ex12_15.cpp

//
//  ex12_15.cpp
//  Exercise 12.15
//
//  Created by pezy on 12/22/14.
//  Copyright (c) 2014 pezy. All rights reserved.
//
//  Rewrite the first exercise to use a lambda (10.3.2, p.388) in place of the
//  end_connection function.

#include <iostream>
#include <string>
#include <memory>

struct connection {
    std::string ip;
    int port;
    connection(std::string ip_, int port_) : ip(ip_), port(port_) {}
};
struct destination {
    std::string ip;
    int port;
    destination(std::string ip_, int port_) : ip(ip_), port(port_) {}
};

connection connect(destination* pDest)
{
    std::shared_ptr<connection> pConn(new connection(pDest->ip, pDest->port));
    std::cout << "creating connection(" << pConn.use_count() << ")"
              << std::endl;
    return *pConn;
}

void disconnect(connection pConn)
{
    std::cout << "connection close(" << pConn.ip << ":" << pConn.port << ")"
              << std::endl;
}

void f(destination& d)
{
    connection conn = connect(&d);
    std::shared_ptr<connection> p(&conn, [](connection* p) { disconnect(*p); });
    std::cout << "connecting now(" << p.use_count() << ")" << std::endl;
}

int main()
{
    destination dest("202.118.176.67", 3316);
    f(dest);
}