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

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//
// BinaryWriter.h
//
// $Id: //poco/1.4/Foundation/include/Poco/BinaryWriter.h#2 $
//
// Library: Foundation
// Package: Streams
// Module: BinaryReaderWriter
//
// Definition of the BinaryWriter class.
//
// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier: BSL-1.0
//
#ifndef Foundation_BinaryWriter_INCLUDED
#define Foundation_BinaryWriter_INCLUDED
#include "Poco/Foundation.h"
#include "Poco/Buffer.h"
#include "Poco/MemoryStream.h"
#include <vector>
#include <ostream>
namespace Poco {
class TextEncoding;
class TextConverter;
class Foundation_API BinaryWriter
/// This class writes basic types (and std::vectors of these)
/// in binary form into an output stream.
/// It provides an inserter-based interface similar to ostream.
/// The writer also supports automatic conversion from big-endian
/// (network byte order) to little-endian and vice-versa.
/// Use a BinaryReader to read from a stream created by a BinaryWriter.
/// Be careful when exchanging data between systems with different
/// data type sizes (e.g., 32-bit and 64-bit architectures), as the sizes
/// of some of the basic types may be different. For example, writing a
/// long integer on a 64-bit system and reading it on a 32-bit system
/// may yield an incorrent result. Use fixed-size types (Int32, Int64, etc.)
/// in such a case.
{
public:
enum StreamByteOrder
{
NATIVE_BYTE_ORDER = 1, /// the host's native byte-order
BIG_ENDIAN_BYTE_ORDER = 2, /// big-endian (network) byte-order
NETWORK_BYTE_ORDER = 2, /// big-endian (network) byte-order
LITTLE_ENDIAN_BYTE_ORDER = 3 /// little-endian byte-order
};
BinaryWriter(std::ostream& ostr, StreamByteOrder byteOrder = NATIVE_BYTE_ORDER);
/// Creates the BinaryWriter.
BinaryWriter(std::ostream& ostr, TextEncoding& encoding, StreamByteOrder byteOrder = NATIVE_BYTE_ORDER);
/// Creates the BinaryWriter using the given TextEncoding.
///
/// Strings will be converted from the currently set global encoding
/// (see Poco::TextEncoding::global()) to the specified encoding.
~BinaryWriter();
/// Destroys the BinaryWriter.
BinaryWriter& operator << (bool value);
BinaryWriter& operator << (char value);
BinaryWriter& operator << (unsigned char value);
BinaryWriter& operator << (signed char value);
BinaryWriter& operator << (short value);
BinaryWriter& operator << (unsigned short value);
BinaryWriter& operator << (int value);
BinaryWriter& operator << (unsigned int value);
BinaryWriter& operator << (long value);
BinaryWriter& operator << (unsigned long value);
BinaryWriter& operator << (float value);
BinaryWriter& operator << (double value);
#if defined(POCO_HAVE_INT64) && !defined(POCO_LONG_IS_64_BIT)
BinaryWriter& operator << (Int64 value);
BinaryWriter& operator << (UInt64 value);
#endif
BinaryWriter& operator << (const std::string& value);
BinaryWriter& operator << (const char* value);
template <typename T>
BinaryWriter& operator << (const std::vector<T>& value)
{
Poco::UInt32 size(static_cast<Poco::UInt32>(value.size()));
*this << size;
for (typename std::vector<T>::const_iterator it = value.begin(); it != value.end(); ++it)
{
*this << *it;
}
return *this;
}
void write7BitEncoded(UInt32 value);
/// Writes a 32-bit unsigned integer in a compressed format.
/// The value is written out seven bits at a time, starting
/// with the seven least-significant bits.
/// The high bit of a byte indicates whether there are more bytes to be
/// written after this one.
/// If value will fit in seven bits, it takes only one byte of space.
/// If value will not fit in seven bits, the high bit is set on the first byte and
/// written out. value is then shifted by seven bits and the next byte is written.
/// This process is repeated until the entire integer has been written.
#if defined(POCO_HAVE_INT64)
void write7BitEncoded(UInt64 value);
/// Writes a 64-bit unsigned integer in a compressed format.
/// The value written out seven bits at a time, starting
/// with the seven least-significant bits.
/// The high bit of a byte indicates whether there are more bytes to be
/// written after this one.
/// If value will fit in seven bits, it takes only one byte of space.
/// If value will not fit in seven bits, the high bit is set on the first byte and
/// written out. value is then shifted by seven bits and the next byte is written.
/// This process is repeated until the entire integer has been written.
#endif
void writeRaw(const std::string& rawData);
/// Writes the string as-is to the stream.
void writeRaw(const char* buffer, std::streamsize length);
/// Writes length raw bytes from the given buffer to the stream.
void writeBOM();
/// Writes a byte-order mark to the stream. A byte order mark is
/// a 16-bit integer with a value of 0xFEFF, written in host byte-order.
/// A BinaryReader uses the byte-order mark to determine the byte-order
/// of the stream.
void flush();
/// Flushes the underlying stream.
bool good();
/// Returns _ostr.good();
bool fail();
/// Returns _ostr.fail();
bool bad();
/// Returns _ostr.bad();
std::ostream& stream() const;
/// Returns the underlying stream.
StreamByteOrder byteOrder() const;
/// Returns the byte ordering used by the writer, which is
/// either BIG_ENDIAN_BYTE_ORDER or LITTLE_ENDIAN_BYTE_ORDER.
private:
std::ostream& _ostr;
bool _flipBytes;
TextConverter* _pTextConverter;
};
template <typename T>
class BasicMemoryBinaryWriter: public BinaryWriter
/// A convenient wrapper for using Buffer and MemoryStream with BinarWriter.
{
public:
BasicMemoryBinaryWriter(Buffer<T>& data, StreamByteOrder byteOrder = NATIVE_BYTE_ORDER):
BinaryWriter(_ostr, byteOrder),
_data(data),
_ostr(data.begin(), data.capacity())
{
}
BasicMemoryBinaryWriter(Buffer<T>& data, TextEncoding& encoding, StreamByteOrder byteOrder = NATIVE_BYTE_ORDER):
BinaryWriter(_ostr, encoding, byteOrder),
_data(data),
_ostr(data.begin(), data.capacity())
{
}
~BasicMemoryBinaryWriter()
{
try
{
flush();
}
catch (...)
{
poco_unexpected();
}
}
Buffer<T>& data()
{
return _data;
}
const Buffer<T>& data() const
{
return _data;
}
const MemoryOutputStream& stream() const
{
return _ostr;
}
MemoryOutputStream& stream()
{
return _ostr;
}
private:
Buffer<T>& _data;
MemoryOutputStream _ostr;
};
typedef BasicMemoryBinaryWriter<char> MemoryBinaryWriter;
//
// inlines
//
inline std::ostream& BinaryWriter::stream() const
{
return _ostr;
}
inline bool BinaryWriter::good()
{
return _ostr.good();
}
inline bool BinaryWriter::fail()
{
return _ostr.fail();
}
inline bool BinaryWriter::bad()
{
return _ostr.bad();
}
inline BinaryWriter::StreamByteOrder BinaryWriter::byteOrder() const
{
#if defined(POCO_ARCH_BIG_ENDIAN)
return _flipBytes ? LITTLE_ENDIAN_BYTE_ORDER : BIG_ENDIAN_BYTE_ORDER;
#else
return _flipBytes ? BIG_ENDIAN_BYTE_ORDER : LITTLE_ENDIAN_BYTE_ORDER;
#endif
}
} // namespace Poco
#endif // Foundation_BinaryWriter_INCLUDED