Re: When will LispWork has UDP support?

Chun Tian (binghe) wrote:
> Hi, LispWorks
>
> It's strange that LispWorks doesn't have UDP networking support, it's as
> important as TCP, as least I think. It seems that Allegro CL has full
> UDP support, so does SBCL, and OpenMCL.
>
> The IOlib[1] project can be used for portable networking on many UNIX
> platform, but this project cannot used on win32.
>
> So, does anyone have experience on UDP networking using LispWorks
> Windows Edition? Am I must call win32 API directly?
>
> Thanks.
>
> Chun Tian (binghe)
>
>
>   
OK, since still no official answer, I'll do this myself.

Now I'm working on a UDP support of LispWorks, I find LispWorks' comm
package already has many BSD socket functions base on FLI, and I'm
planing to use some of them:

(:STRUCT COMM::SOCKADDR_IN)
COMM::INITIALIZE-SOCKADDR_IN
(INITIALIZE-SOCKADDR_IN INADDR FAMILY HOST SERVICE PROTOCOL)
COMM::*SOCKET_SOCK_STREAM*
COMM::*SOCKET_PF_UNSPEC*
COMM::SOCKET
COMM::BIND
COMM::*SOCKOPT_TCP_NODELAY*
COMM::*SOCKOPT_IPPROTO_TCP*
COMM::SETSOCKOPT
SYSTEM::GET-OS-ERROR-STRING
COMM::SET-SOCKET-NO-BLOCKING
(:STRUCT COMM::SOCKADDR)
COMM::CONNECT
COMM::CLOSE-SOCKET
COMM::WAIT-FOR-CONNECT-TO-COMPLETE
COMM::GETHOSTBYNAME
COMM::INET_ADDR
(:STRUCT COMM:IN_ADDR)
COMM::HTONL
COMM::GET-PORT-FOR-SERVICE
comm::*socket_af_inet*
comm::*socket_sock_stream* (need comm::*socket_sock_dgram*)
COMM::FCNTL

And below are some code I wrote:

(in-package :comm)

(defconstant *socket_pf_inet* 2 "IP protocol family")
(defconstant *socket_sock_dgram* 2
  "Connectionless, unreliable datagrams of fixed maximum length.")

(defclass socket-datagram (socket-stream)
  ()
  (:documentation "UDP Socket"))

(defun open-udp-datagram (hostname
                          service
                          &key
                          (direction :io)
                          (element-type 'base-char)
                          errorp
                          read-timeout
                          write-timeout
                          timeout
                          local-address
                          local-port)
  "learn from open-tcp-stream"
  (let ((socket (connect-to-udp-server hostname service
                                       :errorp errorp
                                       :timeout timeout
                                       :local-address local-address
                                       :local-port local-port)))
    (unwind-protect
        (make-instance 'socket-datagram
                       :init t
                       :socket socket
                       :direction direction
                       :element-type element-type
                       :read-timeout read-timeout
                       :write-timeout write-timeout)
      (close-socket socket))))

I think a UDP interface based on LispWorks' already exist TCP and
socket-stream is quite possible. With help from people, I have runnable
(but not OO based) win32/unix UDP support based on LispWorks' FLI. I
think I can merge them into my initial work.

Wish me good luck, please:)

Chun Tian (binghe)
(A person who want to run his SNMP implementation on LispWorks)