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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.

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

#ifdef NDEBUG

#undef NDEBUG

#endif

#include <boost/interprocess/detail/workaround.hpp>

//[doc_bufferstream

#include <boost/interprocess/managed_shared_memory.hpp>

#include <boost/interprocess/streams/bufferstream.hpp>

#include <vector>

#include <iterator>

#include <algorithm> //std::copy, std::equal

#include <cstddef>

//<-

#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);

//Fill data

std::vector<int> data;

data.reserve(100);

for(std::size_t i = 0; i < 100; ++i){

data.push_back((int)i);

}

const std::size_t BufferSize = 100*5;

//Allocate a buffer in shared memory to write data

char *my_cstring =

segment.construct<char>("MyCString")[BufferSize]('\0');

bufferstream mybufstream(my_cstring, BufferSize);

//Now write data to the buffer

for(std::size_t i = 0; i < 100; ++i){

mybufstream << data[i] << std::endl;

}

//Check there was no overflow attempt

assert(mybufstream.good());

//Extract all values from the shared memory string

//directly to a vector.

std::vector<int> data2;

std::istream_iterator<int> it(mybufstream), itend;

std::copy(it, itend, std::back_inserter(data2));

//This extraction should have ended will fail error since

//the numbers formatted in the buffer end before the end

//of the buffer. (Otherwise it would trigger eofbit)

assert(mybufstream.fail());

//Compare data

assert(std::equal(data.begin(), data.end(), data2.begin()));

//Clear errors and rewind

mybufstream.clear();

mybufstream.seekp(0, std::ios::beg);

//Now write again the data trying to do a buffer overflow

for(std::size_t i = 0, m = data.size()*5; i < m; ++i){

mybufstream << data[i%5u] << std::endl;

}

//Now make sure badbit is active

//which means overflow attempt.

assert(!mybufstream.good());

assert(mybufstream.bad());

segment.destroy_ptr(my_cstring);

return 0;

}

//]