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cramfs: use stdint.h instead of u{8,16,32}
[thirdparty/util-linux.git] / disk-utils / cramfs.h
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1/*
2 * cramfs_common - cramfs common code
3 *
4 * Copyright (c) 2008 Roy Peled, the.roy.peled -at- gmail
5 * Copyright (c) 2004-2006 by Michael Holzt, kju -at- fqdn.org
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 */
18
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19#ifndef __CRAMFS_H
20#define __CRAMFS_H
21
d51f37a3 22#include <stdint.h>
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23
24#define CRAMFS_MAGIC 0x28cd3d45 /* some random number */
25#define CRAMFS_SIGNATURE "Compressed ROMFS"
26
27/*
28 * Width of various bitfields in struct cramfs_inode.
29 * Primarily used to generate warnings in mkcramfs.
30 */
31#define CRAMFS_MODE_WIDTH 16
32#define CRAMFS_UID_WIDTH 16
33#define CRAMFS_SIZE_WIDTH 24
34#define CRAMFS_GID_WIDTH 8
35#define CRAMFS_NAMELEN_WIDTH 6
36#define CRAMFS_OFFSET_WIDTH 26
37
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38#ifndef HOST_IS_BIG_ENDIAN
39#ifdef WORDS_BIGENDIAN
40#define HOST_IS_BIG_ENDIAN 1
41#else
42#define HOST_IS_BIG_ENDIAN 0
43#endif
44#endif
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45
46/*
47 * Reasonably terse representation of the inode data.
48 */
49struct cramfs_inode {
d51f37a3 50 uint32_t mode:16, uid:16;
63cccae4 51 /* SIZE for device files is i_rdev */
d51f37a3 52 uint32_t size:24, gid:8;
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53 /* NAMELEN is the length of the file name, divided by 4 and
54 rounded up. (cramfs doesn't support hard links.) */
55 /* OFFSET: For symlinks and non-empty regular files, this
56 contains the offset (divided by 4) of the file data in
57 compressed form (starting with an array of block pointers;
58 see README). For non-empty directories it is the offset
59 (divided by 4) of the inode of the first file in that
60 directory. For anything else, offset is zero. */
d51f37a3 61 uint32_t namelen:6, offset:26;
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62};
63
64struct cramfs_info {
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65 uint32_t crc;
66 uint32_t edition;
67 uint32_t blocks;
68 uint32_t files;
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69};
70
71/*
72 * Superblock information at the beginning of the FS.
73 */
74struct cramfs_super {
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75 uint32_t magic; /* 0x28cd3d45 - random number */
76 uint32_t size; /* Not used. mkcramfs currently
63cccae4 77 writes a constant 1<<16 here. */
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78 uint32_t flags; /* 0 */
79 uint32_t future; /* 0 */
80 uint8_t signature[16]; /* "Compressed ROMFS" */
63cccae4 81 struct cramfs_info fsid;/* unique filesystem info */
d51f37a3 82 uint8_t name[16]; /* user-defined name */
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83 struct cramfs_inode root; /* Root inode data */
84};
85
86#define CRAMFS_FLAG_FSID_VERSION_2 0x00000001 /* fsid version #2 */
87#define CRAMFS_FLAG_SORTED_DIRS 0x00000002 /* sorted dirs */
88#define CRAMFS_FLAG_HOLES 0x00000100 /* support for holes */
89#define CRAMFS_FLAG_WRONG_SIGNATURE 0x00000200 /* reserved */
90#define CRAMFS_FLAG_SHIFTED_ROOT_OFFSET 0x00000400 /* shifted root fs */
91
92/*
93 * Valid values in super.flags. Currently we refuse to mount
94 * if (flags & ~CRAMFS_SUPPORTED_FLAGS). Maybe that should be
95 * changed to test super.future instead.
96 */
97#define CRAMFS_SUPPORTED_FLAGS (0xff)
98
99/* Uncompression interfaces to the underlying zlib */
100int cramfs_uncompress_block(void *dst, int dstlen, void *src, int srclen);
101int cramfs_uncompress_init(void);
102int cramfs_uncompress_exit(void);
103
d51f37a3 104uint32_t u32_toggle_endianness(int big_endian, uint32_t what);
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105void super_toggle_endianness(int from_big_endian, struct cramfs_super *super);
106void inode_to_host(int from_big_endian, struct cramfs_inode *inode_in, struct cramfs_inode *inode_out);
107void inode_from_host(int to_big_endian, struct cramfs_inode *inode_in, struct cramfs_inode *inode_out);
108
63cccae4 109#endif