actors: Generalize the <-foo methods functionality into send-message.
[8sync.git] / 8sync / actors.scm
index c694c489992abd9a99a9aca57f2afc605103e822..b651d553232742f263b511c7cf76212b0d32b9c6 100644 (file)
 ;;; See: https://web.archive.org/web/20081223021934/http://mumble.net/~jar/articles/oo-moon-weinreb.html
 ;;;   (also worth seeing: http://mumble.net/~jar/articles/oo.html )
 
+;; This is the internal, generalized message sending method.
+;; Users shouldn't use it!  Use the <-foo forms instead.
+
+;; @@: Could we get rid of some of the conditional checks through
+;;   some macro-foo?
+(define-inlinable (send-message xtra-params from-actor to-id action
+                                replying-to-message wants-reply?
+                                message-body-args)
+  (if replying-to-message
+      (set-message-replied! replying-to-message #t))
+  (let* ((hive (actor-hive from-actor))
+         (new-message
+          (make-message (hive-gen-message-id hive) to-id
+                        (actor-id from-actor) action
+                        message-body-args
+                        #:wants-reply wants-reply?
+                        #:in-reply-to
+                        (if replying-to-message
+                            (message-id replying-to-message)
+                            #f))))
+    ;; TODO: add xtra-params to both of these
+    (if wants-reply?
+        (abort-to-prompt (hive-prompt (actor-hive from-actor))
+                         from-actor new-message)
+        (8sync (hive-process-message hive new-message)))))
+
+
 (define (<- from-actor to-id action . message-body-args)
   "Send a message from an actor to another actor"
-  (let* ((hive (actor-hive from-actor))
-         (message (make-message (hive-gen-message-id hive) to-id
-                                (actor-id from-actor) action
-                                message-body-args)))
-    (8sync (hive-process-message hive message))))
+  (send-message '() from-actor to-id action
+                #f #f message-body-args))
 
 (define (<-wait from-actor to-id action . message-body-args)
   "Send a message from an actor to another, but wait until we get a response"
-  (let* ((hive (actor-hive from-actor))
-         (abort-to (hive-prompt (actor-hive from-actor)))
-         (message (make-message (hive-gen-message-id hive) to-id
-                                (actor-id from-actor) action
-                                message-body-args
-                                #:wants-reply #t)))
-    (abort-to-prompt abort-to from-actor message)))
+  (send-message '() from-actor to-id action
+                #f #t message-body-args))
 
 ;; TODO: Intelligently ~propagate(ish) errors on -wait functions.
 ;;   We might have `send-message-wait-brazen' to allow callers to
 
 (define (<-reply from-actor original-message . message-body-args)
   "Reply to a message"
-  (set-message-replied! original-message #t)
-  (let* ((hive (actor-hive from-actor))
-         (new-message (make-message (hive-gen-message-id hive)
-                                    (message-from original-message)
-                                    (actor-id from-actor) '*reply*
-                                    message-body-args
-                                    #:in-reply-to (message-id original-message))))
-    (8sync (hive-process-message hive new-message))))
+  (send-message '() from-actor (message-from original-message) '*reply*
+                original-message #f message-body-args))
 
 (define (<-auto-reply from-actor original-message)
   "Auto-reply to a message.  Internal use only!"
-  (set-message-replied! original-message #t)
-  (let* ((hive (actor-hive from-actor))
-         (new-message (make-message (hive-gen-message-id hive)
-                                    (message-from original-message)
-                                    (actor-id from-actor) '*auto-reply*
-                                    '()
-                                    #:in-reply-to (message-id original-message))))
-    (8sync (hive-process-message hive new-message))))
+  (send-message '() from-actor (message-from original-message) '*auto-reply*
+                original-message #f '()))
 
 (define (<-reply-wait from-actor original-message . message-body-args)
   "Reply to a messsage, but wait until we get a response"
-  (set-message-replied! original-message #t)
-  (let* ((hive (actor-hive from-actor))
-         (abort-to (hive-prompt (actor-hive from-actor)))
-         (new-message (make-message (hive-gen-message-id hive)
-                                    (message-from original-message)
-                                    (actor-id from-actor) '*reply*
-                                    message-body-args
-                                    #:wants-reply #t
-                                    #:in-reply-to (message-id original-message))))
-    (abort-to-prompt abort-to from-actor new-message)))
+  (send-message '() from-actor (message-from original-message) '*reply*
+                original-message #t message-body-args))
 
 
 \f
@@ -512,45 +511,50 @@ to come after class definition."
              result))))))
 
   (define (resume-waiting-coroutine)
-    (cond
-     ((or (eq? (message-action message) '*reply*)
-          (eq? (message-action message) '*auto-reply*))
-      (call-catching-coroutine
-       (lambda ()
-         (match (hash-remove! (hive-waiting-coroutines hive)
-                              (message-in-reply-to message))
-           ((_ . (resume-actor-id . kont))
-            (if (not (equal? (message-to message)
-                             resume-actor-id))
-                (throw 'resuming-to-wrong-actor
-                       "Attempted to resume a coroutine to the wrong actor!"
-                       #:expected-actor-id (message-to message)
-                       #:got-actor-id resume-actor-id
-                       #:message message))
-            (let (;; @@: How should we resolve resuming coroutines to actors who are
-                  ;;   now gone?
-                  (actor (resolve-actor-to))
-                  (result (kont message)))
-              (maybe-autoreply actor)
-              result))
-           (#f (throw 'no-waiting-coroutine
-                      "message in-reply-to tries to resume nonexistent coroutine"
-                      message))))))
-     ;; Yikes, we must have gotten an error or something back
-     (else
-      ;; @@: Not what we want in the long run?
-      ;; What we'd *prefer* to do is to resume this message
-      ;; and throw an error inside the message handler
-      ;; (say, from send-mesage-wait), but that causes a SIGABRT (??!!)
-      (hash-remove! (hive-waiting-coroutines hive)
-                    (message-in-reply-to message))
-      (let ((explaination
-             (if (eq? (message-action message) '*reply*)
-                 "Won't resume coroutine; got an *error* as a reply"
-                 "Won't resume coroutine because action is not *reply*")))
-        (throw 'hive-unresumable-coroutine
-               explaination
-               #:message message)))))
+    (case (message-action message)
+      ;; standard reply / auto-reply
+      ((*reply* *auto-reply*)
+       (call-catching-coroutine
+        (lambda ()
+          (match (hash-remove! (hive-waiting-coroutines hive)
+                               (message-in-reply-to message))
+            ((_ . (resume-actor-id . kont))
+             (if (not (equal? (message-to message)
+                              resume-actor-id))
+                 (throw 'resuming-to-wrong-actor
+                        "Attempted to resume a coroutine to the wrong actor!"
+                        #:expected-actor-id (message-to message)
+                        #:got-actor-id resume-actor-id
+                        #:message message))
+             (let (;; @@: How should we resolve resuming coroutines to actors who are
+                   ;;   now gone?
+                   (actor (resolve-actor-to))
+                   (result (kont message)))
+               (maybe-autoreply actor)
+               result))
+            (#f (throw 'no-waiting-coroutine
+                       "message in-reply-to tries to resume nonexistent coroutine"
+                       message))))))
+      ;; Yikes, an error!
+      ((*error*)
+       ;; @@: Not what we want in the long run?
+       ;; What we'd *prefer* to do is to resume this message
+       ;; and throw an error inside the message handler
+       ;; (say, from send-mesage-wait), but that causes a SIGABRT (??!!)
+       (hash-remove! (hive-waiting-coroutines hive)
+                     (message-in-reply-to message))
+       (let ((explaination
+              (if (eq? (message-action message) '*reply*)
+                  "Won't resume coroutine; got an *error* as a reply"
+                  "Won't resume coroutine because action is not *reply*")))
+         (throw 'hive-unresumable-coroutine
+                explaination #:message message)))
+      ;; Unhandled action for a reply!
+      (else
+       (throw 'hive-unresumable-coroutine
+              "Won't resume coroutine, nonsense action on reply message"
+              #:action (message-action message)
+              #:message message))))
 
   (define (process-remote-message)
     ;; Find the ambassador