In this workshop you will be implementing a file system simulator, loosely based on the historic file system used

by the CP$/$M system.

The file system will be have the following properties:

$$ it is a single level directory system.

$$ the directory entry has the following format:

struct entry

$\{$

int$8\_$t user;

char name$[9]$;

char extension$[4]$;

int$16\_$t blockcount;

int$16\_$t block$[24]$;

$\}$;

With the name and extension fields being C style strings. This structure is $64$ bytes in size.

$$ The disk size is $851$ kbyte. $($This is the $5$

$1$

$4$

$$ inch disk used by the Apple Lisa.$)$

$$ The smallest unit of allocation is $512$ bytes.

$$ There are $16$ files on the disk, so the directory takes up the first $2$ blocks on the disk.

$$ No control information about it needs to be stored in the directory $($i$.$e$.$ no $.$ entry$).$

$$ The only user is user $1$

$$ User $1$ is not a valid user, and could be used to mark free directory entries.

$$ Alongside the directory you also need a bitmap that is capable of representing all of the blocks available

on the disk, this can be a free space bitmap or an allocation bitmap, this is your choice. This structure is

not stored on the disk but would be computed by the operating system when the disk was inserted. Your

bitmap will need to track the directory blocks, so they are not allocated to another file.

You are not supposed to implement the actual storage, only the control structures of the file system. When

implementing the free bitmap you must use a bitmap, i$.$e$.$ it should be an array, but each element of the array

should represent several blocks.