1 files changed, 88 insertions, 0 deletions
diff --git a/src/singleinstance.h b/src/singleinstance.h
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+++ b/src/singleinstance.h
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+/*
+Copyright (C) 2012 Sebastian Herbord. All rights reserved.
+
+This file is part of Mod Organizer.
+
+Mod Organizer 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 3 of the License, or
+(at your option) any later version.
+
+Mod Organizer 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 Mod Organizer.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef SINGLEINSTANCE_H
+#define SINGLEINSTANCE_H
+
+#include <QObject>
+#include <QSharedMemory>
+#include <QLocalServer>
+
+
+/**
+ * used to ensure only a single instance of Mod Organizer is started and to
+ * allow secondary instances to send messages to the primary (visible) one. This way,
+ * secondary instances can start a download in the primary one
+ **/
+class SingleInstance : public QObject
+{
+
+  Q_OBJECT
+
+public:
+
+  /**
+   * @brief constructor
+   *
+   * @param forcePrimary if true, this will be treated as the primary instance even
+   *                     if another instance is running. This is used after an update since
+   *                     the other instance is assumed to be in the process of quitting
+   * @param parent parent object
+   * @todo the forcePrimary parameter makes no sense. The second instance after an update
+   *       needs to delete the files from before the update so the first instance needs to quit
+   *       first anyway
+   **/
+  explicit SingleInstance(bool forcePrimary, QObject *parent = 0);
+
+  /**
+   * @return true if this is the primary instance (the one that gets to display a UI)
+   **/
+  bool primaryInstance() const { return m_PrimaryInstance; }
+
+  /**
+   * send a message to the primary instance. This can be used to transmit download urls
+   *
+   * @param message message to send
+   **/
+  void sendMessage(const QString &message);
+
+signals:
+
+  /**
+   * @brief emitted when a secondary instance has sent a message (to us)
+   *
+   * @param message the message we received
+   **/
+  void messageSent(const QString &message);
+
+public slots:
+
+private slots:
+
+  void receiveMessage();
+
+private:
+
+  bool m_PrimaryInstance;
+  QSharedMemory m_SharedMem;
+  QLocalServer m_Server;
+
+};
+
+#endif // SINGLEINSTANCE_H