michael@0: /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
michael@0: /* vim: set ts=8 sts=4 et sw=4 tw=99: */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "xpcprivate.h"
michael@0: #include "XPCJSWeakReference.h"
michael@0: 
michael@0: #include "nsContentUtils.h"
michael@0: 
michael@0: using namespace JS;
michael@0: 
michael@0: xpcJSWeakReference::xpcJSWeakReference()
michael@0: {
michael@0: }
michael@0: 
michael@0: NS_IMPL_ISUPPORTS(xpcJSWeakReference, xpcIJSWeakReference)
michael@0: 
michael@0: nsresult xpcJSWeakReference::Init(JSContext* cx, const JS::Value& object)
michael@0: {
michael@0:     if (!object.isObject())
michael@0:         return NS_OK;
michael@0: 
michael@0:     JS::RootedObject obj(cx, &object.toObject());
michael@0: 
michael@0:     XPCCallContext ccx(NATIVE_CALLER, cx);
michael@0: 
michael@0:     // See if the object is a wrapped native that supports weak references.
michael@0:     nsISupports* supports =
michael@0:         nsXPConnect::XPConnect()->GetNativeOfWrapper(cx, obj);
michael@0:     nsCOMPtr<nsISupportsWeakReference> supportsWeakRef =
michael@0:         do_QueryInterface(supports);
michael@0:     if (supportsWeakRef) {
michael@0:         supportsWeakRef->GetWeakReference(getter_AddRefs(mReferent));
michael@0:         if (mReferent) {
michael@0:             return NS_OK;
michael@0:         }
michael@0:     }
michael@0:     // If it's not a wrapped native, or it is a wrapped native that does not
michael@0:     // support weak references, fall back to getting a weak ref to the object.
michael@0: 
michael@0:     // See if object is a wrapped JSObject.
michael@0:     nsRefPtr<nsXPCWrappedJS> wrapped;
michael@0:     nsresult rv = nsXPCWrappedJS::GetNewOrUsed(obj,
michael@0:                                                NS_GET_IID(nsISupports),
michael@0:                                                getter_AddRefs(wrapped));
michael@0:     if (!wrapped) {
michael@0:         NS_ERROR("can't get nsISupportsWeakReference wrapper for obj");
michael@0:         return rv;
michael@0:     }
michael@0: 
michael@0:     return wrapped->GetWeakReference(getter_AddRefs(mReferent));
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: xpcJSWeakReference::Get(JSContext* aCx, MutableHandleValue aRetval)
michael@0: {
michael@0:     aRetval.setNull();
michael@0: 
michael@0:     if (!mReferent) {
michael@0:         return NS_OK;
michael@0:     }
michael@0: 
michael@0:     nsCOMPtr<nsISupports> supports = do_QueryReferent(mReferent);
michael@0:     if (!supports) {
michael@0:         return NS_OK;
michael@0:     }
michael@0: 
michael@0:     nsCOMPtr<nsIXPConnectWrappedJS> wrappedObj = do_QueryInterface(supports);
michael@0:     if (!wrappedObj) {
michael@0:         // We have a generic XPCOM object that supports weak references here.
michael@0:         // Wrap it and pass it out.
michael@0:         return nsContentUtils::WrapNative(aCx, supports,
michael@0:                                           &NS_GET_IID(nsISupports),
michael@0:                                           aRetval);
michael@0:     }
michael@0: 
michael@0:     JS::RootedObject obj(aCx, wrappedObj->GetJSObject());
michael@0:     if (!obj) {
michael@0:         return NS_OK;
michael@0:     }
michael@0: 
michael@0:     // Most users of XPCWrappedJS don't need to worry about
michael@0:     // re-wrapping because things are implicitly rewrapped by
michael@0:     // xpcconvert. However, because we're doing this directly
michael@0:     // through the native call context, we need to call
michael@0:     // JS_WrapObject().
michael@0:     if (!JS_WrapObject(aCx, &obj)) {
michael@0:         return NS_ERROR_FAILURE;
michael@0:     }
michael@0: 
michael@0:     aRetval.setObject(*obj);
michael@0:     return NS_OK;
michael@0: }