src/core/common/appender.cpp

/*
 *  Copyright (c) 2021, The OpenThread Authors.
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 *     names of its contributors may be used to endorse or promote products
 *     derived from this software without specific prior written permission.
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 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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/**
 * @file
 *   This file implements the `Appender` class.
 */

#include "appender.hpp"

namespace ot {

Appender::Appender(Message &aMessage)
    : mType(kMessage)
{
    mShared.mMessage.mMessage     = &aMessage;
    mShared.mMessage.mStartOffset = aMessage.GetLength();
}

Appender::Appender(uint8_t *aBuffer, uint16_t aSize)
    : mType(kBuffer)
{
    mShared.mFrameBuilder.Init(aBuffer, aSize);
}

Error Appender::AppendBytes(const void *aBuffer, uint16_t aLength)
{
    Error error = kErrorNone;

    switch (mType)
    {
    case kMessage:
        error = mShared.mMessage.mMessage->AppendBytes(aBuffer, aLength);
        break;

    case kBuffer:
        error = mShared.mFrameBuilder.AppendBytes(aBuffer, aLength);
        break;
    }

    return error;
}

uint16_t Appender::GetAppendedLength(void) const
{
    uint16_t length = 0;

    switch (mType)
    {
    case kMessage:
        length = mShared.mMessage.mMessage->GetLength() - mShared.mMessage.mStartOffset;
        break;

    case kBuffer:
        length = mShared.mFrameBuilder.GetLength();
        break;
    }

    return length;
}

void Appender::GetAsData(Data<kWithUint16Length> &aData) const
{
    aData.Init(mShared.mFrameBuilder.GetBytes(), mShared.mFrameBuilder.GetLength());
}

} // namespace ot