MINOR: mux: implement a get_first_cs() method
This method is used to retrieve the first known good conn_stream from
the mux. It will be used to find the other end of a connection when
dealing with the proxy protocol for example.
diff --git a/include/types/connection.h b/include/types/connection.h
index 889decb..ebc60e4 100644
--- a/include/types/connection.h
+++ b/include/types/connection.h
@@ -321,6 +321,7 @@
void (*shutw)(struct conn_stream *cs, enum cs_shw_mode); /* shutw function */
struct conn_stream *(*attach)(struct connection *); /* Create and attach a conn_stream to an outgoing connection */
+ const struct conn_stream *(*get_first_cs)(const struct connection *); /* retrieves any valid conn_stream from this connection */
void (*detach)(struct conn_stream *); /* Detach a conn_stream from an outgoing connection, when the request is done */
void (*show_fd)(struct buffer *, struct connection *); /* append some data about connection into chunk for "show fd" */
int (*subscribe)(struct conn_stream *cs, int event_type, void *param); /* Subscribe to events, such as "being able to send" */