endians.h revision 7e7bd3dccbfe8f79e25e5c1554b5bc3a9aaca321
/*
* endians.h - Definitions related to handling of byte ordering. Part of the
* Linux-NTFS project.
*
* Copyright (c) 2000-2005 Anton Altaparmakov
* Copyright (c) 2007 Yura Pakhuchiy
*
* This program/include file 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 of the License, or
* (at your option) any later version.
*
* This program/include file 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 (in the main directory of the Linux-NTFS
* distribution in the file COPYING); if not, write to the Free Software
* Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef _NTFS_ENDIANS_H
#define _NTFS_ENDIANS_H
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
/*
* Notes:
* We define the conversion functions including typecasts since the
* defaults don't necessarily perform appropriate typecasts.
* Also, using our own functions means that we can change them if it
* turns out that we do need to use the unaligned access macros on
* architectures requiring aligned memory accesses...
*/
#ifdef HAVE_ENDIAN_H
#include <endian.h>
#endif
#ifdef HAVE_SYS_ENDIAN_H
#include <sys/endian.h>
#endif
#ifdef HAVE_MACHINE_ENDIAN_H
#include <machine/endian.h>
#endif
#ifdef HAVE_SYS_BYTEORDER_H
#include <sys/byteorder.h>
#endif
#ifdef HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif
#ifndef __BYTE_ORDER
# if defined(_BYTE_ORDER)
# define __BYTE_ORDER _BYTE_ORDER
# define __LITTLE_ENDIAN _LITTLE_ENDIAN
# define __BIG_ENDIAN _BIG_ENDIAN
# elif defined(BYTE_ORDER)
# define __BYTE_ORDER BYTE_ORDER
# define __LITTLE_ENDIAN LITTLE_ENDIAN
# define __BIG_ENDIAN BIG_ENDIAN
# elif defined(__BYTE_ORDER__)
# define __BYTE_ORDER __BYTE_ORDER__
# define __LITTLE_ENDIAN __LITTLE_ENDIAN__
# define __BIG_ENDIAN __BIG_ENDIAN__
# elif (defined(_LITTLE_ENDIAN) && !defined(_BIG_ENDIAN)) || \
defined(WORDS_LITTLEENDIAN)
# define __BYTE_ORDER 1
# define __LITTLE_ENDIAN 1
# define __BIG_ENDIAN 0
# elif (!defined(_LITTLE_ENDIAN) && defined(_BIG_ENDIAN)) || \
defined(WORDS_BIGENDIAN)
# define __BYTE_ORDER 0
# define __LITTLE_ENDIAN 1
# define __BIG_ENDIAN 0
# else
# error "__BYTE_ORDER is not defined."
# endif
#endif
#define __ntfs_bswap_constant_16(x) \
(u16)((((u16)(x) & 0xff00) >> 8) | \
(((u16)(x) & 0x00ff) << 8))
#define __ntfs_bswap_constant_32(x) \
(u32)((((u32)(x) & 0xff000000u) >> 24) | \
(((u32)(x) & 0x00ff0000u) >> 8) | \
(((u32)(x) & 0x0000ff00u) << 8) | \
(((u32)(x) & 0x000000ffu) << 24))
#define __ntfs_bswap_constant_64(x) \
(u64)((((u64)(x) & 0xff00000000000000ull) >> 56) | \
(((u64)(x) & 0x00ff000000000000ull) >> 40) | \
(((u64)(x) & 0x0000ff0000000000ull) >> 24) | \
(((u64)(x) & 0x000000ff00000000ull) >> 8) | \
(((u64)(x) & 0x00000000ff000000ull) << 8) | \
(((u64)(x) & 0x0000000000ff0000ull) << 24) | \
(((u64)(x) & 0x000000000000ff00ull) << 40) | \
(((u64)(x) & 0x00000000000000ffull) << 56))
#ifdef HAVE_BYTESWAP_H
# include <byteswap.h>
#else
# define bswap_16(x) __ntfs_bswap_constant_16(x)
# define bswap_32(x) __ntfs_bswap_constant_32(x)
# define bswap_64(x) __ntfs_bswap_constant_64(x)
#endif
#if defined(__LITTLE_ENDIAN) && (__BYTE_ORDER == __LITTLE_ENDIAN)
#define __le16_to_cpu(x) ((__force u16)(x))
#define __le32_to_cpu(x) ((__force u32)(x))
#define __le64_to_cpu(x) ((__force u64)(x))
#define __cpu_to_le16(x) ((__force le16)(x))
#define __cpu_to_le32(x) ((__force le32)(x))
#define __cpu_to_le64(x) ((__force le64)(x))
#define __constant_le16_to_cpu(x) ((__force u16)(x))
#define __constant_le32_to_cpu(x) ((__force u32)(x))
#define __constant_le64_to_cpu(x) ((__force u64)(x))
#define __constant_cpu_to_le16(x) ((__force le16)(x))
#define __constant_cpu_to_le32(x) ((__force le32)(x))
#define __constant_cpu_to_le64(x) ((__force le64)(x))
#elif defined(__BIG_ENDIAN) && (__BYTE_ORDER == __BIG_ENDIAN)
#define __le16_to_cpu(x) bswap_16((__force u16)(x))
#define __le32_to_cpu(x) bswap_32((__force u16)(x))
#define __le64_to_cpu(x) bswap_64((__force u16)(x))
#define __cpu_to_le16(x) (__force le16)bswap_16((__force u16)(x))
#define __cpu_to_le32(x) (__force le32)bswap_32((__force u32)(x))
#define __cpu_to_le64(x) (__force le64)bswap_64((__force u64)(x))
#define __constant_le16_to_cpu(x) __ntfs_bswap_constant_16((__force u16)(x))
#define __constant_le32_to_cpu(x) __ntfs_bswap_constant_32((__force u32)(x))
#define __constant_le64_to_cpu(x) __ntfs_bswap_constant_64((__force u64)(x))
#define __constant_cpu_to_le16(x) \
(__force le16)__ntfs_bswap_constant_16((__force u16)(x))
#define __constant_cpu_to_le32(x) \
(__force le32)__ntfs_bswap_constant_32((__force u32)(x))
#define __constant_cpu_to_le64(x) \
(__force le64)__ntfs_bswap_constant_64((__force u64)(x))
#else
#error "You must define __BYTE_ORDER to be __LITTLE_ENDIAN or __BIG_ENDIAN."
#endif
/* Unsigned from LE to CPU conversion. */
#define le16_to_cpu(x) (u16)__le16_to_cpu((le16)(x))
#define le32_to_cpu(x) (u32)__le32_to_cpu((le32)(x))
#define le64_to_cpu(x) (u64)__le64_to_cpu((le64)(x))
#define le16_to_cpup(x) (u16)__le16_to_cpu(*(const le16*)(x))
#define le32_to_cpup(x) (u32)__le32_to_cpu(*(const le32*)(x))
#define le64_to_cpup(x) (u64)__le64_to_cpu(*(const le64*)(x))
/* Signed from LE to CPU conversion. */
#define sle16_to_cpu(x) (s16)__le16_to_cpu((sle16)(x))
#define sle32_to_cpu(x) (s32)__le32_to_cpu((sle32)(x))
#define sle64_to_cpu(x) (s64)__le64_to_cpu((sle64)(x))
#define sle16_to_cpup(x) (s16)__le16_to_cpu(*(const sle16*)(x))
#define sle32_to_cpup(x) (s32)__le32_to_cpu(*(const sle32*)(x))
#define sle64_to_cpup(x) (s64)__le64_to_cpu(*(const sle64*)(x))
/* Unsigned from CPU to LE conversion. */
#define cpu_to_le16(x) (le16)__cpu_to_le16((u16)(x))
#define cpu_to_le32(x) (le32)__cpu_to_le32((u32)(x))
#define cpu_to_le64(x) (le64)__cpu_to_le64((u64)(x))
#define cpu_to_le16p(x) (le16)__cpu_to_le16(*(const u16*)(x))
#define cpu_to_le32p(x) (le32)__cpu_to_le32(*(const u32*)(x))
#define cpu_to_le64p(x) (le64)__cpu_to_le64(*(const u64*)(x))
/* Signed from CPU to LE conversion. */
#define cpu_to_sle16(x) (__force sle16)__cpu_to_le16((s16)(x))
#define cpu_to_sle32(x) (__force sle32)__cpu_to_le32((s32)(x))
#define cpu_to_sle64(x) (__force sle64)__cpu_to_le64((s64)(x))
#define cpu_to_sle16p(x) (__force sle16)__cpu_to_le16(*(const s16*)(x))
#define cpu_to_sle32p(x) (__force sle32)__cpu_to_le32(*(const s32*)(x))
#define cpu_to_sle64p(x) (__force sle64)__cpu_to_le64(*(const s64*)(x))
/* Constant endianness conversion defines. */
#define const_le16_to_cpu(x) (u16)__constant_le16_to_cpu((le16)(x))
#define const_le32_to_cpu(x) (u32)__constant_le32_to_cpu((le32)(x))
#define const_le64_to_cpu(x) (u64)__constant_le64_to_cpu((le64)(x))
#define const_cpu_to_le16(x) (le16)__constant_cpu_to_le16((u16)(x))
#define const_cpu_to_le32(x) (le32)__constant_cpu_to_le32((u32)(x))
#define const_cpu_to_le64(x) (le64)__constant_cpu_to_le64((u64)(x))
#ifdef __CHECKER__
static void ntfs_endian_self_test(void)
{
/* Should not generate warnings. */
(le16)cpu_to_le16((u16)1);
(le32)cpu_to_le32((u32)1);
(le64)cpu_to_le64((u64)1);
(sle16)cpu_to_sle16((s16)1);
(sle32)cpu_to_sle32((s32)1);
(sle64)cpu_to_sle64((s64)1);
(u16)le16_to_cpu((__force le16)1);
(u32)le32_to_cpu((__force le32)1);
(u64)le64_to_cpu((__force le64)1);
(s16)sle16_to_cpu((__force sle16)1);
(s32)sle32_to_cpu((__force sle32)1);
(s64)sle64_to_cpu((__force sle64)1);
(le16)const_cpu_to_le16((u16)1);
(le32)const_cpu_to_le32((u32)1);
(le64)const_cpu_to_le64((u64)1);
(u16)const_le16_to_cpu((__force le16)1);
(u32)const_le32_to_cpu((__force le32)1);
(u64)const_le64_to_cpu((__force le64)1);
/*
* TODO: Need some how to test that warnings are actually generated,
* but without flooding output with them and vice-versa print warning
* in case if some one warning is not triggered, but should. (Yura)
*
* I think it can only be done in a ./configure like script / shell
* script that will compile known good and known bad code and pipe the
* output from sparse to a file, then grep the file for the wanted
* warnings/lack thereof and then it would say "Tests: PASS " or
* "Tests: FAILED" or whatever. And you can then hook that into a
* "make test" make target or similar so it is only done when one
* wants to do it... (Anton)
*
* Also we can look on sparse self test script. (Yura)
*/
}
#endif
#endif /* defined _NTFS_ENDIANS_H */