/**************************************************************
 * 
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * 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
 * 
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 * 
 *************************************************************/


#ifndef _VOS_MUTEX_HXX_
#define _VOS_MUTEX_HXX_

#	include <vos/types.hxx>
#	include <vos/object.hxx>
#	include <osl/mutex.h>

namespace vos
{     


/** IMutex interface

	@author  Bernd Hofner
	@version 1.0
*/

class IMutex
{
public:

	/// Blocks if Mutex is already in use
	virtual void SAL_CALL acquire()= 0;			

	// Tries to get the mutex without blocking.
	virtual sal_Bool SAL_CALL tryToAcquire()= 0;

	/// releases the mutex.
	virtual void SAL_CALL release()= 0;

protected:
	IMutex() { }
	virtual ~IMutex() { }
    
};

// ----------------------------------------------------------

/** OMutex

	@author  Bernd Hofner
	@version 1.0
*/

class OMutex : public OObject, public IMutex
{
	VOS_DECLARE_CLASSINFO(VOS_NAMESPACE(OMutex, vos));

public:
	static IMutex& SAL_CALL getGlobalMutex();

	/// Creates mutex
	OMutex();	
	/// Implicitly destroys mutex	
    virtual ~OMutex();	
	
	/// Blocks if Mutex is already in use
	virtual void SAL_CALL acquire();	

	/** Tries to get the mutex without blocking.
		@return True if mutex could be obtained, otherwise False
	*/
	virtual sal_Bool SAL_CALL tryToAcquire();

	/// releases the mutex.
	virtual void SAL_CALL release();

protected:
	oslMutex	m_Impl;

private:
	// disable copy/assignment
	OMutex(const OMutex&);	
	OMutex& SAL_CALL operator= (const OMutex&);	
};

// *********************************************************************************

/** OGuard

	@author  Bernd Hofner
	@version 1.0
*/

class OGuard
{
	OGuard( const OGuard& );
	const OGuard& operator = ( const OGuard& );
public:
	/** Acquires mutex
	    @param pMutex pointer to mutex which is to be acquired	*/
	OGuard(IMutex* pMutex)
		: m_rMutex( *pMutex )
	{	// only for compatible reasons
		m_rMutex.acquire();
	}
	OGuard(IMutex & rMutex)
		: m_rMutex( rMutex )
	{
		m_rMutex.acquire();
	}

	/** Releases mutex. */
	virtual ~OGuard()
	{
		m_rMutex.release();
	}

protected:
	IMutex& m_rMutex;
};

/** A guard that can release the mutex with the clear method.

	@author  Bernd Hofner
	@version 1.0
*/
class OClearableGuard
{
	OClearableGuard( const OClearableGuard& );
	const OClearableGuard& operator = ( const OClearableGuard& );
public:
	/** Acquires mutex
	    @param pMutex pointer to mutex which is to be acquired	*/
	OClearableGuard(IMutex & rMutex)
		: m_pMutex( &rMutex )
	{
		m_pMutex->acquire();
	}

	/** Releases mutex. */
	virtual ~OClearableGuard()
	{
		if( m_pMutex )
			m_pMutex->release();
	}

	/** Releases mutex. */
	void SAL_CALL clear()
	{
		if( m_pMutex )
		{
			m_pMutex->release();
			m_pMutex = NULL;
		}
	}
protected:
	IMutex* m_pMutex;
};

}     


#endif  //_VOS_MUTEX_HXX_