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typedef struct Xfs Xfs;
typedef struct Xfile Xfile;
typedef struct Iobuf Iobuf;
typedef struct Ext2 Ext2;
typedef struct SuperBlock SuperBlock;
typedef struct GroupDesc GroupDesc;
typedef struct Inode Inode;
typedef struct DirEntry DirEntry;
#define SECTORSIZE 512
#define OFFSET_SUPER_BLOCK 1024
#define EXT2_SUPER_MAGIC 0xEF53
#define EXT2_MIN_BLOCK_SIZE 1024
#define EXT2_MAX_BLOCK_SIZE 4096
#define EXT2_ROOT_INODE 2
#define EXT2_FIRST_INO 11
#define EXT2_VALID_FS 0x0001
#define EXT2_ERROR_FS 0x0002
/*
* Structure of the super block
*/
struct SuperBlock {
uint s_inodes_count; /* Inodes count */
uint s_blocks_count; /* Blocks count */
uint s_r_blocks_count; /* Reserved blocks count */
uint s_free_blocks_count; /* Free blocks count */
uint s_free_inodes_count; /* Free inodes count */
uint s_first_data_block; /* First Data Block */
uint s_log_block_size; /* Block size */
int s_log_frag_size; /* Fragment size */
uint s_blocks_per_group; /* # Blocks per group */
uint s_frags_per_group; /* # Fragments per group */
uint s_inodes_per_group; /* # Inodes per group */
uint s_mtime; /* Mount time */
uint 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_pad;
uint s_lastcheck; /* time of last check */
uint s_checkinterval; /* max. time between checks */
uint s_creator_os; /* OS */
uint s_rev_level; /* Revision level */
ushort s_def_resuid; /* Default uid for reserved blocks */
ushort s_def_resgid; /* Default gid for reserved blocks */
uint s_reserved[235]; /* Padding to the end of the block */
};
/*
* Structure of a blocks group descriptor
*/
struct GroupDesc
{
uint bg_block_bitmap; /* Blocks bitmap block */
uint bg_inode_bitmap; /* Inodes bitmap block */
uint bg_inode_table; /* Inodes table block */
ushort bg_free_blocks_count; /* Free blocks count */
ushort bg_free_inodes_count; /* Free inodes count */
ushort bg_used_dirs_count; /* Directories count */
ushort bg_pad;
uint bg_reserved[3];
};
/*
* 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)
/*
* Structure of an inode on the disk
*/
struct Inode {
ushort i_mode; /* File mode */
ushort i_uid; /* Owner Uid */
uint i_size; /* Size in bytes */
uint i_atime; /* Access time */
uint i_ctime; /* Creation time */
uint i_mtime; /* Modification time */
uint i_dtime; /* Deletion Time */
ushort i_gid; /* Group Id */
ushort i_links_count; /* Links count */
uint i_blocks; /* Blocks count */
uint i_flags; /* File flags */
uint osd1;
uint i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
uint i_version; /* File version (for NFS) */
uint i_file_acl; /* File ACL */
uint i_dir_acl; /* Directory ACL */
uint i_faddr; /* Fragment address */
uchar osd2[12];
};
/*
* Structure of a directory entry
*/
#define EXT2_NAME_LEN 255
#define DIR_REC_LEN(name_len) (((name_len) + 8 + 3) & ~3)
struct DirEntry {
uint inode; /* Inode number */
ushort rec_len; /* Directory entry length */
uchar name_len; /* Name length */
uchar reserved;
char name[EXT2_NAME_LEN]; /* File name */
};
#define S_IFMT 00170000
#define S_IFLNK 0120000
#define S_IFREG 0100000
#define S_IFDIR 0040000
#define S_ISLNK(m) (((m) & S_IFMT) == S_IFLNK)
#define S_ISREG(m) (((m) & S_IFMT) == S_IFREG)
#define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
#define DEFAULT_UID 200
#define DEFAULT_GID 100
struct Iobuf
{
Xfs *dev;
long addr;
Iobuf *next;
Iobuf *prev;
Iobuf *hash;
int busy;
int dirty;
char *iobuf;
};
struct Xfs{
Xfs *next;
char *name; /* of file containing external f.s. */
Qid qid; /* of file containing external f.s. */
long ref; /* attach count */
Qid rootqid; /* of plan9 constructed root directory */
short dev;
short fmt;
void *ptr;
/* data from super block */
int block_size;
int desc_per_block;
int inodes_per_group;
int inodes_per_block;
int addr_per_block;
int blocks_per_group;
int ngroups;
int superaddr, superoff;
int grpaddr;
};
struct Xfile{
Xfile *next; /* in hash bucket */
long client;
long fid;
Xfs * xf;
void * ptr;
uint inbr; /* inode nbr */
uint pinbr; /* parrent inode */
ulong bufaddr; /* addr of inode block */
ulong bufoffset;
int root; /* true on attach for ref count */
int dirindex; /* next dir entry to read */
};
#define EXT2_SUPER 1
#define EXT2_DESC 2
#define EXT2_BBLOCK 3
#define EXT2_BINODE 4
struct Ext2{
char type;
union{
SuperBlock *sb;
GroupDesc *gd;
char *bmp;
}u;
Iobuf *buf;
};
#define DESC_ADDR(xf,n) ( (xf)->grpaddr + ((n)/(xf)->desc_per_block) )
#define DESC_OFFSET(xf,d,n) ( ((GroupDesc *)(d)) + ((n)%(xf)->desc_per_block) )
enum{
Asis, Clean, Clunk
};
enum{
Enevermind,
Eformat,
Eio,
Enomem,
Enonexist,
Eexist,
Eperm,
Enofilsys,
Eauth,
Enospace,
Elink,
Elongname,
Eintern,
Ecorrupt,
Enotclean
};
extern int chatty;
extern int errno;
extern char *deffile;
extern int rdonly;
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