boost/interprocess/allocators/detail/allocator_common.hpp
////////////////////////////////////////////////////////////////////////////// // // (C) Copyright Ion Gaztanaga 2008-2012. Distributed under the Boost // Software License, Version 1.0. (See accompanying file // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) // // See http://www.boost.org/libs/interprocess for documentation. // ////////////////////////////////////////////////////////////////////////////// #ifndef BOOST_INTERPROCESS_ALLOCATOR_DETAIL_ALLOCATOR_COMMON_HPP #define BOOST_INTERPROCESS_ALLOCATOR_DETAIL_ALLOCATOR_COMMON_HPP #ifndef BOOST_CONFIG_HPP # include <boost/config.hpp> #endif # #if defined(BOOST_HAS_PRAGMA_ONCE) # pragma once #endif #include <boost/interprocess/detail/config_begin.hpp> #include <boost/interprocess/detail/workaround.hpp> #include <boost/intrusive/pointer_traits.hpp> #include <boost/interprocess/interprocess_fwd.hpp> #include <boost/interprocess/detail/utilities.hpp> //to_raw_pointer #include <boost/utility/addressof.hpp> //boost::addressof #include <boost/assert.hpp> //BOOST_ASSERT #include <boost/interprocess/exceptions.hpp> //bad_alloc #include <boost/interprocess/sync/scoped_lock.hpp> //scoped_lock #include <boost/interprocess/containers/allocation_type.hpp> //boost::interprocess::allocation_type #include <boost/container/detail/multiallocation_chain.hpp> #include <boost/interprocess/mem_algo/detail/mem_algo_common.hpp> #include <boost/interprocess/detail/segment_manager_helper.hpp> #include <boost/move/utility_core.hpp> #include <boost/interprocess/detail/type_traits.hpp> #include <boost/interprocess/detail/utilities.hpp> #include <boost/container/detail/placement_new.hpp> #include <boost/move/adl_move_swap.hpp> namespace boost { namespace interprocess { template <class T> struct sizeof_value { static const std::size_t value = sizeof(T); }; template <> struct sizeof_value<void> { static const std::size_t value = sizeof(void*); }; template <> struct sizeof_value<const void> { static const std::size_t value = sizeof(void*); }; template <> struct sizeof_value<volatile void> { static const std::size_t value = sizeof(void*); }; template <> struct sizeof_value<const volatile void> { static const std::size_t value = sizeof(void*); }; namespace ipcdetail { //!Object function that creates the node allocator if it is not created and //!increments reference count if it is already created template<class NodePool> struct get_or_create_node_pool_func { //!This connects or constructs the unique instance of node_pool_t //!Can throw boost::interprocess::bad_alloc void operator()() { //Find or create the node_pool_t mp_node_pool = mp_segment_manager->template find_or_construct <NodePool>(boost::interprocess::unique_instance)(mp_segment_manager); //If valid, increment link count if(mp_node_pool != 0) mp_node_pool->inc_ref_count(); } //!Constructor. Initializes function //!object parameters get_or_create_node_pool_func(typename NodePool::segment_manager *mngr) : mp_segment_manager(mngr){} NodePool *mp_node_pool; typename NodePool::segment_manager *mp_segment_manager; }; template<class NodePool> inline NodePool *get_or_create_node_pool(typename NodePool::segment_manager *mgnr) { ipcdetail::get_or_create_node_pool_func<NodePool> func(mgnr); mgnr->atomic_func(func); return func.mp_node_pool; } //!Object function that decrements the reference count. If the count //!reaches to zero destroys the node allocator from memory. //!Never throws template<class NodePool> struct destroy_if_last_link_func { //!Decrements reference count and destroys the object if there is no //!more attached allocators. Never throws void operator()() { //If not the last link return if(mp_node_pool->dec_ref_count() != 0) return; //Last link, let's destroy the segment_manager mp_node_pool->get_segment_manager()->template destroy<NodePool>(boost::interprocess::unique_instance); } //!Constructor. Initializes function //!object parameters destroy_if_last_link_func(NodePool *pool) : mp_node_pool(pool) {} NodePool *mp_node_pool; }; //!Destruction function, initializes and executes destruction function //!object. Never throws template<class NodePool> inline void destroy_node_pool_if_last_link(NodePool *pool) { //Get segment manager typename NodePool::segment_manager *mngr = pool->get_segment_manager(); //Execute destruction functor atomically destroy_if_last_link_func<NodePool>func(pool); mngr->atomic_func(func); } template<class NodePool> class cache_impl { typedef typename NodePool::segment_manager:: void_pointer void_pointer; typedef typename boost::intrusive:: pointer_traits<void_pointer>::template rebind_pointer<NodePool>::type node_pool_ptr; typedef typename NodePool::multiallocation_chain multiallocation_chain; typedef typename NodePool::segment_manager::size_type size_type; node_pool_ptr mp_node_pool; multiallocation_chain m_cached_nodes; size_type m_max_cached_nodes; public: typedef typename NodePool::segment_manager segment_manager; cache_impl(segment_manager *segment_mngr, size_type max_cached_nodes) : mp_node_pool(get_or_create_node_pool<NodePool>(segment_mngr)) , m_max_cached_nodes(max_cached_nodes) {} cache_impl(const cache_impl &other) : mp_node_pool(other.get_node_pool()) , m_max_cached_nodes(other.get_max_cached_nodes()) { mp_node_pool->inc_ref_count(); } ~cache_impl() { this->deallocate_all_cached_nodes(); ipcdetail::destroy_node_pool_if_last_link(ipcdetail::to_raw_pointer(mp_node_pool)); } NodePool *get_node_pool() const { return ipcdetail::to_raw_pointer(mp_node_pool); } segment_manager *get_segment_manager() const { return mp_node_pool->get_segment_manager(); } size_type get_max_cached_nodes() const { return m_max_cached_nodes; } void *cached_allocation() { //If don't have any cached node, we have to get a new list of free nodes from the pool if(m_cached_nodes.empty()){ mp_node_pool->allocate_nodes(m_max_cached_nodes/2, m_cached_nodes); } void *ret = ipcdetail::to_raw_pointer(m_cached_nodes.pop_front()); return ret; } void cached_allocation(size_type n, multiallocation_chain &chain) { size_type count = n, allocated(0); BOOST_TRY{ //If don't have any cached node, we have to get a new list of free nodes from the pool while(!m_cached_nodes.empty() && count--){ void *ret = ipcdetail::to_raw_pointer(m_cached_nodes.pop_front()); chain.push_back(ret); ++allocated; } if(allocated != n){ mp_node_pool->allocate_nodes(n - allocated, chain); } } BOOST_CATCH(...){ this->cached_deallocation(chain); BOOST_RETHROW } BOOST_CATCH_END } void cached_deallocation(void *ptr) { //Check if cache is full if(m_cached_nodes.size() >= m_max_cached_nodes){ //This only occurs if this allocator deallocate memory allocated //with other equal allocator. Since the cache is full, and more //deallocations are probably coming, we'll make some room in cache //in a single, efficient multi node deallocation. this->priv_deallocate_n_nodes(m_cached_nodes.size() - m_max_cached_nodes/2); } m_cached_nodes.push_front(ptr); } void cached_deallocation(multiallocation_chain &chain) { m_cached_nodes.splice_after(m_cached_nodes.before_begin(), chain); //Check if cache is full if(m_cached_nodes.size() >= m_max_cached_nodes){ //This only occurs if this allocator deallocate memory allocated //with other equal allocator. Since the cache is full, and more //deallocations are probably coming, we'll make some room in cache //in a single, efficient multi node deallocation. this->priv_deallocate_n_nodes(m_cached_nodes.size() - m_max_cached_nodes/2); } } //!Sets the new max cached nodes value. This can provoke deallocations //!if "newmax" is less than current cached nodes. Never throws void set_max_cached_nodes(size_type newmax) { m_max_cached_nodes = newmax; this->priv_deallocate_remaining_nodes(); } //!Frees all cached nodes. //!Never throws void deallocate_all_cached_nodes() { if(m_cached_nodes.empty()) return; mp_node_pool->deallocate_nodes(m_cached_nodes); } private: //!Frees all cached nodes at once. //!Never throws void priv_deallocate_remaining_nodes() { if(m_cached_nodes.size() > m_max_cached_nodes){ priv_deallocate_n_nodes(m_cached_nodes.size()-m_max_cached_nodes); } } //!Frees n cached nodes at once. Never throws void priv_deallocate_n_nodes(size_type n) { //This only occurs if this allocator deallocate memory allocated //with other equal allocator. Since the cache is full, and more //deallocations are probably coming, we'll make some room in cache //in a single, efficient multi node deallocation. size_type count(n); typename multiallocation_chain::iterator it(m_cached_nodes.before_begin()); while(count--){ ++it; } multiallocation_chain chain; chain.splice_after(chain.before_begin(), m_cached_nodes, m_cached_nodes.before_begin(), it, n); //Deallocate all new linked list at once mp_node_pool->deallocate_nodes(chain); } public: void swap(cache_impl &other) { ::boost::adl_move_swap(mp_node_pool, other.mp_node_pool); ::boost::adl_move_swap(m_cached_nodes, other.m_cached_nodes); ::boost::adl_move_swap(m_max_cached_nodes, other.m_max_cached_nodes); } }; template<class Derived, class T, class SegmentManager> class array_allocation_impl { const Derived *derived() const { return static_cast<const Derived*>(this); } Derived *derived() { return static_cast<Derived*>(this); } typedef typename SegmentManager::void_pointer void_pointer; public: typedef typename boost::intrusive:: pointer_traits<void_pointer>::template rebind_pointer<T>::type pointer; typedef typename boost::intrusive:: pointer_traits<void_pointer>::template rebind_pointer<const T>::type const_pointer; typedef T value_type; typedef typename ipcdetail::add_reference <value_type>::type reference; typedef typename ipcdetail::add_reference <const value_type>::type const_reference; typedef typename SegmentManager::size_type size_type; typedef typename SegmentManager::difference_type difference_type; typedef boost::container::container_detail::transform_multiallocation_chain <typename SegmentManager::multiallocation_chain, T>multiallocation_chain; public: //!Returns maximum the number of objects the previously allocated memory //!pointed by p can hold. This size only works for memory allocated with //!allocate, allocation_command and allocate_many. size_type size(const pointer &p) const { return (size_type)this->derived()->get_segment_manager()->size(ipcdetail::to_raw_pointer(p))/sizeof(T); } pointer allocation_command(boost::interprocess::allocation_type command, size_type limit_size, size_type &prefer_in_recvd_out_size, pointer &reuse) { value_type *reuse_raw = ipcdetail::to_raw_pointer(reuse); pointer const p = this->derived()->get_segment_manager()->allocation_command (command, limit_size, prefer_in_recvd_out_size, reuse_raw); reuse = reuse_raw; return p; } //!Allocates many elements of size elem_size in a contiguous block //!of memory. The minimum number to be allocated is min_elements, //!the preferred and maximum number is //!preferred_elements. The number of actually allocated elements is //!will be assigned to received_size. The elements must be deallocated //!with deallocate(...) void allocate_many(size_type elem_size, size_type num_elements, multiallocation_chain &chain) { if(size_overflows<sizeof(T)>(elem_size)){ throw bad_alloc(); } this->derived()->get_segment_manager()->allocate_many(elem_size*sizeof(T), num_elements, chain); } //!Allocates n_elements elements, each one of size elem_sizes[i]in a //!contiguous block //!of memory. The elements must be deallocated void allocate_many(const size_type *elem_sizes, size_type n_elements, multiallocation_chain &chain) { this->derived()->get_segment_manager()->allocate_many(elem_sizes, n_elements, sizeof(T), chain); } //!Allocates many elements of size elem_size in a contiguous block //!of memory. The minimum number to be allocated is min_elements, //!the preferred and maximum number is //!preferred_elements. The number of actually allocated elements is //!will be assigned to received_size. The elements must be deallocated //!with deallocate(...) void deallocate_many(multiallocation_chain &chain) { this->derived()->get_segment_manager()->deallocate_many(chain); } //!Returns the number of elements that could be //!allocated. Never throws size_type max_size() const { return this->derived()->get_segment_manager()->get_size()/sizeof(T); } //!Returns address of mutable object. //!Never throws pointer address(reference value) const { return pointer(boost::addressof(value)); } //!Returns address of non mutable object. //!Never throws const_pointer address(const_reference value) const { return const_pointer(boost::addressof(value)); } //!Constructs an object //!Throws if T's constructor throws //!For backwards compatibility with libraries using C++03 allocators template<class P> void construct(const pointer &ptr, BOOST_FWD_REF(P) p) { ::new((void*)ipcdetail::to_raw_pointer(ptr), boost_container_new_t()) value_type(::boost::forward<P>(p)); } //!Destroys object. Throws if object's //!destructor throws void destroy(const pointer &ptr) { BOOST_ASSERT(ptr != 0); (*ptr).~value_type(); } }; template<class Derived, unsigned int Version, class T, class SegmentManager> class node_pool_allocation_impl : public array_allocation_impl < Derived , T , SegmentManager> { const Derived *derived() const { return static_cast<const Derived*>(this); } Derived *derived() { return static_cast<Derived*>(this); } typedef typename SegmentManager::void_pointer void_pointer; typedef typename boost::intrusive:: pointer_traits<void_pointer>::template rebind_pointer<const void>::type cvoid_pointer; public: typedef typename boost::intrusive:: pointer_traits<void_pointer>::template rebind_pointer<T>::type pointer; typedef typename boost::intrusive:: pointer_traits<void_pointer>::template rebind_pointer<const T>::type const_pointer; typedef T value_type; typedef typename ipcdetail::add_reference <value_type>::type reference; typedef typename ipcdetail::add_reference <const value_type>::type const_reference; typedef typename SegmentManager::size_type size_type; typedef typename SegmentManager::difference_type difference_type; typedef boost::container::container_detail::transform_multiallocation_chain <typename SegmentManager::multiallocation_chain, T>multiallocation_chain; template <int Dummy> struct node_pool { typedef typename Derived::template node_pool<0>::type type; static type *get(void *p) { return static_cast<type*>(p); } }; public: //!Allocate memory for an array of count elements. //!Throws boost::interprocess::bad_alloc if there is no enough memory pointer allocate(size_type count, cvoid_pointer hint = 0) { (void)hint; typedef typename node_pool<0>::type node_pool_t; node_pool_t *pool = node_pool<0>::get(this->derived()->get_node_pool()); if(size_overflows<sizeof(T)>(count)){ throw bad_alloc(); } else if(Version == 1 && count == 1){ return pointer(static_cast<value_type*> (pool->allocate_node())); } else{ return pointer(static_cast<value_type*> (pool->get_segment_manager()->allocate(count*sizeof(T)))); } } //!Deallocate allocated memory. Never throws void deallocate(const pointer &ptr, size_type count) { (void)count; typedef typename node_pool<0>::type node_pool_t; node_pool_t *pool = node_pool<0>::get(this->derived()->get_node_pool()); if(Version == 1 && count == 1) pool->deallocate_node(ipcdetail::to_raw_pointer(ptr)); else pool->get_segment_manager()->deallocate((void*)ipcdetail::to_raw_pointer(ptr)); } //!Allocates just one object. Memory allocated with this function //!must be deallocated only with deallocate_one(). //!Throws boost::interprocess::bad_alloc if there is no enough memory pointer allocate_one() { typedef typename node_pool<0>::type node_pool_t; node_pool_t *pool = node_pool<0>::get(this->derived()->get_node_pool()); return pointer(static_cast<value_type*>(pool->allocate_node())); } //!Allocates many elements of size == 1 in a contiguous block //!of memory. The minimum number to be allocated is min_elements, //!the preferred and maximum number is //!preferred_elements. The number of actually allocated elements is //!will be assigned to received_size. Memory allocated with this function //!must be deallocated only with deallocate_one(). void allocate_individual(size_type num_elements, multiallocation_chain &chain) { typedef typename node_pool<0>::type node_pool_t; node_pool_t *pool = node_pool<0>::get(this->derived()->get_node_pool()); pool->allocate_nodes(num_elements, chain); } //!Deallocates memory previously allocated with allocate_one(). //!You should never use deallocate_one to deallocate memory allocated //!with other functions different from allocate_one(). Never throws void deallocate_one(const pointer &p) { typedef typename node_pool<0>::type node_pool_t; node_pool_t *pool = node_pool<0>::get(this->derived()->get_node_pool()); pool->deallocate_node(ipcdetail::to_raw_pointer(p)); } //!Allocates many elements of size == 1 in a contiguous block //!of memory. The minimum number to be allocated is min_elements, //!the preferred and maximum number is //!preferred_elements. The number of actually allocated elements is //!will be assigned to received_size. Memory allocated with this function //!must be deallocated only with deallocate_one(). void deallocate_individual(multiallocation_chain &chain) { node_pool<0>::get(this->derived()->get_node_pool())->deallocate_nodes (chain); } //!Deallocates all free blocks of the pool void deallocate_free_blocks() { node_pool<0>::get(this->derived()->get_node_pool())->deallocate_free_blocks(); } //!Deprecated, use deallocate_free_blocks. //!Deallocates all free chunks of the pool. void deallocate_free_chunks() { node_pool<0>::get(this->derived()->get_node_pool())->deallocate_free_blocks(); } }; template<class T, class NodePool, unsigned int Version> class cached_allocator_impl : public array_allocation_impl <cached_allocator_impl<T, NodePool, Version>, T, typename NodePool::segment_manager> { cached_allocator_impl & operator=(const cached_allocator_impl& other); typedef array_allocation_impl < cached_allocator_impl <T, NodePool, Version> , T , typename NodePool::segment_manager> base_t; public: typedef NodePool node_pool_t; typedef typename NodePool::segment_manager segment_manager; typedef typename segment_manager::void_pointer void_pointer; typedef typename boost::intrusive:: pointer_traits<void_pointer>::template rebind_pointer<const void>::type cvoid_pointer; typedef typename base_t::pointer pointer; typedef typename base_t::size_type size_type; typedef typename base_t::multiallocation_chain multiallocation_chain; typedef typename base_t::value_type value_type; public: static const std::size_t DEFAULT_MAX_CACHED_NODES = 64; cached_allocator_impl(segment_manager *segment_mngr, size_type max_cached_nodes) : m_cache(segment_mngr, max_cached_nodes) {} cached_allocator_impl(const cached_allocator_impl &other) : m_cache(other.m_cache) {} //!Copy constructor from related cached_adaptive_pool_base. If not present, constructs //!a node pool. Increments the reference count of the associated node pool. //!Can throw boost::interprocess::bad_alloc template<class T2, class NodePool2> cached_allocator_impl (const cached_allocator_impl <T2, NodePool2, Version> &other) : m_cache(other.get_segment_manager(), other.get_max_cached_nodes()) {} //!Returns a pointer to the node pool. //!Never throws node_pool_t* get_node_pool() const { return m_cache.get_node_pool(); } //!Returns the segment manager. //!Never throws segment_manager* get_segment_manager()const { return m_cache.get_segment_manager(); } //!Sets the new max cached nodes value. This can provoke deallocations //!if "newmax" is less than current cached nodes. Never throws void set_max_cached_nodes(size_type newmax) { m_cache.set_max_cached_nodes(newmax); } //!Returns the max cached nodes parameter. //!Never throws size_type get_max_cached_nodes() const { return m_cache.get_max_cached_nodes(); } //!Allocate memory for an array of count elements. //!Throws boost::interprocess::bad_alloc if there is no enough memory pointer allocate(size_type count, cvoid_pointer hint = 0) { (void)hint; void * ret; if(size_overflows<sizeof(T)>(count)){ throw bad_alloc(); } else if(Version == 1 && count == 1){ ret = m_cache.cached_allocation(); } else{ ret = this->get_segment_manager()->allocate(count*sizeof(T)); } return pointer(static_cast<T*>(ret)); } //!Deallocate allocated memory. Never throws void deallocate(const pointer &ptr, size_type count) { (void)count; if(Version == 1 && count == 1){ m_cache.cached_deallocation(ipcdetail::to_raw_pointer(ptr)); } else{ this->get_segment_manager()->deallocate((void*)ipcdetail::to_raw_pointer(ptr)); } } //!Allocates just one object. Memory allocated with this function //!must be deallocated only with deallocate_one(). //!Throws boost::interprocess::bad_alloc if there is no enough memory pointer allocate_one() { return pointer(static_cast<value_type*>(this->m_cache.cached_allocation())); } //!Allocates many elements of size == 1 in a contiguous block //!of memory. The minimum number to be allocated is min_elements, //!the preferred and maximum number is //!preferred_elements. The number of actually allocated elements is //!will be assigned to received_size. Memory allocated with this function //!must be deallocated only with deallocate_one(). void allocate_individual(size_type num_elements, multiallocation_chain &chain) { this->m_cache.cached_allocation(num_elements, chain); } //!Deallocates memory previously allocated with allocate_one(). //!You should never use deallocate_one to deallocate memory allocated //!with other functions different from allocate_one(). Never throws void deallocate_one(const pointer &p) { this->m_cache.cached_deallocation(ipcdetail::to_raw_pointer(p)); } //!Allocates many elements of size == 1 in a contiguous block //!of memory. The minimum number to be allocated is min_elements, //!the preferred and maximum number is //!preferred_elements. The number of actually allocated elements is //!will be assigned to received_size. Memory allocated with this function //!must be deallocated only with deallocate_one(). void deallocate_individual(multiallocation_chain &chain) { m_cache.cached_deallocation(chain); } //!Deallocates all free blocks of the pool void deallocate_free_blocks() { m_cache.get_node_pool()->deallocate_free_blocks(); } //!Swaps allocators. Does not throw. If each allocator is placed in a //!different shared memory segments, the result is undefined. friend void swap(cached_allocator_impl &alloc1, cached_allocator_impl &alloc2) { ::boost::adl_move_swap(alloc1.m_cache, alloc2.m_cache); } void deallocate_cache() { m_cache.deallocate_all_cached_nodes(); } //!Deprecated use deallocate_free_blocks. void deallocate_free_chunks() { m_cache.get_node_pool()->deallocate_free_blocks(); } #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED) private: cache_impl<node_pool_t> m_cache; #endif //!defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED) }; //!Equality test for same type of //!cached_allocator_impl template<class T, class N, unsigned int V> inline bool operator==(const cached_allocator_impl<T, N, V> &alloc1, const cached_allocator_impl<T, N, V> &alloc2) { return alloc1.get_node_pool() == alloc2.get_node_pool(); } //!Inequality test for same type of //!cached_allocator_impl template<class T, class N, unsigned int V> inline bool operator!=(const cached_allocator_impl<T, N, V> &alloc1, const cached_allocator_impl<T, N, V> &alloc2) { return alloc1.get_node_pool() != alloc2.get_node_pool(); } //!Pooled shared memory allocator using adaptive pool. Includes //!a reference count but the class does not delete itself, this is //!responsibility of user classes. Node size (NodeSize) and the number of //!nodes allocated per block (NodesPerBlock) are known at compile time template<class private_node_allocator_t> class shared_pool_impl : public private_node_allocator_t { public: //!Segment manager typedef typedef typename private_node_allocator_t:: segment_manager segment_manager; typedef typename private_node_allocator_t:: multiallocation_chain multiallocation_chain; typedef typename private_node_allocator_t:: size_type size_type; private: typedef typename segment_manager::mutex_family::mutex_type mutex_type; public: //!Constructor from a segment manager. Never throws shared_pool_impl(segment_manager *segment_mngr) : private_node_allocator_t(segment_mngr) {} //!Destructor. Deallocates all allocated blocks. Never throws ~shared_pool_impl() {} //!Allocates array of count elements. Can throw boost::interprocess::bad_alloc void *allocate_node() { //----------------------- boost::interprocess::scoped_lock<mutex_type> guard(m_header); //----------------------- return private_node_allocator_t::allocate_node(); } //!Deallocates an array pointed by ptr. Never throws void deallocate_node(void *ptr) { //----------------------- boost::interprocess::scoped_lock<mutex_type> guard(m_header); //----------------------- private_node_allocator_t::deallocate_node(ptr); } //!Allocates n nodes. //!Can throw boost::interprocess::bad_alloc void allocate_nodes(const size_type n, multiallocation_chain &chain) { //----------------------- boost::interprocess::scoped_lock<mutex_type> guard(m_header); //----------------------- private_node_allocator_t::allocate_nodes(n, chain); } //!Deallocates a linked list of nodes ending in null pointer. Never throws void deallocate_nodes(multiallocation_chain &nodes, size_type num) { //----------------------- boost::interprocess::scoped_lock<mutex_type> guard(m_header); //----------------------- private_node_allocator_t::deallocate_nodes(nodes, num); } //!Deallocates the nodes pointed by the multiallocation iterator. Never throws void deallocate_nodes(multiallocation_chain &chain) { //----------------------- boost::interprocess::scoped_lock<mutex_type> guard(m_header); //----------------------- private_node_allocator_t::deallocate_nodes(chain); } //!Deallocates all the free blocks of memory. Never throws void deallocate_free_blocks() { //----------------------- boost::interprocess::scoped_lock<mutex_type> guard(m_header); //----------------------- private_node_allocator_t::deallocate_free_blocks(); } //!Deallocates all used memory from the common pool. //!Precondition: all nodes allocated from this pool should //!already be deallocated. Otherwise, undefined behavior. Never throws void purge_blocks() { //----------------------- boost::interprocess::scoped_lock<mutex_type> guard(m_header); //----------------------- private_node_allocator_t::purge_blocks(); } //!Increments internal reference count and returns new count. Never throws size_type inc_ref_count() { //----------------------- boost::interprocess::scoped_lock<mutex_type> guard(m_header); //----------------------- return ++m_header.m_usecount; } //!Decrements internal reference count and returns new count. Never throws size_type dec_ref_count() { //----------------------- boost::interprocess::scoped_lock<mutex_type> guard(m_header); //----------------------- BOOST_ASSERT(m_header.m_usecount > 0); return --m_header.m_usecount; } //!Deprecated, use deallocate_free_blocks. void deallocate_free_chunks() { //----------------------- boost::interprocess::scoped_lock<mutex_type> guard(m_header); //----------------------- private_node_allocator_t::deallocate_free_blocks(); } //!Deprecated, use purge_blocks. void purge_chunks() { //----------------------- boost::interprocess::scoped_lock<mutex_type> guard(m_header); //----------------------- private_node_allocator_t::purge_blocks(); } private: //!This struct includes needed data and derives from //!the mutex type to allow EBO when using null_mutex struct header_t : mutex_type { size_type m_usecount; //Number of attached allocators header_t() : m_usecount(0) {} } m_header; }; } //namespace ipcdetail { } //namespace interprocess { } //namespace boost { #include <boost/interprocess/detail/config_end.hpp> #endif //#ifndef BOOST_INTERPROCESS_ALLOCATOR_DETAIL_ALLOCATOR_COMMON_HPP