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hex.h

#ifndef CRYPTOPP_HEX_H
#define CRYPTOPP_HEX_H

#include "cryptlib.h"
#include "filters.h"

NAMESPACE_BEGIN(CryptoPP)

class HexEncoder : public Filter
{
public:
        HexEncoder(BufferedTransformation *outQueue = NULL, bool uppercase = true);

        void Put(byte inByte)
        {
                AttachedTransformation()->Put(m_vec[inByte >> 4]);
                AttachedTransformation()->Put(m_vec[inByte & 0x0F]);
        }

        void Put(const byte *inString, unsigned int length);

private:
        const byte *m_vec;
};

class HexDecoder : public Filter
{
public:
        HexDecoder(BufferedTransformation *outQueue = NULL)
                : Filter(outQueue) {last = -1;}

        void Put(byte inByte)
        {
                int i=ConvToNumber(inByte);
                if (i >= 0)
                {
                        if (last >= 0)
                        {
                                AttachedTransformation()->Put((last << 4) | i);
                                last = -1;
                        }
                        else
                                last = i;
                }
        }

        void Put(const byte *inString, unsigned int length);

        void MessageEnd(int propagate=-1);

private:
        static int ConvToNumber(byte inByte)
        {
                if (inByte >= '0' && inByte <= '9')
                        return inByte - '0';
                if (inByte >= 'A' && inByte <= 'F')
                        return inByte - 'A' + 10;
                if (inByte >= 'a' && inByte <= 'f')
                        return inByte - 'a' + 10;
                return -1;
        }

        int last;
};

NAMESPACE_END

#endif

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