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72 lines
1.3 KiB
C++
72 lines
1.3 KiB
C++
//
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// SingletonHolder.h
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//
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// $Id: //poco/1.4/Foundation/include/Poco/SingletonHolder.h#1 $
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//
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// Library: Foundation
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// Package: Core
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// Module: SingletonHolder
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//
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// Definition of the SingletonHolder template.
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//
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// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
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// and Contributors.
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//
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// SPDX-License-Identifier: BSL-1.0
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//
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#ifndef Foundation_SingletonHolder_INCLUDED
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#define Foundation_SingletonHolder_INCLUDED
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#include "Poco/Foundation.h"
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#include "Poco/Mutex.h"
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namespace Poco {
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template <class S>
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class SingletonHolder
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/// This is a helper template class for managing
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/// singleton objects allocated on the heap.
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/// The class ensures proper deletion (including
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/// calling of the destructor) of singleton objects
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/// when the application that created them terminates.
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{
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public:
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SingletonHolder():
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_pS(0)
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/// Creates the SingletonHolder.
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{
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}
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~SingletonHolder()
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/// Destroys the SingletonHolder and the singleton
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/// object that it holds.
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{
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delete _pS;
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}
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S* get()
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/// Returns a pointer to the singleton object
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/// hold by the SingletonHolder. The first call
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/// to get will create the singleton.
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{
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FastMutex::ScopedLock lock(_m);
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if (!_pS) _pS = new S;
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return _pS;
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}
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private:
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S* _pS;
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FastMutex _m;
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};
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} // namespace Poco
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#endif // Foundation_SingletonHolder_INCLUDED
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