gnu: Add LibreCAD.

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

gnu-system.am

@@ -91,6 +91,7 @@ GNU_SYSTEM_MODULES =				\
   gnu/packages/elf.scm				\
   gnu/packages/emacs.scm			\
   gnu/packages/enchant.scm			\
+  gnu/packages/engineering.scm			\
   gnu/packages/enlightenment.scm		\
   gnu/packages/feh.scm                          \
   gnu/packages/file.scm				\

gnu/packages/engineering.scm

@@ -0,0 +1,85 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2015 Ricardo Wurmus <rekado@elephly.net>
+;;;
+;;; 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 audio)
+  #:use-module (guix packages)
+  #:use-module (guix download)
+  #:use-module (guix git-download)
+  #:use-module ((guix licenses) #:prefix license:)
+  #:use-module (guix build-system gnu)
+  #:use-module (gnu packages)
+  #:use-module (gnu packages boost)
+  #:use-module (gnu packages fontutils)
+  #:use-module (gnu packages maths)
+  #:use-module (gnu packages pkg-config)
+  #:use-module (gnu packages qt)
+  #:use-module (srfi srfi-1))
+
+(define-public librecad
+  (package
+    (name "librecad")
+    (version "2.0.6-rc")
+    (source (origin
+              (method url-fetch)
+              (uri (string-append
+                    "https://github.com/LibreCAD/LibreCAD/archive/"
+                    version ".tar.gz"))
+              (file-name (string-append name "-" version))
+              (sha256
+               (base32
+                "1n1mh8asj6yrl5hi438dvizmrbqk1kni5xkizhi3pdmkg7z3hksm"))))
+    (build-system gnu-build-system)
+    (arguments
+     '(#:phases
+       (alist-cons-after
+        'unpack
+        'patch-paths
+        (lambda* (#:key outputs #:allow-other-keys)
+          (let ((out (assoc-ref outputs "out")))
+            (substitute* "librecad/src/lib/engine/rs_system.cpp"
+              (("/usr/share") (string-append out "/share")))))
+        (alist-replace
+         'configure
+         (lambda* (#:key inputs #:allow-other-keys)
+           (system* "qmake" (string-append "BOOST_DIR="
+                                           (assoc-ref inputs "boost"))))
+         (alist-replace
+          'install
+          (lambda* (#:key outputs #:allow-other-keys)
+            (let ((out (assoc-ref outputs "out")))
+              (mkdir-p (string-append out "/bin"))
+              (mkdir-p (string-append out "/share/librecad"))
+              (copy-file "unix/librecad"
+                         (string-append out "/bin/librecad"))
+              (copy-recursively "unix/resources"
+                                (string-append out "/share/librecad"))))
+          %standard-phases)))))
+    (inputs
+     `(("boost" ,boost)
+       ("muparser" ,muparser)
+       ("freetype" ,freetype)
+       ("qt" ,qt-4)))
+    (native-inputs
+     `(("pkg-config" ,pkg-config)
+       ("which" ,which)))
+    (home-page "http://librecad.org/")
+    (synopsis "Computer-aided design (CAD) application")
+    (description
+     "LibreCAD is a 2D Computer-aided design (CAD) application for creating
+plans and designs.")
+    (license license:gpl2)))