Archive::Zip::MemberRead - A wrapper that lets you read Zip archive members as if they were files.

  use Archive::Zip;
  use Archive::Zip::MemberRead;
  $zip = Archive::Zip->new("file.zip");
  $fh  = Archive::Zip::MemberRead->new($zip, "subdir/abc.txt");
  while (defined($line = $fh->getline()))
  {
      print $fh->input_line_number . "#: $line\n";
  }

  $read = $fh->read($buffer, 32*1024);
  print "Read $read bytes as :$buffer:\n";

package Archive::Zip::MemberRead;

use strict;

use Archive::Zip qw( :ERROR_CODES :CONSTANTS );

use vars qw{$VERSION};

my $nl;

BEGIN {
    $VERSION = '1.30';
    $VERSION = eval $VERSION;
     # Requirement for newline conversion. Should check for e.g., DOS and OS/2 as well, but am too lazy.
     $nl = $^O eq 'MSWin32' ? "\r\n" : "\n";
}

sub Archive::Zip::Member::readFileHandle {
    return Archive::Zip::MemberRead->new( shift() );
}

sub new {
    my ( $class, $zip, $file ) = @_;
    my ( $self, $member );

    if ( $zip && $file )    # zip and filename, or zip and member
    {
        $member = ref($file) ? $file : $zip->memberNamed($file);
    }
    elsif ( $zip && !$file && ref($zip) )    # just member
    {
        $member = $zip;
    }
    else {
        die(
'Archive::Zip::MemberRead::new needs a zip and filename, zip and member, or member'
        );
    }

    $self = {};
    bless( $self, $class );
    $self->set_member($member);
    return $self;
}

sub set_member {
    my ( $self, $member ) = @_;

    $self->{member} = $member;
    $self->set_compression(COMPRESSION_STORED);
    $self->rewind();
}

sub set_compression {
    my ( $self, $compression ) = @_;
    $self->{member}->desiredCompressionMethod($compression) if $self->{member};
}

sub setLineEnd {
    shift;
    $nl = shift;
}

sub rewind {
    my $self = shift;

    $self->_reset_vars();
    $self->{member}->rewindData() if $self->{member};
}

sub _reset_vars {
    my $self = shift;

    $self->{line_no} = 0;
    $self->{at_end}  = 0;

    delete $self->{buffer};
}

sub input_record_separator {
    my $self = shift;
     if (@_) {
         $self->{sep}    = shift;
         $self->{sep_re} = _sep_as_re($self->{sep}); # Cache the RE as an optimization
     }
     return exists $self->{sep} ? $self->{sep} : $/;
}

# Return the input_record_separator in use as an RE fragment
# Note that if we have a per-instance input_record_separator
# we can just return the already converted value. Otherwise,
# the conversion must be done on $/ every time since we cannot
# know whether it has changed or not.
sub _sep_re {
    my $self = shift;
    # Important to phrase this way: sep's value may be undef.
    return exists $self->{sep} ? $self->{sep_re} : _sep_as_re($/);
}

# Convert the input record separator into an RE and return it.
sub _sep_as_re {
    my $sep = shift;
    if (defined $sep) {
        if ($sep eq '') {
            return "(?:$nl){2,}";
        } else {
            $sep =~ s/\n/$nl/og;
            return quotemeta $sep;
        }
    } else {
        return undef;
    }
}

sub input_line_number {
    my $self = shift;
    return $self->{line_no};
}

sub close {
    my $self = shift;

    $self->_reset_vars();
    $self->{member}->endRead();
}

sub buffer_size {
    my ( $self, $size ) = @_;

    if ( !$size ) {
        return $self->{chunkSize} || Archive::Zip::chunkSize();
    }
    else {
        $self->{chunkSize} = $size;
    }
}

sub getline {
    my $self = shift;
    my $size = $self->buffer_size();
    my $sep  = $self->_sep_re();

    for (;;) {
        if (   $sep
            && defined($self->{buffer})
            && $self->{buffer} =~ s/^(.*?)$sep//s
           ) {
            $self->{line_no}++;
            return $1;
        } elsif ($self->{at_end}) {
            $self->{line_no}++ if $self->{buffer};
            return delete $self->{buffer};
        }
        my ($temp,$status) = $self->{member}->readChunk($size);
        if ($status != AZ_OK && $status != AZ_STREAM_END) {
            die "ERROR: Error reading chunk from archive - $status";
        }
        $self->{at_end} = $status == AZ_STREAM_END;
        $self->{buffer} .= $$temp;
    }
}

#
# All these $_ are required to emulate read().
#
sub read {
    my $self = $_[0];
    my $size = $_[2];
    my ( $temp, $status, $ret );

    ( $temp, $status ) = $self->{member}->readChunk($size);
    if ( $status != AZ_OK && $status != AZ_STREAM_END ) {
        $_[1] = undef;
        $ret = undef;
    }
    else {
        $_[1] = $$temp;
        $ret = length($$temp);
    }
    return $ret;
}

1;