/ 
Archive-Lha-0.12
/ Archive::Lha

NAME

Archive::Lha - read and extract .LZH/.LHA archives

SYNOPSIS

use Archive::Lha::Header;
use Archive::Lha::Stream::File;
use Archive::Lha::Decode;

my $stream = Archive::Lha::Stream::File->new(file => 'archive.lzh');
while (defined(my $level = $stream->search_header)) {
  my $header = Archive::Lha::Header->new(
    level  => $level,
    stream => $stream,
  );

  # filename decoded from archive charset (auto-detected from OS field)
  print $header->pathname, "\n";

  # or override charset explicitly
  print $header->pathname('cp932', 'utf-8'), "\n";

  $stream->seek($header->data_top);
  my $decoded = '';
  my $decoder = Archive::Lha::Decode->new(
    header => $header,
    read   => sub { $stream->read(@_) },
    write  => sub { $decoded .= join '', @_ },
  );
  my $crc = $decoder->decode;
  die "crc mismatch for " . $header->pathname if $crc != $header->crc16;

  $stream->seek($header->next_header);
}

DESCRIPTION

Archive::Lha reads and extracts LZH/LHA archives, the format historically used by the Amiga LhA archiver and MS-DOS LHA, and still common in Japan and in Amiga software archives.

The module supports header levels 0, 1 and 2, and decompression methods lh0 (stored), lh5, lh6 and lh7. The decompression code is implemented in XS/C, based on LHa for UNIX.

Filename encoding

LHA archives store filenames as raw bytes. The encoding depends on the platform that created the archive. Archive::Lha::Header::pathname() auto-detects the encoding from the OS field in the header:

Amiga (A)       -> ISO-8859-15
MS-DOS/Win (M/w)-> CP1252
Unix (U)        -> UTF-8
Human68K (H)    -> CP932 (Sharp X68000, Japanese)
unknown/level-0 -> Encode::Guess (latin1/latin2/cp932/euc-jp)

The result is always returned as UTF-8. Pass explicit ($from, $to) arguments to pathname() to override:

$header->pathname('cp932', 'utf-8');
$header->pathname('iso-8859-1', 'utf-8');

KNOWN LIMITATIONS

  • Decompression is slower than native tools. Some of the critical code is in XS/C, but large archives may still take longer than tools like lhasa or LHa for UNIX.

  • Creating or modifying archives is not supported — read and extract only.

  • Header level 3 is not supported (it is rarely found in practice).

COMMAND LINE TOOLS

This distribution includes two command line tools:

plha

Lists and extracts archives using Amiga LhA-compatible output formats (l, v, vv, x, t commands). Supports -fc/-tc for charset override.

plhasa

A symlink to plha that activates a lhasa-compatible interface when invoked as plhasa.

ACKNOWLEDGMENTS

The XS/C decompression code is based on LHa for UNIX version 1.14i-ac20050924p1, with modifications for thread-safety and XS integration. Those parts are copyrighted by Nobutaka Watazaki (1993-1995), Tsugio Okamoto (1996-2000?), and Koji Arai (2002-). Kudos also to the broader LHa family authors: Masaru Oki, Yoichi Tagawa, Haruhiko Okumura, Haruyasu Yoshizaki, Kazuhiko Miki and others.

SEE ALSO

https://github.com/jca02266/lha (LHa for UNIX)
https://github.com/fragglet/lhasa (lhasa, read-only LHA tool)
http://lha.sourceforge.jp/ (LHa for UNIX project site, now offline) — archived at https://web.archive.org/web/*/http://lha.sourceforge.jp/
http://lha.sourceforge.jp/history.html (history of LHa for UNIX, now offline) — archived at https://web.archive.org/web/*/http://lha.sourceforge.jp/history.html
http://homepage1.nifty.com/dangan/en/Content/Program/Java/jLHA/Notes/Notes.html (LHa header format details, may be offline) — archived at https://web.archive.org/web/*/http://homepage1.nifty.com/dangan/en/Content/Program/Java/jLHA/Notes/Notes.html
http://oku.edu.mie-u.ac.jp/~okumura/compression/oldstory.html (older history of LHa/LHarc, may be offline) — archived at https://web.archive.org/web/*/http://oku.edu.mie-u.ac.jp/~okumura/compression/oldstory.html

AUTHORS

Kenichi Ishigaki <ishigaki@cpan.org> (original author).

Nicolas Mendoza <mendoza@pvv.ntnu.no> (Amiga support, charset handling, CLI tools, bug fixes).

COPYRIGHT AND LICENSE

Copyright (C) 2007 by Kenichi Ishigaki, unless otherwise noted.

Copyright (C) 2025-2026 by Nicolas Mendoza, for additional modifications.

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