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// 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 "qoscbundle_p.h"
#include "qtuio_p.h"
#include <QtEndian>
#include <QDebug>
#include <QLoggingCategory>
QT_BEGIN_NAMESPACE
Q_LOGGING_CATEGORY(lcTuioBundle, "qt.qpa.tuio.bundle")
QOscBundle::QOscBundle() {}
// 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.
QOscBundle::QOscBundle(const QByteArray &data)
: m_isValid(false)
, m_immediate(false)
, m_timeEpoch(0)
, m_timePico(0)
{
// 8 16 24 32 40 48 56 64
// # b u n d l e \0
// 23 62 75 6e 64 6c 65 00 // OSC string bundle identifier
// 00 00 00 00 00 00 00 01 // osc time-tag, "immediately"
// 00 00 00 30 // element length
// => message or bundle(s), preceded by length each time
qCDebug(lcTuioBundle) << data.toHex();
quint32 parsedBytes = 0;
// "An OSC Bundle consists of the OSC-string "#bundle""
QByteArray identifier;
if (!qt_readOscString(data, identifier, parsedBytes) || identifier != "#bundle")
return;
// "followed by an OSC Time
// Tag, followed by zero or more OSC Bundle Elements. The OSC-timetag is a
// 64-bit fixed point time tag whose semantics are described below."
if (parsedBytes > (quint32)data.size() || data.size() - parsedBytes < qsizetype(sizeof(quint64)))
return;
// "Time tags are represented by a 64 bit fixed point number. The first 32
// bits specify the number of seconds since midnight on January 1, 1900,
// and the last 32 bits specify fractional parts of a second to a precision
// of about 200 picoseconds. This is the representation used by Internet NTP
// timestamps."
//
// (editor's note: one may wonder how a 64bit big-endian number can also be
// two 32bit numbers, without specifying in which order they occur or
// anything, and one may indeed continue to wonder.)
quint32 oscTimeEpoch = qFromBigEndian<quint32>(data.constData() + parsedBytes);
parsedBytes += sizeof(quint32);
quint32 oscTimePico = qFromBigEndian<quint32>(data.constData() + parsedBytes);
parsedBytes += sizeof(quint32);
bool isImmediate = false;
if (oscTimeEpoch == 0 && oscTimePico == 1) {
// "The time tag value consisting of 63 zero bits followed by a
// one in the least significant bit is a special case meaning
// "immediately.""
isImmediate = true;
}
while (parsedBytes < (quint32)data.size()) {
// "An OSC Bundle Element consists of its size and its contents. The size is an
// int32 representing the number of 8-bit bytes in the contents, and will
// always be a multiple of 4."
//
// in practice, a bundle can contain multiple bundles or messages,
// though, and each is prefixed by a size.
if (data.size() - parsedBytes < qsizetype(sizeof(quint32)))
return;
quint32 size = qFromBigEndian<quint32>((const uchar*)data.constData() + parsedBytes);
parsedBytes += sizeof(quint32);
if (data.size() - parsedBytes < size)
return;
if (size == 0) {
// empty bundle; these are valid, but should they be allowed? the
// spec is unclear on this...
qCWarning(lcTuioBundle, "Empty bundle?");
m_isValid = true;
m_immediate = isImmediate;
m_timeEpoch = oscTimeEpoch;
m_timePico = oscTimePico;
return;
}
// "The contents are either an OSC Message or an OSC Bundle.
// Note this recursive definition: bundle may contain bundles."
QByteArray subdata = data.mid(parsedBytes, size);
parsedBytes += size;
// "The contents of an OSC packet must be either an OSC Message or an OSC Bundle.
// The first byte of the packet's contents unambiguously distinguishes between
// these two alternatives."
//
// we're not dealing with a packet here, but the same trick works just
// the same.
QByteArray bundleIdentifier = QByteArray("#bundle\0", 8);
if (subdata.startsWith('/')) {
// starts with / => address pattern => start of a message
QOscMessage subMessage(subdata);
if (subMessage.isValid()) {
m_isValid = true;
m_immediate = isImmediate;
m_timeEpoch = oscTimeEpoch;
m_timePico = oscTimePico;
m_messages.append(subMessage);
} else {
qCWarning(lcTuioBundle, "Invalid sub-message");
return;
}
} else if (subdata.startsWith(bundleIdentifier)) {
// bundle identifier start => bundle
QOscBundle subBundle(subdata);
if (subBundle.isValid()) {
m_isValid = true;
m_immediate = isImmediate;
m_timeEpoch = oscTimeEpoch;
m_timePico = oscTimePico;
m_bundles.append(subBundle);
}
} else {
qCWarning(lcTuioBundle, "Malformed sub-data!");
return;
}
}
}
QT_END_NAMESPACE
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