The Tor Browser: js/xpconnect/src/XPCWrappedNativeJSOps.cpp@b8a032363ba2 (annotated)

js/xpconnect/src/XPCWrappedNativeJSOps.cpp@b8a032363ba2 (annotated)

js/xpconnect/src/XPCWrappedNativeJSOps.cpp

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /* -*- 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/. */
 /* JavaScript JSClasses and JSOps for our Wrapped Native JS Objects. */
 #include "xpcprivate.h"
 #include "jsprf.h"
 #include "mozilla/dom/BindingUtils.h"
 #include "mozilla/Preferences.h"
 using namespace mozilla;
 using namespace JS;
 /***************************************************************************/
 // All of the exceptions thrown into JS from this file go through here.
 // That makes this a nice place to set a breakpoint.
 static bool Throw(nsresult errNum, JSContext* cx)
 {
     XPCThrower::Throw(errNum, cx);
     return false;
 }
 // Handy macro used in many callback stub below.
 #define THROW_AND_RETURN_IF_BAD_WRAPPER(cx, wrapper)                          \
     PR_BEGIN_MACRO                                                            \
     if (!wrapper)                                                             \
         return Throw(NS_ERROR_XPC_BAD_OP_ON_WN_PROTO, cx);                    \
     if (!wrapper->IsValid())                                                  \
         return Throw(NS_ERROR_XPC_HAS_BEEN_SHUTDOWN, cx);                     \
     PR_END_MACRO
 /***************************************************************************/
 static bool
 ToStringGuts(XPCCallContext& ccx)
 {
     char* sz;
     XPCWrappedNative* wrapper = ccx.GetWrapper();
     if (wrapper)
         sz = wrapper->ToString(ccx.GetTearOff());
     else
         sz = JS_smprintf("[xpconnect wrapped native prototype]");
     if (!sz) {
         JS_ReportOutOfMemory(ccx);
         return false;
     }
     JSString* str = JS_NewStringCopyZ(ccx, sz);
     JS_smprintf_free(sz);
     if (!str)
         return false;
     ccx.SetRetVal(STRING_TO_JSVAL(str));
     return true;
 }
 /***************************************************************************/
 static bool
 XPC_WN_Shared_ToString(JSContext *cx, unsigned argc, jsval *vp)
 {
     CallArgs args = CallArgsFromVp(argc, vp);
     RootedObject obj(cx, JS_THIS_OBJECT(cx, vp));
     if (!obj)
         return false;
     XPCCallContext ccx(JS_CALLER, cx, obj);
     if (!ccx.IsValid())
         return Throw(NS_ERROR_XPC_BAD_OP_ON_WN_PROTO, cx);
     ccx.SetName(ccx.GetRuntime()->GetStringID(XPCJSRuntime::IDX_TO_STRING));
     ccx.SetArgsAndResultPtr(args.length(), args.array(), vp);
     return ToStringGuts(ccx);
 }
 static bool
 XPC_WN_Shared_ToSource(JSContext *cx, unsigned argc, jsval *vp)
 {
     CallArgs args = CallArgsFromVp(argc, vp);
     static const char empty[] = "({})";
     JSString *str = JS_NewStringCopyN(cx, empty, sizeof(empty)-1);
     if (!str)
         return false;
     args.rval().setString(str);
     return true;
 }
 /***************************************************************************/
 // A "double wrapped object" is a user JSObject that has been wrapped as a
 // wrappedJS in order to be used by native code and then re-wrapped by a
 // wrappedNative wrapper to be used by JS code. One might think of it as:
 //    wrappedNative(wrappedJS(underlying_JSObject))
 // This is done (as opposed to just unwrapping the wrapped JS and automatically
 // returning the underlying JSObject) so that JS callers will see what looks
 // Like any other xpcom object - and be limited to use its interfaces.
 //
 // See the comment preceding nsIXPCWrappedJSObjectGetter in nsIXPConnect.idl.
 static JSObject*
 GetDoubleWrappedJSObject(XPCCallContext& ccx, XPCWrappedNative* wrapper)
 {
     RootedObject obj(ccx);
     nsCOMPtr<nsIXPConnectWrappedJS>
         underware = do_QueryInterface(wrapper->GetIdentityObject());
     if (underware) {
         RootedObject mainObj(ccx, underware->GetJSObject());
         if (mainObj) {
             RootedId id(ccx, ccx.GetRuntime()->
                             GetStringID(XPCJSRuntime::IDX_WRAPPED_JSOBJECT));
             JSAutoCompartment ac(ccx, mainObj);
             RootedValue val(ccx);
             if (JS_GetPropertyById(ccx, mainObj, id, &val) &&
                 !JSVAL_IS_PRIMITIVE(val)) {
                 obj = JSVAL_TO_OBJECT(val);
             }
         }
     }
     return obj;
 }
 // This is the getter native function we use to handle 'wrappedJSObject' for
 // double wrapped JSObjects.
 static bool
 XPC_WN_DoubleWrappedGetter(JSContext *cx, unsigned argc, jsval *vp)
 {
     CallArgs args = CallArgsFromVp(argc, vp);
     RootedObject obj(cx, JS_THIS_OBJECT(cx, vp));
     if (!obj)
         return false;
     XPCCallContext ccx(JS_CALLER, cx, obj);
     XPCWrappedNative* wrapper = ccx.GetWrapper();
     THROW_AND_RETURN_IF_BAD_WRAPPER(cx, wrapper);
     MOZ_ASSERT(JS_TypeOfValue(cx, args.calleev()) == JSTYPE_FUNCTION, "bad function");
     RootedObject realObject(cx, GetDoubleWrappedJSObject(ccx, wrapper));
     if (!realObject) {
         // This is pretty unexpected at this point. The object originally
         // responded to this get property call and now gives no object.
         // XXX Should this throw something at the caller?
         args.rval().setNull();
         return true;
     }
     // It is a double wrapped object. This should really never appear in
     // content these days, but addons still do it - see bug 965921.
     if (MOZ_UNLIKELY(!nsContentUtils::IsCallerChrome())) {
         JS_ReportError(cx, "Attempt to use .wrappedJSObject in untrusted code");
         return false;
     }
     args.rval().setObject(*realObject);
     return JS_WrapValue(cx, args.rval());
 }
 /***************************************************************************/
 // This is our shared function to define properties on our JSObjects.
 /*
  * NOTE:
  * We *never* set the tearoff names (e.g. nsIFoo) as JS_ENUMERATE.
  * We *never* set toString or toSource as JS_ENUMERATE.
  */
 static bool
 DefinePropertyIfFound(XPCCallContext& ccx,
                       HandleObject obj,
                       HandleId idArg,
                       XPCNativeSet* set,
                       XPCNativeInterface* iface,
                       XPCNativeMember* member,
                       XPCWrappedNativeScope* scope,
                       bool reflectToStringAndToSource,
                       XPCWrappedNative* wrapperToReflectInterfaceNames,
                       XPCWrappedNative* wrapperToReflectDoubleWrap,
                       XPCNativeScriptableInfo* scriptableInfo,
                       unsigned propFlags,
                       bool* resolved)
 {
     RootedId id(ccx, idArg);
     XPCJSRuntime* rt = ccx.GetRuntime();
     bool found;
     const char* name;
     if (set) {
         if (iface)
             found = true;
         else
             found = set->FindMember(id, &member, &iface);
     } else
         found = (nullptr != (member = iface->FindMember(id)));
     if (!found) {
         if (reflectToStringAndToSource) {
             JSNative call;
             uint32_t flags = 0;
             if (scriptableInfo) {
                 nsCOMPtr<nsIClassInfo> classInfo = do_QueryInterface(
                     scriptableInfo->GetCallback());
                 if (classInfo) {
                     nsresult rv = classInfo->GetFlags(&flags);
                     if (NS_FAILED(rv))
                         return Throw(rv, ccx);
                 }
             }
             bool overwriteToString = !(flags & nsIClassInfo::DOM_OBJECT)
                 || Preferences::GetBool("dom.XPCToStringForDOMClasses", false);
             if(id == rt->GetStringID(XPCJSRuntime::IDX_TO_STRING)
                 && overwriteToString)
             {
                 call = XPC_WN_Shared_ToString;
                 name = rt->GetStringName(XPCJSRuntime::IDX_TO_STRING);
                 id   = rt->GetStringID(XPCJSRuntime::IDX_TO_STRING);
             } else if (id == rt->GetStringID(XPCJSRuntime::IDX_TO_SOURCE)) {
                 call = XPC_WN_Shared_ToSource;
                 name = rt->GetStringName(XPCJSRuntime::IDX_TO_SOURCE);
                 id   = rt->GetStringID(XPCJSRuntime::IDX_TO_SOURCE);
             }
             else
                 call = nullptr;
             if (call) {
                 RootedFunction fun(ccx, JS_NewFunction(ccx, call, 0, 0, obj, name));
                 if (!fun) {
                     JS_ReportOutOfMemory(ccx);
                     return false;
                 }
                 AutoResolveName arn(ccx, id);
                 if (resolved)
                     *resolved = true;
                 return JS_DefinePropertyById(ccx, obj, id,
                                              OBJECT_TO_JSVAL(JS_GetFunctionObject(fun)),
                                              nullptr, nullptr,
                                              propFlags & ~JSPROP_ENUMERATE);
             }
         }
         // This *might* be a tearoff name that is not yet part of our
         // set. Let's lookup the name and see if it is the name of an
         // interface. Then we'll see if the object actually *does* this
         // interface and add a tearoff as necessary.
         if (wrapperToReflectInterfaceNames) {
             JSAutoByteString name;
             AutoMarkingNativeInterfacePtr iface2(ccx);
             XPCWrappedNativeTearOff* to;
             RootedObject jso(ccx);
             nsresult rv = NS_OK;
             if (JSID_IS_STRING(id) &&
                 name.encodeLatin1(ccx, JSID_TO_STRING(id)) &&
                 (iface2 = XPCNativeInterface::GetNewOrUsed(name.ptr()), iface2) &&
                 nullptr != (to = wrapperToReflectInterfaceNames->
                            FindTearOff(iface2, true, &rv)) &&
                 nullptr != (jso = to->GetJSObject()))
             {
                 AutoResolveName arn(ccx, id);
                 if (resolved)
                     *resolved = true;
                 return JS_DefinePropertyById(ccx, obj, id, OBJECT_TO_JSVAL(jso),
                                              nullptr, nullptr,
                                              propFlags & ~JSPROP_ENUMERATE);
             } else if (NS_FAILED(rv) && rv != NS_ERROR_NO_INTERFACE) {
                 return Throw(rv, ccx);
             }
         }
         // This *might* be a double wrapped JSObject
         if (wrapperToReflectDoubleWrap &&
             id == rt->GetStringID(XPCJSRuntime::IDX_WRAPPED_JSOBJECT) &&
             GetDoubleWrappedJSObject(ccx, wrapperToReflectDoubleWrap)) {
             // We build and add a getter function.
             // A security check is done on a per-get basis.
             JSFunction* fun;
             id = rt->GetStringID(XPCJSRuntime::IDX_WRAPPED_JSOBJECT);
             name = rt->GetStringName(XPCJSRuntime::IDX_WRAPPED_JSOBJECT);
             fun = JS_NewFunction(ccx, XPC_WN_DoubleWrappedGetter,
 , 0, obj, name);
             if (!fun)
                 return false;
             RootedObject funobj(ccx, JS_GetFunctionObject(fun));
             if (!funobj)
                 return false;
             propFlags |= JSPROP_GETTER | JSPROP_SHARED;
             propFlags &= ~JSPROP_ENUMERATE;
             AutoResolveName arn(ccx, id);
             if (resolved)
                 *resolved = true;
             return JS_DefinePropertyById(ccx, obj, id, JSVAL_VOID,
                                          JS_DATA_TO_FUNC_PTR(JSPropertyOp,
                                                              funobj.get()),
                                          nullptr, propFlags);
         }
         if (resolved)
             *resolved = false;
         return true;
     }
     if (!member) {
         if (wrapperToReflectInterfaceNames) {
             XPCWrappedNativeTearOff* to =
               wrapperToReflectInterfaceNames->FindTearOff(iface, true);
             if (!to)
                 return false;
             RootedObject jso(ccx, to->GetJSObject());
             if (!jso)
                 return false;
             AutoResolveName arn(ccx, id);
             if (resolved)
                 *resolved = true;
             return JS_DefinePropertyById(ccx, obj, id, OBJECT_TO_JSVAL(jso),
                                          nullptr, nullptr,
                                          propFlags & ~JSPROP_ENUMERATE);
         }
         if (resolved)
             *resolved = false;
         return true;
     }
     if (member->IsConstant()) {
         RootedValue val(ccx);
         AutoResolveName arn(ccx, id);
         if (resolved)
             *resolved = true;
         return member->GetConstantValue(ccx, iface, val.address()) &&
                JS_DefinePropertyById(ccx, obj, id, val, nullptr, nullptr,
                                      propFlags);
     }
     if (id == rt->GetStringID(XPCJSRuntime::IDX_TO_STRING) ||
         id == rt->GetStringID(XPCJSRuntime::IDX_TO_SOURCE) ||
         (scriptableInfo &&
          scriptableInfo->GetFlags().DontEnumQueryInterface() &&
          id == rt->GetStringID(XPCJSRuntime::IDX_QUERY_INTERFACE)))
         propFlags &= ~JSPROP_ENUMERATE;
     RootedValue funval(ccx);
     if (!member->NewFunctionObject(ccx, iface, obj, funval.address()))
         return false;
     if (member->IsMethod()) {
         AutoResolveName arn(ccx, id);
         if (resolved)
             *resolved = true;
         return JS_DefinePropertyById(ccx, obj, id, funval, nullptr, nullptr,
                                      propFlags);
     }
     // else...
     MOZ_ASSERT(member->IsAttribute(), "way broken!");
     propFlags |= JSPROP_GETTER | JSPROP_SHARED;
     JSObject* funobj = JSVAL_TO_OBJECT(funval);
     JSPropertyOp getter = JS_DATA_TO_FUNC_PTR(JSPropertyOp, funobj);
     JSStrictPropertyOp setter;
     if (member->IsWritableAttribute()) {
         propFlags |= JSPROP_SETTER;
         propFlags &= ~JSPROP_READONLY;
         setter = JS_DATA_TO_FUNC_PTR(JSStrictPropertyOp, funobj);
     } else {
         setter = js_GetterOnlyPropertyStub;
     }
     AutoResolveName arn(ccx, id);
     if (resolved)
         *resolved = true;
     return JS_DefinePropertyById(ccx, obj, id, JSVAL_VOID, getter, setter,
                                  propFlags);
 }
 /***************************************************************************/
 /***************************************************************************/
 static bool
 XPC_WN_OnlyIWrite_AddPropertyStub(JSContext *cx, HandleObject obj, HandleId id, MutableHandleValue vp)
 {
     XPCCallContext ccx(JS_CALLER, cx, obj, NullPtr(), id);
     XPCWrappedNative* wrapper = ccx.GetWrapper();
     THROW_AND_RETURN_IF_BAD_WRAPPER(cx, wrapper);
     // Allow only XPConnect to add/set the property
     if (ccx.GetResolveName() == id)
         return true;
     return Throw(NS_ERROR_XPC_CANT_MODIFY_PROP_ON_WN, cx);
 }
 static bool
 XPC_WN_OnlyIWrite_SetPropertyStub(JSContext *cx, HandleObject obj, HandleId id, bool strict,
                                   MutableHandleValue vp)
 {
     return XPC_WN_OnlyIWrite_AddPropertyStub(cx, obj, id, vp);
 }
 static bool
 XPC_WN_CannotModifyPropertyStub(JSContext *cx, HandleObject obj, HandleId id,
                                 MutableHandleValue vp)
 {
     return Throw(NS_ERROR_XPC_CANT_MODIFY_PROP_ON_WN, cx);
 }
 static bool
 XPC_WN_CantDeletePropertyStub(JSContext *cx, HandleObject obj, HandleId id,
                               bool *succeeded)
 {
     return Throw(NS_ERROR_XPC_CANT_MODIFY_PROP_ON_WN, cx);
 }
 static bool
 XPC_WN_CannotModifyStrictPropertyStub(JSContext *cx, HandleObject obj, HandleId id, bool strict,
                                       MutableHandleValue vp)
 {
     return XPC_WN_CannotModifyPropertyStub(cx, obj, id, vp);
 }
 static bool
 XPC_WN_Shared_Convert(JSContext *cx, HandleObject obj, JSType type, MutableHandleValue vp)
 {
     if (type == JSTYPE_OBJECT) {
         vp.set(OBJECT_TO_JSVAL(obj));
         return true;
     }
     XPCCallContext ccx(JS_CALLER, cx, obj);
     XPCWrappedNative* wrapper = ccx.GetWrapper();
     THROW_AND_RETURN_IF_BAD_WRAPPER(cx, wrapper);
     switch (type) {
         case JSTYPE_FUNCTION:
             {
                 if (!ccx.GetTearOff()) {
                     XPCNativeScriptableInfo* si = wrapper->GetScriptableInfo();
                     if (si && (si->GetFlags().WantCall() ||
                                si->GetFlags().WantConstruct())) {
                         vp.set(OBJECT_TO_JSVAL(obj));
                         return true;
                     }
                 }
             }
             return Throw(NS_ERROR_XPC_CANT_CONVERT_WN_TO_FUN, cx);
         case JSTYPE_NUMBER:
             vp.set(JS_GetNaNValue(cx));
             return true;
         case JSTYPE_BOOLEAN:
             vp.set(JSVAL_TRUE);
             return true;
         case JSTYPE_VOID:
         case JSTYPE_STRING:
         {
             ccx.SetName(ccx.GetRuntime()->GetStringID(XPCJSRuntime::IDX_TO_STRING));
             ccx.SetArgsAndResultPtr(0, nullptr, vp.address());
             XPCNativeMember* member = ccx.GetMember();
             if (member && member->IsMethod()) {
                 if (!XPCWrappedNative::CallMethod(ccx))
                     return false;
                 if (JSVAL_IS_PRIMITIVE(vp))
                     return true;
             }
             // else...
             return ToStringGuts(ccx);
         }
         default:
             NS_ERROR("bad type in conversion");
             return false;
     }
     NS_NOTREACHED("huh?");
     return false;
 }
 static bool
 XPC_WN_Shared_Enumerate(JSContext *cx, HandleObject obj)
 {
     XPCCallContext ccx(JS_CALLER, cx, obj);
     XPCWrappedNative* wrapper = ccx.GetWrapper();
     THROW_AND_RETURN_IF_BAD_WRAPPER(cx, wrapper);
     // Since we aren't going to enumerate tearoff names and the prototype
     // handles non-mutated members, we can do this potential short-circuit.
     if (!wrapper->HasMutatedSet())
         return true;
     XPCNativeSet* set = wrapper->GetSet();
     XPCNativeSet* protoSet = wrapper->HasProto() ?
                                 wrapper->GetProto()->GetSet() : nullptr;
     uint16_t interface_count = set->GetInterfaceCount();
     XPCNativeInterface** interfaceArray = set->GetInterfaceArray();
     for (uint16_t i = 0; i < interface_count; i++) {
         XPCNativeInterface* iface = interfaceArray[i];
         uint16_t member_count = iface->GetMemberCount();
         for (uint16_t k = 0; k < member_count; k++) {
             XPCNativeMember* member = iface->GetMemberAt(k);
             jsid name = member->GetName();
             // Skip if this member is going to come from the proto.
             uint16_t index;
             if (protoSet &&
                 protoSet->FindMember(name, nullptr, &index) && index == i)
                 continue;
             if (!xpc_ForcePropertyResolve(cx, obj, name))
                 return false;
         }
     }
     return true;
 }
 /***************************************************************************/
 enum WNHelperType {
     WN_NOHELPER,
     WN_HELPER
 };
 static void
 WrappedNativeFinalize(js::FreeOp *fop, JSObject *obj, WNHelperType helperType)
 {
     const js::Class* clazz = js::GetObjectClass(obj);
     if (clazz->flags & JSCLASS_DOM_GLOBAL) {
         mozilla::dom::DestroyProtoAndIfaceCache(obj);
     }
     nsISupports* p = static_cast<nsISupports*>(xpc_GetJSPrivate(obj));
     if (!p)
         return;
     XPCWrappedNative* wrapper = static_cast<XPCWrappedNative*>(p);
     if (helperType == WN_HELPER)
         wrapper->GetScriptableCallback()->Finalize(wrapper, js::CastToJSFreeOp(fop), obj);
     wrapper->FlatJSObjectFinalized();
 }
 static void
 XPC_WN_NoHelper_Finalize(js::FreeOp *fop, JSObject *obj)
 {
     WrappedNativeFinalize(fop, obj, WN_NOHELPER);
 }
 /*
  * General comment about XPConnect tracing: Given a C++ object |wrapper| and its
  * corresponding JS object |obj|, calling |wrapper->TraceSelf| will ask the JS
  * engine to mark |obj|. Eventually, this will lead to the trace hook being
  * called for |obj|. The trace hook should call |wrapper->TraceInside|, which
  * should mark any JS objects held by |wrapper| as members.
  */
 static void
 MarkWrappedNative(JSTracer *trc, JSObject *obj)
 {
     const js::Class* clazz = js::GetObjectClass(obj);
     if (clazz->flags & JSCLASS_DOM_GLOBAL) {
         mozilla::dom::TraceProtoAndIfaceCache(trc, obj);
     }
     MOZ_ASSERT(IS_WN_CLASS(clazz));
     XPCWrappedNative *wrapper = XPCWrappedNative::Get(obj);
     if (wrapper && wrapper->IsValid())
         wrapper->TraceInside(trc);
 }
 /* static */ void
 XPCWrappedNative::Trace(JSTracer *trc, JSObject *obj)
 {
     MarkWrappedNative(trc, obj);
 }
 static bool
 XPC_WN_NoHelper_Resolve(JSContext *cx, HandleObject obj, HandleId id)
 {
     XPCCallContext ccx(JS_CALLER, cx, obj, NullPtr(), id);
     XPCWrappedNative* wrapper = ccx.GetWrapper();
     THROW_AND_RETURN_IF_BAD_WRAPPER(cx, wrapper);
     XPCNativeSet* set = ccx.GetSet();
     if (!set)
         return true;
     // Don't resolve properties that are on our prototype.
     if (ccx.GetInterface() && !ccx.GetStaticMemberIsLocal())
         return true;
     return DefinePropertyIfFound(ccx, obj, id,
                                  set, nullptr, nullptr, wrapper->GetScope(),
                                  true, wrapper, wrapper, nullptr,
                                  JSPROP_ENUMERATE |
                                  JSPROP_READONLY |
                                  JSPROP_PERMANENT, nullptr);
 }
 static JSObject *
 XPC_WN_OuterObject(JSContext *cx, HandleObject objArg)
 {
     JSObject *obj = objArg;
     XPCWrappedNative *wrapper = XPCWrappedNative::Get(obj);
     if (!wrapper) {
         Throw(NS_ERROR_XPC_BAD_OP_ON_WN_PROTO, cx);
         return nullptr;
     }
     if (!wrapper->IsValid()) {
         Throw(NS_ERROR_XPC_HAS_BEEN_SHUTDOWN, cx);
         return nullptr;
     }
     XPCNativeScriptableInfo* si = wrapper->GetScriptableInfo();
     if (si && si->GetFlags().WantOuterObject()) {
         RootedObject newThis(cx);
         nsresult rv =
             si->GetCallback()->OuterObject(wrapper, cx, obj, newThis.address());
         if (NS_FAILED(rv)) {
             Throw(rv, cx);
             return nullptr;
         }
         obj = newThis;
     }
     return obj;
 }
 const XPCWrappedNativeJSClass XPC_WN_NoHelper_JSClass = {
   { // base
     "XPCWrappedNative_NoHelper",    // name;
     WRAPPER_SLOTS |
     JSCLASS_PRIVATE_IS_NSISUPPORTS, // flags
     /* Mandatory non-null function pointer members. */
     XPC_WN_OnlyIWrite_AddPropertyStub, // addProperty
     XPC_WN_CantDeletePropertyStub,     // delProperty
     JS_PropertyStub,                   // getProperty
     XPC_WN_OnlyIWrite_SetPropertyStub, // setProperty
     XPC_WN_Shared_Enumerate,           // enumerate
     XPC_WN_NoHelper_Resolve,           // resolve
     XPC_WN_Shared_Convert,             // convert
     XPC_WN_NoHelper_Finalize,          // finalize
     /* Optionally non-null members start here. */
     nullptr,                         // call
     nullptr,                         // construct
     nullptr,                         // hasInstance
     XPCWrappedNative::Trace,         // trace
     JS_NULL_CLASS_SPEC,
     // ClassExtension
     {
         nullptr, // outerObject
         nullptr, // innerObject
         nullptr, // iteratorObject
         true,   // isWrappedNative
     },
     // ObjectOps
     {
         nullptr, // lookupGeneric
         nullptr, // lookupProperty
         nullptr, // lookupElement
         nullptr, // defineGeneric
         nullptr, // defineProperty
         nullptr, // defineElement
         nullptr, // getGeneric
         nullptr, // getProperty
         nullptr, // getElement
         nullptr, // setGeneric
         nullptr, // setProperty
         nullptr, // setElement
         nullptr, // getGenericAttributes
         nullptr, // setGenericAttributes
         nullptr, // deleteProperty
         nullptr, // deleteElement
         nullptr, nullptr, // watch/unwatch
         nullptr, // slice
         XPC_WN_JSOp_Enumerate,
         XPC_WN_JSOp_ThisObject,
     }
   },
 // interfacesBitmap
 };
 /***************************************************************************/
 static bool
 XPC_WN_MaybeResolvingPropertyStub(JSContext *cx, HandleObject obj, HandleId id, MutableHandleValue vp)
 {
     XPCCallContext ccx(JS_CALLER, cx, obj);
     XPCWrappedNative* wrapper = ccx.GetWrapper();
     THROW_AND_RETURN_IF_BAD_WRAPPER(cx, wrapper);
     if (ccx.GetResolvingWrapper() == wrapper)
         return true;
     return Throw(NS_ERROR_XPC_CANT_MODIFY_PROP_ON_WN, cx);
 }
 static bool
 XPC_WN_MaybeResolvingStrictPropertyStub(JSContext *cx, HandleObject obj, HandleId id, bool strict,
                                         MutableHandleValue vp)
 {
     return XPC_WN_MaybeResolvingPropertyStub(cx, obj, id, vp);
 }
 static bool
 XPC_WN_MaybeResolvingDeletePropertyStub(JSContext *cx, HandleObject obj, HandleId id, bool *succeeded)
 {
     XPCCallContext ccx(JS_CALLER, cx, obj);
     XPCWrappedNative* wrapper = ccx.GetWrapper();
     THROW_AND_RETURN_IF_BAD_WRAPPER(cx, wrapper);
     if (ccx.GetResolvingWrapper() == wrapper) {
         *succeeded = true;
         return true;
     }
     return Throw(NS_ERROR_XPC_CANT_MODIFY_PROP_ON_WN, cx);
 }
 // macro fun!
 #define PRE_HELPER_STUB                                                       \
     JSObject *unwrapped = js::CheckedUnwrap(obj, false);                      \
     if (!unwrapped) {                                                         \
         JS_ReportError(cx, "Permission denied to operate on object.");        \
         return false;                                                         \
     }                                                                         \
     if (!IS_WN_REFLECTOR(unwrapped)) {                                        \
         return Throw(NS_ERROR_XPC_BAD_OP_ON_WN_PROTO, cx);                    \
     }                                                                         \
     XPCWrappedNative *wrapper = XPCWrappedNative::Get(unwrapped);             \
     THROW_AND_RETURN_IF_BAD_WRAPPER(cx, wrapper);                             \
     bool retval = true;                                                       \
     nsresult rv = wrapper->GetScriptableCallback()->
 #define POST_HELPER_STUB                                                      \
     if (NS_FAILED(rv))                                                        \
         return Throw(rv, cx);                                                 \
     return retval;
 static bool
 XPC_WN_Helper_AddProperty(JSContext *cx, HandleObject obj, HandleId id,
                           MutableHandleValue vp)
 {
     PRE_HELPER_STUB
     AddProperty(wrapper, cx, obj, id, vp.address(), &retval);
     POST_HELPER_STUB
 }
 static bool
 XPC_WN_Helper_DelProperty(JSContext *cx, HandleObject obj, HandleId id,
                           bool *succeeded)
 {
     *succeeded = true;
     PRE_HELPER_STUB
     DelProperty(wrapper, cx, obj, id, &retval);
     POST_HELPER_STUB
 }
 bool
 XPC_WN_Helper_GetProperty(JSContext *cx, HandleObject obj, HandleId id,
                           MutableHandleValue vp)
 {
     PRE_HELPER_STUB
     GetProperty(wrapper, cx, obj, id, vp.address(), &retval);
     POST_HELPER_STUB
 }
 bool
 XPC_WN_Helper_SetProperty(JSContext *cx, HandleObject obj, HandleId id, bool strict,
                           MutableHandleValue vp)
 {
     PRE_HELPER_STUB
     SetProperty(wrapper, cx, obj, id, vp.address(), &retval);
     POST_HELPER_STUB
 }
 static bool
 XPC_WN_Helper_Convert(JSContext *cx, HandleObject obj, JSType type, MutableHandleValue vp)
 {
     PRE_HELPER_STUB
     Convert(wrapper, cx, obj, type, vp.address(), &retval);
     POST_HELPER_STUB
 }
 static bool
 XPC_WN_Helper_Call(JSContext *cx, unsigned argc, jsval *vp)
 {
     JS::CallArgs args = JS::CallArgsFromVp(argc, vp);
     // N.B. we want obj to be the callee, not JS_THIS(cx, vp)
     RootedObject obj(cx, &args.callee());
     XPCCallContext ccx(JS_CALLER, cx, obj, NullPtr(), JSID_VOIDHANDLE, args.length(),
                        args.array(), args.rval().address());
     if (!ccx.IsValid())
         return false;
     MOZ_ASSERT(obj == ccx.GetFlattenedJSObject());
     PRE_HELPER_STUB
     Call(wrapper, cx, obj, args, &retval);
     POST_HELPER_STUB
 }
 static bool
 XPC_WN_Helper_Construct(JSContext *cx, unsigned argc, jsval *vp)
 {
     JS::CallArgs args = JS::CallArgsFromVp(argc, vp);
     RootedObject obj(cx, &args.callee());
     if (!obj)
         return false;
     XPCCallContext ccx(JS_CALLER, cx, obj, NullPtr(), JSID_VOIDHANDLE, args.length(),
                        args.array(), args.rval().address());
     if (!ccx.IsValid())
         return false;
     MOZ_ASSERT(obj == ccx.GetFlattenedJSObject());
     PRE_HELPER_STUB
     Construct(wrapper, cx, obj, args, &retval);
     POST_HELPER_STUB
 }
 static bool
 XPC_WN_Helper_HasInstance(JSContext *cx, HandleObject obj, MutableHandleValue valp, bool *bp)
 {
     bool retval2;
     PRE_HELPER_STUB
     HasInstance(wrapper, cx, obj, valp, &retval2, &retval);
     *bp = retval2;
     POST_HELPER_STUB
 }
 static void
 XPC_WN_Helper_Finalize(js::FreeOp *fop, JSObject *obj)
 {
     WrappedNativeFinalize(fop, obj, WN_HELPER);
 }
 static bool
 XPC_WN_Helper_NewResolve(JSContext *cx, HandleObject obj, HandleId id,
                          MutableHandleObject objp)
 {
     nsresult rv = NS_OK;
     bool retval = true;
     RootedObject obj2FromScriptable(cx);
     XPCCallContext ccx(JS_CALLER, cx, obj);
     XPCWrappedNative* wrapper = ccx.GetWrapper();
     THROW_AND_RETURN_IF_BAD_WRAPPER(cx, wrapper);
     RootedId old(cx, ccx.SetResolveName(id));
     XPCNativeScriptableInfo* si = wrapper->GetScriptableInfo();
     if (si && si->GetFlags().WantNewResolve()) {
         XPCWrappedNative* oldResolvingWrapper;
         bool allowPropMods = si->GetFlags().AllowPropModsDuringResolve();
         if (allowPropMods)
             oldResolvingWrapper = ccx.SetResolvingWrapper(wrapper);
         rv = si->GetCallback()->NewResolve(wrapper, cx, obj, id,
                                            obj2FromScriptable.address(), &retval);
         if (allowPropMods)
             (void)ccx.SetResolvingWrapper(oldResolvingWrapper);
     }
     old = ccx.SetResolveName(old);
     MOZ_ASSERT(old == id, "bad nest");
     if (NS_FAILED(rv)) {
         return Throw(rv, cx);
     }
     if (obj2FromScriptable) {
         objp.set(obj2FromScriptable);
     } else if (wrapper->HasMutatedSet()) {
         // We are here if scriptable did not resolve this property and
         // it *might* be in the instance set but not the proto set.
         XPCNativeSet* set = wrapper->GetSet();
         XPCNativeSet* protoSet = wrapper->HasProto() ?
                                     wrapper->GetProto()->GetSet() : nullptr;
         XPCNativeMember* member;
         XPCNativeInterface* iface;
         bool IsLocal;
         if (set->FindMember(id, &member, &iface, protoSet, &IsLocal) &&
             IsLocal) {
             XPCWrappedNative* oldResolvingWrapper;
             XPCNativeScriptableFlags siFlags(0);
             if (si)
                 siFlags = si->GetFlags();
             unsigned enumFlag =
                 siFlags.DontEnumStaticProps() ? 0 : JSPROP_ENUMERATE;
             XPCWrappedNative* wrapperForInterfaceNames =
                 siFlags.DontReflectInterfaceNames() ? nullptr : wrapper;
             bool resolved;
             oldResolvingWrapper = ccx.SetResolvingWrapper(wrapper);
             retval = DefinePropertyIfFound(ccx, obj, id,
                                            set, iface, member,
                                            wrapper->GetScope(),
                                            false,
                                            wrapperForInterfaceNames,
                                            nullptr, si,
                                            enumFlag, &resolved);
             (void)ccx.SetResolvingWrapper(oldResolvingWrapper);
             if (retval && resolved)
                 objp.set(obj);
         }
     }
     return retval;
 }
 /***************************************************************************/
 /*
     Here are the enumerator cases:
     set jsclass enumerate to stub (unless noted otherwise)
     if ( helper wants new enumerate )
         if ( DONT_ENUM_STATICS )
             forward to scriptable enumerate
         else
             if ( set not mutated )
                 forward to scriptable enumerate
             else
                 call shared enumerate
                 forward to scriptable enumerate
     else if ( helper wants old enumerate )
         use this JSOp
         if ( DONT_ENUM_STATICS )
             call scriptable enumerate
             call stub
         else
             if ( set not mutated )
                 call scriptable enumerate
                 call stub
             else
                 call shared enumerate
                 call scriptable enumerate
                 call stub
     else //... if ( helper wants NO enumerate )
         if ( DONT_ENUM_STATICS )
             use enumerate stub - don't use this JSOp thing at all
         else
             do shared enumerate - don't use this JSOp thing at all
 */
 bool
 XPC_WN_JSOp_Enumerate(JSContext *cx, HandleObject obj, JSIterateOp enum_op,
                       MutableHandleValue statep, MutableHandleId idp)
 {
     const js::Class *clazz = js::GetObjectClass(obj);
     if (!IS_WN_CLASS(clazz) || clazz == &XPC_WN_NoHelper_JSClass.base) {
         // obj must be a prototype object or a wrapper w/o a
         // helper. Short circuit this call to the default
         // implementation.
         return JS_EnumerateState(cx, obj, enum_op, statep, idp);
     }
     XPCCallContext ccx(JS_CALLER, cx, obj);
     XPCWrappedNative* wrapper = ccx.GetWrapper();
     THROW_AND_RETURN_IF_BAD_WRAPPER(cx, wrapper);
     XPCNativeScriptableInfo* si = wrapper->GetScriptableInfo();
     if (!si)
         return Throw(NS_ERROR_XPC_BAD_OP_ON_WN_PROTO, cx);
     bool retval = true;
     nsresult rv;
     if (si->GetFlags().WantNewEnumerate()) {
         if (((enum_op == JSENUMERATE_INIT &&
               !si->GetFlags().DontEnumStaticProps()) ||
              enum_op == JSENUMERATE_INIT_ALL) &&
             wrapper->HasMutatedSet() &&
             !XPC_WN_Shared_Enumerate(cx, obj)) {
             statep.set(JSVAL_NULL);
             return false;
         }
         // XXX Might we really need to wrap this call and *also* call
         // js_ObjectOps.enumerate ???
         rv = si->GetCallback()->
             NewEnumerate(wrapper, cx, obj, enum_op, statep.address(), idp.address(), &retval);
         if ((enum_op == JSENUMERATE_INIT || enum_op == JSENUMERATE_INIT_ALL) &&
             (NS_FAILED(rv) || !retval)) {
             statep.set(JSVAL_NULL);
         }
         if (NS_FAILED(rv))
             return Throw(rv, cx);
         return retval;
     }
     if (si->GetFlags().WantEnumerate()) {
         if (enum_op == JSENUMERATE_INIT || enum_op == JSENUMERATE_INIT_ALL) {
             if ((enum_op == JSENUMERATE_INIT_ALL ||
                  !si->GetFlags().DontEnumStaticProps()) &&
                 wrapper->HasMutatedSet() &&
                 !XPC_WN_Shared_Enumerate(cx, obj)) {
                 statep.set(JSVAL_NULL);
                 return false;
             }
             rv = si->GetCallback()->
                 Enumerate(wrapper, cx, obj, &retval);
             if (NS_FAILED(rv) || !retval)
                 statep.set(JSVAL_NULL);
             if (NS_FAILED(rv))
                 return Throw(rv, cx);
             if (!retval)
                 return false;
             // Then fall through and call the default implementation...
         }
     }
     // else call js_ObjectOps.enumerate...
     return JS_EnumerateState(cx, obj, enum_op, statep, idp);
 }
 JSObject*
 XPC_WN_JSOp_ThisObject(JSContext *cx, HandleObject obj)
 {
     return JS_ObjectToOuterObject(cx, obj);
 }
 /***************************************************************************/
 // static
 XPCNativeScriptableInfo*
 XPCNativeScriptableInfo::Construct(const XPCNativeScriptableCreateInfo* sci)
 {
     MOZ_ASSERT(sci, "bad param");
     MOZ_ASSERT(sci->GetCallback(), "bad param");
     XPCNativeScriptableInfo* newObj =
         new XPCNativeScriptableInfo(sci->GetCallback());
     if (!newObj)
         return nullptr;
     char* name = nullptr;
     if (NS_FAILED(sci->GetCallback()->GetClassName(&name)) || !name) {
         delete newObj;
         return nullptr;
     }
     bool success;
     XPCJSRuntime* rt = XPCJSRuntime::Get();
     XPCNativeScriptableSharedMap* map = rt->GetNativeScriptableSharedMap();
     success = map->GetNewOrUsed(sci->GetFlags(), name,
                                 sci->GetInterfacesBitmap(), newObj);
     if (!success) {
         delete newObj;
         return nullptr;
     }
     return newObj;
 }
 void
 XPCNativeScriptableShared::PopulateJSClass()
 {
     MOZ_ASSERT(mJSClass.base.name, "bad state!");
     mJSClass.base.flags = WRAPPER_SLOTS |
                           JSCLASS_PRIVATE_IS_NSISUPPORTS |
                           JSCLASS_NEW_RESOLVE;
     if (mFlags.IsGlobalObject())
         mJSClass.base.flags |= XPCONNECT_GLOBAL_FLAGS;
     JSPropertyOp addProperty;
     if (mFlags.WantAddProperty())
         addProperty = XPC_WN_Helper_AddProperty;
     else if (mFlags.UseJSStubForAddProperty())
         addProperty = JS_PropertyStub;
     else if (mFlags.AllowPropModsDuringResolve())
         addProperty = XPC_WN_MaybeResolvingPropertyStub;
     else
         addProperty = XPC_WN_CannotModifyPropertyStub;
     mJSClass.base.addProperty = addProperty;
     JSDeletePropertyOp delProperty;
     if (mFlags.WantDelProperty())
         delProperty = XPC_WN_Helper_DelProperty;
     else if (mFlags.UseJSStubForDelProperty())
         delProperty = JS_DeletePropertyStub;
     else if (mFlags.AllowPropModsDuringResolve())
         delProperty = XPC_WN_MaybeResolvingDeletePropertyStub;
     else
         delProperty = XPC_WN_CantDeletePropertyStub;
     mJSClass.base.delProperty = delProperty;
     if (mFlags.WantGetProperty())
         mJSClass.base.getProperty = XPC_WN_Helper_GetProperty;
     else
         mJSClass.base.getProperty = JS_PropertyStub;
     JSStrictPropertyOp setProperty;
     if (mFlags.WantSetProperty())
         setProperty = XPC_WN_Helper_SetProperty;
     else if (mFlags.UseJSStubForSetProperty())
         setProperty = JS_StrictPropertyStub;
     else if (mFlags.AllowPropModsDuringResolve())
         setProperty = XPC_WN_MaybeResolvingStrictPropertyStub;
     else
         setProperty = XPC_WN_CannotModifyStrictPropertyStub;
     mJSClass.base.setProperty = setProperty;
     // We figure out most of the enumerate strategy at call time.
     if (mFlags.WantNewEnumerate() || mFlags.WantEnumerate() ||
         mFlags.DontEnumStaticProps())
         mJSClass.base.enumerate = JS_EnumerateStub;
     else
         mJSClass.base.enumerate = XPC_WN_Shared_Enumerate;
     // We have to figure out resolve strategy at call time
     mJSClass.base.resolve = (JSResolveOp) XPC_WN_Helper_NewResolve;
     // We need to respect content-defined toString() hooks on Window objects.
     // In particular, js::DefaultValue checks for a convert stub, and the one
     // we would install below ignores anything implemented in JS.
     //
     // We've always had this behavior for most XPCWrappedNative-implemented
     // objects. However, Window was special, because the outer-window proxy
     // had a null convert hook, which means that we'd end up with the default
     // JS-engine behavior (which respects toString() overrides). We've fixed
     // the convert hook on the outer-window proxy to invoke the defaultValue
     // hook on the proxy, which in this case invokes js::DefaultValue on the
     // target. So now we need to special-case this for Window to maintain
     // consistent behavior. This can go away once Window is on WebIDL bindings.
     //
     // Note that WantOuterObject() is true if and only if this is a Window object.
     if (mFlags.WantConvert())
         mJSClass.base.convert = XPC_WN_Helper_Convert;
     else if (mFlags.WantOuterObject())
         mJSClass.base.convert = JS_ConvertStub;
     else
         mJSClass.base.convert = XPC_WN_Shared_Convert;
     if (mFlags.WantFinalize())
         mJSClass.base.finalize = XPC_WN_Helper_Finalize;
     else
         mJSClass.base.finalize = XPC_WN_NoHelper_Finalize;
     js::ObjectOps *ops = &mJSClass.base.ops;
     ops->enumerate = XPC_WN_JSOp_Enumerate;
     ops->thisObject = XPC_WN_JSOp_ThisObject;
     if (mFlags.WantCall())
         mJSClass.base.call = XPC_WN_Helper_Call;
     if (mFlags.WantConstruct())
         mJSClass.base.construct = XPC_WN_Helper_Construct;
     if (mFlags.WantHasInstance())
         mJSClass.base.hasInstance = XPC_WN_Helper_HasInstance;
     if (mFlags.IsGlobalObject())
         mJSClass.base.trace = JS_GlobalObjectTraceHook;
     else
         mJSClass.base.trace = XPCWrappedNative::Trace;
     if (mFlags.WantOuterObject())
         mJSClass.base.ext.outerObject = XPC_WN_OuterObject;
     mJSClass.base.ext.isWrappedNative = true;
 }
 /***************************************************************************/
 /***************************************************************************/
 // Compatibility hack.
 //
 // XPConnect used to do all sorts of funny tricks to find the "correct"
 // |this| object for a given method (often to the detriment of proper
 // call/apply). When these tricks were removed, a fair amount of chrome
 // code broke, because it was relying on being able to grab methods off
 // some XPCOM object (like the nsITelemetry service) and invoke them without
 // a proper |this|. So, if it's quite clear that we're in this situation and
 // about to use a |this| argument that just won't work, fix things up.
 //
 // This hack is only useful for getters/setters if someone sets an XPCOM object
 // as the prototype for a vanilla JS object and expects the XPCOM attributes to
 // work on the derived object, which we really don't want to support. But we
 // handle it anyway, for now, to minimize regression risk on an already-risky
 // landing.
 //
 // This hack is mainly useful for the NoHelper JSClass. We also fix up
 // Components.utils because it implements nsIXPCScriptable (giving it a custom
 // JSClass) but not nsIClassInfo (which would put the methods on a prototype).
 #define IS_NOHELPER_CLASS(clasp) (clasp == &XPC_WN_NoHelper_JSClass.base)
 #define IS_CU_CLASS(clasp) (clasp->name[0] == 'n' && !strcmp(clasp->name, "nsXPCComponents_Utils"))
 MOZ_ALWAYS_INLINE JSObject*
 FixUpThisIfBroken(JSObject *obj, JSObject *funobj)
 {
     if (funobj) {
         const js::Class *parentClass = js::GetObjectClass(js::GetObjectParent(funobj));
         if (MOZ_UNLIKELY((IS_NOHELPER_CLASS(parentClass) || IS_CU_CLASS(parentClass)) &&
                          (js::GetObjectClass(obj) != parentClass)))
         {
             return js::GetObjectParent(funobj);
         }
     }
     return obj;
 }
 bool
 XPC_WN_CallMethod(JSContext *cx, unsigned argc, jsval *vp)
 {
     JS::CallArgs args = JS::CallArgsFromVp(argc, vp);
     MOZ_ASSERT(JS_TypeOfValue(cx, args.calleev()) == JSTYPE_FUNCTION, "bad function");
     RootedObject funobj(cx, &args.callee());
     RootedObject obj(cx, JS_THIS_OBJECT(cx, vp));
     if (!obj)
         return false;
     obj = FixUpThisIfBroken(obj, funobj);
     XPCCallContext ccx(JS_CALLER, cx, obj, funobj, JSID_VOIDHANDLE, args.length(),
                        args.array(), vp);
     XPCWrappedNative* wrapper = ccx.GetWrapper();
     THROW_AND_RETURN_IF_BAD_WRAPPER(cx, wrapper);
     XPCNativeInterface* iface;
     XPCNativeMember*    member;
     if (!XPCNativeMember::GetCallInfo(funobj, &iface, &member))
         return Throw(NS_ERROR_XPC_CANT_GET_METHOD_INFO, cx);
     ccx.SetCallInfo(iface, member, false);
     return XPCWrappedNative::CallMethod(ccx);
 }
 bool
 XPC_WN_GetterSetter(JSContext *cx, unsigned argc, jsval *vp)
 {
     JS::CallArgs args = JS::CallArgsFromVp(argc, vp);
     MOZ_ASSERT(JS_TypeOfValue(cx, args.calleev()) == JSTYPE_FUNCTION, "bad function");
     RootedObject funobj(cx, &args.callee());
     RootedObject obj(cx, JS_THIS_OBJECT(cx, vp));
     if (!obj)
         return false;
     obj = FixUpThisIfBroken(obj, funobj);
     XPCCallContext ccx(JS_CALLER, cx, obj, funobj, JSID_VOIDHANDLE, args.length(),
                        args.array(), vp);
     XPCWrappedNative* wrapper = ccx.GetWrapper();
     THROW_AND_RETURN_IF_BAD_WRAPPER(cx, wrapper);
     XPCNativeInterface* iface;
     XPCNativeMember*    member;
     if (!XPCNativeMember::GetCallInfo(funobj, &iface, &member))
         return Throw(NS_ERROR_XPC_CANT_GET_METHOD_INFO, cx);
     if (args.length() != 0 && member->IsWritableAttribute()) {
         ccx.SetCallInfo(iface, member, true);
         bool retval = XPCWrappedNative::SetAttribute(ccx);
         if (retval)
             args.rval().set(args[0]);
         return retval;
     }
     // else...
     ccx.SetCallInfo(iface, member, false);
     return XPCWrappedNative::GetAttribute(ccx);
 }
 /***************************************************************************/
 static bool
 XPC_WN_Shared_Proto_Enumerate(JSContext *cx, HandleObject obj)
 {
     MOZ_ASSERT(js::GetObjectClass(obj) == &XPC_WN_ModsAllowed_WithCall_Proto_JSClass ||
                js::GetObjectClass(obj) == &XPC_WN_ModsAllowed_NoCall_Proto_JSClass ||
                js::GetObjectClass(obj) == &XPC_WN_NoMods_WithCall_Proto_JSClass ||
                js::GetObjectClass(obj) == &XPC_WN_NoMods_NoCall_Proto_JSClass,
                "bad proto");
     XPCWrappedNativeProto* self =
         (XPCWrappedNativeProto*) xpc_GetJSPrivate(obj);
     if (!self)
         return false;
     if (self->GetScriptableInfo() &&
         self->GetScriptableInfo()->GetFlags().DontEnumStaticProps())
         return true;
     XPCNativeSet* set = self->GetSet();
     if (!set)
         return false;
     XPCCallContext ccx(JS_CALLER, cx);
     if (!ccx.IsValid())
         return false;
     uint16_t interface_count = set->GetInterfaceCount();
     XPCNativeInterface** interfaceArray = set->GetInterfaceArray();
     for (uint16_t i = 0; i < interface_count; i++) {
         XPCNativeInterface* iface = interfaceArray[i];
         uint16_t member_count = iface->GetMemberCount();
         for (uint16_t k = 0; k < member_count; k++) {
             if (!xpc_ForcePropertyResolve(cx, obj, iface->GetMemberAt(k)->GetName()))
                 return false;
         }
     }
     return true;
 }
 static void
 XPC_WN_Shared_Proto_Finalize(js::FreeOp *fop, JSObject *obj)
 {
     // This can be null if xpc shutdown has already happened
     XPCWrappedNativeProto* p = (XPCWrappedNativeProto*) xpc_GetJSPrivate(obj);
     if (p)
         p->JSProtoObjectFinalized(fop, obj);
 }
 static void
 XPC_WN_Shared_Proto_Trace(JSTracer *trc, JSObject *obj)
 {
     // This can be null if xpc shutdown has already happened
     XPCWrappedNativeProto* p =
         (XPCWrappedNativeProto*) xpc_GetJSPrivate(obj);
     if (p)
         p->TraceInside(trc);
 }
 /*****************************************************/
 static bool
 XPC_WN_ModsAllowed_Proto_Resolve(JSContext *cx, HandleObject obj, HandleId id)
 {
     MOZ_ASSERT(js::GetObjectClass(obj) == &XPC_WN_ModsAllowed_WithCall_Proto_JSClass ||
                js::GetObjectClass(obj) == &XPC_WN_ModsAllowed_NoCall_Proto_JSClass,
                "bad proto");
     XPCWrappedNativeProto* self =
         (XPCWrappedNativeProto*) xpc_GetJSPrivate(obj);
     if (!self)
         return false;
     XPCCallContext ccx(JS_CALLER, cx);
     if (!ccx.IsValid())
         return false;
     XPCNativeScriptableInfo* si = self->GetScriptableInfo();
     unsigned enumFlag = (si && si->GetFlags().DontEnumStaticProps()) ?
 : JSPROP_ENUMERATE;
     return DefinePropertyIfFound(ccx, obj, id,
                                  self->GetSet(), nullptr, nullptr,
                                  self->GetScope(),
                                  true, nullptr, nullptr, si,
                                  enumFlag, nullptr);
 }
 const js::Class XPC_WN_ModsAllowed_WithCall_Proto_JSClass = {
     "XPC_WN_ModsAllowed_WithCall_Proto_JSClass", // name;
     WRAPPER_SLOTS, // flags;
     /* Mandatory non-null function pointer members. */
     JS_PropertyStub,                // addProperty;
     JS_DeletePropertyStub,          // delProperty;
     JS_PropertyStub,                // getProperty;
     JS_StrictPropertyStub,          // setProperty;
     XPC_WN_Shared_Proto_Enumerate,  // enumerate;
     XPC_WN_ModsAllowed_Proto_Resolve, // resolve;
     JS_ConvertStub,                 // convert;
     XPC_WN_Shared_Proto_Finalize,   // finalize;
     /* Optionally non-null members start here. */
     nullptr,                         // call;
     nullptr,                         // construct;
     nullptr,                         // hasInstance;
     XPC_WN_Shared_Proto_Trace,      // trace;
     JS_NULL_CLASS_SPEC,
     JS_NULL_CLASS_EXT,
     XPC_WN_WithCall_ObjectOps
 };
 const js::Class XPC_WN_ModsAllowed_NoCall_Proto_JSClass = {
     "XPC_WN_ModsAllowed_NoCall_Proto_JSClass", // name;
     WRAPPER_SLOTS,                  // flags;
     /* Mandatory non-null function pointer members. */
     JS_PropertyStub,                // addProperty;
     JS_DeletePropertyStub,          // delProperty;
     JS_PropertyStub,                // getProperty;
     JS_StrictPropertyStub,          // setProperty;
     XPC_WN_Shared_Proto_Enumerate,  // enumerate;
     XPC_WN_ModsAllowed_Proto_Resolve, // resolve;
     JS_ConvertStub,                 // convert;
     XPC_WN_Shared_Proto_Finalize,   // finalize;
     /* Optionally non-null members start here. */
     nullptr,                         // call;
     nullptr,                         // construct;
     nullptr,                         // hasInstance;
     XPC_WN_Shared_Proto_Trace,      // trace;
     JS_NULL_CLASS_SPEC,
     JS_NULL_CLASS_EXT,
     XPC_WN_NoCall_ObjectOps
 };
 /***************************************************************************/
 static bool
 XPC_WN_OnlyIWrite_Proto_AddPropertyStub(JSContext *cx, HandleObject obj, HandleId id,
                                         MutableHandleValue vp)
 {
     MOZ_ASSERT(js::GetObjectClass(obj) == &XPC_WN_NoMods_WithCall_Proto_JSClass ||
                js::GetObjectClass(obj) == &XPC_WN_NoMods_NoCall_Proto_JSClass,
                "bad proto");
     XPCWrappedNativeProto* self =
         (XPCWrappedNativeProto*) xpc_GetJSPrivate(obj);
     if (!self)
         return false;
     XPCCallContext ccx(JS_CALLER, cx);
     if (!ccx.IsValid())
         return false;
     // Allow XPConnect to add the property only
     if (ccx.GetResolveName() == id)
         return true;
     return Throw(NS_ERROR_XPC_BAD_OP_ON_WN_PROTO, cx);
 }
 static bool
 XPC_WN_OnlyIWrite_Proto_SetPropertyStub(JSContext *cx, HandleObject obj, HandleId id, bool strict,
                                         MutableHandleValue vp)
 {
     return XPC_WN_OnlyIWrite_Proto_AddPropertyStub(cx, obj, id, vp);
 }
 static bool
 XPC_WN_NoMods_Proto_Resolve(JSContext *cx, HandleObject obj, HandleId id)
 {
     MOZ_ASSERT(js::GetObjectClass(obj) == &XPC_WN_NoMods_WithCall_Proto_JSClass ||
                js::GetObjectClass(obj) == &XPC_WN_NoMods_NoCall_Proto_JSClass,
                "bad proto");
     XPCWrappedNativeProto* self =
         (XPCWrappedNativeProto*) xpc_GetJSPrivate(obj);
     if (!self)
         return false;
     XPCCallContext ccx(JS_CALLER, cx);
     if (!ccx.IsValid())
         return false;
     XPCNativeScriptableInfo* si = self->GetScriptableInfo();
     unsigned enumFlag = (si && si->GetFlags().DontEnumStaticProps()) ?
 : JSPROP_ENUMERATE;
     return DefinePropertyIfFound(ccx, obj, id,
                                  self->GetSet(), nullptr, nullptr,
                                  self->GetScope(),
                                  true, nullptr, nullptr, si,
                                  JSPROP_READONLY |
                                  JSPROP_PERMANENT |
                                  enumFlag, nullptr);
 }
 const js::Class XPC_WN_NoMods_WithCall_Proto_JSClass = {
     "XPC_WN_NoMods_WithCall_Proto_JSClass",    // name;
     WRAPPER_SLOTS,                             // flags;
     /* Mandatory non-null function pointer members. */
     XPC_WN_OnlyIWrite_Proto_AddPropertyStub,   // addProperty;
     XPC_WN_CantDeletePropertyStub,             // delProperty;
     JS_PropertyStub,                           // getProperty;
     XPC_WN_OnlyIWrite_Proto_SetPropertyStub,   // setProperty;
     XPC_WN_Shared_Proto_Enumerate,             // enumerate;
     XPC_WN_NoMods_Proto_Resolve,               // resolve;
     JS_ConvertStub,                            // convert;
     XPC_WN_Shared_Proto_Finalize,              // finalize;
     /* Optionally non-null members start here. */
     nullptr,                         // call;
     nullptr,                         // construct;
     nullptr,                         // hasInstance;
     XPC_WN_Shared_Proto_Trace,      // trace;
     JS_NULL_CLASS_SPEC,
     JS_NULL_CLASS_EXT,
     XPC_WN_WithCall_ObjectOps
 };
 const js::Class XPC_WN_NoMods_NoCall_Proto_JSClass = {
     "XPC_WN_NoMods_NoCall_Proto_JSClass",      // name;
     WRAPPER_SLOTS,                             // flags;
     /* Mandatory non-null function pointer members. */
     XPC_WN_OnlyIWrite_Proto_AddPropertyStub,   // addProperty;
     XPC_WN_CantDeletePropertyStub,             // delProperty;
     JS_PropertyStub,                           // getProperty;
     XPC_WN_OnlyIWrite_Proto_SetPropertyStub,   // setProperty;
     XPC_WN_Shared_Proto_Enumerate,             // enumerate;
     XPC_WN_NoMods_Proto_Resolve,               // resolve;
     JS_ConvertStub,                            // convert;
     XPC_WN_Shared_Proto_Finalize,              // finalize;
     /* Optionally non-null members start here. */
     nullptr,                         // call;
     nullptr,                         // construct;
     nullptr,                         // hasInstance;
     XPC_WN_Shared_Proto_Trace,      // trace;
     JS_NULL_CLASS_SPEC,
     JS_NULL_CLASS_EXT,
     XPC_WN_NoCall_ObjectOps
 };
 /***************************************************************************/
 static bool
 XPC_WN_TearOff_Enumerate(JSContext *cx, HandleObject obj)
 {
     XPCCallContext ccx(JS_CALLER, cx, obj);
     XPCWrappedNative* wrapper = ccx.GetWrapper();
     THROW_AND_RETURN_IF_BAD_WRAPPER(cx, wrapper);
     XPCWrappedNativeTearOff* to = ccx.GetTearOff();
     XPCNativeInterface* iface;
     if (!to || nullptr == (iface = to->GetInterface()))
         return Throw(NS_ERROR_XPC_BAD_OP_ON_WN_PROTO, cx);
     uint16_t member_count = iface->GetMemberCount();
     for (uint16_t k = 0; k < member_count; k++) {
         if (!xpc_ForcePropertyResolve(cx, obj, iface->GetMemberAt(k)->GetName()))
             return false;
     }
     return true;
 }
 static bool
 XPC_WN_TearOff_Resolve(JSContext *cx, HandleObject obj, HandleId id)
 {
     XPCCallContext ccx(JS_CALLER, cx, obj);
     XPCWrappedNative* wrapper = ccx.GetWrapper();
     THROW_AND_RETURN_IF_BAD_WRAPPER(cx, wrapper);
     XPCWrappedNativeTearOff* to = ccx.GetTearOff();
     XPCNativeInterface* iface;
     if (!to || nullptr == (iface = to->GetInterface()))
         return Throw(NS_ERROR_XPC_BAD_OP_ON_WN_PROTO, cx);
     return DefinePropertyIfFound(ccx, obj, id, nullptr, iface, nullptr,
                                  wrapper->GetScope(),
                                  true, nullptr, nullptr, nullptr,
                                  JSPROP_READONLY |
                                  JSPROP_PERMANENT |
                                  JSPROP_ENUMERATE, nullptr);
 }
 static void
 XPC_WN_TearOff_Finalize(js::FreeOp *fop, JSObject *obj)
 {
     XPCWrappedNativeTearOff* p = (XPCWrappedNativeTearOff*)
         xpc_GetJSPrivate(obj);
     if (!p)
         return;
     p->JSObjectFinalized();
 }
 const js::Class XPC_WN_Tearoff_JSClass = {
     "WrappedNative_TearOff",                   // name;
     WRAPPER_SLOTS,                             // flags;
     XPC_WN_OnlyIWrite_AddPropertyStub,         // addProperty;
     XPC_WN_CantDeletePropertyStub,             // delProperty;
     JS_PropertyStub,                           // getProperty;
     XPC_WN_OnlyIWrite_SetPropertyStub,         // setProperty;
     XPC_WN_TearOff_Enumerate,                  // enumerate;
     XPC_WN_TearOff_Resolve,                    // resolve;
     XPC_WN_Shared_Convert,                     // convert;
     XPC_WN_TearOff_Finalize                    // finalize;
 };

The Tor Browser / annotate

js/xpconnect/src/XPCWrappedNativeJSOps.cpp@b8a032363ba2 (annotated)

js/xpconnect/src/XPCWrappedNativeJSOps.cpp