Magisk/app/src/full/java/com/topjohnwu/magisk/receivers/RebootReceiver.java

package com.topjohnwu.magisk.receivers;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;

import com.topjohnwu.superuser.Shell;

public class RebootReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        Shell.su("/system/bin/reboot").submit();
    }
}