// 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 <stdint.h> #include "third_party/base/logging.h" #include "third_party/build/build_config.h" #if defined(COMPILER_MSVC) #include <stdlib.h> #endif namespace pdfium { namespace base { // Returns a value with all bytes in |x| swapped, i.e. reverses the endianness. inline uint16_t ByteSwap(uint16_t x) { #if defined(COMPILER_MSVC) return _byteswap_ushort(x); #else return __builtin_bswap16(x); #endif } inline uint32_t ByteSwap(uint32_t x) { #if defined(COMPILER_MSVC) return _byteswap_ulong(x); #else return __builtin_bswap32(x); #endif } inline uint64_t ByteSwap(uint64_t x) { #if defined(COMPILER_MSVC) return _byteswap_uint64(x); #else return __builtin_bswap64(x); #endif } inline uintptr_t ByteSwapUintPtrT(uintptr_t x) { // We do it this way because some build configurations are ILP32 even when // defined(ARCH_CPU_64_BITS). Unfortunately, we can't use sizeof in #ifs. But, // because these conditionals are constexprs, the irrelevant branches will // likely be optimized away, so this construction should not result in code // bloat. if (sizeof(uintptr_t) == 4) { return ByteSwap(static_cast<uint32_t>(x)); } else if (sizeof(uintptr_t) == 8) { return ByteSwap(static_cast<uint64_t>(x)); } else { NOTREACHED(); } } // 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 base } // namespace pdfium #endif // BASE_SYS_BYTEORDER_H_