-(define-module (loopy agenda)
+;; Copyright (C) 2015 Christopher Allan Webber <cwebber@dustycloud.org>
+
+;; This library is free software; you can redistribute it and/or
+;; modify it under the terms of the GNU Lesser General Public
+;; License as published by the Free Software Foundation; either
+;; version 3 of the License, or (at your option) any later version.
+;;
+;; This library is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+;; Lesser General Public License for more details.
+;;
+;; You should have received a copy of the GNU Lesser General Public
+;; License along with this library; if not, write to the Free Software
+;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+;; 02110-1301 USA
+
+(define-module (eightsync agenda)
#:use-module (srfi srfi-1)
#:use-module (srfi srfi-9)
#:use-module (srfi srfi-9 gnu)
schedule-segments-split schedule-extract-until!
add-segments-contents-to-queue!
+ %sync 8sync
+
<run-request>
make-run-request run-request?
run-request-proc run-request-when
+ <port-request>
+ make-port-request port-request port-request?
+ port-request-port
+ port-request-read port-request-write port-request-except
+
run-it wrap run run-at run-delay
+ %port-request %run %run-at %run-delay
+ 8port-request 8run 8run-at 8run-delay
+
%current-agenda
start-agenda agenda-run-once))
;;; Request to run stuff
;;; ====================
-(define-immutable-record-type <run-request>
+(define-record-type <run-request>
(make-run-request proc when)
run-request?
(proc run-request-proc)
(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))
+
+(define port-request make-port-request)
+
+
\f
;;; Asynchronous escape to run things
;;; =================================
(make-future call-first on-success on-fail on-error)
when))
-(define-syntax-rule (async body args ...)
- (abort-to-prompt (current-agenda-prompt)
- (wrap body)
- args ...))
+(define-syntax-rule (%sync async-request)
+ "Run BODY asynchronously at a prompt, passing args to make-future.
-(define-syntax-rule (async-at body when args ...)
- (abort-to-prompt (current-agenda-prompt)
- (wrap body)
- (append (list #:when when)
- args ...)))
+Pronounced `eight-sync' despite the spelling.
-(define-syntax-rule (async-delay body delay-time args ...)
+%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! (That, and the pun 'eight-synchronous' programming.)
+There are 8sync aliases if you prefer that name."
(abort-to-prompt (current-agenda-prompt)
- (wrap body)
- (append (list #:when (tdelta delay-time))
- args ...)))
+ async-request))
+
+(define-syntax-rule (8sync args ...)
+ "Alias for %sync"
+ (%sync args ...))
+
+;; Async port request and run-request meta-requests
+(define (make-async-request proc)
+ "Wrap PROC in an async-request
+
+The purpose of this is to make sure that users don't accidentally
+return the wrong thing via (8sync) and trip themselves up."
+ (cons '*async-request* proc))
+
+(define (setup-async-request resume-kont async-request)
+ "Complete an async request for agenda-run-once's continuation handling"
+ (match async-request
+ (('*async-request* . async-setup-proc)
+ (async-setup-proc resume-kont))
+ ;; TODO: deliver more helpful errors depending on what the user
+ ;; returned
+ (_ (throw 'invalid-async-request
+ "Invalid request passed back via an (%sync) procedure."
+ async-request))))
+
+(define-syntax-rule (%run body ...)
+ (%run-at body ... #f))
+
+(define-syntax-rule (%run-at body ... when)
+ (make-async-request
+ (lambda (kont)
+ (make-run-request
+ (wrap
+ (kont
+ (begin body ...)))
+ when))))
+
+(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 ...)
+ (make-async-request
+ (lambda (kont)
+ (list (make-port-request port-request-args ...)
+ (make-run-request kont)))))
+
+;; TODO
+(define-syntax-rule (%run-with-return return body ...)
+ (make-async-request
+ (lambda (kont)
+ (let ((return kont))
+ (lambda ()
+ body ...)))))
+
+;; Aliases
+(define-syntax-rule (8run args ...) (%run args ...))
+(define-syntax-rule (8run-at args ...) (%run-at args ...))
+(define-syntax-rule (8run-delay args ...) (%run-delay args ...))
+(define-syntax-rule (8port-request args ...) (%port-request args ...))
+
\f
;;; Execution of agenda, and current agenda
(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
;; @@: Hm, maybe here would be a great place to handle
;; select'ing on ports.
;; We could compose over agenda-run-once and agenda-read-ports
- (parameterize ((%current-agenda agenda))
- (agenda-run-once agenda))))
+ (agenda-run-once agenda)))
(if (and stop-condition (stop-condition agenda))
'done
(let* ((agenda
based on the results"
(define (call-proc proc)
(call-with-prompt
- (agenda-prompt-tag agenda)
- (lambda ()
- (proc))
- (lambda* (resume-with please-run-this . args)
- (apply request-future please-run-this resume-with
- args))))
+ (agenda-prompt-tag agenda)
+ (lambda ()
+ (parameterize ((%current-agenda agenda))
+ (proc)))
+ (lambda (kont async-request)
+ (setup-async-request kont async-request))))
(let ((queue (agenda-queue agenda))
(next-queue (make-q)))
(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
projects / 8sync.git / blobdiff