]>
git.ipfire.org Git - thirdparty/util-linux.git/blob - disk-utils/cramfs_common.c
2 * SPDX-License-Identifier: GPL-2.0-or-later
4 * cramfs_common - cramfs common code
6 * Copyright (c) 2008 Roy Peled, the.roy.peled -at- gmail.com
7 * Copyright (c) 2004-2006 by Juliane Holzt, kju -at- fqdn.org
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
23 #include "../include/bitops.h"
25 uint32_t u32_toggle_endianness(int big_endian
, uint32_t what
)
27 return big_endian
== HOST_IS_BIG_ENDIAN
? what
: swab32(what
);
30 void super_toggle_endianness(int big_endian
, struct cramfs_super
*super
)
32 if (big_endian
!= HOST_IS_BIG_ENDIAN
) {
33 super
->magic
= swab32(super
->magic
);
34 super
->size
= swab32(super
->size
);
35 super
->flags
= swab32(super
->flags
);
36 super
->future
= swab32(super
->future
);
37 super
->fsid
.crc
= swab32(super
->fsid
.crc
);
38 super
->fsid
.edition
= swab32(super
->fsid
.edition
);
39 super
->fsid
.blocks
= swab32(super
->fsid
.blocks
);
40 super
->fsid
.files
= swab32(super
->fsid
.files
);
44 static void inode_toggle_endianness(int input_big_endian
, int output_big_endian
,
45 struct cramfs_inode
*inode_in
,
46 struct cramfs_inode
*inode_out
)
48 if (input_big_endian
== output_big_endian
) {
49 memmove(inode_out
, inode_in
, sizeof(*inode_out
));
51 unsigned char inode_out_buf
[sizeof(*inode_in
)];
52 unsigned char *inode_in_buf
= (unsigned char*)inode_in
;
54 inode_out_buf
[0] = inode_in_buf
[1]; /* 16 bit: mode */
55 inode_out_buf
[1] = inode_in_buf
[0];
57 inode_out_buf
[2] = inode_in_buf
[3]; /* 16 bit: uid */
58 inode_out_buf
[3] = inode_in_buf
[2];
60 inode_out_buf
[4] = inode_in_buf
[6]; /* 24 bit: size */
61 inode_out_buf
[5] = inode_in_buf
[5];
62 inode_out_buf
[6] = inode_in_buf
[4];
64 inode_out_buf
[7] = inode_in_buf
[7]; /* 8 bit: gid width */
67 * Stop the madness! Outlaw C bitfields! They are unportable
68 * and nasty! See for yourself what a mess this is:
70 if (output_big_endian
) {
71 inode_out_buf
[ 8] = ( (inode_in_buf
[ 8]&0x3F) << 2 ) |
72 ( (inode_in_buf
[11]&0xC0) >> 6 );
74 inode_out_buf
[ 9] = ( (inode_in_buf
[11]&0x3F) << 2 ) |
75 ( (inode_in_buf
[10]&0xC0) >> 6 );
77 inode_out_buf
[10] = ( (inode_in_buf
[10]&0x3F) << 2 ) |
78 ( (inode_in_buf
[ 9]&0xC0) >> 6 );
80 inode_out_buf
[11] = ( (inode_in_buf
[ 9]&0x3F) << 2 ) |
81 ( (inode_in_buf
[ 8]&0xC0) >> 6 );
83 inode_out_buf
[ 8] = ( (inode_in_buf
[ 8]&0xFD) >> 2 ) |
84 ( (inode_in_buf
[11]&0x03) << 6 );
86 inode_out_buf
[ 9] = ( (inode_in_buf
[11]&0xFD) >> 2 ) |
87 ( (inode_in_buf
[10]&0x03) << 6 );
89 inode_out_buf
[10] = ( (inode_in_buf
[10]&0xFD) >> 2 ) |
90 ( (inode_in_buf
[ 9]&0x03) << 6 );
92 inode_out_buf
[11] = ( (inode_in_buf
[ 9]&0xFD) >> 2 ) |
93 ( (inode_in_buf
[ 8]&0x03) << 6 );
95 memmove(inode_out
, inode_out_buf
, sizeof(*inode_out
));
99 void inode_to_host(int from_big_endian
, struct cramfs_inode
*inode_in
,
100 struct cramfs_inode
*inode_out
)
102 inode_toggle_endianness(from_big_endian
, HOST_IS_BIG_ENDIAN
, inode_in
,
106 void inode_from_host(int to_big_endian
, struct cramfs_inode
*inode_in
,
107 struct cramfs_inode
*inode_out
)
109 inode_toggle_endianness(HOST_IS_BIG_ENDIAN
, to_big_endian
, inode_in
,