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lightning-sunbird  0.9+nobinonly
MultiplicativeExpr.cpp
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00001 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
00002 /* ***** BEGIN LICENSE BLOCK *****
00003  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
00004  *
00005  * The contents of this file are subject to the Mozilla Public License Version
00006  * 1.1 (the "License"); you may not use this file except in compliance with
00007  * the License. You may obtain a copy of the License at
00008  * http://www.mozilla.org/MPL/
00009  *
00010  * Software distributed under the License is distributed on an "AS IS" basis,
00011  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
00012  * for the specific language governing rights and limitations under the
00013  * License.
00014  *
00015  * The Original Code is TransforMiiX XSLT processor code.
00016  *
00017  * The Initial Developer of the Original Code is
00018  * The MITRE Corporation.
00019  * Portions created by the Initial Developer are Copyright (C) 1999
00020  * the Initial Developer. All Rights Reserved.
00021  *
00022  * Contributor(s):
00023  *   Keith Visco <kvisco@ziplink.net> (Original Author)
00024  *
00025  * Alternatively, the contents of this file may be used under the terms of
00026  * either the GNU General Public License Version 2 or later (the "GPL"), or
00027  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
00028  * in which case the provisions of the GPL or the LGPL are applicable instead
00029  * of those above. If you wish to allow use of your version of this file only
00030  * under the terms of either the GPL or the LGPL, and not to allow others to
00031  * use your version of this file under the terms of the MPL, indicate your
00032  * decision by deleting the provisions above and replace them with the notice
00033  * and other provisions required by the GPL or the LGPL. If you do not delete
00034  * the provisions above, a recipient may use your version of this file under
00035  * the terms of any one of the MPL, the GPL or the LGPL.
00036  *
00037  * ***** END LICENSE BLOCK ***** */
00038 
00047 #include "Expr.h"
00048 #include "ExprResult.h"
00049 #include <math.h>
00050 #include "txIXPathContext.h"
00051 
00059 nsresult
00060 MultiplicativeExpr::evaluate(txIEvalContext* aContext, txAExprResult** aResult)
00061 {
00062     *aResult = nsnull;
00063 
00064     nsRefPtr<txAExprResult> exprRes;
00065     nsresult rv = rightExpr->evaluate(aContext, getter_AddRefs(exprRes));
00066     NS_ENSURE_SUCCESS(rv, rv);
00067 
00068     double rightDbl = exprRes->numberValue();
00069 
00070     rv = leftExpr->evaluate(aContext, getter_AddRefs(exprRes));
00071     NS_ENSURE_SUCCESS(rv, rv);
00072 
00073     double leftDbl = exprRes->numberValue();
00074     double result = 0;
00075 
00076     switch ( op ) {
00077         case DIVIDE:
00078             if (rightDbl == 0) {
00079 #if defined(XP_WIN)
00080                 /* XXX MSVC miscompiles such that (NaN == 0) */
00081                 if (Double::isNaN(rightDbl))
00082                     result = Double::NaN;
00083                 else
00084 #endif
00085                 if (leftDbl == 0 || Double::isNaN(leftDbl))
00086                     result = Double::NaN;
00087                 else if (Double::isNeg(leftDbl) ^ Double::isNeg(rightDbl))
00088                     result = Double::NEGATIVE_INFINITY;
00089                 else
00090                     result = Double::POSITIVE_INFINITY;
00091             }
00092             else
00093                 result = leftDbl / rightDbl;
00094             break;
00095         case MODULUS:
00096             if (rightDbl == 0) {
00097                 result = Double::NaN;
00098             }
00099             else {
00100 #if defined(XP_WIN)
00101                 /* Workaround MS fmod bug where 42 % (1/0) => NaN, not 42. */
00102                 if (!Double::isInfinite(leftDbl) && Double::isInfinite(rightDbl))
00103                     result = leftDbl;
00104                 else
00105 #endif
00106                 result = fmod(leftDbl, rightDbl);
00107             }
00108             break;
00109         default:
00110             result = leftDbl * rightDbl;
00111             break;
00112     }
00113 
00114     return aContext->recycler()->getNumberResult(result, aResult);
00115 } //-- evaluate
00116 
00117 #ifdef TX_TO_STRING
00118 void
00119 MultiplicativeExpr::toString(nsAString& str)
00120 {
00121     if ( leftExpr ) leftExpr->toString(str);
00122     else str.AppendLiteral("null");
00123 
00124     switch ( op ) {
00125         case DIVIDE:
00126             str.AppendLiteral(" div ");
00127             break;
00128         case MODULUS:
00129             str.AppendLiteral(" mod ");
00130             break;
00131         default:
00132             str.AppendLiteral(" * ");
00133             break;
00134     }
00135     if ( rightExpr ) rightExpr->toString(str);
00136     else str.AppendLiteral("null");
00137 
00138 }
00139 #endif