Add listing to EXT2
diff --git a/include/kernel/dri/fs/ext2/ext2.h b/include/kernel/dri/fs/ext2/ext2.h
index 4205c4b..0ffeaac 100644
--- a/include/kernel/dri/fs/ext2/ext2.h
+++ b/include/kernel/dri/fs/ext2/ext2.h
@@ -4,55 +4,79 @@
 
 struct ext2_superblock
 {
-	// Total number of inodes
+	/// Total number of inodes
 	uint total_inodes;
-	// Total number of blocks
+
+	/// Total number of blocks
 	uint total_blocks;
-	// Number of blocks reserved for superuser
+
+	/// Number of blocks reserved for superuser
 	uint blocks_reserved_for_superuser;
-	// Number of unallocated blocks
+
+	/// Number of unallocated blocks
 	uint unallocated_blocks;
-	// Number of unallocated inodes
+
+	/// Number of unallocated inodes
 	uint unallocated_inodes;
-	// Block number containing the superblock
+
+	/// Block number containing the superblock
 	uint superblock_block_number;
-	// the number to shift 1024 to the left by to get the block size
+
+	/// the number to shift 1024 to the left by to get the block size
 	uint block_size_shift;
-	// the number to shift 1024 to the left by to get the fragment size
+
+	/// the number to shift 1024 to the left by to get the fragment size
 	uint fragment_size_shift;
-	// Number of blocks in one block group
+
+	/// Number of blocks in one block group
 	uint blocks_per_block_group;
-	// Number of fragments in one block group
+
+	/// Number of fragments in one block group
 	uint fragments_per_block_group;
-	// Number of inodse in one block group
+
+	/// Number of inodse in one block group
 	uint inodes_per_block_group;
-	// UNIX time of last mount
+
+	/// UNIX time of last mount
 	uint last_mount_time;
-	// UNIX time of last write
+
+	/// UNIX time of last write
 	uint last_write_time;
-	// Number of mounts since last consistency check
+
+	/// Number of mounts since last consistency check
 	ushort mounts_since_last_fsck;
-	// Number of mounts allowed between consistency checks
+
+	/// Number of mounts allowed between consistency checks
 	ushort mounts_allowed_before_fsck;
-	// EXT2 signature, should be 0xef53
+
+	/// EXT2 signature, should be 0xef53
 	ushort signature;
-	// File system state, see enum ext2_fs_state
+
+	/// File system state, see enum ext2_fs_state
 	ushort state;
-	// What to do in case of an error, see enum ext2_error_case
+
+	/// What to do in case of an error, see enum ext2_error_case
 	ushort error_case;
-	// Minor portion of version
+
+	/// Minor portion of version
 	ushort version_minor;
-	// UNIX time of last consistency check
+
+	/// UNIX time of last consistency check
 	uint last_fsck_time;
-	// Max time between consistency checks
+
+	/// Max time between consistency checks
 	uint fsck_time_interval;
-	// Operating system ID of creator
+
+	/// Operating system ID of creator
 	uint creator_os_id;
-	// Major portion of version
+
+	/// Major portion of version
 	uint version_major;
-	// User ID that can use reserved blocks
+
+	/// User ID that can use reserved blocks
 	ushort reserved_blocks_uid;
-	// Group ID that can use reserved blocks
+
+	/// Group ID that can use reserved blocks
 	ushort reserved_blocks_gid;
 };
 
@@ -80,6 +104,177 @@
 
 #define EXT2_SIGNATURE 0xef53
 
+struct ext2_block_group_descriptor
+{
+	/// Address of block usage bitmap
+	uint block_bitmap;                           // 4
+
+	/// Address of inode usage bitmap
+	uint inode_bitmap;                           // 8
+
+	/// Starting block address of inode table
+	uint inode_table_start_block;                // 12
+
+	/// Number of unallocated blocks in this group
+	ushort unallocated_blocks;                   // 14
+
+	/// Number of unallocated inodes in this group
+	ushort unallocated_inodes;                   // 16
+
+	/// Number of directories in this group
+	ushort num_dirs;                             // 18
+
+	ushort padding;
+
+	uchar reserved[12];                          // 32
+};
+
+struct ext2_inode
+{
+	/// The format and permissions of the file, see EXT2_S_*
+	ushort mode;
+	
+	/// The user id of the owner
+	ushort uid;
+
+	/// The lower 32 bits of the file size
+	uint size;
+
+	/// Last time this was accessed in UNIX time
+	uint access_time;
+
+	/// Time this was created in UNIX time
+	uint created_time;
+
+	/// Time this was last modified in UNIX time
+	uint modified_time;
+
+	/// Time this was deleted in UNIX time
+	uint deleted_time;
+
+	/// Owner group id
+	ushort gid;
+
+	/// Reference count for hard links
+	ushort links_count;
+
+	/// Number of 512 byte blocks storing this files data, NOT EXT2 blocks!
+	uint num_blocks;
+
+	/// Flags describing how this file can be accessed
+	uint flags;
+
+	/// First field reserved for the operating system
+	uint os_reserved_1;
+
+	union
+	{
+		/// The blocks of this file
+		uint blocks[15];
+
+		struct
+		{
+			/// The direct blocks
+			uint direct_blocks[12];
+
+			/// The single indirect block
+			uint ind_block;
+
+			/// The double indirect block
+			uint ind2_block;
+
+			/// The triple indirect block
+			uint ind3_block;
+		};
+	};
+
+	/// Used by NFS to version files
+	uint generation;
+
+	/// File attributes, unused
+	uint file_acl;
+
+	/// Directory attributes, unused
+	uint dir_acl;
+
+	/// Location of file fragment, unused
+	uint faddr;
+
+	/// Second field reserved for the operating system
+	uchar os_reserved_2[12];
+};
+
+enum
+{
+	// File types
+	EXT2_S_IFSOCK = 0xc000,
+	EXT2_S_IFLINK = 0xa000,
+	EXT2_S_IFREG = 0x8000,
+	EXT2_S_IFBLK = 0x6000,
+	EXT2_S_IFDIR = 0x4000,
+	EXT2_S_IFCHR = 0x2000,
+	EXT2_S_IFIFO = 0x1000,
+
+	/// Set UID
+	EXT2_S_ISUID = 0x0800,
+	/// Set GUID
+	EXT2_S_ISGID = 0x0400,
+	/// Sticky
+	EXT2_S_ISVTX = 0x0200,
+
+	// Normal UNIX file permissions
+	EXT2_S_IRUSR = 0x0100,
+	EXT2_S_IWUSR = 0x0080,
+	EXT2_S_IXUSR = 0x0040,
+	EXT2_S_IRGRP = 0x0020,
+	EXT2_S_IWGRP = 0x0010,
+	EXT2_S_IXGRP = 0x0008,
+	EXT2_S_IROTH = 0x0004,
+	EXT2_S_IWOTH = 0x0002,
+	EXT2_S_IXOTH = 0x0001,
+};
+
+struct ext2_dirent
+{
+	uint inode;
+	ushort rec_len;
+	uchar name_len;
+	uchar file_type;
+	char name[];
+};
+
+/// Read a file system block (0-indexed), if necessary multiple disk blocks
+/// will be read automatically
+void ext2_read_block(struct ext2_superblock *sb, void *buffer, uint block);
+
 struct ext2_superblock ext2_read_superblock();
+
+void ext2_write_superblock(struct ext2_superblock *sb);
+
+// Just for fun, corrupt the superblock (obviously don't actually do this)
+void ext2_corrupt_superblock_for_fun();
+
 void ext2_mount(struct fs_node *where);
+
 bool ext2_valid_filesystem();
+
+bool ext2_find_inode(struct ext2_superblock *sb, uint number, struct ext2_inode *inode);
+
+/// Load a block group descriptor for a certain block group
+struct ext2_block_group_descriptor ext2_load_block_group_descriptor(
+	struct ext2_superblock *sb, uint block_group);
+
+/// List the contents of a directory dir. Calls `cb` for each item. If `dir` is
+/// not a directory, returns false. Otherwise returns true.
+bool ext2_dir_ls(struct ext2_superblock *sb,
+				 struct ext2_inode *dir,
+				 void (*cb)(uint inode,
+							const char *name,
+							void *data),
+				 void *data);
+
+/// Read a data block for the inode, 0 being the first block of the file.
+bool ext2_read_inode_block(struct ext2_superblock *sb,
+						   struct ext2_inode *inode,
+						   void *buffer,
+						   uint block);
diff --git a/include/kernel/log.h b/include/kernel/log.h
index 3365474..a4ae42b 100644
--- a/include/kernel/log.h
+++ b/include/kernel/log.h
@@ -5,6 +5,7 @@
 #define RESET "\033[0m"
 #define INFO "[\033[96m INFO  " RESET "] "
 #define OKAY "[\033[92m  OK   " RESET "] "
+#define WARN "[\033[93m WARN  " RESET "] "
 #define ERROR "[\033[91m ERROR " RESET "] "
 #define DEBUG "[\033[93m DEBUG " RESET "] "