#!/bin/sh

# rellns-sh - Simplified ln program to generate relative symbolic link.

# Copyright (C) 1996-2018 Free Software Foundation, Inc.

# Written by Ulrich Drepper <drepper@cygnus.com>, October 1996

#

# 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, 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, see <http://www.gnu.org/licenses/>.

# With -p, instead of creating the link print the computed relative link

# name.

do_print=false

case $1 in

  -p)

    do_print=true

    shift

    ;;

esac

if test $# -ne 2; then

  echo "Usage: rellns [-p] SOURCE DEST" >&2

  exit 1

fi

# Make both paths absolute.

if test -d $1; then

  to=`cd $1 && pwd -P`

else

  temp=`echo $1 | sed 's%/*[^/]*$%%'`

  if test -z "$temp"; then

    to=`pwd -P`

  else

    to=`cd $temp && pwd -P`

  fi

  to="$to/`echo $1 | sed 's%.*/\([^/][^/]*\)$%\1%'`"

fi

to=`echo $to | sed 's%^/%%'`

if test -d $2; then

  from=`echo $2 | sed 's%/*$%%'`

else

  from=`echo $2 | sed 's%/*[^/]*$%%'`

fi

if test -z "$from"; then

  from=`pwd -P | sed 's%^/%%'`

else

  from=`cd $from && pwd -P | sed 's%^/%%'`

fi

while test -n "$to" && test -n "$from"; do

  preto=`echo $to | sed 's%^\([^/]*\)/.*%\1%'`

  prefrom=`echo $from | sed 's%^\([^/]*\)/.*%\1%'`

  test "$preto" != "$prefrom" && break

  to=`echo $to | sed 's%^[^/]*/*\(.*\)$%\1%'`

  from=`echo $from | sed 's%^[^/]*/*\(.*\)$%\1%'`

done

while test -n "$from"; do

  rfrom="../$rfrom"

  from=`echo $from | sed 's%^[^/]*/*%%'`

done

if $do_print; then

  echo "$rfrom$to"

else

  ln -s $rfrom$to $2

fi