public static TDSHeader Read(TDSReader r) // TODo - not all token types have a TDS Header, like APPDATA or perhaps SSPI - needs more research
{
TDSHeader head = new TDSHeader();
head.PacketType = r.ReadByte();
if (head.PacketType != (byte)TDSPacketType.SQLBATCH &&
head.PacketType != (byte)TDSPacketType.LOGIN &&
head.PacketType != (byte)TDSPacketType.RPC &&
head.PacketType != (byte)TDSPacketType.RESPONSE &&
head.PacketType != (byte)TDSPacketType.ATTENTION &&
head.PacketType != (byte)TDSPacketType.BULKLOAD &&
head.PacketType != (byte)TDSPacketType.DTC &&
head.PacketType != (byte)TDSPacketType.LOGIN7 &&
head.PacketType != (byte)TDSPacketType.SSPI &&
head.PacketType != (byte)TDSPacketType.PRELOGIN &&
head.PacketType != (byte)TDSPacketType.APPDATA)
{
throw new InvalidTDSException("Unknown token type: " + head.PacketType);
}
head.Status = r.ReadByte();
if (head.Status > 31)
{
throw new InvalidTDSException("Unknown Status value: " + head.Status); // supposed to ignore other flag fields
}
head.Length = r.ReadBigEndianUInt16();
head.SPID = r.ReadBigEndianUInt16();
head.PacketID = r.ReadByte();
head.Window = r.ReadByte();
if (head.Window != 0)
{
throw new InvalidTDSException("Invalid TDS Window value: " + head.Window); // supposed to ignore
}
return(head);
}
public TDSHeader GetTDSHeader()
{
TDSHeader head = null;
TDSReader r = null; // TDSReader does not need to be closed; GC is all it needs
try
{
r = new TDSReader(payload, 0); // header does not span packets, so we can read without aggregating
head = TDSHeader.Read(r);
}
catch (Exception) { return(null); } // null if error
return(head);
}
public TDSHeader GetTDSHeader()
{
if (frames == null)
{
throw new InvalidOperationException("Packet must have at least one frame.");
}
TDSHeader head = null;
TDSReader r = null; // TDSReader does not need to be closed; GC is all it needs
try
{
r = new TDSReader(((FrameData)(frames[0])).payload, 0); // header does not span packets, so we can read without aggregating
head = TDSHeader.Read(r);
}
catch (Exception) { return(null); } // null if error
return(head);
}
