# extract ASN.1 from an IETF RFC
#
# usage : rfcExtractAsn1 <url>

if (@ARGV < 1) {
    print "usage: rfcExtractAsn1.pl <url>\n";
    exit (-1);
}

use LWP::Simple;

$pageURL=$ARGV[0]; # for example, http://tools.ietf.org/html/rfc5911

$simplePage=get($pageURL); 

$simplePage =~ s/\<span\sclass\=\"grey\"\>.+\<\/span\>//g;
$simplePage =~ s/\<\/pre\>\<pre\sclass\=\'newpage\'\>\<a.+\<\/a\>//g;
$simplePage =~ s/\&amp\;/&/g;

while (1) {
    if ($simplePage =~ m/[A-Z][\w\-]*\s+\{[\w\(\)\-\s]+\}\s+DEFINITIONS[\w\s]+\:\:\=\s+BEGIN.*?\bEND/s) {
	print "$&\n";
	$simplePage = $';
        print ("\n\n");
    }
    else {
#       print "not matched\n";
        last;
    }
}
print ("\n\n");

# print $simplePage;