gnu: Add ntp

* gnu/packages/ntp.scm: New file.
* gnu-system.am (gnu/packages/ntp.scm): Add it.

gnu-system.am

@@ -182,6 +182,7 @@ GNU_SYSTEM_MODULES =				\
   gnu/packages/nettle.scm			\
   gnu/packages/node.scm				\
   gnu/packages/noweb.scm			\
+  gnu/packages/ntp.scm				\
   gnu/packages/nvi.scm				\
   gnu/packages/ocaml.scm			\
   gnu/packages/ocrad.scm			\

gnu/packages/ntp.scm

@@ -0,0 +1,49 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright 2014  John Darrington <jmd@gnu.org>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix 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 General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (gnu packages ntp)
+  #:use-module (gnu packages)
+  #:use-module (gnu packages which)
+  #:use-module (guix licenses)
+  #:use-module (guix packages)
+  #:use-module (guix download)
+  #:use-module (guix build-system gnu)
+  #:use-module (srfi srfi-1))
+
+(define-public ntp
+  (package
+   (name "ntp")
+   (version "4.2.6p5")
+   (source (origin
+	    (method url-fetch)
+	    (uri (string-append 
+                  "http://www.eecis.udel.edu/~ntp/ntp_spool/ntp4/ntp-"
+                  (string-join (take (string-split version #\.) 2) ".")
+                  "/ntp-" version ".tar.gz"))
+	    (sha256
+	     (base32
+	      "077r69a41hasl8zf5c44km7cqgfhrkaj6a4jnr75j7nkz5qq7ayn"))))
+   (native-inputs `(("which" ,which)))
+   (build-system gnu-build-system)
+   (synopsis "Real time clock synchonization system")
+   (description "NTP is a system designed to synchronize the clocks of
+computers over a network.")
+   (license (x11-style 
+             "http://www.eecis.udel.edu/~mills/ntp/html/copyright.html"
+             "A non-copyleft free licence from the University of Delaware"))
+   (home-page "http://www.ntp.org")))