C++:采用信号量实现生产者与消费者模式

// 采用信号量与缓冲队列实现生产者与消费者模式
#include 
#include 
#include 
#include "pthread.h"

#include 
#include 
#include 
#include 
#include 
#include 

class SEM_MODEL
{
private:
    bool runnnig_;
    std::thread pro_thread_;  // 生产者进程
    std::thread cons_thread_; // 消费者进程
    std::mutex mutex_;
    sem_t semP;             // 生产者信号量
    sem_t semC;             // 消费者信号
    std::queue buffer; // 缓冲队列

public:
    SEM_MODEL();
    SEM_MODEL(int num1, int num2);
    ~SEM_MODEL();

public:
    void start();
    void stop();
    static SEM_MODEL &instance()
    {
        static SEM_MODEL s;
        return s;
    }

private:
    void product(); // 进行生产
    void consume(); // 进行消费
};

SEM_MODEL::SEM_MODEL()
{
    runnnig_ = false;
    sem_init(&semP, 0, 5);
    sem_init(&semC, 0, 0);
}

SEM_MODEL::SEM_MODEL(int num1, int num2)
{
    runnnig_ = false;
    sem_init(&semP, 0, num1);
    sem_init(&semC, 0, num2);
}

SEM_MODEL::~SEM_MODEL()
{
    runnnig_ = false;
}
void SEM_MODEL::start()
{
    runnnig_ = true;
    pro_thread_ = std::thread(&SEM_MODEL::product, this);
    cons_thread_ = std::thread(&SEM_MODEL::consume, this);
}

void SEM_MODEL::stop()
{
    runnnig_ = false;
    if (pro_thread_.joinable())
    {
        pro_thread_.join();
    }
    if (cons_thread_.joinable())
    {
        cons_thread_.join();
    }
}

void SEM_MODEL::product()
{
    while (runnnig_)
    {
        sem_wait(&semP);
        mutex_.lock();
        int elem = (rand() + 100) % 101;
        this->buffer.push(elem);
        std::cout << "正在写入元素：" << elem << std::endl;
        mutex_.unlock();
        sem_post(&semC);
        usleep(20);
    }
}

void SEM_MODEL::consume()
{
    while (runnnig_)
    {
        sem_wait(&semC);
        mutex_.lock();
        int elem = buffer.front();
        buffer.pop();
        std::cout << "正在弹出元素:" << elem << std::endl;
        mutex_.unlock();
        sem_post(&semP);
        usleep(10);
    }
}

int main()
{
    SEM_MODEL sem_model(5, 0);
    sem_model.start();
    // 开始启动
    while (true)
    { 
    }
    sem_model.stop();
    return 0;
}