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diff --git a/src/utility/singleton.hpp b/src/utility/singleton.hpp
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+//
+// VMime library (http://vmime.sourceforge.net)
+// Copyright (C) 2002-2004 Vincent Richard <[email protected]>
+//
+// This program 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 2 of
+// the License, or (at your option) any later version.
+//
+// This program 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 this program; if not, write to the Free Software
+// Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+//
+
+#ifndef VMIME_UTILITY_SINGLETON_HPP_INCLUDED
+#define VMIME_UTILITY_SINGLETON_HPP_INCLUDED
+
+
+#include <list>
+
+
+namespace vmime {
+namespace utility {
+
+
+// Singleton abstract base class.
+
+class abstractSingleton
+{
+	friend class singletonManager;
+
+protected:
+
+	abstractSingleton() { }
+	virtual ~abstractSingleton() { }
+};
+
+
+// Singleton manager
+// (for automatic clean-up of all instanciated singletons).
+
+class singletonManager
+{
+public:
+
+	static singletonManager* getInstance();
+
+	void manage(abstractSingleton* s);
+
+private:
+
+	singletonManager();
+	~singletonManager();
+
+	std::list <abstractSingleton*> m_list;
+};
+
+
+// A singleton template.
+
+template <class TYPE>
+class singleton : public abstractSingleton
+{
+protected:
+
+	singleton() { }
+	~singleton() { }
+
+public:
+
+	static TYPE* getInstance()
+	{
+		static TYPE* inst = NULL;
+
+		if (!inst)
+			singletonManager::getInstance()->manage(inst = new TYPE());
+
+		return (inst);
+	}
+};
+
+
+} // utility
+} // vmime
+
+
+#endif // VMIME_UTILITY_SINGLETON_HPP_INCLUDED