/*
 * (c) Copyright Ascensio System SIA 2010-2014
 *
 * This program is a free software product. You can redistribute it and/or 
 * modify it under the terms of the GNU Affero General Public License (AGPL) 
 * version 3 as published by the Free Software Foundation. In accordance with 
 * Section 7(a) of the GNU AGPL its Section 15 shall be amended to the effect 
 * that Ascensio System SIA expressly excludes the warranty of non-infringement
 * of any third-party rights.
 *
 * This program is distributed WITHOUT ANY WARRANTY; without even the implied 
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR  PURPOSE. For 
 * details, see the GNU AGPL at: http://www.gnu.org/licenses/agpl-3.0.html
 *
 * You can contact Ascensio System SIA at Lubanas st. 125a-25, Riga, Latvia,
 * EU, LV-1021.
 *
 * The  interactive user interfaces in modified source and object code versions
 * of the Program must display Appropriate Legal Notices, as required under 
 * Section 5 of the GNU AGPL version 3.
 *
 * Pursuant to Section 7(b) of the License you must retain the original Product
 * logo when distributing the program. Pursuant to Section 7(e) we decline to
 * grant you any rights under trademark law for use of our trademarks.
 *
 * All the Product's GUI elements, including illustrations and icon sets, as
 * well as technical writing content are licensed under the terms of the
 * Creative Commons Attribution-ShareAlike 4.0 International. See the License
 * terms at http://creativecommons.org/licenses/by-sa/4.0/legalcode
 *
 */
 #pragma once

namespace MemoryMapping
{
	class CMappingFile
	{
	public:
		CMappingFile()
			: m_hMapping(NULL)
			, m_pView(NULL)
			, m_hFile(NULL)
		{
		}
		~CMappingFile()
		{
			Close();
			
		}
		
		BOOL Open(const CString& strPath)
		{
			Close();
			if (OpenExistingFile(strPath))
				return TRUE;
			return FALSE;
		}

		void Close()
		{
			if (m_pView)
			{
				UnmapViewOfFile(m_pView);
				m_pView = 0;
			}

			if (m_hMapping)
			{
				CloseHandle(m_hMapping);
				m_hMapping = 0;
			}
			if (m_hFile)
			{
				CloseHandle(m_hFile);
				m_hFile = NULL;
			}
		}
		BOOL Valid()
		{
			if (m_pView)
				return TRUE;

			return FALSE;
		}
		BYTE* GetData()
		{
			return (BYTE*)m_pView;
		}
		long GetSize() const
		{
			return m_dwDataSize;
		}
	private:
		HANDLE m_hMapping;
		HANDLE m_hFile;
		LPVOID m_pView;
		DWORD m_dwDataSize;
		BOOL OpenExistingFile(const CString& strPath)
		{
			
			m_hFile= CreateFile(strPath, GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0);

			
			if (INVALID_HANDLE_VALUE == m_hFile)
			{
				DWORD dwErr = GetLastError();
				return FALSE;
			}

			
			DWORD dwFileSizeHigh = 0;
			m_dwDataSize = 0;

			
			m_dwDataSize = GetFileSize(m_hFile, &dwFileSizeHigh);

			
			m_hMapping = CreateFileMapping(m_hFile, NULL, PAGE_READONLY, dwFileSizeHigh, m_dwDataSize, NULL);

			
			if (!m_hMapping)
			{
				Close();
				return FALSE;
			}

			
			m_pView = MapViewOfFile(m_hMapping, FILE_MAP_READ, 0, 0, 0);

			
			if (!m_pView)
			{
				DWORD dwErr = GetLastError();
				Close();
				return FALSE;
			}				
			
			return TRUE;
		}
	};
};