OpenRCT2/src/openrct2/core/MemoryStream.h

72 lines
2.6 KiB
C++

#pragma region Copyright (c) 2014-2017 OpenRCT2 Developers
/*****************************************************************************
* OpenRCT2, an open source clone of Roller Coaster Tycoon 2.
*
* OpenRCT2 is the work of many authors, a full list can be found in contributors.md
* For more information, visit https://github.com/OpenRCT2/OpenRCT2
*
* OpenRCT2 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.
*
* A full copy of the GNU General Public License can be found in licence.txt
*****************************************************************************/
#pragma endregion
#pragma once
#include "../common.h"
#include "IStream.hpp"
namespace MEMORY_ACCESS
{
constexpr uint8 READ = 1 << 0;
constexpr uint8 WRITE = 1 << 1;
constexpr uint8 OWNER = 1 << 2;
};
/**
* A stream for reading and writing to a buffer in memory. By default this buffer can grow.
*/
class MemoryStream final : public IStream
{
private:
uint8 _access = MEMORY_ACCESS::READ | MEMORY_ACCESS::WRITE | MEMORY_ACCESS::OWNER;
size_t _dataCapacity = 0;
size_t _dataSize = 0;
void * _data = nullptr;
void * _position = nullptr;
public:
MemoryStream() = default;
MemoryStream(const MemoryStream & copy);
explicit MemoryStream(size_t capacity);
MemoryStream(void * data, size_t dataSize, uint8 access = MEMORY_ACCESS::READ);
MemoryStream(const void * data, size_t dataSize);
virtual ~MemoryStream();
const void * GetData() const;
void * GetDataCopy() const;
void * TakeData();
///////////////////////////////////////////////////////////////////////////
// ISteam methods
///////////////////////////////////////////////////////////////////////////
bool CanRead() const override;
bool CanWrite() const override;
uint64 GetLength() const override;
uint64 GetPosition() const override;
void SetPosition(uint64 position) override;
void Seek(sint64 offset, sint32 origin) override;
void Read(void * buffer, uint64 length) override;
void Write(const void * buffer, uint64 length) override;
uint64 TryRead(void * buffer, uint64 length) override;
private:
void EnsureCapacity(size_t capacity);
};