l4re-base-25.08.0

src/l4/mk/rel2abs.sh

@@ -0,0 +1,72 @@
+#! /usr/bin/env bash
+#
+# Convert relative path to absolute one
+#
+# Adam Lackorzynski <adam@os.inf.tu-dresden.de>
+#
+
+help()
+{
+  echo PWD=\$PWD $0 relpath1 [relpath2 [..]]
+  exit $1
+}
+
+convertpath()
+{
+  relpath=$1
+  basepath=$PWD
+  # sanity checks
+  [ -z "$relpath" -o -z "$basepath" ] && help 1
+  [ "${basepath#/}" = "${basepath}" ] && help 1
+  [ "${basepath/\/..\//}" = "${basepath}" ] || help 1
+  [ "${basepath/\/.\//}" = "${basepath}" ] || help 1
+  [ "${basepath/%\/../}" = "${basepath}" ] || help 1
+  [ "${basepath/%\/./}" = "${basepath}" ] || help 1
+
+
+  # remove slashes at the end
+  while [ "${relpath%/}" != "${relpath}" ];
+  do relpath="${relpath%/}"; done
+
+  # remove double/multi slashes
+  while [ "${relpath/\/\///}" != "${relpath}" ];
+  do relpath=${relpath/\/\///}; done
+
+  # is relpath relative?
+  if [ "${relpath#/}" != "${relpath}" ]; then
+    basepath=''
+    relpath=${relpath#/}
+  fi
+
+  relpath="$relpath/"
+
+  while [ -n "$relpath" ];
+  do
+    elem=${relpath%%/*}
+    relpath=${relpath#*/}
+
+    case $elem in
+      .) # skip
+	;;
+      ..)
+	 basepath=${basepath%/*}
+	;;
+      *)
+	 basepath=$basepath/$elem
+	;;
+    esac
+
+  done
+
+  [ -z "$basepath" ] && basepath=/$basepath
+
+  echo $basepath
+}
+
+while [ -n "$1" ];
+do
+  convertpath $1
+  shift
+done
+
+exit 0