/////////////////////////////////////////////////////////////////////////////

// Name:        wx/private/selectdispatcher.h

// Purpose:     wxSelectDispatcher class

// Authors:     Lukasz Michalski and Vadim Zeitlin

// Created:     December 2006

// Copyright:   (c) Lukasz Michalski

// Licence:     wxWindows licence

/////////////////////////////////////////////////////////////////////////////

#ifndef _WX_PRIVATE_SELECTDISPATCHER_H_

#define _WX_PRIVATE_SELECTDISPATCHER_H_

#include "wx/defs.h"

#if wxUSE_SELECT_DISPATCHER

#if defined(HAVE_SYS_SELECT_H)

    #include <sys/time.h>

    #include <sys/select.h>

#endif

#include <sys/types.h>

#include "wx/thread.h"

#include "wx/private/fdiodispatcher.h"

// helper class storing all the select() fd sets

class WXDLLIMPEXP_BASE wxSelectSets

{

public:

    // ctor zeroes out all fd_sets

    wxSelectSets();

    // default copy ctor, assignment operator and dtor are ok

    // return true if fd appears in any of the sets

    bool HasFD(int fd) const;

    // add or remove FD to our sets depending on whether flags contains

    // wxFDIO_INPUT/OUTPUT/EXCEPTION bits

    bool SetFD(int fd, int flags);

    // same as SetFD() except it unsets the bits set in the flags for the given

    // fd

    bool ClearFD(int fd)

    {

        return SetFD(fd, 0);

    }

    // call select() with our sets: the other parameters are the same as for

    // select() itself

    int Select(int nfds, struct timeval *tv);

    // call the handler methods corresponding to the sets having this fd if it

    // is present in any set and return true if it is

    bool Handle(int fd, wxFDIOHandler& handler) const;

private:

    typedef void (wxFDIOHandler::*Callback)();

    // the FD sets indices

    enum

    {

        Read,

        Write,

        Except,

        Max

    };

    // the sets used with select()

    fd_set m_fds[Max];

    // the wxFDIO_XXX flags, functions and names (used for debug messages only)

    // corresponding to the FD sets above

    static int ms_flags[Max];

    static const char *ms_names[Max];

    static Callback ms_handlers[Max];

};

class WXDLLIMPEXP_BASE wxSelectDispatcher : public wxMappedFDIODispatcher

{

public:

    // default ctor

    wxSelectDispatcher() { m_maxFD = -1; }

    // implement pure virtual methods of the base class

    virtual bool RegisterFD(int fd, wxFDIOHandler *handler, int flags = wxFDIO_ALL) override;

    virtual bool ModifyFD(int fd, wxFDIOHandler *handler, int flags = wxFDIO_ALL) override;

    virtual bool UnregisterFD(int fd) override;

    virtual bool HasPending() const override;

    virtual int Dispatch(int timeout = TIMEOUT_INFINITE) override;

private:

    // common part of RegisterFD() and ModifyFD()

    bool DoUpdateFDAndHandler(int fd, wxFDIOHandler *handler, int flags);

    // call the handlers for the fds present in the given sets, return the

    // number of handlers we called

    int ProcessSets(const wxSelectSets& sets);

    // helper of ProcessSets(): call the handler if its fd is in the set

    void DoProcessFD(int fd, const fd_set& fds, wxFDIOHandler *handler,

                     const char *name);

    // common part of HasPending() and Dispatch(): calls select() with the

    // specified timeout

    int DoSelect(wxSelectSets& sets, int timeout) const;

#if wxUSE_THREADS

    wxCriticalSection m_cs;

#endif // wxUSE_THREADS

    // the select sets containing all the registered fds

    wxSelectSets m_sets;

    // the highest registered fd value or -1 if none

    int m_maxFD;

};

#endif // wxUSE_SELECT_DISPATCHER

#endif // _WX_PRIVATE_SOCKETEVTDISPATCH_H_