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#ifndef EXT2_LIB_H
#define EXT2_LIB_H
#include <fcntl.h>
/* Definitions cribbed from ext2_fs.h, modified so's to be 64-bit clean
* when cross-compiling on Alpha
*/
/*
* The second extended filesystem constants/structures
*/
/*
* Define EXT2FS_DEBUG to produce debug messages
*/
#undef EXT2FS_DEBUG
/*
* Define EXT2FS_DEBUG_CACHE to produce cache debug messages
*/
#undef EXT2FS_DEBUG_CACHE
/*
* Define EXT2FS_CHECK_CACHE to add some checks to the name cache code
*/
#undef EXT2FS_CHECK_CACHE
/*
* Define EXT2FS_PRE_02B_COMPAT to convert ext 2 fs prior to 0.2b
*/
#undef EXT2FS_PRE_02B_COMPAT
/*
* Define DONT_USE_DCACHE to inhibit the directory cache
*/
#define DONT_USE_DCACHE
/*
* Define EXT2_PREALLOCATE to preallocate data blocks for expanding files
*/
#define EXT2_PREALLOCATE
/*
* The second extended file system version
*/
#define EXT2FS_DATE "94/03/10"
#define EXT2FS_VERSION "0.5"
/*
* Special inodes numbers
*/
#define EXT2_BAD_INO 1 /* Bad blocks inode */
#define EXT2_ROOT_INO 2 /* Root inode */
#define EXT2_ACL_IDX_INO 3 /* ACL inode */
#define EXT2_ACL_DATA_INO 4 /* ACL inode */
#define EXT2_BOOT_LOADER_INO 5 /* Boot loader inode */
#define EXT2_UNDEL_DIR_INO 6 /* Undelete directory inode */
#define EXT2_FIRST_INO 11 /* First non reserved inode */
/*
* The second extended file system magic number
*/
#define EXT2_PRE_02B_MAGIC 0xEF51
#define EXT2_SUPER_MAGIC 0xEF53
#define EXT2_SUPER_BIGMAGIC 0x53EF /* Accessing on big-endian system... */
/*
* Maximal count of links to a file
*/
#define EXT2_LINK_MAX 32000
/*
* Macro-instructions used to manage several block sizes
*/
#define EXT2_MIN_BLOCK_SIZE 1024
#define EXT2_MAX_BLOCK_SIZE 4096
#define EXT2_MIN_BLOCK_LOG_SIZE 10
# define EXT2_BLOCK_SIZE(s) (EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size)
#define EXT2_ACLE_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_acl_entry))
#define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (unsigned int))
# define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_log_block_size + 10)
#define EXT2_INODES_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_inode))
/*
* Macro-instructions used to manage fragments
*/
#define EXT2_MIN_FRAG_SIZE 1024
#define EXT2_MAX_FRAG_SIZE 4096
#define EXT2_MIN_FRAG_LOG_SIZE 10
# define EXT2_FRAG_SIZE(s) (EXT2_MIN_FRAG_SIZE << (s)->s_log_frag_size)
# define EXT2_FRAGS_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s))
/*
* ACL structures
*/
struct ext2_acl_header /* Header of Access Control Lists */
{
unsigned int aclh_size;
unsigned int aclh_file_count;
unsigned int aclh_acle_count;
unsigned int aclh_first_acle;
};
struct ext2_acl_entry /* Access Control List Entry */
{
unsigned int acle_size;
unsigned short acle_perms; /* Access permissions */
unsigned short acle_type; /* Type of entry */
unsigned short acle_tag; /* User or group identity */
unsigned short acle_pad1;
unsigned int acle_next; /* Pointer on next entry for the */
/* same inode or on next free entry */
};
/*
* Structure of a blocks group descriptor
*/
struct ext2_old_group_desc
{
unsigned int bg_block_bitmap; /* Blocks bitmap block */
unsigned int bg_inode_bitmap; /* Inodes bitmap block */
unsigned int bg_inode_table; /* Inodes table block */
unsigned short bg_free_blocks_count; /* Free blocks count */
unsigned short bg_free_inodes_count; /* Free inodes count */
};
struct ext2_group_desc
{
unsigned int bg_block_bitmap; /* Blocks bitmap block */
unsigned int bg_inode_bitmap; /* Inodes bitmap block */
unsigned int bg_inode_table; /* Inodes table block */
unsigned short bg_free_blocks_count; /* Free blocks count */
unsigned short bg_free_inodes_count; /* Free inodes count */
unsigned short bg_used_dirs_count; /* Directories count */
unsigned short bg_pad;
unsigned int bg_reserved[3];
};
/*
* Macro-instructions used to manage group descriptors
*/
# define EXT2_BLOCKS_PER_GROUP(s) ((s)->s_blocks_per_group)
# define EXT2_DESC_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc))
# define EXT2_INODES_PER_GROUP(s) ((s)->s_inodes_per_group)
/*
* Constants relative to the data blocks
*/
#define EXT2_NDIR_BLOCKS 12
#define EXT2_IND_BLOCK EXT2_NDIR_BLOCKS
#define EXT2_DIND_BLOCK (EXT2_IND_BLOCK + 1)
#define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1)
#define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1)
/*
* Inode flags
*/
#define EXT2_SECRM_FL 0x0001 /* Secure deletion */
#define EXT2_UNRM_FL 0x0002 /* Undelete */
#define EXT2_COMPR_FL 0x0004 /* Compress file */
#define EXT2_SYNC_FL 0x0008 /* Synchronous updates */
/*
* ioctl commands
*/
#define EXT2_IOC_GETFLAGS _IOR('f', 1, int)
#define EXT2_IOC_SETFLAGS _IOW('f', 2, int)
#define EXT2_IOC_GETVERSION _IOR('v', 1, int)
#define EXT2_IOC_SETVERSION _IOW('v', 2, int)
/*
* Structure of an inode on the disk
*/
struct ext2_inode {
unsigned short i_mode; /* File mode */
unsigned short i_uid; /* Owner Uid */
unsigned int i_size; /* Size in bytes */
unsigned int i_atime; /* Access time */
unsigned int i_ctime; /* Creation time */
unsigned int i_mtime; /* Modification time */
unsigned int i_dtime; /* Deletion Time */
unsigned short i_gid; /* Group Id */
unsigned short i_links_count; /* Links count */
unsigned int i_blocks; /* Blocks count */
unsigned int i_flags; /* File flags */
unsigned int i_reserved1;
unsigned int i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
unsigned int i_version; /* File version (for NFS) */
unsigned int i_file_acl; /* File ACL */
unsigned int i_dir_acl; /* Directory ACL */
unsigned int i_faddr; /* Fragment address */
unsigned char i_frag; /* Fragment number */
unsigned char i_fsize; /* Fragment size */
unsigned short i_pad1;
unsigned int i_reserved2[2];
};
/*
* File system states
*/
#define EXT2_VALID_FS 0x0001 /* Unmounted cleany */
#define EXT2_ERROR_FS 0x0002 /* Errors detected */
/*
* Mount flags
*/
#define EXT2_MOUNT_CHECK_NORMAL 0x0001 /* Do some more checks */
#define EXT2_MOUNT_CHECK_STRICT 0x0002 /* Do again more checks */
#define EXT2_MOUNT_CHECK (EXT2_MOUNT_CHECK_NORMAL | \
EXT2_MOUNT_CHECK_STRICT)
#define EXT2_MOUNT_GRPID 0x0004 /* Create files with directory's group */
#define EXT2_MOUNT_DEBUG 0x0008 /* Some debugging messages */
#define EXT2_MOUNT_ERRORS_CONT 0x0010 /* Continue on errors */
#define EXT2_MOUNT_ERRORS_RO 0x0020 /* Remount fs ro on errors */
#define EXT2_MOUNT_ERRORS_PANIC 0x0040 /* Panic on errors */
#define clear_opt(o, opt) o &= ~EXT2_MOUNT_##opt
#define set_opt(o, opt) o |= EXT2_MOUNT_##opt
#define test_opt(sb, opt) ((sb)->u.ext2_sb.s_mount_opt & \
EXT2_MOUNT_##opt)
/*
* Maximal mount counts between two filesystem checks
*/
#define EXT2_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */
#define EXT2_DFL_CHECKINTERVAL 0 /* Don't use interval check */
/*
* Behaviour when detecting errors
*/
#define EXT2_ERRORS_CONTINUE 1 /* Continue execution */
#define EXT2_ERRORS_RO 2 /* Remount fs read-only */
#define EXT2_ERRORS_PANIC 3 /* Panic */
#define EXT2_ERRORS_DEFAULT EXT2_ERRORS_CONTINUE
/*
* Structure of the super block
*/
struct ext2_super_block {
unsigned int s_inodes_count; /* 0: Inodes count */
unsigned int s_blocks_count; /* 4: Blocks count */
unsigned int s_r_blocks_count;/* 8: Reserved blocks count */
unsigned int s_free_blocks_count;/* 12: Free blocks count */
unsigned int s_free_inodes_count;/* 16: Free inodes count */
unsigned int s_first_data_block;/* 20: First Data Block */
unsigned int s_log_block_size;/* 24: Block size */
int s_log_frag_size; /* 28: Fragment size */
unsigned int s_blocks_per_group;/* 32: # Blocks per group */
unsigned int s_frags_per_group;/* 36: # Fragments per group */
unsigned int s_inodes_per_group;/* 40: # Inodes per group */
unsigned int s_mtime; /* 44: Mount time */
unsigned int s_wtime; /* 48: Write time */
unsigned short s_mnt_count; /* 52: Mount count */
short s_max_mnt_count; /* 54: Maximal mount count */
unsigned short s_magic; /* 56: Magic signature */
unsigned short s_state; /* 58: File system state */
unsigned short s_errors; /* 60: Behaviour when detecting errors */
unsigned short s_pad; /* 62: */
unsigned int s_lastcheck; /* 64: time of last check */
unsigned int s_checkinterval; /* 68: max. time between checks */
unsigned int s_reserved[238]; /* 72: Padding to the end of the block */
};
/*
* Structure of a directory entry
*/
#define EXT2_NAME_LEN 255
struct ext2_dir_entry {
unsigned int inode; /* Inode number */
unsigned short rec_len; /* Directory entry length */
unsigned short name_len; /* Name length */
char name[EXT2_NAME_LEN]; /* File name */
};
/*
* EXT2_DIR_PAD defines the directory entries boundaries
*
* NOTE: It must be a multiple of 4
*/
#define EXT2_DIR_PAD 4
#define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1)
#define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & \
~EXT2_DIR_ROUND)
/* These definitions are cribbed from other file system include files, so that
* we can take a stab at identifying non-ext2 file systems as well...
*/
/*
* minix super-block data on disk
*/
struct minix_super_block {
unsigned short s_ninodes;
unsigned short s_nzones;
unsigned short s_imap_blocks;
unsigned short s_zmap_blocks;
unsigned short s_firstdatazone;
unsigned short s_log_zone_size;
unsigned int s_max_size;
unsigned short s_magic;
unsigned short s_state;
};
#define MINIX_SUPER_MAGIC 0x137F /* original minix fs */
#define MINIX_SUPER_MAGIC2 0x138F /* minix fs, 30 char names */
#define NEW_MINIX_SUPER_MAGIC 0x2468 /* minix V2 - not implemented */
extern int ext2_init(char * name, int access);
extern void ext2_close();
extern struct ext2_inode * ext2_iget(int ino);
extern void ext2_iput(struct ext2_inode *ip);
extern int ext2_balloc(void);
extern int ext2_ialloc(void);
extern int ext2_blocksize(void);
extern int ext2_blkno(struct ext2_inode *ip, int blkoff,
int allocate);
extern void ext2_bread(struct ext2_inode *ip, int blkno,
char * buffer);
extern void ext2_bwrite(struct ext2_inode *ip, int blkno,
char * buffer);
extern struct ext2_inode * ext2_namei(char * name);
extern void ext2_truncate(struct ext2_inode *ip);
extern void ext2_mknod(struct ext2_inode *dip,
char * name, int ino);
extern int ext2_fill_contiguous(struct ext2_inode * ip,
int nblocks);
extern void ext2_write_bootblock(char *bb);
#endif /* EXT2_LIB_H */
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