dolphin/Source/Core/DiscIO/CompressedBlob.h
JosJuice a87dffe52d DiscIO: Replace IsDataSizeAccurate with GetDataSizeType
Previously, we had WBFS and CISO which both returned an upper bound
of the size, and other formats which returned an accurate size. But
now we also have NFS, which returns a lower bound of the size. To
allow VolumeVerifier to make better informed decisions for NFS, let's
use an enum instead of a bool for the type of data size a blob has.
2022-08-04 22:00:59 +02:00

80 lines
2.2 KiB
C++

// Copyright 2008 Dolphin Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later
// WARNING Code not big-endian safe.
// To create new compressed BLOBs, use CompressFileToBlob.
// File format
// * Header
// * [Block Pointers interleaved with block hashes (hash of decompressed data)]
// * [Data]
#pragma once
#include <memory>
#include <string>
#include <vector>
#include "Common/CommonTypes.h"
#include "Common/IOFile.h"
#include "DiscIO/Blob.h"
namespace DiscIO
{
static constexpr u32 GCZ_MAGIC = 0xB10BC001;
// GCZ file structure:
// BlobHeader
// u64 offsetsToBlocks[n], top bit specifies whether the block is compressed, or not.
// compressed data
// Blocks that won't compress to less than 97% of the original size are stored as-is.
struct CompressedBlobHeader // 32 bytes
{
u32 magic_cookie; // 0xB10BB10B
u32 sub_type; // GC image, whatever
u64 compressed_data_size;
u64 data_size;
u32 block_size;
u32 num_blocks;
};
class CompressedBlobReader : public SectorReader
{
public:
static std::unique_ptr<CompressedBlobReader> Create(File::IOFile file,
const std::string& filename);
~CompressedBlobReader();
const CompressedBlobHeader& GetHeader() const { return m_header; }
BlobType GetBlobType() const override { return BlobType::GCZ; }
u64 GetRawSize() const override { return m_file_size; }
u64 GetDataSize() const override { return m_header.data_size; }
DataSizeType GetDataSizeType() const override { return DataSizeType::Accurate; }
u64 GetBlockSize() const override { return m_header.block_size; }
bool HasFastRandomAccessInBlock() const override { return false; }
std::string GetCompressionMethod() const override { return "Deflate"; }
std::optional<int> GetCompressionLevel() const override { return std::nullopt; }
u64 GetBlockCompressedSize(u64 block_num) const;
bool GetBlock(u64 block_num, u8* out_ptr) override;
private:
CompressedBlobReader(File::IOFile file, const std::string& filename);
CompressedBlobHeader m_header;
std::vector<u64> m_block_pointers;
std::vector<u32> m_hashes;
int m_data_offset;
File::IOFile m_file;
u64 m_file_size;
std::vector<u8> m_zlib_buffer;
std::string m_file_name;
};
} // namespace DiscIO