/* * 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 such 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. */ #ifndef _SWAB_H #define _SWAB_H #include <stdint.h> #if ENV_ARMV4 #define swab16(x) \ ((unsigned short)( \ (((unsigned short)(x) & (unsigned short)0x00ffU) << 8) | \ (((unsigned short)(x) & (unsigned short)0xff00U) >> 8))) #define swab32(x) \ ((unsigned int)( \ (((unsigned int)(x) & 0x000000ffUL) << 24) | \ (((unsigned int)(x) & 0x0000ff00UL) << 8) | \ (((unsigned int)(x) & 0x00ff0000UL) >> 8) | \ (((unsigned int)(x) & 0xff000000UL) >> 24))) #define swab64(x) \ ((uint64_t)( \ (((uint64_t)(x) & (uint64_t)0x00000000000000ffULL) << 56) | \ (((uint64_t)(x) & (uint64_t)0x000000000000ff00ULL) << 40) | \ (((uint64_t)(x) & (uint64_t)0x0000000000ff0000ULL) << 24) | \ (((uint64_t)(x) & (uint64_t)0x00000000ff000000ULL) << 8) | \ (((uint64_t)(x) & (uint64_t)0x000000ff00000000ULL) >> 8) | \ (((uint64_t)(x) & (uint64_t)0x0000ff0000000000ULL) >> 24) | \ (((uint64_t)(x) & (uint64_t)0x00ff000000000000ULL) >> 40) | \ (((uint64_t)(x) & (uint64_t)0xff00000000000000ULL) >> 56))) #else /* ENV_ARMV4 */ #define swab16(x) ((uint16_t)__builtin_bswap16(x)) #define swab32(x) ((uint32_t)__builtin_bswap32(x)) #define swab64(x) ((uint64_t)__builtin_bswap64(x)) #endif /* !ENV_ARMV4 */ #endif /* _SWAB_H */