format.c

此版本是在网上广为流传的 二级文件系统 基础上制作的.重新编写了块操作等模块,修正了N多BUG. 实现的命令有 ls-列目录 md-创建目录 cd-进入子目录 mf-创建文件 cat-显示文件内

#include <stdio.h>
#include "filesys.h"  
format()
{
struct inode *inode;
struct direct dir_buf[BLOCKSIZ/(DIRSIZ+2)];
struct hblock hblock;
char *buf;
int i,j;

 /* creat the file system file*/
fd=fopen("filesystem","wb");/*见"谭浩强，C程序设计第二版P313"*/
buf=(char *)malloc((DINODEBLK+FILEBLK+2)*BLOCKSIZ*sizeof(char));
if(buf==NULL)
{  
    printf("\nfile system file creat failed!!!\n");
    exit(0);
}
fseek(fd,0,SEEK_SET);
fwrite(buf,1,(DINODEBLK+FILEBLK+2)*BLOCKSIZ*sizeof(char),fd);
fclose(fd);

fd=fopen("filesystem","r+b");
 
 for (i = 0; i < FILEBLK; i += NICFREE) {
     for (j = 1; j < NICFREE && i+j < FILEBLK; ++j) {
         hblock.hb_fblock[j-1] = i + j;
         hblock.hb_bmap[j-1] = 0;
     }
     hblock.hb_pblock = 0;
     hblock.hb_cur = i*BLOCKSIZ+DATASTART;
     hblock.hb_fowd = (i+NICFREE)*BLOCKSIZ+DATASTART;
     hblock.hb_back = (i-NICFREE)*BLOCKSIZ+DATASTART;
     if ( j == NICFREE )
          hblock.hb_size = NICFREE-1;
     else
          hblock.hb_size = FILEBLK%NICFREE;
     fseek(fd, DATASTART+(i*BLOCKSIZ), SEEK_SET);
     if (!fwrite(&hblock, 1, sizeof(struct hblock),fd)) printf("ERROR1");
 }
     
   /* 2.initialize the superblock */
   fseek(fd, DATASTART, SEEK_SET);
   if (!fread(&filsys.s_hblock, 1, sizeof(struct hblock), fd)) printf("ERROR2");
   
   filsys.s_isize=DINODEBLK;
   filsys.s_fsize=FILEBLK;
   filsys.s_nfree=FILEBLK-FILEBLK/NICFREE - (FILEBLK%NICFREE != 0);
   
   filsys.s_ninode=DINODEBLK*BLOCKSIZ/DINODESIZ-4;

   for(i=0;i<NICINOD;i++)
   {
   /* begin with 4,0,1,2,3,is used by main,etc,password*/
       filsys.s_inode[i]=4+i;
   }
   filsys.s_pinode=0;
   filsys.s_rinode=NICINOD+4;

/*
   for (i = 0; i < NICFREE-1; ++i) {
      printf("<%d>", filsys.s_hblock.hb_fblock[i]);
      printf("(%d)", filsys.s_hblock.hb_bmap[i]);
   }
   printf("\n");
  // getch();*/

   /*... */
   strcpy(cur_path[0], "");
   dir_lv = 1;
   
   /* 0.initialize the user */
   for(i=0;i<USERNUM;i++)
   {
       user[i].u_uid=0;
       user[i].u_gid=0;
       strcpy(user[i].u_name, "");
       strcpy(user[i].password,"");
       for(j=0;j<NOFILE;j++)
       {
       user[i].u_ofile[j]=SYSOPENFILE+1;
       }
   }
   strcpy(user[0].u_name, "root");
   strcpy(user[0].password,"root");
   user[0].u_uid=0;
   user[0].u_gid=03;
 
   /* 1. creat the main directory and its sub dir etc and the file password */
   inode=iget(0);    /* 0 empty dinode id */
   inode->di_mode=DIEMPTY;
   iput(inode);
 
   //mkdir("/");
   inode=iget(1);     /* l main dir id */
   inode->di_number=1;
   inode->di_mode=DEFAULTMODE | DIDIR;
   inode->di_size=3*(DIRSIZ+2);
   inode->di_addr[0]=balloc();    /* block 0# is used by the main directory */
   strcpy(dir_buf[0].d_name,"..");
   dir_buf[0].d_ino=1;
   strcpy(dir_buf[1].d_name,".");
   dir_buf[1].d_ino=1;
   strcpy(dir_buf[2].d_name,"etc");
   dir_buf[2].d_ino=2;
   fseek(fd,DATASTART+inode->di_addr[0]*BLOCKSIZ,SEEK_SET);
   fwrite(dir_buf,1,3*(DIRSIZ+2),fd);
   iput(inode);

   inode=iget(2);    /* 2 etc dir id */
   inode->di_number=1;
   inode->di_mode=DEFAULTMODE | DIDIR;
   inode->di_size=3*(DIRSIZ+2);
   inode->di_addr[0]=balloc();    /* block 1# is used by the etc directory*/
   strcpy(dir_buf[0].d_name,"..");
   dir_buf[0].d_ino=1;
   strcpy(dir_buf[1].d_name,".");
   dir_buf[1].d_ino=2;
   strcpy(dir_buf[2].d_name,"userinfo");
   dir_buf[2].d_ino=3;
   
   fseek(fd,DATASTART+inode->di_addr[0]*BLOCKSIZ,SEEK_SET);
   if (!fwrite(dir_buf,1,3*(DIRSIZ+2),fd)) printf("AAAAAA");
   iput(inode);
   
   inode=iget(3);    /* 3 user id */
   inode->di_number=1;
   inode->di_mode=DEFAULTMODE | DIFILE;
   inode->di_size=BLOCKSIZ;
   inode->di_addr[0]=balloc();    /* block 2# is used by the user file */
   
   fseek(fd,DATASTART+inode->di_addr[0]*BLOCKSIZ,SEEK_SET);
   if (!fwrite(user,1,BLOCKSIZ,fd)) printf("&&&&&&&");
   iput(inode);


   /* 2.initialize the superblock */
   fseek(fd,0,SEEK_SET);
   fwrite(&filsys.s_isize,1,sizeof(struct filsys),fd);
   fseek(fd,0,SEEK_SET);
   fread(&filsys.s_isize,1,sizeof(struct filsys),fd);

fclose(fd);
printf("\niget(3)---->out\n");
}