#include "head.h"
//定义全局变量
char choice;
int argc; // 用户命令的参数个数
char *argv[5]; // 用户命令的参数
int inum_cur; // 当前目录
char temp[2*BLKSIZE]; // 缓冲区
User user; // 当前的用户
char bitmap[BLKNUM]; // 位图数组
Inode inode_array[INODENUM]; // i节点数组
File_table file_array[FILENUM]; // 打开文件表数组
char image_name[10] = "data.dat"; // 文件系统名称
FILE *fp; // 打开文件指针
//创建映像hd，并将所有用户和文件清除
void format(void)
{
int i;
Inode inode;
printf("Will be to format filesystem...\n");
printf("WARNING:ALL DATA ON THIS FILESYSTEM WILL BE LOST!\n");
printf("Proceed with Format(Y/N)?");
scanf("%c", &choice);
getchar();
if((choice == 'y') || (choice == 'Y'))
{
if((fp=fopen(image_name, "w+b")) == NULL)
{
printf("Can't create file %s\n", image_name);
exit(-1);
}
for(i = 0; i < BLKSIZE; i++)
fputc('0', fp);
inode.inum = 0;
strcpy(inode.file_name, "/");
inode.type = 'd';
strcpy(inode.user_name, "/");
inode.iparent = 0;
inode.length = 0;
inode.address[0] = -1;
inode.address[1] = -1;
fwrite(&inode, sizeof(Inode), 1, fp);
inode.inum = -1;
for(i = 0; i < 31; i++)
fwrite(&inode, sizeof(Inode), 1, fp);
for(i = 0; i < BLKNUM*BLKSIZE; i++)
fputc('\0', fp);
fclose(fp);
// 打开文件user.txt
if((fp=fopen("user.txt", "w+")) == NULL)
{
printf("Can't create file %s\n", "user.txt");
exit(-1);
}
fclose(fp);
printf("Filesystem created successful.Please first login!\n");
}
return ;
}
// 功能: 用户登陆，如果是新用户则创建用户
void login(void)
{
char *p;
int flag;
char user_name[10];
char password[10];
char file_name[10] = "user.txt";
do
{
printf("login:");
gets(user_name);
printf("password:");
p=password;
while(*p=getch())
{
if(*p == 0x0d)
{
*p='\0'; //将输入的回车键转换成空格
break;
}
printf("*"); //将输入的密码以"*"号显示
p++;
}
flag = 0;
if((fp = fopen(file_name, "r+")) == NULL)
{
printf("\nCan't open file %s.\n", file_name);
printf("This filesystem not exist, it will be create!\n");
format();
login();
}
while(!feof(fp))
{
fread(&user, sizeof(User), 1, fp);
// 已经存在的用户, 且密码正确
if(!strcmp(user.user_name, user_name) &&
!strcmp(user.password, password))
{
fclose(fp);
printf("\n");
return ;
}
// 已经存在的用户, 但密码错误
else if(!strcmp(user.user_name, user_name))
{
printf("\nThis user is exist, but password is incorrect.\n");
flag = 1;
fclose(fp);
break;
}
}
if(flag == 0) break;
}while(flag);
// 创建新用户
if(flag == 0)
{
printf("\nDo you want to creat a new user?(y/n):");
scanf("%c", &choice);
gets(temp);
if((choice == 'y') || (choice == 'Y'))
{
strcpy(user.user_name, user_name);
strcpy(user.password, password);
fwrite(&user, sizeof(User), 1, fp);
fclose(fp);
return ;
}
if((choice == 'n') || (choice == 'N'))
login();
}
}
// 功能: 将所有i节点读入内存
void init(void)
{
int i;
if((fp = fopen(image_name, "r+b")) == NULL)
{
printf("Can't open file %s.\n", image_name);
exit(-1);
}
// 读入位图
for(i = 0; i < BLKNUM; i++)
bitmap[i] = fgetc(fp);
// 显示位图
// 读入i节点信息
for(i = 0; i < INODENUM; i++)
fread(&inode_array[i], sizeof(Inode), 1, fp);
// 显示i节点
// 当前目录为根目录
inum_cur = 0;
// 初始化打开文件表
for(i = 0; i < FILENUM; i++)
file_array[i].inum = -1;
}
// 功能: 分析用户命令, 将分析结果填充argc和argv
// 结果: 0-13为系统命令, 14为命令错误
int analyse(char *str)
{
int i;
char temp[20];
char *ptr_char;
char *syscmd[]={"help", "cd", "dir", "mkdir", "create", "open", "read", "write",
"close", "delet", "logout", "clear","format","quit"};
argc = 0;
for(i = 0, ptr_char = str; *ptr_char != '\0'; ptr_char++)
{
if(*ptr_char != ' ')
{
while(*ptr_char != ' ' && (*ptr_char != '\0'))
temp[i++] = *ptr_char++;
argv[argc] = (char *)malloc(i+1);
strncpy(argv[argc], temp, i);
argv[argc][i] = '\0';
argc++;
i = 0;
if(*ptr_char == '\0') break;
}
}
if(argc != 0)
{
for(i = 0; (i < 14) && strcmp(argv[0], syscmd[i]); i++);
return i;
}
else
return 14;
}
// 功能: 将num号i节点保存到hd.dat
void save_inode(int num)
{
if((fp=fopen(image_name, "r+b")) == NULL)
{
printf("Can't open file %s\n", image_name);
exit(-1);
}
fseek(fp, BLKNUM +num*sizeof(Inode), SEEK_SET);
fwrite(&inode_array[num], sizeof(Inode), 1, fp);
fclose(fp);
}
// 功能: 申请一个数据块
int get_blknum(void)
{
int i;
for(i = 0; i < BLKNUM; i++)
if(bitmap[i] == '0') break;
// 未找到空闲数据块
if(i == BLKNUM)
{
printf("Data area is full.\n");
exit(-1);
}
bitmap[i] = '1';
if((fp=fopen(image_name, "r+b")) == NULL)
{
printf("Can't open file %s\n", image_name);
exit(-1);
}
fseek(fp, i, SEEK_SET);
fputc('1', fp);
fclose(fp);
return i;
}
// 功能: 将i节点号为num的文件读入temp
void read_blk(int num)
{
int i, len;
char ch;
int add0, add1;
len = inode_array[num].length;
add0 = inode_array[num].address[0];
if(len > 512)
add1 = inode_array[num].address[1];
if((fp = fopen(image_name, "r+b")) == NULL)
{
printf("Can't open file %s.\n", image_name);
exit(-1);
}
fseek(fp, BLKSIZE+INODESIZE*INODENUM +add0*BLKSIZE, SEEK_SET);
ch = fgetc(fp);
for(i=0; (i < len) && (ch != '\0') && (i < 512); i++)
{
temp[i] = ch;
ch = fgetc(fp);
}
if(i >= 512)
{
fseek(fp,BLKSIZE+INODESIZE*INODENUM+add1*BLKSIZE, SEEK_SET);
ch = fgetc(fp);
for(; (i < len) && (ch != '\0'); i++)
{
temp[i] = ch;
ch = fgetc(fp);
}
}
temp[i] = '\0';
fclose(fp);
}
// 功能: 将temp的内容输入hd的数据区
void write_blk(int num)
{
int i, len;
int add0, add1;
add0 = inode_array[num].address[0];
len = inode_array[num].length;
if((fp = fopen(image_name, "r+b")) == NULL)
{
printf("Can't open file %s.\n", image_name);
exit(-1);
}
fseek(fp, BLKSIZE+INODESIZE*INODENUM+add0*BLKSIZE, SEEK_SET);
for(i=0; (i<len)&&(temp[i]!='\0')&&(i < 512); i++)
fputc(temp[i], fp);
if(i == 512)
{
add1 = inode_array[num].address[1];
fseek(fp, BLKSIZE+INODESIZE*INODENUM+add1*BLKSIZE, SEEK_SET);
for(; (i < len) && (temp[i] != '\0'); i++)
fputc(temp[i], fp);
}
fputc('\0', fp);
fclose(fp);
}
// 功能: 释放文件块号为num的文件占用的空间
void release_blk(int num)
{
FILE *fp;
if((fp=fopen(image_name, "r+b")) == NULL)
{
printf("Can't open file %s\n", image_name);
exit(-1);
}
bitmap[num] = '0';
fseek(fp, num, SEEK_SET);
fputc('0', fp);
fclose(fp);
}
// 功能: 显示帮助命令
void help(void)
{
printf("command: \n\
help --- show help menu \n\
clear --- clear the screen \n\
cd --- change directory \n\
mkdir --- make directory \n\
create --- create a new file \n\
open --- open a exist file \n\
read --- read a file \n\
write --- write something to a file \n\
close --- close a file \n\
delet --- delete a exist file or directory \n\
format --- format a exist filesystem \n\
logout --- exit user \n\
quit --- exit this system\n");
}
//设置文件路径
void pathset()
{
char path[50];
int m,n;
if(inode_array[inum_cur].inum == 0)
strcpy(path,user.user_name);
else
{
strcpy(path,user.user_name);
m=0;
n=inum_cur;
while(m != inum_cur)
{
while(inode_array[n].iparent != m)
{
n = inode_array[n].iparent;
}
strcat(path,"/");
strcat(path,inode_array[n].file_name);
m = n;
n = inum_cur;
}
}
printf("[%s]$",path);
}
// 功能: 切换目录(cd .. 或者 cd dir1)
void cd(void)
{
int i;
if(argc != 2)
{
printf("Command cd must have two args. \n");
return ;
}
if(!strcmp(argv[1], ".."))
inum_cur = inode_array[inum_cur].iparent;
else
{
for(i = 0; i < INODENUM; i++)
if((inode_array[i].inum>0)&&
(inode_array[i].type=='d')&&
(inode_array[i].iparent==inum_cur)&&
!strcmp(inode_array[i].file_name,argv[1])&&
!strcmp(inode_array[i].user_name,user.user_name))
break;
if(i == INODENUM)
printf("This directory isn't exsited.\n");
else
inum_cur = i;
}
}
// 功能: 显示当前目录下的子目录和文件(dir)
void dir(void)
{
int i;
int dcount=0,fcount=0;
short bcount=0;
if(argc != 1)
{
printf("Command dir must have one args. \n");
return ;
}
// 遍历i节点数组, 显示当前目录下的子目录和文件名
for(i = 0; i < INODENUM; i++)
if((inode_array[i].inum> 0) &&
(inode_array[i].iparent == inum_cur)&&
!strcmp(inode_array[i].user_name,user.user_name))
{
if(inode_array[i].type == 'd')
{
dcount++;
printf("%-20s<DIR>\n", inode_array[i].file_name);
}
else
{
fcount++;
bcount+=inode_array[i].length;
printf("%-20s%12d bytes\n", inode_array[i].file_name,inode_array[i].length);
}
}
printf("\n %d file(s)%11d bytes\n",fcount,bcount);
printf(" %d dir(s) %11d bytes FreeSpace\n",dcount,1024*1024-bcount);
}
// 功能: 在当前目录下创建子目录(mkdir dir1)
void mkdir(void)
{
int i;
if(argc != 2)
{
printf("command mkdir must have two args. \n");
return ;
}
// 遍历i节点数组, 查找未用的i节点
for(i = 0; i < INODENUM; i++)
if(inode_array[i].inum < 0) break;
if(i == INODENUM)
{
printf("Inode is full.\n");
exit(-1);
}
inode_array[i].inum = i;
strcpy(inode_array[i].file_name, argv[1]);
inode_array[i].type = 'd';
strcpy(inode_array[i].user_name,user.user_name);
inode_array[i].iparent = inum_cur;
inode_array[i].length = 0;
save_inode(i);
}
// 功能: 在当前目录下创建文件(creat file)
void create(void)
{
int i;
if(argc != 2)
{
printf("command creat must have two args. \n");
return ;
}
for(i = 0; i < INODENUM; i++)
{
if((inode_array[i].inum > 0) &&
(inode_array[i].type == 'f') &&
!strcmp(inode_array[i].file_name, argv[1]))
{
printf("This file is exsit.\n");
return ;
}
}
for(i = 0; i < INODENUM; i++)
if(inode_array[i].inum < 0) break;
if(i == INODENUM)
{
printf("Inode is full.\n");
exit(-1);
}
inode_array[i].inum = i;
strcpy(inode_array[i].file_name, argv[1]);
inode_array[i].type = 'f';
strcpy(inode_array[i].user_name, user.user_name);
inode_array[i].iparent = inum_cur;
inode_array[i].length = 0;
save_inode(i);
}
// 功能: 打开当前目录下的文件(open file1)
void open()
{
int i, inum, mode, filenum;
if(argc != 2)
{
printf("command open must have two args. \n");
return ;
}
for(i = 0; i < INODENUM; i++)
if((inode_array[i].inum > 0) &&
(inode_array[i].type == 'f') &&
!strcmp(inode_array[i].file_name,argv[1])&&
!strcmp(inode_array[i].user_name,user.user_name))
break;
if(i == INODENUM)
{
printf("The file you want to open doesn't exsited.\n");
return ;
}
inum = i;
printf("Please input open mode:(1: read, 2: write, 3: read and write):");
scanf("%d", &mode);
getchar();
if((mode < 1) || (mode > 3))
{
printf("Open mode is wrong.\n");
return;
}
for(i = 0; i < FILENUM; i++)
if(file_array[i].inum < 0) break;
if(i == FILENUM)
{
printf("The file table is full, please close some file.\n");
return ;
}
filenum = i;
file_array[filenum].inum = inum;
strcpy(file_array[filenum].file_name, inode_array[inum].file_name);
file_array[filenum].mode = mode;
printf("Open file %s by ", file_array[filenum].file_name);
if(mode == 1) printf("read only.\n");
else if(mode == 2) printf("write only.\n");
else printf("read and write.\n");
}
// 功能: 从文件中读出字符(read file1)
void read()
{
int i, inum;
if(argc != 2)
{
printf("command read must have two args. \n");
return;
}
for(i = 0; i < FILENUM; i++)
if((file_array[i].inum > 0) &&
!strcmp(file_array[i].file_name,argv[1]))
break;
if(i == FILENUM)
{
printf("Open %s first.\n", argv[1]);
return ;
}
else if(file_array[i].mode == 2)
{
printf("Can't read %s.\n", argv[1]);
return ;
}
inum = file_array[i].inum;
printf("The length of %s:%d.\n", argv[1], inode_array[inum].length);
if(inode_array[inum].length > 0)
{
read_blk(inum);
for(i = 0; (i < inode_array[inum].length) && (temp[i] != '\0'); i++)
printf("%c", temp[i]);
}
}
// 功能: 向文件中写入字符(write file1)
void write()
{
int i, inum, length;
if(argc != 2)
{
printf("Command write must have two args. \n");
return ;
}
for(i = 0; i < FILENUM; i++)
if((file_array[i].inum>0)&&
!strcmp(file_array[i].file_name,argv[1])) break;
if(i == FILENUM)
{
printf("Open %s first.\n", argv[1]);
return ;
}
else if(file_array[i].mode == 1)
{
printf("Can't write %s.\n", argv[1]);
return ;
}
inum = file_array[i].inum;
printf("The length of %s:%d\n", inode_array[inum].file_name, inode_array[inum].length);
if(inode_array[inum].length == 0)
{
i=0;
inode_array[inum].address[0] = get_blknum();
printf("Input the data(CTRL+Z to end):\n");
while(i<1023&&(temp[i]=getchar())!=EOF) i++;
temp[i]='\0';
length=strlen(temp)+1;
inode_array[inum].length=length;
if(length > 512)
inode_array[inum].address[1] = get_blknum();
save_inode(inum);
write_blk(inum);
}
else
printf("This file can't be written.\n");
}
// 功能: 关闭已经打开的文件(close file1)
void close(void)
{
int i;
if(argc != 2)
{
printf("Command close must have two args. \n");
return ;
}
for(i = 0; i < FILENUM; i++)
if((file_array[i].inum > 0) &&
!strcmp(file_array[i].file_name, argv[1])) break;
if(i == FILENUM)
{
printf("This file doesn't be opened.\n");
return ;
}
else
{
file_array[i].inum = -1;
printf("Close %s success!\n", argv[1]);
}
}
//回收i节点，有文件则删除文件
void del(int i)
{
inode_array[i].inum = -1;
if(inode_array[i].length > 0)
{
release_blk(inode_array[i].address[0]);
if(inode_array[i].length >= 512)
release_blk(inode_array[i].address[1]);
}
save_inode(i);
}
//删除子目录树和文件
void delet(void)
{
if(argc != 2)
{
printf("Command delete must have two args. \n");
return ;
}
int n,t,i;
stack<int> istk;
for(i = 0; i < INODENUM; i++)//查找待删除子目录
if((inode_array[i].inum >=0) &&
(inode_array[i].iparent == inum_cur)&&
(!strcmp(inode_array[i].file_name,argv[1]))&&
(!strcmp(inode_array[i].user_name,user.user_name)))
{
n=inode_array[i].inum;
break;
}
if(i==INODENUM) puts("Directory ERROR");
else
{
istk.push(n);
while(!istk.empty())
{
t=istk.top();
istk.pop();
del(t);
for(i = 0; i < INODENUM; i++)
if((inode_array[i].inum >=0) &&(inode_array[i].iparent == t))
istk.push(i);
}
}
}
// 功能: 退出当前用户(logout)
void logout()
{
printf("Do you want to exit this user(y/n)?");
scanf("%c", &choice);
getchar();
if((choice == 'y') || (choice == 'Y'))
{
printf("\nCurrent user has exited!\n");
login();
}
return ;
}
// 功能: 退出文件系统(quit)
void quit()
{
printf("Do you want to exist(y/n):");
scanf("%c", &choice);
getchar();
if((choice == 'y') || (choice == 'Y'))
exit(0);
}
// 功能: 显示错误
void errcmd()
{
printf("Command Error!!!\n");
}
//清空内存中存在的用户名
void free_user()
{
int i;
for(i=0;i<10;i++)
user.user_name[i]='\0';
}
// 功能: 循环执行用户输入的命令, 直到logout
// "help", "cd", "dir", "mkdir", "creat", "open","read", "write", "close", "delete", "logout", "clear", "format","quit"
void command(void)
{
char cmd[100];
system("cls");
do
{
pathset();
gets(cmd);
switch(analyse(cmd))
{
case 0:
help(); break;
case 1:
cd(); break;
case 2:
dir(); break;
case 3:
mkdir(); break;
case 4:
create(); break;
case 5:
open(); break;
case 6:
read(); break;
case 7:
write(); break;
case 8:
close(); break;
case 9:
delet(); break;
case 10:
logout();break;
case 11:
system("cls");break;
case 12:
format();
init();
free_user();
login();break;
case 13:
quit(); break;
case 14:
errcmd(); break;
default:
break;
}
}while(1);
}
// 主函数
int main(void)
{
login();
init();
command();
return 0;
}
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