/ 
Archive-Lha-0.02
/ Archive::Lha::Decode

NAME

Archive::Lha::Decode

SYNOPSIS

# don't forget :raw, or eol might be converted implicitly
open my $fh, '>:raw', $header->pathname;
binmode $fh;
$stream->seek( $header->data_top );
my $decoder = Archive::Lha::Decode->new(
  header => $header,
  read   => sub { $stream->read(@_) },
  write  => sub { print $fh @_ },
)
my $crc16 = $decoder->decode;
croak "crc mismatch" if $crc16 != $header->crc16;

DESCRIPTION

This is used to decode/extract an archived file from the stream. Actually this ::Decode class is a factory and decoding is done by a delegated class according to the header's "method" property.

All of the ::Decode subclasses require read/write callbacks. Read callback should take a byte length as an argument, and return the bytes of the length from a file or a string. Write callback should take a part of the decoded (probably binary) string as an argument, and the rest is up to you. You may want to write it down in a file as shown above, or maybe append it to a string to store in a database after finished. You may want to encode it first, or throw it away if the string contains unprintable binary. You may want to use a temporary file. You may want to update a progress indicator. Do whatever you want.

METHODS

new

takes an Archive::Lha::Header object, and read/write callbacks and creates an appropriate object.

decode

does the decoding stuff and returns CRC-16 of the decoded string. The decoded string itself is passed to the write callback while decoding (step by step).

AUTHOR

Kenichi Ishigaki, <ishigaki@cpan.org>

COPYRIGHT AND LICENSE

Copyright (C) 2007 by Kenichi Ishigaki.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.