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

Application

Quake game engine

File extension

pak

KS implementation details

License: CC0-1.0

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 Java generated by Kaitai Struct depends on the Java runtime library. You have to install it before you can parse data.

The Java runtime library is published in the Maven Central Repository. Refer to the artifact page for instructions how to add it into your project with the build tool that you use.

Code

Parse a local file and get structure in memory:

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

Or parse structure from a byte array:

byte[] someArray = new byte[] { ... };
QuakePak data = new QuakePak(new ByteBufferKaitaiStream(someArray));

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

data.magic() // => get magic

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

QuakePak.java

// This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild

import io.kaitai.struct.ByteBufferKaitaiStream;
import io.kaitai.struct.KaitaiStruct;
import io.kaitai.struct.KaitaiStream;
import java.io.IOException;
import java.util.Arrays;
import java.util.ArrayList;
import java.nio.charset.Charset;


/**
 * @see <a href="https://quakewiki.org/wiki/.pak#Format_specification">Source</a>
 */
public class QuakePak extends KaitaiStruct {
    public static QuakePak fromFile(String fileName) throws IOException {
        return new QuakePak(new ByteBufferKaitaiStream(fileName));
    }

    public QuakePak(KaitaiStream _io) {
        this(_io, null, null);
    }

    public QuakePak(KaitaiStream _io, KaitaiStruct _parent) {
        this(_io, _parent, null);
    }

    public QuakePak(KaitaiStream _io, KaitaiStruct _parent, QuakePak _root) {
        super(_io);
        this._parent = _parent;
        this._root = _root == null ? this : _root;
        _read();
    }
    private void _read() {
        this.magic = this._io.readBytes(4);
        if (!(Arrays.equals(magic(), new byte[] { 80, 65, 67, 75 }))) {
            throw new KaitaiStream.ValidationNotEqualError(new byte[] { 80, 65, 67, 75 }, magic(), _io(), "/seq/0");
        }
        this.ofsIndex = this._io.readU4le();
        this.lenIndex = this._io.readU4le();
    }
    public static class IndexStruct extends KaitaiStruct {
        public static IndexStruct fromFile(String fileName) throws IOException {
            return new IndexStruct(new ByteBufferKaitaiStream(fileName));
        }

        public IndexStruct(KaitaiStream _io) {
            this(_io, null, null);
        }

        public IndexStruct(KaitaiStream _io, QuakePak _parent) {
            this(_io, _parent, null);
        }

        public IndexStruct(KaitaiStream _io, QuakePak _parent, QuakePak _root) {
            super(_io);
            this._parent = _parent;
            this._root = _root;
            _read();
        }
        private void _read() {
            this.entries = new ArrayList<IndexEntry>();
            {
                int i = 0;
                while (!this._io.isEof()) {
                    this.entries.add(new IndexEntry(this._io, this, _root));
                    i++;
                }
            }
        }
        private ArrayList<IndexEntry> entries;
        private QuakePak _root;
        private QuakePak _parent;
        public ArrayList<IndexEntry> entries() { return entries; }
        public QuakePak _root() { return _root; }
        public QuakePak _parent() { return _parent; }
    }
    public static class IndexEntry extends KaitaiStruct {
        public static IndexEntry fromFile(String fileName) throws IOException {
            return new IndexEntry(new ByteBufferKaitaiStream(fileName));
        }

        public IndexEntry(KaitaiStream _io) {
            this(_io, null, null);
        }

        public IndexEntry(KaitaiStream _io, QuakePak.IndexStruct _parent) {
            this(_io, _parent, null);
        }

        public IndexEntry(KaitaiStream _io, QuakePak.IndexStruct _parent, QuakePak _root) {
            super(_io);
            this._parent = _parent;
            this._root = _root;
            _read();
        }
        private void _read() {
            this.name = new String(KaitaiStream.bytesTerminate(KaitaiStream.bytesStripRight(this._io.readBytes(56), (byte) 0), (byte) 0, false), Charset.forName("UTF-8"));
            this.ofs = this._io.readU4le();
            this.size = this._io.readU4le();
        }
        private byte[] body;
        public byte[] body() {
            if (this.body != null)
                return this.body;
            KaitaiStream io = _root._io();
            long _pos = io.pos();
            io.seek(ofs());
            this.body = io.readBytes(size());
            io.seek(_pos);
            return this.body;
        }
        private String name;
        private long ofs;
        private long size;
        private QuakePak _root;
        private QuakePak.IndexStruct _parent;
        public String name() { return name; }
        public long ofs() { return ofs; }
        public long size() { return size; }
        public QuakePak _root() { return _root; }
        public QuakePak.IndexStruct _parent() { return _parent; }
    }
    private IndexStruct index;
    public IndexStruct index() {
        if (this.index != null)
            return this.index;
        long _pos = this._io.pos();
        this._io.seek(ofsIndex());
        this._raw_index = this._io.readBytes(lenIndex());
        KaitaiStream _io__raw_index = new ByteBufferKaitaiStream(_raw_index);
        this.index = new IndexStruct(_io__raw_index, this, _root);
        this._io.seek(_pos);
        return this.index;
    }
    private byte[] magic;
    private long ofsIndex;
    private long lenIndex;
    private QuakePak _root;
    private KaitaiStruct _parent;
    private byte[] _raw_index;
    public byte[] magic() { return magic; }
    public long ofsIndex() { return ofsIndex; }
    public long lenIndex() { return lenIndex; }
    public QuakePak _root() { return _root; }
    public KaitaiStruct _parent() { return _parent; }
    public byte[] _raw_index() { return _raw_index; }
}