1 // Debugging support implementation -*- C++ -*- 2 3 // Copyright (C) 2003-2018 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 debug/functions.h 26 * This file is a GNU debug extension to the Standard C++ Library. 27 */ 28 29 #ifndef _GLIBCXX_DEBUG_FUNCTIONS_H 30 #define _GLIBCXX_DEBUG_FUNCTIONS_H 1 31 32 #include <bits/move.h> // for __addressof 33 #include <bits/stl_function.h> // for less 34 #if __cplusplus >= 201103L 35 # include <type_traits> // for is_lvalue_reference and conditional. 36 #endif 37 38 #include <debug/helper_functions.h> 39 #include <debug/formatter.h> 40 41 namespace __gnu_debug 42 { 43 template<typename _Iterator, typename _Sequence> 44 class _Safe_iterator; 45 46 template<typename _Sequence> 47 struct _Insert_range_from_self_is_safe 48 { enum { __value = 0 }; }; 49 50 template<typename _Sequence> 51 struct _Is_contiguous_sequence : std::__false_type { }; 52 53 // An arbitrary iterator pointer is not singular. 54 inline bool 55 __check_singular_aux(const void*) { return false; } 56 57 // We may have an iterator that derives from _Safe_iterator_base but isn't 58 // a _Safe_iterator. 59 template<typename _Iterator> 60 inline bool 61 __check_singular(const _Iterator& __x) 62 { return __check_singular_aux(std::__addressof(__x)); } 63 64 /** Non-NULL pointers are nonsingular. */ 65 template<typename _Tp> 66 inline bool 67 __check_singular(const _Tp* __ptr) 68 { return __ptr == 0; } 69 70 /** Assume that some arbitrary iterator is dereferenceable, because we 71 can't prove that it isn't. */ 72 template<typename _Iterator> 73 inline bool 74 __check_dereferenceable(const _Iterator&) 75 { return true; } 76 77 /** Non-NULL pointers are dereferenceable. */ 78 template<typename _Tp> 79 inline bool 80 __check_dereferenceable(const _Tp* __ptr) 81 { return __ptr; } 82 83 /* Checks that [first, last) is a valid range, and then returns 84 * __first. This routine is useful when we can't use a separate 85 * assertion statement because, e.g., we are in a constructor. 86 */ 87 template<typename _InputIterator> 88 inline _InputIterator 89 __check_valid_range(const _InputIterator& __first, 90 const _InputIterator& __last 91 __attribute__((__unused__))) 92 { 93 __glibcxx_check_valid_range(__first, __last); 94 return __first; 95 } 96 97 /* Handle the case where __other is a pointer to _Sequence::value_type. */ 98 template<typename _Iterator, typename _Sequence> 99 inline bool 100 __foreign_iterator_aux4(const _Safe_iterator<_Iterator, _Sequence>& __it, 101 const typename _Sequence::value_type* __other) 102 { 103 typedef const typename _Sequence::value_type* _PointerType; 104 typedef std::less<_PointerType> _Less; 105 #if __cplusplus >= 201103L 106 constexpr _Less __l{}; 107 #else 108 const _Less __l = _Less(); 109 #endif 110 const _Sequence* __seq = __it._M_get_sequence(); 111 const _PointerType __begin = std::__addressof(*__seq->_M_base().begin()); 112 const _PointerType __end = std::__addressof(*(__seq->_M_base().end()-1)); 113 114 // Check whether __other points within the contiguous storage. 115 return __l(__other, __begin) || __l(__end, __other); 116 } 117 118 /* Fallback overload for when we can't tell, assume it is valid. */ 119 template<typename _Iterator, typename _Sequence> 120 inline bool 121 __foreign_iterator_aux4(const _Safe_iterator<_Iterator, _Sequence>&, ...) 122 { return true; } 123 124 /* Handle sequences with contiguous storage */ 125 template<typename _Iterator, typename _Sequence, typename _InputIterator> 126 inline bool 127 __foreign_iterator_aux3(const _Safe_iterator<_Iterator, _Sequence>& __it, 128 const _InputIterator& __other, 129 const _InputIterator& __other_end, 130 std::__true_type) 131 { 132 if (__other == __other_end) 133 return true; // inserting nothing is safe even if not foreign iters 134 if (__it._M_get_sequence()->begin() == __it._M_get_sequence()->end()) 135 return true; // can't be self-inserting if self is empty 136 return __foreign_iterator_aux4(__it, std::__addressof(*__other)); 137 } 138 139 /* Handle non-contiguous containers, assume it is valid. */ 140 template<typename _Iterator, typename _Sequence, typename _InputIterator> 141 inline bool 142 __foreign_iterator_aux3(const _Safe_iterator<_Iterator, _Sequence>&, 143 const _InputIterator&, const _InputIterator&, 144 std::__false_type) 145 { return true; } 146 147 /** Handle debug iterators from the same type of container. */ 148 template<typename _Iterator, typename _Sequence, typename _OtherIterator> 149 inline bool 150 __foreign_iterator_aux2(const _Safe_iterator<_Iterator, _Sequence>& __it, 151 const _Safe_iterator<_OtherIterator, _Sequence>& __other, 152 const _Safe_iterator<_OtherIterator, _Sequence>&) 153 { return __it._M_get_sequence() != __other._M_get_sequence(); } 154 155 /** Handle debug iterators from different types of container. */ 156 template<typename _Iterator, typename _Sequence, typename _OtherIterator, 157 typename _OtherSequence> 158 inline bool 159 __foreign_iterator_aux2(const _Safe_iterator<_Iterator, _Sequence>& __it, 160 const _Safe_iterator<_OtherIterator, _OtherSequence>&, 161 const _Safe_iterator<_OtherIterator, _OtherSequence>&) 162 { return true; } 163 164 /* Handle non-debug iterators. */ 165 template<typename _Iterator, typename _Sequence, typename _InputIterator> 166 inline bool 167 __foreign_iterator_aux2(const _Safe_iterator<_Iterator, _Sequence>& __it, 168 const _InputIterator& __other, 169 const _InputIterator& __other_end) 170 { 171 #if __cplusplus < 201103L 172 typedef _Is_contiguous_sequence<_Sequence> __tag; 173 #else 174 using __lvalref = std::is_lvalue_reference< 175 typename std::iterator_traits<_InputIterator>::reference>; 176 using __contiguous = _Is_contiguous_sequence<_Sequence>; 177 using __tag = typename std::conditional<__lvalref::value, __contiguous, 178 std::__false_type>::type; 179 #endif 180 return __foreign_iterator_aux3(__it, __other, __other_end, __tag()); 181 } 182 183 /* Handle the case where we aren't really inserting a range after all */ 184 template<typename _Iterator, typename _Sequence, typename _Integral> 185 inline bool 186 __foreign_iterator_aux(const _Safe_iterator<_Iterator, _Sequence>&, 187 _Integral, _Integral, 188 std::__true_type) 189 { return true; } 190 191 /* Handle all iterators. */ 192 template<typename _Iterator, typename _Sequence, 193 typename _InputIterator> 194 inline bool 195 __foreign_iterator_aux(const _Safe_iterator<_Iterator, _Sequence>& __it, 196 _InputIterator __other, _InputIterator __other_end, 197 std::__false_type) 198 { 199 return _Insert_range_from_self_is_safe<_Sequence>::__value 200 || __foreign_iterator_aux2(__it, std::__miter_base(__other), 201 std::__miter_base(__other_end)); 202 } 203 204 template<typename _Iterator, typename _Sequence, 205 typename _InputIterator> 206 inline bool 207 __foreign_iterator(const _Safe_iterator<_Iterator, _Sequence>& __it, 208 _InputIterator __other, _InputIterator __other_end) 209 { 210 typedef typename std::__is_integer<_InputIterator>::__type _Integral; 211 return __foreign_iterator_aux(__it, __other, __other_end, _Integral()); 212 } 213 214 /** Checks that __s is non-NULL or __n == 0, and then returns __s. */ 215 template<typename _CharT, typename _Integer> 216 inline const _CharT* 217 __check_string(const _CharT* __s, 218 const _Integer& __n __attribute__((__unused__))) 219 { 220 #ifdef _GLIBCXX_DEBUG_PEDANTIC 221 __glibcxx_assert(__s != 0 || __n == 0); 222 #endif 223 return __s; 224 } 225 226 /** Checks that __s is non-NULL and then returns __s. */ 227 template<typename _CharT> 228 inline const _CharT* 229 __check_string(const _CharT* __s) 230 { 231 #ifdef _GLIBCXX_DEBUG_PEDANTIC 232 __glibcxx_assert(__s != 0); 233 #endif 234 return __s; 235 } 236 237 // Can't check if an input iterator sequence is sorted, because we 238 // can't step through the sequence. 239 template<typename _InputIterator> 240 inline bool 241 __check_sorted_aux(const _InputIterator&, const _InputIterator&, 242 std::input_iterator_tag) 243 { return true; } 244 245 // Can verify if a forward iterator sequence is in fact sorted using 246 // std::__is_sorted 247 template<typename _ForwardIterator> 248 inline bool 249 __check_sorted_aux(_ForwardIterator __first, _ForwardIterator __last, 250 std::forward_iterator_tag) 251 { 252 if (__first == __last) 253 return true; 254 255 _ForwardIterator __next = __first; 256 for (++__next; __next != __last; __first = __next, (void)++__next) 257 if (*__next < *__first) 258 return false; 259 260 return true; 261 } 262 263 // Can't check if an input iterator sequence is sorted, because we can't step 264 // through the sequence. 265 template<typename _InputIterator, typename _Predicate> 266 inline bool 267 __check_sorted_aux(const _InputIterator&, const _InputIterator&, 268 _Predicate, std::input_iterator_tag) 269 { return true; } 270 271 // Can verify if a forward iterator sequence is in fact sorted using 272 // std::__is_sorted 273 template<typename _ForwardIterator, typename _Predicate> 274 inline bool 275 __check_sorted_aux(_ForwardIterator __first, _ForwardIterator __last, 276 _Predicate __pred, std::forward_iterator_tag) 277 { 278 if (__first == __last) 279 return true; 280 281 _ForwardIterator __next = __first; 282 for (++__next; __next != __last; __first = __next, (void)++__next) 283 if (__pred(*__next, *__first)) 284 return false; 285 286 return true; 287 } 288 289 // Determine if a sequence is sorted. 290 template<typename _InputIterator> 291 inline bool 292 __check_sorted(const _InputIterator& __first, const _InputIterator& __last) 293 { 294 // Verify that the < operator for elements in the sequence is a 295 // StrictWeakOrdering by checking that it is irreflexive. 296 __glibcxx_assert(__first == __last || !(*__first < *__first)); 297 298 return __check_sorted_aux(__first, __last, 299 std::__iterator_category(__first)); 300 } 301 302 template<typename _InputIterator, typename _Predicate> 303 inline bool 304 __check_sorted(const _InputIterator& __first, const _InputIterator& __last, 305 _Predicate __pred) 306 { 307 // Verify that the predicate is StrictWeakOrdering by checking that it 308 // is irreflexive. 309 __glibcxx_assert(__first == __last || !__pred(*__first, *__first)); 310 311 return __check_sorted_aux(__first, __last, __pred, 312 std::__iterator_category(__first)); 313 } 314 315 template<typename _InputIterator> 316 inline bool 317 __check_sorted_set_aux(const _InputIterator& __first, 318 const _InputIterator& __last, 319 std::__true_type) 320 { return __check_sorted(__first, __last); } 321 322 template<typename _InputIterator> 323 inline bool 324 __check_sorted_set_aux(const _InputIterator&, 325 const _InputIterator&, 326 std::__false_type) 327 { return true; } 328 329 template<typename _InputIterator, typename _Predicate> 330 inline bool 331 __check_sorted_set_aux(const _InputIterator& __first, 332 const _InputIterator& __last, 333 _Predicate __pred, std::__true_type) 334 { return __check_sorted(__first, __last, __pred); } 335 336 template<typename _InputIterator, typename _Predicate> 337 inline bool 338 __check_sorted_set_aux(const _InputIterator&, 339 const _InputIterator&, _Predicate, 340 std::__false_type) 341 { return true; } 342 343 // ... special variant used in std::merge, std::includes, std::set_*. 344 template<typename _InputIterator1, typename _InputIterator2> 345 inline bool 346 __check_sorted_set(const _InputIterator1& __first, 347 const _InputIterator1& __last, 348 const _InputIterator2&) 349 { 350 typedef typename std::iterator_traits<_InputIterator1>::value_type 351 _ValueType1; 352 typedef typename std::iterator_traits<_InputIterator2>::value_type 353 _ValueType2; 354 355 typedef typename std::__are_same<_ValueType1, _ValueType2>::__type 356 _SameType; 357 return __check_sorted_set_aux(__first, __last, _SameType()); 358 } 359 360 template<typename _InputIterator1, typename _InputIterator2, 361 typename _Predicate> 362 inline bool 363 __check_sorted_set(const _InputIterator1& __first, 364 const _InputIterator1& __last, 365 const _InputIterator2&, _Predicate __pred) 366 { 367 typedef typename std::iterator_traits<_InputIterator1>::value_type 368 _ValueType1; 369 typedef typename std::iterator_traits<_InputIterator2>::value_type 370 _ValueType2; 371 372 typedef typename std::__are_same<_ValueType1, _ValueType2>::__type 373 _SameType; 374 return __check_sorted_set_aux(__first, __last, __pred, _SameType()); 375 } 376 377 // _GLIBCXX_RESOLVE_LIB_DEFECTS 378 // 270. Binary search requirements overly strict 379 // Determine if a sequence is partitioned w.r.t. this element. 380 template<typename _ForwardIterator, typename _Tp> 381 inline bool 382 __check_partitioned_lower(_ForwardIterator __first, 383 _ForwardIterator __last, const _Tp& __value) 384 { 385 while (__first != __last && *__first < __value) 386 ++__first; 387 if (__first != __last) 388 { 389 ++__first; 390 while (__first != __last && !(*__first < __value)) 391 ++__first; 392 } 393 return __first == __last; 394 } 395 396 template<typename _ForwardIterator, typename _Tp> 397 inline bool 398 __check_partitioned_upper(_ForwardIterator __first, 399 _ForwardIterator __last, const _Tp& __value) 400 { 401 while (__first != __last && !(__value < *__first)) 402 ++__first; 403 if (__first != __last) 404 { 405 ++__first; 406 while (__first != __last && __value < *__first) 407 ++__first; 408 } 409 return __first == __last; 410 } 411 412 // Determine if a sequence is partitioned w.r.t. this element. 413 template<typename _ForwardIterator, typename _Tp, typename _Pred> 414 inline bool 415 __check_partitioned_lower(_ForwardIterator __first, 416 _ForwardIterator __last, const _Tp& __value, 417 _Pred __pred) 418 { 419 while (__first != __last && bool(__pred(*__first, __value))) 420 ++__first; 421 if (__first != __last) 422 { 423 ++__first; 424 while (__first != __last && !bool(__pred(*__first, __value))) 425 ++__first; 426 } 427 return __first == __last; 428 } 429 430 template<typename _ForwardIterator, typename _Tp, typename _Pred> 431 inline bool 432 __check_partitioned_upper(_ForwardIterator __first, 433 _ForwardIterator __last, const _Tp& __value, 434 _Pred __pred) 435 { 436 while (__first != __last && !bool(__pred(__value, *__first))) 437 ++__first; 438 if (__first != __last) 439 { 440 ++__first; 441 while (__first != __last && bool(__pred(__value, *__first))) 442 ++__first; 443 } 444 return __first == __last; 445 } 446 447 #if __cplusplus >= 201103L 448 struct _Irreflexive_checker 449 { 450 template<typename _It> 451 static typename std::iterator_traits<_It>::reference 452 __deref(); 453 454 template<typename _It, 455 typename = decltype(__deref<_It>() < __deref<_It>())> 456 static bool 457 _S_is_valid(_It __it) 458 { return !(*__it < *__it); } 459 460 // Fallback method if operator doesn't exist. 461 template<typename... _Args> 462 static bool 463 _S_is_valid(_Args...) 464 { return true; } 465 466 template<typename _It, typename _Pred, typename 467 = decltype(std::declval<_Pred>()(__deref<_It>(), __deref<_It>()))> 468 static bool 469 _S_is_valid_pred(_It __it, _Pred __pred) 470 { return !__pred(*__it, *__it); } 471 472 // Fallback method if predicate can't be invoked. 473 template<typename... _Args> 474 static bool 475 _S_is_valid_pred(_Args...) 476 { return true; } 477 }; 478 479 template<typename _Iterator> 480 inline bool 481 __is_irreflexive(_Iterator __it) 482 { return _Irreflexive_checker::_S_is_valid(__it); } 483 484 template<typename _Iterator, typename _Pred> 485 inline bool 486 __is_irreflexive_pred(_Iterator __it, _Pred __pred) 487 { return _Irreflexive_checker::_S_is_valid_pred(__it, __pred); } 488 #endif 489 490 } // namespace __gnu_debug 491 492 #endif 493