threadSafeQueue.hpp

//******************************************************************************
//
// Copyright (c) 2019, Brandon To
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#ifndef _TOPIC_MONITOR_QUEUE_HPP_
#define _TOPIC_MONITOR_QUEUE_HPP_

#include <condition_variable>
#include <mutex>
#include <queue>

#include "common.hpp"

namespace topicMonitor
{

template <class T>
class ThreadSafeQueue
{
public:
    ThreadSafeQueue(void) {}
    ~ThreadSafeQueue(void) {}

    void push(T entry_p)
    {
        std::unique_lock<std::mutex> lock(mutex_m);
        queue_m.push(entry_p);
        lock.unlock();
        cond_m.notify_one();
    }

    T pop(void)
    {
        std::unique_lock<std::mutex> lock(mutex_m);

        while (queue_m.empty())
        {
            cond_m.wait(lock);
        }

        T entry_p = queue_m.front();
        queue_m.pop();
        return entry_p;
    }

private:
    std::queue<T>           queue_m;
    std::mutex              mutex_m;
    std::condition_variable cond_m;
};

} /* namespace topicMonitor */

#endif /* _TOPIC_MONITOR_QUEUE_HPP_ */