1 // String based streams -*- C++ -*- 2 3 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 4 // 2006, 2007, 2008, 2009, 2010, 2011 5 // Free Software Foundation, Inc. 6 // 7 // This file is part of the GNU ISO C++ Library. This library is free 8 // software; you can redistribute it and/or modify it under the 9 // terms of the GNU General Public License as published by the 10 // Free Software Foundation; either version 3, or (at your option) 11 // any later version. 12 13 // This library is distributed in the hope that it will be useful, 14 // but WITHOUT ANY WARRANTY; without even the implied warranty of 15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 // GNU General Public License for more details. 17 18 // Under Section 7 of GPL version 3, you are granted additional 19 // permissions described in the GCC Runtime Library Exception, version 20 // 3.1, as published by the Free Software Foundation. 21 22 // You should have received a copy of the GNU General Public License and 23 // a copy of the GCC Runtime Library Exception along with this program; 24 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 25 // <http://www.gnu.org/licenses/>. 26 27 /** @file bits/sstream.tcc 28 * This is an internal header file, included by other library headers. 29 * Do not attempt to use it directly. @headername{sstream} 30 */ 31 32 // 33 // ISO C++ 14882: 27.7 String-based streams 34 // 35 36 #ifndef _SSTREAM_TCC 37 #define _SSTREAM_TCC 1 38 39 #pragma GCC system_header 40 41 namespace std _GLIBCXX_VISIBILITY(default) 42 { 43 _GLIBCXX_BEGIN_NAMESPACE_VERSION 44 45 template <class _CharT, class _Traits, class _Alloc> 46 typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type 47 basic_stringbuf<_CharT, _Traits, _Alloc>:: 48 pbackfail(int_type __c) 49 { 50 int_type __ret = traits_type::eof(); 51 if (this->eback() < this->gptr()) 52 { 53 // Try to put back __c into input sequence in one of three ways. 54 // Order these tests done in is unspecified by the standard. 55 const bool __testeof = traits_type::eq_int_type(__c, __ret); 56 if (!__testeof) 57 { 58 const bool __testeq = traits_type::eq(traits_type:: 59 to_char_type(__c), 60 this->gptr()[-1]); 61 const bool __testout = this->_M_mode & ios_base::out; 62 if (__testeq || __testout) 63 { 64 this->gbump(-1); 65 if (!__testeq) 66 *this->gptr() = traits_type::to_char_type(__c); 67 __ret = __c; 68 } 69 } 70 else 71 { 72 this->gbump(-1); 73 __ret = traits_type::not_eof(__c); 74 } 75 } 76 return __ret; 77 } 78 79 template <class _CharT, class _Traits, class _Alloc> 80 typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type 81 basic_stringbuf<_CharT, _Traits, _Alloc>:: 82 overflow(int_type __c) 83 { 84 const bool __testout = this->_M_mode & ios_base::out; 85 if (__builtin_expect(!__testout, false)) 86 return traits_type::eof(); 87 88 const bool __testeof = traits_type::eq_int_type(__c, traits_type::eof()); 89 if (__builtin_expect(__testeof, false)) 90 return traits_type::not_eof(__c); 91 92 const __size_type __capacity = _M_string.capacity(); 93 const __size_type __max_size = _M_string.max_size(); 94 const bool __testput = this->pptr() < this->epptr(); 95 if (__builtin_expect(!__testput && __capacity == __max_size, false)) 96 return traits_type::eof(); 97 98 // Try to append __c into output sequence in one of two ways. 99 // Order these tests done in is unspecified by the standard. 100 const char_type __conv = traits_type::to_char_type(__c); 101 if (!__testput) 102 { 103 // NB: Start ostringstream buffers at 512 chars. This is an 104 // experimental value (pronounced "arbitrary" in some of the 105 // hipper English-speaking countries), and can be changed to 106 // suit particular needs. 107 // 108 // _GLIBCXX_RESOLVE_LIB_DEFECTS 109 // 169. Bad efficiency of overflow() mandated 110 // 432. stringbuf::overflow() makes only one write position 111 // available 112 const __size_type __opt_len = std::max(__size_type(2 * __capacity), 113 __size_type(512)); 114 const __size_type __len = std::min(__opt_len, __max_size); 115 __string_type __tmp; 116 __tmp.reserve(__len); 117 if (this->pbase()) 118 __tmp.assign(this->pbase(), this->epptr() - this->pbase()); 119 __tmp.push_back(__conv); 120 _M_string.swap(__tmp); 121 _M_sync(const_cast<char_type*>(_M_string.data()), 122 this->gptr() - this->eback(), this->pptr() - this->pbase()); 123 } 124 else 125 *this->pptr() = __conv; 126 this->pbump(1); 127 return __c; 128 } 129 130 template <class _CharT, class _Traits, class _Alloc> 131 typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type 132 basic_stringbuf<_CharT, _Traits, _Alloc>:: 133 underflow() 134 { 135 int_type __ret = traits_type::eof(); 136 const bool __testin = this->_M_mode & ios_base::in; 137 if (__testin) 138 { 139 // Update egptr() to match the actual string end. 140 _M_update_egptr(); 141 142 if (this->gptr() < this->egptr()) 143 __ret = traits_type::to_int_type(*this->gptr()); 144 } 145 return __ret; 146 } 147 148 template <class _CharT, class _Traits, class _Alloc> 149 typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type 150 basic_stringbuf<_CharT, _Traits, _Alloc>:: 151 seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __mode) 152 { 153 pos_type __ret = pos_type(off_type(-1)); 154 bool __testin = (ios_base::in & this->_M_mode & __mode) != 0; 155 bool __testout = (ios_base::out & this->_M_mode & __mode) != 0; 156 const bool __testboth = __testin && __testout && __way != ios_base::cur; 157 __testin &= !(__mode & ios_base::out); 158 __testout &= !(__mode & ios_base::in); 159 160 // _GLIBCXX_RESOLVE_LIB_DEFECTS 161 // 453. basic_stringbuf::seekoff need not always fail for an empty stream. 162 const char_type* __beg = __testin ? this->eback() : this->pbase(); 163 if ((__beg || !__off) && (__testin || __testout || __testboth)) 164 { 165 _M_update_egptr(); 166 167 off_type __newoffi = __off; 168 off_type __newoffo = __newoffi; 169 if (__way == ios_base::cur) 170 { 171 __newoffi += this->gptr() - __beg; 172 __newoffo += this->pptr() - __beg; 173 } 174 else if (__way == ios_base::end) 175 __newoffo = __newoffi += this->egptr() - __beg; 176 177 if ((__testin || __testboth) 178 && __newoffi >= 0 179 && this->egptr() - __beg >= __newoffi) 180 { 181 this->setg(this->eback(), this->eback() + __newoffi, 182 this->egptr()); 183 __ret = pos_type(__newoffi); 184 } 185 if ((__testout || __testboth) 186 && __newoffo >= 0 187 && this->egptr() - __beg >= __newoffo) 188 { 189 _M_pbump(this->pbase(), this->epptr(), __newoffo); 190 __ret = pos_type(__newoffo); 191 } 192 } 193 return __ret; 194 } 195 196 template <class _CharT, class _Traits, class _Alloc> 197 typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type 198 basic_stringbuf<_CharT, _Traits, _Alloc>:: 199 seekpos(pos_type __sp, ios_base::openmode __mode) 200 { 201 pos_type __ret = pos_type(off_type(-1)); 202 const bool __testin = (ios_base::in & this->_M_mode & __mode) != 0; 203 const bool __testout = (ios_base::out & this->_M_mode & __mode) != 0; 204 205 const char_type* __beg = __testin ? this->eback() : this->pbase(); 206 if ((__beg || !off_type(__sp)) && (__testin || __testout)) 207 { 208 _M_update_egptr(); 209 210 const off_type __pos(__sp); 211 const bool __testpos = (0 <= __pos 212 && __pos <= this->egptr() - __beg); 213 if (__testpos) 214 { 215 if (__testin) 216 this->setg(this->eback(), this->eback() + __pos, 217 this->egptr()); 218 if (__testout) 219 _M_pbump(this->pbase(), this->epptr(), __pos); 220 __ret = __sp; 221 } 222 } 223 return __ret; 224 } 225 226 template <class _CharT, class _Traits, class _Alloc> 227 void 228 basic_stringbuf<_CharT, _Traits, _Alloc>:: 229 _M_sync(char_type* __base, __size_type __i, __size_type __o) 230 { 231 const bool __testin = _M_mode & ios_base::in; 232 const bool __testout = _M_mode & ios_base::out; 233 char_type* __endg = __base + _M_string.size(); 234 char_type* __endp = __base + _M_string.capacity(); 235 236 if (__base != _M_string.data()) 237 { 238 // setbuf: __i == size of buffer area (_M_string.size() == 0). 239 __endg += __i; 240 __i = 0; 241 __endp = __endg; 242 } 243 244 if (__testin) 245 this->setg(__base, __base + __i, __endg); 246 if (__testout) 247 { 248 _M_pbump(__base, __endp, __o); 249 // egptr() always tracks the string end. When !__testin, 250 // for the correct functioning of the streambuf inlines 251 // the other get area pointers are identical. 252 if (!__testin) 253 this->setg(__endg, __endg, __endg); 254 } 255 } 256 257 template <class _CharT, class _Traits, class _Alloc> 258 void 259 basic_stringbuf<_CharT, _Traits, _Alloc>:: 260 _M_pbump(char_type* __pbeg, char_type* __pend, off_type __off) 261 { 262 this->setp(__pbeg, __pend); 263 while (__off > __gnu_cxx::__numeric_traits<int>::__max) 264 { 265 this->pbump(__gnu_cxx::__numeric_traits<int>::__max); 266 __off -= __gnu_cxx::__numeric_traits<int>::__max; 267 } 268 this->pbump(__off); 269 } 270 271 // Inhibit implicit instantiations for required instantiations, 272 // which are defined via explicit instantiations elsewhere. 273 #if _GLIBCXX_EXTERN_TEMPLATE 274 extern template class basic_stringbuf<char>; 275 extern template class basic_istringstream<char>; 276 extern template class basic_ostringstream<char>; 277 extern template class basic_stringstream<char>; 278 279 #ifdef _GLIBCXX_USE_WCHAR_T 280 extern template class basic_stringbuf<wchar_t>; 281 extern template class basic_istringstream<wchar_t>; 282 extern template class basic_ostringstream<wchar_t>; 283 extern template class basic_stringstream<wchar_t>; 284 #endif 285 #endif 286 287 _GLIBCXX_END_NAMESPACE_VERSION 288 } // namespace std 289 290 #endif 291