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The C and C++ Include Header Files

cat -n /usr/include/c++/15/bits/streambuf.tcc

     1	// Stream buffer classes -*- C++ -*-
     2	
     3	// Copyright (C) 1997-2025 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/streambuf.tcc
    26	 *  This is an internal header file, included by other library headers.
    27	 *  Do not attempt to use it directly. @headername{streambuf}
    28	 */
    29	
    30	//
    31	// ISO C++ 14882: 27.5  Stream buffers
    32	//
    33	
    34	#ifndef _STREAMBUF_TCC
    35	#define _STREAMBUF_TCC 1
    36	
    37	#ifdef _GLIBCXX_SYSHDR
    38	#pragma GCC system_header
    39	#endif
    40	
    41	#pragma GCC diagnostic push
    42	#pragma GCC diagnostic ignored "-Wc++11-extensions" // extern template
    43	
    44	namespace std _GLIBCXX_VISIBILITY(default)
    45	{
    46	_GLIBCXX_BEGIN_NAMESPACE_VERSION
    47	
    48	  template<typename _CharT, typename _Traits>
    49	    streamsize
    50	    basic_streambuf<_CharT, _Traits>::
    51	    xsgetn(char_type* __s, streamsize __n)
    52	    {
    53	      streamsize __ret = 0;
    54	      while (__ret < __n)
    55		{
    56		  const streamsize __buf_len = this->egptr() - this->gptr();
    57		  if (__buf_len)
    58		    {
    59		      const streamsize __remaining = __n - __ret;
    60		      const streamsize __len = std::min(__buf_len, __remaining);
    61		      traits_type::copy(__s, this->gptr(), __len);
    62		      __ret += __len;
    63		      __s += __len;
    64		      this->__safe_gbump(__len);
    65		    }
    66	
    67		  if (__ret < __n)
    68		    {
    69		      const int_type __c = this->uflow();
    70		      if (!traits_type::eq_int_type(__c, traits_type::eof()))
    71			{
    72			  traits_type::assign(*__s++, traits_type::to_char_type(__c));
    73			  ++__ret;
    74			}
    75		      else
    76			break;
    77		    }
    78		}
    79	      return __ret;
    80	    }
    81	
    82	  template<typename _CharT, typename _Traits>
    83	    streamsize
    84	    basic_streambuf<_CharT, _Traits>::
    85	    xsputn(const char_type* __s, streamsize __n)
    86	    {
    87	      streamsize __ret = 0;
    88	      while (__ret < __n)
    89		{
    90		  const streamsize __buf_len = this->epptr() - this->pptr();
    91		  if (__buf_len)
    92		    {
    93		      const streamsize __remaining = __n - __ret;
    94		      const streamsize __len = std::min(__buf_len, __remaining);
    95		      traits_type::copy(this->pptr(), __s, __len);
    96		      __ret += __len;
    97		      __s += __len;
    98		      this->__safe_pbump(__len);
    99		    }
   100	
   101		  if (__ret < __n)
   102		    {
   103		      int_type __c = this->overflow(traits_type::to_int_type(*__s));
   104		      if (!traits_type::eq_int_type(__c, traits_type::eof()))
   105			{
   106			  ++__ret;
   107			  ++__s;
   108			}
   109		      else
   110			break;
   111		    }
   112		}
   113	      return __ret;
   114	    }
   115	
   116	  // Conceivably, this could be used to implement buffer-to-buffer
   117	  // copies, if this was ever desired in an un-ambiguous way by the
   118	  // standard.
   119	  template<typename _CharT, typename _Traits>
   120	    streamsize
   121	    __copy_streambufs_eof(basic_streambuf<_CharT, _Traits>* __sbin,
   122				  basic_streambuf<_CharT, _Traits>* __sbout,
   123				  bool& __ineof)
   124	    {
   125	      streamsize __ret = 0;
   126	      __ineof = true;
   127	      typename _Traits::int_type __c = __sbin->sgetc();
   128	      while (!_Traits::eq_int_type(__c, _Traits::eof()))
   129		{
   130		  __c = __sbout->sputc(_Traits::to_char_type(__c));
   131		  if (_Traits::eq_int_type(__c, _Traits::eof()))
   132		    {
   133		      __ineof = false;
   134		      break;
   135		    }
   136		  ++__ret;
   137		  __c = __sbin->snextc();
   138		}
   139	      return __ret;
   140	    }
   141	
   142	  template<typename _CharT, typename _Traits>
   143	    inline streamsize
   144	    __copy_streambufs(basic_streambuf<_CharT, _Traits>* __sbin,
   145			      basic_streambuf<_CharT, _Traits>* __sbout)
   146	    {
   147	      bool __ineof;
   148	      return __copy_streambufs_eof(__sbin, __sbout, __ineof);
   149	    }
   150	
   151	  // Inhibit implicit instantiations for required instantiations,
   152	  // which are defined via explicit instantiations elsewhere.
   153	#if _GLIBCXX_EXTERN_TEMPLATE
   154	  extern template class basic_streambuf<char>;
   155	
   156	  extern template
   157	    streamsize
   158	    __copy_streambufs(basic_streambuf<char>*,
   159			      basic_streambuf<char>*);
   160	
   161	#ifdef _GLIBCXX_USE_WCHAR_T
   162	  extern template class basic_streambuf<wchar_t>;
   163	
   164	  extern template
   165	    streamsize
   166	    __copy_streambufs(basic_streambuf<wchar_t>*,
   167			      basic_streambuf<wchar_t>*);
   168	#endif
   169	#endif
   170	
   171	_GLIBCXX_END_NAMESPACE_VERSION
   172	} // namespace std
   173	
   174	#pragma GCC diagnostic pop
   175	#endif