gnu: Introduce the (gnu services ...) modules.

* gnu/system/dmd.scm: Remove file.  Move contents to...
* gnu/services.scm, gnu/services/base.scm, gnu/services/dmd.scm,
  gnu/services/networking.scm, gnu/services/xorg.scm: ... here.  New
  files.
* gnu/system.scm, gnu/system/vm.scm: Adjust accordingly.
* guix/scripts/system.scm (%user-module): Likewise.
* doc/guix.texi (Using the Configuration System): Likewise.
  (Defining Services): Likewise.

1 files changed, 77 insertions, 0 deletions

diff --git a/gnu/services/dmd.scm b/gnu/services/dmd.scm
new file mode 100644
index 0000000000..21719118eb
--- /dev/null
+++ b/gnu/services/dmd.scm
@@ -0,0 +1,77 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2013, 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 services dmd)
+  #:use-module (guix monads)
+  #:use-module (gnu services)
+  #:use-module (ice-9 match)
+  #:use-module (srfi srfi-1)
+  #:export (dmd-configuration-file))
+
+;;; Commentary:
+;;;
+;;; Instantiating system services as a dmd configuration file.
+;;;
+;;; Code:
+
+(define (dmd-configuration-file services etc)
+  "Return the dmd configuration file for SERVICES, that initializes /etc from
+ETC (the name of a directory in the store) on startup."
+  (define config
+    `(begin
+       (use-modules (ice-9 ftw))
+
+       (register-services
+        ,@(map (lambda (service)
+                `(make <service>
+                   #:docstring ',(service-documentation service)
+                   #:provides ',(service-provision service)
+                   #:requires ',(service-requirement service)
+                   #:respawn? ',(service-respawn? service)
+                   #:start ,(service-start service)
+                   #:stop ,(service-stop service)))
+               services))
+
+       ;; /etc is a mixture of static and dynamic settings.  Here is where we
+       ;; initialize it from the static part.
+       (format #t "populating /etc from ~a...~%" ,etc)
+       (let ((rm-f (lambda (f)
+                     (false-if-exception (delete-file f)))))
+         (rm-f "/etc/static")
+         (symlink ,etc "/etc/static")
+         (for-each (lambda (file)
+                     ;; TODO: Handle 'shadow' specially so that changed
+                     ;; password aren't lost.
+                     (let ((target (string-append "/etc/" file))
+                           (source (string-append "/etc/static/" file)))
+                       (rm-f target)
+                       (symlink source target)))
+                   (scandir ,etc
+                            (lambda (file)
+                              (not (member file '("." ".."))))))
+
+         ;; Prevent ETC from being GC'd.
+         (rm-f "/var/nix/gcroots/etc-directory")
+         (symlink ,etc "/var/nix/gcroots/etc-directory"))
+
+       (format #t "starting services...~%")
+       (for-each start ',(append-map service-provision services))))
+
+  (text-file "dmd.conf" (object->string config)))
+
+;;; dmd.scm ends here