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++ // Copyright (C) 2021 The Qt Company Ltd.
++ // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
++ // Qt-Security score:significant reason:default
++
++ #ifndef QMODBUSADU_P_H
++ #define QMODBUSADU_P_H
++
++ #include <QtSerialBus/qmodbuspdu.h>
++ #include <QtCore/private/qglobal_p.h>
++
++ //
++ // W A R N I N G
++ // -------------
++ //
++ // This file is not part of the Qt API. It exists purely as an
++ // implementation detail. This header file may change from version to
++ // version without notice, or even be removed.
++ //
++ // We mean it.
++ //
++
++ QT_BEGIN_NAMESPACE
++
++ class QModbusSerialAdu
++ {
++ public:
++ enum Type {
++ Ascii,
++ Rtu
++ };
++
++ inline QModbusSerialAdu(Type type, const QByteArray &data)
++ : m_type(type), m_data(data), m_rawData(data)
++ {
++ if (m_type == Ascii)
++ m_data = QByteArray::fromHex(m_data.mid(1, m_data.size() - 3));
++ }
++
++ inline int size() const {
++ if (m_type == Ascii)
++ return m_data.size() - 1; // one byte, LRC
++ return m_data.size() - 2; // two bytes, CRC
++ }
++ inline QByteArray data() const { return m_data.left(size()); }
++
++ inline int rawSize() const { return m_rawData.size(); }
++ inline QByteArray rawData() const { return m_rawData; }
++
++ inline int serverAddress() const {
++ Q_ASSERT_X(!m_data.isEmpty(), "QModbusAdu::serverAddress()", "Empty ADU.");
++ return quint8(m_data.at(0));
++ }
++
++ inline QModbusPdu pdu() const {
++ Q_ASSERT_X(m_data.size() >= 2, "QModbusAdu::pdu()", "Not enough bytes in ADU.");
++ return QModbusPdu(QModbusPdu::FunctionCode(m_data.at(1)), m_data.mid(2, size() - 2));
++ }
++
++ template <typename T>
++ auto checksum() const -> decltype(T()) {
++ if (m_type == Ascii) {
++ Q_ASSERT_X(!m_data.isEmpty(), "QModbusAdu::checksum()", "Empty ADU.");
++ return quint8(m_data[m_data.size() - 1]);
++ }
++ Q_ASSERT_X(m_data.size() >= 2, "QModbusAdu::checksum()",
++ "Not enough bytes to calculate checksum.");
++ return quint16(quint8(m_data[m_data.size() - 2]) << 8 | quint8(m_data[m_data.size() - 1]));
++ }
++
++ inline bool matchingChecksum() const {
++ Q_ASSERT_X(!m_data.isEmpty(), "QModbusAdu::matchingChecksum()", "Empty ADU.");
++ if (m_type == Ascii)
++ return QModbusSerialAdu::calculateLRC(data(), size()) == checksum<quint8>();
++ return QModbusSerialAdu::calculateCRC(data(), size()) == checksum<quint16>();
++ }
++
++ /*!
++ \internal
++ \fn quint8 QModbusSerialAdu::calculateLRC(const char *data, qint32 len)
++
++ Returns the LRC checksum of the first \a len bytes of \a data. The checksum is independent
++ of the byte order (endianness).
++ */
++ inline static quint8 calculateLRC(const char *data, qint32 len)
++ {
++ quint32 lrc = 0;
++ while (len--)
++ lrc += *data++;
++ return -(quint8(lrc));
++ }
++
++ /*!
++ \internal
++ \fn quint16 QModbusSerialAdu::calculateCRC(const char *data, qint32 len) const
++
++ Returns the CRC checksum of the first \a len bytes of \a data.
++
++ \note The code used by the function was generated with pycrc. There is no copyright assigned
++ to the generated code, however, the author of the script requests to show the line stating
++ that the code was generated by pycrc (see implementation).
++ */
++ inline static quint16 calculateCRC(const char *data, qint32 len)
++ {
++ // Generated by pycrc v0.8.3, https://pycrc.org
++ // Width = 16, Poly = 0x8005, XorIn = 0xffff, ReflectIn = True,
++ // XorOut = 0x0000, ReflectOut = True, Algorithm = bit-by-bit-fast
++
++ quint16 crc = 0xFFFF;
++ while (len--) {
++ const quint8 c = *data++;
++ for (qint32 i = 0x01; i & 0xFF; i <<= 1) {
++ bool bit = crc & 0x8000;
++ if (c & i)
++ bit = !bit;
++ crc <<= 1;
++ if (bit)
++ crc ^= 0x8005;
++ }
++ crc &= 0xFFFF;
++ }
++ crc = crc_reflect(crc & 0xFFFF, 16) ^ 0x0000;
++ return (crc >> 8) | (crc << 8); // swap bytes
++ }
++
++ inline static QByteArray create(Type type, int serverAddress, const QModbusPdu &pdu,
++ char delimiter = '\n') {
++ QByteArray result;
++ QDataStream out(&result, QIODevice::WriteOnly);
++ out << quint8(serverAddress) << pdu;
++
++ if (type == Ascii) {
++ out << calculateLRC(result, result.size());
++ return ":" + result.toHex() + "\r" + delimiter;
++ } else {
++ out << calculateCRC(result, result.size());
++ }
++ return result;
++ }
++
++ private:
++ inline static quint16 crc_reflect(quint16 data, qint32 len)
++ {
++ // Generated by pycrc v0.8.3, https://pycrc.org
++ // Width = 16, Poly = 0x8005, XorIn = 0xffff, ReflectIn = True,
++ // XorOut = 0x0000, ReflectOut = True, Algorithm = bit-by-bit-fast
++
++ quint16 ret = data & 0x01;
++ for (qint32 i = 1; i < len; i++) {
++ data >>= 1;
++ ret = (ret << 1) | (data & 0x01);
++ }
++ return ret;
++ }
++
++ private:
++ Type m_type = Rtu;
++ QByteArray m_data;
++ QByteArray m_rawData;
++ };
++
++ QT_END_NAMESPACE
++
++ #endif // QMODBUSADU_P_H