Bug 1019191 part 23. Eliminate the ppArgRef argument of xpc_qsUnwrapArgImpl and UnwrapArg, since we're now always handing out a ref in ppArg. r=peterv

dom/bindings/BindingUtils.cpp

@@ -827,10 +827,8 @@ QueryInterface(JSContext* cx, unsigned argc, JS::Value* vp)
 
   // Switch this to UnwrapDOMObjectToISupports once our global objects are
   // using new bindings.
-  nsISupports* native = nullptr;
-  nsCOMPtr<nsISupports> nativeRef;
-  UnwrapArg<nsISupports>(cx, obj, &native,
-                         static_cast<nsISupports**>(getter_AddRefs(nativeRef)));
+  nsCOMPtr<nsISupports> native;
+  UnwrapArg<nsISupports>(cx, obj, getter_AddRefs(native));
   if (!native) {
     return Throw(cx, NS_ERROR_FAILURE);
   }
@@ -843,10 +841,9 @@ QueryInterface(JSContext* cx, unsigned argc, JS::Value* vp)
     return Throw(cx, NS_ERROR_XPC_BAD_CONVERT_JS);
   }
 
-  nsIJSID* iid;
-  SelfRef iidRef;
+  nsCOMPtr<nsIJSID> iid;
   obj = &args[0].toObject();
-  if (NS_FAILED(UnwrapArg<nsIJSID>(cx, obj, &iid, &iidRef.ptr))) {
+  if (NS_FAILED(UnwrapArg<nsIJSID>(cx, obj, getter_AddRefs(iid)))) {
     return Throw(cx, NS_ERROR_XPC_BAD_CONVERT_JS);
   }
   MOZ_ASSERT(iid);

dom/bindings/BindingUtils.h

@@ -40,8 +40,8 @@ class nsIJSID;
 class nsPIDOMWindow;
 
 extern nsresult
-xpc_qsUnwrapArgImpl(JSContext* cx, JS::Handle<JSObject*> src, const nsIID& iid, void** ppArg,
-                    nsISupports** ppArgRef);
+xpc_qsUnwrapArgImpl(JSContext* cx, JS::Handle<JSObject*> src, const nsIID& iid,
+                    void** ppArg);
 
 namespace mozilla {
 namespace dom {
@@ -57,16 +57,12 @@ struct SelfRef
 };
 
 /** Convert a jsval to an XPCOM pointer. */
-template <class Interface, class StrongRefType>
+template <class Interface>
 inline nsresult
-UnwrapArg(JSContext* cx, JS::Handle<JSObject*> src, Interface** ppArg,
-          StrongRefType** ppArgRef)
+UnwrapArg(JSContext* cx, JS::Handle<JSObject*> src, Interface** ppArg)
 {
-  nsISupports* argRef = *ppArgRef;
-  nsresult rv = xpc_qsUnwrapArgImpl(cx, src, NS_GET_TEMPLATE_IID(Interface),
-                                    reinterpret_cast<void**>(ppArg), &argRef);
-  *ppArgRef = static_cast<StrongRefType*>(argRef);
-  return rv;
+  return xpc_qsUnwrapArgImpl(cx, src, NS_GET_TEMPLATE_IID(Interface),
+                             reinterpret_cast<void**>(ppArg));
 }
 
 inline const ErrNum

dom/bindings/Codegen.py

@@ -3677,7 +3677,7 @@ class CastableObjectUnwrapper():
                   // want to be in that compartment for the UnwrapArg call.
                   JS::Rooted<JSObject*> source(cx, ${source});
                   JSAutoCompartment ac(cx, ${source});
-                  rv = UnwrapArg<${type}>(cx, source, &objPtr, &objRef.ptr);
+                  rv = UnwrapArg<${type}>(cx, source, getter_AddRefs(objPtr));
                 }
                 """)
         else:
@@ -3685,19 +3685,16 @@ class CastableObjectUnwrapper():
             self.substitution["source"] = source
             xpconnectUnwrap = (
                 "JS::Rooted<JSObject*> source(cx, ${source});\n"
-                "nsresult rv = UnwrapArg<${type}>(cx, source, &objPtr, &objRef.ptr);\n")
+                "nsresult rv = UnwrapArg<${type}>(cx, source, getter_AddRefs(objPtr));\n")
 
         if descriptor.hasXPConnectImpls:
             self.substitution["codeOnFailure"] = string.Template(
-                "${type} *objPtr;\n"
-                "SelfRef objRef;\n" +
+                "nsRefPtr<${type}> objPtr;\n" +
                 xpconnectUnwrap +
                 "if (NS_FAILED(rv)) {\n"
                 "${indentedCodeOnFailure}"
                 "}\n"
-                "// We should be castable!\n"
-                "MOZ_ASSERT(!objRef.ptr);\n"
-                "// We should have an object, too!\n"
+                "// We should have an object\n"
                 "MOZ_ASSERT(objPtr);\n"
                 "${target} = objPtr;\n"
             ).substitute(self.substitution,
@@ -4766,21 +4763,14 @@ def getJSToNativeConversionInfo(type, descriptorProvider, failureCode=None,
                 holderType = "nsRefPtr<" + typeName + ">"
             templateBody += (
                 "JS::Rooted<JSObject*> source(cx, &${val}.toObject());\n" +
-                typePtr + " tmp;\n"
-                "if (NS_FAILED(UnwrapArg<" + typeName + ">(cx, source, &tmp, static_cast<" + typeName + "**>(getter_AddRefs(${holderName}))))) {\n")
+                "if (NS_FAILED(UnwrapArg<" + typeName + ">(cx, source, getter_AddRefs(${holderName})))) {\n")
             templateBody += CGIndenter(onFailureBadType(failureCode,
                                                         descriptor.interface.identifier.name)).define()
             templateBody += ("}\n"
-                             "MOZ_ASSERT(tmp);\n")
+                             "MOZ_ASSERT(${holderName});\n")
 
-            if not isDefinitelyObject and not forceOwningType:
-                templateBody += dedent("""
-                    // UnwrapArg never sets **ppArg without also setting *ppArgRef
-                    MOZ_ASSERT(${holderName});
-                    """)
-
-            # And store our tmp, before it goes out of scope.
-            templateBody += "${declName} = tmp;\n"
+            # And store our value in ${declName}
+            templateBody += "${declName} = ${holderName};\n"
 
         # Just pass failureCode, not onFailureBadType, here, so we'll report the
         # thing as not an object as opposed to not implementing whatever our

js/xpconnect/src/XPCQuickStubs.cpp

@@ -23,31 +23,26 @@ nsresult
 xpc_qsUnwrapArgImpl(JSContext *cx,
                     HandleObject src,
                     const nsIID &iid,
-                    void **ppArg,
-                    nsISupports **ppArgRef)
+                    void **ppArg)
 {
     nsISupports *iface = xpc::UnwrapReflectorToISupports(src);
     if (iface) {
         if (NS_FAILED(iface->QueryInterface(iid, ppArg))) {
-            *ppArgRef = nullptr;
             return NS_ERROR_XPC_BAD_CONVERT_JS;
         }
 
-        *ppArgRef = static_cast<nsISupports*>(*ppArg);
         return NS_OK;
     }
 
     // Create the ccx needed for quick stubs.
     XPCCallContext ccx(JS_CALLER, cx);
     if (!ccx.IsValid()) {
-        *ppArgRef = nullptr;
         return NS_ERROR_XPC_BAD_CONVERT_JS;
     }
 
     nsRefPtr<nsXPCWrappedJS> wrappedJS;
     nsresult rv = nsXPCWrappedJS::GetNewOrUsed(src, iid, getter_AddRefs(wrappedJS));
     if (NS_FAILED(rv) || !wrappedJS) {
-        *ppArgRef = nullptr;
         return rv;
     }
 
@@ -55,11 +50,7 @@ xpc_qsUnwrapArgImpl(JSContext *cx,
     // the right thing for the various 'special' interfaces; e.g.
     // nsIPropertyBag. We must use AggregatedQueryInterface in cases where
     // there is an outer to avoid nasty recursion.
-    rv = wrappedJS->QueryInterface(iid, ppArg);
-    if (NS_SUCCEEDED(rv)) {
-        *ppArgRef = static_cast<nsISupports*>(*ppArg);
-    }
-    return rv;
+    return wrappedJS->QueryInterface(iid, ppArg);
 }
 
 namespace xpc {

js/xpconnect/src/XPCQuickStubs.h

@@ -12,7 +12,7 @@
 /* XPCQuickStubs.h - Support functions used only by Web IDL bindings, for now. */
 
 nsresult
-xpc_qsUnwrapArgImpl(JSContext *cx, JS::HandleObject src, const nsIID &iid, void **ppArg,
-                    nsISupports **ppArgRef);
+xpc_qsUnwrapArgImpl(JSContext *cx, JS::HandleObject src, const nsIID &iid,
+                    void **ppArg);
 
 #endif /* xpcquickstubs_h___ */