src/core/common/offset_range.cpp

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/**
 * @file
 *   This file implements helper method for an offset range.
 */

#include "offset_range.hpp"

#include "common/code_utils.hpp"
#include "common/message.hpp"
#include "common/num_utils.hpp"
#include "common/numeric_limits.hpp"

namespace ot {

void OffsetRange::Init(uint16_t aOffset, uint16_t aLength)
{
    uint16_t maxLength = NumericLimits<uint16_t>::kMax - aOffset;

    mOffset = aOffset;
    mLength = Min(aLength, maxLength);
}

void OffsetRange::InitFromRange(uint16_t aStartOffset, uint16_t aEndOffset)
{
    Init(aStartOffset, Max(aStartOffset, aEndOffset) - aStartOffset);
}

void OffsetRange::InitFromMessageOffsetToEnd(const Message &aMessage)
{
    InitFromRange(aMessage.GetOffset(), aMessage.GetLength());
}

void OffsetRange::InitFromMessageFullLength(const Message &aMessage) { Init(0, aMessage.GetLength()); }

void OffsetRange::AdvanceOffset(uint32_t aLength)
{
    uint16_t length = static_cast<uint16_t>(Min<uint32_t>(aLength, mLength));

    mOffset += length;
    mLength -= length;
}

void OffsetRange::ShrinkLength(uint16_t aLength) { mLength = Min(mLength, aLength); }

} // namespace ot