154 lines
5.8 KiB
Racket
154 lines
5.8 KiB
Racket
#lang syndicate
|
|
;;; SPDX-License-Identifier: LGPL-3.0-or-later
|
|
;;; SPDX-FileCopyrightText: Copyright © 2021 Tony Garnock-Jones <tonyg@leastfixedpoint.com>
|
|
|
|
(provide (all-from-out syndicate/schemas/gen/tcp)
|
|
spawn-tcp-driver
|
|
accept-connection
|
|
establish-connection
|
|
send-data
|
|
|
|
read-bytes-avail)
|
|
|
|
(require racket/tcp)
|
|
(require (only-in racket/exn exn->string))
|
|
(require syndicate/driver-support)
|
|
(require syndicate/schemas/gen/tcp)
|
|
(require syndicate/schemas/gen/dataspace-patterns)
|
|
|
|
(define-logger syndicate/drivers/tcp)
|
|
|
|
(define (spawn-tcp-driver ds)
|
|
(spawn
|
|
#:name 'tcp-driver
|
|
#:daemon? #t
|
|
|
|
(at ds
|
|
(during/spawn
|
|
(Observe (:pattern (Connection ,_ (TcpInbound ,(DLit $host) ,(DLit $port)))) _)
|
|
#:name (TcpInbound host port)
|
|
(run-listener ds host port))
|
|
|
|
(during/spawn
|
|
(Connection $local-peer (TcpOutbound $host $port))
|
|
#:name (TcpOutbound host port)
|
|
(run-outbound ds local-peer host port)))))
|
|
|
|
(define (run-listener ds host port)
|
|
(on-start (log-syndicate/drivers/tcp-info "+listener on ~v ~v" host port))
|
|
(on-stop (log-syndicate/drivers/tcp-info "-listener on ~v ~v" host port))
|
|
(linked-thread
|
|
#:name (list (TcpInbound host port) 'thread)
|
|
(lambda (facet)
|
|
(define listener (tcp-listen port 512 #t host))
|
|
(let loop ()
|
|
(define connection-custodian (make-custodian))
|
|
(define-values (i o) (parameterize ((current-custodian connection-custodian))
|
|
(tcp-accept listener)))
|
|
(turn! facet
|
|
(lambda () (spawn-inbound ds connection-custodian i o (TcpInbound host port))))
|
|
(loop)))))
|
|
|
|
(define (run-outbound ds local-peer host port)
|
|
(define connection-custodian (make-custodian))
|
|
((with-handlers ([exn:fail:network?
|
|
(lambda (e)
|
|
(lambda () (at local-peer (assert (ActiveSocket-close (exn->string e))))))])
|
|
(define-values (i o) (parameterize ((current-custodian connection-custodian))
|
|
(tcp-connect host port)))
|
|
(lambda ()
|
|
(define name (call-with-values (lambda () (tcp-addresses i #t)) list))
|
|
(on-stop (close-input-port i)
|
|
(close-output-port o))
|
|
(start-inbound-relay connection-custodian name local-peer i)
|
|
(define relay (outbound-relay name o))
|
|
(at local-peer
|
|
(assert (ActiveSocket-controller
|
|
(object #:name (list name 'socket)
|
|
[#:asserted (Socket data) (relay data)]))))))))
|
|
|
|
(define (spawn-inbound ds custodian i o spec)
|
|
(define name (call-with-values (lambda () (tcp-addresses i #t)) list))
|
|
(spawn
|
|
#:name name
|
|
(on-stop (close-input-port i)
|
|
(close-output-port o))
|
|
|
|
(define active-controller #f)
|
|
(define relay (outbound-relay name o))
|
|
(at ds
|
|
(assert (Connection
|
|
(object
|
|
#:name (list name 'active-socket)
|
|
[#:asserted (ActiveSocket-controller controller)
|
|
(log-syndicate/drivers/tcp-debug "~v controller for ~v" controller this-actor)
|
|
(when (not active-controller)
|
|
(start-inbound-relay custodian name controller i))
|
|
(set! active-controller controller)
|
|
#:retracted
|
|
(when (eq? controller active-controller)
|
|
(log-syndicate/drivers/tcp-debug "peer withdrawn ~v" this-actor)
|
|
(stop-current-facet))]
|
|
[#:asserted (ActiveSocket-close message)
|
|
(log-syndicate/drivers/tcp-debug "closing ~v:\n~a" this-actor message)
|
|
(stop-current-facet)]
|
|
[#:asserted (ActiveSocket-Socket (Socket data))
|
|
(relay data)])
|
|
spec)))))
|
|
|
|
(define (start-inbound-relay custodian name target i)
|
|
(linked-thread
|
|
#:name (list name 'input-thread)
|
|
#:custodian custodian
|
|
(lambda (facet)
|
|
(let loop ()
|
|
(define bs (read-bytes-avail i))
|
|
(when (bytes? bs)
|
|
(log-syndicate/drivers/tcp-debug "inbound data ~v for ~v" bs name)
|
|
(turn! facet (lambda () (send-data target bs)))
|
|
(loop))))))
|
|
|
|
(define (outbound-relay name o)
|
|
(define flush-pending #f)
|
|
(lambda (payload)
|
|
(log-syndicate/drivers/tcp-debug "outbound data ~v for ~v" payload name)
|
|
(write-bytes payload o)
|
|
(when (not flush-pending)
|
|
(set! flush-pending #t)
|
|
(facet-on-end-of-turn! this-facet
|
|
(lambda ()
|
|
(set! flush-pending #f)
|
|
(flush-output o))))))
|
|
|
|
(define (read-bytes-avail input-port #:limit [limit 65536])
|
|
(define buffer (make-bytes limit))
|
|
(match (read-bytes-avail! buffer input-port)
|
|
[(? number? count) (subbytes buffer 0 count)]
|
|
[other other]))
|
|
|
|
(define (accept-connection conn #:on-data on-data)
|
|
(at conn
|
|
(assert (ActiveSocket-controller
|
|
(object #:name 'inbound-socket-controller
|
|
[#:asserted (Socket data) (on-data data)])))))
|
|
|
|
(define (establish-connection ds spec
|
|
#:on-connected on-connected
|
|
#:on-data on-data
|
|
#:on-disconnected [on-disconnected (lambda () (stop-current-facet))]
|
|
#:on-rejected [on-rejected (lambda () (stop-current-facet))])
|
|
(define s
|
|
(object #:name 'outbound-socket
|
|
[#:asserted (ActiveSocket-controller peer)
|
|
(on-connected peer)
|
|
#:retracted
|
|
(on-disconnected)]
|
|
[#:asserted (ActiveSocket-close message)
|
|
(on-rejected message)]
|
|
[#:asserted (ActiveSocket-Socket (Socket data))
|
|
(on-data data)]))
|
|
(at ds (assert (Connection s spec))))
|
|
|
|
(define (send-data conn data)
|
|
(send! conn (Socket (if (bytes? data) data (string->bytes/utf-8 data)))))
|