services: dnsmasq: Add stats and reload shepherd actions.

* gnu/services/dns.scm (dnsmasq-service-reload-action): New function.
Implements SIGHUP handling for reloading configurations.
(dnsmasq-service-stats-action): New function. Implements SIGUSR1
handling for dumping statistics.
(dnsmasq-shepherd-service): Use new actions.
* doc/guix.texi: Document new actions with examples.
* gnu/tests/networking.scm (%test-dnsmasq): Add tests to verify the
functionality of new actions.

Change-Id: I31f0eb4b26a582e95f7bfdb240110c139f0e16cc
Signed-off-by: Maxim Cournoyer <maxim.cournoyer@gmail.com>
Modified-by: Maxim Cournoyer <maxim.cournoyer@gmail.com>

1 files changed, 22 insertions, 0 deletions

diff --git a/gnu/services/dns.scm b/gnu/services/dns.scm
index d55ee3e4fcb..9a9b78d877b 100644
--- a/gnu/services/dns.scm
+++ b/gnu/services/dns.scm
@@ -874,6 +874,8 @@ cache.size = 100 * MB
      (provision (or provision shepherd-provision))
      (requirement shepherd-requirement)
      (documentation "Run the dnsmasq DNS server.")
+     (actions (list (dnsmasq-service-reload-action config)
+                    (dnsmasq-service-stats-action config)))
      (start #~(make-forkexec-constructor
                (list
                 #$(file-append package "/sbin/dnsmasq")
@@ -965,6 +967,26 @@ cache.size = 100 * MB
       ;; create directory to store dnsmasq lease file
       (mkdir-p "/var/lib/misc")))
 
+(define (dnsmasq-service-reload-action config)
+  (match-record config <dnsmasq-configuration> ()
+    (shepherd-action
+     (name 'reload)
+     (documentation "Send a @code{SIGHUP} signal to @command{dnsmasq} to clear
+cache and reload hosts files.")
+     (procedure #~(lambda (running)
+                    (let ((pid (process-id running)))
+                      (kill pid SIGHUP)))))))
+
+(define (dnsmasq-service-stats-action config)
+  (match-record config <dnsmasq-configuration> ()
+    (shepherd-action
+     (name 'stats)
+     (documentation "Send a @code{SIGUSR1} to write statistics to the system
+log.")
+     (procedure #~(lambda (running)
+                    (let ((pid (process-id running)))
+                      (kill pid SIGUSR1)))))))
+
 (define dnsmasq-service-type
   (service-type
    (name 'dnsmasq)