ext2.h

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#define EXT3_MOUNT_CHECK		0x0001	/* Do mount-time checks */
#define EXT3_MOUNT_GRPID		0x0004	/* Create files with directory's group */
#define EXT3_MOUNT_DEBUG		0x0008	/* Some debugging messages */
#define EXT3_MOUNT_ERRORS_CONT		0x0010	/* Continue on errors */
#define EXT3_MOUNT_ERRORS_RO		0x0020	/* Remount fs ro on errors */
#define EXT3_MOUNT_ERRORS_PANIC		0x0040	/* Panic on errors */
#define EXT3_MOUNT_MINIX_DF		0x0080	/* Mimics the Minix statfs */
#define EXT3_MOUNT_NOLOAD		0x0100	/* Don't use existing journal*/
#define EXT3_MOUNT_ABORT		0x0200	/* Fatal error detected */
#define EXT3_MOUNT_DATA_FLAGS		0x0C00	/* Mode for data writes: */
  #define EXT3_MOUNT_JOURNAL_DATA	0x0400	/* Write data to journal */
  #define EXT3_MOUNT_ORDERED_DATA	0x0800	/* Flush data before commit */
  #define EXT3_MOUNT_WRITEBACK_DATA	0x0C00	/* No data ordering */
#define EXT3_MOUNT_UPDATE_JOURNAL	0x1000	/* Update the journal format */
#define EXT3_MOUNT_NO_UID32		0x2000  /* Disable 32-bit UIDs */

/* Compatibility, for having both ext2_fs.h and ext3_fs.h included at once */
#ifndef _LINUX_EXT2_FS_H
#define clear_opt(o, opt)		o &= ~EXT3_MOUNT_##opt
#define set_opt(o, opt)			o |= EXT3_MOUNT_##opt
#define test_opt(sb, opt)		((sb)->u.ext3_sb.s_mount_opt & \
					 EXT3_MOUNT_##opt)
#else
#define EXT2_MOUNT_NOLOAD		EXT3_MOUNT_NOLOAD
#define EXT2_MOUNT_ABORT		EXT3_MOUNT_ABORT
#endif

#define ext3_set_bit			ext2_set_bit
#define ext3_clear_bit			ext2_clear_bit
#define ext3_test_bit			ext2_test_bit
#define ext3_find_first_zero_bit	ext2_find_first_zero_bit
#define ext3_find_next_zero_bit		ext2_find_next_zero_bit

/*
 * Maximal mount counts between two filesystem checks
 */
#define EXT3_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */
#define EXT3_DFL_CHECKINTERVAL		0	/* Don't use interval check */

/*
 * Behaviour when detecting errors
 */
#define EXT3_ERRORS_CONTINUE		1	/* Continue execution */
#define EXT3_ERRORS_RO			2	/* Remount fs read-only */
#define EXT3_ERRORS_PANIC		3	/* Panic */
#define EXT3_ERRORS_DEFAULT		EXT3_ERRORS_CONTINUE

/*
 * Structure of the super block
 */
struct ext3_super_block {
/*00*/	ULONG	s_inodes_count;		/* Inodes count */
	ULONG	s_blocks_count;		/* Blocks count */
	ULONG	s_r_blocks_count;	/* Reserved blocks count */
	ULONG	s_free_blocks_count;	/* Free blocks count */
/*10*/	ULONG	s_free_inodes_count;	/* Free inodes count */
	ULONG	s_first_data_block;	/* First Data Block */
	ULONG	s_log_block_size;	/* Block size */
	LONG	s_log_frag_size;	/* Fragment size */
/*20*/	ULONG	s_blocks_per_group;	/* # Blocks per group */
	ULONG	s_frags_per_group;	/* # Fragments per group */
	ULONG	s_inodes_per_group;	/* # Inodes per group */
	ULONG	s_mtime;		/* Mount time */
/*30*/	ULONG	s_wtime;		/* Write time */
	USHORT	s_mnt_count;		/* Mount count */
	SHORT	s_max_mnt_count;	/* Maximal mount count */
	USHORT	s_magic;		/* Magic signature */
	USHORT	s_state;		/* File system state */
	USHORT	s_errors;		/* Behaviour when detecting errors */
	USHORT	s_minor_rev_level;	/* minor revision level */
/*40*/	ULONG	s_lastcheck;		/* time of last check */
	ULONG	s_checkinterval;	/* max. time between checks */
	ULONG	s_creator_os;		/* OS */
	ULONG	s_rev_level;		/* Revision level */
/*50*/	USHORT	s_def_resuid;		/* Default uid for reserved blocks */
	USHORT	s_def_resgid;		/* Default gid for reserved blocks */
	/*
	 * These fields are for EXT3_DYNAMIC_REV superblocks only.
	 *
	 * Note: the difference between the compatible feature set and
	 * the incompatible feature set is that if there is a bit set
	 * in the incompatible feature set that the kernel doesn't
	 * know about, it should refuse to mount the filesystem.
	 *
	 * e2fsck's requirements are more strict; if it doesn't know
	 * about a feature in either the compatible or incompatible
	 * feature set, it must abort and not try to meddle with
	 * things it doesn't understand...
	 */
	ULONG	s_first_ino;		/* First non-reserved inode */
	USHORT   s_inode_size;		/* size of inode structure */
	USHORT	s_block_group_nr;	/* block group # of this superblock */
	ULONG	s_feature_compat;	/* compatible feature set */
/*60*/	ULONG	s_feature_incompat;	/* incompatible feature set */
	ULONG	s_feature_ro_compat;	/* readonly-compatible feature set */
/*68*/	UCHAR	s_uuid[16];		/* 128-bit uuid for volume */
/*78*/	char	s_volume_name[16];	/* volume name */
/*88*/	char	s_last_mounted[64];	/* directory where last mounted */
/*C8*/	ULONG	s_algorithm_usage_bitmap; /* For compression */
	/*
	 * Performance hints.  Directory preallocation should only
	 * happen if the EXT3_FEATURE_COMPAT_DIR_PREALLOC flag is on.
	 */
	UCHAR	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
	UCHAR	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
	USHORT	s_padding1;
	/*
	 * Journaling support valid if EXT3_FEATURE_COMPAT_HAS_JOURNAL set.
	 */
/*D0*/	UCHAR	s_journal_uuid[16];	/* uuid of journal superblock */
/*E0*/	ULONG	s_journal_inum;		/* inode number of journal file */
	ULONG	s_journal_dev;		/* device number of journal file */
	ULONG	s_last_orphan;		/* start of list of inodes to delete */

/*EC*/	ULONG	s_reserved[197];	/* Padding to the end of the block */
};

#ifdef __KERNEL__
#define EXT3_SB(sb)	(&((sb)->u.ext3_sb))
#define EXT3_I(inode)	(&((inode)->u.ext3_i))
#else
/* Assume that user mode programs are passing in an ext3fs superblock, not
 * a kernel struct super_block.  This will allow us to call the feature-test
 * macros from user land. */
#define EXT3_SB(sb)	(sb)
#endif

#define NEXT_ORPHAN(inode) (inode)->u.ext3_i.i_dtime

/*
 * Codes for operating systems
 */
#define EXT3_OS_LINUX		0
#define EXT3_OS_HURD		1
#define EXT3_OS_MASIX		2
#define EXT3_OS_FREEBSD		3
#define EXT3_OS_LITES		4

/*
 * Revision levels
 */
#define EXT3_GOOD_OLD_REV	0	/* The good old (original) format */
#define EXT3_DYNAMIC_REV	1	/* V2 format w/ dynamic inode sizes */

#define EXT3_CURRENT_REV	EXT3_GOOD_OLD_REV
#define EXT3_MAX_SUPP_REV	EXT3_DYNAMIC_REV

#define EXT3_GOOD_OLD_INODE_SIZE 128

/*
 * Feature set definitions
 */

#define EXT3_HAS_COMPAT_FEATURE(sb,mask)			\
	( EXT3_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask) )
#define EXT3_HAS_RO_COMPAT_FEATURE(sb,mask)			\
	( EXT3_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask) )
#define EXT3_HAS_INCOMPAT_FEATURE(sb,mask)			\
	( EXT3_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask) )
#define EXT3_SET_COMPAT_FEATURE(sb,mask)			\
	EXT3_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
#define EXT3_SET_RO_COMPAT_FEATURE(sb,mask)			\
	EXT3_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
#define EXT3_SET_INCOMPAT_FEATURE(sb,mask)			\
	EXT3_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
#define EXT3_CLEAR_COMPAT_FEATURE(sb,mask)			\
	EXT3_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
#define EXT3_CLEAR_RO_COMPAT_FEATURE(sb,mask)			\
	EXT3_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
#define EXT3_CLEAR_INCOMPAT_FEATURE(sb,mask)			\
	EXT3_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)

#define EXT3_FEATURE_COMPAT_DIR_PREALLOC	0x0001
#define EXT3_FEATURE_COMPAT_IMAGIC_INODES	0x0002
#define EXT3_FEATURE_COMPAT_HAS_JOURNAL		0x0004
#define EXT3_FEATURE_COMPAT_EXT_ATTR		0x0008
#define EXT3_FEATURE_COMPAT_RESIZE_INODE	0x0010
#define EXT3_FEATURE_COMPAT_DIR_INDEX		0x0020

#define EXT3_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
#define EXT3_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
#define EXT3_FEATURE_RO_COMPAT_BTREE_DIR	0x0004

#define EXT3_FEATURE_INCOMPAT_COMPRESSION	0x0001
#define EXT3_FEATURE_INCOMPAT_FILETYPE		0x0002
#define EXT3_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */

#define EXT3_FEATURE_COMPAT_SUPP	0
/*#define EXT3_FEATURE_INCOMPAT_SUPP	(EXT3_FEATURE_INCOMPAT_FILETYPE| \
					 EXT3_FEATURE_INCOMPAT_RECOVER)*/
#define EXT3_FEATURE_INCOMPAT_SUPP	(EXT3_FEATURE_INCOMPAT_FILETYPE)
#define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT3_FEATURE_RO_COMPAT_SPARSE_SUPER| \
					 EXT3_FEATURE_RO_COMPAT_LARGE_FILE| \
					 EXT3_FEATURE_RO_COMPAT_BTREE_DIR)

/*
 * Default values for user and/or group using reserved blocks
 */
#define	EXT3_DEF_RESUID		0
#define	EXT3_DEF_RESGID		0

/*
 * Structure of a directory entry
 */
#define EXT3_NAME_LEN 255

struct ext3_dir_entry {
	ULONG	inode;			/* Inode number */
	USHORT	rec_len;		/* Directory entry length */
	USHORT	name_len;		/* Name length */
	CHAR	name[EXT3_NAME_LEN];	/* File name */
};

/*
 * The new version of the directory entry.  Since EXT3 structures are
 * stored in intel byte order, and the name_len field could never be
 * bigger than 255 chars, it's safe to reclaim the extra byte for the
 * file_type field.
 */
struct ext3_dir_entry_2 {
	ULONG	inode;			/* Inode number */
	USHORT	rec_len;		/* Directory entry length */
	UCHAR	name_len;		/* Name length */
	UCHAR	file_type;
	CHAR	name[EXT3_NAME_LEN];	/* File name */
};

/*
 * Ext3 directory file types.  Only the low 3 bits are used.  The
 * other bits are reserved for now.
 */
#define EXT3_FT_UNKNOWN		0
#define EXT3_FT_REG_FILE	1
#define EXT3_FT_DIR		2
#define EXT3_FT_CHRDEV		3
#define EXT3_FT_BLKDEV		4
#define EXT3_FT_FIFO		5
#define EXT3_FT_SOCK		6
#define EXT3_FT_SYMLINK		7

#define EXT3_FT_MAX		8

/*
 * EXT3_DIR_PAD defines the directory entries boundaries
 *
 * NOTE: It must be a multiple of 4
 */
#define EXT3_DIR_PAD			4
#define EXT3_DIR_ROUND			(EXT3_DIR_PAD - 1)
#define EXT3_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT3_DIR_ROUND) & \
					 ~EXT3_DIR_ROUND)

#ifdef __KERNEL__
/*
 * Describe an inode's exact location on disk and in memory
 */
struct ext3_iloc
{
	struct buffer_head *bh;
	struct ext3_inode *raw_inode;
	unsigned long block_group;
};



#endif	/* __KERNEL__ */

#endif	/* _LINUX_EXT3_FS_H */



typedef struct ext3_super_block	EXT2_SUPER_BLOCK, *PEXT2_SUPER_BLOCK;
typedef struct ext3_inode		EXT2_INODE, *PEXT2_INODE;
typedef struct ext3_group_desc	EXT2_GROUP_DESC, *PEXT2_GROUP_DESC;
typedef struct ext3_dir_entry_2	EXT2_DIR_ENTRY, *PEXT2_DIR_ENTRY;

// EXT2_INODE::i_mode values
#define EXT2_S_IRWXO	0x0007	// Other mask
#define EXT2_S_IXOTH	0x0001	// ---------x execute
#define EXT2_S_IWOTH	0x0002	// --------w- write
#define EXT2_S_IROTH	0x0004	// -------r-- read

#define EXT2_S_IRWXG	0x0038	// Group mask
#define EXT2_S_IXGRP	0x0008	// ------x--- execute
#define EXT2_S_IWGRP	0x0010	// -----w---- write
#define EXT2_S_IRGRP	0x0020	// ----r----- read

#define EXT2_S_IRWXU	0x01C0	// User mask
#define EXT2_S_IXUSR	0x0040	// ---x------ execute
#define EXT2_S_IWUSR	0x0080	// --w------- write
#define EXT2_S_IRUSR	0x0100	// -r-------- read

#define EXT2_S_ISVTX	0x0200	// Sticky bit
#define EXT2_S_ISGID	0x0400	// SGID
#define EXT2_S_ISUID	0x0800	// SUID

#define EXT2_S_IFMT		0xF000	// Format mask
#define EXT2_S_IFIFO	0x1000	// FIFO buffer
#define EXT2_S_IFCHR	0x2000	// Character device
#define EXT2_S_IFDIR	0x4000	// Directory
#define EXT2_S_IFBLK	0x6000	// Block device
#define EXT2_S_IFREG	0x8000	// Regular file
#define EXT2_S_IFLNK	0xA000	// Symbolic link
#define EXT2_S_IFSOCK	0xC000	// Socket

#define FAST_SYMLINK_MAX_NAME_SIZE	(EXT3_N_BLOCKS * sizeof(ULONG)) /* 60 bytes */

typedef struct
{
	ULONGLONG			FileSize;			// File size
	ULONGLONG			FilePointer;		// File pointer
	ULONG*		FileBlockList;		// File block list
	UCHAR			DriveNumber;		// Drive number of open file
	EXT2_INODE	Inode;				// File's inode
} EXT2_FILE_INFO, * PEXT2_FILE_INFO;



BOOLEAN	Ext2OpenVolume(UCHAR DriveNumber, ULONGLONG VolumeStartSector);
FILE*	Ext2OpenFile(PCSTR FileName);
BOOLEAN	Ext2LookupFile(PCSTR FileName, PEXT2_FILE_INFO Ext2FileInfoPointer);
BOOLEAN	Ext2SearchDirectoryBufferForFile(PVOID DirectoryBuffer, ULONG DirectorySize, PCHAR FileName, PEXT2_DIR_ENTRY DirectoryEntry);
BOOLEAN	Ext2ReadFile(FILE *FileHandle, ULONGLONG BytesToRead, ULONGLONG* BytesRead, PVOID Buffer);
ULONGLONG		Ext2GetFileSize(FILE *FileHandle);
VOID	Ext2SetFilePointer(FILE *FileHandle, ULONGLONG NewFilePointer);
ULONGLONG		Ext2GetFilePointer(FILE *FileHandle);
BOOLEAN	Ext2ReadVolumeSectors(UCHAR DriveNumber, ULONGLONG SectorNumber, ULONGLONG SectorCount, PVOID Buffer);

BOOLEAN	Ext2ReadSuperBlock(VOID);
BOOLEAN	Ext2ReadGroupDescriptors(VOID);
BOOLEAN	Ext2ReadDirectory(ULONG Inode, PVOID* DirectoryBuffer, PEXT2_INODE InodePointer);
BOOLEAN	Ext2ReadBlock(ULONG BlockNumber, PVOID Buffer);
BOOLEAN	Ext2ReadPartialBlock(ULONG BlockNumber, ULONG StartingOffset, ULONG Length, PVOID Buffer);
ULONG		Ext2GetGroupDescBlockNumber(ULONG Group);
ULONG		Ext2GetGroupDescOffsetInBlock(ULONG Group);
ULONG		Ext2GetInodeGroupNumber(ULONG Inode);
ULONG		Ext2GetInodeBlockNumber(ULONG Inode);
ULONG		Ext2GetInodeOffsetInBlock(ULONG Inode);
BOOLEAN	Ext2ReadInode(ULONG Inode, PEXT2_INODE InodeBuffer);
BOOLEAN	Ext2ReadGroupDescriptor(ULONG Group, PEXT2_GROUP_DESC GroupBuffer);
ULONG*	Ext2ReadBlockPointerList(PEXT2_INODE Inode);
ULONGLONG		Ext2GetInodeFileSize(PEXT2_INODE Inode);
BOOLEAN	Ext2CopyIndirectBlockPointers(ULONG* BlockList, ULONG* CurrentBlockInList, ULONG BlockCount, ULONG IndirectBlock);
BOOLEAN	Ext2CopyDoubleIndirectBlockPointers(ULONG* BlockList, ULONG* CurrentBlockInList, ULONG BlockCount, ULONG DoubleIndirectBlock);
BOOLEAN	Ext2CopyTripleIndirectBlockPointers(ULONG* BlockList, ULONG* CurrentBlockInList, ULONG BlockCount, ULONG TripleIndirectBlock);

#endif // #defined __EXT2_H