libretro-dolphin/Source/Core/DiscIO/CISOBlob.h
2020-06-21 20:47:23 +02:00

66 lines
1.5 KiB
C++

// Copyright 2008 Dolphin Emulator Project
// Licensed under GPLv2+
// Refer to the license.txt file included.
#pragma once
#include <cstdio>
#include <memory>
#include <string>
#include "Common/CommonTypes.h"
#include "Common/File.h"
#include "DiscIO/Blob.h"
namespace DiscIO
{
static constexpr u32 CISO_MAGIC = 0x4F534943; // "CISO" (byteswapped to little endian)
static const u32 CISO_HEADER_SIZE = 0x8000;
static const u32 CISO_MAP_SIZE = CISO_HEADER_SIZE - sizeof(u32) - sizeof(char) * 4;
struct CISOHeader
{
// "CISO"
u32 magic;
// little endian
u32 block_size;
// 0=unused, 1=used, others=invalid
u8 map[CISO_MAP_SIZE];
};
class CISOFileReader : public BlobReader
{
public:
static std::unique_ptr<CISOFileReader> Create(File::IOFile file);
BlobType GetBlobType() const override { return BlobType::CISO; }
u64 GetRawSize() const override;
// The CISO format does not save the original file size.
// This function returns an upper bound.
u64 GetDataSize() const override;
bool IsDataSizeAccurate() const override { return false; }
u64 GetBlockSize() const override { return m_block_size; }
bool HasFastRandomAccessInBlock() const override { return true; }
std::string GetCompressionMethod() const override { return {}; }
bool Read(u64 offset, u64 nbytes, u8* out_ptr) override;
private:
CISOFileReader(File::IOFile file);
typedef u16 MapType;
static const MapType UNUSED_BLOCK_ID = UINT16_MAX;
File::IOFile m_file;
u64 m_size;
u32 m_block_size;
MapType m_ciso_map[CISO_MAP_SIZE];
};
} // namespace DiscIO