mdw@git.distorted.org.uk Git - zone/blob - sys.lisp

   1 ;;; -*-lisp-*-
   2 ;;;
   3 ;;; System-specific functions
   4 ;;;
   5 ;;; (c) 2008 Straylight/Edgeware
   6 ;;;
   7
   8 ;;;----- Licensing notice ---------------------------------------------------
   9 ;;;
  10 ;;; This program is free software; you can redistribute it and/or modify
  11 ;;; it under the terms of the GNU General Public License as published by
  12 ;;; the Free Software Foundation; either version 2 of the License, or
  13 ;;; (at your option) any later version.
  14 ;;;
  15 ;;; This program is distributed in the hope that it will be useful,
  16 ;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ;;; GNU General Public License for more details.
  19 ;;;
  20 ;;; You should have received a copy of the GNU General Public License
  21 ;;; along with this program; if not, write to the Free Software Foundation,
  22 ;;; Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23
  24 (cl:defpackage #:net-sys
  25   (:use #:common-lisp)
  26   (:export #:gethostname #:resolve-hostname #:canonify-hostname))
  27 (cl:in-package #:net-sys)
  28
  29 ;;;--------------------------------------------------------------------------
  30 ;;; Functions provided.
  31
  32 #+ecl
  33 (cffi:defcfun gethostname :int
  34   (name :pointer)
  35   (len :uint))
  36
  37 (defun gethostname ()
  38   "Return the hostname (not necessarily canonical) of the current host."
  39
  40   #+cmu
  41   (unix:unix-gethostname)
  42
  43   #+sbcl
  44   (sb-unix:unix-gethostname)
  45
  46   #+clisp
  47   (unix:get-host-name)
  48
  49   #+ecl
  50   (cffi:with-foreign-pointer-as-string (buffer 256 len)
  51     (let ((rc (gethostname buffer len)))
  52       (unless (zerop rc)
  53         (error "gethostname(2) failed (rc = ~A)." rc))))
  54
  55   #-(or cmu sbcl clisp ecl)
  56   "<unknown-host>")
  57
  58 (defun resolve-hostname (name)
  59   "Resolve a hostname to an IP address using the DNS, or return nil."
  60
  61   #+cmu
  62   (let ((he (ext:lookup-host-entry name)))
  63     (and he (ext:host-entry-addr he)))
  64
  65   #+sbcl
  66   (handler-case
  67       (let* ((he (sb-bsd-sockets:get-host-by-name name))
  68              (addr (sb-bsd-sockets:host-ent-address he)))
  69         (reduce (lambda (acc byte) (logior (ash acc 8) byte)) addr))
  70     (sb-bsd-sockets:name-service-error () nil))
  71
  72   #+clisp
  73   (let ((he (ext:resolve-host-ipaddr name)))
  74     (and he (string-ipaddr (car (ext:hostent-addr-list he)))))
  75
  76   #+ecl
  77   (nth-value 2 (ext:lookup-host-entry name))
  78
  79   #-(or cmu sbcl clisp ecl)
  80   nil)
  81
  82 (defun canonify-hostname (name)
  83   "Resolve a hostname to canonical form using the DNS, or return nil."
  84
  85   #+cmu
  86   (let ((he (ext:lookup-host-entry name)))
  87     (and he (ext:host-entry-name he)))
  88
  89   #+sbcl
  90   (handler-case
  91       (let ((he (sb-bsd-sockets:get-host-by-name name)))
  92         (sb-bsd-sockets:host-ent-name he))
  93     (sb-bsd-sockets:name-service-error () nil))
  94
  95   #+clisp
  96   (let ((he (ext:resolve-host-ipaddr name)))
  97     (and he (ext:hostent-name he)))
  98
  99   #+ecl
 100   (nth-value 0 (ext:lookup-host-entry name))
 101
 102   #-(or cmu sbcl clisp ecl)
 103   name)
 104
 105 ;;;----- That's all, folks --------------------------------------------------