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/*
* libnbt++ - A library for the Minecraft Named Binary Tag format.
* Copyright (C) 2013, 2015 ljfa-ag
*
* This file is part of libnbt++.
*
* libnbt++ is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* libnbt++ is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with libnbt++. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef OZLIBSTREAM_H_INCLUDED
#define OZLIBSTREAM_H_INCLUDED
#include <ostream>
#include <vector>
#include <zlib.h>
namespace zlib
{
/**
* @brief Stream buffer used by zlib::ozlibstream
* @sa ozlibstream
*/
class deflate_streambuf : public std::streambuf
{
public:
/**
* @param output the ostream to wrap
* @param bufsize the size of the internal buffers
* @param level the compression level, ranges from 0 to 9
*
* Refer to the zlib documentation of deflateInit2 for details about the arguments.
*
* @throw zlib_error if zlib encounters a problem during initialization
*/
explicit deflate_streambuf(std::ostream& output, size_t bufsize = 32768, int level = Z_DEFAULT_COMPRESSION, int window_bits = 15, int mem_level = 8, int strategy = Z_DEFAULT_STRATEGY);
~deflate_streambuf() noexcept;
std::ostream& get_ostr() const { return os; }
///Finishes compression and writes all pending data to the output
void close();
private:
std::ostream& os;
std::vector<char> in;
std::vector<char> out;
z_stream zstr;
void deflate_chunk(int flush = Z_NO_FLUSH);
int_type overflow(int_type ch) override;
int sync() override;
};
/**
* @brief An ostream adapter that compresses data using zlib
*
* This ostream wraps another ostream. Data written to an ozlibstream will be
* deflated (compressed) with zlib and written to the wrapped ostream.
*
* @sa deflate_streambuf
*/
class ozlibstream : public std::ostream
{
public:
/**
* @param output the ostream to wrap
* @param level the compression level, ranges from 0 to 9
* @param gzip if true, the output will be in gzip format rather than zlib
* @param bufsize the size of the internal buffers
*/
explicit ozlibstream(std::ostream& output, int level = Z_DEFAULT_COMPRESSION, bool gzip = false, size_t bufsize = 32768):
std::ostream(&buf), buf(output, bufsize, level, 15 + (gzip ? 16 : 0))
{}
///@return the wrapped ostream
std::ostream& get_ostr() const { return buf.get_ostr(); }
///Finishes compression and writes all pending data to the output
void close();
private:
deflate_streambuf buf;
};
}
#endif // OZLIBSTREAM_H_INCLUDED
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