boost serialization std::unique_ptr support
I'm not sure how to interpret this list, but it seems like support for this was added sometime after 1.48. I am using 1.58 and it is included. Just
#include <boost/serialization/unique_ptr.hpp>
and then it will work as follows:
#include <memory>
#include <boost/archive/text_oarchive.hpp>
#include <boost/archive/text_iarchive.hpp>
#include <boost/serialization/unique_ptr.hpp>
#include <fstream>
class Point
{
public:
Point() { }
float x = 1.;
float y = 2.;
float z = 3.;
private:
friend class boost::serialization::access;
template<class TArchive>
void serialize(TArchive & archive, const unsigned int version)
{
archive & x;
archive & y;
archive & z;
}
};
void ValidUniquePointer()
{
std::unique_ptr<Point> p(new Point());
std::ofstream outputStream("test.txt");
boost::archive::text_oarchive outputArchive(outputStream);
outputArchive << p;
outputStream.close();
// read from a text archive
std::unique_ptr<Point> pointRead;
std::ifstream inputStream("test.txt");
boost::archive::text_iarchive inputArchive(inputStream);
inputArchive >> pointRead;
std::cout << pointRead->x << " " << pointRead->y << " " << pointRead->z << std::endl;
}
void NullUniquePointer()
{
std::unique_ptr<Point> p;
std::ofstream outputStream("test.txt");
boost::archive::text_oarchive outputArchive(outputStream);
outputArchive << p;
outputStream.close();
// read from a text archive
std::unique_ptr<Point> pointRead;
std::ifstream inputStream("test.txt");
boost::archive::text_iarchive inputArchive(inputStream);
inputArchive >> pointRead;
if(pointRead != nullptr) {
std::cout << pointRead->x << " " << pointRead->y << " " << pointRead->z << std::endl;
}
else {
std::cout << "Pointer is null!" << std::endl;
}
}
int main()
{
ValidUniquePointer();
NullUniquePointer();
return 0;
}
as mentioned by pmr, I managed to come up the following solution, and at the first glance, everything works. In hope that someone could find it useful:
#include <iostream>
#include <memory>
#include <fstream>
#include <boost/archive/text_oarchive.hpp>
#include <boost/archive/text_iarchive.hpp>
namespace boost {
namespace serialization {
template<class Archive, class T>
inline void save(
Archive & ar,
const std::unique_ptr< T > &t,
const unsigned int /*file_version*/
){
// only the raw pointer has to be saved
const T * const base_pointer = t.get();
ar & BOOST_SERIALIZATION_NVP(base_pointer);
}
template<class Archive, class T>
inline void load(
Archive & ar,
std::unique_ptr< T > &t,
const unsigned int /*file_version*/
){
T *base_pointer;
ar & BOOST_SERIALIZATION_NVP(base_pointer);
t.reset(base_pointer);
}
template<class Archive, class T>
inline void serialize(
Archive & ar,
std::unique_ptr< T > &t,
const unsigned int file_version
){
boost::serialization::split_free(ar, t, file_version);
}
} // namespace serialization
} // namespace boost
class MyDegrees
{
public:
void setDeg(int d){deg = d;}
int getDeg()const {return deg;}
private:
friend class boost::serialization::access;
template<class Archive>
void serialize(Archive & ar, const unsigned int version)
{ ar & deg; }
int deg;
};
class gps_position
{
private:
friend class boost::serialization::access;
template<class Archive>
void serialize(Archive & ar, const unsigned int version)
{ ar & degrees; }
std::unique_ptr<MyDegrees> degrees;
public:
gps_position(): degrees(std::unique_ptr<MyDegrees>(new MyDegrees)){};
void setDeg(int d){degrees->setDeg(d);}
int getDeg() const {return degrees->getDeg();}
};
int main()
{
std::ofstream ofs("filename");
gps_position g;
g.setDeg(45);
std::cout<<g.getDeg()<<std::endl;
{ boost::archive::text_oarchive oa(ofs); oa << g; }
gps_position newg;
{
std::ifstream ifs("filename");
boost::archive::text_iarchive ia(ifs);
ia >> newg;
std::cout<<newg.getDeg()<<std::endl;
}
return 0;
}
recent versions of boost serialization provide support for all std smart pointer types.