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The C and C++ Include Header Files

/usr/include/c++/11/ext/string_conversions.h


$ cat -n /usr/include/c++/11/ext/string_conversions.h

     1	// String Conversions -*- C++ -*-
     2	
     3	// Copyright (C) 2008-2021 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 ext/string_conversions.h
    26	 *  This file is a GNU extension to the Standard C++ Library.
    27	 */
    28	
    29	#ifndef _STRING_CONVERSIONS_H
    30	#define _STRING_CONVERSIONS_H 1
    31	
    32	#pragma GCC system_header
    33	
    34	#if __cplusplus < 201103L
    35	# include <bits/c++0x_warning.h>
    36	#else
    37	
    38	#include <bits/c++config.h>
    39	#include <ext/numeric_traits.h>
    40	#include <bits/functexcept.h>
    41	#include <cstdlib>
    42	#include <cwchar>
    43	#include <cstdio>
    44	#include <cerrno>
    45	
    46	namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
    47	{
    48	_GLIBCXX_BEGIN_NAMESPACE_VERSION
    49	
    50	  // Helper for all the sto* functions.
    51	  template<typename _TRet, typename _Ret = _TRet, typename _CharT,
    52		   typename... _Base>
    53	    _Ret
    54	    __stoa(_TRet (*__convf) (const _CharT*, _CharT**, _Base...),
    55		   const char* __name, const _CharT* __str, std::size_t* __idx,
    56		   _Base... __base)
    57	    {
    58	      _Ret __ret;
    59	
    60	      _CharT* __endptr;
    61	
    62	      struct _Save_errno {
    63		_Save_errno() : _M_errno(errno) { errno = 0; }
    64		~_Save_errno() { if (errno == 0) errno = _M_errno; }
    65		int _M_errno;
    66	      } const __save_errno;
    67	
    68	      struct _Range_chk {
    69		  static bool
    70		  _S_chk(_TRet, std::false_type) { return false; }
    71	
    72		  static bool
    73		  _S_chk(_TRet __val, std::true_type) // only called when _Ret is int
    74		  {
    75		    return __val < _TRet(__numeric_traits<int>::__min)
    76		      || __val > _TRet(__numeric_traits<int>::__max);
    77		  }
    78	      };
    79	
    80	      const _TRet __tmp = __convf(__str, &__endptr, __base...);
    81	
    82	      if (__endptr == __str)
    83		std::__throw_invalid_argument(__name);
    84	      else if (errno == ERANGE
    85		  || _Range_chk::_S_chk(__tmp, std::is_same<_Ret, int>{}))
    86		std::__throw_out_of_range(__name);
    87	      else
    88		__ret = __tmp;
    89	
    90	      if (__idx)
    91		*__idx = __endptr - __str;
    92	
    93	      return __ret;
    94	    }
    95	
    96	  // Helper for the to_string / to_wstring functions.
    97	  template<typename _String, typename _CharT = typename _String::value_type>
    98	    _String
    99	    __to_xstring(int (*__convf) (_CharT*, std::size_t, const _CharT*,
   100					 __builtin_va_list), std::size_t __n,
   101			 const _CharT* __fmt, ...)
   102	    {
   103	      // XXX Eventually the result should be constructed in-place in
   104	      // the __cxx11 string, likely with the help of internal hooks.
   105	      _CharT* __s = static_cast<_CharT*>(__builtin_alloca(sizeof(_CharT)
   106								  * __n));
   107	
   108	      __builtin_va_list __args;
   109	      __builtin_va_start(__args, __fmt);
   110	
   111	      const int __len = __convf(__s, __n, __fmt, __args);
   112	
   113	      __builtin_va_end(__args);
   114	
   115	      return _String(__s, __s + __len);
   116	    }
   117	
   118	_GLIBCXX_END_NAMESPACE_VERSION
   119	} // namespace
   120	
   121	#endif // C++11
   122	
   123	#endif // _STRING_CONVERSIONS_H