Re: [Boost-users] Boost Shared Memory Compilation Issue

Subject: Re: [Boost-users] Boost Shared Memory Compilation Issue
From: Nathan Lewis (nathanlewissubscription_at_[hidden])
Date: 2011-07-27 04:02:47

TONGARI <tongari95 <at> gmail.com> writes:

> 
> 
I hate to continue this, I've been working with this a bit more and am running
into another compilation issue that is vague to me. I am now trying to put the
object Complex_Data into a vector in shared memory below and it is complaining
about the following:
error C2679: binary '=' : no operator found which takes a right-hand operand of
type 'const complex_data' (or there is no acceptable conversion)
1>        c:\code\test.cpp(113):

Line 133 is the end of the complex data class (closing bracket) It seems that it
is expecting the class to have an assignment operator or copy constructor, I am
not sure. I appreciate any help you might have. I am kind of trying to follow
the container of container example but instead using a vector.

#include <boost/interprocess/managed_shared_memory.hpp>
#include <boost/interprocess/allocators/allocator.hpp>
#include <boost/interprocess/containers/map.hpp>
#include <boost/interprocess/containers/vector.hpp>
#include <boost/interprocess/containers/string.hpp>

using namespace boost::interprocess;
using std::cout;
using std::endl;

//Typedefs of allocators and containers
typedef managed_shared_memory::segment_manager  segment_manager_t;
typedef allocator<void, segment_manager_t>      void_allocator;
typedef allocator<int, segment_manager_t>       int_allocator;
typedef vector<int, int_allocator>              int_vector;
typedef allocator<int_vector, segment_manager_t>int_vector_allocator;
typedef vector<int_vector, int_vector_allocator>int_vector_vector;
typedef allocator<char, segment_manager_t>      char_allocator;
typedef basic_string<char, std::char_traits<char>, char_allocator>   char_string;
typedef allocator<char_string, segment_manager_t> char_string_allocator;
typedef vector<char_string, char_string_allocator>char_string_vector_vector;
typedef char_string_vector_vector::iterator       char_string_vector_iterator;

class complex_data
{
public: //Obviously making the variables of complex_data public isn't a good
idea I am just playing here for the moment
   int                        id_;
   char_string       char_string_;
   char_string_vector_vector char_string_vector_vector_;
   double price_;
   //Since void_allocator is convertible to any other allocator<T>, we simplify
   //the initialization taking just one allocator for all inner containers.
   complex_data(int id, const char *name, double prce, const void_allocator
&void_alloc): id_(id), char_string_(name, void_alloc),
char_string_vector_vector_(void_alloc), price_(prce)
   {}

   void addStringItem(const char* s)
   {
      //Every time you build from a raw string you need an allocator
      //in the constructor
      char_allocator alloc(char_string_vector_vector_.get_allocator());
      char_string_vector_vector_.push_back(char_string(s, alloc));
   }
};

typedef allocator<complex_data, segment_manager_t> ShmemExchangeDataAllocator;
typedef vector<complex_data, ShmemExchangeDataAllocator> ComplexDataVector;

int main ()
{
   //Remove shared memory on construction and destruction
   struct shm_remove
   {
      shm_remove() { shared_memory_object::remove("MySharedMemory"); }
      ~shm_remove(){ shared_memory_object::remove("MySharedMemory"); }
   } remover;

   //Create shared memory
   managed_shared_memory segment(create_only,"MySharedMemory", 65536);

   //An allocator convertible to any allocator<T, segment_manager_t> type
   void_allocator alloc_inst(segment.get_segment_manager());

   ComplexDataVector* myComplexDataVector =
segment.construct<ComplexDataVector>("ComplexDataVector")(alloc_inst);

   complex_data myItem(7, "hi", 7.0, alloc_inst);
   myItem.addStringItem("hello");
   myItem.addStringItem("how");
   myItem.addStringItem("are");
   myItem.addStringItem("you");

   myComplexDataVector->push_back(myItem);

   //
   return 0;
}