1 //////////////////////////////////////////////////////////////////////////////
2 //
3 // (C) Copyright Ion Gaztanaga 2006-2012. Distributed under the Boost
4 // Software License, Version 1.0. (See accompanying file
5 // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
6 //
7 // See http://www.boost.org/libs/interprocess for documentation.
8 //
9 //////////////////////////////////////////////////////////////////////////////
10 #include <boost/interprocess/detail/config_begin.hpp>
11 //[doc_managed_external_buffer
12 #include <boost/interprocess/managed_external_buffer.hpp>
13 #include <boost/interprocess/allocators/allocator.hpp>
14 #include <boost/interprocess/containers/list.hpp>
15 #include <cstring>
16 #include <boost/aligned_storage.hpp>
17
main()18 int main()
19 {
20 using namespace boost::interprocess;
21
22 //Create the static memory who will store all objects
23 const int memsize = 65536;
24
25 static boost::aligned_storage<memsize>::type static_buffer;
26
27 //This managed memory will construct objects associated with
28 //a wide string in the static buffer
29 wmanaged_external_buffer objects_in_static_memory
30 (create_only, &static_buffer, memsize);
31
32 //We optimize resources to create 100 named objects in the static buffer
33 objects_in_static_memory.reserve_named_objects(100);
34
35 //Alias an integer node allocator type
36 //This allocator will allocate memory inside the static buffer
37 typedef allocator<int, wmanaged_external_buffer::segment_manager>
38 allocator_t;
39
40 //Alias a STL compatible list to be constructed in the static buffer
41 typedef list<int, allocator_t> MyBufferList;
42
43 //The list must be initialized with the allocator
44 //All objects created with objects_in_static_memory will
45 //be stored in the static_buffer!
46 MyBufferList *list = objects_in_static_memory.construct<MyBufferList>(L"MyList")
47 (objects_in_static_memory.get_segment_manager());
48 //<-
49 (void)list;
50 //->
51 //Since the allocation algorithm from wmanaged_external_buffer uses relative
52 //pointers and all the pointers constructed int the static memory point
53 //to objects in the same segment, we can create another static buffer
54 //from the first one and duplicate all the data.
55 static boost::aligned_storage<memsize>::type static_buffer2;
56 std::memcpy(&static_buffer2, &static_buffer, memsize);
57
58 //Now open the duplicated managed memory passing the memory as argument
59 wmanaged_external_buffer objects_in_static_memory2
60 (open_only, &static_buffer2, memsize);
61
62 //Check that "MyList" has been duplicated in the second buffer
63 if(!objects_in_static_memory2.find<MyBufferList>(L"MyList").first)
64 return 1;
65
66 //Destroy the lists from the static buffers
67 objects_in_static_memory.destroy<MyBufferList>(L"MyList");
68 objects_in_static_memory2.destroy<MyBufferList>(L"MyList");
69 return 0;
70 }
71 //]
72 #include <boost/interprocess/detail/config_end.hpp>
73