currentStateOfModifierKeys();
+#endif
     send(Messages::WebPage::UpdateCurrentModifierState(modifiers));
 #endif
 }

Source/WebKit/UIProcess/WebPageProxy.h

@@ -169,6 +169,7 @@ enum class ModalContainerDecision : uint8_t;
 enum class MouseEventPolicy : uint8_t;
 enum class PermissionName : uint8_t;
 enum class PermissionState : uint8_t;
+enum class PlatformEventModifier : uint8_t;
 enum class PolicyAction : uint8_t;
 enum class ReasonForDismissingAlternativeText : uint8_t;
 enum class ReloadOption : uint8_t;
@@ -2523,6 +2524,7 @@ class WebPageProxy final : public API::ObjectImpl<API::Object::Type::Page>, publ
 
 #if PLATFORM(GTK)
     void showEmojiPicker(const WebCore::IntRect&, CompletionHandler<void(String)>&&);
+    OptionSet<WebCore::PlatformEventModifier> currentStateOfModifierKeys();
 #endif
 
     // Popup Menu.

Source/WebKit/UIProcess/gtk/WebPageProxyGtk.cpp

@@ -37,6 +37,7 @@
 #include "WebPasteboardProxy.h"
 #include "WebProcessProxy.h"
 #include <WebCore/PlatformDisplay.h>
+#include <WebCore/PlatformEvent.h>
 #include <wtf/NeverDestroyed.h>
 
 namespace WebKit {
@@ -117,4 +118,30 @@ void WebPageProxy::accentColorDidChange()
     send(Messages::WebPage::SetAccentColor(accentColor));
 }
 
+OptionSet<WebCore::PlatformEvent::Modifier> WebPageProxy::currentStateOfModifierKeys()
+{
+#if USE(GTK4)
+    auto* device = gdk_seat_get_keyboard(gdk_display_get_default_seat(gtk_widget_get_display(viewWidget())));
+    auto gdkModifiers = gdk_device_get_modifier_state(device);
+    bool capsLockActive = gdk_device_get_caps_lock_state(device);
+#else
+    auto* keymap = gdk_keymap_get_for_display(gtk_widget_get_display(viewWidget()));
+    auto gdkModifiers = gdk_keymap_get_modifier_state(keymap);
+    bool capsLockActive = gdk_keymap_get_caps_lock_state(keymap);
+#endif
+
+    OptionSet<WebCore::PlatformEvent::Modifier> modifiers;
+    if (gdkModifiers & GDK_SHIFT_MASK)
+        modifiers.add(WebCore::PlatformEvent::Modifier::ShiftKey);
+    if (gdkModifiers & GDK_CONTROL_MASK)
+        modifiers.add(WebCore::PlatformEvent::Modifier::ControlKey);
+    if (gdkModifiers & GDK_MOD1_MASK)
+        modifiers.add(WebCore::PlatformEvent::Modifier::AltKey);
+    if (gdkModifiers & GDK_META_MASK)
+        modifiers.add(WebCore::PlatformEvent::Modifier::MetaKey);
+    if (capsLockActive)
+        modifiers.add(WebCore::PlatformEvent::Modifier::CapsLockKey);
+    return modifiers;
+}
+
 } // namespace WebKit