racket/collects/web-server/private/connection-manager.ss
2008-02-24 21:27:36 +00:00

61 lines
2.0 KiB
Scheme

#lang scheme/base
(require mzlib/contract
"timer.ss")
(define-struct connection (id timer i-port o-port custodian close?)
#:mutable)
(provide/contract
[struct connection
([id integer?]
[timer timer?]
[i-port input-port?]
[o-port output-port?]
[custodian custodian?]
[close? boolean?])]
[start-connection-manager (custodian? . -> . void)]
[new-connection (number? input-port? output-port? custodian? boolean? . -> . connection?)]
[kill-connection! (connection? . -> . void)]
[adjust-connection-timeout! (connection? number? . -> . void)])
;; start-connection-manager: custodian -> void
;; calls the timer manager
(define (start-connection-manager custodian)
(start-timer-manager custodian))
;; new-connection: number i-port o-port custodian -> connection
;; ask the connection manager for a new connection
(define i (box 0))
(define (new-connection time-to-live i-port o-port cust close?)
(define conn
(make-connection
(begin0 (unbox i) (set-box! i (add1 (unbox i))))
#f i-port o-port cust close?))
(define conn-wb (make-weak-box conn))
(set-connection-timer!
conn
(start-timer time-to-live
(lambda ()
(cond
[(weak-box-value conn-wb)
=> kill-connection!]))))
conn)
;; kill-connection!: connection -> void
;; kill this connection
(define (kill-connection! conn)
#;(printf "K: ~a~n" (connection-id conn))
; XXX Don't need to do this when called from timer
(with-handlers ([exn? void])
(cancel-timer! (connection-timer conn)))
(with-handlers ([exn:fail:network? void])
(close-output-port (connection-o-port conn)))
(with-handlers ([exn:fail:network? void])
(close-input-port (connection-i-port conn)))
(custodian-shutdown-all (connection-custodian conn)))
;; adjust-connection-timeout!: connection number -> void
;; change the expiration time for this connection
(define (adjust-connection-timeout! conn time)
(reset-timer! (connection-timer conn) time))