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    my %data; 

    while ($content) { 
        $content =~ s/^(\d+)\x00(\d+)\x00// || 
            return $self->error ("Inconsistent content."); 
        my $keylen = $1; my $valuelen = $2; 
        my $key = substr $content, 0, $keylen; 
        my $value = substr $content, $keylen, $valuelen; 
        substr ($content, 0, $keylen + $valuelen) = "";
        $data{$key} = $value;
    }

    return \%data;
}


sub   armor {   armour (@_) }
sub unarmor { unarmour (@_) }


1;


=head1 NAME

Convert::ASCII::Armour - Convert binary octets into ASCII armoured messages.

=head1 SYNOPSIS

    my $converter = new Convert::ASCII::Armour; 

    my $message   = $converter->armour( 
                        Object   => "FOO RECORD", 
                        Headers  => { 
                                      Table   => "FooBar", 
                                      Version => "1.23", 
                                    },
                        Content  => { 
                                      Key  => "0x8738FA7382", 
                                      Name => "Zoya Hall",
                                      Pic  => "....",  # gif 
                                    },
                        Compress => 1,
                    );

    print $message; 


    -----BEGIN COMPRESSED FOO RECORD-----
    Version: 1.23
    Table: FooBar

    eJwzZzA0Z/BNLS5OTE8NycgsVgCiRIVciIAJg6EJg0tiSaqhsYJvYlFy...
    XnpOZl5qYlJySmpaekZmVnZObl5+QWFRcUlpWXlFZRWXAk7g6OTs4urm...
    Fh4VGaWAR5ehkbGJqZm5hSUeNXWKDsoGcWpaGpq68bba0dWxtTVmDOYM...
    NzuZ
    =MxpZvjkrv5XyhkVCuXmsBQ==
    -----END COMPRESSED FOO RECORD-----


    my $decoded   = $converter->unarmour( $message ) 
                     || die $converter->errstr();
                        

=head1 DESCRIPTION

This module converts hashes of binary octets into ASCII messages suitable
for transfer over 6-bit clean transport channels. The encoded ASCII
resembles PGP's armoured messages, but are in no way compatible with PGP.

=head1 METHODS

=head2 B<new()>

Constructor.

=head2 B<armour()>

Converts a hash of binary octets into an ASCII encoded message. The
encoded message has 4 parts: head and tail strings that act as identifiers
and delimiters, a cluster of headers at top of the message, Base64 encoded
message body and a Base64 encoded MD5 digest of the message body. armour()
takes a hash as argument with following keys:

=over 4

=item B<Object>

An identification string embedded in head and tail strings.

=item B<Content> 

Content is a hashref that contains the binary octets to be encoded. This
hash is serialized, compressed (if specified) and encoded into ASCII with
MIME::Base64.  The result is the body of the encoded message.

=item B<Headers>

Headers is a hashref that contains ASCII headers that are placed at top of
the encoded message. Headers are encoded as RFC822 headers.

=item B<Compress>

A boolean parameter that forces armour() to compress the message body.

=back

=head2 B<unarmour()>

Decodes an armoured ASCII message into the hash provided as argument
to armour(). The hash contains Content, Object, and Headers.
unarmour() performs several consistency checks and returns a non-true
value on failure.

=head2 B<errstr()>

Returns the error message set by unarmour() on failure.

=head1 AUTHOR

Vipul Ved Prakash, E<lt>mail@vipul.netE<gt>