;;;; prefork-client.lisp ;;;; ;;;; A very simple SBCL network client for use in testing the servers in ;;;; prefork-example-simple.lisp and prefork-example-realistic.lisp.

;;;; Copyright (C) 2004, Thomas F. Burdick ;;;; ;;;; Permission is hereby granted, free of charge, to any person obtaining a ;;;; copy of this software and associated documentation files (the "Software"), ;;;; to deal in the Software without restriction, including without limitation ;;;; the rights to use, copy, modify, merge, publish, distribute, sublicense, ;;;; and/or sell copies of the Software, and to permit persons to whom the ;;;; Software is furnished to do so, subject to the following conditions: ;;;; ;;;; The above copyright notice and this permission notice shall be included in ;;;; all copies or substantial portions of the Software. ;;;; ;;;; THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR ;;;; IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, ;;;; FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE ;;;; AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER ;;;; LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING ;;;; FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS ;;;; IN THE SOFTWARE.

(in-package :cl-user)

(eval-when (:load-toplevel :compile-toplevel :execute) (require :sb-posix) (require :sb-bsd-sockets) (use-package :sb-bsd-sockets))

;;; The client is broken across many functions in order to make it easier to ;;; poke at the server. ;;; ;;; We send a line identifying ourselves, then an s-expression. The server ;;; identifies itself, then sends our s-expression back to us.

(defvar *socket* nil) (defvar *stream* nil)

(defun client (&optional object) "Return the echo from the server as multiple values." (client-connect) (client-herald) (client-write (with-output-to-string (s) (print object s))) (multiple-value-prog1 (client-results) (socket-close *socket*)))

;;; ;;; Easily hang server processes ;;;

(defvar *hung* (queue))

(defun hang (&optional (n 1)) "Send N partial requests to the server, causing the processes to hang." (dotimes (i n) (let (*socket* *stream*) (client-connect) (client-herald) (client-write "(:hang ") (queue-add (cons *socket* *stream*) *hung*))))

(defun release (&optional (n 1)) "Send the rest of a proper request to N hung servers." (loop repeat n for pair = (queue-pop *hung*) when pair collect (destructuring-bind (*socket* . *stream*) pair (client-write ":release) ") (client-results))))

;;; ;;; The guts ;;;

(defun client-connect () (setf *socket* (make-instance 'inet-socket :type :stream :protocol :tcp)) (socket-connect *socket* (make-inet-address "127.0.0.1") 1978) (setf *stream* (socket-make-stream *socket* :input t :output t)))

(defun client-herald () (format *stream* "PID ~D~%" (sb-posix:getpid)) (finish-output *stream*))

(defun client-write (string) "Send STRING to the server. If this is an incomplete sexp, it can be used to hang the server." (write-string string *stream*) (finish-output *stream*))

(defun client-results () (values (read-line *stream*) (read *stream*)))

;;; ;;; Misc utils ;;;

(defstruct (queue (:constructor %make-queue (list tail))) (list nil :type list) (tail nil :type list))

(defun queue (&rest elements) (make-queue elements))

(defun make-queue (&optional list) (%make-queue list (last list)))

(defun queue-add (item queue) (if (null (queue-tail queue)) (setf (queue-list queue) (list item) (queue-tail queue) (queue-list queue)) (setf (cdr (queue-tail queue)) (list item) (queue-tail queue) (cdr (queue-tail queue)))) queue)

(defun queue-pop (queue) (prog1 (pop (queue-list queue)) (when (null (queue-list queue)) (setf (queue-tail queue) nil))))