【Linux】中的生产者与消费者的关系

问题描述：一组生产者向一组消费者提供消息，它们共享一个有界缓冲池，生产者向其中投放消息，消费者从中取得消息。假定这些生产者和消费者互相等效，只要缓冲池未满，生产者可将消息送入缓冲池；只要缓冲池未空，消费者可从缓冲池取走一个消息。 

功能要求：根据进程同步机制，编写一个解决上述问题的程序，可显示缓冲池状态、放数据、取数据等过程。 

首先使用链表的方法来编写代码：

#include<stdio.h>#include<pthread.h>#include<stdlib.h>pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;pthread_cond_t cond = PTHREAD_COND_INITIALIZER;typedef struct Node//定义一个Node的结构体{int val;struct Node* next;}Node_t,*Node_p,**Node_pp;Node_p head = NULL;Node_p allocNode(int Val){Node_p ret = (Node_p)malloc(sizeof(Node_t));ret->val=Val;ret->next=NULL;return ret;}void freeNode(Node_p del)//清空链表{free(del);}int initList(Node_pp _head)//初始化链表{*_head = allocNode(0);//对头结点初始化if(*_head == NULL)//如果头结点为空，直接返回{return 0;}return -1;//如果头结点不为空，返回-1}int Empty(Node_p _head){return (_head->next=NULL?0:-1);}int PopNode(Node_p _head,int *Val){if(Empty(_head) == 0){return -1;}Node_p del = _head->next;*Val = del->val;freeNode(del);del = NULL;return 0;}void PrintList(Node_p _head){Node_p tmp = _head->next;while(tmp){printf("%d",tmp->val);tmp=tmp->next;}printf("\n");}void Destroy(Node_pp _head){while(Empty(*_head)<0){int tmp;PopNode(*_head,&tmp);}freeNode(*_head);*_head = NULL;}void *consumer(void *arg){while(1){pthread_mutex_lock(&lock);int _val = rand()%1024;PushNode(head,_val);printf("consumer push done:%d \n",_val);sleep(1);pthread_mutex_unlock(&lock);pthread_cond_signal(&cond);}return NULL;}void *producter(void *arg){while(1){pthread_mutex_lock(&lock);if(Empty(head)==0){printf("producter check\n");pthread_cond_wait(&cond,&lock);}else{int _val;PopBNode(head,&_val);printf("producter pop done : %d\n",_val);}sleep(1);pthread_muyex_unlock(&lock);}}int main(){initList(&head);pthread_t c,p;pthread_creat(&c,NULL,consumer,NULL);pthread_creat(&p,NULL,producter,NULL);pthread_join(c,NULL);pthread_join(p,NULL);DestroyList(&head);pthread_mutex_destroy(&lock);pthread_cond_destroy(&cond);return 0;}

接下来实现一下环形队列的生产者和消费者：

#include<stdio.h>#include<semaphore.h>#include<pthread.h>#include<unistd.h>#include<stdlib.h>#define _SIZE_ 64int Buf[_SIZE_];sem_t semBlank;//定义格子sem_t semData;//定义格子里面的数据sem_t proLock;//生产者之间的互斥sem_t conLock;//消费者之间的互斥void *Consumer(void *arg)//定义消费者{pthread_detach(pthread_self());static int i = 0;int id=(int)arg;while(1){usleep(1000);sem_wait(&semData);sem_wait(&conLock);printf("消费者%d消费了：%d,tid: %1u\n",id,Buf[i++],pthread_self());i%= _SIZE_;sem_post(&conLock);sem_post(&semBlank);}}void *Producter(void *arg)//定义生产者{pthread_detch(pthread_self());static int i = 0;int id=(int)arg;while(1){sleep(1);sem_wait(&semBlank);//对临界区数据进行p操作sem_wait(&proLock);//对生产者互斥锁进行P操作int num = rand()%10;Buf[i+1]=num;prntf("生产者%d生产了：%d,tid:%1u\n",id,num,pthread_self());i%= _SIZE_;sem_post(&proLock);//对生产者互斥锁进行v操作sem_post(&semData);//对临界区资源进行v操作}}int main(){pthread_t con0,con1,pro0,pro1;sem_init(&semData,0,0);sem_init(&semBlank,0,_SIZE_);sem_init(&proLock,0,1);sem_init(&conLock,0,1);int i=0;pthread_creat(&pro0,NULL,Producter,(void*)i);pthread_creat(&con0,NULL,Consumer,(void*)i);i=1;pthread_creat(&pro1,NULL,Producter,(void*)i);pthread_creat(&con1,NULL,Consumer,(void*)i);sem_destroy(&semBlank);sem_destroy(&semData);pthread_join(pro0,NULL);pthread_join(con0,NULL);return 0;}