mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-11-19 22:22:00 +00:00
93 lines
1.8 KiB
C++
93 lines
1.8 KiB
C++
//
|
|
// NullStream.h
|
|
//
|
|
// $Id: //poco/1.4/Foundation/include/Poco/NullStream.h#1 $
|
|
//
|
|
// Library: Foundation
|
|
// Package: Streams
|
|
// Module: NullStream
|
|
//
|
|
// Definition of the NullStreamBuf, NullInputStream and NullOutputStream classes.
|
|
//
|
|
// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
|
|
// and Contributors.
|
|
//
|
|
// SPDX-License-Identifier: BSL-1.0
|
|
//
|
|
|
|
|
|
#ifndef Foundation_NullStream_INCLUDED
|
|
#define Foundation_NullStream_INCLUDED
|
|
|
|
|
|
#include "Poco/Foundation.h"
|
|
#include "Poco/UnbufferedStreamBuf.h"
|
|
#include <istream>
|
|
#include <ostream>
|
|
|
|
|
|
namespace Poco {
|
|
|
|
|
|
class Foundation_API NullStreamBuf: public UnbufferedStreamBuf
|
|
/// This stream buffer discards all characters written to it.
|
|
/// Any read operation immediately yields EOF.
|
|
{
|
|
public:
|
|
NullStreamBuf();
|
|
/// Creates a NullStreamBuf.
|
|
|
|
~NullStreamBuf();
|
|
/// Destroys the NullStreamBuf.
|
|
|
|
protected:
|
|
int readFromDevice();
|
|
int writeToDevice(char c);
|
|
};
|
|
|
|
|
|
class Foundation_API NullIOS: public virtual std::ios
|
|
/// The base class for NullInputStream and NullOutputStream.
|
|
///
|
|
/// This class is needed to ensure the correct initialization
|
|
/// order of the stream buffer and base classes.
|
|
{
|
|
public:
|
|
NullIOS();
|
|
~NullIOS();
|
|
|
|
protected:
|
|
NullStreamBuf _buf;
|
|
};
|
|
|
|
|
|
class Foundation_API NullInputStream: public NullIOS, public std::istream
|
|
/// Any read operation from this stream immediately
|
|
/// yields EOF.
|
|
{
|
|
public:
|
|
NullInputStream();
|
|
/// Creates the NullInputStream.
|
|
|
|
~NullInputStream();
|
|
/// Destroys the NullInputStream.
|
|
};
|
|
|
|
|
|
class Foundation_API NullOutputStream: public NullIOS, public std::ostream
|
|
/// This stream discards all characters written to it.
|
|
{
|
|
public:
|
|
NullOutputStream();
|
|
/// Creates the NullOutputStream.
|
|
|
|
~NullOutputStream();
|
|
/// Destroys the NullOutputStream.
|
|
};
|
|
|
|
|
|
} // namespace Poco
|
|
|
|
|
|
#endif // Foundation_NullStream_INCLUDED
|