1 files changed, 324 insertions, 0 deletions
diff --git a/js/src/builtin/WeakMapObject.cpp b/js/src/builtin/WeakMapObject.cpp
new file mode 100644
index 0000000000..680f49bc3e
--- /dev/null
+++ b/js/src/builtin/WeakMapObject.cpp
@@ -0,0 +1,324 @@
+/* -*- 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 "builtin/WeakMapObject-inl.h"
+
+#include "builtin/WeakSetObject.h"
+#include "gc/GC.h"
+#include "gc/GCContext.h"
+#include "js/friend/ErrorMessages.h"  // JSMSG_*
+#include "js/PropertySpec.h"
+#include "js/WeakMap.h"
+#include "vm/Compartment.h"
+#include "vm/JSContext.h"
+#include "vm/SelfHosting.h"
+
+#include "gc/GCContext-inl.h"
+#include "gc/WeakMap-inl.h"
+#include "vm/NativeObject-inl.h"
+
+using namespace js;
+
+/* static */ MOZ_ALWAYS_INLINE bool WeakMapObject::is(HandleValue v) {
+  return v.isObject() && v.toObject().is<WeakMapObject>();
+}
+
+/* static */ MOZ_ALWAYS_INLINE bool WeakMapObject::has_impl(
+    JSContext* cx, const CallArgs& args) {
+  MOZ_ASSERT(is(args.thisv()));
+
+  if (!CanBeHeldWeakly(cx, args.get(0))) {
+    args.rval().setBoolean(false);
+    return true;
+  }
+
+  if (ValueValueWeakMap* map =
+          args.thisv().toObject().as<WeakMapObject>().getMap()) {
+    Value key = args[0];
+    if (map->has(key)) {
+      args.rval().setBoolean(true);
+      return true;
+    }
+  }
+
+  args.rval().setBoolean(false);
+  return true;
+}
+
+/* static */
+bool WeakMapObject::has(JSContext* cx, unsigned argc, Value* vp) {
+  CallArgs args = CallArgsFromVp(argc, vp);
+  return CallNonGenericMethod<WeakMapObject::is, WeakMapObject::has_impl>(cx,
+                                                                          args);
+}
+
+/* static */ MOZ_ALWAYS_INLINE bool WeakMapObject::get_impl(
+    JSContext* cx, const CallArgs& args) {
+  MOZ_ASSERT(WeakMapObject::is(args.thisv()));
+
+  if (!CanBeHeldWeakly(cx, args.get(0))) {
+    args.rval().setUndefined();
+    return true;
+  }
+
+  if (ValueValueWeakMap* map =
+          args.thisv().toObject().as<WeakMapObject>().getMap()) {
+    Value key = args[0];
+    if (ValueValueWeakMap::Ptr ptr = map->lookup(key)) {
+      args.rval().set(ptr->value());
+      return true;
+    }
+  }
+
+  args.rval().setUndefined();
+  return true;
+}
+
+/* static */
+bool WeakMapObject::get(JSContext* cx, unsigned argc, Value* vp) {
+  CallArgs args = CallArgsFromVp(argc, vp);
+  return CallNonGenericMethod<WeakMapObject::is, WeakMapObject::get_impl>(cx,
+                                                                          args);
+}
+
+/* static */ MOZ_ALWAYS_INLINE bool WeakMapObject::delete_impl(
+    JSContext* cx, const CallArgs& args) {
+  MOZ_ASSERT(WeakMapObject::is(args.thisv()));
+
+  if (!CanBeHeldWeakly(cx, args.get(0))) {
+    args.rval().setBoolean(false);
+    return true;
+  }
+
+  if (ValueValueWeakMap* map =
+          args.thisv().toObject().as<WeakMapObject>().getMap()) {
+    Value key = args[0];
+    // The lookup here is only used for the removal, so we can skip the read
+    // barrier. This is not very important for performance, but makes it easier
+    // to test nonbarriered removal from internal weakmaps (eg Debugger maps.)
+    if (ValueValueWeakMap::Ptr ptr = map->lookupUnbarriered(key)) {
+      map->remove(ptr);
+      args.rval().setBoolean(true);
+      return true;
+    }
+  }
+
+  args.rval().setBoolean(false);
+  return true;
+}
+
+/* static */
+bool WeakMapObject::delete_(JSContext* cx, unsigned argc, Value* vp) {
+  CallArgs args = CallArgsFromVp(argc, vp);
+  return CallNonGenericMethod<WeakMapObject::is, WeakMapObject::delete_impl>(
+      cx, args);
+}
+
+/* static */ MOZ_ALWAYS_INLINE bool WeakMapObject::set_impl(
+    JSContext* cx, const CallArgs& args) {
+  MOZ_ASSERT(WeakMapObject::is(args.thisv()));
+
+  if (!CanBeHeldWeakly(cx, args.get(0))) {
+    ReportValueError(cx, JSMSG_WEAKMAP_KEY_CANT_BE_HELD_WEAKLY,
+                     JSDVG_IGNORE_STACK, args.get(0), nullptr);
+    return false;
+  }
+
+  Rooted<WeakMapObject*> map(cx, &args.thisv().toObject().as<WeakMapObject>());
+
+  if (!WeakCollectionPutEntryInternal(cx, map, args[0], args.get(1))) {
+    return false;
+  }
+  args.rval().set(args.thisv());
+  return true;
+}
+
+/* static */
+bool WeakMapObject::set(JSContext* cx, unsigned argc, Value* vp) {
+  CallArgs args = CallArgsFromVp(argc, vp);
+  return CallNonGenericMethod<WeakMapObject::is, WeakMapObject::set_impl>(cx,
+                                                                          args);
+}
+
+size_t WeakCollectionObject::sizeOfExcludingThis(
+    mozilla::MallocSizeOf aMallocSizeOf) {
+  ValueValueWeakMap* map = getMap();
+  return map ? map->sizeOfIncludingThis(aMallocSizeOf) : 0;
+}
+
+bool WeakCollectionObject::nondeterministicGetKeys(
+    JSContext* cx, Handle<WeakCollectionObject*> obj, MutableHandleObject ret) {
+  RootedObject arr(cx, NewDenseEmptyArray(cx));
+  if (!arr) {
+    return false;
+  }
+  if (ValueValueWeakMap* map = obj->getMap()) {
+    // Prevent GC from mutating the weakmap while iterating.
+    gc::AutoSuppressGC suppress(cx);
+    for (ValueValueWeakMap::Base::Range r = map->all(); !r.empty();
+         r.popFront()) {
+      const auto& key = r.front().key();
+      MOZ_ASSERT(key.isObject() || key.isSymbol());
+      JS::ExposeValueToActiveJS(key);
+      RootedValue keyVal(cx, key);
+      if (!cx->compartment()->wrap(cx, &keyVal)) {
+        return false;
+      }
+      if (!NewbornArrayPush(cx, arr, keyVal)) {
+        return false;
+      }
+    }
+  }
+  ret.set(arr);
+  return true;
+}
+
+JS_PUBLIC_API bool JS_NondeterministicGetWeakMapKeys(JSContext* cx,
+                                                     HandleObject objArg,
+                                                     MutableHandleObject ret) {
+  RootedObject obj(cx, UncheckedUnwrap(objArg));
+  if (!obj || !obj->is<WeakMapObject>()) {
+    ret.set(nullptr);
+    return true;
+  }
+  return WeakCollectionObject::nondeterministicGetKeys(
+      cx, obj.as<WeakCollectionObject>(), ret);
+}
+
+static void WeakCollection_trace(JSTracer* trc, JSObject* obj) {
+  if (ValueValueWeakMap* map = obj->as<WeakCollectionObject>().getMap()) {
+    map->trace(trc);
+  }
+}
+
+static void WeakCollection_finalize(JS::GCContext* gcx, JSObject* obj) {
+  if (ValueValueWeakMap* map = obj->as<WeakCollectionObject>().getMap()) {
+    gcx->delete_(obj, map, MemoryUse::WeakMapObject);
+  }
+}
+
+JS_PUBLIC_API JSObject* JS::NewWeakMapObject(JSContext* cx) {
+  return NewBuiltinClassInstance<WeakMapObject>(cx);
+}
+
+JS_PUBLIC_API bool JS::IsWeakMapObject(JSObject* obj) {
+  return obj->is<WeakMapObject>();
+}
+
+JS_PUBLIC_API bool JS::GetWeakMapEntry(JSContext* cx, HandleObject mapObj,
+                                       HandleValue key,
+                                       MutableHandleValue rval) {
+  CHECK_THREAD(cx);
+  cx->check(key);
+  rval.setUndefined();
+
+  if (!CanBeHeldWeakly(cx, key)) {
+    return true;
+  }
+
+  ValueValueWeakMap* map = mapObj->as<WeakMapObject>().getMap();
+  if (!map) {
+    return true;
+  }
+
+  if (ValueValueWeakMap::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,
+                                       HandleValue key, HandleValue val) {
+  CHECK_THREAD(cx);
+  cx->check(key, val);
+  if (!CanBeHeldWeakly(cx, key)) {
+    ReportValueError(cx, JSMSG_WEAKMAP_KEY_CANT_BE_HELD_WEAKLY,
+                     JSDVG_IGNORE_STACK, key, nullptr);
+    return false;
+  }
+
+  Handle<WeakMapObject*> rootedMap = mapObj.as<WeakMapObject>();
+
+  return WeakCollectionPutEntryInternal(cx, rootedMap, key, val);
+}
+
+/* static */
+bool WeakMapObject::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 proto(cx);
+  if (!GetPrototypeFromBuiltinConstructor(cx, args, JSProto_WeakMap, &proto)) {
+    return false;
+  }
+
+  RootedObject obj(cx, NewObjectWithClassProto<WeakMapObject>(cx, proto));
+  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;
+}
+
+const JSClassOps WeakCollectionObject::classOps_ = {
+    nullptr,                  // addProperty
+    nullptr,                  // delProperty
+    nullptr,                  // enumerate
+    nullptr,                  // newEnumerate
+    nullptr,                  // resolve
+    nullptr,                  // mayResolve
+    WeakCollection_finalize,  // finalize
+    nullptr,                  // call
+    nullptr,                  // construct
+    WeakCollection_trace,     // trace
+};
+
+const ClassSpec WeakMapObject::classSpec_ = {
+    GenericCreateConstructor<WeakMapObject::construct, 0,
+                             gc::AllocKind::FUNCTION>,
+    GenericCreatePrototype<WeakMapObject>,
+    nullptr,
+    nullptr,
+    WeakMapObject::methods,
+    WeakMapObject::properties,
+};
+
+const JSClass WeakMapObject::class_ = {
+    "WeakMap",
+    JSCLASS_HAS_RESERVED_SLOTS(SlotCount) |
+        JSCLASS_HAS_CACHED_PROTO(JSProto_WeakMap) | JSCLASS_BACKGROUND_FINALIZE,
+    &WeakCollectionObject::classOps_, &WeakMapObject::classSpec_};
+
+const JSClass WeakMapObject::protoClass_ = {
+    "WeakMap.prototype", JSCLASS_HAS_CACHED_PROTO(JSProto_WeakMap),
+    JS_NULL_CLASS_OPS, &WeakMapObject::classSpec_};
+
+const JSPropertySpec WeakMapObject::properties[] = {
+    JS_STRING_SYM_PS(toStringTag, "WeakMap", JSPROP_READONLY), JS_PS_END};
+
+const JSFunctionSpec WeakMapObject::methods[] = {
+    JS_FN("has", has, 1, 0), JS_FN("get", get, 1, 0),
+    JS_FN("delete", delete_, 1, 0), JS_FN("set", set, 2, 0), JS_FS_END};