/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- * vim: set ts=8 sts=4 et sw=4 tw=99: * 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 "builtin/WeakMapObject.h" #include "jsapi.h" #include "jscntxt.h" #include "vm/SelfHosting.h" #include "vm/Interpreter-inl.h" using namespace js; using namespace js::gc; MOZ_ALWAYS_INLINE bool IsWeakMap(HandleValue v) { return v.isObject() && v.toObject().is<WeakMapObject>(); } MOZ_ALWAYS_INLINE bool WeakMap_has_impl(JSContext* cx, const CallArgs& args) { MOZ_ASSERT(IsWeakMap(args.thisv())); if (!args.get(0).isObject()) { args.rval().setBoolean(false); return true; } if (ObjectValueMap* map = args.thisv().toObject().as<WeakMapObject>().getMap()) { JSObject* key = &args[0].toObject(); if (map->has(key)) { args.rval().setBoolean(true); return true; } } args.rval().setBoolean(false); return true; } bool js::WeakMap_has(JSContext* cx, unsigned argc, Value* vp) { CallArgs args = CallArgsFromVp(argc, vp); return CallNonGenericMethod<IsWeakMap, WeakMap_has_impl>(cx, args); } MOZ_ALWAYS_INLINE bool WeakMap_get_impl(JSContext* cx, const CallArgs& args) { MOZ_ASSERT(IsWeakMap(args.thisv())); if (!args.get(0).isObject()) { args.rval().setUndefined(); return true; } if (ObjectValueMap* map = args.thisv().toObject().as<WeakMapObject>().getMap()) { JSObject* key = &args[0].toObject(); if (ObjectValueMap::Ptr ptr = map->lookup(key)) { args.rval().set(ptr->value()); return true; } } args.rval().setUndefined(); return true; } bool js::WeakMap_get(JSContext* cx, unsigned argc, Value* vp) { CallArgs args = CallArgsFromVp(argc, vp); return CallNonGenericMethod<IsWeakMap, WeakMap_get_impl>(cx, args); } MOZ_ALWAYS_INLINE bool WeakMap_delete_impl(JSContext* cx, const CallArgs& args) { MOZ_ASSERT(IsWeakMap(args.thisv())); if (!args.get(0).isObject()) { args.rval().setBoolean(false); return true; } if (ObjectValueMap* map = args.thisv().toObject().as<WeakMapObject>().getMap()) { JSObject* key = &args[0].toObject(); if (ObjectValueMap::Ptr ptr = map->lookup(key)) { map->remove(ptr); args.rval().setBoolean(true); return true; } } args.rval().setBoolean(false); return true; } bool js::WeakMap_delete(JSContext* cx, unsigned argc, Value* vp) { CallArgs args = CallArgsFromVp(argc, vp); return CallNonGenericMethod<IsWeakMap, WeakMap_delete_impl>(cx, args); } static bool TryPreserveReflector(JSContext* cx, HandleObject obj) { if (obj->getClass()->isWrappedNative() || obj->getClass()->isDOMClass() || (obj->is<ProxyObject>() && obj->as<ProxyObject>().handler()->family() == GetDOMProxyHandlerFamily())) { MOZ_ASSERT(cx->runtime()->preserveWrapperCallback); if (!cx->runtime()->preserveWrapperCallback(cx, obj)) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_BAD_WEAKMAP_KEY); return false; } } return true; } static MOZ_ALWAYS_INLINE bool SetWeakMapEntryInternal(JSContext* cx, Handle<WeakMapObject*> mapObj, HandleObject key, HandleValue value) { ObjectValueMap* map = mapObj->getMap(); if (!map) { auto newMap = cx->make_unique<ObjectValueMap>(cx, mapObj.get()); if (!newMap) return false; if (!newMap->init()) { JS_ReportOutOfMemory(cx); return false; } map = newMap.release(); mapObj->setPrivate(map); } // Preserve wrapped native keys to prevent wrapper optimization. if (!TryPreserveReflector(cx, key)) return false; if (JSWeakmapKeyDelegateOp op = key->getClass()->extWeakmapKeyDelegateOp()) { RootedObject delegate(cx, op(key)); if (delegate && !TryPreserveReflector(cx, delegate)) return false; } MOZ_ASSERT(key->compartment() == mapObj->compartment()); MOZ_ASSERT_IF(value.isObject(), value.toObject().compartment() == mapObj->compartment()); if (!map->put(key, value)) { JS_ReportOutOfMemory(cx); return false; } return true; } MOZ_ALWAYS_INLINE bool WeakMap_set_impl(JSContext* cx, const CallArgs& args) { MOZ_ASSERT(IsWeakMap(args.thisv())); if (!args.get(0).isObject()) { UniqueChars bytes = DecompileValueGenerator(cx, JSDVG_SEARCH_STACK, args.get(0), nullptr); if (!bytes) return false; JS_ReportErrorNumberLatin1(cx, GetErrorMessage, nullptr, JSMSG_NOT_NONNULL_OBJECT, bytes.get()); return false; } RootedObject key(cx, &args[0].toObject()); Rooted<JSObject*> thisObj(cx, &args.thisv().toObject()); Rooted<WeakMapObject*> map(cx, &thisObj->as<WeakMapObject>()); if (!SetWeakMapEntryInternal(cx, map, key, args.get(1))) return false; args.rval().set(args.thisv()); return true; } bool js::WeakMap_set(JSContext* cx, unsigned argc, Value* vp) { CallArgs args = CallArgsFromVp(argc, vp); return CallNonGenericMethod<IsWeakMap, WeakMap_set_impl>(cx, args); } JS_FRIEND_API(bool) JS_NondeterministicGetWeakMapKeys(JSContext* cx, HandleObject objArg, MutableHandleObject ret) { RootedObject obj(cx, objArg); obj = UncheckedUnwrap(obj); if (!obj || !obj->is<WeakMapObject>()) { ret.set(nullptr); return true; } RootedObject arr(cx, NewDenseEmptyArray(cx)); if (!arr) return false; ObjectValueMap* map = obj->as<WeakMapObject>().getMap(); if (map) { // Prevent GC from mutating the weakmap while iterating. AutoSuppressGC suppress(cx); for (ObjectValueMap::Base::Range r = map->all(); !r.empty(); r.popFront()) { JS::ExposeObjectToActiveJS(r.front().key()); RootedObject key(cx, r.front().key()); if (!cx->compartment()->wrap(cx, &key)) return false; if (!NewbornArrayPush(cx, arr, ObjectValue(*key))) return false; } } ret.set(arr); return true; } static void WeakMap_mark(JSTracer* trc, JSObject* obj) { if (ObjectValueMap* map = obj->as<WeakMapObject>().getMap()) map->trace(trc); } static void WeakMap_finalize(FreeOp* fop, JSObject* obj) { MOZ_ASSERT(fop->maybeOffMainThread()); if (ObjectValueMap* map = obj->as<WeakMapObject>().getMap()) { #ifdef DEBUG map->~ObjectValueMap(); memset(static_cast<void*>(map), 0xdc, sizeof(*map)); fop->free_(map); #else fop->delete_(map); #endif } } JS_PUBLIC_API(JSObject*) JS::NewWeakMapObject(JSContext* cx) { return NewBuiltinClassInstance(cx, &WeakMapObject::class_); } JS_PUBLIC_API(bool) JS::IsWeakMapObject(JSObject* obj) { return obj->is<WeakMapObject>(); } JS_PUBLIC_API(bool) JS::GetWeakMapEntry(JSContext* cx, HandleObject mapObj, HandleObject key, MutableHandleValue rval) { CHECK_REQUEST(cx); assertSameCompartment(cx, key); rval.setUndefined(); ObjectValueMap* map = mapObj->as<WeakMapObject>().getMap(); if (!map) return true; if (ObjectValueMap::Ptr ptr = map->lookup(key)) { // Read barrier to prevent an incorrectly gray value from escaping the // weak map. See the comment before UnmarkGrayChildren in gc/Marking.cpp ExposeValueToActiveJS(ptr->value().get()); rval.set(ptr->value()); } return true; } JS_PUBLIC_API(bool) JS::SetWeakMapEntry(JSContext* cx, HandleObject mapObj, HandleObject key, HandleValue val) { CHECK_REQUEST(cx); assertSameCompartment(cx, key, val); Rooted<WeakMapObject*> rootedMap(cx, &mapObj->as<WeakMapObject>()); return SetWeakMapEntryInternal(cx, rootedMap, key, val); } static bool WeakMap_construct(JSContext* cx, unsigned argc, Value* vp) { CallArgs args = CallArgsFromVp(argc, vp); // ES6 draft rev 31 (15 Jan 2015) 23.3.1.1 step 1. if (!ThrowIfNotConstructing(cx, args, "WeakMap")) return false; RootedObject newTarget(cx, &args.newTarget().toObject()); RootedObject obj(cx, CreateThis(cx, &WeakMapObject::class_, newTarget)); if (!obj) return false; // Steps 5-6, 11. if (!args.get(0).isNullOrUndefined()) { FixedInvokeArgs<1> args2(cx); args2[0].set(args[0]); RootedValue thisv(cx, ObjectValue(*obj)); if (!CallSelfHostedFunction(cx, cx->names().WeakMapConstructorInit, thisv, args2, args2.rval())) return false; } args.rval().setObject(*obj); return true; } static const ClassOps WeakMapObjectClassOps = { nullptr, /* addProperty */ nullptr, /* delProperty */ nullptr, /* getProperty */ nullptr, /* setProperty */ nullptr, /* enumerate */ nullptr, /* resolve */ nullptr, /* mayResolve */ WeakMap_finalize, nullptr, /* call */ nullptr, /* hasInstance */ nullptr, /* construct */ WeakMap_mark }; const Class WeakMapObject::class_ = { "WeakMap", JSCLASS_HAS_PRIVATE | JSCLASS_HAS_CACHED_PROTO(JSProto_WeakMap) | JSCLASS_BACKGROUND_FINALIZE, &WeakMapObjectClassOps }; static const JSFunctionSpec weak_map_methods[] = { JS_FN("has", WeakMap_has, 1, 0), JS_FN("get", WeakMap_get, 1, 0), JS_FN("delete", WeakMap_delete, 1, 0), JS_FN("set", WeakMap_set, 2, 0), JS_FS_END }; static JSObject* InitWeakMapClass(JSContext* cx, HandleObject obj, bool defineMembers) { MOZ_ASSERT(obj->isNative()); Rooted<GlobalObject*> global(cx, &obj->as<GlobalObject>()); RootedPlainObject proto(cx, NewBuiltinClassInstance<PlainObject>(cx)); if (!proto) return nullptr; RootedFunction ctor(cx, global->createConstructor(cx, WeakMap_construct, cx->names().WeakMap, 0)); if (!ctor) return nullptr; if (!LinkConstructorAndPrototype(cx, ctor, proto)) return nullptr; if (defineMembers) { if (!DefinePropertiesAndFunctions(cx, proto, nullptr, weak_map_methods)) return nullptr; if (!DefineToStringTag(cx, proto, cx->names().WeakMap)) return nullptr; } if (!GlobalObject::initBuiltinConstructor(cx, global, JSProto_WeakMap, ctor, proto)) return nullptr; return proto; } JSObject* js::InitWeakMapClass(JSContext* cx, HandleObject obj) { return InitWeakMapClass(cx, obj, true); } JSObject* js::InitBareWeakMapCtor(JSContext* cx, HandleObject obj) { return InitWeakMapClass(cx, obj, false); }