#!/usr/bin/perl -w
#
# Copyright 1999 Clark Cooper <coopercc@netheaven.com>
# All rights reserved.
#
# This program is free software; you can redistribute it and/or
# modify it under the same terms as Perl itself.
#
# $Revision: 1.3 $
#
# $Date: 2000/05/22 04:00:32 $
#
#	This program take an XML document (either on standard input or
#	from a filename supplied as an argument) and generates corresponding
#	canonical XML document on the standard output. The definition of
#	"Canonical XML" that I'm using is taken from the working draft
#	published by W3C on 19-Jan-2000:
#
#		http://www.w3.org/TR/2000/WD-xml-c14n-20000119.html
#
#	The latest version of this document is at:
#
#		http://www.w3.org/TR/xml-c14n
#

use XML::Parser;

my $indoctype = 0;
my $inroot = 0;
my $p = new XML::Parser(ErrorContext  => 2,
			Namespaces    => 1,
			ParseParamEnt => 1,
			Handlers      => {Start => \&sthndl,
					  End   => \&endhndl,
					  Char  => \&chrhndl,
					  Proc  => \&proc,
					  Doctype => sub {$indoctype = 1},
					  DoctypeFin => sub {$indoctype = 0}
					 }
			);

my $file = shift;
if (defined $file) {
  $p->parsefile($file);
}
else {
  $p->parse(*STDIN);
}

################
## End main
################

sub sthndl {
  my $xp = shift;
  my $el = shift;

  $inroot = 1 unless $inroot;
  my $ns_index = 1;

  my $elns = $xp->namespace($el);
  if (defined $elns) {
    my $pfx = 'n' . $ns_index++;
    print "<$pfx:$el xmlns:$pfx=\"$elns\"";
  }
  else {
    print "<$el";
  }

  if (@_) {
    for (my $i = 0; $i < @_; $i += 2) {
      my $nm = $_[$i];
      my $ns = $xp->namespace($nm);
      $_[$i] = defined($ns) ? "$ns\01$nm" : "\01$nm";
    }

    my %atts = @_;
    my @ids = sort keys %atts;
    foreach my $id (@ids) {
      my ($ns, $nm) = split(/\01/, $id);
      my $val = $xp->xml_escape($atts{$id}, '"', "\x9", "\xA", "\xD");
      if (length($ns)) {
	my $pfx = 'n' . $ns_index++;
	print " $pfx:$nm=\"$val\" xmlns:$pfx=\"$ns\"";
      }
      else {
	print " $nm=\"$val\"";
      }
    }
  }

  print '>';
}  # End sthndl

sub endhndl {
  my ($xp, $el) = @_;

  my $nm = $xp->namespace($el) ? "n1:$el" : $el;
  print "</$nm>";
  if ($xp->depth == 0) {
    $inroot = 0;
    print "\n";
  }
}  # End endhndl

sub chrhndl {
  my ($xp, $data) = @_;

  print $xp->xml_escape($data, '>', "\xD");
}  # End chrhndl

sub proc {
  my ($xp, $target, $data) = @_;

  unless ($indoctype) {
    print "<?$target $data?>";
    print "\n" unless $inroot;
  }
}

# Tell emacs that this is really a perl script
#Local Variables:
#Mode: perl
#End: