make-time-segment time-segment?
time-segment-time time-segment-queue
- time-< time-= time-<=
+ time-< time-= time-<= time-+
+
+ <time-delta>
+ make-time-delta time-delta?
+ time-delta-sec time-delta-usec
<schedule>
make-schedule schedule?
;;; and with reasonable separation from functional components?
(define-immutable-record-type <agenda>
- (make-agenda-intern queue prompt-tag port-mapping schedule)
+ (make-agenda-intern queue prompt-tag port-mapping schedule time)
agenda?
(queue agenda-queue)
(prompt-tag agenda-prompt-tag)
(port-mapping agenda-port-mapping)
- (schedule agenda-schedule))
+ (schedule agenda-schedule)
+ (time agenda-time))
(define (make-async-prompt-tag)
(make-prompt-tag "prompt"))
(queue (make-q))
(prompt (make-prompt-tag))
(port-mapping (make-port-mapping))
- (schedule (make-schedule)))
- (make-agenda-intern queue prompt port-mapping schedule))
+ (schedule (make-schedule))
+ (time (gettimeofday)))
+ (make-agenda-intern queue prompt port-mapping schedule time))
\f
(or (time-< time1 time2)
(time-= time1 time2)))
+
+(define-record-type <time-delta>
+ (make-time-delta-intern sec usec)
+ time-delta?
+ (sec time-delta-sec)
+ (usec time-delta-usec))
+
+(define* (make-time-delta sec #:optional usec)
+ (make-time-delta-intern sec (or usec 0)))
+
+(define (time-+ time time-delta)
+ (cons (+ (car time) (time-delta-sec time-delta))
+ (+ (cdr time) (time-delta-usec time-delta))))
+
+
(define-record-type <schedule>
(make-schedule-intern segments)
schedule?
;; mutates AND is worst case of O(n) in both space and time :(
;; but at least it'll be reasonably easy to refactor to
;; a more functional setup?
-(define (schedule-add! time proc schedule)
+(define (schedule-add! schedule time proc)
(let ((time (time-segment-right-format time)))
(define (new-time-segment)
(let ((new-segment
(agenda-run-once agenda))))
(if (and stop-condition (stop-condition agenda))
'done
- (loop new-agenda)))))
+ (let ((updated-agenda
+ ;; Adjust the agenda's time just in time
+ ;; We do this here rather than in agenda-run-once to make
+ ;; agenda-run-once's behavior fairly predictable
+ (set-field new-agenda (agenda-time) (gettimeofday))))
+ (loop updated-agenda))))))
(define (agenda-run-once agenda)
"Run once through the agenda, and produce a new agenda
(let* ((proc (q-pop! queue))
(proc-result (call-proc proc))
(enqueue
- (lambda (new-proc)
- (enq! next-queue new-proc))))
+ (lambda (run-request)
+ (define (schedule-at! time proc)
+ (schedule-add! (agenda-schedule agenda) time proc))
+ (let ((request-time (run-request-when run-request)))
+ (match request-time
+ ((? time-delta? time-delta)
+ (let ((time (time-+ (agenda-time agenda)
+ time-delta)))
+ (schedule-at! time (run-request-proc proc))))
+ ((? integer? sec)
+ (let ((time (cons sec 0)))
+ (schedule-at! time (run-request-proc proc))))
+ (((? integer? sec) . (? integer? usec))
+ (schedule-at! request-time (run-request-proc proc)))
+ (#f
+ (enq! next-queue (run-request-proc run-request))))))))
;; @@: We might support delay-wrapped procedures here
(match proc-result
;; TODO: replace procedure with something that indicates
;; intent to run. Use a (run foo) procedure
- ((? procedure? new-proc)
+ ((? run-request? new-proc)
(enqueue new-proc))
- (((? procedure? new-procs) ...)
+ (((? run-request? new-procs) ...)
(for-each
(lambda (new-proc)
(enqueue new-proc))
new-procs))
;; do nothing
(_ #f))))
- ;; TODO: Selecting on ports would happen here?
+ ;; TODO: Alternately, we could return the next-queue
+ ;; along with changes to be added to the schedule here?
;; Return new agenda, with next queue set
(set-field agenda (agenda-queue) next-queue)))