haiku/headers/os/support/DataIO.h
Ingo Weinhold 98759fe6e6 BDataIO: Provide default implementations for Read()/Write()
This makes the interface somewhat more suitable for unidirectional use,
since one doesn't have to implement the other, not needed method.
2014-06-23 22:58:14 +02:00

155 lines
3.7 KiB
C++

/*
* Copyright 2005-2014, Haiku, Inc. All rights reserved.
* Distributed under the terms of the MIT License.
*/
#ifndef _DATA_IO_H
#define _DATA_IO_H
#include <SupportDefs.h>
class BDataIO {
public:
BDataIO();
virtual ~BDataIO();
virtual ssize_t Read(void* buffer, size_t size);
virtual ssize_t Write(const void* buffer, size_t size);
private:
BDataIO(const BDataIO&);
BDataIO& operator=(const BDataIO&);
virtual void _ReservedDataIO1();
virtual void _ReservedDataIO2();
virtual void _ReservedDataIO3();
virtual void _ReservedDataIO4();
virtual void _ReservedDataIO5();
virtual void _ReservedDataIO6();
virtual void _ReservedDataIO7();
virtual void _ReservedDataIO8();
virtual void _ReservedDataIO9();
virtual void _ReservedDataIO10();
virtual void _ReservedDataIO11();
virtual void _ReservedDataIO12();
private:
uint32 _reserved[2];
};
class BPositionIO : public BDataIO {
public:
BPositionIO();
virtual ~BPositionIO();
// BDataIO interface (implemented via ReadAt/WriteAt)
virtual ssize_t Read(void* buffer, size_t size);
virtual ssize_t Write(const void* buffer, size_t size);
// BPositionIO interface
virtual ssize_t ReadAt(off_t position, void* buffer,
size_t size) = 0;
virtual ssize_t WriteAt(off_t position, const void* buffer,
size_t size) = 0;
virtual off_t Seek(off_t position, uint32 seekMode) = 0;
virtual off_t Position() const = 0;
virtual status_t SetSize(off_t size);
virtual status_t GetSize(off_t* size) const;
private:
virtual void _ReservedPositionIO2();
virtual void _ReservedPositionIO3();
virtual void _ReservedPositionIO4();
virtual void _ReservedPositionIO5();
virtual void _ReservedPositionIO6();
virtual void _ReservedPositionIO7();
virtual void _ReservedPositionIO8();
virtual void _ReservedPositionIO9();
virtual void _ReservedPositionIO10();
virtual void _ReservedPositionIO11();
virtual void _ReservedPositionIO12();
private:
uint32 _reserved[2];
};
class BMemoryIO : public BPositionIO {
public:
BMemoryIO(void* data, size_t length);
BMemoryIO(const void* data, size_t length);
virtual ~BMemoryIO();
virtual ssize_t ReadAt(off_t position, void* buffer,
size_t size);
virtual ssize_t WriteAt(off_t position, const void* buffer,
size_t size);
virtual off_t Seek(off_t position, uint32 seekMode);
virtual off_t Position() const;
virtual status_t SetSize(off_t size);
private:
BMemoryIO(const BMemoryIO&);
BMemoryIO& operator=(const BMemoryIO&);
virtual void _ReservedMemoryIO1();
virtual void _ReservedMemoryIO2();
private:
bool fReadOnly;
char* fBuffer;
size_t fLength;
size_t fBufferSize;
size_t fPosition;
uint32 _reserved[1];
};
class BMallocIO : public BPositionIO {
public:
BMallocIO();
virtual ~BMallocIO();
virtual ssize_t ReadAt(off_t position, void* buffer,
size_t size);
virtual ssize_t WriteAt(off_t position, const void* buffer,
size_t size);
virtual off_t Seek(off_t position, uint32 seekMode);
virtual off_t Position() const;
virtual status_t SetSize(off_t size);
// BMallocIO interface
void SetBlockSize(size_t blockSize);
const void* Buffer() const;
size_t BufferLength() const;
private:
BMallocIO(const BMallocIO&);
BMallocIO& operator=(const BMallocIO&);
virtual void _ReservedMallocIO1();
virtual void _ReservedMallocIO2();
private:
size_t fBlockSize;
size_t fMallocSize;
size_t fLength;
char* fData;
off_t fPosition;
uint32 _reserved[1];
};
#endif // _DATA_IO_H