Re: [Boost-users] Boost serialization: Problem reading strings frombinary archive

From: Robert Ramey (ramey_at_[hidden])
Date: 2007-11-10 11:33:58

try replacing 
    std::ofstream ofs("test.bin"); 
with
    std::ofstream ofs("test.bin", ios::binary); 
does that help?

Robert Ramey
  "Mahesh Venkitachalam" <mkvenkit.vc_at_[hidden]> wrote in message news:6164abb70711100543x284a2592p2189dd14a54d0d54_at_mail.gmail.com...
  Hello, 

  I am having a strange problem with std::string as I am trying to read 
  from a binary archive using Boost serialization. I am new to this, and 
  it is possible that I have not understood the usage. In the code 
  below, the string "faultblock" seems to be causing the problem. The 
  code crashes in the ia & tst line which is reading back the archive - 
  the stack indicates that it is trying to read an invalid string. 

  I have tried to minimize the code I need to post, but sorry if this is 
  still too much. 

  I'd appreciate any help with this. I am using Boost 1.34.0 on windows 
  XP. 

  Best Regards 

  Mahesh 

  // 
  // test.cpp 
  // 
  #include <iomanip> 
  #include <iostream> 
  #include <fstream> 
  #include <string> 
  #include <vector> 
  #include <boost/archive/text_iarchive 
  .hpp> 
  #include <boost/archive/text_oarchive.hpp 
  #include <boost/archive/binary_oarchive.hpp> 
  #include <boost/archive/binary_iarchive.hpp> 
  #include <boost/serialization/base_object.hpp> 
  #include <boost/serialization/utility.hpp> 
  #include <boost/serialization/list.hpp> 

  #include "Attribute4dv.h" 

  using namespace std; 

  class Test 
  { 
  private: 
      friend class boost::serialization::access; 
      template<class Archive> 
      void serialize(Archive & ar, const unsigned int version) 
      { 
      ar.template register_type<AttrDouble4dv>(); 
      ar.template register_type<AttrString4dv>(); 

      ar & _attrs; 
      } 

  public: 

      vector<Attribute4dv*> _attrs; 

      Test() {} 
      ~Test() {} 

  }; 

  int main(int argc, char* arv[]) 
  { 
      // save data to archive 
      { 
      Test* tst = new Test; 
      vector<double> dVals; 
      dVals.push_back(1.1); 
      dVals.push_back(2.2); 
      AttrDouble4dv* attr1 = new AttrDouble4dv; 
      attr1->_name = "attr1"; 
      attr1->_vals = dVals; 
      tst->_attrs.push_back(attr1); 

      vector<string> lut; 
      lut.push_back("2001"); 
      lut.push_back("2002"); 
      vector<int> lutIndices; 
      lutIndices.push_back (0); 
      lutIndices.push_back(1); 
      AttrString4dv* attr2 = new AttrString4dv; 
      attr2->_name = "faultblock"; 
      attr2->_indices = lutIndices; 
      attr2->_lut = lut; 
      tst->_attrs.push_back(attr2); 

      const Test* tst2 = tst; 
      std::ofstream ofs("test.bin"); 
          boost::archive::binary_oarchive oa(ofs); 
          oa & tst2; 
      } 

      // read data from archive 
      { 
      Test* tst; 
      std::ifstream ifs("test.bin", std::ios::binary); 
      boost::archive::binary_iarchive ia(ifs); 
      ia & tst; 
      int j = 0; 
      } 

      return 0; 

  } 

  // 
  // Attribute4dv.h 
  // 
  #ifndef _ATTRIBUTE4DV_H 
  #define _ATTRIBUTE4DV_H 

  #include <vector> 
  #include <boost/archive/text_iarchive.hpp> 
  #include <boost/serialization/base_object.hpp> 
  #include <boost/serialization/string.hpp> 
  #include <boost/serialization/vector.hpp> 

  // Base class 
  class Attribute4dv 
  { 
   public: 

      Attribute4dv() {} 
      virtual ~Attribute4dv() {} 

      // name of attribute 
      std::string _name; 

   private: 

      // for serialization 
      friend class boost::serialization::access; 
      template<class Archive> 
      void serialize(Archive &ar, const unsigned int version) 
      { 
      ar & _name; 
      } 

  }; 

  // double attributes 
  class AttrDouble4dv : public Attribute4dv 
  { 
   public: 

      AttrDouble4dv() {} 
      ~AttrDouble4dv() {} 

      std::vector<double> _vals; 

   private: 

      // for serialization 
      friend class boost::serialization::access; 
      template<class Archive> 
      void serialize(Archive &ar, const unsigned int version) 
      { 
      // save/load base class info 
      ar & boost::serialization::base_object<Attribute4dv>(*this); 

      ar & _vals; 
      } 

  }; 

  // string attributes 
  class AttrString4dv : public Attribute4dv 
  { 
   public: 

      AttrString4dv() {} 
      ~AttrString4dv() {} 

      // a lookup table (LUT) of strings 
      std::vector<std::string> _lut; 
      // indices to the LUT 
      std::vector<int> _indices; 

   private: 

      // for serialization 
      friend class boost::serialization::access; 
      template<class Archive> 
      void serialize(Archive &ar, const unsigned int version) 
      { 
      // save/load base class info 
      ar & boost::serialization::base_object<Attribute4dv>(*this); 

      ar & _lut; 
      ar & _indices; 
      } 

  }; 

  #endif // _ATTRIBUTE4DV_H 

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