X-Git-Url: https://jxself.org/git/?a=blobdiff_plain;f=loopy.scm;h=01c0b52110d1615648242b9672259479bf7ef350;hb=1b92ec2ba2bcb0aed0e519c558cd2d0a848d8701;hp=ee1bc8121319943f49271b47b17e495ac92821de;hpb=3d1cf1e79073cdd9c0ecb09ee9e4f7dd29dc4149;p=8sync.git

diff --git a/loopy.scm b/loopy.scm
index ee1bc81..01c0b52 100644
--- a/loopy.scm
+++ b/loopy.scm
@@ -1,4 +1,4 @@
-(define-module (loopy agenda)
+(define-module (eightsync agenda)
   #:use-module (srfi srfi-1)
   #:use-module (srfi srfi-9)
   #:use-module (srfi srfi-9 gnu)
@@ -33,11 +33,18 @@
             schedule-segments-split schedule-extract-until!
             add-segments-contents-to-queue!
 
+            %sync 8sync %sync-at 8sync-at %sync-delay 8sync-delay
+
             <run-request>
             make-run-request run-request?
             run-request-proc run-request-when
 
-            run wrap run-wrap run-wrap-at
+            <port-request>
+            make-port-request port-request?
+            port-request-port
+            port-request-read port-request-write port-request-except
+
+            run-it wrap run run-at run-delay
 
             %current-agenda
             start-agenda agenda-run-once))
@@ -77,6 +84,9 @@
   (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
@@ -87,10 +97,21 @@
                       (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))))
+
 
 
 ;;; Schedule
@@ -110,6 +131,11 @@
   (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)
@@ -118,9 +144,14 @@
     (_ (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)
@@ -132,10 +163,12 @@
         (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)))
 
@@ -146,8 +179,12 @@
   (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)
 
@@ -167,19 +204,22 @@ Will produce (0 . 0) instead of a negative number, if needed."
         (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>
@@ -188,6 +228,7 @@ Will produce (0 . 0) instead of a negative number, if needed."
   (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)
@@ -202,6 +243,7 @@ Will produce (0 . 0) instead of a negative number, if needed."
 ;;   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
@@ -239,6 +281,7 @@ Will produce (0 . 0) instead of a negative number, if needed."
      (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)
@@ -285,36 +328,6 @@ Will produce (0 . 0) instead of a negative number, if needed."
    segments))
 
 
-
-;;; 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)))
-
-
 
 ;;; Request to run stuff
 ;;; ====================
@@ -325,18 +338,120 @@ Will produce (0 . 0) instead of a negative number, if needed."
   (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)))
+
+
+;; A request to set up a port with at least one of read, write, except
+;; handling processes
+
+(define-record-type <port-request>
+  (make-port-request-intern port read write except)
+  port-request?
+  (port port-request-port)
+  (read port-request-read)
+  (write port-request-write)
+  (except port-request-except))
+
+(define* (make-port-request port #:key read write except)
+  (if (not (or read write except))
+      (throw 'no-port-handler-given "No port handler given.\n"))
+  (make-port-request-intern port read write except))
+
+
+
+;;; 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.
+
+%sync 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! :)
+
+The % and 8 characters kind of look similar... hence this library's
+name!  (There are 8sync aliases if you prefer that name.)"
+  (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 ...))
+
+(define-syntax-rule (8sync args ...)
+  "Alias for %sync"
+  (%sync args ...))
+
+(define-syntax-rule (8sync-at args ...)
+  "Alias for %sync-at"
+  (%sync-at args ...))
+
+(define-syntax-rule (8sync-delay args ...)
+  "Alias for %sync-delay"
+  (8sync-delay args ...))
 
-(define-syntax-rule (run-wrap-at body ... when)
-  (run (wrap body ...) when))
 
 
 ;;; Execution of agenda, and current agenda
@@ -345,6 +460,7 @@ Will produce (0 . 0) instead of a negative number, if needed."
 (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)
@@ -356,11 +472,11 @@ Will produce (0 . 0) instead of a negative number, if needed."
         (cons 0 0))
        (soonest-time    ; ie, the agenda is non-empty
         (let* ((current-time (agenda-time agenda)))
-          (if (time<= (pk 'soonest-time soonest-time) (pk 'current-time current-time))
+          (if (time<= soonest-time current-time)
               ;; Well there's something due so let's select
               ;; (this avoids a (possible?) race condition chance)
               (cons 0 0)
-              (pk 'time-minus (time-minus soonest-time current-time)))))
+              (time-minus soonest-time current-time))))
        (else
         (cons #f #f)))))
   (define (do-select)
@@ -418,11 +534,24 @@ Will produce (0 . 0) instead of a negative number, if needed."
       (update-agenda)
       agenda))
 
+(define (agenda-handle-port-request! agenda port-request)
+  "Update an agenda for a port-request"
+  (define (handle-selector request-selector port-map-selector)
+    (if (request-selector port-request)
+        (hash-set! (port-map-selector agenda)
+                   (port-request-port port-request)
+                   (request-selector port-request))))
+  (handle-selector port-request-read agenda-read-port-map)
+  (handle-selector port-request-write agenda-write-port-map)
+  (handle-selector port-request-except agenda-except-port-map))
+
 
 (define* (start-agenda agenda
                        #: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
@@ -432,17 +561,20 @@ Will produce (0 . 0) instead of a negative number, if needed."
              (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))))))
 
@@ -454,8 +586,9 @@ based on the results"
         (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)))
@@ -479,19 +612,21 @@ based on the results"
                      (schedule-at! request-time (run-request-proc run-request)))
                     (#f
                      (enq! next-queue (run-request-proc run-request))))))))
+        (define (handle-individual result)
+          (match result
+            ((? run-request? new-proc)
+             (enqueue new-proc))
+            ((? port-request? port-request)
+             (agenda-handle-port-request! agenda port-request))
+            ;; do nothing
+            (_ #f)))
         ;; @@: 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
-          ((? run-request? new-proc)
-           (enqueue new-proc))
-          (((? run-request? new-procs) ...)
-           (for-each
-            (lambda (new-proc)
-              (enqueue new-proc))
-            new-procs))
-          ;; do nothing
-          (_ #f))))
+          ((results ...)
+           (for-each handle-individual results))
+          (one-result (handle-individual one-result)))))
     ;; 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