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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/os_file_functions.hpp>
//[doc_managed_copy_on_write
#include <boost/interprocess/managed_mapped_file.hpp>
#include <fstream> //std::fstream
#include <iterator>//std::distance
//<-
#include "../test/get_process_id_name.hpp"
//->
int main()
{
using namespace boost::interprocess;
//Define file names
//<-
#if 1
const char *ManagedFile = 0;
const char *ManagedFile2 = 0;
std::string managed_file_name(boost::interprocess::ipcdetail::get_temporary_path());
managed_file_name += "/"; managed_file_name += test::get_process_id_name();
ManagedFile = managed_file_name.c_str();
std::string managed_file2_name(boost::interprocess::ipcdetail::get_temporary_path());
managed_file2_name += "/"; managed_file2_name += test::get_process_id_name(); managed_file2_name += "_2";
ManagedFile2 = managed_file2_name.c_str();
#else
//->
const char *ManagedFile = "MyManagedFile";
const char *ManagedFile2 = "MyManagedFile2";
//<-
#endif
//->
//Try to erase any previous managed segment with the same name
file_mapping::remove(ManagedFile);
file_mapping::remove(ManagedFile2);
remove_file_on_destroy destroyer1(ManagedFile);
remove_file_on_destroy destroyer2(ManagedFile2);
{
//Create an named integer in a managed mapped file
managed_mapped_file managed_file(create_only, ManagedFile, 65536);
managed_file.construct<int>("MyInt")(0);
//Now create a copy on write version
managed_mapped_file managed_file_cow(open_copy_on_write, ManagedFile);
//Erase the int and create a new one
if(!managed_file_cow.destroy<int>("MyInt"))
throw int(0);
managed_file_cow.construct<int>("MyInt2");
//Check changes
if(managed_file_cow.find<int>("MyInt").first && !managed_file_cow.find<int>("MyInt2").first)
throw int(0);
//Check the original is intact
if(!managed_file.find<int>("MyInt").first && managed_file.find<int>("MyInt2").first)
throw int(0);
{ //Dump the modified copy on write segment to a file
std::fstream file(ManagedFile2, std::ios_base::out | std::ios_base::binary);
if(!file)
throw int(0);
file.write(static_cast<const char *>(managed_file_cow.get_address()), (std::streamsize)managed_file_cow.get_size());
}
//Now open the modified file and test changes
managed_mapped_file managed_file_cow2(open_only, ManagedFile2);
if(managed_file_cow2.find<int>("MyInt").first && !managed_file_cow2.find<int>("MyInt2").first)
throw int(0);
}
{
//Now create a read-only version
managed_mapped_file managed_file_ro(open_read_only, ManagedFile);
//Check the original is intact
if(!managed_file_ro.find<int>("MyInt").first && managed_file_ro.find<int>("MyInt2").first)
throw int(0);
//Check the number of named objects using the iterators
if(std::distance(managed_file_ro.named_begin(), managed_file_ro.named_end()) != 1 &&
std::distance(managed_file_ro.unique_begin(), managed_file_ro.unique_end()) != 0 )
throw int(0);
}
return 0;
}
//]
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