libstdc++-v3/include/bits/streambuf.tcc

   1 // Stream buffer classes -*- C++ -*-
   2
   3 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004
   4 // Free Software Foundation, Inc.
   5 //
   6 // This file is part of the GNU ISO C++ Library.  This library is free
   7 // software; you can redistribute it and/or modify it under the
   8 // terms of the GNU General Public License as published by the
   9 // Free Software Foundation; either version 2, or (at your option)
  10 // any later version.
  11
  12 // This library is distributed in the hope that it will be useful,
  13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 // GNU General Public License for more details.
  16
  17 // You should have received a copy of the GNU General Public License along
  18 // with this library; see the file COPYING.  If not, write to the Free
  19 // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
  20 // USA.
  21
  22 // As a special exception, you may use this file as part of a free software
  23 // library without restriction.  Specifically, if other files instantiate
  24 // templates or use macros or inline functions from this file, or you compile
  25 // this file and link it with other files to produce an executable, this
  26 // file does not by itself cause the resulting executable to be covered by
  27 // the GNU General Public License.  This exception does not however
  28 // invalidate any other reasons why the executable file might be covered by
  29 // the GNU General Public License.
  30
  31 /** @file streambuf.tcc
  32  *  This is an internal header file, included by other library headers.
  33  *  You should not attempt to use it directly.
  34  */
  35
  36 //
  37 // ISO C++ 14882: 27.5  Stream buffers
  38 //
  39
  40 #ifndef _STREAMBUF_TCC
  41 #define _STREAMBUF_TCC 1
  42
  43 #pragma GCC system_header
  44
  45 namespace std
  46 {
  47   template<typename _CharT, typename _Traits>
  48     streamsize
  49     basic_streambuf<_CharT, _Traits>::
  50     xsgetn(char_type* __s, streamsize __n)
  51     {
  52       streamsize __ret = 0;
  53       while (__ret < __n)
  54         {
  55           const size_t __buf_len = this->egptr() - this->gptr();
  56           if (__buf_len)
  57             {
  58               const size_t __remaining = __n - __ret;
  59               const size_t __len = std::min(__buf_len, __remaining);
  60               traits_type::copy(__s, this->gptr(), __len);
  61               __ret += __len;
  62               __s += __len;
  63               this->gbump(__len);
  64             }
  65
  66           if (__ret < __n)
  67             {
  68               const int_type __c = this->uflow();
  69               if (!traits_type::eq_int_type(__c, traits_type::eof()))
  70                 {
  71                   traits_type::assign(*__s++, traits_type::to_char_type(__c));
  72                   ++__ret;
  73                 }
  74               else
  75                 break;
  76             }
  77         }
  78       return __ret;
  79     }
  80
  81   template<typename _CharT, typename _Traits>
  82     streamsize
  83     basic_streambuf<_CharT, _Traits>::
  84     xsputn(const char_type* __s, streamsize __n)
  85     {
  86       streamsize __ret = 0;
  87       while (__ret < __n)
  88         {
  89           const size_t __buf_len = this->epptr() - this->pptr();
  90           if (__buf_len)
  91             {
  92               const size_t __remaining = __n - __ret;
  93               const size_t __len = std::min(__buf_len, __remaining);
  94               traits_type::copy(this->pptr(), __s, __len);
  95               __ret += __len;
  96               __s += __len;
  97               this->pbump(__len);
  98             }
  99
 100           if (__ret < __n)
 101             {
 102               int_type __c = this->overflow(traits_type::to_int_type(*__s));
 103               if (!traits_type::eq_int_type(__c, traits_type::eof()))
 104                 {
 105                   ++__ret;
 106                   ++__s;
 107                 }
 108               else
 109                 break;
 110             }
 111         }
 112       return __ret;
 113     }
 114
 115   // Conceivably, this could be used to implement buffer-to-buffer
 116   // copies, if this was ever desired in an un-ambiguous way by the
 117   // standard.
 118   template<typename _CharT, typename _Traits>
 119     streamsize
 120     __copy_streambufs(basic_streambuf<_CharT, _Traits>* __sbin,
 121                       basic_streambuf<_CharT, _Traits>* __sbout)
 122     {
 123       streamsize __ret = 0;
 124       typename _Traits::int_type __c = __sbin->sgetc();
 125       while (!_Traits::eq_int_type(__c, _Traits::eof()))
 126         {
 127           __c = __sbout->sputc(_Traits::to_char_type(__c));
 128           if (_Traits::eq_int_type(__c, _Traits::eof()))
 129             break;
 130           ++__ret;
 131           __c = __sbin->snextc();
 132         }
 133       return __ret;
 134     }
 135
 136   // Inhibit implicit instantiations for required instantiations,
 137   // which are defined via explicit instantiations elsewhere.
 138   // NB:  This syntax is a GNU extension.
 139 #if _GLIBCXX_EXTERN_TEMPLATE
 140   extern template class basic_streambuf<char>;
 141   extern template
 142     streamsize
 143     __copy_streambufs(basic_streambuf<char>*, basic_streambuf<char>*);
 144
 145 #ifdef _GLIBCXX_USE_WCHAR_T
 146   extern template class basic_streambuf<wchar_t>;
 147   extern template
 148     streamsize
 149     __copy_streambufs(basic_streambuf<wchar_t>*, basic_streambuf<wchar_t>*);
 150 #endif
 151 #endif
 152 } // namespace std
 153
 154 #endif