source: branches/home/psmith/restructure/src/io/nio-server.lisp @ 65

#|
Copyright (c) 2006 Risto Laakso
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
   notice, this list of conditions and the following disclaimer in the
   documentation and/or other materials provided with the distribution.
3. The name of the author may not be used to endorse or promote products
   derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|#
(in-package :nio)

(declaim (optimize (debug 3) (speed 3) (space 0)))

(defun trivial-accept (client)
  (declare (ignore client))
;;  (format t "Accepting connection from ~S:~D [~A].~%" host port proto)
  t)

;TODO thread safety
(defparameter +connected-sockets+ nil
  "List of sockets that have been connected and are awaiting addition to the event-notification system")

;loop over hashtable 
(defun process-async-fds (client-hash)
  (maphash #'(lambda (k async-fd) 
               (format-log t "Dealing with ~a => ~a~%" k async-fd)
               
               ;process reads
               (when (read-ready async-fd) (read-more async-fd))
               (when (> (buffer-position (foreign-read-buffer async-fd)) 0)
                 (process-read async-fd))

               ;process-writes
               (process-write async-fd)
               (when (and (write-ready async-fd) 
                          (> (buffer-position (foreign-write-buffer async-fd)) 0))
                 (write-more async-fd)))
           client-hash))


                             

(defun start-server (connection-handler accept-filter connection-type 
                     &key 
                     (protocol :inet) 
                     (port (+ (random 60000) 1024)) 
                     (host "localhost") 
                     (accept-connection #'trivial-accept))
                     

  (let (sock
        (event-queue (make-event-queue))
        (client-hash (make-hash-table :test 'eql))
        )

    (setq sock (ecase protocol
                 (:inet (make-inet-socket)) 
                 (:inet6 (make-inet6-socket))))

    (unless (ecase protocol 
              (:inet (bind-inet-socket sock port host))
              (:inet6 (bind-inet6-socket sock port host)))
      (error "Can't bind socket!"))

    (set-fd-nonblocking sock)

    (format t "~&Starting server on ~S port ~S.. (socket fd is ~D)~%" host port sock)

    (start-listen sock)

    (add-fd event-queue sock :read :trigger :level)
           
    (format t "waiting for events..~%") (force-output)

    (catch 'poll-error-exit
      (handler-bind ((poll-error #'(lambda (cond) 
                                     (declare (ignore cond))
                                     (format t "Poll-error (errno ~A), exiting..~%" (get-errno))
                                     (throw 'poll-error-exit nil))))
       
        (loop 
           (let ((unix-epoll-events (poll-events event-queue)))
             (loop for (fd . event) in unix-epoll-events do         
                  (cond
                    ;; new connection
                    ((= fd sock)
                     (let ((async-fd (socket-accept fd connection-type)))
#+nio-debug                    (format t "start-server - New conn: ~A~%" async-fd)
                       (cond
                         ((null async-fd)
                          (format t "Accept failed.~%"))

                         ;; accept connection ?
                         ((funcall accept-connection async-fd)
                          (set-fd-nonblocking (async-fd-read-fd async-fd))
                          (setf (gethash (async-fd-read-fd async-fd) client-hash) async-fd)
                          (add-async-fd event-queue async-fd :read-write)
;                         (add-async-fd event-queue async-fd :write)
                          )

                         ;; no accept, close
                         (t
                          (format-log t "start-server - accept-connection closed~%")
                          (close-async-fd async-fd)))))


                    ;; socket i/o available
                    (t
                     (let ((async-fd (gethash fd client-hash)))
                       (format-log t "IO event ~A on ~A~%" event async-fd)
                       (unless (null async-fd)
                         (catch 'error-exit
                           (handler-bind ((read-error #'(lambda (x) 
                                                          (declare (ignore x))
                                                          (format t "read-error, dropping ~A.~%" async-fd)
                                                          (setf (gethash (async-fd-read-fd async-fd) client-hash) nil)
                                                          (remove-async-fd event-queue async-fd :read)
                                                          (remove-async-fd event-queue async-fd :write)
                                                          (force-close-async-fd async-fd)
                                                          (throw 'error-exit nil))))

                             (when (read-event-p event) (setf (read-ready async-fd) t))
                             (when (write-event-p event) (setf (write-ready async-fd) t)))))))))

                                        ;add outgoing sockets to event queue
             (format-log t "nio-server:start-server - Processing client add ~A~%" +connected-sockets+)
             (loop for new-fd in +connected-sockets+ do
                  (format-log t "nio-server:start-server - Dealing with ~A~%" new-fd)
                  (setf (gethash (async-fd-read-fd new-fd) client-hash) new-fd)
                  (add-async-fd event-queue new-fd :read-write))

                                        ;TODO thread safety
             (setf +connected-sockets+ nil)
             
                                        ;loop over async-fd's processing where necessary
             (process-async-fds client-hash)
                  ))))
    (ignore-errors 
      (close-fd sock))))


(defun add-connection (host port connection-type
                   &key 
                   (protocol :inet)
                   
                   )
  (let ((sock nil))
    (setq sock (ecase protocol
                 (:inet (make-inet-socket)) 
                 (:inet6 (make-inet6-socket))))
    
    (if (connect-inet-socket sock host port)
        (let ((sm (create-state-machine connection-type sock sock sock)))
          (push sm +connected-sockets+) 
          (format-log t "nio-server:add-connection - Socket enqueued: ~A~%" +connected-sockets+)
          (return-from add-connection sm))
        (format t "Connect failed!!~A ~%" (get-errno)))))