nat-helper.cpp

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#include <iostream>
#include <functional>
#include "nat-helper.hpp"
 
NatHelper::NatHelper(int port) : port(port),
        io_service(),
        //work_guard(io_service.get_executor()),
        acceptor(io_service),
        pendingSocket(io_service)
{
 
}
 
NatHelper::NatHelper() : NatHelper(12558)
{
 
}
 
 
void NatHelper::worker(){
        std::cout << "Running" << std::endl;
        io_service.run();
        std::cout << "End" << std::endl;
}
 
void NatHelper::run(bool async){
        using namespace std::placeholders;
 
        asio::ip::tcp::endpoint endpoint(asio::ip::tcp::v4(), port);
        acceptor.open(endpoint.protocol());
        acceptor.bind(endpoint);
        acceptor.listen(asio::socket_base::max_connections);
        acceptor.set_option(asio::ip::tcp::acceptor::reuse_address(false));
        acceptor.async_accept(pendingSocket,
                        std::bind(&NatHelper::onConnectionAccepted, this, _1));
 
        if(async){
                std::cout << "Starting thread" << std::endl;
                worker_thread = std::thread(&NatHelper::worker, this);
        } else {
                worker();
        }
}
 
void NatHelper::stop(){
        std::cout << "Stopping..." << std::endl;
        io_service.stop();
        worker_thread.join();
}
 
void NatHelper::onConnectionAccepted(const std::error_code& ec){
        if(ec){
                std::cerr << "Error accepting client connection: " << ec.message() << std::endl;
                return;
        }
 
        using namespace std::placeholders;
 
        auto client = std::make_shared<Client>(std::move(pendingSocket));
        client->readDescription(
                        std::bind(&NatHelper::onClientDesc, this, _1, _2));
        incomingClients.insert({client.get(), std::move(client)});
 
        acceptor.async_accept(pendingSocket,
                        std::bind(&NatHelper::onConnectionAccepted, this, _1));
}
 
void NatHelper::cleanEmptyRooms(){
        for(auto it = rooms.begin(); it != rooms.end(); ){
                if(it->second->isEmpty()){
                        std::cout << "Removing empty room " << it->first << "\n";
                        it = rooms.erase(it);
                } else {
                        it++;
                }
        }
}
 
void NatHelper::onClientDesc(Client& client, CompletionStatus status){
        if(status != CompletionStatus::Success){
                std::cerr << "Error reading client description" << std::endl;
                incomingClients.erase(&client);
                return;
        }
 
        const auto& roomName = client.getRoomName();
        std::cout << "Moving client " << client.getClientName()
                << " to room " << roomName
                << std::endl;
 
        auto roomIt = rooms.find(roomName);
        if(roomIt == rooms.end()){
                cleanEmptyRooms();
                std::cout << "Creating room " << roomName << std::endl;
                roomIt = rooms.insert({roomName, std::make_shared<Room>(roomName)}).first;
        }
 
        auto clientIt = incomingClients.find(&client);
        auto& room = roomIt->second;
        if(room->isFull()){
                std::cerr << "Room " << roomName << " is full, dropping client" << std::endl;
        } else {
                roomIt->second->addClient(std::move(clientIt->second));
        }
        incomingClients.erase(clientIt);
}