存储器的分配与回收算法实现.doc

实验内容：模拟操作系统的主存分配，运用可变分区的存储管理算法设计主存分配和回收程序，并不实际启动装入作业。采用最先适应法、最佳适应法、最坏适应法分配主存空间。当一个新作业要求装入主存时，必须查空闲区表，从中找出一个足够大的空闲区。若找到的空闲区大于作业需要量，这是应把它分成二部分，一部分为占用区，加一部分又成为一个空闲区。当一个作业撤离时，归还的区域如果与其他空闲区相邻，则应合并成一个较大的空闲区，登在空闲区表中。运行所设计的程序，输出有关数据结构表项的变化和内存的当前状态。实验要求：详细描述实验设计思想、程序结构及各模块设计思路；详细描述程序所用数据结构及算法；明确给出测试用例和实验结果；为增加程序可读性，在程序中进行适当注释说明；认真进行实验总结，包括：设计中遇到的问题、解决方法与收获等；实验报告撰写要求结构清晰、描述准确逻辑性强；【实验过程记录（源程序、测试用例、测试结果及心得体会等）】#include<stdio.h>#include<malloc.h>#define NULL 0#define LEN1 sizeof(struct job)/作业大小#define LEN2 sizeof(struct idle)/空闲区单元大小#define LEN3 sizeof(struct allocate)/已分配区单元大小int SPACE=100;/定义内存空间大小int ORIGI=1;/定义内存起始地址struct job/定义作业int name;int size;int address;struct idle/定义空闲区int size;int address;struct idle *next;struct allocate/定义已分配区int name;int size;int address;struct allocate *next;struct idle *creatidle(void)/建立空闲表struct idle *head;struct idle *p1;p1=(struct idle*)malloc(LEN2);p1->size=SPACE;p1->address=ORIGI;p1->next=NULL;head=p1;return(head);struct allocate *creatallocate(void)/建立已分配表struct allocate *head;head=NULL;return(head);struct job *creatjob(void)/建立作业struct job *p;p=(struct job*)malloc(LEN1);printf("请输入要运行的作业的名称与大小:n");scanf("%d%d",&p->name,&p->size);return(p);struct idle *init1(struct idle *head,struct job *p)/首次适应算法分配内存struct idle *p0,*p1;struct job *a;a=p;p0=head; p1=p0;while(p0->next!=NULL&&p0->size<a->size)p0=p0->next;if(p0->size>a->size)p0->size=p0->size-a->size;a->address=p0->address;p0->address=p0->address+a->size;elseprintf("无法分配n");return(head);struct idle *init2(struct idle *head,struct job *p)/最优struct idle *p0,*p1;struct job *a;a=p;p0=head; if(p0=NULL) printf("无法进行分配!n");while(p0->next!=NULL&&p0->size<a->size)p0=p0->next; if(p0->size>a->size) p1=p0; p0=p0->next;else printf("无法分配!n");while(p0!=NULL)if(p0->size>p1->size)p0=p0->next;else if(p0->size<p1->size)&&(p0->size>a->size)p1=p0;p0=p0->next;p1->size=(p1->size)-(a->size);a->address=p1->address;p1->address=(p1->address)+(a->size);return(head);struct idle *init3(struct idle *head,struct job *p)/最差struct idle *p0,*p1;struct job *a;a=p;p0=head; if(p0=NULL)printf("无法进行分配!");while(p0->next!=NULL&&p0->size<a->size)p0=p0->next;if(p0->size>a->size) p1=p0; p0=p0->next;elseprintf("无法分配!n");while(p0!=NULL) if(p0->size<p1->size)p0=p0->next;else if(p0->size>p1->size)p1=p0;p0=p0->next;p1->size=(p1->size)-(a->size);a->address=p1->address;p1->address=(p1->address)+(a->size);return(head);struct allocate *reallocate(struct allocate *head,struct job *p)/重置已分配表struct allocate *p0,*p1,*p2;/*p3,*p4;struct job *a;/struct idle *b;a=p;p0=(struct allocate*)malloc(LEN3);p1=(struct allocate*)malloc(LEN3);if(head=NULL)p0->name=a->name;p0->size=a->size;p0->address=ORIGI;p0->next=NULL;head=p0;Else p1->name=a->name;p1->size=a->size;p1->address=a->address;p2=head;while(p2->next!=NULL) p2=p2->next; p2->next=p1;p1->next=NULL;return(head);struct allocate *del(struct allocate *head,struct job *p)/删除指定的作业struct job *p1;struct allocate *p2,*p3;p2=head;p1=p;while(p1->name!=p2->name)&&(p2->next!=NULL)p3=p2;p2=p2->next;if(p1->name=p2->name)if(p2=head)head=p2->next;elsep3->next=p2->next;return(head);struct job *delejob(struct allocate *head)struct job *p1;struct allocate *p2;int num;p1=(struct job*)malloc(LEN1);printf("请输入要删除的作业的名称n");scanf("%d",&num);p2=head; while(num!=p2->name)&&(p2->next!=NULL)p2=p2->next; if(num=p2->name)p1->name=p2->name;p1->size=p2->size;p1->address=p2->address;return(p1);struct idle *unite(struct job *p,struct idle *head)/合并相邻内存空间struct idle *p1,*p2,*p3;struct job *m;m=p;p1=head;p3=(struct idle*)malloc(LEN2);while(p1->address<m->address)&&(p1->next!=NULL)p2=p1;p1=p1->next;if(m->address<p1->address)if(head=p1)p3->size=m->size;p3->address=m->address;if(p1->address-p3->address)=(p3->size)p1->address=p3->address;p1->size=p3->size+p1->size; elsehead=p3;p3->next=p1;elsep3->size=m->size;p3->address=m->address;if(p1->address-p3->address)=(p3->size)p1->address=p3->address;p1->size=p3->size+p1->size;if(p3->address-p2->address)=(p2->size)p2->size=p1->size+p2->size;p2->next=p1->next;elsep2->next=p1;elseif(p3->address-p2->address)=(p2->size)p2->size=p2->size+p3->size;elsep3->next=p1;p2->next=p3;elsep3->size=m->size;p3->address=m->address;if(p3->address-p1->address)=(p1->size)p1->size=p1->size+p3->size; elsep1->next=p3;p3->next=NULL;return(head);void print(struct idle *h1,struct allocate *h2)struct idle *m1;struct allocate *n1;m1=h1;n1=h2;if(m1=NULL)printf("空闲表为空!n");elsewhile(m1!=NULL)printf("空闲单元地址为%d,其大小为%dn",m1->address,m1->size);m1=m1->next;if(n1=NULL)printf("已分配表为空!n");elsewhile(n1!=NULL)printf("已分配单元地址为%d,其大小为%d,其名称为%dn",n1->address,n1->size,n1->name);n1=n1->next; void FF(void)struct idle *p1;struct allocate *p2;struct job *p,*q;int y=1;int n=0;int a=1;int c;p1=creatidle();p2=creatallocate();printf("初始情况为:n");print(p1,p2);while(a=y)printf("请输入要进行的操作:1.建立作业 2.删除作业 3.结束操作n");scanf("%d",&c);switch(c)case 1:p=creatjob();p1=init1(p1,p);p2=reallocate(p2,p);print(p1,p2);break;case 2: q=delejob(p2);p2=del(p2,q);/p2=reallocate(p2,q);p1=unite(q,p1);print(p1,p2);break;case 3:y=0;break;void BF(void)struct idle *p1;struct allocate *p2;struct job *p,*q;int y=1;int n=0;int a=1;int c;p1=creatidle();p2=creatallocate();printf("初始情况为:n");print(p1,p2);while(a=y)printf("请输入要进行的操作:1.建立作业 2.删除作业 3.结束操作n");scanf("%d",&c);switch(c)case 1:p=creatjob();p1=init2(p1,p);p2=reallocate(p2,p);print(p1,p2);break;case 2: q=delejob(p2);p2=del(p2,q);/p2=reallocate(p2,q);p1=unite(q,p1);print(p1,p2);break;case 3:y=0;break;void WF(void)struct idle *p1;struct allocate *p2;struct job *p,*q;int y=1;int n=0;int a=1;int c;p1=creatidle();p2=creatallocate();printf("初始情况为:n");print(p1,p2);while(a=y)printf("请输入要进行的操作:1.建立作业 2.删除作业 3.结束操作n");scanf("%d",&c);switch(c)case 1:p=creatjob();p1=init3(p1,p);p2=reallocate(p2,p);print(p1,p2);break;case 2: q=delejob(p2);p2=del(p2,q);/p2=reallocate(p2,q);p1=unite(q,p1);print(p1,p2);break;case 3:y=0;break;运行结果如下1.首次适应算法建立作业2.最优适应算法建立作业3.最差适应算法建立并删除作业