scripts/relpath.awk

   1 #!/usr/bin/awk -f
   2 #
   3 # Copyright (C) 2010 Red Hat, Inc. All rights reserved.
   4 #
   5 # This file is part of LVM2.
   6 #
   7 # This copyrighted material is made available to anyone wishing to use,
   8 # modify, copy, or redistribute it subject to the terms and conditions
   9 # of the GNU General Public License v.2.
  10 #
  11 # You should have received a copy of the GNU General Public License
  12 # along with this program; if not, write to the Free Software Foundation,
  13 # Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  14
  15 # relpath.awk: Script is used to calculate relative path
  16 #              between two real absolute paths.
  17 #
  18 # echo /a/b/c/d  /a/b/e/f | relpath.awk
  19 # -> ../../e/f/
  20
  21 {
  22         length_from = split($1, from, "/");
  23         length_to = split($2, to, "/") ;
  24         l = 1;
  25         while (l <= length_from && l <= length_to && from[l] == to[l])
  26                 l++;
  27         for (i = l; i <= length_from && length(from[i]); i++) {
  28                 if (i > l)
  29                         p = sprintf("%s/", p);
  30                 p = sprintf("%s..", p);
  31         }
  32         for (i = l; i <= length_to && length(to[i]); i++) {
  33                 if (length(p) > 0)
  34                         p = sprintf("%s/", p);
  35                 p = sprintf("%s%s", p, to[i]);
  36         }
  37         if (length(p))
  38                 p = sprintf("%s/", p);
  39         print p
  40 }