libstdc++
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00001 // String based streams -*- C++ -*- 00002 00003 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 00004 // 2006, 2007, 2008, 2009, 2010, 2011 00005 // Free Software Foundation, Inc. 00006 // 00007 // This file is part of the GNU ISO C++ Library. This library is free 00008 // software; you can redistribute it and/or modify it under the 00009 // terms of the GNU General Public License as published by the 00010 // Free Software Foundation; either version 3, or (at your option) 00011 // any later version. 00012 00013 // This library is distributed in the hope that it will be useful, 00014 // but WITHOUT ANY WARRANTY; without even the implied warranty of 00015 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 00016 // GNU General Public License for more details. 00017 00018 // Under Section 7 of GPL version 3, you are granted additional 00019 // permissions described in the GCC Runtime Library Exception, version 00020 // 3.1, as published by the Free Software Foundation. 00021 00022 // You should have received a copy of the GNU General Public License and 00023 // a copy of the GCC Runtime Library Exception along with this program; 00024 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 00025 // <http://www.gnu.org/licenses/>. 00026 00027 /** @file bits/sstream.tcc 00028 * This is an internal header file, included by other library headers. 00029 * Do not attempt to use it directly. @headername{sstream} 00030 */ 00031 00032 // 00033 // ISO C++ 14882: 27.7 String-based streams 00034 // 00035 00036 #ifndef _SSTREAM_TCC 00037 #define _SSTREAM_TCC 1 00038 00039 #pragma GCC system_header 00040 00041 namespace std _GLIBCXX_VISIBILITY(default) 00042 { 00043 _GLIBCXX_BEGIN_NAMESPACE_VERSION 00044 00045 template <class _CharT, class _Traits, class _Alloc> 00046 typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type 00047 basic_stringbuf<_CharT, _Traits, _Alloc>:: 00048 pbackfail(int_type __c) 00049 { 00050 int_type __ret = traits_type::eof(); 00051 if (this->eback() < this->gptr()) 00052 { 00053 // Try to put back __c into input sequence in one of three ways. 00054 // Order these tests done in is unspecified by the standard. 00055 const bool __testeof = traits_type::eq_int_type(__c, __ret); 00056 if (!__testeof) 00057 { 00058 const bool __testeq = traits_type::eq(traits_type:: 00059 to_char_type(__c), 00060 this->gptr()[-1]); 00061 const bool __testout = this->_M_mode & ios_base::out; 00062 if (__testeq || __testout) 00063 { 00064 this->gbump(-1); 00065 if (!__testeq) 00066 *this->gptr() = traits_type::to_char_type(__c); 00067 __ret = __c; 00068 } 00069 } 00070 else 00071 { 00072 this->gbump(-1); 00073 __ret = traits_type::not_eof(__c); 00074 } 00075 } 00076 return __ret; 00077 } 00078 00079 template <class _CharT, class _Traits, class _Alloc> 00080 typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type 00081 basic_stringbuf<_CharT, _Traits, _Alloc>:: 00082 overflow(int_type __c) 00083 { 00084 const bool __testout = this->_M_mode & ios_base::out; 00085 if (__builtin_expect(!__testout, false)) 00086 return traits_type::eof(); 00087 00088 const bool __testeof = traits_type::eq_int_type(__c, traits_type::eof()); 00089 if (__builtin_expect(__testeof, false)) 00090 return traits_type::not_eof(__c); 00091 00092 const __size_type __capacity = _M_string.capacity(); 00093 const __size_type __max_size = _M_string.max_size(); 00094 const bool __testput = this->pptr() < this->epptr(); 00095 if (__builtin_expect(!__testput && __capacity == __max_size, false)) 00096 return traits_type::eof(); 00097 00098 // Try to append __c into output sequence in one of two ways. 00099 // Order these tests done in is unspecified by the standard. 00100 const char_type __conv = traits_type::to_char_type(__c); 00101 if (!__testput) 00102 { 00103 // NB: Start ostringstream buffers at 512 chars. This is an 00104 // experimental value (pronounced "arbitrary" in some of the 00105 // hipper English-speaking countries), and can be changed to 00106 // suit particular needs. 00107 // 00108 // _GLIBCXX_RESOLVE_LIB_DEFECTS 00109 // 169. Bad efficiency of overflow() mandated 00110 // 432. stringbuf::overflow() makes only one write position 00111 // available 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 __tmp.push_back(__conv); 00120 _M_string.swap(__tmp); 00121 _M_sync(const_cast<char_type*>(_M_string.data()), 00122 this->gptr() - this->eback(), this->pptr() - this->pbase()); 00123 } 00124 else 00125 *this->pptr() = __conv; 00126 this->pbump(1); 00127 return __c; 00128 } 00129 00130 template <class _CharT, class _Traits, class _Alloc> 00131 typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type 00132 basic_stringbuf<_CharT, _Traits, _Alloc>:: 00133 underflow() 00134 { 00135 int_type __ret = traits_type::eof(); 00136 const bool __testin = this->_M_mode & ios_base::in; 00137 if (__testin) 00138 { 00139 // Update egptr() to match the actual string end. 00140 _M_update_egptr(); 00141 00142 if (this->gptr() < this->egptr()) 00143 __ret = traits_type::to_int_type(*this->gptr()); 00144 } 00145 return __ret; 00146 } 00147 00148 template <class _CharT, class _Traits, class _Alloc> 00149 typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type 00150 basic_stringbuf<_CharT, _Traits, _Alloc>:: 00151 seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __mode) 00152 { 00153 pos_type __ret = pos_type(off_type(-1)); 00154 bool __testin = (ios_base::in & this->_M_mode & __mode) != 0; 00155 bool __testout = (ios_base::out & this->_M_mode & __mode) != 0; 00156 const bool __testboth = __testin && __testout && __way != ios_base::cur; 00157 __testin &= !(__mode & ios_base::out); 00158 __testout &= !(__mode & ios_base::in); 00159 00160 // _GLIBCXX_RESOLVE_LIB_DEFECTS 00161 // 453. basic_stringbuf::seekoff need not always fail for an empty stream. 00162 const char_type* __beg = __testin ? this->eback() : this->pbase(); 00163 if ((__beg || !__off) && (__testin || __testout || __testboth)) 00164 { 00165 _M_update_egptr(); 00166 00167 off_type __newoffi = __off; 00168 off_type __newoffo = __newoffi; 00169 if (__way == ios_base::cur) 00170 { 00171 __newoffi += this->gptr() - __beg; 00172 __newoffo += this->pptr() - __beg; 00173 } 00174 else if (__way == ios_base::end) 00175 __newoffo = __newoffi += this->egptr() - __beg; 00176 00177 if ((__testin || __testboth) 00178 && __newoffi >= 0 00179 && this->egptr() - __beg >= __newoffi) 00180 { 00181 this->setg(this->eback(), this->eback() + __newoffi, 00182 this->egptr()); 00183 __ret = pos_type(__newoffi); 00184 } 00185 if ((__testout || __testboth) 00186 && __newoffo >= 0 00187 && this->egptr() - __beg >= __newoffo) 00188 { 00189 _M_pbump(this->pbase(), this->epptr(), __newoffo); 00190 __ret = pos_type(__newoffo); 00191 } 00192 } 00193 return __ret; 00194 } 00195 00196 template <class _CharT, class _Traits, class _Alloc> 00197 typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type 00198 basic_stringbuf<_CharT, _Traits, _Alloc>:: 00199 seekpos(pos_type __sp, ios_base::openmode __mode) 00200 { 00201 pos_type __ret = pos_type(off_type(-1)); 00202 const bool __testin = (ios_base::in & this->_M_mode & __mode) != 0; 00203 const bool __testout = (ios_base::out & this->_M_mode & __mode) != 0; 00204 00205 const char_type* __beg = __testin ? this->eback() : this->pbase(); 00206 if ((__beg || !off_type(__sp)) && (__testin || __testout)) 00207 { 00208 _M_update_egptr(); 00209 00210 const off_type __pos(__sp); 00211 const bool __testpos = (0 <= __pos 00212 && __pos <= this->egptr() - __beg); 00213 if (__testpos) 00214 { 00215 if (__testin) 00216 this->setg(this->eback(), this->eback() + __pos, 00217 this->egptr()); 00218 if (__testout) 00219 _M_pbump(this->pbase(), this->epptr(), __pos); 00220 __ret = __sp; 00221 } 00222 } 00223 return __ret; 00224 } 00225 00226 template <class _CharT, class _Traits, class _Alloc> 00227 void 00228 basic_stringbuf<_CharT, _Traits, _Alloc>:: 00229 _M_sync(char_type* __base, __size_type __i, __size_type __o) 00230 { 00231 const bool __testin = _M_mode & ios_base::in; 00232 const bool __testout = _M_mode & ios_base::out; 00233 char_type* __endg = __base + _M_string.size(); 00234 char_type* __endp = __base + _M_string.capacity(); 00235 00236 if (__base != _M_string.data()) 00237 { 00238 // setbuf: __i == size of buffer area (_M_string.size() == 0). 00239 __endg += __i; 00240 __i = 0; 00241 __endp = __endg; 00242 } 00243 00244 if (__testin) 00245 this->setg(__base, __base + __i, __endg); 00246 if (__testout) 00247 { 00248 _M_pbump(__base, __endp, __o); 00249 // egptr() always tracks the string end. When !__testin, 00250 // for the correct functioning of the streambuf inlines 00251 // the other get area pointers are identical. 00252 if (!__testin) 00253 this->setg(__endg, __endg, __endg); 00254 } 00255 } 00256 00257 template <class _CharT, class _Traits, class _Alloc> 00258 void 00259 basic_stringbuf<_CharT, _Traits, _Alloc>:: 00260 _M_pbump(char_type* __pbeg, char_type* __pend, off_type __off) 00261 { 00262 this->setp(__pbeg, __pend); 00263 while (__off > __gnu_cxx::__numeric_traits<int>::__max) 00264 { 00265 this->pbump(__gnu_cxx::__numeric_traits<int>::__max); 00266 __off -= __gnu_cxx::__numeric_traits<int>::__max; 00267 } 00268 this->pbump(__off); 00269 } 00270 00271 // Inhibit implicit instantiations for required instantiations, 00272 // which are defined via explicit instantiations elsewhere. 00273 #if _GLIBCXX_EXTERN_TEMPLATE 00274 extern template class basic_stringbuf<char>; 00275 extern template class basic_istringstream<char>; 00276 extern template class basic_ostringstream<char>; 00277 extern template class basic_stringstream<char>; 00278 00279 #ifdef _GLIBCXX_USE_WCHAR_T 00280 extern template class basic_stringbuf<wchar_t>; 00281 extern template class basic_istringstream<wchar_t>; 00282 extern template class basic_ostringstream<wchar_t>; 00283 extern template class basic_stringstream<wchar_t>; 00284 #endif 00285 #endif 00286 00287 _GLIBCXX_END_NAMESPACE_VERSION 00288 } // namespace std 00289 00290 #endif