/*
	Lan Wars.
	Copyright (c) 2009, Darragh Coy.
	All rights reserved.
	Original work(s), source code & author(s) details available at: http://www.darraghcoy.com

	Redistribution and use in source and binary forms, with or without modification, are permitted 
	provided that the following conditions are met:

		* 	Redistributions of source code must retain the above copyright notice, this list of 
			conditions and the following disclaimer.
		* 	Redistributions in binary form must reproduce the above copyright notice, this list of 
			conditions and the following disclaimer in the documentation.
		* 	Neither the name of the author nor the names of contributors may be used to endorse or 
			promote products derived from this software without specific prior written permission.
		* 	The use of any third party libraries, modules or data files provided with the source 
			form of the program must follow and respect the individual licensing terms of these 
			components. You do not have permission to modify or circumvent the licensing terms for 
			provided third party components unless the third party licenses specifically allow this. 
			If you do not agree to the terms of provided third party components then you do not have 
			permission to use them in your derived work(s).
		* 	The terms of this license do not apply to separate (but related) distributions if supplied 
			by the author(s), only to the contents of this source distribution, derived works, and the 
			binaries produced by either modified or unmodified versions of the source code. The terms 
			of this license do not also apply to any third party libraries or components provided with 
			the source distribution. Such third party elements are licensed under their own separate 
			agreements.

	THIS SOFTWARE IS PROVIDED BY DARRAGH COY ''AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, 
	BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
	ARE DISCLAIMED. IN NO EVENT SHALL DARRAGH COY BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
	EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 
	OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 
	OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
	IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#ifndef GAME_MUTEX_H
#define GAME_MUTEX_H

//=====================================================================================================================
//=====================================================================================================================

namespace Game
{
	//=================================================================================================================
	/// @brief		This class represents a mutex, which is a synchronisation object that can be only held by one 
	///				thread at a time.
	//=================================================================================================================

	class Mutex
	{
		public:
			
			//=========================================================================================================
			// Functions
			//=========================================================================================================
					    
				/// Creates the mutex
			    
				Mutex( bool initial_owner = false , bool exit_on_failure = true );

				/// Destroys the mutex

				~Mutex();

				/// Locks the mutex, accquires ownership of the mutex by this thread or waits till free

				void Lock();

				/// Frees the mutex, releases this threads hold on the mutex

				void Unlock();

				/// Tells if this mutex is held by a thread

				bool IsLocked();

				/// Tells if this mutex is not held by a thread

				inline bool IsUnlocked(){ return ! IsLocked(); }

				/// Tells if the mutex is valid: no attempt should be made to use an invalid mutex

				bool IsValid(){ return m_mutex_handle != 0; }
			
		private:
		
			//=========================================================================================================
			// Functions
			//=========================================================================================================
			
				/// Cannot be copied
				
				Mutex( const Mutex & other );
				
				/// Cannot be copied
				
				Mutex & operator = ( const Mutex & other );
		
			//=========================================================================================================
			// Variables
			//=========================================================================================================			
		
				/// Handle to the Win32 mutex

				HANDLE m_mutex_handle;

				#ifdef DEBUG

					/// Debug only variable which indicates the id of the current thread that holds the mutex

					DWORD m_owner_thread_id;

				#endif
	};
};

#endif 
