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/*      $NetBSD: bswap.h,v 1.19 2015/03/12 15:28:16 christos Exp $      */
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/* Written by Manuel Bouyer. Public domain */
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#ifndef _SYS_BSWAP_H_
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#define _SYS_BSWAP_H_
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#ifndef _LOCORE
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#include <sys/stdint.h>
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#include <machine/bswap.h>
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__BEGIN_DECLS
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/* Always declare the functions in case their address is taken (etc) */
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#if defined(_KERNEL) || defined(_STANDALONE) || !defined(__BSWAP_RENAME)
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uint16_t bswap16(uint16_t) __constfunc;
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uint32_t bswap32(uint32_t) __constfunc;
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#else
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uint16_t bswap16(uint16_t) __RENAME(__bswap16) __constfunc;
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uint32_t bswap32(uint32_t) __RENAME(__bswap32) __constfunc;
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#endif
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uint64_t bswap64(uint64_t) __constfunc;
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__END_DECLS
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#if defined(__GNUC__) && !defined(__lint__)
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/* machine/byte_swap.h might have defined inline versions */
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#ifndef __BYTE_SWAP_U64_VARIABLE
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#define        __BYTE_SWAP_U64_VARIABLE bswap64
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#endif
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#ifndef __BYTE_SWAP_U32_VARIABLE
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#define        __BYTE_SWAP_U32_VARIABLE bswap32
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#endif
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#ifndef __BYTE_SWAP_U16_VARIABLE
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#define        __BYTE_SWAP_U16_VARIABLE bswap16
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#endif
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#define        __byte_swap_u64_constant(x) \
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        (__CAST(uint64_t, \
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         ((((x) & 0xff00000000000000ull) >> 56) | \
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          (((x) & 0x00ff000000000000ull) >> 40) | \
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          (((x) & 0x0000ff0000000000ull) >> 24) | \
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          (((x) & 0x000000ff00000000ull) >>  8) | \
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          (((x) & 0x00000000ff000000ull) <<  8) | \
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          (((x) & 0x0000000000ff0000ull) << 24) | \
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          (((x) & 0x000000000000ff00ull) << 40) | \
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          (((x) & 0x00000000000000ffull) << 56))))
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#define        __byte_swap_u32_constant(x) \
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        (__CAST(uint32_t, \
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        ((((x) & 0xff000000) >> 24) | \
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         (((x) & 0x00ff0000) >>  8) | \
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         (((x) & 0x0000ff00) <<  8) | \
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         (((x) & 0x000000ff) << 24))))
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#define        __byte_swap_u16_constant(x) \
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        (__CAST(uint16_t, \
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        ((((x) & 0xff00) >> 8) | \
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         (((x) & 0x00ff) << 8))))
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#define        bswap64(x) \
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        __CAST(uint64_t, __builtin_constant_p((x)) ? \
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         __byte_swap_u64_constant(x) : __BYTE_SWAP_U64_VARIABLE(x))
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#define        bswap32(x) \
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        __CAST(uint32_t, __builtin_constant_p((x)) ? \
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         __byte_swap_u32_constant(x) : __BYTE_SWAP_U32_VARIABLE(x))
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#define        bswap16(x) \
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        __CAST(uint16_t, __builtin_constant_p((x)) ? \
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         __byte_swap_u16_constant(x) : __BYTE_SWAP_U16_VARIABLE(x))
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#endif /* __GNUC__ && !__lint__ */
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#endif /* !_LOCORE */
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#endif /* !_SYS_BSWAP_H_ */