diff options
Diffstat (limited to '')
-rw-r--r-- | dom/bindings/SimpleGlobalObject.h | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/dom/bindings/SimpleGlobalObject.h b/dom/bindings/SimpleGlobalObject.h new file mode 100644 index 0000000000..9358c498ef --- /dev/null +++ b/dom/bindings/SimpleGlobalObject.h @@ -0,0 +1,103 @@ +/* -*- 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 "nsThreadUtils.h" +#include "nsContentUtils.h" +#include "nsCycleCollectionParticipant.h" +#include "nsIGlobalObject.h" +#include "nsISupportsImpl.h" +#include "nsWrapperCache.h" +#include "js/TypeDecls.h" +#include "js/Value.h" + +namespace mozilla::dom { + +class SimpleGlobalObject final : 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<JS::Value> 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 {}; } + + nsISerialEventTarget* SerialEventTarget() const final { + return NS_GetCurrentThread(); + } + nsresult Dispatch(already_AddRefed<nsIRunnable>&& aRunnable) const final { + return NS_DispatchToCurrentThread(std::move(aRunnable)); + } + + JSObject* WrapObject(JSContext* cx, + JS::Handle<JSObject*> aGivenProto) override { + MOZ_CRASH("SimpleGlobalObject doesn't use DOM bindings!"); + } + + bool ShouldResistFingerprinting(RFPTarget aTarget) const override { + return nsContentUtils::ShouldResistFingerprinting( + "Presently we don't have enough context to make an informed decision" + "on JS Sandboxes. See 1782853", + aTarget); + } + + 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__ */ |