guix: Add the 'qt' build system.

* guix/build-system/qt.scm, guix/build/qt-build-system.scm: New files.
* Makefile.am (MODULES): Add them.
* doc/guix.texi (Buiild systems): Add the new build system.

1 files changed, 109 insertions, 0 deletions

diff --git a/guix/build/qt-build-system.scm b/guix/build/qt-build-system.scm
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+++ b/guix/build/qt-build-system.scm
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+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2014 Federico Beffa <beffa@fbengineering.ch>
+;;; Copyright © 2014, 2015 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2018 Mark H Weaver <mhw@netris.org>
+;;; Copyright © 2019 Hartmut Goebel <h.goebel@crazy-compilers.com>
+;;;
+;;; 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 (guix build qt-build-system)
+  #:use-module ((guix build cmake-build-system) #:prefix cmake:)
+  #:use-module (guix build utils)
+  #:use-module (ice-9 match)
+  #:use-module (ice-9 regex)
+  #:use-module (ice-9 ftw)
+  #:use-module (srfi srfi-1)
+  #:use-module (srfi srfi-26)
+  #:export (%standard-phases
+            qt-build))
+
+;; Commentary:
+;;
+;; Builder-side code of the standard Qt build procedure.
+;;
+;; Code:
+
+(define (variables-for-wrapping base-directories)
+
+  (define (collect-sub-dirs base-directories subdirectory)
+    (filter-map
+     (lambda (dir)
+       (let ((directory (string-append dir subdirectory)))
+         (if (directory-exists? directory) directory #f)))
+     base-directories))
+
+  (filter
+   (lambda (var-to-wrap) (not (null? (last var-to-wrap))))
+   (map
+    (lambda (var-spec)
+      `(,(first var-spec) = ,(collect-sub-dirs base-directories (last var-spec))))
+    (list
+     ;; these shall match the search-path-specification for Qt and KDE
+     ;; libraries
+     '("XDG_DATA_DIRS" "/share")
+     '("XDG_CONFIG_DIRS" "/etc/xdg")
+     '("QT_PLUGIN_PATH" "/lib/qt5/plugins")
+     '("QML2_IMPORT_PATH" "/lib/qt5/qml")))))
+
+(define* (wrap-all-programs #:key inputs outputs
+                            (qt-wrap-excluded-outputs '())
+                            #:allow-other-keys)
+  "Implement phase \"qt-wrap\": look for GSettings schemas and
+gtk+-v.0 libraries and create wrappers with suitably set environment variables
+if found.
+
+Wrapping is not applied to outputs whose name is listed in
+QT-WRAP-EXCLUDED-OUTPUTS.  This is useful when an output is known not
+to contain any Qt binaries, and where wrapping would gratuitously
+add a dependency of that output on Qt."
+  (define (find-files-to-wrap directory)
+    (append-map
+     (lambda (dir)
+       (if (directory-exists? dir) (find-files dir ".*") (list)))
+     (list (string-append directory "/bin")
+           (string-append directory "/sbin")
+           (string-append directory "/libexec")
+           (string-append directory "/lib/libexec"))))
+
+  (define input-directories
+    ;; FIXME: Filter out unwanted inputs, e.g. cmake
+    (match inputs
+           (((_ . dir) ...)
+            dir)))
+
+  (define handle-output
+    (match-lambda
+     ((output . directory)
+      (unless (member output qt-wrap-excluded-outputs)
+        (let ((bin-list     (find-files-to-wrap directory))
+              (vars-to-wrap (variables-for-wrapping
+                             (append (list output)
+                                         input-directories))))
+          (when (not (null? vars-to-wrap))
+            (for-each (cut apply wrap-program <> vars-to-wrap)
+                      bin-list)))))))
+
+  (for-each handle-output outputs)
+  #t)
+
+(define %standard-phases
+  (modify-phases cmake:%standard-phases
+    (add-after 'install 'qt-wrap wrap-all-programs)))
+
+(define* (qt-build #:key inputs (phases %standard-phases)
+                   #:allow-other-keys #:rest args)
+  "Build the given package, applying all of PHASES in order."
+  (apply cmake:cmake-build #:inputs inputs #:phases phases args))