File Coverage

blib/lib/Encode/Unicode/UTF7.pm

Criterion	Covered	Total	%
statement	52	59	88.1
branch	16	26	61.5
condition			n/a
subroutine	9	10	90.0
pod	3	3	100.0
total	80	98	81.6

#
# $Id: UTF7.pm,v 2.10 2017/06/10 17:23:50 dankogai Exp $
#
package Encode::Unicode::UTF7;
use strict;
use warnings;
use parent qw(Encode::Encoding);
__PACKAGE__->Define('UTF-7');
our $VERSION = do { my @r = ( q$Revision: 2.10 $ =~ /\d+/g ); sprintf "%d." . "%02d" x $#r, @r };
use MIME::Base64;
use Encode qw(find_encoding);

#
# Algorithms taken from Unicode::String by Gisle Aas
#

our $OPTIONAL_DIRECT_CHARS = 1;
my $specials = quotemeta "\'(),-./:?";
$OPTIONAL_DIRECT_CHARS
  and $specials .= quotemeta "!\"#$%&*;<=>@[]^_`{|}";

# \s will not work because it matches U+3000 DEOGRAPHIC SPACE
# We use qr/[\n\r\t\ ] instead
my $re_asis    = qr/(?:[\n\r\t\ A-Za-z0-9$specials])/;
my $re_encoded = qr/(?:[^\n\r\t\ A-Za-z0-9$specials])/;
my $e_utf16    = find_encoding("UTF-16BE");

sub needs_lines { 1 }

sub encode($$;$) {
    my ( $obj, $str, $chk ) = @_;
    return undef unless defined $str;
    my $len = length($str);
    pos($str) = 0;
    my $bytes = substr($str, 0, 0); # to propagate taintedness
    while ( pos($str) < $len ) {
        if ( $str =~ /\G($re_asis+)/ogc ) {
	    my $octets = $1;
	    utf8::downgrade($octets);
	    $bytes .= $octets;
        }
        elsif ( $str =~ /\G($re_encoded+)/ogsc ) {
            if ( $1 eq "+" ) {
                $bytes .= "+-";
            }
            else {
                my $s = $1;
                my $base64 = encode_base64( $e_utf16->encode($s), '' );
                $base64 =~ s/=+$//;
                $bytes .= "+$base64-";
            }
        }
        else {
            die "This should not happen! (pos=" . pos($str) . ")";
        }
    }
    $_[1] = '' if $chk;
    return $bytes;
}

sub decode($$;$) {
    use re 'taint';
    my ( $obj, $bytes, $chk ) = @_;
    return undef unless defined $bytes;
    my $len = length($bytes);
    my $str = substr($bytes, 0, 0); # to propagate taintedness;
    pos($bytes) = 0;
    no warnings 'uninitialized';
    while ( pos($bytes) < $len ) {
        if ( $bytes =~ /\G([^+]+)/ogc ) {
            $str .= $1;
        }
        elsif ( $bytes =~ /\G\+-/ogc ) {
            $str .= "+";
        }
        elsif ( $bytes =~ /\G\+([A-Za-z0-9+\/]+)-?/ogsc ) {
            my $base64 = $1;
            my $pad    = length($base64) % 4;
            $base64 .= "=" x ( 4 - $pad ) if $pad;
            $str .= $e_utf16->decode( decode_base64($base64) );
        }
        elsif ( $bytes =~ /\G\+/ogc ) {
            $^W and warn "Bad UTF7 data escape";
            $str .= "+";
        }
        else {
            die "This should not happen " . pos($bytes);
        }
    }
    $_[1] = '' if $chk;
    return $str;
}
1;
__END__