libcarla/include/system/boost/nowide/fstream.hpp
2024-10-18 13:19:59 +08:00

360 lines
13 KiB
C++

//
// Copyright (c) 2012 Artyom Beilis (Tonkikh)
//
// Distributed under the Boost Software License, Version 1.0.
// https://www.boost.org/LICENSE_1_0.txt
#ifndef BOOST_NOWIDE_FSTREAM_HPP_INCLUDED
#define BOOST_NOWIDE_FSTREAM_HPP_INCLUDED
#include <boost/nowide/config.hpp>
#include <boost/nowide/detail/is_path.hpp>
#include <boost/nowide/filebuf.hpp>
#include <istream>
#include <ostream>
#include <utility>
namespace boost {
namespace nowide {
/// \cond INTERNAL
namespace detail {
// clang-format off
struct StreamTypeIn
{
static std::ios_base::openmode mode() { return std::ios_base::in; }
static std::ios_base::openmode mode_modifier() { return mode(); }
template<typename CharType, typename Traits>
struct stream_base{
using type = std::basic_istream<CharType, Traits>;
};
};
struct StreamTypeOut
{
static std::ios_base::openmode mode() { return std::ios_base::out; }
static std::ios_base::openmode mode_modifier() { return mode(); }
template<typename CharType, typename Traits>
struct stream_base{
using type = std::basic_ostream<CharType, Traits>;
};
};
struct StreamTypeInOut
{
static std::ios_base::openmode mode() { return std::ios_base::in | std::ios_base::out; }
static std::ios_base::openmode mode_modifier() { return std::ios_base::openmode(); }
template<typename CharType, typename Traits>
struct stream_base{
using type = std::basic_iostream<CharType, Traits>;
};
};
// clang-format on
/// Base class for all basic_*fstream classes
/// Contains basic_filebuf instance so its pointer can be used to construct basic_*stream
/// Provides common functions to reduce boilerplate code including inheriting from
/// the correct std::basic_[io]stream class and initializing it
/// \tparam T_StreamType One of StreamType* above.
/// Class used instead of value, because openmode::operator| may not be constexpr
/// \tparam FileBufType Discriminator to force a differing ABI if depending on the contained filebuf
template<typename CharType,
typename Traits,
typename T_StreamType,
int FileBufType = BOOST_NOWIDE_USE_FILEBUF_REPLACEMENT>
class fstream_impl;
} // namespace detail
/// \endcond
///
/// \brief Same as std::basic_ifstream<char> but accepts UTF-8 strings under Windows
///
/// Affected by #BOOST_NOWIDE_USE_FILEBUF_REPLACEMENT and #BOOST_NOWIDE_USE_WCHAR_OVERLOADS
template<typename CharType, typename Traits = std::char_traits<CharType>>
class basic_ifstream : public detail::fstream_impl<CharType, Traits, detail::StreamTypeIn>
{
using fstream_impl = detail::fstream_impl<CharType, Traits, detail::StreamTypeIn>;
public:
basic_ifstream()
{}
explicit basic_ifstream(const char* file_name, std::ios_base::openmode mode = std::ios_base::in)
{
open(file_name, mode);
}
#if BOOST_NOWIDE_USE_WCHAR_OVERLOADS
explicit basic_ifstream(const wchar_t* file_name, std::ios_base::openmode mode = std::ios_base::in)
{
open(file_name, mode);
}
#endif
explicit basic_ifstream(const std::string& file_name, std::ios_base::openmode mode = std::ios_base::in)
{
open(file_name, mode);
}
template<typename Path>
explicit basic_ifstream(const Path& file_name,
detail::enable_if_path_t<Path, std::ios_base::openmode> mode = std::ios_base::in)
{
open(file_name, mode);
}
using fstream_impl::open;
using fstream_impl::is_open;
using fstream_impl::close;
using fstream_impl::rdbuf;
using fstream_impl::swap;
basic_ifstream(const basic_ifstream&) = delete;
basic_ifstream& operator=(const basic_ifstream&) = delete;
basic_ifstream(basic_ifstream&& other) noexcept : fstream_impl(std::move(other))
{}
basic_ifstream& operator=(basic_ifstream&& rhs) noexcept
{
fstream_impl::operator=(std::move(rhs));
return *this;
}
};
///
/// \brief Same as std::basic_ofstream<char> but accepts UTF-8 strings under Windows
///
/// Affected by #BOOST_NOWIDE_USE_FILEBUF_REPLACEMENT and #BOOST_NOWIDE_USE_WCHAR_OVERLOADS
template<typename CharType, typename Traits = std::char_traits<CharType>>
class basic_ofstream : public detail::fstream_impl<CharType, Traits, detail::StreamTypeOut>
{
using fstream_impl = detail::fstream_impl<CharType, Traits, detail::StreamTypeOut>;
public:
basic_ofstream()
{}
explicit basic_ofstream(const char* file_name, std::ios_base::openmode mode = std::ios_base::out)
{
open(file_name, mode);
}
#if BOOST_NOWIDE_USE_WCHAR_OVERLOADS
explicit basic_ofstream(const wchar_t* file_name, std::ios_base::openmode mode = std::ios_base::out)
{
open(file_name, mode);
}
#endif
explicit basic_ofstream(const std::string& file_name, std::ios_base::openmode mode = std::ios_base::out)
{
open(file_name, mode);
}
template<typename Path>
explicit basic_ofstream(const Path& file_name,
detail::enable_if_path_t<Path, std::ios_base::openmode> mode = std::ios_base::out)
{
open(file_name, mode);
}
using fstream_impl::open;
using fstream_impl::is_open;
using fstream_impl::close;
using fstream_impl::rdbuf;
using fstream_impl::swap;
basic_ofstream(const basic_ofstream&) = delete;
basic_ofstream& operator=(const basic_ofstream&) = delete;
basic_ofstream(basic_ofstream&& other) noexcept : fstream_impl(std::move(other))
{}
basic_ofstream& operator=(basic_ofstream&& rhs)
{
fstream_impl::operator=(std::move(rhs));
return *this;
}
};
#ifdef BOOST_MSVC
#pragma warning(push)
#pragma warning(disable : 4250) // <class> : inherits <method> via dominance
#endif
///
/// \brief Same as std::basic_fstream<char> but accepts UTF-8 strings under Windows
///
/// Affected by #BOOST_NOWIDE_USE_FILEBUF_REPLACEMENT and #BOOST_NOWIDE_USE_WCHAR_OVERLOADS
template<typename CharType, typename Traits = std::char_traits<CharType>>
class basic_fstream : public detail::fstream_impl<CharType, Traits, detail::StreamTypeInOut>
{
using fstream_impl = detail::fstream_impl<CharType, Traits, detail::StreamTypeInOut>;
public:
basic_fstream()
{}
explicit basic_fstream(const char* file_name,
std::ios_base::openmode mode = std::ios_base::in | std::ios_base::out)
{
open(file_name, mode);
}
#if BOOST_NOWIDE_USE_WCHAR_OVERLOADS
explicit basic_fstream(const wchar_t* file_name,
std::ios_base::openmode mode = std::ios_base::in | std::ios_base::out)
{
open(file_name, mode);
}
#endif
explicit basic_fstream(const std::string& file_name,
std::ios_base::openmode mode = std::ios_base::in | std::ios_base::out)
{
open(file_name, mode);
}
template<typename Path>
explicit basic_fstream(const Path& file_name,
detail::enable_if_path_t<Path, std::ios_base::openmode> mode = std::ios_base::in
| std::ios_base::out)
{
open(file_name, mode);
}
using fstream_impl::open;
using fstream_impl::is_open;
using fstream_impl::close;
using fstream_impl::rdbuf;
using fstream_impl::swap;
basic_fstream(const basic_fstream&) = delete;
basic_fstream& operator=(const basic_fstream&) = delete;
basic_fstream(basic_fstream&& other) noexcept : fstream_impl(std::move(other))
{}
basic_fstream& operator=(basic_fstream&& rhs)
{
fstream_impl::operator=(std::move(rhs));
return *this;
}
};
template<typename CharType, typename Traits>
void swap(basic_ifstream<CharType, Traits>& lhs, basic_ifstream<CharType, Traits>& rhs)
{
lhs.swap(rhs);
}
template<typename CharType, typename Traits>
void swap(basic_ofstream<CharType, Traits>& lhs, basic_ofstream<CharType, Traits>& rhs)
{
lhs.swap(rhs);
}
template<typename CharType, typename Traits>
void swap(basic_fstream<CharType, Traits>& lhs, basic_fstream<CharType, Traits>& rhs)
{
lhs.swap(rhs);
}
///
/// Same as std::filebuf but accepts UTF-8 strings under Windows
///
using filebuf = basic_filebuf<char>;
///
/// Same as std::ifstream but accepts UTF-8 strings under Windows
/// and *\::filesystem::path on all systems
///
using ifstream = basic_ifstream<char>;
///
/// Same as std::ofstream but accepts UTF-8 strings under Windows
/// and *\::filesystem::path on all systems
///
using ofstream = basic_ofstream<char>;
///
/// Same as std::fstream but accepts UTF-8 strings under Windows
/// and *\::filesystem::path on all systems
///
using fstream = basic_fstream<char>;
// Implementation
namespace detail {
/// Holds an instance of T
/// Required to make sure this is constructed first before passing it to sibling classes
template<typename T>
struct buf_holder
{
T buf_;
};
template<typename CharType, typename Traits, typename T_StreamType, int>
class fstream_impl : private buf_holder<basic_filebuf<CharType, Traits>>, // must be first due to init order
public T_StreamType::template stream_base<CharType, Traits>::type
{
using internal_buffer_type = basic_filebuf<CharType, Traits>;
using base_buf_holder = buf_holder<internal_buffer_type>;
using stream_base = typename T_StreamType::template stream_base<CharType, Traits>::type;
public:
using stream_base::setstate;
using stream_base::clear;
protected:
using base_buf_holder::buf_;
fstream_impl() : stream_base(&buf_)
{}
fstream_impl(const fstream_impl&) = delete;
fstream_impl& operator=(const fstream_impl&) = delete;
// coverity[exn_spec_violation]
fstream_impl(fstream_impl&& other) noexcept :
base_buf_holder(std::move(other)), stream_base(std::move(other))
{
this->set_rdbuf(rdbuf());
}
fstream_impl& operator=(fstream_impl&& rhs) noexcept
{
base_buf_holder::operator=(std::move(rhs));
stream_base::operator=(std::move(rhs));
return *this;
}
void swap(fstream_impl& other)
{
stream_base::swap(other);
rdbuf()->swap(*other.rdbuf());
}
void open(const std::string& file_name, std::ios_base::openmode mode = T_StreamType::mode())
{
open(file_name.c_str(), mode);
}
template<typename Path>
detail::enable_if_path_t<Path, void> open(const Path& file_name,
std::ios_base::openmode mode = T_StreamType::mode())
{
open(file_name.c_str(), mode);
}
void open(const char* file_name, std::ios_base::openmode mode = T_StreamType::mode())
{
if(!rdbuf()->open(file_name, mode | T_StreamType::mode_modifier()))
setstate(std::ios_base::failbit);
else
clear();
}
#if BOOST_NOWIDE_USE_WCHAR_OVERLOADS
void open(const wchar_t* file_name, std::ios_base::openmode mode = T_StreamType::mode())
{
if(!rdbuf()->open(file_name, mode | T_StreamType::mode_modifier()))
setstate(std::ios_base::failbit);
else
clear();
}
#endif
bool is_open()
{
return rdbuf()->is_open();
}
bool is_open() const
{
return rdbuf()->is_open();
}
void close()
{
if(!rdbuf()->close())
setstate(std::ios_base::failbit);
}
internal_buffer_type* rdbuf() const
{
return const_cast<internal_buffer_type*>(&buf_);
}
};
#ifdef BOOST_MSVC
#pragma warning(pop)
#endif
} // namespace detail
} // namespace nowide
} // namespace boost
#endif