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/*
* macros to convert each packed bitfield structure from little endian to big
* endian and vice versa. These are needed when creating a filesystem on a
* machine with different byte ordering to the target architecture.
*
* Copyright (c) 2002, 2003, 2004, 2005, 2006
* Phillip Lougher <phillip@lougher.demon.co.uK>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2,
* or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* mksquashfs.h
*
*/
/*
* macros used to swap each structure entry, taking into account
* bitfields and different bitfield placing conventions on differing architectures
*/
#if __BYTE_ORDER == __BIG_ENDIAN
/* convert from big endian to little endian */
#define SQUASHFS_SWAP(value, p, pos, tbits) _SQUASHFS_SWAP(value, p, pos, tbits, b_pos)
#else
/* convert from little endian to big endian */
#define SQUASHFS_SWAP(value, p, pos, tbits) _SQUASHFS_SWAP(value, p, pos, tbits, 64 - tbits - b_pos)
#endif
#define _SQUASHFS_SWAP(value, p, pos, tbits, SHIFT) {\
int bits;\
int b_pos = pos % 8;\
unsigned long long val = (long long) value << (SHIFT);\
unsigned char *s = ((unsigned char *) &val) + 7;\
unsigned char *d = ((unsigned char *)p) + (pos / 8);\
for(bits = 0; bits < (tbits + b_pos); bits += 8) \
*d++ |= *s--;\
}
#define SQUASHFS_MEMSET(s, d, n) memset(d, 0, n);
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