用BlockBoundQueue和c++11实现多线程生产者消费者问题

// file : blockBoundQueue.h
#ifndef YANG_BLOCKBOUNDQUEUE
#define YANG_BLOCKBOUNDQUEUE
#include <mutex>
#include <condition_variable>
#include <queue>
#include <cstdio>
namespace yang{
#define _FULL 4 //
template <typename _Tp>
class BlockBoundQueue
{
public:
    BlockBoundQueue(size_t bound = _FULL) :bound_(bound){}
    BlockBoundQueue(const BlockBoundQueue&) = delete;
    BlockBoundQueue& operator=(const BlockBoundQueue&) = delete;
    void push(const _Tp& value)
    {
        std::unique_lock<std::mutex> lck(mutex_);// 利用RAII技法,将mutex_托管给lck
        while (count_ + 1 == bound_)// 用while防止虚假唤醒 
        {
            printf("the queue is full , waiting for the consumer consuming !\n");
            notFull_.wait(lck); //等待队列非满条件发生
        }
        count_++;
        queue_.push(value);
        notEmpty_.notify_one();//通知队列非空,不能用all,读者自行思考为什么
    }
    _Tp get() 
    {
        std::unique_lock<std::mutex> lck(mutex_);
        while (queue_.empty())
        {
            printf("the queue is empty , waiting for the producer producing !\n");
            notEmpty_.wait(lck);//等待队列为非空
        }
        _Tp front(queue_.front());
        queue_.pop();
        count_--;
        notFull_.notify_one();//通知队列为非满,请注意不能用all
        return front;
    }
private:
    std::mutex mutex_;
    std::condition_variable notEmpty_;
    std::condition_variable notFull_;
    std::queue<_Tp> queue_;
    size_t count_{ 0 };
    size_t bound_;
};
}
#endif
//在visual studio 2013上编译运行通过

  

// file : main.cpp
#include <cstdio>
#include <cstdlib>
#include <thread>
#include "BlockBoundQueue.h"
yang::BlockBoundQueue<int> blockboundqueue_;// 全局的缓冲边界队列
const int total = 16; // 商品总数
void consumer(size_t id,size_t n); // 消费者
void producer(size_t id,size_t n); // 生产者
int main()
{
    std::thread consumer1(consumer,0, 5);
    std::thread consumer2(consumer,1, 5);
    std::thread consumer3(consumer,2, 6);
    std::thread producer1(producer,0, 8);
    std::thread producer2(producer,1, 8);
    consumer1.join();
    consumer2.join();
    consumer3.join();
    producer1.join();
    producer2.join();
    system("pause");
    return 0;
}
void consumer(size_t id,size_t n)
{
    for (auto i = 0; i < n; ++i)
    {
        std::this_thread::sleep_for(std::chrono::seconds(2));
        int item = blockboundqueue_.get();
        printf("the %d^th consumer thread has consumed the %d^th item\n", id,item);
    }
}

void producer(size_t id,size_t n)
{
    for (int i = 0; i < n; ++i)
    {
        blockboundqueue_.push(i);
        printf("the %d^th producer thread has produced the %d^th item\n",id, i);
    }
}

【转】https://blog.csdn.net/dhz625/article/details/72026666

posted on 2019-11-26 20:03  lydstory  阅读(238)  评论(0)    收藏  举报

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