1 files changed, 54 insertions, 0 deletions
diff --git a/extra/scripts/relative_path.sh b/extra/scripts/relative_path.sh
new file mode 100755
index 000000000..380344a63
--- /dev/null
+++ b/extra/scripts/relative_path.sh
@@ -0,0 +1,54 @@
+#! /bin/sh
+# This script computes a relative pathname from $1 to $2
+# They are assumed to not contain . or .. pathname components,
+# but if both directories exist and cd/pwd canonicalizes pathnames,
+# this shouldn't matter.  PWD_CMD may be set to some pwd command that does.
+
+# Copyright 2003 Alexandre Oliva <aoliva@redhat.com>
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+# General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software Foundation, Inc.,
+# 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+
+from=`(cd $1 > /dev/null && ${PWD_CMD-pwd} || echo $1) 2>/dev/null | sed 's,//*,/,g;s,/*$,,'`
+target=`(cd $2 > /dev/null && ${PWD_CMD-pwd} || echo $2) 2>/dev/null | sed 's,//*,/,g;s,/*$,,'`
+
+case $from in /* | "") ;; *) from=`${PWD_CMD-pwd}`/$from ;; esac
+case $target in /* | "") ;; *) target=`${PWD_CMD-pwd}`/$target ;; esac
+
+case $target in
+"$from" | "$from/"*)
+  dots=`echo $from | sed s,.,.,g`
+  echo $target | sed "s,^$dots/*,,;s,[^/]$,&/,"
+  exit 0
+  ;;
+esac
+
+case $from in
+"$target/"*)
+  dots=`echo $target | sed s,.,.,g`
+  echo $from/ | sed "s,^$dots/*,,;s,[^/]$,&/,;s,[^/]*/*,../,g;s,[^/]$,&/,"
+  exit 0
+  ;;
+esac
+
+prefix=`echo $from///$target | sed 's,\(\(/[^/]*\)*\).*///\1.*,\1,'`
+dots=`echo $prefix | sed s,.,.,g`
+from=`echo $from | sed "s,^$dots,,"`
+target=`echo $target | sed "s,^$dots,,"`
+
+from=`echo $from | sed 's,[^/][^/]*,..,g;s,.$,&/,'`
+echo ${from}$target/
+
+exit 0