access.c

操作系统简单的登入程序

#include <stdio.h>
#include "filesys.h"


unsigned int access(user_id,inode1,mode)
unsigned short user_id;
struct inode* inode1;
unsigned short mode;
{
	switch(mode)
		{
		case READ:
			if(inode1->di_mode&ODIREAD) return 1;
			if((inode1->di_mode&GDIREAD)&&(strcmp(directory_1.users[user_id].u_gid,inode1->di_gid)==0)) return 1;
			if((inode1->di_mode&UDIREAD)&&(strcmp(directory_1.users[user_id].u_uid,inode1->di_uid)==0)) return 1;
			return 0;
		case WRITE:
			if(inode1->di_mode&ODIWRITE) return 1;
			if((inode1->di_mode&GDIWRITE)&&(strcmp(directory_1.users[user_id].u_gid,inode1->di_gid)==0 )) return 1;
			if((inode1->di_mode&UDIWRIRE)&&(strcmp(directory_1.users[user_id].u_uid,inode1->di_uid)==0)) return 1;
			return 0;
		case EXECUTE:		
			if(inode1->di_mode&ODIEXECUTE) return 1;
			if((inode1->di_mode&GDIEXECUTE)&&(strcmp(directory_1.users[user_id].u_gid, inode1->di_gid )==0)) return 1;
			if((inode1->di_mode&UDIEXECUTE)&&(strcmp(directory_1.users[user_id].u_uid,inode1->di_uid)==0)) return 1;
			return 0;
		defalut:
				return 0;
		}	
}