Fix duplicate call of flushAndClose() if status code is PROTOCOL_ERROR on close() method.

[felippeduran]

This pull request fixes what seems to be a bug.

If the handshake is refused when establishing connection with server, flushAndClose() is called twice, first with CloseFrame.NEVER_CONNECTED, then with CloseFrame.PROTOCOL_ERROR.

[marci4]

Hello @felippeduran,

thx for your pull request.

Do you have some steps to repeat for this bug?
Or have you just found it by code review?

Greetings
marci4

[felippeduran]

Hi, @marci4,

Thanks for the reply!

I found it by inspecting the code. Before that, I was trying to debug a case where the server would return me 503 during the HTTP handshake and I'd get the error CloseFrame.NEVER_CONNECTED, which didn't make much sense for me. Then I realized that the error code was actually CloseFrame.PROTOCOL_ERROR (as the Draft_6455 can't read the success headers to Upgrade the connection) and it was being changed somewhere during the closing state, which led me to this pull request.

So the steps to reproduce would be just to make your server return a status code like 503 during handshake and then try to connect with it.

Cheers!

[marci4]

Hello @felippeduran,

thank you for your answer and your pull request.

Greetings
marci4