package IO::Compress::Zlib::Extra; require 5.004 ; use strict ; use warnings; use bytes; our ($VERSION, @ISA, @EXPORT_OK, %EXPORT_TAGS); $VERSION = '2.008'; use IO::Compress::Gzip::Constants 2.008 ; sub ExtraFieldError { return $_[0]; return "Error with ExtraField Parameter: $_[0]" ; } sub validateExtraFieldPair { my $pair = shift ; my $strict = shift; my $gzipMode = shift ; return ExtraFieldError("Not an array ref") unless ref $pair && ref $pair eq 'ARRAY'; return ExtraFieldError("SubField must have two parts") unless @$pair == 2 ; return ExtraFieldError("SubField ID is a reference") if ref $pair->[0] ; return ExtraFieldError("SubField Data is a reference") if ref $pair->[1] ; # ID is exactly two chars return ExtraFieldError("SubField ID not two chars long") unless length $pair->[0] == GZIP_FEXTRA_SUBFIELD_ID_SIZE ; # Check that the 2nd byte of the ID isn't 0 return ExtraFieldError("SubField ID 2nd byte is 0x00") if $strict && $gzipMode && substr($pair->[0], 1, 1) eq "\x00" ; return ExtraFieldError("SubField Data too long") if length $pair->[1] > GZIP_FEXTRA_SUBFIELD_MAX_SIZE ; return undef ; } sub parseRawExtra { my $data = shift ; my $extraRef = shift; my $strict = shift; my $gzipMode = shift ; #my $lax = shift ; #return undef # if $lax ; my $XLEN = length $data ; return ExtraFieldError("Too Large") if $XLEN > GZIP_FEXTRA_MAX_SIZE; my $offset = 0 ; while ($offset < $XLEN) { return ExtraFieldError("Truncated in FEXTRA Body Section") if $offset + GZIP_FEXTRA_SUBFIELD_HEADER_SIZE > $XLEN ; my $id = substr($data, $offset, GZIP_FEXTRA_SUBFIELD_ID_SIZE); $offset += GZIP_FEXTRA_SUBFIELD_ID_SIZE; my $subLen = unpack("v", substr($data, $offset, GZIP_FEXTRA_SUBFIELD_LEN_SIZE)); $offset += GZIP_FEXTRA_SUBFIELD_LEN_SIZE ; return ExtraFieldError("Truncated in FEXTRA Body Section") if $offset + $subLen > $XLEN ; my $bad = validateExtraFieldPair( [$id, substr($data, $offset, $subLen)], $strict, $gzipMode ); return $bad if $bad ; push @$extraRef, [$id => substr($data, $offset, $subLen)] if defined $extraRef;; $offset += $subLen ; } return undef ; } sub mkSubField { my $id = shift ; my $data = shift ; return $id . pack("v", length $data) . $data ; } sub parseExtraField { my $dataRef = $_[0]; my $strict = $_[1]; my $gzipMode = $_[2]; #my $lax = @_ == 2 ? $_[1] : 1; # ExtraField can be any of # # -ExtraField => $data # # -ExtraField => [$id1, $data1, # $id2, $data2] # ... # ] # # -ExtraField => [ [$id1 => $data1], # [$id2 => $data2], # ... # ] # # -ExtraField => { $id1 => $data1, # $id2 => $data2, # ... # } if ( ! ref $dataRef ) { return undef if ! $strict; return parseRawExtra($dataRef, undef, 1, $gzipMode); } #my $data = $$dataRef; my $data = $dataRef; my $out = '' ; if (ref $data eq 'ARRAY') { if (ref $data->[0]) { foreach my $pair (@$data) { return ExtraFieldError("Not list of lists") unless ref $pair eq 'ARRAY' ; my $bad = validateExtraFieldPair($pair, $strict, $gzipMode) ; return $bad if $bad ; $out .= mkSubField(@$pair); } } else { return ExtraFieldError("Not even number of elements") unless @$data % 2 == 0; for (my $ix = 0; $ix <= length(@$data) -1 ; $ix += 2) { my $bad = validateExtraFieldPair([$data->[$ix], $data->[$ix+1]], $strict, $gzipMode) ; return $bad if $bad ; $out .= mkSubField($data->[$ix], $data->[$ix+1]); } } } elsif (ref $data eq 'HASH') { while (my ($id, $info) = each %$data) { my $bad = validateExtraFieldPair([$id, $info], $strict, $gzipMode); return $bad if $bad ; $out .= mkSubField($id, $info); } } else { return ExtraFieldError("Not a scalar, array ref or hash ref") ; } return ExtraFieldError("Too Large") if length $out > GZIP_FEXTRA_MAX_SIZE; $_[0] = $out ; return undef; } 1; __END__