用多线程同步方法解决生产者-消费者问题(操作系统课设)题目用多线程同步方法解决生产者－消费者问题(Producer-Consume r Problem)学院物理学与电子信息工程学院专业电子信息工程班级08电信本一班姓名指导教师2010 年12 月日目录目录 0课程设计任务书 (1)正文 (3)1.设计目的与要求 (3)1.1设计目的 (3)1.2设计要求 (3)2.设计思想及系统平台 (3)2.1设计思想 (3)2.2系统平台及使用语言 (3)3.详细算法描述 (4)4.源程序清单 (7)5.运行结果与运行情况 (12)6.调试过程 (16)7.总结 (16)课程设计任务书题目: 用多线程同步方法解决生产者－消费者问题 (Producer-Consumer Problem)初始条件：1．操作系统：Linux2．程序设计语言：C语言3．有界缓冲区内设有20个存储单元，其初值为0。

放入／取出的数据项按增序设定为1－20这20个整型数。

要求完成的主要任务:（包括课程设计工作量及其技术要求，以及说明书撰写等具体要求）1．技术要求：1）为每个生产者／消费者产生一个线程，设计正确的同步算法2）每个生产者和消费者对有界缓冲区进行操作后，即时显示有界缓冲区的当前全部内容、当前指针位置和生产者／消费者线程的自定义标识符。

3）生产者和消费者各有两个以上。

4）多个生产者或多个消费者之间须共享对缓冲区进行操作的函数代码。

2．设计说明书内容要求：1)设计题目与要求2)总的设计思想及系统平台、语言、工具等。

3）数据结构与模块说明（功能与流程图）4）给出用户名、源程序名、目标程序名和源程序及其运行结果。

（要注明存储各个程序及其运行结果的主机IP地址和目录。

）5）运行结果与运行情况（提示: （1）有界缓冲区可用数组实现。

（2）编译命令可用：cc -lpthread-o 目标文件名源文件名（3）多线程编程方法参见附件。

）3. 调试报告：1)调试记录2)自我评析和总结正文1.设计目的与要求1.1设计目的通过研究Linux的线程机制和信号量实现生产者消费者问题(Producer-Consumer Problem)的并发控制。

1.2设计要求1）为每个生产者／消费者产生一个线程，设计正确的同步算法2）每个生产者/消费者对该存储区进行操作后，即时显示该存储区的全部内容、当前指针位置和生产者/消费者线程的自定义标识符。

3）生产者和消费者各有两个以上。

4）多个生产者/消费者之间须共享对存储区进行操作的函数代码。

2.设计思想及系统平台2.1设计思想在本问题中,共需要一个Mutex和两个Semaphore.其中,Mutex是用来锁定临界区的,以解决对共享数据buffer的互斥访问问题(无论是对生成者还是对消费者);我们共需要两个Semaphore,这是因为在本问题中共有两个稀缺资源.第一种是"非空"这种资源,是在消费者之间进行竞争的.第二种是"非满"这种资源,是在生产者之间进行竞争的.所以,一般来说,需要锁定临界区,就需要Mutex;有几种稀缺资源就需要几个Semaphore.对稀缺资源的分析不能想当然.稀缺资源不一定是指被共享的资源,很多时候是指线程会被阻塞的条件(除了要进临界区被阻塞外).在生产者消费者问题中,消费者会在缓冲区为空时被阻塞,所以"非空"是一种稀缺资源;需要设置一个信号量consumer_semaphore,初值设为0;生产者会在缓冲区为满时被阻塞,所以"非满"也是一种稀缺资源.需要设置一个信号量producer_semaphore,初值设为buffer的大小MAX_BUFFER2.2系统平台及使用语言本课程设计在Linux操作系统下，使用C语言完成。

用到的工具主要有GCC 编译器和VI编辑器。

3.详细算法描述共享数据：Semaphore buffer_mutex=1；Semaphore producer_semaphore=MAX_BUFFER；Semaphore consumer_semaphore=0；int buffer[MAX_BUFFER];Producer线程的处理函数：while(1){Wait(producer_semaphore);Wait(buffer_mutex);Buffer[pn]=product;pn=(pn+1)%MAX_BUFFER;Signal(consumer_semaphore);Signal(buffer_mutex);Sleep();}producer线程的处理函数流程图如下：consumer线程的处理函数:while(1){Wait(consumer_semaphore);Wait(buffer_mutex);Consume=buffer[cn];cn=(cn+1)%MAX_BUFFER;Signal(producer_semaphore);Signal(buffer_mutex);Sleep();}consumer线程的处理函数流程图如下：4.源程序清单用户名：rj070126（IP：192.168.2.254）源程序名：/home/rj070126/pc.c目标程序名：/home/rj070126/pc运行结果：/home/rj070126/output.txt源程序清单如下：#include<stdio.h>#include<stdlib.h>#include<string.h>#include<pthread.h>#include<semaphore.h>#include<sys/types.h>#include<errno.h>#include<unistd.h>#include<signal.h>#include<time.h>//生产者的个数#define NUM_THREADS_P 5//消费者的个数#define NUM_THREADS_C 5//缓冲区的大小#define MAX_BUFFER 20//运行的时间#define RUN_TIME 20//缓冲区的数组int buffer[MAX_BUFFER];int produce_pointer=0,consume_pointer=0;sem_t producer_semaphore,consumer_semaphore,buffer_mutex;pthread_t threads_p[NUM_THREADS_P]; /*producer*/pthread_t threads_c[NUM_THREADS_C]; /*consumer*/FILE* fd;void *producer_thread(void *tid);void *consumer_thread(void *tid);void showbuf();void handler(){int i;for(i=0;i<NUM_THREADS_P;i++)//送终止信号给thread线程，如果成功则返回0，否则为非0值。

发送成功并不意味着thread //会终止。

pthread_cancel(threads_p[i]);for(i=0;i<NUM_THREADS_C;i++)pthread_cancel(threads_c[i]);}int main(){int i;signal(SIGALRM,handler);fd=fopen("output.txt","w"); /*open a file to save the result*/sem_init(&producer_semaphore,0,MAX_BUFFER); /*set the value of semaphores*/sem_init(&consumer_semaphore,0,0);sem_init(&buffer_mutex,0,1);for(i=0;i<MAX_BUFFER;i++)buffer[i]=0; /*initiate the buffer*//*create the threads*/for(i=0;i<NUM_THREADS_P;i++)pthread_create(&threads_p[i],NULL,(void*)producer_thread,(void*)(i+1));for(i=0;i<NUM_THREADS_C;i++)pthread_create(&threads_c[i],NULL,(void*)consumer_thread,(void *)(i+1));alarm(RUN_TIME); /*set time to run*//*wait the threads to exit*/for(i=0;i<NUM_THREADS_P;i++)pthread_join(threads_p[i],NULL);for(i=0;i<NUM_THREADS_C;i++)pthread_join(threads_c[i],NULL);/*destroy the semaphores*/sem_destroy(&producer_semaphore);sem_destroy(&consumer_semaphore);sem_destroy(&buffer_mutex);fclose(fd);return 0;}void *producer_thread(void *tid){/*the thread can be canceled by other thread*/pthread_setcancelstate(PTHREAD_CANCEL_ENABLE,NULL);while(1){sem_wait(&producer_semaphore);srand((int)time(NULL)*(int)tid);sleep(rand()%2+1); /*one or two seconds to produce*/while((produce_pointer+1)%20==consume_pointer);sem_wait(&buffer_mutex);buffer[produce_pointer]=rand()%20+1;produce_pointer=(produce_pointer+1)%20;if(produce_pointer==0){ /*if buffer was filled to the 19th*/printf("producer:%d pointer_p:%2d produced:%2d\n",(int)tid,19,buffer[19]);fprintf(fd,"producer:%d pointer_p:%2d produced:%2d\n",(int)tid,19,buffer[19]);}else{printf("producer:%d pointer_p:%2d produced:%2d\n",(int)tid,produce_pointer-1,buffer[produce_pointer-1]);fprintf(fd,"producer:%d pointer_p:%2d produced:%2d\n",(int)tid,produce_pointer-1,buffer[produce_pointer-1]);}showbuf();sem_post(&buffer_mutex);sem_post(&consumer_semaphore); /*inform the consumer the buffer is not empty*/srand((int)time(NULL)*(int)tid);sleep(rand()%5+1); /*wait a few seconds ,then continue producing*/ }return ((void*)0);}void *consumer_thread(void *tid){/*the thread can be canceled by other thread*/pthread_setcancelstate(PTHREAD_CANCEL_ENABLE,NULL);while(1){//信号等待sem_wait(&consumer_semaphore);//获取种子srand((int)time(NULL)*(int)tid);//休眠一到两秒sleep(rand()%2+1); /*one or two seconds to consume*/sem_wait(&buffer_mutex);printf("consumer:%d pointer_c:%2d consumed:%2d\n",(int)tid,consume_pointer,buffer[consume_pointer]);fprintf(fd,"consumer:%d pointer_c:%2d consumed:%2d\n",(int)tid,consume_pointer,buffer[consume_pointer]);buffer[consume_pointer]=0;consume_pointer=(consume_pointer+1)%20;showbuf();sem_post(&buffer_mutex);sem_post(&producer_semaphore);srand((int)time(NULL)*(int)tid);sleep(rand()%5+1); /*wait a few seconds ,then continue consuming*/ }return ((void*)0);}/*show the content of buffer*/void showbuf(){int i;printf("buffer:");fprintf(fd,"buffer:");for(i=0;i<MAX_BUFFER;i++){printf("%2d ",buffer[i]);fprintf(fd,"%2d ",buffer[i]);}printf("\n\n");fprintf(fd,"\n\n");}5.运行结果与运行情况程序运行结果如下：producer:1 pointer_p: 0 produced:20buffer:20 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0producer:3 pointer_p: 1 produced:13buffer:20 13 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0producer:2 pointer_p: 2 produced: 6buffer:20 13 6 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0producer:4 pointer_p: 3 produced:14buffer:20 13 6 14 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0producer:5 pointer_p: 4 produced:20buffer:20 13 6 14 20 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0consumer:2 pointer_c: 0 consumed:20buffer: 0 13 6 14 20 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0producer:1 pointer_p: 5 produced:20buffer: 0 13 6 14 20 20 0 0 0 0 0 0 0 0 0 0 0 0 0 0consumer:1 pointer_c: 1 consumed:13buffer: 0 0 6 14 20 20 0 0 0 0 0 0 0 0 0 0 0 0 0 0consumer:3 pointer_c: 2 consumed: 6buffer: 0 0 0 14 20 20 0 0 0 0 0 0 0 0 0 0 0 0 0 0 consumer:4 pointer_c: 3 consumed:14buffer: 0 0 0 0 20 20 0 0 0 0 0 0 0 0 0 0 0 0 0 0consumer:5 pointer_c: 4 consumed:20buffer: 0 0 0 0 0 20 0 0 0 0 0 0 0 0 0 0 0 0 0 0producer:3 pointer_p: 6 produced: 1buffer: 0 0 0 0 0 20 1 0 0 0 0 0 0 0 0 0 0 0 0 0producer:2 pointer_p: 7 produced:14buffer: 0 0 0 0 0 20 1 14 0 0 0 0 0 0 0 0 0 0 0 0consumer:3 pointer_c: 5 consumed:20buffer: 0 0 0 0 0 0 1 14 0 0 0 0 0 0 0 0 0 0 0 0producer:4 pointer_p: 8 produced: 6buffer: 0 0 0 0 0 0 1 14 6 0 0 0 0 0 0 0 0 0 0 0consumer:5 pointer_c: 6 consumed: 1buffer: 0 0 0 0 0 0 0 14 6 0 0 0 0 0 0 0 0 0 0 0producer:5 pointer_p: 9 produced: 8buffer: 0 0 0 0 0 0 0 14 6 8 0 0 0 0 0 0 0 0 0 0consumer:2 pointer_c: 7 consumed:14buffer: 0 0 0 0 0 0 0 0 6 8 0 0 0 0 0 0 0 0 0 0consumer:5 pointer_c: 8 consumed: 6buffer: 0 0 0 0 0 0 0 0 0 8 0 0 0 0 0 0 0 0 0 0producer:1 pointer_p:10 produced:18buffer: 0 0 0 0 0 0 0 0 0 8 18 0 0 0 0 0 0 0 0 0consumer:1 pointer_c: 9 consumed: 8buffer: 0 0 0 0 0 0 0 0 0 0 18 0 0 0 0 0 0 0 0 0producer:2 pointer_p:11 produced:10buffer: 0 0 0 0 0 0 0 0 0 0 18 10 0 0 0 0 0 0 0 0producer:4 pointer_p:12 produced:10buffer: 0 0 0 0 0 0 0 0 0 0 18 10 10 0 0 0 0 0 0 0consumer:4 pointer_c:10 consumed:18buffer: 0 0 0 0 0 0 0 0 0 0 0 10 10 0 0 0 0 0 0 0producer:3 pointer_p:13 produced: 3buffer: 0 0 0 0 0 0 0 0 0 0 0 10 10 3 0 0 0 0 0 0consumer:3 pointer_c:11 consumed:10buffer: 0 0 0 0 0 0 0 0 0 0 0 0 10 3 0 0 0 0 0 0consumer:2 pointer_c:12 consumed:10buffer: 0 0 0 0 0 0 0 0 0 0 0 0 0 3 0 0 0 0 0 0producer:1 pointer_p:14 produced: 6buffer: 0 0 0 0 0 0 0 0 0 0 0 0 0 3 6 0 0 0 0 0consumer:1 pointer_c:13 consumed: 3buffer: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 6 0 0 0 0 0producer:2 pointer_p:15 produced:18buffer: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 6 18 0 0 0 0consumer:5 pointer_c:14 consumed: 6buffer: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 18 0 0 0 0producer:1 pointer_p:16 produced: 6buffer: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 18 6 0 0 0producer:3 pointer_p:17 produced:19buffer: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 18 6 19 0 0consumer:1 pointer_c:15 consumed:18buffer: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 6 19 0 0producer:5 pointer_p:18 produced: 7buffer: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 6 19 7 0consumer:3 pointer_c:16 consumed: 6buffer: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 19 7 0producer:4 pointer_p:19 produced:14buffer: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 19 7 14consumer:5 pointer_c:17 consumed:19buffer: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 7 14consumer:4 pointer_c:18 consumed: 7buffer: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 14producer:1 pointer_p: 0 produced: 4buffer: 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 14consumer:2 pointer_c:19 consumed:14buffer: 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0consumer:1 pointer_c: 0 consumed: 4buffer: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0producer:2 pointer_p: 1 produced:15buffer: 0 15 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0producer:3 pointer_p: 2 produced:13buffer: 0 15 13 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0producer:2 pointer_p: 3 produced: 3buffer: 0 15 13 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0说明：“producer:2”是指自定义标号为2的producer，“pointer_p:3”是指该producer 的指针，“produced:3”是指该producer在buffer[3]里写入3，“buffer: 0 15 13 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ”是指该producer进行写操作后存储区的内容。