Fix WebSocket bug with Firefox

[mikesart]

Creating Websocket with Firefox v28.0 on Linux was failing because Connection header was "keep-alive, Upgrade" and code was looking for "Upgrade".

[deplinenoise]

I think this change breaks legitimately passing "upgrade" (i.e. in lower case.) strstr() is case sensitive.

[mikesart]

Yep - good catch. Try #2...

[deplinenoise]

Maybe it would be cleaner to just lowercase everything as we pull it in, and do away with these slow case-insensitive functions? Also, you seem to have accidentally snuck in another unrelated change here in the pull request.

[mikesart]

Maybe it would be cleaner to just lowercase everything as we pull it in, and do away with these slow case-insensitive functions?

Lowercase all the headers as they come in or just specific headers like "Connection"? Happy to switch over to doing that - it was just more of a global change and I'm not up on all the RFCs to know whether that's legal everywhere or legal/fast on specific headers or what.

Also, you seem to have accidentally snuck in another unrelated change here in the pull request.

Sorry - that should have been in another branch. Moved it over and created another pull request.

[deplinenoise]

I was thinking maybe just lowercasing a few of the troublesome ones like this one as we tokenize the data. But maybe that's even uglier? Not sure.

Looking at your code in the mean while, I think I still see a problem. If Connection is set to UpdateFooBar it will be match the Update prefix and return a false positive.

[mikesart]

Is it just whitespace, comma, or nil that could end the token?

[deplinenoise]

I don't know; I thought the header was supposed to just say "Upgrade" in this case. Can you dig a little in the RFCs and find out? (Sorry; I'm under water with other projects right now.)

[mikesart]

The WebSocket Protocol includes these phrases:

• If the response lacks a |Connection| header field or the |Connection| header field doesn't contain a token ...
• A |Connection| header field that includes the token "Upgrade" ...
• A |Connection| header field with value "Upgrade".

That appears to leave room for tokens other than just Upgrade. For whatever it's worth, the Qt test suite sets Connection to "Upgrade,keepalive". (Which I think is a bug - should be Keep-Alive.)

https://qt.gitorious.org/qt/qtwebsockets/source/ea7c77e87f317cd72278ba4f9955b74b9cdfeedf:tests/auto/handshakerequest/tst_handshakerequest.cpp

Documention for Connection and Keep-Alive:

http://tools.ietf.org/html/rfc2068#section-19.7.1

Token grammar documentation: http://www.packetizer.com/rfc/rfc2616/

I'll go through this when I get unburied a bit...