The Tor Browser: dom/xslt/xpath/txNumberExpr.cpp@97036ab72558

Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

     1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */

     2 /* This Source Code Form is subject to the terms of the Mozilla Public

     3  * License, v. 2.0. If a copy of the MPL was not distributed with this

     4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

     6 #include "mozilla/FloatingPoint.h"

     8 #include "txExpr.h"

     9 #include <math.h>

    10 #include "txIXPathContext.h"

    12 nsresult

    13 txNumberExpr::evaluate(txIEvalContext* aContext, txAExprResult** aResult)

    14 {

    15     *aResult = nullptr;

    17     nsRefPtr<txAExprResult> exprRes;

    18     nsresult rv = mRightExpr->evaluate(aContext, getter_AddRefs(exprRes));

    19     NS_ENSURE_SUCCESS(rv, rv);

    21     double rightDbl = exprRes->numberValue();

    23     rv = mLeftExpr->evaluate(aContext, getter_AddRefs(exprRes));

    24     NS_ENSURE_SUCCESS(rv, rv);

    26     double leftDbl = exprRes->numberValue();

    27     double result = 0;

    29     switch (mOp) {

    30         case ADD:

    31             result = leftDbl + rightDbl;

    32             break;

    34         case SUBTRACT:

    35             result = leftDbl - rightDbl;

    36             break;

    38         case DIVIDE:

    39             if (rightDbl == 0) {

    40 #if defined(XP_WIN)

    41                 /* XXX MSVC miscompiles such that (NaN == 0) */

    42                 if (mozilla::IsNaN(rightDbl))

    43                     result = mozilla::UnspecifiedNaN<double>();

    44                 else

    45 #endif

    46                 if (leftDbl == 0 || mozilla::IsNaN(leftDbl))

    47                     result = mozilla::UnspecifiedNaN<double>();

    48                 else if (mozilla::IsNegative(leftDbl) != mozilla::IsNegative(rightDbl))

    49                     result = mozilla::NegativeInfinity<double>();

    50                 else

    51                     result = mozilla::PositiveInfinity<double>();

    52             }

    53             else

    54                 result = leftDbl / rightDbl;

    55             break;

    57         case MODULUS:

    58             if (rightDbl == 0) {

    59                 result = mozilla::UnspecifiedNaN<double>();

    60             }

    61             else {

    62 #if defined(XP_WIN)

    63                 /* Workaround MS fmod bug where 42 % (1/0) => NaN, not 42. */

    64                 if (!mozilla::IsInfinite(leftDbl) && mozilla::IsInfinite(rightDbl))

    65                     result = leftDbl;

    66                 else

    67 #endif

    68                 result = fmod(leftDbl, rightDbl);

    69             }

    70             break;

    72         case MULTIPLY:

    73             result = leftDbl * rightDbl;

    74             break;

    75     }

    77     return aContext->recycler()->getNumberResult(result, aResult);

    78 } //-- evaluate

    80 TX_IMPL_EXPR_STUBS_2(txNumberExpr, NUMBER_RESULT, mLeftExpr, mRightExpr)

    82 bool

    83 txNumberExpr::isSensitiveTo(ContextSensitivity aContext)

    84 {

    85     return mLeftExpr->isSensitiveTo(aContext) ||

    86            mRightExpr->isSensitiveTo(aContext);

    87 }

    89 #ifdef TX_TO_STRING

    90 void

    91 txNumberExpr::toString(nsAString& str)

    92 {

    93     mLeftExpr->toString(str);

    95     switch (mOp) {

    96         case ADD:

    97             str.AppendLiteral(" + ");

    98             break;

    99         case SUBTRACT:

   100             str.AppendLiteral(" - ");

   101             break;

   102         case DIVIDE:

   103             str.AppendLiteral(" div ");

   104             break;

   105         case MODULUS:

   106             str.AppendLiteral(" mod ");

   107             break;

   108         case MULTIPLY:

   109             str.AppendLiteral(" * ");

   110             break;

   111     }

   113     mRightExpr->toString(str);

   115 }

   116 #endif

The Tor Browser / file revision

dom/xslt/xpath/txNumberExpr.cpp@97036ab72558

dom/xslt/xpath/txNumberExpr.cpp