services: Add spice vdagent service.

* gnu/services/spice.scm: New file.
* gnu/local.mk (GNU_SYSTEM_MODULES): Add it.
* doc/guix.texi (Various Services): New subheading.

doc/guix.texi

@@ -9921,6 +9921,17 @@ Finally, @var{extra-options} is a list of additional command-line options
 passed to @command{lircd}.
 @end deffn
 
+@cindex spice
+@subsubheading Spice Service
+
+The @code{(gnu services spice)} module provides the following service.
+
+@deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
+Returns a service that runs @url{http://www.spice-space.org,VDAGENT}, a daemon
+that enables sharing the clipboard with a vm and setting the guest display
+resolution when the graphical console window resizes.
+@end deffn
+
 @subsubsection Dictionary Services
 The @code{(gnu services dict)} module provides the following service:
 

gnu/local.mk

@@ -383,6 +383,7 @@ GNU_SYSTEM_MODULES =				\
   %D%/services/networking.scm			\
   %D%/services/shepherd.scm			\
   %D%/services/herd.scm				\
+  %D%/services/spice.scm				\
   %D%/services/ssh.scm				\
   %D%/services/web.scm				\
   %D%/services/xorg.scm				\

gnu/services/spice.scm

@@ -0,0 +1,75 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2016 David Craven <david@craven.ch>
+;;;
+;;; 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 spice)
+  #:use-module (gnu packages spice)
+  #:use-module (gnu services)
+  #:use-module (gnu services shepherd)
+  #:use-module (guix gexp)
+  #:use-module (guix records)
+  #:export (spice-vdagent-configuration
+            spice-vdagent-configuration?
+            spice-vdagent-service-type
+            spice-vdagent-service))
+
+(define-record-type* <spice-vdagent-configuration>
+  spice-vdagent-configuration make-spice-vdagent-configuration
+  spice-vdagent-configuration?
+  (spice-vdagent spice-vdagent-configuration-spice-vdagent
+                 (default spice-vdagent)))
+
+(define (spice-vdagent-activation config)
+  "Return the activation gexp for CONFIG."
+  #~(mkdir-p "/var/run/spice-vdagentd"))
+
+(define (spice-vdagent-shepherd-service config)
+  "Return a <shepherd-service> for spice-vdagentd with CONFIG."
+  (define spice-vdagent (spice-vdagent-configuration-spice-vdagent config))
+
+  (define spice-vdagentd-command
+    (list
+      #~(string-append #$spice-vdagent "/sbin/spice-vdagentd")
+      "-x"))
+
+  (list
+    (shepherd-service
+      (documentation "Spice vdagentd service")
+      (requirement '(udev))
+      (provision '(spice-vdagentd))
+      (start #~(make-forkexec-constructor #$@spice-vdagentd-command))
+      (stop #~(make-kill-destructor)))))
+
+(define spice-vdagent-profile
+  (compose list spice-vdagent-configuration-spice-vdagent))
+
+(define spice-vdagent-service-type
+  (service-type (name 'spice-vdagent)
+    (extensions
+      (list (service-extension shepherd-root-service-type
+                               spice-vdagent-shepherd-service)
+            (service-extension activation-service-type
+                               spice-vdagent-activation)
+            (service-extension profile-service-type
+                               spice-vdagent-profile)))))
+
+(define* (spice-vdagent-service
+          #:optional (config (spice-vdagent-configuration)))
+  "Start the @command{vdagentd} and @command{vdagent} deamons
+from @var{spice-vdagent} to enable guest window resizing and
+clipboard sharing."
+  (service spice-vdagent-service-type config))