McRogueFace/deps_linux/SFML/Network/SocketSelector.hpp

264 lines
9.1 KiB
C++

////////////////////////////////////////////////////////////
//
// SFML - Simple and Fast Multimedia Library
// Copyright (C) 2007-2018 Laurent Gomila (laurent@sfml-dev.org)
//
// 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.
//
////////////////////////////////////////////////////////////
#ifndef SFML_SOCKETSELECTOR_HPP
#define SFML_SOCKETSELECTOR_HPP
////////////////////////////////////////////////////////////
// Headers
////////////////////////////////////////////////////////////
#include <SFML/Network/Export.hpp>
#include <SFML/System/Time.hpp>
namespace sf
{
class Socket;
////////////////////////////////////////////////////////////
/// \brief Multiplexer that allows to read from multiple sockets
///
////////////////////////////////////////////////////////////
class SFML_NETWORK_API SocketSelector
{
public:
////////////////////////////////////////////////////////////
/// \brief Default constructor
///
////////////////////////////////////////////////////////////
SocketSelector();
////////////////////////////////////////////////////////////
/// \brief Copy constructor
///
/// \param copy Instance to copy
///
////////////////////////////////////////////////////////////
SocketSelector(const SocketSelector& copy);
////////////////////////////////////////////////////////////
/// \brief Destructor
///
////////////////////////////////////////////////////////////
~SocketSelector();
////////////////////////////////////////////////////////////
/// \brief Add a new socket to the selector
///
/// This function keeps a weak reference to the socket,
/// so you have to make sure that the socket is not destroyed
/// while it is stored in the selector.
/// This function does nothing if the socket is not valid.
///
/// \param socket Reference to the socket to add
///
/// \see remove, clear
///
////////////////////////////////////////////////////////////
void add(Socket& socket);
////////////////////////////////////////////////////////////
/// \brief Remove a socket from the selector
///
/// This function doesn't destroy the socket, it simply
/// removes the reference that the selector has to it.
///
/// \param socket Reference to the socket to remove
///
/// \see add, clear
///
////////////////////////////////////////////////////////////
void remove(Socket& socket);
////////////////////////////////////////////////////////////
/// \brief Remove all the sockets stored in the selector
///
/// This function doesn't destroy any instance, it simply
/// removes all the references that the selector has to
/// external sockets.
///
/// \see add, remove
///
////////////////////////////////////////////////////////////
void clear();
////////////////////////////////////////////////////////////
/// \brief Wait until one or more sockets are ready to receive
///
/// This function returns as soon as at least one socket has
/// some data available to be received. To know which sockets are
/// ready, use the isReady function.
/// If you use a timeout and no socket is ready before the timeout
/// is over, the function returns false.
///
/// \param timeout Maximum time to wait, (use Time::Zero for infinity)
///
/// \return True if there are sockets ready, false otherwise
///
/// \see isReady
///
////////////////////////////////////////////////////////////
bool wait(Time timeout = Time::Zero);
////////////////////////////////////////////////////////////
/// \brief Test a socket to know if it is ready to receive data
///
/// This function must be used after a call to Wait, to know
/// which sockets are ready to receive data. If a socket is
/// ready, a call to receive will never block because we know
/// that there is data available to read.
/// Note that if this function returns true for a TcpListener,
/// this means that it is ready to accept a new connection.
///
/// \param socket Socket to test
///
/// \return True if the socket is ready to read, false otherwise
///
/// \see isReady
///
////////////////////////////////////////////////////////////
bool isReady(Socket& socket) const;
////////////////////////////////////////////////////////////
/// \brief Overload of assignment operator
///
/// \param right Instance to assign
///
/// \return Reference to self
///
////////////////////////////////////////////////////////////
SocketSelector& operator =(const SocketSelector& right);
private:
struct SocketSelectorImpl;
////////////////////////////////////////////////////////////
// Member data
////////////////////////////////////////////////////////////
SocketSelectorImpl* m_impl; ///< Opaque pointer to the implementation (which requires OS-specific types)
};
} // namespace sf
#endif // SFML_SOCKETSELECTOR_HPP
////////////////////////////////////////////////////////////
/// \class sf::SocketSelector
/// \ingroup network
///
/// Socket selectors provide a way to wait until some data is
/// available on a set of sockets, instead of just one. This
/// is convenient when you have multiple sockets that may
/// possibly receive data, but you don't know which one will
/// be ready first. In particular, it avoids to use a thread
/// for each socket; with selectors, a single thread can handle
/// all the sockets.
///
/// All types of sockets can be used in a selector:
/// \li sf::TcpListener
/// \li sf::TcpSocket
/// \li sf::UdpSocket
///
/// A selector doesn't store its own copies of the sockets
/// (socket classes are not copyable anyway), it simply keeps
/// a reference to the original sockets that you pass to the
/// "add" function. Therefore, you can't use the selector as a
/// socket container, you must store them outside and make sure
/// that they are alive as long as they are used in the selector.
///
/// Using a selector is simple:
/// \li populate the selector with all the sockets that you want to observe
/// \li make it wait until there is data available on any of the sockets
/// \li test each socket to find out which ones are ready
///
/// Usage example:
/// \code
/// // Create a socket to listen to new connections
/// sf::TcpListener listener;
/// listener.listen(55001);
///
/// // Create a list to store the future clients
/// std::list<sf::TcpSocket*> clients;
///
/// // Create a selector
/// sf::SocketSelector selector;
///
/// // Add the listener to the selector
/// selector.add(listener);
///
/// // Endless loop that waits for new connections
/// while (running)
/// {
/// // Make the selector wait for data on any socket
/// if (selector.wait())
/// {
/// // Test the listener
/// if (selector.isReady(listener))
/// {
/// // The listener is ready: there is a pending connection
/// sf::TcpSocket* client = new sf::TcpSocket;
/// if (listener.accept(*client) == sf::Socket::Done)
/// {
/// // Add the new client to the clients list
/// clients.push_back(client);
///
/// // Add the new client to the selector so that we will
/// // be notified when he sends something
/// selector.add(*client);
/// }
/// else
/// {
/// // Error, we won't get a new connection, delete the socket
/// delete client;
/// }
/// }
/// else
/// {
/// // The listener socket is not ready, test all other sockets (the clients)
/// for (std::list<sf::TcpSocket*>::iterator it = clients.begin(); it != clients.end(); ++it)
/// {
/// sf::TcpSocket& client = **it;
/// if (selector.isReady(client))
/// {
/// // The client has sent some data, we can receive it
/// sf::Packet packet;
/// if (client.receive(packet) == sf::Socket::Done)
/// {
/// ...
/// }
/// }
/// }
/// }
/// }
/// }
/// \endcode
///
/// \see sf::Socket
///
////////////////////////////////////////////////////////////