X-Git-Url: https://git.hcoop.net/jackhill/guix/guix.git/blobdiff_plain/072e10615fc786db02dc44f3cd5f25aed2969111..49b6dc2b4e02269850dacc71d9e7ec93139ec5b5:/gnu/services/herd.scm

diff --git a/gnu/services/herd.scm b/gnu/services/herd.scm
index 03bfbf1d78..8c96b70731 100644
--- a/gnu/services/herd.scm
+++ b/gnu/services/herd.scm
@@ -1,5 +1,6 @@
 ;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2016 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2016, 2017, 2018 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2017 Mathieu Othacehe <m.othacehe@gmail.com>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -23,7 +24,9 @@
   #:use-module (srfi srfi-34)
   #:use-module (srfi srfi-35)
   #:use-module (ice-9 match)
-  #:export (shepherd-error?
+  #:export (%shepherd-socket-file
+
+            shepherd-error?
             service-not-found-error?
             service-not-found-error-service
             action-not-found-error?
@@ -42,11 +45,13 @@
             live-service-requirement
             live-service-running
 
+            with-shepherd-action
             current-services
             unload-services
             unload-service
             load-services
-            start-service))
+            start-service
+            stop-service))
 
 ;;; Commentary:
 ;;;
@@ -58,9 +63,9 @@
 ;;; Code:
 
 (define %shepherd-socket-file
-  "/var/run/shepherd/socket")
+  (make-parameter "/var/run/shepherd/socket"))
 
-(define* (open-connection #:optional (file %shepherd-socket-file))
+(define* (open-connection #:optional (file (%shepherd-socket-file)))
   "Open a connection to the daemon, using the Unix-domain socket at FILE, and
 return the socket."
   ;; The protocol is sexp-based and UTF-8-encoded.
@@ -79,7 +84,12 @@ return the socket."
 (define-syntax-rule (with-shepherd connection body ...)
   "Evaluate BODY... with CONNECTION bound to an open socket to PID 1."
   (let ((connection (open-connection)))
-    body ...))
+    (dynamic-wind
+      (const #t)
+      (lambda ()
+        body ...)
+      (lambda ()
+        (close-port connection)))))
 
 (define-condition-type &shepherd-error &error
   shepherd-error?)
@@ -132,7 +142,8 @@ does not denote an error."
 
 (define* (invoke-action service action arguments cont)
   "Invoke ACTION on SERVICE with ARGUMENTS.  On success, call CONT with the
-result.  Otherwise return #f."
+list of results (one result per instance with the name SERVICE).  Otherwise
+return #f."
   (with-shepherd sock
     (write `(shepherd-command (version 0)
                               (action ,action)
@@ -143,7 +154,7 @@ result.  Otherwise return #f."
     (force-output sock)
 
     (match (read sock)
-      (('reply ('version 0 _ ...) ('result (result)) ('error #f)
+      (('reply ('version 0 _ ...) ('result result) ('error #f)
                ('messages messages))
        (for-each display-message messages)
        (cont result))
@@ -158,6 +169,8 @@ result.  Otherwise return #f."
 
 (define-syntax-rule (with-shepherd-action service (action args ...)
                       result body ...)
+  "Invoke ACTION on SERVICE with the given ARGS, and evaluate BODY with RESULT
+bound to the action's result."
   (invoke-action service action (list args ...)
                  (lambda (result) body ...)))
 
@@ -182,30 +195,34 @@ of pairs."
   "Return the list of currently defined Shepherd services, represented as
 <live-service> objects.  Return #f if the list of services could not be
 obtained."
-  (with-shepherd-action 'root ('status) services
-    (match services
-      ((('service ('version 0 _ ...) _ ...) ...)
-       (map (lambda (service)
-              (alist-let* service (provides requires running)
-                (live-service provides requires running)))
-            services))
-      (x
-       #f))))
+  (with-shepherd-action 'root ('status) results
+    ;; We get a list of results, one for each service with the name 'root'.
+    ;; In practice there's only one such service though.
+    (match results
+      ((services _ ...)
+       (match services
+         ((('service ('version 0 _ ...) _ ...) ...)
+          (map (lambda (service)
+                 (alist-let* service (provides requires running)
+                   (live-service provides requires running)))
+               services))
+         (x
+          #f))))))
 
 (define (unload-service service)
   "Unload SERVICE, a symbol name; return #t on success."
   (with-shepherd-action 'root ('unload (symbol->string service)) result
-    result))
+    (first result)))
 
 (define (%load-file file)
   "Load FILE in the Shepherd."
   (with-shepherd-action 'root ('load file) result
-    result))
+    (first result)))
 
 (define (eval-there exp)
   "Eval EXP in the Shepherd."
   (with-shepherd-action 'root ('eval (object->string exp)) result
-    result))
+    (first result)))
 
 (define (load-services files)
   "Load and register the services from FILES, where FILES contain code that
@@ -219,6 +236,10 @@ returns a shepherd <service> object."
   (with-shepherd-action name ('start) result
     result))
 
+(define (stop-service name)
+  (with-shepherd-action name ('stop) result
+    result))
+
 ;; Local Variables:
 ;; eval: (put 'alist-let* 'scheme-indent-function 2)
 ;; eval: (put 'with-shepherd 'scheme-indent-function 1)