【Linux系统编程】条件变量实现生产者消费者模型

条件变量实现生产者消费者模型

一个生产者一个消费者模型

#include <iostream>
#include <unistd.h>
#include <pthread.h>
#include <deque>

using namespace std;

deque<int> msg;

pthread_cond_t has_product = PTHREAD_COND_INITIALIZER;
pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;

void* consumer(void *p) {
    srand(time(0));
    for (;;) {
        pthread_mutex_lock(&lock);
        while (msg.size() == 0) {
            pthread_cond_wait(&has_product, &lock);
        }
        cout << "Consume:" << msg.front() << endl;
        msg.pop_front();
        pthread_mutex_unlock(&lock);
        sleep(rand() % 10);
    }
}

void* producer(void *p) {
    srand(time(0));
    for (;;) {
        int product = rand() % 10000;
        pthread_mutex_lock(&lock);
        msg.push_back(product);
        cout << "Produce:" << product << endl;
        pthread_mutex_unlock(&lock);
        pthread_cond_signal(&has_product);
        sleep(rand() % 5);
    }
}

int main(int argc, char *argv[]) {
    pthread_t pid;
    pthread_t cid;

    pthread_create(&pid, nullptr, producer, nullptr);
    pthread_create(&cid, nullptr, consumer, nullptr);

    pthread_join(pid, nullptr);
    pthread_join(cid, nullptr);
    return 0;
}