OpenRCT2/src/network/NetworkConnection.cpp

#pragma region Copyright (c) 2014-2016 OpenRCT2 Developers
/*****************************************************************************
 * OpenRCT2, an open source clone of Roller Coaster Tycoon 2.
 *
 * OpenRCT2 is the work of many authors, a full list can be found in contributors.md
 * For more information, visit https://github.com/OpenRCT2/OpenRCT2
 *
 * OpenRCT2 is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * A full copy of the GNU General Public License can be found in licence.txt
 *****************************************************************************/
#pragma endregion

#ifndef DISABLE_NETWORK

#include "network.h"
#include "NetworkConnection.h"
#include "../core/String.hpp"
#include <SDL.h>

extern "C"
{
    #include "../localisation/localisation.h"
}

constexpr size_t NETWORK_DISCONNECT_REASON_BUFFER_SIZE = 256;

NetworkConnection::NetworkConnection()
{
    ResetLastPacketTime();
}

NetworkConnection::~NetworkConnection()
{
    delete Socket;
    if (_lastDisconnectReason)
    {
        delete[] _lastDisconnectReason;
    }
}

int NetworkConnection::ReadPacket()
{
    if (InboundPacket.transferred < sizeof(InboundPacket.size))
    {
        // read packet size
        void * buffer = &((char*)&InboundPacket.size)[InboundPacket.transferred];
        size_t bufferLength = sizeof(InboundPacket.size) - InboundPacket.transferred;
        size_t readBytes;
        NETWORK_READPACKET status = Socket->ReceiveData(buffer, bufferLength, &readBytes);
        if (status != NETWORK_READPACKET_SUCCESS)
        {
            return status;
        }
        
        InboundPacket.transferred += readBytes;
        if (InboundPacket.transferred == sizeof(InboundPacket.size))
        {
            InboundPacket.size = Convert::NetworkToHost(InboundPacket.size);
            if (InboundPacket.size == 0) // Can't have a size 0 packet
            {
                return NETWORK_READPACKET_DISCONNECTED;
            }
            InboundPacket.data->resize(InboundPacket.size);
        }
    }
    else
    {
        // read packet data
        if (InboundPacket.data->capacity() > 0)
        {
            void * buffer = &InboundPacket.GetData()[InboundPacket.transferred - sizeof(InboundPacket.size)];
            size_t bufferLength = sizeof(InboundPacket.size) + InboundPacket.size - InboundPacket.transferred;
            size_t readBytes;
            NETWORK_READPACKET status = Socket->ReceiveData(buffer, bufferLength, &readBytes);
            if (status != NETWORK_READPACKET_SUCCESS)
            {
                return status;
            }

            InboundPacket.transferred += readBytes;
        }
        if (InboundPacket.transferred == sizeof(InboundPacket.size) + InboundPacket.size)
        {
            _lastPacketTime = SDL_GetTicks();
            return NETWORK_READPACKET_SUCCESS;
        }
    }
    return NETWORK_READPACKET_MORE_DATA;
}

bool NetworkConnection::SendPacket(NetworkPacket& packet)
{
    uint16 sizen = Convert::HostToNetwork(packet.size);
    std::vector<uint8> tosend;
    tosend.reserve(sizeof(sizen) + packet.size);
    tosend.insert(tosend.end(), (uint8*)&sizen, (uint8*)&sizen + sizeof(sizen));
    tosend.insert(tosend.end(), packet.data->begin(), packet.data->end());

    const void * buffer = &tosend[packet.transferred];
    size_t bufferSize = tosend.size() - packet.transferred;
    size_t sent = Socket->SendData(buffer, bufferSize);
    if (sent > 0)
    {
        packet.transferred += sent;
    }
    if (packet.transferred == tosend.size())
    {
        return true;
    }
    return false;
}

void NetworkConnection::QueuePacket(std::unique_ptr<NetworkPacket> packet, bool front)
{
    if (AuthStatus == NETWORK_AUTH_OK || !packet->CommandRequiresAuth())
    {
        packet->size = (uint16)packet->data->size();
        if (front)
        {
            // If the first packet was already partially sent add new packet to second position
            if (_outboundPackets.size() > 0 && _outboundPackets.front()->transferred > 0)
            {
                auto it = _outboundPackets.begin();
                it++; // Second position
                _outboundPackets.insert(it, std::move(packet));
            }
            else
            {
                _outboundPackets.push_front(std::move(packet));
            }
        }
        else
        {
            _outboundPackets.push_back(std::move(packet));
        }
    }
}

void NetworkConnection::SendQueuedPackets()
{
    while (_outboundPackets.size() > 0 && SendPacket(*(_outboundPackets.front()).get()))
    {
        _outboundPackets.remove(_outboundPackets.front());
    }
}

void NetworkConnection::ResetLastPacketTime()
{
    _lastPacketTime = SDL_GetTicks();
}

bool NetworkConnection::ReceivedPacketRecently()
{
#ifndef DEBUG
    if (SDL_TICKS_PASSED(SDL_GetTicks(), _lastPacketTime + 7000))
    {
        return false;
    }
#endif
    return true;
}

const utf8 * NetworkConnection::GetLastDisconnectReason() const
{
    return this->_lastDisconnectReason;
}

void NetworkConnection::SetLastDisconnectReason(const utf8 * src)
{
    if (src == nullptr)
    {
        if (_lastDisconnectReason)
        {
            delete[] _lastDisconnectReason;
            _lastDisconnectReason = nullptr;
        }
        return;
    }

    if (_lastDisconnectReason == nullptr)
    {
        _lastDisconnectReason = new utf8[NETWORK_DISCONNECT_REASON_BUFFER_SIZE];
    }
    String::Set(_lastDisconnectReason, NETWORK_DISCONNECT_REASON_BUFFER_SIZE, src);
}

void NetworkConnection::SetLastDisconnectReason(const rct_string_id string_id, void *args)
{
    char buffer[NETWORK_DISCONNECT_REASON_BUFFER_SIZE];
    format_string(buffer, string_id, args);
    SetLastDisconnectReason(buffer);
}

#endif