Re: utility functions for handling Distinguished Names

[Norbert K. <nor...@da...>]

Hi Graham,
I put the #xxxx issue in a separate mail.

>> --- Util.pm-0.25_01	Tue Apr 23 20:35:04 2002
>> +++ Util.pm	Tue Apr 23 21:16:17 2002
>> @@ -231,8 +231,8 @@
>
>>  sub canonical_dn($%) {
>> -  my $dn =3D shift or return '';
>> +  my $dn =3D shift;
>> +  return $dn unless $dn; # empty DN or undef
>
>  $dn =3D "0" ?

This is another case to consider.

> This should be  return $dn unless $dn and length $dn;

return $dn if $dn eq '' || !defined $dn ; # empty DN or undef

This handles undef, '' and "0" (leads to an error later).

>>    my %opt =3D @_;
>>
>>    # create array of hash representation
>>    my @rdns;
>>    if ( ref $dn eq 'ARRAY' ) {
>> -    @rdns =3D @{$dn};
>> +    @rdns =3D $opt{reverse} ? reverse @{$dn} : @{$dn};
>>    } else {
>> -    @rdns =3D ldap_explode_dn( $dn ) or return undef; #error condition
>> +    @rdns =3D ldap_explode_dn( $dn, reverse =3D> $opt{reverse} );
>
> Does it really make sense for ldap_explode_dn todo the reverse ?

I added a reverse option to ldap_explode_dn and though it would be a good=20
idea to use it from canonical_dn as well. Am I missing something?

>>  sub ldap_explode_dn($%) {
>> -  my $dn =3D shift or return;
>> +  my @emptydn =3D (); #empty DN array for scalar context
>> +  my $dn =3D shift;
>> +  return wantarray ? [] : \@emptydn if $dn eq '';
>
> This does not make sense. You are returning a scalar ref
> when wantarray is true. Did you mean
>
>   return wantarray ? () : [] if $dn eq '';

I'm not that familar with these elements of Perl so it tell you what a I=20
actually had in mind: The return value of ldap_explode_dn should give the=20
user an indication, whether an invalid DN was passed in. The problem is now =

that the (valid) empty DN '' explodes to an empty array. In the scalar=20
context one can return undef or a reference to an empty array but I don't=20
know to express this in list context.

>>    my %opt =3D @_;
>>
>>    my (@dn, %rdn);
>> +  $dn =3D~ s/^<(.*)>$/$1/; #remove brackets
>
> why ? where is it defined that DNs have <> brackets ?

There is a test case <UID=3Djsmith,O=3Dexample,C=3DUS> in the ldapbis =
document. I=20
don't know where such could be defined. Kurt?

--=20
Norbert Klasen, Dipl.-Inform.
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