问如何在C ++中的big-endian和little-endian值之间进行转换？

EN

unsigned short _byteswap_ushort(unsigned short value);

unsigned long _byteswap_ulong(unsigned long value);

unsigned __int64 _byteswap_uint64(unsigned __int64 value);

int32_t __builtin_bswap32 (int32_t x)
int64_t __builtin_bswap64 (int64_t x)

#include <climits>

template <typename T>
T swap_endian(T u)
{
    static_assert (CHAR_BIT == 8, "CHAR_BIT != 8");

    union
    {
        T u;
        unsigned char u8[sizeof(T)];
    } source, dest;

    source.u = u;

    for (size_t k = 0; k < sizeof(T); k++)
        dest.u8[k] = source.u8[sizeof(T) - k - 1];

    return dest.u;
}