firebird/examples/udr/UdrCppExample.h

/*
 *  The contents of this file are subject to the Initial
 *  Developer's Public License Version 1.0 (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.ibphoenix.com/main.nfs?a=ibphoenix&page=ibp_idpl.
 *
 *  Software distributed under the License is distributed AS IS,
 *  WITHOUT WARRANTY OF ANY KIND, either express or implied.
 *  See the License for the specific language governing rights
 *  and limitations under the License.
 *
 *  The Original Code was created by Adriano dos Santos Fernandes
 *  for the Firebird Open Source RDBMS project.
 *
 *  Copyright (c) 2015 Adriano dos Santos Fernandes <[email protected]>
 *  and all contributors signed below.
 *
 *  All Rights Reserved.
 *  Contributor(s): ______________________________________.
 */

#ifndef UDR_CPP_EXAMPLE_H
#define UDR_CPP_EXAMPLE_H

#define FB_UDR_STATUS_TYPE ::Firebird::ThrowStatusWrapper

#include "ibase.h"
#include "firebird/UdrCppEngine.h"
#include <assert.h>
#include <stdio.h>


namespace
{
	template <typename T>
	class AutoReleaseClear
	{
	public:
		static void clear(T* ptr)
		{
			if (ptr)
				ptr->release();
		}
	};

	template <typename T>
	class AutoDisposeClear
	{
	public:
		static void clear(T* ptr)
		{
			if (ptr)
				ptr->dispose();
		}
	};

	template <typename T>
	class AutoDeleteClear
	{
	public:
		static void clear(T* ptr)
		{
			delete ptr;
		}
	};

	template <typename T>
	class AutoArrayDeleteClear
	{
	public:
		static void clear(T* ptr)
		{
			delete [] ptr;
		}
	};

	template <typename T, typename Clear>
	class AutoImpl
	{
	public:
		AutoImpl<T, Clear>(T* aPtr = NULL)
			: ptr(aPtr)
		{
		}

		~AutoImpl()
		{
			Clear::clear(ptr);
		}

		AutoImpl<T, Clear>& operator =(T* aPtr)
		{
			Clear::clear(ptr);
			ptr = aPtr;
			return *this;
		}

		operator T*()
		{
			return ptr;
		}

		operator const T*() const
		{
			return ptr;
		}

		bool operator !() const
		{
			return !ptr;
		}

		bool hasData() const
		{
			return ptr != NULL;
		}

		T* operator ->()
		{
			return ptr;
		}

		T* release()
		{
			T* tmp = ptr;
			ptr = NULL;
			return tmp;
		}

		void reset(T* aPtr = NULL)
		{
			if (aPtr != ptr)
			{
				Clear::clear(ptr);
				ptr = aPtr;
			}
		}

	private:
		// not implemented
		AutoImpl<T, Clear>(AutoImpl<T, Clear>&);
		void operator =(AutoImpl<T, Clear>&);

	private:
		T* ptr;
	};

	template <typename T> class AutoDispose : public AutoImpl<T, AutoDisposeClear<T> >
	{
	public:
		AutoDispose(T* ptr = NULL)
			: AutoImpl<T, AutoDisposeClear<T> >(ptr)
		{
		}
	};

	template <typename T> class AutoRelease : public AutoImpl<T, AutoReleaseClear<T> >
	{
	public:
		AutoRelease(T* ptr = NULL)
			: AutoImpl<T, AutoReleaseClear<T> >(ptr)
		{
		}
	};

	template <typename T> class AutoDelete : public AutoImpl<T, AutoDeleteClear<T> >
	{
	public:
		AutoDelete(T* ptr = NULL)
			: AutoImpl<T, AutoDeleteClear<T> >(ptr)
		{
		}
	};

	template <typename T> class AutoArrayDelete : public AutoImpl<T, AutoArrayDeleteClear<T> >
	{
	public:
		AutoArrayDelete(T* ptr = NULL)
			: AutoImpl<T, AutoArrayDeleteClear<T> >(ptr)
		{
		}
	};
}

#endif	// UDR_CPP_EXAMPLE_H