固定分区存储管理文档

/*固定分区分配的最佳分配算法模拟*/ #include<stdio.h> #include<graphics.h> #include<string.h> #include<stdlib.h> /*定义分区表结构*/ struct areaTable { int start;//起始地址长度以及状态 int length; int state; }; /*****************/ /*手动分区表*/ int initAT(struct areaTable* at,int n) { int i;/*for loop*/ printf("Please Allocate The Memory By Yourselt:\n");//划分内存固定大小分区 for(i=0;i<n;i++) { printf("Input the %d-area length:",i);//输入固定分区每个的长度 scanf("%d",&at[i].length); if(i==0) at[i].start=40;//定义第一个分区的起始地址为40 else at[i].start=at[i-1].start+at[i-1].length;//表示下一个起始地址的起始状态表示的是分区长度加上起始地址长度 at[i].state=0;//表示状态为未分配 } return 0; } /*****************/ /*根据分区表画图*/ int optiAlloc(struct areaTable* at,int n,int ask) { int difference=1000; int areaNo=-1; int i; for(i=0;i<n;i++) { if(at[i].state==0&&at[i].length>=ask&&((at[i].length-ask)<difference)) { difference=at[i].length-ask; areaNo=i; } } return areaNo; } /*****************/ /*根据分区表画图*/ int drawAT(struct areaTable* at,int n) { int gdriver,gmode; int i=0; int left,right; char str10[10]; char str40[40]; /*设定图形模式*/ detectgraph(&gdriver,&gmode); initgraph(&gdriver,&gmode,"c:\\tc"); /*画图*/ left = getmaxx() / 2 - 50; right = getmaxx() / 2 + 50; setcolor(2); setfillstyle(SOLID_FILL,6); rectangle(left,50,right,50+at[0].start); floodfill(left+2,50+2,2); outtextxy(right+5,50,"system area len=50"); setcolor(2); setfillstyle(SOLID_FILL,4); for(i=0;i<n;i++) { rectangle(left,50+at[i].start,right,50+at[i].start+at[i].length); if(at[i].state==1) floodfill(left+2,50+at[i].start+2,2); if(at[i].state!=0) floodfill(left+2,50+at[i].start+2,2); itoa(i,str10,10); strcpy(str40,str10); strcat(str40," len="); itoa(at[i].length,str10,10); strcat(str40,str10); strcat(str40,at[i].state?" FULL":" FREE"); outtextxy(right+5,50+at[i].start,str40); } /*暂停屏幕并关闭图形模式*/ getch(); clrscr(); closegraph(); return 0; } /*****************/ void main() { struct areaTable* at; int ask; int n; int allocNo=-1; char ch=' '; clrscr(); printf("Input how many area you allocate:"); scanf("%d",&n); at=(struct areaTable*)malloc(n*sizeof(struct areaTable)); initAT(at,n); drawAT(at,n); do{ printf("\nInput the mem length you want:"); scanf("%d",&ask);//表示的是输入分区长度 allocNo = optiAlloc(at,n,ask); if(allocNo!=-1) { printf("Allocate Successfully!\n"); at[allocNo].state=1; drawAT(at,n); } else { printf("Allocate Failed"); } printf("\ndo you want contimue to allocate(Y or N):"); ch=getch(); putch(ch); }while(ch=='Y'||ch=='y'); free(at); getch(); }