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#pragma once
#include <cstdint>
namespace blobs
{
using std::size_t;
using std::uint16_t;
using std::uint32_t;
using std::uint8_t;
constexpr uint16_t crc16Ccitt = 0x1021;
/* Value from: http://srecord.sourceforge.net/crc16-ccitt.html for
* implementation without explicit bit adding.
*/
constexpr uint16_t crc16Initial = 0xFFFF;
class CrcInterface
{
public:
virtual ~CrcInterface() = default;
/**
* Reset the crc.
*/
virtual void clear() = 0;
/**
* Provide bytes against which to compute the crc. This method is
* meant to be only called once between clear() and get().
*
* @param[in] bytes - the data against which to compute.
* @param[in] length - the number of bytes.
*/
virtual void compute(const uint8_t* bytes, uint32_t length) = 0;
/**
* Read back the current crc value.
*
* @return the crc16 value.
*/
virtual uint16_t get() const = 0;
};
class Crc16 : public CrcInterface
{
public:
Crc16() : poly(crc16Ccitt), value(crc16Initial){};
~Crc16() = default;
void clear() override;
void compute(const uint8_t* bytes, uint32_t length) override;
uint16_t get() const override;
private:
uint16_t poly;
uint16_t value;
};
} // namespace blobs
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