src/core/thread/network_data_tlvs.cpp

/*
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 *     derived from this software without specific prior written permission.
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/**
 * @file
 *   This file implements methods for generating and processing Thread Network Data TLVs.
 */

#include "network_data_tlvs.hpp"

namespace ot {
namespace NetworkData {

//---------------------------------------------------------------------------------------------------------------------
// NetworkDataTlv

const NetworkDataTlv *NetworkDataTlv::Find(const NetworkDataTlv *aStart, const NetworkDataTlv *aEnd, Type aType)
{
    const NetworkDataTlv *tlv;

    for (tlv = aStart; (tlv + 1 <= aEnd) && (tlv->GetNext() <= aEnd); tlv = tlv->GetNext())
    {
        if (tlv->GetType() == aType)
        {
            ExitNow();
        }
    }

    tlv = nullptr;

exit:
    return tlv;
}

const NetworkDataTlv *NetworkDataTlv::Find(const NetworkDataTlv *aStart,
                                           const NetworkDataTlv *aEnd,
                                           Type                  aType,
                                           bool                  aStable)
{
    const NetworkDataTlv *tlv;

    for (tlv = aStart; (tlv + 1 <= aEnd) && (tlv->GetNext() <= aEnd); tlv = tlv->GetNext())
    {
        if ((tlv->GetType() == aType) && (tlv->IsStable() == aStable))
        {
            ExitNow();
        }
    }

    tlv = nullptr;

exit:
    return tlv;
}

//---------------------------------------------------------------------------------------------------------------------
// PrefixTlv

const NetworkDataTlv *PrefixTlv::FindSubTlv(Type aType) const
{
    return Find(GetSubTlvs(), GetNext(), aType);
}

const NetworkDataTlv *PrefixTlv::FindSubTlv(Type aType, bool aStable) const
{
    return Find(GetSubTlvs(), GetNext(), aType, aStable);
}

//---------------------------------------------------------------------------------------------------------------------
// ServiceTlv

void ServiceTlv::Init(uint8_t aServiceId, uint32_t aEnterpriseNumber, const ServiceData &aServiceData)
{
    NetworkDataTlv::Init();
    SetType(kTypeService);

    mFlagsServiceId = (aEnterpriseNumber == kThreadEnterpriseNumber) ? kThreadEnterpriseFlag : 0;
    mFlagsServiceId |= (aServiceId & kServiceIdMask);

    if (aEnterpriseNumber != kThreadEnterpriseNumber)
    {
        mShared.mEnterpriseNumber = HostSwap32(aEnterpriseNumber);
        mServiceDataLength        = aServiceData.GetLength();
        aServiceData.CopyBytesTo(&mServiceDataLength + sizeof(uint8_t));
    }
    else
    {
        mShared.mServiceDataLengthThreadEnterprise = aServiceData.GetLength();
        aServiceData.CopyBytesTo(&mShared.mServiceDataLengthThreadEnterprise + sizeof(uint8_t));
    }

    SetLength(GetFieldsLength());
}

//---------------------------------------------------------------------------------------------------------------------
// TlvIterator

const NetworkDataTlv *TlvIterator::Iterate(NetworkDataTlv::Type aType)
{
    const NetworkDataTlv *tlv = NetworkDataTlv::Find(mStart, mEnd, aType);

    VerifyOrExit(tlv != nullptr);
    mStart = tlv->GetNext();

exit:
    return tlv;
}

const NetworkDataTlv *TlvIterator::Iterate(NetworkDataTlv::Type aType, bool aStable)
{
    const NetworkDataTlv *tlv = NetworkDataTlv::Find(mStart, mEnd, aType, aStable);

    VerifyOrExit(tlv != nullptr);
    mStart = tlv->GetNext();

exit:
    return tlv;
}

} // namespace NetworkData
} // namespace ot