/* 

 * tclStubLib.c --

 *

 *	Stub object that will be statically linked into extensions that wish

 *	to access Tcl.

 *

 * Copyright (c) 1998-1999 by Scriptics Corporation.

 * Copyright (c) 1998 Paul Duffin.

 *

 * See the file "license.terms" for information on usage and redistribution

 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.

 *

 * RCS: @(#) $Id: tclStubLib.c,v 1.6.2.1 2005/11/20 18:23:03 jenglish Exp $

 */

/*

 * We need to ensure that we use the stub macros so that this file contains

 * no references to any of the stub functions.  This will make it possible

 * to build an extension that references Tcl_InitStubs but doesn't end up

 * including the rest of the stub functions.

 */

#ifndef USE_TCL_STUBS

#define USE_TCL_STUBS

#endif

#undef USE_TCL_STUB_PROCS

#include "tclInt.h"

#include "tclPort.h"

/*

 * Ensure that Tcl_InitStubs is built as an exported symbol.  The other stub

 * functions should be built as non-exported symbols.

 */

TclStubs *tclStubsPtr = NULL;

TclPlatStubs *tclPlatStubsPtr = NULL;

TclIntStubs *tclIntStubsPtr = NULL;

TclIntPlatStubs *tclIntPlatStubsPtr = NULL;

static TclStubs *	HasStubSupport _ANSI_ARGS_((Tcl_Interp *interp));

static TclStubs *

HasStubSupport (interp)

    Tcl_Interp *interp;

{

    Interp *iPtr = (Interp *) interp;

    if (iPtr->stubTable && (iPtr->stubTable->magic == TCL_STUB_MAGIC)) {

	return iPtr->stubTable;

    }

    interp->result = "This interpreter does not support stubs-enabled extensions.";

    interp->freeProc = TCL_STATIC;

    return NULL;

}

/*

 *----------------------------------------------------------------------

 *

 * Tcl_InitStubs --

 *

 *	Tries to initialise the stub table pointers and ensures that

 *	the correct version of Tcl is loaded.

 *

 * Results:

 *	The actual version of Tcl that satisfies the request, or

 *	NULL to indicate that an error occurred.

 *

 * Side effects:

 *	Sets the stub table pointers.

 *

 *----------------------------------------------------------------------

 */

#ifdef Tcl_InitStubs

#undef Tcl_InitStubs

#endif

CONST char *

Tcl_InitStubs (interp, version, exact)

    Tcl_Interp *interp;

    CONST char *version;

    int exact;

{

    CONST char *actualVersion = NULL;

    ClientData pkgData = NULL;

    /*

     * We can't optimize this check by caching tclStubsPtr because

     * that prevents apps from being able to load/unload Tcl dynamically

     * multiple times. [Bug 615304]

     */

    tclStubsPtr = HasStubSupport(interp);

    if (!tclStubsPtr) {

	return NULL;

    }

    actualVersion = Tcl_PkgRequireEx(interp, "Tcl", version, exact, &pkgData);

    if (actualVersion == NULL) {

	return NULL;

    }

    tclStubsPtr = (TclStubs*)pkgData;

    if (tclStubsPtr->hooks) {

	tclPlatStubsPtr = tclStubsPtr->hooks->tclPlatStubs;

	tclIntStubsPtr = tclStubsPtr->hooks->tclIntStubs;

	tclIntPlatStubsPtr = tclStubsPtr->hooks->tclIntPlatStubs;

    } else {

	tclPlatStubsPtr = NULL;

	tclIntStubsPtr = NULL;

	tclIntPlatStubsPtr = NULL;

    }

    return actualVersion;

}