/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* vim: set ts=8 sts=2 et sw=2 tw=80: */ /* This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this file, * You can obtain one at http://mozilla.org/MPL/2.0/. */ /** * A simplere nsIGlobalObject implementation that can be used to set up a new * global without anything interesting in it other than the JS builtins. This * is safe to use on both mainthread and worker threads. */ #ifndef mozilla_dom_SimpleGlobalObject_h__ #define mozilla_dom_SimpleGlobalObject_h__ #include "nsContentUtils.h" #include "nsIGlobalObject.h" #include "nsWrapperCache.h" #include "js/TypeDecls.h" #include "js/Value.h" #include "nsISupportsImpl.h" #include "nsCycleCollectionParticipant.h" namespace mozilla::dom { class SimpleGlobalObject : public nsIGlobalObject, public nsWrapperCache { public: enum class GlobalType { BindingDetail, // Should only be used by DOM bindings code. WorkerDebuggerSandbox, NotSimpleGlobal // Sentinel to be used by BasicGlobalType. }; // Create a new JS global object that can be used to do some work. This // global will NOT have any DOM APIs exposed in it, will not be visible to the // debugger, and will not have a useful concept of principals, so don't try to // use it with any DOM objects. Apart from that, running code with // side-effects is safe in this global. Importantly, when you are first // handed this global it's guaranteed to have pristine built-ins. The // corresponding nsIGlobalObject* for this global object will be a // SimpleGlobalObject of the type provided; JS::GetPrivate on the returned // JSObject* will return the SimpleGlobalObject*. // // If the provided prototype value is undefined, it is ignored. If it's an // object or null, it's set as the prototype of the created global. If it's // anything else, this function returns null. // // Note that creating new globals is not cheap and should not be done // gratuitously. Please think carefully before you use this function. static JSObject* Create(GlobalType globalType, JS::Handle proto = JS::UndefinedHandleValue); NS_DECL_CYCLE_COLLECTING_ISUPPORTS NS_DECL_CYCLE_COLLECTION_WRAPPERCACHE_CLASS(SimpleGlobalObject) // Gets the GlobalType of this SimpleGlobalObject. GlobalType Type() const { return mType; } // Gets the GlobalType of the SimpleGlobalObject for the given JSObject*, if // the given JSObject* is the global corresponding to a SimpleGlobalObject. // Oherwise, returns GlobalType::NotSimpleGlobal. static GlobalType SimpleGlobalType(JSObject* obj); JSObject* GetGlobalJSObject() override { return GetWrapper(); } JSObject* GetGlobalJSObjectPreserveColor() const override { return GetWrapperPreserveColor(); } OriginTrials Trials() const override { return {}; } JSObject* WrapObject(JSContext* cx, JS::Handle aGivenProto) override { MOZ_CRASH("SimpleGlobalObject doesn't use DOM bindings!"); } bool ShouldResistFingerprinting() const override { return nsContentUtils::ShouldResistFingerprinting( "Presently we don't have enough context to make an informed decision" "on JS Sandboxes. See 1782853"); } private: SimpleGlobalObject(JSObject* global, GlobalType type) : mType(type) { SetWrapper(global); } virtual ~SimpleGlobalObject() { MOZ_ASSERT(!GetWrapperMaybeDead()); } const GlobalType mType; }; } // namespace mozilla::dom #endif /* mozilla_dom_SimpleGlobalObject_h__ */