xref: /aosp_15_r20/external/openthread/src/lib/utils/endian.hpp (revision cfb92d1480a9e65faed56933e9c12405f45898b4)

/*
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 *     documentation and/or other materials provided with the distribution.
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 *     names of its contributors may be used to endorse or promote products
 *     derived from this software without specific prior written permission.
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 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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/**
 * @file
 *   This file includes definitions for endianness utility functions.
 */

#ifndef LIB_UTILS_ENDIAN_HPP_
#define LIB_UTILS_ENDIAN_HPP_

#include <stdint.h>

namespace ot {
namespace Lib {
namespace Utils {

namespace LittleEndian {
/**
 * 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)); }

/**
 * 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;
}

} // namespace LittleEndian
} // namespace Utils
} // namespace Lib
} // namespace ot

#endif // LIB_UTILS_ENDIAN_HPP_