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Refactor Compression and Streams, and Add IStream Direct Interface

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This commit is contained in:
LRFLEW
2025-07-04 11:55:17 -05:00
committed by GitHub
parent 31d2092b69
commit 4101fb65a9
24 changed files with 892 additions and 720 deletions
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96
src/openrct2/core/OrcaStream.hpp
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@@ -90,35 +90,46 @@ namespace OpenRCT2
_chunks.push_back(entry);
}
// Read compressed data into buffer (read in blocks)
_buffer = MemoryStream{};
uint8_t temp[2048];
uint64_t bytesLeft = _header.CompressedSize;
do
{
auto readLen = std::min(size_t(bytesLeft), sizeof(temp));
_stream->Read(temp, readLen);
_buffer.Write(temp, readLen);
bytesLeft -= readLen;
} while (bytesLeft > 0);
// Uncompress
if (_header.Compression == CompressionType::gzip)
if (_header.Compression != CompressionType::none)
{
auto uncompressedData = Compression::ungzip(_buffer.GetData(), _buffer.GetLength());
if (_header.UncompressedSize != uncompressedData.size())
size_t compressedSize = static_cast<size_t>(_header.CompressedSize);
size_t uncompressedSize = static_cast<size_t>(_header.UncompressedSize);
bool decompressStatus = false;
switch (_header.Compression)
{
// Warning?
case CompressionType::gzip:
decompressStatus = Compression::zlibDecompress(
*_stream, compressedSize, _buffer, uncompressedSize, Compression::ZlibHeaderType::gzip);
break;
default:
throw IOException("Unknown Park Compression Type");
}
_buffer.Clear();
_buffer.Write(uncompressedData.data(), uncompressedData.size());
if (!decompressStatus)
throw IOException("Decompression Error");
}
else
{
if (_header.UncompressedSize != _header.CompressedSize)
throw IOException("None Compression Sizes Don't Match");
_buffer.CopyFromStream(*_stream, _header.UncompressedSize);
}
// early in-dev versions used SHA1 instead of FNV1a, so just assume any file
// with a verison number of 0 may be one of these, and don't check their hashes.
if (_header.TargetVersion > 0)
{
auto checksum = Crypt::FNV1a(_buffer.GetData(), _buffer.GetLength());
if (checksum != _header.FNV1a)
throw IOException("Checksum Is Not Valid");
}
}
else
{
_header = {};
_header.Compression = CompressionType::gzip;
_buffer = MemoryStream{};
}
}
@@ -129,26 +140,37 @@ namespace OpenRCT2
{
if (_mode == Mode::WRITING)
{
const void* uncompressedData = _buffer.GetData();
const uint64_t uncompressedSize = _buffer.GetLength();
_header.NumChunks = static_cast<uint32_t>(_chunks.size());
_header.UncompressedSize = uncompressedSize;
_header.CompressedSize = uncompressedSize;
_header.FNV1a = Crypt::FNV1a(uncompressedData, uncompressedSize);
_header.UncompressedSize = _buffer.GetLength();
_header.CompressedSize = _buffer.GetLength();
_header.FNV1a = Crypt::FNV1a(_buffer.GetData(), _buffer.GetLength());
// Compress data
std::optional<std::vector<uint8_t>> compressedBytes;
if (_header.Compression == CompressionType::gzip)
if (_header.Compression != CompressionType::none)
{
compressedBytes = Compression::gzip(uncompressedData, uncompressedSize);
if (compressedBytes)
MemoryStream compressed;
size_t bufferLength = static_cast<size_t>(_buffer.GetLength());
bool compressStatus = false;
_buffer.SetPosition(0);
switch (_header.Compression)
{
_header.CompressedSize = compressedBytes->size();
case CompressionType::gzip:
compressStatus = Compression::zlibCompress(
_buffer, bufferLength, compressed, Compression::ZlibHeaderType::gzip);
break;
default:
break;
}
if (compressStatus && compressed.GetLength() < _buffer.GetLength())
{
_buffer = std::move(compressed);
_header.CompressedSize = _buffer.GetLength();
}
else
{
// Compression failed
// Compression increases filesize, so just store uncompressed data
_header.Compression = CompressionType::none;
}
}
@@ -156,19 +178,9 @@ namespace OpenRCT2
// Write header and chunk table
_stream->WriteValue(_header);
for (const auto& chunk : _chunks)
{
_stream->WriteValue(chunk);
}
// Write chunk data
if (compressedBytes)
{
_stream->Write(compressedBytes->data(), compressedBytes->size());
}
else
{
_stream->Write(uncompressedData, uncompressedSize);
}
_stream->Write(_buffer.GetData(), _buffer.GetLength());
}
}