This page hosts a formal specification of .pak file format of Dune 2 game engine using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.
All parsing code for Ruby generated by Kaitai Struct depends on the Ruby runtime library. You have to install it before you can parse data.
The Ruby runtime library can be installed from RubyGems:
gem install kaitai-structParse a local file and get structure in memory:
data = Dune2Pak.from_file("path/to/local/file.pak")
Or parse structure from a string of bytes:
bytes = "\x00\x01\x02..."
data = Dune2Pak.new(Kaitai::Struct::Stream.new(bytes))
After that, one can get various attributes from the structure by invoking getter methods like:
data.dir # => get dir
# This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild
require 'kaitai/struct/struct'
unless Gem::Version.new(Kaitai::Struct::VERSION) >= Gem::Version.new('0.9')
raise "Incompatible Kaitai Struct Ruby API: 0.9 or later is required, but you have #{Kaitai::Struct::VERSION}"
end
##
# @see https://moddingwiki.shikadi.net/wiki/PAK_Format_(Westwood) Source
class Dune2Pak < Kaitai::Struct::Struct
def initialize(_io, _parent = nil, _root = self)
super(_io, _parent, _root)
_read
end
def _read
@_raw_dir = @_io.read_bytes(dir_size)
_io__raw_dir = Kaitai::Struct::Stream.new(@_raw_dir)
@dir = Files.new(_io__raw_dir, self, @_root)
self
end
class Files < Kaitai::Struct::Struct
def initialize(_io, _parent = nil, _root = self)
super(_io, _parent, _root)
_read
end
def _read
@files = []
i = 0
while not @_io.eof?
@files << File.new(@_io, self, @_root, i)
i += 1
end
self
end
attr_reader :files
end
class File < Kaitai::Struct::Struct
def initialize(_io, _parent = nil, _root = self, idx)
super(_io, _parent, _root)
@idx = idx
_read
end
def _read
@ofs = @_io.read_u4le
if ofs != 0
@file_name = (@_io.read_bytes_term(0, false, true, true)).force_encoding("ASCII")
end
self
end
def next_ofs0
return @next_ofs0 unless @next_ofs0.nil?
if ofs != 0
@next_ofs0 = _root.dir.files[(idx + 1)].ofs
end
@next_ofs0
end
def next_ofs
return @next_ofs unless @next_ofs.nil?
if ofs != 0
@next_ofs = (next_ofs0 == 0 ? _root._io.size : next_ofs0)
end
@next_ofs
end
def body
return @body unless @body.nil?
if ofs != 0
io = _root._io
_pos = io.pos
io.seek(ofs)
@body = io.read_bytes((next_ofs - ofs))
io.seek(_pos)
end
@body
end
attr_reader :ofs
attr_reader :file_name
attr_reader :idx
end
def dir_size
return @dir_size unless @dir_size.nil?
_pos = @_io.pos
@_io.seek(0)
@dir_size = @_io.read_u4le
@_io.seek(_pos)
@dir_size
end
attr_reader :dir
attr_reader :_raw_dir
end