boost/iostreams/filter/zstd.hpp
// (C) Copyright Reimar Döffinger 2018.
// Based on zstd.hpp by:
// (C) Copyright Milan Svoboda 2008.
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt.)
// See http://www.boost.org/libs/iostreams for documentation.
#ifndef BOOST_IOSTREAMS_ZSTD_HPP_INCLUDED
#define BOOST_IOSTREAMS_ZSTD_HPP_INCLUDED
#if defined(_MSC_VER)
# pragma once
#endif
#include <cassert>
#include <iosfwd> // streamsize.
#include <memory> // allocator, bad_alloc.
#include <new>
#include <boost/config.hpp> // MSVC, STATIC_CONSTANT, DEDUCED_TYPENAME, DINKUM.
#include <boost/detail/workaround.hpp>
#include <boost/iostreams/constants.hpp> // buffer size.
#include <boost/iostreams/detail/config/auto_link.hpp>
#include <boost/iostreams/detail/config/dyn_link.hpp>
#include <boost/iostreams/detail/config/wide_streams.hpp>
#include <boost/iostreams/detail/ios.hpp> // failure, streamsize.
#include <boost/iostreams/filter/symmetric.hpp>
#include <boost/iostreams/pipeline.hpp>
#include <boost/type_traits/is_same.hpp>
// Must come last.
#ifdef BOOST_MSVC
# pragma warning(push)
# pragma warning(disable:4251 4231 4660) // Dependencies not exported.
#endif
#include <boost/config/abi_prefix.hpp>
namespace boost { namespace iostreams {
namespace zstd {
typedef void* (*alloc_func)(void*, size_t, size_t);
typedef void (*free_func)(void*, void*);
// Compression levels
BOOST_IOSTREAMS_DECL extern const uint32_t best_speed;
BOOST_IOSTREAMS_DECL extern const uint32_t best_compression;
BOOST_IOSTREAMS_DECL extern const uint32_t default_compression;
// Status codes
BOOST_IOSTREAMS_DECL extern const int okay;
BOOST_IOSTREAMS_DECL extern const int stream_end;
// Flush codes
BOOST_IOSTREAMS_DECL extern const int finish;
BOOST_IOSTREAMS_DECL extern const int flush;
BOOST_IOSTREAMS_DECL extern const int run;
// Code for current OS
// Null pointer constant.
const int null = 0;
// Default values
} // End namespace zstd.
//
// Class name: zstd_params.
// Description: Encapsulates the parameters passed to zstddec_init
// to customize compression and decompression.
//
struct zstd_params {
// Non-explicit constructor.
zstd_params( uint32_t level = zstd::default_compression )
: level(level)
{ }
uint32_t level;
};
//
// Class name: zstd_error.
// Description: Subclass of std::ios::failure thrown to indicate
// zstd errors other than out-of-memory conditions.
//
class BOOST_IOSTREAMS_DECL zstd_error : public BOOST_IOSTREAMS_FAILURE {
public:
explicit zstd_error(size_t error);
int error() const { return error_; }
static void check BOOST_PREVENT_MACRO_SUBSTITUTION(size_t error);
private:
size_t error_;
};
namespace detail {
template<typename Alloc>
struct zstd_allocator_traits {
#ifndef BOOST_NO_STD_ALLOCATOR
#if defined(BOOST_NO_CXX11_ALLOCATOR)
typedef typename Alloc::template rebind<char>::other type;
#else
typedef typename std::allocator_traits<Alloc>::template rebind_alloc<char> type;
#endif
#else
typedef std::allocator<char> type;
#endif
};
template< typename Alloc,
typename Base = // VC6 workaround (C2516)
BOOST_DEDUCED_TYPENAME zstd_allocator_traits<Alloc>::type >
struct zstd_allocator : private Base {
private:
#if defined(BOOST_NO_CXX11_ALLOCATOR) || defined(BOOST_NO_STD_ALLOCATOR)
typedef typename Base::size_type size_type;
#else
typedef typename std::allocator_traits<Base>::size_type size_type;
#endif
public:
BOOST_STATIC_CONSTANT(bool, custom =
(!is_same<std::allocator<char>, Base>::value));
typedef typename zstd_allocator_traits<Alloc>::type allocator_type;
static void* allocate(void* self, size_t items, size_t size);
static void deallocate(void* self, void* address);
};
class BOOST_IOSTREAMS_DECL zstd_base {
public:
typedef char char_type;
protected:
zstd_base();
~zstd_base();
template<typename Alloc>
void init( const zstd_params& p,
bool compress,
zstd_allocator<Alloc>& zalloc )
{
bool custom = zstd_allocator<Alloc>::custom;
do_init( p, compress,
custom ? zstd_allocator<Alloc>::allocate : 0,
custom ? zstd_allocator<Alloc>::deallocate : 0,
&zalloc );
}
void before( const char*& src_begin, const char* src_end,
char*& dest_begin, char* dest_end );
void after( const char*& src_begin, char*& dest_begin,
bool compress );
int deflate(int action);
int inflate(int action);
void reset(bool compress, bool realloc);
private:
void do_init( const zstd_params& p, bool compress,
zstd::alloc_func,
zstd::free_func,
void* derived );
void* cstream_; // Actual type: ZSTD_CStream *
void* dstream_; // Actual type: ZSTD_DStream *
void* in_; // Actual type: ZSTD_inBuffer *
void* out_; // Actual type: ZSTD_outBuffer *
int eof_;
uint32_t level;
};
//
// Template name: zstd_compressor_impl
// Description: Model of C-Style Filter implementing compression by
// delegating to the zstd function deflate.
//
template<typename Alloc = std::allocator<char> >
class zstd_compressor_impl : public zstd_base, public zstd_allocator<Alloc> {
public:
zstd_compressor_impl(const zstd_params& = zstd::default_compression);
~zstd_compressor_impl();
bool filter( const char*& src_begin, const char* src_end,
char*& dest_begin, char* dest_end, bool flush );
void close();
};
//
// Template name: zstd_decompressor_impl
// Description: Model of C-Style Filter implementing decompression by
// delegating to the zstd function inflate.
//
template<typename Alloc = std::allocator<char> >
class zstd_decompressor_impl : public zstd_base, public zstd_allocator<Alloc> {
public:
zstd_decompressor_impl(const zstd_params&);
zstd_decompressor_impl();
~zstd_decompressor_impl();
bool filter( const char*& begin_in, const char* end_in,
char*& begin_out, char* end_out, bool flush );
void close();
};
} // End namespace detail.
//
// Template name: zstd_compressor
// Description: Model of InputFilter and OutputFilter implementing
// compression using zstd.
//
template<typename Alloc = std::allocator<char> >
struct basic_zstd_compressor
: symmetric_filter<detail::zstd_compressor_impl<Alloc>, Alloc>
{
private:
typedef detail::zstd_compressor_impl<Alloc> impl_type;
typedef symmetric_filter<impl_type, Alloc> base_type;
public:
typedef typename base_type::char_type char_type;
typedef typename base_type::category category;
basic_zstd_compressor( const zstd_params& = zstd::default_compression,
std::streamsize buffer_size = default_device_buffer_size );
};
BOOST_IOSTREAMS_PIPABLE(basic_zstd_compressor, 1)
typedef basic_zstd_compressor<> zstd_compressor;
//
// Template name: zstd_decompressor
// Description: Model of InputFilter and OutputFilter implementing
// decompression using zstd.
//
template<typename Alloc = std::allocator<char> >
struct basic_zstd_decompressor
: symmetric_filter<detail::zstd_decompressor_impl<Alloc>, Alloc>
{
private:
typedef detail::zstd_decompressor_impl<Alloc> impl_type;
typedef symmetric_filter<impl_type, Alloc> base_type;
public:
typedef typename base_type::char_type char_type;
typedef typename base_type::category category;
basic_zstd_decompressor( std::streamsize buffer_size = default_device_buffer_size );
basic_zstd_decompressor( const zstd_params& p,
std::streamsize buffer_size = default_device_buffer_size );
};
BOOST_IOSTREAMS_PIPABLE(basic_zstd_decompressor, 1)
typedef basic_zstd_decompressor<> zstd_decompressor;
//----------------------------------------------------------------------------//
//------------------Implementation of zstd_allocator--------------------------//
namespace detail {
template<typename Alloc, typename Base>
void* zstd_allocator<Alloc, Base>::allocate
(void* self, size_t items, size_t size)
{
size_type len = items * size;
char* ptr =
static_cast<allocator_type*>(self)->allocate
(len + sizeof(size_type)
#if BOOST_WORKAROUND(BOOST_DINKUMWARE_STDLIB, == 1)
, (char*)0
#endif
);
*reinterpret_cast<size_type*>(ptr) = len;
return ptr + sizeof(size_type);
}
template<typename Alloc, typename Base>
void zstd_allocator<Alloc, Base>::deallocate(void* self, void* address)
{
char* ptr = reinterpret_cast<char*>(address) - sizeof(size_type);
size_type len = *reinterpret_cast<size_type*>(ptr) + sizeof(size_type);
static_cast<allocator_type*>(self)->deallocate(ptr, len);
}
//------------------Implementation of zstd_compressor_impl--------------------//
template<typename Alloc>
zstd_compressor_impl<Alloc>::zstd_compressor_impl(const zstd_params& p)
{ init(p, true, static_cast<zstd_allocator<Alloc>&>(*this)); }
template<typename Alloc>
zstd_compressor_impl<Alloc>::~zstd_compressor_impl()
{ reset(true, false); }
template<typename Alloc>
bool zstd_compressor_impl<Alloc>::filter
( const char*& src_begin, const char* src_end,
char*& dest_begin, char* dest_end, bool flush )
{
before(src_begin, src_end, dest_begin, dest_end);
int result = deflate(flush ? zstd::finish : zstd::run);
after(src_begin, dest_begin, true);
return result != zstd::stream_end;
}
template<typename Alloc>
void zstd_compressor_impl<Alloc>::close() { reset(true, true); }
//------------------Implementation of zstd_decompressor_impl------------------//
template<typename Alloc>
zstd_decompressor_impl<Alloc>::zstd_decompressor_impl(const zstd_params& p)
{ init(p, false, static_cast<zstd_allocator<Alloc>&>(*this)); }
template<typename Alloc>
zstd_decompressor_impl<Alloc>::~zstd_decompressor_impl()
{ reset(false, false); }
template<typename Alloc>
zstd_decompressor_impl<Alloc>::zstd_decompressor_impl()
{
zstd_params p;
init(p, false, static_cast<zstd_allocator<Alloc>&>(*this));
}
template<typename Alloc>
bool zstd_decompressor_impl<Alloc>::filter
( const char*& src_begin, const char* src_end,
char*& dest_begin, char* dest_end, bool flush )
{
before(src_begin, src_end, dest_begin, dest_end);
int result = inflate(flush ? zstd::finish : zstd::run);
after(src_begin, dest_begin, false);
return result != zstd::stream_end;
}
template<typename Alloc>
void zstd_decompressor_impl<Alloc>::close() { reset(false, true); }
} // End namespace detail.
//------------------Implementation of zstd_compressor-----------------------//
template<typename Alloc>
basic_zstd_compressor<Alloc>::basic_zstd_compressor
(const zstd_params& p, std::streamsize buffer_size)
: base_type(buffer_size, p) { }
//------------------Implementation of zstd_decompressor-----------------------//
template<typename Alloc>
basic_zstd_decompressor<Alloc>::basic_zstd_decompressor
(std::streamsize buffer_size)
: base_type(buffer_size) { }
template<typename Alloc>
basic_zstd_decompressor<Alloc>::basic_zstd_decompressor
(const zstd_params& p, std::streamsize buffer_size)
: base_type(buffer_size, p) { }
//----------------------------------------------------------------------------//
} } // End namespaces iostreams, boost.
#include <boost/config/abi_suffix.hpp> // Pops abi_suffix.hpp pragmas.
#ifdef BOOST_MSVC
# pragma warning(pop)
#endif
#endif // #ifndef BOOST_IOSTREAMS_ZSTD_HPP_INCLUDED