abs2rel.pl

#!env perl

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# Version: MPL 1.1/GPL 2.0/LGPL 2.1
#
# The contents of this file are subject to the Mozilla Public License Version
# 1.1 (the "License"); you may not use this file except in compliance with
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# The Original Code is mozilla.org Code.
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# The Initial Developer of the Original Code is
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# the Initial Developer. All Rights Reserved.
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use File::Spec::Unix;
use strict;

print "Usage: $0 dest_path start_path\n" if ($#ARGV+1 != 2);
my $finish = my_canonpath(shift);
my $start = my_canonpath(shift);

my $res = File::Spec::Unix->abs2rel($finish, $start);

#print STDERR "abs2rel($finish,$start) = $res\n";
print "$res\n";

sub my_canonpath($) {
    my ($file) = @_;
    my (@inlist, @outlist, $dir);

    # Do what File::Spec::Unix->no_upwards should do
    my @inlist = split(/\//, File::Spec::Unix->canonpath($file));
    foreach $dir (@inlist) {
	if ($dir eq '..') {
	    pop @outlist;
	} else {
	    push @outlist, $dir;
	}
    }
    $file = join '/',@outlist;
    return $file;
}