English
- #ifndef _LINUX_BYTEORDER_SWAB_H
- #define _LINUX_BYTEORDER_SWAB_H
- /*
- * linux/byteorder/swab.h
- * Byte-swapping, independently from CPU endianness
- * swabXX[ps]?(foo)
- *
- * Francois-Rene Rideau <fare@tunes.org> 19971205
- * separated swab functions from cpu_to_XX,
- * to clean up support for bizarre-endian architectures.
- *
- * See asm-i386/byteorder.h and suches for examples of how to provide
- * architecture-dependent optimized versions
- *
- */
- /* casts are necessary for constants, because we never know how for sure
- * how U/UL/ULL map to __u16, __u32, __u64. At least not in a portable way.
- */
- #define ___swab16(x)
- ({
- __u16 __x = (x);
- ((__u16)(
- (((__u16)(__x) & (__u16)0x00ffU) << 8) |
- (((__u16)(__x) & (__u16)0xff00U) >> 8) ));
- })
- #define ___swab32(x)
- ({
- __u32 __x = (x);
- ((__u32)(
- (((__u32)(__x) & (__u32)0x000000ffUL) << 24) |
- (((__u32)(__x) & (__u32)0x0000ff00UL) << 8) |
- (((__u32)(__x) & (__u32)0x00ff0000UL) >> 8) |
- (((__u32)(__x) & (__u32)0xff000000UL) >> 24) ));
- })
- #define ___swab64(x)
- ({
- __u64 __x = (x);
- ((__u64)(
- (__u64)(((__u64)(__x) & (__u64)0x00000000000000ffULL) << 56) |
- (__u64)(((__u64)(__x) & (__u64)0x000000000000ff00ULL) << 40) |
- (__u64)(((__u64)(__x) & (__u64)0x0000000000ff0000ULL) << 24) |
- (__u64)(((__u64)(__x) & (__u64)0x00000000ff000000ULL) << 8) |
- (__u64)(((__u64)(__x) & (__u64)0x000000ff00000000ULL) >> 8) |
- (__u64)(((__u64)(__x) & (__u64)0x0000ff0000000000ULL) >> 24) |
- (__u64)(((__u64)(__x) & (__u64)0x00ff000000000000ULL) >> 40) |
- (__u64)(((__u64)(__x) & (__u64)0xff00000000000000ULL) >> 56) ));
- })
- #define ___constant_swab16(x)
- ((__u16)(
- (((__u16)(x) & (__u16)0x00ffU) << 8) |
- (((__u16)(x) & (__u16)0xff00U) >> 8) ))
- #define ___constant_swab32(x)
- ((__u32)(
- (((__u32)(x) & (__u32)0x000000ffUL) << 24) |
- (((__u32)(x) & (__u32)0x0000ff00UL) << 8) |
- (((__u32)(x) & (__u32)0x00ff0000UL) >> 8) |
- (((__u32)(x) & (__u32)0xff000000UL) >> 24) ))
- #define ___constant_swab64(x)
- ((__u64)(
- (__u64)(((__u64)(x) & (__u64)0x00000000000000ffULL) << 56) |
- (__u64)(((__u64)(x) & (__u64)0x000000000000ff00ULL) << 40) |
- (__u64)(((__u64)(x) & (__u64)0x0000000000ff0000ULL) << 24) |
- (__u64)(((__u64)(x) & (__u64)0x00000000ff000000ULL) << 8) |
- (__u64)(((__u64)(x) & (__u64)0x000000ff00000000ULL) >> 8) |
- (__u64)(((__u64)(x) & (__u64)0x0000ff0000000000ULL) >> 24) |
- (__u64)(((__u64)(x) & (__u64)0x00ff000000000000ULL) >> 40) |
- (__u64)(((__u64)(x) & (__u64)0xff00000000000000ULL) >> 56) ))
- /*
- * provide defaults when no architecture-specific optimization is detected
- */
- #ifndef __arch__swab16
- # define __arch__swab16(x) ({ __u16 __tmp = (x) ; ___swab16(__tmp); })
- #endif
- #ifndef __arch__swab32
- # define __arch__swab32(x) ({ __u32 __tmp = (x) ; ___swab32(__tmp); })
- #endif
- #ifndef __arch__swab64
- # define __arch__swab64(x) ({ __u64 __tmp = (x) ; ___swab64(__tmp); })
- #endif
- #ifndef __arch__swab16p
- # define __arch__swab16p(x) __arch__swab16(*(x))
- #endif
- #ifndef __arch__swab32p
- # define __arch__swab32p(x) __arch__swab32(*(x))
- #endif
- #ifndef __arch__swab64p
- # define __arch__swab64p(x) __arch__swab64(*(x))
- #endif
- #ifndef __arch__swab16s
- # define __arch__swab16s(x) do { *(x) = __arch__swab16p((x)); } while (0)
- #endif
- #ifndef __arch__swab32s
- # define __arch__swab32s(x) do { *(x) = __arch__swab32p((x)); } while (0)
- #endif
- #ifndef __arch__swab64s
- # define __arch__swab64s(x) do { *(x) = __arch__swab64p((x)); } while (0)
- #endif
- /*
- * Allow constant folding
- */
- #if defined(__GNUC__) && (__GNUC__ >= 2) && defined(__OPTIMIZE__)
- # define __swab16(x)
- (__builtin_constant_p((__u16)(x)) ?
- ___swab16((x)) :
- __fswab16((x)))
- # define __swab32(x)
- (__builtin_constant_p((__u32)(x)) ?
- ___swab32((x)) :
- __fswab32((x)))
- # define __swab64(x)
- (__builtin_constant_p((__u64)(x)) ?
- ___swab64((x)) :
- __fswab64((x)))
- #else
- # define __swab16(x) __fswab16(x)
- # define __swab32(x) __fswab32(x)
- # define __swab64(x) __fswab64(x)
- #endif /* OPTIMIZE */
- static __inline__ __const__ __u16 __fswab16(__u16 x)
- {
- return __arch__swab16(x);
- }
- static __inline__ __u16 __swab16p(__u16 *x)
- {
- return __arch__swab16p(x);
- }
- static __inline__ void __swab16s(__u16 *addr)
- {
- __arch__swab16s(addr);
- }
- static __inline__ __const__ __u32 __fswab32(__u32 x)
- {
- return __arch__swab32(x);
- }
- static __inline__ __u32 __swab32p(__u32 *x)
- {
- return __arch__swab32p(x);
- }
- static __inline__ void __swab32s(__u32 *addr)
- {
- __arch__swab32s(addr);
- }
- #ifdef __BYTEORDER_HAS_U64__
- static __inline__ __const__ __u64 __fswab64(__u64 x)
- {
- # ifdef __SWAB_64_THRU_32__
- __u32 h = x >> 32;
- __u32 l = x & ((1ULL<<32)-1);
- return (((__u64)__swab32(l)) << 32) | ((__u64)(__swab32(h)));
- # else
- return __arch__swab64(x);
- # endif
- }
- static __inline__ __u64 __swab64p(__u64 *x)
- {
- return __arch__swab64p(x);
- }
- static __inline__ void __swab64s(__u64 *addr)
- {
- __arch__swab64s(addr);
- }
- #endif /* __BYTEORDER_HAS_U64__ */
- #if defined(__KERNEL__)
- #define swab16 __swab16
- #define swab32 __swab32
- #define swab64 __swab64
- #define swab16p __swab16p
- #define swab32p __swab32p
- #define swab64p __swab64p
- #define swab16s __swab16s
- #define swab32s __swab32s
- #define swab64s __swab64s
- #endif
- #endif /* _LINUX_BYTEORDER_SWAB_H */
