make-run-request run-request?
run-request-proc run-request-when
- run wrap run-wrap run-wrap-at
+ run-it wrap run run-at run-delay
%current-agenda
start-agenda agenda-run-once))
(time agenda-time))
(define (make-async-prompt-tag)
+ "Make an async prompt tag for an agenda.
+
+Generally done automatically for the user through (make-agenda)."
(make-prompt-tag "prompt"))
(define* (make-agenda #:key
(except-port-map (make-hash-table))
(schedule (make-schedule))
(time (gettimeofday)))
+ ;; TODO: document arguments
+ "Make a fresh agenda."
(make-agenda-intern queue prompt
read-port-map write-port-map except-port-map
schedule time))
+(define (current-agenda-prompt)
+ "Get the prompt for the current agenda; signal an error if there isn't one."
+ (let ((current-agenda (%current-agenda)))
+ (if (not current-agenda)
+ (throw
+ 'no-current-agenda
+ "Can't get current agenda prompt if there's no current agenda!")
+ (agenda-prompt-tag current-agenda))))
+
\f
;;; Schedule
(queue time-segment-queue))
(define (time-segment-right-format time)
+ "Ensure TIME is in the right format.
+
+The right format means (second . microsecond).
+If an integer, will convert appropriately."
+ ;; TODO: add floating point / rational number support.
(match time
;; time is already a cons of second and microsecnd
(((? integer? s) . (? integer? u)) time)
(_ (throw 'invalid-time "Invalid time" time))))
(define* (make-time-segment time #:optional (queue (make-q)))
+ "Make a time segment of TIME and QUEUE
+
+No automatic conversion is done, so you might have to
+run (time-segment-right-format) first."
(make-time-segment-intern time queue))
(define (time< time1 time2)
+ "Check if TIME1 is less than TIME2"
(cond ((< (car time1)
(car time2))
#t)
(else #f)))
(define (time= time1 time2)
+ "Check whether TIME1 and TIME2 are equivalent"
(and (= (car time1) (car time2))
(= (cdr time1) (cdr time2))))
(define (time<= time1 time2)
+ "Check if TIME1 is less than or equal to TIME2"
(or (time< time1 time2)
(time= time1 time2)))
(sec time-delta-sec)
(usec time-delta-usec))
-(define* (make-time-delta sec #:optional usec)
- (make-time-delta-intern sec (or usec 0)))
+(define* (make-time-delta sec #:optional (usec 0))
+ "Make a <time-delta> of SEC seconds and USEC microseconds.
+
+This is used primarily so the agenda can recognize RUN-REQUEST objects
+which are meant "
+ (make-time-delta-intern sec usec))
(define tdelta make-time-delta)
(else time)))
(define (time-delta+ time time-delta)
+ "Increment a TIME by the value of TIME-DELTA"
(time-carry-correct
(cons (+ (car time) (time-delta-sec time-delta))
(+ (cdr time) (time-delta-usec time-delta)))))
(define (time-minus time1 time2)
+ "Subtract TIME2 from TIME1"
(time-carry-correct
(cons (- (car time1) (car time2))
- (- (car time2) (cdr time2)))))
+ (- (cdr time2) (cdr time2)))))
(define (time-plus time1 time2)
+ "Add TIME1 and TIME2"
(time-carry-correct
(cons (+ (car time1) (car time2))
- (+ (car time2) (cdr time2)))))
+ (+ (cdr time2) (cdr time2)))))
(define-record-type <schedule>
(segments schedule-segments set-schedule-segments!))
(define* (make-schedule #:optional segments)
+ "Make a schedule, optionally pre-composed of SEGMENTS"
(make-schedule-intern (or segments '())))
(define (schedule-soonest-time schedule)
;; but at least it'll be reasonably easy to refactor to
;; a more functional setup?
(define (schedule-add! schedule time proc)
+ "Mutate SCHEDULE, adding PROC at an appropriate time segment for TIME"
(let ((time (time-segment-right-format time)))
(define (new-time-segment)
(let ((new-segment
(loop (schedule-segments schedule)))))
(define (schedule-empty? schedule)
+ "Check if the SCHEDULE is currently empty"
(eq? (schedule-segments schedule) '()))
(define (schedule-segments-split schedule time)
segments))
-\f
-;;; Port handling
-;;; =============
-
-(define (make-port-mapping)
- (make-hash-table))
-
-(define* (port-mapping-set! port-mapping port #:optional read write except)
- "Sets port-mapping for reader / writer / exception handlers"
- (if (not (or read write except))
- (throw 'no-handlers-given "No handlers given for port" port))
- (hashq-set! port-mapping port
- `#(,read ,write ,except)))
-
-(define (port-mapping-remove! port-mapping port)
- (hashq-remove! port-mapping port))
-
-;; TODO: This is O(n), I'm pretty sure :\
-;; ... it might be worthwhile for us to have a
-;; port-mapping record that keeps a count of how many
-;; handlers (maybe via a promise?)
-(define (port-mapping-empty? port-mapping)
- "Is this port mapping empty?"
- (eq? (hash-count (const #t) port-mapping) 0))
-
-(define (port-mapping-non-empty? port-mapping)
- "Whether this port-mapping contains any elements"
- (not (port-mapping-empty? port-mapping)))
-
-
\f
;;; Request to run stuff
;;; ====================
-(define-record-type <run-request>
+(define-immutable-record-type <run-request>
(make-run-request proc when)
run-request?
(proc run-request-proc)
(when run-request-when))
-(define* (run proc #:optional when)
+(define* (run-it proc #:optional when)
+ "Make a request to run PROC (possibly at WHEN)"
(make-run-request proc when))
(define-syntax-rule (wrap body ...)
+ "Wrap contents in a procedure"
(lambda ()
body ...))
-(define-syntax-rule (run-wrap body ...)
- (run (wrap body ...)))
+;; @@: Do we really want `body ...' here?
+;; what about just `body'?
+(define-syntax-rule (run body ...)
+ "Run everything in BODY but wrap in a convenient procedure"
+ (make-run-request (wrap body ...) #f))
+
+(define-syntax-rule (run-at body ... when)
+ "Run BODY at WHEN"
+ (make-run-request (wrap body ...) when))
+
+;; @@: Is it okay to overload the term "delay" like this?
+;; Would `run-in' be better?
+(define-syntax-rule (run-delay body ... delay-time)
+ "Run BODY at DELAY-TIME time from now"
+ (make-run-request (wrap body ...) (tdelta delay-time)))
-(define-syntax-rule (run-wrap-at body ... when)
- (run (wrap body ...) when))
+
+\f
+;;; Asynchronous escape to run things
+;;; =================================
+
+;; The future's in futures
+
+(define (make-future call-first on-success on-fail on-error)
+ ;; TODO: add error stuff here
+ (lambda ()
+ (let ((call-result (call-first)))
+ ;; queue up calling the
+ (run (on-success call-result)))))
+
+(define (agenda-on-error agenda)
+ (const #f))
+
+(define (agenda-on-fail agenda)
+ (const #f))
+
+(define* (request-future call-first on-success
+ #:key
+ (agenda (%current-agenda))
+ (on-fail (agenda-on-fail agenda))
+ (on-error (agenda-on-error agenda))
+ (when #f))
+ ;; TODO: error handling
+ ;; do we need some distinction between expected, catchable errors,
+ ;; and unexpected, uncatchable ones? Probably...?
+ (make-run-request
+ (make-future call-first on-success on-fail on-error)
+ when))
+
+(define-syntax-rule (%sync body args ...)
+ "Run BODY asynchronously at a prompt, passing args to make-future.
+
+Pronounced `async' despite the spelling.
+
+8sync was chosen because (async) was already taken and could lead to
+errors, and this version of asynchronous code uses a prompt, so the `a'
+character becomes a `%' prompt :)"
+ (abort-to-prompt (current-agenda-prompt)
+ (wrap body)
+ args ...))
+
+(define-syntax-rule (%sync-at body when args ...)
+ (abort-to-prompt (current-agenda-prompt)
+ (wrap body)
+ #:when when
+ args ...))
+
+(define-syntax-rule (%sync-delay body delay-time args ...)
+ (abort-to-prompt (current-agenda-prompt)
+ (wrap body)
+ #:when (tdelta delay-time)
+ args ...))
\f
;;; Execution of agenda, and current agenda
(define %current-agenda (make-parameter #f))
(define (update-agenda-from-select! agenda)
+ "Potentially (select) on ports specified in agenda, adding items to queue"
(define (hash-keys hash)
(hash-map->list (lambda (k v) k) hash))
(define (get-wait-time)
#:key stop-condition
(get-time gettimeofday)
(handle-ports update-agenda-from-select!))
+ ;; TODO: Document fields
+ "Start up the AGENDA"
(let loop ((agenda agenda))
(let ((agenda
;; @@: Hm, maybe here would be a great place to handle
(agenda-run-once agenda))))
(if (and stop-condition (stop-condition agenda))
'done
- (let* ((new-time (get-time))
- (agenda
- (handle-ports
- ;; 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 agenda (agenda-time) new-time))))
+ (let* ((agenda
+ ;; We have to update the time after ports handled, too
+ ;; because it may have changed after a select
+ (set-field
+ (handle-ports
+ ;; 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 agenda (agenda-time) (get-time)))
+ (agenda-time) (get-time))))
;; Update the agenda's current queue based on
;; currently applicable time segments
(add-segments-contents-to-queue!
- (schedule-extract-until! (agenda-schedule agenda) new-time)
+ (schedule-extract-until! (agenda-schedule agenda) (agenda-time agenda))
(agenda-queue agenda))
(loop agenda))))))
(agenda-prompt-tag agenda)
(lambda ()
(proc))
- ;; TODO
- (lambda (k) k)))
+ (lambda* (resume-with please-run-this . args)
+ (apply request-future please-run-this resume-with
+ args))))
(let ((queue (agenda-queue agenda))
(next-queue (make-q)))
projects / 8sync.git / blobdiff