/* -*- 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 "vm/GlobalObject.h" #include "jsapi.h" #include "jsfriendapi.h" #include "builtin/AtomicsObject.h" #include "builtin/BigInt.h" #include "builtin/DataViewObject.h" #ifdef JS_HAS_INTL_API # include "builtin/intl/Collator.h" # include "builtin/intl/DateTimeFormat.h" # include "builtin/intl/DisplayNames.h" # include "builtin/intl/ListFormat.h" # include "builtin/intl/Locale.h" # include "builtin/intl/NumberFormat.h" # include "builtin/intl/PluralRules.h" # include "builtin/intl/RelativeTimeFormat.h" #endif #include "builtin/FinalizationRegistryObject.h" #include "builtin/MapObject.h" #include "builtin/ShadowRealm.h" #include "builtin/Symbol.h" #include "builtin/WeakMapObject.h" #include "builtin/WeakRefObject.h" #include "builtin/WeakSetObject.h" #include "debugger/DebugAPI.h" #include "frontend/CompilationStencil.h" #include "gc/FinalizationObservers.h" #include "gc/GC.h" #include "gc/GCContext.h" #include "js/friend/ErrorMessages.h" // js::GetErrorMessage, JSMSG_* #include "js/friend/WindowProxy.h" // js::ToWindowProxyIfWindow #include "js/PropertyAndElement.h" // JS_DefineFunctions, JS_DefineProperties #include "js/ProtoKey.h" #include "vm/AsyncFunction.h" #include "vm/AsyncIteration.h" #include "vm/BooleanObject.h" #include "vm/Compartment.h" #include "vm/DateObject.h" #include "vm/EnvironmentObject.h" #include "vm/ErrorObject.h" #include "vm/GeneratorObject.h" #include "vm/JSContext.h" #include "vm/NumberObject.h" #include "vm/PIC.h" #include "vm/PlainObject.h" #include "vm/RegExpObject.h" #include "vm/RegExpStatics.h" #include "vm/SelfHosting.h" #include "vm/StringObject.h" #include "wasm/WasmJS.h" #ifdef ENABLE_RECORD_TUPLE # include "vm/RecordType.h" # include "vm/TupleType.h" #endif #include "gc/GCContext-inl.h" #include "vm/JSObject-inl.h" #include "vm/Realm-inl.h" using namespace js; namespace js { extern const JSClass IntlClass; extern const JSClass JSONClass; extern const JSClass MathClass; extern const JSClass ReflectClass; } // namespace js static const JSClass* const protoTable[JSProto_LIMIT] = { #define INIT_FUNC(name, clasp) clasp, #define INIT_FUNC_DUMMY(name, clasp) nullptr, JS_FOR_PROTOTYPES(INIT_FUNC, INIT_FUNC_DUMMY) #undef INIT_FUNC_DUMMY #undef INIT_FUNC }; JS_PUBLIC_API const JSClass* js::ProtoKeyToClass(JSProtoKey key) { MOZ_ASSERT(key < JSProto_LIMIT); return protoTable[key]; } /* static */ bool GlobalObject::skipDeselectedConstructor(JSContext* cx, JSProtoKey key) { switch (key) { case JSProto_Null: case JSProto_Object: case JSProto_Function: case JSProto_BoundFunction: case JSProto_Array: case JSProto_Boolean: case JSProto_JSON: case JSProto_Date: case JSProto_Math: case JSProto_Number: case JSProto_String: case JSProto_RegExp: case JSProto_Error: case JSProto_InternalError: case JSProto_AggregateError: case JSProto_EvalError: case JSProto_RangeError: case JSProto_ReferenceError: case JSProto_SyntaxError: case JSProto_TypeError: case JSProto_URIError: case JSProto_DebuggeeWouldRun: case JSProto_CompileError: case JSProto_LinkError: case JSProto_RuntimeError: case JSProto_ArrayBuffer: case JSProto_Int8Array: case JSProto_Uint8Array: case JSProto_Int16Array: case JSProto_Uint16Array: case JSProto_Int32Array: case JSProto_Uint32Array: case JSProto_Float32Array: case JSProto_Float64Array: case JSProto_Uint8ClampedArray: case JSProto_BigInt64Array: case JSProto_BigUint64Array: case JSProto_BigInt: case JSProto_Proxy: case JSProto_WeakMap: case JSProto_Map: case JSProto_Set: case JSProto_DataView: case JSProto_Symbol: case JSProto_Reflect: case JSProto_WeakSet: case JSProto_TypedArray: case JSProto_SavedFrame: case JSProto_Promise: case JSProto_AsyncFunction: case JSProto_GeneratorFunction: case JSProto_AsyncGeneratorFunction: #ifdef ENABLE_RECORD_TUPLE case JSProto_Record: case JSProto_Tuple: #endif return false; case JSProto_WebAssembly: return !wasm::HasSupport(cx); case JSProto_WasmModule: case JSProto_WasmInstance: case JSProto_WasmMemory: case JSProto_WasmTable: case JSProto_WasmGlobal: case JSProto_WasmTag: #ifdef ENABLE_WASM_TYPE_REFLECTIONS case JSProto_WasmFunction: #endif case JSProto_WasmException: return false; #ifdef JS_HAS_INTL_API case JSProto_Intl: case JSProto_Collator: case JSProto_DateTimeFormat: case JSProto_DisplayNames: case JSProto_Locale: case JSProto_ListFormat: case JSProto_NumberFormat: case JSProto_PluralRules: case JSProto_RelativeTimeFormat: return false; #endif // Return true if the given constructor has been disabled at run-time. case JSProto_Atomics: case JSProto_SharedArrayBuffer: return !cx->realm()->creationOptions().getSharedMemoryAndAtomicsEnabled(); case JSProto_WeakRef: case JSProto_FinalizationRegistry: return cx->realm()->creationOptions().getWeakRefsEnabled() == JS::WeakRefSpecifier::Disabled; case JSProto_Iterator: case JSProto_AsyncIterator: return !cx->realm()->creationOptions().getIteratorHelpersEnabled(); case JSProto_ShadowRealm: return !cx->realm()->creationOptions().getShadowRealmsEnabled(); default: MOZ_CRASH("unexpected JSProtoKey"); } } static bool ShouldFreezeBuiltin(JSProtoKey key) { switch (key) { case JSProto_Object: case JSProto_Array: case JSProto_Function: return true; default: return false; } } static unsigned GetAttrsForResolvedGlobal(GlobalObject* global, JSProtoKey key) { unsigned attrs = JSPROP_RESOLVING; if (global->realm()->creationOptions().freezeBuiltins() && ShouldFreezeBuiltin(key)) { attrs |= JSPROP_PERMANENT | JSPROP_READONLY; } return attrs; } /* static*/ bool GlobalObject::resolveConstructor(JSContext* cx, Handle global, JSProtoKey key, IfClassIsDisabled mode) { MOZ_ASSERT(key != JSProto_Null); MOZ_ASSERT(key != JSProto_BoundFunction, "bound functions don't have their own proto object"); MOZ_ASSERT(!global->isStandardClassResolved(key)); MOZ_ASSERT(cx->compartment() == global->compartment()); // |global| must be same-compartment but make sure we're in its realm: the // code below relies on this. AutoRealm ar(cx, global); MOZ_ASSERT(!cx->isHelperThreadContext()); // Prohibit collection of allocation metadata. Metadata builders shouldn't // need to observe lazily-constructed prototype objects coming into // existence. And assertions start to fail when the builder itself attempts // an allocation that re-entrantly tries to create the same prototype. AutoSuppressAllocationMetadataBuilder suppressMetadata(cx); // Constructor resolution may execute self-hosted scripts. These // self-hosted scripts do not call out to user code by construction. Allow // all scripts to execute, even in debuggee compartments that are paused. AutoSuppressDebuggeeNoExecuteChecks suppressNX(cx); // Some classes can be disabled at compile time, others at run time; // if a feature is compile-time disabled, clasp is null. const JSClass* clasp = ProtoKeyToClass(key); if (!clasp || skipDeselectedConstructor(cx, key)) { if (mode == IfClassIsDisabled::Throw) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_CONSTRUCTOR_DISABLED, clasp ? clasp->name : "constructor"); return false; } return true; } // Class spec must have a constructor defined. if (!clasp->specDefined()) { return true; } bool isObjectOrFunction = key == JSProto_Function || key == JSProto_Object; // We need to create the prototype first, and immediately stash it in the // slot. This is so the following bootstrap ordering is possible: // * Object.prototype // * Function.prototype // * Function // * Object // // We get the above when Object is resolved before Function. If Function // is resolved before Object, we'll end up re-entering resolveConstructor // for Function, which is a problem. So if Function is being resolved // before Object.prototype exists, we just resolve Object instead, since we // know that Function will also be resolved before we return. if (key == JSProto_Function && !global->hasPrototype(JSProto_Object)) { return resolveConstructor(cx, global, JSProto_Object, IfClassIsDisabled::DoNothing); } // %IteratorPrototype%.map.[[Prototype]] is %Generator% and // %Generator%.prototype.[[Prototype]] is %IteratorPrototype%. // A workaround in initIteratorProto prevents runaway mutual recursion while // setting these up. Ensure the workaround is triggered already: if (key == JSProto_GeneratorFunction && !global->hasBuiltinProto(ProtoKind::IteratorProto)) { if (!getOrCreateIteratorPrototype(cx, global)) { return false; } // If iterator helpers are enabled, populating %IteratorPrototype% will // have recursively gone through here. if (global->isStandardClassResolved(key)) { return true; } } // We don't always have a prototype (i.e. Math and JSON). If we don't, // |createPrototype|, |prototypeFunctions|, and |prototypeProperties| // should all be null. RootedObject proto(cx); if (ClassObjectCreationOp createPrototype = clasp->specCreatePrototypeHook()) { proto = createPrototype(cx, key); if (!proto) { return false; } if (isObjectOrFunction) { // Make sure that creating the prototype didn't recursively resolve // our own constructor. We can't just assert that there's no // prototype; OOMs can result in incomplete resolutions in which // the prototype is saved but not the constructor. So use the same // criteria that protects entry into this function. MOZ_ASSERT(!global->isStandardClassResolved(key)); global->setPrototype(key, proto); } } // Create the constructor. RootedObject ctor(cx, clasp->specCreateConstructorHook()(cx, key)); if (!ctor) { return false; } RootedId id(cx, NameToId(ClassName(key, cx))); if (isObjectOrFunction) { if (clasp->specShouldDefineConstructor()) { RootedValue ctorValue(cx, ObjectValue(*ctor)); unsigned attrs = GetAttrsForResolvedGlobal(global, key); if (!DefineDataProperty(cx, global, id, ctorValue, attrs)) { return false; } } global->setConstructor(key, ctor); } if (const JSFunctionSpec* funs = clasp->specPrototypeFunctions()) { if (!JS_DefineFunctions(cx, proto, funs)) { return false; } } if (const JSPropertySpec* props = clasp->specPrototypeProperties()) { if (!JS_DefineProperties(cx, proto, props)) { return false; } } if (const JSFunctionSpec* funs = clasp->specConstructorFunctions()) { if (!JS_DefineFunctions(cx, ctor, funs)) { return false; } } if (const JSPropertySpec* props = clasp->specConstructorProperties()) { if (!JS_DefineProperties(cx, ctor, props)) { return false; } } // If the prototype exists, link it with the constructor. if (proto && !LinkConstructorAndPrototype(cx, ctor, proto)) { return false; } // Call the post-initialization hook, if provided. if (FinishClassInitOp finishInit = clasp->specFinishInitHook()) { if (!finishInit(cx, ctor, proto)) { return false; } } if (ShouldFreezeBuiltin(key)) { if (!JS::MaybeFreezeCtorAndPrototype(cx, ctor, proto)) { return false; } } if (!isObjectOrFunction) { // Any operations that modifies the global object should be placed // after any other fallible operations. // Fallible operation that modifies the global object. if (clasp->specShouldDefineConstructor()) { bool shouldReallyDefine = true; // On the web, it isn't presently possible to expose the global // "SharedArrayBuffer" property unless the page is cross-site-isolated. // Only define this constructor if an option on the realm indicates that // it should be defined. if (key == JSProto_SharedArrayBuffer) { const JS::RealmCreationOptions& options = global->realm()->creationOptions(); MOZ_ASSERT(options.getSharedMemoryAndAtomicsEnabled(), "shouldn't be defining SharedArrayBuffer if shared memory " "is disabled"); shouldReallyDefine = options.defineSharedArrayBufferConstructor(); } if (shouldReallyDefine) { RootedValue ctorValue(cx, ObjectValue(*ctor)); unsigned attrs = GetAttrsForResolvedGlobal(global, key); if (!DefineDataProperty(cx, global, id, ctorValue, attrs)) { return false; } } } // Infallible operations that modify the global object. global->setConstructor(key, ctor); if (proto) { global->setPrototype(key, proto); } } return true; } // Resolve a "globalThis" self-referential property if necessary, // per a stage-3 proposal. https://github.com/tc39/ecma262/pull/702 // // We could also do this in |FinishObjectClassInit| to trim the global // resolve hook. Unfortunately, |ToWindowProxyIfWindow| doesn't work then: // the browser's |nsGlobalWindow::SetNewDocument| invokes Object init // *before* it sets the global's WindowProxy using |js::SetWindowProxy|. // // Refactoring global object creation code to support this approach is a // challenge for another day. /* static */ bool GlobalObject::maybeResolveGlobalThis(JSContext* cx, Handle global, bool* resolved) { if (!global->data().globalThisResolved) { RootedValue v(cx, ObjectValue(*ToWindowProxyIfWindow(global))); if (!DefineDataProperty(cx, global, cx->names().globalThis, v, JSPROP_RESOLVING)) { return false; } *resolved = true; global->data().globalThisResolved = true; } return true; } /* static */ JSObject* GlobalObject::createBuiltinProto(JSContext* cx, Handle global, ProtoKind kind, ObjectInitOp init) { MOZ_ASSERT(!cx->isHelperThreadContext()); if (!init(cx, global)) { return nullptr; } return &global->getBuiltinProto(kind); } JSObject* GlobalObject::createBuiltinProto(JSContext* cx, Handle global, ProtoKind kind, Handle tag, ObjectInitWithTagOp init) { MOZ_ASSERT(!cx->isHelperThreadContext()); if (!init(cx, global, tag)) { return nullptr; } return &global->getBuiltinProto(kind); } static bool ThrowTypeError(JSContext* cx, unsigned argc, Value* vp) { ThrowTypeErrorBehavior(cx); return false; } /* static */ JSObject* GlobalObject::getOrCreateThrowTypeError( JSContext* cx, Handle global) { if (JSFunction* fun = global->data().throwTypeError) { return fun; } // Construct the unique [[%ThrowTypeError%]] function object, used only for // "callee" and "caller" accessors on strict mode arguments objects. (The // spec also uses this for "arguments" and "caller" on various functions, // but we're experimenting with implementing them using accessors on // |Function.prototype| right now.) RootedFunction throwTypeError( cx, NewNativeFunction(cx, ThrowTypeError, 0, nullptr)); if (!throwTypeError || !PreventExtensions(cx, throwTypeError)) { return nullptr; } // The "length" property of %ThrowTypeError% is non-configurable. Rooted nonConfigurableDesc(cx, PropertyDescriptor::Empty()); nonConfigurableDesc.setConfigurable(false); RootedId lengthId(cx, NameToId(cx->names().length)); ObjectOpResult lengthResult; if (!NativeDefineProperty(cx, throwTypeError, lengthId, nonConfigurableDesc, lengthResult)) { return nullptr; } MOZ_ASSERT(lengthResult); // The "name" property of %ThrowTypeError% is non-configurable, adjust // the default property attributes accordingly. RootedId nameId(cx, NameToId(cx->names().name)); ObjectOpResult nameResult; if (!NativeDefineProperty(cx, throwTypeError, nameId, nonConfigurableDesc, nameResult)) { return nullptr; } MOZ_ASSERT(nameResult); global->data().throwTypeError.init(throwTypeError); return throwTypeError; } GlobalObject* GlobalObject::createInternal(JSContext* cx, const JSClass* clasp) { MOZ_ASSERT(clasp->flags & JSCLASS_IS_GLOBAL); MOZ_ASSERT(clasp->isTrace(JS_GlobalObjectTraceHook)); JSObject* obj = NewTenuredObjectWithGivenProto(cx, clasp, nullptr); if (!obj) { return nullptr; } Rooted global(cx, &obj->as()); MOZ_ASSERT(global->isUnqualifiedVarObj()); { auto data = cx->make_unique(cx->zone()); if (!data) { return nullptr; } // Note: it's important for the realm's global to be initialized at the // same time as the global's GlobalObjectData, because we free the global's // data when Realm::global_ is cleared. cx->realm()->initGlobal(*global); InitReservedSlot(global, GLOBAL_DATA_SLOT, data.release(), MemoryUse::GlobalObjectData); } Rooted lexical( cx, GlobalLexicalEnvironmentObject::create(cx, global)); if (!lexical) { return nullptr; } global->data().lexicalEnvironment.init(lexical); Rooted emptyGlobalScope( cx, GlobalScope::createEmpty(cx, ScopeKind::Global)); if (!emptyGlobalScope) { return nullptr; } global->data().emptyGlobalScope.init(emptyGlobalScope); if (!GlobalObject::createIntrinsicsHolder(cx, global)) { return nullptr; } if (!JSObject::setQualifiedVarObj(cx, global)) { return nullptr; } if (!JSObject::setGenerationCountedGlobal(cx, global)) { return nullptr; } return global; } /* static */ GlobalObject* GlobalObject::new_(JSContext* cx, const JSClass* clasp, JSPrincipals* principals, JS::OnNewGlobalHookOption hookOption, const JS::RealmOptions& options) { MOZ_ASSERT(!cx->isExceptionPending()); MOZ_ASSERT_IF(cx->zone(), !cx->zone()->isAtomsZone()); // If we are creating a new global in an existing compartment, make sure the // compartment has a live global at all times (by rooting it here). // See bug 1530364. Rooted existingGlobal(cx); const JS::RealmCreationOptions& creationOptions = options.creationOptions(); if (creationOptions.compartmentSpecifier() == JS::CompartmentSpecifier::ExistingCompartment) { Compartment* comp = creationOptions.compartment(); existingGlobal = &comp->firstGlobal(); } Realm* realm = NewRealm(cx, principals, options); if (!realm) { return nullptr; } Rooted global(cx); { AutoRealmUnchecked ar(cx, realm); global = GlobalObject::createInternal(cx, clasp); if (!global) { return nullptr; } // Make transactional initialization of these constructors by discarding the // incompletely initialized global if an error occur. This also ensures the // global's prototype chain is initialized (in FinishObjectClassInit). if (!ensureConstructor(cx, global, JSProto_Object) || !ensureConstructor(cx, global, JSProto_Function)) { return nullptr; } realm->clearInitializingGlobal(); if (hookOption == JS::FireOnNewGlobalHook) { JS_FireOnNewGlobalObject(cx, global); } } return global; } GlobalScope& GlobalObject::emptyGlobalScope() const { return *data().emptyGlobalScope; } bool GlobalObject::valueIsEval(const Value& val) { return val.isObject() && data().eval == &val.toObject(); } /* static */ bool GlobalObject::initStandardClasses(JSContext* cx, Handle global) { /* Define a top-level property 'undefined' with the undefined value. */ if (!DefineDataProperty( cx, global, cx->names().undefined, UndefinedHandleValue, JSPROP_PERMANENT | JSPROP_READONLY | JSPROP_RESOLVING)) { return false; } // Resolve a "globalThis" self-referential property if necessary. bool resolved; if (!GlobalObject::maybeResolveGlobalThis(cx, global, &resolved)) { return false; } for (size_t k = 0; k < JSProto_LIMIT; ++k) { JSProtoKey key = static_cast(k); if (key != JSProto_Null && key != JSProto_BoundFunction && !global->isStandardClassResolved(key)) { if (!resolveConstructor(cx, global, static_cast(k), IfClassIsDisabled::DoNothing)) { return false; } } } return true; } /* static */ JSFunction* GlobalObject::createConstructor(JSContext* cx, Native ctor, JSAtom* nameArg, unsigned length, gc::AllocKind kind, const JSJitInfo* jitInfo) { Rooted name(cx, nameArg); JSFunction* fun = NewNativeConstructor(cx, ctor, length, name, kind); if (!fun) { return nullptr; } if (jitInfo) { fun->setJitInfo(jitInfo); } return fun; } static NativeObject* CreateBlankProto(JSContext* cx, const JSClass* clasp, HandleObject proto) { MOZ_ASSERT(!clasp->isJSFunction()); if (clasp == &PlainObject::class_) { return NewPlainObjectWithProto(cx, proto, TenuredObject); } return NewTenuredObjectWithGivenProto(cx, clasp, proto); } /* static */ NativeObject* GlobalObject::createBlankPrototype(JSContext* cx, Handle global, const JSClass* clasp) { RootedObject objectProto(cx, &global->getObjectPrototype()); return CreateBlankProto(cx, clasp, objectProto); } /* static */ NativeObject* GlobalObject::createBlankPrototypeInheriting(JSContext* cx, const JSClass* clasp, HandleObject proto) { return CreateBlankProto(cx, clasp, proto); } bool js::LinkConstructorAndPrototype(JSContext* cx, JSObject* ctor_, JSObject* proto_, unsigned prototypeAttrs, unsigned constructorAttrs) { RootedObject ctor(cx, ctor_), proto(cx, proto_); RootedValue protoVal(cx, ObjectValue(*proto)); RootedValue ctorVal(cx, ObjectValue(*ctor)); return DefineDataProperty(cx, ctor, cx->names().prototype, protoVal, prototypeAttrs) && DefineDataProperty(cx, proto, cx->names().constructor, ctorVal, constructorAttrs); } bool js::DefinePropertiesAndFunctions(JSContext* cx, HandleObject obj, const JSPropertySpec* ps, const JSFunctionSpec* fs) { if (ps && !JS_DefineProperties(cx, obj, ps)) { return false; } if (fs && !JS_DefineFunctions(cx, obj, fs)) { return false; } return true; } bool js::DefineToStringTag(JSContext* cx, HandleObject obj, JSAtom* tag) { RootedId toStringTagId( cx, PropertyKey::Symbol(cx->wellKnownSymbols().toStringTag)); RootedValue tagString(cx, StringValue(tag)); return DefineDataProperty(cx, obj, toStringTagId, tagString, JSPROP_READONLY); } /* static */ NativeObject* GlobalObject::getOrCreateForOfPICObject( JSContext* cx, Handle global) { cx->check(global); NativeObject* forOfPIC = global->getForOfPICObject(); if (forOfPIC) { return forOfPIC; } forOfPIC = ForOfPIC::createForOfPICObject(cx, global); if (!forOfPIC) { return nullptr; } global->data().forOfPICChain.init(forOfPIC); return forOfPIC; } /* static */ JSObject* GlobalObject::getOrCreateRealmKeyObject( JSContext* cx, Handle global) { cx->check(global); if (PlainObject* key = global->data().realmKeyObject) { return key; } PlainObject* key = NewPlainObject(cx); if (!key) { return nullptr; } global->data().realmKeyObject.init(key); return key; } /* static */ RegExpStatics* GlobalObject::getRegExpStatics(JSContext* cx, Handle global) { MOZ_ASSERT(cx); if (!global->data().regExpStatics) { auto statics = RegExpStatics::create(cx); if (!statics) { return nullptr; } global->data().regExpStatics = std::move(statics); } return global->data().regExpStatics.get(); } gc::FinalizationRegistryGlobalData* GlobalObject::getOrCreateFinalizationRegistryData() { if (!data().finalizationRegistryData) { data().finalizationRegistryData = MakeUnique(zone()); } return maybeFinalizationRegistryData(); } bool GlobalObject::addToVarNames(JSContext* cx, JS::Handle name) { MOZ_ASSERT(name); if (!data().varNames.put(name)) { ReportOutOfMemory(cx); return false; } return true; } /* static */ bool GlobalObject::createIntrinsicsHolder(JSContext* cx, Handle global) { Rooted intrinsicsHolder( cx, NewPlainObjectWithProto(cx, nullptr, TenuredObject)); if (!intrinsicsHolder) { return false; } // Install the intrinsics holder on the global. global->data().intrinsicsHolder.init(intrinsicsHolder); return true; } /* static */ bool GlobalObject::getSelfHostedFunction(JSContext* cx, Handle global, Handle selfHostedName, Handle name, unsigned nargs, MutableHandleValue funVal) { if (global->maybeGetIntrinsicValue(selfHostedName, funVal.address(), cx)) { RootedFunction fun(cx, &funVal.toObject().as()); if (fun->explicitName() == name) { return true; } if (fun->explicitName() == selfHostedName) { // This function was initially cloned because it was called by // other self-hosted code, so the clone kept its self-hosted name, // instead of getting the name it's intended to have in content // compartments. This can happen when a lazy builtin is initialized // after self-hosted code for another builtin used the same // function. In that case, we need to change the function's name, // which is ok because it can't have been exposed to content // before. fun->setAtom(name); return true; } // The function might be installed multiple times on the same or // different builtins, under different property names, so its name // might be neither "selfHostedName" nor "name". In that case, its // canonical name must've been set using the `_SetCanonicalName` // intrinsic. cx->runtime()->assertSelfHostedFunctionHasCanonicalName(selfHostedName); return true; } JSRuntime* runtime = cx->runtime(); frontend::ScriptIndex index = runtime->getSelfHostedScriptIndexRange(selfHostedName)->start; JSFunction* fun = runtime->selfHostStencil().instantiateSelfHostedLazyFunction( cx, runtime->selfHostStencilInput().atomCache, index, name); if (!fun) { return false; } MOZ_ASSERT(fun->nargs() == nargs); funVal.setObject(*fun); return GlobalObject::addIntrinsicValue(cx, global, selfHostedName, funVal); } /* static */ bool GlobalObject::getIntrinsicValueSlow(JSContext* cx, Handle global, Handle name, MutableHandleValue value) { // If this is a C++ intrinsic, simply define the function on the intrinsics // holder. if (const JSFunctionSpec* spec = js::FindIntrinsicSpec(name)) { RootedId id(cx, NameToId(name)); RootedFunction fun(cx, JS::NewFunctionFromSpec(cx, spec, id)); if (!fun) { return false; } fun->setIsIntrinsic(); value.setObject(*fun); return GlobalObject::addIntrinsicValue(cx, global, name, value); } if (!cx->runtime()->getSelfHostedValue(cx, name, value)) { return false; } // It's possible in certain edge cases that cloning the value ended up // defining the intrinsic. For instance, cloning can call NewArray, which // resolves Array.prototype, which defines some self-hosted functions. If this // happens we use the value already defined on the intrinsics holder. if (global->maybeGetIntrinsicValue(name, value.address(), cx)) { return true; } return GlobalObject::addIntrinsicValue(cx, global, name, value); } /* static */ bool GlobalObject::addIntrinsicValue(JSContext* cx, Handle global, Handle name, HandleValue value) { Rooted holder(cx, &global->getIntrinsicsHolder()); RootedId id(cx, NameToId(name)); MOZ_ASSERT(!holder->containsPure(id)); constexpr PropertyFlags propFlags = {PropertyFlag::Configurable, PropertyFlag::Writable}; uint32_t slot; if (!NativeObject::addProperty(cx, holder, id, propFlags, &slot)) { return false; } holder->initSlot(slot, value); return true; } /* static */ JSObject* GlobalObject::createIteratorPrototype(JSContext* cx, Handle global) { if (!cx->realm()->creationOptions().getIteratorHelpersEnabled()) { return getOrCreateBuiltinProto(cx, global, ProtoKind::IteratorProto, initIteratorProto); } if (!ensureConstructor(cx, global, JSProto_Iterator)) { return nullptr; } JSObject* proto = &global->getPrototype(JSProto_Iterator); global->initBuiltinProto(ProtoKind::IteratorProto, proto); return proto; } /* static */ JSObject* GlobalObject::createAsyncIteratorPrototype( JSContext* cx, Handle global) { if (!cx->realm()->creationOptions().getIteratorHelpersEnabled()) { return getOrCreateBuiltinProto(cx, global, ProtoKind::AsyncIteratorProto, initAsyncIteratorProto); } if (!ensureConstructor(cx, global, JSProto_AsyncIterator)) { return nullptr; } JSObject* proto = &global->getPrototype(JSProto_AsyncIterator); global->initBuiltinProto(ProtoKind::AsyncIteratorProto, proto); return proto; } void GlobalObject::releaseData(JS::GCContext* gcx) { GlobalObjectData* data = maybeData(); setReservedSlot(GLOBAL_DATA_SLOT, PrivateValue(nullptr)); gcx->delete_(this, data, MemoryUse::GlobalObjectData); } GlobalObjectData::GlobalObjectData(Zone* zone) : varNames(zone) {} GlobalObjectData::~GlobalObjectData() = default; void GlobalObjectData::trace(JSTracer* trc, GlobalObject* global) { // Atoms are always tenured so don't need to be traced during minor GC. if (trc->runtime()->heapState() != JS::HeapState::MinorCollecting) { varNames.trace(trc); } for (auto& ctorWithProto : builtinConstructors) { TraceNullableEdge(trc, &ctorWithProto.constructor, "global-builtin-ctor"); TraceNullableEdge(trc, &ctorWithProto.prototype, "global-builtin-ctor-proto"); } for (auto& proto : builtinProtos) { TraceNullableEdge(trc, &proto, "global-builtin-proto"); } TraceNullableEdge(trc, &emptyGlobalScope, "global-empty-scope"); TraceNullableEdge(trc, &lexicalEnvironment, "global-lexical-env"); TraceNullableEdge(trc, &windowProxy, "global-window-proxy"); TraceNullableEdge(trc, &intrinsicsHolder, "global-intrinsics-holder"); TraceNullableEdge(trc, &computedIntrinsicsHolder, "global-computed-intrinsics-holder"); TraceNullableEdge(trc, &forOfPICChain, "global-for-of-pic"); TraceNullableEdge(trc, &sourceURLsHolder, "global-source-urls"); TraceNullableEdge(trc, &realmKeyObject, "global-realm-key"); TraceNullableEdge(trc, &throwTypeError, "global-throw-type-error"); TraceNullableEdge(trc, &eval, "global-eval"); TraceNullableEdge(trc, &emptyIterator, "global-empty-iterator"); TraceNullableEdge(trc, &arrayShapeWithDefaultProto, "global-array-shape"); for (auto& shape : plainObjectShapesWithDefaultProto) { TraceNullableEdge(trc, &shape, "global-plain-shape"); } TraceNullableEdge(trc, &functionShapeWithDefaultProto, "global-function-shape"); TraceNullableEdge(trc, &extendedFunctionShapeWithDefaultProto, "global-ext-function-shape"); TraceNullableEdge(trc, &boundFunctionShapeWithDefaultProto, "global-bound-function-shape"); if (regExpStatics) { regExpStatics->trace(trc); } TraceNullableEdge(trc, &mappedArgumentsTemplate, "mapped-arguments-template"); TraceNullableEdge(trc, &unmappedArgumentsTemplate, "unmapped-arguments-template"); TraceNullableEdge(trc, &iterResultTemplate, "iter-result-template_"); TraceNullableEdge(trc, &iterResultWithoutPrototypeTemplate, "iter-result-without-prototype-template"); TraceNullableEdge(trc, &selfHostingScriptSource, "self-hosting-script-source"); if (finalizationRegistryData) { finalizationRegistryData->trace(trc); } } void GlobalObjectData::addSizeOfIncludingThis( mozilla::MallocSizeOf mallocSizeOf, JS::ClassInfo* info) const { info->objectsMallocHeapGlobalData += mallocSizeOf(this); if (regExpStatics) { info->objectsMallocHeapGlobalData += regExpStatics->sizeOfIncludingThis(mallocSizeOf); } info->objectsMallocHeapGlobalVarNamesSet += varNames.shallowSizeOfExcludingThis(mallocSizeOf); }