This page hosts a formal specification of .dat file format of Fallout 2 using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.
All parsing code for Python generated by Kaitai Struct depends on the Python runtime library. You have to install it before you can parse data.
The Python runtime library can be installed from PyPI:
python3 -m pip install kaitaistructParse a local file and get structure in memory:
data = Fallout2Dat.from_file("path/to/local/file.dat")
Or parse structure from a bytes:
from kaitaistruct import KaitaiStream, BytesIO
raw = b"\x00\x01\x02..."
data = Fallout2Dat(KaitaiStream(BytesIO(raw)))
After that, one can get various attributes from the structure by invoking getter methods like:
data.footer # => get footer
# This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild
import kaitaistruct
from kaitaistruct import KaitaiStruct, KaitaiStream, BytesIO
from enum import Enum
import zlib
if getattr(kaitaistruct, 'API_VERSION', (0, 9)) < (0, 9):
raise Exception("Incompatible Kaitai Struct Python API: 0.9 or later is required, but you have %s" % (kaitaistruct.__version__))
class Fallout2Dat(KaitaiStruct):
class Compression(Enum):
none = 0
zlib = 1
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._read()
def _read(self):
pass
class Pstr(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._read()
def _read(self):
self.size = self._io.read_u4le()
self.str = (self._io.read_bytes(self.size)).decode(u"ASCII")
class Footer(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._read()
def _read(self):
self.index_size = self._io.read_u4le()
self.file_size = self._io.read_u4le()
class Index(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._read()
def _read(self):
self.file_count = self._io.read_u4le()
self.files = []
for i in range(self.file_count):
self.files.append(Fallout2Dat.File(self._io, self, self._root))
class File(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._read()
def _read(self):
self.name = Fallout2Dat.Pstr(self._io, self, self._root)
self.flags = KaitaiStream.resolve_enum(Fallout2Dat.Compression, self._io.read_u1())
self.size_unpacked = self._io.read_u4le()
self.size_packed = self._io.read_u4le()
self.offset = self._io.read_u4le()
@property
def contents_raw(self):
if hasattr(self, '_m_contents_raw'):
return self._m_contents_raw
if self.flags == Fallout2Dat.Compression.none:
io = self._root._io
_pos = io.pos()
io.seek(self.offset)
self._m_contents_raw = io.read_bytes(self.size_unpacked)
io.seek(_pos)
return getattr(self, '_m_contents_raw', None)
@property
def contents_zlib(self):
if hasattr(self, '_m_contents_zlib'):
return self._m_contents_zlib
if self.flags == Fallout2Dat.Compression.zlib:
io = self._root._io
_pos = io.pos()
io.seek(self.offset)
self._raw__m_contents_zlib = io.read_bytes(self.size_packed)
self._m_contents_zlib = zlib.decompress(self._raw__m_contents_zlib)
io.seek(_pos)
return getattr(self, '_m_contents_zlib', None)
@property
def contents(self):
if hasattr(self, '_m_contents'):
return self._m_contents
if ((self.flags == Fallout2Dat.Compression.zlib) or (self.flags == Fallout2Dat.Compression.none)) :
self._m_contents = (self.contents_zlib if self.flags == Fallout2Dat.Compression.zlib else self.contents_raw)
return getattr(self, '_m_contents', None)
@property
def footer(self):
if hasattr(self, '_m_footer'):
return self._m_footer
_pos = self._io.pos()
self._io.seek((self._io.size() - 8))
self._m_footer = Fallout2Dat.Footer(self._io, self, self._root)
self._io.seek(_pos)
return getattr(self, '_m_footer', None)
@property
def index(self):
if hasattr(self, '_m_index'):
return self._m_index
_pos = self._io.pos()
self._io.seek(((self._io.size() - 8) - self.footer.index_size))
self._m_index = Fallout2Dat.Index(self._io, self, self._root)
self._io.seek(_pos)
return getattr(self, '_m_index', None)