Wayland: Avoid delaying GUI start

Waits on activating clipboard in Wayland only when needed.

Author: hluk

CMakePresets.json

@@ -9,6 +9,7 @@
             "cacheVariables": {
                 "WITH_TESTS": "TRUE",
                 "PEDANTIC": "TRUE",
+                "CMAKE_BUILD_TYPE": "Debug",
                 "CMAKE_C_COMPILER_LAUNCHER": "ccache",
                 "CMAKE_CXX_COMPILER_LAUNCHER": "ccache"
             }

src/platform/x11/systemclipboard/waylandclipboard.cpp

@@ -595,25 +595,12 @@ WaylandClipboard::WaylandClipboard(QObject *parent)
     });
 
     m_manager->instantiate();
+    m_deviceRequestedTimer.start();
 }
 
 WaylandClipboard *WaylandClipboard::createInstance()
 {
-    qInfo() << "Using Wayland clipboard access";
-    auto clipboard = new WaylandClipboard(qApp);
-
-    QElapsedTimer timer;
-    timer.start();
-    while ( !clipboard->isActive() && timer.elapsed() < 5000 ) {
-        QCoreApplication::processEvents();
-    }
-    if ( timer.elapsed() > 100 ) {
-        qWarning() << "Activating Wayland clipboard took" << timer.elapsed() << "ms";
-    }
-    if ( !clipboard->isActive() ) {
-        qCritical() << "Failed to activate Wayland clipboard";
-    }
-    return clipboard;
+    return new WaylandClipboard(qApp);
 }
 
 void WaylandClipboard::setMimeData(QMimeData *mime, QClipboard::Mode mode)
@@ -664,6 +651,30 @@ const QMimeData *WaylandClipboard::mimeData(QClipboard::Mode mode) const
     return nullptr;
 }
 
+DataControlDevice *WaylandClipboard::device() const
+{
+    if (m_device)
+        return m_device.get();
+
+    if (m_deviceRequestedTimer.elapsed() > 5000)
+        return nullptr;
+
+    while (!m_device && m_deviceRequestedTimer.elapsed() < 5000) {
+        QCoreApplication::processEvents();
+    }
+
+    if (m_device) {
+        if (m_deviceRequestedTimer.elapsed() > 200) {
+            qWarning() << "Activating Wayland clipboard took"
+                << m_deviceRequestedTimer.elapsed() << "ms";
+        }
+        return m_device.get();
+    }
+
+    qCritical() << "Failed to activate Wayland clipboard";
+    return nullptr;
+}
+
 bool WaylandClipboard::isSelectionSupported() const
 {
     return m_device && zwlr_data_control_device_v1_get_version(m_device->object())

src/platform/x11/systemclipboard/waylandclipboard.h

@@ -6,6 +6,7 @@
 
 #pragma once
 #include <QClipboard>
+#include <QElapsedTimer>
 #include <QObject>
 #include <memory>
 
@@ -25,7 +26,7 @@ class WaylandClipboard final : public QObject
     void setMimeData(QMimeData *mime, QClipboard::Mode mode);
     void clear(QClipboard::Mode mode);
     const QMimeData *mimeData(QClipboard::Mode mode) const;
-    bool isActive() const { return m_device != nullptr; }
+    DataControlDevice *device() const;
     bool isSelectionSupported() const;
 
 signals:
@@ -37,4 +38,5 @@ class WaylandClipboard final : public QObject
 
     std::unique_ptr<DataControlDeviceManager> m_manager;
     std::unique_ptr<DataControlDevice> m_device;
+    QElapsedTimer m_deviceRequestedTimer;
 };