hc_bswap32
int32_t hc_bswap32(int32_t var);
tmp.magic = hc_bswap32(tmp.magic);
tmp.bytes = hc_bswap32(tmp.bytes);
tmp.error = hc_bswap32(tmp.error);
item->bytes = hc_bswap32(item->bytes);
*i32ptr = hc_bswap32(*i32ptr);
return (hc_bswap32(var >> 32 & 0xffffffff)
| (int64_t) hc_bswap32(var & 0xffffffff) << 32);