vn-verdnaturachat/ios/Pods/boost-for-react-native/boost/iostreams/detail/restrict_impl.hpp

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/*
* 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.
* File: boost/iostreams/detail/restrict_impl.hpp
* Date: Sun Jan 06 12:57:30 MST 2008
* Copyright: 2007-2008 CodeRage, LLC
* Author: Jonathan Turkanis
* Contact: turkanis at coderage dot com
*
* If included with the macro BOOST_IOSTREAMS_RESTRICT undefined, defines the
* class template boost::iostreams::restriction. If included with the macro
* BOOST_IOSTREAMS_RESTRICT defined as an identifier, defines the overloaded
* function template boost::iostreams::BOOST_IOSTREAMS_RESTRICT, and object
* generator for boost::iostreams::restriction.
*
* This design allows <boost/iostreams/restrict.hpp> and
* <boost/iostreams/slice.hpp> to share an implementation.
*/
#if !defined(BOOST_IOSTREAMS_RESTRICT_IMPL_HPP_INCLUDED) && \
!defined(BOOST_IOSTREAMS_RESTRICT)
# define BOOST_IOSTREAMS_RESTRICT_IMPL_HPP_INCLUDED
//------------------Implementation of restriction-----------------------------//
# include <algorithm> // min.
# include <utility> // pair.
# include <boost/cstdint.hpp> // intmax_t.
# include <boost/config.hpp> // DEDUCED_TYPENAME.
# include <boost/iostreams/categories.hpp>
# include <boost/iostreams/char_traits.hpp>
# include <boost/iostreams/detail/adapter/device_adapter.hpp>
# include <boost/iostreams/detail/adapter/filter_adapter.hpp>
# include <boost/iostreams/detail/call_traits.hpp>
# include <boost/iostreams/detail/enable_if_stream.hpp>
# include <boost/iostreams/detail/error.hpp>
# include <boost/iostreams/detail/ios.hpp> // failure.
# include <boost/iostreams/detail/select.hpp>
# include <boost/iostreams/operations.hpp>
# include <boost/iostreams/skip.hpp>
# include <boost/iostreams/traits.hpp> // mode_of, is_direct.
# include <boost/mpl/bool.hpp>
# include <boost/static_assert.hpp>
# include <boost/throw_exception.hpp>
# include <boost/type_traits/is_convertible.hpp>
# include <boost/iostreams/detail/config/disable_warnings.hpp>
namespace boost { namespace iostreams {
namespace detail {
//
// Template name: restricted_indirect_device.
// Description: Provides an restricted view of an indirect Device.
// Template parameters:
// Device - An indirect model of Device that models either Source or
// SeekableDevice.
//
template<typename Device>
class restricted_indirect_device : public device_adapter<Device> {
private:
typedef typename detail::param_type<Device>::type param_type;
public:
typedef typename char_type_of<Device>::type char_type;
typedef typename mode_of<Device>::type mode;
BOOST_STATIC_ASSERT(!(is_convertible<mode, detail::two_sequence>::value));
struct category
: mode,
device_tag,
closable_tag,
flushable_tag,
localizable_tag,
optimally_buffered_tag
{ };
restricted_indirect_device( param_type dev, stream_offset off,
stream_offset len = -1 );
std::streamsize read(char_type* s, std::streamsize n);
std::streamsize write(const char_type* s, std::streamsize n);
std::streampos seek(stream_offset off, BOOST_IOS::seekdir way);
private:
stream_offset beg_, pos_, end_;
};
//
// Template name: restricted_direct_device.
// Description: Provides an restricted view of a Direct Device.
// Template parameters:
// Device - A model of Direct and Device.
//
template<typename Device>
class restricted_direct_device : public device_adapter<Device> {
public:
typedef typename char_type_of<Device>::type char_type;
typedef std::pair<char_type*, char_type*> pair_type;
typedef typename mode_of<Device>::type mode;
BOOST_STATIC_ASSERT(!(is_convertible<mode, detail::two_sequence>::value));
struct category
: mode_of<Device>::type,
device_tag,
direct_tag,
closable_tag,
localizable_tag
{ };
restricted_direct_device( const Device& dev, stream_offset off,
stream_offset len = -1 );
pair_type input_sequence();
pair_type output_sequence();
private:
pair_type sequence(mpl::true_);
pair_type sequence(mpl::false_);
char_type *beg_, *end_;
};
//
// Template name: restricted_filter.
// Description: Provides an restricted view of a Filter.
// Template parameters:
// Filter - An indirect model of Filter.
//
template<typename Filter>
class restricted_filter : public filter_adapter<Filter> {
public:
typedef typename char_type_of<Filter>::type char_type;
typedef typename mode_of<Filter>::type mode;
BOOST_STATIC_ASSERT(!(is_convertible<mode, detail::two_sequence>::value));
struct category
: mode,
filter_tag,
multichar_tag,
closable_tag,
localizable_tag,
optimally_buffered_tag
{ };
restricted_filter( const Filter& flt, stream_offset off,
stream_offset len = -1 );
template<typename Source>
std::streamsize read(Source& src, char_type* s, std::streamsize n)
{
using namespace std;
if (!open_)
open(src, BOOST_IOS::in);
std::streamsize amt =
end_ != -1 ?
(std::min) (n, static_cast<std::streamsize>(end_ - pos_)) :
n;
std::streamsize result =
iostreams::read(this->component(), src, s, amt);
if (result != -1)
pos_ += result;
return result;
}
template<typename Sink>
std::streamsize write(Sink& snk, const char_type* s, std::streamsize n)
{
if (!open_)
open(snk, BOOST_IOS::out);
if (end_ != -1 && pos_ + n >= end_) {
if(pos_ < end_)
pos_ += iostreams::write(this->component(),
snk, s, end_ - pos_);
boost::throw_exception(bad_write());
}
std::streamsize result =
iostreams::write(this->component(), snk, s, n);
pos_ += result;
return result;
}
template<typename Device>
std::streampos seek(Device& dev, stream_offset off, BOOST_IOS::seekdir way)
{
stream_offset next;
if (way == BOOST_IOS::beg) {
next = beg_ + off;
} else if (way == BOOST_IOS::cur) {
next = pos_ + off;
} else if (end_ != -1) {
next = end_ + off;
} else {
// Restriction is half-open; seek relative to the actual end.
pos_ = this->component().seek(dev, off, BOOST_IOS::end);
if (pos_ < beg_)
boost::throw_exception(bad_seek());
return offset_to_position(pos_ - beg_);
}
if (next < beg_ || (end_ != -1 && next >= end_))
boost::throw_exception(bad_seek());
pos_ = this->component().seek(dev, next, BOOST_IOS::cur);
return offset_to_position(pos_ - beg_);
}
template<typename Device>
void close(Device& dev)
{
open_ = false;
detail::close_all(this->component(), dev);
}
template<typename Device>
void close(Device& dev, BOOST_IOS::openmode which)
{
open_ = false;
iostreams::close(this->component(), dev, which);
}
private:
template<typename Device>
void open(Device& dev, BOOST_IOS::openmode which)
{
typedef typename is_convertible<mode, dual_use>::type is_dual_use;
open_ = true;
which = is_dual_use() ? which : (BOOST_IOS::in | BOOST_IOS::out);
iostreams::skip(this->component(), dev, beg_, which);
}
stream_offset beg_, pos_, end_;
bool open_;
};
template<typename T>
struct restriction_traits
: iostreams::select< // Disambiguation for Tru64.
is_filter<T>, restricted_filter<T>,
is_direct<T>, restricted_direct_device<T>,
else_, restricted_indirect_device<T>
>
{ };
} // End namespace detail.
template<typename T>
struct restriction : public detail::restriction_traits<T>::type {
typedef typename detail::param_type<T>::type param_type;
typedef typename detail::restriction_traits<T>::type base_type;
restriction(param_type t, stream_offset off, stream_offset len = -1)
: base_type(t, off, len)
{ }
};
namespace detail {
//--------------Implementation of restricted_indirect_device------------------//
template<typename Device>
restricted_indirect_device<Device>::restricted_indirect_device
(param_type dev, stream_offset off, stream_offset len)
: device_adapter<Device>(dev), beg_(off), pos_(off),
end_(len != -1 ? off + len : -1)
{
if (len < -1 || off < 0)
boost::throw_exception(BOOST_IOSTREAMS_FAILURE("bad offset"));
iostreams::skip(this->component(), off);
}
template<typename Device>
inline std::streamsize restricted_indirect_device<Device>::read
(char_type* s, std::streamsize n)
{
using namespace std;
std::streamsize amt =
end_ != -1 ?
(std::min) (n, static_cast<std::streamsize>(end_ - pos_)) :
n;
std::streamsize result = iostreams::read(this->component(), s, amt);
if (result != -1)
pos_ += result;
return result;
}
template<typename Device>
inline std::streamsize restricted_indirect_device<Device>::write
(const char_type* s, std::streamsize n)
{
if (end_ != -1 && pos_ + n >= end_) {
if(pos_ < end_)
pos_ += iostreams::write(this->component(), s, end_ - pos_);
boost::throw_exception(bad_write());
}
std::streamsize result = iostreams::write(this->component(), s, n);
pos_ += result;
return result;
}
template<typename Device>
std::streampos restricted_indirect_device<Device>::seek
(stream_offset off, BOOST_IOS::seekdir way)
{
stream_offset next;
if (way == BOOST_IOS::beg) {
next = beg_ + off;
} else if (way == BOOST_IOS::cur) {
next = pos_ + off;
} else if (end_ != -1) {
next = end_ + off;
} else {
// Restriction is half-open; seek relative to the actual end.
pos_ = iostreams::seek(this->component(), off, BOOST_IOS::end);
if (pos_ < beg_)
boost::throw_exception(bad_seek());
return offset_to_position(pos_ - beg_);
}
if (next < beg_ || (end_ != -1 && next > end_))
boost::throw_exception(bad_seek());
pos_ = iostreams::seek(this->component(), next - pos_, BOOST_IOS::cur);
return offset_to_position(pos_ - beg_);
}
//--------------Implementation of restricted_direct_device--------------------//
template<typename Device>
restricted_direct_device<Device>::restricted_direct_device
(const Device& dev, stream_offset off, stream_offset len)
: device_adapter<Device>(dev), beg_(0), end_(0)
{
std::pair<char_type*, char_type*> seq =
sequence(is_convertible<category, input>());
if ( off < 0 || len < -1 ||
(len != -1 && off + len > seq.second - seq.first) )
{
boost::throw_exception(BOOST_IOSTREAMS_FAILURE("bad offset"));
}
beg_ = seq.first + off;
end_ = len != -1 ?
seq.first + off + len :
seq.second;
}
template<typename Device>
typename restricted_direct_device<Device>::pair_type
restricted_direct_device<Device>::input_sequence()
{
BOOST_STATIC_ASSERT((is_convertible<category, input>::value));
return std::make_pair(beg_, end_);
}
template<typename Device>
typename restricted_direct_device<Device>::pair_type
restricted_direct_device<Device>::output_sequence()
{
BOOST_STATIC_ASSERT((is_convertible<category, output>::value));
return std::make_pair(beg_, end_);
}
template<typename Device>
typename restricted_direct_device<Device>::pair_type
restricted_direct_device<Device>::sequence(mpl::true_)
{ return iostreams::input_sequence(this->component()); }
template<typename Device>
typename restricted_direct_device<Device>::pair_type
restricted_direct_device<Device>::sequence(mpl::false_)
{ return iostreams::output_sequence(this->component()); }
//--------------Implementation of restricted_filter---------------------------//
template<typename Filter>
restricted_filter<Filter>::restricted_filter
(const Filter& flt, stream_offset off, stream_offset len)
: filter_adapter<Filter>(flt), beg_(off),
pos_(off), end_(len != -1 ? off + len : -1), open_(false)
{
if (len < -1 || off < 0)
boost::throw_exception(BOOST_IOSTREAMS_FAILURE("bad offset"));
}
} // End namespace detail.
} } // End namespaces iostreams, boost.
#elif defined(BOOST_IOSTREAMS_RESTRICT)
namespace boost { namespace iostreams {
//--------------Implementation of restrict/slice------------------------------//
// Note: The following workarounds are patterned after resolve.hpp. It has not
// yet been confirmed that they are necessary.
# ifndef BOOST_IOSTREAMS_BROKEN_OVERLOAD_RESOLUTION //------------------------//
# ifndef BOOST_IOSTREAMS_NO_STREAM_TEMPLATES //------------------------------//
template<typename T>
restriction<T>
BOOST_IOSTREAMS_RESTRICT( const T& t, stream_offset off, stream_offset len = -1
BOOST_IOSTREAMS_DISABLE_IF_STREAM(T) )
{ return restriction<T>(t, off, len); }
template<typename Ch, typename Tr>
restriction< std::basic_streambuf<Ch, Tr> >
BOOST_IOSTREAMS_RESTRICT( std::basic_streambuf<Ch, Tr>& sb, stream_offset off,
stream_offset len = -1 )
{ return restriction< std::basic_streambuf<Ch, Tr> >(sb, off, len); }
template<typename Ch, typename Tr>
restriction< std::basic_istream<Ch, Tr> >
BOOST_IOSTREAMS_RESTRICT
(std::basic_istream<Ch, Tr>& is, stream_offset off, stream_offset len = -1)
{ return restriction< std::basic_istream<Ch, Tr> >(is, off, len); }
template<typename Ch, typename Tr>
restriction< std::basic_ostream<Ch, Tr> >
BOOST_IOSTREAMS_RESTRICT
(std::basic_ostream<Ch, Tr>& os, stream_offset off, stream_offset len = -1)
{ return restriction< std::basic_ostream<Ch, Tr> >(os, off, len); }
template<typename Ch, typename Tr>
restriction< std::basic_iostream<Ch, Tr> >
BOOST_IOSTREAMS_RESTRICT
(std::basic_iostream<Ch, Tr>& io, stream_offset off, stream_offset len = -1)
{ return restriction< std::basic_iostream<Ch, Tr> >(io, off, len); }
# else // # ifndef BOOST_IOSTREAMS_NO_STREAM_TEMPLATES //--------------------//
template<typename T>
restriction<T>
BOOST_IOSTREAMS_RESTRICT( const T& t, stream_offset off, stream_offset len = -1
BOOST_IOSTREAMS_DISABLE_IF_STREAM(T) )
{ return restriction<T>(t, off, len); }
restriction<std::streambuf>
BOOST_IOSTREAMS_RESTRICT
(std::streambuf& sb, stream_offset off, stream_offset len = -1)
{ return restriction<std::streambuf>(sb, off, len); }
restriction<std::istream>
BOOST_IOSTREAMS_RESTRICT
(std::istream<Ch, Tr>& is, stream_offset off, stream_offset len = -1)
{ return restriction<std::istream>(is, off, len); }
restriction<std::ostream>
BOOST_IOSTREAMS_RESTRICT
(std::ostream<Ch, Tr>& os, stream_offset off, stream_offset len = -1)
{ return restriction<std::ostream>(os, off, len); }
restriction<std::iostream>
BOOST_IOSTREAMS_RESTRICT
(std::iostream<Ch, Tr>& io, stream_offset off, stream_offset len = -1)
{ return restriction<std::iostream>(io, off, len); }
# endif // # ifndef BOOST_IOSTREAMS_NO_STREAM_TEMPLATES //-------------------//
# else // #ifndef BOOST_IOSTREAMS_BROKEN_OVERLOAD_RESOLUTION //---------------//
template<typename T>
restriction<T>
BOOST_IOSTREAMS_RESTRICT
(const T& t, stream_offset off, stream_offset len, mpl::true_)
{ // Bad overload resolution.
return restriction<T>(const_cast<T&>(t, off, len));
}
template<typename T>
restriction<T>
BOOST_IOSTREAMS_RESTRICT
(const T& t, stream_offset off, stream_offset len, mpl::false_)
{ return restriction<T>(t, off, len); }
template<typename T>
restriction<T>
BOOST_IOSTREAMS_RESTRICT( const T& t, stream_offset off, stream_offset len = -1
BOOST_IOSTREAMS_DISABLE_IF_STREAM(T) )
{ return BOOST_IOSTREAMS_RESTRICT(t, off, len, is_std_io<T>()); }
# if !BOOST_WORKAROUND(__BORLANDC__, < 0x600) && \
!defined(__GNUC__) // ---------------------------------------------------//
template<typename T>
restriction<T>
BOOST_IOSTREAMS_RESTRICT(T& t, stream_offset off, stream_offset len = -1)
{ return restriction<T>(t, off, len); }
# endif // Borland 5.x or GCC //-------------------------------//
# endif // #ifndef BOOST_IOSTREAMS_BROKEN_OVERLOAD_RESOLUTION //--------------//
} } // End namespaces iostreams, boost.
#endif // #if !defined(BOOST_IOSTREAMS_RESTRICT_IMPL_HPP_INCLUDED) ...