| /* |
| * Copyright (c) 2016, The OpenThread Authors. |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * 3. Neither the name of the copyright holder nor the |
| * names of its contributors may be used to endorse or promote products |
| * derived from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE |
| * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| * POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| /** |
| * @file |
| * This file includes definitions for byte-ordering encoding. |
| */ |
| |
| #ifndef ENCODING_HPP_ |
| #define ENCODING_HPP_ |
| |
| #include "openthread-core-config.h" |
| |
| #ifndef BYTE_ORDER_BIG_ENDIAN |
| #if defined(WORDS_BIGENDIAN) || \ |
| defined(__BYTE_ORDER__) && defined(__ORDER_BIG_ENDIAN__) && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__ |
| #define BYTE_ORDER_BIG_ENDIAN 1 |
| #else |
| #define BYTE_ORDER_BIG_ENDIAN 0 |
| #endif |
| #endif |
| |
| #include <limits.h> |
| #include <stdint.h> |
| |
| namespace ot { |
| namespace Encoding { |
| |
| inline uint16_t Swap16(uint16_t v) |
| { |
| return (((v & 0x00ffU) << 8) & 0xff00) | (((v & 0xff00U) >> 8) & 0x00ff); |
| } |
| |
| inline uint32_t Swap32(uint32_t v) |
| { |
| return ((v & static_cast<uint32_t>(0x000000ffUL)) << 24) | ((v & static_cast<uint32_t>(0x0000ff00UL)) << 8) | |
| ((v & static_cast<uint32_t>(0x00ff0000UL)) >> 8) | ((v & static_cast<uint32_t>(0xff000000UL)) >> 24); |
| } |
| |
| inline uint64_t Swap64(uint64_t v) |
| { |
| return ((v & static_cast<uint64_t>(0x00000000000000ffULL)) << 56) | |
| ((v & static_cast<uint64_t>(0x000000000000ff00ULL)) << 40) | |
| ((v & static_cast<uint64_t>(0x0000000000ff0000ULL)) << 24) | |
| ((v & static_cast<uint64_t>(0x00000000ff000000ULL)) << 8) | |
| ((v & static_cast<uint64_t>(0x000000ff00000000ULL)) >> 8) | |
| ((v & static_cast<uint64_t>(0x0000ff0000000000ULL)) >> 24) | |
| ((v & static_cast<uint64_t>(0x00ff000000000000ULL)) >> 40) | |
| ((v & static_cast<uint64_t>(0xff00000000000000ULL)) >> 56); |
| } |
| |
| inline uint32_t Reverse32(uint32_t v) |
| { |
| v = ((v & 0x55555555) << 1) | ((v & 0xaaaaaaaa) >> 1); |
| v = ((v & 0x33333333) << 2) | ((v & 0xcccccccc) >> 2); |
| v = ((v & 0x0f0f0f0f) << 4) | ((v & 0xf0f0f0f0) >> 4); |
| v = ((v & 0x00ff00ff) << 8) | ((v & 0xff00ff00) >> 8); |
| v = ((v & 0x0000ffff) << 16) | ((v & 0xffff0000) >> 16); |
| |
| return v; |
| } |
| |
| #define BitVectorBytes(x) static_cast<uint8_t>(((x) + (CHAR_BIT - 1)) / CHAR_BIT) |
| |
| namespace BigEndian { |
| |
| #if BYTE_ORDER_BIG_ENDIAN |
| |
| inline uint16_t HostSwap16(uint16_t v) |
| { |
| return v; |
| } |
| inline uint32_t HostSwap32(uint32_t v) |
| { |
| return v; |
| } |
| inline uint64_t HostSwap64(uint64_t v) |
| { |
| return v; |
| } |
| |
| #else /* BYTE_ORDER_LITTLE_ENDIAN */ |
| |
| inline uint16_t HostSwap16(uint16_t v) |
| { |
| return Swap16(v); |
| } |
| inline uint32_t HostSwap32(uint32_t v) |
| { |
| return Swap32(v); |
| } |
| inline uint64_t HostSwap64(uint64_t v) |
| { |
| return Swap64(v); |
| } |
| |
| #endif // LITTLE_ENDIAN |
| |
| /** |
| * This template function performs host swap on a given unsigned integer value assuming big-endian encoding. |
| * |
| * @tparam UintType The unsigned int type. |
| * |
| * @param aValue The value to host swap. |
| * |
| * @returns The host swapped value. |
| * |
| */ |
| template <typename UintType> UintType HostSwap(UintType aValue); |
| |
| template <> inline uint8_t HostSwap(uint8_t aValue) |
| { |
| return aValue; |
| } |
| template <> inline uint16_t HostSwap(uint16_t aValue) |
| { |
| return HostSwap16(aValue); |
| } |
| template <> inline uint32_t HostSwap(uint32_t aValue) |
| { |
| return HostSwap32(aValue); |
| } |
| template <> inline uint64_t HostSwap(uint64_t aValue) |
| { |
| return HostSwap64(aValue); |
| } |
| |
| /** |
| * This function reads a `uint16_t` value from a given buffer assuming big-endian encoding. |
| * |
| * @param[in] aBuffer Pointer to buffer to read from. |
| * |
| * @returns The `uint16_t` value read from buffer. |
| * |
| */ |
| inline uint16_t ReadUint16(const uint8_t *aBuffer) |
| { |
| return static_cast<uint16_t>((aBuffer[0] << 8) | aBuffer[1]); |
| } |
| |
| /** |
| * This function reads a `uint32_t` value from a given buffer assuming big-endian encoding. |
| * |
| * @param[in] aBuffer Pointer to buffer to read from. |
| * |
| * @returns The `uint32_t` value read from buffer. |
| * |
| */ |
| inline uint32_t ReadUint32(const uint8_t *aBuffer) |
| { |
| return ((static_cast<uint32_t>(aBuffer[0]) << 24) | (static_cast<uint32_t>(aBuffer[1]) << 16) | |
| (static_cast<uint32_t>(aBuffer[2]) << 8) | (static_cast<uint32_t>(aBuffer[3]) << 0)); |
| } |
| |
| /** |
| * This function reads a 24-bit integer value from a given buffer assuming big-endian encoding. |
| * |
| * @param[in] aBuffer Pointer to buffer to read from. |
| * |
| * @returns The value read from buffer. |
| * |
| */ |
| inline uint32_t ReadUint24(const uint8_t *aBuffer) |
| { |
| return ((static_cast<uint32_t>(aBuffer[0]) << 16) | (static_cast<uint32_t>(aBuffer[1]) << 8) | |
| (static_cast<uint32_t>(aBuffer[2]) << 0)); |
| } |
| |
| /** |
| * This function reads a `uint64_t` value from a given buffer assuming big-endian encoding. |
| * |
| * @param[in] aBuffer Pointer to buffer to read from. |
| * |
| * @returns The `uint64_t` value read from buffer. |
| * |
| */ |
| inline uint64_t ReadUint64(const uint8_t *aBuffer) |
| { |
| return ((static_cast<uint64_t>(aBuffer[0]) << 56) | (static_cast<uint64_t>(aBuffer[1]) << 48) | |
| (static_cast<uint64_t>(aBuffer[2]) << 40) | (static_cast<uint64_t>(aBuffer[3]) << 32) | |
| (static_cast<uint64_t>(aBuffer[4]) << 24) | (static_cast<uint64_t>(aBuffer[5]) << 16) | |
| (static_cast<uint64_t>(aBuffer[6]) << 8) | (static_cast<uint64_t>(aBuffer[7]) << 0)); |
| } |
| |
| /** |
| * This function writes a `uint16_t` value to a given buffer using big-endian encoding. |
| * |
| * @param[in] aValue The value to write to buffer. |
| * @param[out] aBuffer Pointer to buffer where the value will be written. |
| * |
| */ |
| inline void WriteUint16(uint16_t aValue, uint8_t *aBuffer) |
| { |
| aBuffer[0] = (aValue >> 8) & 0xff; |
| aBuffer[1] = (aValue >> 0) & 0xff; |
| } |
| |
| /** |
| * This function writes a 24-bit integer value to a given buffer using big-endian encoding. |
| * |
| * @param[in] aValue The value to write to buffer. |
| * @param[out] aBuffer Pointer to buffer where the value will be written. |
| * |
| */ |
| inline void WriteUint24(uint32_t aValue, uint8_t *aBuffer) |
| { |
| aBuffer[0] = (aValue >> 16) & 0xff; |
| aBuffer[1] = (aValue >> 8) & 0xff; |
| aBuffer[2] = (aValue >> 0) & 0xff; |
| } |
| |
| /** |
| * This function writes a `uint32_t` value to a given buffer using big-endian encoding. |
| * |
| * @param[in] aValue The value to write to buffer. |
| * @param[out] aBuffer Pointer to buffer where the value will be written. |
| * |
| */ |
| inline void WriteUint32(uint32_t aValue, uint8_t *aBuffer) |
| { |
| aBuffer[0] = (aValue >> 24) & 0xff; |
| aBuffer[1] = (aValue >> 16) & 0xff; |
| aBuffer[2] = (aValue >> 8) & 0xff; |
| aBuffer[3] = (aValue >> 0) & 0xff; |
| } |
| |
| /** |
| * This function writes a `uint64_t` value to a given buffer using big-endian encoding. |
| * |
| * @param[in] aValue The value to write to buffer. |
| * @param[out] aBuffer Pointer to buffer where the value will be written. |
| * |
| */ |
| inline void WriteUint64(uint64_t aValue, uint8_t *aBuffer) |
| { |
| aBuffer[0] = (aValue >> 56) & 0xff; |
| aBuffer[1] = (aValue >> 48) & 0xff; |
| aBuffer[2] = (aValue >> 40) & 0xff; |
| aBuffer[3] = (aValue >> 32) & 0xff; |
| aBuffer[4] = (aValue >> 24) & 0xff; |
| aBuffer[5] = (aValue >> 16) & 0xff; |
| aBuffer[6] = (aValue >> 8) & 0xff; |
| aBuffer[7] = (aValue >> 0) & 0xff; |
| } |
| |
| } // namespace BigEndian |
| |
| namespace LittleEndian { |
| |
| #if BYTE_ORDER_BIG_ENDIAN |
| |
| inline uint16_t HostSwap16(uint16_t v) |
| { |
| return Swap16(v); |
| } |
| inline uint32_t HostSwap32(uint32_t v) |
| { |
| return Swap32(v); |
| } |
| inline uint64_t HostSwap64(uint64_t v) |
| { |
| return Swap64(v); |
| } |
| |
| #else /* BYTE_ORDER_LITTLE_ENDIAN */ |
| |
| inline uint16_t HostSwap16(uint16_t v) |
| { |
| return v; |
| } |
| inline uint32_t HostSwap32(uint32_t v) |
| { |
| return v; |
| } |
| inline uint64_t HostSwap64(uint64_t v) |
| { |
| return v; |
| } |
| |
| #endif |
| |
| /** |
| * This template function performs host swap on a given unsigned integer value assuming little-endian encoding. |
| * |
| * @tparam UintType The unsigned int type. |
| * |
| * @param aValue The value to host swap. |
| * |
| * @returns The host swapped value. |
| * |
| */ |
| template <typename UintType> UintType HostSwap(UintType aValue); |
| |
| template <> inline uint8_t HostSwap(uint8_t aValue) |
| { |
| return aValue; |
| } |
| template <> inline uint16_t HostSwap(uint16_t aValue) |
| { |
| return HostSwap16(aValue); |
| } |
| template <> inline uint32_t HostSwap(uint32_t aValue) |
| { |
| return HostSwap32(aValue); |
| } |
| template <> inline uint64_t HostSwap(uint64_t aValue) |
| { |
| return HostSwap64(aValue); |
| } |
| |
| /** |
| * This function reads a `uint16_t` value from a given buffer assuming little-endian encoding. |
| * |
| * @param[in] aBuffer Pointer to buffer to read from. |
| * |
| * @returns The `uint16_t` value read from buffer. |
| * |
| */ |
| inline uint16_t ReadUint16(const uint8_t *aBuffer) |
| { |
| return static_cast<uint16_t>(aBuffer[0] | (aBuffer[1] << 8)); |
| } |
| |
| /** |
| * This function reads a 24-bit integer value from a given buffer assuming little-endian encoding. |
| * |
| * @param[in] aBuffer Pointer to buffer to read from. |
| * |
| * @returns The value read from buffer. |
| * |
| */ |
| inline uint32_t ReadUint24(const uint8_t *aBuffer) |
| { |
| return ((static_cast<uint32_t>(aBuffer[0]) << 0) | (static_cast<uint32_t>(aBuffer[1]) << 8) | |
| (static_cast<uint32_t>(aBuffer[2]) << 16)); |
| } |
| |
| /** |
| * This function reads a `uint32_t` value from a given buffer assuming little-endian encoding. |
| * |
| * @param[in] aBuffer Pointer to buffer to read from. |
| * |
| * @returns The `uint32_t` value read from buffer. |
| * |
| */ |
| inline uint32_t ReadUint32(const uint8_t *aBuffer) |
| { |
| return ((static_cast<uint32_t>(aBuffer[0]) << 0) | (static_cast<uint32_t>(aBuffer[1]) << 8) | |
| (static_cast<uint32_t>(aBuffer[2]) << 16) | (static_cast<uint32_t>(aBuffer[3]) << 24)); |
| } |
| |
| /** |
| * This function reads a `uint64_t` value from a given buffer assuming little-endian encoding. |
| * |
| * @param[in] aBuffer Pointer to buffer to read from. |
| * |
| * @returns The `uint64_t` value read from buffer. |
| * |
| */ |
| inline uint64_t ReadUint64(const uint8_t *aBuffer) |
| { |
| return ((static_cast<uint64_t>(aBuffer[0]) << 0) | (static_cast<uint64_t>(aBuffer[1]) << 8) | |
| (static_cast<uint64_t>(aBuffer[2]) << 16) | (static_cast<uint64_t>(aBuffer[3]) << 24) | |
| (static_cast<uint64_t>(aBuffer[4]) << 32) | (static_cast<uint64_t>(aBuffer[5]) << 40) | |
| (static_cast<uint64_t>(aBuffer[6]) << 48) | (static_cast<uint64_t>(aBuffer[7]) << 56)); |
| } |
| |
| /** |
| * This function writes a `uint16_t` value to a given buffer using little-endian encoding. |
| * |
| * @param[in] aValue The value to write to buffer. |
| * @param[out] aBuffer Pointer to buffer where the value will be written. |
| * |
| */ |
| inline void WriteUint16(uint16_t aValue, uint8_t *aBuffer) |
| { |
| aBuffer[0] = (aValue >> 0) & 0xff; |
| aBuffer[1] = (aValue >> 8) & 0xff; |
| } |
| |
| /** |
| * This function writes a 24-bit integer value to a given buffer using little-endian encoding. |
| * |
| * @param[in] aValue The value to write to buffer. |
| * @param[out] aBuffer Pointer to buffer where the value will be written. |
| * |
| */ |
| inline void WriteUint24(uint32_t aValue, uint8_t *aBuffer) |
| { |
| aBuffer[0] = (aValue >> 0) & 0xff; |
| aBuffer[1] = (aValue >> 8) & 0xff; |
| aBuffer[2] = (aValue >> 16) & 0xff; |
| } |
| |
| /** |
| * This function writes a `uint32_t` value to a given buffer using little-endian encoding. |
| * |
| * @param[in] aValue The value to write to buffer. |
| * @param[out] aBuffer Pointer to buffer where the value will be written. |
| * |
| */ |
| inline void WriteUint32(uint32_t aValue, uint8_t *aBuffer) |
| { |
| aBuffer[0] = (aValue >> 0) & 0xff; |
| aBuffer[1] = (aValue >> 8) & 0xff; |
| aBuffer[2] = (aValue >> 16) & 0xff; |
| aBuffer[3] = (aValue >> 24) & 0xff; |
| } |
| |
| /** |
| * This function writes a `uint64_t` value to a given buffer using little-endian encoding. |
| * |
| * @param[in] aValue The value to write to buffer. |
| * @param[out] aBuffer Pointer to buffer where the value will be written. |
| * |
| */ |
| inline void WriteUint64(uint64_t aValue, uint8_t *aBuffer) |
| { |
| aBuffer[0] = (aValue >> 0) & 0xff; |
| aBuffer[1] = (aValue >> 8) & 0xff; |
| aBuffer[2] = (aValue >> 16) & 0xff; |
| aBuffer[3] = (aValue >> 24) & 0xff; |
| aBuffer[4] = (aValue >> 32) & 0xff; |
| aBuffer[5] = (aValue >> 40) & 0xff; |
| aBuffer[6] = (aValue >> 48) & 0xff; |
| aBuffer[7] = (aValue >> 56) & 0xff; |
| } |
| |
| } // namespace LittleEndian |
| } // namespace Encoding |
| } // namespace ot |
| |
| #endif // ENCODING_HPP_ |