protected virtual void OnConnectionLost()
{
_isConnected = false;
_connectionMonitorState = ConnectionMonitorState.AttemptingToConnect;
if (ConnectionLost != null)
{
try
{
ConnectionLost(this, new EventArgs());
}
catch
{
// just catch the error in the user code and continue.
}
}
try
{
// Since OnConnectionLost can be called from a superclass (such as from the TcpCommunication.readCallback()) we need to change the timer to _connectionAttemptInterval.
if (_connectionMonitorEnabled && _connectionMonitorTimer != null) // just in case it was disabled while the above was running.
{
//System.Diagnostics.Debug.WriteLine(DateTime.Now.ToString() + "************************************** OnConnectionLost Setting timer interval to " + _connectionAttemptInterval);
_connectionMonitorTimer.Change(_connectionAttemptInterval, System.Threading.Timeout.Infinite);
}
}
catch
{
}
}
/// <summary>
/// Add the specified data to the internal buffer and parses the buffer for delimited data.
/// </summary>
public void ProcessReceivedData(byte[] data, int byteCount)
{
//System.Diagnostics.Debug.WriteLine(DateTime.Now.ToString() + " " + System.Reflection.Assembly.GetEntryAssembly().GetName().Name + " " + System.Threading.Thread.CurrentThread.GetHashCode() + " ProcessReceivedData received utf8: " + Encoding.UTF8.GetString(data, 0, byteCount));
lock (_readBufferString_lock)
{
_lastReceivedDataDateTime = DateTime.Now;
startCommunicatingTimer();
try
{
if (_totalReceivedByteCount != ulong.MaxValue) // did we already max out?
checked // force OverflowException on overflow.
{
_totalReceivedByteCount += (ulong)byteCount;
}
}
catch (OverflowException)
{
_totalReceivedByteCount = ulong.MaxValue;
}
if (_connectionMonitorEnabled)
{
if (_connectionMonitorTimer != null)
_connectionMonitorTimer.Change(_connectionMonitorTimeout, System.Threading.Timeout.Infinite);
_connectionMonitorState = ConnectionMonitorState.Connected;
}
//**************************************************************
// Check for connection reestablished
//**************************************************************
if (_isConnected == false)
OnConnectionEstablished();
//**************************************************************
// Write the data to the user accessible buffer.
//**************************************************************
if (_bufferReader != null && MaximumReadBufferSize > 0)
{
if (_bufferReader.Length + byteCount <= MaximumReadBufferSize)
{
// Append all the incoming bytes to the buffer.
_bufferReader.WriteInternal(data, 0, byteCount);
}
else
{
// Fill the rest of the buffer with as many bytes as we can.
_bufferReader.WriteInternal(data, 0, MaximumReadBufferSize - (int)_bufferReader.Length);
OnBufferOverflow(); // let the user know that the buffer overflowed.
}
}
//*****************************************************************************************************************
// Fire the ReceivedBytes.
//*****************************************************************************************************************
OnReceivedBytes(data, byteCount);
//*******************************************************
// Decode the bytes to a string.
//*******************************************************
string receivedString = null;
if (_encoding != null)
{
//*******************************************************
// Copy the data to the end of the existing byte buffer.
//*******************************************************
try
{
byte[] tempStringDecodingBuffer = new byte[_stringDecodingBuffer.Length + byteCount];
System.Buffer.BlockCopy(_stringDecodingBuffer, 0, tempStringDecodingBuffer, 0, _stringDecodingBuffer.Length);
System.Buffer.BlockCopy(data, 0, tempStringDecodingBuffer, _stringDecodingBuffer.Length, byteCount);
_stringDecodingBuffer = tempStringDecodingBuffer;
tempStringDecodingBuffer = null;
}
catch (Exception ex)
{
//System.Diagnostics.Debugger.Break();
_logger.Error("An error occurred while copying the data to the end of the existing byte buffer.", ex);
}
//*********************************************************************************************************************
// Convert the bytes to a string (keeping track of how any good bytes there are in case a character spans two buffers.
//*********************************************************************************************************************
Decoder decoder = _encoding.GetDecoder();
int charCount = decoder.GetCharCount(_stringDecodingBuffer, 0, _stringDecodingBuffer.Length);
char[] chars = new char[charCount];
decoder.GetChars(_stringDecodingBuffer, 0, _stringDecodingBuffer.Length, chars, 0);
//**************************************************************
// Add the received string to the buffer.
//**************************************************************
//System.Diagnostics.Debug.WriteLine(DateTime.Now.ToString() + " " + System.Reflection.Assembly.GetEntryAssembly().GetName().Name + " " + System.Threading.Thread.CurrentThread.GetHashCode() + " ProcessReceivedData buffer before: " + _readBufferString);
receivedString = new string(chars);
_readBufferString += receivedString;
//System.Diagnostics.Debug.WriteLine(DateTime.Now.ToString() + " " + System.Reflection.Assembly.GetEntryAssembly().GetName().Name + " " + System.Threading.Thread.CurrentThread.GetHashCode() + " ProcessReceivedData buffer after: " + _readBufferString);
// Determine how many bytes were actually decoded.
Encoder encoder = _encoding.GetEncoder();
int decodedByteCount = encoder.GetByteCount(chars, 0, charCount, false);
// Determine how many bytes at the end of the buffer are unprocessed partial utf8 bytes.
int unprocessedByteCount = _stringDecodingBuffer.Length - decodedByteCount;
try
{
// Set _stringDecodingBuffer to the unprocessed left over (partial character) bytes at the end.
byte[] tempStringDecodingBuffer = new byte[unprocessedByteCount];
System.Buffer.BlockCopy(_stringDecodingBuffer, decodedByteCount, tempStringDecodingBuffer, 0, unprocessedByteCount);
_stringDecodingBuffer = tempStringDecodingBuffer;
tempStringDecodingBuffer = null;
}
catch (Exception ex)
{
//System.Diagnostics.Debugger.Break();
_logger.Error("An error occurred while setting _stringDecodingBuffer to the unprocessed left over (partial character) bytes at the end.", ex);
}
}
//*****************************************************************************************************************
// Fire the ReceivedString.
//*****************************************************************************************************************
if (string.IsNullOrEmpty(receivedString)) // only fire the event if we decoded at least one character.
OnReceivedString(receivedString);
// NOTE: I WAS USING a StringBuilder object for both the logs and the input buffer, but it unexpectidly seemed to causes crashes!?!?
if (_delimiter != null && _readBufferString.Length > 0)
{
//System.Diagnostics.Debug.WriteLine(DateTime.Now.ToString() + " " + System.Threading.Thread.CurrentThread.GetHashCode() + " " + "BaseCommunication.ProcessReceivedData() processing: " + _readBufferString.Replace("\r", "<CR>").Replace("\n", "<LF>"));
// Loop over buffer processing any full responses.
int eolPos = _readBufferString.IndexOf(_delimiter);
while (eolPos >= 0)
{
// Pull out response from buffer
string response;
if (_includeDelimiterInRawResponse)
response = _readBufferString.Substring(0, eolPos + _delimiter.Length).Trim();
else
response = _readBufferString.Substring(0, eolPos).Trim();
_readBufferString = _readBufferString.Remove(0, eolPos + _delimiter.Length);
//System.Diagnostics.Debug.WriteLine(DateTime.Now.ToString() + " " + System.Reflection.Assembly.GetEntryAssembly().GetName().Name + " " + System.Threading.Thread.CurrentThread.GetHashCode() + " ProcessReceivedData extracted response: " + response);
//System.Diagnostics.Debug.WriteLine(DateTime.Now.ToString() + " " + System.Reflection.Assembly.GetEntryAssembly().GetName().Name + " " + System.Threading.Thread.CurrentThread.GetHashCode() + " ProcessReceivedData buffer after removal: " + _readBufferString);
//TODO:OnLog("port_DataReceived() received '" + response + "'");
OnReceivedDelimitedString(response, _includeDelimiterInRawResponse);
eolPos = _readBufferString.IndexOf(_delimiter);
}
}
else
{
// There is no delimiter, so just clear the string buffer so it doesn't grow.
_readBufferString = "";
// Don't clear the byte buffer since it can contain partial character bytes for the decoder.
}
//TODO:OnLog("port_DataReceived() Exiting ^-^-^-^-^");
}
}
protected virtual void OnConnectionAttempt()
{
try
{
open(); // attempt to open the connection.
}
catch (Exception ex)
{
// If it failed to connect the just return. The driver should test the Connected property after calling Open() or StartMonitoring().
// The typical reasons for failure at this time are:
// * Serial Port does not exist: NOT RECOVERABLE, however the configuration system only shows existing COM ports when the user created the device which is helpful.
// * Serial Port already opened: RECOVERABLE (unless more than one driver is configured to use the same port)... once the other process releases the serial port, the connection monitoring will have access to the port.
// * Tcp connection could not be established: RECOVERABLE if the Address is correct.
// * Tcp network card is not installed: NOT RECOVERABLE
OnConnectionAttemptFailed(ex);
throw;
}
// Successfull Connection
_connectionMonitorState = ConnectionMonitorState.Connected;
OnConnectionEstablished();
}
void _connectionMonitorTimer_Elapsed(Object stateInfo)
{
if (_connectionMonitorEnabled)
{
int timerInterval = _connectionMonitorTimeout;
// If we haven't received any data in a while...
try
{
TimeSpan timeSinceReceived = DateTime.Now - _lastReceivedDataDateTime;
//System.Diagnostics.Debug.WriteLine("TIME SINCE LAST RECEIVED DATA: " + timeSinceReceived.ToString());
switch (_connectionMonitorState)
{
case ConnectionMonitorState.AttemptingToConnect:
// Attempt to make a connection
try
{
OnConnectionAttempt(); // the serial class overrides this and does nothing if the serial connection has already been opened.
}
catch
{
// don't throw an error if it fails
}
timerInterval = _connectionAttemptInterval;
break;
case ConnectionMonitorState.Connected:
// We haven't received data in the time limit so send out the test connection request.
_connectionMonitorState = ConnectionMonitorState.Connected_WaitingForResponse; // set this to waiting whether there is a test request to send out or not.
if (_connectionMonitorTestRequestBytes != null && _connectionMonitorTestRequestBytes.Length > 0)
{
// Send the request since we haven't received anything for a while.
try
{
timerInterval = _connectionMonitorWaitForResponseTimeout;
//#if DEBUG
//if (_connectionMonitorTestRequestString != null && _connectionMonitorTestRequestString.Length > 0)
// System.Diagnostics.Debug.WriteLine(DateTime.Now.ToString() + " " + System.Threading.Thread.CurrentThread.GetHashCode() + " _connectionMonitorTimer_Elapsed() sending: " + _connectionMonitorTestRequestString.Replace("\r", "<CR>").Replace("\n", "<LF>"));
//else
// System.Diagnostics.Debug.WriteLine(DateTime.Now.ToString() + " " + System.Threading.Thread.CurrentThread.GetHashCode() + " _connectionMonitorTimer_Elapsed() sending: " + global::Common.SystemUtility.ByteArrayToHexString(_connectionMonitorTestRequestBytes, " "));
//#endif
Send(_connectionMonitorTestRequestBytes);
}
catch
{
// just catch the error in and continue
}
}
// Fire the ConnectionMonitorTest event.
OnConnectionMonitorTest();
break;
case ConnectionMonitorState.Connected_WaitingForResponse:
// We were connected, but didn't receive a response after the request,
// so we are now considered disconnected.
_logger.Error("Connection monitoring sent a request after " + (_connectionMonitorTimeout/1000) + " seconds of device silence and failed to receive a response from the device within " + (_connectionMonitorWaitForResponseTimeout/1000) + " seconds so the connection is assumed to be lost.");
OnConnectionLost();
timerInterval = _connectionAttemptInterval;
// Attempt to reconnect
try
{
OnConnectionAttempt(); // the serial class overrides this and does nothing if the serial connection has already been opened.
}
catch
{
// don't throw an error if it fails
}
break;
}
}
catch (Exception ex)
{
// do nothing
}
finally
{
if (_connectionMonitorEnabled && _connectionMonitorTimer != null) // just in case it was disabled while the above was running.
{
//System.Diagnostics.Debug.WriteLine(DateTime.Now.ToString() + "************************************** _connectionMonitorTimer_Elapsed-finally Setting timer interval to " + timerInterval);
try
{
// I've seen this be null even though we just checked that, so I wrapped it in a try/catch.
_connectionMonitorTimer.Change(timerInterval, System.Threading.Timeout.Infinite);
}
catch
{
// _connectionMonitorTimer was probably null so ignore it.
}
}
}
}
}
