concurrent_queue.hpp

#pragma once
#ifndef _CONCURRENT_QUEUE_H
#define _CONCURRENT_QUEUE_H

#include <queue>
#include <boost/thread.hpp>

template<typename Data>
class concurrent_queue
{
private:
 std::queue<Data> the_queue;
 mutable boost::mutex the_mutex;
 boost::condition_variable the_condition_variable;
public:
 void push(Data const& data)
 {
 boost::lock_guard<boost::mutex> lock(the_mutex);
 the_queue.push(data);
 the_condition_variable.notify_one();
 }

 bool empty() const
 {
 boost::lock_guard<boost::mutex> lock(the_mutex);
 return the_queue.empty();
 }

 bool try_pop(Data& popped_value)
 {
 boost::unique_lock<boost::mutex> lock(the_mutex);
 if( the_queue.empty() )
 {
 return false;
 }
 
 popped_value = the_queue.front();
 the_queue.pop();
 return true;
 }

 void wait_and_pop(Data& popped_value)
 {
 boost::unique_lock<boost::mutex> lock(the_mutex);

 while( the_queue.empty() )
 {
 the_condition_variable.wait(lock);
 }
 
 popped_value = the_queue.front();
 the_queue.pop();
 }

};

#endif