[shepherd] 01/01: shepherd: Ignore reboot(2) errors in containers.

[Ludovic Courtès]

civodul pushed a commit to branch master
in repository shepherd.

commit 92e806bac1abaeeaf5d60f0ab50d1ae85ba6a62f
Author: Ludovic Courtès <address@hidden>
Date:   Wed Sep 26 22:27:40 2018 +0200

    shepherd: Ignore reboot(2) errors in containers.
    
    * modules/shepherd.scm (main): Ignore EINVAL and EPERM raised by
    'disable-reboot-on-ctrl-alt-del'.
---
 modules/shepherd.scm | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/modules/shepherd.scm b/modules/shepherd.scm
index 628267b..e241e7a 100644
--- a/modules/shepherd.scm
+++ b/modules/shepherd.scm
@@ -219,7 +219,16 @@
         ;; When running as PID 1, disable hard reboots upon ctrl-alt-del.
         ;; Instead, the kernel will send us SIGINT so that we can gracefully
         ;; shut down.  See ctrlaltdel(8) and kernel/reboot.c.
-        (disable-reboot-on-ctrl-alt-del))
+        (catch 'system-error
+          (lambda ()
+            (disable-reboot-on-ctrl-alt-del))
+          (lambda args
+            (let ((err (system-error-errno args)))
+              ;; When in a separate PID namespace, we get EINVAL (see
+              ;; 'reboot_pid_ns' in kernel/pid_namespace.c.)  We get EPERM in
+              ;; a user namespace that lacks CAP_SYS_BOOT.
+              (unless (member err (list EINVAL EPERM))
+                (apply throw args))))))
 
       ;; Stop everything when we get SIGINT.
       (sigaction SIGINT