private static void UE4ChunkUnzip(string source, string destination)
{
if (!File.Exists(source))
{
return;
}
using (BinaryReader inReader = new BinaryReader(File.Open(source, FileMode.Open)))
{
using (BinaryWriter binaryWriter = new BinaryWriter(File.Open(destination, FileMode.Create)))
{
FCompressedChunkInfo fcompressedChunkInfo1 = new FCompressedChunkInfo();
fcompressedChunkInfo1.Serialize(inReader);
FCompressedChunkInfo fcompressedChunkInfo2 = new FCompressedChunkInfo();
fcompressedChunkInfo2.Serialize(inReader);
long num1 = fcompressedChunkInfo1.CompressedSize;
long num2 = fcompressedChunkInfo1.UncompressedSize;
if (num2 == 2653586369L)
{
num2 = 131072L;
}
long length = (fcompressedChunkInfo2.UncompressedSize + num2 - 1L) / num2;
FCompressedChunkInfo[] fcompressedChunkInfoArray = new FCompressedChunkInfo[length];
long val2 = 0L;
for (int index = 0; index < length; ++index)
{
fcompressedChunkInfoArray[index] = new FCompressedChunkInfo();
fcompressedChunkInfoArray[index].Serialize(inReader);
val2 = Math.Max(fcompressedChunkInfoArray[index].CompressedSize, val2);
}
for (long index = 0L; index < length; ++index)
{
FCompressedChunkInfo fcompressedChunkInfo3 = fcompressedChunkInfoArray[index];
byte[] buffer = ZlibStream.UncompressBuffer(inReader.ReadBytes((int)fcompressedChunkInfo3.CompressedSize));
binaryWriter.Write(buffer);
}
}
}
}
protected byte[] LoadCompressedChunk(BinaryReader reader)
{
try
{
FCompressedChunkInfo PackageFileTag = new FCompressedChunkInfo();
PackageFileTag.CompressedSize = reader.ReadInt64();
PackageFileTag.UncompressedSize = reader.ReadInt64();
FCompressedChunkInfo Summary = new FCompressedChunkInfo();
Summary.CompressedSize = reader.ReadInt64();
Summary.UncompressedSize = reader.ReadInt64();
bool bWasByteSwapped = PackageFileTag.CompressedSize != PACKAGE_FILE_TAG;
bool bHeaderWasValid = true;
if (bWasByteSwapped)
{
bHeaderWasValid = PackageFileTag.CompressedSize == PACKAGE_FILE_TAG_SWAPPED;
if (bHeaderWasValid)
{
// not supported
//Summary.CompressedSize = BYTESWAP_ORDER64(Summary.CompressedSize);
//Summary.UncompressedSize = BYTESWAP_ORDER64(Summary.UncompressedSize);
//PackageFileTag.UncompressedSize = BYTESWAP_ORDER64(PackageFileTag.UncompressedSize);
}
}
else
{
bHeaderWasValid = PackageFileTag.CompressedSize == PACKAGE_FILE_TAG;
}
// Handle change in compression chunk size in backward compatible way.
long LoadingCompressionChunkSize = PackageFileTag.UncompressedSize;
if (LoadingCompressionChunkSize == PACKAGE_FILE_TAG)
{
LoadingCompressionChunkSize = LOADING_COMPRESSION_CHUNK_SIZE;
}
// Figure out how many chunks there are going to be based on uncompressed size and compression chunk size.
long TotalChunkCount = (Summary.UncompressedSize + LoadingCompressionChunkSize - 1) / LoadingCompressionChunkSize;
// Allocate compression chunk infos and serialize them, keeping track of max size of compression chunks used.
FCompressedChunkInfo[] CompressionChunks = new FCompressedChunkInfo[TotalChunkCount];
long MaxCompressedSize = 0;
for (int ChunkIndex = 0; ChunkIndex < TotalChunkCount; ChunkIndex++)
{
CompressionChunks[ChunkIndex].CompressedSize = reader.ReadInt64();
CompressionChunks[ChunkIndex].UncompressedSize = reader.ReadInt64();
if (bWasByteSwapped)
{
// not supported
//CompressionChunks[ChunkIndex].CompressedSize = BYTESWAP_ORDER64(CompressionChunks[ChunkIndex].CompressedSize);
//CompressionChunks[ChunkIndex].UncompressedSize = BYTESWAP_ORDER64(CompressionChunks[ChunkIndex].UncompressedSize);
}
MaxCompressedSize = Math.Max(CompressionChunks[ChunkIndex].CompressedSize, MaxCompressedSize);
}
byte[] DeCompressedBuffer = new byte[Summary.UncompressedSize];
int offset = 0;
// Iterate over all chunks, serialize them into memory and decompress them directly into the destination pointer
for (long ChunkIndex = 0; ChunkIndex < TotalChunkCount; ChunkIndex++)
{
// Read compressed data.
byte[] initialSkip = reader.ReadBytes(2);
byte[] CompressedBuffer = reader.ReadBytes((int)CompressionChunks[ChunkIndex].CompressedSize - 6);
byte[] finalSkip = reader.ReadBytes(4);
MemoryStream ms = new MemoryStream(CompressedBuffer);
DeflateStream gzip = new DeflateStream(ms, CompressionMode.Decompress);
gzip.Read(DeCompressedBuffer, offset, (int)CompressionChunks[ChunkIndex].UncompressedSize);
// Decompress into dest pointer directly.
offset += (int)CompressionChunks[ChunkIndex].UncompressedSize;
}
return(DeCompressedBuffer);
}
catch
{
return(null);
}
}
