utils: Add 'get-user'

* src/mcron/utils.scm (get-user): New procedure.
* src/mcron/job-specifier.scm (job): Use it.
* src/mcron/base.scm (remove-user-jobs): Likewise.

src/mcron/base.scm

@@ -28,6 +28,7 @@
 (define-module (mcron base)
   #:use-module (ice-9 match)
   #:use-module (mcron environment)
+  #:use-module (mcron utils)
   #:use-module (srfi srfi-1)
   #:use-module (srfi srfi-2)
   #:use-module (srfi srfi-9)
@@ -85,9 +86,7 @@ This procedure is deprecated."
 (define* (remove-user-jobs user #:key (schedule %global-schedule))
   "Remove user jobs from SCHEDULE belonging to USER.  USER must be either a
 username, a UID, or a passwd entry."
-  (let ((user* (if (or (string? user) (integer? user))
-                   (getpw user)
-                   user)))
+  (let ((user* (get-user user)))
     (set-schedule-user! schedule
                         (filter (lambda (job)
                                   (not (eqv? (passwd:uid user*)

src/mcron/job-specifier.scm

@@ -1,6 +1,6 @@
 ;;;; job-specifier.scm -- public interface for defining jobs
 ;;; Copyright © 2003 Dale Mellor <dale_mellor@users.sourceforge.net>
-;;; Copyright © 2016, 2017 Mathieu Lirzin <mthl@gnu.org>
+;;; Copyright © 2016, 2017, 2018 Mathieu Lirzin <mthl@gnu.org>
 ;;;
 ;;; This file is part of GNU Mcron.
 ;;;
@@ -30,6 +30,7 @@
   #:use-module (ice-9 match)
   #:use-module (mcron base)
   #:use-module (mcron environment)
+  #:use-module (mcron utils)
   #:use-module (mcron vixie-time)
   #:use-module (srfi srfi-1)
   #:re-export (append-environment-mods)
@@ -241,9 +242,7 @@ go into the list.  For example, (range 1 6 2) returns '(1 3 5)."
                ((procedure? action) "Lambda function")
                ((string? action)    action)
                ((list? action)      (simple-format #f "~A" action))))
-        (user* (if (or (string? user) (integer? user))
-                   (getpw user)
-                   user)))
+        (user* (get-user user)))
     (add-job (lambda (current-time)
                (parameterize ((%current-action-time current-time))
                  ;; Allow for daylight savings time changes.

src/mcron/utils.scm

@@ -29,7 +29,8 @@
             parse-args
             show-version
             show-package-information
-            process-update-request)
+            process-update-request
+            get-user)
   #:re-export (option-ref
                read-string))
 
@@ -101,3 +102,13 @@ comes in on the above socket."
            (remove-user-jobs user)
            (set-configuration-user user)
            (read-vixie-file (string-append config-spool-dir "/" user-name)))))))
+
+(define (get-user spec)
+  "Return the passwd entry corresponding to SPEC.  If SPEC is passwd entry
+then return it.  If SPEC is not a valid specification throw an exception."
+  (cond ((or (string? spec) (integer? spec))
+         (getpw spec))
+        ((vector? spec)                 ;assume a user passwd entry
+         spec)
+        (else
+         (throw 'invalid-user-specification spec))))