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

Subject: Re: [Boost-users] Boost Shared Memory Compilation Issue
From: Nathan Lewis (nathantoddlewis_at_[hidden])
Date: 2011-07-21 00:28:49

Thank you for your response. I made the changes and it compiles but now I now notice that the string is not in the vector. It seems that it is somehow allocating outside of the shared memory segment. I don't know if this is an issue since it is using a void allocator. I notice that the size of the vector appears to be correct.

Do you have any thoughts on this?  Your input is appreciated.

Below is the updated code:

#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)
   {}

   // add a string --> Error is on the next line
   //void addStringItem(char_string* s){char_string_vector_vector_.push_back(*s);}

   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(someString/*char_string(s, alloc)*/);
   }
};

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());

   char_string tempStr("whatever", alloc_inst);

   cout << "tempStr = " << tempStr << endl;

   //Construct the shared memory map and fill it
   complex_data *mymap = segment.construct<complex_data>("Complex_Data")(7, "hi", 7.0, alloc_inst);
   mymap->addStringItem("hello");

   cout << "Size of char_string_vector_vector = " << mymap->char_string_vector_vector_.size();

   char_string_vector_iterator it = mymap->char_string_vector_vector_.begin();
   while (it != mymap->char_string_vector_vector_.end())
   {
      cout << "Inserted String is: " << endl;
      //cout << "Inserted String is: " << it << endl;
   }
   //cout << "

   //
   return 0;
}

On 7/20/2011 4:34 PM, Ion Gaztañaga wrote:
> El 20/07/2011 1:55, Nathan Lewis escribió:
>> typedef vector<char_string, char_allocator>
>> char_string_vector_vector;
> 
> ERROR: you must define a vector with a char_string_allocator, not a 
> char_allocator, since you are storing char_string. Attached a working 
> exmple and differences
> 
> Best,
> 
> ion
> 
> 
> 
> _______________________________________________
> Boost-users mailing list
> Boost-users_at_[hidden]
> http://lists.boost.org/mailman/listinfo.cgi/boost-users