1 // Streambuf iterators 2 3 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 4 // 2006, 2007, 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/streambuf_iterator.h 28 * This is an internal header file, included by other library headers. 29 * Do not attempt to use it directly. @headername{iterator} 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 namespace std _GLIBCXX_VISIBILITY(default) 41 { 42 _GLIBCXX_BEGIN_NAMESPACE_VERSION 43 44 /** 45 * @addtogroup iterators 46 * @{ 47 */ 48 49 // 24.5.3 Template class istreambuf_iterator 50 /// Provides input iterator semantics for streambufs. 51 template<typename _CharT, typename _Traits> 52 class istreambuf_iterator 53 : public iterator<input_iterator_tag, _CharT, typename _Traits::off_type, 54 _CharT*, 55 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 56 // LWG 445. 57 _CharT> 58 #else 59 _CharT&> 60 #endif 61 { 62 public: 63 // Types: 64 //@{ 65 /// Public typedefs 66 typedef _CharT char_type; 67 typedef _Traits traits_type; 68 typedef typename _Traits::int_type int_type; 69 typedef basic_streambuf<_CharT, _Traits> streambuf_type; 70 typedef basic_istream<_CharT, _Traits> istream_type; 71 //@} 72 73 template<typename _CharT2> 74 friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value, 75 ostreambuf_iterator<_CharT2> >::__type 76 copy(istreambuf_iterator<_CharT2>, istreambuf_iterator<_CharT2>, 77 ostreambuf_iterator<_CharT2>); 78 79 template<bool _IsMove, typename _CharT2> 80 friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value, 81 _CharT2*>::__type 82 __copy_move_a2(istreambuf_iterator<_CharT2>, 83 istreambuf_iterator<_CharT2>, _CharT2*); 84 85 template<typename _CharT2> 86 friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value, 87 istreambuf_iterator<_CharT2> >::__type 88 find(istreambuf_iterator<_CharT2>, istreambuf_iterator<_CharT2>, 89 const _CharT2&); 90 91 private: 92 // 24.5.3 istreambuf_iterator 93 // p 1 94 // If the end of stream is reached (streambuf_type::sgetc() 95 // returns traits_type::eof()), the iterator becomes equal to 96 // the "end of stream" iterator value. 97 // NB: This implementation assumes the "end of stream" value 98 // is EOF, or -1. 99 mutable streambuf_type* _M_sbuf; 100 mutable int_type _M_c; 101 102 public: 103 /// Construct end of input stream iterator. 104 _GLIBCXX_CONSTEXPR istreambuf_iterator() _GLIBCXX_USE_NOEXCEPT 105 : _M_sbuf(0), _M_c(traits_type::eof()) { } 106 107 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 108 istreambuf_iterator(const istreambuf_iterator&) noexcept = default; 109 110 ~istreambuf_iterator() = default; 111 #endif 112 113 /// Construct start of input stream iterator. 114 istreambuf_iterator(istream_type& __s) _GLIBCXX_USE_NOEXCEPT 115 : _M_sbuf(__s.rdbuf()), _M_c(traits_type::eof()) { } 116 117 /// Construct start of streambuf iterator. 118 istreambuf_iterator(streambuf_type* __s) _GLIBCXX_USE_NOEXCEPT 119 : _M_sbuf(__s), _M_c(traits_type::eof()) { } 120 121 /// Return the current character pointed to by iterator. This returns 122 /// streambuf.sgetc(). It cannot be assigned. NB: The result of 123 /// operator*() on an end of stream is undefined. 124 char_type 125 operator*() const 126 { 127 #ifdef _GLIBCXX_DEBUG_PEDANTIC 128 // Dereferencing a past-the-end istreambuf_iterator is a 129 // libstdc++ extension 130 __glibcxx_requires_cond(!_M_at_eof(), 131 _M_message(__gnu_debug::__msg_deref_istreambuf) 132 ._M_iterator(*this)); 133 #endif 134 return traits_type::to_char_type(_M_get()); 135 } 136 137 /// Advance the iterator. Calls streambuf.sbumpc(). 138 istreambuf_iterator& 139 operator++() 140 { 141 __glibcxx_requires_cond(!_M_at_eof(), 142 _M_message(__gnu_debug::__msg_inc_istreambuf) 143 ._M_iterator(*this)); 144 if (_M_sbuf) 145 { 146 _M_sbuf->sbumpc(); 147 _M_c = traits_type::eof(); 148 } 149 return *this; 150 } 151 152 /// Advance the iterator. Calls streambuf.sbumpc(). 153 istreambuf_iterator 154 operator++(int) 155 { 156 __glibcxx_requires_cond(!_M_at_eof(), 157 _M_message(__gnu_debug::__msg_inc_istreambuf) 158 ._M_iterator(*this)); 159 160 istreambuf_iterator __old = *this; 161 if (_M_sbuf) 162 { 163 __old._M_c = _M_sbuf->sbumpc(); 164 _M_c = traits_type::eof(); 165 } 166 return __old; 167 } 168 169 // _GLIBCXX_RESOLVE_LIB_DEFECTS 170 // 110 istreambuf_iterator::equal not const 171 // NB: there is also number 111 (NAD, Future) pending on this function. 172 /// Return true both iterators are end or both are not end. 173 bool 174 equal(const istreambuf_iterator& __b) const 175 { return _M_at_eof() == __b._M_at_eof(); } 176 177 private: 178 int_type 179 _M_get() const 180 { 181 const int_type __eof = traits_type::eof(); 182 int_type __ret = __eof; 183 if (_M_sbuf) 184 { 185 if (!traits_type::eq_int_type(_M_c, __eof)) 186 __ret = _M_c; 187 else if (!traits_type::eq_int_type((__ret = _M_sbuf->sgetc()), 188 __eof)) 189 _M_c = __ret; 190 else 191 _M_sbuf = 0; 192 } 193 return __ret; 194 } 195 196 bool 197 _M_at_eof() const 198 { 199 const int_type __eof = traits_type::eof(); 200 return traits_type::eq_int_type(_M_get(), __eof); 201 } 202 }; 203 204 template<typename _CharT, typename _Traits> 205 inline bool 206 operator==(const istreambuf_iterator<_CharT, _Traits>& __a, 207 const istreambuf_iterator<_CharT, _Traits>& __b) 208 { return __a.equal(__b); } 209 210 template<typename _CharT, typename _Traits> 211 inline bool 212 operator!=(const istreambuf_iterator<_CharT, _Traits>& __a, 213 const istreambuf_iterator<_CharT, _Traits>& __b) 214 { return !__a.equal(__b); } 215 216 /// Provides output iterator semantics for streambufs. 217 template<typename _CharT, typename _Traits> 218 class ostreambuf_iterator 219 : public iterator<output_iterator_tag, void, void, void, void> 220 { 221 public: 222 // Types: 223 //@{ 224 /// Public typedefs 225 typedef _CharT char_type; 226 typedef _Traits traits_type; 227 typedef basic_streambuf<_CharT, _Traits> streambuf_type; 228 typedef basic_ostream<_CharT, _Traits> ostream_type; 229 //@} 230 231 template<typename _CharT2> 232 friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value, 233 ostreambuf_iterator<_CharT2> >::__type 234 copy(istreambuf_iterator<_CharT2>, istreambuf_iterator<_CharT2>, 235 ostreambuf_iterator<_CharT2>); 236 237 private: 238 streambuf_type* _M_sbuf; 239 bool _M_failed; 240 241 public: 242 /// Construct output iterator from ostream. 243 ostreambuf_iterator(ostream_type& __s) _GLIBCXX_USE_NOEXCEPT 244 : _M_sbuf(__s.rdbuf()), _M_failed(!_M_sbuf) { } 245 246 /// Construct output iterator from streambuf. 247 ostreambuf_iterator(streambuf_type* __s) _GLIBCXX_USE_NOEXCEPT 248 : _M_sbuf(__s), _M_failed(!_M_sbuf) { } 249 250 /// Write character to streambuf. Calls streambuf.sputc(). 251 ostreambuf_iterator& 252 operator=(_CharT __c) 253 { 254 if (!_M_failed && 255 _Traits::eq_int_type(_M_sbuf->sputc(__c), _Traits::eof())) 256 _M_failed = true; 257 return *this; 258 } 259 260 /// Return *this. 261 ostreambuf_iterator& 262 operator*() 263 { return *this; } 264 265 /// Return *this. 266 ostreambuf_iterator& 267 operator++(int) 268 { return *this; } 269 270 /// Return *this. 271 ostreambuf_iterator& 272 operator++() 273 { return *this; } 274 275 /// Return true if previous operator=() failed. 276 bool 277 failed() const _GLIBCXX_USE_NOEXCEPT 278 { return _M_failed; } 279 280 ostreambuf_iterator& 281 _M_put(const _CharT* __ws, streamsize __len) 282 { 283 if (__builtin_expect(!_M_failed, true) 284 && __builtin_expect(this->_M_sbuf->sputn(__ws, __len) != __len, 285 false)) 286 _M_failed = true; 287 return *this; 288 } 289 }; 290 291 // Overloads for streambuf iterators. 292 template<typename _CharT> 293 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, 294 ostreambuf_iterator<_CharT> >::__type 295 copy(istreambuf_iterator<_CharT> __first, 296 istreambuf_iterator<_CharT> __last, 297 ostreambuf_iterator<_CharT> __result) 298 { 299 if (__first._M_sbuf && !__last._M_sbuf && !__result._M_failed) 300 { 301 bool __ineof; 302 __copy_streambufs_eof(__first._M_sbuf, __result._M_sbuf, __ineof); 303 if (!__ineof) 304 __result._M_failed = true; 305 } 306 return __result; 307 } 308 309 template<bool _IsMove, typename _CharT> 310 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, 311 ostreambuf_iterator<_CharT> >::__type 312 __copy_move_a2(_CharT* __first, _CharT* __last, 313 ostreambuf_iterator<_CharT> __result) 314 { 315 const streamsize __num = __last - __first; 316 if (__num > 0) 317 __result._M_put(__first, __num); 318 return __result; 319 } 320 321 template<bool _IsMove, typename _CharT> 322 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, 323 ostreambuf_iterator<_CharT> >::__type 324 __copy_move_a2(const _CharT* __first, const _CharT* __last, 325 ostreambuf_iterator<_CharT> __result) 326 { 327 const streamsize __num = __last - __first; 328 if (__num > 0) 329 __result._M_put(__first, __num); 330 return __result; 331 } 332 333 template<bool _IsMove, typename _CharT> 334 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, 335 _CharT*>::__type 336 __copy_move_a2(istreambuf_iterator<_CharT> __first, 337 istreambuf_iterator<_CharT> __last, _CharT* __result) 338 { 339 typedef istreambuf_iterator<_CharT> __is_iterator_type; 340 typedef typename __is_iterator_type::traits_type traits_type; 341 typedef typename __is_iterator_type::streambuf_type streambuf_type; 342 typedef typename traits_type::int_type int_type; 343 344 if (__first._M_sbuf && !__last._M_sbuf) 345 { 346 streambuf_type* __sb = __first._M_sbuf; 347 int_type __c = __sb->sgetc(); 348 while (!traits_type::eq_int_type(__c, traits_type::eof())) 349 { 350 const streamsize __n = __sb->egptr() - __sb->gptr(); 351 if (__n > 1) 352 { 353 traits_type::copy(__result, __sb->gptr(), __n); 354 __sb->__safe_gbump(__n); 355 __result += __n; 356 __c = __sb->underflow(); 357 } 358 else 359 { 360 *__result++ = traits_type::to_char_type(__c); 361 __c = __sb->snextc(); 362 } 363 } 364 } 365 return __result; 366 } 367 368 template<typename _CharT> 369 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, 370 istreambuf_iterator<_CharT> >::__type 371 find(istreambuf_iterator<_CharT> __first, 372 istreambuf_iterator<_CharT> __last, const _CharT& __val) 373 { 374 typedef istreambuf_iterator<_CharT> __is_iterator_type; 375 typedef typename __is_iterator_type::traits_type traits_type; 376 typedef typename __is_iterator_type::streambuf_type streambuf_type; 377 typedef typename traits_type::int_type int_type; 378 379 if (__first._M_sbuf && !__last._M_sbuf) 380 { 381 const int_type __ival = traits_type::to_int_type(__val); 382 streambuf_type* __sb = __first._M_sbuf; 383 int_type __c = __sb->sgetc(); 384 while (!traits_type::eq_int_type(__c, traits_type::eof()) 385 && !traits_type::eq_int_type(__c, __ival)) 386 { 387 streamsize __n = __sb->egptr() - __sb->gptr(); 388 if (__n > 1) 389 { 390 const _CharT* __p = traits_type::find(__sb->gptr(), 391 __n, __val); 392 if (__p) 393 __n = __p - __sb->gptr(); 394 __sb->__safe_gbump(__n); 395 __c = __sb->sgetc(); 396 } 397 else 398 __c = __sb->snextc(); 399 } 400 401 if (!traits_type::eq_int_type(__c, traits_type::eof())) 402 __first._M_c = __c; 403 else 404 __first._M_sbuf = 0; 405 } 406 return __first; 407 } 408 409 // @} group iterators 410 411 _GLIBCXX_END_NAMESPACE_VERSION 412 } // namespace 413 414 #endif 415
