source: downloads/tcl8.5.2/win/tclWinDde.c @ 45

/*
 * tclWinDde.c --
 *
 *      This file provides functions that implement the "send" command,
 *      allowing commands to be passed from interpreter to interpreter.
 *
 * Copyright (c) 1997 by 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: tclWinDde.c,v 1.31 2006/09/26 00:05:03 patthoyts Exp $
 */

#include "tclInt.h"
#include <dde.h>
#include <ddeml.h>
#include <tchar.h>

/*
 * TCL_STORAGE_CLASS is set unconditionally to DLLEXPORT because the Dde_Init
 * declaration is in the source file itself, which is only accessed when we
 * are building a library. DO NOT MOVE BEFORE ANY #include LINES. ONLY USE
 * EXTERN TO INDICATE EXPORTED FUNCTIONS FROM NOW ON.
 */

#undef TCL_STORAGE_CLASS
#define TCL_STORAGE_CLASS DLLEXPORT

/*
 * The following structure is used to keep track of the interpreters
 * registered by this process.
 */

typedef struct RegisteredInterp {
    struct RegisteredInterp *nextPtr;
                                /* The next interp this application knows
                                 * about. */
    char *name;                 /* Interpreter's name (malloc-ed). */
    Tcl_Obj *handlerPtr;        /* The server handler command */
    Tcl_Interp *interp;         /* The interpreter attached to this name. */
} RegisteredInterp;

/*
 * Used to keep track of conversations.
 */

typedef struct Conversation {
    struct Conversation *nextPtr;
                                /* The next conversation in the list. */
    RegisteredInterp *riPtr;    /* The info we know about the conversation. */
    HCONV hConv;                /* The DDE handle for this conversation. */
    Tcl_Obj *returnPackagePtr;  /* The result package for this conversation. */
} Conversation;

typedef struct DdeEnumServices {
    Tcl_Interp *interp;
    int result;
    ATOM service;
    ATOM topic;
    HWND hwnd;
} DdeEnumServices;

typedef struct ThreadSpecificData {
    Conversation *currentConversations;
                                /* A list of conversations currently being
                                 * processed. */
    RegisteredInterp *interpListPtr;
                                /* List of all interpreters registered in the
                                 * current process. */
} ThreadSpecificData;
static Tcl_ThreadDataKey dataKey;

/*
 * The following variables cannot be placed in thread-local storage. The Mutex
 * ddeMutex guards access to the ddeInstance.
 */

static HSZ ddeServiceGlobal = 0;
static DWORD ddeInstance;       /* The application instance handle given to us
                                 * by DdeInitialize. */
static int ddeIsServer = 0;

#define TCL_DDE_VERSION         "1.3.2"
#define TCL_DDE_PACKAGE_NAME    "dde"
#define TCL_DDE_SERVICE_NAME    "TclEval"
#define TCL_DDE_EXECUTE_RESULT  "$TCLEVAL$EXECUTE$RESULT"

TCL_DECLARE_MUTEX(ddeMutex)

/*
 * Forward declarations for functions defined later in this file.
 */

static LRESULT CALLBACK DdeClientWindowProc(HWND hwnd, UINT uMsg,
                            WPARAM wParam, LPARAM lParam);
static int              DdeCreateClient(struct DdeEnumServices *es);
static BOOL CALLBACK    DdeEnumWindowsCallback(HWND hwndTarget, LPARAM lParam);
static void             DdeExitProc(ClientData clientData);
static int              DdeGetServicesList(Tcl_Interp *interp,
                            char *serviceName, char *topicName);
static HDDEDATA CALLBACK DdeServerProc(UINT uType, UINT uFmt, HCONV hConv,
                            HSZ ddeTopic, HSZ ddeItem, HDDEDATA hData,
                            DWORD dwData1, DWORD dwData2);
static LRESULT          DdeServicesOnAck(HWND hwnd, WPARAM wParam,
                            LPARAM lParam);
static void             DeleteProc(ClientData clientData);
static Tcl_Obj *        ExecuteRemoteObject(RegisteredInterp *riPtr,
                            Tcl_Obj *ddeObjectPtr);
static int              MakeDdeConnection(Tcl_Interp *interp, char *name,
                            HCONV *ddeConvPtr);
static void             SetDdeError(Tcl_Interp *interp);

int                     Tcl_DdeObjCmd(ClientData clientData,
                            Tcl_Interp *interp, int objc,
                            Tcl_Obj *CONST objv[]);

EXTERN int              Dde_Init(Tcl_Interp *interp);
EXTERN int              Dde_SafeInit(Tcl_Interp *interp);

/*
 *----------------------------------------------------------------------
 *
 * Dde_Init --
 *
 *      This function initializes the dde command.
 *
 * Results:
 *      A standard Tcl result.
 *
 * Side effects:
 *      None.
 *
 *----------------------------------------------------------------------
 */

int
Dde_Init(
    Tcl_Interp *interp)
{
    ThreadSpecificData *tsdPtr;

    if (!Tcl_InitStubs(interp, "8.0", 0)) {
        return TCL_ERROR;
    }

    Tcl_CreateObjCommand(interp, "dde", Tcl_DdeObjCmd, NULL, NULL);
    tsdPtr = TCL_TSD_INIT(&dataKey);
    Tcl_CreateExitHandler(DdeExitProc, NULL);
    return Tcl_PkgProvide(interp, TCL_DDE_PACKAGE_NAME, TCL_DDE_VERSION);
}

/*
 *----------------------------------------------------------------------
 *
 * Dde_SafeInit --
 *
 *      This function initializes the dde command within a safe interp
 *
 * Results:
 *      A standard Tcl result.
 *
 * Side effects:
 *      None.
 *
 *----------------------------------------------------------------------
 */

int
Dde_SafeInit(
    Tcl_Interp *interp)
{
    int result = Dde_Init(interp);
    if (result == TCL_OK) {
        Tcl_HideCommand(interp, "dde", "dde");
    }
    return result;
}

/*
 *----------------------------------------------------------------------
 *
 * Initialize --
 *
 *      Initialize the global DDE instance.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Registers the DDE server proc.
 *
 *----------------------------------------------------------------------
 */

static void
Initialize(void)
{
    int nameFound = 0;
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

    /*
     * See if the application is already registered; if so, remove its current
     * name from the registry. The deletion of the command will take care of
     * disposing of this entry.
     */

    if (tsdPtr->interpListPtr != NULL) {
        nameFound = 1;
    }

    /*
     * Make sure that the DDE server is there. This is done only once, add an
     * exit handler tear it down.
     */

    if (ddeInstance == 0) {
        Tcl_MutexLock(&ddeMutex);
        if (ddeInstance == 0) {
            if (DdeInitialize(&ddeInstance, DdeServerProc,
                    CBF_SKIP_REGISTRATIONS | CBF_SKIP_UNREGISTRATIONS
                    | CBF_FAIL_POKES, 0) != DMLERR_NO_ERROR) {
                ddeInstance = 0;
            }
        }
        Tcl_MutexUnlock(&ddeMutex);
    }
    if ((ddeServiceGlobal == 0) && (nameFound != 0)) {
        Tcl_MutexLock(&ddeMutex);
        if ((ddeServiceGlobal == 0) && (nameFound != 0)) {
            ddeIsServer = 1;
            Tcl_CreateExitHandler(DdeExitProc, NULL);
            ddeServiceGlobal = DdeCreateStringHandle(ddeInstance,
                    TCL_DDE_SERVICE_NAME, 0);
            DdeNameService(ddeInstance, ddeServiceGlobal, 0L, DNS_REGISTER);
        } else {
            ddeIsServer = 0;
        }
        Tcl_MutexUnlock(&ddeMutex);
    }
}

/*
 *----------------------------------------------------------------------
 *
 * DdeSetServerName --
 *
 *      This function is called to associate an ASCII name with a Dde server.
 *      If the interpreter has already been named, the name replaces the old
 *      one.
 *
 * Results:
 *      The return value is the name actually given to the interp. This will
 *      normally be the same as name, but if name was already in use for a Dde
 *      Server then a name of the form "name #2" will be chosen, with a high
 *      enough number to make the name unique.
 *
 * Side effects:
 *      Registration info is saved, thereby allowing the "send" command to be
 *      used later to invoke commands in the application. In addition, the
 *      "send" command is created in the application's interpreter. The
 *      registration will be removed automatically if the interpreter is
 *      deleted or the "send" command is removed.
 *
 *----------------------------------------------------------------------
 */

static char *
DdeSetServerName(
    Tcl_Interp *interp,
    char *name,                 /* The name that will be used to refer to the
                                 * interpreter in later "send" commands. Must
                                 * be globally unique. */
    int exactName,              /* Should we make a unique name? 0 = unique */
    Tcl_Obj *handlerPtr)        /* Name of the optional proc/command to handle
                                 * incoming Dde eval's */
{
    int suffix, offset;
    RegisteredInterp *riPtr, *prevPtr;
    Tcl_DString dString;
    char *actualName;
    Tcl_Obj *srvListPtr = NULL, **srvPtrPtr = NULL;
    int n, srvCount = 0, lastSuffix, r = TCL_OK;
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

    /*
     * See if the application is already registered; if so, remove its current
     * name from the registry. The deletion of the command will take care of
     * disposing of this entry.
     */

    for (riPtr = tsdPtr->interpListPtr, prevPtr = NULL; riPtr != NULL;
            prevPtr = riPtr, riPtr = riPtr->nextPtr) {
        if (riPtr->interp == interp) {
            if (name != NULL) {
                if (prevPtr == NULL) {
                    tsdPtr->interpListPtr = tsdPtr->interpListPtr->nextPtr;
                } else {
                    prevPtr->nextPtr = riPtr->nextPtr;
                }
                break;
            } else {
                /*
                 * The name was NULL, so the caller is asking for the name of
                 * the current interp.
                 */

                return riPtr->name;
            }
        }
    }

    if (name == NULL) {
        /*
         * The name was NULL, so the caller is asking for the name of the
         * current interp, but it doesn't have a name.
         */

        return "";
    }

    /*
     * Get the list of currently registered Tcl interpreters by calling the
     * internal implementation of the 'dde services' command.
     */

    Tcl_DStringInit(&dString);
    actualName = name;

    if (!exactName) {
        r = DdeGetServicesList(interp, TCL_DDE_SERVICE_NAME, NULL);
        if (r == TCL_OK) {
            srvListPtr = Tcl_GetObjResult(interp);
        }
        if (r == TCL_OK) {
            r = Tcl_ListObjGetElements(interp, srvListPtr, &srvCount,
                    &srvPtrPtr);
        }
        if (r != TCL_OK) {
            OutputDebugString(Tcl_GetStringResult(interp));
            return NULL;
        }

        /*
         * Pick a name to use for the application. Use "name" if it's not
         * already in use. Otherwise add a suffix such as " #2", trying larger
         * and larger numbers until we eventually find one that is unique.
         */

        offset = lastSuffix = 0;
        suffix = 1;

        while (suffix != lastSuffix) {
            lastSuffix = suffix;
            if (suffix > 1) {
                if (suffix == 2) {
                    Tcl_DStringAppend(&dString, name, -1);
                    Tcl_DStringAppend(&dString, " #", 2);
                    offset = Tcl_DStringLength(&dString);
                    Tcl_DStringSetLength(&dString, offset + TCL_INTEGER_SPACE);
                    actualName = Tcl_DStringValue(&dString);
                }
                sprintf(Tcl_DStringValue(&dString) + offset, "%d", suffix);
            }

            /*
             * See if the name is already in use, if so increment suffix.
             */

            for (n = 0; n < srvCount; ++n) {
                Tcl_Obj* namePtr;

                Tcl_ListObjIndex(interp, srvPtrPtr[n], 1, &namePtr);
                if (strcmp(actualName, Tcl_GetString(namePtr)) == 0) {
                    suffix++;
                    break;
                }
            }
        }
        Tcl_DStringSetLength(&dString,
                offset + (int)strlen(Tcl_DStringValue(&dString)+offset));
    }

    /*
     * We have found a unique name. Now add it to the registry.
     */

    riPtr = (RegisteredInterp *) ckalloc(sizeof(RegisteredInterp));
    riPtr->interp = interp;
    riPtr->name = ckalloc((unsigned int) strlen(actualName) + 1);
    riPtr->nextPtr = tsdPtr->interpListPtr;
    riPtr->handlerPtr = handlerPtr;
    if (riPtr->handlerPtr != NULL) {
        Tcl_IncrRefCount(riPtr->handlerPtr);
    }
    tsdPtr->interpListPtr = riPtr;
    strcpy(riPtr->name, actualName);

    if (Tcl_IsSafe(interp)) {
        Tcl_ExposeCommand(interp, "dde", "dde");
    }

    Tcl_CreateObjCommand(interp, "dde", Tcl_DdeObjCmd,
            (ClientData) riPtr, DeleteProc);
    if (Tcl_IsSafe(interp)) {
        Tcl_HideCommand(interp, "dde", "dde");
    }
    Tcl_DStringFree(&dString);

    /*
     * Re-initialize with the new name.
     */

    Initialize();

    return riPtr->name;
}

/*
 *----------------------------------------------------------------------
 *
 * DdeGetRegistrationPtr
 *
 *      Retrieve the registration info for an interpreter.
 *
 * Results:
 *      Returns a pointer to the registration structure or NULL
 *
 * Side effects:
 *      None
 *
 *----------------------------------------------------------------------
 */

static RegisteredInterp *
DdeGetRegistrationPtr(
    Tcl_Interp *interp)
{
    RegisteredInterp *riPtr;
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

    for (riPtr = tsdPtr->interpListPtr; riPtr != NULL;
            riPtr = riPtr->nextPtr) {
        if (riPtr->interp == interp) {
            break;
        }
    }
    return riPtr;
}

/*
 *----------------------------------------------------------------------
 *
 * DeleteProc
 *
 *      This function is called when the command "dde" is destroyed.
 *
 * Results:
 *      none
 *
 * Side effects:
 *      The interpreter given by riPtr is unregistered.
 *
 *----------------------------------------------------------------------
 */

static void
DeleteProc(
    ClientData clientData)      /* The interp we are deleting passed as
                                 * ClientData. */
{
    RegisteredInterp *riPtr = (RegisteredInterp *) clientData;
    RegisteredInterp *searchPtr, *prevPtr;
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

    for (searchPtr = tsdPtr->interpListPtr, prevPtr = NULL;
            searchPtr != NULL && searchPtr != riPtr;
            prevPtr = searchPtr, searchPtr = searchPtr->nextPtr) {
        /*
         * Empty loop body.
         */
    }

    if (searchPtr != NULL) {
        if (prevPtr == NULL) {
            tsdPtr->interpListPtr = tsdPtr->interpListPtr->nextPtr;
        } else {
            prevPtr->nextPtr = searchPtr->nextPtr;
        }
    }
    ckfree(riPtr->name);
    if (riPtr->handlerPtr) {
        Tcl_DecrRefCount(riPtr->handlerPtr);
    }
    Tcl_EventuallyFree(clientData, TCL_DYNAMIC);
}

/*
 *----------------------------------------------------------------------
 *
 * ExecuteRemoteObject --
 *
 *      Takes the package delivered by DDE and executes it in the server's
 *      interpreter.
 *
 * Results:
 *      A list Tcl_Obj * that describes what happened. The first element is
 *      the numerical return code (TCL_ERROR, etc.). The second element is the
 *      result of the script. If the return result was TCL_ERROR, then the
 *      third element will be the value of the global "errorCode", and the
 *      fourth will be the value of the global "errorInfo". The return result
 *      will have a refCount of 0.
 *
 * Side effects:
 *      A Tcl script is run, which can cause all kinds of other things to
 *      happen.
 *
 *----------------------------------------------------------------------
 */

static Tcl_Obj *
ExecuteRemoteObject(
    RegisteredInterp *riPtr,        /* Info about this server. */
    Tcl_Obj *ddeObjectPtr)          /* The object to execute. */
{
    Tcl_Obj *returnPackagePtr;
    int result = TCL_OK;

    if (riPtr->handlerPtr == NULL && Tcl_IsSafe(riPtr->interp)) {
        Tcl_SetObjResult(riPtr->interp, Tcl_NewStringObj("permission denied: "
                "a handler procedure must be defined for use in a safe "
                "interp", -1));
        result = TCL_ERROR;
    }

    if (riPtr->handlerPtr != NULL) {
        /*
         * Add the dde request data to the handler proc list.
         */

        Tcl_Obj *cmdPtr = Tcl_DuplicateObj(riPtr->handlerPtr);

        result = Tcl_ListObjAppendElement(riPtr->interp, cmdPtr, ddeObjectPtr);
        if (result == TCL_OK) {
            ddeObjectPtr = cmdPtr;
        }
    }

    if (result == TCL_OK) {
        result = Tcl_EvalObjEx(riPtr->interp, ddeObjectPtr, TCL_EVAL_GLOBAL);
    }

    returnPackagePtr = Tcl_NewListObj(0, NULL);

    Tcl_ListObjAppendElement(NULL, returnPackagePtr, Tcl_NewIntObj(result));
    Tcl_ListObjAppendElement(NULL, returnPackagePtr,
            Tcl_GetObjResult(riPtr->interp));

    if (result == TCL_ERROR) {
        Tcl_Obj *errorObjPtr = Tcl_GetVar2Ex(riPtr->interp, "errorCode", NULL,
                TCL_GLOBAL_ONLY);
        if (errorObjPtr) {
            Tcl_ListObjAppendElement(NULL, returnPackagePtr, errorObjPtr);
        }
        errorObjPtr = Tcl_GetVar2Ex(riPtr->interp, "errorInfo", NULL,
                TCL_GLOBAL_ONLY);
        if (errorObjPtr) {
            Tcl_ListObjAppendElement(NULL, returnPackagePtr, errorObjPtr);
        }
    }

    return returnPackagePtr;
}

/*
 *----------------------------------------------------------------------
 *
 * DdeServerProc --
 *
 *      Handles all transactions for this server. Can handle execute, request,
 *      and connect protocols. Dde will call this routine when a client
 *      attempts to run a dde command using this server.
 *
 * Results:
 *      A DDE Handle with the result of the dde command.
 *
 * Side effects:
 *      Depending on which command is executed, arbitrary Tcl scripts can be
 *      run.
 *
 *----------------------------------------------------------------------
 */

static HDDEDATA CALLBACK
DdeServerProc(
    UINT uType,                 /* The type of DDE transaction we are
                                 * performing. */
    UINT uFmt,                  /* The format that data is sent or received. */
    HCONV hConv,                /* The conversation associated with the
                                 * current transaction. */
    HSZ ddeTopic, HSZ ddeItem,  /* String handles. Transaction-type
                                 * dependent. */
    HDDEDATA hData,             /* DDE data. Transaction-type dependent. */
    DWORD dwData1, DWORD dwData2)
                                /* Transaction-dependent data. */
{
    Tcl_DString dString;
    int len;
    DWORD dlen;
    char *utilString;
    Tcl_Obj *ddeObjectPtr;
    HDDEDATA ddeReturn = NULL;
    RegisteredInterp *riPtr;
    Conversation *convPtr, *prevConvPtr;
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

    switch(uType) {
    case XTYP_CONNECT:
        /*
         * Dde is trying to initialize a conversation with us. Check and make
         * sure we have a valid topic.
         */

        len = DdeQueryString(ddeInstance, ddeTopic, NULL, 0, 0);
        Tcl_DStringInit(&dString);
        Tcl_DStringSetLength(&dString, len);
        utilString = Tcl_DStringValue(&dString);
        DdeQueryString(ddeInstance, ddeTopic, utilString, (DWORD) len + 1,
                CP_WINANSI);

        for (riPtr = tsdPtr->interpListPtr; riPtr != NULL;
                riPtr = riPtr->nextPtr) {
            if (stricmp(utilString, riPtr->name) == 0) {
                Tcl_DStringFree(&dString);
                return (HDDEDATA) TRUE;
            }
        }

        Tcl_DStringFree(&dString);
        return (HDDEDATA) FALSE;

    case XTYP_CONNECT_CONFIRM:
        /*
         * Dde has decided that we can connect, so it gives us a conversation
         * handle. We need to keep track of it so we know which execution
         * result to return in an XTYP_REQUEST.
         */

        len = DdeQueryString(ddeInstance, ddeTopic, NULL, 0, 0);
        Tcl_DStringInit(&dString);
        Tcl_DStringSetLength(&dString, len);
        utilString = Tcl_DStringValue(&dString);
        DdeQueryString(ddeInstance, ddeTopic, utilString, (DWORD) len + 1,
                CP_WINANSI);
        for (riPtr = tsdPtr->interpListPtr; riPtr != NULL;
                riPtr = riPtr->nextPtr) {
            if (stricmp(riPtr->name, utilString) == 0) {
                convPtr = (Conversation *) ckalloc(sizeof(Conversation));
                convPtr->nextPtr = tsdPtr->currentConversations;
                convPtr->returnPackagePtr = NULL;
                convPtr->hConv = hConv;
                convPtr->riPtr = riPtr;
                tsdPtr->currentConversations = convPtr;
                break;
            }
        }
        Tcl_DStringFree(&dString);
        return (HDDEDATA) TRUE;

    case XTYP_DISCONNECT:
        /*
         * The client has disconnected from our server. Forget this
         * conversation.
         */

        for (convPtr = tsdPtr->currentConversations, prevConvPtr = NULL;
                convPtr != NULL;
                prevConvPtr = convPtr, convPtr = convPtr->nextPtr) {
            if (hConv == convPtr->hConv) {
                if (prevConvPtr == NULL) {
                    tsdPtr->currentConversations = convPtr->nextPtr;
                } else {
                    prevConvPtr->nextPtr = convPtr->nextPtr;
                }
                if (convPtr->returnPackagePtr != NULL) {
                    Tcl_DecrRefCount(convPtr->returnPackagePtr);
                }
                ckfree((char *) convPtr);
                break;
            }
        }
        return (HDDEDATA) TRUE;

    case XTYP_REQUEST:
        /*
         * This could be either a request for a value of a Tcl variable, or it
         * could be the send command requesting the results of the last
         * execute.
         */

        if (uFmt != CF_TEXT) {
            return (HDDEDATA) FALSE;
        }

        ddeReturn = (HDDEDATA) FALSE;
        for (convPtr = tsdPtr->currentConversations; (convPtr != NULL)
                && (convPtr->hConv != hConv); convPtr = convPtr->nextPtr) {
            /*
             * Empty loop body.
             */
        }

        if (convPtr != NULL) {
            char *returnString;

            len = DdeQueryString(ddeInstance, ddeItem, NULL, 0, CP_WINANSI);
            Tcl_DStringInit(&dString);
            Tcl_DStringSetLength(&dString, len);
            utilString = Tcl_DStringValue(&dString);
            DdeQueryString(ddeInstance, ddeItem, utilString, (DWORD) len + 1,
                    CP_WINANSI);
            if (stricmp(utilString, TCL_DDE_EXECUTE_RESULT) == 0) {
                returnString =
                        Tcl_GetStringFromObj(convPtr->returnPackagePtr, &len);
                ddeReturn = DdeCreateDataHandle(ddeInstance, returnString,
                        (DWORD) len+1, 0, ddeItem, CF_TEXT, 0);
            } else {
                if (Tcl_IsSafe(convPtr->riPtr->interp)) {
                    ddeReturn = NULL;
                } else {
                    Tcl_Obj *variableObjPtr = Tcl_GetVar2Ex(
                            convPtr->riPtr->interp, utilString, NULL,
                            TCL_GLOBAL_ONLY);
                    if (variableObjPtr != NULL) {
                        returnString = Tcl_GetStringFromObj(variableObjPtr,
                                &len);
                        ddeReturn = DdeCreateDataHandle(ddeInstance,
                                returnString, (DWORD) len+1, 0, ddeItem,
                                CF_TEXT, 0);
                    } else {
                        ddeReturn = NULL;
                    }
                }
            }
            Tcl_DStringFree(&dString);
        }
        return ddeReturn;

    case XTYP_EXECUTE: {
        /*
         * Execute this script. The results will be saved into a list object
         * which will be retreived later. See ExecuteRemoteObject.
         */

        Tcl_Obj *returnPackagePtr;

        for (convPtr = tsdPtr->currentConversations; (convPtr != NULL)
                && (convPtr->hConv != hConv); convPtr = convPtr->nextPtr) {
            /*
             * Empty loop body.
             */
        }

        if (convPtr == NULL) {
            return (HDDEDATA) DDE_FNOTPROCESSED;
        }

        utilString = (char *) DdeAccessData(hData, &dlen);
        len = dlen;
        ddeObjectPtr = Tcl_NewStringObj(utilString, -1);
        Tcl_IncrRefCount(ddeObjectPtr);
        DdeUnaccessData(hData);
        if (convPtr->returnPackagePtr != NULL) {
            Tcl_DecrRefCount(convPtr->returnPackagePtr);
        }
        convPtr->returnPackagePtr = NULL;
        returnPackagePtr = ExecuteRemoteObject(convPtr->riPtr, ddeObjectPtr);
        Tcl_IncrRefCount(returnPackagePtr);
        for (convPtr = tsdPtr->currentConversations; (convPtr != NULL)
                && (convPtr->hConv != hConv); convPtr = convPtr->nextPtr) {
            /*
             * Empty loop body.
             */
        }
        if (convPtr != NULL) {
            convPtr->returnPackagePtr = returnPackagePtr;
        } else {
            Tcl_DecrRefCount(returnPackagePtr);
        }
        Tcl_DecrRefCount(ddeObjectPtr);
        if (returnPackagePtr == NULL) {
            return (HDDEDATA) DDE_FNOTPROCESSED;
        } else {
            return (HDDEDATA) DDE_FACK;
        }
    }

    case XTYP_WILDCONNECT: {
        /*
         * Dde wants a list of services and topics that we support.
         */

        HSZPAIR *returnPtr;
        int i;
        int numItems;

        for (i = 0, riPtr = tsdPtr->interpListPtr; riPtr != NULL;
                i++, riPtr = riPtr->nextPtr) {
            /*
             * Empty loop body.
             */
        }

        numItems = i;
        ddeReturn = DdeCreateDataHandle(ddeInstance, NULL,
                (numItems + 1) * sizeof(HSZPAIR), 0, 0, 0, 0);
        returnPtr = (HSZPAIR *) DdeAccessData(ddeReturn, &dlen);
        len = dlen;
        for (i = 0, riPtr = tsdPtr->interpListPtr; i < numItems;
                i++, riPtr = riPtr->nextPtr) {
            returnPtr[i].hszSvc = DdeCreateStringHandle(ddeInstance,
                    TCL_DDE_SERVICE_NAME, CP_WINANSI);
            returnPtr[i].hszTopic = DdeCreateStringHandle(ddeInstance,
                    riPtr->name, CP_WINANSI);
        }
        returnPtr[i].hszSvc = NULL;
        returnPtr[i].hszTopic = NULL;
        DdeUnaccessData(ddeReturn);
        return ddeReturn;
    }

    default:
        return NULL;
    }
}

/*
 *----------------------------------------------------------------------
 *
 * DdeExitProc --
 *
 *      Gets rid of our DDE server when we go away.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The DDE server is deleted.
 *
 *----------------------------------------------------------------------
 */

static void
DdeExitProc(
    ClientData clientData)          /* Not used in this handler. */
{
    DdeNameService(ddeInstance, NULL, 0, DNS_UNREGISTER);
    DdeUninitialize(ddeInstance);
    ddeInstance = 0;
}

/*
 *----------------------------------------------------------------------
 *
 * MakeDdeConnection --
 *
 *      This function is a utility used to connect to a DDE server when given
 *      a server name and a topic name.
 *
 * Results:
 *      A standard Tcl result.
 *
 * Side effects:
 *      Passes back a conversation through ddeConvPtr
 *
 *----------------------------------------------------------------------
 */

static int
MakeDdeConnection(
    Tcl_Interp *interp,         /* Used to report errors. */
    char *name,                 /* The connection to use. */
    HCONV *ddeConvPtr)
{
    HSZ ddeTopic, ddeService;
    HCONV ddeConv;

    ddeService = DdeCreateStringHandle(ddeInstance, TCL_DDE_SERVICE_NAME, 0);
    ddeTopic = DdeCreateStringHandle(ddeInstance, name, 0);

    ddeConv = DdeConnect(ddeInstance, ddeService, ddeTopic, NULL);
    DdeFreeStringHandle(ddeInstance, ddeService);
    DdeFreeStringHandle(ddeInstance, ddeTopic);

    if (ddeConv == (HCONV) NULL) {
        if (interp != NULL) {
            Tcl_AppendResult(interp, "no registered server named \"",
                    name, "\"", NULL);
        }
        return TCL_ERROR;
    }

    *ddeConvPtr = ddeConv;
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * DdeGetServicesList --
 *
 *      This function obtains the list of DDE services.
 *
 *      The functions between here and this function are all involved with
 *      handling the DDE callbacks for this. They are: DdeCreateClient,
 *      DdeClientWindowProc, DdeServicesOnAck, and DdeEnumWindowsCallback
 *
 * Results:
 *      A standard Tcl result.
 *
 * Side effects:
 *      Sets the services list into the interp result.
 *
 *----------------------------------------------------------------------
 */

static int
DdeCreateClient(
    struct DdeEnumServices *es)
{
    WNDCLASSEX wc;
    static const char *szDdeClientClassName = "TclEval client class";
    static const char *szDdeClientWindowName = "TclEval client window";

    memset(&wc, 0, sizeof(wc));
    wc.cbSize = sizeof(wc);
    wc.lpfnWndProc = DdeClientWindowProc;
    wc.lpszClassName = szDdeClientClassName;
    wc.cbWndExtra = sizeof(struct DdeEnumServices *);

    /*
     * Register and create the callback window.
     */

    RegisterClassEx(&wc);
    es->hwnd = CreateWindowEx(0, szDdeClientClassName, szDdeClientWindowName,
            WS_POPUP, 0, 0, 0, 0, NULL, NULL, NULL, (LPVOID)es);
    return TCL_OK;
}

static LRESULT CALLBACK
DdeClientWindowProc(
    HWND hwnd,                  /* What window is the message for */
    UINT uMsg,                  /* The type of message received */
    WPARAM wParam,
    LPARAM lParam)              /* (Potentially) our local handle */
{

    switch (uMsg) {
    case WM_CREATE: {
        LPCREATESTRUCT lpcs = (LPCREATESTRUCT) lParam;
        struct DdeEnumServices *es =
                (struct DdeEnumServices *) lpcs->lpCreateParams;

#ifdef _WIN64
        SetWindowLongPtr(hwnd, GWLP_USERDATA, (long)es);
#else
        SetWindowLong(hwnd, GWL_USERDATA, (long)es);
#endif
        return (LRESULT) 0L;
    }
    case WM_DDE_ACK:
        return DdeServicesOnAck(hwnd, wParam, lParam);
        break;
    default:
        return DefWindowProc(hwnd, uMsg, wParam, lParam);
    }
}

static LRESULT
DdeServicesOnAck(
    HWND hwnd,
    WPARAM wParam,
    LPARAM lParam)
{
    HWND hwndRemote = (HWND)wParam;
    ATOM service = (ATOM)LOWORD(lParam);
    ATOM topic = (ATOM)HIWORD(lParam);
    struct DdeEnumServices *es;
    TCHAR sz[255];

#ifdef _WIN64
    es = (struct DdeEnumServices *) GetWindowLongPtr(hwnd, GWLP_USERDATA);
#else
    es = (struct DdeEnumServices *) GetWindowLong(hwnd, GWL_USERDATA);
#endif

    if ((es->service == (ATOM)NULL || es->service == service)
            && (es->topic == (ATOM)NULL || es->topic == topic)) {
        Tcl_Obj *matchPtr = Tcl_NewListObj(0, NULL);
        Tcl_Obj *resultPtr = Tcl_GetObjResult(es->interp);

        GlobalGetAtomName(service, sz, 255);
        Tcl_ListObjAppendElement(NULL, matchPtr, Tcl_NewStringObj(sz, -1));
        GlobalGetAtomName(topic, sz, 255);
        Tcl_ListObjAppendElement(NULL, matchPtr, Tcl_NewStringObj(sz, -1));

        /*
         * Adding the hwnd as a third list element provides a unique
         * identifier in the case of multiple servers with the name
         * application and topic names.
         */
        /*
         * Needs a TIP though:
         * Tcl_ListObjAppendElement(NULL, matchPtr,
         *      Tcl_NewLongObj((long)hwndRemote));
         */

        if (Tcl_IsShared(resultPtr)) {
            resultPtr = Tcl_DuplicateObj(resultPtr);
        }
        if (Tcl_ListObjAppendElement(es->interp, resultPtr,
                matchPtr) == TCL_OK) {
            Tcl_SetObjResult(es->interp, resultPtr);
        }
    }

    /*
     * Tell the server we are no longer interested.
     */

    PostMessage(hwndRemote, WM_DDE_TERMINATE, (WPARAM)hwnd, 0L);
    return 0L;
}

static BOOL CALLBACK
DdeEnumWindowsCallback(
    HWND hwndTarget,
    LPARAM lParam)
{
    LRESULT dwResult = 0;
    struct DdeEnumServices *es = (struct DdeEnumServices *) lParam;

    SendMessageTimeout(hwndTarget, WM_DDE_INITIATE, (WPARAM)es->hwnd,
            MAKELONG(es->service, es->topic), SMTO_ABORTIFHUNG, 1000,
            &dwResult);
    return TRUE;
}

static int
DdeGetServicesList(
    Tcl_Interp *interp,
    char *serviceName,
    char *topicName)
{
    struct DdeEnumServices es;

    es.interp = interp;
    es.result = TCL_OK;
    es.service = (serviceName == NULL)
            ? (ATOM)NULL : GlobalAddAtom(serviceName);
    es.topic = (topicName == NULL) ? (ATOM)NULL : GlobalAddAtom(topicName);

    Tcl_ResetResult(interp); /* our list is to be appended to result. */
    DdeCreateClient(&es);
    EnumWindows(DdeEnumWindowsCallback, (LPARAM)&es);

    if (IsWindow(es.hwnd)) {
        DestroyWindow(es.hwnd);
    }
    if (es.service != (ATOM)NULL) {
        GlobalDeleteAtom(es.service);
    }
    if (es.topic != (ATOM)NULL) {
        GlobalDeleteAtom(es.topic);
    }
    return es.result;
}

/*
 *----------------------------------------------------------------------
 *
 * SetDdeError --
 *
 *      Sets the interp result to a cogent error message describing the last
 *      DDE error.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The interp's result object is changed.
 *
 *----------------------------------------------------------------------
 */

static void
SetDdeError(
    Tcl_Interp *interp)     /* The interp to put the message in. */
{
    char *errorMessage;

    switch (DdeGetLastError(ddeInstance)) {
    case DMLERR_DATAACKTIMEOUT:
    case DMLERR_EXECACKTIMEOUT:
    case DMLERR_POKEACKTIMEOUT:
        errorMessage = "remote interpreter did not respond";
        break;
    case DMLERR_BUSY:
        errorMessage = "remote server is busy";
        break;
    case DMLERR_NOTPROCESSED:
        errorMessage = "remote server cannot handle this command";
        break;
    default:
        errorMessage = "dde command failed";
    }

    Tcl_SetObjResult(interp, Tcl_NewStringObj(errorMessage, -1));
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_DdeObjCmd --
 *
 *      This function is invoked to process the "dde" Tcl command. See the
 *      user documentation for details on what it does.
 *
 * Results:
 *      A standard Tcl result.
 *
 * Side effects:
 *      See the user documentation.
 *
 *----------------------------------------------------------------------
 */

int
Tcl_DdeObjCmd(
    ClientData clientData,      /* Used only for deletion */
    Tcl_Interp *interp,         /* The interp we are sending from */
    int objc,                   /* Number of arguments */
    Tcl_Obj *CONST * objv)      /* The arguments */
{
    static CONST char *ddeCommands[] = {
        "servername", "execute", "poke", "request", "services", "eval",
        (char *) NULL
    };
    enum DdeSubcommands {
        DDE_SERVERNAME, DDE_EXECUTE, DDE_POKE, DDE_REQUEST, DDE_SERVICES,
        DDE_EVAL
    };
    static CONST char *ddeSrvOptions[] = {
        "-force", "-handler", "--", NULL
    };
    enum DdeSrvOptions {
        DDE_SERVERNAME_EXACT, DDE_SERVERNAME_HANDLER, DDE_SERVERNAME_LAST,
    };
    static CONST char *ddeExecOptions[] = {
        "-async", NULL
    };
    static CONST char *ddeReqOptions[] = {
        "-binary", NULL
    };

    int index, i, length;
    int async = 0, binary = 0, exact = 0;
    int result = TCL_OK, firstArg = 0;
    HSZ ddeService = NULL, ddeTopic = NULL, ddeItem = NULL, ddeCookie = NULL;
    HDDEDATA ddeData = NULL, ddeItemData = NULL, ddeReturn;
    HCONV hConv = NULL;
    char *serviceName = NULL, *topicName = NULL, *string;
    DWORD ddeResult;
    Tcl_Obj *objPtr, *handlerPtr = NULL;

    /*
     * Initialize DDE server/client
     */

    if (objc < 2) {
        Tcl_WrongNumArgs(interp, 1, objv, "command ?arg ...?");
        return TCL_ERROR;
    }

    if (Tcl_GetIndexFromObj(interp, objv[1], ddeCommands, "command", 0,
            &index) != TCL_OK) {
        return TCL_ERROR;
    }

    switch ((enum DdeSubcommands) index) {
    case DDE_SERVERNAME:
        for (i = 2; i < objc; i++) {
            int argIndex;
            if (Tcl_GetIndexFromObj(interp, objv[i], ddeSrvOptions,
                    "option", 0, &argIndex) != TCL_OK) {
                /*
                 * If it is the last argument, it might be a server name
                 * instead of a bad argument.
                 */

                if (i != objc-1) {
                    return TCL_ERROR;
                }
                Tcl_ResetResult(interp);
                break;
            }
            if (argIndex == DDE_SERVERNAME_EXACT) {
                exact = 1;
            } else if (argIndex == DDE_SERVERNAME_HANDLER) {
                if ((objc - i) == 1) {  /* return current handler */
                    RegisteredInterp *riPtr = DdeGetRegistrationPtr(interp);

                    if (riPtr && riPtr->handlerPtr) {
                        Tcl_SetObjResult(interp, riPtr->handlerPtr);
                    } else {
                        Tcl_ResetResult(interp);
                    }
                    return TCL_OK;
                }
                handlerPtr = objv[++i];
            } else if (argIndex == DDE_SERVERNAME_LAST) {
                i++;
                break;
            }
        }

        if ((objc - i) > 1) {
            Tcl_ResetResult(interp);
            Tcl_WrongNumArgs(interp, 2, objv,
                    "?-force? ?-handler proc? ?--? ?serverName?");
            return TCL_ERROR;
        }

        firstArg = (objc == i) ? 1 : i;
        break;
    case DDE_EXECUTE:
        if (objc == 5) {
            firstArg = 2;
            break;
        } else if (objc == 6) {
            int dummy;
            if (Tcl_GetIndexFromObj(NULL, objv[2], ddeExecOptions, "option", 0,
                    &dummy) == TCL_OK) {
                async = 1;
                firstArg = 3;
                break;
            }
        }
        /* otherwise... */
        Tcl_WrongNumArgs(interp, 2, objv,
                "?-async? serviceName topicName value");
        return TCL_ERROR;
    case DDE_POKE:
        if (objc != 6) {
            Tcl_WrongNumArgs(interp, 2, objv,
                    "serviceName topicName item value");
            return TCL_ERROR;
        }
        firstArg = 2;
        break;
    case DDE_REQUEST:
        if (objc == 5) {
            firstArg = 2;
            break;
        } else if (objc == 6) {
            int dummy;
            if (Tcl_GetIndexFromObj(NULL, objv[2], ddeReqOptions, "option", 0,
                    &dummy) == TCL_OK) {
                binary = 1;
                firstArg = 3;
                break;
            }
        }

        /*
         * Otherwise ...
         */

        Tcl_WrongNumArgs(interp, 2, objv,
                "?-binary? serviceName topicName value");
        return TCL_ERROR;
    case DDE_SERVICES:
        if (objc != 4) {
            Tcl_WrongNumArgs(interp, 2, objv, "serviceName topicName");
            return TCL_ERROR;
        }
        firstArg = 2;
        break;
    case DDE_EVAL:
        if (objc < 4) {
        wrongDdeEvalArgs:
            Tcl_WrongNumArgs(interp, 2, objv, "?-async? serviceName args");
            return TCL_ERROR;
        } else {
            int dummy;

            firstArg = 2;
            if (Tcl_GetIndexFromObj(NULL, objv[2], ddeExecOptions, "option", 0,
                    &dummy) == TCL_OK) {
                if (objc < 5) {
                    goto wrongDdeEvalArgs;
                }
                async = 1;
                firstArg++;
            }
            break;
        }
    }

    Initialize();

    if (firstArg != 1) {
        serviceName = Tcl_GetStringFromObj(objv[firstArg], &length);
    } else {
        length = 0;
    }

    if (length == 0) {
        serviceName = NULL;
    } else if ((index != DDE_SERVERNAME) && (index != DDE_EVAL)) {
        ddeService = DdeCreateStringHandle(ddeInstance, serviceName,
                CP_WINANSI);
    }

    if ((index != DDE_SERVERNAME) && (index != DDE_EVAL)) {
        topicName = Tcl_GetStringFromObj(objv[firstArg + 1], &length);
        if (length == 0) {
            topicName = NULL;
        } else {
            ddeTopic = DdeCreateStringHandle(ddeInstance, topicName,
                    CP_WINANSI);
        }
    }

    switch ((enum DdeSubcommands) index) {
    case DDE_SERVERNAME:
        serviceName = DdeSetServerName(interp, serviceName, exact, handlerPtr);
        if (serviceName != NULL) {
            Tcl_SetObjResult(interp, Tcl_NewStringObj(serviceName, -1));
        } else {
            Tcl_ResetResult(interp);
        }
        break;

    case DDE_EXECUTE: {
        int dataLength;
        char *dataString = Tcl_GetStringFromObj(objv[firstArg + 2],
                &dataLength);

        if (dataLength == 0) {
            Tcl_SetObjResult(interp,
                    Tcl_NewStringObj("cannot execute null data", -1));
            result = TCL_ERROR;
            break;
        }
        hConv = DdeConnect(ddeInstance, ddeService, ddeTopic, NULL);
        DdeFreeStringHandle(ddeInstance, ddeService);
        DdeFreeStringHandle(ddeInstance, ddeTopic);

        if (hConv == NULL) {
            SetDdeError(interp);
            result = TCL_ERROR;
            break;
        }

        ddeData = DdeCreateDataHandle(ddeInstance, dataString,
                (DWORD) dataLength+1, 0, 0, CF_TEXT, 0);
        if (ddeData != NULL) {
            if (async) {
                DdeClientTransaction((LPBYTE) ddeData, 0xFFFFFFFF, hConv, 0,
                        CF_TEXT, XTYP_EXECUTE, TIMEOUT_ASYNC, &ddeResult);
                DdeAbandonTransaction(ddeInstance, hConv, ddeResult);
            } else {
                ddeReturn = DdeClientTransaction((LPBYTE) ddeData, 0xFFFFFFFF,
                        hConv, 0, CF_TEXT, XTYP_EXECUTE, 30000, NULL);
                if (ddeReturn == 0) {
                    SetDdeError(interp);
                    result = TCL_ERROR;
                }
            }
            DdeFreeDataHandle(ddeData);
        } else {
            SetDdeError(interp);
            result = TCL_ERROR;
        }
        break;
    }
    case DDE_REQUEST: {
        char *itemString = Tcl_GetStringFromObj(objv[firstArg + 2], &length);

        if (length == 0) {
            Tcl_SetObjResult(interp,
                    Tcl_NewStringObj("cannot request value of null data", -1));
            result = TCL_ERROR;
            goto cleanup;
        }
        hConv = DdeConnect(ddeInstance, ddeService, ddeTopic, NULL);
        DdeFreeStringHandle(ddeInstance, ddeService);
        DdeFreeStringHandle(ddeInstance, ddeTopic);

        if (hConv == NULL) {
            SetDdeError(interp);
            result = TCL_ERROR;
        } else {
            Tcl_Obj *returnObjPtr;
            ddeItem = DdeCreateStringHandle(ddeInstance, itemString,
                    CP_WINANSI);
            if (ddeItem != NULL) {
                ddeData = DdeClientTransaction(NULL, 0, hConv, ddeItem,
                        CF_TEXT, XTYP_REQUEST, 5000, NULL);
                if (ddeData == NULL) {
                    SetDdeError(interp);
                    result = TCL_ERROR;
                } else {
                    DWORD tmp;
                    char *dataString = DdeAccessData(ddeData, &tmp);

                    if (binary) {
                        returnObjPtr = Tcl_NewByteArrayObj(dataString,
                                (int) tmp);
                    } else {
                        returnObjPtr = Tcl_NewStringObj(dataString, -1);
                    }
                    DdeUnaccessData(ddeData);
                    DdeFreeDataHandle(ddeData);
                    Tcl_SetObjResult(interp, returnObjPtr);
                }
            } else {
                SetDdeError(interp);
                result = TCL_ERROR;
            }
        }

        break;
    }
    case DDE_POKE: {
        char *itemString = Tcl_GetStringFromObj(objv[firstArg + 2], &length);
        char *dataString;

        if (length == 0) {
            Tcl_SetObjResult(interp,
                    Tcl_NewStringObj("cannot have a null item", -1));
            result = TCL_ERROR;
            goto cleanup;
        }
        dataString = Tcl_GetStringFromObj(objv[firstArg + 3], &length);

        hConv = DdeConnect(ddeInstance, ddeService, ddeTopic, NULL);
        DdeFreeStringHandle(ddeInstance, ddeService);
        DdeFreeStringHandle(ddeInstance, ddeTopic);

        if (hConv == NULL) {
            SetDdeError(interp);
            result = TCL_ERROR;
        } else {
            ddeItem = DdeCreateStringHandle(ddeInstance, itemString,
                    CP_WINANSI);
            if (ddeItem != NULL) {
                ddeData = DdeClientTransaction(dataString, (DWORD) length+1,
                        hConv, ddeItem, CF_TEXT, XTYP_POKE, 5000, NULL);
                if (ddeData == NULL) {
                    SetDdeError(interp);
                    result = TCL_ERROR;
                }
            } else {
                SetDdeError(interp);
                result = TCL_ERROR;
            }
        }
        break;
    }

    case DDE_SERVICES:
        result = DdeGetServicesList(interp, serviceName, topicName);
        break;

    case DDE_EVAL: {
        RegisteredInterp *riPtr;
        ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

        if (serviceName == NULL) {
            Tcl_SetObjResult(interp,
                    Tcl_NewStringObj("invalid service name \"\"", -1));
            result = TCL_ERROR;
            goto cleanup;
        }

        objc -= (async + 3);
        objv += (async + 3);

        /*
         * See if the target interpreter is local. If so, execute the command
         * directly without going through the DDE server. Don't exchange
         * objects between interps. The target interp could compile an object,
         * producing a bytecode structure that refers to other objects owned
         * by the target interp. If the target interp is then deleted, the
         * bytecode structure would be referring to deallocated objects.
         */

        for (riPtr = tsdPtr->interpListPtr; riPtr != NULL;
                riPtr = riPtr->nextPtr) {
            if (stricmp(serviceName, riPtr->name) == 0) {
                break;
            }
        }

        if (riPtr != NULL) {
            Tcl_Interp *sendInterp;

            /*
             * This command is to a local interp. No need to go through the
             * server.
             */

            Tcl_Preserve((ClientData) riPtr);
            sendInterp = riPtr->interp;
            Tcl_Preserve((ClientData) sendInterp);

            /*
             * Don't exchange objects between interps. The target interp would
             * compile an object, producing a bytecode structure that refers
             * to other objects owned by the target interp. If the target
             * interp is then deleted, the bytecode structure would be
             * referring to deallocated objects.
             */

            if (Tcl_IsSafe(riPtr->interp) && riPtr->handlerPtr == NULL) {
                Tcl_SetResult(riPtr->interp, "permission denied: "
                        "a handler procedure must be defined for use in "
                        "a safe interp", TCL_STATIC);
                result = TCL_ERROR;
            }

            if (result == TCL_OK) {
                if (objc == 1)
                    objPtr = objv[0];
                else {
                    objPtr = Tcl_ConcatObj(objc, objv);
                }
                if (riPtr->handlerPtr != NULL) {
                    /* add the dde request data to the handler proc list */
                    /*
                     *result = Tcl_ListObjReplace(sendInterp, objPtr, 0, 0, 1,
                     *      &(riPtr->handlerPtr));
                     */
                    Tcl_Obj *cmdPtr = Tcl_DuplicateObj(riPtr->handlerPtr);
                    result = Tcl_ListObjAppendElement(sendInterp, cmdPtr,
                            objPtr);
                    if (result == TCL_OK) {
                        objPtr = cmdPtr;
                    }
                }
            }
            if (result == TCL_OK) {
                Tcl_IncrRefCount(objPtr);
                result = Tcl_EvalObjEx(sendInterp, objPtr, TCL_EVAL_GLOBAL);
                Tcl_DecrRefCount(objPtr);
            }
            if (interp != sendInterp) {
                if (result == TCL_ERROR) {
                    /*
                     * An error occurred, so transfer error information from
                     * the destination interpreter back to our interpreter.
                     */

                    Tcl_ResetResult(interp);
                    objPtr = Tcl_GetVar2Ex(sendInterp, "errorInfo", NULL,
                            TCL_GLOBAL_ONLY);
                    if (objPtr) {
                        string = Tcl_GetStringFromObj(objPtr, &length);
                        Tcl_AddObjErrorInfo(interp, string, length);
                    }

                    objPtr = Tcl_GetVar2Ex(sendInterp, "errorCode", NULL,
                            TCL_GLOBAL_ONLY);
                    if (objPtr) {
                        Tcl_SetObjErrorCode(interp, objPtr);
                    }
                }
                Tcl_SetObjResult(interp, Tcl_GetObjResult(sendInterp));
            }
            Tcl_Release((ClientData) riPtr);
            Tcl_Release((ClientData) sendInterp);
        } else {
            /*
             * This is a non-local request. Send the script to the server and
             * poll it for a result.
             */

            if (MakeDdeConnection(interp, serviceName, &hConv) != TCL_OK) {
            invalidServerResponse:
                Tcl_SetObjResult(interp,
                        Tcl_NewStringObj("invalid data returned from server",
                        -1));
                result = TCL_ERROR;
                goto cleanup;
            }

            objPtr = Tcl_ConcatObj(objc, objv);
            string = Tcl_GetStringFromObj(objPtr, &length);
            ddeItemData = DdeCreateDataHandle(ddeInstance, string,
                    (DWORD) length+1, 0, 0, CF_TEXT, 0);

            if (async) {
                ddeData = DdeClientTransaction((LPBYTE) ddeItemData,
                        0xFFFFFFFF, hConv, 0,
                        CF_TEXT, XTYP_EXECUTE, TIMEOUT_ASYNC, &ddeResult);
                DdeAbandonTransaction(ddeInstance, hConv, ddeResult);
            } else {
                ddeData = DdeClientTransaction((LPBYTE) ddeItemData,
                        0xFFFFFFFF, hConv, 0,
                        CF_TEXT, XTYP_EXECUTE, 30000, NULL);
                if (ddeData != 0) {
                    ddeCookie = DdeCreateStringHandle(ddeInstance,
                            TCL_DDE_EXECUTE_RESULT, CP_WINANSI);
                    ddeData = DdeClientTransaction(NULL, 0, hConv, ddeCookie,
                            CF_TEXT, XTYP_REQUEST, 30000, NULL);
                }
            }

            Tcl_DecrRefCount(objPtr);

            if (ddeData == 0) {
                SetDdeError(interp);
                result = TCL_ERROR;
            }

            if (async == 0) {
                Tcl_Obj *resultPtr;

                /*
                 * The return handle has a two or four element list in it. The
                 * first element is the return code (TCL_OK, TCL_ERROR, etc.).
                 * The second is the result of the script. If the return code
                 * is TCL_ERROR, then the third element is the value of the
                 * variable "errorCode", and the fourth is the value of the
                 * variable "errorInfo".
                 */

                resultPtr = Tcl_NewObj();
                length = DdeGetData(ddeData, NULL, 0, 0);
                Tcl_SetObjLength(resultPtr, length);
                string = Tcl_GetString(resultPtr);
                DdeGetData(ddeData, string, (DWORD) length, 0);
                Tcl_SetObjLength(resultPtr, (int) strlen(string));

                if (Tcl_ListObjIndex(NULL, resultPtr, 0, &objPtr) != TCL_OK) {
                    Tcl_DecrRefCount(resultPtr);
                    goto invalidServerResponse;
                }
                if (Tcl_GetIntFromObj(NULL, objPtr, &result) != TCL_OK) {
                    Tcl_DecrRefCount(resultPtr);
                    goto invalidServerResponse;
                }
                if (result == TCL_ERROR) {
                    Tcl_ResetResult(interp);

                    if (Tcl_ListObjIndex(NULL, resultPtr, 3,
                            &objPtr) != TCL_OK) {
                        Tcl_DecrRefCount(resultPtr);
                        goto invalidServerResponse;
                    }
                    length = -1;
                    string = Tcl_GetStringFromObj(objPtr, &length);
                    Tcl_AddObjErrorInfo(interp, string, length);

                    Tcl_ListObjIndex(NULL, resultPtr, 2, &objPtr);
                    Tcl_SetObjErrorCode(interp, objPtr);
                }
                if (Tcl_ListObjIndex(NULL, resultPtr, 1, &objPtr) != TCL_OK) {
                    Tcl_DecrRefCount(resultPtr);
                    goto invalidServerResponse;
                }
                Tcl_SetObjResult(interp, objPtr);
                Tcl_DecrRefCount(resultPtr);
            }
        }
    }
    }

  cleanup:
    if (ddeCookie != NULL) {
        DdeFreeStringHandle(ddeInstance, ddeCookie);
    }
    if (ddeItem != NULL) {
        DdeFreeStringHandle(ddeInstance, ddeItem);
    }
    if (ddeItemData != NULL) {
        DdeFreeDataHandle(ddeItemData);
    }
    if (ddeData != NULL) {
        DdeFreeDataHandle(ddeData);
    }
    if (hConv != NULL) {
        DdeDisconnect(hConv);
    }
    return result;
}

/*
 * Local variables:
 * mode: c
 * indent-tabs-mode: t
 * tab-width: 8
 * c-basic-offset: 4
 * fill-column: 78
 * End:
 */