reworked Queue, added TODO, corrected documentation, prepared execution of regular tasks in MainLoop

2015-10-31 16:22:53 +01:00
parent bd1c991c77
commit 5e9094a19b
1 changed files with 0 additions and 202 deletions
@@ -1,202 +0,0 @@
 /*
 * Copyright (C) Roland Jax 2012-2014 <ebusd@liwest.at>,
 * John Baier 2014-2015 <ebusd@ebusd.eu>
 *
 * This file is part of ebusd.
 *
 * ebusd is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * ebusd is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with ebusd. If not, see http://www.gnu.org/licenses/.
 */
 #ifndef LIBUTILS_WQUEUE_H_
 #define LIBUTILS_WQUEUE_H_
 #include <list>
 #include <pthread.h>
 /** \file wqueue.h */
 using namespace std;
 /**
 * @brief queue class template for all kinds data types with exclusiv lock.
 */
 template <typename T>
 class WQueue
 {
 public:
 	/**
 	 * @brief constructs a new instance.
 	 */
 	WQueue()
 	{
 		pthread_mutex_init(&m_mutex, NULL);
 		pthread_cond_init(&m_cond, NULL);
 	}
 	/**
 	 * @brief destructor.
 	 */
 	~WQueue()
 	{
 		pthread_mutex_destroy(&m_mutex);
 		pthread_cond_destroy(&m_cond);
 	}
 private:
 	/**
 	 * @brief Hidden copy constructor.
 	 * @param src the object to copy from.
 	 */
 	WQueue(const WQueue& src);
 public:
 	/**
 	 * @brief add a new item to the end of queue.
 	 * @param item to add.
 	 */
 	void add(T item)
 	{
 		pthread_mutex_lock(&m_mutex);
 		m_queue.push_back(item);
 		pthread_cond_broadcast(&m_cond);
 		pthread_mutex_unlock(&m_mutex);
 	}
 	/**
 	 * @brief remove the first item from queue.
 	 * @param wait true to wait for an item to be added to the queue, false to return NULL if no item is available.
 	 * @return the item, or NULL if no item is available and wait was false.
 	 */
 	T remove(bool wait=true)
 	{
 		pthread_mutex_lock(&m_mutex);
 		T item;
 		if (wait) {
 			while (m_queue.size() == 0)
 				pthread_cond_wait(&m_cond, &m_mutex);
 			item = m_queue.front();
 			m_queue.pop_front();
 		}
 		else if (m_queue.size() > 0) {
 			item = m_queue.front();
 			m_queue.pop_front();
 		}
 		else
 			item = NULL;
 		pthread_mutex_unlock(&m_mutex);
 		return item;
 	}
 	/**
 	 * @brief Remove the specified item from the queue.
 	 * @param item the item to remove.
 	 * @return whether the item was removed.
 	 */
 	bool remove(T item)
 	{
 		pthread_mutex_lock(&m_mutex);
 		size_t oldSize = m_queue.size();
 		if (oldSize > 0)
 			m_queue.remove(item);
 		size_t newSize = m_queue.size();
 		pthread_mutex_unlock(&m_mutex);
 		return newSize != oldSize;
 	}
 	/**
 	 * @brief Wait for the specified item to appear in the queue and remove it from the queue.
 	 * @param item the item to wait for and remove.
 	 * @return whether the item was removed.
 	 */
 	bool waitRemove(T item)
 	{
 		pthread_mutex_lock(&m_mutex);
 		do {
 			size_t oldSize = m_queue.size();
 			if (oldSize > 0) {
 				m_queue.remove(item);
 				if (m_queue.size() != oldSize)
 					break;
 			}
 			pthread_cond_wait(&m_cond, &m_mutex);
 		} while (true);
 		pthread_mutex_unlock(&m_mutex);
 		return true;
 	}
 	/**
 	 * @brief return the first item from the queue without remove.
 	 * @param wait whether to wait for an entry if the queue is empty.
 	 * @return the item, or NULL if no item is available and wait was false.
 	 */
 	T next(bool wait=true)
 	{
 		pthread_mutex_lock(&m_mutex);
 		T item;
 		if (wait) {
 			while (m_queue.size() == 0)
 				pthread_cond_wait(&m_cond, &m_mutex);
 			item = m_queue.front();
 		}
 		else if (m_queue.size() > 0)
 			item = m_queue.front();
 		else
 			item = NULL;
 		pthread_mutex_unlock(&m_mutex);
 		return item;
 	}
 	/**
 	 * @brief the number of entries inside queue.
 	 * @return the size.
 	 */
 	size_t size()
 	{
 		pthread_mutex_lock(&m_mutex);
 		size_t size = m_queue.size();
 		pthread_mutex_unlock(&m_mutex);
 		return size;
 	}
 private:
 	/** the queue itself */
 	list<T> m_queue;
 	/** mutex variable for exclusive lock */
 	pthread_mutex_t m_mutex;
 	/** condition variable for exclusive lock */
 	pthread_cond_t m_cond;
 };
 #endif // LIBUTILS_WQUEUE_H_