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#include <QtCore/QDebug>
#include <QtCore/QTimerEvent>
#include "sappeer.h"
#include "sapconnection.h"
#include "sapsocket.h"
#define DELAYED_ACK_TIME 1000
#define WINDOW_SIZE_MSGS 10
SAPSocket::SAPSocket(SAPConnection *conn, int sessionId, const SAPChannelInfo &chanInfo) :
QObject(conn), _sessionId(sessionId), _info(chanInfo), _open(false),
_outLastSeqNum(0), _outLastAck(0), _inLastSeqNum(0), _inLastAck(0)
{
}
SAPPeer * SAPSocket::peer()
{
return connection()->peer();
}
SAPConnection * SAPSocket::connection()
{
return static_cast<SAPConnection*>(parent());
}
SAPChannelInfo SAPSocket::channelInfo() const
{
return _info;
}
bool SAPSocket::isOpen() const
{
return _open;
}
bool SAPSocket::messageAvailable() const
{
return !_in.empty();
}
QByteArray SAPSocket::receive()
{
if (!_in.empty()) {
return _in.dequeue();
} else {
return QByteArray();
}
}
bool SAPSocket::send(const QByteArray &data)
{
SAProtocol::DataFrame frame;
if (!isOpen()) {
qWarning() << "Socket is not yet open";
return false;
}
if (data.size() > 65000) {
qWarning() << "Fragmentation is not yet supported";
return false;
}
if (_out.size() > WINDOW_SIZE_MSGS) {
// Send buffer is not empty; enqueue
// TODO Realiability
}
frame.withSeqNum = isWithSeqNum();
if (isReliable()) {
frame.seqNum = ++_outLastSeqNum;
} else {
frame.seqNum = 0;
}
frame.unk_1 = 0; // Is this related to fragmentation?
frame.data = data;
peer()->writeDataToSession(_sessionId, SAProtocol::packDataFrame(frame));
return true;
}
void SAPSocket::setOpen(bool open)
{
_open = open;
}
void SAPSocket::acceptIncomingData(const QByteArray &data)
{
if (data.isEmpty()) return;
SAProtocol::DataFrame frame = SAProtocol::unpackDataFrame(data, isWithSeqNum());
if (isReliable()) {
quint16 expectedSeqNum = _inLastSeqNum + 1;
if (frame.seqNum != expectedSeqNum) {
qWarning() << "Unexpected sequence number" << frame.seqNum
<< "on session" << _sessionId
<< "(expected " << expectedSeqNum << ")";
} else {
_inLastSeqNum = frame.seqNum;
if (!_timer.isActive()) {
_timer.start(DELAYED_ACK_TIME, Qt::CoarseTimer, this);
}
}
}
_in.enqueue(frame.data);
emit messageReceived();
}
int SAPSocket::sessionId() const
{
return _sessionId;
}
void SAPSocket::timerEvent(QTimerEvent *event)
{
if (event->timerId() == _timer.timerId()) {
if (_inLastSeqNum != _inLastAck) {
peer()->writeAckToSession(_sessionId, _inLastSeqNum);
_inLastAck = _inLastSeqNum;
}
_timer.stop();
} else {
QObject::timerEvent(event);
}
}
bool SAPSocket::isReliable() const
{
return _info.qosType() == SAPChannelInfo::QoSReliabilityEnable;
}
bool SAPSocket::isWithSeqNum() const
{
return _info.qosType() == SAPChannelInfo::QoSReliabilityDisable ||
_info.qosType() == SAPChannelInfo::QoSReliabilityEnable;
}
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