private static IReadOnlyList <AssetFileEntry> FillAssetsFilesFromOldFormat(EndianBinaryReader reader, int offset)
{
var fileCount = reader.ReadInt32();
var assetFilesInMemory = new AssetFileEntry[fileCount];
for (var i = 0; i < fileCount; ++i)
{
var fileName = reader.ReadStringToNull();
var fileOffset = reader.ReadInt32();
fileOffset += offset;
var fileSize = reader.ReadInt32();
var originalPosition = reader.Position;
reader.Position = fileOffset;
var buf = new byte[fileSize];
reader.Read(buf, 0, fileSize);
reader.Position = originalPosition;
var memory = new MemoryStream(buf, false);
var memoryFile = new AssetFileEntry(memory, fileName, false);
assetFilesInMemory[i] = memoryFile;
}
return(assetFilesInMemory);
}
private static IReadOnlyList <AssetFileEntry> ReadFormat6(EndianBinaryReader reader, bool padding)
{
var bundleSize = reader.ReadInt64();
var compressedSize = reader.ReadInt32();
var uncompressedSize = reader.ReadInt32();
var flag = reader.ReadInt32();
if (padding)
{
reader.ReadByte();
}
byte[] blocksInfoBytes;
if ((flag & 0x80) == 0)
{
blocksInfoBytes = reader.ReadBytes(compressedSize);
}
else
{
var originalPosition = reader.Position;
reader.Position = reader.BaseStream.Length - compressedSize;
blocksInfoBytes = reader.ReadBytes(compressedSize);
reader.Position = originalPosition;
}
Stream extraStream;
byte[] rawBytes;
switch (flag & 0x3f)
{
case 0:
extraStream = new MemoryStream(blocksInfoBytes, false);
break;
case 1:
rawBytes = SevenZip.Compression.LZMA.SevenZipHelper.Decompress(blocksInfoBytes);
extraStream = new MemoryStream(rawBytes, false);
break;
case 2:
case 3:
rawBytes = new byte[uncompressedSize];
var resultSize = LZ4Codec.Decode(blocksInfoBytes, 0, blocksInfoBytes.Length, rawBytes, 0, uncompressedSize);
extraStream = new MemoryStream(rawBytes, false);
break;
default:
throw new ArgumentOutOfRangeException(nameof(flag), flag, null);
}
AssetFileEntry[] assetFilesInMemory;
using (var blocksInfoReader = new EndianBinaryReader(extraStream, Endian.BigEndian)) {
blocksInfoReader.Position = 0x10;
var blockCount = blocksInfoReader.ReadInt32();
using (var assetsDataStream = new MemoryStream()) {
for (var i = 0; i < blockCount; ++i)
{
uncompressedSize = blocksInfoReader.ReadInt32();
compressedSize = blocksInfoReader.ReadInt32();
flag = blocksInfoReader.ReadInt16();
var compressedBytes = reader.ReadBytes(compressedSize);
byte[] uncompressedBytes;
switch (flag & 0x3f)
{
case 0:
assetsDataStream.Write(compressedBytes, 0, compressedSize);
break;
case 1:
uncompressedBytes = SevenZip.Compression.LZMA.SevenZipHelper.Decompress(compressedBytes);
assetsDataStream.Write(uncompressedBytes, 0, uncompressedSize);
break;
case 2:
case 3:
uncompressedBytes = new byte[uncompressedSize];
var resultSize = LZ4Codec.Decode(compressedBytes, 0, compressedBytes.Length, uncompressedBytes, 0, uncompressedSize);
assetsDataStream.Write(uncompressedBytes, 0, uncompressedSize);
break;
default:
throw new ArgumentOutOfRangeException(nameof(flag), flag, null);
}
}
assetsDataStream.Position = 0;
using (var assetsDataReader = new EndianBinaryReader(assetsDataStream, Endian.BigEndian)) {
var entryCount = blocksInfoReader.ReadInt32();
var temporaryAssetFiles = new List <AssetFileEntry>();
for (var i = 0; i < entryCount; ++i)
{
var entryOffset = blocksInfoReader.ReadInt64();
var entrySize = blocksInfoReader.ReadInt64();
var flags = blocksInfoReader.ReadInt32(); // My guess is: flags=0 => "empty shell"; flags!=0(==4) => real file
var fileName = blocksInfoReader.ReadStringToNull();
assetsDataReader.Position = entryOffset;
var buf = new byte[entrySize];
assetsDataReader.Read(buf, 0, (int)entrySize);
var memory = new MemoryStream(buf, false);
var memoryFile = new AssetFileEntry(memory, fileName, false);
if (flags != 0)
{
temporaryAssetFiles.Add(memoryFile);
}
}
assetFilesInMemory = temporaryAssetFiles.ToArray();
}
}
}
extraStream.Dispose();
return(assetFilesInMemory);
}