07/09: system: Add procedures to access user accounts and service names.

[Ludovic Courtès]

civodul pushed a commit to branch master
in repository guix.

commit b2fef041fcfbb63d7901c25647373aeda56b026e
Author: Ludovic Courtès <address@hidden>
Date:   Wed May 4 22:48:28 2016 +0200

    system: Add procedures to access user accounts and service names.
    
    * gnu/system.scm (operating-system-user-accounts)
    (operating-system-shepherd-service-names): New procedures.
---
 gnu/system.scm |   18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/gnu/system.scm b/gnu/system.scm
index 768ca9c..96ea153 100644
--- a/gnu/system.scm
+++ b/gnu/system.scm
@@ -82,6 +82,8 @@
             operating-system-file-systems
             operating-system-store-file-system
             operating-system-activation-script
+            operating-system-user-accounts
+            operating-system-shepherd-service-names
 
             operating-system-derivation
             operating-system-profile
@@ -578,6 +580,22 @@ hardware-related operations as necessary when booting a 
Linux container."
     ;; BOOT is the script as a monadic value.
     (service-parameters boot)))
 
+(define (operating-system-user-accounts os)
+  "Return the list of user accounts of OS."
+  (let* ((services (operating-system-services os))
+         (account  (fold-services services
+                                  #:target-type account-service-type)))
+    (filter user-account?
+            (service-parameters account))))
+
+(define (operating-system-shepherd-service-names os)
+  "Return the list of Shepherd service names for OS."
+  (append-map shepherd-service-provision
+              (service-parameters
+               (fold-services (operating-system-services os)
+                              #:target-type
+                              shepherd-root-service-type))))
+
 (define* (operating-system-derivation os #:key container?)
   "Return a derivation that builds OS."
   (let* ((services (operating-system-services os #:container? container?))