linux环形buff模拟多线程信号量操作

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

#include <semaphore.h>
#include <pthread.h>
#define _SIZE_ 128

int buf[_SIZE_];
sem_t blanks;
sem_t datas;

//生产者
void *producter(void *val)
{
    int beg = 0;
    while(1)
    {
        sem_wait(&blanks);
        int data = rand()%1024;
        buf[beg] = data;

        printf("%s done... data = %d\n",__func__,data);
        sem_post(&datas);
        beg = (beg+1)%_SIZE_;
        sleep(3);
    }
    return NULL;
}

//消费者
void *consumer(void *val)
{
    int start = 0;
    while(1)
    {
        sem_wait(&datas);
        int data = buf[start];

        printf("%s dene... data = %d\n", __func__,data);
        sem_post(&blanks);
        start = (start+1)%_SIZE_;
        sleep(5);
    }
    return NULL;
}

int main(int argc, char const *argv[])
{
    sem_init(&blanks,0,_SIZE_);
    sem_init(&datas,0,0);

    pthread_t id1,id2;
    pthread_create(&id1,NULL,producter,NULL);
    pthread_create(&id2,NULL,consumer,NULL);

    pthread_join(id1,NULL);
    pthread_join(id2,NULL);

    sem_destroy(&blanks);
    sem_destroy(&datas);
    return 0;
}