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/* Copyright 2014 Jozsef Kadlecsik (kadlec@blackhole.kfki.hu)
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#ifndef LIBIPSET_COMPAT_H
#define LIBIPSET_COMPAT_H

#ifndef be64toh

#include <endian.h>
/* Swap bytes in 64 bit value.  */
#if __BYTE_ORDER == __LITTLE_ENDIAN
/* From bits/byteswap.h in eglibc source: */
#define __bswap_constant_32(x) \
     ((((x) & 0xff000000u) >> 24) | (((x) & 0x00ff0000u) >>  8) |	      \
      (((x) & 0x0000ff00u) <<  8) | (((x) & 0x000000ffu) << 24))

#ifdef __GNUC__
# define __bswap_32(x) \
  (__extension__							      \
   ({ register unsigned int __bsx = (x); __bswap_constant_32 (__bsx); }))
#else
static __inline unsigned int
__bswap_32 (unsigned int __bsx)
{
  return __bswap_constant_32 (__bsx);
}
#endif

#if defined __GNUC__ && __GNUC__ >= 2
/* Swap bytes in 64 bit value.  */
# define __bswap_constant_64(x) \
     ((((x) & 0xff00000000000000ull) >> 56)				      \
      | (((x) & 0x00ff000000000000ull) >> 40)				      \
      | (((x) & 0x0000ff0000000000ull) >> 24)				      \
      | (((x) & 0x000000ff00000000ull) >> 8)				      \
      | (((x) & 0x00000000ff000000ull) << 8)				      \
      | (((x) & 0x0000000000ff0000ull) << 24)				      \
      | (((x) & 0x000000000000ff00ull) << 40)				      \
      | (((x) & 0x00000000000000ffull) << 56))

# define __bswap_64(x) \
     (__extension__							      \
      ({ union { __extension__ unsigned long long int __ll;		      \
		 unsigned int __l[2]; } __w, __r;			      \
         if (__builtin_constant_p (x))					      \
	   __r.__ll = __bswap_constant_64 (x);				      \
	 else								      \
	   {								      \
	     __w.__ll = (x);						      \
	     __r.__l[0] = __bswap_32 (__w.__l[1]);			      \
	     __r.__l[1] = __bswap_32 (__w.__l[0]);			      \
	   }								      \
	 __r.__ll; }))
#else
#error "Unsupported, you need at least gcc 3.x"
#endif

#define be64toh(x) __bswap_64(x)
#define htobe64(x) __bswap_64(x)
#else
#define be64toh(x) (x)
#define htobe64(x) (x)
#endif

#endif

#endif /* LIBIPSET_COMPAT_H */