home: services: Add home-unclutter-service-type.

* gnu/home/services/desktop.scm (home-unclutter-configuration)
(home-unclutter-service-type): New variables;
(home-unclutter-shepherd-service): New procedure;
* doc/guix.texi (Desktop Services): Document it.

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

doc/guix.texi

@@ -42541,6 +42541,36 @@ The package providing the @code{/bin/dbus-daemon} command.
 @end table
 @end deftp
 
+@defvar home-unclutter-service-type
+This is the service type for Unclutter, a program that runs on the
+background of an X11 session and detects when the X pointer hasn't moved
+for a specified idle timeout, after which it hides the cursor so that
+you can focus on the text underneath.  Its associated value must be a
+@code{home-unclutter-configuration} record, as shown below.
+
+A typical configuration, where we manually specify the idle timeout (in
+seconds), might look like this:
+
+@lisp
+(service home-unclutter-service-type
+         (home-unclutter-configuration
+          (idle-timeout 2)))
+@end lisp
+@end defvar
+
+@deftp {Data Type} home-unclutter-configuration
+The configuration record for @code{home-unclutter-service-type}.
+
+@table @asis
+@item @code{unclutter} (default: @code{unclutter}) (type: file-like)
+Unclutter package to use.
+
+@item @code{idle-timeout} (default: @code{5}) (type: integer)
+A timeout in seconds after which to hide cursor.
+@end table
+
+@end deftp
+
 @node Guix Home Services
 @subsection Guix Home Services
 

gnu/home/services/desktop.scm

@@ -1,6 +1,7 @@
 ;;; GNU Guix --- Functional package management for GNU
 ;;; Copyright © 2022 Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright © 2022 ( <paren@disroot.org>
+;;; Copyright © 2023 conses <contact@conses.eu>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -22,7 +23,7 @@
   #:use-module (gnu home services shepherd)
   #:use-module (gnu services configuration)
   #:autoload   (gnu packages glib)    (dbus)
-  #:autoload   (gnu packages xdisorg) (redshift)
+  #:autoload   (gnu packages xdisorg) (redshift unclutter)
   #:use-module (guix records)
   #:use-module (guix gexp)
   #:use-module (srfi srfi-1)
@@ -32,7 +33,10 @@
             home-redshift-service-type
 
             home-dbus-configuration
-            home-dbus-service-type))
+            home-dbus-service-type
+
+            home-unclutter-configuration
+            home-unclutter-service-type))
 
 
 ;;;
@@ -226,3 +230,48 @@ according to time of day.")))
    (default-value (home-dbus-configuration))
    (description
     "Run the session-specific D-Bus inter-process message bus.")))
+
+
+;;;
+;;; Unclutter.
+;;;
+
+(define-configuration/no-serialization home-unclutter-configuration
+  (unclutter
+   (file-like unclutter)
+   "The @code{unclutter} package to use.")
+  (idle-timeout
+   (integer 5)
+   "Timeout in seconds after which to hide the cursor."))
+
+(define (home-unclutter-shepherd-service config)
+  (list
+   (shepherd-service
+    (provision '(unclutter))
+    (requirement '())
+    (one-shot? #t)
+    (start #~(make-forkexec-constructor
+              (list
+               #$(file-append
+                  (home-unclutter-configuration-unclutter config)
+                  "/bin/unclutter")
+               "-idle"
+               (number->string
+                #$(home-unclutter-configuration-idle-timeout config)))
+              #:log-file (string-append
+                          (or (getenv "XDG_LOG_HOME")
+                              (format #f "~a/.local/var/log"
+                                      (getenv "HOME")))
+                          "/unclutter.log"))))))
+
+(define home-unclutter-service-type
+  (service-type
+   (name 'home-unclutter)
+   (extensions
+    (list
+     (service-extension home-shepherd-service-type
+                        home-unclutter-shepherd-service)))
+   (default-value (home-unclutter-configuration))
+   (description "Run the @code{unclutter} daemon, which, on systems using the
+Xorg graphical display server, automatically hides the cursor after a
+user-defined timeout has expired.")))