dark

The Internal File Format of the Workshop TempArchiveXX Files

admin
2021-07-15 07:09:32

Basic Structure Of The File

A header containing the number of files

# Bytes Type Meaning 4 int32 Number of files in this archive

Then one block per file:

# Bytes Type Meaning (variable) FString Relative path of File (1-5) FCompactIndex Byte length of File (count) byte File contents

An FString is a null terminated ANSI string stored as follows:

# Bytes Type Meaning (1-5) FCompactIndex Byte length of the string (including null terminator byte) (count) byte String characters each byte appears to be an ANSI code point.

An FCompactIndex is an int32 that is stored in a bit stuffed format.

I found a reference of how to decode an FCompactIndex here:

Packages (snipers paradise)[www.snipersparadise.net]

and here:

Package File Format (beyondunreal wiki)[wiki.beyondunreal.com]

Byte 0 1 2 3 4 Range Bit 76543210 76543210 76543210 76543210 76543210 6 bit s0xxxxxx 13 bit s1xxxxxx 0xxxxxxx 20 bit s1xxxxxx 1xxxxxxx 0xxxxxxx 27 bit s1xxxxxx 1xxxxxxx 1xxxxxxx 0xxxxxxx 32 bit s1xxxxxx 1xxxxxxx 1xxxxxxx 1xxxxxxx 000xxxxx bits 5 - 0 12 - 6 19 - 13 26 - 20 31 - 27

Sample C# Source Code For Extraction Program

In Visual Studio create a Solution for a Windows Console Application.

Add the following two classes to the Project:

Program.cs

using System; using System.IO; using System.Text; namespace TempArchiveExtractor { class Program { static void Main(String[] args) { if (0 == args.Length || String.IsNullOrWhiteSpace(args[0])) { Console.Out.WriteLine("Usage: TempArchiveExtractor [TempArchiveFile]"); return; } FileInfo archiveFile = new FileInfo(args[0]); if (!archiveFile.Exists) { Console.Out.WriteLine("No such file"); return; } FileStream archiveStream = null; try { archiveStream = archiveFile.OpenRead(); TempArchiveReader reader = new TempArchiveReader(archiveStream); Int32 fileCount = reader.ReadInt32(); Console.Out.WriteLine("Archive contains " + fileCount + " files"); for (int i=0; i< fileCount; i++) { String filePath = reader.ReadFString(); Int32 fileLen = reader.ReadFCompactIndex(); FileInfo fi = new FileInfo(filePath); String msg = String.Format("{0} {1} Size: 0x{2:X} {2:N0} [Y/N] : " , fi.Exists ? "Overwrite" : "Extract " , filePath, fileLen); Console.Out.Write(msg); String resp = Console.In.ReadLine(); if ("Y".Equals(resp.ToUpper())) { DirectoryInfo di = fi.Directory; if (!di.Exists) di.Create(); using (FileStream fs = fi.OpenWrite()) { reader.ReadIntoStream(fileLen, fs); } } else { reader.Skip(fileLen); } } } catch (Exception ex) { Console.Out.WriteLine("Error reading archive"); Console.Out.WriteLine(ex); } finally { if (null != archiveStream) archiveStream.Close(); } } } }

TempArchiveReader.cs

using System; using System.IO; using System.Text; namespace TempArchiveExtractor { public class TempArchiveReader { static Encoding ANSIEncoding = Encoding.GetEncoding(1252); public TempArchiveReader(FileStream archiveStream) { _archiveStream = archiveStream; } FileStream _archiveStream; public Int32 ReadInt32() { Int32 result = _archiveStream.ReadByte(); result += _archiveStream.ReadByte() << 8; result += _archiveStream.ReadByte() << 16; result += _archiveStream.ReadByte() << 32; return result; } public Int32 ReadFCompactIndex() { Int32 result = 0; int B0 = _archiveStream.ReadByte(); //String msg = String.Format("FCompactIndex: 0x{0:X}", B0); if ((B0 & 0x40) != 0) { int B1 = _archiveStream.ReadByte(); //msg += String.Format("{0:X}", B1); if ((B1 & 0x80) != 0) { int B2 = _archiveStream.ReadByte(); //msg += String.Format("{0:X}", B2); if ((B2 & 0x80) != 0) { int B3 = _archiveStream.ReadByte(); //msg += String.Format("{0:X}", B3); if ((B3 & 0x80) != 0) { int B4 = _archiveStream.ReadByte(); //msg += String.Format("{0:X}", B4); result = B4; } result = (result << 7) + (B3 & 0x7F); } result = (result << 7) + (B2 & 0x7F); } result = (result << 7) + (B1 & 0x7F); } result = (result << 6) + (B0 & 0x3F); if ((B0 & 0x80) != 0) result *= -1; //msg += String.Format(" => 0x{0:X} {0}", result); //Console.Out.WriteLine(msg); return result; } public String ReadFString() { Int32 strLen = ReadFCompactIndex(); Byte[] strBytes = new Byte[strLen]; _archiveStream.Read(strBytes, 0, strLen); //String msg = String.Format("FString: length 0x{0:X} {0} : {1:X}..{2:X}" // , strLen, strBytes[0], strBytes[strLen-1]); //Console.Out.WriteLine(msg); String str = ANSIEncoding.GetString(strBytes, 0, strLen-1); return str; } public void Skip(Int32 count) { _archiveStream.Seek(count, SeekOrigin.Current); } const int BLOCKSIZE = 0x10000; public void ReadIntoStream(Int32 count, Stream outStream) { Byte[] buffer = new Byte[BLOCKSIZE]; while (count > BLOCKSIZE) { _archiveStream.Read(buffer, 0, BLOCKSIZE); outStream.Write(buffer, 0, BLOCKSIZE); count -= BLOCKSIZE; } _archiveStream.Read(buffer, 0, count); outStream.Write(buffer, 0, count); } } }

Source: https://steamcommunity.com/sharedfiles/filedetails/?id=291724762

More Killing Floor guilds

⮙