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The C and C++ Include Header Files
cat -n /usr/include/c++/15/bits/sstream.tcc
1 // String based streams -*- C++ -*- 2 3 // Copyright (C) 1997-2025 Free Software Foundation, Inc. 4 // 5 // This file is part of the GNU ISO C++ Library. This library is free 6 // software; you can redistribute it and/or modify it under the 7 // terms of the GNU General Public License as published by the 8 // Free Software Foundation; either version 3, or (at your option) 9 // any later version. 10 11 // This library is distributed in the hope that it will be useful, 12 // but WITHOUT ANY WARRANTY; without even the implied warranty of 13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 // GNU General Public License for more details. 15 16 // Under Section 7 of GPL version 3, you are granted additional 17 // permissions described in the GCC Runtime Library Exception, version 18 // 3.1, as published by the Free Software Foundation. 19 20 // You should have received a copy of the GNU General Public License and 21 // a copy of the GCC Runtime Library Exception along with this program; 22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 23 // <http://www.gnu.org/licenses/>. 24 25 /** @file bits/sstream.tcc 26 * This is an internal header file, included by other library headers. 27 * Do not attempt to use it directly. @headername{sstream} 28 */ 29 30 // 31 // ISO C++ 14882: 27.7 String-based streams 32 // 33 34 #ifndef _SSTREAM_TCC 35 #define _SSTREAM_TCC 1 36 37 #ifdef _GLIBCXX_SYSHDR 38 #pragma GCC system_header 39 #endif 40 #pragma GCC diagnostic push 41 #pragma GCC diagnostic ignored "-Wc++11-extensions" // extern template 42 43 namespace std _GLIBCXX_VISIBILITY(default) 44 { 45 _GLIBCXX_BEGIN_NAMESPACE_VERSION 46 47 template <class _CharT, class _Traits, class _Alloc> 48 typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type 49 basic_stringbuf<_CharT, _Traits, _Alloc>:: 50 pbackfail(int_type __c) 51 { 52 int_type __ret = traits_type::eof(); 53 if (this->eback() < this->gptr()) 54 { 55 // Try to put back __c into input sequence in one of three ways. 56 // Order these tests done in is unspecified by the standard. 57 const bool __testeof = traits_type::eq_int_type(__c, __ret); 58 if (!__testeof) 59 { 60 const bool __testeq = traits_type::eq(traits_type:: 61 to_char_type(__c), 62 this->gptr()[-1]); 63 const bool __testout = this->_M_mode & ios_base::out; 64 if (__testeq || __testout) 65 { 66 this->gbump(-1); 67 if (!__testeq) 68 *this->gptr() = traits_type::to_char_type(__c); 69 __ret = __c; 70 } 71 } 72 else 73 { 74 this->gbump(-1); 75 __ret = traits_type::not_eof(__c); 76 } 77 } 78 return __ret; 79 } 80 81 template <class _CharT, class _Traits, class _Alloc> 82 typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type 83 basic_stringbuf<_CharT, _Traits, _Alloc>:: 84 overflow(int_type __c) 85 { 86 const bool __testout = this->_M_mode & ios_base::out; 87 if (__builtin_expect(!__testout, false)) 88 return traits_type::eof(); 89 90 const bool __testeof = traits_type::eq_int_type(__c, traits_type::eof()); 91 if (__builtin_expect(__testeof, false)) 92 return traits_type::not_eof(__c); 93 94 const __size_type __capacity = _M_string.capacity(); 95 96 #if _GLIBCXX_USE_CXX11_ABI 97 if (size_t(this->epptr() - this->pbase()) < __capacity) 98 { 99 // There is additional capacity in _M_string that can be used. 100 char_type* __base = const_cast<char_type*>(_M_string.data()); 101 _M_pbump(__base, __base + __capacity, this->pptr() - this->pbase()); 102 if (_M_mode & ios_base::in) 103 { 104 const __size_type __nget = this->gptr() - this->eback(); 105 const __size_type __eget = this->egptr() - this->eback(); 106 this->setg(__base, __base + __nget, __base + __eget + 1); 107 } 108 *this->pptr() = traits_type::to_char_type(__c); 109 this->pbump(1); 110 return __c; 111 } 112 #endif 113 114 const __size_type __max_size = _M_string.max_size(); 115 const bool __testput = this->pptr() < this->epptr(); 116 if (__builtin_expect(!__testput && __capacity == __max_size, false)) 117 return traits_type::eof(); 118 119 // Try to append __c into output sequence in one of two ways. 120 // Order these tests done in is unspecified by the standard. 121 const char_type __conv = traits_type::to_char_type(__c); 122 if (!__testput) 123 { 124 // NB: Start ostringstream buffers at 512 chars. This is an 125 // experimental value (pronounced "arbitrary" in some of the 126 // hipper English-speaking countries), and can be changed to 127 // suit particular needs. 128 // 129 // _GLIBCXX_RESOLVE_LIB_DEFECTS 130 // 169. Bad efficiency of overflow() mandated 131 // 432. stringbuf::overflow() makes only one write position 132 // available 133 const __size_type __opt_len = std::max(__size_type(2 * __capacity), 134 __size_type(512)); 135 const __size_type __len = std::min(__opt_len, __max_size); 136 __string_type __tmp(_M_string.get_allocator()); 137 __tmp.reserve(__len); 138 if (this->pbase()) 139 __tmp.assign(this->pbase(), this->epptr() - this->pbase()); 140 __tmp.push_back(__conv); 141 _M_string.swap(__tmp); 142 _M_sync(const_cast<char_type*>(_M_string.data()), 143 this->gptr() - this->eback(), this->pptr() - this->pbase()); 144 } 145 else 146 *this->pptr() = __conv; 147 this->pbump(1); 148 return __c; 149 } 150 151 template <class _CharT, class _Traits, class _Alloc> 152 typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type 153 basic_stringbuf<_CharT, _Traits, _Alloc>:: 154 underflow() 155 { 156 int_type __ret = traits_type::eof(); 157 const bool __testin = this->_M_mode & ios_base::in; 158 if (__testin) 159 { 160 // Update egptr() to match the actual string end. 161 _M_update_egptr(); 162 163 if (this->gptr() < this->egptr()) 164 __ret = traits_type::to_int_type(*this->gptr()); 165 } 166 return __ret; 167 } 168 169 template <class _CharT, class _Traits, class _Alloc> 170 typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type 171 basic_stringbuf<_CharT, _Traits, _Alloc>:: 172 seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __mode) 173 { 174 pos_type __ret = pos_type(off_type(-1)); 175 bool __testin = (ios_base::in & this->_M_mode & __mode) != 0; 176 bool __testout = (ios_base::out & this->_M_mode & __mode) != 0; 177 const bool __testboth = __testin && __testout && __way != ios_base::cur; 178 __testin &= !(__mode & ios_base::out); 179 __testout &= !(__mode & ios_base::in); 180 181 // _GLIBCXX_RESOLVE_LIB_DEFECTS 182 // 453. basic_stringbuf::seekoff need not always fail for an empty stream. 183 const char_type* __beg = __testin ? this->eback() : this->pbase(); 184 if ((__beg || !__off) && (__testin || __testout || __testboth)) 185 { 186 _M_update_egptr(); 187 188 off_type __newoffi = __off; 189 off_type __newoffo = __newoffi; 190 if (__way == ios_base::cur) 191 { 192 __newoffi += this->gptr() - __beg; 193 __newoffo += this->pptr() - __beg; 194 } 195 else if (__way == ios_base::end) 196 __newoffo = __newoffi += this->egptr() - __beg; 197 198 if ((__testin || __testboth) 199 && __newoffi >= 0 200 && this->egptr() - __beg >= __newoffi) 201 { 202 this->setg(this->eback(), this->eback() + __newoffi, 203 this->egptr()); 204 __ret = pos_type(__newoffi); 205 } 206 if ((__testout || __testboth) 207 && __newoffo >= 0 208 && this->egptr() - __beg >= __newoffo) 209 { 210 _M_pbump(this->pbase(), this->epptr(), __newoffo); 211 __ret = pos_type(__newoffo); 212 } 213 } 214 return __ret; 215 } 216 217 template <class _CharT, class _Traits, class _Alloc> 218 typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type 219 basic_stringbuf<_CharT, _Traits, _Alloc>:: 220 seekpos(pos_type __sp, ios_base::openmode __mode) 221 { 222 pos_type __ret = pos_type(off_type(-1)); 223 const bool __testin = (ios_base::in & this->_M_mode & __mode) != 0; 224 const bool __testout = (ios_base::out & this->_M_mode & __mode) != 0; 225 226 const char_type* __beg = __testin ? this->eback() : this->pbase(); 227 if ((__beg || !off_type(__sp)) && (__testin || __testout)) 228 { 229 _M_update_egptr(); 230 231 const off_type __pos(__sp); 232 const bool __testpos = (0 <= __pos 233 && __pos <= this->egptr() - __beg); 234 if (__testpos) 235 { 236 if (__testin) 237 this->setg(this->eback(), this->eback() + __pos, 238 this->egptr()); 239 if (__testout) 240 _M_pbump(this->pbase(), this->epptr(), __pos); 241 __ret = __sp; 242 } 243 } 244 return __ret; 245 } 246 247 template <class _CharT, class _Traits, class _Alloc> 248 void 249 basic_stringbuf<_CharT, _Traits, _Alloc>:: 250 _M_sync(char_type* __base, __size_type __i, __size_type __o) 251 { 252 const bool __testin = _M_mode & ios_base::in; 253 const bool __testout = _M_mode & ios_base::out; 254 char_type* __endg = __base + _M_string.size(); 255 char_type* __endp = __base + _M_string.capacity(); 256 257 if (__base != _M_string.data()) 258 { 259 // setbuf: __i == size of buffer area (_M_string.size() == 0). 260 __endg += __i; 261 __i = 0; 262 __endp = __endg; 263 } 264 265 if (__testin) 266 this->setg(__base, __base + __i, __endg); 267 if (__testout) 268 { 269 _M_pbump(__base, __endp, __o); 270 // egptr() always tracks the string end. When !__testin, 271 // for the correct functioning of the streambuf inlines 272 // the other get area pointers are identical. 273 if (!__testin) 274 this->setg(__endg, __endg, __endg); 275 } 276 } 277 278 template <class _CharT, class _Traits, class _Alloc> 279 void 280 basic_stringbuf<_CharT, _Traits, _Alloc>:: 281 _M_pbump(char_type* __pbeg, char_type* __pend, off_type __off) 282 { 283 this->setp(__pbeg, __pend); 284 while (__off > __gnu_cxx::__numeric_traits<int>::__max) 285 { 286 this->pbump(__gnu_cxx::__numeric_traits<int>::__max); 287 __off -= __gnu_cxx::__numeric_traits<int>::__max; 288 } 289 this->pbump(__off); 290 } 291 292 // Inhibit implicit instantiations for required instantiations, 293 // which are defined via explicit instantiations elsewhere. 294 #if _GLIBCXX_EXTERN_TEMPLATE 295 extern template class basic_stringbuf<char>; 296 extern template class basic_istringstream<char>; 297 extern template class basic_ostringstream<char>; 298 extern template class basic_stringstream<char>; 299 300 #ifdef _GLIBCXX_USE_WCHAR_T 301 extern template class basic_stringbuf<wchar_t>; 302 extern template class basic_istringstream<wchar_t>; 303 extern template class basic_ostringstream<wchar_t>; 304 extern template class basic_stringstream<wchar_t>; 305 #endif 306 #endif 307 308 _GLIBCXX_END_NAMESPACE_VERSION 309 } // namespace std 310 311 #pragma GCC diagnostic pop 312 #endif
