add LOCALE:AVAILABLE and LOCALE:SELECTED-FOR

Signed-off-by: Sean Whitton <spwhitton@spwhitton.name>

1 files changed, 77 insertions, 0 deletions

diff --git a/src/property/locale.lisp b/src/property/locale.lisp
new file mode 100644
index 0000000..950deef
--- /dev/null
+++ b/src/property/locale.lisp
@@ -0,0 +1,77 @@
+;;; Consfigurator -- Lisp declarative configuration management system
+
+;;; Copyright (C) 2015, 2021  Sean Whitton <spwhitton@spwhitton.name>
+
+;;; This file 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, or (at your option)
+;;; any later version.
+
+;;; This file 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+
+(in-package :consfigurator.property.locale)
+(named-readtables:in-readtable :consfigurator)
+
+(defprop %available :posix (locale)
+  (:desc (declare (ignore locale)) "/etc/locale.gen updated")
+  (:apply
+   (assert-euid-root)
+   (file:map-file-lines
+    "/etc/locale.gen"
+    (lambda (lines)
+      (loop with found
+            for line in lines
+            for start = (re:scan #?/\Q${locale}\E\b/ line)
+            if start
+              collect (subseq line start) and do (setq found t)
+            else
+              collect line
+            finally (unless found
+                      (failed-change
+                       #?"${locale} not found in /etc/locale.gen")))))))
+
+(defproplist available :posix (locale)
+  "Ensure that the locale LOCALE is generated and available.
+
+Fails if a locale is not available to be generated.  That is, a commented out
+entry for the locale and an accompanying charset must be present in
+/etc/locale.gen.
+
+Per Debian bug #684134 we cannot ensure a locale is generated by means of
+APT:RECONFIGURE.  So this property edits /etc/locale.gen manually."
+  (apt:installed "locales")
+  (on-change (%available locale)
+    (cmd:single "locale-gen")))
+
+(defprop selected-for :posix (locale &rest locale-variables)
+  "Select a locale for a list of global locale variables.
+
+A locale variable is of the form LC_FOO, LANG or LANGUAGE.  See locale(5).
+One might say
+
+    (locale:selected-for \"en_GB.UTF-8\" \"LC_PAPER\" \"LC_MONETARY\")
+
+to select the British English locale for paper size and currency conventions.
+
+Note that reverting this property does not make a locale unavailable.  That's
+because it might be required for other applications of this property."
+  (:desc (format nil "~A locale selected for ~{~A~^ ~}"
+                 locale locale-variables))
+  (:hostattrs
+   (declare (ignore locale locale-variables))
+   (os:required 'os:debianlike))
+  (:apply
+   (ignoring-hostattrs (available locale))
+   (with-change-if-changes-file ("/etc/default/locale")
+     (run "update-locale"
+          (mapcar (lambda (v) (strcat v "=" locale)) locale-variables))))
+  (:unapply
+   (declare (ignore locale))
+   (with-change-if-changes-file ("/etc/default/locale")
+     (run "update-locale" locale-variables))))