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The C and C++ Include Header Files

cat -n /usr/include/x86_64-linux-gnu/c++/15/bits/c++locale.h

     1	// Wrapper for underlying C-language localization -*- C++ -*-
     2	
     3	// Copyright (C) 2001-2025 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 bits/c++locale.h
    26	 *  This is an internal header file, included by other library headers.
    27	 *  Do not attempt to use it directly. @headername{locale}
    28	 */
    29	
    30	//
    31	// ISO C++ 14882: 22.8  Standard locale categories.
    32	//
    33	
    34	// Written by Benjamin Kosnik <bkoz@redhat.com>
    35	
    36	#ifndef _GLIBCXX_CXX_LOCALE_H
    37	#define _GLIBCXX_CXX_LOCALE_H 1
    38	
    39	#pragma GCC system_header
    40	
    41	#include <clocale>
    42	
    43	#define _GLIBCXX_C_LOCALE_GNU 1
    44	
    45	#define _GLIBCXX_NUM_CATEGORIES 6
    46	
    47	#if __GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ > 2)
    48	namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
    49	{
    50	_GLIBCXX_BEGIN_NAMESPACE_VERSION
    51	
    52	  extern "C" __typeof(uselocale) __uselocale;
    53	
    54	_GLIBCXX_END_NAMESPACE_VERSION
    55	} // namespace
    56	#endif
    57	
    58	namespace std _GLIBCXX_VISIBILITY(default)
    59	{
    60	_GLIBCXX_BEGIN_NAMESPACE_VERSION
    61	
    62	  typedef __locale_t		__c_locale;
    63	
    64	#if defined _GLIBCXX_LONG_DOUBLE_ALT128_COMPAT \
    65	  && defined __LONG_DOUBLE_IEEE128__
    66	namespace __gnu_cxx_ieee128 {
    67	#endif
    68	
    69	  // Convert numeric value of type double and long double to string and
    70	  // return length of string.  If vsnprintf is available use it, otherwise
    71	  // fall back to the unsafe vsprintf which, in general, can be dangerous
    72	  // and should be avoided.
    73	  inline int
    74	  __convert_from_v(const __c_locale& __cloc __attribute__ ((__unused__)),
    75			   char* __out,
    76			   const int __size __attribute__ ((__unused__)),
    77			   const char* __fmt, ...)
    78	  {
    79	#if __GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ > 2)
    80	    __c_locale __old = __gnu_cxx::__uselocale(__cloc);
    81	#else
    82	    char* __old = std::setlocale(LC_NUMERIC, 0);
    83	    char* __sav = 0;
    84	    if (__builtin_strcmp(__old, "C"))
    85	      {
    86		const size_t __len = __builtin_strlen(__old) + 1;
    87		__sav = new char[__len];
    88		__builtin_memcpy(__sav, __old, __len);
    89		std::setlocale(LC_NUMERIC, "C");
    90	      }
    91	#endif
    92	
    93	    __builtin_va_list __args;
    94	    __builtin_va_start(__args, __fmt);
    95	
    96	#if _GLIBCXX_USE_C99_STDIO
    97	    const int __ret = __builtin_vsnprintf(__out, __size, __fmt, __args);
    98	#else
    99	    const int __ret = __builtin_vsprintf(__out, __fmt, __args);
   100	#endif
   101	
   102	    __builtin_va_end(__args);
   103	
   104	#if __GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ > 2)
   105	    __gnu_cxx::__uselocale(__old);
   106	#else
   107	    if (__sav)
   108	      {
   109		std::setlocale(LC_NUMERIC, __sav);
   110		delete [] __sav;
   111	      }
   112	#endif
   113	    return __ret;
   114	  }
   115	
   116	#if defined _GLIBCXX_LONG_DOUBLE_ALT128_COMPAT \
   117	  && defined __LONG_DOUBLE_IEEE128__
   118	} // namespace __gnu_cxx_ieee128
   119	#endif
   120	
   121	_GLIBCXX_END_NAMESPACE_VERSION
   122	} // namespace
   123	
   124	#endif