C++实现简单的生产者-消费者队列详解

#ifndef PRODUCER_CONSUMER_QUEUE_H
#define PRODUCER_CONSUMER_QUEUE_H

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

template<typename T>
class ProducerConsumerQueue {
public:
    ProducerConsumerQueue(int size) : m_maxSize(size), m_curSize(0) {}

    void push(T& val) {
        std::unique_lock<std::mutex> lock(m_mutex);
        while (m_curSize >= m_maxSize) {
            m_notFull.wait(lock);
        }
        m_queue.push(val);
        ++m_curSize;
        m_notEmpty.notify_one();
    }

    T pop() {
        std::unique_lock<std::mutex> lock(m_mutex);
        while (m_curSize <= 0) {
            m_notEmpty.wait(lock);
        }
        T val = m_queue.front();
        m_queue.pop();
        --m_curSize;
        m_notFull.notify_one();
        return val;
    }

    int size() {
        std::unique_lock<std::mutex> lock(m_mutex);
        return m_curSize;
    }

private:
    std::queue<T> m_queue;
    int m_maxSize;
    int m_curSize;
    std::mutex m_mutex;
    std::condition_variable m_notEmpty;
    std::condition_variable m_notFull;
};

#endif //PRODUCER_CONSUMER_QUEUE_H

#include <iostream>
#include "ProducerConsumerQueue.h"
int main() {
    ProducerConsumerQueue<int> queue(2);
    // 生产者线程
    std::thread producer([&queue] {
        for (int i = 0; i < 10; ++i) {
            queue.push(i);
        }
        });
    // 消费者线程
    std::thread consumer([&queue] {
        for (int i = 0; i < 10; ++i) {
            int value = queue.pop();
            std::cout << "Consumed " << value << std::endl;
            std::cout << queue.size() << std::endl;
        }
        });
    producer.join();
    consumer.join();
}