Mercurial > demo / examples/net/yoctochat.lisp

 ;;; examples/net/yoctochat.lisp --- Yoctochat Implementation
 
 ;; The tiniest (lisp) chat server on earth!
 
 ;; based on https://github.com/robn/yoctochat
 
 ;; A 'yoctochat' server will:
 
 ;; - take a single commandline argument, the port to listen on
 ;; - open a listening port
 ;; - handle multiple connections and disconnections on that port
 ;; - receive text on a connection, and forward it on to all ofhter connections
 ;; - produce simple output about what it's doing
 ;; - demonstrate a single IO multiplexing technique as simply as possible
 ;; - be well commented!
 
 ;;; Commentary:
 
 ;; This implementation is based on the yc_uring.c implementation which
 ;; uses io_uring. To use io_uring from Lisp, we use the high-level IO
 ;; package, which internally calls foreign functions defined in the
 ;; URING package.
 
 ;; 
 
 ;;; Code:
 (defpackage :examples/yoctochat
   (:use :cl :std :net :cli/clap :io :log :sb-alien)
   (:import-from :uring :load-uring))
 
 (in-package :examples/yoctochat)
 
 ;; To start using the IO package we should make sure the liburing
 ;; shared library is properly loaded. This function takes care of that
 ;; and arranges for the library to be remembered when entering a saved
 ;; lisp image such that it will be automatically re-opened.
 (load-uring t)
 
 ;; Initialize a simple logger to report on what's happening.
 ;; (setq *logger* (make-logger nil))
 
 ;; Define some parameters for the queue depth and maximum number of
 ;; connections allowed on a single server.
 (defparameter *num-conns* 128)
 
 (defparameter *queue-depth* (* 2 *num-conns*))
 
 (defclass yc-server (server)
   ((connections :initform nil ::type sequence))
   (:documentation "The Yoctochat Server. "))
 
 ;; The main loop of our yoctochat server. The 'defmain' macro will
 ;; produce a function 'main' which can be saved as an executable
 ;; entry-point.
 (defmain ()
   (init-io *queue-depth*)
   (setf *io* nil))