操作系统课程设计报告1

1、操作系统课程设计报告专 业：学 号：姓 名：任艺锦提交日期：2012年1月5日【设计目的】（1）本实验的目的是通过一个简单多用户文件系统的设计，加深理解文件系统的内部功能和内部实现。（2）结合数据结构、程序设计、计算机原理等课程的知识，设计一个二级文件系统，进一步理解操作系统。（3）通过分对实际问题的分析、设计、编程实现，提高实际应用、编程的能力【设计内容】1. 理解二级目录的文件系统的组织；2. 掌握常用的数据结构；3. 为linux系统设计一个简单的二级文件系统。其中第一级对应于用户账号，第二级对应于用户帐号下的文件；使用文件来模拟外存，进行数据结构设计和操作算法的设计，实现一个文件系统并

2、实现基本的文件操作（为了简便文件系统，暂不考虑文件共享，文件系统安全以及管道文件与设备文件等特殊内容）。要求做到以下几点：可以实现下列几条命令： login 用户登录dir 列目录create 创建文件delete 删除文件open 打开文件close 关闭文件write 写文件read 读文件cd 进出目录列目录时要列出文件名，物理地址，保护码和文件长度；源文件可以进行读写保护。【实验环境】windows xp操作系统microsoft visual c+ 6.0【相关知识综述】本实验设计的文件系统采用两级目录，其中第一级对应于用户账号，第二级对应于用户帐号下的文件。为了简便文件系统暂未考虑

3、文件共享，文件系统安全以及管道文件与设备文件等特殊内容。首先应确定文件系统的数据结构：主目录、子目录及活动文件等。主目录和子目录都以文件的形式存放于磁盘，这样便于查找和修改。用户创建的文件，可以编号存储于磁盘上。如：file0,file1,file2并以编号作为物理地址，在目录中进行登记。【设计思路】主要数据结构：#define maxname 25 /*the largest length of mfdname,ufdname,filename*/#define maxchild 50 /*the largest child*/#define max (maxchild*maxchild)

4、/*the size of fpaddrno*/typedef struct /*the structure of osfile*/ int fpaddr; /*file physical address*/ int flength; /*file length*/ int fmode; /*file mode:0-read only;1-write only;2-read and write(default);*/ char fnamemaxname; /*file name*/ osfile;typedef struct /*the structure of osufd*/ char uf

5、dnamemaxname; /*ufd name*/ osfile ufdfilemaxchild; /*ufd own file*/ osufd;typedef struct /*the structure of osufdlogin*/ char ufdnamemaxname; /*ufd name*/ char ufdpword8; /*ufd password*/ osufd_login;typedef struct /*file open mode*/ nt ifopen; /*ifopen:0-close,1-open*/ int openmode; /*0-read only,1

6、-write only,2-read and write,3-initial*/ osufd_openmode;主要函数： void loginf(); /*login filesystem*/ void dirf(); /*dir filesystem*/ void cdf(); /*change dir*/ void createf(); /*create file*/ void deletef(); /*delete file*/ void modifyfm(); /*modify filemode*/ void openf(); /*open file*/ void closef();

7、 /*close file*/ void readf(); /*read file*/ void writef(); /*write file*/ void quitf(); /*quit filesystem*/ void help();注意事项：操作后用exit命令退出，完成向ufd文件的写入程序设计的流程图见下页使用microsoft office visio 20031.程序流程图（总体）2. 删除模块3. 打开模块4. 关闭模块5. 写模块【源程序清单】1. delete删除功能void deletef() char fnamemaxname; char str50,str150;

8、int i,j,k; char a25; char *rtrim(char *str); char *ltrim(char *str); int existf(char *filename); int existd(char *dirname); printf(nplease input filename:); gets(fname); ltrim(rtrim(fname); i=existf(fname); if (i=0) k=existd(username); if(ifopenki.ifopen=1) printf(n%s has been opened. please close i

9、t before delete.n,fname); wgetchar=1; elseif(ufdk-ufdfilei.fmode=3) printf(n%s is in protect status. n,fname); wgetchar=1; else printf(%s will be deleted. are you sure？please input y or n:,fname); gets(a); ltrim(rtrim(a); if(strcmp(strupr(a),y)=0) fpaddrnoufdk-ufdfilei.fpaddr=0; for(j=i;jufdfilej.fn

10、ame,ufdk-ufdfilej+1.fname); ufdk-ufdfilej.fpaddr=ufdk-ufdfilej+1.fpaddr; ufdk-ufdfilej.flength=ufdk-ufdfilej+1.flength; ufdk-ufdfilej.fmode=ufdk-ufdfilej+1.fmode; ifopenkj=ifopenkj+1; remove(str1); fcountk-; printf(n%s has been deleted successfully.n,fname); wgetchar=1; else if(strcmp(strupr(a),n)=0

11、) printf(n%s hasnt been deleted.n,fname); wgetchar=1; else printf(n%s doesnt exist.n,fname);wgetchar=1;2. open打开功能void openf() /*open file*/char fnamemaxname; char str25,str125,fmode25; int i,k; char *rtrim(char *str); char *ltrim(char *str); int existf(char *filename); int existd(char *dirname); pr

12、intf(n please input filename:); gets(fname); ltrim(rtrim(fname); i=existf(fname); if (i=0) k=existd(dirname); if(!ifopenki.ifopen) if (ufdk-ufdfilei.fmode=3) printf(nerror. the files mode is protected. you cant open it.n);wgetchar=1; elseprintf(please input fileopenmode(0-read only,1-write only,2-re

13、ad and write):); gets(fmode); ; ltrim(rtrim(fmode); ;if(strcmp(fmode,0)=0)|(strcmp(fmode,1)=0)|(strcmp(fmode,2)=0)if(fmode0=0) ;strcpy(str,read only); if(ufdk-ufdfilei.fmode=0)|(ufdk-ufdfilei.fmode=2) ifopenki.ifopen=1; else if(fmode0=1) strcpy(str,write only); if(ufdk-ufdfilei.fmode=1)|(ufdk-ufdfil

14、ei.fmode=2) ifopenki.ifopen=1; else if(fmode0=2) strcpy(str,read and write); if(ufdk-ufdfilei.fmode=2) ifopenki.ifopen=1; if(ufdk-ufdfilei.fmode=0) strcpy(str1,read only); else if(ufdk-ufdfilei.fmode=1) strcpy(str1,write only); else if(ufdk-ufdfilei.fmode=2) strcpy(str1,read and write); if(ifopenki.

15、ifopen=1) ifopenki.openmode=atoi(fmode); if (ifopenki.openmode=0) strcpy(str,read only); else if(ifopenki.openmode=1) strcpy(str,write only); else if(ifopenki.openmode=2) strcpy(str,read and write); printf(n%s has been opened. openmode is %s,filemode is %sn,fname,strupr(str),strupr(str1); wgetchar=1

16、; else printf(nerror. %s hasnt been opened. openmode error. openmode is %s,but filemode is %sn,fname,strupr(str),strupr(str1); wgetchar=1; elseprintf(nerror. %s please input fileopenmode range between 0 and 2.n,fname); wgetchar=1; elseprintf(nerror. %s is in open status.n,fname);wgetchar=1; else pri

17、ntf(nerror. %s does not exist.n,fname); wgetchar=1; 3. close关闭功能void closef() /*close file*/int i,k,n=0; char fnamemaxname; char *rtrim(char *str); char *ltrim(char *str); int existf(char *filename); int existd(char *dirname); k=existd(dirname); printf(nopen files in the ufd:n); for(i=0;iufdfilei.fn

18、ame); n+; if(n%5=0)&(n!=0) printf(n); while(n!=0) printf(n please input filename that you want to close:); gets(fname); ltrim(rtrim(fname); i=existf(fname); if(i=0) if(ifopenki.ifopen=1) ifopenki.ifopen=0; printf(n%s has been closed successfully.n,fname); wgetchar=1; else printf(nerror.%s is in clos

19、ing status.n,fname); wgetchar=1; else printf(nerror. %s is not exist.n,fname); wgetchar=1; break; while (n=0)printf(n there are no file in open status.); wgetchar=1;break;4. write写功能void writef() /*write file*/int i,k,n=0,length;char fnamemaxname;char str255,str1255;char *rtrim(char *str); char *ltr

20、im(char *str); int existf(char *filename); int existd(char *dirname);printf(opened files list:n); k=existd(dirname); for(i=0;iufdfilei.fname); n+;if(n%5=0)&(n!=0)printf(n); printf(n%d files openned.n,n); if(n=0) wgetchar=1; if(n!=0) printf(nplease input filename:); gets(fname); ltrim(rtrim(fname); i

21、=existf(fname); if(i=0) if(ifopenki.ifopen=1)if(ifopenki.openmode=1) |(ifopenki.openmode=2) itoa(ufdk-ufdfilei.fpaddr,str,10);strcpy(str1,file); strcat(str1,str); strcpy(str,c:osfilefile);strcat(str,str1); strcat(str,.txt); fp_file=fopen(str,ab);length=writef1(); ufdk-ufdfilei.flength=ufdk-ufdfilei.flength+length; printf(nn%d length.n,ufdk-ufdfilei.flength); printf(nthe file has been write successfully!);fclose(fp_file);else if(ifopenki.openmode=0) printf(nerror.%s has been opened with read only mode. it isnt write