safe_sequence.tcc

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// Safe sequence implementation  -*- C++ -*-
 
// Copyright (C) 2010-2025 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
 
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
 
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
 
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
// <http://www.gnu.org/licenses/>.
 
/** @file debug/safe_sequence.tcc
 *  This file is a GNU debug extension to the Standard C++ Library.
 */
 
#ifndef _GLIBCXX_DEBUG_SAFE_SEQUENCE_TCC
#define _GLIBCXX_DEBUG_SAFE_SEQUENCE_TCC 1
 
namespace __gnu_debug
{
  template<typename _Sequence>
    template<typename _Predicate>
      _GLIBCXX20_CONSTEXPR void
      _Safe_sequence<_Sequence>::
      _M_invalidate_if(_Predicate __pred) const
      {
        if (std::__is_constant_evaluated())
          return;
 
        typedef typename _Sequence::iterator iterator;
        typedef typename _Sequence::const_iterator const_iterator;
 
        __gnu_cxx::__scoped_lock sentry(this->_M_get_mutex());
        for (_Safe_iterator_base* __iter = _M_iterators; __iter;)
          {
            iterator* __victim = static_cast<iterator*>(__iter);
            __iter = __iter->_M_next;
            if (!__victim->_M_singular() && __pred(__victim->base()))
              {
                __victim->_M_invalidate();
              }
          }
 
        for (_Safe_iterator_base* __iter2 = _M_const_iterators; __iter2;)
          {
            const_iterator* __victim = static_cast<const_iterator*>(__iter2);
            __iter2 = __iter2->_M_next;
            if (!__victim->_M_singular() && __pred(__victim->base()))
              {
                __victim->_M_invalidate();
              }
          }
      }
 
  template<typename _Sequence>
    template<typename _Predicate>
      void
      _Safe_sequence<_Sequence>::
      _M_transfer_from_if(const _Safe_sequence& __from, _Predicate __pred) const
      {
        if (this == std::__addressof(__from))
          return;
 
        typedef typename _Sequence::iterator iterator;
        typedef typename _Sequence::const_iterator const_iterator;
 
        _Safe_iterator_base* __transfered_iterators = 0;
        _Safe_iterator_base* __transfered_const_iterators = 0;
        _Safe_iterator_base* __last_iterator = 0;
        _Safe_iterator_base* __last_const_iterator = 0;
        {
          // We lock __from first and detach iterator(s) to transfer
          __gnu_cxx::__scoped_lock sentry(__from._M_get_mutex());
 
          for (_Safe_iterator_base* __iter = __from._M_iterators; __iter;)
            {
              _Safe_iterator_base* __victim_base = __iter;
              iterator* __victim = static_cast<iterator*>(__victim_base);
              __iter = __iter->_M_next;
              if (!__victim->_M_singular() && __pred(__victim->base()))
                {
                  __victim->_M_detach_single();
                  if (__transfered_iterators)
                    {
                      __victim_base->_M_next = __transfered_iterators;
                      __transfered_iterators->_M_prior = __victim_base;
                    }
                  else
                    __last_iterator = __victim_base;
                  __victim_base->_M_sequence = this;
                  __victim_base->_M_version = this->_M_version;
                  __transfered_iterators = __victim_base;
                }
            }
 
          for (_Safe_iterator_base* __iter2 = __from._M_const_iterators;
               __iter2;)
            {
              _Safe_iterator_base* __victim_base = __iter2;
              const_iterator* __victim =
                static_cast<const_iterator*>(__victim_base);
              __iter2 = __iter2->_M_next;
              if (!__victim->_M_singular() && __pred(__victim->base()))
                {
                  __victim->_M_detach_single();
                  if (__transfered_const_iterators)
                    {
                      __victim_base->_M_next = __transfered_const_iterators;
                      __transfered_const_iterators->_M_prior = __victim_base;
                    }
                  else
                    __last_const_iterator = __victim;
                  __victim_base->_M_sequence = this;
                  __victim_base->_M_version = this->_M_version;
                  __transfered_const_iterators = __victim_base;
                }
            }
        }
 
        // Now we can lock *this and add the transfered iterators if any
        if (__last_iterator || __last_const_iterator)
          {
            __gnu_cxx::__scoped_lock sentry(this->_M_get_mutex());
            if (__last_iterator)
              {
                if (this->_M_iterators)
                  {
                    this->_M_iterators->_M_prior = __last_iterator;
                    __last_iterator->_M_next = this->_M_iterators;
                  }
                this->_M_iterators = __transfered_iterators;
              }
            if (__last_const_iterator)
              {
                if (this->_M_const_iterators)
                  {
                    this->_M_const_iterators->_M_prior = __last_const_iterator;
                    __last_const_iterator->_M_next = this->_M_const_iterators;
                  }
                this->_M_const_iterators = __transfered_const_iterators;
              }
          }
      }
} // namespace __gnu_debug
 
#endif