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Edit File: swab.h
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ #ifndef _LINUX_SWAB_H #define _LINUX_SWAB_H #include <linux/types.h> #include <asm/bitsperlong.h> #include <asm/swab.h> /* * 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 ___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)(x) & (__u64)0x00000000000000ffULL) << 56) | \ (((__u64)(x) & (__u64)0x000000000000ff00ULL) << 40) | \ (((__u64)(x) & (__u64)0x0000000000ff0000ULL) << 24) | \ (((__u64)(x) & (__u64)0x00000000ff000000ULL) << 8) | \ (((__u64)(x) & (__u64)0x000000ff00000000ULL) >> 8) | \ (((__u64)(x) & (__u64)0x0000ff0000000000ULL) >> 24) | \ (((__u64)(x) & (__u64)0x00ff000000000000ULL) >> 40) | \ (((__u64)(x) & (__u64)0xff00000000000000ULL) >> 56))) #define ___constant_swahw32(x) ((__u32)( \ (((__u32)(x) & (__u32)0x0000ffffUL) << 16) | \ (((__u32)(x) & (__u32)0xffff0000UL) >> 16))) #define ___constant_swahb32(x) ((__u32)( \ (((__u32)(x) & (__u32)0x00ff00ffUL) << 8) | \ (((__u32)(x) & (__u32)0xff00ff00UL) >> 8))) /* * Implement the following as inlines, but define the interface using * macros to allow constant folding when possible: * ___swab16, ___swab32, ___swab64, ___swahw32, ___swahb32 */ static __inline__ __u16 __fswab16(__u16 val) { #if defined (__arch_swab16) return __arch_swab16(val); #else return ___constant_swab16(val); #endif } static __inline__ __u32 __fswab32(__u32 val) { #if defined(__arch_swab32) return __arch_swab32(val); #else return ___constant_swab32(val); #endif } static __inline__ __u64 __fswab64(__u64 val) { #if defined (__arch_swab64) return __arch_swab64(val); #elif defined(__SWAB_64_THRU_32__) __u32 h = val >> 32; __u32 l = val & ((1ULL << 32) - 1); return (((__u64)__fswab32(l)) << 32) | ((__u64)(__fswab32(h))); #else return ___constant_swab64(val); #endif } static __inline__ __u32 __fswahw32(__u32 val) { #ifdef __arch_swahw32 return __arch_swahw32(val); #else return ___constant_swahw32(val); #endif } static __inline__ __u32 __fswahb32(__u32 val) { #ifdef __arch_swahb32 return __arch_swahb32(val); #else return ___constant_swahb32(val); #endif } /** * __swab16 - return a byteswapped 16-bit value * @x: value to byteswap */ #ifdef __HAVE_BUILTIN_BSWAP16__ #define __swab16(x) (__u16)__builtin_bswap16((__u16)(x)) #else #define __swab16(x) \ (__builtin_constant_p((__u16)(x)) ? \ ___constant_swab16(x) : \ __fswab16(x)) #endif /** * __swab32 - return a byteswapped 32-bit value * @x: value to byteswap */ #ifdef __HAVE_BUILTIN_BSWAP32__ #define __swab32(x) (__u32)__builtin_bswap32((__u32)(x)) #else #define __swab32(x) \ (__builtin_constant_p((__u32)(x)) ? \ ___constant_swab32(x) : \ __fswab32(x)) #endif /** * __swab64 - return a byteswapped 64-bit value * @x: value to byteswap */ #ifdef __HAVE_BUILTIN_BSWAP64__ #define __swab64(x) (__u64)__builtin_bswap64((__u64)(x)) #else #define __swab64(x) \ (__builtin_constant_p((__u64)(x)) ? \ ___constant_swab64(x) : \ __fswab64(x)) #endif static __always_inline unsigned long __swab(const unsigned long y) { #if __BITS_PER_LONG == 64 return __swab64(y); #else /* __BITS_PER_LONG == 32 */ return __swab32(y); #endif } /** * __swahw32 - return a word-swapped 32-bit value * @x: value to wordswap * * __swahw32(0x12340000) is 0x00001234 */ #define __swahw32(x) \ (__builtin_constant_p((__u32)(x)) ? \ ___constant_swahw32(x) : \ __fswahw32(x)) /** * __swahb32 - return a high and low byte-swapped 32-bit value * @x: value to byteswap * * __swahb32(0x12345678) is 0x34127856 */ #define __swahb32(x) \ (__builtin_constant_p((__u32)(x)) ? \ ___constant_swahb32(x) : \ __fswahb32(x)) /** * __swab16p - return a byteswapped 16-bit value from a pointer * @p: pointer to a naturally-aligned 16-bit value */ static __always_inline __u16 __swab16p(const __u16 *p) { #ifdef __arch_swab16p return __arch_swab16p(p); #else return __swab16(*p); #endif } /** * __swab32p - return a byteswapped 32-bit value from a pointer * @p: pointer to a naturally-aligned 32-bit value */ static __always_inline __u32 __swab32p(const __u32 *p) { #ifdef __arch_swab32p return __arch_swab32p(p); #else return __swab32(*p); #endif } /** * __swab64p - return a byteswapped 64-bit value from a pointer * @p: pointer to a naturally-aligned 64-bit value */ static __always_inline __u64 __swab64p(const __u64 *p) { #ifdef __arch_swab64p return __arch_swab64p(p); #else return __swab64(*p); #endif } /** * __swahw32p - return a wordswapped 32-bit value from a pointer * @p: pointer to a naturally-aligned 32-bit value * * See __swahw32() for details of wordswapping. */ static __inline__ __u32 __swahw32p(const __u32 *p) { #ifdef __arch_swahw32p return __arch_swahw32p(p); #else return __swahw32(*p); #endif } /** * __swahb32p - return a high and low byteswapped 32-bit value from a pointer * @p: pointer to a naturally-aligned 32-bit value * * See __swahb32() for details of high/low byteswapping. */ static __inline__ __u32 __swahb32p(const __u32 *p) { #ifdef __arch_swahb32p return __arch_swahb32p(p); #else return __swahb32(*p); #endif } /** * __swab16s - byteswap a 16-bit value in-place * @p: pointer to a naturally-aligned 16-bit value */ static __inline__ void __swab16s(__u16 *p) { #ifdef __arch_swab16s __arch_swab16s(p); #else *p = __swab16p(p); #endif } /** * __swab32s - byteswap a 32-bit value in-place * @p: pointer to a naturally-aligned 32-bit value */ static __always_inline void __swab32s(__u32 *p) { #ifdef __arch_swab32s __arch_swab32s(p); #else *p = __swab32p(p); #endif } /** * __swab64s - byteswap a 64-bit value in-place * @p: pointer to a naturally-aligned 64-bit value */ static __always_inline void __swab64s(__u64 *p) { #ifdef __arch_swab64s __arch_swab64s(p); #else *p = __swab64p(p); #endif } /** * __swahw32s - wordswap a 32-bit value in-place * @p: pointer to a naturally-aligned 32-bit value * * See __swahw32() for details of wordswapping */ static __inline__ void __swahw32s(__u32 *p) { #ifdef __arch_swahw32s __arch_swahw32s(p); #else *p = __swahw32p(p); #endif } /** * __swahb32s - high and low byteswap a 32-bit value in-place * @p: pointer to a naturally-aligned 32-bit value * * See __swahb32() for details of high and low byte swapping */ static __inline__ void __swahb32s(__u32 *p) { #ifdef __arch_swahb32s __arch_swahb32s(p); #else *p = __swahb32p(p); #endif } #endif /* _LINUX_SWAB_H */