文件系统实现.c

用vc写得操作系统课程设计题

  str1=strchr(str,'\\');
  //free(temp);
 }
 str1=str1+strlen(str);
 
 for(i=0;i<(int)strlen(str);i++)
  temp[i]=str[i];
 temp[i]='\0';

 for(j=0;j<MSD+2;j++) /*-查找该子目录是否在当前目录中-*/
 {
  if(!strcmp(temp_dir->directitem[j].name,temp))
   break;
 }

 free(temp);/*释放申请的临时空间*/
 if(temp_dir->directitem[j].property!='1') /*-打开的不是目录-*/ 
  return(-2);
 if(j>=MSD+2)  /*-不在当前目录-*/
  return(-1); 

 item=temp_dir->directitem[j].firstdisk;
 /*-当前目录在磁盘中位置-*/
 temp_dir=(struct direct *)(fdisk+item*DISKSIZE);
 
 if(!strcmp("..",name))
 {
  if(cur_dir->directitem[j-1].sign!=1) /*-如果子目录不是根目录-*/
  {
   point=strchr(bufferdir,'\\');
   while(point!=NULL)
   {
    point1=point+1; /*-减去'\'所占的空间,记录下次查找的起始地址-*/
    point=strchr(point1,'\\');
   }
   *(point1-1)='\0'; /*-将上一级目录删除-*/
  }
  else
  {
  }

 }
 else if(!strcmp(".",name))
 {
  bufferdir=bufferdir; /*-如果是当前目录则不变-*/
 }
 else
 {
  if(name[0] !='\\')
  bufferdir = strcat(bufferdir,"\\"); /*-修改当前目录-*/
  bufferdir = strcat(bufferdir,name);
 }
 cur_dir=temp_dir;  /*-将当前目录确定下来-*/
 return 0;
}


/*----------------------------------------------------------------------------------------------*/
/*---------------------------------------显示当前路径-------------------------------------------*/
void show()
{
 printf("%s>",bufferdir);
}

/*----------------------------------------------------------------------------------------------*/
/*--------------------------------------输出提示信息--------------------------------------------*/
void print()
{
 printf("********************************************************************************\n");
 printf("\t\t\tWelcome to DOS File system!\n");
 printf("--------------------------------------------------------------------------------\n");
 printf("\t\t 退出文件系统  halt\n");
 printf("\t\t 创建文件  create 文件名\n");
 printf("\t\t 删除文件  del 文件名\n");
 printf("\t\t 打开文件  open 文件名\n");
 printf("\t\t 关闭文件  close 文件名\n");
 printf("\t\t 写文件   write\n");
 printf("\t\t 读文件   read\n\n");

 printf("\t\t 创建子目录  mkdir 目录名\n");
 printf("\t\t 删除子目录  rmdir 目录名\n");
 printf("\t\t 显示当前目录的子目录 dir\n");
 printf("\t\t 更改当前目录  cd 目录名\n");
 printf("--------------------------------------------------------------------------------\n");

}

/*----------------------------------------------------------------------------------------------*/
/*------------------------------------------主函数----------------------------------------------*/
void main()
{
 FILE *fp;
 char ch;
 char a[100];
 char code[11][10];
 char name[10];
 int i,flag,r_size;
 char *contect;

 contect = (char *)malloc(MAX_WRITE*sizeof(char));
 
 if((fp=fopen("disk.dat","rb"))==NULL)/*如果还没有进行格式化，则要格式化*/
 {
  printf("You have not format,Do you want format?(y/n)");
  scanf("%c",&ch);

  if(ch=='y')
  {
   initfile();
   printf("Successfully format! \n");
  }
  else 
  {
   return;
  }
 }
  
 enter();
 print();
 show();
 /*将命令全部保存在CODE数组中*/
 strcpy(code[0],"halt");
 strcpy(code[1],"create");
 strcpy(code[2],"open");
 strcpy(code[3],"close");
 strcpy(code[4],"write");
 strcpy(code[5],"read");
 strcpy(code[6],"del");
 strcpy(code[7],"mkdir");
 strcpy(code[8],"rmdir");
 strcpy(code[9],"dir");
 strcpy(code[10],"cd");

 while(1)
 {
  scanf("%s",a);
  for(i=0;i<11;i++)
  {
   if(!strcmp(code[i],a))
    break;
  }

  switch(i)
  {
   case 0: //*--退出文件系统--//
    free(contect);
    halt();
    return;
   case 1: //*--创建文件--//
    scanf("%s",name);
    flag = create(name);
    if(flag==-1)
    {
     printf("Error: \n The length is too long !\n");
    }
    else if(flag==-2)
    {
     printf("Error: \n The direct item is already full !\n");
    }
    else if(flag==-3)
    {
     printf("Error: \n The number of openfile is too much !\n");
    }
    else if(flag==-4)
    {
     printf("Error: \n The name is already in the direct !\n");
    }
    else if(flag==-5)
    {
     printf("Error: \n The disk space is full!\n");
    }
    else
    {
     printf("Successfully create a file! \n");
    }

    show();
    break;

   case 2://--打开文件--//
    scanf("%s",name);
    fd = open(name);
    if(fd == -1)
    {
     printf("Error: \n The open file not exit! \n");
    }
    else if(fd == -2)
    {
     printf("Error: \n The file have already opened! \n");
    }
    else if(fd == -3)
    {
     printf("Error: \n The number of open file is too much! \n");
    }
    else if(fd == -4)
    {
     printf("Error: \n It is a direct,can not open for read or write! \n");
    }
    else
    {
     printf("Successfully opened! \n");
    }
    show();
    break;

   case 3://--关闭文件--//
    scanf("%s",name);
    flag = close(name);
    if(flag == -1)
    {
     printf("Error:\n The file is not opened ! \n");
    }
    else 
    {
     printf("Successfully closed! \n");
    }
    show();
    break;
  
   case 4:/*--写文件--*/
    if(fd ==-1)
    {
     printf("Error:\n The file is not opened ! \n");
    }
    else
    {
     printf("Please input the file contect:");
     scanf("%s",contect);
     flag=write(fd,contect,strlen(contect));
     if(flag == 0)
     {
      printf("Successfully write! \n");
     }
     else
     {
      printf("Error:\n The disk size is not enough! \n");
     }
    }
    show();
    break;

   case 5:/*--读文件--*/
    if(fd ==-1)
    {
     printf("Error:\n The file is not opened ! \n");
    }
    else
    {
     flag = read(fd,contect);
     if(flag == -1)
     { 
      printf("Error: \n The size is over the length of the file! \n");
     }
     else
     {
      //printf("Successfully read! \n The contect is :");
      for(i=0;i<u_opentable.openitem[fd].size;i++)
      {
       printf("%c",contect[i]);
      }
      printf("\t\n");
     }
    }
    show();
    break;

   case 6://*--删除文件--
    scanf("%s",name);
    flag = del(name);
    if(flag == -1)
    {
     printf("Error:\n The file not exit! \n");
    }
    else if(flag == -2)
    {
     printf("Error:\n The file is opened,please first close it ! \n");
    }
    else if(flag == -3)
    {
     printf("Error:\n The delete is not file ! \n");
    }
    else
    {
     printf("Successfully delete! \n");
    }
    show();
    break;
   
   case 7://*--创建子目录--/
    scanf("%s",name);
    flag = mkdir(name);
    if(flag == -1)
    {
     printf("Error:\n The length of name is to long! \n");
    }
    else if(flag == -2)
    {
     printf("Error:\n The direct item is already full ! \n");
    }
    else if(flag == -3)
    {
     printf("Error:\n The name is already in the direct ! \n");
    }
    else if(flag == -4)
    {
     printf("Error:\n \\ can not in the name of a direct ! \n");
    }
    else if(flag == -5)
    {
     printf("Error: \n The disk space is full!\n");
    }
    else if(flag == -6)
    {
     printf("Error: \n '..' or '.' can not as the name of the direct!\n");
    }
    else if(flag == 0)
    {
     printf("Successfully make dircet! \n");
    }
    show();
    break;

   case 8://*--删除子目录--/
    scanf("%s",name);
    flag = rmdir(name);
    if(flag == -1)
    {
     printf("Error:\n The direct is not exist! \n");
    }
    else if(flag == -2)
    {
     printf("Error:\nThe direct has son direct ,please first remove the son dircct!\n");
    }
    else if(flag == -3)
    {
     printf("Error:\n The remove is not direct ! \n");
    }
    else if(flag == 0)
    {
     printf("Successfully remove dircet! \n");
    }
    show();
    break;

   case 9://*--显示当前子目录--/
    dir();
    show();
    break;

   case 10:/*--更改当前目录--*/
    scanf("%s",name);
    flag = cd(name);
    if(flag == -1)
    {
     printf("Error:\n The path no correct!\n");
    }
    else if(flag == -2)
    {
     printf("Error:\nThe opened is not direct!\n");
    }
    else if(flag == -3)
    {
     printf("Error:\nThe '\\' is too much !\n"); 
    }
    show();
    break;
   
   default:
    printf("\n Error!\n The command is wrong! \n");
    show();

  }
 }
}