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