Core: Improve communication single-instance

src/Gui/Application.cpp

@@ -2001,10 +2001,9 @@ bool onlySingleInstance(GUISingleApplication& mainApp)
                 fn = QDir::cleanPath(fn);
             }
 
-            QByteArray msg = fn.toUtf8();
-            msg.prepend("OpenFile:");
-            if (!mainApp.sendMessage(msg)) {
-                qWarning("Failed to send message to server");
+            fn.prepend(QLatin1String("OpenFile:"));
+            if (!mainApp.sendMessage(fn)) {
+                qWarning("Failed to send OpenFile message to server");
                 break;
             }
         }

src/Gui/GuiApplication.cpp

@@ -28,7 +28,7 @@
 # include <QAbstractSpinBox>
 # include <QByteArray>
 # include <QComboBox>
-# include <QDataStream>
+# include <QTextStream>
 # include <QFileInfo>
 # include <QFileOpenEvent>
 # include <QSessionManager>
@@ -218,7 +218,7 @@ public:
     QTimer *timer;
     QLocalServer *server{nullptr};
     QString serverName;
-    QList<QByteArray> messages;
+    QList<QString> messages;
     bool running{false};
 };
 
@@ -237,15 +237,16 @@ bool GUISingleApplication::isRunning() const
     return d_ptr->running;
 }
 
-bool GUISingleApplication::sendMessage(const QByteArray &message, int timeout)
+bool GUISingleApplication::sendMessage(const QString &message, int timeout)
 {
     QLocalSocket socket;
     bool connected = false;
     for(int i = 0; i < 2; i++) {
         socket.connectToServer(d_ptr->serverName);
         connected = socket.waitForConnected(timeout/2);
-        if (connected || i > 0)
+        if (connected || i > 0) {
             break;
+        }
         int ms = 250;
 #if defined(Q_OS_WIN)
         Sleep(DWORD(ms));
@@ -253,41 +254,56 @@ bool GUISingleApplication::sendMessage(const QByteArray &message, int timeout)
         usleep(ms*1000);
 #endif
     }
-    if (!connected)
+    if (!connected) {
         return false;
+    }
 
-    QDataStream ds(&socket);
-    ds << message;
-    socket.waitForBytesWritten(timeout);
-    return true;
+    QTextStream ts(&socket);
+#if QT_VERSION <= QT_VERSION_CHECK(6, 0, 0)
+    ts.setCodec("UTF-8");
+#else
+    ts.setEncoding(QStringConverter::Utf8);
+#endif
+    ts << message << Qt::endl;
+
+    return socket.waitForBytesWritten(timeout);
+}
+
+void GUISingleApplication::readFromSocket()
+{
+    auto socket = qobject_cast<QLocalSocket*>(sender());
+    if (socket) {
+        QTextStream in(socket);
+#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
+        in.setCodec("UTF-8");
+#else
+        in.setEncoding(QStringConverter::Utf8);
+#endif
+        while (socket->canReadLine()) {
+            d_ptr->timer->stop();
+            QString message = in.readLine();
+            Base::Console().Log("Received message: %s\n", message.toStdString());
+            d_ptr->messages.push_back(message);
+            d_ptr->timer->start(1000);
+        }
+    }
 }
 
 void GUISingleApplication::receiveConnection()
 {
     QLocalSocket *socket = d_ptr->server->nextPendingConnection();
-    if (!socket)
+    if (!socket) {
         return;
+    }
 
     connect(socket, &QLocalSocket::disconnected,
             socket, &QLocalSocket::deleteLater);
-    if (socket->waitForReadyRead()) {
-        QDataStream in(socket);
-        if (!in.atEnd()) {
-            d_ptr->timer->stop();
-            QByteArray message;
-            in >> message;
-            Base::Console().Log("Received message: %s\n", message.constData());
-            d_ptr->messages.push_back(message);
-            d_ptr->timer->start(1000);
-        }
-    }
-
-    socket->disconnectFromServer();
+    connect(socket, &QLocalSocket::readyRead, this, &GUISingleApplication::readFromSocket);
 }
 
 void GUISingleApplication::processMessages()
 {
-    QList<QByteArray> msg = d_ptr->messages;
+    QList<QString> msg = d_ptr->messages;
     d_ptr->messages.clear();
     Q_EMIT messageReceived(msg);
 }

src/Gui/GuiApplication.h

@@ -69,14 +69,15 @@ public:
     ~GUISingleApplication() override;
 
     bool isRunning() const;
-    bool sendMessage(const QByteArray &message, int timeout = 5000);
+    bool sendMessage(const QString &message, int timeout = 5000);
 
 private Q_SLOTS:
     void receiveConnection();
     void processMessages();
+    void readFromSocket();
 
 Q_SIGNALS:
-    void messageReceived(const QList<QByteArray> &);
+    void messageReceived(const QList<QString> &);
 
 private:
     class Private;

src/Gui/MainWindow.cpp

@@ -1556,16 +1556,16 @@ void MainWindow::hideEvent(QHideEvent* e)
     QMainWindow::hideEvent(e);
 }
 
-void MainWindow::processMessages(const QList<QByteArray> & msg)
+void MainWindow::processMessages(const QList<QString> & msg)
 {
     // handle all the messages to open files
     try {
         WaitCursor wc;
         std::list<std::string> files;
-        QByteArray action("OpenFile:");
+        QString action = QString::fromStdString("OpenFile:");
         for (const auto & it : msg) {
             if (it.startsWith(action))
-                files.emplace_back(it.mid(action.size()).constData());
+                files.emplace_back(it.mid(action.size()).toStdString());
         }
         files = App::Application::processFiles(files);
         for (const auto & file : files) {

src/Gui/MainWindow.h

@@ -350,7 +350,7 @@ private Q_SLOTS:
     /**
      * \internal
      */
-    void processMessages(const QList<QByteArray> &);
+    void processMessages(const QList<QString> &);
     /**
      * \internal
      */

src/Gui/StartupProcess.cpp

@@ -247,8 +247,8 @@ void StartupPostProcess::setWindowTitle()
 void StartupPostProcess::setProcessMessages()
 {
     if (!loadFromPythonModule) {
-        QObject::connect(qtApp, SIGNAL(messageReceived(const QList<QByteArray> &)),
-                         mainWindow, SLOT(processMessages(const QList<QByteArray> &)));
+        QObject::connect(qtApp, SIGNAL(messageReceived(const QList<QString> &)),
+                         mainWindow, SLOT(processMessages(const QList<QString> &)));
     }
 }