qoscmessage.cpp

Go to the documentation of this file.

// Copyright (C) 2014 Robin Burchell <robin.burchell@viroteck.net>
// Copyright (C) 2016 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
 
#include "qoscmessage_p.h"
#include "qtuio_p.h"
 
#include <QDebug>
#include <QtEndian>
#include <QLoggingCategory>
 
QT_BEGIN_NAMESPACE
 
Q_LOGGING_CATEGORY(lcTuioMessage, "qt.qpa.tuio.message")
 
QOscMessage::QOscMessage() {}
 
// TUIO packets are transmitted using the OSC protocol, located at:
//   http://opensoundcontrol.org/specification
// Snippets of this specification have been pasted into the source as a means of
// easily communicating requirements.
 
QOscMessage::QOscMessage(const QByteArray &data)
    : m_isValid(false)
{
    qCDebug(lcTuioMessage) << data.toHex();
    quint32 parsedBytes = 0;
 
    // "An OSC message consists of an OSC Address Pattern"
    QByteArray addressPattern;
    if (!qt_readOscString(data, addressPattern, parsedBytes) || addressPattern.size() == 0)
        return;
 
    // "followed by an OSC Type Tag String"
    QByteArray typeTagString;
    if (!qt_readOscString(data, typeTagString, parsedBytes))
        return;
 
    // "Note: some older implementations of OSC may omit the OSC Type Tag string.
    // Until all such implementations are updated, OSC implementations should be
    // robust in the case of a missing OSC Type Tag String."
    //
    // (although, the editor notes one may question how exactly the hell one is
    // supposed to be robust when the behavior is unspecified.)
    if (typeTagString.size() == 0 || typeTagString.at(0) != ',')
        return;
 
    QList<QVariant> arguments;
 
    // "followed by zero or more OSC Arguments."
    for (int i = 1; i < typeTagString.size(); ++i) {
        char typeTag = typeTagString.at(i);
        if (typeTag == 's') { // osc-string
            QByteArray aString;
            if (!qt_readOscString(data, aString, parsedBytes))
                return;
            arguments.append(aString);
        } else if (typeTag == 'i') { // int32
            if (parsedBytes > (quint32)data.size() || data.size() - parsedBytes < qsizetype(sizeof(quint32)))
                return;
 
            quint32 anInt = qFromBigEndian<quint32>(data.constData() + parsedBytes);
            parsedBytes += sizeof(quint32);
 
            // TODO: is int32 in OSC signed, or unsigned?
            arguments.append((int)anInt);
        } else if (typeTag == 'f') { // float32
            if (parsedBytes > (quint32)data.size() || data.size() - parsedBytes < qsizetype(sizeof(quint32)))
                return;
 
            static_assert(sizeof(float) == sizeof(quint32));
            union {
                quint32 u;
                float f;
            } value;
            value.u = qFromBigEndian<quint32>(data.constData() + parsedBytes);
            parsedBytes += sizeof(quint32);
            arguments.append(value.f);
        } else {
            qCWarning(lcTuioMessage) << "Reading argument of unknown type " << typeTag;
            return;
        }
    }
 
    m_isValid = true;
    m_addressPattern = addressPattern;
    m_arguments = arguments;
 
    qCDebug(lcTuioMessage) << "Message with address pattern: " << addressPattern << " arguments: " << arguments;
}
 
QT_END_NAMESPACE