Create a dedicated X11EventFilter for recognizing first user interaction

Summary:
Workspace monitors the X11 events to detect when the user first
interacts with the system. This is only required on X11 for activating
the same client from previous session. So far this was spread over many
parts in the long event switch statement. To make this more contained a
dedicated event filter is introduced which also gets deleted again once
the first user interaction got recognized.

Test Plan: Compiles

Reviewers: #kwin, #plasma

Subscribers: plasma-devel, kwin

Tags: #kwin

Differential Revision: https://phabricator.kde.org/D7371

CMakeLists.txt

@@ -455,6 +455,7 @@ set(kwin_KDEINIT_SRCS
     popup_input_filter.cpp
     abstract_opengl_context_attribute_builder.cpp
     egl_context_attribute_builder.cpp
+    was_user_interaction_x11_filter.cpp
    )
 
 if(KWIN_BUILD_TABBOX)

events.cpp

@@ -265,7 +265,6 @@ bool Workspace::workspaceEvent(xcb_generic_event_t *e)
     switch (eventType) {
     case XCB_BUTTON_PRESS:
     case XCB_BUTTON_RELEASE: {
-        was_user_interaction = true;
         auto *mouseEvent = reinterpret_cast<xcb_button_press_event_t*>(e);
 #ifdef KWIN_BUILD_TABBOX
         if (TabBox::TabBox::self()->isGrabbed()) {
@@ -301,7 +300,6 @@ bool Workspace::workspaceEvent(xcb_generic_event_t *e)
         break;
     }
     case XCB_KEY_PRESS: {
-        was_user_interaction = true;
         int keyQt;
         xcb_key_press_event_t *event = reinterpret_cast<xcb_key_press_event_t*>(e);
         KKeyServer::xcbKeyPressEventToQt(event, &keyQt);
@@ -319,7 +317,6 @@ bool Workspace::workspaceEvent(xcb_generic_event_t *e)
         break;
     }
     case XCB_KEY_RELEASE:
-        was_user_interaction = true;
 #ifdef KWIN_BUILD_TABBOX
         if (TabBox::TabBox::self()->isGrabbed()) {
             TabBox::TabBox::self()->keyRelease(reinterpret_cast<xcb_key_release_event_t*>(e));
@@ -644,12 +641,10 @@ bool Client::windowEvent(xcb_generic_event_t *e)
         break;
     case XCB_KEY_PRESS:
         updateUserTime(reinterpret_cast<xcb_key_press_event_t*>(e)->time);
-        workspace()->setWasUserInteraction();
         break;
     case XCB_BUTTON_PRESS: {
         const auto *event = reinterpret_cast<xcb_button_press_event_t*>(e);
         updateUserTime(event->time);
-        workspace()->setWasUserInteraction();
         buttonPressEvent(event->event, event->detail, event->state,
                          event->event_x, event->event_y, event->root_x, event->root_y, event->time);
         break;
@@ -1068,7 +1063,6 @@ bool Client::buttonPressEvent(xcb_window_t w, int button, int state, int x, int
     if (w == wrapperId() || w == frameId() || w == inputId()) {
         // FRAME neco s tohohle by se melo zpracovat, nez to dostane dekorace
         updateUserTime(time);
-        workspace()->setWasUserInteraction();
         const bool bModKeyHeld = modKeyDown(state);
 
         if (isSplash()

was_user_interaction_x11_filter.cpp

@@ -0,0 +1,38 @@
+/********************************************************************
+ 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 "was_user_interaction_x11_filter.h"
+#include "workspace.h"
+#include <xcb/xcb.h>
+
+namespace KWin
+{
+WasUserInteractionX11Filter::WasUserInteractionX11Filter()
+    : X11EventFilter(QVector<int>{XCB_KEY_PRESS, XCB_KEY_RELEASE, XCB_BUTTON_PRESS, XCB_BUTTON_RELEASE})
+{
+}
+
+bool WasUserInteractionX11Filter::event(xcb_generic_event_t *event)
+{
+    Q_UNUSED(event);
+    workspace()->setWasUserInteraction();
+    return false;
+}
+
+}

was_user_interaction_x11_filter.h

@@ -0,0 +1,37 @@
+/********************************************************************
+ 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/>.
+*********************************************************************/
+#ifndef KWIN_WAS_USER_INTERACTION_X11_FILTER_H
+#define KWIN_WAS_USER_INTERACTION_X11_FILTER_H
+#include "x11eventfilter.h"
+
+namespace KWin
+{
+
+class WasUserInteractionX11Filter : public X11EventFilter
+{
+public:
+    explicit WasUserInteractionX11Filter();
+
+    bool event(xcb_generic_event_t *event) override;
+};
+
+}
+
+#endif

workspace.cpp

@@ -54,6 +54,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "useractions.h"
 #include "virtualdesktops.h"
 #include "shell_client.h"
+#include "was_user_interaction_x11_filter.h"
 #include "wayland_server.h"
 #include "xcbutils.h"
 #include "main.h"
@@ -214,6 +215,9 @@ Workspace::Workspace(const QString &sessionKey)
 
 void Workspace::init()
 {
+    if (kwinApp()->operationMode() == Application::OperationModeX11) {
+        m_wasUserInteractionFilter.reset(new WasUserInteractionX11Filter);
+    }
     updateXTime(); // Needed for proper initialization of user_time in Client ctor
     KSharedConfigPtr config = kwinApp()->config();
     kwinApp()->createScreens();
@@ -1786,5 +1790,19 @@ void Workspace::markXStackingOrderAsDirty()
     m_xStackingQueryTree.reset(new Xcb::Tree(rootWindow()));
 }
 
+void Workspace::setWasUserInteraction()
+{
+    if (was_user_interaction) {
+        return;
+    }
+    was_user_interaction = true;
+    // might be called from within the filter, so delay till we now the filter returned
+    QTimer::singleShot(0, this,
+        [this] {
+            m_wasUserInteractionFilter.reset();
+        }
+    );
+}
+
 } // namespace
 

workspace.h

@@ -571,6 +571,7 @@ private:
     GroupList groups;
 
     bool was_user_interaction;
+    QScopedPointer<X11EventFilter> m_wasUserInteractionFilter;
     bool session_saving;
     int session_active_client;
     int session_desktop;
@@ -691,11 +692,6 @@ inline const ToplevelList& Workspace::stackingOrder() const
     return stacking_order;
 }
 
-inline void Workspace::setWasUserInteraction()
-{
-    was_user_interaction = true;
-}
-
 inline bool Workspace::wasUserInteraction() const
 {
     return was_user_interaction;