gnu: Add Transmission.

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

gnu-system.am

@@ -40,6 +40,7 @@ GNU_SYSTEM_MODULES =				\
   gnu/packages/bash.scm				\
   gnu/packages/bdb.scm				\
   gnu/packages/bdw-gc.scm			\
+  gnu/packages/bittorrent.scm			\
   gnu/packages/bison.scm			\
   gnu/packages/boost.scm			\
   gnu/packages/bootstrap.scm			\

gnu/packages/bittorrent.scm

+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2014 Ludovic Courtès <ludo@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 bittorrent)
+  #:use-module (guix packages)
+  #:use-module (guix download)
+  #:use-module (guix build-system gnu)
+  #:use-module ((guix licenses)
+                #:renamer (symbol-prefix-proc 'l:))
+  #:use-module (gnu packages openssl)
+  #:use-module (gnu packages libevent)
+  #:use-module (gnu packages curl)
+  #:use-module (gnu packages pkg-config)
+  #:use-module (gnu packages file)
+  #:use-module (gnu packages linux)
+  #:use-module ((gnu packages compression)
+                #:select (zlib))
+  #:use-module (gnu packages glib)
+  #:use-module (gnu packages gtk))
+
+(define-public transmission
+  (package
+    (name "transmission")
+    (version "2.83")
+    (source (origin
+              (method url-fetch)
+              (uri (string-append
+                    "https://transmission.cachefly.net/transmission-"
+                    version ".tar.xz"))
+              (sha256
+               (base32
+                "0cqlgl6jmjw1caybz6nzh3l8z0jak1dxba01isv72zvy2r8b1qdh"))))
+    (build-system gnu-build-system)
+    (outputs '("out"                      ; library and command-line interface
+               "gui"))                    ; graphical user interface
+    (arguments
+     '(#:phases (alist-cons-after
+                 'install 'move-gui
+                 (lambda* (#:key outputs #:allow-other-keys)
+                   ;; Move the GUI to its own output, so that "out" doesn't
+                   ;; depend on GTK+.
+                   (let ((out (assoc-ref outputs "out"))
+                         (gui (assoc-ref outputs "gui")))
+                     (mkdir-p (string-append gui "/bin"))
+                     (rename-file (string-append out "/bin/transmission-gtk")
+                                  (string-append gui
+                                                 "/bin/transmission-gtk"))))
+                 %standard-phases)))
+    (inputs
+     `(("inotify-tools" ,inotify-tools)
+       ("libevent" ,libevent)
+       ("curl" ,curl)
+       ("openssl" ,openssl)
+       ("file" ,file)
+       ("zlib" ,zlib)
+       ("gtk+" ,gtk+)))
+    (native-inputs
+     `(("intltool" ,intltool)
+       ("pkg-config" ,pkg-config)))
+    (home-page "http://www.transmissionbt.com/")
+    (synopsis "Fast and easy BitTorrent client")
+    (description
+     "Transmission is a BitTorrent client that comes with graphical,
+textual, and Web user interfaces.  Transmission also has a daemon for
+unattended operationg.  It supports local peer discovery, full encryption,
+DHT, µTP, PEX and Magnet Links.")
+
+    ;; COPYING reads:
+    ;;
+    ;;     Transmission can be redistributed and/or modified under the terms of
+    ;; the GNU GPLv2 (http://www.gnu.org/licenses/license-list.html#GPLv2),
+    ;; the GNU GPLv3 (http://www.gnu.org/licenses/license-list.html#GNUGPLv3),
+    ;; or any future license endorsed by Mnemosyne LLC.
+    ;;
+    ;; A few files files carry an MIT/X11 license header.
+    (license l:gpl3+)))