scummvm/engines/teenagent/pack.h
2021-12-26 18:48:43 +01:00

116 lines
3.2 KiB
C++

/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* 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, either version 3 of the License, or
* (at your option) any later version.
*
* 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 for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#ifndef TEENAGENT_PACK_H
#define TEENAGENT_PACK_H
#include "common/file.h"
#include "common/array.h"
namespace TeenAgent {
class Pack {
protected:
uint32 _fileCount;
public:
Pack(): _fileCount(0) {}
virtual ~Pack() {}
virtual bool open(const Common::String &filename) = 0;
virtual void close() = 0;
virtual uint32 fileCount() const { return _fileCount; }
virtual uint32 getSize(uint32 id) const = 0;
virtual uint32 read(uint32 id, byte *dst, uint32 size) const = 0;
virtual Common::SeekableReadStream *getStream(uint32 id) const = 0;
};
///FilePack keeps opened file and returns substream for each request.
class FilePack : public Pack {
mutable Common::File file;
uint32 *offsets;
public:
FilePack();
~FilePack() override;
bool open(const Common::String &filename) override;
void close() override;
uint32 getSize(uint32 id) const override;
uint32 read(uint32 id, byte *dst, uint32 size) const override;
Common::SeekableReadStream *getStream(uint32 id) const override;
};
/** Pack file which reopens file each request. Do not keep file descriptor open.
** Useful for minimizing file descriptors opened at the same time. Critical for PSP backend.
**/
class TransientFilePack : public Pack {
uint32 *offsets;
Common::String _filename;
public:
TransientFilePack();
~TransientFilePack() override;
bool open(const Common::String &filename) override;
void close() override;
uint32 getSize(uint32 id) const override;
uint32 read(uint32 id, byte *dst, uint32 size) const override;
Common::SeekableReadStream *getStream(uint32 id) const override;
};
///MemoryPack loads whole pack in memory, currently unused.
class MemoryPack : public Pack {
struct Chunk {
byte *data;
uint32 size;
inline Chunk(): data(0), size(0) {}
inline Chunk(const Chunk &c) : data(c.data), size(c.size) { c.reset(); }
inline Chunk &operator=(const Chunk &c) {
data = c.data;
size = c.size;
c.reset();
return *this;
}
inline ~Chunk() { delete[] data; }
inline void reset() const {
Chunk *c = const_cast<Chunk *>(this);
c->data = 0;
c->size = 0;
}
};
Common::Array<Chunk> chunks;
public:
bool open(const Common::String &filename) override;
void close() override;
uint32 getSize(uint32 id) const override;
uint32 read(uint32 id, byte *dst, uint32 size) const override;
Common::SeekableReadStream *getStream(uint32 id) const override;
};
} // End of namespace TeenAgent
#endif