# sstream.tcc

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    00001 // String based streams -*- C++ -*-
    00002
    00003 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
    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, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
    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 _GLIBCXX_BEGIN_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       const char_type __conv = traits_type::to_char_type(__c);
    00105       if (!__testput)
    00106     {
    00107       // NB: Start ostringstream buffers at 512 chars.  This is an
    00108       // experimental value (pronounced "arbitrary" in some of the
    00109       // hipper english-speaking countries), and can be changed to
    00110       // suit particular needs.
    00111       //
    00112       // _GLIBCXX_RESOLVE_LIB_DEFECTS
    00113       // 169. Bad efficiency of overflow() mandated
    00114       // 432. stringbuf::overflow() makes only one write position
    00115       //      available
    00116       const __size_type __opt_len = std::max(__size_type(2 * __capacity),
    00117                          __size_type(512));
    00118       const __size_type __len = std::min(__opt_len, __max_size);
    00119       __string_type __tmp;
    00120       __tmp.reserve(__len);
    00121       if (this->pbase())
    00122         __tmp.assign(this->pbase(), this->epptr() - this->pbase());
    00123       __tmp.push_back(__conv);
    00124       _M_string.swap(__tmp);
    00125       _M_sync(const_cast<char_type*>(_M_string.data()),
    00126           this->gptr() - this->eback(), this->pptr() - this->pbase());
    00127     }
    00128       else
    00129     *this->pptr() = __conv;
    00130       this->pbump(1);
    00131       return __c;
    00132     }
    00133
    00134   template <class _CharT, class _Traits, class _Alloc>
    00135     typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
    00136     basic_stringbuf<_CharT, _Traits, _Alloc>::
    00137     underflow()
    00138     {
    00139       int_type __ret = traits_type::eof();
    00140       const bool __testin = this->_M_mode & ios_base::in;
    00141       if (__testin)
    00142     {
    00143       // Update egptr() to match the actual string end.
    00144       _M_update_egptr();
    00145
    00146       if (this->gptr() < this->egptr())
    00147         __ret = traits_type::to_int_type(*this->gptr());
    00148     }
    00149       return __ret;
    00150     }
    00151
    00152   template <class _CharT, class _Traits, class _Alloc>
    00153     typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type
    00154     basic_stringbuf<_CharT, _Traits, _Alloc>::
    00155     seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __mode)
    00156     {
    00157       pos_type __ret =  pos_type(off_type(-1));
    00158       bool __testin = (ios_base::in & this->_M_mode & __mode) != 0;
    00159       bool __testout = (ios_base::out & this->_M_mode & __mode) != 0;
    00160       const bool __testboth = __testin && __testout && __way != ios_base::cur;
    00161       __testin &= !(__mode & ios_base::out);
    00162       __testout &= !(__mode & ios_base::in);
    00163
    00164       // _GLIBCXX_RESOLVE_LIB_DEFECTS
    00165       // 453. basic_stringbuf::seekoff need not always fail for an empty stream.
    00166       const char_type* __beg = __testin ? this->eback() : this->pbase();
    00167       if ((__beg || !__off) && (__testin || __testout || __testboth))
    00168     {
    00169       _M_update_egptr();
    00170
    00171       off_type __newoffi = __off;
    00172       off_type __newoffo = __newoffi;
    00173       if (__way == ios_base::cur)
    00174         {
    00175           __newoffi += this->gptr() - __beg;
    00176           __newoffo += this->pptr() - __beg;
    00177         }
    00178       else if (__way == ios_base::end)
    00179         __newoffo = __newoffi += this->egptr() - __beg;
    00180
    00181       if ((__testin || __testboth)
    00182           && __newoffi >= 0
    00183           && this->egptr() - __beg >= __newoffi)
    00184         {
    00185           this->gbump((__beg + __newoffi) - this->gptr());
    00186           __ret = pos_type(__newoffi);
    00187         }
    00188       if ((__testout || __testboth)
    00189           && __newoffo >= 0
    00190           && this->egptr() - __beg >= __newoffo)
    00191         {
    00192           this->pbump((__beg + __newoffo) - this->pptr());
    00193           __ret = pos_type(__newoffo);
    00194         }
    00195     }
    00196       return __ret;
    00197     }
    00198
    00199   template <class _CharT, class _Traits, class _Alloc>
    00200     typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type
    00201     basic_stringbuf<_CharT, _Traits, _Alloc>::
    00202     seekpos(pos_type __sp, ios_base::openmode __mode)
    00203     {
    00204       pos_type __ret =  pos_type(off_type(-1));
    00205       const bool __testin = (ios_base::in & this->_M_mode & __mode) != 0;
    00206       const bool __testout = (ios_base::out & this->_M_mode & __mode) != 0;
    00207
    00208       const char_type* __beg = __testin ? this->eback() : this->pbase();
    00209       if ((__beg || !off_type(__sp)) && (__testin || __testout))
    00210     {
    00211       _M_update_egptr();
    00212
    00213       const off_type __pos(__sp);
    00214       const bool __testpos = (0 <= __pos
    00215                   && __pos <= this->egptr() - __beg);
    00216       if (__testpos)
    00217         {
    00218           if (__testin)
    00219         this->gbump((__beg + __pos) - this->gptr());
    00220           if (__testout)
    00221                 this->pbump((__beg + __pos) - this->pptr());
    00222           __ret = __sp;
    00223         }
    00224     }
    00225       return __ret;
    00226     }
    00227
    00228   template <class _CharT, class _Traits, class _Alloc>
    00229     void
    00230     basic_stringbuf<_CharT, _Traits, _Alloc>::
    00231     _M_sync(char_type* __base, __size_type __i, __size_type __o)
    00232     {
    00233       const bool __testin = _M_mode & ios_base::in;
    00234       const bool __testout = _M_mode & ios_base::out;
    00235       char_type* __endg = __base + _M_string.size();
    00236       char_type* __endp = __base + _M_string.capacity();
    00237
    00238       if (__base != _M_string.data())
    00239     {
    00240       // setbuf: __i == size of buffer area (_M_string.size() == 0).
    00241       __endg += __i;
    00242       __i = 0;
    00243       __endp = __endg;
    00244     }
    00245
    00246       if (__testin)
    00247     this->setg(__base, __base + __i, __endg);
    00248       if (__testout)
    00249     {
    00250       this->setp(__base, __endp);
    00251       this->pbump(__o);
    00252       // egptr() always tracks the string end.  When !__testin,
    00253       // for the correct functioning of the streambuf inlines
    00254       // the other get area pointers are identical.
    00255       if (!__testin)
    00256         this->setg(__endg, __endg, __endg);
    00257     }
    00258     }
    00259
    00260   // Inhibit implicit instantiations for required instantiations,
    00261   // which are defined via explicit instantiations elsewhere.
    00262   // NB:  This syntax is a GNU extension.
    00263 #if _GLIBCXX_EXTERN_TEMPLATE
    00264   extern template class basic_stringbuf<char>;
    00265   extern template class basic_istringstream<char>;
    00266   extern template class basic_ostringstream<char>;
    00267   extern template class basic_stringstream<char>;
    00268
    00269 #ifdef _GLIBCXX_USE_WCHAR_T
    00270   extern template class basic_stringbuf<wchar_t>;
    00271   extern template class basic_istringstream<wchar_t>;
    00272   extern template class basic_ostringstream<wchar_t>;
    00273   extern template class basic_stringstream<wchar_t>;
    00274 #endif
    00275 #endif
    00276
    00277 _GLIBCXX_END_NAMESPACE
    00278
    00279 #endif