| /* |
| * 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)); |
| } |
| |
| #undef bswap32 |
| |
| #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" ((uint32_t)(x))); \ |
| } \ |
| __res; }) |
| |
| #elif defined(_MSC_VER) && (defined(_M_IX86) || defined(_M_X64)) |
| |
| #include <stdlib.h> |
| |
| #define bswap32(x) _byteswap_ulong(x) |
| |
| #endif |
| |
| #ifdef bswap32 |
| |
| #undef ntohl |
| #undef htonl |
| #define ntohl(x) bswap32(x) |
| #define htonl(x) bswap32(x) |
| |
| #endif |