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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.
//
//////////////////////////////////////////////////////////////////////////////
#if defined(BOOST_INTERPROCESS_MAPPED_FILES)
//[doc_managed_multiple_allocation
#include <boost/interprocess/managed_shared_memory.hpp>
#include <boost/move/utility_core.hpp> //boost::move
#include <cassert>//assert
#include <cstring>//std::memset
#include <new> //std::nothrow
#include <vector> //std::vector
//<-
#include "../test/get_process_id_name.hpp"
//->
int main()
{
using namespace boost::interprocess;
typedef managed_shared_memory::multiallocation_chain multiallocation_chain;
//Remove shared memory on construction and destruction
struct shm_remove
{
//<-
#if 1
shm_remove() { shared_memory_object::remove(test::get_process_id_name()); }
~shm_remove(){ shared_memory_object::remove(test::get_process_id_name()); }
#else
//->
shm_remove() { shared_memory_object::remove("MySharedMemory"); }
~shm_remove(){ shared_memory_object::remove("MySharedMemory"); }
//<-
#endif
//->
} remover;
//<-
(void)remover;
//->
//<-
#if 1
managed_shared_memory managed_shm(create_only,test::get_process_id_name(), 65536);
#else
//->
managed_shared_memory managed_shm(create_only,"MySharedMemory", 65536);
//<-
#endif
//->
//Allocate 16 elements of 100 bytes in a single call. Non-throwing version.
multiallocation_chain chain;
managed_shm.allocate_many(std::nothrow, 100, 16, chain);
//Check if the memory allocation was successful
if(chain.empty()) return 1;
//Allocated buffers
std::vector<void*> allocated_buffers;
//Initialize our data
while(!chain.empty()){
void *buf = chain.pop_front();
allocated_buffers.push_back(buf);
//The iterator must be incremented before overwriting memory
//because otherwise, the iterator is invalidated.
std::memset(buf, 0, 100);
}
//Now deallocate
while(!allocated_buffers.empty()){
managed_shm.deallocate(allocated_buffers.back());
allocated_buffers.pop_back();
}
//Allocate 10 buffers of different sizes in a single call. Throwing version
managed_shared_memory::size_type sizes[10];
for(std::size_t i = 0; i < 10; ++i)
sizes[i] = i*3;
managed_shm.allocate_many(sizes, 10, 1, chain);
managed_shm.deallocate_many(chain);
return 0;
}
//]
#else //#if defined(BOOST_INTERPROCESS_MAPPED_FILES)
int main()
{
return 0;
}
#endif//#if defined(BOOST_INTERPROCESS_MAPPED_FILES)
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