boost/interprocess/allocators/detail/allocator_common.hpp
//////////////////////////////////////////////////////////////////////////////
//
// (C) Copyright Ion Gaztanaga 2008. 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
#include <boost/interprocess/detail/config_begin.hpp>
#include <boost/interprocess/detail/workaround.hpp>
#include <boost/pointer_to_other.hpp>
#include <boost/interprocess/interprocess_fwd.hpp>
#include <boost/interprocess/detail/utilities.hpp> //get_pointer
#include <utility> //std::pair
#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/interprocess/mem_algo/detail/mem_algo_common.hpp>
#include <boost/interprocess/detail/segment_manager_helper.hpp>
#include <algorithm> //std::swap
#include <boost/interprocess/detail/move.hpp>
#include <boost/interprocess/detail/type_traits.hpp>
#include <boost/interprocess/detail/utilities.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 detail {
//!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)
{
detail::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 pointer_to_other
<void_pointer, NodePool>::type node_pool_ptr;
typedef typename NodePool::multiallocation_chain multiallocation_chain;
node_pool_ptr mp_node_pool;
multiallocation_chain m_cached_nodes;
std::size_t m_max_cached_nodes;
public:
typedef typename NodePool::segment_manager segment_manager;
cache_impl(segment_manager *segment_mngr, std::size_t 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();
detail::destroy_node_pool_if_last_link(detail::get_pointer(mp_node_pool));
}
NodePool *get_node_pool() const
{ return detail::get_pointer(mp_node_pool); }
segment_manager *get_segment_manager() const
{ return mp_node_pool->get_segment_manager(); }
std::size_t 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()){
m_cached_nodes = mp_node_pool->allocate_nodes(m_max_cached_nodes/2);
}
void *ret = detail::get_pointer(m_cached_nodes.front());
m_cached_nodes.pop_front();
return ret;
}
multiallocation_chain cached_allocation(std::size_t n)
{
multiallocation_chain chain;
std::size_t 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 = detail::get_pointer(m_cached_nodes.front());
m_cached_nodes.pop_front();
chain.push_back(ret);
++allocated;
}
if(allocated != n){
multiallocation_chain chain2(mp_node_pool->allocate_nodes(n - allocated));
chain.splice_after(chain.last(), chain2, chain2.before_begin(), chain2.last(), n - allocated);
}
return boost::interprocess::move(chain);
}
BOOST_CATCH(...){
this->cached_deallocation(boost::interprocess::move(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(std::size_t 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(boost::interprocess::move(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(std::size_t n)
{
//Deallocate all new linked list at once
mp_node_pool->deallocate_nodes(m_cached_nodes, n);
}
};
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::
pointer_to_other<void_pointer, T>::type pointer;
typedef typename boost::
pointer_to_other<void_pointer, const T>::type const_pointer;
typedef T value_type;
typedef typename detail::add_reference
<value_type>::type reference;
typedef typename detail::add_reference
<const value_type>::type const_reference;
typedef std::size_t size_type;
typedef std::ptrdiff_t difference_type;
typedef 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(detail::get_pointer(p))/sizeof(T);
}
std::pair<pointer, bool>
allocation_command(boost::interprocess::allocation_type command,
size_type limit_size,
size_type preferred_size,
size_type &received_size, const pointer &reuse = 0)
{
return this->derived()->get_segment_manager()->allocation_command
(command, limit_size, preferred_size, received_size, detail::get_pointer(reuse));
}
//!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(...)
multiallocation_chain allocate_many(size_type elem_size, std::size_t num_elements)
{
return this->derived()->get_segment_manager()->allocate_many(sizeof(T)*elem_size, num_elements);
}
//!Allocates n_elements elements, each one of size elem_sizes[i]in a
//!contiguous block
//!of memory. The elements must be deallocated
multiallocation_chain allocate_many(const size_type *elem_sizes, size_type n_elements)
{
return this->derived()->get_segment_manager()->allocate_many(elem_sizes, n_elements, sizeof(T));
}
//!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)
{ return this->derived()->get_segment_manager()->deallocate_many(boost::interprocess::move(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)); }
//!Default construct an object.
//!Throws if T's default constructor throws
void construct(const pointer &ptr)
{ new((void*)detail::get_pointer(ptr)) value_type; }
//!Copy construct an object
//!Throws if T's copy constructor throws
void construct(const pointer &ptr, const_reference v)
{ new((void*)detail::get_pointer(ptr)) value_type(v); }
//!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::
pointer_to_other<void_pointer, const void>::type cvoid_pointer;
public:
typedef typename boost::
pointer_to_other<void_pointer, T>::type pointer;
typedef typename boost::
pointer_to_other<void_pointer, const T>::type const_pointer;
typedef T value_type;
typedef typename detail::add_reference
<value_type>::type reference;
typedef typename detail::add_reference
<const value_type>::type const_reference;
typedef std::size_t size_type;
typedef std::ptrdiff_t difference_type;
typedef 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(count > this->max_size())
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(sizeof(T)*count)));
}
//!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(detail::get_pointer(ptr));
else
pool->get_segment_manager()->deallocate((void*)detail::get_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().
multiallocation_chain allocate_individual(std::size_t num_elements)
{
typedef typename node_pool<0>::type node_pool_t;
node_pool_t *pool = node_pool<0>::get(this->derived()->get_node_pool());
return multiallocation_chain(pool->allocate_nodes(num_elements));
}
//!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(detail::get_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.extract_multiallocation_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::
pointer_to_other<void_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:
enum { DEFAULT_MAX_CACHED_NODES = 64 };
cached_allocator_impl(segment_manager *segment_mngr, std::size_t 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(std::size_t newmax)
{ m_cache.set_max_cached_nodes(newmax); }
//!Returns the max cached nodes parameter.
//!Never throws
std::size_t 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(count > this->max_size())
throw bad_alloc();
else if(Version == 1 && count == 1){
ret = m_cache.cached_allocation();
}
else{
ret = this->get_segment_manager()->allocate(sizeof(T)*count);
}
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(detail::get_pointer(ptr));
}
else{
this->get_segment_manager()->deallocate((void*)detail::get_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().
multiallocation_chain allocate_individual(std::size_t num_elements)
{ return multiallocation_chain(this->m_cache.cached_allocation(num_elements)); }
//!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(detail::get_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)
{
typename node_pool_t::multiallocation_chain mem
(chain.extract_multiallocation_chain());
m_cache.cached_deallocation(boost::interprocess::move(mem));
}
//!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)
{
detail::do_swap(alloc1.mp_node_pool, alloc2.mp_node_pool);
alloc1.m_cached_nodes.swap(alloc2.m_cached_nodes);
detail::do_swap(alloc1.m_max_cached_nodes, alloc2.m_max_cached_nodes);
}
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(); }
/// @cond
private:
cache_impl<node_pool_t> m_cache;
};
//!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;
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 a singly linked list of n nodes ending in null pointer.
//!can throw boost::interprocess::bad_alloc
void allocate_nodes(multiallocation_chain &nodes, std::size_t n)
{
//-----------------------
boost::interprocess::scoped_lock<mutex_type> guard(m_header);
//-----------------------
return private_node_allocator_t::allocate_nodes(nodes, n);
}
*/
//!Allocates n nodes.
//!Can throw boost::interprocess::bad_alloc
multiallocation_chain allocate_nodes(const std::size_t n)
{
//-----------------------
boost::interprocess::scoped_lock<mutex_type> guard(m_header);
//-----------------------
return private_node_allocator_t::allocate_nodes(n);
}
//!Deallocates a linked list of nodes ending in null pointer. Never throws
void deallocate_nodes(multiallocation_chain &nodes, std::size_t 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(boost::interprocess::move(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
std::size_t 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
std::size_t dec_ref_count()
{
//-----------------------
boost::interprocess::scoped_lock<mutex_type> guard(m_header);
//-----------------------
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
//!interprocess_mutex to allow EBO when using null_mutex
struct header_t : mutex_type
{
std::size_t m_usecount; //Number of attached allocators
header_t()
: m_usecount(0) {}
} m_header;
};
} //namespace detail {
} //namespace interprocess {
} //namespace boost {
#include <boost/interprocess/detail/config_end.hpp>
#endif //#ifndef BOOST_INTERPROCESS_ALLOCATOR_DETAIL_ALLOCATOR_COMMON_HPP