Initial commit

Lts/Proxies/GuezNasat/tcp_socket_handler.cpp

@@ -0,0 +1,160 @@
+/**
+  * Websocket interface for building control unit
+  * $Id$
+  * $HeadURL$
+  * $Author$
+  * Created by Christian Ehrlicher, SLSE, 2017-01-30
+  */
+
+#include "tcp_socket_handler.h"
+#include "guez_nasat_telegrams.h"
+
+namespace GuezNasat
+{
+static constexpr unsigned char s_startMark = 0x02;
+static constexpr unsigned char s_endMark = 0x03;
+static inline QByteArray escapeData(const QByteArray &bufferData)
+{
+  QByteArray ret;
+  ret.reserve(bufferData.size() * 6 / 5);
+  for (const unsigned char c : bufferData)
+  {
+    if (c >= 0x20 && c < 0x7f)
+      ret += c;
+    else
+      ret += "\\x" + QByteArray::number(static_cast<unsigned char>(c), 16);
+  }
+  return ret;
+}
+
+TcpSocketHandler::TcpSocketHandler(QObject *parent)
+  : AbstractSocketHandler("TcpSocketHandler", parent)
+  , m_tcpSocketServer(new QTcpServer(this))
+{
+  TRACE_LOG(m_logger) << LOGFUNCTION << " START";
+  TRACE_LOG(m_logger) << LOGFUNCTION << " END";
+}
+
+bool TcpSocketHandler::init(quint16 listenPort)
+{
+  if (!m_tcpSocketServer->listen(QHostAddress::Any, listenPort))
+  {
+    WARNING_LOG(m_logger) << "Can not listen on port " << listenPort << " - aborting";
+    return false;
+  }
+  connect(m_tcpSocketServer, &QTcpServer::newConnection,
+          this, &TcpSocketHandler::onNewConnection);
+
+  return true;
+}
+
+void TcpSocketHandler::onNewConnection()
+{
+  QTcpSocket *ts = m_tcpSocketServer->nextPendingConnection();
+  if (!ts)
+    return;
+  DEBUG_LOG(m_logger) << "New TCP socket connection from " << ts->peerAddress().toString()
+                      << ":" << ts->peerPort() << ", ptr: " << ts;
+
+  connect(ts, &QTcpSocket::readyRead,
+          this, &TcpSocketHandler::onReadyRead);
+  connect(ts, &QTcpSocket::disconnected,
+          this, &TcpSocketHandler::onTcpSocketDisconnected);
+
+  m_tcpSockets.insert(ts, QByteArray());
+}
+
+bool TcpSocketHandler::sendTelegramInternal(const QByteArray &tele)
+{
+  if (tele.size() > std::numeric_limits<unsigned short>::max())
+    return false;
+  const unsigned short len = tele.size();
+  // add framing
+  QByteArray data(len + 4, Qt::Uninitialized);  // s_startMark, len, s_endMark
+  data[0] = s_startMark;
+  // big endian
+  data[1] = (len & 0x00FFU);
+  data[2] = (len & 0xFF00U) >> 16;
+  char *dst = data.data() + 3;
+  memcpy(dst, tele.data(), tele.size());
+  data[data.size() - 1] = s_endMark;
+
+  bool bOk = false;
+  DEBUG_LOG(m_logger) << "Sending: " << escapeData(data);
+  for (auto it = m_tcpSockets.cbegin(); it != m_tcpSockets.cend(); ++it)
+  {
+    QTcpSocket *ws = it.key();
+    if (ws->write(data) <= 0)
+      bOk = true;
+  }
+  return bOk;
+}
+
+void TcpSocketHandler::onReadyRead()
+{
+  QTcpSocket *s = qobject_cast<QTcpSocket *>(sender());
+  if (!s)
+  {
+    Q_ASSERT(false);
+    return;
+  }
+  auto &tcpBuffer = m_tcpSockets[s];
+  const QByteArray bufferData = tcpBuffer + s->readAll();
+  TRACE_LOG(m_logger) << "TcpSocketHandler::onReadyRead bufferData='" << escapeData(bufferData) << "'";
+  // returns the unparsed part of the buffer
+  tcpBuffer = parseBuffer(bufferData);
+}
+
+QByteArray TcpSocketHandler::parseBuffer(const QByteArray &buffer)
+{
+  int iEndPos = 0;
+  int iCurReadPos = 0;
+  while (findNextSyncStartByte(buffer, iCurReadPos))
+  {
+    const int iStartPos = iCurReadPos;
+    if (!findNextSyncEndByte(buffer, iCurReadPos))
+      break;
+    iEndPos = iCurReadPos;
+    // after s_startMark there are two bytes with len, we currently don't care about them
+    textMessageReceived(buffer.mid(iStartPos + 3, iEndPos - iStartPos - 3));
+  }
+  return buffer.mid(iEndPos);
+}
+
+bool TcpSocketHandler::findNextSyncStartByte(const QByteArray &buffer, int &iCurReadPos)
+{
+  // Suchen nach s_startMark
+  while (iCurReadPos < buffer.size())
+  {
+    const unsigned char data = buffer.at(iCurReadPos);
+    if (data == s_startMark)
+      return true;
+    ++iCurReadPos;
+  }
+  return false;
+}
+
+bool TcpSocketHandler::findNextSyncEndByte(const QByteArray &buffer, int &iCurReadPos)
+{
+  // Suchen nach s_endMark
+  while (iCurReadPos < buffer.size())
+  {
+    const unsigned char data = buffer.at(iCurReadPos);
+    if (data == s_endMark)
+      return true;
+    ++iCurReadPos;
+  }
+  return false;
+}
+
+void TcpSocketHandler::onTcpSocketDisconnected()
+{
+  QTcpSocket *ws = qobject_cast<QTcpSocket *>(sender());
+  if (!ws)
+    return;
+  DEBUG_LOG(m_logger) << "TCP socket connection closed, ptr: " << ws;
+  m_tcpSockets.remove(ws);
+  ws->deleteLater();
+}
+
+} // namespace GuezNasat