东北大学-操作系统实验三报告

1、精选优质文档-倾情为你奉上操作系统实验报告班 级物联网1302班学 号姓 名实验3 进程同步和通信-生产者和消费者问题模拟1. 目的： 调试、修改、运行模拟程序，通过形象化的状态显示，使学生理解进程的概念，了解同步和通信的过程，掌握进程通信和同步的机制，特别是利用缓冲区进行同步和通信的过程。通过补充新功能，使学生能灵活运用相关知识，培养创新能力。2. 内容及要求：1) 调试、运行模拟程序。2) 发现并修改程序中不完善的地方。3) 修改程序，使用随机数控制创建生产者和消费者的过程。4) 在原来程序的基础上，加入缓冲区的写互斥控制功能，模拟多个进程存取一个公共缓冲区，当有进程正在写缓冲区时，其他要

2、访问该缓冲区的进程必须等待，当有进程正在读取缓冲区时，其他要求读取的进程可以访问，而要求写的进程应该等待。5) 完成1)、2)、3）功能的,得基本分,完成4)功能的加2分,有其它功能改进的再加2分3. 程序说明：本程序是模拟两个进程，生产者（producer）和消费者(Consumer)工作。生产者每次产生一个数据，送入缓冲区中。消费者每次从缓冲区中取走一个数据。缓冲区可以容纳8个数据。因为缓冲区是有限的，因此当其满了时生产者进程应该等待，而空时，消费者进程应该等待；当生产者向缓冲区放入了一个数据，应唤醒正在等待的消费者进程，同样，当消费者取走一个数据后，应唤醒正在等待的生产者进程。就是生产者

3、和消费者之间的同步。每次写入和读出数据时，都将读和写指针加一。当读写指针同样时，又一起退回起点。当写指针指向最后时，生产者就等待。当读指针为零时，再次要读取的消费者也应该等待。 为简单起见，每次产生的数据为0-99的整数，从0开始，顺序递增。两个进程的调度是通过运行者使用键盘来实现的。4. 程序使用的数据结构进程控制块：包括进程名，进程状态和执行次数。缓冲区：一个整数数组。缓冲区说明块：包括类型，读指针，写指针，读等待指针和写等待指针。5. 程序使用说明启动程序后，如果使用'p'键则运行一次生产者进程，使用'c'键则运行一次消费者进程。通过屏幕可以观察到两个进程

4、的状态和缓冲区变化的情况。6. 实验流程图源程序#include<>#include<>#include<>#define PIPESIZE 8enum Status RUN, WAIT, READY ;#define NORMAL 0#define SLEEP 1#define AWAKE 2struct PCBchar name3;enum Status status;int time;struct waitqueuestruct PCB pcb;struct waitqueue *next;struct PCB *producer; /* write

5、wait point */struct PCB *consumer;/* read wait point */struct waitqueue *headerqueue, *tailqueue;int writeptr;int readptr;int writein, readout;int bufferPIPESIZE;int empty, full;void runp(char in3), runc(char in3), print();int main()char in3;writeptr = 0;readptr = 0;writein = 0;empty = PIPESIZE;full

6、 = 0;producer = (struct PCB *)malloc(sizeof(struct PCB);consumer = (struct PCB *)malloc(sizeof(struct PCB);headerqueue = (struct waitqueue *)malloc(sizeof(struct waitqueue);headerqueue->next = NULL;tailqueue = headerqueue;producer->status = READY;consumer->status = WAIT;producer->time =

7、consumer->time = 0;printf("Now starting the program!n");printf("Press 'p1' to run PRODUCER1,Press 'p1' to run PRODUCER2 n");printf("Press 'c1' to run CONSUMER1,Press 'c2' to run CONSUMER2 n");printf("Press 'e' to exit from

8、 the program.n");while (1)strcpy(in, "N");while (!strcmp(in, "N")printf("n");scanf("%s", in);if (strcmp(in, "e") && strcmp(in, "p1") && strcmp(in, "p2") && strcmp(in, "c1") && strcmp(

9、in, "c2")printf("error,please input again!n");strcpy(in, "N");if ('p' = in0)runp(in);producer->time+;else if ('c' = in0)runc(in);consumer->time+;elsen", in);struct waitqueue *p = (struct waitqueue *)malloc(sizeof(struct waitqueue);strcpy(p->

10、;, in);p-> = WAIT;p-> = producer->time + 1;p->next = NULL;tailqueue->next = p;tailqueue = p;full+;elsewritein = (writein + 1) % 100;producer->status = RUN;printf("run PRODUCER %s process . product %d ", in, writein);bufferwriteptr = writein;if (empty>8)struct waitqueue

11、 *p;p = headerqueue->next;printf("run CONSUMER %s process. use %d", p->, bufferwriteptr);if (tailqueue = p)tailqueue = headerqueue;headerqueue->next = p->next;free(p);consumer->status = WAIT;empty-;elseif (writeptr > readptr)writeptr+;if (writeptr >= PIPESIZE)writeptr

12、= 0;if (readptr = 0)producer->status = WAIT;else producer->status = READY;elsewriteptr+;if (writeptr = readptr)producer->status = WAIT;else producer->status = READY;consumer->status = READY;empty-;full+;void runc(char in3)if (empty >= 8)struct waitqueue *search;search = headerqueue

13、->next;while (search != NULL)if (!strcmp(in, search->)printf("error!n");exit(1);search = search->next;consumer->status = WAIT;printf("CONSUMER %s is waiting, can't be scheduled.n",in);struct waitqueue *p = (struct waitqueue *)malloc(sizeof(struct waitqueue);strcpy

14、(p->, in);p-> = WAIT;p-> = consumer->time + 1;p->next = NULL;tailqueue->next = p;tailqueue = p;empty+;elseconsumer->status = RUN;readout = bufferreadptr;printf("run CONSUMER %s process. use %d ", in, readout);if (full>8)writein = (writein + 1) % 100;bufferwriteptr =

15、 writein;struct waitqueue *p;p = headerqueue->next;printf("run PRODUCER %s process. product %d ", p->, bufferwriteptr);if (tailqueue = p)tailqueue = headerqueue;headerqueue->next = p->next;free(p);producer->status = WAIT;full-;writeptr+;readptr+;elseif (readptr > writeptr

16、)readptr+;if (readptr >= PIPESIZE)readptr = 0;if (writeptr = 0)consumer->status = WAIT;elseconsumer->status = READY;else consumer->status = READY;elsereadptr+;if (readptr = writeptr)consumer->status = WAIT;writeptr = readptr = 0;else consumer->status = READY;producer->status = R

17、EADY;full-;empty+;void print()int i = 0;int j = 0;int low = 0;int high = 0;printf("n");for (i; i < PIPESIZE; i+)printf("-");printf("n");if (readptr < writeptr)for (low = 0; low < readptr; low+)printf("|");for (low = readptr; low < writeptr; low+)pr

18、intf("| %2d|", bufferlow);for (low = writeptr; low <PIPESIZE; low+)printf("|");else if (readptr > writeptr)for (low = 0; low < writeptr; low+)printf("| %2d|", bufferlow);for (low = writeptr; low < readptr; low+)printf("|");for (low = readptr; low < PIPESIZE; low+)printf("| %2d|", bufferlow);else if (producer->status = WAIT)for (low = 0; low < PIPESIZE; low+)printf("| %2d |", bufferlow);elsefor (low = 0; low < PIPESIZE; l