[keyboard] Add support for setting the layout via locale1

setxkbmap only works on X11/XWayland, and even on XWayland does not
correctly change the Wayland keyboard layout.

The "modern" way to control the system keyboard layout is via the
locale1 DBus interface (or the localectl frontend). On compositors like
KWin, this will update the keyboard layout on the fly, which is what we
want.

Implement support for setting the layout/model configs using locale1.
This is enabled by default when Calamares runs under Wayland, and can be
controlled via a config setting.

Signed-off-by: Hector Martin <marcan@marcan.st>

src/modules/keyboard/CMakeLists.txt

@@ -3,6 +3,9 @@
 #   SPDX-FileCopyrightText: 2020 Adriaan de Groot <groot@kde.org>
 #   SPDX-License-Identifier: BSD-2-Clause
 #
+
+find_package(Qt5 ${QT_VERSION} CONFIG REQUIRED Core DBus)
+
 calamares_add_plugin(keyboard
     TYPE viewmodule
     EXPORT_MACRO PLUGINDLLEXPORT_PRO
@@ -19,6 +22,8 @@ calamares_add_plugin(keyboard
     RESOURCES
         keyboard.qrc
     SHARED_LIB
+    LINK_LIBRARIES
+        Qt5::DBus
 )
 
 calamares_add_test(keyboardtest SOURCES Tests.cpp SetKeyboardLayoutJob.cpp RESOURCES keyboard.qrc)

src/modules/keyboard/Config.cpp

@@ -23,9 +23,14 @@
 #include "utils/Variant.h"
 
 #include <QApplication>
+#include <QGuiApplication>
 #include <QProcess>
 #include <QTimer>
 
+#include <QtDBus/QDBusConnection>
+#include <QtDBus/QDBusInterface>
+#include <QtDBus/QDBusReply>
+
 /* Returns stringlist with suitable setxkbmap command-line arguments
  * to set the given @p model.
  */
@@ -163,7 +168,14 @@ Config::Config( QObject* parent )
              {
                  // Set Xorg keyboard model
                  m_selectedModel = m_keyboardModelsModel->key( index );
-                 QProcess::execute( "setxkbmap", xkbmap_model_args( m_selectedModel ) );
+                 if ( m_useLocale1 )
+                 {
+                     locale1Apply();
+                 }
+                 else
+                 {
+                     QProcess::execute( "setxkbmap", xkbmap_model_args( m_selectedModel ) );
+                 }
                  emit prettyStatusChanged();
              } );
 
@@ -201,12 +213,55 @@ Config::xkbChanged( int index )
         m_setxkbmapTimer.disconnect( this );
     }
 
-    connect( &m_setxkbmapTimer, &QTimer::timeout, this, &Config::xkbApply );
+    if ( m_useLocale1 )
+    {
+        connect( &m_setxkbmapTimer, &QTimer::timeout, this, &Config::locale1Apply );
+    }
+    else
+    {
+        connect( &m_setxkbmapTimer, &QTimer::timeout, this, &Config::xkbApply );
+    }
 
     m_setxkbmapTimer.start( QApplication::keyboardInputInterval() );
     emit prettyStatusChanged();
 }
 
+void
+Config::locale1Apply()
+{
+    m_additionalLayoutInfo = getAdditionalLayoutInfo( m_selectedLayout );
+
+    QString layout = m_selectedLayout;
+    QString variant = m_selectedVariant;
+    QString option;
+
+    if ( !m_additionalLayoutInfo.additionalLayout.isEmpty() )
+    {
+        layout = m_additionalLayoutInfo.additionalLayout + "," + layout;
+        variant = m_additionalLayoutInfo.additionalVariant + "," + layout;
+        option = m_additionalLayoutInfo.groupSwitcher;
+    }
+
+    QDBusInterface locale1( "org.freedesktop.locale1",
+                            "/org/freedesktop/locale1",
+                            "org.freedesktop.locale1",
+                            QDBusConnection::systemBus() );
+    if ( !locale1.isValid() )
+    {
+        cWarning() << "Interface" << locale1.interface() << "is not valid.";
+        return;
+    }
+
+    // Using convert=true, this also updates the VConsole config
+    {
+        QDBusReply< void > r = locale1.call( "SetX11Keyboard", layout, m_selectedModel, variant, option, true, false );
+        if ( !r.isValid() )
+        {
+            cWarning() << "Could not set keyboard config through org.freedesktop.locale1.X11Keyboard." << r.error();
+        }
+    }
+}
+
 void
 Config::xkbApply()
 {
@@ -561,6 +616,7 @@ void
 Config::setConfigurationMap( const QVariantMap& configurationMap )
 {
     using namespace CalamaresUtils;
+    bool isX11 = QGuiApplication::platformName() == "xcb";
 
     const auto xorgConfDefault = QStringLiteral( "00-keyboard.conf" );
     m_xOrgConfFileName = getString( configurationMap, "xOrgConfFileName", xorgConfDefault );
@@ -570,6 +626,7 @@ Config::setConfigurationMap( const QVariantMap& configurationMap )
     }
     m_convertedKeymapPath = getString( configurationMap, "convertedKeymapPath" );
     m_writeEtcDefaultKeyboard = getBool( configurationMap, "writeEtcDefaultKeyboard", true );
+    m_useLocale1 = getBool( configurationMap, "useLocale1", !isX11 );
 }
 
 void

src/modules/keyboard/Config.h

@@ -89,6 +89,7 @@ private:
      */
     void xkbChanged( int index );
     void xkbApply();
+    void locale1Apply();
 
     KeyboardModelsModel* m_keyboardModelsModel;
     KeyboardLayoutModel* m_keyboardLayoutsModel;
@@ -107,6 +108,7 @@ private:
     QString m_xOrgConfFileName;
     QString m_convertedKeymapPath;
     bool m_writeEtcDefaultKeyboard = true;
+    bool m_useLocale1;
 
     // The state determines whether we guess settings or preserve them:
     // - Initial -> Guessing

src/modules/keyboard/keyboard.conf

@@ -21,3 +21,9 @@ convertedKeymapPath: "/lib/kbd/keymaps/xkb"
 # found on Debian-related systems.
 # Defaults to true if nothing is set.
 #writeEtcDefaultKeyboard:   true
+
+# Use the Locale1 service instead of directly managing configuration files.
+# This is the modern mechanism for configuring the systemwide keyboard layout,
+# and works on Wayland compositors to set the current layout.
+# Defaults to false on X11 and true otherwise.
+#useLocale1: true

src/modules/keyboardq/CMakeLists.txt

@@ -8,6 +8,8 @@ if(NOT WITH_QML)
     return()
 endif()
 
+find_package(Qt5 ${QT_VERSION} CONFIG REQUIRED Core DBus)
+
 set(_keyboard ${CMAKE_CURRENT_SOURCE_DIR}/../keyboard)
 
 include_directories(${_keyboard})
@@ -24,4 +26,6 @@ calamares_add_plugin(keyboardq
     RESOURCES
         keyboardq.qrc
     SHARED_LIB
+    LINK_LIBRARIES
+        Qt5::DBus
 )