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/*
# Copyright (c) 2009 - OpenSLX Project, Computer Center University of Freiburg
#
# This program is free software distributed under the GPL version 2.
# See http://openslx.org/COPYING
#
# If you have any feedback please consult http://openslx.org/feedback and
# send your suggestions, praise, or complaints to feedback@openslx.org
#
# General information about OpenSLX can be found at http://openslx.org/
# -----------------------------------------------------------------------------
# src/net/mcast/McastReceiver.h
# - implement the receiver-side multicast file transfer protocol -- implementation
# -----------------------------------------------------------------------------
*/
#include <QDataStream>
#include <QtDebug>
#include <QtGlobal>
#include <pgm/pgm.h>
// OpenPGM #defines bool. This is bad in C++.
#undef bool
#include "McastConstants.h"
#include "McastReceiver.h"
McastReceiver::McastReceiver(QIODevice* iodev, McastConfiguration* config, QObject* parent) :
QObject(parent),
_config(config ? new McastConfiguration(*config) : new McastConfiguration()),
_socket(0),
_curoffs(0),
_closed(false),
_hash(QCryptographicHash::Md5),
_iodev(iodev)
{
_config->setParent(this);
}
McastReceiver::~McastReceiver()
{
if (_config)
delete _config;
}
void McastReceiver::start()
{
_socket = new McastPGMSocket(this);
connect(_socket, SIGNAL(receivedPacket(QByteArray)), this, SLOT(receivedPacket(QByteArray)));
connect(_socket, SIGNAL(connectionReset()), this, SLOT(connectionReset()));
// connect(_socket, SIGNAL(connectionFinished()), this, SLOT(connectionFinished()));
_socket->open(_config, McastPGMSocket::PSOCK_READ);
}
void McastReceiver::receivedPacket(QByteArray const& bytes)
{
if(_closed)
return;
quint16 checksum_should = qChecksum(bytes.constData(), bytes.size() - 2);
QDataStream strm(bytes);
strm.setByteOrder(QDataStream::BigEndian);
// read the packet
quint64 magic;
quint64 offset;
quint16 checksum;
strm >> magic;
if(magic != MCASTFT_MAGIC)
{
qCritical() << "Received packet whose magic number does not match. Ignoring.";
return;
}
strm >> offset;
qDebug() << " Received packet for offset" << offset;
if (offset == UINT64_C(0xffffffffffffffff))
{
// this is the end of the data stream.
QByteArray md5;
strm >> md5;
quint16 fchecksum;
strm >> fchecksum;
// compare the hash value
if ((fchecksum != checksum_should) || (md5 != _hash.result()))
{
_close(RES_MD5_MISMATCH);
}
else
{
_close(RES_OK);
}
return;
}
else if (offset != _curoffs)
{
qCritical() << "Packet loss or double delivery. PGM should have prevented this. Bailing out.";
_close(RES_OFFSET_MISMATCH);
return;
}
QByteArray contents;
strm >> contents;
_curoffs += contents.size();
strm >> checksum;
if(checksum != checksum_should)
{
qCritical() << "Checksum does not match. Bailing out.";
_close(RES_CHECKSUM_MISMATCH);
return;
}
_hash.addData(contents);
_iodev->write(contents);
emit progress(_curoffs);
}
void McastReceiver::connectionReset()
{
_close(RES_CONNECTION_RESET);
}
void McastReceiver::_close(Result result)
{
_iodev->close();
_socket->finish();
_closed = true;
emit finished(result);
}
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