This adds h2 http support for the client api.
The public client api requires no changes, it will detect by
ALPN if the server can handle http/2, if so, it will use it.
Multiple client connections using the lws api will be mapped on
to the same single http/2 + tls socket using http/2 streams
that are serviced simultaneously where possible.
Until now LWS_CALLBACK_CLIENT_CONNECTION_ERROR handling could only
take place on protocols[0].
This patch changes LWS_CALLBACK_CLIENT_CONNECTION_ERROR to be sent
to the protocol the client connection was bound to... if nothing
better that is still protocols[0], but if you created the client
connection using info.local_protocol_name, it will now be sent to
the bound protocol handler instead.
In the case you are creating a client connection, there may be
no relationship between the ws protocol you want to bind to at
the server, and the local protocol name you want the wsi to
bind to at the client.
This introduces a new client info struct member .local_protocol_name,
if it is NULL then all is as before, otherwise it binds the client
wsi to the named protocol early in the process, and .protocol is used
for the negotiation with the ws server.
This allows you to bind client wsi to local protocol handlers that
don't share the name of the ws protocol the connection will try
to negotiate.
The union used to make a lot of sense to save space between
mutually exclusive modes. But the fact the http2 struct
contains the http1 struct as well as it appearing in the
union means the http1 struct belongs outside the union.
This patch
- eliminates the union
- puts the http_related struct directly in struct lws
- removes http_related from h2
- puts h2 directly in struct lws if enabled for build
- changes ws to be a pointer, allocated if we upgrade to ws
(the ws part contains a 135 byte char array for ping / close)
Again all of this is entirely private / internal and doesn't affect
any apis.
Migrate what used to be in lws_hdr_related into either the ah
or the wsi, and eliminate it along with the three different ways
used to access things inside it.
Eg wsi->u.hdr.ah and wsi->u.http.ah become wsi->ah
These changes are internal-only, in private-libwebsockets.h and lib.
