EpServerEngine - A lightweight Template Server-Client Framework using C++ and Windows Winsock

/*! 
@file epThreadSafeQueue.h
@author Woong Gyu La a.k.a Chris. <juhgiyo@gmail.com>
		<http://github.com/juhgiyo/eplibrary>
@date July 07, 2010
@brief ThreadSafeQueue Interface
@version 2.0

@section LICENSE

The MIT License (MIT)

Copyright (c) 2008-2013 Woong Gyu La <juhgiyo@gmail.com>

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.

@section DESCRIPTION

An Interface for Thread Safe Queue.

*/
#ifndef __EP_THREAD_SAFE_QUEUE_H__
#define __EP_THREAD_SAFE_QUEUE_H__
#include "epLib.h"
#include <vector>
#include "epCriticalSectionEx.h"
#include "epMutex.h"
#include "epNoLock.h"
#include "epException.h"

namespace epl
{

	/*! 
	@class ThreadSafeQueue epThreadSafeQueue.h
	@brief A class for Thread Safe Queue.
	*/
	template <typename DataType>
	class ThreadSafeQueue
	{
	public:

		/*!
		Default Constructor

		Initializes the queue
		@param[in] lockPolicyType The lock policy
		*/
		ThreadSafeQueue(LockPolicy lockPolicyType=EP_LOCK_POLICY);

		/*!
		Default Copy Constructor

		Initializes the queue
		@param[in] b the second object
		*/
		ThreadSafeQueue(const ThreadSafeQueue& b);

		/*!
		Default Destructor

		Destroy the queue
		*/
		virtual ~ThreadSafeQueue();

		/*!
		Assignment Operator Overloading

		the ThreadSafeQueue set as given ThreadSafeQueue b
		@param[in] b right side of ThreadSafeQueue
		@return this object
		*/
		ThreadSafeQueue & operator=(const ThreadSafeQueue&b);

		/*!
		Check if the queue is empty.
		@returns Returns true if the queue is empty, otherwise false.
		*/
		bool IsEmpty() const;

		/*!
		Check if the given obj exists in the queue.
		@returns Returns true if exists, otherwise false.
		*/
		bool IsExist(DataType const &data) const;

		/*!
		Return the size of the queue.
		@return the size of the queue.
		*/
		size_t Size() const;

		/*!
		Return the first item within the queue.
		@return the first element of the queue.
		*/
		DataType &Front();

		/*!
		Return the last item within the queue.
		@return the last element of the queue.
		*/
		DataType &Back();

		/*!
		Insert the new item into the queue.
		@param[in] data The inserting data.
		*/
		virtual void Push(DataType const &data);

		/*!
		Erase the given item from the queue.
		@param[in] data The data to erase.
		*/
		bool Erase(DataType const &data);

		/*!
		Remove the first item from the queue.
		*/
		virtual void Pop();

		/*!
		Clear the queue.
		*/
		void Clear();

		std::vector<DataType> GetQueue() const;

	protected:
		/// Actual queue structure
		std::vector<DataType> m_queue;

		/// lock
		BaseLock *m_queueLock;

		/// Lock Policy
		LockPolicy m_lockPolicy;
	};


	template <typename DataType>
	ThreadSafeQueue<DataType>::ThreadSafeQueue(LockPolicy lockPolicyType)
	{
		m_lockPolicy=lockPolicyType;
		switch(lockPolicyType)
		{
		case LOCK_POLICY_CRITICALSECTION:
			m_queueLock=EP_NEW CriticalSectionEx();
			break;
		case LOCK_POLICY_MUTEX:
			m_queueLock=EP_NEW Mutex();
			break;
		case LOCK_POLICY_NONE:
			m_queueLock=EP_NEW NoLock();
			break;
		default:
			m_queueLock=NULL;
			break;
		}
	}

	template <typename DataType>
	ThreadSafeQueue<DataType>::ThreadSafeQueue(const ThreadSafeQueue& b)
	{
		m_queue=b.GetQueue();
		m_lockPolicy=b.m_lockPolicy;
		switch(m_lockPolicy)
		{
		case LOCK_POLICY_CRITICALSECTION:
			m_queueLock=EP_NEW CriticalSectionEx();
			break;
		case LOCK_POLICY_MUTEX:
			m_queueLock=EP_NEW Mutex();
			break;
		case LOCK_POLICY_NONE:
			m_queueLock=EP_NEW NoLock();
			break;
		default:
			m_queueLock=NULL;
			break;
		}
	}

	template <typename DataType>
	ThreadSafeQueue<DataType>::~ThreadSafeQueue()
	{
		m_queueLock->Lock();
		m_queue.clear();
		m_queueLock->Unlock();
		if(m_queueLock)
			EP_DELETE m_queueLock;
	}

	template <typename DataType>
	std::vector<DataType> ThreadSafeQueue<DataType>::GetQueue() const
	{
		LockObj lock(m_queueLock);
		return m_queue;
	}

	template <typename DataType>
	bool ThreadSafeQueue<DataType>::IsEmpty() const
	{
		LockObj lock(m_queueLock);
		return m_queue.empty();
	}
	
	template <typename DataType>
	bool ThreadSafeQueue<DataType>::IsExist(DataType const &data) const
	{
		LockObj lock(m_queueLock);
		if(m_queue.empty())
			return false;

		std::vector<DataType>::const_iterator iter;
		for(iter=m_queue.begin();iter!=m_queue.end();iter++)
		{
			if((*iter)==data)
				return true;
		}
		return false;
		
	}

	template <typename DataType>
	void ThreadSafeQueue<DataType>::Clear()
	{
		LockObj lock(m_queueLock);
		m_queue.clear();

	}

	template <typename DataType>
	size_t ThreadSafeQueue<DataType>::Size() const
	{
		LockObj lock(m_queueLock);
		return m_queue.size();
	}

	template <typename DataType>
	DataType &ThreadSafeQueue<DataType>::Front()
	{
		LockObj lock(m_queueLock);
		if(m_queue.empty())
		{
			EP_ASSERT_EXPR(0,_T("Empty Queue"));
		}
		return m_queue.front();
	}

	template <typename DataType>
	DataType &ThreadSafeQueue<DataType>::Back()
	{
		LockObj lock(m_queueLock);
		if(m_queue.empty())
		{
			EP_ASSERT_EXPR(0,_T("Empty Queue"));
		}
		return m_queue.back();
	}

	template <typename DataType>
	void ThreadSafeQueue<DataType>::Push(DataType const & data)
	{
		LockObj lock(m_queueLock);
		m_queue.push_back(data);
	}

	template <typename DataType>
	bool ThreadSafeQueue<DataType>::Erase(DataType const &data)
	{
		LockObj lock(m_queueLock);
		std::vector<DataType>::iterator iter;
		for(iter=m_queue.begin();iter!=m_queue.end();iter++)
		{
			if(*iter==data)
			{
				m_queue.erase(iter);
				return true;
			}
		}
		return false;
	}

	template <typename DataType>
	void ThreadSafeQueue<DataType>::Pop()
	{
		LockObj lock(m_queueLock);
		if(m_queue.empty())
		{
			EP_ASSERT_EXPR(0,_T("Empty Queue"));
		}
		m_queue.erase(m_queue.begin());
	}

	template <typename DataType>
	ThreadSafeQueue<DataType> & ThreadSafeQueue<DataType>::operator=(const ThreadSafeQueue& b)
	{
		if(this != &b)
		{
			if(m_queueLock)
			{
				EP_DELETE m_queueLock;
				m_queueLock=NULL;
			}
			m_lockPolicy=b.m_lockPolicy;
			switch(m_lockPolicy)
			{
			case LOCK_POLICY_CRITICALSECTION:
				m_queueLock=EP_NEW CriticalSectionEx();
				break;
			case LOCK_POLICY_MUTEX:
				m_queueLock=EP_NEW Mutex();
				break;
			case LOCK_POLICY_NONE:
				m_queueLock=EP_NEW NoLock();
				break;
			default:
				m_queueLock=NULL;
				break;
			}
			m_queue=b.GetQueue();
		}
		return *this;
	}
}
#endif //__EP_THREAD_SAFE_QUEUE_H__