williamr@2: /* Copyright 2003-2006 Joaquín M López Muñoz.
williamr@2:  * Distributed under the Boost Software License, Version 1.0.
williamr@2:  * (See accompanying file LICENSE_1_0.txt or copy at
williamr@2:  * http://www.boost.org/LICENSE_1_0.txt)
williamr@2:  *
williamr@2:  * See http://www.boost.org/libs/multi_index for library home page.
williamr@2:  */
williamr@2: 
williamr@2: #ifndef BOOST_MULTI_INDEX_DETAIL_SAFE_MODE_HPP
williamr@2: #define BOOST_MULTI_INDEX_DETAIL_SAFE_MODE_HPP
williamr@2: 
williamr@2: #if defined(_MSC_VER)&&(_MSC_VER>=1200)
williamr@2: #pragma once
williamr@2: #endif
williamr@2: 
williamr@2: /* Safe mode machinery, in the spirit of Cay Hortmann's "Safe STL"
williamr@2:  * (http://www.horstmann.com/safestl.html).
williamr@2:  * In this mode, containers of type Container are derived from
williamr@2:  * safe_container<Container>, and their corresponding iterators
williamr@2:  * are wrapped with safe_iterator. These classes provide
williamr@2:  * an internal record of which iterators are at a given moment associated
williamr@2:  * to a given container, and properly mark the iterators as invalid
williamr@2:  * when the container gets destroyed.
williamr@2:  * Iterators are chained in a single attached list, whose header is
williamr@2:  * kept by the container. More elaborate data structures would yield better
williamr@2:  * performance, but I decided to keep complexity to a minimum since
williamr@2:  * speed is not an issue here.
williamr@2:  * Safe mode iterators automatically check that only proper operations
williamr@2:  * are performed on them: for instance, an invalid iterator cannot be
williamr@2:  * dereferenced. Additionally, a set of utilty macros and functions are
williamr@2:  * provided that serve to implement preconditions and cooperate with
williamr@2:  * the framework within the container.
williamr@2:  * Iterators can also be unchecked, i.e. they do not have info about
williamr@2:  * which container they belong in. This situation arises when the iterator
williamr@2:  * is restored from a serialization archive: only information on the node
williamr@2:  * is available, and it is not possible to determine to which container
williamr@2:  * the iterator is associated to. The only sensible policy is to assume
williamr@2:  * unchecked iterators are valid, though this can certainly generate false
williamr@2:  * positive safe mode checks.
williamr@2:  * This is not a full-fledged safe mode framework, and is only intended
williamr@2:  * for use within the limits of Boost.MultiIndex.
williamr@2:  */
williamr@2: 
williamr@2: /* Assertion macros. These resolve to no-ops if
williamr@2:  * !defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE).
williamr@2:  */
williamr@2: 
williamr@2: #if !defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
williamr@2: #undef BOOST_MULTI_INDEX_SAFE_MODE_ASSERT
williamr@2: #define BOOST_MULTI_INDEX_SAFE_MODE_ASSERT(expr,error_code) ((void)0)
williamr@2: #else
williamr@2: #if !defined(BOOST_MULTI_INDEX_SAFE_MODE_ASSERT)
williamr@2: #include <boost/assert.hpp>
williamr@2: #define BOOST_MULTI_INDEX_SAFE_MODE_ASSERT(expr,error_code) BOOST_ASSERT(expr)
williamr@2: #endif
williamr@2: #endif
williamr@2: 
williamr@2: #define BOOST_MULTI_INDEX_CHECK_VALID_ITERATOR(it)                           \
williamr@2:   BOOST_MULTI_INDEX_SAFE_MODE_ASSERT(                                        \
williamr@2:     safe_mode::check_valid_iterator(it),                                     \
williamr@2:     safe_mode::invalid_iterator);
williamr@2: 
williamr@2: #define BOOST_MULTI_INDEX_CHECK_DEREFERENCEABLE_ITERATOR(it)                 \
williamr@2:   BOOST_MULTI_INDEX_SAFE_MODE_ASSERT(                                        \
williamr@2:     safe_mode::check_dereferenceable_iterator(it),                           \
williamr@2:     safe_mode::not_dereferenceable_iterator);
williamr@2: 
williamr@2: #define BOOST_MULTI_INDEX_CHECK_INCREMENTABLE_ITERATOR(it)                   \
williamr@2:   BOOST_MULTI_INDEX_SAFE_MODE_ASSERT(                                        \
williamr@2:     safe_mode::check_incrementable_iterator(it),                             \
williamr@2:     safe_mode::not_incrementable_iterator);
williamr@2: 
williamr@2: #define BOOST_MULTI_INDEX_CHECK_DECREMENTABLE_ITERATOR(it)                   \
williamr@2:   BOOST_MULTI_INDEX_SAFE_MODE_ASSERT(                                        \
williamr@2:     safe_mode::check_decrementable_iterator(it),                             \
williamr@2:     safe_mode::not_decrementable_iterator);
williamr@2: 
williamr@2: #define BOOST_MULTI_INDEX_CHECK_IS_OWNER(it,cont)                            \
williamr@2:   BOOST_MULTI_INDEX_SAFE_MODE_ASSERT(                                        \
williamr@2:     safe_mode::check_is_owner(it,cont),                                      \
williamr@2:     safe_mode::not_owner);
williamr@2: 
williamr@2: #define BOOST_MULTI_INDEX_CHECK_SAME_OWNER(it0,it1)                          \
williamr@2:   BOOST_MULTI_INDEX_SAFE_MODE_ASSERT(                                        \
williamr@2:     safe_mode::check_same_owner(it0,it1),                                    \
williamr@2:     safe_mode::not_same_owner);
williamr@2: 
williamr@2: #define BOOST_MULTI_INDEX_CHECK_VALID_RANGE(it0,it1)                         \
williamr@2:   BOOST_MULTI_INDEX_SAFE_MODE_ASSERT(                                        \
williamr@2:     safe_mode::check_valid_range(it0,it1),                                   \
williamr@2:     safe_mode::invalid_range);
williamr@2: 
williamr@2: #define BOOST_MULTI_INDEX_CHECK_OUTSIDE_RANGE(it,it0,it1)                    \
williamr@2:   BOOST_MULTI_INDEX_SAFE_MODE_ASSERT(                                        \
williamr@2:     safe_mode::check_outside_range(it,it0,it1),                              \
williamr@2:     safe_mode::inside_range);
williamr@2: 
williamr@2: #define BOOST_MULTI_INDEX_CHECK_IN_BOUNDS(it,n)                              \
williamr@2:   BOOST_MULTI_INDEX_SAFE_MODE_ASSERT(                                        \
williamr@2:     safe_mode::check_in_bounds(it,n),                                        \
williamr@2:     safe_mode::out_of_bounds);
williamr@2: 
williamr@2: #define BOOST_MULTI_INDEX_CHECK_DIFFERENT_CONTAINER(cont0,cont1)             \
williamr@2:   BOOST_MULTI_INDEX_SAFE_MODE_ASSERT(                                        \
williamr@2:     safe_mode::check_different_container(cont0,cont1),                       \
williamr@2:     safe_mode::same_container);
williamr@2: 
williamr@2: #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
williamr@2: #include <boost/config.hpp> /* keep it first to prevent nasty warns in MSVC */
williamr@2: #include <algorithm>
williamr@2: #include <boost/detail/iterator.hpp>
williamr@2: #include <boost/multi_index/detail/access_specifier.hpp>
williamr@2: #include <boost/multi_index/detail/iter_adaptor.hpp>
williamr@2: #include <boost/multi_index/safe_mode_errors.hpp>
williamr@2: #include <boost/noncopyable.hpp>
williamr@2: 
williamr@2: #if !defined(BOOST_MULTI_INDEX_DISABLE_SERIALIZATION)
williamr@2: #include <boost/serialization/split_member.hpp>
williamr@2: #endif
williamr@2: 
williamr@2: #if defined(BOOST_HAS_THREADS)
williamr@2: #include <boost/detail/lightweight_mutex.hpp>
williamr@2: #endif
williamr@2: 
williamr@2: namespace boost{
williamr@2: 
williamr@2: namespace multi_index{
williamr@2: 
williamr@2: namespace safe_mode{
williamr@2: 
williamr@2: /* Checking routines. Assume the best for unchecked iterators
williamr@2:  * (i.e. they pass the checking when there is not enough info
williamr@2:  * to know.)
williamr@2:  */
williamr@2: 
williamr@2: template<typename Iterator>
williamr@2: inline bool check_valid_iterator(const Iterator& it)
williamr@2: {
williamr@2:   return it.valid()||it.unchecked();
williamr@2: }
williamr@2: 
williamr@2: template<typename Iterator>
williamr@2: inline bool check_dereferenceable_iterator(const Iterator& it)
williamr@2: {
williamr@2:   return it.valid()&&it!=it.owner()->end()||it.unchecked();
williamr@2: }
williamr@2: 
williamr@2: template<typename Iterator>
williamr@2: inline bool check_incrementable_iterator(const Iterator& it)
williamr@2: {
williamr@2:   return it.valid()&&it!=it.owner()->end()||it.unchecked();
williamr@2: }
williamr@2: 
williamr@2: template<typename Iterator>
williamr@2: inline bool check_decrementable_iterator(const Iterator& it)
williamr@2: {
williamr@2:   return it.valid()&&it!=it.owner()->begin()||it.unchecked();
williamr@2: }
williamr@2: 
williamr@2: template<typename Iterator>
williamr@2: inline bool check_is_owner(
williamr@2:   const Iterator& it,const typename Iterator::container_type& cont)
williamr@2: {
williamr@2:   return it.valid()&&it.owner()==&cont||it.unchecked();
williamr@2: }
williamr@2: 
williamr@2: template<typename Iterator>
williamr@2: inline bool check_same_owner(const Iterator& it0,const Iterator& it1)
williamr@2: {
williamr@2:   return it0.valid()&&it1.valid()&&it0.owner()==it1.owner()||
williamr@2:          it0.unchecked()||it1.unchecked();
williamr@2: }
williamr@2: 
williamr@2: template<typename Iterator>
williamr@2: inline bool check_valid_range(const Iterator& it0,const Iterator& it1)
williamr@2: {
williamr@2:   if(!check_same_owner(it0,it1))return false;
williamr@2: 
williamr@2:   if(it0.valid()){
williamr@2:     Iterator last=it0.owner()->end();
williamr@2:     if(it1==last)return true;
williamr@2: 
williamr@2:     for(Iterator first=it0;first!=last;++first){
williamr@2:       if(first==it1)return true;
williamr@2:     }
williamr@2:     return false;
williamr@2:   }
williamr@2:   return true;
williamr@2: }
williamr@2: 
williamr@2: template<typename Iterator>
williamr@2: inline bool check_outside_range(
williamr@2:   const Iterator& it,const Iterator& it0,const Iterator& it1)
williamr@2: {
williamr@2:   if(!check_same_owner(it0,it1))return false;
williamr@2: 
williamr@2:   if(it0.valid()){
williamr@2:     Iterator last=it0.owner()->end();
williamr@2:     bool found=false;
williamr@2: 
williamr@2:     Iterator first=it0;
williamr@2:     for(;first!=last;++first){
williamr@2:       if(first==it1)break;
williamr@2:     
williamr@2:       /* crucial that this check goes after previous break */
williamr@2:     
williamr@2:       if(first==it)found=true;
williamr@2:     }
williamr@2:     if(first!=it1)return false;
williamr@2:     return !found;
williamr@2:   }
williamr@2:   return true;
williamr@2: }
williamr@2: 
williamr@2: template<typename Iterator,typename Difference>
williamr@2: inline bool check_in_bounds(const Iterator& it,Difference n)
williamr@2: {
williamr@2:   if(it.unchecked())return true;
williamr@2:   if(!it.valid())   return false;
williamr@2:   if(n>0)           return it.owner()->end()-it>=n;
williamr@2:   else              return it.owner()->begin()-it<=n;
williamr@2: }
williamr@2: 
williamr@2: template<typename Container>
williamr@2: inline bool check_different_container(
williamr@2:   const Container& cont0,const Container& cont1)
williamr@2: {
williamr@2:   return &cont0!=&cont1;
williamr@2: }
williamr@2: 
williamr@2: /* Invalidates all iterators equivalent to that given. Safe containers
williamr@2:  * must call this when deleting elements: the safe mode framework cannot
williamr@2:  * perform this operation automatically without outside help.
williamr@2:  */
williamr@2: 
williamr@2: template<typename Iterator>
williamr@2: inline void detach_equivalent_iterators(Iterator& it)
williamr@2: {
williamr@2:   if(it.valid()){
williamr@2:     Iterator *prev_,*next_;
williamr@2:     for(
williamr@2:       prev_=static_cast<Iterator*>(&it.cont->header);
williamr@2:       (next_=static_cast<Iterator*>(prev_->next))!=0;){
williamr@2:       if(next_!=&it&&*next_==it){
williamr@2:         prev_->next=next_->next;
williamr@2:         next_->cont=0;
williamr@2:       }
williamr@2:       else prev_=next_;
williamr@2:     }
williamr@2:     it.detach();
williamr@2:   }
williamr@2: }
williamr@2: 
williamr@2: template<typename Container> class safe_container; /* fwd decl. */
williamr@2: 
williamr@2: } /* namespace multi_index::safe_mode */
williamr@2: 
williamr@2: namespace detail{
williamr@2: 
williamr@2: class safe_container_base;                 /* fwd decl. */
williamr@2: 
williamr@2: class safe_iterator_base
williamr@2: {
williamr@2: public:
williamr@2:   bool valid()const{return cont!=0;}
williamr@2:   bool unchecked()const{return unchecked_;}
williamr@2: 
williamr@2:   inline void detach();
williamr@2: 
williamr@2:   void uncheck()
williamr@2:   {
williamr@2:     detach();
williamr@2:     unchecked_=true;
williamr@2:   }
williamr@2: 
williamr@2: protected:
williamr@2:   safe_iterator_base():cont(0),next(0),unchecked_(false){}
williamr@2: 
williamr@2:   explicit safe_iterator_base(safe_container_base* cont_):
williamr@2:     unchecked_(false)
williamr@2:   {
williamr@2:     attach(cont_);
williamr@2:   }
williamr@2: 
williamr@2:   safe_iterator_base(const safe_iterator_base& it):
williamr@2:     unchecked_(it.unchecked_)
williamr@2:   {
williamr@2:     attach(it.cont);
williamr@2:   }
williamr@2: 
williamr@2:   safe_iterator_base& operator=(const safe_iterator_base& it)
williamr@2:   {
williamr@2:     unchecked_=it.unchecked_;
williamr@2:     safe_container_base* new_cont=it.cont;
williamr@2:     if(cont!=new_cont){
williamr@2:       detach();
williamr@2:       attach(new_cont);
williamr@2:     }
williamr@2:     return *this;
williamr@2:   }
williamr@2: 
williamr@2:   ~safe_iterator_base()
williamr@2:   {
williamr@2:     detach();
williamr@2:   }
williamr@2: 
williamr@2:   const safe_container_base* owner()const{return cont;}
williamr@2: 
williamr@2: BOOST_MULTI_INDEX_PRIVATE_IF_MEMBER_TEMPLATE_FRIENDS:
williamr@2:   friend class safe_container_base;
williamr@2: 
williamr@2: #if !defined(BOOST_NO_MEMBER_TEMPLATE_FRIENDS)
williamr@2:   template<typename>          friend class safe_mode::safe_container;
williamr@2:   template<typename Iterator> friend
williamr@2:     void safe_mode::detach_equivalent_iterators(Iterator&);
williamr@2: #endif
williamr@2: 
williamr@2:   inline void attach(safe_container_base* cont_);
williamr@2: 
williamr@2:   safe_container_base* cont;
williamr@2:   safe_iterator_base*  next;
williamr@2:   bool                 unchecked_;
williamr@2: };
williamr@2: 
williamr@2: class safe_container_base:private noncopyable
williamr@2: {
williamr@2: public:
williamr@2:   safe_container_base(){}
williamr@2: 
williamr@2: BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
williamr@2:   friend class safe_iterator_base;
williamr@2: 
williamr@2: #if !defined(BOOST_NO_MEMBER_TEMPLATE_FRIENDS)
williamr@2:   template<typename Iterator> friend
williamr@2:     void safe_mode::detach_equivalent_iterators(Iterator&);
williamr@2: #endif
williamr@2: 
williamr@2:   ~safe_container_base()
williamr@2:   {
williamr@2:     /* Detaches all remaining iterators, which by now will
williamr@2:      * be those pointing to the end of the container.
williamr@2:      */
williamr@2: 
williamr@2:     for(safe_iterator_base* it=header.next;it;it=it->next)it->cont=0;
williamr@2:     header.next=0;
williamr@2:   }
williamr@2: 
williamr@2:   void swap(safe_container_base& x)
williamr@2:   {
williamr@2:     for(safe_iterator_base* it0=header.next;it0;it0=it0->next)it0->cont=&x;
williamr@2:     for(safe_iterator_base* it1=x.header.next;it1;it1=it1->next)it1->cont=this;
williamr@2:     std::swap(header.cont,x.header.cont);
williamr@2:     std::swap(header.next,x.header.next);
williamr@2:   }
williamr@2: 
williamr@2:   safe_iterator_base header;
williamr@2: 
williamr@2: #if defined(BOOST_HAS_THREADS)
williamr@2:   boost::detail::lightweight_mutex mutex;
williamr@2: #endif
williamr@2: };
williamr@2: 
williamr@2: void safe_iterator_base::attach(safe_container_base* cont_)
williamr@2: {
williamr@2:   cont=cont_;
williamr@2:   if(cont){
williamr@2: #if defined(BOOST_HAS_THREADS)
williamr@2:     boost::detail::lightweight_mutex::scoped_lock lock(cont->mutex);
williamr@2: #endif
williamr@2: 
williamr@2:     next=cont->header.next;
williamr@2:     cont->header.next=this;
williamr@2:   }
williamr@2: }
williamr@2: 
williamr@2: void safe_iterator_base::detach()
williamr@2: {
williamr@2:   if(cont){
williamr@2: #if defined(BOOST_HAS_THREADS)
williamr@2:     boost::detail::lightweight_mutex::scoped_lock lock(cont->mutex);
williamr@2: #endif
williamr@2: 
williamr@2:     safe_iterator_base *prev_,*next_;
williamr@2:     for(prev_=&cont->header;(next_=prev_->next)!=this;prev_=next_){}
williamr@2:     prev_->next=next;
williamr@2:     cont=0;
williamr@2:   }
williamr@2: }
williamr@2: 
williamr@2: } /* namespace multi_index::detail */
williamr@2: 
williamr@2: namespace safe_mode{
williamr@2: 
williamr@2: /* In order to enable safe mode on a container:
williamr@2:  *   - The container must derive from safe_container<container_type>,
williamr@2:  *   - iterators must be generated via safe_iterator, which adapts a
williamr@2:  *     preexistent unsafe iterator class.
williamr@2:  */
williamr@2:  
williamr@2: template<typename Container>
williamr@2: class safe_container;
williamr@2: 
williamr@2: template<typename Iterator,typename Container>
williamr@2: class safe_iterator:
williamr@2:   public detail::iter_adaptor<safe_iterator<Iterator,Container>,Iterator>,
williamr@2:   public detail::safe_iterator_base
williamr@2: {
williamr@2:   typedef detail::iter_adaptor<safe_iterator,Iterator> super;
williamr@2:   typedef detail::safe_iterator_base                   safe_super;
williamr@2: 
williamr@2: public:
williamr@2:   typedef Container                                    container_type;
williamr@2:   typedef typename Iterator::reference                 reference;
williamr@2:   typedef typename Iterator::difference_type           difference_type;
williamr@2: 
williamr@2:   safe_iterator(){}
williamr@2:   explicit safe_iterator(safe_container<container_type>* cont_):
williamr@2:     safe_super(cont_){}
williamr@2:   template<typename T0>
williamr@2:   safe_iterator(const T0& t0,safe_container<container_type>* cont_):
williamr@2:     super(Iterator(t0)),safe_super(cont_){}
williamr@2:   template<typename T0,typename T1>
williamr@2:   safe_iterator(
williamr@2:     const T0& t0,const T1& t1,safe_container<container_type>* cont_):
williamr@2:     super(Iterator(t0,t1)),safe_super(cont_){}
williamr@2: 
williamr@2:   safe_iterator& operator=(const safe_iterator& x)
williamr@2:   {
williamr@2:     BOOST_MULTI_INDEX_CHECK_VALID_ITERATOR(x);
williamr@2:     this->base_reference()=x.base_reference();
williamr@2:     safe_super::operator=(x);
williamr@2:     return *this;
williamr@2:   }
williamr@2: 
williamr@2:   const container_type* owner()const
williamr@2:   {
williamr@2:     return
williamr@2:       static_cast<const container_type*>(
williamr@2:         static_cast<const safe_container<container_type>*>(
williamr@2:           this->safe_super::owner()));
williamr@2:   }
williamr@2: 
williamr@2:   /* get_node is not to be used by the user */
williamr@2: 
williamr@2:   typedef typename Iterator::node_type node_type;
williamr@2: 
williamr@2:   node_type* get_node()const{return this->base_reference().get_node();}
williamr@2: 
williamr@2: private:
williamr@2:   friend class boost::multi_index::detail::iter_adaptor_access;
williamr@2: 
williamr@2:   reference dereference()const
williamr@2:   {
williamr@2:     BOOST_MULTI_INDEX_CHECK_VALID_ITERATOR(*this);
williamr@2:     BOOST_MULTI_INDEX_CHECK_DEREFERENCEABLE_ITERATOR(*this);
williamr@2:     return *(this->base_reference());
williamr@2:   }
williamr@2: 
williamr@2:   bool equal(const safe_iterator& x)const
williamr@2:   {
williamr@2:     BOOST_MULTI_INDEX_CHECK_VALID_ITERATOR(*this);
williamr@2:     BOOST_MULTI_INDEX_CHECK_VALID_ITERATOR(x);
williamr@2:     BOOST_MULTI_INDEX_CHECK_SAME_OWNER(*this,x);
williamr@2:     return this->base_reference()==x.base_reference();
williamr@2:   }
williamr@2: 
williamr@2:   void increment()
williamr@2:   {
williamr@2:     BOOST_MULTI_INDEX_CHECK_VALID_ITERATOR(*this);
williamr@2:     BOOST_MULTI_INDEX_CHECK_INCREMENTABLE_ITERATOR(*this);
williamr@2:     ++(this->base_reference());
williamr@2:   }
williamr@2: 
williamr@2:   void decrement()
williamr@2:   {
williamr@2:     BOOST_MULTI_INDEX_CHECK_VALID_ITERATOR(*this);
williamr@2:     BOOST_MULTI_INDEX_CHECK_DECREMENTABLE_ITERATOR(*this);
williamr@2:     --(this->base_reference());
williamr@2:   }
williamr@2: 
williamr@2:   void advance(difference_type n)
williamr@2:   {
williamr@2:     BOOST_MULTI_INDEX_CHECK_VALID_ITERATOR(*this);
williamr@2:     BOOST_MULTI_INDEX_CHECK_IN_BOUNDS(*this,n);
williamr@2:     this->base_reference()+=n;
williamr@2:   }
williamr@2: 
williamr@2:   difference_type distance_to(const safe_iterator& x)const
williamr@2:   {
williamr@2:     BOOST_MULTI_INDEX_CHECK_VALID_ITERATOR(*this);
williamr@2:     BOOST_MULTI_INDEX_CHECK_VALID_ITERATOR(x);
williamr@2:     BOOST_MULTI_INDEX_CHECK_SAME_OWNER(*this,x);
williamr@2:     return x.base_reference()-this->base_reference();
williamr@2:   }
williamr@2: 
williamr@2: #if !defined(BOOST_MULTI_INDEX_DISABLE_SERIALIZATION)
williamr@2:   /* Serialization. Note that Iterator::save and Iterator:load
williamr@2:    * are assumed to be defined and public: at first sight it seems
williamr@2:    * like we could have resorted to the public serialization interface
williamr@2:    * for doing the forwarding to the adapted iterator class:
williamr@2:    *   ar<<base_reference();
williamr@2:    *   ar>>base_reference();
williamr@2:    * but this would cause incompatibilities if a saving
williamr@2:    * program is in safe mode and the loading program is not, or
williamr@2:    * viceversa --in safe mode, the archived iterator data is one layer
williamr@2:    * deeper, this is especially relevant with XML archives.
williamr@2:    * It'd be nice if Boost.Serialization provided some forwarding
williamr@2:    * facility for use by adaptor classes.
williamr@2:    */ 
williamr@2: 
williamr@2:   friend class boost::serialization::access;
williamr@2: 
williamr@2:   BOOST_SERIALIZATION_SPLIT_MEMBER()
williamr@2: 
williamr@2:   template<class Archive>
williamr@2:   void save(Archive& ar,const unsigned int version)const
williamr@2:   {
williamr@2:     BOOST_MULTI_INDEX_CHECK_VALID_ITERATOR(*this);
williamr@2:     this->base_reference().save(ar,version);
williamr@2:   }
williamr@2: 
williamr@2:   template<class Archive>
williamr@2:   void load(Archive& ar,const unsigned int version)
williamr@2:   {
williamr@2:     this->base_reference().load(ar,version);
williamr@2:     safe_super::uncheck();
williamr@2:   }
williamr@2: #endif
williamr@2: };
williamr@2: 
williamr@2: template<typename Container>
williamr@2: class safe_container:public detail::safe_container_base
williamr@2: {
williamr@2:   typedef detail::safe_container_base super;
williamr@2: 
williamr@2: public:
williamr@2:   void detach_dereferenceable_iterators()
williamr@2:   {
williamr@2:     typedef typename Container::iterator iterator;
williamr@2: 
williamr@2:     iterator end_=static_cast<Container*>(this)->end();
williamr@2:     iterator *prev_,*next_;
williamr@2:     for(
williamr@2:       prev_=static_cast<iterator*>(&this->header);
williamr@2:       (next_=static_cast<iterator*>(prev_->next))!=0;){
williamr@2:       if(*next_!=end_){
williamr@2:         prev_->next=next_->next;
williamr@2:         next_->cont=0;
williamr@2:       }
williamr@2:       else prev_=next_;
williamr@2:     }
williamr@2:   }
williamr@2: 
williamr@2:   void swap(safe_container<Container>& x)
williamr@2:   {
williamr@2:     super::swap(x);
williamr@2:   }
williamr@2: };
williamr@2: 
williamr@2: } /* namespace multi_index::safe_mode */
williamr@2: 
williamr@2: } /* namespace multi_index */
williamr@2: 
williamr@2: } /* namespace boost */
williamr@2: 
williamr@2: #endif /* BOOST_MULTI_INDEX_ENABLE_SAFE_MODE */
williamr@2: 
williamr@2: #endif