1 // Streambuf iterators 2 3 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 4 // Free Software Foundation, Inc. 5 // 6 // This file is part of the GNU ISO C++ Library. This library is free 7 // software; you can redistribute it and/or modify it under the 8 // terms of the GNU General Public License as published by the 9 // Free Software Foundation; either version 2, or (at your option) 10 // any later version. 11 12 // This library is distributed in the hope that it will be useful, 13 // but WITHOUT ANY WARRANTY; without even the implied warranty of 14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 // GNU General Public License for more details. 16 17 // You should have received a copy of the GNU General Public License along 18 // with this library; see the file COPYING. If not, write to the Free 19 // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, 20 // USA. 21 22 // As a special exception, you may use this file as part of a free software 23 // library without restriction. Specifically, if other files instantiate 24 // templates or use macros or inline functions from this file, or you compile 25 // this file and link it with other files to produce an executable, this 26 // file does not by itself cause the resulting executable to be covered by 27 // the GNU General Public License. This exception does not however 28 // invalidate any other reasons why the executable file might be covered by 29 // the GNU General Public License. 30 31 /** @file streambuf_iterator.h 32 * This is an internal header file, included by other library headers. 33 * You should not attempt to use it directly. 34 */ 35 36 #ifndef _STREAMBUF_ITERATOR_H 37 #define _STREAMBUF_ITERATOR_H 1 38 39 #pragma GCC system_header 40 41 #include <streambuf> 42 #include <debug/debug.h> 43 44 _GLIBCXX_BEGIN_NAMESPACE(std) 45 46 // 24.5.3 Template class istreambuf_iterator 47 /// Provides input iterator semantics for streambufs. 48 template<typename _CharT, typename _Traits> 49 class istreambuf_iterator 50 : public iterator<input_iterator_tag, _CharT, typename _Traits::off_type, 51 _CharT*, _CharT&> 52 { 53 public: 54 // Types: 55 //@{ 56 /// Public typedefs 57 typedef _CharT char_type; 58 typedef _Traits traits_type; 59 typedef typename _Traits::int_type int_type; 60 typedef basic_streambuf<_CharT, _Traits> streambuf_type; 61 typedef basic_istream<_CharT, _Traits> istream_type; 62 //@} 63 64 template<typename _CharT2> 65 friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value, 66 ostreambuf_iterator<_CharT2> >::__type 67 copy(istreambuf_iterator<_CharT2>, istreambuf_iterator<_CharT2>, 68 ostreambuf_iterator<_CharT2>); 69 70 template<typename _CharT2> 71 friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value, 72 _CharT2*>::__type 73 __copy_aux(istreambuf_iterator<_CharT2>, istreambuf_iterator<_CharT2>, 74 _CharT2*); 75 76 template<typename _CharT2> 77 friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value, 78 istreambuf_iterator<_CharT2> >::__type 79 find(istreambuf_iterator<_CharT2>, istreambuf_iterator<_CharT2>, 80 const _CharT2&); 81 82 private: 83 // 24.5.3 istreambuf_iterator 84 // p 1 85 // If the end of stream is reached (streambuf_type::sgetc() 86 // returns traits_type::eof()), the iterator becomes equal to 87 // the "end of stream" iterator value. 88 // NB: This implementation assumes the "end of stream" value 89 // is EOF, or -1. 90 mutable streambuf_type* _M_sbuf; 91 mutable int_type _M_c; 92 93 public: 94 /// Construct end of input stream iterator. 95 istreambuf_iterator() throw() 96 : _M_sbuf(0), _M_c(traits_type::eof()) { } 97 98 /// Construct start of input stream iterator. 99 istreambuf_iterator(istream_type& __s) throw() 100 : _M_sbuf(__s.rdbuf()), _M_c(traits_type::eof()) { } 101 102 /// Construct start of streambuf iterator. 103 istreambuf_iterator(streambuf_type* __s) throw() 104 : _M_sbuf(__s), _M_c(traits_type::eof()) { } 105 106 /// Return the current character pointed to by iterator. This returns 107 /// streambuf.sgetc(). It cannot be assigned. NB: The result of 108 /// operator*() on an end of stream is undefined. 109 char_type 110 operator*() const 111 { 112 #ifdef _GLIBCXX_DEBUG_PEDANTIC 113 // Dereferencing a past-the-end istreambuf_iterator is a 114 // libstdc++ extension 115 __glibcxx_requires_cond(!_M_at_eof(), 116 _M_message(__gnu_debug::__msg_deref_istreambuf) 117 ._M_iterator(*this)); 118 #endif 119 return traits_type::to_char_type(_M_get()); 120 } 121 122 /// Advance the iterator. Calls streambuf.sbumpc(). 123 istreambuf_iterator& 124 operator++() 125 { 126 __glibcxx_requires_cond(!_M_at_eof(), 127 _M_message(__gnu_debug::__msg_inc_istreambuf) 128 ._M_iterator(*this)); 129 if (_M_sbuf) 130 { 131 _M_sbuf->sbumpc(); 132 _M_c = traits_type::eof(); 133 } 134 return *this; 135 } 136 137 /// Advance the iterator. Calls streambuf.sbumpc(). 138 istreambuf_iterator 139 operator++(int) 140 { 141 __glibcxx_requires_cond(!_M_at_eof(), 142 _M_message(__gnu_debug::__msg_inc_istreambuf) 143 ._M_iterator(*this)); 144 145 istreambuf_iterator __old = *this; 146 if (_M_sbuf) 147 { 148 __old._M_c = _M_sbuf->sbumpc(); 149 _M_c = traits_type::eof(); 150 } 151 return __old; 152 } 153 154 // _GLIBCXX_RESOLVE_LIB_DEFECTS 155 // 110 istreambuf_iterator::equal not const 156 // NB: there is also number 111 (NAD, Future) pending on this function. 157 /// Return true both iterators are end or both are not end. 158 bool 159 equal(const istreambuf_iterator& __b) const 160 { 161 const bool __thiseof = _M_at_eof(); 162 const bool __beof = __b._M_at_eof(); 163 return (__thiseof && __beof || (!__thiseof && !__beof)); 164 } 165 166 private: 167 int_type 168 _M_get() const 169 { 170 const int_type __eof = traits_type::eof(); 171 int_type __ret = __eof; 172 if (_M_sbuf) 173 { 174 if (!traits_type::eq_int_type(_M_c, __eof)) 175 __ret = _M_c; 176 else if (!traits_type::eq_int_type((__ret = _M_sbuf->sgetc()), 177 __eof)) 178 _M_c = __ret; 179 else 180 _M_sbuf = 0; 181 } 182 return __ret; 183 } 184 185 bool 186 _M_at_eof() const 187 { 188 const int_type __eof = traits_type::eof(); 189 return traits_type::eq_int_type(_M_get(), __eof); 190 } 191 }; 192 193 template<typename _CharT, typename _Traits> 194 inline bool 195 operator==(const istreambuf_iterator<_CharT, _Traits>& __a, 196 const istreambuf_iterator<_CharT, _Traits>& __b) 197 { return __a.equal(__b); } 198 199 template<typename _CharT, typename _Traits> 200 inline bool 201 operator!=(const istreambuf_iterator<_CharT, _Traits>& __a, 202 const istreambuf_iterator<_CharT, _Traits>& __b) 203 { return !__a.equal(__b); } 204 205 /// Provides output iterator semantics for streambufs. 206 template<typename _CharT, typename _Traits> 207 class ostreambuf_iterator 208 : public iterator<output_iterator_tag, void, void, void, void> 209 { 210 public: 211 // Types: 212 //@{ 213 /// Public typedefs 214 typedef _CharT char_type; 215 typedef _Traits traits_type; 216 typedef basic_streambuf<_CharT, _Traits> streambuf_type; 217 typedef basic_ostream<_CharT, _Traits> ostream_type; 218 //@} 219 220 template<typename _CharT2> 221 friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value, 222 ostreambuf_iterator<_CharT2> >::__type 223 copy(istreambuf_iterator<_CharT2>, istreambuf_iterator<_CharT2>, 224 ostreambuf_iterator<_CharT2>); 225 226 private: 227 streambuf_type* _M_sbuf; 228 bool _M_failed; 229 230 public: 231 /// Construct output iterator from ostream. 232 ostreambuf_iterator(ostream_type& __s) throw () 233 : _M_sbuf(__s.rdbuf()), _M_failed(!_M_sbuf) { } 234 235 /// Construct output iterator from streambuf. 236 ostreambuf_iterator(streambuf_type* __s) throw () 237 : _M_sbuf(__s), _M_failed(!_M_sbuf) { } 238 239 /// Write character to streambuf. Calls streambuf.sputc(). 240 ostreambuf_iterator& 241 operator=(_CharT __c) 242 { 243 if (!_M_failed && 244 _Traits::eq_int_type(_M_sbuf->sputc(__c), _Traits::eof())) 245 _M_failed = true; 246 return *this; 247 } 248 249 /// Return *this. 250 ostreambuf_iterator& 251 operator*() 252 { return *this; } 253 254 /// Return *this. 255 ostreambuf_iterator& 256 operator++(int) 257 { return *this; } 258 259 /// Return *this. 260 ostreambuf_iterator& 261 operator++() 262 { return *this; } 263 264 /// Return true if previous operator=() failed. 265 bool 266 failed() const throw() 267 { return _M_failed; } 268 269 ostreambuf_iterator& 270 _M_put(const _CharT* __ws, streamsize __len) 271 { 272 if (__builtin_expect(!_M_failed, true) 273 && __builtin_expect(this->_M_sbuf->sputn(__ws, __len) != __len, 274 false)) 275 _M_failed = true; 276 return *this; 277 } 278 }; 279 280 // Overloads for streambuf iterators. 281 template<typename _CharT> 282 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, 283 ostreambuf_iterator<_CharT> >::__type 284 copy(istreambuf_iterator<_CharT> __first, 285 istreambuf_iterator<_CharT> __last, 286 ostreambuf_iterator<_CharT> __result) 287 { 288 if (__first._M_sbuf && !__last._M_sbuf && !__result._M_failed) 289 { 290 bool __ineof; 291 __copy_streambufs_eof(__first._M_sbuf, __result._M_sbuf, __ineof); 292 if (!__ineof) 293 __result._M_failed = true; 294 } 295 return __result; 296 } 297 298 template<typename _CharT> 299 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, 300 ostreambuf_iterator<_CharT> >::__type 301 __copy_aux(_CharT* __first, _CharT* __last, 302 ostreambuf_iterator<_CharT> __result) 303 { 304 const streamsize __num = __last - __first; 305 if (__num > 0) 306 __result._M_put(__first, __num); 307 return __result; 308 } 309 310 template<typename _CharT> 311 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, 312 ostreambuf_iterator<_CharT> >::__type 313 __copy_aux(const _CharT* __first, const _CharT* __last, 314 ostreambuf_iterator<_CharT> __result) 315 { 316 const streamsize __num = __last - __first; 317 if (__num > 0) 318 __result._M_put(__first, __num); 319 return __result; 320 } 321 322 template<typename _CharT> 323 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, 324 _CharT*>::__type 325 __copy_aux(istreambuf_iterator<_CharT> __first, 326 istreambuf_iterator<_CharT> __last, _CharT* __result) 327 { 328 typedef istreambuf_iterator<_CharT> __is_iterator_type; 329 typedef typename __is_iterator_type::traits_type traits_type; 330 typedef typename __is_iterator_type::streambuf_type streambuf_type; 331 typedef typename traits_type::int_type int_type; 332 333 if (__first._M_sbuf && !__last._M_sbuf) 334 { 335 streambuf_type* __sb = __first._M_sbuf; 336 int_type __c = __sb->sgetc(); 337 while (!traits_type::eq_int_type(__c, traits_type::eof())) 338 { 339 const streamsize __n = __sb->egptr() - __sb->gptr(); 340 if (__n > 1) 341 { 342 traits_type::copy(__result, __sb->gptr(), __n); 343 __sb->gbump(__n); 344 __result += __n; 345 __c = __sb->underflow(); 346 } 347 else 348 { 349 *__result++ = traits_type::to_char_type(__c); 350 __c = __sb->snextc(); 351 } 352 } 353 } 354 return __result; 355 } 356 357 template<typename _CharT> 358 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, 359 istreambuf_iterator<_CharT> >::__type 360 find(istreambuf_iterator<_CharT> __first, 361 istreambuf_iterator<_CharT> __last, const _CharT& __val) 362 { 363 typedef istreambuf_iterator<_CharT> __is_iterator_type; 364 typedef typename __is_iterator_type::traits_type traits_type; 365 typedef typename __is_iterator_type::streambuf_type streambuf_type; 366 typedef typename traits_type::int_type int_type; 367 368 if (__first._M_sbuf && !__last._M_sbuf) 369 { 370 const int_type __ival = traits_type::to_int_type(__val); 371 streambuf_type* __sb = __first._M_sbuf; 372 int_type __c = __sb->sgetc(); 373 while (!traits_type::eq_int_type(__c, traits_type::eof()) 374 && !traits_type::eq_int_type(__c, __ival)) 375 { 376 streamsize __n = __sb->egptr() - __sb->gptr(); 377 if (__n > 1) 378 { 379 const _CharT* __p = traits_type::find(__sb->gptr(), 380 __n, __val); 381 if (__p) 382 __n = __p - __sb->gptr(); 383 __sb->gbump(__n); 384 __c = __sb->sgetc(); 385 } 386 else 387 __c = __sb->snextc(); 388 } 389 390 if (!traits_type::eq_int_type(__c, traits_type::eof())) 391 __first._M_c = __c; 392 else 393 __first._M_sbuf = 0; 394 } 395 return __first; 396 } 397 398 _GLIBCXX_END_NAMESPACE 399 400 #endif 401