path: root/src/serialbus/qcanbusframe.cpp

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#include "qcanbusframe.h"

#include <QtCore/qdatastream.h>

QT_BEGIN_NAMESPACE

/*!
    \class QCanBusFrame
    \inmodule QtSerialBus
    \since 5.8

    \brief QCanBusFrame is a container class representing a single CAN frame.

    \l QCanBusDevice can use QCanBusFrame for read and write operations. It contains the frame
    identifier and the data payload. QCanBusFrame contains the timestamp of the moment it was read.

    \sa QCanBusFrame::TimeStamp
*/

/*!
    \fn QCanBusFrame::QCanBusFrame(QCanBusFrame::FrameType type = DataFrame)

    Constructs a CAN frame of the specified \a type.
*/

/*!
    \fn QCanBusFrame::QCanBusFrame(quint32 identifier, const QByteArray &data)

    Constructs a CAN frame using \a identifier as the frame identifier and \a data as the payload.
*/

/*!
    \fn bool QCanBusFrame::isValid() const

    Returns \c false if the \l frameType() is \l InvalidFrame,
    the \l hasExtendedFrameFormat() is not set although \l frameId() is longer than 11 bit or
    the payload is longer than the maximal permitted payload length of 64 byte if \e {Flexible
    Data-Rate} mode is enabled or 8 byte if it is disabled. If \l frameType() is \l RemoteRequestFrame
    and the \e {Flexible Data-Rate} mode is enabled at the same time \c false is also returned.

    Otherwise this function returns \c true.
*/

/*!
    \fn QCanBusFrame::setFrameId(quint32 newFrameId)

    Sets the identifier of the CAN frame to \a newFrameId. The maximum size of a CAN frame
    identifier is 11 bits, which can be extended up to 29 bits by supporting the \e {CAN extended frame
    format}. The \e {CAN extended frame format} setting is automatically adapted to match \a newFrameId.

    \sa frameId(), hasExtendedFrameFormat()
*/

/*!
    \fn QCanBusFrame::setPayload(const QByteArray &data)

    Sets \a data as the payload for the CAN frame. The maximum size of payload is 8 bytes, which can
    be extended up to 64 bytes by supporting \e {Flexible Data-Rate}. If \a data contains more than
    8 byte the \e {Flexible Data-Rate} flag is automatically set. Flexible Data-Rate has to be
    enabled on the \l QCanBusDevice by setting the \l QCanBusDevice::CanFdKey.

    Frames of type \l RemoteRequestFrame (RTR) do not have a payload. However they have to
    provide an indication of the responses expected payload length. To set the length expection it
    is necessary to set a fake payload whose length matches the expected payload length of the
    response. One way of doing this might be as follows:

    \code
        QCanBusFrame frame(QCanBusFrame::RemoteRequestFrame);
        int expectedResponseLength = ...;
        frame.setPayload(QByteArray(expectedResponseLength, 0));
    \endcode

    \sa payload(), hasFlexibleDataRateFormat()
*/

/*!
    \fn QCanBusFrame::setTimeStamp(TimeStamp ts)

    Sets \a ts as the timestamp for the CAN frame. Usually, this function is not needed, because the
    timestamp is created during the read operation and not needed during the write operation.

    \sa QCanBusFrame::TimeStamp
*/

/*!
    \fn quint32 QCanBusFrame::frameId() const

    Returns the CAN frame identifier. If the CAN frame uses the
    extended frame format, the identifier has a maximum of 29 bits;
    otherwise 11 bits.

    If the frame is of \l ErrorFrame type, this ID is always 0.

    \sa setFrameId(), hasExtendedFrameFormat()
*/

/*!
    \fn bool QCanBusFrame::hasExtendedFrameFormat() const

    Returns \c true if the CAN frame uses a 29bit identifier;
    otherwise \c false, implying an 11bit identifier.

    \sa setExtendedFrameFormat(), frameId()
*/

/*!
    \fn  void QCanBusFrame::setExtendedFrameFormat(bool isExtended)

    Sets the extended frame format flag to \a isExtended.

    \sa hasExtendedFrameFormat()
*/

/*!
    \enum QCanBusFrame::Version
    \internal

    This enum describes the version of the QCanBusFrame.

    With newer Qt versions, new features may be added to QCanBusFrame. To support serializing and
    deserializing of frames with different features, the version needs to be incremented every
    time a new feature appears. This enum describes, at which Qt version a specific QCanBusFrame
    version appeared.

    \value Qt_5_8               This frame is the initial version introduced in Qt 5.8
    \value Qt_5_9               This frame version was introduced in Qt 5.9
*/

/*!
    \enum QCanBusFrame::FrameType

    This enum describes the type of the CAN frame.

    \value UnknownFrame         The frame type is unknown.
    \value DataFrame            This value represents a data frame.
    \value ErrorFrame           This value represents an error frame.
    \value RemoteRequestFrame   This value represents a remote request.
    \value InvalidFrame         This value represents an invalid frame.
                                This type is used for error reporting.

    \sa setFrameType()
*/

/*!
    \enum QCanBusFrame::FrameError

    This enum describes the possible error types.

    \value NoError                      No error has occurred.
    \value TransmissionTimeoutError     The transmission has timed out.
    \value LostArbitrationError         The frame could not be sent due to lost
                                        arbitration on the bus.
    \value ControllerError              The controller encountered an error.
    \value ProtocolViolationError       A protocol violation has occurred.
    \value TransceiverError             A transceiver error occurred
    \value MissingAcknowledgmentError   The transmission received no
                                        acknowledgment.
    \value BusOffError                  The CAN bus is offline.
    \value BusError                     A CAN bus error occurred.
    \value ControllerRestartError       The controller restarted.
    \value UnknownError                 An unknown error has occurred.
    \value AnyError                     Matches every other error type.
*/

/*!
    \fn FrameType QCanBusFrame::frameType() const

    Returns the type of the frame.

    \sa setFrameType()
*/

/*!
    \fn void QCanBusFrame::setFrameType(FrameType newType)

    Sets the type of the frame to \a newType.

    \sa frameType()
*/

/*!
    \fn QByteArray QCanBusFrame::payload() const

    Returns the data payload of the frame.

    \sa setPayload()
*/

/*!
    \fn TimeStamp QCanBusFrame::timeStamp() const

    Returns the timestamp of the frame.

    \sa QCanBusFrame::TimeStamp, QCanBusFrame::setTimeStamp()
*/

/*!
    \fn FrameErrors QCanBusFrame::error() const

    Returns the error of the current error frame. If the frame
    is not an \l ErrorFrame, this function returns \l NoError.

    \sa setError()
*/

/*!
    \fn void QCanBusFrame::setError(FrameErrors error)

    Sets the frame's \a error type. This function does nothing if
    \l frameType() is not an \l ErrorFrame.

    \sa error()
*/

/*!
    \fn bool QCanBusFrame::hasFlexibleDataRateFormat() const

    Returns \c true if the CAN frame uses \e {Flexible Data-Rate} which allows up to 64 data bytes,
    otherwise \c false, implying at most 8 byte of payload.

    \sa setFlexibleDataRateFormat(), payload()
*/

/*!
    \fn  void QCanBusFrame::setFlexibleDataRateFormat(bool isFlexibleData)

    Sets the \e {Flexible Data-Rate} flag to \a isFlexibleData. Those frames can be sent using
    a higher speed on supporting controllers. Additionally the payload length limit is raised to
    64 byte.

    \sa hasFlexibleDataRateFormat()
*/

/*!
    \fn QCanBusFrame::hasBitrateSwitch() const
    \since 5.9

    Returns \c true if the CAN uses \e {Flexible Data-Rate} with \e {Bitrate Switch},
    to transfer the payload data at a higher data bitrate.

    \sa setBitrateSwitch() QCanBusDevice::DataBitRateKey
*/

/*!
    \fn void QCanBusFrame::setBitrateSwitch(bool bitrateSwitch)
    \since 5.9

    Set the \e {Flexible Data-Rate} flag \e {Bitrate Switch} flag to \a bitrateSwitch.
    The data field of frames with this flag is transferred at a higher data bitrate.

    \sa hasBitrateSwitch() QCanBusDevice::DataBitRateKey
*/

/*!
    \fn QCanBusFrame::hasErrorStateIndicator() const
    \since 5.9

    Returns \c true if the CAN uses \e {Flexible Data-Rate} with \e {Error State Indicator} set.

    This flag is set by the transmitter's CAN FD hardware to indicate the transmitter's error state.

    \sa setErrorStateIndicator()
*/

/*!
    \fn void QCanBusFrame::setErrorStateIndicator(bool errorStateIndicator)
    \since 5.9

    Set the \e {Flexible Data-Rate} flag \e {Error State Indicator} flag to \a errorStateIndicator.

    When sending CAN FD frames, this flag is automatically set by the CAN FD hardware.
    \c QCanBusFrame::setErrorStateIndicator() should only be used for application testing,
    e.g. on virtual CAN FD busses.

    \sa hasErrorStateIndicator()
*/

/*!
    \class QCanBusFrame::TimeStamp
    \inmodule QtSerialBus
    \since 5.8

    \brief The TimeStamp class provides timestamp information with microsecond precision.
*/

/*!
    \fn TimeStamp::TimeStamp(qint64 s, qint64 usec)

    Constructs a TimeStamp in seconds, \a s, and microseconds, \a usec.

    \note The TimeStamp is not normalized, i.e. microseconds greater 1000000 are not
    converted to seconds.
*/

/*!
    \fn static TimeStamp TimeStamp::fromMicroSeconds(qint64 usec)

    Constructs a normalized TimeStamp from microseconds \a usec.

    The created TimeStamp is normalized, i.e. microseconds greater 1000000 are converted
    to seconds.
*/

/*!
    \fn qint64 TimeStamp::seconds() const

    Returns the seconds of the timestamp.
*/

/*!
    \fn qint64 TimeStamp::microSeconds() const

    Returns the microseconds of the timestamp.
*/

/*!
    Returns the CAN frame as a formatted string.

    The output contains the CAN identifier in hexadecimal format, right
    adjusted to 32 bit, followed by the data length in square brackets
    and the payload in hexadecimal format.

    Standard identifiers are filled with spaces while extended identifiers
    are filled with zeros.

    Typical outputs are:

    \code
        (Error)                                  - error frame
             7FF   [1]  01                       - data frame with standard identifier
        1FFFFFFF   [8]  01 23 45 67 89 AB CD EF  - data frame with extended identifier
             400  [10]  01 23 45 67 ... EF 01 23 - CAN FD frame
             123   [5]  Remote Request           - remote frame with standard identifier
        00000234   [0]  Remote Request           - remote frame with extended identifier
    \endcode
*/
QString QCanBusFrame::toString() const
{
    const FrameType type = frameType();

    switch (type) {
    case InvalidFrame:
        return QStringLiteral("(Invalid)");
    case ErrorFrame:
        return QStringLiteral("(Error)");
    case UnknownFrame:
        return QStringLiteral("(Unknown)");
    default:
        break;
    }

    const char *idFormat = hasExtendedFrameFormat() ? "%08X" : "     %03X";
    const char *dlcFormat = hasFlexibleDataRateFormat() ? "  [%02d]" : "   [%d]";
    QString result;
    result.append(QString::asprintf(idFormat, static_cast<uint>(frameId())));
    result.append(QString::asprintf(dlcFormat, payload().size()));

    if (type == RemoteRequestFrame) {
        result.append(QLatin1String("  Remote Request"));
    } else if (!payload().isEmpty()) {
        const QByteArray data = payload().toHex(' ').toUpper();
        result.append(QLatin1String("  "));
        result.append(QLatin1String(data));
    }

    return result;
}

#ifndef QT_NO_DATASTREAM

/*! \relates QCanBusFrame

    Writes a \a frame to the stream (\a out) and returns a reference
    to the it.
*/
QDataStream &operator<<(QDataStream &out, const QCanBusFrame &frame)
{
    out << frame.frameId();
    out << static_cast<quint8>(frame.frameType());
    out << static_cast<quint8>(frame.version);
    out << frame.hasExtendedFrameFormat();
    out << frame.hasFlexibleDataRateFormat();
    out << frame.payload();
    const QCanBusFrame::TimeStamp stamp = frame.timeStamp();
    out << stamp.seconds();
    out << stamp.microSeconds();
    if (frame.version >= QCanBusFrame::Version::Qt_5_9)
        out << frame.hasBitrateSwitch() << frame.hasErrorStateIndicator();
    return out;
}

/*! \relates QCanBusFrame

    Reads a \a frame from the stream (\a in) and returns a
    reference to the it.
*/
QDataStream &operator>>(QDataStream &in, QCanBusFrame &frame)
{
    quint32 frameId;
    quint8 frameType;
    quint8 version;
    bool extendedFrameFormat;
    bool flexibleDataRate;
    bool bitrateSwitch = false;
    bool errorStateIndicator = false;
    QByteArray payload;
    qint64 seconds;
    qint64 microSeconds;

    in >> frameId >> frameType >> version >> extendedFrameFormat >> flexibleDataRate
       >> payload >> seconds >> microSeconds;

    if (version >= QCanBusFrame::Version::Qt_5_9)
        in >> bitrateSwitch >> errorStateIndicator;

    frame.setFrameId(frameId);
    frame.version = version;

    frame.setFrameType(static_cast<QCanBusFrame::FrameType>(frameType));
    frame.setExtendedFrameFormat(extendedFrameFormat);
    frame.setFlexibleDataRateFormat(flexibleDataRate);
    frame.setBitrateSwitch(bitrateSwitch);
    frame.setErrorStateIndicator(errorStateIndicator);
    frame.setPayload(payload);

    frame.setTimeStamp(QCanBusFrame::TimeStamp(seconds, microSeconds));

    return in;
}

#endif // QT_NO_DATASTREAM

QT_END_NAMESPACE