| // 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 BASE_SYS_BYTEORDER_H_ |
| #define BASE_SYS_BYTEORDER_H_ |
| |
| #include "base/basictypes.h" |
| #include "build/build_config.h" |
| |
| #if defined(OS_WIN) |
| #include <winsock2.h> |
| #else |
| #include <arpa/inet.h> |
| #endif |
| |
| namespace base { |
| |
| // Returns a value with all bytes in |x| swapped, i.e. reverses the endianness. |
| inline uint16 ByteSwap(uint16 x) { |
| return ((x & 0x00ff) << 8) | ((x & 0xff00) >> 8); |
| } |
| |
| inline uint32 ByteSwap(uint32 x) { |
| return ((x & 0x000000fful) << 24) | ((x & 0x0000ff00ul) << 8) | |
| ((x & 0x00ff0000ul) >> 8) | ((x & 0xff000000ul) >> 24); |
| } |
| |
| inline uint64 ByteSwap(uint64 x) { |
| return ((x & 0x00000000000000ffull) << 56) | |
| ((x & 0x000000000000ff00ull) << 40) | |
| ((x & 0x0000000000ff0000ull) << 24) | |
| ((x & 0x00000000ff000000ull) << 8) | |
| ((x & 0x000000ff00000000ull) >> 8) | |
| ((x & 0x0000ff0000000000ull) >> 24) | |
| ((x & 0x00ff000000000000ull) >> 40) | |
| ((x & 0xff00000000000000ull) >> 56); |
| } |
| |
| // Converts the bytes in |x| from host order (endianness) to little endian, and |
| // returns the result. |
| inline uint16 ByteSwapToLE16(uint16 x) { |
| #if defined(ARCH_CPU_LITTLE_ENDIAN) |
| return x; |
| #else |
| return ByteSwap(x); |
| #endif |
| } |
| inline uint32 ByteSwapToLE32(uint32 x) { |
| #if defined(ARCH_CPU_LITTLE_ENDIAN) |
| return x; |
| #else |
| return ByteSwap(x); |
| #endif |
| } |
| inline uint64 ByteSwapToLE64(uint64 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 NetToHost16(uint16 x) { |
| #if defined(ARCH_CPU_LITTLE_ENDIAN) |
| return ByteSwap(x); |
| #else |
| return x; |
| #endif |
| } |
| inline uint32 NetToHost32(uint32 x) { |
| #if defined(ARCH_CPU_LITTLE_ENDIAN) |
| return ByteSwap(x); |
| #else |
| return x; |
| #endif |
| } |
| inline uint64 NetToHost64(uint64 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 HostToNet16(uint16 x) { |
| #if defined(ARCH_CPU_LITTLE_ENDIAN) |
| return ByteSwap(x); |
| #else |
| return x; |
| #endif |
| } |
| inline uint32 HostToNet32(uint32 x) { |
| #if defined(ARCH_CPU_LITTLE_ENDIAN) |
| return ByteSwap(x); |
| #else |
| return x; |
| #endif |
| } |
| inline uint64 HostToNet64(uint64 x) { |
| #if defined(ARCH_CPU_LITTLE_ENDIAN) |
| return ByteSwap(x); |
| #else |
| return x; |
| #endif |
| } |
| |
| } // namespace base |
| |
| #endif // BASE_SYS_BYTEORDER_H_ |