Improve sorting of entries in delete list

...sort them in order of most significant domain to least. That is,
sort on TLD first and hostname last. This is particularly helpful
when sorting in-addr.arpa domains.

Signed-off-by: Erik Rossen <rossen@rossen.ch>
Signed-off-by: Jeff Layton <jlayton@redhat.com>

diff --git a/dnsdusty b/dnsdusty
index ba071b2e854533d60e3c2b2f46d9cee57f400f00..ce947dbcdcc47ede181a6d7360a4b6785291b25f 100755 (executable)
--- a/dnsdusty
+++ b/dnsdusty
@@ -73,16 +73,30 @@ sub get_resolver_object {
     return \$res;
 }
 
+# returns a sort value which is an upper case, big-endian (i.e. TLD first),
+# zero-padded string of each domain name
+sub canonicalize_name {
+    # set number of zeros used to pad sequences of decimal digits
+    # NOTE: this is a lazy hack
+    my $nzeros = 10;
+    my $mname = uc($1);  # shift everything to uppercase
+    $mname = join ".", reverse split /\./, $mname;  # make domain big-endian
+    $mname =~ s/\d+/sprintf("%0${nzeros}d",$&)/eg;  # zero-pad all decimal sequences
+    return $mname;
+}
 
 sub zone_transfer {
     my ($res,$zone,$class) = @_;
+    my %mn = (); # hash for munged names of RRs
     my @rr = ();
     my @zonerecs = ${$res}->axfr($zone,$class);
     foreach my $record (@zonerecs) {
        next if ($record->type eq 'SOA');
+       $record->string =~ /(\S+)/; # assume domain name occupies first non-whitespace chars of each record
+       $mn{$record->string} = canonicalize_name($1);
        push (@rr,$record->string);
     }
-    my @sortedrr = sort {uc($a) cmp uc($b)} @rr;
+    my @sortedrr = sort { $mn{$a} cmp $mn{$b} } @rr;
     return \@sortedrr;
 }