X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcode%2Fserve-event.lisp;h=b1a6eedca9364c9cb1c87ec298b35e29b459c06c;hb=0c3bbfaa2286626a2d915c8810f690aefc702661;hp=2046161d50e586c83450b675759062e2e446511b;hpb=3d446163adb5602f4cf4743fb7f97ad187a6b2c0;p=sbcl.git diff --git a/src/code/serve-event.lisp b/src/code/serve-event.lisp index 2046161..b1a6eed 100644 --- a/src/code/serve-event.lisp +++ b/src/code/serve-event.lisp @@ -66,12 +66,14 @@ ;;; Add a new handler to *descriptor-handlers*. (defun add-fd-handler (fd direction function) #!+sb-doc - "Arange to call FUNCTION whenever FD is usable. DIRECTION should be + "Arrange to call FUNCTION whenever FD is usable. DIRECTION should be either :INPUT or :OUTPUT. The value returned should be passed to SYSTEM:REMOVE-FD-HANDLER when it is no longer needed." (unless (member direction '(:input :output)) ;; FIXME: should be TYPE-ERROR? (error "Invalid direction ~S, must be either :INPUT or :OUTPUT" direction)) + (unless (<= 0 fd (1- sb!unix:fd-setsize)) + (error "Cannot add an FD handler for ~D: not under FD_SETSIZE limit." fd)) (let ((handler (make-handler direction fd function))) (with-descriptor-handlers (push handler *descriptor-handlers*)) @@ -88,8 +90,8 @@ ;;; Search *descriptor-handlers* for any reference to fd, and nuke 'em. (defun invalidate-descriptor (fd) #!+sb-doc - "Remove any handers refering to fd. This should only be used when attempting - to recover from a detected inconsistancy." + "Remove any handlers referring to FD. This should only be used when attempting + to recover from a detected inconsistency." (with-descriptor-handlers (setf *descriptor-handlers* (delete fd *descriptor-handlers* @@ -138,42 +140,80 @@ ;;;; SERVE-ALL-EVENTS, SERVE-EVENT, and friends +;;; When a *periodic-polling-function* is defined the server will not +;;; block for more than the maximum event timeout and will call the +;;; polling function if it does time out. +(declaim (type (or null symbol function) *periodic-polling-function*)) +(defvar *periodic-polling-function* nil + "Either NIL, or a designator for a function callable without any +arguments. Called when the system has been waiting for input for +longer then *PERIODIC-POLLING-PERIOD* seconds. Shared between all +threads, unless locally bound. EXPERIMENTAL.") +(declaim (real *periodic-polling-period*)) +(defvar *periodic-polling-period* 0 + "A real number designating the number of seconds to wait for input +at maximum, before calling the *PERIODIC-POLLING-FUNCTION* \(if any.) +Shared between all threads, unless locally bound. EXPERIMENTAL.") + ;;; Wait until FD is usable for DIRECTION. The timeout given to serve-event is ;;; recalculated each time through the loop so that WAIT-UNTIL-FD-USABLE will ;;; timeout at the correct time irrespective of how many events are handled in ;;; the meantime. -(defun wait-until-fd-usable (fd direction &optional timeout) +(defun wait-until-fd-usable (fd direction &optional timeout (serve-events t)) #!+sb-doc "Wait until FD is usable for DIRECTION. DIRECTION should be either :INPUT or :OUTPUT. TIMEOUT, if supplied, is the number of seconds to wait before giving -up." - (prog (usable) +up. Returns true once the FD is usable, NIL return indicates timeout. + +If SERVE-EVENTS is true (the default), events on other FDs are served while +waiting." + (tagbody :restart (multiple-value-bind (to-sec to-usec stop-sec stop-usec signalp) (decode-timeout timeout) (declare (type (or integer null) to-sec to-usec)) - (with-fd-handler (fd direction (lambda (fd) - (declare (ignore fd)) - (setf usable t))) - (loop - (sub-serve-event to-sec to-usec signalp) - (when usable - (return-from wait-until-fd-usable t)) - (when to-sec - (multiple-value-bind (sec usec) - (decode-internal-time (get-internal-real-time)) - (setf to-sec (- stop-sec sec)) - (cond ((> usec stop-usec) - (decf to-sec) - (setf to-usec (- (+ stop-usec 1000000) usec))) - (t - (setf to-usec (- stop-usec usec))))) - (when (or (minusp to-sec) (minusp to-usec)) - (if signalp - (progn - (signal-deadline) - (go :restart)) - (return-from wait-until-fd-usable nil))))))))) + (flet ((maybe-update-timeout () + ;; If we return early, recompute the timeouts, possibly + ;; signaling the deadline or returning with NIL to caller. + (setf (values to-sec to-usec) + (relative-decoded-times stop-sec stop-usec)) + (when (and (zerop to-sec) (not (plusp to-usec))) + (cond (signalp + (signal-deadline) + (go :restart)) + (t + (return-from wait-until-fd-usable nil)))))) + (if (and serve-events + ;; No timeout or non-zero timeout + (or (not to-sec) + (not (= 0 to-sec to-usec))) + ;; Something to do while we wait + (or *descriptor-handlers* *periodic-polling-function*)) + ;; Loop around SUB-SERVE-EVENT till done. + (dx-let ((usable (list nil))) + (dx-flet ((usable! (fd) + (declare (ignore fd)) + (setf (car usable) t))) + (with-fd-handler (fd direction #'usable!) + (loop + (sub-serve-event to-sec to-usec signalp) + (when (car usable) + (return-from wait-until-fd-usable t)) + (when to-sec + (maybe-update-timeout)))))) + ;; If we don't have to serve events, just poll on the single FD instead. + (loop for to-msec = (if (and to-sec to-usec) + (+ (* 1000 to-sec) (truncate to-usec 1000)) + -1) + when (or #!+win32 (eq direction :output) + #!+win32 (sb!win32:handle-listen + (sb!win32:get-osfhandle fd)) + #!-win32 + (sb!unix:unix-simple-poll fd direction to-msec)) + do (return-from wait-until-fd-usable t) + else + do (when to-sec (maybe-update-timeout)) + #!+win32 (sb!thread:thread-yield))))))) ;;; Wait for up to timeout seconds for an event to happen. Make sure all ;;; pending events are processed before returning. @@ -201,21 +241,6 @@ happens. Server returns T if something happened and NIL otherwise. Timeout (declare (ignore stop-sec stop-usec)) (sub-serve-event to-sec to-usec signalp))) -;;; When a *periodic-polling-function* is defined the server will not -;;; block for more than the maximum event timeout and will call the -;;; polling function if it does time out. -(declaim (type (or null symbol function) *periodic-polling-function*)) -(defvar *periodic-polling-function* nil - "Either NIL, or a designator for a function callable without any -arguments. Called when the system has been waiting for input for -longer then *PERIODIC-POLLING-PERIOD* seconds. Shared between all -threads, unless locally bound. EXPERIMENTAL.") -(declaim (real *periodic-polling-period*)) -(defvar *periodic-polling-period* 0 - "A real number designating the number of seconds to wait for input -at maximum, before calling the *PERIODIC-POLLING-FUNCTION* \(if any.) -Shared between all threads, unless locally bound. EXPERIMENTAL.") - ;;; Takes timeout broken into seconds and microseconds, NIL timeout means ;;; to wait as long as needed. (defun sub-serve-event (to-sec to-usec deadlinep) @@ -296,7 +321,11 @@ Shared between all threads, unless locally bound. EXPERIMENTAL.") (ecase (handler-direction handler) (:input (sb!unix:fd-isset fd read-fds)) (:output (sb!unix:fd-isset fd write-fds))))))) - (funcall (handler-function handler) - (handler-descriptor handler))) + (with-simple-restart (remove-fd-handler "Remove ~S" handler) + (funcall (handler-function handler) + (handler-descriptor handler)) + (go :next)) + (remove-fd-handler handler) + :next) t))))))