/*
 Copyright (c) 2008 TrueCrypt Foundation. All rights reserved.

 Governed by the TrueCrypt License 2.5 the full text of which is contained
 in the file License.txt included in TrueCrypt binary and source code
 distribution packages.
*/

#ifndef TC_HEADER_Platform_SharedVal
#define TC_HEADER_Platform_SharedVal

#include "PlatformBase.h"
#include "Mutex.h"

namespace TrueCrypt
{
	template <class T>
	class SharedVal
	{
	public:
		SharedVal () { }
		explicit SharedVal (T value) : Value (value) { }
		virtual ~SharedVal () { }

		operator T ()
		{
			return Get ();
		}

		T Decrement ()
		{
			ValMutex.Lock();
			T r = --Value;
			ValMutex.Unlock();
			return r;
		}

		T Get ()
		{
			ValMutex.Lock();
			T r = Value;
			ValMutex.Unlock();
			return r;
		}

		T Increment ()
		{
			ValMutex.Lock();
			T r = ++Value;
			ValMutex.Unlock();
			return r;
		}

		void Set (T value)
		{
			ValMutex.Lock();
			Value = value;
			ValMutex.Unlock();
		}

	protected:
		volatile T Value;
		Mutex ValMutex;

	private:
		SharedVal (const SharedVal &);
		SharedVal &operator= (const SharedVal &);
	};
}

#endif // TC_HEADER_Platform_SharedVal