xref: /freebsd/contrib/llvm-project/libcxx/include/fstream (revision 9c77fb6aaa366cbabc80ee1b834bcfe4df135491)
1// -*- C++ -*-
2//===----------------------------------------------------------------------===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef _LIBCPP_FSTREAM
11#define _LIBCPP_FSTREAM
12
13/*
14    fstream synopsis
15
16template <class charT, class traits = char_traits<charT> >
17class basic_filebuf
18    : public basic_streambuf<charT, traits>
19{
20public:
21    typedef charT                          char_type;
22    typedef traits                         traits_type;
23    typedef typename traits_type::int_type int_type;
24    typedef typename traits_type::pos_type pos_type;
25    typedef typename traits_type::off_type off_type;
26
27    // 27.9.1.2 Constructors/destructor:
28    basic_filebuf();
29    basic_filebuf(basic_filebuf&& rhs);
30    virtual ~basic_filebuf();
31
32    // 27.9.1.3 Assign/swap:
33    basic_filebuf& operator=(basic_filebuf&& rhs);
34    void swap(basic_filebuf& rhs);
35
36    // 27.9.1.4 Members:
37    bool is_open() const;
38    basic_filebuf* open(const char* s, ios_base::openmode mode);
39    basic_filebuf* open(const string& s, ios_base::openmode mode);
40    basic_filebuf* open(const filesystem::path& p, ios_base::openmode mode); // C++17
41    basic_filebuf* close();
42
43protected:
44    // 27.9.1.5 Overridden virtual functions:
45    virtual streamsize showmanyc();
46    virtual int_type underflow();
47    virtual int_type uflow();
48    virtual int_type pbackfail(int_type c = traits_type::eof());
49    virtual int_type overflow (int_type c = traits_type::eof());
50    virtual basic_streambuf<char_type, traits_type>* setbuf(char_type* s, streamsize n);
51    virtual pos_type seekoff(off_type off, ios_base::seekdir way,
52                             ios_base::openmode which = ios_base::in | ios_base::out);
53    virtual pos_type seekpos(pos_type sp,
54                             ios_base::openmode which = ios_base::in | ios_base::out);
55    virtual int sync();
56    virtual void imbue(const locale& loc);
57};
58
59template <class charT, class traits>
60  void
61  swap(basic_filebuf<charT, traits>& x, basic_filebuf<charT, traits>& y);
62
63typedef basic_filebuf<char>    filebuf;
64typedef basic_filebuf<wchar_t> wfilebuf;
65
66template <class charT, class traits = char_traits<charT> >
67class basic_ifstream
68    : public basic_istream<charT,traits>
69{
70public:
71    typedef charT                          char_type;
72    typedef traits                         traits_type;
73    typedef typename traits_type::int_type int_type;
74    typedef typename traits_type::pos_type pos_type;
75    typedef typename traits_type::off_type off_type;
76    using native_handle_type = typename basic_filebuf<charT, traits>::native_handle_type; // Since C++26
77
78    basic_ifstream();
79    explicit basic_ifstream(const char* s, ios_base::openmode mode = ios_base::in);
80    explicit basic_ifstream(const string& s, ios_base::openmode mode = ios_base::in);
81    template<class T>
82    explicit basic_ifstream(const T& s, ios_base::openmode mode = ios_base::in); // Since C++17
83    basic_ifstream(basic_ifstream&& rhs);
84
85    basic_ifstream& operator=(basic_ifstream&& rhs);
86    void swap(basic_ifstream& rhs);
87
88    basic_filebuf<char_type, traits_type>* rdbuf() const;
89    native_handle_type native_handle() const noexcept; // Since C++26
90    bool is_open() const;
91    void open(const char* s, ios_base::openmode mode = ios_base::in);
92    void open(const string& s, ios_base::openmode mode = ios_base::in);
93    void open(const filesystem::path& s, ios_base::openmode mode = ios_base::in); // C++17
94
95    void close();
96};
97
98template <class charT, class traits>
99  void
100  swap(basic_ifstream<charT, traits>& x, basic_ifstream<charT, traits>& y);
101
102typedef basic_ifstream<char>    ifstream;
103typedef basic_ifstream<wchar_t> wifstream;
104
105template <class charT, class traits = char_traits<charT> >
106class basic_ofstream
107    : public basic_ostream<charT,traits>
108{
109public:
110    typedef charT                          char_type;
111    typedef traits                         traits_type;
112    typedef typename traits_type::int_type int_type;
113    typedef typename traits_type::pos_type pos_type;
114    typedef typename traits_type::off_type off_type;
115    using native_handle_type = typename basic_filebuf<charT, traits>::native_handle_type; // Since C++26
116
117    basic_ofstream();
118    explicit basic_ofstream(const char* s, ios_base::openmode mode = ios_base::out);
119    explicit basic_ofstream(const string& s, ios_base::openmode mode = ios_base::out);
120    template<class T>
121    explicit basic_ofstream(const T& s, ios_base::openmode mode = ios_base::out); // Since C++17
122    basic_ofstream(basic_ofstream&& rhs);
123
124    basic_ofstream& operator=(basic_ofstream&& rhs);
125    void swap(basic_ofstream& rhs);
126
127    basic_filebuf<char_type, traits_type>* rdbuf() const;
128    native_handle_type native_handle() const noexcept; // Since C++26
129
130    bool is_open() const;
131    void open(const char* s, ios_base::openmode mode = ios_base::out);
132    void open(const string& s, ios_base::openmode mode = ios_base::out);
133    void open(const filesystem::path& p,
134              ios_base::openmode mode = ios_base::out); // C++17
135
136    void close();
137};
138
139template <class charT, class traits>
140  void
141  swap(basic_ofstream<charT, traits>& x, basic_ofstream<charT, traits>& y);
142
143typedef basic_ofstream<char>    ofstream;
144typedef basic_ofstream<wchar_t> wofstream;
145
146template <class charT, class traits=char_traits<charT> >
147class basic_fstream
148    : public basic_iostream<charT,traits>
149{
150public:
151    typedef charT                          char_type;
152    typedef traits                         traits_type;
153    typedef typename traits_type::int_type int_type;
154    typedef typename traits_type::pos_type pos_type;
155    typedef typename traits_type::off_type off_type;
156    using native_handle_type = typename basic_filebuf<charT, traits>::native_handle_type; // Since C++26
157
158    basic_fstream();
159    explicit basic_fstream(const char* s, ios_base::openmode mode = ios_base::in|ios_base::out);
160    explicit basic_fstream(const string& s, ios_base::openmode mode = ios_base::in|ios_base::out);
161    template<class T>
162    explicit basic_fstream(const T& s, ios_base::openmode mode = ios_base::in | ios_base::out); // Since C++17
163    basic_fstream(basic_fstream&& rhs);
164
165    basic_fstream& operator=(basic_fstream&& rhs);
166    void swap(basic_fstream& rhs);
167
168    basic_filebuf<char_type, traits_type>* rdbuf() const;
169    native_handle_type native_handle() const noexcept; // Since C++26
170    bool is_open() const;
171    void open(const char* s, ios_base::openmode mode = ios_base::in|ios_base::out);
172    void open(const string& s, ios_base::openmode mode = ios_base::in|ios_base::out);
173    void open(const filesystem::path& s,
174              ios_base::openmode mode = ios_base::in|ios_base::out); // C++17
175
176    void close();
177};
178
179template <class charT, class traits>
180  void swap(basic_fstream<charT, traits>& x, basic_fstream<charT, traits>& y);
181
182typedef basic_fstream<char>    fstream;
183typedef basic_fstream<wchar_t> wfstream;
184
185}  // std
186
187*/
188
189#if __cplusplus < 201103L && defined(_LIBCPP_USE_FROZEN_CXX03_HEADERS)
190#  include <__cxx03/fstream>
191#else
192#  include <__config>
193
194#  if _LIBCPP_HAS_FILESYSTEM && _LIBCPP_HAS_LOCALIZATION
195
196#    include <__algorithm/max.h>
197#    include <__assert>
198#    include <__filesystem/path.h>
199#    include <__fwd/fstream.h>
200#    include <__locale>
201#    include <__memory/addressof.h>
202#    include <__memory/unique_ptr.h>
203#    include <__ostream/basic_ostream.h>
204#    include <__type_traits/enable_if.h>
205#    include <__type_traits/is_same.h>
206#    include <__utility/move.h>
207#    include <__utility/swap.h>
208#    include <__utility/unreachable.h>
209#    include <cstdio>
210#    include <istream>
211#    include <streambuf>
212#    include <typeinfo>
213#    include <version>
214
215#    if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
216#      pragma GCC system_header
217#    endif
218
219_LIBCPP_PUSH_MACROS
220#    include <__undef_macros>
221
222_LIBCPP_BEGIN_NAMESPACE_STD
223
224#    if _LIBCPP_STD_VER >= 26 && defined(_LIBCPP_WIN32API)
225_LIBCPP_EXPORTED_FROM_ABI void* __filebuf_windows_native_handle(FILE* __file) noexcept;
226#    endif
227
228template <class _CharT, class _Traits>
229class basic_filebuf : public basic_streambuf<_CharT, _Traits> {
230public:
231  typedef _CharT char_type;
232  typedef _Traits traits_type;
233  typedef typename traits_type::int_type int_type;
234  typedef typename traits_type::pos_type pos_type;
235  typedef typename traits_type::off_type off_type;
236  typedef typename traits_type::state_type state_type;
237#    if _LIBCPP_STD_VER >= 26
238#      if defined(_LIBCPP_WIN32API)
239  using native_handle_type = void*; // HANDLE
240#      elif __has_include(<unistd.h>)
241  using native_handle_type = int; // POSIX file descriptor
242#      else
243#        error "Provide a native file handle!"
244#      endif
245#    endif
246
247  // 27.9.1.2 Constructors/destructor:
248  basic_filebuf();
249  basic_filebuf(basic_filebuf&& __rhs);
250  ~basic_filebuf() override;
251
252  // 27.9.1.3 Assign/swap:
253  _LIBCPP_HIDE_FROM_ABI basic_filebuf& operator=(basic_filebuf&& __rhs);
254  void swap(basic_filebuf& __rhs);
255
256  // 27.9.1.4 Members:
257  _LIBCPP_HIDE_FROM_ABI bool is_open() const;
258  basic_filebuf* open(const char* __s, ios_base::openmode __mode);
259#    if _LIBCPP_HAS_OPEN_WITH_WCHAR
260  basic_filebuf* open(const wchar_t* __s, ios_base::openmode __mode);
261#    endif
262  _LIBCPP_HIDE_FROM_ABI basic_filebuf* open(const string& __s, ios_base::openmode __mode);
263
264#    if _LIBCPP_STD_VER >= 17
265  _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY _LIBCPP_HIDE_FROM_ABI basic_filebuf*
266  open(const filesystem::path& __p, ios_base::openmode __mode) {
267    return open(__p.c_str(), __mode);
268  }
269#    endif
270  _LIBCPP_HIDE_FROM_ABI basic_filebuf* __open(int __fd, ios_base::openmode __mode);
271  basic_filebuf* close();
272#    if _LIBCPP_STD_VER >= 26
273  _LIBCPP_HIDE_FROM_ABI native_handle_type native_handle() const noexcept {
274    _LIBCPP_ASSERT_UNCATEGORIZED(this->is_open(), "File must be opened");
275#      if defined(_LIBCPP_WIN32API)
276    return std::__filebuf_windows_native_handle(__file_);
277#      elif __has_include(<unistd.h>)
278    return fileno(__file_);
279#      else
280#        error "Provide a way to determine the file native handle!"
281#      endif
282  }
283#    endif //  _LIBCPP_STD_VER >= 26
284
285  _LIBCPP_HIDE_FROM_ABI inline static const char* __make_mdstring(ios_base::openmode __mode) _NOEXCEPT;
286#    if _LIBCPP_HAS_OPEN_WITH_WCHAR
287  _LIBCPP_HIDE_FROM_ABI inline static const wchar_t* __make_mdwstring(ios_base::openmode __mode) _NOEXCEPT;
288#    endif
289
290protected:
291  // 27.9.1.5 Overridden virtual functions:
292  int_type underflow() override;
293  int_type pbackfail(int_type __c = traits_type::eof()) override;
294  int_type overflow(int_type __c = traits_type::eof()) override;
295  basic_streambuf<char_type, traits_type>* setbuf(char_type* __s, streamsize __n) override;
296  pos_type
297  seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __wch = ios_base::in | ios_base::out) override;
298  pos_type seekpos(pos_type __sp, ios_base::openmode __wch = ios_base::in | ios_base::out) override;
299  int sync() override;
300  void imbue(const locale& __loc) override;
301
302private:
303  char* __extbuf_;
304  const char* __extbufnext_;
305  const char* __extbufend_;
306  char __extbuf_min_[8];
307  size_t __ebs_;
308  char_type* __intbuf_;
309  size_t __ibs_;
310  FILE* __file_;
311  const codecvt<char_type, char, state_type>* __cv_;
312  state_type __st_;
313  state_type __st_last_;
314  ios_base::openmode __om_;
315  // There have been no file operations yet, which allows setting unbuffered
316  // I/O mode.
317  static const ios_base::openmode __no_io_operations = ios_base::trunc;
318  // Unbuffered I/O mode has been requested.
319  static const ios_base::openmode __use_unbuffered_io = ios_base::ate;
320  // Used to track the currently used mode and track whether the output should
321  // be unbuffered.
322  // [filebuf.virtuals]/12
323  //   If setbuf(0, 0) is called on a stream before any I/O has occurred on
324  //   that stream, the stream becomes unbuffered. Otherwise the results are
325  //   implementation-defined.
326  // This allows calling setbuf(0, 0)
327  // - before opening a file,
328  // - after opening a file, before
329  //   - a read
330  //   - a write
331  //   - a seek.
332  // Note that opening a file with ios_base::ate does a seek operation.
333  // Normally underflow, overflow, and sync change this flag to ios_base::in,
334  // ios_base_out, or 0.
335  //
336  // The ios_base::trunc and ios_base::ate flags are not used in __cm_. They
337  // are used to track the state of the unbuffered request. For readability
338  // they have the aliases __no_io_operations and __use_unbuffered_io
339  // respectively.
340  //
341  // The __no_io_operations and __use_unbuffered_io flags are used in the
342  // following way:
343  // - __no_io_operations is set upon construction to indicate the unbuffered
344  //   state can be set.
345  // - When requesting unbuffered output:
346  //   - If the file is open it sets the mode.
347  //   - Else places a request by adding the __use_unbuffered_io flag.
348  // - When a file is opened it checks whether both __no_io_operations and
349  //   __use_unbuffered_io are set. If so switches to unbuffered mode.
350  // - All file I/O operations change the mode effectively clearing the
351  //   __no_io_operations and __use_unbuffered_io flags.
352  ios_base::openmode __cm_;
353  bool __owns_eb_;
354  bool __owns_ib_;
355  bool __always_noconv_;
356
357  bool __read_mode();
358  void __write_mode();
359
360  _LIBCPP_HIDE_FROM_ABI static int __fseek(FILE* __file, pos_type __offset, int __whence);
361  _LIBCPP_HIDE_FROM_ABI static pos_type __ftell(FILE* __file);
362
363  _LIBCPP_EXPORTED_FROM_ABI friend FILE* __get_ostream_file(ostream&);
364
365  // There are multiple (__)open function, they use different C-API open
366  // function. After that call these functions behave the same. This function
367  // does that part and determines the final return value.
368  _LIBCPP_HIDE_FROM_ABI basic_filebuf* __do_open(FILE* __file, ios_base::openmode __mode) {
369    __file_ = __file;
370    if (!__file_)
371      return nullptr;
372
373    __om_ = __mode;
374    if (__cm_ == (__no_io_operations | __use_unbuffered_io)) {
375      std::setbuf(__file_, nullptr);
376      __cm_ = 0;
377    }
378
379    if (__mode & ios_base::ate) {
380      __cm_ = 0;
381      if (fseek(__file_, 0, SEEK_END)) {
382        fclose(__file_);
383        __file_ = nullptr;
384        return nullptr;
385      }
386    }
387
388    return this;
389  }
390
391  // If the file is already open, switch to unbuffered mode. Otherwise, record
392  // the request to use unbuffered mode so that we use that mode when we
393  // eventually open the file.
394  _LIBCPP_HIDE_FROM_ABI void __request_unbuffered_mode(char_type* __s, streamsize __n) {
395    if (__cm_ == __no_io_operations && __s == nullptr && __n == 0) {
396      if (__file_) {
397        std::setbuf(__file_, nullptr);
398        __cm_ = 0;
399      } else {
400        __cm_ = __no_io_operations | __use_unbuffered_io;
401      }
402    }
403  }
404
405  _LIBCPP_HIDE_FROM_ABI typename traits_type::int_type __overflow_failed() {
406    if (this->pptr() == this->epptr() + 1) {
407      this->pbump(-1); // lose the character we overflowed above -- we don't really have a
408                       // choice since we couldn't commit the contents of the put area
409    }
410    return traits_type::eof();
411  }
412};
413
414template <class _CharT, class _Traits>
415basic_filebuf<_CharT, _Traits>::basic_filebuf()
416    : __extbuf_(nullptr),
417      __extbufnext_(nullptr),
418      __extbufend_(nullptr),
419      __ebs_(0),
420      __intbuf_(nullptr),
421      __ibs_(0),
422      __file_(nullptr),
423      __cv_(nullptr),
424      __st_(),
425      __st_last_(),
426      __om_(0),
427      __cm_(__no_io_operations),
428      __owns_eb_(false),
429      __owns_ib_(false),
430      __always_noconv_(false) {
431  if (std::has_facet<codecvt<char_type, char, state_type> >(this->getloc())) {
432    __cv_            = std::addressof(std::use_facet<codecvt<char_type, char, state_type> >(this->getloc()));
433    __always_noconv_ = __cv_->always_noconv();
434  }
435  setbuf(nullptr, 4096);
436}
437
438template <class _CharT, class _Traits>
439basic_filebuf<_CharT, _Traits>::basic_filebuf(basic_filebuf&& __rhs) : basic_streambuf<_CharT, _Traits>(__rhs) {
440  if (__rhs.__extbuf_ == __rhs.__extbuf_min_) {
441    __extbuf_     = __extbuf_min_;
442    __extbufnext_ = __extbuf_ + (__rhs.__extbufnext_ - __rhs.__extbuf_);
443    __extbufend_  = __extbuf_ + (__rhs.__extbufend_ - __rhs.__extbuf_);
444  } else {
445    __extbuf_     = __rhs.__extbuf_;
446    __extbufnext_ = __rhs.__extbufnext_;
447    __extbufend_  = __rhs.__extbufend_;
448  }
449  __ebs_           = __rhs.__ebs_;
450  __intbuf_        = __rhs.__intbuf_;
451  __ibs_           = __rhs.__ibs_;
452  __file_          = __rhs.__file_;
453  __cv_            = __rhs.__cv_;
454  __st_            = __rhs.__st_;
455  __st_last_       = __rhs.__st_last_;
456  __om_            = __rhs.__om_;
457  __cm_            = __rhs.__cm_;
458  __owns_eb_       = __rhs.__owns_eb_;
459  __owns_ib_       = __rhs.__owns_ib_;
460  __always_noconv_ = __rhs.__always_noconv_;
461  if (__rhs.pbase()) {
462    if (__rhs.pbase() == __rhs.__intbuf_)
463      this->setp(__intbuf_, __intbuf_ + (__rhs.epptr() - __rhs.pbase()));
464    else
465      this->setp((char_type*)__extbuf_, (char_type*)__extbuf_ + (__rhs.epptr() - __rhs.pbase()));
466    this->__pbump(__rhs.pptr() - __rhs.pbase());
467  } else if (__rhs.eback()) {
468    if (__rhs.eback() == __rhs.__intbuf_)
469      this->setg(__intbuf_, __intbuf_ + (__rhs.gptr() - __rhs.eback()), __intbuf_ + (__rhs.egptr() - __rhs.eback()));
470    else
471      this->setg((char_type*)__extbuf_,
472                 (char_type*)__extbuf_ + (__rhs.gptr() - __rhs.eback()),
473                 (char_type*)__extbuf_ + (__rhs.egptr() - __rhs.eback()));
474  }
475  __rhs.__extbuf_     = nullptr;
476  __rhs.__extbufnext_ = nullptr;
477  __rhs.__extbufend_  = nullptr;
478  __rhs.__ebs_        = 0;
479  __rhs.__intbuf_     = 0;
480  __rhs.__ibs_        = 0;
481  __rhs.__file_       = nullptr;
482  __rhs.__st_         = state_type();
483  __rhs.__st_last_    = state_type();
484  __rhs.__om_         = 0;
485  __rhs.__cm_         = 0;
486  __rhs.__owns_eb_    = false;
487  __rhs.__owns_ib_    = false;
488  __rhs.setg(0, 0, 0);
489  __rhs.setp(0, 0);
490}
491
492template <class _CharT, class _Traits>
493inline basic_filebuf<_CharT, _Traits>& basic_filebuf<_CharT, _Traits>::operator=(basic_filebuf&& __rhs) {
494  close();
495  swap(__rhs);
496  return *this;
497}
498
499template <class _CharT, class _Traits>
500basic_filebuf<_CharT, _Traits>::~basic_filebuf() {
501#    if _LIBCPP_HAS_EXCEPTIONS
502  try {
503#    endif // _LIBCPP_HAS_EXCEPTIONS
504    close();
505#    if _LIBCPP_HAS_EXCEPTIONS
506  } catch (...) {
507  }
508#    endif // _LIBCPP_HAS_EXCEPTIONS
509  if (__owns_eb_)
510    delete[] __extbuf_;
511  if (__owns_ib_)
512    delete[] __intbuf_;
513}
514
515template <class _CharT, class _Traits>
516void basic_filebuf<_CharT, _Traits>::swap(basic_filebuf& __rhs) {
517  basic_streambuf<char_type, traits_type>::swap(__rhs);
518  if (__extbuf_ != __extbuf_min_ && __rhs.__extbuf_ != __rhs.__extbuf_min_) {
519    // Neither *this nor __rhs uses the small buffer, so we can simply swap the pointers.
520    std::swap(__extbuf_, __rhs.__extbuf_);
521    std::swap(__extbufnext_, __rhs.__extbufnext_);
522    std::swap(__extbufend_, __rhs.__extbufend_);
523  } else {
524    ptrdiff_t __ln = __extbufnext_ ? __extbufnext_ - __extbuf_ : 0;
525    ptrdiff_t __le = __extbufend_ ? __extbufend_ - __extbuf_ : 0;
526    ptrdiff_t __rn = __rhs.__extbufnext_ ? __rhs.__extbufnext_ - __rhs.__extbuf_ : 0;
527    ptrdiff_t __re = __rhs.__extbufend_ ? __rhs.__extbufend_ - __rhs.__extbuf_ : 0;
528    if (__extbuf_ == __extbuf_min_ && __rhs.__extbuf_ != __rhs.__extbuf_min_) {
529      // *this uses the small buffer, but __rhs doesn't.
530      __extbuf_       = __rhs.__extbuf_;
531      __rhs.__extbuf_ = __rhs.__extbuf_min_;
532      std::memmove(__rhs.__extbuf_min_, __extbuf_min_, sizeof(__extbuf_min_));
533    } else if (__extbuf_ != __extbuf_min_ && __rhs.__extbuf_ == __rhs.__extbuf_min_) {
534      // *this doesn't use the small buffer, but __rhs does.
535      __rhs.__extbuf_ = __extbuf_;
536      __extbuf_       = __extbuf_min_;
537      std::memmove(__extbuf_min_, __rhs.__extbuf_min_, sizeof(__extbuf_min_));
538    } else {
539      // Both *this and __rhs use the small buffer.
540      char __tmp[sizeof(__extbuf_min_)];
541      std::memmove(__tmp, __extbuf_min_, sizeof(__extbuf_min_));
542      std::memmove(__extbuf_min_, __rhs.__extbuf_min_, sizeof(__extbuf_min_));
543      std::memmove(__rhs.__extbuf_min_, __tmp, sizeof(__extbuf_min_));
544    }
545    __extbufnext_       = __extbuf_ + __rn;
546    __extbufend_        = __extbuf_ + __re;
547    __rhs.__extbufnext_ = __rhs.__extbuf_ + __ln;
548    __rhs.__extbufend_  = __rhs.__extbuf_ + __le;
549  }
550  std::swap(__ebs_, __rhs.__ebs_);
551  std::swap(__intbuf_, __rhs.__intbuf_);
552  std::swap(__ibs_, __rhs.__ibs_);
553  std::swap(__file_, __rhs.__file_);
554  std::swap(__cv_, __rhs.__cv_);
555  std::swap(__st_, __rhs.__st_);
556  std::swap(__st_last_, __rhs.__st_last_);
557  std::swap(__om_, __rhs.__om_);
558  std::swap(__cm_, __rhs.__cm_);
559  std::swap(__owns_eb_, __rhs.__owns_eb_);
560  std::swap(__owns_ib_, __rhs.__owns_ib_);
561  std::swap(__always_noconv_, __rhs.__always_noconv_);
562  if (this->eback() == (char_type*)__rhs.__extbuf_min_) {
563    ptrdiff_t __n = this->gptr() - this->eback();
564    ptrdiff_t __e = this->egptr() - this->eback();
565    this->setg((char_type*)__extbuf_min_, (char_type*)__extbuf_min_ + __n, (char_type*)__extbuf_min_ + __e);
566  } else if (this->pbase() == (char_type*)__rhs.__extbuf_min_) {
567    ptrdiff_t __n = this->pptr() - this->pbase();
568    ptrdiff_t __e = this->epptr() - this->pbase();
569    this->setp((char_type*)__extbuf_min_, (char_type*)__extbuf_min_ + __e);
570    this->__pbump(__n);
571  }
572  if (__rhs.eback() == (char_type*)__extbuf_min_) {
573    ptrdiff_t __n = __rhs.gptr() - __rhs.eback();
574    ptrdiff_t __e = __rhs.egptr() - __rhs.eback();
575    __rhs.setg(
576        (char_type*)__rhs.__extbuf_min_, (char_type*)__rhs.__extbuf_min_ + __n, (char_type*)__rhs.__extbuf_min_ + __e);
577  } else if (__rhs.pbase() == (char_type*)__extbuf_min_) {
578    ptrdiff_t __n = __rhs.pptr() - __rhs.pbase();
579    ptrdiff_t __e = __rhs.epptr() - __rhs.pbase();
580    __rhs.setp((char_type*)__rhs.__extbuf_min_, (char_type*)__rhs.__extbuf_min_ + __e);
581    __rhs.__pbump(__n);
582  }
583}
584
585template <class _CharT, class _Traits>
586inline _LIBCPP_HIDE_FROM_ABI void swap(basic_filebuf<_CharT, _Traits>& __x, basic_filebuf<_CharT, _Traits>& __y) {
587  __x.swap(__y);
588}
589
590template <class _CharT, class _Traits>
591inline bool basic_filebuf<_CharT, _Traits>::is_open() const {
592  return __file_ != nullptr;
593}
594
595template <class _CharT, class _Traits>
596const char* basic_filebuf<_CharT, _Traits>::__make_mdstring(ios_base::openmode __mode) _NOEXCEPT {
597  switch (__mode & ~ios_base::ate) {
598  case ios_base::out:
599  case ios_base::out | ios_base::trunc:
600    return "w" _LIBCPP_FOPEN_CLOEXEC_MODE;
601  case ios_base::out | ios_base::app:
602  case ios_base::app:
603    return "a" _LIBCPP_FOPEN_CLOEXEC_MODE;
604  case ios_base::in:
605    return "r" _LIBCPP_FOPEN_CLOEXEC_MODE;
606  case ios_base::in | ios_base::out:
607    return "r+" _LIBCPP_FOPEN_CLOEXEC_MODE;
608  case ios_base::in | ios_base::out | ios_base::trunc:
609    return "w+" _LIBCPP_FOPEN_CLOEXEC_MODE;
610  case ios_base::in | ios_base::out | ios_base::app:
611  case ios_base::in | ios_base::app:
612    return "a+" _LIBCPP_FOPEN_CLOEXEC_MODE;
613  case ios_base::out | ios_base::binary:
614  case ios_base::out | ios_base::trunc | ios_base::binary:
615    return "wb" _LIBCPP_FOPEN_CLOEXEC_MODE;
616  case ios_base::out | ios_base::app | ios_base::binary:
617  case ios_base::app | ios_base::binary:
618    return "ab" _LIBCPP_FOPEN_CLOEXEC_MODE;
619  case ios_base::in | ios_base::binary:
620    return "rb" _LIBCPP_FOPEN_CLOEXEC_MODE;
621  case ios_base::in | ios_base::out | ios_base::binary:
622    return "r+b" _LIBCPP_FOPEN_CLOEXEC_MODE;
623  case ios_base::in | ios_base::out | ios_base::trunc | ios_base::binary:
624    return "w+b" _LIBCPP_FOPEN_CLOEXEC_MODE;
625  case ios_base::in | ios_base::out | ios_base::app | ios_base::binary:
626  case ios_base::in | ios_base::app | ios_base::binary:
627    return "a+b" _LIBCPP_FOPEN_CLOEXEC_MODE;
628#    if _LIBCPP_STD_VER >= 23
629  case ios_base::out | ios_base::noreplace:
630  case ios_base::out | ios_base::trunc | ios_base::noreplace:
631    return "wx" _LIBCPP_FOPEN_CLOEXEC_MODE;
632  case ios_base::in | ios_base::out | ios_base::trunc | ios_base::noreplace:
633    return "w+x" _LIBCPP_FOPEN_CLOEXEC_MODE;
634  case ios_base::out | ios_base::binary | ios_base::noreplace:
635  case ios_base::out | ios_base::trunc | ios_base::binary | ios_base::noreplace:
636    return "wbx" _LIBCPP_FOPEN_CLOEXEC_MODE;
637  case ios_base::in | ios_base::out | ios_base::trunc | ios_base::binary | ios_base::noreplace:
638    return "w+bx" _LIBCPP_FOPEN_CLOEXEC_MODE;
639#    endif // _LIBCPP_STD_VER >= 23
640  default:
641    return nullptr;
642  }
643  __libcpp_unreachable();
644}
645
646#    if _LIBCPP_HAS_OPEN_WITH_WCHAR
647template <class _CharT, class _Traits>
648const wchar_t* basic_filebuf<_CharT, _Traits>::__make_mdwstring(ios_base::openmode __mode) _NOEXCEPT {
649  switch (__mode & ~ios_base::ate) {
650  case ios_base::out:
651  case ios_base::out | ios_base::trunc:
652    return L"w";
653  case ios_base::out | ios_base::app:
654  case ios_base::app:
655    return L"a";
656  case ios_base::in:
657    return L"r";
658  case ios_base::in | ios_base::out:
659    return L"r+";
660  case ios_base::in | ios_base::out | ios_base::trunc:
661    return L"w+";
662  case ios_base::in | ios_base::out | ios_base::app:
663  case ios_base::in | ios_base::app:
664    return L"a+";
665  case ios_base::out | ios_base::binary:
666  case ios_base::out | ios_base::trunc | ios_base::binary:
667    return L"wb";
668  case ios_base::out | ios_base::app | ios_base::binary:
669  case ios_base::app | ios_base::binary:
670    return L"ab";
671  case ios_base::in | ios_base::binary:
672    return L"rb";
673  case ios_base::in | ios_base::out | ios_base::binary:
674    return L"r+b";
675  case ios_base::in | ios_base::out | ios_base::trunc | ios_base::binary:
676    return L"w+b";
677  case ios_base::in | ios_base::out | ios_base::app | ios_base::binary:
678  case ios_base::in | ios_base::app | ios_base::binary:
679    return L"a+b";
680#      if _LIBCPP_STD_VER >= 23
681  case ios_base::out | ios_base::noreplace:
682  case ios_base::out | ios_base::trunc | ios_base::noreplace:
683    return L"wx";
684  case ios_base::in | ios_base::out | ios_base::trunc | ios_base::noreplace:
685    return L"w+x";
686  case ios_base::out | ios_base::binary | ios_base::noreplace:
687  case ios_base::out | ios_base::trunc | ios_base::binary | ios_base::noreplace:
688    return L"wbx";
689  case ios_base::in | ios_base::out | ios_base::trunc | ios_base::binary | ios_base::noreplace:
690    return L"w+bx";
691#      endif // _LIBCPP_STD_VER >= 23
692  default:
693    return nullptr;
694  }
695  __libcpp_unreachable();
696}
697#    endif
698
699template <class _CharT, class _Traits>
700basic_filebuf<_CharT, _Traits>* basic_filebuf<_CharT, _Traits>::open(const char* __s, ios_base::openmode __mode) {
701  if (__file_)
702    return nullptr;
703  const char* __mdstr = __make_mdstring(__mode);
704  if (!__mdstr)
705    return nullptr;
706
707  return __do_open(std::fopen(__s, __mdstr), __mode);
708}
709
710template <class _CharT, class _Traits>
711inline basic_filebuf<_CharT, _Traits>* basic_filebuf<_CharT, _Traits>::__open(int __fd, ios_base::openmode __mode) {
712  if (__file_)
713    return nullptr;
714  const char* __mdstr = __make_mdstring(__mode);
715  if (!__mdstr)
716    return nullptr;
717
718  return __do_open(fdopen(__fd, __mdstr), __mode);
719}
720
721#    if _LIBCPP_HAS_OPEN_WITH_WCHAR
722// This is basically the same as the char* overload except that it uses _wfopen
723// and long mode strings.
724template <class _CharT, class _Traits>
725basic_filebuf<_CharT, _Traits>* basic_filebuf<_CharT, _Traits>::open(const wchar_t* __s, ios_base::openmode __mode) {
726  if (__file_)
727    return nullptr;
728  const wchar_t* __mdstr = __make_mdwstring(__mode);
729  if (!__mdstr)
730    return nullptr;
731
732  return __do_open(_wfopen(__s, __mdstr), __mode);
733}
734#    endif
735
736template <class _CharT, class _Traits>
737inline basic_filebuf<_CharT, _Traits>*
738basic_filebuf<_CharT, _Traits>::open(const string& __s, ios_base::openmode __mode) {
739  return open(__s.c_str(), __mode);
740}
741
742template <class _CharT, class _Traits>
743basic_filebuf<_CharT, _Traits>* basic_filebuf<_CharT, _Traits>::close() {
744  basic_filebuf<_CharT, _Traits>* __rt = nullptr;
745  if (__file_) {
746    __rt = this;
747    unique_ptr<FILE, int (*)(FILE*)> __h(__file_, fclose);
748    if (sync())
749      __rt = nullptr;
750    if (fclose(__h.release()))
751      __rt = nullptr;
752    __file_ = nullptr;
753    setbuf(0, 0);
754  }
755  return __rt;
756}
757
758template <class _CharT, class _Traits>
759typename basic_filebuf<_CharT, _Traits>::int_type basic_filebuf<_CharT, _Traits>::underflow() {
760  if (__file_ == nullptr)
761    return traits_type::eof();
762  bool __initial = __read_mode();
763  char_type __1buf;
764  if (this->gptr() == nullptr)
765    this->setg(std::addressof(__1buf), std::addressof(__1buf) + 1, std::addressof(__1buf) + 1);
766  const size_t __unget_sz = __initial ? 0 : std::min<size_t>((this->egptr() - this->eback()) / 2, 4);
767  int_type __c            = traits_type::eof();
768  if (this->gptr() == this->egptr()) {
769    std::memmove(this->eback(), this->egptr() - __unget_sz, __unget_sz * sizeof(char_type));
770    if (__always_noconv_) {
771      size_t __nmemb = static_cast<size_t>(this->egptr() - this->eback() - __unget_sz);
772      __nmemb        = std::fread(this->eback() + __unget_sz, 1, __nmemb, __file_);
773      if (__nmemb != 0) {
774        this->setg(this->eback(), this->eback() + __unget_sz, this->eback() + __unget_sz + __nmemb);
775        __c = traits_type::to_int_type(*this->gptr());
776      }
777    } else {
778      if (__extbufend_ != __extbufnext_) {
779        _LIBCPP_ASSERT_NON_NULL(__extbufnext_ != nullptr, "underflow moving from nullptr");
780        _LIBCPP_ASSERT_NON_NULL(__extbuf_ != nullptr, "underflow moving into nullptr");
781        std::memmove(__extbuf_, __extbufnext_, __extbufend_ - __extbufnext_);
782      }
783      __extbufnext_ = __extbuf_ + (__extbufend_ - __extbufnext_);
784      __extbufend_  = __extbuf_ + (__extbuf_ == __extbuf_min_ ? sizeof(__extbuf_min_) : __ebs_);
785      size_t __nmemb =
786          std::min(static_cast<size_t>(__ibs_ - __unget_sz), static_cast<size_t>(__extbufend_ - __extbufnext_));
787      codecvt_base::result __r;
788      __st_last_  = __st_;
789      size_t __nr = std::fread((void*)const_cast<char*>(__extbufnext_), 1, __nmemb, __file_);
790      if (__nr != 0) {
791        if (!__cv_)
792          std::__throw_bad_cast();
793
794        __extbufend_ = __extbufnext_ + __nr;
795        char_type* __inext;
796        __r = __cv_->in(
797            __st_, __extbuf_, __extbufend_, __extbufnext_, this->eback() + __unget_sz, this->eback() + __ibs_, __inext);
798        if (__r == codecvt_base::noconv) {
799          this->setg((char_type*)__extbuf_, (char_type*)__extbuf_, (char_type*)const_cast<char*>(__extbufend_));
800          __c = traits_type::to_int_type(*this->gptr());
801        } else if (__inext != this->eback() + __unget_sz) {
802          this->setg(this->eback(), this->eback() + __unget_sz, __inext);
803          __c = traits_type::to_int_type(*this->gptr());
804        }
805      }
806    }
807  } else
808    __c = traits_type::to_int_type(*this->gptr());
809  if (this->eback() == std::addressof(__1buf))
810    this->setg(nullptr, nullptr, nullptr);
811  return __c;
812}
813
814template <class _CharT, class _Traits>
815typename basic_filebuf<_CharT, _Traits>::int_type basic_filebuf<_CharT, _Traits>::pbackfail(int_type __c) {
816  if (__file_ && this->eback() < this->gptr()) {
817    if (traits_type::eq_int_type(__c, traits_type::eof())) {
818      this->gbump(-1);
819      return traits_type::not_eof(__c);
820    }
821    if ((__om_ & ios_base::out) || traits_type::eq(traits_type::to_char_type(__c), this->gptr()[-1])) {
822      this->gbump(-1);
823      *this->gptr() = traits_type::to_char_type(__c);
824      return __c;
825    }
826  }
827  return traits_type::eof();
828}
829
830template <class _CharT, class _Traits>
831typename basic_filebuf<_CharT, _Traits>::int_type basic_filebuf<_CharT, _Traits>::overflow(int_type __c) {
832  if (__file_ == nullptr)
833    return traits_type::eof();
834  __write_mode();
835  char_type __1buf;
836  char_type* __pb_save  = this->pbase();
837  char_type* __epb_save = this->epptr();
838  if (!traits_type::eq_int_type(__c, traits_type::eof())) {
839    if (this->pptr() == nullptr)
840      this->setp(std::addressof(__1buf), std::addressof(__1buf) + 1);
841    *this->pptr() = traits_type::to_char_type(__c);
842    this->pbump(1);
843  }
844
845  // There is nothing to write, early return
846  if (this->pptr() == this->pbase()) {
847    return traits_type::not_eof(__c);
848  }
849
850  if (__always_noconv_) {
851    size_t __n = static_cast<size_t>(this->pptr() - this->pbase());
852    if (std::fwrite(this->pbase(), sizeof(char_type), __n, __file_) != __n) {
853      return __overflow_failed();
854    }
855  } else {
856    if (!__cv_)
857      std::__throw_bad_cast();
858
859    // See [filebuf.virtuals]
860    char_type* __b = this->pbase();
861    char_type* __p = this->pptr();
862    const char_type* __end;
863    char* __extbuf_end = __extbuf_;
864    do {
865      codecvt_base::result __r = __cv_->out(__st_, __b, __p, __end, __extbuf_, __extbuf_ + __ebs_, __extbuf_end);
866      if (__end == __b) {
867        return __overflow_failed();
868      }
869
870      // No conversion needed: output characters directly to the file, done.
871      if (__r == codecvt_base::noconv) {
872        size_t __n = static_cast<size_t>(__p - __b);
873        if (std::fwrite(__b, 1, __n, __file_) != __n) {
874          return __overflow_failed();
875        }
876        break;
877
878        // Conversion successful: output the converted characters to the file, done.
879      } else if (__r == codecvt_base::ok) {
880        size_t __n = static_cast<size_t>(__extbuf_end - __extbuf_);
881        if (std::fwrite(__extbuf_, 1, __n, __file_) != __n) {
882          return __overflow_failed();
883        }
884        break;
885
886        // Conversion partially successful: output converted characters to the file and repeat with the
887        // remaining characters.
888      } else if (__r == codecvt_base::partial) {
889        size_t __n = static_cast<size_t>(__extbuf_end - __extbuf_);
890        if (std::fwrite(__extbuf_, 1, __n, __file_) != __n) {
891          return __overflow_failed();
892        }
893        __b = const_cast<char_type*>(__end);
894        continue;
895
896      } else {
897        return __overflow_failed();
898      }
899    } while (true);
900  }
901  this->setp(__pb_save, __epb_save);
902  return traits_type::not_eof(__c);
903}
904
905template <class _CharT, class _Traits>
906basic_streambuf<_CharT, _Traits>* basic_filebuf<_CharT, _Traits>::setbuf(char_type* __s, streamsize __n) {
907  this->setg(nullptr, nullptr, nullptr);
908  this->setp(nullptr, nullptr);
909  __request_unbuffered_mode(__s, __n);
910  if (__owns_eb_)
911    delete[] __extbuf_;
912  if (__owns_ib_)
913    delete[] __intbuf_;
914  __ebs_ = __n;
915  if (__ebs_ > sizeof(__extbuf_min_)) {
916    if (__always_noconv_ && __s) {
917      __extbuf_  = (char*)__s;
918      __owns_eb_ = false;
919    } else {
920      __extbuf_  = new char[__ebs_];
921      __owns_eb_ = true;
922    }
923  } else {
924    __extbuf_  = __extbuf_min_;
925    __ebs_     = sizeof(__extbuf_min_);
926    __owns_eb_ = false;
927  }
928  if (!__always_noconv_) {
929    __ibs_ = max<streamsize>(__n, sizeof(__extbuf_min_));
930    if (__s && __ibs_ > sizeof(__extbuf_min_)) {
931      __intbuf_  = __s;
932      __owns_ib_ = false;
933    } else {
934      __intbuf_  = new char_type[__ibs_];
935      __owns_ib_ = true;
936    }
937  } else {
938    __ibs_     = 0;
939    __intbuf_  = nullptr;
940    __owns_ib_ = false;
941  }
942  return this;
943}
944
945template <class _CharT, class _Traits>
946typename basic_filebuf<_CharT, _Traits>::pos_type
947basic_filebuf<_CharT, _Traits>::seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode) {
948  if (!__cv_)
949    std::__throw_bad_cast();
950
951  int __width = __cv_->encoding();
952  if (__file_ == nullptr || (__width <= 0 && __off != 0) || sync())
953    return pos_type(off_type(-1));
954  // __width > 0 || __off == 0
955  int __whence;
956  switch (__way) {
957  case ios_base::beg:
958    __whence = SEEK_SET;
959    break;
960  case ios_base::cur:
961    __whence = SEEK_CUR;
962    break;
963  case ios_base::end:
964    __whence = SEEK_END;
965    break;
966  default:
967    return pos_type(off_type(-1));
968  }
969  if (__fseek(__file_, __width > 0 ? __width * __off : 0, __whence))
970    return pos_type(off_type(-1));
971  pos_type __r = __ftell(__file_);
972  __r.state(__st_);
973  return __r;
974}
975
976template <class _CharT, class _Traits>
977int basic_filebuf<_CharT, _Traits>::__fseek(FILE* __file, pos_type __offset, int __whence) {
978#    if defined(_LIBCPP_MSVCRT_LIKE)
979  return _fseeki64(__file, __offset, __whence);
980#    elif defined(_NEWLIB_VERSION)
981  return fseek(__file, __offset, __whence);
982#    else
983  return ::fseeko(__file, __offset, __whence);
984#    endif
985}
986
987template <class _CharT, class _Traits>
988typename basic_filebuf<_CharT, _Traits>::pos_type basic_filebuf<_CharT, _Traits>::__ftell(FILE* __file) {
989#    if defined(_LIBCPP_MSVCRT_LIKE)
990  return _ftelli64(__file);
991#    elif defined(_NEWLIB_VERSION)
992  return ftell(__file);
993#    else
994  return ftello(__file);
995#    endif
996}
997
998template <class _CharT, class _Traits>
999typename basic_filebuf<_CharT, _Traits>::pos_type
1000basic_filebuf<_CharT, _Traits>::seekpos(pos_type __sp, ios_base::openmode) {
1001  if (__file_ == nullptr || sync())
1002    return pos_type(off_type(-1));
1003  if (__fseek(__file_, __sp, SEEK_SET))
1004    return pos_type(off_type(-1));
1005  __st_ = __sp.state();
1006  return __sp;
1007}
1008
1009template <class _CharT, class _Traits>
1010int basic_filebuf<_CharT, _Traits>::sync() {
1011  if (__file_ == nullptr)
1012    return 0;
1013  if (!__cv_)
1014    std::__throw_bad_cast();
1015
1016  if (__cm_ & ios_base::out) {
1017    if (this->pptr() != this->pbase())
1018      if (overflow() == traits_type::eof())
1019        return -1;
1020    codecvt_base::result __r;
1021    do {
1022      char* __extbe;
1023      __r            = __cv_->unshift(__st_, __extbuf_, __extbuf_ + __ebs_, __extbe);
1024      size_t __nmemb = static_cast<size_t>(__extbe - __extbuf_);
1025      if (std::fwrite(__extbuf_, 1, __nmemb, __file_) != __nmemb)
1026        return -1;
1027    } while (__r == codecvt_base::partial);
1028    if (__r == codecvt_base::error)
1029      return -1;
1030    if (std::fflush(__file_))
1031      return -1;
1032  } else if (__cm_ & ios_base::in) {
1033    off_type __c;
1034    state_type __state = __st_last_;
1035    bool __update_st   = false;
1036    if (__always_noconv_)
1037      __c = this->egptr() - this->gptr();
1038    else {
1039      int __width = __cv_->encoding();
1040      __c         = __extbufend_ - __extbufnext_;
1041      if (__width > 0)
1042        __c += __width * (this->egptr() - this->gptr());
1043      else {
1044        if (this->gptr() != this->egptr()) {
1045          const int __off = __cv_->length(__state, __extbuf_, __extbufnext_, this->gptr() - this->eback());
1046          __c += __extbufnext_ - __extbuf_ - __off;
1047          __update_st = true;
1048        }
1049      }
1050    }
1051    if (__fseek(__file_, -__c, SEEK_CUR))
1052      return -1;
1053    if (__update_st)
1054      __st_ = __state;
1055    __extbufnext_ = __extbufend_ = __extbuf_;
1056    this->setg(nullptr, nullptr, nullptr);
1057    __cm_ = 0;
1058  }
1059  return 0;
1060}
1061
1062template <class _CharT, class _Traits>
1063void basic_filebuf<_CharT, _Traits>::imbue(const locale& __loc) {
1064  sync();
1065  __cv_            = std::addressof(std::use_facet<codecvt<char_type, char, state_type> >(__loc));
1066  bool __old_anc   = __always_noconv_;
1067  __always_noconv_ = __cv_->always_noconv();
1068  if (__old_anc != __always_noconv_) {
1069    this->setg(nullptr, nullptr, nullptr);
1070    this->setp(nullptr, nullptr);
1071    // invariant, char_type is char, else we couldn't get here
1072    if (__always_noconv_) // need to dump __intbuf_
1073    {
1074      if (__owns_eb_)
1075        delete[] __extbuf_;
1076      __owns_eb_ = __owns_ib_;
1077      __ebs_     = __ibs_;
1078      __extbuf_  = (char*)__intbuf_;
1079      __ibs_     = 0;
1080      __intbuf_  = nullptr;
1081      __owns_ib_ = false;
1082    } else // need to obtain an __intbuf_.
1083    {      // If __extbuf_ is user-supplied, use it, else new __intbuf_
1084      if (!__owns_eb_ && __extbuf_ != __extbuf_min_) {
1085        __ibs_     = __ebs_;
1086        __intbuf_  = (char_type*)__extbuf_;
1087        __owns_ib_ = false;
1088        __extbuf_  = new char[__ebs_];
1089        __owns_eb_ = true;
1090      } else {
1091        __ibs_     = __ebs_;
1092        __intbuf_  = new char_type[__ibs_];
1093        __owns_ib_ = true;
1094      }
1095    }
1096  }
1097}
1098
1099template <class _CharT, class _Traits>
1100bool basic_filebuf<_CharT, _Traits>::__read_mode() {
1101  if (!(__cm_ & ios_base::in)) {
1102    this->setp(nullptr, nullptr);
1103    if (__always_noconv_)
1104      this->setg((char_type*)__extbuf_, (char_type*)__extbuf_ + __ebs_, (char_type*)__extbuf_ + __ebs_);
1105    else
1106      this->setg(__intbuf_, __intbuf_ + __ibs_, __intbuf_ + __ibs_);
1107    __cm_ = ios_base::in;
1108    return true;
1109  }
1110  return false;
1111}
1112
1113template <class _CharT, class _Traits>
1114void basic_filebuf<_CharT, _Traits>::__write_mode() {
1115  if (!(__cm_ & ios_base::out)) {
1116    this->setg(nullptr, nullptr, nullptr);
1117    if (__ebs_ > sizeof(__extbuf_min_)) {
1118      if (__always_noconv_)
1119        this->setp((char_type*)__extbuf_, (char_type*)__extbuf_ + (__ebs_ - 1));
1120      else
1121        this->setp(__intbuf_, __intbuf_ + (__ibs_ - 1));
1122    } else
1123      this->setp(nullptr, nullptr);
1124    __cm_ = ios_base::out;
1125  }
1126}
1127
1128// basic_ifstream
1129
1130template <class _CharT, class _Traits>
1131class basic_ifstream : public basic_istream<_CharT, _Traits> {
1132public:
1133  typedef _CharT char_type;
1134  typedef _Traits traits_type;
1135  typedef typename traits_type::int_type int_type;
1136  typedef typename traits_type::pos_type pos_type;
1137  typedef typename traits_type::off_type off_type;
1138#    if _LIBCPP_STD_VER >= 26
1139  using native_handle_type = typename basic_filebuf<_CharT, _Traits>::native_handle_type;
1140#    endif
1141
1142  _LIBCPP_HIDE_FROM_ABI basic_ifstream();
1143  _LIBCPP_HIDE_FROM_ABI explicit basic_ifstream(const char* __s, ios_base::openmode __mode = ios_base::in);
1144#    if _LIBCPP_HAS_OPEN_WITH_WCHAR
1145  _LIBCPP_HIDE_FROM_ABI explicit basic_ifstream(const wchar_t* __s, ios_base::openmode __mode = ios_base::in);
1146#    endif
1147  _LIBCPP_HIDE_FROM_ABI explicit basic_ifstream(const string& __s, ios_base::openmode __mode = ios_base::in);
1148#    if _LIBCPP_STD_VER >= 17
1149  template <class _Tp, class = enable_if_t<is_same_v<_Tp, filesystem::path>>>
1150  _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY
1151      _LIBCPP_HIDE_FROM_ABI explicit basic_ifstream(const _Tp& __p, ios_base::openmode __mode = ios_base::in)
1152      : basic_ifstream(__p.c_str(), __mode) {}
1153#    endif // _LIBCPP_STD_VER >= 17
1154  _LIBCPP_HIDE_FROM_ABI basic_ifstream(basic_ifstream&& __rhs);
1155  _LIBCPP_HIDE_FROM_ABI basic_ifstream& operator=(basic_ifstream&& __rhs);
1156  _LIBCPP_HIDE_FROM_ABI void swap(basic_ifstream& __rhs);
1157
1158  _LIBCPP_HIDE_FROM_ABI basic_filebuf<char_type, traits_type>* rdbuf() const;
1159#    if _LIBCPP_STD_VER >= 26
1160  _LIBCPP_HIDE_FROM_ABI native_handle_type native_handle() const noexcept { return rdbuf()->native_handle(); }
1161#    endif
1162  _LIBCPP_HIDE_FROM_ABI bool is_open() const;
1163  void open(const char* __s, ios_base::openmode __mode = ios_base::in);
1164#    if _LIBCPP_HAS_OPEN_WITH_WCHAR
1165  void open(const wchar_t* __s, ios_base::openmode __mode = ios_base::in);
1166#    endif
1167  void open(const string& __s, ios_base::openmode __mode = ios_base::in);
1168#    if _LIBCPP_STD_VER >= 17
1169  _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY _LIBCPP_HIDE_FROM_ABI void
1170  open(const filesystem::path& __p, ios_base::openmode __mode = ios_base::in) {
1171    return open(__p.c_str(), __mode);
1172  }
1173#    endif // _LIBCPP_STD_VER >= 17
1174
1175  _LIBCPP_HIDE_FROM_ABI void __open(int __fd, ios_base::openmode __mode);
1176  _LIBCPP_HIDE_FROM_ABI void close();
1177
1178private:
1179  basic_filebuf<char_type, traits_type> __sb_;
1180};
1181
1182template <class _CharT, class _Traits>
1183inline basic_ifstream<_CharT, _Traits>::basic_ifstream()
1184    : basic_istream<char_type, traits_type>(std::addressof(__sb_)) {}
1185
1186template <class _CharT, class _Traits>
1187inline basic_ifstream<_CharT, _Traits>::basic_ifstream(const char* __s, ios_base::openmode __mode)
1188    : basic_istream<char_type, traits_type>(std::addressof(__sb_)) {
1189  if (__sb_.open(__s, __mode | ios_base::in) == nullptr)
1190    this->setstate(ios_base::failbit);
1191}
1192
1193#    if _LIBCPP_HAS_OPEN_WITH_WCHAR
1194template <class _CharT, class _Traits>
1195inline basic_ifstream<_CharT, _Traits>::basic_ifstream(const wchar_t* __s, ios_base::openmode __mode)
1196    : basic_istream<char_type, traits_type>(std::addressof(__sb_)) {
1197  if (__sb_.open(__s, __mode | ios_base::in) == nullptr)
1198    this->setstate(ios_base::failbit);
1199}
1200#    endif
1201
1202// extension
1203template <class _CharT, class _Traits>
1204inline basic_ifstream<_CharT, _Traits>::basic_ifstream(const string& __s, ios_base::openmode __mode)
1205    : basic_istream<char_type, traits_type>(std::addressof(__sb_)) {
1206  if (__sb_.open(__s, __mode | ios_base::in) == nullptr)
1207    this->setstate(ios_base::failbit);
1208}
1209
1210template <class _CharT, class _Traits>
1211inline basic_ifstream<_CharT, _Traits>::basic_ifstream(basic_ifstream&& __rhs)
1212    : basic_istream<char_type, traits_type>(std::move(__rhs)), __sb_(std::move(__rhs.__sb_)) {
1213  this->set_rdbuf(std::addressof(__sb_));
1214}
1215
1216template <class _CharT, class _Traits>
1217inline basic_ifstream<_CharT, _Traits>& basic_ifstream<_CharT, _Traits>::operator=(basic_ifstream&& __rhs) {
1218  basic_istream<char_type, traits_type>::operator=(std::move(__rhs));
1219  __sb_ = std::move(__rhs.__sb_);
1220  return *this;
1221}
1222
1223template <class _CharT, class _Traits>
1224inline void basic_ifstream<_CharT, _Traits>::swap(basic_ifstream& __rhs) {
1225  basic_istream<char_type, traits_type>::swap(__rhs);
1226  __sb_.swap(__rhs.__sb_);
1227}
1228
1229template <class _CharT, class _Traits>
1230inline _LIBCPP_HIDE_FROM_ABI void swap(basic_ifstream<_CharT, _Traits>& __x, basic_ifstream<_CharT, _Traits>& __y) {
1231  __x.swap(__y);
1232}
1233
1234template <class _CharT, class _Traits>
1235inline basic_filebuf<_CharT, _Traits>* basic_ifstream<_CharT, _Traits>::rdbuf() const {
1236  return const_cast<basic_filebuf<char_type, traits_type>*>(std::addressof(__sb_));
1237}
1238
1239template <class _CharT, class _Traits>
1240inline bool basic_ifstream<_CharT, _Traits>::is_open() const {
1241  return __sb_.is_open();
1242}
1243
1244template <class _CharT, class _Traits>
1245void basic_ifstream<_CharT, _Traits>::open(const char* __s, ios_base::openmode __mode) {
1246  if (__sb_.open(__s, __mode | ios_base::in))
1247    this->clear();
1248  else
1249    this->setstate(ios_base::failbit);
1250}
1251
1252#    if _LIBCPP_HAS_OPEN_WITH_WCHAR
1253template <class _CharT, class _Traits>
1254void basic_ifstream<_CharT, _Traits>::open(const wchar_t* __s, ios_base::openmode __mode) {
1255  if (__sb_.open(__s, __mode | ios_base::in))
1256    this->clear();
1257  else
1258    this->setstate(ios_base::failbit);
1259}
1260#    endif
1261
1262template <class _CharT, class _Traits>
1263void basic_ifstream<_CharT, _Traits>::open(const string& __s, ios_base::openmode __mode) {
1264  if (__sb_.open(__s, __mode | ios_base::in))
1265    this->clear();
1266  else
1267    this->setstate(ios_base::failbit);
1268}
1269
1270template <class _CharT, class _Traits>
1271inline void basic_ifstream<_CharT, _Traits>::__open(int __fd, ios_base::openmode __mode) {
1272  if (__sb_.__open(__fd, __mode | ios_base::in))
1273    this->clear();
1274  else
1275    this->setstate(ios_base::failbit);
1276}
1277
1278template <class _CharT, class _Traits>
1279inline void basic_ifstream<_CharT, _Traits>::close() {
1280  if (__sb_.close() == 0)
1281    this->setstate(ios_base::failbit);
1282}
1283
1284// basic_ofstream
1285
1286template <class _CharT, class _Traits>
1287class basic_ofstream : public basic_ostream<_CharT, _Traits> {
1288public:
1289  typedef _CharT char_type;
1290  typedef _Traits traits_type;
1291  typedef typename traits_type::int_type int_type;
1292  typedef typename traits_type::pos_type pos_type;
1293  typedef typename traits_type::off_type off_type;
1294#    if _LIBCPP_STD_VER >= 26
1295  using native_handle_type = typename basic_filebuf<_CharT, _Traits>::native_handle_type;
1296#    endif
1297
1298  _LIBCPP_HIDE_FROM_ABI basic_ofstream();
1299  _LIBCPP_HIDE_FROM_ABI explicit basic_ofstream(const char* __s, ios_base::openmode __mode = ios_base::out);
1300#    if _LIBCPP_HAS_OPEN_WITH_WCHAR
1301  _LIBCPP_HIDE_FROM_ABI explicit basic_ofstream(const wchar_t* __s, ios_base::openmode __mode = ios_base::out);
1302#    endif
1303  _LIBCPP_HIDE_FROM_ABI explicit basic_ofstream(const string& __s, ios_base::openmode __mode = ios_base::out);
1304
1305#    if _LIBCPP_STD_VER >= 17
1306  template <class _Tp, class = enable_if_t<is_same_v<_Tp, filesystem::path>>>
1307  _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY
1308      _LIBCPP_HIDE_FROM_ABI explicit basic_ofstream(const _Tp& __p, ios_base::openmode __mode = ios_base::out)
1309      : basic_ofstream(__p.c_str(), __mode) {}
1310#    endif // _LIBCPP_STD_VER >= 17
1311
1312  _LIBCPP_HIDE_FROM_ABI basic_ofstream(basic_ofstream&& __rhs);
1313  _LIBCPP_HIDE_FROM_ABI basic_ofstream& operator=(basic_ofstream&& __rhs);
1314  _LIBCPP_HIDE_FROM_ABI void swap(basic_ofstream& __rhs);
1315
1316  _LIBCPP_HIDE_FROM_ABI basic_filebuf<char_type, traits_type>* rdbuf() const;
1317#    if _LIBCPP_STD_VER >= 26
1318  _LIBCPP_HIDE_FROM_ABI native_handle_type native_handle() const noexcept { return rdbuf()->native_handle(); }
1319#    endif
1320  _LIBCPP_HIDE_FROM_ABI bool is_open() const;
1321  void open(const char* __s, ios_base::openmode __mode = ios_base::out);
1322#    if _LIBCPP_HAS_OPEN_WITH_WCHAR
1323  void open(const wchar_t* __s, ios_base::openmode __mode = ios_base::out);
1324#    endif
1325  void open(const string& __s, ios_base::openmode __mode = ios_base::out);
1326
1327#    if _LIBCPP_STD_VER >= 17
1328  _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY _LIBCPP_HIDE_FROM_ABI void
1329  open(const filesystem::path& __p, ios_base::openmode __mode = ios_base::out) {
1330    return open(__p.c_str(), __mode);
1331  }
1332#    endif // _LIBCPP_STD_VER >= 17
1333
1334  _LIBCPP_HIDE_FROM_ABI void __open(int __fd, ios_base::openmode __mode);
1335  _LIBCPP_HIDE_FROM_ABI void close();
1336
1337private:
1338  basic_filebuf<char_type, traits_type> __sb_;
1339};
1340
1341template <class _CharT, class _Traits>
1342inline basic_ofstream<_CharT, _Traits>::basic_ofstream()
1343    : basic_ostream<char_type, traits_type>(std::addressof(__sb_)) {}
1344
1345template <class _CharT, class _Traits>
1346inline basic_ofstream<_CharT, _Traits>::basic_ofstream(const char* __s, ios_base::openmode __mode)
1347    : basic_ostream<char_type, traits_type>(std::addressof(__sb_)) {
1348  if (__sb_.open(__s, __mode | ios_base::out) == nullptr)
1349    this->setstate(ios_base::failbit);
1350}
1351
1352#    if _LIBCPP_HAS_OPEN_WITH_WCHAR
1353template <class _CharT, class _Traits>
1354inline basic_ofstream<_CharT, _Traits>::basic_ofstream(const wchar_t* __s, ios_base::openmode __mode)
1355    : basic_ostream<char_type, traits_type>(std::addressof(__sb_)) {
1356  if (__sb_.open(__s, __mode | ios_base::out) == nullptr)
1357    this->setstate(ios_base::failbit);
1358}
1359#    endif
1360
1361// extension
1362template <class _CharT, class _Traits>
1363inline basic_ofstream<_CharT, _Traits>::basic_ofstream(const string& __s, ios_base::openmode __mode)
1364    : basic_ostream<char_type, traits_type>(std::addressof(__sb_)) {
1365  if (__sb_.open(__s, __mode | ios_base::out) == nullptr)
1366    this->setstate(ios_base::failbit);
1367}
1368
1369template <class _CharT, class _Traits>
1370inline basic_ofstream<_CharT, _Traits>::basic_ofstream(basic_ofstream&& __rhs)
1371    : basic_ostream<char_type, traits_type>(std::move(__rhs)), __sb_(std::move(__rhs.__sb_)) {
1372  this->set_rdbuf(std::addressof(__sb_));
1373}
1374
1375template <class _CharT, class _Traits>
1376inline basic_ofstream<_CharT, _Traits>& basic_ofstream<_CharT, _Traits>::operator=(basic_ofstream&& __rhs) {
1377  basic_ostream<char_type, traits_type>::operator=(std::move(__rhs));
1378  __sb_ = std::move(__rhs.__sb_);
1379  return *this;
1380}
1381
1382template <class _CharT, class _Traits>
1383inline void basic_ofstream<_CharT, _Traits>::swap(basic_ofstream& __rhs) {
1384  basic_ostream<char_type, traits_type>::swap(__rhs);
1385  __sb_.swap(__rhs.__sb_);
1386}
1387
1388template <class _CharT, class _Traits>
1389inline _LIBCPP_HIDE_FROM_ABI void swap(basic_ofstream<_CharT, _Traits>& __x, basic_ofstream<_CharT, _Traits>& __y) {
1390  __x.swap(__y);
1391}
1392
1393template <class _CharT, class _Traits>
1394inline basic_filebuf<_CharT, _Traits>* basic_ofstream<_CharT, _Traits>::rdbuf() const {
1395  return const_cast<basic_filebuf<char_type, traits_type>*>(std::addressof(__sb_));
1396}
1397
1398template <class _CharT, class _Traits>
1399inline bool basic_ofstream<_CharT, _Traits>::is_open() const {
1400  return __sb_.is_open();
1401}
1402
1403template <class _CharT, class _Traits>
1404void basic_ofstream<_CharT, _Traits>::open(const char* __s, ios_base::openmode __mode) {
1405  if (__sb_.open(__s, __mode | ios_base::out))
1406    this->clear();
1407  else
1408    this->setstate(ios_base::failbit);
1409}
1410
1411#    if _LIBCPP_HAS_OPEN_WITH_WCHAR
1412template <class _CharT, class _Traits>
1413void basic_ofstream<_CharT, _Traits>::open(const wchar_t* __s, ios_base::openmode __mode) {
1414  if (__sb_.open(__s, __mode | ios_base::out))
1415    this->clear();
1416  else
1417    this->setstate(ios_base::failbit);
1418}
1419#    endif
1420
1421template <class _CharT, class _Traits>
1422void basic_ofstream<_CharT, _Traits>::open(const string& __s, ios_base::openmode __mode) {
1423  if (__sb_.open(__s, __mode | ios_base::out))
1424    this->clear();
1425  else
1426    this->setstate(ios_base::failbit);
1427}
1428
1429template <class _CharT, class _Traits>
1430inline void basic_ofstream<_CharT, _Traits>::__open(int __fd, ios_base::openmode __mode) {
1431  if (__sb_.__open(__fd, __mode | ios_base::out))
1432    this->clear();
1433  else
1434    this->setstate(ios_base::failbit);
1435}
1436
1437template <class _CharT, class _Traits>
1438inline void basic_ofstream<_CharT, _Traits>::close() {
1439  if (__sb_.close() == nullptr)
1440    this->setstate(ios_base::failbit);
1441}
1442
1443// basic_fstream
1444
1445template <class _CharT, class _Traits>
1446class basic_fstream : public basic_iostream<_CharT, _Traits> {
1447public:
1448  typedef _CharT char_type;
1449  typedef _Traits traits_type;
1450  typedef typename traits_type::int_type int_type;
1451  typedef typename traits_type::pos_type pos_type;
1452  typedef typename traits_type::off_type off_type;
1453#    if _LIBCPP_STD_VER >= 26
1454  using native_handle_type = typename basic_filebuf<_CharT, _Traits>::native_handle_type;
1455#    endif
1456
1457  _LIBCPP_HIDE_FROM_ABI basic_fstream();
1458  _LIBCPP_HIDE_FROM_ABI explicit basic_fstream(const char* __s,
1459                                               ios_base::openmode __mode = ios_base::in | ios_base::out);
1460#    if _LIBCPP_HAS_OPEN_WITH_WCHAR
1461  _LIBCPP_HIDE_FROM_ABI explicit basic_fstream(const wchar_t* __s,
1462                                               ios_base::openmode __mode = ios_base::in | ios_base::out);
1463#    endif
1464  _LIBCPP_HIDE_FROM_ABI explicit basic_fstream(const string& __s,
1465                                               ios_base::openmode __mode = ios_base::in | ios_base::out);
1466
1467#    if _LIBCPP_STD_VER >= 17
1468  template <class _Tp, class = enable_if_t<is_same_v<_Tp, filesystem::path>>>
1469  _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY _LIBCPP_HIDE_FROM_ABI explicit basic_fstream(
1470      const _Tp& __p, ios_base::openmode __mode = ios_base::in | ios_base::out)
1471      : basic_fstream(__p.c_str(), __mode) {}
1472#    endif // _LIBCPP_STD_VER >= 17
1473
1474  _LIBCPP_HIDE_FROM_ABI basic_fstream(basic_fstream&& __rhs);
1475
1476  _LIBCPP_HIDE_FROM_ABI basic_fstream& operator=(basic_fstream&& __rhs);
1477
1478  _LIBCPP_HIDE_FROM_ABI void swap(basic_fstream& __rhs);
1479
1480  _LIBCPP_HIDE_FROM_ABI basic_filebuf<char_type, traits_type>* rdbuf() const;
1481#    if _LIBCPP_STD_VER >= 26
1482  _LIBCPP_HIDE_FROM_ABI native_handle_type native_handle() const noexcept { return rdbuf()->native_handle(); }
1483#    endif
1484  _LIBCPP_HIDE_FROM_ABI bool is_open() const;
1485  _LIBCPP_HIDE_FROM_ABI void open(const char* __s, ios_base::openmode __mode = ios_base::in | ios_base::out);
1486#    if _LIBCPP_HAS_OPEN_WITH_WCHAR
1487  void open(const wchar_t* __s, ios_base::openmode __mode = ios_base::in | ios_base::out);
1488#    endif
1489  _LIBCPP_HIDE_FROM_ABI void open(const string& __s, ios_base::openmode __mode = ios_base::in | ios_base::out);
1490
1491#    if _LIBCPP_STD_VER >= 17
1492  _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY _LIBCPP_HIDE_FROM_ABI void
1493  open(const filesystem::path& __p, ios_base::openmode __mode = ios_base::in | ios_base::out) {
1494    return open(__p.c_str(), __mode);
1495  }
1496#    endif // _LIBCPP_STD_VER >= 17
1497
1498  _LIBCPP_HIDE_FROM_ABI void close();
1499
1500private:
1501  basic_filebuf<char_type, traits_type> __sb_;
1502};
1503
1504template <class _CharT, class _Traits>
1505inline basic_fstream<_CharT, _Traits>::basic_fstream()
1506    : basic_iostream<char_type, traits_type>(std::addressof(__sb_)) {}
1507
1508template <class _CharT, class _Traits>
1509inline basic_fstream<_CharT, _Traits>::basic_fstream(const char* __s, ios_base::openmode __mode)
1510    : basic_iostream<char_type, traits_type>(std::addressof(__sb_)) {
1511  if (__sb_.open(__s, __mode) == nullptr)
1512    this->setstate(ios_base::failbit);
1513}
1514
1515#    if _LIBCPP_HAS_OPEN_WITH_WCHAR
1516template <class _CharT, class _Traits>
1517inline basic_fstream<_CharT, _Traits>::basic_fstream(const wchar_t* __s, ios_base::openmode __mode)
1518    : basic_iostream<char_type, traits_type>(std::addressof(__sb_)) {
1519  if (__sb_.open(__s, __mode) == nullptr)
1520    this->setstate(ios_base::failbit);
1521}
1522#    endif
1523
1524template <class _CharT, class _Traits>
1525inline basic_fstream<_CharT, _Traits>::basic_fstream(const string& __s, ios_base::openmode __mode)
1526    : basic_iostream<char_type, traits_type>(std::addressof(__sb_)) {
1527  if (__sb_.open(__s, __mode) == nullptr)
1528    this->setstate(ios_base::failbit);
1529}
1530
1531// extension
1532template <class _CharT, class _Traits>
1533inline basic_fstream<_CharT, _Traits>::basic_fstream(basic_fstream&& __rhs)
1534    : basic_iostream<char_type, traits_type>(std::move(__rhs)), __sb_(std::move(__rhs.__sb_)) {
1535  this->set_rdbuf(std::addressof(__sb_));
1536}
1537
1538template <class _CharT, class _Traits>
1539inline basic_fstream<_CharT, _Traits>& basic_fstream<_CharT, _Traits>::operator=(basic_fstream&& __rhs) {
1540  basic_iostream<char_type, traits_type>::operator=(std::move(__rhs));
1541  __sb_ = std::move(__rhs.__sb_);
1542  return *this;
1543}
1544
1545template <class _CharT, class _Traits>
1546inline void basic_fstream<_CharT, _Traits>::swap(basic_fstream& __rhs) {
1547  basic_iostream<char_type, traits_type>::swap(__rhs);
1548  __sb_.swap(__rhs.__sb_);
1549}
1550
1551template <class _CharT, class _Traits>
1552inline _LIBCPP_HIDE_FROM_ABI void swap(basic_fstream<_CharT, _Traits>& __x, basic_fstream<_CharT, _Traits>& __y) {
1553  __x.swap(__y);
1554}
1555
1556template <class _CharT, class _Traits>
1557inline basic_filebuf<_CharT, _Traits>* basic_fstream<_CharT, _Traits>::rdbuf() const {
1558  return const_cast<basic_filebuf<char_type, traits_type>*>(std::addressof(__sb_));
1559}
1560
1561template <class _CharT, class _Traits>
1562inline bool basic_fstream<_CharT, _Traits>::is_open() const {
1563  return __sb_.is_open();
1564}
1565
1566template <class _CharT, class _Traits>
1567void basic_fstream<_CharT, _Traits>::open(const char* __s, ios_base::openmode __mode) {
1568  if (__sb_.open(__s, __mode))
1569    this->clear();
1570  else
1571    this->setstate(ios_base::failbit);
1572}
1573
1574#    if _LIBCPP_HAS_OPEN_WITH_WCHAR
1575template <class _CharT, class _Traits>
1576void basic_fstream<_CharT, _Traits>::open(const wchar_t* __s, ios_base::openmode __mode) {
1577  if (__sb_.open(__s, __mode))
1578    this->clear();
1579  else
1580    this->setstate(ios_base::failbit);
1581}
1582#    endif
1583
1584template <class _CharT, class _Traits>
1585void basic_fstream<_CharT, _Traits>::open(const string& __s, ios_base::openmode __mode) {
1586  if (__sb_.open(__s, __mode))
1587    this->clear();
1588  else
1589    this->setstate(ios_base::failbit);
1590}
1591
1592template <class _CharT, class _Traits>
1593inline void basic_fstream<_CharT, _Traits>::close() {
1594  if (__sb_.close() == nullptr)
1595    this->setstate(ios_base::failbit);
1596}
1597
1598#    if _LIBCPP_AVAILABILITY_HAS_ADDITIONAL_IOSTREAM_EXPLICIT_INSTANTIATIONS_1
1599extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_ifstream<char>;
1600extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_ofstream<char>;
1601extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_filebuf<char>;
1602#    endif
1603
1604_LIBCPP_END_NAMESPACE_STD
1605
1606_LIBCPP_POP_MACROS
1607
1608#  endif // _LIBCPP_HAS_FILESYSTEM && _LIBCPP_HAS_LOCALIZATION
1609
1610#  if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
1611#    include <atomic>
1612#    include <concepts>
1613#    include <cstdlib>
1614#    include <iosfwd>
1615#    include <limits>
1616#    include <mutex>
1617#    include <new>
1618#    include <stdexcept>
1619#    include <type_traits>
1620#  endif
1621
1622#  if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 23
1623#    include <filesystem>
1624#  endif
1625#endif // __cplusplus < 201103L && defined(_LIBCPP_USE_FROZEN_CXX03_HEADERS)
1626
1627#endif // _LIBCPP_FSTREAM
1628