#!/usr/bin/perl

use strict;
use GDBM_File;

my $dirprefix = "/home/httpd/html/adm/help/";

# if the topic hash exists, kill it
unlink 'fragmentLabels.gdbm' if ( -e $dirprefix . 'fragmentTopics.gdbm' );

tie (my %fragmentLabels, 'GDBM_File', $dirprefix . 'fragmentLabels.gdbm', 1, 0);
my $error = 0;

chdir $dirprefix;

while (<*.tex>) 
{
    my $file;
    $file = $_;
    open F, $file;
    my $contents = join("\n", <F>);
    my $label;
    
    # Search for labels, of the form '\label{labelname}'
    foreach $label ( $contents =~ /\\label\{([^}]*)\}/g )
    {
	if (exists $fragmentLabels{$label} )
	{
	    print "***ERROR: '$label' in both $fragmentLabels{$label} " .
	          "and $file. \n";
	    $error = 1;
	}
	$fragmentLabels{$label} = $file;
    }
}

if ($error == 0)
{
    print "There were no duplicate labels. Database rebuilt.\n";
}
else
{
    print "There were errors. You must correct the duplicate labels.\n";
}

untie %fragmentLabels;