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 * 
 * Licensed to the Apache Software Foundation (ASF) under one
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 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
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#ifndef _SYNCOBJECTS_HXX_
#define _SYNCOBJECTS_HXX_

//------------------------------------------------------------------------
// includes
//------------------------------------------------------------------------

#include <windows.h>

//------------------------------------------------------------------------
// a simple helper template for automatic locking/unlocking 
//------------------------------------------------------------------------

template< class LOCK >
class CLockGuard
{
public:
	CLockGuard( LOCK* aLock ) : 
		m_pLock( aLock )
	{
		m_pLock->Lock( );
	}

	~CLockGuard( )
	{
		m_pLock->Unlock( );
	}

private:
	LOCK* m_pLock;
};

//------------------------------------------------------------------------
// a interface base class for different locking sub classes
//------------------------------------------------------------------------

class CSyncObject
{
public:
	virtual ~CSyncObject( ) = 0;

	virtual int Lock( )     = 0;
	virtual int Unlock( )   = 0;
};

//------------------------------------------------------------------------
// if no synchronization is necessary this class will be used 
// declaring the functions as inline safes runtime overhead
//------------------------------------------------------------------------

class CNullLock
{
public:
	inline virtual ~CNullLock ( ) {};
	inline virtual int Lock( )    {};
	inline virtual int Unlock()   {};
};

//------------------------------------------------------------------------
// a minimal wrapper for a win32 critical section
//------------------------------------------------------------------------

class CCriticalSection : public CSyncObject
{
public:
	CCriticalSection( );
	virtual ~CCriticalSection( );

	// both functions return always 0
	// because the win32 critsec functions
	// don't return any return code
	virtual int Lock( );
	virtual int Unlock( );

private:
	CRITICAL_SECTION m_critSec;
};


typedef CLockGuard< CSyncObject > SyncObjLockGuard_t;

#endif