#ifndef _LINUX_BYTEORDER_SWABB_H #define _LINUX_BYTEORDER_SWABB_H /* * linux/byteorder/swabb.h * SWAp Bytes Bizarrely * swaHHXX[ps]?(foo) * * Support for obNUXIous pdp-endian and other bizarre architectures. * Will Linux ever run on such ancient beasts? if not, this file * will be but a programming pearl. Still, it's a reminder that we * shouldn't be making too many assumptions when trying to be portable. * */ /* * Meaning of the names I chose (vaxlinux people feel free to correct them): * swahw32 swap 16-bit half-words in a 32-bit word * swahb32 swap 8-bit halves of each 16-bit half-word in a 32-bit word * * No 64-bit support yet. I don't know NUXI conventions for long longs. * I guarantee it will be a mess when it's there, though :-> * It will be even worse if there are conflicting 64-bit conventions. * Hopefully, no one ever used 64-bit objects on NUXI machines. * */ #define ___swahw32(x) \ ((__u32)( \ (((__u32)(x) & (__u32)0x0000ffffUL) << 16) | \ (((__u32)(x) & (__u32)0xffff0000UL) >> 16) )) #define ___swahb32(x) \ ((__u32)( \ (((__u32)(x) & (__u32)0x00ff00ffUL) << 8) | \ (((__u32)(x) & (__u32)0xff00ff00UL) >> 8) )) /* * provide defaults when no architecture-specific optimization is detected */ #ifndef __arch__swahw32 # define __arch__swahw32(x) ___swahw32(x) #endif #ifndef __arch__swahb32 # define __arch__swahb32(x) ___swahb32(x) #endif #ifndef __arch__swahw32p # define __arch__swahw32p(x) __swahw32(*(x)) #endif #ifndef __arch__swahb32p # define __arch__swahb32p(x) __swahb32(*(x)) #endif #ifndef __arch__swahw32s # define __arch__swahw32s(x) do { *(x) = __swahw32p((x)); } while (0) #endif #ifndef __arch__swahb32s # define __arch__swahb32s(x) do { *(x) = __swahb32p((x)); } while (0) #endif /* * Allow constant folding */ #if defined(__GNUC__) && (__GNUC__ >= 2) && defined(__OPTIMIZE__) # define __swahw32(x) \ (__builtin_constant_p((__u32)(x)) ? \ ___swahw32((x)) : \ __fswahw32((x))) # define __swahb32(x) \ (__builtin_constant_p((__u32)(x)) ? \ ___swahb32((x)) : \ __fswahb32((x))) #else # define __swahw32(x) __fswahw32(x) # define __swahb32(x) __fswahb32(x) #endif /* OPTIMIZE */ extern __inline__ __const__ __u32 __fswahw32(__u32 x) { return __arch__swahw32(x); } extern __inline__ __u32 __swahw32p(__u32 *x) { return __arch__swahw32p(x); } extern __inline__ void __swahw32s(__u32 *addr) { __arch__swahw32s(addr); } extern __inline__ __const__ __u32 __fswahb32(__u32 x) { return __arch__swahb32(x); } extern __inline__ __u32 __swahb32p(__u32 *x) { return __arch__swahb32p(x); } extern __inline__ void __swahb32s(__u32 *addr) { __arch__swahb32s(addr); } #ifdef __BYTEORDER_HAS_U64__ /* * Not supported yet */ #endif /* __BYTEORDER_HAS_U64__ */ #if defined(__KERNEL__) #define swahw32 __swahw32 #define swahb32 __swahb32 #define swahw32p __swahw32p #define swahb32p __swahb32p #define swahw32s __swahw32s #define swahb32s __swahb32s #endif #endif /* _LINUX_BYTEORDER_SWABB_H */