1 files changed, 45 insertions, 0 deletions
diff --git a/scripts/ptxd_abs2rel.sh b/scripts/ptxd_abs2rel.sh
new file mode 100755
index 0000000..d122806
--- /dev/null
+++ b/scripts/ptxd_abs2rel.sh
@@ -0,0 +1,45 @@
+#!/bin/bash
+#
+# Copyright (C) 2009 by Marc Kleine-Budde <mkl@pengutronix.de>
+# See CREDITS for details about who has contributed to this project.
+#
+# For further information about the PTXdist project and license conditions
+# see the README file.
+#
+
+ptxd_abs2rel() {
+    local from from_parts to to_parts max orig_IFS
+
+    [ ${#} -eq 2 ] || { echo "supply exactly two paths" >&2; exit 1; }
+
+    from="${1}"
+    to="${2}"
+
+    orig_IFS="${IFS}"
+    IFS="/"
+    from_parts=(${from#/})
+    to_parts=(${to#/})
+
+    if [ ${#from_parts[@]} -gt ${#to_parts[@]} ]; then
+	max=${#from_parts[@]}
+    else
+	max=${#to_parts[@]}
+    fi
+
+    for ((i = 0; i < ${max}; i++)); do
+	from="${from_parts[i]}"
+	to="${to_parts[i]}"
+
+	if [ "${from}" = "${to}" ]; then
+	    unset from_parts[$i]
+	    unset to_parts[$i]
+	elif [ -n "${from}" ]; then
+	    from_parts[$i]=".."
+	fi
+    done
+
+    echo "${from_parts[*]}${from_parts[*]:+/}${to_parts[*]}"
+    IFS="${orig_IFS}"
+}
+
+ptxd_abs2rel "${@}"