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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;
}
//]
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