*-test.*: Add script for reboots, maybe.

Signed-off-by: James Antill <james@and.org>

files/scripts/reboot-decider.sh

@@ -0,0 +1,57 @@
+#! /bin/sh -e
+
+# Simple script to maybe reboot the machine.
+
+#  We want to reboot if:
+#
+# * There's a new kernel installed.
+#
+#  ...also if we are running from cron, we probably only want to reboot if
+# there's nobody logged into the machine (Eg. the *-test.* machines, or
+# maybe someone debugging a staging machine).
+
+CUR_KERNEL="$(uname -r)"
+
+_DEF_KERN_PATH="$(grubby --default-kernel)"
+NXT_KERNEL=$(basename "$_DEF_KERN_PATH" | sed 's/^vmlinuz-//')
+
+# How many users are logged into the machine.
+USER_COUNT=$(who | wc -l)
+
+
+function err {
+  echo "$@" >&2
+}
+
+function maybe_reboot {
+  if [ "x$CUR_KERNEL" != "x$NXT_KERNEL" ]; then
+    reboot
+  fi
+}
+
+
+case "$1" in
+  info)
+    echo "-------- Kernel Status Check --------"
+    echo "Running: $CUR_KERNEL"
+    if [ "x$CUR_KERNEL" != "x$NXT_KERNEL" ]; then
+    echo "   Next: $NXT_KERNEL"
+    fi
+    echo "-------------------------------------"
+    echo "Users: $USER_COUNT"
+    ;;
+
+  maybe-reboot)
+    maybe_reboot
+    ;;
+
+  maybe-cron-reboot|cron-maybe-reboot)
+    if [ "$USER_COUNT" -eq 0 ]; then
+      maybe_reboot
+    fi
+    ;;
+
+  *)
+    err "Usage: $0 info | maybe-reboot | cron-maybe-reboot"
+    exit 1
+esac