dolphin/Source/Core/DiscIO/Src/Blob.h

// Copyright (C) 2003-2008 Dolphin Project.

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, version 2.0.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License 2.0 for more details.

// A copy of the GPL 2.0 should have been included with the program.
// If not, see http://www.gnu.org/licenses/

// Official SVN repository and contact information can be found at
// http://code.google.com/p/dolphin-emu/

#ifndef _BLOB_H
#define _BLOB_H

// BLOB

// Blobs in Dolphin are read only Binary Large OBjects. For example, a typical DVD image.
// Often, you may want to store these things in a highly compressed format, but still
// allow random access. Or you may store them on an odd device, like raw on a DVD.

// Always read your BLOBs using an interface returned by CreateBlobReader(). It will
// detect whether the file is a compressed blob, or just a big hunk of data, and
// automatically do the right thing.

#include "Common.h"

namespace DiscIO
{

class IBlobReader
{
public:
	virtual ~IBlobReader() {}

	virtual u64 GetRawSize() const  = 0;
	virtual u64 GetDataSize() const = 0;
	virtual bool Read(u64 offset, u64 size, u8* out_ptr) = 0;

protected:
	IBlobReader() {}
};


// Provides caching and split-operation-to-block-operations facilities.
// Used for compressed blob reading and direct drive reading.
class SectorReader : public IBlobReader
{
private:
	virtual void GetBlock(u64 block_num, u8 *out) = 0;
	enum { CACHE_SIZE = 32 };
	int m_blocksize;
	u8* cache[CACHE_SIZE];
	u64 cache_tags[CACHE_SIZE];
	int cache_age[CACHE_SIZE];
protected:
	void SetSectorSize(int blocksize);
public:
	~SectorReader();
	const u8 *GetBlockData(u64 block_num);
	bool Read(u64 offset, u64 size, u8* out_ptr);
};

// Factory function - examines the path to choose the right type of IBlobReader, and returns one.
IBlobReader* CreateBlobReader(const char* filename);

typedef void (*CompressCB)(const char* text, float percent, void* arg);

bool CompressFileToBlob(const char* infile, const char* outfile, u32 sub_type = 0, int sector_size = 16384,
		CompressCB callback = 0, void* arg = 0);
bool DecompressBlobToFile(const char* infile, const char* outfile,
		CompressCB callback = 0, void* arg = 0);

}  // namespace

#endif