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//
// FileStream_WIN32.h
//
// Library: Foundation
// Package: Streams
// Module: FileStream
//
// Definition of the FileStreamBuf, FileInputStream and FileOutputStream classes.
//
// Copyright (c) 2007, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier: BSL-1.0
//
#ifndef Foundation_FileStream_WIN32_INCLUDED
#define Foundation_FileStream_WIN32_INCLUDED
#include "Poco/Foundation.h"
#include "Poco/BufferedBidirectionalStreamBuf.h"
#include "Poco/UnWindows.h"
namespace Poco {
class Foundation_API FileStreamBuf: public BufferedBidirectionalStreamBuf
/// This stream buffer handles Fileio
{
public:
using NativeHandle = HANDLE;
FileStreamBuf();
/// Creates a FileStreamBuf.
~FileStreamBuf();
/// Destroys the FileStream.
void open(const std::string& path, std::ios::openmode mode);
/// Opens the given file in the given mode.
void openHandle(NativeHandle handle, std::ios::openmode mode);
/// Take ownership of the given HANDLE.
bool close();
/// Closes the File stream buffer. Returns true if successful,
/// false otherwise.
bool resizeBuffer(std::streamsize bufferSize) override;
/// Resizes internal buffer. Minimum size is BUFFER_SIZE.
/// Minimum is used when requested size is smaller.
/// Buffer can be resized only when the file is not open.
/// Returns true if resize succeeded.
std::streampos seekoff(std::streamoff off, std::ios::seekdir dir, std::ios::openmode mode = std::ios::in | std::ios::out) override;
/// change position by offset, according to way and mode
std::streampos seekpos(std::streampos pos, std::ios::openmode mode = std::ios::in | std::ios::out) override;
/// change to specified position, according to mode
void flushToDisk();
/// Forces buffered data to be written to the disk
NativeHandle nativeHandle() const;
/// Returns native file descriptor handle
Poco::UInt64 size() const;
/// Returns file size
protected:
enum
{
BUFFER_SIZE = 4096
};
int readFromDevice(char* buffer, std::streamsize length) override;
int writeToDevice(const char* buffer, std::streamsize length) override;
private:
std::string _path;
NativeHandle _handle;
UInt64 _pos {0};
};
} // namespace Poco
#endif // Foundation_FileStream_WIN32_INCLUDED
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