agenda: Various %port-foo enhancements

[8sync.git] / 8sync / agenda.scm

diff --git a/8sync/agenda.scm b/8sync/agenda.scm
index c2614ef471cef514b14f3a7878a1523ea453c603..da398458db34096d2893d61286456ee9ad156ab1 100644 (file)
--- a/8sync/agenda.scm
+++ b/8sync/agenda.scm
@@ -64,9 +64,15 @@
             port-request-port
             port-request-read port-request-write port-request-except
 
+            <port-remove-request>
+            make-port-remove-request port-remove-request port-remove-request?
+            port-remove-request-port
+
             run-it wrap wrap-apply run run-at run-delay
 
-            %port-request %run %run-at %run-delay
+            %run %run-at %run-delay %port-request %port-remove-request
+            %8sync-run %8sync-run-at %8sync-run-delay
+            %8sync-port %8sync-port-remove
             
             catch-8sync catch-%8sync
 
@@ -78,6 +84,8 @@
 
             print-error-and-continue
 
+            stop-on-nothing-to-do
+
             %current-agenda
             start-agenda agenda-run-once))
 
@@ -453,6 +461,13 @@ Will produce (0 . 0) instead of a negative number, if needed."
 
 (define port-request make-port-request)
 
+(define-record-type <port-remove-request>
+  (make-port-remove-request port)
+  port-remove-request?
+  (port port-remove-request-port))
+
+(define port-remove-request make-port-remove-request)
+
 
 \f
 ;;; Asynchronous escape to run things
@@ -546,11 +561,42 @@ return the wrong thing via (%8sync) and trip themselves up."
 (define-syntax-rule (%run-delay body ... delay-time)
   (%run-at body ... (tdelta delay-time)))
 
-(define-syntax-rule (%port-request add-this-port port-request-args ...)
+(define-syntax-rule (%port-request port port-request-args ...)
   (make-async-request
    (lambda (kont)
-     (list (make-port-request port-request-args ...)
-           (make-run-request kont)))))
+     (list (make-port-request port port-request-args ...)
+           (make-run-request kont #f)))))
+
+(define-syntax-rule (%port-remove-request port)
+  (make-async-request
+   (lambda (kont)
+     (list (make-port-remove-request port)
+           (make-run-request kont #f)))))
+
+
+;; Sugar
+(define-syntax-rule (%8sync-run rest ...)
+  "Sugar for (%8sync (%run ...))"
+  (%8sync (%run rest ...)))
+
+(define-syntax-rule (%8sync-run-at rest ...)
+  "Sugar for (%8sync (%run-at ...))"
+  (%8sync (%run-at rest ...)))
+
+(define-syntax-rule (%8sync-run-delay rest ...)
+  "Sugar for (%8sync (%run-delay ...))"
+  (%8sync (%run-delay rest ...)))
+
+(define-syntax-rule (%8sync-port rest ...)
+  "Sugar for (%8sync (%port-request ...))"
+  (%8sync (%port-request rest ...)))
+
+(define-syntax-rule (%8sync-port-remove rest ...)
+  "Sugar for (%8sync (%port-remove-request ...))"
+  (%8sync (%port-remove-request rest ...)))
+
+
+;; TODO: Write (%run-immediately)
 
 ;; TODO
 (define-syntax-rule (%run-with-return return body ...)
@@ -584,7 +630,9 @@ return the wrong thing via (%8sync) and trip themselves up."
 (define %current-agenda (make-parameter #f))
 
 (define (update-agenda-from-select! agenda)
-  "Potentially (select) on ports specified in agenda, adding items to queue"
+  "Potentially (select) on ports specified in agenda, adding items to queue.
+
+Also handles sleeping when all we have to do is wait on the schedule."
   (define (hash-keys hash)
     (hash-map->list (lambda (k v) k) hash))
   (define (get-wait-time)
@@ -661,7 +709,9 @@ return the wrong thing via (%8sync) and trip themselves up."
         (has-items? agenda-write-port-map)
         (has-items? agenda-except-port-map)))
 
-  (if (ports-to-select?)
+  (if (or (ports-to-select?)
+          ;; select doubles as sleep...
+          (not (schedule-empty? (agenda-schedule agenda)))) 
       (update-agenda)
       agenda))
 
@@ -669,6 +719,7 @@ return the wrong thing via (%8sync) and trip themselves up."
   "Update an agenda for a port-request"
   (define (handle-selector request-selector port-map-selector)
     (if (request-selector port-request)
+        ;; @@: Should we remove if #f?
         (hash-set! (port-map-selector agenda)
                    (port-request-port port-request)
                    (request-selector port-request))))
@@ -677,8 +728,27 @@ return the wrong thing via (%8sync) and trip themselves up."
   (handle-selector port-request-except agenda-except-port-map))
 
 
+(define (agenda-handle-port-remove-request! agenda port-remove-request)
+  "Update an agenda for a port-remove-request"
+  (let ((port (port-remove-request-port port-remove-request)))
+    (hash-remove! (agenda-read-port-map agenda) port)
+    (hash-remove! (agenda-write-port-map agenda) port)
+    (hash-remove! (agenda-except-port-map agenda) port)))
+
+
+(define (stop-on-nothing-to-do agenda)
+  (and (q-empty? (agenda-queue agenda))
+       (schedule-empty? (agenda-schedule agenda))
+       (= 0 (hash-count (const #t) (agenda-read-port-map agenda)))
+       (= 0 (hash-count (const #t) (agenda-write-port-map agenda)))
+       (= 0 (hash-count (const #t) (agenda-except-port-map agenda)))))
+
+
 (define* (start-agenda agenda
-                       #:key stop-condition
+                       #:key
+                       ;; @@: Should we make stop-on-nothing-to-do
+                       ;;   the default stop-condition?
+                       stop-condition
                        (get-time gettimeofday)
                        (handle-ports update-agenda-from-select!))
   ;; TODO: Document fields
@@ -708,6 +778,7 @@ return the wrong thing via (%8sync) and trip themselves up."
              (agenda-queue agenda))
             (loop agenda))))))
 
+
 (define (print-error-and-continue key . args)
   "Frequently used as pre-unwind-handler for agenda"
   (cond
@@ -781,11 +852,14 @@ based on the results"
                     (#f
                      (enq! next-queue (run-request-proc run-request))))))))
         (define (handle-individual result)
+          ;; @@: Could maybe optimize by switching to an explicit cond...
           (match result
             ((? run-request? new-proc)
              (enqueue new-proc))
             ((? port-request? port-request)
              (agenda-handle-port-request! agenda port-request))
+            ((? port-remove-request? port-remove-request)
+             (agenda-handle-port-remove-request! agenda port-remove-request))
             ;; do nothing
             (_ #f)))
         ;; @@: We might support delay-wrapped procedures here