access.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"

unsigned int access(user_id,inode,mode)

unsigned int user_id;

struct inode *inode;

unsigned short mode;

{

   switch(mode)

   {

   case READ:

       if(inode->di_mode & ODIREAD) return 1;

      if((inode->di_mode & GDIREAD) && 

                            (user[user_id].u_gid==inode->di_gid)) return 1;   

        if((inode->di_mode & UDIREAD) && 

                            (user[user_id].u_uid==inode->di_uid)) return 1;

       return 0;

   case WRITE:

       if(inode->di_mode & ODIWRITE)  return 1;

       if((inode->di_mode & GDIWRITE)&&            

            (user[user_id].u_gid==inode->di_gid)) return 1;   

       if((inode->di_mode & UDIWRITE)&&

            (user[user_id].u_uid==inode->di_uid)) return 1;

       return 0;

   case EXICUTE:

       if(inode->di_mode & ODIEXICUTE) return 1;

       if((inode->di_mode & GDIEXICUTE)&&   

            (user[user_id].u_gid==inode->di_gid)) return 1;

       if((inode->di_mode & UDIEXICUTE)&&   

            (user[user_id].u_uid==inode->di_uid)) return 1;

       return 0;

   case DEFAULTMODE:

       return 1;

   defualt:

       return 0;

    }

 }