diff --git a/tools/xen/scripts/on_exit.sh b/tools/xen/scripts/on_exit.sh
new file mode 100755
index 0000000..a4db39c
--- /dev/null
+++ b/tools/xen/scripts/on_exit.sh
@@ -0,0 +1,24 @@
+#!/bin/bash
+
+set -e
+set -o xtrace
+
+declare -a on_exit_hooks
+
+on_exit()
+{
+    for i in $(seq $((${#on_exit_hooks[*]} - 1)) -1 0)
+    do
+        eval "${on_exit_hooks[$i]}"
+    done
+}
+
+add_on_exit()
+{
+    local n=${#on_exit_hooks[*]}
+    on_exit_hooks[$n]="$*"
+    if [[ $n -eq 0 ]]
+    then
+        trap on_exit EXIT
+    fi
+}