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diff --git a/src/structs.rs b/src/structs.rs
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+use bitflags::bitflags;
+use null_terminated::NulStr;
+use zerocopy::FromBytes;
+
+#[repr(C)]
+#[derive(Debug)]
+// https://wiki.osdev.org/Ext2
+pub struct Superblock {
+    // taken from https://wiki.osdev.org/Ext2
+    /// Total number of inodes in file system
+    pub inodes_count: u32,
+    /// Total number of blocks in file system
+    pub blocks_count: u32,
+    /// Number of blocks reserved for superuser (see offset 80)
+    pub r_blocks_count: u32,
+    /// Total number of unallocated blocks
+    pub free_blocks_count: u32,
+    /// Total number of unallocated inodes
+    pub free_inodes_count: u32,
+    /// Block number of the block containing the superblock
+    pub first_data_block: u32,
+    /// log2 (block size) - 10. (In other words, the number to shift 1,024
+    /// to the left by to obtain the block size)
+    pub log_block_size: u32,
+    /// log2 (fragment size) - 10. (In other words, the number to shift
+    /// 1,024 to the left by to obtain the fragment size)
+    pub log_frag_size: i32,
+    /// Number of blocks in each block group
+    pub blocks_per_group: u32,
+    /// Number of fragments in each block group
+    pub frags_per_group: u32,
+    /// Number of inodes in each block group
+    pub inodes_per_group: u32,
+    /// Last mount time (in POSIX time)
+    pub mtime: u32,
+    /// Last written time (in POSIX time)
+    pub wtime: u32,
+    /// Number of times the volume has been mounted since its last
+    /// consistency check (fsck)
+    pub mnt_count: u16,
+    /// Number of mounts allowed before a consistency check (fsck) must be
+    /// done
+    pub max_mnt_count: i16,
+    /// Ext2 signature (0xef53), used to help confirm the presence of Ext2
+    /// on a volume
+    pub magic: u16,
+    /// File system state (see `FS_CLEAN` and `FS_ERR`)
+    pub state: u16,
+    /// What to do when an error is detected (see `ERR_IGNORE`, `ERR_RONLY` and
+    /// `ERR_PANIC`)
+    pub errors: u16,
+    /// Minor portion of version (combine with Major portion below to
+    /// construct full version field)
+    pub rev_minor: u16,
+    /// POSIX time of last consistency check (fsck)
+    pub lastcheck: u32,
+    /// Interval (in POSIX time) between forced consistency checks (fsck)
+    pub checkinterval: u32,
+    /// Operating system ID from which the filesystem on this volume was
+    /// created
+    pub creator_os: u32,
+    /// Major portion of version (combine with Minor portion above to
+    /// construct full version field)
+    pub rev_major: u32,
+    /// User ID that can use reserved blocks
+    pub block_uid: u16,
+    /// Group ID that can use reserved blocks
+    pub block_gid: u16,
+
+    /// First non-reserved inode in file system.
+    pub first_inode: u32,
+    /// SectorSize of each inode structure in bytes.
+    pub inode_size: u16,
+    /// Block group that this superblock is part of (if backup copy)
+    pub block_group: u16,
+    /// Optional features present (features that are not required to read
+    /// or write, but usually result in a performance increase)
+    pub features_opt: u32,
+    /// Required features present (features that are required to be
+    /// supported to read or write)
+    pub features_req: u32,
+    /// Features that if not supported, the volume must be mounted
+    /// read-only)
+    pub features_ronly: u32,
+    /// File system ID (what is output by blkid)
+    pub fs_id: [u8; 16],
+    /// Volume name (C-style string: characters terminated by a 0 byte)
+    pub volume_name: [u8; 16],
+    /// Path volume was last mounted to (C-style string: characters
+    /// terminated by a 0 byte)
+    pub last_mnt_path: [u8; 64],
+    /// Compression algorithms used (see Required features above)
+    pub compression: u32,
+    /// Number of blocks to preallocate for files
+    pub prealloc_blocks_files: u8,
+    /// Number of blocks to preallocate for directories
+    pub prealloc_blocks_dirs: u8,
+    #[doc(hidden)]
+    _unused: [u8; 2],
+    /// Journal ID (same style as the File system ID above)
+    pub journal_id: [u8; 16],
+    /// Journal inode
+    pub journal_inode: u32,
+    /// Journal device
+    pub journal_dev: u32,
+    /// Head of orphan inode list
+    pub journal_orphan_head: u32,
+}
+
+#[repr(C)]
+#[derive(Debug)]
+pub struct BlockGroupDescriptor {
+    /// Block address of block usage bitmap
+    pub block_usage_addr: u32,
+    /// Block address of inode usage bitmap
+    pub inode_usage_addr: u32,
+    /// Starting block address of inode table
+    pub inode_table_block: u32,
+    /// Number of unallocated blocks in group
+    pub free_blocks_count: u16,
+    /// Number of unallocated inodes in group
+    pub free_inodes_count: u16,
+    /// Number of directories in group
+    pub dirs_count: u16,
+
+    _reserved: [u8; 14],
+}
+
+#[repr(C)]
+#[derive(Debug)]
+pub struct Inode {
+    /// Type and Permissions (see below)
+    pub type_perm: TypePerm,
+    /// User ID
+    pub uid: u16,
+    /// Lower 32 bits of size in bytes
+    pub size_low: u32,
+    /// Last Access Time (in POSIX time)
+    pub atime: u32,
+    /// Creation Time (in POSIX time)
+    pub ctime: u32,
+    /// Last Modification time (in POSIX time)
+    pub mtime: u32,
+    /// Deletion time (in POSIX time)
+    pub dtime: u32,
+    /// Group ID
+    pub gid: u16,
+    /// Count of hard links (directory entries) to this inode. When this
+    /// reaches 0, the data blocks are marked as unallocated.
+    pub hard_links: u16,
+    /// Count of disk sectors (not Ext2 blocks) in use by this inode, not
+    /// counting the actual inode structure nor directory entries linking
+    /// to the inode.
+    pub sectors_count: u32,
+    /// Flags
+    pub flags: u32,
+    /// Operating System Specific value #1
+    pub _os_specific_1: [u8; 4],
+    /// Direct block pointers
+    pub direct_pointer: [u32; 12],
+    /// Singly Indirect Block Pointer (Points to a block that is a list of
+    /// block pointers to data)
+    pub indirect_pointer: u32,
+    /// Doubly Indirect Block Pointer (Points to a block that is a list of
+    /// block pointers to Singly Indirect Blocks)
+    pub doubly_indirect: u32,
+    /// Triply Indirect Block Pointer (Points to a block that is a list of
+    /// block pointers to Doubly Indirect Blocks)
+    pub triply_indirect: u32,
+    /// Generation number (Primarily used for NFS)
+    pub gen_number: u32,
+    /// In Ext2 version 0, this field is reserved. In version >= 1,
+    /// Extended attribute block (File ACL).
+    pub ext_attribute_block: u32,
+    /// In Ext2 version 0, this field is reserved. In version >= 1, Upper
+    /// 32 bits of file size (if feature bit set) if it's a file,
+    /// Directory ACL if it's a directory
+    pub size_high: u32,
+    /// Block address of fragment
+    pub frag_block_addr: u32,
+    /// Operating System Specific Value #2
+    pub _os_specific_2: [u8; 12],
+}
+
+#[repr(C)]
+#[derive(Debug)]
+pub struct DirectoryEntry {
+    /// Inode
+    pub inode: u32,
+    /// Total size of this entry (Including all subfields)
+    pub entry_size: u16,
+    /// Name Length least-significant 8 bits
+    pub name_length: u8,
+    /// Type indicator (only if the feature bit for "directory entries have file type byte" is set, else this is the most-significant 8 bits of the Name Length)
+    pub type_indicator: TypeIndicator,
+
+    pub name: NulStr,
+}
+
+#[derive(Debug)]
+pub enum TypeIndicator {
+    Unknown,
+    Regular,
+    Directory,
+    Character,
+    Block,
+    Fifo,
+    Socket,
+    Symlink,
+}
+
+bitflags! {
+    pub struct TypePerm: u16 {
+        /// FIFO
+        const FIFO = 0x1000;
+        /// Character device
+        const CHAR_DEVICE = 0x2000;
+        /// Directory
+        const DIRECTORY = 0x4000;
+        /// Block device
+        const BLOCK_DEVICE = 0x6000;
+        /// Regular file
+        const FILE = 0x8000;
+        /// Symbolic link
+        const SYMLINK = 0xA000;
+        /// Unix socket
+        const SOCKET = 0xC000;
+        /// Other—execute permission
+        const O_EXEC = 0x001;
+        /// Other—write permission
+        const O_WRITE = 0x002;
+        /// Other—read permission
+        const O_READ = 0x004;
+        /// Group—execute permission
+        const G_EXEC = 0x008;
+        /// Group—write permission
+        const G_WRITE = 0x010;
+        /// Group—read permission
+        const G_READ = 0x020;
+        /// User—execute permission
+        const U_EXEC = 0x040;
+        /// User—write permission
+        const U_WRITE = 0x080;
+        /// User—read permission
+        const U_READ = 0x100;
+        /// Sticky Bit
+        const STICKY = 0x200;
+        /// Set group ID
+        const SET_GID = 0x400;
+        /// Set user ID
+        const SET_UID = 0x800;
+    }
+}