services: xorg: Add sawfish session.

* gnu/services/xorg.scm (%sawfish-session-type): New variable.
* doc/guix.texi (X Window): Mention it.

doc/guix.texi

@@ -4579,6 +4579,10 @@ Session type using the Ratpoison window manager.
 Session type using the WindowMaker window manager.
 @end defvr
 
+@defvr {Scheme Variable} %sawfish-session-type
+Session type using the Sawfish window manager.
+@end defvr
+
 @defvr {Scheme Variable} %default-theme
 @defvrx {Scheme Variable} %default-theme-name
 The G-Expression denoting the default SLiM theme and its name.

gnu/services/xorg.scm

@@ -27,6 +27,7 @@
   #:use-module (gnu packages slim)
   #:use-module (gnu packages ratpoison)
   #:use-module (gnu packages gnustep)
+  #:use-module (gnu packages sawfish)
   #:use-module (gnu packages admin)
   #:use-module (gnu packages bash)
   #:use-module (guix gexp)
@@ -41,6 +42,7 @@
             %default-xsessions
             %ratpoison-session-type
             %windowmaker-session-type
+            %sawfish-session-type
 
             session-type?
             session-type-name
@@ -194,6 +196,11 @@ which should be passed to this script as the first argument.  If not, the
    (name "Ratpoison")
    (executable #~(string-append #$ratpoison "/bin/ratpoison"))))
 
+(define %sawfish-session-type
+  (session-type
+   (name "Sawfish")
+   (executable #~(string-append #$sawfish "/bin/sawfish"))))
+
 (define %default-xsessions
   ;; Default session types available to the log-in manager.
   (list %windowmaker-session-type %ratpoison-session-type))