gnu: Add libportal.

* gnu/packages/freedesktop.scm (libportal): New variable.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

gnu/packages/freedesktop.scm

@@ -20,6 +20,7 @@
 ;;; Copyright © 2020 Jakub Kądziołka <kuba@kadziolka.net>
 ;;; Copyright © 2020 Rene Saavedra <pacoon@protonmail.com>
 ;;; Copyright © 2020 Nicolò Balzarotti <nicolo@nixo.xyz>
+;;; Copyright © 2020 Anders Thuné <asse.97@gmail.com>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -1881,3 +1882,47 @@ (define-public libappindicator
 into the Unity menu bar.  Based on KSNI, it also works in KDE and will
 fallback to generic Systray support if none of those are available.")
     (license license:lgpl2.1+)))
+
+(define-public libportal
+  (let ((commit "bff3289")
+        (revision "1"))
+    (package
+      (name "libportal")
+      (version (git-version "0.3" revision commit))
+      (source (origin
+                (method git-fetch)
+                (uri (git-reference
+                      (url "https://github.com/flatpak/libportal")
+                      (commit commit)))
+                (file-name (git-file-name name version))
+                (sha256
+                 (base32
+                  "104b91qircr1i9jkmm6f725awywky52aimrki303kiaadn2v8b5i"))))
+      (build-system meson-build-system)
+      (arguments
+       `(#:phases
+         (modify-phases %standard-phases
+           (add-after 'install 'move-doc
+             (lambda* (#:key outputs #:allow-other-keys)
+               (let ((out (assoc-ref outputs "out"))
+                     (doc (assoc-ref outputs "doc"))
+                     (html "/share/gtk-doc"))
+                 (copy-recursively (string-append out html)
+                                   (string-append doc html))
+                 (delete-file-recursively (string-append out html))
+                 #t))))))
+      (native-inputs
+       `(("pkg-config" ,pkg-config)
+         ("gtk-doc" ,gtk-doc)
+         ("docbook-xsl" ,docbook-xsl)
+         ("docbook-xml" ,docbook-xml)
+         ("libxml2" ,libxml2)
+         ("glib:bin" ,glib "bin")))
+      (propagated-inputs
+       `(("glib" ,glib)))
+      (outputs '("out" "doc"))
+      (home-page "https://github.com/flatpak/libportal")
+      (synopsis "Flatpak portal library")
+      (description
+       "libportal provides GIO-style async APIs for most Flatpak portals.")
+      (license license:lgpl2.1+))))