C语言调用库函数实现生产者消费者问题

  1 #include<stdio.h>

  2 #include<stdlib.h>

  3 #include<semaphore.h>

  4 #include<pthread.h>

  5 #include<unistd.h>

  6 

  7 #define NumOf_Producer 5  //the max num of producer

  8 #define NumOf_Consumer 10  //the max num of consumer

  9 #define Maxnum 10  //  the max num of product

 10 sem_t Empty_sem; //the goal of whether the num of product is null

 11 sem_t Full_sem;  //the goal of whether the num of product is equal to Maxnum

 12 

 13 pthread_mutex_t Mutex;  //the goal of whether someone use the buff

 14 

 15 int Producer_id = 0;

 16 int Consumer_id = 0;

 17 int NowNumOfProduce = 0;

 18 void *Producer(void *arg)    //the thread of producer

 19 {

 20     int id = Producer_id++;

 21     while(1)

 22     {

 23         sleep(0.1);

 24         sem_wait(&Full_sem);   //when it comes to zero ,it means that the num of product is equal to Maxnum

 25         pthread_mutex_lock(&Mutex);  //lock the buff

 26         NowNumOfProduce++;

 27         printf("Producerthread %d product one,the num is:%d \n",id%NumOf_Producer,NowNumOfProduce);

 28         pthread_mutex_unlock(&Mutex);

 29         sem_post(&Empty_sem);   //when it comes to ten ,it means there are ten products can be used by consumer

 30     }

 31 

 32     return ((void *)0);

 33 }

 34 

 35 void *Consumer(void *arg)

 36 {

 37     int id = Consumer_id++;

 38     while(1)

 39     {

 40         sleep(0.2);

 41         sem_wait(&Empty_sem);

 42         pthread_mutex_lock(&Mutex);

 43         NowNumOfProduce--;

 44         printf("Consumerthread %d use product one,the num is:%d \n",id%NumOf_Consumer,NowNumOfProduce);

 45         pthread_mutex_unlock(&Mutex);

 46         sem_post(&Full_sem);

 47     }

 48     return ((void *)0);

 49 }

 50 

 51 int main()

 52 {

 53     pthread_t Con[NumOf_Consumer];

 54     pthread_t Pro[NumOf_Producer];

 55 

 56     int temp1 = sem_init(&Empty_sem,0,0);

 57     int temp2 = sem_init(&Full_sem,0,Maxnum);

 58     if(temp1&&temp2!=0)

 59     {

 60         printf("sem init failed \n");

 61         exit(1);

 62     }

 63 

 64     int temp3 = pthread_mutex_init(&Mutex,NULL);

 65 

 66     if(temp3!=0)

 67     {

 68         printf("Mutex init failed \n");

 69         exit(1);

 70     }

 71 

 72     for(int i=0 ;i<NumOf_Producer;i++)

 73     {

 74         int temp4 = pthread_create(&Pro[i],NULL,Producer,(void *)&i);

 75         if(temp4!=0)

 76         {

 77             printf("thread create failed !\n");

 78             exit(1);

 79         }

 80     }

 81 

 82     for(int i=0;i<NumOf_Consumer;i++)

 83     {

 84         int temp5 = pthread_create(&Con[i],NULL,Consumer,(void *)&i);

 85         if(temp5!=0)

 86         {

 87             printf("thread create failed !\n");

 88         }

 89         exit(1);

 90     }

 91     //destroy the thread

 92     for(int i=0;i<NumOf_Consumer;i++)

 93     {

 94            pthread_join(Con[i],NULL);

 95     }

 96 

 97     for(int i=0;i<NumOf_Producer;i++)

 98     {

 99         pthread_join(Pro[i],NULL);

100     }

101 

102     return 0;

103 }

说明：unisted.h是用来调用sleep，pthread.h是linux系统下线程编程的库，semaphore.h是使用信号灯的函数库，至于那些初始化方法，wait方法，post等可以去查查的。如果在编译程序时候出现类似sem_t未定义等问题，需要设置一下link链接，找到linux系统下安装的lib库中的libpthread.so导入进去就好了。