tlvs.hpp

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#ifndef TLVS_HPP_
#define TLVS_HPP_

#include "openthread-core-config.h"

#include "utils/wrap_string.h"

#include <openthread/types.h>

#include "common/encoding.hpp"
#include "common/message.hpp"

using ot::Encoding::BigEndian::HostSwap16;
using ot::Encoding::BigEndian::HostSwap32;

namespace ot {

OT_TOOL_PACKED_BEGIN
class Tlv
{
public:
    Tlv(void):
        mType(0),
        mLength(0) {}

    uint8_t GetType(void) const { return mType; }

    void SetType(uint8_t aType) { mType = aType; }

    uint8_t GetLength(void) const { return mLength; }

    void SetLength(uint8_t aLength) { mLength = aLength; }

    uint8_t GetSize(void) const { return sizeof(Tlv) + mLength; }

    uint8_t *GetValue(void) { return reinterpret_cast<uint8_t *>(this) + sizeof(Tlv); }

    const uint8_t *GetValue(void) const { return reinterpret_cast<const uint8_t *>(this) + sizeof(Tlv); }

    Tlv *GetNext(void) {
        return reinterpret_cast<Tlv *>(reinterpret_cast<uint8_t *>(this) + sizeof(*this) + mLength);
    }

    const Tlv *GetNext(void) const {
        return reinterpret_cast<const Tlv *>(reinterpret_cast<const uint8_t *>(this) + sizeof(*this) + mLength);
    }

    static otError Get(const Message &aMessage, uint8_t aType, uint16_t aMaxLength, Tlv &aTlv);

    static otError GetOffset(const Message &aMessage, uint8_t aType, uint16_t &aOffset);

    static otError GetValueOffset(const Message &aMesasge, uint8_t aType, uint16_t &aOffset, uint16_t &aLength);

protected:
    enum
    {
        kExtendedLength = 255, 
    };

private:
    uint8_t mType;
    uint8_t mLength;
} OT_TOOL_PACKED_END;

OT_TOOL_PACKED_BEGIN
class ExtendedTlv: public Tlv
{
public:
    uint16_t GetLength(void) const { return HostSwap16(mLength); }

    void SetLength(uint16_t aLength) { Tlv::SetLength(kExtendedLength); mLength = HostSwap16(aLength); }

private:
    uint16_t mLength;
} OT_TOOL_PACKED_END;

}  // namespace ot

#endif  // TLVS_HPP_