X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?a=blobdiff_plain;f=sam.scm;h=8e8a730e4a22b75084be5bc9867baf4c48208e24;hb=9253a20d269814e27a00a8766a0554856233a561;hp=431cd1c41ce9b9cac0e68843cc39ab80ab6aa3c8;hpb=2ddb195dc4dace1129e50e10c6992e2ae95fae83;p=sam.git diff --git a/sam.scm b/sam.scm index 431cd1c..8e8a730 100644 --- a/sam.scm +++ b/sam.scm @@ -5,62 +5,74 @@ (import (chicken io) (chicken string) + (chicken port) matchable srfi-18 ; threads - srfi-69 ; hashtable - udp6 - uri-generic) + srfi-69 ; hash-table + uuid ; ids for actors + uri-generic + udp + fifo) ;; Actors -(define (make-machine host port) - (cons host port)) -(define (machine-host m) (car m)) -(define (machine-port m) (cdr m)) +(define this-host "localhost") +(define this-port 8000) -(define this-machine (make-machine "localhost" 1234)) +(define (make-address host port id) + (make-uri #:scheme "actor" + #:host host + #:port port + #:path (list '/ id))) -(define next-actor-id 1) - -(define (address-id address) (car address)) -(define (address-machine address) (cdr address)) +(define (make-local-address . args) + (make-address this-host + this-port + (if (null? args) + (uuid) + (car args)))) + +(define (address-id address) (cadr (uri-path address))) (define (address-local? address) - (equal? (address-machine address) - this-machine)) + (and (equal? (uri-host address) this-host) + (equal? (uri-port address) this-port))) (define actor-table (make-hash-table)) (define (make-actor beh) - (let* ((id next-actor-id)) - (hash-table-put! id beh) - (cons id this-machine))) + (let* ((address (make-local-address)) + (id (address-id address))) + (hash-table-set! actor-table id beh) + address)) (define (deliver-message address . message) (let ((id (address-id address))) - (let ((behaviour (hash-table-ref/default actor-table id '())))) - (if (null? behaviour) - (print "Warning: discarded message" message " to unknown actor " address) - (match (apply (hash-table-ref actor-table id) (cons address message)) - ('done (hash-table-delete! actor-table actor)) - ('sleep 'do-nothing) - (new-beh (hash-table-put! actor new-beh)))))) + (let ((behaviour (hash-table-ref/default actor-table id '()))) + (if (null? behaviour) + (print "Warning: discarded message" message " to unknown actor " address) + (match (apply (hash-table-ref actor-table id) (cons address message)) + ('done (hash-table-delete! actor-table id)) + ('sleep 'do-nothing) + (new-beh (hash-table-set! actor-table id new-beh))))))) ;; Scheduler (define local-queue-mutex (make-mutex "message queue")) (define message-available-mutex (make-mutex "message available")) +(mutex-lock! message-available-mutex #f #f) (define local-queue (make-fifo)) (define (send-message address . message) (apply (if (address-local? address) send-local-message send-network-message) - message)) + (cons address message))) (define (send-local-message address . message) (mutex-lock! local-queue-mutex) (fifo-push local-queue (cons address message)) + (mutex-unlock! message-available-mutex) (mutex-unlock! local-queue-mutex)) (define (send-network-message address . message) @@ -75,20 +87,105 @@ (define (next-local-message) (let ((res #f)) + (mutex-lock! message-available-mutex #f #f) (mutex-lock! local-queue-mutex) - (set! res (if (fifo-empty? local-queue) - #f - (fifo-pop local-queue))) + (set! res (fifo-pop local-queue)) + (if (not (fifo-empty? local-queue)) + (mutex-unlock! message-available-mutex)) (mutex-unlock! local-queue-mutex) res)) -(define scheduler-thread - (make-thread +(define (start-scheduler) + (thread-start! (lambda () - (let loop ((next-addressed-message (next-local-message))) - (if next-addressed-message - (apply deliver-message next-addressed-message) - (begin - (lo)))))) + (let loop () + (apply deliver-message (next-local-message)) + (loop))))) + +;; Console + +(define reader-queue-mutex (make-mutex "reader queue")) +(define reader-available-mutex (make-mutex "reader available")) +(mutex-lock! reader-available-mutex #f #f) +(define reader-queue (make-fifo)) + +(define console + (make-actor (lambda (self . message) + (mutex-lock! reader-queue-mutex) + (fifo-push reader-queue (car message)) + (mutex-unlock! reader-available-mutex) + (mutex-unlock! reader-queue-mutex) + 'sleep))) + +(define (next-reader) + (let ((res #f)) + (mutex-lock! reader-available-mutex #f #f) + (mutex-lock! reader-queue-mutex) + (set! res (fifo-pop reader-queue)) + (if (not (fifo-empty? reader-queue)) + (mutex-unlock! reader-available-mutex)) + (mutex-unlock! reader-queue-mutex) + res)) + +(define (start-console) + (let loop () + (let ((reader (next-reader))) + (##sys#thread-block-for-i/o! (current-thread) 0 #t) + (thread-yield!) + (send-message reader (read-line))) + (loop))) - (thread-start!)) + +;; Network + +(define (start-network-listener) + (thread-start! + (lambda () + (let ((s (udp-open-socket*))) + (udp-bind! s #f this-port) + (let loop () + (let-values (((n str) (udp-recv s 1024))) + (print "Received " n " bytes over network: " str) + (match (with-input-from-string str read) + ((uri-str message ...) + (apply send-message (cons (uri-reference uri-str) message))) + (else + (print "Warning: received badly formatted message string '" str "'")))) + (loop)))))) + +;; System interface + +(define system + (make-actor (lambda (self . message) + (match message + (('shutdown) + (print "## System actor received shutdown message.") + (exit 0) + 'done) + (('println strings ...) + (apply print strings) + 'sleep))))) + +;; Testing + + +(send-message system 'println "Hello, what is your name?") +(send-message console + (make-actor (lambda (self . message) + (match message + ((name) + (send-message system 'println "Hello, " name "!") + 'done))))) + +(thread-start! + (lambda () + (thread-sleep! 120) + (send-message system 'shutdown))) + +(print (uri->string system)) + +(start-scheduler) +(start-network-listener) +(start-console) + +;; (thread-join! scheduler-thread)