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422 giacomo 1
#ifndef __CRAMFS_H
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#define __CRAMFS_H
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#ifndef __KERNEL__
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typedef unsigned char u8;
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typedef unsigned short u16;
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typedef unsigned int u32;
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#endif
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#define CRAMFS_MAGIC            0x28cd3d45      /* some random number */
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#define CRAMFS_SIGNATURE        "Compressed ROMFS"
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/*
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 * Width of various bitfields in struct cramfs_inode.
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 * Primarily used to generate warnings in mkcramfs.
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 */
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#define CRAMFS_MODE_WIDTH 16
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#define CRAMFS_UID_WIDTH 16
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#define CRAMFS_SIZE_WIDTH 24
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#define CRAMFS_GID_WIDTH 8
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#define CRAMFS_NAMELEN_WIDTH 6
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#define CRAMFS_OFFSET_WIDTH 26
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/*
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 * Since inode.namelen is a unsigned 6-bit number, the maximum cramfs
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 * path length is 63 << 2 = 252.
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 */
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#define CRAMFS_MAXPATHLEN (((1 << CRAMFS_NAMELEN_WIDTH) - 1) << 2)
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/*
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 * Reasonably terse representation of the inode data.
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 */
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struct cramfs_inode {
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        u32 mode:CRAMFS_MODE_WIDTH, uid:CRAMFS_UID_WIDTH;
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        /* SIZE for device files is i_rdev */
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        u32 size:CRAMFS_SIZE_WIDTH, gid:CRAMFS_GID_WIDTH;
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        /* NAMELEN is the length of the file name, divided by 4 and
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           rounded up.  (cramfs doesn't support hard links.) */
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        /* OFFSET: For symlinks and non-empty regular files, this
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           contains the offset (divided by 4) of the file data in
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           compressed form (starting with an array of block pointers;
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           see README).  For non-empty directories it is the offset
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           (divided by 4) of the inode of the first file in that
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           directory.  For anything else, offset is zero. */
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        u32 namelen:CRAMFS_NAMELEN_WIDTH, offset:CRAMFS_OFFSET_WIDTH;
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};
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struct cramfs_info {
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        u32 crc;
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        u32 edition;
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        u32 blocks;
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        u32 files;
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};
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/*
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 * Superblock information at the beginning of the FS.
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 */
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struct cramfs_super {
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        u32 magic;                      /* 0x28cd3d45 - random number */
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        u32 size;                       /* length in bytes */
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        u32 flags;                      /* feature flags */
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        u32 future;                     /* reserved for future use */
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        u8 signature[16];               /* "Compressed ROMFS" */
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        struct cramfs_info fsid;        /* unique filesystem info */
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        u8 name[16];                    /* user-defined name */
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        struct cramfs_inode root;       /* root inode data */
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};
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/*
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 * Feature flags
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 *
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 * 0x00000000 - 0x000000ff: features that work for all past kernels
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 * 0x00000100 - 0xffffffff: features that don't work for past kernels
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 */
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#define CRAMFS_FLAG_FSID_VERSION_2      0x00000001      /* fsid version #2 */
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#define CRAMFS_FLAG_SORTED_DIRS         0x00000002      /* sorted dirs */
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#define CRAMFS_FLAG_HOLES               0x00000100      /* support for holes */
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#define CRAMFS_FLAG_WRONG_SIGNATURE     0x00000200      /* reserved */
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#define CRAMFS_FLAG_SHIFTED_ROOT_OFFSET 0x00000400      /* shifted root fs */
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/*
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 * Valid values in super.flags.  Currently we refuse to mount
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 * if (flags & ~CRAMFS_SUPPORTED_FLAGS).  Maybe that should be
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 * changed to test super.future instead.
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 */
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#define CRAMFS_SUPPORTED_FLAGS  ( 0x000000ff \
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                                | CRAMFS_FLAG_HOLES \
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                                | CRAMFS_FLAG_WRONG_SIGNATURE \
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                                | CRAMFS_FLAG_SHIFTED_ROOT_OFFSET )
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/* Uncompression interfaces to the underlying zlib */
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int cramfs_uncompress_block(void *dst, int dstlen, void *src, int srclen);
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int cramfs_uncompress_init(void);
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int cramfs_uncompress_exit(void);
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#endif