gmio/src/gmio_core/internal/byte_codec.h

/****************************************************************************
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#ifndef GMIO_INTERNAL_BYTE_CODEC_H
#define GMIO_INTERNAL_BYTE_CODEC_H

#include "../global.h"

/*! Reads a 16bit integer from memory-location \p bytes (little-endian) */
GMIO_INLINE uint16_t gmio_decode_uint16_le(const uint8_t* bytes)
{
    /* |0 |1 | */
    /* |BB|AA| -> 0xAABB */
    return (bytes[1] << 8) | bytes[0];
}

/*! Reads a 16bit integer from memory-location \p bytes (big-endian) */
GMIO_INLINE uint16_t gmio_decode_uint16_be(const uint8_t* bytes)
{
    /* |0 |1 | */
    /* |AA|BB| -> 0xAABB */
    return (bytes[0] << 8) | bytes[1];
}

/*! Writes 16bit integer \p val to the memory location at \p bytes in
 *  little-endian */
GMIO_INLINE void gmio_encode_uint16_le(uint16_t val, uint8_t* bytes)
{
    bytes[0] = val & 0xFF;
    bytes[1] = (val >> 8) & 0xFF;
}

/*! Reads a 32bit integer from memory-location \p bytes (little-endian) */
GMIO_INLINE uint32_t gmio_decode_uint32_le(const uint8_t* bytes)
{
    /* |DD|CC|BB|AA| -> 0xAABBCCDD */
    return bytes[0] | (bytes[1] << 8) | (bytes[2] << 16) | (bytes[3] << 24);
}

/*! Reads a 32bit integer from memory-location \p bytes (mixed-endian) */
GMIO_INLINE uint32_t gmio_decode_uint32_me(const uint8_t* bytes)
{
    /* |DD|CC|BB|AA| -> 0xCCDDAABB */
    return (bytes[0] << 16) | (bytes[1] << 24) | (bytes[3] << 8) | bytes[2];
}

/*! Reads a 32bit integer from memory-location \p bytes (big-endian) */
GMIO_INLINE uint32_t gmio_decode_uint32_be(const uint8_t* bytes)
{
    /* |DD|CC|BB|AA| -> 0xDDCCBBAA */
    return bytes[3] | (bytes[2] << 8) | (bytes[1] << 16) | (bytes[0] << 24);
}

/*! Writes 32bit integer \p val to the memory location at \p bytes in
 *  little-endian */
GMIO_INLINE void gmio_encode_uint32_le(uint32_t val, uint8_t* bytes)
{
    bytes[0] = val & 0xFF;
    bytes[1] = (val >> 8) & 0xFF;
    bytes[2] = (val >> 16) & 0xFF;
    bytes[3] = (val >> 24) & 0xFF;
}

/*! Writes 32bit integer \p val to the memory location at \p bytes in
 *  big-endian */
GMIO_INLINE void gmio_encode_uint32_be(uint32_t val, uint8_t* bytes)
{
    bytes[0] = (val >> 24) & 0xFF;
    bytes[1] = (val >> 16) & 0xFF;
    bytes[2] = (val >> 8) & 0xFF;
    bytes[3] = val & 0xFF;
}

#endif /* GMIO_INTERNAL_BYTE_CODEC_H */