Where Online Learning is simpler!

The C and C++ Include Header Files

/usr/include/c++/13/debug/safe_unordered_container.h

$ cat -n /usr/include/c++/13/debug/safe_unordered_container.h

     1	// Safe container implementation  -*- C++ -*-
     2	
     3	// Copyright (C) 2011-2023 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/safe_unordered_container.h
    26	 *  This file is a GNU debug extension to the Standard C++ Library.
    27	 */
    28	
    29	#ifndef _GLIBCXX_DEBUG_SAFE_UNORDERED_CONTAINER_H
    30	#define _GLIBCXX_DEBUG_SAFE_UNORDERED_CONTAINER_H 1
    31	
    32	#include <debug/assertions.h>
    33	#include <debug/macros.h>
    34	#include <debug/functions.h>
    35	#include <debug/safe_unordered_base.h>
    36	
    37	namespace __gnu_debug
    38	{
    39	  /**
    40	   * @brief Base class for constructing a @a safe unordered container type
    41	   * that tracks iterators that reference it.
    42	   *
    43	   * The class template %_Safe_unordered_container simplifies the
    44	   * construction of @a safe unordered containers that track the iterators
    45	   * that reference the container, so that the iterators are notified of
    46	   * changes in the container that may affect their operation, e.g., if
    47	   * the container invalidates its iterators or is destructed. This class
    48	   * template may only be used by deriving from it and passing the name
    49	   * of the derived class as its template parameter via the curiously
    50	   * recurring template pattern. The derived class must have @c
    51	   * iterator and @c const_iterator types that are instantiations of
    52	   * class template _Safe_iterator for this container and @c local_iterator
    53	   * and @c const_local_iterator types that are instantiations of class
    54	   * template _Safe_local_iterator for this container. Iterators will
    55	   * then be tracked automatically.
    56	   */
    57	  template<typename _Container>
    58	    class _Safe_unordered_container : public _Safe_unordered_container_base
    59	    {
    60	    private:
    61	      _Container&
    62	      _M_cont() noexcept
    63	      { return *static_cast<_Container*>(this); }
    64	
    65	    protected:
    66	      void
    67	      _M_invalidate_locals()
    68	      {
    69		auto __local_end = _M_cont()._M_base().cend(0);
    70		this->_M_invalidate_local_if(
    71			[__local_end](__decltype(__local_end) __it)
    72			{ return __it != __local_end; });
    73	      }
    74	
    75	#if __cplusplus > 201402L
    76	      template<typename _ExtractKey, typename _Source>
    77		struct _UContInvalidatePred
    78		{
    79		  template<typename _Iterator>
    80		    bool
    81		    operator()(_Iterator __it) const
    82		    { return _M_source.count(_ExtractKey{}(*__it)) == 0; }
    83	
    84		  const _Source& _M_source;
    85		};
    86	
    87	      template<typename _ExtractKey, typename _Source>
    88		struct _UMContInvalidatePred
    89		{
    90		  template<typename _Iterator>
    91		    bool
    92		    operator()(_Iterator __it) const
    93		    {
    94		      auto __rng =
    95			_M_source._M_base().equal_range(_ExtractKey{}(*__it));
    96		      for (auto __rit = __rng.first;
    97			   __rit != __rng.second; ++__rit)
    98			{
    99			  if (__it == __rit)
   100			    return false;
   101			}
   102	
   103		      return true;
   104		    }
   105	
   106		  const _Source& _M_source;
   107		};
   108	
   109	      template<typename _Source, typename _InvalidatePred>
   110		struct _UContMergeGuard
   111		{
   112		  _UContMergeGuard(_Source& __src) noexcept
   113		  : _M_source(__src), _M_size(__src.size()), _M_pred { __src }
   114		  { }
   115	
   116		  _UContMergeGuard(const _UContMergeGuard&) = delete;
   117	
   118		  ~_UContMergeGuard()
   119		  {
   120		    const std::size_t __size = _M_source.size();
   121		    if (__size == _M_size)
   122		      return;
   123	
   124		    __try
   125		      {
   126			if (__size == 0)
   127			  _M_source._M_invalidate_all();
   128			else
   129			  {
   130			    _M_source._M_invalidate_if(_M_pred);
   131			    _M_source._M_invalidate_local_if(_M_pred);
   132			  }
   133		      }
   134		    __catch(...)
   135		      {
   136			_M_source._M_invalidate_all();
   137		      }
   138		  }
   139	
   140		  _Source& _M_source;
   141		  const std::size_t _M_size;
   142		  _InvalidatePred _M_pred;
   143		};
   144	
   145	      template<typename _ExtractKey, typename _Source>
   146		static _UContMergeGuard<_Source,
   147					_UContInvalidatePred<_ExtractKey, _Source>>
   148		_S_uc_guard(_ExtractKey, _Source& __src)
   149		{
   150		  typedef _UContInvalidatePred<_ExtractKey, _Source> _InvalidatePred;
   151		  return _UContMergeGuard<_Source, _InvalidatePred>(__src);
   152		}
   153	
   154	      template<typename _ExtractKey, typename _Source>
   155		static _UContMergeGuard<_Source,
   156					_UMContInvalidatePred<_ExtractKey, _Source>>
   157		_S_umc_guard(_ExtractKey, _Source& __src)
   158		{
   159		  typedef _UMContInvalidatePred<_ExtractKey, _Source> _InvalidatePred;
   160		  return _UContMergeGuard<_Source, _InvalidatePred>(__src);
   161		}
   162	#endif // C++17
   163	
   164	    public:
   165	      void
   166	      _M_invalidate_all()
   167	      {
   168		auto __end = _M_cont()._M_base().cend();
   169		this->_M_invalidate_if([__end](__decltype(__end) __it)
   170				       { return __it != __end; });
   171		_M_invalidate_locals();
   172	      }
   173	
   174	      /** Invalidates all iterators @c x that reference this container,
   175		  are not singular, and for which @c __pred(x) returns @c
   176		  true. @c __pred will be invoked with the normal iterators nested
   177		  in the safe ones. */
   178	      template<typename _Predicate>
   179		void
   180		_M_invalidate_if(_Predicate __pred);
   181	
   182	      /** Invalidates all local iterators @c x that reference this container,
   183		  are not singular, and for which @c __pred(x) returns @c
   184		  true. @c __pred will be invoked with the normal local iterators
   185		  nested in the safe ones. */
   186	      template<typename _Predicate>
   187		void
   188		_M_invalidate_local_if(_Predicate __pred);
   189	    };
   190	} // namespace __gnu_debug
   191	
   192	#include <debug/safe_unordered_container.tcc>
   193	
   194	#endif
Welcome to MyWebUniversity on April 15, 2025.
