The dispatcher now accepts '...' as the leading segment of Host and the
trailing segment of Path, this special atom matches any remaining path tail.
When given "cowboy.bugs.dev-extend.eu", host rule ['...', <<"dev-extend">>,
<<"eu">>] matches and fills host_info with [<<"cowboy">>, <<"bugs">>].
When given "/a/b/c/d", path rule [<<"a">>, <<"b">>, '...'] matches and fills
path_info with [<<"c">>, <<"d">>].
The server now does a single recv (or more, but only if needed)
which is then sent to erlang:decode_packet/3 multiple times. Since
most requests are smaller than the default MTU on many platforms,
we benefit from this greatly.
In the case of requests with a body, the server usually read at
least part of the body on the first recv. This is bufferized
properly and used when later retrieving the body.
In the case of pipelined requests, we can end up reading many
requests in a single recv, which are then handled properly using
only the buffer containing the received data.
The type isn't exported by OTP so we don't win much.
Also, inet.erl and file.erl define posix() différently,
so OTP needs to stop being so confuse in the first place
before we can attempt to use it properly.
Of course since requests are a record the response state can be explicitly
overriden, but standard use prevents errors by making sure only one reply
is sent.
* Makes more sense to parse the host only once instead of for each path.
* Allows proper handling of: If the host is not a valid host on the server,
the response MUST be a 400 (Bad Request) error.
