[Boost-users] [Q] help serializing a multiset of shared ptrs

Subject: [Boost-users] [Q] help serializing a multiset of shared ptrs
From: V S P (toreason_at_[hidden])
Date: 2009-06-15 00:57:39

Hello,

I am sure I am not doing things quite right in serializing my
multiset, however I could not 'connect the dots' in the serialize
documentation between serializing shared pointers and containers.

Therefore, asking for help.

I created a complete compilable example, that I am attaching below
and the created output file.  The program crashes on the last line
when I am trying to load the data back in.

Any help is greatly appreciated,
Vlad
-------------- prog start ----------------
#include <iostream>
#include <fstream>
#include <ostream>
#include <ctime>
#include <cstdlib>

#include <set>
#include <algorithm>

#include <boost/archive/tmpdir.hpp>
#include <boost/archive/text_iarchive.hpp>
#include <boost/archive/text_oarchive.hpp>
#include <boost/serialization/base_object.hpp>
#include <boost/serialization/utility.hpp>
#include <boost/serialization/list.hpp>
#include <boost/serialization/assume_abstract.hpp>
#include <boost/serialization/base_object.hpp>
#include <boost/serialization/nvp.hpp>

#include <boost/archive/tmpdir.hpp>
#include <boost/archive/xml_oarchive.hpp>
#include <boost/archive/xml_iarchive.hpp>

#include <boost/lexical_cast.hpp>

using namespace std;
using namespace boost;

template <typename TRow, typename TContainer=std::multiset<
shared_ptr<TRow> > >
struct cactivetable_t: public TContainer,
                        private boost::noncopyable

{
  template <typename Archive>
    void
  serialize (Archive& ar, const unsigned int version)
  {
    

    for (TContainer::const_iterator it=begin();
          it!=end();it++)
    {
      (*it)->myserialize(ar,version);      
    }
  }

};

struct tRow
{
  int a;
  string b;

  template <typename Archive>
    void
  myserialize (Archive& ar, const unsigned int version)
  {
    ar&boost::serialization::make_nvp("a", a);
    ar&boost::serialization::make_nvp("b", b);
  }

};

struct randrow
    {
      shared_ptr<tRow> operator()(void)
      {
        shared_ptr<tRow> p(new tRow);
        p->a=rand()%100;
        p->b=lexical_cast<string>(p->a);
        return p;
      }

    };

void main (void)
{
    cactivetable_t<tRow> mytb;
    shared_ptr<tRow> tmpP(new tRow);

    for (size_t i=0;i<10;i++)
    {
      /*note for multiset we can 
      insert the same thing many times */
      mytb.insert(tmpP);
    }

    
    randrow rw;        
    generate(mytb.begin(),mytb.end(),rw);

        // make an archive
    {
      ofstream ofs("xyz.sxml");
      assert(ofs.good());
      boost::archive::xml_oarchive oa(ofs);    
      oa<<BOOST_SERIALIZATION_NVP(mytb);
    }//scope to close file

    cout<<"finished serializing, now lets try to read back"<<endl;
    mytb.clear();

    {
    // open the archive
      std::ifstream ifs("xyz.sxml");
      assert(ifs.good());
      boost::archive::xml_iarchive ia(ifs);

    // restore the schedule from the archive
      ia >> BOOST_SERIALIZATION_NVP(mytb);
    }

    cout<<"after restore tb size is: "<<mytb.size()<<endl;

}

-------------- prog end -------------------

-- archive xyz.sxml XML start ----

<?xml version="1.0" encoding="UTF-8" standalone="yes" ?>
<!DOCTYPE boost_serialization>
<boost_serialization signature="serialization::archive" version="5">
<mytb class_id="0" tracking_level="0" version="0">
        <a>41</a>
        <b>41</b>
        <a>67</a>
        <b>67</b>
        <a>34</a>
        <b>34</b>
        <a>0</a>
        <b>0</b>
        <a>69</a>
        <b>69</b>
        <a>24</a>
        <b>24</b>
        <a>78</a>
        <b>78</b>
        <a>58</a>
        <b>58</b>
        <a>62</a>
        <b>62</b>
        <a>64</a>
        <b>64</b>
</mytb>
</boost_serialization>

--- archive XML end ----
-- 
  V S P
  toreason_at_[hidden]
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