70 lines
2.1 KiB
Scheme
70 lines
2.1 KiB
Scheme
; some useful utilities
|
|
|
|
;;; This file is part of the Scheme Untergrund Networking package.
|
|
|
|
;;; Copyright (c) 2002 by Andreas Bernauer.
|
|
;;; For copyright information, see the file COPYING which comes with
|
|
;;; the distribution.
|
|
|
|
(define (host-name-or-ip addr)
|
|
(with-fatal-error-handler
|
|
(lambda (condition more)
|
|
(call-with-values
|
|
(lambda () (socket-address->internet-address addr))
|
|
(lambda (ip port)
|
|
(format-internet-host-address ip))))
|
|
(host-info:name (host-info addr))))
|
|
|
|
(define (on-interrupt interrupt thunk)
|
|
(let lp ((event (most-recent-sigevent)))
|
|
(let ((next (next-sigevent event interrupt)))
|
|
(thunk)
|
|
(lp next))))
|
|
|
|
(define (socket-address->string socket-address . with-port?)
|
|
(let ((with-port? (:optional with-port? #t)))
|
|
(receive (host-address service-port)
|
|
(socket-address->internet-address socket-address)
|
|
(if with-port?
|
|
(format #f "~A:~A"
|
|
(format-internet-host-address host-address)
|
|
(format-port service-port))
|
|
(format #f "~A"
|
|
(format-internet-host-address host-address))))))
|
|
|
|
|
|
;;; Assemble a filename from ROOT and the elts of PATH-LIST.
|
|
;;; If the assembled filename contains a .. subdirectory, return #f,
|
|
;;; otw return the filename.
|
|
|
|
(define dotdot-check
|
|
(let ((dotdot-re (make-regexp "(^|/)\\.\\.($|/)"))) ; Matches a .. subdir.
|
|
(lambda (root path-list)
|
|
(let ((fname (if (null? path-list) root ; Bogus hack.
|
|
(string-append (file-name-as-directory root)
|
|
(string-join path-list "/")))))
|
|
(and (not (regexp-exec dotdot-re fname)) ; Check for .. subdir.
|
|
fname)))))
|
|
|
|
;;; Timeout on network writes?
|
|
|
|
(define (copy-inport->outport in out . maybe-buffer-size)
|
|
(let* ((buffer-size (:optional maybe-buffer-size 1024))
|
|
(buf (make-string buffer-size)))
|
|
(let loop ()
|
|
(cond ((read-string! buf in) => (lambda (nchars)
|
|
(write-string buf out 0 nchars)
|
|
(loop)))))
|
|
(force-output out)))
|
|
|
|
(define (dump fd)
|
|
(copy-inport->outport fd (current-output-port)))
|
|
|
|
(define (with-lock lock thunk)
|
|
(dynamic-wind
|
|
(lambda ()
|
|
(release-lock lock))
|
|
thunk
|
|
(lambda ()
|
|
(release-lock lock))))
|