The Tor Browser: gfx/angle/src/compiler/DetectCallDepth.cpp@97036ab72558 (annotated)

gfx/angle/src/compiler/DetectCallDepth.cpp@97036ab72558 (annotated)

gfx/angle/src/compiler/DetectCallDepth.cpp

Tue, 06 Jan 2015 21:39:09 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Tue, 06 Jan 2015 21:39:09 +0100
branch: TOR_BUG_9701
changeset 8: 97036ab72558
permissions: -rw-r--r--

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.

 //
 // Copyright (c) 2002-2011 The ANGLE Project Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 #include "compiler/DetectCallDepth.h"
 #include "compiler/InfoSink.h"
 DetectCallDepth::FunctionNode::FunctionNode(const TString& fname)
     : name(fname),
       visit(PreVisit)
 {
 }
 const TString& DetectCallDepth::FunctionNode::getName() const
 {
     return name;
 }
 void DetectCallDepth::FunctionNode::addCallee(
     DetectCallDepth::FunctionNode* callee)
 {
     for (size_t i = 0; i < callees.size(); ++i) {
         if (callees[i] == callee)
             return;
     }
     callees.push_back(callee);
 }
 int DetectCallDepth::FunctionNode::detectCallDepth(DetectCallDepth* detectCallDepth, int depth)
 {
     ASSERT(visit == PreVisit);
     ASSERT(detectCallDepth);
     int maxDepth = depth;
     visit = InVisit;
     for (size_t i = 0; i < callees.size(); ++i) {
         switch (callees[i]->visit) {
             case InVisit:
                 // cycle detected, i.e., recursion detected.
                 return kInfiniteCallDepth;
             case PostVisit:
                 break;
             case PreVisit: {
                 // Check before we recurse so we don't go too depth
                 if (detectCallDepth->checkExceedsMaxDepth(depth))
                     return depth;
                 int callDepth = callees[i]->detectCallDepth(detectCallDepth, depth + 1);
                 // Check after we recurse so we can exit immediately and provide info.
                 if (detectCallDepth->checkExceedsMaxDepth(callDepth)) {
                     detectCallDepth->getInfoSink().info << "<-" << callees[i]->getName();
                     return callDepth;
                 }
                 maxDepth = std::max(callDepth, maxDepth);
                 break;
             }
             default:
                 UNREACHABLE();
                 break;
         }
     }
     visit = PostVisit;
     return maxDepth;
 }
 void DetectCallDepth::FunctionNode::reset()
 {
     visit = PreVisit;
 }
 DetectCallDepth::DetectCallDepth(TInfoSink& infoSink, bool limitCallStackDepth, int maxCallStackDepth)
     : TIntermTraverser(true, false, true, false),
       currentFunction(NULL),
       infoSink(infoSink),
       maxDepth(limitCallStackDepth ? maxCallStackDepth : FunctionNode::kInfiniteCallDepth)
 {
 }
 DetectCallDepth::~DetectCallDepth()
 {
     for (size_t i = 0; i < functions.size(); ++i)
         delete functions[i];
 }
 bool DetectCallDepth::visitAggregate(Visit visit, TIntermAggregate* node)
 {
     switch (node->getOp())
     {
         case EOpPrototype:
             // Function declaration.
             // Don't add FunctionNode here because node->getName() is the
             // unmangled function name.
             break;
         case EOpFunction: {
             // Function definition.
             if (visit == PreVisit) {
                 currentFunction = findFunctionByName(node->getName());
                 if (currentFunction == NULL) {
                     currentFunction = new FunctionNode(node->getName());
                     functions.push_back(currentFunction);
                 }
             } else if (visit == PostVisit) {
                 currentFunction = NULL;
             }
             break;
         }
         case EOpFunctionCall: {
             // Function call.
             if (visit == PreVisit) {
                 FunctionNode* func = findFunctionByName(node->getName());
                 if (func == NULL) {
                     func = new FunctionNode(node->getName());
                     functions.push_back(func);
                 }
                 if (currentFunction)
                     currentFunction->addCallee(func);
             }
             break;
         }
         default:
             break;
     }
     return true;
 }
 bool DetectCallDepth::checkExceedsMaxDepth(int depth)
 {
     return depth >= maxDepth;
 }
 void DetectCallDepth::resetFunctionNodes()
 {
     for (size_t i = 0; i < functions.size(); ++i) {
         functions[i]->reset();
     }
 }
 DetectCallDepth::ErrorCode DetectCallDepth::detectCallDepthForFunction(FunctionNode* func)
 {
     currentFunction = NULL;
     resetFunctionNodes();
     int maxCallDepth = func->detectCallDepth(this, 1);
     if (maxCallDepth == FunctionNode::kInfiniteCallDepth)
         return kErrorRecursion;
     if (maxCallDepth >= maxDepth)
         return kErrorMaxDepthExceeded;
     return kErrorNone;
 }
 DetectCallDepth::ErrorCode DetectCallDepth::detectCallDepth()
 {
     if (maxDepth != FunctionNode::kInfiniteCallDepth) {
         // Check all functions because the driver may fail on them
         // TODO: Before detectingRecursion, strip unused functions.
         for (size_t i = 0; i < functions.size(); ++i) {
             ErrorCode error = detectCallDepthForFunction(functions[i]);
             if (error != kErrorNone)
                 return error;
         }
     } else {
         FunctionNode* main = findFunctionByName("main(");
         if (main == NULL)
             return kErrorMissingMain;
         return detectCallDepthForFunction(main);
     }
     return kErrorNone;
 }
 DetectCallDepth::FunctionNode* DetectCallDepth::findFunctionByName(
     const TString& name)
 {
     for (size_t i = 0; i < functions.size(); ++i) {
         if (functions[i]->getName() == name)
             return functions[i];
     }
     return NULL;
 }

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gfx/angle/src/compiler/DetectCallDepth.cpp@97036ab72558 (annotated)

gfx/angle/src/compiler/DetectCallDepth.cpp