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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.
//
//////////////////////////////////////////////////////////////////////////////
#include <boost/interprocess/detail/workaround.hpp>
//[doc_cached_node_allocator
#include <boost/interprocess/managed_shared_memory.hpp>
#include <boost/interprocess/allocators/cached_node_allocator.hpp>
#include <cassert>
//<-
#include "../test/get_process_id_name.hpp"
//->
using namespace boost::interprocess;
int main ()
{
//Remove shared memory on construction and destruction
struct shm_remove
{
shm_remove() { shared_memory_object::remove(test::get_process_id_name()); }
~shm_remove(){ shared_memory_object::remove(test::get_process_id_name()); }
} remover;
//<-
(void)remover;
//->
//Create shared memory
managed_shared_memory segment(create_only, test::get_process_id_name(), 65536);
//Create a cached_node_allocator that allocates ints from the managed segment
//The number of chunks per segment is the default value
typedef cached_node_allocator<int, managed_shared_memory::segment_manager>
cached_node_allocator_t;
cached_node_allocator_t allocator_instance(segment.get_segment_manager());
//The max cached nodes are configurable per instance
allocator_instance.set_max_cached_nodes(3);
//Create another cached_node_allocator. Since the segment manager address
//is the same, this cached_node_allocator will be
//attached to the same pool so "allocator_instance2" can deallocate
//nodes allocated by "allocator_instance"
cached_node_allocator_t allocator_instance2(segment.get_segment_manager());
//The max cached nodes are configurable per instance
allocator_instance2.set_max_cached_nodes(5);
//Create another cached_node_allocator using copy-constructor. This
//cached_node_allocator will also be attached to the same pool
cached_node_allocator_t allocator_instance3(allocator_instance2);
//We can clear the cache
allocator_instance3.deallocate_cache();
//All allocators are equal
assert(allocator_instance == allocator_instance2);
assert(allocator_instance2 == allocator_instance3);
//So memory allocated with one can be deallocated with another
allocator_instance2.deallocate(allocator_instance.allocate(1), 1);
allocator_instance3.deallocate(allocator_instance2.allocate(1), 1);
//The common pool will be destroyed here, since no allocator is
//attached to the pool
return 0;
}
//]
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