chromium/third_party/libc++/src/include/fstream

// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#ifndef _LIBCPP_FSTREAM
#define _LIBCPP_FSTREAM

/*
    fstream synopsis

template <class charT, class traits = char_traits<charT> >
class basic_filebuf
    : public basic_streambuf<charT, traits>
{
public:
    typedef charT                          char_type;
    typedef traits                         traits_type;
    typedef typename traits_type::int_type int_type;
    typedef typename traits_type::pos_type pos_type;
    typedef typename traits_type::off_type off_type;

    // 27.9.1.2 Constructors/destructor:
    basic_filebuf();
    basic_filebuf(basic_filebuf&& rhs);
    virtual ~basic_filebuf();

    // 27.9.1.3 Assign/swap:
    basic_filebuf& operator=(basic_filebuf&& rhs);
    void swap(basic_filebuf& rhs);

    // 27.9.1.4 Members:
    bool is_open() const;
    basic_filebuf* open(const char* s, ios_base::openmode mode);
    basic_filebuf* open(const string& s, ios_base::openmode mode);
    basic_filebuf* open(const filesystem::path& p, ios_base::openmode mode); // C++17
    basic_filebuf* close();

protected:
    // 27.9.1.5 Overridden virtual functions:
    virtual streamsize showmanyc();
    virtual int_type underflow();
    virtual int_type uflow();
    virtual int_type pbackfail(int_type c = traits_type::eof());
    virtual int_type overflow (int_type c = traits_type::eof());
    virtual basic_streambuf<char_type, traits_type>* setbuf(char_type* s, streamsize n);
    virtual pos_type seekoff(off_type off, ios_base::seekdir way,
                             ios_base::openmode which = ios_base::in | ios_base::out);
    virtual pos_type seekpos(pos_type sp,
                             ios_base::openmode which = ios_base::in | ios_base::out);
    virtual int sync();
    virtual void imbue(const locale& loc);
};

template <class charT, class traits>
  void
  swap(basic_filebuf<charT, traits>& x, basic_filebuf<charT, traits>& y);

typedef basic_filebuf<char>    filebuf;
typedef basic_filebuf<wchar_t> wfilebuf;

template <class charT, class traits = char_traits<charT> >
class basic_ifstream
    : public basic_istream<charT,traits>
{
public:
    typedef charT                          char_type;
    typedef traits                         traits_type;
    typedef typename traits_type::int_type int_type;
    typedef typename traits_type::pos_type pos_type;
    typedef typename traits_type::off_type off_type;
    using native_handle_type = typename basic_filebuf<charT, traits>::native_handle_type; // Since C++26

    basic_ifstream();
    explicit basic_ifstream(const char* s, ios_base::openmode mode = ios_base::in);
    explicit basic_ifstream(const string& s, ios_base::openmode mode = ios_base::in);
    template<class T>
    explicit basic_ifstream(const T& s, ios_base::openmode mode = ios_base::in); // Since C++17
    basic_ifstream(basic_ifstream&& rhs);

    basic_ifstream& operator=(basic_ifstream&& rhs);
    void swap(basic_ifstream& rhs);

    basic_filebuf<char_type, traits_type>* rdbuf() const;
    native_handle_type native_handle() const noexcept; // Since C++26
    bool is_open() const;
    void open(const char* s, ios_base::openmode mode = ios_base::in);
    void open(const string& s, ios_base::openmode mode = ios_base::in);
    void open(const filesystem::path& s, ios_base::openmode mode = ios_base::in); // C++17

    void close();
};

template <class charT, class traits>
  void
  swap(basic_ifstream<charT, traits>& x, basic_ifstream<charT, traits>& y);

typedef basic_ifstream<char>    ifstream;
typedef basic_ifstream<wchar_t> wifstream;

template <class charT, class traits = char_traits<charT> >
class basic_ofstream
    : public basic_ostream<charT,traits>
{
public:
    typedef charT                          char_type;
    typedef traits                         traits_type;
    typedef typename traits_type::int_type int_type;
    typedef typename traits_type::pos_type pos_type;
    typedef typename traits_type::off_type off_type;
    using native_handle_type = typename basic_filebuf<charT, traits>::native_handle_type; // Since C++26

    basic_ofstream();
    explicit basic_ofstream(const char* s, ios_base::openmode mode = ios_base::out);
    explicit basic_ofstream(const string& s, ios_base::openmode mode = ios_base::out);
    template<class T>
    explicit basic_ofstream(const T& s, ios_base::openmode mode = ios_base::out); // Since C++17
    basic_ofstream(basic_ofstream&& rhs);

    basic_ofstream& operator=(basic_ofstream&& rhs);
    void swap(basic_ofstream& rhs);

    basic_filebuf<char_type, traits_type>* rdbuf() const;
    native_handle_type native_handle() const noexcept; // Since C++26

    bool is_open() const;
    void open(const char* s, ios_base::openmode mode = ios_base::out);
    void open(const string& s, ios_base::openmode mode = ios_base::out);
    void open(const filesystem::path& p,
              ios_base::openmode mode = ios_base::out); // C++17

    void close();
};

template <class charT, class traits>
  void
  swap(basic_ofstream<charT, traits>& x, basic_ofstream<charT, traits>& y);

typedef basic_ofstream<char>    ofstream;
typedef basic_ofstream<wchar_t> wofstream;

template <class charT, class traits=char_traits<charT> >
class basic_fstream
    : public basic_iostream<charT,traits>
{
public:
    typedef charT                          char_type;
    typedef traits                         traits_type;
    typedef typename traits_type::int_type int_type;
    typedef typename traits_type::pos_type pos_type;
    typedef typename traits_type::off_type off_type;
    using native_handle_type = typename basic_filebuf<charT, traits>::native_handle_type; // Since C++26

    basic_fstream();
    explicit basic_fstream(const char* s, ios_base::openmode mode = ios_base::in|ios_base::out);
    explicit basic_fstream(const string& s, ios_base::openmode mode = ios_base::in|ios_base::out);
    template<class T>
    explicit basic_fstream(const T& s, ios_base::openmode mode = ios_base::in | ios_base::out); // Since C++17
    basic_fstream(basic_fstream&& rhs);

    basic_fstream& operator=(basic_fstream&& rhs);
    void swap(basic_fstream& rhs);

    basic_filebuf<char_type, traits_type>* rdbuf() const;
    native_handle_type native_handle() const noexcept; // Since C++26
    bool is_open() const;
    void open(const char* s, ios_base::openmode mode = ios_base::in|ios_base::out);
    void open(const string& s, ios_base::openmode mode = ios_base::in|ios_base::out);
    void open(const filesystem::path& s,
              ios_base::openmode mode = ios_base::in|ios_base::out); // C++17

    void close();
};

template <class charT, class traits>
  void swap(basic_fstream<charT, traits>& x, basic_fstream<charT, traits>& y);

typedef basic_fstream<char>    fstream;
typedef basic_fstream<wchar_t> wfstream;

}  // std

*/

#include <__algorithm/max.h>
#include <__assert>
#include <__config>
#include <__fwd/fstream.h>
#include <__locale>
#include <__memory/addressof.h>
#include <__type_traits/enable_if.h>
#include <__type_traits/is_same.h>
#include <__utility/move.h>
#include <__utility/swap.h>
#include <__utility/unreachable.h>
#include <cstdio>
#include <filesystem>
#include <istream>
#include <ostream>
#include <typeinfo>
#include <version>

#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#  pragma GCC system_header
#endif

_LIBCPP_PUSH_MACROS
#include <__undef_macros>

#if defined(_LIBCPP_MSVCRT) || defined(_NEWLIB_VERSION)
#define _LIBCPP_HAS_NO_OFF_T_FUNCTIONS
#endif

#if !defined(_LIBCPP_HAS_NO_FILESYSTEM)

_LIBCPP_BEGIN_NAMESPACE_STD

#  if _LIBCPP_STD_VER >= 26 && defined(_LIBCPP_WIN32API)
_LIBCPP_EXPORTED_FROM_ABI void* __filebuf_windows_native_handle(FILE* __file) noexcept;
#  endif

template <class _CharT, class _Traits>
class _LIBCPP_TEMPLATE_VIS basic_filebuf : public basic_streambuf<_CharT, _Traits> { … };

template <class _CharT, class _Traits>
basic_filebuf<_CharT, _Traits>::basic_filebuf()
    : … { … }

template <class _CharT, class _Traits>
basic_filebuf<_CharT, _Traits>::basic_filebuf(basic_filebuf&& __rhs) : … { … }

template <class _CharT, class _Traits>
inline basic_filebuf<_CharT, _Traits>& basic_filebuf<_CharT, _Traits>::operator=(basic_filebuf&& __rhs) { … }

template <class _CharT, class _Traits>
basic_filebuf<_CharT, _Traits>::~basic_filebuf() { … }

template <class _CharT, class _Traits>
void basic_filebuf<_CharT, _Traits>::swap(basic_filebuf& __rhs) { … }

template <class _CharT, class _Traits>
inline _LIBCPP_HIDE_FROM_ABI void swap(basic_filebuf<_CharT, _Traits>& __x, basic_filebuf<_CharT, _Traits>& __y) { … }

template <class _CharT, class _Traits>
inline bool basic_filebuf<_CharT, _Traits>::is_open() const { … }

template <class _CharT, class _Traits>
const char* basic_filebuf<_CharT, _Traits>::__make_mdstring(ios_base::openmode __mode) _NOEXCEPT { … }

#  ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
template <class _CharT, class _Traits>
const wchar_t* basic_filebuf<_CharT, _Traits>::__make_mdwstring(ios_base::openmode __mode) _NOEXCEPT {
  switch (__mode & ~ios_base::ate) {
  case ios_base::out:
  case ios_base::out | ios_base::trunc:
    return L"w";
  case ios_base::out | ios_base::app:
  case ios_base::app:
    return L"a";
  case ios_base::in:
    return L"r";
  case ios_base::in | ios_base::out:
    return L"r+";
  case ios_base::in | ios_base::out | ios_base::trunc:
    return L"w+";
  case ios_base::in | ios_base::out | ios_base::app:
  case ios_base::in | ios_base::app:
    return L"a+";
  case ios_base::out | ios_base::binary:
  case ios_base::out | ios_base::trunc | ios_base::binary:
    return L"wb";
  case ios_base::out | ios_base::app | ios_base::binary:
  case ios_base::app | ios_base::binary:
    return L"ab";
  case ios_base::in | ios_base::binary:
    return L"rb";
  case ios_base::in | ios_base::out | ios_base::binary:
    return L"r+b";
  case ios_base::in | ios_base::out | ios_base::trunc | ios_base::binary:
    return L"w+b";
  case ios_base::in | ios_base::out | ios_base::app | ios_base::binary:
  case ios_base::in | ios_base::app | ios_base::binary:
    return L"a+b";
#    if _LIBCPP_STD_VER >= 23
  case ios_base::out | ios_base::noreplace:
  case ios_base::out | ios_base::trunc | ios_base::noreplace:
    return L"wx";
  case ios_base::in | ios_base::out | ios_base::trunc | ios_base::noreplace:
    return L"w+x";
  case ios_base::out | ios_base::binary | ios_base::noreplace:
  case ios_base::out | ios_base::trunc | ios_base::binary | ios_base::noreplace:
    return L"wbx";
  case ios_base::in | ios_base::out | ios_base::trunc | ios_base::binary | ios_base::noreplace:
    return L"w+bx";
#    endif // _LIBCPP_STD_VER >= 23
  default:
    return nullptr;
  }
  __libcpp_unreachable();
}
#  endif

template <class _CharT, class _Traits>
basic_filebuf<_CharT, _Traits>* basic_filebuf<_CharT, _Traits>::open(const char* __s, ios_base::openmode __mode) { … }

template <class _CharT, class _Traits>
inline basic_filebuf<_CharT, _Traits>* basic_filebuf<_CharT, _Traits>::__open(int __fd, ios_base::openmode __mode) { … }

#  ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
// This is basically the same as the char* overload except that it uses _wfopen
// and long mode strings.
template <class _CharT, class _Traits>
basic_filebuf<_CharT, _Traits>* basic_filebuf<_CharT, _Traits>::open(const wchar_t* __s, ios_base::openmode __mode) {
  if (__file_)
    return nullptr;
  const wchar_t* __mdstr = __make_mdwstring(__mode);
  if (!__mdstr)
    return nullptr;

  return __do_open(_wfopen(__s, __mdstr), __mode);
}
#  endif

template <class _CharT, class _Traits>
inline basic_filebuf<_CharT, _Traits>*
basic_filebuf<_CharT, _Traits>::open(const string& __s, ios_base::openmode __mode) { … }

template <class _CharT, class _Traits>
basic_filebuf<_CharT, _Traits>* basic_filebuf<_CharT, _Traits>::close() { … }

template <class _CharT, class _Traits>
typename basic_filebuf<_CharT, _Traits>::int_type basic_filebuf<_CharT, _Traits>::underflow() { … }

template <class _CharT, class _Traits>
typename basic_filebuf<_CharT, _Traits>::int_type basic_filebuf<_CharT, _Traits>::pbackfail(int_type __c) { … }

template <class _CharT, class _Traits>
typename basic_filebuf<_CharT, _Traits>::int_type basic_filebuf<_CharT, _Traits>::overflow(int_type __c) { … }

template <class _CharT, class _Traits>
basic_streambuf<_CharT, _Traits>* basic_filebuf<_CharT, _Traits>::setbuf(char_type* __s, streamsize __n) { … }

template <class _CharT, class _Traits>
typename basic_filebuf<_CharT, _Traits>::pos_type
basic_filebuf<_CharT, _Traits>::seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode) { … }

template <class _CharT, class _Traits>
typename basic_filebuf<_CharT, _Traits>::pos_type
basic_filebuf<_CharT, _Traits>::seekpos(pos_type __sp, ios_base::openmode) { … }

template <class _CharT, class _Traits>
int basic_filebuf<_CharT, _Traits>::sync() { … }

template <class _CharT, class _Traits>
void basic_filebuf<_CharT, _Traits>::imbue(const locale& __loc) { … }

template <class _CharT, class _Traits>
bool basic_filebuf<_CharT, _Traits>::__read_mode() { … }

template <class _CharT, class _Traits>
void basic_filebuf<_CharT, _Traits>::__write_mode() { … }

// basic_ifstream

template <class _CharT, class _Traits>
class _LIBCPP_TEMPLATE_VIS basic_ifstream : public basic_istream<_CharT, _Traits> { … };

template <class _CharT, class _Traits>
inline basic_ifstream<_CharT, _Traits>::basic_ifstream()
    : … { … }

template <class _CharT, class _Traits>
inline basic_ifstream<_CharT, _Traits>::basic_ifstream(const char* __s, ios_base::openmode __mode)
    : … { … }

#  ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
template <class _CharT, class _Traits>
inline basic_ifstream<_CharT, _Traits>::basic_ifstream(const wchar_t* __s, ios_base::openmode __mode)
    : basic_istream<char_type, traits_type>(std::addressof(__sb_)) {
  if (__sb_.open(__s, __mode | ios_base::in) == nullptr)
    this->setstate(ios_base::failbit);
}
#  endif

// extension
template <class _CharT, class _Traits>
inline basic_ifstream<_CharT, _Traits>::basic_ifstream(const string& __s, ios_base::openmode __mode)
    : … { … }

template <class _CharT, class _Traits>
inline basic_ifstream<_CharT, _Traits>::basic_ifstream(basic_ifstream&& __rhs)
    : … { … }

template <class _CharT, class _Traits>
inline basic_ifstream<_CharT, _Traits>& basic_ifstream<_CharT, _Traits>::operator=(basic_ifstream&& __rhs) { … }

template <class _CharT, class _Traits>
inline void basic_ifstream<_CharT, _Traits>::swap(basic_ifstream& __rhs) { … }

template <class _CharT, class _Traits>
inline _LIBCPP_HIDE_FROM_ABI void swap(basic_ifstream<_CharT, _Traits>& __x, basic_ifstream<_CharT, _Traits>& __y) { … }

template <class _CharT, class _Traits>
inline basic_filebuf<_CharT, _Traits>* basic_ifstream<_CharT, _Traits>::rdbuf() const { … }

template <class _CharT, class _Traits>
inline bool basic_ifstream<_CharT, _Traits>::is_open() const { … }

template <class _CharT, class _Traits>
void basic_ifstream<_CharT, _Traits>::open(const char* __s, ios_base::openmode __mode) { … }

#  ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
template <class _CharT, class _Traits>
void basic_ifstream<_CharT, _Traits>::open(const wchar_t* __s, ios_base::openmode __mode) {
  if (__sb_.open(__s, __mode | ios_base::in))
    this->clear();
  else
    this->setstate(ios_base::failbit);
}
#  endif

template <class _CharT, class _Traits>
void basic_ifstream<_CharT, _Traits>::open(const string& __s, ios_base::openmode __mode) { … }

template <class _CharT, class _Traits>
inline void basic_ifstream<_CharT, _Traits>::__open(int __fd, ios_base::openmode __mode) { … }

template <class _CharT, class _Traits>
inline void basic_ifstream<_CharT, _Traits>::close() { … }

// basic_ofstream

template <class _CharT, class _Traits>
class _LIBCPP_TEMPLATE_VIS basic_ofstream : public basic_ostream<_CharT, _Traits> { … };

template <class _CharT, class _Traits>
inline basic_ofstream<_CharT, _Traits>::basic_ofstream()
    : … { … }

template <class _CharT, class _Traits>
inline basic_ofstream<_CharT, _Traits>::basic_ofstream(const char* __s, ios_base::openmode __mode)
    : … { … }

#  ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
template <class _CharT, class _Traits>
inline basic_ofstream<_CharT, _Traits>::basic_ofstream(const wchar_t* __s, ios_base::openmode __mode)
    : basic_ostream<char_type, traits_type>(std::addressof(__sb_)) {
  if (__sb_.open(__s, __mode | ios_base::out) == nullptr)
    this->setstate(ios_base::failbit);
}
#  endif

// extension
template <class _CharT, class _Traits>
inline basic_ofstream<_CharT, _Traits>::basic_ofstream(const string& __s, ios_base::openmode __mode)
    : … { … }

template <class _CharT, class _Traits>
inline basic_ofstream<_CharT, _Traits>::basic_ofstream(basic_ofstream&& __rhs)
    : … { … }

template <class _CharT, class _Traits>
inline basic_ofstream<_CharT, _Traits>& basic_ofstream<_CharT, _Traits>::operator=(basic_ofstream&& __rhs) { … }

template <class _CharT, class _Traits>
inline void basic_ofstream<_CharT, _Traits>::swap(basic_ofstream& __rhs) { … }

template <class _CharT, class _Traits>
inline _LIBCPP_HIDE_FROM_ABI void swap(basic_ofstream<_CharT, _Traits>& __x, basic_ofstream<_CharT, _Traits>& __y) { … }

template <class _CharT, class _Traits>
inline basic_filebuf<_CharT, _Traits>* basic_ofstream<_CharT, _Traits>::rdbuf() const { … }

template <class _CharT, class _Traits>
inline bool basic_ofstream<_CharT, _Traits>::is_open() const { … }

template <class _CharT, class _Traits>
void basic_ofstream<_CharT, _Traits>::open(const char* __s, ios_base::openmode __mode) { … }

#  ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
template <class _CharT, class _Traits>
void basic_ofstream<_CharT, _Traits>::open(const wchar_t* __s, ios_base::openmode __mode) {
  if (__sb_.open(__s, __mode | ios_base::out))
    this->clear();
  else
    this->setstate(ios_base::failbit);
}
#  endif

template <class _CharT, class _Traits>
void basic_ofstream<_CharT, _Traits>::open(const string& __s, ios_base::openmode __mode) { … }

template <class _CharT, class _Traits>
inline void basic_ofstream<_CharT, _Traits>::__open(int __fd, ios_base::openmode __mode) { … }

template <class _CharT, class _Traits>
inline void basic_ofstream<_CharT, _Traits>::close() { … }

// basic_fstream

template <class _CharT, class _Traits>
class _LIBCPP_TEMPLATE_VIS basic_fstream : public basic_iostream<_CharT, _Traits> { … };

template <class _CharT, class _Traits>
inline basic_fstream<_CharT, _Traits>::basic_fstream()
    : … { … }

template <class _CharT, class _Traits>
inline basic_fstream<_CharT, _Traits>::basic_fstream(const char* __s, ios_base::openmode __mode)
    : … { … }

#  ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
template <class _CharT, class _Traits>
inline basic_fstream<_CharT, _Traits>::basic_fstream(const wchar_t* __s, ios_base::openmode __mode)
    : basic_iostream<char_type, traits_type>(std::addressof(__sb_)) {
  if (__sb_.open(__s, __mode) == nullptr)
    this->setstate(ios_base::failbit);
}
#  endif

template <class _CharT, class _Traits>
inline basic_fstream<_CharT, _Traits>::basic_fstream(const string& __s, ios_base::openmode __mode)
    : … { … }

// extension
template <class _CharT, class _Traits>
inline basic_fstream<_CharT, _Traits>::basic_fstream(basic_fstream&& __rhs)
    : … { … }

template <class _CharT, class _Traits>
inline basic_fstream<_CharT, _Traits>& basic_fstream<_CharT, _Traits>::operator=(basic_fstream&& __rhs) { … }

template <class _CharT, class _Traits>
inline void basic_fstream<_CharT, _Traits>::swap(basic_fstream& __rhs) { … }

template <class _CharT, class _Traits>
inline _LIBCPP_HIDE_FROM_ABI void swap(basic_fstream<_CharT, _Traits>& __x, basic_fstream<_CharT, _Traits>& __y) { … }

template <class _CharT, class _Traits>
inline basic_filebuf<_CharT, _Traits>* basic_fstream<_CharT, _Traits>::rdbuf() const { … }

template <class _CharT, class _Traits>
inline bool basic_fstream<_CharT, _Traits>::is_open() const { … }

template <class _CharT, class _Traits>
void basic_fstream<_CharT, _Traits>::open(const char* __s, ios_base::openmode __mode) { … }

#  ifdef _LIBCPP_HAS_OPEN_WITH_WCHAR
template <class _CharT, class _Traits>
void basic_fstream<_CharT, _Traits>::open(const wchar_t* __s, ios_base::openmode __mode) {
  if (__sb_.open(__s, __mode))
    this->clear();
  else
    this->setstate(ios_base::failbit);
}
#  endif

template <class _CharT, class _Traits>
void basic_fstream<_CharT, _Traits>::open(const string& __s, ios_base::openmode __mode) { … }

template <class _CharT, class _Traits>
inline void basic_fstream<_CharT, _Traits>::close() { … }

#  if _LIBCPP_AVAILABILITY_HAS_ADDITIONAL_IOSTREAM_EXPLICIT_INSTANTIATIONS_1
extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_ifstream<char>;
extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_ofstream<char>;
extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_filebuf<char>;
#  endif

_LIBCPP_END_NAMESPACE_STD

#endif // _LIBCPP_HAS_NO_FILESYSTEM

_LIBCPP_POP_MACROS

#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
#  include <atomic>
#  include <concepts>
#  include <cstdlib>
#  include <iosfwd>
#  include <limits>
#  include <mutex>
#  include <new>
#  include <stdexcept>
#  include <type_traits>
#endif

#endif // _LIBCPP_FSTREAM