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/*
* Let's make sure we always have a sane definition for ntohl()/htonl().
* Some libraries define those as a function call, just to perform byte
* shifting, bringing significant overhead to what should be a simple
* operation.
*/
/*
* Default version that the compiler ought to optimize properly with
* constant values.
*/
static inline uint32_t default_swab32(uint32_t val)
{
return (((val & 0xff000000) >> 24) |
((val & 0x00ff0000) >> 8) |
((val & 0x0000ff00) << 8) |
((val & 0x000000ff) << 24));
}
#if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
#define bswap32(x) ({ \
uint32_t __res; \
if (__builtin_constant_p(x)) { \
__res = default_swab32(x); \
} else { \
__asm__("bswap %0" : "=r" (__res) : "0" (x)); \
} \
__res; })
#undef ntohl
#undef htonl
#define ntohl(x) bswap32(x)
#define htonl(x) bswap32(x)
#endif
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