#!+sb-doc
"List of all the currently active handlers for file descriptors")
-(defvar *descriptor-handler-lock*
- (sb!thread::make-spinlock :name "descriptor handle lock"))
-
(sb!xc:defmacro with-descriptor-handlers (&body forms)
;; FD-STREAM functionality can add and remove descriptors on it's
- ;; own, and two threads adding add the same time could lose one.
- ;;
- ;; This is never held for long, so a spinlock is fine.
- `(without-interrupts
- (sb!thread::with-spinlock (*descriptor-handler-lock*)
- ,@forms)))
+ ;; own, so getting an interrupt while modifying this and the
+ ;; starting to recursively modify it could lose...
+ `(without-interrupts ,@forms))
(defun list-all-descriptor-handlers ()
(with-descriptor-handlers
;;; 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*))
;;; 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*
(sb!unix:unix-fstat (handler-descriptor handler)))
(setf (handler-bogus handler) t)
(push handler bogus-handlers)))
- (restart-case (error "~S ~[have~;has a~:;have~] bad file descriptor~:P."
- bogus-handlers (length bogus-handlers))
- (remove-them ()
- :report "Remove bogus handlers."
- (with-descriptor-handlers
- (setf *descriptor-handlers*
- (delete-if #'handler-bogus *descriptor-handlers*))))
- (retry-them ()
- :report "Retry bogus handlers."
- (dolist (handler bogus-handlers)
- (setf (handler-bogus handler) nil)))
- (continue ()
- :report "Go on, leaving handlers marked as bogus."))))
+ (when bogus-handlers
+ (restart-case (error "~S ~[have~;has a~:;have~] bad file descriptor~:P."
+ bogus-handlers (length bogus-handlers))
+ (remove-them ()
+ :report "Remove bogus handlers."
+ (with-descriptor-handlers
+ (setf *descriptor-handlers*
+ (delete-if #'handler-bogus *descriptor-handlers*))))
+ (retry-them ()
+ :report "Retry bogus handlers."
+ (dolist (handler bogus-handlers)
+ (setf (handler-bogus handler) nil)))
+ (continue ()
+ :report "Go on, leaving handlers marked as bogus."))))
+ nil)
+
\f
;;;; SERVE-ALL-EVENTS, SERVE-EVENT, and friends
-;;; Break a real timeout into seconds and microseconds.
-(defun decode-timeout (timeout)
- (declare (values (or index null) index))
- (typecase timeout
- (integer (values timeout 0))
- (null (values nil 0))
- (real
- (multiple-value-bind (q r) (truncate (coerce timeout 'single-float))
- (declare (type index q) (single-float r))
- (values q (the (values index t) (truncate (* r 1f6))))))
- (t
- (error "Timeout is not a real number or NIL: ~S" timeout))))
+;;; 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."
- (declare (type (or real null) timeout))
- (let (usable)
- (multiple-value-bind (to-sec to-usec) (decode-timeout timeout)
- (declare (type (or index null) to-sec to-usec))
- (multiple-value-bind (stop-sec stop-usec)
- (if to-sec
- (multiple-value-bind (okay start-sec start-usec)
- (sb!unix:unix-gettimeofday)
- (declare (ignore okay))
- (let ((usec (+ to-usec start-usec))
- (sec (+ to-sec start-sec)))
- (declare (type (unsigned-byte 31) usec sec))
- (if (>= usec 1000000)
- (values (1+ sec) (- usec 1000000))
- (values sec usec))))
- (values 0 0))
- (declare (type (unsigned-byte 31) stop-sec stop-usec))
- (with-fd-handler (fd direction (lambda (fd)
- (declare (ignore fd))
- (setf usable t)))
- (loop
- (sub-serve-event to-sec to-usec)
+:OUTPUT. TIMEOUT, if supplied, is the number of seconds to wait before giving
+up. Returns true once the FD is usable, NIL return indicates timeout.
- (when usable
- (return t))
-
- (when timeout
- (multiple-value-bind (okay sec usec) (sb!unix:unix-gettimeofday)
- (declare (ignore okay))
- (when (or (> sec stop-sec)
- (and (= sec stop-sec) (>= usec stop-usec)))
- (return nil))
- (setq to-sec (- stop-sec sec))
- (cond ((> usec stop-usec)
- (decf to-sec)
- (setq to-usec (- (+ stop-usec 1000000) usec)))
- (t
- (setq to-usec (- stop-usec usec))))))))))))
+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))
+ (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)))))))
\f
;;; Wait for up to timeout seconds for an event to happen. Make sure all
;;; pending events are processed before returning.
(defun serve-all-events (&optional timeout)
#!+sb-doc
"SERVE-ALL-EVENTS calls SERVE-EVENT with the specified timeout. If
- SERVE-EVENT does something (returns T) it loops over SERVE-EVENT with timeout
- 0 until all events have been served. SERVE-ALL-EVENTS returns T if
- SERVE-EVENT did something and NIL if not."
+SERVE-EVENT does something (returns T) it loops over SERVE-EVENT with a
+timeout of 0 until there are no more events to serve. SERVE-ALL-EVENTS returns
+T if SERVE-EVENT did something and NIL if not."
(do ((res nil)
(sval (serve-event timeout) (serve-event 0)))
((null sval) res)
(setq res t)))
-;;; Serve a single event.
+;;; Serve a single set of events.
(defun serve-event (&optional timeout)
#!+sb-doc
- "Receive on all ports and Xevents and dispatch to the appropriate handler
- function. If timeout is specified, server will wait the specified time (in
- seconds) and then return, otherwise it will wait until something happens.
- Server returns T if something happened and NIL otherwise."
- (multiple-value-bind (to-sec to-usec) (decode-timeout timeout)
- (sub-serve-event to-sec to-usec)))
-
-;;; 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 function) *periodic-polling-function*))
-(defvar *periodic-polling-function* nil)
-(declaim (type (unsigned-byte 29) *max-event-to-sec* *max-event-to-usec*))
-(defvar *max-event-to-sec* 1)
-(defvar *max-event-to-usec* 0)
-
-;;; Takes timeout broken into seconds and microseconds.
-(defun sub-serve-event (to-sec to-usec)
- (declare (type (or null (unsigned-byte 29)) to-sec to-usec))
+ "Receive pending events on all FD-STREAMS and dispatch to the appropriate
+handler functions. If timeout is specified, server will wait the specified
+time (in seconds) and then return, otherwise it will wait until something
+happens. Server returns T if something happened and NIL otherwise. Timeout
+0 means polling without waiting."
+ (multiple-value-bind (to-sec to-usec stop-sec stop-usec signalp)
+ (decode-timeout timeout)
+ (declare (ignore stop-sec stop-usec))
+ (sub-serve-event to-sec to-usec signalp)))
- (let ((call-polling-fn nil))
- (when (and *periodic-polling-function*
- ;; Enforce a maximum timeout.
- (or (null to-sec)
- (> to-sec *max-event-to-sec*)
- (and (= to-sec *max-event-to-sec*)
- (> to-usec *max-event-to-usec*))))
- (setf to-sec *max-event-to-sec*)
- (setf to-usec *max-event-to-usec*)
- (setf call-polling-fn t))
+;;; 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)
+ (or
+ (if *periodic-polling-function*
+ (multiple-value-bind (p-sec p-usec)
+ (decode-internal-time
+ (seconds-to-internal-time *periodic-polling-period*))
+ (if to-sec
+ (loop repeat (/ (+ to-sec (/ to-usec 1e6))
+ *periodic-polling-period*)
+ thereis (sub-sub-serve-event p-sec p-usec)
+ do (funcall *periodic-polling-function*))
+ (loop thereis (sub-sub-serve-event p-sec p-usec)
+ do (funcall *periodic-polling-function*))))
+ (sub-sub-serve-event to-sec to-usec))
+ (when deadlinep
+ (signal-deadline))))
- ;; Next, wait for something to happen.
- (sb!alien:with-alien ((read-fds (sb!alien:struct sb!unix:fd-set))
- (write-fds (sb!alien:struct sb!unix:fd-set)))
- (sb!unix:fd-zero read-fds)
- (sb!unix:fd-zero write-fds)
- (let ((count 0))
- (declare (type index count))
+;;; Handles the work of the above, except for periodic polling. Returns
+;;; true if something of interest happened.
+(defun sub-sub-serve-event (to-sec to-usec)
+ (sb!alien:with-alien ((read-fds (sb!alien:struct sb!unix:fd-set))
+ (write-fds (sb!alien:struct sb!unix:fd-set)))
+ (sb!unix:fd-zero read-fds)
+ (sb!unix:fd-zero write-fds)
+ (let ((count 0))
+ (declare (type index count))
- ;; Initialize the fd-sets for UNIX-SELECT and return the active
- ;; descriptor count.
- (map-descriptor-handlers
- (lambda (handler)
- ;; FIXME: If HANDLER-ACTIVE ever is reinstanted, it needs
- ;; to be checked here in addition to HANDLER-BOGUS
- (unless (handler-bogus handler)
- (let ((fd (handler-descriptor handler)))
- (ecase (handler-direction handler)
- (:input (sb!unix:fd-set fd read-fds))
- (:output (sb!unix:fd-set fd write-fds)))
- (when (> fd count)
- (setf count fd))))))
- (incf count)
+ ;; Initialize the fd-sets for UNIX-SELECT and return the active
+ ;; descriptor count.
+ (map-descriptor-handlers
+ (lambda (handler)
+ ;; FIXME: If HANDLER-ACTIVE ever is reinstanted, it needs
+ ;; to be checked here in addition to HANDLER-BOGUS
+ (unless (handler-bogus handler)
+ (let ((fd (handler-descriptor handler)))
+ (ecase (handler-direction handler)
+ (:input (sb!unix:fd-set fd read-fds))
+ (:output (sb!unix:fd-set fd write-fds)))
+ (when (> fd count)
+ (setf count fd))))))
+ (incf count)
- (multiple-value-bind (value err)
- (sb!unix:unix-fast-select count
- (sb!alien:addr read-fds)
- (sb!alien:addr write-fds)
- nil to-sec to-usec)
- #!+win32 (declare (ignorable err))
- (cond ((eql 0 value)
- ;; Timed out.
- (when call-polling-fn
- (funcall *periodic-polling-function*)))
- (value
- ;; Call file descriptor handlers according to the
- ;; readable and writable masks returned by select.
- (dolist (handler
- (select-descriptor-handlers
- (lambda (handler)
- (let ((fd (handler-descriptor handler)))
- (ecase (handler-direction handler)
- (:input (sb!unix:fd-isset fd read-fds))
- (:output (sb!unix:fd-isset fd write-fds)))))))
+ ;; Next, wait for something to happen.
+ (multiple-value-bind (value err)
+ (sb!unix:unix-fast-select count
+ (sb!alien:addr read-fds)
+ (sb!alien:addr write-fds)
+ nil to-sec to-usec)
+ #!+win32
+ (declare (ignore err))
+ ;; Now see what it was (if anything)
+ (cond ((not value)
+ ;; Interrupted or one of the file descriptors is bad.
+ ;; FIXME: Check for other errnos. Why do we return true
+ ;; when interrupted?
+ #!-win32
+ (case err
+ (#.sb!unix:ebadf
+ (handler-descriptors-error))
+ ((#.sb!unix:eintr #.sb!unix:eagain)
+ t)
+ (otherwise
+ (with-simple-restart (continue "Ignore failure and continue.")
+ (simple-perror "Unix system call select() failed"
+ :errno err))))
+ #!+win32
+ (handler-descriptors-error))
+ ((plusp value)
+ ;; Got something. Call file descriptor handlers
+ ;; according to the readable and writable masks
+ ;; returned by select.
+ (dolist (handler
+ (select-descriptor-handlers
+ (lambda (handler)
+ (let ((fd (handler-descriptor handler)))
+ (ecase (handler-direction handler)
+ (:input (sb!unix:fd-isset fd read-fds))
+ (:output (sb!unix:fd-isset fd write-fds)))))))
+ (with-simple-restart (remove-fd-handler "Remove ~S" handler)
(funcall (handler-function handler)
- (handler-descriptor handler)))
- t)
- #!-win32
- ((eql err sb!unix:eintr)
- ;; We did an interrupt.
- ;;
- ;; FIXME: Why T here?
- t)
- (t
- ;; One of the file descriptors is bad.
- (handler-descriptors-error)
- nil)))))))
+ (handler-descriptor handler))
+ (go :next))
+ (remove-fd-handler handler)
+ :next)
+ t))))))
projects / sbcl.git / blobdiff