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#ifndef __CRAMFS_H

#define __CRAMFS_H

#include <linux/types.h>

#define CRAMFS_MAGIC            0x28cd3d45      /* some random number */

#define CRAMFS_MAGIC_WEND       0x453dcd28      /* magic number with the wrong endianess */

#define CRAMFS_SIGNATURE        "Compressed ROMFS"

/*

 * Width of various bitfields in struct cramfs_inode.

 * Primarily used to generate warnings in mkcramfs.

 */

#define CRAMFS_MODE_WIDTH 16

#define CRAMFS_UID_WIDTH 16

#define CRAMFS_SIZE_WIDTH 24

#define CRAMFS_GID_WIDTH 8

#define CRAMFS_NAMELEN_WIDTH 6

#define CRAMFS_OFFSET_WIDTH 26

/*

 * Since inode.namelen is a unsigned 6-bit number, the maximum cramfs

 * path length is 63 << 2 = 252.

 */

#define CRAMFS_MAXPATHLEN (((1 << CRAMFS_NAMELEN_WIDTH) - 1) << 2)

/*

 * Reasonably terse representation of the inode data.

 */

struct cramfs_inode {

        __u32 mode:CRAMFS_MODE_WIDTH, uid:CRAMFS_UID_WIDTH;

        /* SIZE for device files is i_rdev */

        __u32 size:CRAMFS_SIZE_WIDTH, gid:CRAMFS_GID_WIDTH;

        /* NAMELEN is the length of the file name, divided by 4 and

           rounded up.  (cramfs doesn't support hard links.) */

        /* OFFSET: For symlinks and non-empty regular files, this

           contains the offset (divided by 4) of the file data in

           compressed form (starting with an array of block pointers;

           see README).  For non-empty directories it is the offset

           (divided by 4) of the inode of the first file in that

           directory.  For anything else, offset is zero. */

        __u32 namelen:CRAMFS_NAMELEN_WIDTH, offset:CRAMFS_OFFSET_WIDTH;

};

struct cramfs_info {

        __u32 crc;

        __u32 edition;

        __u32 blocks;

        __u32 files;

};

/*

 * Superblock information at the beginning of the FS.

 */

struct cramfs_super {

        __u32 magic;                    /* 0x28cd3d45 - random number */

        __u32 size;                     /* length in bytes */

        __u32 flags;                    /* feature flags */

        __u32 future;                   /* reserved for future use */

        __u8 signature[16];             /* "Compressed ROMFS" */

        struct cramfs_info fsid;        /* unique filesystem info */

        __u8 name[16];                  /* user-defined name */

        struct cramfs_inode root;       /* root inode data */

};

/*

 * Feature flags

 *

 * 0x00000000 - 0x000000ff: features that work for all past kernels

 * 0x00000100 - 0xffffffff: features that don't work for past kernels

 */

#define CRAMFS_FLAG_FSID_VERSION_2      0x00000001      /* fsid version #2 */

#define CRAMFS_FLAG_SORTED_DIRS         0x00000002      /* sorted dirs */

#define CRAMFS_FLAG_HOLES               0x00000100      /* support for holes */

#define CRAMFS_FLAG_WRONG_SIGNATURE     0x00000200      /* reserved */

#define CRAMFS_FLAG_SHIFTED_ROOT_OFFSET 0x00000400      /* shifted root fs */

/*

 * Valid values in super.flags.  Currently we refuse to mount

 * if (flags & ~CRAMFS_SUPPORTED_FLAGS).  Maybe that should be

 * changed to test super.future instead.

 */

#define CRAMFS_SUPPORTED_FLAGS  ( 0x000000ff \

                                | CRAMFS_FLAG_HOLES \

                                | CRAMFS_FLAG_WRONG_SIGNATURE \

                                | CRAMFS_FLAG_SHIFTED_ROOT_OFFSET )

/* Uncompression interfaces to the underlying zlib */

int cramfs_uncompress_block(void *dst, int dstlen, void *src, int srclen);

int cramfs_uncompress_init(void);

void cramfs_uncompress_exit(void);

#endif