gitlab: watcher should take care of sidekiq killed by SIGTERM

The watcher should also watch for signals like SIGTERM killing sidekiq, which
are trapped by sidekiq, with sidekiq exiting successfully (with exit code 0).

Discussion: https://lab.nexedi.com/lab.nexedi.com/lab.nexedi.com/issues/25#note_22085

software/gitlab/software.cfg

@@ -269,7 +269,7 @@ context =
 
 [watcher-sigkill]
 <= binsh
-md5sum  = 2986dcb006dc9e8508ff81f646656131
+md5sum  = 9233f3726a8e7ee39cdfefa10d839c62
 
 [gitlab-export]
 <= binsh

software/gitlab/watcher-sigkill.in

@@ -12,6 +12,7 @@ fi
 prog="$@"
 
 progpid=""
+exitok="0"      # sidekiq traps some signals (SIGTERM, ...) and exits with code 0
 killexit="137"  # = 128 + 9  (exit code of process terminated by SIGKILL)
 
 # make sure to terminate children, when we exit.
@@ -33,7 +34,7 @@ while true; do
     echo "-> $status"
 
     # if program terminated not by SIGKILL - exit
-    if [ "$status" != "$killexit" ] ; then
+    if [[ "$status" != "$killexit" && "$status" != "$exitok" ]] ; then
         echo "exit $status"
         exit "$status"
     fi