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////////////////////////////////////////////////////////////
//
// SFML - Simple and Fast Multimedia Library
// Copyright (C) 2007-2009 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/SocketUDP.hpp>
#include <SFML/Network/IPAddress.hpp>
#include <SFML/Network/Packet.hpp>
#include <algorithm>
#include <iostream>
#include <string.h>
namespace sf
{
////////////////////////////////////////////////////////////
/// Default constructor
////////////////////////////////////////////////////////////
SocketUDP::SocketUDP()
{
Create();
}
////////////////////////////////////////////////////////////
/// Change the blocking state of the socket
////////////////////////////////////////////////////////////
void SocketUDP::SetBlocking(bool Blocking)
{
// Make sure our socket is valid
if (!IsValid())
Create();
SocketHelper::SetBlocking(mySocket, Blocking);
myIsBlocking = Blocking;
}
////////////////////////////////////////////////////////////
/// Bind the socket to a specific port
////////////////////////////////////////////////////////////
bool SocketUDP::Bind(unsigned short Port)
{
// Check if the socket is already bound to the specified port
if (myPort != Port)
{
// If the socket was previously bound to another port, we need to unbind it first
Unbind();
if (Port != 0)
{
// Build an address with the specified port
sockaddr_in Addr;
Addr.sin_family = AF_INET;
Addr.sin_port = htons(Port);
Addr.sin_addr.s_addr = INADDR_ANY;
memset(Addr.sin_zero, 0, sizeof(Addr.sin_zero));
// Bind the socket to the port
if (bind(mySocket, reinterpret_cast<sockaddr*>(&Addr), sizeof(Addr)) == -1)
{
std::cerr << "Failed to bind the socket to port " << Port << std::endl;
myPort = 0;
return false;
}
}
// Save the new port
myPort = Port;
}
return true;
}
////////////////////////////////////////////////////////////
/// Unbind the socket to its previous port
////////////////////////////////////////////////////////////
bool SocketUDP::Unbind()
{
// To unbind the socket, we just recreate it
if (myPort != 0)
{
Close();
Create();
myPort = 0;
}
return true;
}
////////////////////////////////////////////////////////////
/// Send an array of bytes
////////////////////////////////////////////////////////////
Socket::Status SocketUDP::Send(const char* Data, std::size_t Size, const IPAddress& Address, unsigned short Port)
{
// Make sure the socket is valid
if (!IsValid())
Create();
// Check parameters
if (Data && Size)
{
// Build the target address
sockaddr_in Target;
Target.sin_family = AF_INET;
Target.sin_port = htons(Port);
Target.sin_addr.s_addr = inet_addr(Address.ToString().c_str());
memset(Target.sin_zero, 0, sizeof(Target.sin_zero));
// Loop until every byte has been sent
int Sent = 0;
int SizeToSend = static_cast<int>(Size);
for (int Length = 0; Length < SizeToSend; Length += Sent)
{
// Send a chunk of data
Sent = sendto(mySocket, Data + Length, SizeToSend - Length, 0, reinterpret_cast<sockaddr*>(&Target), sizeof(Target));
// Check errors
if (Sent <= 0)
return SocketHelper::GetErrorStatus();
}
return Socket::Done;
}
else
{
// Error...
std::cerr << "Cannot send data over the network (invalid parameters)" << std::endl;
return Socket::Error;
}
}
////////////////////////////////////////////////////////////
/// Receive an array of bytes.
/// This function will block if the socket is blocking
////////////////////////////////////////////////////////////
Socket::Status SocketUDP::Receive(char* Data, std::size_t MaxSize, std::size_t& SizeReceived, IPAddress& Address, unsigned short& Port)
{
// First clear the size received
SizeReceived = 0;
// Make sure the socket is bound to a port
if (myPort == 0)
{
std::cerr << "Failed to receive data ; the UDP socket first needs to be bound to a port" << std::endl;
return Socket::Error;
}
// Make sure the socket is valid
if (!IsValid())
Create();
// Check parameters
if (Data && MaxSize)
{
// Data that will be filled with the other computer's address
sockaddr_in Sender;
Sender.sin_family = AF_INET;
Sender.sin_port = 0;
Sender.sin_addr.s_addr = INADDR_ANY;
memset(Sender.sin_zero, 0, sizeof(Sender.sin_zero));
SocketHelper::LengthType SenderSize = sizeof(Sender);
// Receive a chunk of bytes
int Received = recvfrom(mySocket, Data, static_cast<int>(MaxSize), 0, reinterpret_cast<sockaddr*>(&Sender), &SenderSize);
// Check the number of bytes received
if (Received > 0)
{
Address = IPAddress(inet_ntoa(Sender.sin_addr));
Port = ntohs(Sender.sin_port);
SizeReceived = static_cast<std::size_t>(Received);
return Socket::Done;
}
else
{
Address = IPAddress();
Port = 0;
return Received == 0 ? Socket::Disconnected : SocketHelper::GetErrorStatus();
}
}
else
{
// Error...
std::cerr << "Cannot receive data from the network (invalid parameters)" << std::endl;
return Socket::Error;
}
}
////////////////////////////////////////////////////////////
/// Send a packet of data
////////////////////////////////////////////////////////////
Socket::Status SocketUDP::Send(Packet& PacketToSend, const IPAddress& Address, unsigned short Port)
{
// Get the data to send from the packet
std::size_t DataSize = 0;
const char* Data = PacketToSend.OnSend(DataSize);
// Send the packet size
Uint32 PacketSize = htonl(static_cast<unsigned long>(DataSize));
Send(reinterpret_cast<const char*>(&PacketSize), sizeof(PacketSize), Address, Port);
// Send the packet data
if (PacketSize > 0)
{
return Send(Data, DataSize, Address, Port);
}
else
{
return Socket::Done;
}
}
////////////////////////////////////////////////////////////
/// Receive a packet.
/// This function will block if the socket is blocking
////////////////////////////////////////////////////////////
Socket::Status SocketUDP::Receive(Packet& PacketToReceive, IPAddress& Address, unsigned short& Port)
{
// We start by getting the size of the incoming packet
Uint32 PacketSize = 0;
std::size_t Received = 0;
if (myPendingPacketSize < 0)
{
// Loop until we've received the entire size of the packet
// (even a 4 bytes variable may be received in more than one call)
while (myPendingHeaderSize < sizeof(myPendingHeader))
{
char* Data = reinterpret_cast<char*>(&myPendingHeader) + myPendingHeaderSize;
Socket::Status Status = Receive(Data, sizeof(myPendingHeader) - myPendingHeaderSize, Received, Address, Port);
myPendingHeaderSize += Received;
if (Status != Socket::Done)
return Status;
}
PacketSize = ntohl(myPendingHeader);
myPendingHeaderSize = 0;
}
else
{
// There is a pending packet : we already know its size
PacketSize = myPendingPacketSize;
}
// Use another address instance for receiving the packet data ;
// chunks of data coming from a different sender will be discarded (and lost...)
IPAddress Sender;
unsigned short SenderPort;
// Then loop until we receive all the packet data
char Buffer[1024];
while (myPendingPacket.size() < PacketSize)
{
// Receive a chunk of data
std::size_t SizeToGet = std::min(static_cast<std::size_t>(PacketSize - myPendingPacket.size()), sizeof(Buffer));
Socket::Status Status = Receive(Buffer, SizeToGet, Received, Sender, SenderPort);
if (Status != Socket::Done)
{
// We must save the size of the pending packet until we can receive its content
if (Status == Socket::NotReady)
myPendingPacketSize = PacketSize;
return Status;
}
// Append it into the packet
if ((Sender == Address) && (SenderPort == Port) && (Received > 0))
{
myPendingPacket.resize(myPendingPacket.size() + Received);
char* Begin = &myPendingPacket[0] + myPendingPacket.size() - Received;
memcpy(Begin, Buffer, Received);
}
}
// We have received all the datas : we can copy it to the user packet, and clear our internal packet
PacketToReceive.Clear();
if (!myPendingPacket.empty())
PacketToReceive.OnReceive(&myPendingPacket[0], myPendingPacket.size());
myPendingPacket.clear();
myPendingPacketSize = -1;
return Socket::Done;
}
////////////////////////////////////////////////////////////
/// Close the socket
////////////////////////////////////////////////////////////
bool SocketUDP::Close()
{
if (IsValid())
{
if (!SocketHelper::Close(mySocket))
{
std::cerr << "Failed to close socket" << std::endl;
return false;
}
mySocket = SocketHelper::InvalidSocket();
}
myPort = 0;
myIsBlocking = true;
return true;
}
////////////////////////////////////////////////////////////
/// Check if the socket is in a valid state ; this function
/// can be called any time to check if the socket is OK
////////////////////////////////////////////////////////////
bool SocketUDP::IsValid() const
{
return mySocket != SocketHelper::InvalidSocket();
}
////////////////////////////////////////////////////////////
/// Get the port the socket is currently bound to
////////////////////////////////////////////////////////////
unsigned short SocketUDP::GetPort() const
{
return myPort;
}
////////////////////////////////////////////////////////////
/// Comparison operator ==
////////////////////////////////////////////////////////////
bool SocketUDP::operator ==(const SocketUDP& Other) const
{
return mySocket == Other.mySocket;
}
////////////////////////////////////////////////////////////
/// Comparison operator !=
////////////////////////////////////////////////////////////
bool SocketUDP::operator !=(const SocketUDP& Other) const
{
return mySocket != Other.mySocket;
}
////////////////////////////////////////////////////////////
/// Comparison operator <.
/// Provided for compatibility with standard containers, as
/// comparing two sockets doesn't make much sense...
////////////////////////////////////////////////////////////
bool SocketUDP::operator <(const SocketUDP& Other) const
{
return mySocket < Other.mySocket;
}
////////////////////////////////////////////////////////////
/// Construct the socket from a socket descriptor
/// (for internal use only)
////////////////////////////////////////////////////////////
SocketUDP::SocketUDP(SocketHelper::SocketType Descriptor)
{
Create(Descriptor);
}
////////////////////////////////////////////////////////////
/// Create the socket
////////////////////////////////////////////////////////////
void SocketUDP::Create(SocketHelper::SocketType Descriptor)
{
// Use the given socket descriptor, or get a new one
mySocket = Descriptor ? Descriptor : socket(PF_INET, SOCK_DGRAM, 0);
myIsBlocking = true;
// Clear the last port used
myPort = 0;
// Reset the pending packet
myPendingHeaderSize = 0;
myPendingPacket.clear();
myPendingPacketSize = -1;
// Setup default options
if (IsValid())
{
// To avoid the "Address already in use" error message when trying to bind to the same port
int Yes = 1;
if (setsockopt(mySocket, SOL_SOCKET, SO_REUSEADDR, reinterpret_cast<char*>(&Yes), sizeof(Yes)) == -1)
{
std::cerr << "Failed to set socket option \"reuse address\" ; "
<< "binding to a same port may fail if too fast" << std::endl;
}
// Enable broadcast by default
if (setsockopt(mySocket, SOL_SOCKET, SO_BROADCAST, reinterpret_cast<char*>(&Yes), sizeof(Yes)) == -1)
{
std::cerr << "Failed to enable broadcast on UDP socket" << std::endl;
}
// Set blocking by default (should always be the case anyway)
SetBlocking(true);
}
}
} // namespace sf
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