demo源码 阻塞队列部分

queue.h //主要是对queue加了几把pv锁，对push和pop分别做了阻塞和非阻塞的封装，主要内容见注释，不复杂，此处不赘述。

#ifndef _QUEUE_H_
#define _QUEUE_H_
#include <queue>

namespace Queue
{
template<typename TYPE> class Queue
{
		private:
		typedef std::queue<TYPE> queue_t;

		queue_t m_queue;
		pthread_mutex_t  m_queuemutex;//互斥锁

		pthread_cond_t m_queuefill;
		bool m_waitqueuefill;//等待队列有数据可pop的条件变量

		pthread_cond_t  m_queuefree;
		bool m_waitqueuefree;//等待队列有空位可push的条件变量

		const size_t m_queuelen;//队列长度
		
	public:
		Queue(size_t queuelen): m_waitqueuefill(false), m_queuelen(queuelen){	};
		~Queue(){};

		// 返回队列大小
		size_t size()
		{
			return (size_t)m_queue.size();
		};

		//清空队列
		int clear()
		{
			pthread_mutex_lock(&m_queuemutex);
			while(!m_queue.empty());
				m_queue.pop();
			pthread_mutex_unlock(&m_queuemutex);
			return 0;
		};

		// 非阻塞方式pop队列中数据
		int pop_nonblock(TYPE &out)
		{
			pthread_mutex_lock(&m_queuemutex);
			if(m_queue.size() == 0)//队列空
			{
				pthread_mutex_unlock(&m_queuemutex);
				return -1;
			}
				

			out = m_queue.front();
			m_queue.pop();

			if(m_waitqueuefree){
				pthread_cond_signal(&m_queuefree);//通知阻塞push
				m_waitqueuefree = false;
			}
			pthread_mutex_unlock(&m_queuemutex);
			return 0;
		};

		// 阻塞式pop队列中数据
		int pop(TYPE &out)
		{
			pthread_mutex_lock(&m_queuemutex);
			while(m_queue.size() == 0){
				m_waitqueuefill = true;
				pthread_cond_wait(&m_queuefill, &m_queuemutex);// 队列空，令线程阻塞等待直至有数据
			}



			out = m_queue.front();
			m_queue.pop();



			if(m_waitqueuefree){
				pthread_cond_signal(&m_queuefree);//通知阻塞push
				m_waitqueuefree = false;
			}
			pthread_mutex_unlock(&m_queuemutex);
			return 0;
		};

		// 非阻塞式push数据进入队列
		int push_nonblock(TYPE & in)
		{
			pthread_mutex_lock(&m_queuemutex);
			if(m_queue.size() == m_queuelen)//队列满
			{
				pthread_mutex_unlock(&m_queuemutex);
				return -1;
			}


			m_queue.push(in);



			if(m_waitqueuefill){
				pthread_cond_signal(&m_queuefill);//通知阻塞pop
				m_waitqueuefill = false;
			}
			pthread_mutex_unlock(&m_queuemutex);
			return 0;
		};

		//阻塞式push数据进入队列
		int push(TYPE & in)
		{
			pthread_mutex_lock(&m_queuemutex);

			while(m_queue.size() == m_queuelen){
				m_waitqueuefree = true;
				pthread_cond_wait(&m_queuefree, &m_queuemutex);// 队列满，令线程阻塞等待直至可push数据
			}



			m_queue.push(in);



			if(m_waitqueuefill){
				pthread_cond_signal(&m_queuefill);//通知阻塞pop
				m_waitqueuefill = false;
			}
			pthread_mutex_unlock(&m_queuemutex);
			return 0;
		};
};
}
#endif