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

   1 // Stream buffer classes -*- C++ -*-
   2
   3 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
   4 // 2006, 2009, 2010  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 3, 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 // Under Section 7 of GPL version 3, you are granted additional
  18 // permissions described in the GCC Runtime Library Exception, version
  19 // 3.1, as published by the Free Software Foundation.
  20
  21 // You should have received a copy of the GNU General Public License and
  22 // a copy of the GCC Runtime Library Exception along with this program;
  23 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  24 // <http://www.gnu.org/licenses/>.
  25
  26 /** @file bits/streambuf.tcc
  27  *  This is an internal header file, included by other library headers.
  28  *  Do not attempt to use it directly. @headername{streambuf}
  29  */
  30
  31 //
  32 // ISO C++ 14882: 27.5  Stream buffers
  33 //
  34
  35 #ifndef _STREAMBUF_TCC
  36 #define _STREAMBUF_TCC 1
  37
  38 #pragma GCC system_header
  39
  40 namespace std _GLIBCXX_VISIBILITY(default)
  41 {
  42 _GLIBCXX_BEGIN_NAMESPACE_VERSION
  43
  44   template<typename _CharT, typename _Traits>
  45     streamsize
  46     basic_streambuf<_CharT, _Traits>::
  47     xsgetn(char_type* __s, streamsize __n)
  48     {
  49       streamsize __ret = 0;
  50       while (__ret < __n)
  51         {
  52           const streamsize __buf_len = this->egptr() - this->gptr();
  53           if (__buf_len)
  54             {
  55               const streamsize __remaining = __n - __ret;
  56               const streamsize __len = std::min(__buf_len, __remaining);
  57               traits_type::copy(__s, this->gptr(), __len);
  58               __ret += __len;
  59               __s += __len;
  60               this->gbump(__len);
  61             }
  62
  63           if (__ret < __n)
  64             {
  65               const int_type __c = this->uflow();
  66               if (!traits_type::eq_int_type(__c, traits_type::eof()))
  67                 {
  68                   traits_type::assign(*__s++, traits_type::to_char_type(__c));
  69                   ++__ret;
  70                 }
  71               else
  72                 break;
  73             }
  74         }
  75       return __ret;
  76     }
  77
  78   template<typename _CharT, typename _Traits>
  79     streamsize
  80     basic_streambuf<_CharT, _Traits>::
  81     xsputn(const char_type* __s, streamsize __n)
  82     {
  83       streamsize __ret = 0;
  84       while (__ret < __n)
  85         {
  86           const streamsize __buf_len = this->epptr() - this->pptr();
  87           if (__buf_len)
  88             {
  89               const streamsize __remaining = __n - __ret;
  90               const streamsize __len = std::min(__buf_len, __remaining);
  91               traits_type::copy(this->pptr(), __s, __len);
  92               __ret += __len;
  93               __s += __len;
  94               this->pbump(__len);
  95             }
  96
  97           if (__ret < __n)
  98             {
  99               int_type __c = this->overflow(traits_type::to_int_type(*__s));
 100               if (!traits_type::eq_int_type(__c, traits_type::eof()))
 101                 {
 102                   ++__ret;
 103                   ++__s;
 104                 }
 105               else
 106                 break;
 107             }
 108         }
 109       return __ret;
 110     }
 111
 112   // Conceivably, this could be used to implement buffer-to-buffer
 113   // copies, if this was ever desired in an un-ambiguous way by the
 114   // standard.
 115   template<typename _CharT, typename _Traits>
 116     streamsize
 117     __copy_streambufs_eof(basic_streambuf<_CharT, _Traits>* __sbin,
 118                           basic_streambuf<_CharT, _Traits>* __sbout,
 119                           bool& __ineof)
 120     {
 121       streamsize __ret = 0;
 122       __ineof = true;
 123       typename _Traits::int_type __c = __sbin->sgetc();
 124       while (!_Traits::eq_int_type(__c, _Traits::eof()))
 125         {
 126           __c = __sbout->sputc(_Traits::to_char_type(__c));
 127           if (_Traits::eq_int_type(__c, _Traits::eof()))
 128             {
 129               __ineof = false;
 130               break;
 131             }
 132           ++__ret;
 133           __c = __sbin->snextc();
 134         }
 135       return __ret;
 136     }
 137
 138   template<typename _CharT, typename _Traits>
 139     inline streamsize
 140     __copy_streambufs(basic_streambuf<_CharT, _Traits>* __sbin,
 141                       basic_streambuf<_CharT, _Traits>* __sbout)
 142     {
 143       bool __ineof;
 144       return __copy_streambufs_eof(__sbin, __sbout, __ineof);
 145     }
 146
 147   // Inhibit implicit instantiations for required instantiations,
 148   // which are defined via explicit instantiations elsewhere.
 149   // NB:  This syntax is a GNU extension.
 150 #if _GLIBCXX_EXTERN_TEMPLATE
 151   extern template class basic_streambuf<char>;
 152   extern template
 153     streamsize
 154     __copy_streambufs(basic_streambuf<char>*,
 155                       basic_streambuf<char>*);
 156   extern template
 157     streamsize
 158     __copy_streambufs_eof(basic_streambuf<char>*,
 159                           basic_streambuf<char>*, bool&);
 160
 161 #ifdef _GLIBCXX_USE_WCHAR_T
 162   extern template class basic_streambuf<wchar_t>;
 163   extern template
 164     streamsize
 165     __copy_streambufs(basic_streambuf<wchar_t>*,
 166                       basic_streambuf<wchar_t>*);
 167   extern template
 168     streamsize
 169     __copy_streambufs_eof(basic_streambuf<wchar_t>*,
 170                           basic_streambuf<wchar_t>*, bool&);
 171 #endif
 172 #endif
 173
 174 _GLIBCXX_END_NAMESPACE_VERSION
 175 } // namespace
 176
 177 #endif