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//////////////////////////////////////////////////////////////////////////////

// (C) Copyright Ion Gaztanaga 2006-2012. 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.

//////////////////////////////////////////////////////////////////////////////

//[doc_managed_external_buffer

#include <boost/interprocess/managed_external_buffer.hpp>

#include <boost/interprocess/allocators/allocator.hpp>

#include <boost/container/list.hpp>

#include <cstring>

#include <boost/aligned_storage.hpp>

int main()

{

using namespace boost::interprocess;

//Create the static memory who will store all objects

const int memsize = 65536;

static boost::aligned_storage<memsize>::type static_buffer;

//This managed memory will construct objects associated with

//a wide string in the static buffer

wmanaged_external_buffer objects_in_static_memory

(create_only, &static_buffer, memsize);

//We optimize resources to create 100 named objects in the static buffer

objects_in_static_memory.reserve_named_objects(100);

//Alias an integer node allocator type

//This allocator will allocate memory inside the static buffer

typedef allocator<int, wmanaged_external_buffer::segment_manager>

allocator_t;

//Alias a STL compatible list to be constructed in the static buffer

typedef boost::container::list<int, allocator_t> MyBufferList;

//The list must be initialized with the allocator

//All objects created with objects_in_static_memory will

//be stored in the static_buffer!

MyBufferList *list = objects_in_static_memory.construct<MyBufferList>(L"MyList")

(objects_in_static_memory.get_segment_manager());

//<-

(void)list;

//->

//Since the allocation algorithm from wmanaged_external_buffer uses relative

//pointers and all the pointers constructed int the static memory point

//to objects in the same segment, we can create another static buffer

//from the first one and duplicate all the data.

static boost::aligned_storage<memsize>::type static_buffer2;

std::memcpy(&static_buffer2, &static_buffer, memsize);

//Now open the duplicated managed memory passing the memory as argument

wmanaged_external_buffer objects_in_static_memory2

(open_only, &static_buffer2, memsize);

//Check that "MyList" has been duplicated in the second buffer

if(!objects_in_static_memory2.find<MyBufferList>(L"MyList").first)

return 1;

//Destroy the lists from the static buffers

objects_in_static_memory.destroy<MyBufferList>(L"MyList");

objects_in_static_memory2.destroy<MyBufferList>(L"MyList");

return 0;

}

//]