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Diffstat (limited to '')
| -rw-r--r-- | dom/bindings/SimpleGlobalObject.cpp | 177 |
1 files changed, 177 insertions, 0 deletions
diff --git a/dom/bindings/SimpleGlobalObject.cpp b/dom/bindings/SimpleGlobalObject.cpp new file mode 100644 index 0000000000..798efc94c1 --- /dev/null +++ b/dom/bindings/SimpleGlobalObject.cpp @@ -0,0 +1,177 @@ +/* -*- 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/. */ + +#include "mozilla/dom/SimpleGlobalObject.h" + +#include "jsapi.h" +#include "js/Class.h" +#include "js/Object.h" // JS::GetClass, JS::GetObjectISupports, JS::SetObjectISupports + +#include "nsJSPrincipals.h" +#include "nsThreadUtils.h" +#include "nsContentUtils.h" + +#include "xpcprivate.h" + +#include "mozilla/dom/ScriptSettings.h" +#include "mozilla/NullPrincipal.h" + +namespace mozilla::dom { + +NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE_CLASS(SimpleGlobalObject) + +NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(SimpleGlobalObject) + NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER + tmp->UnlinkObjectsInGlobal(); +NS_IMPL_CYCLE_COLLECTION_UNLINK_END + +NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(SimpleGlobalObject) + tmp->TraverseObjectsInGlobal(cb); +NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END + +NS_IMPL_CYCLE_COLLECTING_ADDREF(SimpleGlobalObject) +NS_IMPL_CYCLE_COLLECTING_RELEASE(SimpleGlobalObject) +NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(SimpleGlobalObject) + NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY + NS_INTERFACE_MAP_ENTRY(nsIGlobalObject) +NS_INTERFACE_MAP_END + +static SimpleGlobalObject* GetSimpleGlobal(JSObject* global); + +static void SimpleGlobal_finalize(JS::GCContext* gcx, JSObject* obj) { + SimpleGlobalObject* globalObject = GetSimpleGlobal(obj); + if (globalObject) { + globalObject->ClearWrapper(obj); + NS_RELEASE(globalObject); + } +} + +static size_t SimpleGlobal_moved(JSObject* obj, JSObject* old) { + SimpleGlobalObject* globalObject = GetSimpleGlobal(obj); + if (globalObject) { + globalObject->UpdateWrapper(obj, old); + } + return 0; +} + +static const JSClassOps SimpleGlobalClassOps = { + nullptr, + nullptr, + nullptr, + JS_NewEnumerateStandardClasses, + JS_ResolveStandardClass, + JS_MayResolveStandardClass, + SimpleGlobal_finalize, + nullptr, + nullptr, + JS_GlobalObjectTraceHook, +}; + +static const js::ClassExtension SimpleGlobalClassExtension = { + SimpleGlobal_moved}; + +static_assert(JSCLASS_GLOBAL_APPLICATION_SLOTS > 0, + "Need at least one slot for JSCLASS_SLOT0_IS_NSISUPPORTS"); + +const JSClass SimpleGlobalClass = {"", + JSCLASS_GLOBAL_FLAGS | + JSCLASS_SLOT0_IS_NSISUPPORTS | + JSCLASS_FOREGROUND_FINALIZE, + &SimpleGlobalClassOps, + JS_NULL_CLASS_SPEC, + &SimpleGlobalClassExtension, + JS_NULL_OBJECT_OPS}; + +static SimpleGlobalObject* GetSimpleGlobal(JSObject* global) { + MOZ_ASSERT(JS::GetClass(global) == &SimpleGlobalClass); + + return JS::GetObjectISupports<SimpleGlobalObject>(global); +} + +// static +JSObject* SimpleGlobalObject::Create(GlobalType globalType, + JS::Handle<JS::Value> proto) { + // We can't root our return value with our AutoJSAPI because the rooting + // analysis thinks ~AutoJSAPI can GC. So we need to root in a scope outside + // the lifetime of the AutoJSAPI. + JS::Rooted<JSObject*> global(RootingCx()); + + { // Scope to ensure the AutoJSAPI destructor runs before we end up returning + AutoJSAPI jsapi; + jsapi.Init(); + JSContext* cx = jsapi.cx(); + + JS::RealmOptions options; + options.creationOptions() + .setInvisibleToDebugger(true) + // Put our SimpleGlobalObjects in the system zone, so we won't create + // lots of zones for what are probably very short-lived + // compartments. This should help them be GCed quicker and take up + // less memory before they're GCed. + .setNewCompartmentInSystemZone(); + + if (NS_IsMainThread()) { + nsCOMPtr<nsIPrincipal> principal = + NullPrincipal::CreateWithoutOriginAttributes(); + options.creationOptions().setTrace(xpc::TraceXPCGlobal); + global = xpc::CreateGlobalObject(cx, &SimpleGlobalClass, + nsJSPrincipals::get(principal), options); + } else { + global = JS_NewGlobalObject(cx, &SimpleGlobalClass, nullptr, + JS::DontFireOnNewGlobalHook, options); + } + + if (!global) { + jsapi.ClearException(); + return nullptr; + } + + JSAutoRealm ar(cx, global); + + // It's important to create the nsIGlobalObject for our new global before we + // start trying to wrap things like the prototype into its compartment, + // because the wrap operation relies on the global having its + // nsIGlobalObject already. + RefPtr<SimpleGlobalObject> globalObject = + new SimpleGlobalObject(global, globalType); + + // Pass on ownership of globalObject to |global|. + JS::SetObjectISupports(global, globalObject.forget().take()); + + if (proto.isObjectOrNull()) { + JS::Rooted<JSObject*> protoObj(cx, proto.toObjectOrNull()); + if (!JS_WrapObject(cx, &protoObj)) { + jsapi.ClearException(); + return nullptr; + } + + if (!JS_SetPrototype(cx, global, protoObj)) { + jsapi.ClearException(); + return nullptr; + } + } else if (!proto.isUndefined()) { + // Bogus proto. + return nullptr; + } + + JS_FireOnNewGlobalObject(cx, global); + } + + return global; +} + +// static +SimpleGlobalObject::GlobalType SimpleGlobalObject::SimpleGlobalType( + JSObject* obj) { + if (JS::GetClass(obj) != &SimpleGlobalClass) { + return SimpleGlobalObject::GlobalType::NotSimpleGlobal; + } + + SimpleGlobalObject* globalObject = GetSimpleGlobal(obj); + return globalObject->Type(); +} + +} // namespace mozilla::dom |