Question

I’m wondering if this is the right approach to writing a thread-safe queue in C++?

template <class T>
class Queue
{
public:

Queue() {}

void Push(T& a)
{
    m_mutex.lock();
    m_q.push_back(a);
    m_mutex.unlock();
}

T& Pop()
{
    m_mutex.lock();
    T& temp = m_q.pop();
    m_mutex.unlock();
    return temp;
}

private:
    std::queue<t> m_q;
    boost::mutex m_mutex;
};

You get the idea… I’m just wondering if this is the best approach. Thanks!

EDIT:
Because of the questions I’m getting, I wanted to clarify that the mutex is a boost::mutex

Answer 1

Herb Sutter wrote an excellent article last year in Dr. Dobbs Journal, covering all of the major concerns for a thread-safe, lock-free, single-producer, single-consumer queue implementation. (Which made corrections over an implementation published the previous month.)

His followup article in the next issue tackled a more generic approach for a multi-user concurrent queue, along with a full discussion of potential pitfalls and performance issues.

There are a few more articles on similar concurrency topics.

Enjoy.