# sstream.tcc

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    00001 // String based streams -*- C++ -*-
    00002
    00003 // Copyright (C) 1997, 1998, 1999, 2001, 2002, 2003, 2004
    00004 // Free Software Foundation, Inc.
    00005 //
    00006 // This file is part of the GNU ISO C++ Library.  This library is free
    00007 // software; you can redistribute it and/or modify it under the
    00008 // terms of the GNU General Public License as published by the
    00009 // Free Software Foundation; either version 2, or (at your option)
    00010 // any later version.
    00011
    00012 // This library is distributed in the hope that it will be useful,
    00013 // but WITHOUT ANY WARRANTY; without even the implied warranty of
    00014 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    00015 // GNU General Public License for more details.
    00016
    00017 // You should have received a copy of the GNU General Public License along
    00018 // with this library; see the file COPYING.  If not, write to the Free
    00019 // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
    00020 // USA.
    00021
    00022 // As a special exception, you may use this file as part of a free software
    00023 // library without restriction.  Specifically, if other files instantiate
    00024 // templates or use macros or inline functions from this file, or you compile
    00025 // this file and link it with other files to produce an executable, this
    00026 // file does not by itself cause the resulting executable to be covered by
    00027 // the GNU General Public License.  This exception does not however
    00028 // invalidate any other reasons why the executable file might be covered by
    00029 // the GNU General Public License.
    00030
    00031 /** @file sstream.tcc
    00032  *  This is an internal header file, included by other library headers.
    00033  *  You should not attempt to use it directly.
    00034  */
    00035
    00036 //
    00037 // ISO C++ 14882: 27.7  String-based streams
    00038 //
    00039
    00040 #ifndef _SSTREAM_TCC
    00041 #define _SSTREAM_TCC 1
    00042
    00043 #pragma GCC system_header
    00044
    00045 #include <sstream>
    00046
    00047 namespace std
    00048 {
    00049   template <class _CharT, class _Traits, class _Alloc>
    00050     typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
    00051     basic_stringbuf<_CharT, _Traits, _Alloc>::
    00052     pbackfail(int_type __c)
    00053     {
    00054       int_type __ret = traits_type::eof();
    00055       if (this->eback() < this->gptr())
    00056     {
    00057       // Try to put back __c into input sequence in one of three ways.
    00058       // Order these tests done in is unspecified by the standard.
    00059       const bool __testeof = traits_type::eq_int_type(__c, __ret);
    00060       if (!__testeof)
    00061         {
    00062           const bool __testeq = traits_type::eq(traits_type::
    00063                             to_char_type(__c),
    00064                             this->gptr()[-1]);
    00065           const bool __testout = this->_M_mode & ios_base::out;
    00066           if (__testeq || __testout)
    00067         {
    00068           this->gbump(-1);
    00069           if (!__testeq)
    00070             *this->gptr() = traits_type::to_char_type(__c);
    00071           __ret = __c;
    00072         }
    00073         }
    00074       else
    00075         {
    00076           this->gbump(-1);
    00077           __ret = traits_type::not_eof(__c);
    00078         }
    00079     }
    00080       return __ret;
    00081     }
    00082
    00083   template <class _CharT, class _Traits, class _Alloc>
    00084     typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
    00085     basic_stringbuf<_CharT, _Traits, _Alloc>::
    00086     overflow(int_type __c)
    00087     {
    00088       const bool __testout = this->_M_mode & ios_base::out;
    00089       if (__builtin_expect(!__testout, false))
    00090     return traits_type::eof();
    00091
    00092       const bool __testeof = traits_type::eq_int_type(__c, traits_type::eof());
    00093       if (__builtin_expect(__testeof, false))
    00094     return traits_type::not_eof(__c);
    00095
    00096       const __size_type __capacity = _M_string.capacity();
    00097       const __size_type __max_size = _M_string.max_size();
    00098       const bool __testput = this->pptr() < this->epptr();
    00099       if (__builtin_expect(!__testput && __capacity == __max_size, false))
    00100     return traits_type::eof();
    00101
    00102       // Try to append __c into output sequence in one of two ways.
    00103       // Order these tests done in is unspecified by the standard.
    00104       if (!__testput)
    00105     {
    00106       // NB: Start ostringstream buffers at 512 chars. This is an
    00107       // experimental value (pronounced "arbitrary" in some of the
    00108       // hipper english-speaking countries), and can be changed to
    00109       // suit particular needs.
    00110       // Then, in virtue of DR 169 (TC) we are allowed to grow more
    00111       // than one char.
    00112       const __size_type __opt_len = std::max(__size_type(2 * __capacity),
    00113                          __size_type(512));
    00114       const __size_type __len = std::min(__opt_len, __max_size);
    00115       __string_type __tmp;
    00116       __tmp.reserve(__len);
    00117       if (this->pbase())
    00118         __tmp.assign(this->pbase(), this->epptr() - this->pbase());
    00119       _M_string.swap(__tmp);
    00120       _M_sync(const_cast<char_type*>(_M_string.data()),
    00121           this->gptr() - this->eback(), this->pptr() - this->pbase());
    00122     }
    00123       return this->sputc(traits_type::to_char_type(__c));
    00124     }
    00125
    00126   template <class _CharT, class _Traits, class _Alloc>
    00127     typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
    00128     basic_stringbuf<_CharT, _Traits, _Alloc>::
    00129     underflow()
    00130     {
    00131       int_type __ret = traits_type::eof();
    00132       const bool __testin = this->_M_mode & ios_base::in;
    00133       if (__testin)
    00134     {
    00135       // Update egptr() to match the actual string end.
    00136       _M_update_egptr();
    00137
    00138       if (this->gptr() < this->egptr())
    00139         __ret = traits_type::to_int_type(*this->gptr());
    00140     }
    00141       return __ret;
    00142     }
    00143
    00144   template <class _CharT, class _Traits, class _Alloc>
    00145     typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type
    00146     basic_stringbuf<_CharT, _Traits, _Alloc>::
    00147     seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __mode)
    00148     {
    00149       pos_type __ret =  pos_type(off_type(-1));
    00150       bool __testin = (ios_base::in & this->_M_mode & __mode) != 0;
    00151       bool __testout = (ios_base::out & this->_M_mode & __mode) != 0;
    00152       const bool __testboth = __testin && __testout && __way != ios_base::cur;
    00153       __testin &= !(__mode & ios_base::out);
    00154       __testout &= !(__mode & ios_base::in);
    00155
    00156       // _GLIBCXX_RESOLVE_LIB_DEFECTS
    00157       // 453. basic_stringbuf::seekoff need not always fail for an empty stream.
    00158       const char_type* __beg = __testin ? this->eback() : this->pbase();
    00159       if ((__beg || !__off) && (__testin || __testout || __testboth))
    00160     {
    00161       _M_update_egptr();
    00162
    00163       off_type __newoffi = __off;
    00164       off_type __newoffo = __newoffi;
    00165       if (__way == ios_base::cur)
    00166         {
    00167           __newoffi += this->gptr() - __beg;
    00168           __newoffo += this->pptr() - __beg;
    00169         }
    00170       else if (__way == ios_base::end)
    00171         __newoffo = __newoffi += this->egptr() - __beg;
    00172
    00173       if ((__testin || __testboth)
    00174           && __newoffi >= 0
    00175           && this->egptr() - __beg >= __newoffi)
    00176         {
    00177           this->gbump((__beg + __newoffi) - this->gptr());
    00178           __ret = pos_type(__newoffi);
    00179         }
    00180       if ((__testout || __testboth)
    00181           && __newoffo >= 0
    00182           && this->egptr() - __beg >= __newoffo)
    00183         {
    00184           this->pbump((__beg + __newoffo) - this->pptr());
    00185           __ret = pos_type(__newoffo);
    00186         }
    00187     }
    00188       return __ret;
    00189     }
    00190
    00191   template <class _CharT, class _Traits, class _Alloc>
    00192     typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type
    00193     basic_stringbuf<_CharT, _Traits, _Alloc>::
    00194     seekpos(pos_type __sp, ios_base::openmode __mode)
    00195     {
    00196       pos_type __ret =  pos_type(off_type(-1));
    00197       const bool __testin = (ios_base::in & this->_M_mode & __mode) != 0;
    00198       const bool __testout = (ios_base::out & this->_M_mode & __mode) != 0;
    00199
    00200       const char_type* __beg = __testin ? this->eback() : this->pbase();
    00201       if (__beg && (__testin || __testout))
    00202     {
    00203       _M_update_egptr();
    00204
    00205       const off_type __pos(__sp);
    00206       const bool __testpos = 0 <= __pos
    00207                              && __pos <=  this->egptr() - __beg;
    00208       if (__testpos)
    00209         {
    00210           if (__testin)
    00211         this->gbump((__beg + __pos) - this->gptr());
    00212           if (__testout)
    00213                 this->pbump((__beg + __pos) - this->pptr());
    00214           __ret = __sp;
    00215         }
    00216     }
    00217       return __ret;
    00218     }
    00219
    00220   // Inhibit implicit instantiations for required instantiations,
    00221   // which are defined via explicit instantiations elsewhere.
    00222   // NB:  This syntax is a GNU extension.
    00223 #if _GLIBCXX_EXTERN_TEMPLATE
    00224   extern template class basic_stringbuf<char>;
    00225   extern template class basic_istringstream<char>;
    00226   extern template class basic_ostringstream<char>;
    00227   extern template class basic_stringstream<char>;
    00228
    00229 #ifdef _GLIBCXX_USE_WCHAR_T
    00230   extern template class basic_stringbuf<wchar_t>;
    00231   extern template class basic_istringstream<wchar_t>;
    00232   extern template class basic_ostringstream<wchar_t>;
    00233   extern template class basic_stringstream<wchar_t>;
    00234 #endif
    00235 #endif
    00236 } // namespace std
    00237
    00238 #endif