操作系统源代码-刘坤鹏.doc

1、操作系统源代码-刘坤鹏#include #include #include #define MEM_D_SIZE 1024*1024 /总磁盘空间为 1M#define DISKSIZE 1024 /磁盘块的大小 1K#define DISK_NUM 1024 /磁盘块数目 1K#define FATSIZE DISK_NUM*sizeof(struct fatitem) /FAT表大小#define ROOT_DISK_NO FATSIZE/DISKSIZE+1 /根目录起始盘块号#define ROOT_DISK_SIZE sizeof(struct direct) /根目录大小#defi

2、ne DIR_MAXSIZE 1024 /路径最大长度为 1KB#define MSD 5 /最大子目录数 5#define MOFN 5 /最大文件深度为 5#define MAX_WRITE 1024*128 /最大写入文字长度 128KB struct fatitem /* size 8*/ int item; /*存放文件下一个磁盘的指针*/ char em_disk; /*磁盘块是否空闲标志位 0 空闲*/ ; struct direct /*-文件控制快信息-*/ struct FCB char name9; /*文件/目录名 8 位*/ char property; /*属性 1

3、 位目录 0 位普通文件*/ int size; /*文件/目录字节数、盘块数)*/ int firstdisk; /*文件/目录 起始盘块号*/ int next; /*子目录起始盘块号*/ int sign; /*1是根目录 0 不是根目录*/ directitemMSD+2; ; struct opentable struct openttableitem char name9; /*文件名*/ int firstdisk; /*起始盘块号*/ int size; /*文件的大小*/ openitemMOFN; int cur_size; /*当前打文件的数目*/ ; struct fa

4、titem *fat; /*FAT表*/ struct direct *root; /*根目录*/ struct direct *cur_dir; /*当前目录*/ struct opentable u_opentable; /*文件打开表*/ int fd=-1; /*文件打开表的序号*/ char *bufferdir; /*记录当前路径的名称*/ char *fdisk; /*虚拟磁盘起始地址*/ void initfile(); void format(); void enter(); void halt(); int create(char *name); int open(char

5、 *name); int close(char *name); int write(int fd,char *buf,int len); int read(int fd,char *buf); int del(char *name); int mkdir(char *name); int rmdir(char *name); void dir(); int cd(char *name); void print(); void show(); void initfile() fdisk = (char *)malloc(MEM_D_SIZE*sizeof(char); /*申请 1M空间*/ f

6、ormat(); void format() int i; FILE *fp; fat = (struct fatitem *)(fdisk+DISKSIZE); /*计算 FAT表地址，引导区向后偏移 1k)*/ /*-初始化 FAT表-*/ fat0.item=-1; /*引导块*/ fat0.em_disk=1; for(i=1;idirectitem0.sign = 1; root-directitem0.firstdisk = ROOT_DISK_NO; strcpy(root-directitem0.name,“.“); root-directitem0.next = root-d

7、irectitem0.firstdisk; root-directitem0.property = 1; root-directitem0.size = ROOT_DISK_SIZE; /*-指向上一级目录的目录项-*/ root-directitem1.sign = 1; root-directitem1.firstdisk = ROOT_DISK_NO; strcpy(root-directitem1.name,“); root-directitem1.next = root-directitem0.firstdisk; root-directitem1.property = 1; roo

8、t-directitem1.size = ROOT_DISK_SIZE; if(fp = fopen(“disk.dat“,“wb“)=NULL) printf(“Error:n Cannot open file n“); return; for(i=2;idirectitemi.sign = 0; root-directitemi.firstdisk = -1; strcpy(root-directitemi.name,“); root-directitemi.next = -1; root-directitemi.property = 0; root-directitemi.size =

9、0; if(fp = fopen(“disk.dat“,“wb“)=NULL) printf(“Error:n Cannot open file n“); return; if(fwrite(fdisk,MEM_D_SIZE,1,fp)!=1) /*把虚拟磁盘空间保存到磁盘文件中*/ printf(“Error:n File write error! n“); fclose(fp); void enter() FILE *fp; int i; fdisk = (char *)malloc(MEM_D_SIZE*sizeof(char); /*申请 1M空间*/ if(fp=fopen(“dis

10、k.dat“,“rb“)=NULL) printf(“Error:nCannot open filen“); return; if(!fread(fdisk,MEM_D_SIZE,1,fp) /*把磁盘文件 disk.dat 读入虚拟磁盘空间(内存)*/ printf(“Error:nCannot read filen“); exit(0); fat = (struct fatitem *)(fdisk+DISKSIZE); /*找到 FAT表地址*/ root = (struct direct *)(fdisk+DISKSIZE+FATSIZE);/*找到根目录地址*/ fclose(fp)

11、; /*-初始化用户打开表-*/ for(i=0;i8) /*文件名大于 8 位*/ return(-1); for(j=2;jdirectitemj.name,name) break; if(jdirectitemi.firstdisk=-1) break; if(i=MSD+2) /*无空目录项*/ return(-2); if(u_opentable.cur_size=MOFN) /*打开文件太多*/ return(-3); for(j=ROOT_DISK_NO+1;j=DISK_NUM) return(-5); fatj.em_disk = 1; /*将空闲块置为已经分配*/ /*-填

12、写目录项-*/ strcpy(cur_dir-directitemi.name,name); cur_dir-directitemi.firstdisk = j; cur_dir-directitemi.size = 0; cur_dir-directitemi.next = j; cur_dir-directitemi.property = 0; /*-*/ fd = open(name); return 0; int open(char *name) int i, j; for(i=2;idirectitemi.name,name) break; if(i=MSD+2) return(-1

13、); /*-是文件还是目录-*/ if(cur_dir-directitemi.property=1)return(-4); /*-文件是否打开-*/ for(j=0;j=MOFN) /*文件打开太多*/ return(-3); /*-查找一个空闲用户打开表项-*/ for(j=0;jdirectitemi.firstdisk; strcpy(u_opentable.openitemj.name,name); u_opentable.openitemj.size = cur_dir-directitemi.size; u_opentable.cur_size+; /*-返回用户打开表表项的序号

14、-*/ return(j); int close(char *name) int i; for(i=0;i=MOFN) return(-1); /*-清空该文件的用户打开表项的内容-*/ strcpy(u_opentable.openitemi.name,“); u_opentable.openitemi.firstdisk = -1; u_opentable.openitemi.size = 0; u_opentable.cur_size-; return 0; int write(int fd, char *buf, int len) char *first; int item, i, j

15、, k; int ilen1, ilen2, modlen, temp; /*-用 $ 字符作为空格 # 字符作为换行符-*/ char Space = 32; char Endter= n; for(i=0;idirectitemi.firstdisk=item) break; temp = i; /*-存放当前目录项的下标-*/ /*-找到的 item 是该文件的最后一块磁盘块-*/ while(fatitem.item!=-1) item =fatitem.item; /*-查找该文件的下一盘块-*/ /*-计算出该文件的最末地址-*/ first = fdisk+item*DISKSI

16、ZE+u_opentable.openitemfd.size%DISKSIZE; /*-如果最后磁盘块剩余的大小大于要写入的文件的大小-*/ if(DISKSIZE-u_opentable.openitemfd.size%DISKSIZElen) strcpy(first,buf); u_opentable.openitemfd.size = u_opentable.openitemfd.size+len; cur_dir-directitemtemp.size = cur_dir-directitemtemp.size+len; else for(i=0;i0) ilen2 = ilen2+

17、1; /*-还需要多少块磁盘块-*/ for(j=0;j=DISK_NUM) /*-如果磁盘块已经分配完了-*/ return(-1); first = fdisk+i*DISKSIZE; /*-找到的那块空闲磁盘块的起始地址-*/ if(j=ilen2-1) /*-如果是最后要分配的一块-*/ for(k=0;kdirectitemtemp.size = cur_dir-directitemtemp.size+len; return 0; int read(int fd, char *buf) int len = u_opentable.openitemfd.size; char *firs

18、t; int i, j, item; int ilen1, modlen; item = u_opentable.openitemfd.firstdisk; ilen1 = len/DISKSIZE; modlen = len%DISKSIZE; if(modlen!=0) ilen1 = ilen1+1; /*-计算文件所占磁盘的块数-*/ first = fdisk+item*DISKSIZE; /*-计算文件的起始位置-*/ for(i=0;idirectitemi.name,name) break; cur_item = i; /*-用来保存目录项的序号,供释放目录中-*/ if(i=

19、MSD+2) /*-如果不在当前目录中-*/ return(-1); if(cur_dir-directitemcur_item.property!=0) /*-如果删除的(不)是目录-*/ return(-3); for(i=0;idirectitemcur_item.firstdisk;/*-该文件的起始盘块号-*/ while(item!=-1) /*-释放空间,将 FAT表对应项进行修改-*/ temp = fatitem.item; fatitem.item = -1; fatitem.em_disk = 0; item = temp; /*-释放目录项-*/ cur_dir-dir

20、ectitemcur_item.sign = 0; cur_dir-directitemcur_item.firstdisk = -1; strcpy(u_opentable.openitemcur_item.name,“); cur_dir-directitemcur_item.next = -1; cur_dir-directitemcur_item.property = 0; cur_dir-directitemcur_item.size = 0; return 0; int mkdir(char *name) int i,j; struct direct *cur_mkdir; if(

21、!strcmp(name,“.“) return(-4); if(!strcmp(name,“) return(-4); if(strlen(name)8) /*-如果目录名长度大于 8 位-*/ return(-1); for(i=2;idirectitemi.firstdisk=-1) break; if(i=MSD+2) /*-目录/文件 已满-*/ return(-2); for(j=2;jdirectitemj.name,name) break; if(j=DISK_NUM) return(-5); fatj.em_disk=1; /*-将该空闲块设置为已分配-*/ /*-填写目录项

22、-*/ strcpy(cur_dir-directitemi.name,name); cur_dir-directitemi.firstdisk=j; cur_dir-directitemi.size=ROOT_DISK_SIZE; cur_dir-directitemi.next=j; cur_dir-directitemi.property=1; /*-所创目录在虚拟磁盘上的地址(内存物理地址)-*/ cur_mkdir=(struct direct *)(fdisk+cur_dir-directitemi.firstdisk*DISKSIZE); /*-初始化目录-*/ /*-指向当前目

23、录的目录项-*/ cur_mkdir-directitem0.sign=0; cur_mkdir-directitem0.firstdisk=cur_dir-directitemi.firstdisk; strcpy(cur_mkdir-directitem0.name,“.“); cur_mkdir-directitem0.next=cur_mkdir-directitem0.firstdisk; cur_mkdir-directitem0.property=1; cur_mkdir-directitem0.size=ROOT_DISK_SIZE; /*-指向上一级目录的目录项-*/ cur

24、_mkdir-directitem1.sign=cur_dir-directitem0.sign;cur_mkdir-directitem1.firstdisk=cur_dir-directitem0.firstdisk; strcpy(cur_mkdir-directitem1.name,“); cur_mkdir-directitem1.next=cur_mkdir-directitem1.firstdisk; cur_mkdir-directitem1.property=1; cur_mkdir-directitem1.size=ROOT_DISK_SIZE; for(i=2;idire

25、ctitemi.sign=0; cur_mkdir-directitemi.firstdisk=-1; strcpy(cur_mkdir-directitemi.name,“); cur_mkdir-directitemi.next=-1; cur_mkdir-directitemi.property=0; cur_mkdir-directitemi.size=0; return 0; int rmdir(char *name) int i,j,item; struct direct *temp_dir; /*-检查当前目录项中有无该目录-*/ for(i=2;idirectitemi.nam

26、e,name) break; if(i=MSD+2) /*-没有这个文件或目录-*/ return(-1);if(cur_dir-directitemi.property!=1)/*-删除的不是目录-*/ return(-3); /*-判断要删除的目录有无子目录-*/ temp_dir=(struct direct *)(fdisk+cur_dir-directitemi.next*DISKSIZE); for(j=2;jdirectitemj.next!=-1) break; if(jdirectitemi.firstdisk; fatitem.em_disk=0; /*-修改目录项-*/

27、cur_dir-directitemi.sign=0; cur_dir-directitemi.firstdisk=-1; strcpy(cur_dir-directitemi.name,“); cur_dir-directitemi.next=-1; cur_dir-directitemi.property=0; cur_dir-directitemi.size=0; return 0; void dir() int i; for(i=2;idirectitemi.firstdisk!=-1) /*-如果存在子目录-*/ printf(“%st“,cur_dir-directitemi.na

28、me); if(cur_dir-directitemi.property=0) /*-文件-*/ printf(“%dttn“,cur_dir-directitemi.size); else printf(“ttn“); int cd(char *name) int i,j,item; char *str; char *temp,*point,*point1; struct direct *temp_dir; temp_dir=cur_dir; str=name; if(!strcmp(“,name) cur_dir = root; strcpy(bufferdir,“Root:“); ret

29、urn 0; temp = (char *)malloc(DIR_MAXSIZE*sizeof(char);/*-最长路径名字分配空间-*/ for(i=0;idirectitemj.name,temp) break; free(temp);/*释放申请的临时空间*/ /if(temp_dir-directitemj.property!=1) /*-打开的不是目录-*/ /return(-2); if(j=MSD+2) /*-不在当前目录-*/ return(-1); item=temp_dir-directitemj.firstdisk; /*-当前目录在磁盘中位置-*/ temp_dir=

30、(struct direct *)(fdisk+item*DISKSIZE); if(!strcmp(“,name) if(cur_dir-directitemj-1.sign!=1) /*-如果上级目录不是根目录-*/ point=strchr(bufferdir,); /查找字符串bufferdir中首次出现字符 的位置while(point!=NULL) point1=point+1; /*-减去所占的空间,记录下次查找的起始地址-*/ point=strchr(point1,); *(point1-1)=0; /*-将上一级目录删除-*/ else /if(name0 !=) buff

31、erdir = strcat(bufferdir,“); /*-修改当前目录-*/ bufferdir = strcat(bufferdir,name); cur_dir=temp_dir; /*-将当前目录确定下来-*/ return 0; void show() printf(“%s“,bufferdir); void print() printf(“*n“);printf(“*文件系统设计*n“); printf(“*t命令格式 说明 *n“); printf(“*tcd 目录名 更改当前目录 *n“); printf(“*tmkdir 目录名 创建子目录 *n“); printf(“*

32、trmdir 目录名 删除子目录 *n“); printf(“*tdir 显示当前目录的子目录 *n“); printf(“*tcreate 文件名 创建文件 *n“); printf(“*tdel 文件名 删除文件 *n“); printf(“*topen 文件名 打开文件 *n“); printf(“*tclose 文件名 关闭文件 *n“); printf(“*tread 读文件 *n“); printf(“*twrite 写文件 *n“); printf(“*texit 退出系统 *n“); printf(“*n“); void main() FILE *fp; char ch; ch

33、ar a100; char code1110; char name10; int i,flag,r_size; char *contect; contect = (char *)malloc(MAX_WRITE*sizeof(char); if(fp=fopen(“disk.dat“,“rb“)=NULL) printf(“You have not format,Do you want format?(y/n)“); scanf(“%c“, if(ch=y) initfile(); printf(“Successfully format! n“); else return; enter();p

34、rint(); show(); strcpy(code0,“exit“); strcpy(code1,“create“); strcpy(code2,“open“); strcpy(code3,“close“); strcpy(code4,“write“); strcpy(code5,“read“); strcpy(code6,“del“); strcpy(code7,“mkdir“); strcpy(code8,“rmdir“); strcpy(code9,“dir“); strcpy(code10,“cd“); while(1) scanf(“%s“,a); for(i=0;i11;i+)

35、 if(!strcmp(codei,a) break; switch(i) case 0: /退出文件系统free(contect); halt(); return; case 1: /创建文件scanf(“%s“,name); flag = create(name); if(flag=-1) printf(“Error: n The length is too long !n“); else if(flag=-2) printf(“Error: n The direct item is already full !n“); else if(flag=-3) printf(“Error: n

36、The number of openfile is too much !n“); else if(flag=-4) printf(“Error: n The name is already in the direct !n“); else if(flag=-5) printf(“Error: n The disk space is full!n“); else printf(“Successfully create a file! n“); show(); break; case 2:/打开文件scanf(“%s“,name); fd = open(name); if(fd = -1) pri

37、ntf(“Error: n The open file not exit! n“); else if(fd = -2) printf(“Error: n The file have already opened! n“); else if(fd = -3) printf(“Error: n The number of open file is too much! n“); else if(fd = -4) printf(“Error: n It is a direct,can not open for read or write! n“); else printf(“Successfully

38、opened! n“); show(); break; case 3:/关闭文件 scanf(“%s“,name); flag = close(name); if(flag = -1) printf(“Error:n The file is not opened ! n“); else printf(“Successfully closed! n“); show(); break; case 4:/写文件if(fd =-1) printf(“Error:n The file is not opened ! n“); else printf(“Please input the file contect:“); scanf(“%s“,contect); flag=write(fd,contect,strlen(contect); if(flag = 0) printf(“Successfully write! n“); else printf(“Error:n The disk size is not enough! n“); show(); break; case 5:/读文件if(fd =-1) printf(“Error:n The file is not opened ! n“); else