Highlander code

1 files changed, 68 insertions, 0 deletions

diff --git a/singleapplication.cpp b/singleapplication.cpp
new file mode 100644
index 00000000..fc668f97
--- /dev/null
+++ b/singleapplication.cpp
@@ -0,0 +1,68 @@
+#include <QLocalSocket>
+
+#include "singleapplication.h"
+
+SingleApplication::SingleApplication(int &argc, char *argv[], const QString uniqueKey) : QApplication(argc, argv), _uniqueKey(uniqueKey)
+{
+        sharedMemory.setKey(_uniqueKey);
+        if (sharedMemory.attach())
+                _isRunning = true;
+        else
+        {
+                _isRunning = false;
+                // create shared memory.
+                if (!sharedMemory.create(1))
+                {
+                        qDebug("Unable to create single instance.");
+                        return;
+                }
+                // create local server and listen to incomming messages from other instances.
+                localServer = new QLocalServer(this);
+                connect(localServer, SIGNAL(newConnection()), this, SLOT(receiveMessage()));
+                localServer->listen(_uniqueKey);
+        }
+}
+
+// public slots.
+
+void SingleApplication::receiveMessage()
+{
+        QLocalSocket *localSocket = localServer->nextPendingConnection();
+        if (!localSocket->waitForReadyRead(timeout))
+        {
+                qDebug() << localSocket->errorString().toLatin1();
+                return;
+        }
+        QByteArray byteArray = localSocket->readAll();
+        QString message = QString::fromUtf8(byteArray.constData());
+        emit messageAvailable(message);
+        localSocket->disconnectFromServer();
+}
+
+// public functions.
+
+bool SingleApplication::isRunning()
+{
+        return _isRunning;
+}
+
+bool SingleApplication::sendMessage(const QString &message)
+{
+        if (!_isRunning)
+                return false;
+        QLocalSocket localSocket(this);
+        localSocket.connectToServer(_uniqueKey, QIODevice::WriteOnly);
+        if (!localSocket.waitForConnected(timeout))
+        {
+                qDebug() << localSocket.errorString().toLatin1();
+                return false;
+        }
+        localSocket.write(message.toUtf8());
+        if (!localSocket.waitForBytesWritten(timeout))
+        {
+                qDebug() << localSocket.errorString().toLatin1();
+                return false;
+        }
+        localSocket.disconnectFromServer();
+        return true;
+}