.pak file format of Quake game engine: Python parsing library

Application

Quake game engine

File extension

pak

KS implementation details

License: CC0-1.0

References

This page hosts a formal specification of .pak file format of Quake game engine using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.

Usage

Runtime 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 kaitaistruct

Code

Parse a local file and get structure in memory:

data = QuakePak.from_file("path/to/local/file.pak")

Or parse structure from a bytes:

from kaitaistruct import KaitaiStream, BytesIO

raw = b"\x00\x01\x02..."
data = QuakePak(KaitaiStream(BytesIO(raw)))

After that, one can get various attributes from the structure by invoking getter methods like:

data.magic # => get magic

Python source code to parse .pak file format of Quake game engine

quake_pak.py

# This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild
# type: ignore

import kaitaistruct
from kaitaistruct import KaitaiStruct, KaitaiStream, BytesIO


if getattr(kaitaistruct, 'API_VERSION', (0, 9)) < (0, 11):
    raise Exception("Incompatible Kaitai Struct Python API: 0.11 or later is required, but you have %s" % (kaitaistruct.__version__))

class QuakePak(KaitaiStruct):
    """
    .. seealso::
       Source - https://quakewiki.org/wiki/.pak#Format_specification
    """
    def __init__(self, _io, _parent=None, _root=None):
        super(QuakePak, self).__init__(_io)
        self._parent = _parent
        self._root = _root or self
        self._read()

    def _read(self):
        self.magic = self._io.read_bytes(4)
        if not self.magic == b"\x50\x41\x43\x4B":
            raise kaitaistruct.ValidationNotEqualError(b"\x50\x41\x43\x4B", self.magic, self._io, u"/seq/0")
        self.ofs_index = self._io.read_u4le()
        self.len_index = self._io.read_u4le()


    def _fetch_instances(self):
        pass
        _ = self.index
        if hasattr(self, '_m_index'):
            pass
            self._m_index._fetch_instances()


    class IndexEntry(KaitaiStruct):
        def __init__(self, _io, _parent=None, _root=None):
            super(QuakePak.IndexEntry, self).__init__(_io)
            self._parent = _parent
            self._root = _root
            self._read()

        def _read(self):
            self.name = (KaitaiStream.bytes_terminate(self._io.read_bytes(56), 0, False)).decode(u"UTF-8")
            self.ofs = self._io.read_u4le()
            self.size = self._io.read_u4le()


        def _fetch_instances(self):
            pass
            _ = self.body
            if hasattr(self, '_m_body'):
                pass


        @property
        def body(self):
            if hasattr(self, '_m_body'):
                return self._m_body

            io = self._root._io
            _pos = io.pos()
            io.seek(self.ofs)
            self._m_body = io.read_bytes(self.size)
            io.seek(_pos)
            return getattr(self, '_m_body', None)


    class IndexStruct(KaitaiStruct):
        def __init__(self, _io, _parent=None, _root=None):
            super(QuakePak.IndexStruct, self).__init__(_io)
            self._parent = _parent
            self._root = _root
            self._read()

        def _read(self):
            self.entries = []
            i = 0
            while not self._io.is_eof():
                self.entries.append(QuakePak.IndexEntry(self._io, self, self._root))
                i += 1



        def _fetch_instances(self):
            pass
            for i in range(len(self.entries)):
                pass
                self.entries[i]._fetch_instances()



    @property
    def index(self):
        if hasattr(self, '_m_index'):
            return self._m_index

        _pos = self._io.pos()
        self._io.seek(self.ofs_index)
        self._raw__m_index = self._io.read_bytes(self.len_index)
        _io__raw__m_index = KaitaiStream(BytesIO(self._raw__m_index))
        self._m_index = QuakePak.IndexStruct(_io__raw__m_index, self, self._root)
        self._io.seek(_pos)
        return getattr(self, '_m_index', None)