/* 
 * tclWinSock.c --
 *
 *	This file contains Windows-specific socket related code.
 *
 * Copyright (c) 1995-1997 Sun Microsystems, Inc.
 *
 * See the file "license.terms" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * RCS: @(#) $Id: tclWinSock.c,v 1.44 2004/10/06 14:39:20 dkf Exp $
 */

#include "tclWinInt.h"

/*
 * Make sure to remove the redirection defines set in tclWinPort.h
 * that is in use in other sections of the core, except for us.

static Tcl_DriverOutputProc	TcpOutputProc;
static Tcl_DriverWatchProc	TcpWatchProc;
static Tcl_DriverGetHandleProc	TcpGetHandleProc;
static int		    WaitForSocketEvent _ANSI_ARGS_((
				SocketInfo *infoPtr, int events,
				int *errorCodePtr));
static DWORD WINAPI	    SocketThread _ANSI_ARGS_((LPVOID arg));





/*
 * This structure describes the channel type structure for TCP socket
 * based IO.
 */

static Tcl_ChannelType tcpChannelType = {
    "tcp",		    /* Type name. */
    TCL_CHANNEL_VERSION_2,  /* v2 channel */
    TcpCloseProc,	    /* Close proc. */
    TcpInputProc,	    /* Input proc. */
    TcpOutputProc,	    /* Output proc. */
    NULL,		    /* Seek proc. */
    TcpSetOptionProc,	    /* Set option proc. */
    TcpGetOptionProc,	    /* Get option proc. */
    TcpWatchProc,	    /* Set up notifier to watch this channel. */
    TcpGetHandleProc,	    /* Get an OS handle from channel. */
    NULL,		    /* close2proc. */
    TcpBlockProc,	    /* Set socket into (non-)blocking mode. */
    NULL,		    /* flush proc. */
    NULL,		    /* handler proc. */


};


/*
 *----------------------------------------------------------------------
 *
 * InitSockets --

    /* ARGSUSED */
static int
TcpCloseProc(instanceData, interp)
    ClientData instanceData;	/* The socket to close. */
    Tcl_Interp *interp;		/* Unused. */
{
    SocketInfo *infoPtr = (SocketInfo *) instanceData;
    SocketInfo **nextPtrPtr;
    int errorCode = 0;
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

    /*
     * Check that WinSock is initialized; do not call it if not, to
     * prevent system crashes. This can happen at exit time if the exit
     * handler for WinSock ran before other exit handlers that want to

    
        if (winSock.closesocket(infoPtr->socket) == SOCKET_ERROR) {
            TclWinConvertWSAError((DWORD) winSock.WSAGetLastError());
            errorCode = Tcl_GetErrno();
        }
    }

    /*
     * Remove the socket from socketList.



     */

    WaitForSingleObject(tsdPtr->socketListLock, INFINITE);
    for (nextPtrPtr = &(tsdPtr->socketList); (*nextPtrPtr) != NULL;
	 nextPtrPtr = &((*nextPtrPtr)->nextPtr)) {
	if ((*nextPtrPtr) == infoPtr) {
	    (*nextPtrPtr) = infoPtr->nextPtr;
	    break;
	}
    }
    
    SetEvent(tsdPtr->socketListLock);
    ckfree((char *) infoPtr);
    return errorCode;
}

/*
 *----------------------------------------------------------------------
 *
 * NewSocketInfo --
 *
 *	This function allocates and initializes a new SocketInfo
 *	structure.
 *
 * Results:
 *	Returns a newly allocated SocketInfo.
 *
 * Side effects:
 *	Adds the socket to the global socket list.
 *
 *----------------------------------------------------------------------
 */

static SocketInfo *
NewSocketInfo(socket)
    SOCKET socket;

    infoPtr->readyEvents = 0;
    infoPtr->selectEvents = 0;
    infoPtr->acceptEventCount = 0;
    infoPtr->acceptProc = NULL;
    infoPtr->acceptProcData = NULL;
    infoPtr->lastError = 0;

    WaitForSingleObject(tsdPtr->socketListLock, INFINITE);



    infoPtr->nextPtr = tsdPtr->socketList;
    tsdPtr->socketList = infoPtr;
    SetEvent(tsdPtr->socketListLock);
    
    return infoPtr;
}

/*
 *----------------------------------------------------------------------
 *
 * CreateSocket --
 *
 *	This function opens a new socket and initializes the
 *	SocketInfo structure.
 *
 * Results:
 *	Returns a new SocketInfo, or NULL with an error in interp.
 *
 * Side effects:
 *	Adds a new socket to the socketList.
 *
 *----------------------------------------------------------------------
 */

static SocketInfo *
CreateSocket(interp, port, host, server, myaddr, myport, async)
    Tcl_Interp *interp;		/* For error reporting; can be NULL. */

     */
    if (!SocketsEnabled()) {
        return (struct servent *) NULL;
    }

    return winSock.getservbyname(name, proto);
}



/*
 *----------------------------------------------------------------------
 *
 * TclpCutSockChannel --
 *
 *	Remove any thread local refs to this channel. See
 *	Tcl_CutChannel for more info.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Changes thread local list of valid channels.
 *
 *----------------------------------------------------------------------
 */

void
TclpCutSockChannel(chan)
    Tcl_Channel chan;			/* The channel being removed. Must
                                         * not be referenced in any
                                         * interpreter. */
{
    ThreadSpecificData *tsdPtr;
    SocketInfo *infoPtr;
    SocketInfo **nextPtrPtr;
    int removed = 0;






    if (Tcl_GetChannelType(chan) != &tcpChannelType) {

        return;

    }


    /*


     * The initializtion of tsdPtr _after_ we have determined that we
     * are dealing with socket is necessary. Doing it before causes
     * the module to access th tdsPtr when it is not initialized yet,


     * causing a lockup.
     */


    tsdPtr  = TCL_TSD_INIT(&dataKey);
    infoPtr = (SocketInfo *) Tcl_GetChannelInstanceData (chan);



    for (nextPtrPtr = &(tsdPtr->socketList); (*nextPtrPtr) != NULL;
	 nextPtrPtr = &((*nextPtrPtr)->nextPtr)) {
	if ((*nextPtrPtr) == infoPtr) {
	    (*nextPtrPtr) = infoPtr->nextPtr;
	    removed = 1;
	    break;
	}
    }


    /*
     * This could happen if the channel was created in one thread
     * and then moved to another without updating the thread
     * local data in each thread.
     */

    if (!removed) {
        Tcl_Panic("file info ptr not on thread channel list");
    }

    /*
     * Stop notifications for the socket to occur in this thread.
     */

    SendMessage(tsdPtr->hwnd, SOCKET_SELECT,
		(WPARAM) UNSELECT, (LPARAM) infoPtr);
}

/*
 *----------------------------------------------------------------------
 *
 * TclpSpliceSockChannel --
 *
 *	Insert thread local ref for this channel.
 *	Tcl_SpliceChannel for more info.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Changes thread local list of valid channels.
 *
 *----------------------------------------------------------------------
 */

void
TclpSpliceSockChannel(chan)
    Tcl_Channel chan;			/* The channel being removed. Must
                                         * not be referenced in any
                                         * interpreter. */
{
    ThreadSpecificData *tsdPtr;
    SocketInfo *infoPtr;

    if (Tcl_GetChannelType(chan) != &tcpChannelType) {
        return;
    }

    /*
     * Ensure that socket subsystem is initialized in this thread, or
     * else sockets will not work.
     */

    Tcl_MutexLock(&socketMutex);
    InitSockets();
    Tcl_MutexUnlock(&socketMutex);

    /*
     * The initializtion of tsdPtr _after_ we have determined that we
     * are dealing with socket is necessary. Doing it before causes
     * the module to access th tdsPtr when it is not initialized yet,
     * causing a lockup.
     */

    tsdPtr  = TCL_TSD_INIT(&dataKey);
    infoPtr = (SocketInfo *) Tcl_GetChannelInstanceData (chan);

    WaitForSingleObject(tsdPtr->socketListLock, INFINITE);
    infoPtr->nextPtr = tsdPtr->socketList;
    tsdPtr->socketList = infoPtr;
    SetEvent(tsdPtr->socketListLock);

    /*
     * Ensure that notifications for the socket occur in this thread.
     */

    SendMessage(tsdPtr->hwnd, SOCKET_SELECT,
		(WPARAM) SELECT, (LPARAM) infoPtr);
}