ClickHouse/contrib/libpoco/Foundation/include/Poco/RandomStream.h

76 lines
1.5 KiB
C++
Raw Normal View History

//
// RandomStream.h
//
// $Id: //poco/1.4/Foundation/include/Poco/RandomStream.h#1 $
//
// Library: Foundation
// Package: Crypt
// Module: RandomStream
//
// Definition of class RandomInputStream.
//
// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier: BSL-1.0
//
#ifndef Foundation_RandomStream_INCLUDED
#define Foundation_RandomStream_INCLUDED
#include "Poco/Foundation.h"
#include "Poco/BufferedStreamBuf.h"
#include <istream>
namespace Poco {
class Foundation_API RandomBuf: public BufferedStreamBuf
/// This streambuf generates random data.
/// On Windows NT, the cryptographic API is used.
/// On Unix, /dev/random is used, if available.
/// Otherwise, a random number generator, some
/// more-or-less random data and a SHA-1 digest
/// is used to generate random data.
{
public:
RandomBuf();
~RandomBuf();
int readFromDevice(char* buffer, std::streamsize length);
};
class Foundation_API RandomIOS: public virtual std::ios
/// The base class for RandomInputStream.
///
/// This class is needed to ensure the correct initialization
/// order of the stream buffer and base classes.
{
public:
RandomIOS();
~RandomIOS();
RandomBuf* rdbuf();
protected:
RandomBuf _buf;
};
class Foundation_API RandomInputStream: public RandomIOS, public std::istream
/// This istream generates random data
/// using the RandomBuf.
{
public:
RandomInputStream();
~RandomInputStream();
};
} // namespace Poco
#endif // Foundation_RandomStream_INCLUDED