boost/interprocess/detail/managed_memory_impl.hpp
//////////////////////////////////////////////////////////////////////////////
//
// (C) Copyright Ion Gaztanaga 2005-2012. 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_DETAIL_MANAGED_MEMORY_IMPL_HPP
#define BOOST_INTERPROCESS_DETAIL_MANAGED_MEMORY_IMPL_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/interprocess/interprocess_fwd.hpp>
#include <boost/interprocess/detail/utilities.hpp>
#include <boost/interprocess/detail/os_file_functions.hpp>
#include <boost/interprocess/creation_tags.hpp>
#include <boost/interprocess/exceptions.hpp>
#include <boost/interprocess/segment_manager.hpp>
#include <boost/interprocess/sync/scoped_lock.hpp>
#include <boost/interprocess/detail/nothrow.hpp>
#include <boost/interprocess/detail/simple_swap.hpp>
//
#include <boost/core/no_exceptions_support.hpp>
//
#include <boost/intrusive/detail/minimal_pair_header.hpp>
#include <boost/assert.hpp>
//!\file
//!Describes a named shared memory allocation user class.
//!
namespace boost {
namespace interprocess {
namespace ipcdetail {
template<class BasicManagedMemoryImpl>
class create_open_func;
template<
class CharType,
class MemoryAlgorithm,
template<class IndexConfig> class IndexType
>
struct segment_manager_type
{
typedef segment_manager<CharType, MemoryAlgorithm, IndexType> type;
};
//!This class is designed to be a base class to classes that manage
//!creation of objects in a fixed size memory buffer. Apart
//!from allocating raw memory, the user can construct named objects. To
//!achieve this, this class uses the reserved space provided by the allocation
//!algorithm to place a named_allocator_algo, who takes care of name mappings.
//!The class can be customized with the char type used for object names
//!and the memory allocation algorithm to be used.*/
template < class CharType
, class MemoryAlgorithm
, template<class IndexConfig> class IndexType
, std::size_t Offset = 0
>
class basic_managed_memory_impl
{
//Non-copyable
basic_managed_memory_impl(const basic_managed_memory_impl &);
basic_managed_memory_impl &operator=(const basic_managed_memory_impl &);
template<class BasicManagedMemoryImpl>
friend class create_open_func;
public:
typedef typename segment_manager_type
<CharType, MemoryAlgorithm, IndexType>::type segment_manager;
typedef CharType char_type;
typedef MemoryAlgorithm memory_algorithm;
typedef typename MemoryAlgorithm::mutex_family mutex_family;
typedef CharType char_t;
typedef typename MemoryAlgorithm::size_type size_type;
typedef typename MemoryAlgorithm::difference_type difference_type;
typedef difference_type handle_t;
typedef typename segment_manager::
const_named_iterator const_named_iterator;
typedef typename segment_manager::
const_unique_iterator const_unique_iterator;
#if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED)
typedef typename
segment_manager::char_ptr_holder_t char_ptr_holder_t;
//Experimental. Don't use.
typedef typename segment_manager::multiallocation_chain multiallocation_chain;
#endif //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED
static const size_type PayloadPerAllocation = segment_manager::PayloadPerAllocation;
private:
typedef basic_managed_memory_impl
<CharType, MemoryAlgorithm, IndexType, Offset> self_t;
protected:
template<class ManagedMemory>
static bool grow(const char *filename, size_type extra_bytes)
{
typedef typename ManagedMemory::device_type device_type;
//Increase file size
try{
offset_t old_size;
{
device_type f(open_or_create, filename, read_write);
if(!f.get_size(old_size))
return false;
f.truncate(old_size + extra_bytes);
}
ManagedMemory managed_memory(open_only, filename);
//Grow always works
managed_memory.self_t::grow(extra_bytes);
}
catch(...){
return false;
}
return true;
}
template<class ManagedMemory>
static bool shrink_to_fit(const char *filename)
{
typedef typename ManagedMemory::device_type device_type;
size_type new_size;
try{
ManagedMemory managed_memory(open_only, filename);
managed_memory.get_size();
managed_memory.self_t::shrink_to_fit();
new_size = managed_memory.get_size();
}
catch(...){
return false;
}
//Decrease file size
{
device_type f(open_or_create, filename, read_write);
f.truncate(new_size);
}
return true;
}
//!Constructor. Allocates basic resources. Never throws.
basic_managed_memory_impl()
: mp_header(0){}
//!Destructor. Calls close. Never throws.
~basic_managed_memory_impl()
{ this->close_impl(); }
//!Places segment manager in the reserved space. This can throw.
bool create_impl (void *addr, size_type size)
{
if(mp_header) return false;
//Check if there is enough space
if(size < segment_manager::get_min_size())
return false;
//This function should not throw. The index construction can
//throw if constructor allocates memory. So we must catch it.
BOOST_TRY{
//Let's construct the allocator in memory
mp_header = ::new(addr, boost_container_new_t()) segment_manager(size);
}
BOOST_CATCH(...){
return false;
}
BOOST_CATCH_END
return true;
}
//!Connects to a segment manager in the reserved buffer. Never throws.
bool open_impl (void *addr, size_type)
{
if(mp_header) return false;
mp_header = static_cast<segment_manager*>(addr);
return true;
}
//!Frees resources. Never throws.
bool close_impl()
{
bool ret = mp_header != 0;
mp_header = 0;
return ret;
}
//!Frees resources and destroys common resources. Never throws.
bool destroy_impl()
{
if(mp_header == 0)
return false;
mp_header->~segment_manager();
this->close_impl();
return true;
}
//!
void grow(size_type extra_bytes)
{ mp_header->grow(extra_bytes); }
void shrink_to_fit()
{ mp_header->shrink_to_fit(); }
public:
//!Returns segment manager. Never throws.
segment_manager *get_segment_manager() const
{ return mp_header; }
//!Returns the base address of the memory in this process. Never throws.
void * get_address () const
{ return reinterpret_cast<char*>(mp_header) - Offset; }
//!Returns the size of memory segment. Never throws.
size_type get_size () const
{ return mp_header->get_size() + Offset; }
//!Returns the number of free bytes of the memory
//!segment
size_type get_free_memory() const
{ return mp_header->get_free_memory(); }
//!Returns the result of "all_memory_deallocated()" function
//!of the used memory algorithm
bool all_memory_deallocated()
{ return mp_header->all_memory_deallocated(); }
//!Returns the result of "check_sanity()" function
//!of the used memory algorithm
bool check_sanity()
{ return mp_header->check_sanity(); }
//!Writes to zero free memory (memory not yet allocated) of
//!the memory algorithm
void zero_free_memory()
{ mp_header->zero_free_memory(); }
//!Transforms an absolute address into an offset from base address.
//!The address must belong to the memory segment. Never throws.
handle_t get_handle_from_address (const void *ptr) const
{
return (handle_t)(reinterpret_cast<const char*>(ptr) -
reinterpret_cast<const char*>(this->get_address()));
}
//!Returns true if the address belongs to the managed memory segment
bool belongs_to_segment (const void *ptr) const
{
return ptr >= this->get_address() &&
ptr < (reinterpret_cast<const char*>(this->get_address()) + this->get_size());
}
//!Transforms previously obtained offset into an absolute address in the
//!process space of the current process. Never throws.*/
void * get_address_from_handle (handle_t offset) const
{ return reinterpret_cast<char*>(this->get_address()) + offset; }
//!Searches for nbytes of free memory in the segment, marks the
//!memory as used and return the pointer to the memory. If no
//!memory is available throws a boost::interprocess::bad_alloc exception
void* allocate (size_type nbytes)
{ return mp_header->allocate(nbytes); }
//!Searches for nbytes of free memory in the segment, marks the
//!memory as used and return the pointer to the memory. If no memory
//!is available returns 0. Never throws.
void* allocate (size_type nbytes, const std::nothrow_t &tag)
{ return mp_header->allocate(nbytes, tag); }
//!Allocates nbytes bytes aligned to "alignment" bytes. "alignment"
//!must be power of two. If no memory
//!is available returns 0. Never throws.
void * allocate_aligned (size_type nbytes, size_type alignment, const std::nothrow_t &tag)
{ return mp_header->allocate_aligned(nbytes, alignment, tag); }
template<class T>
T * allocation_command (boost::interprocess::allocation_type command, size_type limit_size,
size_type &prefer_in_recvd_out_size, T *&reuse)
{ return mp_header->allocation_command(command, limit_size, prefer_in_recvd_out_size, reuse); }
//!Allocates nbytes bytes aligned to "alignment" bytes. "alignment"
//!must be power of two. If no
//!memory is available throws a boost::interprocess::bad_alloc exception
void * allocate_aligned(size_type nbytes, size_type alignment)
{ return mp_header->allocate_aligned(nbytes, alignment); }
#if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED)
//Experimental. Don't use.
//!Allocates n_elements of elem_bytes bytes.
//!Throws bad_alloc on failure. chain.size() is not increased on failure.
void allocate_many(size_type elem_bytes, size_type n_elements, multiallocation_chain &chain)
{ mp_header->allocate_many(elem_bytes, n_elements, chain); }
//!Allocates n_elements, each one of element_lengths[i]*sizeof_element bytes.
//!Throws bad_alloc on failure. chain.size() is not increased on failure.
void allocate_many(const size_type *element_lengths, size_type n_elements, size_type sizeof_element, multiallocation_chain &chain)
{ mp_header->allocate_many(element_lengths, n_elements, sizeof_element, chain); }
//!Allocates n_elements of elem_bytes bytes.
//!Non-throwing version. chain.size() is not increased on failure.
void allocate_many(const std::nothrow_t &tag, size_type elem_bytes, size_type n_elements, multiallocation_chain &chain)
{ mp_header->allocate_many(tag, elem_bytes, n_elements, chain); }
//!Allocates n_elements, each one of
//!element_lengths[i]*sizeof_element bytes.
//!Non-throwing version. chain.size() is not increased on failure.
void allocate_many(const std::nothrow_t &tag, const size_type *elem_sizes, size_type n_elements, size_type sizeof_element, multiallocation_chain &chain)
{ mp_header->allocate_many(tag, elem_sizes, n_elements, sizeof_element, chain); }
//!Deallocates all elements contained in chain.
//!Never throws.
void deallocate_many(multiallocation_chain &chain)
{ mp_header->deallocate_many(chain); }
#endif //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED
//!Marks previously allocated memory as free. Never throws.
void deallocate (void *addr)
{ if (mp_header) mp_header->deallocate(addr); }
//!Tries to find a previous named allocation address. Returns a memory
//!buffer and the object count. If not found returned pointer is 0.
//!Never throws.
template <class T>
std::pair<T*, size_type> find (char_ptr_holder_t name)
{ return mp_header->template find<T>(name); }
//!Creates a named object or array in memory
//!
//!Allocates and constructs a T object or an array of T in memory,
//!associates this with the given name and returns a pointer to the
//!created object. If an array is being constructed all objects are
//!created using the same parameters given to this function.
//!
//!-> If the name was previously used, returns 0.
//!
//!-> Throws boost::interprocess::bad_alloc if there is no available memory
//!
//!-> If T's constructor throws, the function throws that exception.
//!
//!Memory is freed automatically if T's constructor throws and if an
//!array was being constructed, destructors of created objects are called
//!before freeing the memory.
template <class T>
typename segment_manager::template construct_proxy<T>::type
construct(char_ptr_holder_t name)
{ return mp_header->template construct<T>(name); }
//!Finds or creates a named object or array in memory
//!
//!Tries to find an object with the given name in memory. If
//!found, returns the pointer to this pointer. If the object is not found,
//!allocates and constructs a T object or an array of T in memory,
//!associates this with the given name and returns a pointer to the
//!created object. If an array is being constructed all objects are
//!created using the same parameters given to this function.
//!
//!-> Throws boost::interprocess::bad_alloc if there is no available memory
//!
//!-> If T's constructor throws, the function throws that exception.
//!
//!Memory is freed automatically if T's constructor throws and if an
//!array was being constructed, destructors of created objects are called
//!before freeing the memory.
template <class T>
typename segment_manager::template construct_proxy<T>::type
find_or_construct(char_ptr_holder_t name)
{ return mp_header->template find_or_construct<T>(name); }
//!Creates a named object or array in memory
//!
//!Allocates and constructs a T object or an array of T in memory,
//!associates this with the given name and returns a pointer to the
//!created object. If an array is being constructed all objects are
//!created using the same parameters given to this function.
//!
//!-> If the name was previously used, returns 0.
//!
//!-> Returns 0 if there is no available memory
//!
//!-> If T's constructor throws, the function throws that exception.
//!
//!Memory is freed automatically if T's constructor throws and if an
//!array was being constructed, destructors of created objects are called
//!before freeing the memory.
template <class T>
typename segment_manager::template construct_proxy<T>::type
construct(char_ptr_holder_t name, const std::nothrow_t &tag)
{ return mp_header->template construct<T>(name, tag); }
//!Finds or creates a named object or array in memory
//!
//!Tries to find an object with the given name in memory. If
//!found, returns the pointer to this pointer. If the object is not found,
//!allocates and constructs a T object or an array of T in memory,
//!associates this with the given name and returns a pointer to the
//!created object. If an array is being constructed all objects are
//!created using the same parameters given to this function.
//!
//!-> Returns 0 if there is no available memory
//!
//!-> If T's constructor throws, the function throws that exception.
//!
//!Memory is freed automatically if T's constructor throws and if an
//!array was being constructed, destructors of created objects are called
//!before freeing the memory.
template <class T>
typename segment_manager::template construct_proxy<T>::type
find_or_construct(char_ptr_holder_t name, const std::nothrow_t &tag)
{ return mp_header->template find_or_construct<T>(name, tag); }
//!Creates a named array from iterators in memory
//!
//!Allocates and constructs an array of T in memory,
//!associates this with the given name and returns a pointer to the
//!created object. Each element in the array is created using the
//!objects returned when dereferencing iterators as parameters
//!and incrementing all iterators for each element.
//!
//!-> If the name was previously used, returns 0.
//!
//!-> Throws boost::interprocess::bad_alloc if there is no available memory
//!
//!-> If T's constructor throws, the function throws that exception.
//!
//!Memory is freed automatically if T's constructor throws and
//!destructors of created objects are called before freeing the memory.
template <class T>
typename segment_manager::template construct_iter_proxy<T>::type
construct_it(char_ptr_holder_t name)
{ return mp_header->template construct_it<T>(name); }
//!Finds or creates a named array from iterators in memory
//!
//!Tries to find an object with the given name in memory. If
//!found, returns the pointer to this pointer. If the object is not found,
//!allocates and constructs an array of T in memory,
//!associates this with the given name and returns a pointer to the
//!created object. Each element in the array is created using the
//!objects returned when dereferencing iterators as parameters
//!and incrementing all iterators for each element.
//!
//!-> If the name was previously used, returns 0.
//!
//!-> Throws boost::interprocess::bad_alloc if there is no available memory
//!
//!-> If T's constructor throws, the function throws that exception.
//!
//!Memory is freed automatically if T's constructor throws and
//!destructors of created objects are called before freeing the memory.
template <class T>
typename segment_manager::template construct_iter_proxy<T>::type
find_or_construct_it(char_ptr_holder_t name)
{ return mp_header->template find_or_construct_it<T>(name); }
//!Creates a named array from iterators in memory
//!
//!Allocates and constructs an array of T in memory,
//!associates this with the given name and returns a pointer to the
//!created object. Each element in the array is created using the
//!objects returned when dereferencing iterators as parameters
//!and incrementing all iterators for each element.
//!
//!-> If the name was previously used, returns 0.
//!
//!-> If there is no available memory, returns 0.
//!
//!-> If T's constructor throws, the function throws that exception.
//!
//!Memory is freed automatically if T's constructor throws and
//!destructors of created objects are called before freeing the memory.*/
template <class T>
typename segment_manager::template construct_iter_proxy<T>::type
construct_it(char_ptr_holder_t name, const std::nothrow_t &tag)
{ return mp_header->template construct_it<T>(name, tag); }
//!Finds or creates a named array from iterators in memory
//!
//!Tries to find an object with the given name in memory. If
//!found, returns the pointer to this pointer. If the object is not found,
//!allocates and constructs an array of T in memory,
//!associates this with the given name and returns a pointer to the
//!created object. Each element in the array is created using the
//!objects returned when dereferencing iterators as parameters
//!and incrementing all iterators for each element.
//!
//!-> If the name was previously used, returns 0.
//!
//!-> If there is no available memory, returns 0.
//!
//!-> If T's constructor throws, the function throws that exception.
//!
//!Memory is freed automatically if T's constructor throws and
//!destructors of created objects are called before freeing the memory.*/
template <class T>
typename segment_manager::template construct_iter_proxy<T>::type
find_or_construct_it(char_ptr_holder_t name, const std::nothrow_t &tag)
{ return mp_header->template find_or_construct_it<T>(name, tag); }
//!Calls a functor and guarantees that no new construction, search or
//!destruction will be executed by any process while executing the object
//!function call. If the functor throws, this function throws.
template <class Func>
void atomic_func(Func &f)
{ mp_header->atomic_func(f); }
//!Tries to call a functor guaranteeing that no new construction, search or
//!destruction will be executed by any process while executing the object
//!function call. If the atomic function can't be immediatelly executed
//!because the internal mutex is already locked, returns false.
//!If the functor throws, this function throws.
template <class Func>
bool try_atomic_func(Func &f)
{ return mp_header->try_atomic_func(f); }
//!Destroys a named memory object or array.
//!
//!Finds the object with the given name, calls its destructors,
//!frees used memory and returns true.
//!
//!-> If the object is not found, it returns false.
//!
//!Exception Handling:
//!
//!When deleting a dynamically object or array, the Standard
//!does not guarantee that dynamically allocated memory, will be released.
//!Also, when deleting arrays, the Standard doesn't require calling
//!destructors for the rest of the objects if for one of them the destructor
//!terminated with an exception.
//!
//!Destroying an object:
//!
//!If the destructor throws, the memory will be freed and that exception
//!will be thrown.
//!
//!Destroying an array:
//!
//!When destroying an array, if a destructor throws, the rest of
//!destructors are called. If any of these throws, the exceptions are
//!ignored. The name association will be erased, memory will be freed and
//!the first exception will be thrown. This guarantees the unlocking of
//!mutexes and other resources.
//!
//!For all theses reasons, classes with throwing destructors are not
//!recommended.
template <class T>
bool destroy(const CharType *name)
{ return mp_header->template destroy<T>(name); }
//!Destroys the unique instance of type T
//!
//!Calls the destructor, frees used memory and returns true.
//!
//!Exception Handling:
//!
//!When deleting a dynamically object, the Standard does not
//!guarantee that dynamically allocated memory will be released.
//!
//!Destroying an object:
//!
//!If the destructor throws, the memory will be freed and that exception
//!will be thrown.
//!
//!For all theses reasons, classes with throwing destructors are not
//!recommended for memory.
template <class T>
bool destroy(const unique_instance_t *const )
{ return mp_header->template destroy<T>(unique_instance); }
//!Destroys the object (named, unique, or anonymous)
//!
//!Calls the destructor, frees used memory and returns true.
//!
//!Exception Handling:
//!
//!When deleting a dynamically object, the Standard does not
//!guarantee that dynamically allocated memory will be released.
//!
//!Destroying an object:
//!
//!If the destructor throws, the memory will be freed and that exception
//!will be thrown.
//!
//!For all theses reasons, classes with throwing destructors are not
//!recommended for memory.
template <class T>
void destroy_ptr(const T *ptr)
{ mp_header->template destroy_ptr<T>(ptr); }
//!Returns the name of an object created with construct/find_or_construct
//!functions. If ptr points to an unique instance typeid(T).name() is returned.
template<class T>
static const char_type *get_instance_name(const T *ptr)
{ return segment_manager::get_instance_name(ptr); }
//!Returns is the type an object created with construct/find_or_construct
//!functions. Does not throw.
template<class T>
static instance_type get_instance_type(const T *ptr)
{ return segment_manager::get_instance_type(ptr); }
//!Returns the length of an object created with construct/find_or_construct
//!functions (1 if is a single element, >=1 if it's an array). Does not throw.
template<class T>
static size_type get_instance_length(const T *ptr)
{ return segment_manager::get_instance_length(ptr); }
//!Preallocates needed index resources to optimize the
//!creation of "num" named objects in the memory segment.
//!Can throw boost::interprocess::bad_alloc if there is no enough memory.
void reserve_named_objects(size_type num)
{ mp_header->reserve_named_objects(num); }
//!Preallocates needed index resources to optimize the
//!creation of "num" unique objects in the memory segment.
//!Can throw boost::interprocess::bad_alloc if there is no enough memory.
void reserve_unique_objects(size_type num)
{ mp_header->reserve_unique_objects(num); }
//!Calls shrink_to_fit in both named and unique object indexes
//to try to free unused memory from those indexes.
void shrink_to_fit_indexes()
{ mp_header->shrink_to_fit_indexes(); }
//!Returns the number of named objects stored
//!in the managed segment.
size_type get_num_named_objects()
{ return mp_header->get_num_named_objects(); }
//!Returns the number of unique objects stored
//!in the managed segment.
size_type get_num_unique_objects()
{ return mp_header->get_num_unique_objects(); }
//!Returns a constant iterator to the index storing the
//!named allocations. NOT thread-safe. Never throws.
const_named_iterator named_begin() const
{ return mp_header->named_begin(); }
//!Returns a constant iterator to the end of the index
//!storing the named allocations. NOT thread-safe. Never throws.
const_named_iterator named_end() const
{ return mp_header->named_end(); }
//!Returns a constant iterator to the index storing the
//!unique allocations. NOT thread-safe. Never throws.
const_unique_iterator unique_begin() const
{ return mp_header->unique_begin(); }
//!Returns a constant iterator to the end of the index
//!storing the unique allocations. NOT thread-safe. Never throws.
const_unique_iterator unique_end() const
{ return mp_header->unique_end(); }
//!This is the default allocator to allocate types T
//!from this managed segment
template<class T>
struct allocator
{
typedef typename segment_manager::template allocator<T>::type type;
};
//!Returns an instance of the default allocator for type T
//!initialized that allocates memory from this segment manager.
template<class T>
typename allocator<T>::type
get_allocator()
{ return mp_header->template get_allocator<T>(); }
//!This is the default deleter to delete types T
//!from this managed segment.
template<class T>
struct deleter
{
typedef typename segment_manager::template deleter<T>::type type;
};
//!Returns an instance of the default allocator for type T
//!initialized that allocates memory from this segment manager.
template<class T>
typename deleter<T>::type
get_deleter()
{ return mp_header->template get_deleter<T>(); }
#if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED)
//!Tries to find a previous named allocation address. Returns a memory
//!buffer and the object count. If not found returned pointer is 0.
//!Never throws.
template <class T>
std::pair<T*, size_type> find_no_lock (char_ptr_holder_t name)
{ return mp_header->template find_no_lock<T>(name); }
#endif //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED
protected:
//!Swaps the segment manager's managed by this managed memory segment.
//!NOT thread-safe. Never throws.
void swap(basic_managed_memory_impl &other)
{ (simple_swap)(mp_header, other.mp_header); }
private:
segment_manager *mp_header;
};
template<class BasicManagedMemoryImpl>
class create_open_func
{
typedef typename BasicManagedMemoryImpl::size_type size_type;
public:
create_open_func(BasicManagedMemoryImpl * const frontend, create_enum_t type)
: m_frontend(frontend), m_type(type){}
bool operator()(void *addr, std::size_t size, bool created) const
{
if( ((m_type == DoOpen) && created) ||
((m_type == DoCreate) && !created) ||
//Check for overflow
size_type(-1) < size ){
return false;
}
else if(created){
return m_frontend->create_impl(addr, static_cast<size_type>(size));
}
else{
return m_frontend->open_impl (addr, static_cast<size_type>(size));
}
}
static std::size_t get_min_size()
{
const size_type sz = BasicManagedMemoryImpl::segment_manager::get_min_size();
if(sz > std::size_t(-1)){
//The minimum size is not representable by std::size_t
BOOST_ASSERT(false);
return std::size_t(-1);
}
else{
return static_cast<std::size_t>(sz);
}
}
private:
BasicManagedMemoryImpl *m_frontend;
create_enum_t m_type;
};
} //namespace ipcdetail {
} //namespace interprocess {
} //namespace boost {
#include <boost/interprocess/detail/config_end.hpp>
#endif //BOOST_INTERPROCESS_DETAIL_MANAGED_MEMORY_IMPL_HPP