/// <summary>
/// Creates a serialized request packet (DtmPacket)
/// </summary>
private MemoryStream CreateRequest(DtmPacketFlags Message, short State)
{
MemoryStream ret = new DtmPacketStruct(Message, 0, 0, State).ToStream();
ret.Seek(0, SeekOrigin.Begin);
return(ret);
}
/// <summary>
/// DtmPacketStruct primary constructor
/// </summary>
///
/// <param name="PacketType">The <see cref="DtmPacketFlags"/> message type; describes the packet classification</param>
/// <param name="PayloadLength">The length of the payload contained in the packet</param>
/// <param name="Sequence">The packet sequence number</param>
/// <param name="PacketFlag">The <see cref="DtmServiceFlags"/> exchange state; indicates the exchange state position</param>
/// <param name="OptionFlag">The packet header option flag</param>
public DtmPacketStruct(DtmPacketFlags PacketType, long PayloadLength, int Sequence, short PacketFlag, long OptionFlag = 0)
{
this.PacketType = PacketType;
this.PayloadLength = PayloadLength;
this.Sequence = Sequence;
this.PacketFlag = PacketFlag;
this.OptionFlag = OptionFlag;
}
/// <summary>
/// Reset all struct members
/// </summary>
public void Reset()
{
PacketType = 0;
PayloadLength = 0;
Sequence = 0;
PacketFlag = 0;
OptionFlag = 0;
}
/// <summary>
/// Extracts a DtmPacket from a Stream
/// </summary>
///
/// <param name="PacketStream">The Stream containing the DtmPacket structure</param>
public DtmPacketStruct(Stream PacketStream)
{
BinaryReader reader = new BinaryReader(PacketStream);
PacketType = (DtmPacketFlags)reader.ReadUInt16();
PayloadLength = reader.ReadInt64();
Sequence = reader.ReadInt32();
PacketFlag = reader.ReadInt16();
OptionFlag = reader.ReadInt64();
}
private void Transmit(DtmPacketFlags PacketType, short PacketFlag, long OptionFlag = 0, MemoryStream Payload = null)
{
lock (_sndLock)
{
long pldLen = Payload == null ? 0 : Payload.Length;
// create a new packet: packet flag, payload size, sequence, and state flag
MemoryStream pktStm = new DtmPacketStruct(PacketType, pldLen, _sndSequence, PacketFlag, OptionFlag).ToStream();
// add payload
if (Payload != null)
{
// copy to output
pktStm.Seek(0, SeekOrigin.End);
Payload.WriteTo(pktStm);
pktStm.Seek(0, SeekOrigin.Begin);
}
// store in the file packet buffer
_sndBuffer.Push(_sndSequence, pktStm);
// increment file send counter
_sndSequence++;
// transmit to remote client
if (_clientSocket.IsConnected)
{
try
{
_clientSocket.SendAsync(pktStm);
}
catch (CryptoSocketException ce)
{
SocketException se = ce.InnerException as SocketException;
if (se.SocketErrorCode == SocketError.WouldBlock ||
se.SocketErrorCode == SocketError.IOPending ||
se.SocketErrorCode == SocketError.NoBufferSpaceAvailable)
{
// buffer is full, throttle down
Throttle(pktStm);
}
else
{
// possible connection dropped, alert app
if (SessionError != null)
{
DtmErrorArgs args = new DtmErrorArgs(ce, DtmErrorSeverityFlags.Connection);
SessionError(this, args);
}
}
}
catch (Exception ex)
{
// possible connection dropped, alert app
if (SessionError != null)
{
DtmErrorArgs args = new DtmErrorArgs(ex, DtmErrorSeverityFlags.Connection);
SessionError(this, args);
}
}
// notify app
if (PacketSent != null)
{
PacketSent(this, new DtmPacketArgs((short)DtmTransferFlags.DataChunk, pldLen));
}
}
}
}
