From: Christopher Allan Webber Date: Thu, 8 Dec 2016 18:47:32 +0000 (-0600) Subject: agenda: Use suspendable ports feature from Guile 2.2. X-Git-Tag: v0.3.0~33 X-Git-Url: https://jxself.org/git/?a=commitdiff_plain;h=64099f71e0d685260289229a599a753923d2dc8f;p=8sync.git agenda: Use suspendable ports feature from Guile 2.2. This removes the old method of watching for when ports are updated via select and explicitly calling a particular function, and instead can simply suspend at the appropriate points using Guile's common I/O procedures; the agenda handles waking things up when they're ready. * 8sync/agenda.scm: Import `(ice-9 suspendable-ports)' and run install-suspendable-ports! (, agenda-except-port-map, make-agenda): Drop except-port-map from agenda. The "meaning" of read-port-map and write-port-map has changed a bit too; these are still a hash-table of a port to a procedure to be called when that port is available, but after being selected, items are removed from the table. (, make-port-request, port-request, ) (port-remove-request, 8sync-port, 8sync-port-remove) (agenda-handle-port-request!, agenda-handle-port-remove-request!): Remove. (8sync-nowait): Move comment that was previously in 8sync-port here. (update-agenda-from-select!): Update to use the new "meaning" of the agenda-read-port-map and agenda-write-port-map and to drop referencing the deprecated agenda-except-port-map. Properly removes items from the read and write maps once they've been selected. (, , agenda-handle-read-request) (agenda-handle-write-request, wait-for-readable, wait-for-writable): New variables. (stop-on-nothing-to-do): Remove check on removed agenda-except-port-map. (agenda-run-once): Parameterize the current-read-waiter and current-write-waiter to wait-for-readable and wait-for-writable respectively. Update handle-individual to use the new and types. --- diff --git a/8sync/agenda.scm b/8sync/agenda.scm index e747899..f22134d 100644 --- a/8sync/agenda.scm +++ b/8sync/agenda.scm @@ -23,6 +23,7 @@ #:use-module (ice-9 q) #:use-module (ice-9 match) #:use-module (ice-9 receive) + #:use-module (ice-9 suspendable-ports) #:export ( make-agenda agenda? agenda-queue agenda-prompt-tag @@ -57,20 +58,10 @@ make-run-request run-request? run-request-proc run-request-when - - make-port-request port-request port-request? - port-request-port - port-request-read port-request-write port-request-except - - - make-port-remove-request port-remove-request port-remove-request? - port-remove-request-port - run-it wrap wrap-apply run run-at run-delay 8sync 8sync-delay 8sync-run 8sync-run-at 8sync-run-delay - 8sync-port 8sync-port-remove 8sync-nowait 8sleep @@ -89,6 +80,8 @@ %current-agenda start-agenda agenda-run-once)) +(install-suspendable-ports!) + ;; @@: Using immutable agendas here, so wouldn't it make sense to ;; replace this queue stuff with using pfds based immutable queues? @@ -112,14 +105,13 @@ (define-immutable-record-type (make-agenda-intern queue prompt-tag - read-port-map write-port-map except-port-map + read-port-map write-port-map schedule time catch-handler pre-unwind-handler) agenda? (queue agenda-queue) (prompt-tag agenda-prompt-tag) (read-port-map agenda-read-port-map) (write-port-map agenda-write-port-map) - (except-port-map agenda-except-port-map) (schedule agenda-schedule) (time agenda-time) (catch-handler agenda-catch-handler) @@ -136,7 +128,6 @@ Generally done automatically for the user through (make-agenda)." (prompt (make-prompt-tag)) (read-port-map (make-hash-table)) (write-port-map (make-hash-table)) - (except-port-map (make-hash-table)) (schedule (make-schedule)) (time (gettimeofday)) (catch-handler #f) @@ -144,7 +135,7 @@ Generally done automatically for the user through (make-agenda)." ;; TODO: document arguments "Make a fresh agenda." (make-agenda-intern queue prompt - read-port-map write-port-map except-port-map + read-port-map write-port-map schedule time catch-handler pre-unwind-handler)) @@ -443,32 +434,6 @@ Will produce (0 . 0) instead of a negative number, if needed." (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 - (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)) - -(define port-request make-port-request) - -(define-record-type - (make-port-remove-request port) - port-remove-request? - (port port-remove-request-port)) - -(define port-remove-request make-port-remove-request) - - ;;; Asynchronous escape to run things ;;; ================================= @@ -572,27 +537,6 @@ Possibly specify WHEN as the second argument." (define-syntax-rule (8sync-delay args ...) (8sync-run-delay args ...)) -(define-syntax-rule (8sync-port port port-request-args ...) - (8sync-abort-to-prompt - (make-async-request - (lambda (kont) - (list (make-port-request port port-request-args ...) - (make-run-request - ;; What's with returning #f to kont? - ;; Otherwise we sometimes get errors like - ;; "Zero values returned to single-valued continuation"" - (wrap (kont #f)) #f)))))) - -(define-syntax-rule (8sync-port-remove port) - (8sync-abort-to-prompt - (make-async-request - (lambda (kont) - (list (make-port-remove-request port) - (make-run-request - ;; See comment in 8sync-port - (wrap (kont #f)) #f)))))) - - ;; TODO: Write (%run-immediately) (define-syntax-rule (8sync-nowait body) @@ -602,7 +546,9 @@ forge ahead in our current function!" (make-async-request (lambda (kont) (list (make-run-request - ;; See comment in 8sync-port + ;; What's with returning #f to kont? + ;; Otherwise we sometimes get errors like + ;; "Zero values returned to single-valued continuation"" (wrap (kont #f)) #f) (make-run-request (lambda () body) #f)))))) @@ -660,7 +606,7 @@ Also handles sleeping when all we have to do is wait on the schedule." (lambda () (select (hash-keys (agenda-read-port-map agenda)) (hash-keys (agenda-write-port-map agenda)) - (hash-keys (agenda-except-port-map agenda)) + '() sec usec)) (lambda (key . rest-args) (match rest-args @@ -672,23 +618,20 @@ Also handles sleeping when all we have to do is wait on the schedule." (lambda (initial-procs) (fold (lambda (port prev) - (cons (lambda () - ((hash-ref port-map port) port)) - prev)) + (define proc (hashq-ref port-map port)) + ;; Now that we've selected on this port, it can be removed + (hashq-remove! port-map port) + (cons proc prev)) initial-procs ports))) (match (do-select) - ((read-ports write-ports except-ports) - ;; @@: Come on, we can do better than append ;P + ((read-ports write-ports except-ports) ; except-ports not used ((compose (ports->procs read-ports (agenda-read-port-map agenda)) (ports->procs write-ports - (agenda-write-port-map agenda)) - (ports->procs - except-ports - (agenda-except-port-map agenda))) + (agenda-write-port-map agenda))) '())))) (define (update-agenda) (let ((procs-to-run (get-procs-to-run)) @@ -716,33 +659,35 @@ Also handles sleeping when all we have to do is wait on the schedule." (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) - ;; @@: Should we remove if #f? - (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 (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-record-type + (make-read-request port proc) + read-request? + (port read-request-port) + (proc read-request-proc)) + +(define-record-type + (make-write-request port proc) + write-request? + (port write-request-port) + (proc write-request-proc)) + +(define (agenda-handle-read-request! agenda read-request) + "Handle , which is a request to add this port to the poll/select +on suspendable ports." + (hashq-set! (agenda-read-port-map agenda) + (read-request-port read-request) + (read-request-proc read-request))) + +(define (agenda-handle-write-request! agenda write-request) + (hashq-set! (agenda-write-port-map agenda) + (write-request-port write-request) + (write-request-proc write-request))) (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))))) + (= 0 (hash-count (const #t) (agenda-write-port-map agenda))))) (define* (start-agenda agenda @@ -822,6 +767,20 @@ Also handles sleeping when all we have to do is wait on the schedule." (or pre-unwind-handler (lambda _ #f))) (begin body ...))) +(define (wait-for-readable port) + (display "Waiting to read\n") + (8sync-abort-to-prompt + (make-async-request + (lambda (kont) + (make-read-request port (wrap (kont #f))))))) + +(define (wait-for-writable port) + (display "Waiting to write\n") + (8sync-abort-to-prompt + (make-async-request + (lambda (kont) + (make-write-request port (wrap (kont #f))))))) + (define (agenda-run-once agenda) "Run once through the agenda, and produce a new agenda based on the results" @@ -829,7 +788,11 @@ based on the results" (call-with-prompt (agenda-prompt-tag agenda) (lambda () - (parameterize ((%current-agenda agenda)) + (parameterize ((%current-agenda agenda) + ;; @@: Couldn't we just parameterize this at the start of + ;; the agenda...? + (current-read-waiter wait-for-readable) + (current-write-waiter wait-for-writable)) (maybe-catch-all ((agenda-catch-handler agenda) (agenda-pre-unwind-handler agenda)) @@ -864,11 +827,12 @@ based on the results" (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)) + ((? read-request? read-request) + (agenda-handle-read-request! agenda read-request)) + ((? write-request? write-request) + (agenda-handle-write-request! agenda write-request)) ;; do nothing + ;; @@: Why not throw an error? (_ #f))) ;; @@: We might support delay-wrapped procedures here (match proc-result