mirror of
https://github.com/pocoproject/poco.git
synced 2024-12-13 10:32:57 +01:00
91c256095f
Larger buffers improve performance significantly when streaming large quantity of data on very fast devices.
222 lines
7.1 KiB
C++
222 lines
7.1 KiB
C++
//
|
|
// FileStream.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_INCLUDED
|
|
#define Foundation_FileStream_INCLUDED
|
|
|
|
|
|
#include "Poco/Foundation.h"
|
|
#if defined(POCO_OS_FAMILY_WINDOWS)
|
|
#include "Poco/FileStream_WIN32.h"
|
|
#else
|
|
#include "Poco/FileStream_POSIX.h"
|
|
#endif
|
|
#include <istream>
|
|
#include <ostream>
|
|
|
|
|
|
namespace Poco {
|
|
|
|
|
|
class Foundation_API FileIOS: public virtual std::ios
|
|
/// The base class for FileInputStream and FileOutputStream.
|
|
///
|
|
/// This class is needed to ensure the correct initialization
|
|
/// order of the stream buffer and base classes.
|
|
///
|
|
/// Files are always opened in binary mode, a text mode
|
|
/// with CR-LF translation is not supported. Thus, the
|
|
/// file is always opened as if the std::ios::binary flag
|
|
/// was specified.
|
|
/// Use an InputLineEndingConverter or OutputLineEndingConverter
|
|
/// if you require CR-LF translation.
|
|
///
|
|
/// On Windows platforms, UTF-8 encoded Unicode paths are correctly handled.
|
|
{
|
|
public:
|
|
|
|
using NativeHandle = FileStreamBuf::NativeHandle;
|
|
|
|
FileIOS();
|
|
/// Creates the basic stream.
|
|
|
|
~FileIOS() override;
|
|
/// Destroys the stream.
|
|
|
|
virtual void open(const std::string& path, std::ios::openmode mode);
|
|
/// Opens the file specified by path, using the given mode.
|
|
///
|
|
/// Throws a FileException (or a similar exception) if the file
|
|
/// does not exist or is not accessible for other reasons and
|
|
/// a new file cannot be created.
|
|
|
|
void openHandle(NativeHandle handle, std::ios::openmode mode);
|
|
/// Takes ownership of the handle.
|
|
|
|
void close();
|
|
/// Closes the file stream.
|
|
///
|
|
/// If, for an output stream, the close operation fails (because
|
|
/// the contents of the stream buffer cannot synced back to
|
|
/// the filesystem), the bad bit is set in the stream state.
|
|
|
|
FileStreamBuf* rdbuf();
|
|
/// Returns a pointer to the underlying streambuf.
|
|
|
|
NativeHandle nativeHandle() const;
|
|
/// Returns native file descriptor handle
|
|
|
|
UInt64 size() const;
|
|
/// Returns file size
|
|
|
|
void flushToDisk();
|
|
/// Forces buffered data to be written to the disk
|
|
|
|
protected:
|
|
FileStreamBuf _buf;
|
|
};
|
|
|
|
|
|
class Foundation_API FileInputStream: public FileIOS, public std::istream
|
|
/// An input stream for reading from a file.
|
|
///
|
|
/// Files are always opened in binary mode, a text mode
|
|
/// with CR-LF translation is not supported. Thus, the
|
|
/// file is always opened as if the std::ios::binary flag
|
|
/// was specified.
|
|
/// Use an InputLineEndingConverter if you require CR-LF translation.
|
|
///
|
|
/// On Windows platforms, UTF-8 encoded Unicode paths are correctly handled.
|
|
{
|
|
public:
|
|
FileInputStream();
|
|
/// Creates an unopened FileInputStream.
|
|
|
|
FileInputStream(const std::string& path, std::ios::openmode mode = std::ios::in);
|
|
/// Creates the FileInputStream for the file given by path, using
|
|
/// the given mode.
|
|
///
|
|
/// The std::ios::in flag is always set, regardless of the actual
|
|
/// value specified for mode.
|
|
///
|
|
/// Throws a FileNotFoundException (or a similar exception) if the file
|
|
/// does not exist or is not accessible for other reasons.
|
|
|
|
~FileInputStream() override;
|
|
/// Destroys the stream.
|
|
|
|
void open(const std::string& path, std::ios::openmode mode = std::ios::in) override;
|
|
/// Opens the file specified by path, using the given mode, which
|
|
/// will always include std::ios::in (even if not specified).
|
|
///
|
|
/// Throws a FileException (or a similar exception) if the file
|
|
/// does not exist or is not accessible for other reasons and
|
|
/// a new file cannot be created.
|
|
};
|
|
|
|
|
|
class Foundation_API FileOutputStream: public FileIOS, public std::ostream
|
|
/// An output stream for writing to a file.
|
|
///
|
|
/// Files are always opened in binary mode, a text mode
|
|
/// with CR-LF translation is not supported. Thus, the
|
|
/// file is always opened as if the std::ios::binary flag
|
|
/// was specified.
|
|
/// Use an OutputLineEndingConverter if you require CR-LF translation.
|
|
///
|
|
/// On Windows platforms, UTF-8 encoded Unicode paths are correctly handled.
|
|
{
|
|
public:
|
|
FileOutputStream();
|
|
/// Creats an unopened FileOutputStream.
|
|
|
|
FileOutputStream(const std::string& path, std::ios::openmode mode = std::ios::out | std::ios::trunc);
|
|
/// Creates the FileOutputStream for the file given by path, using
|
|
/// the given mode.
|
|
///
|
|
/// The std::ios::out is always set, regardless of the actual
|
|
/// value specified for mode.
|
|
///
|
|
/// Throws a FileException (or a similar exception) if the file
|
|
/// does not exist or is not accessible for other reasons and
|
|
/// a new file cannot be created.
|
|
///
|
|
/// NOTE: The default mode std::ios::out | std::ios::trunc is different from the default
|
|
/// for std::ofstream, which is std::ios::out only. This is for backwards compatibility
|
|
/// with earlier POCO versions.
|
|
|
|
~FileOutputStream() override;
|
|
/// Destroys the FileOutputStream.
|
|
|
|
void open(const std::string& path, std::ios::openmode mode = std::ios::out | std::ios::trunc) override;
|
|
/// Opens the file specified by path, using the given mode, which
|
|
/// always includes std::ios::out, even if not specified.
|
|
///
|
|
/// Throws a FileException (or a similar exception) if the file
|
|
/// does not exist or is not accessible for other reasons and
|
|
/// a new file cannot be created.
|
|
///
|
|
/// NOTE: The default mode std::ios::out | std::ios::trunc is different from the default
|
|
/// for std::ostream, which is std::ios::out only. This is for backwards compatibility
|
|
/// with earlier POCO versions.
|
|
};
|
|
|
|
|
|
class Foundation_API FileStream: public FileIOS, public std::iostream
|
|
/// A stream for reading from and writing to a file.
|
|
///
|
|
/// Files are always opened in binary mode, a text mode
|
|
/// with CR-LF translation is not supported. Thus, the
|
|
/// file is always opened as if the std::ios::binary flag
|
|
/// was specified.
|
|
/// Use an InputLineEndingConverter or OutputLineEndingConverter
|
|
/// if you require CR-LF translation.
|
|
///
|
|
/// A seek (seekg() or seekp()) operation will always set the
|
|
/// read position and the write position simultaneously to the
|
|
/// same value.
|
|
///
|
|
/// On Windows platforms, UTF-8 encoded Unicode paths are correctly handled.
|
|
{
|
|
public:
|
|
FileStream();
|
|
/// Creats an unopened FileStream.
|
|
|
|
FileStream(const std::string& path, std::ios::openmode mode = std::ios::out | std::ios::in);
|
|
/// Creates the FileStream for the file given by path, using
|
|
/// the given mode.
|
|
///
|
|
/// NOTE: The default mode std::ios::in | std::ios::out is different from the default
|
|
/// for std::fstream, which is std::ios::out only. This is for backwards compatibility
|
|
/// with earlier POCO versions.
|
|
|
|
~FileStream() override;
|
|
/// Destroys the FileOutputStream.
|
|
|
|
void open(const std::string& path, std::ios::openmode mode = std::ios::out | std::ios::in) override;
|
|
/// Opens the file specified by path, using the given mode.
|
|
///
|
|
/// Throws a FileException (or a similar exception) if the file
|
|
/// does not exist or is not accessible for other reasons and
|
|
/// a new file cannot be created.
|
|
};
|
|
|
|
|
|
} // namespace Poco
|
|
|
|
|
|
#endif // Foundation_FileStream_INCLUDED
|