MessageBuilder: header partial read

[zii-dmg]

WatsonTcp/src/WatsonTcp/WatsonMessageBuilder.cs

Line 107 in 49d796e

await stream.ReadAsync(headerBytes, 0, 24, token).ConfigureAwait(false);

There is no check for read count so header can be read partially. Then array has zero bytes at end and check for zeros generates exception "Null header data indicates peer disconnected". There should be while (readCount < 24) loop. I think I got partial reads on real network because logs contains "Null header data indicates peer disconnected".

Also read can return 0 count for gracefully closed socket.

Line:

WatsonTcp/src/WatsonTcp/WatsonMessageBuilder.cs

Line 130 in 49d796e

await stream.ReadAsync(headerBuffer, 0, 1, token).ConfigureAwait(false);

Also should check for 0 count.

[sancheolz]

In addition: the client breaks the loop by IOException and calls HandleServerDisconnected in

WatsonTcp/src/WatsonTcp/WatsonTcpClient.cs

Line 982 in 49d796e

_Events?.HandleServerDisconnected(this, new DisconnectionEventArgs(null, reason));

But at the same time, SendAsync is waiting on the server and it will not be released by CancelationToken.Cancel, because the client does not call Disconnect(), which should have sent the Shutdown packet. The TCP connection is active, and the client is in the _Connected = false state.
As a result, we have a hung thread on the sending side.

[sancheolz]

Related to #263.
I think the deadlock is happening there due to receiving an incomplete header. Setting NoDelay = true just hid the problem.

[jchristn]

Resolving in 6.0.8, uploading in a few moments.