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////////////////////////////////////////////////////////////
//
// SFML - Simple and Fast Multimedia Library
// Copyright (C) 2007-2014 Laurent Gomila (laurent.gom@gmail.com)
//
// This software is provided 'as-is', without any express or implied warranty.
// In no event will the authors be held liable for any damages arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it freely,
// subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented;
// you must not claim that you wrote the original software.
// If you use this software in a product, an acknowledgment
// in the product documentation would be appreciated but is not required.
//
// 2. Altered source versions must be plainly marked as such,
// and must not be misrepresented as being the original software.
//
// 3. This notice may not be removed or altered from any source distribution.
//
////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////
// Headers
////////////////////////////////////////////////////////////
#include <SFML/Network/UdpSocket.hpp>
#include <SFML/Network/IpAddress.hpp>
#include <SFML/Network/Packet.hpp>
#include <SFML/Network/SocketImpl.hpp>
#include <SFML/System/Err.hpp>
#include <algorithm>
namespace sf
{
////////////////////////////////////////////////////////////
UdpSocket::UdpSocket() :
Socket (Udp),
m_buffer(MaxDatagramSize)
{
}
////////////////////////////////////////////////////////////
unsigned short UdpSocket::getLocalPort() const
{
if (getHandle() != priv::SocketImpl::invalidSocket())
{
// Retrieve informations about the local end of the socket
sockaddr_in address;
priv::SocketImpl::AddrLength size = sizeof(address);
if (getsockname(getHandle(), reinterpret_cast<sockaddr*>(&address), &size) != -1)
{
return ntohs(address.sin_port);
}
}
// We failed to retrieve the port
return 0;
}
////////////////////////////////////////////////////////////
Socket::Status UdpSocket::bind(unsigned short port)
{
// Create the internal socket if it doesn't exist
create();
// Bind the socket
sockaddr_in address = priv::SocketImpl::createAddress(INADDR_ANY, port);
if (::bind(getHandle(), reinterpret_cast<sockaddr*>(&address), sizeof(address)) == -1)
{
err() << "Failed to bind socket to port " << port << std::endl;
return Error;
}
return Done;
}
////////////////////////////////////////////////////////////
void UdpSocket::unbind()
{
// Simply close the socket
close();
}
////////////////////////////////////////////////////////////
Socket::Status UdpSocket::send(const void* data, std::size_t size, const IpAddress& remoteAddress, unsigned short remotePort)
{
// Create the internal socket if it doesn't exist
create();
// Make sure that all the data will fit in one datagram
if (size > MaxDatagramSize)
{
err() << "Cannot send data over the network "
<< "(the number of bytes to send is greater than sf::UdpSocket::MaxDatagramSize)" << std::endl;
return Error;
}
// Build the target address
sockaddr_in address = priv::SocketImpl::createAddress(remoteAddress.toInteger(), remotePort);
// Send the data (unlike TCP, all the data is always sent in one call)
int sent = sendto(getHandle(), static_cast<const char*>(data), static_cast<int>(size), 0, reinterpret_cast<sockaddr*>(&address), sizeof(address));
// Check for errors
if (sent < 0)
return priv::SocketImpl::getErrorStatus();
return Done;
}
////////////////////////////////////////////////////////////
Socket::Status UdpSocket::receive(void* data, std::size_t size, std::size_t& received, IpAddress& remoteAddress, unsigned short& remotePort)
{
// First clear the variables to fill
received = 0;
remoteAddress = IpAddress();
remotePort = 0;
// Check the destination buffer
if (!data)
{
err() << "Cannot receive data from the network (the destination buffer is invalid)" << std::endl;
return Error;
}
// Data that will be filled with the other computer's address
sockaddr_in address = priv::SocketImpl::createAddress(INADDR_ANY, 0);
// Receive a chunk of bytes
priv::SocketImpl::AddrLength addressSize = sizeof(address);
int sizeReceived = recvfrom(getHandle(), static_cast<char*>(data), static_cast<int>(size), 0, reinterpret_cast<sockaddr*>(&address), &addressSize);
// Check for errors
if (sizeReceived < 0)
return priv::SocketImpl::getErrorStatus();
// Fill the sender informations
received = static_cast<std::size_t>(sizeReceived);
remoteAddress = IpAddress(ntohl(address.sin_addr.s_addr));
remotePort = ntohs(address.sin_port);
return Done;
}
////////////////////////////////////////////////////////////
Socket::Status UdpSocket::send(Packet& packet, const IpAddress& remoteAddress, unsigned short remotePort)
{
// UDP is a datagram-oriented protocol (as opposed to TCP which is a stream protocol).
// Sending one datagram is almost safe: it may be lost but if it's received, then its data
// is guaranteed to be ok. However, splitting a packet into multiple datagrams would be highly
// unreliable, since datagrams may be reordered, dropped or mixed between different sources.
// That's why SFML imposes a limit on packet size so that they can be sent in a single datagram.
// This also removes the overhead associated to packets -- there's no size to send in addition
// to the packet's data.
// Get the data to send from the packet
std::size_t size = 0;
const void* data = packet.onSend(size);
// Send it
return send(data, size, remoteAddress, remotePort);
}
////////////////////////////////////////////////////////////
Socket::Status UdpSocket::receive(Packet& packet, IpAddress& remoteAddress, unsigned short& remotePort)
{
// See the detailed comment in send(Packet) above.
// Receive the datagram
std::size_t received = 0;
Status status = receive(&m_buffer[0], m_buffer.size(), received, remoteAddress, remotePort);
// If we received valid data, we can copy it to the user packet
packet.clear();
if ((status == Done) && (received > 0))
packet.onReceive(&m_buffer[0], received);
return status;
}
} // namespace sf
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