libstdc++
iomanip
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1 // Standard stream manipulators -*- C++ -*-
2 
3 // Copyright (C) 1997-2024 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
9 // any later version.
10 
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
15 
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
19 
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
24 
25 /** @file include/iomanip
26  * This is a Standard C++ Library header.
27  */
28 
29 //
30 // ISO C++ 14882: 27.6.3 Standard manipulators
31 //
32 
33 #ifndef _GLIBCXX_IOMANIP
34 #define _GLIBCXX_IOMANIP 1
35 
36 #pragma GCC system_header
37 
38 #include <bits/requires_hosted.h> // iostreams
39 
40 #include <bits/c++config.h>
41 #include <iosfwd>
42 #include <bits/ios_base.h>
43 
44 #define __glibcxx_want_quoted_string_io
45 #include <bits/version.h>
46 
47 #if __cplusplus >= 201103L
48 #include <locale>
49 #if __cplusplus > 201103L
50 #include <bits/quoted_string.h>
51 #endif
52 #endif
53 
54 namespace std _GLIBCXX_VISIBILITY(default)
55 {
56 _GLIBCXX_BEGIN_NAMESPACE_VERSION
57 
58  // [27.6.3] standard manipulators
59  // Also see DR 183.
60 
61  struct _Resetiosflags { ios_base::fmtflags _M_mask; };
62 
63  /**
64  * @brief Manipulator for @c setf.
65  * @param __mask A format flags mask.
66  *
67  * Sent to a stream object, this manipulator resets the specified flags,
68  * via @e stream.setf(0,__mask).
69  */
70  inline _Resetiosflags
71  resetiosflags(ios_base::fmtflags __mask)
72  { return { __mask }; }
73 
74  template<typename _CharT, typename _Traits>
75  inline basic_istream<_CharT, _Traits>&
76  operator>>(basic_istream<_CharT, _Traits>& __is, _Resetiosflags __f)
77  {
78  __is.setf(ios_base::fmtflags(0), __f._M_mask);
79  return __is;
80  }
81 
82  template<typename _CharT, typename _Traits>
83  inline basic_ostream<_CharT, _Traits>&
84  operator<<(basic_ostream<_CharT, _Traits>& __os, _Resetiosflags __f)
85  {
86  __os.setf(ios_base::fmtflags(0), __f._M_mask);
87  return __os;
88  }
89 
90 
91  struct _Setiosflags { ios_base::fmtflags _M_mask; };
92 
93  /**
94  * @brief Manipulator for @c setf.
95  * @param __mask A format flags mask.
96  *
97  * Sent to a stream object, this manipulator sets the format flags
98  * to @a __mask.
99  */
100  inline _Setiosflags
101  setiosflags(ios_base::fmtflags __mask)
102  { return { __mask }; }
103 
104  template<typename _CharT, typename _Traits>
105  inline basic_istream<_CharT, _Traits>&
106  operator>>(basic_istream<_CharT, _Traits>& __is, _Setiosflags __f)
107  {
108  __is.setf(__f._M_mask);
109  return __is;
110  }
111 
112  template<typename _CharT, typename _Traits>
113  inline basic_ostream<_CharT, _Traits>&
114  operator<<(basic_ostream<_CharT, _Traits>& __os, _Setiosflags __f)
115  {
116  __os.setf(__f._M_mask);
117  return __os;
118  }
119 
120 
121  struct _Setbase { int _M_base; };
122 
123  /**
124  * @brief Manipulator for @c setf.
125  * @param __base A numeric base.
126  *
127  * Sent to a stream object, this manipulator changes the
128  * @c ios_base::basefield flags to @c oct, @c dec, or @c hex when @a base
129  * is 8, 10, or 16, accordingly, and to 0 if @a __base is any other value.
130  */
131  inline _Setbase
132  setbase(int __base)
133  { return { __base }; }
134 
135  template<typename _CharT, typename _Traits>
136  inline basic_istream<_CharT, _Traits>&
137  operator>>(basic_istream<_CharT, _Traits>& __is, _Setbase __f)
138  {
139  __is.setf(__f._M_base == 8 ? ios_base::oct :
140  __f._M_base == 10 ? ios_base::dec :
141  __f._M_base == 16 ? ios_base::hex :
142  ios_base::fmtflags(0), ios_base::basefield);
143  return __is;
144  }
145 
146  template<typename _CharT, typename _Traits>
147  inline basic_ostream<_CharT, _Traits>&
148  operator<<(basic_ostream<_CharT, _Traits>& __os, _Setbase __f)
149  {
150  __os.setf(__f._M_base == 8 ? ios_base::oct :
151  __f._M_base == 10 ? ios_base::dec :
152  __f._M_base == 16 ? ios_base::hex :
153  ios_base::fmtflags(0), ios_base::basefield);
154  return __os;
155  }
156 
157 
158  template<typename _CharT>
159  struct _Setfill { _CharT _M_c; };
160 
161  /**
162  * @brief Manipulator for @c fill.
163  * @param __c The new fill character.
164  *
165  * Sent to a stream object, this manipulator calls @c fill(__c) for that
166  * object.
167  */
168  template<typename _CharT>
169  inline _Setfill<_CharT>
170  setfill(_CharT __c)
171  { return { __c }; }
172 
173  template<typename _CharT, typename _Traits>
174  __attribute__((__deprecated__("'std::setfill' should only be used with "
175  "output streams")))
176  inline basic_istream<_CharT, _Traits>&
177  operator>>(basic_istream<_CharT, _Traits>& __is, _Setfill<_CharT> __f)
178  {
179  __is.fill(__f._M_c);
180  return __is;
181  }
182 
183  template<typename _CharT, typename _Traits>
184  inline basic_ostream<_CharT, _Traits>&
185  operator<<(basic_ostream<_CharT, _Traits>& __os, _Setfill<_CharT> __f)
186  {
187  __os.fill(__f._M_c);
188  return __os;
189  }
190 
191 
192  struct _Setprecision { int _M_n; };
193 
194  /**
195  * @brief Manipulator for @c precision.
196  * @param __n The new precision.
197  *
198  * Sent to a stream object, this manipulator calls @c precision(__n) for
199  * that object.
200  */
201  inline _Setprecision
202  setprecision(int __n)
203  { return { __n }; }
204 
205  template<typename _CharT, typename _Traits>
206  inline basic_istream<_CharT, _Traits>&
207  operator>>(basic_istream<_CharT, _Traits>& __is, _Setprecision __f)
208  {
209  __is.precision(__f._M_n);
210  return __is;
211  }
212 
213  template<typename _CharT, typename _Traits>
214  inline basic_ostream<_CharT, _Traits>&
215  operator<<(basic_ostream<_CharT, _Traits>& __os, _Setprecision __f)
216  {
217  __os.precision(__f._M_n);
218  return __os;
219  }
220 
221 
222  struct _Setw { int _M_n; };
223 
224  /**
225  * @brief Manipulator for @c width.
226  * @param __n The new width.
227  *
228  * Sent to a stream object, this manipulator calls @c width(__n) for
229  * that object.
230  */
231  inline _Setw
232  setw(int __n)
233  { return { __n }; }
234 
235  template<typename _CharT, typename _Traits>
236  inline basic_istream<_CharT, _Traits>&
237  operator>>(basic_istream<_CharT, _Traits>& __is, _Setw __f)
238  {
239  __is.width(__f._M_n);
240  return __is;
241  }
242 
243  template<typename _CharT, typename _Traits>
244  inline basic_ostream<_CharT, _Traits>&
245  operator<<(basic_ostream<_CharT, _Traits>& __os, _Setw __f)
246  {
247  __os.width(__f._M_n);
248  return __os;
249  }
250 
251 #if __cplusplus >= 201103L
252 
253  template<typename _MoneyT>
254  struct _Get_money { _MoneyT& _M_mon; bool _M_intl; };
255 
256  /**
257  * @brief Extended manipulator for extracting money.
258  * @param __mon Either long double or a specialization of @c basic_string.
259  * @param __intl A bool indicating whether international format
260  * is to be used.
261  *
262  * Sent to a stream object, this manipulator extracts @a __mon.
263  */
264  template<typename _MoneyT>
265  inline _Get_money<_MoneyT>
266  get_money(_MoneyT& __mon, bool __intl = false)
267  { return { __mon, __intl }; }
268 
269  template<typename _CharT, typename _Traits, typename _MoneyT>
270  basic_istream<_CharT, _Traits>&
271  operator>>(basic_istream<_CharT, _Traits>& __is, _Get_money<_MoneyT> __f)
272  {
273  typename basic_istream<_CharT, _Traits>::sentry __cerb(__is, false);
274  if (__cerb)
275  {
276  ios_base::iostate __err = ios_base::goodbit;
277  __try
278  {
279  typedef istreambuf_iterator<_CharT, _Traits> _Iter;
280  typedef money_get<_CharT, _Iter> _MoneyGet;
281 
282  const _MoneyGet& __mg = use_facet<_MoneyGet>(__is.getloc());
283  __mg.get(_Iter(__is.rdbuf()), _Iter(), __f._M_intl,
284  __is, __err, __f._M_mon);
285  }
286  __catch(__cxxabiv1::__forced_unwind&)
287  {
288  __is._M_setstate(ios_base::badbit);
289  __throw_exception_again;
290  }
291  __catch(...)
292  { __is._M_setstate(ios_base::badbit); }
293  if (__err)
294  __is.setstate(__err);
295  }
296  return __is;
297  }
298 
299 
300  template<typename _MoneyT>
301  struct _Put_money { const _MoneyT& _M_mon; bool _M_intl; };
302 
303  /**
304  * @brief Extended manipulator for inserting money.
305  * @param __mon Either long double or a specialization of @c basic_string.
306  * @param __intl A bool indicating whether international format
307  * is to be used.
308  *
309  * Sent to a stream object, this manipulator inserts @a __mon.
310  */
311  template<typename _MoneyT>
312  inline _Put_money<_MoneyT>
313  put_money(const _MoneyT& __mon, bool __intl = false)
314  { return { __mon, __intl }; }
315 
316  template<typename _CharT, typename _Traits, typename _MoneyT>
317  basic_ostream<_CharT, _Traits>&
318  operator<<(basic_ostream<_CharT, _Traits>& __os, _Put_money<_MoneyT> __f)
319  {
320  typename basic_ostream<_CharT, _Traits>::sentry __cerb(__os);
321  if (__cerb)
322  {
323  ios_base::iostate __err = ios_base::goodbit;
324  __try
325  {
326  typedef ostreambuf_iterator<_CharT, _Traits> _Iter;
327  typedef money_put<_CharT, _Iter> _MoneyPut;
328 
329  const _MoneyPut& __mp = use_facet<_MoneyPut>(__os.getloc());
330  if (__mp.put(_Iter(__os.rdbuf()), __f._M_intl, __os,
331  __os.fill(), __f._M_mon).failed())
332  __err |= ios_base::badbit;
333  }
334  __catch(__cxxabiv1::__forced_unwind&)
335  {
336  __os._M_setstate(ios_base::badbit);
337  __throw_exception_again;
338  }
339  __catch(...)
340  { __os._M_setstate(ios_base::badbit); }
341  if (__err)
342  __os.setstate(__err);
343  }
344  return __os;
345  }
346 
347  template<typename _CharT>
348  struct _Put_time
349  {
350  const std::tm* _M_tmb;
351  const _CharT* _M_fmt;
352  };
353 
354  /**
355  * @brief Extended manipulator for formatting time.
356  *
357  * This manipulator uses time_put::put to format time.
358  * [ext.manip]
359  *
360  * @param __tmb struct tm time data to format.
361  * @param __fmt format string.
362  */
363  template<typename _CharT>
364  inline _Put_time<_CharT>
365  put_time(const std::tm* __tmb, const _CharT* __fmt)
366  { return { __tmb, __fmt }; }
367 
368  template<typename _CharT, typename _Traits>
369  basic_ostream<_CharT, _Traits>&
370  operator<<(basic_ostream<_CharT, _Traits>& __os, _Put_time<_CharT> __f)
371  {
372  typename basic_ostream<_CharT, _Traits>::sentry __cerb(__os);
373  if (__cerb)
374  {
375  ios_base::iostate __err = ios_base::goodbit;
376  __try
377  {
378  typedef ostreambuf_iterator<_CharT, _Traits> _Iter;
379  typedef time_put<_CharT, _Iter> _TimePut;
380 
381  const _CharT* const __fmt_end = __f._M_fmt +
382  _Traits::length(__f._M_fmt);
383 
384  const _TimePut& __mp = use_facet<_TimePut>(__os.getloc());
385  if (__mp.put(_Iter(__os.rdbuf()), __os, __os.fill(),
386  __f._M_tmb, __f._M_fmt, __fmt_end).failed())
387  __err |= ios_base::badbit;
388  }
389  __catch(__cxxabiv1::__forced_unwind&)
390  {
391  __os._M_setstate(ios_base::badbit);
392  __throw_exception_again;
393  }
394  __catch(...)
395  { __os._M_setstate(ios_base::badbit); }
396  if (__err)
397  __os.setstate(__err);
398  }
399  return __os;
400  }
401 
402  template<typename _CharT>
403  struct _Get_time
404  {
405  std::tm* _M_tmb;
406  const _CharT* _M_fmt;
407  };
408 
409  /**
410  * @brief Extended manipulator for extracting time.
411  *
412  * This manipulator uses time_get::get to extract time.
413  * [ext.manip]
414  *
415  * @param __tmb struct to extract the time data to.
416  * @param __fmt format string.
417  */
418  template<typename _CharT>
419  inline _Get_time<_CharT>
420  get_time(std::tm* __tmb, const _CharT* __fmt)
421  { return { __tmb, __fmt }; }
422 
423  template<typename _CharT, typename _Traits>
424  basic_istream<_CharT, _Traits>&
425  operator>>(basic_istream<_CharT, _Traits>& __is, _Get_time<_CharT> __f)
426  {
427  typename basic_istream<_CharT, _Traits>::sentry __cerb(__is, false);
428  if (__cerb)
429  {
430  ios_base::iostate __err = ios_base::goodbit;
431  __try
432  {
433  typedef istreambuf_iterator<_CharT, _Traits> _Iter;
434  typedef time_get<_CharT, _Iter> _TimeGet;
435 
436  const _CharT* const __fmt_end = __f._M_fmt +
437  _Traits::length(__f._M_fmt);
438 
439  const _TimeGet& __mg = use_facet<_TimeGet>(__is.getloc());
440  __mg.get(_Iter(__is.rdbuf()), _Iter(), __is,
441  __err, __f._M_tmb, __f._M_fmt, __fmt_end);
442  }
443  __catch(__cxxabiv1::__forced_unwind&)
444  {
445  __is._M_setstate(ios_base::badbit);
446  __throw_exception_again;
447  }
448  __catch(...)
449  { __is._M_setstate(ios_base::badbit); }
450  if (__err)
451  __is.setstate(__err);
452  }
453  return __is;
454  }
455 
456 #ifdef __cpp_lib_quoted_string_io // C++ >= 14 && HOSTED
457 
458  /**
459  * @brief Manipulator for quoted strings.
460  * @param __string String to quote.
461  * @param __delim Character to quote string with.
462  * @param __escape Escape character to escape itself or quote character.
463  * @since C++14
464  */
465  template<typename _CharT>
466  inline auto
467  quoted(const _CharT* __string,
468  _CharT __delim = _CharT('"'), _CharT __escape = _CharT('\\'))
469  {
470  return __detail::_Quoted_string<const _CharT*, _CharT>(__string, __delim,
471  __escape);
472  }
473 
474  template<typename _CharT, typename _Traits, typename _Alloc>
475  inline auto
476  quoted(const basic_string<_CharT, _Traits, _Alloc>& __string,
477  _CharT __delim = _CharT('"'), _CharT __escape = _CharT('\\'))
478  {
479  return __detail::_Quoted_string<
480  const basic_string<_CharT, _Traits, _Alloc>&, _CharT>(
481  __string, __delim, __escape);
482  }
483 
484  template<typename _CharT, typename _Traits, typename _Alloc>
485  inline auto
486  quoted(basic_string<_CharT, _Traits, _Alloc>& __string,
487  _CharT __delim = _CharT('"'), _CharT __escape = _CharT('\\'))
488  {
489  return __detail::_Quoted_string<
490  basic_string<_CharT, _Traits, _Alloc>&, _CharT>(
491  __string, __delim, __escape);
492  }
493 
494 #if __cplusplus >= 201703L
495  // _GLIBCXX_RESOLVE_LIB_DEFECTS
496  // 2785. quoted should work with basic_string_view
497  template<typename _CharT, typename _Traits>
498  inline auto
499  quoted(basic_string_view<_CharT, _Traits> __sv,
500  _CharT __delim = _CharT('"'), _CharT __escape = _CharT('\\'))
501  {
502  return __detail::_Quoted_string<
503  basic_string_view<_CharT, _Traits>, _CharT>(__sv, __delim, __escape);
504  }
505 #endif // C++17
506 #endif // __cpp_lib_quoted_string_io
507 
508 #endif // __cplusplus >= 201103L
509 
510  // Inhibit implicit instantiations for required instantiations,
511  // which are defined via explicit instantiations elsewhere.
512  // NB: This syntax is a GNU extension.
513 #if _GLIBCXX_EXTERN_TEMPLATE
514  extern template ostream& operator<<(ostream&, _Setfill<char>);
515  extern template ostream& operator<<(ostream&, _Setiosflags);
516  extern template ostream& operator<<(ostream&, _Resetiosflags);
517  extern template ostream& operator<<(ostream&, _Setbase);
518  extern template ostream& operator<<(ostream&, _Setprecision);
519  extern template ostream& operator<<(ostream&, _Setw);
520  extern template istream& operator>>(istream&, _Setfill<char>);
521  extern template istream& operator>>(istream&, _Setiosflags);
522  extern template istream& operator>>(istream&, _Resetiosflags);
523  extern template istream& operator>>(istream&, _Setbase);
524  extern template istream& operator>>(istream&, _Setprecision);
525  extern template istream& operator>>(istream&, _Setw);
526 
527 #ifdef _GLIBCXX_USE_WCHAR_T
528  extern template wostream& operator<<(wostream&, _Setfill<wchar_t>);
529  extern template wostream& operator<<(wostream&, _Setiosflags);
530  extern template wostream& operator<<(wostream&, _Resetiosflags);
531  extern template wostream& operator<<(wostream&, _Setbase);
532  extern template wostream& operator<<(wostream&, _Setprecision);
533  extern template wostream& operator<<(wostream&, _Setw);
534  extern template wistream& operator>>(wistream&, _Setfill<wchar_t>);
535  extern template wistream& operator>>(wistream&, _Setiosflags);
536  extern template wistream& operator>>(wistream&, _Resetiosflags);
537  extern template wistream& operator>>(wistream&, _Setbase);
538  extern template wistream& operator>>(wistream&, _Setprecision);
539  extern template wistream& operator>>(wistream&, _Setw);
540 #endif
541 #endif
542 
543 _GLIBCXX_END_NAMESPACE_VERSION
544 } // namespace
545 
546 #endif /* _GLIBCXX_IOMANIP */