SelectorBase.cpp

//
// 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.
//

#ifdef _MSC_VER
    #pragma warning(disable : 4127) // "conditional expression is constant" generated by the FD_SET macro
#endif

// Headers
#include <SFML/Network/SelectorBase.hpp>


namespace sf
{
SelectorBase::SelectorBase() :
myMaxSocket(0)
{
    Clear();
}


void SelectorBase::Add(SocketHelper::SocketType socket)
{
    FD_SET(socket, &mySet);

    int size = static_cast<int>(socket);
    if (size > myMaxSocket)
        myMaxSocket = size;
}


void SelectorBase::Remove(SocketHelper::SocketType socket)
{
    FD_CLR(socket, &mySet);
}


void SelectorBase::Clear()
{
    FD_ZERO(&mySet);
    FD_ZERO(&mySetReady);

    myMaxSocket = 0;
}


unsigned int SelectorBase::Wait(float timeout)
{
    // Setup the timeout structure
    timeval time;
    time.tv_sec  = static_cast<long>(timeout);
    time.tv_usec = (static_cast<long>(timeout * 1000) % 1000) * 1000;

    // Prepare the set of sockets to return
    mySetReady = mySet;

    // Wait until one of the sockets is ready for reading, or timeout is reached
    int nbSockets = select(myMaxSocket + 1, &mySetReady, NULL, NULL, timeout > 0 ? &time : NULL);

    return nbSockets >= 0 ? static_cast<unsigned int>(nbSockets) : 0;
}


SocketHelper::SocketType SelectorBase::GetSocketReady(unsigned int index) const
{
    // We have to drop the const for FD_ISSET
    fd_set* set = const_cast<fd_set*>(&mySetReady);

    // The standard FD_xxx interface doesn't define a direct access,
    // so we must iterate through the whole set to find the socket that we're looking for
    for (int i = 0; i < myMaxSocket + 1; ++i)
    {
        if (FD_ISSET(i, set))
        {
            // Current socket is ready, but is it the index-th one ?
            if (index > 0)
            {
                index--;
            }
            else
            {
                return static_cast<SocketHelper::SocketType>(i);
            }
        }
    }

    // Invalid index : return an invalid socket
    return SocketHelper::InvalidSocket();
}

} // namespace sf

 ::  Copyright © 2007-2008 Laurent Gomila, all rights reserved  ::  Documentation generated by doxygen 1.5.2  ::