Merge pull request #389 from Googulator/after

After bootstrap, drop to a shell if needed, then shut down cleanly

steps/improve/after.sh

@@ -0,0 +1,24 @@
+#!/bin/sh
+#
+# SPDX-FileCopyrightText: 2024 Gábor Stefanik <netrolller.3d@gmail.com>
+#
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# After bootstrap, drop to a shell if needed, then shut down cleanly.
+
+. /steps/bootstrap.cfg
+. /steps/env
+
+if [ "${INTERACTIVE}" = True ]; then
+    env - PATH=${PREFIX}/bin PS1="\w # " bash -i
+fi
+
+if [ "${CHROOT}" = False ]; then
+    # ignore errors due to fstab or swapfile not existing
+    swapoff -a &> /dev/null || true
+    sync
+    # sysrq to avoid device busy; then mount to wait for it to finish
+    echo u > /proc/sysrq_trigger
+    mount -o remount,ro /
+    echo o > /proc/sysrq_trigger # power off
+fi