| // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| // This header defines cross-platform ByteSwap() implementations for 16, 32 and |
| // 64-bit values, and NetToHostXX() / HostToNextXX() functions equivalent to |
| // the traditional ntohX() and htonX() functions. |
| // Use the functions defined here rather than using the platform-specific |
| // functions directly. |
| |
| #ifndef BUTIL_SYS_BYTEORDER_H_ |
| #define BUTIL_SYS_BYTEORDER_H_ |
| |
| #include "butil/basictypes.h" |
| #include "butil/build_config.h" |
| |
| #if defined(OS_WIN) |
| #include <winsock2.h> |
| #else |
| #include <arpa/inet.h> |
| #endif |
| |
| #if defined(COMPILER_MSVC) |
| #include <stdlib.h> // for _byteswap_* |
| #elif defined(OS_MACOSX) |
| // Mac OS X / Darwin features |
| #include <libkern/OSByteOrder.h> // for OSSwapInt* |
| #elif defined(OS_LINUX) |
| #include <byteswap.h> // for bswap_* |
| #endif |
| |
| namespace butil { |
| |
| #if defined(COMPILER_MSVC) |
| inline uint16_t ByteSwap(uint16_t x) { return _byteswap_ushort(x); } |
| inline uint32_t ByteSwap(uint32_t x) { return _byteswap_ulong(x); } |
| inline uint64_t ByteSwap(uint64_t x) { return _byteswap_uint64(x); } |
| |
| #elif defined(OS_MACOSX) |
| inline uint16_t ByteSwap(uint16_t x) { return OSSwapInt16(x); } |
| inline uint32_t ByteSwap(uint32_t x) { return OSSwapInt32(x); } |
| inline uint64_t ByteSwap(uint64_t x) { return OSSwapInt64(x); } |
| |
| #elif defined(OS_LINUX) |
| inline uint16_t ByteSwap(uint16_t x) { return bswap_16(x); } |
| inline uint32_t ByteSwap(uint32_t x) { return bswap_32(x); } |
| inline uint64_t ByteSwap(uint64_t x) { return bswap_64(x); } |
| |
| #else |
| // Returns a value with all bytes in |x| swapped, i.e. reverses the endianness. |
| inline uint16_t ByteSwap(uint16_t x) { |
| return (x << 8) | (x >> 8); |
| } |
| |
| inline uint32_t ByteSwap(uint32_t x) { |
| x = ((x & 0xff00ff00UL) >> 8) | ((x & 0x00ff00ffUL) << 8); |
| return (x >> 16) | (x << 16); |
| } |
| |
| inline uint64_t ByteSwap(uint64_t x) { |
| x = ((x & 0xff00ff00ff00ff00ULL) >> 8) | ((x & 0x00ff00ff00ff00ffULL) << 8); |
| x = ((x & 0xffff0000ffff0000ULL) >> 16) | ((x & 0x0000ffff0000ffffULL) << 16); |
| return (x >> 32) | (x << 32); |
| } |
| #endif |
| |
| // Converts the bytes in |x| from host order (endianness) to little endian, and |
| // returns the result. |
| inline uint16_t ByteSwapToLE16(uint16_t x) { |
| #if defined(ARCH_CPU_LITTLE_ENDIAN) |
| return x; |
| #else |
| return ByteSwap(x); |
| #endif |
| } |
| inline uint32_t ByteSwapToLE32(uint32_t x) { |
| #if defined(ARCH_CPU_LITTLE_ENDIAN) |
| return x; |
| #else |
| return ByteSwap(x); |
| #endif |
| } |
| inline uint64_t ByteSwapToLE64(uint64_t x) { |
| #if defined(ARCH_CPU_LITTLE_ENDIAN) |
| return x; |
| #else |
| return ByteSwap(x); |
| #endif |
| } |
| |
| // Converts the bytes in |x| from network to host order (endianness), and |
| // returns the result. |
| inline uint16_t NetToHost16(uint16_t x) { |
| #if defined(ARCH_CPU_LITTLE_ENDIAN) |
| return ByteSwap(x); |
| #else |
| return x; |
| #endif |
| } |
| inline uint32_t NetToHost32(uint32_t x) { |
| #if defined(ARCH_CPU_LITTLE_ENDIAN) |
| return ByteSwap(x); |
| #else |
| return x; |
| #endif |
| } |
| inline uint64_t NetToHost64(uint64_t x) { |
| #if defined(ARCH_CPU_LITTLE_ENDIAN) |
| return ByteSwap(x); |
| #else |
| return x; |
| #endif |
| } |
| |
| // Converts the bytes in |x| from host to network order (endianness), and |
| // returns the result. |
| inline uint16_t HostToNet16(uint16_t x) { |
| #if defined(ARCH_CPU_LITTLE_ENDIAN) |
| return ByteSwap(x); |
| #else |
| return x; |
| #endif |
| } |
| inline uint32_t HostToNet32(uint32_t x) { |
| #if defined(ARCH_CPU_LITTLE_ENDIAN) |
| return ByteSwap(x); |
| #else |
| return x; |
| #endif |
| } |
| inline uint64_t HostToNet64(uint64_t x) { |
| #if defined(ARCH_CPU_LITTLE_ENDIAN) |
| return ByteSwap(x); |
| #else |
| return x; |
| #endif |
| } |
| |
| } // namespace butil |
| |
| #endif // BUTIL_SYS_BYTEORDER_H_ |