1 // Streambuf iterators 2 3 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 4 // 2006, 2007, 2009 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 streambuf_iterator.h 28 * This is an internal header file, included by other library headers. 29 * You should not attempt to use it directly. 30 */ 31 32 #ifndef _STREAMBUF_ITERATOR_H 33 #define _STREAMBUF_ITERATOR_H 1 34 35 #pragma GCC system_header 36 37 #include <streambuf> 38 #include <debug/debug.h> 39 40 _GLIBCXX_BEGIN_NAMESPACE(std) 41 42 // 24.5.3 Template class istreambuf_iterator 43 /// Provides input iterator semantics for streambufs. 44 template<typename _CharT, typename _Traits> 45 class istreambuf_iterator 46 : public iterator<input_iterator_tag, _CharT, typename _Traits::off_type, 47 _CharT*, _CharT&> 48 { 49 public: 50 // Types: 51 //@{ 52 /// Public typedefs 53 typedef _CharT char_type; 54 typedef _Traits traits_type; 55 typedef typename _Traits::int_type int_type; 56 typedef basic_streambuf<_CharT, _Traits> streambuf_type; 57 typedef basic_istream<_CharT, _Traits> istream_type; 58 //@} 59 60 template<typename _CharT2> 61 friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value, 62 ostreambuf_iterator<_CharT2> >::__type 63 copy(istreambuf_iterator<_CharT2>, istreambuf_iterator<_CharT2>, 64 ostreambuf_iterator<_CharT2>); 65 66 template<bool _IsMove, typename _CharT2> 67 friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value, 68 _CharT2*>::__type 69 __copy_move_a2(istreambuf_iterator<_CharT2>, 70 istreambuf_iterator<_CharT2>, _CharT2*); 71 72 template<typename _CharT2> 73 friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value, 74 istreambuf_iterator<_CharT2> >::__type 75 find(istreambuf_iterator<_CharT2>, istreambuf_iterator<_CharT2>, 76 const _CharT2&); 77 78 private: 79 // 24.5.3 istreambuf_iterator 80 // p 1 81 // If the end of stream is reached (streambuf_type::sgetc() 82 // returns traits_type::eof()), the iterator becomes equal to 83 // the "end of stream" iterator value. 84 // NB: This implementation assumes the "end of stream" value 85 // is EOF, or -1. 86 mutable streambuf_type* _M_sbuf; 87 mutable int_type _M_c; 88 89 public: 90 /// Construct end of input stream iterator. 91 istreambuf_iterator() throw() 92 : _M_sbuf(0), _M_c(traits_type::eof()) { } 93 94 /// Construct start of input stream iterator. 95 istreambuf_iterator(istream_type& __s) throw() 96 : _M_sbuf(__s.rdbuf()), _M_c(traits_type::eof()) { } 97 98 /// Construct start of streambuf iterator. 99 istreambuf_iterator(streambuf_type* __s) throw() 100 : _M_sbuf(__s), _M_c(traits_type::eof()) { } 101 102 /// Return the current character pointed to by iterator. This returns 103 /// streambuf.sgetc(). It cannot be assigned. NB: The result of 104 /// operator*() on an end of stream is undefined. 105 char_type 106 operator*() const 107 { 108 #ifdef _GLIBCXX_DEBUG_PEDANTIC 109 // Dereferencing a past-the-end istreambuf_iterator is a 110 // libstdc++ extension 111 __glibcxx_requires_cond(!_M_at_eof(), 112 _M_message(__gnu_debug::__msg_deref_istreambuf) 113 ._M_iterator(*this)); 114 #endif 115 return traits_type::to_char_type(_M_get()); 116 } 117 118 /// Advance the iterator. Calls streambuf.sbumpc(). 119 istreambuf_iterator& 120 operator++() 121 { 122 __glibcxx_requires_cond(!_M_at_eof(), 123 _M_message(__gnu_debug::__msg_inc_istreambuf) 124 ._M_iterator(*this)); 125 if (_M_sbuf) 126 { 127 _M_sbuf->sbumpc(); 128 _M_c = traits_type::eof(); 129 } 130 return *this; 131 } 132 133 /// Advance the iterator. Calls streambuf.sbumpc(). 134 istreambuf_iterator 135 operator++(int) 136 { 137 __glibcxx_requires_cond(!_M_at_eof(), 138 _M_message(__gnu_debug::__msg_inc_istreambuf) 139 ._M_iterator(*this)); 140 141 istreambuf_iterator __old = *this; 142 if (_M_sbuf) 143 { 144 __old._M_c = _M_sbuf->sbumpc(); 145 _M_c = traits_type::eof(); 146 } 147 return __old; 148 } 149 150 // _GLIBCXX_RESOLVE_LIB_DEFECTS 151 // 110 istreambuf_iterator::equal not const 152 // NB: there is also number 111 (NAD, Future) pending on this function. 153 /// Return true both iterators are end or both are not end. 154 bool 155 equal(const istreambuf_iterator& __b) const 156 { return _M_at_eof() == __b._M_at_eof(); } 157 158 private: 159 int_type 160 _M_get() const 161 { 162 const int_type __eof = traits_type::eof(); 163 int_type __ret = __eof; 164 if (_M_sbuf) 165 { 166 if (!traits_type::eq_int_type(_M_c, __eof)) 167 __ret = _M_c; 168 else if (!traits_type::eq_int_type((__ret = _M_sbuf->sgetc()), 169 __eof)) 170 _M_c = __ret; 171 else 172 _M_sbuf = 0; 173 } 174 return __ret; 175 } 176 177 bool 178 _M_at_eof() const 179 { 180 const int_type __eof = traits_type::eof(); 181 return traits_type::eq_int_type(_M_get(), __eof); 182 } 183 }; 184 185 template<typename _CharT, typename _Traits> 186 inline bool 187 operator==(const istreambuf_iterator<_CharT, _Traits>& __a, 188 const istreambuf_iterator<_CharT, _Traits>& __b) 189 { return __a.equal(__b); } 190 191 template<typename _CharT, typename _Traits> 192 inline bool 193 operator!=(const istreambuf_iterator<_CharT, _Traits>& __a, 194 const istreambuf_iterator<_CharT, _Traits>& __b) 195 { return !__a.equal(__b); } 196 197 /// Provides output iterator semantics for streambufs. 198 template<typename _CharT, typename _Traits> 199 class ostreambuf_iterator 200 : public iterator<output_iterator_tag, void, void, void, void> 201 { 202 public: 203 // Types: 204 //@{ 205 /// Public typedefs 206 typedef _CharT char_type; 207 typedef _Traits traits_type; 208 typedef basic_streambuf<_CharT, _Traits> streambuf_type; 209 typedef basic_ostream<_CharT, _Traits> ostream_type; 210 //@} 211 212 template<typename _CharT2> 213 friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value, 214 ostreambuf_iterator<_CharT2> >::__type 215 copy(istreambuf_iterator<_CharT2>, istreambuf_iterator<_CharT2>, 216 ostreambuf_iterator<_CharT2>); 217 218 private: 219 streambuf_type* _M_sbuf; 220 bool _M_failed; 221 222 public: 223 /// Construct output iterator from ostream. 224 ostreambuf_iterator(ostream_type& __s) throw () 225 : _M_sbuf(__s.rdbuf()), _M_failed(!_M_sbuf) { } 226 227 /// Construct output iterator from streambuf. 228 ostreambuf_iterator(streambuf_type* __s) throw () 229 : _M_sbuf(__s), _M_failed(!_M_sbuf) { } 230 231 /// Write character to streambuf. Calls streambuf.sputc(). 232 ostreambuf_iterator& 233 operator=(_CharT __c) 234 { 235 if (!_M_failed && 236 _Traits::eq_int_type(_M_sbuf->sputc(__c), _Traits::eof())) 237 _M_failed = true; 238 return *this; 239 } 240 241 /// Return *this. 242 ostreambuf_iterator& 243 operator*() 244 { return *this; } 245 246 /// Return *this. 247 ostreambuf_iterator& 248 operator++(int) 249 { return *this; } 250 251 /// Return *this. 252 ostreambuf_iterator& 253 operator++() 254 { return *this; } 255 256 /// Return true if previous operator=() failed. 257 bool 258 failed() const throw() 259 { return _M_failed; } 260 261 ostreambuf_iterator& 262 _M_put(const _CharT* __ws, streamsize __len) 263 { 264 if (__builtin_expect(!_M_failed, true) 265 && __builtin_expect(this->_M_sbuf->sputn(__ws, __len) != __len, 266 false)) 267 _M_failed = true; 268 return *this; 269 } 270 }; 271 272 // Overloads for streambuf iterators. 273 template<typename _CharT> 274 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, 275 ostreambuf_iterator<_CharT> >::__type 276 copy(istreambuf_iterator<_CharT> __first, 277 istreambuf_iterator<_CharT> __last, 278 ostreambuf_iterator<_CharT> __result) 279 { 280 if (__first._M_sbuf && !__last._M_sbuf && !__result._M_failed) 281 { 282 bool __ineof; 283 __copy_streambufs_eof(__first._M_sbuf, __result._M_sbuf, __ineof); 284 if (!__ineof) 285 __result._M_failed = true; 286 } 287 return __result; 288 } 289 290 template<bool _IsMove, typename _CharT> 291 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, 292 ostreambuf_iterator<_CharT> >::__type 293 __copy_move_a2(_CharT* __first, _CharT* __last, 294 ostreambuf_iterator<_CharT> __result) 295 { 296 const streamsize __num = __last - __first; 297 if (__num > 0) 298 __result._M_put(__first, __num); 299 return __result; 300 } 301 302 template<bool _IsMove, typename _CharT> 303 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, 304 ostreambuf_iterator<_CharT> >::__type 305 __copy_move_a2(const _CharT* __first, const _CharT* __last, 306 ostreambuf_iterator<_CharT> __result) 307 { 308 const streamsize __num = __last - __first; 309 if (__num > 0) 310 __result._M_put(__first, __num); 311 return __result; 312 } 313 314 template<bool _IsMove, typename _CharT> 315 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, 316 _CharT*>::__type 317 __copy_move_a2(istreambuf_iterator<_CharT> __first, 318 istreambuf_iterator<_CharT> __last, _CharT* __result) 319 { 320 typedef istreambuf_iterator<_CharT> __is_iterator_type; 321 typedef typename __is_iterator_type::traits_type traits_type; 322 typedef typename __is_iterator_type::streambuf_type streambuf_type; 323 typedef typename traits_type::int_type int_type; 324 325 if (__first._M_sbuf && !__last._M_sbuf) 326 { 327 streambuf_type* __sb = __first._M_sbuf; 328 int_type __c = __sb->sgetc(); 329 while (!traits_type::eq_int_type(__c, traits_type::eof())) 330 { 331 const streamsize __n = __sb->egptr() - __sb->gptr(); 332 if (__n > 1) 333 { 334 traits_type::copy(__result, __sb->gptr(), __n); 335 __sb->gbump(__n); 336 __result += __n; 337 __c = __sb->underflow(); 338 } 339 else 340 { 341 *__result++ = traits_type::to_char_type(__c); 342 __c = __sb->snextc(); 343 } 344 } 345 } 346 return __result; 347 } 348 349 template<typename _CharT> 350 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, 351 istreambuf_iterator<_CharT> >::__type 352 find(istreambuf_iterator<_CharT> __first, 353 istreambuf_iterator<_CharT> __last, const _CharT& __val) 354 { 355 typedef istreambuf_iterator<_CharT> __is_iterator_type; 356 typedef typename __is_iterator_type::traits_type traits_type; 357 typedef typename __is_iterator_type::streambuf_type streambuf_type; 358 typedef typename traits_type::int_type int_type; 359 360 if (__first._M_sbuf && !__last._M_sbuf) 361 { 362 const int_type __ival = traits_type::to_int_type(__val); 363 streambuf_type* __sb = __first._M_sbuf; 364 int_type __c = __sb->sgetc(); 365 while (!traits_type::eq_int_type(__c, traits_type::eof()) 366 && !traits_type::eq_int_type(__c, __ival)) 367 { 368 streamsize __n = __sb->egptr() - __sb->gptr(); 369 if (__n > 1) 370 { 371 const _CharT* __p = traits_type::find(__sb->gptr(), 372 __n, __val); 373 if (__p) 374 __n = __p - __sb->gptr(); 375 __sb->gbump(__n); 376 __c = __sb->sgetc(); 377 } 378 else 379 __c = __sb->snextc(); 380 } 381 382 if (!traits_type::eq_int_type(__c, traits_type::eof())) 383 __first._M_c = __c; 384 else 385 __first._M_sbuf = 0; 386 } 387 return __first; 388 } 389 390 _GLIBCXX_END_NAMESPACE 391 392 #endif 393