michael@0: /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* vim: set ts=8 sts=2 et sw=2 tw=80: */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "nsWrapperCacheInlines.h"
michael@0: 
michael@0: #include "jsproxy.h"
michael@0: #include "mozilla/dom/DOMJSProxyHandler.h"
michael@0: #include "mozilla/HoldDropJSObjects.h"
michael@0: #include "nsCycleCollectionTraversalCallback.h"
michael@0: #include "nsCycleCollector.h"
michael@0: 
michael@0: using namespace mozilla;
michael@0: using namespace mozilla::dom;
michael@0: 
michael@0: /* static */ void
michael@0: nsWrapperCache::HoldJSObjects(void* aScriptObjectHolder,
michael@0:                               nsScriptObjectTracer* aTracer)
michael@0: {
michael@0:   cyclecollector::HoldJSObjectsImpl(aScriptObjectHolder, aTracer);
michael@0: }
michael@0: 
michael@0: void
michael@0: nsWrapperCache::ReleaseWrapper(void* aScriptObjectHolder)
michael@0: {
michael@0:   if (PreservingWrapper()) {
michael@0:     // PreserveWrapper puts new DOM bindings in the JS holders hash, but they
michael@0:     // can also be in the DOM expando hash, so we need to try to remove them
michael@0:     // from both here.
michael@0:     JSObject* obj = GetWrapperPreserveColor();
michael@0:     if (IsDOMBinding() && obj && js::IsProxy(obj)) {
michael@0:       DOMProxyHandler::GetAndClearExpandoObject(obj);
michael@0:     }
michael@0:     SetPreservingWrapper(false);
michael@0:     cyclecollector::DropJSObjectsImpl(aScriptObjectHolder);
michael@0:   }
michael@0: }
michael@0: 
michael@0: #ifdef DEBUG
michael@0: 
michael@0: class DebugWrapperTraversalCallback : public nsCycleCollectionTraversalCallback
michael@0: {
michael@0: public:
michael@0:   DebugWrapperTraversalCallback(void* aWrapper)
michael@0:     : mFound(false)
michael@0:     , mWrapper(aWrapper)
michael@0:   {
michael@0:     mFlags = WANT_ALL_TRACES;
michael@0:   }
michael@0: 
michael@0:   NS_IMETHOD_(void) DescribeRefCountedNode(nsrefcnt aRefCount,
michael@0:                                            const char* aObjName)
michael@0:   {
michael@0:   }
michael@0:   NS_IMETHOD_(void) DescribeGCedNode(bool aIsMarked,
michael@0:                                      const char* aObjName,
michael@0:                                      uint64_t aCompartmentAddress)
michael@0:   {
michael@0:   }
michael@0: 
michael@0:   NS_IMETHOD_(void) NoteJSChild(void* aChild)
michael@0:   {
michael@0:     if (aChild == mWrapper) {
michael@0:       mFound = true;
michael@0:     }
michael@0:   }
michael@0:   NS_IMETHOD_(void) NoteXPCOMChild(nsISupports* aChild)
michael@0:   {
michael@0:   }
michael@0:   NS_IMETHOD_(void) NoteNativeChild(void* aChild,
michael@0:                                     nsCycleCollectionParticipant* aHelper)
michael@0:   {
michael@0:   }
michael@0: 
michael@0:   NS_IMETHOD_(void) NoteNextEdgeName(const char* aName)
michael@0:   {
michael@0:   }
michael@0: 
michael@0:   bool mFound;
michael@0: 
michael@0: private:
michael@0:   void* mWrapper;
michael@0: };
michael@0: 
michael@0: static void
michael@0: DebugWrapperTraceCallback(void* aP, const char* aName, void* aClosure)
michael@0: {
michael@0:   DebugWrapperTraversalCallback* callback =
michael@0:     static_cast<DebugWrapperTraversalCallback*>(aClosure);
michael@0:   callback->NoteJSChild(aP);
michael@0: }
michael@0: 
michael@0: void
michael@0: nsWrapperCache::CheckCCWrapperTraversal(void* aScriptObjectHolder,
michael@0:                                         nsScriptObjectTracer* aTracer)
michael@0: {
michael@0:   JSObject* wrapper = GetWrapper();
michael@0:   if (!wrapper) {
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   DebugWrapperTraversalCallback callback(wrapper);
michael@0: 
michael@0:   aTracer->Traverse(aScriptObjectHolder, callback);
michael@0:   MOZ_ASSERT(callback.mFound,
michael@0:              "Cycle collection participant didn't traverse to preserved "
michael@0:              "wrapper! This will probably crash.");
michael@0: 
michael@0:   callback.mFound = false;
michael@0:   aTracer->Trace(aScriptObjectHolder,
michael@0:                  TraceCallbackFunc(DebugWrapperTraceCallback), &callback);
michael@0:   MOZ_ASSERT(callback.mFound,
michael@0:              "Cycle collection participant didn't trace preserved wrapper! "
michael@0:              "This will probably crash.");
michael@0: }
michael@0: 
michael@0: #endif // DEBUG