* Copyright (c) 1994-1997 Sun Microsystems, Inc.
 * Copyright (c) 1998-1999 by Scriptics Corporation.
 * Copyright (c) 2001 by Kevin B. Kenny.  All rights reserved.
 *
 * See the file "license.terms" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * RCS: @(#) $Id: tclVar.c,v 1.101 2004/12/14 21:11:47 msofer Exp $
 */

#include "tclInt.h"

/*
 * The strings below are used to indicate what went wrong when a
 * variable access is denied.

Tcl_LappendObjCmd(dummy, interp, objc, objv)
    ClientData dummy;		/* Not used. */
    Tcl_Interp *interp;		/* Current interpreter. */
    int objc;			/* Number of arguments. */
    Tcl_Obj *CONST objv[];	/* Argument objects. */
{
    Tcl_Obj *varValuePtr, *newValuePtr;
    register List *listRepPtr;
    register Tcl_Obj **elemPtrs;
    int numElems, numRequired, createdNewObj, createVar, i, j;
    Var *varPtr, *arrayPtr;
    char *part1;


    if (objc < 2) {
	Tcl_WrongNumArgs(interp, 1, objv, "varName ?value value ...?");
	return TCL_ERROR;
    }
    if (objc == 2) {
	newValuePtr = Tcl_ObjGetVar2(interp, objv[1], (Tcl_Obj *) NULL, 0);

	    varValuePtr = Tcl_NewObj();
	    createdNewObj = 1;
	} else if (Tcl_IsShared(varValuePtr)) {	
	    varValuePtr = Tcl_DuplicateObj(varValuePtr);
	    createdNewObj = 1;
	}

	/*

	 * Convert the variable's old value to a list object if necessary.
	 */



	if (varValuePtr->typePtr != &tclListType) {
	    int result = tclListType.setFromAnyProc(interp, varValuePtr);
	    if (result != TCL_OK) {
		if (createdNewObj) {
		    Tcl_DecrRefCount(varValuePtr); /* free unneeded obj. */
		}
		return result;
	    }
	}
	listRepPtr = (List *) varValuePtr->internalRep.twoPtrValue.ptr1;
	elemPtrs = listRepPtr->elements;
	numElems = listRepPtr->elemCount;

	/*
	 * If there is no room in the current array of element pointers,
	 * allocate a new, larger array and copy the pointers to it.
	 */
	
	numRequired = numElems + (objc-2);
	if (numRequired > listRepPtr->maxElemCount) {
	    int newMax = (2 * numRequired);
	    Tcl_Obj **newElemPtrs = (Tcl_Obj **)
		ckalloc((unsigned) (newMax * sizeof(Tcl_Obj *)));
	    
	    memcpy((VOID *) newElemPtrs, (VOID *) elemPtrs,
		    (size_t) (numElems * sizeof(Tcl_Obj *)));
	    listRepPtr->maxElemCount = newMax;
	    listRepPtr->elements = newElemPtrs;
	    ckfree((char *) elemPtrs);
	    elemPtrs = newElemPtrs;
	}

	/*
	 * Insert the new elements at the end of the list.
	 */

	for (i = 2, j = numElems;  i < objc;  i++, j++) {
            elemPtrs[j] = objv[i];
            Tcl_IncrRefCount(objv[i]);
        }
	listRepPtr->elemCount = numRequired;

	/*
	 * Invalidate and free any old string representation since it no
	 * longer reflects the list's internal representation.
	 */

	Tcl_InvalidateStringRep(varValuePtr);

	/*
	 * Now store the list object back into the variable. If there is an
	 * error setting the new value, decrement its ref count if it
	 * was new and we didn't create the variable.
	 */